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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 | -- -- | |
8d0d46f4 | 9 | -- Copyright (C) 1992-2021, 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 | ||
104f58db BD |
26 | with Aspects; use Aspects; |
27 | with Atree; use Atree; | |
28 | with Debug; use Debug; | |
29 | with Elists; use Elists; | |
30 | with Einfo; use Einfo; | |
76f9c7f4 | 31 | with Einfo.Entities; use Einfo.Entities; |
104f58db BD |
32 | with Einfo.Utils; use Einfo.Utils; |
33 | with Exp_Disp; use Exp_Disp; | |
34 | with Exp_Util; use Exp_Util; | |
35 | with Exp_Ch7; use Exp_Ch7; | |
36 | with Exp_Tss; use Exp_Tss; | |
37 | with Errout; use Errout; | |
38 | with Lib.Xref; use Lib.Xref; | |
39 | with Namet; use Namet; | |
40 | with Nlists; use Nlists; | |
41 | with Nmake; use Nmake; | |
42 | with Opt; use Opt; | |
43 | with Output; use Output; | |
44 | with Restrict; use Restrict; | |
45 | with Rident; use Rident; | |
46 | with Sem; use Sem; | |
47 | with Sem_Aux; use Sem_Aux; | |
104f58db BD |
48 | with Sem_Ch6; use Sem_Ch6; |
49 | with Sem_Ch8; use Sem_Ch8; | |
50 | with Sem_Eval; use Sem_Eval; | |
51 | with Sem_Type; use Sem_Type; | |
52 | with Sem_Util; use Sem_Util; | |
53 | with Snames; use Snames; | |
54 | with Sinfo; use Sinfo; | |
55 | with Sinfo.Nodes; use Sinfo.Nodes; | |
56 | with Sinfo.Utils; use Sinfo.Utils; | |
57 | with Tbuild; use Tbuild; | |
58 | with Uintp; use Uintp; | |
59 | with Warnsw; use Warnsw; | |
996ae0b0 RK |
60 | |
61 | package body Sem_Disp is | |
62 | ||
63 | ----------------------- | |
64 | -- Local Subprograms -- | |
65 | ----------------------- | |
66 | ||
996ae0b0 RK |
67 | procedure Add_Dispatching_Operation |
68 | (Tagged_Type : Entity_Id; | |
69 | New_Op : Entity_Id); | |
70 | -- Add New_Op in the list of primitive operations of Tagged_Type | |
71 | ||
72 | function Check_Controlling_Type | |
73 | (T : Entity_Id; | |
15ce9ca2 | 74 | Subp : Entity_Id) return Entity_Id; |
82c80734 RD |
75 | -- T is the tagged type of a formal parameter or the result of Subp. |
76 | -- If the subprogram has a controlling parameter or result that matches | |
77 | -- the type, then returns the tagged type of that parameter or result | |
78 | -- (returning the designated tagged type in the case of an access | |
79 | -- parameter); otherwise returns empty. | |
996ae0b0 | 80 | |
ea034236 AC |
81 | function Find_Hidden_Overridden_Primitive (S : Entity_Id) return Entity_Id; |
82 | -- [Ada 2012:AI-0125] Find an inherited hidden primitive of the dispatching | |
83 | -- type of S that has the same name of S, a type-conformant profile, an | |
84 | -- original corresponding operation O that is a primitive of a visible | |
85 | -- ancestor of the dispatching type of S and O is visible at the point of | |
86 | -- of declaration of S. If the entity is found the Alias of S is set to the | |
87 | -- original corresponding operation S and its Overridden_Operation is set | |
88 | -- to the found entity; otherwise return Empty. | |
89 | -- | |
90 | -- This routine does not search for non-hidden primitives since they are | |
91 | -- covered by the normal Ada 2005 rules. | |
92 | ||
7b4ebba5 AC |
93 | function Is_Inherited_Public_Operation (Op : Entity_Id) return Boolean; |
94 | -- Check whether a primitive operation is inherited from an operation | |
95 | -- declared in the visible part of its package. | |
96 | ||
15ce9ca2 AC |
97 | ------------------------------- |
98 | -- Add_Dispatching_Operation -- | |
99 | ------------------------------- | |
996ae0b0 RK |
100 | |
101 | procedure Add_Dispatching_Operation | |
102 | (Tagged_Type : Entity_Id; | |
103 | New_Op : Entity_Id) | |
104 | is | |
105 | List : constant Elist_Id := Primitive_Operations (Tagged_Type); | |
20e8cdd7 | 106 | |
996ae0b0 | 107 | begin |
550f4135 AC |
108 | -- The dispatching operation may already be on the list, if it is the |
109 | -- wrapper for an inherited function of a null extension (see Exp_Ch3 | |
20e8cdd7 GD |
110 | -- for the construction of function wrappers). The list of primitive |
111 | -- operations must not contain duplicates. | |
112 | ||
9057bd6a HK |
113 | -- The Default_Initial_Condition and invariant procedures are not added |
114 | -- to the list of primitives even when they are generated for a tagged | |
115 | -- type. These routines must not be targets of dispatching calls and | |
116 | -- therefore must not appear in the dispatch table because they already | |
117 | -- utilize class-wide-precondition semantics to handle inheritance and | |
118 | -- overriding. | |
119 | ||
120 | if Is_Suitable_Primitive (New_Op) then | |
121 | Append_Unique_Elmt (New_Op, List); | |
122 | end if; | |
996ae0b0 RK |
123 | end Add_Dispatching_Operation; |
124 | ||
904a2ae4 AC |
125 | -------------------------- |
126 | -- Covered_Interface_Op -- | |
127 | -------------------------- | |
0052da20 | 128 | |
904a2ae4 | 129 | function Covered_Interface_Op (Prim : Entity_Id) return Entity_Id is |
0052da20 JM |
130 | Tagged_Type : constant Entity_Id := Find_Dispatching_Type (Prim); |
131 | Elmt : Elmt_Id; | |
132 | E : Entity_Id; | |
133 | ||
134 | begin | |
135 | pragma Assert (Is_Dispatching_Operation (Prim)); | |
136 | ||
137 | -- Although this is a dispatching primitive we must check if its | |
138 | -- dispatching type is available because it may be the primitive | |
139 | -- of a private type not defined as tagged in its partial view. | |
140 | ||
141 | if Present (Tagged_Type) and then Has_Interfaces (Tagged_Type) then | |
142 | ||
143 | -- If the tagged type is frozen then the internal entities associated | |
144 | -- with interfaces are available in the list of primitives of the | |
145 | -- tagged type and can be used to speed up this search. | |
146 | ||
147 | if Is_Frozen (Tagged_Type) then | |
148 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); | |
149 | while Present (Elmt) loop | |
150 | E := Node (Elmt); | |
151 | ||
152 | if Present (Interface_Alias (E)) | |
153 | and then Alias (E) = Prim | |
154 | then | |
904a2ae4 | 155 | return Interface_Alias (E); |
0052da20 JM |
156 | end if; |
157 | ||
158 | Next_Elmt (Elmt); | |
159 | end loop; | |
160 | ||
161 | -- Otherwise we must collect all the interface primitives and check | |
904a2ae4 | 162 | -- if the Prim overrides (implements) some interface primitive. |
0052da20 JM |
163 | |
164 | else | |
165 | declare | |
166 | Ifaces_List : Elist_Id; | |
167 | Iface_Elmt : Elmt_Id; | |
168 | Iface : Entity_Id; | |
169 | Iface_Prim : Entity_Id; | |
170 | ||
171 | begin | |
172 | Collect_Interfaces (Tagged_Type, Ifaces_List); | |
173 | Iface_Elmt := First_Elmt (Ifaces_List); | |
174 | while Present (Iface_Elmt) loop | |
175 | Iface := Node (Iface_Elmt); | |
176 | ||
177 | Elmt := First_Elmt (Primitive_Operations (Iface)); | |
178 | while Present (Elmt) loop | |
179 | Iface_Prim := Node (Elmt); | |
180 | ||
904a2ae4 | 181 | if Chars (Iface_Prim) = Chars (Prim) |
0052da20 JM |
182 | and then Is_Interface_Conformant |
183 | (Tagged_Type, Iface_Prim, Prim) | |
184 | then | |
904a2ae4 | 185 | return Iface_Prim; |
0052da20 JM |
186 | end if; |
187 | ||
188 | Next_Elmt (Elmt); | |
189 | end loop; | |
190 | ||
191 | Next_Elmt (Iface_Elmt); | |
192 | end loop; | |
193 | end; | |
194 | end if; | |
195 | end if; | |
196 | ||
904a2ae4 AC |
197 | return Empty; |
198 | end Covered_Interface_Op; | |
0052da20 | 199 | |
996ae0b0 RK |
200 | ------------------------------- |
201 | -- Check_Controlling_Formals -- | |
202 | ------------------------------- | |
203 | ||
204 | procedure Check_Controlling_Formals | |
205 | (Typ : Entity_Id; | |
206 | Subp : Entity_Id) | |
207 | is | |
208 | Formal : Entity_Id; | |
209 | Ctrl_Type : Entity_Id; | |
996ae0b0 RK |
210 | |
211 | begin | |
212 | Formal := First_Formal (Subp); | |
996ae0b0 RK |
213 | while Present (Formal) loop |
214 | Ctrl_Type := Check_Controlling_Type (Etype (Formal), Subp); | |
215 | ||
216 | if Present (Ctrl_Type) then | |
eedc5882 | 217 | |
e3a79ce3 JS |
218 | -- Obtain the full type in case we are looking at an incomplete |
219 | -- view. | |
220 | ||
221 | if Ekind (Ctrl_Type) = E_Incomplete_Type | |
222 | and then Present (Full_View (Ctrl_Type)) | |
223 | then | |
224 | Ctrl_Type := Full_View (Ctrl_Type); | |
225 | end if; | |
8909e1ed | 226 | |
0e41a941 AC |
227 | -- When controlling type is concurrent and declared within a |
228 | -- generic or inside an instance use corresponding record type. | |
8909e1ed JM |
229 | |
230 | if Is_Concurrent_Type (Ctrl_Type) | |
231 | and then Present (Corresponding_Record_Type (Ctrl_Type)) | |
232 | then | |
233 | Ctrl_Type := Corresponding_Record_Type (Ctrl_Type); | |
234 | end if; | |
235 | ||
996ae0b0 RK |
236 | if Ctrl_Type = Typ then |
237 | Set_Is_Controlling_Formal (Formal); | |
238 | ||
0e41a941 | 239 | -- Ada 2005 (AI-231): Anonymous access types that are used in |
67f3c450 HK |
240 | -- controlling parameters exclude null because it is necessary |
241 | -- to read the tag to dispatch, and null has no tag. | |
9cca32af JM |
242 | |
243 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then | |
244 | Set_Can_Never_Be_Null (Etype (Formal)); | |
245 | Set_Is_Known_Non_Null (Etype (Formal)); | |
246 | end if; | |
247 | ||
996ae0b0 RK |
248 | -- Check that the parameter's nominal subtype statically |
249 | -- matches the first subtype. | |
250 | ||
251 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then | |
252 | if not Subtypes_Statically_Match | |
253 | (Typ, Designated_Type (Etype (Formal))) | |
254 | then | |
255 | Error_Msg_N | |
256 | ("parameter subtype does not match controlling type", | |
257 | Formal); | |
258 | end if; | |
259 | ||
6eca51ce ES |
260 | -- Within a predicate function, the formal may be a subtype |
261 | -- of a tagged type, given that the predicate is expressed | |
262 | -- in terms of the subtype. | |
263 | ||
264 | elsif not Subtypes_Statically_Match (Typ, Etype (Formal)) | |
265 | and then not Is_Predicate_Function (Subp) | |
266 | then | |
996ae0b0 RK |
267 | Error_Msg_N |
268 | ("parameter subtype does not match controlling type", | |
269 | Formal); | |
270 | end if; | |
271 | ||
272 | if Present (Default_Value (Formal)) then | |
20e8cdd7 GD |
273 | |
274 | -- In Ada 2005, access parameters can have defaults | |
275 | ||
276 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type | |
0791fbe9 | 277 | and then Ada_Version < Ada_2005 |
20e8cdd7 | 278 | then |
996ae0b0 RK |
279 | Error_Msg_N |
280 | ("default not allowed for controlling access parameter", | |
281 | Default_Value (Formal)); | |
282 | ||
283 | elsif not Is_Tag_Indeterminate (Default_Value (Formal)) then | |
284 | Error_Msg_N | |
285 | ("default expression must be a tag indeterminate" & | |
286 | " function call", Default_Value (Formal)); | |
287 | end if; | |
288 | end if; | |
289 | ||
290 | elsif Comes_From_Source (Subp) then | |
291 | Error_Msg_N | |
292 | ("operation can be dispatching in only one type", Subp); | |
293 | end if; | |
996ae0b0 RK |
294 | end if; |
295 | ||
296 | Next_Formal (Formal); | |
297 | end loop; | |
298 | ||
4a08c95c | 299 | if Ekind (Subp) in E_Function | E_Generic_Function then |
996ae0b0 RK |
300 | Ctrl_Type := Check_Controlling_Type (Etype (Subp), Subp); |
301 | ||
302 | if Present (Ctrl_Type) then | |
303 | if Ctrl_Type = Typ then | |
304 | Set_Has_Controlling_Result (Subp); | |
305 | ||
67f3c450 | 306 | -- Check that result subtype statically matches first subtype |
550f4135 | 307 | -- (Ada 2005): Subp may have a controlling access result. |
996ae0b0 | 308 | |
8909e1ed JM |
309 | if Subtypes_Statically_Match (Typ, Etype (Subp)) |
310 | or else (Ekind (Etype (Subp)) = E_Anonymous_Access_Type | |
311 | and then | |
312 | Subtypes_Statically_Match | |
313 | (Typ, Designated_Type (Etype (Subp)))) | |
314 | then | |
315 | null; | |
316 | ||
317 | else | |
996ae0b0 RK |
318 | Error_Msg_N |
319 | ("result subtype does not match controlling type", Subp); | |
320 | end if; | |
321 | ||
322 | elsif Comes_From_Source (Subp) then | |
323 | Error_Msg_N | |
324 | ("operation can be dispatching in only one type", Subp); | |
325 | end if; | |
996ae0b0 RK |
326 | end if; |
327 | end if; | |
328 | end Check_Controlling_Formals; | |
329 | ||
330 | ---------------------------- | |
331 | -- Check_Controlling_Type -- | |
332 | ---------------------------- | |
333 | ||
334 | function Check_Controlling_Type | |
335 | (T : Entity_Id; | |
15ce9ca2 | 336 | Subp : Entity_Id) return Entity_Id |
996ae0b0 RK |
337 | is |
338 | Tagged_Type : Entity_Id := Empty; | |
339 | ||
340 | begin | |
341 | if Is_Tagged_Type (T) then | |
342 | if Is_First_Subtype (T) then | |
343 | Tagged_Type := T; | |
344 | else | |
345 | Tagged_Type := Base_Type (T); | |
346 | end if; | |
347 | ||
ec6cfc5d AC |
348 | -- If the type is incomplete, it may have been declared without a |
349 | -- Tagged indication, but the full view may be tagged, in which case | |
350 | -- that is the controlling type of the subprogram. This is one of the | |
351 | -- approx. 579 places in the language where a lookahead would help. | |
352 | ||
353 | elsif Ekind (T) = E_Incomplete_Type | |
354 | and then Present (Full_View (T)) | |
355 | and then Is_Tagged_Type (Full_View (T)) | |
356 | then | |
357 | Set_Is_Tagged_Type (T); | |
358 | Tagged_Type := Full_View (T); | |
359 | ||
996ae0b0 RK |
360 | elsif Ekind (T) = E_Anonymous_Access_Type |
361 | and then Is_Tagged_Type (Designated_Type (T)) | |
996ae0b0 | 362 | then |
758c442c GD |
363 | if Ekind (Designated_Type (T)) /= E_Incomplete_Type then |
364 | if Is_First_Subtype (Designated_Type (T)) then | |
365 | Tagged_Type := Designated_Type (T); | |
366 | else | |
367 | Tagged_Type := Base_Type (Designated_Type (T)); | |
368 | end if; | |
369 | ||
550f4135 AC |
370 | -- Ada 2005: an incomplete type can be tagged. An operation with an |
371 | -- access parameter of the type is dispatching. | |
dee4682a JM |
372 | |
373 | elsif Scope (Designated_Type (T)) = Current_Scope then | |
374 | Tagged_Type := Designated_Type (T); | |
375 | ||
758c442c GD |
376 | -- Ada 2005 (AI-50217) |
377 | ||
7b56a91b | 378 | elsif From_Limited_With (Designated_Type (T)) |
47346923 | 379 | and then Has_Non_Limited_View (Designated_Type (T)) |
477cfc5b | 380 | and then Scope (Designated_Type (T)) = Scope (Subp) |
758c442c GD |
381 | then |
382 | if Is_First_Subtype (Non_Limited_View (Designated_Type (T))) then | |
383 | Tagged_Type := Non_Limited_View (Designated_Type (T)); | |
384 | else | |
385 | Tagged_Type := Base_Type (Non_Limited_View | |
386 | (Designated_Type (T))); | |
387 | end if; | |
996ae0b0 RK |
