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1 | ------------------------------------------------------------------------------ |
2 | -- -- | |
3 | -- GNAT COMPILER COMPONENTS -- | |
4 | -- -- | |
5 | -- S E M _ C H 6 -- | |
6 | -- -- | |
7 | -- B o d y -- | |
996ae0b0 | 8 | -- -- |
fbf5a39b | 9 | -- Copyright (C) 1992-2003, 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- -- | |
13 | -- ware Foundation; either version 2, or (at your option) any later ver- -- | |
14 | -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- | |
15 | -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- | |
16 | -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- | |
17 | -- for more details. You should have received a copy of the GNU General -- | |
18 | -- Public License distributed with GNAT; see file COPYING. If not, write -- | |
19 | -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- | |
20 | -- MA 02111-1307, USA. -- | |
21 | -- -- | |
22 | -- GNAT was originally developed by the GNAT team at New York University. -- | |
71ff80dc | 23 | -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
996ae0b0 RK |
24 | -- -- |
25 | ------------------------------------------------------------------------------ | |
26 | ||
27 | with Atree; use Atree; | |
28 | with Checks; use Checks; | |
29 | with Debug; use Debug; | |
30 | with Einfo; use Einfo; | |
31 | with Elists; use Elists; | |
32 | with Errout; use Errout; | |
33 | with Expander; use Expander; | |
34 | with Exp_Ch7; use Exp_Ch7; | |
fbf5a39b | 35 | with Fname; use Fname; |
996ae0b0 RK |
36 | with Freeze; use Freeze; |
37 | with Lib.Xref; use Lib.Xref; | |
38 | with Namet; use Namet; | |
39 | with Lib; use Lib; | |
40 | with Nlists; use Nlists; | |
41 | with Nmake; use Nmake; | |
42 | with Opt; use Opt; | |
43 | with Output; use Output; | |
44 | with Rtsfind; use Rtsfind; | |
45 | with Sem; use Sem; | |
46 | with Sem_Cat; use Sem_Cat; | |
47 | with Sem_Ch3; use Sem_Ch3; | |
48 | with Sem_Ch4; use Sem_Ch4; | |
49 | with Sem_Ch5; use Sem_Ch5; | |
50 | with Sem_Ch8; use Sem_Ch8; | |
51 | with Sem_Ch12; use Sem_Ch12; | |
52 | with Sem_Disp; use Sem_Disp; | |
53 | with Sem_Dist; use Sem_Dist; | |
54 | with Sem_Elim; use Sem_Elim; | |
55 | with Sem_Eval; use Sem_Eval; | |
56 | with Sem_Mech; use Sem_Mech; | |
57 | with Sem_Prag; use Sem_Prag; | |
58 | with Sem_Res; use Sem_Res; | |
59 | with Sem_Util; use Sem_Util; | |
60 | with Sem_Type; use Sem_Type; | |
61 | with Sem_Warn; use Sem_Warn; | |
62 | with Sinput; use Sinput; | |
63 | with Stand; use Stand; | |
64 | with Sinfo; use Sinfo; | |
65 | with Sinfo.CN; use Sinfo.CN; | |
66 | with Snames; use Snames; | |
67 | with Stringt; use Stringt; | |
68 | with Style; | |
69 | with Stylesw; use Stylesw; | |
70 | with Tbuild; use Tbuild; | |
71 | with Uintp; use Uintp; | |
72 | with Urealp; use Urealp; | |
73 | with Validsw; use Validsw; | |
74 | ||
75 | package body Sem_Ch6 is | |
76 | ||
77 | ----------------------- | |
78 | -- Local Subprograms -- | |
79 | ----------------------- | |
80 | ||
81 | procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id); | |
fbf5a39b AC |
82 | -- Analyze a generic subprogram body. N is the body to be analyzed, |
83 | -- and Gen_Id is the defining entity Id for the corresponding spec. | |
996ae0b0 RK |
84 | |
85 | function Build_Body_To_Inline | |
86 | (N : Node_Id; | |
87 | Subp : Entity_Id; | |
88 | Orig_Body : Node_Id) | |
89 | return Boolean; | |
90 | -- If a subprogram has pragma Inline and inlining is active, use generic | |
91 | -- machinery to build an unexpanded body for the subprogram. This body is | |
92 | -- subsequenty used for inline expansions at call sites. If subprogram can | |
93 | -- be inlined (depending on size and nature of local declarations) this | |
94 | -- function returns true. Otherwise subprogram body is treated normally. | |
95 | ||
96 | type Conformance_Type is | |
97 | (Type_Conformant, Mode_Conformant, Subtype_Conformant, Fully_Conformant); | |
07fc65c4 GB |
98 | -- Conformance type used for following call, meaning matches the |
99 | -- RM definitions of the corresponding terms. | |
996ae0b0 RK |
100 | |
101 | procedure Check_Conformance | |
102 | (New_Id : Entity_Id; | |
103 | Old_Id : Entity_Id; | |
104 | Ctype : Conformance_Type; | |
105 | Errmsg : Boolean; | |
106 | Conforms : out Boolean; | |
107 | Err_Loc : Node_Id := Empty; | |
108 | Get_Inst : Boolean := False); | |
109 | -- Given two entities, this procedure checks that the profiles associated | |
110 | -- with these entities meet the conformance criterion given by the third | |
111 | -- parameter. If they conform, Conforms is set True and control returns | |
112 | -- to the caller. If they do not conform, Conforms is set to False, and | |
113 | -- in addition, if Errmsg is True on the call, proper messages are output | |
114 | -- to complain about the conformance failure. If Err_Loc is non_Empty | |
115 | -- the error messages are placed on Err_Loc, if Err_Loc is empty, then | |
116 | -- error messages are placed on the appropriate part of the construct | |
117 | -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance | |
118 | -- against a formal access-to-subprogram type so Get_Instance_Of must | |
119 | -- be called. | |
120 | ||
fbf5a39b AC |
121 | procedure Check_Overriding_Operation |
122 | (N : Node_Id; | |
123 | Subp : Entity_Id); | |
124 | -- Check that a subprogram with a pragma Overriding or Optional_Overriding | |
125 | -- is legal. This check is performed here rather than in Sem_Prag because | |
126 | -- the pragma must follow immediately the declaration, and can be treated | |
127 | -- as part of the declaration itself, as described in AI-218. | |
128 | ||
996ae0b0 RK |
129 | procedure Check_Subprogram_Order (N : Node_Id); |
130 | -- N is the N_Subprogram_Body node for a subprogram. This routine applies | |
131 | -- the alpha ordering rule for N if this ordering requirement applicable. | |
132 | ||
133 | function Is_Non_Overriding_Operation | |
134 | (Prev_E : Entity_Id; | |
135 | New_E : Entity_Id) | |
136 | return Boolean; | |
137 | -- Enforce the rule given in 12.3(18): a private operation in an instance | |
138 | -- overrides an inherited operation only if the corresponding operation | |
139 | -- was overriding in the generic. This can happen for primitive operations | |
140 | -- of types derived (in the generic unit) from formal private or formal | |
141 | -- derived types. | |
142 | ||
143 | procedure Check_Returns | |
144 | (HSS : Node_Id; | |
145 | Mode : Character; | |
146 | Err : out Boolean); | |
147 | -- Called to check for missing return statements in a function body, | |
148 | -- or for returns present in a procedure body which has No_Return set. | |
149 | -- L is the handled statement sequence for the subprogram body. This | |
150 | -- procedure checks all flow paths to make sure they either have a | |
151 | -- return (Mode = 'F') or do not have a return (Mode = 'P'). The flag | |
152 | -- Err is set if there are any control paths not explicitly terminated | |
153 | -- by a return in the function case, and is True otherwise. | |
154 | ||
155 | function Conforming_Types | |
156 | (T1 : Entity_Id; | |
157 | T2 : Entity_Id; | |
158 | Ctype : Conformance_Type; | |
159 | Get_Inst : Boolean := False) | |
160 | return Boolean; | |
161 | -- Check that two formal parameter types conform, checking both | |
162 | -- for equality of base types, and where required statically | |
163 | -- matching subtypes, depending on the setting of Ctype. | |
164 | ||
165 | procedure Enter_Overloaded_Entity (S : Entity_Id); | |
166 | -- This procedure makes S, a new overloaded entity, into the first | |
167 | -- visible entity with that name. | |
168 | ||
169 | procedure Install_Entity (E : Entity_Id); | |
170 | -- Make single entity visible. Used for generic formals as well. | |
171 | ||
172 | procedure Install_Formals (Id : Entity_Id); | |
173 | -- On entry to a subprogram body, make the formals visible. Note | |
174 | -- that simply placing the subprogram on the scope stack is not | |
175 | -- sufficient: the formals must become the current entities for | |
176 | -- their names. | |
177 | ||
178 | procedure Make_Inequality_Operator (S : Entity_Id); | |
179 | -- Create the declaration for an inequality operator that is implicitly | |
180 | -- created by a user-defined equality operator that yields a boolean. | |
181 | ||
182 | procedure May_Need_Actuals (Fun : Entity_Id); | |
183 | -- Flag functions that can be called without parameters, i.e. those that | |
184 | -- have no parameters, or those for which defaults exist for all parameters | |
185 | ||
fbf5a39b AC |
186 | procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id); |
187 | -- If there is a separate spec for a subprogram or generic subprogram, | |
188 | -- the formals of the body are treated as references to the corresponding | |
189 | -- formals of the spec. This reference does not count as an actual use of | |
190 | -- the formal, in order to diagnose formals that are unused in the body. | |
191 | ||
996ae0b0 RK |
192 | procedure Set_Formal_Validity (Formal_Id : Entity_Id); |
193 | -- Formal_Id is an formal parameter entity. This procedure deals with | |
194 | -- setting the proper validity status for this entity, which depends | |
195 | -- on the kind of parameter and the validity checking mode. | |
196 | ||
197 | --------------------------------------------- | |
198 | -- Analyze_Abstract_Subprogram_Declaration -- | |
199 | --------------------------------------------- | |
200 | ||
201 | procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is | |
fbf5a39b AC |
202 | Designator : constant Entity_Id := |
203 | Analyze_Subprogram_Specification (Specification (N)); | |
996ae0b0 RK |
204 | Scop : constant Entity_Id := Current_Scope; |
205 | ||
206 | begin | |
207 | Generate_Definition (Designator); | |
208 | Set_Is_Abstract (Designator); | |
209 | New_Overloaded_Entity (Designator); | |
210 | Check_Delayed_Subprogram (Designator); | |
211 | ||
fbf5a39b | 212 | Set_Categorization_From_Scope (Designator, Scop); |
996ae0b0 RK |
213 | |
214 | if Ekind (Scope (Designator)) = E_Protected_Type then | |
215 | Error_Msg_N | |
216 | ("abstract subprogram not allowed in protected type", N); | |
217 | end if; | |
fbf5a39b AC |
218 | |
219 | Generate_Reference_To_Formals (Designator); | |
996ae0b0 RK |
220 | end Analyze_Abstract_Subprogram_Declaration; |
221 | ||
222 | ---------------------------- | |
223 | -- Analyze_Function_Call -- | |
224 | ---------------------------- | |
225 | ||
226 | procedure Analyze_Function_Call (N : Node_Id) is | |
227 | P : constant Node_Id := Name (N); | |
228 | L : constant List_Id := Parameter_Associations (N); | |
229 | Actual : Node_Id; | |
230 | ||
231 | begin | |
232 | Analyze (P); | |
233 | ||
234 | -- If error analyzing name, then set Any_Type as result type and return | |
235 | ||
236 | if Etype (P) = Any_Type then | |
237 | Set_Etype (N, Any_Type); | |
238 | return; | |
239 | end if; | |
240 | ||
241 | -- Otherwise analyze the parameters | |
242 | ||
243 | if Present (L) then | |
244 | Actual := First (L); | |
245 | ||
246 | while Present (Actual) loop | |
247 | Analyze (Actual); | |
248 | Check_Parameterless_Call (Actual); | |
249 | Next (Actual); | |
250 | end loop; | |
251 | end if; | |
252 | ||
253 | Analyze_Call (N); | |
996ae0b0 RK |
254 | end Analyze_Function_Call; |
255 | ||
256 | ------------------------------------- | |
257 | -- Analyze_Generic_Subprogram_Body -- | |
258 | ------------------------------------- | |
259 | ||
260 | procedure Analyze_Generic_Subprogram_Body | |
261 | (N : Node_Id; | |
262 | Gen_Id : Entity_Id) | |
263 | is | |
fbf5a39b | 264 | Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id); |
996ae0b0 | 265 | Kind : constant Entity_Kind := Ekind (Gen_Id); |
fbf5a39b | 266 | Body_Id : Entity_Id; |
996ae0b0 | 267 | New_N : Node_Id; |
fbf5a39b | 268 | Spec : Node_Id; |
996ae0b0 RK |
269 | |
270 | begin | |
271 | -- Copy body and disable expansion while analyzing the generic | |
272 | -- For a stub, do not copy the stub (which would load the proper body), | |
273 | -- this will be done when the proper body is analyzed. | |
274 | ||
275 | if Nkind (N) /= N_Subprogram_Body_Stub then | |
276 | New_N := Copy_Generic_Node (N, Empty, Instantiating => False); | |
277 | Rewrite (N, New_N); | |
278 | Start_Generic; | |
279 | end if; | |
280 | ||
281 | Spec := Specification (N); | |
282 | ||
283 | -- Within the body of the generic, the subprogram is callable, and | |
284 | -- behaves like the corresponding non-generic unit. | |
285 | ||
fbf5a39b | 286 | Body_Id := Defining_Entity (Spec); |
996ae0b0 RK |
287 | |
288 | if Kind = E_Generic_Procedure | |
289 | and then Nkind (Spec) /= N_Procedure_Specification | |
290 | then | |
fbf5a39b | 291 | Error_Msg_N ("invalid body for generic procedure ", Body_Id); |
996ae0b0 RK |
292 | return; |
293 | ||
294 | elsif Kind = E_Generic_Function | |
295 | and then Nkind (Spec) /= N_Function_Specification | |
296 | then | |
fbf5a39b | 297 | Error_Msg_N ("invalid body for generic function ", Body_Id); |
996ae0b0 RK |
298 | return; |
299 | end if; | |
300 | ||
fbf5a39b | 301 | Set_Corresponding_Body (Gen_Decl, Body_Id); |
996ae0b0 RK |
302 | |
303 | if Has_Completion (Gen_Id) | |
304 | and then Nkind (Parent (N)) /= N_Subunit | |
305 | then | |
306 | Error_Msg_N ("duplicate generic body", N); | |
307 | return; | |
308 | else | |
309 | Set_Has_Completion (Gen_Id); | |
310 | end if; | |
311 | ||
312 | if Nkind (N) = N_Subprogram_Body_Stub then | |
313 | Set_Ekind (Defining_Entity (Specification (N)), Kind); | |
314 | else | |
315 | Set_Corresponding_Spec (N, Gen_Id); | |
316 | end if; | |
317 | ||
318 | if Nkind (Parent (N)) = N_Compilation_Unit then | |
319 | Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N)); | |
320 | end if; | |
321 | ||
322 | -- Make generic parameters immediately visible in the body. They are | |
323 | -- needed to process the formals declarations. Then make the formals | |
324 | -- visible in a separate step. | |
325 | ||
326 | New_Scope (Gen_Id); | |
327 | ||
328 | declare | |
329 | E : Entity_Id; | |
330 | First_Ent : Entity_Id; | |
331 | ||
332 | begin | |
333 | First_Ent := First_Entity (Gen_Id); | |
334 | ||
335 | E := First_Ent; | |
336 | while Present (E) and then not Is_Formal (E) loop | |
337 | Install_Entity (E); | |
338 | Next_Entity (E); | |
339 | end loop; | |
340 | ||
341 | Set_Use (Generic_Formal_Declarations (Gen_Decl)); | |
342 | ||
343 | -- Now generic formals are visible, and the specification can be | |
344 | -- analyzed, for subsequent conformance check. | |
345 | ||
fbf5a39b | 346 | Body_Id := Analyze_Subprogram_Specification (Spec); |
996ae0b0 | 347 | |
fbf5a39b | 348 | -- Make formal parameters visible |
996ae0b0 RK |
349 | |
350 | if Present (E) then | |
351 | ||
fbf5a39b AC |
352 | -- E is the first formal parameter, we loop through the formals |
353 | -- installing them so that they will be visible. | |
996ae0b0 RK |
354 | |
355 | Set_First_Entity (Gen_Id, E); | |
996ae0b0 RK |
356 | while Present (E) loop |
357 | Install_Entity (E); | |
358 | Next_Formal (E); | |
359 | end loop; | |
360 | end if; | |
361 | ||
362 | -- Visible generic entity is callable within its own body. | |
363 | ||
fbf5a39b AC |
364 | Set_Ekind (Gen_Id, Ekind (Body_Id)); |
365 | Set_Ekind (Body_Id, E_Subprogram_Body); | |
366 | Set_Convention (Body_Id, Convention (Gen_Id)); | |
367 | Set_Scope (Body_Id, Scope (Gen_Id)); | |
368 | Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id); | |
369 | ||
370 | if Nkind (N) = N_Subprogram_Body_Stub then | |
371 | ||
372 | -- No body to analyze, so restore state of generic unit. | |
373 | ||
374 | Set_Ekind (Gen_Id, Kind); | |
375 | Set_Ekind (Body_Id, Kind); | |
376 | ||
377 | if Present (First_Ent) then | |
378 | Set_First_Entity (Gen_Id, First_Ent); | |
379 | end if; | |
380 | ||
381 | End_Scope; | |
382 | return; | |
383 | end if; | |
996ae0b0 RK |
384 | |
385 | -- If this is a compilation unit, it must be made visible | |
386 | -- explicitly, because the compilation of the declaration, | |
387 | -- unlike other library unit declarations, does not. If it | |
388 | -- is not a unit, the following is redundant but harmless. | |
389 | ||
390 | Set_Is_Immediately_Visible (Gen_Id); | |
fbf5a39b | 391 | Reference_Body_Formals (Gen_Id, Body_Id); |
996ae0b0 RK |
392 | |
393 | Set_Actual_Subtypes (N, Current_Scope); | |
394 | Analyze_Declarations (Declarations (N)); | |
395 | Check_Completion; | |
396 | Analyze (Handled_Statement_Sequence (N)); | |
397 | ||
398 | Save_Global_References (Original_Node (N)); | |
399 | ||
400 | -- Prior to exiting the scope, include generic formals again | |
401 | -- (if any are present) in the set of local entities. | |
402 | ||
403 | if Present (First_Ent) then | |
404 | Set_First_Entity (Gen_Id, First_Ent); | |
405 | end if; | |
406 | ||
fbf5a39b | 407 | Check_References (Gen_Id); |
996ae0b0 RK |
408 | end; |
409 | ||
410 | End_Scope; | |
411 | Check_Subprogram_Order (N); | |
412 | ||
413 | -- Outside of its body, unit is generic again. | |
414 | ||
415 | Set_Ekind (Gen_Id, Kind); | |
fbf5a39b AC |
416 | Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False); |
417 | Style.Check_Identifier (Body_Id, Gen_Id); | |
996ae0b0 | 418 | End_Generic; |
996ae0b0 RK |
419 | end Analyze_Generic_Subprogram_Body; |
420 | ||
421 | ----------------------------- | |
422 | -- Analyze_Operator_Symbol -- | |
423 | ----------------------------- | |
424 | ||
425 | -- An operator symbol such as "+" or "and" may appear in context where | |
426 | -- the literal denotes an entity name, such as "+"(x, y) or in a | |
427 | -- context when it is just a string, as in (conjunction = "or"). In | |
428 | -- these cases the parser generates this node, and the semantics does | |
429 | -- the disambiguation. Other such case are actuals in an instantiation, | |
430 | -- the generic unit in an instantiation, and pragma arguments. | |
431 | ||
432 | procedure Analyze_Operator_Symbol (N : Node_Id) is | |
433 | Par : constant Node_Id := Parent (N); | |
434 | ||
435 | begin | |
436 | if (Nkind (Par) = N_Function_Call and then N = Name (Par)) | |
437 | or else Nkind (Par) = N_Function_Instantiation | |
438 | or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par)) | |
439 | or else (Nkind (Par) = N_Pragma_Argument_Association | |
440 | and then not Is_Pragma_String_Literal (Par)) | |
441 | or else Nkind (Par) = N_Subprogram_Renaming_Declaration | |
442 | or else (Nkind (Par) = N_Attribute_Reference | |
443 | and then Attribute_Name (Par) /= Name_Value) | |
444 | then | |
445 | Find_Direct_Name (N); | |
446 | ||
447 | else | |
448 | Change_Operator_Symbol_To_String_Literal (N); | |
449 | Analyze (N); | |
450 | end if; | |
451 | end Analyze_Operator_Symbol; | |
452 | ||
453 | ----------------------------------- | |
454 | -- Analyze_Parameter_Association -- | |
455 | ----------------------------------- | |
456 | ||
457 | procedure Analyze_Parameter_Association (N : Node_Id) is | |
458 | begin | |
459 | Analyze (Explicit_Actual_Parameter (N)); | |
460 | end Analyze_Parameter_Association; | |
461 | ||
462 | ---------------------------- | |
463 | -- Analyze_Procedure_Call -- | |
464 | ---------------------------- | |
465 | ||
466 | procedure Analyze_Procedure_Call (N : Node_Id) is | |
467 | Loc : constant Source_Ptr := Sloc (N); | |
468 | P : constant Node_Id := Name (N); | |
469 | Actuals : constant List_Id := Parameter_Associations (N); | |
470 | Actual : Node_Id; | |
471 | New_N : Node_Id; | |
472 | ||
473 | procedure Analyze_Call_And_Resolve; | |
474 | -- Do Analyze and Resolve calls for procedure call | |
475 | ||
fbf5a39b AC |
476 | ------------------------------ |
477 | -- Analyze_Call_And_Resolve -- | |
478 | ------------------------------ | |
479 | ||
996ae0b0 RK |
480 | procedure Analyze_Call_And_Resolve is |
481 | begin | |
482 | if Nkind (N) = N_Procedure_Call_Statement then | |
483 | Analyze_Call (N); | |
484 | Resolve (N, Standard_Void_Type); | |
485 | else | |
486 | Analyze (N); | |
487 | end if; | |
488 | end Analyze_Call_And_Resolve; | |
489 | ||
490 | -- Start of processing for Analyze_Procedure_Call | |
491 | ||
492 | begin | |
493 | -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote | |
494 | -- a procedure call or an entry call. The prefix may denote an access | |
495 | -- to subprogram type, in which case an implicit dereference applies. | |
496 | -- If the prefix is an indexed component (without implicit defererence) | |
497 | -- then the construct denotes a call to a member of an entire family. | |
498 | -- If the prefix is a simple name, it may still denote a call to a | |
499 | -- parameterless member of an entry family. Resolution of these various | |
500 | -- interpretations is delicate. | |
501 | ||
502 | Analyze (P); | |
503 | ||
504 | -- If error analyzing prefix, then set Any_Type as result and return | |
505 | ||
506 | if Etype (P) = Any_Type then | |
507 | Set_Etype (N, Any_Type); | |
508 | return; | |
509 | end if; | |
510 | ||
511 | -- Otherwise analyze the parameters | |
512 | ||
513 | if Present (Actuals) then | |
514 | Actual := First (Actuals); | |
515 | ||
516 | while Present (Actual) loop | |
517 | Analyze (Actual); | |
518 | Check_Parameterless_Call (Actual); | |
519 | Next (Actual); | |
520 | end loop; | |
521 | end if; | |
522 | ||
523 | -- Special processing for Elab_Spec and Elab_Body calls | |
524 | ||
525 | if Nkind (P) = N_Attribute_Reference | |
526 | and then (Attribute_Name (P) = Name_Elab_Spec | |
527 | or else Attribute_Name (P) = Name_Elab_Body) | |
528 | then | |
529 | if Present (Actuals) then | |
530 | Error_Msg_N | |
531 | ("no parameters allowed for this call", First (Actuals)); | |
532 | return; | |
533 | end if; | |
534 | ||
535 | Set_Etype (N, Standard_Void_Type); | |
536 | Set_Analyzed (N); | |
537 | ||
538 | elsif Is_Entity_Name (P) | |
539 | and then Is_Record_Type (Etype (Entity (P))) | |
540 | and then Remote_AST_I_Dereference (P) | |
541 | then | |
542 | return; | |
543 | ||
544 | elsif Is_Entity_Name (P) | |
545 | and then Ekind (Entity (P)) /= E_Entry_Family | |
546 | then | |
547 | if Is_Access_Type (Etype (P)) | |
548 | and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type | |
549 | and then No (Actuals) | |
550 | and then Comes_From_Source (N) | |
551 | then | |
552 | Error_Msg_N ("missing explicit dereference in call", N); | |
553 | end if; | |
554 | ||
555 | Analyze_Call_And_Resolve; | |
556 | ||
557 | -- If the prefix is the simple name of an entry family, this is | |
558 | -- a parameterless call from within the task body itself. | |
559 | ||
560 | elsif Is_Entity_Name (P) | |
561 | and then Nkind (P) = N_Identifier | |
562 | and then Ekind (Entity (P)) = E_Entry_Family | |
563 | and then Present (Actuals) | |
564 | and then No (Next (First (Actuals))) | |
565 | then | |
566 | -- Can be call to parameterless entry family. What appears to be | |
567 | -- the sole argument is in fact the entry index. Rewrite prefix | |
568 | -- of node accordingly. Source representation is unchanged by this | |
569 | -- transformation. | |
570 | ||
571 | New_N := | |
572 | Make_Indexed_Component (Loc, | |
573 | Prefix => | |
574 | Make_Selected_Component (Loc, | |
575 | Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc), | |
576 | Selector_Name => New_Occurrence_Of (Entity (P), Loc)), | |
577 | Expressions => Actuals); | |
578 | Set_Name (N, New_N); | |
579 | Set_Etype (New_N, Standard_Void_Type); | |
580 | Set_Parameter_Associations (N, No_List); | |
581 | Analyze_Call_And_Resolve; | |
582 | ||
583 | elsif Nkind (P) = N_Explicit_Dereference then | |
584 | if Ekind (Etype (P)) = E_Subprogram_Type then | |
585 | Analyze_Call_And_Resolve; | |
586 | else | |
587 | Error_Msg_N ("expect access to procedure in call", P); | |
588 | end if; | |
589 | ||
590 | -- The name can be a selected component or an indexed component | |
591 | -- that yields an access to subprogram. Such a prefix is legal if | |
592 | -- the call has parameter associations. | |
593 | ||
594 | elsif Is_Access_Type (Etype (P)) | |
595 | and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type | |
596 | then | |
597 | if Present (Actuals) then | |
598 | Analyze_Call_And_Resolve; | |
599 | else | |
600 | Error_Msg_N ("missing explicit dereference in call ", N); | |
601 | end if; | |
602 | ||
603 | -- If not an access to subprogram, then the prefix must resolve to | |
604 | -- the name of an entry, entry family, or protected operation. | |
