1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, 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 Fname; use Fname;
42 with Freeze; use Freeze;
43 with Ghost; use Ghost;
44 with Itypes; use Itypes;
45 with Layout; use Layout;
47 with Lib.Xref; use Lib.Xref;
48 with Namet; use Namet;
49 with Nmake; use Nmake;
51 with Restrict; use Restrict;
52 with Rident; use Rident;
53 with Rtsfind; use Rtsfind;
55 with Sem_Aux; use Sem_Aux;
56 with Sem_Case; use Sem_Case;
57 with Sem_Cat; use Sem_Cat;
58 with Sem_Ch6; use Sem_Ch6;
59 with Sem_Ch7; use Sem_Ch7;
60 with Sem_Ch8; use Sem_Ch8;
61 with Sem_Ch13; use Sem_Ch13;
62 with Sem_Dim; use Sem_Dim;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Res; use Sem_Res;
69 with Sem_Smem; use Sem_Smem;
70 with Sem_Type; use Sem_Type;
71 with Sem_Util; use Sem_Util;
72 with Sem_Warn; use Sem_Warn;
73 with Stand; use Stand;
74 with Sinfo; use Sinfo;
75 with Sinput; use Sinput;
76 with Snames; use Snames;
77 with Targparm; use Targparm;
78 with Tbuild; use Tbuild;
79 with Ttypes; use Ttypes;
80 with Uintp; use Uintp;
81 with Urealp; use Urealp;
83 package body Sem_Ch3 is
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
90 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
91 -- abstract interface types implemented by a record type or a derived
94 procedure Build_Derived_Type
96 Parent_Type : Entity_Id;
97 Derived_Type : Entity_Id;
98 Is_Completion : Boolean;
99 Derive_Subps : Boolean := True);
100 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
101 -- the N_Full_Type_Declaration node containing the derived type definition.
102 -- Parent_Type is the entity for the parent type in the derived type
103 -- definition and Derived_Type the actual derived type. Is_Completion must
104 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
105 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
106 -- completion of a private type declaration. If Is_Completion is set to
107 -- True, N is the completion of a private type declaration and Derived_Type
108 -- is different from the defining identifier inside N (i.e. Derived_Type /=
109 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
110 -- subprograms should be derived. The only case where this parameter is
111 -- False is when Build_Derived_Type is recursively called to process an
112 -- implicit derived full type for a type derived from a private type (in
113 -- that case the subprograms must only be derived for the private view of
116 -- ??? These flags need a bit of re-examination and re-documentation:
117 -- ??? are they both necessary (both seem related to the recursion)?
119 procedure Build_Derived_Access_Type
121 Parent_Type : Entity_Id;
122 Derived_Type : Entity_Id);
123 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
124 -- create an implicit base if the parent type is constrained or if the
125 -- subtype indication has a constraint.
127 procedure Build_Derived_Array_Type
129 Parent_Type : Entity_Id;
130 Derived_Type : Entity_Id);
131 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
132 -- create an implicit base if the parent type is constrained or if the
133 -- subtype indication has a constraint.
135 procedure Build_Derived_Concurrent_Type
137 Parent_Type : Entity_Id;
138 Derived_Type : Entity_Id);
139 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
140 -- protected type, inherit entries and protected subprograms, check
141 -- legality of discriminant constraints if any.
143 procedure Build_Derived_Enumeration_Type
145 Parent_Type : Entity_Id;
146 Derived_Type : Entity_Id);
147 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
148 -- type, we must create a new list of literals. Types derived from
149 -- Character and [Wide_]Wide_Character are special-cased.
151 procedure Build_Derived_Numeric_Type
153 Parent_Type : Entity_Id;
154 Derived_Type : Entity_Id);
155 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
156 -- an anonymous base type, and propagate constraint to subtype if needed.
158 procedure Build_Derived_Private_Type
160 Parent_Type : Entity_Id;
161 Derived_Type : Entity_Id;
162 Is_Completion : Boolean;
163 Derive_Subps : Boolean := True);
164 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
165 -- because the parent may or may not have a completion, and the derivation
166 -- may itself be a completion.
168 procedure Build_Derived_Record_Type
170 Parent_Type : Entity_Id;
171 Derived_Type : Entity_Id;
172 Derive_Subps : Boolean := True);
173 -- Subsidiary procedure used for tagged and untagged record types
174 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
175 -- All parameters are as in Build_Derived_Type except that N, in
176 -- addition to being an N_Full_Type_Declaration node, can also be an
177 -- N_Private_Extension_Declaration node. See the definition of this routine
178 -- for much more info. Derive_Subps indicates whether subprograms should be
179 -- derived from the parent type. The only case where Derive_Subps is False
180 -- is for an implicit derived full type for a type derived from a private
181 -- type (see Build_Derived_Type).
183 procedure Build_Discriminal (Discrim : Entity_Id);
184 -- Create the discriminal corresponding to discriminant Discrim, that is
185 -- the parameter corresponding to Discrim to be used in initialization
186 -- procedures for the type where Discrim is a discriminant. Discriminals
187 -- are not used during semantic analysis, and are not fully defined
188 -- entities until expansion. Thus they are not given a scope until
189 -- initialization procedures are built.
191 function Build_Discriminant_Constraints
194 Derived_Def : Boolean := False) return Elist_Id;
195 -- Validate discriminant constraints and return the list of the constraints
196 -- in order of discriminant declarations, where T is the discriminated
197 -- unconstrained type. Def is the N_Subtype_Indication node where the
198 -- discriminants constraints for T are specified. Derived_Def is True
199 -- when building the discriminant constraints in a derived type definition
200 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
201 -- type and Def is the constraint "(xxx)" on T and this routine sets the
202 -- Corresponding_Discriminant field of the discriminants in the derived
203 -- type D to point to the corresponding discriminants in the parent type T.
205 procedure Build_Discriminated_Subtype
209 Related_Nod : Node_Id;
210 For_Access : Boolean := False);
211 -- Subsidiary procedure to Constrain_Discriminated_Type and to
212 -- Process_Incomplete_Dependents. Given
214 -- T (a possibly discriminated base type)
215 -- Def_Id (a very partially built subtype for T),
217 -- the call completes Def_Id to be the appropriate E_*_Subtype.
219 -- The Elist is the list of discriminant constraints if any (it is set
220 -- to No_Elist if T is not a discriminated type, and to an empty list if
221 -- T has discriminants but there are no discriminant constraints). The
222 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
223 -- The For_Access says whether or not this subtype is really constraining
224 -- an access type. That is its sole purpose is the designated type of an
225 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
226 -- is built to avoid freezing T when the access subtype is frozen.
228 function Build_Scalar_Bound
231 Der_T : Entity_Id) return Node_Id;
232 -- The bounds of a derived scalar type are conversions of the bounds of
233 -- the parent type. Optimize the representation if the bounds are literals.
234 -- Needs a more complete spec--what are the parameters exactly, and what
235 -- exactly is the returned value, and how is Bound affected???
237 procedure Build_Underlying_Full_View
241 -- If the completion of a private type is itself derived from a private
242 -- type, or if the full view of a private subtype is itself private, the
243 -- back-end has no way to compute the actual size of this type. We build
244 -- an internal subtype declaration of the proper parent type to convey
245 -- this information. This extra mechanism is needed because a full
246 -- view cannot itself have a full view (it would get clobbered during
249 procedure Check_Access_Discriminant_Requires_Limited
252 -- Check the restriction that the type to which an access discriminant
253 -- belongs must be a concurrent type or a descendant of a type with
254 -- the reserved word 'limited' in its declaration.
256 procedure Check_Anonymous_Access_Components
260 Comp_List : Node_Id);
261 -- Ada 2005 AI-382: an access component in a record definition can refer to
262 -- the enclosing record, in which case it denotes the type itself, and not
263 -- the current instance of the type. We create an anonymous access type for
264 -- the component, and flag it as an access to a component, so accessibility
265 -- checks are properly performed on it. The declaration of the access type
266 -- is placed ahead of that of the record to prevent order-of-elaboration
267 -- circularity issues in Gigi. We create an incomplete type for the record
268 -- declaration, which is the designated type of the anonymous access.
270 procedure Check_Delta_Expression (E : Node_Id);
271 -- Check that the expression represented by E is suitable for use as a
272 -- delta expression, i.e. it is of real type and is static.
274 procedure Check_Digits_Expression (E : Node_Id);
275 -- Check that the expression represented by E is suitable for use as a
276 -- digits expression, i.e. it is of integer type, positive and static.
278 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
279 -- Validate the initialization of an object declaration. T is the required
280 -- type, and Exp is the initialization expression.
282 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
283 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
285 procedure Check_Or_Process_Discriminants
288 Prev : Entity_Id := Empty);
289 -- If N is the full declaration of the completion T of an incomplete or
290 -- private type, check its discriminants (which are already known to be
291 -- conformant with those of the partial view, see Find_Type_Name),
292 -- otherwise process them. Prev is the entity of the partial declaration,
295 procedure Check_Real_Bound (Bound : Node_Id);
296 -- Check given bound for being of real type and static. If not, post an
297 -- appropriate message, and rewrite the bound with the real literal zero.
299 procedure Constant_Redeclaration
303 -- Various checks on legality of full declaration of deferred constant.
304 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
305 -- node. The caller has not yet set any attributes of this entity.
307 function Contain_Interface
309 Ifaces : Elist_Id) return Boolean;
310 -- Ada 2005: Determine whether Iface is present in the list Ifaces
312 procedure Convert_Scalar_Bounds
314 Parent_Type : Entity_Id;
315 Derived_Type : Entity_Id;
317 -- For derived scalar types, convert the bounds in the type definition to
318 -- the derived type, and complete their analysis. Given a constraint of the
319 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
320 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
321 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
322 -- subtype are conversions of those bounds to the derived_type, so that
323 -- their typing is consistent.
325 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
326 -- Copies attributes from array base type T2 to array base type T1. Copies
327 -- only attributes that apply to base types, but not subtypes.
329 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
330 -- Copies attributes from array subtype T2 to array subtype T1. Copies
331 -- attributes that apply to both subtypes and base types.
333 procedure Create_Constrained_Components
337 Constraints : Elist_Id);
338 -- Build the list of entities for a constrained discriminated record
339 -- subtype. If a component depends on a discriminant, replace its subtype
340 -- using the discriminant values in the discriminant constraint. Subt
341 -- is the defining identifier for the subtype whose list of constrained
342 -- entities we will create. Decl_Node is the type declaration node where
343 -- we will attach all the itypes created. Typ is the base discriminated
344 -- type for the subtype Subt. Constraints is the list of discriminant
345 -- constraints for Typ.
347 function Constrain_Component_Type
349 Constrained_Typ : Entity_Id;
350 Related_Node : Node_Id;
352 Constraints : Elist_Id) return Entity_Id;
353 -- Given a discriminated base type Typ, a list of discriminant constraints,
354 -- Constraints, for Typ and a component Comp of Typ, create and return the
355 -- type corresponding to Etype (Comp) where all discriminant references
356 -- are replaced with the corresponding constraint. If Etype (Comp) contains
357 -- no discriminant references then it is returned as-is. Constrained_Typ
358 -- is the final constrained subtype to which the constrained component
359 -- belongs. Related_Node is the node where we attach all created itypes.
361 procedure Constrain_Access
362 (Def_Id : in out Entity_Id;
364 Related_Nod : Node_Id);
365 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
366 -- an anonymous type created for a subtype indication. In that case it is
367 -- created in the procedure and attached to Related_Nod.
369 procedure Constrain_Array
370 (Def_Id : in out Entity_Id;
372 Related_Nod : Node_Id;
373 Related_Id : Entity_Id;
375 -- Apply a list of index constraints to an unconstrained array type. The
376 -- first parameter is the entity for the resulting subtype. A value of
377 -- Empty for Def_Id indicates that an implicit type must be created, but
378 -- creation is delayed (and must be done by this procedure) because other
379 -- subsidiary implicit types must be created first (which is why Def_Id
380 -- is an in/out parameter). The second parameter is a subtype indication
381 -- node for the constrained array to be created (e.g. something of the
382 -- form string (1 .. 10)). Related_Nod gives the place where this type
383 -- has to be inserted in the tree. The Related_Id and Suffix parameters
384 -- are used to build the associated Implicit type name.
386 procedure Constrain_Concurrent
387 (Def_Id : in out Entity_Id;
389 Related_Nod : Node_Id;
390 Related_Id : Entity_Id;
392 -- Apply list of discriminant constraints to an unconstrained concurrent
395 -- SI is the N_Subtype_Indication node containing the constraint and
396 -- the unconstrained type to constrain.
398 -- Def_Id is the entity for the resulting constrained subtype. A value
399 -- of Empty for Def_Id indicates that an implicit type must be created,
400 -- but creation is delayed (and must be done by this procedure) because
401 -- other subsidiary implicit types must be created first (which is why
402 -- Def_Id is an in/out parameter).
404 -- Related_Nod gives the place where this type has to be inserted
407 -- The last two arguments are used to create its external name if needed.
409 function Constrain_Corresponding_Record
410 (Prot_Subt : Entity_Id;
411 Corr_Rec : Entity_Id;
412 Related_Nod : Node_Id) return Entity_Id;
413 -- When constraining a protected type or task type with discriminants,
414 -- constrain the corresponding record with the same discriminant values.
416 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
417 -- Constrain a decimal fixed point type with a digits constraint and/or a
418 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
420 procedure Constrain_Discriminated_Type
423 Related_Nod : Node_Id;
424 For_Access : Boolean := False);
425 -- Process discriminant constraints of composite type. Verify that values
426 -- have been provided for all discriminants, that the original type is
427 -- unconstrained, and that the types of the supplied expressions match
428 -- the discriminant types. The first three parameters are like in routine
429 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
432 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
433 -- Constrain an enumeration type with a range constraint. This is identical
434 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
436 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
437 -- Constrain a floating point type with either a digits constraint
438 -- and/or a range constraint, building a E_Floating_Point_Subtype.
440 procedure Constrain_Index
443 Related_Nod : Node_Id;
444 Related_Id : Entity_Id;
447 -- Process an index constraint S in a constrained array declaration. The
448 -- constraint can be a subtype name, or a range with or without an explicit
449 -- subtype mark. The index is the corresponding index of the unconstrained
450 -- array. The Related_Id and Suffix parameters are used to build the
451 -- associated Implicit type name.
453 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
454 -- Build subtype of a signed or modular integer type
456 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
457 -- Constrain an ordinary fixed point type with a range constraint, and
458 -- build an E_Ordinary_Fixed_Point_Subtype entity.
460 procedure Copy_And_Swap (Priv, Full : Entity_Id);
461 -- Copy the Priv entity into the entity of its full declaration then swap
462 -- the two entities in such a manner that the former private type is now
463 -- seen as a full type.
465 procedure Decimal_Fixed_Point_Type_Declaration
468 -- Create a new decimal fixed point type, and apply the constraint to
469 -- obtain a subtype of this new type.
471 procedure Complete_Private_Subtype
474 Full_Base : Entity_Id;
475 Related_Nod : Node_Id);
476 -- Complete the implicit full view of a private subtype by setting the
477 -- appropriate semantic fields. If the full view of the parent is a record
478 -- type, build constrained components of subtype.
480 procedure Derive_Progenitor_Subprograms
481 (Parent_Type : Entity_Id;
482 Tagged_Type : Entity_Id);
483 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
484 -- operations of progenitors of Tagged_Type, and replace the subsidiary
485 -- subtypes with Tagged_Type, to build the specs of the inherited interface
486 -- primitives. The derived primitives are aliased to those of the
487 -- interface. This routine takes care also of transferring to the full view
488 -- subprograms associated with the partial view of Tagged_Type that cover
489 -- interface primitives.
491 procedure Derived_Standard_Character
493 Parent_Type : Entity_Id;
494 Derived_Type : Entity_Id);
495 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
496 -- derivations from types Standard.Character and Standard.Wide_Character.
498 procedure Derived_Type_Declaration
501 Is_Completion : Boolean);
502 -- Process a derived type declaration. Build_Derived_Type is invoked
503 -- to process the actual derived type definition. Parameters N and
504 -- Is_Completion have the same meaning as in Build_Derived_Type.
505 -- T is the N_Defining_Identifier for the entity defined in the
506 -- N_Full_Type_Declaration node N, that is T is the derived type.
508 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
509 -- Insert each literal in symbol table, as an overloadable identifier. Each
510 -- enumeration type is mapped into a sequence of integers, and each literal
511 -- is defined as a constant with integer value. If any of the literals are
512 -- character literals, the type is a character type, which means that
513 -- strings are legal aggregates for arrays of components of the type.
515 function Expand_To_Stored_Constraint
517 Constraint : Elist_Id) return Elist_Id;
518 -- Given a constraint (i.e. a list of expressions) on the discriminants of
519 -- Typ, expand it into a constraint on the stored discriminants and return
520 -- the new list of expressions constraining the stored discriminants.
522 function Find_Type_Of_Object
524 Related_Nod : Node_Id) return Entity_Id;
525 -- Get type entity for object referenced by Obj_Def, attaching the implicit
526 -- types generated to Related_Nod.
528 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
529 -- Create a new float and apply the constraint to obtain subtype of it
531 function Has_Range_Constraint (N : Node_Id) return Boolean;
532 -- Given an N_Subtype_Indication node N, return True if a range constraint
533 -- is present, either directly, or as part of a digits or delta constraint.
534 -- In addition, a digits constraint in the decimal case returns True, since
535 -- it establishes a default range if no explicit range is present.
537 function Inherit_Components
539 Parent_Base : Entity_Id;
540 Derived_Base : Entity_Id;
542 Inherit_Discr : Boolean;
543 Discs : Elist_Id) return Elist_Id;
544 -- Called from Build_Derived_Record_Type to inherit the components of
545 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
546 -- For more information on derived types and component inheritance please
547 -- consult the comment above the body of Build_Derived_Record_Type.
549 -- N is the original derived type declaration
551 -- Is_Tagged is set if we are dealing with tagged types
553 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
554 -- Parent_Base, otherwise no discriminants are inherited.
556 -- Discs gives the list of constraints that apply to Parent_Base in the
557 -- derived type declaration. If Discs is set to No_Elist, then we have
558 -- the following situation:
560 -- type Parent (D1..Dn : ..) is [tagged] record ...;
561 -- type Derived is new Parent [with ...];
563 -- which gets treated as
565 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
567 -- For untagged types the returned value is an association list. The list
568 -- starts from the association (Parent_Base => Derived_Base), and then it
569 -- contains a sequence of the associations of the form
571 -- (Old_Component => New_Component),
573 -- where Old_Component is the Entity_Id of a component in Parent_Base and
574 -- New_Component is the Entity_Id of the corresponding component in
575 -- Derived_Base. For untagged records, this association list is needed when
576 -- copying the record declaration for the derived base. In the tagged case
577 -- the value returned is irrelevant.
579 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
580 -- Propagate static and dynamic predicate flags from a parent to the
581 -- subtype in a subtype declaration with and without constraints.
583 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
584 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
585 -- Determine whether subprogram Subp is a procedure subject to pragma
586 -- Extensions_Visible with value False and has at least one controlling
587 -- parameter of mode OUT.
589 function Is_Valid_Constraint_Kind
591 Constraint_Kind : Node_Kind) return Boolean;
592 -- Returns True if it is legal to apply the given kind of constraint to the
593 -- given kind of type (index constraint to an array type, for example).
595 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
596 -- Create new modular type. Verify that modulus is in bounds
598 procedure New_Concatenation_Op (Typ : Entity_Id);
599 -- Create an abbreviated declaration for an operator in order to
600 -- materialize concatenation on array types.
602 procedure Ordinary_Fixed_Point_Type_Declaration
605 -- Create a new ordinary fixed point type, and apply the constraint to
606 -- obtain subtype of it.
608 procedure Prepare_Private_Subtype_Completion
610 Related_Nod : Node_Id);
611 -- Id is a subtype of some private type. Creates the full declaration
612 -- associated with Id whenever possible, i.e. when the full declaration
613 -- of the base type is already known. Records each subtype into
614 -- Private_Dependents of the base type.
616 procedure Process_Incomplete_Dependents
620 -- Process all entities that depend on an incomplete type. There include
621 -- subtypes, subprogram types that mention the incomplete type in their
622 -- profiles, and subprogram with access parameters that designate the
625 -- Inc_T is the defining identifier of an incomplete type declaration, its
626 -- Ekind is E_Incomplete_Type.
628 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
630 -- Full_T is N's defining identifier.
632 -- Subtypes of incomplete types with discriminants are completed when the
633 -- parent type is. This is simpler than private subtypes, because they can
634 -- only appear in the same scope, and there is no need to exchange views.
635 -- Similarly, access_to_subprogram types may have a parameter or a return
636 -- type that is an incomplete type, and that must be replaced with the
639 -- If the full type is tagged, subprogram with access parameters that
640 -- designated the incomplete may be primitive operations of the full type,
641 -- and have to be processed accordingly.
643 procedure Process_Real_Range_Specification (Def : Node_Id);
644 -- Given the type definition for a real type, this procedure processes and
645 -- checks the real range specification of this type definition if one is
646 -- present. If errors are found, error messages are posted, and the
647 -- Real_Range_Specification of Def is reset to Empty.
649 procedure Propagate_Default_Init_Cond_Attributes
650 (From_Typ : Entity_Id;
652 Parent_To_Derivation : Boolean := False;
653 Private_To_Full_View : Boolean := False);
654 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
655 -- all attributes related to pragma Default_Initial_Condition from From_Typ
656 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
657 -- the creation of a derived type. Flag Private_To_Full_View should be set
658 -- when processing both views of a private type.
660 procedure Record_Type_Declaration
664 -- Process a record type declaration (for both untagged and tagged
665 -- records). Parameters T and N are exactly like in procedure
666 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
667 -- for this routine. If this is the completion of an incomplete type
668 -- declaration, Prev is the entity of the incomplete declaration, used for
669 -- cross-referencing. Otherwise Prev = T.
671 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
672 -- This routine is used to process the actual record type definition (both
673 -- for untagged and tagged records). Def is a record type definition node.
674 -- This procedure analyzes the components in this record type definition.
675 -- Prev_T is the entity for the enclosing record type. It is provided so
676 -- that its Has_Task flag can be set if any of the component have Has_Task
677 -- set. If the declaration is the completion of an incomplete type
678 -- declaration, Prev_T is the original incomplete type, whose full view is
681 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
682 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
683 -- build a copy of the declaration tree of the parent, and we create
684 -- independently the list of components for the derived type. Semantic
685 -- information uses the component entities, but record representation
686 -- clauses are validated on the declaration tree. This procedure replaces
687 -- discriminants and components in the declaration with those that have
688 -- been created by Inherit_Components.
690 procedure Set_Fixed_Range
695 -- Build a range node with the given bounds and set it as the Scalar_Range
696 -- of the given fixed-point type entity. Loc is the source location used
697 -- for the constructed range. See body for further details.
699 procedure Set_Scalar_Range_For_Subtype
703 -- This routine is used to set the scalar range field for a subtype given
704 -- Def_Id, the entity for the subtype, and R, the range expression for the
705 -- scalar range. Subt provides the parent subtype to be used to analyze,
706 -- resolve, and check the given range.
708 procedure Set_Default_SSO (T : Entity_Id);
709 -- T is the entity for an array or record being declared. This procedure
710 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
711 -- to the setting of Opt.Default_SSO.
713 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
714 -- Create a new signed integer entity, and apply the constraint to obtain
715 -- the required first named subtype of this type.
717 procedure Set_Stored_Constraint_From_Discriminant_Constraint
719 -- E is some record type. This routine computes E's Stored_Constraint
720 -- from its Discriminant_Constraint.
722 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
723 -- Check that an entity in a list of progenitors is an interface,
724 -- emit error otherwise.
726 -----------------------
727 -- Access_Definition --
728 -----------------------
730 function Access_Definition
731 (Related_Nod : Node_Id;
732 N : Node_Id) return Entity_Id
734 Anon_Type : Entity_Id;
735 Anon_Scope : Entity_Id;
736 Desig_Type : Entity_Id;
737 Enclosing_Prot_Type : Entity_Id := Empty;
740 Check_SPARK_05_Restriction ("access type is not allowed", N);
742 if Is_Entry (Current_Scope)
743 and then Is_Task_Type (Etype (Scope (Current_Scope)))
745 Error_Msg_N ("task entries cannot have access parameters", N);
749 -- Ada 2005: For an object declaration the corresponding anonymous
750 -- type is declared in the current scope.
752 -- If the access definition is the return type of another access to
753 -- function, scope is the current one, because it is the one of the
754 -- current type declaration, except for the pathological case below.
756 if Nkind_In (Related_Nod, N_Object_Declaration,
757 N_Access_Function_Definition)
759 Anon_Scope := Current_Scope;
761 -- A pathological case: function returning access functions that
762 -- return access functions, etc. Each anonymous access type created
763 -- is in the enclosing scope of the outermost function.
770 while Nkind_In (Par, N_Access_Function_Definition,
776 if Nkind (Par) = N_Function_Specification then
777 Anon_Scope := Scope (Defining_Entity (Par));
781 -- For the anonymous function result case, retrieve the scope of the
782 -- function specification's associated entity rather than using the
783 -- current scope. The current scope will be the function itself if the
784 -- formal part is currently being analyzed, but will be the parent scope
785 -- in the case of a parameterless function, and we always want to use
786 -- the function's parent scope. Finally, if the function is a child
787 -- unit, we must traverse the tree to retrieve the proper entity.
789 elsif Nkind (Related_Nod) = N_Function_Specification
790 and then Nkind (Parent (N)) /= N_Parameter_Specification
792 -- If the current scope is a protected type, the anonymous access
793 -- is associated with one of the protected operations, and must
794 -- be available in the scope that encloses the protected declaration.
795 -- Otherwise the type is in the scope enclosing the subprogram.
797 -- If the function has formals, The return type of a subprogram
798 -- declaration is analyzed in the scope of the subprogram (see
799 -- Process_Formals) and thus the protected type, if present, is
800 -- the scope of the current function scope.
802 if Ekind (Current_Scope) = E_Protected_Type then
803 Enclosing_Prot_Type := Current_Scope;
805 elsif Ekind (Current_Scope) = E_Function
806 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
808 Enclosing_Prot_Type := Scope (Current_Scope);
811 if Present (Enclosing_Prot_Type) then
812 Anon_Scope := Scope (Enclosing_Prot_Type);
815 Anon_Scope := Scope (Defining_Entity (Related_Nod));
818 -- For an access type definition, if the current scope is a child
819 -- unit it is the scope of the type.
821 elsif Is_Compilation_Unit (Current_Scope) then
822 Anon_Scope := Current_Scope;
824 -- For access formals, access components, and access discriminants, the
825 -- scope is that of the enclosing declaration,
828 Anon_Scope := Scope (Current_Scope);
833 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
836 and then Ada_Version >= Ada_2005
838 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
841 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
842 -- the corresponding semantic routine
844 if Present (Access_To_Subprogram_Definition (N)) then
846 -- Compiler runtime units are compiled in Ada 2005 mode when building
847 -- the runtime library but must also be compilable in Ada 95 mode
848 -- (when bootstrapping the compiler).
850 Check_Compiler_Unit ("anonymous access to subprogram", N);
852 Access_Subprogram_Declaration
853 (T_Name => Anon_Type,
854 T_Def => Access_To_Subprogram_Definition (N));
856 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
858 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
860 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
863 Set_Can_Use_Internal_Rep
864 (Anon_Type, not Always_Compatible_Rep_On_Target);
866 -- If the anonymous access is associated with a protected operation,
867 -- create a reference to it after the enclosing protected definition
868 -- because the itype will be used in the subsequent bodies.
870 -- If the anonymous access itself is protected, a full type
871 -- declaratiton will be created for it, so that the equivalent
872 -- record type can be constructed. For further details, see
873 -- Replace_Anonymous_Access_To_Protected-Subprogram.
875 if Ekind (Current_Scope) = E_Protected_Type
876 and then not Protected_Present (Access_To_Subprogram_Definition (N))
878 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
884 Find_Type (Subtype_Mark (N));
885 Desig_Type := Entity (Subtype_Mark (N));
887 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
888 Set_Etype (Anon_Type, Anon_Type);
890 -- Make sure the anonymous access type has size and alignment fields
891 -- set, as required by gigi. This is necessary in the case of the
892 -- Task_Body_Procedure.
894 if not Has_Private_Component (Desig_Type) then
895 Layout_Type (Anon_Type);
898 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
899 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
900 -- the null value is allowed. In Ada 95 the null value is never allowed.
902 if Ada_Version >= Ada_2005 then
903 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
905 Set_Can_Never_Be_Null (Anon_Type, True);
908 -- The anonymous access type is as public as the discriminated type or
909 -- subprogram that defines it. It is imported (for back-end purposes)
910 -- if the designated type is.
912 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
914 -- Ada 2005 (AI-231): Propagate the access-constant attribute
916 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
918 -- The context is either a subprogram declaration, object declaration,
919 -- or an access discriminant, in a private or a full type declaration.
920 -- In the case of a subprogram, if the designated type is incomplete,
921 -- the operation will be a primitive operation of the full type, to be
922 -- updated subsequently. If the type is imported through a limited_with
923 -- clause, the subprogram is not a primitive operation of the type
924 -- (which is declared elsewhere in some other scope).
926 if Ekind (Desig_Type) = E_Incomplete_Type
927 and then not From_Limited_With (Desig_Type)
928 and then Is_Overloadable (Current_Scope)
930 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
931 Set_Has_Delayed_Freeze (Current_Scope);
934 -- Ada 2005: If the designated type is an interface that may contain
935 -- tasks, create a Master entity for the declaration. This must be done
936 -- before expansion of the full declaration, because the declaration may
937 -- include an expression that is an allocator, whose expansion needs the
938 -- proper Master for the created tasks.
940 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
942 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
944 Build_Class_Wide_Master (Anon_Type);
946 -- Similarly, if the type is an anonymous access that designates
947 -- tasks, create a master entity for it in the current context.
949 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
951 Build_Master_Entity (Defining_Identifier (Related_Nod));
952 Build_Master_Renaming (Anon_Type);
956 -- For a private component of a protected type, it is imperative that
957 -- the back-end elaborate the type immediately after the protected
958 -- declaration, because this type will be used in the declarations
959 -- created for the component within each protected body, so we must
960 -- create an itype reference for it now.
962 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
963 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
965 -- Similarly, if the access definition is the return result of a
966 -- function, create an itype reference for it because it will be used
967 -- within the function body. For a regular function that is not a
968 -- compilation unit, insert reference after the declaration. For a
969 -- protected operation, insert it after the enclosing protected type
970 -- declaration. In either case, do not create a reference for a type
971 -- obtained through a limited_with clause, because this would introduce
972 -- semantic dependencies.
974 -- Similarly, do not create a reference if the designated type is a
975 -- generic formal, because no use of it will reach the backend.
977 elsif Nkind (Related_Nod) = N_Function_Specification
978 and then not From_Limited_With (Desig_Type)
979 and then not Is_Generic_Type (Desig_Type)
981 if Present (Enclosing_Prot_Type) then
982 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
984 elsif Is_List_Member (Parent (Related_Nod))
985 and then Nkind (Parent (N)) /= N_Parameter_Specification
987 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
990 -- Finally, create an itype reference for an object declaration of an
991 -- anonymous access type. This is strictly necessary only for deferred
992 -- constants, but in any case will avoid out-of-scope problems in the
995 elsif Nkind (Related_Nod) = N_Object_Declaration then
996 Build_Itype_Reference (Anon_Type, Related_Nod);
1000 end Access_Definition;
1002 -----------------------------------
1003 -- Access_Subprogram_Declaration --
1004 -----------------------------------
1006 procedure Access_Subprogram_Declaration
1007 (T_Name : Entity_Id;
1010 procedure Check_For_Premature_Usage (Def : Node_Id);
1011 -- Check that type T_Name is not used, directly or recursively, as a
1012 -- parameter or a return type in Def. Def is either a subtype, an
1013 -- access_definition, or an access_to_subprogram_definition.
1015 -------------------------------
1016 -- Check_For_Premature_Usage --
1017 -------------------------------
1019 procedure Check_For_Premature_Usage (Def : Node_Id) is
1023 -- Check for a subtype mark
1025 if Nkind (Def) in N_Has_Etype then
1026 if Etype (Def) = T_Name then
1028 ("type& cannot be used before end of its declaration", Def);
1031 -- If this is not a subtype, then this is an access_definition
1033 elsif Nkind (Def) = N_Access_Definition then
1034 if Present (Access_To_Subprogram_Definition (Def)) then
1035 Check_For_Premature_Usage
1036 (Access_To_Subprogram_Definition (Def));
1038 Check_For_Premature_Usage (Subtype_Mark (Def));
1041 -- The only cases left are N_Access_Function_Definition and
1042 -- N_Access_Procedure_Definition.
1045 if Present (Parameter_Specifications (Def)) then
1046 Param := First (Parameter_Specifications (Def));
1047 while Present (Param) loop
1048 Check_For_Premature_Usage (Parameter_Type (Param));
1049 Param := Next (Param);
1053 if Nkind (Def) = N_Access_Function_Definition then
1054 Check_For_Premature_Usage (Result_Definition (Def));
1057 end Check_For_Premature_Usage;
1061 Formals : constant List_Id := Parameter_Specifications (T_Def);
1064 Desig_Type : constant Entity_Id :=
1065 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1067 -- Start of processing for Access_Subprogram_Declaration
1070 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1072 -- Associate the Itype node with the inner full-type declaration or
1073 -- subprogram spec or entry body. This is required to handle nested
1074 -- anonymous declarations. For example:
1077 -- (X : access procedure
1078 -- (Y : access procedure
1081 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1082 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1083 N_Private_Type_Declaration,
1084 N_Private_Extension_Declaration,
1085 N_Procedure_Specification,
1086 N_Function_Specification,
1090 Nkind_In (D_Ityp, N_Object_Declaration,
1091 N_Object_Renaming_Declaration,
1092 N_Formal_Object_Declaration,
1093 N_Formal_Type_Declaration,
1094 N_Task_Type_Declaration,
1095 N_Protected_Type_Declaration))
1097 D_Ityp := Parent (D_Ityp);
1098 pragma Assert (D_Ityp /= Empty);
1101 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1103 if Nkind_In (D_Ityp, N_Procedure_Specification,
1104 N_Function_Specification)
1106 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1108 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1109 N_Object_Declaration,
1110 N_Object_Renaming_Declaration,
1111 N_Formal_Type_Declaration)
1113 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1116 if Nkind (T_Def) = N_Access_Function_Definition then
1117 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1119 Acc : constant Node_Id := Result_Definition (T_Def);
1122 if Present (Access_To_Subprogram_Definition (Acc))
1124 Protected_Present (Access_To_Subprogram_Definition (Acc))
1128 Replace_Anonymous_Access_To_Protected_Subprogram
1134 Access_Definition (T_Def, Result_Definition (T_Def)));
1139 Analyze (Result_Definition (T_Def));
1142 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1145 -- If a null exclusion is imposed on the result type, then
1146 -- create a null-excluding itype (an access subtype) and use
1147 -- it as the function's Etype.
1149 if Is_Access_Type (Typ)
1150 and then Null_Exclusion_In_Return_Present (T_Def)
1152 Set_Etype (Desig_Type,
1153 Create_Null_Excluding_Itype
1155 Related_Nod => T_Def,
1156 Scope_Id => Current_Scope));
1159 if From_Limited_With (Typ) then
1161 -- AI05-151: Incomplete types are allowed in all basic
1162 -- declarations, including access to subprograms.
1164 if Ada_Version >= Ada_2012 then
1169 ("illegal use of incomplete type&",
1170 Result_Definition (T_Def), Typ);
1173 elsif Ekind (Current_Scope) = E_Package
1174 and then In_Private_Part (Current_Scope)
1176 if Ekind (Typ) = E_Incomplete_Type then
1177 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1179 elsif Is_Class_Wide_Type (Typ)
1180 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1183 (Desig_Type, Private_Dependents (Etype (Typ)));
1187 Set_Etype (Desig_Type, Typ);
1192 if not (Is_Type (Etype (Desig_Type))) then
1194 ("expect type in function specification",
1195 Result_Definition (T_Def));
1199 Set_Etype (Desig_Type, Standard_Void_Type);
1202 if Present (Formals) then
1203 Push_Scope (Desig_Type);
1205 -- Some special tests here. These special tests can be removed
1206 -- if and when Itypes always have proper parent pointers to their
1209 -- Special test 1) Link defining_identifier of formals. Required by
1210 -- First_Formal to provide its functionality.
1216 F := First (Formals);
1218 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1219 -- when it is part of an unconstrained type and subtype expansion
1220 -- is disabled. To avoid back-end problems with shared profiles,
1221 -- use previous subprogram type as the designated type, and then
1222 -- remove scope added above.
1224 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1226 Set_Etype (T_Name, T_Name);
1227 Init_Size_Align (T_Name);
1228 Set_Directly_Designated_Type (T_Name,
1229 Scope (Defining_Identifier (F)));
1234 while Present (F) loop
1235 if No (Parent (Defining_Identifier (F))) then
1236 Set_Parent (Defining_Identifier (F), F);
1243 Process_Formals (Formals, Parent (T_Def));
1245 -- Special test 2) End_Scope requires that the parent pointer be set
1246 -- to something reasonable, but Itypes don't have parent pointers. So
1247 -- we set it and then unset it ???
1249 Set_Parent (Desig_Type, T_Name);
1251 Set_Parent (Desig_Type, Empty);
1254 -- Check for premature usage of the type being defined
1256 Check_For_Premature_Usage (T_Def);
1258 -- The return type and/or any parameter type may be incomplete. Mark the
1259 -- subprogram_type as depending on the incomplete type, so that it can
1260 -- be updated when the full type declaration is seen. This only applies
1261 -- to incomplete types declared in some enclosing scope, not to limited
1262 -- views from other packages.
1264 -- Prior to Ada 2012, access to functions can only have in_parameters.
1266 if Present (Formals) then
1267 Formal := First_Formal (Desig_Type);
1268 while Present (Formal) loop
1269 if Ekind (Formal) /= E_In_Parameter
1270 and then Nkind (T_Def) = N_Access_Function_Definition
1271 and then Ada_Version < Ada_2012
1273 Error_Msg_N ("functions can only have IN parameters", Formal);
1276 if Ekind (Etype (Formal)) = E_Incomplete_Type
1277 and then In_Open_Scopes (Scope (Etype (Formal)))
1279 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1280 Set_Has_Delayed_Freeze (Desig_Type);
1283 Next_Formal (Formal);
1287 -- Check whether an indirect call without actuals may be possible. This
1288 -- is used when resolving calls whose result is then indexed.
1290 May_Need_Actuals (Desig_Type);
1292 -- If the return type is incomplete, this is legal as long as the type
1293 -- is declared in the current scope and will be completed in it (rather
1294 -- than being part of limited view).
1296 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1297 and then not Has_Delayed_Freeze (Desig_Type)
1298 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1300 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1301 Set_Has_Delayed_Freeze (Desig_Type);
1304 Check_Delayed_Subprogram (Desig_Type);
1306 if Protected_Present (T_Def) then
1307 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1308 Set_Convention (Desig_Type, Convention_Protected);
1310 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1313 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1315 Set_Etype (T_Name, T_Name);
1316 Init_Size_Align (T_Name);
1317 Set_Directly_Designated_Type (T_Name, Desig_Type);
1319 Generate_Reference_To_Formals (T_Name);
1321 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1323 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1325 Check_Restriction (No_Access_Subprograms, T_Def);
1326 end Access_Subprogram_Declaration;
1328 ----------------------------
1329 -- Access_Type_Declaration --
1330 ----------------------------
1332 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1333 P : constant Node_Id := Parent (Def);
1334 S : constant Node_Id := Subtype_Indication (Def);
1336 Full_Desig : Entity_Id;
1339 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1341 -- Check for permissible use of incomplete type
1343 if Nkind (S) /= N_Subtype_Indication then
1346 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1347 Set_Directly_Designated_Type (T, Entity (S));
1349 -- If the designated type is a limited view, we cannot tell if
1350 -- the full view contains tasks, and there is no way to handle
1351 -- that full view in a client. We create a master entity for the
1352 -- scope, which will be used when a client determines that one
1355 if From_Limited_With (Entity (S))
1356 and then not Is_Class_Wide_Type (Entity (S))
1358 Set_Ekind (T, E_Access_Type);
1359 Build_Master_Entity (T);
1360 Build_Master_Renaming (T);
1364 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1367 -- If the access definition is of the form: ACCESS NOT NULL ..
1368 -- the subtype indication must be of an access type. Create
1369 -- a null-excluding subtype of it.
1371 if Null_Excluding_Subtype (Def) then
1372 if not Is_Access_Type (Entity (S)) then
1373 Error_Msg_N ("null exclusion must apply to access type", Def);
1377 Loc : constant Source_Ptr := Sloc (S);
1379 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1383 Make_Subtype_Declaration (Loc,
1384 Defining_Identifier => Nam,
1385 Subtype_Indication =>
1386 New_Occurrence_Of (Entity (S), Loc));
1387 Set_Null_Exclusion_Present (Decl);
1388 Insert_Before (Parent (Def), Decl);
1390 Set_Entity (S, Nam);
1396 Set_Directly_Designated_Type (T,
1397 Process_Subtype (S, P, T, 'P'));
1400 if All_Present (Def) or Constant_Present (Def) then
1401 Set_Ekind (T, E_General_Access_Type);
1403 Set_Ekind (T, E_Access_Type);
1406 Full_Desig := Designated_Type (T);
1408 if Base_Type (Full_Desig) = T then
1409 Error_Msg_N ("access type cannot designate itself", S);
1411 -- In Ada 2005, the type may have a limited view through some unit in
1412 -- its own context, allowing the following circularity that cannot be
1413 -- detected earlier.
1415 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1418 ("access type cannot designate its own classwide type", S);
1420 -- Clean up indication of tagged status to prevent cascaded errors
1422 Set_Is_Tagged_Type (T, False);
1427 -- If the type has appeared already in a with_type clause, it is frozen
1428 -- and the pointer size is already set. Else, initialize.
1430 if not From_Limited_With (T) then
1431 Init_Size_Align (T);
1434 -- Note that Has_Task is always false, since the access type itself
1435 -- is not a task type. See Einfo for more description on this point.
1436 -- Exactly the same consideration applies to Has_Controlled_Component
1437 -- and to Has_Protected.
1439 Set_Has_Task (T, False);
1440 Set_Has_Protected (T, False);
1441 Set_Has_Timing_Event (T, False);
1442 Set_Has_Controlled_Component (T, False);
1444 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1445 -- problems where an incomplete view of this entity has been previously
1446 -- established by a limited with and an overlaid version of this field
1447 -- (Stored_Constraint) was initialized for the incomplete view.
1449 -- This reset is performed in most cases except where the access type
1450 -- has been created for the purposes of allocating or deallocating a
1451 -- build-in-place object. Such access types have explicitly set pools
1452 -- and finalization masters.
1454 if No (Associated_Storage_Pool (T)) then
1455 Set_Finalization_Master (T, Empty);
1458 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1461 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1462 Set_Is_Access_Constant (T, Constant_Present (Def));
1463 end Access_Type_Declaration;
1465 ----------------------------------
1466 -- Add_Interface_Tag_Components --
1467 ----------------------------------
1469 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1470 Loc : constant Source_Ptr := Sloc (N);
1474 procedure Add_Tag (Iface : Entity_Id);
1475 -- Add tag for one of the progenitor interfaces
1481 procedure Add_Tag (Iface : Entity_Id) is
1488 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1490 -- This is a reasonable place to propagate predicates
1492 if Has_Predicates (Iface) then
1493 Set_Has_Predicates (Typ);
1497 Make_Component_Definition (Loc,
1498 Aliased_Present => True,
1499 Subtype_Indication =>
1500 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1502 Tag := Make_Temporary (Loc, 'V');
1505 Make_Component_Declaration (Loc,
1506 Defining_Identifier => Tag,
1507 Component_Definition => Def);
1509 Analyze_Component_Declaration (Decl);
1511 Set_Analyzed (Decl);
1512 Set_Ekind (Tag, E_Component);
1514 Set_Is_Aliased (Tag);
1515 Set_Related_Type (Tag, Iface);
1516 Init_Component_Location (Tag);
1518 pragma Assert (Is_Frozen (Iface));
1520 Set_DT_Entry_Count (Tag,
1521 DT_Entry_Count (First_Entity (Iface)));
1523 if No (Last_Tag) then
1526 Insert_After (Last_Tag, Decl);
1531 -- If the ancestor has discriminants we need to give special support
1532 -- to store the offset_to_top value of the secondary dispatch tables.
1533 -- For this purpose we add a supplementary component just after the
1534 -- field that contains the tag associated with each secondary DT.
1536 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1538 Make_Component_Definition (Loc,
1539 Subtype_Indication =>
1540 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1542 Offset := Make_Temporary (Loc, 'V');
1545 Make_Component_Declaration (Loc,
1546 Defining_Identifier => Offset,
1547 Component_Definition => Def);
1549 Analyze_Component_Declaration (Decl);
1551 Set_Analyzed (Decl);
1552 Set_Ekind (Offset, E_Component);
1553 Set_Is_Aliased (Offset);
1554 Set_Related_Type (Offset, Iface);
1555 Init_Component_Location (Offset);
1556 Insert_After (Last_Tag, Decl);
1567 -- Start of processing for Add_Interface_Tag_Components
1570 if not RTE_Available (RE_Interface_Tag) then
1572 ("(Ada 2005) interface types not supported by this run-time!",
1577 if Ekind (Typ) /= E_Record_Type
1578 or else (Is_Concurrent_Record_Type (Typ)
1579 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1580 or else (not Is_Concurrent_Record_Type (Typ)
1581 and then No (Interfaces (Typ))
1582 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1587 -- Find the current last tag
1589 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1590 Ext := Record_Extension_Part (Type_Definition (N));
1592 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1593 Ext := Type_Definition (N);
1598 if not (Present (Component_List (Ext))) then
1599 Set_Null_Present (Ext, False);
1601 Set_Component_List (Ext,
1602 Make_Component_List (Loc,
1603 Component_Items => L,
1604 Null_Present => False));
1606 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1607 L := Component_Items
1609 (Record_Extension_Part
1610 (Type_Definition (N))));
1612 L := Component_Items
1614 (Type_Definition (N)));
1617 -- Find the last tag component
1620 while Present (Comp) loop
1621 if Nkind (Comp) = N_Component_Declaration
1622 and then Is_Tag (Defining_Identifier (Comp))
1631 -- At this point L references the list of components and Last_Tag
1632 -- references the current last tag (if any). Now we add the tag
1633 -- corresponding with all the interfaces that are not implemented
1636 if Present (Interfaces (Typ)) then
1637 Elmt := First_Elmt (Interfaces (Typ));
1638 while Present (Elmt) loop
1639 Add_Tag (Node (Elmt));
1643 end Add_Interface_Tag_Components;
1645 -------------------------------------
1646 -- Add_Internal_Interface_Entities --
1647 -------------------------------------
1649 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1652 Iface_Elmt : Elmt_Id;
1653 Iface_Prim : Entity_Id;
1654 Ifaces_List : Elist_Id;
1655 New_Subp : Entity_Id := Empty;
1657 Restore_Scope : Boolean := False;
1660 pragma Assert (Ada_Version >= Ada_2005
1661 and then Is_Record_Type (Tagged_Type)
1662 and then Is_Tagged_Type (Tagged_Type)
1663 and then Has_Interfaces (Tagged_Type)
1664 and then not Is_Interface (Tagged_Type));
1666 -- Ensure that the internal entities are added to the scope of the type
1668 if Scope (Tagged_Type) /= Current_Scope then
1669 Push_Scope (Scope (Tagged_Type));
1670 Restore_Scope := True;
1673 Collect_Interfaces (Tagged_Type, Ifaces_List);
1675 Iface_Elmt := First_Elmt (Ifaces_List);
1676 while Present (Iface_Elmt) loop
1677 Iface := Node (Iface_Elmt);
1679 -- Originally we excluded here from this processing interfaces that
1680 -- are parents of Tagged_Type because their primitives are located
1681 -- in the primary dispatch table (and hence no auxiliary internal
1682 -- entities are required to handle secondary dispatch tables in such
1683 -- case). However, these auxiliary entities are also required to
1684 -- handle derivations of interfaces in formals of generics (see
1685 -- Derive_Subprograms).
1687 Elmt := First_Elmt (Primitive_Operations (Iface));
1688 while Present (Elmt) loop
1689 Iface_Prim := Node (Elmt);
1691 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1693 Find_Primitive_Covering_Interface
1694 (Tagged_Type => Tagged_Type,
1695 Iface_Prim => Iface_Prim);
1697 if No (Prim) and then Serious_Errors_Detected > 0 then
1701 pragma Assert (Present (Prim));
1703 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1704 -- differs from the name of the interface primitive then it is
1705 -- a private primitive inherited from a parent type. In such
1706 -- case, given that Tagged_Type covers the interface, the
1707 -- inherited private primitive becomes visible. For such
1708 -- purpose we add a new entity that renames the inherited
1709 -- private primitive.
1711 if Chars (Prim) /= Chars (Iface_Prim) then
1712 pragma Assert (Has_Suffix (Prim, 'P'));
1714 (New_Subp => New_Subp,
1715 Parent_Subp => Iface_Prim,
1716 Derived_Type => Tagged_Type,
1717 Parent_Type => Iface);
1718 Set_Alias (New_Subp, Prim);
1719 Set_Is_Abstract_Subprogram
1720 (New_Subp, Is_Abstract_Subprogram (Prim));
1724 (New_Subp => New_Subp,
1725 Parent_Subp => Iface_Prim,
1726 Derived_Type => Tagged_Type,
1727 Parent_Type => Iface);
1729 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1730 -- associated with interface types. These entities are
1731 -- only registered in the list of primitives of its
1732 -- corresponding tagged type because they are only used
1733 -- to fill the contents of the secondary dispatch tables.
1734 -- Therefore they are removed from the homonym chains.
1736 Set_Is_Hidden (New_Subp);
1737 Set_Is_Internal (New_Subp);
1738 Set_Alias (New_Subp, Prim);
1739 Set_Is_Abstract_Subprogram
1740 (New_Subp, Is_Abstract_Subprogram (Prim));
1741 Set_Interface_Alias (New_Subp, Iface_Prim);
1743 -- If the returned type is an interface then propagate it to
1744 -- the returned type. Needed by the thunk to generate the code
1745 -- which displaces "this" to reference the corresponding
1746 -- secondary dispatch table in the returned object.
1748 if Is_Interface (Etype (Iface_Prim)) then
1749 Set_Etype (New_Subp, Etype (Iface_Prim));
1752 -- Internal entities associated with interface types are only
1753 -- registered in the list of primitives of the tagged type.
1754 -- They are only used to fill the contents of the secondary
1755 -- dispatch tables. Therefore they are not needed in the
1758 Remove_Homonym (New_Subp);
1760 -- Hidden entities associated with interfaces must have set
1761 -- the Has_Delay_Freeze attribute to ensure that, in case
1762 -- of locally defined tagged types (or compiling with static
1763 -- dispatch tables generation disabled) the corresponding
1764 -- entry of the secondary dispatch table is filled when such
1765 -- an entity is frozen. This is an expansion activity that must
1766 -- be suppressed for ASIS because it leads to gigi elaboration
1767 -- issues in annotate mode.
1769 if not ASIS_Mode then
1770 Set_Has_Delayed_Freeze (New_Subp);
1778 Next_Elmt (Iface_Elmt);
1781 if Restore_Scope then
1784 end Add_Internal_Interface_Entities;
1786 -----------------------------------
1787 -- Analyze_Component_Declaration --
1788 -----------------------------------
1790 procedure Analyze_Component_Declaration (N : Node_Id) is
1791 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1792 Id : constant Entity_Id := Defining_Identifier (N);
1793 E : constant Node_Id := Expression (N);
1794 Typ : constant Node_Id :=
1795 Subtype_Indication (Component_Definition (N));
1799 function Contains_POC (Constr : Node_Id) return Boolean;
1800 -- Determines whether a constraint uses the discriminant of a record
1801 -- type thus becoming a per-object constraint (POC).
1803 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1804 -- Typ is the type of the current component, check whether this type is
1805 -- a limited type. Used to validate declaration against that of
1806 -- enclosing record.
1812 function Contains_POC (Constr : Node_Id) return Boolean is
1814 -- Prevent cascaded errors
1816 if Error_Posted (Constr) then
1820 case Nkind (Constr) is
1821 when N_Attribute_Reference =>
1822 return Attribute_Name (Constr) = Name_Access
1823 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1825 when N_Discriminant_Association =>
1826 return Denotes_Discriminant (Expression (Constr));
1828 when N_Identifier =>
1829 return Denotes_Discriminant (Constr);
1831 when N_Index_Or_Discriminant_Constraint =>
1836 IDC := First (Constraints (Constr));
1837 while Present (IDC) loop
1839 -- One per-object constraint is sufficient
1841 if Contains_POC (IDC) then
1852 return Denotes_Discriminant (Low_Bound (Constr))
1854 Denotes_Discriminant (High_Bound (Constr));
1856 when N_Range_Constraint =>
1857 return Denotes_Discriminant (Range_Expression (Constr));
1865 ----------------------
1866 -- Is_Known_Limited --
1867 ----------------------
1869 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1870 P : constant Entity_Id := Etype (Typ);
1871 R : constant Entity_Id := Root_Type (Typ);
1874 if Is_Limited_Record (Typ) then
1877 -- If the root type is limited (and not a limited interface)
1878 -- so is the current type
1880 elsif Is_Limited_Record (R)
1881 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1885 -- Else the type may have a limited interface progenitor, but a
1886 -- limited record parent.
1888 elsif R /= P and then Is_Limited_Record (P) then
1894 end Is_Known_Limited;
1896 -- Start of processing for Analyze_Component_Declaration
1899 Generate_Definition (Id);
1902 if Present (Typ) then
1903 T := Find_Type_Of_Object
1904 (Subtype_Indication (Component_Definition (N)), N);
1906 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1907 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1910 -- Ada 2005 (AI-230): Access Definition case
1913 pragma Assert (Present
1914 (Access_Definition (Component_Definition (N))));
1916 T := Access_Definition
1918 N => Access_Definition (Component_Definition (N)));
1919 Set_Is_Local_Anonymous_Access (T);
1921 -- Ada 2005 (AI-254)
1923 if Present (Access_To_Subprogram_Definition
1924 (Access_Definition (Component_Definition (N))))
1925 and then Protected_Present (Access_To_Subprogram_Definition
1927 (Component_Definition (N))))
1929 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1933 -- If the subtype is a constrained subtype of the enclosing record,
1934 -- (which must have a partial view) the back-end does not properly
1935 -- handle the recursion. Rewrite the component declaration with an
1936 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1937 -- the tree directly because side effects have already been removed from
1938 -- discriminant constraints.
1940 if Ekind (T) = E_Access_Subtype
1941 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1942 and then Comes_From_Source (T)
1943 and then Nkind (Parent (T)) = N_Subtype_Declaration
1944 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1947 (Subtype_Indication (Component_Definition (N)),
1948 New_Copy_Tree (Subtype_Indication (Parent (T))));
1949 T := Find_Type_Of_Object
1950 (Subtype_Indication (Component_Definition (N)), N);
1953 -- If the component declaration includes a default expression, then we
1954 -- check that the component is not of a limited type (RM 3.7(5)),
1955 -- and do the special preanalysis of the expression (see section on
1956 -- "Handling of Default and Per-Object Expressions" in the spec of
1960 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1961 Preanalyze_Default_Expression (E, T);
1962 Check_Initialization (T, E);
1964 if Ada_Version >= Ada_2005
1965 and then Ekind (T) = E_Anonymous_Access_Type
1966 and then Etype (E) /= Any_Type
1968 -- Check RM 3.9.2(9): "if the expected type for an expression is
1969 -- an anonymous access-to-specific tagged type, then the object
1970 -- designated by the expression shall not be dynamically tagged
1971 -- unless it is a controlling operand in a call on a dispatching
1974 if Is_Tagged_Type (Directly_Designated_Type (T))
1976 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1978 Ekind (Directly_Designated_Type (Etype (E))) =
1982 ("access to specific tagged type required (RM 3.9.2(9))", E);
1985 -- (Ada 2005: AI-230): Accessibility check for anonymous
1988 if Type_Access_Level (Etype (E)) >
1989 Deepest_Type_Access_Level (T)
1992 ("expression has deeper access level than component " &
1993 "(RM 3.10.2 (12.2))", E);
1996 -- The initialization expression is a reference to an access
1997 -- discriminant. The type of the discriminant is always deeper
1998 -- than any access type.
2000 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2001 and then Is_Entity_Name (E)
2002 and then Ekind (Entity (E)) = E_In_Parameter
2003 and then Present (Discriminal_Link (Entity (E)))
2006 ("discriminant has deeper accessibility level than target",
2012 -- The parent type may be a private view with unknown discriminants,
2013 -- and thus unconstrained. Regular components must be constrained.
2015 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2016 if Is_Class_Wide_Type (T) then
2018 ("class-wide subtype with unknown discriminants" &
2019 " in component declaration",
2020 Subtype_Indication (Component_Definition (N)));
2023 ("unconstrained subtype in component declaration",
2024 Subtype_Indication (Component_Definition (N)));
2027 -- Components cannot be abstract, except for the special case of
2028 -- the _Parent field (case of extending an abstract tagged type)
2030 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2031 Error_Msg_N ("type of a component cannot be abstract", N);
2035 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2037 -- The component declaration may have a per-object constraint, set
2038 -- the appropriate flag in the defining identifier of the subtype.
2040 if Present (Subtype_Indication (Component_Definition (N))) then
2042 Sindic : constant Node_Id :=
2043 Subtype_Indication (Component_Definition (N));
2045 if Nkind (Sindic) = N_Subtype_Indication
2046 and then Present (Constraint (Sindic))
2047 and then Contains_POC (Constraint (Sindic))
2049 Set_Has_Per_Object_Constraint (Id);
2054 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2055 -- out some static checks.
2057 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2058 Null_Exclusion_Static_Checks (N);
2061 -- If this component is private (or depends on a private type), flag the
2062 -- record type to indicate that some operations are not available.
2064 P := Private_Component (T);
2068 -- Check for circular definitions
2070 if P = Any_Type then
2071 Set_Etype (Id, Any_Type);
2073 -- There is a gap in the visibility of operations only if the
2074 -- component type is not defined in the scope of the record type.
2076 elsif Scope (P) = Scope (Current_Scope) then
2079 elsif Is_Limited_Type (P) then
2080 Set_Is_Limited_Composite (Current_Scope);
2083 Set_Is_Private_Composite (Current_Scope);
2088 and then Is_Limited_Type (T)
2089 and then Chars (Id) /= Name_uParent
2090 and then Is_Tagged_Type (Current_Scope)
2092 if Is_Derived_Type (Current_Scope)
2093 and then not Is_Known_Limited (Current_Scope)
2096 ("extension of nonlimited type cannot have limited components",
2099 if Is_Interface (Root_Type (Current_Scope)) then
2101 ("\limitedness is not inherited from limited interface", N);
2102 Error_Msg_N ("\add LIMITED to type indication", N);
2105 Explain_Limited_Type (T, N);
2106 Set_Etype (Id, Any_Type);
2107 Set_Is_Limited_Composite (Current_Scope, False);
2109 elsif not Is_Derived_Type (Current_Scope)
2110 and then not Is_Limited_Record (Current_Scope)
2111 and then not Is_Concurrent_Type (Current_Scope)
2114 ("nonlimited tagged type cannot have limited components", N);
2115 Explain_Limited_Type (T, N);
2116 Set_Etype (Id, Any_Type);
2117 Set_Is_Limited_Composite (Current_Scope, False);
2121 -- If the component is an unconstrained task or protected type with
2122 -- discriminants, the component and the enclosing record are limited
2123 -- and the component is constrained by its default values. Compute
2124 -- its actual subtype, else it may be allocated the maximum size by
2125 -- the backend, and possibly overflow.
2127 if Is_Concurrent_Type (T)
2128 and then not Is_Constrained (T)
2129 and then Has_Discriminants (T)
2130 and then not Has_Discriminants (Current_Scope)
2133 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2136 Set_Etype (Id, Act_T);
2138 -- Rewrite component definition to use the constrained subtype
2140 Rewrite (Component_Definition (N),
2141 Make_Component_Definition (Loc,
2142 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2146 Set_Original_Record_Component (Id, Id);
2148 if Has_Aspects (N) then
2149 Analyze_Aspect_Specifications (N, Id);
2152 Analyze_Dimension (N);
2153 end Analyze_Component_Declaration;
2155 --------------------------
2156 -- Analyze_Declarations --
2157 --------------------------
2159 procedure Analyze_Declarations (L : List_Id) is
2162 procedure Adjust_Decl;
2163 -- Adjust Decl not to include implicit label declarations, since these
2164 -- have strange Sloc values that result in elaboration check problems.
2165 -- (They have the sloc of the label as found in the source, and that
2166 -- is ahead of the current declarative part).
2168 procedure Check_Entry_Contracts;
2169 -- Perform a pre-analysis of the pre- and postconditions of an entry
2170 -- declaration. This must be done before full resolution and creation
2171 -- of the parameter block, etc. to catch illegal uses within the
2172 -- contract expression. Full analysis of the expression is done when
2173 -- the contract is processed.
2175 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2176 -- Determine whether Body_Decl denotes the body of a late controlled
2177 -- primitive (either Initialize, Adjust or Finalize). If this is the
2178 -- case, add a proper spec if the body lacks one. The spec is inserted
2179 -- before Body_Decl and immediately analyzed.
2181 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2182 -- Spec_Id is the entity of a package that may define abstract states.
2183 -- If the states have visible refinement, remove the visibility of each
2184 -- constituent at the end of the package body declarations.
2190 procedure Adjust_Decl is
2192 while Present (Prev (Decl))
2193 and then Nkind (Decl) = N_Implicit_Label_Declaration
2199 ---------------------------
2200 -- Check_Entry_Contracts --
2201 ---------------------------
2203 procedure Check_Entry_Contracts is
2209 Ent := First_Entity (Current_Scope);
2210 while Present (Ent) loop
2212 -- This only concerns entries with pre/postconditions
2214 if Ekind (Ent) = E_Entry
2215 and then Present (Contract (Ent))
2216 and then Present (Pre_Post_Conditions (Contract (Ent)))
2218 ASN := Pre_Post_Conditions (Contract (Ent));
2220 Install_Formals (Ent);
2222 -- Pre/postconditions are rewritten as Check pragmas. Analysis
2223 -- is performed on a copy of the pragma expression, to prevent
2224 -- modifying the original expression.
2226 while Present (ASN) loop
2227 if Nkind (ASN) = N_Pragma then
2231 (First (Pragma_Argument_Associations (ASN))));
2232 Set_Parent (Exp, ASN);
2234 -- ??? why not Preanalyze_Assert_Expression
2239 ASN := Next_Pragma (ASN);
2247 end Check_Entry_Contracts;
2249 --------------------------------------
2250 -- Handle_Late_Controlled_Primitive --
2251 --------------------------------------
2253 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2254 Body_Spec : constant Node_Id := Specification (Body_Decl);
2255 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2256 Loc : constant Source_Ptr := Sloc (Body_Id);
2257 Params : constant List_Id :=
2258 Parameter_Specifications (Body_Spec);
2260 Spec_Id : Entity_Id;
2264 -- Consider only procedure bodies whose name matches one of the three
2265 -- controlled primitives.
2267 if Nkind (Body_Spec) /= N_Procedure_Specification
2268 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2274 -- A controlled primitive must have exactly one formal which is not
2275 -- an anonymous access type.
2277 elsif List_Length (Params) /= 1 then
2281 Typ := Parameter_Type (First (Params));
2283 if Nkind (Typ) = N_Access_Definition then
2289 -- The type of the formal must be derived from [Limited_]Controlled
2291 if not Is_Controlled (Entity (Typ)) then
2295 -- Check whether a specification exists for this body. We do not
2296 -- analyze the spec of the body in full, because it will be analyzed
2297 -- again when the body is properly analyzed, and we cannot create
2298 -- duplicate entries in the formals chain. We look for an explicit
2299 -- specification because the body may be an overriding operation and
2300 -- an inherited spec may be present.
2302 Spec_Id := Current_Entity (Body_Id);
2304 while Present (Spec_Id) loop
2305 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2306 and then Scope (Spec_Id) = Current_Scope
2307 and then Present (First_Formal (Spec_Id))
2308 and then No (Next_Formal (First_Formal (Spec_Id)))
2309 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2310 and then Comes_From_Source (Spec_Id)
2315 Spec_Id := Homonym (Spec_Id);
2318 -- At this point the body is known to be a late controlled primitive.
2319 -- Generate a matching spec and insert it before the body. Note the
2320 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2321 -- tree in this case.
2323 Spec := Copy_Separate_Tree (Body_Spec);
2325 -- Ensure that the subprogram declaration does not inherit the null
2326 -- indicator from the body as we now have a proper spec/body pair.
2328 Set_Null_Present (Spec, False);
2330 -- Ensure that the freeze node is inserted after the declaration of
2331 -- the primitive since its expansion will freeze the primitive.
2333 Decl := Make_Subprogram_Declaration (Loc, Specification => Spec);
2335 Insert_Before_And_Analyze (Body_Decl, Decl);
2336 end Handle_Late_Controlled_Primitive;
2338 --------------------------------
2339 -- Remove_Visible_Refinements --
2340 --------------------------------
2342 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2343 State_Elmt : Elmt_Id;
2345 if Present (Abstract_States (Spec_Id)) then
2346 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2347 while Present (State_Elmt) loop
2348 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2349 Next_Elmt (State_Elmt);
2352 end Remove_Visible_Refinements;
2356 Context : Node_Id := Empty;
2357 Freeze_From : Entity_Id := Empty;
2358 Next_Decl : Node_Id;
2360 Body_Seen : Boolean := False;
2361 -- Flag set when the first body [stub] is encountered
2363 -- Start of processing for Analyze_Declarations
2366 if Restriction_Check_Required (SPARK_05) then
2367 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2371 while Present (Decl) loop
2373 -- Package spec cannot contain a package declaration in SPARK
2375 if Nkind (Decl) = N_Package_Declaration
2376 and then Nkind (Parent (L)) = N_Package_Specification
2378 Check_SPARK_05_Restriction
2379 ("package specification cannot contain a package declaration",
2383 -- Complete analysis of declaration
2386 Next_Decl := Next (Decl);
2388 if No (Freeze_From) then
2389 Freeze_From := First_Entity (Current_Scope);
2392 -- At the end of a declarative part, freeze remaining entities
2393 -- declared in it. The end of the visible declarations of package
2394 -- specification is not the end of a declarative part if private
2395 -- declarations are present. The end of a package declaration is a
2396 -- freezing point only if it a library package. A task definition or
2397 -- protected type definition is not a freeze point either. Finally,
2398 -- we do not freeze entities in generic scopes, because there is no
2399 -- code generated for them and freeze nodes will be generated for
2402 -- The end of a package instantiation is not a freeze point, but
2403 -- for now we make it one, because the generic body is inserted
2404 -- (currently) immediately after. Generic instantiations will not
2405 -- be a freeze point once delayed freezing of bodies is implemented.
2406 -- (This is needed in any case for early instantiations ???).
2408 if No (Next_Decl) then
2409 if Nkind (Parent (L)) = N_Component_List then
2412 elsif Nkind_In (Parent (L), N_Protected_Definition,
2415 Check_Entry_Contracts;
2417 elsif Nkind (Parent (L)) /= N_Package_Specification then
2418 if Nkind (Parent (L)) = N_Package_Body then
2419 Freeze_From := First_Entity (Current_Scope);
2422 -- There may have been several freezing points previously,
2423 -- for example object declarations or subprogram bodies, but
2424 -- at the end of a declarative part we check freezing from
2425 -- the beginning, even though entities may already be frozen,
2426 -- in order to perform visibility checks on delayed aspects.
2429 Freeze_All (First_Entity (Current_Scope), Decl);
2430 Freeze_From := Last_Entity (Current_Scope);
2432 elsif Scope (Current_Scope) /= Standard_Standard
2433 and then not Is_Child_Unit (Current_Scope)
2434 and then No (Generic_Parent (Parent (L)))
2438 elsif L /= Visible_Declarations (Parent (L))
2439 or else No (Private_Declarations (Parent (L)))
2440 or else Is_Empty_List (Private_Declarations (Parent (L)))
2443 Freeze_All (First_Entity (Current_Scope), Decl);
2444 Freeze_From := Last_Entity (Current_Scope);
2446 -- At the end of the visible declarations the expressions in
2447 -- aspects of all entities declared so far must be resolved.
2448 -- The entities themselves might be frozen later, and the
2449 -- generated pragmas and attribute definition clauses analyzed
2450 -- in full at that point, but name resolution must take place
2452 -- In addition to being the proper semantics, this is mandatory
2453 -- within generic units, because global name capture requires
2454 -- those expressions to be analyzed, given that the generated
2455 -- pragmas do not appear in the original generic tree.
2457 elsif Serious_Errors_Detected = 0 then
2462 E := First_Entity (Current_Scope);
2463 while Present (E) loop
2464 Resolve_Aspect_Expressions (E);
2470 -- If next node is a body then freeze all types before the body.
2471 -- An exception occurs for some expander-generated bodies. If these
2472 -- are generated at places where in general language rules would not
2473 -- allow a freeze point, then we assume that the expander has
2474 -- explicitly checked that all required types are properly frozen,
2475 -- and we do not cause general freezing here. This special circuit
2476 -- is used when the encountered body is marked as having already
2479 -- In all other cases (bodies that come from source, and expander
2480 -- generated bodies that have not been analyzed yet), freeze all
2481 -- types now. Note that in the latter case, the expander must take
2482 -- care to attach the bodies at a proper place in the tree so as to
2483 -- not cause unwanted freezing at that point.
2485 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2487 -- When a controlled type is frozen, the expander generates stream
2488 -- and controlled type support routines. If the freeze is caused
2489 -- by the stand alone body of Initialize, Adjust and Finalize, the
2490 -- expander will end up using the wrong version of these routines
2491 -- as the body has not been processed yet. To remedy this, detect
2492 -- a late controlled primitive and create a proper spec for it.
2493 -- This ensures that the primitive will override its inherited
2494 -- counterpart before the freeze takes place.
2496 -- If the declaration we just processed is a body, do not attempt
2497 -- to examine Next_Decl as the late primitive idiom can only apply
2498 -- to the first encountered body.
2500 -- The spec of the late primitive is not generated in ASIS mode to
2501 -- ensure a consistent list of primitives that indicates the true
2502 -- semantic structure of the program (which is not relevant when
2503 -- generating executable code.
2505 -- ??? a cleaner approach may be possible and/or this solution
2506 -- could be extended to general-purpose late primitives, TBD.
2508 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2512 if Nkind (Next_Decl) = N_Subprogram_Body then
2513 Handle_Late_Controlled_Primitive (Next_Decl);
2518 Freeze_All (Freeze_From, Decl);
2519 Freeze_From := Last_Entity (Current_Scope);
2525 -- Analyze the contracts of packages and their bodies
2528 Context := Parent (L);
2530 if Nkind (Context) = N_Package_Specification then
2532 -- When a package has private declarations, its contract must be
2533 -- analyzed at the end of the said declarations. This way both the
2534 -- analysis and freeze actions are properly synchronized in case
2535 -- of private type use within the contract.
2537 if L = Private_Declarations (Context) then
2538 Analyze_Package_Contract (Defining_Entity (Context));
2540 -- Build the bodies of the default initial condition procedures
2541 -- for all types subject to pragma Default_Initial_Condition.
2542 -- From a purely Ada stand point, this is a freezing activity,
2543 -- however freezing is not available under GNATprove_Mode. To
2544 -- accomodate both scenarios, the bodies are build at the end
2545 -- of private declaration analysis.
2547 Build_Default_Init_Cond_Procedure_Bodies (L);
2549 -- Otherwise the contract is analyzed at the end of the visible
2552 elsif L = Visible_Declarations (Context)
2553 and then No (Private_Declarations (Context))
2555 Analyze_Package_Contract (Defining_Entity (Context));
2558 elsif Nkind (Context) = N_Package_Body then
2559 Analyze_Package_Body_Contract (Defining_Entity (Context));
2562 -- Analyze the contracts of various constructs now due to the delayed
2563 -- visibility needs of their aspects and pragmas.
2565 Analyze_Contracts (L);
2567 if Nkind (Context) = N_Package_Body then
2569 -- Ensure that all abstract states and objects declared in the
2570 -- state space of a package body are utilized as constituents.
2572 Check_Unused_Body_States (Defining_Entity (Context));
2574 -- State refinements are visible up to the end of the package body
2575 -- declarations. Hide the state refinements from visibility to
2576 -- restore the original state conditions.
2578 Remove_Visible_Refinements (Corresponding_Spec (Context));
2581 -- Verify that all abstract states found in any package declared in
2582 -- the input declarative list have proper refinements. The check is
2583 -- performed only when the context denotes a block, entry, package,
2584 -- protected, subprogram, or task body (SPARK RM 7.2.2(3)).