388 | end if; |
389 | end if; | |
390 | ||
550f4135 | 391 | if No (Tagged_Type) or else Is_Class_Wide_Type (Tagged_Type) then |
996ae0b0 RK |
392 | return Empty; |
393 | ||
550f4135 AC |
394 | -- The dispatching type and the primitive operation must be defined in |
395 | -- the same scope, except in the case of internal operations and formal | |
396 | -- abstract subprograms. | |
996ae0b0 | 397 | |
82c80734 RD |
398 | elsif ((Scope (Subp) = Scope (Tagged_Type) or else Is_Internal (Subp)) |
399 | and then (not Is_Generic_Type (Tagged_Type) | |
400 | or else not Comes_From_Source (Subp))) | |
401 | or else | |
dee4682a | 402 | (Is_Formal_Subprogram (Subp) and then Is_Abstract_Subprogram (Subp)) |
82c80734 RD |
403 | or else |
404 | (Nkind (Parent (Parent (Subp))) = N_Subprogram_Renaming_Declaration | |
405 | and then | |
406 | Present (Corresponding_Formal_Spec (Parent (Parent (Subp)))) | |
407 | and then | |
dee4682a | 408 | Is_Abstract_Subprogram (Subp)) |
996ae0b0 RK |
409 | then |
410 | return Tagged_Type; | |
411 | ||
412 | else | |
413 | return Empty; | |
414 | end if; | |
415 | end Check_Controlling_Type; | |
416 | ||
417 | ---------------------------- | |
418 | -- Check_Dispatching_Call -- | |
419 | ---------------------------- | |
420 | ||
421 | procedure Check_Dispatching_Call (N : Node_Id) is | |
8909e1ed | 422 | Loc : constant Source_Ptr := Sloc (N); |
82c80734 RD |
423 | Actual : Node_Id; |
424 | Formal : Entity_Id; | |
425 | Control : Node_Id := Empty; | |
426 | Func : Entity_Id; | |
427 | Subp_Entity : Entity_Id; | |
82c80734 | 428 | Indeterm_Ancestor_Call : Boolean := False; |
5612989e | 429 | Indeterm_Ctrl_Type : Entity_Id := Empty; -- init to avoid warning |
996ae0b0 | 430 | |
d215a13c ES |
431 | Static_Tag : Node_Id := Empty; |
432 | -- If a controlling formal has a statically tagged actual, the tag of | |
550f4135 | 433 | -- this actual is to be used for any tag-indeterminate actual. |
d215a13c | 434 | |
4f91a255 AC |
435 | procedure Check_Direct_Call; |
436 | -- In the case when the controlling actual is a class-wide type whose | |
437 | -- root type's completion is a task or protected type, the call is in | |
438 | -- fact direct. This routine detects the above case and modifies the | |
439 | -- call accordingly. | |
440 | ||
0d66b596 | 441 | procedure Check_Dispatching_Context (Call : Node_Id); |
996ae0b0 RK |
442 | -- If the call is tag-indeterminate and the entity being called is |
443 | -- abstract, verify that the context is a call that will eventually | |
444 | -- provide a tag for dispatching, or has provided one already. | |
445 | ||
4f91a255 AC |
446 | ----------------------- |
447 | -- Check_Direct_Call -- | |
448 | ----------------------- | |
449 | ||
450 | procedure Check_Direct_Call is | |
451 | Typ : Entity_Id := Etype (Control); | |
4f91a255 | 452 | begin |
03456e44 AC |
453 | -- Predefined primitives do not receive wrappers since they are built |
454 | -- from scratch for the corresponding record of synchronized types. | |
455 | -- Equality is in general predefined, but is excluded from the check | |
456 | -- when it is user-defined. | |
457 | ||
458 | if Is_Predefined_Dispatching_Operation (Subp_Entity) | |
459 | and then not Is_User_Defined_Equality (Subp_Entity) | |
460 | then | |
461 | return; | |
462 | end if; | |
463 | ||
4f91a255 AC |
464 | if Is_Class_Wide_Type (Typ) then |
465 | Typ := Root_Type (Typ); | |
466 | end if; | |
467 | ||
03456e44 AC |
468 | if Is_Private_Type (Typ) and then Present (Full_View (Typ)) then |
469 | Typ := Full_View (Typ); | |
470 | end if; | |
4f91a255 | 471 | |
03456e44 AC |
472 | if Is_Concurrent_Type (Typ) |
473 | and then | |
474 | Present (Corresponding_Record_Type (Typ)) | |
4f91a255 | 475 | then |
03456e44 | 476 | Typ := Corresponding_Record_Type (Typ); |
4f91a255 AC |
477 | |
478 | -- The concurrent record's list of primitives should contain a | |
479 | -- wrapper for the entity of the call, retrieve it. | |
480 | ||
481 | declare | |
482 | Prim : Entity_Id; | |
483 | Prim_Elmt : Elmt_Id; | |
484 | Wrapper_Found : Boolean := False; | |
485 | ||
486 | begin | |
487 | Prim_Elmt := First_Elmt (Primitive_Operations (Typ)); | |
488 | while Present (Prim_Elmt) loop | |
489 | Prim := Node (Prim_Elmt); | |
490 | ||
491 | if Is_Primitive_Wrapper (Prim) | |
492 | and then Wrapped_Entity (Prim) = Subp_Entity | |
493 | then | |
494 | Wrapper_Found := True; | |
495 | exit; | |
496 | end if; | |
497 | ||
498 | Next_Elmt (Prim_Elmt); | |
499 | end loop; | |
500 | ||
501 | -- A primitive declared between two views should have a | |
502 | -- corresponding wrapper. | |
503 | ||
504 | pragma Assert (Wrapper_Found); | |
505 | ||
506 | -- Modify the call by setting the proper entity | |
507 | ||
508 | Set_Entity (Name (N), Prim); | |
509 | end; | |
510 | end if; | |
511 | end Check_Direct_Call; | |
512 | ||
996ae0b0 RK |
513 | ------------------------------- |
514 | -- Check_Dispatching_Context -- | |
515 | ------------------------------- | |
516 | ||
0d66b596 AC |
517 | procedure Check_Dispatching_Context (Call : Node_Id) is |
518 | Subp : constant Entity_Id := Entity (Name (Call)); | |
996ae0b0 | 519 | |
8926d369 | 520 | procedure Abstract_Context_Error; |
03459f40 | 521 | -- Error for abstract call dispatching on result is not dispatching |
8926d369 | 522 | |
d2e59934 GD |
523 | function Has_Controlling_Current_Instance_Actual_In_DIC |
524 | (Call : Node_Id) return Boolean; | |
525 | -- Return True if the subprogram call Call has a controlling actual | |
526 | -- given directly by a current instance referenced within a DIC | |
527 | -- aspect. | |
528 | ||
03459f40 AC |
529 | ---------------------------- |
530 | -- Abstract_Context_Error -- | |
531 | ---------------------------- | |
8926d369 AC |
532 | |
533 | procedure Abstract_Context_Error is | |
534 | begin | |
535 | if Ekind (Subp) = E_Function then | |
536 | Error_Msg_N | |
537 | ("call to abstract function must be dispatching", N); | |
538 | ||
03459f40 AC |
539 | -- This error can occur for a procedure in the case of a call to |
540 | -- an abstract formal procedure with a statically tagged operand. | |
8926d369 AC |
541 | |
542 | else | |
543 | Error_Msg_N | |
87fd6836 | 544 | ("call to abstract procedure must be dispatching", N); |
8926d369 AC |
545 | end if; |
546 | end Abstract_Context_Error; | |
547 | ||
d2e59934 GD |
548 | ---------------------------------------- |
549 | -- Has_Current_Instance_Actual_In_DIC -- | |
550 | ---------------------------------------- | |
551 | ||
552 | function Has_Controlling_Current_Instance_Actual_In_DIC | |
553 | (Call : Node_Id) return Boolean | |
554 | is | |
555 | A : Node_Id; | |
556 | F : Entity_Id; | |
557 | begin | |
558 | F := First_Formal (Subp_Entity); | |
559 | A := First_Actual (Call); | |
560 | ||
561 | while Present (F) loop | |
562 | ||
563 | -- Return True if the actual denotes a current instance (which | |
564 | -- will be represented by an in-mode formal of the enclosing | |
565 | -- DIC_Procedure) passed to a controlling formal. We don't have | |
566 | -- to worry about controlling access formals here, because its | |
567 | -- illegal to apply Access (etc.) attributes to a current | |
568 | -- instance within an aspect (by AI12-0068). | |
569 | ||
570 | if Is_Controlling_Formal (F) | |
571 | and then Nkind (A) = N_Identifier | |
572 | and then Ekind (Entity (A)) = E_In_Parameter | |
573 | and then Is_Subprogram (Scope (Entity (A))) | |
574 | and then Is_DIC_Procedure (Scope (Entity (A))) | |
575 | then | |
576 | return True; | |
577 | end if; | |
578 | ||
579 | Next_Formal (F); | |
580 | Next_Actual (A); | |
581 | end loop; | |
582 | ||
583 | return False; | |
584 | end Has_Controlling_Current_Instance_Actual_In_DIC; | |
585 | ||
0d66b596 AC |
586 | -- Local variables |
587 | ||
87fd6836 AC |
588 | Scop : constant Entity_Id := Current_Scope_No_Loops; |
589 | Typ : constant Entity_Id := Etype (Subp); | |
590 | Par : Node_Id; | |
0d66b596 | 591 | |
03459f40 AC |
592 | -- Start of processing for Check_Dispatching_Context |
593 | ||
996ae0b0 | 594 | begin |
5f8d3dd5 AC |
595 | -- If the called subprogram is a private overriding, replace it |
596 | -- with its alias, which has the correct body. Verify that the | |
597 | -- two subprograms have the same controlling type (this is not the | |
598 | -- case for an inherited subprogram that has become abstract). | |
599 | ||
dee4682a | 600 | if Is_Abstract_Subprogram (Subp) |
0d66b596 | 601 | and then No (Controlling_Argument (Call)) |
996ae0b0 | 602 | then |
82c80734 | 603 | if Present (Alias (Subp)) |
dee4682a | 604 | and then not Is_Abstract_Subprogram (Alias (Subp)) |
82c80734 | 605 | and then No (DTC_Entity (Subp)) |
5f8d3dd5 | 606 | and then Find_Dispatching_Type (Subp) = |
245fee17 | 607 | Find_Dispatching_Type (Alias (Subp)) |
07fc65c4 | 608 | then |
550f4135 AC |
609 | -- Private overriding of inherited abstract operation, call is |
610 | -- legal. | |
996ae0b0 | 611 | |
82c80734 | 612 | Set_Entity (Name (N), Alias (Subp)); |
07fc65c4 | 613 | return; |
996ae0b0 | 614 | |
14212dc4 GD |
615 | -- If this is a pre/postcondition for an abstract subprogram, |
616 | -- it may call another abstract function that is a primitive | |
617 | -- of an abstract type. The call is nondispatching but will be | |
618 | -- legal in overridings of the operation. However, if the call | |
619 | -- is tag-indeterminate we want to continue with with the error | |
620 | -- checking below, as this case is illegal even for abstract | |
621 | -- subprograms (see AI12-0170). | |
622 | ||
623 | -- Similarly, as per AI12-0412, a nonabstract subprogram may | |
624 | -- have a class-wide pre/postcondition that includes a call to | |
625 | -- an abstract primitive of the subprogram's controlling type. | |
626 | -- Certain operations (nondispatching calls, 'Access, use as | |
627 | -- a generic actual) applied to such a nonabstract subprogram | |
628 | -- are illegal in the case where the type is abstract (see | |
629 | -- RM 6.1.1(18.2/5)). | |
630 | ||
631 | elsif Is_Subprogram (Scop) | |
632 | and then not Is_Tag_Indeterminate (N) | |
633 | and then In_Pre_Post_Condition (Call, Class_Wide_Only => True) | |
634 | ||
635 | -- The tagged type associated with the called subprogram must be | |
636 | -- the same as that of the subprogram with a class-wide aspect. | |
637 | ||
638 | and then Is_Dispatching_Operation (Scop) | |
87fd6836 | 639 | and then |
14212dc4 | 640 | Find_Dispatching_Type (Subp) = Find_Dispatching_Type (Scop) |
88ff8916 AC |
641 | then |
642 | null; | |
643 | ||
d2e59934 GD |
644 | -- Similarly to the dispensation for postconditions, a call to |
645 | -- an abstract function within a Default_Initial_Condition aspect | |
646 | -- can be legal when passed a current instance of the type. Such | |
647 | -- a call will be effectively mapped to a call to a primitive of | |
648 | -- a descendant type (see AI12-0397, as well as AI12-0170), so | |
649 | -- doesn't need to be dispatching. We test for being within a DIC | |
650 | -- procedure, since that's where the call will be analyzed. | |
651 | ||
652 | elsif Is_Subprogram (Scop) | |
653 | and then Is_DIC_Procedure (Scop) | |
654 | and then Has_Controlling_Current_Instance_Actual_In_DIC (Call) | |
655 | then | |
656 | null; | |
657 | ||
b6dd03dd | 658 | elsif Ekind (Current_Scope) = E_Function |
87fd6836 AC |
659 | and then Nkind (Unit_Declaration_Node (Scop)) = |
660 | N_Generic_Subprogram_Declaration | |
b6dd03dd ES |
661 | then |
662 | null; | |
663 | ||
07fc65c4 | 664 | else |
8926d369 AC |
665 | -- We need to determine whether the context of the call |
666 | -- provides a tag to make the call dispatching. This requires | |
667 | -- the call to be the actual in an enclosing call, and that | |
64ac53f4 | 668 | -- actual must be controlling. If the call is an operand of |
14212dc4 | 669 | -- equality, the other operand must not be abstract. |
8926d369 AC |
670 | |
671 | if not Is_Tagged_Type (Typ) | |
672 | and then not | |
0d66b596 AC |
673 | (Ekind (Typ) = E_Anonymous_Access_Type |
674 | and then Is_Tagged_Type (Designated_Type (Typ))) | |
8926d369 AC |
675 | then |
676 | Abstract_Context_Error; | |
677 | return; | |
678 | end if; | |
679 | ||
0d66b596 | 680 | Par := Parent (Call); |
03459f40 | 681 | |
8926d369 AC |
682 | if Nkind (Par) = N_Parameter_Association then |
683 | Par := Parent (Par); | |
684 | end if; | |
685 | ||
0d66b596 AC |
686 | if Nkind (Par) = N_Qualified_Expression |
687 | or else Nkind (Par) = N_Unchecked_Type_Conversion | |
688 | then | |
689 | Par := Parent (Par); | |
690 | end if; | |
8926d369 | 691 | |
612c48b1 | 692 | if Nkind (Par) in N_Subprogram_Call |
0d66b596 AC |
693 | and then Is_Entity_Name (Name (Par)) |
694 | then | |
695 | declare | |
696 | Enc_Subp : constant Entity_Id := Entity (Name (Par)); | |
697 | A : Node_Id; | |
698 | F : Entity_Id; | |
699 | Control : Entity_Id; | |
700 | Ret_Type : Entity_Id; | |
701 | ||
702 | begin | |
703 | -- Find controlling formal that can provide tag for the | |
704 | -- tag-indeterminate actual. The corresponding actual | |
705 | -- must be the corresponding class-wide type. | |
706 | ||
707 | F := First_Formal (Enc_Subp); | |
708 | A := First_Actual (Par); | |
709 | ||
710 | -- Find controlling type of call. Dereference if function | |
711 | -- returns an access type. | |
712 | ||
713 | Ret_Type := Etype (Call); | |
714 | if Is_Access_Type (Etype (Call)) then | |
715 | Ret_Type := Designated_Type (Ret_Type); | |
716 | end if; | |
ec6cfc5d | 717 | |
0d66b596 AC |
718 | while Present (F) loop |
719 | Control := Etype (A); | |
8926d369 | 720 | |
0d66b596 AC |
721 | if Is_Access_Type (Control) then |
722 | Control := Designated_Type (Control); | |
723 | end if; | |
07fc65c4 | 724 | |
0d66b596 AC |
725 | if Is_Controlling_Formal (F) |
726 | and then not (Call = A or else Parent (Call) = A) | |
727 | and then Control = Class_Wide_Type (Ret_Type) | |
728 | then | |
729 | return; | |
730 | end if; | |
82c80734 | 731 | |
0d66b596 AC |
732 | Next_Formal (F); |
733 | Next_Actual (A); | |
734 | end loop; | |
82c80734 | 735 | |
0d66b596 AC |
736 | if Nkind (Par) = N_Function_Call |
737 | and then Is_Tag_Indeterminate (Par) | |
8926d369 | 738 | then |
0d66b596 | 739 | -- The parent may be an actual of an enclosing call |
8926d369 | 740 | |
0d66b596 AC |
741 | Check_Dispatching_Context (Par); |
742 | return; | |
82c80734 | 743 | |
0d66b596 AC |
744 | else |
745 | Error_Msg_N | |
746 | ("call to abstract function must be dispatching", | |
747 | Call); | |
748 | return; | |
749 | end if; | |
750 | end; | |
8926d369 | 751 | |
