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996ae0b0 RK |
1 | ------------------------------------------------------------------------------ |
2 | -- -- | |
3 | -- GNAT COMPILER COMPONENTS -- | |
4 | -- -- | |
5 | -- S E M _ D I S P -- | |
6 | -- -- | |
7 | -- B o d y -- | |
8 | -- -- | |
4b490c1e | 9 | -- Copyright (C) 1992-2020, Free Software Foundation, Inc. -- |
996ae0b0 RK |
10 | -- -- |
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- -- | |
b5c84c3c | 13 | -- ware Foundation; either version 3, or (at your option) any later ver- -- |
996ae0b0 RK |
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 -- | |
b5c84c3c RD |
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. -- | |
996ae0b0 RK |
20 | -- -- |
21 | -- GNAT was originally developed by the GNAT team at New York University. -- | |
71ff80dc | 22 | -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
996ae0b0 RK |
23 | -- -- |
24 | ------------------------------------------------------------------------------ | |
25 | ||
26 | with Atree; use Atree; | |
27 | with Debug; use Debug; | |
28 | with Elists; use Elists; | |
29 | with Einfo; use Einfo; | |
30 | with Exp_Disp; use Exp_Disp; | |
991395ab | 31 | with Exp_Util; use Exp_Util; |
07fc65c4 GB |
32 | with Exp_Ch7; use Exp_Ch7; |
33 | with Exp_Tss; use Exp_Tss; | |
996ae0b0 | 34 | with Errout; use Errout; |
f7d5442e | 35 | with Lib.Xref; use Lib.Xref; |
8909e1ed | 36 | with Namet; use Namet; |
996ae0b0 | 37 | with Nlists; use Nlists; |
82c80734 | 38 | with Nmake; use Nmake; |
07fc65c4 | 39 | with Opt; use Opt; |
996ae0b0 | 40 | with Output; use Output; |
3bcd6930 JM |
41 | with Restrict; use Restrict; |
42 | with Rident; use Rident; | |
07fc65c4 | 43 | with Sem; use Sem; |
a4100e55 | 44 | with Sem_Aux; use Sem_Aux; |
26a43556 | 45 | with Sem_Ch3; use Sem_Ch3; |
996ae0b0 | 46 | with Sem_Ch6; use Sem_Ch6; |
57081559 | 47 | with Sem_Ch8; use Sem_Ch8; |
996ae0b0 | 48 | with Sem_Eval; use Sem_Eval; |
82c80734 | 49 | with Sem_Type; use Sem_Type; |
996ae0b0 | 50 | with Sem_Util; use Sem_Util; |
07fc65c4 | 51 | with Snames; use Snames; |
996ae0b0 | 52 | with Sinfo; use Sinfo; |
82c80734 | 53 | with Tbuild; use Tbuild; |
996ae0b0 | 54 | with Uintp; use Uintp; |
48c8c473 | 55 | with Warnsw; use Warnsw; |
996ae0b0 RK |
56 | |
57 | package body Sem_Disp is | |
58 | ||
59 | ----------------------- | |
60 | -- Local Subprograms -- | |
61 | ----------------------- | |
62 | ||
996ae0b0 RK |
63 | procedure Add_Dispatching_Operation |
64 | (Tagged_Type : Entity_Id; | |
65 | New_Op : Entity_Id); | |
66 | -- Add New_Op in the list of primitive operations of Tagged_Type | |
67 | ||
68 | function Check_Controlling_Type | |
69 | (T : Entity_Id; | |
15ce9ca2 | 70 | Subp : Entity_Id) return Entity_Id; |
82c80734 RD |
71 | -- T is the tagged type of a formal parameter or the result of Subp. |
72 | -- If the subprogram has a controlling parameter or result that matches | |
73 | -- the type, then returns the tagged type of that parameter or result | |
74 | -- (returning the designated tagged type in the case of an access | |
75 | -- parameter); otherwise returns empty. | |
996ae0b0 | 76 | |
ea034236 AC |
77 | function Find_Hidden_Overridden_Primitive (S : Entity_Id) return Entity_Id; |
78 | -- [Ada 2012:AI-0125] Find an inherited hidden primitive of the dispatching | |
79 | -- type of S that has the same name of S, a type-conformant profile, an | |
80 | -- original corresponding operation O that is a primitive of a visible | |
81 | -- ancestor of the dispatching type of S and O is visible at the point of | |
82 | -- of declaration of S. If the entity is found the Alias of S is set to the | |
83 | -- original corresponding operation S and its Overridden_Operation is set | |
84 | -- to the found entity; otherwise return Empty. | |
85 | -- | |
86 | -- This routine does not search for non-hidden primitives since they are | |
87 | -- covered by the normal Ada 2005 rules. | |
88 | ||
7b4ebba5 AC |
89 | function Is_Inherited_Public_Operation (Op : Entity_Id) return Boolean; |
90 | -- Check whether a primitive operation is inherited from an operation | |
91 | -- declared in the visible part of its package. | |
92 | ||
15ce9ca2 AC |
93 | ------------------------------- |
94 | -- Add_Dispatching_Operation -- | |
95 | ------------------------------- | |
996ae0b0 RK |
96 | |
97 | procedure Add_Dispatching_Operation | |
98 | (Tagged_Type : Entity_Id; | |
99 | New_Op : Entity_Id) | |
100 | is | |
101 | List : constant Elist_Id := Primitive_Operations (Tagged_Type); | |
20e8cdd7 | 102 | |
996ae0b0 | 103 | begin |
550f4135 AC |
104 | -- The dispatching operation may already be on the list, if it is the |
105 | -- wrapper for an inherited function of a null extension (see Exp_Ch3 | |
20e8cdd7 GD |
106 | -- for the construction of function wrappers). The list of primitive |
107 | -- operations must not contain duplicates. | |
108 | ||
9057bd6a HK |
109 | -- The Default_Initial_Condition and invariant procedures are not added |
110 | -- to the list of primitives even when they are generated for a tagged | |
111 | -- type. These routines must not be targets of dispatching calls and | |
112 | -- therefore must not appear in the dispatch table because they already | |
113 | -- utilize class-wide-precondition semantics to handle inheritance and | |
114 | -- overriding. | |
115 | ||
116 | if Is_Suitable_Primitive (New_Op) then | |
117 | Append_Unique_Elmt (New_Op, List); | |
118 | end if; | |
996ae0b0 RK |
119 | end Add_Dispatching_Operation; |
120 | ||
904a2ae4 AC |
121 | -------------------------- |
122 | -- Covered_Interface_Op -- | |
123 | -------------------------- | |
0052da20 | 124 | |
904a2ae4 | 125 | function Covered_Interface_Op (Prim : Entity_Id) return Entity_Id is |
0052da20 JM |
126 | Tagged_Type : constant Entity_Id := Find_Dispatching_Type (Prim); |
127 | Elmt : Elmt_Id; | |
128 | E : Entity_Id; | |
129 | ||
130 | begin | |
131 | pragma Assert (Is_Dispatching_Operation (Prim)); | |
132 | ||
133 | -- Although this is a dispatching primitive we must check if its | |
134 | -- dispatching type is available because it may be the primitive | |
135 | -- of a private type not defined as tagged in its partial view. | |
136 | ||
137 | if Present (Tagged_Type) and then Has_Interfaces (Tagged_Type) then | |
138 | ||
139 | -- If the tagged type is frozen then the internal entities associated | |
140 | -- with interfaces are available in the list of primitives of the | |
141 | -- tagged type and can be used to speed up this search. | |
142 | ||
143 | if Is_Frozen (Tagged_Type) then | |
144 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); | |
145 | while Present (Elmt) loop | |
146 | E := Node (Elmt); | |
147 | ||
148 | if Present (Interface_Alias (E)) | |
149 | and then Alias (E) = Prim | |
150 | then | |
904a2ae4 | 151 | return Interface_Alias (E); |
0052da20 JM |
152 | end if; |
153 | ||
154 | Next_Elmt (Elmt); | |
155 | end loop; | |
156 | ||
157 | -- Otherwise we must collect all the interface primitives and check | |
904a2ae4 | 158 | -- if the Prim overrides (implements) some interface primitive. |
0052da20 JM |
159 | |
160 | else | |
161 | declare | |
162 | Ifaces_List : Elist_Id; | |
163 | Iface_Elmt : Elmt_Id; | |
164 | Iface : Entity_Id; | |
165 | Iface_Prim : Entity_Id; | |
166 | ||
167 | begin | |
168 | Collect_Interfaces (Tagged_Type, Ifaces_List); | |
169 | Iface_Elmt := First_Elmt (Ifaces_List); | |
170 | while Present (Iface_Elmt) loop | |
171 | Iface := Node (Iface_Elmt); | |
172 | ||
173 | Elmt := First_Elmt (Primitive_Operations (Iface)); | |
174 | while Present (Elmt) loop | |
175 | Iface_Prim := Node (Elmt); | |
176 | ||
904a2ae4 | 177 | if Chars (Iface_Prim) = Chars (Prim) |
0052da20 JM |
178 | and then Is_Interface_Conformant |
179 | (Tagged_Type, Iface_Prim, Prim) | |
180 | then | |
904a2ae4 | 181 | return Iface_Prim; |
0052da20 JM |
182 | end if; |
183 | ||
184 | Next_Elmt (Elmt); | |
185 | end loop; | |
186 | ||
187 | Next_Elmt (Iface_Elmt); | |
188 | end loop; | |
189 | end; | |
190 | end if; | |
191 | end if; | |
192 | ||
904a2ae4 AC |
193 | return Empty; |
194 | end Covered_Interface_Op; | |
0052da20 | 195 | |
996ae0b0 RK |
196 | ------------------------------- |
197 | -- Check_Controlling_Formals -- | |
198 | ------------------------------- | |
199 | ||
200 | procedure Check_Controlling_Formals | |
201 | (Typ : Entity_Id; | |
202 | Subp : Entity_Id) | |
203 | is | |
204 | Formal : Entity_Id; | |
205 | Ctrl_Type : Entity_Id; | |
996ae0b0 RK |
206 | |
207 | begin | |
208 | Formal := First_Formal (Subp); | |
996ae0b0 RK |
209 | while Present (Formal) loop |
210 | Ctrl_Type := Check_Controlling_Type (Etype (Formal), Subp); | |
211 | ||
212 | if Present (Ctrl_Type) then | |
eedc5882 | 213 | |
e3a79ce3 JS |
214 | -- Obtain the full type in case we are looking at an incomplete |
215 | -- view. | |
216 | ||
217 | if Ekind (Ctrl_Type) = E_Incomplete_Type | |
218 | and then Present (Full_View (Ctrl_Type)) | |
219 | then | |
220 | Ctrl_Type := Full_View (Ctrl_Type); | |
221 | end if; | |
8909e1ed | 222 | |
0e41a941 AC |
223 | -- When controlling type is concurrent and declared within a |
224 | -- generic or inside an instance use corresponding record type. | |
8909e1ed JM |
225 | |
226 | if Is_Concurrent_Type (Ctrl_Type) | |
227 | and then Present (Corresponding_Record_Type (Ctrl_Type)) | |
228 | then | |
229 | Ctrl_Type := Corresponding_Record_Type (Ctrl_Type); | |
230 | end if; | |
231 | ||
996ae0b0 RK |
232 | if Ctrl_Type = Typ then |
233 | Set_Is_Controlling_Formal (Formal); | |
234 | ||
0e41a941 | 235 | -- Ada 2005 (AI-231): Anonymous access types that are used in |
67f3c450 HK |
236 | -- controlling parameters exclude null because it is necessary |
237 | -- to read the tag to dispatch, and null has no tag. | |
9cca32af JM |
238 | |
239 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then | |
240 | Set_Can_Never_Be_Null (Etype (Formal)); | |
241 | Set_Is_Known_Non_Null (Etype (Formal)); | |
242 | end if; | |
243 | ||
996ae0b0 RK |
244 | -- Check that the parameter's nominal subtype statically |
245 | -- matches the first subtype. | |
246 | ||
247 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then | |
248 | if not Subtypes_Statically_Match | |
249 | (Typ, Designated_Type (Etype (Formal))) | |
250 | then | |
251 | Error_Msg_N | |
252 | ("parameter subtype does not match controlling type", | |
253 | Formal); | |
254 | end if; | |
255 | ||
6eca51ce ES |
256 | -- Within a predicate function, the formal may be a subtype |
257 | -- of a tagged type, given that the predicate is expressed | |
258 | -- in terms of the subtype. | |
259 | ||
260 | elsif not Subtypes_Statically_Match (Typ, Etype (Formal)) | |
261 | and then not Is_Predicate_Function (Subp) | |
262 | then | |
996ae0b0 RK |
263 | Error_Msg_N |
264 | ("parameter subtype does not match controlling type", | |
265 | Formal); | |
266 | end if; | |
267 | ||
268 | if Present (Default_Value (Formal)) then | |
20e8cdd7 GD |
269 | |
270 | -- In Ada 2005, access parameters can have defaults | |
271 | ||
272 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type | |
0791fbe9 | 273 | and then Ada_Version < Ada_2005 |
20e8cdd7 | 274 | then |
996ae0b0 RK |
275 | Error_Msg_N |
276 | ("default not allowed for controlling access parameter", | |
277 | Default_Value (Formal)); | |
278 | ||
279 | elsif not Is_Tag_Indeterminate (Default_Value (Formal)) then | |
280 | Error_Msg_N | |
281 | ("default expression must be a tag indeterminate" & | |
282 | " function call", Default_Value (Formal)); | |
283 | end if; | |
284 | end if; | |
285 | ||
286 | elsif Comes_From_Source (Subp) then | |
287 | Error_Msg_N | |
288 | ("operation can be dispatching in only one type", Subp); | |
289 | end if; | |
996ae0b0 RK |
290 | end if; |
291 | ||
292 | Next_Formal (Formal); | |
293 | end loop; | |
294 | ||
e1b871e9 | 295 | if Ekind_In (Subp, E_Function, E_Generic_Function) then |
996ae0b0 RK |
296 | Ctrl_Type := Check_Controlling_Type (Etype (Subp), Subp); |
297 | ||
298 | if Present (Ctrl_Type) then | |
299 | if Ctrl_Type = Typ then | |
300 | Set_Has_Controlling_Result (Subp); | |
301 | ||
67f3c450 | 302 | -- Check that result subtype statically matches first subtype |
550f4135 | 303 | -- (Ada 2005): Subp may have a controlling access result. |
996ae0b0 | 304 | |
8909e1ed JM |
305 | if Subtypes_Statically_Match (Typ, Etype (Subp)) |
306 | or else (Ekind (Etype (Subp)) = E_Anonymous_Access_Type | |
307 | and then | |
308 | Subtypes_Statically_Match | |
309 | (Typ, Designated_Type (Etype (Subp)))) | |
310 | then | |
311 | null; | |
312 | ||
313 | else | |
996ae0b0 RK |
314 | Error_Msg_N |
315 | ("result subtype does not match controlling type", Subp); | |
316 | end if; | |
317 | ||
318 | elsif Comes_From_Source (Subp) then | |
319 | Error_Msg_N | |
320 | ("operation can be dispatching in only one type", Subp); | |
321 | end if; | |
996ae0b0 RK |
322 | end if; |
323 | end if; | |
324 | end Check_Controlling_Formals; | |
325 | ||
326 | ---------------------------- | |
327 | -- Check_Controlling_Type -- | |
328 | ---------------------------- | |
329 | ||
330 | function Check_Controlling_Type | |
331 | (T : Entity_Id; | |
15ce9ca2 | 332 | Subp : Entity_Id) return Entity_Id |
996ae0b0 RK |
333 | is |
334 | Tagged_Type : Entity_Id := Empty; | |
335 | ||
336 | begin | |
337 | if Is_Tagged_Type (T) then | |
338 | if Is_First_Subtype (T) then | |
339 | Tagged_Type := T; | |
340 | else | |
341 | Tagged_Type := Base_Type (T); | |
342 | end if; | |
343 | ||
ec6cfc5d AC |
344 | -- If the type is incomplete, it may have been declared without a |
345 | -- Tagged indication, but the full view may be tagged, in which case | |
346 | -- that is the controlling type of the subprogram. This is one of the | |
347 | -- approx. 579 places in the language where a lookahead would help. | |
348 | ||
349 | elsif Ekind (T) = E_Incomplete_Type | |
350 | and then Present (Full_View (T)) | |
351 | and then Is_Tagged_Type (Full_View (T)) | |
352 | then | |
353 | Set_Is_Tagged_Type (T); | |
354 | Tagged_Type := Full_View (T); | |
355 | ||
996ae0b0 RK |
356 | elsif Ekind (T) = E_Anonymous_Access_Type |
357 | and then Is_Tagged_Type (Designated_Type (T)) | |
