1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Elists; use Elists;
32 with Einfo; use Einfo;
33 with Errout; use Errout;
34 with Eval_Fat; use Eval_Fat;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Dist; use Exp_Dist;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Itypes; use Itypes;
44 with Layout; use Layout;
46 with Lib.Xref; use Lib.Xref;
47 with Namet; use Namet;
48 with Nmake; use Nmake;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Case; use Sem_Case;
56 with Sem_Cat; use Sem_Cat;
57 with Sem_Ch6; use Sem_Ch6;
58 with Sem_Ch7; use Sem_Ch7;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch13; use Sem_Ch13;
61 with Sem_Dim; use Sem_Dim;
62 with Sem_Disp; use Sem_Disp;
63 with Sem_Dist; use Sem_Dist;
64 with Sem_Elim; use Sem_Elim;
65 with Sem_Eval; use Sem_Eval;
66 with Sem_Mech; use Sem_Mech;
67 with Sem_Res; use Sem_Res;
68 with Sem_Smem; use Sem_Smem;
69 with Sem_Type; use Sem_Type;
70 with Sem_Util; use Sem_Util;
71 with Sem_Warn; use Sem_Warn;
72 with Stand; use Stand;
73 with Sinfo; use Sinfo;
74 with Sinput; use Sinput;
75 with Snames; use Snames;
76 with Targparm; use Targparm;
77 with Tbuild; use Tbuild;
78 with Ttypes; use Ttypes;
79 with Uintp; use Uintp;
80 with Urealp; use Urealp;
82 package body Sem_Ch3 is
84 -----------------------
85 -- Local Subprograms --
86 -----------------------
88 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
89 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
90 -- abstract interface types implemented by a record type or a derived
93 procedure Build_Derived_Type
95 Parent_Type : Entity_Id;
96 Derived_Type : Entity_Id;
97 Is_Completion : Boolean;
98 Derive_Subps : Boolean := True);
99 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
100 -- the N_Full_Type_Declaration node containing the derived type definition.
101 -- Parent_Type is the entity for the parent type in the derived type
102 -- definition and Derived_Type the actual derived type. Is_Completion must
103 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
104 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
105 -- completion of a private type declaration. If Is_Completion is set to
106 -- True, N is the completion of a private type declaration and Derived_Type
107 -- is different from the defining identifier inside N (i.e. Derived_Type /=
108 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
109 -- subprograms should be derived. The only case where this parameter is
110 -- False is when Build_Derived_Type is recursively called to process an
111 -- implicit derived full type for a type derived from a private type (in
112 -- that case the subprograms must only be derived for the private view of
115 -- ??? These flags need a bit of re-examination and re-documentation:
116 -- ??? are they both necessary (both seem related to the recursion)?
118 procedure Build_Derived_Access_Type
120 Parent_Type : Entity_Id;
121 Derived_Type : Entity_Id);
122 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
123 -- create an implicit base if the parent type is constrained or if the
124 -- subtype indication has a constraint.
126 procedure Build_Derived_Array_Type
128 Parent_Type : Entity_Id;
129 Derived_Type : Entity_Id);
130 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
131 -- create an implicit base if the parent type is constrained or if the
132 -- subtype indication has a constraint.
134 procedure Build_Derived_Concurrent_Type
136 Parent_Type : Entity_Id;
137 Derived_Type : Entity_Id);
138 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
139 -- protected type, inherit entries and protected subprograms, check
140 -- legality of discriminant constraints if any.
142 procedure Build_Derived_Enumeration_Type
144 Parent_Type : Entity_Id;
145 Derived_Type : Entity_Id);
146 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
147 -- type, we must create a new list of literals. Types derived from
148 -- Character and [Wide_]Wide_Character are special-cased.
150 procedure Build_Derived_Numeric_Type
152 Parent_Type : Entity_Id;
153 Derived_Type : Entity_Id);
154 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
155 -- an anonymous base type, and propagate constraint to subtype if needed.
157 procedure Build_Derived_Private_Type
159 Parent_Type : Entity_Id;
160 Derived_Type : Entity_Id;
161 Is_Completion : Boolean;
162 Derive_Subps : Boolean := True);
163 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
164 -- because the parent may or may not have a completion, and the derivation
165 -- may itself be a completion.
167 procedure Build_Derived_Record_Type
169 Parent_Type : Entity_Id;
170 Derived_Type : Entity_Id;
171 Derive_Subps : Boolean := True);
172 -- Subsidiary procedure used for tagged and untagged record types
173 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
174 -- All parameters are as in Build_Derived_Type except that N, in
175 -- addition to being an N_Full_Type_Declaration node, can also be an
176 -- N_Private_Extension_Declaration node. See the definition of this routine
177 -- for much more info. Derive_Subps indicates whether subprograms should be
178 -- derived from the parent type. The only case where Derive_Subps is False
179 -- is for an implicit derived full type for a type derived from a private
180 -- type (see Build_Derived_Type).
182 procedure Build_Discriminal (Discrim : Entity_Id);
183 -- Create the discriminal corresponding to discriminant Discrim, that is
184 -- the parameter corresponding to Discrim to be used in initialization
185 -- procedures for the type where Discrim is a discriminant. Discriminals
186 -- are not used during semantic analysis, and are not fully defined
187 -- entities until expansion. Thus they are not given a scope until
188 -- initialization procedures are built.
190 function Build_Discriminant_Constraints
193 Derived_Def : Boolean := False) return Elist_Id;
194 -- Validate discriminant constraints and return the list of the constraints
195 -- in order of discriminant declarations, where T is the discriminated
196 -- unconstrained type. Def is the N_Subtype_Indication node where the
197 -- discriminants constraints for T are specified. Derived_Def is True
198 -- when building the discriminant constraints in a derived type definition
199 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
200 -- type and Def is the constraint "(xxx)" on T and this routine sets the
201 -- Corresponding_Discriminant field of the discriminants in the derived
202 -- type D to point to the corresponding discriminants in the parent type T.
204 procedure Build_Discriminated_Subtype
208 Related_Nod : Node_Id;
209 For_Access : Boolean := False);
210 -- Subsidiary procedure to Constrain_Discriminated_Type and to
211 -- Process_Incomplete_Dependents. Given
213 -- T (a possibly discriminated base type)
214 -- Def_Id (a very partially built subtype for T),
216 -- the call completes Def_Id to be the appropriate E_*_Subtype.
218 -- The Elist is the list of discriminant constraints if any (it is set
219 -- to No_Elist if T is not a discriminated type, and to an empty list if
220 -- T has discriminants but there are no discriminant constraints). The
221 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
222 -- The For_Access says whether or not this subtype is really constraining
223 -- an access type. That is its sole purpose is the designated type of an
224 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
225 -- is built to avoid freezing T when the access subtype is frozen.
227 function Build_Scalar_Bound
230 Der_T : Entity_Id) return Node_Id;
231 -- The bounds of a derived scalar type are conversions of the bounds of
232 -- the parent type. Optimize the representation if the bounds are literals.
233 -- Needs a more complete spec--what are the parameters exactly, and what
234 -- exactly is the returned value, and how is Bound affected???
236 procedure Build_Underlying_Full_View
240 -- If the completion of a private type is itself derived from a private
241 -- type, or if the full view of a private subtype is itself private, the
242 -- back-end has no way to compute the actual size of this type. We build
243 -- an internal subtype declaration of the proper parent type to convey
244 -- this information. This extra mechanism is needed because a full
245 -- view cannot itself have a full view (it would get clobbered during
248 procedure Check_Access_Discriminant_Requires_Limited
251 -- Check the restriction that the type to which an access discriminant
252 -- belongs must be a concurrent type or a descendant of a type with
253 -- the reserved word 'limited' in its declaration.
255 procedure Check_Anonymous_Access_Components
259 Comp_List : Node_Id);
260 -- Ada 2005 AI-382: an access component in a record definition can refer to
261 -- the enclosing record, in which case it denotes the type itself, and not
262 -- the current instance of the type. We create an anonymous access type for
263 -- the component, and flag it as an access to a component, so accessibility
264 -- checks are properly performed on it. The declaration of the access type
265 -- is placed ahead of that of the record to prevent order-of-elaboration
266 -- circularity issues in Gigi. We create an incomplete type for the record
267 -- declaration, which is the designated type of the anonymous access.
269 procedure Check_Delta_Expression (E : Node_Id);
270 -- Check that the expression represented by E is suitable for use as a
271 -- delta expression, i.e. it is of real type and is static.
273 procedure Check_Digits_Expression (E : Node_Id);
274 -- Check that the expression represented by E is suitable for use as a
275 -- digits expression, i.e. it is of integer type, positive and static.
277 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
278 -- Validate the initialization of an object declaration. T is the required
279 -- type, and Exp is the initialization expression.
281 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
282 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
284 procedure Check_Or_Process_Discriminants
287 Prev : Entity_Id := Empty);
288 -- If N is the full declaration of the completion T of an incomplete or
289 -- private type, check its discriminants (which are already known to be
290 -- conformant with those of the partial view, see Find_Type_Name),
291 -- otherwise process them. Prev is the entity of the partial declaration,
294 procedure Check_Real_Bound (Bound : Node_Id);
295 -- Check given bound for being of real type and static. If not, post an
296 -- appropriate message, and rewrite the bound with the real literal zero.
298 procedure Constant_Redeclaration
302 -- Various checks on legality of full declaration of deferred constant.
303 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
304 -- node. The caller has not yet set any attributes of this entity.
306 function Contain_Interface
308 Ifaces : Elist_Id) return Boolean;
309 -- Ada 2005: Determine whether Iface is present in the list Ifaces
311 procedure Convert_Scalar_Bounds
313 Parent_Type : Entity_Id;
314 Derived_Type : Entity_Id;
316 -- For derived scalar types, convert the bounds in the type definition to
317 -- the derived type, and complete their analysis. Given a constraint of the
318 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
319 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
320 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
321 -- subtype are conversions of those bounds to the derived_type, so that
322 -- their typing is consistent.
324 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
325 -- Copies attributes from array base type T2 to array base type T1. Copies
326 -- only attributes that apply to base types, but not subtypes.
328 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
329 -- Copies attributes from array subtype T2 to array subtype T1. Copies
330 -- attributes that apply to both subtypes and base types.
332 procedure Create_Constrained_Components
336 Constraints : Elist_Id);
337 -- Build the list of entities for a constrained discriminated record
338 -- subtype. If a component depends on a discriminant, replace its subtype
339 -- using the discriminant values in the discriminant constraint. Subt
340 -- is the defining identifier for the subtype whose list of constrained
341 -- entities we will create. Decl_Node is the type declaration node where
342 -- we will attach all the itypes created. Typ is the base discriminated
343 -- type for the subtype Subt. Constraints is the list of discriminant
344 -- constraints for Typ.
346 function Constrain_Component_Type
348 Constrained_Typ : Entity_Id;
349 Related_Node : Node_Id;
351 Constraints : Elist_Id) return Entity_Id;
352 -- Given a discriminated base type Typ, a list of discriminant constraints,
353 -- Constraints, for Typ and a component Comp of Typ, create and return the
354 -- type corresponding to Etype (Comp) where all discriminant references
355 -- are replaced with the corresponding constraint. If Etype (Comp) contains
356 -- no discriminant references then it is returned as-is. Constrained_Typ
357 -- is the final constrained subtype to which the constrained component
358 -- belongs. Related_Node is the node where we attach all created itypes.
360 procedure Constrain_Access
361 (Def_Id : in out Entity_Id;
363 Related_Nod : Node_Id);
364 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
365 -- an anonymous type created for a subtype indication. In that case it is
366 -- created in the procedure and attached to Related_Nod.
368 procedure Constrain_Array
369 (Def_Id : in out Entity_Id;
371 Related_Nod : Node_Id;
372 Related_Id : Entity_Id;
374 -- Apply a list of index constraints to an unconstrained array type. The
375 -- first parameter is the entity for the resulting subtype. A value of
376 -- Empty for Def_Id indicates that an implicit type must be created, but
377 -- creation is delayed (and must be done by this procedure) because other
378 -- subsidiary implicit types must be created first (which is why Def_Id
379 -- is an in/out parameter). The second parameter is a subtype indication
380 -- node for the constrained array to be created (e.g. something of the
381 -- form string (1 .. 10)). Related_Nod gives the place where this type
382 -- has to be inserted in the tree. The Related_Id and Suffix parameters
383 -- are used to build the associated Implicit type name.
385 procedure Constrain_Concurrent
386 (Def_Id : in out Entity_Id;
388 Related_Nod : Node_Id;
389 Related_Id : Entity_Id;
391 -- Apply list of discriminant constraints to an unconstrained concurrent
394 -- SI is the N_Subtype_Indication node containing the constraint and
395 -- the unconstrained type to constrain.
397 -- Def_Id is the entity for the resulting constrained subtype. A value
398 -- of Empty for Def_Id indicates that an implicit type must be created,
399 -- but creation is delayed (and must be done by this procedure) because
400 -- other subsidiary implicit types must be created first (which is why
401 -- Def_Id is an in/out parameter).
403 -- Related_Nod gives the place where this type has to be inserted
406 -- The last two arguments are used to create its external name if needed.
408 function Constrain_Corresponding_Record
409 (Prot_Subt : Entity_Id;
410 Corr_Rec : Entity_Id;
411 Related_Nod : Node_Id) return Entity_Id;
412 -- When constraining a protected type or task type with discriminants,
413 -- constrain the corresponding record with the same discriminant values.
415 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
416 -- Constrain a decimal fixed point type with a digits constraint and/or a
417 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
419 procedure Constrain_Discriminated_Type
422 Related_Nod : Node_Id;
423 For_Access : Boolean := False);
424 -- Process discriminant constraints of composite type. Verify that values
425 -- have been provided for all discriminants, that the original type is
426 -- unconstrained, and that the types of the supplied expressions match
427 -- the discriminant types. The first three parameters are like in routine
428 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
431 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
432 -- Constrain an enumeration type with a range constraint. This is identical
433 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
435 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
436 -- Constrain a floating point type with either a digits constraint
437 -- and/or a range constraint, building a E_Floating_Point_Subtype.
439 procedure Constrain_Index
442 Related_Nod : Node_Id;
443 Related_Id : Entity_Id;
446 -- Process an index constraint S in a constrained array declaration. The
447 -- constraint can be a subtype name, or a range with or without an explicit
448 -- subtype mark. The index is the corresponding index of the unconstrained
449 -- array. The Related_Id and Suffix parameters are used to build the
450 -- associated Implicit type name.
452 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
453 -- Build subtype of a signed or modular integer type
455 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
456 -- Constrain an ordinary fixed point type with a range constraint, and
457 -- build an E_Ordinary_Fixed_Point_Subtype entity.
459 procedure Copy_And_Swap (Priv, Full : Entity_Id);
460 -- Copy the Priv entity into the entity of its full declaration then swap
461 -- the two entities in such a manner that the former private type is now
462 -- seen as a full type.
464 procedure Decimal_Fixed_Point_Type_Declaration
467 -- Create a new decimal fixed point type, and apply the constraint to
468 -- obtain a subtype of this new type.
470 procedure Complete_Private_Subtype
473 Full_Base : Entity_Id;
474 Related_Nod : Node_Id);
475 -- Complete the implicit full view of a private subtype by setting the
476 -- appropriate semantic fields. If the full view of the parent is a record
477 -- type, build constrained components of subtype.
479 procedure Derive_Progenitor_Subprograms
480 (Parent_Type : Entity_Id;
481 Tagged_Type : Entity_Id);
482 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
483 -- operations of progenitors of Tagged_Type, and replace the subsidiary
484 -- subtypes with Tagged_Type, to build the specs of the inherited interface
485 -- primitives. The derived primitives are aliased to those of the
486 -- interface. This routine takes care also of transferring to the full view
487 -- subprograms associated with the partial view of Tagged_Type that cover
488 -- interface primitives.
490 procedure Derived_Standard_Character
492 Parent_Type : Entity_Id;
493 Derived_Type : Entity_Id);
494 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
495 -- derivations from types Standard.Character and Standard.Wide_Character.
497 procedure Derived_Type_Declaration
500 Is_Completion : Boolean);
501 -- Process a derived type declaration. Build_Derived_Type is invoked
502 -- to process the actual derived type definition. Parameters N and
503 -- Is_Completion have the same meaning as in Build_Derived_Type.
504 -- T is the N_Defining_Identifier for the entity defined in the
505 -- N_Full_Type_Declaration node N, that is T is the derived type.
507 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
508 -- Insert each literal in symbol table, as an overloadable identifier. Each
509 -- enumeration type is mapped into a sequence of integers, and each literal
510 -- is defined as a constant with integer value. If any of the literals are
511 -- character literals, the type is a character type, which means that
512 -- strings are legal aggregates for arrays of components of the type.
514 function Expand_To_Stored_Constraint
516 Constraint : Elist_Id) return Elist_Id;
517 -- Given a constraint (i.e. a list of expressions) on the discriminants of
518 -- Typ, expand it into a constraint on the stored discriminants and return
519 -- the new list of expressions constraining the stored discriminants.
521 function Find_Type_Of_Object
523 Related_Nod : Node_Id) return Entity_Id;
524 -- Get type entity for object referenced by Obj_Def, attaching the implicit
525 -- types generated to Related_Nod.
527 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
528 -- Create a new float and apply the constraint to obtain subtype of it
530 function Has_Range_Constraint (N : Node_Id) return Boolean;
531 -- Given an N_Subtype_Indication node N, return True if a range constraint
532 -- is present, either directly, or as part of a digits or delta constraint.
533 -- In addition, a digits constraint in the decimal case returns True, since
534 -- it establishes a default range if no explicit range is present.
536 function Inherit_Components
538 Parent_Base : Entity_Id;
539 Derived_Base : Entity_Id;
541 Inherit_Discr : Boolean;
542 Discs : Elist_Id) return Elist_Id;
543 -- Called from Build_Derived_Record_Type to inherit the components of
544 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
545 -- For more information on derived types and component inheritance please
546 -- consult the comment above the body of Build_Derived_Record_Type.
548 -- N is the original derived type declaration
550 -- Is_Tagged is set if we are dealing with tagged types
552 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
553 -- Parent_Base, otherwise no discriminants are inherited.
555 -- Discs gives the list of constraints that apply to Parent_Base in the
556 -- derived type declaration. If Discs is set to No_Elist, then we have
557 -- the following situation:
559 -- type Parent (D1..Dn : ..) is [tagged] record ...;
560 -- type Derived is new Parent [with ...];
562 -- which gets treated as
564 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
566 -- For untagged types the returned value is an association list. The list
567 -- starts from the association (Parent_Base => Derived_Base), and then it
568 -- contains a sequence of the associations of the form
570 -- (Old_Component => New_Component),
572 -- where Old_Component is the Entity_Id of a component in Parent_Base and
573 -- New_Component is the Entity_Id of the corresponding component in
574 -- Derived_Base. For untagged records, this association list is needed when
575 -- copying the record declaration for the derived base. In the tagged case
576 -- the value returned is irrelevant.
578 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
579 -- Propagate static and dynamic predicate flags from a parent to the
580 -- subtype in a subtype declaration with and without constraints.
582 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
583 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
584 -- Determine whether subprogram Subp is a procedure subject to pragma
585 -- Extensions_Visible with value False and has at least one controlling
586 -- parameter of mode OUT.
588 function Is_Valid_Constraint_Kind
590 Constraint_Kind : Node_Kind) return Boolean;
591 -- Returns True if it is legal to apply the given kind of constraint to the
592 -- given kind of type (index constraint to an array type, for example).
594 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
595 -- Create new modular type. Verify that modulus is in bounds
597 procedure New_Concatenation_Op (Typ : Entity_Id);
598 -- Create an abbreviated declaration for an operator in order to
599 -- materialize concatenation on array types.
601 procedure Ordinary_Fixed_Point_Type_Declaration
604 -- Create a new ordinary fixed point type, and apply the constraint to
605 -- obtain subtype of it.
607 procedure Prepare_Private_Subtype_Completion
609 Related_Nod : Node_Id);
610 -- Id is a subtype of some private type. Creates the full declaration
611 -- associated with Id whenever possible, i.e. when the full declaration
612 -- of the base type is already known. Records each subtype into
613 -- Private_Dependents of the base type.
615 procedure Process_Incomplete_Dependents
619 -- Process all entities that depend on an incomplete type. There include
620 -- subtypes, subprogram types that mention the incomplete type in their
621 -- profiles, and subprogram with access parameters that designate the
624 -- Inc_T is the defining identifier of an incomplete type declaration, its
625 -- Ekind is E_Incomplete_Type.
627 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
629 -- Full_T is N's defining identifier.
631 -- Subtypes of incomplete types with discriminants are completed when the
632 -- parent type is. This is simpler than private subtypes, because they can
633 -- only appear in the same scope, and there is no need to exchange views.
634 -- Similarly, access_to_subprogram types may have a parameter or a return
635 -- type that is an incomplete type, and that must be replaced with the
638 -- If the full type is tagged, subprogram with access parameters that
639 -- designated the incomplete may be primitive operations of the full type,
640 -- and have to be processed accordingly.
642 procedure Process_Real_Range_Specification (Def : Node_Id);
643 -- Given the type definition for a real type, this procedure processes and
644 -- checks the real range specification of this type definition if one is
645 -- present. If errors are found, error messages are posted, and the
646 -- Real_Range_Specification of Def is reset to Empty.
648 procedure Record_Type_Declaration
652 -- Process a record type declaration (for both untagged and tagged
653 -- records). Parameters T and N are exactly like in procedure
654 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
655 -- for this routine. If this is the completion of an incomplete type
656 -- declaration, Prev is the entity of the incomplete declaration, used for
657 -- cross-referencing. Otherwise Prev = T.
659 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
660 -- This routine is used to process the actual record type definition (both
661 -- for untagged and tagged records). Def is a record type definition node.
662 -- This procedure analyzes the components in this record type definition.
663 -- Prev_T is the entity for the enclosing record type. It is provided so
664 -- that its Has_Task flag can be set if any of the component have Has_Task
665 -- set. If the declaration is the completion of an incomplete type
666 -- declaration, Prev_T is the original incomplete type, whose full view is
669 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
670 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
671 -- build a copy of the declaration tree of the parent, and we create
672 -- independently the list of components for the derived type. Semantic
673 -- information uses the component entities, but record representation
674 -- clauses are validated on the declaration tree. This procedure replaces
675 -- discriminants and components in the declaration with those that have
676 -- been created by Inherit_Components.
678 procedure Set_Fixed_Range
683 -- Build a range node with the given bounds and set it as the Scalar_Range
684 -- of the given fixed-point type entity. Loc is the source location used
685 -- for the constructed range. See body for further details.
687 procedure Set_Scalar_Range_For_Subtype
691 -- This routine is used to set the scalar range field for a subtype given
692 -- Def_Id, the entity for the subtype, and R, the range expression for the
693 -- scalar range. Subt provides the parent subtype to be used to analyze,
694 -- resolve, and check the given range.
696 procedure Set_Default_SSO (T : Entity_Id);
697 -- T is the entity for an array or record being declared. This procedure
698 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
699 -- to the setting of Opt.Default_SSO.
701 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
702 -- Create a new signed integer entity, and apply the constraint to obtain
703 -- the required first named subtype of this type.
705 procedure Set_Stored_Constraint_From_Discriminant_Constraint
707 -- E is some record type. This routine computes E's Stored_Constraint
708 -- from its Discriminant_Constraint.
710 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
711 -- Check that an entity in a list of progenitors is an interface,
712 -- emit error otherwise.
714 -----------------------
715 -- Access_Definition --
716 -----------------------
718 function Access_Definition
719 (Related_Nod : Node_Id;
720 N : Node_Id) return Entity_Id
722 Anon_Type : Entity_Id;
723 Anon_Scope : Entity_Id;
724 Desig_Type : Entity_Id;
725 Enclosing_Prot_Type : Entity_Id := Empty;
728 Check_SPARK_05_Restriction ("access type is not allowed", N);
730 if Is_Entry (Current_Scope)
731 and then Is_Task_Type (Etype (Scope (Current_Scope)))
733 Error_Msg_N ("task entries cannot have access parameters", N);
737 -- Ada 2005: For an object declaration the corresponding anonymous
738 -- type is declared in the current scope.
740 -- If the access definition is the return type of another access to
741 -- function, scope is the current one, because it is the one of the
742 -- current type declaration, except for the pathological case below.
744 if Nkind_In (Related_Nod, N_Object_Declaration,
745 N_Access_Function_Definition)
747 Anon_Scope := Current_Scope;
749 -- A pathological case: function returning access functions that
750 -- return access functions, etc. Each anonymous access type created
751 -- is in the enclosing scope of the outermost function.
758 while Nkind_In (Par, N_Access_Function_Definition,
764 if Nkind (Par) = N_Function_Specification then
765 Anon_Scope := Scope (Defining_Entity (Par));
769 -- For the anonymous function result case, retrieve the scope of the
770 -- function specification's associated entity rather than using the
771 -- current scope. The current scope will be the function itself if the
772 -- formal part is currently being analyzed, but will be the parent scope
773 -- in the case of a parameterless function, and we always want to use
774 -- the function's parent scope. Finally, if the function is a child
775 -- unit, we must traverse the tree to retrieve the proper entity.
777 elsif Nkind (Related_Nod) = N_Function_Specification
778 and then Nkind (Parent (N)) /= N_Parameter_Specification
780 -- If the current scope is a protected type, the anonymous access
781 -- is associated with one of the protected operations, and must
782 -- be available in the scope that encloses the protected declaration.
783 -- Otherwise the type is in the scope enclosing the subprogram.
785 -- If the function has formals, The return type of a subprogram
786 -- declaration is analyzed in the scope of the subprogram (see
787 -- Process_Formals) and thus the protected type, if present, is
788 -- the scope of the current function scope.
790 if Ekind (Current_Scope) = E_Protected_Type then
791 Enclosing_Prot_Type := Current_Scope;
793 elsif Ekind (Current_Scope) = E_Function
794 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
796 Enclosing_Prot_Type := Scope (Current_Scope);
799 if Present (Enclosing_Prot_Type) then
800 Anon_Scope := Scope (Enclosing_Prot_Type);
803 Anon_Scope := Scope (Defining_Entity (Related_Nod));
806 -- For an access type definition, if the current scope is a child
807 -- unit it is the scope of the type.
809 elsif Is_Compilation_Unit (Current_Scope) then
810 Anon_Scope := Current_Scope;
812 -- For access formals, access components, and access discriminants, the
813 -- scope is that of the enclosing declaration,
816 Anon_Scope := Scope (Current_Scope);
821 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
824 and then Ada_Version >= Ada_2005
826 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
829 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
830 -- the corresponding semantic routine
832 if Present (Access_To_Subprogram_Definition (N)) then
834 -- Compiler runtime units are compiled in Ada 2005 mode when building
835 -- the runtime library but must also be compilable in Ada 95 mode
836 -- (when bootstrapping the compiler).
838 Check_Compiler_Unit ("anonymous access to subprogram", N);
840 Access_Subprogram_Declaration
841 (T_Name => Anon_Type,
842 T_Def => Access_To_Subprogram_Definition (N));
844 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
846 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
848 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
851 Set_Can_Use_Internal_Rep
852 (Anon_Type, not Always_Compatible_Rep_On_Target);
854 -- If the anonymous access is associated with a protected operation,
855 -- create a reference to it after the enclosing protected definition
856 -- because the itype will be used in the subsequent bodies.
858 -- If the anonymous access itself is protected, a full type
859 -- declaratiton will be created for it, so that the equivalent
860 -- record type can be constructed. For further details, see
861 -- Replace_Anonymous_Access_To_Protected-Subprogram.
863 if Ekind (Current_Scope) = E_Protected_Type
864 and then not Protected_Present (Access_To_Subprogram_Definition (N))
866 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
872 Find_Type (Subtype_Mark (N));
873 Desig_Type := Entity (Subtype_Mark (N));
875 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
876 Set_Etype (Anon_Type, Anon_Type);
878 -- Make sure the anonymous access type has size and alignment fields
879 -- set, as required by gigi. This is necessary in the case of the
880 -- Task_Body_Procedure.
882 if not Has_Private_Component (Desig_Type) then
883 Layout_Type (Anon_Type);
886 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
887 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
888 -- the null value is allowed. In Ada 95 the null value is never allowed.
890 if Ada_Version >= Ada_2005 then
891 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
893 Set_Can_Never_Be_Null (Anon_Type, True);
896 -- The anonymous access type is as public as the discriminated type or
897 -- subprogram that defines it. It is imported (for back-end purposes)
898 -- if the designated type is.
900 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
902 -- Ada 2005 (AI-231): Propagate the access-constant attribute
904 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
906 -- The context is either a subprogram declaration, object declaration,
907 -- or an access discriminant, in a private or a full type declaration.
908 -- In the case of a subprogram, if the designated type is incomplete,
909 -- the operation will be a primitive operation of the full type, to be
910 -- updated subsequently. If the type is imported through a limited_with
911 -- clause, the subprogram is not a primitive operation of the type
912 -- (which is declared elsewhere in some other scope).
914 if Ekind (Desig_Type) = E_Incomplete_Type
915 and then not From_Limited_With (Desig_Type)
916 and then Is_Overloadable (Current_Scope)
918 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
919 Set_Has_Delayed_Freeze (Current_Scope);
922 -- Ada 2005: If the designated type is an interface that may contain
923 -- tasks, create a Master entity for the declaration. This must be done
924 -- before expansion of the full declaration, because the declaration may
925 -- include an expression that is an allocator, whose expansion needs the
926 -- proper Master for the created tasks.
928 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
930 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
932 Build_Class_Wide_Master (Anon_Type);
934 -- Similarly, if the type is an anonymous access that designates
935 -- tasks, create a master entity for it in the current context.
937 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
939 Build_Master_Entity (Defining_Identifier (Related_Nod));
940 Build_Master_Renaming (Anon_Type);
944 -- For a private component of a protected type, it is imperative that
945 -- the back-end elaborate the type immediately after the protected
946 -- declaration, because this type will be used in the declarations
947 -- created for the component within each protected body, so we must
948 -- create an itype reference for it now.
950 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
951 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
953 -- Similarly, if the access definition is the return result of a
954 -- function, create an itype reference for it because it will be used
955 -- within the function body. For a regular function that is not a
956 -- compilation unit, insert reference after the declaration. For a
957 -- protected operation, insert it after the enclosing protected type
958 -- declaration. In either case, do not create a reference for a type
959 -- obtained through a limited_with clause, because this would introduce
960 -- semantic dependencies.
962 -- Similarly, do not create a reference if the designated type is a
963 -- generic formal, because no use of it will reach the backend.
965 elsif Nkind (Related_Nod) = N_Function_Specification
966 and then not From_Limited_With (Desig_Type)
967 and then not Is_Generic_Type (Desig_Type)
969 if Present (Enclosing_Prot_Type) then
970 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
972 elsif Is_List_Member (Parent (Related_Nod))
973 and then Nkind (Parent (N)) /= N_Parameter_Specification
975 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
978 -- Finally, create an itype reference for an object declaration of an
979 -- anonymous access type. This is strictly necessary only for deferred
980 -- constants, but in any case will avoid out-of-scope problems in the
983 elsif Nkind (Related_Nod) = N_Object_Declaration then
984 Build_Itype_Reference (Anon_Type, Related_Nod);
988 end Access_Definition;
990 -----------------------------------
991 -- Access_Subprogram_Declaration --
992 -----------------------------------
994 procedure Access_Subprogram_Declaration
998 procedure Check_For_Premature_Usage (Def : Node_Id);
999 -- Check that type T_Name is not used, directly or recursively, as a
1000 -- parameter or a return type in Def. Def is either a subtype, an
1001 -- access_definition, or an access_to_subprogram_definition.
1003 -------------------------------
1004 -- Check_For_Premature_Usage --
1005 -------------------------------
1007 procedure Check_For_Premature_Usage (Def : Node_Id) is
1011 -- Check for a subtype mark
1013 if Nkind (Def) in N_Has_Etype then
1014 if Etype (Def) = T_Name then
1016 ("type& cannot be used before end of its declaration", Def);
1019 -- If this is not a subtype, then this is an access_definition
1021 elsif Nkind (Def) = N_Access_Definition then
1022 if Present (Access_To_Subprogram_Definition (Def)) then
1023 Check_For_Premature_Usage
1024 (Access_To_Subprogram_Definition (Def));
1026 Check_For_Premature_Usage (Subtype_Mark (Def));
1029 -- The only cases left are N_Access_Function_Definition and
1030 -- N_Access_Procedure_Definition.
1033 if Present (Parameter_Specifications (Def)) then
1034 Param := First (Parameter_Specifications (Def));
1035 while Present (Param) loop
1036 Check_For_Premature_Usage (Parameter_Type (Param));
1037 Param := Next (Param);
1041 if Nkind (Def) = N_Access_Function_Definition then
1042 Check_For_Premature_Usage (Result_Definition (Def));
1045 end Check_For_Premature_Usage;
1049 Formals : constant List_Id := Parameter_Specifications (T_Def);
1052 Desig_Type : constant Entity_Id :=
1053 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1055 -- Start of processing for Access_Subprogram_Declaration
1058 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1060 -- Associate the Itype node with the inner full-type declaration or
1061 -- subprogram spec or entry body. This is required to handle nested
1062 -- anonymous declarations. For example:
1065 -- (X : access procedure
1066 -- (Y : access procedure
1069 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1070 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1071 N_Private_Type_Declaration,
1072 N_Private_Extension_Declaration,
1073 N_Procedure_Specification,
1074 N_Function_Specification,
1078 Nkind_In (D_Ityp, N_Object_Declaration,
1079 N_Object_Renaming_Declaration,
1080 N_Formal_Object_Declaration,
1081 N_Formal_Type_Declaration,
1082 N_Task_Type_Declaration,
1083 N_Protected_Type_Declaration))
1085 D_Ityp := Parent (D_Ityp);
1086 pragma Assert (D_Ityp /= Empty);
1089 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1091 if Nkind_In (D_Ityp, N_Procedure_Specification,
1092 N_Function_Specification)
1094 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1096 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1097 N_Object_Declaration,
1098 N_Object_Renaming_Declaration,
1099 N_Formal_Type_Declaration)
1101 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1104 if Nkind (T_Def) = N_Access_Function_Definition then
1105 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1107 Acc : constant Node_Id := Result_Definition (T_Def);
1110 if Present (Access_To_Subprogram_Definition (Acc))
1112 Protected_Present (Access_To_Subprogram_Definition (Acc))
1116 Replace_Anonymous_Access_To_Protected_Subprogram
1122 Access_Definition (T_Def, Result_Definition (T_Def)));
1127 Analyze (Result_Definition (T_Def));
1130 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1133 -- If a null exclusion is imposed on the result type, then
1134 -- create a null-excluding itype (an access subtype) and use
1135 -- it as the function's Etype.
1137 if Is_Access_Type (Typ)
1138 and then Null_Exclusion_In_Return_Present (T_Def)
1140 Set_Etype (Desig_Type,
1141 Create_Null_Excluding_Itype
1143 Related_Nod => T_Def,
1144 Scope_Id => Current_Scope));
1147 if From_Limited_With (Typ) then
1149 -- AI05-151: Incomplete types are allowed in all basic
1150 -- declarations, including access to subprograms.
1152 if Ada_Version >= Ada_2012 then
1157 ("illegal use of incomplete type&",
1158 Result_Definition (T_Def), Typ);
1161 elsif Ekind (Current_Scope) = E_Package
1162 and then In_Private_Part (Current_Scope)
1164 if Ekind (Typ) = E_Incomplete_Type then
1165 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1167 elsif Is_Class_Wide_Type (Typ)
1168 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1171 (Desig_Type, Private_Dependents (Etype (Typ)));
1175 Set_Etype (Desig_Type, Typ);
1180 if not (Is_Type (Etype (Desig_Type))) then
1182 ("expect type in function specification",
1183 Result_Definition (T_Def));
1187 Set_Etype (Desig_Type, Standard_Void_Type);
1190 if Present (Formals) then
1191 Push_Scope (Desig_Type);
1193 -- Some special tests here. These special tests can be removed
1194 -- if and when Itypes always have proper parent pointers to their
1197 -- Special test 1) Link defining_identifier of formals. Required by
1198 -- First_Formal to provide its functionality.
1204 F := First (Formals);
1206 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1207 -- when it is part of an unconstrained type and subtype expansion
1208 -- is disabled. To avoid back-end problems with shared profiles,
1209 -- use previous subprogram type as the designated type, and then
1210 -- remove scope added above.
1212 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1214 Set_Etype (T_Name, T_Name);
1215 Init_Size_Align (T_Name);
1216 Set_Directly_Designated_Type (T_Name,
1217 Scope (Defining_Identifier (F)));
1222 while Present (F) loop
1223 if No (Parent (Defining_Identifier (F))) then
1224 Set_Parent (Defining_Identifier (F), F);
1231 Process_Formals (Formals, Parent (T_Def));
1233 -- Special test 2) End_Scope requires that the parent pointer be set
1234 -- to something reasonable, but Itypes don't have parent pointers. So
1235 -- we set it and then unset it ???
1237 Set_Parent (Desig_Type, T_Name);
1239 Set_Parent (Desig_Type, Empty);
1242 -- Check for premature usage of the type being defined
1244 Check_For_Premature_Usage (T_Def);
1246 -- The return type and/or any parameter type may be incomplete. Mark the
1247 -- subprogram_type as depending on the incomplete type, so that it can
1248 -- be updated when the full type declaration is seen. This only applies
1249 -- to incomplete types declared in some enclosing scope, not to limited
1250 -- views from other packages.
1252 -- Prior to Ada 2012, access to functions can only have in_parameters.
1254 if Present (Formals) then
1255 Formal := First_Formal (Desig_Type);
1256 while Present (Formal) loop
1257 if Ekind (Formal) /= E_In_Parameter
1258 and then Nkind (T_Def) = N_Access_Function_Definition
1259 and then Ada_Version < Ada_2012
1261 Error_Msg_N ("functions can only have IN parameters", Formal);
1264 if Ekind (Etype (Formal)) = E_Incomplete_Type
1265 and then In_Open_Scopes (Scope (Etype (Formal)))
1267 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1268 Set_Has_Delayed_Freeze (Desig_Type);
1271 Next_Formal (Formal);
1275 -- Check whether an indirect call without actuals may be possible. This
1276 -- is used when resolving calls whose result is then indexed.
1278 May_Need_Actuals (Desig_Type);
1280 -- If the return type is incomplete, this is legal as long as the type
1281 -- is declared in the current scope and will be completed in it (rather
1282 -- than being part of limited view).
1284 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1285 and then not Has_Delayed_Freeze (Desig_Type)
1286 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1288 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1289 Set_Has_Delayed_Freeze (Desig_Type);
1292 Check_Delayed_Subprogram (Desig_Type);
1294 if Protected_Present (T_Def) then
1295 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1296 Set_Convention (Desig_Type, Convention_Protected);
1298 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1301 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1303 Set_Etype (T_Name, T_Name);
1304 Init_Size_Align (T_Name);
1305 Set_Directly_Designated_Type (T_Name, Desig_Type);
1307 Generate_Reference_To_Formals (T_Name);
1309 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1311 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1313 Check_Restriction (No_Access_Subprograms, T_Def);
1314 end Access_Subprogram_Declaration;
1316 ----------------------------
1317 -- Access_Type_Declaration --
1318 ----------------------------
1320 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1321 P : constant Node_Id := Parent (Def);
1322 S : constant Node_Id := Subtype_Indication (Def);
1324 Full_Desig : Entity_Id;
1327 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1329 -- Check for permissible use of incomplete type
1331 if Nkind (S) /= N_Subtype_Indication then
1334 if Present (Entity (S))
1335 and then Ekind (Root_Type (Entity (S))) = E_Incomplete_Type
1337 Set_Directly_Designated_Type (T, Entity (S));
1339 -- If the designated type is a limited view, we cannot tell if
1340 -- the full view contains tasks, and there is no way to handle
1341 -- that full view in a client. We create a master entity for the
1342 -- scope, which will be used when a client determines that one
1345 if From_Limited_With (Entity (S))
1346 and then not Is_Class_Wide_Type (Entity (S))
1348 Set_Ekind (T, E_Access_Type);
1349 Build_Master_Entity (T);
1350 Build_Master_Renaming (T);
1354 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1357 -- If the access definition is of the form: ACCESS NOT NULL ..
1358 -- the subtype indication must be of an access type. Create
1359 -- a null-excluding subtype of it.
1361 if Null_Excluding_Subtype (Def) then
1362 if not Is_Access_Type (Entity (S)) then
1363 Error_Msg_N ("null exclusion must apply to access type", Def);
1367 Loc : constant Source_Ptr := Sloc (S);
1369 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1373 Make_Subtype_Declaration (Loc,
1374 Defining_Identifier => Nam,
1375 Subtype_Indication =>
1376 New_Occurrence_Of (Entity (S), Loc));
1377 Set_Null_Exclusion_Present (Decl);
1378 Insert_Before (Parent (Def), Decl);
1380 Set_Entity (S, Nam);
1386 Set_Directly_Designated_Type (T,
1387 Process_Subtype (S, P, T, 'P'));
1390 if All_Present (Def) or Constant_Present (Def) then
1391 Set_Ekind (T, E_General_Access_Type);
1393 Set_Ekind (T, E_Access_Type);
1396 Full_Desig := Designated_Type (T);
1398 if Base_Type (Full_Desig) = T then
1399 Error_Msg_N ("access type cannot designate itself", S);
1401 -- In Ada 2005, the type may have a limited view through some unit in
1402 -- its own context, allowing the following circularity that cannot be
1403 -- detected earlier.
1405 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1408 ("access type cannot designate its own class-wide type", S);
1410 -- Clean up indication of tagged status to prevent cascaded errors
1412 Set_Is_Tagged_Type (T, False);
1417 -- If the type has appeared already in a with_type clause, it is frozen
1418 -- and the pointer size is already set. Else, initialize.
1420 if not From_Limited_With (T) then
1421 Init_Size_Align (T);
1424 -- Note that Has_Task is always false, since the access type itself
1425 -- is not a task type. See Einfo for more description on this point.
1426 -- Exactly the same consideration applies to Has_Controlled_Component
1427 -- and to Has_Protected.
1429 Set_Has_Task (T, False);
1430 Set_Has_Protected (T, False);
1431 Set_Has_Timing_Event (T, False);
1432 Set_Has_Controlled_Component (T, False);
1434 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1435 -- problems where an incomplete view of this entity has been previously
1436 -- established by a limited with and an overlaid version of this field
1437 -- (Stored_Constraint) was initialized for the incomplete view.
1439 -- This reset is performed in most cases except where the access type
1440 -- has been created for the purposes of allocating or deallocating a
1441 -- build-in-place object. Such access types have explicitly set pools
1442 -- and finalization masters.
1444 if No (Associated_Storage_Pool (T)) then
1445 Set_Finalization_Master (T, Empty);
1448 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1451 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1452 Set_Is_Access_Constant (T, Constant_Present (Def));
1453 end Access_Type_Declaration;
1455 ----------------------------------
1456 -- Add_Interface_Tag_Components --
1457 ----------------------------------
1459 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1460 Loc : constant Source_Ptr := Sloc (N);
1464 procedure Add_Tag (Iface : Entity_Id);
1465 -- Add tag for one of the progenitor interfaces
1471 procedure Add_Tag (Iface : Entity_Id) is
1478 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1480 -- This is a reasonable place to propagate predicates
1482 if Has_Predicates (Iface) then
1483 Set_Has_Predicates (Typ);
1487 Make_Component_Definition (Loc,
1488 Aliased_Present => True,
1489 Subtype_Indication =>
1490 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1492 Tag := Make_Temporary (Loc, 'V');
1495 Make_Component_Declaration (Loc,
1496 Defining_Identifier => Tag,
1497 Component_Definition => Def);
1499 Analyze_Component_Declaration (Decl);
1501 Set_Analyzed (Decl);
1502 Set_Ekind (Tag, E_Component);
1504 Set_Is_Aliased (Tag);
1505 Set_Related_Type (Tag, Iface);
1506 Init_Component_Location (Tag);
1508 pragma Assert (Is_Frozen (Iface));
1510 Set_DT_Entry_Count (Tag,
1511 DT_Entry_Count (First_Entity (Iface)));
1513 if No (Last_Tag) then
1516 Insert_After (Last_Tag, Decl);
1521 -- If the ancestor has discriminants we need to give special support
1522 -- to store the offset_to_top value of the secondary dispatch tables.
1523 -- For this purpose we add a supplementary component just after the
1524 -- field that contains the tag associated with each secondary DT.
1526 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1528 Make_Component_Definition (Loc,
1529 Subtype_Indication =>
1530 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1532 Offset := Make_Temporary (Loc, 'V');
1535 Make_Component_Declaration (Loc,
1536 Defining_Identifier => Offset,
1537 Component_Definition => Def);
1539 Analyze_Component_Declaration (Decl);
1541 Set_Analyzed (Decl);
1542 Set_Ekind (Offset, E_Component);
1543 Set_Is_Aliased (Offset);
1544 Set_Related_Type (Offset, Iface);
1545 Init_Component_Location (Offset);
1546 Insert_After (Last_Tag, Decl);
1557 -- Start of processing for Add_Interface_Tag_Components
1560 if not RTE_Available (RE_Interface_Tag) then
1562 ("(Ada 2005) interface types not supported by this run-time!",
1567 if Ekind (Typ) /= E_Record_Type
1568 or else (Is_Concurrent_Record_Type (Typ)
1569 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1570 or else (not Is_Concurrent_Record_Type (Typ)
1571 and then No (Interfaces (Typ))
1572 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1577 -- Find the current last tag
1579 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1580 Ext := Record_Extension_Part (Type_Definition (N));
1582 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1583 Ext := Type_Definition (N);
1588 if not (Present (Component_List (Ext))) then
1589 Set_Null_Present (Ext, False);
1591 Set_Component_List (Ext,
1592 Make_Component_List (Loc,
1593 Component_Items => L,
1594 Null_Present => False));
1596 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1597 L := Component_Items
1599 (Record_Extension_Part
1600 (Type_Definition (N))));
1602 L := Component_Items
1604 (Type_Definition (N)));
1607 -- Find the last tag component
1610 while Present (Comp) loop
1611 if Nkind (Comp) = N_Component_Declaration
1612 and then Is_Tag (Defining_Identifier (Comp))
1621 -- At this point L references the list of components and Last_Tag
1622 -- references the current last tag (if any). Now we add the tag
1623 -- corresponding with all the interfaces that are not implemented
1626 if Present (Interfaces (Typ)) then
1627 Elmt := First_Elmt (Interfaces (Typ));
1628 while Present (Elmt) loop
1629 Add_Tag (Node (Elmt));
1633 end Add_Interface_Tag_Components;
1635 -------------------------------------
1636 -- Add_Internal_Interface_Entities --
1637 -------------------------------------
1639 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1642 Iface_Elmt : Elmt_Id;
1643 Iface_Prim : Entity_Id;
1644 Ifaces_List : Elist_Id;
1645 New_Subp : Entity_Id := Empty;
1647 Restore_Scope : Boolean := False;
1650 pragma Assert (Ada_Version >= Ada_2005
1651 and then Is_Record_Type (Tagged_Type)
1652 and then Is_Tagged_Type (Tagged_Type)
1653 and then Has_Interfaces (Tagged_Type)
1654 and then not Is_Interface (Tagged_Type));
1656 -- Ensure that the internal entities are added to the scope of the type
1658 if Scope (Tagged_Type) /= Current_Scope then
1659 Push_Scope (Scope (Tagged_Type));
1660 Restore_Scope := True;
1663 Collect_Interfaces (Tagged_Type, Ifaces_List);
1665 Iface_Elmt := First_Elmt (Ifaces_List);
1666 while Present (Iface_Elmt) loop
1667 Iface := Node (Iface_Elmt);
1669 -- Originally we excluded here from this processing interfaces that
1670 -- are parents of Tagged_Type because their primitives are located
1671 -- in the primary dispatch table (and hence no auxiliary internal
1672 -- entities are required to handle secondary dispatch tables in such
1673 -- case). However, these auxiliary entities are also required to
1674 -- handle derivations of interfaces in formals of generics (see
1675 -- Derive_Subprograms).
1677 Elmt := First_Elmt (Primitive_Operations (Iface));
1678 while Present (Elmt) loop
1679 Iface_Prim := Node (Elmt);
1681 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1683 Find_Primitive_Covering_Interface
1684 (Tagged_Type => Tagged_Type,
1685 Iface_Prim => Iface_Prim);
1687 if No (Prim) and then Serious_Errors_Detected > 0 then
1691 pragma Assert (Present (Prim));
1693 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1694 -- differs from the name of the interface primitive then it is
1695 -- a private primitive inherited from a parent type. In such
1696 -- case, given that Tagged_Type covers the interface, the
1697 -- inherited private primitive becomes visible. For such
1698 -- purpose we add a new entity that renames the inherited
1699 -- private primitive.
1701 if Chars (Prim) /= Chars (Iface_Prim) then
1702 pragma Assert (Has_Suffix (Prim, 'P'));
1704 (New_Subp => New_Subp,
1705 Parent_Subp => Iface_Prim,
1706 Derived_Type => Tagged_Type,
1707 Parent_Type => Iface);
1708 Set_Alias (New_Subp, Prim);
1709 Set_Is_Abstract_Subprogram
1710 (New_Subp, Is_Abstract_Subprogram (Prim));
1714 (New_Subp => New_Subp,
1715 Parent_Subp => Iface_Prim,
1716 Derived_Type => Tagged_Type,
1717 Parent_Type => Iface);
1722 if Is_Inherited_Operation (Prim)
1723 and then Present (Alias (Prim))
1725 Anc := Alias (Prim);
1727 Anc := Overridden_Operation (Prim);
1730 -- Apply legality checks in RM 6.1.1 (10-13) concerning
1731 -- nonconforming preconditions in both an ancestor and
1732 -- a progenitor operation.
1735 and then Has_Non_Trivial_Precondition (Anc)
1736 and then Has_Non_Trivial_Precondition (Iface_Prim)
1738 if Is_Abstract_Subprogram (Prim)
1740 (Ekind (Prim) = E_Procedure
1741 and then Nkind (Parent (Prim)) =
1742 N_Procedure_Specification
1743 and then Null_Present (Parent (Prim)))
1747 -- The inherited operation must be overridden
1749 elsif not Comes_From_Source (Prim) then
1751 ("&inherits non-conforming preconditions and must "
1752 & "be overridden (RM 6.1.1 (10-16)",
1753 Parent (Tagged_Type), Prim);
1758 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1759 -- associated with interface types. These entities are
1760 -- only registered in the list of primitives of its
1761 -- corresponding tagged type because they are only used
1762 -- to fill the contents of the secondary dispatch tables.
1763 -- Therefore they are removed from the homonym chains.
1765 Set_Is_Hidden (New_Subp);
1766 Set_Is_Internal (New_Subp);
1767 Set_Alias (New_Subp, Prim);
1768 Set_Is_Abstract_Subprogram
1769 (New_Subp, Is_Abstract_Subprogram (Prim));
1770 Set_Interface_Alias (New_Subp, Iface_Prim);
1772 -- If the returned type is an interface then propagate it to
1773 -- the returned type. Needed by the thunk to generate the code
1774 -- which displaces "this" to reference the corresponding
1775 -- secondary dispatch table in the returned object.
1777 if Is_Interface (Etype (Iface_Prim)) then
1778 Set_Etype (New_Subp, Etype (Iface_Prim));
1781 -- Internal entities associated with interface types are only
1782 -- registered in the list of primitives of the tagged type.
1783 -- They are only used to fill the contents of the secondary
1784 -- dispatch tables. Therefore they are not needed in the
1787 Remove_Homonym (New_Subp);
1789 -- Hidden entities associated with interfaces must have set
1790 -- the Has_Delay_Freeze attribute to ensure that, in case
1791 -- of locally defined tagged types (or compiling with static
1792 -- dispatch tables generation disabled) the corresponding
1793 -- entry of the secondary dispatch table is filled when such
1794 -- an entity is frozen. This is an expansion activity that must
1795 -- be suppressed for ASIS because it leads to gigi elaboration
1796 -- issues in annotate mode.
1798 if not ASIS_Mode then
1799 Set_Has_Delayed_Freeze (New_Subp);
1807 Next_Elmt (Iface_Elmt);
1810 if Restore_Scope then
1813 end Add_Internal_Interface_Entities;
1815 -----------------------------------
1816 -- Analyze_Component_Declaration --
1817 -----------------------------------
1819 procedure Analyze_Component_Declaration (N : Node_Id) is
1820 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1821 Id : constant Entity_Id := Defining_Identifier (N);
1822 E : constant Node_Id := Expression (N);
1823 Typ : constant Node_Id :=
1824 Subtype_Indication (Component_Definition (N));
1828 function Contains_POC (Constr : Node_Id) return Boolean;
1829 -- Determines whether a constraint uses the discriminant of a record
1830 -- type thus becoming a per-object constraint (POC).
1832 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1833 -- Typ is the type of the current component, check whether this type is
1834 -- a limited type. Used to validate declaration against that of
1835 -- enclosing record.
1841 function Contains_POC (Constr : Node_Id) return Boolean is
1843 -- Prevent cascaded errors
1845 if Error_Posted (Constr) then
1849 case Nkind (Constr) is
1850 when N_Attribute_Reference =>
1851 return Attribute_Name (Constr) = Name_Access
1852 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1854 when N_Discriminant_Association =>
1855 return Denotes_Discriminant (Expression (Constr));
1857 when N_Identifier =>
1858 return Denotes_Discriminant (Constr);
1860 when N_Index_Or_Discriminant_Constraint =>
1865 IDC := First (Constraints (Constr));
1866 while Present (IDC) loop
1868 -- One per-object constraint is sufficient
1870 if Contains_POC (IDC) then
1881 return Denotes_Discriminant (Low_Bound (Constr))
1883 Denotes_Discriminant (High_Bound (Constr));
1885 when N_Range_Constraint =>
1886 return Denotes_Discriminant (Range_Expression (Constr));
1893 ----------------------
1894 -- Is_Known_Limited --
1895 ----------------------
1897 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1898 P : constant Entity_Id := Etype (Typ);
1899 R : constant Entity_Id := Root_Type (Typ);
1902 if Is_Limited_Record (Typ) then
1905 -- If the root type is limited (and not a limited interface)
1906 -- so is the current type
1908 elsif Is_Limited_Record (R)
1909 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1913 -- Else the type may have a limited interface progenitor, but a
1914 -- limited record parent.
1916 elsif R /= P and then Is_Limited_Record (P) then
1922 end Is_Known_Limited;
1924 -- Start of processing for Analyze_Component_Declaration
1927 Generate_Definition (Id);
1930 if Present (Typ) then
1931 T := Find_Type_Of_Object
1932 (Subtype_Indication (Component_Definition (N)), N);
1934 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1935 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1938 -- Ada 2005 (AI-230): Access Definition case
1941 pragma Assert (Present
1942 (Access_Definition (Component_Definition (N))));
1944 T := Access_Definition
1946 N => Access_Definition (Component_Definition (N)));
1947 Set_Is_Local_Anonymous_Access (T);
1949 -- Ada 2005 (AI-254)
1951 if Present (Access_To_Subprogram_Definition
1952 (Access_Definition (Component_Definition (N))))
1953 and then Protected_Present (Access_To_Subprogram_Definition
1955 (Component_Definition (N))))
1957 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1961 -- If the subtype is a constrained subtype of the enclosing record,
1962 -- (which must have a partial view) the back-end does not properly
1963 -- handle the recursion. Rewrite the component declaration with an
1964 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1965 -- the tree directly because side effects have already been removed from
1966 -- discriminant constraints.
1968 if Ekind (T) = E_Access_Subtype
1969 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1970 and then Comes_From_Source (T)
1971 and then Nkind (Parent (T)) = N_Subtype_Declaration
1972 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1975 (Subtype_Indication (Component_Definition (N)),
1976 New_Copy_Tree (Subtype_Indication (Parent (T))));
1977 T := Find_Type_Of_Object
1978 (Subtype_Indication (Component_Definition (N)), N);
1981 -- If the component declaration includes a default expression, then we
1982 -- check that the component is not of a limited type (RM 3.7(5)),
1983 -- and do the special preanalysis of the expression (see section on
1984 -- "Handling of Default and Per-Object Expressions" in the spec of
1988 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1989 Preanalyze_Default_Expression (E, T);
1990 Check_Initialization (T, E);
1992 if Ada_Version >= Ada_2005
1993 and then Ekind (T) = E_Anonymous_Access_Type
1994 and then Etype (E) /= Any_Type
1996 -- Check RM 3.9.2(9): "if the expected type for an expression is
1997 -- an anonymous access-to-specific tagged type, then the object
1998 -- designated by the expression shall not be dynamically tagged
1999 -- unless it is a controlling operand in a call on a dispatching
2002 if Is_Tagged_Type (Directly_Designated_Type (T))
2004 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
2006 Ekind (Directly_Designated_Type (Etype (E))) =
2010 ("access to specific tagged type required (RM 3.9.2(9))", E);
2013 -- (Ada 2005: AI-230): Accessibility check for anonymous
2016 if Type_Access_Level (Etype (E)) >
2017 Deepest_Type_Access_Level (T)
2020 ("expression has deeper access level than component " &
2021 "(RM 3.10.2 (12.2))", E);
2024 -- The initialization expression is a reference to an access
2025 -- discriminant. The type of the discriminant is always deeper
2026 -- than any access type.
2028 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2029 and then Is_Entity_Name (E)
2030 and then Ekind (Entity (E)) = E_In_Parameter
2031 and then Present (Discriminal_Link (Entity (E)))
2034 ("discriminant has deeper accessibility level than target",
2040 -- The parent type may be a private view with unknown discriminants,
2041 -- and thus unconstrained. Regular components must be constrained.
2043 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2044 if Is_Class_Wide_Type (T) then
2046 ("class-wide subtype with unknown discriminants" &
2047 " in component declaration",
2048 Subtype_Indication (Component_Definition (N)));
2051 ("unconstrained subtype in component declaration",
2052 Subtype_Indication (Component_Definition (N)));
2055 -- Components cannot be abstract, except for the special case of
2056 -- the _Parent field (case of extending an abstract tagged type)
2058 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2059 Error_Msg_N ("type of a component cannot be abstract", N);
2063 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2065 -- The component declaration may have a per-object constraint, set
2066 -- the appropriate flag in the defining identifier of the subtype.
2068 if Present (Subtype_Indication (Component_Definition (N))) then
2070 Sindic : constant Node_Id :=
2071 Subtype_Indication (Component_Definition (N));
2073 if Nkind (Sindic) = N_Subtype_Indication
2074 and then Present (Constraint (Sindic))
2075 and then Contains_POC (Constraint (Sindic))
2077 Set_Has_Per_Object_Constraint (Id);
2082 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2083 -- out some static checks.
2085 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2086 Null_Exclusion_Static_Checks (N);
2089 -- If this component is private (or depends on a private type), flag the
2090 -- record type to indicate that some operations are not available.
2092 P := Private_Component (T);
2096 -- Check for circular definitions
2098 if P = Any_Type then
2099 Set_Etype (Id, Any_Type);
2101 -- There is a gap in the visibility of operations only if the
2102 -- component type is not defined in the scope of the record type.
2104 elsif Scope (P) = Scope (Current_Scope) then
2107 elsif Is_Limited_Type (P) then
2108 Set_Is_Limited_Composite (Current_Scope);
2111 Set_Is_Private_Composite (Current_Scope);
2116 and then Is_Limited_Type (T)
2117 and then Chars (Id) /= Name_uParent
2118 and then Is_Tagged_Type (Current_Scope)
2120 if Is_Derived_Type (Current_Scope)
2121 and then not Is_Known_Limited (Current_Scope)
2124 ("extension of nonlimited type cannot have limited components",
2127 if Is_Interface (Root_Type (Current_Scope)) then
2129 ("\limitedness is not inherited from limited interface", N);
2130 Error_Msg_N ("\add LIMITED to type indication", N);
2133 Explain_Limited_Type (T, N);
2134 Set_Etype (Id, Any_Type);
2135 Set_Is_Limited_Composite (Current_Scope, False);
2137 elsif not Is_Derived_Type (Current_Scope)
2138 and then not Is_Limited_Record (Current_Scope)
2139 and then not Is_Concurrent_Type (Current_Scope)
2142 ("nonlimited tagged type cannot have limited components", N);
2143 Explain_Limited_Type (T, N);
2144 Set_Etype (Id, Any_Type);
2145 Set_Is_Limited_Composite (Current_Scope, False);
2149 -- If the component is an unconstrained task or protected type with
2150 -- discriminants, the component and the enclosing record are limited
2151 -- and the component is constrained by its default values. Compute
2152 -- its actual subtype, else it may be allocated the maximum size by
2153 -- the backend, and possibly overflow.
2155 if Is_Concurrent_Type (T)
2156 and then not Is_Constrained (T)
2157 and then Has_Discriminants (T)
2158 and then not Has_Discriminants (Current_Scope)
2161 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2164 Set_Etype (Id, Act_T);
2166 -- Rewrite component definition to use the constrained subtype
2168 Rewrite (Component_Definition (N),
2169 Make_Component_Definition (Loc,
2170 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2174 Set_Original_Record_Component (Id, Id);
2176 if Has_Aspects (N) then
2177 Analyze_Aspect_Specifications (N, Id);
2180 Analyze_Dimension (N);
2181 end Analyze_Component_Declaration;
2183 --------------------------
2184 -- Analyze_Declarations --
2185 --------------------------
2187 procedure Analyze_Declarations (L : List_Id) is
2190 procedure Adjust_Decl;
2191 -- Adjust Decl not to include implicit label declarations, since these
2192 -- have strange Sloc values that result in elaboration check problems.
2193 -- (They have the sloc of the label as found in the source, and that
2194 -- is ahead of the current declarative part).
2196 procedure Build_Assertion_Bodies (Decls : List_Id; Context : Node_Id);
2197 -- Create the subprogram bodies which verify the run-time semantics of
2198 -- the pragmas listed below for each elibigle type found in declarative
2199 -- list Decls. The pragmas are:
2201 -- Default_Initial_Condition
2205 -- Context denotes the owner of the declarative list.
2207 procedure Check_Entry_Contracts;
2208 -- Perform a pre-analysis of the pre- and postconditions of an entry
2209 -- declaration. This must be done before full resolution and creation
2210 -- of the parameter block, etc. to catch illegal uses within the
2211 -- contract expression. Full analysis of the expression is done when
2212 -- the contract is processed.
2214 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2215 -- Determine whether Body_Decl denotes the body of a late controlled
2216 -- primitive (either Initialize, Adjust or Finalize). If this is the
2217 -- case, add a proper spec if the body lacks one. The spec is inserted
2218 -- before Body_Decl and immediately analyzed.
2220 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id);
2221 -- Spec_Id is the entity of a package that may define abstract states,
2222 -- and in the case of a child unit, whose ancestors may define abstract
2223 -- states. If the states have partial visible refinement, remove the
2224 -- partial visibility of each constituent at the end of the package
2225 -- spec and body declarations.
2227 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2228 -- Spec_Id is the entity of a package that may define abstract states.
2229 -- If the states have visible refinement, remove the visibility of each
2230 -- constituent at the end of the package body declaration.
2232 procedure Resolve_Aspects;
2233 -- Utility to resolve the expressions of aspects at the end of a list of
2236 function Uses_Unseen_Priv (Pkg : Entity_Id) return Boolean;
2237 -- Check if a nested package has entities within it that rely on library
2238 -- level private types where the full view has not been seen for the
2239 -- purposes of checking if it is acceptable to freeze an expression
2240 -- function at the point of declaration.
2246 procedure Adjust_Decl is
2248 while Present (Prev (Decl))
2249 and then Nkind (Decl) = N_Implicit_Label_Declaration
2255 ----------------------------
2256 -- Build_Assertion_Bodies --
2257 ----------------------------
2259 procedure Build_Assertion_Bodies (Decls : List_Id; Context : Node_Id) is
2260 procedure Build_Assertion_Bodies_For_Type (Typ : Entity_Id);
2261 -- Create the subprogram bodies which verify the run-time semantics
2262 -- of the pragmas listed below for type Typ. The pragmas are:
2264 -- Default_Initial_Condition
2268 -------------------------------------
2269 -- Build_Assertion_Bodies_For_Type --
2270 -------------------------------------
2272 procedure Build_Assertion_Bodies_For_Type (Typ : Entity_Id) is
2274 -- Preanalyze and resolve the Default_Initial_Condition assertion
2275 -- expression at the end of the declarations to catch any errors.
2277 if Has_DIC (Typ) then
2278 Build_DIC_Procedure_Body (Typ);
2281 if Nkind (Context) = N_Package_Specification then
2283 -- Preanalyze and resolve the class-wide invariants of an
2284 -- interface at the end of whichever declarative part has the
2285 -- interface type. Note that an interface may be declared in
2286 -- any non-package declarative part, but reaching the end of
2287 -- such a declarative part will always freeze the type and
2288 -- generate the invariant procedure (see Freeze_Type).
2290 if Is_Interface (Typ) then
2292 -- Interfaces are treated as the partial view of a private
2293 -- type, in order to achieve uniformity with the general
2294 -- case. As a result, an interface receives only a "partial"
2295 -- invariant procedure, which is never called.
2297 if Has_Own_Invariants (Typ) then
2298 Build_Invariant_Procedure_Body
2300 Partial_Invariant => True);
2303 -- Preanalyze and resolve the invariants of a private type
2304 -- at the end of the visible declarations to catch potential
2305 -- errors. Inherited class-wide invariants are not included
2306 -- because they have already been resolved.
2308 elsif Decls = Visible_Declarations (Context)
2309 and then Ekind_In (Typ, E_Limited_Private_Type,
2311 E_Record_Type_With_Private)
2312 and then Has_Own_Invariants (Typ)
2314 Build_Invariant_Procedure_Body
2316 Partial_Invariant => True);
2318 -- Preanalyze and resolve the invariants of a private type's
2319 -- full view at the end of the private declarations to catch
2320 -- potential errors.
2322 elsif Decls = Private_Declarations (Context)
2323 and then not Is_Private_Type (Typ)
2324 and then Has_Private_Declaration (Typ)
2325 and then Has_Invariants (Typ)
2327 Build_Invariant_Procedure_Body (Typ);
2330 end Build_Assertion_Bodies_For_Type;
2335 Decl_Id : Entity_Id;
2337 -- Start of processing for Build_Assertion_Bodies
2340 Decl := First (Decls);
2341 while Present (Decl) loop
2342 if Is_Declaration (Decl) then
2343 Decl_Id := Defining_Entity (Decl);
2345 if Is_Type (Decl_Id) then
2346 Build_Assertion_Bodies_For_Type (Decl_Id);
2352 end Build_Assertion_Bodies;
2354 ---------------------------
2355 -- Check_Entry_Contracts --
2356 ---------------------------
2358 procedure Check_Entry_Contracts is
2364 Ent := First_Entity (Current_Scope);
2365 while Present (Ent) loop
2367 -- This only concerns entries with pre/postconditions
2369 if Ekind (Ent) = E_Entry
2370 and then Present (Contract (Ent))
2371 and then Present (Pre_Post_Conditions (Contract (Ent)))
2373 ASN := Pre_Post_Conditions (Contract (Ent));
2375 Install_Formals (Ent);
2377 -- Pre/postconditions are rewritten as Check pragmas. Analysis
2378 -- is performed on a copy of the pragma expression, to prevent
2379 -- modifying the original expression.
2381 while Present (ASN) loop
2382 if Nkind (ASN) = N_Pragma then
2386 (First (Pragma_Argument_Associations (ASN))));
2387 Set_Parent (Exp, ASN);
2389 Preanalyze_Assert_Expression (Exp, Standard_Boolean);
2392 ASN := Next_Pragma (ASN);
2400 end Check_Entry_Contracts;
2402 --------------------------------------
2403 -- Handle_Late_Controlled_Primitive --
2404 --------------------------------------
2406 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2407 Body_Spec : constant Node_Id := Specification (Body_Decl);
2408 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2409 Loc : constant Source_Ptr := Sloc (Body_Id);
2410 Params : constant List_Id :=
2411 Parameter_Specifications (Body_Spec);
2413 Spec_Id : Entity_Id;
2417 -- Consider only procedure bodies whose name matches one of the three
2418 -- controlled primitives.
2420 if Nkind (Body_Spec) /= N_Procedure_Specification
2421 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2427 -- A controlled primitive must have exactly one formal which is not
2428 -- an anonymous access type.
2430 elsif List_Length (Params) /= 1 then
2434 Typ := Parameter_Type (First (Params));
2436 if Nkind (Typ) = N_Access_Definition then
2442 -- The type of the formal must be derived from [Limited_]Controlled
2444 if not Is_Controlled (Entity (Typ)) then
2448 -- Check whether a specification exists for this body. We do not
2449 -- analyze the spec of the body in full, because it will be analyzed
2450 -- again when the body is properly analyzed, and we cannot create
2451 -- duplicate entries in the formals chain. We look for an explicit
2452 -- specification because the body may be an overriding operation and
2453 -- an inherited spec may be present.
2455 Spec_Id := Current_Entity (Body_Id);
2457 while Present (Spec_Id) loop
2458 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2459 and then Scope (Spec_Id) = Current_Scope
2460 and then Present (First_Formal (Spec_Id))
2461 and then No (Next_Formal (First_Formal (Spec_Id)))
2462 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2463 and then Comes_From_Source (Spec_Id)
2468 Spec_Id := Homonym (Spec_Id);
2471 -- At this point the body is known to be a late controlled primitive.
2472 -- Generate a matching spec and insert it before the body. Note the
2473 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2474 -- tree in this case.
2476 Spec := Copy_Separate_Tree (Body_Spec);
2478 -- Ensure that the subprogram declaration does not inherit the null
2479 -- indicator from the body as we now have a proper spec/body pair.
2481 Set_Null_Present (Spec, False);
2483 -- Ensure that the freeze node is inserted after the declaration of
2484 -- the primitive since its expansion will freeze the primitive.
2486 Decl := Make_Subprogram_Declaration (Loc, Specification => Spec);
2488 Insert_Before_And_Analyze (Body_Decl, Decl);
2489 end Handle_Late_Controlled_Primitive;
2491 ----------------------------------------
2492 -- Remove_Partial_Visible_Refinements --
2493 ----------------------------------------
2495 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id) is
2496 State_Elmt : Elmt_Id;
2498 if Present (Abstract_States (Spec_Id)) then
2499 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2500 while Present (State_Elmt) loop
2501 Set_Has_Partial_Visible_Refinement (Node (State_Elmt), False);
2502 Next_Elmt (State_Elmt);
2506 -- For a child unit, also hide the partial state refinement from
2507 -- ancestor packages.
2509 if Is_Child_Unit (Spec_Id) then
2510 Remove_Partial_Visible_Refinements (Scope (Spec_Id));
2512 end Remove_Partial_Visible_Refinements;
2514 --------------------------------
2515 -- Remove_Visible_Refinements --
2516 --------------------------------
2518 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2519 State_Elmt : Elmt_Id;
2521 if Present (Abstract_States (Spec_Id)) then
2522 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2523 while Present (State_Elmt) loop
2524 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2525 Next_Elmt (State_Elmt);
2528 end Remove_Visible_Refinements;
2530 ---------------------
2531 -- Resolve_Aspects --
2532 ---------------------
2534 procedure Resolve_Aspects is
2538 E := First_Entity (Current_Scope);
2539 while Present (E) loop
2540 Resolve_Aspect_Expressions (E);
2543 end Resolve_Aspects;
2545 ----------------------
2546 -- Uses_Unseen_Priv --
2547 ----------------------
2549 function Uses_Unseen_Priv (Pkg : Entity_Id) return Boolean is
2553 -- Avoid looking through scopes that do not meet the precondition of
2554 -- Pkg not being within a library unit spec.
2556 if not Is_Compilation_Unit (Pkg)
2557 and then not Is_Generic_Instance (Pkg)
2558 and then not In_Package_Body (Enclosing_Lib_Unit_Entity (Pkg))
2560 -- Loop through all entities in the current scope to identify
2561 -- an entity that depends on a private type.
2563 Curr := First_Entity (Pkg);
2565 if Nkind (Curr) in N_Entity
2566 and then Depends_On_Private (Curr)
2571 exit when Last_Entity (Current_Scope) = Curr;
2572 Curr := Next_Entity (Curr);
2577 end Uses_Unseen_Priv;
2581 Context : Node_Id := Empty;
2582 Freeze_From : Entity_Id := Empty;
2583 Next_Decl : Node_Id;
2585 Body_Seen : Boolean := False;
2586 -- Flag set when the first body [stub] is encountered
2588 -- Start of processing for Analyze_Declarations
2591 if Restriction_Check_Required (SPARK_05) then
2592 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2596 while Present (Decl) loop
2598 -- Package spec cannot contain a package declaration in SPARK
2600 if Nkind (Decl) = N_Package_Declaration
2601 and then Nkind (Parent (L)) = N_Package_Specification
2603 Check_SPARK_05_Restriction
2604 ("package specification cannot contain a package declaration",
2608 -- Complete analysis of declaration
2611 Next_Decl := Next (Decl);
2613 if No (Freeze_From) then
2614 Freeze_From := First_Entity (Current_Scope);
2617 -- At the end of a declarative part, freeze remaining entities
2618 -- declared in it. The end of the visible declarations of package
2619 -- specification is not the end of a declarative part if private
2620 -- declarations are present. The end of a package declaration is a
2621 -- freezing point only if it a library package. A task definition or
2622 -- protected type definition is not a freeze point either. Finally,
2623 -- we do not freeze entities in generic scopes, because there is no
2624 -- code generated for them and freeze nodes will be generated for
2627 -- The end of a package instantiation is not a freeze point, but
2628 -- for now we make it one, because the generic body is inserted
2629 -- (currently) immediately after. Generic instantiations will not
2630 -- be a freeze point once delayed freezing of bodies is implemented.
2631 -- (This is needed in any case for early instantiations ???).
2633 if No (Next_Decl) then
2634 if Nkind (Parent (L)) = N_Component_List then
2637 elsif Nkind_In (Parent (L), N_Protected_Definition,
2640 Check_Entry_Contracts;
2642 elsif Nkind (Parent (L)) /= N_Package_Specification then
2643 if Nkind (Parent (L)) = N_Package_Body then
2644 Freeze_From := First_Entity (Current_Scope);
2647 -- There may have been several freezing points previously,
2648 -- for example object declarations or subprogram bodies, but
2649 -- at the end of a declarative part we check freezing from
2650 -- the beginning, even though entities may already be frozen,
2651 -- in order to perform visibility checks on delayed aspects.
2655 -- If the current scope is a generic subprogram body. Skip the
2656 -- generic formal parameters that are not frozen here.
2658 if Is_Subprogram (Current_Scope)
2659 and then Nkind (Unit_Declaration_Node (Current_Scope)) =
2660 N_Generic_Subprogram_Declaration
2661 and then Present (First_Entity (Current_Scope))
2663 while Is_Generic_Formal (Freeze_From) loop
2664 Freeze_From := Next_Entity (Freeze_From);
2667 Freeze_All (Freeze_From, Decl);
2668 Freeze_From := Last_Entity (Current_Scope);
2671 -- For declarations in a subprogram body there is no issue
2672 -- with name resolution in aspect specifications, but in
2673 -- ASIS mode we need to preanalyze aspect specifications
2674 -- that may otherwise only be analyzed during expansion
2675 -- (e.g. during generation of a related subprogram).
2681 Freeze_All (First_Entity (Current_Scope), Decl);
2682 Freeze_From := Last_Entity (Current_Scope);
2685 -- Current scope is a package specification
2687 elsif Scope (Current_Scope) /= Standard_Standard
2688 and then not Is_Child_Unit (Current_Scope)
2689 and then No (Generic_Parent (Parent (L)))
2691 -- ARM rule 13.1.1(11/3): usage names in aspect definitions are
2692 -- resolved at the end of the immediately enclosing declaration
2693 -- list (AI05-0183-1).
2697 elsif L /= Visible_Declarations (Parent (L))
2698 or else No (Private_Declarations (Parent (L)))
2699 or else Is_Empty_List (Private_Declarations (Parent (L)))
2703 -- End of a package declaration
2705 -- In compilation mode the expansion of freeze node takes care
2706 -- of resolving expressions of all aspects in the list. In ASIS
2707 -- mode this must be done explicitly.
2710 and then Scope (Current_Scope) = Standard_Standard
2715 -- This is a freeze point because it is the end of a
2716 -- compilation unit.
