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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S E M _ C H 6 --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
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 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Ch7; use Exp_Ch7;
35 with Exp_Tss; use Exp_Tss;
36 with Exp_Util; use Exp_Util;
37 with Fname; use Fname;
38 with Freeze; use Freeze;
39 with Itypes; use Itypes;
40 with Lib.Xref; use Lib.Xref;
41 with Layout; use Layout;
42 with Namet; use Namet;
43 with Lib; use Lib;
44 with Nlists; use Nlists;
45 with Nmake; use Nmake;
46 with Opt; use Opt;
47 with Output; use Output;
48 with Rtsfind; use Rtsfind;
49 with Sem; use Sem;
50 with Sem_Cat; use Sem_Cat;
51 with Sem_Ch3; use Sem_Ch3;
52 with Sem_Ch4; use Sem_Ch4;
53 with Sem_Ch5; use Sem_Ch5;
54 with Sem_Ch8; use Sem_Ch8;
55 with Sem_Ch10; use Sem_Ch10;
56 with Sem_Ch12; use Sem_Ch12;
57 with Sem_Disp; use Sem_Disp;
58 with Sem_Dist; use Sem_Dist;
59 with Sem_Elim; use Sem_Elim;
60 with Sem_Eval; use Sem_Eval;
61 with Sem_Mech; use Sem_Mech;
62 with Sem_Prag; use Sem_Prag;
63 with Sem_Res; use Sem_Res;
64 with Sem_Util; use Sem_Util;
65 with Sem_Type; use Sem_Type;
66 with Sem_Warn; use Sem_Warn;
67 with Sinput; use Sinput;
68 with Stand; use Stand;
69 with Sinfo; use Sinfo;
70 with Sinfo.CN; use Sinfo.CN;
71 with Snames; use Snames;
72 with Stringt; use Stringt;
73 with Style;
74 with Stylesw; use Stylesw;
75 with Tbuild; use Tbuild;
76 with Uintp; use Uintp;
77 with Urealp; use Urealp;
78 with Validsw; use Validsw;
80 package body Sem_Ch6 is
82 May_Hide_Profile : Boolean := False;
83 -- This flag is used to indicate that two formals in two subprograms being
84 -- checked for conformance differ only in that one is an access parameter
85 -- while the other is of a general access type with the same designated
86 -- type. In this case, if the rest of the signatures match, a call to
87 -- either subprogram may be ambiguous, which is worth a warning. The flag
88 -- is set in Compatible_Types, and the warning emitted in
89 -- New_Overloaded_Entity.
91 -----------------------
92 -- Local Subprograms --
93 -----------------------
95 procedure Analyze_Return_Statement (N : Node_Id);
96 -- Common processing for simple_ and extended_return_statements
98 procedure Analyze_Function_Return (N : Node_Id);
99 -- Subsidiary to Analyze_Return_Statement.
100 -- Called when the return statement applies to a [generic] function.
102 procedure Analyze_Return_Type (N : Node_Id);
103 -- Subsidiary to Process_Formals: analyze subtype mark in function
104 -- specification, in a context where the formals are visible and hide
105 -- outer homographs.
107 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
108 -- Analyze a generic subprogram body. N is the body to be analyzed, and
109 -- Gen_Id is the defining entity Id for the corresponding spec.
111 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
112 -- If a subprogram has pragma Inline and inlining is active, use generic
113 -- machinery to build an unexpanded body for the subprogram. This body is
114 -- subsequenty used for inline expansions at call sites. If subprogram can
115 -- be inlined (depending on size and nature of local declarations) this
116 -- function returns true. Otherwise subprogram body is treated normally.
117 -- If proper warnings are enabled and the subprogram contains a construct
118 -- that cannot be inlined, the offending construct is flagged accordingly.
120 procedure Check_Conformance
121 (New_Id : Entity_Id;
122 Old_Id : Entity_Id;
123 Ctype : Conformance_Type;
124 Errmsg : Boolean;
125 Conforms : out Boolean;
126 Err_Loc : Node_Id := Empty;
127 Get_Inst : Boolean := False;
128 Skip_Controlling_Formals : Boolean := False);
129 -- Given two entities, this procedure checks that the profiles associated
130 -- with these entities meet the conformance criterion given by the third
131 -- parameter. If they conform, Conforms is set True and control returns
132 -- to the caller. If they do not conform, Conforms is set to False, and
133 -- in addition, if Errmsg is True on the call, proper messages are output
134 -- to complain about the conformance failure. If Err_Loc is non_Empty
135 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
136 -- error messages are placed on the appropriate part of the construct
137 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
138 -- against a formal access-to-subprogram type so Get_Instance_Of must
139 -- be called.
141 procedure Check_Overriding_Indicator
142 (Subp : Entity_Id;
143 Overridden_Subp : Entity_Id;
144 Is_Primitive : Boolean);
145 -- Verify the consistency of an overriding_indicator given for subprogram
146 -- declaration, body, renaming, or instantiation. Overridden_Subp is set
147 -- if the scope where we are introducing the subprogram contains a
148 -- type-conformant subprogram that becomes hidden by the new subprogram.
149 -- Is_Primitive indicates whether the subprogram is primitive.
151 procedure Check_Subprogram_Order (N : Node_Id);
152 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
153 -- the alpha ordering rule for N if this ordering requirement applicable.
155 procedure Check_Returns
156 (HSS : Node_Id;
157 Mode : Character;
158 Err : out Boolean;
159 Proc : Entity_Id := Empty);
160 -- Called to check for missing return statements in a function body, or for
161 -- returns present in a procedure body which has No_Return set. HSS is the
162 -- handled statement sequence for the subprogram body. This procedure
163 -- checks all flow paths to make sure they either have return (Mode = 'F',
164 -- used for functions) or do not have a return (Mode = 'P', used for
165 -- No_Return procedures). The flag Err is set if there are any control
166 -- paths not explicitly terminated by a return in the function case, and is
167 -- True otherwise. Proc is the entity for the procedure case and is used
168 -- in posting the warning message.
170 procedure Enter_Overloaded_Entity (S : Entity_Id);
171 -- This procedure makes S, a new overloaded entity, into the first visible
172 -- entity with that name.
174 procedure Install_Entity (E : Entity_Id);
175 -- Make single entity visible. Used for generic formals as well
177 procedure Install_Formals (Id : Entity_Id);
178 -- On entry to a subprogram body, make the formals visible. Note that
179 -- simply placing the subprogram on the scope stack is not sufficient:
180 -- the formals must become the current entities for their names.
182 function Is_Non_Overriding_Operation
183 (Prev_E : Entity_Id;
184 New_E : Entity_Id) return Boolean;
185 -- Enforce the rule given in 12.3(18): a private operation in an instance
186 -- overrides an inherited operation only if the corresponding operation
187 -- was overriding in the generic. This can happen for primitive operations
188 -- of types derived (in the generic unit) from formal private or formal
189 -- derived types.
191 procedure Make_Inequality_Operator (S : Entity_Id);
192 -- Create the declaration for an inequality operator that is implicitly
193 -- created by a user-defined equality operator that yields a boolean.
195 procedure May_Need_Actuals (Fun : Entity_Id);
196 -- Flag functions that can be called without parameters, i.e. those that
197 -- have no parameters, or those for which defaults exist for all parameters
199 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id);
200 -- If there is a separate spec for a subprogram or generic subprogram, the
201 -- formals of the body are treated as references to the corresponding
202 -- formals of the spec. This reference does not count as an actual use of
203 -- the formal, in order to diagnose formals that are unused in the body.
205 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
206 -- Formal_Id is an formal parameter entity. This procedure deals with
207 -- setting the proper validity status for this entity, which depends
208 -- on the kind of parameter and the validity checking mode.
210 ------------------------------
211 -- Analyze_Return_Statement --
212 ------------------------------
214 procedure Analyze_Return_Statement (N : Node_Id) is
216 pragma Assert (Nkind (N) = N_Simple_Return_Statement
217 or else
218 Nkind (N) = N_Extended_Return_Statement);
220 Returns_Object : constant Boolean :=
221 Nkind (N) = N_Extended_Return_Statement
222 or else
223 (Nkind (N) = N_Simple_Return_Statement
224 and then Present (Expression (N)));
225 -- True if we're returning something; that is, "return <expression>;"
226 -- or "return Result : T [:= ...]". False for "return;". Used for error
227 -- checking: If Returns_Object is True, N should apply to a function
228 -- body; otherwise N should apply to a procedure body, entry body,
229 -- accept statement, or extended return statement.
231 function Find_What_It_Applies_To return Entity_Id;
232 -- Find the entity representing the innermost enclosing body, accept
233 -- statement, or extended return statement. If the result is a callable
234 -- construct or extended return statement, then this will be the value
235 -- of the Return_Applies_To attribute. Otherwise, the program is
236 -- illegal. See RM-6.5(4/2).
238 -----------------------------
239 -- Find_What_It_Applies_To --
240 -----------------------------
242 function Find_What_It_Applies_To return Entity_Id is
243 Result : Entity_Id := Empty;
245 begin
246 -- Loop outward through the Scope_Stack, skipping blocks and loops
248 for J in reverse 0 .. Scope_Stack.Last loop
249 Result := Scope_Stack.Table (J).Entity;
250 exit when Ekind (Result) /= E_Block and then
251 Ekind (Result) /= E_Loop;
252 end loop;
254 pragma Assert (Present (Result));
255 return Result;
256 end Find_What_It_Applies_To;
258 -- Local declarations
260 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
261 Kind : constant Entity_Kind := Ekind (Scope_Id);
262 Loc : constant Source_Ptr := Sloc (N);
263 Stm_Entity : constant Entity_Id :=
264 New_Internal_Entity
265 (E_Return_Statement, Current_Scope, Loc, 'R');
267 -- Start of processing for Analyze_Return_Statement
269 begin
270 Set_Return_Statement_Entity (N, Stm_Entity);
272 Set_Etype (Stm_Entity, Standard_Void_Type);
273 Set_Return_Applies_To (Stm_Entity, Scope_Id);
275 -- Place Return entity on scope stack, to simplify enforcement of 6.5
276 -- (4/2): an inner return statement will apply to this extended return.
278 if Nkind (N) = N_Extended_Return_Statement then
279 Push_Scope (Stm_Entity);
280 end if;
282 -- Check that pragma No_Return is obeyed
284 if No_Return (Scope_Id) then
285 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
286 end if;
288 -- Warn on any unassigned OUT parameters if in procedure
290 if Ekind (Scope_Id) = E_Procedure then
291 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
292 end if;
294 -- Check that functions return objects, and other things do not
296 if Kind = E_Function or else Kind = E_Generic_Function then
297 if not Returns_Object then
298 Error_Msg_N ("missing expression in return from function", N);
299 end if;
301 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
302 if Returns_Object then
303 Error_Msg_N ("procedure cannot return value (use function)", N);
304 end if;
306 elsif Kind = E_Entry or else Kind = E_Entry_Family then
307 if Returns_Object then
308 if Is_Protected_Type (Scope (Scope_Id)) then
309 Error_Msg_N ("entry body cannot return value", N);
310 else
311 Error_Msg_N ("accept statement cannot return value", N);
312 end if;
313 end if;
315 elsif Kind = E_Return_Statement then
317 -- We are nested within another return statement, which must be an
318 -- extended_return_statement.