996ae0b0 | 358 | then |
758c442c GD |
359 | if Ekind (Designated_Type (T)) /= E_Incomplete_Type then |
360 | if Is_First_Subtype (Designated_Type (T)) then | |
361 | Tagged_Type := Designated_Type (T); | |
362 | else | |
363 | Tagged_Type := Base_Type (Designated_Type (T)); | |
364 | end if; | |
365 | ||
550f4135 AC |
366 | -- Ada 2005: an incomplete type can be tagged. An operation with an |
367 | -- access parameter of the type is dispatching. | |
dee4682a JM |
368 | |
369 | elsif Scope (Designated_Type (T)) = Current_Scope then | |
370 | Tagged_Type := Designated_Type (T); | |
371 | ||
758c442c GD |
372 | -- Ada 2005 (AI-50217) |
373 | ||
7b56a91b | 374 | elsif From_Limited_With (Designated_Type (T)) |
47346923 | 375 | and then Has_Non_Limited_View (Designated_Type (T)) |
477cfc5b | 376 | and then Scope (Designated_Type (T)) = Scope (Subp) |
758c442c GD |
377 | then |
378 | if Is_First_Subtype (Non_Limited_View (Designated_Type (T))) then | |
379 | Tagged_Type := Non_Limited_View (Designated_Type (T)); | |
380 | else | |
381 | Tagged_Type := Base_Type (Non_Limited_View | |
382 | (Designated_Type (T))); | |
383 | end if; | |
996ae0b0 RK |
384 | end if; |
385 | end if; | |
386 | ||
550f4135 | 387 | if No (Tagged_Type) or else Is_Class_Wide_Type (Tagged_Type) then |
996ae0b0 RK |
388 | return Empty; |
389 | ||
550f4135 AC |
390 | -- The dispatching type and the primitive operation must be defined in |
391 | -- the same scope, except in the case of internal operations and formal | |
392 | -- abstract subprograms. | |
996ae0b0 | 393 | |
82c80734 RD |
394 | elsif ((Scope (Subp) = Scope (Tagged_Type) or else Is_Internal (Subp)) |
395 | and then (not Is_Generic_Type (Tagged_Type) | |
396 | or else not Comes_From_Source (Subp))) | |
397 | or else | |
dee4682a | 398 | (Is_Formal_Subprogram (Subp) and then Is_Abstract_Subprogram (Subp)) |
82c80734 RD |
399 | or else |
400 | (Nkind (Parent (Parent (Subp))) = N_Subprogram_Renaming_Declaration | |
401 | and then | |
402 | Present (Corresponding_Formal_Spec (Parent (Parent (Subp)))) | |
403 | and then | |
dee4682a | 404 | Is_Abstract_Subprogram (Subp)) |
996ae0b0 RK |
405 | then |
406 | return Tagged_Type; | |
407 | ||
408 | else | |
409 | return Empty; | |
410 | end if; | |
411 | end Check_Controlling_Type; | |
412 | ||
413 | ---------------------------- | |
414 | -- Check_Dispatching_Call -- | |
415 | ---------------------------- | |
416 | ||
417 | procedure Check_Dispatching_Call (N : Node_Id) is | |
8909e1ed | 418 | Loc : constant Source_Ptr := Sloc (N); |
82c80734 RD |
419 | Actual : Node_Id; |
420 | Formal : Entity_Id; | |
421 | Control : Node_Id := Empty; | |
422 | Func : Entity_Id; | |
423 | Subp_Entity : Entity_Id; | |
82c80734 | 424 | Indeterm_Ancestor_Call : Boolean := False; |
5612989e | 425 | Indeterm_Ctrl_Type : Entity_Id := Empty; -- init to avoid warning |
996ae0b0 | 426 | |
d215a13c ES |
427 | Static_Tag : Node_Id := Empty; |
428 | -- If a controlling formal has a statically tagged actual, the tag of | |
550f4135 | 429 | -- this actual is to be used for any tag-indeterminate actual. |
d215a13c | 430 | |
4f91a255 AC |
431 | procedure Check_Direct_Call; |
432 | -- In the case when the controlling actual is a class-wide type whose | |
433 | -- root type's completion is a task or protected type, the call is in | |
434 | -- fact direct. This routine detects the above case and modifies the | |
435 | -- call accordingly. | |
436 | ||
0d66b596 | 437 | procedure Check_Dispatching_Context (Call : Node_Id); |
996ae0b0 RK |
438 | -- If the call is tag-indeterminate and the entity being called is |
439 | -- abstract, verify that the context is a call that will eventually | |
440 | -- provide a tag for dispatching, or has provided one already. | |
441 | ||
4f91a255 AC |
442 | ----------------------- |
443 | -- Check_Direct_Call -- | |
444 | ----------------------- | |
445 | ||
446 | procedure Check_Direct_Call is | |
447 | Typ : Entity_Id := Etype (Control); | |
4f91a255 | 448 | begin |
03456e44 AC |
449 | -- Predefined primitives do not receive wrappers since they are built |
450 | -- from scratch for the corresponding record of synchronized types. | |
451 | -- Equality is in general predefined, but is excluded from the check | |
452 | -- when it is user-defined. | |
453 | ||
454 | if Is_Predefined_Dispatching_Operation (Subp_Entity) | |
455 | and then not Is_User_Defined_Equality (Subp_Entity) | |
456 | then | |
457 | return; | |
458 | end if; | |
459 | ||
4f91a255 AC |
460 | if Is_Class_Wide_Type (Typ) then |
461 | Typ := Root_Type (Typ); | |
462 | end if; | |
463 | ||
03456e44 AC |
464 | if Is_Private_Type (Typ) and then Present (Full_View (Typ)) then |
465 | Typ := Full_View (Typ); | |
466 | end if; | |
4f91a255 | 467 | |
03456e44 AC |
468 | if Is_Concurrent_Type (Typ) |
469 | and then | |
470 | Present (Corresponding_Record_Type (Typ)) | |
4f91a255 | 471 | then |
03456e44 | 472 | Typ := Corresponding_Record_Type (Typ); |
4f91a255 AC |
473 | |
474 | -- The concurrent record's list of primitives should contain a | |
475 | -- wrapper for the entity of the call, retrieve it. | |
476 | ||
477 | declare | |
478 | Prim : Entity_Id; | |
479 | Prim_Elmt : Elmt_Id; | |
480 | Wrapper_Found : Boolean := False; | |
481 | ||
482 | begin | |
483 | Prim_Elmt := First_Elmt (Primitive_Operations (Typ)); | |
484 | while Present (Prim_Elmt) loop | |
485 | Prim := Node (Prim_Elmt); | |
486 | ||
487 | if Is_Primitive_Wrapper (Prim) | |
488 | and then Wrapped_Entity (Prim) = Subp_Entity | |
489 | then | |
490 | Wrapper_Found := True; | |
491 | exit; | |
492 | end if; | |
493 | ||
494 | Next_Elmt (Prim_Elmt); | |
495 | end loop; | |
496 | ||
497 | -- A primitive declared between two views should have a | |
498 | -- corresponding wrapper. | |
499 | ||
500 | pragma Assert (Wrapper_Found); | |
501 | ||
502 | -- Modify the call by setting the proper entity | |
503 | ||
504 | Set_Entity (Name (N), Prim); | |
505 | end; | |
506 | end if; | |
507 | end Check_Direct_Call; | |
508 | ||
996ae0b0 RK |
509 | ------------------------------- |
510 | -- Check_Dispatching_Context -- | |
511 | ------------------------------- | |
512 | ||
0d66b596 AC |
513 | procedure Check_Dispatching_Context (Call : Node_Id) is |
514 | Subp : constant Entity_Id := Entity (Name (Call)); | |
996ae0b0 | 515 | |
8926d369 | 516 | procedure Abstract_Context_Error; |
03459f40 | 517 | -- Error for abstract call dispatching on result is not dispatching |
8926d369 | 518 | |
03459f40 AC |
519 | ---------------------------- |
520 | -- Abstract_Context_Error -- | |
521 | ---------------------------- | |
8926d369 AC |
522 | |
523 | procedure Abstract_Context_Error is | |
524 | begin | |
525 | if Ekind (Subp) = E_Function then | |
526 | Error_Msg_N | |
527 | ("call to abstract function must be dispatching", N); | |
528 | ||
03459f40 AC |
529 | -- This error can occur for a procedure in the case of a call to |
530 | -- an abstract formal procedure with a statically tagged operand. | |
8926d369 AC |
531 | |
532 | else | |
533 | Error_Msg_N | |
87fd6836 | 534 | ("call to abstract procedure must be dispatching", N); |
8926d369 AC |
535 | end if; |
536 | end Abstract_Context_Error; | |
537 | ||
0d66b596 AC |
538 | -- Local variables |
539 | ||
87fd6836 AC |
540 | Scop : constant Entity_Id := Current_Scope_No_Loops; |
541 | Typ : constant Entity_Id := Etype (Subp); | |
542 | Par : Node_Id; | |
0d66b596 | 543 | |
03459f40 AC |
544 | -- Start of processing for Check_Dispatching_Context |
545 | ||
996ae0b0 | 546 | begin |
5f8d3dd5 AC |
547 | -- If the called subprogram is a private overriding, replace it |
548 | -- with its alias, which has the correct body. Verify that the | |
549 | -- two subprograms have the same controlling type (this is not the | |
550 | -- case for an inherited subprogram that has become abstract). | |
551 | ||
dee4682a | 552 | if Is_Abstract_Subprogram (Subp) |
0d66b596 | 553 | and then No (Controlling_Argument (Call)) |
996ae0b0 | 554 | then |
82c80734 | 555 | if Present (Alias (Subp)) |
dee4682a | 556 | and then not Is_Abstract_Subprogram (Alias (Subp)) |
82c80734 | 557 | and then No (DTC_Entity (Subp)) |
5f8d3dd5 | 558 | and then Find_Dispatching_Type (Subp) = |
245fee17 | 559 | Find_Dispatching_Type (Alias (Subp)) |
07fc65c4 | 560 | then |
550f4135 AC |
561 | -- Private overriding of inherited abstract operation, call is |
562 | -- legal. | |
996ae0b0 | 563 | |
82c80734 | 564 | Set_Entity (Name (N), Alias (Subp)); |
07fc65c4 | 565 | return; |
996ae0b0 | 566 | |
88ff8916 AC |
567 | -- An obscure special case: a null procedure may have a class- |
568 | -- wide pre/postcondition that includes a call to an abstract | |
569 | -- subp. Calls within the expression may not have been rewritten | |
570 | -- as dispatching calls yet, because the null body appears in | |
571 | -- the current declarative part. The expression will be properly | |
572 | -- rewritten/reanalyzed when the postcondition procedure is built. | |
573 | ||
ebb6b0bd AC |
574 | -- Similarly, if this is a pre/postcondition for an abstract |
575 | -- subprogram, it may call another abstract function which is | |
576 | -- a primitive of an abstract type. The call is non-dispatching | |
577 | -- but will be legal in overridings of the operation. | |
578 | ||
321c24f7 | 579 | elsif (Is_Subprogram (Scop) |
8f34c90b | 580 | or else Chars (Scop) = Name_Postcondition) |
87fd6836 AC |
581 | and then |
582 | (Is_Abstract_Subprogram (Scop) | |
583 | or else | |
584 | (Nkind (Parent (Scop)) = N_Procedure_Specification | |
585 | and then Null_Present (Parent (Scop)))) | |
88ff8916 AC |
586 | then |
587 | null; | |
588 | ||
b6dd03dd | 589 | elsif Ekind (Current_Scope) = E_Function |
87fd6836 AC |
590 | and then Nkind (Unit_Declaration_Node (Scop)) = |
591 | N_Generic_Subprogram_Declaration | |
b6dd03dd ES |
592 | then |
593 | null; | |
594 | ||
07fc65c4 | 595 | else |
8926d369 AC |
596 | -- We need to determine whether the context of the call |
597 | -- provides a tag to make the call dispatching. This requires | |
598 | -- the call to be the actual in an enclosing call, and that | |
64ac53f4 | 599 | -- actual must be controlling. If the call is an operand of |
8926d369 AC |
600 | -- equality, the other operand must not ve abstract. |
601 | ||
602 | if not Is_Tagged_Type (Typ) | |
603 | and then not | |
0d66b596 AC |
604 | (Ekind (Typ) = E_Anonymous_Access_Type |
605 | and then Is_Tagged_Type (Designated_Type (Typ))) | |
8926d369 AC |
606 | then |
607 | Abstract_Context_Error; | |
608 | return; | |
609 | end if; | |
610 | ||
0d66b596 | 611 | Par := Parent (Call); |
03459f40 | 612 | |
8926d369 AC |
613 | if Nkind (Par) = N_Parameter_Association then |
614 | Par := Parent (Par); | |
615 | end if; | |
616 | ||
0d66b596 AC |
617 | if Nkind (Par) = N_Qualified_Expression |
618 | or else Nkind (Par) = N_Unchecked_Type_Conversion | |
619 | then | |
620 | Par := Parent (Par); | |
621 | end if; | |
8926d369 | 622 | |
0d66b596 AC |
623 | if Nkind_In (Par, N_Function_Call, N_Procedure_Call_Statement) |
624 | and then Is_Entity_Name (Name (Par)) | |
625 | then | |
626 | declare | |
627 | Enc_Subp : constant Entity_Id := Entity (Name (Par)); | |
628 | A : Node_Id; | |
629 | F : Entity_Id; | |
630 | Control : Entity_Id; | |
631 | Ret_Type : Entity_Id; | |
632 | ||
633 | begin | |
634 | -- Find controlling formal that can provide tag for the | |
635 | -- tag-indeterminate actual. The corresponding actual | |
636 | -- must be the corresponding class-wide type. | |
637 | ||
638 | F := First_Formal (Enc_Subp); | |
639 | A := First_Actual (Par); | |
640 | ||
641 | -- Find controlling type of call. Dereference if function | |
642 | -- returns an access type. | |
643 | ||
644 | Ret_Type := Etype (Call); | |
645 | if Is_Access_Type (Etype (Call)) then | |
646 | Ret_Type := Designated_Type (Ret_Type); | |
647 | end if; | |
ec6cfc5d | 648 | |
0d66b596 AC |
649 | while Present (F) loop |
650 | Control := Etype (A); | |
8926d369 | 651 | |
0d66b596 AC |
652 | if Is_Access_Type (Control) then |
653 | Control := Designated_Type (Control); | |
654 | end if; | |
07fc65c4 | 655 | |
0d66b596 AC |
656 | if Is_Controlling_Formal (F) |
657 | and then not (Call = A or else Parent (Call) = A) | |
658 | and then Control = Class_Wide_Type (Ret_Type) | |
659 | then | |
660 | return; | |
661 | end if; | |
82c80734 | 662 | |
0d66b596 AC |
663 | Next_Formal (F); |
664 | Next_Actual (A); | |
665 | end loop; | |
82c80734 | 666 | |
0d66b596 AC |
667 | if Nkind (Par) = N_Function_Call |
668 | and then Is_Tag_Indeterminate (Par) | |
8926d369 | 669 | then |
0d66b596 | 670 | -- The parent may be an actual of an enclosing call |
8926d369 | 671 | |
0d66b596 AC |
672 | Check_Dispatching_Context (Par); |
673 | return; | |
82c80734 | 674 | |
0d66b596 AC |
675 | else |
676 | Error_Msg_N | |
677 | ("call to abstract function must be dispatching", | |
678 | Call); | |
679 | return; | |
680 | end if; | |
681 | end; | |
8926d369 | 682 | |
0d66b596 AC |
683 | -- For equality operators, one of the operands must be |
684 | -- statically or dynamically tagged. | |
8926d369 | 685 | |
0d66b596 AC |
686 | elsif Nkind_In (Par, N_Op_Eq, N_Op_Ne) then |
687 | if N = Right_Opnd (Par) | |
688 | and then Is_Tag_Indeterminate (Left_Opnd (Par)) | |
8926d369 | 689 | then |
0d66b596 | 690 | Abstract_Context_Error; |
8926d369 | 691 | |
0d66b596 AC |
692 | elsif N = Left_Opnd (Par) |
693 | and then Is_Tag_Indeterminate (Right_Opnd (Par)) | |
694 | then | |
8926d369 | 695 | Abstract_Context_Error; |
07fc65c4 | 696 | end if; |
0d66b596 AC |
697 | |
698 | return; | |
699 | ||
700 | -- The left-hand side of an assignment provides the tag | |
701 | ||
702 | elsif Nkind (Par) = N_Assignment_Statement then | |
703 | return; | |
704 | ||
705 | else | |
706 | Abstract_Context_Error; | |
707 | end if; | |
07fc65c4 | 708 | end if; |
996ae0b0 RK |
709 | end if; |
710 | end Check_Dispatching_Context; | |
711 | ||
712 | -- Start of processing for Check_Dispatching_Call | |
713 | ||
714 | begin | |
715 | -- Find a controlling argument, if any | |
716 | ||
717 | if Present (Parameter_Associations (N)) then | |
82c80734 | 718 | Subp_Entity := Entity (Name (N)); |
82c80734 | 719 | |
0e41a941 AC |