0d66b596 AC |
752 | -- For equality operators, one of the operands must be |
753 | -- statically or dynamically tagged. | |
8926d369 | 754 | |
4a08c95c | 755 | elsif Nkind (Par) in N_Op_Eq | N_Op_Ne then |
0d66b596 AC |
756 | if N = Right_Opnd (Par) |
757 | and then Is_Tag_Indeterminate (Left_Opnd (Par)) | |
8926d369 | 758 | then |
0d66b596 | 759 | Abstract_Context_Error; |
8926d369 | 760 | |
0d66b596 AC |
761 | elsif N = Left_Opnd (Par) |
762 | and then Is_Tag_Indeterminate (Right_Opnd (Par)) | |
763 | then | |
8926d369 | 764 | Abstract_Context_Error; |
07fc65c4 | 765 | end if; |
0d66b596 AC |
766 | |
767 | return; | |
768 | ||
769 | -- The left-hand side of an assignment provides the tag | |
770 | ||
771 | elsif Nkind (Par) = N_Assignment_Statement then | |
772 | return; | |
773 | ||
774 | else | |
775 | Abstract_Context_Error; | |
776 | end if; | |
07fc65c4 | 777 | end if; |
996ae0b0 RK |
778 | end if; |
779 | end Check_Dispatching_Context; | |
780 | ||
781 | -- Start of processing for Check_Dispatching_Call | |
782 | ||
783 | begin | |
784 | -- Find a controlling argument, if any | |
785 | ||
786 | if Present (Parameter_Associations (N)) then | |
82c80734 | 787 | Subp_Entity := Entity (Name (N)); |
82c80734 | 788 | |
0e41a941 AC |
789 | Actual := First_Actual (N); |
790 | Formal := First_Formal (Subp_Entity); | |
996ae0b0 RK |
791 | while Present (Actual) loop |
792 | Control := Find_Controlling_Arg (Actual); | |
793 | exit when Present (Control); | |
82c80734 RD |
794 | |
795 | -- Check for the case where the actual is a tag-indeterminate call | |
796 | -- whose result type is different than the tagged type associated | |
797 | -- with the containing call, but is an ancestor of the type. | |
798 | ||
799 | if Is_Controlling_Formal (Formal) | |
800 | and then Is_Tag_Indeterminate (Actual) | |
801 | and then Base_Type (Etype (Actual)) /= Base_Type (Etype (Formal)) | |
802 | and then Is_Ancestor (Etype (Actual), Etype (Formal)) | |
803 | then | |
804 | Indeterm_Ancestor_Call := True; | |
805 | Indeterm_Ctrl_Type := Etype (Formal); | |
d215a13c ES |
806 | |
807 | -- If the formal is controlling but the actual is not, the type | |
808 | -- of the actual is statically known, and may be used as the | |
550f4135 | 809 | -- controlling tag for some other tag-indeterminate actual. |
d215a13c ES |
810 | |
811 | elsif Is_Controlling_Formal (Formal) | |
812 | and then Is_Entity_Name (Actual) | |
813 | and then Is_Tagged_Type (Etype (Actual)) | |
814 | then | |
815 | Static_Tag := Actual; | |
82c80734 RD |
816 | end if; |
817 | ||
996ae0b0 | 818 | Next_Actual (Actual); |
82c80734 | 819 | Next_Formal (Formal); |
996ae0b0 RK |
820 | end loop; |
821 | ||
550f4135 AC |
822 | -- If the call doesn't have a controlling actual but does have an |
823 | -- indeterminate actual that requires dispatching treatment, then an | |
03459f40 | 824 | -- object is needed that will serve as the controlling argument for |
ec6cfc5d AC |
825 | -- a dispatching call on the indeterminate actual. This can occur |
826 | -- in the unusual situation of a default actual given by a tag- | |
827 | -- indeterminate call and where the type of the call is an ancestor | |
828 | -- of the type associated with a containing call to an inherited | |
829 | -- operation (see AI-239). | |
550f4135 | 830 | |
03459f40 AC |
831 | -- Rather than create an object of the tagged type, which would |
832 | -- be problematic for various reasons (default initialization, | |
833 | -- discriminants), the tag of the containing call's associated | |
834 | -- tagged type is directly used to control the dispatching. | |
82c80734 | 835 | |
3bcd6930 | 836 | if No (Control) |
82c80734 | 837 | and then Indeterm_Ancestor_Call |
d215a13c | 838 | and then No (Static_Tag) |
82c80734 RD |
839 | then |
840 | Control := | |
841 | Make_Attribute_Reference (Loc, | |
842 | Prefix => New_Occurrence_Of (Indeterm_Ctrl_Type, Loc), | |
843 | Attribute_Name => Name_Tag); | |
d215a13c | 844 | |
82c80734 RD |
845 | Analyze (Control); |
846 | end if; | |
847 | ||
996ae0b0 RK |
848 | if Present (Control) then |
849 | ||
850 | -- Verify that no controlling arguments are statically tagged | |
851 | ||
852 | if Debug_Flag_E then | |
853 | Write_Str ("Found Dispatching call"); | |
854 | Write_Int (Int (N)); | |
855 | Write_Eol; | |
856 | end if; | |
857 | ||
858 | Actual := First_Actual (N); | |
996ae0b0 RK |
859 | while Present (Actual) loop |
860 | if Actual /= Control then | |
861 | ||
862 | if not Is_Controlling_Actual (Actual) then | |
82c80734 | 863 | null; -- Can be anything |
996ae0b0 | 864 | |
fbf5a39b | 865 | elsif Is_Dynamically_Tagged (Actual) then |
82c80734 | 866 | null; -- Valid parameter |
996ae0b0 RK |
867 | |
868 | elsif Is_Tag_Indeterminate (Actual) then | |
869 | ||
550f4135 AC |
870 | -- The tag is inherited from the enclosing call (the node |
871 | -- we are currently analyzing). Explicitly expand the | |
872 | -- actual, since the previous call to Expand (from | |
03459f40 AC |
873 | -- Resolve_Call) had no way of knowing about the |
874 | -- required dispatching. | |
996ae0b0 RK |
875 | |
876 | Propagate_Tag (Control, Actual); | |
877 | ||
878 | else | |
879 | Error_Msg_N | |
880 | ("controlling argument is not dynamically tagged", | |
881 | Actual); | |
882 | return; | |
883 | end if; | |
884 | end if; | |
885 | ||
886 | Next_Actual (Actual); | |
887 | end loop; | |
888 | ||
889 | -- Mark call as a dispatching call | |
890 | ||
891 | Set_Controlling_Argument (N, Control); | |
dee4682a | 892 | Check_Restriction (No_Dispatching_Calls, N); |
996ae0b0 | 893 | |
4f91a255 AC |
894 | -- The dispatching call may need to be converted into a direct |
895 | -- call in certain cases. | |
896 | ||
897 | Check_Direct_Call; | |
898 | ||
20e8cdd7 GD |
899 | -- If there is a statically tagged actual and a tag-indeterminate |
900 | -- call to a function of the ancestor (such as that provided by a | |
901 | -- default), then treat this as a dispatching call and propagate | |
902 | -- the tag to the tag-indeterminate call(s). | |
d215a13c | 903 | |
20e8cdd7 | 904 | elsif Present (Static_Tag) and then Indeterm_Ancestor_Call then |
d215a13c ES |
905 | Control := |
906 | Make_Attribute_Reference (Loc, | |
907 | Prefix => | |
908 | New_Occurrence_Of (Etype (Static_Tag), Loc), | |
909 | Attribute_Name => Name_Tag); | |
910 | ||
911 | Analyze (Control); | |
912 | ||
913 | Actual := First_Actual (N); | |
914 | Formal := First_Formal (Subp_Entity); | |
915 | while Present (Actual) loop | |
916 | if Is_Tag_Indeterminate (Actual) | |
917 | and then Is_Controlling_Formal (Formal) | |
918 | then | |
919 | Propagate_Tag (Control, Actual); | |
920 | end if; | |
921 | ||
922 | Next_Actual (Actual); | |
923 | Next_Formal (Formal); | |
924 | end loop; | |
925 | ||
0d66b596 AC |
926 | Check_Dispatching_Context (N); |
927 | ||
928 | elsif Nkind (N) /= N_Function_Call then | |
d215a13c | 929 | |
82c80734 | 930 | -- The call is not dispatching, so check that there aren't any |
0d66b596 | 931 | -- tag-indeterminate abstract calls left among its actuals. |
996ae0b0 RK |
932 | |
933 | Actual := First_Actual (N); | |
996ae0b0 RK |
934 | while Present (Actual) loop |
935 | if Is_Tag_Indeterminate (Actual) then | |
936 | ||
937 | -- Function call case | |
938 | ||
939 | if Nkind (Original_Node (Actual)) = N_Function_Call then | |
940 | Func := Entity (Name (Original_Node (Actual))); | |
941 | ||
3bcd6930 JM |
942 | -- If the actual is an attribute then it can't be abstract |
943 | -- (the only current case of a tag-indeterminate attribute | |
944 | -- is the stream Input attribute). | |
945 | ||
ccd6f414 | 946 | elsif Nkind (Original_Node (Actual)) = N_Attribute_Reference |
3bcd6930 JM |
947 | then |
948 | Func := Empty; | |
949 | ||
0d66b596 | 950 | -- Ditto if it is an explicit dereference |
167b47d9 | 951 | |
ccd6f414 | 952 | elsif Nkind (Original_Node (Actual)) = N_Explicit_Dereference |
167b47d9 AC |
953 | then |
954 | Func := Empty; | |
955 | ||
996ae0b0 | 956 | -- Only other possibility is a qualified expression whose |
8909e1ed | 957 | -- constituent expression is itself a call. |
996ae0b0 RK |
958 | |
959 | else | |
960 | Func := | |
ccd6f414 | 961 | Entity (Name (Original_Node |
0d66b596 | 962 | (Expression (Original_Node (Actual))))); |
996ae0b0 RK |
963 | end if; |
964 | ||
dee4682a | 965 | if Present (Func) and then Is_Abstract_Subprogram (Func) then |
ed2233dc | 966 | Error_Msg_N |
0d66b596 AC |
967 | ("call to abstract function must be dispatching", |
968 | Actual); | |
996ae0b0 RK |
969 | end if; |
970 | end if; | |
971 | ||
972 | Next_Actual (Actual); | |
973 | end loop; | |
974 | ||
0d66b596 | 975 | Check_Dispatching_Context (N); |
0d66b596 AC |
976 | |
977 | elsif Nkind (Parent (N)) in N_Subexpr then | |
978 | Check_Dispatching_Context (N); | |
979 | ||
980 | elsif Nkind (Parent (N)) = N_Assignment_Statement | |
981 | and then Is_Class_Wide_Type (Etype (Name (Parent (N)))) | |
982 | then | |
983 | return; | |
984 | ||
985 | elsif Is_Abstract_Subprogram (Subp_Entity) then | |
986 | Check_Dispatching_Context (N); | |
987 | return; | |
996ae0b0 RK |
988 | end if; |
989 | ||
14212dc4 GD |
990 | -- If this is a nondispatching call to a nonabstract subprogram |
991 | -- and the subprogram has any Pre'Class or Post'Class aspects with | |
992 | -- nonstatic values, then report an error. This is specified by | |
993 | -- RM 6.1.1(18.2/5) (by AI12-0412). | |
994 | ||
995 | if No (Control) | |
996 | and then not Is_Abstract_Subprogram (Subp_Entity) | |
997 | and then | |
998 | Is_Prim_Of_Abst_Type_With_Nonstatic_CW_Pre_Post (Subp_Entity) | |
999 | then | |
1000 | Error_Msg_N | |
1001 | ("nondispatching call to nonabstract subprogram of " | |
1002 | & "abstract type with nonstatic class-wide " | |
1003 | & "pre/postconditions", | |
1004 | N); | |
1005 | end if; | |
1006 | ||
996ae0b0 RK |
1007 | else |
1008 | -- If dispatching on result, the enclosing call, if any, will | |
1009 | -- determine the controlling argument. Otherwise this is the | |
1010 | -- primitive operation of the root type. | |
1011 | ||
0d66b596 | 1012 | Check_Dispatching_Context (N); |
996ae0b0 RK |
1013 | end if; |
1014 | end Check_Dispatching_Call; | |
1015 | ||
1016 | --------------------------------- | |
1017 | -- Check_Dispatching_Operation -- | |
1018 | --------------------------------- | |
1019 | ||
1020 | procedure Check_Dispatching_Operation (Subp, Old_Subp : Entity_Id) is | |
48c8c473 AC |
1021 | procedure Warn_On_Late_Primitive_After_Private_Extension |
1022 | (Typ : Entity_Id; | |
1023 | Prim : Entity_Id); | |
1024 | -- Prim is a dispatching primitive of the tagged type Typ. Warn on Prim | |
1025 | -- if it is a public primitive defined after some private extension of | |
1026 | -- the tagged type. | |
1027 | ||
1028 | ---------------------------------------------------- | |
1029 | -- Warn_On_Late_Primitive_After_Private_Extension -- | |
1030 | ---------------------------------------------------- | |
1031 | ||
1032 | procedure Warn_On_Late_Primitive_After_Private_Extension | |
1033 | (Typ : Entity_Id; | |
1034 | Prim : Entity_Id) | |
1035 | is | |
1036 | E : Entity_Id; | |
1037 | ||
1038 | begin | |
1039 | if Warn_On_Late_Primitives | |
1040 | and then Comes_From_Source (Prim) | |
1041 | and then Has_Private_Extension (Typ) | |
1042 | and then Is_Package_Or_Generic_Package (Current_Scope) | |
1043 | and then not In_Private_Part (Current_Scope) | |
1044 | then | |
1045 | E := Next_Entity (Typ); | |
1046 | ||
1047 | while E /= Prim loop | |
1048 | if Ekind (E) = E_Record_Type_With_Private | |
1049 | and then Etype (E) = Typ | |
1050 | then | |
1051 | Error_Msg_Name_1 := Chars (Typ); | |
1052 | Error_Msg_Name_2 := Chars (E); | |
1053 | Error_Msg_Sloc := Sloc (E); | |
1054 | Error_Msg_N | |
ec40b86c HK |
1055 | ("?j?primitive of type % defined after private extension " |
1056 | & "% #?", Prim); | |
48c8c473 AC |
1057 | Error_Msg_Name_1 := Chars (Prim); |
1058 | Error_Msg_Name_2 := Chars (E); | |
1059 | Error_Msg_N | |
1060 | ("\spec of % should appear before declaration of type %!", | |
1061 | Prim); | |
1062 | exit; | |
1063 | end if; | |
1064 | ||
1065 | Next_Entity (E); | |
1066 | end loop; | |
1067 | end if; | |
1068 | end Warn_On_Late_Primitive_After_Private_Extension; | |
1069 | ||
1070 | -- Local variables | |
1071 | ||
ea034236 | 1072 | Body_Is_Last_Primitive : Boolean := False; |
54740d7d | 1073 | Has_Dispatching_Parent : Boolean := False; |
ea034236 | 1074 | Ovr_Subp : Entity_Id := Empty; |
54740d7d | 1075 | Tagged_Type : Entity_Id; |
996ae0b0 | 1076 | |
ec40b86c HK |
1077 | -- Start of processing for Check_Dispatching_Operation |
1078 | ||
996ae0b0 | 1079 | begin |
4a08c95c | 1080 | if Ekind (Subp) not in E_Function | E_Procedure then |
54740d7d AC |
1081 | return; |
1082 | ||
1083 | -- The Default_Initial_Condition procedure is not a primitive subprogram | |
1084 | -- even if it relates to a tagged type. This routine is not meant to be | |
1085 | -- inherited or overridden. | |
1086 | ||
1087 | elsif Is_DIC_Procedure (Subp) then | |
1088 | return; | |
1089 | ||
1090 | -- The "partial" and "full" type invariant procedures are not primitive | |
1091 | -- subprograms even if they relate to a tagged type. These routines are | |
1092 | -- not meant to be inherited or overridden. | |
1093 | ||
1094 | elsif Is_Invariant_Procedure (Subp) | |
1095 | or else Is_Partial_Invariant_Procedure (Subp) | |
1096 | then | |
996ae0b0 RK |
1097 | return; |
1098 | end if; | |
1099 | ||
1100 | Set_Is_Dispatching_Operation (Subp, False); | |
07fc65c4 | 1101 | Tagged_Type := Find_Dispatching_Type (Subp); |
996ae0b0 | 1102 | |
bb10b891 | 1103 | -- Ada 2005 (AI-345): Use the corresponding record (if available). |
f0b741b6 | 1104 | -- Required because primitives of concurrent types are attached |
bb10b891 | 1105 | -- to the corresponding record (not to the concurrent type). |
758c442c | 1106 | |
0791fbe9 | 1107 | if Ada_Version >= Ada_2005 |
758c442c GD |
1108 | and then Present (Tagged_Type) |
1109 | and then Is_Concurrent_Type (Tagged_Type) | |
bb10b891 | 1110 | and then Present (Corresponding_Record_Type (Tagged_Type)) |
758c442c GD |
1111 | then |
1112 | Tagged_Type := Corresponding_Record_Type (Tagged_Type); | |
1113 | end if; | |
1114 | ||
ce2b6ba5 JM |
1115 | -- (AI-345): The task body procedure is not a primitive of the tagged |
1116 | -- type | |
1117 | ||
1118 | if Present (Tagged_Type) | |
1119 | and then Is_Concurrent_Record_Type (Tagged_Type) | |
1120 | and then Present (Corresponding_Concurrent_Type (Tagged_Type)) | |
1121 | and then Is_Task_Type (Corresponding_Concurrent_Type (Tagged_Type)) | |