2586 Check_State_Refinements (Context);
2588 end Analyze_Declarations;
2590 -----------------------------------
2591 -- Analyze_Full_Type_Declaration --
2592 -----------------------------------
2594 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2595 Def : constant Node_Id := Type_Definition (N);
2596 Def_Id : constant Entity_Id := Defining_Identifier (N);
2600 Is_Remote : constant Boolean :=
2601 (Is_Remote_Types (Current_Scope)
2602 or else Is_Remote_Call_Interface (Current_Scope))
2603 and then not (In_Private_Part (Current_Scope)
2604 or else In_Package_Body (Current_Scope));
2606 procedure Check_Nonoverridable_Aspects;
2607 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2608 -- be overridden, and can only be confirmed on derivation.
2610 procedure Check_Ops_From_Incomplete_Type;
2611 -- If there is a tagged incomplete partial view of the type, traverse
2612 -- the primitives of the incomplete view and change the type of any
2613 -- controlling formals and result to indicate the full view. The
2614 -- primitives will be added to the full type's primitive operations
2615 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2616 -- is called from Process_Incomplete_Dependents).
2618 ----------------------------------
2619 -- Check_Nonoverridable_Aspects --
2620 ----------------------------------
2622 procedure Check_Nonoverridable_Aspects is
2623 Prev_Aspects : constant List_Id :=
2624 Aspect_Specifications (Parent (Def_Id));
2625 Par_Type : Entity_Id;
2627 function Has_Aspect_Spec
2629 Aspect_Name : Name_Id) return Boolean;
2630 -- Check whether a list of aspect specifications includes an entry
2631 -- for a specific aspect. The list is either that of a partial or
2634 ---------------------
2635 -- Has_Aspect_Spec --
2636 ---------------------
2638 function Has_Aspect_Spec
2640 Aspect_Name : Name_Id) return Boolean
2644 Spec := First (Specs);
2645 while Present (Spec) loop
2646 if Chars (Identifier (Spec)) = Aspect_Name then
2652 end Has_Aspect_Spec;
2654 -- Start of processing for Check_Nonoverridable_Aspects
2658 -- Get parent type of derived type. Note that Prev is the entity
2659 -- in the partial declaration, but its contents are now those of
2660 -- full view, while Def_Id reflects the partial view.
2662 if Is_Private_Type (Def_Id) then
2663 Par_Type := Etype (Full_View (Def_Id));
2665 Par_Type := Etype (Def_Id);
2668 -- If there is an inherited Implicit_Dereference, verify that it is
2669 -- made explicit in the partial view.
2671 if Has_Discriminants (Base_Type (Par_Type))
2672 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2673 and then Present (Discriminant_Specifications (Parent (Prev)))
2674 and then Present (Get_Reference_Discriminant (Par_Type))
2677 not Has_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference)
2680 ("type does not inherit implicit dereference", Prev);
2683 -- If one of the views has the aspect specified, verify that it
2684 -- is consistent with that of the parent.
2687 Par_Discr : constant Entity_Id :=
2688 Get_Reference_Discriminant (Par_Type);
2689 Cur_Discr : constant Entity_Id :=
2690 Get_Reference_Discriminant (Prev);
2692 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2693 Error_Msg_N ("aspect incosistent with that of parent", N);
2699 -- TBD : other nonoverridable aspects.
2700 end Check_Nonoverridable_Aspects;
2702 ------------------------------------
2703 -- Check_Ops_From_Incomplete_Type --
2704 ------------------------------------
2706 procedure Check_Ops_From_Incomplete_Type is
2713 and then Ekind (Prev) = E_Incomplete_Type
2714 and then Is_Tagged_Type (Prev)
2715 and then Is_Tagged_Type (T)
2717 Elmt := First_Elmt (Primitive_Operations (Prev));
2718 while Present (Elmt) loop
2721 Formal := First_Formal (Op);
2722 while Present (Formal) loop
2723 if Etype (Formal) = Prev then
2724 Set_Etype (Formal, T);
2727 Next_Formal (Formal);
2730 if Etype (Op) = Prev then
2737 end Check_Ops_From_Incomplete_Type;
2739 -- Start of processing for Analyze_Full_Type_Declaration
2742 Prev := Find_Type_Name (N);
2744 -- The full view, if present, now points to the current type. If there
2745 -- is an incomplete partial view, set a link to it, to simplify the
2746 -- retrieval of primitive operations of the type.
2748 -- Ada 2005 (AI-50217): If the type was previously decorated when
2749 -- imported through a LIMITED WITH clause, it appears as incomplete
2750 -- but has no full view.
2752 if Ekind (Prev) = E_Incomplete_Type
2753 and then Present (Full_View (Prev))
2755 T := Full_View (Prev);
2756 Set_Incomplete_View (N, Parent (Prev));
2761 Set_Is_Pure (T, Is_Pure (Current_Scope));
2763 -- We set the flag Is_First_Subtype here. It is needed to set the
2764 -- corresponding flag for the Implicit class-wide-type created
2765 -- during tagged types processing.
2767 Set_Is_First_Subtype (T, True);
2769 -- Only composite types other than array types are allowed to have
2774 -- For derived types, the rule will be checked once we've figured
2775 -- out the parent type.
2777 when N_Derived_Type_Definition =>
2780 -- For record types, discriminants are allowed, unless we are in
2783 when N_Record_Definition =>
2784 if Present (Discriminant_Specifications (N)) then
2785 Check_SPARK_05_Restriction
2786 ("discriminant type is not allowed",
2788 (First (Discriminant_Specifications (N))));
2792 if Present (Discriminant_Specifications (N)) then
2794 ("elementary or array type cannot have discriminants",
2796 (First (Discriminant_Specifications (N))));
2800 -- Elaborate the type definition according to kind, and generate
2801 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2802 -- already done (this happens during the reanalysis that follows a call
2803 -- to the high level optimizer).
2805 if not Analyzed (T) then
2809 when N_Access_To_Subprogram_Definition =>
2810 Access_Subprogram_Declaration (T, Def);
2812 -- If this is a remote access to subprogram, we must create the
2813 -- equivalent fat pointer type, and related subprograms.
2816 Process_Remote_AST_Declaration (N);
2819 -- Validate categorization rule against access type declaration
2820 -- usually a violation in Pure unit, Shared_Passive unit.
2822 Validate_Access_Type_Declaration (T, N);
2824 when N_Access_To_Object_Definition =>
2825 Access_Type_Declaration (T, Def);
2827 -- Validate categorization rule against access type declaration
2828 -- usually a violation in Pure unit, Shared_Passive unit.
2830 Validate_Access_Type_Declaration (T, N);
2832 -- If we are in a Remote_Call_Interface package and define a
2833 -- RACW, then calling stubs and specific stream attributes
2837 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2839 Add_RACW_Features (Def_Id);
2842 when N_Array_Type_Definition =>
2843 Array_Type_Declaration (T, Def);
2845 when N_Derived_Type_Definition =>
2846 Derived_Type_Declaration (T, N, T /= Def_Id);
2848 when N_Enumeration_Type_Definition =>
2849 Enumeration_Type_Declaration (T, Def);
2851 when N_Floating_Point_Definition =>
2852 Floating_Point_Type_Declaration (T, Def);
2854 when N_Decimal_Fixed_Point_Definition =>
2855 Decimal_Fixed_Point_Type_Declaration (T, Def);
2857 when N_Ordinary_Fixed_Point_Definition =>
2858 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2860 when N_Signed_Integer_Type_Definition =>
2861 Signed_Integer_Type_Declaration (T, Def);
2863 when N_Modular_Type_Definition =>
2864 Modular_Type_Declaration (T, Def);
2866 when N_Record_Definition =>
2867 Record_Type_Declaration (T, N, Prev);
2869 -- If declaration has a parse error, nothing to elaborate.
2875 raise Program_Error;
2880 if Etype (T) = Any_Type then
2884 -- Controlled type is not allowed in SPARK
2886 if Is_Visibly_Controlled (T) then
2887 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2890 -- A type declared within a Ghost region is automatically Ghost
2891 -- (SPARK RM 6.9(2)).
2893 if Ghost_Mode > None then
2894 Set_Is_Ghost_Entity (T);
2897 -- Some common processing for all types
2899 Set_Depends_On_Private (T, Has_Private_Component (T));
2900 Check_Ops_From_Incomplete_Type;
2902 -- Both the declared entity, and its anonymous base type if one was
2903 -- created, need freeze nodes allocated.
2906 B : constant Entity_Id := Base_Type (T);
2909 -- In the case where the base type differs from the first subtype, we
2910 -- pre-allocate a freeze node, and set the proper link to the first
2911 -- subtype. Freeze_Entity will use this preallocated freeze node when
2912 -- it freezes the entity.
2914 -- This does not apply if the base type is a generic type, whose
2915 -- declaration is independent of the current derived definition.
2917 if B /= T and then not Is_Generic_Type (B) then
2918 Ensure_Freeze_Node (B);
2919 Set_First_Subtype_Link (Freeze_Node (B), T);
2922 -- A type that is imported through a limited_with clause cannot
2923 -- generate any code, and thus need not be frozen. However, an access
2924 -- type with an imported designated type needs a finalization list,
2925 -- which may be referenced in some other package that has non-limited
2926 -- visibility on the designated type. Thus we must create the
2927 -- finalization list at the point the access type is frozen, to
2928 -- prevent unsatisfied references at link time.
2930 if not From_Limited_With (T) or else Is_Access_Type (T) then
2931 Set_Has_Delayed_Freeze (T);
2935 -- Case where T is the full declaration of some private type which has
2936 -- been swapped in Defining_Identifier (N).
2938 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2939 Process_Full_View (N, T, Def_Id);
2941 -- Record the reference. The form of this is a little strange, since
2942 -- the full declaration has been swapped in. So the first parameter
2943 -- here represents the entity to which a reference is made which is
2944 -- the "real" entity, i.e. the one swapped in, and the second
2945 -- parameter provides the reference location.
2947 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2948 -- since we don't want a complaint about the full type being an
2949 -- unwanted reference to the private type
2952 B : constant Boolean := Has_Pragma_Unreferenced (T);
2954 Set_Has_Pragma_Unreferenced (T, False);
2955 Generate_Reference (T, T, 'c');
2956 Set_Has_Pragma_Unreferenced (T, B);
2959 Set_Completion_Referenced (Def_Id);
2961 -- For completion of incomplete type, process incomplete dependents
2962 -- and always mark the full type as referenced (it is the incomplete
2963 -- type that we get for any real reference).
2965 elsif Ekind (Prev) = E_Incomplete_Type then
2966 Process_Incomplete_Dependents (N, T, Prev);
2967 Generate_Reference (Prev, Def_Id, 'c');
2968 Set_Completion_Referenced (Def_Id);
2970 -- If not private type or incomplete type completion, this is a real
2971 -- definition of a new entity, so record it.
2974 Generate_Definition (Def_Id);
2977 -- Propagate any pending access types whose finalization masters need to
2978 -- be fully initialized from the partial to the full view. Guard against
2979 -- an illegal full view that remains unanalyzed.
2981 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
2982 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
2985 if Chars (Scope (Def_Id)) = Name_System
2986 and then Chars (Def_Id) = Name_Address
2987 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2989 Set_Is_Descendant_Of_Address (Def_Id);
2990 Set_Is_Descendant_Of_Address (Base_Type (Def_Id));
2991 Set_Is_Descendant_Of_Address (Prev);
2994 Set_Optimize_Alignment_Flags (Def_Id);
2995 Check_Eliminated (Def_Id);
2997 -- If the declaration is a completion and aspects are present, apply
2998 -- them to the entity for the type which is currently the partial
2999 -- view, but which is the one that will be frozen.
3001 if Has_Aspects (N) then
3003 -- In most cases the partial view is a private type, and both views
3004 -- appear in different declarative parts. In the unusual case where
3005 -- the partial view is incomplete, perform the analysis on the
3006 -- full view, to prevent freezing anomalies with the corresponding
3007 -- class-wide type, which otherwise might be frozen before the
3008 -- dispatch table is built.
3011 and then Ekind (Prev) /= E_Incomplete_Type
3013 Analyze_Aspect_Specifications (N, Prev);
3018 Analyze_Aspect_Specifications (N, Def_Id);
3022 if Is_Derived_Type (Prev)
3023 and then Def_Id /= Prev
3025 Check_Nonoverridable_Aspects;
3027 end Analyze_Full_Type_Declaration;
3029 ----------------------------------
3030 -- Analyze_Incomplete_Type_Decl --
3031 ----------------------------------
3033 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3034 F : constant Boolean := Is_Pure (Current_Scope);
3038 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3040 Generate_Definition (Defining_Identifier (N));
3042 -- Process an incomplete declaration. The identifier must not have been
3043 -- declared already in the scope. However, an incomplete declaration may
3044 -- appear in the private part of a package, for a private type that has
3045 -- already been declared.
3047 -- In this case, the discriminants (if any) must match
3049 T := Find_Type_Name (N);
3051 Set_Ekind (T, E_Incomplete_Type);
3052 Init_Size_Align (T);
3053 Set_Is_First_Subtype (T, True);
3056 -- An incomplete type declared within a Ghost region is automatically
3057 -- Ghost (SPARK RM 6.9(2)).
3059 if Ghost_Mode > None then
3060 Set_Is_Ghost_Entity (T);
3063 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3064 -- incomplete types.
3066 if Tagged_Present (N) then
3067 Set_Is_Tagged_Type (T, True);
3068 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3069 Make_Class_Wide_Type (T);
3070 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3073 Set_Stored_Constraint (T, No_Elist);
3075 if Present (Discriminant_Specifications (N)) then
3077 Process_Discriminants (N);
3081 -- If the type has discriminants, nontrivial subtypes may be declared
3082 -- before the full view of the type. The full views of those subtypes
3083 -- will be built after the full view of the type.
3085 Set_Private_Dependents (T, New_Elmt_List);
3087 end Analyze_Incomplete_Type_Decl;
3089 -----------------------------------
3090 -- Analyze_Interface_Declaration --
3091 -----------------------------------
3093 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3094 CW : constant Entity_Id := Class_Wide_Type (T);
3097 Set_Is_Tagged_Type (T);
3098 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3100 Set_Is_Limited_Record (T, Limited_Present (Def)
3101 or else Task_Present (Def)
3102 or else Protected_Present (Def)
3103 or else Synchronized_Present (Def));
3105 -- Type is abstract if full declaration carries keyword, or if previous
3106 -- partial view did.
3108 Set_Is_Abstract_Type (T);
3109 Set_Is_Interface (T);
3111 -- Type is a limited interface if it includes the keyword limited, task,
3112 -- protected, or synchronized.
3114 Set_Is_Limited_Interface
3115 (T, Limited_Present (Def)
3116 or else Protected_Present (Def)
3117 or else Synchronized_Present (Def)
3118 or else Task_Present (Def));
3120 Set_Interfaces (T, New_Elmt_List);
3121 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3123 -- Complete the decoration of the class-wide entity if it was already
3124 -- built (i.e. during the creation of the limited view)
3126 if Present (CW) then
3127 Set_Is_Interface (CW);
3128 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3131 -- Check runtime support for synchronized interfaces
3133 if (Is_Task_Interface (T)
3134 or else Is_Protected_Interface (T)
3135 or else Is_Synchronized_Interface (T))
3136 and then not RTE_Available (RE_Select_Specific_Data)
3138 Error_Msg_CRT ("synchronized interfaces", T);
3140 end Analyze_Interface_Declaration;
3142 -----------------------------
3143 -- Analyze_Itype_Reference --
3144 -----------------------------
3146 -- Nothing to do. This node is placed in the tree only for the benefit of
3147 -- back end processing, and has no effect on the semantic processing.
3149 procedure Analyze_Itype_Reference (N : Node_Id) is
3151 pragma Assert (Is_Itype (Itype (N)));
3153 end Analyze_Itype_Reference;
3155 --------------------------------
3156 -- Analyze_Number_Declaration --
3157 --------------------------------
3159 procedure Analyze_Number_Declaration (N : Node_Id) is
3160 E : constant Node_Id := Expression (N);
3161 Id : constant Entity_Id := Defining_Identifier (N);
3162 Index : Interp_Index;
3167 Generate_Definition (Id);
3170 -- A number declared within a Ghost region is automatically Ghost
3171 -- (SPARK RM 6.9(2)).
3173 if Ghost_Mode > None then
3174 Set_Is_Ghost_Entity (Id);
3177 -- This is an optimization of a common case of an integer literal
3179 if Nkind (E) = N_Integer_Literal then
3180 Set_Is_Static_Expression (E, True);
3181 Set_Etype (E, Universal_Integer);
3183 Set_Etype (Id, Universal_Integer);
3184 Set_Ekind (Id, E_Named_Integer);
3185 Set_Is_Frozen (Id, True);
3189 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3191 -- Process expression, replacing error by integer zero, to avoid
3192 -- cascaded errors or aborts further along in the processing
3194 -- Replace Error by integer zero, which seems least likely to cause
3198 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3199 Set_Error_Posted (E);
3204 -- Verify that the expression is static and numeric. If
3205 -- the expression is overloaded, we apply the preference
3206 -- rule that favors root numeric types.
3208 if not Is_Overloaded (E) then
3210 if Has_Dynamic_Predicate_Aspect (T) then
3212 ("subtype has dynamic predicate, "
3213 & "not allowed in number declaration", N);
3219 Get_First_Interp (E, Index, It);
3220 while Present (It.Typ) loop
3221 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3222 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3224 if T = Any_Type then
3227 elsif It.Typ = Universal_Real
3229 It.Typ = Universal_Integer
3231 -- Choose universal interpretation over any other
3238 Get_Next_Interp (Index, It);
3242 if Is_Integer_Type (T) then
3244 Set_Etype (Id, Universal_Integer);
3245 Set_Ekind (Id, E_Named_Integer);
3247 elsif Is_Real_Type (T) then
3249 -- Because the real value is converted to universal_real, this is a
3250 -- legal context for a universal fixed expression.
3252 if T = Universal_Fixed then
3254 Loc : constant Source_Ptr := Sloc (N);
3255 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3257 New_Occurrence_Of (Universal_Real, Loc),
3258 Expression => Relocate_Node (E));
3265 elsif T = Any_Fixed then
3266 Error_Msg_N ("illegal context for mixed mode operation", E);
3268 -- Expression is of the form : universal_fixed * integer. Try to
3269 -- resolve as universal_real.
3271 T := Universal_Real;
3276 Set_Etype (Id, Universal_Real);
3277 Set_Ekind (Id, E_Named_Real);
3280 Wrong_Type (E, Any_Numeric);
3284 Set_Ekind (Id, E_Constant);
3285 Set_Never_Set_In_Source (Id, True);
3286 Set_Is_True_Constant (Id, True);
3290 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3291 Set_Etype (E, Etype (Id));
3294 if not Is_OK_Static_Expression (E) then
3295 Flag_Non_Static_Expr
3296 ("non-static expression used in number declaration!", E);
3297 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3298 Set_Etype (E, Any_Type);
3301 Analyze_Dimension (N);
3302 end Analyze_Number_Declaration;
3304 --------------------------------
3305 -- Analyze_Object_Declaration --
3306 --------------------------------
3308 procedure Analyze_Object_Declaration (N : Node_Id) is
3309 Loc : constant Source_Ptr := Sloc (N);
3310 Id : constant Entity_Id := Defining_Identifier (N);
3314 E : Node_Id := Expression (N);
3315 -- E is set to Expression (N) throughout this routine. When
3316 -- Expression (N) is modified, E is changed accordingly.
3318 Prev_Entity : Entity_Id := Empty;
3320 function Count_Tasks (T : Entity_Id) return Uint;
3321 -- This function is called when a non-generic library level object of a
3322 -- task type is declared. Its function is to count the static number of
3323 -- tasks declared within the type (it is only called if Has_Task is set
3324 -- for T). As a side effect, if an array of tasks with non-static bounds
3325 -- or a variant record type is encountered, Check_Restriction is called
3326 -- indicating the count is unknown.
3328 function Delayed_Aspect_Present return Boolean;
3329 -- If the declaration has an expression that is an aggregate, and it
3330 -- has aspects that require delayed analysis, the resolution of the
3331 -- aggregate must be deferred to the freeze point of the objet. This
3332 -- special processing was created for address clauses, but it must
3333 -- also apply to Alignment. This must be done before the aspect
3334 -- specifications are analyzed because we must handle the aggregate
3335 -- before the analysis of the object declaration is complete.
3337 -- Any other relevant delayed aspects on object declarations ???
3343 function Count_Tasks (T : Entity_Id) return Uint is
3349 if Is_Task_Type (T) then
3352 elsif Is_Record_Type (T) then
3353 if Has_Discriminants (T) then
3354 Check_Restriction (Max_Tasks, N);
3359 C := First_Component (T);
3360 while Present (C) loop
3361 V := V + Count_Tasks (Etype (C));
3368 elsif Is_Array_Type (T) then
3369 X := First_Index (T);
3370 V := Count_Tasks (Component_Type (T));
3371 while Present (X) loop
3374 if not Is_OK_Static_Subtype (C) then
3375 Check_Restriction (Max_Tasks, N);
3378 V := V * (UI_Max (Uint_0,
3379 Expr_Value (Type_High_Bound (C)) -
3380 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3393 ----------------------------
3394 -- Delayed_Aspect_Present --
3395 ----------------------------
3397 function Delayed_Aspect_Present return Boolean is
3402 if Present (Aspect_Specifications (N)) then
3403 A := First (Aspect_Specifications (N));
3404 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3405 while Present (A) loop
3406 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3415 end Delayed_Aspect_Present;
3419 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
3420 Related_Id : Entity_Id;
3422 -- Start of processing for Analyze_Object_Declaration
3425 -- There are three kinds of implicit types generated by an
3426 -- object declaration:
3428 -- 1. Those generated by the original Object Definition
3430 -- 2. Those generated by the Expression
3432 -- 3. Those used to constrain the Object Definition with the
3433 -- expression constraints when the definition is unconstrained.
3435 -- They must be generated in this order to avoid order of elaboration
3436 -- issues. Thus the first step (after entering the name) is to analyze
3437 -- the object definition.
3439 if Constant_Present (N) then
3440 Prev_Entity := Current_Entity_In_Scope (Id);
3442 if Present (Prev_Entity)
3444 -- If the homograph is an implicit subprogram, it is overridden
3445 -- by the current declaration.
3447 ((Is_Overloadable (Prev_Entity)
3448 and then Is_Inherited_Operation (Prev_Entity))
3450 -- The current object is a discriminal generated for an entry
3451 -- family index. Even though the index is a constant, in this
3452 -- particular context there is no true constant redeclaration.
3453 -- Enter_Name will handle the visibility.
3456 (Is_Discriminal (Id)
3457 and then Ekind (Discriminal_Link (Id)) =
3458 E_Entry_Index_Parameter)
3460 -- The current object is the renaming for a generic declared
3461 -- within the instance.
3464 (Ekind (Prev_Entity) = E_Package
3465 and then Nkind (Parent (Prev_Entity)) =
3466 N_Package_Renaming_Declaration
3467 and then not Comes_From_Source (Prev_Entity)
3469 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3471 Prev_Entity := Empty;
3475 -- The object declaration is Ghost when it is subject to pragma Ghost or
3476 -- completes a deferred Ghost constant. Set the mode now to ensure that
3477 -- any nodes generated during analysis and expansion are properly marked
3480 Set_Ghost_Mode (N, Prev_Entity);
3482 if Present (Prev_Entity) then
3483 Constant_Redeclaration (Id, N, T);
3485 Generate_Reference (Prev_Entity, Id, 'c');
3486 Set_Completion_Referenced (Id);
3488 if Error_Posted (N) then
3490 -- Type mismatch or illegal redeclaration; do not analyze
3491 -- expression to avoid cascaded errors.
3493 T := Find_Type_Of_Object (Object_Definition (N), N);
3495 Set_Ekind (Id, E_Variable);
3499 -- In the normal case, enter identifier at the start to catch premature
3500 -- usage in the initialization expression.
3503 Generate_Definition (Id);
3506 Mark_Coextensions (N, Object_Definition (N));
3508 T := Find_Type_Of_Object (Object_Definition (N), N);
3510 if Nkind (Object_Definition (N)) = N_Access_Definition
3512 (Access_To_Subprogram_Definition (Object_Definition (N)))
3513 and then Protected_Present
3514 (Access_To_Subprogram_Definition (Object_Definition (N)))
3516 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3519 if Error_Posted (Id) then
3521 Set_Ekind (Id, E_Variable);
3526 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3527 -- out some static checks.
3529 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3531 -- In case of aggregates we must also take care of the correct
3532 -- initialization of nested aggregates bug this is done at the
3533 -- point of the analysis of the aggregate (see sem_aggr.adb) ???
3535 if Present (Expression (N))
3536 and then Nkind (Expression (N)) = N_Aggregate
3542 Save_Typ : constant Entity_Id := Etype (Id);
3544 Set_Etype (Id, T); -- Temp. decoration for static checks
3545 Null_Exclusion_Static_Checks (N);
3546 Set_Etype (Id, Save_Typ);
3551 -- Object is marked pure if it is in a pure scope
3553 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3555 -- If deferred constant, make sure context is appropriate. We detect
3556 -- a deferred constant as a constant declaration with no expression.
3557 -- A deferred constant can appear in a package body if its completion
3558 -- is by means of an interface pragma.
3560 if Constant_Present (N) and then No (E) then
3562 -- A deferred constant may appear in the declarative part of the
3563 -- following constructs:
3567 -- extended return statements
3570 -- subprogram bodies
3573 -- When declared inside a package spec, a deferred constant must be
3574 -- completed by a full constant declaration or pragma Import. In all
3575 -- other cases, the only proper completion is pragma Import. Extended
3576 -- return statements are flagged as invalid contexts because they do
3577 -- not have a declarative part and so cannot accommodate the pragma.
3579 if Ekind (Current_Scope) = E_Return_Statement then
3581 ("invalid context for deferred constant declaration (RM 7.4)",
3584 ("\declaration requires an initialization expression",
3586 Set_Constant_Present (N, False);
3588 -- In Ada 83, deferred constant must be of private type
3590 elsif not Is_Private_Type (T) then
3591 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3593 ("(Ada 83) deferred constant must be private type", N);
3597 -- If not a deferred constant, then the object declaration freezes
3598 -- its type, unless the object is of an anonymous type and has delayed
3599 -- aspects. In that case the type is frozen when the object itself is.
3602 Check_Fully_Declared (T, N);
3604 if Has_Delayed_Aspects (Id)
3605 and then Is_Array_Type (T)
3606 and then Is_Itype (T)
3608 Set_Has_Delayed_Freeze (T);
3610 Freeze_Before (N, T);
3614 -- If the object was created by a constrained array definition, then
3615 -- set the link in both the anonymous base type and anonymous subtype
3616 -- that are built to represent the array type to point to the object.
3618 if Nkind (Object_Definition (Declaration_Node (Id))) =
3619 N_Constrained_Array_Definition
3621 Set_Related_Array_Object (T, Id);
3622 Set_Related_Array_Object (Base_Type (T), Id);
3625 -- Special checks for protected objects not at library level
3627 if Has_Protected (T) and then not Is_Library_Level_Entity (Id) then
3628 Check_Restriction (No_Local_Protected_Objects, Id);
3630 -- Protected objects with interrupt handlers must be at library level
3632 -- Ada 2005: This test is not needed (and the corresponding clause
3633 -- in the RM is removed) because accessibility checks are sufficient
3634 -- to make handlers not at the library level illegal.
3636 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3637 -- applies to the '95 version of the language as well.
3639 if Is_Protected_Type (T)
3640 and then Has_Interrupt_Handler (T)
3641 and then Ada_Version < Ada_95
3644 ("interrupt object can only be declared at library level", Id);
3648 -- Check for violation of No_Local_Timing_Events
3650 if Has_Timing_Event (T) and then not Is_Library_Level_Entity (Id) then
3651 Check_Restriction (No_Local_Timing_Events, Id);
3654 -- The actual subtype of the object is the nominal subtype, unless
3655 -- the nominal one is unconstrained and obtained from the expression.
3659 -- These checks should be performed before the initialization expression
3660 -- is considered, so that the Object_Definition node is still the same
3661 -- as in source code.
3663 -- In SPARK, the nominal subtype is always given by a subtype mark
3664 -- and must not be unconstrained. (The only exception to this is the
3665 -- acceptance of declarations of constants of type String.)
3667 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3669 Check_SPARK_05_Restriction
3670 ("subtype mark required", Object_Definition (N));
3672 elsif Is_Array_Type (T)
3673 and then not Is_Constrained (T)
3674 and then T /= Standard_String
3676 Check_SPARK_05_Restriction
3677 ("subtype mark of constrained type expected",
3678 Object_Definition (N));
3681 -- There are no aliased objects in SPARK
3683 if Aliased_Present (N) then
3684 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3687 -- Process initialization expression if present and not in error
3689 if Present (E) and then E /= Error then
3691 -- Generate an error in case of CPP class-wide object initialization.
3692 -- Required because otherwise the expansion of the class-wide
3693 -- assignment would try to use 'size to initialize the object
3694 -- (primitive that is not available in CPP tagged types).
3696 if Is_Class_Wide_Type (Act_T)
3698 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3700 (Present (Full_View (Root_Type (Etype (Act_T))))
3702 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3705 ("predefined assignment not available for 'C'P'P tagged types",
3709 Mark_Coextensions (N, E);
3712 -- In case of errors detected in the analysis of the expression,
3713 -- decorate it with the expected type to avoid cascaded errors
3715 if No (Etype (E)) then
3719 -- If an initialization expression is present, then we set the
3720 -- Is_True_Constant flag. It will be reset if this is a variable
3721 -- and it is indeed modified.
3723 Set_Is_True_Constant (Id, True);
3725 -- If we are analyzing a constant declaration, set its completion
3726 -- flag after analyzing and resolving the expression.
3728 if Constant_Present (N) then
3729 Set_Has_Completion (Id);
3732 -- Set type and resolve (type may be overridden later on). Note:
3733 -- Ekind (Id) must still be E_Void at this point so that incorrect
3734 -- early usage within E is properly diagnosed.
3738 -- If the expression is an aggregate we must look ahead to detect
3739 -- the possible presence of an address clause, and defer resolution
3740 -- and expansion of the aggregate to the freeze point of the entity.
3742 -- This is not always legal because the aggregate may contain other
3743 -- references that need freezing, e.g. references to other entities
3744 -- with address clauses. In any case, when compiling with -gnatI the
3745 -- presence of the address clause must be ignored.
3747 if Comes_From_Source (N)
3748 and then Expander_Active
3749 and then Nkind (E) = N_Aggregate
3751 ((Present (Following_Address_Clause (N))
3752 and then not Ignore_Rep_Clauses)
3753 or else Delayed_Aspect_Present)
3761 -- No further action needed if E is a call to an inlined function
3762 -- which returns an unconstrained type and it has been expanded into
3763 -- a procedure call. In that case N has been replaced by an object
3764 -- declaration without initializing expression and it has been
3765 -- analyzed (see Expand_Inlined_Call).
3767 if Back_End_Inlining
3768 and then Expander_Active
3769 and then Nkind (E) = N_Function_Call
3770 and then Nkind (Name (E)) in N_Has_Entity
3771 and then Is_Inlined (Entity (Name (E)))
3772 and then not Is_Constrained (Etype (E))
3773 and then Analyzed (N)
3774 and then No (Expression (N))
3776 Ghost_Mode := Save_Ghost_Mode;
3780 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3781 -- node (which was marked already-analyzed), we need to set the type
3782 -- to something other than Any_Access in order to keep gigi happy.
3784 if Etype (E) = Any_Access then
3788 -- If the object is an access to variable, the initialization
3789 -- expression cannot be an access to constant.
3791 if Is_Access_Type (T)
3792 and then not Is_Access_Constant (T)
3793 and then Is_Access_Type (Etype (E))
3794 and then Is_Access_Constant (Etype (E))
3797 ("access to variable cannot be initialized with an "
3798 & "access-to-constant expression", E);
3801 if not Assignment_OK (N) then
3802 Check_Initialization (T, E);
3805 Check_Unset_Reference (E);
3807 -- If this is a variable, then set current value. If this is a
3808 -- declared constant of a scalar type with a static expression,
3809 -- indicate that it is always valid.
3811 if not Constant_Present (N) then
3812 if Compile_Time_Known_Value (E) then
3813 Set_Current_Value (Id, E);
3816 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3817 Set_Is_Known_Valid (Id);
3820 -- Deal with setting of null flags
3822 if Is_Access_Type (T) then
3823 if Known_Non_Null (E) then
3824 Set_Is_Known_Non_Null (Id, True);
3825 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3826 Set_Is_Known_Null (Id, True);
3830 -- Check incorrect use of dynamically tagged expressions
3832 if Is_Tagged_Type (T) then
3833 Check_Dynamically_Tagged_Expression
3839 Apply_Scalar_Range_Check (E, T);
3840 Apply_Static_Length_Check (E, T);
3842 if Nkind (Original_Node (N)) = N_Object_Declaration
3843 and then Comes_From_Source (Original_Node (N))
3845 -- Only call test if needed
3847 and then Restriction_Check_Required (SPARK_05)
3848 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3850 Check_SPARK_05_Restriction
3851 ("initialization expression is not appropriate", E);
3854 -- A formal parameter of a specific tagged type whose related
3855 -- subprogram is subject to pragma Extensions_Visible with value
3856 -- "False" cannot be implicitly converted to a class-wide type by
3857 -- means of an initialization expression (SPARK RM 6.1.7(3)). Do
3858 -- not consider internally generated expressions.
3860 if Is_Class_Wide_Type (T)
3861 and then Comes_From_Source (E)
3862 and then Is_EVF_Expression (E)
3865 ("formal parameter cannot be implicitly converted to "
3866 & "class-wide type when Extensions_Visible is False", E);
3870 -- If the No_Streams restriction is set, check that the type of the
3871 -- object is not, and does not contain, any subtype derived from
3872 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3873 -- Has_Stream just for efficiency reasons. There is no point in
3874 -- spending time on a Has_Stream check if the restriction is not set.
3876 if Restriction_Check_Required (No_Streams) then
3877 if Has_Stream (T) then
3878 Check_Restriction (No_Streams, N);
3882 -- Deal with predicate check before we start to do major rewriting. It
3883 -- is OK to initialize and then check the initialized value, since the
3884 -- object goes out of scope if we get a predicate failure. Note that we
3885 -- do this in the analyzer and not the expander because the analyzer
3886 -- does some substantial rewriting in some cases.
3888 -- We need a predicate check if the type has predicates that are not
3889 -- ignored, and if either there is an initializing expression, or for
3890 -- default initialization when we have at least one case of an explicit
3891 -- default initial value and then this is not an internal declaration
3892 -- whose initialization comes later (as for an aggregate expansion).
3894 if not Suppress_Assignment_Checks (N)
3895 and then Present (Predicate_Function (T))
3896 and then not Predicates_Ignored (T)
3897 and then not No_Initialization (N)
3901 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3903 -- If the type has a static predicate and the expression is known at
3904 -- compile time, see if the expression satisfies the predicate.
3907 Check_Expression_Against_Static_Predicate (E, T);
3910 -- If the type is a null record and there is no explicit initial
3911 -- expression, no predicate check applies.
3913 if No (E) and then Is_Null_Record_Type (T) then
3918 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3922 -- Case of unconstrained type
3924 if not Is_Definite_Subtype (T) then
3926 -- In SPARK, a declaration of unconstrained type is allowed
3927 -- only for constants of type string.
3929 if Is_String_Type (T) and then not Constant_Present (N) then
3930 Check_SPARK_05_Restriction
3931 ("declaration of object of unconstrained type not allowed", N);
3934 -- Nothing to do in deferred constant case
3936 if Constant_Present (N) and then No (E) then
3939 -- Case of no initialization present
3942 if No_Initialization (N) then
3945 elsif Is_Class_Wide_Type (T) then
3947 ("initialization required in class-wide declaration ", N);
3951 ("unconstrained subtype not allowed (need initialization)",
3952 Object_Definition (N));
3954 if Is_Record_Type (T) and then Has_Discriminants (T) then
3956 ("\provide initial value or explicit discriminant values",
3957 Object_Definition (N));
3960 ("\or give default discriminant values for type&",
3961 Object_Definition (N), T);
3963 elsif Is_Array_Type (T) then
3965 ("\provide initial value or explicit array bounds",
3966 Object_Definition (N));
3970 -- Case of initialization present but in error. Set initial
3971 -- expression as absent (but do not make above complaints)
3973 elsif E = Error then
3974 Set_Expression (N, Empty);
3977 -- Case of initialization present
3980 -- Check restrictions in Ada 83
3982 if not Constant_Present (N) then
3984 -- Unconstrained variables not allowed in Ada 83 mode
3986 if Ada_Version = Ada_83
3987 and then Comes_From_Source (Object_Definition (N))
3990 ("(Ada 83) unconstrained variable not allowed",
3991 Object_Definition (N));
3995 -- Now we constrain the variable from the initializing expression
3997 -- If the expression is an aggregate, it has been expanded into
3998 -- individual assignments. Retrieve the actual type from the
3999 -- expanded construct.
4001 if Is_Array_Type (T)
4002 and then No_Initialization (N)
4003 and then Nkind (Original_Node (E)) = N_Aggregate
4007 -- In case of class-wide interface object declarations we delay
4008 -- the generation of the equivalent record type declarations until
4009 -- its expansion because there are cases in they are not required.
4011 elsif Is_Interface (T) then
4014 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
4015 -- we should prevent the generation of another Itype with the
4016 -- same name as the one already generated, or we end up with
4017 -- two identical types in GNATprove.
4019 elsif GNATprove_Mode then
4022 -- If the type is an unchecked union, no subtype can be built from
4023 -- the expression. Rewrite declaration as a renaming, which the
4024 -- back-end can handle properly. This is a rather unusual case,
4025 -- because most unchecked_union declarations have default values
4026 -- for discriminants and are thus not indefinite.
4028 elsif Is_Unchecked_Union (T) then
4029 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4030 Set_Ekind (Id, E_Constant);
4032 Set_Ekind (Id, E_Variable);
4035 -- An object declared within a Ghost region is automatically
4036 -- Ghost (SPARK RM 6.9(2)).
4038 if Ghost_Mode > None then
4039 Set_Is_Ghost_Entity (Id);
4041 -- The Ghost policy in effect at the point of declaration
4042 -- and at the point of completion must match
4043 -- (SPARK RM 6.9(14)).
4045 if Present (Prev_Entity)
4046 and then Is_Ghost_Entity (Prev_Entity)
4048 Check_Ghost_Completion (Prev_Entity, Id);
4053 Make_Object_Renaming_Declaration (Loc,
4054 Defining_Identifier => Id,
4055 Subtype_Mark => New_Occurrence_Of (T, Loc),
4058 Set_Renamed_Object (Id, E);
4059 Freeze_Before (N, T);
4062 Ghost_Mode := Save_Ghost_Mode;
4066 -- Ensure that the generated subtype has a unique external name
4067 -- when the related object is public. This guarantees that the
4068 -- subtype and its bounds will not be affected by switches or
4069 -- pragmas that may offset the internal counter due to extra
4072 if Is_Public (Id) then
4075 Related_Id := Empty;
4078 Expand_Subtype_From_Expr
4081 Subtype_Indic => Object_Definition (N),
4083 Related_Id => Related_Id);
4085 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4088 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4090 if Aliased_Present (N) then
4091 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4094 Freeze_Before (N, Act_T);
4095 Freeze_Before (N, T);
4098 elsif Is_Array_Type (T)
4099 and then No_Initialization (N)
4100 and then (Nkind (Original_Node (E)) = N_Aggregate
4101 or else (Nkind (Original_Node (E)) = N_Qualified_Expression
4102 and then Nkind (Original_Node (Expression
4103 (Original_Node (E)))) = N_Aggregate))
4105 if not Is_Entity_Name (Object_Definition (N)) then
4107 Check_Compile_Time_Size (Act_T);
4109 if Aliased_Present (N) then
4110 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4114 -- When the given object definition and the aggregate are specified
4115 -- independently, and their lengths might differ do a length check.
4116 -- This cannot happen if the aggregate is of the form (others =>...)
4118 if not Is_Constrained (T) then
4121 elsif Nkind (E) = N_Raise_Constraint_Error then
4123 -- Aggregate is statically illegal. Place back in declaration
4125 Set_Expression (N, E);
4126 Set_No_Initialization (N, False);
4128 elsif T = Etype (E) then
4131 elsif Nkind (E) = N_Aggregate
4132 and then Present (Component_Associations (E))
4133 and then Present (Choices (First (Component_Associations (E))))
4134 and then Nkind (First
4135 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4140 Apply_Length_Check (E, T);
4143 -- If the type is limited unconstrained with defaulted discriminants and
4144 -- there is no expression, then the object is constrained by the
4145 -- defaults, so it is worthwhile building the corresponding subtype.
4147 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4148 and then not Is_Constrained (T)
4149 and then Has_Discriminants (T)
4152 Act_T := Build_Default_Subtype (T, N);
4154 -- Ada 2005: A limited object may be initialized by means of an
4155 -- aggregate. If the type has default discriminants it has an
4156 -- unconstrained nominal type, Its actual subtype will be obtained
4157 -- from the aggregate, and not from the default discriminants.
4162 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4164 elsif Nkind (E) = N_Function_Call
4165 and then Constant_Present (N)
4166 and then Has_Unconstrained_Elements (Etype (E))
4168 -- The back-end has problems with constants of a discriminated type
4169 -- with defaults, if the initial value is a function call. We
4170 -- generate an intermediate temporary that will receive a reference
4171 -- to the result of the call. The initialization expression then
4172 -- becomes a dereference of that temporary.
4174 Remove_Side_Effects (E);
4176 -- If this is a constant declaration of an unconstrained type and
4177 -- the initialization is an aggregate, we can use the subtype of the
4178 -- aggregate for the declared entity because it is immutable.
4180 elsif not Is_Constrained (T)
4181 and then Has_Discriminants (T)
4182 and then Constant_Present (N)
4183 and then not Has_Unchecked_Union (T)
4184 and then Nkind (E) = N_Aggregate
4189 -- Check No_Wide_Characters restriction
4191 Check_Wide_Character_Restriction (T, Object_Definition (N));
4193 -- Indicate this is not set in source. Certainly true for constants, and
4194 -- true for variables so far (will be reset for a variable if and when
4195 -- we encounter a modification in the source).
4197 Set_Never_Set_In_Source (Id);
4199 -- Now establish the proper kind and type of the object
4201 if Constant_Present (N) then
4202 Set_Ekind (Id, E_Constant);
4203 Set_Is_True_Constant (Id);
4206 Set_Ekind (Id, E_Variable);
4208 -- A variable is set as shared passive if it appears in a shared
4209 -- passive package, and is at the outer level. This is not done for
4210 -- entities generated during expansion, because those are always
4211 -- manipulated locally.
4213 if Is_Shared_Passive (Current_Scope)
4214 and then Is_Library_Level_Entity (Id)
4215 and then Comes_From_Source (Id)
4217 Set_Is_Shared_Passive (Id);
4218 Check_Shared_Var (Id, T, N);
4221 -- Set Has_Initial_Value if initializing expression present. Note
4222 -- that if there is no initializing expression, we leave the state
4223 -- of this flag unchanged (usually it will be False, but notably in
4224 -- the case of exception choice variables, it will already be true).
4227 Set_Has_Initial_Value (Id);
4231 -- Initialize alignment and size and capture alignment setting
4233 Init_Alignment (Id);
4235 Set_Optimize_Alignment_Flags (Id);
4237 -- An object declared within a Ghost region is automatically Ghost
4238 -- (SPARK RM 6.9(2)).
4240 if Ghost_Mode > None
4241 or else (Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity))
4243 Set_Is_Ghost_Entity (Id);
4245 -- The Ghost policy in effect at the point of declaration and at the
4246 -- point of completion must match (SPARK RM 6.9(14)).
4248 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4249 Check_Ghost_Completion (Prev_Entity, Id);
4253 -- Deal with aliased case
4255 if Aliased_Present (N) then
4256 Set_Is_Aliased (Id);
4258 -- If the object is aliased and the type is unconstrained with
4259 -- defaulted discriminants and there is no expression, then the
4260 -- object is constrained by the defaults, so it is worthwhile
4261 -- building the corresponding subtype.
4263 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4264 -- unconstrained, then only establish an actual subtype if the
4265 -- nominal subtype is indefinite. In definite cases the object is
4266 -- unconstrained in Ada 2005.
4269 and then Is_Record_Type (T)
4270 and then not Is_Constrained (T)
4271 and then Has_Discriminants (T)
4272 and then (Ada_Version < Ada_2005
4273 or else not Is_Definite_Subtype (T))
4275 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4279 -- Now we can set the type of the object
4281 Set_Etype (Id, Act_T);
4283 -- Non-constant object is marked to be treated as volatile if type is
4284 -- volatile and we clear the Current_Value setting that may have been
4285 -- set above. Doing so for constants isn't required and might interfere
4286 -- with possible uses of the object as a static expression in contexts
4287 -- incompatible with volatility (e.g. as a case-statement alternative).
4289 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4290 Set_Treat_As_Volatile (Id);
4291 Set_Current_Value (Id, Empty);
4294 -- Deal with controlled types
4296 if Has_Controlled_Component (Etype (Id))
4297 or else Is_Controlled (Etype (Id))
4299 if not Is_Library_Level_Entity (Id) then
4300 Check_Restriction (No_Nested_Finalization, N);
4302 Validate_Controlled_Object (Id);
4306 if Has_Task (Etype (Id)) then
4307 Check_Restriction (No_Tasking, N);
4309 -- Deal with counting max tasks
4311 -- Nothing to do if inside a generic
4313 if Inside_A_Generic then
4316 -- If library level entity, then count tasks
4318 elsif Is_Library_Level_Entity (Id) then
4319 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4321 -- If not library level entity, then indicate we don't know max
4322 -- tasks and also check task hierarchy restriction and blocking
4323 -- operation (since starting a task is definitely blocking).
4326 Check_Restriction (Max_Tasks, N);
4327 Check_Restriction (No_Task_Hierarchy, N);
4328 Check_Potentially_Blocking_Operation (N);
4331 -- A rather specialized test. If we see two tasks being declared
4332 -- of the same type in the same object declaration, and the task
4333 -- has an entry with an address clause, we know that program error
4334 -- will be raised at run time since we can't have two tasks with
4335 -- entries at the same address.
4337 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4342 E := First_Entity (Etype (Id));
4343 while Present (E) loop
4344 if Ekind (E) = E_Entry
4345 and then Present (Get_Attribute_Definition_Clause
4346 (E, Attribute_Address))
4348 Error_Msg_Warn := SPARK_Mode /= On;
4350 ("more than one task with same entry address<<", N);
4351 Error_Msg_N ("\Program_Error [<<", N);
4353 Make_Raise_Program_Error (Loc,
4354 Reason => PE_Duplicated_Entry_Address));
4364 -- Some simple constant-propagation: if the expression is a constant
4365 -- string initialized with a literal, share the literal. This avoids
4369 and then Is_Entity_Name (E)
4370 and then Ekind (Entity (E)) = E_Constant
4371 and then Base_Type (Etype (E)) = Standard_String
4374 Val : constant Node_Id := Constant_Value (Entity (E));
4376 if Present (Val) and then Nkind (Val) = N_String_Literal then
4377 Rewrite (E, New_Copy (Val));
4382 -- Another optimization: if the nominal subtype is unconstrained and
4383 -- the expression is a function call that returns an unconstrained
4384 -- type, rewrite the declaration as a renaming of the result of the
4385 -- call. The exceptions below are cases where the copy is expected,
4386 -- either by the back end (Aliased case) or by the semantics, as for
4387 -- initializing controlled types or copying tags for classwide types.
4390 and then Nkind (E) = N_Explicit_Dereference
4391 and then Nkind (Original_Node (E)) = N_Function_Call
4392 and then not Is_Library_Level_Entity (Id)
4393 and then not Is_Constrained (Underlying_Type (T))
4394 and then not Is_Aliased (Id)
4395 and then not Is_Class_Wide_Type (T)
4396 and then not Is_Controlled_Active (T)
4397 and then not Has_Controlled_Component (Base_Type (T))
4398 and then Expander_Active
4401 Make_Object_Renaming_Declaration (Loc,
4402 Defining_Identifier => Id,
4403 Access_Definition => Empty,
4404 Subtype_Mark => New_Occurrence_Of
4405 (Base_Type (Etype (Id)), Loc),
4408 Set_Renamed_Object (Id, E);
4410 -- Force generation of debugging information for the constant and for
4411 -- the renamed function call.
4413 Set_Debug_Info_Needed (Id);
4414 Set_Debug_Info_Needed (Entity (Prefix (E)));
4417 if Present (Prev_Entity)
4418 and then Is_Frozen (Prev_Entity)
4419 and then not Error_Posted (Id)
4421 Error_Msg_N ("full constant declaration appears too late", N);
4424 Check_Eliminated (Id);
4426 -- Deal with setting In_Private_Part flag if in private part
4428 if Ekind (Scope (Id)) = E_Package
4429 and then In_Private_Part (Scope (Id))
4431 Set_In_Private_Part (Id);
4435 -- Initialize the refined state of a variable here because this is a
4436 -- common destination for legal and illegal object declarations.
4438 if Ekind (Id) = E_Variable then
4439 Set_Encapsulating_State (Id, Empty);
4442 if Has_Aspects (N) then
4443 Analyze_Aspect_Specifications (N, Id);
4446 Analyze_Dimension (N);
4448 -- Verify whether the object declaration introduces an illegal hidden
4449 -- state within a package subject to a null abstract state.
4451 if Ekind (Id) = E_Variable then
4452 Check_No_Hidden_State (Id);
4455 Ghost_Mode := Save_Ghost_Mode;
4456 end Analyze_Object_Declaration;
4458 ---------------------------
4459 -- Analyze_Others_Choice --
4460 ---------------------------
4462 -- Nothing to do for the others choice node itself, the semantic analysis
4463 -- of the others choice will occur as part of the processing of the parent
4465 procedure Analyze_Others_Choice (N : Node_Id) is
4466 pragma Warnings (Off, N);
4469 end Analyze_Others_Choice;
4471 -------------------------------------------
4472 -- Analyze_Private_Extension_Declaration --
4473 -------------------------------------------
4475 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4476 Indic : constant Node_Id := Subtype_Indication (N);
4477 T : constant Entity_Id := Defining_Identifier (N);
4479 Iface_Elmt : Elmt_Id;
4480 Parent_Base : Entity_Id;
4481 Parent_Type : Entity_Id;
4484 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4486 if Is_Non_Empty_List (Interface_List (N)) then
4492 Intf := First (Interface_List (N));
4493 while Present (Intf) loop
4494 T := Find_Type_Of_Subtype_Indic (Intf);
4496 Diagnose_Interface (Intf, T);
4502 Generate_Definition (T);
4504 -- For other than Ada 2012, just enter the name in the current scope
4506 if Ada_Version < Ada_2012 then
4509 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4510 -- case of private type that completes an incomplete type.
4517 Prev := Find_Type_Name (N);
4519 pragma Assert (Prev = T
4520 or else (Ekind (Prev) = E_Incomplete_Type
4521 and then Present (Full_View (Prev))
4522 and then Full_View (Prev) = T));
4526 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4527 Parent_Base := Base_Type (Parent_Type);
4529 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4530 Set_Ekind (T, Ekind (Parent_Type));
4531 Set_Etype (T, Any_Type);
4534 elsif not Is_Tagged_Type (Parent_Type) then
4536 ("parent of type extension must be a tagged type ", Indic);
4539 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4540 Error_Msg_N ("premature derivation of incomplete type", Indic);
4543 elsif Is_Concurrent_Type (Parent_Type) then
4545 ("parent type of a private extension cannot be a synchronized "
4546 & "tagged type (RM 3.9.1 (3/1))", N);
4548 Set_Etype (T, Any_Type);
4549 Set_Ekind (T, E_Limited_Private_Type);
4550 Set_Private_Dependents (T, New_Elmt_List);
4551 Set_Error_Posted (T);
4555 -- Perhaps the parent type should be changed to the class-wide type's
4556 -- specific type in this case to prevent cascading errors ???
4558 if Is_Class_Wide_Type (Parent_Type) then
4560 ("parent of type extension must not be a class-wide type", Indic);
4564 if (not Is_Package_Or_Generic_Package (Current_Scope)
4565 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4566 or else In_Private_Part (Current_Scope)
4568 Error_Msg_N ("invalid context for private extension", N);
4571 -- Set common attributes
4573 Set_Is_Pure (T, Is_Pure (Current_Scope));
4574 Set_Scope (T, Current_Scope);
4575 Set_Ekind (T, E_Record_Type_With_Private);
4576 Init_Size_Align (T);
4577 Set_Default_SSO (T);
4579 Set_Etype (T, Parent_Base);
4580 Propagate_Concurrent_Flags (T, Parent_Base);
4582 Set_Convention (T, Convention (Parent_Type));
4583 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4584 Set_Is_First_Subtype (T);
4585 Make_Class_Wide_Type (T);
4587 if Unknown_Discriminants_Present (N) then
4588 Set_Discriminant_Constraint (T, No_Elist);
4591 Build_Derived_Record_Type (N, Parent_Type, T);
4593 -- A private extension inherits any class-wide invariants coming from a
4594 -- parent type or an interface. Note that the invariant procedure of the
4595 -- parent type should not be inherited because the private extension may
4596 -- define invariants of its own.
4598 if Has_Inheritable_Invariants (Parent_Type) then
4599 Set_Has_Inherited_Invariants (T);
4601 elsif Present (Interfaces (T)) then
4602 Iface_Elmt := First_Elmt (Interfaces (T));
4603 while Present (Iface_Elmt) loop
4604 Iface := Node (Iface_Elmt);
4606 if Has_Inheritable_Invariants (Iface) then
4607 Set_Has_Inherited_Invariants (T);
4611 Next_Elmt (Iface_Elmt);
4615 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4616 -- synchronized formal derived type.
4618 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4619 Set_Is_Limited_Record (T);
4621 -- Formal derived type case
4623 if Is_Generic_Type (T) then
4625 -- The parent must be a tagged limited type or a synchronized
4628 if (not Is_Tagged_Type (Parent_Type)
4629 or else not Is_Limited_Type (Parent_Type))
4631 (not Is_Interface (Parent_Type)
4632 or else not Is_Synchronized_Interface (Parent_Type))
4635 ("parent type of & must be tagged limited or synchronized",
4639 -- The progenitors (if any) must be limited or synchronized
4642 if Present (Interfaces (T)) then
4643 Iface_Elmt := First_Elmt (Interfaces (T));
4644 while Present (Iface_Elmt) loop
4645 Iface := Node (Iface_Elmt);
4647 if not Is_Limited_Interface (Iface)
4648 and then not Is_Synchronized_Interface (Iface)
4651 ("progenitor & must be limited or synchronized",
4655 Next_Elmt (Iface_Elmt);
4659 -- Regular derived extension, the parent must be a limited or
4660 -- synchronized interface.
4663 if not Is_Interface (Parent_Type)
4664 or else (not Is_Limited_Interface (Parent_Type)
4665 and then not Is_Synchronized_Interface (Parent_Type))
4668 ("parent type of & must be limited interface", N, T);
4672 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4673 -- extension with a synchronized parent must be explicitly declared
4674 -- synchronized, because the full view will be a synchronized type.
4675 -- This must be checked before the check for limited types below,
4676 -- to ensure that types declared limited are not allowed to extend
4677 -- synchronized interfaces.
4679 elsif Is_Interface (Parent_Type)
4680 and then Is_Synchronized_Interface (Parent_Type)
4681 and then not Synchronized_Present (N)
4684 ("private extension of& must be explicitly synchronized",
4687 elsif Limited_Present (N) then
4688 Set_Is_Limited_Record (T);
4690 if not Is_Limited_Type (Parent_Type)
4692 (not Is_Interface (Parent_Type)
4693 or else not Is_Limited_Interface (Parent_Type))
4695 Error_Msg_NE ("parent type& of limited extension must be limited",
4701 if Has_Aspects (N) then
4702 Analyze_Aspect_Specifications (N, T);
4704 end Analyze_Private_Extension_Declaration;
4706 ---------------------------------
4707 -- Analyze_Subtype_Declaration --
4708 ---------------------------------
4710 procedure Analyze_Subtype_Declaration
4712 Skip : Boolean := False)
4714 Id : constant Entity_Id := Defining_Identifier (N);
4715 R_Checks : Check_Result;
4719 Generate_Definition (Id);
4720 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4721 Init_Size_Align (Id);
4723 -- The following guard condition on Enter_Name is to handle cases where
4724 -- the defining identifier has already been entered into the scope but
4725 -- the declaration as a whole needs to be analyzed.
4727 -- This case in particular happens for derived enumeration types. The
4728 -- derived enumeration type is processed as an inserted enumeration type
4729 -- declaration followed by a rewritten subtype declaration. The defining
4730 -- identifier, however, is entered into the name scope very early in the
4731 -- processing of the original type declaration and therefore needs to be
4732 -- avoided here, when the created subtype declaration is analyzed. (See
4733 -- Build_Derived_Types)
4735 -- This also happens when the full view of a private type is derived
4736 -- type with constraints. In this case the entity has been introduced
4737 -- in the private declaration.
4739 -- Finally this happens in some complex cases when validity checks are
4740 -- enabled, where the same subtype declaration may be analyzed twice.
4741 -- This can happen if the subtype is created by the pre-analysis of
4742 -- an attribute tht gives the range of a loop statement, and the loop
4743 -- itself appears within an if_statement that will be rewritten during
4747 or else (Present (Etype (Id))
4748 and then (Is_Private_Type (Etype (Id))
4749 or else Is_Task_Type (Etype (Id))
4750 or else Is_Rewrite_Substitution (N)))
4754 elsif Current_Entity (Id) = Id then
4761 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4763 -- Class-wide equivalent types of records with unknown discriminants
4764 -- involve the generation of an itype which serves as the private view
4765 -- of a constrained record subtype. In such cases the base type of the
4766 -- current subtype we are processing is the private itype. Use the full
4767 -- of the private itype when decorating various attributes.
4770 and then Is_Private_Type (T)
4771 and then Present (Full_View (T))
4776 -- Inherit common attributes
4778 Set_Is_Volatile (Id, Is_Volatile (T));
4779 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4780 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4781 Set_Convention (Id, Convention (T));
4783 -- If ancestor has predicates then so does the subtype, and in addition
4784 -- we must delay the freeze to properly arrange predicate inheritance.
4786 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4787 -- in which T = ID, so the above tests and assignments do nothing???
4789 if Has_Predicates (T)
4790 or else (Present (Ancestor_Subtype (T))
4791 and then Has_Predicates (Ancestor_Subtype (T)))
4793 Set_Has_Predicates (Id);
4794 Set_Has_Delayed_Freeze (Id);
4797 -- Subtype of Boolean cannot have a constraint in SPARK
4799 if Is_Boolean_Type (T)
4800 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4802 Check_SPARK_05_Restriction
4803 ("subtype of Boolean cannot have constraint", N);
4806 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4808 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4814 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4815 One_Cstr := First (Constraints (Cstr));
4816 while Present (One_Cstr) loop
4818 -- Index or discriminant constraint in SPARK must be a
4822 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4824 Check_SPARK_05_Restriction
4825 ("subtype mark required", One_Cstr);
4827 -- String subtype must have a lower bound of 1 in SPARK.
4828 -- Note that we do not need to test for the non-static case
4829 -- here, since that was already taken care of in
4830 -- Process_Range_Expr_In_Decl.
4832 elsif Base_Type (T) = Standard_String then
4833 Get_Index_Bounds (One_Cstr, Low, High);
4835 if Is_OK_Static_Expression (Low)
4836 and then Expr_Value (Low) /= 1
4838 Check_SPARK_05_Restriction
4839 ("String subtype must have lower bound of 1", N);
4849 -- In the case where there is no constraint given in the subtype
4850 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4851 -- semantic attributes must be established here.
4853 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4854 Set_Etype (Id, Base_Type (T));
4856 -- Subtype of unconstrained array without constraint is not allowed
4859 if Is_Array_Type (T) and then not Is_Constrained (T) then
4860 Check_SPARK_05_Restriction
4861 ("subtype of unconstrained array must have constraint", N);
4866 Set_Ekind (Id, E_Array_Subtype);
4867 Copy_Array_Subtype_Attributes (Id, T);
4869 when Decimal_Fixed_Point_Kind =>
4870 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4871 Set_Digits_Value (Id, Digits_Value (T));
4872 Set_Delta_Value (Id, Delta_Value (T));
4873 Set_Scale_Value (Id, Scale_Value (T));
4874 Set_Small_Value (Id, Small_Value (T));
4875 Set_Scalar_Range (Id, Scalar_Range (T));
4876 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4877 Set_Is_Constrained (Id, Is_Constrained (T));
4878 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4879 Set_RM_Size (Id, RM_Size (T));
4881 when Enumeration_Kind =>
4882 Set_Ekind (Id, E_Enumeration_Subtype);
4883 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4884 Set_Scalar_Range (Id, Scalar_Range (T));
4885 Set_Is_Character_Type (Id, Is_Character_Type (T));
4886 Set_Is_Constrained (Id, Is_Constrained (T));
4887 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4888 Set_RM_Size (Id, RM_Size (T));
4889 Inherit_Predicate_Flags (Id, T);
4891 when Ordinary_Fixed_Point_Kind =>
4892 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4893 Set_Scalar_Range (Id, Scalar_Range (T));
4894 Set_Small_Value (Id, Small_Value (T));
4895 Set_Delta_Value (Id, Delta_Value (T));
4896 Set_Is_Constrained (Id, Is_Constrained (T));
4897 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4898 Set_RM_Size (Id, RM_Size (T));
4901 Set_Ekind (Id, E_Floating_Point_Subtype);
4902 Set_Scalar_Range (Id, Scalar_Range (T));
4903 Set_Digits_Value (Id, Digits_Value (T));
4904 Set_Is_Constrained (Id, Is_Constrained (T));
4906 -- If the floating point type has dimensions, these will be
4907 -- inherited subsequently when Analyze_Dimensions is called.
4909 when Signed_Integer_Kind =>
4910 Set_Ekind (Id, E_Signed_Integer_Subtype);
4911 Set_Scalar_Range (Id, Scalar_Range (T));
4912 Set_Is_Constrained (Id, Is_Constrained (T));
4913 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4914 Set_RM_Size (Id, RM_Size (T));
4915 Inherit_Predicate_Flags (Id, T);
4917 when Modular_Integer_Kind =>
4918 Set_Ekind (Id, E_Modular_Integer_Subtype);
4919 Set_Scalar_Range (Id, Scalar_Range (T));
4920 Set_Is_Constrained (Id, Is_Constrained (T));
4921 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4922 Set_RM_Size (Id, RM_Size (T));
4923 Inherit_Predicate_Flags (Id, T);
4925 when Class_Wide_Kind =>
4926 Set_Ekind (Id, E_Class_Wide_Subtype);
4927 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4928 Set_Cloned_Subtype (Id, T);
4929 Set_Is_Tagged_Type (Id, True);
4930 Set_Has_Unknown_Discriminants
4932 Set_No_Tagged_Streams_Pragma
4933 (Id, No_Tagged_Streams_Pragma (T));
4935 if Ekind (T) = E_Class_Wide_Subtype then
4936 Set_Equivalent_Type (Id, Equivalent_Type (T));
4939 when E_Record_Type | E_Record_Subtype =>
4940 Set_Ekind (Id, E_Record_Subtype);
4942 if Ekind (T) = E_Record_Subtype
4943 and then Present (Cloned_Subtype (T))
4945 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4947 Set_Cloned_Subtype (Id, T);
4950 Set_First_Entity (Id, First_Entity (T));
4951 Set_Last_Entity (Id, Last_Entity (T));
4952 Set_Has_Discriminants (Id, Has_Discriminants (T));
4953 Set_Is_Constrained (Id, Is_Constrained (T));
4954 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4955 Set_Has_Implicit_Dereference
4956 (Id, Has_Implicit_Dereference (T));
4957 Set_Has_Unknown_Discriminants
4958 (Id, Has_Unknown_Discriminants (T));
4960 if Has_Discriminants (T) then
4961 Set_Discriminant_Constraint
4962 (Id, Discriminant_Constraint (T));
4963 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4965 elsif Has_Unknown_Discriminants (Id) then
4966 Set_Discriminant_Constraint (Id, No_Elist);
4969 if Is_Tagged_Type (T) then
4970 Set_Is_Tagged_Type (Id, True);
4971 Set_No_Tagged_Streams_Pragma
4972 (Id, No_Tagged_Streams_Pragma (T));
4973 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4974 Set_Direct_Primitive_Operations
4975 (Id, Direct_Primitive_Operations (T));
4976 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4978 if Is_Interface (T) then
4979 Set_Is_Interface (Id);
4980 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4984 when Private_Kind =>
4985 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4986 Set_Has_Discriminants (Id, Has_Discriminants (T));
4987 Set_Is_Constrained (Id, Is_Constrained (T));
4988 Set_First_Entity (Id, First_Entity (T));
4989 Set_Last_Entity (Id, Last_Entity (T));
4990 Set_Private_Dependents (Id, New_Elmt_List);
4991 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4992 Set_Has_Implicit_Dereference
4993 (Id, Has_Implicit_Dereference (T));
4994 Set_Has_Unknown_Discriminants
4995 (Id, Has_Unknown_Discriminants (T));
4996 Set_Known_To_Have_Preelab_Init
4997 (Id, Known_To_Have_Preelab_Init (T));
4999 if Is_Tagged_Type (T) then
5000 Set_Is_Tagged_Type (Id);
5001 Set_No_Tagged_Streams_Pragma (Id,
5002 No_Tagged_Streams_Pragma (T));
5003 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5004 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5005 Set_Direct_Primitive_Operations (Id,
5006 Direct_Primitive_Operations (T));
5009 -- In general the attributes of the subtype of a private type
5010 -- are the attributes of the partial view of parent. However,
5011 -- the full view may be a discriminated type, and the subtype
5012 -- must share the discriminant constraint to generate correct
5013 -- calls to initialization procedures.
5015 if Has_Discriminants (T) then
5016 Set_Discriminant_Constraint
5017 (Id, Discriminant_Constraint (T));
5018 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5020 elsif Present (Full_View (T))
5021 and then Has_Discriminants (Full_View (T))
5023 Set_Discriminant_Constraint
5024 (Id, Discriminant_Constraint (Full_View (T)));
5025 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5027 -- This would seem semantically correct, but apparently
5028 -- generates spurious errors about missing components ???
5030 -- Set_Has_Discriminants (Id);
5033 Prepare_Private_Subtype_Completion (Id, N);
5035 -- If this is the subtype of a constrained private type with
5036 -- discriminants that has got a full view and we also have
5037 -- built a completion just above, show that the completion
5038 -- is a clone of the full view to the back-end.
5040 if Has_Discriminants (T)
5041 and then not Has_Unknown_Discriminants (T)
5042 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5043 and then Present (Full_View (T))
5044 and then Present (Full_View (Id))
5046 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5050 Set_Ekind (Id, E_Access_Subtype);
5051 Set_Is_Constrained (Id, Is_Constrained (T));
5052 Set_Is_Access_Constant
5053 (Id, Is_Access_Constant (T));
5054 Set_Directly_Designated_Type
5055 (Id, Designated_Type (T));
5056 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5058 -- A Pure library_item must not contain the declaration of a
5059 -- named access type, except within a subprogram, generic
5060 -- subprogram, task unit, or protected unit, or if it has
5061 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5063 if Comes_From_Source (Id)
5064 and then In_Pure_Unit
5065 and then not In_Subprogram_Task_Protected_Unit
5066 and then not No_Pool_Assigned (Id)
5069 ("named access types not allowed in pure unit", N);
5072 when Concurrent_Kind =>
5073 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5074 Set_Corresponding_Record_Type (Id,
5075 Corresponding_Record_Type (T));
5076 Set_First_Entity (Id, First_Entity (T));
5077 Set_First_Private_Entity (Id, First_Private_Entity (T));
5078 Set_Has_Discriminants (Id, Has_Discriminants (T));
5079 Set_Is_Constrained (Id, Is_Constrained (T));
5080 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5081 Set_Last_Entity (Id, Last_Entity (T));
5083 if Is_Tagged_Type (T) then
5084 Set_No_Tagged_Streams_Pragma
5085 (Id, No_Tagged_Streams_Pragma (T));
5088 if Has_Discriminants (T) then
5089 Set_Discriminant_Constraint
5090 (Id, Discriminant_Constraint (T));
5091 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5094 when Incomplete_Kind =>
5095 if Ada_Version >= Ada_2005 then
5097 -- In Ada 2005 an incomplete type can be explicitly tagged:
5098 -- propagate indication. Note that we also have to include
5099 -- subtypes for Ada 2012 extended use of incomplete types.
5101 Set_Ekind (Id, E_Incomplete_Subtype);
5102 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5103 Set_Private_Dependents (Id, New_Elmt_List);
5105 if Is_Tagged_Type (Id) then
5106 Set_No_Tagged_Streams_Pragma
5107 (Id, No_Tagged_Streams_Pragma (T));
5108 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5111 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5112 -- incomplete type visible through a limited with clause.
5114 if From_Limited_With (T)
5115 and then Present (Non_Limited_View (T))
5117 Set_From_Limited_With (Id);
5118 Set_Non_Limited_View (Id, Non_Limited_View (T));
5120 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5121 -- to the private dependents of the original incomplete
5122 -- type for future transformation.
5125 Append_Elmt (Id, Private_Dependents (T));
5128 -- If the subtype name denotes an incomplete type an error
5129 -- was already reported by Process_Subtype.
5132 Set_Etype (Id, Any_Type);
5136 raise Program_Error;
5140 if Etype (Id) = Any_Type then
5144 -- Some common processing on all types
5146 Set_Size_Info (Id, T);
5147 Set_First_Rep_Item (Id, First_Rep_Item (T));
5149 -- If the parent type is a generic actual, so is the subtype. This may
5150 -- happen in a nested instance. Why Comes_From_Source test???
5152 if not Comes_From_Source (N) then
5153 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5156 -- If this is a subtype declaration for an actual in an instance,
5157 -- inherit static and dynamic predicates if any.
5159 -- If declaration has no aspect specifications, inherit predicate
5160 -- info as well. Unclear how to handle the case of both specified
5161 -- and inherited predicates ??? Other inherited aspects, such as
5162 -- invariants, should be OK, but the combination with later pragmas
5163 -- may also require special merging.
5165 if Has_Predicates (T)
5166 and then Present (Predicate_Function (T))
5168 ((In_Instance and then not Comes_From_Source (N))
5169 or else No (Aspect_Specifications (N)))
5171 Set_Subprograms_For_Type (Id, Subprograms_For_Type (T));
5173 if Has_Static_Predicate (T) then
5174 Set_Has_Static_Predicate (Id);
5175 Set_Static_Discrete_Predicate (Id, Static_Discrete_Predicate (T));
5179 -- Propagate invariant-related attributes from the base type to the
5182 Propagate_Invariant_Attributes (Id, From_Typ => Base_Type (T));
5184 -- Remaining processing depends on characteristics of base type
5188 Set_Is_Immediately_Visible (Id, True);
5189 Set_Depends_On_Private (Id, Has_Private_Component (T));
5190 Set_Is_Descendant_Of_Address (Id, Is_Descendant_Of_Address (T));
5192 if Is_Interface (T) then
5193 Set_Is_Interface (Id);
5196 if Present (Generic_Parent_Type (N))
5198 (Nkind (Parent (Generic_Parent_Type (N))) /=
5199 N_Formal_Type_Declaration
5200 or else Nkind (Formal_Type_Definition
5201 (Parent (Generic_Parent_Type (N)))) /=
5202 N_Formal_Private_Type_Definition)
5204 if Is_Tagged_Type (Id) then
5206 -- If this is a generic actual subtype for a synchronized type,
5207 -- the primitive operations are those of the corresponding record
5208 -- for which there is a separate subtype declaration.
5210 if Is_Concurrent_Type (Id) then
5212 elsif Is_Class_Wide_Type (Id) then
5213 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5215 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5218 elsif Scope (Etype (Id)) /= Standard_Standard then
5219 Derive_Subprograms (Generic_Parent_Type (N), Id);
5223 if Is_Private_Type (T) and then Present (Full_View (T)) then
5224 Conditional_Delay (Id, Full_View (T));
5226 -- The subtypes of components or subcomponents of protected types
5227 -- do not need freeze nodes, which would otherwise appear in the
5228 -- wrong scope (before the freeze node for the protected type). The
5229 -- proper subtypes are those of the subcomponents of the corresponding
5232 elsif Ekind (Scope (Id)) /= E_Protected_Type
5233 and then Present (Scope (Scope (Id))) -- error defense
5234 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5236 Conditional_Delay (Id, T);
5239 -- Check that Constraint_Error is raised for a scalar subtype indication
5240 -- when the lower or upper bound of a non-null range lies outside the
5241 -- range of the type mark.