320 if Returns_Object then
321 Error_Msg_N
322 ("extended_return_statement cannot return value; " &
323 "use `""RETURN;""`", N);
324 end if;
326 else
327 Error_Msg_N ("illegal context for return statement", N);
328 end if;
330 if Kind = E_Function or else Kind = E_Generic_Function then
331 Analyze_Function_Return (N);
332 end if;
334 if Nkind (N) = N_Extended_Return_Statement then
335 End_Scope;
336 end if;
338 Check_Unreachable_Code (N);
339 end Analyze_Return_Statement;
341 ---------------------------------------------
342 -- Analyze_Abstract_Subprogram_Declaration --
343 ---------------------------------------------
345 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
346 Designator : constant Entity_Id :=
347 Analyze_Subprogram_Specification (Specification (N));
348 Scop : constant Entity_Id := Current_Scope;
350 begin
351 Generate_Definition (Designator);
352 Set_Is_Abstract_Subprogram (Designator);
353 New_Overloaded_Entity (Designator);
354 Check_Delayed_Subprogram (Designator);
356 Set_Categorization_From_Scope (Designator, Scop);
358 if Ekind (Scope (Designator)) = E_Protected_Type then
359 Error_Msg_N
360 ("abstract subprogram not allowed in protected type", N);
362 -- Issue a warning if the abstract subprogram is neither a dispatching
363 -- operation nor an operation that overrides an inherited subprogram or
364 -- predefined operator, since this most likely indicates a mistake.
366 elsif Warn_On_Redundant_Constructs
367 and then not Is_Dispatching_Operation (Designator)
368 and then not Is_Overriding_Operation (Designator)
369 and then (not Is_Operator_Symbol_Name (Chars (Designator))
370 or else Scop /= Scope (Etype (First_Formal (Designator))))
371 then
372 Error_Msg_N
373 ("?abstract subprogram is not dispatching or overriding", N);
374 end if;
376 Generate_Reference_To_Formals (Designator);
377 end Analyze_Abstract_Subprogram_Declaration;
379 ----------------------------------------
380 -- Analyze_Extended_Return_Statement --
381 ----------------------------------------
383 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
384 begin
385 Analyze_Return_Statement (N);
386 end Analyze_Extended_Return_Statement;
388 ----------------------------
389 -- Analyze_Function_Call --
390 ----------------------------
392 procedure Analyze_Function_Call (N : Node_Id) is
393 P : constant Node_Id := Name (N);
394 L : constant List_Id := Parameter_Associations (N);
395 Actual : Node_Id;
397 begin
398 Analyze (P);
400 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
401 -- as B (A, X). If the rewriting is successful, the call has been
402 -- analyzed and we just return.
404 if Nkind (P) = N_Selected_Component
405 and then Name (N) /= P
406 and then Is_Rewrite_Substitution (N)
407 and then Present (Etype (N))
408 then
409 return;
410 end if;
412 -- If error analyzing name, then set Any_Type as result type and return
414 if Etype (P) = Any_Type then
415 Set_Etype (N, Any_Type);
416 return;
417 end if;
419 -- Otherwise analyze the parameters
421 if Present (L) then
422 Actual := First (L);
423 while Present (Actual) loop
424 Analyze (Actual);
425 Check_Parameterless_Call (Actual);
426 Next (Actual);
427 end loop;
428 end if;
430 Analyze_Call (N);
431 end Analyze_Function_Call;
433 -----------------------------
434 -- Analyze_Function_Return --
435 -----------------------------
437 procedure Analyze_Function_Return (N : Node_Id) is
438 Loc : constant Source_Ptr := Sloc (N);
439 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
440 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
442 R_Type : constant Entity_Id := Etype (Scope_Id);
443 -- Function result subtype
445 procedure Check_Limited_Return (Expr : Node_Id);
446 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
447 -- limited types. Used only for simple return statements.
448 -- Expr is the expression returned.
450 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
451 -- Check that the return_subtype_indication properly matches the result
452 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
454 --------------------------
455 -- Check_Limited_Return --
456 --------------------------
458 procedure Check_Limited_Return (Expr : Node_Id) is
459 begin
460 -- Ada 2005 (AI-318-02): Return-by-reference types have been
461 -- removed and replaced by anonymous access results. This is an
462 -- incompatibility with Ada 95. Not clear whether this should be
463 -- enforced yet or perhaps controllable with special switch. ???
465 if Is_Limited_Type (R_Type)
466 and then Comes_From_Source (N)
467 and then not In_Instance_Body
468 and then not OK_For_Limited_Init_In_05 (Expr)
469 then
470 -- Error in Ada 2005
472 if Ada_Version >= Ada_05
473 and then not Debug_Flag_Dot_L
474 and then not GNAT_Mode
475 then
476 Error_Msg_N
477 ("(Ada 2005) cannot copy object of a limited type " &
478 "(RM-2005 6.5(5.5/2))", Expr);
479 if Is_Inherently_Limited_Type (R_Type) then
480 Error_Msg_N
481 ("\return by reference not permitted in Ada 2005", Expr);
482 end if;
484 -- Warn in Ada 95 mode, to give folks a heads up about this
485 -- incompatibility.
487 -- In GNAT mode, this is just a warning, to allow it to be
488 -- evilly turned off. Otherwise it is a real error.
490 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
491 if Is_Inherently_Limited_Type (R_Type) then
492 Error_Msg_N
493 ("return by reference not permitted in Ada 2005 " &
494 "(RM-2005 6.5(5.5/2))?", Expr);
495 else
496 Error_Msg_N
497 ("cannot copy object of a limited type in Ada 2005 " &
498 "(RM-2005 6.5(5.5/2))?", Expr);
499 end if;
501 -- Ada 95 mode, compatibility warnings disabled
503 else
504 return; -- skip continuation messages below
505 end if;
507 Error_Msg_N
508 ("\consider switching to return of access type", Expr);
509 Explain_Limited_Type (R_Type, Expr);
510 end if;
511 end Check_Limited_Return;
513 -------------------------------------
514 -- Check_Return_Subtype_Indication --
515 -------------------------------------
517 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
518 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
519 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
520 -- Subtype given in the extended return statement;
521 -- this must match R_Type.
523 Subtype_Ind : constant Node_Id :=
524 Object_Definition (Original_Node (Obj_Decl));
526 R_Type_Is_Anon_Access :
527 constant Boolean :=
528 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
529 or else
530 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
531 or else
532 Ekind (R_Type) = E_Anonymous_Access_Type;
533 -- True if return type of the function is an anonymous access type
534 -- Can't we make Is_Anonymous_Access_Type in einfo ???
536 R_Stm_Type_Is_Anon_Access :
537 constant Boolean :=
538 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
539 or else
540 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
541 or else
542 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
543 -- True if type of the return object is an anonymous access type
545 begin
546 -- First, avoid cascade errors:
548 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
549 return;
550 end if;
552 -- "return access T" case; check that the return statement also has
553 -- "access T", and that the subtypes statically match:
555 if R_Type_Is_Anon_Access then
556 if R_Stm_Type_Is_Anon_Access then
557 if Base_Type (Designated_Type (R_Stm_Type)) /=
558 Base_Type (Designated_Type (R_Type))
559 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
560 then
561 Error_Msg_N
562 ("subtype must statically match function result subtype",
563 Subtype_Mark (Subtype_Ind));
564 end if;
566 else
567 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
568 end if;
570 -- Subtype_indication case; check that the types are the same, and
571 -- statically match if appropriate:
573 elsif Base_Type (R_Stm_Type) = Base_Type (R_Type) then
574 if Is_Constrained (R_Type) then
575 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
576 Error_Msg_N
577 ("subtype must statically match function result subtype",
578 Subtype_Ind);
579 end if;
580 end if;
582 -- If the function's result type doesn't match the return object
583 -- entity's type, then we check for the case where the result type
584 -- is class-wide, and allow the declaration if the type of the object
585 -- definition matches the class-wide type. This prevents rejection
586 -- in the case where the object declaration is initialized by a call
587 -- to a build-in-place function with a specific result type and the
588 -- object entity had its type changed to that specific type. (Note
589 -- that the ARG believes that return objects should be allowed to
590 -- have a type covered by a class-wide result type in any case, so
591 -- once that relaxation is made (see AI05-32), the above check for
592 -- type compatibility should be changed to test Covers rather than
593 -- equality, and then the following special test will no longer be
594 -- needed. ???)
596 elsif Is_Class_Wide_Type (R_Type)
597 and then
598 R_Type = Etype (Object_Definition (Original_Node (Obj_Decl)))
599 then
600 null;
602 else
603 Error_Msg_N
604 ("wrong type for return_subtype_indication", Subtype_Ind);
605 end if;
606 end Check_Return_Subtype_Indication;
608 ---------------------
609 -- Local Variables --
610 ---------------------
612 Expr : Node_Id;
614 -- Start of processing for Analyze_Function_Return
616 begin
617 Set_Return_Present (Scope_Id);
619 if Nkind (N) = N_Simple_Return_Statement then
620 Expr := Expression (N);
621 Analyze_And_Resolve (Expr, R_Type);
622 Check_Limited_Return (Expr);
624 else
625 -- Analyze parts specific to extended_return_statement:
627 declare
628 Obj_Decl : constant Node_Id :=
629 Last (Return_Object_Declarations (N));
631 HSS : constant Node_Id := Handled_Statement_Sequence (N);
633 begin
634 Expr := Expression (Obj_Decl);
636 -- Note: The check for OK_For_Limited_Init will happen in
637 -- Analyze_Object_Declaration; we treat it as a normal
638 -- object declaration.
640 Analyze (Obj_Decl);
642 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
643 Check_Return_Subtype_Indication (Obj_Decl);
645 if Present (HSS) then
646 Analyze (HSS);
648 if Present (Exception_Handlers (HSS)) then
650 -- ???Has_Nested_Block_With_Handler needs to be set.
651 -- Probably by creating an actual N_Block_Statement.
652 -- Probably in Expand.
654 null;
655 end if;
656 end if;
658 Check_References (Stm_Entity);
659 end;
660 end if;
662 -- Case of Expr present (Etype check defends against previous errors)
664 if Present (Expr)
665 and then Present (Etype (Expr))
666 then
667 -- Apply constraint check. Note that this is done before the implicit
668 -- conversion of the expression done for anonymous access types to
669 -- ensure correct generation of the null-excluding check asssociated
670 -- with null-excluding expressions found in return statements.
672 Apply_Constraint_Check (Expr, R_Type);
674 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
675 -- type, apply an implicit conversion of the expression to that type
676 -- to force appropriate static and run-time accessibility checks.
678 if Ada_Version >= Ada_05
679 and then Ekind (R_Type) = E_Anonymous_Access_Type
680 then
681 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
682 Analyze_And_Resolve (Expr, R_Type);
683 end if;
685 if (Is_Class_Wide_Type (Etype (Expr))
686 or else Is_Dynamically_Tagged (Expr))
687 and then not Is_Class_Wide_Type (R_Type)
688 then
689 Error_Msg_N
690 ("dynamically tagged expression not allowed!", Expr);
691 end if;
693 -- ??? A real run-time accessibility check is needed in cases
694 -- involving dereferences of access parameters. For now we just
695 -- check the static cases.