1122 | and then Subp = Get_Task_Body_Procedure | |
1123 | (Corresponding_Concurrent_Type (Tagged_Type)) | |
1124 | then | |
1125 | return; | |
1126 | end if; | |
1127 | ||
996ae0b0 RK |
1128 | -- If Subp is derived from a dispatching operation then it should |
1129 | -- always be treated as dispatching. In this case various checks | |
1130 | -- below will be bypassed. Makes sure that late declarations for | |
1131 | -- inherited private subprograms are treated as dispatching, even | |
1132 | -- if the associated tagged type is already frozen. | |
1133 | ||
fbf5a39b | 1134 | Has_Dispatching_Parent := |
87fd6836 AC |
1135 | Present (Alias (Subp)) |
1136 | and then Is_Dispatching_Operation (Alias (Subp)); | |
996ae0b0 | 1137 | |
07fc65c4 | 1138 | if No (Tagged_Type) then |
67f3c450 HK |
1139 | |
1140 | -- Ada 2005 (AI-251): Check that Subp is not a primitive associated | |
1141 | -- with an abstract interface type unless the interface acts as a | |
1142 | -- parent type in a derivation. If the interface type is a formal | |
1143 | -- type then the operation is not primitive and therefore legal. | |
1144 | ||
1145 | declare | |
1146 | E : Entity_Id; | |
1147 | Typ : Entity_Id; | |
1148 | ||
1149 | begin | |
1150 | E := First_Entity (Subp); | |
1151 | while Present (E) loop | |
76a69663 | 1152 | |
01957849 | 1153 | -- For an access parameter, check designated type |
76a69663 ES |
1154 | |
1155 | if Ekind (Etype (E)) = E_Anonymous_Access_Type then | |
67f3c450 HK |
1156 | Typ := Designated_Type (Etype (E)); |
1157 | else | |
1158 | Typ := Etype (E); | |
1159 | end if; | |
1160 | ||
f9c0d38c | 1161 | if Comes_From_Source (Subp) |
67f3c450 | 1162 | and then Is_Interface (Typ) |
f9c0d38c | 1163 | and then not Is_Class_Wide_Type (Typ) |
67f3c450 HK |
1164 | and then not Is_Derived_Type (Typ) |
1165 | and then not Is_Generic_Type (Typ) | |
8909e1ed | 1166 | and then not In_Instance |
67f3c450 | 1167 | then |
324ac540 | 1168 | Error_Msg_N ("??declaration of& is too late!", Subp); |
ed2233dc | 1169 | Error_Msg_NE -- CODEFIX?? |
ec40b86c HK |
1170 | ("\??spec should appear immediately after declaration of " |
1171 | & "& !", Subp, Typ); | |
67f3c450 HK |
1172 | exit; |
1173 | end if; | |
1174 | ||
1175 | Next_Entity (E); | |
1176 | end loop; | |
1177 | ||
1178 | -- In case of functions check also the result type | |
1179 | ||
1180 | if Ekind (Subp) = E_Function then | |
1181 | if Is_Access_Type (Etype (Subp)) then | |
1182 | Typ := Designated_Type (Etype (Subp)); | |
1183 | else | |
1184 | Typ := Etype (Subp); | |
1185 | end if; | |
1186 | ||
996c8821 RD |
1187 | -- The following should be better commented, especially since |
1188 | -- we just added several new conditions here ??? | |
1189 | ||
d15f9422 | 1190 | if Comes_From_Source (Subp) |
67f3c450 | 1191 | and then Is_Interface (Typ) |
d15f9422 | 1192 | and then not Is_Class_Wide_Type (Typ) |
67f3c450 | 1193 | and then not Is_Derived_Type (Typ) |
d15f9422 AC |
1194 | and then not Is_Generic_Type (Typ) |
1195 | and then not In_Instance | |
67f3c450 | 1196 | then |
324ac540 | 1197 | Error_Msg_N ("??declaration of& is too late!", Subp); |
67f3c450 | 1198 | Error_Msg_NE |
ec40b86c HK |
1199 | ("\??spec should appear immediately after declaration of " |
1200 | & "& !", Subp, Typ); | |
67f3c450 HK |
1201 | end if; |
1202 | end if; | |
1203 | end; | |
1204 | ||
996ae0b0 RK |
1205 | return; |
1206 | ||
1207 | -- The subprograms build internally after the freezing point (such as | |
26a43556 AC |
1208 | -- init procs, interface thunks, type support subprograms, and Offset |
1209 | -- to top functions for accessing interface components in variable | |
1210 | -- size tagged types) are not primitives. | |
996ae0b0 | 1211 | |
07fc65c4 | 1212 | elsif Is_Frozen (Tagged_Type) |
996ae0b0 RK |
1213 | and then not Comes_From_Source (Subp) |
1214 | and then not Has_Dispatching_Parent | |
1215 | then | |
74853971 | 1216 | -- Complete decoration of internally built subprograms that override |
26a43556 AC |
1217 | -- a dispatching primitive. These entities correspond with the |
1218 | -- following cases: | |
1219 | ||
1220 | -- 1. Ada 2005 (AI-391): Wrapper functions built by the expander | |
1221 | -- to override functions of nonabstract null extensions. These | |
1222 | -- primitives were added to the list of primitives of the tagged | |
1223 | -- type by Make_Controlling_Function_Wrappers. However, attribute | |
1224 | -- Is_Dispatching_Operation must be set to true. | |
1225 | ||
0052da20 JM |
1226 | -- 2. Ada 2005 (AI-251): Wrapper procedures of null interface |
1227 | -- primitives. | |
1228 | ||
1229 | -- 3. Subprograms associated with stream attributes (built by | |
b4b023c4 | 1230 | -- New_Stream_Subprogram) or with the Put_Image attribute. |
26a43556 | 1231 | |
31fde973 | 1232 | -- 4. Wrappers built for inherited operations with inherited class- |
a187206c AC |
1233 | -- wide conditions, where the conditions include calls to other |
1234 | -- overridden primitives. The wrappers include checks on these | |
1235 | -- modified conditions. (AI12-113). | |
1236 | ||
31fde973 | 1237 | -- 5. Declarations built for subprograms without separate specs that |
bab15911 YM |
1238 | -- are eligible for inlining in GNATprove (inside |
1239 | -- Sem_Ch6.Analyze_Subprogram_Body_Helper). | |
1240 | ||
26a43556 | 1241 | if Present (Old_Subp) |
038140ed | 1242 | and then Present (Overridden_Operation (Subp)) |
26a43556 AC |
1243 | and then Is_Dispatching_Operation (Old_Subp) |
1244 | then | |
1245 | pragma Assert | |
df3e68b1 | 1246 | ((Ekind (Subp) = E_Function |
2c1b72d7 AC |
1247 | and then Is_Dispatching_Operation (Old_Subp) |
1248 | and then Is_Null_Extension (Base_Type (Etype (Subp)))) | |
a187206c | 1249 | |
df3e68b1 HK |
1250 | or else |
1251 | (Ekind (Subp) = E_Procedure | |
2c1b72d7 AC |
1252 | and then Is_Dispatching_Operation (Old_Subp) |
1253 | and then Present (Alias (Old_Subp)) | |
1254 | and then Is_Null_Interface_Primitive | |
0052da20 | 1255 | (Ultimate_Alias (Old_Subp))) |
a187206c | 1256 | |
df3e68b1 | 1257 | or else Get_TSS_Name (Subp) = TSS_Stream_Read |
a187206c | 1258 | or else Get_TSS_Name (Subp) = TSS_Stream_Write |
b4b023c4 | 1259 | or else Get_TSS_Name (Subp) = TSS_Put_Image |
a187206c | 1260 | |
c37c13e1 JM |
1261 | or else |
1262 | (Is_Wrapper (Subp) | |
1263 | and then Present (LSP_Subprogram (Subp))) | |
bab15911 YM |
1264 | |
1265 | or else GNATprove_Mode); | |
26a43556 | 1266 | |
0052da20 JM |
1267 | Check_Controlling_Formals (Tagged_Type, Subp); |
1268 | Override_Dispatching_Operation (Tagged_Type, Old_Subp, Subp); | |
26a43556 AC |
1269 | Set_Is_Dispatching_Operation (Subp); |
1270 | end if; | |
1271 | ||
996ae0b0 RK |
1272 | return; |
1273 | ||
1274 | -- The operation may be a child unit, whose scope is the defining | |
1275 | -- package, but which is not a primitive operation of the type. | |
1276 | ||
1277 | elsif Is_Child_Unit (Subp) then | |
1278 | return; | |
1279 | ||
1280 | -- If the subprogram is not defined in a package spec, the only case | |
1281 | -- where it can be a dispatching op is when it overrides an operation | |
1282 | -- before the freezing point of the type. | |
1283 | ||
5dcc05e6 JM |
1284 | elsif ((not Is_Package_Or_Generic_Package (Scope (Subp))) |
1285 | or else In_Package_Body (Scope (Subp))) | |
996ae0b0 RK |
1286 | and then not Has_Dispatching_Parent |
1287 | then | |
1288 | if not Comes_From_Source (Subp) | |
07fc65c4 | 1289 | or else (Present (Old_Subp) and then not Is_Frozen (Tagged_Type)) |
996ae0b0 RK |
1290 | then |
1291 | null; | |
1292 | ||
1293 | -- If the type is already frozen, the overriding is not allowed | |
d7f94401 AC |
1294 | -- except when Old_Subp is not a dispatching operation (which can |
1295 | -- occur when Old_Subp was inherited by an untagged type). However, | |
0e41a941 | 1296 | -- a body with no previous spec freezes the type *after* its |
d7f94401 AC |
1297 | -- declaration, and therefore is a legal overriding (unless the type |
1298 | -- has already been frozen). Only the first such body is legal. | |
996ae0b0 RK |
1299 | |
1300 | elsif Present (Old_Subp) | |
1301 | and then Is_Dispatching_Operation (Old_Subp) | |
1302 | then | |
758c442c GD |
1303 | if Comes_From_Source (Subp) |
1304 | and then | |
1305 | (Nkind (Unit_Declaration_Node (Subp)) = N_Subprogram_Body | |
1306 | or else Nkind (Unit_Declaration_Node (Subp)) in N_Body_Stub) | |
996ae0b0 RK |
1307 | then |
1308 | declare | |
1309 | Subp_Body : constant Node_Id := Unit_Declaration_Node (Subp); | |
0e41a941 | 1310 | Decl_Item : Node_Id; |
996ae0b0 RK |
1311 | |
1312 | begin | |
03459f40 AC |
1313 | -- ??? The checks here for whether the type has been frozen |
1314 | -- prior to the new body are not complete. It's not simple | |
1315 | -- to check frozenness at this point since the body has | |
1316 | -- already caused the type to be prematurely frozen in | |
1317 | -- Analyze_Declarations, but we're forced to recheck this | |
1318 | -- here because of the odd rule interpretation that allows | |
1319 | -- the overriding if the type wasn't frozen prior to the | |
1320 | -- body. The freezing action should probably be delayed | |
1321 | -- until after the spec is seen, but that's a tricky | |
1322 | -- change to the delicate freezing code. | |
996ae0b0 | 1323 | |
f559e62f AC |
1324 | -- Look at each declaration following the type up until the |
1325 | -- new subprogram body. If any of the declarations is a body | |
1326 | -- then the type has been frozen already so the overriding | |
1327 | -- primitive is illegal. | |
996ae0b0 | 1328 | |
0e41a941 | 1329 | Decl_Item := Next (Parent (Tagged_Type)); |
996ae0b0 RK |
1330 | while Present (Decl_Item) |
1331 | and then (Decl_Item /= Subp_Body) | |
1332 | loop | |
1333 | if Comes_From_Source (Decl_Item) | |
1334 | and then (Nkind (Decl_Item) in N_Proper_Body | |
1335 | or else Nkind (Decl_Item) in N_Body_Stub) | |
1336 | then | |
1337 | Error_Msg_N ("overriding of& is too late!", Subp); | |
1338 | Error_Msg_N | |
1339 | ("\spec should appear immediately after the type!", | |
1340 | Subp); | |
1341 | exit; | |
1342 | end if; | |
1343 | ||
1344 | Next (Decl_Item); | |
1345 | end loop; | |
1346 | ||
1347 | -- If the subprogram doesn't follow in the list of | |
f559e62f AC |
1348 | -- declarations including the type then the type has |
1349 | -- definitely been frozen already and the body is illegal. | |
996ae0b0 | 1350 | |
3bcd6930 | 1351 | if No (Decl_Item) then |
996ae0b0 RK |
1352 | Error_Msg_N ("overriding of& is too late!", Subp); |
1353 | Error_Msg_N | |
1354 | ("\spec should appear immediately after the type!", | |
1355 | Subp); | |
1356 | ||
1357 | elsif Is_Frozen (Subp) then | |
1358 | ||
fbf5a39b | 1359 | -- The subprogram body declares a primitive operation. |
03459f40 | 1360 | -- If the subprogram is already frozen, we must update |
996ae0b0 RK |
1361 | -- its dispatching information explicitly here. The |
1362 | -- information is taken from the overridden subprogram. | |
f7d5442e ES |
1363 | -- We must also generate a cross-reference entry because |
1364 | -- references to other primitives were already created | |
1365 | -- when type was frozen. | |
996ae0b0 RK |
1366 | |
1367 | Body_Is_Last_Primitive := True; | |
1368 | ||
1369 | if Present (DTC_Entity (Old_Subp)) then | |
1370 | Set_DTC_Entity (Subp, DTC_Entity (Old_Subp)); | |
024d33d8 | 1371 | Set_DT_Position_Value (Subp, DT_Position (Old_Subp)); |
3bcd6930 JM |
1372 | |
1373 | if not Restriction_Active (No_Dispatching_Calls) then | |
6e818918 JM |
1374 | if Building_Static_DT (Tagged_Type) then |
1375 | ||
1376 | -- If the static dispatch table has not been | |
1377 | -- built then there is nothing else to do now; | |
1378 | -- otherwise we notify that we cannot build the | |
1379 | -- static dispatch table. | |
1380 | ||
1381 | if Has_Dispatch_Table (Tagged_Type) then | |
1382 | Error_Msg_N | |
a90bd866 RD |
1383 | ("overriding of& is too late for building " |
1384 | & " static dispatch tables!", Subp); | |
6e818918 | 1385 | Error_Msg_N |
a90bd866 RD |
1386 | ("\spec should appear immediately after " |
1387 | & "the type!", Subp); | |
6e818918 JM |
1388 | end if; |
1389 | ||
f46faa08 AC |
1390 | -- No code required to register primitives in VM |
1391 | -- targets | |
1392 | ||
535a8637 | 1393 | elsif not Tagged_Type_Expansion then |
f46faa08 AC |
1394 | null; |
1395 | ||
6e818918 | 1396 | else |
991395ab AC |
1397 | Insert_Actions_After (Subp_Body, |
1398 | Register_Primitive (Sloc (Subp_Body), | |
1399 | Prim => Subp)); | |
6e818918 | 1400 | end if; |
f7d5442e | 1401 | |
4fc26524 | 1402 | -- Indicate that this is an overriding operation, |
308e6f3a | 1403 | -- and replace the overridden entry in the list of |
4fc26524 AC |
1404 | -- primitive operations, which is used for xref |
1405 | -- generation subsequently. | |
1406 | ||
1407 | Generate_Reference (Tagged_Type, Subp, 'P', False); | |
1408 | Override_Dispatching_Operation | |
1409 | (Tagged_Type, Old_Subp, Subp); | |
3bcd6930 | 1410 | end if; |
996ae0b0 RK |
1411 | end if; |
1412 | end if; | |
1413 | end; | |
1414 | ||
1415 | else | |
1416 | Error_Msg_N ("overriding of& is too late!", Subp); | |
1417 | Error_Msg_N | |
1418 | ("\subprogram spec should appear immediately after the type!", | |
1419 | Subp); | |
1420 | end if; | |
1421 | ||
8909e1ed | 1422 | -- If the type is not frozen yet and we are not in the overriding |
996ae0b0 | 1423 | -- case it looks suspiciously like an attempt to define a primitive |
f559e62f | 1424 | -- operation, which requires the declaration to be in a package spec |
21a5b575 | 1425 | -- (3.2.3(6)). Only report cases where the type and subprogram are |
9c870c90 AC |
1426 | -- in the same declaration list (by checking the enclosing parent |
1427 | -- declarations), to avoid spurious warnings on subprograms in | |
03459f40 AC |
1428 | -- instance bodies when the type is declared in the instance spec |
1429 | -- but hasn't been frozen by the instance body. | |
21a5b575 AC |
1430 | |
1431 | elsif not Is_Frozen (Tagged_Type) | |
9c870c90 | 1432 | and then In_Same_List (Parent (Tagged_Type), Parent (Parent (Subp))) |
21a5b575 | 1433 | then |
996ae0b0 | 1434 | Error_Msg_N |
324ac540 | 1435 | ("??not dispatching (must be defined in a package spec)", Subp); |
996ae0b0 RK |
1436 | return; |
1437 | ||
1438 | -- When the type is frozen, it is legitimate to define a new | |
1439 | -- non-primitive operation. | |
1440 | ||
1441 | else | |
1442 | return; | |
1443 | end if; | |
1444 | ||
1445 | -- Now, we are sure that the scope is a package spec. If the subprogram | |