605 | ||
606 | -- For the case of a simple entry call, P is a selected component | |
607 | -- where the prefix is the task and the selector name is the entry. | |
608 | -- A call to a protected procedure will have the same syntax. If | |
609 | -- the protected object contains overloaded operations, the entity | |
610 | -- may appear as a function, the context will select the operation | |
611 | -- whose type is Void. | |
612 | ||
613 | elsif Nkind (P) = N_Selected_Component | |
614 | and then (Ekind (Entity (Selector_Name (P))) = E_Entry | |
615 | or else | |
616 | Ekind (Entity (Selector_Name (P))) = E_Procedure | |
617 | or else | |
618 | Ekind (Entity (Selector_Name (P))) = E_Function) | |
619 | then | |
620 | Analyze_Call_And_Resolve; | |
621 | ||
622 | elsif Nkind (P) = N_Selected_Component | |
623 | and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family | |
624 | and then Present (Actuals) | |
625 | and then No (Next (First (Actuals))) | |
626 | then | |
627 | -- Can be call to parameterless entry family. What appears to be | |
628 | -- the sole argument is in fact the entry index. Rewrite prefix | |
629 | -- of node accordingly. Source representation is unchanged by this | |
630 | -- transformation. | |
631 | ||
632 | New_N := | |
633 | Make_Indexed_Component (Loc, | |
634 | Prefix => New_Copy (P), | |
635 | Expressions => Actuals); | |
636 | Set_Name (N, New_N); | |
637 | Set_Etype (New_N, Standard_Void_Type); | |
638 | Set_Parameter_Associations (N, No_List); | |
639 | Analyze_Call_And_Resolve; | |
640 | ||
641 | -- For the case of a reference to an element of an entry family, P is | |
642 | -- an indexed component whose prefix is a selected component (task and | |
643 | -- entry family), and whose index is the entry family index. | |
644 | ||
645 | elsif Nkind (P) = N_Indexed_Component | |
646 | and then Nkind (Prefix (P)) = N_Selected_Component | |
647 | and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family | |
648 | then | |
649 | Analyze_Call_And_Resolve; | |
650 | ||
651 | -- If the prefix is the name of an entry family, it is a call from | |
652 | -- within the task body itself. | |
653 | ||
654 | elsif Nkind (P) = N_Indexed_Component | |
655 | and then Nkind (Prefix (P)) = N_Identifier | |
656 | and then Ekind (Entity (Prefix (P))) = E_Entry_Family | |
657 | then | |
658 | New_N := | |
659 | Make_Selected_Component (Loc, | |
660 | Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc), | |
661 | Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc)); | |
662 | Rewrite (Prefix (P), New_N); | |
663 | Analyze (P); | |
664 | Analyze_Call_And_Resolve; | |
665 | ||
666 | -- Anything else is an error. | |
667 | ||
668 | else | |
669 | Error_Msg_N ("Invalid procedure or entry call", N); | |
670 | end if; | |
671 | end Analyze_Procedure_Call; | |
672 | ||
673 | ------------------------------ | |
674 | -- Analyze_Return_Statement -- | |
675 | ------------------------------ | |
676 | ||
677 | procedure Analyze_Return_Statement (N : Node_Id) is | |
678 | Loc : constant Source_Ptr := Sloc (N); | |
679 | Expr : Node_Id; | |
680 | Scope_Id : Entity_Id; | |
681 | Kind : Entity_Kind; | |
682 | R_Type : Entity_Id; | |
683 | ||
684 | begin | |
685 | -- Find subprogram or accept statement enclosing the return statement | |
686 | ||
687 | Scope_Id := Empty; | |
688 | for J in reverse 0 .. Scope_Stack.Last loop | |
689 | Scope_Id := Scope_Stack.Table (J).Entity; | |
690 | exit when Ekind (Scope_Id) /= E_Block and then | |
691 | Ekind (Scope_Id) /= E_Loop; | |
692 | end loop; | |
693 | ||
694 | pragma Assert (Present (Scope_Id)); | |
695 | ||
696 | Kind := Ekind (Scope_Id); | |
697 | Expr := Expression (N); | |
698 | ||
699 | if Kind /= E_Function | |
700 | and then Kind /= E_Generic_Function | |
701 | and then Kind /= E_Procedure | |
702 | and then Kind /= E_Generic_Procedure | |
703 | and then Kind /= E_Entry | |
704 | and then Kind /= E_Entry_Family | |
705 | then | |
706 | Error_Msg_N ("illegal context for return statement", N); | |
707 | ||
708 | elsif Present (Expr) then | |
709 | if Kind = E_Function or else Kind = E_Generic_Function then | |
710 | Set_Return_Present (Scope_Id); | |
711 | R_Type := Etype (Scope_Id); | |
712 | Set_Return_Type (N, R_Type); | |
713 | Analyze_And_Resolve (Expr, R_Type); | |
714 | ||
715 | if (Is_Class_Wide_Type (Etype (Expr)) | |
716 | or else Is_Dynamically_Tagged (Expr)) | |
717 | and then not Is_Class_Wide_Type (R_Type) | |
718 | then | |
719 | Error_Msg_N | |
720 | ("dynamically tagged expression not allowed!", Expr); | |
721 | end if; | |
722 | ||
723 | Apply_Constraint_Check (Expr, R_Type); | |
724 | ||
725 | -- ??? A real run-time accessibility check is needed | |
726 | -- in cases involving dereferences of access parameters. | |
727 | -- For now we just check the static cases. | |
728 | ||
729 | if Is_Return_By_Reference_Type (Etype (Scope_Id)) | |
730 | and then Object_Access_Level (Expr) | |
731 | > Subprogram_Access_Level (Scope_Id) | |
732 | then | |
07fc65c4 GB |
733 | Rewrite (N, |
734 | Make_Raise_Program_Error (Loc, | |
735 | Reason => PE_Accessibility_Check_Failed)); | |
996ae0b0 RK |
736 | Analyze (N); |
737 | ||
738 | Error_Msg_N | |
739 | ("cannot return a local value by reference?", N); | |
740 | Error_Msg_NE | |
741 | ("& will be raised at run time?!", | |
742 | N, Standard_Program_Error); | |
743 | end if; | |
744 | ||
745 | elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then | |
746 | Error_Msg_N ("procedure cannot return value (use function)", N); | |
747 | ||
748 | else | |
749 | Error_Msg_N ("accept statement cannot return value", N); | |
750 | end if; | |
751 | ||
752 | -- No expression present | |
753 | ||
754 | else | |
755 | if Kind = E_Function or Kind = E_Generic_Function then | |
756 | Error_Msg_N ("missing expression in return from function", N); | |
757 | end if; | |
758 | ||
759 | if (Ekind (Scope_Id) = E_Procedure | |
760 | or else Ekind (Scope_Id) = E_Generic_Procedure) | |
fbf5a39b | 761 | and then No_Return (Scope_Id) |
996ae0b0 RK |
762 | then |
763 | Error_Msg_N | |
764 | ("RETURN statement not allowed (No_Return)", N); | |
765 | end if; | |
766 | end if; | |
767 | ||
768 | Check_Unreachable_Code (N); | |
769 | end Analyze_Return_Statement; | |
770 | ||
996ae0b0 RK |
771 | ----------------------------- |
772 | -- Analyze_Subprogram_Body -- | |
773 | ----------------------------- | |
774 | ||
775 | -- This procedure is called for regular subprogram bodies, generic bodies, | |
776 | -- and for subprogram stubs of both kinds. In the case of stubs, only the | |
777 | -- specification matters, and is used to create a proper declaration for | |
778 | -- the subprogram, or to perform conformance checks. | |
779 | ||
780 | procedure Analyze_Subprogram_Body (N : Node_Id) is | |
fbf5a39b AC |
781 | Loc : constant Source_Ptr := Sloc (N); |
782 | Body_Spec : constant Node_Id := Specification (N); | |
783 | Body_Id : Entity_Id := Defining_Entity (Body_Spec); | |
784 | Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id); | |
785 | Body_Deleted : constant Boolean := False; | |
996ae0b0 | 786 | |
0868e09c RD |
787 | HSS : Node_Id; |
788 | Spec_Id : Entity_Id; | |
789 | Spec_Decl : Node_Id := Empty; | |
790 | Last_Formal : Entity_Id := Empty; | |
791 | Conformant : Boolean; | |
792 | Missing_Ret : Boolean; | |
07fc65c4 | 793 | P_Ent : Entity_Id; |
996ae0b0 RK |
794 | |
795 | begin | |
796 | if Debug_Flag_C then | |
797 | Write_Str ("==== Compiling subprogram body "); | |
798 | Write_Name (Chars (Body_Id)); | |
799 | Write_Str (" from "); | |
0868e09c | 800 | Write_Location (Loc); |
996ae0b0 RK |
801 | Write_Eol; |
802 | end if; | |
803 | ||
804 | Trace_Scope (N, Body_Id, " Analyze subprogram"); | |
805 | ||
806 | -- Generic subprograms are handled separately. They always have | |
807 | -- a generic specification. Determine whether current scope has | |
808 | -- a previous declaration. | |
809 | ||
810 | -- If the subprogram body is defined within an instance of the | |
811 | -- same name, the instance appears as a package renaming, and | |
812 | -- will be hidden within the subprogram. | |
813 | ||
814 | if Present (Prev_Id) | |
815 | and then not Is_Overloadable (Prev_Id) | |
816 | and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration | |
817 | or else Comes_From_Source (Prev_Id)) | |
818 | then | |
fbf5a39b | 819 | if Is_Generic_Subprogram (Prev_Id) then |
996ae0b0 RK |
820 | Spec_Id := Prev_Id; |
821 | Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id)); | |
822 | Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id)); | |
823 | ||
824 | Analyze_Generic_Subprogram_Body (N, Spec_Id); | |
825 | return; | |
826 | ||
827 | else | |
828 | -- Previous entity conflicts with subprogram name. | |
829 | -- Attempting to enter name will post error. | |
830 | ||
831 | Enter_Name (Body_Id); | |
832 | return; | |
833 | end if; | |
834 | ||
835 | -- Non-generic case, find the subprogram declaration, if one was | |
836 | -- seen, or enter new overloaded entity in the current scope. | |
837 | -- If the current_entity is the body_id itself, the unit is being | |
838 | -- analyzed as part of the context of one of its subunits. No need | |
839 | -- to redo the analysis. | |
840 | ||
841 | elsif Prev_Id = Body_Id | |
842 | and then Has_Completion (Body_Id) | |
843 | then | |
844 | return; | |
845 | ||
846 | else | |
fbf5a39b | 847 | Body_Id := Analyze_Subprogram_Specification (Body_Spec); |
996ae0b0 RK |
848 | |
849 | if Nkind (N) = N_Subprogram_Body_Stub | |
850 | or else No (Corresponding_Spec (N)) | |
851 | then | |
852 | Spec_Id := Find_Corresponding_Spec (N); | |
853 | ||
854 | -- If this is a duplicate body, no point in analyzing it | |
855 | ||
856 | if Error_Posted (N) then | |
857 | return; | |
858 | end if; | |
859 | ||
860 | -- A subprogram body should cause freezing of its own | |
861 | -- declaration, but if there was no previous explicit | |
862 | -- declaration, then the subprogram will get frozen too | |
863 | -- late (there may be code within the body that depends | |
864 | -- on the subprogram having been frozen, such as uses of | |
865 | -- extra formals), so we force it to be frozen here. | |
866 | -- Same holds if the body and the spec are compilation units. | |
867 | ||
868 | if No (Spec_Id) then | |
869 | Freeze_Before (N, Body_Id); | |
870 | ||
871 | elsif Nkind (Parent (N)) = N_Compilation_Unit then | |
872 | Freeze_Before (N, Spec_Id); | |
873 | end if; | |
874 | else | |
875 | Spec_Id := Corresponding_Spec (N); | |
876 | end if; | |
877 | end if; | |
878 | ||
07fc65c4 GB |
879 | -- Do not inline any subprogram that contains nested subprograms, |
880 | -- since the backend inlining circuit seems to generate uninitialized | |
881 | -- references in this case. We know this happens in the case of front | |
882 | -- end ZCX support, but it also appears it can happen in other cases | |
883 | -- as well. The backend often rejects attempts to inline in the case | |
884 | -- of nested procedures anyway, so little if anything is lost by this. | |
885 | ||
886 | -- Do not do this test if errors have been detected, because in some | |
887 | -- error cases, this code blows up, and we don't need it anyway if | |
888 | -- there have been errors, since we won't get to the linker anyway. | |
889 | ||
890 | if Serious_Errors_Detected = 0 then | |
891 | P_Ent := Body_Id; | |
892 | loop | |
893 | P_Ent := Scope (P_Ent); | |
894 | exit when No (P_Ent) or else P_Ent = Standard_Standard; | |
895 | ||
fbf5a39b | 896 | if Is_Subprogram (P_Ent) then |
07fc65c4 GB |
897 | Set_Is_Inlined (P_Ent, False); |
898 | ||
899 | if Comes_From_Source (P_Ent) | |
07fc65c4 GB |
900 | and then Has_Pragma_Inline (P_Ent) |
901 | then | |
fbf5a39b AC |
902 | Cannot_Inline |
903 | ("cannot inline& (nested subprogram)?", | |
904 | N, P_Ent); | |
07fc65c4 GB |
905 | end if; |
906 | end if; | |
907 | end loop; | |
908 | end if; | |
909 | ||
910 | -- Case of fully private operation in the body of the protected type. | |
911 | -- We must create a declaration for the subprogram, in order to attach | |
912 | -- the protected subprogram that will be used in internal calls. | |
913 | ||
996ae0b0 RK |
914 | if No (Spec_Id) |
915 | and then Comes_From_Source (N) | |
916 | and then Is_Protected_Type (Current_Scope) | |
917 | then | |
996ae0b0 | 918 | declare |
996ae0b0 RK |
919 | Decl : Node_Id; |
920 | Plist : List_Id; | |
921 | Formal : Entity_Id; | |
922 | New_Spec : Node_Id; | |
923 | ||
924 | begin | |
925 | Formal := First_Formal (Body_Id); | |
926 | ||
927 | -- The protected operation always has at least one formal, | |
928 | -- namely the object itself, but it is only placed in the | |
929 | -- parameter list if expansion is enabled. | |
930 | ||
931 | if Present (Formal) | |
932 | or else Expander_Active | |
933 | then | |
934 | Plist := New_List; | |
935 | ||
936 | else | |
937 | Plist := No_List; | |
938 | end if; | |
939 | ||
940 | while Present (Formal) loop | |
941 | Append | |
942 | (Make_Parameter_Specification (Loc, | |
943 | Defining_Identifier => | |
944 | Make_Defining_Identifier (Sloc (Formal), | |
945 | Chars => Chars (Formal)), | |
946 | In_Present => In_Present (Parent (Formal)), | |
947 | Out_Present => Out_Present (Parent (Formal)), | |
948 | Parameter_Type => | |
949 | New_Reference_To (Etype (Formal), Loc), | |
950 | Expression => | |
951 | New_Copy_Tree (Expression (Parent (Formal)))), | |
952 | Plist); | |
953 | ||
954 | Next_Formal (Formal); | |
955 | end loop; | |
956 | ||
957 | if Nkind (Body_Spec) = N_Procedure_Specification then | |
958 | New_Spec := | |
959 | Make_Procedure_Specification (Loc, | |
960 | Defining_Unit_Name => | |
961 | Make_Defining_Identifier (Sloc (Body_Id), | |
962 | Chars => Chars (Body_Id)), | |
963 | Parameter_Specifications => Plist); | |
964 | else | |
965 | New_Spec := | |
966 | Make_Function_Specification (Loc, | |
967 | Defining_Unit_Name => | |
968 | Make_Defining_Identifier (Sloc (Body_Id), | |
969 | Chars => Chars (Body_Id)), | |
970 | Parameter_Specifications => Plist, | |
971 | Subtype_Mark => New_Occurrence_Of (Etype (Body_Id), Loc)); | |
972 | end if; | |
973 | ||
974 | Decl := | |
975 | Make_Subprogram_Declaration (Loc, | |
976 | Specification => New_Spec); | |
977 | Insert_Before (N, Decl); | |
978 | Analyze (Decl); | |
979 | Spec_Id := Defining_Unit_Name (New_Spec); | |
980 | Set_Has_Completion (Spec_Id); | |
981 | Set_Convention (Spec_Id, Convention_Protected); | |
982 | end; | |
983 | ||
984 | elsif Present (Spec_Id) then | |
985 | Spec_Decl := Unit_Declaration_Node (Spec_Id); | |
986 | end if; | |
987 | ||
988 | -- Place subprogram on scope stack, and make formals visible. If there | |
989 | -- is a spec, the visible entity remains that of the spec. | |
990 | ||
991 | if Present (Spec_Id) then | |
07fc65c4 | 992 | Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False); |
fbf5a39b AC |
993 | if Style_Check then |
994 | Style.Check_Identifier (Body_Id, Spec_Id); | |
995 | end if; | |
996ae0b0 RK |
996 | |
997 | Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id)); | |
998 | Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id)); | |
999 | ||
1000 | if Is_Abstract (Spec_Id) then | |
1001 | Error_Msg_N ("an abstract subprogram cannot have a body", N); | |
1002 | return; | |
1003 | else | |
1004 | Set_Convention (Body_Id, Convention (Spec_Id)); | |
1005 | Set_Has_Completion (Spec_Id); | |
1006 | ||
1007 | if Is_Protected_Type (Scope (Spec_Id)) then | |
1008 | Set_Privals_Chain (Spec_Id, New_Elmt_List); | |
1009 | end if; | |
1010 | ||
1011 | -- If this is a body generated for a renaming, do not check for | |
1012 | -- full conformance. The check is redundant, because the spec of | |
1013 | -- the body is a copy of the spec in the renaming declaration, | |
1014 | -- and the test can lead to spurious errors on nested defaults. | |
1015 | ||
1016 | if Present (Spec_Decl) | |
996ae0b0 | 1017 | and then not Comes_From_Source (N) |
93a81b02 GB |
1018 | and then |
1019 | (Nkind (Original_Node (Spec_Decl)) = | |
d2f97d3e GB |
1020 | N_Subprogram_Renaming_Declaration |
1021 | or else (Present (Corresponding_Body (Spec_Decl)) | |
1022 | and then | |
1023 | Nkind (Unit_Declaration_Node | |
1024 | (Corresponding_Body (Spec_Decl))) = | |
1025 | N_Subprogram_Renaming_Declaration)) | |
996ae0b0 RK |
1026 | then |
1027 | Conformant := True; | |
1028 | else | |
1029 | Check_Conformance | |
1030 | (Body_Id, Spec_Id, | |
1031 | Fully_Conformant, True, Conformant, Body_Id); | |
1032 | end if; | |
1033 | ||
1034 | -- If the body is not fully conformant, we have to decide if we | |
1035 | -- should analyze it or not. If it has a really messed up profile | |
1036 | -- then we probably should not analyze it, since we will get too | |
1037 | -- many bogus messages. | |
1038 | ||
1039 | -- Our decision is to go ahead in the non-fully conformant case | |
1040 | -- only if it is at least mode conformant with the spec. Note | |
1041 | -- that the call to Check_Fully_Conformant has issued the proper | |
1042 | -- error messages to complain about the lack of conformance. | |
1043 | ||
1044 | if not Conformant | |
1045 | and then not Mode_Conformant (Body_Id, Spec_Id) | |
1046 | then | |
1047 | return; | |
1048 | end if; | |
1049 | end if; | |
1050 | ||
996ae0b0 | 1051 | if Spec_Id /= Body_Id then |
fbf5a39b | 1052 | Reference_Body_Formals (Spec_Id, Body_Id); |
996ae0b0 RK |
1053 | end if; |
1054 | ||
1055 | if Nkind (N) /= N_Subprogram_Body_Stub then | |
1056 | Set_Corresponding_Spec (N, Spec_Id); | |
1057 | Install_Formals (Spec_Id); | |
1058 | Last_Formal := Last_Entity (Spec_Id); | |
1059 | New_Scope (Spec_Id); | |
1060 | ||
1061 | -- Make sure that the subprogram is immediately visible. For | |
1062 | -- child units that have no separate spec this is indispensable. | |
1063 | -- Otherwise it is safe albeit redundant. | |
1064 | ||
1065 | Set_Is_Immediately_Visible (Spec_Id); | |
1066 | end if; | |
1067 | ||
1068 | Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id); | |
1069 | Set_Ekind (Body_Id, E_Subprogram_Body); | |
1070 | Set_Scope (Body_Id, Scope (Spec_Id)); | |
1071 | ||
1072 | -- Case of subprogram body with no previous spec | |
1073 | ||
1074 | else | |
1075 | if Style_Check | |
1076 | and then Comes_From_Source (Body_Id) | |
1077 | and then not Suppress_Style_Checks (Body_Id) | |
1078 | and then not In_Instance | |
1079 | then | |
1080 | Style.Body_With_No_Spec (N); | |
1081 | end if; | |
1082 | ||
1083 | New_Overloaded_Entity (Body_Id); | |
1084 | ||
1085 | if Nkind (N) /= N_Subprogram_Body_Stub then | |
1086 | Set_Acts_As_Spec (N); | |
1087 | Generate_Definition (Body_Id); | |
fbf5a39b AC |
1088 | Generate_Reference |
1089 | (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True); | |
1090 | Generate_Reference_To_Formals (Body_Id); | |
996ae0b0 RK |
1091 | Install_Formals (Body_Id); |
1092 | New_Scope (Body_Id); | |
1093 | end if; | |
1094 | end if; | |
1095 | ||
1096 | -- If this is the proper body of a stub, we must verify that the stub | |
1097 | -- conforms to the body, and to the previous spec if one was present. | |
1098 | -- we know already that the body conforms to that spec. This test is | |
1099 | -- only required for subprograms that come from source. | |
1100 | ||
1101 | if Nkind (Parent (N)) = N_Subunit | |
1102 | and then Comes_From_Source (N) | |
1103 | and then not Error_Posted (Body_Id) | |
1104 | then | |
1105 | declare | |
fbf5a39b AC |
1106 | Old_Id : constant Entity_Id := |
1107 | Defining_Entity | |
1108 | (Specification (Corresponding_Stub (Parent (N)))); | |
1109 | ||
996ae0b0 | 1110 | Conformant : Boolean := False; |
996ae0b0 RK |
1111 | |
1112 | begin | |
1113 | if No (Spec_Id) then | |
1114 | Check_Fully_Conformant (Body_Id, Old_Id); | |
1115 | ||
1116 | else | |
1117 | Check_Conformance | |
1118 | (Body_Id, Old_Id, Fully_Conformant, False, Conformant); | |
1119 | ||
1120 | if not Conformant then | |
1121 | ||
1122 | -- The stub was taken to be a new declaration. Indicate | |
1123 | -- that it lacks a body. | |
1124 | ||
1125 | Set_Has_Completion (Old_Id, False); | |
1126 | end if; | |
1127 | end if; | |
1128 | end; | |
1129 | end if; | |
1130 | ||
1131 | Set_Has_Completion (Body_Id); | |
1132 | Check_Eliminated (Body_Id); | |
1133 | ||
1134 | if Nkind (N) = N_Subprogram_Body_Stub then | |
1135 | return; | |
1136 | ||
1137 | elsif Present (Spec_Id) | |
1138 | and then Expander_Active | |
07fc65c4 GB |
1139 | and then (Is_Always_Inlined (Spec_Id) |
1140 | or else (Has_Pragma_Inline (Spec_Id) | |
1141 | and then | |
fbf5a39b AC |
1142 | (Front_End_Inlining |
1143 | or else Configurable_Run_Time_Mode))) | |
996ae0b0 RK |
1144 | then |
1145 | if Build_Body_To_Inline (N, Spec_Id, Copy_Separate_Tree (N)) then | |
1146 | null; | |
1147 | end if; | |
1148 | end if; | |
1149 | ||
0868e09c | 1150 | -- Now we can go on to analyze the body |
996ae0b0 RK |
1151 | |
1152 | HSS := Handled_Statement_Sequence (N); | |
1153 | Set_Actual_Subtypes (N, Current_Scope); | |
1154 | Analyze_Declarations (Declarations (N)); | |
1155 | Check_Completion; | |
1156 | Analyze (HSS); | |
07fc65c4 | 1157 | Process_End_Label (HSS, 't', Current_Scope); |
996ae0b0 RK |
1158 | End_Scope; |
1159 | Check_Subprogram_Order (N); | |
1160 | ||
1161 | -- If we have a separate spec, then the analysis of the declarations | |
1162 | -- caused the entities in the body to be chained to the spec id, but | |
1163 | -- we want them chained to the body id. Only the formal parameters | |
1164 | -- end up chained to the spec id in this case. | |
1165 | ||
1166 | if Present (Spec_Id) then | |
1167 | ||
1168 | -- If a parent unit is categorized, the context of a subunit | |
1169 | -- must conform to the categorization. Conversely, if a child | |
1170 | -- unit is categorized, the parents themselves must conform. | |
1171 | ||
1172 | if Nkind (Parent (N)) = N_Subunit then | |
1173 | Validate_Categorization_Dependency (N, Spec_Id); | |
1174 | ||
1175 | elsif Is_Child_Unit (Spec_Id) then | |
1176 | Validate_Categorization_Dependency | |
1177 | (Unit_Declaration_Node (Spec_Id), Spec_Id); | |
1178 | end if; | |
1179 | ||
1180 | if Present (Last_Formal) then | |
1181 | Set_Next_Entity | |
1182 | (Last_Entity (Body_Id), Next_Entity (Last_Formal)); | |
1183 | Set_Next_Entity (Last_Formal, Empty); | |
1184 | Set_Last_Entity (Body_Id, Last_Entity (Spec_Id)); | |
1185 | Set_Last_Entity (Spec_Id, Last_Formal); | |
1186 | ||
1187 | else | |
1188 | Set_First_Entity (Body_Id, First_Entity (Spec_Id)); | |
1189 | Set_Last_Entity (Body_Id, Last_Entity (Spec_Id)); | |
1190 | Set_First_Entity (Spec_Id, Empty); | |
1191 | Set_Last_Entity (Spec_Id, Empty); | |
1192 | end if; | |
1193 | end if; | |
1194 | ||
1195 | -- If function, check return statements | |
1196 | ||
1197 | if Nkind (Body_Spec) = N_Function_Specification then | |
1198 | declare | |
1199 | Id : Entity_Id; | |
1200 | ||
1201 | begin | |
1202 | if Present (Spec_Id) then | |
1203 | Id := Spec_Id; | |
1204 | else | |
1205 | Id := Body_Id; | |
1206 | end if; | |
1207 | ||
1208 | if Return_Present (Id) then | |
1209 | Check_Returns (HSS, 'F', Missing_Ret); | |
1210 | ||
1211 | if Missing_Ret then | |
1212 | Set_Has_Missing_Return (Id); | |
1213 | end if; | |
1214 | ||
0868e09c RD |
1215 | elsif not Is_Machine_Code_Subprogram (Id) |
1216 | and then not Body_Deleted | |
1217 | then | |
996ae0b0 RK |
1218 | Error_Msg_N ("missing RETURN statement in function body", N); |
1219 | end if; | |
1220 | end; | |
1221 | ||
1222 | -- If procedure with No_Return, check returns | |
1223 | ||
1224 | elsif Nkind (Body_Spec) = N_Procedure_Specification | |
1225 | and then Present (Spec_Id) | |
1226 | and then No_Return (Spec_Id) | |
1227 | then | |
1228 | Check_Returns (HSS, 'P', Missing_Ret); | |
1229 | end if; | |
1230 | ||
fbf5a39b AC |
1231 | -- Now we are going to check for variables that are never modified |
1232 | -- in the body of the procedure. We omit these checks if the first | |
1233 | -- statement of the procedure raises an exception. In particular | |
1234 | -- this deals with the common idiom of a stubbed function, which | |
1235 | -- might appear as something like | |
1236 | ||
1237 | -- function F (A : Integer) return Some_Type; | |
1238 | -- X : Some_Type; | |
1239 | -- begin | |
1240 | -- raise Program_Error; | |
1241 | -- return X; | |
1242 | -- end F; | |
1243 | ||
1244 | -- Here the purpose of X is simply to satisfy the (annoying) | |
1245 | -- requirement in Ada that there be at least one return, and | |