2718 Freeze_All (First_Entity (Current_Scope), Decl);
2719 Freeze_From := Last_Entity (Current_Scope);
2721 -- At the end of the visible declarations the expressions in
2722 -- aspects of all entities declared so far must be resolved.
2723 -- The entities themselves might be frozen later, and the
2724 -- generated pragmas and attribute definition clauses analyzed
2725 -- in full at that point, but name resolution must take place
2727 -- In addition to being the proper semantics, this is mandatory
2728 -- within generic units, because global name capture requires
2729 -- those expressions to be analyzed, given that the generated
2730 -- pragmas do not appear in the original generic tree.
2732 elsif Serious_Errors_Detected = 0 then
2736 -- If next node is a body then freeze all types before the body.
2737 -- An exception occurs for some expander-generated bodies. If these
2738 -- are generated at places where in general language rules would not
2739 -- allow a freeze point, then we assume that the expander has
2740 -- explicitly checked that all required types are properly frozen,
2741 -- and we do not cause general freezing here. This special circuit
2742 -- is used when the encountered body is marked as having already
2745 -- In all other cases (bodies that come from source, and expander
2746 -- generated bodies that have not been analyzed yet), freeze all
2747 -- types now. Note that in the latter case, the expander must take
2748 -- care to attach the bodies at a proper place in the tree so as to
2749 -- not cause unwanted freezing at that point.
2751 -- It is also necessary to check for a case where both an expression
2752 -- function is used and the current scope depends on an unseen
2753 -- private type from a library unit, otherwise premature freezing of
2754 -- the private type will occur.
2756 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl)
2757 and then ((Nkind (Next_Decl) /= N_Subprogram_Body
2758 or else not Was_Expression_Function (Next_Decl))
2759 or else (not Is_Ignored_Ghost_Entity (Current_Scope)
2760 and then not Uses_Unseen_Priv (Current_Scope)))
2762 -- When a controlled type is frozen, the expander generates stream
2763 -- and controlled-type support routines. If the freeze is caused
2764 -- by the stand-alone body of Initialize, Adjust, or Finalize, the
2765 -- expander will end up using the wrong version of these routines,
2766 -- as the body has not been processed yet. To remedy this, detect
2767 -- a late controlled primitive and create a proper spec for it.
2768 -- This ensures that the primitive will override its inherited
2769 -- counterpart before the freeze takes place.
2771 -- If the declaration we just processed is a body, do not attempt
2772 -- to examine Next_Decl as the late primitive idiom can only apply
2773 -- to the first encountered body.
2775 -- The spec of the late primitive is not generated in ASIS mode to
2776 -- ensure a consistent list of primitives that indicates the true
2777 -- semantic structure of the program (which is not relevant when
2778 -- generating executable code).
2780 -- ??? A cleaner approach may be possible and/or this solution
2781 -- could be extended to general-purpose late primitives, TBD.
2784 and then not Body_Seen
2785 and then not Is_Body (Decl)
2789 if Nkind (Next_Decl) = N_Subprogram_Body then
2790 Handle_Late_Controlled_Primitive (Next_Decl);
2796 -- The generated body of an expression function does not freeze,
2797 -- unless it is a completion, in which case only the expression
2798 -- itself freezes. This is handled when the body itself is
2799 -- analyzed (see Freeze_Expr_Types, sem_ch6.adb).
2801 Freeze_All (Freeze_From, Decl);
2802 Freeze_From := Last_Entity (Current_Scope);
2808 -- Post-freezing actions
2811 Context := Parent (L);
2813 -- Analyze the contracts of packages and their bodies
2815 if Nkind (Context) = N_Package_Specification then
2817 -- When a package has private declarations, its contract must be
2818 -- analyzed at the end of the said declarations. This way both the
2819 -- analysis and freeze actions are properly synchronized in case
2820 -- of private type use within the contract.
2822 if L = Private_Declarations (Context) then
2823 Analyze_Package_Contract (Defining_Entity (Context));
2825 -- Otherwise the contract is analyzed at the end of the visible
2828 elsif L = Visible_Declarations (Context)
2829 and then No (Private_Declarations (Context))
2831 Analyze_Package_Contract (Defining_Entity (Context));
2834 elsif Nkind (Context) = N_Package_Body then
2835 Analyze_Package_Body_Contract (Defining_Entity (Context));
2838 -- Analyze the contracts of various constructs now due to the delayed
2839 -- visibility needs of their aspects and pragmas.
2841 Analyze_Contracts (L);
2843 if Nkind (Context) = N_Package_Body then
2845 -- Ensure that all abstract states and objects declared in the
2846 -- state space of a package body are utilized as constituents.
2848 Check_Unused_Body_States (Defining_Entity (Context));
2850 -- State refinements are visible up to the end of the package body
2851 -- declarations. Hide the state refinements from visibility to
2852 -- restore the original state conditions.
2854 Remove_Visible_Refinements (Corresponding_Spec (Context));
2855 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2857 elsif Nkind (Context) = N_Package_Declaration then
2859 -- Partial state refinements are visible up to the end of the
2860 -- package spec declarations. Hide the partial state refinements
2861 -- from visibility to restore the original state conditions.
2863 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2866 -- Verify that all abstract states found in any package declared in
2867 -- the input declarative list have proper refinements. The check is
2868 -- performed only when the context denotes a block, entry, package,
2869 -- protected, subprogram, or task body (SPARK RM 7.2.2(3)).
2871 Check_State_Refinements (Context);
2873 -- Create the subprogram bodies which verify the run-time semantics
2874 -- of pragmas Default_Initial_Condition and [Type_]Invariant for all
2875 -- types within the current declarative list. This ensures that all
2876 -- assertion expressions are preanalyzed and resolved at the end of
2877 -- the declarative part. Note that the resolution happens even when
2878 -- freezing does not take place.
2880 Build_Assertion_Bodies (L, Context);
2882 end Analyze_Declarations;
2884 -----------------------------------
2885 -- Analyze_Full_Type_Declaration --
2886 -----------------------------------
2888 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2889 Def : constant Node_Id := Type_Definition (N);
2890 Def_Id : constant Entity_Id := Defining_Identifier (N);
2894 Is_Remote : constant Boolean :=
2895 (Is_Remote_Types (Current_Scope)
2896 or else Is_Remote_Call_Interface (Current_Scope))
2897 and then not (In_Private_Part (Current_Scope)
2898 or else In_Package_Body (Current_Scope));
2900 procedure Check_Nonoverridable_Aspects;
2901 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2902 -- be overridden, and can only be confirmed on derivation.
2904 procedure Check_Ops_From_Incomplete_Type;
2905 -- If there is a tagged incomplete partial view of the type, traverse
2906 -- the primitives of the incomplete view and change the type of any
2907 -- controlling formals and result to indicate the full view. The
2908 -- primitives will be added to the full type's primitive operations
2909 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2910 -- is called from Process_Incomplete_Dependents).
2912 ----------------------------------
2913 -- Check_Nonoverridable_Aspects --
2914 ----------------------------------
2916 procedure Check_Nonoverridable_Aspects is
2917 function Get_Aspect_Spec
2919 Aspect_Name : Name_Id) return Node_Id;
2920 -- Check whether a list of aspect specifications includes an entry
2921 -- for a specific aspect. The list is either that of a partial or
2924 ---------------------
2925 -- Get_Aspect_Spec --
2926 ---------------------
2928 function Get_Aspect_Spec
2930 Aspect_Name : Name_Id) return Node_Id
2935 Spec := First (Specs);
2936 while Present (Spec) loop
2937 if Chars (Identifier (Spec)) = Aspect_Name then
2944 end Get_Aspect_Spec;
2948 Prev_Aspects : constant List_Id :=
2949 Aspect_Specifications (Parent (Def_Id));
2950 Par_Type : Entity_Id;
2951 Prev_Aspect : Node_Id;
2953 -- Start of processing for Check_Nonoverridable_Aspects
2956 -- Get parent type of derived type. Note that Prev is the entity in
2957 -- the partial declaration, but its contents are now those of full
2958 -- view, while Def_Id reflects the partial view.
2960 if Is_Private_Type (Def_Id) then
2961 Par_Type := Etype (Full_View (Def_Id));
2963 Par_Type := Etype (Def_Id);
2966 -- If there is an inherited Implicit_Dereference, verify that it is
2967 -- made explicit in the partial view.
2969 if Has_Discriminants (Base_Type (Par_Type))
2970 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2971 and then Present (Discriminant_Specifications (Parent (Prev)))
2972 and then Present (Get_Reference_Discriminant (Par_Type))
2975 Get_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference);
2979 (Discriminant_Specifications
2980 (Original_Node (Parent (Prev))))
2983 ("type does not inherit implicit dereference", Prev);
2986 -- If one of the views has the aspect specified, verify that it
2987 -- is consistent with that of the parent.
2990 Par_Discr : constant Entity_Id :=
2991 Get_Reference_Discriminant (Par_Type);
2992 Cur_Discr : constant Entity_Id :=
2993 Get_Reference_Discriminant (Prev);
2996 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2997 Error_Msg_N ("aspect incosistent with that of parent", N);
3000 -- Check that specification in partial view matches the
3001 -- inherited aspect. Compare names directly because aspect
3002 -- expression may not be analyzed.
3004 if Present (Prev_Aspect)
3005 and then Nkind (Expression (Prev_Aspect)) = N_Identifier
3006 and then Chars (Expression (Prev_Aspect)) /=
3010 ("aspect incosistent with that of parent", N);
3016 -- TBD : other nonoverridable aspects.
3017 end Check_Nonoverridable_Aspects;
3019 ------------------------------------
3020 -- Check_Ops_From_Incomplete_Type --
3021 ------------------------------------
3023 procedure Check_Ops_From_Incomplete_Type is
3030 and then Ekind (Prev) = E_Incomplete_Type
3031 and then Is_Tagged_Type (Prev)
3032 and then Is_Tagged_Type (T)
3034 Elmt := First_Elmt (Primitive_Operations (Prev));
3035 while Present (Elmt) loop
3038 Formal := First_Formal (Op);
3039 while Present (Formal) loop
3040 if Etype (Formal) = Prev then
3041 Set_Etype (Formal, T);
3044 Next_Formal (Formal);
3047 if Etype (Op) = Prev then
3054 end Check_Ops_From_Incomplete_Type;
3056 -- Start of processing for Analyze_Full_Type_Declaration
3059 Prev := Find_Type_Name (N);
3061 -- The full view, if present, now points to the current type. If there
3062 -- is an incomplete partial view, set a link to it, to simplify the
3063 -- retrieval of primitive operations of the type.
3065 -- Ada 2005 (AI-50217): If the type was previously decorated when
3066 -- imported through a LIMITED WITH clause, it appears as incomplete
3067 -- but has no full view.
3069 if Ekind (Prev) = E_Incomplete_Type
3070 and then Present (Full_View (Prev))
3072 T := Full_View (Prev);
3073 Set_Incomplete_View (N, Parent (Prev));
3078 Set_Is_Pure (T, Is_Pure (Current_Scope));
3080 -- We set the flag Is_First_Subtype here. It is needed to set the
3081 -- corresponding flag for the Implicit class-wide-type created
3082 -- during tagged types processing.
3084 Set_Is_First_Subtype (T, True);
3086 -- Only composite types other than array types are allowed to have
3091 -- For derived types, the rule will be checked once we've figured
3092 -- out the parent type.
3094 when N_Derived_Type_Definition =>
3097 -- For record types, discriminants are allowed, unless we are in
3100 when N_Record_Definition =>
3101 if Present (Discriminant_Specifications (N)) then
3102 Check_SPARK_05_Restriction
3103 ("discriminant type is not allowed",
3105 (First (Discriminant_Specifications (N))));
3109 if Present (Discriminant_Specifications (N)) then
3111 ("elementary or array type cannot have discriminants",
3113 (First (Discriminant_Specifications (N))));
3117 -- Elaborate the type definition according to kind, and generate
3118 -- subsidiary (implicit) subtypes where needed. We skip this if it was
3119 -- already done (this happens during the reanalysis that follows a call
3120 -- to the high level optimizer).
3122 if not Analyzed (T) then
3126 when N_Access_To_Subprogram_Definition =>
3127 Access_Subprogram_Declaration (T, Def);
3129 -- If this is a remote access to subprogram, we must create the
3130 -- equivalent fat pointer type, and related subprograms.
3133 Process_Remote_AST_Declaration (N);
3136 -- Validate categorization rule against access type declaration
3137 -- usually a violation in Pure unit, Shared_Passive unit.
3139 Validate_Access_Type_Declaration (T, N);
3141 when N_Access_To_Object_Definition =>
3142 Access_Type_Declaration (T, Def);
3144 -- Validate categorization rule against access type declaration
3145 -- usually a violation in Pure unit, Shared_Passive unit.
3147 Validate_Access_Type_Declaration (T, N);
3149 -- If we are in a Remote_Call_Interface package and define a
3150 -- RACW, then calling stubs and specific stream attributes
3154 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
3156 Add_RACW_Features (Def_Id);
3159 when N_Array_Type_Definition =>
3160 Array_Type_Declaration (T, Def);
3162 when N_Derived_Type_Definition =>
3163 Derived_Type_Declaration (T, N, T /= Def_Id);
3165 -- Inherit predicates from parent, and protect against illegal
3168 if Is_Type (T) and then Has_Predicates (T) then
3169 Set_Has_Predicates (Def_Id);
3172 when N_Enumeration_Type_Definition =>
3173 Enumeration_Type_Declaration (T, Def);
3175 when N_Floating_Point_Definition =>
3176 Floating_Point_Type_Declaration (T, Def);
3178 when N_Decimal_Fixed_Point_Definition =>
3179 Decimal_Fixed_Point_Type_Declaration (T, Def);
3181 when N_Ordinary_Fixed_Point_Definition =>
3182 Ordinary_Fixed_Point_Type_Declaration (T, Def);
3184 when N_Signed_Integer_Type_Definition =>
3185 Signed_Integer_Type_Declaration (T, Def);
3187 when N_Modular_Type_Definition =>
3188 Modular_Type_Declaration (T, Def);
3190 when N_Record_Definition =>
3191 Record_Type_Declaration (T, N, Prev);
3193 -- If declaration has a parse error, nothing to elaborate.
3199 raise Program_Error;
3203 if Etype (T) = Any_Type then
3207 -- Controlled type is not allowed in SPARK
3209 if Is_Visibly_Controlled (T) then
3210 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
3213 -- Some common processing for all types
3215 Set_Depends_On_Private (T, Has_Private_Component (T));
3216 Check_Ops_From_Incomplete_Type;
3218 -- Both the declared entity, and its anonymous base type if one was
3219 -- created, need freeze nodes allocated.
3222 B : constant Entity_Id := Base_Type (T);
3225 -- In the case where the base type differs from the first subtype, we
3226 -- pre-allocate a freeze node, and set the proper link to the first
3227 -- subtype. Freeze_Entity will use this preallocated freeze node when
3228 -- it freezes the entity.
3230 -- This does not apply if the base type is a generic type, whose
3231 -- declaration is independent of the current derived definition.
3233 if B /= T and then not Is_Generic_Type (B) then
3234 Ensure_Freeze_Node (B);
3235 Set_First_Subtype_Link (Freeze_Node (B), T);
3238 -- A type that is imported through a limited_with clause cannot
3239 -- generate any code, and thus need not be frozen. However, an access
3240 -- type with an imported designated type needs a finalization list,
3241 -- which may be referenced in some other package that has non-limited
3242 -- visibility on the designated type. Thus we must create the
3243 -- finalization list at the point the access type is frozen, to
3244 -- prevent unsatisfied references at link time.
3246 if not From_Limited_With (T) or else Is_Access_Type (T) then
3247 Set_Has_Delayed_Freeze (T);
3251 -- Case where T is the full declaration of some private type which has
3252 -- been swapped in Defining_Identifier (N).
3254 if T /= Def_Id and then Is_Private_Type (Def_Id) then
3255 Process_Full_View (N, T, Def_Id);
3257 -- Record the reference. The form of this is a little strange, since
3258 -- the full declaration has been swapped in. So the first parameter
3259 -- here represents the entity to which a reference is made which is
3260 -- the "real" entity, i.e. the one swapped in, and the second
3261 -- parameter provides the reference location.
3263 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
3264 -- since we don't want a complaint about the full type being an
3265 -- unwanted reference to the private type
3268 B : constant Boolean := Has_Pragma_Unreferenced (T);
3270 Set_Has_Pragma_Unreferenced (T, False);
3271 Generate_Reference (T, T, 'c');
3272 Set_Has_Pragma_Unreferenced (T, B);
3275 Set_Completion_Referenced (Def_Id);
3277 -- For completion of incomplete type, process incomplete dependents
3278 -- and always mark the full type as referenced (it is the incomplete
3279 -- type that we get for any real reference).
3281 elsif Ekind (Prev) = E_Incomplete_Type then
3282 Process_Incomplete_Dependents (N, T, Prev);
3283 Generate_Reference (Prev, Def_Id, 'c');
3284 Set_Completion_Referenced (Def_Id);
3286 -- If not private type or incomplete type completion, this is a real
3287 -- definition of a new entity, so record it.
3290 Generate_Definition (Def_Id);
3293 -- Propagate any pending access types whose finalization masters need to
3294 -- be fully initialized from the partial to the full view. Guard against
3295 -- an illegal full view that remains unanalyzed.
3297 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
3298 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
3301 if Chars (Scope (Def_Id)) = Name_System
3302 and then Chars (Def_Id) = Name_Address
3303 and then In_Predefined_Unit (N)
3305 Set_Is_Descendant_Of_Address (Def_Id);
3306 Set_Is_Descendant_Of_Address (Base_Type (Def_Id));
3307 Set_Is_Descendant_Of_Address (Prev);
3310 Set_Optimize_Alignment_Flags (Def_Id);
3311 Check_Eliminated (Def_Id);
3313 -- If the declaration is a completion and aspects are present, apply
3314 -- them to the entity for the type which is currently the partial
3315 -- view, but which is the one that will be frozen.
3317 if Has_Aspects (N) then
3319 -- In most cases the partial view is a private type, and both views
3320 -- appear in different declarative parts. In the unusual case where
3321 -- the partial view is incomplete, perform the analysis on the
3322 -- full view, to prevent freezing anomalies with the corresponding
3323 -- class-wide type, which otherwise might be frozen before the
3324 -- dispatch table is built.
3327 and then Ekind (Prev) /= E_Incomplete_Type
3329 Analyze_Aspect_Specifications (N, Prev);
3334 Analyze_Aspect_Specifications (N, Def_Id);
3338 if Is_Derived_Type (Prev)
3339 and then Def_Id /= Prev
3341 Check_Nonoverridable_Aspects;
3343 end Analyze_Full_Type_Declaration;
3345 ----------------------------------
3346 -- Analyze_Incomplete_Type_Decl --
3347 ----------------------------------
3349 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3350 F : constant Boolean := Is_Pure (Current_Scope);
3354 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3356 Generate_Definition (Defining_Identifier (N));
3358 -- Process an incomplete declaration. The identifier must not have been
3359 -- declared already in the scope. However, an incomplete declaration may
3360 -- appear in the private part of a package, for a private type that has
3361 -- already been declared.
3363 -- In this case, the discriminants (if any) must match
3365 T := Find_Type_Name (N);
3367 Set_Ekind (T, E_Incomplete_Type);
3368 Init_Size_Align (T);
3369 Set_Is_First_Subtype (T, True);
3372 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3373 -- incomplete types.
3375 if Tagged_Present (N) then
3376 Set_Is_Tagged_Type (T, True);
3377 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3378 Make_Class_Wide_Type (T);
3379 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3382 Set_Stored_Constraint (T, No_Elist);
3384 if Present (Discriminant_Specifications (N)) then
3386 Process_Discriminants (N);
3390 -- If the type has discriminants, nontrivial subtypes may be declared
3391 -- before the full view of the type. The full views of those subtypes
3392 -- will be built after the full view of the type.
3394 Set_Private_Dependents (T, New_Elmt_List);
3396 end Analyze_Incomplete_Type_Decl;
3398 -----------------------------------
3399 -- Analyze_Interface_Declaration --
3400 -----------------------------------
3402 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3403 CW : constant Entity_Id := Class_Wide_Type (T);
3406 Set_Is_Tagged_Type (T);
3407 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3409 Set_Is_Limited_Record (T, Limited_Present (Def)
3410 or else Task_Present (Def)
3411 or else Protected_Present (Def)
3412 or else Synchronized_Present (Def));
3414 -- Type is abstract if full declaration carries keyword, or if previous
3415 -- partial view did.
3417 Set_Is_Abstract_Type (T);
3418 Set_Is_Interface (T);
3420 -- Type is a limited interface if it includes the keyword limited, task,
3421 -- protected, or synchronized.
3423 Set_Is_Limited_Interface
3424 (T, Limited_Present (Def)
3425 or else Protected_Present (Def)
3426 or else Synchronized_Present (Def)
3427 or else Task_Present (Def));
3429 Set_Interfaces (T, New_Elmt_List);
3430 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3432 -- Complete the decoration of the class-wide entity if it was already
3433 -- built (i.e. during the creation of the limited view)
3435 if Present (CW) then
3436 Set_Is_Interface (CW);
3437 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3440 -- Check runtime support for synchronized interfaces
3442 if (Is_Task_Interface (T)
3443 or else Is_Protected_Interface (T)
3444 or else Is_Synchronized_Interface (T))
3445 and then not RTE_Available (RE_Select_Specific_Data)
3447 Error_Msg_CRT ("synchronized interfaces", T);
3449 end Analyze_Interface_Declaration;
3451 -----------------------------
3452 -- Analyze_Itype_Reference --
3453 -----------------------------
3455 -- Nothing to do. This node is placed in the tree only for the benefit of
3456 -- back end processing, and has no effect on the semantic processing.
3458 procedure Analyze_Itype_Reference (N : Node_Id) is
3460 pragma Assert (Is_Itype (Itype (N)));
3462 end Analyze_Itype_Reference;
3464 --------------------------------
3465 -- Analyze_Number_Declaration --
3466 --------------------------------
3468 procedure Analyze_Number_Declaration (N : Node_Id) is
3469 E : constant Node_Id := Expression (N);
3470 Id : constant Entity_Id := Defining_Identifier (N);
3471 Index : Interp_Index;
3476 Generate_Definition (Id);
3479 -- This is an optimization of a common case of an integer literal
3481 if Nkind (E) = N_Integer_Literal then
3482 Set_Is_Static_Expression (E, True);
3483 Set_Etype (E, Universal_Integer);
3485 Set_Etype (Id, Universal_Integer);
3486 Set_Ekind (Id, E_Named_Integer);
3487 Set_Is_Frozen (Id, True);
3491 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3493 -- Process expression, replacing error by integer zero, to avoid
3494 -- cascaded errors or aborts further along in the processing
3496 -- Replace Error by integer zero, which seems least likely to cause
3500 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3501 Set_Error_Posted (E);
3506 -- Verify that the expression is static and numeric. If
3507 -- the expression is overloaded, we apply the preference
3508 -- rule that favors root numeric types.
3510 if not Is_Overloaded (E) then
3512 if Has_Dynamic_Predicate_Aspect (T) then
3514 ("subtype has dynamic predicate, "
3515 & "not allowed in number declaration", N);
3521 Get_First_Interp (E, Index, It);
3522 while Present (It.Typ) loop
3523 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3524 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3526 if T = Any_Type then
3529 elsif It.Typ = Universal_Real
3531 It.Typ = Universal_Integer
3533 -- Choose universal interpretation over any other
3540 Get_Next_Interp (Index, It);
3544 if Is_Integer_Type (T) then
3546 Set_Etype (Id, Universal_Integer);
3547 Set_Ekind (Id, E_Named_Integer);
3549 elsif Is_Real_Type (T) then
3551 -- Because the real value is converted to universal_real, this is a
3552 -- legal context for a universal fixed expression.
3554 if T = Universal_Fixed then
3556 Loc : constant Source_Ptr := Sloc (N);
3557 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3559 New_Occurrence_Of (Universal_Real, Loc),
3560 Expression => Relocate_Node (E));
3567 elsif T = Any_Fixed then
3568 Error_Msg_N ("illegal context for mixed mode operation", E);
3570 -- Expression is of the form : universal_fixed * integer. Try to
3571 -- resolve as universal_real.
3573 T := Universal_Real;
3578 Set_Etype (Id, Universal_Real);
3579 Set_Ekind (Id, E_Named_Real);
3582 Wrong_Type (E, Any_Numeric);
3586 Set_Ekind (Id, E_Constant);
3587 Set_Never_Set_In_Source (Id, True);
3588 Set_Is_True_Constant (Id, True);
3592 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3593 Set_Etype (E, Etype (Id));
3596 if not Is_OK_Static_Expression (E) then
3597 Flag_Non_Static_Expr
3598 ("non-static expression used in number declaration!", E);
3599 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3600 Set_Etype (E, Any_Type);
3603 Analyze_Dimension (N);
3604 end Analyze_Number_Declaration;
3606 --------------------------------
3607 -- Analyze_Object_Declaration --
3608 --------------------------------
3610 -- WARNING: This routine manages Ghost regions. Return statements must be
3611 -- replaced by gotos which jump to the end of the routine and restore the
3614 procedure Analyze_Object_Declaration (N : Node_Id) is
3615 Loc : constant Source_Ptr := Sloc (N);
3616 Id : constant Entity_Id := Defining_Identifier (N);
3620 E : Node_Id := Expression (N);
3621 -- E is set to Expression (N) throughout this routine. When Expression
3622 -- (N) is modified, E is changed accordingly.
3624 Prev_Entity : Entity_Id := Empty;
3626 procedure Check_Dynamic_Object (Typ : Entity_Id);
3627 -- A library-level object with non-static discriminant constraints may
3628 -- require dynamic allocation. The declaration is illegal if the
3629 -- profile includes the restriction No_Implicit_Heap_Allocations.
3631 procedure Check_For_Null_Excluding_Components
3632 (Obj_Typ : Entity_Id;
3633 Obj_Decl : Node_Id);
3634 -- Verify that each null-excluding component of object declaration
3635 -- Obj_Decl carrying type Obj_Typ has explicit initialization. Emit
3636 -- a compile-time warning if this is not the case.
3638 function Count_Tasks (T : Entity_Id) return Uint;
3639 -- This function is called when a non-generic library level object of a
3640 -- task type is declared. Its function is to count the static number of
3641 -- tasks declared within the type (it is only called if Has_Task is set
3642 -- for T). As a side effect, if an array of tasks with non-static bounds
3643 -- or a variant record type is encountered, Check_Restriction is called
3644 -- indicating the count is unknown.
3646 function Delayed_Aspect_Present return Boolean;
3647 -- If the declaration has an expression that is an aggregate, and it
3648 -- has aspects that require delayed analysis, the resolution of the
3649 -- aggregate must be deferred to the freeze point of the objet. This
3650 -- special processing was created for address clauses, but it must
3651 -- also apply to Alignment. This must be done before the aspect
3652 -- specifications are analyzed because we must handle the aggregate
3653 -- before the analysis of the object declaration is complete.
3655 -- Any other relevant delayed aspects on object declarations ???
3657 --------------------------
3658 -- Check_Dynamic_Object --
3659 --------------------------
3661 procedure Check_Dynamic_Object (Typ : Entity_Id) is
3663 Obj_Type : Entity_Id;
3668 if Is_Private_Type (Obj_Type)
3669 and then Present (Full_View (Obj_Type))
3671 Obj_Type := Full_View (Obj_Type);
3674 if Known_Static_Esize (Obj_Type) then
3678 if Restriction_Active (No_Implicit_Heap_Allocations)
3679 and then Expander_Active
3680 and then Has_Discriminants (Obj_Type)
3682 Comp := First_Component (Obj_Type);
3683 while Present (Comp) loop
3684 if Known_Static_Esize (Etype (Comp))
3685 or else Size_Known_At_Compile_Time (Etype (Comp))
3689 elsif not Discriminated_Size (Comp)
3690 and then Comes_From_Source (Comp)
3693 ("component& of non-static size will violate restriction "
3694 & "No_Implicit_Heap_Allocation?", N, Comp);
3696 elsif Is_Record_Type (Etype (Comp)) then
3697 Check_Dynamic_Object (Etype (Comp));
3700 Next_Component (Comp);
3703 end Check_Dynamic_Object;
3705 -----------------------------------------
3706 -- Check_For_Null_Excluding_Components --
3707 -----------------------------------------
3709 procedure Check_For_Null_Excluding_Components
3710 (Obj_Typ : Entity_Id;
3713 procedure Check_Component
3714 (Comp_Typ : Entity_Id;
3715 Comp_Decl : Node_Id := Empty;
3716 Array_Comp : Boolean := False);
3717 -- Apply a compile-time null-exclusion check on a component denoted
3718 -- by its declaration Comp_Decl and type Comp_Typ, and all of its
3719 -- subcomponents (if any).
3721 ---------------------
3722 -- Check_Component --
3723 ---------------------
3725 procedure Check_Component
3726 (Comp_Typ : Entity_Id;
3727 Comp_Decl : Node_Id := Empty;
3728 Array_Comp : Boolean := False)
3734 -- Do not consider internally-generated components or those that
3735 -- are already initialized.
3737 if Present (Comp_Decl)
3738 and then (not Comes_From_Source (Comp_Decl)
3739 or else Present (Expression (Comp_Decl)))
3744 if Is_Incomplete_Or_Private_Type (Comp_Typ)
3745 and then Present (Full_View (Comp_Typ))
3747 T := Full_View (Comp_Typ);
3752 -- Verify a component of a null-excluding access type
3754 if Is_Access_Type (T)
3755 and then Can_Never_Be_Null (T)
3757 if Comp_Decl = Obj_Decl then
3758 Null_Exclusion_Static_Checks
3761 Array_Comp => Array_Comp);
3764 Null_Exclusion_Static_Checks
3767 Array_Comp => Array_Comp);
3770 -- Check array components
3772 elsif Is_Array_Type (T) then
3774 -- There is no suitable component when the object is of an
3775 -- array type. However, a namable component may appear at some
3776 -- point during the recursive inspection, but not at the top
3777 -- level. At the top level just indicate array component case.
3779 if Comp_Decl = Obj_Decl then
3780 Check_Component (Component_Type (T), Array_Comp => True);
3782 Check_Component (Component_Type (T), Comp_Decl);
3785 -- Verify all components of type T
3787 -- Note: No checks are performed on types with discriminants due
3788 -- to complexities involving variants. ???
3790 elsif (Is_Concurrent_Type (T)
3791 or else Is_Incomplete_Or_Private_Type (T)
3792 or else Is_Record_Type (T))
3793 and then not Has_Discriminants (T)
3795 Comp := First_Component (T);
3796 while Present (Comp) loop
3797 Check_Component (Etype (Comp), Parent (Comp));
3799 Comp := Next_Component (Comp);
3802 end Check_Component;
3804 -- Start processing for Check_For_Null_Excluding_Components
3807 Check_Component (Obj_Typ, Obj_Decl);
3808 end Check_For_Null_Excluding_Components;
3814 function Count_Tasks (T : Entity_Id) return Uint is
3820 if Is_Task_Type (T) then
3823 elsif Is_Record_Type (T) then
3824 if Has_Discriminants (T) then
3825 Check_Restriction (Max_Tasks, N);
3830 C := First_Component (T);
3831 while Present (C) loop
3832 V := V + Count_Tasks (Etype (C));
3839 elsif Is_Array_Type (T) then
3840 X := First_Index (T);
3841 V := Count_Tasks (Component_Type (T));
3842 while Present (X) loop
3845 if not Is_OK_Static_Subtype (C) then
3846 Check_Restriction (Max_Tasks, N);
3849 V := V * (UI_Max (Uint_0,
3850 Expr_Value (Type_High_Bound (C)) -
3851 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3864 ----------------------------
3865 -- Delayed_Aspect_Present --
3866 ----------------------------
3868 function Delayed_Aspect_Present return Boolean is
3873 if Present (Aspect_Specifications (N)) then
3874 A := First (Aspect_Specifications (N));
3875 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3876 while Present (A) loop
3877 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3886 end Delayed_Aspect_Present;
3890 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3891 -- Save the Ghost mode to restore on exit
3893 Related_Id : Entity_Id;
3895 -- Start of processing for Analyze_Object_Declaration
3898 -- There are three kinds of implicit types generated by an
3899 -- object declaration:
3901 -- 1. Those generated by the original Object Definition
3903 -- 2. Those generated by the Expression
3905 -- 3. Those used to constrain the Object Definition with the
3906 -- expression constraints when the definition is unconstrained.
3908 -- They must be generated in this order to avoid order of elaboration
3909 -- issues. Thus the first step (after entering the name) is to analyze
3910 -- the object definition.
3912 if Constant_Present (N) then
3913 Prev_Entity := Current_Entity_In_Scope (Id);
3915 if Present (Prev_Entity)
3917 -- If the homograph is an implicit subprogram, it is overridden
3918 -- by the current declaration.
3920 ((Is_Overloadable (Prev_Entity)
3921 and then Is_Inherited_Operation (Prev_Entity))
3923 -- The current object is a discriminal generated for an entry
3924 -- family index. Even though the index is a constant, in this
3925 -- particular context there is no true constant redeclaration.
3926 -- Enter_Name will handle the visibility.
3929 (Is_Discriminal (Id)
3930 and then Ekind (Discriminal_Link (Id)) =
3931 E_Entry_Index_Parameter)
3933 -- The current object is the renaming for a generic declared
3934 -- within the instance.
3937 (Ekind (Prev_Entity) = E_Package
3938 and then Nkind (Parent (Prev_Entity)) =
3939 N_Package_Renaming_Declaration
3940 and then not Comes_From_Source (Prev_Entity)
3942 Is_Generic_Instance (Renamed_Entity (Prev_Entity)))
3944 -- The entity may be a homonym of a private component of the
3945 -- enclosing protected object, for which we create a local
3946 -- renaming declaration. The declaration is legal, even if
3947 -- useless when it just captures that component.
3950 (Ekind (Scope (Current_Scope)) = E_Protected_Type
3951 and then Nkind (Parent (Prev_Entity)) =
3952 N_Object_Renaming_Declaration))
3954 Prev_Entity := Empty;
3958 if Present (Prev_Entity) then
3960 -- The object declaration is Ghost when it completes a deferred Ghost
3963 Mark_And_Set_Ghost_Completion (N, Prev_Entity);
3965 Constant_Redeclaration (Id, N, T);
3967 Generate_Reference (Prev_Entity, Id, 'c');
3968 Set_Completion_Referenced (Id);
3970 if Error_Posted (N) then
3972 -- Type mismatch or illegal redeclaration; do not analyze
3973 -- expression to avoid cascaded errors.
3975 T := Find_Type_Of_Object (Object_Definition (N), N);
3977 Set_Ekind (Id, E_Variable);
3981 -- In the normal case, enter identifier at the start to catch premature
3982 -- usage in the initialization expression.
3985 Generate_Definition (Id);
3988 Mark_Coextensions (N, Object_Definition (N));
3990 T := Find_Type_Of_Object (Object_Definition (N), N);
3992 if Nkind (Object_Definition (N)) = N_Access_Definition
3994 (Access_To_Subprogram_Definition (Object_Definition (N)))
3995 and then Protected_Present
3996 (Access_To_Subprogram_Definition (Object_Definition (N)))
3998 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
4001 if Error_Posted (Id) then
4003 Set_Ekind (Id, E_Variable);
4008 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
4009 -- out some static checks.
4011 if Ada_Version >= Ada_2005 then
4013 -- In case of aggregates we must also take care of the correct
4014 -- initialization of nested aggregates bug this is done at the
4015 -- point of the analysis of the aggregate (see sem_aggr.adb) ???
4017 if Can_Never_Be_Null (T) then
4018 if Present (Expression (N))
4019 and then Nkind (Expression (N)) = N_Aggregate
4025 Save_Typ : constant Entity_Id := Etype (Id);
4027 Set_Etype (Id, T); -- Temp. decoration for static checks
4028 Null_Exclusion_Static_Checks (N);
4029 Set_Etype (Id, Save_Typ);
4033 -- We might be dealing with an object of a composite type containing
4034 -- null-excluding components without an aggregate, so we must verify
4035 -- that such components have default initialization.
4038 Check_For_Null_Excluding_Components (T, N);
4042 -- Object is marked pure if it is in a pure scope
4044 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4046 -- If deferred constant, make sure context is appropriate. We detect
4047 -- a deferred constant as a constant declaration with no expression.
4048 -- A deferred constant can appear in a package body if its completion
4049 -- is by means of an interface pragma.
4051 if Constant_Present (N) and then No (E) then
4053 -- A deferred constant may appear in the declarative part of the
4054 -- following constructs:
4058 -- extended return statements
4061 -- subprogram bodies
4064 -- When declared inside a package spec, a deferred constant must be
4065 -- completed by a full constant declaration or pragma Import. In all
4066 -- other cases, the only proper completion is pragma Import. Extended
4067 -- return statements are flagged as invalid contexts because they do
4068 -- not have a declarative part and so cannot accommodate the pragma.
4070 if Ekind (Current_Scope) = E_Return_Statement then
4072 ("invalid context for deferred constant declaration (RM 7.4)",
4075 ("\declaration requires an initialization expression",
4077 Set_Constant_Present (N, False);
4079 -- In Ada 83, deferred constant must be of private type
4081 elsif not Is_Private_Type (T) then
4082 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
4084 ("(Ada 83) deferred constant must be private type", N);
4088 -- If not a deferred constant, then the object declaration freezes
4089 -- its type, unless the object is of an anonymous type and has delayed
4090 -- aspects. In that case the type is frozen when the object itself is.
4093 Check_Fully_Declared (T, N);
4095 if Has_Delayed_Aspects (Id)
4096 and then Is_Array_Type (T)
4097 and then Is_Itype (T)
4099 Set_Has_Delayed_Freeze (T);
4101 Freeze_Before (N, T);
4105 -- If the object was created by a constrained array definition, then
4106 -- set the link in both the anonymous base type and anonymous subtype
4107 -- that are built to represent the array type to point to the object.
4109 if Nkind (Object_Definition (Declaration_Node (Id))) =
4110 N_Constrained_Array_Definition
4112 Set_Related_Array_Object (T, Id);
4113 Set_Related_Array_Object (Base_Type (T), Id);
4116 -- Special checks for protected objects not at library level
4118 if Has_Protected (T) and then not Is_Library_Level_Entity (Id) then
4119 Check_Restriction (No_Local_Protected_Objects, Id);
4121 -- Protected objects with interrupt handlers must be at library level
4123 -- Ada 2005: This test is not needed (and the corresponding clause
4124 -- in the RM is removed) because accessibility checks are sufficient
4125 -- to make handlers not at the library level illegal.
4127 -- AI05-0303: The AI is in fact a binding interpretation, and thus
4128 -- applies to the '95 version of the language as well.
4130 if Is_Protected_Type (T)
4131 and then Has_Interrupt_Handler (T)
4132 and then Ada_Version < Ada_95
4135 ("interrupt object can only be declared at library level", Id);
4139 -- Check for violation of No_Local_Timing_Events
4141 if Has_Timing_Event (T) and then not Is_Library_Level_Entity (Id) then
4142 Check_Restriction (No_Local_Timing_Events, Id);
4145 -- The actual subtype of the object is the nominal subtype, unless
4146 -- the nominal one is unconstrained and obtained from the expression.
4150 -- These checks should be performed before the initialization expression
4151 -- is considered, so that the Object_Definition node is still the same
4152 -- as in source code.
4154 -- In SPARK, the nominal subtype is always given by a subtype mark
4155 -- and must not be unconstrained. (The only exception to this is the
4156 -- acceptance of declarations of constants of type String.)
4158 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
4160 Check_SPARK_05_Restriction
4161 ("subtype mark required", Object_Definition (N));
4163 elsif Is_Array_Type (T)
4164 and then not Is_Constrained (T)
4165 and then T /= Standard_String
4167 Check_SPARK_05_Restriction
4168 ("subtype mark of constrained type expected",
4169 Object_Definition (N));
4172 if Is_Library_Level_Entity (Id) then
4173 Check_Dynamic_Object (T);
4176 -- There are no aliased objects in SPARK
4178 if Aliased_Present (N) then
4179 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
4182 -- Process initialization expression if present and not in error
4184 if Present (E) and then E /= Error then
4186 -- Generate an error in case of CPP class-wide object initialization.
4187 -- Required because otherwise the expansion of the class-wide
4188 -- assignment would try to use 'size to initialize the object
4189 -- (primitive that is not available in CPP tagged types).
4191 if Is_Class_Wide_Type (Act_T)
4193 (Is_CPP_Class (Root_Type (Etype (Act_T)))
4195 (Present (Full_View (Root_Type (Etype (Act_T))))
4197 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
4200 ("predefined assignment not available for 'C'P'P tagged types",
4204 Mark_Coextensions (N, E);
4207 -- In case of errors detected in the analysis of the expression,
4208 -- decorate it with the expected type to avoid cascaded errors
4210 if No (Etype (E)) then
4214 -- If an initialization expression is present, then we set the
4215 -- Is_True_Constant flag. It will be reset if this is a variable
4216 -- and it is indeed modified.
4218 Set_Is_True_Constant (Id, True);
4220 -- If we are analyzing a constant declaration, set its completion
4221 -- flag after analyzing and resolving the expression.
4223 if Constant_Present (N) then
4224 Set_Has_Completion (Id);
4227 -- Set type and resolve (type may be overridden later on). Note:
4228 -- Ekind (Id) must still be E_Void at this point so that incorrect
4229 -- early usage within E is properly diagnosed.
4233 -- If the expression is an aggregate we must look ahead to detect
4234 -- the possible presence of an address clause, and defer resolution
4235 -- and expansion of the aggregate to the freeze point of the entity.
4237 -- This is not always legal because the aggregate may contain other
4238 -- references that need freezing, e.g. references to other entities
4239 -- with address clauses. In any case, when compiling with -gnatI the
4240 -- presence of the address clause must be ignored.
4242 if Comes_From_Source (N)
4243 and then Expander_Active
4244 and then Nkind (E) = N_Aggregate
4246 ((Present (Following_Address_Clause (N))
4247 and then not Ignore_Rep_Clauses)
4248 or else Delayed_Aspect_Present)
4256 -- No further action needed if E is a call to an inlined function
4257 -- which returns an unconstrained type and it has been expanded into
4258 -- a procedure call. In that case N has been replaced by an object
4259 -- declaration without initializing expression and it has been
4260 -- analyzed (see Expand_Inlined_Call).
4262 if Back_End_Inlining
4263 and then Expander_Active
4264 and then Nkind (E) = N_Function_Call
4265 and then Nkind (Name (E)) in N_Has_Entity
4266 and then Is_Inlined (Entity (Name (E)))
4267 and then not Is_Constrained (Etype (E))
4268 and then Analyzed (N)
4269 and then No (Expression (N))
4274 -- If E is null and has been replaced by an N_Raise_Constraint_Error
4275 -- node (which was marked already-analyzed), we need to set the type
4276 -- to something other than Any_Access in order to keep gigi happy.
4278 if Etype (E) = Any_Access then
4282 -- If the object is an access to variable, the initialization
4283 -- expression cannot be an access to constant.
4285 if Is_Access_Type (T)
4286 and then not Is_Access_Constant (T)
4287 and then Is_Access_Type (Etype (E))
4288 and then Is_Access_Constant (Etype (E))
4291 ("access to variable cannot be initialized with an "
4292 & "access-to-constant expression", E);
4295 if not Assignment_OK (N) then
4296 Check_Initialization (T, E);
4299 Check_Unset_Reference (E);
4301 -- If this is a variable, then set current value. If this is a
4302 -- declared constant of a scalar type with a static expression,
4303 -- indicate that it is always valid.
4305 if not Constant_Present (N) then
4306 if Compile_Time_Known_Value (E) then
4307 Set_Current_Value (Id, E);
4310 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
4311 Set_Is_Known_Valid (Id);
4314 -- Deal with setting of null flags
4316 if Is_Access_Type (T) then
4317 if Known_Non_Null (E) then
4318 Set_Is_Known_Non_Null (Id, True);
4319 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
4320 Set_Is_Known_Null (Id, True);
4324 -- Check incorrect use of dynamically tagged expressions
4326 if Is_Tagged_Type (T) then
4327 Check_Dynamically_Tagged_Expression
4333 Apply_Scalar_Range_Check (E, T);
4334 Apply_Static_Length_Check (E, T);
4336 if Nkind (Original_Node (N)) = N_Object_Declaration
4337 and then Comes_From_Source (Original_Node (N))
4339 -- Only call test if needed
4341 and then Restriction_Check_Required (SPARK_05)
4342 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
4344 Check_SPARK_05_Restriction
4345 ("initialization expression is not appropriate", E);
4348 -- A formal parameter of a specific tagged type whose related
4349 -- subprogram is subject to pragma Extensions_Visible with value
4350 -- "False" cannot be implicitly converted to a class-wide type by
4351 -- means of an initialization expression (SPARK RM 6.1.7(3)). Do
4352 -- not consider internally generated expressions.
4354 if Is_Class_Wide_Type (T)
4355 and then Comes_From_Source (E)
4356 and then Is_EVF_Expression (E)
4359 ("formal parameter cannot be implicitly converted to "
4360 & "class-wide type when Extensions_Visible is False", E);
4364 -- If the No_Streams restriction is set, check that the type of the
4365 -- object is not, and does not contain, any subtype derived from
4366 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
4367 -- Has_Stream just for efficiency reasons. There is no point in
4368 -- spending time on a Has_Stream check if the restriction is not set.
4370 if Restriction_Check_Required (No_Streams) then
4371 if Has_Stream (T) then
4372 Check_Restriction (No_Streams, N);
4376 -- Deal with predicate check before we start to do major rewriting. It
4377 -- is OK to initialize and then check the initialized value, since the
4378 -- object goes out of scope if we get a predicate failure. Note that we
4379 -- do this in the analyzer and not the expander because the analyzer
4380 -- does some substantial rewriting in some cases.
4382 -- We need a predicate check if the type has predicates that are not
4383 -- ignored, and if either there is an initializing expression, or for
4384 -- default initialization when we have at least one case of an explicit
4385 -- default initial value and then this is not an internal declaration
4386 -- whose initialization comes later (as for an aggregate expansion).
4388 if not Suppress_Assignment_Checks (N)
4389 and then Present (Predicate_Function (T))
4390 and then not Predicates_Ignored (T)
4391 and then not No_Initialization (N)
4395 Is_Partially_Initialized_Type (T, Include_Implicit => False))
4397 -- If the type has a static predicate and the expression is known at
4398 -- compile time, see if the expression satisfies the predicate.
4401 Check_Expression_Against_Static_Predicate (E, T);
4404 -- If the type is a null record and there is no explicit initial
4405 -- expression, no predicate check applies.
4407 if No (E) and then Is_Null_Record_Type (T) then
4410 -- Do not generate a predicate check if the initialization expression
4411 -- is a type conversion because the conversion has been subjected to
4412 -- the same check. This is a small optimization which avoid redundant
4415 elsif Present (E) and then Nkind (E) = N_Type_Conversion then
4420 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
4424 -- Case of unconstrained type
4426 if not Is_Definite_Subtype (T) then
4428 -- In SPARK, a declaration of unconstrained type is allowed
4429 -- only for constants of type string.
4431 if Is_String_Type (T) and then not Constant_Present (N) then
4432 Check_SPARK_05_Restriction
4433 ("declaration of object of unconstrained type not allowed", N);
4436 -- Nothing to do in deferred constant case
4438 if Constant_Present (N) and then No (E) then
4441 -- Case of no initialization present
4444 if No_Initialization (N) then
4447 elsif Is_Class_Wide_Type (T) then
4449 ("initialization required in class-wide declaration ", N);
4453 ("unconstrained subtype not allowed (need initialization)",
4454 Object_Definition (N));
4456 if Is_Record_Type (T) and then Has_Discriminants (T) then
4458 ("\provide initial value or explicit discriminant values",
4459 Object_Definition (N));
4462 ("\or give default discriminant values for type&",
4463 Object_Definition (N), T);
4465 elsif Is_Array_Type (T) then
4467 ("\provide initial value or explicit array bounds",
4468 Object_Definition (N));
4472 -- Case of initialization present but in error. Set initial
4473 -- expression as absent (but do not make above complaints)
4475 elsif E = Error then
4476 Set_Expression (N, Empty);
4479 -- Case of initialization present
4482 -- Check restrictions in Ada 83
4484 if not Constant_Present (N) then
4486 -- Unconstrained variables not allowed in Ada 83 mode
4488 if Ada_Version = Ada_83
4489 and then Comes_From_Source (Object_Definition (N))
4492 ("(Ada 83) unconstrained variable not allowed",
4493 Object_Definition (N));
4497 -- Now we constrain the variable from the initializing expression
4499 -- If the expression is an aggregate, it has been expanded into
4500 -- individual assignments. Retrieve the actual type from the
4501 -- expanded construct.
4503 if Is_Array_Type (T)
4504 and then No_Initialization (N)
4505 and then Nkind (Original_Node (E)) = N_Aggregate
4509 -- In case of class-wide interface object declarations we delay
4510 -- the generation of the equivalent record type declarations until
4511 -- its expansion because there are cases in they are not required.
4513 elsif Is_Interface (T) then
4516 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
4517 -- we should prevent the generation of another Itype with the
4518 -- same name as the one already generated, or we end up with
4519 -- two identical types in GNATprove.
4521 elsif GNATprove_Mode then
4524 -- If the type is an unchecked union, no subtype can be built from
4525 -- the expression. Rewrite declaration as a renaming, which the
4526 -- back-end can handle properly. This is a rather unusual case,
4527 -- because most unchecked_union declarations have default values
4528 -- for discriminants and are thus not indefinite.
4530 elsif Is_Unchecked_Union (T) then
4531 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4532 Set_Ekind (Id, E_Constant);
4534 Set_Ekind (Id, E_Variable);
4538 Make_Object_Renaming_Declaration (Loc,
4539 Defining_Identifier => Id,
4540 Subtype_Mark => New_Occurrence_Of (T, Loc),
4543 Set_Renamed_Object (Id, E);
4544 Freeze_Before (N, T);
4549 -- Ensure that the generated subtype has a unique external name
4550 -- when the related object is public. This guarantees that the
4551 -- subtype and its bounds will not be affected by switches or
4552 -- pragmas that may offset the internal counter due to extra
4555 if Is_Public (Id) then
4558 Related_Id := Empty;
4561 Expand_Subtype_From_Expr
4564 Subtype_Indic => Object_Definition (N),
4566 Related_Id => Related_Id);
4568 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4571 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4573 if Aliased_Present (N) then
4574 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4577 Freeze_Before (N, Act_T);
4578 Freeze_Before (N, T);
4581 elsif Is_Array_Type (T)
4582 and then No_Initialization (N)
4583 and then (Nkind (Original_Node (E)) = N_Aggregate
4584 or else (Nkind (Original_Node (E)) = N_Qualified_Expression
4585 and then Nkind (Original_Node (Expression
4586 (Original_Node (E)))) = N_Aggregate))
4588 if not Is_Entity_Name (Object_Definition (N)) then
4590 Check_Compile_Time_Size (Act_T);
4592 if Aliased_Present (N) then
4593 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4597 -- When the given object definition and the aggregate are specified
4598 -- independently, and their lengths might differ do a length check.
4599 -- This cannot happen if the aggregate is of the form (others =>...)
4601 if not Is_Constrained (T) then
4604 elsif Nkind (E) = N_Raise_Constraint_Error then
4606 -- Aggregate is statically illegal. Place back in declaration
4608 Set_Expression (N, E);
4609 Set_No_Initialization (N, False);
4611 elsif T = Etype (E) then
4614 elsif Nkind (E) = N_Aggregate
4615 and then Present (Component_Associations (E))
4616 and then Present (Choice_List (First (Component_Associations (E))))
4618 Nkind (First (Choice_List (First (Component_Associations (E))))) =
4624 Apply_Length_Check (E, T);
4627 -- If the type is limited unconstrained with defaulted discriminants and
4628 -- there is no expression, then the object is constrained by the
4629 -- defaults, so it is worthwhile building the corresponding subtype.
4631 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4632 and then not Is_Constrained (T)
4633 and then Has_Discriminants (T)
4636 Act_T := Build_Default_Subtype (T, N);
4638 -- Ada 2005: A limited object may be initialized by means of an
4639 -- aggregate. If the type has default discriminants it has an
4640 -- unconstrained nominal type, Its actual subtype will be obtained
4641 -- from the aggregate, and not from the default discriminants.
4646 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4648 elsif Nkind (E) = N_Function_Call
4649 and then Constant_Present (N)
4650 and then Has_Unconstrained_Elements (Etype (E))
4652 -- The back-end has problems with constants of a discriminated type
4653 -- with defaults, if the initial value is a function call. We
4654 -- generate an intermediate temporary that will receive a reference
4655 -- to the result of the call. The initialization expression then
4656 -- becomes a dereference of that temporary.
4658 Remove_Side_Effects (E);
4660 -- If this is a constant declaration of an unconstrained type and
4661 -- the initialization is an aggregate, we can use the subtype of the
4662 -- aggregate for the declared entity because it is immutable.
4664 elsif not Is_Constrained (T)
4665 and then Has_Discriminants (T)
4666 and then Constant_Present (N)
4667 and then not Has_Unchecked_Union (T)
4668 and then Nkind (E) = N_Aggregate
4673 -- Check No_Wide_Characters restriction
4675 Check_Wide_Character_Restriction (T, Object_Definition (N));
4677 -- Indicate this is not set in source. Certainly true for constants, and
4678 -- true for variables so far (will be reset for a variable if and when
4679 -- we encounter a modification in the source).
4681 Set_Never_Set_In_Source (Id);
4683 -- Now establish the proper kind and type of the object
4685 if Constant_Present (N) then
4686 Set_Ekind (Id, E_Constant);
4687 Set_Is_True_Constant (Id);
4690 Set_Ekind (Id, E_Variable);
4692 -- A variable is set as shared passive if it appears in a shared
4693 -- passive package, and is at the outer level. This is not done for
4694 -- entities generated during expansion, because those are always
4695 -- manipulated locally.
4697 if Is_Shared_Passive (Current_Scope)
4698 and then Is_Library_Level_Entity (Id)
4699 and then Comes_From_Source (Id)
4701 Set_Is_Shared_Passive (Id);
4702 Check_Shared_Var (Id, T, N);
4705 -- Set Has_Initial_Value if initializing expression present. Note
4706 -- that if there is no initializing expression, we leave the state
4707 -- of this flag unchanged (usually it will be False, but notably in
4708 -- the case of exception choice variables, it will already be true).
4711 Set_Has_Initial_Value (Id);
4715 -- Set the SPARK mode from the current context (may be overwritten later
4716 -- with explicit pragma).
4718 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
4719 Set_SPARK_Pragma_Inherited (Id);
4721 -- Preserve relevant elaboration-related attributes of the context which
4722 -- are no longer available or very expensive to recompute once analysis,
4723 -- resolution, and expansion are over.
4725 Mark_Elaboration_Attributes
4729 -- Initialize alignment and size and capture alignment setting
4731 Init_Alignment (Id);
4733 Set_Optimize_Alignment_Flags (Id);
4735 -- Deal with aliased case
4737 if Aliased_Present (N) then
4738 Set_Is_Aliased (Id);
4740 -- If the object is aliased and the type is unconstrained with
4741 -- defaulted discriminants and there is no expression, then the
4742 -- object is constrained by the defaults, so it is worthwhile
4743 -- building the corresponding subtype.
4745 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4746 -- unconstrained, then only establish an actual subtype if the
4747 -- nominal subtype is indefinite. In definite cases the object is
4748 -- unconstrained in Ada 2005.
4751 and then Is_Record_Type (T)
4752 and then not Is_Constrained (T)
4753 and then Has_Discriminants (T)
4754 and then (Ada_Version < Ada_2005
4755 or else not Is_Definite_Subtype (T))
4757 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4761 -- Now we can set the type of the object
4763 Set_Etype (Id, Act_T);
4765 -- Non-constant object is marked to be treated as volatile if type is
4766 -- volatile and we clear the Current_Value setting that may have been
4767 -- set above. Doing so for constants isn't required and might interfere
4768 -- with possible uses of the object as a static expression in contexts
4769 -- incompatible with volatility (e.g. as a case-statement alternative).
4771 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4772 Set_Treat_As_Volatile (Id);
4773 Set_Current_Value (Id, Empty);
4776 -- Deal with controlled types
4778 if Has_Controlled_Component (Etype (Id))
4779 or else Is_Controlled (Etype (Id))
4781 if not Is_Library_Level_Entity (Id) then
4782 Check_Restriction (No_Nested_Finalization, N);
4784 Validate_Controlled_Object (Id);
4788 if Has_Task (Etype (Id)) then
4789 Check_Restriction (No_Tasking, N);
4791 -- Deal with counting max tasks
4793 -- Nothing to do if inside a generic
4795 if Inside_A_Generic then
4798 -- If library level entity, then count tasks
4800 elsif Is_Library_Level_Entity (Id) then
4801 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4803 -- If not library level entity, then indicate we don't know max
4804 -- tasks and also check task hierarchy restriction and blocking
4805 -- operation (since starting a task is definitely blocking).
4808 Check_Restriction (Max_Tasks, N);
4809 Check_Restriction (No_Task_Hierarchy, N);
4810 Check_Potentially_Blocking_Operation (N);
4813 -- A rather specialized test. If we see two tasks being declared
4814 -- of the same type in the same object declaration, and the task
4815 -- has an entry with an address clause, we know that program error
4816 -- will be raised at run time since we can't have two tasks with
4817 -- entries at the same address.
4819 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4824 E := First_Entity (Etype (Id));
4825 while Present (E) loop
4826 if Ekind (E) = E_Entry
4827 and then Present (Get_Attribute_Definition_Clause
4828 (E, Attribute_Address))
4830 Error_Msg_Warn := SPARK_Mode /= On;
4832 ("more than one task with same entry address<<", N);
4833 Error_Msg_N ("\Program_Error [<<", N);
4835 Make_Raise_Program_Error (Loc,
4836 Reason => PE_Duplicated_Entry_Address));
4846 -- Some simple constant-propagation: if the expression is a constant
4847 -- string initialized with a literal, share the literal. This avoids
4851 and then Is_Entity_Name (E)
4852 and then Ekind (Entity (E)) = E_Constant
4853 and then Base_Type (Etype (E)) = Standard_String
4856 Val : constant Node_Id := Constant_Value (Entity (E));
4858 if Present (Val) and then Nkind (Val) = N_String_Literal then
4859 Rewrite (E, New_Copy (Val));
4864 -- Another optimization: if the nominal subtype is unconstrained and
4865 -- the expression is a function call that returns an unconstrained
4866 -- type, rewrite the declaration as a renaming of the result of the
4867 -- call. The exceptions below are cases where the copy is expected,
4868 -- either by the back end (Aliased case) or by the semantics, as for
4869 -- initializing controlled types or copying tags for class-wide types.
4872 and then Nkind (E) = N_Explicit_Dereference
4873 and then Nkind (Original_Node (E)) = N_Function_Call
4874 and then not Is_Library_Level_Entity (Id)
4875 and then not Is_Constrained (Underlying_Type (T))
4876 and then not Is_Aliased (Id)
4877 and then not Is_Class_Wide_Type (T)
4878 and then not Is_Controlled (T)
4879 and then not Has_Controlled_Component (Base_Type (T))
4880 and then Expander_Active
4883 Make_Object_Renaming_Declaration (Loc,
4884 Defining_Identifier => Id,
4885 Access_Definition => Empty,
4886 Subtype_Mark => New_Occurrence_Of
4887 (Base_Type (Etype (Id)), Loc),
4890 Set_Renamed_Object (Id, E);
4892 -- Force generation of debugging information for the constant and for
4893 -- the renamed function call.
4895 Set_Debug_Info_Needed (Id);
4896 Set_Debug_Info_Needed (Entity (Prefix (E)));
4899 if Present (Prev_Entity)
4900 and then Is_Frozen (Prev_Entity)
4901 and then not Error_Posted (Id)
4903 Error_Msg_N ("full constant declaration appears too late", N);
4906 Check_Eliminated (Id);
4908 -- Deal with setting In_Private_Part flag if in private part
4910 if Ekind (Scope (Id)) = E_Package
4911 and then In_Private_Part (Scope (Id))
4913 Set_In_Private_Part (Id);
4917 -- Initialize the refined state of a variable here because this is a
4918 -- common destination for legal and illegal object declarations.
4920 if Ekind (Id) = E_Variable then
4921 Set_Encapsulating_State (Id, Empty);
4924 if Has_Aspects (N) then
4925 Analyze_Aspect_Specifications (N, Id);
4928 Analyze_Dimension (N);
4930 -- Verify whether the object declaration introduces an illegal hidden
4931 -- state within a package subject to a null abstract state.
4933 if Ekind (Id) = E_Variable then
4934 Check_No_Hidden_State (Id);
4937 Restore_Ghost_Mode (Saved_GM);
4938 end Analyze_Object_Declaration;
4940 ---------------------------
4941 -- Analyze_Others_Choice --
4942 ---------------------------
4944 -- Nothing to do for the others choice node itself, the semantic analysis
4945 -- of the others choice will occur as part of the processing of the parent
4947 procedure Analyze_Others_Choice (N : Node_Id) is
4948 pragma Warnings (Off, N);
4951 end Analyze_Others_Choice;
4953 -------------------------------------------
4954 -- Analyze_Private_Extension_Declaration --
4955 -------------------------------------------
4957 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4958 Indic : constant Node_Id := Subtype_Indication (N);
4959 T : constant Entity_Id := Defining_Identifier (N);
4961 Iface_Elmt : Elmt_Id;
4962 Parent_Base : Entity_Id;
4963 Parent_Type : Entity_Id;
4966 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4968 if Is_Non_Empty_List (Interface_List (N)) then
4974 Intf := First (Interface_List (N));
4975 while Present (Intf) loop
4976 T := Find_Type_Of_Subtype_Indic (Intf);
4978 Diagnose_Interface (Intf, T);
4984 Generate_Definition (T);
4986 -- For other than Ada 2012, just enter the name in the current scope
4988 if Ada_Version < Ada_2012 then
4991 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4992 -- case of private type that completes an incomplete type.
4999 Prev := Find_Type_Name (N);
5001 pragma Assert (Prev = T
5002 or else (Ekind (Prev) = E_Incomplete_Type
5003 and then Present (Full_View (Prev))
5004 and then Full_View (Prev) = T));
5008 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
5009 Parent_Base := Base_Type (Parent_Type);
5011 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
5012 Set_Ekind (T, Ekind (Parent_Type));
5013 Set_Etype (T, Any_Type);
5016 elsif not Is_Tagged_Type (Parent_Type) then
5018 ("parent of type extension must be a tagged type ", Indic);
5021 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
5022 Error_Msg_N ("premature derivation of incomplete type", Indic);
5025 elsif Is_Concurrent_Type (Parent_Type) then
5027 ("parent type of a private extension cannot be a synchronized "
5028 & "tagged type (RM 3.9.1 (3/1))", N);
5030 Set_Etype (T, Any_Type);
5031 Set_Ekind (T, E_Limited_Private_Type);
5032 Set_Private_Dependents (T, New_Elmt_List);
5033 Set_Error_Posted (T);
5037 -- Perhaps the parent type should be changed to the class-wide type's
5038 -- specific type in this case to prevent cascading errors ???
5040 if Is_Class_Wide_Type (Parent_Type) then
5042 ("parent of type extension must not be a class-wide type", Indic);
5046 if (not Is_Package_Or_Generic_Package (Current_Scope)
5047 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
5048 or else In_Private_Part (Current_Scope)
5050 Error_Msg_N ("invalid context for private extension", N);
5053 -- Set common attributes
5055 Set_Is_Pure (T, Is_Pure (Current_Scope));
5056 Set_Scope (T, Current_Scope);
5057 Set_Ekind (T, E_Record_Type_With_Private);
5058 Init_Size_Align (T);
5059 Set_Default_SSO (T);
5060 Set_No_Reordering (T, No_Component_Reordering);
5062 Set_Etype (T, Parent_Base);
5063 Propagate_Concurrent_Flags (T, Parent_Base);
5065 Set_Convention (T, Convention (Parent_Type));
5066 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
5067 Set_Is_First_Subtype (T);
5068 Make_Class_Wide_Type (T);
5070 if Unknown_Discriminants_Present (N) then
5071 Set_Discriminant_Constraint (T, No_Elist);
5074 Build_Derived_Record_Type (N, Parent_Type, T);
5076 -- A private extension inherits the Default_Initial_Condition pragma
5077 -- coming from any parent type within the derivation chain.
5079 if Has_DIC (Parent_Type) then
5080 Set_Has_Inherited_DIC (T);
5083 -- A private extension inherits any class-wide invariants coming from a
5084 -- parent type or an interface. Note that the invariant procedure of the
5085 -- parent type should not be inherited because the private extension may
5086 -- define invariants of its own.
5088 if Has_Inherited_Invariants (Parent_Type)
5089 or else Has_Inheritable_Invariants (Parent_Type)
5091 Set_Has_Inherited_Invariants (T);
5093 elsif Present (Interfaces (T)) then
5094 Iface_Elmt := First_Elmt (Interfaces (T));
5095 while Present (Iface_Elmt) loop
5096 Iface := Node (Iface_Elmt);
5098 if Has_Inheritable_Invariants (Iface) then
5099 Set_Has_Inherited_Invariants (T);
5103 Next_Elmt (Iface_Elmt);
5107 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
5108 -- synchronized formal derived type.
5110 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
5111 Set_Is_Limited_Record (T);
5113 -- Formal derived type case
5115 if Is_Generic_Type (T) then
5117 -- The parent must be a tagged limited type or a synchronized
5120 if (not Is_Tagged_Type (Parent_Type)
5121 or else not Is_Limited_Type (Parent_Type))
5123 (not Is_Interface (Parent_Type)
5124 or else not Is_Synchronized_Interface (Parent_Type))
5127 ("parent type of & must be tagged limited or synchronized",
5131 -- The progenitors (if any) must be limited or synchronized
5134 if Present (Interfaces (T)) then
5135 Iface_Elmt := First_Elmt (Interfaces (T));
5136 while Present (Iface_Elmt) loop
5137 Iface := Node (Iface_Elmt);
5139 if not Is_Limited_Interface (Iface)
5140 and then not Is_Synchronized_Interface (Iface)
5143 ("progenitor & must be limited or synchronized",
5147 Next_Elmt (Iface_Elmt);
5151 -- Regular derived extension, the parent must be a limited or
5152 -- synchronized interface.
5155 if not Is_Interface (Parent_Type)
5156 or else (not Is_Limited_Interface (Parent_Type)
5157 and then not Is_Synchronized_Interface (Parent_Type))
5160 ("parent type of & must be limited interface", N, T);
5164 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
5165 -- extension with a synchronized parent must be explicitly declared
5166 -- synchronized, because the full view will be a synchronized type.
5167 -- This must be checked before the check for limited types below,
5168 -- to ensure that types declared limited are not allowed to extend
5169 -- synchronized interfaces.
5171 elsif Is_Interface (Parent_Type)
5172 and then Is_Synchronized_Interface (Parent_Type)
5173 and then not Synchronized_Present (N)
5176 ("private extension of& must be explicitly synchronized",
5179 elsif Limited_Present (N) then
5180 Set_Is_Limited_Record (T);
5182 if not Is_Limited_Type (Parent_Type)
5184 (not Is_Interface (Parent_Type)
5185 or else not Is_Limited_Interface (Parent_Type))
5187 Error_Msg_NE ("parent type& of limited extension must be limited",
5192 -- Remember that its parent type has a private extension. Used to warn
5193 -- on public primitives of the parent type defined after its private
5194 -- extensions (see Check_Dispatching_Operation).
5196 Set_Has_Private_Extension (Parent_Type);
5199 if Has_Aspects (N) then
5200 Analyze_Aspect_Specifications (N, T);
5202 end Analyze_Private_Extension_Declaration;
5204 ---------------------------------
5205 -- Analyze_Subtype_Declaration --
5206 ---------------------------------
5208 procedure Analyze_Subtype_Declaration
5210 Skip : Boolean := False)
5212 Id : constant Entity_Id := Defining_Identifier (N);
5213 R_Checks : Check_Result;
5217 Generate_Definition (Id);
5218 Set_Is_Pure (Id, Is_Pure (Current_Scope));
5219 Init_Size_Align (Id);
5221 -- The following guard condition on Enter_Name is to handle cases where
5222 -- the defining identifier has already been entered into the scope but
5223 -- the declaration as a whole needs to be analyzed.
5225 -- This case in particular happens for derived enumeration types. The
5226 -- derived enumeration type is processed as an inserted enumeration type
5227 -- declaration followed by a rewritten subtype declaration. The defining
5228 -- identifier, however, is entered into the name scope very early in the
5229 -- processing of the original type declaration and therefore needs to be
5230 -- avoided here, when the created subtype declaration is analyzed. (See
5231 -- Build_Derived_Types)
5233 -- This also happens when the full view of a private type is derived
5234 -- type with constraints. In this case the entity has been introduced
5235 -- in the private declaration.
5237 -- Finally this happens in some complex cases when validity checks are
5238 -- enabled, where the same subtype declaration may be analyzed twice.
5239 -- This can happen if the subtype is created by the pre-analysis of
5240 -- an attribute tht gives the range of a loop statement, and the loop
5241 -- itself appears within an if_statement that will be rewritten during
5245 or else (Present (Etype (Id))
5246 and then (Is_Private_Type (Etype (Id))
5247 or else Is_Task_Type (Etype (Id))
5248 or else Is_Rewrite_Substitution (N)))
5252 elsif Current_Entity (Id) = Id then
5259 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
5261 -- Class-wide equivalent types of records with unknown discriminants
5262 -- involve the generation of an itype which serves as the private view
5263 -- of a constrained record subtype. In such cases the base type of the
5264 -- current subtype we are processing is the private itype. Use the full
5265 -- of the private itype when decorating various attributes.
5268 and then Is_Private_Type (T)
5269 and then Present (Full_View (T))
5274 -- Inherit common attributes
5276 Set_Is_Volatile (Id, Is_Volatile (T));
5277 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
5278 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
5279 Set_Convention (Id, Convention (T));
5281 -- If ancestor has predicates then so does the subtype, and in addition
5282 -- we must delay the freeze to properly arrange predicate inheritance.
5284 -- The Ancestor_Type test is really unpleasant, there seem to be cases
5285 -- in which T = ID, so the above tests and assignments do nothing???
5287 if Has_Predicates (T)
5288 or else (Present (Ancestor_Subtype (T))
5289 and then Has_Predicates (Ancestor_Subtype (T)))
5291 Set_Has_Predicates (Id);
5292 Set_Has_Delayed_Freeze (Id);
5294 -- Generated subtypes inherit the predicate function from the parent
5295 -- (no aspects to examine on the generated declaration).
5297 if not Comes_From_Source (N) then
5298 Set_Ekind (Id, Ekind (T));
5300 if Present (Predicate_Function (T)) then
5301 Set_Predicate_Function (Id, Predicate_Function (T));
5303 elsif Present (Ancestor_Subtype (T))
5304 and then Has_Predicates (Ancestor_Subtype (T))
5305 and then Present (Predicate_Function (Ancestor_Subtype (T)))
5307 Set_Predicate_Function (Id,
5308 Predicate_Function (Ancestor_Subtype (T)));
5313 -- Subtype of Boolean cannot have a constraint in SPARK
5315 if Is_Boolean_Type (T)
5316 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
5318 Check_SPARK_05_Restriction
5319 ("subtype of Boolean cannot have constraint", N);
5322 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5324 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5330 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
5331 One_Cstr := First (Constraints (Cstr));
5332 while Present (One_Cstr) loop
5334 -- Index or discriminant constraint in SPARK must be a
5338 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
5340 Check_SPARK_05_Restriction
5341 ("subtype mark required", One_Cstr);
5343 -- String subtype must have a lower bound of 1 in SPARK.
5344 -- Note that we do not need to test for the non-static case
5345 -- here, since that was already taken care of in
5346 -- Process_Range_Expr_In_Decl.
5348 elsif Base_Type (T) = Standard_String then
5349 Get_Index_Bounds (One_Cstr, Low, High);
5351 if Is_OK_Static_Expression (Low)
5352 and then Expr_Value (Low) /= 1
5354 Check_SPARK_05_Restriction
5355 ("String subtype must have lower bound of 1", N);
5365 -- In the case where there is no constraint given in the subtype
5366 -- indication, Process_Subtype just returns the Subtype_Mark, so its
5367 -- semantic attributes must be established here.
5369 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
5370 Set_Etype (Id, Base_Type (T));
5372 -- Subtype of unconstrained array without constraint is not allowed
5375 if Is_Array_Type (T) and then not Is_Constrained (T) then
5376 Check_SPARK_05_Restriction
5377 ("subtype of unconstrained array must have constraint", N);
5382 Set_Ekind (Id, E_Array_Subtype);
5383 Copy_Array_Subtype_Attributes (Id, T);
5385 when Decimal_Fixed_Point_Kind =>
5386 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
5387 Set_Digits_Value (Id, Digits_Value (T));
5388 Set_Delta_Value (Id, Delta_Value (T));
5389 Set_Scale_Value (Id, Scale_Value (T));
5390 Set_Small_Value (Id, Small_Value (T));
5391 Set_Scalar_Range (Id, Scalar_Range (T));
5392 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
5393 Set_Is_Constrained (Id, Is_Constrained (T));
5394 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5395 Set_RM_Size (Id, RM_Size (T));
5397 when Enumeration_Kind =>
5398 Set_Ekind (Id, E_Enumeration_Subtype);
5399 Set_First_Literal (Id, First_Literal (Base_Type (T)));
5400 Set_Scalar_Range (Id, Scalar_Range (T));
5401 Set_Is_Character_Type (Id, Is_Character_Type (T));
5402 Set_Is_Constrained (Id, Is_Constrained (T));
5403 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5404 Set_RM_Size (Id, RM_Size (T));
5405 Inherit_Predicate_Flags (Id, T);
5407 when Ordinary_Fixed_Point_Kind =>
5408 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
5409 Set_Scalar_Range (Id, Scalar_Range (T));
5410 Set_Small_Value (Id, Small_Value (T));
5411 Set_Delta_Value (Id, Delta_Value (T));
5412 Set_Is_Constrained (Id, Is_Constrained (T));
5413 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5414 Set_RM_Size (Id, RM_Size (T));
5417 Set_Ekind (Id, E_Floating_Point_Subtype);
5418 Set_Scalar_Range (Id, Scalar_Range (T));
5419 Set_Digits_Value (Id, Digits_Value (T));
5420 Set_Is_Constrained (Id, Is_Constrained (T));
5422 -- If the floating point type has dimensions, these will be
5423 -- inherited subsequently when Analyze_Dimensions is called.