8909e1ed | 1446 | -- is declared after the freezing point of the type that's an error |
996ae0b0 | 1447 | |
07fc65c4 | 1448 | elsif Is_Frozen (Tagged_Type) and then not Has_Dispatching_Parent then |
996ae0b0 RK |
1449 | Error_Msg_N ("this primitive operation is declared too late", Subp); |
1450 | Error_Msg_NE | |
324ac540 | 1451 | ("??no primitive operations for& after this line", |
07fc65c4 GB |
1452 | Freeze_Node (Tagged_Type), |
1453 | Tagged_Type); | |
996ae0b0 RK |
1454 | return; |
1455 | end if; | |
1456 | ||
07fc65c4 | 1457 | Check_Controlling_Formals (Tagged_Type, Subp); |
996ae0b0 | 1458 | |
ea034236 AC |
1459 | Ovr_Subp := Old_Subp; |
1460 | ||
1461 | -- [Ada 2012:AI-0125]: Search for inherited hidden primitive that may be | |
0812b84e AC |
1462 | -- overridden by Subp. This only applies to source subprograms, and |
1463 | -- their declaration must carry an explicit overriding indicator. | |
ea034236 AC |
1464 | |
1465 | if No (Ovr_Subp) | |
1466 | and then Ada_Version >= Ada_2012 | |
0812b84e AC |
1467 | and then Comes_From_Source (Subp) |
1468 | and then | |
1469 | Nkind (Unit_Declaration_Node (Subp)) = N_Subprogram_Declaration | |
ea034236 AC |
1470 | then |
1471 | Ovr_Subp := Find_Hidden_Overridden_Primitive (Subp); | |
0812b84e AC |
1472 | |
1473 | -- Verify that the proper overriding indicator has been supplied. | |
1474 | ||
1475 | if Present (Ovr_Subp) | |
1476 | and then | |
1477 | not Must_Override (Specification (Unit_Declaration_Node (Subp))) | |
1478 | then | |
1479 | Error_Msg_NE ("missing overriding indicator for&", Subp, Subp); | |
1480 | end if; | |
ea034236 AC |
1481 | end if; |
1482 | ||
996ae0b0 RK |
1483 | -- Now it should be a correct primitive operation, put it in the list |
1484 | ||
ea034236 | 1485 | if Present (Ovr_Subp) then |
ce2b6ba5 | 1486 | |
550f4135 AC |
1487 | -- If the type has interfaces we complete this check after we set |
1488 | -- attribute Is_Dispatching_Operation. | |
ce2b6ba5 | 1489 | |
ea034236 | 1490 | Check_Subtype_Conformant (Subp, Ovr_Subp); |
6e818918 | 1491 | |
7b4ebba5 AC |
1492 | -- A primitive operation with the name of a primitive controlled |
1493 | -- operation does not override a non-visible overriding controlled | |
1494 | -- operation, i.e. one declared in a private part when the full | |
1495 | -- view of a type is controlled. Conversely, it will override a | |
1496 | -- visible operation that may be declared in a partial view when | |
1497 | -- the full view is controlled. | |
1498 | ||
4a08c95c | 1499 | if Chars (Subp) in Name_Initialize | Name_Adjust | Name_Finalize |
5950a3ac AC |
1500 | and then Is_Controlled (Tagged_Type) |
1501 | and then not Is_Visibly_Controlled (Tagged_Type) | |
7b4ebba5 | 1502 | and then not Is_Inherited_Public_Operation (Ovr_Subp) |
5950a3ac | 1503 | then |
038140ed | 1504 | Set_Overridden_Operation (Subp, Empty); |
b8dfbe1e | 1505 | |
fd0d899b AC |
1506 | -- If the subprogram specification carries an overriding |
1507 | -- indicator, no need for the warning: it is either redundant, | |
1508 | -- or else an error will be reported. | |
1509 | ||
1510 | if Nkind (Parent (Subp)) = N_Procedure_Specification | |
1511 | and then | |
1512 | (Must_Override (Parent (Subp)) | |
1513 | or else Must_Not_Override (Parent (Subp))) | |
1514 | then | |
1515 | null; | |
b8dfbe1e AC |
1516 | |
1517 | -- Here we need the warning | |
1518 | ||
fd0d899b AC |
1519 | else |
1520 | Error_Msg_NE | |
324ac540 | 1521 | ("operation does not override inherited&??", Subp, Subp); |
fd0d899b | 1522 | end if; |
b8dfbe1e | 1523 | |
5950a3ac | 1524 | else |
ea034236 | 1525 | Override_Dispatching_Operation (Tagged_Type, Ovr_Subp, Subp); |
67f3c450 HK |
1526 | |
1527 | -- Ada 2005 (AI-251): In case of late overriding of a primitive | |
1528 | -- that covers abstract interface subprograms we must register it | |
1529 | -- in all the secondary dispatch tables associated with abstract | |
36b8f95f AC |
1530 | -- interfaces. We do this now only if not building static tables, |
1531 | -- nor when the expander is inactive (we avoid trying to register | |
1532 | -- primitives in semantics-only mode, since the type may not have | |
1533 | -- an associated dispatch table). Otherwise the patch code is | |
1534 | -- emitted after those tables are built, to prevent access before | |
1535 | -- elaboration in gigi. | |
1536 | ||
4460a9bc | 1537 | if Body_Is_Last_Primitive and then Expander_Active then |
67f3c450 HK |
1538 | declare |
1539 | Subp_Body : constant Node_Id := Unit_Declaration_Node (Subp); | |
1540 | Elmt : Elmt_Id; | |
1541 | Prim : Node_Id; | |
1542 | ||
1543 | begin | |
1544 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); | |
1545 | while Present (Elmt) loop | |
1546 | Prim := Node (Elmt); | |
1547 | ||
f46faa08 AC |
1548 | -- No code required to register primitives in VM targets |
1549 | ||
67f3c450 | 1550 | if Present (Alias (Prim)) |
ce2b6ba5 | 1551 | and then Present (Interface_Alias (Prim)) |
67f3c450 | 1552 | and then Alias (Prim) = Subp |
991395ab | 1553 | and then not Building_Static_DT (Tagged_Type) |
535a8637 | 1554 | and then Tagged_Type_Expansion |
67f3c450 | 1555 | then |
991395ab AC |
1556 | Insert_Actions_After (Subp_Body, |
1557 | Register_Primitive (Sloc (Subp_Body), Prim => Prim)); | |
67f3c450 HK |
1558 | end if; |
1559 | ||
1560 | Next_Elmt (Elmt); | |
1561 | end loop; | |
1562 | ||
8909e1ed | 1563 | -- Redisplay the contents of the updated dispatch table |
67f3c450 HK |
1564 | |
1565 | if Debug_Flag_ZZ then | |
1566 | Write_Str ("Late overriding: "); | |
1567 | Write_DT (Tagged_Type); | |
1568 | end if; | |
1569 | end; | |
1570 | end if; | |
5950a3ac | 1571 | end if; |
3bcd6930 JM |
1572 | |
1573 | -- If no old subprogram, then we add this as a dispatching operation, | |
1574 | -- but we avoid doing this if an error was posted, to prevent annoying | |
1575 | -- cascaded errors. | |
1576 | ||
1577 | elsif not Error_Posted (Subp) then | |
07fc65c4 | 1578 | Add_Dispatching_Operation (Tagged_Type, Subp); |
996ae0b0 RK |
1579 | end if; |
1580 | ||
1581 | Set_Is_Dispatching_Operation (Subp, True); | |
1582 | ||
ce2b6ba5 JM |
1583 | -- Ada 2005 (AI-251): If the type implements interfaces we must check |
1584 | -- subtype conformance against all the interfaces covered by this | |
1585 | -- primitive. | |
1586 | ||
ea034236 | 1587 | if Present (Ovr_Subp) |
ce2b6ba5 JM |
1588 | and then Has_Interfaces (Tagged_Type) |
1589 | then | |
1590 | declare | |
1591 | Ifaces_List : Elist_Id; | |
1592 | Iface_Elmt : Elmt_Id; | |
1593 | Iface_Prim_Elmt : Elmt_Id; | |
1594 | Iface_Prim : Entity_Id; | |
1595 | Ret_Typ : Entity_Id; | |
1596 | ||
1597 | begin | |
1598 | Collect_Interfaces (Tagged_Type, Ifaces_List); | |
1599 | ||
1600 | Iface_Elmt := First_Elmt (Ifaces_List); | |
1601 | while Present (Iface_Elmt) loop | |
1602 | if not Is_Ancestor (Node (Iface_Elmt), Tagged_Type) then | |
1603 | Iface_Prim_Elmt := | |
1604 | First_Elmt (Primitive_Operations (Node (Iface_Elmt))); | |
1605 | while Present (Iface_Prim_Elmt) loop | |
1606 | Iface_Prim := Node (Iface_Prim_Elmt); | |
1607 | ||
1608 | if Is_Interface_Conformant | |
1609 | (Tagged_Type, Iface_Prim, Subp) | |
1610 | then | |
1611 | -- Handle procedures, functions whose return type | |
1612 | -- matches, or functions not returning interfaces | |
1613 | ||
1614 | if Ekind (Subp) = E_Procedure | |
1615 | or else Etype (Iface_Prim) = Etype (Subp) | |
1616 | or else not Is_Interface (Etype (Iface_Prim)) | |
1617 | then | |
1618 | Check_Subtype_Conformant | |
1619 | (New_Id => Subp, | |
1620 | Old_Id => Iface_Prim, | |
1621 | Err_Loc => Subp, | |
1622 | Skip_Controlling_Formals => True); | |
1623 | ||
1624 | -- Handle functions returning interfaces | |
1625 | ||
1626 | elsif Implements_Interface | |
1627 | (Etype (Subp), Etype (Iface_Prim)) | |
1628 | then | |
1629 | -- Temporarily force both entities to return the | |
1630 | -- same type. Required because Subtype_Conformant | |
1631 | -- does not handle this case. | |
1632 | ||
1633 | Ret_Typ := Etype (Iface_Prim); | |
1634 | Set_Etype (Iface_Prim, Etype (Subp)); | |
1635 | ||
1636 | Check_Subtype_Conformant | |
1637 | (New_Id => Subp, | |
1638 | Old_Id => Iface_Prim, | |
1639 | Err_Loc => Subp, | |
1640 | Skip_Controlling_Formals => True); | |
1641 | ||
1642 | Set_Etype (Iface_Prim, Ret_Typ); | |
1643 | end if; | |
1644 | end if; | |
1645 | ||
1646 | Next_Elmt (Iface_Prim_Elmt); | |
1647 | end loop; | |
1648 | end if; | |
1649 | ||
1650 | Next_Elmt (Iface_Elmt); | |
1651 | end loop; | |
1652 | end; | |
1653 | end if; | |
1654 | ||
996ae0b0 | 1655 | if not Body_Is_Last_Primitive then |
024d33d8 | 1656 | Set_DT_Position_Value (Subp, No_Uint); |
996ae0b0 | 1657 | |
07fc65c4 | 1658 | elsif Has_Controlled_Component (Tagged_Type) |
4a08c95c AC |
1659 | and then Chars (Subp) in Name_Initialize |
1660 | | Name_Adjust | |
1661 | | Name_Finalize | |
1662 | | Name_Finalize_Address | |
07fc65c4 GB |
1663 | then |
1664 | declare | |
fbf5a39b | 1665 | F_Node : constant Node_Id := Freeze_Node (Tagged_Type); |
07fc65c4 GB |
1666 | Decl : Node_Id; |
1667 | Old_P : Entity_Id; | |
1668 | Old_Bod : Node_Id; | |
1669 | Old_Spec : Entity_Id; | |
1670 | ||
df3e68b1 | 1671 | C_Names : constant array (1 .. 4) of Name_Id := |
07fc65c4 GB |
1672 | (Name_Initialize, |
1673 | Name_Adjust, | |
df3e68b1 HK |
1674 | Name_Finalize, |
1675 | Name_Finalize_Address); | |
07fc65c4 | 1676 | |
df3e68b1 | 1677 | D_Names : constant array (1 .. 4) of TSS_Name_Type := |
fbf5a39b AC |
1678 | (TSS_Deep_Initialize, |
1679 | TSS_Deep_Adjust, | |
df3e68b1 HK |
1680 | TSS_Deep_Finalize, |
1681 | TSS_Finalize_Address); | |
07fc65c4 GB |
1682 | |
1683 | begin | |
0e41a941 AC |
1684 | -- Remove previous controlled function which was constructed and |
1685 | -- analyzed when the type was frozen. This requires removing the | |
1686 | -- body of the redefined primitive, as well as its specification | |
1687 | -- if needed (there is no spec created for Deep_Initialize, see | |
1688 | -- exp_ch3.adb). We must also dismantle the exception information | |
1689 | -- that may have been generated for it when front end zero-cost | |
1690 | -- tables are enabled. | |
07fc65c4 GB |
1691 | |
1692 | for J in D_Names'Range loop | |
1693 | Old_P := TSS (Tagged_Type, D_Names (J)); | |
1694 | ||
1695 | if Present (Old_P) | |
1696 | and then Chars (Subp) = C_Names (J) | |
1697 | then | |
1698 | Old_Bod := Unit_Declaration_Node (Old_P); | |
1699 | Remove (Old_Bod); | |
1700 | Set_Is_Eliminated (Old_P); | |
1701 | Set_Scope (Old_P, Scope (Current_Scope)); | |
1702 | ||
1703 | if Nkind (Old_Bod) = N_Subprogram_Body | |
1704 | and then Present (Corresponding_Spec (Old_Bod)) | |
1705 | then | |
1706 | Old_Spec := Corresponding_Spec (Old_Bod); | |
1707 | Set_Has_Completion (Old_Spec, False); | |
07fc65c4 | 1708 | end if; |
07fc65c4 GB |
1709 | end if; |
1710 | end loop; | |
1711 | ||
1712 | Build_Late_Proc (Tagged_Type, Chars (Subp)); | |
1713 | ||
0e41a941 AC |
1714 | -- The new operation is added to the actions of the freeze node |
1715 | -- for the type, but this node has already been analyzed, so we | |
1716 | -- must retrieve and analyze explicitly the new body. | |
07fc65c4 GB |
1717 | |
1718 | if Present (F_Node) | |
1719 | and then Present (Actions (F_Node)) | |
1720 | then | |
1721 | Decl := Last (Actions (F_Node)); | |
1722 | Analyze (Decl); | |
1723 | end if; | |
1724 | end; | |
1725 | end if; | |
48c8c473 | 1726 | |
8afbdb8a JM |
1727 | -- AI12-0279: If the Yield aspect is specified for a dispatching |
1728 | -- subprogram that inherits the aspect, the specified value shall | |
1729 | -- be confirming. | |
1730 | ||
1731 | if Is_Dispatching_Operation (Subp) | |
1732 | and then Is_Primitive_Wrapper (Subp) | |
1733 | and then Present (Wrapped_Entity (Subp)) | |
1734 | and then Comes_From_Source (Wrapped_Entity (Subp)) | |
1735 | and then Present (Overridden_Operation (Subp)) | |
1736 | and then Has_Yield_Aspect (Overridden_Operation (Subp)) | |
1737 | /= Has_Yield_Aspect (Wrapped_Entity (Subp)) | |
1738 | then | |
1739 | declare | |
1740 | W_Ent : constant Entity_Id := Wrapped_Entity (Subp); | |
1741 | W_Decl : constant Node_Id := Parent (W_Ent); | |
1742 | Asp : Node_Id; | |
1743 | ||
1744 | begin | |
1745 | if Present (Aspect_Specifications (W_Decl)) then | |
1746 | Asp := First (Aspect_Specifications (W_Decl)); | |
1747 | while Present (Asp) loop | |
1748 | if Chars (Identifier (Asp)) = Name_Yield then | |
1749 | Error_Msg_Name_1 := Name_Yield; | |
1750 | Error_Msg_N | |
1751 | ("specification of inherited aspect% can only confirm " | |
1752 | & "parent value", Asp); | |
1753 | end if; | |
1754 | ||
1755 | Next (Asp); | |
1756 | end loop; | |
1757 | end if; | |
1758 | ||
1759 | Set_Has_Yield_Aspect (Wrapped_Entity (Subp)); | |
1760 | end; | |
1761 | end if; | |
1762 | ||
48c8c473 AC |
1763 | -- For similarity with record extensions, in Ada 9X the language should |
1764 | -- have disallowed adding visible operations to a tagged type after | |
1765 | -- deriving a private extension from it. Report a warning if this | |
1766 | -- primitive is defined after a private extension of Tagged_Type. | |
1767 | ||
1768 | Warn_On_Late_Primitive_After_Private_Extension (Tagged_Type, Subp); | |
996ae0b0 RK |
1769 | end Check_Dispatching_Operation; |
1770 | ||
1771 | ------------------------------------------ | |
1772 | -- Check_Operation_From_Incomplete_Type -- | |
1773 | ------------------------------------------ | |
1774 | ||
1775 | procedure Check_Operation_From_Incomplete_Type | |
1776 | (Subp : Entity_Id; | |
1777 | Typ : Entity_Id) | |
1778 | is | |
1779 | Full : constant Entity_Id := Full_View (Typ); | |
1780 | Parent_Typ : constant Entity_Id := Etype (Full); | |
1781 | Old_Prim : constant Elist_Id := Primitive_Operations (Parent_Typ); | |
1782 | New_Prim : constant Elist_Id := Primitive_Operations (Full); | |
1783 | Op1, Op2 : Elmt_Id; | |
1784 | Prev : Elmt_Id := No_Elmt; | |
1785 | ||
4637729f AC |
1786 | function Derives_From (Parent_Subp : Entity_Id) return Boolean; |
1787 | -- Check that Subp has profile of an operation derived from Parent_Subp. | |
1788 | -- Subp must have a parameter or result type that is Typ or an access | |
1789 | -- parameter or access result type that designates Typ. | |
996ae0b0 RK |
1790 | |
1791 | ------------------ | |
1792 | -- Derives_From -- | |
1793 | ------------------ | |
1794 | ||
4637729f | 1795 | function Derives_From (Parent_Subp : Entity_Id) return Boolean is |
996ae0b0 RK |
1796 | F1, F2 : Entity_Id; |
1797 | ||
1798 | begin | |
4637729f | 1799 | if Chars (Parent_Subp) /= Chars (Subp) then |