697 if (Ada_Version < Ada_05 or else Debug_Flag_Dot_L)
698 and then Is_Inherently_Limited_Type (Etype (Scope_Id))
699 and then Object_Access_Level (Expr) >
700 Subprogram_Access_Level (Scope_Id)
701 then
702 Rewrite (N,
703 Make_Raise_Program_Error (Loc,
704 Reason => PE_Accessibility_Check_Failed));
705 Analyze (N);
707 Error_Msg_N
708 ("cannot return a local value by reference?", N);
709 Error_Msg_NE
710 ("\& will be raised at run time?",
711 N, Standard_Program_Error);
712 end if;
714 if Known_Null (Expr)
715 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
716 and then Null_Exclusion_Present (Parent (Scope_Id))
717 then
718 Apply_Compile_Time_Constraint_Error
719 (N => Expr,
720 Msg => "(Ada 2005) null not allowed for "
721 & "null-excluding return?",
722 Reason => CE_Null_Not_Allowed);
723 end if;
724 end if;
725 end Analyze_Function_Return;
727 -------------------------------------
728 -- Analyze_Generic_Subprogram_Body --
729 -------------------------------------
731 procedure Analyze_Generic_Subprogram_Body
732 (N : Node_Id;
733 Gen_Id : Entity_Id)
735 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
736 Kind : constant Entity_Kind := Ekind (Gen_Id);
737 Body_Id : Entity_Id;
738 New_N : Node_Id;
739 Spec : Node_Id;
741 begin
742 -- Copy body and disable expansion while analyzing the generic For a
743 -- stub, do not copy the stub (which would load the proper body), this
744 -- will be done when the proper body is analyzed.
746 if Nkind (N) /= N_Subprogram_Body_Stub then
747 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
748 Rewrite (N, New_N);
749 Start_Generic;
750 end if;
752 Spec := Specification (N);
754 -- Within the body of the generic, the subprogram is callable, and
755 -- behaves like the corresponding non-generic unit.
757 Body_Id := Defining_Entity (Spec);
759 if Kind = E_Generic_Procedure
760 and then Nkind (Spec) /= N_Procedure_Specification
761 then
762 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
763 return;
765 elsif Kind = E_Generic_Function
766 and then Nkind (Spec) /= N_Function_Specification
767 then
768 Error_Msg_N ("invalid body for generic function ", Body_Id);
769 return;
770 end if;
772 Set_Corresponding_Body (Gen_Decl, Body_Id);
774 if Has_Completion (Gen_Id)
775 and then Nkind (Parent (N)) /= N_Subunit
776 then
777 Error_Msg_N ("duplicate generic body", N);
778 return;
779 else
780 Set_Has_Completion (Gen_Id);
781 end if;
783 if Nkind (N) = N_Subprogram_Body_Stub then
784 Set_Ekind (Defining_Entity (Specification (N)), Kind);
785 else
786 Set_Corresponding_Spec (N, Gen_Id);
787 end if;
789 if Nkind (Parent (N)) = N_Compilation_Unit then
790 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
791 end if;
793 -- Make generic parameters immediately visible in the body. They are
794 -- needed to process the formals declarations. Then make the formals
795 -- visible in a separate step.
797 Push_Scope (Gen_Id);
799 declare
800 E : Entity_Id;
801 First_Ent : Entity_Id;
803 begin
804 First_Ent := First_Entity (Gen_Id);
806 E := First_Ent;
807 while Present (E) and then not Is_Formal (E) loop
808 Install_Entity (E);
809 Next_Entity (E);
810 end loop;
812 Set_Use (Generic_Formal_Declarations (Gen_Decl));
814 -- Now generic formals are visible, and the specification can be
815 -- analyzed, for subsequent conformance check.
817 Body_Id := Analyze_Subprogram_Specification (Spec);
819 -- Make formal parameters visible
821 if Present (E) then
823 -- E is the first formal parameter, we loop through the formals
824 -- installing them so that they will be visible.
826 Set_First_Entity (Gen_Id, E);
827 while Present (E) loop
828 Install_Entity (E);
829 Next_Formal (E);
830 end loop;
831 end if;
833 -- Visible generic entity is callable within its own body
835 Set_Ekind (Gen_Id, Ekind (Body_Id));
836 Set_Ekind (Body_Id, E_Subprogram_Body);
837 Set_Convention (Body_Id, Convention (Gen_Id));
838 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
839 Set_Scope (Body_Id, Scope (Gen_Id));
840 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
842 if Nkind (N) = N_Subprogram_Body_Stub then
844 -- No body to analyze, so restore state of generic unit
846 Set_Ekind (Gen_Id, Kind);
847 Set_Ekind (Body_Id, Kind);
849 if Present (First_Ent) then
850 Set_First_Entity (Gen_Id, First_Ent);
851 end if;
853 End_Scope;
854 return;
855 end if;
857 -- If this is a compilation unit, it must be made visible explicitly,
858 -- because the compilation of the declaration, unlike other library
859 -- unit declarations, does not. If it is not a unit, the following
860 -- is redundant but harmless.
862 Set_Is_Immediately_Visible (Gen_Id);
863 Reference_Body_Formals (Gen_Id, Body_Id);
865 if Is_Child_Unit (Gen_Id) then
866 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
867 end if;
869 Set_Actual_Subtypes (N, Current_Scope);
870 Analyze_Declarations (Declarations (N));
871 Check_Completion;
872 Analyze (Handled_Statement_Sequence (N));
874 Save_Global_References (Original_Node (N));
876 -- Prior to exiting the scope, include generic formals again (if any
877 -- are present) in the set of local entities.
879 if Present (First_Ent) then
880 Set_First_Entity (Gen_Id, First_Ent);
881 end if;
883 Check_References (Gen_Id);
884 end;
886 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
887 End_Scope;
888 Check_Subprogram_Order (N);
890 -- Outside of its body, unit is generic again
892 Set_Ekind (Gen_Id, Kind);
893 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
895 if Style_Check then
896 Style.Check_Identifier (Body_Id, Gen_Id);
897 end if;
898 End_Generic;
899 end Analyze_Generic_Subprogram_Body;
901 -----------------------------
902 -- Analyze_Operator_Symbol --
903 -----------------------------
905 -- An operator symbol such as "+" or "and" may appear in context where the
906 -- literal denotes an entity name, such as "+"(x, y) or in context when it
907 -- is just a string, as in (conjunction = "or"). In these cases the parser
908 -- generates this node, and the semantics does the disambiguation. Other
909 -- such case are actuals in an instantiation, the generic unit in an
910 -- instantiation, and pragma arguments.
912 procedure Analyze_Operator_Symbol (N : Node_Id) is
913 Par : constant Node_Id := Parent (N);
915 begin
916 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
917 or else Nkind (Par) = N_Function_Instantiation
918 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
919 or else (Nkind (Par) = N_Pragma_Argument_Association
920 and then not Is_Pragma_String_Literal (Par))
921 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
922 or else (Nkind (Par) = N_Attribute_Reference
923 and then Attribute_Name (Par) /= Name_Value)
924 then
925 Find_Direct_Name (N);
927 else
928 Change_Operator_Symbol_To_String_Literal (N);
929 Analyze (N);
930 end if;
931 end Analyze_Operator_Symbol;
933 -----------------------------------
934 -- Analyze_Parameter_Association --
935 -----------------------------------
937 procedure Analyze_Parameter_Association (N : Node_Id) is
938 begin
939 Analyze (Explicit_Actual_Parameter (N));
940 end Analyze_Parameter_Association;
942 ----------------------------
943 -- Analyze_Procedure_Call --
944 ----------------------------
946 procedure Analyze_Procedure_Call (N : Node_Id) is
947 Loc : constant Source_Ptr := Sloc (N);
948 P : constant Node_Id := Name (N);
949 Actuals : constant List_Id := Parameter_Associations (N);
950 Actual : Node_Id;
951 New_N : Node_Id;
953 procedure Analyze_Call_And_Resolve;
954 -- Do Analyze and Resolve calls for procedure call
956 ------------------------------
957 -- Analyze_Call_And_Resolve --
958 ------------------------------
960 procedure Analyze_Call_And_Resolve is
961 begin
962 if Nkind (N) = N_Procedure_Call_Statement then
963 Analyze_Call (N);
964 Resolve (N, Standard_Void_Type);
965 else
966 Analyze (N);
967 end if;
968 end Analyze_Call_And_Resolve;
970 -- Start of processing for Analyze_Procedure_Call
972 begin
973 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
974 -- a procedure call or an entry call. The prefix may denote an access
975 -- to subprogram type, in which case an implicit dereference applies.
976 -- If the prefix is an indexed component (without implicit defererence)
977 -- then the construct denotes a call to a member of an entire family.
978 -- If the prefix is a simple name, it may still denote a call to a
979 -- parameterless member of an entry family. Resolution of these various
980 -- interpretations is delicate.
982 Analyze (P);
984 -- If this is a call of the form Obj.Op, the call may have been
985 -- analyzed and possibly rewritten into a block, in which case
986 -- we are done.
988 if Analyzed (N) then
989 return;
990 end if;
992 -- If error analyzing prefix, then set Any_Type as result and return
994 if Etype (P) = Any_Type then
995 Set_Etype (N, Any_Type);
996 return;
997 end if;
999 -- Otherwise analyze the parameters
1001 if Present (Actuals) then
1002 Actual := First (Actuals);
1004 while Present (Actual) loop
1005 Analyze (Actual);
1006 Check_Parameterless_Call (Actual);
1007 Next (Actual);
1008 end loop;
1009 end if;
1011 -- Special processing for Elab_Spec and Elab_Body calls
1013 if Nkind (P) = N_Attribute_Reference
1014 and then (Attribute_Name (P) = Name_Elab_Spec
1015 or else Attribute_Name (P) = Name_Elab_Body)
1016 then
1017 if Present (Actuals) then
1018 Error_Msg_N
1019 ("no parameters allowed for this call", First (Actuals));
1020 return;
1021 end if;
1023 Set_Etype (N, Standard_Void_Type);
1024 Set_Analyzed (N);
1026 elsif Is_Entity_Name (P)
1027 and then Is_Record_Type (Etype (Entity (P)))
1028 and then Remote_AST_I_Dereference (P)
1029 then
1030 return;
1032 elsif Is_Entity_Name (P)
1033 and then Ekind (Entity (P)) /= E_Entry_Family
1034 then
1035 if Is_Access_Type (Etype (P))
1036 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1037 and then No (Actuals)
1038 and then Comes_From_Source (N)
1039 then
1040 Error_Msg_N ("missing explicit dereference in call", N);
1041 end if;
1043 Analyze_Call_And_Resolve;
1045 -- If the prefix is the simple name of an entry family, this is
1046 -- a parameterless call from within the task body itself.
1048 elsif Is_Entity_Name (P)
1049 and then Nkind (P) = N_Identifier
1050 and then Ekind (Entity (P)) = E_Entry_Family
1051 and then Present (Actuals)
1052 and then No (Next (First (Actuals)))
1053 then
1054 -- Can be call to parameterless entry family. What appears to be the
1055 -- sole argument is in fact the entry index. Rewrite prefix of node
1056 -- accordingly. Source representation is unchanged by this
1057 -- transformation.