5243 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5244 if Is_Scalar_Type (Etype (Id))
5245 and then Scalar_Range (Id) /=
5247 (Etype (Subtype_Mark (Subtype_Indication (N))))
5251 Etype (Subtype_Mark (Subtype_Indication (N))));
5253 -- In the array case, check compatibility for each index
5255 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5257 -- This really should be a subprogram that finds the indications
5261 Subt_Index : Node_Id := First_Index (Id);
5262 Target_Index : Node_Id :=
5264 (Subtype_Mark (Subtype_Indication (N))));
5265 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5268 while Present (Subt_Index) loop
5269 if ((Nkind (Subt_Index) = N_Identifier
5270 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5271 or else Nkind (Subt_Index) = N_Subtype_Indication)
5273 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5276 Target_Typ : constant Entity_Id :=
5277 Etype (Target_Index);
5281 (Scalar_Range (Etype (Subt_Index)),
5284 Defining_Identifier (N));
5286 -- Reset Has_Dynamic_Range_Check on the subtype to
5287 -- prevent elision of the index check due to a dynamic
5288 -- check generated for a preceding index (needed since
5289 -- Insert_Range_Checks tries to avoid generating
5290 -- redundant checks on a given declaration).
5292 Set_Has_Dynamic_Range_Check (N, False);
5298 Sloc (Defining_Identifier (N)));
5300 -- Record whether this index involved a dynamic check
5303 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5307 Next_Index (Subt_Index);
5308 Next_Index (Target_Index);
5311 -- Finally, mark whether the subtype involves dynamic checks
5313 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5318 Set_Optimize_Alignment_Flags (Id);
5319 Check_Eliminated (Id);
5322 if Has_Aspects (N) then
5323 Analyze_Aspect_Specifications (N, Id);
5326 Analyze_Dimension (N);
5328 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5329 -- indications on composite types where the constraints are dynamic.
5330 -- Note that object declarations and aggregates generate implicit
5331 -- subtype declarations, which this covers. One special case is that the
5332 -- implicitly generated "=" for discriminated types includes an
5333 -- offending subtype declaration, which is harmless, so we ignore it
5336 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5338 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5340 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5341 and then not (Is_Internal (Id)
5342 and then Is_TSS (Scope (Id),
5343 TSS_Composite_Equality))
5344 and then not Within_Init_Proc
5345 and then not All_Composite_Constraints_Static (Cstr)
5347 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5351 end Analyze_Subtype_Declaration;
5353 --------------------------------
5354 -- Analyze_Subtype_Indication --
5355 --------------------------------
5357 procedure Analyze_Subtype_Indication (N : Node_Id) is
5358 T : constant Entity_Id := Subtype_Mark (N);
5359 R : constant Node_Id := Range_Expression (Constraint (N));
5366 Set_Etype (N, Etype (R));
5367 Resolve (R, Entity (T));
5369 Set_Error_Posted (R);
5370 Set_Error_Posted (T);
5372 end Analyze_Subtype_Indication;
5374 --------------------------
5375 -- Analyze_Variant_Part --
5376 --------------------------
5378 procedure Analyze_Variant_Part (N : Node_Id) is
5379 Discr_Name : Node_Id;
5380 Discr_Type : Entity_Id;
5382 procedure Process_Variant (A : Node_Id);
5383 -- Analyze declarations for a single variant
5385 package Analyze_Variant_Choices is
5386 new Generic_Analyze_Choices (Process_Variant);
5387 use Analyze_Variant_Choices;
5389 ---------------------
5390 -- Process_Variant --
5391 ---------------------
5393 procedure Process_Variant (A : Node_Id) is
5394 CL : constant Node_Id := Component_List (A);
5396 if not Null_Present (CL) then
5397 Analyze_Declarations (Component_Items (CL));
5399 if Present (Variant_Part (CL)) then
5400 Analyze (Variant_Part (CL));
5403 end Process_Variant;
5405 -- Start of processing for Analyze_Variant_Part
5408 Discr_Name := Name (N);
5409 Analyze (Discr_Name);
5411 -- If Discr_Name bad, get out (prevent cascaded errors)
5413 if Etype (Discr_Name) = Any_Type then
5417 -- Check invalid discriminant in variant part
5419 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5420 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5423 Discr_Type := Etype (Entity (Discr_Name));
5425 if not Is_Discrete_Type (Discr_Type) then
5427 ("discriminant in a variant part must be of a discrete type",
5432 -- Now analyze the choices, which also analyzes the declarations that
5433 -- are associated with each choice.
5435 Analyze_Choices (Variants (N), Discr_Type);
5437 -- Note: we used to instantiate and call Check_Choices here to check
5438 -- that the choices covered the discriminant, but it's too early to do
5439 -- that because of statically predicated subtypes, whose analysis may
5440 -- be deferred to their freeze point which may be as late as the freeze
5441 -- point of the containing record. So this call is now to be found in
5442 -- Freeze_Record_Declaration.
5444 end Analyze_Variant_Part;
5446 ----------------------------
5447 -- Array_Type_Declaration --
5448 ----------------------------
5450 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5451 Component_Def : constant Node_Id := Component_Definition (Def);
5452 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5453 Element_Type : Entity_Id;
5454 Implicit_Base : Entity_Id;
5456 Related_Id : Entity_Id := Empty;
5458 P : constant Node_Id := Parent (Def);
5462 if Nkind (Def) = N_Constrained_Array_Definition then
5463 Index := First (Discrete_Subtype_Definitions (Def));
5465 Index := First (Subtype_Marks (Def));
5468 -- Find proper names for the implicit types which may be public. In case
5469 -- of anonymous arrays we use the name of the first object of that type
5473 Related_Id := Defining_Identifier (P);
5479 while Present (Index) loop
5482 -- Test for odd case of trying to index a type by the type itself
5484 if Is_Entity_Name (Index) and then Entity (Index) = T then
5485 Error_Msg_N ("type& cannot be indexed by itself", Index);
5486 Set_Entity (Index, Standard_Boolean);
5487 Set_Etype (Index, Standard_Boolean);
5490 -- Check SPARK restriction requiring a subtype mark
5492 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5493 Check_SPARK_05_Restriction ("subtype mark required", Index);
5496 -- Add a subtype declaration for each index of private array type
5497 -- declaration whose etype is also private. For example:
5500 -- type Index is private;
5502 -- type Table is array (Index) of ...
5505 -- This is currently required by the expander for the internally
5506 -- generated equality subprogram of records with variant parts in
5507 -- which the etype of some component is such private type.
5509 if Ekind (Current_Scope) = E_Package
5510 and then In_Private_Part (Current_Scope)
5511 and then Has_Private_Declaration (Etype (Index))
5514 Loc : constant Source_Ptr := Sloc (Def);
5519 New_E := Make_Temporary (Loc, 'T');
5520 Set_Is_Internal (New_E);
5523 Make_Subtype_Declaration (Loc,
5524 Defining_Identifier => New_E,
5525 Subtype_Indication =>
5526 New_Occurrence_Of (Etype (Index), Loc));
5528 Insert_Before (Parent (Def), Decl);
5530 Set_Etype (Index, New_E);
5532 -- If the index is a range the Entity attribute is not
5533 -- available. Example:
5536 -- type T is private;
5538 -- type T is new Natural;
5539 -- Table : array (T(1) .. T(10)) of Boolean;
5542 if Nkind (Index) /= N_Range then
5543 Set_Entity (Index, New_E);
5548 Make_Index (Index, P, Related_Id, Nb_Index);
5550 -- Check error of subtype with predicate for index type
5552 Bad_Predicated_Subtype_Use
5553 ("subtype& has predicate, not allowed as index subtype",
5554 Index, Etype (Index));
5556 -- Move to next index
5559 Nb_Index := Nb_Index + 1;
5562 -- Process subtype indication if one is present
5564 if Present (Component_Typ) then
5565 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5567 Set_Etype (Component_Typ, Element_Type);
5569 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5570 Check_SPARK_05_Restriction
5571 ("subtype mark required", Component_Typ);
5574 -- Ada 2005 (AI-230): Access Definition case
5576 else pragma Assert (Present (Access_Definition (Component_Def)));
5578 -- Indicate that the anonymous access type is created by the
5579 -- array type declaration.
5581 Element_Type := Access_Definition
5583 N => Access_Definition (Component_Def));
5584 Set_Is_Local_Anonymous_Access (Element_Type);
5586 -- Propagate the parent. This field is needed if we have to generate
5587 -- the master_id associated with an anonymous access to task type
5588 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5590 Set_Parent (Element_Type, Parent (T));
5592 -- Ada 2005 (AI-230): In case of components that are anonymous access
5593 -- types the level of accessibility depends on the enclosing type
5596 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5598 -- Ada 2005 (AI-254)
5601 CD : constant Node_Id :=
5602 Access_To_Subprogram_Definition
5603 (Access_Definition (Component_Def));
5605 if Present (CD) and then Protected_Present (CD) then
5607 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5612 -- Constrained array case
5615 T := Create_Itype (E_Void, P, Related_Id, 'T');
5618 if Nkind (Def) = N_Constrained_Array_Definition then
5620 -- Establish Implicit_Base as unconstrained base type
5622 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5624 Set_Etype (Implicit_Base, Implicit_Base);
5625 Set_Scope (Implicit_Base, Current_Scope);
5626 Set_Has_Delayed_Freeze (Implicit_Base);
5627 Set_Default_SSO (Implicit_Base);
5629 -- The constrained array type is a subtype of the unconstrained one
5631 Set_Ekind (T, E_Array_Subtype);
5632 Init_Size_Align (T);
5633 Set_Etype (T, Implicit_Base);
5634 Set_Scope (T, Current_Scope);
5635 Set_Is_Constrained (T);
5637 First (Discrete_Subtype_Definitions (Def)));
5638 Set_Has_Delayed_Freeze (T);
5640 -- Complete setup of implicit base type
5642 Set_Component_Size (Implicit_Base, Uint_0);
5643 Set_Component_Type (Implicit_Base, Element_Type);
5644 Set_Finalize_Storage_Only
5646 Finalize_Storage_Only (Element_Type));
5647 Set_First_Index (Implicit_Base, First_Index (T));
5648 Set_Has_Controlled_Component
5650 Has_Controlled_Component (Element_Type)
5651 or else Is_Controlled_Active (Element_Type));
5652 Set_Packed_Array_Impl_Type
5653 (Implicit_Base, Empty);
5655 Propagate_Concurrent_Flags (Implicit_Base, Element_Type);
5657 -- Inherit the "ghostness" from the constrained array type
5659 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
5660 Set_Is_Ghost_Entity (Implicit_Base);
5663 -- Unconstrained array case
5666 Set_Ekind (T, E_Array_Type);
5667 Init_Size_Align (T);
5669 Set_Scope (T, Current_Scope);
5670 Set_Component_Size (T, Uint_0);
5671 Set_Is_Constrained (T, False);
5672 Set_First_Index (T, First (Subtype_Marks (Def)));
5673 Set_Has_Delayed_Freeze (T, True);
5674 Propagate_Concurrent_Flags (T, Element_Type);
5675 Set_Has_Controlled_Component (T, Has_Controlled_Component
5678 Is_Controlled_Active (Element_Type));
5679 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5681 Set_Default_SSO (T);
5684 -- Common attributes for both cases
5686 Set_Component_Type (Base_Type (T), Element_Type);
5687 Set_Packed_Array_Impl_Type (T, Empty);
5689 if Aliased_Present (Component_Definition (Def)) then
5690 Check_SPARK_05_Restriction
5691 ("aliased is not allowed", Component_Definition (Def));
5692 Set_Has_Aliased_Components (Etype (T));
5695 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5696 -- array type to ensure that objects of this type are initialized.
5698 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5699 Set_Can_Never_Be_Null (T);
5701 if Null_Exclusion_Present (Component_Definition (Def))
5703 -- No need to check itypes because in their case this check was
5704 -- done at their point of creation
5706 and then not Is_Itype (Element_Type)
5709 ("`NOT NULL` not allowed (null already excluded)",
5710 Subtype_Indication (Component_Definition (Def)));
5714 Priv := Private_Component (Element_Type);
5716 if Present (Priv) then
5718 -- Check for circular definitions
5720 if Priv = Any_Type then
5721 Set_Component_Type (Etype (T), Any_Type);
5723 -- There is a gap in the visibility of operations on the composite
5724 -- type only if the component type is defined in a different scope.
5726 elsif Scope (Priv) = Current_Scope then
5729 elsif Is_Limited_Type (Priv) then
5730 Set_Is_Limited_Composite (Etype (T));
5731 Set_Is_Limited_Composite (T);
5733 Set_Is_Private_Composite (Etype (T));
5734 Set_Is_Private_Composite (T);
5738 -- A syntax error in the declaration itself may lead to an empty index
5739 -- list, in which case do a minimal patch.
5741 if No (First_Index (T)) then
5742 Error_Msg_N ("missing index definition in array type declaration", T);
5745 Indexes : constant List_Id :=
5746 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5748 Set_Discrete_Subtype_Definitions (Def, Indexes);
5749 Set_First_Index (T, First (Indexes));
5754 -- Create a concatenation operator for the new type. Internal array
5755 -- types created for packed entities do not need such, they are
5756 -- compatible with the user-defined type.
5758 if Number_Dimensions (T) = 1
5759 and then not Is_Packed_Array_Impl_Type (T)
5761 New_Concatenation_Op (T);
5764 -- In the case of an unconstrained array the parser has already verified
5765 -- that all the indexes are unconstrained but we still need to make sure
5766 -- that the element type is constrained.
5768 if not Is_Definite_Subtype (Element_Type) then
5770 ("unconstrained element type in array declaration",
5771 Subtype_Indication (Component_Def));
5773 elsif Is_Abstract_Type (Element_Type) then
5775 ("the type of a component cannot be abstract",
5776 Subtype_Indication (Component_Def));
5779 -- There may be an invariant declared for the component type, but
5780 -- the construction of the component invariant checking procedure
5781 -- takes place during expansion.
5782 end Array_Type_Declaration;
5784 ------------------------------------------------------
5785 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5786 ------------------------------------------------------
5788 function Replace_Anonymous_Access_To_Protected_Subprogram
5789 (N : Node_Id) return Entity_Id
5791 Loc : constant Source_Ptr := Sloc (N);
5793 Curr_Scope : constant Scope_Stack_Entry :=
5794 Scope_Stack.Table (Scope_Stack.Last);
5796 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5799 -- Access definition in declaration
5802 -- Object definition or formal definition with an access definition
5805 -- Declaration of anonymous access to subprogram type
5808 -- Original specification in access to subprogram
5813 Set_Is_Internal (Anon);
5816 when N_Component_Declaration |
5817 N_Unconstrained_Array_Definition |
5818 N_Constrained_Array_Definition =>
5819 Comp := Component_Definition (N);
5820 Acc := Access_Definition (Comp);
5822 when N_Discriminant_Specification =>
5823 Comp := Discriminant_Type (N);
5826 when N_Parameter_Specification =>
5827 Comp := Parameter_Type (N);
5830 when N_Access_Function_Definition =>
5831 Comp := Result_Definition (N);
5834 when N_Object_Declaration =>
5835 Comp := Object_Definition (N);
5838 when N_Function_Specification =>
5839 Comp := Result_Definition (N);
5843 raise Program_Error;
5846 Spec := Access_To_Subprogram_Definition (Acc);
5849 Make_Full_Type_Declaration (Loc,
5850 Defining_Identifier => Anon,
5851 Type_Definition => Copy_Separate_Tree (Spec));
5853 Mark_Rewrite_Insertion (Decl);
5855 -- In ASIS mode, analyze the profile on the original node, because
5856 -- the separate copy does not provide enough links to recover the
5857 -- original tree. Analysis is limited to type annotations, within
5858 -- a temporary scope that serves as an anonymous subprogram to collect
5859 -- otherwise useless temporaries and itypes.
5863 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5866 if Nkind (Spec) = N_Access_Function_Definition then
5867 Set_Ekind (Typ, E_Function);
5869 Set_Ekind (Typ, E_Procedure);
5872 Set_Parent (Typ, N);
5873 Set_Scope (Typ, Current_Scope);
5876 -- Nothing to do if procedure is parameterless
5878 if Present (Parameter_Specifications (Spec)) then
5879 Process_Formals (Parameter_Specifications (Spec), Spec);
5882 if Nkind (Spec) = N_Access_Function_Definition then
5884 Def : constant Node_Id := Result_Definition (Spec);
5887 -- The result might itself be an anonymous access type, so
5890 if Nkind (Def) = N_Access_Definition then
5891 if Present (Access_To_Subprogram_Definition (Def)) then
5894 Replace_Anonymous_Access_To_Protected_Subprogram
5897 Find_Type (Subtype_Mark (Def));
5910 -- Insert the new declaration in the nearest enclosing scope. If the
5911 -- parent is a body and N is its return type, the declaration belongs
5912 -- in the enclosing scope. Likewise if N is the type of a parameter.
5916 if Nkind (N) = N_Function_Specification
5917 and then Nkind (P) = N_Subprogram_Body
5920 elsif Nkind (N) = N_Parameter_Specification
5921 and then Nkind (P) in N_Subprogram_Specification
5922 and then Nkind (Parent (P)) = N_Subprogram_Body
5924 P := Parent (Parent (P));
5927 while Present (P) and then not Has_Declarations (P) loop
5931 pragma Assert (Present (P));
5933 if Nkind (P) = N_Package_Specification then
5934 Prepend (Decl, Visible_Declarations (P));
5936 Prepend (Decl, Declarations (P));
5939 -- Replace the anonymous type with an occurrence of the new declaration.
5940 -- In all cases the rewritten node does not have the null-exclusion
5941 -- attribute because (if present) it was already inherited by the
5942 -- anonymous entity (Anon). Thus, in case of components we do not
5943 -- inherit this attribute.
5945 if Nkind (N) = N_Parameter_Specification then
5946 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5947 Set_Etype (Defining_Identifier (N), Anon);
5948 Set_Null_Exclusion_Present (N, False);
5950 elsif Nkind (N) = N_Object_Declaration then
5951 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5952 Set_Etype (Defining_Identifier (N), Anon);
5954 elsif Nkind (N) = N_Access_Function_Definition then
5955 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5957 elsif Nkind (N) = N_Function_Specification then
5958 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5959 Set_Etype (Defining_Unit_Name (N), Anon);
5963 Make_Component_Definition (Loc,
5964 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5967 Mark_Rewrite_Insertion (Comp);
5969 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
5970 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
5971 and then not Is_Type (Current_Scope))
5974 -- Declaration can be analyzed in the current scope.
5979 -- Temporarily remove the current scope (record or subprogram) from
5980 -- the stack to add the new declarations to the enclosing scope.
5981 -- The anonymous entity is an Itype with the proper attributes.
5983 Scope_Stack.Decrement_Last;
5985 Set_Is_Itype (Anon);
5986 Set_Associated_Node_For_Itype (Anon, N);
5987 Scope_Stack.Append (Curr_Scope);
5990 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5991 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5993 end Replace_Anonymous_Access_To_Protected_Subprogram;
5995 -------------------------------
5996 -- Build_Derived_Access_Type --
5997 -------------------------------
5999 procedure Build_Derived_Access_Type
6001 Parent_Type : Entity_Id;
6002 Derived_Type : Entity_Id)
6004 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
6006 Desig_Type : Entity_Id;
6008 Discr_Con_Elist : Elist_Id;
6009 Discr_Con_El : Elmt_Id;
6013 -- Set the designated type so it is available in case this is an access
6014 -- to a self-referential type, e.g. a standard list type with a next
6015 -- pointer. Will be reset after subtype is built.
6017 Set_Directly_Designated_Type
6018 (Derived_Type, Designated_Type (Parent_Type));
6020 Subt := Process_Subtype (S, N);
6022 if Nkind (S) /= N_Subtype_Indication
6023 and then Subt /= Base_Type (Subt)
6025 Set_Ekind (Derived_Type, E_Access_Subtype);
6028 if Ekind (Derived_Type) = E_Access_Subtype then
6030 Pbase : constant Entity_Id := Base_Type (Parent_Type);
6031 Ibase : constant Entity_Id :=
6032 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
6033 Svg_Chars : constant Name_Id := Chars (Ibase);
6034 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
6037 Copy_Node (Pbase, Ibase);
6039 -- Restore Itype status after Copy_Node
6041 Set_Is_Itype (Ibase);
6042 Set_Associated_Node_For_Itype (Ibase, N);
6044 Set_Chars (Ibase, Svg_Chars);
6045 Set_Next_Entity (Ibase, Svg_Next_E);
6046 Set_Sloc (Ibase, Sloc (Derived_Type));
6047 Set_Scope (Ibase, Scope (Derived_Type));
6048 Set_Freeze_Node (Ibase, Empty);
6049 Set_Is_Frozen (Ibase, False);
6050 Set_Comes_From_Source (Ibase, False);
6051 Set_Is_First_Subtype (Ibase, False);
6053 Set_Etype (Ibase, Pbase);
6054 Set_Etype (Derived_Type, Ibase);
6058 Set_Directly_Designated_Type
6059 (Derived_Type, Designated_Type (Subt));
6061 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
6062 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
6063 Set_Size_Info (Derived_Type, Parent_Type);
6064 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
6065 Set_Depends_On_Private (Derived_Type,
6066 Has_Private_Component (Derived_Type));
6067 Conditional_Delay (Derived_Type, Subt);
6069 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
6070 -- that it is not redundant.
6072 if Null_Exclusion_Present (Type_Definition (N)) then
6073 Set_Can_Never_Be_Null (Derived_Type);
6075 elsif Can_Never_Be_Null (Parent_Type) then
6076 Set_Can_Never_Be_Null (Derived_Type);
6079 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6080 -- the root type for this information.
6082 -- Apply range checks to discriminants for derived record case
6083 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6085 Desig_Type := Designated_Type (Derived_Type);
6087 if Is_Composite_Type (Desig_Type)
6088 and then (not Is_Array_Type (Desig_Type))
6089 and then Has_Discriminants (Desig_Type)
6090 and then Base_Type (Desig_Type) /= Desig_Type
6092 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6093 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6095 Discr := First_Discriminant (Base_Type (Desig_Type));
6096 while Present (Discr_Con_El) loop
6097 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6098 Next_Elmt (Discr_Con_El);
6099 Next_Discriminant (Discr);
6102 end Build_Derived_Access_Type;
6104 ------------------------------
6105 -- Build_Derived_Array_Type --
6106 ------------------------------
6108 procedure Build_Derived_Array_Type
6110 Parent_Type : Entity_Id;
6111 Derived_Type : Entity_Id)
6113 Loc : constant Source_Ptr := Sloc (N);
6114 Tdef : constant Node_Id := Type_Definition (N);
6115 Indic : constant Node_Id := Subtype_Indication (Tdef);
6116 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6117 Implicit_Base : Entity_Id;
6118 New_Indic : Node_Id;
6120 procedure Make_Implicit_Base;
6121 -- If the parent subtype is constrained, the derived type is a subtype
6122 -- of an implicit base type derived from the parent base.
6124 ------------------------
6125 -- Make_Implicit_Base --
6126 ------------------------
6128 procedure Make_Implicit_Base is
6131 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6133 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6134 Set_Etype (Implicit_Base, Parent_Base);
6136 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6137 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6139 Set_Has_Delayed_Freeze (Implicit_Base, True);
6141 -- Inherit the "ghostness" from the parent base type
6143 if Ghost_Mode > None or else Is_Ghost_Entity (Parent_Base) then
6144 Set_Is_Ghost_Entity (Implicit_Base);
6146 end Make_Implicit_Base;
6148 -- Start of processing for Build_Derived_Array_Type
6151 if not Is_Constrained (Parent_Type) then
6152 if Nkind (Indic) /= N_Subtype_Indication then
6153 Set_Ekind (Derived_Type, E_Array_Type);
6155 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6156 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6158 Set_Has_Delayed_Freeze (Derived_Type, True);
6162 Set_Etype (Derived_Type, Implicit_Base);
6165 Make_Subtype_Declaration (Loc,
6166 Defining_Identifier => Derived_Type,
6167 Subtype_Indication =>
6168 Make_Subtype_Indication (Loc,
6169 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6170 Constraint => Constraint (Indic)));
6172 Rewrite (N, New_Indic);
6177 if Nkind (Indic) /= N_Subtype_Indication then
6180 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6181 Set_Etype (Derived_Type, Implicit_Base);
6182 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6185 Error_Msg_N ("illegal constraint on constrained type", Indic);
6189 -- If parent type is not a derived type itself, and is declared in
6190 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6191 -- the new type's concatenation operator since Derive_Subprograms
6192 -- will not inherit the parent's operator. If the parent type is
6193 -- unconstrained, the operator is of the unconstrained base type.
6195 if Number_Dimensions (Parent_Type) = 1
6196 and then not Is_Limited_Type (Parent_Type)
6197 and then not Is_Derived_Type (Parent_Type)
6198 and then not Is_Package_Or_Generic_Package
6199 (Scope (Base_Type (Parent_Type)))
6201 if not Is_Constrained (Parent_Type)
6202 and then Is_Constrained (Derived_Type)
6204 New_Concatenation_Op (Implicit_Base);
6206 New_Concatenation_Op (Derived_Type);
6209 end Build_Derived_Array_Type;
6211 -----------------------------------
6212 -- Build_Derived_Concurrent_Type --
6213 -----------------------------------
6215 procedure Build_Derived_Concurrent_Type
6217 Parent_Type : Entity_Id;
6218 Derived_Type : Entity_Id)
6220 Loc : constant Source_Ptr := Sloc (N);
6222 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6223 Corr_Decl : Node_Id;
6224 Corr_Decl_Needed : Boolean;
6225 -- If the derived type has fewer discriminants than its parent, the
6226 -- corresponding record is also a derived type, in order to account for
6227 -- the bound discriminants. We create a full type declaration for it in
6230 Constraint_Present : constant Boolean :=
6231 Nkind (Subtype_Indication (Type_Definition (N))) =
6232 N_Subtype_Indication;
6234 D_Constraint : Node_Id;
6235 New_Constraint : Elist_Id;
6236 Old_Disc : Entity_Id;
6237 New_Disc : Entity_Id;
6241 Set_Stored_Constraint (Derived_Type, No_Elist);
6242 Corr_Decl_Needed := False;
6245 if Present (Discriminant_Specifications (N))
6246 and then Constraint_Present
6248 Old_Disc := First_Discriminant (Parent_Type);
6249 New_Disc := First (Discriminant_Specifications (N));
6250 while Present (New_Disc) and then Present (Old_Disc) loop
6251 Next_Discriminant (Old_Disc);
6256 if Present (Old_Disc) and then Expander_Active then
6258 -- The new type has fewer discriminants, so we need to create a new
6259 -- corresponding record, which is derived from the corresponding
6260 -- record of the parent, and has a stored constraint that captures
6261 -- the values of the discriminant constraints. The corresponding
6262 -- record is needed only if expander is active and code generation is
6265 -- The type declaration for the derived corresponding record has the
6266 -- same discriminant part and constraints as the current declaration.
6267 -- Copy the unanalyzed tree to build declaration.
6269 Corr_Decl_Needed := True;
6270 New_N := Copy_Separate_Tree (N);
6273 Make_Full_Type_Declaration (Loc,
6274 Defining_Identifier => Corr_Record,
6275 Discriminant_Specifications =>
6276 Discriminant_Specifications (New_N),
6278 Make_Derived_Type_Definition (Loc,
6279 Subtype_Indication =>
6280 Make_Subtype_Indication (Loc,
6283 (Corresponding_Record_Type (Parent_Type), Loc),
6286 (Subtype_Indication (Type_Definition (New_N))))));
6289 -- Copy Storage_Size and Relative_Deadline variables if task case
6291 if Is_Task_Type (Parent_Type) then
6292 Set_Storage_Size_Variable (Derived_Type,
6293 Storage_Size_Variable (Parent_Type));
6294 Set_Relative_Deadline_Variable (Derived_Type,
6295 Relative_Deadline_Variable (Parent_Type));
6298 if Present (Discriminant_Specifications (N)) then
6299 Push_Scope (Derived_Type);
6300 Check_Or_Process_Discriminants (N, Derived_Type);
6302 if Constraint_Present then
6304 Expand_To_Stored_Constraint
6306 Build_Discriminant_Constraints
6308 Subtype_Indication (Type_Definition (N)), True));
6313 elsif Constraint_Present then
6315 -- Build constrained subtype, copying the constraint, and derive
6316 -- from it to create a derived constrained type.
6319 Loc : constant Source_Ptr := Sloc (N);
6320 Anon : constant Entity_Id :=
6321 Make_Defining_Identifier (Loc,
6322 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6327 Make_Subtype_Declaration (Loc,
6328 Defining_Identifier => Anon,
6329 Subtype_Indication =>
6330 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6331 Insert_Before (N, Decl);
6334 Rewrite (Subtype_Indication (Type_Definition (N)),
6335 New_Occurrence_Of (Anon, Loc));
6336 Set_Analyzed (Derived_Type, False);
6342 -- By default, operations and private data are inherited from parent.
6343 -- However, in the presence of bound discriminants, a new corresponding
6344 -- record will be created, see below.
6346 Set_Has_Discriminants
6347 (Derived_Type, Has_Discriminants (Parent_Type));
6348 Set_Corresponding_Record_Type
6349 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6351 -- Is_Constrained is set according the parent subtype, but is set to
6352 -- False if the derived type is declared with new discriminants.
6356 (Is_Constrained (Parent_Type) or else Constraint_Present)
6357 and then not Present (Discriminant_Specifications (N)));
6359 if Constraint_Present then
6360 if not Has_Discriminants (Parent_Type) then
6361 Error_Msg_N ("untagged parent must have discriminants", N);
6363 elsif Present (Discriminant_Specifications (N)) then
6365 -- Verify that new discriminants are used to constrain old ones
6370 (Constraint (Subtype_Indication (Type_Definition (N)))));
6372 Old_Disc := First_Discriminant (Parent_Type);
6374 while Present (D_Constraint) loop
6375 if Nkind (D_Constraint) /= N_Discriminant_Association then
6377 -- Positional constraint. If it is a reference to a new
6378 -- discriminant, it constrains the corresponding old one.
6380 if Nkind (D_Constraint) = N_Identifier then
6381 New_Disc := First_Discriminant (Derived_Type);
6382 while Present (New_Disc) loop
6383 exit when Chars (New_Disc) = Chars (D_Constraint);
6384 Next_Discriminant (New_Disc);
6387 if Present (New_Disc) then
6388 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6392 Next_Discriminant (Old_Disc);
6394 -- if this is a named constraint, search by name for the old
6395 -- discriminants constrained by the new one.
6397 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6399 -- Find new discriminant with that name
6401 New_Disc := First_Discriminant (Derived_Type);
6402 while Present (New_Disc) loop
6404 Chars (New_Disc) = Chars (Expression (D_Constraint));
6405 Next_Discriminant (New_Disc);
6408 if Present (New_Disc) then
6410 -- Verify that new discriminant renames some discriminant
6411 -- of the parent type, and associate the new discriminant
6412 -- with one or more old ones that it renames.
6418 Selector := First (Selector_Names (D_Constraint));
6419 while Present (Selector) loop
6420 Old_Disc := First_Discriminant (Parent_Type);
6421 while Present (Old_Disc) loop
6422 exit when Chars (Old_Disc) = Chars (Selector);
6423 Next_Discriminant (Old_Disc);
6426 if Present (Old_Disc) then
6427 Set_Corresponding_Discriminant
6428 (New_Disc, Old_Disc);
6437 Next (D_Constraint);
6440 New_Disc := First_Discriminant (Derived_Type);
6441 while Present (New_Disc) loop
6442 if No (Corresponding_Discriminant (New_Disc)) then
6444 ("new discriminant& must constrain old one", N, New_Disc);
6447 Subtypes_Statically_Compatible
6449 Etype (Corresponding_Discriminant (New_Disc)))
6452 ("& not statically compatible with parent discriminant",
6456 Next_Discriminant (New_Disc);
6460 elsif Present (Discriminant_Specifications (N)) then
6462 ("missing discriminant constraint in untagged derivation", N);
6465 -- The entity chain of the derived type includes the new discriminants
6466 -- but shares operations with the parent.
6468 if Present (Discriminant_Specifications (N)) then
6469 Old_Disc := First_Discriminant (Parent_Type);
6470 while Present (Old_Disc) loop
6471 if No (Next_Entity (Old_Disc))
6472 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6475 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6479 Next_Discriminant (Old_Disc);
6483 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6484 if Has_Discriminants (Parent_Type) then
6485 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6486 Set_Discriminant_Constraint (
6487 Derived_Type, Discriminant_Constraint (Parent_Type));
6491 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6493 Set_Has_Completion (Derived_Type);
6495 if Corr_Decl_Needed then
6496 Set_Stored_Constraint (Derived_Type, New_Constraint);
6497 Insert_After (N, Corr_Decl);
6498 Analyze (Corr_Decl);
6499 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6501 end Build_Derived_Concurrent_Type;
6503 ------------------------------------
6504 -- Build_Derived_Enumeration_Type --
6505 ------------------------------------
6507 procedure Build_Derived_Enumeration_Type
6509 Parent_Type : Entity_Id;
6510 Derived_Type : Entity_Id)
6512 Loc : constant Source_Ptr := Sloc (N);
6513 Def : constant Node_Id := Type_Definition (N);
6514 Indic : constant Node_Id := Subtype_Indication (Def);
6515 Implicit_Base : Entity_Id;
6516 Literal : Entity_Id;
6517 New_Lit : Entity_Id;
6518 Literals_List : List_Id;
6519 Type_Decl : Node_Id;
6521 Rang_Expr : Node_Id;
6524 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6525 -- not have explicit literals lists we need to process types derived
6526 -- from them specially. This is handled by Derived_Standard_Character.
6527 -- If the parent type is a generic type, there are no literals either,
6528 -- and we construct the same skeletal representation as for the generic
6531 if Is_Standard_Character_Type (Parent_Type) then
6532 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6534 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6540 if Nkind (Indic) /= N_Subtype_Indication then
6542 Make_Attribute_Reference (Loc,
6543 Attribute_Name => Name_First,
6544 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6545 Set_Etype (Lo, Derived_Type);
6548 Make_Attribute_Reference (Loc,
6549 Attribute_Name => Name_Last,
6550 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6551 Set_Etype (Hi, Derived_Type);
6553 Set_Scalar_Range (Derived_Type,
6559 -- Analyze subtype indication and verify compatibility
6560 -- with parent type.
6562 if Base_Type (Process_Subtype (Indic, N)) /=
6563 Base_Type (Parent_Type)
6566 ("illegal constraint for formal discrete type", N);
6572 -- If a constraint is present, analyze the bounds to catch
6573 -- premature usage of the derived literals.
6575 if Nkind (Indic) = N_Subtype_Indication
6576 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6578 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6579 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6582 -- Introduce an implicit base type for the derived type even if there
6583 -- is no constraint attached to it, since this seems closer to the
6584 -- Ada semantics. Build a full type declaration tree for the derived
6585 -- type using the implicit base type as the defining identifier. The
6586 -- build a subtype declaration tree which applies the constraint (if
6587 -- any) have it replace the derived type declaration.
6589 Literal := First_Literal (Parent_Type);
6590 Literals_List := New_List;
6591 while Present (Literal)
6592 and then Ekind (Literal) = E_Enumeration_Literal
6594 -- Literals of the derived type have the same representation as
6595 -- those of the parent type, but this representation can be
6596 -- overridden by an explicit representation clause. Indicate
6597 -- that there is no explicit representation given yet. These
6598 -- derived literals are implicit operations of the new type,
6599 -- and can be overridden by explicit ones.
6601 if Nkind (Literal) = N_Defining_Character_Literal then
6603 Make_Defining_Character_Literal (Loc, Chars (Literal));
6605 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6608 Set_Ekind (New_Lit, E_Enumeration_Literal);
6609 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6610 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6611 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6612 Set_Alias (New_Lit, Literal);
6613 Set_Is_Known_Valid (New_Lit, True);
6615 Append (New_Lit, Literals_List);
6616 Next_Literal (Literal);
6620 Make_Defining_Identifier (Sloc (Derived_Type),
6621 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6623 -- Indicate the proper nature of the derived type. This must be done
6624 -- before analysis of the literals, to recognize cases when a literal
6625 -- may be hidden by a previous explicit function definition (cf.
6628 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6629 Set_Etype (Derived_Type, Implicit_Base);
6632 Make_Full_Type_Declaration (Loc,
6633 Defining_Identifier => Implicit_Base,
6634 Discriminant_Specifications => No_List,
6636 Make_Enumeration_Type_Definition (Loc, Literals_List));
6638 Mark_Rewrite_Insertion (Type_Decl);
6639 Insert_Before (N, Type_Decl);
6640 Analyze (Type_Decl);
6642 -- The anonymous base now has a full declaration, but this base
6643 -- is not a first subtype.
6645 Set_Is_First_Subtype (Implicit_Base, False);
6647 -- After the implicit base is analyzed its Etype needs to be changed
6648 -- to reflect the fact that it is derived from the parent type which
6649 -- was ignored during analysis. We also set the size at this point.
6651 Set_Etype (Implicit_Base, Parent_Type);
6653 Set_Size_Info (Implicit_Base, Parent_Type);
6654 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6655 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6657 -- Copy other flags from parent type
6659 Set_Has_Non_Standard_Rep
6660 (Implicit_Base, Has_Non_Standard_Rep
6662 Set_Has_Pragma_Ordered
6663 (Implicit_Base, Has_Pragma_Ordered
6665 Set_Has_Delayed_Freeze (Implicit_Base);
6667 -- Process the subtype indication including a validation check on the
6668 -- constraint, if any. If a constraint is given, its bounds must be
6669 -- implicitly converted to the new type.
6671 if Nkind (Indic) = N_Subtype_Indication then
6673 R : constant Node_Id :=
6674 Range_Expression (Constraint (Indic));
6677 if Nkind (R) = N_Range then
6678 Hi := Build_Scalar_Bound
6679 (High_Bound (R), Parent_Type, Implicit_Base);
6680 Lo := Build_Scalar_Bound
6681 (Low_Bound (R), Parent_Type, Implicit_Base);
6684 -- Constraint is a Range attribute. Replace with explicit
6685 -- mention of the bounds of the prefix, which must be a
6688 Analyze (Prefix (R));
6690 Convert_To (Implicit_Base,
6691 Make_Attribute_Reference (Loc,
6692 Attribute_Name => Name_Last,
6694 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6697 Convert_To (Implicit_Base,
6698 Make_Attribute_Reference (Loc,
6699 Attribute_Name => Name_First,
6701 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6708 (Type_High_Bound (Parent_Type),
6709 Parent_Type, Implicit_Base);
6712 (Type_Low_Bound (Parent_Type),
6713 Parent_Type, Implicit_Base);
6721 -- If we constructed a default range for the case where no range
6722 -- was given, then the expressions in the range must not freeze
6723 -- since they do not correspond to expressions in the source.
6725 if Nkind (Indic) /= N_Subtype_Indication then
6726 Set_Must_Not_Freeze (Lo);
6727 Set_Must_Not_Freeze (Hi);
6728 Set_Must_Not_Freeze (Rang_Expr);
6732 Make_Subtype_Declaration (Loc,
6733 Defining_Identifier => Derived_Type,
6734 Subtype_Indication =>
6735 Make_Subtype_Indication (Loc,
6736 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6738 Make_Range_Constraint (Loc,
6739 Range_Expression => Rang_Expr))));
6743 -- Propagate the aspects from the original type declaration to the
6744 -- declaration of the implicit base.
6746 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6748 -- Apply a range check. Since this range expression doesn't have an
6749 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6752 if Nkind (Indic) = N_Subtype_Indication then
6754 (Range_Expression (Constraint (Indic)), Parent_Type,
6755 Source_Typ => Entity (Subtype_Mark (Indic)));
6758 end Build_Derived_Enumeration_Type;
6760 --------------------------------
6761 -- Build_Derived_Numeric_Type --
6762 --------------------------------
6764 procedure Build_Derived_Numeric_Type
6766 Parent_Type : Entity_Id;
6767 Derived_Type : Entity_Id)
6769 Loc : constant Source_Ptr := Sloc (N);
6770 Tdef : constant Node_Id := Type_Definition (N);
6771 Indic : constant Node_Id := Subtype_Indication (Tdef);
6772 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6773 No_Constraint : constant Boolean := Nkind (Indic) /=
6774 N_Subtype_Indication;
6775 Implicit_Base : Entity_Id;
6781 -- Process the subtype indication including a validation check on
6782 -- the constraint if any.
6784 Discard_Node (Process_Subtype (Indic, N));
6786 -- Introduce an implicit base type for the derived type even if there
6787 -- is no constraint attached to it, since this seems closer to the Ada
6791 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6793 Set_Etype (Implicit_Base, Parent_Base);
6794 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6795 Set_Size_Info (Implicit_Base, Parent_Base);
6796 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6797 Set_Parent (Implicit_Base, Parent (Derived_Type));
6798 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6800 -- Set RM Size for discrete type or decimal fixed-point type
6801 -- Ordinary fixed-point is excluded, why???
6803 if Is_Discrete_Type (Parent_Base)
6804 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6806 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6809 Set_Has_Delayed_Freeze (Implicit_Base);
6811 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6812 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6814 Set_Scalar_Range (Implicit_Base,
6819 if Has_Infinities (Parent_Base) then
6820 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6823 -- The Derived_Type, which is the entity of the declaration, is a
6824 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6825 -- absence of an explicit constraint.
6827 Set_Etype (Derived_Type, Implicit_Base);
6829 -- If we did not have a constraint, then the Ekind is set from the
6830 -- parent type (otherwise Process_Subtype has set the bounds)
6832 if No_Constraint then
6833 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6836 -- If we did not have a range constraint, then set the range from the
6837 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6839 if No_Constraint or else not Has_Range_Constraint (Indic) then
6840 Set_Scalar_Range (Derived_Type,
6842 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6843 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6844 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6846 if Has_Infinities (Parent_Type) then
6847 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6850 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6853 Set_Is_Descendant_Of_Address (Derived_Type,
6854 Is_Descendant_Of_Address (Parent_Type));
6855 Set_Is_Descendant_Of_Address (Implicit_Base,
6856 Is_Descendant_Of_Address (Parent_Type));
6858 -- Set remaining type-specific fields, depending on numeric type
6860 if Is_Modular_Integer_Type (Parent_Type) then
6861 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6863 Set_Non_Binary_Modulus
6864 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6867 (Implicit_Base, Is_Known_Valid (Parent_Base));
6869 elsif Is_Floating_Point_Type (Parent_Type) then
6871 -- Digits of base type is always copied from the digits value of
6872 -- the parent base type, but the digits of the derived type will
6873 -- already have been set if there was a constraint present.
6875 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6876 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6878 if No_Constraint then
6879 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6882 elsif Is_Fixed_Point_Type (Parent_Type) then
6884 -- Small of base type and derived type are always copied from the
6885 -- parent base type, since smalls never change. The delta of the
6886 -- base type is also copied from the parent base type. However the
6887 -- delta of the derived type will have been set already if a
6888 -- constraint was present.
6890 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6891 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6892 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6894 if No_Constraint then
6895 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6898 -- The scale and machine radix in the decimal case are always
6899 -- copied from the parent base type.
6901 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6902 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6903 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6905 Set_Machine_Radix_10
6906 (Derived_Type, Machine_Radix_10 (Parent_Base));
6907 Set_Machine_Radix_10
6908 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6910 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6912 if No_Constraint then
6913 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6916 -- the analysis of the subtype_indication sets the
6917 -- digits value of the derived type.
6924 if Is_Integer_Type (Parent_Type) then
6925 Set_Has_Shift_Operator
6926 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6929 -- The type of the bounds is that of the parent type, and they
6930 -- must be converted to the derived type.
6932 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6934 -- The implicit_base should be frozen when the derived type is frozen,
6935 -- but note that it is used in the conversions of the bounds. For fixed
6936 -- types we delay the determination of the bounds until the proper
6937 -- freezing point. For other numeric types this is rejected by GCC, for
6938 -- reasons that are currently unclear (???), so we choose to freeze the
6939 -- implicit base now. In the case of integers and floating point types
6940 -- this is harmless because subsequent representation clauses cannot
6941 -- affect anything, but it is still baffling that we cannot use the
6942 -- same mechanism for all derived numeric types.
6944 -- There is a further complication: actually some representation
6945 -- clauses can affect the implicit base type. For example, attribute
6946 -- definition clauses for stream-oriented attributes need to set the
6947 -- corresponding TSS entries on the base type, and this normally
6948 -- cannot be done after the base type is frozen, so the circuitry in
6949 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6950 -- and not use Set_TSS in this case.
6952 -- There are also consequences for the case of delayed representation
6953 -- aspects for some cases. For example, a Size aspect is delayed and
6954 -- should not be evaluated to the freeze point. This early freezing
6955 -- means that the size attribute evaluation happens too early???
6957 if Is_Fixed_Point_Type (Parent_Type) then
6958 Conditional_Delay (Implicit_Base, Parent_Type);
6960 Freeze_Before (N, Implicit_Base);
6962 end Build_Derived_Numeric_Type;
6964 --------------------------------
6965 -- Build_Derived_Private_Type --
6966 --------------------------------
6968 procedure Build_Derived_Private_Type
6970 Parent_Type : Entity_Id;
6971 Derived_Type : Entity_Id;
6972 Is_Completion : Boolean;
6973 Derive_Subps : Boolean := True)
6975 Loc : constant Source_Ptr := Sloc (N);
6976 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6977 Par_Scope : constant Entity_Id := Scope (Par_Base);
6978 Full_N : constant Node_Id := New_Copy_Tree (N);
6979 Full_Der : Entity_Id := New_Copy (Derived_Type);
6982 procedure Build_Full_Derivation;
6983 -- Build full derivation, i.e. derive from the full view
6985 procedure Copy_And_Build;
6986 -- Copy derived type declaration, replace parent with its full view,
6987 -- and build derivation
6989 ---------------------------
6990 -- Build_Full_Derivation --
6991 ---------------------------
6993 procedure Build_Full_Derivation is
6995 -- If parent scope is not open, install the declarations
6997 if not In_Open_Scopes (Par_Scope) then
6998 Install_Private_Declarations (Par_Scope);
6999 Install_Visible_Declarations (Par_Scope);
7001 Uninstall_Declarations (Par_Scope);
7003 -- If parent scope is open and in another unit, and parent has a
7004 -- completion, then the derivation is taking place in the visible
7005 -- part of a child unit. In that case retrieve the full view of
7006 -- the parent momentarily.
7008 elsif not In_Same_Source_Unit (N, Parent_Type) then
7009 Full_P := Full_View (Parent_Type);
7010 Exchange_Declarations (Parent_Type);
7012 Exchange_Declarations (Full_P);
7014 -- Otherwise it is a local derivation
7019 end Build_Full_Derivation;
7021 --------------------
7022 -- Copy_And_Build --
7023 --------------------
7025 procedure Copy_And_Build is
7026 Full_Parent : Entity_Id := Parent_Type;
7029 -- If the parent is itself derived from another private type,
7030 -- installing the private declarations has not affected its
7031 -- privacy status, so use its own full view explicitly.
7033 if Is_Private_Type (Full_Parent)
7034 and then Present (Full_View (Full_Parent))
7036 Full_Parent := Full_View (Full_Parent);
7039 -- And its underlying full view if necessary
7041 if Is_Private_Type (Full_Parent)
7042 and then Present (Underlying_Full_View (Full_Parent))
7044 Full_Parent := Underlying_Full_View (Full_Parent);
7047 -- For record, access and most enumeration types, derivation from
7048 -- the full view requires a fully-fledged declaration. In the other
7049 -- cases, just use an itype.
7051 if Ekind (Full_Parent) in Record_Kind
7052 or else Ekind (Full_Parent) in Access_Kind
7054 (Ekind (Full_Parent) in Enumeration_Kind
7055 and then not Is_Standard_Character_Type (Full_Parent)
7056 and then not Is_Generic_Type (Root_Type (Full_Parent)))
7058 -- Copy and adjust declaration to provide a completion for what
7059 -- is originally a private declaration. Indicate that full view
7060 -- is internally generated.
7062 Set_Comes_From_Source (Full_N, False);
7063 Set_Comes_From_Source (Full_Der, False);
7064 Set_Parent (Full_Der, Full_N);
7065 Set_Defining_Identifier (Full_N, Full_Der);
7067 -- If there are no constraints, adjust the subtype mark
7069 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
7070 N_Subtype_Indication
7072 Set_Subtype_Indication
7073 (Type_Definition (Full_N),
7074 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
7077 Insert_After (N, Full_N);
7079 -- Build full view of derived type from full view of parent which
7080 -- is now installed. Subprograms have been derived on the partial
7081 -- view, the completion does not derive them anew.
7083 if Ekind (Full_Parent) in Record_Kind then
7085 -- If parent type is tagged, the completion inherits the proper
7086 -- primitive operations.
7088 if Is_Tagged_Type (Parent_Type) then
7089 Build_Derived_Record_Type
7090 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7092 Build_Derived_Record_Type
7093 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7098 (Full_N, Full_Parent, Full_Der,
7099 Is_Completion => False, Derive_Subps => False);
7102 -- The full declaration has been introduced into the tree and
7103 -- processed in the step above. It should not be analyzed again
7104 -- (when encountered later in the current list of declarations)
7105 -- to prevent spurious name conflicts. The full entity remains
7108 Set_Analyzed (Full_N);
7112 Make_Defining_Identifier (Sloc (Derived_Type),
7113 Chars => Chars (Derived_Type));
7114 Set_Is_Itype (Full_Der);
7115 Set_Associated_Node_For_Itype (Full_Der, N);
7116 Set_Parent (Full_Der, N);
7118 (N, Full_Parent, Full_Der,
7119 Is_Completion => False, Derive_Subps => False);
7122 Set_Has_Private_Declaration (Full_Der);
7123 Set_Has_Private_Declaration (Derived_Type);
7125 Set_Scope (Full_Der, Scope (Derived_Type));
7126 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7127 Set_Has_Size_Clause (Full_Der, False);
7128 Set_Has_Alignment_Clause (Full_Der, False);
7129 Set_Has_Delayed_Freeze (Full_Der);
7130 Set_Is_Frozen (Full_Der, False);
7131 Set_Freeze_Node (Full_Der, Empty);
7132 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7133 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7135 -- The convention on the base type may be set in the private part
7136 -- and not propagated to the subtype until later, so we obtain the
7137 -- convention from the base type of the parent.
7139 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7142 -- Start of processing for Build_Derived_Private_Type
7145 if Is_Tagged_Type (Parent_Type) then
7146 Full_P := Full_View (Parent_Type);
7148 -- A type extension of a type with unknown discriminants is an
7149 -- indefinite type that the back-end cannot handle directly.
7150 -- We treat it as a private type, and build a completion that is
7151 -- derived from the full view of the parent, and hopefully has
7152 -- known discriminants.
7154 -- If the full view of the parent type has an underlying record view,
7155 -- use it to generate the underlying record view of this derived type
7156 -- (required for chains of derivations with unknown discriminants).
7158 -- Minor optimization: we avoid the generation of useless underlying
7159 -- record view entities if the private type declaration has unknown
7160 -- discriminants but its corresponding full view has no
7163 if Has_Unknown_Discriminants (Parent_Type)
7164 and then Present (Full_P)
7165 and then (Has_Discriminants (Full_P)
7166 or else Present (Underlying_Record_View (Full_P)))
7167 and then not In_Open_Scopes (Par_Scope)
7168 and then Expander_Active
7171 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7172 New_Ext : constant Node_Id :=
7174 (Record_Extension_Part (Type_Definition (N)));
7178 Build_Derived_Record_Type
7179 (N, Parent_Type, Derived_Type, Derive_Subps);
7181 -- Build anonymous completion, as a derivation from the full
7182 -- view of the parent. This is not a completion in the usual
7183 -- sense, because the current type is not private.
7186 Make_Full_Type_Declaration (Loc,
7187 Defining_Identifier => Full_Der,
7189 Make_Derived_Type_Definition (Loc,
7190 Subtype_Indication =>
7192 (Subtype_Indication (Type_Definition (N))),
7193 Record_Extension_Part => New_Ext));
7195 -- If the parent type has an underlying record view, use it
7196 -- here to build the new underlying record view.
7198 if Present (Underlying_Record_View (Full_P)) then
7200 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7202 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7203 Underlying_Record_View (Full_P));
7206 Install_Private_Declarations (Par_Scope);
7207 Install_Visible_Declarations (Par_Scope);
7208 Insert_Before (N, Decl);
7210 -- Mark entity as an underlying record view before analysis,
7211 -- to avoid generating the list of its primitive operations
7212 -- (which is not really required for this entity) and thus
7213 -- prevent spurious errors associated with missing overriding
7214 -- of abstract primitives (overridden only for Derived_Type).
7216 Set_Ekind (Full_Der, E_Record_Type);
7217 Set_Is_Underlying_Record_View (Full_Der);
7218 Set_Default_SSO (Full_Der);
7222 pragma Assert (Has_Discriminants (Full_Der)
7223 and then not Has_Unknown_Discriminants (Full_Der));
7225 Uninstall_Declarations (Par_Scope);
7227 -- Freeze the underlying record view, to prevent generation of
7228 -- useless dispatching information, which is simply shared with
7229 -- the real derived type.
7231 Set_Is_Frozen (Full_Der);
7233 -- If the derived type has access discriminants, create
7234 -- references to their anonymous types now, to prevent
7235 -- back-end problems when their first use is in generated
7236 -- bodies of primitives.
7242 E := First_Entity (Full_Der);
7244 while Present (E) loop
7245 if Ekind (E) = E_Discriminant
7246 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7248 Build_Itype_Reference (Etype (E), Decl);
7255 -- Set up links between real entity and underlying record view
7257 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7258 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7261 -- If discriminants are known, build derived record
7264 Build_Derived_Record_Type
7265 (N, Parent_Type, Derived_Type, Derive_Subps);
7270 elsif Has_Discriminants (Parent_Type) then
7272 -- Build partial view of derived type from partial view of parent.
7273 -- This must be done before building the full derivation because the
7274 -- second derivation will modify the discriminants of the first and
7275 -- the discriminants are chained with the rest of the components in
7276 -- the full derivation.
7278 Build_Derived_Record_Type
7279 (N, Parent_Type, Derived_Type, Derive_Subps);
7281 -- Build the full derivation if this is not the anonymous derived
7282 -- base type created by Build_Derived_Record_Type in the constrained
7283 -- case (see point 5. of its head comment) since we build it for the
7284 -- derived subtype. And skip it for protected types altogether, as
7285 -- gigi does not use these types directly.
7287 if Present (Full_View (Parent_Type))
7288 and then not Is_Itype (Derived_Type)
7289 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7292 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7294 Last_Discr : Entity_Id;
7297 -- If this is not a completion, construct the implicit full
7298 -- view by deriving from the full view of the parent type.
7299 -- But if this is a completion, the derived private type
7300 -- being built is a full view and the full derivation can
7301 -- only be its underlying full view.
7303 Build_Full_Derivation;
7305 if not Is_Completion then
7306 Set_Full_View (Derived_Type, Full_Der);
7308 Set_Underlying_Full_View (Derived_Type, Full_Der);
7311 if not Is_Base_Type (Derived_Type) then
7312 Set_Full_View (Der_Base, Base_Type (Full_Der));
7315 -- Copy the discriminant list from full view to the partial
7316 -- view (base type and its subtype). Gigi requires that the
7317 -- partial and full views have the same discriminants.
7319 -- Note that since the partial view points to discriminants
7320 -- in the full view, their scope will be that of the full
7321 -- view. This might cause some front end problems and need
7324 Discr := First_Discriminant (Base_Type (Full_Der));
7325 Set_First_Entity (Der_Base, Discr);
7328 Last_Discr := Discr;
7329 Next_Discriminant (Discr);
7330 exit when No (Discr);
7333 Set_Last_Entity (Der_Base, Last_Discr);
7334 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7335 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7337 Set_Stored_Constraint
7338 (Full_Der, Stored_Constraint (Derived_Type));
7342 elsif Present (Full_View (Parent_Type))
7343 and then Has_Discriminants (Full_View (Parent_Type))
7345 if Has_Unknown_Discriminants (Parent_Type)
7346 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7347 N_Subtype_Indication
7350 ("cannot constrain type with unknown discriminants",
7351 Subtype_Indication (Type_Definition (N)));
7355 -- If this is not a completion, construct the implicit full view by
7356 -- deriving from the full view of the parent type. But if this is a
7357 -- completion, the derived private type being built is a full view
7358 -- and the full derivation can only be its underlying full view.
7360 Build_Full_Derivation;
7362 if not Is_Completion then
7363 Set_Full_View (Derived_Type, Full_Der);
7365 Set_Underlying_Full_View (Derived_Type, Full_Der);
7368 -- In any case, the primitive operations are inherited from the
7369 -- parent type, not from the internal full view.
7371 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7373 if Derive_Subps then
7374 Derive_Subprograms (Parent_Type, Derived_Type);
7377 Set_Stored_Constraint (Derived_Type, No_Elist);
7379 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7382 -- Untagged type, No discriminants on either view
7384 if Nkind (Subtype_Indication (Type_Definition (N))) =
7385 N_Subtype_Indication
7388 ("illegal constraint on type without discriminants", N);
7391 if Present (Discriminant_Specifications (N))
7392 and then Present (Full_View (Parent_Type))
7393 and then not Is_Tagged_Type (Full_View (Parent_Type))
7395 Error_Msg_N ("cannot add discriminants to untagged type", N);
7398 Set_Stored_Constraint (Derived_Type, No_Elist);
7399 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7400 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7401 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7403 Set_Has_Controlled_Component
7404 (Derived_Type, Has_Controlled_Component
7407 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7409 if not Is_Controlled_Active (Parent_Type) then
7410 Set_Finalize_Storage_Only
7411 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7414 -- If this is not a completion, construct the implicit full view by
7415 -- deriving from the full view of the parent type.
7417 -- ??? If the parent is untagged private and its completion is
7418 -- tagged, this mechanism will not work because we cannot derive from
7419 -- the tagged full view unless we have an extension.
7421 if Present (Full_View (Parent_Type))
7422 and then not Is_Tagged_Type (Full_View (Parent_Type))
7423 and then not Is_Completion
7425 Build_Full_Derivation;
7426 Set_Full_View (Derived_Type, Full_Der);
7430 Set_Has_Unknown_Discriminants (Derived_Type,
7431 Has_Unknown_Discriminants (Parent_Type));
7433 if Is_Private_Type (Derived_Type) then
7434 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7437 -- If the parent base type is in scope, add the derived type to its
7438 -- list of private dependents, because its full view may become
7439 -- visible subsequently (in a nested private part, a body, or in a
7440 -- further child unit).
7442 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7443 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7445 -- Check for unusual case where a type completed by a private
7446 -- derivation occurs within a package nested in a child unit, and
7447 -- the parent is declared in an ancestor.
7449 if Is_Child_Unit (Scope (Current_Scope))
7450 and then Is_Completion
7451 and then In_Private_Part (Current_Scope)
7452 and then Scope (Parent_Type) /= Current_Scope
7454 -- Note that if the parent has a completion in the private part,
7455 -- (which is itself a derivation from some other private type)
7456 -- it is that completion that is visible, there is no full view
7457 -- available, and no special processing is needed.
7459 and then Present (Full_View (Parent_Type))
7461 -- In this case, the full view of the parent type will become
7462 -- visible in the body of the enclosing child, and only then will
7463 -- the current type be possibly non-private. Build an underlying
7464 -- full view that will be installed when the enclosing child body
7467 if Present (Underlying_Full_View (Derived_Type)) then
7468 Full_Der := Underlying_Full_View (Derived_Type);
7470 Build_Full_Derivation;
7471 Set_Underlying_Full_View (Derived_Type, Full_Der);
7474 -- The full view will be used to swap entities on entry/exit to
7475 -- the body, and must appear in the entity list for the package.
7477 Append_Entity (Full_Der, Scope (Derived_Type));
7480 end Build_Derived_Private_Type;
7482 -------------------------------
7483 -- Build_Derived_Record_Type --
7484 -------------------------------
7488 -- Ideally we would like to use the same model of type derivation for
7489 -- tagged and untagged record types. Unfortunately this is not quite
7490 -- possible because the semantics of representation clauses is different
7491 -- for tagged and untagged records under inheritance. Consider the
7494 -- type R (...) is [tagged] record ... end record;
7495 -- type T (...) is new R (...) [with ...];
7497 -- The representation clauses for T can specify a completely different
7498 -- record layout from R's. Hence the same component can be placed in two
7499 -- very different positions in objects of type T and R. If R and T are
7500 -- tagged types, representation clauses for T can only specify the layout
7501 -- of non inherited components, thus components that are common in R and T
7502 -- have the same position in objects of type R and T.
7504 -- This has two implications. The first is that the entire tree for R's
7505 -- declaration needs to be copied for T in the untagged case, so that T
7506 -- can be viewed as a record type of its own with its own representation
7507 -- clauses. The second implication is the way we handle discriminants.
7508 -- Specifically, in the untagged case we need a way to communicate to Gigi
7509 -- what are the real discriminants in the record, while for the semantics
7510 -- we need to consider those introduced by the user to rename the
7511 -- discriminants in the parent type. This is handled by introducing the
7512 -- notion of stored discriminants. See below for more.
7514 -- Fortunately the way regular components are inherited can be handled in
7515 -- the same way in tagged and untagged types.
7517 -- To complicate things a bit more the private view of a private extension
7518 -- cannot be handled in the same way as the full view (for one thing the
7519 -- semantic rules are somewhat different). We will explain what differs
7522 -- 2. DISCRIMINANTS UNDER INHERITANCE
7524 -- The semantic rules governing the discriminants of derived types are
7527 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7528 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7530 -- If parent type has discriminants, then the discriminants that are
7531 -- declared in the derived type are [3.4 (11)]:
7533 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7536 -- o Otherwise, each discriminant of the parent type (implicitly declared
7537 -- in the same order with the same specifications). In this case, the
7538 -- discriminants are said to be "inherited", or if unknown in the parent
7539 -- are also unknown in the derived type.
7541 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7543 -- o The parent subtype must be constrained;
7545 -- o If the parent type is not a tagged type, then each discriminant of
7546 -- the derived type must be used in the constraint defining a parent
7547 -- subtype. [Implementation note: This ensures that the new discriminant
7548 -- can share storage with an existing discriminant.]
7550 -- For the derived type each discriminant of the parent type is either
7551 -- inherited, constrained to equal some new discriminant of the derived
7552 -- type, or constrained to the value of an expression.
7554 -- When inherited or constrained to equal some new discriminant, the
7555 -- parent discriminant and the discriminant of the derived type are said
7558 -- If a discriminant of the parent type is constrained to a specific value
7559 -- in the derived type definition, then the discriminant is said to be
7560 -- "specified" by that derived type definition.
7562 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7564 -- We have spoken about stored discriminants in point 1 (introduction)
7565 -- above. There are two sort of stored discriminants: implicit and
7566 -- explicit. As long as the derived type inherits the same discriminants as
7567 -- the root record type, stored discriminants are the same as regular
7568 -- discriminants, and are said to be implicit. However, if any discriminant
7569 -- in the root type was renamed in the derived type, then the derived
7570 -- type will contain explicit stored discriminants. Explicit stored
7571 -- discriminants are discriminants in addition to the semantically visible
7572 -- discriminants defined for the derived type. Stored discriminants are
7573 -- used by Gigi to figure out what are the physical discriminants in
7574 -- objects of the derived type (see precise definition in einfo.ads).
7575 -- As an example, consider the following:
7577 -- type R (D1, D2, D3 : Int) is record ... end record;
7578 -- type T1 is new R;
7579 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7580 -- type T3 is new T2;
7581 -- type T4 (Y : Int) is new T3 (Y, 99);
7583 -- The following table summarizes the discriminants and stored
7584 -- discriminants in R and T1 through T4.
7586 -- Type Discrim Stored Discrim Comment
7587 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7588 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7589 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7590 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7591 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7593 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7594 -- find the corresponding discriminant in the parent type, while
7595 -- Original_Record_Component (abbreviated ORC below), the actual physical
7596 -- component that is renamed. Finally the field Is_Completely_Hidden
7597 -- (abbreviated ICH below) is set for all explicit stored discriminants
7598 -- (see einfo.ads for more info). For the above example this gives:
7600 -- Discrim CD ORC ICH
7601 -- ^^^^^^^ ^^ ^^^ ^^^
7602 -- D1 in R empty itself no
7603 -- D2 in R empty itself no
7604 -- D3 in R empty itself no
7606 -- D1 in T1 D1 in R itself no
7607 -- D2 in T1 D2 in R itself no
7608 -- D3 in T1 D3 in R itself no
7610 -- X1 in T2 D3 in T1 D3 in T2 no
7611 -- X2 in T2 D1 in T1 D1 in T2 no
7612 -- D1 in T2 empty itself yes
7613 -- D2 in T2 empty itself yes
7614 -- D3 in T2 empty itself yes
7616 -- X1 in T3 X1 in T2 D3 in T3 no
7617 -- X2 in T3 X2 in T2 D1 in T3 no
7618 -- D1 in T3 empty itself yes
7619 -- D2 in T3 empty itself yes
7620 -- D3 in T3 empty itself yes
7622 -- Y in T4 X1 in T3 D3 in T3 no
7623 -- D1 in T3 empty itself yes
7624 -- D2 in T3 empty itself yes
7625 -- D3 in T3 empty itself yes
7627 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7629 -- Type derivation for tagged types is fairly straightforward. If no
7630 -- discriminants are specified by the derived type, these are inherited
7631 -- from the parent. No explicit stored discriminants are ever necessary.
7632 -- The only manipulation that is done to the tree is that of adding a
7633 -- _parent field with parent type and constrained to the same constraint
7634 -- specified for the parent in the derived type definition. For instance:
7636 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7637 -- type T1 is new R with null record;
7638 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7640 -- are changed into:
7642 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7643 -- _parent : R (D1, D2, D3);
7646 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7647 -- _parent : T1 (X2, 88, X1);
7650 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7651 -- ORC and ICH fields are:
7653 -- Discrim CD ORC ICH
7654 -- ^^^^^^^ ^^ ^^^ ^^^
7655 -- D1 in R empty itself no
7656 -- D2 in R empty itself no
7657 -- D3 in R empty itself no
7659 -- D1 in T1 D1 in R D1 in R no
7660 -- D2 in T1 D2 in R D2 in R no
7661 -- D3 in T1 D3 in R D3 in R no
7663 -- X1 in T2 D3 in T1 D3 in R no
7664 -- X2 in T2 D1 in T1 D1 in R no
7666 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7668 -- Regardless of whether we dealing with a tagged or untagged type
7669 -- we will transform all derived type declarations of the form
7671 -- type T is new R (...) [with ...];
7673 -- subtype S is R (...);
7674 -- type T is new S [with ...];
7676 -- type BT is new R [with ...];
7677 -- subtype T is BT (...);
7679 -- That is, the base derived type is constrained only if it has no
7680 -- discriminants. The reason for doing this is that GNAT's semantic model
7681 -- assumes that a base type with discriminants is unconstrained.
7683 -- Note that, strictly speaking, the above transformation is not always
7684 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7686 -- procedure B34011A is
7687 -- type REC (D : integer := 0) is record
7692 -- type T6 is new Rec;
7693 -- function F return T6;
7698 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7701 -- The definition of Q6.U is illegal. However transforming Q6.U into
7703 -- type BaseU is new T6;
7704 -- subtype U is BaseU (Q6.F.I)
7706 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7707 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7708 -- the transformation described above.
7710 -- There is another instance where the above transformation is incorrect.
7714 -- type Base (D : Integer) is tagged null record;
7715 -- procedure P (X : Base);
7717 -- type Der is new Base (2) with null record;
7718 -- procedure P (X : Der);
7721 -- Then the above transformation turns this into
7723 -- type Der_Base is new Base with null record;
7724 -- -- procedure P (X : Base) is implicitly inherited here
7725 -- -- as procedure P (X : Der_Base).
7727 -- subtype Der is Der_Base (2);
7728 -- procedure P (X : Der);
7729 -- -- The overriding of P (X : Der_Base) is illegal since we
7730 -- -- have a parameter conformance problem.
7732 -- To get around this problem, after having semantically processed Der_Base
7733 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7734 -- Discriminant_Constraint from Der so that when parameter conformance is
7735 -- checked when P is overridden, no semantic errors are flagged.
7737 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7739 -- Regardless of whether we are dealing with a tagged or untagged type
7740 -- we will transform all derived type declarations of the form
7742 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7743 -- type T is new R [with ...];
7745 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7747 -- The reason for such transformation is that it allows us to implement a
7748 -- very clean form of component inheritance as explained below.
7750 -- Note that this transformation is not achieved by direct tree rewriting
7751 -- and manipulation, but rather by redoing the semantic actions that the
7752 -- above transformation will entail. This is done directly in routine
7753 -- Inherit_Components.
7755 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7757 -- In both tagged and untagged derived types, regular non discriminant
7758 -- components are inherited in the derived type from the parent type. In
7759 -- the absence of discriminants component, inheritance is straightforward
7760 -- as components can simply be copied from the parent.
7762 -- If the parent has discriminants, inheriting components constrained with
7763 -- these discriminants requires caution. Consider the following example:
7765 -- type R (D1, D2 : Positive) is [tagged] record
7766 -- S : String (D1 .. D2);
7769 -- type T1 is new R [with null record];
7770 -- type T2 (X : positive) is new R (1, X) [with null record];
7772 -- As explained in 6. above, T1 is rewritten as
7773 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7774 -- which makes the treatment for T1 and T2 identical.
7776 -- What we want when inheriting S, is that references to D1 and D2 in R are
7777 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7778 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7779 -- with either discriminant references in the derived type or expressions.
7780 -- This replacement is achieved as follows: before inheriting R's
7781 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7782 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7783 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7784 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7785 -- by String (1 .. X).
7787 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7789 -- We explain here the rules governing private type extensions relevant to
7790 -- type derivation. These rules are explained on the following example:
7792 -- type D [(...)] is new A [(...)] with private; <-- partial view
7793 -- type D [(...)] is new P [(...)] with null record; <-- full view
7795 -- Type A is called the ancestor subtype of the private extension.
7796 -- Type P is the parent type of the full view of the private extension. It
7797 -- must be A or a type derived from A.
7799 -- The rules concerning the discriminants of private type extensions are
7802 -- o If a private extension inherits known discriminants from the ancestor
7803 -- subtype, then the full view must also inherit its discriminants from
7804 -- the ancestor subtype and the parent subtype of the full view must be
7805 -- constrained if and only if the ancestor subtype is constrained.
7807 -- o If a partial view has unknown discriminants, then the full view may
7808 -- define a definite or an indefinite subtype, with or without
7811 -- o If a partial view has neither known nor unknown discriminants, then
7812 -- the full view must define a definite subtype.
7814 -- o If the ancestor subtype of a private extension has constrained
7815 -- discriminants, then the parent subtype of the full view must impose a
7816 -- statically matching constraint on those discriminants.
7818 -- This means that only the following forms of private extensions are
7821 -- type D is new A with private; <-- partial view
7822 -- type D is new P with null record; <-- full view
7824 -- If A has no discriminants than P has no discriminants, otherwise P must
7825 -- inherit A's discriminants.
7827 -- type D is new A (...) with private; <-- partial view
7828 -- type D is new P (:::) with null record; <-- full view
7830 -- P must inherit A's discriminants and (...) and (:::) must statically
7833 -- subtype A is R (...);
7834 -- type D is new A with private; <-- partial view
7835 -- type D is new P with null record; <-- full view
7837 -- P must have inherited R's discriminants and must be derived from A or
7838 -- any of its subtypes.
7840 -- type D (..) is new A with private; <-- partial view
7841 -- type D (..) is new P [(:::)] with null record; <-- full view
7843 -- No specific constraints on P's discriminants or constraint (:::).
7844 -- Note that A can be unconstrained, but the parent subtype P must either
7845 -- be constrained or (:::) must be present.
7847 -- type D (..) is new A [(...)] with private; <-- partial view
7848 -- type D (..) is new P [(:::)] with null record; <-- full view
7850 -- P's constraints on A's discriminants must statically match those
7851 -- imposed by (...).
7853 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7855 -- The full view of a private extension is handled exactly as described
7856 -- above. The model chose for the private view of a private extension is
7857 -- the same for what concerns discriminants (i.e. they receive the same
7858 -- treatment as in the tagged case). However, the private view of the
7859 -- private extension always inherits the components of the parent base,
7860 -- without replacing any discriminant reference. Strictly speaking this is
7861 -- incorrect. However, Gigi never uses this view to generate code so this
7862 -- is a purely semantic issue. In theory, a set of transformations similar
7863 -- to those given in 5. and 6. above could be applied to private views of
7864 -- private extensions to have the same model of component inheritance as
7865 -- for non private extensions. However, this is not done because it would
7866 -- further complicate private type processing. Semantically speaking, this
7867 -- leaves us in an uncomfortable situation. As an example consider:
7870 -- type R (D : integer) is tagged record
7871 -- S : String (1 .. D);
7873 -- procedure P (X : R);
7874 -- type T is new R (1) with private;
7876 -- type T is new R (1) with null record;
7879 -- This is transformed into:
7882 -- type R (D : integer) is tagged record
7883 -- S : String (1 .. D);
7885 -- procedure P (X : R);
7886 -- type T is new R (1) with private;
7888 -- type BaseT is new R with null record;
7889 -- subtype T is BaseT (1);
7892 -- (strictly speaking the above is incorrect Ada)
7894 -- From the semantic standpoint the private view of private extension T
7895 -- should be flagged as constrained since one can clearly have
7899 -- in a unit withing Pack. However, when deriving subprograms for the
7900 -- private view of private extension T, T must be seen as unconstrained
7901 -- since T has discriminants (this is a constraint of the current
7902 -- subprogram derivation model). Thus, when processing the private view of
7903 -- a private extension such as T, we first mark T as unconstrained, we
7904 -- process it, we perform program derivation and just before returning from
7905 -- Build_Derived_Record_Type we mark T as constrained.