1246 | -- we certainly do not want to go posting warnings on X that | |
1247 | -- it is not initialized! | |
996ae0b0 RK |
1248 | |
1249 | declare | |
1250 | Stm : Node_Id := First (Statements (HSS)); | |
1251 | ||
1252 | begin | |
fbf5a39b AC |
1253 | -- Skip an initial label (for one thing this occurs when we |
1254 | -- are in front end ZCX mode, but in any case it is irrelevant). | |
1255 | ||
996ae0b0 RK |
1256 | if Nkind (Stm) = N_Label then |
1257 | Next (Stm); | |
1258 | end if; | |
1259 | ||
fbf5a39b AC |
1260 | -- Do the test on the original statement before expansion |
1261 | ||
1262 | declare | |
1263 | Ostm : constant Node_Id := Original_Node (Stm); | |
1264 | ||
1265 | begin | |
1266 | -- If explicit raise statement, return with no checks | |
1267 | ||
1268 | if Nkind (Ostm) = N_Raise_Statement then | |
1269 | return; | |
1270 | ||
1271 | -- Check for explicit call cases which likely raise an exception | |
1272 | ||
1273 | elsif Nkind (Ostm) = N_Procedure_Call_Statement then | |
1274 | if Is_Entity_Name (Name (Ostm)) then | |
1275 | declare | |
1276 | Ent : constant Entity_Id := Entity (Name (Ostm)); | |
1277 | ||
1278 | begin | |
1279 | -- If the procedure is marked No_Return, then likely it | |
1280 | -- raises an exception, but in any case it is not coming | |
1281 | -- back here, so no need to check beyond the call. | |
1282 | ||
1283 | if Ekind (Ent) = E_Procedure | |
1284 | and then No_Return (Ent) | |
1285 | then | |
1286 | return; | |
1287 | ||
1288 | -- If the procedure name is Raise_Exception, then also | |
1289 | -- assume that it raises an exception. The main target | |
1290 | -- here is Ada.Exceptions.Raise_Exception, but this name | |
1291 | -- is pretty evocative in any context! Note that the | |
1292 | -- procedure in Ada.Exceptions is not marked No_Return | |
1293 | -- because of the annoying case of the null exception Id. | |
1294 | ||
1295 | elsif Chars (Ent) = Name_Raise_Exception then | |
1296 | return; | |
1297 | end if; | |
1298 | end; | |
1299 | end if; | |
1300 | end if; | |
1301 | end; | |
996ae0b0 RK |
1302 | end; |
1303 | ||
1304 | -- Check for variables that are never modified | |
1305 | ||
1306 | declare | |
1307 | E1, E2 : Entity_Id; | |
1308 | ||
1309 | begin | |
fbf5a39b | 1310 | -- If there is a separate spec, then transfer Never_Set_In_Source |
996ae0b0 RK |
1311 | -- flags from out parameters to the corresponding entities in the |
1312 | -- body. The reason we do that is we want to post error flags on | |
1313 | -- the body entities, not the spec entities. | |
1314 | ||
1315 | if Present (Spec_Id) then | |
1316 | E1 := First_Entity (Spec_Id); | |
1317 | ||
1318 | while Present (E1) loop | |
1319 | if Ekind (E1) = E_Out_Parameter then | |
1320 | E2 := First_Entity (Body_Id); | |
fbf5a39b | 1321 | while Present (E2) loop |
996ae0b0 RK |
1322 | exit when Chars (E1) = Chars (E2); |
1323 | Next_Entity (E2); | |
1324 | end loop; | |
1325 | ||
fbf5a39b AC |
1326 | if Present (E2) then |
1327 | Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1)); | |
1328 | end if; | |
996ae0b0 RK |
1329 | end if; |
1330 | ||
1331 | Next_Entity (E1); | |
1332 | end loop; | |
1333 | end if; | |
1334 | ||
0868e09c RD |
1335 | -- Check references in body unless it was deleted. Note that the |
1336 | -- check of Body_Deleted here is not just for efficiency, it is | |
1337 | -- necessary to avoid junk warnings on formal parameters. | |
1338 | ||
1339 | if not Body_Deleted then | |
1340 | Check_References (Body_Id); | |
1341 | end if; | |
996ae0b0 RK |
1342 | end; |
1343 | end Analyze_Subprogram_Body; | |
1344 | ||
1345 | ------------------------------------ | |
1346 | -- Analyze_Subprogram_Declaration -- | |
1347 | ------------------------------------ | |
1348 | ||
1349 | procedure Analyze_Subprogram_Declaration (N : Node_Id) is | |
fbf5a39b AC |
1350 | Designator : constant Entity_Id := |
1351 | Analyze_Subprogram_Specification (Specification (N)); | |
1352 | Scop : constant Entity_Id := Current_Scope; | |
996ae0b0 RK |
1353 | |
1354 | -- Start of processing for Analyze_Subprogram_Declaration | |
1355 | ||
1356 | begin | |
1357 | Generate_Definition (Designator); | |
1358 | ||
1359 | -- Check for RCI unit subprogram declarations against in-lined | |
1360 | -- subprograms and subprograms having access parameter or limited | |
1361 | -- parameter without Read and Write (RM E.2.3(12-13)). | |
1362 | ||
1363 | Validate_RCI_Subprogram_Declaration (N); | |
1364 | ||
1365 | Trace_Scope | |
1366 | (N, | |
1367 | Defining_Entity (N), | |
1368 | " Analyze subprogram spec. "); | |
1369 | ||
1370 | if Debug_Flag_C then | |
1371 | Write_Str ("==== Compiling subprogram spec "); | |
1372 | Write_Name (Chars (Designator)); | |
1373 | Write_Str (" from "); | |
1374 | Write_Location (Sloc (N)); | |
1375 | Write_Eol; | |
1376 | end if; | |
1377 | ||
1378 | New_Overloaded_Entity (Designator); | |
1379 | Check_Delayed_Subprogram (Designator); | |
fbf5a39b AC |
1380 | |
1381 | -- What is the following code for, it used to be | |
1382 | ||
1383 | -- ??? Set_Suppress_Elaboration_Checks | |
1384 | -- ??? (Designator, Elaboration_Checks_Suppressed (Designator)); | |
1385 | ||
1386 | -- The following seems equivalent, but a bit dubious | |
1387 | ||
1388 | if Elaboration_Checks_Suppressed (Designator) then | |
1389 | Set_Kill_Elaboration_Checks (Designator); | |
1390 | end if; | |
996ae0b0 RK |
1391 | |
1392 | if Scop /= Standard_Standard | |
1393 | and then not Is_Child_Unit (Designator) | |
1394 | then | |
fbf5a39b | 1395 | Set_Categorization_From_Scope (Designator, Scop); |
996ae0b0 RK |
1396 | else |
1397 | -- For a compilation unit, check for library-unit pragmas. | |
1398 | ||
1399 | New_Scope (Designator); | |
1400 | Set_Categorization_From_Pragmas (N); | |
1401 | Validate_Categorization_Dependency (N, Designator); | |
1402 | Pop_Scope; | |
1403 | end if; | |
1404 | ||
1405 | -- For a compilation unit, set body required. This flag will only be | |
1406 | -- reset if a valid Import or Interface pragma is processed later on. | |
1407 | ||
1408 | if Nkind (Parent (N)) = N_Compilation_Unit then | |
1409 | Set_Body_Required (Parent (N), True); | |
1410 | end if; | |
1411 | ||
fbf5a39b | 1412 | Generate_Reference_To_Formals (Designator); |
996ae0b0 | 1413 | Check_Eliminated (Designator); |
fbf5a39b AC |
1414 | |
1415 | if Comes_From_Source (N) | |
1416 | and then Is_List_Member (N) | |
1417 | then | |
1418 | Check_Overriding_Operation (N, Designator); | |
1419 | end if; | |
1420 | ||
996ae0b0 RK |
1421 | end Analyze_Subprogram_Declaration; |
1422 | ||
fbf5a39b AC |
1423 | -------------------------------------- |
1424 | -- Analyze_Subprogram_Specification -- | |
1425 | -------------------------------------- | |
1426 | ||
1427 | -- Reminder: N here really is a subprogram specification (not a subprogram | |
1428 | -- declaration). This procedure is called to analyze the specification in | |
1429 | -- both subprogram bodies and subprogram declarations (specs). | |
1430 | ||
1431 | function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is | |
1432 | Designator : constant Entity_Id := Defining_Entity (N); | |
1433 | Formals : constant List_Id := Parameter_Specifications (N); | |
1434 | Typ : Entity_Id; | |
1435 | ||
1436 | begin | |
1437 | Generate_Definition (Designator); | |
1438 | ||
1439 | if Nkind (N) = N_Function_Specification then | |
1440 | Set_Ekind (Designator, E_Function); | |
1441 | Set_Mechanism (Designator, Default_Mechanism); | |
1442 | ||
1443 | if Subtype_Mark (N) /= Error then | |
1444 | Find_Type (Subtype_Mark (N)); | |
1445 | Typ := Entity (Subtype_Mark (N)); | |
1446 | Set_Etype (Designator, Typ); | |
1447 | ||
1448 | if Ekind (Typ) = E_Incomplete_Type | |
1449 | or else (Is_Class_Wide_Type (Typ) | |
1450 | and then | |
1451 | Ekind (Root_Type (Typ)) = E_Incomplete_Type) | |
1452 | then | |
1453 | Error_Msg_N | |
1454 | ("invalid use of incomplete type", Subtype_Mark (N)); | |
1455 | end if; | |
1456 | ||
1457 | else | |
1458 | Set_Etype (Designator, Any_Type); | |
1459 | end if; | |
1460 | ||
1461 | else | |
1462 | Set_Ekind (Designator, E_Procedure); | |
1463 | Set_Etype (Designator, Standard_Void_Type); | |
1464 | end if; | |
1465 | ||
1466 | if Present (Formals) then | |
1467 | Set_Scope (Designator, Current_Scope); | |
1468 | New_Scope (Designator); | |
1469 | Process_Formals (Formals, N); | |
1470 | End_Scope; | |
1471 | end if; | |
1472 | ||
1473 | if Nkind (N) = N_Function_Specification then | |
1474 | if Nkind (Designator) = N_Defining_Operator_Symbol then | |
1475 | Valid_Operator_Definition (Designator); | |
1476 | end if; | |
1477 | ||
1478 | May_Need_Actuals (Designator); | |
1479 | ||
1480 | if Is_Abstract (Etype (Designator)) | |
1481 | and then Nkind (Parent (N)) /= N_Abstract_Subprogram_Declaration | |
1482 | then | |
1483 | Error_Msg_N | |
1484 | ("function that returns abstract type must be abstract", N); | |
1485 | end if; | |
1486 | end if; | |
1487 | ||
1488 | return Designator; | |
1489 | end Analyze_Subprogram_Specification; | |
1490 | ||
996ae0b0 RK |
1491 | -------------------------- |
1492 | -- Build_Body_To_Inline -- | |
1493 | -------------------------- | |
1494 | ||
1495 | function Build_Body_To_Inline | |
1496 | (N : Node_Id; | |
1497 | Subp : Entity_Id; | |
fbf5a39b AC |
1498 | Orig_Body : Node_Id) |
1499 | return Boolean | |
996ae0b0 RK |
1500 | is |
1501 | Decl : constant Node_Id := Unit_Declaration_Node (Subp); | |
1502 | Original_Body : Node_Id; | |
1503 | Body_To_Analyze : Node_Id; | |
1504 | Max_Size : constant := 10; | |
1505 | Stat_Count : Integer := 0; | |
1506 | ||
1507 | function Has_Excluded_Declaration (Decls : List_Id) return Boolean; | |
1508 | -- Check for declarations that make inlining not worthwhile. | |
1509 | ||
1510 | function Has_Excluded_Statement (Stats : List_Id) return Boolean; | |
1511 | -- Check for statements that make inlining not worthwhile: any | |
1512 | -- tasking statement, nested at any level. Keep track of total | |
1513 | -- number of elementary statements, as a measure of acceptable size. | |
1514 | ||
1515 | function Has_Pending_Instantiation return Boolean; | |
1516 | -- If some enclosing body contains instantiations that appear before | |
1517 | -- the corresponding generic body, the enclosing body has a freeze node | |
1518 | -- so that it can be elaborated after the generic itself. This might | |
1519 | -- conflict with subsequent inlinings, so that it is unsafe to try to | |
1520 | -- inline in such a case. | |
1521 | ||
fbf5a39b AC |
1522 | procedure Remove_Pragmas; |
1523 | -- A pragma Unreferenced that mentions a formal parameter has no | |
1524 | -- meaning when the body is inlined and the formals are rewritten. | |
1525 | -- Remove it from body to inline. The analysis of the non-inlined | |
1526 | -- body will handle the pragma properly. | |
996ae0b0 RK |
1527 | |
1528 | ------------------------------ | |
1529 | -- Has_Excluded_Declaration -- | |
1530 | ------------------------------ | |
1531 | ||
1532 | function Has_Excluded_Declaration (Decls : List_Id) return Boolean is | |
1533 | D : Node_Id; | |
1534 | ||
fbf5a39b AC |
1535 | function Is_Unchecked_Conversion (D : Node_Id) return Boolean; |
1536 | -- Nested subprograms make a given body ineligible for inlining, | |
1537 | -- but we make an exception for instantiations of unchecked | |
1538 | -- conversion. The body has not been analyzed yet, so we check | |
1539 | -- the name, and verify that the visible entity with that name is | |
1540 | -- the predefined unit. | |
1541 | ||
1542 | function Is_Unchecked_Conversion (D : Node_Id) return Boolean is | |
1543 | Id : constant Node_Id := Name (D); | |
1544 | Conv : Entity_Id; | |
1545 | ||
1546 | begin | |
1547 | if Nkind (Id) = N_Identifier | |
1548 | and then Chars (Id) = Name_Unchecked_Conversion | |
1549 | then | |
1550 | Conv := Current_Entity (Id); | |
1551 | ||
1552 | elsif Nkind (Id) = N_Selected_Component | |
1553 | and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion | |
1554 | then | |
1555 | Conv := Current_Entity (Selector_Name (Id)); | |
1556 | ||
1557 | else | |
1558 | return False; | |
1559 | end if; | |
1560 | ||
1561 | return | |
1562 | Present (Conv) | |
1563 | and then Scope (Conv) = Standard_Standard | |
1564 | and then Is_Intrinsic_Subprogram (Conv); | |
1565 | end Is_Unchecked_Conversion; | |
1566 | ||
1567 | -- Start of processing for Has_Excluded_Declaration | |
1568 | ||
996ae0b0 RK |
1569 | begin |
1570 | D := First (Decls); | |
1571 | ||
1572 | while Present (D) loop | |
fbf5a39b AC |
1573 | if (Nkind (D) = N_Function_Instantiation |
1574 | and then not Is_Unchecked_Conversion (D)) | |
996ae0b0 RK |
1575 | or else Nkind (D) = N_Protected_Type_Declaration |
1576 | or else Nkind (D) = N_Package_Declaration | |
1577 | or else Nkind (D) = N_Package_Instantiation | |
1578 | or else Nkind (D) = N_Subprogram_Body | |
1579 | or else Nkind (D) = N_Procedure_Instantiation | |
1580 | or else Nkind (D) = N_Task_Type_Declaration | |
1581 | then | |
1582 | Cannot_Inline | |
fbf5a39b | 1583 | ("cannot inline & (non-allowed declaration)?", D, Subp); |
996ae0b0 RK |
1584 | return True; |
1585 | end if; | |
1586 | ||
1587 | Next (D); | |
1588 | end loop; | |
1589 | ||
1590 | return False; | |
996ae0b0 RK |
1591 | end Has_Excluded_Declaration; |
1592 | ||
1593 | ---------------------------- | |
1594 | -- Has_Excluded_Statement -- | |
1595 | ---------------------------- | |
1596 | ||
1597 | function Has_Excluded_Statement (Stats : List_Id) return Boolean is | |
1598 | S : Node_Id; | |
1599 | E : Node_Id; | |
1600 | ||
1601 | begin | |
1602 | S := First (Stats); | |
1603 | ||
1604 | while Present (S) loop | |
1605 | Stat_Count := Stat_Count + 1; | |
1606 | ||
1607 | if Nkind (S) = N_Abort_Statement | |
1608 | or else Nkind (S) = N_Asynchronous_Select | |
1609 | or else Nkind (S) = N_Conditional_Entry_Call | |
1610 | or else Nkind (S) = N_Delay_Relative_Statement | |
1611 | or else Nkind (S) = N_Delay_Until_Statement | |
1612 | or else Nkind (S) = N_Selective_Accept | |
1613 | or else Nkind (S) = N_Timed_Entry_Call | |
1614 | then | |
1615 | Cannot_Inline | |
fbf5a39b | 1616 | ("cannot inline & (non-allowed statement)?", S, Subp); |
996ae0b0 RK |
1617 | return True; |
1618 | ||
1619 | elsif Nkind (S) = N_Block_Statement then | |
1620 | if Present (Declarations (S)) | |
1621 | and then Has_Excluded_Declaration (Declarations (S)) | |
1622 | then | |
1623 | return True; | |
1624 | ||
1625 | elsif Present (Handled_Statement_Sequence (S)) | |
1626 | and then | |
1627 | (Present | |
1628 | (Exception_Handlers (Handled_Statement_Sequence (S))) | |
1629 | or else | |
1630 | Has_Excluded_Statement | |
1631 | (Statements (Handled_Statement_Sequence (S)))) | |
1632 | then | |
1633 | return True; | |
1634 | end if; | |
1635 | ||
1636 | elsif Nkind (S) = N_Case_Statement then | |
1637 | E := First (Alternatives (S)); | |
1638 | ||
1639 | while Present (E) loop | |
1640 | if Has_Excluded_Statement (Statements (E)) then | |
1641 | return True; | |
1642 | end if; | |
1643 | ||
1644 | Next (E); | |
1645 | end loop; | |
1646 | ||
1647 | elsif Nkind (S) = N_If_Statement then | |
1648 | if Has_Excluded_Statement (Then_Statements (S)) then | |
1649 | return True; | |
1650 | end if; | |
1651 | ||
1652 | if Present (Elsif_Parts (S)) then | |
1653 | E := First (Elsif_Parts (S)); | |
1654 | ||
1655 | while Present (E) loop | |
1656 | if Has_Excluded_Statement (Then_Statements (E)) then | |
1657 | return True; | |
1658 | end if; | |
1659 | Next (E); | |
1660 | end loop; | |
1661 | end if; | |
1662 | ||
1663 | if Present (Else_Statements (S)) | |
1664 | and then Has_Excluded_Statement (Else_Statements (S)) | |
1665 | then | |
1666 | return True; | |
1667 | end if; | |
1668 | ||
1669 | elsif Nkind (S) = N_Loop_Statement | |
1670 | and then Has_Excluded_Statement (Statements (S)) | |
1671 | then | |
1672 | return True; | |
1673 | end if; | |
1674 | ||
1675 | Next (S); | |
1676 | end loop; | |
1677 | ||
1678 | return False; | |
1679 | end Has_Excluded_Statement; | |
1680 | ||
1681 | ------------------------------- | |
1682 | -- Has_Pending_Instantiation -- | |
1683 | ------------------------------- | |
1684 | ||
1685 | function Has_Pending_Instantiation return Boolean is | |
1686 | S : Entity_Id := Current_Scope; | |
1687 | ||
1688 | begin | |
1689 | while Present (S) loop | |
1690 | if Is_Compilation_Unit (S) | |
1691 | or else Is_Child_Unit (S) | |
1692 | then | |
1693 | return False; | |
1694 | elsif Ekind (S) = E_Package | |
1695 | and then Has_Forward_Instantiation (S) | |
1696 | then | |
1697 | return True; | |
1698 | end if; | |
1699 | ||
1700 | S := Scope (S); | |
1701 | end loop; | |
1702 | ||
1703 | return False; | |
1704 | end Has_Pending_Instantiation; | |
1705 | ||
fbf5a39b AC |
1706 | -------------------- |
1707 | -- Remove_Pragmas -- | |
1708 | -------------------- | |
1709 | ||
1710 | procedure Remove_Pragmas is | |
1711 | Decl : Node_Id; | |
1712 | Nxt : Node_Id; | |
1713 | ||
1714 | begin | |
1715 | Decl := First (Declarations (Body_To_Analyze)); | |
1716 | while Present (Decl) loop | |
1717 | Nxt := Next (Decl); | |
1718 | ||
1719 | if Nkind (Decl) = N_Pragma | |
1720 | and then Chars (Decl) = Name_Unreferenced | |
1721 | then | |
1722 | Remove (Decl); | |
1723 | end if; | |
1724 | ||
1725 | Decl := Nxt; | |
1726 | end loop; | |
1727 | end Remove_Pragmas; | |
1728 | ||
996ae0b0 RK |
1729 | -- Start of processing for Build_Body_To_Inline |
1730 | ||
1731 | begin | |
1732 | if Nkind (Decl) = N_Subprogram_Declaration | |
1733 | and then Present (Body_To_Inline (Decl)) | |
1734 | then | |
1735 | return True; -- Done already. | |
1736 | ||
1737 | -- Functions that return unconstrained composite types will require | |
1738 | -- secondary stack handling, and cannot currently be inlined. | |
1739 | ||
1740 | elsif Ekind (Subp) = E_Function | |
1741 | and then not Is_Scalar_Type (Etype (Subp)) | |
1742 | and then not Is_Access_Type (Etype (Subp)) | |
1743 | and then not Is_Constrained (Etype (Subp)) | |
1744 | then | |
1745 | Cannot_Inline | |
fbf5a39b | 1746 | ("cannot inline & (unconstrained return type)?", N, Subp); |
996ae0b0 RK |
1747 | return False; |
1748 | end if; | |
1749 | ||
1750 | -- We need to capture references to the formals in order to substitute | |
1751 | -- the actuals at the point of inlining, i.e. instantiation. To treat | |
1752 | -- the formals as globals to the body to inline, we nest it within | |
1753 | -- a dummy parameterless subprogram, declared within the real one. | |
1754 | ||
1755 | Original_Body := Orig_Body; | |
1756 | ||
1757 | -- Within an instance, the current tree is already the result of | |
1758 | -- a generic copy, and not what we need for subsequent inlining. | |
1759 | -- We create the required body by doing an instantiating copy, to | |
1760 | -- obtain the proper partially analyzed tree. | |
1761 | ||
1762 | if In_Instance then | |
1763 | if No (Generic_Parent (Specification (N))) then | |
1764 | return False; | |
1765 | ||
1766 | elsif Is_Child_Unit (Scope (Current_Scope)) then | |
1767 | return False; | |
1768 | ||
1769 | elsif Scope (Current_Scope) = Cunit_Entity (Main_Unit) then | |
1770 | ||
1771 | -- compiling an instantiation. There is no point in generating | |
1772 | -- bodies to inline, because they will not be used. | |
1773 | ||
1774 | return False; | |
1775 | ||
1776 | else | |
1777 | Body_To_Analyze := | |
1778 | Copy_Generic_Node | |
1779 | (Generic_Parent (Specification (N)), Empty, | |
1780 | Instantiating => True); | |
1781 | end if; | |
fbf5a39b AC |
1782 | |
1783 | -- Case of not in an instance | |
1784 | ||
996ae0b0 RK |
1785 | else |
1786 | Body_To_Analyze := | |
1787 | Copy_Generic_Node (Original_Body, Empty, | |
1788 | Instantiating => False); | |
1789 | end if; | |
1790 | ||
1791 | Set_Parameter_Specifications (Specification (Original_Body), No_List); | |
1792 | Set_Defining_Unit_Name (Specification (Original_Body), | |
1793 | Make_Defining_Identifier (Sloc (N), New_Internal_Name ('S'))); | |
1794 | Set_Corresponding_Spec (Original_Body, Empty); | |
1795 | ||
1796 | if Ekind (Subp) = E_Function then | |
1797 | Set_Subtype_Mark (Specification (Original_Body), | |
1798 | New_Occurrence_Of (Etype (Subp), Sloc (N))); | |
1799 | end if; | |
1800 | ||
1801 | if Present (Declarations (Orig_Body)) | |
1802 | and then Has_Excluded_Declaration (Declarations (Orig_Body)) | |
1803 | then | |
1804 | return False; | |
1805 | end if; | |
1806 | ||
1807 | if Present (Handled_Statement_Sequence (N)) then | |
fbf5a39b AC |
1808 | if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then |
1809 | Cannot_Inline | |
1810 | ("cannot inline& (exception handler)?", | |
1811 | First (Exception_Handlers (Handled_Statement_Sequence (N))), | |
1812 | Subp); | |
996ae0b0 RK |
1813 | return False; |
1814 | elsif | |
1815 | Has_Excluded_Statement | |
1816 | (Statements (Handled_Statement_Sequence (N))) | |
1817 | then | |
1818 | return False; | |
1819 | end if; | |
1820 | end if; | |
1821 | ||
1822 | -- We do not inline a subprogram that is too large, unless it is | |
1823 | -- marked Inline_Always. This pragma does not suppress the other | |
1824 | -- checks on inlining (forbidden declarations, handlers, etc). | |
1825 | ||
1826 | if Stat_Count > Max_Size | |
1827 | and then not Is_Always_Inlined (Subp) | |
1828 | then | |
fbf5a39b | 1829 | Cannot_Inline ("cannot inline& (body too large)?", N, Subp); |
996ae0b0 RK |
1830 | return False; |
1831 | end if; | |
1832 | ||
1833 | if Has_Pending_Instantiation then | |
1834 | Cannot_Inline | |
fbf5a39b AC |
1835 | ("cannot inline& (forward instance within enclosing body)?", |
1836 | N, Subp); | |
996ae0b0 RK |
1837 | return False; |
1838 | end if; | |
1839 | ||
1840 | Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False); | |
1841 | ||
1842 | -- Set return type of function, which is also global and does not need | |
1843 | -- to be resolved. | |
1844 | ||
1845 | if Ekind (Subp) = E_Function then | |
1846 | Set_Subtype_Mark (Specification (Body_To_Analyze), | |
1847 | New_Occurrence_Of (Etype (Subp), Sloc (N))); | |
1848 | end if; | |
1849 | ||
1850 | if No (Declarations (N)) then | |
1851 | Set_Declarations (N, New_List (Body_To_Analyze)); | |
1852 | else | |
1853 | Append (Body_To_Analyze, Declarations (N)); | |
1854 | end if; | |
1855 | ||
1856 | Expander_Mode_Save_And_Set (False); | |
fbf5a39b | 1857 | Remove_Pragmas; |
996ae0b0 RK |
1858 | |
1859 | Analyze (Body_To_Analyze); | |
1860 | New_Scope (Defining_Entity (Body_To_Analyze)); | |
1861 | Save_Global_References (Original_Body); | |
1862 | End_Scope; | |
1863 | Remove (Body_To_Analyze); | |
1864 | ||
1865 | Expander_Mode_Restore; | |
1866 | Set_Body_To_Inline (Decl, Original_Body); | |
fbf5a39b | 1867 | Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp)); |
996ae0b0 RK |
1868 | Set_Is_Inlined (Subp); |
1869 | return True; | |
996ae0b0 RK |
1870 | end Build_Body_To_Inline; |
1871 | ||
fbf5a39b AC |
1872 | ------------------- |
1873 | -- Cannot_Inline -- | |
1874 | ------------------- | |
1875 | ||
1876 | procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is | |
1877 | begin | |
1878 | -- Do not emit warning if this is a predefined unit which is not | |
1879 | -- the main unit. With validity checks enabled, some predefined | |
1880 | -- subprograms may contain nested subprograms and become ineligible | |
1881 | -- for inlining. | |
1882 | ||
1883 | if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp))) | |
1884 | and then not In_Extended_Main_Source_Unit (Subp) | |
1885 | then | |
1886 | null; | |
1887 | ||
1888 | elsif Is_Always_Inlined (Subp) then | |
1889 | Error_Msg_NE (Msg (1 .. Msg'Length - 1), N, Subp); | |
1890 | ||
1891 | elsif Ineffective_Inline_Warnings then | |
1892 | Error_Msg_NE (Msg, N, Subp); | |
1893 | end if; | |
1894 | end Cannot_Inline; | |
1895 | ||
996ae0b0 RK |
1896 | ----------------------- |
1897 | -- Check_Conformance -- | |
1898 | ----------------------- | |
1899 | ||
1900 | procedure Check_Conformance | |
1901 | (New_Id : Entity_Id; | |
1902 | Old_Id : Entity_Id; | |
1903 | Ctype : Conformance_Type; | |
1904 | Errmsg : Boolean; | |
1905 | Conforms : out Boolean; | |
1906 | Err_Loc : Node_Id := Empty; | |
1907 | Get_Inst : Boolean := False) | |
1908 | is | |
1909 | Old_Type : constant Entity_Id := Etype (Old_Id); | |
1910 | New_Type : constant Entity_Id := Etype (New_Id); | |
1911 | Old_Formal : Entity_Id; | |
1912 | New_Formal : Entity_Id; | |
1913 | ||