1059 New_N :=
1060 Make_Indexed_Component (Loc,
1061 Prefix =>
1062 Make_Selected_Component (Loc,
1063 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1064 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1065 Expressions => Actuals);
1066 Set_Name (N, New_N);
1067 Set_Etype (New_N, Standard_Void_Type);
1068 Set_Parameter_Associations (N, No_List);
1069 Analyze_Call_And_Resolve;
1071 elsif Nkind (P) = N_Explicit_Dereference then
1072 if Ekind (Etype (P)) = E_Subprogram_Type then
1073 Analyze_Call_And_Resolve;
1074 else
1075 Error_Msg_N ("expect access to procedure in call", P);
1076 end if;
1078 -- The name can be a selected component or an indexed component that
1079 -- yields an access to subprogram. Such a prefix is legal if the call
1080 -- has parameter associations.
1082 elsif Is_Access_Type (Etype (P))
1083 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1084 then
1085 if Present (Actuals) then
1086 Analyze_Call_And_Resolve;
1087 else
1088 Error_Msg_N ("missing explicit dereference in call ", N);
1089 end if;
1091 -- If not an access to subprogram, then the prefix must resolve to the
1092 -- name of an entry, entry family, or protected operation.
1094 -- For the case of a simple entry call, P is a selected component where
1095 -- the prefix is the task and the selector name is the entry. A call to
1096 -- a protected procedure will have the same syntax. If the protected
1097 -- object contains overloaded operations, the entity may appear as a
1098 -- function, the context will select the operation whose type is Void.
1100 elsif Nkind (P) = N_Selected_Component
1101 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1102 or else
1103 Ekind (Entity (Selector_Name (P))) = E_Procedure
1104 or else
1105 Ekind (Entity (Selector_Name (P))) = E_Function)
1106 then
1107 Analyze_Call_And_Resolve;
1109 elsif Nkind (P) = N_Selected_Component
1110 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1111 and then Present (Actuals)
1112 and then No (Next (First (Actuals)))
1113 then
1114 -- Can be call to parameterless entry family. What appears to be the
1115 -- sole argument is in fact the entry index. Rewrite prefix of node
1116 -- accordingly. Source representation is unchanged by this
1117 -- transformation.
1119 New_N :=
1120 Make_Indexed_Component (Loc,
1121 Prefix => New_Copy (P),
1122 Expressions => Actuals);
1123 Set_Name (N, New_N);
1124 Set_Etype (New_N, Standard_Void_Type);
1125 Set_Parameter_Associations (N, No_List);
1126 Analyze_Call_And_Resolve;
1128 -- For the case of a reference to an element of an entry family, P is
1129 -- an indexed component whose prefix is a selected component (task and
1130 -- entry family), and whose index is the entry family index.
1132 elsif Nkind (P) = N_Indexed_Component
1133 and then Nkind (Prefix (P)) = N_Selected_Component
1134 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1135 then
1136 Analyze_Call_And_Resolve;
1138 -- If the prefix is the name of an entry family, it is a call from
1139 -- within the task body itself.
1141 elsif Nkind (P) = N_Indexed_Component
1142 and then Nkind (Prefix (P)) = N_Identifier
1143 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1144 then
1145 New_N :=
1146 Make_Selected_Component (Loc,
1147 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1148 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1149 Rewrite (Prefix (P), New_N);
1150 Analyze (P);
1151 Analyze_Call_And_Resolve;
1153 -- Anything else is an error
1155 else
1156 Error_Msg_N ("invalid procedure or entry call", N);
1157 end if;
1158 end Analyze_Procedure_Call;
1160 -------------------------------------
1161 -- Analyze_Simple_Return_Statement --
1162 -------------------------------------
1164 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1165 begin
1166 if Present (Expression (N)) then
1167 Mark_Coextensions (N, Expression (N));
1168 end if;
1170 Analyze_Return_Statement (N);
1171 end Analyze_Simple_Return_Statement;
1173 -------------------------
1174 -- Analyze_Return_Type --
1175 -------------------------
1177 procedure Analyze_Return_Type (N : Node_Id) is
1178 Designator : constant Entity_Id := Defining_Entity (N);
1179 Typ : Entity_Id := Empty;
1181 begin
1182 -- Normal case where result definition does not indicate an error
1184 if Result_Definition (N) /= Error then
1185 if Nkind (Result_Definition (N)) = N_Access_Definition then
1186 Typ := Access_Definition (N, Result_Definition (N));
1187 Set_Parent (Typ, Result_Definition (N));
1188 Set_Is_Local_Anonymous_Access (Typ);
1189 Set_Etype (Designator, Typ);
1191 -- Subtype_Mark case
1193 else
1194 Find_Type (Result_Definition (N));
1195 Typ := Entity (Result_Definition (N));
1196 Set_Etype (Designator, Typ);
1198 if Ekind (Typ) = E_Incomplete_Type
1199 and then Is_Value_Type (Typ)
1200 then
1201 null;
1203 elsif Ekind (Typ) = E_Incomplete_Type
1204 or else (Is_Class_Wide_Type (Typ)
1205 and then
1206 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1207 then
1208 Error_Msg_N
1209 ("invalid use of incomplete type", Result_Definition (N));
1210 end if;
1211 end if;
1213 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1215 Null_Exclusion_Static_Checks (N);
1217 -- Case where result definition does indicate an error
1219 else
1220 Set_Etype (Designator, Any_Type);
1221 end if;
1222 end Analyze_Return_Type;
1224 -----------------------------
1225 -- Analyze_Subprogram_Body --
1226 -----------------------------
1228 -- This procedure is called for regular subprogram bodies, generic bodies,
1229 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1230 -- specification matters, and is used to create a proper declaration for
1231 -- the subprogram, or to perform conformance checks.
1233 procedure Analyze_Subprogram_Body (N : Node_Id) is
1234 Loc : constant Source_Ptr := Sloc (N);
1235 Body_Spec : constant Node_Id := Specification (N);
1236 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1237 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1238 Body_Deleted : constant Boolean := False;
1240 HSS : Node_Id;
1241 Spec_Id : Entity_Id;
1242 Spec_Decl : Node_Id := Empty;
1243 Last_Formal : Entity_Id := Empty;
1244 Conformant : Boolean;
1245 Missing_Ret : Boolean;
1246 P_Ent : Entity_Id;
1248 procedure Check_Anonymous_Return;
1249 -- (Ada 2005): if a function returns an access type that denotes a task,
1250 -- or a type that contains tasks, we must create a master entity for
1251 -- the anonymous type, which typically will be used in an allocator
1252 -- in the body of the function.
1254 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1255 -- Look ahead to recognize a pragma that may appear after the body.
1256 -- If there is a previous spec, check that it appears in the same
1257 -- declarative part. If the pragma is Inline_Always, perform inlining
1258 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1259 -- If the body acts as a spec, and inlining is required, we create a
1260 -- subprogram declaration for it, in order to attach the body to inline.
1262 procedure Copy_Parameter_List (Plist : List_Id);
1263 -- Utility to create a parameter profile for a new subprogram spec,
1264 -- when the subprogram has a body that acts as spec. This is done for
1265 -- some cases of inlining, and for private protected ops.
1267 procedure Verify_Overriding_Indicator;
1268 -- If there was a previous spec, the entity has been entered in the
1269 -- current scope previously. If the body itself carries an overriding
1270 -- indicator, check that it is consistent with the known status of the
1271 -- entity.
1273 ----------------------------
1274 -- Check_Anonymous_Return --
1275 ----------------------------
1277 procedure Check_Anonymous_Return is
1278 Decl : Node_Id;
1279 Scop : Entity_Id;
1281 begin
1282 if Present (Spec_Id) then
1283 Scop := Spec_Id;
1284 else
1285 Scop := Body_Id;
1286 end if;
1288 if Ekind (Scop) = E_Function
1289 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1290 and then Has_Task (Designated_Type (Etype (Scop)))
1291 and then Expander_Active
1292 then
1293 Decl :=
1294 Make_Object_Declaration (Loc,
1295 Defining_Identifier =>
1296 Make_Defining_Identifier (Loc, Name_uMaster),
1297 Constant_Present => True,
1298 Object_Definition =>
1299 New_Reference_To (RTE (RE_Master_Id), Loc),
1300 Expression =>
1301 Make_Explicit_Dereference (Loc,
1302 New_Reference_To (RTE (RE_Current_Master), Loc)));
1304 if Present (Declarations (N)) then
1305 Prepend (Decl, Declarations (N));
1306 else
1307 Set_Declarations (N, New_List (Decl));
1308 end if;
1310 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1311 Set_Has_Master_Entity (Scop);
1312 end if;
1313 end Check_Anonymous_Return;
1315 -------------------------
1316 -- Check_Inline_Pragma --
1317 -------------------------
1319 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1320 Prag : Node_Id;
1321 Plist : List_Id;
1323 begin
1324 if not Expander_Active then
1325 return;
1326 end if;
1328 if Is_List_Member (N)
1329 and then Present (Next (N))
1330 and then Nkind (Next (N)) = N_Pragma
1331 then
1332 Prag := Next (N);
1334 if Nkind (Prag) = N_Pragma
1335 and then
1336 (Get_Pragma_Id (Chars (Prag)) = Pragma_Inline_Always
1337 or else
1338 (Front_End_Inlining
1339 and then Get_Pragma_Id (Chars (Prag)) = Pragma_Inline))
1340 and then
1341 Chars
1342 (Expression (First (Pragma_Argument_Associations (Prag))))
1343 = Chars (Body_Id)
1344 then
1345 Prag := Next (N);
1346 else
1347 Prag := Empty;
1348 end if;
1349 else
1350 Prag := Empty;
1351 end if;
1353 if Present (Prag) then
1354 if Present (Spec_Id) then
1355 if List_Containing (N) =
1356 List_Containing (Unit_Declaration_Node (Spec_Id))
1357 then
1358 Analyze (Prag);
1359 end if;
1361 else
1362 -- Create a subprogram declaration, to make treatment uniform
1364 declare
1365 Subp : constant Entity_Id :=
1366 Make_Defining_Identifier (Loc, Chars (Body_Id));
1367 Decl : constant Node_Id :=
1368 Make_Subprogram_Declaration (Loc,
1369 Specification => New_Copy_Tree (Specification (N)));
1370 begin
1371 Set_Defining_Unit_Name (Specification (Decl), Subp);
1373 if Present (First_Formal (Body_Id)) then
1374 Plist := New_List;
1375 Copy_Parameter_List (Plist);
1376 Set_Parameter_Specifications
1377 (Specification (Decl), Plist);
1378 end if;
1380 Insert_Before (N, Decl);
1381 Analyze (Decl);
1382 Analyze (Prag);
1383 Set_Has_Pragma_Inline (Subp);
1385 if Get_Pragma_Id (Chars (Prag)) = Pragma_Inline_Always then
1386 Set_Is_Inlined (Subp);
1387 Set_Next_Rep_Item (Prag, First_Rep_Item (Subp));
1388 Set_First_Rep_Item (Subp, Prag);
1389 end if;
1391 Spec := Subp;
1392 end;
1393 end if;
1394 end if;
1395 end Check_Inline_Pragma;
1397 -------------------------
1398 -- Copy_Parameter_List --
1399 -------------------------
1401 procedure Copy_Parameter_List (Plist : List_Id) is
1402 Formal : Entity_Id;
1404 begin
1405 Formal := First_Formal (Body_Id);
1407 while Present (Formal) loop
1408 Append
1409 (Make_Parameter_Specification (Loc,
1410 Defining_Identifier =>
1411 Make_Defining_Identifier (Sloc (Formal),
1412 Chars => Chars (Formal)),
1413 In_Present => In_Present (Parent (Formal)),
1414 Out_Present => Out_Present (Parent (Formal)),
1415 Parameter_Type =>
1416 New_Reference_To (Etype (Formal), Loc),
1417 Expression =>
1418 New_Copy_Tree (Expression (Parent (Formal)))),
1419 Plist);
1421 Next_Formal (Formal);
1422 end loop;
1423 end Copy_Parameter_List;
1425 ---------------------------------
1426 -- Verify_Overriding_Indicator --
1427 ---------------------------------
1429 procedure Verify_Overriding_Indicator is
1430 begin
1431 if Must_Override (Body_Spec)
1432 and then not Is_Overriding_Operation (Spec_Id)
1433 then
1434 Error_Msg_NE
1435 ("subprogram& is not overriding", Body_Spec, Spec_Id);
1437 elsif Must_Not_Override (Body_Spec) then
1438 if Is_Overriding_Operation (Spec_Id) then
1439 Error_Msg_NE
1440 ("subprogram& overrides inherited operation",
1441 Body_Spec, Spec_Id);
1443 -- If this is not a primitive operation the overriding indicator
1444 -- is altogether illegal.