7907 -- ??? Are there are other uncomfortable cases that we will have to
7910 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7912 -- Types that are derived from a visible record type and have a private
7913 -- extension present other peculiarities. They behave mostly like private
7914 -- types, but if they have primitive operations defined, these will not
7915 -- have the proper signatures for further inheritance, because other
7916 -- primitive operations will use the implicit base that we define for
7917 -- private derivations below. This affect subprogram inheritance (see
7918 -- Derive_Subprograms for details). We also derive the implicit base from
7919 -- the base type of the full view, so that the implicit base is a record
7920 -- type and not another private type, This avoids infinite loops.
7922 procedure Build_Derived_Record_Type
7924 Parent_Type : Entity_Id;
7925 Derived_Type : Entity_Id;
7926 Derive_Subps : Boolean := True)
7928 Discriminant_Specs : constant Boolean :=
7929 Present (Discriminant_Specifications (N));
7930 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7931 Loc : constant Source_Ptr := Sloc (N);
7932 Private_Extension : constant Boolean :=
7933 Nkind (N) = N_Private_Extension_Declaration;
7934 Assoc_List : Elist_Id;
7935 Constraint_Present : Boolean;
7937 Discrim : Entity_Id;
7939 Inherit_Discrims : Boolean := False;
7940 Last_Discrim : Entity_Id;
7941 New_Base : Entity_Id;
7943 New_Discrs : Elist_Id;
7944 New_Indic : Node_Id;
7945 Parent_Base : Entity_Id;
7946 Save_Etype : Entity_Id;
7947 Save_Discr_Constr : Elist_Id;
7948 Save_Next_Entity : Entity_Id;
7951 Discs : Elist_Id := New_Elmt_List;
7952 -- An empty Discs list means that there were no constraints in the
7953 -- subtype indication or that there was an error processing it.
7956 if Ekind (Parent_Type) = E_Record_Type_With_Private
7957 and then Present (Full_View (Parent_Type))
7958 and then Has_Discriminants (Parent_Type)
7960 Parent_Base := Base_Type (Full_View (Parent_Type));
7962 Parent_Base := Base_Type (Parent_Type);
7965 -- AI05-0115 : if this is a derivation from a private type in some
7966 -- other scope that may lead to invisible components for the derived
7967 -- type, mark it accordingly.
7969 if Is_Private_Type (Parent_Type) then
7970 if Scope (Parent_Type) = Scope (Derived_Type) then
7973 elsif In_Open_Scopes (Scope (Parent_Type))
7974 and then In_Private_Part (Scope (Parent_Type))
7979 Set_Has_Private_Ancestor (Derived_Type);
7983 Set_Has_Private_Ancestor
7984 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7987 -- Before we start the previously documented transformations, here is
7988 -- little fix for size and alignment of tagged types. Normally when we
7989 -- derive type D from type P, we copy the size and alignment of P as the
7990 -- default for D, and in the absence of explicit representation clauses
7991 -- for D, the size and alignment are indeed the same as the parent.
7993 -- But this is wrong for tagged types, since fields may be added, and
7994 -- the default size may need to be larger, and the default alignment may
7995 -- need to be larger.
7997 -- We therefore reset the size and alignment fields in the tagged case.
7998 -- Note that the size and alignment will in any case be at least as
7999 -- large as the parent type (since the derived type has a copy of the
8000 -- parent type in the _parent field)
8002 -- The type is also marked as being tagged here, which is needed when
8003 -- processing components with a self-referential anonymous access type
8004 -- in the call to Check_Anonymous_Access_Components below. Note that
8005 -- this flag is also set later on for completeness.
8008 Set_Is_Tagged_Type (Derived_Type);
8009 Init_Size_Align (Derived_Type);
8012 -- STEP 0a: figure out what kind of derived type declaration we have
8014 if Private_Extension then
8016 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
8017 Set_Default_SSO (Derived_Type);
8020 Type_Def := Type_Definition (N);
8022 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8023 -- Parent_Base can be a private type or private extension. However,
8024 -- for tagged types with an extension the newly added fields are
8025 -- visible and hence the Derived_Type is always an E_Record_Type.
8026 -- (except that the parent may have its own private fields).
8027 -- For untagged types we preserve the Ekind of the Parent_Base.
8029 if Present (Record_Extension_Part (Type_Def)) then
8030 Set_Ekind (Derived_Type, E_Record_Type);
8031 Set_Default_SSO (Derived_Type);
8033 -- Create internal access types for components with anonymous
8036 if Ada_Version >= Ada_2005 then
8037 Check_Anonymous_Access_Components
8038 (N, Derived_Type, Derived_Type,
8039 Component_List (Record_Extension_Part (Type_Def)));
8043 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8047 -- Indic can either be an N_Identifier if the subtype indication
8048 -- contains no constraint or an N_Subtype_Indication if the subtype
8049 -- indication has a constraint.
8051 Indic := Subtype_Indication (Type_Def);
8052 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
8054 -- Check that the type has visible discriminants. The type may be
8055 -- a private type with unknown discriminants whose full view has
8056 -- discriminants which are invisible.
8058 if Constraint_Present then
8059 if not Has_Discriminants (Parent_Base)
8061 (Has_Unknown_Discriminants (Parent_Base)
8062 and then Is_Private_Type (Parent_Base))
8065 ("invalid constraint: type has no discriminant",
8066 Constraint (Indic));
8068 Constraint_Present := False;
8069 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8071 elsif Is_Constrained (Parent_Type) then
8073 ("invalid constraint: parent type is already constrained",
8074 Constraint (Indic));
8076 Constraint_Present := False;
8077 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8081 -- STEP 0b: If needed, apply transformation given in point 5. above
8083 if not Private_Extension
8084 and then Has_Discriminants (Parent_Type)
8085 and then not Discriminant_Specs
8086 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8088 -- First, we must analyze the constraint (see comment in point 5.)
8089 -- The constraint may come from the subtype indication of the full
8092 if Constraint_Present then
8093 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8095 -- If there is no explicit constraint, there might be one that is
8096 -- inherited from a constrained parent type. In that case verify that
8097 -- it conforms to the constraint in the partial view. In perverse
8098 -- cases the parent subtypes of the partial and full view can have
8099 -- different constraints.
8101 elsif Present (Stored_Constraint (Parent_Type)) then
8102 New_Discrs := Stored_Constraint (Parent_Type);
8105 New_Discrs := No_Elist;
8108 if Has_Discriminants (Derived_Type)
8109 and then Has_Private_Declaration (Derived_Type)
8110 and then Present (Discriminant_Constraint (Derived_Type))
8111 and then Present (New_Discrs)
8113 -- Verify that constraints of the full view statically match
8114 -- those given in the partial view.
8120 C1 := First_Elmt (New_Discrs);
8121 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8122 while Present (C1) and then Present (C2) loop
8123 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8125 (Is_OK_Static_Expression (Node (C1))
8126 and then Is_OK_Static_Expression (Node (C2))
8128 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8133 if Constraint_Present then
8135 ("constraint not conformant to previous declaration",
8139 ("constraint of full view is incompatible "
8140 & "with partial view", N);
8150 -- Insert and analyze the declaration for the unconstrained base type
8152 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8155 Make_Full_Type_Declaration (Loc,
8156 Defining_Identifier => New_Base,
8158 Make_Derived_Type_Definition (Loc,
8159 Abstract_Present => Abstract_Present (Type_Def),
8160 Limited_Present => Limited_Present (Type_Def),
8161 Subtype_Indication =>
8162 New_Occurrence_Of (Parent_Base, Loc),
8163 Record_Extension_Part =>
8164 Relocate_Node (Record_Extension_Part (Type_Def)),
8165 Interface_List => Interface_List (Type_Def)));
8167 Set_Parent (New_Decl, Parent (N));
8168 Mark_Rewrite_Insertion (New_Decl);
8169 Insert_Before (N, New_Decl);
8171 -- In the extension case, make sure ancestor is frozen appropriately
8172 -- (see also non-discriminated case below).
8174 if Present (Record_Extension_Part (Type_Def))
8175 or else Is_Interface (Parent_Base)
8177 Freeze_Before (New_Decl, Parent_Type);
8180 -- Note that this call passes False for the Derive_Subps parameter
8181 -- because subprogram derivation is deferred until after creating
8182 -- the subtype (see below).
8185 (New_Decl, Parent_Base, New_Base,
8186 Is_Completion => False, Derive_Subps => False);
8188 -- ??? This needs re-examination to determine whether the
8189 -- above call can simply be replaced by a call to Analyze.
8191 Set_Analyzed (New_Decl);
8193 -- Insert and analyze the declaration for the constrained subtype
8195 if Constraint_Present then
8197 Make_Subtype_Indication (Loc,
8198 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8199 Constraint => Relocate_Node (Constraint (Indic)));
8203 Constr_List : constant List_Id := New_List;
8208 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8209 while Present (C) loop
8212 -- It is safe here to call New_Copy_Tree since we called
8213 -- Force_Evaluation on each constraint previously
8214 -- in Build_Discriminant_Constraints.
8216 Append (New_Copy_Tree (Expr), To => Constr_List);
8222 Make_Subtype_Indication (Loc,
8223 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8225 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8230 Make_Subtype_Declaration (Loc,
8231 Defining_Identifier => Derived_Type,
8232 Subtype_Indication => New_Indic));
8236 -- Derivation of subprograms must be delayed until the full subtype
8237 -- has been established, to ensure proper overriding of subprograms
8238 -- inherited by full types. If the derivations occurred as part of
8239 -- the call to Build_Derived_Type above, then the check for type
8240 -- conformance would fail because earlier primitive subprograms
8241 -- could still refer to the full type prior the change to the new
8242 -- subtype and hence would not match the new base type created here.
8243 -- Subprograms are not derived, however, when Derive_Subps is False
8244 -- (since otherwise there could be redundant derivations).
8246 if Derive_Subps then
8247 Derive_Subprograms (Parent_Type, Derived_Type);
8250 -- For tagged types the Discriminant_Constraint of the new base itype
8251 -- is inherited from the first subtype so that no subtype conformance
8252 -- problem arise when the first subtype overrides primitive
8253 -- operations inherited by the implicit base type.
8256 Set_Discriminant_Constraint
8257 (New_Base, Discriminant_Constraint (Derived_Type));
8263 -- If we get here Derived_Type will have no discriminants or it will be
8264 -- a discriminated unconstrained base type.
8266 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8270 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8271 -- The declaration of a specific descendant of an interface type
8272 -- freezes the interface type (RM 13.14).
8274 if not Private_Extension or else Is_Interface (Parent_Base) then
8275 Freeze_Before (N, Parent_Type);
8278 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8279 -- cannot be declared at a deeper level than its parent type is
8280 -- removed. The check on derivation within a generic body is also
8281 -- relaxed, but there's a restriction that a derived tagged type
8282 -- cannot be declared in a generic body if it's derived directly
8283 -- or indirectly from a formal type of that generic.
8285 if Ada_Version >= Ada_2005 then
8286 if Present (Enclosing_Generic_Body (Derived_Type)) then
8288 Ancestor_Type : Entity_Id;
8291 -- Check to see if any ancestor of the derived type is a
8294 Ancestor_Type := Parent_Type;
8295 while not Is_Generic_Type (Ancestor_Type)
8296 and then Etype (Ancestor_Type) /= Ancestor_Type
8298 Ancestor_Type := Etype (Ancestor_Type);
8301 -- If the derived type does have a formal type as an
8302 -- ancestor, then it's an error if the derived type is
8303 -- declared within the body of the generic unit that
8304 -- declares the formal type in its generic formal part. It's
8305 -- sufficient to check whether the ancestor type is declared
8306 -- inside the same generic body as the derived type (such as
8307 -- within a nested generic spec), in which case the
8308 -- derivation is legal. If the formal type is declared
8309 -- outside of that generic body, then it's guaranteed that
8310 -- the derived type is declared within the generic body of
8311 -- the generic unit declaring the formal type.
8313 if Is_Generic_Type (Ancestor_Type)
8314 and then Enclosing_Generic_Body (Ancestor_Type) /=
8315 Enclosing_Generic_Body (Derived_Type)
8318 ("parent type of& must not be descendant of formal type"
8319 & " of an enclosing generic body",
8320 Indic, Derived_Type);
8325 elsif Type_Access_Level (Derived_Type) /=
8326 Type_Access_Level (Parent_Type)
8327 and then not Is_Generic_Type (Derived_Type)
8329 if Is_Controlled (Parent_Type) then
8331 ("controlled type must be declared at the library level",
8335 ("type extension at deeper accessibility level than parent",
8341 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8344 and then GB /= Enclosing_Generic_Body (Parent_Base)
8347 ("parent type of& must not be outside generic body"
8349 Indic, Derived_Type);
8355 -- Ada 2005 (AI-251)
8357 if Ada_Version >= Ada_2005 and then Is_Tagged then
8359 -- "The declaration of a specific descendant of an interface type
8360 -- freezes the interface type" (RM 13.14).
8365 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8366 Iface := First (Interface_List (Type_Def));
8367 while Present (Iface) loop
8368 Freeze_Before (N, Etype (Iface));
8375 -- STEP 1b : preliminary cleanup of the full view of private types
8377 -- If the type is already marked as having discriminants, then it's the
8378 -- completion of a private type or private extension and we need to
8379 -- retain the discriminants from the partial view if the current
8380 -- declaration has Discriminant_Specifications so that we can verify
8381 -- conformance. However, we must remove any existing components that
8382 -- were inherited from the parent (and attached in Copy_And_Swap)
8383 -- because the full type inherits all appropriate components anyway, and
8384 -- we do not want the partial view's components interfering.
8386 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8387 Discrim := First_Discriminant (Derived_Type);
8389 Last_Discrim := Discrim;
8390 Next_Discriminant (Discrim);
8391 exit when No (Discrim);
8394 Set_Last_Entity (Derived_Type, Last_Discrim);
8396 -- In all other cases wipe out the list of inherited components (even
8397 -- inherited discriminants), it will be properly rebuilt here.
8400 Set_First_Entity (Derived_Type, Empty);
8401 Set_Last_Entity (Derived_Type, Empty);
8404 -- STEP 1c: Initialize some flags for the Derived_Type
8406 -- The following flags must be initialized here so that
8407 -- Process_Discriminants can check that discriminants of tagged types do
8408 -- not have a default initial value and that access discriminants are
8409 -- only specified for limited records. For completeness, these flags are
8410 -- also initialized along with all the other flags below.
8412 -- AI-419: Limitedness is not inherited from an interface parent, so to
8413 -- be limited in that case the type must be explicitly declared as
8414 -- limited. However, task and protected interfaces are always limited.
8416 if Limited_Present (Type_Def) then
8417 Set_Is_Limited_Record (Derived_Type);
8419 elsif Is_Limited_Record (Parent_Type)
8420 or else (Present (Full_View (Parent_Type))
8421 and then Is_Limited_Record (Full_View (Parent_Type)))
8423 if not Is_Interface (Parent_Type)
8424 or else Is_Synchronized_Interface (Parent_Type)
8425 or else Is_Protected_Interface (Parent_Type)
8426 or else Is_Task_Interface (Parent_Type)
8428 Set_Is_Limited_Record (Derived_Type);
8432 -- STEP 2a: process discriminants of derived type if any
8434 Push_Scope (Derived_Type);
8436 if Discriminant_Specs then
8437 Set_Has_Unknown_Discriminants (Derived_Type, False);
8439 -- The following call initializes fields Has_Discriminants and
8440 -- Discriminant_Constraint, unless we are processing the completion
8441 -- of a private type declaration.
8443 Check_Or_Process_Discriminants (N, Derived_Type);
8445 -- For untagged types, the constraint on the Parent_Type must be
8446 -- present and is used to rename the discriminants.
8448 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8449 Error_Msg_N ("untagged parent must have discriminants", Indic);
8451 elsif not Is_Tagged and then not Constraint_Present then
8453 ("discriminant constraint needed for derived untagged records",
8456 -- Otherwise the parent subtype must be constrained unless we have a
8457 -- private extension.
8459 elsif not Constraint_Present
8460 and then not Private_Extension
8461 and then not Is_Constrained (Parent_Type)
8464 ("unconstrained type not allowed in this context", Indic);
8466 elsif Constraint_Present then
8467 -- The following call sets the field Corresponding_Discriminant
8468 -- for the discriminants in the Derived_Type.
8470 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8472 -- For untagged types all new discriminants must rename
8473 -- discriminants in the parent. For private extensions new
8474 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8476 Discrim := First_Discriminant (Derived_Type);
8477 while Present (Discrim) loop
8479 and then No (Corresponding_Discriminant (Discrim))
8482 ("new discriminants must constrain old ones", Discrim);
8484 elsif Private_Extension
8485 and then Present (Corresponding_Discriminant (Discrim))
8488 ("only static constraints allowed for parent"
8489 & " discriminants in the partial view", Indic);
8493 -- If a new discriminant is used in the constraint, then its
8494 -- subtype must be statically compatible with the parent
8495 -- discriminant's subtype (3.7(15)).
8497 -- However, if the record contains an array constrained by
8498 -- the discriminant but with some different bound, the compiler
8499 -- attemps to create a smaller range for the discriminant type.
8500 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8501 -- the discriminant type is a scalar type, the check must use
8502 -- the original discriminant type in the parent declaration.
8505 Corr_Disc : constant Entity_Id :=
8506 Corresponding_Discriminant (Discrim);
8507 Disc_Type : constant Entity_Id := Etype (Discrim);
8508 Corr_Type : Entity_Id;
8511 if Present (Corr_Disc) then
8512 if Is_Scalar_Type (Disc_Type) then
8514 Entity (Discriminant_Type (Parent (Corr_Disc)));
8516 Corr_Type := Etype (Corr_Disc);
8520 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8523 ("subtype must be compatible "
8524 & "with parent discriminant",
8530 Next_Discriminant (Discrim);
8533 -- Check whether the constraints of the full view statically
8534 -- match those imposed by the parent subtype [7.3(13)].
8536 if Present (Stored_Constraint (Derived_Type)) then
8541 C1 := First_Elmt (Discs);
8542 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8543 while Present (C1) and then Present (C2) loop
8545 Fully_Conformant_Expressions (Node (C1), Node (C2))
8548 ("not conformant with previous declaration",
8559 -- STEP 2b: No new discriminants, inherit discriminants if any
8562 if Private_Extension then
8563 Set_Has_Unknown_Discriminants
8565 Has_Unknown_Discriminants (Parent_Type)
8566 or else Unknown_Discriminants_Present (N));
8568 -- The partial view of the parent may have unknown discriminants,
8569 -- but if the full view has discriminants and the parent type is
8570 -- in scope they must be inherited.
8572 elsif Has_Unknown_Discriminants (Parent_Type)
8574 (not Has_Discriminants (Parent_Type)
8575 or else not In_Open_Scopes (Scope (Parent_Type)))
8577 Set_Has_Unknown_Discriminants (Derived_Type);
8580 if not Has_Unknown_Discriminants (Derived_Type)
8581 and then not Has_Unknown_Discriminants (Parent_Base)
8582 and then Has_Discriminants (Parent_Type)
8584 Inherit_Discrims := True;
8585 Set_Has_Discriminants
8586 (Derived_Type, True);
8587 Set_Discriminant_Constraint
8588 (Derived_Type, Discriminant_Constraint (Parent_Base));
8591 -- The following test is true for private types (remember
8592 -- transformation 5. is not applied to those) and in an error
8595 if Constraint_Present then
8596 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8599 -- For now mark a new derived type as constrained only if it has no
8600 -- discriminants. At the end of Build_Derived_Record_Type we properly
8601 -- set this flag in the case of private extensions. See comments in
8602 -- point 9. just before body of Build_Derived_Record_Type.
8606 not (Inherit_Discrims
8607 or else Has_Unknown_Discriminants (Derived_Type)));
8610 -- STEP 3: initialize fields of derived type
8612 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8613 Set_Stored_Constraint (Derived_Type, No_Elist);
8615 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8616 -- but cannot be interfaces
8618 if not Private_Extension
8619 and then Ekind (Derived_Type) /= E_Private_Type
8620 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8622 if Interface_Present (Type_Def) then
8623 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8626 Set_Interfaces (Derived_Type, No_Elist);
8629 -- Fields inherited from the Parent_Type
8631 Set_Has_Specified_Layout
8632 (Derived_Type, Has_Specified_Layout (Parent_Type));
8633 Set_Is_Limited_Composite
8634 (Derived_Type, Is_Limited_Composite (Parent_Type));
8635 Set_Is_Private_Composite
8636 (Derived_Type, Is_Private_Composite (Parent_Type));
8638 if Is_Tagged_Type (Parent_Type) then
8639 Set_No_Tagged_Streams_Pragma
8640 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8643 -- Fields inherited from the Parent_Base
8645 Set_Has_Controlled_Component
8646 (Derived_Type, Has_Controlled_Component (Parent_Base));
8647 Set_Has_Non_Standard_Rep
8648 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8649 Set_Has_Primitive_Operations
8650 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8652 -- Fields inherited from the Parent_Base in the non-private case
8654 if Ekind (Derived_Type) = E_Record_Type then
8655 Set_Has_Complex_Representation
8656 (Derived_Type, Has_Complex_Representation (Parent_Base));
8659 -- Fields inherited from the Parent_Base for record types
8661 if Is_Record_Type (Derived_Type) then
8663 Parent_Full : Entity_Id;
8666 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8667 -- Parent_Base can be a private type or private extension. Go
8668 -- to the full view here to get the E_Record_Type specific flags.
8670 if Present (Full_View (Parent_Base)) then
8671 Parent_Full := Full_View (Parent_Base);
8673 Parent_Full := Parent_Base;
8676 Set_OK_To_Reorder_Components
8677 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8681 -- Set fields for private derived types
8683 if Is_Private_Type (Derived_Type) then
8684 Set_Depends_On_Private (Derived_Type, True);
8685 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8687 -- Inherit fields from non private record types. If this is the
8688 -- completion of a derivation from a private type, the parent itself
8689 -- is private, and the attributes come from its full view, which must
8693 if Is_Private_Type (Parent_Base)
8694 and then not Is_Record_Type (Parent_Base)
8696 Set_Component_Alignment
8697 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8699 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8701 Set_Component_Alignment
8702 (Derived_Type, Component_Alignment (Parent_Base));
8704 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8708 -- Set fields for tagged types
8711 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8713 -- All tagged types defined in Ada.Finalization are controlled
8715 if Chars (Scope (Derived_Type)) = Name_Finalization
8716 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8717 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8719 Set_Is_Controlled (Derived_Type);
8721 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8724 -- Minor optimization: there is no need to generate the class-wide
8725 -- entity associated with an underlying record view.
8727 if not Is_Underlying_Record_View (Derived_Type) then
8728 Make_Class_Wide_Type (Derived_Type);
8731 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8733 if Has_Discriminants (Derived_Type)
8734 and then Constraint_Present
8736 Set_Stored_Constraint
8737 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8740 if Ada_Version >= Ada_2005 then
8742 Ifaces_List : Elist_Id;
8745 -- Checks rules 3.9.4 (13/2 and 14/2)
8747 if Comes_From_Source (Derived_Type)
8748 and then not Is_Private_Type (Derived_Type)
8749 and then Is_Interface (Parent_Type)
8750 and then not Is_Interface (Derived_Type)
8752 if Is_Task_Interface (Parent_Type) then
8754 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8757 elsif Is_Protected_Interface (Parent_Type) then
8759 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8764 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8766 Check_Interfaces (N, Type_Def);
8768 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8769 -- not already in the parents.
8773 Ifaces_List => Ifaces_List,
8774 Exclude_Parents => True);
8776 Set_Interfaces (Derived_Type, Ifaces_List);
8778 -- If the derived type is the anonymous type created for
8779 -- a declaration whose parent has a constraint, propagate
8780 -- the interface list to the source type. This must be done
8781 -- prior to the completion of the analysis of the source type
8782 -- because the components in the extension may contain current
8783 -- instances whose legality depends on some ancestor.
8785 if Is_Itype (Derived_Type) then
8787 Def : constant Node_Id :=
8788 Associated_Node_For_Itype (Derived_Type);
8791 and then Nkind (Def) = N_Full_Type_Declaration
8794 (Defining_Identifier (Def), Ifaces_List);
8799 -- A derived type inherits any class-wide invariants coming
8800 -- from a parent type or an interface. Note that the invariant
8801 -- procedure of the parent type should not be inherited because
8802 -- the derived type may define invariants of its own.
8804 if Ada_Version >= Ada_2012
8805 and then not Is_Interface (Derived_Type)
8807 if Has_Inherited_Invariants (Parent_Type)
8808 or else Has_Inheritable_Invariants (Parent_Type)
8810 Set_Has_Inherited_Invariants (Derived_Type);
8812 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8815 Iface_Elmt : Elmt_Id;
8818 Iface_Elmt := First_Elmt (Ifaces_List);
8819 while Present (Iface_Elmt) loop
8820 Iface := Node (Iface_Elmt);
8822 if Has_Inheritable_Invariants (Iface) then
8823 Set_Has_Inherited_Invariants (Derived_Type);
8827 Next_Elmt (Iface_Elmt);
8833 -- A type extension is automatically Ghost when one of its
8834 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8835 -- also inherited when the parent type is Ghost, but this is
8836 -- done in Build_Derived_Type as the mechanism also handles
8837 -- untagged derivations.
8839 if Implements_Ghost_Interface (Derived_Type) then
8840 Set_Is_Ghost_Entity (Derived_Type);
8846 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8847 Set_Has_Non_Standard_Rep
8848 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8851 -- STEP 4: Inherit components from the parent base and constrain them.
8852 -- Apply the second transformation described in point 6. above.
8854 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8855 or else not Has_Discriminants (Parent_Type)
8856 or else not Is_Constrained (Parent_Type)
8860 Constrs := Discriminant_Constraint (Parent_Type);
8865 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8867 -- STEP 5a: Copy the parent record declaration for untagged types
8869 if not Is_Tagged then
8871 -- Discriminant_Constraint (Derived_Type) has been properly
8872 -- constructed. Save it and temporarily set it to Empty because we
8873 -- do not want the call to New_Copy_Tree below to mess this list.
8875 if Has_Discriminants (Derived_Type) then
8876 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8877 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8879 Save_Discr_Constr := No_Elist;
8882 -- Save the Etype field of Derived_Type. It is correctly set now,
8883 -- but the call to New_Copy tree may remap it to point to itself,
8884 -- which is not what we want. Ditto for the Next_Entity field.
8886 Save_Etype := Etype (Derived_Type);
8887 Save_Next_Entity := Next_Entity (Derived_Type);
8889 -- Assoc_List maps all stored discriminants in the Parent_Base to
8890 -- stored discriminants in the Derived_Type. It is fundamental that
8891 -- no types or itypes with discriminants other than the stored
8892 -- discriminants appear in the entities declared inside
8893 -- Derived_Type, since the back end cannot deal with it.
8897 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8899 -- Restore the fields saved prior to the New_Copy_Tree call
8900 -- and compute the stored constraint.
8902 Set_Etype (Derived_Type, Save_Etype);
8903 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8905 if Has_Discriminants (Derived_Type) then
8906 Set_Discriminant_Constraint
8907 (Derived_Type, Save_Discr_Constr);
8908 Set_Stored_Constraint
8909 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8910 Replace_Components (Derived_Type, New_Decl);
8911 Set_Has_Implicit_Dereference
8912 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8915 -- Insert the new derived type declaration
8917 Rewrite (N, New_Decl);
8919 -- STEP 5b: Complete the processing for record extensions in generics
8921 -- There is no completion for record extensions declared in the
8922 -- parameter part of a generic, so we need to complete processing for
8923 -- these generic record extensions here. The Record_Type_Definition call
8924 -- will change the Ekind of the components from E_Void to E_Component.
8926 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8927 Record_Type_Definition (Empty, Derived_Type);
8929 -- STEP 5c: Process the record extension for non private tagged types
8931 elsif not Private_Extension then
8932 Expand_Record_Extension (Derived_Type, Type_Def);
8934 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8935 -- derived type to propagate some semantic information. This led
8936 -- to other ASIS failures and has been removed.
8938 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8939 -- implemented interfaces if we are in expansion mode
8942 and then Has_Interfaces (Derived_Type)
8944 Add_Interface_Tag_Components (N, Derived_Type);
8947 -- Analyze the record extension
8949 Record_Type_Definition
8950 (Record_Extension_Part (Type_Def), Derived_Type);
8955 -- Nothing else to do if there is an error in the derivation.
8956 -- An unusual case: the full view may be derived from a type in an
8957 -- instance, when the partial view was used illegally as an actual
8958 -- in that instance, leading to a circular definition.
8960 if Etype (Derived_Type) = Any_Type
8961 or else Etype (Parent_Type) = Derived_Type
8966 -- Set delayed freeze and then derive subprograms, we need to do
8967 -- this in this order so that derived subprograms inherit the
8968 -- derived freeze if necessary.
8970 Set_Has_Delayed_Freeze (Derived_Type);
8972 if Derive_Subps then
8973 Derive_Subprograms (Parent_Type, Derived_Type);
8976 -- If we have a private extension which defines a constrained derived
8977 -- type mark as constrained here after we have derived subprograms. See
8978 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8980 if Private_Extension and then Inherit_Discrims then
8981 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8982 Set_Is_Constrained (Derived_Type, True);
8983 Set_Discriminant_Constraint (Derived_Type, Discs);
8985 elsif Is_Constrained (Parent_Type) then
8987 (Derived_Type, True);
8988 Set_Discriminant_Constraint
8989 (Derived_Type, Discriminant_Constraint (Parent_Type));
8993 -- Update the class-wide type, which shares the now-completed entity
8994 -- list with its specific type. In case of underlying record views,
8995 -- we do not generate the corresponding class wide entity.
8998 and then not Is_Underlying_Record_View (Derived_Type)
9001 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
9003 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
9006 Check_Function_Writable_Actuals (N);
9007 end Build_Derived_Record_Type;
9009 ------------------------
9010 -- Build_Derived_Type --
9011 ------------------------
9013 procedure Build_Derived_Type
9015 Parent_Type : Entity_Id;
9016 Derived_Type : Entity_Id;
9017 Is_Completion : Boolean;
9018 Derive_Subps : Boolean := True)
9020 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
9023 -- Set common attributes
9025 Set_Scope (Derived_Type, Current_Scope);
9027 Set_Etype (Derived_Type, Parent_Base);
9028 Set_Ekind (Derived_Type, Ekind (Parent_Base));
9029 Propagate_Concurrent_Flags (Derived_Type, Parent_Base);
9031 Set_Size_Info (Derived_Type, Parent_Type);
9032 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
9033 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
9034 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
9036 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
9037 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
9039 if Is_Tagged_Type (Derived_Type) then
9040 Set_No_Tagged_Streams_Pragma
9041 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9044 -- If the parent has primitive routines, set the derived type link
9046 if Has_Primitive_Operations (Parent_Type) then
9047 Set_Derived_Type_Link (Parent_Base, Derived_Type);
9050 -- If the parent type is a private subtype, the convention on the base
9051 -- type may be set in the private part, and not propagated to the
9052 -- subtype until later, so we obtain the convention from the base type.
9054 Set_Convention (Derived_Type, Convention (Parent_Base));
9056 -- Set SSO default for record or array type
9058 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
9059 and then Is_Base_Type (Derived_Type)
9061 Set_Default_SSO (Derived_Type);
9064 -- Propagate invariant information. The new type has invariants if
9065 -- they are inherited from the parent type, and these invariants can
9066 -- be further inherited, so both flags are set.
9068 -- We similarly inherit predicates
9070 if Has_Predicates (Parent_Type) then
9071 Set_Has_Predicates (Derived_Type);
9074 -- The derived type inherits the representation clauses of the parent
9076 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
9078 -- Propagate the attributes related to pragma Default_Initial_Condition
9079 -- from the parent type to the private extension. A derived type always
9080 -- inherits the default initial condition flag from the parent type. If
9081 -- the derived type carries its own Default_Initial_Condition pragma,
9082 -- the flag is later reset in Analyze_Pragma. Note that both flags are
9083 -- mutually exclusive.
9085 Propagate_Default_Init_Cond_Attributes
9086 (From_Typ => Parent_Type,
9087 To_Typ => Derived_Type,
9088 Parent_To_Derivation => True);
9090 -- If the parent type has delayed rep aspects, then mark the derived
9091 -- type as possibly inheriting a delayed rep aspect.
9093 if Has_Delayed_Rep_Aspects (Parent_Type) then
9094 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9097 -- Propagate the attributes related to pragma Ghost from the parent type
9098 -- to the derived type or type extension (SPARK RM 6.9(9)).
9100 if Is_Ghost_Entity (Parent_Type) then
9101 Set_Is_Ghost_Entity (Derived_Type);
9104 -- Type dependent processing
9106 case Ekind (Parent_Type) is
9107 when Numeric_Kind =>
9108 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9111 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9115 | Class_Wide_Kind =>
9116 Build_Derived_Record_Type
9117 (N, Parent_Type, Derived_Type, Derive_Subps);
9120 when Enumeration_Kind =>
9121 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9124 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9126 when Incomplete_Or_Private_Kind =>
9127 Build_Derived_Private_Type
9128 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9130 -- For discriminated types, the derivation includes deriving
9131 -- primitive operations. For others it is done below.
9133 if Is_Tagged_Type (Parent_Type)
9134 or else Has_Discriminants (Parent_Type)
9135 or else (Present (Full_View (Parent_Type))
9136 and then Has_Discriminants (Full_View (Parent_Type)))
9141 when Concurrent_Kind =>
9142 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9145 raise Program_Error;
9148 -- Nothing more to do if some error occurred
9150 if Etype (Derived_Type) = Any_Type then
9154 -- Set delayed freeze and then derive subprograms, we need to do this
9155 -- in this order so that derived subprograms inherit the derived freeze
9158 Set_Has_Delayed_Freeze (Derived_Type);
9160 if Derive_Subps then
9161 Derive_Subprograms (Parent_Type, Derived_Type);
9164 Set_Has_Primitive_Operations
9165 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9166 end Build_Derived_Type;
9168 -----------------------
9169 -- Build_Discriminal --
9170 -----------------------
9172 procedure Build_Discriminal (Discrim : Entity_Id) is
9173 D_Minal : Entity_Id;
9174 CR_Disc : Entity_Id;
9177 -- A discriminal has the same name as the discriminant
9179 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9181 Set_Ekind (D_Minal, E_In_Parameter);
9182 Set_Mechanism (D_Minal, Default_Mechanism);
9183 Set_Etype (D_Minal, Etype (Discrim));
9184 Set_Scope (D_Minal, Current_Scope);
9186 Set_Discriminal (Discrim, D_Minal);
9187 Set_Discriminal_Link (D_Minal, Discrim);
9189 -- For task types, build at once the discriminants of the corresponding
9190 -- record, which are needed if discriminants are used in entry defaults
9191 -- and in family bounds.
9193 if Is_Concurrent_Type (Current_Scope)
9195 Is_Limited_Type (Current_Scope)
9197 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9199 Set_Ekind (CR_Disc, E_In_Parameter);
9200 Set_Mechanism (CR_Disc, Default_Mechanism);
9201 Set_Etype (CR_Disc, Etype (Discrim));
9202 Set_Scope (CR_Disc, Current_Scope);
9203 Set_Discriminal_Link (CR_Disc, Discrim);
9204 Set_CR_Discriminant (Discrim, CR_Disc);
9206 end Build_Discriminal;
9208 ------------------------------------
9209 -- Build_Discriminant_Constraints --
9210 ------------------------------------
9212 function Build_Discriminant_Constraints
9215 Derived_Def : Boolean := False) return Elist_Id
9217 C : constant Node_Id := Constraint (Def);
9218 Nb_Discr : constant Nat := Number_Discriminants (T);
9220 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9221 -- Saves the expression corresponding to a given discriminant in T
9223 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9224 -- Return the Position number within array Discr_Expr of a discriminant
9225 -- D within the discriminant list of the discriminated type T.
9227 procedure Process_Discriminant_Expression
9230 -- If this is a discriminant constraint on a partial view, do not
9231 -- generate an overflow check on the discriminant expression. The check
9232 -- will be generated when constraining the full view. Otherwise the
9233 -- backend creates duplicate symbols for the temporaries corresponding
9234 -- to the expressions to be checked, causing spurious assembler errors.
9240 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9244 Disc := First_Discriminant (T);
9245 for J in Discr_Expr'Range loop
9250 Next_Discriminant (Disc);
9253 -- Note: Since this function is called on discriminants that are
9254 -- known to belong to the discriminated type, falling through the
9255 -- loop with no match signals an internal compiler error.
9257 raise Program_Error;
9260 -------------------------------------
9261 -- Process_Discriminant_Expression --
9262 -------------------------------------
9264 procedure Process_Discriminant_Expression
9268 BDT : constant Entity_Id := Base_Type (Etype (D));
9271 -- If this is a discriminant constraint on a partial view, do
9272 -- not generate an overflow on the discriminant expression. The
9273 -- check will be generated when constraining the full view.
9275 if Is_Private_Type (T)
9276 and then Present (Full_View (T))
9278 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9280 Analyze_And_Resolve (Expr, BDT);
9282 end Process_Discriminant_Expression;
9284 -- Declarations local to Build_Discriminant_Constraints
9288 Elist : constant Elist_Id := New_Elmt_List;
9296 Discrim_Present : Boolean := False;
9298 -- Start of processing for Build_Discriminant_Constraints
9301 -- The following loop will process positional associations only.
9302 -- For a positional association, the (single) discriminant is
9303 -- implicitly specified by position, in textual order (RM 3.7.2).
9305 Discr := First_Discriminant (T);
9306 Constr := First (Constraints (C));
9307 for D in Discr_Expr'Range loop
9308 exit when Nkind (Constr) = N_Discriminant_Association;
9311 Error_Msg_N ("too few discriminants given in constraint", C);
9312 return New_Elmt_List;
9314 elsif Nkind (Constr) = N_Range
9315 or else (Nkind (Constr) = N_Attribute_Reference
9316 and then Attribute_Name (Constr) = Name_Range)
9319 ("a range is not a valid discriminant constraint", Constr);
9320 Discr_Expr (D) := Error;
9323 Process_Discriminant_Expression (Constr, Discr);
9324 Discr_Expr (D) := Constr;
9327 Next_Discriminant (Discr);
9331 if No (Discr) and then Present (Constr) then
9332 Error_Msg_N ("too many discriminants given in constraint", Constr);
9333 return New_Elmt_List;
9336 -- Named associations can be given in any order, but if both positional
9337 -- and named associations are used in the same discriminant constraint,
9338 -- then positional associations must occur first, at their normal
9339 -- position. Hence once a named association is used, the rest of the
9340 -- discriminant constraint must use only named associations.
9342 while Present (Constr) loop
9344 -- Positional association forbidden after a named association
9346 if Nkind (Constr) /= N_Discriminant_Association then
9347 Error_Msg_N ("positional association follows named one", Constr);
9348 return New_Elmt_List;
9350 -- Otherwise it is a named association
9353 -- E records the type of the discriminants in the named
9354 -- association. All the discriminants specified in the same name
9355 -- association must have the same type.
9359 -- Search the list of discriminants in T to see if the simple name
9360 -- given in the constraint matches any of them.
9362 Id := First (Selector_Names (Constr));
9363 while Present (Id) loop
9366 -- If Original_Discriminant is present, we are processing a
9367 -- generic instantiation and this is an instance node. We need
9368 -- to find the name of the corresponding discriminant in the
9369 -- actual record type T and not the name of the discriminant in
9370 -- the generic formal. Example:
9373 -- type G (D : int) is private;
9375 -- subtype W is G (D => 1);
9377 -- type Rec (X : int) is record ... end record;
9378 -- package Q is new P (G => Rec);
9380 -- At the point of the instantiation, formal type G is Rec
9381 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9382 -- which really looks like "subtype W is Rec (D => 1);" at
9383 -- the point of instantiation, we want to find the discriminant
9384 -- that corresponds to D in Rec, i.e. X.
9386 if Present (Original_Discriminant (Id))
9387 and then In_Instance
9389 Discr := Find_Corresponding_Discriminant (Id, T);
9393 Discr := First_Discriminant (T);
9394 while Present (Discr) loop
9395 if Chars (Discr) = Chars (Id) then
9400 Next_Discriminant (Discr);
9404 Error_Msg_N ("& does not match any discriminant", Id);
9405 return New_Elmt_List;
9407 -- If the parent type is a generic formal, preserve the
9408 -- name of the discriminant for subsequent instances.
9409 -- see comment at the beginning of this if statement.
9411 elsif Is_Generic_Type (Root_Type (T)) then
9412 Set_Original_Discriminant (Id, Discr);
9416 Position := Pos_Of_Discr (T, Discr);
9418 if Present (Discr_Expr (Position)) then
9419 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9422 -- Each discriminant specified in the same named association
9423 -- must be associated with a separate copy of the
9424 -- corresponding expression.
9426 if Present (Next (Id)) then
9427 Expr := New_Copy_Tree (Expression (Constr));
9428 Set_Parent (Expr, Parent (Expression (Constr)));
9430 Expr := Expression (Constr);
9433 Discr_Expr (Position) := Expr;
9434 Process_Discriminant_Expression (Expr, Discr);
9437 -- A discriminant association with more than one discriminant
9438 -- name is only allowed if the named discriminants are all of
9439 -- the same type (RM 3.7.1(8)).
9442 E := Base_Type (Etype (Discr));
9444 elsif Base_Type (Etype (Discr)) /= E then
9446 ("all discriminants in an association " &
9447 "must have the same type", Id);
9457 -- A discriminant constraint must provide exactly one value for each
9458 -- discriminant of the type (RM 3.7.1(8)).
9460 for J in Discr_Expr'Range loop
9461 if No (Discr_Expr (J)) then
9462 Error_Msg_N ("too few discriminants given in constraint", C);
9463 return New_Elmt_List;
9467 -- Determine if there are discriminant expressions in the constraint
9469 for J in Discr_Expr'Range loop
9470 if Denotes_Discriminant
9471 (Discr_Expr (J), Check_Concurrent => True)
9473 Discrim_Present := True;
9477 -- Build an element list consisting of the expressions given in the
9478 -- discriminant constraint and apply the appropriate checks. The list
9479 -- is constructed after resolving any named discriminant associations
9480 -- and therefore the expressions appear in the textual order of the
9483 Discr := First_Discriminant (T);
9484 for J in Discr_Expr'Range loop
9485 if Discr_Expr (J) /= Error then
9486 Append_Elmt (Discr_Expr (J), Elist);
9488 -- If any of the discriminant constraints is given by a
9489 -- discriminant and we are in a derived type declaration we
9490 -- have a discriminant renaming. Establish link between new
9491 -- and old discriminant.
9493 if Denotes_Discriminant (Discr_Expr (J)) then
9495 Set_Corresponding_Discriminant
9496 (Entity (Discr_Expr (J)), Discr);
9499 -- Force the evaluation of non-discriminant expressions.
9500 -- If we have found a discriminant in the constraint 3.4(26)
9501 -- and 3.8(18) demand that no range checks are performed are
9502 -- after evaluation. If the constraint is for a component
9503 -- definition that has a per-object constraint, expressions are
9504 -- evaluated but not checked either. In all other cases perform
9508 if Discrim_Present then
9511 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9513 Has_Per_Object_Constraint
9514 (Defining_Identifier (Parent (Parent (Def))))
9518 elsif Is_Access_Type (Etype (Discr)) then
9519 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9522 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9525 Force_Evaluation (Discr_Expr (J));
9528 -- Check that the designated type of an access discriminant's
9529 -- expression is not a class-wide type unless the discriminant's
9530 -- designated type is also class-wide.
9532 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9533 and then not Is_Class_Wide_Type
9534 (Designated_Type (Etype (Discr)))
9535 and then Etype (Discr_Expr (J)) /= Any_Type
9536 and then Is_Class_Wide_Type
9537 (Designated_Type (Etype (Discr_Expr (J))))
9539 Wrong_Type (Discr_Expr (J), Etype (Discr));
9541 elsif Is_Access_Type (Etype (Discr))
9542 and then not Is_Access_Constant (Etype (Discr))
9543 and then Is_Access_Type (Etype (Discr_Expr (J)))
9544 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9547 ("constraint for discriminant& must be access to variable",
9552 Next_Discriminant (Discr);
9556 end Build_Discriminant_Constraints;
9558 ---------------------------------
9559 -- Build_Discriminated_Subtype --
9560 ---------------------------------
9562 procedure Build_Discriminated_Subtype
9566 Related_Nod : Node_Id;
9567 For_Access : Boolean := False)
9569 Has_Discrs : constant Boolean := Has_Discriminants (T);
9570 Constrained : constant Boolean :=
9572 and then not Is_Empty_Elmt_List (Elist)
9573 and then not Is_Class_Wide_Type (T))
9574 or else Is_Constrained (T);
9577 if Ekind (T) = E_Record_Type then
9579 Set_Ekind (Def_Id, E_Private_Subtype);
9580 Set_Is_For_Access_Subtype (Def_Id, True);
9582 Set_Ekind (Def_Id, E_Record_Subtype);
9585 -- Inherit preelaboration flag from base, for types for which it
9586 -- may have been set: records, private types, protected types.
9588 Set_Known_To_Have_Preelab_Init
9589 (Def_Id, Known_To_Have_Preelab_Init (T));
9591 elsif Ekind (T) = E_Task_Type then
9592 Set_Ekind (Def_Id, E_Task_Subtype);
9594 elsif Ekind (T) = E_Protected_Type then
9595 Set_Ekind (Def_Id, E_Protected_Subtype);
9596 Set_Known_To_Have_Preelab_Init
9597 (Def_Id, Known_To_Have_Preelab_Init (T));
9599 elsif Is_Private_Type (T) then
9600 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9601 Set_Known_To_Have_Preelab_Init
9602 (Def_Id, Known_To_Have_Preelab_Init (T));
9604 -- Private subtypes may have private dependents
9606 Set_Private_Dependents (Def_Id, New_Elmt_List);
9608 elsif Is_Class_Wide_Type (T) then
9609 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9612 -- Incomplete type. Attach subtype to list of dependents, to be
9613 -- completed with full view of parent type, unless is it the
9614 -- designated subtype of a record component within an init_proc.
9615 -- This last case arises for a component of an access type whose
9616 -- designated type is incomplete (e.g. a Taft Amendment type).
9617 -- The designated subtype is within an inner scope, and needs no
9618 -- elaboration, because only the access type is needed in the
9619 -- initialization procedure.
9621 Set_Ekind (Def_Id, Ekind (T));
9623 if For_Access and then Within_Init_Proc then
9626 Append_Elmt (Def_Id, Private_Dependents (T));
9630 Set_Etype (Def_Id, T);
9631 Init_Size_Align (Def_Id);
9632 Set_Has_Discriminants (Def_Id, Has_Discrs);
9633 Set_Is_Constrained (Def_Id, Constrained);
9635 Set_First_Entity (Def_Id, First_Entity (T));
9636 Set_Last_Entity (Def_Id, Last_Entity (T));
9637 Set_Has_Implicit_Dereference
9638 (Def_Id, Has_Implicit_Dereference (T));
9640 -- If the subtype is the completion of a private declaration, there may
9641 -- have been representation clauses for the partial view, and they must
9642 -- be preserved. Build_Derived_Type chains the inherited clauses with
9643 -- the ones appearing on the extension. If this comes from a subtype
9644 -- declaration, all clauses are inherited.
9646 if No (First_Rep_Item (Def_Id)) then
9647 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9650 if Is_Tagged_Type (T) then
9651 Set_Is_Tagged_Type (Def_Id);
9652 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9653 Make_Class_Wide_Type (Def_Id);
9656 Set_Stored_Constraint (Def_Id, No_Elist);
9659 Set_Discriminant_Constraint (Def_Id, Elist);
9660 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9663 if Is_Tagged_Type (T) then
9665 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9666 -- concurrent record type (which has the list of primitive
9669 if Ada_Version >= Ada_2005
9670 and then Is_Concurrent_Type (T)
9672 Set_Corresponding_Record_Type (Def_Id,
9673 Corresponding_Record_Type (T));
9675 Set_Direct_Primitive_Operations (Def_Id,
9676 Direct_Primitive_Operations (T));
9679 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9682 -- Subtypes introduced by component declarations do not need to be
9683 -- marked as delayed, and do not get freeze nodes, because the semantics
9684 -- verifies that the parents of the subtypes are frozen before the
9685 -- enclosing record is frozen.
9687 if not Is_Type (Scope (Def_Id)) then
9688 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9690 if Is_Private_Type (T)
9691 and then Present (Full_View (T))
9693 Conditional_Delay (Def_Id, Full_View (T));
9695 Conditional_Delay (Def_Id, T);
9699 if Is_Record_Type (T) then
9700 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9703 and then not Is_Empty_Elmt_List (Elist)
9704 and then not For_Access
9706 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9707 elsif not For_Access then
9708 Set_Cloned_Subtype (Def_Id, T);
9711 end Build_Discriminated_Subtype;
9713 ---------------------------
9714 -- Build_Itype_Reference --
9715 ---------------------------
9717 procedure Build_Itype_Reference
9721 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9724 -- Itype references are only created for use by the back-end
9726 if Inside_A_Generic then
9729 Set_Itype (IR, Ityp);
9730 Insert_After (Nod, IR);
9732 end Build_Itype_Reference;
9734 ------------------------
9735 -- Build_Scalar_Bound --
9736 ------------------------
9738 function Build_Scalar_Bound
9741 Der_T : Entity_Id) return Node_Id
9743 New_Bound : Entity_Id;
9746 -- Note: not clear why this is needed, how can the original bound
9747 -- be unanalyzed at this point? and if it is, what business do we
9748 -- have messing around with it? and why is the base type of the
9749 -- parent type the right type for the resolution. It probably is
9750 -- not. It is OK for the new bound we are creating, but not for
9751 -- the old one??? Still if it never happens, no problem.
9753 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9755 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9756 New_Bound := New_Copy (Bound);
9757 Set_Etype (New_Bound, Der_T);
9758 Set_Analyzed (New_Bound);
9760 elsif Is_Entity_Name (Bound) then
9761 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9763 -- The following is almost certainly wrong. What business do we have
9764 -- relocating a node (Bound) that is presumably still attached to
9765 -- the tree elsewhere???
9768 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9771 Set_Etype (New_Bound, Der_T);
9773 end Build_Scalar_Bound;
9775 --------------------------------
9776 -- Build_Underlying_Full_View --
9777 --------------------------------
9779 procedure Build_Underlying_Full_View
9784 Loc : constant Source_Ptr := Sloc (N);
9785 Subt : constant Entity_Id :=
9786 Make_Defining_Identifier
9787 (Loc, New_External_Name (Chars (Typ), 'S'));
9794 procedure Set_Discriminant_Name (Id : Node_Id);
9795 -- If the derived type has discriminants, they may rename discriminants
9796 -- of the parent. When building the full view of the parent, we need to
9797 -- recover the names of the original discriminants if the constraint is
9798 -- given by named associations.
9800 ---------------------------
9801 -- Set_Discriminant_Name --
9802 ---------------------------
9804 procedure Set_Discriminant_Name (Id : Node_Id) is
9808 Set_Original_Discriminant (Id, Empty);
9810 if Has_Discriminants (Typ) then
9811 Disc := First_Discriminant (Typ);
9812 while Present (Disc) loop
9813 if Chars (Disc) = Chars (Id)
9814 and then Present (Corresponding_Discriminant (Disc))
9816 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9818 Next_Discriminant (Disc);
9821 end Set_Discriminant_Name;
9823 -- Start of processing for Build_Underlying_Full_View
9826 if Nkind (N) = N_Full_Type_Declaration then
9827 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9829 elsif Nkind (N) = N_Subtype_Declaration then
9830 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9832 elsif Nkind (N) = N_Component_Declaration then
9835 (Constraint (Subtype_Indication (Component_Definition (N))));
9838 raise Program_Error;
9841 C := First (Constraints (Constr));
9842 while Present (C) loop
9843 if Nkind (C) = N_Discriminant_Association then
9844 Id := First (Selector_Names (C));
9845 while Present (Id) loop
9846 Set_Discriminant_Name (Id);
9855 Make_Subtype_Declaration (Loc,
9856 Defining_Identifier => Subt,
9857 Subtype_Indication =>
9858 Make_Subtype_Indication (Loc,
9859 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9860 Constraint => New_Copy_Tree (Constr)));
9862 -- If this is a component subtype for an outer itype, it is not
9863 -- a list member, so simply set the parent link for analysis: if
9864 -- the enclosing type does not need to be in a declarative list,
9865 -- neither do the components.
9867 if Is_List_Member (N)
9868 and then Nkind (N) /= N_Component_Declaration
9870 Insert_Before (N, Indic);
9872 Set_Parent (Indic, Parent (N));
9876 Set_Underlying_Full_View (Typ, Full_View (Subt));
9877 end Build_Underlying_Full_View;
9879 -------------------------------
9880 -- Check_Abstract_Overriding --
9881 -------------------------------
9883 procedure Check_Abstract_Overriding (T : Entity_Id) is
9884 Alias_Subp : Entity_Id;
9890 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9891 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9892 -- which has pragma Implemented already set. Check whether Subp's entity
9893 -- kind conforms to the implementation kind of the overridden routine.
9895 procedure Check_Pragma_Implemented
9897 Iface_Subp : Entity_Id);
9898 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9899 -- Iface_Subp and both entities have pragma Implemented already set on
9900 -- them. Check whether the two implementation kinds are conforming.
9902 procedure Inherit_Pragma_Implemented
9904 Iface_Subp : Entity_Id);
9905 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9906 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9907 -- Propagate the implementation kind of Iface_Subp to Subp.
9909 ------------------------------
9910 -- Check_Pragma_Implemented --
9911 ------------------------------
9913 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9914 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9915 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9916 Subp_Alias : constant Entity_Id := Alias (Subp);
9917 Contr_Typ : Entity_Id;
9918 Impl_Subp : Entity_Id;
9921 -- Subp must have an alias since it is a hidden entity used to link
9922 -- an interface subprogram to its overriding counterpart.
9924 pragma Assert (Present (Subp_Alias));
9926 -- Handle aliases to synchronized wrappers
9928 Impl_Subp := Subp_Alias;
9930 if Is_Primitive_Wrapper (Impl_Subp) then
9931 Impl_Subp := Wrapped_Entity (Impl_Subp);
9934 -- Extract the type of the controlling formal
9936 Contr_Typ := Etype (First_Formal (Subp_Alias));
9938 if Is_Concurrent_Record_Type (Contr_Typ) then
9939 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9942 -- An interface subprogram whose implementation kind is By_Entry must
9943 -- be implemented by an entry.
9945 if Impl_Kind = Name_By_Entry
9946 and then Ekind (Impl_Subp) /= E_Entry
9948 Error_Msg_Node_2 := Iface_Alias;
9950 ("type & must implement abstract subprogram & with an entry",
9951 Subp_Alias, Contr_Typ);
9953 elsif Impl_Kind = Name_By_Protected_Procedure then
9955 -- An interface subprogram whose implementation kind is By_
9956 -- Protected_Procedure cannot be implemented by a primitive
9957 -- procedure of a task type.
9959 if Ekind (Contr_Typ) /= E_Protected_Type then
9960 Error_Msg_Node_2 := Contr_Typ;
9962 ("interface subprogram & cannot be implemented by a " &
9963 "primitive procedure of task type &", Subp_Alias,
9966 -- An interface subprogram whose implementation kind is By_
9967 -- Protected_Procedure must be implemented by a procedure.
9969 elsif Ekind (Impl_Subp) /= E_Procedure then
9970 Error_Msg_Node_2 := Iface_Alias;
9972 ("type & must implement abstract subprogram & with a " &
9973 "procedure", Subp_Alias, Contr_Typ);
9975 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9976 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9978 Error_Msg_Name_1 := Impl_Kind;
9980 ("overriding operation& must have synchronization%",
9984 -- If primitive has Optional synchronization, overriding operation
9985 -- must match if it has an explicit synchronization..
9987 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9988 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9990 Error_Msg_Name_1 := Impl_Kind;
9992 ("overriding operation& must have syncrhonization%",
9995 end Check_Pragma_Implemented;
9997 ------------------------------
9998 -- Check_Pragma_Implemented --
9999 ------------------------------
10001 procedure Check_Pragma_Implemented
10003 Iface_Subp : Entity_Id)
10005 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10006 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
10009 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
10010 -- and overriding subprogram are different. In general this is an
10011 -- error except when the implementation kind of the overridden
10012 -- subprograms is By_Any or Optional.
10014 if Iface_Kind /= Subp_Kind
10015 and then Iface_Kind /= Name_By_Any
10016 and then Iface_Kind /= Name_Optional
10018 if Iface_Kind = Name_By_Entry then
10020 ("incompatible implementation kind, overridden subprogram " &
10021 "is marked By_Entry", Subp);
10024 ("incompatible implementation kind, overridden subprogram " &
10025 "is marked By_Protected_Procedure", Subp);
10028 end Check_Pragma_Implemented;
10030 --------------------------------
10031 -- Inherit_Pragma_Implemented --
10032 --------------------------------
10034 procedure Inherit_Pragma_Implemented
10036 Iface_Subp : Entity_Id)
10038 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10039 Loc : constant Source_Ptr := Sloc (Subp);
10040 Impl_Prag : Node_Id;
10043 -- Since the implementation kind is stored as a representation item
10044 -- rather than a flag, create a pragma node.
10048 Chars => Name_Implemented,
10049 Pragma_Argument_Associations => New_List (
10050 Make_Pragma_Argument_Association (Loc,
10051 Expression => New_Occurrence_Of (Subp, Loc)),
10053 Make_Pragma_Argument_Association (Loc,
10054 Expression => Make_Identifier (Loc, Iface_Kind))));
10056 -- The pragma doesn't need to be analyzed because it is internally
10057 -- built. It is safe to directly register it as a rep item since we
10058 -- are only interested in the characters of the implementation kind.
10060 Record_Rep_Item (Subp, Impl_Prag);
10061 end Inherit_Pragma_Implemented;
10063 -- Start of processing for Check_Abstract_Overriding
10066 Op_List := Primitive_Operations (T);
10068 -- Loop to check primitive operations
10070 Elmt := First_Elmt (Op_List);
10071 while Present (Elmt) loop
10072 Subp := Node (Elmt);
10073 Alias_Subp := Alias (Subp);
10075 -- Inherited subprograms are identified by the fact that they do not
10076 -- come from source, and the associated source location is the
10077 -- location of the first subtype of the derived type.
10079 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
10080 -- subprograms that "require overriding".
10082 -- Special exception, do not complain about failure to override the
10083 -- stream routines _Input and _Output, as well as the primitive
10084 -- operations used in dispatching selects since we always provide
10085 -- automatic overridings for these subprograms.
10087 -- The partial view of T may have been a private extension, for
10088 -- which inherited functions dispatching on result are abstract.
10089 -- If the full view is a null extension, there is no need for
10090 -- overriding in Ada 2005, but wrappers need to be built for them
10091 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10093 if Is_Null_Extension (T)
10094 and then Has_Controlling_Result (Subp)
10095 and then Ada_Version >= Ada_2005
10096 and then Present (Alias_Subp)
10097 and then not Comes_From_Source (Subp)
10098 and then not Is_Abstract_Subprogram (Alias_Subp)
10099 and then not Is_Access_Type (Etype (Subp))
10103 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10104 -- processing because this check is done with the aliased
10107 elsif Present (Interface_Alias (Subp)) then
10110 elsif (Is_Abstract_Subprogram (Subp)
10111 or else Requires_Overriding (Subp)
10113 (Has_Controlling_Result (Subp)
10114 and then Present (Alias_Subp)
10115 and then not Comes_From_Source (Subp)
10116 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10117 and then not Is_TSS (Subp, TSS_Stream_Input)
10118 and then not Is_TSS (Subp, TSS_Stream_Output)
10119 and then not Is_Abstract_Type (T)
10120 and then not Is_Predefined_Interface_Primitive (Subp)
10122 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10123 -- with abstract interface types because the check will be done
10124 -- with the aliased entity (otherwise we generate a duplicated
10127 and then not Present (Interface_Alias (Subp))
10129 if Present (Alias_Subp) then
10131 -- Only perform the check for a derived subprogram when the
10132 -- type has an explicit record extension. This avoids incorrect
10133 -- flagging of abstract subprograms for the case of a type
10134 -- without an extension that is derived from a formal type
10135 -- with a tagged actual (can occur within a private part).
10137 -- Ada 2005 (AI-391): In the case of an inherited function with
10138 -- a controlling result of the type, the rule does not apply if
10139 -- the type is a null extension (unless the parent function
10140 -- itself is abstract, in which case the function must still be
10141 -- be overridden). The expander will generate an overriding
10142 -- wrapper function calling the parent subprogram (see
10143 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10145 Type_Def := Type_Definition (Parent (T));
10147 if Nkind (Type_Def) = N_Derived_Type_Definition
10148 and then Present (Record_Extension_Part (Type_Def))
10150 (Ada_Version < Ada_2005
10151 or else not Is_Null_Extension (T)
10152 or else Ekind (Subp) = E_Procedure
10153 or else not Has_Controlling_Result (Subp)
10154 or else Is_Abstract_Subprogram (Alias_Subp)
10155 or else Requires_Overriding (Subp)
10156 or else Is_Access_Type (Etype (Subp)))
10158 -- Avoid reporting error in case of abstract predefined
10159 -- primitive inherited from interface type because the
10160 -- body of internally generated predefined primitives
10161 -- of tagged types are generated later by Freeze_Type
10163 if Is_Interface (Root_Type (T))
10164 and then Is_Abstract_Subprogram (Subp)
10165 and then Is_Predefined_Dispatching_Operation (Subp)
10166 and then not Comes_From_Source (Ultimate_Alias (Subp))
10170 -- A null extension is not obliged to override an inherited
10171 -- procedure subject to pragma Extensions_Visible with value
10172 -- False and at least one controlling OUT parameter
10173 -- (SPARK RM 6.1.7(6)).
10175 elsif Is_Null_Extension (T)
10176 and then Is_EVF_Procedure (Subp)
10182 ("type must be declared abstract or & overridden",
10185 -- Traverse the whole chain of aliased subprograms to
10186 -- complete the error notification. This is especially
10187 -- useful for traceability of the chain of entities when
10188 -- the subprogram corresponds with an interface
10189 -- subprogram (which may be defined in another package).
10191 if Present (Alias_Subp) then
10197 while Present (Alias (E)) loop
10199 -- Avoid reporting redundant errors on entities
10200 -- inherited from interfaces
10202 if Sloc (E) /= Sloc (T) then
10203 Error_Msg_Sloc := Sloc (E);
10205 ("\& has been inherited #", T, Subp);
10211 Error_Msg_Sloc := Sloc (E);
10213 -- AI05-0068: report if there is an overriding
10214 -- non-abstract subprogram that is invisible.
10217 and then not Is_Abstract_Subprogram (E)
10220 ("\& subprogram# is not visible",
10223 -- Clarify the case where a non-null extension must
10224 -- override inherited procedure subject to pragma
10225 -- Extensions_Visible with value False and at least
10226 -- one controlling OUT param.
10228 elsif Is_EVF_Procedure (E) then
10230 ("\& # is subject to Extensions_Visible False",
10235 ("\& has been inherited from subprogram #",
10242 -- Ada 2005 (AI-345): Protected or task type implementing
10243 -- abstract interfaces.
10245 elsif Is_Concurrent_Record_Type (T)
10246 and then Present (Interfaces (T))
10248 -- There is no need to check here RM 9.4(11.9/3) since we
10249 -- are processing the corresponding record type and the
10250 -- mode of the overriding subprograms was verified by
10251 -- Check_Conformance when the corresponding concurrent
10252 -- type declaration was analyzed.
10255 ("interface subprogram & must be overridden", T, Subp);
10257 -- Examine primitive operations of synchronized type to find
10258 -- homonyms that have the wrong profile.
10264 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10265 while Present (Prim) loop
10266 if Chars (Prim) = Chars (Subp) then
10268 ("profile is not type conformant with prefixed "
10269 & "view profile of inherited operation&",
10273 Next_Entity (Prim);
10279 Error_Msg_Node_2 := T;
10281 ("abstract subprogram& not allowed for type&", Subp);
10283 -- Also post unconditional warning on the type (unconditional
10284 -- so that if there are more than one of these cases, we get
10285 -- them all, and not just the first one).
10287 Error_Msg_Node_2 := Subp;
10288 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10291 -- A subprogram subject to pragma Extensions_Visible with value
10292 -- "True" cannot override a subprogram subject to the same pragma
10293 -- with value "False" (SPARK RM 6.1.7(5)).
10295 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10296 and then Present (Overridden_Operation (Subp))
10297 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10298 Extensions_Visible_False
10300 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10302 ("subprogram & with Extensions_Visible True cannot override "
10303 & "subprogram # with Extensions_Visible False", Subp);
10306 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10308 -- Subp is an expander-generated procedure which maps an interface
10309 -- alias to a protected wrapper. The interface alias is flagged by
10310 -- pragma Implemented. Ensure that Subp is a procedure when the
10311 -- implementation kind is By_Protected_Procedure or an entry when
10314 if Ada_Version >= Ada_2012
10315 and then Is_Hidden (Subp)
10316 and then Present (Interface_Alias (Subp))
10317 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10319 Check_Pragma_Implemented (Subp);
10322 -- Subp is an interface primitive which overrides another interface
10323 -- primitive marked with pragma Implemented.
10325 if Ada_Version >= Ada_2012
10326 and then Present (Overridden_Operation (Subp))
10327 and then Has_Rep_Pragma
10328 (Overridden_Operation (Subp), Name_Implemented)
10330 -- If the overriding routine is also marked by Implemented, check
10331 -- that the two implementation kinds are conforming.
10333 if Has_Rep_Pragma (Subp, Name_Implemented) then
10334 Check_Pragma_Implemented
10336 Iface_Subp => Overridden_Operation (Subp));
10338 -- Otherwise the overriding routine inherits the implementation
10339 -- kind from the overridden subprogram.
10342 Inherit_Pragma_Implemented
10344 Iface_Subp => Overridden_Operation (Subp));
10348 -- If the operation is a wrapper for a synchronized primitive, it
10349 -- may be called indirectly through a dispatching select. We assume
10350 -- that it will be referenced elsewhere indirectly, and suppress
10351 -- warnings about an unused entity.
10353 if Is_Primitive_Wrapper (Subp)
10354 and then Present (Wrapped_Entity (Subp))
10356 Set_Referenced (Wrapped_Entity (Subp));
10361 end Check_Abstract_Overriding;
10363 ------------------------------------------------
10364 -- Check_Access_Discriminant_Requires_Limited --
10365 ------------------------------------------------
10367 procedure Check_Access_Discriminant_Requires_Limited
10372 -- A discriminant_specification for an access discriminant shall appear
10373 -- only in the declaration for a task or protected type, or for a type
10374 -- with the reserved word 'limited' in its definition or in one of its
10375 -- ancestors (RM 3.7(10)).
10377 -- AI-0063: The proper condition is that type must be immutably limited,
10378 -- or else be a partial view.
10380 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10381 if Is_Limited_View (Current_Scope)
10383 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10384 and then Limited_Present (Parent (Current_Scope)))
10390 ("access discriminants allowed only for limited types", Loc);
10393 end Check_Access_Discriminant_Requires_Limited;
10395 -----------------------------------
10396 -- Check_Aliased_Component_Types --
10397 -----------------------------------
10399 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10403 -- ??? Also need to check components of record extensions, but not
10404 -- components of protected types (which are always limited).
10406 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10407 -- types to be unconstrained. This is safe because it is illegal to
10408 -- create access subtypes to such types with explicit discriminant
10411 if not Is_Limited_Type (T) then
10412 if Ekind (T) = E_Record_Type then
10413 C := First_Component (T);
10414 while Present (C) loop
10416 and then Has_Discriminants (Etype (C))
10417 and then not Is_Constrained (Etype (C))
10418 and then not In_Instance_Body
10419 and then Ada_Version < Ada_2005
10422 ("aliased component must be constrained (RM 3.6(11))",
10426 Next_Component (C);
10429 elsif Ekind (T) = E_Array_Type then
10430 if Has_Aliased_Components (T)
10431 and then Has_Discriminants (Component_Type (T))
10432 and then not Is_Constrained (Component_Type (T))
10433 and then not In_Instance_Body
10434 and then Ada_Version < Ada_2005
10437 ("aliased component type must be constrained (RM 3.6(11))",
10442 end Check_Aliased_Component_Types;
10444 ---------------------------------------
10445 -- Check_Anonymous_Access_Components --
10446 ---------------------------------------
10448 procedure Check_Anonymous_Access_Components
10449 (Typ_Decl : Node_Id;
10452 Comp_List : Node_Id)
10454 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10455 Anon_Access : Entity_Id;
10458 Comp_Def : Node_Id;
10460 Type_Def : Node_Id;
10462 procedure Build_Incomplete_Type_Declaration;
10463 -- If the record type contains components that include an access to the
10464 -- current record, then create an incomplete type declaration for the
10465 -- record, to be used as the designated type of the anonymous access.
10466 -- This is done only once, and only if there is no previous partial
10467 -- view of the type.
10469 function Designates_T (Subt : Node_Id) return Boolean;
10470 -- Check whether a node designates the enclosing record type, or 'Class
10473 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10474 -- Check whether an access definition includes a reference to
10475 -- the enclosing record type. The reference can be a subtype mark
10476 -- in the access definition itself, a 'Class attribute reference, or
10477 -- recursively a reference appearing in a parameter specification
10478 -- or result definition of an access_to_subprogram definition.
10480 --------------------------------------
10481 -- Build_Incomplete_Type_Declaration --
10482 --------------------------------------
10484 procedure Build_Incomplete_Type_Declaration is
10489 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10490 -- it's "is new ... with record" or else "is tagged record ...".
10492 Is_Tagged : constant Boolean :=
10493 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10495 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10497 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10498 and then Tagged_Present (Type_Definition (Typ_Decl)));
10501 -- If there is a previous partial view, no need to create a new one
10502 -- If the partial view, given by Prev, is incomplete, If Prev is
10503 -- a private declaration, full declaration is flagged accordingly.
10505 if Prev /= Typ then
10507 Make_Class_Wide_Type (Prev);
10508 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10509 Set_Etype (Class_Wide_Type (Typ), Typ);
10514 elsif Has_Private_Declaration (Typ) then
10516 -- If we refer to T'Class inside T, and T is the completion of a
10517 -- private type, then make sure the class-wide type exists.
10520 Make_Class_Wide_Type (Typ);
10525 -- If there was a previous anonymous access type, the incomplete
10526 -- type declaration will have been created already.
10528 elsif Present (Current_Entity (Typ))
10529 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10530 and then Full_View (Current_Entity (Typ)) = Typ
10533 and then Comes_From_Source (Current_Entity (Typ))
10534 and then not Is_Tagged_Type (Current_Entity (Typ))
10536 Make_Class_Wide_Type (Typ);
10538 ("incomplete view of tagged type should be declared tagged??",
10539 Parent (Current_Entity (Typ)));
10544 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10545 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10547 -- Type has already been inserted into the current scope. Remove
10548 -- it, and add incomplete declaration for type, so that subsequent
10549 -- anonymous access types can use it. The entity is unchained from
10550 -- the homonym list and from immediate visibility. After analysis,
10551 -- the entity in the incomplete declaration becomes immediately
10552 -- visible in the record declaration that follows.
10554 H := Current_Entity (Typ);
10557 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10560 and then Homonym (H) /= Typ
10562 H := Homonym (Typ);
10565 Set_Homonym (H, Homonym (Typ));
10568 Insert_Before (Typ_Decl, Decl);
10570 Set_Full_View (Inc_T, Typ);
10574 -- Create a common class-wide type for both views, and set the
10575 -- Etype of the class-wide type to the full view.
10577 Make_Class_Wide_Type (Inc_T);
10578 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10579 Set_Etype (Class_Wide_Type (Typ), Typ);
10582 end Build_Incomplete_Type_Declaration;
10588 function Designates_T (Subt : Node_Id) return Boolean is
10589 Type_Id : constant Name_Id := Chars (Typ);
10591 function Names_T (Nam : Node_Id) return Boolean;
10592 -- The record type has not been introduced in the current scope
10593 -- yet, so we must examine the name of the type itself, either
10594 -- an identifier T, or an expanded name of the form P.T, where
10595 -- P denotes the current scope.