720 | Actual := First_Actual (N); |
721 | Formal := First_Formal (Subp_Entity); | |
996ae0b0 RK |
722 | while Present (Actual) loop |
723 | Control := Find_Controlling_Arg (Actual); | |
724 | exit when Present (Control); | |
82c80734 RD |
725 | |
726 | -- Check for the case where the actual is a tag-indeterminate call | |
727 | -- whose result type is different than the tagged type associated | |
728 | -- with the containing call, but is an ancestor of the type. | |
729 | ||
730 | if Is_Controlling_Formal (Formal) | |
731 | and then Is_Tag_Indeterminate (Actual) | |
732 | and then Base_Type (Etype (Actual)) /= Base_Type (Etype (Formal)) | |
733 | and then Is_Ancestor (Etype (Actual), Etype (Formal)) | |
734 | then | |
735 | Indeterm_Ancestor_Call := True; | |
736 | Indeterm_Ctrl_Type := Etype (Formal); | |
d215a13c ES |
737 | |
738 | -- If the formal is controlling but the actual is not, the type | |
739 | -- of the actual is statically known, and may be used as the | |
550f4135 | 740 | -- controlling tag for some other tag-indeterminate actual. |
d215a13c ES |
741 | |
742 | elsif Is_Controlling_Formal (Formal) | |
743 | and then Is_Entity_Name (Actual) | |
744 | and then Is_Tagged_Type (Etype (Actual)) | |
745 | then | |
746 | Static_Tag := Actual; | |
82c80734 RD |
747 | end if; |
748 | ||
996ae0b0 | 749 | Next_Actual (Actual); |
82c80734 | 750 | Next_Formal (Formal); |
996ae0b0 RK |
751 | end loop; |
752 | ||
550f4135 AC |
753 | -- If the call doesn't have a controlling actual but does have an |
754 | -- indeterminate actual that requires dispatching treatment, then an | |
03459f40 | 755 | -- object is needed that will serve as the controlling argument for |
ec6cfc5d AC |
756 | -- a dispatching call on the indeterminate actual. This can occur |
757 | -- in the unusual situation of a default actual given by a tag- | |
758 | -- indeterminate call and where the type of the call is an ancestor | |
759 | -- of the type associated with a containing call to an inherited | |
760 | -- operation (see AI-239). | |
550f4135 | 761 | |
03459f40 AC |
762 | -- Rather than create an object of the tagged type, which would |
763 | -- be problematic for various reasons (default initialization, | |
764 | -- discriminants), the tag of the containing call's associated | |
765 | -- tagged type is directly used to control the dispatching. | |
82c80734 | 766 | |
3bcd6930 | 767 | if No (Control) |
82c80734 | 768 | and then Indeterm_Ancestor_Call |
d215a13c | 769 | and then No (Static_Tag) |
82c80734 RD |
770 | then |
771 | Control := | |
772 | Make_Attribute_Reference (Loc, | |
773 | Prefix => New_Occurrence_Of (Indeterm_Ctrl_Type, Loc), | |
774 | Attribute_Name => Name_Tag); | |
d215a13c | 775 | |
82c80734 RD |
776 | Analyze (Control); |
777 | end if; | |
778 | ||
996ae0b0 RK |
779 | if Present (Control) then |
780 | ||
781 | -- Verify that no controlling arguments are statically tagged | |
782 | ||
783 | if Debug_Flag_E then | |
784 | Write_Str ("Found Dispatching call"); | |
785 | Write_Int (Int (N)); | |
786 | Write_Eol; | |
787 | end if; | |
788 | ||
789 | Actual := First_Actual (N); | |
996ae0b0 RK |
790 | while Present (Actual) loop |
791 | if Actual /= Control then | |
792 | ||
793 | if not Is_Controlling_Actual (Actual) then | |
82c80734 | 794 | null; -- Can be anything |
996ae0b0 | 795 | |
fbf5a39b | 796 | elsif Is_Dynamically_Tagged (Actual) then |
82c80734 | 797 | null; -- Valid parameter |
996ae0b0 RK |
798 | |
799 | elsif Is_Tag_Indeterminate (Actual) then | |
800 | ||
550f4135 AC |
801 | -- The tag is inherited from the enclosing call (the node |
802 | -- we are currently analyzing). Explicitly expand the | |
803 | -- actual, since the previous call to Expand (from | |
03459f40 AC |
804 | -- Resolve_Call) had no way of knowing about the |
805 | -- required dispatching. | |
996ae0b0 RK |
806 | |
807 | Propagate_Tag (Control, Actual); | |
808 | ||
809 | else | |
810 | Error_Msg_N | |
811 | ("controlling argument is not dynamically tagged", | |
812 | Actual); | |
813 | return; | |
814 | end if; | |
815 | end if; | |
816 | ||
817 | Next_Actual (Actual); | |
818 | end loop; | |
819 | ||
820 | -- Mark call as a dispatching call | |
821 | ||
822 | Set_Controlling_Argument (N, Control); | |
dee4682a | 823 | Check_Restriction (No_Dispatching_Calls, N); |
996ae0b0 | 824 | |
4f91a255 AC |
825 | -- The dispatching call may need to be converted into a direct |
826 | -- call in certain cases. | |
827 | ||
828 | Check_Direct_Call; | |
829 | ||
20e8cdd7 GD |
830 | -- If there is a statically tagged actual and a tag-indeterminate |
831 | -- call to a function of the ancestor (such as that provided by a | |
832 | -- default), then treat this as a dispatching call and propagate | |
833 | -- the tag to the tag-indeterminate call(s). | |
d215a13c | 834 | |
20e8cdd7 | 835 | elsif Present (Static_Tag) and then Indeterm_Ancestor_Call then |
d215a13c ES |
836 | Control := |
837 | Make_Attribute_Reference (Loc, | |
838 | Prefix => | |
839 | New_Occurrence_Of (Etype (Static_Tag), Loc), | |
840 | Attribute_Name => Name_Tag); | |
841 | ||
842 | Analyze (Control); | |
843 | ||
844 | Actual := First_Actual (N); | |
845 | Formal := First_Formal (Subp_Entity); | |
846 | while Present (Actual) loop | |
847 | if Is_Tag_Indeterminate (Actual) | |
848 | and then Is_Controlling_Formal (Formal) | |
849 | then | |
850 | Propagate_Tag (Control, Actual); | |
851 | end if; | |
852 | ||
853 | Next_Actual (Actual); | |
854 | Next_Formal (Formal); | |
855 | end loop; | |
856 | ||
0d66b596 AC |
857 | Check_Dispatching_Context (N); |
858 | ||
859 | elsif Nkind (N) /= N_Function_Call then | |
d215a13c | 860 | |
82c80734 | 861 | -- The call is not dispatching, so check that there aren't any |
0d66b596 | 862 | -- tag-indeterminate abstract calls left among its actuals. |
996ae0b0 RK |
863 | |
864 | Actual := First_Actual (N); | |
996ae0b0 RK |
865 | while Present (Actual) loop |
866 | if Is_Tag_Indeterminate (Actual) then | |
867 | ||
868 | -- Function call case | |
869 | ||
870 | if Nkind (Original_Node (Actual)) = N_Function_Call then | |
871 | Func := Entity (Name (Original_Node (Actual))); | |
872 | ||
3bcd6930 JM |
873 | -- If the actual is an attribute then it can't be abstract |
874 | -- (the only current case of a tag-indeterminate attribute | |
875 | -- is the stream Input attribute). | |
876 | ||
ccd6f414 | 877 | elsif Nkind (Original_Node (Actual)) = N_Attribute_Reference |
3bcd6930 JM |
878 | then |
879 | Func := Empty; | |
880 | ||
0d66b596 | 881 | -- Ditto if it is an explicit dereference |
167b47d9 | 882 | |
ccd6f414 | 883 | elsif Nkind (Original_Node (Actual)) = N_Explicit_Dereference |
167b47d9 AC |
884 | then |
885 | Func := Empty; | |
886 | ||
996ae0b0 | 887 | -- Only other possibility is a qualified expression whose |
8909e1ed | 888 | -- constituent expression is itself a call. |
996ae0b0 RK |
889 | |
890 | else | |
891 | Func := | |
ccd6f414 | 892 | Entity (Name (Original_Node |
0d66b596 | 893 | (Expression (Original_Node (Actual))))); |
996ae0b0 RK |
894 | end if; |
895 | ||
dee4682a | 896 | if Present (Func) and then Is_Abstract_Subprogram (Func) then |
ed2233dc | 897 | Error_Msg_N |
0d66b596 AC |
898 | ("call to abstract function must be dispatching", |
899 | Actual); | |
996ae0b0 RK |
900 | end if; |
901 | end if; | |
902 | ||
903 | Next_Actual (Actual); | |
904 | end loop; | |
905 | ||
0d66b596 AC |
906 | Check_Dispatching_Context (N); |
907 | return; | |
908 | ||
909 | elsif Nkind (Parent (N)) in N_Subexpr then | |
910 | Check_Dispatching_Context (N); | |
911 | ||
912 | elsif Nkind (Parent (N)) = N_Assignment_Statement | |
913 | and then Is_Class_Wide_Type (Etype (Name (Parent (N)))) | |
914 | then | |
915 | return; | |
916 | ||
917 | elsif Is_Abstract_Subprogram (Subp_Entity) then | |
918 | Check_Dispatching_Context (N); | |
919 | return; | |
996ae0b0 RK |
920 | end if; |
921 | ||
922 | else | |
923 | -- If dispatching on result, the enclosing call, if any, will | |
924 | -- determine the controlling argument. Otherwise this is the | |
925 | -- primitive operation of the root type. | |
926 | ||
0d66b596 | 927 | Check_Dispatching_Context (N); |
996ae0b0 RK |
928 | end if; |
929 | end Check_Dispatching_Call; | |
930 | ||
931 | --------------------------------- | |
932 | -- Check_Dispatching_Operation -- | |
933 | --------------------------------- | |
934 | ||
935 | procedure Check_Dispatching_Operation (Subp, Old_Subp : Entity_Id) is | |
48c8c473 AC |
936 | procedure Warn_On_Late_Primitive_After_Private_Extension |
937 | (Typ : Entity_Id; | |
938 | Prim : Entity_Id); | |
939 | -- Prim is a dispatching primitive of the tagged type Typ. Warn on Prim | |
940 | -- if it is a public primitive defined after some private extension of | |
941 | -- the tagged type. | |
942 | ||
943 | ---------------------------------------------------- | |
944 | -- Warn_On_Late_Primitive_After_Private_Extension -- | |
945 | ---------------------------------------------------- | |
946 | ||
947 | procedure Warn_On_Late_Primitive_After_Private_Extension | |
948 | (Typ : Entity_Id; | |
949 | Prim : Entity_Id) | |
950 | is | |
951 | E : Entity_Id; | |
952 | ||
953 | begin | |
954 | if Warn_On_Late_Primitives | |
955 | and then Comes_From_Source (Prim) | |
956 | and then Has_Private_Extension (Typ) | |
957 | and then Is_Package_Or_Generic_Package (Current_Scope) | |
958 | and then not In_Private_Part (Current_Scope) | |
959 | then | |
960 | E := Next_Entity (Typ); | |
961 | ||
962 | while E /= Prim loop | |
963 | if Ekind (E) = E_Record_Type_With_Private | |
964 | and then Etype (E) = Typ | |
965 | then | |
966 | Error_Msg_Name_1 := Chars (Typ); | |
967 | Error_Msg_Name_2 := Chars (E); | |
968 | Error_Msg_Sloc := Sloc (E); | |
969 | Error_Msg_N | |
ec40b86c HK |
970 | ("?j?primitive of type % defined after private extension " |
971 | & "% #?", Prim); | |
48c8c473 AC |
972 | Error_Msg_Name_1 := Chars (Prim); |
973 | Error_Msg_Name_2 := Chars (E); | |
974 | Error_Msg_N | |
975 | ("\spec of % should appear before declaration of type %!", | |
976 | Prim); | |
977 | exit; | |
978 | end if; | |
979 | ||
980 | Next_Entity (E); | |
981 | end loop; | |
982 | end if; | |
983 | end Warn_On_Late_Primitive_After_Private_Extension; | |
984 | ||
985 | -- Local variables | |
986 | ||
ea034236 | 987 | Body_Is_Last_Primitive : Boolean := False; |
54740d7d | 988 | Has_Dispatching_Parent : Boolean := False; |
ea034236 | 989 | Ovr_Subp : Entity_Id := Empty; |
54740d7d | 990 | Tagged_Type : Entity_Id; |
996ae0b0 | 991 | |
ec40b86c HK |
992 | -- Start of processing for Check_Dispatching_Operation |
993 | ||
996ae0b0 | 994 | begin |
54740d7d AC |
995 | if not Ekind_In (Subp, E_Function, E_Procedure) then |
996 | return; | |
997 | ||
998 | -- The Default_Initial_Condition procedure is not a primitive subprogram | |
999 | -- even if it relates to a tagged type. This routine is not meant to be | |
1000 | -- inherited or overridden. | |
1001 | ||
1002 | elsif Is_DIC_Procedure (Subp) then | |
1003 | return; | |
1004 | ||
1005 | -- The "partial" and "full" type invariant procedures are not primitive | |
1006 | -- subprograms even if they relate to a tagged type. These routines are | |
1007 | -- not meant to be inherited or overridden. | |
1008 | ||
1009 | elsif Is_Invariant_Procedure (Subp) | |
1010 | or else Is_Partial_Invariant_Procedure (Subp) | |
1011 | then | |
996ae0b0 RK |
1012 | return; |
1013 | end if; | |
1014 | ||
1015 | Set_Is_Dispatching_Operation (Subp, False); | |
07fc65c4 | 1016 | Tagged_Type := Find_Dispatching_Type (Subp); |
996ae0b0 | 1017 | |
bb10b891 | 1018 | -- Ada 2005 (AI-345): Use the corresponding record (if available). |
f0b741b6 | 1019 | -- Required because primitives of concurrent types are attached |
bb10b891 | 1020 | -- to the corresponding record (not to the concurrent type). |
758c442c | 1021 | |
0791fbe9 | 1022 | if Ada_Version >= Ada_2005 |
758c442c GD |
1023 | and then Present (Tagged_Type) |
1024 | and then Is_Concurrent_Type (Tagged_Type) | |
bb10b891 | 1025 | and then Present (Corresponding_Record_Type (Tagged_Type)) |
758c442c GD |
1026 | then |
1027 | Tagged_Type := Corresponding_Record_Type (Tagged_Type); | |
1028 | end if; | |
1029 | ||
ce2b6ba5 JM |
1030 | -- (AI-345): The task body procedure is not a primitive of the tagged |
1031 | -- type | |
1032 | ||
1033 | if Present (Tagged_Type) | |
1034 | and then Is_Concurrent_Record_Type (Tagged_Type) | |
1035 | and then Present (Corresponding_Concurrent_Type (Tagged_Type)) | |
1036 | and then Is_Task_Type (Corresponding_Concurrent_Type (Tagged_Type)) | |
1037 | and then Subp = Get_Task_Body_Procedure | |
1038 | (Corresponding_Concurrent_Type (Tagged_Type)) | |
1039 | then | |
1040 | return; | |
1041 | end if; | |
1042 | ||
996ae0b0 RK |
1043 | -- If Subp is derived from a dispatching operation then it should |
1044 | -- always be treated as dispatching. In this case various checks | |
1045 | -- below will be bypassed. Makes sure that late declarations for | |
1046 | -- inherited private subprograms are treated as dispatching, even | |
1047 | -- if the associated tagged type is already frozen. | |
1048 | ||
fbf5a39b | 1049 | Has_Dispatching_Parent := |
87fd6836 AC |
1050 | Present (Alias (Subp)) |
1051 | and then Is_Dispatching_Operation (Alias (Subp)); | |
996ae0b0 | 1052 | |
07fc65c4 | 1053 | if No (Tagged_Type) then |
67f3c450 HK |
1054 | |
1055 | -- Ada 2005 (AI-251): Check that Subp is not a primitive associated | |
1056 | -- with an abstract interface type unless the interface acts as a | |
1057 | -- parent type in a derivation. If the interface type is a formal | |
1058 | -- type then the operation is not primitive and therefore legal. | |
1059 | ||
1060 | declare | |
1061 | E : Entity_Id; | |
1062 | Typ : Entity_Id; | |
1063 | ||
1064 | begin | |
1065 | E := First_Entity (Subp); | |
1066 | while Present (E) loop | |
76a69663 | 1067 | |
01957849 | 1068 | -- For an access parameter, check designated type |
76a69663 ES |
1069 | |
1070 | if Ekind (Etype (E)) = E_Anonymous_Access_Type then | |
67f3c450 HK |
1071 | Typ := Designated_Type (Etype (E)); |
1072 | else | |
1073 | Typ := Etype (E); | |
1074 | end if; | |
1075 | ||