996ae0b0 RK |
1800 | return False; |
1801 | end if; | |
1802 | ||
4637729f AC |
1803 | -- Check that the type of controlling formals is derived from the |
1804 | -- parent subprogram's controlling formal type (or designated type | |
1805 | -- if the formal type is an anonymous access type). | |
1806 | ||
1807 | F1 := First_Formal (Parent_Subp); | |
996ae0b0 | 1808 | F2 := First_Formal (Subp); |
996ae0b0 | 1809 | while Present (F1) and then Present (F2) loop |
996ae0b0 | 1810 | if Ekind (Etype (F1)) = E_Anonymous_Access_Type then |
996ae0b0 RK |
1811 | if Ekind (Etype (F2)) /= E_Anonymous_Access_Type then |
1812 | return False; | |
996ae0b0 RK |
1813 | elsif Designated_Type (Etype (F1)) = Parent_Typ |
1814 | and then Designated_Type (Etype (F2)) /= Full | |
1815 | then | |
1816 | return False; | |
1817 | end if; | |
1818 | ||
1819 | elsif Ekind (Etype (F2)) = E_Anonymous_Access_Type then | |
1820 | return False; | |
1821 | ||
4637729f | 1822 | elsif Etype (F1) = Parent_Typ and then Etype (F2) /= Full then |
996ae0b0 RK |
1823 | return False; |
1824 | end if; | |
1825 | ||
1826 | Next_Formal (F1); | |
1827 | Next_Formal (F2); | |
1828 | end loop; | |
1829 | ||
4637729f AC |
1830 | -- Check that a controlling result type is derived from the parent |
1831 | -- subprogram's result type (or designated type if the result type | |
1832 | -- is an anonymous access type). | |
1833 | ||
1834 | if Ekind (Parent_Subp) = E_Function then | |
1835 | if Ekind (Subp) /= E_Function then | |
1836 | return False; | |
1837 | ||
1838 | elsif Ekind (Etype (Parent_Subp)) = E_Anonymous_Access_Type then | |
1839 | if Ekind (Etype (Subp)) /= E_Anonymous_Access_Type then | |
1840 | return False; | |
1841 | ||
1842 | elsif Designated_Type (Etype (Parent_Subp)) = Parent_Typ | |
1843 | and then Designated_Type (Etype (Subp)) /= Full | |
1844 | then | |
1845 | return False; | |
1846 | end if; | |
1847 | ||
1848 | elsif Ekind (Etype (Subp)) = E_Anonymous_Access_Type then | |
1849 | return False; | |
1850 | ||
1851 | elsif Etype (Parent_Subp) = Parent_Typ | |
1852 | and then Etype (Subp) /= Full | |
1853 | then | |
1854 | return False; | |
1855 | end if; | |
1856 | ||
1857 | elsif Ekind (Subp) = E_Function then | |
1858 | return False; | |
1859 | end if; | |
1860 | ||
996ae0b0 RK |
1861 | return No (F1) and then No (F2); |
1862 | end Derives_From; | |
1863 | ||
1864 | -- Start of processing for Check_Operation_From_Incomplete_Type | |
1865 | ||
1866 | begin | |
1867 | -- The operation may override an inherited one, or may be a new one | |
1868 | -- altogether. The inherited operation will have been hidden by the | |
1869 | -- current one at the point of the type derivation, so it does not | |
1870 | -- appear in the list of primitive operations of the type. We have to | |
1871 | -- find the proper place of insertion in the list of primitive opera- | |
1872 | -- tions by iterating over the list for the parent type. | |
1873 | ||
1874 | Op1 := First_Elmt (Old_Prim); | |
1875 | Op2 := First_Elmt (New_Prim); | |
996ae0b0 | 1876 | while Present (Op1) and then Present (Op2) loop |
996ae0b0 | 1877 | if Derives_From (Node (Op1)) then |
996ae0b0 | 1878 | if No (Prev) then |
ce2b6ba5 | 1879 | |
a90bd866 | 1880 | -- Avoid adding it to the list of primitives if already there |
ce2b6ba5 JM |
1881 | |
1882 | if Node (Op2) /= Subp then | |
1883 | Prepend_Elmt (Subp, New_Prim); | |
1884 | end if; | |
1885 | ||
996ae0b0 RK |
1886 | else |
1887 | Insert_Elmt_After (Subp, Prev); | |
1888 | end if; | |
1889 | ||
1890 | return; | |
1891 | end if; | |
1892 | ||
1893 | Prev := Op2; | |
1894 | Next_Elmt (Op1); | |
1895 | Next_Elmt (Op2); | |
1896 | end loop; | |
1897 | ||
fbf5a39b | 1898 | -- Operation is a new primitive |
996ae0b0 RK |
1899 | |
1900 | Append_Elmt (Subp, New_Prim); | |
996ae0b0 RK |
1901 | end Check_Operation_From_Incomplete_Type; |
1902 | ||
1903 | --------------------------------------- | |
1904 | -- Check_Operation_From_Private_View -- | |
1905 | --------------------------------------- | |
1906 | ||
1907 | procedure Check_Operation_From_Private_View (Subp, Old_Subp : Entity_Id) is | |
1908 | Tagged_Type : Entity_Id; | |
1909 | ||
1910 | begin | |
1911 | if Is_Dispatching_Operation (Alias (Subp)) then | |
1912 | Set_Scope (Subp, Current_Scope); | |
1913 | Tagged_Type := Find_Dispatching_Type (Subp); | |
1914 | ||
01957849 | 1915 | -- Add Old_Subp to primitive operations if not already present |
20e8cdd7 | 1916 | |
996ae0b0 | 1917 | if Present (Tagged_Type) and then Is_Tagged_Type (Tagged_Type) then |
9057bd6a | 1918 | Add_Dispatching_Operation (Tagged_Type, Old_Subp); |
996ae0b0 | 1919 | |
243cae0a AC |
1920 | -- If Old_Subp isn't already marked as dispatching then this is |
1921 | -- the case of an operation of an untagged private type fulfilled | |
1922 | -- by a tagged type that overrides an inherited dispatching | |
1923 | -- operation, so we set the necessary dispatching attributes here. | |
996ae0b0 RK |
1924 | |
1925 | if not Is_Dispatching_Operation (Old_Subp) then | |
fbf5a39b AC |
1926 | |
1927 | -- If the untagged type has no discriminants, and the full | |
243cae0a AC |
1928 | -- view is constrained, there will be a spurious mismatch of |
1929 | -- subtypes on the controlling arguments, because the tagged | |
fbf5a39b AC |
1930 | -- type is the internal base type introduced in the derivation. |
1931 | -- Use the original type to verify conformance, rather than the | |
1932 | -- base type. | |
1933 | ||
1934 | if not Comes_From_Source (Tagged_Type) | |
1935 | and then Has_Discriminants (Tagged_Type) | |
1936 | then | |
1937 | declare | |
1938 | Formal : Entity_Id; | |
0e41a941 | 1939 | |
fbf5a39b AC |
1940 | begin |
1941 | Formal := First_Formal (Old_Subp); | |
1942 | while Present (Formal) loop | |
1943 | if Tagged_Type = Base_Type (Etype (Formal)) then | |
1944 | Tagged_Type := Etype (Formal); | |
1945 | end if; | |
1946 | ||
1947 | Next_Formal (Formal); | |
1948 | end loop; | |
1949 | end; | |
1950 | ||
1951 | if Tagged_Type = Base_Type (Etype (Old_Subp)) then | |
1952 | Tagged_Type := Etype (Old_Subp); | |
1953 | end if; | |
1954 | end if; | |
1955 | ||
996ae0b0 RK |
1956 | Check_Controlling_Formals (Tagged_Type, Old_Subp); |
1957 | Set_Is_Dispatching_Operation (Old_Subp, True); | |
024d33d8 | 1958 | Set_DT_Position_Value (Old_Subp, No_Uint); |
996ae0b0 RK |
1959 | end if; |
1960 | ||
1961 | -- If the old subprogram is an explicit renaming of some other | |
1962 | -- entity, it is not overridden by the inherited subprogram. | |
1963 | -- Otherwise, update its alias and other attributes. | |
1964 | ||
1965 | if Present (Alias (Old_Subp)) | |
0e41a941 AC |
1966 | and then Nkind (Unit_Declaration_Node (Old_Subp)) /= |
1967 | N_Subprogram_Renaming_Declaration | |
996ae0b0 RK |
1968 | then |
1969 | Set_Alias (Old_Subp, Alias (Subp)); | |
1970 | ||
03459f40 AC |
1971 | -- The derived subprogram should inherit the abstractness of |
1972 | -- the parent subprogram (except in the case of a function | |
996ae0b0 | 1973 | -- returning the type). This sets the abstractness properly |
03459f40 AC |
1974 | -- for cases where a private extension may have inherited an |
1975 | -- abstract operation, but the full type is derived from a | |
1976 | -- descendant type and inherits a nonabstract version. | |
996ae0b0 RK |
1977 | |
1978 | if Etype (Subp) /= Tagged_Type then | |
dee4682a JM |
1979 | Set_Is_Abstract_Subprogram |
1980 | (Old_Subp, Is_Abstract_Subprogram (Alias (Subp))); | |
996ae0b0 RK |
1981 | end if; |
1982 | end if; | |
1983 | end if; | |
1984 | end if; | |
1985 | end Check_Operation_From_Private_View; | |
1986 | ||
1987 | -------------------------- | |
1988 | -- Find_Controlling_Arg -- | |
1989 | -------------------------- | |
1990 | ||
1991 | function Find_Controlling_Arg (N : Node_Id) return Node_Id is | |
1992 | Orig_Node : constant Node_Id := Original_Node (N); | |
1993 | Typ : Entity_Id; | |
1994 | ||
1995 | begin | |
1996 | if Nkind (Orig_Node) = N_Qualified_Expression then | |
1997 | return Find_Controlling_Arg (Expression (Orig_Node)); | |
1998 | end if; | |
1999 | ||
ca14fd02 ES |
2000 | -- Dispatching on result case. If expansion is disabled, the node still |
2001 | -- has the structure of a function call. However, if the function name | |
2002 | -- is an operator and the call was given in infix form, the original | |
2003 | -- node has no controlling result and we must examine the current node. | |
2004 | ||
2005 | if Nkind (N) = N_Function_Call | |
2006 | and then Present (Controlling_Argument (N)) | |
2007 | and then Has_Controlling_Result (Entity (Name (N))) | |
2008 | then | |
2009 | return Controlling_Argument (N); | |
2010 | ||
2011 | -- If expansion is enabled, the call may have been transformed into | |
2012 | -- an indirect call, and we need to recover the original node. | |
996ae0b0 | 2013 | |
ca14fd02 | 2014 | elsif Nkind (Orig_Node) = N_Function_Call |
996ae0b0 RK |
2015 | and then Present (Controlling_Argument (Orig_Node)) |
2016 | and then Has_Controlling_Result (Entity (Name (Orig_Node))) | |
2017 | then | |
2018 | return Controlling_Argument (Orig_Node); | |
2019 | ||
5dcab3ca AC |
2020 | -- Type conversions are dynamically tagged if the target type, or its |
2021 | -- designated type, are classwide. An interface conversion expands into | |
2022 | -- a dereference, so test must be performed on the original node. | |
2023 | ||
2024 | elsif Nkind (Orig_Node) = N_Type_Conversion | |
2025 | and then Nkind (N) = N_Explicit_Dereference | |
2026 | and then Is_Controlling_Actual (N) | |
2027 | then | |
2028 | declare | |
2029 | Target_Type : constant Entity_Id := | |
2030 | Entity (Subtype_Mark (Orig_Node)); | |
2031 | ||
2032 | begin | |
2033 | if Is_Class_Wide_Type (Target_Type) then | |
2034 | return N; | |
2035 | ||
2036 | elsif Is_Access_Type (Target_Type) | |
2037 | and then Is_Class_Wide_Type (Designated_Type (Target_Type)) | |
2038 | then | |
2039 | return N; | |
2040 | ||
2041 | else | |
2042 | return Empty; | |
2043 | end if; | |
2044 | end; | |
2045 | ||
996ae0b0 RK |
2046 | -- Normal case |
2047 | ||
fbf5a39b AC |
2048 | elsif Is_Controlling_Actual (N) |
2049 | or else | |
2050 | (Nkind (Parent (N)) = N_Qualified_Expression | |
2051 | and then Is_Controlling_Actual (Parent (N))) | |
2052 | then | |
996ae0b0 RK |
2053 | Typ := Etype (N); |
2054 | ||
2055 | if Is_Access_Type (Typ) then | |
0e41a941 AC |
2056 | |
2057 | -- In the case of an Access attribute, use the type of the prefix, | |
2058 | -- since in the case of an actual for an access parameter, the | |
2059 | -- attribute's type may be of a specific designated type, even | |
2060 | -- though the prefix type is class-wide. | |
996ae0b0 RK |
2061 | |
2062 | if Nkind (N) = N_Attribute_Reference then | |
2063 | Typ := Etype (Prefix (N)); | |
07fc65c4 | 2064 | |
0e41a941 AC |
2065 | -- An allocator is dispatching if the type of qualified expression |
2066 | -- is class_wide, in which case this is the controlling type. | |
07fc65c4 GB |
2067 | |
2068 | elsif Nkind (Orig_Node) = N_Allocator | |
2069 | and then Nkind (Expression (Orig_Node)) = N_Qualified_Expression | |
2070 | then | |
2071 | Typ := Etype (Expression (Orig_Node)); | |
996ae0b0 RK |
2072 | else |
2073 | Typ := Designated_Type (Typ); | |
2074 | end if; | |
2075 | end if; | |
2076 | ||
fbf5a39b AC |
2077 | if Is_Class_Wide_Type (Typ) |
2078 | or else | |
2079 | (Nkind (Parent (N)) = N_Qualified_Expression | |
2080 | and then Is_Access_Type (Etype (N)) | |
2081 | and then Is_Class_Wide_Type (Designated_Type (Etype (N)))) | |
2082 | then | |
996ae0b0 RK |
2083 | return N; |
2084 | end if; | |
2085 | end if; | |
2086 | ||
2087 | return Empty; | |
2088 | end Find_Controlling_Arg; | |
2089 | ||
2090 | --------------------------- | |
2091 | -- Find_Dispatching_Type -- | |
2092 | --------------------------- | |
2093 | ||
2094 | function Find_Dispatching_Type (Subp : Entity_Id) return Entity_Id is | |
ee9aa7b6 | 2095 | A_Formal : Entity_Id; |
996ae0b0 RK |
2096 | Formal : Entity_Id; |
2097 | Ctrl_Type : Entity_Id; | |
2098 | ||
2099 | begin | |
4a08c95c | 2100 | if Ekind (Subp) in E_Function | E_Procedure |
22a83cea AC |
2101 | and then Present (DTC_Entity (Subp)) |
2102 | then | |
996ae0b0 RK |
2103 | return Scope (DTC_Entity (Subp)); |
2104 | ||
ee9aa7b6 AC |
2105 | -- For subprograms internally generated by derivations of tagged types |
2106 | -- use the alias subprogram as a reference to locate the dispatching | |
e1b871e9 | 2107 | -- type of Subp. |
ee9aa7b6 AC |
2108 | |
2109 | elsif not Comes_From_Source (Subp) | |
2110 | and then Present (Alias (Subp)) | |
2111 | and then Is_Dispatching_Operation (Alias (Subp)) | |
2112 | then | |
2113 | if Ekind (Alias (Subp)) = E_Function | |
2114 | and then Has_Controlling_Result (Alias (Subp)) | |
2115 | then | |
2116 | return Check_Controlling_Type (Etype (Subp), Subp); | |
2117 | ||
2118 | else | |
2119 | Formal := First_Formal (Subp); | |
2120 | A_Formal := First_Formal (Alias (Subp)); | |
2121 | while Present (A_Formal) loop | |
2122 | if Is_Controlling_Formal (A_Formal) then | |
2123 | return Check_Controlling_Type (Etype (Formal), Subp); | |
2124 | end if; | |
2125 | ||
2126 | Next_Formal (Formal); | |
2127 | Next_Formal (A_Formal); | |
2128 | end loop; | |
2129 | ||
2130 | pragma Assert (False); | |
2131 | return Empty; | |
2132 | end if; | |
2133 | ||
2134 | -- General case | |
2135 | ||
996ae0b0 RK |
2136 | else |
2137 | Formal := First_Formal (Subp); | |
2138 | while Present (Formal) loop | |
2139 | Ctrl_Type := Check_Controlling_Type (Etype (Formal), Subp); | |
2140 | ||
2141 | if Present (Ctrl_Type) then | |
2142 | return Ctrl_Type; | |
2143 | end if; | |
2144 | ||
2145 | Next_Formal (Formal); | |
2146 | end loop; | |
2147 | ||
ee9aa7b6 | 2148 | -- The subprogram may also be dispatching on result |
996ae0b0 RK |
2149 | |
2150 | if Present (Etype (Subp)) then | |
ee9aa7b6 | 2151 | return Check_Controlling_Type (Etype (Subp), Subp); |
996ae0b0 RK |
2152 | end if; |
2153 | end if; | |
2154 | ||
0e41a941 | 2155 | pragma Assert (not Is_Dispatching_Operation (Subp)); |
996ae0b0 RK |
2156 | return Empty; |
2157 | end Find_Dispatching_Type; | |
2158 | ||
ea034236 AC |
2159 | -------------------------------------- |
2160 | -- Find_Hidden_Overridden_Primitive -- | |
2161 | -------------------------------------- | |
2162 | ||
2163 | function Find_Hidden_Overridden_Primitive (S : Entity_Id) return Entity_Id | |
2164 | is | |
2165 | Tag_Typ : constant Entity_Id := Find_Dispatching_Type (S); | |
2166 | Elmt : Elmt_Id; | |
2167 | Orig_Prim : Entity_Id; | |