1446 elsif not Is_Primitive (Spec_Id) then
1447 Error_Msg_N ("overriding indicator only allowed " &
1448 "if subprogram is primitive",
1449 Body_Spec);
1450 end if;
1451 end if;
1452 end Verify_Overriding_Indicator;
1454 -- Start of processing for Analyze_Subprogram_Body
1456 begin
1457 if Debug_Flag_C then
1458 Write_Str ("==== Compiling subprogram body ");
1459 Write_Name (Chars (Body_Id));
1460 Write_Str (" from ");
1461 Write_Location (Loc);
1462 Write_Eol;
1463 end if;
1465 Trace_Scope (N, Body_Id, " Analyze subprogram");
1467 -- Generic subprograms are handled separately. They always have a
1468 -- generic specification. Determine whether current scope has a
1469 -- previous declaration.
1471 -- If the subprogram body is defined within an instance of the same
1472 -- name, the instance appears as a package renaming, and will be hidden
1473 -- within the subprogram.
1475 if Present (Prev_Id)
1476 and then not Is_Overloadable (Prev_Id)
1477 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
1478 or else Comes_From_Source (Prev_Id))
1479 then
1480 if Is_Generic_Subprogram (Prev_Id) then
1481 Spec_Id := Prev_Id;
1482 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1483 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1485 Analyze_Generic_Subprogram_Body (N, Spec_Id);
1486 return;
1488 else
1489 -- Previous entity conflicts with subprogram name. Attempting to
1490 -- enter name will post error.
1492 Enter_Name (Body_Id);
1493 return;
1494 end if;
1496 -- Non-generic case, find the subprogram declaration, if one was seen,
1497 -- or enter new overloaded entity in the current scope. If the
1498 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
1499 -- part of the context of one of its subunits. No need to redo the
1500 -- analysis.
1502 elsif Prev_Id = Body_Id
1503 and then Has_Completion (Body_Id)
1504 then
1505 return;
1507 else
1508 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
1510 if Nkind (N) = N_Subprogram_Body_Stub
1511 or else No (Corresponding_Spec (N))
1512 then
1513 Spec_Id := Find_Corresponding_Spec (N);
1515 -- If this is a duplicate body, no point in analyzing it
1517 if Error_Posted (N) then
1518 return;
1519 end if;
1521 -- A subprogram body should cause freezing of its own declaration,
1522 -- but if there was no previous explicit declaration, then the
1523 -- subprogram will get frozen too late (there may be code within
1524 -- the body that depends on the subprogram having been frozen,
1525 -- such as uses of extra formals), so we force it to be frozen
1526 -- here. Same holds if the body and the spec are compilation
1527 -- units.
1529 if No (Spec_Id) then
1530 Freeze_Before (N, Body_Id);
1532 elsif Nkind (Parent (N)) = N_Compilation_Unit then
1533 Freeze_Before (N, Spec_Id);
1534 end if;
1535 else
1536 Spec_Id := Corresponding_Spec (N);
1537 end if;
1538 end if;
1540 -- Do not inline any subprogram that contains nested subprograms, since
1541 -- the backend inlining circuit seems to generate uninitialized
1542 -- references in this case. We know this happens in the case of front
1543 -- end ZCX support, but it also appears it can happen in other cases as
1544 -- well. The backend often rejects attempts to inline in the case of
1545 -- nested procedures anyway, so little if anything is lost by this.
1546 -- Note that this is test is for the benefit of the back-end. There is
1547 -- a separate test for front-end inlining that also rejects nested
1548 -- subprograms.
1550 -- Do not do this test if errors have been detected, because in some
1551 -- error cases, this code blows up, and we don't need it anyway if
1552 -- there have been errors, since we won't get to the linker anyway.
1554 if Comes_From_Source (Body_Id)
1555 and then Serious_Errors_Detected = 0
1556 then
1557 P_Ent := Body_Id;
1558 loop
1559 P_Ent := Scope (P_Ent);
1560 exit when No (P_Ent) or else P_Ent = Standard_Standard;
1562 if Is_Subprogram (P_Ent) then
1563 Set_Is_Inlined (P_Ent, False);
1565 if Comes_From_Source (P_Ent)
1566 and then Has_Pragma_Inline (P_Ent)
1567 then
1568 Cannot_Inline
1569 ("cannot inline& (nested subprogram)?",
1570 N, P_Ent);
1571 end if;
1572 end if;
1573 end loop;
1574 end if;
1576 Check_Inline_Pragma (Spec_Id);
1578 -- Case of fully private operation in the body of the protected type.
1579 -- We must create a declaration for the subprogram, in order to attach
1580 -- the protected subprogram that will be used in internal calls.
1582 if No (Spec_Id)
1583 and then Comes_From_Source (N)
1584 and then Is_Protected_Type (Current_Scope)
1585 then
1586 declare
1587 Decl : Node_Id;
1588 Plist : List_Id;
1589 Formal : Entity_Id;
1590 New_Spec : Node_Id;
1592 begin
1593 Formal := First_Formal (Body_Id);
1595 -- The protected operation always has at least one formal, namely
1596 -- the object itself, but it is only placed in the parameter list
1597 -- if expansion is enabled.
1599 if Present (Formal)
1600 or else Expander_Active
1601 then
1602 Plist := New_List;
1604 else
1605 Plist := No_List;
1606 end if;
1608 Copy_Parameter_List (Plist);
1610 if Nkind (Body_Spec) = N_Procedure_Specification then
1611 New_Spec :=
1612 Make_Procedure_Specification (Loc,
1613 Defining_Unit_Name =>
1614 Make_Defining_Identifier (Sloc (Body_Id),
1615 Chars => Chars (Body_Id)),
1616 Parameter_Specifications => Plist);
1617 else
1618 New_Spec :=
1619 Make_Function_Specification (Loc,
1620 Defining_Unit_Name =>
1621 Make_Defining_Identifier (Sloc (Body_Id),
1622 Chars => Chars (Body_Id)),
1623 Parameter_Specifications => Plist,
1624 Result_Definition =>
1625 New_Occurrence_Of (Etype (Body_Id), Loc));
1626 end if;
1628 Decl :=
1629 Make_Subprogram_Declaration (Loc,
1630 Specification => New_Spec);
1631 Insert_Before (N, Decl);
1632 Spec_Id := Defining_Unit_Name (New_Spec);
1634 -- Indicate that the entity comes from source, to ensure that
1635 -- cross-reference information is properly generated. The body
1636 -- itself is rewritten during expansion, and the body entity will
1637 -- not appear in calls to the operation.
1639 Set_Comes_From_Source (Spec_Id, True);
1640 Analyze (Decl);
1641 Set_Has_Completion (Spec_Id);
1642 Set_Convention (Spec_Id, Convention_Protected);
1643 end;
1645 elsif Present (Spec_Id) then
1646 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1647 Verify_Overriding_Indicator;
1649 -- In general, the spec will be frozen when we start analyzing the
1650 -- body. However, for internally generated operations, such as
1651 -- wrapper functions for inherited operations with controlling
1652 -- results, the spec may not have been frozen by the time we
1653 -- expand the freeze actions that include the bodies. In particular,
1654 -- extra formals for accessibility or for return-in-place may need
1655 -- to be generated. Freeze nodes, if any, are inserted before the
1656 -- current body.
1658 if not Is_Frozen (Spec_Id)
1659 and then Expander_Active
1660 then
1661 -- Force the generation of its freezing node to ensure proper
1662 -- management of access types in the backend.
1664 -- This is definitely needed for some cases, but it is not clear
1665 -- why, to be investigated further???
1667 Set_Has_Delayed_Freeze (Spec_Id);
1668 Insert_Actions (N, Freeze_Entity (Spec_Id, Loc));
1669 end if;
1670 end if;
1672 -- Place subprogram on scope stack, and make formals visible. If there
1673 -- is a spec, the visible entity remains that of the spec.
1675 if Present (Spec_Id) then
1676 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1678 if Is_Child_Unit (Spec_Id) then
1679 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
1680 end if;
1682 if Style_Check then
1683 Style.Check_Identifier (Body_Id, Spec_Id);
1684 end if;
1686 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1687 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1689 if Is_Abstract_Subprogram (Spec_Id) then
1690 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1691 return;
1692 else
1693 Set_Convention (Body_Id, Convention (Spec_Id));
1694 Set_Has_Completion (Spec_Id);
1696 if Is_Protected_Type (Scope (Spec_Id)) then
1697 Set_Privals_Chain (Spec_Id, New_Elmt_List);
1698 end if;
1700 -- If this is a body generated for a renaming, do not check for
1701 -- full conformance. The check is redundant, because the spec of
1702 -- the body is a copy of the spec in the renaming declaration,
1703 -- and the test can lead to spurious errors on nested defaults.
1705 if Present (Spec_Decl)
1706 and then not Comes_From_Source (N)
1707 and then
1708 (Nkind (Original_Node (Spec_Decl)) =
1709 N_Subprogram_Renaming_Declaration
1710 or else (Present (Corresponding_Body (Spec_Decl))
1711 and then
1712 Nkind (Unit_Declaration_Node
1713 (Corresponding_Body (Spec_Decl))) =
1714 N_Subprogram_Renaming_Declaration))
1715 then
1716 Conformant := True;
1717 else
1718 Check_Conformance
1719 (Body_Id, Spec_Id,
1720 Fully_Conformant, True, Conformant, Body_Id);
1721 end if;
1723 -- If the body is not fully conformant, we have to decide if we
1724 -- should analyze it or not. If it has a really messed up profile
1725 -- then we probably should not analyze it, since we will get too
1726 -- many bogus messages.
1728 -- Our decision is to go ahead in the non-fully conformant case
1729 -- only if it is at least mode conformant with the spec. Note
1730 -- that the call to Check_Fully_Conformant has issued the proper
1731 -- error messages to complain about the lack of conformance.