f9c0d38c | 1076 | if Comes_From_Source (Subp) |
67f3c450 | 1077 | and then Is_Interface (Typ) |
f9c0d38c | 1078 | and then not Is_Class_Wide_Type (Typ) |
67f3c450 HK |
1079 | and then not Is_Derived_Type (Typ) |
1080 | and then not Is_Generic_Type (Typ) | |
8909e1ed | 1081 | and then not In_Instance |
67f3c450 | 1082 | then |
324ac540 | 1083 | Error_Msg_N ("??declaration of& is too late!", Subp); |
ed2233dc | 1084 | Error_Msg_NE -- CODEFIX?? |
ec40b86c HK |
1085 | ("\??spec should appear immediately after declaration of " |
1086 | & "& !", Subp, Typ); | |
67f3c450 HK |
1087 | exit; |
1088 | end if; | |
1089 | ||
1090 | Next_Entity (E); | |
1091 | end loop; | |
1092 | ||
1093 | -- In case of functions check also the result type | |
1094 | ||
1095 | if Ekind (Subp) = E_Function then | |
1096 | if Is_Access_Type (Etype (Subp)) then | |
1097 | Typ := Designated_Type (Etype (Subp)); | |
1098 | else | |
1099 | Typ := Etype (Subp); | |
1100 | end if; | |
1101 | ||
996c8821 RD |
1102 | -- The following should be better commented, especially since |
1103 | -- we just added several new conditions here ??? | |
1104 | ||
d15f9422 | 1105 | if Comes_From_Source (Subp) |
67f3c450 | 1106 | and then Is_Interface (Typ) |
d15f9422 | 1107 | and then not Is_Class_Wide_Type (Typ) |
67f3c450 | 1108 | and then not Is_Derived_Type (Typ) |
d15f9422 AC |
1109 | and then not Is_Generic_Type (Typ) |
1110 | and then not In_Instance | |
67f3c450 | 1111 | then |
324ac540 | 1112 | Error_Msg_N ("??declaration of& is too late!", Subp); |
67f3c450 | 1113 | Error_Msg_NE |
ec40b86c HK |
1114 | ("\??spec should appear immediately after declaration of " |
1115 | & "& !", Subp, Typ); | |
67f3c450 HK |
1116 | end if; |
1117 | end if; | |
1118 | end; | |
1119 | ||
996ae0b0 RK |
1120 | return; |
1121 | ||
1122 | -- The subprograms build internally after the freezing point (such as | |
26a43556 AC |
1123 | -- init procs, interface thunks, type support subprograms, and Offset |
1124 | -- to top functions for accessing interface components in variable | |
1125 | -- size tagged types) are not primitives. | |
996ae0b0 | 1126 | |
07fc65c4 | 1127 | elsif Is_Frozen (Tagged_Type) |
996ae0b0 RK |
1128 | and then not Comes_From_Source (Subp) |
1129 | and then not Has_Dispatching_Parent | |
1130 | then | |
74853971 | 1131 | -- Complete decoration of internally built subprograms that override |
26a43556 AC |
1132 | -- a dispatching primitive. These entities correspond with the |
1133 | -- following cases: | |
1134 | ||
1135 | -- 1. Ada 2005 (AI-391): Wrapper functions built by the expander | |
1136 | -- to override functions of nonabstract null extensions. These | |
1137 | -- primitives were added to the list of primitives of the tagged | |
1138 | -- type by Make_Controlling_Function_Wrappers. However, attribute | |
1139 | -- Is_Dispatching_Operation must be set to true. | |
1140 | ||
0052da20 JM |
1141 | -- 2. Ada 2005 (AI-251): Wrapper procedures of null interface |
1142 | -- primitives. | |
1143 | ||
1144 | -- 3. Subprograms associated with stream attributes (built by | |
26a43556 AC |
1145 | -- New_Stream_Subprogram) |
1146 | ||
31fde973 | 1147 | -- 4. Wrappers built for inherited operations with inherited class- |
a187206c AC |
1148 | -- wide conditions, where the conditions include calls to other |
1149 | -- overridden primitives. The wrappers include checks on these | |
1150 | -- modified conditions. (AI12-113). | |
1151 | ||
31fde973 | 1152 | -- 5. Declarations built for subprograms without separate specs that |
bab15911 YM |
1153 | -- are eligible for inlining in GNATprove (inside |
1154 | -- Sem_Ch6.Analyze_Subprogram_Body_Helper). | |
1155 | ||
26a43556 | 1156 | if Present (Old_Subp) |
038140ed | 1157 | and then Present (Overridden_Operation (Subp)) |
26a43556 AC |
1158 | and then Is_Dispatching_Operation (Old_Subp) |
1159 | then | |
1160 | pragma Assert | |
df3e68b1 | 1161 | ((Ekind (Subp) = E_Function |
2c1b72d7 AC |
1162 | and then Is_Dispatching_Operation (Old_Subp) |
1163 | and then Is_Null_Extension (Base_Type (Etype (Subp)))) | |
a187206c | 1164 | |
df3e68b1 HK |
1165 | or else |
1166 | (Ekind (Subp) = E_Procedure | |
2c1b72d7 AC |
1167 | and then Is_Dispatching_Operation (Old_Subp) |
1168 | and then Present (Alias (Old_Subp)) | |
1169 | and then Is_Null_Interface_Primitive | |
0052da20 | 1170 | (Ultimate_Alias (Old_Subp))) |
a187206c | 1171 | |
df3e68b1 | 1172 | or else Get_TSS_Name (Subp) = TSS_Stream_Read |
a187206c AC |
1173 | or else Get_TSS_Name (Subp) = TSS_Stream_Write |
1174 | ||
bab15911 YM |
1175 | or else Present (Contract (Overridden_Operation (Subp))) |
1176 | ||
1177 | or else GNATprove_Mode); | |
26a43556 | 1178 | |
0052da20 JM |
1179 | Check_Controlling_Formals (Tagged_Type, Subp); |
1180 | Override_Dispatching_Operation (Tagged_Type, Old_Subp, Subp); | |
26a43556 AC |
1181 | Set_Is_Dispatching_Operation (Subp); |
1182 | end if; | |
1183 | ||
996ae0b0 RK |
1184 | return; |
1185 | ||
1186 | -- The operation may be a child unit, whose scope is the defining | |
1187 | -- package, but which is not a primitive operation of the type. | |
1188 | ||
1189 | elsif Is_Child_Unit (Subp) then | |
1190 | return; | |
1191 | ||
1192 | -- If the subprogram is not defined in a package spec, the only case | |
1193 | -- where it can be a dispatching op is when it overrides an operation | |
1194 | -- before the freezing point of the type. | |
1195 | ||
5dcc05e6 JM |
1196 | elsif ((not Is_Package_Or_Generic_Package (Scope (Subp))) |
1197 | or else In_Package_Body (Scope (Subp))) | |
996ae0b0 RK |
1198 | and then not Has_Dispatching_Parent |
1199 | then | |
1200 | if not Comes_From_Source (Subp) | |
07fc65c4 | 1201 | or else (Present (Old_Subp) and then not Is_Frozen (Tagged_Type)) |
996ae0b0 RK |
1202 | then |
1203 | null; | |
1204 | ||
1205 | -- If the type is already frozen, the overriding is not allowed | |
d7f94401 AC |
1206 | -- except when Old_Subp is not a dispatching operation (which can |
1207 | -- occur when Old_Subp was inherited by an untagged type). However, | |
0e41a941 | 1208 | -- a body with no previous spec freezes the type *after* its |
d7f94401 AC |
1209 | -- declaration, and therefore is a legal overriding (unless the type |
1210 | -- has already been frozen). Only the first such body is legal. | |
996ae0b0 RK |
1211 | |
1212 | elsif Present (Old_Subp) | |
1213 | and then Is_Dispatching_Operation (Old_Subp) | |
1214 | then | |
758c442c GD |
1215 | if Comes_From_Source (Subp) |
1216 | and then | |
1217 | (Nkind (Unit_Declaration_Node (Subp)) = N_Subprogram_Body | |
1218 | or else Nkind (Unit_Declaration_Node (Subp)) in N_Body_Stub) | |
996ae0b0 RK |
1219 | then |
1220 | declare | |
1221 | Subp_Body : constant Node_Id := Unit_Declaration_Node (Subp); | |
0e41a941 | 1222 | Decl_Item : Node_Id; |
996ae0b0 RK |
1223 | |
1224 | begin | |
03459f40 AC |
1225 | -- ??? The checks here for whether the type has been frozen |
1226 | -- prior to the new body are not complete. It's not simple | |
1227 | -- to check frozenness at this point since the body has | |
1228 | -- already caused the type to be prematurely frozen in | |
1229 | -- Analyze_Declarations, but we're forced to recheck this | |
1230 | -- here because of the odd rule interpretation that allows | |
1231 | -- the overriding if the type wasn't frozen prior to the | |
1232 | -- body. The freezing action should probably be delayed | |
1233 | -- until after the spec is seen, but that's a tricky | |
1234 | -- change to the delicate freezing code. | |
996ae0b0 | 1235 | |
f559e62f AC |
1236 | -- Look at each declaration following the type up until the |
1237 | -- new subprogram body. If any of the declarations is a body | |
1238 | -- then the type has been frozen already so the overriding | |
1239 | -- primitive is illegal. | |
996ae0b0 | 1240 | |
0e41a941 | 1241 | Decl_Item := Next (Parent (Tagged_Type)); |
996ae0b0 RK |
1242 | while Present (Decl_Item) |
1243 | and then (Decl_Item /= Subp_Body) | |
1244 | loop | |
1245 | if Comes_From_Source (Decl_Item) | |
1246 | and then (Nkind (Decl_Item) in N_Proper_Body | |
1247 | or else Nkind (Decl_Item) in N_Body_Stub) | |
1248 | then | |
1249 | Error_Msg_N ("overriding of& is too late!", Subp); | |
1250 | Error_Msg_N | |
1251 | ("\spec should appear immediately after the type!", | |
1252 | Subp); | |
1253 | exit; | |
1254 | end if; | |
1255 | ||
1256 | Next (Decl_Item); | |
1257 | end loop; | |
1258 | ||
1259 | -- If the subprogram doesn't follow in the list of | |
f559e62f AC |
1260 | -- declarations including the type then the type has |
1261 | -- definitely been frozen already and the body is illegal. | |
996ae0b0 | 1262 | |
3bcd6930 | 1263 | if No (Decl_Item) then |
996ae0b0 RK |
1264 | Error_Msg_N ("overriding of& is too late!", Subp); |
1265 | Error_Msg_N | |
1266 | ("\spec should appear immediately after the type!", | |
1267 | Subp); | |
1268 | ||
1269 | elsif Is_Frozen (Subp) then | |
1270 | ||
fbf5a39b | 1271 | -- The subprogram body declares a primitive operation. |
03459f40 | 1272 | -- If the subprogram is already frozen, we must update |
996ae0b0 RK |
1273 | -- its dispatching information explicitly here. The |
1274 | -- information is taken from the overridden subprogram. | |
f7d5442e ES |
1275 | -- We must also generate a cross-reference entry because |
1276 | -- references to other primitives were already created | |
1277 | -- when type was frozen. | |
996ae0b0 RK |
1278 | |
1279 | Body_Is_Last_Primitive := True; | |
1280 | ||
1281 | if Present (DTC_Entity (Old_Subp)) then | |
1282 | Set_DTC_Entity (Subp, DTC_Entity (Old_Subp)); | |
024d33d8 | 1283 | Set_DT_Position_Value (Subp, DT_Position (Old_Subp)); |
3bcd6930 JM |
1284 | |
1285 | if not Restriction_Active (No_Dispatching_Calls) then | |
6e818918 JM |
1286 | if Building_Static_DT (Tagged_Type) then |
1287 | ||
1288 | -- If the static dispatch table has not been | |
1289 | -- built then there is nothing else to do now; | |
1290 | -- otherwise we notify that we cannot build the | |
1291 | -- static dispatch table. | |
1292 | ||
1293 | if Has_Dispatch_Table (Tagged_Type) then | |
1294 | Error_Msg_N | |
a90bd866 RD |
1295 | ("overriding of& is too late for building " |
1296 | & " static dispatch tables!", Subp); | |
6e818918 | 1297 | Error_Msg_N |
a90bd866 RD |
1298 | ("\spec should appear immediately after " |
1299 | & "the type!", Subp); | |
6e818918 JM |
1300 | end if; |
1301 | ||
f46faa08 AC |
1302 | -- No code required to register primitives in VM |
1303 | -- targets | |
1304 | ||
535a8637 | 1305 | elsif not Tagged_Type_Expansion then |
f46faa08 AC |
1306 | null; |
1307 | ||
6e818918 | 1308 | else |
991395ab AC |
1309 | Insert_Actions_After (Subp_Body, |
1310 | Register_Primitive (Sloc (Subp_Body), | |
1311 | Prim => Subp)); | |
6e818918 | 1312 | end if; |
f7d5442e | 1313 | |
4fc26524 | 1314 | -- Indicate that this is an overriding operation, |
308e6f3a | 1315 | -- and replace the overridden entry in the list of |
4fc26524 AC |
1316 | -- primitive operations, which is used for xref |
1317 | -- generation subsequently. | |
1318 | ||
1319 | Generate_Reference (Tagged_Type, Subp, 'P', False); | |
1320 | Override_Dispatching_Operation | |
1321 | (Tagged_Type, Old_Subp, Subp); | |
3bcd6930 | 1322 | end if; |
996ae0b0 RK |
1323 | end if; |
1324 | end if; | |
1325 | end; | |
1326 | ||
1327 | else | |
1328 | Error_Msg_N ("overriding of& is too late!", Subp); | |
1329 | Error_Msg_N | |
1330 | ("\subprogram spec should appear immediately after the type!", | |
1331 | Subp); | |
1332 | end if; | |
1333 | ||
8909e1ed | 1334 | -- If the type is not frozen yet and we are not in the overriding |
996ae0b0 | 1335 | -- case it looks suspiciously like an attempt to define a primitive |
f559e62f | 1336 | -- operation, which requires the declaration to be in a package spec |
21a5b575 | 1337 | -- (3.2.3(6)). Only report cases where the type and subprogram are |
9c870c90 AC |
1338 | -- in the same declaration list (by checking the enclosing parent |
1339 | -- declarations), to avoid spurious warnings on subprograms in | |
03459f40 AC |
1340 | -- instance bodies when the type is declared in the instance spec |
1341 | -- but hasn't been frozen by the instance body. | |
21a5b575 AC |
1342 | |
1343 | elsif not Is_Frozen (Tagged_Type) | |
9c870c90 | 1344 | and then In_Same_List (Parent (Tagged_Type), Parent (Parent (Subp))) |
21a5b575 | 1345 | then |
996ae0b0 | 1346 | Error_Msg_N |
324ac540 | 1347 | ("??not dispatching (must be defined in a package spec)", Subp); |
996ae0b0 RK |
1348 | return; |
1349 | ||
1350 | -- When the type is frozen, it is legitimate to define a new | |
1351 | -- non-primitive operation. | |
1352 | ||
1353 | else | |
1354 | return; | |
1355 | end if; | |
1356 | ||
1357 | -- Now, we are sure that the scope is a package spec. If the subprogram | |
8909e1ed | 1358 | -- is declared after the freezing point of the type that's an error |
996ae0b0 | 1359 | |
07fc65c4 | 1360 | elsif Is_Frozen (Tagged_Type) and then not Has_Dispatching_Parent then |
996ae0b0 RK |
1361 | Error_Msg_N ("this primitive operation is declared too late", Subp); |
1362 | Error_Msg_NE | |
324ac540 | 1363 | ("??no primitive operations for& after this line", |
07fc65c4 GB |
1364 | Freeze_Node (Tagged_Type), |
1365 | Tagged_Type); | |
996ae0b0 RK |
1366 | return; |
1367 | end if; | |
1368 | ||
07fc65c4 | 1369 | Check_Controlling_Formals (Tagged_Type, Subp); |
996ae0b0 | 1370 | |
ea034236 AC |
1371 | Ovr_Subp := Old_Subp; |
1372 | ||
1373 | -- [Ada 2012:AI-0125]: Search for inherited hidden primitive that may be | |
0812b84e AC |
1374 | -- overridden by Subp. This only applies to source subprograms, and |
1375 | -- their declaration must carry an explicit overriding indicator. | |
ea034236 AC |
1376 | |
1377 | if No (Ovr_Subp) | |
1378 | and then Ada_Version >= Ada_2012 | |
0812b84e AC |
1379 | and then Comes_From_Source (Subp) |
1380 | and then | |
1381 | Nkind (Unit_Declaration_Node (Subp)) = N_Subprogram_Declaration | |
ea034236 AC |
1382 | then |
1383 | Ovr_Subp := Find_Hidden_Overridden_Primitive (Subp); | |
0812b84e AC |
1384 | |
1385 | -- Verify that the proper overriding indicator has been supplied. | |
1386 | ||
1387 | if Present (Ovr_Subp) | |
1388 | and then | |