1914 | procedure Conformance_Error (Msg : String; N : Node_Id := New_Id); | |
1915 | -- Post error message for conformance error on given node. | |
1916 | -- Two messages are output. The first points to the previous | |
1917 | -- declaration with a general "no conformance" message. | |
1918 | -- The second is the detailed reason, supplied as Msg. The | |
1919 | -- parameter N provide information for a possible & insertion | |
1920 | -- in the message, and also provides the location for posting | |
1921 | -- the message in the absence of a specified Err_Loc location. | |
1922 | ||
1923 | ----------------------- | |
1924 | -- Conformance_Error -- | |
1925 | ----------------------- | |
1926 | ||
1927 | procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is | |
1928 | Enode : Node_Id; | |
1929 | ||
1930 | begin | |
1931 | Conforms := False; | |
1932 | ||
1933 | if Errmsg then | |
1934 | if No (Err_Loc) then | |
1935 | Enode := N; | |
1936 | else | |
1937 | Enode := Err_Loc; | |
1938 | end if; | |
1939 | ||
1940 | Error_Msg_Sloc := Sloc (Old_Id); | |
1941 | ||
1942 | case Ctype is | |
1943 | when Type_Conformant => | |
1944 | Error_Msg_N | |
1945 | ("not type conformant with declaration#!", Enode); | |
1946 | ||
1947 | when Mode_Conformant => | |
1948 | Error_Msg_N | |
1949 | ("not mode conformant with declaration#!", Enode); | |
1950 | ||
1951 | when Subtype_Conformant => | |
1952 | Error_Msg_N | |
1953 | ("not subtype conformant with declaration#!", Enode); | |
1954 | ||
1955 | when Fully_Conformant => | |
1956 | Error_Msg_N | |
1957 | ("not fully conformant with declaration#!", Enode); | |
1958 | end case; | |
1959 | ||
1960 | Error_Msg_NE (Msg, Enode, N); | |
1961 | end if; | |
1962 | end Conformance_Error; | |
1963 | ||
1964 | -- Start of processing for Check_Conformance | |
1965 | ||
1966 | begin | |
1967 | Conforms := True; | |
1968 | ||
1969 | -- We need a special case for operators, since they don't | |
1970 | -- appear explicitly. | |
1971 | ||
1972 | if Ctype = Type_Conformant then | |
1973 | if Ekind (New_Id) = E_Operator | |
1974 | and then Operator_Matches_Spec (New_Id, Old_Id) | |
1975 | then | |
1976 | return; | |
1977 | end if; | |
1978 | end if; | |
1979 | ||
1980 | -- If both are functions/operators, check return types conform | |
1981 | ||
1982 | if Old_Type /= Standard_Void_Type | |
1983 | and then New_Type /= Standard_Void_Type | |
1984 | then | |
1985 | if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then | |
1986 | Conformance_Error ("return type does not match!", New_Id); | |
1987 | return; | |
1988 | end if; | |
1989 | ||
1990 | -- If either is a function/operator and the other isn't, error | |
1991 | ||
1992 | elsif Old_Type /= Standard_Void_Type | |
1993 | or else New_Type /= Standard_Void_Type | |
1994 | then | |
1995 | Conformance_Error ("functions can only match functions!", New_Id); | |
1996 | return; | |
1997 | end if; | |
1998 | ||
1999 | -- In subtype conformant case, conventions must match (RM 6.3.1(16)) | |
2000 | -- If this is a renaming as body, refine error message to indicate that | |
2001 | -- the conflict is with the original declaration. If the entity is not | |
2002 | -- frozen, the conventions don't have to match, the one of the renamed | |
2003 | -- entity is inherited. | |
2004 | ||
2005 | if Ctype >= Subtype_Conformant then | |
996ae0b0 RK |
2006 | if Convention (Old_Id) /= Convention (New_Id) then |
2007 | ||
2008 | if not Is_Frozen (New_Id) then | |
2009 | null; | |
2010 | ||
2011 | elsif Present (Err_Loc) | |
2012 | and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration | |
2013 | and then Present (Corresponding_Spec (Err_Loc)) | |
2014 | then | |
2015 | Error_Msg_Name_1 := Chars (New_Id); | |
2016 | Error_Msg_Name_2 := | |
2017 | Name_Ada + Convention_Id'Pos (Convention (New_Id)); | |
2018 | ||
2019 | Conformance_Error ("prior declaration for% has convention %!"); | |
2020 | ||
2021 | else | |
2022 | Conformance_Error ("calling conventions do not match!"); | |
2023 | end if; | |
2024 | ||
2025 | return; | |
2026 | ||
2027 | elsif Is_Formal_Subprogram (Old_Id) | |
2028 | or else Is_Formal_Subprogram (New_Id) | |
2029 | then | |
2030 | Conformance_Error ("formal subprograms not allowed!"); | |
2031 | return; | |
2032 | end if; | |
2033 | end if; | |
2034 | ||
2035 | -- Deal with parameters | |
2036 | ||
2037 | -- Note: we use the entity information, rather than going directly | |
2038 | -- to the specification in the tree. This is not only simpler, but | |
2039 | -- absolutely necessary for some cases of conformance tests between | |
2040 | -- operators, where the declaration tree simply does not exist! | |
2041 | ||
2042 | Old_Formal := First_Formal (Old_Id); | |
2043 | New_Formal := First_Formal (New_Id); | |
2044 | ||
2045 | while Present (Old_Formal) and then Present (New_Formal) loop | |
fbf5a39b AC |
2046 | if Ctype = Fully_Conformant then |
2047 | ||
2048 | -- Names must match. Error message is more accurate if we do | |
2049 | -- this before checking that the types of the formals match. | |
2050 | ||
2051 | if Chars (Old_Formal) /= Chars (New_Formal) then | |
2052 | Conformance_Error ("name & does not match!", New_Formal); | |
2053 | ||
2054 | -- Set error posted flag on new formal as well to stop | |
2055 | -- junk cascaded messages in some cases. | |
2056 | ||
2057 | Set_Error_Posted (New_Formal); | |
2058 | return; | |
2059 | end if; | |
2060 | end if; | |
996ae0b0 RK |
2061 | |
2062 | -- Types must always match. In the visible part of an instance, | |
2063 | -- usual overloading rules for dispatching operations apply, and | |
2064 | -- we check base types (not the actual subtypes). | |
2065 | ||
2066 | if In_Instance_Visible_Part | |
2067 | and then Is_Dispatching_Operation (New_Id) | |
2068 | then | |
2069 | if not Conforming_Types | |
2070 | (Base_Type (Etype (Old_Formal)), | |
2071 | Base_Type (Etype (New_Formal)), Ctype, Get_Inst) | |
2072 | then | |
2073 | Conformance_Error ("type of & does not match!", New_Formal); | |
2074 | return; | |
2075 | end if; | |
2076 | ||
2077 | elsif not Conforming_Types | |
2078 | (Etype (Old_Formal), Etype (New_Formal), Ctype, Get_Inst) | |
2079 | then | |
2080 | Conformance_Error ("type of & does not match!", New_Formal); | |
2081 | return; | |
2082 | end if; | |
2083 | ||
2084 | -- For mode conformance, mode must match | |
2085 | ||
2086 | if Ctype >= Mode_Conformant | |
2087 | and then Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) | |
2088 | then | |
2089 | Conformance_Error ("mode of & does not match!", New_Formal); | |
2090 | return; | |
2091 | end if; | |
2092 | ||
2093 | -- Full conformance checks | |
2094 | ||
2095 | if Ctype = Fully_Conformant then | |
2096 | ||
fbf5a39b AC |
2097 | -- We have checked already that names match. |
2098 | -- Check default expressions for in parameters | |
996ae0b0 | 2099 | |
fbf5a39b | 2100 | if Parameter_Mode (Old_Formal) = E_In_Parameter then |
996ae0b0 RK |
2101 | declare |
2102 | NewD : constant Boolean := | |
2103 | Present (Default_Value (New_Formal)); | |
2104 | OldD : constant Boolean := | |
2105 | Present (Default_Value (Old_Formal)); | |
2106 | begin | |
2107 | if NewD or OldD then | |
2108 | ||
fbf5a39b AC |
2109 | -- The old default value has been analyzed because |
2110 | -- the current full declaration will have frozen | |
996ae0b0 | 2111 | -- everything before. The new default values have not |
fbf5a39b AC |
2112 | -- been analyzed, so analyze them now before we check |
2113 | -- for conformance. | |
996ae0b0 RK |
2114 | |
2115 | if NewD then | |
2116 | New_Scope (New_Id); | |
fbf5a39b AC |
2117 | Analyze_Per_Use_Expression |
2118 | (Default_Value (New_Formal), Etype (New_Formal)); | |
996ae0b0 RK |
2119 | End_Scope; |
2120 | end if; | |
2121 | ||
2122 | if not (NewD and OldD) | |
2123 | or else not Fully_Conformant_Expressions | |
2124 | (Default_Value (Old_Formal), | |
2125 | Default_Value (New_Formal)) | |
2126 | then | |
2127 | Conformance_Error | |
2128 | ("default expression for & does not match!", | |
2129 | New_Formal); | |
2130 | return; | |
2131 | end if; | |
2132 | end if; | |
2133 | end; | |
2134 | end if; | |
2135 | end if; | |
2136 | ||
2137 | -- A couple of special checks for Ada 83 mode. These checks are | |
2138 | -- skipped if either entity is an operator in package Standard. | |
2139 | -- or if either old or new instance is not from the source program. | |
2140 | ||
2141 | if Ada_83 | |
2142 | and then Sloc (Old_Id) > Standard_Location | |
2143 | and then Sloc (New_Id) > Standard_Location | |
2144 | and then Comes_From_Source (Old_Id) | |
2145 | and then Comes_From_Source (New_Id) | |
2146 | then | |
2147 | declare | |
2148 | Old_Param : constant Node_Id := Declaration_Node (Old_Formal); | |
2149 | New_Param : constant Node_Id := Declaration_Node (New_Formal); | |
2150 | ||
2151 | begin | |
2152 | -- Explicit IN must be present or absent in both cases. This | |
2153 | -- test is required only in the full conformance case. | |
2154 | ||
2155 | if In_Present (Old_Param) /= In_Present (New_Param) | |
2156 | and then Ctype = Fully_Conformant | |
2157 | then | |
2158 | Conformance_Error | |
2159 | ("(Ada 83) IN must appear in both declarations", | |
2160 | New_Formal); | |
2161 | return; | |
2162 | end if; | |
2163 | ||
2164 | -- Grouping (use of comma in param lists) must be the same | |
2165 | -- This is where we catch a misconformance like: | |
2166 | ||
2167 | -- A,B : Integer | |
2168 | -- A : Integer; B : Integer | |
2169 | ||
2170 | -- which are represented identically in the tree except | |
2171 | -- for the setting of the flags More_Ids and Prev_Ids. | |
2172 | ||
2173 | if More_Ids (Old_Param) /= More_Ids (New_Param) | |
2174 | or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param) | |
2175 | then | |
2176 | Conformance_Error | |
2177 | ("grouping of & does not match!", New_Formal); | |
2178 | return; | |
2179 | end if; | |
2180 | end; | |
2181 | end if; | |
2182 | ||
2183 | Next_Formal (Old_Formal); | |
2184 | Next_Formal (New_Formal); | |
2185 | end loop; | |
2186 | ||
2187 | if Present (Old_Formal) then | |
2188 | Conformance_Error ("too few parameters!"); | |
2189 | return; | |
2190 | ||
2191 | elsif Present (New_Formal) then | |
2192 | Conformance_Error ("too many parameters!", New_Formal); | |
2193 | return; | |
2194 | end if; | |
2195 | ||
2196 | end Check_Conformance; | |
2197 | ||
2198 | ------------------------------ | |
2199 | -- Check_Delayed_Subprogram -- | |
2200 | ------------------------------ | |
2201 | ||
2202 | procedure Check_Delayed_Subprogram (Designator : Entity_Id) is | |
2203 | F : Entity_Id; | |
2204 | ||
2205 | procedure Possible_Freeze (T : Entity_Id); | |
2206 | -- T is the type of either a formal parameter or of the return type. | |
2207 | -- If T is not yet frozen and needs a delayed freeze, then the | |
2208 | -- subprogram itself must be delayed. | |
2209 | ||
2210 | procedure Possible_Freeze (T : Entity_Id) is | |
2211 | begin | |
2212 | if Has_Delayed_Freeze (T) | |
2213 | and then not Is_Frozen (T) | |
2214 | then | |
2215 | Set_Has_Delayed_Freeze (Designator); | |
2216 | ||
2217 | elsif Is_Access_Type (T) | |
2218 | and then Has_Delayed_Freeze (Designated_Type (T)) | |
2219 | and then not Is_Frozen (Designated_Type (T)) | |
2220 | then | |
2221 | Set_Has_Delayed_Freeze (Designator); | |
2222 | end if; | |
2223 | end Possible_Freeze; | |
2224 | ||
2225 | -- Start of processing for Check_Delayed_Subprogram | |
2226 | ||
2227 | begin | |
2228 | -- Never need to freeze abstract subprogram | |
2229 | ||
2230 | if Is_Abstract (Designator) then | |
2231 | null; | |
2232 | else | |
2233 | -- Need delayed freeze if return type itself needs a delayed | |
2234 | -- freeze and is not yet frozen. | |
2235 | ||
2236 | Possible_Freeze (Etype (Designator)); | |
2237 | Possible_Freeze (Base_Type (Etype (Designator))); -- needed ??? | |
2238 | ||
2239 | -- Need delayed freeze if any of the formal types themselves need | |
2240 | -- a delayed freeze and are not yet frozen. | |
2241 | ||
2242 | F := First_Formal (Designator); | |
2243 | while Present (F) loop | |
2244 | Possible_Freeze (Etype (F)); | |
2245 | Possible_Freeze (Base_Type (Etype (F))); -- needed ??? | |
2246 | Next_Formal (F); | |
2247 | end loop; | |
2248 | end if; | |
2249 | ||
2250 | -- Mark functions that return by reference. Note that it cannot be | |
2251 | -- done for delayed_freeze subprograms because the underlying | |
2252 | -- returned type may not be known yet (for private types) | |
2253 | ||
2254 | if not Has_Delayed_Freeze (Designator) | |
2255 | and then Expander_Active | |
2256 | then | |
2257 | declare | |
2258 | Typ : constant Entity_Id := Etype (Designator); | |
2259 | Utyp : constant Entity_Id := Underlying_Type (Typ); | |
2260 | ||
2261 | begin | |
2262 | if Is_Return_By_Reference_Type (Typ) then | |
2263 | Set_Returns_By_Ref (Designator); | |
2264 | ||
2265 | elsif Present (Utyp) and then Controlled_Type (Utyp) then | |
2266 | Set_Returns_By_Ref (Designator); | |
2267 | end if; | |
2268 | end; | |
2269 | end if; | |
2270 | end Check_Delayed_Subprogram; | |
2271 | ||
2272 | ------------------------------------ | |
2273 | -- Check_Discriminant_Conformance -- | |
2274 | ------------------------------------ | |
2275 | ||
2276 | procedure Check_Discriminant_Conformance | |
2277 | (N : Node_Id; | |
2278 | Prev : Entity_Id; | |
2279 | Prev_Loc : Node_Id) | |
2280 | is | |
2281 | Old_Discr : Entity_Id := First_Discriminant (Prev); | |
2282 | New_Discr : Node_Id := First (Discriminant_Specifications (N)); | |
2283 | New_Discr_Id : Entity_Id; | |
2284 | New_Discr_Type : Entity_Id; | |
2285 | ||
2286 | procedure Conformance_Error (Msg : String; N : Node_Id); | |
2287 | -- Post error message for conformance error on given node. | |
2288 | -- Two messages are output. The first points to the previous | |
2289 | -- declaration with a general "no conformance" message. | |
2290 | -- The second is the detailed reason, supplied as Msg. The | |
2291 | -- parameter N provide information for a possible & insertion | |
2292 | -- in the message. | |
2293 | ||
2294 | ----------------------- | |
2295 | -- Conformance_Error -- | |
2296 | ----------------------- | |
2297 | ||
2298 | procedure Conformance_Error (Msg : String; N : Node_Id) is | |
2299 | begin | |
2300 | Error_Msg_Sloc := Sloc (Prev_Loc); | |
2301 | Error_Msg_N ("not fully conformant with declaration#!", N); | |
2302 | Error_Msg_NE (Msg, N, N); | |
2303 | end Conformance_Error; | |
2304 | ||
2305 | -- Start of processing for Check_Discriminant_Conformance | |
2306 | ||
2307 | begin | |
2308 | while Present (Old_Discr) and then Present (New_Discr) loop | |
2309 | ||
2310 | New_Discr_Id := Defining_Identifier (New_Discr); | |
2311 | ||
2312 | -- The subtype mark of the discriminant on the full type | |
2313 | -- has not been analyzed so we do it here. For an access | |
2314 | -- discriminant a new type is created. | |
2315 | ||
2316 | if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then | |
2317 | New_Discr_Type := | |
2318 | Access_Definition (N, Discriminant_Type (New_Discr)); | |
2319 | ||
2320 | else | |
2321 | Analyze (Discriminant_Type (New_Discr)); | |
2322 | New_Discr_Type := Etype (Discriminant_Type (New_Discr)); | |
2323 | end if; | |
2324 | ||
2325 | if not Conforming_Types | |
2326 | (Etype (Old_Discr), New_Discr_Type, Fully_Conformant) | |
2327 | then | |
2328 | Conformance_Error ("type of & does not match!", New_Discr_Id); | |
2329 | return; | |
fbf5a39b AC |
2330 | else |
2331 | -- Treat the new discriminant as an occurrence of the old | |
2332 | -- one, for navigation purposes, and fill in some semantic | |
2333 | -- information, for completeness. | |
2334 | ||
2335 | Generate_Reference (Old_Discr, New_Discr_Id, 'r'); | |
2336 | Set_Etype (New_Discr_Id, Etype (Old_Discr)); | |
2337 | Set_Scope (New_Discr_Id, Scope (Old_Discr)); | |
996ae0b0 RK |
2338 | end if; |
2339 | ||
2340 | -- Names must match | |
2341 | ||
2342 | if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then | |
2343 | Conformance_Error ("name & does not match!", New_Discr_Id); | |
2344 | return; | |
2345 | end if; | |
2346 | ||
2347 | -- Default expressions must match | |
2348 | ||
2349 | declare | |
2350 | NewD : constant Boolean := | |
2351 | Present (Expression (New_Discr)); | |
2352 | OldD : constant Boolean := | |
2353 | Present (Expression (Parent (Old_Discr))); | |
2354 | ||
2355 | begin | |
2356 | if NewD or OldD then | |
2357 | ||
2358 | -- The old default value has been analyzed and expanded, | |
2359 | -- because the current full declaration will have frozen | |
2360 | -- everything before. The new default values have not | |
2361 | -- been expanded, so expand now to check conformance. | |
2362 | ||
2363 | if NewD then | |
fbf5a39b | 2364 | Analyze_Per_Use_Expression |
996ae0b0 RK |
2365 | (Expression (New_Discr), New_Discr_Type); |
2366 | end if; | |
2367 | ||
2368 | if not (NewD and OldD) | |
2369 | or else not Fully_Conformant_Expressions | |
2370 | (Expression (Parent (Old_Discr)), | |
2371 | Expression (New_Discr)) | |
2372 | ||
2373 | then | |
2374 | Conformance_Error | |
2375 | ("default expression for & does not match!", | |
2376 | New_Discr_Id); | |
2377 | return; | |
2378 | end if; | |
2379 | end if; | |
2380 | end; | |
2381 | ||
2382 | -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X) | |
2383 | ||
2384 | if Ada_83 then | |
2385 | declare | |
2386 | Old_Disc : constant Node_Id := Declaration_Node (Old_Discr); | |
2387 | ||
2388 | begin | |
2389 | -- Grouping (use of comma in param lists) must be the same | |
2390 | -- This is where we catch a misconformance like: | |
2391 | ||
2392 | -- A,B : Integer | |
2393 | -- A : Integer; B : Integer | |
2394 | ||
2395 | -- which are represented identically in the tree except | |
2396 | -- for the setting of the flags More_Ids and Prev_Ids. | |
2397 | ||
2398 | if More_Ids (Old_Disc) /= More_Ids (New_Discr) | |
2399 | or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr) | |
2400 | then | |
2401 | Conformance_Error | |
2402 | ("grouping of & does not match!", New_Discr_Id); | |
2403 | return; | |
2404 | end if; | |
2405 | end; | |
2406 | end if; | |
2407 | ||
2408 | Next_Discriminant (Old_Discr); | |
2409 | Next (New_Discr); | |
2410 | end loop; | |
2411 | ||
2412 | if Present (Old_Discr) then | |
2413 | Conformance_Error ("too few discriminants!", Defining_Identifier (N)); | |
2414 | return; | |
2415 | ||
2416 | elsif Present (New_Discr) then | |
2417 | Conformance_Error | |
2418 | ("too many discriminants!", Defining_Identifier (New_Discr)); | |
2419 | return; | |
2420 | end if; | |
2421 | end Check_Discriminant_Conformance; | |
2422 | ||
2423 | ---------------------------- | |
2424 | -- Check_Fully_Conformant -- | |
2425 | ---------------------------- | |
2426 | ||
2427 | procedure Check_Fully_Conformant | |
2428 | (New_Id : Entity_Id; | |
2429 | Old_Id : Entity_Id; | |
2430 | Err_Loc : Node_Id := Empty) | |
2431 | is | |
2432 | Result : Boolean; | |
2433 | ||
2434 | begin | |
2435 | Check_Conformance | |
2436 | (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc); | |
2437 | end Check_Fully_Conformant; | |
2438 | ||
2439 | --------------------------- | |
2440 | -- Check_Mode_Conformant -- | |
2441 | --------------------------- | |
2442 | ||
2443 | procedure Check_Mode_Conformant | |
2444 | (New_Id : Entity_Id; | |
2445 | Old_Id : Entity_Id; | |
2446 | Err_Loc : Node_Id := Empty; | |
2447 | Get_Inst : Boolean := False) | |
2448 | is | |
2449 | Result : Boolean; | |
2450 | ||
2451 | begin | |
2452 | Check_Conformance | |
2453 | (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst); | |
2454 | end Check_Mode_Conformant; | |
2455 | ||
fbf5a39b AC |
2456 | -------------------------------- |
2457 | -- Check_Overriding_Operation -- | |
2458 | -------------------------------- | |
2459 | ||
2460 | procedure Check_Overriding_Operation | |
2461 | (N : Node_Id; | |
2462 | Subp : Entity_Id) | |
2463 | is | |
2464 | Arg1 : Node_Id; | |
2465 | Decl : Node_Id; | |
2466 | Has_Pragma : Boolean := False; | |
2467 | ||
2468 | begin | |
2469 | -- See whether there is an overriding pragma immediately following | |
2470 | -- the declaration. Intervening pragmas, such as Inline, are allowed. | |
2471 | ||
2472 | Decl := Next (N); | |
2473 | while Present (Decl) | |
2474 | and then Nkind (Decl) = N_Pragma | |
2475 | loop | |
2476 | if Chars (Decl) = Name_Overriding | |
2477 | or else Chars (Decl) = Name_Optional_Overriding | |
2478 | then | |
2479 | -- For now disable the use of these pragmas, until the ARG | |
2480 | -- finalizes the design of this feature. | |
2481 | ||
2482 | Error_Msg_N ("?unrecognized pragma", Decl); | |
2483 | ||
2484 | if not Is_Overriding_Operation (Subp) then | |
2485 | ||
2486 | -- Before emitting an error message, check whether this | |
2487 | -- may override an operation that is not yet visible, as | |
2488 | -- in the case of a derivation of a private operation in | |
2489 | -- a child unit. Such an operation is introduced with a | |
2490 | -- different name, but its alias is the parent operation. | |
2491 | ||
2492 | declare | |
2493 | E : Entity_Id; | |
2494 | ||
2495 | begin | |
2496 | E := First_Entity (Current_Scope); | |
2497 | ||
2498 | while Present (E) loop | |
2499 | if Ekind (E) = Ekind (Subp) | |
2500 | and then not Comes_From_Source (E) | |
2501 | and then Present (Alias (E)) | |
2502 | and then Chars (Alias (E)) = Chars (Subp) | |
2503 | and then In_Open_Scopes (Scope (Alias (E))) | |
2504 | then | |
2505 | exit; | |
2506 | else | |
2507 | Next_Entity (E); | |
2508 | end if; | |
2509 | end loop; | |
2510 | ||
2511 | if No (E) then | |
2512 | Error_Msg_NE | |
2513 | ("& must override an inherited operation", | |
2514 | Decl, Subp); | |
2515 | end if; | |
2516 | end; | |
2517 | end if; | |
2518 | ||
2519 | -- Verify syntax of pragma | |
2520 | ||
2521 | Arg1 := First (Pragma_Argument_Associations (Decl)); | |
2522 | ||
2523 | if Present (Arg1) then | |
2524 | if not Is_Entity_Name (Expression (Arg1)) then | |
2525 | Error_Msg_N ("pragma applies to local subprogram", Decl); | |
2526 | ||
2527 | elsif Chars (Expression (Arg1)) /= Chars (Subp) then | |
2528 | Error_Msg_N | |
2529 | ("pragma must apply to preceding subprogram", Decl); | |
2530 | ||
2531 | elsif Present (Next (Arg1)) then | |
2532 | Error_Msg_N ("illegal pragma format", Decl); | |
2533 | end if; | |
2534 | end if; | |
2535 | ||
2536 | Set_Analyzed (Decl); | |
2537 | Has_Pragma := True; | |
2538 | exit; | |
2539 | end if; | |
2540 | ||
2541 | Next (Decl); | |
2542 | end loop; | |
2543 | ||
2544 | if not Has_Pragma | |
2545 | and then Explicit_Overriding | |
2546 | and then Is_Overriding_Operation (Subp) | |
2547 | then | |
2548 | Error_Msg_NE ("Missing overriding pragma for&", Subp, Subp); | |
2549 | end if; | |
2550 | end Check_Overriding_Operation; | |
2551 | ||
996ae0b0 RK |
2552 | ------------------- |
2553 | -- Check_Returns -- | |
2554 | ------------------- | |
2555 | ||
2556 | procedure Check_Returns | |
2557 | (HSS : Node_Id; | |
2558 | Mode : Character; | |
2559 | Err : out Boolean) | |
2560 | is | |
2561 | Handler : Node_Id; | |
2562 | ||
2563 | procedure Check_Statement_Sequence (L : List_Id); | |
2564 | -- Internal recursive procedure to check a list of statements for proper | |
2565 | -- termination by a return statement (or a transfer of control or a | |
2566 | -- compound statement that is itself internally properly terminated). | |
2567 | ||
2568 | ------------------------------ | |
2569 | -- Check_Statement_Sequence -- | |
2570 | ------------------------------ | |
2571 | ||
2572 | procedure Check_Statement_Sequence (L : List_Id) is | |
2573 | Last_Stm : Node_Id; | |
2574 | Kind : Node_Kind; | |
2575 | ||
2576 | Raise_Exception_Call : Boolean; | |
2577 | -- Set True if statement sequence terminated by Raise_Exception call | |
2578 | -- or a Reraise_Occurrence call. | |
2579 | ||
2580 | begin | |
2581 | Raise_Exception_Call := False; | |
2582 | ||
2583 | -- Get last real statement | |
2584 | ||
2585 | Last_Stm := Last (L); | |
2586 | ||
2587 | -- Don't count pragmas | |
2588 | ||
2589 | while Nkind (Last_Stm) = N_Pragma | |
2590 | ||
2591 | -- Don't count call to SS_Release (can happen after Raise_Exception) | |
2592 | ||
2593 | or else | |
2594 | (Nkind (Last_Stm) = N_Procedure_Call_Statement | |
2595 | and then | |
2596 | Nkind (Name (Last_Stm)) = N_Identifier | |
2597 | and then | |
2598 | Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release)) | |
2599 | ||
2600 | -- Don't count exception junk | |