10601 function Names_T (Nam : Node_Id) return Boolean is
10603 if Nkind (Nam) = N_Identifier then
10604 return Chars (Nam) = Type_Id;
10606 elsif Nkind (Nam) = N_Selected_Component then
10607 if Chars (Selector_Name (Nam)) = Type_Id then
10608 if Nkind (Prefix (Nam)) = N_Identifier then
10609 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10611 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10612 return Chars (Selector_Name (Prefix (Nam))) =
10613 Chars (Current_Scope);
10627 -- Start of processing for Designates_T
10630 if Nkind (Subt) = N_Identifier then
10631 return Chars (Subt) = Type_Id;
10633 -- Reference can be through an expanded name which has not been
10634 -- analyzed yet, and which designates enclosing scopes.
10636 elsif Nkind (Subt) = N_Selected_Component then
10637 if Names_T (Subt) then
10640 -- Otherwise it must denote an entity that is already visible.
10641 -- The access definition may name a subtype of the enclosing
10642 -- type, if there is a previous incomplete declaration for it.
10645 Find_Selected_Component (Subt);
10647 Is_Entity_Name (Subt)
10648 and then Scope (Entity (Subt)) = Current_Scope
10650 (Chars (Base_Type (Entity (Subt))) = Type_Id
10652 (Is_Class_Wide_Type (Entity (Subt))
10654 Chars (Etype (Base_Type (Entity (Subt)))) =
10658 -- A reference to the current type may appear as the prefix of
10659 -- a 'Class attribute.
10661 elsif Nkind (Subt) = N_Attribute_Reference
10662 and then Attribute_Name (Subt) = Name_Class
10664 return Names_T (Prefix (Subt));
10675 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10676 Param_Spec : Node_Id;
10678 Acc_Subprg : constant Node_Id :=
10679 Access_To_Subprogram_Definition (Acc_Def);
10682 if No (Acc_Subprg) then
10683 return Designates_T (Subtype_Mark (Acc_Def));
10686 -- Component is an access_to_subprogram: examine its formals,
10687 -- and result definition in the case of an access_to_function.
10689 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10690 while Present (Param_Spec) loop
10691 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10692 and then Mentions_T (Parameter_Type (Param_Spec))
10696 elsif Designates_T (Parameter_Type (Param_Spec)) then
10703 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10704 if Nkind (Result_Definition (Acc_Subprg)) =
10705 N_Access_Definition
10707 return Mentions_T (Result_Definition (Acc_Subprg));
10709 return Designates_T (Result_Definition (Acc_Subprg));
10716 -- Start of processing for Check_Anonymous_Access_Components
10719 if No (Comp_List) then
10723 Comp := First (Component_Items (Comp_List));
10724 while Present (Comp) loop
10725 if Nkind (Comp) = N_Component_Declaration
10727 (Access_Definition (Component_Definition (Comp)))
10729 Mentions_T (Access_Definition (Component_Definition (Comp)))
10731 Comp_Def := Component_Definition (Comp);
10733 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10735 Build_Incomplete_Type_Declaration;
10736 Anon_Access := Make_Temporary (Loc, 'S');
10738 -- Create a declaration for the anonymous access type: either
10739 -- an access_to_object or an access_to_subprogram.
10741 if Present (Acc_Def) then
10742 if Nkind (Acc_Def) = N_Access_Function_Definition then
10744 Make_Access_Function_Definition (Loc,
10745 Parameter_Specifications =>
10746 Parameter_Specifications (Acc_Def),
10747 Result_Definition => Result_Definition (Acc_Def));
10750 Make_Access_Procedure_Definition (Loc,
10751 Parameter_Specifications =>
10752 Parameter_Specifications (Acc_Def));
10757 Make_Access_To_Object_Definition (Loc,
10758 Subtype_Indication =>
10760 (Subtype_Mark (Access_Definition (Comp_Def))));
10762 Set_Constant_Present
10763 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10765 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10768 Set_Null_Exclusion_Present
10770 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10773 Make_Full_Type_Declaration (Loc,
10774 Defining_Identifier => Anon_Access,
10775 Type_Definition => Type_Def);
10777 Insert_Before (Typ_Decl, Decl);
10780 -- If an access to subprogram, create the extra formals
10782 if Present (Acc_Def) then
10783 Create_Extra_Formals (Designated_Type (Anon_Access));
10785 -- If an access to object, preserve entity of designated type,
10786 -- for ASIS use, before rewriting the component definition.
10793 Desig := Entity (Subtype_Indication (Type_Def));
10795 -- If the access definition is to the current record,
10796 -- the visible entity at this point is an incomplete
10797 -- type. Retrieve the full view to simplify ASIS queries
10799 if Ekind (Desig) = E_Incomplete_Type then
10800 Desig := Full_View (Desig);
10804 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10809 Make_Component_Definition (Loc,
10810 Subtype_Indication =>
10811 New_Occurrence_Of (Anon_Access, Loc)));
10813 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10814 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10816 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10819 Set_Is_Local_Anonymous_Access (Anon_Access);
10825 if Present (Variant_Part (Comp_List)) then
10829 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10830 while Present (V) loop
10831 Check_Anonymous_Access_Components
10832 (Typ_Decl, Typ, Prev, Component_List (V));
10833 Next_Non_Pragma (V);
10837 end Check_Anonymous_Access_Components;
10839 ----------------------
10840 -- Check_Completion --
10841 ----------------------
10843 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10846 procedure Post_Error;
10847 -- Post error message for lack of completion for entity E
10853 procedure Post_Error is
10854 procedure Missing_Body;
10855 -- Output missing body message
10861 procedure Missing_Body is
10863 -- Spec is in same unit, so we can post on spec
10865 if In_Same_Source_Unit (Body_Id, E) then
10866 Error_Msg_N ("missing body for &", E);
10868 -- Spec is in a separate unit, so we have to post on the body
10871 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10875 -- Start of processing for Post_Error
10878 if not Comes_From_Source (E) then
10879 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10881 -- It may be an anonymous protected type created for a
10882 -- single variable. Post error on variable, if present.
10888 Var := First_Entity (Current_Scope);
10889 while Present (Var) loop
10890 exit when Etype (Var) = E
10891 and then Comes_From_Source (Var);
10896 if Present (Var) then
10903 -- If a generated entity has no completion, then either previous
10904 -- semantic errors have disabled the expansion phase, or else we had
10905 -- missing subunits, or else we are compiling without expansion,
10906 -- or else something is very wrong.
10908 if not Comes_From_Source (E) then
10910 (Serious_Errors_Detected > 0
10911 or else Configurable_Run_Time_Violations > 0
10912 or else Subunits_Missing
10913 or else not Expander_Active);
10916 -- Here for source entity
10919 -- Here if no body to post the error message, so we post the error
10920 -- on the declaration that has no completion. This is not really
10921 -- the right place to post it, think about this later ???
10923 if No (Body_Id) then
10924 if Is_Type (E) then
10926 ("missing full declaration for }", Parent (E), E);
10928 Error_Msg_NE ("missing body for &", Parent (E), E);
10931 -- Package body has no completion for a declaration that appears
10932 -- in the corresponding spec. Post error on the body, with a
10933 -- reference to the non-completed declaration.
10936 Error_Msg_Sloc := Sloc (E);
10938 if Is_Type (E) then
10939 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10941 elsif Is_Overloadable (E)
10942 and then Current_Entity_In_Scope (E) /= E
10944 -- It may be that the completion is mistyped and appears as
10945 -- a distinct overloading of the entity.
10948 Candidate : constant Entity_Id :=
10949 Current_Entity_In_Scope (E);
10950 Decl : constant Node_Id :=
10951 Unit_Declaration_Node (Candidate);
10954 if Is_Overloadable (Candidate)
10955 and then Ekind (Candidate) = Ekind (E)
10956 and then Nkind (Decl) = N_Subprogram_Body
10957 and then Acts_As_Spec (Decl)
10959 Check_Type_Conformant (Candidate, E);
10975 Pack_Id : constant Entity_Id := Current_Scope;
10977 -- Start of processing for Check_Completion
10980 E := First_Entity (Pack_Id);
10981 while Present (E) loop
10982 if Is_Intrinsic_Subprogram (E) then
10985 -- The following situation requires special handling: a child unit
10986 -- that appears in the context clause of the body of its parent:
10988 -- procedure Parent.Child (...);
10990 -- with Parent.Child;
10991 -- package body Parent is
10993 -- Here Parent.Child appears as a local entity, but should not be
10994 -- flagged as requiring completion, because it is a compilation
10997 -- Ignore missing completion for a subprogram that does not come from
10998 -- source (including the _Call primitive operation of RAS types,
10999 -- which has to have the flag Comes_From_Source for other purposes):
11000 -- we assume that the expander will provide the missing completion.
11001 -- In case of previous errors, other expansion actions that provide
11002 -- bodies for null procedures with not be invoked, so inhibit message
11005 -- Note that E_Operator is not in the list that follows, because
11006 -- this kind is reserved for predefined operators, that are
11007 -- intrinsic and do not need completion.
11009 elsif Ekind_In (E, E_Function,
11011 E_Generic_Function,
11012 E_Generic_Procedure)
11014 if Has_Completion (E) then
11017 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
11020 elsif Is_Subprogram (E)
11021 and then (not Comes_From_Source (E)
11022 or else Chars (E) = Name_uCall)
11027 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
11031 elsif Nkind (Parent (E)) = N_Procedure_Specification
11032 and then Null_Present (Parent (E))
11033 and then Serious_Errors_Detected > 0
11041 elsif Is_Entry (E) then
11042 if not Has_Completion (E) and then
11043 (Ekind (Scope (E)) = E_Protected_Object
11044 or else Ekind (Scope (E)) = E_Protected_Type)
11049 elsif Is_Package_Or_Generic_Package (E) then
11050 if Unit_Requires_Body (E) then
11051 if not Has_Completion (E)
11052 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
11058 elsif not Is_Child_Unit (E) then
11059 May_Need_Implicit_Body (E);
11062 -- A formal incomplete type (Ada 2012) does not require a completion;
11063 -- other incomplete type declarations do.
11065 elsif Ekind (E) = E_Incomplete_Type
11066 and then No (Underlying_Type (E))
11067 and then not Is_Generic_Type (E)
11071 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
11072 and then not Has_Completion (E)
11076 -- A single task declared in the current scope is a constant, verify
11077 -- that the body of its anonymous type is in the same scope. If the
11078 -- task is defined elsewhere, this may be a renaming declaration for
11079 -- which no completion is needed.
11081 elsif Ekind (E) = E_Constant
11082 and then Ekind (Etype (E)) = E_Task_Type
11083 and then not Has_Completion (Etype (E))
11084 and then Scope (Etype (E)) = Current_Scope
11088 elsif Ekind (E) = E_Protected_Object
11089 and then not Has_Completion (Etype (E))
11093 elsif Ekind (E) = E_Record_Type then
11094 if Is_Tagged_Type (E) then
11095 Check_Abstract_Overriding (E);
11096 Check_Conventions (E);
11099 Check_Aliased_Component_Types (E);
11101 elsif Ekind (E) = E_Array_Type then
11102 Check_Aliased_Component_Types (E);
11108 end Check_Completion;
11110 ------------------------------------
11111 -- Check_CPP_Type_Has_No_Defaults --
11112 ------------------------------------
11114 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11115 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11120 -- Obtain the component list
11122 if Nkind (Tdef) = N_Record_Definition then
11123 Clist := Component_List (Tdef);
11124 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11125 Clist := Component_List (Record_Extension_Part (Tdef));
11128 -- Check all components to ensure no default expressions
11130 if Present (Clist) then
11131 Comp := First (Component_Items (Clist));
11132 while Present (Comp) loop
11133 if Present (Expression (Comp)) then
11135 ("component of imported 'C'P'P type cannot have "
11136 & "default expression", Expression (Comp));
11142 end Check_CPP_Type_Has_No_Defaults;
11144 ----------------------------
11145 -- Check_Delta_Expression --
11146 ----------------------------
11148 procedure Check_Delta_Expression (E : Node_Id) is
11150 if not (Is_Real_Type (Etype (E))) then
11151 Wrong_Type (E, Any_Real);
11153 elsif not Is_OK_Static_Expression (E) then
11154 Flag_Non_Static_Expr
11155 ("non-static expression used for delta value!", E);
11157 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11158 Error_Msg_N ("delta expression must be positive", E);
11164 -- If any of above errors occurred, then replace the incorrect
11165 -- expression by the real 0.1, which should prevent further errors.
11168 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11169 Analyze_And_Resolve (E, Standard_Float);
11170 end Check_Delta_Expression;
11172 -----------------------------
11173 -- Check_Digits_Expression --
11174 -----------------------------
11176 procedure Check_Digits_Expression (E : Node_Id) is
11178 if not (Is_Integer_Type (Etype (E))) then
11179 Wrong_Type (E, Any_Integer);
11181 elsif not Is_OK_Static_Expression (E) then
11182 Flag_Non_Static_Expr
11183 ("non-static expression used for digits value!", E);
11185 elsif Expr_Value (E) <= 0 then
11186 Error_Msg_N ("digits value must be greater than zero", E);
11192 -- If any of above errors occurred, then replace the incorrect
11193 -- expression by the integer 1, which should prevent further errors.
11195 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11196 Analyze_And_Resolve (E, Standard_Integer);
11198 end Check_Digits_Expression;
11200 --------------------------
11201 -- Check_Initialization --
11202 --------------------------
11204 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11206 -- Special processing for limited types
11208 if Is_Limited_Type (T)
11209 and then not In_Instance
11210 and then not In_Inlined_Body
11212 if not OK_For_Limited_Init (T, Exp) then
11214 -- In GNAT mode, this is just a warning, to allow it to be evilly
11215 -- turned off. Otherwise it is a real error.
11219 ("??cannot initialize entities of limited type!", Exp);
11221 elsif Ada_Version < Ada_2005 then
11223 -- The side effect removal machinery may generate illegal Ada
11224 -- code to avoid the usage of access types and 'reference in
11225 -- SPARK mode. Since this is legal code with respect to theorem
11226 -- proving, do not emit the error.
11229 and then Nkind (Exp) = N_Function_Call
11230 and then Nkind (Parent (Exp)) = N_Object_Declaration
11231 and then not Comes_From_Source
11232 (Defining_Identifier (Parent (Exp)))
11238 ("cannot initialize entities of limited type", Exp);
11239 Explain_Limited_Type (T, Exp);
11243 -- Specialize error message according to kind of illegal
11244 -- initial expression.
11246 if Nkind (Exp) = N_Type_Conversion
11247 and then Nkind (Expression (Exp)) = N_Function_Call
11250 ("illegal context for call"
11251 & " to function with limited result", Exp);
11255 ("initialization of limited object requires aggregate "
11256 & "or function call", Exp);
11262 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11263 -- set unless we can be sure that no range check is required.
11265 if (GNATprove_Mode or not Expander_Active)
11266 and then Is_Scalar_Type (T)
11267 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11269 Set_Do_Range_Check (Exp);
11271 end Check_Initialization;
11273 ----------------------
11274 -- Check_Interfaces --
11275 ----------------------
11277 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11278 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11281 Iface_Def : Node_Id;
11282 Iface_Typ : Entity_Id;
11283 Parent_Node : Node_Id;
11285 Is_Task : Boolean := False;
11286 -- Set True if parent type or any progenitor is a task interface
11288 Is_Protected : Boolean := False;
11289 -- Set True if parent type or any progenitor is a protected interface
11291 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11292 -- Check that a progenitor is compatible with declaration. If an error
11293 -- message is output, it is posted on Error_Node.
11299 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11300 Iface_Id : constant Entity_Id :=
11301 Defining_Identifier (Parent (Iface_Def));
11302 Type_Def : Node_Id;
11305 if Nkind (N) = N_Private_Extension_Declaration then
11308 Type_Def := Type_Definition (N);
11311 if Is_Task_Interface (Iface_Id) then
11314 elsif Is_Protected_Interface (Iface_Id) then
11315 Is_Protected := True;
11318 if Is_Synchronized_Interface (Iface_Id) then
11320 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11321 -- extension derived from a synchronized interface must explicitly
11322 -- be declared synchronized, because the full view will be a
11323 -- synchronized type.
11325 if Nkind (N) = N_Private_Extension_Declaration then
11326 if not Synchronized_Present (N) then
11328 ("private extension of& must be explicitly synchronized",
11332 -- However, by 3.9.4(16/2), a full type that is a record extension
11333 -- is never allowed to derive from a synchronized interface (note
11334 -- that interfaces must be excluded from this check, because those
11335 -- are represented by derived type definitions in some cases).
11337 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11338 and then not Interface_Present (Type_Definition (N))
11340 Error_Msg_N ("record extension cannot derive from synchronized "
11341 & "interface", Error_Node);
11345 -- Check that the characteristics of the progenitor are compatible
11346 -- with the explicit qualifier in the declaration.
11347 -- The check only applies to qualifiers that come from source.
11348 -- Limited_Present also appears in the declaration of corresponding
11349 -- records, and the check does not apply to them.
11351 if Limited_Present (Type_Def)
11353 Is_Concurrent_Record_Type (Defining_Identifier (N))
11355 if Is_Limited_Interface (Parent_Type)
11356 and then not Is_Limited_Interface (Iface_Id)
11359 ("progenitor & must be limited interface",
11360 Error_Node, Iface_Id);
11363 (Task_Present (Iface_Def)
11364 or else Protected_Present (Iface_Def)
11365 or else Synchronized_Present (Iface_Def))
11366 and then Nkind (N) /= N_Private_Extension_Declaration
11367 and then not Error_Posted (N)
11370 ("progenitor & must be limited interface",
11371 Error_Node, Iface_Id);
11374 -- Protected interfaces can only inherit from limited, synchronized
11375 -- or protected interfaces.
11377 elsif Nkind (N) = N_Full_Type_Declaration
11378 and then Protected_Present (Type_Def)
11380 if Limited_Present (Iface_Def)
11381 or else Synchronized_Present (Iface_Def)
11382 or else Protected_Present (Iface_Def)
11386 elsif Task_Present (Iface_Def) then
11387 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11388 & "from task interface", Error_Node);
11391 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11392 & "from non-limited interface", Error_Node);
11395 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11396 -- limited and synchronized.
11398 elsif Synchronized_Present (Type_Def) then
11399 if Limited_Present (Iface_Def)
11400 or else Synchronized_Present (Iface_Def)
11404 elsif Protected_Present (Iface_Def)
11405 and then Nkind (N) /= N_Private_Extension_Declaration
11407 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11408 & "from protected interface", Error_Node);
11410 elsif Task_Present (Iface_Def)
11411 and then Nkind (N) /= N_Private_Extension_Declaration
11413 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11414 & "from task interface", Error_Node);
11416 elsif not Is_Limited_Interface (Iface_Id) then
11417 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11418 & "from non-limited interface", Error_Node);
11421 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11422 -- synchronized or task interfaces.
11424 elsif Nkind (N) = N_Full_Type_Declaration
11425 and then Task_Present (Type_Def)
11427 if Limited_Present (Iface_Def)
11428 or else Synchronized_Present (Iface_Def)
11429 or else Task_Present (Iface_Def)
11433 elsif Protected_Present (Iface_Def) then
11434 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11435 & "protected interface", Error_Node);
11438 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11439 & "non-limited interface", Error_Node);
11444 -- Start of processing for Check_Interfaces
11447 if Is_Interface (Parent_Type) then
11448 if Is_Task_Interface (Parent_Type) then
11451 elsif Is_Protected_Interface (Parent_Type) then
11452 Is_Protected := True;
11456 if Nkind (N) = N_Private_Extension_Declaration then
11458 -- Check that progenitors are compatible with declaration
11460 Iface := First (Interface_List (Def));
11461 while Present (Iface) loop
11462 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11464 Parent_Node := Parent (Base_Type (Iface_Typ));
11465 Iface_Def := Type_Definition (Parent_Node);
11467 if not Is_Interface (Iface_Typ) then
11468 Diagnose_Interface (Iface, Iface_Typ);
11470 Check_Ifaces (Iface_Def, Iface);
11476 if Is_Task and Is_Protected then
11478 ("type cannot derive from task and protected interface", N);
11484 -- Full type declaration of derived type.
11485 -- Check compatibility with parent if it is interface type
11487 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11488 and then Is_Interface (Parent_Type)
11490 Parent_Node := Parent (Parent_Type);
11492 -- More detailed checks for interface varieties
11495 (Iface_Def => Type_Definition (Parent_Node),
11496 Error_Node => Subtype_Indication (Type_Definition (N)));
11499 Iface := First (Interface_List (Def));
11500 while Present (Iface) loop
11501 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11503 Parent_Node := Parent (Base_Type (Iface_Typ));
11504 Iface_Def := Type_Definition (Parent_Node);
11506 if not Is_Interface (Iface_Typ) then
11507 Diagnose_Interface (Iface, Iface_Typ);
11510 -- "The declaration of a specific descendant of an interface
11511 -- type freezes the interface type" RM 13.14
11513 Freeze_Before (N, Iface_Typ);
11514 Check_Ifaces (Iface_Def, Error_Node => Iface);
11520 if Is_Task and Is_Protected then
11522 ("type cannot derive from task and protected interface", N);
11524 end Check_Interfaces;
11526 ------------------------------------
11527 -- Check_Or_Process_Discriminants --
11528 ------------------------------------
11530 -- If an incomplete or private type declaration was already given for the
11531 -- type, the discriminants may have already been processed if they were
11532 -- present on the incomplete declaration. In this case a full conformance
11533 -- check has been performed in Find_Type_Name, and we then recheck here
11534 -- some properties that can't be checked on the partial view alone.
11535 -- Otherwise we call Process_Discriminants.
11537 procedure Check_Or_Process_Discriminants
11540 Prev : Entity_Id := Empty)
11543 if Has_Discriminants (T) then
11545 -- Discriminants are already set on T if they were already present
11546 -- on the partial view. Make them visible to component declarations.
11550 -- Discriminant on T (full view) referencing expr on partial view
11552 Prev_D : Entity_Id;
11553 -- Entity of corresponding discriminant on partial view
11556 -- Discriminant specification for full view, expression is
11557 -- the syntactic copy on full view (which has been checked for
11558 -- conformance with partial view), only used here to post error
11562 D := First_Discriminant (T);
11563 New_D := First (Discriminant_Specifications (N));
11564 while Present (D) loop
11565 Prev_D := Current_Entity (D);
11566 Set_Current_Entity (D);
11567 Set_Is_Immediately_Visible (D);
11568 Set_Homonym (D, Prev_D);
11570 -- Handle the case where there is an untagged partial view and
11571 -- the full view is tagged: must disallow discriminants with
11572 -- defaults, unless compiling for Ada 2012, which allows a
11573 -- limited tagged type to have defaulted discriminants (see
11574 -- AI05-0214). However, suppress error here if it was already
11575 -- reported on the default expression of the partial view.
11577 if Is_Tagged_Type (T)
11578 and then Present (Expression (Parent (D)))
11579 and then (not Is_Limited_Type (Current_Scope)
11580 or else Ada_Version < Ada_2012)
11581 and then not Error_Posted (Expression (Parent (D)))
11583 if Ada_Version >= Ada_2012 then
11585 ("discriminants of nonlimited tagged type cannot have "
11587 Expression (New_D));
11590 ("discriminants of tagged type cannot have defaults",
11591 Expression (New_D));
11595 -- Ada 2005 (AI-230): Access discriminant allowed in
11596 -- non-limited record types.
11598 if Ada_Version < Ada_2005 then
11600 -- This restriction gets applied to the full type here. It
11601 -- has already been applied earlier to the partial view.
11603 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11606 Next_Discriminant (D);
11611 elsif Present (Discriminant_Specifications (N)) then
11612 Process_Discriminants (N, Prev);
11614 end Check_Or_Process_Discriminants;
11616 ----------------------
11617 -- Check_Real_Bound --
11618 ----------------------
11620 procedure Check_Real_Bound (Bound : Node_Id) is
11622 if not Is_Real_Type (Etype (Bound)) then
11624 ("bound in real type definition must be of real type", Bound);
11626 elsif not Is_OK_Static_Expression (Bound) then
11627 Flag_Non_Static_Expr
11628 ("non-static expression used for real type bound!", Bound);
11635 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11637 Resolve (Bound, Standard_Float);
11638 end Check_Real_Bound;
11640 ------------------------------
11641 -- Complete_Private_Subtype --
11642 ------------------------------
11644 procedure Complete_Private_Subtype
11647 Full_Base : Entity_Id;
11648 Related_Nod : Node_Id)
11650 Save_Next_Entity : Entity_Id;
11651 Save_Homonym : Entity_Id;
11654 -- Set semantic attributes for (implicit) private subtype completion.
11655 -- If the full type has no discriminants, then it is a copy of the
11656 -- full view of the base. Otherwise, it is a subtype of the base with
11657 -- a possible discriminant constraint. Save and restore the original
11658 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11659 -- not corrupt the entity chain.
11661 -- Note that the type of the full view is the same entity as the type
11662 -- of the partial view. In this fashion, the subtype has access to the
11663 -- correct view of the parent.
11665 Save_Next_Entity := Next_Entity (Full);
11666 Save_Homonym := Homonym (Priv);
11668 case Ekind (Full_Base) is
11669 when E_Record_Type |
11675 Copy_Node (Priv, Full);
11677 Set_Has_Discriminants
11678 (Full, Has_Discriminants (Full_Base));
11679 Set_Has_Unknown_Discriminants
11680 (Full, Has_Unknown_Discriminants (Full_Base));
11681 Set_First_Entity (Full, First_Entity (Full_Base));
11682 Set_Last_Entity (Full, Last_Entity (Full_Base));
11684 -- If the underlying base type is constrained, we know that the
11685 -- full view of the subtype is constrained as well (the converse
11686 -- is not necessarily true).
11688 if Is_Constrained (Full_Base) then
11689 Set_Is_Constrained (Full);
11693 Copy_Node (Full_Base, Full);
11695 Set_Chars (Full, Chars (Priv));
11696 Conditional_Delay (Full, Priv);
11697 Set_Sloc (Full, Sloc (Priv));
11700 Set_Next_Entity (Full, Save_Next_Entity);
11701 Set_Homonym (Full, Save_Homonym);
11702 Set_Associated_Node_For_Itype (Full, Related_Nod);
11704 -- Set common attributes for all subtypes: kind, convention, etc.
11706 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11707 Set_Convention (Full, Convention (Full_Base));
11709 -- The Etype of the full view is inconsistent. Gigi needs to see the
11710 -- structural full view, which is what the current scheme gives: the
11711 -- Etype of the full view is the etype of the full base. However, if the
11712 -- full base is a derived type, the full view then looks like a subtype
11713 -- of the parent, not a subtype of the full base. If instead we write:
11715 -- Set_Etype (Full, Full_Base);
11717 -- then we get inconsistencies in the front-end (confusion between
11718 -- views). Several outstanding bugs are related to this ???
11720 Set_Is_First_Subtype (Full, False);
11721 Set_Scope (Full, Scope (Priv));
11722 Set_Size_Info (Full, Full_Base);
11723 Set_RM_Size (Full, RM_Size (Full_Base));
11724 Set_Is_Itype (Full);
11726 -- A subtype of a private-type-without-discriminants, whose full-view
11727 -- has discriminants with default expressions, is not constrained.
11729 if not Has_Discriminants (Priv) then
11730 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11732 if Has_Discriminants (Full_Base) then
11733 Set_Discriminant_Constraint
11734 (Full, Discriminant_Constraint (Full_Base));
11736 -- The partial view may have been indefinite, the full view
11739 Set_Has_Unknown_Discriminants
11740 (Full, Has_Unknown_Discriminants (Full_Base));
11744 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11745 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11747 -- Freeze the private subtype entity if its parent is delayed, and not
11748 -- already frozen. We skip this processing if the type is an anonymous
11749 -- subtype of a record component, or is the corresponding record of a
11750 -- protected type, since these are processed when the enclosing type
11753 if not Is_Type (Scope (Full)) then
11754 Set_Has_Delayed_Freeze (Full,
11755 Has_Delayed_Freeze (Full_Base)
11756 and then (not Is_Frozen (Full_Base)));
11759 Set_Freeze_Node (Full, Empty);
11760 Set_Is_Frozen (Full, False);
11761 Set_Full_View (Priv, Full);
11763 if Has_Discriminants (Full) then
11764 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11765 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11767 if Has_Unknown_Discriminants (Full) then
11768 Set_Discriminant_Constraint (Full, No_Elist);
11772 if Ekind (Full_Base) = E_Record_Type
11773 and then Has_Discriminants (Full_Base)
11774 and then Has_Discriminants (Priv) -- might not, if errors
11775 and then not Has_Unknown_Discriminants (Priv)
11776 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11778 Create_Constrained_Components
11779 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11781 -- If the full base is itself derived from private, build a congruent
11782 -- subtype of its underlying type, for use by the back end. For a
11783 -- constrained record component, the declaration cannot be placed on
11784 -- the component list, but it must nevertheless be built an analyzed, to
11785 -- supply enough information for Gigi to compute the size of component.
11787 elsif Ekind (Full_Base) in Private_Kind
11788 and then Is_Derived_Type (Full_Base)
11789 and then Has_Discriminants (Full_Base)
11790 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11792 if not Is_Itype (Priv)
11794 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11796 Build_Underlying_Full_View
11797 (Parent (Priv), Full, Etype (Full_Base));
11799 elsif Nkind (Related_Nod) = N_Component_Declaration then
11800 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11803 elsif Is_Record_Type (Full_Base) then
11805 -- Show Full is simply a renaming of Full_Base
11807 Set_Cloned_Subtype (Full, Full_Base);
11810 -- It is unsafe to share the bounds of a scalar type, because the Itype
11811 -- is elaborated on demand, and if a bound is non-static then different
11812 -- orders of elaboration in different units will lead to different
11813 -- external symbols.
11815 if Is_Scalar_Type (Full_Base) then
11816 Set_Scalar_Range (Full,
11817 Make_Range (Sloc (Related_Nod),
11819 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11821 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11823 -- This completion inherits the bounds of the full parent, but if
11824 -- the parent is an unconstrained floating point type, so is the
11827 if Is_Floating_Point_Type (Full_Base) then
11828 Set_Includes_Infinities
11829 (Scalar_Range (Full), Has_Infinities (Full_Base));
11833 -- ??? It seems that a lot of fields are missing that should be copied
11834 -- from Full_Base to Full. Here are some that are introduced in a
11835 -- non-disruptive way but a cleanup is necessary.
11837 if Is_Tagged_Type (Full_Base) then
11838 Set_Is_Tagged_Type (Full);
11839 Set_Direct_Primitive_Operations
11840 (Full, Direct_Primitive_Operations (Full_Base));
11841 Set_No_Tagged_Streams_Pragma
11842 (Full, No_Tagged_Streams_Pragma (Full_Base));
11844 -- Inherit class_wide type of full_base in case the partial view was
11845 -- not tagged. Otherwise it has already been created when the private
11846 -- subtype was analyzed.
11848 if No (Class_Wide_Type (Full)) then
11849 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11852 -- If this is a subtype of a protected or task type, constrain its
11853 -- corresponding record, unless this is a subtype without constraints,
11854 -- i.e. a simple renaming as with an actual subtype in an instance.
11856 elsif Is_Concurrent_Type (Full_Base) then
11857 if Has_Discriminants (Full)
11858 and then Present (Corresponding_Record_Type (Full_Base))
11860 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11862 Set_Corresponding_Record_Type (Full,
11863 Constrain_Corresponding_Record
11864 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11867 Set_Corresponding_Record_Type (Full,
11868 Corresponding_Record_Type (Full_Base));
11872 -- Link rep item chain, and also setting of Has_Predicates from private
11873 -- subtype to full subtype, since we will need these on the full subtype
11874 -- to create the predicate function. Note that the full subtype may
11875 -- already have rep items, inherited from the full view of the base
11876 -- type, so we must be sure not to overwrite these entries.
11881 Next_Item : Node_Id;
11884 Item := First_Rep_Item (Full);
11886 -- If no existing rep items on full type, we can just link directly
11887 -- to the list of items on the private type, if any exist.. Same if
11888 -- the rep items are only those inherited from the base
11891 or else Nkind (Item) /= N_Aspect_Specification
11892 or else Entity (Item) = Full_Base)
11893 and then Present (First_Rep_Item (Priv))
11895 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11897 -- Otherwise, search to the end of items currently linked to the full
11898 -- subtype and append the private items to the end. However, if Priv
11899 -- and Full already have the same list of rep items, then the append
11900 -- is not done, as that would create a circularity.
11902 elsif Item /= First_Rep_Item (Priv) then
11905 Next_Item := Next_Rep_Item (Item);
11906 exit when No (Next_Item);
11909 -- If the private view has aspect specifications, the full view
11910 -- inherits them. Since these aspects may already have been
11911 -- attached to the full view during derivation, do not append
11912 -- them if already present.
11914 if Item = First_Rep_Item (Priv) then
11920 -- And link the private type items at the end of the chain
11923 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11928 -- Make sure Has_Predicates is set on full type if it is set on the
11929 -- private type. Note that it may already be set on the full type and
11930 -- if so, we don't want to unset it. Similarly, propagate information
11931 -- about delayed aspects, because the corresponding pragmas must be
11932 -- analyzed when one of the views is frozen. This last step is needed
11933 -- in particular when the full type is a scalar type for which an
11934 -- anonymous base type is constructed.
11936 -- The predicate functions are generated either at the freeze point
11937 -- of the type or at the end of the visible part, and we must avoid
11938 -- generating them twice.
11940 if Has_Predicates (Priv) then
11941 Set_Has_Predicates (Full);
11943 if Present (Predicate_Function (Priv))
11944 and then No (Predicate_Function (Full))
11946 Set_Predicate_Function (Full, Predicate_Function (Priv));
11950 if Has_Delayed_Aspects (Priv) then
11951 Set_Has_Delayed_Aspects (Full);
11953 end Complete_Private_Subtype;
11955 ----------------------------
11956 -- Constant_Redeclaration --
11957 ----------------------------
11959 procedure Constant_Redeclaration
11964 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11965 Obj_Def : constant Node_Id := Object_Definition (N);
11968 procedure Check_Possible_Deferred_Completion
11969 (Prev_Id : Entity_Id;
11970 Prev_Obj_Def : Node_Id;
11971 Curr_Obj_Def : Node_Id);
11972 -- Determine whether the two object definitions describe the partial
11973 -- and the full view of a constrained deferred constant. Generate
11974 -- a subtype for the full view and verify that it statically matches
11975 -- the subtype of the partial view.
11977 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11978 -- If deferred constant is an access type initialized with an allocator,
11979 -- check whether there is an illegal recursion in the definition,
11980 -- through a default value of some record subcomponent. This is normally
11981 -- detected when generating init procs, but requires this additional
11982 -- mechanism when expansion is disabled.
11984 ----------------------------------------
11985 -- Check_Possible_Deferred_Completion --
11986 ----------------------------------------
11988 procedure Check_Possible_Deferred_Completion
11989 (Prev_Id : Entity_Id;
11990 Prev_Obj_Def : Node_Id;
11991 Curr_Obj_Def : Node_Id)
11994 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11995 and then Present (Constraint (Prev_Obj_Def))
11996 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11997 and then Present (Constraint (Curr_Obj_Def))
12000 Loc : constant Source_Ptr := Sloc (N);
12001 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
12002 Decl : constant Node_Id :=
12003 Make_Subtype_Declaration (Loc,
12004 Defining_Identifier => Def_Id,
12005 Subtype_Indication =>
12006 Relocate_Node (Curr_Obj_Def));
12009 Insert_Before_And_Analyze (N, Decl);
12010 Set_Etype (Id, Def_Id);
12012 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
12013 Error_Msg_Sloc := Sloc (Prev_Id);
12014 Error_Msg_N ("subtype does not statically match deferred "
12015 & "declaration #", N);
12019 end Check_Possible_Deferred_Completion;
12021 ---------------------------------
12022 -- Check_Recursive_Declaration --
12023 ---------------------------------
12025 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
12029 if Is_Record_Type (Typ) then
12030 Comp := First_Component (Typ);
12031 while Present (Comp) loop
12032 if Comes_From_Source (Comp) then
12033 if Present (Expression (Parent (Comp)))
12034 and then Is_Entity_Name (Expression (Parent (Comp)))
12035 and then Entity (Expression (Parent (Comp))) = Prev
12037 Error_Msg_Sloc := Sloc (Parent (Comp));
12039 ("illegal circularity with declaration for & #",
12043 elsif Is_Record_Type (Etype (Comp)) then
12044 Check_Recursive_Declaration (Etype (Comp));
12048 Next_Component (Comp);
12051 end Check_Recursive_Declaration;
12053 -- Start of processing for Constant_Redeclaration
12056 if Nkind (Parent (Prev)) = N_Object_Declaration then
12057 if Nkind (Object_Definition
12058 (Parent (Prev))) = N_Subtype_Indication
12060 -- Find type of new declaration. The constraints of the two
12061 -- views must match statically, but there is no point in
12062 -- creating an itype for the full view.
12064 if Nkind (Obj_Def) = N_Subtype_Indication then
12065 Find_Type (Subtype_Mark (Obj_Def));
12066 New_T := Entity (Subtype_Mark (Obj_Def));
12069 Find_Type (Obj_Def);
12070 New_T := Entity (Obj_Def);
12076 -- The full view may impose a constraint, even if the partial
12077 -- view does not, so construct the subtype.
12079 New_T := Find_Type_Of_Object (Obj_Def, N);
12084 -- Current declaration is illegal, diagnosed below in Enter_Name
12090 -- If previous full declaration or a renaming declaration exists, or if
12091 -- a homograph is present, let Enter_Name handle it, either with an
12092 -- error or with the removal of an overridden implicit subprogram.
12093 -- The previous one is a full declaration if it has an expression
12094 -- (which in the case of an aggregate is indicated by the Init flag).
12096 if Ekind (Prev) /= E_Constant
12097 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12098 or else Present (Expression (Parent (Prev)))
12099 or else Has_Init_Expression (Parent (Prev))
12100 or else Present (Full_View (Prev))
12104 -- Verify that types of both declarations match, or else that both types
12105 -- are anonymous access types whose designated subtypes statically match
12106 -- (as allowed in Ada 2005 by AI-385).
12108 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12110 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12111 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12112 or else Is_Access_Constant (Etype (New_T)) /=
12113 Is_Access_Constant (Etype (Prev))
12114 or else Can_Never_Be_Null (Etype (New_T)) /=
12115 Can_Never_Be_Null (Etype (Prev))
12116 or else Null_Exclusion_Present (Parent (Prev)) /=
12117 Null_Exclusion_Present (Parent (Id))
12118 or else not Subtypes_Statically_Match
12119 (Designated_Type (Etype (Prev)),
12120 Designated_Type (Etype (New_T))))
12122 Error_Msg_Sloc := Sloc (Prev);
12123 Error_Msg_N ("type does not match declaration#", N);
12124 Set_Full_View (Prev, Id);
12125 Set_Etype (Id, Any_Type);
12127 -- A deferred constant whose type is an anonymous array is always
12128 -- illegal (unless imported). A detailed error message might be
12129 -- helpful for Ada beginners.
12131 if Nkind (Object_Definition (Parent (Prev)))
12132 = N_Constrained_Array_Definition
12133 and then Nkind (Object_Definition (N))
12134 = N_Constrained_Array_Definition
12136 Error_Msg_N ("\each anonymous array is a distinct type", N);
12137 Error_Msg_N ("a deferred constant must have a named type",
12138 Object_Definition (Parent (Prev)));
12142 Null_Exclusion_Present (Parent (Prev))
12143 and then not Null_Exclusion_Present (N)
12145 Error_Msg_Sloc := Sloc (Prev);
12146 Error_Msg_N ("null-exclusion does not match declaration#", N);
12147 Set_Full_View (Prev, Id);
12148 Set_Etype (Id, Any_Type);
12150 -- If so, process the full constant declaration
12153 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12154 -- the deferred declaration is constrained, then the subtype defined
12155 -- by the subtype_indication in the full declaration shall match it
12158 Check_Possible_Deferred_Completion
12160 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12161 Curr_Obj_Def => Obj_Def);
12163 Set_Full_View (Prev, Id);
12164 Set_Is_Public (Id, Is_Public (Prev));
12165 Set_Is_Internal (Id);
12166 Append_Entity (Id, Current_Scope);
12168 -- Check ALIASED present if present before (RM 7.4(7))
12170 if Is_Aliased (Prev)
12171 and then not Aliased_Present (N)
12173 Error_Msg_Sloc := Sloc (Prev);
12174 Error_Msg_N ("ALIASED required (see declaration #)", N);
12177 -- Check that placement is in private part and that the incomplete
12178 -- declaration appeared in the visible part.
12180 if Ekind (Current_Scope) = E_Package
12181 and then not In_Private_Part (Current_Scope)
12183 Error_Msg_Sloc := Sloc (Prev);
12185 ("full constant for declaration # must be in private part", N);
12187 elsif Ekind (Current_Scope) = E_Package
12189 List_Containing (Parent (Prev)) /=
12190 Visible_Declarations (Package_Specification (Current_Scope))
12193 ("deferred constant must be declared in visible part",
12197 if Is_Access_Type (T)
12198 and then Nkind (Expression (N)) = N_Allocator
12200 Check_Recursive_Declaration (Designated_Type (T));
12203 -- A deferred constant is a visible entity. If type has invariants,
12204 -- verify that the initial value satisfies them.
12206 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12208 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12211 end Constant_Redeclaration;
12213 ----------------------
12214 -- Constrain_Access --
12215 ----------------------
12217 procedure Constrain_Access
12218 (Def_Id : in out Entity_Id;
12220 Related_Nod : Node_Id)
12222 T : constant Entity_Id := Entity (Subtype_Mark (S));
12223 Desig_Type : constant Entity_Id := Designated_Type (T);
12224 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12225 Constraint_OK : Boolean := True;
12228 if Is_Array_Type (Desig_Type) then
12229 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12231 elsif (Is_Record_Type (Desig_Type)
12232 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12233 and then not Is_Constrained (Desig_Type)
12235 -- ??? The following code is a temporary bypass to ignore a
12236 -- discriminant constraint on access type if it is constraining
12237 -- the current record. Avoid creating the implicit subtype of the
12238 -- record we are currently compiling since right now, we cannot
12239 -- handle these. For now, just return the access type itself.
12241 if Desig_Type = Current_Scope
12242 and then No (Def_Id)
12244 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12245 Def_Id := Entity (Subtype_Mark (S));
12247 -- This call added to ensure that the constraint is analyzed
12248 -- (needed for a B test). Note that we still return early from
12249 -- this procedure to avoid recursive processing. ???
12251 Constrain_Discriminated_Type
12252 (Desig_Subtype, S, Related_Nod, For_Access => True);
12256 -- Enforce rule that the constraint is illegal if there is an
12257 -- unconstrained view of the designated type. This means that the
12258 -- partial view (either a private type declaration or a derivation
12259 -- from a private type) has no discriminants. (Defect Report
12260 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12262 -- Rule updated for Ada 2005: The private type is said to have
12263 -- a constrained partial view, given that objects of the type
12264 -- can be declared. Furthermore, the rule applies to all access
12265 -- types, unlike the rule concerning default discriminants (see
12268 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12269 and then Has_Private_Declaration (Desig_Type)
12270 and then In_Open_Scopes (Scope (Desig_Type))
12271 and then Has_Discriminants (Desig_Type)
12274 Pack : constant Node_Id :=
12275 Unit_Declaration_Node (Scope (Desig_Type));
12280 if Nkind (Pack) = N_Package_Declaration then
12281 Decls := Visible_Declarations (Specification (Pack));
12282 Decl := First (Decls);
12283 while Present (Decl) loop
12284 if (Nkind (Decl) = N_Private_Type_Declaration
12285 and then Chars (Defining_Identifier (Decl)) =
12286 Chars (Desig_Type))
12289 (Nkind (Decl) = N_Full_Type_Declaration
12291 Chars (Defining_Identifier (Decl)) =
12293 and then Is_Derived_Type (Desig_Type)
12295 Has_Private_Declaration (Etype (Desig_Type)))
12297 if No (Discriminant_Specifications (Decl)) then
12299 ("cannot constrain access type if designated "
12300 & "type has constrained partial view", S);
12312 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12313 For_Access => True);
12315 elsif Is_Concurrent_Type (Desig_Type)
12316 and then not Is_Constrained (Desig_Type)
12318 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12321 Error_Msg_N ("invalid constraint on access type", S);
12323 -- We simply ignore an invalid constraint
12325 Desig_Subtype := Desig_Type;
12326 Constraint_OK := False;
12329 if No (Def_Id) then
12330 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12332 Set_Ekind (Def_Id, E_Access_Subtype);
12335 if Constraint_OK then
12336 Set_Etype (Def_Id, Base_Type (T));
12338 if Is_Private_Type (Desig_Type) then
12339 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12342 Set_Etype (Def_Id, Any_Type);
12345 Set_Size_Info (Def_Id, T);
12346 Set_Is_Constrained (Def_Id, Constraint_OK);
12347 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12348 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12349 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12351 Conditional_Delay (Def_Id, T);
12353 -- AI-363 : Subtypes of general access types whose designated types have
12354 -- default discriminants are disallowed. In instances, the rule has to
12355 -- be checked against the actual, of which T is the subtype. In a
12356 -- generic body, the rule is checked assuming that the actual type has
12357 -- defaulted discriminants.
12359 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12360 if Ekind (Base_Type (T)) = E_General_Access_Type
12361 and then Has_Defaulted_Discriminants (Desig_Type)
12363 if Ada_Version < Ada_2005 then
12365 ("access subtype of general access type would not " &
12366 "be allowed in Ada 2005?y?", S);
12369 ("access subtype of general access type not allowed", S);
12372 Error_Msg_N ("\discriminants have defaults", S);
12374 elsif Is_Access_Type (T)
12375 and then Is_Generic_Type (Desig_Type)
12376 and then Has_Discriminants (Desig_Type)
12377 and then In_Package_Body (Current_Scope)
12379 if Ada_Version < Ada_2005 then
12381 ("access subtype would not be allowed in generic body "
12382 & "in Ada 2005?y?", S);
12385 ("access subtype not allowed in generic body", S);
12389 ("\designated type is a discriminated formal", S);
12392 end Constrain_Access;
12394 ---------------------
12395 -- Constrain_Array --
12396 ---------------------
12398 procedure Constrain_Array
12399 (Def_Id : in out Entity_Id;
12401 Related_Nod : Node_Id;
12402 Related_Id : Entity_Id;
12403 Suffix : Character)
12405 C : constant Node_Id := Constraint (SI);
12406 Number_Of_Constraints : Nat := 0;
12409 Constraint_OK : Boolean := True;
12412 T := Entity (Subtype_Mark (SI));
12414 if Is_Access_Type (T) then
12415 T := Designated_Type (T);
12418 -- If an index constraint follows a subtype mark in a subtype indication
12419 -- then the type or subtype denoted by the subtype mark must not already
12420 -- impose an index constraint. The subtype mark must denote either an
12421 -- unconstrained array type or an access type whose designated type
12422 -- is such an array type... (RM 3.6.1)
12424 if Is_Constrained (T) then
12425 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12426 Constraint_OK := False;
12429 S := First (Constraints (C));
12430 while Present (S) loop
12431 Number_Of_Constraints := Number_Of_Constraints + 1;
12435 -- In either case, the index constraint must provide a discrete
12436 -- range for each index of the array type and the type of each
12437 -- discrete range must be the same as that of the corresponding
12438 -- index. (RM 3.6.1)
12440 if Number_Of_Constraints /= Number_Dimensions (T) then
12441 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12442 Constraint_OK := False;
12445 S := First (Constraints (C));
12446 Index := First_Index (T);
12449 -- Apply constraints to each index type
12451 for J in 1 .. Number_Of_Constraints loop
12452 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12460 if No (Def_Id) then
12462 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12463 Set_Parent (Def_Id, Related_Nod);
12466 Set_Ekind (Def_Id, E_Array_Subtype);
12469 Set_Size_Info (Def_Id, (T));
12470 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12471 Set_Etype (Def_Id, Base_Type (T));
12473 if Constraint_OK then
12474 Set_First_Index (Def_Id, First (Constraints (C)));
12476 Set_First_Index (Def_Id, First_Index (T));
12479 Set_Is_Constrained (Def_Id, True);
12480 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12481 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12483 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12484 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12486 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12487 -- We need to initialize the attribute because if Def_Id is previously
12488 -- analyzed through a limited_with clause, it will have the attributes
12489 -- of an incomplete type, one of which is an Elist that overlaps the
12490 -- Packed_Array_Impl_Type field.
12492 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12494 -- Build a freeze node if parent still needs one. Also make sure that
12495 -- the Depends_On_Private status is set because the subtype will need
12496 -- reprocessing at the time the base type does, and also we must set a
12497 -- conditional delay.
12499 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12500 Conditional_Delay (Def_Id, T);
12501 end Constrain_Array;
12503 ------------------------------
12504 -- Constrain_Component_Type --
12505 ------------------------------
12507 function Constrain_Component_Type
12509 Constrained_Typ : Entity_Id;
12510 Related_Node : Node_Id;
12512 Constraints : Elist_Id) return Entity_Id
12514 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12515 Compon_Type : constant Entity_Id := Etype (Comp);
12517 function Build_Constrained_Array_Type
12518 (Old_Type : Entity_Id) return Entity_Id;
12519 -- If Old_Type is an array type, one of whose indexes is constrained
12520 -- by a discriminant, build an Itype whose constraint replaces the
12521 -- discriminant with its value in the constraint.
12523 function Build_Constrained_Discriminated_Type
12524 (Old_Type : Entity_Id) return Entity_Id;
12525 -- Ditto for record components
12527 function Build_Constrained_Access_Type
12528 (Old_Type : Entity_Id) return Entity_Id;
12529 -- Ditto for access types. Makes use of previous two functions, to
12530 -- constrain designated type.
12532 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12533 -- T is an array or discriminated type, C is a list of constraints
12534 -- that apply to T. This routine builds the constrained subtype.
12536 function Is_Discriminant (Expr : Node_Id) return Boolean;
12537 -- Returns True if Expr is a discriminant
12539 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12540 -- Find the value of discriminant Discrim in Constraint
12542 -----------------------------------
12543 -- Build_Constrained_Access_Type --
12544 -----------------------------------
12546 function Build_Constrained_Access_Type
12547 (Old_Type : Entity_Id) return Entity_Id
12549 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12551 Desig_Subtype : Entity_Id;
12555 -- if the original access type was not embedded in the enclosing
12556 -- type definition, there is no need to produce a new access
12557 -- subtype. In fact every access type with an explicit constraint
12558 -- generates an itype whose scope is the enclosing record.
12560 if not Is_Type (Scope (Old_Type)) then
12563 elsif Is_Array_Type (Desig_Type) then
12564 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12566 elsif Has_Discriminants (Desig_Type) then
12568 -- This may be an access type to an enclosing record type for
12569 -- which we are constructing the constrained components. Return
12570 -- the enclosing record subtype. This is not always correct,
12571 -- but avoids infinite recursion. ???
12573 Desig_Subtype := Any_Type;
12575 for J in reverse 0 .. Scope_Stack.Last loop
12576 Scop := Scope_Stack.Table (J).Entity;
12579 and then Base_Type (Scop) = Base_Type (Desig_Type)
12581 Desig_Subtype := Scop;
12584 exit when not Is_Type (Scop);
12587 if Desig_Subtype = Any_Type then
12589 Build_Constrained_Discriminated_Type (Desig_Type);
12596 if Desig_Subtype /= Desig_Type then
12598 -- The Related_Node better be here or else we won't be able
12599 -- to attach new itypes to a node in the tree.
12601 pragma Assert (Present (Related_Node));
12603 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12605 Set_Etype (Itype, Base_Type (Old_Type));
12606 Set_Size_Info (Itype, (Old_Type));
12607 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12608 Set_Depends_On_Private (Itype, Has_Private_Component
12610 Set_Is_Access_Constant (Itype, Is_Access_Constant
12613 -- The new itype needs freezing when it depends on a not frozen
12614 -- type and the enclosing subtype needs freezing.
12616 if Has_Delayed_Freeze (Constrained_Typ)
12617 and then not Is_Frozen (Constrained_Typ)
12619 Conditional_Delay (Itype, Base_Type (Old_Type));
12627 end Build_Constrained_Access_Type;
12629 ----------------------------------
12630 -- Build_Constrained_Array_Type --
12631 ----------------------------------
12633 function Build_Constrained_Array_Type
12634 (Old_Type : Entity_Id) return Entity_Id
12638 Old_Index : Node_Id;
12639 Range_Node : Node_Id;
12640 Constr_List : List_Id;
12642 Need_To_Create_Itype : Boolean := False;
12645 Old_Index := First_Index (Old_Type);
12646 while Present (Old_Index) loop
12647 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12649 if Is_Discriminant (Lo_Expr)
12651 Is_Discriminant (Hi_Expr)
12653 Need_To_Create_Itype := True;
12656 Next_Index (Old_Index);
12659 if Need_To_Create_Itype then
12660 Constr_List := New_List;
12662 Old_Index := First_Index (Old_Type);
12663 while Present (Old_Index) loop
12664 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12666 if Is_Discriminant (Lo_Expr) then
12667 Lo_Expr := Get_Discr_Value (Lo_Expr);
12670 if Is_Discriminant (Hi_Expr) then
12671 Hi_Expr := Get_Discr_Value (Hi_Expr);
12676 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12678 Append (Range_Node, To => Constr_List);
12680 Next_Index (Old_Index);
12683 return Build_Subtype (Old_Type, Constr_List);
12688 end Build_Constrained_Array_Type;
12690 ------------------------------------------
12691 -- Build_Constrained_Discriminated_Type --
12692 ------------------------------------------
12694 function Build_Constrained_Discriminated_Type
12695 (Old_Type : Entity_Id) return Entity_Id
12698 Constr_List : List_Id;
12699 Old_Constraint : Elmt_Id;
12701 Need_To_Create_Itype : Boolean := False;
12704 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12705 while Present (Old_Constraint) loop
12706 Expr := Node (Old_Constraint);
12708 if Is_Discriminant (Expr) then
12709 Need_To_Create_Itype := True;
12712 Next_Elmt (Old_Constraint);
12715 if Need_To_Create_Itype then
12716 Constr_List := New_List;
12718 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12719 while Present (Old_Constraint) loop
12720 Expr := Node (Old_Constraint);
12722 if Is_Discriminant (Expr) then
12723 Expr := Get_Discr_Value (Expr);
12726 Append (New_Copy_Tree (Expr), To => Constr_List);
12728 Next_Elmt (Old_Constraint);
12731 return Build_Subtype (Old_Type, Constr_List);
12736 end Build_Constrained_Discriminated_Type;
12738 -------------------
12739 -- Build_Subtype --
12740 -------------------
12742 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12744 Subtyp_Decl : Node_Id;
12745 Def_Id : Entity_Id;
12746 Btyp : Entity_Id := Base_Type (T);
12749 -- The Related_Node better be here or else we won't be able to
12750 -- attach new itypes to a node in the tree.
12752 pragma Assert (Present (Related_Node));
12754 -- If the view of the component's type is incomplete or private
12755 -- with unknown discriminants, then the constraint must be applied
12756 -- to the full type.
12758 if Has_Unknown_Discriminants (Btyp)
12759 and then Present (Underlying_Type (Btyp))
12761 Btyp := Underlying_Type (Btyp);
12765 Make_Subtype_Indication (Loc,
12766 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12767 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12769 Def_Id := Create_Itype (Ekind (T), Related_Node);
12772 Make_Subtype_Declaration (Loc,
12773 Defining_Identifier => Def_Id,
12774 Subtype_Indication => Indic);
12776 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12778 -- Itypes must be analyzed with checks off (see package Itypes)
12780 Analyze (Subtyp_Decl, Suppress => All_Checks);
12785 ---------------------
12786 -- Get_Discr_Value --
12787 ---------------------
12789 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12794 -- The discriminant may be declared for the type, in which case we
12795 -- find it by iterating over the list of discriminants. If the
12796 -- discriminant is inherited from a parent type, it appears as the
12797 -- corresponding discriminant of the current type. This will be the
12798 -- case when constraining an inherited component whose constraint is
12799 -- given by a discriminant of the parent.
12801 D := First_Discriminant (Typ);
12802 E := First_Elmt (Constraints);
12804 while Present (D) loop
12805 if D = Entity (Discrim)
12806 or else D = CR_Discriminant (Entity (Discrim))
12807 or else Corresponding_Discriminant (D) = Entity (Discrim)
12812 Next_Discriminant (D);
12816 -- The Corresponding_Discriminant mechanism is incomplete, because
12817 -- the correspondence between new and old discriminants is not one
12818 -- to one: one new discriminant can constrain several old ones. In
12819 -- that case, scan sequentially the stored_constraint, the list of
12820 -- discriminants of the parents, and the constraints.
12822 -- Previous code checked for the present of the Stored_Constraint
12823 -- list for the derived type, but did not use it at all. Should it
12824 -- be present when the component is a discriminated task type?
12826 if Is_Derived_Type (Typ)
12827 and then Scope (Entity (Discrim)) = Etype (Typ)
12829 D := First_Discriminant (Etype (Typ));
12830 E := First_Elmt (Constraints);
12831 while Present (D) loop
12832 if D = Entity (Discrim) then
12836 Next_Discriminant (D);
12841 -- Something is wrong if we did not find the value
12843 raise Program_Error;
12844 end Get_Discr_Value;
12846 ---------------------
12847 -- Is_Discriminant --
12848 ---------------------
12850 function Is_Discriminant (Expr : Node_Id) return Boolean is
12851 Discrim_Scope : Entity_Id;
12854 if Denotes_Discriminant (Expr) then
12855 Discrim_Scope := Scope (Entity (Expr));
12857 -- Either we have a reference to one of Typ's discriminants,
12859 pragma Assert (Discrim_Scope = Typ
12861 -- or to the discriminants of the parent type, in the case
12862 -- of a derivation of a tagged type with variants.
12864 or else Discrim_Scope = Etype (Typ)
12865 or else Full_View (Discrim_Scope) = Etype (Typ)
12867 -- or same as above for the case where the discriminants
12868 -- were declared in Typ's private view.
12870 or else (Is_Private_Type (Discrim_Scope)
12871 and then Chars (Discrim_Scope) = Chars (Typ))
12873 -- or else we are deriving from the full view and the
12874 -- discriminant is declared in the private entity.
12876 or else (Is_Private_Type (Typ)
12877 and then Chars (Discrim_Scope) = Chars (Typ))
12879 -- Or we are constrained the corresponding record of a
12880 -- synchronized type that completes a private declaration.
12882 or else (Is_Concurrent_Record_Type (Typ)
12884 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12886 -- or we have a class-wide type, in which case make sure the
12887 -- discriminant found belongs to the root type.
12889 or else (Is_Class_Wide_Type (Typ)
12890 and then Etype (Typ) = Discrim_Scope));
12895 -- In all other cases we have something wrong
12898 end Is_Discriminant;
12900 -- Start of processing for Constrain_Component_Type
12903 if Nkind (Parent (Comp)) = N_Component_Declaration
12904 and then Comes_From_Source (Parent (Comp))
12905 and then Comes_From_Source
12906 (Subtype_Indication (Component_Definition (Parent (Comp))))
12909 (Subtype_Indication (Component_Definition (Parent (Comp))))
12911 return Compon_Type;
12913 elsif Is_Array_Type (Compon_Type) then
12914 return Build_Constrained_Array_Type (Compon_Type);
12916 elsif Has_Discriminants (Compon_Type) then
12917 return Build_Constrained_Discriminated_Type (Compon_Type);
12919 elsif Is_Access_Type (Compon_Type) then
12920 return Build_Constrained_Access_Type (Compon_Type);
12923 return Compon_Type;
12925 end Constrain_Component_Type;
12927 --------------------------
12928 -- Constrain_Concurrent --
12929 --------------------------
12931 -- For concurrent types, the associated record value type carries the same
12932 -- discriminants, so when we constrain a concurrent type, we must constrain
12933 -- the corresponding record type as well.
12935 procedure Constrain_Concurrent
12936 (Def_Id : in out Entity_Id;
12938 Related_Nod : Node_Id;
12939 Related_Id : Entity_Id;
12940 Suffix : Character)
12942 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12943 -- case of a private subtype (needed when only doing semantic analysis).
12945 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12949 if Is_Access_Type (T_Ent) then
12950 T_Ent := Designated_Type (T_Ent);
12953 T_Val := Corresponding_Record_Type (T_Ent);
12955 if Present (T_Val) then
12957 if No (Def_Id) then
12958 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12960 -- Elaborate itype now, as it may be used in a subsequent
12961 -- synchronized operation in another scope.
12963 if Nkind (Related_Nod) = N_Full_Type_Declaration then
12964 Build_Itype_Reference (Def_Id, Related_Nod);
12968 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12970 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12971 Set_Corresponding_Record_Type (Def_Id,
12972 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12975 -- If there is no associated record, expansion is disabled and this
12976 -- is a generic context. Create a subtype in any case, so that
12977 -- semantic analysis can proceed.
12979 if No (Def_Id) then
12980 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12983 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12985 end Constrain_Concurrent;
12987 ------------------------------------
12988 -- Constrain_Corresponding_Record --
12989 ------------------------------------
12991 function Constrain_Corresponding_Record
12992 (Prot_Subt : Entity_Id;
12993 Corr_Rec : Entity_Id;
12994 Related_Nod : Node_Id) return Entity_Id
12996 T_Sub : constant Entity_Id :=
12997 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
13000 Set_Etype (T_Sub, Corr_Rec);
13001 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
13002 Set_Is_Constrained (T_Sub, True);
13003 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
13004 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
13006 if Has_Discriminants (Prot_Subt) then -- False only if errors.
13007 Set_Discriminant_Constraint
13008 (T_Sub, Discriminant_Constraint (Prot_Subt));
13009 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
13010 Create_Constrained_Components
13011 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
13014 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
13016 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
13017 Conditional_Delay (T_Sub, Corr_Rec);
13020 -- This is a component subtype: it will be frozen in the context of
13021 -- the enclosing record's init_proc, so that discriminant references
13022 -- are resolved to discriminals. (Note: we used to skip freezing
13023 -- altogether in that case, which caused errors downstream for
13024 -- components of a bit packed array type).
13026 Set_Has_Delayed_Freeze (T_Sub);
13030 end Constrain_Corresponding_Record;
13032 -----------------------
13033 -- Constrain_Decimal --
13034 -----------------------
13036 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
13037 T : constant Entity_Id := Entity (Subtype_Mark (S));
13038 C : constant Node_Id := Constraint (S);
13039 Loc : constant Source_Ptr := Sloc (C);
13040 Range_Expr : Node_Id;
13041 Digits_Expr : Node_Id;
13046 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
13048 if Nkind (C) = N_Range_Constraint then
13049 Range_Expr := Range_Expression (C);
13050 Digits_Val := Digits_Value (T);
13053 pragma Assert (Nkind (C) = N_Digits_Constraint);
13055 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13057 Digits_Expr := Digits_Expression (C);
13058 Analyze_And_Resolve (Digits_Expr, Any_Integer);
13060 Check_Digits_Expression (Digits_Expr);
13061 Digits_Val := Expr_Value (Digits_Expr);
13063 if Digits_Val > Digits_Value (T) then
13065 ("digits expression is incompatible with subtype", C);
13066 Digits_Val := Digits_Value (T);
13069 if Present (Range_Constraint (C)) then
13070 Range_Expr := Range_Expression (Range_Constraint (C));
13072 Range_Expr := Empty;
13076 Set_Etype (Def_Id, Base_Type (T));
13077 Set_Size_Info (Def_Id, (T));
13078 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13079 Set_Delta_Value (Def_Id, Delta_Value (T));
13080 Set_Scale_Value (Def_Id, Scale_Value (T));
13081 Set_Small_Value (Def_Id, Small_Value (T));
13082 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
13083 Set_Digits_Value (Def_Id, Digits_Val);
13085 -- Manufacture range from given digits value if no range present
13087 if No (Range_Expr) then
13088 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
13092 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13094 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13097 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13098 Set_Discrete_RM_Size (Def_Id);
13100 -- Unconditionally delay the freeze, since we cannot set size
13101 -- information in all cases correctly until the freeze point.
13103 Set_Has_Delayed_Freeze (Def_Id);
13104 end Constrain_Decimal;
13106 ----------------------------------
13107 -- Constrain_Discriminated_Type --
13108 ----------------------------------
13110 procedure Constrain_Discriminated_Type
13111 (Def_Id : Entity_Id;
13113 Related_Nod : Node_Id;
13114 For_Access : Boolean := False)
13116 E : Entity_Id := Entity (Subtype_Mark (S));
13119 procedure Fixup_Bad_Constraint;
13120 -- Called after finding a bad constraint, and after having posted an
13121 -- appropriate error message. The goal is to leave type Def_Id in as
13122 -- reasonable state as possible.
13124 --------------------------
13125 -- Fixup_Bad_Constraint --
13126 --------------------------
13128 procedure Fixup_Bad_Constraint is
13130 -- Set a reasonable Ekind for the entity. For an incomplete type,
13131 -- we can't do much, but for other types, we can set the proper
13132 -- corresponding subtype kind.
13134 if Ekind (T) = E_Incomplete_Type then
13135 Set_Ekind (Def_Id, Ekind (T));
13137 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13140 -- Set Etype to the known type, to reduce chances of cascaded errors
13142 Set_Etype (Def_Id, E);
13143 Set_Error_Posted (Def_Id);
13144 end Fixup_Bad_Constraint;
13149 Constr : Elist_Id := New_Elmt_List;
13151 -- Start of processing for Constrain_Discriminated_Type
13154 C := Constraint (S);
13156 -- A discriminant constraint is only allowed in a subtype indication,
13157 -- after a subtype mark. This subtype mark must denote either a type
13158 -- with discriminants, or an access type whose designated type is a
13159 -- type with discriminants. A discriminant constraint specifies the
13160 -- values of these discriminants (RM 3.7.2(5)).
13162 T := Base_Type (Entity (Subtype_Mark (S)));
13164 if Is_Access_Type (T) then
13165 T := Designated_Type (T);
13168 -- In an instance it may be necessary to retrieve the full view of a
13169 -- type with unknown discriminants, or a full view with defaulted
13170 -- discriminants. In other contexts the constraint is illegal.
13173 and then Is_Private_Type (T)
13174 and then Present (Full_View (T))
13176 (Has_Unknown_Discriminants (T)
13178 (not Has_Discriminants (T)
13179 and then Has_Discriminants (Full_View (T))
13180 and then Present (Discriminant_Default_Value
13181 (First_Discriminant (Full_View (T))))))
13183 T := Full_View (T);
13184 E := Full_View (E);
13187 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal. Avoid
13188 -- generating an error for access-to-incomplete subtypes.
13190 if Ada_Version >= Ada_2005
13191 and then Ekind (T) = E_Incomplete_Type
13192 and then Nkind (Parent (S)) = N_Subtype_Declaration
13193 and then not Is_Itype (Def_Id)
13195 -- A little sanity check: emit an error message if the type has
13196 -- discriminants to begin with. Type T may be a regular incomplete
13197 -- type or imported via a limited with clause.
13199 if Has_Discriminants (T)
13200 or else (From_Limited_With (T)
13201 and then Present (Non_Limited_View (T))
13202 and then Nkind (Parent (Non_Limited_View (T))) =
13203 N_Full_Type_Declaration
13204 and then Present (Discriminant_Specifications
13205 (Parent (Non_Limited_View (T)))))
13208 ("(Ada 2005) incomplete subtype may not be constrained", C);
13210 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13213 Fixup_Bad_Constraint;
13216 -- Check that the type has visible discriminants. The type may be
13217 -- a private type with unknown discriminants whose full view has
13218 -- discriminants which are invisible.
13220 elsif not Has_Discriminants (T)
13222 (Has_Unknown_Discriminants (T)
13223 and then Is_Private_Type (T))
13225 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13226 Fixup_Bad_Constraint;
13229 elsif Is_Constrained (E)
13230 or else (Ekind (E) = E_Class_Wide_Subtype
13231 and then Present (Discriminant_Constraint (E)))
13233 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13234 Fixup_Bad_Constraint;
13238 -- T may be an unconstrained subtype (e.g. a generic actual). Constraint
13239 -- applies to the base type.
13241 T := Base_Type (T);
13243 Constr := Build_Discriminant_Constraints (T, S);
13245 -- If the list returned was empty we had an error in building the
13246 -- discriminant constraint. We have also already signalled an error
13247 -- in the incomplete type case
13249 if Is_Empty_Elmt_List (Constr) then
13250 Fixup_Bad_Constraint;
13254 Build_Discriminated_Subtype (T, Def_Id, Constr, Related_Nod, For_Access);
13255 end Constrain_Discriminated_Type;
13257 ---------------------------
13258 -- Constrain_Enumeration --
13259 ---------------------------
13261 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13262 T : constant Entity_Id := Entity (Subtype_Mark (S));
13263 C : constant Node_Id := Constraint (S);
13266 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13268 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13270 Set_Etype (Def_Id, Base_Type (T));
13271 Set_Size_Info (Def_Id, (T));
13272 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13273 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13275 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13277 Set_Discrete_RM_Size (Def_Id);
13278 end Constrain_Enumeration;
13280 ----------------------
13281 -- Constrain_Float --
13282 ----------------------
13284 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13285 T : constant Entity_Id := Entity (Subtype_Mark (S));
13291 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13293 Set_Etype (Def_Id, Base_Type (T));
13294 Set_Size_Info (Def_Id, (T));
13295 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13297 -- Process the constraint
13299 C := Constraint (S);
13301 -- Digits constraint present
13303 if Nkind (C) = N_Digits_Constraint then
13305 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13306 Check_Restriction (No_Obsolescent_Features, C);
13308 if Warn_On_Obsolescent_Feature then
13310 ("subtype digits constraint is an " &
13311 "obsolescent feature (RM J.3(8))?j?", C);
13314 D := Digits_Expression (C);
13315 Analyze_And_Resolve (D, Any_Integer);
13316 Check_Digits_Expression (D);
13317 Set_Digits_Value (Def_Id, Expr_Value (D));
13319 -- Check that digits value is in range. Obviously we can do this
13320 -- at compile time, but it is strictly a runtime check, and of
13321 -- course there is an ACVC test that checks this.
13323 if Digits_Value (Def_Id) > Digits_Value (T) then
13324 Error_Msg_Uint_1 := Digits_Value (T);
13325 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13327 Make_Raise_Constraint_Error (Sloc (D),
13328 Reason => CE_Range_Check_Failed);
13329 Insert_Action (Declaration_Node (Def_Id), Rais);
13332 C := Range_Constraint (C);
13334 -- No digits constraint present
13337 Set_Digits_Value (Def_Id, Digits_Value (T));
13340 -- Range constraint present
13342 if Nkind (C) = N_Range_Constraint then
13343 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13345 -- No range constraint present
13348 pragma Assert (No (C));
13349 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13352 Set_Is_Constrained (Def_Id);
13353 end Constrain_Float;
13355 ---------------------
13356 -- Constrain_Index --
13357 ---------------------
13359 procedure Constrain_Index
13362 Related_Nod : Node_Id;
13363 Related_Id : Entity_Id;
13364 Suffix : Character;
13365 Suffix_Index : Nat)
13367 Def_Id : Entity_Id;
13368 R : Node_Id := Empty;
13369 T : constant Entity_Id := Etype (Index);
13373 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13374 Set_Etype (Def_Id, Base_Type (T));
13376 if Nkind (S) = N_Range
13378 (Nkind (S) = N_Attribute_Reference
13379 and then Attribute_Name (S) = Name_Range)
13381 -- A Range attribute will be transformed into N_Range by Resolve
13387 Process_Range_Expr_In_Decl (R, T);
13389 if not Error_Posted (S)
13391 (Nkind (S) /= N_Range
13392 or else not Covers (T, (Etype (Low_Bound (S))))
13393 or else not Covers (T, (Etype (High_Bound (S)))))
13395 if Base_Type (T) /= Any_Type
13396 and then Etype (Low_Bound (S)) /= Any_Type
13397 and then Etype (High_Bound (S)) /= Any_Type
13399 Error_Msg_N ("range expected", S);
13403 elsif Nkind (S) = N_Subtype_Indication then
13405 -- The parser has verified that this is a discrete indication
13407 Resolve_Discrete_Subtype_Indication (S, T);
13408 Bad_Predicated_Subtype_Use
13409 ("subtype& has predicate, not allowed in index constraint",
13410 S, Entity (Subtype_Mark (S)));
13412 R := Range_Expression (Constraint (S));
13414 -- Capture values of bounds and generate temporaries for them if
13415 -- needed, since checks may cause duplication of the expressions
13416 -- which must not be reevaluated.
13418 -- The forced evaluation removes side effects from expressions, which
13419 -- should occur also in GNATprove mode. Otherwise, we end up with
13420 -- unexpected insertions of actions at places where this is not
13421 -- supposed to occur, e.g. on default parameters of a call.