1389 | not Must_Override (Specification (Unit_Declaration_Node (Subp))) | |
1390 | then | |
1391 | Error_Msg_NE ("missing overriding indicator for&", Subp, Subp); | |
1392 | end if; | |
ea034236 AC |
1393 | end if; |
1394 | ||
996ae0b0 RK |
1395 | -- Now it should be a correct primitive operation, put it in the list |
1396 | ||
ea034236 | 1397 | if Present (Ovr_Subp) then |
ce2b6ba5 | 1398 | |
550f4135 AC |
1399 | -- If the type has interfaces we complete this check after we set |
1400 | -- attribute Is_Dispatching_Operation. | |
ce2b6ba5 | 1401 | |
ea034236 | 1402 | Check_Subtype_Conformant (Subp, Ovr_Subp); |
6e818918 | 1403 | |
7b4ebba5 AC |
1404 | -- A primitive operation with the name of a primitive controlled |
1405 | -- operation does not override a non-visible overriding controlled | |
1406 | -- operation, i.e. one declared in a private part when the full | |
1407 | -- view of a type is controlled. Conversely, it will override a | |
1408 | -- visible operation that may be declared in a partial view when | |
1409 | -- the full view is controlled. | |
1410 | ||
b69cd36a | 1411 | if Nam_In (Chars (Subp), Name_Initialize, Name_Adjust, Name_Finalize) |
5950a3ac AC |
1412 | and then Is_Controlled (Tagged_Type) |
1413 | and then not Is_Visibly_Controlled (Tagged_Type) | |
7b4ebba5 | 1414 | and then not Is_Inherited_Public_Operation (Ovr_Subp) |
5950a3ac | 1415 | then |
038140ed | 1416 | Set_Overridden_Operation (Subp, Empty); |
b8dfbe1e | 1417 | |
fd0d899b AC |
1418 | -- If the subprogram specification carries an overriding |
1419 | -- indicator, no need for the warning: it is either redundant, | |
1420 | -- or else an error will be reported. | |
1421 | ||
1422 | if Nkind (Parent (Subp)) = N_Procedure_Specification | |
1423 | and then | |
1424 | (Must_Override (Parent (Subp)) | |
1425 | or else Must_Not_Override (Parent (Subp))) | |
1426 | then | |
1427 | null; | |
b8dfbe1e AC |
1428 | |
1429 | -- Here we need the warning | |
1430 | ||
fd0d899b AC |
1431 | else |
1432 | Error_Msg_NE | |
324ac540 | 1433 | ("operation does not override inherited&??", Subp, Subp); |
fd0d899b | 1434 | end if; |
b8dfbe1e | 1435 | |
5950a3ac | 1436 | else |
ea034236 | 1437 | Override_Dispatching_Operation (Tagged_Type, Ovr_Subp, Subp); |
67f3c450 HK |
1438 | |
1439 | -- Ada 2005 (AI-251): In case of late overriding of a primitive | |
1440 | -- that covers abstract interface subprograms we must register it | |
1441 | -- in all the secondary dispatch tables associated with abstract | |
36b8f95f AC |
1442 | -- interfaces. We do this now only if not building static tables, |
1443 | -- nor when the expander is inactive (we avoid trying to register | |
1444 | -- primitives in semantics-only mode, since the type may not have | |
1445 | -- an associated dispatch table). Otherwise the patch code is | |
1446 | -- emitted after those tables are built, to prevent access before | |
1447 | -- elaboration in gigi. | |
1448 | ||
4460a9bc | 1449 | if Body_Is_Last_Primitive and then Expander_Active then |
67f3c450 HK |
1450 | declare |
1451 | Subp_Body : constant Node_Id := Unit_Declaration_Node (Subp); | |
1452 | Elmt : Elmt_Id; | |
1453 | Prim : Node_Id; | |
1454 | ||
1455 | begin | |
1456 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); | |
1457 | while Present (Elmt) loop | |
1458 | Prim := Node (Elmt); | |
1459 | ||
f46faa08 AC |
1460 | -- No code required to register primitives in VM targets |
1461 | ||
67f3c450 | 1462 | if Present (Alias (Prim)) |
ce2b6ba5 | 1463 | and then Present (Interface_Alias (Prim)) |
67f3c450 | 1464 | and then Alias (Prim) = Subp |
991395ab | 1465 | and then not Building_Static_DT (Tagged_Type) |
535a8637 | 1466 | and then Tagged_Type_Expansion |
67f3c450 | 1467 | then |
991395ab AC |
1468 | Insert_Actions_After (Subp_Body, |
1469 | Register_Primitive (Sloc (Subp_Body), Prim => Prim)); | |
67f3c450 HK |
1470 | end if; |
1471 | ||
1472 | Next_Elmt (Elmt); | |
1473 | end loop; | |
1474 | ||
8909e1ed | 1475 | -- Redisplay the contents of the updated dispatch table |
67f3c450 HK |
1476 | |
1477 | if Debug_Flag_ZZ then | |
1478 | Write_Str ("Late overriding: "); | |
1479 | Write_DT (Tagged_Type); | |
1480 | end if; | |
1481 | end; | |
1482 | end if; | |
5950a3ac | 1483 | end if; |
3bcd6930 | 1484 | |
bb10b891 AC |
1485 | -- If the tagged type is a concurrent type then we must be compiling |
1486 | -- with no code generation (we are either compiling a generic unit or | |
1487 | -- compiling under -gnatc mode) because we have previously tested that | |
1488 | -- no serious errors has been reported. In this case we do not add the | |
1489 | -- primitive to the list of primitives of Tagged_Type but we leave the | |
1490 | -- primitive decorated as a dispatching operation to be able to analyze | |
1491 | -- and report errors associated with the Object.Operation notation. | |
1492 | ||
1493 | elsif Is_Concurrent_Type (Tagged_Type) then | |
1494 | pragma Assert (not Expander_Active); | |
27fd9ad8 | 1495 | |
fed8bd87 RD |
1496 | -- Attach operation to list of primitives of the synchronized type |
1497 | -- itself, for ASIS use. | |
27fd9ad8 | 1498 | |
9057bd6a | 1499 | Add_Dispatching_Operation (Tagged_Type, Subp); |
bb10b891 | 1500 | |
3bcd6930 JM |
1501 | -- If no old subprogram, then we add this as a dispatching operation, |
1502 | -- but we avoid doing this if an error was posted, to prevent annoying | |
1503 | -- cascaded errors. | |
1504 | ||
1505 | elsif not Error_Posted (Subp) then | |
07fc65c4 | 1506 | Add_Dispatching_Operation (Tagged_Type, Subp); |
996ae0b0 RK |
1507 | end if; |
1508 | ||
1509 | Set_Is_Dispatching_Operation (Subp, True); | |
1510 | ||
ce2b6ba5 JM |
1511 | -- Ada 2005 (AI-251): If the type implements interfaces we must check |
1512 | -- subtype conformance against all the interfaces covered by this | |
1513 | -- primitive. | |
1514 | ||
ea034236 | 1515 | if Present (Ovr_Subp) |
ce2b6ba5 JM |
1516 | and then Has_Interfaces (Tagged_Type) |
1517 | then | |
1518 | declare | |
1519 | Ifaces_List : Elist_Id; | |
1520 | Iface_Elmt : Elmt_Id; | |
1521 | Iface_Prim_Elmt : Elmt_Id; | |
1522 | Iface_Prim : Entity_Id; | |
1523 | Ret_Typ : Entity_Id; | |
1524 | ||
1525 | begin | |
1526 | Collect_Interfaces (Tagged_Type, Ifaces_List); | |
1527 | ||
1528 | Iface_Elmt := First_Elmt (Ifaces_List); | |
1529 | while Present (Iface_Elmt) loop | |
1530 | if not Is_Ancestor (Node (Iface_Elmt), Tagged_Type) then | |
1531 | Iface_Prim_Elmt := | |
1532 | First_Elmt (Primitive_Operations (Node (Iface_Elmt))); | |
1533 | while Present (Iface_Prim_Elmt) loop | |
1534 | Iface_Prim := Node (Iface_Prim_Elmt); | |
1535 | ||
1536 | if Is_Interface_Conformant | |
1537 | (Tagged_Type, Iface_Prim, Subp) | |
1538 | then | |
1539 | -- Handle procedures, functions whose return type | |
1540 | -- matches, or functions not returning interfaces | |
1541 | ||
1542 | if Ekind (Subp) = E_Procedure | |
1543 | or else Etype (Iface_Prim) = Etype (Subp) | |
1544 | or else not Is_Interface (Etype (Iface_Prim)) | |
1545 | then | |
1546 | Check_Subtype_Conformant | |
1547 | (New_Id => Subp, | |
1548 | Old_Id => Iface_Prim, | |
1549 | Err_Loc => Subp, | |
1550 | Skip_Controlling_Formals => True); | |
1551 | ||
1552 | -- Handle functions returning interfaces | |
1553 | ||
1554 | elsif Implements_Interface | |
1555 | (Etype (Subp), Etype (Iface_Prim)) | |
1556 | then | |
1557 | -- Temporarily force both entities to return the | |
1558 | -- same type. Required because Subtype_Conformant | |
1559 | -- does not handle this case. | |
1560 | ||
1561 | Ret_Typ := Etype (Iface_Prim); | |
1562 | Set_Etype (Iface_Prim, Etype (Subp)); | |
1563 | ||
1564 | Check_Subtype_Conformant | |
1565 | (New_Id => Subp, | |
1566 | Old_Id => Iface_Prim, | |
1567 | Err_Loc => Subp, | |
1568 | Skip_Controlling_Formals => True); | |
1569 | ||
1570 | Set_Etype (Iface_Prim, Ret_Typ); | |
1571 | end if; | |
1572 | end if; | |
1573 | ||
1574 | Next_Elmt (Iface_Prim_Elmt); | |
1575 | end loop; | |
1576 | end if; | |
1577 | ||
1578 | Next_Elmt (Iface_Elmt); | |
1579 | end loop; | |
1580 | end; | |
1581 | end if; | |
1582 | ||
996ae0b0 | 1583 | if not Body_Is_Last_Primitive then |
024d33d8 | 1584 | Set_DT_Position_Value (Subp, No_Uint); |
996ae0b0 | 1585 | |
07fc65c4 | 1586 | elsif Has_Controlled_Component (Tagged_Type) |
b69cd36a AC |
1587 | and then Nam_In (Chars (Subp), Name_Initialize, |
1588 | Name_Adjust, | |
1589 | Name_Finalize, | |
1590 | Name_Finalize_Address) | |
07fc65c4 GB |
1591 | then |
1592 | declare | |
fbf5a39b | 1593 | F_Node : constant Node_Id := Freeze_Node (Tagged_Type); |
07fc65c4 GB |
1594 | Decl : Node_Id; |
1595 | Old_P : Entity_Id; | |
1596 | Old_Bod : Node_Id; | |
1597 | Old_Spec : Entity_Id; | |
1598 | ||
df3e68b1 | 1599 | C_Names : constant array (1 .. 4) of Name_Id := |
07fc65c4 GB |
1600 | (Name_Initialize, |
1601 | Name_Adjust, | |
df3e68b1 HK |
1602 | Name_Finalize, |
1603 | Name_Finalize_Address); | |
07fc65c4 | 1604 | |
df3e68b1 | 1605 | D_Names : constant array (1 .. 4) of TSS_Name_Type := |
fbf5a39b AC |
1606 | (TSS_Deep_Initialize, |
1607 | TSS_Deep_Adjust, | |
df3e68b1 HK |
1608 | TSS_Deep_Finalize, |
1609 | TSS_Finalize_Address); | |
07fc65c4 GB |
1610 | |
1611 | begin | |
0e41a941 AC |
1612 | -- Remove previous controlled function which was constructed and |
1613 | -- analyzed when the type was frozen. This requires removing the | |
1614 | -- body of the redefined primitive, as well as its specification | |
1615 | -- if needed (there is no spec created for Deep_Initialize, see | |
1616 | -- exp_ch3.adb). We must also dismantle the exception information | |
1617 | -- that may have been generated for it when front end zero-cost | |
1618 | -- tables are enabled. | |
07fc65c4 GB |
1619 | |
1620 | for J in D_Names'Range loop | |
1621 | Old_P := TSS (Tagged_Type, D_Names (J)); | |
1622 | ||
1623 | if Present (Old_P) | |
1624 | and then Chars (Subp) = C_Names (J) | |
1625 | then | |
1626 | Old_Bod := Unit_Declaration_Node (Old_P); | |
1627 | Remove (Old_Bod); | |
1628 | Set_Is_Eliminated (Old_P); | |
1629 | Set_Scope (Old_P, Scope (Current_Scope)); | |
1630 | ||
1631 | if Nkind (Old_Bod) = N_Subprogram_Body | |
1632 | and then Present (Corresponding_Spec (Old_Bod)) | |
1633 | then | |
1634 | Old_Spec := Corresponding_Spec (Old_Bod); | |
1635 | Set_Has_Completion (Old_Spec, False); | |
07fc65c4 | 1636 | end if; |
07fc65c4 GB |
1637 | end if; |
1638 | end loop; | |
1639 | ||
1640 | Build_Late_Proc (Tagged_Type, Chars (Subp)); | |
1641 | ||
0e41a941 AC |
1642 | -- The new operation is added to the actions of the freeze node |
1643 | -- for the type, but this node has already been analyzed, so we | |
1644 | -- must retrieve and analyze explicitly the new body. | |
07fc65c4 GB |
1645 | |
1646 | if Present (F_Node) | |
1647 | and then Present (Actions (F_Node)) | |
1648 | then | |
1649 | Decl := Last (Actions (F_Node)); | |
1650 | Analyze (Decl); | |
1651 | end if; | |
1652 | end; | |
1653 | end if; | |
48c8c473 AC |
1654 | |
1655 | -- For similarity with record extensions, in Ada 9X the language should | |
1656 | -- have disallowed adding visible operations to a tagged type after | |
1657 | -- deriving a private extension from it. Report a warning if this | |
1658 | -- primitive is defined after a private extension of Tagged_Type. | |
1659 | ||
1660 | Warn_On_Late_Primitive_After_Private_Extension (Tagged_Type, Subp); | |
996ae0b0 RK |
1661 | end Check_Dispatching_Operation; |
1662 | ||
1663 | ------------------------------------------ | |
1664 | -- Check_Operation_From_Incomplete_Type -- | |
1665 | ------------------------------------------ | |
1666 | ||
1667 | procedure Check_Operation_From_Incomplete_Type | |
1668 | (Subp : Entity_Id; | |
1669 | Typ : Entity_Id) | |
1670 | is | |
1671 | Full : constant Entity_Id := Full_View (Typ); | |
1672 | Parent_Typ : constant Entity_Id := Etype (Full); | |
1673 | Old_Prim : constant Elist_Id := Primitive_Operations (Parent_Typ); | |
1674 | New_Prim : constant Elist_Id := Primitive_Operations (Full); | |
1675 | Op1, Op2 : Elmt_Id; | |
1676 | Prev : Elmt_Id := No_Elmt; | |
1677 | ||
4637729f AC |
1678 | function Derives_From (Parent_Subp : Entity_Id) return Boolean; |
1679 | -- Check that Subp has profile of an operation derived from Parent_Subp. | |
1680 | -- Subp must have a parameter or result type that is Typ or an access | |
1681 | -- parameter or access result type that designates Typ. | |
996ae0b0 RK |
1682 | |
1683 | ------------------ | |
1684 | -- Derives_From -- | |
1685 | ------------------ | |
1686 | ||
4637729f | 1687 | function Derives_From (Parent_Subp : Entity_Id) return Boolean is |
996ae0b0 RK |
1688 | F1, F2 : Entity_Id; |
1689 | ||
1690 | begin | |
4637729f | 1691 | if Chars (Parent_Subp) /= Chars (Subp) then |
996ae0b0 RK |
1692 | return False; |
1693 | end if; | |
1694 | ||
4637729f AC |
1695 | -- Check that the type of controlling formals is derived from the |
1696 | -- parent subprogram's controlling formal type (or designated type | |
1697 | -- if the formal type is an anonymous access type). | |
1698 | ||
1699 | F1 := First_Formal (Parent_Subp); | |
996ae0b0 | 1700 | F2 := First_Formal (Subp); |
996ae0b0 | 1701 | while Present (F1) and then Present (F2) loop |
996ae0b0 | 1702 | if Ekind (Etype (F1)) = E_Anonymous_Access_Type then |
996ae0b0 RK |
1703 | if Ekind (Etype (F2)) /= E_Anonymous_Access_Type then |
1704 | return False; | |
996ae0b0 RK |
1705 | elsif Designated_Type (Etype (F1)) = Parent_Typ |
1706 | and then Designated_Type (Etype (F2)) /= Full | |
1707 | then | |
1708 | return False; | |
1709 | end if; | |
1710 | ||
1711 | elsif Ekind (Etype (F2)) = E_Anonymous_Access_Type then | |
1712 | return False; | |
1713 | ||
4637729f | 1714 | elsif Etype (F1) = Parent_Typ and then Etype (F2) /= Full then |
996ae0b0 RK |
1715 | return False; |
1716 | end if; | |
1717 | ||
1718 | Next_Formal (F1); | |
1719 | Next_Formal (F2); | |
1720 | end loop; | |
1721 | ||
4637729f AC |
1722 | -- Check that a controlling result type is derived from the parent |
1723 | -- subprogram's result type (or designated type if the result type | |
1724 | -- is an anonymous access type). | |
1725 | ||
1726 | if Ekind (Parent_Subp) = E_Function then | |