5425 when Signed_Integer_Kind =>
5426 Set_Ekind (Id, E_Signed_Integer_Subtype);
5427 Set_Scalar_Range (Id, Scalar_Range (T));
5428 Set_Is_Constrained (Id, Is_Constrained (T));
5429 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5430 Set_RM_Size (Id, RM_Size (T));
5431 Inherit_Predicate_Flags (Id, T);
5433 when Modular_Integer_Kind =>
5434 Set_Ekind (Id, E_Modular_Integer_Subtype);
5435 Set_Scalar_Range (Id, Scalar_Range (T));
5436 Set_Is_Constrained (Id, Is_Constrained (T));
5437 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5438 Set_RM_Size (Id, RM_Size (T));
5439 Inherit_Predicate_Flags (Id, T);
5441 when Class_Wide_Kind =>
5442 Set_Ekind (Id, E_Class_Wide_Subtype);
5443 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5444 Set_Cloned_Subtype (Id, T);
5445 Set_Is_Tagged_Type (Id, True);
5446 Set_Has_Unknown_Discriminants
5448 Set_No_Tagged_Streams_Pragma
5449 (Id, No_Tagged_Streams_Pragma (T));
5451 if Ekind (T) = E_Class_Wide_Subtype then
5452 Set_Equivalent_Type (Id, Equivalent_Type (T));
5455 when E_Record_Subtype
5458 Set_Ekind (Id, E_Record_Subtype);
5460 if Ekind (T) = E_Record_Subtype
5461 and then Present (Cloned_Subtype (T))
5463 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
5465 Set_Cloned_Subtype (Id, T);
5468 Set_First_Entity (Id, First_Entity (T));
5469 Set_Last_Entity (Id, Last_Entity (T));
5470 Set_Has_Discriminants (Id, Has_Discriminants (T));
5471 Set_Is_Constrained (Id, Is_Constrained (T));
5472 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5473 Set_Has_Implicit_Dereference
5474 (Id, Has_Implicit_Dereference (T));
5475 Set_Has_Unknown_Discriminants
5476 (Id, Has_Unknown_Discriminants (T));
5478 if Has_Discriminants (T) then
5479 Set_Discriminant_Constraint
5480 (Id, Discriminant_Constraint (T));
5481 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5483 elsif Has_Unknown_Discriminants (Id) then
5484 Set_Discriminant_Constraint (Id, No_Elist);
5487 if Is_Tagged_Type (T) then
5488 Set_Is_Tagged_Type (Id, True);
5489 Set_No_Tagged_Streams_Pragma
5490 (Id, No_Tagged_Streams_Pragma (T));
5491 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5492 Set_Direct_Primitive_Operations
5493 (Id, Direct_Primitive_Operations (T));
5494 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5496 if Is_Interface (T) then
5497 Set_Is_Interface (Id);
5498 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
5502 when Private_Kind =>
5503 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5504 Set_Has_Discriminants (Id, Has_Discriminants (T));
5505 Set_Is_Constrained (Id, Is_Constrained (T));
5506 Set_First_Entity (Id, First_Entity (T));
5507 Set_Last_Entity (Id, Last_Entity (T));
5508 Set_Private_Dependents (Id, New_Elmt_List);
5509 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5510 Set_Has_Implicit_Dereference
5511 (Id, Has_Implicit_Dereference (T));
5512 Set_Has_Unknown_Discriminants
5513 (Id, Has_Unknown_Discriminants (T));
5514 Set_Known_To_Have_Preelab_Init
5515 (Id, Known_To_Have_Preelab_Init (T));
5517 if Is_Tagged_Type (T) then
5518 Set_Is_Tagged_Type (Id);
5519 Set_No_Tagged_Streams_Pragma (Id,
5520 No_Tagged_Streams_Pragma (T));
5521 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5522 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5523 Set_Direct_Primitive_Operations (Id,
5524 Direct_Primitive_Operations (T));
5527 -- In general the attributes of the subtype of a private type
5528 -- are the attributes of the partial view of parent. However,
5529 -- the full view may be a discriminated type, and the subtype
5530 -- must share the discriminant constraint to generate correct
5531 -- calls to initialization procedures.
5533 if Has_Discriminants (T) then
5534 Set_Discriminant_Constraint
5535 (Id, Discriminant_Constraint (T));
5536 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5538 elsif Present (Full_View (T))
5539 and then Has_Discriminants (Full_View (T))
5541 Set_Discriminant_Constraint
5542 (Id, Discriminant_Constraint (Full_View (T)));
5543 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5545 -- This would seem semantically correct, but apparently
5546 -- generates spurious errors about missing components ???
5548 -- Set_Has_Discriminants (Id);
5551 Prepare_Private_Subtype_Completion (Id, N);
5553 -- If this is the subtype of a constrained private type with
5554 -- discriminants that has got a full view and we also have
5555 -- built a completion just above, show that the completion
5556 -- is a clone of the full view to the back-end.
5558 if Has_Discriminants (T)
5559 and then not Has_Unknown_Discriminants (T)
5560 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5561 and then Present (Full_View (T))
5562 and then Present (Full_View (Id))
5564 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5568 Set_Ekind (Id, E_Access_Subtype);
5569 Set_Is_Constrained (Id, Is_Constrained (T));
5570 Set_Is_Access_Constant
5571 (Id, Is_Access_Constant (T));
5572 Set_Directly_Designated_Type
5573 (Id, Designated_Type (T));
5574 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5576 -- A Pure library_item must not contain the declaration of a
5577 -- named access type, except within a subprogram, generic
5578 -- subprogram, task unit, or protected unit, or if it has
5579 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5581 if Comes_From_Source (Id)
5582 and then In_Pure_Unit
5583 and then not In_Subprogram_Task_Protected_Unit
5584 and then not No_Pool_Assigned (Id)
5587 ("named access types not allowed in pure unit", N);
5590 when Concurrent_Kind =>
5591 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5592 Set_Corresponding_Record_Type (Id,
5593 Corresponding_Record_Type (T));
5594 Set_First_Entity (Id, First_Entity (T));
5595 Set_First_Private_Entity (Id, First_Private_Entity (T));
5596 Set_Has_Discriminants (Id, Has_Discriminants (T));
5597 Set_Is_Constrained (Id, Is_Constrained (T));
5598 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5599 Set_Last_Entity (Id, Last_Entity (T));
5601 if Is_Tagged_Type (T) then
5602 Set_No_Tagged_Streams_Pragma
5603 (Id, No_Tagged_Streams_Pragma (T));
5606 if Has_Discriminants (T) then
5607 Set_Discriminant_Constraint
5608 (Id, Discriminant_Constraint (T));
5609 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5612 when Incomplete_Kind =>
5613 if Ada_Version >= Ada_2005 then
5615 -- In Ada 2005 an incomplete type can be explicitly tagged:
5616 -- propagate indication. Note that we also have to include
5617 -- subtypes for Ada 2012 extended use of incomplete types.
5619 Set_Ekind (Id, E_Incomplete_Subtype);
5620 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5621 Set_Private_Dependents (Id, New_Elmt_List);
5623 if Is_Tagged_Type (Id) then
5624 Set_No_Tagged_Streams_Pragma
5625 (Id, No_Tagged_Streams_Pragma (T));
5626 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5629 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5630 -- incomplete type visible through a limited with clause.
5632 if From_Limited_With (T)
5633 and then Present (Non_Limited_View (T))
5635 Set_From_Limited_With (Id);
5636 Set_Non_Limited_View (Id, Non_Limited_View (T));
5638 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5639 -- to the private dependents of the original incomplete
5640 -- type for future transformation.
5643 Append_Elmt (Id, Private_Dependents (T));
5646 -- If the subtype name denotes an incomplete type an error
5647 -- was already reported by Process_Subtype.
5650 Set_Etype (Id, Any_Type);
5654 raise Program_Error;
5658 if Etype (Id) = Any_Type then
5662 -- Some common processing on all types
5664 Set_Size_Info (Id, T);
5665 Set_First_Rep_Item (Id, First_Rep_Item (T));
5667 -- If the parent type is a generic actual, so is the subtype. This may
5668 -- happen in a nested instance. Why Comes_From_Source test???
5670 if not Comes_From_Source (N) then
5671 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5674 -- If this is a subtype declaration for an actual in an instance,
5675 -- inherit static and dynamic predicates if any.
5677 -- If declaration has no aspect specifications, inherit predicate
5678 -- info as well. Unclear how to handle the case of both specified
5679 -- and inherited predicates ??? Other inherited aspects, such as
5680 -- invariants, should be OK, but the combination with later pragmas
5681 -- may also require special merging.
5683 if Has_Predicates (T)
5684 and then Present (Predicate_Function (T))
5686 ((In_Instance and then not Comes_From_Source (N))
5687 or else No (Aspect_Specifications (N)))
5689 Set_Subprograms_For_Type (Id, Subprograms_For_Type (T));
5691 if Has_Static_Predicate (T) then
5692 Set_Has_Static_Predicate (Id);
5693 Set_Static_Discrete_Predicate (Id, Static_Discrete_Predicate (T));
5697 -- Remaining processing depends on characteristics of base type
5701 Set_Is_Immediately_Visible (Id, True);
5702 Set_Depends_On_Private (Id, Has_Private_Component (T));
5703 Set_Is_Descendant_Of_Address (Id, Is_Descendant_Of_Address (T));
5705 if Is_Interface (T) then
5706 Set_Is_Interface (Id);
5709 if Present (Generic_Parent_Type (N))
5711 (Nkind (Parent (Generic_Parent_Type (N))) /=
5712 N_Formal_Type_Declaration
5713 or else Nkind (Formal_Type_Definition
5714 (Parent (Generic_Parent_Type (N)))) /=
5715 N_Formal_Private_Type_Definition)
5717 if Is_Tagged_Type (Id) then
5719 -- If this is a generic actual subtype for a synchronized type,
5720 -- the primitive operations are those of the corresponding record
5721 -- for which there is a separate subtype declaration.
5723 if Is_Concurrent_Type (Id) then
5725 elsif Is_Class_Wide_Type (Id) then
5726 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5728 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5731 elsif Scope (Etype (Id)) /= Standard_Standard then
5732 Derive_Subprograms (Generic_Parent_Type (N), Id);
5736 if Is_Private_Type (T) and then Present (Full_View (T)) then
5737 Conditional_Delay (Id, Full_View (T));
5739 -- The subtypes of components or subcomponents of protected types
5740 -- do not need freeze nodes, which would otherwise appear in the
5741 -- wrong scope (before the freeze node for the protected type). The
5742 -- proper subtypes are those of the subcomponents of the corresponding
5745 elsif Ekind (Scope (Id)) /= E_Protected_Type
5746 and then Present (Scope (Scope (Id))) -- error defense
5747 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5749 Conditional_Delay (Id, T);
5752 -- If we have a subtype of an incomplete type whose full type is a
5753 -- derived numeric type, we need to have a freeze node for the subtype.
5754 -- Otherwise gigi will complain while computing the (static) bounds of
5758 and then Is_Elementary_Type (Id)
5759 and then Etype (Id) /= Id
5762 Partial : constant Entity_Id :=
5763 Incomplete_Or_Partial_View (First_Subtype (Id));
5765 if Present (Partial)
5766 and then Ekind (Partial) = E_Incomplete_Type
5768 Set_Has_Delayed_Freeze (Id);
5773 -- Check that Constraint_Error is raised for a scalar subtype indication
5774 -- when the lower or upper bound of a non-null range lies outside the
5775 -- range of the type mark.
5777 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5778 if Is_Scalar_Type (Etype (Id))
5779 and then Scalar_Range (Id) /=
5781 (Etype (Subtype_Mark (Subtype_Indication (N))))
5785 Etype (Subtype_Mark (Subtype_Indication (N))));
5787 -- In the array case, check compatibility for each index
5789 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5791 -- This really should be a subprogram that finds the indications
5795 Subt_Index : Node_Id := First_Index (Id);
5796 Target_Index : Node_Id :=
5798 (Subtype_Mark (Subtype_Indication (N))));
5799 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5802 while Present (Subt_Index) loop
5803 if ((Nkind (Subt_Index) = N_Identifier
5804 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5805 or else Nkind (Subt_Index) = N_Subtype_Indication)
5807 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5810 Target_Typ : constant Entity_Id :=
5811 Etype (Target_Index);
5815 (Scalar_Range (Etype (Subt_Index)),
5818 Defining_Identifier (N));
5820 -- Reset Has_Dynamic_Range_Check on the subtype to
5821 -- prevent elision of the index check due to a dynamic
5822 -- check generated for a preceding index (needed since
5823 -- Insert_Range_Checks tries to avoid generating
5824 -- redundant checks on a given declaration).
5826 Set_Has_Dynamic_Range_Check (N, False);
5832 Sloc (Defining_Identifier (N)));
5834 -- Record whether this index involved a dynamic check
5837 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5841 Next_Index (Subt_Index);
5842 Next_Index (Target_Index);
5845 -- Finally, mark whether the subtype involves dynamic checks
5847 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5852 Set_Optimize_Alignment_Flags (Id);
5853 Check_Eliminated (Id);
5856 if Has_Aspects (N) then
5857 Analyze_Aspect_Specifications (N, Id);
5860 Analyze_Dimension (N);
5862 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5863 -- indications on composite types where the constraints are dynamic.
5864 -- Note that object declarations and aggregates generate implicit
5865 -- subtype declarations, which this covers. One special case is that the
5866 -- implicitly generated "=" for discriminated types includes an
5867 -- offending subtype declaration, which is harmless, so we ignore it
5870 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5872 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5874 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5875 and then not (Is_Internal (Id)
5876 and then Is_TSS (Scope (Id),
5877 TSS_Composite_Equality))
5878 and then not Within_Init_Proc
5879 and then not All_Composite_Constraints_Static (Cstr)
5881 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5885 end Analyze_Subtype_Declaration;
5887 --------------------------------
5888 -- Analyze_Subtype_Indication --
5889 --------------------------------
5891 procedure Analyze_Subtype_Indication (N : Node_Id) is
5892 T : constant Entity_Id := Subtype_Mark (N);
5893 R : constant Node_Id := Range_Expression (Constraint (N));
5900 Set_Etype (N, Etype (R));
5901 Resolve (R, Entity (T));
5903 Set_Error_Posted (R);
5904 Set_Error_Posted (T);
5906 end Analyze_Subtype_Indication;
5908 --------------------------
5909 -- Analyze_Variant_Part --
5910 --------------------------
5912 procedure Analyze_Variant_Part (N : Node_Id) is
5913 Discr_Name : Node_Id;
5914 Discr_Type : Entity_Id;
5916 procedure Process_Variant (A : Node_Id);
5917 -- Analyze declarations for a single variant
5919 package Analyze_Variant_Choices is
5920 new Generic_Analyze_Choices (Process_Variant);
5921 use Analyze_Variant_Choices;
5923 ---------------------
5924 -- Process_Variant --
5925 ---------------------
5927 procedure Process_Variant (A : Node_Id) is
5928 CL : constant Node_Id := Component_List (A);
5930 if not Null_Present (CL) then
5931 Analyze_Declarations (Component_Items (CL));
5933 if Present (Variant_Part (CL)) then
5934 Analyze (Variant_Part (CL));
5937 end Process_Variant;
5939 -- Start of processing for Analyze_Variant_Part
5942 Discr_Name := Name (N);
5943 Analyze (Discr_Name);
5945 -- If Discr_Name bad, get out (prevent cascaded errors)
5947 if Etype (Discr_Name) = Any_Type then
5951 -- Check invalid discriminant in variant part
5953 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5954 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5957 Discr_Type := Etype (Entity (Discr_Name));
5959 if not Is_Discrete_Type (Discr_Type) then
5961 ("discriminant in a variant part must be of a discrete type",
5966 -- Now analyze the choices, which also analyzes the declarations that
5967 -- are associated with each choice.
5969 Analyze_Choices (Variants (N), Discr_Type);
5971 -- Note: we used to instantiate and call Check_Choices here to check
5972 -- that the choices covered the discriminant, but it's too early to do
5973 -- that because of statically predicated subtypes, whose analysis may
5974 -- be deferred to their freeze point which may be as late as the freeze
5975 -- point of the containing record. So this call is now to be found in
5976 -- Freeze_Record_Declaration.
5978 end Analyze_Variant_Part;
5980 ----------------------------
5981 -- Array_Type_Declaration --
5982 ----------------------------
5984 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5985 Component_Def : constant Node_Id := Component_Definition (Def);
5986 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5987 P : constant Node_Id := Parent (Def);
5988 Element_Type : Entity_Id;
5989 Implicit_Base : Entity_Id;
5993 Related_Id : Entity_Id := Empty;
5996 if Nkind (Def) = N_Constrained_Array_Definition then
5997 Index := First (Discrete_Subtype_Definitions (Def));
5999 Index := First (Subtype_Marks (Def));
6002 -- Find proper names for the implicit types which may be public. In case
6003 -- of anonymous arrays we use the name of the first object of that type
6007 Related_Id := Defining_Identifier (P);
6013 while Present (Index) loop
6016 -- Test for odd case of trying to index a type by the type itself
6018 if Is_Entity_Name (Index) and then Entity (Index) = T then
6019 Error_Msg_N ("type& cannot be indexed by itself", Index);
6020 Set_Entity (Index, Standard_Boolean);
6021 Set_Etype (Index, Standard_Boolean);
6024 -- Check SPARK restriction requiring a subtype mark
6026 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
6027 Check_SPARK_05_Restriction ("subtype mark required", Index);
6030 -- Add a subtype declaration for each index of private array type
6031 -- declaration whose etype is also private. For example:
6034 -- type Index is private;
6036 -- type Table is array (Index) of ...
6039 -- This is currently required by the expander for the internally
6040 -- generated equality subprogram of records with variant parts in
6041 -- which the etype of some component is such private type.
6043 if Ekind (Current_Scope) = E_Package
6044 and then In_Private_Part (Current_Scope)
6045 and then Has_Private_Declaration (Etype (Index))
6048 Loc : constant Source_Ptr := Sloc (Def);
6053 New_E := Make_Temporary (Loc, 'T');
6054 Set_Is_Internal (New_E);
6057 Make_Subtype_Declaration (Loc,
6058 Defining_Identifier => New_E,
6059 Subtype_Indication =>
6060 New_Occurrence_Of (Etype (Index), Loc));
6062 Insert_Before (Parent (Def), Decl);
6064 Set_Etype (Index, New_E);
6066 -- If the index is a range or a subtype indication it carries
6067 -- no entity. Example:
6070 -- type T is private;
6072 -- type T is new Natural;
6073 -- Table : array (T(1) .. T(10)) of Boolean;
6076 -- Otherwise the type of the reference is its entity.
6078 if Is_Entity_Name (Index) then
6079 Set_Entity (Index, New_E);
6084 Make_Index (Index, P, Related_Id, Nb_Index);
6086 -- Check error of subtype with predicate for index type
6088 Bad_Predicated_Subtype_Use
6089 ("subtype& has predicate, not allowed as index subtype",
6090 Index, Etype (Index));
6092 -- Move to next index
6095 Nb_Index := Nb_Index + 1;
6098 -- Process subtype indication if one is present
6100 if Present (Component_Typ) then
6101 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
6103 Set_Etype (Component_Typ, Element_Type);
6105 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
6106 Check_SPARK_05_Restriction
6107 ("subtype mark required", Component_Typ);
6110 -- Ada 2005 (AI-230): Access Definition case
6112 else pragma Assert (Present (Access_Definition (Component_Def)));
6114 -- Indicate that the anonymous access type is created by the
6115 -- array type declaration.
6117 Element_Type := Access_Definition
6119 N => Access_Definition (Component_Def));
6120 Set_Is_Local_Anonymous_Access (Element_Type);
6122 -- Propagate the parent. This field is needed if we have to generate
6123 -- the master_id associated with an anonymous access to task type
6124 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
6126 Set_Parent (Element_Type, Parent (T));
6128 -- Ada 2005 (AI-230): In case of components that are anonymous access
6129 -- types the level of accessibility depends on the enclosing type
6132 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
6134 -- Ada 2005 (AI-254)
6137 CD : constant Node_Id :=
6138 Access_To_Subprogram_Definition
6139 (Access_Definition (Component_Def));
6141 if Present (CD) and then Protected_Present (CD) then
6143 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
6148 -- Constrained array case
6151 T := Create_Itype (E_Void, P, Related_Id, 'T');
6154 if Nkind (Def) = N_Constrained_Array_Definition then
6156 -- Establish Implicit_Base as unconstrained base type
6158 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
6160 Set_Etype (Implicit_Base, Implicit_Base);
6161 Set_Scope (Implicit_Base, Current_Scope);
6162 Set_Has_Delayed_Freeze (Implicit_Base);
6163 Set_Default_SSO (Implicit_Base);
6165 -- The constrained array type is a subtype of the unconstrained one
6167 Set_Ekind (T, E_Array_Subtype);
6168 Init_Size_Align (T);
6169 Set_Etype (T, Implicit_Base);
6170 Set_Scope (T, Current_Scope);
6171 Set_Is_Constrained (T);
6173 First (Discrete_Subtype_Definitions (Def)));
6174 Set_Has_Delayed_Freeze (T);
6176 -- Complete setup of implicit base type
6178 Set_Component_Size (Implicit_Base, Uint_0);
6179 Set_Component_Type (Implicit_Base, Element_Type);
6180 Set_Finalize_Storage_Only
6182 Finalize_Storage_Only (Element_Type));
6183 Set_First_Index (Implicit_Base, First_Index (T));
6184 Set_Has_Controlled_Component
6186 Has_Controlled_Component (Element_Type)
6187 or else Is_Controlled (Element_Type));
6188 Set_Packed_Array_Impl_Type
6189 (Implicit_Base, Empty);
6191 Propagate_Concurrent_Flags (Implicit_Base, Element_Type);
6193 -- Unconstrained array case
6196 Set_Ekind (T, E_Array_Type);
6197 Init_Size_Align (T);
6199 Set_Scope (T, Current_Scope);
6200 Set_Component_Size (T, Uint_0);
6201 Set_Is_Constrained (T, False);
6202 Set_First_Index (T, First (Subtype_Marks (Def)));
6203 Set_Has_Delayed_Freeze (T, True);
6204 Propagate_Concurrent_Flags (T, Element_Type);
6205 Set_Has_Controlled_Component (T, Has_Controlled_Component
6208 Is_Controlled (Element_Type));
6209 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
6211 Set_Default_SSO (T);
6214 -- Common attributes for both cases
6216 Set_Component_Type (Base_Type (T), Element_Type);
6217 Set_Packed_Array_Impl_Type (T, Empty);
6219 if Aliased_Present (Component_Definition (Def)) then
6220 Check_SPARK_05_Restriction
6221 ("aliased is not allowed", Component_Definition (Def));
6222 Set_Has_Aliased_Components (Etype (T));
6225 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
6226 -- array type to ensure that objects of this type are initialized.
6228 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
6229 Set_Can_Never_Be_Null (T);
6231 if Null_Exclusion_Present (Component_Definition (Def))
6233 -- No need to check itypes because in their case this check was
6234 -- done at their point of creation
6236 and then not Is_Itype (Element_Type)
6239 ("`NOT NULL` not allowed (null already excluded)",
6240 Subtype_Indication (Component_Definition (Def)));
6244 Priv := Private_Component (Element_Type);
6246 if Present (Priv) then
6248 -- Check for circular definitions
6250 if Priv = Any_Type then
6251 Set_Component_Type (Etype (T), Any_Type);
6253 -- There is a gap in the visibility of operations on the composite
6254 -- type only if the component type is defined in a different scope.
6256 elsif Scope (Priv) = Current_Scope then
6259 elsif Is_Limited_Type (Priv) then
6260 Set_Is_Limited_Composite (Etype (T));
6261 Set_Is_Limited_Composite (T);
6263 Set_Is_Private_Composite (Etype (T));
6264 Set_Is_Private_Composite (T);
6268 -- A syntax error in the declaration itself may lead to an empty index
6269 -- list, in which case do a minimal patch.
6271 if No (First_Index (T)) then
6272 Error_Msg_N ("missing index definition in array type declaration", T);
6275 Indexes : constant List_Id :=
6276 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
6278 Set_Discrete_Subtype_Definitions (Def, Indexes);
6279 Set_First_Index (T, First (Indexes));
6284 -- Create a concatenation operator for the new type. Internal array
6285 -- types created for packed entities do not need such, they are
6286 -- compatible with the user-defined type.
6288 if Number_Dimensions (T) = 1
6289 and then not Is_Packed_Array_Impl_Type (T)
6291 New_Concatenation_Op (T);
6294 -- In the case of an unconstrained array the parser has already verified
6295 -- that all the indexes are unconstrained but we still need to make sure
6296 -- that the element type is constrained.
6298 if not Is_Definite_Subtype (Element_Type) then
6300 ("unconstrained element type in array declaration",
6301 Subtype_Indication (Component_Def));
6303 elsif Is_Abstract_Type (Element_Type) then
6305 ("the type of a component cannot be abstract",
6306 Subtype_Indication (Component_Def));
6309 -- There may be an invariant declared for the component type, but
6310 -- the construction of the component invariant checking procedure
6311 -- takes place during expansion.
6312 end Array_Type_Declaration;
6314 ------------------------------------------------------
6315 -- Replace_Anonymous_Access_To_Protected_Subprogram --
6316 ------------------------------------------------------
6318 function Replace_Anonymous_Access_To_Protected_Subprogram
6319 (N : Node_Id) return Entity_Id
6321 Loc : constant Source_Ptr := Sloc (N);
6323 Curr_Scope : constant Scope_Stack_Entry :=
6324 Scope_Stack.Table (Scope_Stack.Last);
6326 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
6329 -- Access definition in declaration
6332 -- Object definition or formal definition with an access definition
6335 -- Declaration of anonymous access to subprogram type
6338 -- Original specification in access to subprogram
6343 Set_Is_Internal (Anon);
6346 when N_Constrained_Array_Definition
6347 | N_Component_Declaration
6348 | N_Unconstrained_Array_Definition
6350 Comp := Component_Definition (N);
6351 Acc := Access_Definition (Comp);
6353 when N_Discriminant_Specification =>
6354 Comp := Discriminant_Type (N);
6357 when N_Parameter_Specification =>
6358 Comp := Parameter_Type (N);
6361 when N_Access_Function_Definition =>
6362 Comp := Result_Definition (N);
6365 when N_Object_Declaration =>
6366 Comp := Object_Definition (N);
6369 when N_Function_Specification =>
6370 Comp := Result_Definition (N);
6374 raise Program_Error;
6377 Spec := Access_To_Subprogram_Definition (Acc);
6380 Make_Full_Type_Declaration (Loc,
6381 Defining_Identifier => Anon,
6382 Type_Definition => Copy_Separate_Tree (Spec));
6384 Mark_Rewrite_Insertion (Decl);
6386 -- In ASIS mode, analyze the profile on the original node, because
6387 -- the separate copy does not provide enough links to recover the
6388 -- original tree. Analysis is limited to type annotations, within
6389 -- a temporary scope that serves as an anonymous subprogram to collect
6390 -- otherwise useless temporaries and itypes.
6394 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
6397 if Nkind (Spec) = N_Access_Function_Definition then
6398 Set_Ekind (Typ, E_Function);
6400 Set_Ekind (Typ, E_Procedure);
6403 Set_Parent (Typ, N);
6404 Set_Scope (Typ, Current_Scope);
6407 -- Nothing to do if procedure is parameterless
6409 if Present (Parameter_Specifications (Spec)) then
6410 Process_Formals (Parameter_Specifications (Spec), Spec);
6413 if Nkind (Spec) = N_Access_Function_Definition then
6415 Def : constant Node_Id := Result_Definition (Spec);
6418 -- The result might itself be an anonymous access type, so
6421 if Nkind (Def) = N_Access_Definition then
6422 if Present (Access_To_Subprogram_Definition (Def)) then
6425 Replace_Anonymous_Access_To_Protected_Subprogram
6428 Find_Type (Subtype_Mark (Def));
6441 -- Insert the new declaration in the nearest enclosing scope. If the
6442 -- parent is a body and N is its return type, the declaration belongs
6443 -- in the enclosing scope. Likewise if N is the type of a parameter.
6447 if Nkind (N) = N_Function_Specification
6448 and then Nkind (P) = N_Subprogram_Body
6451 elsif Nkind (N) = N_Parameter_Specification
6452 and then Nkind (P) in N_Subprogram_Specification
6453 and then Nkind (Parent (P)) = N_Subprogram_Body
6455 P := Parent (Parent (P));
6458 while Present (P) and then not Has_Declarations (P) loop
6462 pragma Assert (Present (P));
6464 if Nkind (P) = N_Package_Specification then
6465 Prepend (Decl, Visible_Declarations (P));
6467 Prepend (Decl, Declarations (P));
6470 -- Replace the anonymous type with an occurrence of the new declaration.
6471 -- In all cases the rewritten node does not have the null-exclusion
6472 -- attribute because (if present) it was already inherited by the
6473 -- anonymous entity (Anon). Thus, in case of components we do not
6474 -- inherit this attribute.
6476 if Nkind (N) = N_Parameter_Specification then
6477 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6478 Set_Etype (Defining_Identifier (N), Anon);
6479 Set_Null_Exclusion_Present (N, False);
6481 elsif Nkind (N) = N_Object_Declaration then
6482 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6483 Set_Etype (Defining_Identifier (N), Anon);
6485 elsif Nkind (N) = N_Access_Function_Definition then
6486 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6488 elsif Nkind (N) = N_Function_Specification then
6489 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6490 Set_Etype (Defining_Unit_Name (N), Anon);
6494 Make_Component_Definition (Loc,
6495 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
6498 Mark_Rewrite_Insertion (Comp);
6500 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
6501 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
6502 and then not Is_Type (Current_Scope))
6505 -- Declaration can be analyzed in the current scope.
6510 -- Temporarily remove the current scope (record or subprogram) from
6511 -- the stack to add the new declarations to the enclosing scope.
6512 -- The anonymous entity is an Itype with the proper attributes.
6514 Scope_Stack.Decrement_Last;
6516 Set_Is_Itype (Anon);
6517 Set_Associated_Node_For_Itype (Anon, N);
6518 Scope_Stack.Append (Curr_Scope);
6521 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
6522 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
6524 end Replace_Anonymous_Access_To_Protected_Subprogram;
6526 -------------------------------
6527 -- Build_Derived_Access_Type --
6528 -------------------------------
6530 procedure Build_Derived_Access_Type
6532 Parent_Type : Entity_Id;
6533 Derived_Type : Entity_Id)
6535 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
6537 Desig_Type : Entity_Id;
6539 Discr_Con_Elist : Elist_Id;
6540 Discr_Con_El : Elmt_Id;
6544 -- Set the designated type so it is available in case this is an access
6545 -- to a self-referential type, e.g. a standard list type with a next
6546 -- pointer. Will be reset after subtype is built.
6548 Set_Directly_Designated_Type
6549 (Derived_Type, Designated_Type (Parent_Type));
6551 Subt := Process_Subtype (S, N);
6553 if Nkind (S) /= N_Subtype_Indication
6554 and then Subt /= Base_Type (Subt)
6556 Set_Ekind (Derived_Type, E_Access_Subtype);
6559 if Ekind (Derived_Type) = E_Access_Subtype then
6561 Pbase : constant Entity_Id := Base_Type (Parent_Type);
6562 Ibase : constant Entity_Id :=
6563 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
6564 Svg_Chars : constant Name_Id := Chars (Ibase);
6565 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
6568 Copy_Node (Pbase, Ibase);
6570 -- Restore Itype status after Copy_Node
6572 Set_Is_Itype (Ibase);
6573 Set_Associated_Node_For_Itype (Ibase, N);
6575 Set_Chars (Ibase, Svg_Chars);
6576 Set_Next_Entity (Ibase, Svg_Next_E);
6577 Set_Sloc (Ibase, Sloc (Derived_Type));
6578 Set_Scope (Ibase, Scope (Derived_Type));
6579 Set_Freeze_Node (Ibase, Empty);
6580 Set_Is_Frozen (Ibase, False);
6581 Set_Comes_From_Source (Ibase, False);
6582 Set_Is_First_Subtype (Ibase, False);
6584 Set_Etype (Ibase, Pbase);
6585 Set_Etype (Derived_Type, Ibase);
6589 Set_Directly_Designated_Type
6590 (Derived_Type, Designated_Type (Subt));
6592 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
6593 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
6594 Set_Size_Info (Derived_Type, Parent_Type);
6595 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
6596 Set_Depends_On_Private (Derived_Type,
6597 Has_Private_Component (Derived_Type));
6598 Conditional_Delay (Derived_Type, Subt);
6600 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
6601 -- that it is not redundant.
6603 if Null_Exclusion_Present (Type_Definition (N)) then
6604 Set_Can_Never_Be_Null (Derived_Type);
6606 elsif Can_Never_Be_Null (Parent_Type) then
6607 Set_Can_Never_Be_Null (Derived_Type);
6610 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6611 -- the root type for this information.
6613 -- Apply range checks to discriminants for derived record case
6614 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6616 Desig_Type := Designated_Type (Derived_Type);
6618 if Is_Composite_Type (Desig_Type)
6619 and then (not Is_Array_Type (Desig_Type))
6620 and then Has_Discriminants (Desig_Type)
6621 and then Base_Type (Desig_Type) /= Desig_Type
6623 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6624 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6626 Discr := First_Discriminant (Base_Type (Desig_Type));
6627 while Present (Discr_Con_El) loop
6628 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6629 Next_Elmt (Discr_Con_El);
6630 Next_Discriminant (Discr);
6633 end Build_Derived_Access_Type;
6635 ------------------------------
6636 -- Build_Derived_Array_Type --
6637 ------------------------------
6639 procedure Build_Derived_Array_Type
6641 Parent_Type : Entity_Id;
6642 Derived_Type : Entity_Id)
6644 Loc : constant Source_Ptr := Sloc (N);
6645 Tdef : constant Node_Id := Type_Definition (N);
6646 Indic : constant Node_Id := Subtype_Indication (Tdef);
6647 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6648 Implicit_Base : Entity_Id;
6649 New_Indic : Node_Id;
6651 procedure Make_Implicit_Base;
6652 -- If the parent subtype is constrained, the derived type is a subtype
6653 -- of an implicit base type derived from the parent base.
6655 ------------------------
6656 -- Make_Implicit_Base --
6657 ------------------------
6659 procedure Make_Implicit_Base is
6662 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6664 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6665 Set_Etype (Implicit_Base, Parent_Base);
6667 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6668 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6670 Set_Has_Delayed_Freeze (Implicit_Base, True);
6671 end Make_Implicit_Base;
6673 -- Start of processing for Build_Derived_Array_Type
6676 if not Is_Constrained (Parent_Type) then
6677 if Nkind (Indic) /= N_Subtype_Indication then
6678 Set_Ekind (Derived_Type, E_Array_Type);
6680 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6681 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6683 Set_Has_Delayed_Freeze (Derived_Type, True);
6687 Set_Etype (Derived_Type, Implicit_Base);
6690 Make_Subtype_Declaration (Loc,
6691 Defining_Identifier => Derived_Type,
6692 Subtype_Indication =>
6693 Make_Subtype_Indication (Loc,
6694 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6695 Constraint => Constraint (Indic)));
6697 Rewrite (N, New_Indic);
6702 if Nkind (Indic) /= N_Subtype_Indication then
6705 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6706 Set_Etype (Derived_Type, Implicit_Base);
6707 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6710 Error_Msg_N ("illegal constraint on constrained type", Indic);
6714 -- If parent type is not a derived type itself, and is declared in
6715 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6716 -- the new type's concatenation operator since Derive_Subprograms
6717 -- will not inherit the parent's operator. If the parent type is
6718 -- unconstrained, the operator is of the unconstrained base type.
6720 if Number_Dimensions (Parent_Type) = 1
6721 and then not Is_Limited_Type (Parent_Type)
6722 and then not Is_Derived_Type (Parent_Type)
6723 and then not Is_Package_Or_Generic_Package
6724 (Scope (Base_Type (Parent_Type)))
6726 if not Is_Constrained (Parent_Type)
6727 and then Is_Constrained (Derived_Type)
6729 New_Concatenation_Op (Implicit_Base);
6731 New_Concatenation_Op (Derived_Type);
6734 end Build_Derived_Array_Type;
6736 -----------------------------------
6737 -- Build_Derived_Concurrent_Type --
6738 -----------------------------------
6740 procedure Build_Derived_Concurrent_Type
6742 Parent_Type : Entity_Id;
6743 Derived_Type : Entity_Id)
6745 Loc : constant Source_Ptr := Sloc (N);
6747 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6748 Corr_Decl : Node_Id;
6749 Corr_Decl_Needed : Boolean;
6750 -- If the derived type has fewer discriminants than its parent, the
6751 -- corresponding record is also a derived type, in order to account for
6752 -- the bound discriminants. We create a full type declaration for it in
6755 Constraint_Present : constant Boolean :=
6756 Nkind (Subtype_Indication (Type_Definition (N))) =
6757 N_Subtype_Indication;
6759 D_Constraint : Node_Id;
6760 New_Constraint : Elist_Id;
6761 Old_Disc : Entity_Id;
6762 New_Disc : Entity_Id;
6766 Set_Stored_Constraint (Derived_Type, No_Elist);
6767 Corr_Decl_Needed := False;
6770 if Present (Discriminant_Specifications (N))
6771 and then Constraint_Present
6773 Old_Disc := First_Discriminant (Parent_Type);
6774 New_Disc := First (Discriminant_Specifications (N));
6775 while Present (New_Disc) and then Present (Old_Disc) loop
6776 Next_Discriminant (Old_Disc);
6781 if Present (Old_Disc) and then Expander_Active then
6783 -- The new type has fewer discriminants, so we need to create a new
6784 -- corresponding record, which is derived from the corresponding
6785 -- record of the parent, and has a stored constraint that captures
6786 -- the values of the discriminant constraints. The corresponding
6787 -- record is needed only if expander is active and code generation is
6790 -- The type declaration for the derived corresponding record has the
6791 -- same discriminant part and constraints as the current declaration.
6792 -- Copy the unanalyzed tree to build declaration.
6794 Corr_Decl_Needed := True;
6795 New_N := Copy_Separate_Tree (N);
6798 Make_Full_Type_Declaration (Loc,
6799 Defining_Identifier => Corr_Record,
6800 Discriminant_Specifications =>
6801 Discriminant_Specifications (New_N),
6803 Make_Derived_Type_Definition (Loc,
6804 Subtype_Indication =>
6805 Make_Subtype_Indication (Loc,
6808 (Corresponding_Record_Type (Parent_Type), Loc),
6811 (Subtype_Indication (Type_Definition (New_N))))));
6814 -- Copy Storage_Size and Relative_Deadline variables if task case
6816 if Is_Task_Type (Parent_Type) then
6817 Set_Storage_Size_Variable (Derived_Type,
6818 Storage_Size_Variable (Parent_Type));
6819 Set_Relative_Deadline_Variable (Derived_Type,
6820 Relative_Deadline_Variable (Parent_Type));
6823 if Present (Discriminant_Specifications (N)) then
6824 Push_Scope (Derived_Type);
6825 Check_Or_Process_Discriminants (N, Derived_Type);
6827 if Constraint_Present then
6829 Expand_To_Stored_Constraint
6831 Build_Discriminant_Constraints
6833 Subtype_Indication (Type_Definition (N)), True));
6838 elsif Constraint_Present then
6840 -- Build constrained subtype, copying the constraint, and derive
6841 -- from it to create a derived constrained type.
6844 Loc : constant Source_Ptr := Sloc (N);
6845 Anon : constant Entity_Id :=
6846 Make_Defining_Identifier (Loc,
6847 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6852 Make_Subtype_Declaration (Loc,
6853 Defining_Identifier => Anon,
6854 Subtype_Indication =>
6855 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6856 Insert_Before (N, Decl);
6859 Rewrite (Subtype_Indication (Type_Definition (N)),
6860 New_Occurrence_Of (Anon, Loc));
6861 Set_Analyzed (Derived_Type, False);
6867 -- By default, operations and private data are inherited from parent.
6868 -- However, in the presence of bound discriminants, a new corresponding
6869 -- record will be created, see below.
6871 Set_Has_Discriminants
6872 (Derived_Type, Has_Discriminants (Parent_Type));
6873 Set_Corresponding_Record_Type
6874 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6876 -- Is_Constrained is set according the parent subtype, but is set to
6877 -- False if the derived type is declared with new discriminants.
6881 (Is_Constrained (Parent_Type) or else Constraint_Present)
6882 and then not Present (Discriminant_Specifications (N)));
6884 if Constraint_Present then
6885 if not Has_Discriminants (Parent_Type) then
6886 Error_Msg_N ("untagged parent must have discriminants", N);
6888 elsif Present (Discriminant_Specifications (N)) then
6890 -- Verify that new discriminants are used to constrain old ones
6895 (Constraint (Subtype_Indication (Type_Definition (N)))));
6897 Old_Disc := First_Discriminant (Parent_Type);
6899 while Present (D_Constraint) loop
6900 if Nkind (D_Constraint) /= N_Discriminant_Association then
6902 -- Positional constraint. If it is a reference to a new
6903 -- discriminant, it constrains the corresponding old one.
6905 if Nkind (D_Constraint) = N_Identifier then
6906 New_Disc := First_Discriminant (Derived_Type);
6907 while Present (New_Disc) loop
6908 exit when Chars (New_Disc) = Chars (D_Constraint);
6909 Next_Discriminant (New_Disc);
6912 if Present (New_Disc) then
6913 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6917 Next_Discriminant (Old_Disc);
6919 -- if this is a named constraint, search by name for the old
6920 -- discriminants constrained by the new one.
6922 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6924 -- Find new discriminant with that name
6926 New_Disc := First_Discriminant (Derived_Type);
6927 while Present (New_Disc) loop
6929 Chars (New_Disc) = Chars (Expression (D_Constraint));
6930 Next_Discriminant (New_Disc);
6933 if Present (New_Disc) then
6935 -- Verify that new discriminant renames some discriminant
6936 -- of the parent type, and associate the new discriminant
6937 -- with one or more old ones that it renames.
6943 Selector := First (Selector_Names (D_Constraint));
6944 while Present (Selector) loop
6945 Old_Disc := First_Discriminant (Parent_Type);
6946 while Present (Old_Disc) loop
6947 exit when Chars (Old_Disc) = Chars (Selector);
6948 Next_Discriminant (Old_Disc);
6951 if Present (Old_Disc) then
6952 Set_Corresponding_Discriminant
6953 (New_Disc, Old_Disc);
6962 Next (D_Constraint);
6965 New_Disc := First_Discriminant (Derived_Type);
6966 while Present (New_Disc) loop
6967 if No (Corresponding_Discriminant (New_Disc)) then
6969 ("new discriminant& must constrain old one", N, New_Disc);
6972 Subtypes_Statically_Compatible
6974 Etype (Corresponding_Discriminant (New_Disc)))
6977 ("& not statically compatible with parent discriminant",
6981 Next_Discriminant (New_Disc);
6985 elsif Present (Discriminant_Specifications (N)) then
6987 ("missing discriminant constraint in untagged derivation", N);
6990 -- The entity chain of the derived type includes the new discriminants
6991 -- but shares operations with the parent.
6993 if Present (Discriminant_Specifications (N)) then
6994 Old_Disc := First_Discriminant (Parent_Type);
6995 while Present (Old_Disc) loop
6996 if No (Next_Entity (Old_Disc))
6997 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
7000 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
7004 Next_Discriminant (Old_Disc);
7008 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
7009 if Has_Discriminants (Parent_Type) then
7010 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7011 Set_Discriminant_Constraint (
7012 Derived_Type, Discriminant_Constraint (Parent_Type));
7016 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
7018 Set_Has_Completion (Derived_Type);
7020 if Corr_Decl_Needed then
7021 Set_Stored_Constraint (Derived_Type, New_Constraint);
7022 Insert_After (N, Corr_Decl);
7023 Analyze (Corr_Decl);
7024 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
7026 end Build_Derived_Concurrent_Type;
7028 ------------------------------------
7029 -- Build_Derived_Enumeration_Type --
7030 ------------------------------------
7032 procedure Build_Derived_Enumeration_Type
7034 Parent_Type : Entity_Id;
7035 Derived_Type : Entity_Id)
7037 Loc : constant Source_Ptr := Sloc (N);
7038 Def : constant Node_Id := Type_Definition (N);
7039 Indic : constant Node_Id := Subtype_Indication (Def);
7040 Implicit_Base : Entity_Id;
7041 Literal : Entity_Id;
7042 New_Lit : Entity_Id;
7043 Literals_List : List_Id;
7044 Type_Decl : Node_Id;
7046 Rang_Expr : Node_Id;
7049 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
7050 -- not have explicit literals lists we need to process types derived
7051 -- from them specially. This is handled by Derived_Standard_Character.
7052 -- If the parent type is a generic type, there are no literals either,
7053 -- and we construct the same skeletal representation as for the generic
7056 if Is_Standard_Character_Type (Parent_Type) then
7057 Derived_Standard_Character (N, Parent_Type, Derived_Type);
7059 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
7065 if Nkind (Indic) /= N_Subtype_Indication then
7067 Make_Attribute_Reference (Loc,
7068 Attribute_Name => Name_First,
7069 Prefix => New_Occurrence_Of (Derived_Type, Loc));
7070 Set_Etype (Lo, Derived_Type);
7073 Make_Attribute_Reference (Loc,
7074 Attribute_Name => Name_Last,
7075 Prefix => New_Occurrence_Of (Derived_Type, Loc));
7076 Set_Etype (Hi, Derived_Type);
7078 Set_Scalar_Range (Derived_Type,
7084 -- Analyze subtype indication and verify compatibility
7085 -- with parent type.
7087 if Base_Type (Process_Subtype (Indic, N)) /=
7088 Base_Type (Parent_Type)
7091 ("illegal constraint for formal discrete type", N);
7097 -- If a constraint is present, analyze the bounds to catch
7098 -- premature usage of the derived literals.
7100 if Nkind (Indic) = N_Subtype_Indication
7101 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
7103 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
7104 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
7107 -- Introduce an implicit base type for the derived type even if there
7108 -- is no constraint attached to it, since this seems closer to the
7109 -- Ada semantics. Build a full type declaration tree for the derived
7110 -- type using the implicit base type as the defining identifier. The
7111 -- build a subtype declaration tree which applies the constraint (if
7112 -- any) have it replace the derived type declaration.
7114 Literal := First_Literal (Parent_Type);
7115 Literals_List := New_List;
7116 while Present (Literal)
7117 and then Ekind (Literal) = E_Enumeration_Literal
7119 -- Literals of the derived type have the same representation as
7120 -- those of the parent type, but this representation can be
7121 -- overridden by an explicit representation clause. Indicate
7122 -- that there is no explicit representation given yet. These
7123 -- derived literals are implicit operations of the new type,
7124 -- and can be overridden by explicit ones.
7126 if Nkind (Literal) = N_Defining_Character_Literal then
7128 Make_Defining_Character_Literal (Loc, Chars (Literal));
7130 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
7133 Set_Ekind (New_Lit, E_Enumeration_Literal);
7134 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
7135 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
7136 Set_Enumeration_Rep_Expr (New_Lit, Empty);
7137 Set_Alias (New_Lit, Literal);
7138 Set_Is_Known_Valid (New_Lit, True);
7140 Append (New_Lit, Literals_List);
7141 Next_Literal (Literal);
7145 Make_Defining_Identifier (Sloc (Derived_Type),
7146 Chars => New_External_Name (Chars (Derived_Type), 'B'));
7148 -- Indicate the proper nature of the derived type. This must be done
7149 -- before analysis of the literals, to recognize cases when a literal
7150 -- may be hidden by a previous explicit function definition (cf.
7153 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
7154 Set_Etype (Derived_Type, Implicit_Base);
7157 Make_Full_Type_Declaration (Loc,
7158 Defining_Identifier => Implicit_Base,
7159 Discriminant_Specifications => No_List,
7161 Make_Enumeration_Type_Definition (Loc, Literals_List));
7163 Mark_Rewrite_Insertion (Type_Decl);
7164 Insert_Before (N, Type_Decl);
7165 Analyze (Type_Decl);
7167 -- The anonymous base now has a full declaration, but this base
7168 -- is not a first subtype.
7170 Set_Is_First_Subtype (Implicit_Base, False);
7172 -- After the implicit base is analyzed its Etype needs to be changed
7173 -- to reflect the fact that it is derived from the parent type which
7174 -- was ignored during analysis. We also set the size at this point.
7176 Set_Etype (Implicit_Base, Parent_Type);
7178 Set_Size_Info (Implicit_Base, Parent_Type);
7179 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
7180 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
7182 -- Copy other flags from parent type
7184 Set_Has_Non_Standard_Rep
7185 (Implicit_Base, Has_Non_Standard_Rep
7187 Set_Has_Pragma_Ordered
7188 (Implicit_Base, Has_Pragma_Ordered
7190 Set_Has_Delayed_Freeze (Implicit_Base);
7192 -- Process the subtype indication including a validation check on the
7193 -- constraint, if any. If a constraint is given, its bounds must be
7194 -- implicitly converted to the new type.
7196 if Nkind (Indic) = N_Subtype_Indication then
7198 R : constant Node_Id :=
7199 Range_Expression (Constraint (Indic));
7202 if Nkind (R) = N_Range then
7203 Hi := Build_Scalar_Bound
7204 (High_Bound (R), Parent_Type, Implicit_Base);
7205 Lo := Build_Scalar_Bound
7206 (Low_Bound (R), Parent_Type, Implicit_Base);
7209 -- Constraint is a Range attribute. Replace with explicit
7210 -- mention of the bounds of the prefix, which must be a
7213 Analyze (Prefix (R));
7215 Convert_To (Implicit_Base,
7216 Make_Attribute_Reference (Loc,
7217 Attribute_Name => Name_Last,
7219 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
7222 Convert_To (Implicit_Base,
7223 Make_Attribute_Reference (Loc,
7224 Attribute_Name => Name_First,
7226 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
7233 (Type_High_Bound (Parent_Type),
7234 Parent_Type, Implicit_Base);
7237 (Type_Low_Bound (Parent_Type),
7238 Parent_Type, Implicit_Base);
7246 -- If we constructed a default range for the case where no range
7247 -- was given, then the expressions in the range must not freeze
7248 -- since they do not correspond to expressions in the source.
7249 -- However, if the type inherits predicates the expressions will
7250 -- be elaborated earlier and must freeze.
7252 if Nkind (Indic) /= N_Subtype_Indication
7253 and then not Has_Predicates (Derived_Type)
7255 Set_Must_Not_Freeze (Lo);
7256 Set_Must_Not_Freeze (Hi);
7257 Set_Must_Not_Freeze (Rang_Expr);
7261 Make_Subtype_Declaration (Loc,
7262 Defining_Identifier => Derived_Type,
7263 Subtype_Indication =>
7264 Make_Subtype_Indication (Loc,
7265 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
7267 Make_Range_Constraint (Loc,
7268 Range_Expression => Rang_Expr))));
7272 -- Propagate the aspects from the original type declaration to the
7273 -- declaration of the implicit base.
7275 Move_Aspects (From => Original_Node (N), To => Type_Decl);
7277 -- Apply a range check. Since this range expression doesn't have an
7278 -- Etype, we have to specifically pass the Source_Typ parameter. Is
7281 if Nkind (Indic) = N_Subtype_Indication then
7283 (Range_Expression (Constraint (Indic)), Parent_Type,
7284 Source_Typ => Entity (Subtype_Mark (Indic)));
7287 end Build_Derived_Enumeration_Type;
7289 --------------------------------
7290 -- Build_Derived_Numeric_Type --
7291 --------------------------------
7293 procedure Build_Derived_Numeric_Type
7295 Parent_Type : Entity_Id;
7296 Derived_Type : Entity_Id)
7298 Loc : constant Source_Ptr := Sloc (N);
7299 Tdef : constant Node_Id := Type_Definition (N);
7300 Indic : constant Node_Id := Subtype_Indication (Tdef);
7301 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7302 No_Constraint : constant Boolean := Nkind (Indic) /=
7303 N_Subtype_Indication;
7304 Implicit_Base : Entity_Id;
7310 -- Process the subtype indication including a validation check on
7311 -- the constraint if any.
7313 Discard_Node (Process_Subtype (Indic, N));
7315 -- Introduce an implicit base type for the derived type even if there
7316 -- is no constraint attached to it, since this seems closer to the Ada
7320 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
7322 Set_Etype (Implicit_Base, Parent_Base);
7323 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
7324 Set_Size_Info (Implicit_Base, Parent_Base);
7325 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
7326 Set_Parent (Implicit_Base, Parent (Derived_Type));
7327 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
7329 -- Set RM Size for discrete type or decimal fixed-point type
7330 -- Ordinary fixed-point is excluded, why???
7332 if Is_Discrete_Type (Parent_Base)
7333 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
7335 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
7338 Set_Has_Delayed_Freeze (Implicit_Base);
7340 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
7341 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
7343 Set_Scalar_Range (Implicit_Base,
7348 if Has_Infinities (Parent_Base) then
7349 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
7352 -- The Derived_Type, which is the entity of the declaration, is a
7353 -- subtype of the implicit base. Its Ekind is a subtype, even in the
7354 -- absence of an explicit constraint.
7356 Set_Etype (Derived_Type, Implicit_Base);
7358 -- If we did not have a constraint, then the Ekind is set from the
7359 -- parent type (otherwise Process_Subtype has set the bounds)
7361 if No_Constraint then
7362 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
7365 -- If we did not have a range constraint, then set the range from the
7366 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
7368 if No_Constraint or else not Has_Range_Constraint (Indic) then
7369 Set_Scalar_Range (Derived_Type,
7371 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
7372 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
7373 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7375 if Has_Infinities (Parent_Type) then
7376 Set_Includes_Infinities (Scalar_Range (Derived_Type));
7379 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
7382 Set_Is_Descendant_Of_Address (Derived_Type,
7383 Is_Descendant_Of_Address (Parent_Type));
7384 Set_Is_Descendant_Of_Address (Implicit_Base,
7385 Is_Descendant_Of_Address (Parent_Type));
7387 -- Set remaining type-specific fields, depending on numeric type
7389 if Is_Modular_Integer_Type (Parent_Type) then
7390 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
7392 Set_Non_Binary_Modulus
7393 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
7396 (Implicit_Base, Is_Known_Valid (Parent_Base));
7398 elsif Is_Floating_Point_Type (Parent_Type) then
7400 -- Digits of base type is always copied from the digits value of
7401 -- the parent base type, but the digits of the derived type will
7402 -- already have been set if there was a constraint present.
7404 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7405 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
7407 if No_Constraint then
7408 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
7411 elsif Is_Fixed_Point_Type (Parent_Type) then
7413 -- Small of base type and derived type are always copied from the
7414 -- parent base type, since smalls never change. The delta of the
7415 -- base type is also copied from the parent base type. However the
7416 -- delta of the derived type will have been set already if a
7417 -- constraint was present.
7419 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
7420 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
7421 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
7423 if No_Constraint then
7424 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
7427 -- The scale and machine radix in the decimal case are always
7428 -- copied from the parent base type.
7430 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
7431 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
7432 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
7434 Set_Machine_Radix_10
7435 (Derived_Type, Machine_Radix_10 (Parent_Base));
7436 Set_Machine_Radix_10
7437 (Implicit_Base, Machine_Radix_10 (Parent_Base));
7439 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7441 if No_Constraint then
7442 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
7445 -- the analysis of the subtype_indication sets the
7446 -- digits value of the derived type.
7453 if Is_Integer_Type (Parent_Type) then
7454 Set_Has_Shift_Operator
7455 (Implicit_Base, Has_Shift_Operator (Parent_Type));
7458 -- The type of the bounds is that of the parent type, and they
7459 -- must be converted to the derived type.
7461 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
7463 -- The implicit_base should be frozen when the derived type is frozen,
7464 -- but note that it is used in the conversions of the bounds. For fixed
7465 -- types we delay the determination of the bounds until the proper
7466 -- freezing point. For other numeric types this is rejected by GCC, for
7467 -- reasons that are currently unclear (???), so we choose to freeze the
7468 -- implicit base now. In the case of integers and floating point types
7469 -- this is harmless because subsequent representation clauses cannot
7470 -- affect anything, but it is still baffling that we cannot use the
7471 -- same mechanism for all derived numeric types.
7473 -- There is a further complication: actually some representation
7474 -- clauses can affect the implicit base type. For example, attribute
7475 -- definition clauses for stream-oriented attributes need to set the
7476 -- corresponding TSS entries on the base type, and this normally
7477 -- cannot be done after the base type is frozen, so the circuitry in
7478 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
7479 -- and not use Set_TSS in this case.
7481 -- There are also consequences for the case of delayed representation
7482 -- aspects for some cases. For example, a Size aspect is delayed and
7483 -- should not be evaluated to the freeze point. This early freezing
7484 -- means that the size attribute evaluation happens too early???
7486 if Is_Fixed_Point_Type (Parent_Type) then
7487 Conditional_Delay (Implicit_Base, Parent_Type);
7489 Freeze_Before (N, Implicit_Base);
7491 end Build_Derived_Numeric_Type;
7493 --------------------------------
7494 -- Build_Derived_Private_Type --
7495 --------------------------------
7497 procedure Build_Derived_Private_Type
7499 Parent_Type : Entity_Id;
7500 Derived_Type : Entity_Id;
7501 Is_Completion : Boolean;
7502 Derive_Subps : Boolean := True)
7504 Loc : constant Source_Ptr := Sloc (N);
7505 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
7506 Par_Scope : constant Entity_Id := Scope (Par_Base);
7507 Full_N : constant Node_Id := New_Copy_Tree (N);
7508 Full_Der : Entity_Id := New_Copy (Derived_Type);
7511 procedure Build_Full_Derivation;
7512 -- Build full derivation, i.e. derive from the full view
7514 procedure Copy_And_Build;
7515 -- Copy derived type declaration, replace parent with its full view,
7516 -- and build derivation
7518 ---------------------------
7519 -- Build_Full_Derivation --
7520 ---------------------------
7522 procedure Build_Full_Derivation is
7524 -- If parent scope is not open, install the declarations
7526 if not In_Open_Scopes (Par_Scope) then
7527 Install_Private_Declarations (Par_Scope);
7528 Install_Visible_Declarations (Par_Scope);
7530 Uninstall_Declarations (Par_Scope);
7532 -- If parent scope is open and in another unit, and parent has a
7533 -- completion, then the derivation is taking place in the visible
7534 -- part of a child unit. In that case retrieve the full view of
7535 -- the parent momentarily.
7537 elsif not In_Same_Source_Unit (N, Parent_Type) then
7538 Full_P := Full_View (Parent_Type);
7539 Exchange_Declarations (Parent_Type);
7541 Exchange_Declarations (Full_P);
7543 -- Otherwise it is a local derivation
7548 end Build_Full_Derivation;
7550 --------------------
7551 -- Copy_And_Build --
7552 --------------------
7554 procedure Copy_And_Build is
7555 Full_Parent : Entity_Id := Parent_Type;
7558 -- If the parent is itself derived from another private type,
7559 -- installing the private declarations has not affected its
7560 -- privacy status, so use its own full view explicitly.
7562 if Is_Private_Type (Full_Parent)
7563 and then Present (Full_View (Full_Parent))
7565 Full_Parent := Full_View (Full_Parent);
7568 -- And its underlying full view if necessary
7570 if Is_Private_Type (Full_Parent)
7571 and then Present (Underlying_Full_View (Full_Parent))
7573 Full_Parent := Underlying_Full_View (Full_Parent);
7576 -- For record, access and most enumeration types, derivation from
7577 -- the full view requires a fully-fledged declaration. In the other
7578 -- cases, just use an itype.
7580 if Ekind (Full_Parent) in Record_Kind
7581 or else Ekind (Full_Parent) in Access_Kind
7583 (Ekind (Full_Parent) in Enumeration_Kind
7584 and then not Is_Standard_Character_Type (Full_Parent)
7585 and then not Is_Generic_Type (Root_Type (Full_Parent)))
7587 -- Copy and adjust declaration to provide a completion for what
7588 -- is originally a private declaration. Indicate that full view
7589 -- is internally generated.
7591 Set_Comes_From_Source (Full_N, False);
7592 Set_Comes_From_Source (Full_Der, False);
7593 Set_Parent (Full_Der, Full_N);
7594 Set_Defining_Identifier (Full_N, Full_Der);
7596 -- If there are no constraints, adjust the subtype mark
7598 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
7599 N_Subtype_Indication
7601 Set_Subtype_Indication
7602 (Type_Definition (Full_N),
7603 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
7606 Insert_After (N, Full_N);
7608 -- Build full view of derived type from full view of parent which
7609 -- is now installed. Subprograms have been derived on the partial
7610 -- view, the completion does not derive them anew.
7612 if Ekind (Full_Parent) in Record_Kind then
7614 -- If parent type is tagged, the completion inherits the proper
7615 -- primitive operations.
7617 if Is_Tagged_Type (Parent_Type) then
7618 Build_Derived_Record_Type
7619 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7621 Build_Derived_Record_Type
7622 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7627 (Full_N, Full_Parent, Full_Der,
7628 Is_Completion => False, Derive_Subps => False);
7631 -- The full declaration has been introduced into the tree and
7632 -- processed in the step above. It should not be analyzed again
7633 -- (when encountered later in the current list of declarations)
7634 -- to prevent spurious name conflicts. The full entity remains
7637 Set_Analyzed (Full_N);
7641 Make_Defining_Identifier (Sloc (Derived_Type),
7642 Chars => Chars (Derived_Type));
7643 Set_Is_Itype (Full_Der);
7644 Set_Associated_Node_For_Itype (Full_Der, N);
7645 Set_Parent (Full_Der, N);
7647 (N, Full_Parent, Full_Der,
7648 Is_Completion => False, Derive_Subps => False);
7651 Set_Has_Private_Declaration (Full_Der);
7652 Set_Has_Private_Declaration (Derived_Type);
7654 Set_Scope (Full_Der, Scope (Derived_Type));
7655 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7656 Set_Has_Size_Clause (Full_Der, False);
7657 Set_Has_Alignment_Clause (Full_Der, False);
7658 Set_Has_Delayed_Freeze (Full_Der);
7659 Set_Is_Frozen (Full_Der, False);
7660 Set_Freeze_Node (Full_Der, Empty);
7661 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7662 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7664 -- The convention on the base type may be set in the private part
7665 -- and not propagated to the subtype until later, so we obtain the
7666 -- convention from the base type of the parent.
7668 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7671 -- Start of processing for Build_Derived_Private_Type
7674 if Is_Tagged_Type (Parent_Type) then
7675 Full_P := Full_View (Parent_Type);
7677 -- A type extension of a type with unknown discriminants is an
7678 -- indefinite type that the back-end cannot handle directly.
7679 -- We treat it as a private type, and build a completion that is
7680 -- derived from the full view of the parent, and hopefully has
7681 -- known discriminants.
7683 -- If the full view of the parent type has an underlying record view,
7684 -- use it to generate the underlying record view of this derived type
7685 -- (required for chains of derivations with unknown discriminants).
7687 -- Minor optimization: we avoid the generation of useless underlying
7688 -- record view entities if the private type declaration has unknown
7689 -- discriminants but its corresponding full view has no
7692 if Has_Unknown_Discriminants (Parent_Type)
7693 and then Present (Full_P)
7694 and then (Has_Discriminants (Full_P)
7695 or else Present (Underlying_Record_View (Full_P)))
7696 and then not In_Open_Scopes (Par_Scope)
7697 and then Expander_Active
7700 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7701 New_Ext : constant Node_Id :=
7703 (Record_Extension_Part (Type_Definition (N)));
7707 Build_Derived_Record_Type
7708 (N, Parent_Type, Derived_Type, Derive_Subps);
7710 -- Build anonymous completion, as a derivation from the full
7711 -- view of the parent. This is not a completion in the usual
7712 -- sense, because the current type is not private.
7715 Make_Full_Type_Declaration (Loc,
7716 Defining_Identifier => Full_Der,
7718 Make_Derived_Type_Definition (Loc,
7719 Subtype_Indication =>
7721 (Subtype_Indication (Type_Definition (N))),
7722 Record_Extension_Part => New_Ext));
7724 -- If the parent type has an underlying record view, use it
7725 -- here to build the new underlying record view.
7727 if Present (Underlying_Record_View (Full_P)) then
7729 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7731 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7732 Underlying_Record_View (Full_P));
7735 Install_Private_Declarations (Par_Scope);
7736 Install_Visible_Declarations (Par_Scope);
7737 Insert_Before (N, Decl);
7739 -- Mark entity as an underlying record view before analysis,
7740 -- to avoid generating the list of its primitive operations
7741 -- (which is not really required for this entity) and thus
7742 -- prevent spurious errors associated with missing overriding
7743 -- of abstract primitives (overridden only for Derived_Type).
7745 Set_Ekind (Full_Der, E_Record_Type);
7746 Set_Is_Underlying_Record_View (Full_Der);
7747 Set_Default_SSO (Full_Der);
7748 Set_No_Reordering (Full_Der, No_Component_Reordering);
7752 pragma Assert (Has_Discriminants (Full_Der)
7753 and then not Has_Unknown_Discriminants (Full_Der));
7755 Uninstall_Declarations (Par_Scope);
7757 -- Freeze the underlying record view, to prevent generation of
7758 -- useless dispatching information, which is simply shared with
7759 -- the real derived type.
7761 Set_Is_Frozen (Full_Der);
7763 -- If the derived type has access discriminants, create
7764 -- references to their anonymous types now, to prevent
7765 -- back-end problems when their first use is in generated
7766 -- bodies of primitives.
7772 E := First_Entity (Full_Der);
7774 while Present (E) loop
7775 if Ekind (E) = E_Discriminant
7776 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7778 Build_Itype_Reference (Etype (E), Decl);
7785 -- Set up links between real entity and underlying record view
7787 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7788 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7791 -- If discriminants are known, build derived record
7794 Build_Derived_Record_Type
7795 (N, Parent_Type, Derived_Type, Derive_Subps);
7800 elsif Has_Discriminants (Parent_Type) then
7802 -- Build partial view of derived type from partial view of parent.
7803 -- This must be done before building the full derivation because the
7804 -- second derivation will modify the discriminants of the first and
7805 -- the discriminants are chained with the rest of the components in
7806 -- the full derivation.
7808 Build_Derived_Record_Type
7809 (N, Parent_Type, Derived_Type, Derive_Subps);
7811 -- Build the full derivation if this is not the anonymous derived
7812 -- base type created by Build_Derived_Record_Type in the constrained
7813 -- case (see point 5. of its head comment) since we build it for the
7814 -- derived subtype. And skip it for protected types altogether, as
7815 -- gigi does not use these types directly.
7817 if Present (Full_View (Parent_Type))
7818 and then not Is_Itype (Derived_Type)
7819 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7822 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7824 Last_Discr : Entity_Id;
7827 -- If this is not a completion, construct the implicit full
7828 -- view by deriving from the full view of the parent type.
7829 -- But if this is a completion, the derived private type
7830 -- being built is a full view and the full derivation can
7831 -- only be its underlying full view.
7833 Build_Full_Derivation;
7835 if not Is_Completion then
7836 Set_Full_View (Derived_Type, Full_Der);
7838 Set_Underlying_Full_View (Derived_Type, Full_Der);
7839 Set_Is_Underlying_Full_View (Full_Der);
7842 if not Is_Base_Type (Derived_Type) then
7843 Set_Full_View (Der_Base, Base_Type (Full_Der));
7846 -- Copy the discriminant list from full view to the partial
7847 -- view (base type and its subtype). Gigi requires that the
7848 -- partial and full views have the same discriminants.
7850 -- Note that since the partial view points to discriminants
7851 -- in the full view, their scope will be that of the full
7852 -- view. This might cause some front end problems and need
7855 Discr := First_Discriminant (Base_Type (Full_Der));
7856 Set_First_Entity (Der_Base, Discr);
7859 Last_Discr := Discr;
7860 Next_Discriminant (Discr);
7861 exit when No (Discr);
7864 Set_Last_Entity (Der_Base, Last_Discr);
7865 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7866 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7870 elsif Present (Full_View (Parent_Type))
7871 and then Has_Discriminants (Full_View (Parent_Type))
7873 if Has_Unknown_Discriminants (Parent_Type)
7874 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7875 N_Subtype_Indication
7878 ("cannot constrain type with unknown discriminants",
7879 Subtype_Indication (Type_Definition (N)));
7883 -- If this is not a completion, construct the implicit full view by
7884 -- deriving from the full view of the parent type. But if this is a
7885 -- completion, the derived private type being built is a full view
7886 -- and the full derivation can only be its underlying full view.
7888 Build_Full_Derivation;
7890 if not Is_Completion then
7891 Set_Full_View (Derived_Type, Full_Der);
7893 Set_Underlying_Full_View (Derived_Type, Full_Der);
7894 Set_Is_Underlying_Full_View (Full_Der);
7897 -- In any case, the primitive operations are inherited from the
7898 -- parent type, not from the internal full view.
7900 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7902 if Derive_Subps then
7903 Derive_Subprograms (Parent_Type, Derived_Type);
7906 Set_Stored_Constraint (Derived_Type, No_Elist);
7908 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7911 -- Untagged type, No discriminants on either view
7913 if Nkind (Subtype_Indication (Type_Definition (N))) =
7914 N_Subtype_Indication
7917 ("illegal constraint on type without discriminants", N);
7920 if Present (Discriminant_Specifications (N))
7921 and then Present (Full_View (Parent_Type))
7922 and then not Is_Tagged_Type (Full_View (Parent_Type))
7924 Error_Msg_N ("cannot add discriminants to untagged type", N);
7927 Set_Stored_Constraint (Derived_Type, No_Elist);
7928 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7930 Set_Is_Controlled_Active
7931 (Derived_Type, Is_Controlled_Active (Parent_Type));
7933 Set_Disable_Controlled
7934 (Derived_Type, Disable_Controlled (Parent_Type));
7936 Set_Has_Controlled_Component
7937 (Derived_Type, Has_Controlled_Component (Parent_Type));
7939 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7941 if not Is_Controlled (Parent_Type) then
7942 Set_Finalize_Storage_Only
7943 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7946 -- If this is not a completion, construct the implicit full view by
7947 -- deriving from the full view of the parent type.
7949 -- ??? If the parent is untagged private and its completion is
7950 -- tagged, this mechanism will not work because we cannot derive from
7951 -- the tagged full view unless we have an extension.
7953 if Present (Full_View (Parent_Type))
7954 and then not Is_Tagged_Type (Full_View (Parent_Type))
7955 and then not Is_Completion
7957 Build_Full_Derivation;
7958 Set_Full_View (Derived_Type, Full_Der);
7962 Set_Has_Unknown_Discriminants (Derived_Type,
7963 Has_Unknown_Discriminants (Parent_Type));
7965 if Is_Private_Type (Derived_Type) then
7966 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7969 -- If the parent base type is in scope, add the derived type to its
7970 -- list of private dependents, because its full view may become
7971 -- visible subsequently (in a nested private part, a body, or in a
7972 -- further child unit).
7974 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7975 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7977 -- Check for unusual case where a type completed by a private
7978 -- derivation occurs within a package nested in a child unit, and
7979 -- the parent is declared in an ancestor.
7981 if Is_Child_Unit (Scope (Current_Scope))
7982 and then Is_Completion
7983 and then In_Private_Part (Current_Scope)
7984 and then Scope (Parent_Type) /= Current_Scope
7986 -- Note that if the parent has a completion in the private part,
7987 -- (which is itself a derivation from some other private type)
7988 -- it is that completion that is visible, there is no full view
7989 -- available, and no special processing is needed.
7991 and then Present (Full_View (Parent_Type))
7993 -- In this case, the full view of the parent type will become
7994 -- visible in the body of the enclosing child, and only then will
7995 -- the current type be possibly non-private. Build an underlying
7996 -- full view that will be installed when the enclosing child body
7999 if Present (Underlying_Full_View (Derived_Type)) then
8000 Full_Der := Underlying_Full_View (Derived_Type);
8002 Build_Full_Derivation;
8003 Set_Underlying_Full_View (Derived_Type, Full_Der);
8004 Set_Is_Underlying_Full_View (Full_Der);
8007 -- The full view will be used to swap entities on entry/exit to
8008 -- the body, and must appear in the entity list for the package.
8010 Append_Entity (Full_Der, Scope (Derived_Type));
8013 end Build_Derived_Private_Type;
8015 -------------------------------
8016 -- Build_Derived_Record_Type --
8017 -------------------------------
8021 -- Ideally we would like to use the same model of type derivation for
8022 -- tagged and untagged record types. Unfortunately this is not quite
8023 -- possible because the semantics of representation clauses is different
8024 -- for tagged and untagged records under inheritance. Consider the
8027 -- type R (...) is [tagged] record ... end record;
8028 -- type T (...) is new R (...) [with ...];
8030 -- The representation clauses for T can specify a completely different
8031 -- record layout from R's. Hence the same component can be placed in two
8032 -- very different positions in objects of type T and R. If R and T are
8033 -- tagged types, representation clauses for T can only specify the layout
8034 -- of non inherited components, thus components that are common in R and T
8035 -- have the same position in objects of type R and T.
8037 -- This has two implications. The first is that the entire tree for R's
8038 -- declaration needs to be copied for T in the untagged case, so that T
8039 -- can be viewed as a record type of its own with its own representation
8040 -- clauses. The second implication is the way we handle discriminants.
8041 -- Specifically, in the untagged case we need a way to communicate to Gigi
8042 -- what are the real discriminants in the record, while for the semantics
8043 -- we need to consider those introduced by the user to rename the
8044 -- discriminants in the parent type. This is handled by introducing the
8045 -- notion of stored discriminants. See below for more.
8047 -- Fortunately the way regular components are inherited can be handled in
8048 -- the same way in tagged and untagged types.
8050 -- To complicate things a bit more the private view of a private extension
8051 -- cannot be handled in the same way as the full view (for one thing the
8052 -- semantic rules are somewhat different). We will explain what differs
8055 -- 2. DISCRIMINANTS UNDER INHERITANCE
8057 -- The semantic rules governing the discriminants of derived types are
8060 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
8061 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
8063 -- If parent type has discriminants, then the discriminants that are
8064 -- declared in the derived type are [3.4 (11)]:
8066 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
8069 -- o Otherwise, each discriminant of the parent type (implicitly declared
8070 -- in the same order with the same specifications). In this case, the
8071 -- discriminants are said to be "inherited", or if unknown in the parent
8072 -- are also unknown in the derived type.
8074 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
8076 -- o The parent subtype must be constrained;
8078 -- o If the parent type is not a tagged type, then each discriminant of
8079 -- the derived type must be used in the constraint defining a parent
8080 -- subtype. [Implementation note: This ensures that the new discriminant
8081 -- can share storage with an existing discriminant.]
8083 -- For the derived type each discriminant of the parent type is either
8084 -- inherited, constrained to equal some new discriminant of the derived
8085 -- type, or constrained to the value of an expression.
8087 -- When inherited or constrained to equal some new discriminant, the
8088 -- parent discriminant and the discriminant of the derived type are said
8091 -- If a discriminant of the parent type is constrained to a specific value
8092 -- in the derived type definition, then the discriminant is said to be
8093 -- "specified" by that derived type definition.
8095 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
8097 -- We have spoken about stored discriminants in point 1 (introduction)
8098 -- above. There are two sorts of stored discriminants: implicit and
8099 -- explicit. As long as the derived type inherits the same discriminants as
8100 -- the root record type, stored discriminants are the same as regular
8101 -- discriminants, and are said to be implicit. However, if any discriminant
8102 -- in the root type was renamed in the derived type, then the derived
8103 -- type will contain explicit stored discriminants. Explicit stored
8104 -- discriminants are discriminants in addition to the semantically visible
8105 -- discriminants defined for the derived type. Stored discriminants are
8106 -- used by Gigi to figure out what are the physical discriminants in
8107 -- objects of the derived type (see precise definition in einfo.ads).
8108 -- As an example, consider the following:
8110 -- type R (D1, D2, D3 : Int) is record ... end record;
8111 -- type T1 is new R;
8112 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
8113 -- type T3 is new T2;
8114 -- type T4 (Y : Int) is new T3 (Y, 99);
8116 -- The following table summarizes the discriminants and stored
8117 -- discriminants in R and T1 through T4:
8119 -- Type Discrim Stored Discrim Comment
8120 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
8121 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
8122 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
8123 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
8124 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
8126 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
8127 -- find the corresponding discriminant in the parent type, while
8128 -- Original_Record_Component (abbreviated ORC below) the actual physical
8129 -- component that is renamed. Finally the field Is_Completely_Hidden
8130 -- (abbreviated ICH below) is set for all explicit stored discriminants
8131 -- (see einfo.ads for more info). For the above example this gives:
8133 -- Discrim CD ORC ICH
8134 -- ^^^^^^^ ^^ ^^^ ^^^
8135 -- D1 in R empty itself no
8136 -- D2 in R empty itself no
8137 -- D3 in R empty itself no
8139 -- D1 in T1 D1 in R itself no
8140 -- D2 in T1 D2 in R itself no
8141 -- D3 in T1 D3 in R itself no
8143 -- X1 in T2 D3 in T1 D3 in T2 no
8144 -- X2 in T2 D1 in T1 D1 in T2 no
8145 -- D1 in T2 empty itself yes
8146 -- D2 in T2 empty itself yes
8147 -- D3 in T2 empty itself yes
8149 -- X1 in T3 X1 in T2 D3 in T3 no
8150 -- X2 in T3 X2 in T2 D1 in T3 no
8151 -- D1 in T3 empty itself yes
8152 -- D2 in T3 empty itself yes
8153 -- D3 in T3 empty itself yes
8155 -- Y in T4 X1 in T3 D3 in T4 no
8156 -- D1 in T4 empty itself yes
8157 -- D2 in T4 empty itself yes
8158 -- D3 in T4 empty itself yes
8160 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
8162 -- Type derivation for tagged types is fairly straightforward. If no
8163 -- discriminants are specified by the derived type, these are inherited
8164 -- from the parent. No explicit stored discriminants are ever necessary.