2601 | ||
2602 | or else | |
2603 | ((Nkind (Last_Stm) = N_Goto_Statement | |
2604 | or else Nkind (Last_Stm) = N_Label | |
2605 | or else Nkind (Last_Stm) = N_Object_Declaration) | |
2606 | and then Exception_Junk (Last_Stm)) | |
2607 | loop | |
2608 | Prev (Last_Stm); | |
2609 | end loop; | |
2610 | ||
2611 | -- Here we have the "real" last statement | |
2612 | ||
2613 | Kind := Nkind (Last_Stm); | |
2614 | ||
2615 | -- Transfer of control, OK. Note that in the No_Return procedure | |
2616 | -- case, we already diagnosed any explicit return statements, so | |
2617 | -- we can treat them as OK in this context. | |
2618 | ||
2619 | if Is_Transfer (Last_Stm) then | |
2620 | return; | |
2621 | ||
2622 | -- Check cases of explicit non-indirect procedure calls | |
2623 | ||
2624 | elsif Kind = N_Procedure_Call_Statement | |
2625 | and then Is_Entity_Name (Name (Last_Stm)) | |
2626 | then | |
2627 | -- Check call to Raise_Exception procedure which is treated | |
2628 | -- specially, as is a call to Reraise_Occurrence. | |
2629 | ||
2630 | -- We suppress the warning in these cases since it is likely that | |
2631 | -- the programmer really does not expect to deal with the case | |
2632 | -- of Null_Occurrence, and thus would find a warning about a | |
2633 | -- missing return curious, and raising Program_Error does not | |
2634 | -- seem such a bad behavior if this does occur. | |
2635 | ||
2636 | if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception) | |
2637 | or else | |
2638 | Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence) | |
2639 | then | |
2640 | Raise_Exception_Call := True; | |
2641 | ||
2642 | -- For Raise_Exception call, test first argument, if it is | |
2643 | -- an attribute reference for a 'Identity call, then we know | |
2644 | -- that the call cannot possibly return. | |
2645 | ||
2646 | declare | |
2647 | Arg : constant Node_Id := | |
2648 | Original_Node (First_Actual (Last_Stm)); | |
2649 | ||
2650 | begin | |
2651 | if Nkind (Arg) = N_Attribute_Reference | |
2652 | and then Attribute_Name (Arg) = Name_Identity | |
2653 | then | |
2654 | return; | |
2655 | end if; | |
2656 | end; | |
2657 | end if; | |
2658 | ||
2659 | -- If statement, need to look inside if there is an else and check | |
2660 | -- each constituent statement sequence for proper termination. | |
2661 | ||
2662 | elsif Kind = N_If_Statement | |
2663 | and then Present (Else_Statements (Last_Stm)) | |
2664 | then | |
2665 | Check_Statement_Sequence (Then_Statements (Last_Stm)); | |
2666 | Check_Statement_Sequence (Else_Statements (Last_Stm)); | |
2667 | ||
2668 | if Present (Elsif_Parts (Last_Stm)) then | |
2669 | declare | |
2670 | Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm)); | |
2671 | ||
2672 | begin | |
2673 | while Present (Elsif_Part) loop | |
2674 | Check_Statement_Sequence (Then_Statements (Elsif_Part)); | |
2675 | Next (Elsif_Part); | |
2676 | end loop; | |
2677 | end; | |
2678 | end if; | |
2679 | ||
2680 | return; | |
2681 | ||
2682 | -- Case statement, check each case for proper termination | |
2683 | ||
2684 | elsif Kind = N_Case_Statement then | |
2685 | declare | |
2686 | Case_Alt : Node_Id; | |
2687 | ||
2688 | begin | |
2689 | Case_Alt := First_Non_Pragma (Alternatives (Last_Stm)); | |
2690 | while Present (Case_Alt) loop | |
2691 | Check_Statement_Sequence (Statements (Case_Alt)); | |
2692 | Next_Non_Pragma (Case_Alt); | |
2693 | end loop; | |
2694 | end; | |
2695 | ||
2696 | return; | |
2697 | ||
2698 | -- Block statement, check its handled sequence of statements | |
2699 | ||
2700 | elsif Kind = N_Block_Statement then | |
2701 | declare | |
2702 | Err1 : Boolean; | |
2703 | ||
2704 | begin | |
2705 | Check_Returns | |
2706 | (Handled_Statement_Sequence (Last_Stm), Mode, Err1); | |
2707 | ||
2708 | if Err1 then | |
2709 | Err := True; | |
2710 | end if; | |
2711 | ||
2712 | return; | |
2713 | end; | |
2714 | ||
2715 | -- Loop statement. If there is an iteration scheme, we can definitely | |
2716 | -- fall out of the loop. Similarly if there is an exit statement, we | |
2717 | -- can fall out. In either case we need a following return. | |
2718 | ||
2719 | elsif Kind = N_Loop_Statement then | |
2720 | if Present (Iteration_Scheme (Last_Stm)) | |
2721 | or else Has_Exit (Entity (Identifier (Last_Stm))) | |
2722 | then | |
2723 | null; | |
2724 | ||
2725 | -- A loop with no exit statement or iteration scheme if either | |
2726 | -- an inifite loop, or it has some other exit (raise/return). | |
2727 | -- In either case, no warning is required. | |
2728 | ||
2729 | else | |
2730 | return; | |
2731 | end if; | |
2732 | ||
2733 | -- Timed entry call, check entry call and delay alternatives | |
2734 | ||
2735 | -- Note: in expanded code, the timed entry call has been converted | |
2736 | -- to a set of expanded statements on which the check will work | |
2737 | -- correctly in any case. | |
2738 | ||
2739 | elsif Kind = N_Timed_Entry_Call then | |
2740 | declare | |
2741 | ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm); | |
2742 | DCA : constant Node_Id := Delay_Alternative (Last_Stm); | |
2743 | ||
2744 | begin | |
2745 | -- If statement sequence of entry call alternative is missing, | |
2746 | -- then we can definitely fall through, and we post the error | |
2747 | -- message on the entry call alternative itself. | |
2748 | ||
2749 | if No (Statements (ECA)) then | |
2750 | Last_Stm := ECA; | |
2751 | ||
2752 | -- If statement sequence of delay alternative is missing, then | |
2753 | -- we can definitely fall through, and we post the error | |
2754 | -- message on the delay alternative itself. | |
2755 | ||
2756 | -- Note: if both ECA and DCA are missing the return, then we | |
2757 | -- post only one message, should be enough to fix the bugs. | |
2758 | -- If not we will get a message next time on the DCA when the | |
2759 | -- ECA is fixed! | |
2760 | ||
2761 | elsif No (Statements (DCA)) then | |
2762 | Last_Stm := DCA; | |
2763 | ||
2764 | -- Else check both statement sequences | |
2765 | ||
2766 | else | |
2767 | Check_Statement_Sequence (Statements (ECA)); | |
2768 | Check_Statement_Sequence (Statements (DCA)); | |
2769 | return; | |
2770 | end if; | |
2771 | end; | |
2772 | ||
2773 | -- Conditional entry call, check entry call and else part | |
2774 | ||
2775 | -- Note: in expanded code, the conditional entry call has been | |
2776 | -- converted to a set of expanded statements on which the check | |
2777 | -- will work correctly in any case. | |
2778 | ||
2779 | elsif Kind = N_Conditional_Entry_Call then | |
2780 | declare | |
2781 | ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm); | |
2782 | ||
2783 | begin | |
2784 | -- If statement sequence of entry call alternative is missing, | |
2785 | -- then we can definitely fall through, and we post the error | |
2786 | -- message on the entry call alternative itself. | |
2787 | ||
2788 | if No (Statements (ECA)) then | |
2789 | Last_Stm := ECA; | |
2790 | ||
2791 | -- Else check statement sequence and else part | |
2792 | ||
2793 | else | |
2794 | Check_Statement_Sequence (Statements (ECA)); | |
2795 | Check_Statement_Sequence (Else_Statements (Last_Stm)); | |
2796 | return; | |
2797 | end if; | |
2798 | end; | |
2799 | end if; | |
2800 | ||
2801 | -- If we fall through, issue appropriate message | |
2802 | ||
2803 | if Mode = 'F' then | |
2804 | ||
2805 | if not Raise_Exception_Call then | |
2806 | Error_Msg_N | |
2807 | ("?RETURN statement missing following this statement!", | |
2808 | Last_Stm); | |
2809 | Error_Msg_N | |
2810 | ("\?Program_Error may be raised at run time", | |
2811 | Last_Stm); | |
2812 | end if; | |
2813 | ||
2814 | -- Note: we set Err even though we have not issued a warning | |
2815 | -- because we still have a case of a missing return. This is | |
2816 | -- an extremely marginal case, probably will never be noticed | |
2817 | -- but we might as well get it right. | |
2818 | ||
2819 | Err := True; | |
2820 | ||
2821 | else | |
2822 | Error_Msg_N | |
2823 | ("implied return after this statement not allowed (No_Return)", | |
2824 | Last_Stm); | |
2825 | end if; | |
2826 | end Check_Statement_Sequence; | |
2827 | ||
2828 | -- Start of processing for Check_Returns | |
2829 | ||
2830 | begin | |
2831 | Err := False; | |
2832 | Check_Statement_Sequence (Statements (HSS)); | |
2833 | ||
2834 | if Present (Exception_Handlers (HSS)) then | |
2835 | Handler := First_Non_Pragma (Exception_Handlers (HSS)); | |
2836 | while Present (Handler) loop | |
2837 | Check_Statement_Sequence (Statements (Handler)); | |
2838 | Next_Non_Pragma (Handler); | |
2839 | end loop; | |
2840 | end if; | |
2841 | end Check_Returns; | |
2842 | ||
2843 | ---------------------------- | |
2844 | -- Check_Subprogram_Order -- | |
2845 | ---------------------------- | |
2846 | ||
2847 | procedure Check_Subprogram_Order (N : Node_Id) is | |
2848 | ||
2849 | function Subprogram_Name_Greater (S1, S2 : String) return Boolean; | |
2850 | -- This is used to check if S1 > S2 in the sense required by this | |
2851 | -- test, for example nameab < namec, but name2 < name10. | |
2852 | ||
2853 | function Subprogram_Name_Greater (S1, S2 : String) return Boolean is | |
2854 | L1, L2 : Positive; | |
2855 | N1, N2 : Natural; | |
2856 | ||
2857 | begin | |
2858 | -- Remove trailing numeric parts | |
2859 | ||
2860 | L1 := S1'Last; | |
2861 | while S1 (L1) in '0' .. '9' loop | |
2862 | L1 := L1 - 1; | |
2863 | end loop; | |
2864 | ||
2865 | L2 := S2'Last; | |
2866 | while S2 (L2) in '0' .. '9' loop | |
2867 | L2 := L2 - 1; | |
2868 | end loop; | |
2869 | ||
2870 | -- If non-numeric parts non-equal, that's decisive | |
2871 | ||
2872 | if S1 (S1'First .. L1) < S2 (S2'First .. L2) then | |
2873 | return False; | |
2874 | ||
2875 | elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then | |
2876 | return True; | |
2877 | ||
2878 | -- If non-numeric parts equal, compare suffixed numeric parts. Note | |
2879 | -- that a missing suffix is treated as numeric zero in this test. | |
2880 | ||
2881 | else | |
2882 | N1 := 0; | |
2883 | while L1 < S1'Last loop | |
2884 | L1 := L1 + 1; | |
2885 | N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0'); | |
2886 | end loop; | |
2887 | ||
2888 | N2 := 0; | |
2889 | while L2 < S2'Last loop | |
2890 | L2 := L2 + 1; | |
2891 | N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0'); | |
2892 | end loop; | |
2893 | ||
2894 | return N1 > N2; | |
2895 | end if; | |
2896 | end Subprogram_Name_Greater; | |
2897 | ||
2898 | -- Start of processing for Check_Subprogram_Order | |
2899 | ||
2900 | begin | |
2901 | -- Check body in alpha order if this is option | |
2902 | ||
fbf5a39b AC |
2903 | if Style_Check |
2904 | and then Style_Check_Subprogram_Order | |
996ae0b0 RK |
2905 | and then Nkind (N) = N_Subprogram_Body |
2906 | and then Comes_From_Source (N) | |
2907 | and then In_Extended_Main_Source_Unit (N) | |
2908 | then | |
2909 | declare | |
2910 | LSN : String_Ptr | |
2911 | renames Scope_Stack.Table | |
2912 | (Scope_Stack.Last).Last_Subprogram_Name; | |
2913 | ||
2914 | Body_Id : constant Entity_Id := | |
2915 | Defining_Entity (Specification (N)); | |
2916 | ||
2917 | begin | |
2918 | Get_Decoded_Name_String (Chars (Body_Id)); | |
2919 | ||
2920 | if LSN /= null then | |
2921 | if Subprogram_Name_Greater | |
2922 | (LSN.all, Name_Buffer (1 .. Name_Len)) | |
2923 | then | |
2924 | Style.Subprogram_Not_In_Alpha_Order (Body_Id); | |
2925 | end if; | |
2926 | ||
2927 | Free (LSN); | |
2928 | end if; | |
2929 | ||
2930 | LSN := new String'(Name_Buffer (1 .. Name_Len)); | |
2931 | end; | |
2932 | end if; | |
2933 | end Check_Subprogram_Order; | |
2934 | ||
2935 | ------------------------------ | |
2936 | -- Check_Subtype_Conformant -- | |
2937 | ------------------------------ | |
2938 | ||
2939 | procedure Check_Subtype_Conformant | |
2940 | (New_Id : Entity_Id; | |
2941 | Old_Id : Entity_Id; | |
2942 | Err_Loc : Node_Id := Empty) | |
2943 | is | |
2944 | Result : Boolean; | |
2945 | ||
2946 | begin | |
2947 | Check_Conformance | |
2948 | (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc); | |
2949 | end Check_Subtype_Conformant; | |
2950 | ||
2951 | --------------------------- | |
2952 | -- Check_Type_Conformant -- | |
2953 | --------------------------- | |
2954 | ||
2955 | procedure Check_Type_Conformant | |
2956 | (New_Id : Entity_Id; | |
2957 | Old_Id : Entity_Id; | |
2958 | Err_Loc : Node_Id := Empty) | |
2959 | is | |
2960 | Result : Boolean; | |
2961 | ||
2962 | begin | |
2963 | Check_Conformance | |
2964 | (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc); | |
2965 | end Check_Type_Conformant; | |
2966 | ||
2967 | ---------------------- | |
2968 | -- Conforming_Types -- | |
2969 | ---------------------- | |
2970 | ||
2971 | function Conforming_Types | |
2972 | (T1 : Entity_Id; | |
2973 | T2 : Entity_Id; | |
2974 | Ctype : Conformance_Type; | |
2975 | Get_Inst : Boolean := False) | |
2976 | return Boolean | |
2977 | is | |
2978 | Type_1 : Entity_Id := T1; | |
2979 | Type_2 : Entity_Id := T2; | |
2980 | ||
2981 | function Base_Types_Match (T1, T2 : Entity_Id) return Boolean; | |
07fc65c4 GB |
2982 | -- If neither T1 nor T2 are generic actual types, or if they are |
2983 | -- in different scopes (e.g. parent and child instances), then verify | |
996ae0b0 RK |
2984 | -- that the base types are equal. Otherwise T1 and T2 must be |
2985 | -- on the same subtype chain. The whole purpose of this procedure | |
2986 | -- is to prevent spurious ambiguities in an instantiation that may | |
2987 | -- arise if two distinct generic types are instantiated with the | |
2988 | -- same actual. | |
2989 | ||
2990 | ---------------------- | |
2991 | -- Base_Types_Match -- | |
2992 | ---------------------- | |
2993 | ||
2994 | function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is | |
2995 | begin | |
2996 | if T1 = T2 then | |
2997 | return True; | |
2998 | ||
2999 | elsif Base_Type (T1) = Base_Type (T2) then | |
3000 | ||
3001 | -- The following is too permissive. A more precise test must | |
3002 | -- check that the generic actual is an ancestor subtype of the | |
3003 | -- other ???. | |
3004 | ||
3005 | return not Is_Generic_Actual_Type (T1) | |
07fc65c4 GB |
3006 | or else not Is_Generic_Actual_Type (T2) |
3007 | or else Scope (T1) /= Scope (T2); | |
996ae0b0 RK |
3008 | |
3009 | else | |
3010 | return False; | |
3011 | end if; | |
3012 | end Base_Types_Match; | |
3013 | ||
3014 | begin | |
3015 | -- The context is an instance association for a formal | |
3016 | -- access-to-subprogram type; the formal parameter types | |
3017 | -- require mapping because they may denote other formal | |
3018 | -- parameters of the generic unit. | |
3019 | ||
3020 | if Get_Inst then | |
3021 | Type_1 := Get_Instance_Of (T1); | |
3022 | Type_2 := Get_Instance_Of (T2); | |
3023 | end if; | |
3024 | ||
3025 | -- First see if base types match | |
3026 | ||
3027 | if Base_Types_Match (Type_1, Type_2) then | |
3028 | return Ctype <= Mode_Conformant | |
3029 | or else Subtypes_Statically_Match (Type_1, Type_2); | |
3030 | ||
3031 | elsif Is_Incomplete_Or_Private_Type (Type_1) | |
3032 | and then Present (Full_View (Type_1)) | |
3033 | and then Base_Types_Match (Full_View (Type_1), Type_2) | |
3034 | then | |
3035 | return Ctype <= Mode_Conformant | |
3036 | or else Subtypes_Statically_Match (Full_View (Type_1), Type_2); | |
3037 | ||
3038 | elsif Ekind (Type_2) = E_Incomplete_Type | |
3039 | and then Present (Full_View (Type_2)) | |
3040 | and then Base_Types_Match (Type_1, Full_View (Type_2)) | |
3041 | then | |
3042 | return Ctype <= Mode_Conformant | |
3043 | or else Subtypes_Statically_Match (Type_1, Full_View (Type_2)); | |
fbf5a39b AC |
3044 | |
3045 | elsif Is_Private_Type (Type_2) | |
3046 | and then In_Instance | |
3047 | and then Present (Full_View (Type_2)) | |
3048 | and then Base_Types_Match (Type_1, Full_View (Type_2)) | |
3049 | then | |
3050 | return Ctype <= Mode_Conformant | |
3051 | or else Subtypes_Statically_Match (Type_1, Full_View (Type_2)); | |
996ae0b0 RK |
3052 | end if; |
3053 | ||
3054 | -- Test anonymous access type case. For this case, static subtype | |
3055 | -- matching is required for mode conformance (RM 6.3.1(15)) | |
3056 | ||
3057 | if Ekind (Type_1) = E_Anonymous_Access_Type | |
3058 | and then Ekind (Type_2) = E_Anonymous_Access_Type | |
3059 | then | |
3060 | declare | |
3061 | Desig_1 : Entity_Id; | |
3062 | Desig_2 : Entity_Id; | |
3063 | ||
3064 | begin | |
3065 | Desig_1 := Directly_Designated_Type (Type_1); | |
3066 | ||
3067 | -- An access parameter can designate an incomplete type. | |
3068 | ||
3069 | if Ekind (Desig_1) = E_Incomplete_Type | |
3070 | and then Present (Full_View (Desig_1)) | |
3071 | then | |
3072 | Desig_1 := Full_View (Desig_1); | |
3073 | end if; | |
3074 | ||
3075 | Desig_2 := Directly_Designated_Type (Type_2); | |
3076 | ||
3077 | if Ekind (Desig_2) = E_Incomplete_Type | |
3078 | and then Present (Full_View (Desig_2)) | |
3079 | then | |
3080 | Desig_2 := Full_View (Desig_2); | |
3081 | end if; | |
3082 | ||
3083 | -- The context is an instance association for a formal | |
3084 | -- access-to-subprogram type; formal access parameter | |
3085 | -- designated types require mapping because they may | |
3086 | -- denote other formal parameters of the generic unit. | |
3087 | ||
3088 | if Get_Inst then | |
3089 | Desig_1 := Get_Instance_Of (Desig_1); | |
3090 | Desig_2 := Get_Instance_Of (Desig_2); | |
3091 | end if; | |
3092 | ||
3093 | -- It is possible for a Class_Wide_Type to be introduced for | |
3094 | -- an incomplete type, in which case there is a separate class_ | |
3095 | -- wide type for the full view. The types conform if their | |
3096 | -- Etypes conform, i.e. one may be the full view of the other. | |
3097 | -- This can only happen in the context of an access parameter, | |
3098 | -- other uses of an incomplete Class_Wide_Type are illegal. | |
3099 | ||
fbf5a39b AC |
3100 | if Is_Class_Wide_Type (Desig_1) |
3101 | and then Is_Class_Wide_Type (Desig_2) | |
996ae0b0 RK |
3102 | then |
3103 | return | |
fbf5a39b AC |
3104 | Conforming_Types |
3105 | (Etype (Base_Type (Desig_1)), | |
3106 | Etype (Base_Type (Desig_2)), Ctype); | |
996ae0b0 RK |
3107 | else |
3108 | return Base_Type (Desig_1) = Base_Type (Desig_2) | |
3109 | and then (Ctype = Type_Conformant | |
3110 | or else | |
3111 | Subtypes_Statically_Match (Desig_1, Desig_2)); | |
3112 | end if; | |
3113 | end; | |
3114 | ||
3115 | -- Otherwise definitely no match | |
3116 | ||
3117 | else | |
3118 | return False; | |
3119 | end if; | |
3120 | ||
3121 | end Conforming_Types; | |
3122 | ||
3123 | -------------------------- | |
3124 | -- Create_Extra_Formals -- | |
3125 | -------------------------- | |
3126 | ||
3127 | procedure Create_Extra_Formals (E : Entity_Id) is | |
3128 | Formal : Entity_Id; | |
996ae0b0 RK |
3129 | Last_Extra : Entity_Id; |
3130 | Formal_Type : Entity_Id; | |
3131 | P_Formal : Entity_Id := Empty; | |
3132 | ||
3133 | function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id; | |
3134 | -- Add an extra formal, associated with the current Formal. The | |
3135 | -- extra formal is added to the list of extra formals, and also | |
3136 | -- returned as the result. These formals are always of mode IN. | |
3137 | ||
fbf5a39b AC |
3138 | ---------------------- |
3139 | -- Add_Extra_Formal -- | |
3140 | ---------------------- | |
3141 | ||
996ae0b0 RK |
3142 | function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id is |
3143 | EF : constant Entity_Id := | |
3144 | Make_Defining_Identifier (Sloc (Formal), | |
3145 | Chars => New_External_Name (Chars (Formal), 'F')); | |
3146 | ||
3147 | begin | |
3148 | -- We never generate extra formals if expansion is not active | |
3149 | -- because we don't need them unless we are generating code. | |
3150 | ||
3151 | if not Expander_Active then | |
3152 | return Empty; | |
3153 | end if; | |
3154 | ||
3155 | -- A little optimization. Never generate an extra formal for | |
3156 | -- the _init operand of an initialization procedure, since it | |
3157 | -- could never be used. | |
3158 | ||
3159 | if Chars (Formal) = Name_uInit then | |
3160 | return Empty; | |
3161 | end if; | |
3162 | ||
3163 | Set_Ekind (EF, E_In_Parameter); | |
3164 | Set_Actual_Subtype (EF, Typ); | |
3165 | Set_Etype (EF, Typ); | |
3166 | Set_Scope (EF, Scope (Formal)); | |
3167 | Set_Mechanism (EF, Default_Mechanism); | |
3168 | Set_Formal_Validity (EF); | |
3169 | ||
3170 | Set_Extra_Formal (Last_Extra, EF); | |
3171 | Last_Extra := EF; | |
3172 | return EF; | |
3173 | end Add_Extra_Formal; | |
3174 | ||
3175 | -- Start of processing for Create_Extra_Formals | |
3176 | ||
3177 | begin | |
3178 | -- If this is a derived subprogram then the subtypes of the | |
3179 | -- parent subprogram's formal parameters will be used to | |
3180 | -- to determine the need for extra formals. | |
3181 | ||
3182 | if Is_Overloadable (E) and then Present (Alias (E)) then | |
3183 | P_Formal := First_Formal (Alias (E)); | |
3184 | end if; | |
3185 | ||
3186 | Last_Extra := Empty; | |
3187 | Formal := First_Formal (E); | |
3188 | while Present (Formal) loop | |
3189 | Last_Extra := Formal; | |
3190 | Next_Formal (Formal); | |
3191 | end loop; | |
3192 | ||
3193 | -- If Extra_formals where already created, don't do it again | |
3194 | -- This situation may arise for subprogram types created as part | |
3195 | -- of dispatching calls (see Expand_Dispatch_Call) | |
3196 | ||
3197 | if Present (Last_Extra) and then | |
3198 | Present (Extra_Formal (Last_Extra)) | |
3199 | then | |
3200 | return; | |
3201 | end if; | |
3202 | ||
3203 | Formal := First_Formal (E); | |
3204 | ||
3205 | while Present (Formal) loop | |
3206 | ||
3207 | -- Create extra formal for supporting the attribute 'Constrained. | |
3208 | -- The case of a private type view without discriminants also | |
3209 | -- requires the extra formal if the underlying type has defaulted | |
3210 | -- discriminants. | |
3211 | ||
3212 | if Ekind (Formal) /= E_In_Parameter then | |
3213 | if Present (P_Formal) then | |
3214 | Formal_Type := Etype (P_Formal); | |
3215 | else | |
3216 | Formal_Type := Etype (Formal); | |
3217 | end if; | |
3218 | ||
3219 | if not Has_Discriminants (Formal_Type) | |
3220 | and then Ekind (Formal_Type) in Private_Kind | |
3221 | and then Present (Underlying_Type (Formal_Type)) | |
3222 | then | |
3223 | Formal_Type := Underlying_Type (Formal_Type); | |
3224 | end if; | |
3225 | ||
3226 | if Has_Discriminants (Formal_Type) | |
3227 | and then | |
3228 | ((not Is_Constrained (Formal_Type) | |
3229 | and then not Is_Indefinite_Subtype (Formal_Type)) | |
3230 | or else Present (Extra_Formal (Formal))) | |
3231 | then | |
3232 | Set_Extra_Constrained | |
3233 | (Formal, Add_Extra_Formal (Standard_Boolean)); | |
3234 | end if; | |
3235 | end if; | |
3236 | ||
3237 | -- Create extra formal for supporting accessibility checking | |
3238 | ||
3239 | -- This is suppressed if we specifically suppress accessibility | |
fbf5a39b AC |
3240 | -- checks at the pacage level for either the subprogram, or the |
3241 | -- package in which it resides. However, we do not suppress it | |
3242 | -- simply if the scope has accessibility checks suppressed, since | |
3243 | -- this could cause trouble when clients are compiled with a | |
3244 | -- different suppression setting. The explicit checks at the | |
3245 | -- package level are safe from this point of view. | |
996ae0b0 RK |
3246 | |
3247 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type | |
3248 | and then not | |
fbf5a39b | 3249 | (Explicit_Suppress (E, Accessibility_Check) |
996ae0b0 | 3250 | or else |
fbf5a39b | 3251 | Explicit_Suppress (Scope (E), Accessibility_Check)) |
996ae0b0 RK |
3252 | and then |
3253 | (not Present (P_Formal) | |
3254 | or else Present (Extra_Accessibility (P_Formal))) | |
3255 | then | |
3256 | -- Temporary kludge: for now we avoid creating the extra | |
3257 | -- formal for access parameters of protected operations | |
3258 | -- because of problem with the case of internal protected | |
3259 | -- calls. ??? | |
3260 | ||
3261 | if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition | |
3262 | and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body | |
3263 | then | |
3264 | Set_Extra_Accessibility | |
3265 | (Formal, Add_Extra_Formal (Standard_Natural)); | |
3266 | end if; | |
3267 | end if; | |
3268 | ||
3269 | if Present (P_Formal) then | |
3270 | Next_Formal (P_Formal); | |