13423 if Expander_Active or GNATprove_Mode then
13425 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13427 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13430 elsif Nkind (S) = N_Discriminant_Association then
13432 -- Syntactically valid in subtype indication
13434 Error_Msg_N ("invalid index constraint", S);
13435 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13438 -- Subtype_Mark case, no anonymous subtypes to construct
13443 if Is_Entity_Name (S) then
13444 if not Is_Type (Entity (S)) then
13445 Error_Msg_N ("expect subtype mark for index constraint", S);
13447 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13448 Wrong_Type (S, Base_Type (T));
13450 -- Check error of subtype with predicate in index constraint
13453 Bad_Predicated_Subtype_Use
13454 ("subtype& has predicate, not allowed in index constraint",
13461 Error_Msg_N ("invalid index constraint", S);
13462 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13467 -- Complete construction of the Itype
13469 if Is_Modular_Integer_Type (T) then
13470 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13472 elsif Is_Integer_Type (T) then
13473 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13476 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13477 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13478 Set_First_Literal (Def_Id, First_Literal (T));
13481 Set_Size_Info (Def_Id, (T));
13482 Set_RM_Size (Def_Id, RM_Size (T));
13483 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13485 Set_Scalar_Range (Def_Id, R);
13487 Set_Etype (S, Def_Id);
13488 Set_Discrete_RM_Size (Def_Id);
13489 end Constrain_Index;
13491 -----------------------
13492 -- Constrain_Integer --
13493 -----------------------
13495 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13496 T : constant Entity_Id := Entity (Subtype_Mark (S));
13497 C : constant Node_Id := Constraint (S);
13500 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13502 if Is_Modular_Integer_Type (T) then
13503 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13505 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13508 Set_Etype (Def_Id, Base_Type (T));
13509 Set_Size_Info (Def_Id, (T));
13510 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13511 Set_Discrete_RM_Size (Def_Id);
13512 end Constrain_Integer;
13514 ------------------------------
13515 -- Constrain_Ordinary_Fixed --
13516 ------------------------------
13518 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13519 T : constant Entity_Id := Entity (Subtype_Mark (S));
13525 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13526 Set_Etype (Def_Id, Base_Type (T));
13527 Set_Size_Info (Def_Id, (T));
13528 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13529 Set_Small_Value (Def_Id, Small_Value (T));
13531 -- Process the constraint
13533 C := Constraint (S);
13535 -- Delta constraint present
13537 if Nkind (C) = N_Delta_Constraint then
13539 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13540 Check_Restriction (No_Obsolescent_Features, C);
13542 if Warn_On_Obsolescent_Feature then
13544 ("subtype delta constraint is an " &
13545 "obsolescent feature (RM J.3(7))?j?");
13548 D := Delta_Expression (C);
13549 Analyze_And_Resolve (D, Any_Real);
13550 Check_Delta_Expression (D);
13551 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13553 -- Check that delta value is in range. Obviously we can do this
13554 -- at compile time, but it is strictly a runtime check, and of
13555 -- course there is an ACVC test that checks this.
13557 if Delta_Value (Def_Id) < Delta_Value (T) then
13558 Error_Msg_N ("??delta value is too small", D);
13560 Make_Raise_Constraint_Error (Sloc (D),
13561 Reason => CE_Range_Check_Failed);
13562 Insert_Action (Declaration_Node (Def_Id), Rais);
13565 C := Range_Constraint (C);
13567 -- No delta constraint present
13570 Set_Delta_Value (Def_Id, Delta_Value (T));
13573 -- Range constraint present
13575 if Nkind (C) = N_Range_Constraint then
13576 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13578 -- No range constraint present
13581 pragma Assert (No (C));
13582 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13585 Set_Discrete_RM_Size (Def_Id);
13587 -- Unconditionally delay the freeze, since we cannot set size
13588 -- information in all cases correctly until the freeze point.
13590 Set_Has_Delayed_Freeze (Def_Id);
13591 end Constrain_Ordinary_Fixed;
13593 -----------------------
13594 -- Contain_Interface --
13595 -----------------------
13597 function Contain_Interface
13598 (Iface : Entity_Id;
13599 Ifaces : Elist_Id) return Boolean
13601 Iface_Elmt : Elmt_Id;
13604 if Present (Ifaces) then
13605 Iface_Elmt := First_Elmt (Ifaces);
13606 while Present (Iface_Elmt) loop
13607 if Node (Iface_Elmt) = Iface then
13611 Next_Elmt (Iface_Elmt);
13616 end Contain_Interface;
13618 ---------------------------
13619 -- Convert_Scalar_Bounds --
13620 ---------------------------
13622 procedure Convert_Scalar_Bounds
13624 Parent_Type : Entity_Id;
13625 Derived_Type : Entity_Id;
13628 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13635 -- Defend against previous errors
13637 if No (Scalar_Range (Derived_Type)) then
13638 Check_Error_Detected;
13642 Lo := Build_Scalar_Bound
13643 (Type_Low_Bound (Derived_Type),
13644 Parent_Type, Implicit_Base);
13646 Hi := Build_Scalar_Bound
13647 (Type_High_Bound (Derived_Type),
13648 Parent_Type, Implicit_Base);
13655 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13657 Set_Parent (Rng, N);
13658 Set_Scalar_Range (Derived_Type, Rng);
13660 -- Analyze the bounds
13662 Analyze_And_Resolve (Lo, Implicit_Base);
13663 Analyze_And_Resolve (Hi, Implicit_Base);
13665 -- Analyze the range itself, except that we do not analyze it if
13666 -- the bounds are real literals, and we have a fixed-point type.
13667 -- The reason for this is that we delay setting the bounds in this
13668 -- case till we know the final Small and Size values (see circuit
13669 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13671 if Is_Fixed_Point_Type (Parent_Type)
13672 and then Nkind (Lo) = N_Real_Literal
13673 and then Nkind (Hi) = N_Real_Literal
13677 -- Here we do the analysis of the range
13679 -- Note: we do this manually, since if we do a normal Analyze and
13680 -- Resolve call, there are problems with the conversions used for
13681 -- the derived type range.
13684 Set_Etype (Rng, Implicit_Base);
13685 Set_Analyzed (Rng, True);
13687 end Convert_Scalar_Bounds;
13689 -------------------
13690 -- Copy_And_Swap --
13691 -------------------
13693 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13695 -- Initialize new full declaration entity by copying the pertinent
13696 -- fields of the corresponding private declaration entity.
13698 -- We temporarily set Ekind to a value appropriate for a type to
13699 -- avoid assert failures in Einfo from checking for setting type
13700 -- attributes on something that is not a type. Ekind (Priv) is an
13701 -- appropriate choice, since it allowed the attributes to be set
13702 -- in the first place. This Ekind value will be modified later.
13704 Set_Ekind (Full, Ekind (Priv));
13706 -- Also set Etype temporarily to Any_Type, again, in the absence
13707 -- of errors, it will be properly reset, and if there are errors,
13708 -- then we want a value of Any_Type to remain.
13710 Set_Etype (Full, Any_Type);
13712 -- Now start copying attributes
13714 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13716 if Has_Discriminants (Full) then
13717 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13718 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13721 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13722 Set_Homonym (Full, Homonym (Priv));
13723 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13724 Set_Is_Public (Full, Is_Public (Priv));
13725 Set_Is_Pure (Full, Is_Pure (Priv));
13726 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13727 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13728 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13729 Set_Has_Pragma_Unreferenced_Objects
13730 (Full, Has_Pragma_Unreferenced_Objects
13733 Conditional_Delay (Full, Priv);
13735 if Is_Tagged_Type (Full) then
13736 Set_Direct_Primitive_Operations
13737 (Full, Direct_Primitive_Operations (Priv));
13738 Set_No_Tagged_Streams_Pragma
13739 (Full, No_Tagged_Streams_Pragma (Priv));
13741 if Is_Base_Type (Priv) then
13742 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13746 Set_Is_Volatile (Full, Is_Volatile (Priv));
13747 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13748 Set_Scope (Full, Scope (Priv));
13749 Set_Next_Entity (Full, Next_Entity (Priv));
13750 Set_First_Entity (Full, First_Entity (Priv));
13751 Set_Last_Entity (Full, Last_Entity (Priv));
13753 -- If access types have been recorded for later handling, keep them in
13754 -- the full view so that they get handled when the full view freeze
13755 -- node is expanded.
13757 if Present (Freeze_Node (Priv))
13758 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13760 Ensure_Freeze_Node (Full);
13761 Set_Access_Types_To_Process
13762 (Freeze_Node (Full),
13763 Access_Types_To_Process (Freeze_Node (Priv)));
13766 -- Swap the two entities. Now Private is the full type entity and Full
13767 -- is the private one. They will be swapped back at the end of the
13768 -- private part. This swapping ensures that the entity that is visible
13769 -- in the private part is the full declaration.
13771 Exchange_Entities (Priv, Full);
13772 Append_Entity (Full, Scope (Full));
13775 -------------------------------------
13776 -- Copy_Array_Base_Type_Attributes --
13777 -------------------------------------
13779 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13781 Set_Component_Alignment (T1, Component_Alignment (T2));
13782 Set_Component_Type (T1, Component_Type (T2));
13783 Set_Component_Size (T1, Component_Size (T2));
13784 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13785 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13786 Propagate_Concurrent_Flags (T1, T2);
13787 Set_Is_Packed (T1, Is_Packed (T2));
13788 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13789 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13790 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13791 end Copy_Array_Base_Type_Attributes;
13793 -----------------------------------
13794 -- Copy_Array_Subtype_Attributes --
13795 -----------------------------------
13797 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13799 Set_Size_Info (T1, T2);
13801 Set_First_Index (T1, First_Index (T2));
13802 Set_Is_Aliased (T1, Is_Aliased (T2));
13803 Set_Is_Volatile (T1, Is_Volatile (T2));
13804 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13805 Set_Is_Constrained (T1, Is_Constrained (T2));
13806 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13807 Inherit_Rep_Item_Chain (T1, T2);
13808 Set_Convention (T1, Convention (T2));
13809 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13810 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13811 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13812 end Copy_Array_Subtype_Attributes;
13814 -----------------------------------
13815 -- Create_Constrained_Components --
13816 -----------------------------------
13818 procedure Create_Constrained_Components
13820 Decl_Node : Node_Id;
13822 Constraints : Elist_Id)
13824 Loc : constant Source_Ptr := Sloc (Subt);
13825 Comp_List : constant Elist_Id := New_Elmt_List;
13826 Parent_Type : constant Entity_Id := Etype (Typ);
13827 Assoc_List : constant List_Id := New_List;
13828 Discr_Val : Elmt_Id;
13832 Is_Static : Boolean := True;
13834 procedure Collect_Fixed_Components (Typ : Entity_Id);
13835 -- Collect parent type components that do not appear in a variant part
13837 procedure Create_All_Components;
13838 -- Iterate over Comp_List to create the components of the subtype
13840 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13841 -- Creates a new component from Old_Compon, copying all the fields from
13842 -- it, including its Etype, inserts the new component in the Subt entity
13843 -- chain and returns the new component.
13845 function Is_Variant_Record (T : Entity_Id) return Boolean;
13846 -- If true, and discriminants are static, collect only components from
13847 -- variants selected by discriminant values.
13849 ------------------------------
13850 -- Collect_Fixed_Components --
13851 ------------------------------
13853 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13855 -- Build association list for discriminants, and find components of the
13856 -- variant part selected by the values of the discriminants.
13858 Old_C := First_Discriminant (Typ);
13859 Discr_Val := First_Elmt (Constraints);
13860 while Present (Old_C) loop
13861 Append_To (Assoc_List,
13862 Make_Component_Association (Loc,
13863 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13864 Expression => New_Copy (Node (Discr_Val))));
13866 Next_Elmt (Discr_Val);
13867 Next_Discriminant (Old_C);
13870 -- The tag and the possible parent component are unconditionally in
13873 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13874 Old_C := First_Component (Typ);
13875 while Present (Old_C) loop
13876 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13877 Append_Elmt (Old_C, Comp_List);
13880 Next_Component (Old_C);
13883 end Collect_Fixed_Components;
13885 ---------------------------
13886 -- Create_All_Components --
13887 ---------------------------
13889 procedure Create_All_Components is
13893 Comp := First_Elmt (Comp_List);
13894 while Present (Comp) loop
13895 Old_C := Node (Comp);
13896 New_C := Create_Component (Old_C);
13900 Constrain_Component_Type
13901 (Old_C, Subt, Decl_Node, Typ, Constraints));
13902 Set_Is_Public (New_C, Is_Public (Subt));
13906 end Create_All_Components;
13908 ----------------------
13909 -- Create_Component --
13910 ----------------------
13912 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13913 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13916 if Ekind (Old_Compon) = E_Discriminant
13917 and then Is_Completely_Hidden (Old_Compon)
13919 -- This is a shadow discriminant created for a discriminant of
13920 -- the parent type, which needs to be present in the subtype.
13921 -- Give the shadow discriminant an internal name that cannot
13922 -- conflict with that of visible components.
13924 Set_Chars (New_Compon, New_Internal_Name ('C'));
13927 -- Set the parent so we have a proper link for freezing etc. This is
13928 -- not a real parent pointer, since of course our parent does not own
13929 -- up to us and reference us, we are an illegitimate child of the
13930 -- original parent.
13932 Set_Parent (New_Compon, Parent (Old_Compon));
13934 -- If the old component's Esize was already determined and is a
13935 -- static value, then the new component simply inherits it. Otherwise
13936 -- the old component's size may require run-time determination, but
13937 -- the new component's size still might be statically determinable
13938 -- (if, for example it has a static constraint). In that case we want
13939 -- Layout_Type to recompute the component's size, so we reset its
13940 -- size and positional fields.
13942 if Frontend_Layout_On_Target
13943 and then not Known_Static_Esize (Old_Compon)
13945 Set_Esize (New_Compon, Uint_0);
13946 Init_Normalized_First_Bit (New_Compon);
13947 Init_Normalized_Position (New_Compon);
13948 Init_Normalized_Position_Max (New_Compon);
13951 -- We do not want this node marked as Comes_From_Source, since
13952 -- otherwise it would get first class status and a separate cross-
13953 -- reference line would be generated. Illegitimate children do not
13954 -- rate such recognition.
13956 Set_Comes_From_Source (New_Compon, False);
13958 -- But it is a real entity, and a birth certificate must be properly
13959 -- registered by entering it into the entity list.
13961 Enter_Name (New_Compon);
13964 end Create_Component;
13966 -----------------------
13967 -- Is_Variant_Record --
13968 -----------------------
13970 function Is_Variant_Record (T : Entity_Id) return Boolean is
13972 return Nkind (Parent (T)) = N_Full_Type_Declaration
13973 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13974 and then Present (Component_List (Type_Definition (Parent (T))))
13977 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13978 end Is_Variant_Record;
13980 -- Start of processing for Create_Constrained_Components
13983 pragma Assert (Subt /= Base_Type (Subt));
13984 pragma Assert (Typ = Base_Type (Typ));
13986 Set_First_Entity (Subt, Empty);
13987 Set_Last_Entity (Subt, Empty);
13989 -- Check whether constraint is fully static, in which case we can
13990 -- optimize the list of components.
13992 Discr_Val := First_Elmt (Constraints);
13993 while Present (Discr_Val) loop
13994 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13995 Is_Static := False;
13999 Next_Elmt (Discr_Val);
14002 Set_Has_Static_Discriminants (Subt, Is_Static);
14006 -- Inherit the discriminants of the parent type
14008 Add_Discriminants : declare
14014 Old_C := First_Discriminant (Typ);
14016 while Present (Old_C) loop
14017 Num_Disc := Num_Disc + 1;
14018 New_C := Create_Component (Old_C);
14019 Set_Is_Public (New_C, Is_Public (Subt));
14020 Next_Discriminant (Old_C);
14023 -- For an untagged derived subtype, the number of discriminants may
14024 -- be smaller than the number of inherited discriminants, because
14025 -- several of them may be renamed by a single new discriminant or
14026 -- constrained. In this case, add the hidden discriminants back into
14027 -- the subtype, because they need to be present if the optimizer of
14028 -- the GCC 4.x back-end decides to break apart assignments between
14029 -- objects using the parent view into member-wise assignments.
14033 if Is_Derived_Type (Typ)
14034 and then not Is_Tagged_Type (Typ)
14036 Old_C := First_Stored_Discriminant (Typ);
14038 while Present (Old_C) loop
14039 Num_Gird := Num_Gird + 1;
14040 Next_Stored_Discriminant (Old_C);
14044 if Num_Gird > Num_Disc then
14046 -- Find out multiple uses of new discriminants, and add hidden
14047 -- components for the extra renamed discriminants. We recognize
14048 -- multiple uses through the Corresponding_Discriminant of a
14049 -- new discriminant: if it constrains several old discriminants,
14050 -- this field points to the last one in the parent type. The
14051 -- stored discriminants of the derived type have the same name
14052 -- as those of the parent.
14056 New_Discr : Entity_Id;
14057 Old_Discr : Entity_Id;
14060 Constr := First_Elmt (Stored_Constraint (Typ));
14061 Old_Discr := First_Stored_Discriminant (Typ);
14062 while Present (Constr) loop
14063 if Is_Entity_Name (Node (Constr))
14064 and then Ekind (Entity (Node (Constr))) = E_Discriminant
14066 New_Discr := Entity (Node (Constr));
14068 if Chars (Corresponding_Discriminant (New_Discr)) /=
14071 -- The new discriminant has been used to rename a
14072 -- subsequent old discriminant. Introduce a shadow
14073 -- component for the current old discriminant.
14075 New_C := Create_Component (Old_Discr);
14076 Set_Original_Record_Component (New_C, Old_Discr);
14080 -- The constraint has eliminated the old discriminant.
14081 -- Introduce a shadow component.
14083 New_C := Create_Component (Old_Discr);
14084 Set_Original_Record_Component (New_C, Old_Discr);
14087 Next_Elmt (Constr);
14088 Next_Stored_Discriminant (Old_Discr);
14092 end Add_Discriminants;
14095 and then Is_Variant_Record (Typ)
14097 Collect_Fixed_Components (Typ);
14099 Gather_Components (
14101 Component_List (Type_Definition (Parent (Typ))),
14102 Governed_By => Assoc_List,
14104 Report_Errors => Errors);
14105 pragma Assert (not Errors);
14107 Create_All_Components;
14109 -- If the subtype declaration is created for a tagged type derivation
14110 -- with constraints, we retrieve the record definition of the parent
14111 -- type to select the components of the proper variant.
14114 and then Is_Tagged_Type (Typ)
14115 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14117 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14118 and then Is_Variant_Record (Parent_Type)
14120 Collect_Fixed_Components (Typ);
14124 Component_List (Type_Definition (Parent (Parent_Type))),
14125 Governed_By => Assoc_List,
14127 Report_Errors => Errors);
14129 -- Note: previously there was a check at this point that no errors
14130 -- were detected. As a consequence of AI05-220 there may be an error
14131 -- if an inherited discriminant that controls a variant has a non-
14132 -- static constraint.
14134 -- If the tagged derivation has a type extension, collect all the
14135 -- new components therein.
14137 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14139 Old_C := First_Component (Typ);
14140 while Present (Old_C) loop
14141 if Original_Record_Component (Old_C) = Old_C
14142 and then Chars (Old_C) /= Name_uTag
14143 and then Chars (Old_C) /= Name_uParent
14145 Append_Elmt (Old_C, Comp_List);
14148 Next_Component (Old_C);
14152 Create_All_Components;
14155 -- If discriminants are not static, or if this is a multi-level type
14156 -- extension, we have to include all components of the parent type.
14158 Old_C := First_Component (Typ);
14159 while Present (Old_C) loop
14160 New_C := Create_Component (Old_C);
14164 Constrain_Component_Type
14165 (Old_C, Subt, Decl_Node, Typ, Constraints));
14166 Set_Is_Public (New_C, Is_Public (Subt));
14168 Next_Component (Old_C);
14173 end Create_Constrained_Components;
14175 ------------------------------------------
14176 -- Decimal_Fixed_Point_Type_Declaration --
14177 ------------------------------------------
14179 procedure Decimal_Fixed_Point_Type_Declaration
14183 Loc : constant Source_Ptr := Sloc (Def);
14184 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14185 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14186 Implicit_Base : Entity_Id;
14193 Check_SPARK_05_Restriction
14194 ("decimal fixed point type is not allowed", Def);
14195 Check_Restriction (No_Fixed_Point, Def);
14197 -- Create implicit base type
14200 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14201 Set_Etype (Implicit_Base, Implicit_Base);
14203 -- Analyze and process delta expression
14205 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14207 Check_Delta_Expression (Delta_Expr);
14208 Delta_Val := Expr_Value_R (Delta_Expr);
14210 -- Check delta is power of 10, and determine scale value from it
14216 Scale_Val := Uint_0;
14219 if Val < Ureal_1 then
14220 while Val < Ureal_1 loop
14221 Val := Val * Ureal_10;
14222 Scale_Val := Scale_Val + 1;
14225 if Scale_Val > 18 then
14226 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14227 Scale_Val := UI_From_Int (+18);
14231 while Val > Ureal_1 loop
14232 Val := Val / Ureal_10;
14233 Scale_Val := Scale_Val - 1;
14236 if Scale_Val < -18 then
14237 Error_Msg_N ("scale is less than minimum value of -18", Def);
14238 Scale_Val := UI_From_Int (-18);
14242 if Val /= Ureal_1 then
14243 Error_Msg_N ("delta expression must be a power of 10", Def);
14244 Delta_Val := Ureal_10 ** (-Scale_Val);
14248 -- Set delta, scale and small (small = delta for decimal type)
14250 Set_Delta_Value (Implicit_Base, Delta_Val);
14251 Set_Scale_Value (Implicit_Base, Scale_Val);
14252 Set_Small_Value (Implicit_Base, Delta_Val);
14254 -- Analyze and process digits expression
14256 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14257 Check_Digits_Expression (Digs_Expr);
14258 Digs_Val := Expr_Value (Digs_Expr);
14260 if Digs_Val > 18 then
14261 Digs_Val := UI_From_Int (+18);
14262 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14265 Set_Digits_Value (Implicit_Base, Digs_Val);
14266 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14268 -- Set range of base type from digits value for now. This will be
14269 -- expanded to represent the true underlying base range by Freeze.
14271 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14273 -- Note: We leave size as zero for now, size will be set at freeze
14274 -- time. We have to do this for ordinary fixed-point, because the size
14275 -- depends on the specified small, and we might as well do the same for
14276 -- decimal fixed-point.
14278 pragma Assert (Esize (Implicit_Base) = Uint_0);
14280 -- If there are bounds given in the declaration use them as the
14281 -- bounds of the first named subtype.
14283 if Present (Real_Range_Specification (Def)) then
14285 RRS : constant Node_Id := Real_Range_Specification (Def);
14286 Low : constant Node_Id := Low_Bound (RRS);
14287 High : constant Node_Id := High_Bound (RRS);
14292 Analyze_And_Resolve (Low, Any_Real);
14293 Analyze_And_Resolve (High, Any_Real);
14294 Check_Real_Bound (Low);
14295 Check_Real_Bound (High);
14296 Low_Val := Expr_Value_R (Low);
14297 High_Val := Expr_Value_R (High);
14299 if Low_Val < (-Bound_Val) then
14301 ("range low bound too small for digits value", Low);
14302 Low_Val := -Bound_Val;
14305 if High_Val > Bound_Val then
14307 ("range high bound too large for digits value", High);
14308 High_Val := Bound_Val;
14311 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14314 -- If no explicit range, use range that corresponds to given
14315 -- digits value. This will end up as the final range for the
14319 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14322 -- Complete entity for first subtype. The inheritance of the rep item
14323 -- chain ensures that SPARK-related pragmas are not clobbered when the
14324 -- decimal fixed point type acts as a full view of a private type.
14326 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14327 Set_Etype (T, Implicit_Base);
14328 Set_Size_Info (T, Implicit_Base);
14329 Inherit_Rep_Item_Chain (T, Implicit_Base);
14330 Set_Digits_Value (T, Digs_Val);
14331 Set_Delta_Value (T, Delta_Val);
14332 Set_Small_Value (T, Delta_Val);
14333 Set_Scale_Value (T, Scale_Val);
14334 Set_Is_Constrained (T);
14335 end Decimal_Fixed_Point_Type_Declaration;
14337 -----------------------------------
14338 -- Derive_Progenitor_Subprograms --
14339 -----------------------------------
14341 procedure Derive_Progenitor_Subprograms
14342 (Parent_Type : Entity_Id;
14343 Tagged_Type : Entity_Id)
14348 Iface_Elmt : Elmt_Id;
14349 Iface_Subp : Entity_Id;
14350 New_Subp : Entity_Id := Empty;
14351 Prim_Elmt : Elmt_Id;
14356 pragma Assert (Ada_Version >= Ada_2005
14357 and then Is_Record_Type (Tagged_Type)
14358 and then Is_Tagged_Type (Tagged_Type)
14359 and then Has_Interfaces (Tagged_Type));
14361 -- Step 1: Transfer to the full-view primitives associated with the
14362 -- partial-view that cover interface primitives. Conceptually this
14363 -- work should be done later by Process_Full_View; done here to
14364 -- simplify its implementation at later stages. It can be safely
14365 -- done here because interfaces must be visible in the partial and
14366 -- private view (RM 7.3(7.3/2)).
14368 -- Small optimization: This work is only required if the parent may
14369 -- have entities whose Alias attribute reference an interface primitive.
14370 -- Such a situation may occur if the parent is an abstract type and the
14371 -- primitive has not been yet overridden or if the parent is a generic
14372 -- formal type covering interfaces.
14374 -- If the tagged type is not abstract, it cannot have abstract
14375 -- primitives (the only entities in the list of primitives of
14376 -- non-abstract tagged types that can reference abstract primitives
14377 -- through its Alias attribute are the internal entities that have
14378 -- attribute Interface_Alias, and these entities are generated later
14379 -- by Add_Internal_Interface_Entities).
14381 if In_Private_Part (Current_Scope)
14382 and then (Is_Abstract_Type (Parent_Type)
14384 Is_Generic_Type (Parent_Type))
14386 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14387 while Present (Elmt) loop
14388 Subp := Node (Elmt);
14390 -- At this stage it is not possible to have entities in the list
14391 -- of primitives that have attribute Interface_Alias.
14393 pragma Assert (No (Interface_Alias (Subp)));
14395 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14397 if Is_Interface (Typ) then
14398 E := Find_Primitive_Covering_Interface
14399 (Tagged_Type => Tagged_Type,
14400 Iface_Prim => Subp);
14403 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14405 Replace_Elmt (Elmt, E);
14406 Remove_Homonym (Subp);
14414 -- Step 2: Add primitives of progenitors that are not implemented by
14415 -- parents of Tagged_Type.
14417 if Present (Interfaces (Base_Type (Tagged_Type))) then
14418 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14419 while Present (Iface_Elmt) loop
14420 Iface := Node (Iface_Elmt);
14422 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14423 while Present (Prim_Elmt) loop
14424 Iface_Subp := Node (Prim_Elmt);
14426 -- Exclude derivation of predefined primitives except those
14427 -- that come from source, or are inherited from one that comes
14428 -- from source. Required to catch declarations of equality
14429 -- operators of interfaces. For example:
14431 -- type Iface is interface;
14432 -- function "=" (Left, Right : Iface) return Boolean;
14434 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14435 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14437 E := Find_Primitive_Covering_Interface
14438 (Tagged_Type => Tagged_Type,
14439 Iface_Prim => Iface_Subp);
14441 -- If not found we derive a new primitive leaving its alias
14442 -- attribute referencing the interface primitive.
14446 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14448 -- Ada 2012 (AI05-0197): If the covering primitive's name
14449 -- differs from the name of the interface primitive then it
14450 -- is a private primitive inherited from a parent type. In
14451 -- such case, given that Tagged_Type covers the interface,
14452 -- the inherited private primitive becomes visible. For such
14453 -- purpose we add a new entity that renames the inherited
14454 -- private primitive.
14456 elsif Chars (E) /= Chars (Iface_Subp) then
14457 pragma Assert (Has_Suffix (E, 'P'));
14459 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14460 Set_Alias (New_Subp, E);
14461 Set_Is_Abstract_Subprogram (New_Subp,
14462 Is_Abstract_Subprogram (E));
14464 -- Propagate to the full view interface entities associated
14465 -- with the partial view.
14467 elsif In_Private_Part (Current_Scope)
14468 and then Present (Alias (E))
14469 and then Alias (E) = Iface_Subp
14471 List_Containing (Parent (E)) /=
14472 Private_Declarations
14474 (Unit_Declaration_Node (Current_Scope)))
14476 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14480 Next_Elmt (Prim_Elmt);
14483 Next_Elmt (Iface_Elmt);
14486 end Derive_Progenitor_Subprograms;
14488 -----------------------
14489 -- Derive_Subprogram --
14490 -----------------------
14492 procedure Derive_Subprogram
14493 (New_Subp : in out Entity_Id;
14494 Parent_Subp : Entity_Id;
14495 Derived_Type : Entity_Id;
14496 Parent_Type : Entity_Id;
14497 Actual_Subp : Entity_Id := Empty)
14499 Formal : Entity_Id;
14500 -- Formal parameter of parent primitive operation
14502 Formal_Of_Actual : Entity_Id;
14503 -- Formal parameter of actual operation, when the derivation is to
14504 -- create a renaming for a primitive operation of an actual in an
14507 New_Formal : Entity_Id;
14508 -- Formal of inherited operation
14510 Visible_Subp : Entity_Id := Parent_Subp;
14512 function Is_Private_Overriding return Boolean;
14513 -- If Subp is a private overriding of a visible operation, the inherited
14514 -- operation derives from the overridden op (even though its body is the
14515 -- overriding one) and the inherited operation is visible now. See
14516 -- sem_disp to see the full details of the handling of the overridden
14517 -- subprogram, which is removed from the list of primitive operations of
14518 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14519 -- and used to diagnose abstract operations that need overriding in the
14522 procedure Replace_Type (Id, New_Id : Entity_Id);
14523 -- When the type is an anonymous access type, create a new access type
14524 -- designating the derived type.
14526 procedure Set_Derived_Name;
14527 -- This procedure sets the appropriate Chars name for New_Subp. This
14528 -- is normally just a copy of the parent name. An exception arises for
14529 -- type support subprograms, where the name is changed to reflect the
14530 -- name of the derived type, e.g. if type foo is derived from type bar,
14531 -- then a procedure barDA is derived with a name fooDA.
14533 ---------------------------
14534 -- Is_Private_Overriding --
14535 ---------------------------
14537 function Is_Private_Overriding return Boolean is
14541 -- If the parent is not a dispatching operation there is no
14542 -- need to investigate overridings
14544 if not Is_Dispatching_Operation (Parent_Subp) then
14548 -- The visible operation that is overridden is a homonym of the
14549 -- parent subprogram. We scan the homonym chain to find the one
14550 -- whose alias is the subprogram we are deriving.
14552 Prev := Current_Entity (Parent_Subp);
14553 while Present (Prev) loop
14554 if Ekind (Prev) = Ekind (Parent_Subp)
14555 and then Alias (Prev) = Parent_Subp
14556 and then Scope (Parent_Subp) = Scope (Prev)
14557 and then not Is_Hidden (Prev)
14559 Visible_Subp := Prev;
14563 Prev := Homonym (Prev);
14567 end Is_Private_Overriding;
14573 procedure Replace_Type (Id, New_Id : Entity_Id) is
14574 Id_Type : constant Entity_Id := Etype (Id);
14575 Acc_Type : Entity_Id;
14576 Par : constant Node_Id := Parent (Derived_Type);
14579 -- When the type is an anonymous access type, create a new access
14580 -- type designating the derived type. This itype must be elaborated
14581 -- at the point of the derivation, not on subsequent calls that may
14582 -- be out of the proper scope for Gigi, so we insert a reference to
14583 -- it after the derivation.
14585 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14587 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14590 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14591 and then Present (Full_View (Desig_Typ))
14592 and then not Is_Private_Type (Parent_Type)
14594 Desig_Typ := Full_View (Desig_Typ);
14597 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14599 -- Ada 2005 (AI-251): Handle also derivations of abstract
14600 -- interface primitives.
14602 or else (Is_Interface (Desig_Typ)
14603 and then not Is_Class_Wide_Type (Desig_Typ))
14605 Acc_Type := New_Copy (Id_Type);
14606 Set_Etype (Acc_Type, Acc_Type);
14607 Set_Scope (Acc_Type, New_Subp);
14609 -- Set size of anonymous access type. If we have an access
14610 -- to an unconstrained array, this is a fat pointer, so it
14611 -- is sizes at twice addtress size.
14613 if Is_Array_Type (Desig_Typ)
14614 and then not Is_Constrained (Desig_Typ)
14616 Init_Size (Acc_Type, 2 * System_Address_Size);
14618 -- Other cases use a thin pointer
14621 Init_Size (Acc_Type, System_Address_Size);
14624 -- Set remaining characterstics of anonymous access type
14626 Init_Alignment (Acc_Type);
14627 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14629 Set_Etype (New_Id, Acc_Type);
14630 Set_Scope (New_Id, New_Subp);
14632 -- Create a reference to it
14634 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14637 Set_Etype (New_Id, Id_Type);
14641 -- In Ada2012, a formal may have an incomplete type but the type
14642 -- derivation that inherits the primitive follows the full view.
14644 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14646 (Ekind (Id_Type) = E_Record_Type_With_Private
14647 and then Present (Full_View (Id_Type))
14649 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14651 (Ada_Version >= Ada_2012
14652 and then Ekind (Id_Type) = E_Incomplete_Type
14653 and then Full_View (Id_Type) = Parent_Type)
14655 -- Constraint checks on formals are generated during expansion,
14656 -- based on the signature of the original subprogram. The bounds
14657 -- of the derived type are not relevant, and thus we can use
14658 -- the base type for the formals. However, the return type may be
14659 -- used in a context that requires that the proper static bounds
14660 -- be used (a case statement, for example) and for those cases
14661 -- we must use the derived type (first subtype), not its base.
14663 -- If the derived_type_definition has no constraints, we know that
14664 -- the derived type has the same constraints as the first subtype
14665 -- of the parent, and we can also use it rather than its base,
14666 -- which can lead to more efficient code.
14668 if Etype (Id) = Parent_Type then
14669 if Is_Scalar_Type (Parent_Type)
14671 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14673 Set_Etype (New_Id, Derived_Type);
14675 elsif Nkind (Par) = N_Full_Type_Declaration
14677 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14680 (Subtype_Indication (Type_Definition (Par)))
14682 Set_Etype (New_Id, Derived_Type);
14685 Set_Etype (New_Id, Base_Type (Derived_Type));
14689 Set_Etype (New_Id, Base_Type (Derived_Type));
14693 Set_Etype (New_Id, Etype (Id));
14697 ----------------------
14698 -- Set_Derived_Name --
14699 ----------------------
14701 procedure Set_Derived_Name is
14702 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14704 if Nm = TSS_Null then
14705 Set_Chars (New_Subp, Chars (Parent_Subp));
14707 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14709 end Set_Derived_Name;
14711 -- Start of processing for Derive_Subprogram
14714 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14715 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14717 -- Check whether the inherited subprogram is a private operation that
14718 -- should be inherited but not yet made visible. Such subprograms can
14719 -- become visible at a later point (e.g., the private part of a public
14720 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14721 -- following predicate is true, then this is not such a private
14722 -- operation and the subprogram simply inherits the name of the parent
14723 -- subprogram. Note the special check for the names of controlled
14724 -- operations, which are currently exempted from being inherited with
14725 -- a hidden name because they must be findable for generation of
14726 -- implicit run-time calls.
14728 if not Is_Hidden (Parent_Subp)
14729 or else Is_Internal (Parent_Subp)
14730 or else Is_Private_Overriding
14731 or else Is_Internal_Name (Chars (Parent_Subp))
14732 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14738 -- An inherited dispatching equality will be overridden by an internally
14739 -- generated one, or by an explicit one, so preserve its name and thus
14740 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14741 -- private operation it may become invisible if the full view has
14742 -- progenitors, and the dispatch table will be malformed.
14743 -- We check that the type is limited to handle the anomalous declaration
14744 -- of Limited_Controlled, which is derived from a non-limited type, and
14745 -- which is handled specially elsewhere as well.
14747 elsif Chars (Parent_Subp) = Name_Op_Eq
14748 and then Is_Dispatching_Operation (Parent_Subp)
14749 and then Etype (Parent_Subp) = Standard_Boolean
14750 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14752 Etype (First_Formal (Parent_Subp)) =
14753 Etype (Next_Formal (First_Formal (Parent_Subp)))
14757 -- If parent is hidden, this can be a regular derivation if the
14758 -- parent is immediately visible in a non-instantiating context,
14759 -- or if we are in the private part of an instance. This test
14760 -- should still be refined ???
14762 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14763 -- operation as a non-visible operation in cases where the parent
14764 -- subprogram might not be visible now, but was visible within the
14765 -- original generic, so it would be wrong to make the inherited
14766 -- subprogram non-visible now. (Not clear if this test is fully
14767 -- correct; are there any cases where we should declare the inherited
14768 -- operation as not visible to avoid it being overridden, e.g., when
14769 -- the parent type is a generic actual with private primitives ???)
14771 -- (they should be treated the same as other private inherited
14772 -- subprograms, but it's not clear how to do this cleanly). ???
14774 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14775 and then Is_Immediately_Visible (Parent_Subp)
14776 and then not In_Instance)
14777 or else In_Instance_Not_Visible
14781 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14782 -- overrides an interface primitive because interface primitives
14783 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14785 elsif Ada_Version >= Ada_2005
14786 and then Is_Dispatching_Operation (Parent_Subp)
14787 and then Covers_Some_Interface (Parent_Subp)
14791 -- Otherwise, the type is inheriting a private operation, so enter it
14792 -- with a special name so it can't be overridden.
14795 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14798 Set_Parent (New_Subp, Parent (Derived_Type));
14800 if Present (Actual_Subp) then
14801 Replace_Type (Actual_Subp, New_Subp);
14803 Replace_Type (Parent_Subp, New_Subp);
14806 Conditional_Delay (New_Subp, Parent_Subp);
14808 -- If we are creating a renaming for a primitive operation of an
14809 -- actual of a generic derived type, we must examine the signature
14810 -- of the actual primitive, not that of the generic formal, which for
14811 -- example may be an interface. However the name and initial value
14812 -- of the inherited operation are those of the formal primitive.
14814 Formal := First_Formal (Parent_Subp);
14816 if Present (Actual_Subp) then
14817 Formal_Of_Actual := First_Formal (Actual_Subp);
14819 Formal_Of_Actual := Empty;
14822 while Present (Formal) loop
14823 New_Formal := New_Copy (Formal);
14825 -- Normally we do not go copying parents, but in the case of
14826 -- formals, we need to link up to the declaration (which is the
14827 -- parameter specification), and it is fine to link up to the
14828 -- original formal's parameter specification in this case.
14830 Set_Parent (New_Formal, Parent (Formal));
14831 Append_Entity (New_Formal, New_Subp);
14833 if Present (Formal_Of_Actual) then
14834 Replace_Type (Formal_Of_Actual, New_Formal);
14835 Next_Formal (Formal_Of_Actual);
14837 Replace_Type (Formal, New_Formal);
14840 Next_Formal (Formal);
14843 -- If this derivation corresponds to a tagged generic actual, then
14844 -- primitive operations rename those of the actual. Otherwise the
14845 -- primitive operations rename those of the parent type, If the parent
14846 -- renames an intrinsic operator, so does the new subprogram. We except
14847 -- concatenation, which is always properly typed, and does not get
14848 -- expanded as other intrinsic operations.
14850 if No (Actual_Subp) then
14851 if Is_Intrinsic_Subprogram (Parent_Subp) then
14852 Set_Is_Intrinsic_Subprogram (New_Subp);
14854 if Present (Alias (Parent_Subp))
14855 and then Chars (Parent_Subp) /= Name_Op_Concat
14857 Set_Alias (New_Subp, Alias (Parent_Subp));
14859 Set_Alias (New_Subp, Parent_Subp);
14863 Set_Alias (New_Subp, Parent_Subp);
14867 Set_Alias (New_Subp, Actual_Subp);
14870 -- Inherit the "ghostness" from the parent subprogram
14872 if Is_Ghost_Entity (Alias (New_Subp)) then
14873 Set_Is_Ghost_Entity (New_Subp);
14876 -- Derived subprograms of a tagged type must inherit the convention
14877 -- of the parent subprogram (a requirement of AI-117). Derived
14878 -- subprograms of untagged types simply get convention Ada by default.
14880 -- If the derived type is a tagged generic formal type with unknown
14881 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14883 -- However, if the type is derived from a generic formal, the further
14884 -- inherited subprogram has the convention of the non-generic ancestor.
14885 -- Otherwise there would be no way to override the operation.
14886 -- (This is subject to forthcoming ARG discussions).
14888 if Is_Tagged_Type (Derived_Type) then
14889 if Is_Generic_Type (Derived_Type)
14890 and then Has_Unknown_Discriminants (Derived_Type)
14892 Set_Convention (New_Subp, Convention_Intrinsic);
14895 if Is_Generic_Type (Parent_Type)
14896 and then Has_Unknown_Discriminants (Parent_Type)
14898 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14900 Set_Convention (New_Subp, Convention (Parent_Subp));
14905 -- Predefined controlled operations retain their name even if the parent
14906 -- is hidden (see above), but they are not primitive operations if the
14907 -- ancestor is not visible, for example if the parent is a private
14908 -- extension completed with a controlled extension. Note that a full
14909 -- type that is controlled can break privacy: the flag Is_Controlled is
14910 -- set on both views of the type.
14912 if Is_Controlled (Parent_Type)
14913 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14916 and then Is_Hidden (Parent_Subp)
14917 and then not Is_Visibly_Controlled (Parent_Type)
14919 Set_Is_Hidden (New_Subp);
14922 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14923 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14925 if Ekind (Parent_Subp) = E_Procedure then
14926 Set_Is_Valued_Procedure
14927 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14929 Set_Has_Controlling_Result
14930 (New_Subp, Has_Controlling_Result (Parent_Subp));
14933 -- No_Return must be inherited properly. If this is overridden in the
14934 -- case of a dispatching operation, then a check is made in Sem_Disp
14935 -- that the overriding operation is also No_Return (no such check is
14936 -- required for the case of non-dispatching operation.
14938 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14940 -- A derived function with a controlling result is abstract. If the
14941 -- Derived_Type is a nonabstract formal generic derived type, then
14942 -- inherited operations are not abstract: the required check is done at
14943 -- instantiation time. If the derivation is for a generic actual, the
14944 -- function is not abstract unless the actual is.
14946 if Is_Generic_Type (Derived_Type)
14947 and then not Is_Abstract_Type (Derived_Type)
14951 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14952 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14954 -- A subprogram subject to pragma Extensions_Visible with value False
14955 -- requires overriding if the subprogram has at least one controlling
14956 -- OUT parameter (SPARK RM 6.1.7(6)).
14958 elsif Ada_Version >= Ada_2005
14959 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14960 or else (Is_Tagged_Type (Derived_Type)
14961 and then Etype (New_Subp) = Derived_Type
14962 and then not Is_Null_Extension (Derived_Type))
14963 or else (Is_Tagged_Type (Derived_Type)
14964 and then Ekind (Etype (New_Subp)) =
14965 E_Anonymous_Access_Type
14966 and then Designated_Type (Etype (New_Subp)) =
14968 and then not Is_Null_Extension (Derived_Type))
14969 or else (Comes_From_Source (Alias (New_Subp))
14970 and then Is_EVF_Procedure (Alias (New_Subp))))
14971 and then No (Actual_Subp)
14973 if not Is_Tagged_Type (Derived_Type)
14974 or else Is_Abstract_Type (Derived_Type)
14975 or else Is_Abstract_Subprogram (Alias (New_Subp))
14977 Set_Is_Abstract_Subprogram (New_Subp);
14979 Set_Requires_Overriding (New_Subp);
14982 elsif Ada_Version < Ada_2005
14983 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14984 or else (Is_Tagged_Type (Derived_Type)
14985 and then Etype (New_Subp) = Derived_Type
14986 and then No (Actual_Subp)))
14988 Set_Is_Abstract_Subprogram (New_Subp);
14990 -- AI05-0097 : an inherited operation that dispatches on result is
14991 -- abstract if the derived type is abstract, even if the parent type
14992 -- is concrete and the derived type is a null extension.
14994 elsif Has_Controlling_Result (Alias (New_Subp))
14995 and then Is_Abstract_Type (Etype (New_Subp))
14997 Set_Is_Abstract_Subprogram (New_Subp);
14999 -- Finally, if the parent type is abstract we must verify that all
15000 -- inherited operations are either non-abstract or overridden, or that
15001 -- the derived type itself is abstract (this check is performed at the
15002 -- end of a package declaration, in Check_Abstract_Overriding). A
15003 -- private overriding in the parent type will not be visible in the
15004 -- derivation if we are not in an inner package or in a child unit of
15005 -- the parent type, in which case the abstractness of the inherited
15006 -- operation is carried to the new subprogram.
15008 elsif Is_Abstract_Type (Parent_Type)
15009 and then not In_Open_Scopes (Scope (Parent_Type))
15010 and then Is_Private_Overriding
15011 and then Is_Abstract_Subprogram (Visible_Subp)
15013 if No (Actual_Subp) then
15014 Set_Alias (New_Subp, Visible_Subp);
15015 Set_Is_Abstract_Subprogram (New_Subp, True);
15018 -- If this is a derivation for an instance of a formal derived
15019 -- type, abstractness comes from the primitive operation of the
15020 -- actual, not from the operation inherited from the ancestor.
15022 Set_Is_Abstract_Subprogram
15023 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
15027 New_Overloaded_Entity (New_Subp, Derived_Type);
15029 -- Check for case of a derived subprogram for the instantiation of a
15030 -- formal derived tagged type, if so mark the subprogram as dispatching
15031 -- and inherit the dispatching attributes of the actual subprogram. The
15032 -- derived subprogram is effectively renaming of the actual subprogram,
15033 -- so it needs to have the same attributes as the actual.
15035 if Present (Actual_Subp)
15036 and then Is_Dispatching_Operation (Actual_Subp)
15038 Set_Is_Dispatching_Operation (New_Subp);
15040 if Present (DTC_Entity (Actual_Subp)) then
15041 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
15042 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
15046 -- Indicate that a derived subprogram does not require a body and that
15047 -- it does not require processing of default expressions.
15049 Set_Has_Completion (New_Subp);
15050 Set_Default_Expressions_Processed (New_Subp);
15052 if Ekind (New_Subp) = E_Function then
15053 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
15055 end Derive_Subprogram;
15057 ------------------------
15058 -- Derive_Subprograms --
15059 ------------------------
15061 procedure Derive_Subprograms
15062 (Parent_Type : Entity_Id;
15063 Derived_Type : Entity_Id;
15064 Generic_Actual : Entity_Id := Empty)
15066 Op_List : constant Elist_Id :=
15067 Collect_Primitive_Operations (Parent_Type);
15069 function Check_Derived_Type return Boolean;
15070 -- Check that all the entities derived from Parent_Type are found in
15071 -- the list of primitives of Derived_Type exactly in the same order.
15073 procedure Derive_Interface_Subprogram
15074 (New_Subp : in out Entity_Id;
15076 Actual_Subp : Entity_Id);
15077 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
15078 -- (which is an interface primitive). If Generic_Actual is present then
15079 -- Actual_Subp is the actual subprogram corresponding with the generic
15080 -- subprogram Subp.
15082 function Check_Derived_Type return Boolean is
15086 New_Subp : Entity_Id;
15091 -- Traverse list of entities in the current scope searching for
15092 -- an incomplete type whose full-view is derived type
15094 E := First_Entity (Scope (Derived_Type));
15095 while Present (E) and then E /= Derived_Type loop
15096 if Ekind (E) = E_Incomplete_Type
15097 and then Present (Full_View (E))
15098 and then Full_View (E) = Derived_Type
15100 -- Disable this test if Derived_Type completes an incomplete
15101 -- type because in such case more primitives can be added
15102 -- later to the list of primitives of Derived_Type by routine
15103 -- Process_Incomplete_Dependents
15108 E := Next_Entity (E);
15111 List := Collect_Primitive_Operations (Derived_Type);
15112 Elmt := First_Elmt (List);
15114 Op_Elmt := First_Elmt (Op_List);
15115 while Present (Op_Elmt) loop
15116 Subp := Node (Op_Elmt);
15117 New_Subp := Node (Elmt);
15119 -- At this early stage Derived_Type has no entities with attribute
15120 -- Interface_Alias. In addition, such primitives are always
15121 -- located at the end of the list of primitives of Parent_Type.
15122 -- Therefore, if found we can safely stop processing pending
15125 exit when Present (Interface_Alias (Subp));
15127 -- Handle hidden entities
15129 if not Is_Predefined_Dispatching_Operation (Subp)
15130 and then Is_Hidden (Subp)
15132 if Present (New_Subp)
15133 and then Primitive_Names_Match (Subp, New_Subp)
15139 if not Present (New_Subp)
15140 or else Ekind (Subp) /= Ekind (New_Subp)
15141 or else not Primitive_Names_Match (Subp, New_Subp)
15149 Next_Elmt (Op_Elmt);
15153 end Check_Derived_Type;
15155 ---------------------------------
15156 -- Derive_Interface_Subprogram --
15157 ---------------------------------
15159 procedure Derive_Interface_Subprogram
15160 (New_Subp : in out Entity_Id;
15162 Actual_Subp : Entity_Id)
15164 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15165 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15168 pragma Assert (Is_Interface (Iface_Type));
15171 (New_Subp => New_Subp,
15172 Parent_Subp => Iface_Subp,
15173 Derived_Type => Derived_Type,
15174 Parent_Type => Iface_Type,
15175 Actual_Subp => Actual_Subp);
15177 -- Given that this new interface entity corresponds with a primitive
15178 -- of the parent that was not overridden we must leave it associated
15179 -- with its parent primitive to ensure that it will share the same
15180 -- dispatch table slot when overridden. We must set the Alias to Subp
15181 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15182 -- (in case we inherited Subp from Iface_Type via a nonabstract
15183 -- generic formal type).
15185 if No (Actual_Subp) then
15186 Set_Alias (New_Subp, Subp);
15189 T : Entity_Id := Find_Dispatching_Type (Subp);
15191 while Etype (T) /= T loop
15192 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15193 Set_Is_Abstract_Subprogram (New_Subp, False);
15201 -- For instantiations this is not needed since the previous call to
15202 -- Derive_Subprogram leaves the entity well decorated.
15205 pragma Assert (Alias (New_Subp) = Actual_Subp);
15208 end Derive_Interface_Subprogram;
15212 Alias_Subp : Entity_Id;
15213 Act_List : Elist_Id;
15214 Act_Elmt : Elmt_Id;
15215 Act_Subp : Entity_Id := Empty;
15217 Need_Search : Boolean := False;
15218 New_Subp : Entity_Id := Empty;
15219 Parent_Base : Entity_Id;
15222 -- Start of processing for Derive_Subprograms
15225 if Ekind (Parent_Type) = E_Record_Type_With_Private
15226 and then Has_Discriminants (Parent_Type)
15227 and then Present (Full_View (Parent_Type))
15229 Parent_Base := Full_View (Parent_Type);
15231 Parent_Base := Parent_Type;
15234 if Present (Generic_Actual) then
15235 Act_List := Collect_Primitive_Operations (Generic_Actual);
15236 Act_Elmt := First_Elmt (Act_List);
15238 Act_List := No_Elist;
15239 Act_Elmt := No_Elmt;
15242 -- Derive primitives inherited from the parent. Note that if the generic
15243 -- actual is present, this is not really a type derivation, it is a
15244 -- completion within an instance.
15246 -- Case 1: Derived_Type does not implement interfaces
15248 if not Is_Tagged_Type (Derived_Type)
15249 or else (not Has_Interfaces (Derived_Type)
15250 and then not (Present (Generic_Actual)
15251 and then Has_Interfaces (Generic_Actual)))
15253 Elmt := First_Elmt (Op_List);
15254 while Present (Elmt) loop
15255 Subp := Node (Elmt);
15257 -- Literals are derived earlier in the process of building the
15258 -- derived type, and are skipped here.
15260 if Ekind (Subp) = E_Enumeration_Literal then
15263 -- The actual is a direct descendant and the common primitive
15264 -- operations appear in the same order.
15266 -- If the generic parent type is present, the derived type is an
15267 -- instance of a formal derived type, and within the instance its
15268 -- operations are those of the actual. We derive from the formal
15269 -- type but make the inherited operations aliases of the
15270 -- corresponding operations of the actual.
15273 pragma Assert (No (Node (Act_Elmt))
15274 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15277 (Subp, Node (Act_Elmt),
15278 Skip_Controlling_Formals => True)));
15281 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15283 if Present (Act_Elmt) then
15284 Next_Elmt (Act_Elmt);
15291 -- Case 2: Derived_Type implements interfaces
15294 -- If the parent type has no predefined primitives we remove
15295 -- predefined primitives from the list of primitives of generic
15296 -- actual to simplify the complexity of this algorithm.
15298 if Present (Generic_Actual) then
15300 Has_Predefined_Primitives : Boolean := False;
15303 -- Check if the parent type has predefined primitives
15305 Elmt := First_Elmt (Op_List);
15306 while Present (Elmt) loop
15307 Subp := Node (Elmt);
15309 if Is_Predefined_Dispatching_Operation (Subp)
15310 and then not Comes_From_Source (Ultimate_Alias (Subp))
15312 Has_Predefined_Primitives := True;
15319 -- Remove predefined primitives of Generic_Actual. We must use
15320 -- an auxiliary list because in case of tagged types the value
15321 -- returned by Collect_Primitive_Operations is the value stored
15322 -- in its Primitive_Operations attribute (and we don't want to
15323 -- modify its current contents).
15325 if not Has_Predefined_Primitives then
15327 Aux_List : constant Elist_Id := New_Elmt_List;
15330 Elmt := First_Elmt (Act_List);
15331 while Present (Elmt) loop
15332 Subp := Node (Elmt);
15334 if not Is_Predefined_Dispatching_Operation (Subp)
15335 or else Comes_From_Source (Subp)
15337 Append_Elmt (Subp, Aux_List);
15343 Act_List := Aux_List;
15347 Act_Elmt := First_Elmt (Act_List);
15348 Act_Subp := Node (Act_Elmt);
15352 -- Stage 1: If the generic actual is not present we derive the
15353 -- primitives inherited from the parent type. If the generic parent
15354 -- type is present, the derived type is an instance of a formal
15355 -- derived type, and within the instance its operations are those of
15356 -- the actual. We derive from the formal type but make the inherited
15357 -- operations aliases of the corresponding operations of the actual.
15359 Elmt := First_Elmt (Op_List);
15360 while Present (Elmt) loop
15361 Subp := Node (Elmt);
15362 Alias_Subp := Ultimate_Alias (Subp);
15364 -- Do not derive internal entities of the parent that link
15365 -- interface primitives with their covering primitive. These
15366 -- entities will be added to this type when frozen.
15368 if Present (Interface_Alias (Subp)) then
15372 -- If the generic actual is present find the corresponding
15373 -- operation in the generic actual. If the parent type is a
15374 -- direct ancestor of the derived type then, even if it is an
15375 -- interface, the operations are inherited from the primary
15376 -- dispatch table and are in the proper order. If we detect here
15377 -- that primitives are not in the same order we traverse the list
15378 -- of primitive operations of the actual to find the one that
15379 -- implements the interface primitive.
15383 (Present (Generic_Actual)
15384 and then Present (Act_Subp)
15386 (Primitive_Names_Match (Subp, Act_Subp)
15388 Type_Conformant (Subp, Act_Subp,
15389 Skip_Controlling_Formals => True)))
15391 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15392 Use_Full_View => True));
15394 -- Remember that we need searching for all pending primitives
15396 Need_Search := True;
15398 -- Handle entities associated with interface primitives
15400 if Present (Alias_Subp)
15401 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15402 and then not Is_Predefined_Dispatching_Operation (Subp)
15404 -- Search for the primitive in the homonym chain
15407 Find_Primitive_Covering_Interface
15408 (Tagged_Type => Generic_Actual,
15409 Iface_Prim => Alias_Subp);
15411 -- Previous search may not locate primitives covering
15412 -- interfaces defined in generics units or instantiations.
15413 -- (it fails if the covering primitive has formals whose
15414 -- type is also defined in generics or instantiations).
15415 -- In such case we search in the list of primitives of the
15416 -- generic actual for the internal entity that links the
15417 -- interface primitive and the covering primitive.
15420 and then Is_Generic_Type (Parent_Type)
15422 -- This code has been designed to handle only generic
15423 -- formals that implement interfaces that are defined
15424 -- in a generic unit or instantiation. If this code is
15425 -- needed for other cases we must review it because
15426 -- (given that it relies on Original_Location to locate
15427 -- the primitive of Generic_Actual that covers the
15428 -- interface) it could leave linked through attribute
15429 -- Alias entities of unrelated instantiations).
15433 (Scope (Find_Dispatching_Type (Alias_Subp)))
15435 Instantiation_Depth
15436 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15439 Iface_Prim_Loc : constant Source_Ptr :=
15440 Original_Location (Sloc (Alias_Subp));
15447 First_Elmt (Primitive_Operations (Generic_Actual));
15449 Search : while Present (Elmt) loop
15450 Prim := Node (Elmt);
15452 if Present (Interface_Alias (Prim))
15453 and then Original_Location
15454 (Sloc (Interface_Alias (Prim))) =
15457 Act_Subp := Alias (Prim);
15466 pragma Assert (Present (Act_Subp)
15467 or else Is_Abstract_Type (Generic_Actual)
15468 or else Serious_Errors_Detected > 0);
15470 -- Handle predefined primitives plus the rest of user-defined
15474 Act_Elmt := First_Elmt (Act_List);
15475 while Present (Act_Elmt) loop
15476 Act_Subp := Node (Act_Elmt);
15478 exit when Primitive_Names_Match (Subp, Act_Subp)
15479 and then Type_Conformant
15481 Skip_Controlling_Formals => True)
15482 and then No (Interface_Alias (Act_Subp));
15484 Next_Elmt (Act_Elmt);
15487 if No (Act_Elmt) then
15493 -- Case 1: If the parent is a limited interface then it has the
15494 -- predefined primitives of synchronized interfaces. However, the
15495 -- actual type may be a non-limited type and hence it does not
15496 -- have such primitives.
15498 if Present (Generic_Actual)
15499 and then not Present (Act_Subp)
15500 and then Is_Limited_Interface (Parent_Base)
15501 and then Is_Predefined_Interface_Primitive (Subp)
15505 -- Case 2: Inherit entities associated with interfaces that were
15506 -- not covered by the parent type. We exclude here null interface
15507 -- primitives because they do not need special management.
15509 -- We also exclude interface operations that are renamings. If the
15510 -- subprogram is an explicit renaming of an interface primitive,
15511 -- it is a regular primitive operation, and the presence of its
15512 -- alias is not relevant: it has to be derived like any other
15515 elsif Present (Alias (Subp))
15516 and then Nkind (Unit_Declaration_Node (Subp)) /=
15517 N_Subprogram_Renaming_Declaration
15518 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15520 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15521 and then Null_Present (Parent (Alias_Subp)))
15523 -- If this is an abstract private type then we transfer the
15524 -- derivation of the interface primitive from the partial view
15525 -- to the full view. This is safe because all the interfaces
15526 -- must be visible in the partial view. Done to avoid adding
15527 -- a new interface derivation to the private part of the
15528 -- enclosing package; otherwise this new derivation would be
15529 -- decorated as hidden when the analysis of the enclosing
15530 -- package completes.
15532 if Is_Abstract_Type (Derived_Type)
15533 and then In_Private_Part (Current_Scope)
15534 and then Has_Private_Declaration (Derived_Type)
15537 Partial_View : Entity_Id;
15542 Partial_View := First_Entity (Current_Scope);
15544 exit when No (Partial_View)
15545 or else (Has_Private_Declaration (Partial_View)
15547 Full_View (Partial_View) = Derived_Type);
15549 Next_Entity (Partial_View);
15552 -- If the partial view was not found then the source code
15553 -- has errors and the derivation is not needed.
15555 if Present (Partial_View) then
15557 First_Elmt (Primitive_Operations (Partial_View));
15558 while Present (Elmt) loop
15559 Ent := Node (Elmt);
15561 if Present (Alias (Ent))
15562 and then Ultimate_Alias (Ent) = Alias (Subp)
15565 (Ent, Primitive_Operations (Derived_Type));
15572 -- If the interface primitive was not found in the
15573 -- partial view then this interface primitive was
15574 -- overridden. We add a derivation to activate in
15575 -- Derive_Progenitor_Subprograms the machinery to
15579 Derive_Interface_Subprogram
15580 (New_Subp => New_Subp,
15582 Actual_Subp => Act_Subp);
15587 Derive_Interface_Subprogram
15588 (New_Subp => New_Subp,
15590 Actual_Subp => Act_Subp);
15593 -- Case 3: Common derivation
15597 (New_Subp => New_Subp,
15598 Parent_Subp => Subp,
15599 Derived_Type => Derived_Type,
15600 Parent_Type => Parent_Base,
15601 Actual_Subp => Act_Subp);
15604 -- No need to update Act_Elm if we must search for the
15605 -- corresponding operation in the generic actual
15608 and then Present (Act_Elmt)
15610 Next_Elmt (Act_Elmt);
15611 Act_Subp := Node (Act_Elmt);
15618 -- Inherit additional operations from progenitors. If the derived
15619 -- type is a generic actual, there are not new primitive operations
15620 -- for the type because it has those of the actual, and therefore
15621 -- nothing needs to be done. The renamings generated above are not
15622 -- primitive operations, and their purpose is simply to make the
15623 -- proper operations visible within an instantiation.
15625 if No (Generic_Actual) then
15626 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15630 -- Final check: Direct descendants must have their primitives in the
15631 -- same order. We exclude from this test untagged types and instances
15632 -- of formal derived types. We skip this test if we have already
15633 -- reported serious errors in the sources.
15635 pragma Assert (not Is_Tagged_Type (Derived_Type)
15636 or else Present (Generic_Actual)
15637 or else Serious_Errors_Detected > 0
15638 or else Check_Derived_Type);
15639 end Derive_Subprograms;
15641 --------------------------------
15642 -- Derived_Standard_Character --
15643 --------------------------------
15645 procedure Derived_Standard_Character
15647 Parent_Type : Entity_Id;
15648 Derived_Type : Entity_Id)
15650 Loc : constant Source_Ptr := Sloc (N);
15651 Def : constant Node_Id := Type_Definition (N);
15652 Indic : constant Node_Id := Subtype_Indication (Def);
15653 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15654 Implicit_Base : constant Entity_Id :=
15656 (E_Enumeration_Type, N, Derived_Type, 'B');
15662 Discard_Node (Process_Subtype (Indic, N));
15664 Set_Etype (Implicit_Base, Parent_Base);
15665 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15666 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15668 Set_Is_Character_Type (Implicit_Base, True);
15669 Set_Has_Delayed_Freeze (Implicit_Base);
15671 -- The bounds of the implicit base are the bounds of the parent base.
15672 -- Note that their type is the parent base.
15674 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15675 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15677 Set_Scalar_Range (Implicit_Base,
15680 High_Bound => Hi));
15682 Conditional_Delay (Derived_Type, Parent_Type);
15684 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15685 Set_Etype (Derived_Type, Implicit_Base);
15686 Set_Size_Info (Derived_Type, Parent_Type);
15688 if Unknown_RM_Size (Derived_Type) then
15689 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15692 Set_Is_Character_Type (Derived_Type, True);
15694 if Nkind (Indic) /= N_Subtype_Indication then
15696 -- If no explicit constraint, the bounds are those
15697 -- of the parent type.
15699 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15700 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15701 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15704 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15706 -- Because the implicit base is used in the conversion of the bounds, we
15707 -- have to freeze it now. This is similar to what is done for numeric
15708 -- types, and it equally suspicious, but otherwise a non-static bound
15709 -- will have a reference to an unfrozen type, which is rejected by Gigi
15710 -- (???). This requires specific care for definition of stream
15711 -- attributes. For details, see comments at the end of
15712 -- Build_Derived_Numeric_Type.
15714 Freeze_Before (N, Implicit_Base);
15715 end Derived_Standard_Character;
15717 ------------------------------
15718 -- Derived_Type_Declaration --
15719 ------------------------------
15721 procedure Derived_Type_Declaration
15724 Is_Completion : Boolean)
15726 Parent_Type : Entity_Id;
15728 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15729 -- Check whether the parent type is a generic formal, or derives
15730 -- directly or indirectly from one.
15732 ------------------------
15733 -- Comes_From_Generic --
15734 ------------------------
15736 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15738 if Is_Generic_Type (Typ) then
15741 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15744 elsif Is_Private_Type (Typ)
15745 and then Present (Full_View (Typ))
15746 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15750 elsif Is_Generic_Actual_Type (Typ) then
15756 end Comes_From_Generic;
15760 Def : constant Node_Id := Type_Definition (N);
15761 Iface_Def : Node_Id;
15762 Indic : constant Node_Id := Subtype_Indication (Def);
15763 Extension : constant Node_Id := Record_Extension_Part (Def);
15764 Parent_Node : Node_Id;
15767 -- Start of processing for Derived_Type_Declaration
15770 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15772 -- Ada 2005 (AI-251): In case of interface derivation check that the
15773 -- parent is also an interface.
15775 if Interface_Present (Def) then
15776 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15778 if not Is_Interface (Parent_Type) then
15779 Diagnose_Interface (Indic, Parent_Type);
15782 Parent_Node := Parent (Base_Type (Parent_Type));
15783 Iface_Def := Type_Definition (Parent_Node);
15785 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15786 -- other limited interfaces.
15788 if Limited_Present (Def) then
15789 if Limited_Present (Iface_Def) then
15792 elsif Protected_Present (Iface_Def) then
15794 ("descendant of & must be declared as a protected "
15795 & "interface", N, Parent_Type);
15797 elsif Synchronized_Present (Iface_Def) then
15799 ("descendant of & must be declared as a synchronized "
15800 & "interface", N, Parent_Type);
15802 elsif Task_Present (Iface_Def) then
15804 ("descendant of & must be declared as a task interface",
15809 ("(Ada 2005) limited interface cannot inherit from "
15810 & "non-limited interface", Indic);
15813 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15814 -- from non-limited or limited interfaces.
15816 elsif not Protected_Present (Def)
15817 and then not Synchronized_Present (Def)
15818 and then not Task_Present (Def)
15820 if Limited_Present (Iface_Def) then
15823 elsif Protected_Present (Iface_Def) then
15825 ("descendant of & must be declared as a protected "
15826 & "interface", N, Parent_Type);
15828 elsif Synchronized_Present (Iface_Def) then
15830 ("descendant of & must be declared as a synchronized "
15831 & "interface", N, Parent_Type);
15833 elsif Task_Present (Iface_Def) then
15835 ("descendant of & must be declared as a task interface",
15844 if Is_Tagged_Type (Parent_Type)
15845 and then Is_Concurrent_Type (Parent_Type)
15846 and then not Is_Interface (Parent_Type)
15849 ("parent type of a record extension cannot be a synchronized "
15850 & "tagged type (RM 3.9.1 (3/1))", N);
15851 Set_Etype (T, Any_Type);
15855 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15858 if Is_Tagged_Type (Parent_Type)
15859 and then Is_Non_Empty_List (Interface_List (Def))
15866 Intf := First (Interface_List (Def));
15867 while Present (Intf) loop
15868 T := Find_Type_Of_Subtype_Indic (Intf);
15870 if not Is_Interface (T) then
15871 Diagnose_Interface (Intf, T);
15873 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15874 -- a limited type from having a nonlimited progenitor.
15876 elsif (Limited_Present (Def)
15877 or else (not Is_Interface (Parent_Type)
15878 and then Is_Limited_Type (Parent_Type)))
15879 and then not Is_Limited_Interface (T)
15882 ("progenitor interface& of limited type must be limited",
15891 if Parent_Type = Any_Type
15892 or else Etype (Parent_Type) = Any_Type
15893 or else (Is_Class_Wide_Type (Parent_Type)
15894 and then Etype (Parent_Type) = T)
15896 -- If Parent_Type is undefined or illegal, make new type into a
15897 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15898 -- errors. If this is a self-definition, emit error now.
15900 if T = Parent_Type or else T = Etype (Parent_Type) then
15901 Error_Msg_N ("type cannot be used in its own definition", Indic);
15904 Set_Ekind (T, Ekind (Parent_Type));
15905 Set_Etype (T, Any_Type);
15906 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15908 if Is_Tagged_Type (T)
15909 and then Is_Record_Type (T)
15911 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15917 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15918 -- an interface is special because the list of interfaces in the full
15919 -- view can be given in any order. For example:
15921 -- type A is interface;
15922 -- type B is interface and A;
15923 -- type D is new B with private;
15925 -- type D is new A and B with null record; -- 1 --
15927 -- In this case we perform the following transformation of -1-:
15929 -- type D is new B and A with null record;
15931 -- If the parent of the full-view covers the parent of the partial-view
15932 -- we have two possible cases:
15934 -- 1) They have the same parent
15935 -- 2) The parent of the full-view implements some further interfaces
15937 -- In both cases we do not need to perform the transformation. In the
15938 -- first case the source program is correct and the transformation is
15939 -- not needed; in the second case the source program does not fulfill
15940 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15943 -- This transformation not only simplifies the rest of the analysis of
15944 -- this type declaration but also simplifies the correct generation of
15945 -- the object layout to the expander.
15947 if In_Private_Part (Current_Scope)
15948 and then Is_Interface (Parent_Type)
15952 Partial_View : Entity_Id;
15953 Partial_View_Parent : Entity_Id;
15954 New_Iface : Node_Id;
15957 -- Look for the associated private type declaration
15959 Partial_View := First_Entity (Current_Scope);
15961 exit when No (Partial_View)
15962 or else (Has_Private_Declaration (Partial_View)
15963 and then Full_View (Partial_View) = T);
15965 Next_Entity (Partial_View);
15968 -- If the partial view was not found then the source code has
15969 -- errors and the transformation is not needed.
15971 if Present (Partial_View) then
15972 Partial_View_Parent := Etype (Partial_View);
15974 -- If the parent of the full-view covers the parent of the
15975 -- partial-view we have nothing else to do.
15977 if Interface_Present_In_Ancestor
15978 (Parent_Type, Partial_View_Parent)
15982 -- Traverse the list of interfaces of the full-view to look
15983 -- for the parent of the partial-view and perform the tree
15987 Iface := First (Interface_List (Def));
15988 while Present (Iface) loop
15989 if Etype (Iface) = Etype (Partial_View) then
15990 Rewrite (Subtype_Indication (Def),
15991 New_Copy (Subtype_Indication
15992 (Parent (Partial_View))));
15995 Make_Identifier (Sloc (N), Chars (Parent_Type));
15996 Append (New_Iface, Interface_List (Def));
15998 -- Analyze the transformed code
16000 Derived_Type_Declaration (T, N, Is_Completion);
16011 -- Only composite types other than array types are allowed to have
16014 if Present (Discriminant_Specifications (N)) then
16015 if (Is_Elementary_Type (Parent_Type)
16017 Is_Array_Type (Parent_Type))
16018 and then not Error_Posted (N)
16021 ("elementary or array type cannot have discriminants",
16022 Defining_Identifier (First (Discriminant_Specifications (N))));
16023 Set_Has_Discriminants (T, False);
16025 -- The type is allowed to have discriminants
16028 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
16032 -- In Ada 83, a derived type defined in a package specification cannot
16033 -- be used for further derivation until the end of its visible part.
16034 -- Note that derivation in the private part of the package is allowed.
16036 if Ada_Version = Ada_83
16037 and then Is_Derived_Type (Parent_Type)
16038 and then In_Visible_Part (Scope (Parent_Type))
16040 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
16042 ("(Ada 83): premature use of type for derivation", Indic);
16046 -- Check for early use of incomplete or private type
16048 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
16049 Error_Msg_N ("premature derivation of incomplete type", Indic);
16052 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
16053 and then not Comes_From_Generic (Parent_Type))
16054 or else Has_Private_Component (Parent_Type)
16056 -- The ancestor type of a formal type can be incomplete, in which
16057 -- case only the operations of the partial view are available in the
16058 -- generic. Subsequent checks may be required when the full view is
16059 -- analyzed to verify that a derivation from a tagged type has an
16062 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
16065 elsif No (Underlying_Type (Parent_Type))
16066 or else Has_Private_Component (Parent_Type)
16069 ("premature derivation of derived or private type", Indic);
16071 -- Flag the type itself as being in error, this prevents some
16072 -- nasty problems with subsequent uses of the malformed type.
16074 Set_Error_Posted (T);
16076 -- Check that within the immediate scope of an untagged partial
16077 -- view it's illegal to derive from the partial view if the
16078 -- full view is tagged. (7.3(7))
16080 -- We verify that the Parent_Type is a partial view by checking
16081 -- that it is not a Full_Type_Declaration (i.e. a private type or
16082 -- private extension declaration), to distinguish a partial view
16083 -- from a derivation from a private type which also appears as
16084 -- E_Private_Type. If the parent base type is not declared in an
16085 -- enclosing scope there is no need to check.