8165 -- The only manipulation that is done to the tree is that of adding a
8166 -- _parent field with parent type and constrained to the same constraint
8167 -- specified for the parent in the derived type definition. For instance:
8169 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
8170 -- type T1 is new R with null record;
8171 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
8173 -- are changed into:
8175 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
8176 -- _parent : R (D1, D2, D3);
8179 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
8180 -- _parent : T1 (X2, 88, X1);
8183 -- The discriminants actually present in R, T1 and T2 as well as their CD,
8184 -- ORC and ICH fields are:
8186 -- Discrim CD ORC ICH
8187 -- ^^^^^^^ ^^ ^^^ ^^^
8188 -- D1 in R empty itself no
8189 -- D2 in R empty itself no
8190 -- D3 in R empty itself no
8192 -- D1 in T1 D1 in R D1 in R no
8193 -- D2 in T1 D2 in R D2 in R no
8194 -- D3 in T1 D3 in R D3 in R no
8196 -- X1 in T2 D3 in T1 D3 in R no
8197 -- X2 in T2 D1 in T1 D1 in R no
8199 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
8201 -- Regardless of whether we dealing with a tagged or untagged type
8202 -- we will transform all derived type declarations of the form
8204 -- type T is new R (...) [with ...];
8206 -- subtype S is R (...);
8207 -- type T is new S [with ...];
8209 -- type BT is new R [with ...];
8210 -- subtype T is BT (...);
8212 -- That is, the base derived type is constrained only if it has no
8213 -- discriminants. The reason for doing this is that GNAT's semantic model
8214 -- assumes that a base type with discriminants is unconstrained.
8216 -- Note that, strictly speaking, the above transformation is not always
8217 -- correct. Consider for instance the following excerpt from ACVC b34011a:
8219 -- procedure B34011A is
8220 -- type REC (D : integer := 0) is record
8225 -- type T6 is new Rec;
8226 -- function F return T6;
8231 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
8234 -- The definition of Q6.U is illegal. However transforming Q6.U into
8236 -- type BaseU is new T6;
8237 -- subtype U is BaseU (Q6.F.I)
8239 -- turns U into a legal subtype, which is incorrect. To avoid this problem
8240 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
8241 -- the transformation described above.
8243 -- There is another instance where the above transformation is incorrect.
8247 -- type Base (D : Integer) is tagged null record;
8248 -- procedure P (X : Base);
8250 -- type Der is new Base (2) with null record;
8251 -- procedure P (X : Der);
8254 -- Then the above transformation turns this into
8256 -- type Der_Base is new Base with null record;
8257 -- -- procedure P (X : Base) is implicitly inherited here
8258 -- -- as procedure P (X : Der_Base).
8260 -- subtype Der is Der_Base (2);
8261 -- procedure P (X : Der);
8262 -- -- The overriding of P (X : Der_Base) is illegal since we
8263 -- -- have a parameter conformance problem.
8265 -- To get around this problem, after having semantically processed Der_Base
8266 -- and the rewritten subtype declaration for Der, we copy Der_Base field
8267 -- Discriminant_Constraint from Der so that when parameter conformance is
8268 -- checked when P is overridden, no semantic errors are flagged.
8270 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
8272 -- Regardless of whether we are dealing with a tagged or untagged type
8273 -- we will transform all derived type declarations of the form
8275 -- type R (D1, .., Dn : ...) is [tagged] record ...;
8276 -- type T is new R [with ...];
8278 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
8280 -- The reason for such transformation is that it allows us to implement a
8281 -- very clean form of component inheritance as explained below.
8283 -- Note that this transformation is not achieved by direct tree rewriting
8284 -- and manipulation, but rather by redoing the semantic actions that the
8285 -- above transformation will entail. This is done directly in routine
8286 -- Inherit_Components.
8288 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
8290 -- In both tagged and untagged derived types, regular non discriminant
8291 -- components are inherited in the derived type from the parent type. In
8292 -- the absence of discriminants component, inheritance is straightforward
8293 -- as components can simply be copied from the parent.
8295 -- If the parent has discriminants, inheriting components constrained with
8296 -- these discriminants requires caution. Consider the following example:
8298 -- type R (D1, D2 : Positive) is [tagged] record
8299 -- S : String (D1 .. D2);
8302 -- type T1 is new R [with null record];
8303 -- type T2 (X : positive) is new R (1, X) [with null record];
8305 -- As explained in 6. above, T1 is rewritten as
8306 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
8307 -- which makes the treatment for T1 and T2 identical.
8309 -- What we want when inheriting S, is that references to D1 and D2 in R are
8310 -- replaced with references to their correct constraints, i.e. D1 and D2 in
8311 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
8312 -- with either discriminant references in the derived type or expressions.
8313 -- This replacement is achieved as follows: before inheriting R's
8314 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
8315 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
8316 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
8317 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
8318 -- by String (1 .. X).
8320 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
8322 -- We explain here the rules governing private type extensions relevant to
8323 -- type derivation. These rules are explained on the following example:
8325 -- type D [(...)] is new A [(...)] with private; <-- partial view
8326 -- type D [(...)] is new P [(...)] with null record; <-- full view
8328 -- Type A is called the ancestor subtype of the private extension.
8329 -- Type P is the parent type of the full view of the private extension. It
8330 -- must be A or a type derived from A.
8332 -- The rules concerning the discriminants of private type extensions are
8335 -- o If a private extension inherits known discriminants from the ancestor
8336 -- subtype, then the full view must also inherit its discriminants from
8337 -- the ancestor subtype and the parent subtype of the full view must be
8338 -- constrained if and only if the ancestor subtype is constrained.
8340 -- o If a partial view has unknown discriminants, then the full view may
8341 -- define a definite or an indefinite subtype, with or without
8344 -- o If a partial view has neither known nor unknown discriminants, then
8345 -- the full view must define a definite subtype.
8347 -- o If the ancestor subtype of a private extension has constrained
8348 -- discriminants, then the parent subtype of the full view must impose a
8349 -- statically matching constraint on those discriminants.
8351 -- This means that only the following forms of private extensions are
8354 -- type D is new A with private; <-- partial view
8355 -- type D is new P with null record; <-- full view
8357 -- If A has no discriminants than P has no discriminants, otherwise P must
8358 -- inherit A's discriminants.
8360 -- type D is new A (...) with private; <-- partial view
8361 -- type D is new P (:::) with null record; <-- full view
8363 -- P must inherit A's discriminants and (...) and (:::) must statically
8366 -- subtype A is R (...);
8367 -- type D is new A with private; <-- partial view
8368 -- type D is new P with null record; <-- full view
8370 -- P must have inherited R's discriminants and must be derived from A or
8371 -- any of its subtypes.
8373 -- type D (..) is new A with private; <-- partial view
8374 -- type D (..) is new P [(:::)] with null record; <-- full view
8376 -- No specific constraints on P's discriminants or constraint (:::).
8377 -- Note that A can be unconstrained, but the parent subtype P must either
8378 -- be constrained or (:::) must be present.
8380 -- type D (..) is new A [(...)] with private; <-- partial view
8381 -- type D (..) is new P [(:::)] with null record; <-- full view
8383 -- P's constraints on A's discriminants must statically match those
8384 -- imposed by (...).
8386 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
8388 -- The full view of a private extension is handled exactly as described
8389 -- above. The model chose for the private view of a private extension is
8390 -- the same for what concerns discriminants (i.e. they receive the same
8391 -- treatment as in the tagged case). However, the private view of the
8392 -- private extension always inherits the components of the parent base,
8393 -- without replacing any discriminant reference. Strictly speaking this is
8394 -- incorrect. However, Gigi never uses this view to generate code so this
8395 -- is a purely semantic issue. In theory, a set of transformations similar
8396 -- to those given in 5. and 6. above could be applied to private views of
8397 -- private extensions to have the same model of component inheritance as
8398 -- for non private extensions. However, this is not done because it would
8399 -- further complicate private type processing. Semantically speaking, this
8400 -- leaves us in an uncomfortable situation. As an example consider:
8403 -- type R (D : integer) is tagged record
8404 -- S : String (1 .. D);
8406 -- procedure P (X : R);
8407 -- type T is new R (1) with private;
8409 -- type T is new R (1) with null record;
8412 -- This is transformed into:
8415 -- type R (D : integer) is tagged record
8416 -- S : String (1 .. D);
8418 -- procedure P (X : R);
8419 -- type T is new R (1) with private;
8421 -- type BaseT is new R with null record;
8422 -- subtype T is BaseT (1);
8425 -- (strictly speaking the above is incorrect Ada)
8427 -- From the semantic standpoint the private view of private extension T
8428 -- should be flagged as constrained since one can clearly have
8432 -- in a unit withing Pack. However, when deriving subprograms for the
8433 -- private view of private extension T, T must be seen as unconstrained
8434 -- since T has discriminants (this is a constraint of the current
8435 -- subprogram derivation model). Thus, when processing the private view of
8436 -- a private extension such as T, we first mark T as unconstrained, we
8437 -- process it, we perform program derivation and just before returning from
8438 -- Build_Derived_Record_Type we mark T as constrained.
8440 -- ??? Are there are other uncomfortable cases that we will have to
8443 -- 10. RECORD_TYPE_WITH_PRIVATE complications
8445 -- Types that are derived from a visible record type and have a private
8446 -- extension present other peculiarities. They behave mostly like private
8447 -- types, but if they have primitive operations defined, these will not
8448 -- have the proper signatures for further inheritance, because other
8449 -- primitive operations will use the implicit base that we define for
8450 -- private derivations below. This affect subprogram inheritance (see
8451 -- Derive_Subprograms for details). We also derive the implicit base from
8452 -- the base type of the full view, so that the implicit base is a record
8453 -- type and not another private type, This avoids infinite loops.
8455 procedure Build_Derived_Record_Type
8457 Parent_Type : Entity_Id;
8458 Derived_Type : Entity_Id;
8459 Derive_Subps : Boolean := True)
8461 Discriminant_Specs : constant Boolean :=
8462 Present (Discriminant_Specifications (N));
8463 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
8464 Loc : constant Source_Ptr := Sloc (N);
8465 Private_Extension : constant Boolean :=
8466 Nkind (N) = N_Private_Extension_Declaration;
8467 Assoc_List : Elist_Id;
8468 Constraint_Present : Boolean;
8470 Discrim : Entity_Id;
8472 Inherit_Discrims : Boolean := False;
8473 Last_Discrim : Entity_Id;
8474 New_Base : Entity_Id;
8476 New_Discrs : Elist_Id;
8477 New_Indic : Node_Id;
8478 Parent_Base : Entity_Id;
8479 Save_Etype : Entity_Id;
8480 Save_Discr_Constr : Elist_Id;
8481 Save_Next_Entity : Entity_Id;
8484 Discs : Elist_Id := New_Elmt_List;
8485 -- An empty Discs list means that there were no constraints in the
8486 -- subtype indication or that there was an error processing it.
8489 if Ekind (Parent_Type) = E_Record_Type_With_Private
8490 and then Present (Full_View (Parent_Type))
8491 and then Has_Discriminants (Parent_Type)
8493 Parent_Base := Base_Type (Full_View (Parent_Type));
8495 Parent_Base := Base_Type (Parent_Type);
8498 -- AI05-0115 : if this is a derivation from a private type in some
8499 -- other scope that may lead to invisible components for the derived
8500 -- type, mark it accordingly.
8502 if Is_Private_Type (Parent_Type) then
8503 if Scope (Parent_Type) = Scope (Derived_Type) then
8506 elsif In_Open_Scopes (Scope (Parent_Type))
8507 and then In_Private_Part (Scope (Parent_Type))
8512 Set_Has_Private_Ancestor (Derived_Type);
8516 Set_Has_Private_Ancestor
8517 (Derived_Type, Has_Private_Ancestor (Parent_Type));
8520 -- Before we start the previously documented transformations, here is
8521 -- little fix for size and alignment of tagged types. Normally when we
8522 -- derive type D from type P, we copy the size and alignment of P as the
8523 -- default for D, and in the absence of explicit representation clauses
8524 -- for D, the size and alignment are indeed the same as the parent.
8526 -- But this is wrong for tagged types, since fields may be added, and
8527 -- the default size may need to be larger, and the default alignment may
8528 -- need to be larger.
8530 -- We therefore reset the size and alignment fields in the tagged case.
8531 -- Note that the size and alignment will in any case be at least as
8532 -- large as the parent type (since the derived type has a copy of the
8533 -- parent type in the _parent field)
8535 -- The type is also marked as being tagged here, which is needed when
8536 -- processing components with a self-referential anonymous access type
8537 -- in the call to Check_Anonymous_Access_Components below. Note that
8538 -- this flag is also set later on for completeness.
8541 Set_Is_Tagged_Type (Derived_Type);
8542 Init_Size_Align (Derived_Type);
8545 -- STEP 0a: figure out what kind of derived type declaration we have
8547 if Private_Extension then
8549 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
8550 Set_Default_SSO (Derived_Type);
8551 Set_No_Reordering (Derived_Type, No_Component_Reordering);
8554 Type_Def := Type_Definition (N);
8556 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8557 -- Parent_Base can be a private type or private extension. However,
8558 -- for tagged types with an extension the newly added fields are
8559 -- visible and hence the Derived_Type is always an E_Record_Type.
8560 -- (except that the parent may have its own private fields).
8561 -- For untagged types we preserve the Ekind of the Parent_Base.
8563 if Present (Record_Extension_Part (Type_Def)) then
8564 Set_Ekind (Derived_Type, E_Record_Type);
8565 Set_Default_SSO (Derived_Type);
8566 Set_No_Reordering (Derived_Type, No_Component_Reordering);
8568 -- Create internal access types for components with anonymous
8571 if Ada_Version >= Ada_2005 then
8572 Check_Anonymous_Access_Components
8573 (N, Derived_Type, Derived_Type,
8574 Component_List (Record_Extension_Part (Type_Def)));
8578 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8582 -- Indic can either be an N_Identifier if the subtype indication
8583 -- contains no constraint or an N_Subtype_Indication if the subtype
8584 -- indication has a constraint.
8586 Indic := Subtype_Indication (Type_Def);
8587 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
8589 -- Check that the type has visible discriminants. The type may be
8590 -- a private type with unknown discriminants whose full view has
8591 -- discriminants which are invisible.
8593 if Constraint_Present then
8594 if not Has_Discriminants (Parent_Base)
8596 (Has_Unknown_Discriminants (Parent_Base)
8597 and then Is_Private_Type (Parent_Base))
8600 ("invalid constraint: type has no discriminant",
8601 Constraint (Indic));
8603 Constraint_Present := False;
8604 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8606 elsif Is_Constrained (Parent_Type) then
8608 ("invalid constraint: parent type is already constrained",
8609 Constraint (Indic));
8611 Constraint_Present := False;
8612 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8616 -- STEP 0b: If needed, apply transformation given in point 5. above
8618 if not Private_Extension
8619 and then Has_Discriminants (Parent_Type)
8620 and then not Discriminant_Specs
8621 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8623 -- First, we must analyze the constraint (see comment in point 5.)
8624 -- The constraint may come from the subtype indication of the full
8627 if Constraint_Present then
8628 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8630 -- If there is no explicit constraint, there might be one that is
8631 -- inherited from a constrained parent type. In that case verify that
8632 -- it conforms to the constraint in the partial view. In perverse
8633 -- cases the parent subtypes of the partial and full view can have
8634 -- different constraints.
8636 elsif Present (Stored_Constraint (Parent_Type)) then
8637 New_Discrs := Stored_Constraint (Parent_Type);
8640 New_Discrs := No_Elist;
8643 if Has_Discriminants (Derived_Type)
8644 and then Has_Private_Declaration (Derived_Type)
8645 and then Present (Discriminant_Constraint (Derived_Type))
8646 and then Present (New_Discrs)
8648 -- Verify that constraints of the full view statically match
8649 -- those given in the partial view.
8655 C1 := First_Elmt (New_Discrs);
8656 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8657 while Present (C1) and then Present (C2) loop
8658 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8660 (Is_OK_Static_Expression (Node (C1))
8661 and then Is_OK_Static_Expression (Node (C2))
8663 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8668 if Constraint_Present then
8670 ("constraint not conformant to previous declaration",
8674 ("constraint of full view is incompatible "
8675 & "with partial view", N);
8685 -- Insert and analyze the declaration for the unconstrained base type
8687 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8690 Make_Full_Type_Declaration (Loc,
8691 Defining_Identifier => New_Base,
8693 Make_Derived_Type_Definition (Loc,
8694 Abstract_Present => Abstract_Present (Type_Def),
8695 Limited_Present => Limited_Present (Type_Def),
8696 Subtype_Indication =>
8697 New_Occurrence_Of (Parent_Base, Loc),
8698 Record_Extension_Part =>
8699 Relocate_Node (Record_Extension_Part (Type_Def)),
8700 Interface_List => Interface_List (Type_Def)));
8702 Set_Parent (New_Decl, Parent (N));
8703 Mark_Rewrite_Insertion (New_Decl);
8704 Insert_Before (N, New_Decl);
8706 -- In the extension case, make sure ancestor is frozen appropriately
8707 -- (see also non-discriminated case below).
8709 if Present (Record_Extension_Part (Type_Def))
8710 or else Is_Interface (Parent_Base)
8712 Freeze_Before (New_Decl, Parent_Type);
8715 -- Note that this call passes False for the Derive_Subps parameter
8716 -- because subprogram derivation is deferred until after creating
8717 -- the subtype (see below).
8720 (New_Decl, Parent_Base, New_Base,
8721 Is_Completion => False, Derive_Subps => False);
8723 -- ??? This needs re-examination to determine whether the
8724 -- above call can simply be replaced by a call to Analyze.
8726 Set_Analyzed (New_Decl);
8728 -- Insert and analyze the declaration for the constrained subtype
8730 if Constraint_Present then
8732 Make_Subtype_Indication (Loc,
8733 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8734 Constraint => Relocate_Node (Constraint (Indic)));
8738 Constr_List : constant List_Id := New_List;
8743 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8744 while Present (C) loop
8747 -- It is safe here to call New_Copy_Tree since we called
8748 -- Force_Evaluation on each constraint previously
8749 -- in Build_Discriminant_Constraints.
8751 Append (New_Copy_Tree (Expr), To => Constr_List);
8757 Make_Subtype_Indication (Loc,
8758 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8760 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8765 Make_Subtype_Declaration (Loc,
8766 Defining_Identifier => Derived_Type,
8767 Subtype_Indication => New_Indic));
8771 -- Derivation of subprograms must be delayed until the full subtype
8772 -- has been established, to ensure proper overriding of subprograms
8773 -- inherited by full types. If the derivations occurred as part of
8774 -- the call to Build_Derived_Type above, then the check for type
8775 -- conformance would fail because earlier primitive subprograms
8776 -- could still refer to the full type prior the change to the new
8777 -- subtype and hence would not match the new base type created here.
8778 -- Subprograms are not derived, however, when Derive_Subps is False
8779 -- (since otherwise there could be redundant derivations).
8781 if Derive_Subps then
8782 Derive_Subprograms (Parent_Type, Derived_Type);
8785 -- For tagged types the Discriminant_Constraint of the new base itype
8786 -- is inherited from the first subtype so that no subtype conformance
8787 -- problem arise when the first subtype overrides primitive
8788 -- operations inherited by the implicit base type.
8791 Set_Discriminant_Constraint
8792 (New_Base, Discriminant_Constraint (Derived_Type));
8798 -- If we get here Derived_Type will have no discriminants or it will be
8799 -- a discriminated unconstrained base type.
8801 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8805 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8806 -- The declaration of a specific descendant of an interface type
8807 -- freezes the interface type (RM 13.14).
8809 if not Private_Extension or else Is_Interface (Parent_Base) then
8810 Freeze_Before (N, Parent_Type);
8813 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8814 -- cannot be declared at a deeper level than its parent type is
8815 -- removed. The check on derivation within a generic body is also
8816 -- relaxed, but there's a restriction that a derived tagged type
8817 -- cannot be declared in a generic body if it's derived directly
8818 -- or indirectly from a formal type of that generic.
8820 if Ada_Version >= Ada_2005 then
8821 if Present (Enclosing_Generic_Body (Derived_Type)) then
8823 Ancestor_Type : Entity_Id;
8826 -- Check to see if any ancestor of the derived type is a
8829 Ancestor_Type := Parent_Type;
8830 while not Is_Generic_Type (Ancestor_Type)
8831 and then Etype (Ancestor_Type) /= Ancestor_Type
8833 Ancestor_Type := Etype (Ancestor_Type);
8836 -- If the derived type does have a formal type as an
8837 -- ancestor, then it's an error if the derived type is
8838 -- declared within the body of the generic unit that
8839 -- declares the formal type in its generic formal part. It's
8840 -- sufficient to check whether the ancestor type is declared
8841 -- inside the same generic body as the derived type (such as
8842 -- within a nested generic spec), in which case the
8843 -- derivation is legal. If the formal type is declared
8844 -- outside of that generic body, then it's guaranteed that
8845 -- the derived type is declared within the generic body of
8846 -- the generic unit declaring the formal type.
8848 if Is_Generic_Type (Ancestor_Type)
8849 and then Enclosing_Generic_Body (Ancestor_Type) /=
8850 Enclosing_Generic_Body (Derived_Type)
8853 ("parent type of& must not be descendant of formal type"
8854 & " of an enclosing generic body",
8855 Indic, Derived_Type);
8860 elsif Type_Access_Level (Derived_Type) /=
8861 Type_Access_Level (Parent_Type)
8862 and then not Is_Generic_Type (Derived_Type)
8864 if Is_Controlled (Parent_Type) then
8866 ("controlled type must be declared at the library level",
8870 ("type extension at deeper accessibility level than parent",
8876 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8879 and then GB /= Enclosing_Generic_Body (Parent_Base)
8882 ("parent type of& must not be outside generic body"
8884 Indic, Derived_Type);
8890 -- Ada 2005 (AI-251)
8892 if Ada_Version >= Ada_2005 and then Is_Tagged then
8894 -- "The declaration of a specific descendant of an interface type
8895 -- freezes the interface type" (RM 13.14).
8900 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8901 Iface := First (Interface_List (Type_Def));
8902 while Present (Iface) loop
8903 Freeze_Before (N, Etype (Iface));
8910 -- STEP 1b : preliminary cleanup of the full view of private types
8912 -- If the type is already marked as having discriminants, then it's the
8913 -- completion of a private type or private extension and we need to
8914 -- retain the discriminants from the partial view if the current
8915 -- declaration has Discriminant_Specifications so that we can verify
8916 -- conformance. However, we must remove any existing components that
8917 -- were inherited from the parent (and attached in Copy_And_Swap)
8918 -- because the full type inherits all appropriate components anyway, and
8919 -- we do not want the partial view's components interfering.
8921 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8922 Discrim := First_Discriminant (Derived_Type);
8924 Last_Discrim := Discrim;
8925 Next_Discriminant (Discrim);
8926 exit when No (Discrim);
8929 Set_Last_Entity (Derived_Type, Last_Discrim);
8931 -- In all other cases wipe out the list of inherited components (even
8932 -- inherited discriminants), it will be properly rebuilt here.
8935 Set_First_Entity (Derived_Type, Empty);
8936 Set_Last_Entity (Derived_Type, Empty);
8939 -- STEP 1c: Initialize some flags for the Derived_Type
8941 -- The following flags must be initialized here so that
8942 -- Process_Discriminants can check that discriminants of tagged types do
8943 -- not have a default initial value and that access discriminants are
8944 -- only specified for limited records. For completeness, these flags are
8945 -- also initialized along with all the other flags below.
8947 -- AI-419: Limitedness is not inherited from an interface parent, so to
8948 -- be limited in that case the type must be explicitly declared as
8949 -- limited. However, task and protected interfaces are always limited.
8951 if Limited_Present (Type_Def) then
8952 Set_Is_Limited_Record (Derived_Type);
8954 elsif Is_Limited_Record (Parent_Type)
8955 or else (Present (Full_View (Parent_Type))
8956 and then Is_Limited_Record (Full_View (Parent_Type)))
8958 if not Is_Interface (Parent_Type)
8959 or else Is_Synchronized_Interface (Parent_Type)
8960 or else Is_Protected_Interface (Parent_Type)
8961 or else Is_Task_Interface (Parent_Type)
8963 Set_Is_Limited_Record (Derived_Type);
8967 -- STEP 2a: process discriminants of derived type if any
8969 Push_Scope (Derived_Type);
8971 if Discriminant_Specs then
8972 Set_Has_Unknown_Discriminants (Derived_Type, False);
8974 -- The following call initializes fields Has_Discriminants and
8975 -- Discriminant_Constraint, unless we are processing the completion
8976 -- of a private type declaration.
8978 Check_Or_Process_Discriminants (N, Derived_Type);
8980 -- For untagged types, the constraint on the Parent_Type must be
8981 -- present and is used to rename the discriminants.
8983 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8984 Error_Msg_N ("untagged parent must have discriminants", Indic);
8986 elsif not Is_Tagged and then not Constraint_Present then
8988 ("discriminant constraint needed for derived untagged records",
8991 -- Otherwise the parent subtype must be constrained unless we have a
8992 -- private extension.
8994 elsif not Constraint_Present
8995 and then not Private_Extension
8996 and then not Is_Constrained (Parent_Type)
8999 ("unconstrained type not allowed in this context", Indic);
9001 elsif Constraint_Present then
9002 -- The following call sets the field Corresponding_Discriminant
9003 -- for the discriminants in the Derived_Type.
9005 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
9007 -- For untagged types all new discriminants must rename
9008 -- discriminants in the parent. For private extensions new
9009 -- discriminants cannot rename old ones (implied by [7.3(13)]).
9011 Discrim := First_Discriminant (Derived_Type);
9012 while Present (Discrim) loop
9014 and then No (Corresponding_Discriminant (Discrim))
9017 ("new discriminants must constrain old ones", Discrim);
9019 elsif Private_Extension
9020 and then Present (Corresponding_Discriminant (Discrim))
9023 ("only static constraints allowed for parent"
9024 & " discriminants in the partial view", Indic);
9028 -- If a new discriminant is used in the constraint, then its
9029 -- subtype must be statically compatible with the parent
9030 -- discriminant's subtype (3.7(15)).
9032 -- However, if the record contains an array constrained by
9033 -- the discriminant but with some different bound, the compiler
9034 -- tries to create a smaller range for the discriminant type.
9035 -- (See exp_ch3.Adjust_Discriminants). In this case, where
9036 -- the discriminant type is a scalar type, the check must use
9037 -- the original discriminant type in the parent declaration.
9040 Corr_Disc : constant Entity_Id :=
9041 Corresponding_Discriminant (Discrim);
9042 Disc_Type : constant Entity_Id := Etype (Discrim);
9043 Corr_Type : Entity_Id;
9046 if Present (Corr_Disc) then
9047 if Is_Scalar_Type (Disc_Type) then
9049 Entity (Discriminant_Type (Parent (Corr_Disc)));
9051 Corr_Type := Etype (Corr_Disc);
9055 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
9058 ("subtype must be compatible "
9059 & "with parent discriminant",
9065 Next_Discriminant (Discrim);
9068 -- Check whether the constraints of the full view statically
9069 -- match those imposed by the parent subtype [7.3(13)].
9071 if Present (Stored_Constraint (Derived_Type)) then
9076 C1 := First_Elmt (Discs);
9077 C2 := First_Elmt (Stored_Constraint (Derived_Type));
9078 while Present (C1) and then Present (C2) loop
9080 Fully_Conformant_Expressions (Node (C1), Node (C2))
9083 ("not conformant with previous declaration",
9094 -- STEP 2b: No new discriminants, inherit discriminants if any
9097 if Private_Extension then
9098 Set_Has_Unknown_Discriminants
9100 Has_Unknown_Discriminants (Parent_Type)
9101 or else Unknown_Discriminants_Present (N));
9103 -- The partial view of the parent may have unknown discriminants,
9104 -- but if the full view has discriminants and the parent type is
9105 -- in scope they must be inherited.
9107 elsif Has_Unknown_Discriminants (Parent_Type)
9109 (not Has_Discriminants (Parent_Type)
9110 or else not In_Open_Scopes (Scope (Parent_Type)))
9112 Set_Has_Unknown_Discriminants (Derived_Type);
9115 if not Has_Unknown_Discriminants (Derived_Type)
9116 and then not Has_Unknown_Discriminants (Parent_Base)
9117 and then Has_Discriminants (Parent_Type)
9119 Inherit_Discrims := True;
9120 Set_Has_Discriminants
9121 (Derived_Type, True);
9122 Set_Discriminant_Constraint
9123 (Derived_Type, Discriminant_Constraint (Parent_Base));
9126 -- The following test is true for private types (remember
9127 -- transformation 5. is not applied to those) and in an error
9130 if Constraint_Present then
9131 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
9134 -- For now mark a new derived type as constrained only if it has no
9135 -- discriminants. At the end of Build_Derived_Record_Type we properly
9136 -- set this flag in the case of private extensions. See comments in
9137 -- point 9. just before body of Build_Derived_Record_Type.
9141 not (Inherit_Discrims
9142 or else Has_Unknown_Discriminants (Derived_Type)));
9145 -- STEP 3: initialize fields of derived type
9147 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
9148 Set_Stored_Constraint (Derived_Type, No_Elist);
9150 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
9151 -- but cannot be interfaces
9153 if not Private_Extension
9154 and then Ekind (Derived_Type) /= E_Private_Type
9155 and then Ekind (Derived_Type) /= E_Limited_Private_Type
9157 if Interface_Present (Type_Def) then
9158 Analyze_Interface_Declaration (Derived_Type, Type_Def);
9161 Set_Interfaces (Derived_Type, No_Elist);
9164 -- Fields inherited from the Parent_Type
9166 Set_Has_Specified_Layout
9167 (Derived_Type, Has_Specified_Layout (Parent_Type));
9168 Set_Is_Limited_Composite
9169 (Derived_Type, Is_Limited_Composite (Parent_Type));
9170 Set_Is_Private_Composite
9171 (Derived_Type, Is_Private_Composite (Parent_Type));
9173 if Is_Tagged_Type (Parent_Type) then
9174 Set_No_Tagged_Streams_Pragma
9175 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9178 -- Fields inherited from the Parent_Base
9180 Set_Has_Controlled_Component
9181 (Derived_Type, Has_Controlled_Component (Parent_Base));
9182 Set_Has_Non_Standard_Rep
9183 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
9184 Set_Has_Primitive_Operations
9185 (Derived_Type, Has_Primitive_Operations (Parent_Base));
9187 -- Set fields for private derived types
9189 if Is_Private_Type (Derived_Type) then
9190 Set_Depends_On_Private (Derived_Type, True);
9191 Set_Private_Dependents (Derived_Type, New_Elmt_List);
9194 -- Inherit fields for non-private types. If this is the completion of a
9195 -- derivation from a private type, the parent itself is private and the
9196 -- attributes come from its full view, which must be present.
9198 if Is_Record_Type (Derived_Type) then
9200 Parent_Full : Entity_Id;
9203 if Is_Private_Type (Parent_Base)
9204 and then not Is_Record_Type (Parent_Base)
9206 Parent_Full := Full_View (Parent_Base);
9208 Parent_Full := Parent_Base;
9211 Set_Component_Alignment
9212 (Derived_Type, Component_Alignment (Parent_Full));
9214 (Derived_Type, C_Pass_By_Copy (Parent_Full));
9215 Set_Has_Complex_Representation
9216 (Derived_Type, Has_Complex_Representation (Parent_Full));
9218 -- For untagged types, inherit the layout by default to avoid
9219 -- costly changes of representation for type conversions.
9221 if not Is_Tagged then
9222 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Full));
9223 Set_No_Reordering (Derived_Type, No_Reordering (Parent_Full));
9228 -- Set fields for tagged types
9231 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
9233 -- All tagged types defined in Ada.Finalization are controlled
9235 if Chars (Scope (Derived_Type)) = Name_Finalization
9236 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
9237 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
9239 Set_Is_Controlled_Active (Derived_Type);
9241 Set_Is_Controlled_Active
9242 (Derived_Type, Is_Controlled_Active (Parent_Base));
9245 -- Minor optimization: there is no need to generate the class-wide
9246 -- entity associated with an underlying record view.
9248 if not Is_Underlying_Record_View (Derived_Type) then
9249 Make_Class_Wide_Type (Derived_Type);
9252 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
9254 if Has_Discriminants (Derived_Type)
9255 and then Constraint_Present
9257 Set_Stored_Constraint
9258 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
9261 if Ada_Version >= Ada_2005 then
9263 Ifaces_List : Elist_Id;
9266 -- Checks rules 3.9.4 (13/2 and 14/2)
9268 if Comes_From_Source (Derived_Type)
9269 and then not Is_Private_Type (Derived_Type)
9270 and then Is_Interface (Parent_Type)
9271 and then not Is_Interface (Derived_Type)
9273 if Is_Task_Interface (Parent_Type) then
9275 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
9278 elsif Is_Protected_Interface (Parent_Type) then
9280 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
9285 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
9287 Check_Interfaces (N, Type_Def);
9289 -- Ada 2005 (AI-251): Collect the list of progenitors that are
9290 -- not already in the parents.
9294 Ifaces_List => Ifaces_List,
9295 Exclude_Parents => True);
9297 Set_Interfaces (Derived_Type, Ifaces_List);
9299 -- If the derived type is the anonymous type created for
9300 -- a declaration whose parent has a constraint, propagate
9301 -- the interface list to the source type. This must be done
9302 -- prior to the completion of the analysis of the source type
9303 -- because the components in the extension may contain current
9304 -- instances whose legality depends on some ancestor.
9306 if Is_Itype (Derived_Type) then
9308 Def : constant Node_Id :=
9309 Associated_Node_For_Itype (Derived_Type);
9312 and then Nkind (Def) = N_Full_Type_Declaration
9315 (Defining_Identifier (Def), Ifaces_List);
9320 -- A type extension is automatically Ghost when one of its
9321 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
9322 -- also inherited when the parent type is Ghost, but this is
9323 -- done in Build_Derived_Type as the mechanism also handles
9324 -- untagged derivations.
9326 if Implements_Ghost_Interface (Derived_Type) then
9327 Set_Is_Ghost_Entity (Derived_Type);
9333 -- STEP 4: Inherit components from the parent base and constrain them.
9334 -- Apply the second transformation described in point 6. above.
9336 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
9337 or else not Has_Discriminants (Parent_Type)
9338 or else not Is_Constrained (Parent_Type)
9342 Constrs := Discriminant_Constraint (Parent_Type);
9347 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
9349 -- STEP 5a: Copy the parent record declaration for untagged types
9351 Set_Has_Implicit_Dereference
9352 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
9354 if not Is_Tagged then
9356 -- Discriminant_Constraint (Derived_Type) has been properly
9357 -- constructed. Save it and temporarily set it to Empty because we
9358 -- do not want the call to New_Copy_Tree below to mess this list.
9360 if Has_Discriminants (Derived_Type) then
9361 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
9362 Set_Discriminant_Constraint (Derived_Type, No_Elist);
9364 Save_Discr_Constr := No_Elist;
9367 -- Save the Etype field of Derived_Type. It is correctly set now,
9368 -- but the call to New_Copy tree may remap it to point to itself,
9369 -- which is not what we want. Ditto for the Next_Entity field.
9371 Save_Etype := Etype (Derived_Type);
9372 Save_Next_Entity := Next_Entity (Derived_Type);
9374 -- Assoc_List maps all stored discriminants in the Parent_Base to
9375 -- stored discriminants in the Derived_Type. It is fundamental that
9376 -- no types or itypes with discriminants other than the stored
9377 -- discriminants appear in the entities declared inside
9378 -- Derived_Type, since the back end cannot deal with it.
9382 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
9383 Copy_Dimensions_Of_Components (Derived_Type);
9385 -- Restore the fields saved prior to the New_Copy_Tree call
9386 -- and compute the stored constraint.
9388 Set_Etype (Derived_Type, Save_Etype);
9389 Set_Next_Entity (Derived_Type, Save_Next_Entity);
9391 if Has_Discriminants (Derived_Type) then
9392 Set_Discriminant_Constraint
9393 (Derived_Type, Save_Discr_Constr);
9394 Set_Stored_Constraint
9395 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
9396 Replace_Components (Derived_Type, New_Decl);
9399 -- Insert the new derived type declaration
9401 Rewrite (N, New_Decl);
9403 -- STEP 5b: Complete the processing for record extensions in generics
9405 -- There is no completion for record extensions declared in the
9406 -- parameter part of a generic, so we need to complete processing for
9407 -- these generic record extensions here. The Record_Type_Definition call
9408 -- will change the Ekind of the components from E_Void to E_Component.
9410 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
9411 Record_Type_Definition (Empty, Derived_Type);
9413 -- STEP 5c: Process the record extension for non private tagged types
9415 elsif not Private_Extension then
9416 Expand_Record_Extension (Derived_Type, Type_Def);
9418 -- Note : previously in ASIS mode we set the Parent_Subtype of the
9419 -- derived type to propagate some semantic information. This led
9420 -- to other ASIS failures and has been removed.
9422 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
9423 -- implemented interfaces if we are in expansion mode
9426 and then Has_Interfaces (Derived_Type)
9428 Add_Interface_Tag_Components (N, Derived_Type);
9431 -- Analyze the record extension
9433 Record_Type_Definition
9434 (Record_Extension_Part (Type_Def), Derived_Type);
9439 -- Nothing else to do if there is an error in the derivation.
9440 -- An unusual case: the full view may be derived from a type in an
9441 -- instance, when the partial view was used illegally as an actual
9442 -- in that instance, leading to a circular definition.
9444 if Etype (Derived_Type) = Any_Type
9445 or else Etype (Parent_Type) = Derived_Type
9450 -- Set delayed freeze and then derive subprograms, we need to do
9451 -- this in this order so that derived subprograms inherit the
9452 -- derived freeze if necessary.
9454 Set_Has_Delayed_Freeze (Derived_Type);
9456 if Derive_Subps then
9457 Derive_Subprograms (Parent_Type, Derived_Type);
9460 -- If we have a private extension which defines a constrained derived
9461 -- type mark as constrained here after we have derived subprograms. See
9462 -- comment on point 9. just above the body of Build_Derived_Record_Type.
9464 if Private_Extension and then Inherit_Discrims then
9465 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
9466 Set_Is_Constrained (Derived_Type, True);
9467 Set_Discriminant_Constraint (Derived_Type, Discs);
9469 elsif Is_Constrained (Parent_Type) then
9471 (Derived_Type, True);
9472 Set_Discriminant_Constraint
9473 (Derived_Type, Discriminant_Constraint (Parent_Type));
9477 -- Update the class-wide type, which shares the now-completed entity
9478 -- list with its specific type. In case of underlying record views,
9479 -- we do not generate the corresponding class wide entity.
9482 and then not Is_Underlying_Record_View (Derived_Type)
9485 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
9487 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
9490 Check_Function_Writable_Actuals (N);
9491 end Build_Derived_Record_Type;
9493 ------------------------
9494 -- Build_Derived_Type --
9495 ------------------------
9497 procedure Build_Derived_Type
9499 Parent_Type : Entity_Id;
9500 Derived_Type : Entity_Id;
9501 Is_Completion : Boolean;
9502 Derive_Subps : Boolean := True)
9504 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
9507 -- Set common attributes
9509 Set_Scope (Derived_Type, Current_Scope);
9510 Set_Etype (Derived_Type, Parent_Base);
9511 Set_Ekind (Derived_Type, Ekind (Parent_Base));
9512 Propagate_Concurrent_Flags (Derived_Type, Parent_Base);
9514 Set_Size_Info (Derived_Type, Parent_Type);
9515 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
9517 Set_Is_Controlled_Active
9518 (Derived_Type, Is_Controlled_Active (Parent_Type));
9520 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
9521 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
9522 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
9524 if Is_Tagged_Type (Derived_Type) then
9525 Set_No_Tagged_Streams_Pragma
9526 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9529 -- If the parent has primitive routines, set the derived type link
9531 if Has_Primitive_Operations (Parent_Type) then
9532 Set_Derived_Type_Link (Parent_Base, Derived_Type);
9535 -- If the parent type is a private subtype, the convention on the base
9536 -- type may be set in the private part, and not propagated to the
9537 -- subtype until later, so we obtain the convention from the base type.
9539 Set_Convention (Derived_Type, Convention (Parent_Base));
9541 -- Set SSO default for record or array type
9543 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
9544 and then Is_Base_Type (Derived_Type)
9546 Set_Default_SSO (Derived_Type);
9549 -- A derived type inherits the Default_Initial_Condition pragma coming
9550 -- from any parent type within the derivation chain.
9552 if Has_DIC (Parent_Type) then
9553 Set_Has_Inherited_DIC (Derived_Type);
9556 -- A derived type inherits any class-wide invariants coming from a
9557 -- parent type or an interface. Note that the invariant procedure of
9558 -- the parent type should not be inherited because the derived type may
9559 -- define invariants of its own.
9561 if not Is_Interface (Derived_Type) then
9562 if Has_Inherited_Invariants (Parent_Type)
9563 or else Has_Inheritable_Invariants (Parent_Type)
9565 Set_Has_Inherited_Invariants (Derived_Type);
9567 elsif Is_Concurrent_Type (Derived_Type)
9568 or else Is_Tagged_Type (Derived_Type)
9573 Iface_Elmt : Elmt_Id;
9578 Ifaces_List => Ifaces,
9579 Exclude_Parents => True);
9581 if Present (Ifaces) then
9582 Iface_Elmt := First_Elmt (Ifaces);
9583 while Present (Iface_Elmt) loop
9584 Iface := Node (Iface_Elmt);
9586 if Has_Inheritable_Invariants (Iface) then
9587 Set_Has_Inherited_Invariants (Derived_Type);
9591 Next_Elmt (Iface_Elmt);
9598 -- We similarly inherit predicates. Note that for scalar derived types
9599 -- the predicate is inherited from the first subtype, and not from its
9600 -- (anonymous) base type.
9602 if Has_Predicates (Parent_Type)
9603 or else Has_Predicates (First_Subtype (Parent_Type))
9605 Set_Has_Predicates (Derived_Type);
9608 -- The derived type inherits representation clauses from the parent
9609 -- type, and from any interfaces.
9611 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
9614 Iface : Node_Id := First (Abstract_Interface_List (Derived_Type));
9616 while Present (Iface) loop
9617 Inherit_Rep_Item_Chain (Derived_Type, Entity (Iface));
9622 -- If the parent type has delayed rep aspects, then mark the derived
9623 -- type as possibly inheriting a delayed rep aspect.
9625 if Has_Delayed_Rep_Aspects (Parent_Type) then
9626 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9629 -- A derived type becomes Ghost when its parent type is also Ghost
9630 -- (SPARK RM 6.9(9)). Note that the Ghost-related attributes are not
9631 -- directly inherited because the Ghost policy in effect may differ.
9633 if Is_Ghost_Entity (Parent_Type) then
9634 Set_Is_Ghost_Entity (Derived_Type);
9637 -- Type dependent processing
9639 case Ekind (Parent_Type) is
9640 when Numeric_Kind =>
9641 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9644 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9646 when Class_Wide_Kind
9650 Build_Derived_Record_Type
9651 (N, Parent_Type, Derived_Type, Derive_Subps);
9654 when Enumeration_Kind =>
9655 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9658 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9660 when Incomplete_Or_Private_Kind =>
9661 Build_Derived_Private_Type
9662 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9664 -- For discriminated types, the derivation includes deriving
9665 -- primitive operations. For others it is done below.
9667 if Is_Tagged_Type (Parent_Type)
9668 or else Has_Discriminants (Parent_Type)
9669 or else (Present (Full_View (Parent_Type))
9670 and then Has_Discriminants (Full_View (Parent_Type)))
9675 when Concurrent_Kind =>
9676 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9679 raise Program_Error;
9682 -- Nothing more to do if some error occurred
9684 if Etype (Derived_Type) = Any_Type then
9688 -- Set delayed freeze and then derive subprograms, we need to do this
9689 -- in this order so that derived subprograms inherit the derived freeze
9692 Set_Has_Delayed_Freeze (Derived_Type);
9694 if Derive_Subps then
9695 Derive_Subprograms (Parent_Type, Derived_Type);
9698 Set_Has_Primitive_Operations
9699 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9700 end Build_Derived_Type;
9702 -----------------------
9703 -- Build_Discriminal --
9704 -----------------------
9706 procedure Build_Discriminal (Discrim : Entity_Id) is
9707 D_Minal : Entity_Id;
9708 CR_Disc : Entity_Id;
9711 -- A discriminal has the same name as the discriminant
9713 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9715 Set_Ekind (D_Minal, E_In_Parameter);
9716 Set_Mechanism (D_Minal, Default_Mechanism);
9717 Set_Etype (D_Minal, Etype (Discrim));
9718 Set_Scope (D_Minal, Current_Scope);
9719 Set_Parent (D_Minal, Parent (Discrim));
9721 Set_Discriminal (Discrim, D_Minal);
9722 Set_Discriminal_Link (D_Minal, Discrim);
9724 -- For task types, build at once the discriminants of the corresponding
9725 -- record, which are needed if discriminants are used in entry defaults
9726 -- and in family bounds.
9728 if Is_Concurrent_Type (Current_Scope)
9730 Is_Limited_Type (Current_Scope)
9732 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9734 Set_Ekind (CR_Disc, E_In_Parameter);
9735 Set_Mechanism (CR_Disc, Default_Mechanism);
9736 Set_Etype (CR_Disc, Etype (Discrim));
9737 Set_Scope (CR_Disc, Current_Scope);
9738 Set_Discriminal_Link (CR_Disc, Discrim);
9739 Set_CR_Discriminant (Discrim, CR_Disc);
9741 end Build_Discriminal;
9743 ------------------------------------
9744 -- Build_Discriminant_Constraints --
9745 ------------------------------------
9747 function Build_Discriminant_Constraints
9750 Derived_Def : Boolean := False) return Elist_Id
9752 C : constant Node_Id := Constraint (Def);
9753 Nb_Discr : constant Nat := Number_Discriminants (T);
9755 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9756 -- Saves the expression corresponding to a given discriminant in T
9758 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9759 -- Return the Position number within array Discr_Expr of a discriminant
9760 -- D within the discriminant list of the discriminated type T.
9762 procedure Process_Discriminant_Expression
9765 -- If this is a discriminant constraint on a partial view, do not
9766 -- generate an overflow check on the discriminant expression. The check
9767 -- will be generated when constraining the full view. Otherwise the
9768 -- backend creates duplicate symbols for the temporaries corresponding
9769 -- to the expressions to be checked, causing spurious assembler errors.
9775 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9779 Disc := First_Discriminant (T);
9780 for J in Discr_Expr'Range loop
9785 Next_Discriminant (Disc);
9788 -- Note: Since this function is called on discriminants that are
9789 -- known to belong to the discriminated type, falling through the
9790 -- loop with no match signals an internal compiler error.
9792 raise Program_Error;
9795 -------------------------------------
9796 -- Process_Discriminant_Expression --
9797 -------------------------------------
9799 procedure Process_Discriminant_Expression
9803 BDT : constant Entity_Id := Base_Type (Etype (D));
9806 -- If this is a discriminant constraint on a partial view, do
9807 -- not generate an overflow on the discriminant expression. The
9808 -- check will be generated when constraining the full view.
9810 if Is_Private_Type (T)
9811 and then Present (Full_View (T))
9813 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9815 Analyze_And_Resolve (Expr, BDT);
9817 end Process_Discriminant_Expression;
9819 -- Declarations local to Build_Discriminant_Constraints
9823 Elist : constant Elist_Id := New_Elmt_List;
9831 Discrim_Present : Boolean := False;
9833 -- Start of processing for Build_Discriminant_Constraints
9836 -- The following loop will process positional associations only.
9837 -- For a positional association, the (single) discriminant is
9838 -- implicitly specified by position, in textual order (RM 3.7.2).
9840 Discr := First_Discriminant (T);
9841 Constr := First (Constraints (C));
9842 for D in Discr_Expr'Range loop
9843 exit when Nkind (Constr) = N_Discriminant_Association;
9846 Error_Msg_N ("too few discriminants given in constraint", C);
9847 return New_Elmt_List;
9849 elsif Nkind (Constr) = N_Range
9850 or else (Nkind (Constr) = N_Attribute_Reference
9851 and then Attribute_Name (Constr) = Name_Range)
9854 ("a range is not a valid discriminant constraint", Constr);
9855 Discr_Expr (D) := Error;
9858 Process_Discriminant_Expression (Constr, Discr);
9859 Discr_Expr (D) := Constr;
9862 Next_Discriminant (Discr);
9866 if No (Discr) and then Present (Constr) then
9867 Error_Msg_N ("too many discriminants given in constraint", Constr);
9868 return New_Elmt_List;
9871 -- Named associations can be given in any order, but if both positional
9872 -- and named associations are used in the same discriminant constraint,
9873 -- then positional associations must occur first, at their normal
9874 -- position. Hence once a named association is used, the rest of the
9875 -- discriminant constraint must use only named associations.
9877 while Present (Constr) loop
9879 -- Positional association forbidden after a named association
9881 if Nkind (Constr) /= N_Discriminant_Association then
9882 Error_Msg_N ("positional association follows named one", Constr);
9883 return New_Elmt_List;
9885 -- Otherwise it is a named association
9888 -- E records the type of the discriminants in the named
9889 -- association. All the discriminants specified in the same name
9890 -- association must have the same type.
9894 -- Search the list of discriminants in T to see if the simple name
9895 -- given in the constraint matches any of them.
9897 Id := First (Selector_Names (Constr));
9898 while Present (Id) loop
9901 -- If Original_Discriminant is present, we are processing a
9902 -- generic instantiation and this is an instance node. We need
9903 -- to find the name of the corresponding discriminant in the
9904 -- actual record type T and not the name of the discriminant in
9905 -- the generic formal. Example:
9908 -- type G (D : int) is private;
9910 -- subtype W is G (D => 1);
9912 -- type Rec (X : int) is record ... end record;
9913 -- package Q is new P (G => Rec);
9915 -- At the point of the instantiation, formal type G is Rec
9916 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9917 -- which really looks like "subtype W is Rec (D => 1);" at
9918 -- the point of instantiation, we want to find the discriminant
9919 -- that corresponds to D in Rec, i.e. X.
9921 if Present (Original_Discriminant (Id))
9922 and then In_Instance
9924 Discr := Find_Corresponding_Discriminant (Id, T);
9928 Discr := First_Discriminant (T);
9929 while Present (Discr) loop
9930 if Chars (Discr) = Chars (Id) then
9935 Next_Discriminant (Discr);
9939 Error_Msg_N ("& does not match any discriminant", Id);
9940 return New_Elmt_List;
9942 -- If the parent type is a generic formal, preserve the
9943 -- name of the discriminant for subsequent instances.
9944 -- see comment at the beginning of this if statement.
9946 elsif Is_Generic_Type (Root_Type (T)) then
9947 Set_Original_Discriminant (Id, Discr);
9951 Position := Pos_Of_Discr (T, Discr);
9953 if Present (Discr_Expr (Position)) then
9954 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9957 -- Each discriminant specified in the same named association
9958 -- must be associated with a separate copy of the
9959 -- corresponding expression.
9961 if Present (Next (Id)) then
9962 Expr := New_Copy_Tree (Expression (Constr));
9963 Set_Parent (Expr, Parent (Expression (Constr)));
9965 Expr := Expression (Constr);
9968 Discr_Expr (Position) := Expr;
9969 Process_Discriminant_Expression (Expr, Discr);
9972 -- A discriminant association with more than one discriminant
9973 -- name is only allowed if the named discriminants are all of
9974 -- the same type (RM 3.7.1(8)).
9977 E := Base_Type (Etype (Discr));
9979 elsif Base_Type (Etype (Discr)) /= E then
9981 ("all discriminants in an association " &
9982 "must have the same type", Id);
9992 -- A discriminant constraint must provide exactly one value for each
9993 -- discriminant of the type (RM 3.7.1(8)).
9995 for J in Discr_Expr'Range loop
9996 if No (Discr_Expr (J)) then
9997 Error_Msg_N ("too few discriminants given in constraint", C);
9998 return New_Elmt_List;
10002 -- Determine if there are discriminant expressions in the constraint
10004 for J in Discr_Expr'Range loop
10005 if Denotes_Discriminant
10006 (Discr_Expr (J), Check_Concurrent => True)
10008 Discrim_Present := True;
10012 -- Build an element list consisting of the expressions given in the
10013 -- discriminant constraint and apply the appropriate checks. The list
10014 -- is constructed after resolving any named discriminant associations
10015 -- and therefore the expressions appear in the textual order of the
10018 Discr := First_Discriminant (T);
10019 for J in Discr_Expr'Range loop
10020 if Discr_Expr (J) /= Error then
10021 Append_Elmt (Discr_Expr (J), Elist);
10023 -- If any of the discriminant constraints is given by a
10024 -- discriminant and we are in a derived type declaration we
10025 -- have a discriminant renaming. Establish link between new
10026 -- and old discriminant. The new discriminant has an implicit
10027 -- dereference if the old one does.
10029 if Denotes_Discriminant (Discr_Expr (J)) then
10030 if Derived_Def then
10032 New_Discr : constant Entity_Id := Entity (Discr_Expr (J));
10035 Set_Corresponding_Discriminant (New_Discr, Discr);
10036 Set_Has_Implicit_Dereference (New_Discr,
10037 Has_Implicit_Dereference (Discr));
10041 -- Force the evaluation of non-discriminant expressions.
10042 -- If we have found a discriminant in the constraint 3.4(26)
10043 -- and 3.8(18) demand that no range checks are performed are
10044 -- after evaluation. If the constraint is for a component
10045 -- definition that has a per-object constraint, expressions are
10046 -- evaluated but not checked either. In all other cases perform
10050 if Discrim_Present then
10053 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
10054 and then Has_Per_Object_Constraint
10055 (Defining_Identifier (Parent (Parent (Def))))
10059 elsif Is_Access_Type (Etype (Discr)) then
10060 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
10063 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
10066 Force_Evaluation (Discr_Expr (J));
10069 -- Check that the designated type of an access discriminant's
10070 -- expression is not a class-wide type unless the discriminant's
10071 -- designated type is also class-wide.
10073 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
10074 and then not Is_Class_Wide_Type
10075 (Designated_Type (Etype (Discr)))
10076 and then Etype (Discr_Expr (J)) /= Any_Type
10077 and then Is_Class_Wide_Type
10078 (Designated_Type (Etype (Discr_Expr (J))))
10080 Wrong_Type (Discr_Expr (J), Etype (Discr));
10082 elsif Is_Access_Type (Etype (Discr))
10083 and then not Is_Access_Constant (Etype (Discr))
10084 and then Is_Access_Type (Etype (Discr_Expr (J)))
10085 and then Is_Access_Constant (Etype (Discr_Expr (J)))
10088 ("constraint for discriminant& must be access to variable",
10093 Next_Discriminant (Discr);
10097 end Build_Discriminant_Constraints;
10099 ---------------------------------
10100 -- Build_Discriminated_Subtype --
10101 ---------------------------------
10103 procedure Build_Discriminated_Subtype
10105 Def_Id : Entity_Id;
10107 Related_Nod : Node_Id;
10108 For_Access : Boolean := False)
10110 Has_Discrs : constant Boolean := Has_Discriminants (T);
10111 Constrained : constant Boolean :=
10113 and then not Is_Empty_Elmt_List (Elist)
10114 and then not Is_Class_Wide_Type (T))
10115 or else Is_Constrained (T);
10118 if Ekind (T) = E_Record_Type then
10120 Set_Ekind (Def_Id, E_Private_Subtype);
10121 Set_Is_For_Access_Subtype (Def_Id, True);
10123 Set_Ekind (Def_Id, E_Record_Subtype);
10126 -- Inherit preelaboration flag from base, for types for which it
10127 -- may have been set: records, private types, protected types.
10129 Set_Known_To_Have_Preelab_Init
10130 (Def_Id, Known_To_Have_Preelab_Init (T));
10132 elsif Ekind (T) = E_Task_Type then
10133 Set_Ekind (Def_Id, E_Task_Subtype);
10135 elsif Ekind (T) = E_Protected_Type then
10136 Set_Ekind (Def_Id, E_Protected_Subtype);
10137 Set_Known_To_Have_Preelab_Init
10138 (Def_Id, Known_To_Have_Preelab_Init (T));
10140 elsif Is_Private_Type (T) then
10141 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
10142 Set_Known_To_Have_Preelab_Init
10143 (Def_Id, Known_To_Have_Preelab_Init (T));
10145 -- Private subtypes may have private dependents
10147 Set_Private_Dependents (Def_Id, New_Elmt_List);
10149 elsif Is_Class_Wide_Type (T) then
10150 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
10153 -- Incomplete type. Attach subtype to list of dependents, to be
10154 -- completed with full view of parent type, unless is it the
10155 -- designated subtype of a record component within an init_proc.
10156 -- This last case arises for a component of an access type whose
10157 -- designated type is incomplete (e.g. a Taft Amendment type).
10158 -- The designated subtype is within an inner scope, and needs no
10159 -- elaboration, because only the access type is needed in the
10160 -- initialization procedure.
10162 if Ekind (T) = E_Incomplete_Type then
10163 Set_Ekind (Def_Id, E_Incomplete_Subtype);
10165 Set_Ekind (Def_Id, Ekind (T));
10168 if For_Access and then Within_Init_Proc then
10171 Append_Elmt (Def_Id, Private_Dependents (T));
10175 Set_Etype (Def_Id, T);
10176 Init_Size_Align (Def_Id);
10177 Set_Has_Discriminants (Def_Id, Has_Discrs);
10178 Set_Is_Constrained (Def_Id, Constrained);
10180 Set_First_Entity (Def_Id, First_Entity (T));
10181 Set_Last_Entity (Def_Id, Last_Entity (T));
10182 Set_Has_Implicit_Dereference
10183 (Def_Id, Has_Implicit_Dereference (T));
10184 Set_Has_Pragma_Unreferenced_Objects
10185 (Def_Id, Has_Pragma_Unreferenced_Objects (T));
10187 -- If the subtype is the completion of a private declaration, there may
10188 -- have been representation clauses for the partial view, and they must
10189 -- be preserved. Build_Derived_Type chains the inherited clauses with
10190 -- the ones appearing on the extension. If this comes from a subtype
10191 -- declaration, all clauses are inherited.
10193 if No (First_Rep_Item (Def_Id)) then
10194 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10197 if Is_Tagged_Type (T) then
10198 Set_Is_Tagged_Type (Def_Id);
10199 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
10200 Make_Class_Wide_Type (Def_Id);
10203 Set_Stored_Constraint (Def_Id, No_Elist);
10206 Set_Discriminant_Constraint (Def_Id, Elist);
10207 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
10210 if Is_Tagged_Type (T) then
10212 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
10213 -- concurrent record type (which has the list of primitive
10216 if Ada_Version >= Ada_2005
10217 and then Is_Concurrent_Type (T)
10219 Set_Corresponding_Record_Type (Def_Id,
10220 Corresponding_Record_Type (T));
10222 Set_Direct_Primitive_Operations (Def_Id,
10223 Direct_Primitive_Operations (T));
10226 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
10229 -- Subtypes introduced by component declarations do not need to be
10230 -- marked as delayed, and do not get freeze nodes, because the semantics
10231 -- verifies that the parents of the subtypes are frozen before the
10232 -- enclosing record is frozen.
10234 if not Is_Type (Scope (Def_Id)) then
10235 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10237 if Is_Private_Type (T)
10238 and then Present (Full_View (T))
10240 Conditional_Delay (Def_Id, Full_View (T));
10242 Conditional_Delay (Def_Id, T);
10246 if Is_Record_Type (T) then
10247 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
10250 and then not Is_Empty_Elmt_List (Elist)
10251 and then not For_Access
10253 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
10254 elsif not For_Access then
10255 Set_Cloned_Subtype (Def_Id, T);
10258 end Build_Discriminated_Subtype;
10260 ---------------------------
10261 -- Build_Itype_Reference --
10262 ---------------------------
10264 procedure Build_Itype_Reference
10268 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
10271 -- Itype references are only created for use by the back-end
10273 if Inside_A_Generic then
10276 Set_Itype (IR, Ityp);
10278 -- If Nod is a library unit entity, then Insert_After won't work,
10279 -- because Nod is not a member of any list. Therefore, we use
10280 -- Add_Global_Declaration in this case. This can happen if we have a
10281 -- build-in-place library function.
10283 if (Nkind (Nod) in N_Entity
10284 and then Is_Compilation_Unit (Nod))
10286 (Nkind (Nod) = N_Defining_Program_Unit_Name
10287 and then Is_Compilation_Unit (Defining_Identifier (Nod)))
10289 Add_Global_Declaration (IR);
10291 Insert_After (Nod, IR);
10294 end Build_Itype_Reference;
10296 ------------------------
10297 -- Build_Scalar_Bound --
10298 ------------------------
10300 function Build_Scalar_Bound
10303 Der_T : Entity_Id) return Node_Id
10305 New_Bound : Entity_Id;
10308 -- Note: not clear why this is needed, how can the original bound
10309 -- be unanalyzed at this point? and if it is, what business do we
10310 -- have messing around with it? and why is the base type of the
10311 -- parent type the right type for the resolution. It probably is
10312 -- not. It is OK for the new bound we are creating, but not for
10313 -- the old one??? Still if it never happens, no problem.
10315 Analyze_And_Resolve (Bound, Base_Type (Par_T));
10317 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
10318 New_Bound := New_Copy (Bound);
10319 Set_Etype (New_Bound, Der_T);
10320 Set_Analyzed (New_Bound);
10322 elsif Is_Entity_Name (Bound) then
10323 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
10325 -- The following is almost certainly wrong. What business do we have
10326 -- relocating a node (Bound) that is presumably still attached to
10327 -- the tree elsewhere???
10330 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
10333 Set_Etype (New_Bound, Der_T);
10335 end Build_Scalar_Bound;
10337 --------------------------------
10338 -- Build_Underlying_Full_View --
10339 --------------------------------
10341 procedure Build_Underlying_Full_View
10346 Loc : constant Source_Ptr := Sloc (N);
10347 Subt : constant Entity_Id :=
10348 Make_Defining_Identifier
10349 (Loc, New_External_Name (Chars (Typ), 'S'));
10356 procedure Set_Discriminant_Name (Id : Node_Id);
10357 -- If the derived type has discriminants, they may rename discriminants
10358 -- of the parent. When building the full view of the parent, we need to
10359 -- recover the names of the original discriminants if the constraint is
10360 -- given by named associations.
10362 ---------------------------
10363 -- Set_Discriminant_Name --
10364 ---------------------------
10366 procedure Set_Discriminant_Name (Id : Node_Id) is
10370 Set_Original_Discriminant (Id, Empty);
10372 if Has_Discriminants (Typ) then
10373 Disc := First_Discriminant (Typ);
10374 while Present (Disc) loop
10375 if Chars (Disc) = Chars (Id)
10376 and then Present (Corresponding_Discriminant (Disc))
10378 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
10380 Next_Discriminant (Disc);
10383 end Set_Discriminant_Name;
10385 -- Start of processing for Build_Underlying_Full_View
10388 if Nkind (N) = N_Full_Type_Declaration then
10389 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
10391 elsif Nkind (N) = N_Subtype_Declaration then
10392 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
10394 elsif Nkind (N) = N_Component_Declaration then
10397 (Constraint (Subtype_Indication (Component_Definition (N))));
10400 raise Program_Error;
10403 C := First (Constraints (Constr));
10404 while Present (C) loop
10405 if Nkind (C) = N_Discriminant_Association then
10406 Id := First (Selector_Names (C));
10407 while Present (Id) loop
10408 Set_Discriminant_Name (Id);
10417 Make_Subtype_Declaration (Loc,
10418 Defining_Identifier => Subt,
10419 Subtype_Indication =>
10420 Make_Subtype_Indication (Loc,
10421 Subtype_Mark => New_Occurrence_Of (Par, Loc),
10422 Constraint => New_Copy_Tree (Constr)));
10424 -- If this is a component subtype for an outer itype, it is not
10425 -- a list member, so simply set the parent link for analysis: if
10426 -- the enclosing type does not need to be in a declarative list,
10427 -- neither do the components.
10429 if Is_List_Member (N)
10430 and then Nkind (N) /= N_Component_Declaration
10432 Insert_Before (N, Indic);
10434 Set_Parent (Indic, Parent (N));
10438 Set_Underlying_Full_View (Typ, Full_View (Subt));
10439 Set_Is_Underlying_Full_View (Full_View (Subt));
10440 end Build_Underlying_Full_View;
10442 -------------------------------
10443 -- Check_Abstract_Overriding --
10444 -------------------------------
10446 procedure Check_Abstract_Overriding (T : Entity_Id) is
10447 Alias_Subp : Entity_Id;
10449 Op_List : Elist_Id;
10451 Type_Def : Node_Id;
10453 procedure Check_Pragma_Implemented (Subp : Entity_Id);
10454 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
10455 -- which has pragma Implemented already set. Check whether Subp's entity
10456 -- kind conforms to the implementation kind of the overridden routine.
10458 procedure Check_Pragma_Implemented
10460 Iface_Subp : Entity_Id);
10461 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
10462 -- Iface_Subp and both entities have pragma Implemented already set on
10463 -- them. Check whether the two implementation kinds are conforming.
10465 procedure Inherit_Pragma_Implemented
10467 Iface_Subp : Entity_Id);
10468 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
10469 -- subprogram Iface_Subp which has been marked by pragma Implemented.
10470 -- Propagate the implementation kind of Iface_Subp to Subp.
10472 ------------------------------
10473 -- Check_Pragma_Implemented --
10474 ------------------------------
10476 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
10477 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
10478 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
10479 Subp_Alias : constant Entity_Id := Alias (Subp);
10480 Contr_Typ : Entity_Id;
10481 Impl_Subp : Entity_Id;
10484 -- Subp must have an alias since it is a hidden entity used to link
10485 -- an interface subprogram to its overriding counterpart.
10487 pragma Assert (Present (Subp_Alias));
10489 -- Handle aliases to synchronized wrappers
10491 Impl_Subp := Subp_Alias;
10493 if Is_Primitive_Wrapper (Impl_Subp) then
10494 Impl_Subp := Wrapped_Entity (Impl_Subp);
10497 -- Extract the type of the controlling formal
10499 Contr_Typ := Etype (First_Formal (Subp_Alias));
10501 if Is_Concurrent_Record_Type (Contr_Typ) then
10502 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
10505 -- An interface subprogram whose implementation kind is By_Entry must
10506 -- be implemented by an entry.
10508 if Impl_Kind = Name_By_Entry
10509 and then Ekind (Impl_Subp) /= E_Entry
10511 Error_Msg_Node_2 := Iface_Alias;
10513 ("type & must implement abstract subprogram & with an entry",
10514 Subp_Alias, Contr_Typ);
10516 elsif Impl_Kind = Name_By_Protected_Procedure then
10518 -- An interface subprogram whose implementation kind is By_
10519 -- Protected_Procedure cannot be implemented by a primitive
10520 -- procedure of a task type.
10522 if Ekind (Contr_Typ) /= E_Protected_Type then
10523 Error_Msg_Node_2 := Contr_Typ;
10525 ("interface subprogram & cannot be implemented by a " &
10526 "primitive procedure of task type &", Subp_Alias,
10529 -- An interface subprogram whose implementation kind is By_
10530 -- Protected_Procedure must be implemented by a procedure.
10532 elsif Ekind (Impl_Subp) /= E_Procedure then
10533 Error_Msg_Node_2 := Iface_Alias;
10535 ("type & must implement abstract subprogram & with a " &
10536 "procedure", Subp_Alias, Contr_Typ);
10538 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10539 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10541 Error_Msg_Name_1 := Impl_Kind;
10543 ("overriding operation& must have synchronization%",
10547 -- If primitive has Optional synchronization, overriding operation
10548 -- must match if it has an explicit synchronization..
10550 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10551 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10553 Error_Msg_Name_1 := Impl_Kind;
10555 ("overriding operation& must have syncrhonization%",
10558 end Check_Pragma_Implemented;
10560 ------------------------------
10561 -- Check_Pragma_Implemented --
10562 ------------------------------
10564 procedure Check_Pragma_Implemented
10566 Iface_Subp : Entity_Id)
10568 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10569 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
10572 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
10573 -- and overriding subprogram are different. In general this is an
10574 -- error except when the implementation kind of the overridden
10575 -- subprograms is By_Any or Optional.
10577 if Iface_Kind /= Subp_Kind
10578 and then Iface_Kind /= Name_By_Any
10579 and then Iface_Kind /= Name_Optional
10581 if Iface_Kind = Name_By_Entry then
10583 ("incompatible implementation kind, overridden subprogram " &
10584 "is marked By_Entry", Subp);
10587 ("incompatible implementation kind, overridden subprogram " &
10588 "is marked By_Protected_Procedure", Subp);
10591 end Check_Pragma_Implemented;
10593 --------------------------------
10594 -- Inherit_Pragma_Implemented --
10595 --------------------------------
10597 procedure Inherit_Pragma_Implemented
10599 Iface_Subp : Entity_Id)
10601 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10602 Loc : constant Source_Ptr := Sloc (Subp);
10603 Impl_Prag : Node_Id;
10606 -- Since the implementation kind is stored as a representation item
10607 -- rather than a flag, create a pragma node.
10611 Chars => Name_Implemented,
10612 Pragma_Argument_Associations => New_List (
10613 Make_Pragma_Argument_Association (Loc,
10614 Expression => New_Occurrence_Of (Subp, Loc)),
10616 Make_Pragma_Argument_Association (Loc,
10617 Expression => Make_Identifier (Loc, Iface_Kind))));
10619 -- The pragma doesn't need to be analyzed because it is internally
10620 -- built. It is safe to directly register it as a rep item since we
10621 -- are only interested in the characters of the implementation kind.
10623 Record_Rep_Item (Subp, Impl_Prag);
10624 end Inherit_Pragma_Implemented;
10626 -- Start of processing for Check_Abstract_Overriding
10629 Op_List := Primitive_Operations (T);
10631 -- Loop to check primitive operations
10633 Elmt := First_Elmt (Op_List);
10634 while Present (Elmt) loop
10635 Subp := Node (Elmt);
10636 Alias_Subp := Alias (Subp);
10638 -- Inherited subprograms are identified by the fact that they do not
10639 -- come from source, and the associated source location is the
10640 -- location of the first subtype of the derived type.
10642 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
10643 -- subprograms that "require overriding".
10645 -- Special exception, do not complain about failure to override the
10646 -- stream routines _Input and _Output, as well as the primitive
10647 -- operations used in dispatching selects since we always provide
10648 -- automatic overridings for these subprograms.
10650 -- The partial view of T may have been a private extension, for
10651 -- which inherited functions dispatching on result are abstract.
10652 -- If the full view is a null extension, there is no need for
10653 -- overriding in Ada 2005, but wrappers need to be built for them
10654 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10656 if Is_Null_Extension (T)
10657 and then Has_Controlling_Result (Subp)
10658 and then Ada_Version >= Ada_2005
10659 and then Present (Alias_Subp)
10660 and then not Comes_From_Source (Subp)
10661 and then not Is_Abstract_Subprogram (Alias_Subp)
10662 and then not Is_Access_Type (Etype (Subp))
10666 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10667 -- processing because this check is done with the aliased
10670 elsif Present (Interface_Alias (Subp)) then
10673 elsif (Is_Abstract_Subprogram (Subp)
10674 or else Requires_Overriding (Subp)
10676 (Has_Controlling_Result (Subp)
10677 and then Present (Alias_Subp)
10678 and then not Comes_From_Source (Subp)
10679 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10680 and then not Is_TSS (Subp, TSS_Stream_Input)
10681 and then not Is_TSS (Subp, TSS_Stream_Output)
10682 and then not Is_Abstract_Type (T)
10683 and then not Is_Predefined_Interface_Primitive (Subp)
10685 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10686 -- with abstract interface types because the check will be done
10687 -- with the aliased entity (otherwise we generate a duplicated
10690 and then not Present (Interface_Alias (Subp))
10692 if Present (Alias_Subp) then
10694 -- Only perform the check for a derived subprogram when the
10695 -- type has an explicit record extension. This avoids incorrect
10696 -- flagging of abstract subprograms for the case of a type
10697 -- without an extension that is derived from a formal type
10698 -- with a tagged actual (can occur within a private part).
10700 -- Ada 2005 (AI-391): In the case of an inherited function with
10701 -- a controlling result of the type, the rule does not apply if
10702 -- the type is a null extension (unless the parent function
10703 -- itself is abstract, in which case the function must still be
10704 -- be overridden). The expander will generate an overriding
10705 -- wrapper function calling the parent subprogram (see
10706 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10708 Type_Def := Type_Definition (Parent (T));
10710 if Nkind (Type_Def) = N_Derived_Type_Definition
10711 and then Present (Record_Extension_Part (Type_Def))
10713 (Ada_Version < Ada_2005
10714 or else not Is_Null_Extension (T)
10715 or else Ekind (Subp) = E_Procedure
10716 or else not Has_Controlling_Result (Subp)
10717 or else Is_Abstract_Subprogram (Alias_Subp)
10718 or else Requires_Overriding (Subp)
10719 or else Is_Access_Type (Etype (Subp)))
10721 -- Avoid reporting error in case of abstract predefined
10722 -- primitive inherited from interface type because the
10723 -- body of internally generated predefined primitives
10724 -- of tagged types are generated later by Freeze_Type
10726 if Is_Interface (Root_Type (T))
10727 and then Is_Abstract_Subprogram (Subp)
10728 and then Is_Predefined_Dispatching_Operation (Subp)
10729 and then not Comes_From_Source (Ultimate_Alias (Subp))
10733 -- A null extension is not obliged to override an inherited
10734 -- procedure subject to pragma Extensions_Visible with value
10735 -- False and at least one controlling OUT parameter
10736 -- (SPARK RM 6.1.7(6)).
10738 elsif Is_Null_Extension (T)
10739 and then Is_EVF_Procedure (Subp)
10745 ("type must be declared abstract or & overridden",
10748 -- Traverse the whole chain of aliased subprograms to
10749 -- complete the error notification. This is especially
10750 -- useful for traceability of the chain of entities when
10751 -- the subprogram corresponds with an interface
10752 -- subprogram (which may be defined in another package).
10754 if Present (Alias_Subp) then
10760 while Present (Alias (E)) loop
10762 -- Avoid reporting redundant errors on entities
10763 -- inherited from interfaces
10765 if Sloc (E) /= Sloc (T) then
10766 Error_Msg_Sloc := Sloc (E);
10768 ("\& has been inherited #", T, Subp);
10774 Error_Msg_Sloc := Sloc (E);
10776 -- AI05-0068: report if there is an overriding
10777 -- non-abstract subprogram that is invisible.
10780 and then not Is_Abstract_Subprogram (E)
10783 ("\& subprogram# is not visible",
10786 -- Clarify the case where a non-null extension must
10787 -- override inherited procedure subject to pragma
10788 -- Extensions_Visible with value False and at least
10789 -- one controlling OUT param.
10791 elsif Is_EVF_Procedure (E) then
10793 ("\& # is subject to Extensions_Visible False",
10798 ("\& has been inherited from subprogram #",
10805 -- Ada 2005 (AI-345): Protected or task type implementing
10806 -- abstract interfaces.
10808 elsif Is_Concurrent_Record_Type (T)
10809 and then Present (Interfaces (T))
10811 -- There is no need to check here RM 9.4(11.9/3) since we
10812 -- are processing the corresponding record type and the
10813 -- mode of the overriding subprograms was verified by
10814 -- Check_Conformance when the corresponding concurrent
10815 -- type declaration was analyzed.
10818 ("interface subprogram & must be overridden", T, Subp);
10820 -- Examine primitive operations of synchronized type to find
10821 -- homonyms that have the wrong profile.
10827 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10828 while Present (Prim) loop
10829 if Chars (Prim) = Chars (Subp) then
10831 ("profile is not type conformant with prefixed "
10832 & "view profile of inherited operation&",
10836 Next_Entity (Prim);
10842 Error_Msg_Node_2 := T;
10844 ("abstract subprogram& not allowed for type&", Subp);
10846 -- Also post unconditional warning on the type (unconditional
10847 -- so that if there are more than one of these cases, we get
10848 -- them all, and not just the first one).
10850 Error_Msg_Node_2 := Subp;
10851 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10854 -- A subprogram subject to pragma Extensions_Visible with value
10855 -- "True" cannot override a subprogram subject to the same pragma
10856 -- with value "False" (SPARK RM 6.1.7(5)).
10858 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10859 and then Present (Overridden_Operation (Subp))
10860 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10861 Extensions_Visible_False
10863 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10865 ("subprogram & with Extensions_Visible True cannot override "
10866 & "subprogram # with Extensions_Visible False", Subp);
10869 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10871 -- Subp is an expander-generated procedure which maps an interface
10872 -- alias to a protected wrapper. The interface alias is flagged by
10873 -- pragma Implemented. Ensure that Subp is a procedure when the
10874 -- implementation kind is By_Protected_Procedure or an entry when
10877 if Ada_Version >= Ada_2012
10878 and then Is_Hidden (Subp)
10879 and then Present (Interface_Alias (Subp))
10880 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10882 Check_Pragma_Implemented (Subp);
10885 -- Subp is an interface primitive which overrides another interface
10886 -- primitive marked with pragma Implemented.