1727 | if Ekind (Subp) /= E_Function then | |
1728 | return False; | |
1729 | ||
1730 | elsif Ekind (Etype (Parent_Subp)) = E_Anonymous_Access_Type then | |
1731 | if Ekind (Etype (Subp)) /= E_Anonymous_Access_Type then | |
1732 | return False; | |
1733 | ||
1734 | elsif Designated_Type (Etype (Parent_Subp)) = Parent_Typ | |
1735 | and then Designated_Type (Etype (Subp)) /= Full | |
1736 | then | |
1737 | return False; | |
1738 | end if; | |
1739 | ||
1740 | elsif Ekind (Etype (Subp)) = E_Anonymous_Access_Type then | |
1741 | return False; | |
1742 | ||
1743 | elsif Etype (Parent_Subp) = Parent_Typ | |
1744 | and then Etype (Subp) /= Full | |
1745 | then | |
1746 | return False; | |
1747 | end if; | |
1748 | ||
1749 | elsif Ekind (Subp) = E_Function then | |
1750 | return False; | |
1751 | end if; | |
1752 | ||
996ae0b0 RK |
1753 | return No (F1) and then No (F2); |
1754 | end Derives_From; | |
1755 | ||
1756 | -- Start of processing for Check_Operation_From_Incomplete_Type | |
1757 | ||
1758 | begin | |
1759 | -- The operation may override an inherited one, or may be a new one | |
1760 | -- altogether. The inherited operation will have been hidden by the | |
1761 | -- current one at the point of the type derivation, so it does not | |
1762 | -- appear in the list of primitive operations of the type. We have to | |
1763 | -- find the proper place of insertion in the list of primitive opera- | |
1764 | -- tions by iterating over the list for the parent type. | |
1765 | ||
1766 | Op1 := First_Elmt (Old_Prim); | |
1767 | Op2 := First_Elmt (New_Prim); | |
996ae0b0 | 1768 | while Present (Op1) and then Present (Op2) loop |
996ae0b0 | 1769 | if Derives_From (Node (Op1)) then |
996ae0b0 | 1770 | if No (Prev) then |
ce2b6ba5 | 1771 | |
a90bd866 | 1772 | -- Avoid adding it to the list of primitives if already there |
ce2b6ba5 JM |
1773 | |
1774 | if Node (Op2) /= Subp then | |
1775 | Prepend_Elmt (Subp, New_Prim); | |
1776 | end if; | |
1777 | ||
996ae0b0 RK |
1778 | else |
1779 | Insert_Elmt_After (Subp, Prev); | |
1780 | end if; | |
1781 | ||
1782 | return; | |
1783 | end if; | |
1784 | ||
1785 | Prev := Op2; | |
1786 | Next_Elmt (Op1); | |
1787 | Next_Elmt (Op2); | |
1788 | end loop; | |
1789 | ||
fbf5a39b | 1790 | -- Operation is a new primitive |
996ae0b0 RK |
1791 | |
1792 | Append_Elmt (Subp, New_Prim); | |
996ae0b0 RK |
1793 | end Check_Operation_From_Incomplete_Type; |
1794 | ||
1795 | --------------------------------------- | |
1796 | -- Check_Operation_From_Private_View -- | |
1797 | --------------------------------------- | |
1798 | ||
1799 | procedure Check_Operation_From_Private_View (Subp, Old_Subp : Entity_Id) is | |
1800 | Tagged_Type : Entity_Id; | |
1801 | ||
1802 | begin | |
1803 | if Is_Dispatching_Operation (Alias (Subp)) then | |
1804 | Set_Scope (Subp, Current_Scope); | |
1805 | Tagged_Type := Find_Dispatching_Type (Subp); | |
1806 | ||
01957849 | 1807 | -- Add Old_Subp to primitive operations if not already present |
20e8cdd7 | 1808 | |
996ae0b0 | 1809 | if Present (Tagged_Type) and then Is_Tagged_Type (Tagged_Type) then |
9057bd6a | 1810 | Add_Dispatching_Operation (Tagged_Type, Old_Subp); |
996ae0b0 | 1811 | |
243cae0a AC |
1812 | -- If Old_Subp isn't already marked as dispatching then this is |
1813 | -- the case of an operation of an untagged private type fulfilled | |
1814 | -- by a tagged type that overrides an inherited dispatching | |
1815 | -- operation, so we set the necessary dispatching attributes here. | |
996ae0b0 RK |
1816 | |
1817 | if not Is_Dispatching_Operation (Old_Subp) then | |
fbf5a39b AC |
1818 | |
1819 | -- If the untagged type has no discriminants, and the full | |
243cae0a AC |
1820 | -- view is constrained, there will be a spurious mismatch of |
1821 | -- subtypes on the controlling arguments, because the tagged | |
fbf5a39b AC |
1822 | -- type is the internal base type introduced in the derivation. |
1823 | -- Use the original type to verify conformance, rather than the | |
1824 | -- base type. | |
1825 | ||
1826 | if not Comes_From_Source (Tagged_Type) | |
1827 | and then Has_Discriminants (Tagged_Type) | |
1828 | then | |
1829 | declare | |
1830 | Formal : Entity_Id; | |
0e41a941 | 1831 | |
fbf5a39b AC |
1832 | begin |
1833 | Formal := First_Formal (Old_Subp); | |
1834 | while Present (Formal) loop | |
1835 | if Tagged_Type = Base_Type (Etype (Formal)) then | |
1836 | Tagged_Type := Etype (Formal); | |
1837 | end if; | |
1838 | ||
1839 | Next_Formal (Formal); | |
1840 | end loop; | |
1841 | end; | |
1842 | ||
1843 | if Tagged_Type = Base_Type (Etype (Old_Subp)) then | |
1844 | Tagged_Type := Etype (Old_Subp); | |
1845 | end if; | |
1846 | end if; | |
1847 | ||
996ae0b0 RK |
1848 | Check_Controlling_Formals (Tagged_Type, Old_Subp); |
1849 | Set_Is_Dispatching_Operation (Old_Subp, True); | |
024d33d8 | 1850 | Set_DT_Position_Value (Old_Subp, No_Uint); |
996ae0b0 RK |
1851 | end if; |
1852 | ||
1853 | -- If the old subprogram is an explicit renaming of some other | |
1854 | -- entity, it is not overridden by the inherited subprogram. | |
1855 | -- Otherwise, update its alias and other attributes. | |
1856 | ||
1857 | if Present (Alias (Old_Subp)) | |
0e41a941 AC |
1858 | and then Nkind (Unit_Declaration_Node (Old_Subp)) /= |
1859 | N_Subprogram_Renaming_Declaration | |
996ae0b0 RK |
1860 | then |
1861 | Set_Alias (Old_Subp, Alias (Subp)); | |
1862 | ||
03459f40 AC |
1863 | -- The derived subprogram should inherit the abstractness of |
1864 | -- the parent subprogram (except in the case of a function | |
996ae0b0 | 1865 | -- returning the type). This sets the abstractness properly |
03459f40 AC |
1866 | -- for cases where a private extension may have inherited an |
1867 | -- abstract operation, but the full type is derived from a | |
1868 | -- descendant type and inherits a nonabstract version. | |
996ae0b0 RK |
1869 | |
1870 | if Etype (Subp) /= Tagged_Type then | |
dee4682a JM |
1871 | Set_Is_Abstract_Subprogram |
1872 | (Old_Subp, Is_Abstract_Subprogram (Alias (Subp))); | |
996ae0b0 RK |
1873 | end if; |
1874 | end if; | |
1875 | end if; | |
1876 | end if; | |
1877 | end Check_Operation_From_Private_View; | |
1878 | ||
1879 | -------------------------- | |
1880 | -- Find_Controlling_Arg -- | |
1881 | -------------------------- | |
1882 | ||
1883 | function Find_Controlling_Arg (N : Node_Id) return Node_Id is | |
1884 | Orig_Node : constant Node_Id := Original_Node (N); | |
1885 | Typ : Entity_Id; | |
1886 | ||
1887 | begin | |
1888 | if Nkind (Orig_Node) = N_Qualified_Expression then | |
1889 | return Find_Controlling_Arg (Expression (Orig_Node)); | |
1890 | end if; | |
1891 | ||
ca14fd02 ES |
1892 | -- Dispatching on result case. If expansion is disabled, the node still |
1893 | -- has the structure of a function call. However, if the function name | |
1894 | -- is an operator and the call was given in infix form, the original | |
1895 | -- node has no controlling result and we must examine the current node. | |
1896 | ||
1897 | if Nkind (N) = N_Function_Call | |
1898 | and then Present (Controlling_Argument (N)) | |
1899 | and then Has_Controlling_Result (Entity (Name (N))) | |
1900 | then | |
1901 | return Controlling_Argument (N); | |
1902 | ||
1903 | -- If expansion is enabled, the call may have been transformed into | |
1904 | -- an indirect call, and we need to recover the original node. | |
996ae0b0 | 1905 | |
ca14fd02 | 1906 | elsif Nkind (Orig_Node) = N_Function_Call |
996ae0b0 RK |
1907 | and then Present (Controlling_Argument (Orig_Node)) |
1908 | and then Has_Controlling_Result (Entity (Name (Orig_Node))) | |
1909 | then | |
1910 | return Controlling_Argument (Orig_Node); | |
1911 | ||
5dcab3ca AC |
1912 | -- Type conversions are dynamically tagged if the target type, or its |
1913 | -- designated type, are classwide. An interface conversion expands into | |
1914 | -- a dereference, so test must be performed on the original node. | |
1915 | ||
1916 | elsif Nkind (Orig_Node) = N_Type_Conversion | |
1917 | and then Nkind (N) = N_Explicit_Dereference | |
1918 | and then Is_Controlling_Actual (N) | |
1919 | then | |
1920 | declare | |
1921 | Target_Type : constant Entity_Id := | |
1922 | Entity (Subtype_Mark (Orig_Node)); | |
1923 | ||
1924 | begin | |
1925 | if Is_Class_Wide_Type (Target_Type) then | |
1926 | return N; | |
1927 | ||
1928 | elsif Is_Access_Type (Target_Type) | |
1929 | and then Is_Class_Wide_Type (Designated_Type (Target_Type)) | |
1930 | then | |
1931 | return N; | |
1932 | ||
1933 | else | |
1934 | return Empty; | |
1935 | end if; | |
1936 | end; | |
1937 | ||
996ae0b0 RK |
1938 | -- Normal case |
1939 | ||
fbf5a39b AC |
1940 | elsif Is_Controlling_Actual (N) |
1941 | or else | |
1942 | (Nkind (Parent (N)) = N_Qualified_Expression | |
1943 | and then Is_Controlling_Actual (Parent (N))) | |
1944 | then | |
996ae0b0 RK |
1945 | Typ := Etype (N); |
1946 | ||
1947 | if Is_Access_Type (Typ) then | |
0e41a941 AC |
1948 | |
1949 | -- In the case of an Access attribute, use the type of the prefix, | |
1950 | -- since in the case of an actual for an access parameter, the | |
1951 | -- attribute's type may be of a specific designated type, even | |
1952 | -- though the prefix type is class-wide. | |
996ae0b0 RK |
1953 | |
1954 | if Nkind (N) = N_Attribute_Reference then | |
1955 | Typ := Etype (Prefix (N)); | |
07fc65c4 | 1956 | |
0e41a941 AC |
1957 | -- An allocator is dispatching if the type of qualified expression |
1958 | -- is class_wide, in which case this is the controlling type. | |
07fc65c4 GB |
1959 | |
1960 | elsif Nkind (Orig_Node) = N_Allocator | |
1961 | and then Nkind (Expression (Orig_Node)) = N_Qualified_Expression | |
1962 | then | |
1963 | Typ := Etype (Expression (Orig_Node)); | |
996ae0b0 RK |
1964 | else |
1965 | Typ := Designated_Type (Typ); | |
1966 | end if; | |
1967 | end if; | |
1968 | ||
fbf5a39b AC |
1969 | if Is_Class_Wide_Type (Typ) |
1970 | or else | |
1971 | (Nkind (Parent (N)) = N_Qualified_Expression | |
1972 | and then Is_Access_Type (Etype (N)) | |
1973 | and then Is_Class_Wide_Type (Designated_Type (Etype (N)))) | |
1974 | then | |
996ae0b0 RK |
1975 | return N; |
1976 | end if; | |
1977 | end if; | |
1978 | ||
1979 | return Empty; | |
1980 | end Find_Controlling_Arg; | |
1981 | ||
1982 | --------------------------- | |
1983 | -- Find_Dispatching_Type -- | |
1984 | --------------------------- | |
1985 | ||
1986 | function Find_Dispatching_Type (Subp : Entity_Id) return Entity_Id is | |
ee9aa7b6 | 1987 | A_Formal : Entity_Id; |
996ae0b0 RK |
1988 | Formal : Entity_Id; |
1989 | Ctrl_Type : Entity_Id; | |
1990 | ||
1991 | begin | |
22a83cea AC |
1992 | if Ekind_In (Subp, E_Function, E_Procedure) |
1993 | and then Present (DTC_Entity (Subp)) | |
1994 | then | |
996ae0b0 RK |
1995 | return Scope (DTC_Entity (Subp)); |
1996 | ||
ee9aa7b6 AC |
1997 | -- For subprograms internally generated by derivations of tagged types |
1998 | -- use the alias subprogram as a reference to locate the dispatching | |
e1b871e9 | 1999 | -- type of Subp. |
ee9aa7b6 AC |
2000 | |
2001 | elsif not Comes_From_Source (Subp) | |
2002 | and then Present (Alias (Subp)) | |
2003 | and then Is_Dispatching_Operation (Alias (Subp)) | |
2004 | then | |
2005 | if Ekind (Alias (Subp)) = E_Function | |
2006 | and then Has_Controlling_Result (Alias (Subp)) | |
2007 | then | |
2008 | return Check_Controlling_Type (Etype (Subp), Subp); | |
2009 | ||
2010 | else | |
2011 | Formal := First_Formal (Subp); | |
2012 | A_Formal := First_Formal (Alias (Subp)); | |
2013 | while Present (A_Formal) loop | |
2014 | if Is_Controlling_Formal (A_Formal) then | |
2015 | return Check_Controlling_Type (Etype (Formal), Subp); | |
2016 | end if; | |
2017 | ||
2018 | Next_Formal (Formal); | |
2019 | Next_Formal (A_Formal); | |
2020 | end loop; | |
2021 | ||
2022 | pragma Assert (False); | |
2023 | return Empty; | |
2024 | end if; | |
2025 | ||
2026 | -- General case | |
2027 | ||
996ae0b0 RK |
2028 | else |
2029 | Formal := First_Formal (Subp); | |
2030 | while Present (Formal) loop | |
2031 | Ctrl_Type := Check_Controlling_Type (Etype (Formal), Subp); | |
2032 | ||
2033 | if Present (Ctrl_Type) then | |
2034 | return Ctrl_Type; | |
2035 | end if; | |
2036 | ||
2037 | Next_Formal (Formal); | |
2038 | end loop; | |
2039 | ||
ee9aa7b6 | 2040 | -- The subprogram may also be dispatching on result |
996ae0b0 RK |
2041 | |
2042 | if Present (Etype (Subp)) then | |
ee9aa7b6 | 2043 | return Check_Controlling_Type (Etype (Subp), Subp); |
996ae0b0 RK |
2044 | end if; |
2045 | end if; | |
2046 | ||
0e41a941 | 2047 | pragma Assert (not Is_Dispatching_Operation (Subp)); |
996ae0b0 RK |
2048 | return Empty; |
2049 | end Find_Dispatching_Type; | |
2050 | ||
ea034236 AC |
2051 | -------------------------------------- |
2052 | -- Find_Hidden_Overridden_Primitive -- | |
2053 | -------------------------------------- | |
2054 | ||
2055 | function Find_Hidden_Overridden_Primitive (S : Entity_Id) return Entity_Id | |
2056 | is | |
2057 | Tag_Typ : constant Entity_Id := Find_Dispatching_Type (S); | |
2058 | Elmt : Elmt_Id; | |
2059 | Orig_Prim : Entity_Id; | |
2060 | Prim : Entity_Id; | |
2061 | Vis_List : Elist_Id; | |
2062 | ||
2063 | begin | |
57081559 AC |
2064 | -- This Ada 2012 rule applies only for type extensions or private |
2065 | -- extensions, where the parent type is not in a parent unit, and | |
2066 | -- where an operation is never declared but still inherited. | |
ea034236 AC |
2067 | |
2068 | if No (Tag_Typ) | |
2069 | or else not Is_Record_Type (Tag_Typ) | |
2070 | or else Etype (Tag_Typ) = Tag_Typ | |
57081559 | 2071 | or else In_Open_Scopes (Scope (Etype (Tag_Typ))) |
ea034236 AC |
2072 | then |
2073 | return Empty; | |
2074 | end if; | |
2075 | ||
2076 | -- Collect the list of visible ancestor of the tagged type | |
2077 | ||
2078 | Vis_List := Visible_Ancestors (Tag_Typ); | |
2079 | ||
2080 | Elmt := First_Elmt (Primitive_Operations (Tag_Typ)); | |
2081 | while Present (Elmt) loop | |
2082 | Prim := Node (Elmt); | |
2083 | ||
2084 | -- Find an inherited hidden dispatching primitive with the name of S | |
329b9f81 | 2085 | -- and a type-conformant profile. |
ea034236 AC |
2086 | |
2087 | if Present (Alias (Prim)) | |