2168 | Prim : Entity_Id; | |
2169 | Vis_List : Elist_Id; | |
2170 | ||
2171 | begin | |
57081559 AC |
2172 | -- This Ada 2012 rule applies only for type extensions or private |
2173 | -- extensions, where the parent type is not in a parent unit, and | |
2174 | -- where an operation is never declared but still inherited. | |
ea034236 AC |
2175 | |
2176 | if No (Tag_Typ) | |
2177 | or else not Is_Record_Type (Tag_Typ) | |
2178 | or else Etype (Tag_Typ) = Tag_Typ | |
57081559 | 2179 | or else In_Open_Scopes (Scope (Etype (Tag_Typ))) |
ea034236 AC |
2180 | then |
2181 | return Empty; | |
2182 | end if; | |
2183 | ||
2184 | -- Collect the list of visible ancestor of the tagged type | |
2185 | ||
2186 | Vis_List := Visible_Ancestors (Tag_Typ); | |
2187 | ||
2188 | Elmt := First_Elmt (Primitive_Operations (Tag_Typ)); | |
2189 | while Present (Elmt) loop | |
2190 | Prim := Node (Elmt); | |
2191 | ||
2192 | -- Find an inherited hidden dispatching primitive with the name of S | |
329b9f81 | 2193 | -- and a type-conformant profile. |
ea034236 AC |
2194 | |
2195 | if Present (Alias (Prim)) | |
2196 | and then Is_Hidden (Alias (Prim)) | |
2197 | and then Find_Dispatching_Type (Alias (Prim)) /= Tag_Typ | |
2198 | and then Primitive_Names_Match (S, Prim) | |
2199 | and then Type_Conformant (S, Prim) | |
2200 | then | |
2201 | declare | |
2202 | Vis_Ancestor : Elmt_Id; | |
2203 | Elmt : Elmt_Id; | |
2204 | ||
2205 | begin | |
2206 | -- The original corresponding operation of Prim must be an | |
243cae0a AC |
2207 | -- operation of a visible ancestor of the dispatching type S, |
2208 | -- and the original corresponding operation of S2 must be | |
2209 | -- visible. | |
ea034236 AC |
2210 | |
2211 | Orig_Prim := Original_Corresponding_Operation (Prim); | |
2212 | ||
2213 | if Orig_Prim /= Prim | |
2214 | and then Is_Immediately_Visible (Orig_Prim) | |
2215 | then | |
2216 | Vis_Ancestor := First_Elmt (Vis_List); | |
ea034236 AC |
2217 | while Present (Vis_Ancestor) loop |
2218 | Elmt := | |
2219 | First_Elmt (Primitive_Operations (Node (Vis_Ancestor))); | |
2220 | while Present (Elmt) loop | |
2221 | if Node (Elmt) = Orig_Prim then | |
2222 | Set_Overridden_Operation (S, Prim); | |
07537fe6 JM |
2223 | Set_Is_Ada_2022_Only (S, |
2224 | Is_Ada_2022_Only (Prim)); | |
ea034236 | 2225 | Set_Alias (Prim, Orig_Prim); |
ea034236 AC |
2226 | return Prim; |
2227 | end if; | |
2228 | ||
2229 | Next_Elmt (Elmt); | |
2230 | end loop; | |
2231 | ||
2232 | Next_Elmt (Vis_Ancestor); | |
2233 | end loop; | |
2234 | end if; | |
2235 | end; | |
2236 | end if; | |
2237 | ||
2238 | Next_Elmt (Elmt); | |
2239 | end loop; | |
2240 | ||
2241 | return Empty; | |
2242 | end Find_Hidden_Overridden_Primitive; | |
2243 | ||
ce2b6ba5 JM |
2244 | --------------------------------------- |
2245 | -- Find_Primitive_Covering_Interface -- | |
2246 | --------------------------------------- | |
2247 | ||
2248 | function Find_Primitive_Covering_Interface | |
2249 | (Tagged_Type : Entity_Id; | |
2250 | Iface_Prim : Entity_Id) return Entity_Id | |
2251 | is | |
92817e89 AC |
2252 | E : Entity_Id; |
2253 | El : Elmt_Id; | |
ce2b6ba5 JM |
2254 | |
2255 | begin | |
2256 | pragma Assert (Is_Interface (Find_Dispatching_Type (Iface_Prim)) | |
2257 | or else (Present (Alias (Iface_Prim)) | |
329b9f81 AC |
2258 | and then |
2259 | Is_Interface | |
2260 | (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim))))); | |
ce2b6ba5 | 2261 | |
947430d5 AC |
2262 | -- Search in the homonym chain. Done to speed up locating visible |
2263 | -- entities and required to catch primitives associated with the partial | |
2264 | -- view of private types when processing the corresponding full view. | |
92817e89 | 2265 | |
ce2b6ba5 JM |
2266 | E := Current_Entity (Iface_Prim); |
2267 | while Present (E) loop | |
2268 | if Is_Subprogram (E) | |
2269 | and then Is_Dispatching_Operation (E) | |
2270 | and then Is_Interface_Conformant (Tagged_Type, Iface_Prim, E) | |
2271 | then | |
2272 | return E; | |
2273 | end if; | |
2274 | ||
2275 | E := Homonym (E); | |
2276 | end loop; | |
2277 | ||
03459f40 AC |
2278 | -- Search in the list of primitives of the type. Required to locate |
2279 | -- the covering primitive if the covering primitive is not visible | |
2280 | -- (for example, non-visible inherited primitive of private type). | |
92817e89 AC |
2281 | |
2282 | El := First_Elmt (Primitive_Operations (Tagged_Type)); | |
2283 | while Present (El) loop | |
2284 | E := Node (El); | |
2285 | ||
947430d5 AC |
2286 | -- Keep separate the management of internal entities that link |
2287 | -- primitives with interface primitives from tagged type primitives. | |
2288 | ||
2289 | if No (Interface_Alias (E)) then | |
2290 | if Present (Alias (E)) then | |
2291 | ||
2292 | -- This interface primitive has not been covered yet | |
2293 | ||
2294 | if Alias (E) = Iface_Prim then | |
2295 | return E; | |
2296 | ||
2297 | -- The covering primitive was inherited | |
2298 | ||
2299 | elsif Overridden_Operation (Ultimate_Alias (E)) | |
2300 | = Iface_Prim | |
2301 | then | |
2302 | return E; | |
2303 | end if; | |
2304 | end if; | |
2305 | ||
ce09f8b3 | 2306 | -- Check if E covers the interface primitive (includes case in |
878f708a | 2307 | -- which E is an inherited private primitive). |
ce09f8b3 AC |
2308 | |
2309 | if Is_Interface_Conformant (Tagged_Type, Iface_Prim, E) then | |
2310 | return E; | |
2311 | end if; | |
2312 | ||
947430d5 | 2313 | -- Use the internal entity that links the interface primitive with |
329b9f81 | 2314 | -- the covering primitive to locate the entity. |
947430d5 AC |
2315 | |
2316 | elsif Interface_Alias (E) = Iface_Prim then | |
2317 | return Alias (E); | |
92817e89 AC |
2318 | end if; |
2319 | ||
2320 | Next_Elmt (El); | |
2321 | end loop; | |
2322 | ||
2323 | -- Not found | |
2324 | ||
ce2b6ba5 JM |
2325 | return Empty; |
2326 | end Find_Primitive_Covering_Interface; | |
2327 | ||
beacce02 | 2328 | --------------------------- |
cc821e65 | 2329 | -- Inheritance_Utilities -- |
beacce02 AC |
2330 | --------------------------- |
2331 | ||
cc821e65 | 2332 | package body Inheritance_Utilities is |
beacce02 | 2333 | |
cc821e65 CD |
2334 | --------------------------- |
2335 | -- Inherited_Subprograms -- | |
2336 | --------------------------- | |
beacce02 | 2337 | |
cc821e65 CD |
2338 | function Inherited_Subprograms |
2339 | (S : Entity_Id; | |
2340 | No_Interfaces : Boolean := False; | |
2341 | Interfaces_Only : Boolean := False; | |
2342 | One_Only : Boolean := False) return Subprogram_List | |
2343 | is | |
2344 | Result : Subprogram_List (1 .. 6000); | |
2345 | -- 6000 here is intended to be infinity. We could use an expandable | |
2346 | -- table, but it would be awfully heavy, and there is no way that we | |
2347 | -- could reasonably exceed this value. | |
beacce02 | 2348 | |
f537fc00 | 2349 | N : Nat := 0; |
cc821e65 | 2350 | -- Number of entries in Result |
1fb00064 | 2351 | |
cc821e65 CD |
2352 | Parent_Op : Entity_Id; |
2353 | -- Traverses the Overridden_Operation chain | |
1fb00064 | 2354 | |
cc821e65 CD |
2355 | procedure Store_IS (E : Entity_Id); |
2356 | -- Stores E in Result if not already stored | |
1fb00064 | 2357 | |
cc821e65 CD |
2358 | -------------- |
2359 | -- Store_IS -- | |
2360 | -------------- | |
1fb00064 | 2361 | |
cc821e65 CD |
2362 | procedure Store_IS (E : Entity_Id) is |
2363 | begin | |
2364 | for J in 1 .. N loop | |
2365 | if E = Result (J) then | |
2366 | return; | |
2367 | end if; | |
2368 | end loop; | |
1fb00064 | 2369 | |
cc821e65 CD |
2370 | N := N + 1; |
2371 | Result (N) := E; | |
2372 | end Store_IS; | |
eefe9555 | 2373 | |
f537fc00 | 2374 | -- Start of processing for Inherited_Subprograms |
beacce02 | 2375 | |
cc821e65 CD |
2376 | begin |
2377 | pragma Assert (not (No_Interfaces and Interfaces_Only)); | |
beacce02 | 2378 | |
cc821e65 CD |
2379 | -- When used from backends, visibility can be handled differently |
2380 | -- resulting in no dispatching type being found. | |
eefe9555 | 2381 | |
cc821e65 CD |
2382 | if Present (S) |
2383 | and then Is_Dispatching_Operation (S) | |
2384 | and then Present (Find_DT (S)) | |
2385 | then | |
cc821e65 CD |
2386 | -- Deal with direct inheritance |
2387 | ||
2388 | if not Interfaces_Only then | |
2389 | Parent_Op := S; | |
2390 | loop | |
2391 | Parent_Op := Overridden_Operation (Parent_Op); | |
2392 | exit when No (Parent_Op) | |
f537fc00 HK |
2393 | or else (No_Interfaces |
2394 | and then Is_Interface (Find_DT (Parent_Op))); | |
cc821e65 CD |
2395 | |
2396 | if Is_Subprogram_Or_Generic_Subprogram (Parent_Op) then | |
2397 | Store_IS (Parent_Op); | |
2398 | ||
2399 | if One_Only then | |
2400 | goto Done; | |
2401 | end if; | |
3a37ecec | 2402 | end if; |
cc821e65 CD |
2403 | end loop; |
2404 | end if; | |
beacce02 | 2405 | |
cc821e65 | 2406 | -- Now deal with interfaces |
1fb00064 | 2407 | |
cc821e65 CD |
2408 | if not No_Interfaces then |
2409 | declare | |
2410 | Tag_Typ : Entity_Id; | |
2411 | Prim : Entity_Id; | |
2412 | Elmt : Elmt_Id; | |
1fb00064 | 2413 | |
cc821e65 CD |
2414 | begin |
2415 | Tag_Typ := Find_DT (S); | |
1fb00064 | 2416 | |
cc821e65 CD |
2417 | -- In the presence of limited views there may be no visible |
2418 | -- dispatching type. Primitives will be inherited when non- | |
2419 | -- limited view is frozen. | |
167b47d9 | 2420 | |
cc821e65 CD |
2421 | if No (Tag_Typ) then |
2422 | return Result (1 .. 0); | |
2423 | end if; | |
167b47d9 | 2424 | |
cc821e65 CD |
2425 | if Is_Concurrent_Type (Tag_Typ) then |
2426 | Tag_Typ := Corresponding_Record_Type (Tag_Typ); | |
2427 | end if; | |
beacce02 | 2428 | |
cc821e65 | 2429 | -- Search primitive operations of dispatching type |
1fb00064 | 2430 | |
cc821e65 CD |
2431 | if Present (Tag_Typ) |
2432 | and then Present (Primitive_Operations (Tag_Typ)) | |
2433 | then | |
2434 | Elmt := First_Elmt (Primitive_Operations (Tag_Typ)); | |
2435 | while Present (Elmt) loop | |
2436 | Prim := Node (Elmt); | |
1fb00064 | 2437 | |
cc821e65 CD |
2438 | -- The following test eliminates some odd cases in |
2439 | -- which Ekind (Prim) is Void, to be investigated | |
2440 | -- further ??? | |
1fb00064 | 2441 | |
cc821e65 CD |
2442 | if not Is_Subprogram_Or_Generic_Subprogram (Prim) then |
2443 | null; | |
1fb00064 | 2444 | |
cc821e65 CD |
2445 | -- For [generic] subprogram, look at interface |
2446 | -- alias. | |
1fb00064 | 2447 | |
cc821e65 CD |
2448 | elsif Present (Interface_Alias (Prim)) |
2449 | and then Alias (Prim) = S | |
2450 | then | |
2451 | -- We have found a primitive covered by S | |
1fb00064 | 2452 | |
cc821e65 | 2453 | Store_IS (Interface_Alias (Prim)); |
3a37ecec | 2454 | |
cc821e65 CD |
2455 | if One_Only then |
2456 | goto Done; | |
2457 | end if; | |
3a37ecec | 2458 | end if; |
1fb00064 | 2459 | |
cc821e65 CD |
2460 | Next_Elmt (Elmt); |
2461 | end loop; | |
2462 | end if; | |
2463 | end; | |
2464 | end if; | |
eefe9555 | 2465 | end if; |
beacce02 | 2466 | |
cc821e65 CD |
2467 | <<Done>> |
2468 | ||
2469 | return Result (1 .. N); | |
2470 | end Inherited_Subprograms; | |
3a37ecec | 2471 | |
cc821e65 CD |
2472 | ------------------------------ |
2473 | -- Is_Overriding_Subprogram -- | |
2474 | ------------------------------ | |
2475 | ||
2476 | function Is_Overriding_Subprogram (E : Entity_Id) return Boolean is | |
2477 | Inherited : constant Subprogram_List := | |
2478 | Inherited_Subprograms (E, One_Only => True); | |
2479 | begin | |
2480 | return Inherited'Length > 0; | |
2481 | end Is_Overriding_Subprogram; | |
2482 | end Inheritance_Utilities; | |
2483 | ||
2484 | -------------------------------- | |
2485 | -- Inheritance_Utilities_Inst -- | |
2486 | -------------------------------- | |
2487 | ||
2488 | package Inheritance_Utilities_Inst is new | |
2489 | Inheritance_Utilities (Find_Dispatching_Type); | |
2490 | ||
2491 | --------------------------- | |
2492 | -- Inherited_Subprograms -- | |
2493 | --------------------------- | |
2494 | ||
2495 | function Inherited_Subprograms | |
2496 | (S : Entity_Id; | |
2497 | No_Interfaces : Boolean := False; | |
2498 | Interfaces_Only : Boolean := False; | |
2499 | One_Only : Boolean := False) return Subprogram_List renames | |
2500 | Inheritance_Utilities_Inst.Inherited_Subprograms; | |
beacce02 | 2501 | |
996ae0b0 RK |
2502 | --------------------------- |
2503 | -- Is_Dynamically_Tagged -- | |
2504 | --------------------------- | |
2505 | ||
2506 | function Is_Dynamically_Tagged (N : Node_Id) return Boolean is | |
2507 | begin | |
f9c0d38c JM |
2508 | if Nkind (N) = N_Error then |
2509 | return False; | |
b6dd03dd ES |
2510 | |
2511 | elsif Present (Find_Controlling_Arg (N)) then | |
2512 | return True; | |
2513 | ||
3b506eef | 2514 | -- Special cases: entities, and calls that dispatch on result |
b6dd03dd ES |
2515 | |
2516 | elsif Is_Entity_Name (N) then | |
2517 | return Is_Class_Wide_Type (Etype (N)); | |
2518 | ||
2519 | elsif Nkind (N) = N_Function_Call | |
2520 | and then Is_Class_Wide_Type (Etype (N)) | |
2521 | then | |
2522 | return True; | |
2523 | ||
3b506eef | 2524 | -- Otherwise check whether call has controlling argument |
b6dd03dd | 2525 | |
f9c0d38c | 2526 | else |
b6dd03dd | 2527 | return False; |
f9c0d38c | 2528 | end if; |
996ae0b0 RK |
2529 | end Is_Dynamically_Tagged; |
2530 | ||
0052da20 JM |
2531 | --------------------------------- |
2532 | -- Is_Null_Interface_Primitive -- | |
2533 | --------------------------------- | |
2534 | ||
2535 | function Is_Null_Interface_Primitive (E : Entity_Id) return Boolean is | |
2536 | begin | |
2537 | return Comes_From_Source (E) | |
2538 | and then Is_Dispatching_Operation (E) | |
2539 | and then Ekind (E) = E_Procedure | |
2540 | and then Null_Present (Parent (E)) | |
2541 | and then Is_Interface (Find_Dispatching_Type (E)); | |
2542 | end Is_Null_Interface_Primitive; | |
2543 | ||
7b4ebba5 AC |
2544 | ----------------------------------- |
2545 | -- Is_Inherited_Public_Operation -- | |
2546 | ----------------------------------- | |
2547 | ||
2548 | function Is_Inherited_Public_Operation (Op : Entity_Id) return Boolean is | |
9ac3cbb3 | 2549 | Pack_Decl : Node_Id; |
7cc7f3aa PMR |
2550 | Prim : Entity_Id := Op; |
2551 | Scop : Entity_Id := Prim; | |
7b4ebba5 AC |
2552 | |
2553 | begin | |
7cc7f3aa PMR |
2554 | -- Locate the ultimate non-hidden alias entity |
2555 | ||
2556 | while Present (Alias (Prim)) and then not Is_Hidden (Alias (Prim)) loop | |
2557 | pragma Assert (Alias (Prim) /= Prim); | |
2558 | Prim := Alias (Prim); | |
2559 | Scop := Scope (Prim); | |
2560 | end loop; | |
2561 | ||
7b4ebba5 AC |
2562 | if Comes_From_Source (Prim) and then Ekind (Scop) = E_Package then |