10888 if Ada_Version >= Ada_2012
10889 and then Present (Overridden_Operation (Subp))
10890 and then Has_Rep_Pragma
10891 (Overridden_Operation (Subp), Name_Implemented)
10893 -- If the overriding routine is also marked by Implemented, check
10894 -- that the two implementation kinds are conforming.
10896 if Has_Rep_Pragma (Subp, Name_Implemented) then
10897 Check_Pragma_Implemented
10899 Iface_Subp => Overridden_Operation (Subp));
10901 -- Otherwise the overriding routine inherits the implementation
10902 -- kind from the overridden subprogram.
10905 Inherit_Pragma_Implemented
10907 Iface_Subp => Overridden_Operation (Subp));
10911 -- If the operation is a wrapper for a synchronized primitive, it
10912 -- may be called indirectly through a dispatching select. We assume
10913 -- that it will be referenced elsewhere indirectly, and suppress
10914 -- warnings about an unused entity.
10916 if Is_Primitive_Wrapper (Subp)
10917 and then Present (Wrapped_Entity (Subp))
10919 Set_Referenced (Wrapped_Entity (Subp));
10924 end Check_Abstract_Overriding;
10926 ------------------------------------------------
10927 -- Check_Access_Discriminant_Requires_Limited --
10928 ------------------------------------------------
10930 procedure Check_Access_Discriminant_Requires_Limited
10935 -- A discriminant_specification for an access discriminant shall appear
10936 -- only in the declaration for a task or protected type, or for a type
10937 -- with the reserved word 'limited' in its definition or in one of its
10938 -- ancestors (RM 3.7(10)).
10940 -- AI-0063: The proper condition is that type must be immutably limited,
10941 -- or else be a partial view.
10943 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10944 if Is_Limited_View (Current_Scope)
10946 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10947 and then Limited_Present (Parent (Current_Scope)))
10953 ("access discriminants allowed only for limited types", Loc);
10956 end Check_Access_Discriminant_Requires_Limited;
10958 -----------------------------------
10959 -- Check_Aliased_Component_Types --
10960 -----------------------------------
10962 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10966 -- ??? Also need to check components of record extensions, but not
10967 -- components of protected types (which are always limited).
10969 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10970 -- types to be unconstrained. This is safe because it is illegal to
10971 -- create access subtypes to such types with explicit discriminant
10974 if not Is_Limited_Type (T) then
10975 if Ekind (T) = E_Record_Type then
10976 C := First_Component (T);
10977 while Present (C) loop
10979 and then Has_Discriminants (Etype (C))
10980 and then not Is_Constrained (Etype (C))
10981 and then not In_Instance_Body
10982 and then Ada_Version < Ada_2005
10985 ("aliased component must be constrained (RM 3.6(11))",
10989 Next_Component (C);
10992 elsif Ekind (T) = E_Array_Type then
10993 if Has_Aliased_Components (T)
10994 and then Has_Discriminants (Component_Type (T))
10995 and then not Is_Constrained (Component_Type (T))
10996 and then not In_Instance_Body
10997 and then Ada_Version < Ada_2005
11000 ("aliased component type must be constrained (RM 3.6(11))",
11005 end Check_Aliased_Component_Types;
11007 ---------------------------------------
11008 -- Check_Anonymous_Access_Components --
11009 ---------------------------------------
11011 procedure Check_Anonymous_Access_Components
11012 (Typ_Decl : Node_Id;
11015 Comp_List : Node_Id)
11017 Loc : constant Source_Ptr := Sloc (Typ_Decl);
11018 Anon_Access : Entity_Id;
11021 Comp_Def : Node_Id;
11023 Type_Def : Node_Id;
11025 procedure Build_Incomplete_Type_Declaration;
11026 -- If the record type contains components that include an access to the
11027 -- current record, then create an incomplete type declaration for the
11028 -- record, to be used as the designated type of the anonymous access.
11029 -- This is done only once, and only if there is no previous partial
11030 -- view of the type.
11032 function Designates_T (Subt : Node_Id) return Boolean;
11033 -- Check whether a node designates the enclosing record type, or 'Class
11036 function Mentions_T (Acc_Def : Node_Id) return Boolean;
11037 -- Check whether an access definition includes a reference to
11038 -- the enclosing record type. The reference can be a subtype mark
11039 -- in the access definition itself, a 'Class attribute reference, or
11040 -- recursively a reference appearing in a parameter specification
11041 -- or result definition of an access_to_subprogram definition.
11043 --------------------------------------
11044 -- Build_Incomplete_Type_Declaration --
11045 --------------------------------------
11047 procedure Build_Incomplete_Type_Declaration is
11052 -- Is_Tagged indicates whether the type is tagged. It is tagged if
11053 -- it's "is new ... with record" or else "is tagged record ...".
11055 Is_Tagged : constant Boolean :=
11056 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
11058 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
11060 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
11061 and then Tagged_Present (Type_Definition (Typ_Decl)));
11064 -- If there is a previous partial view, no need to create a new one
11065 -- If the partial view, given by Prev, is incomplete, If Prev is
11066 -- a private declaration, full declaration is flagged accordingly.
11068 if Prev /= Typ then
11070 Make_Class_Wide_Type (Prev);
11071 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
11072 Set_Etype (Class_Wide_Type (Typ), Typ);
11077 elsif Has_Private_Declaration (Typ) then
11079 -- If we refer to T'Class inside T, and T is the completion of a
11080 -- private type, then make sure the class-wide type exists.
11083 Make_Class_Wide_Type (Typ);
11088 -- If there was a previous anonymous access type, the incomplete
11089 -- type declaration will have been created already.
11091 elsif Present (Current_Entity (Typ))
11092 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
11093 and then Full_View (Current_Entity (Typ)) = Typ
11096 and then Comes_From_Source (Current_Entity (Typ))
11097 and then not Is_Tagged_Type (Current_Entity (Typ))
11099 Make_Class_Wide_Type (Typ);
11101 ("incomplete view of tagged type should be declared tagged??",
11102 Parent (Current_Entity (Typ)));
11107 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
11108 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
11110 -- Type has already been inserted into the current scope. Remove
11111 -- it, and add incomplete declaration for type, so that subsequent
11112 -- anonymous access types can use it. The entity is unchained from
11113 -- the homonym list and from immediate visibility. After analysis,
11114 -- the entity in the incomplete declaration becomes immediately
11115 -- visible in the record declaration that follows.
11117 H := Current_Entity (Typ);
11120 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
11123 and then Homonym (H) /= Typ
11125 H := Homonym (Typ);
11128 Set_Homonym (H, Homonym (Typ));
11131 Insert_Before (Typ_Decl, Decl);
11133 Set_Full_View (Inc_T, Typ);
11137 -- Create a common class-wide type for both views, and set the
11138 -- Etype of the class-wide type to the full view.
11140 Make_Class_Wide_Type (Inc_T);
11141 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
11142 Set_Etype (Class_Wide_Type (Typ), Typ);
11145 end Build_Incomplete_Type_Declaration;
11151 function Designates_T (Subt : Node_Id) return Boolean is
11152 Type_Id : constant Name_Id := Chars (Typ);
11154 function Names_T (Nam : Node_Id) return Boolean;
11155 -- The record type has not been introduced in the current scope
11156 -- yet, so we must examine the name of the type itself, either
11157 -- an identifier T, or an expanded name of the form P.T, where
11158 -- P denotes the current scope.
11164 function Names_T (Nam : Node_Id) return Boolean is
11166 if Nkind (Nam) = N_Identifier then
11167 return Chars (Nam) = Type_Id;
11169 elsif Nkind (Nam) = N_Selected_Component then
11170 if Chars (Selector_Name (Nam)) = Type_Id then
11171 if Nkind (Prefix (Nam)) = N_Identifier then
11172 return Chars (Prefix (Nam)) = Chars (Current_Scope);
11174 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
11175 return Chars (Selector_Name (Prefix (Nam))) =
11176 Chars (Current_Scope);
11190 -- Start of processing for Designates_T
11193 if Nkind (Subt) = N_Identifier then
11194 return Chars (Subt) = Type_Id;
11196 -- Reference can be through an expanded name which has not been
11197 -- analyzed yet, and which designates enclosing scopes.
11199 elsif Nkind (Subt) = N_Selected_Component then
11200 if Names_T (Subt) then
11203 -- Otherwise it must denote an entity that is already visible.
11204 -- The access definition may name a subtype of the enclosing
11205 -- type, if there is a previous incomplete declaration for it.
11208 Find_Selected_Component (Subt);
11210 Is_Entity_Name (Subt)
11211 and then Scope (Entity (Subt)) = Current_Scope
11213 (Chars (Base_Type (Entity (Subt))) = Type_Id
11215 (Is_Class_Wide_Type (Entity (Subt))
11217 Chars (Etype (Base_Type (Entity (Subt)))) =
11221 -- A reference to the current type may appear as the prefix of
11222 -- a 'Class attribute.
11224 elsif Nkind (Subt) = N_Attribute_Reference
11225 and then Attribute_Name (Subt) = Name_Class
11227 return Names_T (Prefix (Subt));
11238 function Mentions_T (Acc_Def : Node_Id) return Boolean is
11239 Param_Spec : Node_Id;
11241 Acc_Subprg : constant Node_Id :=
11242 Access_To_Subprogram_Definition (Acc_Def);
11245 if No (Acc_Subprg) then
11246 return Designates_T (Subtype_Mark (Acc_Def));
11249 -- Component is an access_to_subprogram: examine its formals,
11250 -- and result definition in the case of an access_to_function.
11252 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
11253 while Present (Param_Spec) loop
11254 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
11255 and then Mentions_T (Parameter_Type (Param_Spec))
11259 elsif Designates_T (Parameter_Type (Param_Spec)) then
11266 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
11267 if Nkind (Result_Definition (Acc_Subprg)) =
11268 N_Access_Definition
11270 return Mentions_T (Result_Definition (Acc_Subprg));
11272 return Designates_T (Result_Definition (Acc_Subprg));
11279 -- Start of processing for Check_Anonymous_Access_Components
11282 if No (Comp_List) then
11286 Comp := First (Component_Items (Comp_List));
11287 while Present (Comp) loop
11288 if Nkind (Comp) = N_Component_Declaration
11290 (Access_Definition (Component_Definition (Comp)))
11292 Mentions_T (Access_Definition (Component_Definition (Comp)))
11294 Comp_Def := Component_Definition (Comp);
11296 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
11298 Build_Incomplete_Type_Declaration;
11299 Anon_Access := Make_Temporary (Loc, 'S');
11301 -- Create a declaration for the anonymous access type: either
11302 -- an access_to_object or an access_to_subprogram.
11304 if Present (Acc_Def) then
11305 if Nkind (Acc_Def) = N_Access_Function_Definition then
11307 Make_Access_Function_Definition (Loc,
11308 Parameter_Specifications =>
11309 Parameter_Specifications (Acc_Def),
11310 Result_Definition => Result_Definition (Acc_Def));
11313 Make_Access_Procedure_Definition (Loc,
11314 Parameter_Specifications =>
11315 Parameter_Specifications (Acc_Def));
11320 Make_Access_To_Object_Definition (Loc,
11321 Subtype_Indication =>
11323 (Subtype_Mark (Access_Definition (Comp_Def))));
11325 Set_Constant_Present
11326 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
11328 (Type_Def, All_Present (Access_Definition (Comp_Def)));
11331 Set_Null_Exclusion_Present
11333 Null_Exclusion_Present (Access_Definition (Comp_Def)));
11336 Make_Full_Type_Declaration (Loc,
11337 Defining_Identifier => Anon_Access,
11338 Type_Definition => Type_Def);
11340 Insert_Before (Typ_Decl, Decl);
11343 -- If an access to subprogram, create the extra formals
11345 if Present (Acc_Def) then
11346 Create_Extra_Formals (Designated_Type (Anon_Access));
11348 -- If an access to object, preserve entity of designated type,
11349 -- for ASIS use, before rewriting the component definition.
11356 Desig := Entity (Subtype_Indication (Type_Def));
11358 -- If the access definition is to the current record,
11359 -- the visible entity at this point is an incomplete
11360 -- type. Retrieve the full view to simplify ASIS queries
11362 if Ekind (Desig) = E_Incomplete_Type then
11363 Desig := Full_View (Desig);
11367 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
11372 Make_Component_Definition (Loc,
11373 Subtype_Indication =>
11374 New_Occurrence_Of (Anon_Access, Loc)));
11376 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
11377 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
11379 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
11382 Set_Is_Local_Anonymous_Access (Anon_Access);
11388 if Present (Variant_Part (Comp_List)) then
11392 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
11393 while Present (V) loop
11394 Check_Anonymous_Access_Components
11395 (Typ_Decl, Typ, Prev, Component_List (V));
11396 Next_Non_Pragma (V);
11400 end Check_Anonymous_Access_Components;
11402 ----------------------
11403 -- Check_Completion --
11404 ----------------------
11406 procedure Check_Completion (Body_Id : Node_Id := Empty) is
11409 procedure Post_Error;
11410 -- Post error message for lack of completion for entity E
11416 procedure Post_Error is
11417 procedure Missing_Body;
11418 -- Output missing body message
11424 procedure Missing_Body is
11426 -- Spec is in same unit, so we can post on spec
11428 if In_Same_Source_Unit (Body_Id, E) then
11429 Error_Msg_N ("missing body for &", E);
11431 -- Spec is in a separate unit, so we have to post on the body
11434 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
11438 -- Start of processing for Post_Error
11441 if not Comes_From_Source (E) then
11442 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
11444 -- It may be an anonymous protected type created for a
11445 -- single variable. Post error on variable, if present.
11451 Var := First_Entity (Current_Scope);
11452 while Present (Var) loop
11453 exit when Etype (Var) = E
11454 and then Comes_From_Source (Var);
11459 if Present (Var) then
11466 -- If a generated entity has no completion, then either previous
11467 -- semantic errors have disabled the expansion phase, or else we had
11468 -- missing subunits, or else we are compiling without expansion,
11469 -- or else something is very wrong.
11471 if not Comes_From_Source (E) then
11473 (Serious_Errors_Detected > 0
11474 or else Configurable_Run_Time_Violations > 0
11475 or else Subunits_Missing
11476 or else not Expander_Active);
11479 -- Here for source entity
11482 -- Here if no body to post the error message, so we post the error
11483 -- on the declaration that has no completion. This is not really
11484 -- the right place to post it, think about this later ???
11486 if No (Body_Id) then
11487 if Is_Type (E) then
11489 ("missing full declaration for }", Parent (E), E);
11491 Error_Msg_NE ("missing body for &", Parent (E), E);
11494 -- Package body has no completion for a declaration that appears
11495 -- in the corresponding spec. Post error on the body, with a
11496 -- reference to the non-completed declaration.
11499 Error_Msg_Sloc := Sloc (E);
11501 if Is_Type (E) then
11502 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
11504 elsif Is_Overloadable (E)
11505 and then Current_Entity_In_Scope (E) /= E
11507 -- It may be that the completion is mistyped and appears as
11508 -- a distinct overloading of the entity.
11511 Candidate : constant Entity_Id :=
11512 Current_Entity_In_Scope (E);
11513 Decl : constant Node_Id :=
11514 Unit_Declaration_Node (Candidate);
11517 if Is_Overloadable (Candidate)
11518 and then Ekind (Candidate) = Ekind (E)
11519 and then Nkind (Decl) = N_Subprogram_Body
11520 and then Acts_As_Spec (Decl)
11522 Check_Type_Conformant (Candidate, E);
11538 Pack_Id : constant Entity_Id := Current_Scope;
11540 -- Start of processing for Check_Completion
11543 E := First_Entity (Pack_Id);
11544 while Present (E) loop
11545 if Is_Intrinsic_Subprogram (E) then
11548 -- The following situation requires special handling: a child unit
11549 -- that appears in the context clause of the body of its parent:
11551 -- procedure Parent.Child (...);
11553 -- with Parent.Child;
11554 -- package body Parent is
11556 -- Here Parent.Child appears as a local entity, but should not be
11557 -- flagged as requiring completion, because it is a compilation
11560 -- Ignore missing completion for a subprogram that does not come from
11561 -- source (including the _Call primitive operation of RAS types,
11562 -- which has to have the flag Comes_From_Source for other purposes):
11563 -- we assume that the expander will provide the missing completion.
11564 -- In case of previous errors, other expansion actions that provide
11565 -- bodies for null procedures with not be invoked, so inhibit message
11568 -- Note that E_Operator is not in the list that follows, because
11569 -- this kind is reserved for predefined operators, that are
11570 -- intrinsic and do not need completion.
11572 elsif Ekind_In (E, E_Function,
11574 E_Generic_Function,
11575 E_Generic_Procedure)
11577 if Has_Completion (E) then
11580 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
11583 elsif Is_Subprogram (E)
11584 and then (not Comes_From_Source (E)
11585 or else Chars (E) = Name_uCall)
11590 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
11594 elsif Nkind (Parent (E)) = N_Procedure_Specification
11595 and then Null_Present (Parent (E))
11596 and then Serious_Errors_Detected > 0
11604 elsif Is_Entry (E) then
11605 if not Has_Completion (E) and then
11606 (Ekind (Scope (E)) = E_Protected_Object
11607 or else Ekind (Scope (E)) = E_Protected_Type)
11612 elsif Is_Package_Or_Generic_Package (E) then
11613 if Unit_Requires_Body (E) then
11614 if not Has_Completion (E)
11615 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
11621 elsif not Is_Child_Unit (E) then
11622 May_Need_Implicit_Body (E);
11625 -- A formal incomplete type (Ada 2012) does not require a completion;
11626 -- other incomplete type declarations do.
11628 elsif Ekind (E) = E_Incomplete_Type
11629 and then No (Underlying_Type (E))
11630 and then not Is_Generic_Type (E)
11634 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
11635 and then not Has_Completion (E)
11639 -- A single task declared in the current scope is a constant, verify
11640 -- that the body of its anonymous type is in the same scope. If the
11641 -- task is defined elsewhere, this may be a renaming declaration for
11642 -- which no completion is needed.
11644 elsif Ekind (E) = E_Constant
11645 and then Ekind (Etype (E)) = E_Task_Type
11646 and then not Has_Completion (Etype (E))
11647 and then Scope (Etype (E)) = Current_Scope
11651 elsif Ekind (E) = E_Protected_Object
11652 and then not Has_Completion (Etype (E))
11656 elsif Ekind (E) = E_Record_Type then
11657 if Is_Tagged_Type (E) then
11658 Check_Abstract_Overriding (E);
11659 Check_Conventions (E);
11662 Check_Aliased_Component_Types (E);
11664 elsif Ekind (E) = E_Array_Type then
11665 Check_Aliased_Component_Types (E);
11671 end Check_Completion;
11673 ------------------------------------
11674 -- Check_CPP_Type_Has_No_Defaults --
11675 ------------------------------------
11677 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11678 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11683 -- Obtain the component list
11685 if Nkind (Tdef) = N_Record_Definition then
11686 Clist := Component_List (Tdef);
11687 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11688 Clist := Component_List (Record_Extension_Part (Tdef));
11691 -- Check all components to ensure no default expressions
11693 if Present (Clist) then
11694 Comp := First (Component_Items (Clist));
11695 while Present (Comp) loop
11696 if Present (Expression (Comp)) then
11698 ("component of imported 'C'P'P type cannot have "
11699 & "default expression", Expression (Comp));
11705 end Check_CPP_Type_Has_No_Defaults;
11707 ----------------------------
11708 -- Check_Delta_Expression --
11709 ----------------------------
11711 procedure Check_Delta_Expression (E : Node_Id) is
11713 if not (Is_Real_Type (Etype (E))) then
11714 Wrong_Type (E, Any_Real);
11716 elsif not Is_OK_Static_Expression (E) then
11717 Flag_Non_Static_Expr
11718 ("non-static expression used for delta value!", E);
11720 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11721 Error_Msg_N ("delta expression must be positive", E);
11727 -- If any of above errors occurred, then replace the incorrect
11728 -- expression by the real 0.1, which should prevent further errors.
11731 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11732 Analyze_And_Resolve (E, Standard_Float);
11733 end Check_Delta_Expression;
11735 -----------------------------
11736 -- Check_Digits_Expression --
11737 -----------------------------
11739 procedure Check_Digits_Expression (E : Node_Id) is
11741 if not (Is_Integer_Type (Etype (E))) then
11742 Wrong_Type (E, Any_Integer);
11744 elsif not Is_OK_Static_Expression (E) then
11745 Flag_Non_Static_Expr
11746 ("non-static expression used for digits value!", E);
11748 elsif Expr_Value (E) <= 0 then
11749 Error_Msg_N ("digits value must be greater than zero", E);
11755 -- If any of above errors occurred, then replace the incorrect
11756 -- expression by the integer 1, which should prevent further errors.
11758 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11759 Analyze_And_Resolve (E, Standard_Integer);
11761 end Check_Digits_Expression;
11763 --------------------------
11764 -- Check_Initialization --
11765 --------------------------
11767 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11769 -- Special processing for limited types
11771 if Is_Limited_Type (T)
11772 and then not In_Instance
11773 and then not In_Inlined_Body
11775 if not OK_For_Limited_Init (T, Exp) then
11777 -- In GNAT mode, this is just a warning, to allow it to be evilly
11778 -- turned off. Otherwise it is a real error.
11782 ("??cannot initialize entities of limited type!", Exp);
11784 elsif Ada_Version < Ada_2005 then
11786 -- The side effect removal machinery may generate illegal Ada
11787 -- code to avoid the usage of access types and 'reference in
11788 -- SPARK mode. Since this is legal code with respect to theorem
11789 -- proving, do not emit the error.
11792 and then Nkind (Exp) = N_Function_Call
11793 and then Nkind (Parent (Exp)) = N_Object_Declaration
11794 and then not Comes_From_Source
11795 (Defining_Identifier (Parent (Exp)))
11801 ("cannot initialize entities of limited type", Exp);
11802 Explain_Limited_Type (T, Exp);
11806 -- Specialize error message according to kind of illegal
11807 -- initial expression.
11809 if Nkind (Exp) = N_Type_Conversion
11810 and then Nkind (Expression (Exp)) = N_Function_Call
11812 -- No error for internally-generated object declarations,
11813 -- which can come from build-in-place assignment statements.
11815 if Nkind (Parent (Exp)) = N_Object_Declaration
11816 and then not Comes_From_Source
11817 (Defining_Identifier (Parent (Exp)))
11823 ("illegal context for call"
11824 & " to function with limited result", Exp);
11829 ("initialization of limited object requires aggregate "
11830 & "or function call", Exp);
11836 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11837 -- set unless we can be sure that no range check is required.
11839 if (GNATprove_Mode or not Expander_Active)
11840 and then Is_Scalar_Type (T)
11841 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11843 Set_Do_Range_Check (Exp);
11845 end Check_Initialization;
11847 ----------------------
11848 -- Check_Interfaces --
11849 ----------------------
11851 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11852 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11855 Iface_Def : Node_Id;
11856 Iface_Typ : Entity_Id;
11857 Parent_Node : Node_Id;
11859 Is_Task : Boolean := False;
11860 -- Set True if parent type or any progenitor is a task interface
11862 Is_Protected : Boolean := False;
11863 -- Set True if parent type or any progenitor is a protected interface
11865 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11866 -- Check that a progenitor is compatible with declaration. If an error
11867 -- message is output, it is posted on Error_Node.
11873 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11874 Iface_Id : constant Entity_Id :=
11875 Defining_Identifier (Parent (Iface_Def));
11876 Type_Def : Node_Id;
11879 if Nkind (N) = N_Private_Extension_Declaration then
11882 Type_Def := Type_Definition (N);
11885 if Is_Task_Interface (Iface_Id) then
11888 elsif Is_Protected_Interface (Iface_Id) then
11889 Is_Protected := True;
11892 if Is_Synchronized_Interface (Iface_Id) then
11894 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11895 -- extension derived from a synchronized interface must explicitly
11896 -- be declared synchronized, because the full view will be a
11897 -- synchronized type.
11899 if Nkind (N) = N_Private_Extension_Declaration then
11900 if not Synchronized_Present (N) then
11902 ("private extension of& must be explicitly synchronized",
11906 -- However, by 3.9.4(16/2), a full type that is a record extension
11907 -- is never allowed to derive from a synchronized interface (note
11908 -- that interfaces must be excluded from this check, because those
11909 -- are represented by derived type definitions in some cases).
11911 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11912 and then not Interface_Present (Type_Definition (N))
11914 Error_Msg_N ("record extension cannot derive from synchronized "
11915 & "interface", Error_Node);
11919 -- Check that the characteristics of the progenitor are compatible
11920 -- with the explicit qualifier in the declaration.
11921 -- The check only applies to qualifiers that come from source.
11922 -- Limited_Present also appears in the declaration of corresponding
11923 -- records, and the check does not apply to them.
11925 if Limited_Present (Type_Def)
11927 Is_Concurrent_Record_Type (Defining_Identifier (N))
11929 if Is_Limited_Interface (Parent_Type)
11930 and then not Is_Limited_Interface (Iface_Id)
11933 ("progenitor & must be limited interface",
11934 Error_Node, Iface_Id);
11937 (Task_Present (Iface_Def)
11938 or else Protected_Present (Iface_Def)
11939 or else Synchronized_Present (Iface_Def))
11940 and then Nkind (N) /= N_Private_Extension_Declaration
11941 and then not Error_Posted (N)
11944 ("progenitor & must be limited interface",
11945 Error_Node, Iface_Id);
11948 -- Protected interfaces can only inherit from limited, synchronized
11949 -- or protected interfaces.
11951 elsif Nkind (N) = N_Full_Type_Declaration
11952 and then Protected_Present (Type_Def)
11954 if Limited_Present (Iface_Def)
11955 or else Synchronized_Present (Iface_Def)
11956 or else Protected_Present (Iface_Def)
11960 elsif Task_Present (Iface_Def) then
11961 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11962 & "from task interface", Error_Node);
11965 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11966 & "from non-limited interface", Error_Node);
11969 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11970 -- limited and synchronized.
11972 elsif Synchronized_Present (Type_Def) then
11973 if Limited_Present (Iface_Def)
11974 or else Synchronized_Present (Iface_Def)
11978 elsif Protected_Present (Iface_Def)
11979 and then Nkind (N) /= N_Private_Extension_Declaration
11981 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11982 & "from protected interface", Error_Node);
11984 elsif Task_Present (Iface_Def)
11985 and then Nkind (N) /= N_Private_Extension_Declaration
11987 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11988 & "from task interface", Error_Node);
11990 elsif not Is_Limited_Interface (Iface_Id) then
11991 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11992 & "from non-limited interface", Error_Node);
11995 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11996 -- synchronized or task interfaces.
11998 elsif Nkind (N) = N_Full_Type_Declaration
11999 and then Task_Present (Type_Def)
12001 if Limited_Present (Iface_Def)
12002 or else Synchronized_Present (Iface_Def)
12003 or else Task_Present (Iface_Def)
12007 elsif Protected_Present (Iface_Def) then
12008 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
12009 & "protected interface", Error_Node);
12012 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
12013 & "non-limited interface", Error_Node);
12018 -- Start of processing for Check_Interfaces
12021 if Is_Interface (Parent_Type) then
12022 if Is_Task_Interface (Parent_Type) then
12025 elsif Is_Protected_Interface (Parent_Type) then
12026 Is_Protected := True;
12030 if Nkind (N) = N_Private_Extension_Declaration then
12032 -- Check that progenitors are compatible with declaration
12034 Iface := First (Interface_List (Def));
12035 while Present (Iface) loop
12036 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
12038 Parent_Node := Parent (Base_Type (Iface_Typ));
12039 Iface_Def := Type_Definition (Parent_Node);
12041 if not Is_Interface (Iface_Typ) then
12042 Diagnose_Interface (Iface, Iface_Typ);
12044 Check_Ifaces (Iface_Def, Iface);
12050 if Is_Task and Is_Protected then
12052 ("type cannot derive from task and protected interface", N);
12058 -- Full type declaration of derived type.
12059 -- Check compatibility with parent if it is interface type
12061 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
12062 and then Is_Interface (Parent_Type)
12064 Parent_Node := Parent (Parent_Type);
12066 -- More detailed checks for interface varieties
12069 (Iface_Def => Type_Definition (Parent_Node),
12070 Error_Node => Subtype_Indication (Type_Definition (N)));
12073 Iface := First (Interface_List (Def));
12074 while Present (Iface) loop
12075 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
12077 Parent_Node := Parent (Base_Type (Iface_Typ));
12078 Iface_Def := Type_Definition (Parent_Node);
12080 if not Is_Interface (Iface_Typ) then
12081 Diagnose_Interface (Iface, Iface_Typ);
12084 -- "The declaration of a specific descendant of an interface
12085 -- type freezes the interface type" RM 13.14
12087 Freeze_Before (N, Iface_Typ);
12088 Check_Ifaces (Iface_Def, Error_Node => Iface);
12094 if Is_Task and Is_Protected then
12096 ("type cannot derive from task and protected interface", N);
12098 end Check_Interfaces;
12100 ------------------------------------
12101 -- Check_Or_Process_Discriminants --
12102 ------------------------------------
12104 -- If an incomplete or private type declaration was already given for the
12105 -- type, the discriminants may have already been processed if they were
12106 -- present on the incomplete declaration. In this case a full conformance
12107 -- check has been performed in Find_Type_Name, and we then recheck here
12108 -- some properties that can't be checked on the partial view alone.
12109 -- Otherwise we call Process_Discriminants.
12111 procedure Check_Or_Process_Discriminants
12114 Prev : Entity_Id := Empty)
12117 if Has_Discriminants (T) then
12119 -- Discriminants are already set on T if they were already present
12120 -- on the partial view. Make them visible to component declarations.
12124 -- Discriminant on T (full view) referencing expr on partial view
12126 Prev_D : Entity_Id;
12127 -- Entity of corresponding discriminant on partial view
12130 -- Discriminant specification for full view, expression is
12131 -- the syntactic copy on full view (which has been checked for
12132 -- conformance with partial view), only used here to post error
12136 D := First_Discriminant (T);
12137 New_D := First (Discriminant_Specifications (N));
12138 while Present (D) loop
12139 Prev_D := Current_Entity (D);
12140 Set_Current_Entity (D);
12141 Set_Is_Immediately_Visible (D);
12142 Set_Homonym (D, Prev_D);
12144 -- Handle the case where there is an untagged partial view and
12145 -- the full view is tagged: must disallow discriminants with
12146 -- defaults, unless compiling for Ada 2012, which allows a
12147 -- limited tagged type to have defaulted discriminants (see
12148 -- AI05-0214). However, suppress error here if it was already
12149 -- reported on the default expression of the partial view.
12151 if Is_Tagged_Type (T)
12152 and then Present (Expression (Parent (D)))
12153 and then (not Is_Limited_Type (Current_Scope)
12154 or else Ada_Version < Ada_2012)
12155 and then not Error_Posted (Expression (Parent (D)))
12157 if Ada_Version >= Ada_2012 then
12159 ("discriminants of nonlimited tagged type cannot have "
12161 Expression (New_D));
12164 ("discriminants of tagged type cannot have defaults",
12165 Expression (New_D));
12169 -- Ada 2005 (AI-230): Access discriminant allowed in
12170 -- non-limited record types.
12172 if Ada_Version < Ada_2005 then
12174 -- This restriction gets applied to the full type here. It
12175 -- has already been applied earlier to the partial view.
12177 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
12180 Next_Discriminant (D);
12185 elsif Present (Discriminant_Specifications (N)) then
12186 Process_Discriminants (N, Prev);
12188 end Check_Or_Process_Discriminants;
12190 ----------------------
12191 -- Check_Real_Bound --
12192 ----------------------
12194 procedure Check_Real_Bound (Bound : Node_Id) is
12196 if not Is_Real_Type (Etype (Bound)) then
12198 ("bound in real type definition must be of real type", Bound);
12200 elsif not Is_OK_Static_Expression (Bound) then
12201 Flag_Non_Static_Expr
12202 ("non-static expression used for real type bound!", Bound);
12209 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
12211 Resolve (Bound, Standard_Float);
12212 end Check_Real_Bound;
12214 ------------------------------
12215 -- Complete_Private_Subtype --
12216 ------------------------------
12218 procedure Complete_Private_Subtype
12221 Full_Base : Entity_Id;
12222 Related_Nod : Node_Id)
12224 Save_Next_Entity : Entity_Id;
12225 Save_Homonym : Entity_Id;
12228 -- Set semantic attributes for (implicit) private subtype completion.
12229 -- If the full type has no discriminants, then it is a copy of the
12230 -- full view of the base. Otherwise, it is a subtype of the base with
12231 -- a possible discriminant constraint. Save and restore the original
12232 -- Next_Entity field of full to ensure that the calls to Copy_Node do
12233 -- not corrupt the entity chain.
12235 -- Note that the type of the full view is the same entity as the type
12236 -- of the partial view. In this fashion, the subtype has access to the
12237 -- correct view of the parent.
12239 Save_Next_Entity := Next_Entity (Full);
12240 Save_Homonym := Homonym (Priv);
12242 case Ekind (Full_Base) is
12243 when Class_Wide_Kind
12250 Copy_Node (Priv, Full);
12252 Set_Has_Discriminants
12253 (Full, Has_Discriminants (Full_Base));
12254 Set_Has_Unknown_Discriminants
12255 (Full, Has_Unknown_Discriminants (Full_Base));
12256 Set_First_Entity (Full, First_Entity (Full_Base));
12257 Set_Last_Entity (Full, Last_Entity (Full_Base));
12259 -- If the underlying base type is constrained, we know that the
12260 -- full view of the subtype is constrained as well (the converse
12261 -- is not necessarily true).
12263 if Is_Constrained (Full_Base) then
12264 Set_Is_Constrained (Full);
12268 Copy_Node (Full_Base, Full);
12270 Set_Chars (Full, Chars (Priv));
12271 Conditional_Delay (Full, Priv);
12272 Set_Sloc (Full, Sloc (Priv));
12275 Set_Next_Entity (Full, Save_Next_Entity);
12276 Set_Homonym (Full, Save_Homonym);
12277 Set_Associated_Node_For_Itype (Full, Related_Nod);
12279 -- Set common attributes for all subtypes: kind, convention, etc.
12281 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
12282 Set_Convention (Full, Convention (Full_Base));
12284 -- The Etype of the full view is inconsistent. Gigi needs to see the
12285 -- structural full view, which is what the current scheme gives: the
12286 -- Etype of the full view is the etype of the full base. However, if the
12287 -- full base is a derived type, the full view then looks like a subtype
12288 -- of the parent, not a subtype of the full base. If instead we write:
12290 -- Set_Etype (Full, Full_Base);
12292 -- then we get inconsistencies in the front-end (confusion between
12293 -- views). Several outstanding bugs are related to this ???
12295 Set_Is_First_Subtype (Full, False);
12296 Set_Scope (Full, Scope (Priv));
12297 Set_Size_Info (Full, Full_Base);
12298 Set_RM_Size (Full, RM_Size (Full_Base));
12299 Set_Is_Itype (Full);
12301 -- A subtype of a private-type-without-discriminants, whose full-view
12302 -- has discriminants with default expressions, is not constrained.
12304 if not Has_Discriminants (Priv) then
12305 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
12307 if Has_Discriminants (Full_Base) then
12308 Set_Discriminant_Constraint
12309 (Full, Discriminant_Constraint (Full_Base));
12311 -- The partial view may have been indefinite, the full view
12314 Set_Has_Unknown_Discriminants
12315 (Full, Has_Unknown_Discriminants (Full_Base));
12319 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
12320 Set_Depends_On_Private (Full, Has_Private_Component (Full));
12322 -- Freeze the private subtype entity if its parent is delayed, and not
12323 -- already frozen. We skip this processing if the type is an anonymous
12324 -- subtype of a record component, or is the corresponding record of a
12325 -- protected type, since these are processed when the enclosing type
12326 -- is frozen. If the parent type is declared in a nested package then
12327 -- the freezing of the private and full views also happens later.
12329 if not Is_Type (Scope (Full)) then
12331 and then In_Same_Source_Unit (Full, Full_Base)
12332 and then Scope (Full_Base) /= Scope (Full)
12334 Set_Has_Delayed_Freeze (Full);
12335 Set_Has_Delayed_Freeze (Priv);
12338 Set_Has_Delayed_Freeze (Full,
12339 Has_Delayed_Freeze (Full_Base)
12340 and then not Is_Frozen (Full_Base));
12344 Set_Freeze_Node (Full, Empty);
12345 Set_Is_Frozen (Full, False);
12346 Set_Full_View (Priv, Full);
12348 if Has_Discriminants (Full) then
12349 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
12350 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
12352 if Has_Unknown_Discriminants (Full) then
12353 Set_Discriminant_Constraint (Full, No_Elist);
12357 if Ekind (Full_Base) = E_Record_Type
12358 and then Has_Discriminants (Full_Base)
12359 and then Has_Discriminants (Priv) -- might not, if errors
12360 and then not Has_Unknown_Discriminants (Priv)
12361 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
12363 Create_Constrained_Components
12364 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
12366 -- If the full base is itself derived from private, build a congruent
12367 -- subtype of its underlying type, for use by the back end. For a
12368 -- constrained record component, the declaration cannot be placed on
12369 -- the component list, but it must nevertheless be built an analyzed, to
12370 -- supply enough information for Gigi to compute the size of component.
12372 elsif Ekind (Full_Base) in Private_Kind
12373 and then Is_Derived_Type (Full_Base)
12374 and then Has_Discriminants (Full_Base)
12375 and then (Ekind (Current_Scope) /= E_Record_Subtype)
12377 if not Is_Itype (Priv)
12379 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
12381 Build_Underlying_Full_View
12382 (Parent (Priv), Full, Etype (Full_Base));
12384 elsif Nkind (Related_Nod) = N_Component_Declaration then
12385 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
12388 elsif Is_Record_Type (Full_Base) then
12390 -- Show Full is simply a renaming of Full_Base
12392 Set_Cloned_Subtype (Full, Full_Base);
12395 -- It is unsafe to share the bounds of a scalar type, because the Itype
12396 -- is elaborated on demand, and if a bound is non-static then different
12397 -- orders of elaboration in different units will lead to different
12398 -- external symbols.
12400 if Is_Scalar_Type (Full_Base) then
12401 Set_Scalar_Range (Full,
12402 Make_Range (Sloc (Related_Nod),
12404 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
12406 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
12408 -- This completion inherits the bounds of the full parent, but if
12409 -- the parent is an unconstrained floating point type, so is the
12412 if Is_Floating_Point_Type (Full_Base) then
12413 Set_Includes_Infinities
12414 (Scalar_Range (Full), Has_Infinities (Full_Base));
12418 -- ??? It seems that a lot of fields are missing that should be copied
12419 -- from Full_Base to Full. Here are some that are introduced in a
12420 -- non-disruptive way but a cleanup is necessary.
12422 if Is_Tagged_Type (Full_Base) then
12423 Set_Is_Tagged_Type (Full);
12424 Set_Direct_Primitive_Operations
12425 (Full, Direct_Primitive_Operations (Full_Base));
12426 Set_No_Tagged_Streams_Pragma
12427 (Full, No_Tagged_Streams_Pragma (Full_Base));
12429 -- Inherit class_wide type of full_base in case the partial view was
12430 -- not tagged. Otherwise it has already been created when the private
12431 -- subtype was analyzed.
12433 if No (Class_Wide_Type (Full)) then
12434 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
12437 -- If this is a subtype of a protected or task type, constrain its
12438 -- corresponding record, unless this is a subtype without constraints,
12439 -- i.e. a simple renaming as with an actual subtype in an instance.
12441 elsif Is_Concurrent_Type (Full_Base) then
12442 if Has_Discriminants (Full)
12443 and then Present (Corresponding_Record_Type (Full_Base))
12445 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
12447 Set_Corresponding_Record_Type (Full,
12448 Constrain_Corresponding_Record
12449 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
12452 Set_Corresponding_Record_Type (Full,
12453 Corresponding_Record_Type (Full_Base));
12457 -- Link rep item chain, and also setting of Has_Predicates from private
12458 -- subtype to full subtype, since we will need these on the full subtype
12459 -- to create the predicate function. Note that the full subtype may
12460 -- already have rep items, inherited from the full view of the base
12461 -- type, so we must be sure not to overwrite these entries.
12466 Next_Item : Node_Id;
12467 Priv_Item : Node_Id;
12470 Item := First_Rep_Item (Full);
12471 Priv_Item := First_Rep_Item (Priv);
12473 -- If no existing rep items on full type, we can just link directly
12474 -- to the list of items on the private type, if any exist.. Same if
12475 -- the rep items are only those inherited from the base
12478 or else Nkind (Item) /= N_Aspect_Specification
12479 or else Entity (Item) = Full_Base)
12480 and then Present (First_Rep_Item (Priv))
12482 Set_First_Rep_Item (Full, Priv_Item);
12484 -- Otherwise, search to the end of items currently linked to the full
12485 -- subtype and append the private items to the end. However, if Priv
12486 -- and Full already have the same list of rep items, then the append
12487 -- is not done, as that would create a circularity.
12489 -- The partial view may have a predicate and the rep item lists of
12490 -- both views agree when inherited from the same ancestor. In that
12491 -- case, simply propagate the list from one view to the other.
12492 -- A more complex analysis needed here ???
12494 elsif Present (Priv_Item)
12495 and then Item = Next_Rep_Item (Priv_Item)
12497 Set_First_Rep_Item (Full, Priv_Item);
12499 elsif Item /= Priv_Item then
12502 Next_Item := Next_Rep_Item (Item);
12503 exit when No (Next_Item);
12506 -- If the private view has aspect specifications, the full view
12507 -- inherits them. Since these aspects may already have been
12508 -- attached to the full view during derivation, do not append
12509 -- them if already present.
12511 if Item = First_Rep_Item (Priv) then
12517 -- And link the private type items at the end of the chain
12520 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
12525 -- Make sure Has_Predicates is set on full type if it is set on the
12526 -- private type. Note that it may already be set on the full type and
12527 -- if so, we don't want to unset it. Similarly, propagate information
12528 -- about delayed aspects, because the corresponding pragmas must be
12529 -- analyzed when one of the views is frozen. This last step is needed
12530 -- in particular when the full type is a scalar type for which an
12531 -- anonymous base type is constructed.
12533 -- The predicate functions are generated either at the freeze point
12534 -- of the type or at the end of the visible part, and we must avoid
12535 -- generating them twice.
12537 if Has_Predicates (Priv) then
12538 Set_Has_Predicates (Full);
12540 if Present (Predicate_Function (Priv))
12541 and then No (Predicate_Function (Full))
12543 Set_Predicate_Function (Full, Predicate_Function (Priv));
12547 if Has_Delayed_Aspects (Priv) then
12548 Set_Has_Delayed_Aspects (Full);
12550 end Complete_Private_Subtype;
12552 ----------------------------
12553 -- Constant_Redeclaration --
12554 ----------------------------
12556 procedure Constant_Redeclaration
12561 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
12562 Obj_Def : constant Node_Id := Object_Definition (N);
12565 procedure Check_Possible_Deferred_Completion
12566 (Prev_Id : Entity_Id;
12567 Prev_Obj_Def : Node_Id;
12568 Curr_Obj_Def : Node_Id);
12569 -- Determine whether the two object definitions describe the partial
12570 -- and the full view of a constrained deferred constant. Generate
12571 -- a subtype for the full view and verify that it statically matches
12572 -- the subtype of the partial view.
12574 procedure Check_Recursive_Declaration (Typ : Entity_Id);
12575 -- If deferred constant is an access type initialized with an allocator,
12576 -- check whether there is an illegal recursion in the definition,
12577 -- through a default value of some record subcomponent. This is normally
12578 -- detected when generating init procs, but requires this additional
12579 -- mechanism when expansion is disabled.
12581 ----------------------------------------
12582 -- Check_Possible_Deferred_Completion --
12583 ----------------------------------------
12585 procedure Check_Possible_Deferred_Completion
12586 (Prev_Id : Entity_Id;
12587 Prev_Obj_Def : Node_Id;
12588 Curr_Obj_Def : Node_Id)
12591 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
12592 and then Present (Constraint (Prev_Obj_Def))
12593 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
12594 and then Present (Constraint (Curr_Obj_Def))
12597 Loc : constant Source_Ptr := Sloc (N);
12598 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
12599 Decl : constant Node_Id :=
12600 Make_Subtype_Declaration (Loc,
12601 Defining_Identifier => Def_Id,
12602 Subtype_Indication =>
12603 Relocate_Node (Curr_Obj_Def));
12606 Insert_Before_And_Analyze (N, Decl);
12607 Set_Etype (Id, Def_Id);
12609 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
12610 Error_Msg_Sloc := Sloc (Prev_Id);
12611 Error_Msg_N ("subtype does not statically match deferred "
12612 & "declaration #", N);
12616 end Check_Possible_Deferred_Completion;
12618 ---------------------------------
12619 -- Check_Recursive_Declaration --
12620 ---------------------------------
12622 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
12626 if Is_Record_Type (Typ) then
12627 Comp := First_Component (Typ);
12628 while Present (Comp) loop
12629 if Comes_From_Source (Comp) then
12630 if Present (Expression (Parent (Comp)))
12631 and then Is_Entity_Name (Expression (Parent (Comp)))
12632 and then Entity (Expression (Parent (Comp))) = Prev
12634 Error_Msg_Sloc := Sloc (Parent (Comp));
12636 ("illegal circularity with declaration for & #",
12640 elsif Is_Record_Type (Etype (Comp)) then
12641 Check_Recursive_Declaration (Etype (Comp));
12645 Next_Component (Comp);
12648 end Check_Recursive_Declaration;
12650 -- Start of processing for Constant_Redeclaration
12653 if Nkind (Parent (Prev)) = N_Object_Declaration then
12654 if Nkind (Object_Definition
12655 (Parent (Prev))) = N_Subtype_Indication
12657 -- Find type of new declaration. The constraints of the two
12658 -- views must match statically, but there is no point in
12659 -- creating an itype for the full view.
12661 if Nkind (Obj_Def) = N_Subtype_Indication then
12662 Find_Type (Subtype_Mark (Obj_Def));
12663 New_T := Entity (Subtype_Mark (Obj_Def));
12666 Find_Type (Obj_Def);
12667 New_T := Entity (Obj_Def);
12673 -- The full view may impose a constraint, even if the partial
12674 -- view does not, so construct the subtype.
12676 New_T := Find_Type_Of_Object (Obj_Def, N);
12681 -- Current declaration is illegal, diagnosed below in Enter_Name
12687 -- If previous full declaration or a renaming declaration exists, or if
12688 -- a homograph is present, let Enter_Name handle it, either with an
12689 -- error or with the removal of an overridden implicit subprogram.
12690 -- The previous one is a full declaration if it has an expression
12691 -- (which in the case of an aggregate is indicated by the Init flag).
12693 if Ekind (Prev) /= E_Constant
12694 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12695 or else Present (Expression (Parent (Prev)))
12696 or else Has_Init_Expression (Parent (Prev))
12697 or else Present (Full_View (Prev))
12701 -- Verify that types of both declarations match, or else that both types
12702 -- are anonymous access types whose designated subtypes statically match
12703 -- (as allowed in Ada 2005 by AI-385).
12705 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12707 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12708 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12709 or else Is_Access_Constant (Etype (New_T)) /=
12710 Is_Access_Constant (Etype (Prev))
12711 or else Can_Never_Be_Null (Etype (New_T)) /=
12712 Can_Never_Be_Null (Etype (Prev))
12713 or else Null_Exclusion_Present (Parent (Prev)) /=
12714 Null_Exclusion_Present (Parent (Id))
12715 or else not Subtypes_Statically_Match
12716 (Designated_Type (Etype (Prev)),
12717 Designated_Type (Etype (New_T))))
12719 Error_Msg_Sloc := Sloc (Prev);
12720 Error_Msg_N ("type does not match declaration#", N);
12721 Set_Full_View (Prev, Id);
12722 Set_Etype (Id, Any_Type);
12724 -- A deferred constant whose type is an anonymous array is always
12725 -- illegal (unless imported). A detailed error message might be
12726 -- helpful for Ada beginners.
12728 if Nkind (Object_Definition (Parent (Prev)))
12729 = N_Constrained_Array_Definition
12730 and then Nkind (Object_Definition (N))
12731 = N_Constrained_Array_Definition
12733 Error_Msg_N ("\each anonymous array is a distinct type", N);
12734 Error_Msg_N ("a deferred constant must have a named type",
12735 Object_Definition (Parent (Prev)));
12739 Null_Exclusion_Present (Parent (Prev))
12740 and then not Null_Exclusion_Present (N)
12742 Error_Msg_Sloc := Sloc (Prev);
12743 Error_Msg_N ("null-exclusion does not match declaration#", N);
12744 Set_Full_View (Prev, Id);
12745 Set_Etype (Id, Any_Type);
12747 -- If so, process the full constant declaration
12750 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12751 -- the deferred declaration is constrained, then the subtype defined
12752 -- by the subtype_indication in the full declaration shall match it
12755 Check_Possible_Deferred_Completion
12757 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12758 Curr_Obj_Def => Obj_Def);
12760 Set_Full_View (Prev, Id);
12761 Set_Is_Public (Id, Is_Public (Prev));
12762 Set_Is_Internal (Id);
12763 Append_Entity (Id, Current_Scope);
12765 -- Check ALIASED present if present before (RM 7.4(7))
12767 if Is_Aliased (Prev)
12768 and then not Aliased_Present (N)
12770 Error_Msg_Sloc := Sloc (Prev);
12771 Error_Msg_N ("ALIASED required (see declaration #)", N);
12774 -- Check that placement is in private part and that the incomplete
12775 -- declaration appeared in the visible part.
12777 if Ekind (Current_Scope) = E_Package
12778 and then not In_Private_Part (Current_Scope)
12780 Error_Msg_Sloc := Sloc (Prev);
12782 ("full constant for declaration # must be in private part", N);
12784 elsif Ekind (Current_Scope) = E_Package
12786 List_Containing (Parent (Prev)) /=
12787 Visible_Declarations (Package_Specification (Current_Scope))
12790 ("deferred constant must be declared in visible part",
12794 if Is_Access_Type (T)
12795 and then Nkind (Expression (N)) = N_Allocator
12797 Check_Recursive_Declaration (Designated_Type (T));
12800 -- A deferred constant is a visible entity. If type has invariants,
12801 -- verify that the initial value satisfies them. This is not done in
12802 -- GNATprove mode, as GNATprove handles invariant checks itself.
12804 if Has_Invariants (T)
12805 and then Present (Invariant_Procedure (T))
12806 and then not GNATprove_Mode
12809 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12812 end Constant_Redeclaration;
12814 ----------------------
12815 -- Constrain_Access --
12816 ----------------------
12818 procedure Constrain_Access
12819 (Def_Id : in out Entity_Id;
12821 Related_Nod : Node_Id)
12823 T : constant Entity_Id := Entity (Subtype_Mark (S));
12824 Desig_Type : constant Entity_Id := Designated_Type (T);
12825 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12826 Constraint_OK : Boolean := True;
12829 if Is_Array_Type (Desig_Type) then
12830 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12832 elsif (Is_Record_Type (Desig_Type)
12833 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12834 and then not Is_Constrained (Desig_Type)
12836 -- ??? The following code is a temporary bypass to ignore a
12837 -- discriminant constraint on access type if it is constraining
12838 -- the current record. Avoid creating the implicit subtype of the
12839 -- record we are currently compiling since right now, we cannot
12840 -- handle these. For now, just return the access type itself.
12842 if Desig_Type = Current_Scope
12843 and then No (Def_Id)
12845 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12846 Def_Id := Entity (Subtype_Mark (S));
12848 -- This call added to ensure that the constraint is analyzed
12849 -- (needed for a B test). Note that we still return early from
12850 -- this procedure to avoid recursive processing. ???
12852 Constrain_Discriminated_Type
12853 (Desig_Subtype, S, Related_Nod, For_Access => True);
12857 -- Enforce rule that the constraint is illegal if there is an
12858 -- unconstrained view of the designated type. This means that the
12859 -- partial view (either a private type declaration or a derivation
12860 -- from a private type) has no discriminants. (Defect Report
12861 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12863 -- Rule updated for Ada 2005: The private type is said to have
12864 -- a constrained partial view, given that objects of the type
12865 -- can be declared. Furthermore, the rule applies to all access
12866 -- types, unlike the rule concerning default discriminants (see
12869 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12870 and then Has_Private_Declaration (Desig_Type)
12871 and then In_Open_Scopes (Scope (Desig_Type))
12872 and then Has_Discriminants (Desig_Type)
12875 Pack : constant Node_Id :=
12876 Unit_Declaration_Node (Scope (Desig_Type));
12881 if Nkind (Pack) = N_Package_Declaration then
12882 Decls := Visible_Declarations (Specification (Pack));
12883 Decl := First (Decls);
12884 while Present (Decl) loop
12885 if (Nkind (Decl) = N_Private_Type_Declaration
12886 and then Chars (Defining_Identifier (Decl)) =
12887 Chars (Desig_Type))
12890 (Nkind (Decl) = N_Full_Type_Declaration
12892 Chars (Defining_Identifier (Decl)) =
12894 and then Is_Derived_Type (Desig_Type)
12896 Has_Private_Declaration (Etype (Desig_Type)))
12898 if No (Discriminant_Specifications (Decl)) then
12900 ("cannot constrain access type if designated "
12901 & "type has constrained partial view", S);
12913 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12914 For_Access => True);
12916 elsif Is_Concurrent_Type (Desig_Type)
12917 and then not Is_Constrained (Desig_Type)
12919 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12922 Error_Msg_N ("invalid constraint on access type", S);
12924 -- We simply ignore an invalid constraint
12926 Desig_Subtype := Desig_Type;
12927 Constraint_OK := False;
12930 if No (Def_Id) then
12931 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12933 Set_Ekind (Def_Id, E_Access_Subtype);
12936 if Constraint_OK then
12937 Set_Etype (Def_Id, Base_Type (T));
12939 if Is_Private_Type (Desig_Type) then
12940 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12943 Set_Etype (Def_Id, Any_Type);
12946 Set_Size_Info (Def_Id, T);
12947 Set_Is_Constrained (Def_Id, Constraint_OK);
12948 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12949 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12950 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12952 Conditional_Delay (Def_Id, T);
12954 -- AI-363 : Subtypes of general access types whose designated types have
12955 -- default discriminants are disallowed. In instances, the rule has to
12956 -- be checked against the actual, of which T is the subtype. In a
12957 -- generic body, the rule is checked assuming that the actual type has
12958 -- defaulted discriminants.
12960 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12961 if Ekind (Base_Type (T)) = E_General_Access_Type
12962 and then Has_Defaulted_Discriminants (Desig_Type)
12964 if Ada_Version < Ada_2005 then
12966 ("access subtype of general access type would not " &
12967 "be allowed in Ada 2005?y?", S);
12970 ("access subtype of general access type not allowed", S);
12973 Error_Msg_N ("\discriminants have defaults", S);
12975 elsif Is_Access_Type (T)
12976 and then Is_Generic_Type (Desig_Type)
12977 and then Has_Discriminants (Desig_Type)
12978 and then In_Package_Body (Current_Scope)
12980 if Ada_Version < Ada_2005 then
12982 ("access subtype would not be allowed in generic body "
12983 & "in Ada 2005?y?", S);
12986 ("access subtype not allowed in generic body", S);
12990 ("\designated type is a discriminated formal", S);
12993 end Constrain_Access;
12995 ---------------------
12996 -- Constrain_Array --
12997 ---------------------
12999 procedure Constrain_Array
13000 (Def_Id : in out Entity_Id;
13002 Related_Nod : Node_Id;
13003 Related_Id : Entity_Id;
13004 Suffix : Character)
13006 C : constant Node_Id := Constraint (SI);
13007 Number_Of_Constraints : Nat := 0;
13010 Constraint_OK : Boolean := True;
13013 T := Entity (Subtype_Mark (SI));
13015 if Is_Access_Type (T) then
13016 T := Designated_Type (T);
13019 -- If an index constraint follows a subtype mark in a subtype indication
13020 -- then the type or subtype denoted by the subtype mark must not already
13021 -- impose an index constraint. The subtype mark must denote either an
13022 -- unconstrained array type or an access type whose designated type
13023 -- is such an array type... (RM 3.6.1)
13025 if Is_Constrained (T) then
13026 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
13027 Constraint_OK := False;
13030 S := First (Constraints (C));
13031 while Present (S) loop
13032 Number_Of_Constraints := Number_Of_Constraints + 1;
13036 -- In either case, the index constraint must provide a discrete
13037 -- range for each index of the array type and the type of each
13038 -- discrete range must be the same as that of the corresponding
13039 -- index. (RM 3.6.1)
13041 if Number_Of_Constraints /= Number_Dimensions (T) then
13042 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
13043 Constraint_OK := False;
13046 S := First (Constraints (C));
13047 Index := First_Index (T);
13050 -- Apply constraints to each index type
13052 for J in 1 .. Number_Of_Constraints loop
13053 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
13061 if No (Def_Id) then
13063 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
13064 Set_Parent (Def_Id, Related_Nod);
13067 Set_Ekind (Def_Id, E_Array_Subtype);
13070 Set_Size_Info (Def_Id, (T));
13071 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13072 Set_Etype (Def_Id, Base_Type (T));
13074 if Constraint_OK then
13075 Set_First_Index (Def_Id, First (Constraints (C)));
13077 Set_First_Index (Def_Id, First_Index (T));
13080 Set_Is_Constrained (Def_Id, True);
13081 Set_Is_Aliased (Def_Id, Is_Aliased (T));
13082 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
13084 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
13085 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
13087 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
13088 -- We need to initialize the attribute because if Def_Id is previously
13089 -- analyzed through a limited_with clause, it will have the attributes
13090 -- of an incomplete type, one of which is an Elist that overlaps the
13091 -- Packed_Array_Impl_Type field.
13093 Set_Packed_Array_Impl_Type (Def_Id, Empty);
13095 -- Build a freeze node if parent still needs one. Also make sure that
13096 -- the Depends_On_Private status is set because the subtype will need
13097 -- reprocessing at the time the base type does, and also we must set a
13098 -- conditional delay.
13100 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
13101 Conditional_Delay (Def_Id, T);
13102 end Constrain_Array;
13104 ------------------------------
13105 -- Constrain_Component_Type --
13106 ------------------------------
13108 function Constrain_Component_Type
13110 Constrained_Typ : Entity_Id;
13111 Related_Node : Node_Id;
13113 Constraints : Elist_Id) return Entity_Id
13115 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
13116 Compon_Type : constant Entity_Id := Etype (Comp);
13118 function Build_Constrained_Array_Type
13119 (Old_Type : Entity_Id) return Entity_Id;
13120 -- If Old_Type is an array type, one of whose indexes is constrained
13121 -- by a discriminant, build an Itype whose constraint replaces the
13122 -- discriminant with its value in the constraint.
13124 function Build_Constrained_Discriminated_Type
13125 (Old_Type : Entity_Id) return Entity_Id;
13126 -- Ditto for record components
13128 function Build_Constrained_Access_Type
13129 (Old_Type : Entity_Id) return Entity_Id;
13130 -- Ditto for access types. Makes use of previous two functions, to
13131 -- constrain designated type.
13133 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
13134 -- T is an array or discriminated type, C is a list of constraints
13135 -- that apply to T. This routine builds the constrained subtype.
13137 function Is_Discriminant (Expr : Node_Id) return Boolean;
13138 -- Returns True if Expr is a discriminant
13140 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
13141 -- Find the value of discriminant Discrim in Constraint
13143 -----------------------------------
13144 -- Build_Constrained_Access_Type --
13145 -----------------------------------
13147 function Build_Constrained_Access_Type
13148 (Old_Type : Entity_Id) return Entity_Id
13150 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
13152 Desig_Subtype : Entity_Id;
13156 -- if the original access type was not embedded in the enclosing
13157 -- type definition, there is no need to produce a new access
13158 -- subtype. In fact every access type with an explicit constraint
13159 -- generates an itype whose scope is the enclosing record.
13161 if not Is_Type (Scope (Old_Type)) then
13164 elsif Is_Array_Type (Desig_Type) then
13165 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
13167 elsif Has_Discriminants (Desig_Type) then
13169 -- This may be an access type to an enclosing record type for
13170 -- which we are constructing the constrained components. Return
13171 -- the enclosing record subtype. This is not always correct,
13172 -- but avoids infinite recursion. ???
13174 Desig_Subtype := Any_Type;
13176 for J in reverse 0 .. Scope_Stack.Last loop
13177 Scop := Scope_Stack.Table (J).Entity;
13180 and then Base_Type (Scop) = Base_Type (Desig_Type)
13182 Desig_Subtype := Scop;
13185 exit when not Is_Type (Scop);
13188 if Desig_Subtype = Any_Type then
13190 Build_Constrained_Discriminated_Type (Desig_Type);
13197 if Desig_Subtype /= Desig_Type then
13199 -- The Related_Node better be here or else we won't be able
13200 -- to attach new itypes to a node in the tree.
13202 pragma Assert (Present (Related_Node));
13204 Itype := Create_Itype (E_Access_Subtype, Related_Node);
13206 Set_Etype (Itype, Base_Type (Old_Type));
13207 Set_Size_Info (Itype, (Old_Type));
13208 Set_Directly_Designated_Type (Itype, Desig_Subtype);
13209 Set_Depends_On_Private (Itype, Has_Private_Component
13211 Set_Is_Access_Constant (Itype, Is_Access_Constant
13214 -- The new itype needs freezing when it depends on a not frozen
13215 -- type and the enclosing subtype needs freezing.
13217 if Has_Delayed_Freeze (Constrained_Typ)
13218 and then not Is_Frozen (Constrained_Typ)
13220 Conditional_Delay (Itype, Base_Type (Old_Type));
13228 end Build_Constrained_Access_Type;
13230 ----------------------------------
13231 -- Build_Constrained_Array_Type --
13232 ----------------------------------
13234 function Build_Constrained_Array_Type
13235 (Old_Type : Entity_Id) return Entity_Id
13239 Old_Index : Node_Id;
13240 Range_Node : Node_Id;
13241 Constr_List : List_Id;
13243 Need_To_Create_Itype : Boolean := False;
13246 Old_Index := First_Index (Old_Type);
13247 while Present (Old_Index) loop
13248 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
13250 if Is_Discriminant (Lo_Expr)
13252 Is_Discriminant (Hi_Expr)
13254 Need_To_Create_Itype := True;
13257 Next_Index (Old_Index);
13260 if Need_To_Create_Itype then
13261 Constr_List := New_List;
13263 Old_Index := First_Index (Old_Type);
13264 while Present (Old_Index) loop
13265 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
13267 if Is_Discriminant (Lo_Expr) then
13268 Lo_Expr := Get_Discr_Value (Lo_Expr);
13271 if Is_Discriminant (Hi_Expr) then
13272 Hi_Expr := Get_Discr_Value (Hi_Expr);
13277 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
13279 Append (Range_Node, To => Constr_List);
13281 Next_Index (Old_Index);
13284 return Build_Subtype (Old_Type, Constr_List);
13289 end Build_Constrained_Array_Type;
13291 ------------------------------------------
13292 -- Build_Constrained_Discriminated_Type --
13293 ------------------------------------------
13295 function Build_Constrained_Discriminated_Type
13296 (Old_Type : Entity_Id) return Entity_Id
13299 Constr_List : List_Id;
13300 Old_Constraint : Elmt_Id;
13302 Need_To_Create_Itype : Boolean := False;
13305 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
13306 while Present (Old_Constraint) loop
13307 Expr := Node (Old_Constraint);
13309 if Is_Discriminant (Expr) then
13310 Need_To_Create_Itype := True;
13313 Next_Elmt (Old_Constraint);
13316 if Need_To_Create_Itype then
13317 Constr_List := New_List;
13319 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
13320 while Present (Old_Constraint) loop
13321 Expr := Node (Old_Constraint);
13323 if Is_Discriminant (Expr) then
13324 Expr := Get_Discr_Value (Expr);
13327 Append (New_Copy_Tree (Expr), To => Constr_List);
13329 Next_Elmt (Old_Constraint);
13332 return Build_Subtype (Old_Type, Constr_List);
13337 end Build_Constrained_Discriminated_Type;
13339 -------------------
13340 -- Build_Subtype --
13341 -------------------
13343 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
13345 Subtyp_Decl : Node_Id;
13346 Def_Id : Entity_Id;
13347 Btyp : Entity_Id := Base_Type (T);
13350 -- The Related_Node better be here or else we won't be able to
13351 -- attach new itypes to a node in the tree.
13353 pragma Assert (Present (Related_Node));
13355 -- If the view of the component's type is incomplete or private
13356 -- with unknown discriminants, then the constraint must be applied
13357 -- to the full type.
13359 if Has_Unknown_Discriminants (Btyp)
13360 and then Present (Underlying_Type (Btyp))
13362 Btyp := Underlying_Type (Btyp);
13366 Make_Subtype_Indication (Loc,
13367 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
13368 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
13370 Def_Id := Create_Itype (Ekind (T), Related_Node);
13373 Make_Subtype_Declaration (Loc,
13374 Defining_Identifier => Def_Id,
13375 Subtype_Indication => Indic);
13377 Set_Parent (Subtyp_Decl, Parent (Related_Node));
13379 -- Itypes must be analyzed with checks off (see package Itypes)
13381 Analyze (Subtyp_Decl, Suppress => All_Checks);
13386 ---------------------
13387 -- Get_Discr_Value --
13388 ---------------------
13390 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
13395 -- The discriminant may be declared for the type, in which case we
13396 -- find it by iterating over the list of discriminants. If the
13397 -- discriminant is inherited from a parent type, it appears as the
13398 -- corresponding discriminant of the current type. This will be the
13399 -- case when constraining an inherited component whose constraint is
13400 -- given by a discriminant of the parent.
13402 D := First_Discriminant (Typ);
13403 E := First_Elmt (Constraints);
13405 while Present (D) loop
13406 if D = Entity (Discrim)
13407 or else D = CR_Discriminant (Entity (Discrim))
13408 or else Corresponding_Discriminant (D) = Entity (Discrim)
13413 Next_Discriminant (D);
13417 -- The Corresponding_Discriminant mechanism is incomplete, because
13418 -- the correspondence between new and old discriminants is not one
13419 -- to one: one new discriminant can constrain several old ones. In
13420 -- that case, scan sequentially the stored_constraint, the list of
13421 -- discriminants of the parents, and the constraints.
13423 -- Previous code checked for the present of the Stored_Constraint
13424 -- list for the derived type, but did not use it at all. Should it
13425 -- be present when the component is a discriminated task type?
13427 if Is_Derived_Type (Typ)
13428 and then Scope (Entity (Discrim)) = Etype (Typ)
13430 D := First_Discriminant (Etype (Typ));
13431 E := First_Elmt (Constraints);
13432 while Present (D) loop
13433 if D = Entity (Discrim) then
13437 Next_Discriminant (D);
13442 -- Something is wrong if we did not find the value
13444 raise Program_Error;
13445 end Get_Discr_Value;
13447 ---------------------
13448 -- Is_Discriminant --
13449 ---------------------
13451 function Is_Discriminant (Expr : Node_Id) return Boolean is
13452 Discrim_Scope : Entity_Id;
13455 if Denotes_Discriminant (Expr) then
13456 Discrim_Scope := Scope (Entity (Expr));
13458 -- Either we have a reference to one of Typ's discriminants,
13460 pragma Assert (Discrim_Scope = Typ
13462 -- or to the discriminants of the parent type, in the case
13463 -- of a derivation of a tagged type with variants.
13465 or else Discrim_Scope = Etype (Typ)
13466 or else Full_View (Discrim_Scope) = Etype (Typ)
13468 -- or same as above for the case where the discriminants
13469 -- were declared in Typ's private view.
13471 or else (Is_Private_Type (Discrim_Scope)
13472 and then Chars (Discrim_Scope) = Chars (Typ))
13474 -- or else we are deriving from the full view and the
13475 -- discriminant is declared in the private entity.
13477 or else (Is_Private_Type (Typ)
13478 and then Chars (Discrim_Scope) = Chars (Typ))
13480 -- Or we are constrained the corresponding record of a
13481 -- synchronized type that completes a private declaration.
13483 or else (Is_Concurrent_Record_Type (Typ)
13485 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
13487 -- or we have a class-wide type, in which case make sure the
13488 -- discriminant found belongs to the root type.
13490 or else (Is_Class_Wide_Type (Typ)
13491 and then Etype (Typ) = Discrim_Scope));
13496 -- In all other cases we have something wrong
13499 end Is_Discriminant;
13501 -- Start of processing for Constrain_Component_Type
13504 if Nkind (Parent (Comp)) = N_Component_Declaration
13505 and then Comes_From_Source (Parent (Comp))
13506 and then Comes_From_Source
13507 (Subtype_Indication (Component_Definition (Parent (Comp))))
13510 (Subtype_Indication (Component_Definition (Parent (Comp))))
13512 return Compon_Type;
13514 elsif Is_Array_Type (Compon_Type) then
13515 return Build_Constrained_Array_Type (Compon_Type);
13517 elsif Has_Discriminants (Compon_Type) then
13518 return Build_Constrained_Discriminated_Type (Compon_Type);
13520 elsif Is_Access_Type (Compon_Type) then
13521 return Build_Constrained_Access_Type (Compon_Type);
13524 return Compon_Type;
13526 end Constrain_Component_Type;
13528 --------------------------
13529 -- Constrain_Concurrent --
13530 --------------------------
13532 -- For concurrent types, the associated record value type carries the same
13533 -- discriminants, so when we constrain a concurrent type, we must constrain
13534 -- the corresponding record type as well.
13536 procedure Constrain_Concurrent
13537 (Def_Id : in out Entity_Id;
13539 Related_Nod : Node_Id;
13540 Related_Id : Entity_Id;
13541 Suffix : Character)
13543 -- Retrieve Base_Type to ensure getting to the concurrent type in the
13544 -- case of a private subtype (needed when only doing semantic analysis).
13546 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
13550 if Is_Access_Type (T_Ent) then
13551 T_Ent := Designated_Type (T_Ent);
13554 T_Val := Corresponding_Record_Type (T_Ent);
13556 if Present (T_Val) then
13558 if No (Def_Id) then
13559 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13561 -- Elaborate itype now, as it may be used in a subsequent
13562 -- synchronized operation in another scope.
13564 if Nkind (Related_Nod) = N_Full_Type_Declaration then
13565 Build_Itype_Reference (Def_Id, Related_Nod);
13569 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13570 Set_First_Private_Entity (Def_Id, First_Private_Entity (T_Ent));
13572 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
13573 Set_Corresponding_Record_Type (Def_Id,
13574 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
13577 -- If there is no associated record, expansion is disabled and this
13578 -- is a generic context. Create a subtype in any case, so that
13579 -- semantic analysis can proceed.
13581 if No (Def_Id) then
13582 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13585 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13587 end Constrain_Concurrent;
13589 ------------------------------------
13590 -- Constrain_Corresponding_Record --
13591 ------------------------------------
13593 function Constrain_Corresponding_Record
13594 (Prot_Subt : Entity_Id;
13595 Corr_Rec : Entity_Id;
13596 Related_Nod : Node_Id) return Entity_Id
13598 T_Sub : constant Entity_Id :=
13599 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
13602 Set_Etype (T_Sub, Corr_Rec);
13603 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
13604 Set_Is_Constrained (T_Sub, True);
13605 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
13606 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
13608 if Has_Discriminants (Prot_Subt) then -- False only if errors.
13609 Set_Discriminant_Constraint
13610 (T_Sub, Discriminant_Constraint (Prot_Subt));
13611 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
13612 Create_Constrained_Components
13613 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
13616 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
13618 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
13619 Conditional_Delay (T_Sub, Corr_Rec);
13622 -- This is a component subtype: it will be frozen in the context of
13623 -- the enclosing record's init_proc, so that discriminant references
13624 -- are resolved to discriminals. (Note: we used to skip freezing
13625 -- altogether in that case, which caused errors downstream for
13626 -- components of a bit packed array type).
13628 Set_Has_Delayed_Freeze (T_Sub);
13632 end Constrain_Corresponding_Record;
13634 -----------------------
13635 -- Constrain_Decimal --
13636 -----------------------
13638 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
13639 T : constant Entity_Id := Entity (Subtype_Mark (S));
13640 C : constant Node_Id := Constraint (S);
13641 Loc : constant Source_Ptr := Sloc (C);
13642 Range_Expr : Node_Id;
13643 Digits_Expr : Node_Id;
13648 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
13650 if Nkind (C) = N_Range_Constraint then
13651 Range_Expr := Range_Expression (C);
13652 Digits_Val := Digits_Value (T);
13655 pragma Assert (Nkind (C) = N_Digits_Constraint);
13657 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13659 Digits_Expr := Digits_Expression (C);
13660 Analyze_And_Resolve (Digits_Expr, Any_Integer);
13662 Check_Digits_Expression (Digits_Expr);
13663 Digits_Val := Expr_Value (Digits_Expr);
13665 if Digits_Val > Digits_Value (T) then
13667 ("digits expression is incompatible with subtype", C);
13668 Digits_Val := Digits_Value (T);
13671 if Present (Range_Constraint (C)) then
13672 Range_Expr := Range_Expression (Range_Constraint (C));
13674 Range_Expr := Empty;
13678 Set_Etype (Def_Id, Base_Type (T));
13679 Set_Size_Info (Def_Id, (T));
13680 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13681 Set_Delta_Value (Def_Id, Delta_Value (T));
13682 Set_Scale_Value (Def_Id, Scale_Value (T));
13683 Set_Small_Value (Def_Id, Small_Value (T));
13684 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
13685 Set_Digits_Value (Def_Id, Digits_Val);
13687 -- Manufacture range from given digits value if no range present
13689 if No (Range_Expr) then
13690 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
13694 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13696 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13699 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13700 Set_Discrete_RM_Size (Def_Id);
13702 -- Unconditionally delay the freeze, since we cannot set size
13703 -- information in all cases correctly until the freeze point.
13705 Set_Has_Delayed_Freeze (Def_Id);
13706 end Constrain_Decimal;
13708 ----------------------------------
13709 -- Constrain_Discriminated_Type --
13710 ----------------------------------
13712 procedure Constrain_Discriminated_Type
13713 (Def_Id : Entity_Id;
13715 Related_Nod : Node_Id;
13716 For_Access : Boolean := False)
13718 E : Entity_Id := Entity (Subtype_Mark (S));
13721 procedure Fixup_Bad_Constraint;
13722 -- Called after finding a bad constraint, and after having posted an
13723 -- appropriate error message. The goal is to leave type Def_Id in as
13724 -- reasonable state as possible.
13726 --------------------------
13727 -- Fixup_Bad_Constraint --
13728 --------------------------
13730 procedure Fixup_Bad_Constraint is
13732 -- Set a reasonable Ekind for the entity, including incomplete types.
13734 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13736 -- Set Etype to the known type, to reduce chances of cascaded errors
13738 Set_Etype (Def_Id, E);
13739 Set_Error_Posted (Def_Id);
13740 end Fixup_Bad_Constraint;
13745 Constr : Elist_Id := New_Elmt_List;
13747 -- Start of processing for Constrain_Discriminated_Type
13750 C := Constraint (S);
13752 -- A discriminant constraint is only allowed in a subtype indication,
13753 -- after a subtype mark. This subtype mark must denote either a type
13754 -- with discriminants, or an access type whose designated type is a
13755 -- type with discriminants. A discriminant constraint specifies the
13756 -- values of these discriminants (RM 3.7.2(5)).
13758 T := Base_Type (Entity (Subtype_Mark (S)));
13760 if Is_Access_Type (T) then
13761 T := Designated_Type (T);
13764 -- In an instance it may be necessary to retrieve the full view of a
13765 -- type with unknown discriminants, or a full view with defaulted
13766 -- discriminants. In other contexts the constraint is illegal.
13769 and then Is_Private_Type (T)
13770 and then Present (Full_View (T))
13772 (Has_Unknown_Discriminants (T)
13774 (not Has_Discriminants (T)
13775 and then Has_Discriminants (Full_View (T))
13776 and then Present (Discriminant_Default_Value
13777 (First_Discriminant (Full_View (T))))))
13779 T := Full_View (T);
13780 E := Full_View (E);
13783 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal. Avoid
13784 -- generating an error for access-to-incomplete subtypes.