1733 if not Conformant
1734 and then not Mode_Conformant (Body_Id, Spec_Id)
1735 then
1736 return;
1737 end if;
1738 end if;
1740 if Spec_Id /= Body_Id then
1741 Reference_Body_Formals (Spec_Id, Body_Id);
1742 end if;
1744 if Nkind (N) /= N_Subprogram_Body_Stub then
1745 Set_Corresponding_Spec (N, Spec_Id);
1747 -- Ada 2005 (AI-345): If the operation is a primitive operation
1748 -- of a concurrent type, the type of the first parameter has been
1749 -- replaced with the corresponding record, which is the proper
1750 -- run-time structure to use. However, within the body there may
1751 -- be uses of the formals that depend on primitive operations
1752 -- of the type (in particular calls in prefixed form) for which
1753 -- we need the original concurrent type. The operation may have
1754 -- several controlling formals, so the replacement must be done
1755 -- for all of them.
1757 if Comes_From_Source (Spec_Id)
1758 and then Present (First_Entity (Spec_Id))
1759 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
1760 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
1761 and then
1762 Present (Abstract_Interfaces (Etype (First_Entity (Spec_Id))))
1763 and then
1764 Present
1765 (Corresponding_Concurrent_Type
1766 (Etype (First_Entity (Spec_Id))))
1767 then
1768 declare
1769 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
1770 Form : Entity_Id;
1772 begin
1773 Form := First_Formal (Spec_Id);
1774 while Present (Form) loop
1775 if Etype (Form) = Typ then
1776 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
1777 end if;
1779 Next_Formal (Form);
1780 end loop;
1781 end;
1782 end if;
1784 -- Now make the formals visible, and place subprogram
1785 -- on scope stack.
1787 Install_Formals (Spec_Id);
1788 Last_Formal := Last_Entity (Spec_Id);
1789 Push_Scope (Spec_Id);
1791 -- Make sure that the subprogram is immediately visible. For
1792 -- child units that have no separate spec this is indispensable.
1793 -- Otherwise it is safe albeit redundant.
1795 Set_Is_Immediately_Visible (Spec_Id);
1796 end if;
1798 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
1799 Set_Ekind (Body_Id, E_Subprogram_Body);
1800 Set_Scope (Body_Id, Scope (Spec_Id));
1801 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
1803 -- Case of subprogram body with no previous spec
1805 else
1806 if Style_Check
1807 and then Comes_From_Source (Body_Id)
1808 and then not Suppress_Style_Checks (Body_Id)
1809 and then not In_Instance
1810 then
1811 Style.Body_With_No_Spec (N);
1812 end if;
1814 New_Overloaded_Entity (Body_Id);
1816 if Nkind (N) /= N_Subprogram_Body_Stub then
1817 Set_Acts_As_Spec (N);
1818 Generate_Definition (Body_Id);
1819 Generate_Reference
1820 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
1821 Generate_Reference_To_Formals (Body_Id);
1822 Install_Formals (Body_Id);
1823 Push_Scope (Body_Id);
1824 end if;
1825 end if;
1827 -- Ada 2005 (AI-251): Check wrong placement of abstract interface
1828 -- primitives, and update anonymous access returns with limited views.
1830 if Ada_Version >= Ada_05
1831 and then Comes_From_Source (N)
1832 then
1833 declare
1834 E : Entity_Id;
1835 Etyp : Entity_Id;
1836 Rtyp : Entity_Id;
1838 begin
1839 -- Check the type of the formals
1841 E := First_Entity (Body_Id);
1842 while Present (E) loop
1843 Etyp := Etype (E);
1845 if Is_Access_Type (Etyp) then
1846 Etyp := Directly_Designated_Type (Etyp);
1847 end if;
1849 if not Is_Class_Wide_Type (Etyp)
1850 and then Is_Interface (Etyp)
1851 then
1852 Error_Msg_Name_1 := Chars (Defining_Entity (N));
1853 Error_Msg_N
1854 ("(Ada 2005) abstract interface primitives must be" &
1855 " defined in package specs", N);
1856 exit;
1857 end if;
1859 Next_Entity (E);
1860 end loop;
1862 -- In case of functions, check the type of the result
1864 if Ekind (Body_Id) = E_Function then
1865 Etyp := Etype (Body_Id);
1867 if Is_Access_Type (Etyp) then
1868 Etyp := Directly_Designated_Type (Etyp);
1869 end if;
1871 if not Is_Class_Wide_Type (Etyp)
1872 and then Is_Interface (Etyp)
1873 then
1874 Error_Msg_Name_1 := Chars (Defining_Entity (N));
1875 Error_Msg_N
1876 ("(Ada 2005) abstract interface primitives must be" &
1877 " defined in package specs", N);
1878 end if;
1879 end if;
1881 -- If the return type is an anonymous access type whose
1882 -- designated type is the limited view of a class-wide type
1883 -- and the non-limited view is available. update the return
1884 -- type accordingly.
1886 Rtyp := Etype (Current_Scope);
1888 if Ekind (Rtyp) = E_Anonymous_Access_Type then
1889 Etyp := Directly_Designated_Type (Rtyp);
1891 if Is_Class_Wide_Type (Etyp)
1892 and then From_With_Type (Etyp)
1893 then
1894 Set_Directly_Designated_Type
1895 (Etype (Current_Scope), Available_View (Etyp));
1896 end if;
1897 end if;
1898 end;
1899 end if;
1901 -- If this is the proper body of a stub, we must verify that the stub
1902 -- conforms to the body, and to the previous spec if one was present.
1903 -- we know already that the body conforms to that spec. This test is
1904 -- only required for subprograms that come from source.
1906 if Nkind (Parent (N)) = N_Subunit
1907 and then Comes_From_Source (N)
1908 and then not Error_Posted (Body_Id)
1909 and then Nkind (Corresponding_Stub (Parent (N))) =
1910 N_Subprogram_Body_Stub
1911 then
1912 declare
1913 Old_Id : constant Entity_Id :=
1914 Defining_Entity
1915 (Specification (Corresponding_Stub (Parent (N))));
1917 Conformant : Boolean := False;
1919 begin
1920 if No (Spec_Id) then
1921 Check_Fully_Conformant (Body_Id, Old_Id);
1923 else
1924 Check_Conformance
1925 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
1927 if not Conformant then
1929 -- The stub was taken to be a new declaration. Indicate
1930 -- that it lacks a body.
1932 Set_Has_Completion (Old_Id, False);
1933 end if;
1934 end if;
1935 end;
1936 end if;
1938 Set_Has_Completion (Body_Id);
1939 Check_Eliminated (Body_Id);
1941 if Nkind (N) = N_Subprogram_Body_Stub then
1942 return;
1944 elsif Present (Spec_Id)
1945 and then Expander_Active
1946 and then
1947 (Is_Always_Inlined (Spec_Id)
1948 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
1949 then
1950 Build_Body_To_Inline (N, Spec_Id);
1951 end if;
1953 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
1954 -- if its specification we have to install the private withed units.
1956 if Is_Compilation_Unit (Body_Id)
1957 and then Scope (Body_Id) = Standard_Standard
1958 then
1959 Install_Private_With_Clauses (Body_Id);
1960 end if;
1962 Check_Anonymous_Return;
1964 -- Set the Protected_Formal field of each extra formal of the protected
1965 -- subprogram to reference the corresponding extra formal of the
1966 -- subprogram that implements it. For regular formals this occurs when
1967 -- the protected subprogram's declaration is expanded, but the extra
1968 -- formals don't get created until the subprogram is frozen. We need to
1969 -- do this before analyzing the protected subprogram's body so that any
1970 -- references to the original subprogram's extra formals will be changed
1971 -- refer to the implementing subprogram's formals (see Expand_Formal).
1973 if Present (Spec_Id)
1974 and then Is_Protected_Type (Scope (Spec_Id))
1975 and then Present (Protected_Body_Subprogram (Spec_Id))
1976 then
1977 declare
1978 Impl_Subp : constant Entity_Id :=
1979 Protected_Body_Subprogram (Spec_Id);
1980 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
1981 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
1983 begin
1984 while Present (Prot_Ext_Formal) loop
1985 pragma Assert (Present (Impl_Ext_Formal));
1987 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
1989 Next_Formal_With_Extras (Prot_Ext_Formal);
1990 Next_Formal_With_Extras (Impl_Ext_Formal);
1991 end loop;
1992 end;
1993 end if;
1995 -- Now we can go on to analyze the body
1997 HSS := Handled_Statement_Sequence (N);
1998 Set_Actual_Subtypes (N, Current_Scope);
1999 Analyze_Declarations (Declarations (N));
2000 Check_Completion;
2001 Analyze (HSS);
2002 Process_End_Label (HSS, 't', Current_Scope);
2003 End_Scope;
2004 Check_Subprogram_Order (N);
2005 Set_Analyzed (Body_Id);
2007 -- If we have a separate spec, then the analysis of the declarations
2008 -- caused the entities in the body to be chained to the spec id, but
2009 -- we want them chained to the body id. Only the formal parameters
2010 -- end up chained to the spec id in this case.
2012 if Present (Spec_Id) then
2014 -- We must conform to the categorization of our spec
2016 Validate_Categorization_Dependency (N, Spec_Id);
2018 -- And if this is a child unit, the parent units must conform
2020 if Is_Child_Unit (Spec_Id) then
2021 Validate_Categorization_Dependency
2022 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2023 end if;
2025 if Present (Last_Formal) then
2026 Set_Next_Entity
2027 (Last_Entity (Body_Id), Next_Entity (Last_Formal));
2028 Set_Next_Entity (Last_Formal, Empty);
2029 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2030 Set_Last_Entity (Spec_Id, Last_Formal);
2032 else
2033 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2034 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2035 Set_First_Entity (Spec_Id, Empty);
2036 Set_Last_Entity (Spec_Id, Empty);
2037 end if;
2038 end if;
2040 -- If function, check return statements
2042 if Nkind (Body_Spec) = N_Function_Specification then
2043 declare
2044 Id : Entity_Id;
2046 begin
2047 if Present (Spec_Id) then
2048 Id := Spec_Id;
2049 else
2050 Id := Body_Id;
2051 end if;
2053 if Return_Present (Id) then
2054 Check_Returns (HSS, 'F', Missing_Ret);
2056 if Missing_Ret then
2057 Set_Has_Missing_Return (Id);
2058 end if;
2060 elsif not Is_Machine_Code_Subprogram (Id)
2061 and then not Body_Deleted
2062 then
2063 Error_Msg_N ("missing RETURN statement in function body", N);
2064 end if;
2065 end;
2067 -- If procedure with No_Return, check returns
2069 elsif Nkind (Body_Spec) = N_Procedure_Specification
2070 and then Present (Spec_Id)
2071 and then No_Return (Spec_Id)
2072 then
2073 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2074 end if;
2076 -- Now we are going to check for variables that are never modified in
2077 -- the body of the procedure. We omit these checks if the first
2078 -- statement of the procedure raises an exception. In particular this
2079 -- deals with the common idiom of a stubbed function, which might
2080 -- appear as something like
2082 -- function F (A : Integer) return Some_Type;
2083 -- X : Some_Type;
2084 -- begin
2085 -- raise Program_Error;
2086 -- return X;
2087 -- end F;
2089 -- Here the purpose of X is simply to satisfy the (annoying)
2090 -- requirement in Ada that there be at least one return, and we
2091 -- certainly do not want to go posting warnings on X that it is not
2092 -- initialized!