2088 | and then Is_Hidden (Alias (Prim)) | |
2089 | and then Find_Dispatching_Type (Alias (Prim)) /= Tag_Typ | |
2090 | and then Primitive_Names_Match (S, Prim) | |
2091 | and then Type_Conformant (S, Prim) | |
2092 | then | |
2093 | declare | |
2094 | Vis_Ancestor : Elmt_Id; | |
2095 | Elmt : Elmt_Id; | |
2096 | ||
2097 | begin | |
2098 | -- The original corresponding operation of Prim must be an | |
243cae0a AC |
2099 | -- operation of a visible ancestor of the dispatching type S, |
2100 | -- and the original corresponding operation of S2 must be | |
2101 | -- visible. | |
ea034236 AC |
2102 | |
2103 | Orig_Prim := Original_Corresponding_Operation (Prim); | |
2104 | ||
2105 | if Orig_Prim /= Prim | |
2106 | and then Is_Immediately_Visible (Orig_Prim) | |
2107 | then | |
2108 | Vis_Ancestor := First_Elmt (Vis_List); | |
ea034236 AC |
2109 | while Present (Vis_Ancestor) loop |
2110 | Elmt := | |
2111 | First_Elmt (Primitive_Operations (Node (Vis_Ancestor))); | |
2112 | while Present (Elmt) loop | |
2113 | if Node (Elmt) = Orig_Prim then | |
2114 | Set_Overridden_Operation (S, Prim); | |
2115 | Set_Alias (Prim, Orig_Prim); | |
ea034236 AC |
2116 | return Prim; |
2117 | end if; | |
2118 | ||
2119 | Next_Elmt (Elmt); | |
2120 | end loop; | |
2121 | ||
2122 | Next_Elmt (Vis_Ancestor); | |
2123 | end loop; | |
2124 | end if; | |
2125 | end; | |
2126 | end if; | |
2127 | ||
2128 | Next_Elmt (Elmt); | |
2129 | end loop; | |
2130 | ||
2131 | return Empty; | |
2132 | end Find_Hidden_Overridden_Primitive; | |
2133 | ||
ce2b6ba5 JM |
2134 | --------------------------------------- |
2135 | -- Find_Primitive_Covering_Interface -- | |
2136 | --------------------------------------- | |
2137 | ||
2138 | function Find_Primitive_Covering_Interface | |
2139 | (Tagged_Type : Entity_Id; | |
2140 | Iface_Prim : Entity_Id) return Entity_Id | |
2141 | is | |
92817e89 AC |
2142 | E : Entity_Id; |
2143 | El : Elmt_Id; | |
ce2b6ba5 JM |
2144 | |
2145 | begin | |
2146 | pragma Assert (Is_Interface (Find_Dispatching_Type (Iface_Prim)) | |
2147 | or else (Present (Alias (Iface_Prim)) | |
329b9f81 AC |
2148 | and then |
2149 | Is_Interface | |
2150 | (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim))))); | |
ce2b6ba5 | 2151 | |
947430d5 AC |
2152 | -- Search in the homonym chain. Done to speed up locating visible |
2153 | -- entities and required to catch primitives associated with the partial | |
2154 | -- view of private types when processing the corresponding full view. | |
92817e89 | 2155 | |
ce2b6ba5 JM |
2156 | E := Current_Entity (Iface_Prim); |
2157 | while Present (E) loop | |
2158 | if Is_Subprogram (E) | |
2159 | and then Is_Dispatching_Operation (E) | |
2160 | and then Is_Interface_Conformant (Tagged_Type, Iface_Prim, E) | |
2161 | then | |
2162 | return E; | |
2163 | end if; | |
2164 | ||
2165 | E := Homonym (E); | |
2166 | end loop; | |
2167 | ||
03459f40 AC |
2168 | -- Search in the list of primitives of the type. Required to locate |
2169 | -- the covering primitive if the covering primitive is not visible | |
2170 | -- (for example, non-visible inherited primitive of private type). | |
92817e89 AC |
2171 | |
2172 | El := First_Elmt (Primitive_Operations (Tagged_Type)); | |
2173 | while Present (El) loop | |
2174 | E := Node (El); | |
2175 | ||
947430d5 AC |
2176 | -- Keep separate the management of internal entities that link |
2177 | -- primitives with interface primitives from tagged type primitives. | |
2178 | ||
2179 | if No (Interface_Alias (E)) then | |
2180 | if Present (Alias (E)) then | |
2181 | ||
2182 | -- This interface primitive has not been covered yet | |
2183 | ||
2184 | if Alias (E) = Iface_Prim then | |
2185 | return E; | |
2186 | ||
2187 | -- The covering primitive was inherited | |
2188 | ||
2189 | elsif Overridden_Operation (Ultimate_Alias (E)) | |
2190 | = Iface_Prim | |
2191 | then | |
2192 | return E; | |
2193 | end if; | |
2194 | end if; | |
2195 | ||
ce09f8b3 | 2196 | -- Check if E covers the interface primitive (includes case in |
878f708a | 2197 | -- which E is an inherited private primitive). |
ce09f8b3 AC |
2198 | |
2199 | if Is_Interface_Conformant (Tagged_Type, Iface_Prim, E) then | |
2200 | return E; | |
2201 | end if; | |
2202 | ||
947430d5 | 2203 | -- Use the internal entity that links the interface primitive with |
329b9f81 | 2204 | -- the covering primitive to locate the entity. |
947430d5 AC |
2205 | |
2206 | elsif Interface_Alias (E) = Iface_Prim then | |
2207 | return Alias (E); | |
92817e89 AC |
2208 | end if; |
2209 | ||
2210 | Next_Elmt (El); | |
2211 | end loop; | |
2212 | ||
2213 | -- Not found | |
2214 | ||
ce2b6ba5 JM |
2215 | return Empty; |
2216 | end Find_Primitive_Covering_Interface; | |
2217 | ||
beacce02 | 2218 | --------------------------- |
cc821e65 | 2219 | -- Inheritance_Utilities -- |
beacce02 AC |
2220 | --------------------------- |
2221 | ||
cc821e65 | 2222 | package body Inheritance_Utilities is |
beacce02 | 2223 | |
cc821e65 CD |
2224 | --------------------------- |
2225 | -- Inherited_Subprograms -- | |
2226 | --------------------------- | |
beacce02 | 2227 | |
cc821e65 CD |
2228 | function Inherited_Subprograms |
2229 | (S : Entity_Id; | |
2230 | No_Interfaces : Boolean := False; | |
2231 | Interfaces_Only : Boolean := False; | |
2232 | One_Only : Boolean := False) return Subprogram_List | |
2233 | is | |
2234 | Result : Subprogram_List (1 .. 6000); | |
2235 | -- 6000 here is intended to be infinity. We could use an expandable | |
2236 | -- table, but it would be awfully heavy, and there is no way that we | |
2237 | -- could reasonably exceed this value. | |
beacce02 | 2238 | |
f537fc00 | 2239 | N : Nat := 0; |
cc821e65 | 2240 | -- Number of entries in Result |
1fb00064 | 2241 | |
cc821e65 CD |
2242 | Parent_Op : Entity_Id; |
2243 | -- Traverses the Overridden_Operation chain | |
1fb00064 | 2244 | |
cc821e65 CD |
2245 | procedure Store_IS (E : Entity_Id); |
2246 | -- Stores E in Result if not already stored | |
1fb00064 | 2247 | |
cc821e65 CD |
2248 | -------------- |
2249 | -- Store_IS -- | |
2250 | -------------- | |
1fb00064 | 2251 | |
cc821e65 CD |
2252 | procedure Store_IS (E : Entity_Id) is |
2253 | begin | |
2254 | for J in 1 .. N loop | |
2255 | if E = Result (J) then | |
2256 | return; | |
2257 | end if; | |
2258 | end loop; | |
1fb00064 | 2259 | |
cc821e65 CD |
2260 | N := N + 1; |
2261 | Result (N) := E; | |
2262 | end Store_IS; | |
eefe9555 | 2263 | |
f537fc00 | 2264 | -- Start of processing for Inherited_Subprograms |
beacce02 | 2265 | |
cc821e65 CD |
2266 | begin |
2267 | pragma Assert (not (No_Interfaces and Interfaces_Only)); | |
beacce02 | 2268 | |
cc821e65 CD |
2269 | -- When used from backends, visibility can be handled differently |
2270 | -- resulting in no dispatching type being found. | |
eefe9555 | 2271 | |
cc821e65 CD |
2272 | if Present (S) |
2273 | and then Is_Dispatching_Operation (S) | |
2274 | and then Present (Find_DT (S)) | |
2275 | then | |
cc821e65 CD |
2276 | -- Deal with direct inheritance |
2277 | ||
2278 | if not Interfaces_Only then | |
2279 | Parent_Op := S; | |
2280 | loop | |
2281 | Parent_Op := Overridden_Operation (Parent_Op); | |
2282 | exit when No (Parent_Op) | |
f537fc00 HK |
2283 | or else (No_Interfaces |
2284 | and then Is_Interface (Find_DT (Parent_Op))); | |
cc821e65 CD |
2285 | |
2286 | if Is_Subprogram_Or_Generic_Subprogram (Parent_Op) then | |
2287 | Store_IS (Parent_Op); | |
2288 | ||
2289 | if One_Only then | |
2290 | goto Done; | |
2291 | end if; | |
3a37ecec | 2292 | end if; |
cc821e65 CD |
2293 | end loop; |
2294 | end if; | |
beacce02 | 2295 | |
cc821e65 | 2296 | -- Now deal with interfaces |
1fb00064 | 2297 | |
cc821e65 CD |
2298 | if not No_Interfaces then |
2299 | declare | |
2300 | Tag_Typ : Entity_Id; | |
2301 | Prim : Entity_Id; | |
2302 | Elmt : Elmt_Id; | |
1fb00064 | 2303 | |
cc821e65 CD |
2304 | begin |
2305 | Tag_Typ := Find_DT (S); | |
1fb00064 | 2306 | |
cc821e65 CD |
2307 | -- In the presence of limited views there may be no visible |
2308 | -- dispatching type. Primitives will be inherited when non- | |
2309 | -- limited view is frozen. | |
167b47d9 | 2310 | |
cc821e65 CD |
2311 | if No (Tag_Typ) then |
2312 | return Result (1 .. 0); | |
2313 | end if; | |
167b47d9 | 2314 | |
cc821e65 CD |
2315 | if Is_Concurrent_Type (Tag_Typ) then |
2316 | Tag_Typ := Corresponding_Record_Type (Tag_Typ); | |
2317 | end if; | |
beacce02 | 2318 | |
cc821e65 | 2319 | -- Search primitive operations of dispatching type |
1fb00064 | 2320 | |
cc821e65 CD |
2321 | if Present (Tag_Typ) |
2322 | and then Present (Primitive_Operations (Tag_Typ)) | |
2323 | then | |
2324 | Elmt := First_Elmt (Primitive_Operations (Tag_Typ)); | |
2325 | while Present (Elmt) loop | |
2326 | Prim := Node (Elmt); | |
1fb00064 | 2327 | |
cc821e65 CD |
2328 | -- The following test eliminates some odd cases in |
2329 | -- which Ekind (Prim) is Void, to be investigated | |
2330 | -- further ??? | |
1fb00064 | 2331 | |
cc821e65 CD |
2332 | if not Is_Subprogram_Or_Generic_Subprogram (Prim) then |
2333 | null; | |
1fb00064 | 2334 | |
cc821e65 CD |
2335 | -- For [generic] subprogram, look at interface |
2336 | -- alias. | |
1fb00064 | 2337 | |
cc821e65 CD |
2338 | elsif Present (Interface_Alias (Prim)) |
2339 | and then Alias (Prim) = S | |
2340 | then | |
2341 | -- We have found a primitive covered by S | |
1fb00064 | 2342 | |
cc821e65 | 2343 | Store_IS (Interface_Alias (Prim)); |
3a37ecec | 2344 | |
cc821e65 CD |
2345 | if One_Only then |
2346 | goto Done; | |
2347 | end if; | |
3a37ecec | 2348 | end if; |
1fb00064 | 2349 | |
cc821e65 CD |
2350 | Next_Elmt (Elmt); |
2351 | end loop; | |
2352 | end if; | |
2353 | end; | |
2354 | end if; | |
eefe9555 | 2355 | end if; |
beacce02 | 2356 | |
cc821e65 CD |
2357 | <<Done>> |
2358 | ||
2359 | return Result (1 .. N); | |
2360 | end Inherited_Subprograms; | |
3a37ecec | 2361 | |
cc821e65 CD |
2362 | ------------------------------ |
2363 | -- Is_Overriding_Subprogram -- | |
2364 | ------------------------------ | |
2365 | ||
2366 | function Is_Overriding_Subprogram (E : Entity_Id) return Boolean is | |
2367 | Inherited : constant Subprogram_List := | |
2368 | Inherited_Subprograms (E, One_Only => True); | |
2369 | begin | |
2370 | return Inherited'Length > 0; | |
2371 | end Is_Overriding_Subprogram; | |
2372 | end Inheritance_Utilities; | |
2373 | ||
2374 | -------------------------------- | |
2375 | -- Inheritance_Utilities_Inst -- | |
2376 | -------------------------------- | |
2377 | ||
2378 | package Inheritance_Utilities_Inst is new | |
2379 | Inheritance_Utilities (Find_Dispatching_Type); | |
2380 | ||
2381 | --------------------------- | |
2382 | -- Inherited_Subprograms -- | |
2383 | --------------------------- | |
2384 | ||
2385 | function Inherited_Subprograms | |
2386 | (S : Entity_Id; | |
2387 | No_Interfaces : Boolean := False; | |
2388 | Interfaces_Only : Boolean := False; | |
2389 | One_Only : Boolean := False) return Subprogram_List renames | |
2390 | Inheritance_Utilities_Inst.Inherited_Subprograms; | |
beacce02 | 2391 | |
996ae0b0 RK |
2392 | --------------------------- |
2393 | -- Is_Dynamically_Tagged -- | |
2394 | --------------------------- | |
2395 | ||
2396 | function Is_Dynamically_Tagged (N : Node_Id) return Boolean is | |
2397 | begin | |
f9c0d38c JM |
2398 | if Nkind (N) = N_Error then |
2399 | return False; | |
b6dd03dd ES |
2400 | |
2401 | elsif Present (Find_Controlling_Arg (N)) then | |
2402 | return True; | |
2403 | ||
3b506eef | 2404 | -- Special cases: entities, and calls that dispatch on result |
b6dd03dd ES |
2405 | |
2406 | elsif Is_Entity_Name (N) then | |
2407 | return Is_Class_Wide_Type (Etype (N)); | |
2408 | ||
2409 | elsif Nkind (N) = N_Function_Call | |
2410 | and then Is_Class_Wide_Type (Etype (N)) | |
2411 | then | |
2412 | return True; | |
2413 | ||
3b506eef | 2414 | -- Otherwise check whether call has controlling argument |
b6dd03dd | 2415 | |
f9c0d38c | 2416 | else |
b6dd03dd | 2417 | return False; |
f9c0d38c | 2418 | end if; |
996ae0b0 RK |
2419 | end Is_Dynamically_Tagged; |
2420 | ||
0052da20 JM |
2421 | --------------------------------- |
2422 | -- Is_Null_Interface_Primitive -- | |
2423 | --------------------------------- | |
2424 | ||
2425 | function Is_Null_Interface_Primitive (E : Entity_Id) return Boolean is | |
2426 | begin | |
2427 | return Comes_From_Source (E) | |
2428 | and then Is_Dispatching_Operation (E) | |
2429 | and then Ekind (E) = E_Procedure | |
2430 | and then Null_Present (Parent (E)) | |
2431 | and then Is_Interface (Find_Dispatching_Type (E)); | |
2432 | end Is_Null_Interface_Primitive; | |
2433 | ||
7b4ebba5 AC |
2434 | ----------------------------------- |
2435 | -- Is_Inherited_Public_Operation -- | |
2436 | ----------------------------------- | |
2437 | ||
2438 | function Is_Inherited_Public_Operation (Op : Entity_Id) return Boolean is | |
9ac3cbb3 | 2439 | Pack_Decl : Node_Id; |
7cc7f3aa PMR |
2440 | Prim : Entity_Id := Op; |
2441 | Scop : Entity_Id := Prim; | |
7b4ebba5 AC |
2442 | |
2443 | begin | |
7cc7f3aa PMR |
2444 | -- Locate the ultimate non-hidden alias entity |
2445 | ||
2446 | while Present (Alias (Prim)) and then not Is_Hidden (Alias (Prim)) loop | |
2447 | pragma Assert (Alias (Prim) /= Prim); | |
2448 | Prim := Alias (Prim); | |
2449 | Scop := Scope (Prim); | |
2450 | end loop; | |
2451 | ||
7b4ebba5 AC |
2452 | if Comes_From_Source (Prim) and then Ekind (Scop) = E_Package then |
2453 | Pack_Decl := Unit_Declaration_Node (Scop); | |
9ac3cbb3 PMR |
2454 | |
2455 | return | |
2456 | Nkind (Pack_Decl) = N_Package_Declaration | |
2457 | and then List_Containing (Unit_Declaration_Node (Prim)) = | |
2458 | Visible_Declarations (Specification (Pack_Decl)); | |
7b4ebba5 AC |
2459 | |
2460 | else | |
2461 | return False; | |
2462 | end if; | |
2463 | end Is_Inherited_Public_Operation; | |
2464 | ||
90a4b336 YM |
2465 | ------------------------------ |
2466 | -- Is_Overriding_Subprogram -- | |
2467 | ------------------------------ | |
2468 | ||
cc821e65 CD |
2469 | function Is_Overriding_Subprogram (E : Entity_Id) return Boolean renames |
2470 | Inheritance_Utilities_Inst.Is_Overriding_Subprogram; | |
90a4b336 | 2471 | |
996ae0b0 RK |