13786 if Ada_Version >= Ada_2005
13787 and then Ekind (T) = E_Incomplete_Type
13788 and then Nkind (Parent (S)) = N_Subtype_Declaration
13789 and then not Is_Itype (Def_Id)
13791 -- A little sanity check: emit an error message if the type has
13792 -- discriminants to begin with. Type T may be a regular incomplete
13793 -- type or imported via a limited with clause.
13795 if Has_Discriminants (T)
13796 or else (From_Limited_With (T)
13797 and then Present (Non_Limited_View (T))
13798 and then Nkind (Parent (Non_Limited_View (T))) =
13799 N_Full_Type_Declaration
13800 and then Present (Discriminant_Specifications
13801 (Parent (Non_Limited_View (T)))))
13804 ("(Ada 2005) incomplete subtype may not be constrained", C);
13806 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13809 Fixup_Bad_Constraint;
13812 -- Check that the type has visible discriminants. The type may be
13813 -- a private type with unknown discriminants whose full view has
13814 -- discriminants which are invisible.
13816 elsif not Has_Discriminants (T)
13818 (Has_Unknown_Discriminants (T)
13819 and then Is_Private_Type (T))
13821 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13822 Fixup_Bad_Constraint;
13825 elsif Is_Constrained (E)
13826 or else (Ekind (E) = E_Class_Wide_Subtype
13827 and then Present (Discriminant_Constraint (E)))
13829 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13830 Fixup_Bad_Constraint;
13834 -- T may be an unconstrained subtype (e.g. a generic actual). Constraint
13835 -- applies to the base type.
13837 T := Base_Type (T);
13839 Constr := Build_Discriminant_Constraints (T, S);
13841 -- If the list returned was empty we had an error in building the
13842 -- discriminant constraint. We have also already signalled an error
13843 -- in the incomplete type case
13845 if Is_Empty_Elmt_List (Constr) then
13846 Fixup_Bad_Constraint;
13850 Build_Discriminated_Subtype (T, Def_Id, Constr, Related_Nod, For_Access);
13851 end Constrain_Discriminated_Type;
13853 ---------------------------
13854 -- Constrain_Enumeration --
13855 ---------------------------
13857 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13858 T : constant Entity_Id := Entity (Subtype_Mark (S));
13859 C : constant Node_Id := Constraint (S);
13862 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13864 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13866 Set_Etype (Def_Id, Base_Type (T));
13867 Set_Size_Info (Def_Id, (T));
13868 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13869 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13871 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13873 Set_Discrete_RM_Size (Def_Id);
13874 end Constrain_Enumeration;
13876 ----------------------
13877 -- Constrain_Float --
13878 ----------------------
13880 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13881 T : constant Entity_Id := Entity (Subtype_Mark (S));
13887 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13889 Set_Etype (Def_Id, Base_Type (T));
13890 Set_Size_Info (Def_Id, (T));
13891 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13893 -- Process the constraint
13895 C := Constraint (S);
13897 -- Digits constraint present
13899 if Nkind (C) = N_Digits_Constraint then
13901 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13902 Check_Restriction (No_Obsolescent_Features, C);
13904 if Warn_On_Obsolescent_Feature then
13906 ("subtype digits constraint is an " &
13907 "obsolescent feature (RM J.3(8))?j?", C);
13910 D := Digits_Expression (C);
13911 Analyze_And_Resolve (D, Any_Integer);
13912 Check_Digits_Expression (D);
13913 Set_Digits_Value (Def_Id, Expr_Value (D));
13915 -- Check that digits value is in range. Obviously we can do this
13916 -- at compile time, but it is strictly a runtime check, and of
13917 -- course there is an ACVC test that checks this.
13919 if Digits_Value (Def_Id) > Digits_Value (T) then
13920 Error_Msg_Uint_1 := Digits_Value (T);
13921 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13923 Make_Raise_Constraint_Error (Sloc (D),
13924 Reason => CE_Range_Check_Failed);
13925 Insert_Action (Declaration_Node (Def_Id), Rais);
13928 C := Range_Constraint (C);
13930 -- No digits constraint present
13933 Set_Digits_Value (Def_Id, Digits_Value (T));
13936 -- Range constraint present
13938 if Nkind (C) = N_Range_Constraint then
13939 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13941 -- No range constraint present
13944 pragma Assert (No (C));
13945 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13948 Set_Is_Constrained (Def_Id);
13949 end Constrain_Float;
13951 ---------------------
13952 -- Constrain_Index --
13953 ---------------------
13955 procedure Constrain_Index
13958 Related_Nod : Node_Id;
13959 Related_Id : Entity_Id;
13960 Suffix : Character;
13961 Suffix_Index : Nat)
13963 Def_Id : Entity_Id;
13964 R : Node_Id := Empty;
13965 T : constant Entity_Id := Etype (Index);
13969 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13970 Set_Etype (Def_Id, Base_Type (T));
13972 if Nkind (S) = N_Range
13974 (Nkind (S) = N_Attribute_Reference
13975 and then Attribute_Name (S) = Name_Range)
13977 -- A Range attribute will be transformed into N_Range by Resolve
13983 Process_Range_Expr_In_Decl (R, T);
13985 if not Error_Posted (S)
13987 (Nkind (S) /= N_Range
13988 or else not Covers (T, (Etype (Low_Bound (S))))
13989 or else not Covers (T, (Etype (High_Bound (S)))))
13991 if Base_Type (T) /= Any_Type
13992 and then Etype (Low_Bound (S)) /= Any_Type
13993 and then Etype (High_Bound (S)) /= Any_Type
13995 Error_Msg_N ("range expected", S);
13999 elsif Nkind (S) = N_Subtype_Indication then
14001 -- The parser has verified that this is a discrete indication
14003 Resolve_Discrete_Subtype_Indication (S, T);
14004 Bad_Predicated_Subtype_Use
14005 ("subtype& has predicate, not allowed in index constraint",
14006 S, Entity (Subtype_Mark (S)));
14008 R := Range_Expression (Constraint (S));
14010 -- Capture values of bounds and generate temporaries for them if
14011 -- needed, since checks may cause duplication of the expressions
14012 -- which must not be reevaluated.
14014 -- The forced evaluation removes side effects from expressions, which
14015 -- should occur also in GNATprove mode. Otherwise, we end up with
14016 -- unexpected insertions of actions at places where this is not
14017 -- supposed to occur, e.g. on default parameters of a call.
14019 if Expander_Active or GNATprove_Mode then
14021 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
14023 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
14026 elsif Nkind (S) = N_Discriminant_Association then
14028 -- Syntactically valid in subtype indication
14030 Error_Msg_N ("invalid index constraint", S);
14031 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
14034 -- Subtype_Mark case, no anonymous subtypes to construct
14039 if Is_Entity_Name (S) then
14040 if not Is_Type (Entity (S)) then
14041 Error_Msg_N ("expect subtype mark for index constraint", S);
14043 elsif Base_Type (Entity (S)) /= Base_Type (T) then
14044 Wrong_Type (S, Base_Type (T));
14046 -- Check error of subtype with predicate in index constraint
14049 Bad_Predicated_Subtype_Use
14050 ("subtype& has predicate, not allowed in index constraint",
14057 Error_Msg_N ("invalid index constraint", S);
14058 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
14063 -- Complete construction of the Itype
14065 if Is_Modular_Integer_Type (T) then
14066 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
14068 elsif Is_Integer_Type (T) then
14069 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
14072 Set_Ekind (Def_Id, E_Enumeration_Subtype);
14073 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
14074 Set_First_Literal (Def_Id, First_Literal (T));
14077 Set_Size_Info (Def_Id, (T));
14078 Set_RM_Size (Def_Id, RM_Size (T));
14079 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
14081 Set_Scalar_Range (Def_Id, R);
14083 Set_Etype (S, Def_Id);
14084 Set_Discrete_RM_Size (Def_Id);
14085 end Constrain_Index;
14087 -----------------------
14088 -- Constrain_Integer --
14089 -----------------------
14091 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
14092 T : constant Entity_Id := Entity (Subtype_Mark (S));
14093 C : constant Node_Id := Constraint (S);
14096 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
14098 if Is_Modular_Integer_Type (T) then
14099 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
14101 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
14104 Set_Etype (Def_Id, Base_Type (T));
14105 Set_Size_Info (Def_Id, (T));
14106 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
14107 Set_Discrete_RM_Size (Def_Id);
14108 end Constrain_Integer;
14110 ------------------------------
14111 -- Constrain_Ordinary_Fixed --
14112 ------------------------------
14114 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
14115 T : constant Entity_Id := Entity (Subtype_Mark (S));
14121 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
14122 Set_Etype (Def_Id, Base_Type (T));
14123 Set_Size_Info (Def_Id, (T));
14124 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
14125 Set_Small_Value (Def_Id, Small_Value (T));
14127 -- Process the constraint
14129 C := Constraint (S);
14131 -- Delta constraint present
14133 if Nkind (C) = N_Delta_Constraint then
14135 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
14136 Check_Restriction (No_Obsolescent_Features, C);
14138 if Warn_On_Obsolescent_Feature then
14140 ("subtype delta constraint is an " &
14141 "obsolescent feature (RM J.3(7))?j?");
14144 D := Delta_Expression (C);
14145 Analyze_And_Resolve (D, Any_Real);
14146 Check_Delta_Expression (D);
14147 Set_Delta_Value (Def_Id, Expr_Value_R (D));
14149 -- Check that delta value is in range. Obviously we can do this
14150 -- at compile time, but it is strictly a runtime check, and of
14151 -- course there is an ACVC test that checks this.
14153 if Delta_Value (Def_Id) < Delta_Value (T) then
14154 Error_Msg_N ("??delta value is too small", D);
14156 Make_Raise_Constraint_Error (Sloc (D),
14157 Reason => CE_Range_Check_Failed);
14158 Insert_Action (Declaration_Node (Def_Id), Rais);
14161 C := Range_Constraint (C);
14163 -- No delta constraint present
14166 Set_Delta_Value (Def_Id, Delta_Value (T));
14169 -- Range constraint present
14171 if Nkind (C) = N_Range_Constraint then
14172 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
14174 -- No range constraint present
14177 pragma Assert (No (C));
14178 Set_Scalar_Range (Def_Id, Scalar_Range (T));
14181 Set_Discrete_RM_Size (Def_Id);
14183 -- Unconditionally delay the freeze, since we cannot set size
14184 -- information in all cases correctly until the freeze point.
14186 Set_Has_Delayed_Freeze (Def_Id);
14187 end Constrain_Ordinary_Fixed;
14189 -----------------------
14190 -- Contain_Interface --
14191 -----------------------
14193 function Contain_Interface
14194 (Iface : Entity_Id;
14195 Ifaces : Elist_Id) return Boolean
14197 Iface_Elmt : Elmt_Id;
14200 if Present (Ifaces) then
14201 Iface_Elmt := First_Elmt (Ifaces);
14202 while Present (Iface_Elmt) loop
14203 if Node (Iface_Elmt) = Iface then
14207 Next_Elmt (Iface_Elmt);
14212 end Contain_Interface;
14214 ---------------------------
14215 -- Convert_Scalar_Bounds --
14216 ---------------------------
14218 procedure Convert_Scalar_Bounds
14220 Parent_Type : Entity_Id;
14221 Derived_Type : Entity_Id;
14224 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
14231 -- Defend against previous errors
14233 if No (Scalar_Range (Derived_Type)) then
14234 Check_Error_Detected;
14238 Lo := Build_Scalar_Bound
14239 (Type_Low_Bound (Derived_Type),
14240 Parent_Type, Implicit_Base);
14242 Hi := Build_Scalar_Bound
14243 (Type_High_Bound (Derived_Type),
14244 Parent_Type, Implicit_Base);
14251 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
14253 Set_Parent (Rng, N);
14254 Set_Scalar_Range (Derived_Type, Rng);
14256 -- Analyze the bounds
14258 Analyze_And_Resolve (Lo, Implicit_Base);
14259 Analyze_And_Resolve (Hi, Implicit_Base);
14261 -- Analyze the range itself, except that we do not analyze it if
14262 -- the bounds are real literals, and we have a fixed-point type.
14263 -- The reason for this is that we delay setting the bounds in this
14264 -- case till we know the final Small and Size values (see circuit
14265 -- in Freeze.Freeze_Fixed_Point_Type for further details).
14267 if Is_Fixed_Point_Type (Parent_Type)
14268 and then Nkind (Lo) = N_Real_Literal
14269 and then Nkind (Hi) = N_Real_Literal
14273 -- Here we do the analysis of the range
14275 -- Note: we do this manually, since if we do a normal Analyze and
14276 -- Resolve call, there are problems with the conversions used for
14277 -- the derived type range.
14280 Set_Etype (Rng, Implicit_Base);
14281 Set_Analyzed (Rng, True);
14283 end Convert_Scalar_Bounds;
14285 -------------------
14286 -- Copy_And_Swap --
14287 -------------------
14289 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
14291 -- Initialize new full declaration entity by copying the pertinent
14292 -- fields of the corresponding private declaration entity.
14294 -- We temporarily set Ekind to a value appropriate for a type to
14295 -- avoid assert failures in Einfo from checking for setting type
14296 -- attributes on something that is not a type. Ekind (Priv) is an
14297 -- appropriate choice, since it allowed the attributes to be set
14298 -- in the first place. This Ekind value will be modified later.
14300 Set_Ekind (Full, Ekind (Priv));
14302 -- Also set Etype temporarily to Any_Type, again, in the absence
14303 -- of errors, it will be properly reset, and if there are errors,
14304 -- then we want a value of Any_Type to remain.
14306 Set_Etype (Full, Any_Type);
14308 -- Now start copying attributes
14310 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
14312 if Has_Discriminants (Full) then
14313 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
14314 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
14317 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
14318 Set_Homonym (Full, Homonym (Priv));
14319 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
14320 Set_Is_Public (Full, Is_Public (Priv));
14321 Set_Is_Pure (Full, Is_Pure (Priv));
14322 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
14323 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
14324 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
14325 Set_Has_Pragma_Unreferenced_Objects
14326 (Full, Has_Pragma_Unreferenced_Objects
14329 Conditional_Delay (Full, Priv);
14331 if Is_Tagged_Type (Full) then
14332 Set_Direct_Primitive_Operations
14333 (Full, Direct_Primitive_Operations (Priv));
14334 Set_No_Tagged_Streams_Pragma
14335 (Full, No_Tagged_Streams_Pragma (Priv));
14337 if Is_Base_Type (Priv) then
14338 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
14342 Set_Is_Volatile (Full, Is_Volatile (Priv));
14343 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
14344 Set_Scope (Full, Scope (Priv));
14345 Set_Next_Entity (Full, Next_Entity (Priv));
14346 Set_First_Entity (Full, First_Entity (Priv));
14347 Set_Last_Entity (Full, Last_Entity (Priv));
14349 -- If access types have been recorded for later handling, keep them in
14350 -- the full view so that they get handled when the full view freeze
14351 -- node is expanded.
14353 if Present (Freeze_Node (Priv))
14354 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
14356 Ensure_Freeze_Node (Full);
14357 Set_Access_Types_To_Process
14358 (Freeze_Node (Full),
14359 Access_Types_To_Process (Freeze_Node (Priv)));
14362 -- Swap the two entities. Now Private is the full type entity and Full
14363 -- is the private one. They will be swapped back at the end of the
14364 -- private part. This swapping ensures that the entity that is visible
14365 -- in the private part is the full declaration.
14367 Exchange_Entities (Priv, Full);
14368 Append_Entity (Full, Scope (Full));
14371 -------------------------------------
14372 -- Copy_Array_Base_Type_Attributes --
14373 -------------------------------------
14375 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
14377 Set_Component_Alignment (T1, Component_Alignment (T2));
14378 Set_Component_Type (T1, Component_Type (T2));
14379 Set_Component_Size (T1, Component_Size (T2));
14380 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
14381 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
14382 Propagate_Concurrent_Flags (T1, T2);
14383 Set_Is_Packed (T1, Is_Packed (T2));
14384 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
14385 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
14386 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
14387 end Copy_Array_Base_Type_Attributes;
14389 -----------------------------------
14390 -- Copy_Array_Subtype_Attributes --
14391 -----------------------------------
14393 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
14395 Set_Size_Info (T1, T2);
14397 Set_First_Index (T1, First_Index (T2));
14398 Set_Is_Aliased (T1, Is_Aliased (T2));
14399 Set_Is_Volatile (T1, Is_Volatile (T2));
14400 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
14401 Set_Is_Constrained (T1, Is_Constrained (T2));
14402 Set_Depends_On_Private (T1, Has_Private_Component (T2));
14403 Inherit_Rep_Item_Chain (T1, T2);
14404 Set_Convention (T1, Convention (T2));
14405 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
14406 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
14407 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
14408 end Copy_Array_Subtype_Attributes;
14410 -----------------------------------
14411 -- Create_Constrained_Components --
14412 -----------------------------------
14414 procedure Create_Constrained_Components
14416 Decl_Node : Node_Id;
14418 Constraints : Elist_Id)
14420 Loc : constant Source_Ptr := Sloc (Subt);
14421 Comp_List : constant Elist_Id := New_Elmt_List;
14422 Parent_Type : constant Entity_Id := Etype (Typ);
14423 Assoc_List : constant List_Id := New_List;
14424 Discr_Val : Elmt_Id;
14428 Is_Static : Boolean := True;
14430 procedure Collect_Fixed_Components (Typ : Entity_Id);
14431 -- Collect parent type components that do not appear in a variant part
14433 procedure Create_All_Components;
14434 -- Iterate over Comp_List to create the components of the subtype
14436 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
14437 -- Creates a new component from Old_Compon, copying all the fields from
14438 -- it, including its Etype, inserts the new component in the Subt entity
14439 -- chain and returns the new component.
14441 function Is_Variant_Record (T : Entity_Id) return Boolean;
14442 -- If true, and discriminants are static, collect only components from
14443 -- variants selected by discriminant values.
14445 ------------------------------
14446 -- Collect_Fixed_Components --
14447 ------------------------------
14449 procedure Collect_Fixed_Components (Typ : Entity_Id) is
14451 -- Build association list for discriminants, and find components of the
14452 -- variant part selected by the values of the discriminants.
14454 Old_C := First_Discriminant (Typ);
14455 Discr_Val := First_Elmt (Constraints);
14456 while Present (Old_C) loop
14457 Append_To (Assoc_List,
14458 Make_Component_Association (Loc,
14459 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
14460 Expression => New_Copy (Node (Discr_Val))));
14462 Next_Elmt (Discr_Val);
14463 Next_Discriminant (Old_C);
14466 -- The tag and the possible parent component are unconditionally in
14469 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
14470 Old_C := First_Component (Typ);
14471 while Present (Old_C) loop
14472 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
14473 Append_Elmt (Old_C, Comp_List);
14476 Next_Component (Old_C);
14479 end Collect_Fixed_Components;
14481 ---------------------------
14482 -- Create_All_Components --
14483 ---------------------------
14485 procedure Create_All_Components is
14489 Comp := First_Elmt (Comp_List);
14490 while Present (Comp) loop
14491 Old_C := Node (Comp);
14492 New_C := Create_Component (Old_C);
14496 Constrain_Component_Type
14497 (Old_C, Subt, Decl_Node, Typ, Constraints));
14498 Set_Is_Public (New_C, Is_Public (Subt));
14502 end Create_All_Components;
14504 ----------------------
14505 -- Create_Component --
14506 ----------------------
14508 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
14509 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
14512 if Ekind (Old_Compon) = E_Discriminant
14513 and then Is_Completely_Hidden (Old_Compon)
14515 -- This is a shadow discriminant created for a discriminant of
14516 -- the parent type, which needs to be present in the subtype.
14517 -- Give the shadow discriminant an internal name that cannot
14518 -- conflict with that of visible components.
14520 Set_Chars (New_Compon, New_Internal_Name ('C'));
14523 -- Set the parent so we have a proper link for freezing etc. This is
14524 -- not a real parent pointer, since of course our parent does not own
14525 -- up to us and reference us, we are an illegitimate child of the
14526 -- original parent.
14528 Set_Parent (New_Compon, Parent (Old_Compon));
14530 -- We do not want this node marked as Comes_From_Source, since
14531 -- otherwise it would get first class status and a separate cross-
14532 -- reference line would be generated. Illegitimate children do not
14533 -- rate such recognition.
14535 Set_Comes_From_Source (New_Compon, False);
14537 -- But it is a real entity, and a birth certificate must be properly
14538 -- registered by entering it into the entity list.
14540 Enter_Name (New_Compon);
14543 end Create_Component;
14545 -----------------------
14546 -- Is_Variant_Record --
14547 -----------------------
14549 function Is_Variant_Record (T : Entity_Id) return Boolean is
14551 return Nkind (Parent (T)) = N_Full_Type_Declaration
14552 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
14553 and then Present (Component_List (Type_Definition (Parent (T))))
14556 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
14557 end Is_Variant_Record;
14559 -- Start of processing for Create_Constrained_Components
14562 pragma Assert (Subt /= Base_Type (Subt));
14563 pragma Assert (Typ = Base_Type (Typ));
14565 Set_First_Entity (Subt, Empty);
14566 Set_Last_Entity (Subt, Empty);
14568 -- Check whether constraint is fully static, in which case we can
14569 -- optimize the list of components.
14571 Discr_Val := First_Elmt (Constraints);
14572 while Present (Discr_Val) loop
14573 if not Is_OK_Static_Expression (Node (Discr_Val)) then
14574 Is_Static := False;
14578 Next_Elmt (Discr_Val);
14581 Set_Has_Static_Discriminants (Subt, Is_Static);
14585 -- Inherit the discriminants of the parent type
14587 Add_Discriminants : declare
14593 Old_C := First_Discriminant (Typ);
14595 while Present (Old_C) loop
14596 Num_Disc := Num_Disc + 1;
14597 New_C := Create_Component (Old_C);
14598 Set_Is_Public (New_C, Is_Public (Subt));
14599 Next_Discriminant (Old_C);
14602 -- For an untagged derived subtype, the number of discriminants may
14603 -- be smaller than the number of inherited discriminants, because
14604 -- several of them may be renamed by a single new discriminant or
14605 -- constrained. In this case, add the hidden discriminants back into
14606 -- the subtype, because they need to be present if the optimizer of
14607 -- the GCC 4.x back-end decides to break apart assignments between
14608 -- objects using the parent view into member-wise assignments.
14612 if Is_Derived_Type (Typ)
14613 and then not Is_Tagged_Type (Typ)
14615 Old_C := First_Stored_Discriminant (Typ);
14617 while Present (Old_C) loop
14618 Num_Gird := Num_Gird + 1;
14619 Next_Stored_Discriminant (Old_C);
14623 if Num_Gird > Num_Disc then
14625 -- Find out multiple uses of new discriminants, and add hidden
14626 -- components for the extra renamed discriminants. We recognize
14627 -- multiple uses through the Corresponding_Discriminant of a
14628 -- new discriminant: if it constrains several old discriminants,
14629 -- this field points to the last one in the parent type. The
14630 -- stored discriminants of the derived type have the same name
14631 -- as those of the parent.
14635 New_Discr : Entity_Id;
14636 Old_Discr : Entity_Id;
14639 Constr := First_Elmt (Stored_Constraint (Typ));
14640 Old_Discr := First_Stored_Discriminant (Typ);
14641 while Present (Constr) loop
14642 if Is_Entity_Name (Node (Constr))
14643 and then Ekind (Entity (Node (Constr))) = E_Discriminant
14645 New_Discr := Entity (Node (Constr));
14647 if Chars (Corresponding_Discriminant (New_Discr)) /=
14650 -- The new discriminant has been used to rename a
14651 -- subsequent old discriminant. Introduce a shadow
14652 -- component for the current old discriminant.
14654 New_C := Create_Component (Old_Discr);
14655 Set_Original_Record_Component (New_C, Old_Discr);
14659 -- The constraint has eliminated the old discriminant.
14660 -- Introduce a shadow component.
14662 New_C := Create_Component (Old_Discr);
14663 Set_Original_Record_Component (New_C, Old_Discr);
14666 Next_Elmt (Constr);
14667 Next_Stored_Discriminant (Old_Discr);
14671 end Add_Discriminants;
14674 and then Is_Variant_Record (Typ)
14676 Collect_Fixed_Components (Typ);
14678 Gather_Components (
14680 Component_List (Type_Definition (Parent (Typ))),
14681 Governed_By => Assoc_List,
14683 Report_Errors => Errors);
14684 pragma Assert (not Errors
14685 or else Serious_Errors_Detected > 0);
14687 Create_All_Components;
14689 -- If the subtype declaration is created for a tagged type derivation
14690 -- with constraints, we retrieve the record definition of the parent
14691 -- type to select the components of the proper variant.
14694 and then Is_Tagged_Type (Typ)
14695 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14697 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14698 and then Is_Variant_Record (Parent_Type)
14700 Collect_Fixed_Components (Typ);
14704 Component_List (Type_Definition (Parent (Parent_Type))),
14705 Governed_By => Assoc_List,
14707 Report_Errors => Errors);
14709 -- Note: previously there was a check at this point that no errors
14710 -- were detected. As a consequence of AI05-220 there may be an error
14711 -- if an inherited discriminant that controls a variant has a non-
14712 -- static constraint.
14714 -- If the tagged derivation has a type extension, collect all the
14715 -- new components therein.
14717 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14719 Old_C := First_Component (Typ);
14720 while Present (Old_C) loop
14721 if Original_Record_Component (Old_C) = Old_C
14722 and then Chars (Old_C) /= Name_uTag
14723 and then Chars (Old_C) /= Name_uParent
14725 Append_Elmt (Old_C, Comp_List);
14728 Next_Component (Old_C);
14732 Create_All_Components;
14735 -- If discriminants are not static, or if this is a multi-level type
14736 -- extension, we have to include all components of the parent type.
14738 Old_C := First_Component (Typ);
14739 while Present (Old_C) loop
14740 New_C := Create_Component (Old_C);
14744 Constrain_Component_Type
14745 (Old_C, Subt, Decl_Node, Typ, Constraints));
14746 Set_Is_Public (New_C, Is_Public (Subt));
14748 Next_Component (Old_C);
14753 end Create_Constrained_Components;
14755 ------------------------------------------
14756 -- Decimal_Fixed_Point_Type_Declaration --
14757 ------------------------------------------
14759 procedure Decimal_Fixed_Point_Type_Declaration
14763 Loc : constant Source_Ptr := Sloc (Def);
14764 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14765 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14766 Implicit_Base : Entity_Id;
14773 Check_SPARK_05_Restriction
14774 ("decimal fixed point type is not allowed", Def);
14775 Check_Restriction (No_Fixed_Point, Def);
14777 -- Create implicit base type
14780 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14781 Set_Etype (Implicit_Base, Implicit_Base);
14783 -- Analyze and process delta expression
14785 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14787 Check_Delta_Expression (Delta_Expr);
14788 Delta_Val := Expr_Value_R (Delta_Expr);
14790 -- Check delta is power of 10, and determine scale value from it
14796 Scale_Val := Uint_0;
14799 if Val < Ureal_1 then
14800 while Val < Ureal_1 loop
14801 Val := Val * Ureal_10;
14802 Scale_Val := Scale_Val + 1;
14805 if Scale_Val > 18 then
14806 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14807 Scale_Val := UI_From_Int (+18);
14811 while Val > Ureal_1 loop
14812 Val := Val / Ureal_10;
14813 Scale_Val := Scale_Val - 1;
14816 if Scale_Val < -18 then
14817 Error_Msg_N ("scale is less than minimum value of -18", Def);
14818 Scale_Val := UI_From_Int (-18);
14822 if Val /= Ureal_1 then
14823 Error_Msg_N ("delta expression must be a power of 10", Def);
14824 Delta_Val := Ureal_10 ** (-Scale_Val);
14828 -- Set delta, scale and small (small = delta for decimal type)
14830 Set_Delta_Value (Implicit_Base, Delta_Val);
14831 Set_Scale_Value (Implicit_Base, Scale_Val);
14832 Set_Small_Value (Implicit_Base, Delta_Val);
14834 -- Analyze and process digits expression
14836 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14837 Check_Digits_Expression (Digs_Expr);
14838 Digs_Val := Expr_Value (Digs_Expr);
14840 if Digs_Val > 18 then
14841 Digs_Val := UI_From_Int (+18);
14842 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14845 Set_Digits_Value (Implicit_Base, Digs_Val);
14846 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14848 -- Set range of base type from digits value for now. This will be
14849 -- expanded to represent the true underlying base range by Freeze.
14851 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14853 -- Note: We leave size as zero for now, size will be set at freeze
14854 -- time. We have to do this for ordinary fixed-point, because the size
14855 -- depends on the specified small, and we might as well do the same for
14856 -- decimal fixed-point.
14858 pragma Assert (Esize (Implicit_Base) = Uint_0);
14860 -- If there are bounds given in the declaration use them as the
14861 -- bounds of the first named subtype.
14863 if Present (Real_Range_Specification (Def)) then
14865 RRS : constant Node_Id := Real_Range_Specification (Def);
14866 Low : constant Node_Id := Low_Bound (RRS);
14867 High : constant Node_Id := High_Bound (RRS);
14872 Analyze_And_Resolve (Low, Any_Real);
14873 Analyze_And_Resolve (High, Any_Real);
14874 Check_Real_Bound (Low);
14875 Check_Real_Bound (High);
14876 Low_Val := Expr_Value_R (Low);
14877 High_Val := Expr_Value_R (High);
14879 if Low_Val < (-Bound_Val) then
14881 ("range low bound too small for digits value", Low);
14882 Low_Val := -Bound_Val;
14885 if High_Val > Bound_Val then
14887 ("range high bound too large for digits value", High);
14888 High_Val := Bound_Val;
14891 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14894 -- If no explicit range, use range that corresponds to given
14895 -- digits value. This will end up as the final range for the
14899 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14902 -- Complete entity for first subtype. The inheritance of the rep item
14903 -- chain ensures that SPARK-related pragmas are not clobbered when the
14904 -- decimal fixed point type acts as a full view of a private type.
14906 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14907 Set_Etype (T, Implicit_Base);
14908 Set_Size_Info (T, Implicit_Base);
14909 Inherit_Rep_Item_Chain (T, Implicit_Base);
14910 Set_Digits_Value (T, Digs_Val);
14911 Set_Delta_Value (T, Delta_Val);
14912 Set_Small_Value (T, Delta_Val);
14913 Set_Scale_Value (T, Scale_Val);
14914 Set_Is_Constrained (T);
14915 end Decimal_Fixed_Point_Type_Declaration;
14917 -----------------------------------
14918 -- Derive_Progenitor_Subprograms --
14919 -----------------------------------
14921 procedure Derive_Progenitor_Subprograms
14922 (Parent_Type : Entity_Id;
14923 Tagged_Type : Entity_Id)
14928 Iface_Elmt : Elmt_Id;
14929 Iface_Subp : Entity_Id;
14930 New_Subp : Entity_Id := Empty;
14931 Prim_Elmt : Elmt_Id;
14936 pragma Assert (Ada_Version >= Ada_2005
14937 and then Is_Record_Type (Tagged_Type)
14938 and then Is_Tagged_Type (Tagged_Type)
14939 and then Has_Interfaces (Tagged_Type));
14941 -- Step 1: Transfer to the full-view primitives associated with the
14942 -- partial-view that cover interface primitives. Conceptually this
14943 -- work should be done later by Process_Full_View; done here to
14944 -- simplify its implementation at later stages. It can be safely
14945 -- done here because interfaces must be visible in the partial and
14946 -- private view (RM 7.3(7.3/2)).
14948 -- Small optimization: This work is only required if the parent may
14949 -- have entities whose Alias attribute reference an interface primitive.
14950 -- Such a situation may occur if the parent is an abstract type and the
14951 -- primitive has not been yet overridden or if the parent is a generic
14952 -- formal type covering interfaces.
14954 -- If the tagged type is not abstract, it cannot have abstract
14955 -- primitives (the only entities in the list of primitives of
14956 -- non-abstract tagged types that can reference abstract primitives
14957 -- through its Alias attribute are the internal entities that have
14958 -- attribute Interface_Alias, and these entities are generated later
14959 -- by Add_Internal_Interface_Entities).
14961 if In_Private_Part (Current_Scope)
14962 and then (Is_Abstract_Type (Parent_Type)
14964 Is_Generic_Type (Parent_Type))
14966 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14967 while Present (Elmt) loop
14968 Subp := Node (Elmt);
14970 -- At this stage it is not possible to have entities in the list
14971 -- of primitives that have attribute Interface_Alias.
14973 pragma Assert (No (Interface_Alias (Subp)));
14975 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14977 if Is_Interface (Typ) then
14978 E := Find_Primitive_Covering_Interface
14979 (Tagged_Type => Tagged_Type,
14980 Iface_Prim => Subp);
14983 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14985 Replace_Elmt (Elmt, E);
14986 Remove_Homonym (Subp);
14994 -- Step 2: Add primitives of progenitors that are not implemented by
14995 -- parents of Tagged_Type.
14997 if Present (Interfaces (Base_Type (Tagged_Type))) then
14998 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14999 while Present (Iface_Elmt) loop
15000 Iface := Node (Iface_Elmt);
15002 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
15003 while Present (Prim_Elmt) loop
15004 Iface_Subp := Node (Prim_Elmt);
15006 -- Exclude derivation of predefined primitives except those
15007 -- that come from source, or are inherited from one that comes
15008 -- from source. Required to catch declarations of equality
15009 -- operators of interfaces. For example:
15011 -- type Iface is interface;
15012 -- function "=" (Left, Right : Iface) return Boolean;
15014 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
15015 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
15017 E := Find_Primitive_Covering_Interface
15018 (Tagged_Type => Tagged_Type,
15019 Iface_Prim => Iface_Subp);
15021 -- If not found we derive a new primitive leaving its alias
15022 -- attribute referencing the interface primitive.
15026 (New_Subp, Iface_Subp, Tagged_Type, Iface);
15028 -- Ada 2012 (AI05-0197): If the covering primitive's name
15029 -- differs from the name of the interface primitive then it
15030 -- is a private primitive inherited from a parent type. In
15031 -- such case, given that Tagged_Type covers the interface,
15032 -- the inherited private primitive becomes visible. For such
15033 -- purpose we add a new entity that renames the inherited
15034 -- private primitive.
15036 elsif Chars (E) /= Chars (Iface_Subp) then
15037 pragma Assert (Has_Suffix (E, 'P'));
15039 (New_Subp, Iface_Subp, Tagged_Type, Iface);
15040 Set_Alias (New_Subp, E);
15041 Set_Is_Abstract_Subprogram (New_Subp,
15042 Is_Abstract_Subprogram (E));
15044 -- Propagate to the full view interface entities associated
15045 -- with the partial view.
15047 elsif In_Private_Part (Current_Scope)
15048 and then Present (Alias (E))
15049 and then Alias (E) = Iface_Subp
15051 List_Containing (Parent (E)) /=
15052 Private_Declarations
15054 (Unit_Declaration_Node (Current_Scope)))
15056 Append_Elmt (E, Primitive_Operations (Tagged_Type));
15060 Next_Elmt (Prim_Elmt);
15063 Next_Elmt (Iface_Elmt);
15066 end Derive_Progenitor_Subprograms;
15068 -----------------------
15069 -- Derive_Subprogram --
15070 -----------------------
15072 procedure Derive_Subprogram
15073 (New_Subp : out Entity_Id;
15074 Parent_Subp : Entity_Id;
15075 Derived_Type : Entity_Id;
15076 Parent_Type : Entity_Id;
15077 Actual_Subp : Entity_Id := Empty)
15079 Formal : Entity_Id;
15080 -- Formal parameter of parent primitive operation
15082 Formal_Of_Actual : Entity_Id;
15083 -- Formal parameter of actual operation, when the derivation is to
15084 -- create a renaming for a primitive operation of an actual in an
15087 New_Formal : Entity_Id;
15088 -- Formal of inherited operation
15090 Visible_Subp : Entity_Id := Parent_Subp;
15092 function Is_Private_Overriding return Boolean;
15093 -- If Subp is a private overriding of a visible operation, the inherited
15094 -- operation derives from the overridden op (even though its body is the
15095 -- overriding one) and the inherited operation is visible now. See
15096 -- sem_disp to see the full details of the handling of the overridden
15097 -- subprogram, which is removed from the list of primitive operations of
15098 -- the type. The overridden subprogram is saved locally in Visible_Subp,
15099 -- and used to diagnose abstract operations that need overriding in the
15102 procedure Replace_Type (Id, New_Id : Entity_Id);
15103 -- When the type is an anonymous access type, create a new access type
15104 -- designating the derived type.
15106 procedure Set_Derived_Name;
15107 -- This procedure sets the appropriate Chars name for New_Subp. This
15108 -- is normally just a copy of the parent name. An exception arises for
15109 -- type support subprograms, where the name is changed to reflect the
15110 -- name of the derived type, e.g. if type foo is derived from type bar,
15111 -- then a procedure barDA is derived with a name fooDA.
15113 ---------------------------
15114 -- Is_Private_Overriding --
15115 ---------------------------
15117 function Is_Private_Overriding return Boolean is
15121 -- If the parent is not a dispatching operation there is no
15122 -- need to investigate overridings
15124 if not Is_Dispatching_Operation (Parent_Subp) then
15128 -- The visible operation that is overridden is a homonym of the
15129 -- parent subprogram. We scan the homonym chain to find the one
15130 -- whose alias is the subprogram we are deriving.
15132 Prev := Current_Entity (Parent_Subp);
15133 while Present (Prev) loop
15134 if Ekind (Prev) = Ekind (Parent_Subp)
15135 and then Alias (Prev) = Parent_Subp
15136 and then Scope (Parent_Subp) = Scope (Prev)
15137 and then not Is_Hidden (Prev)
15139 Visible_Subp := Prev;
15143 Prev := Homonym (Prev);
15147 end Is_Private_Overriding;
15153 procedure Replace_Type (Id, New_Id : Entity_Id) is
15154 Id_Type : constant Entity_Id := Etype (Id);
15155 Acc_Type : Entity_Id;
15156 Par : constant Node_Id := Parent (Derived_Type);
15159 -- When the type is an anonymous access type, create a new access
15160 -- type designating the derived type. This itype must be elaborated
15161 -- at the point of the derivation, not on subsequent calls that may
15162 -- be out of the proper scope for Gigi, so we insert a reference to
15163 -- it after the derivation.
15165 if Ekind (Id_Type) = E_Anonymous_Access_Type then
15167 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
15170 if Ekind (Desig_Typ) = E_Record_Type_With_Private
15171 and then Present (Full_View (Desig_Typ))
15172 and then not Is_Private_Type (Parent_Type)
15174 Desig_Typ := Full_View (Desig_Typ);
15177 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
15179 -- Ada 2005 (AI-251): Handle also derivations of abstract
15180 -- interface primitives.
15182 or else (Is_Interface (Desig_Typ)
15183 and then not Is_Class_Wide_Type (Desig_Typ))
15185 Acc_Type := New_Copy (Id_Type);
15186 Set_Etype (Acc_Type, Acc_Type);
15187 Set_Scope (Acc_Type, New_Subp);
15189 -- Set size of anonymous access type. If we have an access
15190 -- to an unconstrained array, this is a fat pointer, so it
15191 -- is sizes at twice addtress size.
15193 if Is_Array_Type (Desig_Typ)
15194 and then not Is_Constrained (Desig_Typ)
15196 Init_Size (Acc_Type, 2 * System_Address_Size);
15198 -- Other cases use a thin pointer
15201 Init_Size (Acc_Type, System_Address_Size);
15204 -- Set remaining characterstics of anonymous access type
15206 Init_Alignment (Acc_Type);
15207 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
15209 Set_Etype (New_Id, Acc_Type);
15210 Set_Scope (New_Id, New_Subp);
15212 -- Create a reference to it
15214 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
15217 Set_Etype (New_Id, Id_Type);
15221 -- In Ada2012, a formal may have an incomplete type but the type
15222 -- derivation that inherits the primitive follows the full view.
15224 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
15226 (Ekind (Id_Type) = E_Record_Type_With_Private
15227 and then Present (Full_View (Id_Type))
15229 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
15231 (Ada_Version >= Ada_2012
15232 and then Ekind (Id_Type) = E_Incomplete_Type
15233 and then Full_View (Id_Type) = Parent_Type)
15235 -- Constraint checks on formals are generated during expansion,
15236 -- based on the signature of the original subprogram. The bounds
15237 -- of the derived type are not relevant, and thus we can use
15238 -- the base type for the formals. However, the return type may be
15239 -- used in a context that requires that the proper static bounds
15240 -- be used (a case statement, for example) and for those cases
15241 -- we must use the derived type (first subtype), not its base.
15243 -- If the derived_type_definition has no constraints, we know that
15244 -- the derived type has the same constraints as the first subtype
15245 -- of the parent, and we can also use it rather than its base,
15246 -- which can lead to more efficient code.
15248 if Etype (Id) = Parent_Type then
15249 if Is_Scalar_Type (Parent_Type)
15251 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
15253 Set_Etype (New_Id, Derived_Type);
15255 elsif Nkind (Par) = N_Full_Type_Declaration
15257 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
15260 (Subtype_Indication (Type_Definition (Par)))
15262 Set_Etype (New_Id, Derived_Type);
15265 Set_Etype (New_Id, Base_Type (Derived_Type));
15269 Set_Etype (New_Id, Base_Type (Derived_Type));
15273 Set_Etype (New_Id, Etype (Id));
15277 ----------------------
15278 -- Set_Derived_Name --
15279 ----------------------
15281 procedure Set_Derived_Name is
15282 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
15284 if Nm = TSS_Null then
15285 Set_Chars (New_Subp, Chars (Parent_Subp));
15287 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
15289 end Set_Derived_Name;
15291 -- Start of processing for Derive_Subprogram
15294 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
15295 Set_Ekind (New_Subp, Ekind (Parent_Subp));
15297 -- Check whether the inherited subprogram is a private operation that
15298 -- should be inherited but not yet made visible. Such subprograms can
15299 -- become visible at a later point (e.g., the private part of a public
15300 -- child unit) via Declare_Inherited_Private_Subprograms. If the
15301 -- following predicate is true, then this is not such a private
15302 -- operation and the subprogram simply inherits the name of the parent
15303 -- subprogram. Note the special check for the names of controlled
15304 -- operations, which are currently exempted from being inherited with
15305 -- a hidden name because they must be findable for generation of
15306 -- implicit run-time calls.
15308 if not Is_Hidden (Parent_Subp)
15309 or else Is_Internal (Parent_Subp)
15310 or else Is_Private_Overriding
15311 or else Is_Internal_Name (Chars (Parent_Subp))
15312 or else (Is_Controlled (Parent_Type)
15313 and then Nam_In (Chars (Parent_Subp), Name_Adjust,
15319 -- An inherited dispatching equality will be overridden by an internally
15320 -- generated one, or by an explicit one, so preserve its name and thus
15321 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
15322 -- private operation it may become invisible if the full view has
15323 -- progenitors, and the dispatch table will be malformed.
15324 -- We check that the type is limited to handle the anomalous declaration
15325 -- of Limited_Controlled, which is derived from a non-limited type, and
15326 -- which is handled specially elsewhere as well.
15328 elsif Chars (Parent_Subp) = Name_Op_Eq
15329 and then Is_Dispatching_Operation (Parent_Subp)
15330 and then Etype (Parent_Subp) = Standard_Boolean
15331 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
15333 Etype (First_Formal (Parent_Subp)) =
15334 Etype (Next_Formal (First_Formal (Parent_Subp)))
15338 -- If parent is hidden, this can be a regular derivation if the
15339 -- parent is immediately visible in a non-instantiating context,
15340 -- or if we are in the private part of an instance. This test
15341 -- should still be refined ???
15343 -- The test for In_Instance_Not_Visible avoids inheriting the derived
15344 -- operation as a non-visible operation in cases where the parent
15345 -- subprogram might not be visible now, but was visible within the
15346 -- original generic, so it would be wrong to make the inherited
15347 -- subprogram non-visible now. (Not clear if this test is fully
15348 -- correct; are there any cases where we should declare the inherited
15349 -- operation as not visible to avoid it being overridden, e.g., when
15350 -- the parent type is a generic actual with private primitives ???)
15352 -- (they should be treated the same as other private inherited
15353 -- subprograms, but it's not clear how to do this cleanly). ???
15355 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15356 and then Is_Immediately_Visible (Parent_Subp)
15357 and then not In_Instance)
15358 or else In_Instance_Not_Visible
15362 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
15363 -- overrides an interface primitive because interface primitives
15364 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
15366 elsif Ada_Version >= Ada_2005
15367 and then Is_Dispatching_Operation (Parent_Subp)
15368 and then Present (Covered_Interface_Op (Parent_Subp))
15372 -- Otherwise, the type is inheriting a private operation, so enter it
15373 -- with a special name so it can't be overridden.
15376 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
15379 Set_Parent (New_Subp, Parent (Derived_Type));
15381 if Present (Actual_Subp) then
15382 Replace_Type (Actual_Subp, New_Subp);
15384 Replace_Type (Parent_Subp, New_Subp);
15387 Conditional_Delay (New_Subp, Parent_Subp);
15389 -- If we are creating a renaming for a primitive operation of an
15390 -- actual of a generic derived type, we must examine the signature
15391 -- of the actual primitive, not that of the generic formal, which for
15392 -- example may be an interface. However the name and initial value
15393 -- of the inherited operation are those of the formal primitive.
15395 Formal := First_Formal (Parent_Subp);
15397 if Present (Actual_Subp) then
15398 Formal_Of_Actual := First_Formal (Actual_Subp);
15400 Formal_Of_Actual := Empty;
15403 while Present (Formal) loop
15404 New_Formal := New_Copy (Formal);
15406 -- Normally we do not go copying parents, but in the case of
15407 -- formals, we need to link up to the declaration (which is the
15408 -- parameter specification), and it is fine to link up to the
15409 -- original formal's parameter specification in this case.
15411 Set_Parent (New_Formal, Parent (Formal));
15412 Append_Entity (New_Formal, New_Subp);
15414 if Present (Formal_Of_Actual) then
15415 Replace_Type (Formal_Of_Actual, New_Formal);
15416 Next_Formal (Formal_Of_Actual);
15418 Replace_Type (Formal, New_Formal);
15421 Next_Formal (Formal);
15424 -- If this derivation corresponds to a tagged generic actual, then
15425 -- primitive operations rename those of the actual. Otherwise the
15426 -- primitive operations rename those of the parent type, If the parent
15427 -- renames an intrinsic operator, so does the new subprogram. We except
15428 -- concatenation, which is always properly typed, and does not get
15429 -- expanded as other intrinsic operations.
15431 if No (Actual_Subp) then
15432 if Is_Intrinsic_Subprogram (Parent_Subp) then
15433 Set_Is_Intrinsic_Subprogram (New_Subp);
15435 if Present (Alias (Parent_Subp))
15436 and then Chars (Parent_Subp) /= Name_Op_Concat
15438 Set_Alias (New_Subp, Alias (Parent_Subp));
15440 Set_Alias (New_Subp, Parent_Subp);
15444 Set_Alias (New_Subp, Parent_Subp);
15448 Set_Alias (New_Subp, Actual_Subp);
15451 -- Derived subprograms of a tagged type must inherit the convention
15452 -- of the parent subprogram (a requirement of AI-117). Derived
15453 -- subprograms of untagged types simply get convention Ada by default.
15455 -- If the derived type is a tagged generic formal type with unknown
15456 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
15458 -- However, if the type is derived from a generic formal, the further
15459 -- inherited subprogram has the convention of the non-generic ancestor.
15460 -- Otherwise there would be no way to override the operation.
15461 -- (This is subject to forthcoming ARG discussions).
15463 if Is_Tagged_Type (Derived_Type) then
15464 if Is_Generic_Type (Derived_Type)
15465 and then Has_Unknown_Discriminants (Derived_Type)
15467 Set_Convention (New_Subp, Convention_Intrinsic);
15470 if Is_Generic_Type (Parent_Type)
15471 and then Has_Unknown_Discriminants (Parent_Type)
15473 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
15475 Set_Convention (New_Subp, Convention (Parent_Subp));
15480 -- Predefined controlled operations retain their name even if the parent
15481 -- is hidden (see above), but they are not primitive operations if the
15482 -- ancestor is not visible, for example if the parent is a private
15483 -- extension completed with a controlled extension. Note that a full
15484 -- type that is controlled can break privacy: the flag Is_Controlled is
15485 -- set on both views of the type.
15487 if Is_Controlled (Parent_Type)
15488 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
15491 and then Is_Hidden (Parent_Subp)
15492 and then not Is_Visibly_Controlled (Parent_Type)
15494 Set_Is_Hidden (New_Subp);
15497 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
15498 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
15500 if Ekind (Parent_Subp) = E_Procedure then
15501 Set_Is_Valued_Procedure
15502 (New_Subp, Is_Valued_Procedure (Parent_Subp));
15504 Set_Has_Controlling_Result
15505 (New_Subp, Has_Controlling_Result (Parent_Subp));
15508 -- No_Return must be inherited properly. If this is overridden in the
15509 -- case of a dispatching operation, then a check is made in Sem_Disp
15510 -- that the overriding operation is also No_Return (no such check is
15511 -- required for the case of non-dispatching operation.
15513 Set_No_Return (New_Subp, No_Return (Parent_Subp));
15515 -- A derived function with a controlling result is abstract. If the
15516 -- Derived_Type is a nonabstract formal generic derived type, then
15517 -- inherited operations are not abstract: the required check is done at
15518 -- instantiation time. If the derivation is for a generic actual, the
15519 -- function is not abstract unless the actual is.
15521 if Is_Generic_Type (Derived_Type)
15522 and then not Is_Abstract_Type (Derived_Type)
15526 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
15527 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
15529 -- A subprogram subject to pragma Extensions_Visible with value False
15530 -- requires overriding if the subprogram has at least one controlling
15531 -- OUT parameter (SPARK RM 6.1.7(6)).
15533 elsif Ada_Version >= Ada_2005
15534 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15535 or else (Is_Tagged_Type (Derived_Type)
15536 and then Etype (New_Subp) = Derived_Type
15537 and then not Is_Null_Extension (Derived_Type))
15538 or else (Is_Tagged_Type (Derived_Type)
15539 and then Ekind (Etype (New_Subp)) =
15540 E_Anonymous_Access_Type
15541 and then Designated_Type (Etype (New_Subp)) =
15543 and then not Is_Null_Extension (Derived_Type))
15544 or else (Comes_From_Source (Alias (New_Subp))
15545 and then Is_EVF_Procedure (Alias (New_Subp))))
15546 and then No (Actual_Subp)
15548 if not Is_Tagged_Type (Derived_Type)
15549 or else Is_Abstract_Type (Derived_Type)
15550 or else Is_Abstract_Subprogram (Alias (New_Subp))
15552 Set_Is_Abstract_Subprogram (New_Subp);
15554 Set_Requires_Overriding (New_Subp);
15557 elsif Ada_Version < Ada_2005
15558 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15559 or else (Is_Tagged_Type (Derived_Type)
15560 and then Etype (New_Subp) = Derived_Type
15561 and then No (Actual_Subp)))
15563 Set_Is_Abstract_Subprogram (New_Subp);
15565 -- AI05-0097 : an inherited operation that dispatches on result is
15566 -- abstract if the derived type is abstract, even if the parent type
15567 -- is concrete and the derived type is a null extension.
15569 elsif Has_Controlling_Result (Alias (New_Subp))
15570 and then Is_Abstract_Type (Etype (New_Subp))
15572 Set_Is_Abstract_Subprogram (New_Subp);
15574 -- Finally, if the parent type is abstract we must verify that all
15575 -- inherited operations are either non-abstract or overridden, or that
15576 -- the derived type itself is abstract (this check is performed at the
15577 -- end of a package declaration, in Check_Abstract_Overriding). A
15578 -- private overriding in the parent type will not be visible in the
15579 -- derivation if we are not in an inner package or in a child unit of
15580 -- the parent type, in which case the abstractness of the inherited
15581 -- operation is carried to the new subprogram.
15583 elsif Is_Abstract_Type (Parent_Type)
15584 and then not In_Open_Scopes (Scope (Parent_Type))
15585 and then Is_Private_Overriding
15586 and then Is_Abstract_Subprogram (Visible_Subp)
15588 if No (Actual_Subp) then
15589 Set_Alias (New_Subp, Visible_Subp);
15590 Set_Is_Abstract_Subprogram (New_Subp, True);
15593 -- If this is a derivation for an instance of a formal derived
15594 -- type, abstractness comes from the primitive operation of the
15595 -- actual, not from the operation inherited from the ancestor.
15597 Set_Is_Abstract_Subprogram
15598 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
15602 New_Overloaded_Entity (New_Subp, Derived_Type);
15604 -- Ada RM 6.1.1 (15): If a subprogram inherits nonconforming class-wide
15605 -- preconditions and the derived type is abstract, the derived operation
15606 -- is abstract as well if parent subprogram is not abstract or null.
15608 if Is_Abstract_Type (Derived_Type)
15609 and then Has_Non_Trivial_Precondition (Parent_Subp)
15610 and then Present (Interfaces (Derived_Type))
15613 -- Add useful attributes of subprogram before the freeze point,
15614 -- in case freezing is delayed or there are previous errors.
15616 Set_Is_Dispatching_Operation (New_Subp);
15619 Iface_Prim : constant Entity_Id := Covered_Interface_Op (New_Subp);
15622 if Present (Iface_Prim)
15623 and then Has_Non_Trivial_Precondition (Iface_Prim)
15625 Set_Is_Abstract_Subprogram (New_Subp);
15630 -- Check for case of a derived subprogram for the instantiation of a
15631 -- formal derived tagged type, if so mark the subprogram as dispatching
15632 -- and inherit the dispatching attributes of the actual subprogram. The
15633 -- derived subprogram is effectively renaming of the actual subprogram,
15634 -- so it needs to have the same attributes as the actual.
15636 if Present (Actual_Subp)
15637 and then Is_Dispatching_Operation (Actual_Subp)
15639 Set_Is_Dispatching_Operation (New_Subp);
15641 if Present (DTC_Entity (Actual_Subp)) then
15642 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
15643 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
15647 -- Indicate that a derived subprogram does not require a body and that
15648 -- it does not require processing of default expressions.
15650 Set_Has_Completion (New_Subp);
15651 Set_Default_Expressions_Processed (New_Subp);
15653 if Ekind (New_Subp) = E_Function then
15654 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
15656 end Derive_Subprogram;
15658 ------------------------
15659 -- Derive_Subprograms --
15660 ------------------------
15662 procedure Derive_Subprograms
15663 (Parent_Type : Entity_Id;
15664 Derived_Type : Entity_Id;
15665 Generic_Actual : Entity_Id := Empty)
15667 Op_List : constant Elist_Id :=
15668 Collect_Primitive_Operations (Parent_Type);
15670 function Check_Derived_Type return Boolean;
15671 -- Check that all the entities derived from Parent_Type are found in
15672 -- the list of primitives of Derived_Type exactly in the same order.
15674 procedure Derive_Interface_Subprogram
15675 (New_Subp : out Entity_Id;
15677 Actual_Subp : Entity_Id);
15678 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
15679 -- (which is an interface primitive). If Generic_Actual is present then
15680 -- Actual_Subp is the actual subprogram corresponding with the generic
15681 -- subprogram Subp.
15683 ------------------------
15684 -- Check_Derived_Type --
15685 ------------------------
15687 function Check_Derived_Type return Boolean is
15691 New_Subp : Entity_Id;
15696 -- Traverse list of entities in the current scope searching for
15697 -- an incomplete type whose full-view is derived type.
15699 E := First_Entity (Scope (Derived_Type));
15700 while Present (E) and then E /= Derived_Type loop
15701 if Ekind (E) = E_Incomplete_Type
15702 and then Present (Full_View (E))
15703 and then Full_View (E) = Derived_Type
15705 -- Disable this test if Derived_Type completes an incomplete
15706 -- type because in such case more primitives can be added
15707 -- later to the list of primitives of Derived_Type by routine
15708 -- Process_Incomplete_Dependents
15713 E := Next_Entity (E);
15716 List := Collect_Primitive_Operations (Derived_Type);
15717 Elmt := First_Elmt (List);
15719 Op_Elmt := First_Elmt (Op_List);
15720 while Present (Op_Elmt) loop
15721 Subp := Node (Op_Elmt);
15722 New_Subp := Node (Elmt);
15724 -- At this early stage Derived_Type has no entities with attribute
15725 -- Interface_Alias. In addition, such primitives are always
15726 -- located at the end of the list of primitives of Parent_Type.
15727 -- Therefore, if found we can safely stop processing pending
15730 exit when Present (Interface_Alias (Subp));
15732 -- Handle hidden entities
15734 if not Is_Predefined_Dispatching_Operation (Subp)
15735 and then Is_Hidden (Subp)
15737 if Present (New_Subp)
15738 and then Primitive_Names_Match (Subp, New_Subp)
15744 if not Present (New_Subp)
15745 or else Ekind (Subp) /= Ekind (New_Subp)
15746 or else not Primitive_Names_Match (Subp, New_Subp)
15754 Next_Elmt (Op_Elmt);
15758 end Check_Derived_Type;
15760 ---------------------------------
15761 -- Derive_Interface_Subprogram --
15762 ---------------------------------
15764 procedure Derive_Interface_Subprogram
15765 (New_Subp : out Entity_Id;
15767 Actual_Subp : Entity_Id)
15769 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15770 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15773 pragma Assert (Is_Interface (Iface_Type));
15776 (New_Subp => New_Subp,
15777 Parent_Subp => Iface_Subp,
15778 Derived_Type => Derived_Type,
15779 Parent_Type => Iface_Type,
15780 Actual_Subp => Actual_Subp);
15782 -- Given that this new interface entity corresponds with a primitive
15783 -- of the parent that was not overridden we must leave it associated
15784 -- with its parent primitive to ensure that it will share the same
15785 -- dispatch table slot when overridden. We must set the Alias to Subp
15786 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15787 -- (in case we inherited Subp from Iface_Type via a nonabstract
15788 -- generic formal type).
15790 if No (Actual_Subp) then
15791 Set_Alias (New_Subp, Subp);
15794 T : Entity_Id := Find_Dispatching_Type (Subp);
15796 while Etype (T) /= T loop
15797 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15798 Set_Is_Abstract_Subprogram (New_Subp, False);
15806 -- For instantiations this is not needed since the previous call to
15807 -- Derive_Subprogram leaves the entity well decorated.
15810 pragma Assert (Alias (New_Subp) = Actual_Subp);
15813 end Derive_Interface_Subprogram;
15817 Alias_Subp : Entity_Id;
15818 Act_List : Elist_Id;
15819 Act_Elmt : Elmt_Id;
15820 Act_Subp : Entity_Id := Empty;
15822 Need_Search : Boolean := False;
15823 New_Subp : Entity_Id := Empty;
15824 Parent_Base : Entity_Id;
15827 -- Start of processing for Derive_Subprograms
15830 if Ekind (Parent_Type) = E_Record_Type_With_Private
15831 and then Has_Discriminants (Parent_Type)
15832 and then Present (Full_View (Parent_Type))
15834 Parent_Base := Full_View (Parent_Type);
15836 Parent_Base := Parent_Type;
15839 if Present (Generic_Actual) then
15840 Act_List := Collect_Primitive_Operations (Generic_Actual);
15841 Act_Elmt := First_Elmt (Act_List);
15843 Act_List := No_Elist;
15844 Act_Elmt := No_Elmt;
15847 -- Derive primitives inherited from the parent. Note that if the generic
15848 -- actual is present, this is not really a type derivation, it is a
15849 -- completion within an instance.
15851 -- Case 1: Derived_Type does not implement interfaces
15853 if not Is_Tagged_Type (Derived_Type)
15854 or else (not Has_Interfaces (Derived_Type)
15855 and then not (Present (Generic_Actual)
15856 and then Has_Interfaces (Generic_Actual)))
15858 Elmt := First_Elmt (Op_List);
15859 while Present (Elmt) loop
15860 Subp := Node (Elmt);
15862 -- Literals are derived earlier in the process of building the
15863 -- derived type, and are skipped here.
15865 if Ekind (Subp) = E_Enumeration_Literal then
15868 -- The actual is a direct descendant and the common primitive
15869 -- operations appear in the same order.
15871 -- If the generic parent type is present, the derived type is an
15872 -- instance of a formal derived type, and within the instance its
15873 -- operations are those of the actual. We derive from the formal
15874 -- type but make the inherited operations aliases of the
15875 -- corresponding operations of the actual.
15878 pragma Assert (No (Node (Act_Elmt))
15879 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15882 (Subp, Node (Act_Elmt),
15883 Skip_Controlling_Formals => True)));
15886 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15888 if Present (Act_Elmt) then
15889 Next_Elmt (Act_Elmt);
15896 -- Case 2: Derived_Type implements interfaces
15899 -- If the parent type has no predefined primitives we remove
15900 -- predefined primitives from the list of primitives of generic
15901 -- actual to simplify the complexity of this algorithm.
15903 if Present (Generic_Actual) then
15905 Has_Predefined_Primitives : Boolean := False;
15908 -- Check if the parent type has predefined primitives
15910 Elmt := First_Elmt (Op_List);
15911 while Present (Elmt) loop
15912 Subp := Node (Elmt);
15914 if Is_Predefined_Dispatching_Operation (Subp)
15915 and then not Comes_From_Source (Ultimate_Alias (Subp))
15917 Has_Predefined_Primitives := True;
15924 -- Remove predefined primitives of Generic_Actual. We must use
15925 -- an auxiliary list because in case of tagged types the value
15926 -- returned by Collect_Primitive_Operations is the value stored
15927 -- in its Primitive_Operations attribute (and we don't want to
15928 -- modify its current contents).
15930 if not Has_Predefined_Primitives then
15932 Aux_List : constant Elist_Id := New_Elmt_List;
15935 Elmt := First_Elmt (Act_List);
15936 while Present (Elmt) loop
15937 Subp := Node (Elmt);
15939 if not Is_Predefined_Dispatching_Operation (Subp)
15940 or else Comes_From_Source (Subp)
15942 Append_Elmt (Subp, Aux_List);
15948 Act_List := Aux_List;
15952 Act_Elmt := First_Elmt (Act_List);
15953 Act_Subp := Node (Act_Elmt);
15957 -- Stage 1: If the generic actual is not present we derive the
15958 -- primitives inherited from the parent type. If the generic parent
15959 -- type is present, the derived type is an instance of a formal
15960 -- derived type, and within the instance its operations are those of
15961 -- the actual. We derive from the formal type but make the inherited
15962 -- operations aliases of the corresponding operations of the actual.
15964 Elmt := First_Elmt (Op_List);
15965 while Present (Elmt) loop
15966 Subp := Node (Elmt);
15967 Alias_Subp := Ultimate_Alias (Subp);
15969 -- Do not derive internal entities of the parent that link
15970 -- interface primitives with their covering primitive. These
15971 -- entities will be added to this type when frozen.
15973 if Present (Interface_Alias (Subp)) then
15977 -- If the generic actual is present find the corresponding
15978 -- operation in the generic actual. If the parent type is a
15979 -- direct ancestor of the derived type then, even if it is an
15980 -- interface, the operations are inherited from the primary
15981 -- dispatch table and are in the proper order. If we detect here
15982 -- that primitives are not in the same order we traverse the list
15983 -- of primitive operations of the actual to find the one that
15984 -- implements the interface primitive.
15988 (Present (Generic_Actual)
15989 and then Present (Act_Subp)
15991 (Primitive_Names_Match (Subp, Act_Subp)
15993 Type_Conformant (Subp, Act_Subp,
15994 Skip_Controlling_Formals => True)))
15996 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15997 Use_Full_View => True));
15999 -- Remember that we need searching for all pending primitives
16001 Need_Search := True;
16003 -- Handle entities associated with interface primitives
16005 if Present (Alias_Subp)
16006 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
16007 and then not Is_Predefined_Dispatching_Operation (Subp)
16009 -- Search for the primitive in the homonym chain
16012 Find_Primitive_Covering_Interface
16013 (Tagged_Type => Generic_Actual,
16014 Iface_Prim => Alias_Subp);
16016 -- Previous search may not locate primitives covering
16017 -- interfaces defined in generics units or instantiations.
16018 -- (it fails if the covering primitive has formals whose
16019 -- type is also defined in generics or instantiations).
16020 -- In such case we search in the list of primitives of the
16021 -- generic actual for the internal entity that links the
16022 -- interface primitive and the covering primitive.
16025 and then Is_Generic_Type (Parent_Type)
16027 -- This code has been designed to handle only generic
16028 -- formals that implement interfaces that are defined
16029 -- in a generic unit or instantiation. If this code is
16030 -- needed for other cases we must review it because
16031 -- (given that it relies on Original_Location to locate
16032 -- the primitive of Generic_Actual that covers the
16033 -- interface) it could leave linked through attribute
16034 -- Alias entities of unrelated instantiations).
16038 (Scope (Find_Dispatching_Type (Alias_Subp)))
16040 Instantiation_Depth
16041 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
16044 Iface_Prim_Loc : constant Source_Ptr :=
16045 Original_Location (Sloc (Alias_Subp));
16052 First_Elmt (Primitive_Operations (Generic_Actual));
16054 Search : while Present (Elmt) loop
16055 Prim := Node (Elmt);
16057 if Present (Interface_Alias (Prim))
16058 and then Original_Location
16059 (Sloc (Interface_Alias (Prim))) =
16062 Act_Subp := Alias (Prim);
16071 pragma Assert (Present (Act_Subp)
16072 or else Is_Abstract_Type (Generic_Actual)
16073 or else Serious_Errors_Detected > 0);
16075 -- Handle predefined primitives plus the rest of user-defined
16079 Act_Elmt := First_Elmt (Act_List);
16080 while Present (Act_Elmt) loop
16081 Act_Subp := Node (Act_Elmt);
16083 exit when Primitive_Names_Match (Subp, Act_Subp)
16084 and then Type_Conformant
16086 Skip_Controlling_Formals => True)
16087 and then No (Interface_Alias (Act_Subp));
16089 Next_Elmt (Act_Elmt);
16092 if No (Act_Elmt) then
16098 -- Case 1: If the parent is a limited interface then it has the
16099 -- predefined primitives of synchronized interfaces. However, the
16100 -- actual type may be a non-limited type and hence it does not
16101 -- have such primitives.
16103 if Present (Generic_Actual)
16104 and then not Present (Act_Subp)
16105 and then Is_Limited_Interface (Parent_Base)
16106 and then Is_Predefined_Interface_Primitive (Subp)
16110 -- Case 2: Inherit entities associated with interfaces that were
16111 -- not covered by the parent type. We exclude here null interface
16112 -- primitives because they do not need special management.
16114 -- We also exclude interface operations that are renamings. If the
16115 -- subprogram is an explicit renaming of an interface primitive,
16116 -- it is a regular primitive operation, and the presence of its
16117 -- alias is not relevant: it has to be derived like any other
16120 elsif Present (Alias (Subp))
16121 and then Nkind (Unit_Declaration_Node (Subp)) /=
16122 N_Subprogram_Renaming_Declaration
16123 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
16125 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
16126 and then Null_Present (Parent (Alias_Subp)))
16128 -- If this is an abstract private type then we transfer the
16129 -- derivation of the interface primitive from the partial view
16130 -- to the full view. This is safe because all the interfaces
16131 -- must be visible in the partial view. Done to avoid adding
16132 -- a new interface derivation to the private part of the
16133 -- enclosing package; otherwise this new derivation would be
16134 -- decorated as hidden when the analysis of the enclosing
16135 -- package completes.
16137 if Is_Abstract_Type (Derived_Type)
16138 and then In_Private_Part (Current_Scope)
16139 and then Has_Private_Declaration (Derived_Type)
16142 Partial_View : Entity_Id;
16147 Partial_View := First_Entity (Current_Scope);
16149 exit when No (Partial_View)
16150 or else (Has_Private_Declaration (Partial_View)
16152 Full_View (Partial_View) = Derived_Type);
16154 Next_Entity (Partial_View);
16157 -- If the partial view was not found then the source code
16158 -- has errors and the derivation is not needed.
16160 if Present (Partial_View) then
16162 First_Elmt (Primitive_Operations (Partial_View));
16163 while Present (Elmt) loop
16164 Ent := Node (Elmt);
16166 if Present (Alias (Ent))
16167 and then Ultimate_Alias (Ent) = Alias (Subp)
16170 (Ent, Primitive_Operations (Derived_Type));
16177 -- If the interface primitive was not found in the
16178 -- partial view then this interface primitive was
16179 -- overridden. We add a derivation to activate in
16180 -- Derive_Progenitor_Subprograms the machinery to
16184 Derive_Interface_Subprogram
16185 (New_Subp => New_Subp,
16187 Actual_Subp => Act_Subp);
16192 Derive_Interface_Subprogram
16193 (New_Subp => New_Subp,
16195 Actual_Subp => Act_Subp);
16198 -- Case 3: Common derivation
16202 (New_Subp => New_Subp,
16203 Parent_Subp => Subp,
16204 Derived_Type => Derived_Type,
16205 Parent_Type => Parent_Base,
16206 Actual_Subp => Act_Subp);
16209 -- No need to update Act_Elm if we must search for the
16210 -- corresponding operation in the generic actual
16213 and then Present (Act_Elmt)
16215 Next_Elmt (Act_Elmt);
16216 Act_Subp := Node (Act_Elmt);
16223 -- Inherit additional operations from progenitors. If the derived
16224 -- type is a generic actual, there are not new primitive operations
16225 -- for the type because it has those of the actual, and therefore
16226 -- nothing needs to be done. The renamings generated above are not
16227 -- primitive operations, and their purpose is simply to make the
16228 -- proper operations visible within an instantiation.
16230 if No (Generic_Actual) then
16231 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
16235 -- Final check: Direct descendants must have their primitives in the
16236 -- same order. We exclude from this test untagged types and instances
16237 -- of formal derived types. We skip this test if we have already
16238 -- reported serious errors in the sources.
16240 pragma Assert (not Is_Tagged_Type (Derived_Type)
16241 or else Present (Generic_Actual)
16242 or else Serious_Errors_Detected > 0
16243 or else Check_Derived_Type);
16244 end Derive_Subprograms;
16246 --------------------------------
16247 -- Derived_Standard_Character --
16248 --------------------------------
16250 procedure Derived_Standard_Character
16252 Parent_Type : Entity_Id;
16253 Derived_Type : Entity_Id)
16255 Loc : constant Source_Ptr := Sloc (N);
16256 Def : constant Node_Id := Type_Definition (N);
16257 Indic : constant Node_Id := Subtype_Indication (Def);
16258 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
16259 Implicit_Base : constant Entity_Id :=
16261 (E_Enumeration_Type, N, Derived_Type, 'B');
16267 Discard_Node (Process_Subtype (Indic, N));
16269 Set_Etype (Implicit_Base, Parent_Base);
16270 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
16271 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
16273 Set_Is_Character_Type (Implicit_Base, True);
16274 Set_Has_Delayed_Freeze (Implicit_Base);
16276 -- The bounds of the implicit base are the bounds of the parent base.
16277 -- Note that their type is the parent base.
16279 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
16280 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
16282 Set_Scalar_Range (Implicit_Base,
16285 High_Bound => Hi));
16287 Conditional_Delay (Derived_Type, Parent_Type);
16289 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
16290 Set_Etype (Derived_Type, Implicit_Base);
16291 Set_Size_Info (Derived_Type, Parent_Type);
16293 if Unknown_RM_Size (Derived_Type) then
16294 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
16297 Set_Is_Character_Type (Derived_Type, True);
16299 if Nkind (Indic) /= N_Subtype_Indication then
16301 -- If no explicit constraint, the bounds are those
16302 -- of the parent type.
16304 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
16305 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
16306 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
16309 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
16311 -- Because the implicit base is used in the conversion of the bounds, we
16312 -- have to freeze it now. This is similar to what is done for numeric
16313 -- types, and it equally suspicious, but otherwise a non-static bound
16314 -- will have a reference to an unfrozen type, which is rejected by Gigi
16315 -- (???). This requires specific care for definition of stream
16316 -- attributes. For details, see comments at the end of
16317 -- Build_Derived_Numeric_Type.
16319 Freeze_Before (N, Implicit_Base);
16320 end Derived_Standard_Character;
16322 ------------------------------
16323 -- Derived_Type_Declaration --
16324 ------------------------------
16326 procedure Derived_Type_Declaration
16329 Is_Completion : Boolean)
16331 Parent_Type : Entity_Id;
16333 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
16334 -- Check whether the parent type is a generic formal, or derives
16335 -- directly or indirectly from one.
16337 ------------------------
16338 -- Comes_From_Generic --
16339 ------------------------
16341 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
16343 if Is_Generic_Type (Typ) then
16346 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
16349 elsif Is_Private_Type (Typ)
16350 and then Present (Full_View (Typ))
16351 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
16355 elsif Is_Generic_Actual_Type (Typ) then
16361 end Comes_From_Generic;
16365 Def : constant Node_Id := Type_Definition (N);
16366 Iface_Def : Node_Id;
16367 Indic : constant Node_Id := Subtype_Indication (Def);
16368 Extension : constant Node_Id := Record_Extension_Part (Def);
16369 Parent_Node : Node_Id;
16372 -- Start of processing for Derived_Type_Declaration
16375 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
16378 and then Is_Tagged_Type (Parent_Type)
16381 Partial_View : constant Entity_Id :=
16382 Incomplete_Or_Partial_View (Parent_Type);
16385 -- If the partial view was not found then the parent type is not
16386 -- a private type. Otherwise check if the partial view is a tagged
16389 if Present (Partial_View)
16390 and then Is_Private_Type (Partial_View)
16391 and then not Is_Tagged_Type (Partial_View)
16394 ("cannot derive from & declared as untagged private "
16395 & "(SPARK RM 3.4(1))", N, Partial_View);
16400 -- Ada 2005 (AI-251): In case of interface derivation check that the
16401 -- parent is also an interface.
16403 if Interface_Present (Def) then
16404 Check_SPARK_05_Restriction ("interface is not allowed", Def);
16406 if not Is_Interface (Parent_Type) then
16407 Diagnose_Interface (Indic, Parent_Type);
16410 Parent_Node := Parent (Base_Type (Parent_Type));
16411 Iface_Def := Type_Definition (Parent_Node);
16413 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
16414 -- other limited interfaces.
16416 if Limited_Present (Def) then
16417 if Limited_Present (Iface_Def) then
16420 elsif Protected_Present (Iface_Def) then
16422 ("descendant of & must be declared as a protected "
16423 & "interface", N, Parent_Type);
16425 elsif Synchronized_Present (Iface_Def) then
16427 ("descendant of & must be declared as a synchronized "
16428 & "interface", N, Parent_Type);
16430 elsif Task_Present (Iface_Def) then
16432 ("descendant of & must be declared as a task interface",
16437 ("(Ada 2005) limited interface cannot inherit from "
16438 & "non-limited interface", Indic);
16441 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
16442 -- from non-limited or limited interfaces.
16444 elsif not Protected_Present (Def)
16445 and then not Synchronized_Present (Def)
16446 and then not Task_Present (Def)
16448 if Limited_Present (Iface_Def) then
16451 elsif Protected_Present (Iface_Def) then
16453 ("descendant of & must be declared as a protected "
16454 & "interface", N, Parent_Type);
16456 elsif Synchronized_Present (Iface_Def) then
16458 ("descendant of & must be declared as a synchronized "
16459 & "interface", N, Parent_Type);
16461 elsif Task_Present (Iface_Def) then
16463 ("descendant of & must be declared as a task interface",
16472 if Is_Tagged_Type (Parent_Type)
16473 and then Is_Concurrent_Type (Parent_Type)
16474 and then not Is_Interface (Parent_Type)
16477 ("parent type of a record extension cannot be a synchronized "
16478 & "tagged type (RM 3.9.1 (3/1))", N);
16479 Set_Etype (T, Any_Type);
16483 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
16486 if Is_Tagged_Type (Parent_Type)
16487 and then Is_Non_Empty_List (Interface_List (Def))
16494 Intf := First (Interface_List (Def));
16495 while Present (Intf) loop
16496 T := Find_Type_Of_Subtype_Indic (Intf);
16498 if not Is_Interface (T) then
16499 Diagnose_Interface (Intf, T);
16501 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
16502 -- a limited type from having a nonlimited progenitor.