2563 | Pack_Decl := Unit_Declaration_Node (Scop); | |
9ac3cbb3 PMR |
2564 | |
2565 | return | |
2566 | Nkind (Pack_Decl) = N_Package_Declaration | |
2567 | and then List_Containing (Unit_Declaration_Node (Prim)) = | |
2568 | Visible_Declarations (Specification (Pack_Decl)); | |
7b4ebba5 AC |
2569 | |
2570 | else | |
2571 | return False; | |
2572 | end if; | |
2573 | end Is_Inherited_Public_Operation; | |
2574 | ||
90a4b336 YM |
2575 | ------------------------------ |
2576 | -- Is_Overriding_Subprogram -- | |
2577 | ------------------------------ | |
2578 | ||
cc821e65 CD |
2579 | function Is_Overriding_Subprogram (E : Entity_Id) return Boolean renames |
2580 | Inheritance_Utilities_Inst.Is_Overriding_Subprogram; | |
90a4b336 | 2581 | |
996ae0b0 RK |
2582 | -------------------------- |
2583 | -- Is_Tag_Indeterminate -- | |
2584 | -------------------------- | |
2585 | ||
2586 | function Is_Tag_Indeterminate (N : Node_Id) return Boolean is | |
2587 | Nam : Entity_Id; | |
2588 | Actual : Node_Id; | |
2589 | Orig_Node : constant Node_Id := Original_Node (N); | |
2590 | ||
2591 | begin | |
2592 | if Nkind (Orig_Node) = N_Function_Call | |
2593 | and then Is_Entity_Name (Name (Orig_Node)) | |
2594 | then | |
2595 | Nam := Entity (Name (Orig_Node)); | |
2596 | ||
2597 | if not Has_Controlling_Result (Nam) then | |
2598 | return False; | |
2599 | ||
243cae0a AC |
2600 | -- The function may have a controlling result, but if the return type |
2601 | -- is not visibly tagged, then this is not tag-indeterminate. | |
2602 | ||
2603 | elsif Is_Access_Type (Etype (Nam)) | |
2604 | and then not Is_Tagged_Type (Designated_Type (Etype (Nam))) | |
2605 | then | |
2606 | return False; | |
2607 | ||
fbf5a39b AC |
2608 | -- An explicit dereference means that the call has already been |
2609 | -- expanded and there is no tag to propagate. | |
2610 | ||
2611 | elsif Nkind (N) = N_Explicit_Dereference then | |
2612 | return False; | |
2613 | ||
996ae0b0 RK |
2614 | -- If there are no actuals, the call is tag-indeterminate |
2615 | ||
2616 | elsif No (Parameter_Associations (Orig_Node)) then | |
2617 | return True; | |
2618 | ||
2619 | else | |
2620 | Actual := First_Actual (Orig_Node); | |
996ae0b0 RK |
2621 | while Present (Actual) loop |
2622 | if Is_Controlling_Actual (Actual) | |
2623 | and then not Is_Tag_Indeterminate (Actual) | |
2624 | then | |
243cae0a AC |
2625 | -- One operand is dispatching |
2626 | ||
2627 | return False; | |
996ae0b0 RK |
2628 | end if; |
2629 | ||
2630 | Next_Actual (Actual); | |
2631 | end loop; | |
2632 | ||
2633 | return True; | |
996ae0b0 RK |
2634 | end if; |
2635 | ||
2636 | elsif Nkind (Orig_Node) = N_Qualified_Expression then | |
2637 | return Is_Tag_Indeterminate (Expression (Orig_Node)); | |
2638 | ||
3bcd6930 JM |
2639 | -- Case of a call to the Input attribute (possibly rewritten), which is |
2640 | -- always tag-indeterminate except when its prefix is a Class attribute. | |
2641 | ||
2642 | elsif Nkind (Orig_Node) = N_Attribute_Reference | |
2643 | and then | |
2644 | Get_Attribute_Id (Attribute_Name (Orig_Node)) = Attribute_Input | |
7b4ebba5 | 2645 | and then Nkind (Prefix (Orig_Node)) /= N_Attribute_Reference |
3bcd6930 JM |
2646 | then |
2647 | return True; | |
67f3c450 | 2648 | |
243cae0a AC |
2649 | -- In Ada 2005, a function that returns an anonymous access type can be |
2650 | -- dispatching, and the dereference of a call to such a function can | |
2651 | -- also be tag-indeterminate if the call itself is. | |
67f3c450 HK |
2652 | |
2653 | elsif Nkind (Orig_Node) = N_Explicit_Dereference | |
0791fbe9 | 2654 | and then Ada_Version >= Ada_2005 |
67f3c450 HK |
2655 | then |
2656 | return Is_Tag_Indeterminate (Prefix (Orig_Node)); | |
2657 | ||
996ae0b0 RK |
2658 | else |
2659 | return False; | |
2660 | end if; | |
2661 | end Is_Tag_Indeterminate; | |
2662 | ||
2663 | ------------------------------------ | |
2664 | -- Override_Dispatching_Operation -- | |
2665 | ------------------------------------ | |
2666 | ||
2667 | procedure Override_Dispatching_Operation | |
2668 | (Tagged_Type : Entity_Id; | |
2669 | Prev_Op : Entity_Id; | |
c37c13e1 | 2670 | New_Op : Entity_Id) |
996ae0b0 | 2671 | is |
67f3c450 HK |
2672 | Elmt : Elmt_Id; |
2673 | Prim : Node_Id; | |
996ae0b0 RK |
2674 | |
2675 | begin | |
67f3c450 HK |
2676 | -- If there is no previous operation to override, the type declaration |
2677 | -- was malformed, and an error must have been emitted already. | |
996ae0b0 | 2678 | |
67f3c450 | 2679 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); |
7b4ebba5 | 2680 | while Present (Elmt) and then Node (Elmt) /= Prev_Op loop |
67f3c450 | 2681 | Next_Elmt (Elmt); |
996ae0b0 RK |
2682 | end loop; |
2683 | ||
67f3c450 | 2684 | if No (Elmt) then |
996ae0b0 RK |
2685 | return; |
2686 | end if; | |
2687 | ||
74853971 AC |
2688 | -- The location of entities that come from source in the list of |
2689 | -- primitives of the tagged type must follow their order of occurrence | |
308e6f3a | 2690 | -- in the sources to fulfill the C++ ABI. If the overridden entity is a |
05dbd302 AC |
2691 | -- primitive of an interface that is not implemented by the parents of |
2692 | -- this tagged type (that is, it is an alias of an interface primitive | |
2693 | -- generated by Derive_Interface_Progenitors), then we must append the | |
2694 | -- new entity at the end of the list of primitives. | |
74853971 AC |
2695 | |
2696 | if Present (Alias (Prev_Op)) | |
05dbd302 | 2697 | and then Etype (Tagged_Type) /= Tagged_Type |
74853971 AC |
2698 | and then Is_Interface (Find_Dispatching_Type (Alias (Prev_Op))) |
2699 | and then not Is_Ancestor (Find_Dispatching_Type (Alias (Prev_Op)), | |
4ac2477e | 2700 | Tagged_Type, Use_Full_View => True) |
05dbd302 AC |
2701 | and then not Implements_Interface |
2702 | (Etype (Tagged_Type), | |
2703 | Find_Dispatching_Type (Alias (Prev_Op))) | |
74853971 AC |
2704 | then |
2705 | Remove_Elmt (Primitive_Operations (Tagged_Type), Elmt); | |
9057bd6a | 2706 | Add_Dispatching_Operation (Tagged_Type, New_Op); |
74853971 | 2707 | |
308e6f3a | 2708 | -- The new primitive replaces the overridden entity. Required to ensure |
74853971 AC |
2709 | -- that overriding primitive is assigned the same dispatch table slot. |
2710 | ||
2711 | else | |
2712 | Replace_Elmt (Elmt, New_Op); | |
2713 | end if; | |
3bcd6930 | 2714 | |
7b4ebba5 AC |
2715 | if Ada_Version >= Ada_2005 and then Has_Interfaces (Tagged_Type) then |
2716 | ||
67f3c450 | 2717 | -- Ada 2005 (AI-251): Update the attribute alias of all the aliased |
03459f40 AC |
2718 | -- entities of the overridden primitive to reference New_Op, and |
2719 | -- also propagate the proper value of Is_Abstract_Subprogram. Verify | |
ace980d5 ES |
2720 | -- that the new operation is subtype conformant with the interface |
2721 | -- operations that it implements (for operations inherited from the | |
2722 | -- parent itself, this check is made when building the derived type). | |
758c442c | 2723 | |
8398e82e AC |
2724 | -- Note: This code is executed with internally generated wrappers of |
2725 | -- functions with controlling result and late overridings. | |
ce2b6ba5 | 2726 | |
67f3c450 HK |
2727 | Elmt := First_Elmt (Primitive_Operations (Tagged_Type)); |
2728 | while Present (Elmt) loop | |
2729 | Prim := Node (Elmt); | |
758c442c | 2730 | |
67f3c450 HK |
2731 | if Prim = New_Op then |
2732 | null; | |
758c442c | 2733 | |
f9c0d38c JM |
2734 | -- Note: The check on Is_Subprogram protects the frontend against |
2735 | -- reading attributes in entities that are not yet fully decorated | |
2736 | ||
2737 | elsif Is_Subprogram (Prim) | |
ce2b6ba5 | 2738 | and then Present (Interface_Alias (Prim)) |
67f3c450 HK |
2739 | and then Alias (Prim) = Prev_Op |
2740 | then | |
2741 | Set_Alias (Prim, New_Op); | |
758c442c | 2742 | |
8398e82e AC |
2743 | -- No further decoration needed yet for internally generated |
2744 | -- wrappers of controlling functions since (at this stage) | |
2745 | -- they are not yet decorated. | |
2746 | ||
c37c13e1 | 2747 | if not Is_Wrapper (New_Op) then |
8398e82e AC |
2748 | Check_Subtype_Conformant (New_Op, Prim); |
2749 | ||
2750 | Set_Is_Abstract_Subprogram (Prim, | |
2751 | Is_Abstract_Subprogram (New_Op)); | |
67f3c450 | 2752 | |
8398e82e AC |
2753 | -- Ensure that this entity will be expanded to fill the |
2754 | -- corresponding entry in its dispatch table. | |
2755 | ||
2756 | if not Is_Abstract_Subprogram (Prim) then | |
2757 | Set_Has_Delayed_Freeze (Prim); | |
2758 | end if; | |
67f3c450 | 2759 | end if; |
758c442c GD |
2760 | end if; |
2761 | ||
2762 | Next_Elmt (Elmt); | |
2763 | end loop; | |
758c442c | 2764 | end if; |
996ae0b0 | 2765 | |
5dcc05e6 | 2766 | if (not Is_Package_Or_Generic_Package (Current_Scope)) |
996ae0b0 RK |
2767 | or else not In_Private_Part (Current_Scope) |
2768 | then | |
2769 | -- Not a private primitive | |
2770 | ||
2771 | null; | |
2772 | ||
2773 | else pragma Assert (Is_Inherited_Operation (Prev_Op)); | |
2774 | ||
2775 | -- Make the overriding operation into an alias of the implicit one. | |
3bcd6930 | 2776 | -- In this fashion a call from outside ends up calling the new body |
329b9f81 AC |
2777 | -- even if non-dispatching, and a call from inside calls the over- |
2778 | -- riding operation because it hides the implicit one. To indicate | |
2779 | -- that the body of Prev_Op is never called, set its dispatch table | |
2780 | -- entity to Empty. If the overridden operation has a dispatching | |
2781 | -- result, so does the overriding one. | |
996ae0b0 RK |
2782 | |
2783 | Set_Alias (Prev_Op, New_Op); | |
2784 | Set_DTC_Entity (Prev_Op, Empty); | |
c6f39437 | 2785 | Set_Has_Controlling_Result (New_Op, Has_Controlling_Result (Prev_Op)); |
07537fe6 | 2786 | Set_Is_Ada_2022_Only (New_Op, Is_Ada_2022_Only (Prev_Op)); |
996ae0b0 RK |
2787 | end if; |
2788 | end Override_Dispatching_Operation; | |
2789 | ||
2790 | ------------------- | |
2791 | -- Propagate_Tag -- | |
2792 | ------------------- | |
2793 | ||
2794 | procedure Propagate_Tag (Control : Node_Id; Actual : Node_Id) is | |
2795 | Call_Node : Node_Id; | |
2796 | Arg : Node_Id; | |
2797 | ||
2798 | begin | |
2799 | if Nkind (Actual) = N_Function_Call then | |
2800 | Call_Node := Actual; | |
2801 | ||
2802 | elsif Nkind (Actual) = N_Identifier | |
2803 | and then Nkind (Original_Node (Actual)) = N_Function_Call | |
2804 | then | |
0e41a941 AC |
2805 | -- Call rewritten as object declaration when stack-checking is |
2806 | -- enabled. Propagate tag to expression in declaration, which is | |
2807 | -- original call. | |
996ae0b0 RK |
2808 | |
2809 | Call_Node := Expression (Parent (Entity (Actual))); | |
2810 | ||
67f3c450 HK |
2811 | -- Ada 2005: If this is a dereference of a call to a function with a |
2812 | -- dispatching access-result, the tag is propagated when the dereference | |
2813 | -- itself is expanded (see exp_ch6.adb) and there is nothing else to do. | |
2814 | ||
2815 | elsif Nkind (Actual) = N_Explicit_Dereference | |
2816 | and then Nkind (Original_Node (Prefix (Actual))) = N_Function_Call | |
2817 | then | |
2818 | return; | |
2819 | ||
11fa950b AC |
2820 | -- When expansion is suppressed, an unexpanded call to 'Input can occur, |
2821 | -- and in that case we can simply return. | |
2822 | ||
2823 | elsif Nkind (Actual) = N_Attribute_Reference then | |
2824 | pragma Assert (Attribute_Name (Actual) = Name_Input); | |
2825 | ||
2826 | return; | |
2827 | ||
3bcd6930 JM |
2828 | -- Only other possibilities are parenthesized or qualified expression, |
2829 | -- or an expander-generated unchecked conversion of a function call to | |
2830 | -- a stream Input attribute. | |
996ae0b0 RK |
2831 | |
2832 | else | |
2833 | Call_Node := Expression (Actual); | |
2834 | end if; | |
2835 | ||
7af1cf83 AC |
2836 | -- No action needed if the call has been already expanded |
2837 | ||
2838 | if Is_Expanded_Dispatching_Call (Call_Node) then | |
2839 | return; | |
2840 | end if; | |
2841 | ||
0e41a941 AC |
2842 | -- Do not set the Controlling_Argument if already set. This happens in |
2843 | -- the special case of _Input (see Exp_Attr, case Input). | |
996ae0b0 RK |
2844 | |
2845 | if No (Controlling_Argument (Call_Node)) then | |
2846 | Set_Controlling_Argument (Call_Node, Control); | |
2847 | end if; | |
2848 | ||
2849 | Arg := First_Actual (Call_Node); | |
996ae0b0 RK |
2850 | while Present (Arg) loop |
2851 | if Is_Tag_Indeterminate (Arg) then | |
2852 | Propagate_Tag (Control, Arg); | |
2853 | end if; | |
2854 | ||
2855 | Next_Actual (Arg); | |
2856 | end loop; | |
2857 | ||
535a8637 | 2858 | -- Expansion of dispatching calls is suppressed on VM targets, because |
0e41a941 AC |
2859 | -- the VM back-ends directly handle the generation of dispatching calls |
2860 | -- and would have to undo any expansion to an indirect call. | |
996ae0b0 | 2861 | |
1f110335 | 2862 | if Tagged_Type_Expansion then |
d69cf005 AC |
2863 | declare |
2864 | Call_Typ : constant Entity_Id := Etype (Call_Node); | |
2865 | ||
2866 | begin | |
2867 | Expand_Dispatching_Call (Call_Node); | |
2868 | ||
2869 | -- If the controlling argument is an interface type and the type | |
2870 | -- of Call_Node differs then we must add an implicit conversion to | |
2871 | -- force displacement of the pointer to the object to reference | |
2872 | -- the secondary dispatch table of the interface. | |
2873 | ||
2874 | if Is_Interface (Etype (Control)) | |
2875 | and then Etype (Control) /= Call_Typ | |
2876 | then | |
2877 | -- Cannot use Convert_To because the previous call to | |
2878 | -- Expand_Dispatching_Call leaves decorated the Call_Node | |
2879 | -- with the type of Control. | |
2880 | ||
2881 | Rewrite (Call_Node, | |
2882 | Make_Type_Conversion (Sloc (Call_Node), | |
2883 | Subtype_Mark => | |
2884 | New_Occurrence_Of (Etype (Control), Sloc (Call_Node)), | |
2885 | Expression => Relocate_Node (Call_Node))); | |
2886 | Set_Etype (Call_Node, Etype (Control)); | |
2887 | Set_Analyzed (Call_Node); | |
2888 | ||
f6f4d8d4 | 2889 | Expand_Interface_Conversion (Call_Node); |
d69cf005 AC |
2890 | end if; |
2891 | end; | |
f7d5442e ES |
2892 | |
2893 | -- Expansion of a dispatching call results in an indirect call, which in | |
2894 | -- turn causes current values to be killed (see Resolve_Call), so on VM | |
2895 | -- targets we do the call here to ensure consistent warnings between VM | |
2896 | -- and non-VM targets. | |
2897 | ||
2898 | else | |
2899 | Kill_Current_Values; | |
996ae0b0 RK |
2900 | end if; |
2901 | end Propagate_Tag; | |
2902 | ||
2903 | end Sem_Disp; |