2094 declare
2095 Stm : Node_Id := First (Statements (HSS));
2097 begin
2098 -- Skip initial labels (for one thing this occurs when we are in
2099 -- front end ZCX mode, but in any case it is irrelevant), and also
2100 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2102 while Nkind (Stm) = N_Label
2103 or else Nkind (Stm) in N_Push_xxx_Label
2104 loop
2105 Next (Stm);
2106 end loop;
2108 -- Do the test on the original statement before expansion
2110 declare
2111 Ostm : constant Node_Id := Original_Node (Stm);
2113 begin
2114 -- If explicit raise statement, return with no checks
2116 if Nkind (Ostm) = N_Raise_Statement then
2117 return;
2119 -- Check for explicit call cases which likely raise an exception
2121 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2122 if Is_Entity_Name (Name (Ostm)) then
2123 declare
2124 Ent : constant Entity_Id := Entity (Name (Ostm));
2126 begin
2127 -- If the procedure is marked No_Return, then likely it
2128 -- raises an exception, but in any case it is not coming
2129 -- back here, so no need to check beyond the call.
2131 if Ekind (Ent) = E_Procedure
2132 and then No_Return (Ent)
2133 then
2134 return;
2136 -- If the procedure name is Raise_Exception, then also
2137 -- assume that it raises an exception. The main target
2138 -- here is Ada.Exceptions.Raise_Exception, but this name
2139 -- is pretty evocative in any context! Note that the
2140 -- procedure in Ada.Exceptions is not marked No_Return
2141 -- because of the annoying case of the null exception Id.
2143 elsif Chars (Ent) = Name_Raise_Exception then
2144 return;
2145 end if;
2146 end;
2147 end if;
2148 end if;
2149 end;
2150 end;
2152 -- Check for variables that are never modified
2154 declare
2155 E1, E2 : Entity_Id;
2157 begin
2158 -- If there is a separate spec, then transfer Never_Set_In_Source
2159 -- flags from out parameters to the corresponding entities in the
2160 -- body. The reason we do that is we want to post error flags on
2161 -- the body entities, not the spec entities.
2163 if Present (Spec_Id) then
2164 E1 := First_Entity (Spec_Id);
2165 while Present (E1) loop
2166 if Ekind (E1) = E_Out_Parameter then
2167 E2 := First_Entity (Body_Id);
2168 while Present (E2) loop
2169 exit when Chars (E1) = Chars (E2);
2170 Next_Entity (E2);
2171 end loop;
2173 if Present (E2) then
2174 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2175 end if;
2176 end if;
2178 Next_Entity (E1);
2179 end loop;
2180 end if;
2182 -- Check references in body unless it was deleted. Note that the
2183 -- check of Body_Deleted here is not just for efficiency, it is
2184 -- necessary to avoid junk warnings on formal parameters.
2186 if not Body_Deleted then
2187 Check_References (Body_Id);
2188 end if;
2189 end;
2190 end Analyze_Subprogram_Body;
2192 ------------------------------------
2193 -- Analyze_Subprogram_Declaration --
2194 ------------------------------------
2196 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2197 Designator : constant Entity_Id :=
2198 Analyze_Subprogram_Specification (Specification (N));
2199 Scop : constant Entity_Id := Current_Scope;
2201 -- Start of processing for Analyze_Subprogram_Declaration
2203 begin
2204 Generate_Definition (Designator);
2206 -- Check for RCI unit subprogram declarations for illegal inlined
2207 -- subprograms and subprograms having access parameter or limited
2208 -- parameter without Read and Write attributes (RM E.2.3(12-13)).
2210 Validate_RCI_Subprogram_Declaration (N);
2212 Trace_Scope
2214 Defining_Entity (N),
2215 " Analyze subprogram spec. ");
2217 if Debug_Flag_C then
2218 Write_Str ("==== Compiling subprogram spec ");
2219 Write_Name (Chars (Designator));
2220 Write_Str (" from ");
2221 Write_Location (Sloc (N));
2222 Write_Eol;
2223 end if;
2225 New_Overloaded_Entity (Designator);
2226 Check_Delayed_Subprogram (Designator);
2228 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
2229 -- or null.
2231 if Ada_Version >= Ada_05
2232 and then Comes_From_Source (N)
2233 and then Is_Dispatching_Operation (Designator)
2234 then
2235 declare
2236 E : Entity_Id;
2237 Etyp : Entity_Id;
2239 begin
2240 if Has_Controlling_Result (Designator) then
2241 Etyp := Etype (Designator);
2243 else
2244 E := First_Entity (Designator);
2245 while Present (E)
2246 and then Is_Formal (E)
2247 and then not Is_Controlling_Formal (E)
2248 loop
2249 Next_Entity (E);
2250 end loop;
2252 Etyp := Etype (E);
2253 end if;
2255 if Is_Access_Type (Etyp) then
2256 Etyp := Directly_Designated_Type (Etyp);
2257 end if;
2259 if Is_Interface (Etyp)
2260 and then not Is_Abstract_Subprogram (Designator)
2261 and then not (Ekind (Designator) = E_Procedure
2262 and then Null_Present (Specification (N)))
2263 then
2264 Error_Msg_Name_1 := Chars (Defining_Entity (N));
2265 Error_Msg_N
2266 ("(Ada 2005) interface subprogram % must be abstract or null",
2268 end if;
2269 end;
2270 end if;
2272 -- What is the following code for, it used to be
2274 -- ??? Set_Suppress_Elaboration_Checks
2275 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
2277 -- The following seems equivalent, but a bit dubious
2279 if Elaboration_Checks_Suppressed (Designator) then
2280 Set_Kill_Elaboration_Checks (Designator);
2281 end if;
2283 if Scop /= Standard_Standard
2284 and then not Is_Child_Unit (Designator)
2285 then
2286 Set_Categorization_From_Scope (Designator, Scop);
2287 else
2288 -- For a compilation unit, check for library-unit pragmas
2290 Push_Scope (Designator);
2291 Set_Categorization_From_Pragmas (N);
2292 Validate_Categorization_Dependency (N, Designator);
2293 Pop_Scope;
2294 end if;
2296 -- For a compilation unit, set body required. This flag will only be
2297 -- reset if a valid Import or Interface pragma is processed later on.
2299 if Nkind (Parent (N)) = N_Compilation_Unit then
2300 Set_Body_Required (Parent (N), True);
2302 if Ada_Version >= Ada_05
2303 and then Nkind (Specification (N)) = N_Procedure_Specification
2304 and then Null_Present (Specification (N))
2305 then
2306 Error_Msg_N
2307 ("null procedure cannot be declared at library level", N);
2308 end if;
2309 end if;
2311 Generate_Reference_To_Formals (Designator);
2312 Check_Eliminated (Designator);
2314 -- Ada 2005: if procedure is declared with "is null" qualifier,
2315 -- it requires no body.
2317 if Nkind (Specification (N)) = N_Procedure_Specification
2318 and then Null_Present (Specification (N))
2319 then
2320 Set_Has_Completion (Designator);
2321 Set_Is_Inlined (Designator);
2323 if Is_Protected_Type (Current_Scope) then
2324 Error_Msg_N
2325 ("protected operation cannot be a null procedure", N);
2326 end if;
2327 end if;
2328 end Analyze_Subprogram_Declaration;
2330 --------------------------------------
2331 -- Analyze_Subprogram_Specification --
2332 --------------------------------------
2334 -- Reminder: N here really is a subprogram specification (not a subprogram
2335 -- declaration). This procedure is called to analyze the specification in
2336 -- both subprogram bodies and subprogram declarations (specs).
2338 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
2339 Designator : constant Entity_Id := Defining_Entity (N);
2340 Formal : Entity_Id;
2341 Formal_Typ : Entity_Id;
2342 Formals : constant List_Id := Parameter_Specifications (N);
2344 -- Start of processing for Analyze_Subprogram_Specification
2346 begin
2347 Generate_Definition (Designator);
2349 if Nkind (N) = N_Function_Specification then
2350 Set_Ekind (Designator, E_Function);
2351 Set_Mechanism (Designator, Default_Mechanism);
2353 else
2354 Set_Ekind (Designator, E_Procedure);
2355 Set_Etype (Designator, Standard_Void_Type);
2356 end if;
2358 -- Introduce new scope for analysis of the formals and of the
2359 -- return type.
2361 Set_Scope (Designator, Current_Scope);
2363 if Present (Formals) then
2364 Push_Scope (Designator);
2365 Process_Formals (Formals, N);
2367 -- Ada 2005 (AI-345): Allow the overriding of interface primitives
2368 -- by subprograms which belong to a concurrent type implementing an
2369 -- interface. Set the parameter type of each controlling formal to
2370 -- the corresponding record type.
2372 if Ada_Version >= Ada_05 then
2373 Formal := First_Formal (Designator);
2374 while Present (Formal) loop
2375 Formal_Typ := Etype (Formal);
2377 if (Ekind (Formal_Typ) = E_Protected_Type
2378 or else Ekind (Formal_Typ) = E_Task_Type)
2379 and then Present (Corresponding_Record_Type (Formal_Typ))
2380 and then Present (Abstract_Interfaces
2381 (Corresponding_Record_Type (Formal_Typ)))
2382 then
2383 Set_Etype (Formal,
2384 Corresponding_Record_Type (Formal_Typ));
2385 end if;
2387 Formal := Next_Formal (Formal);
2388 end loop;
2389 end if;
2391 End_Scope;
2393 elsif Nkind (N) = N_Function_Specification then
2394 Analyze_Return_Type (N);
2395 end if;
2397 if Nkind (N) = N_Function_Specification then
2398 if Nkind (Designator) = N_Defining_Operator_Symbol then
2399 Valid_Operator_Definition (Designator);
2400 end if;
2402 May_Need_Actuals (Designator);
2404 -- Ada 2005 (AI-251): In case of primitives associated with abstract
2405 -- interface types the following error message will be reported later
2406 -- (see Analyze_Subprogram_Declaration).
2408 if Is_Abstract_Type (Etype (Designator))
2409 and then not Is_Interface (Etype (Designator))
2410 and then Nkind (Parent (N))
2411 /= N_Abstract_Subprogram_Declaration
2412 and then (Nkind (Parent (N)))
2413 /= N_Formal_Abstract_Subprogram_Declaration
2414 and then (Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
2415 or else not Is_Entity_Name (Name (Parent (N)))
2416 or else not Is_Abstract_Subprogram
2417 (Entity (Name (Parent (N)))))
2418 then
2419 Error_Msg_N
2420 ("function that returns abstract type must be abstract", N);
2421 end if;
2422 end if;
2424 return Designator;
2425 end Analyze_Subprogram_Specification;
2427 --------------------------
2428 -- Build_Body_To_Inline --
2429 --------------------------
2431 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
2432 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
2433 Original_Body : Node_Id;
2434 Body_To_Analyze : Node_Id;
2435 Max_Size : constant := 10;
2436 Stat_Count : Integer := 0;
2438 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
2439 -- Check for declarations that make inlining not worthwhile
2441 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
2442 -- Check for statements that make inlining not worthwhile: any tasking
2443 -- statement, nested at any level. Keep track of total number of
2444 -- elementary statements, as a measure of acceptable size.