16504 elsif (Limited_Present (Def)
16505 or else (not Is_Interface (Parent_Type)
16506 and then Is_Limited_Type (Parent_Type)))
16507 and then not Is_Limited_Interface (T)
16510 ("progenitor interface& of limited type must be limited",
16519 if Parent_Type = Any_Type
16520 or else Etype (Parent_Type) = Any_Type
16521 or else (Is_Class_Wide_Type (Parent_Type)
16522 and then Etype (Parent_Type) = T)
16524 -- If Parent_Type is undefined or illegal, make new type into a
16525 -- subtype of Any_Type, and set a few attributes to prevent cascaded
16526 -- errors. If this is a self-definition, emit error now.
16528 if T = Parent_Type or else T = Etype (Parent_Type) then
16529 Error_Msg_N ("type cannot be used in its own definition", Indic);
16532 Set_Ekind (T, Ekind (Parent_Type));
16533 Set_Etype (T, Any_Type);
16534 Set_Scalar_Range (T, Scalar_Range (Any_Type));
16536 if Is_Tagged_Type (T)
16537 and then Is_Record_Type (T)
16539 Set_Direct_Primitive_Operations (T, New_Elmt_List);
16545 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
16546 -- an interface is special because the list of interfaces in the full
16547 -- view can be given in any order. For example:
16549 -- type A is interface;
16550 -- type B is interface and A;
16551 -- type D is new B with private;
16553 -- type D is new A and B with null record; -- 1 --
16555 -- In this case we perform the following transformation of -1-:
16557 -- type D is new B and A with null record;
16559 -- If the parent of the full-view covers the parent of the partial-view
16560 -- we have two possible cases:
16562 -- 1) They have the same parent
16563 -- 2) The parent of the full-view implements some further interfaces
16565 -- In both cases we do not need to perform the transformation. In the
16566 -- first case the source program is correct and the transformation is
16567 -- not needed; in the second case the source program does not fulfill
16568 -- the no-hidden interfaces rule (AI-396) and the error will be reported
16571 -- This transformation not only simplifies the rest of the analysis of
16572 -- this type declaration but also simplifies the correct generation of
16573 -- the object layout to the expander.
16575 if In_Private_Part (Current_Scope)
16576 and then Is_Interface (Parent_Type)
16580 Partial_View : Entity_Id;
16581 Partial_View_Parent : Entity_Id;
16582 New_Iface : Node_Id;
16585 -- Look for the associated private type declaration
16587 Partial_View := Incomplete_Or_Partial_View (T);
16589 -- If the partial view was not found then the source code has
16590 -- errors and the transformation is not needed.
16592 if Present (Partial_View) then
16593 Partial_View_Parent := Etype (Partial_View);
16595 -- If the parent of the full-view covers the parent of the
16596 -- partial-view we have nothing else to do.
16598 if Interface_Present_In_Ancestor
16599 (Parent_Type, Partial_View_Parent)
16603 -- Traverse the list of interfaces of the full-view to look
16604 -- for the parent of the partial-view and perform the tree
16608 Iface := First (Interface_List (Def));
16609 while Present (Iface) loop
16610 if Etype (Iface) = Etype (Partial_View) then
16611 Rewrite (Subtype_Indication (Def),
16612 New_Copy (Subtype_Indication
16613 (Parent (Partial_View))));
16616 Make_Identifier (Sloc (N), Chars (Parent_Type));
16617 Append (New_Iface, Interface_List (Def));
16619 -- Analyze the transformed code
16621 Derived_Type_Declaration (T, N, Is_Completion);
16632 -- Only composite types other than array types are allowed to have
16635 if Present (Discriminant_Specifications (N)) then
16636 if (Is_Elementary_Type (Parent_Type)
16638 Is_Array_Type (Parent_Type))
16639 and then not Error_Posted (N)
16642 ("elementary or array type cannot have discriminants",
16643 Defining_Identifier (First (Discriminant_Specifications (N))));
16644 Set_Has_Discriminants (T, False);
16646 -- The type is allowed to have discriminants
16649 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
16653 -- In Ada 83, a derived type defined in a package specification cannot
16654 -- be used for further derivation until the end of its visible part.
16655 -- Note that derivation in the private part of the package is allowed.
16657 if Ada_Version = Ada_83
16658 and then Is_Derived_Type (Parent_Type)
16659 and then In_Visible_Part (Scope (Parent_Type))
16661 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
16663 ("(Ada 83): premature use of type for derivation", Indic);
16667 -- Check for early use of incomplete or private type
16669 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
16670 Error_Msg_N ("premature derivation of incomplete type", Indic);
16673 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
16674 and then not Comes_From_Generic (Parent_Type))
16675 or else Has_Private_Component (Parent_Type)
16677 -- The ancestor type of a formal type can be incomplete, in which
16678 -- case only the operations of the partial view are available in the
16679 -- generic. Subsequent checks may be required when the full view is
16680 -- analyzed to verify that a derivation from a tagged type has an
16683 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
16686 elsif No (Underlying_Type (Parent_Type))
16687 or else Has_Private_Component (Parent_Type)
16690 ("premature derivation of derived or private type", Indic);
16692 -- Flag the type itself as being in error, this prevents some
16693 -- nasty problems with subsequent uses of the malformed type.
16695 Set_Error_Posted (T);
16697 -- Check that within the immediate scope of an untagged partial
16698 -- view it's illegal to derive from the partial view if the
16699 -- full view is tagged. (7.3(7))
16701 -- We verify that the Parent_Type is a partial view by checking
16702 -- that it is not a Full_Type_Declaration (i.e. a private type or
16703 -- private extension declaration), to distinguish a partial view
16704 -- from a derivation from a private type which also appears as
16705 -- E_Private_Type. If the parent base type is not declared in an
16706 -- enclosing scope there is no need to check.
16708 elsif Present (Full_View (Parent_Type))
16709 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
16710 and then not Is_Tagged_Type (Parent_Type)
16711 and then Is_Tagged_Type (Full_View (Parent_Type))
16712 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
16715 ("premature derivation from type with tagged full view",
16720 -- Check that form of derivation is appropriate
16722 Taggd := Is_Tagged_Type (Parent_Type);
16724 -- Set the parent type to the class-wide type's specific type in this
16725 -- case to prevent cascading errors
16727 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16728 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16729 Set_Etype (T, Etype (Parent_Type));
16733 if Present (Extension) and then not Taggd then
16735 ("type derived from untagged type cannot have extension", Indic);
16737 elsif No (Extension) and then Taggd then
16739 -- If this declaration is within a private part (or body) of a
16740 -- generic instantiation then the derivation is allowed (the parent
16741 -- type can only appear tagged in this case if it's a generic actual
16742 -- type, since it would otherwise have been rejected in the analysis
16743 -- of the generic template).
16745 if not Is_Generic_Actual_Type (Parent_Type)
16746 or else In_Visible_Part (Scope (Parent_Type))
16748 if Is_Class_Wide_Type (Parent_Type) then
16750 ("parent type must not be a class-wide type", Indic);
16752 -- Use specific type to prevent cascaded errors.
16754 Parent_Type := Etype (Parent_Type);
16758 ("type derived from tagged type must have extension", Indic);
16763 -- AI-443: Synchronized formal derived types require a private
16764 -- extension. There is no point in checking the ancestor type or
16765 -- the progenitors since the construct is wrong to begin with.
16767 if Ada_Version >= Ada_2005
16768 and then Is_Generic_Type (T)
16769 and then Present (Original_Node (N))
16772 Decl : constant Node_Id := Original_Node (N);
16775 if Nkind (Decl) = N_Formal_Type_Declaration
16776 and then Nkind (Formal_Type_Definition (Decl)) =
16777 N_Formal_Derived_Type_Definition
16778 and then Synchronized_Present (Formal_Type_Definition (Decl))
16779 and then No (Extension)
16781 -- Avoid emitting a duplicate error message
16783 and then not Error_Posted (Indic)
16786 ("synchronized derived type must have extension", N);
16791 if Null_Exclusion_Present (Def)
16792 and then not Is_Access_Type (Parent_Type)
16794 Error_Msg_N ("null exclusion can only apply to an access type", N);
16797 -- Avoid deriving parent primitives of underlying record views
16799 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16800 Derive_Subps => not Is_Underlying_Record_View (T));
16802 -- AI-419: The parent type of an explicitly limited derived type must
16803 -- be a limited type or a limited interface.
16805 if Limited_Present (Def) then
16806 Set_Is_Limited_Record (T);
16808 if Is_Interface (T) then
16809 Set_Is_Limited_Interface (T);
16812 if not Is_Limited_Type (Parent_Type)
16814 (not Is_Interface (Parent_Type)
16815 or else not Is_Limited_Interface (Parent_Type))
16817 -- AI05-0096: a derivation in the private part of an instance is
16818 -- legal if the generic formal is untagged limited, and the actual
16821 if Is_Generic_Actual_Type (Parent_Type)
16822 and then In_Private_Part (Current_Scope)
16825 (Generic_Parent_Type (Parent (Parent_Type)))
16831 ("parent type& of limited type must be limited",
16837 -- In SPARK, there are no derived type definitions other than type
16838 -- extensions of tagged record types.
16840 if No (Extension) then
16841 Check_SPARK_05_Restriction
16842 ("derived type is not allowed", Original_Node (N));
16844 end Derived_Type_Declaration;
16846 ------------------------
16847 -- Diagnose_Interface --
16848 ------------------------
16850 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16852 if not Is_Interface (E) and then E /= Any_Type then
16853 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16855 end Diagnose_Interface;
16857 ----------------------------------
16858 -- Enumeration_Type_Declaration --
16859 ----------------------------------
16861 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16868 -- Create identifier node representing lower bound
16870 B_Node := New_Node (N_Identifier, Sloc (Def));
16871 L := First (Literals (Def));
16872 Set_Chars (B_Node, Chars (L));
16873 Set_Entity (B_Node, L);
16874 Set_Etype (B_Node, T);
16875 Set_Is_Static_Expression (B_Node, True);
16877 R_Node := New_Node (N_Range, Sloc (Def));
16878 Set_Low_Bound (R_Node, B_Node);
16880 Set_Ekind (T, E_Enumeration_Type);
16881 Set_First_Literal (T, L);
16883 Set_Is_Constrained (T);
16887 -- Loop through literals of enumeration type setting pos and rep values
16888 -- except that if the Ekind is already set, then it means the literal
16889 -- was already constructed (case of a derived type declaration and we
16890 -- should not disturb the Pos and Rep values.
16892 while Present (L) loop
16893 if Ekind (L) /= E_Enumeration_Literal then
16894 Set_Ekind (L, E_Enumeration_Literal);
16895 Set_Enumeration_Pos (L, Ev);
16896 Set_Enumeration_Rep (L, Ev);
16897 Set_Is_Known_Valid (L, True);
16901 New_Overloaded_Entity (L);
16902 Generate_Definition (L);
16903 Set_Convention (L, Convention_Intrinsic);
16905 -- Case of character literal
16907 if Nkind (L) = N_Defining_Character_Literal then
16908 Set_Is_Character_Type (T, True);
16910 -- Check violation of No_Wide_Characters
16912 if Restriction_Check_Required (No_Wide_Characters) then
16913 Get_Name_String (Chars (L));
16915 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16916 Check_Restriction (No_Wide_Characters, L);
16925 -- Now create a node representing upper bound
16927 B_Node := New_Node (N_Identifier, Sloc (Def));
16928 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16929 Set_Entity (B_Node, Last (Literals (Def)));
16930 Set_Etype (B_Node, T);
16931 Set_Is_Static_Expression (B_Node, True);
16933 Set_High_Bound (R_Node, B_Node);
16935 -- Initialize various fields of the type. Some of this information
16936 -- may be overwritten later through rep.clauses.
16938 Set_Scalar_Range (T, R_Node);
16939 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16940 Set_Enum_Esize (T);
16941 Set_Enum_Pos_To_Rep (T, Empty);
16943 -- Set Discard_Names if configuration pragma set, or if there is
16944 -- a parameterless pragma in the current declarative region
16946 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16947 Set_Discard_Names (T);
16950 -- Process end label if there is one
16952 if Present (Def) then
16953 Process_End_Label (Def, 'e', T);
16955 end Enumeration_Type_Declaration;
16957 ---------------------------------
16958 -- Expand_To_Stored_Constraint --
16959 ---------------------------------
16961 function Expand_To_Stored_Constraint
16963 Constraint : Elist_Id) return Elist_Id
16965 Explicitly_Discriminated_Type : Entity_Id;
16966 Expansion : Elist_Id;
16967 Discriminant : Entity_Id;
16969 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16970 -- Find the nearest type that actually specifies discriminants
16972 ---------------------------------
16973 -- Type_With_Explicit_Discrims --
16974 ---------------------------------
16976 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16977 Typ : constant E := Base_Type (Id);
16980 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16981 if Present (Full_View (Typ)) then
16982 return Type_With_Explicit_Discrims (Full_View (Typ));
16986 if Has_Discriminants (Typ) then
16991 if Etype (Typ) = Typ then
16993 elsif Has_Discriminants (Typ) then
16996 return Type_With_Explicit_Discrims (Etype (Typ));
16999 end Type_With_Explicit_Discrims;
17001 -- Start of processing for Expand_To_Stored_Constraint
17004 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
17008 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
17010 if No (Explicitly_Discriminated_Type) then
17014 Expansion := New_Elmt_List;
17017 First_Stored_Discriminant (Explicitly_Discriminated_Type);
17018 while Present (Discriminant) loop
17020 (Get_Discriminant_Value
17021 (Discriminant, Explicitly_Discriminated_Type, Constraint),
17023 Next_Stored_Discriminant (Discriminant);
17027 end Expand_To_Stored_Constraint;
17029 ---------------------------
17030 -- Find_Hidden_Interface --
17031 ---------------------------
17033 function Find_Hidden_Interface
17035 Dest : Elist_Id) return Entity_Id
17038 Iface_Elmt : Elmt_Id;
17041 if Present (Src) and then Present (Dest) then
17042 Iface_Elmt := First_Elmt (Src);
17043 while Present (Iface_Elmt) loop
17044 Iface := Node (Iface_Elmt);
17046 if Is_Interface (Iface)
17047 and then not Contain_Interface (Iface, Dest)
17052 Next_Elmt (Iface_Elmt);
17057 end Find_Hidden_Interface;
17059 --------------------
17060 -- Find_Type_Name --
17061 --------------------
17063 function Find_Type_Name (N : Node_Id) return Entity_Id is
17064 Id : constant Entity_Id := Defining_Identifier (N);
17065 New_Id : Entity_Id;
17067 Prev_Par : Node_Id;
17069 procedure Check_Duplicate_Aspects;
17070 -- Check that aspects specified in a completion have not been specified
17071 -- already in the partial view.
17073 procedure Tag_Mismatch;
17074 -- Diagnose a tagged partial view whose full view is untagged. We post
17075 -- the message on the full view, with a reference to the previous
17076 -- partial view. The partial view can be private or incomplete, and
17077 -- these are handled in a different manner, so we determine the position
17078 -- of the error message from the respective slocs of both.
17080 -----------------------------
17081 -- Check_Duplicate_Aspects --
17082 -----------------------------
17084 procedure Check_Duplicate_Aspects is
17085 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id;
17086 -- Return the corresponding aspect of the partial view which matches
17087 -- the aspect id of Asp. Return Empty is no such aspect exists.
17089 -----------------------------
17090 -- Get_Partial_View_Aspect --
17091 -----------------------------
17093 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id is
17094 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp);
17095 Prev_Asps : constant List_Id := Aspect_Specifications (Prev_Par);
17096 Prev_Asp : Node_Id;
17099 if Present (Prev_Asps) then
17100 Prev_Asp := First (Prev_Asps);
17101 while Present (Prev_Asp) loop
17102 if Get_Aspect_Id (Prev_Asp) = Asp_Id then
17111 end Get_Partial_View_Aspect;
17115 Full_Asps : constant List_Id := Aspect_Specifications (N);
17116 Full_Asp : Node_Id;
17117 Part_Asp : Node_Id;
17119 -- Start of processing for Check_Duplicate_Aspects
17122 if Present (Full_Asps) then
17123 Full_Asp := First (Full_Asps);
17124 while Present (Full_Asp) loop
17125 Part_Asp := Get_Partial_View_Aspect (Full_Asp);
17127 -- An aspect and its class-wide counterpart are two distinct
17128 -- aspects and may apply to both views of an entity.
17130 if Present (Part_Asp)
17131 and then Class_Present (Part_Asp) = Class_Present (Full_Asp)
17134 ("aspect already specified in private declaration",
17141 if Has_Discriminants (Prev)
17142 and then not Has_Unknown_Discriminants (Prev)
17143 and then Get_Aspect_Id (Full_Asp) =
17144 Aspect_Implicit_Dereference
17147 ("cannot specify aspect if partial view has known "
17148 & "discriminants", Full_Asp);
17154 end Check_Duplicate_Aspects;
17160 procedure Tag_Mismatch is
17162 if Sloc (Prev) < Sloc (Id) then
17163 if Ada_Version >= Ada_2012
17164 and then Nkind (N) = N_Private_Type_Declaration
17167 ("declaration of private } must be a tagged type ", Id, Prev);
17170 ("full declaration of } must be a tagged type ", Id, Prev);
17174 if Ada_Version >= Ada_2012
17175 and then Nkind (N) = N_Private_Type_Declaration
17178 ("declaration of private } must be a tagged type ", Prev, Id);
17181 ("full declaration of } must be a tagged type ", Prev, Id);
17186 -- Start of processing for Find_Type_Name
17189 -- Find incomplete declaration, if one was given
17191 Prev := Current_Entity_In_Scope (Id);
17193 -- New type declaration
17199 -- Previous declaration exists
17202 Prev_Par := Parent (Prev);
17204 -- Error if not incomplete/private case except if previous
17205 -- declaration is implicit, etc. Enter_Name will emit error if
17208 if not Is_Incomplete_Or_Private_Type (Prev) then
17212 -- Check invalid completion of private or incomplete type
17214 elsif not Nkind_In (N, N_Full_Type_Declaration,
17215 N_Task_Type_Declaration,
17216 N_Protected_Type_Declaration)
17218 (Ada_Version < Ada_2012
17219 or else not Is_Incomplete_Type (Prev)
17220 or else not Nkind_In (N, N_Private_Type_Declaration,
17221 N_Private_Extension_Declaration))
17223 -- Completion must be a full type declarations (RM 7.3(4))
17225 Error_Msg_Sloc := Sloc (Prev);
17226 Error_Msg_NE ("invalid completion of }", Id, Prev);
17228 -- Set scope of Id to avoid cascaded errors. Entity is never
17229 -- examined again, except when saving globals in generics.
17231 Set_Scope (Id, Current_Scope);
17234 -- If this is a repeated incomplete declaration, no further
17235 -- checks are possible.
17237 if Nkind (N) = N_Incomplete_Type_Declaration then
17241 -- Case of full declaration of incomplete type
17243 elsif Ekind (Prev) = E_Incomplete_Type
17244 and then (Ada_Version < Ada_2012
17245 or else No (Full_View (Prev))
17246 or else not Is_Private_Type (Full_View (Prev)))
17248 -- Indicate that the incomplete declaration has a matching full
17249 -- declaration. The defining occurrence of the incomplete
17250 -- declaration remains the visible one, and the procedure
17251 -- Get_Full_View dereferences it whenever the type is used.
17253 if Present (Full_View (Prev)) then
17254 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
17257 Set_Full_View (Prev, Id);
17258 Append_Entity (Id, Current_Scope);
17259 Set_Is_Public (Id, Is_Public (Prev));
17260 Set_Is_Internal (Id);
17263 -- If the incomplete view is tagged, a class_wide type has been
17264 -- created already. Use it for the private type as well, in order
17265 -- to prevent multiple incompatible class-wide types that may be
17266 -- created for self-referential anonymous access components.
17268 if Is_Tagged_Type (Prev)
17269 and then Present (Class_Wide_Type (Prev))
17271 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
17272 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
17274 -- Type of the class-wide type is the current Id. Previously
17275 -- this was not done for private declarations because of order-
17276 -- of-elaboration issues in the back end, but gigi now handles
17279 Set_Etype (Class_Wide_Type (Id), Id);
17282 -- Case of full declaration of private type
17285 -- If the private type was a completion of an incomplete type then
17286 -- update Prev to reference the private type
17288 if Ada_Version >= Ada_2012
17289 and then Ekind (Prev) = E_Incomplete_Type
17290 and then Present (Full_View (Prev))
17291 and then Is_Private_Type (Full_View (Prev))
17293 Prev := Full_View (Prev);
17294 Prev_Par := Parent (Prev);
17297 if Nkind (N) = N_Full_Type_Declaration
17299 (Type_Definition (N), N_Record_Definition,
17300 N_Derived_Type_Definition)
17301 and then Interface_Present (Type_Definition (N))
17304 ("completion of private type cannot be an interface", N);
17307 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
17308 if Etype (Prev) /= Prev then
17310 -- Prev is a private subtype or a derived type, and needs
17313 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
17316 elsif Ekind (Prev) = E_Private_Type
17317 and then Nkind_In (N, N_Task_Type_Declaration,
17318 N_Protected_Type_Declaration)
17321 ("completion of nonlimited type cannot be limited", N);
17323 elsif Ekind (Prev) = E_Record_Type_With_Private
17324 and then Nkind_In (N, N_Task_Type_Declaration,
17325 N_Protected_Type_Declaration)
17327 if not Is_Limited_Record (Prev) then
17329 ("completion of nonlimited type cannot be limited", N);
17331 elsif No (Interface_List (N)) then
17333 ("completion of tagged private type must be tagged",
17338 -- Ada 2005 (AI-251): Private extension declaration of a task
17339 -- type or a protected type. This case arises when covering
17340 -- interface types.
17342 elsif Nkind_In (N, N_Task_Type_Declaration,
17343 N_Protected_Type_Declaration)
17347 elsif Nkind (N) /= N_Full_Type_Declaration
17348 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
17351 ("full view of private extension must be an extension", N);
17353 elsif not (Abstract_Present (Parent (Prev)))
17354 and then Abstract_Present (Type_Definition (N))
17357 ("full view of non-abstract extension cannot be abstract", N);
17360 if not In_Private_Part (Current_Scope) then
17362 ("declaration of full view must appear in private part", N);
17365 if Ada_Version >= Ada_2012 then
17366 Check_Duplicate_Aspects;
17369 Copy_And_Swap (Prev, Id);
17370 Set_Has_Private_Declaration (Prev);
17371 Set_Has_Private_Declaration (Id);
17373 -- AI12-0133: Indicate whether we have a partial view with
17374 -- unknown discriminants, in which case initialization of objects
17375 -- of the type do not receive an invariant check.
17377 Set_Partial_View_Has_Unknown_Discr
17378 (Prev, Has_Unknown_Discriminants (Id));
17380 -- Preserve aspect and iterator flags that may have been set on
17381 -- the partial view.
17383 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
17384 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
17386 -- If no error, propagate freeze_node from private to full view.
17387 -- It may have been generated for an early operational item.
17389 if Present (Freeze_Node (Id))
17390 and then Serious_Errors_Detected = 0
17391 and then No (Full_View (Id))
17393 Set_Freeze_Node (Prev, Freeze_Node (Id));
17394 Set_Freeze_Node (Id, Empty);
17395 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
17398 Set_Full_View (Id, Prev);
17402 -- Verify that full declaration conforms to partial one
17404 if Is_Incomplete_Or_Private_Type (Prev)
17405 and then Present (Discriminant_Specifications (Prev_Par))
17407 if Present (Discriminant_Specifications (N)) then
17408 if Ekind (Prev) = E_Incomplete_Type then
17409 Check_Discriminant_Conformance (N, Prev, Prev);
17411 Check_Discriminant_Conformance (N, Prev, Id);
17416 ("missing discriminants in full type declaration", N);
17418 -- To avoid cascaded errors on subsequent use, share the
17419 -- discriminants of the partial view.
17421 Set_Discriminant_Specifications (N,
17422 Discriminant_Specifications (Prev_Par));
17426 -- A prior untagged partial view can have an associated class-wide
17427 -- type due to use of the class attribute, and in this case the full
17428 -- type must also be tagged. This Ada 95 usage is deprecated in favor
17429 -- of incomplete tagged declarations, but we check for it.
17432 and then (Is_Tagged_Type (Prev)
17433 or else Present (Class_Wide_Type (Prev)))
17435 -- Ada 2012 (AI05-0162): A private type may be the completion of
17436 -- an incomplete type.
17438 if Ada_Version >= Ada_2012
17439 and then Is_Incomplete_Type (Prev)
17440 and then Nkind_In (N, N_Private_Type_Declaration,
17441 N_Private_Extension_Declaration)
17443 -- No need to check private extensions since they are tagged
17445 if Nkind (N) = N_Private_Type_Declaration
17446 and then not Tagged_Present (N)
17451 -- The full declaration is either a tagged type (including
17452 -- a synchronized type that implements interfaces) or a
17453 -- type extension, otherwise this is an error.
17455 elsif Nkind_In (N, N_Task_Type_Declaration,
17456 N_Protected_Type_Declaration)
17458 if No (Interface_List (N)) and then not Error_Posted (N) then
17462 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
17464 -- Indicate that the previous declaration (tagged incomplete
17465 -- or private declaration) requires the same on the full one.
17467 if not Tagged_Present (Type_Definition (N)) then
17469 Set_Is_Tagged_Type (Id);
17472 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
17473 if No (Record_Extension_Part (Type_Definition (N))) then
17475 ("full declaration of } must be a record extension",
17478 -- Set some attributes to produce a usable full view
17480 Set_Is_Tagged_Type (Id);
17489 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
17490 and then Present (Premature_Use (Parent (Prev)))
17492 Error_Msg_Sloc := Sloc (N);
17494 ("\full declaration #", Premature_Use (Parent (Prev)));
17499 end Find_Type_Name;
17501 -------------------------
17502 -- Find_Type_Of_Object --
17503 -------------------------
17505 function Find_Type_Of_Object
17506 (Obj_Def : Node_Id;
17507 Related_Nod : Node_Id) return Entity_Id
17509 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
17510 P : Node_Id := Parent (Obj_Def);
17515 -- If the parent is a component_definition node we climb to the
17516 -- component_declaration node
17518 if Nkind (P) = N_Component_Definition then
17522 -- Case of an anonymous array subtype
17524 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
17525 N_Unconstrained_Array_Definition)
17528 Array_Type_Declaration (T, Obj_Def);
17530 -- Create an explicit subtype whenever possible
17532 elsif Nkind (P) /= N_Component_Declaration
17533 and then Def_Kind = N_Subtype_Indication
17535 -- Base name of subtype on object name, which will be unique in
17536 -- the current scope.
17538 -- If this is a duplicate declaration, return base type, to avoid
17539 -- generating duplicate anonymous types.
17541 if Error_Posted (P) then
17542 Analyze (Subtype_Mark (Obj_Def));
17543 return Entity (Subtype_Mark (Obj_Def));
17548 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
17550 T := Make_Defining_Identifier (Sloc (P), Nam);
17552 Insert_Action (Obj_Def,
17553 Make_Subtype_Declaration (Sloc (P),
17554 Defining_Identifier => T,
17555 Subtype_Indication => Relocate_Node (Obj_Def)));
17557 -- This subtype may need freezing, and this will not be done
17558 -- automatically if the object declaration is not in declarative
17559 -- part. Since this is an object declaration, the type cannot always
17560 -- be frozen here. Deferred constants do not freeze their type
17561 -- (which often enough will be private).
17563 if Nkind (P) = N_Object_Declaration
17564 and then Constant_Present (P)
17565 and then No (Expression (P))
17569 -- Here we freeze the base type of object type to catch premature use
17570 -- of discriminated private type without a full view.
17573 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
17576 -- Ada 2005 AI-406: the object definition in an object declaration
17577 -- can be an access definition.
17579 elsif Def_Kind = N_Access_Definition then
17580 T := Access_Definition (Related_Nod, Obj_Def);
17582 Set_Is_Local_Anonymous_Access
17584 V => (Ada_Version < Ada_2012)
17585 or else (Nkind (P) /= N_Object_Declaration)
17586 or else Is_Library_Level_Entity (Defining_Identifier (P)));
17588 -- Otherwise, the object definition is just a subtype_mark
17591 T := Process_Subtype (Obj_Def, Related_Nod);
17593 -- If expansion is disabled an object definition that is an aggregate
17594 -- will not get expanded and may lead to scoping problems in the back
17595 -- end, if the object is referenced in an inner scope. In that case
17596 -- create an itype reference for the object definition now. This
17597 -- may be redundant in some cases, but harmless.
17600 and then Nkind (Related_Nod) = N_Object_Declaration
17603 Build_Itype_Reference (T, Related_Nod);
17608 end Find_Type_Of_Object;
17610 --------------------------------
17611 -- Find_Type_Of_Subtype_Indic --
17612 --------------------------------
17614 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
17618 -- Case of subtype mark with a constraint
17620 if Nkind (S) = N_Subtype_Indication then
17621 Find_Type (Subtype_Mark (S));
17622 Typ := Entity (Subtype_Mark (S));
17625 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
17628 ("incorrect constraint for this kind of type", Constraint (S));
17629 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17632 -- Otherwise we have a subtype mark without a constraint
17634 elsif Error_Posted (S) then
17635 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
17643 -- Check No_Wide_Characters restriction
17645 Check_Wide_Character_Restriction (Typ, S);
17648 end Find_Type_Of_Subtype_Indic;
17650 -------------------------------------
17651 -- Floating_Point_Type_Declaration --
17652 -------------------------------------
17654 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17655 Digs : constant Node_Id := Digits_Expression (Def);
17656 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
17658 Base_Typ : Entity_Id;
17659 Implicit_Base : Entity_Id;
17662 function Can_Derive_From (E : Entity_Id) return Boolean;
17663 -- Find if given digits value, and possibly a specified range, allows
17664 -- derivation from specified type
17666 function Find_Base_Type return Entity_Id;
17667 -- Find a predefined base type that Def can derive from, or generate
17668 -- an error and substitute Long_Long_Float if none exists.
17670 ---------------------
17671 -- Can_Derive_From --
17672 ---------------------
17674 function Can_Derive_From (E : Entity_Id) return Boolean is
17675 Spec : constant Entity_Id := Real_Range_Specification (Def);
17678 -- Check specified "digits" constraint
17680 if Digs_Val > Digits_Value (E) then
17684 -- Check for matching range, if specified
17686 if Present (Spec) then
17687 if Expr_Value_R (Type_Low_Bound (E)) >
17688 Expr_Value_R (Low_Bound (Spec))
17693 if Expr_Value_R (Type_High_Bound (E)) <
17694 Expr_Value_R (High_Bound (Spec))
17701 end Can_Derive_From;
17703 --------------------
17704 -- Find_Base_Type --
17705 --------------------
17707 function Find_Base_Type return Entity_Id is
17708 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
17711 -- Iterate over the predefined types in order, returning the first
17712 -- one that Def can derive from.
17714 while Present (Choice) loop
17715 if Can_Derive_From (Node (Choice)) then
17716 return Node (Choice);
17719 Next_Elmt (Choice);
17722 -- If we can't derive from any existing type, use Long_Long_Float
17723 -- and give appropriate message explaining the problem.
17725 if Digs_Val > Max_Digs_Val then
17726 -- It might be the case that there is a type with the requested
17727 -- range, just not the combination of digits and range.
17730 ("no predefined type has requested range and precision",
17731 Real_Range_Specification (Def));
17735 ("range too large for any predefined type",
17736 Real_Range_Specification (Def));
17739 return Standard_Long_Long_Float;
17740 end Find_Base_Type;
17742 -- Start of processing for Floating_Point_Type_Declaration
17745 Check_Restriction (No_Floating_Point, Def);
17747 -- Create an implicit base type
17750 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
17752 -- Analyze and verify digits value
17754 Analyze_And_Resolve (Digs, Any_Integer);
17755 Check_Digits_Expression (Digs);
17756 Digs_Val := Expr_Value (Digs);
17758 -- Process possible range spec and find correct type to derive from
17760 Process_Real_Range_Specification (Def);
17762 -- Check that requested number of digits is not too high.
17764 if Digs_Val > Max_Digs_Val then
17766 -- The check for Max_Base_Digits may be somewhat expensive, as it
17767 -- requires reading System, so only do it when necessary.
17770 Max_Base_Digits : constant Uint :=
17773 (Parent (RTE (RE_Max_Base_Digits))));
17776 if Digs_Val > Max_Base_Digits then
17777 Error_Msg_Uint_1 := Max_Base_Digits;
17778 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17780 elsif No (Real_Range_Specification (Def)) then
17781 Error_Msg_Uint_1 := Max_Digs_Val;
17782 Error_Msg_N ("types with more than ^ digits need range spec "
17783 & "(RM 3.5.7(6))", Digs);
17788 -- Find a suitable type to derive from or complain and use a substitute
17790 Base_Typ := Find_Base_Type;
17792 -- If there are bounds given in the declaration use them as the bounds
17793 -- of the type, otherwise use the bounds of the predefined base type
17794 -- that was chosen based on the Digits value.
17796 if Present (Real_Range_Specification (Def)) then
17797 Set_Scalar_Range (T, Real_Range_Specification (Def));
17798 Set_Is_Constrained (T);
17800 -- The bounds of this range must be converted to machine numbers
17801 -- in accordance with RM 4.9(38).
17803 Bound := Type_Low_Bound (T);
17805 if Nkind (Bound) = N_Real_Literal then
17807 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17808 Set_Is_Machine_Number (Bound);
17811 Bound := Type_High_Bound (T);
17813 if Nkind (Bound) = N_Real_Literal then
17815 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17816 Set_Is_Machine_Number (Bound);
17820 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17823 -- Complete definition of implicit base and declared first subtype. The
17824 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17825 -- are not clobbered when the floating point type acts as a full view of
17828 Set_Etype (Implicit_Base, Base_Typ);
17829 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17830 Set_Size_Info (Implicit_Base, Base_Typ);
17831 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17832 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17833 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17834 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17836 Set_Ekind (T, E_Floating_Point_Subtype);
17837 Set_Etype (T, Implicit_Base);
17838 Set_Size_Info (T, Implicit_Base);
17839 Set_RM_Size (T, RM_Size (Implicit_Base));
17840 Inherit_Rep_Item_Chain (T, Implicit_Base);
17841 Set_Digits_Value (T, Digs_Val);
17842 end Floating_Point_Type_Declaration;
17844 ----------------------------
17845 -- Get_Discriminant_Value --
17846 ----------------------------
17848 -- This is the situation:
17850 -- There is a non-derived type
17852 -- type T0 (Dx, Dy, Dz...)
17854 -- There are zero or more levels of derivation, with each derivation
17855 -- either purely inheriting the discriminants, or defining its own.
17857 -- type Ti is new Ti-1
17859 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17861 -- subtype Ti is ...
17863 -- The subtype issue is avoided by the use of Original_Record_Component,
17864 -- and the fact that derived subtypes also derive the constraints.
17866 -- This chain leads back from
17868 -- Typ_For_Constraint
17870 -- Typ_For_Constraint has discriminants, and the value for each
17871 -- discriminant is given by its corresponding Elmt of Constraints.
17873 -- Discriminant is some discriminant in this hierarchy
17875 -- We need to return its value
17877 -- We do this by recursively searching each level, and looking for
17878 -- Discriminant. Once we get to the bottom, we start backing up
17879 -- returning the value for it which may in turn be a discriminant
17880 -- further up, so on the backup we continue the substitution.
17882 function Get_Discriminant_Value
17883 (Discriminant : Entity_Id;
17884 Typ_For_Constraint : Entity_Id;
17885 Constraint : Elist_Id) return Node_Id
17887 function Root_Corresponding_Discriminant
17888 (Discr : Entity_Id) return Entity_Id;
17889 -- Given a discriminant, traverse the chain of inherited discriminants
17890 -- and return the topmost discriminant.
17892 function Search_Derivation_Levels
17894 Discrim_Values : Elist_Id;
17895 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17896 -- This is the routine that performs the recursive search of levels
17897 -- as described above.
17899 -------------------------------------
17900 -- Root_Corresponding_Discriminant --
17901 -------------------------------------
17903 function Root_Corresponding_Discriminant
17904 (Discr : Entity_Id) return Entity_Id
17910 while Present (Corresponding_Discriminant (D)) loop
17911 D := Corresponding_Discriminant (D);
17915 end Root_Corresponding_Discriminant;
17917 ------------------------------
17918 -- Search_Derivation_Levels --
17919 ------------------------------
17921 function Search_Derivation_Levels
17923 Discrim_Values : Elist_Id;
17924 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17928 Result : Node_Or_Entity_Id;
17929 Result_Entity : Node_Id;
17932 -- If inappropriate type, return Error, this happens only in
17933 -- cascaded error situations, and we want to avoid a blow up.
17935 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17939 -- Look deeper if possible. Use Stored_Constraints only for
17940 -- untagged types. For tagged types use the given constraint.
17941 -- This asymmetry needs explanation???
17943 if not Stored_Discrim_Values
17944 and then Present (Stored_Constraint (Ti))
17945 and then not Is_Tagged_Type (Ti)
17948 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17951 Td : constant Entity_Id := Etype (Ti);
17955 Result := Discriminant;
17958 if Present (Stored_Constraint (Ti)) then
17960 Search_Derivation_Levels
17961 (Td, Stored_Constraint (Ti), True);
17964 Search_Derivation_Levels
17965 (Td, Discrim_Values, Stored_Discrim_Values);
17971 -- Extra underlying places to search, if not found above. For
17972 -- concurrent types, the relevant discriminant appears in the
17973 -- corresponding record. For a type derived from a private type
17974 -- without discriminant, the full view inherits the discriminants
17975 -- of the full view of the parent.
17977 if Result = Discriminant then
17978 if Is_Concurrent_Type (Ti)
17979 and then Present (Corresponding_Record_Type (Ti))
17982 Search_Derivation_Levels (
17983 Corresponding_Record_Type (Ti),
17985 Stored_Discrim_Values);
17987 elsif Is_Private_Type (Ti)
17988 and then not Has_Discriminants (Ti)
17989 and then Present (Full_View (Ti))
17990 and then Etype (Full_View (Ti)) /= Ti
17993 Search_Derivation_Levels (
17996 Stored_Discrim_Values);
18000 -- If Result is not a (reference to a) discriminant, return it,
18001 -- otherwise set Result_Entity to the discriminant.
18003 if Nkind (Result) = N_Defining_Identifier then
18004 pragma Assert (Result = Discriminant);
18005 Result_Entity := Result;
18008 if not Denotes_Discriminant (Result) then
18012 Result_Entity := Entity (Result);
18015 -- See if this level of derivation actually has discriminants because
18016 -- tagged derivations can add them, hence the lower levels need not
18019 if not Has_Discriminants (Ti) then
18023 -- Scan Ti's discriminants for Result_Entity, and return its
18024 -- corresponding value, if any.
18026 Result_Entity := Original_Record_Component (Result_Entity);
18028 Assoc := First_Elmt (Discrim_Values);
18030 if Stored_Discrim_Values then
18031 Disc := First_Stored_Discriminant (Ti);
18033 Disc := First_Discriminant (Ti);
18036 while Present (Disc) loop
18038 -- If no further associations return the discriminant, value will
18039 -- be found on the second pass.
18045 if Original_Record_Component (Disc) = Result_Entity then
18046 return Node (Assoc);
18051 if Stored_Discrim_Values then
18052 Next_Stored_Discriminant (Disc);
18054 Next_Discriminant (Disc);
18058 -- Could not find it
18061 end Search_Derivation_Levels;
18065 Result : Node_Or_Entity_Id;
18067 -- Start of processing for Get_Discriminant_Value
18070 -- ??? This routine is a gigantic mess and will be deleted. For the
18071 -- time being just test for the trivial case before calling recurse.
18073 -- We are now celebrating the 20th anniversary of this comment!
18075 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
18081 D := First_Discriminant (Typ_For_Constraint);
18082 E := First_Elmt (Constraint);
18083 while Present (D) loop
18084 if Chars (D) = Chars (Discriminant) then
18088 Next_Discriminant (D);
18094 Result := Search_Derivation_Levels
18095 (Typ_For_Constraint, Constraint, False);
18097 -- ??? hack to disappear when this routine is gone
18099 if Nkind (Result) = N_Defining_Identifier then
18105 D := First_Discriminant (Typ_For_Constraint);
18106 E := First_Elmt (Constraint);
18107 while Present (D) loop
18108 if Root_Corresponding_Discriminant (D) = Discriminant then
18112 Next_Discriminant (D);
18118 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
18120 end Get_Discriminant_Value;
18122 --------------------------
18123 -- Has_Range_Constraint --
18124 --------------------------
18126 function Has_Range_Constraint (N : Node_Id) return Boolean is
18127 C : constant Node_Id := Constraint (N);
18130 if Nkind (C) = N_Range_Constraint then
18133 elsif Nkind (C) = N_Digits_Constraint then
18135 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
18136 or else Present (Range_Constraint (C));
18138 elsif Nkind (C) = N_Delta_Constraint then
18139 return Present (Range_Constraint (C));
18144 end Has_Range_Constraint;
18146 ------------------------
18147 -- Inherit_Components --
18148 ------------------------
18150 function Inherit_Components
18152 Parent_Base : Entity_Id;
18153 Derived_Base : Entity_Id;
18154 Is_Tagged : Boolean;
18155 Inherit_Discr : Boolean;
18156 Discs : Elist_Id) return Elist_Id
18158 Assoc_List : constant Elist_Id := New_Elmt_List;
18160 procedure Inherit_Component
18161 (Old_C : Entity_Id;
18162 Plain_Discrim : Boolean := False;
18163 Stored_Discrim : Boolean := False);
18164 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
18165 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
18166 -- True, Old_C is a stored discriminant. If they are both false then
18167 -- Old_C is a regular component.
18169 -----------------------
18170 -- Inherit_Component --
18171 -----------------------
18173 procedure Inherit_Component
18174 (Old_C : Entity_Id;
18175 Plain_Discrim : Boolean := False;
18176 Stored_Discrim : Boolean := False)
18178 procedure Set_Anonymous_Type (Id : Entity_Id);
18179 -- Id denotes the entity of an access discriminant or anonymous
18180 -- access component. Set the type of Id to either the same type of
18181 -- Old_C or create a new one depending on whether the parent and
18182 -- the child types are in the same scope.
18184 ------------------------
18185 -- Set_Anonymous_Type --
18186 ------------------------
18188 procedure Set_Anonymous_Type (Id : Entity_Id) is
18189 Old_Typ : constant Entity_Id := Etype (Old_C);
18192 if Scope (Parent_Base) = Scope (Derived_Base) then
18193 Set_Etype (Id, Old_Typ);
18195 -- The parent and the derived type are in two different scopes.
18196 -- Reuse the type of the original discriminant / component by
18197 -- copying it in order to preserve all attributes.
18201 Typ : constant Entity_Id := New_Copy (Old_Typ);
18204 Set_Etype (Id, Typ);
18206 -- Since we do not generate component declarations for
18207 -- inherited components, associate the itype with the
18210 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
18211 Set_Scope (Typ, Derived_Base);
18214 end Set_Anonymous_Type;
18216 -- Local variables and constants
18218 New_C : constant Entity_Id := New_Copy (Old_C);
18220 Corr_Discrim : Entity_Id;
18221 Discrim : Entity_Id;
18223 -- Start of processing for Inherit_Component
18226 pragma Assert (not Is_Tagged or not Stored_Discrim);
18228 Set_Parent (New_C, Parent (Old_C));
18230 -- Regular discriminants and components must be inserted in the scope
18231 -- of the Derived_Base. Do it here.
18233 if not Stored_Discrim then
18234 Enter_Name (New_C);
18237 -- For tagged types the Original_Record_Component must point to
18238 -- whatever this field was pointing to in the parent type. This has
18239 -- already been achieved by the call to New_Copy above.
18241 if not Is_Tagged then
18242 Set_Original_Record_Component (New_C, New_C);
18243 Set_Corresponding_Record_Component (New_C, Old_C);
18246 -- Set the proper type of an access discriminant
18248 if Ekind (New_C) = E_Discriminant
18249 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
18251 Set_Anonymous_Type (New_C);
18254 -- If we have inherited a component then see if its Etype contains
18255 -- references to Parent_Base discriminants. In this case, replace
18256 -- these references with the constraints given in Discs. We do not
18257 -- do this for the partial view of private types because this is
18258 -- not needed (only the components of the full view will be used
18259 -- for code generation) and cause problem. We also avoid this
18260 -- transformation in some error situations.
18262 if Ekind (New_C) = E_Component then
18264 -- Set the proper type of an anonymous access component
18266 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
18267 Set_Anonymous_Type (New_C);
18269 elsif (Is_Private_Type (Derived_Base)
18270 and then not Is_Generic_Type (Derived_Base))
18271 or else (Is_Empty_Elmt_List (Discs)
18272 and then not Expander_Active)
18274 Set_Etype (New_C, Etype (Old_C));
18277 -- The current component introduces a circularity of the
18280 -- limited with Pack_2;
18281 -- package Pack_1 is
18282 -- type T_1 is tagged record
18283 -- Comp : access Pack_2.T_2;
18289 -- package Pack_2 is
18290 -- type T_2 is new Pack_1.T_1 with ...;
18295 Constrain_Component_Type
18296 (Old_C, Derived_Base, N, Parent_Base, Discs));
18300 -- In derived tagged types it is illegal to reference a non
18301 -- discriminant component in the parent type. To catch this, mark
18302 -- these components with an Ekind of E_Void. This will be reset in
18303 -- Record_Type_Definition after processing the record extension of
18304 -- the derived type.
18306 -- If the declaration is a private extension, there is no further
18307 -- record extension to process, and the components retain their
18308 -- current kind, because they are visible at this point.
18310 if Is_Tagged and then Ekind (New_C) = E_Component
18311 and then Nkind (N) /= N_Private_Extension_Declaration
18313 Set_Ekind (New_C, E_Void);
18316 if Plain_Discrim then
18317 Set_Corresponding_Discriminant (New_C, Old_C);
18318 Build_Discriminal (New_C);
18320 -- If we are explicitly inheriting a stored discriminant it will be
18321 -- completely hidden.
18323 elsif Stored_Discrim then
18324 Set_Corresponding_Discriminant (New_C, Empty);
18325 Set_Discriminal (New_C, Empty);
18326 Set_Is_Completely_Hidden (New_C);
18328 -- Set the Original_Record_Component of each discriminant in the
18329 -- derived base to point to the corresponding stored that we just
18332 Discrim := First_Discriminant (Derived_Base);
18333 while Present (Discrim) loop
18334 Corr_Discrim := Corresponding_Discriminant (Discrim);
18336 -- Corr_Discrim could be missing in an error situation
18338 if Present (Corr_Discrim)
18339 and then Original_Record_Component (Corr_Discrim) = Old_C
18341 Set_Original_Record_Component (Discrim, New_C);
18342 Set_Corresponding_Record_Component (Discrim, Empty);
18345 Next_Discriminant (Discrim);
18348 Append_Entity (New_C, Derived_Base);
18351 if not Is_Tagged then
18352 Append_Elmt (Old_C, Assoc_List);
18353 Append_Elmt (New_C, Assoc_List);
18355 end Inherit_Component;
18357 -- Variables local to Inherit_Component
18359 Loc : constant Source_Ptr := Sloc (N);
18361 Parent_Discrim : Entity_Id;
18362 Stored_Discrim : Entity_Id;
18364 Component : Entity_Id;
18366 -- Start of processing for Inherit_Components
18369 if not Is_Tagged then
18370 Append_Elmt (Parent_Base, Assoc_List);
18371 Append_Elmt (Derived_Base, Assoc_List);
18374 -- Inherit parent discriminants if needed
18376 if Inherit_Discr then
18377 Parent_Discrim := First_Discriminant (Parent_Base);
18378 while Present (Parent_Discrim) loop
18379 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
18380 Next_Discriminant (Parent_Discrim);
18384 -- Create explicit stored discrims for untagged types when necessary
18386 if not Has_Unknown_Discriminants (Derived_Base)
18387 and then Has_Discriminants (Parent_Base)
18388 and then not Is_Tagged
18391 or else First_Discriminant (Parent_Base) /=
18392 First_Stored_Discriminant (Parent_Base))
18394 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
18395 while Present (Stored_Discrim) loop
18396 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
18397 Next_Stored_Discriminant (Stored_Discrim);
18401 -- See if we can apply the second transformation for derived types, as
18402 -- explained in point 6. in the comments above Build_Derived_Record_Type
18403 -- This is achieved by appending Derived_Base discriminants into Discs,
18404 -- which has the side effect of returning a non empty Discs list to the
18405 -- caller of Inherit_Components, which is what we want. This must be
18406 -- done for private derived types if there are explicit stored
18407 -- discriminants, to ensure that we can retrieve the values of the
18408 -- constraints provided in the ancestors.
18411 and then Is_Empty_Elmt_List (Discs)
18412 and then Present (First_Discriminant (Derived_Base))
18414 (not Is_Private_Type (Derived_Base)
18415 or else Is_Completely_Hidden
18416 (First_Stored_Discriminant (Derived_Base))
18417 or else Is_Generic_Type (Derived_Base))
18419 D := First_Discriminant (Derived_Base);
18420 while Present (D) loop
18421 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
18422 Next_Discriminant (D);
18426 -- Finally, inherit non-discriminant components unless they are not
18427 -- visible because defined or inherited from the full view of the
18428 -- parent. Don't inherit the _parent field of the parent type.
18430 Component := First_Entity (Parent_Base);
18431 while Present (Component) loop
18433 -- Ada 2005 (AI-251): Do not inherit components associated with
18434 -- secondary tags of the parent.
18436 if Ekind (Component) = E_Component
18437 and then Present (Related_Type (Component))
18441 elsif Ekind (Component) /= E_Component
18442 or else Chars (Component) = Name_uParent
18446 -- If the derived type is within the parent type's declarative
18447 -- region, then the components can still be inherited even though
18448 -- they aren't visible at this point. This can occur for cases
18449 -- such as within public child units where the components must
18450 -- become visible upon entering the child unit's private part.
18452 elsif not Is_Visible_Component (Component)
18453 and then not In_Open_Scopes (Scope (Parent_Base))
18457 elsif Ekind_In (Derived_Base, E_Private_Type,
18458 E_Limited_Private_Type)
18463 Inherit_Component (Component);
18466 Next_Entity (Component);
18469 -- For tagged derived types, inherited discriminants cannot be used in
18470 -- component declarations of the record extension part. To achieve this
18471 -- we mark the inherited discriminants as not visible.
18473 if Is_Tagged and then Inherit_Discr then
18474 D := First_Discriminant (Derived_Base);
18475 while Present (D) loop
18476 Set_Is_Immediately_Visible (D, False);
18477 Next_Discriminant (D);
18482 end Inherit_Components;
18484 -----------------------------
18485 -- Inherit_Predicate_Flags --
18486 -----------------------------
18488 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
18490 Set_Has_Predicates (Subt, Has_Predicates (Par));
18491 Set_Has_Static_Predicate_Aspect
18492 (Subt, Has_Static_Predicate_Aspect (Par));
18493 Set_Has_Dynamic_Predicate_Aspect
18494 (Subt, Has_Dynamic_Predicate_Aspect (Par));
18496 -- A named subtype does not inherit the predicate function of its
18497 -- parent but an itype declared for a loop index needs the discrete
18498 -- predicate information of its parent to execute the loop properly.
18500 if Is_Itype (Subt) and then Present (Predicate_Function (Par)) then
18501 Set_Subprograms_For_Type (Subt, Subprograms_For_Type (Par));
18503 if Has_Static_Predicate (Par) then
18504 Set_Static_Discrete_Predicate
18505 (Subt, Static_Discrete_Predicate (Par));
18508 end Inherit_Predicate_Flags;
18510 ----------------------
18511 -- Is_EVF_Procedure --
18512 ----------------------
18514 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
18515 Formal : Entity_Id;
18518 -- Examine the formals of an Extensions_Visible False procedure looking
18519 -- for a controlling OUT parameter.
18521 if Ekind (Subp) = E_Procedure
18522 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
18524 Formal := First_Formal (Subp);
18525 while Present (Formal) loop
18526 if Ekind (Formal) = E_Out_Parameter
18527 and then Is_Controlling_Formal (Formal)
18532 Next_Formal (Formal);
18537 end Is_EVF_Procedure;
18539 -----------------------
18540 -- Is_Null_Extension --
18541 -----------------------
18543 function Is_Null_Extension (T : Entity_Id) return Boolean is
18544 Type_Decl : constant Node_Id := Parent (Base_Type (T));
18545 Comp_List : Node_Id;
18549 if Nkind (Type_Decl) /= N_Full_Type_Declaration
18550 or else not Is_Tagged_Type (T)
18551 or else Nkind (Type_Definition (Type_Decl)) /=
18552 N_Derived_Type_Definition
18553 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
18559 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
18561 if Present (Discriminant_Specifications (Type_Decl)) then
18564 elsif Present (Comp_List)
18565 and then Is_Non_Empty_List (Component_Items (Comp_List))
18567 Comp := First (Component_Items (Comp_List));
18569 -- Only user-defined components are relevant. The component list
18570 -- may also contain a parent component and internal components
18571 -- corresponding to secondary tags, but these do not determine
18572 -- whether this is a null extension.
18574 while Present (Comp) loop
18575 if Comes_From_Source (Comp) then
18587 end Is_Null_Extension;
18589 ------------------------------
18590 -- Is_Valid_Constraint_Kind --
18591 ------------------------------
18593 function Is_Valid_Constraint_Kind
18594 (T_Kind : Type_Kind;
18595 Constraint_Kind : Node_Kind) return Boolean
18599 when Enumeration_Kind
18602 return Constraint_Kind = N_Range_Constraint;
18604 when Decimal_Fixed_Point_Kind =>
18605 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18606 N_Range_Constraint);
18608 when Ordinary_Fixed_Point_Kind =>
18609 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
18610 N_Range_Constraint);
18613 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18614 N_Range_Constraint);
18621 | E_Incomplete_Type
18625 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
18628 return True; -- Error will be detected later
18630 end Is_Valid_Constraint_Kind;
18632 --------------------------
18633 -- Is_Visible_Component --
18634 --------------------------
18636 function Is_Visible_Component
18638 N : Node_Id := Empty) return Boolean
18640 Original_Comp : Entity_Id := Empty;
18641 Original_Type : Entity_Id;
18642 Type_Scope : Entity_Id;
18644 function Is_Local_Type (Typ : Entity_Id) return Boolean;
18645 -- Check whether parent type of inherited component is declared locally,
18646 -- possibly within a nested package or instance. The current scope is
18647 -- the derived record itself.
18649 -------------------
18650 -- Is_Local_Type --
18651 -------------------
18653 function Is_Local_Type (Typ : Entity_Id) return Boolean is
18657 Scop := Scope (Typ);
18658 while Present (Scop)
18659 and then Scop /= Standard_Standard
18661 if Scop = Scope (Current_Scope) then
18665 Scop := Scope (Scop);
18671 -- Start of processing for Is_Visible_Component
18674 if Ekind_In (C, E_Component, E_Discriminant) then
18675 Original_Comp := Original_Record_Component (C);
18678 if No (Original_Comp) then
18680 -- Premature usage, or previous error
18685 Original_Type := Scope (Original_Comp);
18686 Type_Scope := Scope (Base_Type (Scope (C)));
18689 -- This test only concerns tagged types
18691 if not Is_Tagged_Type (Original_Type) then
18694 -- If it is _Parent or _Tag, there is no visibility issue
18696 elsif not Comes_From_Source (Original_Comp) then
18699 -- Discriminants are visible unless the (private) type has unknown
18700 -- discriminants. If the discriminant reference is inserted for a
18701 -- discriminant check on a full view it is also visible.
18703 elsif Ekind (Original_Comp) = E_Discriminant
18705 (not Has_Unknown_Discriminants (Original_Type)
18706 or else (Present (N)
18707 and then Nkind (N) = N_Selected_Component
18708 and then Nkind (Prefix (N)) = N_Type_Conversion
18709 and then not Comes_From_Source (Prefix (N))))
18713 -- In the body of an instantiation, check the visibility of a component
18714 -- in case it has a homograph that is a primitive operation of a private
18715 -- type which was not visible in the generic unit.
18717 -- Should Is_Prefixed_Call be propagated from template to instance???
18719 elsif In_Instance_Body then
18720 if not Is_Tagged_Type (Original_Type)
18721 or else not Is_Private_Type (Original_Type)
18727 Subp_Elmt : Elmt_Id;
18730 Subp_Elmt := First_Elmt (Primitive_Operations (Original_Type));
18731 while Present (Subp_Elmt) loop
18733 -- The component is hidden by a primitive operation
18735 if Chars (Node (Subp_Elmt)) = Chars (C) then
18739 Next_Elmt (Subp_Elmt);
18746 -- If the component has been declared in an ancestor which is currently
18747 -- a private type, then it is not visible. The same applies if the
18748 -- component's containing type is not in an open scope and the original
18749 -- component's enclosing type is a visible full view of a private type
18750 -- (which can occur in cases where an attempt is being made to reference
18751 -- a component in a sibling package that is inherited from a visible
18752 -- component of a type in an ancestor package; the component in the
18753 -- sibling package should not be visible even though the component it
18754 -- inherited from is visible). This does not apply however in the case
18755 -- where the scope of the type is a private child unit, or when the
18756 -- parent comes from a local package in which the ancestor is currently
18757 -- visible. The latter suppression of visibility is needed for cases
18758 -- that are tested in B730006.
18760 elsif Is_Private_Type (Original_Type)
18762 (not Is_Private_Descendant (Type_Scope)
18763 and then not In_Open_Scopes (Type_Scope)
18764 and then Has_Private_Declaration (Original_Type))
18766 -- If the type derives from an entity in a formal package, there
18767 -- are no additional visible components.
18769 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
18770 N_Formal_Package_Declaration
18774 -- if we are not in the private part of the current package, there
18775 -- are no additional visible components.
18777 elsif Ekind (Scope (Current_Scope)) = E_Package
18778 and then not In_Private_Part (Scope (Current_Scope))
18783 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
18784 and then In_Open_Scopes (Scope (Original_Type))
18785 and then Is_Local_Type (Type_Scope);
18788 -- There is another weird way in which a component may be invisible when
18789 -- the private and the full view are not derived from the same ancestor.
18790 -- Here is an example :
18792 -- type A1 is tagged record F1 : integer; end record;
18793 -- type A2 is new A1 with record F2 : integer; end record;
18794 -- type T is new A1 with private;
18796 -- type T is new A2 with null record;
18798 -- In this case, the full view of T inherits F1 and F2 but the private
18799 -- view inherits only F1
18803 Ancestor : Entity_Id := Scope (C);
18807 if Ancestor = Original_Type then
18810 -- The ancestor may have a partial view of the original type,
18811 -- but if the full view is in scope, as in a child body, the
18812 -- component is visible.
18814 elsif In_Private_Part (Scope (Original_Type))
18815 and then Full_View (Ancestor) = Original_Type
18819 elsif Ancestor = Etype (Ancestor) then
18821 -- No further ancestors to examine
18826 Ancestor := Etype (Ancestor);
18830 end Is_Visible_Component;
18832 --------------------------
18833 -- Make_Class_Wide_Type --
18834 --------------------------
18836 procedure Make_Class_Wide_Type (T : Entity_Id) is
18837 CW_Type : Entity_Id;
18839 Next_E : Entity_Id;
18842 if Present (Class_Wide_Type (T)) then
18844 -- The class-wide type is a partially decorated entity created for a
18845 -- unanalyzed tagged type referenced through a limited with clause.
18846 -- When the tagged type is analyzed, its class-wide type needs to be
18847 -- redecorated. Note that we reuse the entity created by Decorate_
18848 -- Tagged_Type in order to preserve all links.
18850 if Materialize_Entity (Class_Wide_Type (T)) then
18851 CW_Type := Class_Wide_Type (T);
18852 Set_Materialize_Entity (CW_Type, False);
18854 -- The class wide type can have been defined by the partial view, in
18855 -- which case everything is already done.
18861 -- Default case, we need to create a new class-wide type
18865 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18868 -- Inherit root type characteristics
18870 CW_Name := Chars (CW_Type);
18871 Next_E := Next_Entity (CW_Type);
18872 Copy_Node (T, CW_Type);
18873 Set_Comes_From_Source (CW_Type, False);
18874 Set_Chars (CW_Type, CW_Name);
18875 Set_Parent (CW_Type, Parent (T));
18876 Set_Next_Entity (CW_Type, Next_E);
18878 -- Ensure we have a new freeze node for the class-wide type. The partial
18879 -- view may have freeze action of its own, requiring a proper freeze
18880 -- node, and the same freeze node cannot be shared between the two
18883 Set_Has_Delayed_Freeze (CW_Type);
18884 Set_Freeze_Node (CW_Type, Empty);
18886 -- Customize the class-wide type: It has no prim. op., it cannot be
18887 -- abstract, its Etype points back to the specific root type, and it
18888 -- cannot have any invariants.
18890 Set_Ekind (CW_Type, E_Class_Wide_Type);
18891 Set_Is_Tagged_Type (CW_Type, True);
18892 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18893 Set_Is_Abstract_Type (CW_Type, False);
18894 Set_Is_Constrained (CW_Type, False);
18895 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18896 Set_Default_SSO (CW_Type);
18897 Set_Has_Inheritable_Invariants (CW_Type, False);
18898 Set_Has_Inherited_Invariants (CW_Type, False);
18899 Set_Has_Own_Invariants (CW_Type, False);
18901 if Ekind (T) = E_Class_Wide_Subtype then
18902 Set_Etype (CW_Type, Etype (Base_Type (T)));
18904 Set_Etype (CW_Type, T);
18907 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18909 -- If this is the class_wide type of a constrained subtype, it does
18910 -- not have discriminants.
18912 Set_Has_Discriminants (CW_Type,
18913 Has_Discriminants (T) and then not Is_Constrained (T));
18915 Set_Has_Unknown_Discriminants (CW_Type, True);
18916 Set_Class_Wide_Type (T, CW_Type);
18917 Set_Equivalent_Type (CW_Type, Empty);
18919 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18921 Set_Class_Wide_Type (CW_Type, CW_Type);
18922 end Make_Class_Wide_Type;
18928 procedure Make_Index
18930 Related_Nod : Node_Id;
18931 Related_Id : Entity_Id := Empty;
18932 Suffix_Index : Nat := 1;
18933 In_Iter_Schm : Boolean := False)
18937 Def_Id : Entity_Id := Empty;
18938 Found : Boolean := False;
18941 -- For a discrete range used in a constrained array definition and
18942 -- defined by a range, an implicit conversion to the predefined type
18943 -- INTEGER is assumed if each bound is either a numeric literal, a named
18944 -- number, or an attribute, and the type of both bounds (prior to the
18945 -- implicit conversion) is the type universal_integer. Otherwise, both
18946 -- bounds must be of the same discrete type, other than universal
18947 -- integer; this type must be determinable independently of the
18948 -- context, but using the fact that the type must be discrete and that
18949 -- both bounds must have the same type.
18951 -- Character literals also have a universal type in the absence of
18952 -- of additional context, and are resolved to Standard_Character.
18954 if Nkind (N) = N_Range then
18956 -- The index is given by a range constraint. The bounds are known
18957 -- to be of a consistent type.
18959 if not Is_Overloaded (N) then
18962 -- For universal bounds, choose the specific predefined type
18964 if T = Universal_Integer then
18965 T := Standard_Integer;
18967 elsif T = Any_Character then
18968 Ambiguous_Character (Low_Bound (N));
18970 T := Standard_Character;
18973 -- The node may be overloaded because some user-defined operators
18974 -- are available, but if a universal interpretation exists it is
18975 -- also the selected one.
18977 elsif Universal_Interpretation (N) = Universal_Integer then
18978 T := Standard_Integer;
18984 Ind : Interp_Index;
18988 Get_First_Interp (N, Ind, It);
18989 while Present (It.Typ) loop
18990 if Is_Discrete_Type (It.Typ) then
18993 and then not Covers (It.Typ, T)
18994 and then not Covers (T, It.Typ)
18996 Error_Msg_N ("ambiguous bounds in discrete range", N);
19004 Get_Next_Interp (Ind, It);
19007 if T = Any_Type then
19008 Error_Msg_N ("discrete type required for range", N);
19009 Set_Etype (N, Any_Type);
19012 elsif T = Universal_Integer then
19013 T := Standard_Integer;
19018 if not Is_Discrete_Type (T) then
19019 Error_Msg_N ("discrete type required for range", N);
19020 Set_Etype (N, Any_Type);
19024 if Nkind (Low_Bound (N)) = N_Attribute_Reference
19025 and then Attribute_Name (Low_Bound (N)) = Name_First
19026 and then Is_Entity_Name (Prefix (Low_Bound (N)))
19027 and then Is_Type (Entity (Prefix (Low_Bound (N))))
19028 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
19030 -- The type of the index will be the type of the prefix, as long
19031 -- as the upper bound is 'Last of the same type.
19033 Def_Id := Entity (Prefix (Low_Bound (N)));
19035 if Nkind (High_Bound (N)) /= N_Attribute_Reference
19036 or else Attribute_Name (High_Bound (N)) /= Name_Last
19037 or else not Is_Entity_Name (Prefix (High_Bound (N)))
19038 or else Entity (Prefix (High_Bound (N))) /= Def_Id
19045 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
19047 elsif Nkind (N) = N_Subtype_Indication then
19049 -- The index is given by a subtype with a range constraint
19051 T := Base_Type (Entity (Subtype_Mark (N)));
19053 if not Is_Discrete_Type (T) then
19054 Error_Msg_N ("discrete type required for range", N);
19055 Set_Etype (N, Any_Type);
19059 R := Range_Expression (Constraint (N));
19062 Process_Range_Expr_In_Decl
19063 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
19065 elsif Nkind (N) = N_Attribute_Reference then
19067 -- Catch beginner's error (use of attribute other than 'Range)
19069 if Attribute_Name (N) /= Name_Range then
19070 Error_Msg_N ("expect attribute ''Range", N);
19071 Set_Etype (N, Any_Type);
19075 -- If the node denotes the range of a type mark, that is also the
19076 -- resulting type, and we do not need to create an Itype for it.
19078 if Is_Entity_Name (Prefix (N))
19079 and then Comes_From_Source (N)
19080 and then Is_Type (Entity (Prefix (N)))
19081 and then Is_Discrete_Type (Entity (Prefix (N)))
19083 Def_Id := Entity (Prefix (N));
19086 Analyze_And_Resolve (N);
19090 -- If none of the above, must be a subtype. We convert this to a
19091 -- range attribute reference because in the case of declared first
19092 -- named subtypes, the types in the range reference can be different
19093 -- from the type of the entity. A range attribute normalizes the
19094 -- reference and obtains the correct types for the bounds.
19096 -- This transformation is in the nature of an expansion, is only
19097 -- done if expansion is active. In particular, it is not done on
19098 -- formal generic types, because we need to retain the name of the
19099 -- original index for instantiation purposes.
19102 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
19103 Error_Msg_N ("invalid subtype mark in discrete range ", N);
19104 Set_Etype (N, Any_Integer);
19108 -- The type mark may be that of an incomplete type. It is only
19109 -- now that we can get the full view, previous analysis does
19110 -- not look specifically for a type mark.
19112 Set_Entity (N, Get_Full_View (Entity (N)));
19113 Set_Etype (N, Entity (N));
19114 Def_Id := Entity (N);
19116 if not Is_Discrete_Type (Def_Id) then
19117 Error_Msg_N ("discrete type required for index", N);
19118 Set_Etype (N, Any_Type);
19123 if Expander_Active then
19125 Make_Attribute_Reference (Sloc (N),
19126 Attribute_Name => Name_Range,
19127 Prefix => Relocate_Node (N)));
19129 -- The original was a subtype mark that does not freeze. This
19130 -- means that the rewritten version must not freeze either.
19132 Set_Must_Not_Freeze (N);
19133 Set_Must_Not_Freeze (Prefix (N));
19134 Analyze_And_Resolve (N);
19138 -- If expander is inactive, type is legal, nothing else to construct
19145 if not Is_Discrete_Type (T) then
19146 Error_Msg_N ("discrete type required for range", N);
19147 Set_Etype (N, Any_Type);
19150 elsif T = Any_Type then
19151 Set_Etype (N, Any_Type);
19155 -- We will now create the appropriate Itype to describe the range, but
19156 -- first a check. If we originally had a subtype, then we just label
19157 -- the range with this subtype. Not only is there no need to construct
19158 -- a new subtype, but it is wrong to do so for two reasons:
19160 -- 1. A legality concern, if we have a subtype, it must not freeze,
19161 -- and the Itype would cause freezing incorrectly
19163 -- 2. An efficiency concern, if we created an Itype, it would not be
19164 -- recognized as the same type for the purposes of eliminating
19165 -- checks in some circumstances.
19167 -- We signal this case by setting the subtype entity in Def_Id
19169 if No (Def_Id) then
19171 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
19172 Set_Etype (Def_Id, Base_Type (T));
19174 if Is_Signed_Integer_Type (T) then
19175 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
19177 elsif Is_Modular_Integer_Type (T) then
19178 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
19181 Set_Ekind (Def_Id, E_Enumeration_Subtype);
19182 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
19183 Set_First_Literal (Def_Id, First_Literal (T));
19186 Set_Size_Info (Def_Id, (T));
19187 Set_RM_Size (Def_Id, RM_Size (T));
19188 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
19190 Set_Scalar_Range (Def_Id, R);
19191 Conditional_Delay (Def_Id, T);
19193 if Nkind (N) = N_Subtype_Indication then
19194 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
19197 -- In the subtype indication case, if the immediate parent of the
19198 -- new subtype is non-static, then the subtype we create is non-
19199 -- static, even if its bounds are static.
19201 if Nkind (N) = N_Subtype_Indication
19202 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
19204 Set_Is_Non_Static_Subtype (Def_Id);
19208 -- Final step is to label the index with this constructed type
19210 Set_Etype (N, Def_Id);
19213 ------------------------------
19214 -- Modular_Type_Declaration --
19215 ------------------------------
19217 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19218 Mod_Expr : constant Node_Id := Expression (Def);
19221 procedure Set_Modular_Size (Bits : Int);
19222 -- Sets RM_Size to Bits, and Esize to normal word size above this
19224 ----------------------
19225 -- Set_Modular_Size --
19226 ----------------------
19228 procedure Set_Modular_Size (Bits : Int) is
19230 Set_RM_Size (T, UI_From_Int (Bits));
19235 elsif Bits <= 16 then
19236 Init_Esize (T, 16);
19238 elsif Bits <= 32 then
19239 Init_Esize (T, 32);
19242 Init_Esize (T, System_Max_Binary_Modulus_Power);
19245 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
19246 Set_Is_Known_Valid (T);
19248 end Set_Modular_Size;
19250 -- Start of processing for Modular_Type_Declaration
19253 -- If the mod expression is (exactly) 2 * literal, where literal is
19254 -- 64 or less,then almost certainly the * was meant to be **. Warn.
19256 if Warn_On_Suspicious_Modulus_Value
19257 and then Nkind (Mod_Expr) = N_Op_Multiply
19258 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
19259 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
19260 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
19261 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
19264 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
19267 -- Proceed with analysis of mod expression
19269 Analyze_And_Resolve (Mod_Expr, Any_Integer);
19271 Set_Ekind (T, E_Modular_Integer_Type);
19272 Init_Alignment (T);
19273 Set_Is_Constrained (T);
19275 if not Is_OK_Static_Expression (Mod_Expr) then
19276 Flag_Non_Static_Expr
19277 ("non-static expression used for modular type bound!", Mod_Expr);
19278 M_Val := 2 ** System_Max_Binary_Modulus_Power;
19280 M_Val := Expr_Value (Mod_Expr);
19284 Error_Msg_N ("modulus value must be positive", Mod_Expr);
19285 M_Val := 2 ** System_Max_Binary_Modulus_Power;
19288 if M_Val > 2 ** Standard_Long_Integer_Size then
19289 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
19292 Set_Modulus (T, M_Val);
19294 -- Create bounds for the modular type based on the modulus given in
19295 -- the type declaration and then analyze and resolve those bounds.
19297 Set_Scalar_Range (T,
19298 Make_Range (Sloc (Mod_Expr),
19299 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
19300 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
19302 -- Properly analyze the literals for the range. We do this manually
19303 -- because we can't go calling Resolve, since we are resolving these
19304 -- bounds with the type, and this type is certainly not complete yet.
19306 Set_Etype (Low_Bound (Scalar_Range (T)), T);
19307 Set_Etype (High_Bound (Scalar_Range (T)), T);
19308 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
19309 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
19311 -- Loop through powers of two to find number of bits required
19313 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
19317 if M_Val = 2 ** Bits then
19318 Set_Modular_Size (Bits);
19323 elsif M_Val < 2 ** Bits then
19324 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
19325 Set_Non_Binary_Modulus (T);
19327 if Bits > System_Max_Nonbinary_Modulus_Power then
19328 Error_Msg_Uint_1 :=
19329 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
19331 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
19332 Set_Modular_Size (System_Max_Binary_Modulus_Power);
19336 -- In the nonbinary case, set size as per RM 13.3(55)
19338 Set_Modular_Size (Bits);
19345 -- If we fall through, then the size exceed System.Max_Binary_Modulus
19346 -- so we just signal an error and set the maximum size.
19348 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
19349 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
19351 Set_Modular_Size (System_Max_Binary_Modulus_Power);
19352 Init_Alignment (T);
19354 end Modular_Type_Declaration;
19356 --------------------------
19357 -- New_Concatenation_Op --
19358 --------------------------
19360 procedure New_Concatenation_Op (Typ : Entity_Id) is
19361 Loc : constant Source_Ptr := Sloc (Typ);
19364 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
19365 -- Create abbreviated declaration for the formal of a predefined
19366 -- Operator 'Op' of type 'Typ'
19368 --------------------
19369 -- Make_Op_Formal --
19370 --------------------
19372 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
19373 Formal : Entity_Id;
19375 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
19376 Set_Etype (Formal, Typ);
19377 Set_Mechanism (Formal, Default_Mechanism);
19379 end Make_Op_Formal;
19381 -- Start of processing for New_Concatenation_Op
19384 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
19386 Set_Ekind (Op, E_Operator);
19387 Set_Scope (Op, Current_Scope);
19388 Set_Etype (Op, Typ);
19389 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
19390 Set_Is_Immediately_Visible (Op);
19391 Set_Is_Intrinsic_Subprogram (Op);
19392 Set_Has_Completion (Op);
19393 Append_Entity (Op, Current_Scope);
19395 Set_Name_Entity_Id (Name_Op_Concat, Op);
19397 Append_Entity (Make_Op_Formal (Typ, Op), Op);
19398 Append_Entity (Make_Op_Formal (Typ, Op), Op);
19399 end New_Concatenation_Op;
19401 -------------------------
19402 -- OK_For_Limited_Init --
19403 -------------------------
19405 -- ???Check all calls of this, and compare the conditions under which it's
19408 function OK_For_Limited_Init
19410 Exp : Node_Id) return Boolean
19413 return Is_CPP_Constructor_Call (Exp)
19414 or else (Ada_Version >= Ada_2005
19415 and then not Debug_Flag_Dot_L
19416 and then OK_For_Limited_Init_In_05 (Typ, Exp));
19417 end OK_For_Limited_Init;
19419 -------------------------------
19420 -- OK_For_Limited_Init_In_05 --
19421 -------------------------------
19423 function OK_For_Limited_Init_In_05
19425 Exp : Node_Id) return Boolean
19428 -- An object of a limited interface type can be initialized with any
19429 -- expression of a nonlimited descendant type. However this does not
19430 -- apply if this is a view conversion of some other expression. This
19431 -- is checked below.
19433 if Is_Class_Wide_Type (Typ)
19434 and then Is_Limited_Interface (Typ)
19435 and then not Is_Limited_Type (Etype (Exp))
19436 and then Nkind (Exp) /= N_Type_Conversion
19441 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
19442 -- case of limited aggregates (including extension aggregates), and
19443 -- function calls. The function call may have been given in prefixed
19444 -- notation, in which case the original node is an indexed component.
19445 -- If the function is parameterless, the original node was an explicit
19446 -- dereference. The function may also be parameterless, in which case
19447 -- the source node is just an identifier.
19449 -- A branch of a conditional expression may have been removed if the
19450 -- condition is statically known. This happens during expansion, and
19451 -- thus will not happen if previous errors were encountered. The check
19452 -- will have been performed on the chosen branch, which replaces the
19453 -- original conditional expression.
19459 case Nkind (Original_Node (Exp)) is
19461 | N_Extension_Aggregate
19467 when N_Identifier =>
19468 return Present (Entity (Original_Node (Exp)))
19469 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
19471 when N_Qualified_Expression =>
19473 OK_For_Limited_Init_In_05
19474 (Typ, Expression (Original_Node (Exp)));
19476 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
19477 -- with a function call, the expander has rewritten the call into an
19478 -- N_Type_Conversion node to force displacement of the pointer to
19479 -- reference the component containing the secondary dispatch table.