3271 | end if; | |
3272 | ||
996ae0b0 RK |
3273 | Next_Formal (Formal); |
3274 | end loop; | |
3275 | end Create_Extra_Formals; | |
3276 | ||
3277 | ----------------------------- | |
3278 | -- Enter_Overloaded_Entity -- | |
3279 | ----------------------------- | |
3280 | ||
3281 | procedure Enter_Overloaded_Entity (S : Entity_Id) is | |
3282 | E : Entity_Id := Current_Entity_In_Scope (S); | |
3283 | C_E : Entity_Id := Current_Entity (S); | |
3284 | ||
3285 | begin | |
3286 | if Present (E) then | |
3287 | Set_Has_Homonym (E); | |
3288 | Set_Has_Homonym (S); | |
3289 | end if; | |
3290 | ||
3291 | Set_Is_Immediately_Visible (S); | |
3292 | Set_Scope (S, Current_Scope); | |
3293 | ||
3294 | -- Chain new entity if front of homonym in current scope, so that | |
3295 | -- homonyms are contiguous. | |
3296 | ||
3297 | if Present (E) | |
3298 | and then E /= C_E | |
3299 | then | |
3300 | while Homonym (C_E) /= E loop | |
3301 | C_E := Homonym (C_E); | |
3302 | end loop; | |
3303 | ||
3304 | Set_Homonym (C_E, S); | |
3305 | ||
3306 | else | |
3307 | E := C_E; | |
3308 | Set_Current_Entity (S); | |
3309 | end if; | |
3310 | ||
3311 | Set_Homonym (S, E); | |
3312 | ||
3313 | Append_Entity (S, Current_Scope); | |
3314 | Set_Public_Status (S); | |
3315 | ||
3316 | if Debug_Flag_E then | |
3317 | Write_Str ("New overloaded entity chain: "); | |
3318 | Write_Name (Chars (S)); | |
3319 | E := S; | |
3320 | ||
3321 | while Present (E) loop | |
3322 | Write_Str (" "); Write_Int (Int (E)); | |
3323 | E := Homonym (E); | |
3324 | end loop; | |
3325 | ||
3326 | Write_Eol; | |
3327 | end if; | |
3328 | ||
3329 | -- Generate warning for hiding | |
3330 | ||
3331 | if Warn_On_Hiding | |
3332 | and then Comes_From_Source (S) | |
3333 | and then In_Extended_Main_Source_Unit (S) | |
3334 | then | |
3335 | E := S; | |
3336 | loop | |
3337 | E := Homonym (E); | |
3338 | exit when No (E); | |
3339 | ||
3340 | -- Warn unless genuine overloading | |
3341 | ||
3342 | if (not Is_Overloadable (E)) | |
3343 | or else Subtype_Conformant (E, S) | |
3344 | then | |
3345 | Error_Msg_Sloc := Sloc (E); | |
3346 | Error_Msg_N ("declaration of & hides one#?", S); | |
3347 | end if; | |
3348 | end loop; | |
3349 | end if; | |
3350 | end Enter_Overloaded_Entity; | |
3351 | ||
3352 | ----------------------------- | |
3353 | -- Find_Corresponding_Spec -- | |
3354 | ----------------------------- | |
3355 | ||
3356 | function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is | |
3357 | Spec : constant Node_Id := Specification (N); | |
3358 | Designator : constant Entity_Id := Defining_Entity (Spec); | |
3359 | ||
3360 | E : Entity_Id; | |
3361 | ||
3362 | begin | |
3363 | E := Current_Entity (Designator); | |
3364 | ||
3365 | while Present (E) loop | |
3366 | ||
3367 | -- We are looking for a matching spec. It must have the same scope, | |
3368 | -- and the same name, and either be type conformant, or be the case | |
3369 | -- of a library procedure spec and its body (which belong to one | |
3370 | -- another regardless of whether they are type conformant or not). | |
3371 | ||
3372 | if Scope (E) = Current_Scope then | |
fbf5a39b AC |
3373 | if Current_Scope = Standard_Standard |
3374 | or else (Ekind (E) = Ekind (Designator) | |
3375 | and then Type_Conformant (E, Designator)) | |
996ae0b0 RK |
3376 | then |
3377 | -- Within an instantiation, we know that spec and body are | |
3378 | -- subtype conformant, because they were subtype conformant | |
3379 | -- in the generic. We choose the subtype-conformant entity | |
3380 | -- here as well, to resolve spurious ambiguities in the | |
3381 | -- instance that were not present in the generic (i.e. when | |
3382 | -- two different types are given the same actual). If we are | |
3383 | -- looking for a spec to match a body, full conformance is | |
3384 | -- expected. | |
3385 | ||
3386 | if In_Instance then | |
3387 | Set_Convention (Designator, Convention (E)); | |
3388 | ||
3389 | if Nkind (N) = N_Subprogram_Body | |
3390 | and then Present (Homonym (E)) | |
3391 | and then not Fully_Conformant (E, Designator) | |
3392 | then | |
3393 | goto Next_Entity; | |
3394 | ||
3395 | elsif not Subtype_Conformant (E, Designator) then | |
3396 | goto Next_Entity; | |
3397 | end if; | |
3398 | end if; | |
3399 | ||
3400 | if not Has_Completion (E) then | |
3401 | ||
3402 | if Nkind (N) /= N_Subprogram_Body_Stub then | |
3403 | Set_Corresponding_Spec (N, E); | |
3404 | end if; | |
3405 | ||
3406 | Set_Has_Completion (E); | |
3407 | return E; | |
3408 | ||
3409 | elsif Nkind (Parent (N)) = N_Subunit then | |
3410 | ||
3411 | -- If this is the proper body of a subunit, the completion | |
3412 | -- flag is set when analyzing the stub. | |
3413 | ||
3414 | return E; | |
3415 | ||
3416 | -- If body already exists, this is an error unless the | |
3417 | -- previous declaration is the implicit declaration of | |
3418 | -- a derived subprogram, or this is a spurious overloading | |
3419 | -- in an instance. | |
3420 | ||
3421 | elsif No (Alias (E)) | |
3422 | and then not Is_Intrinsic_Subprogram (E) | |
3423 | and then not In_Instance | |
3424 | then | |
3425 | Error_Msg_Sloc := Sloc (E); | |
07fc65c4 GB |
3426 | if Is_Imported (E) then |
3427 | Error_Msg_NE | |
3428 | ("body not allowed for imported subprogram & declared#", | |
3429 | N, E); | |
3430 | else | |
3431 | Error_Msg_NE ("duplicate body for & declared#", N, E); | |
3432 | end if; | |
996ae0b0 RK |
3433 | end if; |
3434 | ||
3435 | elsif Is_Child_Unit (E) | |
3436 | and then | |
3437 | Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body | |
3438 | and then | |
3439 | Nkind (Parent (Unit_Declaration_Node (Designator))) | |
3440 | = N_Compilation_Unit | |
3441 | then | |
3442 | ||
3443 | -- Child units cannot be overloaded, so a conformance mismatch | |
3444 | -- between body and a previous spec is an error. | |
3445 | ||
3446 | Error_Msg_N | |
3447 | ("body of child unit does not match previous declaration", N); | |
3448 | end if; | |
3449 | end if; | |
3450 | ||
3451 | <<Next_Entity>> | |
3452 | E := Homonym (E); | |
3453 | end loop; | |
3454 | ||
3455 | -- On exit, we know that no previous declaration of subprogram exists | |
3456 | ||
3457 | return Empty; | |
3458 | end Find_Corresponding_Spec; | |
3459 | ||
3460 | ---------------------- | |
3461 | -- Fully_Conformant -- | |
3462 | ---------------------- | |
3463 | ||
3464 | function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is | |
3465 | Result : Boolean; | |
3466 | ||
3467 | begin | |
3468 | Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result); | |
3469 | return Result; | |
3470 | end Fully_Conformant; | |
3471 | ||
3472 | ---------------------------------- | |
3473 | -- Fully_Conformant_Expressions -- | |
3474 | ---------------------------------- | |
3475 | ||
3476 | function Fully_Conformant_Expressions | |
3477 | (Given_E1 : Node_Id; | |
3478 | Given_E2 : Node_Id) | |
3479 | return Boolean | |
3480 | is | |
3481 | E1 : constant Node_Id := Original_Node (Given_E1); | |
3482 | E2 : constant Node_Id := Original_Node (Given_E2); | |
3483 | -- We always test conformance on original nodes, since it is possible | |
3484 | -- for analysis and/or expansion to make things look as though they | |
3485 | -- conform when they do not, e.g. by converting 1+2 into 3. | |
3486 | ||
3487 | function FCE (Given_E1, Given_E2 : Node_Id) return Boolean | |
3488 | renames Fully_Conformant_Expressions; | |
3489 | ||
3490 | function FCL (L1, L2 : List_Id) return Boolean; | |
3491 | -- Compare elements of two lists for conformance. Elements have to | |
3492 | -- be conformant, and actuals inserted as default parameters do not | |
3493 | -- match explicit actuals with the same value. | |
3494 | ||
3495 | function FCO (Op_Node, Call_Node : Node_Id) return Boolean; | |
3496 | -- Compare an operator node with a function call. | |
3497 | ||
3498 | --------- | |
3499 | -- FCL -- | |
3500 | --------- | |
3501 | ||
3502 | function FCL (L1, L2 : List_Id) return Boolean is | |
3503 | N1, N2 : Node_Id; | |
3504 | ||
3505 | begin | |
3506 | if L1 = No_List then | |
3507 | N1 := Empty; | |
3508 | else | |
3509 | N1 := First (L1); | |
3510 | end if; | |
3511 | ||
3512 | if L2 = No_List then | |
3513 | N2 := Empty; | |
3514 | else | |
3515 | N2 := First (L2); | |
3516 | end if; | |
3517 | ||
3518 | -- Compare two lists, skipping rewrite insertions (we want to | |
3519 | -- compare the original trees, not the expanded versions!) | |
3520 | ||
3521 | loop | |
3522 | if Is_Rewrite_Insertion (N1) then | |
3523 | Next (N1); | |
3524 | elsif Is_Rewrite_Insertion (N2) then | |
3525 | Next (N2); | |
3526 | elsif No (N1) then | |
3527 | return No (N2); | |
3528 | elsif No (N2) then | |
3529 | return False; | |
3530 | elsif not FCE (N1, N2) then | |
3531 | return False; | |
3532 | else | |
3533 | Next (N1); | |
3534 | Next (N2); | |
3535 | end if; | |
3536 | end loop; | |
3537 | end FCL; | |
3538 | ||
3539 | --------- | |
3540 | -- FCO -- | |
3541 | --------- | |
3542 | ||
3543 | function FCO (Op_Node, Call_Node : Node_Id) return Boolean is | |
3544 | Actuals : constant List_Id := Parameter_Associations (Call_Node); | |
3545 | Act : Node_Id; | |
3546 | ||
3547 | begin | |
3548 | if No (Actuals) | |
3549 | or else Entity (Op_Node) /= Entity (Name (Call_Node)) | |
3550 | then | |
3551 | return False; | |
3552 | ||
3553 | else | |
3554 | Act := First (Actuals); | |
3555 | ||
3556 | if Nkind (Op_Node) in N_Binary_Op then | |
3557 | ||
3558 | if not FCE (Left_Opnd (Op_Node), Act) then | |
3559 | return False; | |
3560 | end if; | |
3561 | ||
3562 | Next (Act); | |
3563 | end if; | |
3564 | ||
3565 | return Present (Act) | |
3566 | and then FCE (Right_Opnd (Op_Node), Act) | |
3567 | and then No (Next (Act)); | |
3568 | end if; | |
3569 | end FCO; | |
3570 | ||
3571 | -- Start of processing for Fully_Conformant_Expressions | |
3572 | ||
3573 | begin | |
3574 | -- Non-conformant if paren count does not match. Note: if some idiot | |
3575 | -- complains that we don't do this right for more than 3 levels of | |
3576 | -- parentheses, they will be treated with the respect they deserve :-) | |
3577 | ||
3578 | if Paren_Count (E1) /= Paren_Count (E2) then | |
3579 | return False; | |
3580 | ||
3581 | -- If same entities are referenced, then they are conformant | |
3582 | -- even if they have different forms (RM 8.3.1(19-20)). | |
3583 | ||
3584 | elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then | |
3585 | if Present (Entity (E1)) then | |
3586 | return Entity (E1) = Entity (E2) | |
3587 | or else (Chars (Entity (E1)) = Chars (Entity (E2)) | |
3588 | and then Ekind (Entity (E1)) = E_Discriminant | |
3589 | and then Ekind (Entity (E2)) = E_In_Parameter); | |
3590 | ||
3591 | elsif Nkind (E1) = N_Expanded_Name | |
3592 | and then Nkind (E2) = N_Expanded_Name | |
3593 | and then Nkind (Selector_Name (E1)) = N_Character_Literal | |
3594 | and then Nkind (Selector_Name (E2)) = N_Character_Literal | |
3595 | then | |
3596 | return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2)); | |
3597 | ||
3598 | else | |
3599 | -- Identifiers in component associations don't always have | |
3600 | -- entities, but their names must conform. | |
3601 | ||
3602 | return Nkind (E1) = N_Identifier | |
3603 | and then Nkind (E2) = N_Identifier | |
3604 | and then Chars (E1) = Chars (E2); | |
3605 | end if; | |
3606 | ||
3607 | elsif Nkind (E1) = N_Character_Literal | |
3608 | and then Nkind (E2) = N_Expanded_Name | |
3609 | then | |
3610 | return Nkind (Selector_Name (E2)) = N_Character_Literal | |
3611 | and then Chars (E1) = Chars (Selector_Name (E2)); | |
3612 | ||
3613 | elsif Nkind (E2) = N_Character_Literal | |
3614 | and then Nkind (E1) = N_Expanded_Name | |
3615 | then | |
3616 | return Nkind (Selector_Name (E1)) = N_Character_Literal | |
3617 | and then Chars (E2) = Chars (Selector_Name (E1)); | |
3618 | ||
3619 | elsif Nkind (E1) in N_Op | |
3620 | and then Nkind (E2) = N_Function_Call | |
3621 | then | |
3622 | return FCO (E1, E2); | |
3623 | ||
3624 | elsif Nkind (E2) in N_Op | |
3625 | and then Nkind (E1) = N_Function_Call | |
3626 | then | |
3627 | return FCO (E2, E1); | |
3628 | ||
3629 | -- Otherwise we must have the same syntactic entity | |
3630 | ||
3631 | elsif Nkind (E1) /= Nkind (E2) then | |
3632 | return False; | |
3633 | ||
3634 | -- At this point, we specialize by node type | |
3635 | ||
3636 | else | |
3637 | case Nkind (E1) is | |
3638 | ||
3639 | when N_Aggregate => | |
3640 | return | |
3641 | FCL (Expressions (E1), Expressions (E2)) | |
3642 | and then FCL (Component_Associations (E1), | |
3643 | Component_Associations (E2)); | |
3644 | ||
3645 | when N_Allocator => | |
3646 | if Nkind (Expression (E1)) = N_Qualified_Expression | |
3647 | or else | |
3648 | Nkind (Expression (E2)) = N_Qualified_Expression | |
3649 | then | |
3650 | return FCE (Expression (E1), Expression (E2)); | |
3651 | ||
3652 | -- Check that the subtype marks and any constraints | |
3653 | -- are conformant | |
3654 | ||
3655 | else | |
3656 | declare | |
3657 | Indic1 : constant Node_Id := Expression (E1); | |
3658 | Indic2 : constant Node_Id := Expression (E2); | |
3659 | Elt1 : Node_Id; | |
3660 | Elt2 : Node_Id; | |
3661 | ||
3662 | begin | |
3663 | if Nkind (Indic1) /= N_Subtype_Indication then | |
3664 | return | |
3665 | Nkind (Indic2) /= N_Subtype_Indication | |
3666 | and then Entity (Indic1) = Entity (Indic2); | |
3667 | ||
3668 | elsif Nkind (Indic2) /= N_Subtype_Indication then | |
3669 | return | |
3670 | Nkind (Indic1) /= N_Subtype_Indication | |
3671 | and then Entity (Indic1) = Entity (Indic2); | |
3672 | ||
3673 | else | |
3674 | if Entity (Subtype_Mark (Indic1)) /= | |
3675 | Entity (Subtype_Mark (Indic2)) | |
3676 | then | |
3677 | return False; | |
3678 | end if; | |
3679 | ||
3680 | Elt1 := First (Constraints (Constraint (Indic1))); | |
3681 | Elt2 := First (Constraints (Constraint (Indic2))); | |
3682 | ||
3683 | while Present (Elt1) and then Present (Elt2) loop | |
3684 | if not FCE (Elt1, Elt2) then | |
3685 | return False; | |
3686 | end if; | |
3687 | ||
3688 | Next (Elt1); | |
3689 | Next (Elt2); | |
3690 | end loop; | |
3691 | ||
3692 | return True; | |
3693 | end if; | |
3694 | end; | |
3695 | end if; | |
3696 | ||
3697 | when N_Attribute_Reference => | |
3698 | return | |
3699 | Attribute_Name (E1) = Attribute_Name (E2) | |
3700 | and then FCL (Expressions (E1), Expressions (E2)); | |
3701 | ||
3702 | when N_Binary_Op => | |
3703 | return | |
3704 | Entity (E1) = Entity (E2) | |
3705 | and then FCE (Left_Opnd (E1), Left_Opnd (E2)) | |
3706 | and then FCE (Right_Opnd (E1), Right_Opnd (E2)); | |
3707 | ||
3708 | when N_And_Then | N_Or_Else | N_In | N_Not_In => | |
3709 | return | |
3710 | FCE (Left_Opnd (E1), Left_Opnd (E2)) | |
3711 | and then | |
3712 | FCE (Right_Opnd (E1), Right_Opnd (E2)); | |
3713 | ||
3714 | when N_Character_Literal => | |
3715 | return | |
3716 | Char_Literal_Value (E1) = Char_Literal_Value (E2); | |
3717 | ||
3718 | when N_Component_Association => | |
3719 | return | |
3720 | FCL (Choices (E1), Choices (E2)) | |
3721 | and then FCE (Expression (E1), Expression (E2)); | |
3722 | ||
3723 | when N_Conditional_Expression => | |
3724 | return | |
3725 | FCL (Expressions (E1), Expressions (E2)); | |
3726 | ||
3727 | when N_Explicit_Dereference => | |
3728 | return | |
3729 | FCE (Prefix (E1), Prefix (E2)); | |
3730 | ||
3731 | when N_Extension_Aggregate => | |
3732 | return | |
3733 | FCL (Expressions (E1), Expressions (E2)) | |
3734 | and then Null_Record_Present (E1) = | |
3735 | Null_Record_Present (E2) | |
3736 | and then FCL (Component_Associations (E1), | |
3737 | Component_Associations (E2)); | |
3738 | ||
3739 | when N_Function_Call => | |
3740 | return | |
3741 | FCE (Name (E1), Name (E2)) | |
3742 | and then FCL (Parameter_Associations (E1), | |
3743 | Parameter_Associations (E2)); | |
3744 | ||
3745 | when N_Indexed_Component => | |
3746 | return | |
3747 | FCE (Prefix (E1), Prefix (E2)) | |
3748 | and then FCL (Expressions (E1), Expressions (E2)); | |
3749 | ||
3750 | when N_Integer_Literal => | |
3751 | return (Intval (E1) = Intval (E2)); | |
3752 | ||
3753 | when N_Null => | |
3754 | return True; | |
3755 | ||
3756 | when N_Operator_Symbol => | |
3757 | return | |
3758 | Chars (E1) = Chars (E2); | |
3759 | ||
3760 | when N_Others_Choice => | |
3761 | return True; | |
3762 | ||
3763 | when N_Parameter_Association => | |
3764 | return | |
996ae0b0 RK |
3765 | Chars (Selector_Name (E1)) = Chars (Selector_Name (E2)) |
3766 | and then FCE (Explicit_Actual_Parameter (E1), | |
3767 | Explicit_Actual_Parameter (E2)); | |
3768 | ||
3769 | when N_Qualified_Expression => | |
3770 | return | |
3771 | FCE (Subtype_Mark (E1), Subtype_Mark (E2)) | |
3772 | and then FCE (Expression (E1), Expression (E2)); | |
3773 | ||
3774 | when N_Range => | |
3775 | return | |
3776 | FCE (Low_Bound (E1), Low_Bound (E2)) | |
3777 | and then FCE (High_Bound (E1), High_Bound (E2)); | |
3778 | ||
3779 | when N_Real_Literal => | |
3780 | return (Realval (E1) = Realval (E2)); | |
3781 | ||
3782 | when N_Selected_Component => | |
3783 | return | |
3784 | FCE (Prefix (E1), Prefix (E2)) | |
3785 | and then FCE (Selector_Name (E1), Selector_Name (E2)); | |
3786 | ||
3787 | when N_Slice => | |
3788 | return | |
3789 | FCE (Prefix (E1), Prefix (E2)) | |
3790 | and then FCE (Discrete_Range (E1), Discrete_Range (E2)); | |
3791 | ||
3792 | when N_String_Literal => | |
3793 | declare | |
3794 | S1 : constant String_Id := Strval (E1); | |
3795 | S2 : constant String_Id := Strval (E2); | |
3796 | L1 : constant Nat := String_Length (S1); | |
3797 | L2 : constant Nat := String_Length (S2); | |
3798 | ||
3799 | begin | |
3800 | if L1 /= L2 then | |
3801 | return False; | |
3802 | ||
3803 | else | |
3804 | for J in 1 .. L1 loop | |
3805 | if Get_String_Char (S1, J) /= | |
3806 | Get_String_Char (S2, J) | |
3807 | then | |
3808 | return False; | |
3809 | end if; | |
3810 | end loop; | |
3811 | ||
3812 | return True; | |
3813 | end if; | |
3814 | end; | |
3815 | ||
3816 | when N_Type_Conversion => | |
3817 | return | |
3818 | FCE (Subtype_Mark (E1), Subtype_Mark (E2)) | |
3819 | and then FCE (Expression (E1), Expression (E2)); | |
3820 | ||
3821 | when N_Unary_Op => | |
3822 | return | |
3823 | Entity (E1) = Entity (E2) | |
3824 | and then FCE (Right_Opnd (E1), Right_Opnd (E2)); | |
3825 | ||
3826 | when N_Unchecked_Type_Conversion => | |
3827 | return | |
3828 | FCE (Subtype_Mark (E1), Subtype_Mark (E2)) | |
3829 | and then FCE (Expression (E1), Expression (E2)); | |
3830 | ||
3831 | -- All other node types cannot appear in this context. Strictly | |
3832 | -- we should raise a fatal internal error. Instead we just ignore | |
3833 | -- the nodes. This means that if anyone makes a mistake in the | |
3834 | -- expander and mucks an expression tree irretrievably, the | |
3835 | -- result will be a failure to detect a (probably very obscure) | |
3836 | -- case of non-conformance, which is better than bombing on some | |
3837 | -- case where two expressions do in fact conform. | |
3838 | ||
3839 | when others => | |
3840 | return True; | |
3841 | ||
3842 | end case; | |
3843 | end if; | |
3844 | end Fully_Conformant_Expressions; | |
3845 | ||
fbf5a39b AC |
3846 | ---------------------------------------- |
3847 | -- Fully_Conformant_Discrete_Subtypes -- | |
3848 | ---------------------------------------- | |
3849 | ||
3850 | function Fully_Conformant_Discrete_Subtypes | |
3851 | (Given_S1 : Node_Id; | |
3852 | Given_S2 : Node_Id) | |
3853 | return Boolean | |
3854 | is | |
3855 | S1 : constant Node_Id := Original_Node (Given_S1); | |
3856 | S2 : constant Node_Id := Original_Node (Given_S2); | |
3857 | ||
3858 | function Conforming_Bounds (B1, B2 : Node_Id) return Boolean; | |
3859 | -- Special-case for a bound given by a discriminant, which in the | |
3860 | -- body is replaced with the discriminal of the enclosing type. | |
3861 | ||
3862 | function Conforming_Ranges (R1, R2 : Node_Id) return Boolean; | |
3863 | -- Check both bounds. | |
3864 | ||
3865 | function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is | |
3866 | begin | |
3867 | if Is_Entity_Name (B1) | |
3868 | and then Is_Entity_Name (B2) | |
3869 | and then Ekind (Entity (B1)) = E_Discriminant | |
3870 | then | |
3871 | return Chars (B1) = Chars (B2); | |
3872 | ||
3873 | else | |
3874 | return Fully_Conformant_Expressions (B1, B2); | |
3875 | end if; | |
3876 | end Conforming_Bounds; | |
3877 | ||
3878 | function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is | |
3879 | begin | |
3880 | return | |
3881 | Conforming_Bounds (Low_Bound (R1), Low_Bound (R2)) | |
3882 | and then | |
3883 | Conforming_Bounds (High_Bound (R1), High_Bound (R2)); | |
3884 | end Conforming_Ranges; | |
3885 | ||
3886 | -- Start of processing for Fully_Conformant_Discrete_Subtypes | |
3887 | ||
3888 | begin | |
3889 | if Nkind (S1) /= Nkind (S2) then | |
3890 | return False; | |
3891 | ||
3892 | elsif Is_Entity_Name (S1) then | |
3893 | return Entity (S1) = Entity (S2); | |
3894 | ||
3895 | elsif Nkind (S1) = N_Range then | |
3896 | return Conforming_Ranges (S1, S2); | |
3897 | ||
3898 | elsif Nkind (S1) = N_Subtype_Indication then | |
3899 | return | |
3900 | Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2)) | |
3901 | and then | |
3902 | Conforming_Ranges | |
3903 | (Range_Expression (Constraint (S1)), | |
3904 | Range_Expression (Constraint (S2))); | |
3905 | else | |
3906 | return True; | |
3907 | end if; | |
3908 | end Fully_Conformant_Discrete_Subtypes; | |
3909 | ||
996ae0b0 RK |
3910 | -------------------- |
3911 | -- Install_Entity -- | |
3912 | -------------------- | |
3913 | ||
3914 | procedure Install_Entity (E : Entity_Id) is | |
3915 | Prev : constant Entity_Id := Current_Entity (E); | |
3916 | ||
3917 | begin | |
3918 | Set_Is_Immediately_Visible (E); | |
3919 | Set_Current_Entity (E); | |
3920 | Set_Homonym (E, Prev); | |
3921 | end Install_Entity; | |
3922 | ||
3923 | --------------------- | |
3924 | -- Install_Formals -- | |
3925 | --------------------- | |
3926 | ||
3927 | procedure Install_Formals (Id : Entity_Id) is | |
3928 | F : Entity_Id; | |
3929 | ||
3930 | begin | |
3931 | F := First_Formal (Id); | |
3932 | ||
3933 | while Present (F) loop | |
3934 | Install_Entity (F); | |
3935 | Next_Formal (F); | |
3936 | end loop; | |
3937 | end Install_Formals; | |
3938 | ||
3939 | --------------------------------- | |
3940 | -- Is_Non_Overriding_Operation -- | |
3941 | --------------------------------- | |
3942 | ||
3943 | function Is_Non_Overriding_Operation | |
3944 | (Prev_E : Entity_Id; | |
3945 | New_E : Entity_Id) | |
3946 | return Boolean | |
3947 | is | |
3948 | Formal : Entity_Id; | |
3949 | F_Typ : Entity_Id; | |
3950 | G_Typ : Entity_Id := Empty; | |
3951 | ||
3952 | function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id; | |
3953 | -- If F_Type is a derived type associated with a generic actual | |
3954 | -- subtype, then return its Generic_Parent_Type attribute, else | |
3955 | -- return Empty. | |
3956 | ||
3957 | function Types_Correspond | |
3958 | (P_Type : Entity_Id; | |
3959 | N_Type : Entity_Id) | |
3960 | return Boolean; | |
3961 | -- Returns true if and only if the types (or designated types | |
3962 | -- in the case of anonymous access types) are the same or N_Type | |
3963 | -- is derived directly or indirectly from P_Type. | |
3964 | ||
3965 | ----------------------------- | |
3966 | -- Get_Generic_Parent_Type -- | |
3967 | ----------------------------- | |
3968 | ||
3969 | function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is | |
3970 | G_Typ : Entity_Id; | |
3971 | Indic : Node_Id; | |
3972 | ||
3973 | begin | |
3974 | if Is_Derived_Type (F_Typ) | |
3975 | and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration | |
3976 | then | |
3977 | -- The tree must be traversed to determine the parent | |
3978 | -- subtype in the generic unit, which unfortunately isn't | |
3979 | -- always available via semantic attributes. ??? | |
3980 | -- (Note: The use of Original_Node is needed for cases | |
3981 | -- where a full derived type has been rewritten.) | |
3982 | ||
3983 | Indic := Subtype_Indication | |
3984 | (Type_Definition (Original_Node (Parent (F_Typ)))); | |
3985 | ||
3986 | if Nkind (Indic) = N_Subtype_Indication then | |
3987 | G_Typ := Entity (Subtype_Mark (Indic)); | |
3988 | else | |
3989 | G_Typ := Entity (Indic); | |
3990 | end if; | |
3991 | ||
3992 | if Nkind (Parent (G_Typ)) = N_Subtype_Declaration | |