2472 | -------------------------- |
2473 | -- Is_Tag_Indeterminate -- | |
2474 | -------------------------- | |
2475 | ||
2476 | function Is_Tag_Indeterminate (N : Node_Id) return Boolean is | |
2477 | Nam : Entity_Id; | |
2478 | Actual : Node_Id; | |
2479 | Orig_Node : constant Node_Id := Original_Node (N); | |
2480 | ||
2481 | begin | |
2482 | if Nkind (Orig_Node) = N_Function_Call | |
2483 | and then Is_Entity_Name (Name (Orig_Node)) | |
2484 | then | |
2485 | Nam := Entity (Name (Orig_Node)); | |
2486 | ||
2487 | if not Has_Controlling_Result (Nam) then | |
2488 | return False; | |
2489 | ||
243cae0a AC |
2490 | -- The function may have a controlling result, but if the return type |
2491 | -- is not visibly tagged, then this is not tag-indeterminate. | |
2492 | ||
2493 | elsif Is_Access_Type (Etype (Nam)) | |
2494 | and then not Is_Tagged_Type (Designated_Type (Etype (Nam))) | |
2495 | then | |
2496 | return False; | |
2497 | ||
fbf5a39b AC |
2498 | -- An explicit dereference means that the call has already been |
2499 | -- expanded and there is no tag to propagate. | |
2500 | ||
2501 | elsif Nkind (N) = N_Explicit_Dereference then | |
2502 | return False; | |
2503 | ||
996ae0b0 RK |
2504 | -- If there are no actuals, the call is tag-indeterminate |
2505 | ||
2506 | elsif No (Parameter_Associations (Orig_Node)) then | |
2507 | return True; | |
2508 | ||
2509 | else | |
2510 | Actual := First_Actual (Orig_Node); | |
996ae0b0 RK |
2511 | while Present (Actual) loop |
2512 | if Is_Controlling_Actual (Actual) | |
2513 | and then not Is_Tag_Indeterminate (Actual) | |
2514 | then | |
243cae0a AC |
2515 | -- One operand is dispatching |
2516 | ||
2517 | return False; | |
996ae0b0 RK |
2518 | end if; |
2519 | ||
2520 | Next_Actual (Actual); | |
2521 | end loop; | |
2522 | ||
2523 | return True; | |
996ae0b0 RK |
2524 | end if; |
2525 | ||
2526 | elsif Nkind (Orig_Node) = N_Qualified_Expression then | |
2527 | return Is_Tag_Indeterminate (Expression (Orig_Node)); | |
2528 | ||
3bcd6930 JM |
2529 | -- Case of a call to the Input attribute (possibly rewritten), which is |
2530 | -- always tag-indeterminate except when its prefix is a Class attribute. | |
2531 | ||
2532 | elsif Nkind (Orig_Node) = N_Attribute_Reference | |
2533 | and then | |
2534 | Get_Attribute_Id (Attribute_Name (Orig_Node)) = Attribute_Input | |
7b4ebba5 | 2535 | and then Nkind (Prefix (Orig_Node)) /= N_Attribute_Reference |
3bcd6930 JM |
2536 | then |
2537 | return True; | |
67f3c450 | 2538 | |
243cae0a AC |
2539 | -- In Ada 2005, a function that returns an anonymous access type can be |
2540 | -- dispatching, and the dereference of a call to such a function can | |
2541 | -- also be tag-indeterminate if the call itself is. | |
67f3c450 HK |
2542 | |
2543 | elsif Nkind (Orig_Node) = N_Explicit_Dereference | |
0791fbe9 | 2544 | and then Ada_Version >= Ada_2005 |
67f3c450 HK |
2545 | then |
2546 | return Is_Tag_Indeterminate (Prefix (Orig_Node)); | |
2547 | ||
996ae0b0 RK |
2548 | else |
2549 | return False; | |
2550 | end if; | |
2551 | end Is_Tag_Indeterminate; | |
2552 | ||
2553 | ------------------------------------ | |
2554 | -- Override_Dispatching_Operation -- | |
2555 | ------------------------------------ | |
2556 | ||
2557 | procedure Override_Dispatching_Operation | |
2558 | (Tagged_Type : Entity_Id; | |
2559 | Prev_Op : Entity_Id; | |
8398e82e AC |
2560 | New_Op : Entity_Id; |
2561 | Is_Wrapper : Boolean := False) | |
996ae0b0 | 2562 | is |
67f3c450 HK |
2563 | Elmt : Elmt_Id; |
2564 | Prim : Node_Id; | |
996ae0b0 RK |
2565 | |
2566 | begin | |
3bcd6930 | 2567 | -- Diagnose failure to match No_Return in parent (Ada-2005, AI-414, but |
a90bd866 | 2568 | -- we do it unconditionally in Ada 95 now, since this is our pragma). |
3bcd6930 JM |
2569 | |
2570 | if No_Return (Prev_Op) and then not No_Return (New_Op) then | |
2571 | Error_Msg_N ("procedure & must have No_Return pragma", New_Op); | |
2572 | Error_Msg_N ("\since overridden procedure has No_Return", New_Op); | |
2573 | end if; | |
2574 | ||
67f3c450 HK |
2575 | -- If there is no previous operation to override, the type declaration |
2576 | -- was malformed, and an error must have been emitted already. | |
996ae0b0 | 2577 | |
67f3c450 | 2578 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); |
7b4ebba5 | 2579 | while Present (Elmt) and then Node (Elmt) /= Prev_Op loop |
67f3c450 | 2580 | Next_Elmt (Elmt); |
996ae0b0 RK |
2581 | end loop; |
2582 | ||
67f3c450 | 2583 | if No (Elmt) then |
996ae0b0 RK |
2584 | return; |
2585 | end if; | |
2586 | ||
74853971 AC |
2587 | -- The location of entities that come from source in the list of |
2588 | -- primitives of the tagged type must follow their order of occurrence | |
308e6f3a | 2589 | -- in the sources to fulfill the C++ ABI. If the overridden entity is a |
05dbd302 AC |
2590 | -- primitive of an interface that is not implemented by the parents of |
2591 | -- this tagged type (that is, it is an alias of an interface primitive | |
2592 | -- generated by Derive_Interface_Progenitors), then we must append the | |
2593 | -- new entity at the end of the list of primitives. | |
74853971 AC |
2594 | |
2595 | if Present (Alias (Prev_Op)) | |
05dbd302 | 2596 | and then Etype (Tagged_Type) /= Tagged_Type |
74853971 AC |
2597 | and then Is_Interface (Find_Dispatching_Type (Alias (Prev_Op))) |
2598 | and then not Is_Ancestor (Find_Dispatching_Type (Alias (Prev_Op)), | |
4ac2477e | 2599 | Tagged_Type, Use_Full_View => True) |
05dbd302 AC |
2600 | and then not Implements_Interface |
2601 | (Etype (Tagged_Type), | |
2602 | Find_Dispatching_Type (Alias (Prev_Op))) | |
74853971 AC |
2603 | then |
2604 | Remove_Elmt (Primitive_Operations (Tagged_Type), Elmt); | |
9057bd6a | 2605 | Add_Dispatching_Operation (Tagged_Type, New_Op); |
74853971 | 2606 | |
308e6f3a | 2607 | -- The new primitive replaces the overridden entity. Required to ensure |
74853971 AC |
2608 | -- that overriding primitive is assigned the same dispatch table slot. |
2609 | ||
2610 | else | |
2611 | Replace_Elmt (Elmt, New_Op); | |
2612 | end if; | |
3bcd6930 | 2613 | |
7b4ebba5 AC |
2614 | if Ada_Version >= Ada_2005 and then Has_Interfaces (Tagged_Type) then |
2615 | ||
67f3c450 | 2616 | -- Ada 2005 (AI-251): Update the attribute alias of all the aliased |
03459f40 AC |
2617 | -- entities of the overridden primitive to reference New_Op, and |
2618 | -- also propagate the proper value of Is_Abstract_Subprogram. Verify | |
ace980d5 ES |
2619 | -- that the new operation is subtype conformant with the interface |
2620 | -- operations that it implements (for operations inherited from the | |
2621 | -- parent itself, this check is made when building the derived type). | |
758c442c | 2622 | |
8398e82e AC |
2623 | -- Note: This code is executed with internally generated wrappers of |
2624 | -- functions with controlling result and late overridings. | |
ce2b6ba5 | 2625 | |
67f3c450 HK |
2626 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); |
2627 | while Present (Elmt) loop | |
2628 | Prim := Node (Elmt); | |
758c442c | 2629 | |
67f3c450 HK |
2630 | if Prim = New_Op then |
2631 | null; | |
758c442c | 2632 | |
f9c0d38c JM |
2633 | -- Note: The check on Is_Subprogram protects the frontend against |
2634 | -- reading attributes in entities that are not yet fully decorated | |
2635 | ||
2636 | elsif Is_Subprogram (Prim) | |
ce2b6ba5 | 2637 | and then Present (Interface_Alias (Prim)) |
67f3c450 HK |
2638 | and then Alias (Prim) = Prev_Op |
2639 | then | |
2640 | Set_Alias (Prim, New_Op); | |
758c442c | 2641 | |
8398e82e AC |
2642 | -- No further decoration needed yet for internally generated |
2643 | -- wrappers of controlling functions since (at this stage) | |
2644 | -- they are not yet decorated. | |
2645 | ||
2646 | if not Is_Wrapper then | |
2647 | Check_Subtype_Conformant (New_Op, Prim); | |
2648 | ||
2649 | Set_Is_Abstract_Subprogram (Prim, | |
2650 | Is_Abstract_Subprogram (New_Op)); | |
67f3c450 | 2651 | |
8398e82e AC |
2652 | -- Ensure that this entity will be expanded to fill the |
2653 | -- corresponding entry in its dispatch table. | |
2654 | ||
2655 | if not Is_Abstract_Subprogram (Prim) then | |
2656 | Set_Has_Delayed_Freeze (Prim); | |
2657 | end if; | |
67f3c450 | 2658 | end if; |
758c442c GD |
2659 | end if; |
2660 | ||
2661 | Next_Elmt (Elmt); | |
2662 | end loop; | |
758c442c | 2663 | end if; |
996ae0b0 | 2664 | |
5dcc05e6 | 2665 | if (not Is_Package_Or_Generic_Package (Current_Scope)) |
996ae0b0 RK |
2666 | or else not In_Private_Part (Current_Scope) |
2667 | then | |
2668 | -- Not a private primitive | |
2669 | ||
2670 | null; | |
2671 | ||
2672 | else pragma Assert (Is_Inherited_Operation (Prev_Op)); | |
2673 | ||
2674 | -- Make the overriding operation into an alias of the implicit one. | |
3bcd6930 | 2675 | -- In this fashion a call from outside ends up calling the new body |
329b9f81 AC |
2676 | -- even if non-dispatching, and a call from inside calls the over- |
2677 | -- riding operation because it hides the implicit one. To indicate | |
2678 | -- that the body of Prev_Op is never called, set its dispatch table | |
2679 | -- entity to Empty. If the overridden operation has a dispatching | |
2680 | -- result, so does the overriding one. | |
996ae0b0 RK |
2681 | |
2682 | Set_Alias (Prev_Op, New_Op); | |
2683 | Set_DTC_Entity (Prev_Op, Empty); | |
c6f39437 | 2684 | Set_Has_Controlling_Result (New_Op, Has_Controlling_Result (Prev_Op)); |
996ae0b0 RK |
2685 | return; |
2686 | end if; | |
2687 | end Override_Dispatching_Operation; | |
2688 | ||
2689 | ------------------- | |
2690 | -- Propagate_Tag -- | |
2691 | ------------------- | |
2692 | ||
2693 | procedure Propagate_Tag (Control : Node_Id; Actual : Node_Id) is | |
2694 | Call_Node : Node_Id; | |
2695 | Arg : Node_Id; | |
2696 | ||
2697 | begin | |
2698 | if Nkind (Actual) = N_Function_Call then | |
2699 | Call_Node := Actual; | |
2700 | ||
2701 | elsif Nkind (Actual) = N_Identifier | |
2702 | and then Nkind (Original_Node (Actual)) = N_Function_Call | |
2703 | then | |
0e41a941 AC |
2704 | -- Call rewritten as object declaration when stack-checking is |
2705 | -- enabled. Propagate tag to expression in declaration, which is | |
2706 | -- original call. | |
996ae0b0 RK |
2707 | |
2708 | Call_Node := Expression (Parent (Entity (Actual))); | |
2709 | ||
67f3c450 HK |
2710 | -- Ada 2005: If this is a dereference of a call to a function with a |
2711 | -- dispatching access-result, the tag is propagated when the dereference | |
2712 | -- itself is expanded (see exp_ch6.adb) and there is nothing else to do. | |
2713 | ||
2714 | elsif Nkind (Actual) = N_Explicit_Dereference | |
2715 | and then Nkind (Original_Node (Prefix (Actual))) = N_Function_Call | |
2716 | then | |
2717 | return; | |
2718 | ||
11fa950b AC |
2719 | -- When expansion is suppressed, an unexpanded call to 'Input can occur, |
2720 | -- and in that case we can simply return. | |
2721 | ||
2722 | elsif Nkind (Actual) = N_Attribute_Reference then | |
2723 | pragma Assert (Attribute_Name (Actual) = Name_Input); | |
2724 | ||
2725 | return; | |
2726 | ||
3bcd6930 JM |
2727 | -- Only other possibilities are parenthesized or qualified expression, |
2728 | -- or an expander-generated unchecked conversion of a function call to | |
2729 | -- a stream Input attribute. | |
996ae0b0 RK |
2730 | |
2731 | else | |
2732 | Call_Node := Expression (Actual); | |
2733 | end if; | |
2734 | ||
7af1cf83 AC |
2735 | -- No action needed if the call has been already expanded |
2736 | ||
2737 | if Is_Expanded_Dispatching_Call (Call_Node) then | |
2738 | return; | |
2739 | end if; | |
2740 | ||
0e41a941 AC |
2741 | -- Do not set the Controlling_Argument if already set. This happens in |
2742 | -- the special case of _Input (see Exp_Attr, case Input). | |
996ae0b0 RK |
2743 | |
2744 | if No (Controlling_Argument (Call_Node)) then | |
2745 | Set_Controlling_Argument (Call_Node, Control); | |
2746 | end if; | |
2747 | ||
2748 | Arg := First_Actual (Call_Node); | |
996ae0b0 RK |
2749 | while Present (Arg) loop |
2750 | if Is_Tag_Indeterminate (Arg) then | |
2751 | Propagate_Tag (Control, Arg); | |
2752 | end if; | |
2753 | ||
2754 | Next_Actual (Arg); | |
2755 | end loop; | |
2756 | ||
535a8637 | 2757 | -- Expansion of dispatching calls is suppressed on VM targets, because |
0e41a941 AC |
2758 | -- the VM back-ends directly handle the generation of dispatching calls |
2759 | -- and would have to undo any expansion to an indirect call. | |
996ae0b0 | 2760 | |
1f110335 | 2761 | if Tagged_Type_Expansion then |
d69cf005 AC |
2762 | declare |
2763 | Call_Typ : constant Entity_Id := Etype (Call_Node); | |
2764 | ||
2765 | begin | |
2766 | Expand_Dispatching_Call (Call_Node); | |
2767 | ||
2768 | -- If the controlling argument is an interface type and the type | |
2769 | -- of Call_Node differs then we must add an implicit conversion to | |
2770 | -- force displacement of the pointer to the object to reference | |
2771 | -- the secondary dispatch table of the interface. | |
2772 | ||
2773 | if Is_Interface (Etype (Control)) | |
2774 | and then Etype (Control) /= Call_Typ | |
2775 | then | |
2776 | -- Cannot use Convert_To because the previous call to | |
2777 | -- Expand_Dispatching_Call leaves decorated the Call_Node | |
2778 | -- with the type of Control. | |
2779 | ||
2780 | Rewrite (Call_Node, | |
2781 | Make_Type_Conversion (Sloc (Call_Node), | |
2782 | Subtype_Mark => | |
2783 | New_Occurrence_Of (Etype (Control), Sloc (Call_Node)), | |
2784 | Expression => Relocate_Node (Call_Node))); | |
2785 | Set_Etype (Call_Node, Etype (Control)); | |
2786 | Set_Analyzed (Call_Node); | |
2787 | ||
f6f4d8d4 | 2788 | Expand_Interface_Conversion (Call_Node); |
d69cf005 AC |
2789 | end if; |
2790 | end; | |
f7d5442e ES |
2791 | |
2792 | -- Expansion of a dispatching call results in an indirect call, which in | |
2793 | -- turn causes current values to be killed (see Resolve_Call), so on VM | |
2794 | -- targets we do the call here to ensure consistent warnings between VM | |
2795 | -- and non-VM targets. | |
2796 | ||
2797 | else | |
2798 | Kill_Current_Values; | |
996ae0b0 RK |
2799 | end if; |
2800 | end Propagate_Tag; | |
2801 | ||
2802 | end Sem_Disp; |