19480 -- Otherwise a type conversion is not a legal context.
19481 -- A return statement for a build-in-place function returning a
19482 -- synchronized type also introduces an unchecked conversion.
19484 when N_Type_Conversion
19485 | N_Unchecked_Type_Conversion
19487 return not Comes_From_Source (Exp)
19489 OK_For_Limited_Init_In_05
19490 (Typ, Expression (Original_Node (Exp)));
19492 when N_Explicit_Dereference
19493 | N_Indexed_Component
19494 | N_Selected_Component
19496 return Nkind (Exp) = N_Function_Call;
19498 -- A use of 'Input is a function call, hence allowed. Normally the
19499 -- attribute will be changed to a call, but the attribute by itself
19500 -- can occur with -gnatc.
19502 when N_Attribute_Reference =>
19503 return Attribute_Name (Original_Node (Exp)) = Name_Input;
19505 -- "return raise ..." is OK
19507 when N_Raise_Expression =>
19510 -- For a case expression, all dependent expressions must be legal
19512 when N_Case_Expression =>
19517 Alt := First (Alternatives (Original_Node (Exp)));
19518 while Present (Alt) loop
19519 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
19529 -- For an if expression, all dependent expressions must be legal
19531 when N_If_Expression =>
19533 Then_Expr : constant Node_Id :=
19534 Next (First (Expressions (Original_Node (Exp))));
19535 Else_Expr : constant Node_Id := Next (Then_Expr);
19537 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
19539 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
19545 end OK_For_Limited_Init_In_05;
19547 -------------------------------------------
19548 -- Ordinary_Fixed_Point_Type_Declaration --
19549 -------------------------------------------
19551 procedure Ordinary_Fixed_Point_Type_Declaration
19555 Loc : constant Source_Ptr := Sloc (Def);
19556 Delta_Expr : constant Node_Id := Delta_Expression (Def);
19557 RRS : constant Node_Id := Real_Range_Specification (Def);
19558 Implicit_Base : Entity_Id;
19565 Check_Restriction (No_Fixed_Point, Def);
19567 -- Create implicit base type
19570 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
19571 Set_Etype (Implicit_Base, Implicit_Base);
19573 -- Analyze and process delta expression
19575 Analyze_And_Resolve (Delta_Expr, Any_Real);
19577 Check_Delta_Expression (Delta_Expr);
19578 Delta_Val := Expr_Value_R (Delta_Expr);
19580 Set_Delta_Value (Implicit_Base, Delta_Val);
19582 -- Compute default small from given delta, which is the largest power
19583 -- of two that does not exceed the given delta value.
19593 if Delta_Val < Ureal_1 then
19594 while Delta_Val < Tmp loop
19595 Tmp := Tmp / Ureal_2;
19596 Scale := Scale + 1;
19601 Tmp := Tmp * Ureal_2;
19602 exit when Tmp > Delta_Val;
19603 Scale := Scale - 1;
19607 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
19610 Set_Small_Value (Implicit_Base, Small_Val);
19612 -- If no range was given, set a dummy range
19614 if RRS <= Empty_Or_Error then
19615 Low_Val := -Small_Val;
19616 High_Val := Small_Val;
19618 -- Otherwise analyze and process given range
19622 Low : constant Node_Id := Low_Bound (RRS);
19623 High : constant Node_Id := High_Bound (RRS);
19626 Analyze_And_Resolve (Low, Any_Real);
19627 Analyze_And_Resolve (High, Any_Real);
19628 Check_Real_Bound (Low);
19629 Check_Real_Bound (High);
19631 -- Obtain and set the range
19633 Low_Val := Expr_Value_R (Low);
19634 High_Val := Expr_Value_R (High);
19636 if Low_Val > High_Val then
19637 Error_Msg_NE ("??fixed point type& has null range", Def, T);
19642 -- The range for both the implicit base and the declared first subtype
19643 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
19644 -- set a temporary range in place. Note that the bounds of the base
19645 -- type will be widened to be symmetrical and to fill the available
19646 -- bits when the type is frozen.
19648 -- We could do this with all discrete types, and probably should, but
19649 -- we absolutely have to do it for fixed-point, since the end-points
19650 -- of the range and the size are determined by the small value, which
19651 -- could be reset before the freeze point.
19653 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
19654 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
19656 -- Complete definition of first subtype. The inheritance of the rep item
19657 -- chain ensures that SPARK-related pragmas are not clobbered when the
19658 -- ordinary fixed point type acts as a full view of a private type.
19660 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
19661 Set_Etype (T, Implicit_Base);
19662 Init_Size_Align (T);
19663 Inherit_Rep_Item_Chain (T, Implicit_Base);
19664 Set_Small_Value (T, Small_Val);
19665 Set_Delta_Value (T, Delta_Val);
19666 Set_Is_Constrained (T);
19667 end Ordinary_Fixed_Point_Type_Declaration;
19669 ----------------------------------
19670 -- Preanalyze_Assert_Expression --
19671 ----------------------------------
19673 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
19675 In_Assertion_Expr := In_Assertion_Expr + 1;
19676 Preanalyze_Spec_Expression (N, T);
19677 In_Assertion_Expr := In_Assertion_Expr - 1;
19678 end Preanalyze_Assert_Expression;
19680 -----------------------------------
19681 -- Preanalyze_Default_Expression --
19682 -----------------------------------
19684 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
19685 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
19687 In_Default_Expr := True;
19688 Preanalyze_Spec_Expression (N, T);
19689 In_Default_Expr := Save_In_Default_Expr;
19690 end Preanalyze_Default_Expression;
19692 --------------------------------
19693 -- Preanalyze_Spec_Expression --
19694 --------------------------------
19696 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19697 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19699 In_Spec_Expression := True;
19700 Preanalyze_And_Resolve (N, T);
19701 In_Spec_Expression := Save_In_Spec_Expression;
19702 end Preanalyze_Spec_Expression;
19704 ----------------------------------------
19705 -- Prepare_Private_Subtype_Completion --
19706 ----------------------------------------
19708 procedure Prepare_Private_Subtype_Completion
19710 Related_Nod : Node_Id)
19712 Id_B : constant Entity_Id := Base_Type (Id);
19713 Full_B : Entity_Id := Full_View (Id_B);
19717 if Present (Full_B) then
19719 -- Get to the underlying full view if necessary
19721 if Is_Private_Type (Full_B)
19722 and then Present (Underlying_Full_View (Full_B))
19724 Full_B := Underlying_Full_View (Full_B);
19727 -- The Base_Type is already completed, we can complete the subtype
19728 -- now. We have to create a new entity with the same name, Thus we
19729 -- can't use Create_Itype.
19731 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
19732 Set_Is_Itype (Full);
19733 Set_Associated_Node_For_Itype (Full, Related_Nod);
19734 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
19737 -- The parent subtype may be private, but the base might not, in some
19738 -- nested instances. In that case, the subtype does not need to be
19739 -- exchanged. It would still be nice to make private subtypes and their
19740 -- bases consistent at all times ???
19742 if Is_Private_Type (Id_B) then
19743 Append_Elmt (Id, Private_Dependents (Id_B));
19745 end Prepare_Private_Subtype_Completion;
19747 ---------------------------
19748 -- Process_Discriminants --
19749 ---------------------------
19751 procedure Process_Discriminants
19753 Prev : Entity_Id := Empty)
19755 Elist : constant Elist_Id := New_Elmt_List;
19758 Discr_Number : Uint;
19759 Discr_Type : Entity_Id;
19760 Default_Present : Boolean := False;
19761 Default_Not_Present : Boolean := False;
19764 -- A composite type other than an array type can have discriminants.
19765 -- On entry, the current scope is the composite type.
19767 -- The discriminants are initially entered into the scope of the type
19768 -- via Enter_Name with the default Ekind of E_Void to prevent premature
19769 -- use, as explained at the end of this procedure.
19771 Discr := First (Discriminant_Specifications (N));
19772 while Present (Discr) loop
19773 Enter_Name (Defining_Identifier (Discr));
19775 -- For navigation purposes we add a reference to the discriminant
19776 -- in the entity for the type. If the current declaration is a
19777 -- completion, place references on the partial view. Otherwise the
19778 -- type is the current scope.
19780 if Present (Prev) then
19782 -- The references go on the partial view, if present. If the
19783 -- partial view has discriminants, the references have been
19784 -- generated already.
19786 if not Has_Discriminants (Prev) then
19787 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
19791 (Current_Scope, Defining_Identifier (Discr), 'd');
19794 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
19795 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
19797 -- Ada 2005 (AI-254)
19799 if Present (Access_To_Subprogram_Definition
19800 (Discriminant_Type (Discr)))
19801 and then Protected_Present (Access_To_Subprogram_Definition
19802 (Discriminant_Type (Discr)))
19805 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
19809 Find_Type (Discriminant_Type (Discr));
19810 Discr_Type := Etype (Discriminant_Type (Discr));
19812 if Error_Posted (Discriminant_Type (Discr)) then
19813 Discr_Type := Any_Type;
19817 -- Handling of discriminants that are access types
19819 if Is_Access_Type (Discr_Type) then
19821 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19822 -- limited record types
19824 if Ada_Version < Ada_2005 then
19825 Check_Access_Discriminant_Requires_Limited
19826 (Discr, Discriminant_Type (Discr));
19829 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19831 ("(Ada 83) access discriminant not allowed", Discr);
19834 -- If not access type, must be a discrete type
19836 elsif not Is_Discrete_Type (Discr_Type) then
19838 ("discriminants must have a discrete or access type",
19839 Discriminant_Type (Discr));
19842 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19844 -- If a discriminant specification includes the assignment compound
19845 -- delimiter followed by an expression, the expression is the default
19846 -- expression of the discriminant; the default expression must be of
19847 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19848 -- a default expression, we do the special preanalysis, since this
19849 -- expression does not freeze (see section "Handling of Default and
19850 -- Per-Object Expressions" in spec of package Sem).
19852 if Present (Expression (Discr)) then
19853 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19857 if Nkind (N) = N_Formal_Type_Declaration then
19859 ("discriminant defaults not allowed for formal type",
19860 Expression (Discr));
19862 -- Flag an error for a tagged type with defaulted discriminants,
19863 -- excluding limited tagged types when compiling for Ada 2012
19864 -- (see AI05-0214).
19866 elsif Is_Tagged_Type (Current_Scope)
19867 and then (not Is_Limited_Type (Current_Scope)
19868 or else Ada_Version < Ada_2012)
19869 and then Comes_From_Source (N)
19871 -- Note: see similar test in Check_Or_Process_Discriminants, to
19872 -- handle the (illegal) case of the completion of an untagged
19873 -- view with discriminants with defaults by a tagged full view.
19874 -- We skip the check if Discr does not come from source, to
19875 -- account for the case of an untagged derived type providing
19876 -- defaults for a renamed discriminant from a private untagged
19877 -- ancestor with a tagged full view (ACATS B460006).
19879 if Ada_Version >= Ada_2012 then
19881 ("discriminants of nonlimited tagged type cannot have"
19883 Expression (Discr));
19886 ("discriminants of tagged type cannot have defaults",
19887 Expression (Discr));
19891 Default_Present := True;
19892 Append_Elmt (Expression (Discr), Elist);
19894 -- Tag the defining identifiers for the discriminants with
19895 -- their corresponding default expressions from the tree.
19897 Set_Discriminant_Default_Value
19898 (Defining_Identifier (Discr), Expression (Discr));
19901 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19902 -- gets set unless we can be sure that no range check is required.
19904 if (GNATprove_Mode or not Expander_Active)
19907 (Expression (Discr), Discr_Type, Assume_Valid => True)
19909 Set_Do_Range_Check (Expression (Discr));
19912 -- No default discriminant value given
19915 Default_Not_Present := True;
19918 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19919 -- Discr_Type but with the null-exclusion attribute
19921 if Ada_Version >= Ada_2005 then
19923 -- Ada 2005 (AI-231): Static checks
19925 if Can_Never_Be_Null (Discr_Type) then
19926 Null_Exclusion_Static_Checks (Discr);
19928 elsif Is_Access_Type (Discr_Type)
19929 and then Null_Exclusion_Present (Discr)
19931 -- No need to check itypes because in their case this check
19932 -- was done at their point of creation
19934 and then not Is_Itype (Discr_Type)
19936 if Can_Never_Be_Null (Discr_Type) then
19938 ("`NOT NULL` not allowed (& already excludes null)",
19943 Set_Etype (Defining_Identifier (Discr),
19944 Create_Null_Excluding_Itype
19946 Related_Nod => Discr));
19948 -- Check for improper null exclusion if the type is otherwise
19949 -- legal for a discriminant.
19951 elsif Null_Exclusion_Present (Discr)
19952 and then Is_Discrete_Type (Discr_Type)
19955 ("null exclusion can only apply to an access type", Discr);
19958 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19959 -- can't have defaults. Synchronized types, or types that are
19960 -- explicitly limited are fine, but special tests apply to derived
19961 -- types in generics: in a generic body we have to assume the
19962 -- worst, and therefore defaults are not allowed if the parent is
19963 -- a generic formal private type (see ACATS B370001).
19965 if Is_Access_Type (Discr_Type) and then Default_Present then
19966 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19967 or else Is_Limited_Record (Current_Scope)
19968 or else Is_Concurrent_Type (Current_Scope)
19969 or else Is_Concurrent_Record_Type (Current_Scope)
19970 or else Ekind (Current_Scope) = E_Limited_Private_Type
19972 if not Is_Derived_Type (Current_Scope)
19973 or else not Is_Generic_Type (Etype (Current_Scope))
19974 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19975 or else Limited_Present
19976 (Type_Definition (Parent (Current_Scope)))
19982 ("access discriminants of nonlimited types cannot "
19983 & "have defaults", Expression (Discr));
19986 elsif Present (Expression (Discr)) then
19988 ("(Ada 2005) access discriminants of nonlimited types "
19989 & "cannot have defaults", Expression (Discr));
19994 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19995 -- This check is relevant only when SPARK_Mode is on as it is not a
19996 -- standard Ada legality rule.
19999 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
20001 Error_Msg_N ("discriminant cannot be volatile", Discr);
20007 -- An element list consisting of the default expressions of the
20008 -- discriminants is constructed in the above loop and used to set
20009 -- the Discriminant_Constraint attribute for the type. If an object
20010 -- is declared of this (record or task) type without any explicit
20011 -- discriminant constraint given, this element list will form the
20012 -- actual parameters for the corresponding initialization procedure
20015 Set_Discriminant_Constraint (Current_Scope, Elist);
20016 Set_Stored_Constraint (Current_Scope, No_Elist);
20018 -- Default expressions must be provided either for all or for none
20019 -- of the discriminants of a discriminant part. (RM 3.7.1)
20021 if Default_Present and then Default_Not_Present then
20023 ("incomplete specification of defaults for discriminants", N);
20026 -- The use of the name of a discriminant is not allowed in default
20027 -- expressions of a discriminant part if the specification of the
20028 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
20030 -- To detect this, the discriminant names are entered initially with an
20031 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
20032 -- attempt to use a void entity (for example in an expression that is
20033 -- type-checked) produces the error message: premature usage. Now after
20034 -- completing the semantic analysis of the discriminant part, we can set
20035 -- the Ekind of all the discriminants appropriately.
20037 Discr := First (Discriminant_Specifications (N));
20038 Discr_Number := Uint_1;
20039 while Present (Discr) loop
20040 Id := Defining_Identifier (Discr);
20041 Set_Ekind (Id, E_Discriminant);
20042 Init_Component_Location (Id);
20044 Set_Discriminant_Number (Id, Discr_Number);
20046 -- Make sure this is always set, even in illegal programs
20048 Set_Corresponding_Discriminant (Id, Empty);
20050 -- Initialize the Original_Record_Component to the entity itself.
20051 -- Inherit_Components will propagate the right value to
20052 -- discriminants in derived record types.
20054 Set_Original_Record_Component (Id, Id);
20056 -- Create the discriminal for the discriminant
20058 Build_Discriminal (Id);
20061 Discr_Number := Discr_Number + 1;
20064 Set_Has_Discriminants (Current_Scope);
20065 end Process_Discriminants;
20067 -----------------------
20068 -- Process_Full_View --
20069 -----------------------
20071 -- WARNING: This routine manages Ghost regions. Return statements must be
20072 -- replaced by gotos which jump to the end of the routine and restore the
20075 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
20076 procedure Collect_Implemented_Interfaces
20078 Ifaces : Elist_Id);
20079 -- Ada 2005: Gather all the interfaces that Typ directly or
20080 -- inherently implements. Duplicate entries are not added to
20081 -- the list Ifaces.
20083 ------------------------------------
20084 -- Collect_Implemented_Interfaces --
20085 ------------------------------------
20087 procedure Collect_Implemented_Interfaces
20092 Iface_Elmt : Elmt_Id;
20095 -- Abstract interfaces are only associated with tagged record types
20097 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
20101 -- Recursively climb to the ancestors
20103 if Etype (Typ) /= Typ
20105 -- Protect the frontend against wrong cyclic declarations like:
20107 -- type B is new A with private;
20108 -- type C is new A with private;
20110 -- type B is new C with null record;
20111 -- type C is new B with null record;
20113 and then Etype (Typ) /= Priv_T
20114 and then Etype (Typ) /= Full_T
20116 -- Keep separate the management of private type declarations
20118 if Ekind (Typ) = E_Record_Type_With_Private then
20120 -- Handle the following illegal usage:
20121 -- type Private_Type is tagged private;
20123 -- type Private_Type is new Type_Implementing_Iface;
20125 if Present (Full_View (Typ))
20126 and then Etype (Typ) /= Full_View (Typ)
20128 if Is_Interface (Etype (Typ)) then
20129 Append_Unique_Elmt (Etype (Typ), Ifaces);
20132 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
20135 -- Non-private types
20138 if Is_Interface (Etype (Typ)) then
20139 Append_Unique_Elmt (Etype (Typ), Ifaces);
20142 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
20146 -- Handle entities in the list of abstract interfaces
20148 if Present (Interfaces (Typ)) then
20149 Iface_Elmt := First_Elmt (Interfaces (Typ));
20150 while Present (Iface_Elmt) loop
20151 Iface := Node (Iface_Elmt);
20153 pragma Assert (Is_Interface (Iface));
20155 if not Contain_Interface (Iface, Ifaces) then
20156 Append_Elmt (Iface, Ifaces);
20157 Collect_Implemented_Interfaces (Iface, Ifaces);
20160 Next_Elmt (Iface_Elmt);
20163 end Collect_Implemented_Interfaces;
20167 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
20169 Full_Indic : Node_Id;
20170 Full_Parent : Entity_Id;
20171 Priv_Parent : Entity_Id;
20173 -- Start of processing for Process_Full_View
20176 Mark_And_Set_Ghost_Completion (N, Priv_T);
20178 -- First some sanity checks that must be done after semantic
20179 -- decoration of the full view and thus cannot be placed with other
20180 -- similar checks in Find_Type_Name
20182 if not Is_Limited_Type (Priv_T)
20183 and then (Is_Limited_Type (Full_T)
20184 or else Is_Limited_Composite (Full_T))
20186 if In_Instance then
20190 ("completion of nonlimited type cannot be limited", Full_T);
20191 Explain_Limited_Type (Full_T, Full_T);
20194 elsif Is_Abstract_Type (Full_T)
20195 and then not Is_Abstract_Type (Priv_T)
20198 ("completion of nonabstract type cannot be abstract", Full_T);
20200 elsif Is_Tagged_Type (Priv_T)
20201 and then Is_Limited_Type (Priv_T)
20202 and then not Is_Limited_Type (Full_T)
20204 -- If pragma CPP_Class was applied to the private declaration
20205 -- propagate the limitedness to the full-view
20207 if Is_CPP_Class (Priv_T) then
20208 Set_Is_Limited_Record (Full_T);
20210 -- GNAT allow its own definition of Limited_Controlled to disobey
20211 -- this rule in order in ease the implementation. This test is safe
20212 -- because Root_Controlled is defined in a child of System that
20213 -- normal programs are not supposed to use.
20215 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
20216 Set_Is_Limited_Composite (Full_T);
20219 ("completion of limited tagged type must be limited", Full_T);
20222 elsif Is_Generic_Type (Priv_T) then
20223 Error_Msg_N ("generic type cannot have a completion", Full_T);
20226 -- Check that ancestor interfaces of private and full views are
20227 -- consistent. We omit this check for synchronized types because
20228 -- they are performed on the corresponding record type when frozen.
20230 if Ada_Version >= Ada_2005
20231 and then Is_Tagged_Type (Priv_T)
20232 and then Is_Tagged_Type (Full_T)
20233 and then not Is_Concurrent_Type (Full_T)
20237 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
20238 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
20241 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
20242 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
20244 -- Ada 2005 (AI-251): The partial view shall be a descendant of
20245 -- an interface type if and only if the full type is descendant
20246 -- of the interface type (AARM 7.3 (7.3/2)).
20248 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
20250 if Present (Iface) then
20252 ("interface in partial view& not implemented by full type "
20253 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
20256 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
20258 if Present (Iface) then
20260 ("interface & not implemented by partial view "
20261 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
20266 if Is_Tagged_Type (Priv_T)
20267 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20268 and then Is_Derived_Type (Full_T)
20270 Priv_Parent := Etype (Priv_T);
20272 -- The full view of a private extension may have been transformed
20273 -- into an unconstrained derived type declaration and a subtype
20274 -- declaration (see build_derived_record_type for details).
20276 if Nkind (N) = N_Subtype_Declaration then
20277 Full_Indic := Subtype_Indication (N);
20278 Full_Parent := Etype (Base_Type (Full_T));
20280 Full_Indic := Subtype_Indication (Type_Definition (N));
20281 Full_Parent := Etype (Full_T);
20284 -- Check that the parent type of the full type is a descendant of
20285 -- the ancestor subtype given in the private extension. If either
20286 -- entity has an Etype equal to Any_Type then we had some previous
20287 -- error situation [7.3(8)].
20289 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
20292 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
20293 -- any order. Therefore we don't have to check that its parent must
20294 -- be a descendant of the parent of the private type declaration.
20296 elsif Is_Interface (Priv_Parent)
20297 and then Is_Interface (Full_Parent)
20301 -- Ada 2005 (AI-251): If the parent of the private type declaration
20302 -- is an interface there is no need to check that it is an ancestor
20303 -- of the associated full type declaration. The required tests for
20304 -- this case are performed by Build_Derived_Record_Type.
20306 elsif not Is_Interface (Base_Type (Priv_Parent))
20307 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
20310 ("parent of full type must descend from parent of private "
20311 & "extension", Full_Indic);
20313 -- First check a formal restriction, and then proceed with checking
20314 -- Ada rules. Since the formal restriction is not a serious error, we
20315 -- don't prevent further error detection for this check, hence the
20319 -- In formal mode, when completing a private extension the type
20320 -- named in the private part must be exactly the same as that
20321 -- named in the visible part.
20323 if Priv_Parent /= Full_Parent then
20324 Error_Msg_Name_1 := Chars (Priv_Parent);
20325 Check_SPARK_05_Restriction ("% expected", Full_Indic);
20328 -- Check the rules of 7.3(10): if the private extension inherits
20329 -- known discriminants, then the full type must also inherit those
20330 -- discriminants from the same (ancestor) type, and the parent
20331 -- subtype of the full type must be constrained if and only if
20332 -- the ancestor subtype of the private extension is constrained.
20334 if No (Discriminant_Specifications (Parent (Priv_T)))
20335 and then not Has_Unknown_Discriminants (Priv_T)
20336 and then Has_Discriminants (Base_Type (Priv_Parent))
20339 Priv_Indic : constant Node_Id :=
20340 Subtype_Indication (Parent (Priv_T));
20342 Priv_Constr : constant Boolean :=
20343 Is_Constrained (Priv_Parent)
20345 Nkind (Priv_Indic) = N_Subtype_Indication
20347 Is_Constrained (Entity (Priv_Indic));
20349 Full_Constr : constant Boolean :=
20350 Is_Constrained (Full_Parent)
20352 Nkind (Full_Indic) = N_Subtype_Indication
20354 Is_Constrained (Entity (Full_Indic));
20356 Priv_Discr : Entity_Id;
20357 Full_Discr : Entity_Id;
20360 Priv_Discr := First_Discriminant (Priv_Parent);
20361 Full_Discr := First_Discriminant (Full_Parent);
20362 while Present (Priv_Discr) and then Present (Full_Discr) loop
20363 if Original_Record_Component (Priv_Discr) =
20364 Original_Record_Component (Full_Discr)
20366 Corresponding_Discriminant (Priv_Discr) =
20367 Corresponding_Discriminant (Full_Discr)
20374 Next_Discriminant (Priv_Discr);
20375 Next_Discriminant (Full_Discr);
20378 if Present (Priv_Discr) or else Present (Full_Discr) then
20380 ("full view must inherit discriminants of the parent "
20381 & "type used in the private extension", Full_Indic);
20383 elsif Priv_Constr and then not Full_Constr then
20385 ("parent subtype of full type must be constrained",
20388 elsif Full_Constr and then not Priv_Constr then
20390 ("parent subtype of full type must be unconstrained",
20395 -- Check the rules of 7.3(12): if a partial view has neither
20396 -- known or unknown discriminants, then the full type
20397 -- declaration shall define a definite subtype.
20399 elsif not Has_Unknown_Discriminants (Priv_T)
20400 and then not Has_Discriminants (Priv_T)
20401 and then not Is_Constrained (Full_T)
20404 ("full view must define a constrained type if partial view "
20405 & "has no discriminants", Full_T);
20408 -- ??????? Do we implement the following properly ?????
20409 -- If the ancestor subtype of a private extension has constrained
20410 -- discriminants, then the parent subtype of the full view shall
20411 -- impose a statically matching constraint on those discriminants
20416 -- For untagged types, verify that a type without discriminants is
20417 -- not completed with an unconstrained type. A separate error message
20418 -- is produced if the full type has defaulted discriminants.
20420 if Is_Definite_Subtype (Priv_T)
20421 and then not Is_Definite_Subtype (Full_T)
20423 Error_Msg_Sloc := Sloc (Parent (Priv_T));
20425 ("full view of& not compatible with declaration#",
20428 if not Is_Tagged_Type (Full_T) then
20430 ("\one is constrained, the other unconstrained", Full_T);
20435 -- AI-419: verify that the use of "limited" is consistent
20438 Orig_Decl : constant Node_Id := Original_Node (N);
20441 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20442 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
20444 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
20446 if not Limited_Present (Parent (Priv_T))
20447 and then not Synchronized_Present (Parent (Priv_T))
20448 and then Limited_Present (Type_Definition (Orig_Decl))
20451 ("full view of non-limited extension cannot be limited", N);
20453 -- Conversely, if the partial view carries the limited keyword,
20454 -- the full view must as well, even if it may be redundant.
20456 elsif Limited_Present (Parent (Priv_T))
20457 and then not Limited_Present (Type_Definition (Orig_Decl))
20460 ("full view of limited extension must be explicitly limited",
20466 -- Ada 2005 (AI-443): A synchronized private extension must be
20467 -- completed by a task or protected type.
20469 if Ada_Version >= Ada_2005
20470 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20471 and then Synchronized_Present (Parent (Priv_T))
20472 and then not Is_Concurrent_Type (Full_T)
20474 Error_Msg_N ("full view of synchronized extension must " &
20475 "be synchronized type", N);
20478 -- Ada 2005 AI-363: if the full view has discriminants with
20479 -- defaults, it is illegal to declare constrained access subtypes
20480 -- whose designated type is the current type. This allows objects
20481 -- of the type that are declared in the heap to be unconstrained.
20483 if not Has_Unknown_Discriminants (Priv_T)
20484 and then not Has_Discriminants (Priv_T)
20485 and then Has_Discriminants (Full_T)
20487 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
20489 Set_Has_Constrained_Partial_View (Full_T);
20490 Set_Has_Constrained_Partial_View (Priv_T);
20493 -- Create a full declaration for all its subtypes recorded in
20494 -- Private_Dependents and swap them similarly to the base type. These
20495 -- are subtypes that have been define before the full declaration of
20496 -- the private type. We also swap the entry in Private_Dependents list
20497 -- so we can properly restore the private view on exit from the scope.
20500 Priv_Elmt : Elmt_Id;
20501 Priv_Scop : Entity_Id;
20506 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
20507 while Present (Priv_Elmt) loop
20508 Priv := Node (Priv_Elmt);
20509 Priv_Scop := Scope (Priv);
20511 if Ekind_In (Priv, E_Private_Subtype,
20512 E_Limited_Private_Subtype,
20513 E_Record_Subtype_With_Private)
20515 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
20516 Set_Is_Itype (Full);
20517 Set_Parent (Full, Parent (Priv));
20518 Set_Associated_Node_For_Itype (Full, N);
20520 -- Now we need to complete the private subtype, but since the
20521 -- base type has already been swapped, we must also swap the
20522 -- subtypes (and thus, reverse the arguments in the call to
20523 -- Complete_Private_Subtype). Also note that we may need to
20524 -- re-establish the scope of the private subtype.
20526 Copy_And_Swap (Priv, Full);
20528 if not In_Open_Scopes (Priv_Scop) then
20529 Push_Scope (Priv_Scop);
20532 -- Reset Priv_Scop to Empty to indicate no scope was pushed
20534 Priv_Scop := Empty;
20537 Complete_Private_Subtype (Full, Priv, Full_T, N);
20539 if Present (Priv_Scop) then
20543 Replace_Elmt (Priv_Elmt, Full);
20546 Next_Elmt (Priv_Elmt);
20550 -- If the private view was tagged, copy the new primitive operations
20551 -- from the private view to the full view.
20553 if Is_Tagged_Type (Full_T) then
20555 Disp_Typ : Entity_Id;
20556 Full_List : Elist_Id;
20558 Prim_Elmt : Elmt_Id;
20559 Priv_List : Elist_Id;
20563 L : Elist_Id) return Boolean;
20564 -- Determine whether list L contains element E
20572 L : Elist_Id) return Boolean
20574 List_Elmt : Elmt_Id;
20577 List_Elmt := First_Elmt (L);
20578 while Present (List_Elmt) loop
20579 if Node (List_Elmt) = E then
20583 Next_Elmt (List_Elmt);
20589 -- Start of processing
20592 if Is_Tagged_Type (Priv_T) then
20593 Priv_List := Primitive_Operations (Priv_T);
20594 Prim_Elmt := First_Elmt (Priv_List);
20596 -- In the case of a concurrent type completing a private tagged
20597 -- type, primitives may have been declared in between the two
20598 -- views. These subprograms need to be wrapped the same way
20599 -- entries and protected procedures are handled because they
20600 -- cannot be directly shared by the two views.
20602 if Is_Concurrent_Type (Full_T) then
20604 Conc_Typ : constant Entity_Id :=
20605 Corresponding_Record_Type (Full_T);
20606 Curr_Nod : Node_Id := Parent (Conc_Typ);
20607 Wrap_Spec : Node_Id;
20610 while Present (Prim_Elmt) loop
20611 Prim := Node (Prim_Elmt);
20613 if Comes_From_Source (Prim)
20614 and then not Is_Abstract_Subprogram (Prim)
20617 Make_Subprogram_Declaration (Sloc (Prim),
20621 Obj_Typ => Conc_Typ,
20623 Parameter_Specifications
20626 Insert_After (Curr_Nod, Wrap_Spec);
20627 Curr_Nod := Wrap_Spec;
20629 Analyze (Wrap_Spec);
20631 -- Remove the wrapper from visibility to avoid
20632 -- spurious conflict with the wrapped entity.
20634 Set_Is_Immediately_Visible
20635 (Defining_Entity (Specification (Wrap_Spec)),
20639 Next_Elmt (Prim_Elmt);
20645 -- For non-concurrent types, transfer explicit primitives, but
20646 -- omit those inherited from the parent of the private view
20647 -- since they will be re-inherited later on.
20650 Full_List := Primitive_Operations (Full_T);
20652 while Present (Prim_Elmt) loop
20653 Prim := Node (Prim_Elmt);
20655 if Comes_From_Source (Prim)
20656 and then not Contains (Prim, Full_List)
20658 Append_Elmt (Prim, Full_List);
20661 Next_Elmt (Prim_Elmt);
20665 -- Untagged private view
20668 Full_List := Primitive_Operations (Full_T);
20670 -- In this case the partial view is untagged, so here we locate
20671 -- all of the earlier primitives that need to be treated as
20672 -- dispatching (those that appear between the two views). Note
20673 -- that these additional operations must all be new operations
20674 -- (any earlier operations that override inherited operations
20675 -- of the full view will already have been inserted in the
20676 -- primitives list, marked by Check_Operation_From_Private_View
20677 -- as dispatching. Note that implicit "/=" operators are
20678 -- excluded from being added to the primitives list since they
20679 -- shouldn't be treated as dispatching (tagged "/=" is handled
20682 Prim := Next_Entity (Full_T);
20683 while Present (Prim) and then Prim /= Priv_T loop
20684 if Ekind_In (Prim, E_Procedure, E_Function) then
20685 Disp_Typ := Find_Dispatching_Type (Prim);
20687 if Disp_Typ = Full_T
20688 and then (Chars (Prim) /= Name_Op_Ne
20689 or else Comes_From_Source (Prim))
20691 Check_Controlling_Formals (Full_T, Prim);
20693 if not Is_Dispatching_Operation (Prim) then
20694 Append_Elmt (Prim, Full_List);
20695 Set_Is_Dispatching_Operation (Prim, True);
20696 Set_DT_Position_Value (Prim, No_Uint);
20699 elsif Is_Dispatching_Operation (Prim)
20700 and then Disp_Typ /= Full_T
20703 -- Verify that it is not otherwise controlled by a
20704 -- formal or a return value of type T.
20706 Check_Controlling_Formals (Disp_Typ, Prim);
20710 Next_Entity (Prim);
20714 -- For the tagged case, the two views can share the same primitive
20715 -- operations list and the same class-wide type. Update attributes
20716 -- of the class-wide type which depend on the full declaration.
20718 if Is_Tagged_Type (Priv_T) then
20719 Set_Direct_Primitive_Operations (Priv_T, Full_List);
20720 Set_Class_Wide_Type
20721 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
20723 Propagate_Concurrent_Flags (Class_Wide_Type (Priv_T), Full_T);
20728 -- Ada 2005 AI 161: Check preelaborable initialization consistency
20730 if Known_To_Have_Preelab_Init (Priv_T) then
20732 -- Case where there is a pragma Preelaborable_Initialization. We
20733 -- always allow this in predefined units, which is cheating a bit,
20734 -- but it means we don't have to struggle to meet the requirements in
20735 -- the RM for having Preelaborable Initialization. Otherwise we
20736 -- require that the type meets the RM rules. But we can't check that
20737 -- yet, because of the rule about overriding Initialize, so we simply
20738 -- set a flag that will be checked at freeze time.
20740 if not In_Predefined_Unit (Full_T) then
20741 Set_Must_Have_Preelab_Init (Full_T);
20745 -- If pragma CPP_Class was applied to the private type declaration,
20746 -- propagate it now to the full type declaration.
20748 if Is_CPP_Class (Priv_T) then
20749 Set_Is_CPP_Class (Full_T);
20750 Set_Convention (Full_T, Convention_CPP);
20752 -- Check that components of imported CPP types do not have default
20755 Check_CPP_Type_Has_No_Defaults (Full_T);
20758 -- If the private view has user specified stream attributes, then so has
20761 -- Why the test, how could these flags be already set in Full_T ???
20763 if Has_Specified_Stream_Read (Priv_T) then
20764 Set_Has_Specified_Stream_Read (Full_T);
20767 if Has_Specified_Stream_Write (Priv_T) then
20768 Set_Has_Specified_Stream_Write (Full_T);
20771 if Has_Specified_Stream_Input (Priv_T) then
20772 Set_Has_Specified_Stream_Input (Full_T);
20775 if Has_Specified_Stream_Output (Priv_T) then
20776 Set_Has_Specified_Stream_Output (Full_T);
20779 -- Propagate Default_Initial_Condition-related attributes from the
20780 -- partial view to the full view and its base type.
20782 Propagate_DIC_Attributes (Full_T, From_Typ => Priv_T);
20783 Propagate_DIC_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20785 -- Propagate invariant-related attributes from the partial view to the
20786 -- full view and its base type.
20788 Propagate_Invariant_Attributes (Full_T, From_Typ => Priv_T);
20789 Propagate_Invariant_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20791 -- AI12-0041: Detect an attempt to inherit a class-wide type invariant
20792 -- in the full view without advertising the inheritance in the partial
20793 -- view. This can only occur when the partial view has no parent type
20794 -- and the full view has an interface as a parent. Any other scenarios
20795 -- are illegal because implemented interfaces must match between the
20798 if Is_Tagged_Type (Priv_T) and then Is_Tagged_Type (Full_T) then
20800 Full_Par : constant Entity_Id := Etype (Full_T);
20801 Priv_Par : constant Entity_Id := Etype (Priv_T);
20804 if not Is_Interface (Priv_Par)
20805 and then Is_Interface (Full_Par)
20806 and then Has_Inheritable_Invariants (Full_Par)
20809 ("hidden inheritance of class-wide type invariants not "
20815 -- Propagate predicates to full type, and predicate function if already
20816 -- defined. It is not clear that this can actually happen? the partial
20817 -- view cannot be frozen yet, and the predicate function has not been
20818 -- built. Still it is a cheap check and seems safer to make it.
20820 if Has_Predicates (Priv_T) then
20821 Set_Has_Predicates (Full_T);
20823 if Present (Predicate_Function (Priv_T)) then
20824 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20829 Restore_Ghost_Mode (Saved_GM);
20830 end Process_Full_View;
20832 -----------------------------------
20833 -- Process_Incomplete_Dependents --
20834 -----------------------------------
20836 procedure Process_Incomplete_Dependents
20838 Full_T : Entity_Id;
20841 Inc_Elmt : Elmt_Id;
20842 Priv_Dep : Entity_Id;
20843 New_Subt : Entity_Id;
20845 Disc_Constraint : Elist_Id;
20848 if No (Private_Dependents (Inc_T)) then
20852 -- Itypes that may be generated by the completion of an incomplete
20853 -- subtype are not used by the back-end and not attached to the tree.
20854 -- They are created only for constraint-checking purposes.
20856 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20857 while Present (Inc_Elmt) loop
20858 Priv_Dep := Node (Inc_Elmt);
20860 if Ekind (Priv_Dep) = E_Subprogram_Type then
20862 -- An Access_To_Subprogram type may have a return type or a
20863 -- parameter type that is incomplete. Replace with the full view.
20865 if Etype (Priv_Dep) = Inc_T then
20866 Set_Etype (Priv_Dep, Full_T);
20870 Formal : Entity_Id;
20873 Formal := First_Formal (Priv_Dep);
20874 while Present (Formal) loop
20875 if Etype (Formal) = Inc_T then
20876 Set_Etype (Formal, Full_T);
20879 Next_Formal (Formal);
20883 elsif Is_Overloadable (Priv_Dep) then
20885 -- If a subprogram in the incomplete dependents list is primitive
20886 -- for a tagged full type then mark it as a dispatching operation,
20887 -- check whether it overrides an inherited subprogram, and check
20888 -- restrictions on its controlling formals. Note that a protected
20889 -- operation is never dispatching: only its wrapper operation
20890 -- (which has convention Ada) is.
20892 if Is_Tagged_Type (Full_T)
20893 and then Is_Primitive (Priv_Dep)
20894 and then Convention (Priv_Dep) /= Convention_Protected
20896 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20897 Set_Is_Dispatching_Operation (Priv_Dep);
20898 Check_Controlling_Formals (Full_T, Priv_Dep);
20901 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20903 -- Can happen during processing of a body before the completion
20904 -- of a TA type. Ignore, because spec is also on dependent list.
20908 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20909 -- corresponding subtype of the full view.
20911 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype
20912 and then Comes_From_Source (Priv_Dep)
20914 Set_Subtype_Indication
20915 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20916 Set_Etype (Priv_Dep, Full_T);
20917 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20918 Set_Analyzed (Parent (Priv_Dep), False);
20920 -- Reanalyze the declaration, suppressing the call to Enter_Name
20921 -- to avoid duplicate names.
20923 Analyze_Subtype_Declaration
20924 (N => Parent (Priv_Dep),
20927 -- Dependent is a subtype
20930 -- We build a new subtype indication using the full view of the
20931 -- incomplete parent. The discriminant constraints have been
20932 -- elaborated already at the point of the subtype declaration.
20934 New_Subt := Create_Itype (E_Void, N);
20936 if Has_Discriminants (Full_T) then
20937 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20939 Disc_Constraint := No_Elist;
20942 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20943 Set_Full_View (Priv_Dep, New_Subt);
20946 Next_Elmt (Inc_Elmt);
20948 end Process_Incomplete_Dependents;
20950 --------------------------------
20951 -- Process_Range_Expr_In_Decl --
20952 --------------------------------
20954 procedure Process_Range_Expr_In_Decl
20957 Subtyp : Entity_Id := Empty;
20958 Check_List : List_Id := Empty_List;
20959 R_Check_Off : Boolean := False;
20960 In_Iter_Schm : Boolean := False)
20963 R_Checks : Check_Result;
20964 Insert_Node : Node_Id;
20965 Def_Id : Entity_Id;
20968 Analyze_And_Resolve (R, Base_Type (T));
20970 if Nkind (R) = N_Range then
20972 -- In SPARK, all ranges should be static, with the exception of the
20973 -- discrete type definition of a loop parameter specification.
20975 if not In_Iter_Schm
20976 and then not Is_OK_Static_Range (R)
20978 Check_SPARK_05_Restriction ("range should be static", R);
20981 Lo := Low_Bound (R);
20982 Hi := High_Bound (R);
20984 -- Validity checks on the range of a quantified expression are
20985 -- delayed until the construct is transformed into a loop.
20987 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20988 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20992 -- We need to ensure validity of the bounds here, because if we
20993 -- go ahead and do the expansion, then the expanded code will get
20994 -- analyzed with range checks suppressed and we miss the check.
20996 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20997 -- the temporaries generated by routine Remove_Side_Effects by means
20998 -- of validity checks must use the same names. When a range appears
20999 -- in the parent of a generic, the range is processed with checks
21000 -- disabled as part of the generic context and with checks enabled
21001 -- for code generation purposes. This leads to link issues as the
21002 -- generic contains references to xxx_FIRST/_LAST, but the inlined
21003 -- template sees the temporaries generated by Remove_Side_Effects.
21006 Validity_Check_Range (R, Subtyp);
21009 -- If there were errors in the declaration, try and patch up some
21010 -- common mistakes in the bounds. The cases handled are literals
21011 -- which are Integer where the expected type is Real and vice versa.
21012 -- These corrections allow the compilation process to proceed further
21013 -- along since some basic assumptions of the format of the bounds
21016 if Etype (R) = Any_Type then
21017 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
21019 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
21021 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
21023 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
21025 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
21027 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
21029 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
21031 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
21038 -- If the bounds of the range have been mistakenly given as string
21039 -- literals (perhaps in place of character literals), then an error
21040 -- has already been reported, but we rewrite the string literal as a
21041 -- bound of the range's type to avoid blowups in later processing
21042 -- that looks at static values.
21044 if Nkind (Lo) = N_String_Literal then
21046 Make_Attribute_Reference (Sloc (Lo),
21047 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
21048 Attribute_Name => Name_First));
21049 Analyze_And_Resolve (Lo);
21052 if Nkind (Hi) = N_String_Literal then
21054 Make_Attribute_Reference (Sloc (Hi),
21055 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
21056 Attribute_Name => Name_First));
21057 Analyze_And_Resolve (Hi);
21060 -- If bounds aren't scalar at this point then exit, avoiding
21061 -- problems with further processing of the range in this procedure.
21063 if not Is_Scalar_Type (Etype (Lo)) then
21067 -- Resolve (actually Sem_Eval) has checked that the bounds are in
21068 -- then range of the base type. Here we check whether the bounds
21069 -- are in the range of the subtype itself. Note that if the bounds
21070 -- represent the null range the Constraint_Error exception should
21073 -- ??? The following code should be cleaned up as follows
21075 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
21076 -- is done in the call to Range_Check (R, T); below
21078 -- 2. The use of R_Check_Off should be investigated and possibly
21079 -- removed, this would clean up things a bit.
21081 if Is_Null_Range (Lo, Hi) then
21085 -- Capture values of bounds and generate temporaries for them
21086 -- if needed, before applying checks, since checks may cause
21087 -- duplication of the expression without forcing evaluation.
21089 -- The forced evaluation removes side effects from expressions,
21090 -- which should occur also in GNATprove mode. Otherwise, we end up
21091 -- with unexpected insertions of actions at places where this is
21092 -- not supposed to occur, e.g. on default parameters of a call.
21094 if Expander_Active or GNATprove_Mode then
21096 -- Call Force_Evaluation to create declarations as needed to
21097 -- deal with side effects, and also create typ_FIRST/LAST
21098 -- entities for bounds if we have a subtype name.
21100 -- Note: we do this transformation even if expansion is not
21101 -- active if we are in GNATprove_Mode since the transformation
21102 -- is in general required to ensure that the resulting tree has
21103 -- proper Ada semantics.
21106 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
21108 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
21111 -- We use a flag here instead of suppressing checks on the type
21112 -- because the type we check against isn't necessarily the place
21113 -- where we put the check.
21115 if not R_Check_Off then
21116 R_Checks := Get_Range_Checks (R, T);
21118 -- Look up tree to find an appropriate insertion point. We
21119 -- can't just use insert_actions because later processing
21120 -- depends on the insertion node. Prior to Ada 2012 the
21121 -- insertion point could only be a declaration or a loop, but
21122 -- quantified expressions can appear within any context in an
21123 -- expression, and the insertion point can be any statement,
21124 -- pragma, or declaration.
21126 Insert_Node := Parent (R);
21127 while Present (Insert_Node) loop
21129 Nkind (Insert_Node) in N_Declaration
21132 (Insert_Node, N_Component_Declaration,
21133 N_Loop_Parameter_Specification,
21134 N_Function_Specification,
21135 N_Procedure_Specification);
21137 exit when Nkind (Insert_Node) in N_Later_Decl_Item
21138 or else Nkind (Insert_Node) in
21139 N_Statement_Other_Than_Procedure_Call
21140 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
21143 Insert_Node := Parent (Insert_Node);
21146 -- Why would Type_Decl not be present??? Without this test,
21147 -- short regression tests fail.
21149 if Present (Insert_Node) then
21151 -- Case of loop statement. Verify that the range is part
21152 -- of the subtype indication of the iteration scheme.
21154 if Nkind (Insert_Node) = N_Loop_Statement then
21159 Indic := Parent (R);
21160 while Present (Indic)
21161 and then Nkind (Indic) /= N_Subtype_Indication
21163 Indic := Parent (Indic);
21166 if Present (Indic) then
21167 Def_Id := Etype (Subtype_Mark (Indic));
21169 Insert_Range_Checks
21173 Sloc (Insert_Node),
21175 Do_Before => True);
21179 -- Insertion before a declaration. If the declaration
21180 -- includes discriminants, the list of applicable checks
21181 -- is given by the caller.
21183 elsif Nkind (Insert_Node) in N_Declaration then
21184 Def_Id := Defining_Identifier (Insert_Node);
21186 if (Ekind (Def_Id) = E_Record_Type
21187 and then Depends_On_Discriminant (R))
21189 (Ekind (Def_Id) = E_Protected_Type
21190 and then Has_Discriminants (Def_Id))
21192 Append_Range_Checks
21194 Check_List, Def_Id, Sloc (Insert_Node), R);
21197 Insert_Range_Checks
21199 Insert_Node, Def_Id, Sloc (Insert_Node), R);
21203 -- Insertion before a statement. Range appears in the
21204 -- context of a quantified expression. Insertion will
21205 -- take place when expression is expanded.
21214 -- Case of other than an explicit N_Range node
21216 -- The forced evaluation removes side effects from expressions, which
21217 -- should occur also in GNATprove mode. Otherwise, we end up with
21218 -- unexpected insertions of actions at places where this is not
21219 -- supposed to occur, e.g. on default parameters of a call.
21221 elsif Expander_Active or GNATprove_Mode then
21222 Get_Index_Bounds (R, Lo, Hi);
21223 Force_Evaluation (Lo);
21224 Force_Evaluation (Hi);
21226 end Process_Range_Expr_In_Decl;
21228 --------------------------------------
21229 -- Process_Real_Range_Specification --
21230 --------------------------------------
21232 procedure Process_Real_Range_Specification (Def : Node_Id) is
21233 Spec : constant Node_Id := Real_Range_Specification (Def);
21236 Err : Boolean := False;
21238 procedure Analyze_Bound (N : Node_Id);
21239 -- Analyze and check one bound
21241 -------------------
21242 -- Analyze_Bound --
21243 -------------------
21245 procedure Analyze_Bound (N : Node_Id) is
21247 Analyze_And_Resolve (N, Any_Real);
21249 if not Is_OK_Static_Expression (N) then
21250 Flag_Non_Static_Expr
21251 ("bound in real type definition is not static!", N);
21256 -- Start of processing for Process_Real_Range_Specification
21259 if Present (Spec) then
21260 Lo := Low_Bound (Spec);
21261 Hi := High_Bound (Spec);
21262 Analyze_Bound (Lo);
21263 Analyze_Bound (Hi);
21265 -- If error, clear away junk range specification
21268 Set_Real_Range_Specification (Def, Empty);
21271 end Process_Real_Range_Specification;
21273 ---------------------
21274 -- Process_Subtype --
21275 ---------------------
21277 function Process_Subtype
21279 Related_Nod : Node_Id;
21280 Related_Id : Entity_Id := Empty;
21281 Suffix : Character := ' ') return Entity_Id
21284 Def_Id : Entity_Id;
21285 Error_Node : Node_Id;
21286 Full_View_Id : Entity_Id;
21287 Subtype_Mark_Id : Entity_Id;
21289 May_Have_Null_Exclusion : Boolean;
21291 procedure Check_Incomplete (T : Node_Id);
21292 -- Called to verify that an incomplete type is not used prematurely
21294 ----------------------
21295 -- Check_Incomplete --
21296 ----------------------
21298 procedure Check_Incomplete (T : Node_Id) is
21300 -- Ada 2005 (AI-412): Incomplete subtypes are legal
21302 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
21304 not (Ada_Version >= Ada_2005
21306 (Nkind (Parent (T)) = N_Subtype_Declaration
21307 or else (Nkind (Parent (T)) = N_Subtype_Indication
21308 and then Nkind (Parent (Parent (T))) =
21309 N_Subtype_Declaration)))
21311 Error_Msg_N ("invalid use of type before its full declaration", T);
21313 end Check_Incomplete;
21315 -- Start of processing for Process_Subtype
21318 -- Case of no constraints present
21320 if Nkind (S) /= N_Subtype_Indication then
21322 Check_Incomplete (S);
21325 -- Ada 2005 (AI-231): Static check
21327 if Ada_Version >= Ada_2005
21328 and then Present (P)
21329 and then Null_Exclusion_Present (P)
21330 and then Nkind (P) /= N_Access_To_Object_Definition
21331 and then not Is_Access_Type (Entity (S))
21333 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
21336 -- The following is ugly, can't we have a range or even a flag???
21338 May_Have_Null_Exclusion :=
21339 Nkind_In (P, N_Access_Definition,
21340 N_Access_Function_Definition,
21341 N_Access_Procedure_Definition,
21342 N_Access_To_Object_Definition,
21344 N_Component_Definition)
21346 Nkind_In (P, N_Derived_Type_Definition,
21347 N_Discriminant_Specification,
21348 N_Formal_Object_Declaration,
21349 N_Object_Declaration,
21350 N_Object_Renaming_Declaration,
21351 N_Parameter_Specification,
21352 N_Subtype_Declaration);
21354 -- Create an Itype that is a duplicate of Entity (S) but with the
21355 -- null-exclusion attribute.
21357 if May_Have_Null_Exclusion
21358 and then Is_Access_Type (Entity (S))
21359 and then Null_Exclusion_Present (P)
21361 -- No need to check the case of an access to object definition.
21362 -- It is correct to define double not-null pointers.
21365 -- type Not_Null_Int_Ptr is not null access Integer;
21366 -- type Acc is not null access Not_Null_Int_Ptr;
21368 and then Nkind (P) /= N_Access_To_Object_Definition
21370 if Can_Never_Be_Null (Entity (S)) then
21371 case Nkind (Related_Nod) is
21372 when N_Full_Type_Declaration =>
21373 if Nkind (Type_Definition (Related_Nod))
21374 in N_Array_Type_Definition
21378 (Component_Definition
21379 (Type_Definition (Related_Nod)));
21382 Subtype_Indication (Type_Definition (Related_Nod));
21385 when N_Subtype_Declaration =>
21386 Error_Node := Subtype_Indication (Related_Nod);
21388 when N_Object_Declaration =>
21389 Error_Node := Object_Definition (Related_Nod);
21391 when N_Component_Declaration =>
21393 Subtype_Indication (Component_Definition (Related_Nod));
21395 when N_Allocator =>
21396 Error_Node := Expression (Related_Nod);
21399 pragma Assert (False);
21400 Error_Node := Related_Nod;
21404 ("`NOT NULL` not allowed (& already excludes null)",
21410 Create_Null_Excluding_Itype
21412 Related_Nod => P));
21413 Set_Entity (S, Etype (S));
21418 -- Case of constraint present, so that we have an N_Subtype_Indication
21419 -- node (this node is created only if constraints are present).
21422 Find_Type (Subtype_Mark (S));
21424 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
21426 (Nkind (Parent (S)) = N_Subtype_Declaration
21427 and then Is_Itype (Defining_Identifier (Parent (S))))
21429 Check_Incomplete (Subtype_Mark (S));
21433 Subtype_Mark_Id := Entity (Subtype_Mark (S));
21435 -- Explicit subtype declaration case
21437 if Nkind (P) = N_Subtype_Declaration then
21438 Def_Id := Defining_Identifier (P);
21440 -- Explicit derived type definition case
21442 elsif Nkind (P) = N_Derived_Type_Definition then
21443 Def_Id := Defining_Identifier (Parent (P));
21445 -- Implicit case, the Def_Id must be created as an implicit type.
21446 -- The one exception arises in the case of concurrent types, array
21447 -- and access types, where other subsidiary implicit types may be
21448 -- created and must appear before the main implicit type. In these
21449 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
21450 -- has not yet been called to create Def_Id.
21453 if Is_Array_Type (Subtype_Mark_Id)
21454 or else Is_Concurrent_Type (Subtype_Mark_Id)
21455 or else Is_Access_Type (Subtype_Mark_Id)
21459 -- For the other cases, we create a new unattached Itype,
21460 -- and set the indication to ensure it gets attached later.
21464 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21468 -- If the kind of constraint is invalid for this kind of type,
21469 -- then give an error, and then pretend no constraint was given.
21471 if not Is_Valid_Constraint_Kind
21472 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
21475 ("incorrect constraint for this kind of type", Constraint (S));
21477 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
21479 -- Set Ekind of orphan itype, to prevent cascaded errors
21481 if Present (Def_Id) then
21482 Set_Ekind (Def_Id, Ekind (Any_Type));
21485 -- Make recursive call, having got rid of the bogus constraint
21487 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
21490 -- Remaining processing depends on type. Select on Base_Type kind to
21491 -- ensure getting to the concrete type kind in the case of a private
21492 -- subtype (needed when only doing semantic analysis).
21494 case Ekind (Base_Type (Subtype_Mark_Id)) is
21495 when Access_Kind =>
21497 -- If this is a constraint on a class-wide type, discard it.
21498 -- There is currently no way to express a partial discriminant
21499 -- constraint on a type with unknown discriminants. This is
21500 -- a pathology that the ACATS wisely decides not to test.
21502 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
21503 if Comes_From_Source (S) then
21505 ("constraint on class-wide type ignored??",
21509 if Nkind (P) = N_Subtype_Declaration then
21510 Set_Subtype_Indication (P,
21511 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
21514 return Subtype_Mark_Id;
21517 Constrain_Access (Def_Id, S, Related_Nod);
21520 and then Is_Itype (Designated_Type (Def_Id))
21521 and then Nkind (Related_Nod) = N_Subtype_Declaration
21522 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
21524 Build_Itype_Reference
21525 (Designated_Type (Def_Id), Related_Nod);
21529 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
21531 when Decimal_Fixed_Point_Kind =>
21532 Constrain_Decimal (Def_Id, S);
21534 when Enumeration_Kind =>
21535 Constrain_Enumeration (Def_Id, S);
21536 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21538 when Ordinary_Fixed_Point_Kind =>
21539 Constrain_Ordinary_Fixed (Def_Id, S);
21542 Constrain_Float (Def_Id, S);
21544 when Integer_Kind =>
21545 Constrain_Integer (Def_Id, S);
21546 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21548 when Class_Wide_Kind
21549 | E_Incomplete_Type
21553 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21555 if Ekind (Def_Id) = E_Incomplete_Type then
21556 Set_Private_Dependents (Def_Id, New_Elmt_List);
21559 when Private_Kind =>
21560 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21562 -- The base type may be private but Def_Id may be a full view
21565 if Is_Private_Type (Def_Id) then
21566 Set_Private_Dependents (Def_Id, New_Elmt_List);
21569 -- In case of an invalid constraint prevent further processing
21570 -- since the type constructed is missing expected fields.
21572 if Etype (Def_Id) = Any_Type then
21576 -- If the full view is that of a task with discriminants,
21577 -- we must constrain both the concurrent type and its
21578 -- corresponding record type. Otherwise we will just propagate
21579 -- the constraint to the full view, if available.
21581 if Present (Full_View (Subtype_Mark_Id))
21582 and then Has_Discriminants (Subtype_Mark_Id)
21583 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
21586 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21588 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
21589 Constrain_Concurrent (Full_View_Id, S,
21590 Related_Nod, Related_Id, Suffix);
21591 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
21592 Set_Full_View (Def_Id, Full_View_Id);
21594 -- Introduce an explicit reference to the private subtype,
21595 -- to prevent scope anomalies in gigi if first use appears
21596 -- in a nested context, e.g. a later function body.
21597 -- Should this be generated in other contexts than a full
21598 -- type declaration?
21600 if Is_Itype (Def_Id)
21602 Nkind (Parent (P)) = N_Full_Type_Declaration
21604 Build_Itype_Reference (Def_Id, Parent (P));
21608 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
21611 when Concurrent_Kind =>
21612 Constrain_Concurrent (Def_Id, S,
21613 Related_Nod, Related_Id, Suffix);
21616 Error_Msg_N ("invalid subtype mark in subtype indication", S);
21619 -- Size, Alignment, Representation aspects and Convention are always
21620 -- inherited from the base type.
21622 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
21623 Set_Rep_Info (Def_Id, (Subtype_Mark_Id));
21624 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
21628 end Process_Subtype;
21630 -----------------------------
21631 -- Record_Type_Declaration --
21632 -----------------------------
21634 procedure Record_Type_Declaration
21639 Def : constant Node_Id := Type_Definition (N);
21640 Is_Tagged : Boolean;
21641 Tag_Comp : Entity_Id;
21644 -- These flags must be initialized before calling Process_Discriminants
21645 -- because this routine makes use of them.
21647 Set_Ekind (T, E_Record_Type);
21649 Init_Size_Align (T);
21650 Set_Interfaces (T, No_Elist);
21651 Set_Stored_Constraint (T, No_Elist);
21652 Set_Default_SSO (T);
21653 Set_No_Reordering (T, No_Component_Reordering);
21657 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
21658 if Limited_Present (Def) then
21659 Check_SPARK_05_Restriction ("limited is not allowed", N);
21662 if Abstract_Present (Def) then
21663 Check_SPARK_05_Restriction ("abstract is not allowed", N);
21666 -- The flag Is_Tagged_Type might have already been set by
21667 -- Find_Type_Name if it detected an error for declaration T. This
21668 -- arises in the case of private tagged types where the full view
21669 -- omits the word tagged.
21672 Tagged_Present (Def)
21673 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21675 Set_Is_Limited_Record (T, Limited_Present (Def));
21678 Set_Is_Tagged_Type (T, True);
21679 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21682 -- Type is abstract if full declaration carries keyword, or if
21683 -- previous partial view did.
21685 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21686 or else Abstract_Present (Def));
21689 Check_SPARK_05_Restriction ("interface is not allowed", N);
21692 Analyze_Interface_Declaration (T, Def);
21694 if Present (Discriminant_Specifications (N)) then
21696 ("interface types cannot have discriminants",
21697 Defining_Identifier
21698 (First (Discriminant_Specifications (N))));
21702 -- First pass: if there are self-referential access components,
21703 -- create the required anonymous access type declarations, and if
21704 -- need be an incomplete type declaration for T itself.
21706 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21708 if Ada_Version >= Ada_2005
21709 and then Present (Interface_List (Def))
21711 Check_Interfaces (N, Def);
21714 Ifaces_List : Elist_Id;
21717 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21718 -- already in the parents.
21722 Ifaces_List => Ifaces_List,
21723 Exclude_Parents => True);
21725 Set_Interfaces (T, Ifaces_List);
21729 -- Records constitute a scope for the component declarations within.
21730 -- The scope is created prior to the processing of these declarations.
21731 -- Discriminants are processed first, so that they are visible when
21732 -- processing the other components. The Ekind of the record type itself
21733 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21735 -- Enter record scope
21739 -- If an incomplete or private type declaration was already given for
21740 -- the type, then this scope already exists, and the discriminants have
21741 -- been declared within. We must verify that the full declaration
21742 -- matches the incomplete one.
21744 Check_Or_Process_Discriminants (N, T, Prev);
21746 Set_Is_Constrained (T, not Has_Discriminants (T));
21747 Set_Has_Delayed_Freeze (T, True);
21749 -- For tagged types add a manually analyzed component corresponding
21750 -- to the component _tag, the corresponding piece of tree will be
21751 -- expanded as part of the freezing actions if it is not a CPP_Class.
21755 -- Do not add the tag unless we are in expansion mode
21757 if Expander_Active then
21758 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21759 Enter_Name (Tag_Comp);
21761 Set_Ekind (Tag_Comp, E_Component);
21762 Set_Is_Tag (Tag_Comp);
21763 Set_Is_Aliased (Tag_Comp);
21764 Set_Etype (Tag_Comp, RTE (RE_Tag));
21765 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21766 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21767 Init_Component_Location (Tag_Comp);
21769 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21770 -- implemented interfaces.
21772 if Has_Interfaces (T) then
21773 Add_Interface_Tag_Components (N, T);
21777 Make_Class_Wide_Type (T);
21778 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21781 -- We must suppress range checks when processing record components in
21782 -- the presence of discriminants, since we don't want spurious checks to
21783 -- be generated during their analysis, but Suppress_Range_Checks flags
21784 -- must be reset the after processing the record definition.
21786 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21787 -- couldn't we just use the normal range check suppression method here.
21788 -- That would seem cleaner ???
21790 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21791 Set_Kill_Range_Checks (T, True);
21792 Record_Type_Definition (Def, Prev);
21793 Set_Kill_Range_Checks (T, False);
21795 Record_Type_Definition (Def, Prev);
21798 -- Exit from record scope
21802 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21803 -- the implemented interfaces and associate them an aliased entity.
21806 and then not Is_Empty_List (Interface_List (Def))
21808 Derive_Progenitor_Subprograms (T, T);
21811 Check_Function_Writable_Actuals (N);
21812 end Record_Type_Declaration;
21814 ----------------------------
21815 -- Record_Type_Definition --
21816 ----------------------------
21818 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21819 Component : Entity_Id;
21820 Ctrl_Components : Boolean := False;
21821 Final_Storage_Only : Boolean;
21825 if Ekind (Prev_T) = E_Incomplete_Type then
21826 T := Full_View (Prev_T);
21831 -- In SPARK, tagged types and type extensions may only be declared in
21832 -- the specification of library unit packages.
21834 if Present (Def) and then Is_Tagged_Type (T) then
21840 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21841 Typ := Parent (Def);
21844 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21845 Typ := Parent (Parent (Def));
21848 Ctxt := Parent (Typ);
21850 if Nkind (Ctxt) = N_Package_Body
21851 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21853 Check_SPARK_05_Restriction
21854 ("type should be defined in package specification", Typ);
21856 elsif Nkind (Ctxt) /= N_Package_Specification
21857 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21859 Check_SPARK_05_Restriction
21860 ("type should be defined in library unit package", Typ);
21865 Final_Storage_Only := not Is_Controlled (T);
21867 -- Ada 2005: Check whether an explicit Limited is present in a derived
21868 -- type declaration.
21870 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21871 and then Limited_Present (Parent (Def))
21873 Set_Is_Limited_Record (T);
21876 -- If the component list of a record type is defined by the reserved
21877 -- word null and there is no discriminant part, then the record type has
21878 -- no components and all records of the type are null records (RM 3.7)
21879 -- This procedure is also called to process the extension part of a
21880 -- record extension, in which case the current scope may have inherited
21884 or else No (Component_List (Def))
21885 or else Null_Present (Component_List (Def))
21887 if not Is_Tagged_Type (T) then
21888 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21892 Analyze_Declarations (Component_Items (Component_List (Def)));
21894 if Present (Variant_Part (Component_List (Def))) then
21895 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21896 Analyze (Variant_Part (Component_List (Def)));
21900 -- After completing the semantic analysis of the record definition,
21901 -- record components, both new and inherited, are accessible. Set their
21902 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21903 -- whose Ekind may be void.
21905 Component := First_Entity (Current_Scope);
21906 while Present (Component) loop
21907 if Ekind (Component) = E_Void
21908 and then not Is_Itype (Component)
21910 Set_Ekind (Component, E_Component);
21911 Init_Component_Location (Component);
21914 Propagate_Concurrent_Flags (T, Etype (Component));
21916 if Ekind (Component) /= E_Component then
21919 -- Do not set Has_Controlled_Component on a class-wide equivalent
21920 -- type. See Make_CW_Equivalent_Type.
21922 elsif not Is_Class_Wide_Equivalent_Type (T)
21923 and then (Has_Controlled_Component (Etype (Component))
21924 or else (Chars (Component) /= Name_uParent
21925 and then Is_Controlled (Etype (Component))))
21927 Set_Has_Controlled_Component (T, True);
21928 Final_Storage_Only :=
21930 and then Finalize_Storage_Only (Etype (Component));
21931 Ctrl_Components := True;
21934 Next_Entity (Component);
21937 -- A Type is Finalize_Storage_Only only if all its controlled components
21940 if Ctrl_Components then
21941 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21944 -- Place reference to end record on the proper entity, which may
21945 -- be a partial view.
21947 if Present (Def) then
21948 Process_End_Label (Def, 'e', Prev_T);
21950 end Record_Type_Definition;
21952 ------------------------
21953 -- Replace_Components --
21954 ------------------------
21956 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21957 function Process (N : Node_Id) return Traverse_Result;
21963 function Process (N : Node_Id) return Traverse_Result is
21967 if Nkind (N) = N_Discriminant_Specification then
21968 Comp := First_Discriminant (Typ);
21969 while Present (Comp) loop
21970 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21971 Set_Defining_Identifier (N, Comp);
21975 Next_Discriminant (Comp);
21978 elsif Nkind (N) = N_Variant_Part then
21979 Comp := First_Discriminant (Typ);
21980 while Present (Comp) loop
21981 if Chars (Comp) = Chars (Name (N)) then
21982 Set_Entity (Name (N), Comp);
21986 Next_Component (Comp);
21989 elsif Nkind (N) = N_Component_Declaration then
21990 Comp := First_Component (Typ);
21991 while Present (Comp) loop
21992 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21993 Set_Defining_Identifier (N, Comp);
21997 Next_Component (Comp);
22004 procedure Replace is new Traverse_Proc (Process);
22006 -- Start of processing for Replace_Components
22010 end Replace_Components;
22012 -------------------------------
22013 -- Set_Completion_Referenced --
22014 -------------------------------
22016 procedure Set_Completion_Referenced (E : Entity_Id) is
22018 -- If in main unit, mark entity that is a completion as referenced,
22019 -- warnings go on the partial view when needed.
22021 if In_Extended_Main_Source_Unit (E) then
22022 Set_Referenced (E);
22024 end Set_Completion_Referenced;
22026 ---------------------
22027 -- Set_Default_SSO --
22028 ---------------------
22030 procedure Set_Default_SSO (T : Entity_Id) is
22032 case Opt.Default_SSO is
22036 Set_SSO_Set_Low_By_Default (T, True);
22038 Set_SSO_Set_High_By_Default (T, True);
22040 raise Program_Error;
22042 end Set_Default_SSO;
22044 ---------------------
22045 -- Set_Fixed_Range --
22046 ---------------------
22048 -- The range for fixed-point types is complicated by the fact that we
22049 -- do not know the exact end points at the time of the declaration. This
22050 -- is true for three reasons:
22052 -- A size clause may affect the fudging of the end-points.
22053 -- A small clause may affect the values of the end-points.
22054 -- We try to include the end-points if it does not affect the size.
22056 -- This means that the actual end-points must be established at the
22057 -- point when the type is frozen. Meanwhile, we first narrow the range
22058 -- as permitted (so that it will fit if necessary in a small specified
22059 -- size), and then build a range subtree with these narrowed bounds.
22060 -- Set_Fixed_Range constructs the range from real literal values, and
22061 -- sets the range as the Scalar_Range of the given fixed-point type entity.
22063 -- The parent of this range is set to point to the entity so that it is
22064 -- properly hooked into the tree (unlike normal Scalar_Range entries for
22065 -- other scalar types, which are just pointers to the range in the
22066 -- original tree, this would otherwise be an orphan).
22068 -- The tree is left unanalyzed. When the type is frozen, the processing
22069 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
22070 -- analyzed, and uses this as an indication that it should complete
22071 -- work on the range (it will know the final small and size values).
22073 procedure Set_Fixed_Range
22079 S : constant Node_Id :=
22081 Low_Bound => Make_Real_Literal (Loc, Lo),
22082 High_Bound => Make_Real_Literal (Loc, Hi));
22084 Set_Scalar_Range (E, S);
22087 -- Before the freeze point, the bounds of a fixed point are universal
22088 -- and carry the corresponding type.
22090 Set_Etype (Low_Bound (S), Universal_Real);
22091 Set_Etype (High_Bound (S), Universal_Real);
22092 end Set_Fixed_Range;
22094 ----------------------------------
22095 -- Set_Scalar_Range_For_Subtype --
22096 ----------------------------------
22098 procedure Set_Scalar_Range_For_Subtype
22099 (Def_Id : Entity_Id;
22103 Kind : constant Entity_Kind := Ekind (Def_Id);
22106 -- Defend against previous error
22108 if Nkind (R) = N_Error then
22112 Set_Scalar_Range (Def_Id, R);
22114 -- We need to link the range into the tree before resolving it so
22115 -- that types that are referenced, including importantly the subtype
22116 -- itself, are properly frozen (Freeze_Expression requires that the
22117 -- expression be properly linked into the tree). Of course if it is
22118 -- already linked in, then we do not disturb the current link.
22120 if No (Parent (R)) then
22121 Set_Parent (R, Def_Id);
22124 -- Reset the kind of the subtype during analysis of the range, to
22125 -- catch possible premature use in the bounds themselves.
22127 Set_Ekind (Def_Id, E_Void);
22128 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
22129 Set_Ekind (Def_Id, Kind);
22130 end Set_Scalar_Range_For_Subtype;
22132 --------------------------------------------------------
22133 -- Set_Stored_Constraint_From_Discriminant_Constraint --
22134 --------------------------------------------------------
22136 procedure Set_Stored_Constraint_From_Discriminant_Constraint
22140 -- Make sure set if encountered during Expand_To_Stored_Constraint
22142 Set_Stored_Constraint (E, No_Elist);
22144 -- Give it the right value
22146 if Is_Constrained (E) and then Has_Discriminants (E) then
22147 Set_Stored_Constraint (E,
22148 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
22150 end Set_Stored_Constraint_From_Discriminant_Constraint;
22152 -------------------------------------
22153 -- Signed_Integer_Type_Declaration --
22154 -------------------------------------
22156 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
22157 Implicit_Base : Entity_Id;
22158 Base_Typ : Entity_Id;
22161 Errs : Boolean := False;
22165 function Can_Derive_From (E : Entity_Id) return Boolean;
22166 -- Determine whether given bounds allow derivation from specified type
22168 procedure Check_Bound (Expr : Node_Id);
22169 -- Check bound to make sure it is integral and static. If not, post
22170 -- appropriate error message and set Errs flag
22172 ---------------------
22173 -- Can_Derive_From --
22174 ---------------------
22176 -- Note we check both bounds against both end values, to deal with
22177 -- strange types like ones with a range of 0 .. -12341234.
22179 function Can_Derive_From (E : Entity_Id) return Boolean is
22180 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
22181 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
22183 return Lo <= Lo_Val and then Lo_Val <= Hi
22185 Lo <= Hi_Val and then Hi_Val <= Hi;
22186 end Can_Derive_From;
22192 procedure Check_Bound (Expr : Node_Id) is
22194 -- If a range constraint is used as an integer type definition, each
22195 -- bound of the range must be defined by a static expression of some
22196 -- integer type, but the two bounds need not have the same integer
22197 -- type (Negative bounds are allowed.) (RM 3.5.4)
22199 if not Is_Integer_Type (Etype (Expr)) then
22201 ("integer type definition bounds must be of integer type", Expr);
22204 elsif not Is_OK_Static_Expression (Expr) then
22205 Flag_Non_Static_Expr
22206 ("non-static expression used for integer type bound!", Expr);
22209 -- The bounds are folded into literals, and we set their type to be
22210 -- universal, to avoid typing difficulties: we cannot set the type
22211 -- of the literal to the new type, because this would be a forward
22212 -- reference for the back end, and if the original type is user-
22213 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
22216 if Is_Entity_Name (Expr) then
22217 Fold_Uint (Expr, Expr_Value (Expr), True);
22220 Set_Etype (Expr, Universal_Integer);
22224 -- Start of processing for Signed_Integer_Type_Declaration
22227 -- Create an anonymous base type
22230 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
22232 -- Analyze and check the bounds, they can be of any integer type
22234 Lo := Low_Bound (Def);
22235 Hi := High_Bound (Def);
22237 -- Arbitrarily use Integer as the type if either bound had an error
22239 if Hi = Error or else Lo = Error then
22240 Base_Typ := Any_Integer;
22241 Set_Error_Posted (T, True);
22243 -- Here both bounds are OK expressions
22246 Analyze_And_Resolve (Lo, Any_Integer);
22247 Analyze_And_Resolve (Hi, Any_Integer);
22253 Hi := Type_High_Bound (Standard_Long_Long_Integer);
22254 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
22257 -- Find type to derive from
22259 Lo_Val := Expr_Value (Lo);
22260 Hi_Val := Expr_Value (Hi);
22262 if Can_Derive_From (Standard_Short_Short_Integer) then
22263 Base_Typ := Base_Type (Standard_Short_Short_Integer);
22265 elsif Can_Derive_From (Standard_Short_Integer) then
22266 Base_Typ := Base_Type (Standard_Short_Integer);
22268 elsif Can_Derive_From (Standard_Integer) then
22269 Base_Typ := Base_Type (Standard_Integer);
22271 elsif Can_Derive_From (Standard_Long_Integer) then
22272 Base_Typ := Base_Type (Standard_Long_Integer);
22274 elsif Can_Derive_From (Standard_Long_Long_Integer) then
22275 Check_Restriction (No_Long_Long_Integers, Def);
22276 Base_Typ := Base_Type (Standard_Long_Long_Integer);
22279 Base_Typ := Base_Type (Standard_Long_Long_Integer);
22280 Error_Msg_N ("integer type definition bounds out of range", Def);
22281 Hi := Type_High_Bound (Standard_Long_Long_Integer);
22282 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
22286 -- Complete both implicit base and declared first subtype entities. The
22287 -- inheritance of the rep item chain ensures that SPARK-related pragmas
22288 -- are not clobbered when the signed integer type acts as a full view of
22291 Set_Etype (Implicit_Base, Base_Typ);
22292 Set_Size_Info (Implicit_Base, Base_Typ);
22293 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
22294 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
22295 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
22297 Set_Ekind (T, E_Signed_Integer_Subtype);
22298 Set_Etype (T, Implicit_Base);
22299 Set_Size_Info (T, Implicit_Base);
22300 Inherit_Rep_Item_Chain (T, Implicit_Base);
22301 Set_Scalar_Range (T, Def);
22302 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
22303 Set_Is_Constrained (T);
22304 end Signed_Integer_Type_Declaration;