16087 elsif Present (Full_View (Parent_Type))
16088 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
16089 and then not Is_Tagged_Type (Parent_Type)
16090 and then Is_Tagged_Type (Full_View (Parent_Type))
16091 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
16094 ("premature derivation from type with tagged full view",
16099 -- Check that form of derivation is appropriate
16101 Taggd := Is_Tagged_Type (Parent_Type);
16103 -- Set the parent type to the class-wide type's specific type in this
16104 -- case to prevent cascading errors
16106 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16107 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16108 Set_Etype (T, Etype (Parent_Type));
16112 if Present (Extension) and then not Taggd then
16114 ("type derived from untagged type cannot have extension", Indic);
16116 elsif No (Extension) and then Taggd then
16118 -- If this declaration is within a private part (or body) of a
16119 -- generic instantiation then the derivation is allowed (the parent
16120 -- type can only appear tagged in this case if it's a generic actual
16121 -- type, since it would otherwise have been rejected in the analysis
16122 -- of the generic template).
16124 if not Is_Generic_Actual_Type (Parent_Type)
16125 or else In_Visible_Part (Scope (Parent_Type))
16127 if Is_Class_Wide_Type (Parent_Type) then
16129 ("parent type must not be a class-wide type", Indic);
16131 -- Use specific type to prevent cascaded errors.
16133 Parent_Type := Etype (Parent_Type);
16137 ("type derived from tagged type must have extension", Indic);
16142 -- AI-443: Synchronized formal derived types require a private
16143 -- extension. There is no point in checking the ancestor type or
16144 -- the progenitors since the construct is wrong to begin with.
16146 if Ada_Version >= Ada_2005
16147 and then Is_Generic_Type (T)
16148 and then Present (Original_Node (N))
16151 Decl : constant Node_Id := Original_Node (N);
16154 if Nkind (Decl) = N_Formal_Type_Declaration
16155 and then Nkind (Formal_Type_Definition (Decl)) =
16156 N_Formal_Derived_Type_Definition
16157 and then Synchronized_Present (Formal_Type_Definition (Decl))
16158 and then No (Extension)
16160 -- Avoid emitting a duplicate error message
16162 and then not Error_Posted (Indic)
16165 ("synchronized derived type must have extension", N);
16170 if Null_Exclusion_Present (Def)
16171 and then not Is_Access_Type (Parent_Type)
16173 Error_Msg_N ("null exclusion can only apply to an access type", N);
16176 -- Avoid deriving parent primitives of underlying record views
16178 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16179 Derive_Subps => not Is_Underlying_Record_View (T));
16181 -- AI-419: The parent type of an explicitly limited derived type must
16182 -- be a limited type or a limited interface.
16184 if Limited_Present (Def) then
16185 Set_Is_Limited_Record (T);
16187 if Is_Interface (T) then
16188 Set_Is_Limited_Interface (T);
16191 if not Is_Limited_Type (Parent_Type)
16193 (not Is_Interface (Parent_Type)
16194 or else not Is_Limited_Interface (Parent_Type))
16196 -- AI05-0096: a derivation in the private part of an instance is
16197 -- legal if the generic formal is untagged limited, and the actual
16200 if Is_Generic_Actual_Type (Parent_Type)
16201 and then In_Private_Part (Current_Scope)
16204 (Generic_Parent_Type (Parent (Parent_Type)))
16210 ("parent type& of limited type must be limited",
16216 -- In SPARK, there are no derived type definitions other than type
16217 -- extensions of tagged record types.
16219 if No (Extension) then
16220 Check_SPARK_05_Restriction
16221 ("derived type is not allowed", Original_Node (N));
16223 end Derived_Type_Declaration;
16225 ------------------------
16226 -- Diagnose_Interface --
16227 ------------------------
16229 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16231 if not Is_Interface (E) and then E /= Any_Type then
16232 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16234 end Diagnose_Interface;
16236 ----------------------------------
16237 -- Enumeration_Type_Declaration --
16238 ----------------------------------
16240 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16247 -- Create identifier node representing lower bound
16249 B_Node := New_Node (N_Identifier, Sloc (Def));
16250 L := First (Literals (Def));
16251 Set_Chars (B_Node, Chars (L));
16252 Set_Entity (B_Node, L);
16253 Set_Etype (B_Node, T);
16254 Set_Is_Static_Expression (B_Node, True);
16256 R_Node := New_Node (N_Range, Sloc (Def));
16257 Set_Low_Bound (R_Node, B_Node);
16259 Set_Ekind (T, E_Enumeration_Type);
16260 Set_First_Literal (T, L);
16262 Set_Is_Constrained (T);
16266 -- Loop through literals of enumeration type setting pos and rep values
16267 -- except that if the Ekind is already set, then it means the literal
16268 -- was already constructed (case of a derived type declaration and we
16269 -- should not disturb the Pos and Rep values.
16271 while Present (L) loop
16272 if Ekind (L) /= E_Enumeration_Literal then
16273 Set_Ekind (L, E_Enumeration_Literal);
16274 Set_Enumeration_Pos (L, Ev);
16275 Set_Enumeration_Rep (L, Ev);
16276 Set_Is_Known_Valid (L, True);
16280 New_Overloaded_Entity (L);
16281 Generate_Definition (L);
16282 Set_Convention (L, Convention_Intrinsic);
16284 -- Case of character literal
16286 if Nkind (L) = N_Defining_Character_Literal then
16287 Set_Is_Character_Type (T, True);
16289 -- Check violation of No_Wide_Characters
16291 if Restriction_Check_Required (No_Wide_Characters) then
16292 Get_Name_String (Chars (L));
16294 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16295 Check_Restriction (No_Wide_Characters, L);
16304 -- Now create a node representing upper bound
16306 B_Node := New_Node (N_Identifier, Sloc (Def));
16307 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16308 Set_Entity (B_Node, Last (Literals (Def)));
16309 Set_Etype (B_Node, T);
16310 Set_Is_Static_Expression (B_Node, True);
16312 Set_High_Bound (R_Node, B_Node);
16314 -- Initialize various fields of the type. Some of this information
16315 -- may be overwritten later through rep.clauses.
16317 Set_Scalar_Range (T, R_Node);
16318 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16319 Set_Enum_Esize (T);
16320 Set_Enum_Pos_To_Rep (T, Empty);
16322 -- Set Discard_Names if configuration pragma set, or if there is
16323 -- a parameterless pragma in the current declarative region
16325 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16326 Set_Discard_Names (T);
16329 -- Process end label if there is one
16331 if Present (Def) then
16332 Process_End_Label (Def, 'e', T);
16334 end Enumeration_Type_Declaration;
16336 ---------------------------------
16337 -- Expand_To_Stored_Constraint --
16338 ---------------------------------
16340 function Expand_To_Stored_Constraint
16342 Constraint : Elist_Id) return Elist_Id
16344 Explicitly_Discriminated_Type : Entity_Id;
16345 Expansion : Elist_Id;
16346 Discriminant : Entity_Id;
16348 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16349 -- Find the nearest type that actually specifies discriminants
16351 ---------------------------------
16352 -- Type_With_Explicit_Discrims --
16353 ---------------------------------
16355 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16356 Typ : constant E := Base_Type (Id);
16359 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16360 if Present (Full_View (Typ)) then
16361 return Type_With_Explicit_Discrims (Full_View (Typ));
16365 if Has_Discriminants (Typ) then
16370 if Etype (Typ) = Typ then
16372 elsif Has_Discriminants (Typ) then
16375 return Type_With_Explicit_Discrims (Etype (Typ));
16378 end Type_With_Explicit_Discrims;
16380 -- Start of processing for Expand_To_Stored_Constraint
16383 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16387 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16389 if No (Explicitly_Discriminated_Type) then
16393 Expansion := New_Elmt_List;
16396 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16397 while Present (Discriminant) loop
16399 (Get_Discriminant_Value
16400 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16402 Next_Stored_Discriminant (Discriminant);
16406 end Expand_To_Stored_Constraint;
16408 ---------------------------
16409 -- Find_Hidden_Interface --
16410 ---------------------------
16412 function Find_Hidden_Interface
16414 Dest : Elist_Id) return Entity_Id
16417 Iface_Elmt : Elmt_Id;
16420 if Present (Src) and then Present (Dest) then
16421 Iface_Elmt := First_Elmt (Src);
16422 while Present (Iface_Elmt) loop
16423 Iface := Node (Iface_Elmt);
16425 if Is_Interface (Iface)
16426 and then not Contain_Interface (Iface, Dest)
16431 Next_Elmt (Iface_Elmt);
16436 end Find_Hidden_Interface;
16438 --------------------
16439 -- Find_Type_Name --
16440 --------------------
16442 function Find_Type_Name (N : Node_Id) return Entity_Id is
16443 Id : constant Entity_Id := Defining_Identifier (N);
16444 New_Id : Entity_Id;
16446 Prev_Par : Node_Id;
16448 procedure Check_Duplicate_Aspects;
16449 -- Check that aspects specified in a completion have not been specified
16450 -- already in the partial view.
16452 procedure Tag_Mismatch;
16453 -- Diagnose a tagged partial view whose full view is untagged. We post
16454 -- the message on the full view, with a reference to the previous
16455 -- partial view. The partial view can be private or incomplete, and
16456 -- these are handled in a different manner, so we determine the position
16457 -- of the error message from the respective slocs of both.
16459 -----------------------------
16460 -- Check_Duplicate_Aspects --
16461 -----------------------------
16463 procedure Check_Duplicate_Aspects is
16464 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id;
16465 -- Return the corresponding aspect of the partial view which matches
16466 -- the aspect id of Asp. Return Empty is no such aspect exists.
16468 -----------------------------
16469 -- Get_Partial_View_Aspect --
16470 -----------------------------
16472 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id is
16473 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp);
16474 Prev_Asps : constant List_Id := Aspect_Specifications (Prev_Par);
16475 Prev_Asp : Node_Id;
16478 if Present (Prev_Asps) then
16479 Prev_Asp := First (Prev_Asps);
16480 while Present (Prev_Asp) loop
16481 if Get_Aspect_Id (Prev_Asp) = Asp_Id then
16490 end Get_Partial_View_Aspect;
16494 Full_Asps : constant List_Id := Aspect_Specifications (N);
16495 Full_Asp : Node_Id;
16496 Part_Asp : Node_Id;
16498 -- Start of processing for Check_Duplicate_Aspects
16501 if Present (Full_Asps) then
16502 Full_Asp := First (Full_Asps);
16503 while Present (Full_Asp) loop
16504 Part_Asp := Get_Partial_View_Aspect (Full_Asp);
16506 -- An aspect and its class-wide counterpart are two distinct
16507 -- aspects and may apply to both views of an entity.
16509 if Present (Part_Asp)
16510 and then Class_Present (Part_Asp) = Class_Present (Full_Asp)
16513 ("aspect already specified in private declaration",
16520 if Has_Discriminants (Prev)
16521 and then not Has_Unknown_Discriminants (Prev)
16522 and then Get_Aspect_Id (Full_Asp) =
16523 Aspect_Implicit_Dereference
16526 ("cannot specify aspect if partial view has known "
16527 & "discriminants", Full_Asp);
16533 end Check_Duplicate_Aspects;
16539 procedure Tag_Mismatch is
16541 if Sloc (Prev) < Sloc (Id) then
16542 if Ada_Version >= Ada_2012
16543 and then Nkind (N) = N_Private_Type_Declaration
16546 ("declaration of private } must be a tagged type ", Id, Prev);
16549 ("full declaration of } must be a tagged type ", Id, Prev);
16553 if Ada_Version >= Ada_2012
16554 and then Nkind (N) = N_Private_Type_Declaration
16557 ("declaration of private } must be a tagged type ", Prev, Id);
16560 ("full declaration of } must be a tagged type ", Prev, Id);
16565 -- Start of processing for Find_Type_Name
16568 -- Find incomplete declaration, if one was given
16570 Prev := Current_Entity_In_Scope (Id);
16572 -- New type declaration
16578 -- Previous declaration exists
16581 Prev_Par := Parent (Prev);
16583 -- Error if not incomplete/private case except if previous
16584 -- declaration is implicit, etc. Enter_Name will emit error if
16587 if not Is_Incomplete_Or_Private_Type (Prev) then
16591 -- Check invalid completion of private or incomplete type
16593 elsif not Nkind_In (N, N_Full_Type_Declaration,
16594 N_Task_Type_Declaration,
16595 N_Protected_Type_Declaration)
16597 (Ada_Version < Ada_2012
16598 or else not Is_Incomplete_Type (Prev)
16599 or else not Nkind_In (N, N_Private_Type_Declaration,
16600 N_Private_Extension_Declaration))
16602 -- Completion must be a full type declarations (RM 7.3(4))
16604 Error_Msg_Sloc := Sloc (Prev);
16605 Error_Msg_NE ("invalid completion of }", Id, Prev);
16607 -- Set scope of Id to avoid cascaded errors. Entity is never
16608 -- examined again, except when saving globals in generics.
16610 Set_Scope (Id, Current_Scope);
16613 -- If this is a repeated incomplete declaration, no further
16614 -- checks are possible.
16616 if Nkind (N) = N_Incomplete_Type_Declaration then
16620 -- Case of full declaration of incomplete type
16622 elsif Ekind (Prev) = E_Incomplete_Type
16623 and then (Ada_Version < Ada_2012
16624 or else No (Full_View (Prev))
16625 or else not Is_Private_Type (Full_View (Prev)))
16627 -- Indicate that the incomplete declaration has a matching full
16628 -- declaration. The defining occurrence of the incomplete
16629 -- declaration remains the visible one, and the procedure
16630 -- Get_Full_View dereferences it whenever the type is used.
16632 if Present (Full_View (Prev)) then
16633 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16636 Set_Full_View (Prev, Id);
16637 Append_Entity (Id, Current_Scope);
16638 Set_Is_Public (Id, Is_Public (Prev));
16639 Set_Is_Internal (Id);
16642 -- If the incomplete view is tagged, a class_wide type has been
16643 -- created already. Use it for the private type as well, in order
16644 -- to prevent multiple incompatible class-wide types that may be
16645 -- created for self-referential anonymous access components.
16647 if Is_Tagged_Type (Prev)
16648 and then Present (Class_Wide_Type (Prev))
16650 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16651 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16653 -- The type of the classwide type is the current Id. Previously
16654 -- this was not done for private declarations because of order-
16655 -- of elaboration issues in the back-end, but gigi now handles
16658 Set_Etype (Class_Wide_Type (Id), Id);
16661 -- Case of full declaration of private type
16664 -- If the private type was a completion of an incomplete type then
16665 -- update Prev to reference the private type
16667 if Ada_Version >= Ada_2012
16668 and then Ekind (Prev) = E_Incomplete_Type
16669 and then Present (Full_View (Prev))
16670 and then Is_Private_Type (Full_View (Prev))
16672 Prev := Full_View (Prev);
16673 Prev_Par := Parent (Prev);
16676 if Nkind (N) = N_Full_Type_Declaration
16678 (Type_Definition (N), N_Record_Definition,
16679 N_Derived_Type_Definition)
16680 and then Interface_Present (Type_Definition (N))
16683 ("completion of private type cannot be an interface", N);
16686 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16687 if Etype (Prev) /= Prev then
16689 -- Prev is a private subtype or a derived type, and needs
16692 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16695 elsif Ekind (Prev) = E_Private_Type
16696 and then Nkind_In (N, N_Task_Type_Declaration,
16697 N_Protected_Type_Declaration)
16700 ("completion of nonlimited type cannot be limited", N);
16702 elsif Ekind (Prev) = E_Record_Type_With_Private
16703 and then Nkind_In (N, N_Task_Type_Declaration,
16704 N_Protected_Type_Declaration)
16706 if not Is_Limited_Record (Prev) then
16708 ("completion of nonlimited type cannot be limited", N);
16710 elsif No (Interface_List (N)) then
16712 ("completion of tagged private type must be tagged",
16717 -- Ada 2005 (AI-251): Private extension declaration of a task
16718 -- type or a protected type. This case arises when covering
16719 -- interface types.
16721 elsif Nkind_In (N, N_Task_Type_Declaration,
16722 N_Protected_Type_Declaration)
16726 elsif Nkind (N) /= N_Full_Type_Declaration
16727 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16730 ("full view of private extension must be an extension", N);
16732 elsif not (Abstract_Present (Parent (Prev)))
16733 and then Abstract_Present (Type_Definition (N))
16736 ("full view of non-abstract extension cannot be abstract", N);
16739 if not In_Private_Part (Current_Scope) then
16741 ("declaration of full view must appear in private part", N);
16744 if Ada_Version >= Ada_2012 then
16745 Check_Duplicate_Aspects;
16748 Copy_And_Swap (Prev, Id);
16749 Set_Has_Private_Declaration (Prev);
16750 Set_Has_Private_Declaration (Id);
16752 -- AI12-0133: Indicate whether we have a partial view with
16753 -- unknown discriminants, in which case initialization of objects
16754 -- of the type do not receive an invariant check.
16756 Set_Partial_View_Has_Unknown_Discr
16757 (Prev, Has_Unknown_Discriminants (Id));
16759 -- Preserve aspect and iterator flags that may have been set on
16760 -- the partial view.
16762 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16763 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16765 -- If no error, propagate freeze_node from private to full view.
16766 -- It may have been generated for an early operational item.
16768 if Present (Freeze_Node (Id))
16769 and then Serious_Errors_Detected = 0
16770 and then No (Full_View (Id))
16772 Set_Freeze_Node (Prev, Freeze_Node (Id));
16773 Set_Freeze_Node (Id, Empty);
16774 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16777 Set_Full_View (Id, Prev);
16781 -- Verify that full declaration conforms to partial one
16783 if Is_Incomplete_Or_Private_Type (Prev)
16784 and then Present (Discriminant_Specifications (Prev_Par))
16786 if Present (Discriminant_Specifications (N)) then
16787 if Ekind (Prev) = E_Incomplete_Type then
16788 Check_Discriminant_Conformance (N, Prev, Prev);
16790 Check_Discriminant_Conformance (N, Prev, Id);
16795 ("missing discriminants in full type declaration", N);
16797 -- To avoid cascaded errors on subsequent use, share the
16798 -- discriminants of the partial view.
16800 Set_Discriminant_Specifications (N,
16801 Discriminant_Specifications (Prev_Par));
16805 -- A prior untagged partial view can have an associated class-wide
16806 -- type due to use of the class attribute, and in this case the full
16807 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16808 -- of incomplete tagged declarations, but we check for it.
16811 and then (Is_Tagged_Type (Prev)
16812 or else Present (Class_Wide_Type (Prev)))
16814 -- Ada 2012 (AI05-0162): A private type may be the completion of
16815 -- an incomplete type.
16817 if Ada_Version >= Ada_2012
16818 and then Is_Incomplete_Type (Prev)
16819 and then Nkind_In (N, N_Private_Type_Declaration,
16820 N_Private_Extension_Declaration)
16822 -- No need to check private extensions since they are tagged
16824 if Nkind (N) = N_Private_Type_Declaration
16825 and then not Tagged_Present (N)
16830 -- The full declaration is either a tagged type (including
16831 -- a synchronized type that implements interfaces) or a
16832 -- type extension, otherwise this is an error.
16834 elsif Nkind_In (N, N_Task_Type_Declaration,
16835 N_Protected_Type_Declaration)
16837 if No (Interface_List (N)) and then not Error_Posted (N) then
16841 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16843 -- Indicate that the previous declaration (tagged incomplete
16844 -- or private declaration) requires the same on the full one.
16846 if not Tagged_Present (Type_Definition (N)) then
16848 Set_Is_Tagged_Type (Id);
16851 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16852 if No (Record_Extension_Part (Type_Definition (N))) then
16854 ("full declaration of } must be a record extension",
16857 -- Set some attributes to produce a usable full view
16859 Set_Is_Tagged_Type (Id);
16868 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16869 and then Present (Premature_Use (Parent (Prev)))
16871 Error_Msg_Sloc := Sloc (N);
16873 ("\full declaration #", Premature_Use (Parent (Prev)));
16878 end Find_Type_Name;
16880 -------------------------
16881 -- Find_Type_Of_Object --
16882 -------------------------
16884 function Find_Type_Of_Object
16885 (Obj_Def : Node_Id;
16886 Related_Nod : Node_Id) return Entity_Id
16888 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16889 P : Node_Id := Parent (Obj_Def);
16894 -- If the parent is a component_definition node we climb to the
16895 -- component_declaration node
16897 if Nkind (P) = N_Component_Definition then
16901 -- Case of an anonymous array subtype
16903 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16904 N_Unconstrained_Array_Definition)
16907 Array_Type_Declaration (T, Obj_Def);
16909 -- Create an explicit subtype whenever possible
16911 elsif Nkind (P) /= N_Component_Declaration
16912 and then Def_Kind = N_Subtype_Indication
16914 -- Base name of subtype on object name, which will be unique in
16915 -- the current scope.
16917 -- If this is a duplicate declaration, return base type, to avoid
16918 -- generating duplicate anonymous types.
16920 if Error_Posted (P) then
16921 Analyze (Subtype_Mark (Obj_Def));
16922 return Entity (Subtype_Mark (Obj_Def));
16927 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16929 T := Make_Defining_Identifier (Sloc (P), Nam);
16931 Insert_Action (Obj_Def,
16932 Make_Subtype_Declaration (Sloc (P),
16933 Defining_Identifier => T,
16934 Subtype_Indication => Relocate_Node (Obj_Def)));
16936 -- This subtype may need freezing, and this will not be done
16937 -- automatically if the object declaration is not in declarative
16938 -- part. Since this is an object declaration, the type cannot always
16939 -- be frozen here. Deferred constants do not freeze their type
16940 -- (which often enough will be private).
16942 if Nkind (P) = N_Object_Declaration
16943 and then Constant_Present (P)
16944 and then No (Expression (P))
16948 -- Here we freeze the base type of object type to catch premature use
16949 -- of discriminated private type without a full view.
16952 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16955 -- Ada 2005 AI-406: the object definition in an object declaration
16956 -- can be an access definition.
16958 elsif Def_Kind = N_Access_Definition then
16959 T := Access_Definition (Related_Nod, Obj_Def);
16961 Set_Is_Local_Anonymous_Access
16963 V => (Ada_Version < Ada_2012)
16964 or else (Nkind (P) /= N_Object_Declaration)
16965 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16967 -- Otherwise, the object definition is just a subtype_mark
16970 T := Process_Subtype (Obj_Def, Related_Nod);
16972 -- If expansion is disabled an object definition that is an aggregate
16973 -- will not get expanded and may lead to scoping problems in the back
16974 -- end, if the object is referenced in an inner scope. In that case
16975 -- create an itype reference for the object definition now. This
16976 -- may be redundant in some cases, but harmless.
16979 and then Nkind (Related_Nod) = N_Object_Declaration
16982 Build_Itype_Reference (T, Related_Nod);
16987 end Find_Type_Of_Object;
16989 --------------------------------
16990 -- Find_Type_Of_Subtype_Indic --
16991 --------------------------------
16993 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16997 -- Case of subtype mark with a constraint
16999 if Nkind (S) = N_Subtype_Indication then
17000 Find_Type (Subtype_Mark (S));
17001 Typ := Entity (Subtype_Mark (S));
17004 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
17007 ("incorrect constraint for this kind of type", Constraint (S));
17008 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17011 -- Otherwise we have a subtype mark without a constraint
17013 elsif Error_Posted (S) then
17014 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
17022 -- Check No_Wide_Characters restriction
17024 Check_Wide_Character_Restriction (Typ, S);
17027 end Find_Type_Of_Subtype_Indic;
17029 -------------------------------------
17030 -- Floating_Point_Type_Declaration --
17031 -------------------------------------
17033 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17034 Digs : constant Node_Id := Digits_Expression (Def);
17035 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
17037 Base_Typ : Entity_Id;
17038 Implicit_Base : Entity_Id;
17041 function Can_Derive_From (E : Entity_Id) return Boolean;
17042 -- Find if given digits value, and possibly a specified range, allows
17043 -- derivation from specified type
17045 function Find_Base_Type return Entity_Id;
17046 -- Find a predefined base type that Def can derive from, or generate
17047 -- an error and substitute Long_Long_Float if none exists.
17049 ---------------------
17050 -- Can_Derive_From --
17051 ---------------------
17053 function Can_Derive_From (E : Entity_Id) return Boolean is
17054 Spec : constant Entity_Id := Real_Range_Specification (Def);
17057 -- Check specified "digits" constraint
17059 if Digs_Val > Digits_Value (E) then
17063 -- Check for matching range, if specified
17065 if Present (Spec) then
17066 if Expr_Value_R (Type_Low_Bound (E)) >
17067 Expr_Value_R (Low_Bound (Spec))
17072 if Expr_Value_R (Type_High_Bound (E)) <
17073 Expr_Value_R (High_Bound (Spec))
17080 end Can_Derive_From;
17082 --------------------
17083 -- Find_Base_Type --
17084 --------------------
17086 function Find_Base_Type return Entity_Id is
17087 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
17090 -- Iterate over the predefined types in order, returning the first
17091 -- one that Def can derive from.
17093 while Present (Choice) loop
17094 if Can_Derive_From (Node (Choice)) then
17095 return Node (Choice);
17098 Next_Elmt (Choice);
17101 -- If we can't derive from any existing type, use Long_Long_Float
17102 -- and give appropriate message explaining the problem.
17104 if Digs_Val > Max_Digs_Val then
17105 -- It might be the case that there is a type with the requested
17106 -- range, just not the combination of digits and range.
17109 ("no predefined type has requested range and precision",
17110 Real_Range_Specification (Def));
17114 ("range too large for any predefined type",
17115 Real_Range_Specification (Def));
17118 return Standard_Long_Long_Float;
17119 end Find_Base_Type;
17121 -- Start of processing for Floating_Point_Type_Declaration
17124 Check_Restriction (No_Floating_Point, Def);
17126 -- Create an implicit base type
17129 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
17131 -- Analyze and verify digits value
17133 Analyze_And_Resolve (Digs, Any_Integer);
17134 Check_Digits_Expression (Digs);
17135 Digs_Val := Expr_Value (Digs);
17137 -- Process possible range spec and find correct type to derive from
17139 Process_Real_Range_Specification (Def);
17141 -- Check that requested number of digits is not too high.
17143 if Digs_Val > Max_Digs_Val then
17145 -- The check for Max_Base_Digits may be somewhat expensive, as it
17146 -- requires reading System, so only do it when necessary.
17149 Max_Base_Digits : constant Uint :=
17152 (Parent (RTE (RE_Max_Base_Digits))));
17155 if Digs_Val > Max_Base_Digits then
17156 Error_Msg_Uint_1 := Max_Base_Digits;
17157 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17159 elsif No (Real_Range_Specification (Def)) then
17160 Error_Msg_Uint_1 := Max_Digs_Val;
17161 Error_Msg_N ("types with more than ^ digits need range spec "
17162 & "(RM 3.5.7(6))", Digs);
17167 -- Find a suitable type to derive from or complain and use a substitute
17169 Base_Typ := Find_Base_Type;
17171 -- If there are bounds given in the declaration use them as the bounds
17172 -- of the type, otherwise use the bounds of the predefined base type
17173 -- that was chosen based on the Digits value.
17175 if Present (Real_Range_Specification (Def)) then
17176 Set_Scalar_Range (T, Real_Range_Specification (Def));
17177 Set_Is_Constrained (T);
17179 -- The bounds of this range must be converted to machine numbers
17180 -- in accordance with RM 4.9(38).
17182 Bound := Type_Low_Bound (T);
17184 if Nkind (Bound) = N_Real_Literal then
17186 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17187 Set_Is_Machine_Number (Bound);
17190 Bound := Type_High_Bound (T);
17192 if Nkind (Bound) = N_Real_Literal then
17194 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17195 Set_Is_Machine_Number (Bound);
17199 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17202 -- Complete definition of implicit base and declared first subtype. The
17203 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17204 -- are not clobbered when the floating point type acts as a full view of
17207 Set_Etype (Implicit_Base, Base_Typ);
17208 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17209 Set_Size_Info (Implicit_Base, Base_Typ);
17210 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17211 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17212 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17213 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17215 Set_Ekind (T, E_Floating_Point_Subtype);
17216 Set_Etype (T, Implicit_Base);
17217 Set_Size_Info (T, Implicit_Base);
17218 Set_RM_Size (T, RM_Size (Implicit_Base));
17219 Inherit_Rep_Item_Chain (T, Implicit_Base);
17220 Set_Digits_Value (T, Digs_Val);
17221 end Floating_Point_Type_Declaration;
17223 ----------------------------
17224 -- Get_Discriminant_Value --
17225 ----------------------------
17227 -- This is the situation:
17229 -- There is a non-derived type
17231 -- type T0 (Dx, Dy, Dz...)
17233 -- There are zero or more levels of derivation, with each derivation
17234 -- either purely inheriting the discriminants, or defining its own.
17236 -- type Ti is new Ti-1
17238 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17240 -- subtype Ti is ...
17242 -- The subtype issue is avoided by the use of Original_Record_Component,
17243 -- and the fact that derived subtypes also derive the constraints.
17245 -- This chain leads back from
17247 -- Typ_For_Constraint
17249 -- Typ_For_Constraint has discriminants, and the value for each
17250 -- discriminant is given by its corresponding Elmt of Constraints.
17252 -- Discriminant is some discriminant in this hierarchy
17254 -- We need to return its value
17256 -- We do this by recursively searching each level, and looking for
17257 -- Discriminant. Once we get to the bottom, we start backing up
17258 -- returning the value for it which may in turn be a discriminant
17259 -- further up, so on the backup we continue the substitution.
17261 function Get_Discriminant_Value
17262 (Discriminant : Entity_Id;
17263 Typ_For_Constraint : Entity_Id;
17264 Constraint : Elist_Id) return Node_Id
17266 function Root_Corresponding_Discriminant
17267 (Discr : Entity_Id) return Entity_Id;
17268 -- Given a discriminant, traverse the chain of inherited discriminants
17269 -- and return the topmost discriminant.
17271 function Search_Derivation_Levels
17273 Discrim_Values : Elist_Id;
17274 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17275 -- This is the routine that performs the recursive search of levels
17276 -- as described above.
17278 -------------------------------------
17279 -- Root_Corresponding_Discriminant --
17280 -------------------------------------
17282 function Root_Corresponding_Discriminant
17283 (Discr : Entity_Id) return Entity_Id
17289 while Present (Corresponding_Discriminant (D)) loop
17290 D := Corresponding_Discriminant (D);
17294 end Root_Corresponding_Discriminant;
17296 ------------------------------
17297 -- Search_Derivation_Levels --
17298 ------------------------------
17300 function Search_Derivation_Levels
17302 Discrim_Values : Elist_Id;
17303 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17307 Result : Node_Or_Entity_Id;
17308 Result_Entity : Node_Id;
17311 -- If inappropriate type, return Error, this happens only in
17312 -- cascaded error situations, and we want to avoid a blow up.
17314 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17318 -- Look deeper if possible. Use Stored_Constraints only for
17319 -- untagged types. For tagged types use the given constraint.
17320 -- This asymmetry needs explanation???
17322 if not Stored_Discrim_Values
17323 and then Present (Stored_Constraint (Ti))
17324 and then not Is_Tagged_Type (Ti)
17327 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17330 Td : constant Entity_Id := Etype (Ti);
17334 Result := Discriminant;
17337 if Present (Stored_Constraint (Ti)) then
17339 Search_Derivation_Levels
17340 (Td, Stored_Constraint (Ti), True);
17343 Search_Derivation_Levels
17344 (Td, Discrim_Values, Stored_Discrim_Values);
17350 -- Extra underlying places to search, if not found above. For
17351 -- concurrent types, the relevant discriminant appears in the
17352 -- corresponding record. For a type derived from a private type
17353 -- without discriminant, the full view inherits the discriminants
17354 -- of the full view of the parent.
17356 if Result = Discriminant then
17357 if Is_Concurrent_Type (Ti)
17358 and then Present (Corresponding_Record_Type (Ti))
17361 Search_Derivation_Levels (
17362 Corresponding_Record_Type (Ti),
17364 Stored_Discrim_Values);
17366 elsif Is_Private_Type (Ti)
17367 and then not Has_Discriminants (Ti)
17368 and then Present (Full_View (Ti))
17369 and then Etype (Full_View (Ti)) /= Ti
17372 Search_Derivation_Levels (
17375 Stored_Discrim_Values);
17379 -- If Result is not a (reference to a) discriminant, return it,
17380 -- otherwise set Result_Entity to the discriminant.
17382 if Nkind (Result) = N_Defining_Identifier then
17383 pragma Assert (Result = Discriminant);
17384 Result_Entity := Result;
17387 if not Denotes_Discriminant (Result) then
17391 Result_Entity := Entity (Result);
17394 -- See if this level of derivation actually has discriminants because
17395 -- tagged derivations can add them, hence the lower levels need not
17398 if not Has_Discriminants (Ti) then
17402 -- Scan Ti's discriminants for Result_Entity, and return its
17403 -- corresponding value, if any.
17405 Result_Entity := Original_Record_Component (Result_Entity);
17407 Assoc := First_Elmt (Discrim_Values);
17409 if Stored_Discrim_Values then
17410 Disc := First_Stored_Discriminant (Ti);
17412 Disc := First_Discriminant (Ti);
17415 while Present (Disc) loop
17416 pragma Assert (Present (Assoc));
17418 if Original_Record_Component (Disc) = Result_Entity then
17419 return Node (Assoc);
17424 if Stored_Discrim_Values then
17425 Next_Stored_Discriminant (Disc);
17427 Next_Discriminant (Disc);
17431 -- Could not find it
17434 end Search_Derivation_Levels;
17438 Result : Node_Or_Entity_Id;
17440 -- Start of processing for Get_Discriminant_Value
17443 -- ??? This routine is a gigantic mess and will be deleted. For the
17444 -- time being just test for the trivial case before calling recurse.
17446 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17452 D := First_Discriminant (Typ_For_Constraint);
17453 E := First_Elmt (Constraint);
17454 while Present (D) loop
17455 if Chars (D) = Chars (Discriminant) then
17459 Next_Discriminant (D);
17465 Result := Search_Derivation_Levels
17466 (Typ_For_Constraint, Constraint, False);
17468 -- ??? hack to disappear when this routine is gone
17470 if Nkind (Result) = N_Defining_Identifier then
17476 D := First_Discriminant (Typ_For_Constraint);
17477 E := First_Elmt (Constraint);
17478 while Present (D) loop
17479 if Root_Corresponding_Discriminant (D) = Discriminant then
17483 Next_Discriminant (D);
17489 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17491 end Get_Discriminant_Value;
17493 --------------------------
17494 -- Has_Range_Constraint --
17495 --------------------------
17497 function Has_Range_Constraint (N : Node_Id) return Boolean is
17498 C : constant Node_Id := Constraint (N);
17501 if Nkind (C) = N_Range_Constraint then
17504 elsif Nkind (C) = N_Digits_Constraint then
17506 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17507 or else Present (Range_Constraint (C));
17509 elsif Nkind (C) = N_Delta_Constraint then
17510 return Present (Range_Constraint (C));
17515 end Has_Range_Constraint;
17517 ------------------------
17518 -- Inherit_Components --
17519 ------------------------
17521 function Inherit_Components
17523 Parent_Base : Entity_Id;
17524 Derived_Base : Entity_Id;
17525 Is_Tagged : Boolean;
17526 Inherit_Discr : Boolean;
17527 Discs : Elist_Id) return Elist_Id
17529 Assoc_List : constant Elist_Id := New_Elmt_List;
17531 procedure Inherit_Component
17532 (Old_C : Entity_Id;
17533 Plain_Discrim : Boolean := False;
17534 Stored_Discrim : Boolean := False);
17535 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17536 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17537 -- True, Old_C is a stored discriminant. If they are both false then
17538 -- Old_C is a regular component.
17540 -----------------------
17541 -- Inherit_Component --
17542 -----------------------
17544 procedure Inherit_Component
17545 (Old_C : Entity_Id;
17546 Plain_Discrim : Boolean := False;
17547 Stored_Discrim : Boolean := False)
17549 procedure Set_Anonymous_Type (Id : Entity_Id);
17550 -- Id denotes the entity of an access discriminant or anonymous
17551 -- access component. Set the type of Id to either the same type of
17552 -- Old_C or create a new one depending on whether the parent and
17553 -- the child types are in the same scope.
17555 ------------------------
17556 -- Set_Anonymous_Type --
17557 ------------------------
17559 procedure Set_Anonymous_Type (Id : Entity_Id) is
17560 Old_Typ : constant Entity_Id := Etype (Old_C);
17563 if Scope (Parent_Base) = Scope (Derived_Base) then
17564 Set_Etype (Id, Old_Typ);
17566 -- The parent and the derived type are in two different scopes.
17567 -- Reuse the type of the original discriminant / component by
17568 -- copying it in order to preserve all attributes.
17572 Typ : constant Entity_Id := New_Copy (Old_Typ);
17575 Set_Etype (Id, Typ);
17577 -- Since we do not generate component declarations for
17578 -- inherited components, associate the itype with the
17581 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17582 Set_Scope (Typ, Derived_Base);
17585 end Set_Anonymous_Type;
17587 -- Local variables and constants
17589 New_C : constant Entity_Id := New_Copy (Old_C);
17591 Corr_Discrim : Entity_Id;
17592 Discrim : Entity_Id;
17594 -- Start of processing for Inherit_Component
17597 pragma Assert (not Is_Tagged or not Stored_Discrim);
17599 Set_Parent (New_C, Parent (Old_C));
17601 -- Regular discriminants and components must be inserted in the scope
17602 -- of the Derived_Base. Do it here.
17604 if not Stored_Discrim then
17605 Enter_Name (New_C);
17608 -- For tagged types the Original_Record_Component must point to
17609 -- whatever this field was pointing to in the parent type. This has
17610 -- already been achieved by the call to New_Copy above.
17612 if not Is_Tagged then
17613 Set_Original_Record_Component (New_C, New_C);
17616 -- Set the proper type of an access discriminant
17618 if Ekind (New_C) = E_Discriminant
17619 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17621 Set_Anonymous_Type (New_C);
17624 -- If we have inherited a component then see if its Etype contains
17625 -- references to Parent_Base discriminants. In this case, replace
17626 -- these references with the constraints given in Discs. We do not
17627 -- do this for the partial view of private types because this is
17628 -- not needed (only the components of the full view will be used
17629 -- for code generation) and cause problem. We also avoid this
17630 -- transformation in some error situations.
17632 if Ekind (New_C) = E_Component then
17634 -- Set the proper type of an anonymous access component
17636 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17637 Set_Anonymous_Type (New_C);
17639 elsif (Is_Private_Type (Derived_Base)
17640 and then not Is_Generic_Type (Derived_Base))
17641 or else (Is_Empty_Elmt_List (Discs)
17642 and then not Expander_Active)
17644 Set_Etype (New_C, Etype (Old_C));
17647 -- The current component introduces a circularity of the
17650 -- limited with Pack_2;
17651 -- package Pack_1 is
17652 -- type T_1 is tagged record
17653 -- Comp : access Pack_2.T_2;
17659 -- package Pack_2 is
17660 -- type T_2 is new Pack_1.T_1 with ...;
17665 Constrain_Component_Type
17666 (Old_C, Derived_Base, N, Parent_Base, Discs));
17670 -- In derived tagged types it is illegal to reference a non
17671 -- discriminant component in the parent type. To catch this, mark
17672 -- these components with an Ekind of E_Void. This will be reset in
17673 -- Record_Type_Definition after processing the record extension of
17674 -- the derived type.
17676 -- If the declaration is a private extension, there is no further
17677 -- record extension to process, and the components retain their
17678 -- current kind, because they are visible at this point.
17680 if Is_Tagged and then Ekind (New_C) = E_Component
17681 and then Nkind (N) /= N_Private_Extension_Declaration
17683 Set_Ekind (New_C, E_Void);
17686 if Plain_Discrim then
17687 Set_Corresponding_Discriminant (New_C, Old_C);
17688 Build_Discriminal (New_C);
17690 -- If we are explicitly inheriting a stored discriminant it will be
17691 -- completely hidden.
17693 elsif Stored_Discrim then
17694 Set_Corresponding_Discriminant (New_C, Empty);
17695 Set_Discriminal (New_C, Empty);
17696 Set_Is_Completely_Hidden (New_C);
17698 -- Set the Original_Record_Component of each discriminant in the
17699 -- derived base to point to the corresponding stored that we just
17702 Discrim := First_Discriminant (Derived_Base);
17703 while Present (Discrim) loop
17704 Corr_Discrim := Corresponding_Discriminant (Discrim);
17706 -- Corr_Discrim could be missing in an error situation
17708 if Present (Corr_Discrim)
17709 and then Original_Record_Component (Corr_Discrim) = Old_C
17711 Set_Original_Record_Component (Discrim, New_C);
17714 Next_Discriminant (Discrim);
17717 Append_Entity (New_C, Derived_Base);
17720 if not Is_Tagged then
17721 Append_Elmt (Old_C, Assoc_List);
17722 Append_Elmt (New_C, Assoc_List);
17724 end Inherit_Component;
17726 -- Variables local to Inherit_Component
17728 Loc : constant Source_Ptr := Sloc (N);
17730 Parent_Discrim : Entity_Id;
17731 Stored_Discrim : Entity_Id;
17733 Component : Entity_Id;
17735 -- Start of processing for Inherit_Components
17738 if not Is_Tagged then
17739 Append_Elmt (Parent_Base, Assoc_List);
17740 Append_Elmt (Derived_Base, Assoc_List);
17743 -- Inherit parent discriminants if needed
17745 if Inherit_Discr then
17746 Parent_Discrim := First_Discriminant (Parent_Base);
17747 while Present (Parent_Discrim) loop
17748 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17749 Next_Discriminant (Parent_Discrim);
17753 -- Create explicit stored discrims for untagged types when necessary
17755 if not Has_Unknown_Discriminants (Derived_Base)
17756 and then Has_Discriminants (Parent_Base)
17757 and then not Is_Tagged
17760 or else First_Discriminant (Parent_Base) /=
17761 First_Stored_Discriminant (Parent_Base))
17763 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17764 while Present (Stored_Discrim) loop
17765 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17766 Next_Stored_Discriminant (Stored_Discrim);
17770 -- See if we can apply the second transformation for derived types, as
17771 -- explained in point 6. in the comments above Build_Derived_Record_Type
17772 -- This is achieved by appending Derived_Base discriminants into Discs,
17773 -- which has the side effect of returning a non empty Discs list to the
17774 -- caller of Inherit_Components, which is what we want. This must be
17775 -- done for private derived types if there are explicit stored
17776 -- discriminants, to ensure that we can retrieve the values of the
17777 -- constraints provided in the ancestors.
17780 and then Is_Empty_Elmt_List (Discs)
17781 and then Present (First_Discriminant (Derived_Base))
17783 (not Is_Private_Type (Derived_Base)
17784 or else Is_Completely_Hidden
17785 (First_Stored_Discriminant (Derived_Base))
17786 or else Is_Generic_Type (Derived_Base))
17788 D := First_Discriminant (Derived_Base);
17789 while Present (D) loop
17790 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17791 Next_Discriminant (D);
17795 -- Finally, inherit non-discriminant components unless they are not
17796 -- visible because defined or inherited from the full view of the
17797 -- parent. Don't inherit the _parent field of the parent type.
17799 Component := First_Entity (Parent_Base);
17800 while Present (Component) loop
17802 -- Ada 2005 (AI-251): Do not inherit components associated with
17803 -- secondary tags of the parent.
17805 if Ekind (Component) = E_Component
17806 and then Present (Related_Type (Component))
17810 elsif Ekind (Component) /= E_Component
17811 or else Chars (Component) = Name_uParent
17815 -- If the derived type is within the parent type's declarative
17816 -- region, then the components can still be inherited even though
17817 -- they aren't visible at this point. This can occur for cases
17818 -- such as within public child units where the components must
17819 -- become visible upon entering the child unit's private part.
17821 elsif not Is_Visible_Component (Component)
17822 and then not In_Open_Scopes (Scope (Parent_Base))
17826 elsif Ekind_In (Derived_Base, E_Private_Type,
17827 E_Limited_Private_Type)
17832 Inherit_Component (Component);
17835 Next_Entity (Component);
17838 -- For tagged derived types, inherited discriminants cannot be used in
17839 -- component declarations of the record extension part. To achieve this
17840 -- we mark the inherited discriminants as not visible.
17842 if Is_Tagged and then Inherit_Discr then
17843 D := First_Discriminant (Derived_Base);
17844 while Present (D) loop
17845 Set_Is_Immediately_Visible (D, False);
17846 Next_Discriminant (D);
17851 end Inherit_Components;
17853 -----------------------------
17854 -- Inherit_Predicate_Flags --
17855 -----------------------------
17857 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17859 Set_Has_Predicates (Subt, Has_Predicates (Par));
17860 Set_Has_Static_Predicate_Aspect
17861 (Subt, Has_Static_Predicate_Aspect (Par));
17862 Set_Has_Dynamic_Predicate_Aspect
17863 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17864 end Inherit_Predicate_Flags;
17866 ----------------------
17867 -- Is_EVF_Procedure --
17868 ----------------------
17870 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17871 Formal : Entity_Id;
17874 -- Examine the formals of an Extensions_Visible False procedure looking
17875 -- for a controlling OUT parameter.
17877 if Ekind (Subp) = E_Procedure
17878 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17880 Formal := First_Formal (Subp);
17881 while Present (Formal) loop
17882 if Ekind (Formal) = E_Out_Parameter
17883 and then Is_Controlling_Formal (Formal)
17888 Next_Formal (Formal);
17893 end Is_EVF_Procedure;
17895 -----------------------
17896 -- Is_Null_Extension --
17897 -----------------------
17899 function Is_Null_Extension (T : Entity_Id) return Boolean is
17900 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17901 Comp_List : Node_Id;
17905 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17906 or else not Is_Tagged_Type (T)
17907 or else Nkind (Type_Definition (Type_Decl)) /=
17908 N_Derived_Type_Definition
17909 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17915 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17917 if Present (Discriminant_Specifications (Type_Decl)) then
17920 elsif Present (Comp_List)
17921 and then Is_Non_Empty_List (Component_Items (Comp_List))
17923 Comp := First (Component_Items (Comp_List));
17925 -- Only user-defined components are relevant. The component list
17926 -- may also contain a parent component and internal components
17927 -- corresponding to secondary tags, but these do not determine
17928 -- whether this is a null extension.
17930 while Present (Comp) loop
17931 if Comes_From_Source (Comp) then
17943 end Is_Null_Extension;
17945 ------------------------------
17946 -- Is_Valid_Constraint_Kind --
17947 ------------------------------
17949 function Is_Valid_Constraint_Kind
17950 (T_Kind : Type_Kind;
17951 Constraint_Kind : Node_Kind) return Boolean
17955 when Enumeration_Kind |
17957 return Constraint_Kind = N_Range_Constraint;
17959 when Decimal_Fixed_Point_Kind =>
17960 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17961 N_Range_Constraint);
17963 when Ordinary_Fixed_Point_Kind =>
17964 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17965 N_Range_Constraint);
17968 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17969 N_Range_Constraint);
17976 E_Incomplete_Type |
17979 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17982 return True; -- Error will be detected later
17984 end Is_Valid_Constraint_Kind;
17986 --------------------------
17987 -- Is_Visible_Component --
17988 --------------------------
17990 function Is_Visible_Component
17992 N : Node_Id := Empty) return Boolean
17994 Original_Comp : Entity_Id := Empty;
17995 Original_Type : Entity_Id;
17996 Type_Scope : Entity_Id;
17998 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17999 -- Check whether parent type of inherited component is declared locally,
18000 -- possibly within a nested package or instance. The current scope is
18001 -- the derived record itself.
18003 -------------------
18004 -- Is_Local_Type --
18005 -------------------
18007 function Is_Local_Type (Typ : Entity_Id) return Boolean is
18011 Scop := Scope (Typ);
18012 while Present (Scop)
18013 and then Scop /= Standard_Standard
18015 if Scop = Scope (Current_Scope) then
18019 Scop := Scope (Scop);
18025 -- Start of processing for Is_Visible_Component
18028 if Ekind_In (C, E_Component, E_Discriminant) then
18029 Original_Comp := Original_Record_Component (C);
18032 if No (Original_Comp) then
18034 -- Premature usage, or previous error
18039 Original_Type := Scope (Original_Comp);
18040 Type_Scope := Scope (Base_Type (Scope (C)));
18043 -- This test only concerns tagged types
18045 if not Is_Tagged_Type (Original_Type) then
18048 -- If it is _Parent or _Tag, there is no visibility issue
18050 elsif not Comes_From_Source (Original_Comp) then
18053 -- Discriminants are visible unless the (private) type has unknown
18054 -- discriminants. If the discriminant reference is inserted for a
18055 -- discriminant check on a full view it is also visible.
18057 elsif Ekind (Original_Comp) = E_Discriminant
18059 (not Has_Unknown_Discriminants (Original_Type)
18060 or else (Present (N)
18061 and then Nkind (N) = N_Selected_Component
18062 and then Nkind (Prefix (N)) = N_Type_Conversion
18063 and then not Comes_From_Source (Prefix (N))))
18067 -- In the body of an instantiation, no need to check for the visibility
18070 elsif In_Instance_Body then
18073 -- If the component has been declared in an ancestor which is currently
18074 -- a private type, then it is not visible. The same applies if the
18075 -- component's containing type is not in an open scope and the original
18076 -- component's enclosing type is a visible full view of a private type
18077 -- (which can occur in cases where an attempt is being made to reference
18078 -- a component in a sibling package that is inherited from a visible
18079 -- component of a type in an ancestor package; the component in the
18080 -- sibling package should not be visible even though the component it
18081 -- inherited from is visible). This does not apply however in the case
18082 -- where the scope of the type is a private child unit, or when the
18083 -- parent comes from a local package in which the ancestor is currently
18084 -- visible. The latter suppression of visibility is needed for cases
18085 -- that are tested in B730006.
18087 elsif Is_Private_Type (Original_Type)
18089 (not Is_Private_Descendant (Type_Scope)
18090 and then not In_Open_Scopes (Type_Scope)
18091 and then Has_Private_Declaration (Original_Type))
18093 -- If the type derives from an entity in a formal package, there
18094 -- are no additional visible components.
18096 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
18097 N_Formal_Package_Declaration
18101 -- if we are not in the private part of the current package, there
18102 -- are no additional visible components.
18104 elsif Ekind (Scope (Current_Scope)) = E_Package
18105 and then not In_Private_Part (Scope (Current_Scope))
18110 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
18111 and then In_Open_Scopes (Scope (Original_Type))
18112 and then Is_Local_Type (Type_Scope);
18115 -- There is another weird way in which a component may be invisible when
18116 -- the private and the full view are not derived from the same ancestor.
18117 -- Here is an example :
18119 -- type A1 is tagged record F1 : integer; end record;
18120 -- type A2 is new A1 with record F2 : integer; end record;
18121 -- type T is new A1 with private;
18123 -- type T is new A2 with null record;
18125 -- In this case, the full view of T inherits F1 and F2 but the private
18126 -- view inherits only F1
18130 Ancestor : Entity_Id := Scope (C);
18134 if Ancestor = Original_Type then
18137 -- The ancestor may have a partial view of the original type,
18138 -- but if the full view is in scope, as in a child body, the
18139 -- component is visible.
18141 elsif In_Private_Part (Scope (Original_Type))
18142 and then Full_View (Ancestor) = Original_Type
18146 elsif Ancestor = Etype (Ancestor) then
18148 -- No further ancestors to examine
18153 Ancestor := Etype (Ancestor);
18157 end Is_Visible_Component;
18159 --------------------------
18160 -- Make_Class_Wide_Type --
18161 --------------------------
18163 procedure Make_Class_Wide_Type (T : Entity_Id) is
18164 CW_Type : Entity_Id;
18166 Next_E : Entity_Id;
18169 if Present (Class_Wide_Type (T)) then
18171 -- The class-wide type is a partially decorated entity created for a
18172 -- unanalyzed tagged type referenced through a limited with clause.
18173 -- When the tagged type is analyzed, its class-wide type needs to be
18174 -- redecorated. Note that we reuse the entity created by Decorate_
18175 -- Tagged_Type in order to preserve all links.
18177 if Materialize_Entity (Class_Wide_Type (T)) then
18178 CW_Type := Class_Wide_Type (T);
18179 Set_Materialize_Entity (CW_Type, False);
18181 -- The class wide type can have been defined by the partial view, in
18182 -- which case everything is already done.
18188 -- Default case, we need to create a new class-wide type
18192 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18195 -- Inherit root type characteristics
18197 CW_Name := Chars (CW_Type);
18198 Next_E := Next_Entity (CW_Type);
18199 Copy_Node (T, CW_Type);
18200 Set_Comes_From_Source (CW_Type, False);
18201 Set_Chars (CW_Type, CW_Name);
18202 Set_Parent (CW_Type, Parent (T));
18203 Set_Next_Entity (CW_Type, Next_E);
18205 -- Ensure we have a new freeze node for the class-wide type. The partial
18206 -- view may have freeze action of its own, requiring a proper freeze
18207 -- node, and the same freeze node cannot be shared between the two
18210 Set_Has_Delayed_Freeze (CW_Type);
18211 Set_Freeze_Node (CW_Type, Empty);
18213 -- Customize the class-wide type: It has no prim. op., it cannot be
18214 -- abstract and its Etype points back to the specific root type.
18216 Set_Ekind (CW_Type, E_Class_Wide_Type);
18217 Set_Is_Tagged_Type (CW_Type, True);
18218 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18219 Set_Is_Abstract_Type (CW_Type, False);
18220 Set_Is_Constrained (CW_Type, False);
18221 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18222 Set_Default_SSO (CW_Type);
18224 if Ekind (T) = E_Class_Wide_Subtype then
18225 Set_Etype (CW_Type, Etype (Base_Type (T)));
18227 Set_Etype (CW_Type, T);
18230 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18232 -- If this is the class_wide type of a constrained subtype, it does
18233 -- not have discriminants.
18235 Set_Has_Discriminants (CW_Type,
18236 Has_Discriminants (T) and then not Is_Constrained (T));
18238 Set_Has_Unknown_Discriminants (CW_Type, True);
18239 Set_Class_Wide_Type (T, CW_Type);
18240 Set_Equivalent_Type (CW_Type, Empty);
18242 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18244 Set_Class_Wide_Type (CW_Type, CW_Type);
18246 -- Inherit the "ghostness" from the root tagged type
18248 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
18249 Set_Is_Ghost_Entity (CW_Type);
18251 end Make_Class_Wide_Type;
18257 procedure Make_Index
18259 Related_Nod : Node_Id;
18260 Related_Id : Entity_Id := Empty;
18261 Suffix_Index : Nat := 1;
18262 In_Iter_Schm : Boolean := False)
18266 Def_Id : Entity_Id := Empty;
18267 Found : Boolean := False;
18270 -- For a discrete range used in a constrained array definition and
18271 -- defined by a range, an implicit conversion to the predefined type
18272 -- INTEGER is assumed if each bound is either a numeric literal, a named
18273 -- number, or an attribute, and the type of both bounds (prior to the
18274 -- implicit conversion) is the type universal_integer. Otherwise, both
18275 -- bounds must be of the same discrete type, other than universal
18276 -- integer; this type must be determinable independently of the
18277 -- context, but using the fact that the type must be discrete and that
18278 -- both bounds must have the same type.
18280 -- Character literals also have a universal type in the absence of
18281 -- of additional context, and are resolved to Standard_Character.
18283 if Nkind (N) = N_Range then
18285 -- The index is given by a range constraint. The bounds are known
18286 -- to be of a consistent type.
18288 if not Is_Overloaded (N) then
18291 -- For universal bounds, choose the specific predefined type
18293 if T = Universal_Integer then
18294 T := Standard_Integer;
18296 elsif T = Any_Character then
18297 Ambiguous_Character (Low_Bound (N));
18299 T := Standard_Character;
18302 -- The node may be overloaded because some user-defined operators
18303 -- are available, but if a universal interpretation exists it is
18304 -- also the selected one.
18306 elsif Universal_Interpretation (N) = Universal_Integer then
18307 T := Standard_Integer;
18313 Ind : Interp_Index;
18317 Get_First_Interp (N, Ind, It);
18318 while Present (It.Typ) loop
18319 if Is_Discrete_Type (It.Typ) then
18322 and then not Covers (It.Typ, T)
18323 and then not Covers (T, It.Typ)
18325 Error_Msg_N ("ambiguous bounds in discrete range", N);
18333 Get_Next_Interp (Ind, It);
18336 if T = Any_Type then
18337 Error_Msg_N ("discrete type required for range", N);
18338 Set_Etype (N, Any_Type);
18341 elsif T = Universal_Integer then
18342 T := Standard_Integer;
18347 if not Is_Discrete_Type (T) then
18348 Error_Msg_N ("discrete type required for range", N);
18349 Set_Etype (N, Any_Type);
18353 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18354 and then Attribute_Name (Low_Bound (N)) = Name_First
18355 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18356 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18357 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18359 -- The type of the index will be the type of the prefix, as long
18360 -- as the upper bound is 'Last of the same type.
18362 Def_Id := Entity (Prefix (Low_Bound (N)));
18364 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18365 or else Attribute_Name (High_Bound (N)) /= Name_Last
18366 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18367 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18374 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18376 elsif Nkind (N) = N_Subtype_Indication then
18378 -- The index is given by a subtype with a range constraint
18380 T := Base_Type (Entity (Subtype_Mark (N)));
18382 if not Is_Discrete_Type (T) then
18383 Error_Msg_N ("discrete type required for range", N);
18384 Set_Etype (N, Any_Type);
18388 R := Range_Expression (Constraint (N));
18391 Process_Range_Expr_In_Decl
18392 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18394 elsif Nkind (N) = N_Attribute_Reference then
18396 -- Catch beginner's error (use of attribute other than 'Range)
18398 if Attribute_Name (N) /= Name_Range then
18399 Error_Msg_N ("expect attribute ''Range", N);
18400 Set_Etype (N, Any_Type);
18404 -- If the node denotes the range of a type mark, that is also the
18405 -- resulting type, and we do not need to create an Itype for it.
18407 if Is_Entity_Name (Prefix (N))
18408 and then Comes_From_Source (N)
18409 and then Is_Type (Entity (Prefix (N)))
18410 and then Is_Discrete_Type (Entity (Prefix (N)))
18412 Def_Id := Entity (Prefix (N));
18415 Analyze_And_Resolve (N);
18419 -- If none of the above, must be a subtype. We convert this to a
18420 -- range attribute reference because in the case of declared first
18421 -- named subtypes, the types in the range reference can be different
18422 -- from the type of the entity. A range attribute normalizes the
18423 -- reference and obtains the correct types for the bounds.
18425 -- This transformation is in the nature of an expansion, is only
18426 -- done if expansion is active. In particular, it is not done on
18427 -- formal generic types, because we need to retain the name of the
18428 -- original index for instantiation purposes.
18431 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18432 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18433 Set_Etype (N, Any_Integer);
18437 -- The type mark may be that of an incomplete type. It is only
18438 -- now that we can get the full view, previous analysis does
18439 -- not look specifically for a type mark.
18441 Set_Entity (N, Get_Full_View (Entity (N)));
18442 Set_Etype (N, Entity (N));
18443 Def_Id := Entity (N);
18445 if not Is_Discrete_Type (Def_Id) then
18446 Error_Msg_N ("discrete type required for index", N);
18447 Set_Etype (N, Any_Type);
18452 if Expander_Active then
18454 Make_Attribute_Reference (Sloc (N),
18455 Attribute_Name => Name_Range,
18456 Prefix => Relocate_Node (N)));
18458 -- The original was a subtype mark that does not freeze. This
18459 -- means that the rewritten version must not freeze either.
18461 Set_Must_Not_Freeze (N);
18462 Set_Must_Not_Freeze (Prefix (N));
18463 Analyze_And_Resolve (N);
18467 -- If expander is inactive, type is legal, nothing else to construct
18474 if not Is_Discrete_Type (T) then
18475 Error_Msg_N ("discrete type required for range", N);
18476 Set_Etype (N, Any_Type);
18479 elsif T = Any_Type then
18480 Set_Etype (N, Any_Type);
18484 -- We will now create the appropriate Itype to describe the range, but
18485 -- first a check. If we originally had a subtype, then we just label
18486 -- the range with this subtype. Not only is there no need to construct
18487 -- a new subtype, but it is wrong to do so for two reasons:
18489 -- 1. A legality concern, if we have a subtype, it must not freeze,
18490 -- and the Itype would cause freezing incorrectly
18492 -- 2. An efficiency concern, if we created an Itype, it would not be
18493 -- recognized as the same type for the purposes of eliminating
18494 -- checks in some circumstances.
18496 -- We signal this case by setting the subtype entity in Def_Id
18498 if No (Def_Id) then
18500 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18501 Set_Etype (Def_Id, Base_Type (T));
18503 if Is_Signed_Integer_Type (T) then
18504 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18506 elsif Is_Modular_Integer_Type (T) then
18507 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18510 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18511 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18512 Set_First_Literal (Def_Id, First_Literal (T));
18515 Set_Size_Info (Def_Id, (T));
18516 Set_RM_Size (Def_Id, RM_Size (T));
18517 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18519 Set_Scalar_Range (Def_Id, R);
18520 Conditional_Delay (Def_Id, T);
18522 if Nkind (N) = N_Subtype_Indication then
18523 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18526 -- In the subtype indication case, if the immediate parent of the
18527 -- new subtype is non-static, then the subtype we create is non-
18528 -- static, even if its bounds are static.
18530 if Nkind (N) = N_Subtype_Indication
18531 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18533 Set_Is_Non_Static_Subtype (Def_Id);
18537 -- Final step is to label the index with this constructed type
18539 Set_Etype (N, Def_Id);
18542 ------------------------------
18543 -- Modular_Type_Declaration --
18544 ------------------------------
18546 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18547 Mod_Expr : constant Node_Id := Expression (Def);
18550 procedure Set_Modular_Size (Bits : Int);
18551 -- Sets RM_Size to Bits, and Esize to normal word size above this
18553 ----------------------
18554 -- Set_Modular_Size --
18555 ----------------------
18557 procedure Set_Modular_Size (Bits : Int) is
18559 Set_RM_Size (T, UI_From_Int (Bits));
18564 elsif Bits <= 16 then
18565 Init_Esize (T, 16);
18567 elsif Bits <= 32 then
18568 Init_Esize (T, 32);
18571 Init_Esize (T, System_Max_Binary_Modulus_Power);
18574 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18575 Set_Is_Known_Valid (T);
18577 end Set_Modular_Size;
18579 -- Start of processing for Modular_Type_Declaration
18582 -- If the mod expression is (exactly) 2 * literal, where literal is
18583 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18585 if Warn_On_Suspicious_Modulus_Value
18586 and then Nkind (Mod_Expr) = N_Op_Multiply
18587 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18588 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18589 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18590 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18593 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18596 -- Proceed with analysis of mod expression
18598 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18600 Set_Ekind (T, E_Modular_Integer_Type);
18601 Init_Alignment (T);
18602 Set_Is_Constrained (T);
18604 if not Is_OK_Static_Expression (Mod_Expr) then
18605 Flag_Non_Static_Expr
18606 ("non-static expression used for modular type bound!", Mod_Expr);
18607 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18609 M_Val := Expr_Value (Mod_Expr);
18613 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18614 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18617 if M_Val > 2 ** Standard_Long_Integer_Size then
18618 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18621 Set_Modulus (T, M_Val);
18623 -- Create bounds for the modular type based on the modulus given in
18624 -- the type declaration and then analyze and resolve those bounds.
18626 Set_Scalar_Range (T,
18627 Make_Range (Sloc (Mod_Expr),
18628 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18629 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18631 -- Properly analyze the literals for the range. We do this manually
18632 -- because we can't go calling Resolve, since we are resolving these
18633 -- bounds with the type, and this type is certainly not complete yet.
18635 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18636 Set_Etype (High_Bound (Scalar_Range (T)), T);
18637 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18638 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18640 -- Loop through powers of two to find number of bits required
18642 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18646 if M_Val = 2 ** Bits then
18647 Set_Modular_Size (Bits);
18652 elsif M_Val < 2 ** Bits then
18653 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18654 Set_Non_Binary_Modulus (T);
18656 if Bits > System_Max_Nonbinary_Modulus_Power then
18657 Error_Msg_Uint_1 :=
18658 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18660 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18661 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18665 -- In the nonbinary case, set size as per RM 13.3(55)
18667 Set_Modular_Size (Bits);
18674 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18675 -- so we just signal an error and set the maximum size.
18677 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18678 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18680 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18681 Init_Alignment (T);
18683 end Modular_Type_Declaration;
18685 --------------------------
18686 -- New_Concatenation_Op --
18687 --------------------------
18689 procedure New_Concatenation_Op (Typ : Entity_Id) is
18690 Loc : constant Source_Ptr := Sloc (Typ);
18693 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18694 -- Create abbreviated declaration for the formal of a predefined
18695 -- Operator 'Op' of type 'Typ'
18697 --------------------
18698 -- Make_Op_Formal --
18699 --------------------
18701 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18702 Formal : Entity_Id;
18704 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18705 Set_Etype (Formal, Typ);
18706 Set_Mechanism (Formal, Default_Mechanism);
18708 end Make_Op_Formal;
18710 -- Start of processing for New_Concatenation_Op
18713 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18715 Set_Ekind (Op, E_Operator);
18716 Set_Scope (Op, Current_Scope);
18717 Set_Etype (Op, Typ);
18718 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18719 Set_Is_Immediately_Visible (Op);
18720 Set_Is_Intrinsic_Subprogram (Op);
18721 Set_Has_Completion (Op);
18722 Append_Entity (Op, Current_Scope);
18724 Set_Name_Entity_Id (Name_Op_Concat, Op);
18726 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18727 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18728 end New_Concatenation_Op;
18730 -------------------------
18731 -- OK_For_Limited_Init --
18732 -------------------------
18734 -- ???Check all calls of this, and compare the conditions under which it's
18737 function OK_For_Limited_Init
18739 Exp : Node_Id) return Boolean
18742 return Is_CPP_Constructor_Call (Exp)
18743 or else (Ada_Version >= Ada_2005
18744 and then not Debug_Flag_Dot_L
18745 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18746 end OK_For_Limited_Init;
18748 -------------------------------
18749 -- OK_For_Limited_Init_In_05 --
18750 -------------------------------
18752 function OK_For_Limited_Init_In_05
18754 Exp : Node_Id) return Boolean
18757 -- An object of a limited interface type can be initialized with any
18758 -- expression of a nonlimited descendant type. However this does not
18759 -- apply if this is a view conversion of some other expression. This
18760 -- is checked below.
18762 if Is_Class_Wide_Type (Typ)
18763 and then Is_Limited_Interface (Typ)
18764 and then not Is_Limited_Type (Etype (Exp))
18765 and then Nkind (Exp) /= N_Type_Conversion
18770 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18771 -- case of limited aggregates (including extension aggregates), and
18772 -- function calls. The function call may have been given in prefixed
18773 -- notation, in which case the original node is an indexed component.
18774 -- If the function is parameterless, the original node was an explicit
18775 -- dereference. The function may also be parameterless, in which case
18776 -- the source node is just an identifier.
18778 -- A branch of a conditional expression may have been removed if the
18779 -- condition is statically known. This happens during expansion, and
18780 -- thus will not happen if previous errors were encountered. The check
18781 -- will have been performed on the chosen branch, which replaces the
18782 -- original conditional expression.
18788 case Nkind (Original_Node (Exp)) is
18789 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18792 when N_Identifier =>
18793 return Present (Entity (Original_Node (Exp)))
18794 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18796 when N_Qualified_Expression =>
18798 OK_For_Limited_Init_In_05
18799 (Typ, Expression (Original_Node (Exp)));
18801 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18802 -- with a function call, the expander has rewritten the call into an
18803 -- N_Type_Conversion node to force displacement of the pointer to
18804 -- reference the component containing the secondary dispatch table.
18805 -- Otherwise a type conversion is not a legal context.
18806 -- A return statement for a build-in-place function returning a
18807 -- synchronized type also introduces an unchecked conversion.
18809 when N_Type_Conversion |
18810 N_Unchecked_Type_Conversion =>
18811 return not Comes_From_Source (Exp)
18813 OK_For_Limited_Init_In_05
18814 (Typ, Expression (Original_Node (Exp)));
18816 when N_Indexed_Component |
18817 N_Selected_Component |
18818 N_Explicit_Dereference =>
18819 return Nkind (Exp) = N_Function_Call;
18821 -- A use of 'Input is a function call, hence allowed. Normally the
18822 -- attribute will be changed to a call, but the attribute by itself
18823 -- can occur with -gnatc.
18825 when N_Attribute_Reference =>
18826 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18828 -- For a case expression, all dependent expressions must be legal
18830 when N_Case_Expression =>
18835 Alt := First (Alternatives (Original_Node (Exp)));
18836 while Present (Alt) loop
18837 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18847 -- For an if expression, all dependent expressions must be legal
18849 when N_If_Expression =>
18851 Then_Expr : constant Node_Id :=
18852 Next (First (Expressions (Original_Node (Exp))));
18853 Else_Expr : constant Node_Id := Next (Then_Expr);
18855 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18857 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18863 end OK_For_Limited_Init_In_05;
18865 -------------------------------------------
18866 -- Ordinary_Fixed_Point_Type_Declaration --
18867 -------------------------------------------
18869 procedure Ordinary_Fixed_Point_Type_Declaration
18873 Loc : constant Source_Ptr := Sloc (Def);
18874 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18875 RRS : constant Node_Id := Real_Range_Specification (Def);
18876 Implicit_Base : Entity_Id;
18883 Check_Restriction (No_Fixed_Point, Def);
18885 -- Create implicit base type
18888 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18889 Set_Etype (Implicit_Base, Implicit_Base);
18891 -- Analyze and process delta expression
18893 Analyze_And_Resolve (Delta_Expr, Any_Real);
18895 Check_Delta_Expression (Delta_Expr);
18896 Delta_Val := Expr_Value_R (Delta_Expr);
18898 Set_Delta_Value (Implicit_Base, Delta_Val);
18900 -- Compute default small from given delta, which is the largest power
18901 -- of two that does not exceed the given delta value.
18911 if Delta_Val < Ureal_1 then
18912 while Delta_Val < Tmp loop
18913 Tmp := Tmp / Ureal_2;
18914 Scale := Scale + 1;
18919 Tmp := Tmp * Ureal_2;
18920 exit when Tmp > Delta_Val;
18921 Scale := Scale - 1;
18925 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18928 Set_Small_Value (Implicit_Base, Small_Val);
18930 -- If no range was given, set a dummy range
18932 if RRS <= Empty_Or_Error then
18933 Low_Val := -Small_Val;
18934 High_Val := Small_Val;
18936 -- Otherwise analyze and process given range
18940 Low : constant Node_Id := Low_Bound (RRS);
18941 High : constant Node_Id := High_Bound (RRS);
18944 Analyze_And_Resolve (Low, Any_Real);
18945 Analyze_And_Resolve (High, Any_Real);
18946 Check_Real_Bound (Low);
18947 Check_Real_Bound (High);
18949 -- Obtain and set the range
18951 Low_Val := Expr_Value_R (Low);
18952 High_Val := Expr_Value_R (High);
18954 if Low_Val > High_Val then
18955 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18960 -- The range for both the implicit base and the declared first subtype
18961 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18962 -- set a temporary range in place. Note that the bounds of the base
18963 -- type will be widened to be symmetrical and to fill the available
18964 -- bits when the type is frozen.
18966 -- We could do this with all discrete types, and probably should, but
18967 -- we absolutely have to do it for fixed-point, since the end-points
18968 -- of the range and the size are determined by the small value, which
18969 -- could be reset before the freeze point.
18971 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18972 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18974 -- Complete definition of first subtype. The inheritance of the rep item
18975 -- chain ensures that SPARK-related pragmas are not clobbered when the
18976 -- ordinary fixed point type acts as a full view of a private type.
18978 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18979 Set_Etype (T, Implicit_Base);
18980 Init_Size_Align (T);
18981 Inherit_Rep_Item_Chain (T, Implicit_Base);
18982 Set_Small_Value (T, Small_Val);
18983 Set_Delta_Value (T, Delta_Val);
18984 Set_Is_Constrained (T);
18985 end Ordinary_Fixed_Point_Type_Declaration;
18987 ----------------------------------
18988 -- Preanalyze_Assert_Expression --
18989 ----------------------------------
18991 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18993 In_Assertion_Expr := In_Assertion_Expr + 1;
18994 Preanalyze_Spec_Expression (N, T);
18995 In_Assertion_Expr := In_Assertion_Expr - 1;
18996 end Preanalyze_Assert_Expression;
18998 -----------------------------------
18999 -- Preanalyze_Default_Expression --
19000 -----------------------------------
19002 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
19003 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
19005 In_Default_Expr := True;
19006 Preanalyze_Spec_Expression (N, T);
19007 In_Default_Expr := Save_In_Default_Expr;
19008 end Preanalyze_Default_Expression;
19010 --------------------------------
19011 -- Preanalyze_Spec_Expression --
19012 --------------------------------
19014 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19015 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19017 In_Spec_Expression := True;
19018 Preanalyze_And_Resolve (N, T);
19019 In_Spec_Expression := Save_In_Spec_Expression;
19020 end Preanalyze_Spec_Expression;
19022 ----------------------------------------
19023 -- Prepare_Private_Subtype_Completion --
19024 ----------------------------------------
19026 procedure Prepare_Private_Subtype_Completion
19028 Related_Nod : Node_Id)
19030 Id_B : constant Entity_Id := Base_Type (Id);
19031 Full_B : Entity_Id := Full_View (Id_B);
19035 if Present (Full_B) then
19037 -- Get to the underlying full view if necessary
19039 if Is_Private_Type (Full_B)
19040 and then Present (Underlying_Full_View (Full_B))
19042 Full_B := Underlying_Full_View (Full_B);
19045 -- The Base_Type is already completed, we can complete the subtype
19046 -- now. We have to create a new entity with the same name, Thus we
19047 -- can't use Create_Itype.