3993 | and then Present (Generic_Parent_Type (Parent (G_Typ))) | |
3994 | then | |
3995 | return Generic_Parent_Type (Parent (G_Typ)); | |
3996 | end if; | |
3997 | end if; | |
3998 | ||
3999 | return Empty; | |
4000 | end Get_Generic_Parent_Type; | |
4001 | ||
4002 | ---------------------- | |
4003 | -- Types_Correspond -- | |
4004 | ---------------------- | |
4005 | ||
4006 | function Types_Correspond | |
4007 | (P_Type : Entity_Id; | |
4008 | N_Type : Entity_Id) | |
4009 | return Boolean | |
4010 | is | |
4011 | Prev_Type : Entity_Id := Base_Type (P_Type); | |
4012 | New_Type : Entity_Id := Base_Type (N_Type); | |
4013 | ||
4014 | begin | |
4015 | if Ekind (Prev_Type) = E_Anonymous_Access_Type then | |
4016 | Prev_Type := Designated_Type (Prev_Type); | |
4017 | end if; | |
4018 | ||
4019 | if Ekind (New_Type) = E_Anonymous_Access_Type then | |
4020 | New_Type := Designated_Type (New_Type); | |
4021 | end if; | |
4022 | ||
4023 | if Prev_Type = New_Type then | |
4024 | return True; | |
4025 | ||
4026 | elsif not Is_Class_Wide_Type (New_Type) then | |
4027 | while Etype (New_Type) /= New_Type loop | |
4028 | New_Type := Etype (New_Type); | |
4029 | if New_Type = Prev_Type then | |
4030 | return True; | |
4031 | end if; | |
4032 | end loop; | |
4033 | end if; | |
4034 | return False; | |
4035 | end Types_Correspond; | |
4036 | ||
4037 | -- Start of processing for Is_Non_Overriding_Operation | |
4038 | ||
4039 | begin | |
4040 | -- In the case where both operations are implicit derived | |
4041 | -- subprograms then neither overrides the other. This can | |
4042 | -- only occur in certain obscure cases (e.g., derivation | |
4043 | -- from homographs created in a generic instantiation). | |
4044 | ||
4045 | if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then | |
4046 | return True; | |
4047 | ||
4048 | elsif Ekind (Current_Scope) = E_Package | |
4049 | and then Is_Generic_Instance (Current_Scope) | |
4050 | and then In_Private_Part (Current_Scope) | |
4051 | and then Comes_From_Source (New_E) | |
4052 | then | |
4053 | -- We examine the formals and result subtype of the inherited | |
4054 | -- operation, to determine whether their type is derived from | |
4055 | -- (the instance of) a generic type. | |
4056 | ||
4057 | Formal := First_Formal (Prev_E); | |
4058 | ||
4059 | while Present (Formal) loop | |
4060 | F_Typ := Base_Type (Etype (Formal)); | |
4061 | ||
4062 | if Ekind (F_Typ) = E_Anonymous_Access_Type then | |
4063 | F_Typ := Designated_Type (F_Typ); | |
4064 | end if; | |
4065 | ||
4066 | G_Typ := Get_Generic_Parent_Type (F_Typ); | |
4067 | ||
4068 | Next_Formal (Formal); | |
4069 | end loop; | |
4070 | ||
4071 | if not Present (G_Typ) and then Ekind (Prev_E) = E_Function then | |
4072 | G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E))); | |
4073 | end if; | |
4074 | ||
4075 | if No (G_Typ) then | |
4076 | return False; | |
4077 | end if; | |
4078 | ||
4079 | -- If the generic type is a private type, then the original | |
4080 | -- operation was not overriding in the generic, because there was | |
4081 | -- no primitive operation to override. | |
4082 | ||
4083 | if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration | |
4084 | and then Nkind (Formal_Type_Definition (Parent (G_Typ))) = | |
4085 | N_Formal_Private_Type_Definition | |
4086 | then | |
4087 | return True; | |
4088 | ||
4089 | -- The generic parent type is the ancestor of a formal derived | |
4090 | -- type declaration. We need to check whether it has a primitive | |
4091 | -- operation that should be overridden by New_E in the generic. | |
4092 | ||
4093 | else | |
4094 | declare | |
4095 | P_Formal : Entity_Id; | |
4096 | N_Formal : Entity_Id; | |
4097 | P_Typ : Entity_Id; | |
4098 | N_Typ : Entity_Id; | |
4099 | P_Prim : Entity_Id; | |
4100 | Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ)); | |
4101 | ||
4102 | begin | |
4103 | while Present (Prim_Elt) loop | |
4104 | P_Prim := Node (Prim_Elt); | |
fbf5a39b | 4105 | |
996ae0b0 RK |
4106 | if Chars (P_Prim) = Chars (New_E) |
4107 | and then Ekind (P_Prim) = Ekind (New_E) | |
4108 | then | |
4109 | P_Formal := First_Formal (P_Prim); | |
4110 | N_Formal := First_Formal (New_E); | |
4111 | while Present (P_Formal) and then Present (N_Formal) loop | |
4112 | P_Typ := Etype (P_Formal); | |
4113 | N_Typ := Etype (N_Formal); | |
4114 | ||
4115 | if not Types_Correspond (P_Typ, N_Typ) then | |
4116 | exit; | |
4117 | end if; | |
4118 | ||
4119 | Next_Entity (P_Formal); | |
4120 | Next_Entity (N_Formal); | |
4121 | end loop; | |
4122 | ||
4123 | -- Found a matching primitive operation belonging to | |
4124 | -- the formal ancestor type, so the new subprogram | |
4125 | -- is overriding. | |
4126 | ||
4127 | if not Present (P_Formal) | |
4128 | and then not Present (N_Formal) | |
4129 | and then (Ekind (New_E) /= E_Function | |
4130 | or else | |
4131 | Types_Correspond | |
4132 | (Etype (P_Prim), Etype (New_E))) | |
4133 | then | |
4134 | return False; | |
4135 | end if; | |
4136 | end if; | |
4137 | ||
4138 | Next_Elmt (Prim_Elt); | |
4139 | end loop; | |
4140 | ||
4141 | -- If no match found, then the new subprogram does | |
4142 | -- not override in the generic (nor in the instance). | |
4143 | ||
4144 | return True; | |
4145 | end; | |
4146 | end if; | |
4147 | else | |
4148 | return False; | |
4149 | end if; | |
4150 | end Is_Non_Overriding_Operation; | |
4151 | ||
4152 | ------------------------------ | |
4153 | -- Make_Inequality_Operator -- | |
4154 | ------------------------------ | |
4155 | ||
4156 | -- S is the defining identifier of an equality operator. We build a | |
4157 | -- subprogram declaration with the right signature. This operation is | |
4158 | -- intrinsic, because it is always expanded as the negation of the | |
4159 | -- call to the equality function. | |
4160 | ||
4161 | procedure Make_Inequality_Operator (S : Entity_Id) is | |
4162 | Loc : constant Source_Ptr := Sloc (S); | |
4163 | Decl : Node_Id; | |
4164 | Formals : List_Id; | |
4165 | Op_Name : Entity_Id; | |
4166 | ||
4167 | A : Entity_Id; | |
4168 | B : Entity_Id; | |
4169 | ||
4170 | begin | |
4171 | -- Check that equality was properly defined. | |
4172 | ||
4173 | if No (Next_Formal (First_Formal (S))) then | |
4174 | return; | |
4175 | end if; | |
4176 | ||
4177 | A := Make_Defining_Identifier (Loc, Chars (First_Formal (S))); | |
4178 | B := Make_Defining_Identifier (Loc, | |
4179 | Chars (Next_Formal (First_Formal (S)))); | |
4180 | ||
4181 | Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne); | |
4182 | ||
4183 | Formals := New_List ( | |
4184 | Make_Parameter_Specification (Loc, | |
4185 | Defining_Identifier => A, | |
4186 | Parameter_Type => | |
4187 | New_Reference_To (Etype (First_Formal (S)), Loc)), | |
4188 | ||
4189 | Make_Parameter_Specification (Loc, | |
4190 | Defining_Identifier => B, | |
4191 | Parameter_Type => | |
4192 | New_Reference_To (Etype (Next_Formal (First_Formal (S))), Loc))); | |
4193 | ||
4194 | Decl := | |
4195 | Make_Subprogram_Declaration (Loc, | |
4196 | Specification => | |
4197 | Make_Function_Specification (Loc, | |
4198 | Defining_Unit_Name => Op_Name, | |
4199 | Parameter_Specifications => Formals, | |
4200 | Subtype_Mark => New_Reference_To (Standard_Boolean, Loc))); | |
4201 | ||
4202 | -- Insert inequality right after equality if it is explicit or after | |
4203 | -- the derived type when implicit. These entities are created only | |
4204 | -- for visibility purposes, and eventually replaced in the course of | |
4205 | -- expansion, so they do not need to be attached to the tree and seen | |
4206 | -- by the back-end. Keeping them internal also avoids spurious freezing | |
4207 | -- problems. The parent field is set simply to make analysis safe. | |
4208 | ||
4209 | if No (Alias (S)) then | |
4210 | Set_Parent (Decl, Parent (Unit_Declaration_Node (S))); | |
4211 | else | |
4212 | Set_Parent (Decl, Parent (Parent (Etype (First_Formal (S))))); | |
4213 | end if; | |
4214 | ||
4215 | Mark_Rewrite_Insertion (Decl); | |
4216 | Set_Is_Intrinsic_Subprogram (Op_Name); | |
4217 | Analyze (Decl); | |
4218 | Set_Has_Completion (Op_Name); | |
4219 | Set_Corresponding_Equality (Op_Name, S); | |
4220 | Set_Is_Abstract (Op_Name, Is_Abstract (S)); | |
4221 | ||
4222 | end Make_Inequality_Operator; | |
4223 | ||
4224 | ---------------------- | |
4225 | -- May_Need_Actuals -- | |
4226 | ---------------------- | |
4227 | ||
4228 | procedure May_Need_Actuals (Fun : Entity_Id) is | |
4229 | F : Entity_Id; | |
4230 | B : Boolean; | |
4231 | ||
4232 | begin | |
4233 | F := First_Formal (Fun); | |
4234 | B := True; | |
4235 | ||
4236 | while Present (F) loop | |
4237 | if No (Default_Value (F)) then | |
4238 | B := False; | |
4239 | exit; | |
4240 | end if; | |
4241 | ||
4242 | Next_Formal (F); | |
4243 | end loop; | |
4244 | ||
4245 | Set_Needs_No_Actuals (Fun, B); | |
4246 | end May_Need_Actuals; | |
4247 | ||
4248 | --------------------- | |
4249 | -- Mode_Conformant -- | |
4250 | --------------------- | |
4251 | ||
4252 | function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is | |
4253 | Result : Boolean; | |
4254 | ||
4255 | begin | |
4256 | Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result); | |
4257 | return Result; | |
4258 | end Mode_Conformant; | |
4259 | ||
4260 | --------------------------- | |
4261 | -- New_Overloaded_Entity -- | |
4262 | --------------------------- | |
4263 | ||
4264 | procedure New_Overloaded_Entity | |
4265 | (S : Entity_Id; | |
4266 | Derived_Type : Entity_Id := Empty) | |
4267 | is | |
fbf5a39b AC |
4268 | E : Entity_Id; |
4269 | -- Entity that S overrides | |
4270 | ||
996ae0b0 | 4271 | Prev_Vis : Entity_Id := Empty; |
fbf5a39b | 4272 | -- Needs comment ??? |
996ae0b0 RK |
4273 | |
4274 | function Is_Private_Declaration (E : Entity_Id) return Boolean; | |
4275 | -- Check that E is declared in the private part of the current package, | |
4276 | -- or in the package body, where it may hide a previous declaration. | |
fbf5a39b | 4277 | -- We can't use In_Private_Part by itself because this flag is also |
996ae0b0 RK |
4278 | -- set when freezing entities, so we must examine the place of the |
4279 | -- declaration in the tree, and recognize wrapper packages as well. | |
4280 | ||
4281 | procedure Maybe_Primitive_Operation (Overriding : Boolean := False); | |
4282 | -- If the subprogram being analyzed is a primitive operation of | |
4283 | -- the type of one of its formals, set the corresponding flag. | |
4284 | ||
4285 | ---------------------------- | |
4286 | -- Is_Private_Declaration -- | |
4287 | ---------------------------- | |
4288 | ||
4289 | function Is_Private_Declaration (E : Entity_Id) return Boolean is | |
4290 | Priv_Decls : List_Id; | |
4291 | Decl : constant Node_Id := Unit_Declaration_Node (E); | |
4292 | ||
4293 | begin | |
4294 | if Is_Package (Current_Scope) | |
4295 | and then In_Private_Part (Current_Scope) | |
4296 | then | |
4297 | Priv_Decls := | |
4298 | Private_Declarations ( | |
4299 | Specification (Unit_Declaration_Node (Current_Scope))); | |
4300 | ||
4301 | return In_Package_Body (Current_Scope) | |
4302 | or else List_Containing (Decl) = Priv_Decls | |
4303 | or else (Nkind (Parent (Decl)) = N_Package_Specification | |
4304 | and then not Is_Compilation_Unit ( | |
4305 | Defining_Entity (Parent (Decl))) | |
4306 | and then List_Containing (Parent (Parent (Decl))) | |
4307 | = Priv_Decls); | |
4308 | else | |
4309 | return False; | |
4310 | end if; | |
4311 | end Is_Private_Declaration; | |
4312 | ||
4313 | ------------------------------- | |
4314 | -- Maybe_Primitive_Operation -- | |
4315 | ------------------------------- | |
4316 | ||
4317 | procedure Maybe_Primitive_Operation (Overriding : Boolean := False) is | |
4318 | Formal : Entity_Id; | |
4319 | F_Typ : Entity_Id; | |
07fc65c4 | 4320 | B_Typ : Entity_Id; |
996ae0b0 RK |
4321 | |
4322 | function Visible_Part_Type (T : Entity_Id) return Boolean; | |
4323 | -- Returns true if T is declared in the visible part of | |
4324 | -- the current package scope; otherwise returns false. | |
4325 | -- Assumes that T is declared in a package. | |
4326 | ||
4327 | procedure Check_Private_Overriding (T : Entity_Id); | |
4328 | -- Checks that if a primitive abstract subprogram of a visible | |
4329 | -- abstract type is declared in a private part, then it must | |
4330 | -- override an abstract subprogram declared in the visible part. | |
4331 | -- Also checks that if a primitive function with a controlling | |
4332 | -- result is declared in a private part, then it must override | |
4333 | -- a function declared in the visible part. | |
4334 | ||
4335 | ------------------------------ | |
4336 | -- Check_Private_Overriding -- | |
4337 | ------------------------------ | |
4338 | ||
4339 | procedure Check_Private_Overriding (T : Entity_Id) is | |
4340 | begin | |
4341 | if Ekind (Current_Scope) = E_Package | |
4342 | and then In_Private_Part (Current_Scope) | |
4343 | and then Visible_Part_Type (T) | |
4344 | and then not In_Instance | |
4345 | then | |
4346 | if Is_Abstract (T) | |
4347 | and then Is_Abstract (S) | |
4348 | and then (not Overriding or else not Is_Abstract (E)) | |
4349 | then | |
4350 | Error_Msg_N ("abstract subprograms must be visible " | |
4351 | & "('R'M 3.9.3(10))!", S); | |
4352 | ||
4353 | elsif Ekind (S) = E_Function | |
4354 | and then Is_Tagged_Type (T) | |
4355 | and then T = Base_Type (Etype (S)) | |
4356 | and then not Overriding | |
4357 | then | |
4358 | Error_Msg_N | |
4359 | ("private function with tagged result must" | |
4360 | & " override visible-part function", S); | |
4361 | Error_Msg_N | |
4362 | ("\move subprogram to the visible part" | |
4363 | & " ('R'M 3.9.3(10))", S); | |
4364 | end if; | |
4365 | end if; | |
4366 | end Check_Private_Overriding; | |
4367 | ||
4368 | ----------------------- | |
4369 | -- Visible_Part_Type -- | |
4370 | ----------------------- | |
4371 | ||
4372 | function Visible_Part_Type (T : Entity_Id) return Boolean is | |
07fc65c4 GB |
4373 | P : constant Node_Id := Unit_Declaration_Node (Scope (T)); |
4374 | N : Node_Id; | |
996ae0b0 RK |
4375 | |
4376 | begin | |
4377 | -- If the entity is a private type, then it must be | |
4378 | -- declared in a visible part. | |
4379 | ||
4380 | if Ekind (T) in Private_Kind then | |
4381 | return True; | |
4382 | end if; | |
4383 | ||
4384 | -- Otherwise, we traverse the visible part looking for its | |
4385 | -- corresponding declaration. We cannot use the declaration | |
4386 | -- node directly because in the private part the entity of a | |
4387 | -- private type is the one in the full view, which does not | |
4388 | -- indicate that it is the completion of something visible. | |
4389 | ||
07fc65c4 | 4390 | N := First (Visible_Declarations (Specification (P))); |
996ae0b0 RK |
4391 | while Present (N) loop |
4392 | if Nkind (N) = N_Full_Type_Declaration | |
4393 | and then Present (Defining_Identifier (N)) | |
4394 | and then T = Defining_Identifier (N) | |
4395 | then | |
4396 | return True; | |
4397 | ||
4398 | elsif (Nkind (N) = N_Private_Type_Declaration | |
4399 | or else | |
4400 | Nkind (N) = N_Private_Extension_Declaration) | |
4401 | and then Present (Defining_Identifier (N)) | |
4402 | and then T = Full_View (Defining_Identifier (N)) | |
4403 | then | |
4404 | return True; | |
4405 | end if; | |
4406 | ||
4407 | Next (N); | |
4408 | end loop; | |
4409 | ||
4410 | return False; | |
4411 | end Visible_Part_Type; | |
4412 | ||
4413 | -- Start of processing for Maybe_Primitive_Operation | |
4414 | ||
4415 | begin | |
4416 | if not Comes_From_Source (S) then | |
4417 | null; | |
4418 | ||
4419 | elsif (Ekind (Current_Scope) = E_Package | |
4420 | and then not In_Package_Body (Current_Scope)) | |
4421 | or else Overriding | |
4422 | then | |
07fc65c4 | 4423 | -- For function, check return type |
996ae0b0 | 4424 | |
07fc65c4 GB |
4425 | if Ekind (S) = E_Function then |
4426 | B_Typ := Base_Type (Etype (S)); | |
4427 | ||
4428 | if Scope (B_Typ) = Current_Scope then | |
4429 | Set_Has_Primitive_Operations (B_Typ); | |
4430 | Check_Private_Overriding (B_Typ); | |
4431 | end if; | |
996ae0b0 RK |
4432 | end if; |
4433 | ||
07fc65c4 | 4434 | -- For all subprograms, check formals |
996ae0b0 | 4435 | |
07fc65c4 | 4436 | Formal := First_Formal (S); |
996ae0b0 RK |
4437 | while Present (Formal) loop |
4438 | if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then | |
4439 | F_Typ := Designated_Type (Etype (Formal)); | |
4440 | else | |
4441 | F_Typ := Etype (Formal); | |
4442 | end if; | |
4443 | ||
07fc65c4 GB |
4444 | B_Typ := Base_Type (F_Typ); |
4445 | ||
4446 | if Scope (B_Typ) = Current_Scope then | |
4447 | Set_Has_Primitive_Operations (B_Typ); | |
4448 | Check_Private_Overriding (B_Typ); | |
996ae0b0 RK |
4449 | end if; |
4450 | ||
4451 | Next_Formal (Formal); | |
4452 | end loop; | |
996ae0b0 RK |
4453 | end if; |
4454 | end Maybe_Primitive_Operation; | |
4455 | ||
4456 | -- Start of processing for New_Overloaded_Entity | |
4457 | ||
4458 | begin | |
fbf5a39b AC |
4459 | -- We need to look for an entity that S may override. This must be a |
4460 | -- homonym in the current scope, so we look for the first homonym of | |
4461 | -- S in the current scope as the starting point for the search. | |
4462 | ||
4463 | E := Current_Entity_In_Scope (S); | |
4464 | ||
4465 | -- If there is no homonym then this is definitely not overriding | |
4466 | ||
996ae0b0 RK |
4467 | if No (E) then |
4468 | Enter_Overloaded_Entity (S); | |
4469 | Check_Dispatching_Operation (S, Empty); | |
4470 | Maybe_Primitive_Operation; | |
4471 | ||
fbf5a39b AC |
4472 | -- If there is a homonym that is not overloadable, then we have an |
4473 | -- error, except for the special cases checked explicitly below. | |
4474 | ||
996ae0b0 RK |
4475 | elsif not Is_Overloadable (E) then |
4476 | ||
4477 | -- Check for spurious conflict produced by a subprogram that has the | |
4478 | -- same name as that of the enclosing generic package. The conflict | |
4479 | -- occurs within an instance, between the subprogram and the renaming | |
4480 | -- declaration for the package. After the subprogram, the package | |
4481 | -- renaming declaration becomes hidden. | |
4482 | ||
4483 | if Ekind (E) = E_Package | |
4484 | and then Present (Renamed_Object (E)) | |
4485 | and then Renamed_Object (E) = Current_Scope | |
4486 | and then Nkind (Parent (Renamed_Object (E))) = | |
4487 | N_Package_Specification | |
4488 | and then Present (Generic_Parent (Parent (Renamed_Object (E)))) | |
4489 | then | |
4490 | Set_Is_Hidden (E); | |
4491 | Set_Is_Immediately_Visible (E, False); | |
4492 | Enter_Overloaded_Entity (S); | |
4493 | Set_Homonym (S, Homonym (E)); | |
4494 | Check_Dispatching_Operation (S, Empty); | |
4495 | ||
4496 | -- If the subprogram is implicit it is hidden by the previous | |
4497 | -- declaration. However if it is dispatching, it must appear in | |
4498 | -- the dispatch table anyway, because it can be dispatched to | |
4499 | -- even if it cannot be called directly. | |
4500 | ||
4501 | elsif Present (Alias (S)) | |
4502 | and then not Comes_From_Source (S) | |
4503 | then | |
4504 | Set_Scope (S, Current_Scope); | |
4505 | ||
4506 | if Is_Dispatching_Operation (Alias (S)) then | |
4507 | Check_Dispatching_Operation (S, Empty); | |
4508 | end if; | |
4509 | ||
4510 | return; | |
4511 | ||
4512 | else | |
4513 | Error_Msg_Sloc := Sloc (E); | |
4514 | Error_Msg_N ("& conflicts with declaration#", S); | |
4515 | ||
fbf5a39b | 4516 | -- Useful additional warning |
996ae0b0 RK |
4517 | |
4518 | if Is_Generic_Unit (E) then | |
4519 | Error_Msg_N ("\previous generic unit cannot be overloaded", S); | |
4520 | end if; | |
4521 | ||
4522 | return; | |
4523 | end if; | |
4524 | ||
fbf5a39b AC |
4525 | -- E exists and is overloadable |
4526 | ||
996ae0b0 | 4527 | else |
fbf5a39b AC |
4528 | -- Loop through E and its homonyms to determine if any of them |
4529 | -- is the candidate for overriding by S. | |
996ae0b0 RK |
4530 | |
4531 | while Present (E) loop | |
fbf5a39b AC |
4532 | |
4533 | -- Definitely not interesting if not in the current scope | |
4534 | ||
996ae0b0 RK |
4535 | if Scope (E) /= Current_Scope then |
4536 | null; | |
4537 | ||
fbf5a39b AC |
4538 | -- Check if we have type conformance |
4539 | ||
996ae0b0 RK |
4540 | elsif Type_Conformant (E, S) then |
4541 | ||
4542 | -- If the old and new entities have the same profile and | |
4543 | -- one is not the body of the other, then this is an error, | |
4544 | -- unless one of them is implicitly declared. | |
4545 | ||
4546 | -- There are some cases when both can be implicit, for example | |
4547 | -- when both a literal and a function that overrides it are | |
4548 | -- inherited in a derivation, or when an inhertited operation | |
4549 | -- of a tagged full type overrides the ineherited operation of | |
4550 | -- a private extension. Ada 83 had a special rule for the | |
4551 | -- the literal case. In Ada95, the later implicit operation | |
4552 | -- hides the former, and the literal is always the former. | |
4553 | -- In the odd case where both are derived operations declared | |
4554 | -- at the same point, both operations should be declared, | |
4555 | -- and in that case we bypass the following test and proceed | |
4556 | -- to the next part (this can only occur for certain obscure | |
4557 | -- cases involving homographs in instances and can't occur for | |
4558 | -- dispatching operations ???). Note that the following | |
4559 | -- condition is less than clear. For example, it's not at | |
4560 | -- all clear why there's a test for E_Entry here. ??? | |
4561 | ||
4562 | if Present (Alias (S)) | |
4563 | and then (No (Alias (E)) | |
4564 | or else Comes_From_Source (E) | |
4565 | or else Is_Dispatching_Operation (E)) | |
4566 | and then | |
4567 | (Ekind (E) = E_Entry | |
4568 | or else Ekind (E) /= E_Enumeration_Literal) | |
4569 | then | |
4570 | -- When an derived operation is overloaded it may be due | |
4571 | -- to the fact that the full view of a private extension | |
4572 | -- re-inherits. It has to be dealt with. | |
4573 | ||
4574 | if Is_Package (Current_Scope) | |
4575 | and then In_Private_Part (Current_Scope) | |
4576 | then | |
4577 | Check_Operation_From_Private_View (S, E); | |
4578 | end if; | |
4579 | ||
4580 | -- In any case the implicit operation remains hidden by | |
4581 | -- the existing declaration. | |
4582 | ||
4583 | return; | |
4584 | ||
4585 | -- Within an instance, the renaming declarations for | |
4586 | -- actual subprograms may become ambiguous, but they do | |
4587 | -- not hide each other. | |
4588 | ||
4589 | elsif Ekind (E) /= E_Entry | |
4590 | and then not Comes_From_Source (E) | |
4591 | and then not Is_Generic_Instance (E) | |
4592 | and then (Present (Alias (E)) | |
4593 | or else Is_Intrinsic_Subprogram (E)) | |
4594 | and then (not In_Instance | |
4595 | or else No (Parent (E)) | |
4596 | or else Nkind (Unit_Declaration_Node (E)) /= | |
4597 | N_Subprogram_Renaming_Declaration) | |
4598 | then | |
4599 | -- A subprogram child unit is not allowed to override | |
4600 | -- an inherited subprogram (10.1.1(20)). | |
4601 | ||
4602 | if Is_Child_Unit (S) then | |
4603 | Error_Msg_N | |
4604 | ("child unit overrides inherited subprogram in parent", | |
4605 | S); | |
4606 | return; | |
4607 | end if; | |
4608 | ||
4609 | if Is_Non_Overriding_Operation (E, S) then | |
4610 | Enter_Overloaded_Entity (S); | |
4611 | if not Present (Derived_Type) | |
4612 | or else Is_Tagged_Type (Derived_Type) | |
4613 | then | |
4614 | Check_Dispatching_Operation (S, Empty); | |
4615 | end if; | |
4616 | ||
4617 | return; | |
4618 | end if; | |
4619 | ||
4620 | -- E is a derived operation or an internal operator which | |
4621 | -- is being overridden. Remove E from further visibility. | |
4622 | -- Furthermore, if E is a dispatching operation, it must be | |
4623 | -- replaced in the list of primitive operations of its type | |
4624 | -- (see Override_Dispatching_Operation). | |
4625 | ||
4626 | declare | |
4627 | Prev : Entity_Id; | |
4628 | ||
4629 | begin | |
4630 | Prev := First_Entity (Current_Scope); | |
4631 | ||
4632 | while Present (Prev) | |
4633 | and then Next_Entity (Prev) /= E | |
4634 | loop | |
4635 | Next_Entity (Prev); | |
4636 | end loop; | |
4637 | ||
4638 | -- It is possible for E to be in the current scope and | |
4639 | -- yet not in the entity chain. This can only occur in a | |