19049 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
19050 Set_Is_Itype (Full);
19051 Set_Associated_Node_For_Itype (Full, Related_Nod);
19052 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
19055 -- The parent subtype may be private, but the base might not, in some
19056 -- nested instances. In that case, the subtype does not need to be
19057 -- exchanged. It would still be nice to make private subtypes and their
19058 -- bases consistent at all times ???
19060 if Is_Private_Type (Id_B) then
19061 Append_Elmt (Id, Private_Dependents (Id_B));
19063 end Prepare_Private_Subtype_Completion;
19065 ---------------------------
19066 -- Process_Discriminants --
19067 ---------------------------
19069 procedure Process_Discriminants
19071 Prev : Entity_Id := Empty)
19073 Elist : constant Elist_Id := New_Elmt_List;
19076 Discr_Number : Uint;
19077 Discr_Type : Entity_Id;
19078 Default_Present : Boolean := False;
19079 Default_Not_Present : Boolean := False;
19082 -- A composite type other than an array type can have discriminants.
19083 -- On entry, the current scope is the composite type.
19085 -- The discriminants are initially entered into the scope of the type
19086 -- via Enter_Name with the default Ekind of E_Void to prevent premature
19087 -- use, as explained at the end of this procedure.
19089 Discr := First (Discriminant_Specifications (N));
19090 while Present (Discr) loop
19091 Enter_Name (Defining_Identifier (Discr));
19093 -- For navigation purposes we add a reference to the discriminant
19094 -- in the entity for the type. If the current declaration is a
19095 -- completion, place references on the partial view. Otherwise the
19096 -- type is the current scope.
19098 if Present (Prev) then
19100 -- The references go on the partial view, if present. If the
19101 -- partial view has discriminants, the references have been
19102 -- generated already.
19104 if not Has_Discriminants (Prev) then
19105 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
19109 (Current_Scope, Defining_Identifier (Discr), 'd');
19112 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
19113 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
19115 -- Ada 2005 (AI-254)
19117 if Present (Access_To_Subprogram_Definition
19118 (Discriminant_Type (Discr)))
19119 and then Protected_Present (Access_To_Subprogram_Definition
19120 (Discriminant_Type (Discr)))
19123 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
19127 Find_Type (Discriminant_Type (Discr));
19128 Discr_Type := Etype (Discriminant_Type (Discr));
19130 if Error_Posted (Discriminant_Type (Discr)) then
19131 Discr_Type := Any_Type;
19135 -- Handling of discriminants that are access types
19137 if Is_Access_Type (Discr_Type) then
19139 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19140 -- limited record types
19142 if Ada_Version < Ada_2005 then
19143 Check_Access_Discriminant_Requires_Limited
19144 (Discr, Discriminant_Type (Discr));
19147 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19149 ("(Ada 83) access discriminant not allowed", Discr);
19152 -- If not access type, must be a discrete type
19154 elsif not Is_Discrete_Type (Discr_Type) then
19156 ("discriminants must have a discrete or access type",
19157 Discriminant_Type (Discr));
19160 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19162 -- If a discriminant specification includes the assignment compound
19163 -- delimiter followed by an expression, the expression is the default
19164 -- expression of the discriminant; the default expression must be of
19165 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19166 -- a default expression, we do the special preanalysis, since this
19167 -- expression does not freeze (see section "Handling of Default and
19168 -- Per-Object Expressions" in spec of package Sem).
19170 if Present (Expression (Discr)) then
19171 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19175 if Nkind (N) = N_Formal_Type_Declaration then
19177 ("discriminant defaults not allowed for formal type",
19178 Expression (Discr));
19180 -- Flag an error for a tagged type with defaulted discriminants,
19181 -- excluding limited tagged types when compiling for Ada 2012
19182 -- (see AI05-0214).
19184 elsif Is_Tagged_Type (Current_Scope)
19185 and then (not Is_Limited_Type (Current_Scope)
19186 or else Ada_Version < Ada_2012)
19187 and then Comes_From_Source (N)
19189 -- Note: see similar test in Check_Or_Process_Discriminants, to
19190 -- handle the (illegal) case of the completion of an untagged
19191 -- view with discriminants with defaults by a tagged full view.
19192 -- We skip the check if Discr does not come from source, to
19193 -- account for the case of an untagged derived type providing
19194 -- defaults for a renamed discriminant from a private untagged
19195 -- ancestor with a tagged full view (ACATS B460006).
19197 if Ada_Version >= Ada_2012 then
19199 ("discriminants of nonlimited tagged type cannot have"
19201 Expression (Discr));
19204 ("discriminants of tagged type cannot have defaults",
19205 Expression (Discr));
19209 Default_Present := True;
19210 Append_Elmt (Expression (Discr), Elist);
19212 -- Tag the defining identifiers for the discriminants with
19213 -- their corresponding default expressions from the tree.
19215 Set_Discriminant_Default_Value
19216 (Defining_Identifier (Discr), Expression (Discr));
19219 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19220 -- gets set unless we can be sure that no range check is required.
19222 if (GNATprove_Mode or not Expander_Active)
19225 (Expression (Discr), Discr_Type, Assume_Valid => True)
19227 Set_Do_Range_Check (Expression (Discr));
19230 -- No default discriminant value given
19233 Default_Not_Present := True;
19236 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19237 -- Discr_Type but with the null-exclusion attribute
19239 if Ada_Version >= Ada_2005 then
19241 -- Ada 2005 (AI-231): Static checks
19243 if Can_Never_Be_Null (Discr_Type) then
19244 Null_Exclusion_Static_Checks (Discr);
19246 elsif Is_Access_Type (Discr_Type)
19247 and then Null_Exclusion_Present (Discr)
19249 -- No need to check itypes because in their case this check
19250 -- was done at their point of creation
19252 and then not Is_Itype (Discr_Type)
19254 if Can_Never_Be_Null (Discr_Type) then
19256 ("`NOT NULL` not allowed (& already excludes null)",
19261 Set_Etype (Defining_Identifier (Discr),
19262 Create_Null_Excluding_Itype
19264 Related_Nod => Discr));
19266 -- Check for improper null exclusion if the type is otherwise
19267 -- legal for a discriminant.
19269 elsif Null_Exclusion_Present (Discr)
19270 and then Is_Discrete_Type (Discr_Type)
19273 ("null exclusion can only apply to an access type", Discr);
19276 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19277 -- can't have defaults. Synchronized types, or types that are
19278 -- explicitly limited are fine, but special tests apply to derived
19279 -- types in generics: in a generic body we have to assume the
19280 -- worst, and therefore defaults are not allowed if the parent is
19281 -- a generic formal private type (see ACATS B370001).
19283 if Is_Access_Type (Discr_Type) and then Default_Present then
19284 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19285 or else Is_Limited_Record (Current_Scope)
19286 or else Is_Concurrent_Type (Current_Scope)
19287 or else Is_Concurrent_Record_Type (Current_Scope)
19288 or else Ekind (Current_Scope) = E_Limited_Private_Type
19290 if not Is_Derived_Type (Current_Scope)
19291 or else not Is_Generic_Type (Etype (Current_Scope))
19292 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19293 or else Limited_Present
19294 (Type_Definition (Parent (Current_Scope)))
19300 ("access discriminants of nonlimited types cannot "
19301 & "have defaults", Expression (Discr));
19304 elsif Present (Expression (Discr)) then
19306 ("(Ada 2005) access discriminants of nonlimited types "
19307 & "cannot have defaults", Expression (Discr));
19312 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19313 -- This check is relevant only when SPARK_Mode is on as it is not a
19314 -- standard Ada legality rule.
19317 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19319 Error_Msg_N ("discriminant cannot be volatile", Discr);
19325 -- An element list consisting of the default expressions of the
19326 -- discriminants is constructed in the above loop and used to set
19327 -- the Discriminant_Constraint attribute for the type. If an object
19328 -- is declared of this (record or task) type without any explicit
19329 -- discriminant constraint given, this element list will form the
19330 -- actual parameters for the corresponding initialization procedure
19333 Set_Discriminant_Constraint (Current_Scope, Elist);
19334 Set_Stored_Constraint (Current_Scope, No_Elist);
19336 -- Default expressions must be provided either for all or for none
19337 -- of the discriminants of a discriminant part. (RM 3.7.1)
19339 if Default_Present and then Default_Not_Present then
19341 ("incomplete specification of defaults for discriminants", N);
19344 -- The use of the name of a discriminant is not allowed in default
19345 -- expressions of a discriminant part if the specification of the
19346 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19348 -- To detect this, the discriminant names are entered initially with an
19349 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19350 -- attempt to use a void entity (for example in an expression that is
19351 -- type-checked) produces the error message: premature usage. Now after
19352 -- completing the semantic analysis of the discriminant part, we can set
19353 -- the Ekind of all the discriminants appropriately.
19355 Discr := First (Discriminant_Specifications (N));
19356 Discr_Number := Uint_1;
19357 while Present (Discr) loop
19358 Id := Defining_Identifier (Discr);
19359 Set_Ekind (Id, E_Discriminant);
19360 Init_Component_Location (Id);
19362 Set_Discriminant_Number (Id, Discr_Number);
19364 -- Make sure this is always set, even in illegal programs
19366 Set_Corresponding_Discriminant (Id, Empty);
19368 -- Initialize the Original_Record_Component to the entity itself.
19369 -- Inherit_Components will propagate the right value to
19370 -- discriminants in derived record types.
19372 Set_Original_Record_Component (Id, Id);
19374 -- Create the discriminal for the discriminant
19376 Build_Discriminal (Id);
19379 Discr_Number := Discr_Number + 1;
19382 Set_Has_Discriminants (Current_Scope);
19383 end Process_Discriminants;
19385 -----------------------
19386 -- Process_Full_View --
19387 -----------------------
19389 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19390 procedure Collect_Implemented_Interfaces
19392 Ifaces : Elist_Id);
19393 -- Ada 2005: Gather all the interfaces that Typ directly or
19394 -- inherently implements. Duplicate entries are not added to
19395 -- the list Ifaces.
19397 ------------------------------------
19398 -- Collect_Implemented_Interfaces --
19399 ------------------------------------
19401 procedure Collect_Implemented_Interfaces
19406 Iface_Elmt : Elmt_Id;
19409 -- Abstract interfaces are only associated with tagged record types
19411 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19415 -- Recursively climb to the ancestors
19417 if Etype (Typ) /= Typ
19419 -- Protect the frontend against wrong cyclic declarations like:
19421 -- type B is new A with private;
19422 -- type C is new A with private;
19424 -- type B is new C with null record;
19425 -- type C is new B with null record;
19427 and then Etype (Typ) /= Priv_T
19428 and then Etype (Typ) /= Full_T
19430 -- Keep separate the management of private type declarations
19432 if Ekind (Typ) = E_Record_Type_With_Private then
19434 -- Handle the following illegal usage:
19435 -- type Private_Type is tagged private;
19437 -- type Private_Type is new Type_Implementing_Iface;
19439 if Present (Full_View (Typ))
19440 and then Etype (Typ) /= Full_View (Typ)
19442 if Is_Interface (Etype (Typ)) then
19443 Append_Unique_Elmt (Etype (Typ), Ifaces);
19446 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19449 -- Non-private types
19452 if Is_Interface (Etype (Typ)) then
19453 Append_Unique_Elmt (Etype (Typ), Ifaces);
19456 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19460 -- Handle entities in the list of abstract interfaces
19462 if Present (Interfaces (Typ)) then
19463 Iface_Elmt := First_Elmt (Interfaces (Typ));
19464 while Present (Iface_Elmt) loop
19465 Iface := Node (Iface_Elmt);
19467 pragma Assert (Is_Interface (Iface));
19469 if not Contain_Interface (Iface, Ifaces) then
19470 Append_Elmt (Iface, Ifaces);
19471 Collect_Implemented_Interfaces (Iface, Ifaces);
19474 Next_Elmt (Iface_Elmt);
19477 end Collect_Implemented_Interfaces;
19481 Full_Indic : Node_Id;
19482 Full_Parent : Entity_Id;
19483 Priv_Parent : Entity_Id;
19485 -- Start of processing for Process_Full_View
19488 -- First some sanity checks that must be done after semantic
19489 -- decoration of the full view and thus cannot be placed with other
19490 -- similar checks in Find_Type_Name
19492 if not Is_Limited_Type (Priv_T)
19493 and then (Is_Limited_Type (Full_T)
19494 or else Is_Limited_Composite (Full_T))
19496 if In_Instance then
19500 ("completion of nonlimited type cannot be limited", Full_T);
19501 Explain_Limited_Type (Full_T, Full_T);
19504 elsif Is_Abstract_Type (Full_T)
19505 and then not Is_Abstract_Type (Priv_T)
19508 ("completion of nonabstract type cannot be abstract", Full_T);
19510 elsif Is_Tagged_Type (Priv_T)
19511 and then Is_Limited_Type (Priv_T)
19512 and then not Is_Limited_Type (Full_T)
19514 -- If pragma CPP_Class was applied to the private declaration
19515 -- propagate the limitedness to the full-view
19517 if Is_CPP_Class (Priv_T) then
19518 Set_Is_Limited_Record (Full_T);
19520 -- GNAT allow its own definition of Limited_Controlled to disobey
19521 -- this rule in order in ease the implementation. This test is safe
19522 -- because Root_Controlled is defined in a child of System that
19523 -- normal programs are not supposed to use.
19525 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19526 Set_Is_Limited_Composite (Full_T);
19529 ("completion of limited tagged type must be limited", Full_T);
19532 elsif Is_Generic_Type (Priv_T) then
19533 Error_Msg_N ("generic type cannot have a completion", Full_T);
19536 -- Check that ancestor interfaces of private and full views are
19537 -- consistent. We omit this check for synchronized types because
19538 -- they are performed on the corresponding record type when frozen.
19540 if Ada_Version >= Ada_2005
19541 and then Is_Tagged_Type (Priv_T)
19542 and then Is_Tagged_Type (Full_T)
19543 and then not Is_Concurrent_Type (Full_T)
19547 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19548 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19551 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19552 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19554 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19555 -- an interface type if and only if the full type is descendant
19556 -- of the interface type (AARM 7.3 (7.3/2)).
19558 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19560 if Present (Iface) then
19562 ("interface in partial view& not implemented by full type "
19563 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19566 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19568 if Present (Iface) then
19570 ("interface & not implemented by partial view "
19571 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19576 if Is_Tagged_Type (Priv_T)
19577 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19578 and then Is_Derived_Type (Full_T)
19580 Priv_Parent := Etype (Priv_T);
19582 -- The full view of a private extension may have been transformed
19583 -- into an unconstrained derived type declaration and a subtype
19584 -- declaration (see build_derived_record_type for details).
19586 if Nkind (N) = N_Subtype_Declaration then
19587 Full_Indic := Subtype_Indication (N);
19588 Full_Parent := Etype (Base_Type (Full_T));
19590 Full_Indic := Subtype_Indication (Type_Definition (N));
19591 Full_Parent := Etype (Full_T);
19594 -- Check that the parent type of the full type is a descendant of
19595 -- the ancestor subtype given in the private extension. If either
19596 -- entity has an Etype equal to Any_Type then we had some previous
19597 -- error situation [7.3(8)].
19599 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19602 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19603 -- any order. Therefore we don't have to check that its parent must
19604 -- be a descendant of the parent of the private type declaration.
19606 elsif Is_Interface (Priv_Parent)
19607 and then Is_Interface (Full_Parent)
19611 -- Ada 2005 (AI-251): If the parent of the private type declaration
19612 -- is an interface there is no need to check that it is an ancestor
19613 -- of the associated full type declaration. The required tests for
19614 -- this case are performed by Build_Derived_Record_Type.
19616 elsif not Is_Interface (Base_Type (Priv_Parent))
19617 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19620 ("parent of full type must descend from parent of private "
19621 & "extension", Full_Indic);
19623 -- First check a formal restriction, and then proceed with checking
19624 -- Ada rules. Since the formal restriction is not a serious error, we
19625 -- don't prevent further error detection for this check, hence the
19629 -- In formal mode, when completing a private extension the type
19630 -- named in the private part must be exactly the same as that
19631 -- named in the visible part.
19633 if Priv_Parent /= Full_Parent then
19634 Error_Msg_Name_1 := Chars (Priv_Parent);
19635 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19638 -- Check the rules of 7.3(10): if the private extension inherits
19639 -- known discriminants, then the full type must also inherit those
19640 -- discriminants from the same (ancestor) type, and the parent
19641 -- subtype of the full type must be constrained if and only if
19642 -- the ancestor subtype of the private extension is constrained.
19644 if No (Discriminant_Specifications (Parent (Priv_T)))
19645 and then not Has_Unknown_Discriminants (Priv_T)
19646 and then Has_Discriminants (Base_Type (Priv_Parent))
19649 Priv_Indic : constant Node_Id :=
19650 Subtype_Indication (Parent (Priv_T));
19652 Priv_Constr : constant Boolean :=
19653 Is_Constrained (Priv_Parent)
19655 Nkind (Priv_Indic) = N_Subtype_Indication
19657 Is_Constrained (Entity (Priv_Indic));
19659 Full_Constr : constant Boolean :=
19660 Is_Constrained (Full_Parent)
19662 Nkind (Full_Indic) = N_Subtype_Indication
19664 Is_Constrained (Entity (Full_Indic));
19666 Priv_Discr : Entity_Id;
19667 Full_Discr : Entity_Id;
19670 Priv_Discr := First_Discriminant (Priv_Parent);
19671 Full_Discr := First_Discriminant (Full_Parent);
19672 while Present (Priv_Discr) and then Present (Full_Discr) loop
19673 if Original_Record_Component (Priv_Discr) =
19674 Original_Record_Component (Full_Discr)
19676 Corresponding_Discriminant (Priv_Discr) =
19677 Corresponding_Discriminant (Full_Discr)
19684 Next_Discriminant (Priv_Discr);
19685 Next_Discriminant (Full_Discr);
19688 if Present (Priv_Discr) or else Present (Full_Discr) then
19690 ("full view must inherit discriminants of the parent "
19691 & "type used in the private extension", Full_Indic);
19693 elsif Priv_Constr and then not Full_Constr then
19695 ("parent subtype of full type must be constrained",
19698 elsif Full_Constr and then not Priv_Constr then
19700 ("parent subtype of full type must be unconstrained",
19705 -- Check the rules of 7.3(12): if a partial view has neither
19706 -- known or unknown discriminants, then the full type
19707 -- declaration shall define a definite subtype.
19709 elsif not Has_Unknown_Discriminants (Priv_T)
19710 and then not Has_Discriminants (Priv_T)
19711 and then not Is_Constrained (Full_T)
19714 ("full view must define a constrained type if partial view "
19715 & "has no discriminants", Full_T);
19718 -- ??????? Do we implement the following properly ?????
19719 -- If the ancestor subtype of a private extension has constrained
19720 -- discriminants, then the parent subtype of the full view shall
19721 -- impose a statically matching constraint on those discriminants
19726 -- For untagged types, verify that a type without discriminants is
19727 -- not completed with an unconstrained type. A separate error message
19728 -- is produced if the full type has defaulted discriminants.
19730 if Is_Definite_Subtype (Priv_T)
19731 and then not Is_Definite_Subtype (Full_T)
19733 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19735 ("full view of& not compatible with declaration#",
19738 if not Is_Tagged_Type (Full_T) then
19740 ("\one is constrained, the other unconstrained", Full_T);
19745 -- AI-419: verify that the use of "limited" is consistent
19748 Orig_Decl : constant Node_Id := Original_Node (N);
19751 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19752 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19754 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19756 if not Limited_Present (Parent (Priv_T))
19757 and then not Synchronized_Present (Parent (Priv_T))
19758 and then Limited_Present (Type_Definition (Orig_Decl))
19761 ("full view of non-limited extension cannot be limited", N);
19763 -- Conversely, if the partial view carries the limited keyword,
19764 -- the full view must as well, even if it may be redundant.
19766 elsif Limited_Present (Parent (Priv_T))
19767 and then not Limited_Present (Type_Definition (Orig_Decl))
19770 ("full view of limited extension must be explicitly limited",
19776 -- Ada 2005 (AI-443): A synchronized private extension must be
19777 -- completed by a task or protected type.
19779 if Ada_Version >= Ada_2005
19780 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19781 and then Synchronized_Present (Parent (Priv_T))
19782 and then not Is_Concurrent_Type (Full_T)
19784 Error_Msg_N ("full view of synchronized extension must " &
19785 "be synchronized type", N);
19788 -- Ada 2005 AI-363: if the full view has discriminants with
19789 -- defaults, it is illegal to declare constrained access subtypes
19790 -- whose designated type is the current type. This allows objects
19791 -- of the type that are declared in the heap to be unconstrained.
19793 if not Has_Unknown_Discriminants (Priv_T)
19794 and then not Has_Discriminants (Priv_T)
19795 and then Has_Discriminants (Full_T)
19797 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19799 Set_Has_Constrained_Partial_View (Full_T);
19800 Set_Has_Constrained_Partial_View (Priv_T);
19803 -- Create a full declaration for all its subtypes recorded in
19804 -- Private_Dependents and swap them similarly to the base type. These
19805 -- are subtypes that have been define before the full declaration of
19806 -- the private type. We also swap the entry in Private_Dependents list
19807 -- so we can properly restore the private view on exit from the scope.
19810 Priv_Elmt : Elmt_Id;
19811 Priv_Scop : Entity_Id;
19816 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19817 while Present (Priv_Elmt) loop
19818 Priv := Node (Priv_Elmt);
19819 Priv_Scop := Scope (Priv);
19821 if Ekind_In (Priv, E_Private_Subtype,
19822 E_Limited_Private_Subtype,
19823 E_Record_Subtype_With_Private)
19825 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19826 Set_Is_Itype (Full);
19827 Set_Parent (Full, Parent (Priv));
19828 Set_Associated_Node_For_Itype (Full, N);
19830 -- Now we need to complete the private subtype, but since the
19831 -- base type has already been swapped, we must also swap the
19832 -- subtypes (and thus, reverse the arguments in the call to
19833 -- Complete_Private_Subtype). Also note that we may need to
19834 -- re-establish the scope of the private subtype.
19836 Copy_And_Swap (Priv, Full);
19838 if not In_Open_Scopes (Priv_Scop) then
19839 Push_Scope (Priv_Scop);
19842 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19844 Priv_Scop := Empty;
19847 Complete_Private_Subtype (Full, Priv, Full_T, N);
19849 if Present (Priv_Scop) then
19853 Replace_Elmt (Priv_Elmt, Full);
19856 Next_Elmt (Priv_Elmt);
19860 -- If the private view was tagged, copy the new primitive operations
19861 -- from the private view to the full view.
19863 if Is_Tagged_Type (Full_T) then
19865 Disp_Typ : Entity_Id;
19866 Full_List : Elist_Id;
19868 Prim_Elmt : Elmt_Id;
19869 Priv_List : Elist_Id;
19873 L : Elist_Id) return Boolean;
19874 -- Determine whether list L contains element E
19882 L : Elist_Id) return Boolean
19884 List_Elmt : Elmt_Id;
19887 List_Elmt := First_Elmt (L);
19888 while Present (List_Elmt) loop
19889 if Node (List_Elmt) = E then
19893 Next_Elmt (List_Elmt);
19899 -- Start of processing
19902 if Is_Tagged_Type (Priv_T) then
19903 Priv_List := Primitive_Operations (Priv_T);
19904 Prim_Elmt := First_Elmt (Priv_List);
19906 -- In the case of a concurrent type completing a private tagged
19907 -- type, primitives may have been declared in between the two
19908 -- views. These subprograms need to be wrapped the same way
19909 -- entries and protected procedures are handled because they
19910 -- cannot be directly shared by the two views.
19912 if Is_Concurrent_Type (Full_T) then
19914 Conc_Typ : constant Entity_Id :=
19915 Corresponding_Record_Type (Full_T);
19916 Curr_Nod : Node_Id := Parent (Conc_Typ);
19917 Wrap_Spec : Node_Id;
19920 while Present (Prim_Elmt) loop
19921 Prim := Node (Prim_Elmt);
19923 if Comes_From_Source (Prim)
19924 and then not Is_Abstract_Subprogram (Prim)
19927 Make_Subprogram_Declaration (Sloc (Prim),
19931 Obj_Typ => Conc_Typ,
19933 Parameter_Specifications
19936 Insert_After (Curr_Nod, Wrap_Spec);
19937 Curr_Nod := Wrap_Spec;
19939 Analyze (Wrap_Spec);
19941 -- Remove the wrapper from visibility to avoid
19942 -- spurious conflict with the wrapped entity.
19944 Set_Is_Immediately_Visible
19945 (Defining_Entity (Specification (Wrap_Spec)),
19949 Next_Elmt (Prim_Elmt);
19955 -- For non-concurrent types, transfer explicit primitives, but
19956 -- omit those inherited from the parent of the private view
19957 -- since they will be re-inherited later on.
19960 Full_List := Primitive_Operations (Full_T);
19962 while Present (Prim_Elmt) loop
19963 Prim := Node (Prim_Elmt);
19965 if Comes_From_Source (Prim)
19966 and then not Contains (Prim, Full_List)
19968 Append_Elmt (Prim, Full_List);
19971 Next_Elmt (Prim_Elmt);
19975 -- Untagged private view
19978 Full_List := Primitive_Operations (Full_T);
19980 -- In this case the partial view is untagged, so here we locate
19981 -- all of the earlier primitives that need to be treated as
19982 -- dispatching (those that appear between the two views). Note
19983 -- that these additional operations must all be new operations
19984 -- (any earlier operations that override inherited operations
19985 -- of the full view will already have been inserted in the
19986 -- primitives list, marked by Check_Operation_From_Private_View
19987 -- as dispatching. Note that implicit "/=" operators are
19988 -- excluded from being added to the primitives list since they
19989 -- shouldn't be treated as dispatching (tagged "/=" is handled
19992 Prim := Next_Entity (Full_T);
19993 while Present (Prim) and then Prim /= Priv_T loop
19994 if Ekind_In (Prim, E_Procedure, E_Function) then
19995 Disp_Typ := Find_Dispatching_Type (Prim);
19997 if Disp_Typ = Full_T
19998 and then (Chars (Prim) /= Name_Op_Ne
19999 or else Comes_From_Source (Prim))
20001 Check_Controlling_Formals (Full_T, Prim);
20003 if not Is_Dispatching_Operation (Prim) then
20004 Append_Elmt (Prim, Full_List);
20005 Set_Is_Dispatching_Operation (Prim, True);
20006 Set_DT_Position_Value (Prim, No_Uint);
20009 elsif Is_Dispatching_Operation (Prim)
20010 and then Disp_Typ /= Full_T
20013 -- Verify that it is not otherwise controlled by a
20014 -- formal or a return value of type T.
20016 Check_Controlling_Formals (Disp_Typ, Prim);
20020 Next_Entity (Prim);
20024 -- For the tagged case, the two views can share the same primitive
20025 -- operations list and the same class-wide type. Update attributes
20026 -- of the class-wide type which depend on the full declaration.
20028 if Is_Tagged_Type (Priv_T) then
20029 Set_Direct_Primitive_Operations (Priv_T, Full_List);
20030 Set_Class_Wide_Type
20031 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
20033 Propagate_Concurrent_Flags (Class_Wide_Type (Priv_T), Full_T);
20038 -- Ada 2005 AI 161: Check preelaborable initialization consistency
20040 if Known_To_Have_Preelab_Init (Priv_T) then
20042 -- Case where there is a pragma Preelaborable_Initialization. We
20043 -- always allow this in predefined units, which is cheating a bit,
20044 -- but it means we don't have to struggle to meet the requirements in
20045 -- the RM for having Preelaborable Initialization. Otherwise we
20046 -- require that the type meets the RM rules. But we can't check that
20047 -- yet, because of the rule about overriding Initialize, so we simply
20048 -- set a flag that will be checked at freeze time.
20050 if not In_Predefined_Unit (Full_T) then
20051 Set_Must_Have_Preelab_Init (Full_T);
20055 -- If pragma CPP_Class was applied to the private type declaration,
20056 -- propagate it now to the full type declaration.
20058 if Is_CPP_Class (Priv_T) then
20059 Set_Is_CPP_Class (Full_T);
20060 Set_Convention (Full_T, Convention_CPP);
20062 -- Check that components of imported CPP types do not have default
20065 Check_CPP_Type_Has_No_Defaults (Full_T);
20068 -- If the private view has user specified stream attributes, then so has
20071 -- Why the test, how could these flags be already set in Full_T ???
20073 if Has_Specified_Stream_Read (Priv_T) then
20074 Set_Has_Specified_Stream_Read (Full_T);
20077 if Has_Specified_Stream_Write (Priv_T) then
20078 Set_Has_Specified_Stream_Write (Full_T);
20081 if Has_Specified_Stream_Input (Priv_T) then
20082 Set_Has_Specified_Stream_Input (Full_T);
20085 if Has_Specified_Stream_Output (Priv_T) then
20086 Set_Has_Specified_Stream_Output (Full_T);
20089 -- Propagate the attributes related to pragma Default_Initial_Condition
20090 -- from the private to the full view. Note that both flags are mutually
20093 if Has_Default_Init_Cond (Priv_T)
20094 or else Has_Inherited_Default_Init_Cond (Priv_T)
20096 Propagate_Default_Init_Cond_Attributes
20097 (From_Typ => Priv_T,
20099 Private_To_Full_View => True);
20101 -- In the case where the full view is derived from another private type,
20102 -- the attributes related to pragma Default_Initial_Condition must be
20103 -- propagated from the full to the private view to maintain consistency
20107 -- type Parent_Typ is private
20108 -- with Default_Initial_Condition ...;
20110 -- type Parent_Typ is ...;
20113 -- with Pack; use Pack;
20114 -- package Pack_2 is
20115 -- type Deriv_Typ is private; -- must inherit
20117 -- type Deriv_Typ is new Parent_Typ; -- must inherit
20120 elsif Has_Default_Init_Cond (Full_T)
20121 or else Has_Inherited_Default_Init_Cond (Full_T)
20123 Propagate_Default_Init_Cond_Attributes
20124 (From_Typ => Full_T,
20126 Private_To_Full_View => True);
20129 if Is_Ghost_Entity (Priv_T) then
20131 -- The Ghost policy in effect at the point of declaration and at the
20132 -- point of completion must match (SPARK RM 6.9(14)).
20134 Check_Ghost_Completion (Priv_T, Full_T);
20136 -- Propagate the attributes related to pragma Ghost from the private
20137 -- to the full view.
20139 Mark_Full_View_As_Ghost (Priv_T, Full_T);
20142 -- Propagate invariant-related attributes from the private view to the
20143 -- full view and its base type.
20145 Propagate_Invariant_Attributes (Full_T, From_Typ => Priv_T);
20146 Propagate_Invariant_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20148 -- AI12-0041: Detect an attempt to inherit a class-wide type invariant
20149 -- in the full view without advertising the inheritance in the partial
20150 -- view. This can only occur when the partial view has no parent type
20151 -- and the full view has an interface as a parent. Any other scenarios
20152 -- are illegal because implemented interfaces must match between the
20155 if Is_Tagged_Type (Priv_T) and then Is_Tagged_Type (Full_T) then
20157 Full_Par : constant Entity_Id := Etype (Full_T);
20158 Priv_Par : constant Entity_Id := Etype (Priv_T);
20161 if not Is_Interface (Priv_Par)
20162 and then Is_Interface (Full_Par)
20163 and then Has_Inheritable_Invariants (Full_Par)
20166 ("hidden inheritance of class-wide type invariants not "
20172 -- Propagate predicates to full type, and predicate function if already
20173 -- defined. It is not clear that this can actually happen? the partial
20174 -- view cannot be frozen yet, and the predicate function has not been
20175 -- built. Still it is a cheap check and seems safer to make it.
20177 if Has_Predicates (Priv_T) then
20178 Set_Has_Predicates (Full_T);
20180 if Present (Predicate_Function (Priv_T)) then
20181 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20184 end Process_Full_View;
20186 -----------------------------------
20187 -- Process_Incomplete_Dependents --
20188 -----------------------------------
20190 procedure Process_Incomplete_Dependents
20192 Full_T : Entity_Id;
20195 Inc_Elmt : Elmt_Id;
20196 Priv_Dep : Entity_Id;
20197 New_Subt : Entity_Id;
20199 Disc_Constraint : Elist_Id;
20202 if No (Private_Dependents (Inc_T)) then
20206 -- Itypes that may be generated by the completion of an incomplete
20207 -- subtype are not used by the back-end and not attached to the tree.
20208 -- They are created only for constraint-checking purposes.
20210 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20211 while Present (Inc_Elmt) loop
20212 Priv_Dep := Node (Inc_Elmt);
20214 if Ekind (Priv_Dep) = E_Subprogram_Type then
20216 -- An Access_To_Subprogram type may have a return type or a
20217 -- parameter type that is incomplete. Replace with the full view.
20219 if Etype (Priv_Dep) = Inc_T then
20220 Set_Etype (Priv_Dep, Full_T);
20224 Formal : Entity_Id;
20227 Formal := First_Formal (Priv_Dep);
20228 while Present (Formal) loop
20229 if Etype (Formal) = Inc_T then
20230 Set_Etype (Formal, Full_T);
20233 Next_Formal (Formal);
20237 elsif Is_Overloadable (Priv_Dep) then
20239 -- If a subprogram in the incomplete dependents list is primitive
20240 -- for a tagged full type then mark it as a dispatching operation,
20241 -- check whether it overrides an inherited subprogram, and check
20242 -- restrictions on its controlling formals. Note that a protected
20243 -- operation is never dispatching: only its wrapper operation
20244 -- (which has convention Ada) is.
20246 if Is_Tagged_Type (Full_T)
20247 and then Is_Primitive (Priv_Dep)
20248 and then Convention (Priv_Dep) /= Convention_Protected
20250 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20251 Set_Is_Dispatching_Operation (Priv_Dep);
20252 Check_Controlling_Formals (Full_T, Priv_Dep);
20255 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20257 -- Can happen during processing of a body before the completion
20258 -- of a TA type. Ignore, because spec is also on dependent list.
20262 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20263 -- corresponding subtype of the full view.
20265 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20266 Set_Subtype_Indication
20267 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20268 Set_Etype (Priv_Dep, Full_T);
20269 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20270 Set_Analyzed (Parent (Priv_Dep), False);
20272 -- Reanalyze the declaration, suppressing the call to
20273 -- Enter_Name to avoid duplicate names.
20275 Analyze_Subtype_Declaration
20276 (N => Parent (Priv_Dep),
20279 -- Dependent is a subtype
20282 -- We build a new subtype indication using the full view of the
20283 -- incomplete parent. The discriminant constraints have been
20284 -- elaborated already at the point of the subtype declaration.
20286 New_Subt := Create_Itype (E_Void, N);
20288 if Has_Discriminants (Full_T) then
20289 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20291 Disc_Constraint := No_Elist;
20294 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20295 Set_Full_View (Priv_Dep, New_Subt);
20298 Next_Elmt (Inc_Elmt);
20300 end Process_Incomplete_Dependents;
20302 --------------------------------
20303 -- Process_Range_Expr_In_Decl --
20304 --------------------------------
20306 procedure Process_Range_Expr_In_Decl
20309 Subtyp : Entity_Id := Empty;
20310 Check_List : List_Id := Empty_List;
20311 R_Check_Off : Boolean := False;
20312 In_Iter_Schm : Boolean := False)
20315 R_Checks : Check_Result;
20316 Insert_Node : Node_Id;
20317 Def_Id : Entity_Id;
20320 Analyze_And_Resolve (R, Base_Type (T));
20322 if Nkind (R) = N_Range then
20324 -- In SPARK, all ranges should be static, with the exception of the
20325 -- discrete type definition of a loop parameter specification.
20327 if not In_Iter_Schm
20328 and then not Is_OK_Static_Range (R)
20330 Check_SPARK_05_Restriction ("range should be static", R);
20333 Lo := Low_Bound (R);
20334 Hi := High_Bound (R);
20336 -- Validity checks on the range of a quantified expression are
20337 -- delayed until the construct is transformed into a loop.
20339 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20340 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20344 -- We need to ensure validity of the bounds here, because if we
20345 -- go ahead and do the expansion, then the expanded code will get
20346 -- analyzed with range checks suppressed and we miss the check.
20348 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20349 -- the temporaries generated by routine Remove_Side_Effects by means
20350 -- of validity checks must use the same names. When a range appears
20351 -- in the parent of a generic, the range is processed with checks
20352 -- disabled as part of the generic context and with checks enabled
20353 -- for code generation purposes. This leads to link issues as the
20354 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20355 -- template sees the temporaries generated by Remove_Side_Effects.
20358 Validity_Check_Range (R, Subtyp);
20361 -- If there were errors in the declaration, try and patch up some
20362 -- common mistakes in the bounds. The cases handled are literals
20363 -- which are Integer where the expected type is Real and vice versa.
20364 -- These corrections allow the compilation process to proceed further
20365 -- along since some basic assumptions of the format of the bounds
20368 if Etype (R) = Any_Type then
20369 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20371 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20373 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20375 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20377 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20379 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20381 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20383 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20390 -- If the bounds of the range have been mistakenly given as string
20391 -- literals (perhaps in place of character literals), then an error
20392 -- has already been reported, but we rewrite the string literal as a
20393 -- bound of the range's type to avoid blowups in later processing
20394 -- that looks at static values.
20396 if Nkind (Lo) = N_String_Literal then
20398 Make_Attribute_Reference (Sloc (Lo),
20399 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20400 Attribute_Name => Name_First));
20401 Analyze_And_Resolve (Lo);
20404 if Nkind (Hi) = N_String_Literal then
20406 Make_Attribute_Reference (Sloc (Hi),
20407 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20408 Attribute_Name => Name_First));
20409 Analyze_And_Resolve (Hi);
20412 -- If bounds aren't scalar at this point then exit, avoiding
20413 -- problems with further processing of the range in this procedure.
20415 if not Is_Scalar_Type (Etype (Lo)) then
20419 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20420 -- then range of the base type. Here we check whether the bounds
20421 -- are in the range of the subtype itself. Note that if the bounds
20422 -- represent the null range the Constraint_Error exception should
20425 -- ??? The following code should be cleaned up as follows
20427 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20428 -- is done in the call to Range_Check (R, T); below
20430 -- 2. The use of R_Check_Off should be investigated and possibly
20431 -- removed, this would clean up things a bit.
20433 if Is_Null_Range (Lo, Hi) then
20437 -- Capture values of bounds and generate temporaries for them
20438 -- if needed, before applying checks, since checks may cause
20439 -- duplication of the expression without forcing evaluation.
20441 -- The forced evaluation removes side effects from expressions,
20442 -- which should occur also in GNATprove mode. Otherwise, we end up
20443 -- with unexpected insertions of actions at places where this is
20444 -- not supposed to occur, e.g. on default parameters of a call.
20446 if Expander_Active or GNATprove_Mode then
20448 -- Call Force_Evaluation to create declarations as needed to
20449 -- deal with side effects, and also create typ_FIRST/LAST
20450 -- entities for bounds if we have a subtype name.
20452 -- Note: we do this transformation even if expansion is not
20453 -- active if we are in GNATprove_Mode since the transformation
20454 -- is in general required to ensure that the resulting tree has
20455 -- proper Ada semantics.
20458 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20460 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20463 -- We use a flag here instead of suppressing checks on the type
20464 -- because the type we check against isn't necessarily the place
20465 -- where we put the check.
20467 if not R_Check_Off then
20468 R_Checks := Get_Range_Checks (R, T);
20470 -- Look up tree to find an appropriate insertion point. We
20471 -- can't just use insert_actions because later processing
20472 -- depends on the insertion node. Prior to Ada 2012 the
20473 -- insertion point could only be a declaration or a loop, but
20474 -- quantified expressions can appear within any context in an
20475 -- expression, and the insertion point can be any statement,
20476 -- pragma, or declaration.
20478 Insert_Node := Parent (R);
20479 while Present (Insert_Node) loop
20481 Nkind (Insert_Node) in N_Declaration
20484 (Insert_Node, N_Component_Declaration,
20485 N_Loop_Parameter_Specification,
20486 N_Function_Specification,
20487 N_Procedure_Specification);
20489 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20490 or else Nkind (Insert_Node) in
20491 N_Statement_Other_Than_Procedure_Call
20492 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20495 Insert_Node := Parent (Insert_Node);
20498 -- Why would Type_Decl not be present??? Without this test,
20499 -- short regression tests fail.
20501 if Present (Insert_Node) then
20503 -- Case of loop statement. Verify that the range is part
20504 -- of the subtype indication of the iteration scheme.
20506 if Nkind (Insert_Node) = N_Loop_Statement then
20511 Indic := Parent (R);
20512 while Present (Indic)
20513 and then Nkind (Indic) /= N_Subtype_Indication
20515 Indic := Parent (Indic);
20518 if Present (Indic) then
20519 Def_Id := Etype (Subtype_Mark (Indic));
20521 Insert_Range_Checks
20525 Sloc (Insert_Node),
20527 Do_Before => True);
20531 -- Insertion before a declaration. If the declaration
20532 -- includes discriminants, the list of applicable checks
20533 -- is given by the caller.
20535 elsif Nkind (Insert_Node) in N_Declaration then
20536 Def_Id := Defining_Identifier (Insert_Node);
20538 if (Ekind (Def_Id) = E_Record_Type
20539 and then Depends_On_Discriminant (R))
20541 (Ekind (Def_Id) = E_Protected_Type
20542 and then Has_Discriminants (Def_Id))
20544 Append_Range_Checks
20546 Check_List, Def_Id, Sloc (Insert_Node), R);
20549 Insert_Range_Checks
20551 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20555 -- Insertion before a statement. Range appears in the
20556 -- context of a quantified expression. Insertion will
20557 -- take place when expression is expanded.
20566 -- Case of other than an explicit N_Range node
20568 -- The forced evaluation removes side effects from expressions, which
20569 -- should occur also in GNATprove mode. Otherwise, we end up with
20570 -- unexpected insertions of actions at places where this is not
20571 -- supposed to occur, e.g. on default parameters of a call.
20573 elsif Expander_Active or GNATprove_Mode then
20574 Get_Index_Bounds (R, Lo, Hi);
20575 Force_Evaluation (Lo);
20576 Force_Evaluation (Hi);
20578 end Process_Range_Expr_In_Decl;
20580 --------------------------------------
20581 -- Process_Real_Range_Specification --
20582 --------------------------------------
20584 procedure Process_Real_Range_Specification (Def : Node_Id) is
20585 Spec : constant Node_Id := Real_Range_Specification (Def);
20588 Err : Boolean := False;
20590 procedure Analyze_Bound (N : Node_Id);
20591 -- Analyze and check one bound
20593 -------------------
20594 -- Analyze_Bound --
20595 -------------------
20597 procedure Analyze_Bound (N : Node_Id) is
20599 Analyze_And_Resolve (N, Any_Real);
20601 if not Is_OK_Static_Expression (N) then
20602 Flag_Non_Static_Expr
20603 ("bound in real type definition is not static!", N);
20608 -- Start of processing for Process_Real_Range_Specification
20611 if Present (Spec) then
20612 Lo := Low_Bound (Spec);
20613 Hi := High_Bound (Spec);
20614 Analyze_Bound (Lo);
20615 Analyze_Bound (Hi);
20617 -- If error, clear away junk range specification
20620 Set_Real_Range_Specification (Def, Empty);
20623 end Process_Real_Range_Specification;
20625 ---------------------
20626 -- Process_Subtype --
20627 ---------------------
20629 function Process_Subtype
20631 Related_Nod : Node_Id;
20632 Related_Id : Entity_Id := Empty;
20633 Suffix : Character := ' ') return Entity_Id
20636 Def_Id : Entity_Id;
20637 Error_Node : Node_Id;
20638 Full_View_Id : Entity_Id;
20639 Subtype_Mark_Id : Entity_Id;
20641 May_Have_Null_Exclusion : Boolean;
20643 procedure Check_Incomplete (T : Node_Id);
20644 -- Called to verify that an incomplete type is not used prematurely
20646 ----------------------
20647 -- Check_Incomplete --
20648 ----------------------
20650 procedure Check_Incomplete (T : Node_Id) is
20652 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20654 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20656 not (Ada_Version >= Ada_2005
20658 (Nkind (Parent (T)) = N_Subtype_Declaration
20659 or else (Nkind (Parent (T)) = N_Subtype_Indication
20660 and then Nkind (Parent (Parent (T))) =
20661 N_Subtype_Declaration)))
20663 Error_Msg_N ("invalid use of type before its full declaration", T);
20665 end Check_Incomplete;
20667 -- Start of processing for Process_Subtype
20670 -- Case of no constraints present
20672 if Nkind (S) /= N_Subtype_Indication then
20674 Check_Incomplete (S);
20677 -- Ada 2005 (AI-231): Static check
20679 if Ada_Version >= Ada_2005
20680 and then Present (P)
20681 and then Null_Exclusion_Present (P)
20682 and then Nkind (P) /= N_Access_To_Object_Definition
20683 and then not Is_Access_Type (Entity (S))
20685 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20688 -- The following is ugly, can't we have a range or even a flag???
20690 May_Have_Null_Exclusion :=
20691 Nkind_In (P, N_Access_Definition,
20692 N_Access_Function_Definition,
20693 N_Access_Procedure_Definition,
20694 N_Access_To_Object_Definition,
20696 N_Component_Definition)
20698 Nkind_In (P, N_Derived_Type_Definition,
20699 N_Discriminant_Specification,
20700 N_Formal_Object_Declaration,
20701 N_Object_Declaration,
20702 N_Object_Renaming_Declaration,
20703 N_Parameter_Specification,
20704 N_Subtype_Declaration);
20706 -- Create an Itype that is a duplicate of Entity (S) but with the
20707 -- null-exclusion attribute.
20709 if May_Have_Null_Exclusion
20710 and then Is_Access_Type (Entity (S))
20711 and then Null_Exclusion_Present (P)
20713 -- No need to check the case of an access to object definition.
20714 -- It is correct to define double not-null pointers.
20717 -- type Not_Null_Int_Ptr is not null access Integer;
20718 -- type Acc is not null access Not_Null_Int_Ptr;
20720 and then Nkind (P) /= N_Access_To_Object_Definition
20722 if Can_Never_Be_Null (Entity (S)) then
20723 case Nkind (Related_Nod) is
20724 when N_Full_Type_Declaration =>
20725 if Nkind (Type_Definition (Related_Nod))
20726 in N_Array_Type_Definition
20730 (Component_Definition
20731 (Type_Definition (Related_Nod)));
20734 Subtype_Indication (Type_Definition (Related_Nod));
20737 when N_Subtype_Declaration =>
20738 Error_Node := Subtype_Indication (Related_Nod);
20740 when N_Object_Declaration =>
20741 Error_Node := Object_Definition (Related_Nod);
20743 when N_Component_Declaration =>
20745 Subtype_Indication (Component_Definition (Related_Nod));
20747 when N_Allocator =>
20748 Error_Node := Expression (Related_Nod);
20751 pragma Assert (False);
20752 Error_Node := Related_Nod;
20756 ("`NOT NULL` not allowed (& already excludes null)",
20762 Create_Null_Excluding_Itype
20764 Related_Nod => P));
20765 Set_Entity (S, Etype (S));
20770 -- Case of constraint present, so that we have an N_Subtype_Indication
20771 -- node (this node is created only if constraints are present).
20774 Find_Type (Subtype_Mark (S));
20776 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20778 (Nkind (Parent (S)) = N_Subtype_Declaration
20779 and then Is_Itype (Defining_Identifier (Parent (S))))
20781 Check_Incomplete (Subtype_Mark (S));
20785 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20787 -- Explicit subtype declaration case
20789 if Nkind (P) = N_Subtype_Declaration then
20790 Def_Id := Defining_Identifier (P);
20792 -- Explicit derived type definition case
20794 elsif Nkind (P) = N_Derived_Type_Definition then
20795 Def_Id := Defining_Identifier (Parent (P));
20797 -- Implicit case, the Def_Id must be created as an implicit type.
20798 -- The one exception arises in the case of concurrent types, array
20799 -- and access types, where other subsidiary implicit types may be
20800 -- created and must appear before the main implicit type. In these
20801 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20802 -- has not yet been called to create Def_Id.
20805 if Is_Array_Type (Subtype_Mark_Id)
20806 or else Is_Concurrent_Type (Subtype_Mark_Id)
20807 or else Is_Access_Type (Subtype_Mark_Id)
20811 -- For the other cases, we create a new unattached Itype,
20812 -- and set the indication to ensure it gets attached later.
20816 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20820 -- If the kind of constraint is invalid for this kind of type,
20821 -- then give an error, and then pretend no constraint was given.
20823 if not Is_Valid_Constraint_Kind
20824 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20827 ("incorrect constraint for this kind of type", Constraint (S));
20829 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20831 -- Set Ekind of orphan itype, to prevent cascaded errors
20833 if Present (Def_Id) then
20834 Set_Ekind (Def_Id, Ekind (Any_Type));
20837 -- Make recursive call, having got rid of the bogus constraint
20839 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20842 -- Remaining processing depends on type. Select on Base_Type kind to
20843 -- ensure getting to the concrete type kind in the case of a private
20844 -- subtype (needed when only doing semantic analysis).
20846 case Ekind (Base_Type (Subtype_Mark_Id)) is
20847 when Access_Kind =>
20849 -- If this is a constraint on a class-wide type, discard it.
20850 -- There is currently no way to express a partial discriminant
20851 -- constraint on a type with unknown discriminants. This is
20852 -- a pathology that the ACATS wisely decides not to test.
20854 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20855 if Comes_From_Source (S) then
20857 ("constraint on class-wide type ignored??",
20861 if Nkind (P) = N_Subtype_Declaration then
20862 Set_Subtype_Indication (P,
20863 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20866 return Subtype_Mark_Id;
20869 Constrain_Access (Def_Id, S, Related_Nod);
20872 and then Is_Itype (Designated_Type (Def_Id))
20873 and then Nkind (Related_Nod) = N_Subtype_Declaration
20874 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20876 Build_Itype_Reference
20877 (Designated_Type (Def_Id), Related_Nod);
20881 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20883 when Decimal_Fixed_Point_Kind =>
20884 Constrain_Decimal (Def_Id, S);
20886 when Enumeration_Kind =>
20887 Constrain_Enumeration (Def_Id, S);
20888 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20890 when Ordinary_Fixed_Point_Kind =>
20891 Constrain_Ordinary_Fixed (Def_Id, S);
20894 Constrain_Float (Def_Id, S);
20896 when Integer_Kind =>
20897 Constrain_Integer (Def_Id, S);
20898 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20900 when E_Record_Type |
20903 E_Incomplete_Type =>
20904 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20906 if Ekind (Def_Id) = E_Incomplete_Type then
20907 Set_Private_Dependents (Def_Id, New_Elmt_List);
20910 when Private_Kind =>
20911 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20913 -- The base type may be private but Def_Id may be a full view
20916 if Is_Private_Type (Def_Id) then
20917 Set_Private_Dependents (Def_Id, New_Elmt_List);
20920 -- In case of an invalid constraint prevent further processing
20921 -- since the type constructed is missing expected fields.
20923 if Etype (Def_Id) = Any_Type then
20927 -- If the full view is that of a task with discriminants,
20928 -- we must constrain both the concurrent type and its
20929 -- corresponding record type. Otherwise we will just propagate
20930 -- the constraint to the full view, if available.
20932 if Present (Full_View (Subtype_Mark_Id))
20933 and then Has_Discriminants (Subtype_Mark_Id)
20934 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20937 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20939 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20940 Constrain_Concurrent (Full_View_Id, S,
20941 Related_Nod, Related_Id, Suffix);
20942 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20943 Set_Full_View (Def_Id, Full_View_Id);
20945 -- Introduce an explicit reference to the private subtype,
20946 -- to prevent scope anomalies in gigi if first use appears
20947 -- in a nested context, e.g. a later function body.
20948 -- Should this be generated in other contexts than a full
20949 -- type declaration?
20951 if Is_Itype (Def_Id)
20953 Nkind (Parent (P)) = N_Full_Type_Declaration
20955 Build_Itype_Reference (Def_Id, Parent (P));
20959 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20962 when Concurrent_Kind =>
20963 Constrain_Concurrent (Def_Id, S,
20964 Related_Nod, Related_Id, Suffix);
20967 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20970 -- Size and Convention are always inherited from the base type
20972 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20973 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20977 end Process_Subtype;
20979 --------------------------------------------
20980 -- Propagate_Default_Init_Cond_Attributes --
20981 --------------------------------------------
20983 procedure Propagate_Default_Init_Cond_Attributes
20984 (From_Typ : Entity_Id;
20985 To_Typ : Entity_Id;
20986 Parent_To_Derivation : Boolean := False;
20987 Private_To_Full_View : Boolean := False)
20989 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20990 -- Remove the default initial condition procedure (if any) from the
20991 -- Subprograms_For_Type chain of type Typ.
20993 ----------------------------------------
20994 -- Remove_Default_Init_Cond_Procedure --
20995 ----------------------------------------
20997 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20998 Subps : constant Elist_Id := Subprograms_For_Type (Typ);
20999 Subp_Elmt : Elmt_Id;
21000 Subp_Id : Entity_Id;
21003 if Present (Subps) then
21004 Subp_Elmt := First_Elmt (Subps);
21005 while Present (Subp_Elmt) loop
21006 Subp_Id := Node (Subp_Elmt);
21008 if Is_Default_Init_Cond_Procedure (Subp_Id) then
21009 Remove_Elmt (Subps, Subp_Elmt);
21013 Next_Elmt (Subp_Elmt);
21016 end Remove_Default_Init_Cond_Procedure;
21020 Inherit_Procedure : Boolean := False;
21022 -- Start of processing for Propagate_Default_Init_Cond_Attributes
21025 if Has_Default_Init_Cond (From_Typ) then
21027 -- A derived type inherits the attributes from its parent type
21029 if Parent_To_Derivation then
21030 Set_Has_Inherited_Default_Init_Cond (To_Typ);
21032 -- A full view shares the attributes with its private view
21035 Set_Has_Default_Init_Cond (To_Typ);
21038 Inherit_Procedure := True;
21040 -- Due to the order of expansion, a derived private type is processed
21041 -- by two routines which both attempt to set the attributes related
21042 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
21043 -- Process_Full_View.
21046 -- type Parent_Typ is private
21047 -- with Default_Initial_Condition ...;
21049 -- type Parent_Typ is ...;
21052 -- with Pack; use Pack;
21053 -- package Pack_2 is
21054 -- type Deriv_Typ is private
21055 -- with Default_Initial_Condition ...;
21057 -- type Deriv_Typ is new Parent_Typ;
21060 -- When Build_Derived_Type operates, it sets the attributes on the
21061 -- full view without taking into account that the private view may
21062 -- define its own default initial condition procedure. This becomes
21063 -- apparent in Process_Full_View which must undo some of the work by
21064 -- Build_Derived_Type and propagate the attributes from the private
21065 -- to the full view.
21067 if Private_To_Full_View then
21068 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
21069 Remove_Default_Init_Cond_Procedure (To_Typ);
21072 -- A type must inherit the default initial condition procedure from a
21073 -- parent type when the parent itself is inheriting the procedure or
21074 -- when it is defining one. This circuitry is also used when dealing
21075 -- with the private / full view of a type.
21077 elsif Has_Inherited_Default_Init_Cond (From_Typ)
21078 or (Parent_To_Derivation
21079 and Present (Get_Pragma
21080 (From_Typ, Pragma_Default_Initial_Condition)))
21082 Set_Has_Inherited_Default_Init_Cond (To_Typ);
21083 Inherit_Procedure := True;
21086 if Inherit_Procedure
21087 and then No (Default_Init_Cond_Procedure (To_Typ))
21089 Set_Default_Init_Cond_Procedure
21090 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
21092 end Propagate_Default_Init_Cond_Attributes;
21094 -----------------------------
21095 -- Record_Type_Declaration --
21096 -----------------------------
21098 procedure Record_Type_Declaration
21103 Def : constant Node_Id := Type_Definition (N);
21104 Is_Tagged : Boolean;
21105 Tag_Comp : Entity_Id;
21108 -- These flags must be initialized before calling Process_Discriminants
21109 -- because this routine makes use of them.
21111 Set_Ekind (T, E_Record_Type);
21113 Init_Size_Align (T);
21114 Set_Interfaces (T, No_Elist);
21115 Set_Stored_Constraint (T, No_Elist);
21116 Set_Default_SSO (T);
21120 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
21121 if Limited_Present (Def) then
21122 Check_SPARK_05_Restriction ("limited is not allowed", N);
21125 if Abstract_Present (Def) then
21126 Check_SPARK_05_Restriction ("abstract is not allowed", N);
21129 -- The flag Is_Tagged_Type might have already been set by
21130 -- Find_Type_Name if it detected an error for declaration T. This
21131 -- arises in the case of private tagged types where the full view
21132 -- omits the word tagged.
21135 Tagged_Present (Def)
21136 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21138 Set_Is_Limited_Record (T, Limited_Present (Def));
21141 Set_Is_Tagged_Type (T, True);
21142 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21145 -- Type is abstract if full declaration carries keyword, or if
21146 -- previous partial view did.
21148 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21149 or else Abstract_Present (Def));
21152 Check_SPARK_05_Restriction ("interface is not allowed", N);
21155 Analyze_Interface_Declaration (T, Def);
21157 if Present (Discriminant_Specifications (N)) then
21159 ("interface types cannot have discriminants",
21160 Defining_Identifier
21161 (First (Discriminant_Specifications (N))));
21165 -- First pass: if there are self-referential access components,
21166 -- create the required anonymous access type declarations, and if
21167 -- need be an incomplete type declaration for T itself.
21169 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21171 if Ada_Version >= Ada_2005
21172 and then Present (Interface_List (Def))
21174 Check_Interfaces (N, Def);
21177 Ifaces_List : Elist_Id;
21180 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21181 -- already in the parents.
21185 Ifaces_List => Ifaces_List,
21186 Exclude_Parents => True);
21188 Set_Interfaces (T, Ifaces_List);
21192 -- Records constitute a scope for the component declarations within.
21193 -- The scope is created prior to the processing of these declarations.
21194 -- Discriminants are processed first, so that they are visible when
21195 -- processing the other components. The Ekind of the record type itself
21196 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21198 -- Enter record scope
21202 -- If an incomplete or private type declaration was already given for
21203 -- the type, then this scope already exists, and the discriminants have
21204 -- been declared within. We must verify that the full declaration
21205 -- matches the incomplete one.
21207 Check_Or_Process_Discriminants (N, T, Prev);
21209 Set_Is_Constrained (T, not Has_Discriminants (T));
21210 Set_Has_Delayed_Freeze (T, True);
21212 -- For tagged types add a manually analyzed component corresponding
21213 -- to the component _tag, the corresponding piece of tree will be
21214 -- expanded as part of the freezing actions if it is not a CPP_Class.
21218 -- Do not add the tag unless we are in expansion mode
21220 if Expander_Active then
21221 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21222 Enter_Name (Tag_Comp);
21224 Set_Ekind (Tag_Comp, E_Component);
21225 Set_Is_Tag (Tag_Comp);
21226 Set_Is_Aliased (Tag_Comp);
21227 Set_Etype (Tag_Comp, RTE (RE_Tag));
21228 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21229 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21230 Init_Component_Location (Tag_Comp);
21232 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21233 -- implemented interfaces.
21235 if Has_Interfaces (T) then
21236 Add_Interface_Tag_Components (N, T);
21240 Make_Class_Wide_Type (T);
21241 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21244 -- We must suppress range checks when processing record components in
21245 -- the presence of discriminants, since we don't want spurious checks to
21246 -- be generated during their analysis, but Suppress_Range_Checks flags
21247 -- must be reset the after processing the record definition.
21249 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21250 -- couldn't we just use the normal range check suppression method here.
21251 -- That would seem cleaner ???
21253 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21254 Set_Kill_Range_Checks (T, True);
21255 Record_Type_Definition (Def, Prev);
21256 Set_Kill_Range_Checks (T, False);
21258 Record_Type_Definition (Def, Prev);
21261 -- Exit from record scope
21265 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21266 -- the implemented interfaces and associate them an aliased entity.
21269 and then not Is_Empty_List (Interface_List (Def))
21271 Derive_Progenitor_Subprograms (T, T);
21274 Check_Function_Writable_Actuals (N);
21275 end Record_Type_Declaration;
21277 ----------------------------
21278 -- Record_Type_Definition --
21279 ----------------------------
21281 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21282 Component : Entity_Id;
21283 Ctrl_Components : Boolean := False;
21284 Final_Storage_Only : Boolean;
21288 if Ekind (Prev_T) = E_Incomplete_Type then
21289 T := Full_View (Prev_T);
21294 -- In SPARK, tagged types and type extensions may only be declared in
21295 -- the specification of library unit packages.
21297 if Present (Def) and then Is_Tagged_Type (T) then
21303 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21304 Typ := Parent (Def);
21307 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21308 Typ := Parent (Parent (Def));
21311 Ctxt := Parent (Typ);
21313 if Nkind (Ctxt) = N_Package_Body
21314 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21316 Check_SPARK_05_Restriction
21317 ("type should be defined in package specification", Typ);
21319 elsif Nkind (Ctxt) /= N_Package_Specification
21320 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21322 Check_SPARK_05_Restriction
21323 ("type should be defined in library unit package", Typ);
21328 Final_Storage_Only := not Is_Controlled_Active (T);
21330 -- Ada 2005: Check whether an explicit Limited is present in a derived
21331 -- type declaration.
21333 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21334 and then Limited_Present (Parent (Def))
21336 Set_Is_Limited_Record (T);
21339 -- If the component list of a record type is defined by the reserved
21340 -- word null and there is no discriminant part, then the record type has
21341 -- no components and all records of the type are null records (RM 3.7)
21342 -- This procedure is also called to process the extension part of a
21343 -- record extension, in which case the current scope may have inherited
21347 or else No (Component_List (Def))
21348 or else Null_Present (Component_List (Def))
21350 if not Is_Tagged_Type (T) then
21351 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21355 Analyze_Declarations (Component_Items (Component_List (Def)));
21357 if Present (Variant_Part (Component_List (Def))) then
21358 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21359 Analyze (Variant_Part (Component_List (Def)));
21363 -- After completing the semantic analysis of the record definition,
21364 -- record components, both new and inherited, are accessible. Set their
21365 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21366 -- whose Ekind may be void.
21368 Component := First_Entity (Current_Scope);
21369 while Present (Component) loop
21370 if Ekind (Component) = E_Void
21371 and then not Is_Itype (Component)
21373 Set_Ekind (Component, E_Component);
21374 Init_Component_Location (Component);
21377 Propagate_Concurrent_Flags (T, Etype (Component));
21379 if Ekind (Component) /= E_Component then
21382 -- Do not set Has_Controlled_Component on a class-wide equivalent
21383 -- type. See Make_CW_Equivalent_Type.
21385 elsif not Is_Class_Wide_Equivalent_Type (T)
21386 and then (Has_Controlled_Component (Etype (Component))
21387 or else (Chars (Component) /= Name_uParent
21388 and then Is_Controlled_Active
21389 (Etype (Component))))
21391 Set_Has_Controlled_Component (T, True);
21392 Final_Storage_Only :=
21394 and then Finalize_Storage_Only (Etype (Component));
21395 Ctrl_Components := True;
21398 Next_Entity (Component);
21401 -- A Type is Finalize_Storage_Only only if all its controlled components
21404 if Ctrl_Components then
21405 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21408 -- Place reference to end record on the proper entity, which may
21409 -- be a partial view.
21411 if Present (Def) then
21412 Process_End_Label (Def, 'e', Prev_T);
21414 end Record_Type_Definition;
21416 ------------------------
21417 -- Replace_Components --
21418 ------------------------
21420 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21421 function Process (N : Node_Id) return Traverse_Result;
21427 function Process (N : Node_Id) return Traverse_Result is
21431 if Nkind (N) = N_Discriminant_Specification then
21432 Comp := First_Discriminant (Typ);
21433 while Present (Comp) loop
21434 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21435 Set_Defining_Identifier (N, Comp);
21439 Next_Discriminant (Comp);
21442 elsif Nkind (N) = N_Component_Declaration then
21443 Comp := First_Component (Typ);
21444 while Present (Comp) loop
21445 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21446 Set_Defining_Identifier (N, Comp);
21450 Next_Component (Comp);
21457 procedure Replace is new Traverse_Proc (Process);
21459 -- Start of processing for Replace_Components
21463 end Replace_Components;
21465 -------------------------------
21466 -- Set_Completion_Referenced --
21467 -------------------------------
21469 procedure Set_Completion_Referenced (E : Entity_Id) is
21471 -- If in main unit, mark entity that is a completion as referenced,
21472 -- warnings go on the partial view when needed.
21474 if In_Extended_Main_Source_Unit (E) then
21475 Set_Referenced (E);
21477 end Set_Completion_Referenced;
21479 ---------------------
21480 -- Set_Default_SSO --
21481 ---------------------
21483 procedure Set_Default_SSO (T : Entity_Id) is
21485 case Opt.Default_SSO is
21489 Set_SSO_Set_Low_By_Default (T, True);
21491 Set_SSO_Set_High_By_Default (T, True);
21493 raise Program_Error;
21495 end Set_Default_SSO;
21497 ---------------------
21498 -- Set_Fixed_Range --
21499 ---------------------
21501 -- The range for fixed-point types is complicated by the fact that we
21502 -- do not know the exact end points at the time of the declaration. This
21503 -- is true for three reasons:
21505 -- A size clause may affect the fudging of the end-points.
21506 -- A small clause may affect the values of the end-points.
21507 -- We try to include the end-points if it does not affect the size.
21509 -- This means that the actual end-points must be established at the
21510 -- point when the type is frozen. Meanwhile, we first narrow the range
21511 -- as permitted (so that it will fit if necessary in a small specified
21512 -- size), and then build a range subtree with these narrowed bounds.
21513 -- Set_Fixed_Range constructs the range from real literal values, and
21514 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21516 -- The parent of this range is set to point to the entity so that it is
21517 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21518 -- other scalar types, which are just pointers to the range in the
21519 -- original tree, this would otherwise be an orphan).
21521 -- The tree is left unanalyzed. When the type is frozen, the processing
21522 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21523 -- analyzed, and uses this as an indication that it should complete
21524 -- work on the range (it will know the final small and size values).
21526 procedure Set_Fixed_Range
21532 S : constant Node_Id :=
21534 Low_Bound => Make_Real_Literal (Loc, Lo),
21535 High_Bound => Make_Real_Literal (Loc, Hi));
21537 Set_Scalar_Range (E, S);
21540 -- Before the freeze point, the bounds of a fixed point are universal
21541 -- and carry the corresponding type.
21543 Set_Etype (Low_Bound (S), Universal_Real);
21544 Set_Etype (High_Bound (S), Universal_Real);
21545 end Set_Fixed_Range;
21547 ----------------------------------
21548 -- Set_Scalar_Range_For_Subtype --
21549 ----------------------------------
21551 procedure Set_Scalar_Range_For_Subtype
21552 (Def_Id : Entity_Id;
21556 Kind : constant Entity_Kind := Ekind (Def_Id);
21559 -- Defend against previous error
21561 if Nkind (R) = N_Error then
21565 Set_Scalar_Range (Def_Id, R);
21567 -- We need to link the range into the tree before resolving it so
21568 -- that types that are referenced, including importantly the subtype
21569 -- itself, are properly frozen (Freeze_Expression requires that the
21570 -- expression be properly linked into the tree). Of course if it is
21571 -- already linked in, then we do not disturb the current link.
21573 if No (Parent (R)) then
21574 Set_Parent (R, Def_Id);
21577 -- Reset the kind of the subtype during analysis of the range, to
21578 -- catch possible premature use in the bounds themselves.
21580 Set_Ekind (Def_Id, E_Void);
21581 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21582 Set_Ekind (Def_Id, Kind);
21583 end Set_Scalar_Range_For_Subtype;
21585 --------------------------------------------------------
21586 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21587 --------------------------------------------------------
21589 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21593 -- Make sure set if encountered during Expand_To_Stored_Constraint
21595 Set_Stored_Constraint (E, No_Elist);
21597 -- Give it the right value
21599 if Is_Constrained (E) and then Has_Discriminants (E) then
21600 Set_Stored_Constraint (E,
21601 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21603 end Set_Stored_Constraint_From_Discriminant_Constraint;
21605 -------------------------------------
21606 -- Signed_Integer_Type_Declaration --
21607 -------------------------------------
21609 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21610 Implicit_Base : Entity_Id;
21611 Base_Typ : Entity_Id;
21614 Errs : Boolean := False;
21618 function Can_Derive_From (E : Entity_Id) return Boolean;
21619 -- Determine whether given bounds allow derivation from specified type
21621 procedure Check_Bound (Expr : Node_Id);
21622 -- Check bound to make sure it is integral and static. If not, post
21623 -- appropriate error message and set Errs flag
21625 ---------------------
21626 -- Can_Derive_From --
21627 ---------------------
21629 -- Note we check both bounds against both end values, to deal with
21630 -- strange types like ones with a range of 0 .. -12341234.
21632 function Can_Derive_From (E : Entity_Id) return Boolean is
21633 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21634 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21636 return Lo <= Lo_Val and then Lo_Val <= Hi
21638 Lo <= Hi_Val and then Hi_Val <= Hi;
21639 end Can_Derive_From;
21645 procedure Check_Bound (Expr : Node_Id) is
21647 -- If a range constraint is used as an integer type definition, each
21648 -- bound of the range must be defined by a static expression of some
21649 -- integer type, but the two bounds need not have the same integer
21650 -- type (Negative bounds are allowed.) (RM 3.5.4)
21652 if not Is_Integer_Type (Etype (Expr)) then
21654 ("integer type definition bounds must be of integer type", Expr);
21657 elsif not Is_OK_Static_Expression (Expr) then
21658 Flag_Non_Static_Expr
21659 ("non-static expression used for integer type bound!", Expr);
21662 -- The bounds are folded into literals, and we set their type to be
21663 -- universal, to avoid typing difficulties: we cannot set the type
21664 -- of the literal to the new type, because this would be a forward
21665 -- reference for the back end, and if the original type is user-
21666 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21669 if Is_Entity_Name (Expr) then
21670 Fold_Uint (Expr, Expr_Value (Expr), True);
21673 Set_Etype (Expr, Universal_Integer);
21677 -- Start of processing for Signed_Integer_Type_Declaration
21680 -- Create an anonymous base type
21683 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21685 -- Analyze and check the bounds, they can be of any integer type
21687 Lo := Low_Bound (Def);
21688 Hi := High_Bound (Def);
21690 -- Arbitrarily use Integer as the type if either bound had an error
21692 if Hi = Error or else Lo = Error then
21693 Base_Typ := Any_Integer;
21694 Set_Error_Posted (T, True);
21696 -- Here both bounds are OK expressions
21699 Analyze_And_Resolve (Lo, Any_Integer);
21700 Analyze_And_Resolve (Hi, Any_Integer);
21706 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21707 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21710 -- Find type to derive from
21712 Lo_Val := Expr_Value (Lo);
21713 Hi_Val := Expr_Value (Hi);
21715 if Can_Derive_From (Standard_Short_Short_Integer) then
21716 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21718 elsif Can_Derive_From (Standard_Short_Integer) then
21719 Base_Typ := Base_Type (Standard_Short_Integer);
21721 elsif Can_Derive_From (Standard_Integer) then
21722 Base_Typ := Base_Type (Standard_Integer);
21724 elsif Can_Derive_From (Standard_Long_Integer) then
21725 Base_Typ := Base_Type (Standard_Long_Integer);
21727 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21728 Check_Restriction (No_Long_Long_Integers, Def);
21729 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21732 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21733 Error_Msg_N ("integer type definition bounds out of range", Def);
21734 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21735 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21739 -- Complete both implicit base and declared first subtype entities. The
21740 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21741 -- are not clobbered when the signed integer type acts as a full view of
21744 Set_Etype (Implicit_Base, Base_Typ);
21745 Set_Size_Info (Implicit_Base, Base_Typ);
21746 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21747 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21748 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21750 Set_Ekind (T, E_Signed_Integer_Subtype);
21751 Set_Etype (T, Implicit_Base);
21752 Set_Size_Info (T, Implicit_Base);
21753 Inherit_Rep_Item_Chain (T, Implicit_Base);
21754 Set_Scalar_Range (T, Def);
21755 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21756 Set_Is_Constrained (T);
21757 end Signed_Integer_Type_Declaration;