4640 | -- generic context where E is an implicit concatenation | |
4641 | -- in the formal part, because in a generic body the | |
4642 | -- entity chain starts with the formals. | |
4643 | ||
4644 | pragma Assert | |
4645 | (Present (Prev) or else Chars (E) = Name_Op_Concat); | |
4646 | ||
4647 | -- E must be removed both from the entity_list of the | |
4648 | -- current scope, and from the visibility chain | |
4649 | ||
4650 | if Debug_Flag_E then | |
4651 | Write_Str ("Override implicit operation "); | |
4652 | Write_Int (Int (E)); | |
4653 | Write_Eol; | |
4654 | end if; | |
4655 | ||
4656 | -- If E is a predefined concatenation, it stands for four | |
4657 | -- different operations. As a result, a single explicit | |
4658 | -- declaration does not hide it. In a possible ambiguous | |
4659 | -- situation, Disambiguate chooses the user-defined op, | |
4660 | -- so it is correct to retain the previous internal one. | |
4661 | ||
4662 | if Chars (E) /= Name_Op_Concat | |
4663 | or else Ekind (E) /= E_Operator | |
4664 | then | |
4665 | -- For nondispatching derived operations that are | |
4666 | -- overridden by a subprogram declared in the private | |
4667 | -- part of a package, we retain the derived subprogram | |
4668 | -- but mark it as not immediately visible. If the | |
4669 | -- derived operation was declared in the visible part | |
4670 | -- then this ensures that it will still be visible | |
4671 | -- outside the package with the proper signature | |
4672 | -- (calls from outside must also be directed to this | |
4673 | -- version rather than the overriding one, unlike the | |
4674 | -- dispatching case). Calls from inside the package | |
4675 | -- will still resolve to the overriding subprogram | |
4676 | -- since the derived one is marked as not visible | |
4677 | -- within the package. | |
4678 | ||
4679 | -- If the private operation is dispatching, we achieve | |
4680 | -- the overriding by keeping the implicit operation | |
4681 | -- but setting its alias to be the overring one. In | |
4682 | -- this fashion the proper body is executed in all | |
4683 | -- cases, but the original signature is used outside | |
4684 | -- of the package. | |
4685 | ||
4686 | -- If the overriding is not in the private part, we | |
4687 | -- remove the implicit operation altogether. | |
4688 | ||
4689 | if Is_Private_Declaration (S) then | |
4690 | ||
4691 | if not Is_Dispatching_Operation (E) then | |
4692 | Set_Is_Immediately_Visible (E, False); | |
4693 | else | |
4694 | ||
4695 | -- work done in Override_Dispatching_Operation. | |
4696 | ||
4697 | null; | |
4698 | end if; | |
996ae0b0 | 4699 | |
fbf5a39b AC |
4700 | else |
4701 | -- Find predecessor of E in Homonym chain | |
996ae0b0 RK |
4702 | |
4703 | if E = Current_Entity (E) then | |
4704 | Prev_Vis := Empty; | |
4705 | else | |
4706 | Prev_Vis := Current_Entity (E); | |
4707 | while Homonym (Prev_Vis) /= E loop | |
4708 | Prev_Vis := Homonym (Prev_Vis); | |
4709 | end loop; | |
4710 | end if; | |
4711 | ||
4712 | if Prev_Vis /= Empty then | |
4713 | ||
4714 | -- Skip E in the visibility chain | |
4715 | ||
4716 | Set_Homonym (Prev_Vis, Homonym (E)); | |
4717 | ||
4718 | else | |
4719 | Set_Name_Entity_Id (Chars (E), Homonym (E)); | |
4720 | end if; | |
4721 | ||
4722 | Set_Next_Entity (Prev, Next_Entity (E)); | |
4723 | ||
4724 | if No (Next_Entity (Prev)) then | |
4725 | Set_Last_Entity (Current_Scope, Prev); | |
4726 | end if; | |
4727 | ||
4728 | end if; | |
4729 | end if; | |
4730 | ||
4731 | Enter_Overloaded_Entity (S); | |
fbf5a39b | 4732 | Set_Is_Overriding_Operation (S); |
996ae0b0 RK |
4733 | |
4734 | if Is_Dispatching_Operation (E) then | |
fbf5a39b | 4735 | |
996ae0b0 RK |
4736 | -- An overriding dispatching subprogram inherits |
4737 | -- the convention of the overridden subprogram | |
4738 | -- (by AI-117). | |
4739 | ||
4740 | Set_Convention (S, Convention (E)); | |
4741 | ||
4742 | Check_Dispatching_Operation (S, E); | |
4743 | else | |
4744 | Check_Dispatching_Operation (S, Empty); | |
4745 | end if; | |
4746 | ||
4747 | Maybe_Primitive_Operation (Overriding => True); | |
4748 | goto Check_Inequality; | |
4749 | end; | |
4750 | ||
4751 | -- Apparent redeclarations in instances can occur when two | |
4752 | -- formal types get the same actual type. The subprograms in | |
4753 | -- in the instance are legal, even if not callable from the | |
4754 | -- outside. Calls from within are disambiguated elsewhere. | |
4755 | -- For dispatching operations in the visible part, the usual | |
4756 | -- rules apply, and operations with the same profile are not | |
4757 | -- legal (B830001). | |
4758 | ||
4759 | elsif (In_Instance_Visible_Part | |
4760 | and then not Is_Dispatching_Operation (E)) | |
4761 | or else In_Instance_Not_Visible | |
4762 | then | |
4763 | null; | |
4764 | ||
4765 | -- Here we have a real error (identical profile) | |
4766 | ||
4767 | else | |
4768 | Error_Msg_Sloc := Sloc (E); | |
4769 | ||
4770 | -- Avoid cascaded errors if the entity appears in | |
4771 | -- subsequent calls. | |
4772 | ||
4773 | Set_Scope (S, Current_Scope); | |
4774 | ||
4775 | Error_Msg_N ("& conflicts with declaration#", S); | |
4776 | ||
4777 | if Is_Generic_Instance (S) | |
4778 | and then not Has_Completion (E) | |
4779 | then | |
4780 | Error_Msg_N | |
4781 | ("\instantiation cannot provide body for it", S); | |
4782 | end if; | |
4783 | ||
4784 | return; | |
4785 | end if; | |
4786 | ||
4787 | else | |
4788 | null; | |
4789 | end if; | |
4790 | ||
4791 | Prev_Vis := E; | |
4792 | E := Homonym (E); | |
4793 | end loop; | |
4794 | ||
4795 | -- On exit, we know that S is a new entity | |
4796 | ||
4797 | Enter_Overloaded_Entity (S); | |
4798 | Maybe_Primitive_Operation; | |
4799 | ||
4800 | -- If S is a derived operation for an untagged type then | |
4801 | -- by definition it's not a dispatching operation (even | |
4802 | -- if the parent operation was dispatching), so we don't | |
4803 | -- call Check_Dispatching_Operation in that case. | |
4804 | ||
4805 | if not Present (Derived_Type) | |
4806 | or else Is_Tagged_Type (Derived_Type) | |
4807 | then | |
4808 | Check_Dispatching_Operation (S, Empty); | |
4809 | end if; | |
4810 | end if; | |
4811 | ||
4812 | -- If this is a user-defined equality operator that is not | |
4813 | -- a derived subprogram, create the corresponding inequality. | |
4814 | -- If the operation is dispatching, the expansion is done | |
fbf5a39b | 4815 | -- elsewhere, and we do not create an explicit inequality |
996ae0b0 RK |
4816 | -- operation. |
4817 | ||
4818 | <<Check_Inequality>> | |
4819 | if Chars (S) = Name_Op_Eq | |
4820 | and then Etype (S) = Standard_Boolean | |
4821 | and then Present (Parent (S)) | |
4822 | and then not Is_Dispatching_Operation (S) | |
4823 | then | |
4824 | Make_Inequality_Operator (S); | |
4825 | end if; | |
996ae0b0 RK |
4826 | end New_Overloaded_Entity; |
4827 | ||
4828 | --------------------- | |
4829 | -- Process_Formals -- | |
4830 | --------------------- | |
4831 | ||
4832 | procedure Process_Formals | |
07fc65c4 | 4833 | (T : List_Id; |
996ae0b0 RK |
4834 | Related_Nod : Node_Id) |
4835 | is | |
4836 | Param_Spec : Node_Id; | |
4837 | Formal : Entity_Id; | |
4838 | Formal_Type : Entity_Id; | |
4839 | Default : Node_Id; | |
4840 | Ptype : Entity_Id; | |
4841 | ||
07fc65c4 GB |
4842 | function Is_Class_Wide_Default (D : Node_Id) return Boolean; |
4843 | -- Check whether the default has a class-wide type. After analysis | |
4844 | -- the default has the type of the formal, so we must also check | |
4845 | -- explicitly for an access attribute. | |
4846 | ||
4847 | --------------------------- | |
4848 | -- Is_Class_Wide_Default -- | |
4849 | --------------------------- | |
4850 | ||
4851 | function Is_Class_Wide_Default (D : Node_Id) return Boolean is | |
4852 | begin | |
4853 | return Is_Class_Wide_Type (Designated_Type (Etype (D))) | |
4854 | or else (Nkind (D) = N_Attribute_Reference | |
4855 | and then Attribute_Name (D) = Name_Access | |
4856 | and then Is_Class_Wide_Type (Etype (Prefix (D)))); | |
4857 | end Is_Class_Wide_Default; | |
4858 | ||
4859 | -- Start of processing for Process_Formals | |
4860 | ||
996ae0b0 RK |
4861 | begin |
4862 | -- In order to prevent premature use of the formals in the same formal | |
4863 | -- part, the Ekind is left undefined until all default expressions are | |
4864 | -- analyzed. The Ekind is established in a separate loop at the end. | |
4865 | ||
4866 | Param_Spec := First (T); | |
4867 | ||
4868 | while Present (Param_Spec) loop | |
4869 | ||
4870 | Formal := Defining_Identifier (Param_Spec); | |
4871 | Enter_Name (Formal); | |
4872 | ||
4873 | -- Case of ordinary parameters | |
4874 | ||
4875 | if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then | |
4876 | Find_Type (Parameter_Type (Param_Spec)); | |
4877 | Ptype := Parameter_Type (Param_Spec); | |
4878 | ||
4879 | if Ptype = Error then | |
4880 | goto Continue; | |
4881 | end if; | |
4882 | ||
4883 | Formal_Type := Entity (Ptype); | |
4884 | ||
4885 | if Ekind (Formal_Type) = E_Incomplete_Type | |
4886 | or else (Is_Class_Wide_Type (Formal_Type) | |
4887 | and then Ekind (Root_Type (Formal_Type)) = | |
4888 | E_Incomplete_Type) | |
4889 | then | |
fbf5a39b AC |
4890 | |
4891 | -- Incomplete tagged types that are made visible through | |
4892 | -- a limited with_clause are valid formal types. | |
4893 | ||
4894 | if From_With_Type (Formal_Type) | |
4895 | and then Is_Tagged_Type (Formal_Type) | |
4896 | then | |
4897 | null; | |
4898 | ||
4899 | elsif Nkind (Parent (T)) /= N_Access_Function_Definition | |
996ae0b0 RK |
4900 | and then Nkind (Parent (T)) /= N_Access_Procedure_Definition |
4901 | then | |
4902 | Error_Msg_N ("invalid use of incomplete type", Param_Spec); | |
4903 | end if; | |
4904 | ||
4905 | elsif Ekind (Formal_Type) = E_Void then | |
4906 | Error_Msg_NE ("premature use of&", | |
4907 | Parameter_Type (Param_Spec), Formal_Type); | |
4908 | end if; | |
4909 | ||
4910 | -- An access formal type | |
4911 | ||
4912 | else | |
4913 | Formal_Type := | |
4914 | Access_Definition (Related_Nod, Parameter_Type (Param_Spec)); | |
4915 | end if; | |
4916 | ||
4917 | Set_Etype (Formal, Formal_Type); | |
4918 | ||
fbf5a39b | 4919 | Default := Expression (Param_Spec); |
996ae0b0 RK |
4920 | |
4921 | if Present (Default) then | |
4922 | if Out_Present (Param_Spec) then | |
4923 | Error_Msg_N | |
4924 | ("default initialization only allowed for IN parameters", | |
4925 | Param_Spec); | |
4926 | end if; | |
4927 | ||
4928 | -- Do the special preanalysis of the expression (see section on | |
4929 | -- "Handling of Default Expressions" in the spec of package Sem). | |
4930 | ||
fbf5a39b | 4931 | Analyze_Per_Use_Expression (Default, Formal_Type); |
996ae0b0 RK |
4932 | |
4933 | -- Check that the designated type of an access parameter's | |
4934 | -- default is not a class-wide type unless the parameter's | |
4935 | -- designated type is also class-wide. | |
4936 | ||
4937 | if Ekind (Formal_Type) = E_Anonymous_Access_Type | |
07fc65c4 | 4938 | and then Is_Class_Wide_Default (Default) |
996ae0b0 RK |
4939 | and then not Is_Class_Wide_Type (Designated_Type (Formal_Type)) |
4940 | then | |
07fc65c4 GB |
4941 | Error_Msg_N |
4942 | ("access to class-wide expression not allowed here", Default); | |
996ae0b0 RK |
4943 | end if; |
4944 | end if; | |
4945 | ||
4946 | <<Continue>> | |
4947 | Next (Param_Spec); | |
4948 | end loop; | |
4949 | ||
4950 | -- Now set the kind (mode) of each formal | |
4951 | ||
4952 | Param_Spec := First (T); | |
4953 | ||
4954 | while Present (Param_Spec) loop | |
4955 | Formal := Defining_Identifier (Param_Spec); | |
4956 | Set_Formal_Mode (Formal); | |
4957 | ||
4958 | if Ekind (Formal) = E_In_Parameter then | |
4959 | Set_Default_Value (Formal, Expression (Param_Spec)); | |
4960 | ||
4961 | if Present (Expression (Param_Spec)) then | |
4962 | Default := Expression (Param_Spec); | |
4963 | ||
4964 | if Is_Scalar_Type (Etype (Default)) then | |
4965 | if Nkind | |
4966 | (Parameter_Type (Param_Spec)) /= N_Access_Definition | |
4967 | then | |
4968 | Formal_Type := Entity (Parameter_Type (Param_Spec)); | |
4969 | ||
4970 | else | |
4971 | Formal_Type := Access_Definition | |
4972 | (Related_Nod, Parameter_Type (Param_Spec)); | |
4973 | end if; | |
4974 | ||
4975 | Apply_Scalar_Range_Check (Default, Formal_Type); | |
4976 | end if; | |
4977 | ||
4978 | end if; | |
4979 | end if; | |
4980 | ||
4981 | Next (Param_Spec); | |
4982 | end loop; | |
4983 | ||
4984 | end Process_Formals; | |
4985 | ||
fbf5a39b AC |
4986 | ---------------------------- |
4987 | -- Reference_Body_Formals -- | |
4988 | ---------------------------- | |
4989 | ||
4990 | procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is | |
4991 | Fs : Entity_Id; | |
4992 | Fb : Entity_Id; | |
4993 | ||
4994 | begin | |
4995 | if Error_Posted (Spec) then | |
4996 | return; | |
4997 | end if; | |
4998 | ||
4999 | Fs := First_Formal (Spec); | |
5000 | Fb := First_Formal (Bod); | |
5001 | ||
5002 | while Present (Fs) loop | |
5003 | Generate_Reference (Fs, Fb, 'b'); | |
5004 | ||
5005 | if Style_Check then | |
5006 | Style.Check_Identifier (Fb, Fs); | |
5007 | end if; | |
5008 | ||
5009 | Set_Spec_Entity (Fb, Fs); | |
5010 | Set_Referenced (Fs, False); | |
5011 | Next_Formal (Fs); | |
5012 | Next_Formal (Fb); | |
5013 | end loop; | |
5014 | end Reference_Body_Formals; | |
5015 | ||
996ae0b0 RK |
5016 | ------------------------- |
5017 | -- Set_Actual_Subtypes -- | |
5018 | ------------------------- | |
5019 | ||
5020 | procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is | |
5021 | Loc : constant Source_Ptr := Sloc (N); | |
5022 | Decl : Node_Id; | |
5023 | Formal : Entity_Id; | |
5024 | T : Entity_Id; | |
5025 | First_Stmt : Node_Id := Empty; | |
5026 | AS_Needed : Boolean; | |
5027 | ||
5028 | begin | |
fbf5a39b AC |
5029 | -- If this is an emtpy initialization procedure, no need to create |
5030 | -- actual subtypes (small optimization). | |
5031 | ||
5032 | if Ekind (Subp) = E_Procedure | |
5033 | and then Is_Null_Init_Proc (Subp) | |
5034 | then | |
5035 | return; | |
5036 | end if; | |
5037 | ||
996ae0b0 RK |
5038 | Formal := First_Formal (Subp); |
5039 | while Present (Formal) loop | |
5040 | T := Etype (Formal); | |
5041 | ||
5042 | -- We never need an actual subtype for a constrained formal. | |
5043 | ||
5044 | if Is_Constrained (T) then | |
5045 | AS_Needed := False; | |
5046 | ||
5047 | -- If we have unknown discriminants, then we do not need an | |
5048 | -- actual subtype, or more accurately we cannot figure it out! | |
5049 | -- Note that all class-wide types have unknown discriminants. | |
5050 | ||
5051 | elsif Has_Unknown_Discriminants (T) then | |
5052 | AS_Needed := False; | |
5053 | ||
5054 | -- At this stage we have an unconstrained type that may need | |
5055 | -- an actual subtype. For sure the actual subtype is needed | |
5056 | -- if we have an unconstrained array type. | |
5057 | ||
5058 | elsif Is_Array_Type (T) then | |
5059 | AS_Needed := True; | |
5060 | ||
5061 | -- The only other case which needs an actual subtype is an | |
5062 | -- unconstrained record type which is an IN parameter (we | |
5063 | -- cannot generate actual subtypes for the OUT or IN OUT case, | |
5064 | -- since an assignment can change the discriminant values. | |
5065 | -- However we exclude the case of initialization procedures, | |
5066 | -- since discriminants are handled very specially in this context, | |
5067 | -- see the section entitled "Handling of Discriminants" in Einfo. | |
5068 | -- We also exclude the case of Discrim_SO_Functions (functions | |
5069 | -- used in front end layout mode for size/offset values), since | |
5070 | -- in such functions only discriminants are referenced, and not | |
5071 | -- only are such subtypes not needed, but they cannot always | |
5072 | -- be generated, because of order of elaboration issues. | |
5073 | ||
5074 | elsif Is_Record_Type (T) | |
5075 | and then Ekind (Formal) = E_In_Parameter | |
5076 | and then Chars (Formal) /= Name_uInit | |
5077 | and then not Is_Discrim_SO_Function (Subp) | |
5078 | then | |
5079 | AS_Needed := True; | |
5080 | ||
5081 | -- All other cases do not need an actual subtype | |
5082 | ||
5083 | else | |
5084 | AS_Needed := False; | |
5085 | end if; | |
5086 | ||
5087 | -- Generate actual subtypes for unconstrained arrays and | |
5088 | -- unconstrained discriminated records. | |
5089 | ||
5090 | if AS_Needed then | |
996ae0b0 RK |
5091 | |
5092 | if Nkind (N) = N_Accept_Statement then | |
fbf5a39b AC |
5093 | |
5094 | -- If expansion is active, The formal is replaced by a local | |
5095 | -- variable that renames the corresponding entry of the | |
5096 | -- parameter block, and it is this local variable that may | |
5097 | -- require an actual subtype. | |
5098 | ||
5099 | if Expander_Active then | |
5100 | Decl := Build_Actual_Subtype (T, Renamed_Object (Formal)); | |
5101 | else | |
5102 | Decl := Build_Actual_Subtype (T, Formal); | |
5103 | end if; | |
5104 | ||
996ae0b0 RK |
5105 | if Present (Handled_Statement_Sequence (N)) then |
5106 | First_Stmt := | |
5107 | First (Statements (Handled_Statement_Sequence (N))); | |
5108 | Prepend (Decl, Statements (Handled_Statement_Sequence (N))); | |
5109 | Mark_Rewrite_Insertion (Decl); | |
5110 | else | |
5111 | -- If the accept statement has no body, there will be | |
5112 | -- no reference to the actuals, so no need to compute | |
5113 | -- actual subtypes. | |
5114 | ||
5115 | return; | |
5116 | end if; | |
5117 | ||
5118 | else | |
fbf5a39b | 5119 | Decl := Build_Actual_Subtype (T, Formal); |
996ae0b0 RK |
5120 | Prepend (Decl, Declarations (N)); |
5121 | Mark_Rewrite_Insertion (Decl); | |
5122 | end if; | |
5123 | ||
5124 | Analyze (Decl); | |
5125 | ||
5126 | -- We need to freeze manually the generated type when it is | |
5127 | -- inserted anywhere else than in a declarative part. | |
5128 | ||
5129 | if Present (First_Stmt) then | |
5130 | Insert_List_Before_And_Analyze (First_Stmt, | |
5131 | Freeze_Entity (Defining_Identifier (Decl), Loc)); | |
5132 | end if; | |
5133 | ||
fbf5a39b AC |
5134 | if Nkind (N) = N_Accept_Statement |
5135 | and then Expander_Active | |
5136 | then | |
5137 | Set_Actual_Subtype (Renamed_Object (Formal), | |
5138 | Defining_Identifier (Decl)); | |
5139 | else | |
5140 | Set_Actual_Subtype (Formal, Defining_Identifier (Decl)); | |
5141 | end if; | |
996ae0b0 RK |
5142 | end if; |
5143 | ||
5144 | Next_Formal (Formal); | |
5145 | end loop; | |
5146 | end Set_Actual_Subtypes; | |
5147 | ||
5148 | --------------------- | |
5149 | -- Set_Formal_Mode -- | |
5150 | --------------------- | |
5151 | ||
5152 | procedure Set_Formal_Mode (Formal_Id : Entity_Id) is | |
5153 | Spec : constant Node_Id := Parent (Formal_Id); | |
5154 | ||
5155 | begin | |
5156 | -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters | |
5157 | -- since we ensure that corresponding actuals are always valid at the | |
5158 | -- point of the call. | |
5159 | ||
5160 | if Out_Present (Spec) then | |
996ae0b0 RK |
5161 | if Ekind (Scope (Formal_Id)) = E_Function |
5162 | or else Ekind (Scope (Formal_Id)) = E_Generic_Function | |
5163 | then | |
5164 | Error_Msg_N ("functions can only have IN parameters", Spec); | |
5165 | Set_Ekind (Formal_Id, E_In_Parameter); | |
5166 | ||
5167 | elsif In_Present (Spec) then | |
5168 | Set_Ekind (Formal_Id, E_In_Out_Parameter); | |
5169 | ||
5170 | else | |
fbf5a39b AC |
5171 | Set_Ekind (Formal_Id, E_Out_Parameter); |
5172 | Set_Never_Set_In_Source (Formal_Id, True); | |
5173 | Set_Is_True_Constant (Formal_Id, False); | |
5174 | Set_Current_Value (Formal_Id, Empty); | |
996ae0b0 RK |
5175 | end if; |
5176 | ||
5177 | else | |
5178 | Set_Ekind (Formal_Id, E_In_Parameter); | |
5179 | end if; | |
5180 | ||
fbf5a39b AC |
5181 | -- Set Is_Known_Non_Null for access parameters since the language |
5182 | -- guarantees that access parameters are always non-null. We also | |
5183 | -- set Can_Never_Be_Null, since there is no way to change the value. | |
5184 | ||
5185 | if Nkind (Parameter_Type (Spec)) = N_Access_Definition then | |
5186 | Set_Is_Known_Non_Null (Formal_Id); | |
5187 | Set_Can_Never_Be_Null (Formal_Id); | |
5188 | end if; | |
5189 | ||
996ae0b0 RK |
5190 | Set_Mechanism (Formal_Id, Default_Mechanism); |
5191 | Set_Formal_Validity (Formal_Id); | |
5192 | end Set_Formal_Mode; | |
5193 | ||
5194 | ------------------------- | |
5195 | -- Set_Formal_Validity -- | |
5196 | ------------------------- | |
5197 | ||
5198 | procedure Set_Formal_Validity (Formal_Id : Entity_Id) is | |
5199 | begin | |
fbf5a39b AC |
5200 | -- If no validity checking, then we cannot assume anything about |
5201 | -- the validity of parameters, since we do not know there is any | |
5202 | -- checking of the validity on the call side. | |
996ae0b0 RK |
5203 | |
5204 | if not Validity_Checks_On then | |
5205 | return; | |
5206 | ||
fbf5a39b AC |
5207 | -- If validity checking for parameters is enabled, this means we are |
5208 | -- not supposed to make any assumptions about argument values. | |
5209 | ||
5210 | elsif Validity_Check_Parameters then | |
5211 | return; | |
5212 | ||
5213 | -- If we are checking in parameters, we will assume that the caller is | |
5214 | -- also checking parameters, so we can assume the parameter is valid. | |
5215 | ||
996ae0b0 RK |
5216 | elsif Ekind (Formal_Id) = E_In_Parameter |
5217 | and then Validity_Check_In_Params | |
5218 | then | |
5219 | Set_Is_Known_Valid (Formal_Id, True); | |
5220 | ||
fbf5a39b AC |
5221 | -- Similar treatment for IN OUT parameters |
5222 | ||
996ae0b0 RK |
5223 | elsif Ekind (Formal_Id) = E_In_Out_Parameter |
5224 | and then Validity_Check_In_Out_Params | |
5225 | then | |
5226 | Set_Is_Known_Valid (Formal_Id, True); | |
5227 | end if; | |
5228 | end Set_Formal_Validity; | |
5229 | ||
5230 | ------------------------ | |
5231 | -- Subtype_Conformant -- | |
5232 | ------------------------ | |
5233 | ||
5234 | function Subtype_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is | |
5235 | Result : Boolean; | |
5236 | ||
5237 | begin | |
5238 | Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result); | |
5239 | return Result; | |
5240 | end Subtype_Conformant; | |
5241 | ||
5242 | --------------------- | |
5243 | -- Type_Conformant -- | |
5244 | --------------------- | |
5245 | ||
5246 | function Type_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is | |
5247 | Result : Boolean; | |
5248 | ||
5249 | begin | |
5250 | Check_Conformance (New_Id, Old_Id, Type_Conformant, False, Result); | |
5251 | return Result; | |
5252 | end Type_Conformant; | |
5253 | ||
5254 | ------------------------------- | |
5255 | -- Valid_Operator_Definition -- | |
5256 | ------------------------------- | |
5257 | ||
5258 | procedure Valid_Operator_Definition (Designator : Entity_Id) is | |
5259 | N : Integer := 0; | |
5260 | F : Entity_Id; | |
5261 | Id : constant Name_Id := Chars (Designator); | |
5262 | N_OK : Boolean; | |
5263 | ||
5264 | begin | |
5265 | F := First_Formal (Designator); | |
5266 | ||
5267 | while Present (F) loop | |
5268 | N := N + 1; | |
5269 | ||
5270 | if Present (Default_Value (F)) then | |
5271 | Error_Msg_N | |
5272 | ("default values not allowed for operator parameters", | |
5273 | Parent (F)); | |
5274 | end if; | |
5275 | ||
5276 | Next_Formal (F); | |
5277 | end loop; | |
5278 | ||
5279 | -- Verify that user-defined operators have proper number of arguments | |
5280 | -- First case of operators which can only be unary | |
5281 | ||
5282 | if Id = Name_Op_Not | |
5283 | or else Id = Name_Op_Abs | |
5284 | then | |
5285 | N_OK := (N = 1); | |
5286 | ||
5287 | -- Case of operators which can be unary or binary | |
5288 | ||
5289 | elsif Id = Name_Op_Add | |
5290 | or Id = Name_Op_Subtract | |
5291 | then | |
5292 | N_OK := (N in 1 .. 2); | |
5293 | ||
5294 | -- All other operators can only be binary | |
5295 | ||
5296 | else | |
5297 | N_OK := (N = 2); | |
5298 | end if; | |
5299 | ||
5300 | if not N_OK then | |
5301 | Error_Msg_N | |
5302 | ("incorrect number of arguments for operator", Designator); | |
5303 | end if; | |
5304 | ||
5305 | if Id = Name_Op_Ne | |
5306 | and then Base_Type (Etype (Designator)) = Standard_Boolean | |
5307 | and then not Is_Intrinsic_Subprogram (Designator) | |
5308 | then | |
5309 | Error_Msg_N | |
5310 | ("explicit definition of inequality not allowed", Designator); | |
5311 | end if; | |
5312 | end Valid_Operator_Definition; | |
5313 | ||
5314 | end Sem_Ch6; |