2446 function Has_Pending_Instantiation return Boolean;
2447 -- If some enclosing body contains instantiations that appear before the
2448 -- corresponding generic body, the enclosing body has a freeze node so
2449 -- that it can be elaborated after the generic itself. This might
2450 -- conflict with subsequent inlinings, so that it is unsafe to try to
2451 -- inline in such a case.
2453 function Has_Single_Return return Boolean;
2454 -- In general we cannot inline functions that return unconstrained type.
2455 -- However, we can handle such functions if all return statements return
2456 -- a local variable that is the only declaration in the body of the
2457 -- function. In that case the call can be replaced by that local
2458 -- variable as is done for other inlined calls.
2460 procedure Remove_Pragmas;
2461 -- A pragma Unreferenced that mentions a formal parameter has no meaning
2462 -- when the body is inlined and the formals are rewritten. Remove it
2463 -- from body to inline. The analysis of the non-inlined body will handle
2464 -- the pragma properly.
2466 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
2467 -- If the body of the subprogram includes a call that returns an
2468 -- unconstrained type, the secondary stack is involved, and it
2469 -- is not worth inlining.
2471 ------------------------------
2472 -- Has_Excluded_Declaration --
2473 ------------------------------
2475 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
2476 D : Node_Id;
2478 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
2479 -- Nested subprograms make a given body ineligible for inlining, but
2480 -- we make an exception for instantiations of unchecked conversion.
2481 -- The body has not been analyzed yet, so check the name, and verify
2482 -- that the visible entity with that name is the predefined unit.
2484 -----------------------------
2485 -- Is_Unchecked_Conversion --
2486 -----------------------------
2488 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
2489 Id : constant Node_Id := Name (D);
2490 Conv : Entity_Id;
2492 begin
2493 if Nkind (Id) = N_Identifier
2494 and then Chars (Id) = Name_Unchecked_Conversion
2495 then
2496 Conv := Current_Entity (Id);
2498 elsif (Nkind (Id) = N_Selected_Component
2499 or else Nkind (Id) = N_Expanded_Name)
2500 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
2501 then
2502 Conv := Current_Entity (Selector_Name (Id));
2504 else
2505 return False;
2506 end if;
2508 return Present (Conv)
2509 and then Is_Predefined_File_Name
2510 (Unit_File_Name (Get_Source_Unit (Conv)))
2511 and then Is_Intrinsic_Subprogram (Conv);
2512 end Is_Unchecked_Conversion;
2514 -- Start of processing for Has_Excluded_Declaration
2516 begin
2517 D := First (Decls);
2519 while Present (D) loop
2520 if (Nkind (D) = N_Function_Instantiation
2521 and then not Is_Unchecked_Conversion (D))
2522 or else Nkind (D) = N_Protected_Type_Declaration
2523 or else Nkind (D) = N_Package_Declaration
2524 or else Nkind (D) = N_Package_Instantiation
2525 or else Nkind (D) = N_Subprogram_Body
2526 or else Nkind (D) = N_Procedure_Instantiation
2527 or else Nkind (D) = N_Task_Type_Declaration
2528 then
2529 Cannot_Inline
2530 ("cannot inline & (non-allowed declaration)?", D, Subp);
2531 return True;
2532 end if;
2534 Next (D);
2535 end loop;
2537 return False;
2538 end Has_Excluded_Declaration;
2540 ----------------------------
2541 -- Has_Excluded_Statement --
2542 ----------------------------
2544 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
2545 S : Node_Id;
2546 E : Node_Id;
2548 begin
2549 S := First (Stats);
2550 while Present (S) loop
2551 Stat_Count := Stat_Count + 1;
2553 if Nkind (S) = N_Abort_Statement
2554 or else Nkind (S) = N_Asynchronous_Select
2555 or else Nkind (S) = N_Conditional_Entry_Call
2556 or else Nkind (S) = N_Delay_Relative_Statement
2557 or else Nkind (S) = N_Delay_Until_Statement
2558 or else Nkind (S) = N_Selective_Accept
2559 or else Nkind (S) = N_Timed_Entry_Call
2560 then
2561 Cannot_Inline
2562 ("cannot inline & (non-allowed statement)?", S, Subp);
2563 return True;
2565 elsif Nkind (S) = N_Block_Statement then
2566 if Present (Declarations (S))
2567 and then Has_Excluded_Declaration (Declarations (S))
2568 then
2569 return True;
2571 elsif Present (Handled_Statement_Sequence (S))
2572 and then
2573 (Present
2574 (Exception_Handlers (Handled_Statement_Sequence (S)))
2575 or else
2576 Has_Excluded_Statement
2577 (Statements (Handled_Statement_Sequence (S))))
2578 then
2579 return True;
2580 end if;
2582 elsif Nkind (S) = N_Case_Statement then
2583 E := First (Alternatives (S));
2584 while Present (E) loop
2585 if Has_Excluded_Statement (Statements (E)) then
2586 return True;
2587 end if;
2589 Next (E);
2590 end loop;
2592 elsif Nkind (S) = N_If_Statement then
2593 if Has_Excluded_Statement (Then_Statements (S)) then
2594 return True;
2595 end if;
2597 if Present (Elsif_Parts (S)) then
2598 E := First (Elsif_Parts (S));
2599 while Present (E) loop
2600 if Has_Excluded_Statement (Then_Statements (E)) then
2601 return True;
2602 end if;
2603 Next (E);
2604 end loop;
2605 end if;
2607 if Present (Else_Statements (S))
2608 and then Has_Excluded_Statement (Else_Statements (S))
2609 then
2610 return True;
2611 end if;
2613 elsif Nkind (S) = N_Loop_Statement
2614 and then Has_Excluded_Statement (Statements (S))
2615 then
2616 return True;
2617 end if;
2619 Next (S);
2620 end loop;
2622 return False;
2623 end Has_Excluded_Statement;
2625 -------------------------------
2626 -- Has_Pending_Instantiation --
2627 -------------------------------
2629 function Has_Pending_Instantiation return Boolean is
2630 S : Entity_Id;
2632 begin
2633 S := Current_Scope;
2634 while Present (S) loop
2635 if Is_Compilation_Unit (S)
2636 or else Is_Child_Unit (S)
2637 then
2638 return False;
2639 elsif Ekind (S) = E_Package
2640 and then Has_Forward_Instantiation (S)
2641 then
2642 return True;
2643 end if;
2645 S := Scope (S);
2646 end loop;
2648 return False;
2649 end Has_Pending_Instantiation;
2651 ------------------------
2652 -- Has_Single_Return --
2653 ------------------------
2655 function Has_Single_Return return Boolean is
2656 Return_Statement : Node_Id := Empty;
2658 function Check_Return (N : Node_Id) return Traverse_Result;
2660 ------------------
2661 -- Check_Return --
2662 ------------------
2664 function Check_Return (N : Node_Id) return Traverse_Result is
2665 begin
2666 if Nkind (N) = N_Simple_Return_Statement then
2667 if Present (Expression (N))
2668 and then Is_Entity_Name (Expression (N))
2669 then
2670 if No (Return_Statement) then
2671 Return_Statement := N;
2672 return OK;
2674 elsif Chars (Expression (N)) =
2675 Chars (Expression (Return_Statement))
2676 then
2677 return OK;
2679 else
2680 return Abandon;
2681 end if;
2683 else
2684 -- Expression has wrong form
2686 return Abandon;
2687 end if;
2689 else
2690 return OK;
2691 end if;
2692 end Check_Return;
2694 function Check_All_Returns is new Traverse_Func (Check_Return);
2696 -- Start of processing for Has_Single_Return
2698 begin
2699 return Check_All_Returns (N) = OK
2700 and then Present (Declarations (N))
2701 and then Present (First (Declarations (N)))
2702 and then Chars (Expression (Return_Statement)) =
2703 Chars (Defining_Identifier (First (Declarations (N))));
2704 end Has_Single_Return;
2706 --------------------
2707 -- Remove_Pragmas --
2708 --------------------
2710 procedure Remove_Pragmas is
2711 Decl : Node_Id;
2712 Nxt : Node_Id;
2714 begin
2715 Decl := First (Declarations (Body_To_Analyze));
2716 while Present (Decl) loop
2717 Nxt := Next (Decl);
2719 if Nkind (Decl) = N_Pragma
2720 and then Chars (Decl) = Name_Unreferenced
2721 then
2722 Remove (Decl);
2723 end if;
2725 Decl := Nxt;
2726 end loop;
2727 end Remove_Pragmas;
2729 --------------------------
2730 -- Uses_Secondary_Stack --
2731 --------------------------
2733 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
2734 function Check_Call (N : Node_Id) return Traverse_Result;
2735 -- Look for function calls that return an unconstrained type
2737 ----------------
2738 -- Check_Call --
2739 ----------------
2741 function Check_Call (N : Node_Id) return Traverse_Result is
2742 begin
2743 if Nkind (N) = N_Function_Call
2744 and then Is_Entity_Name (Name (N))
2745 and then Is_Composite_Type (Etype (Entity (Name (N))))
2746 and then not Is_Constrained (Etype (Entity (Name (N))))
2747 then
2748 Cannot_Inline
2749 ("cannot inline & (call returns unconstrained type)?",
2750 N, Subp);
2751 return Abandon;
2752 else
2753 return OK;
2754 end if;
2755 end Check_Call;
2757 function Check_Calls is new Traverse_Func (Check_Call);
2759 begin
2760 return Check_Calls (Bod) = Abandon;
2761 end Uses_Secondary_Stack;
2763 -- Start of processing for Build_Body_To_Inline
2765 begin
2766 if Nkind (Decl) = N_Subprogram_Declaration
2767 and then Present (Body_To_Inline (Decl))
2768 then
2769 return; -- Done already.
2771 -- Functions that return unconstrained composite types require
2772 -- secondary stack handling, and cannot currently be inlined, unless
2773 -- all return statements return a local variable that is the first
2774 -- local declaration in the body.
2776 elsif Ekind (Subp) = E_Function
2777 and then not Is_Scalar_Type (Etype (Subp))
2778 and then not Is_Access_Type (Etype (Subp))
2779 and then not Is_Constrained (Etype (Subp))
2780 then
2781 if not Has_Single_Return then
2782 Cannot_Inline
2783 ("cannot inline & (unconstrained return type)?", N, Subp);
2784 return;
2785 end if;
2787 -- Ditto for functions that return controlled types, where controlled
2788 -- actions interfere in complex ways with inlining.
2790 elsif Ekind (Subp) = E_Function
2791 and then Controlled_Type (Etype (Subp))
2792 then
2793 Cannot_Inline
2794 ("cannot inline & (controlled return type)?", N, Subp);
2795 return;
2796 end if;
2798 if Present (Declarations (N))
2799 and then Has_Excluded_Declaration (Declarations (N))
2800 then
2801 return;
2802 end if;
2804 if Present (Handled_Statement_Sequence (N)) then
2805 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
2806 Cannot_Inline
2807 ("cannot inline& (exception handler)?",
2808 First (Exception_Handlers (Handled_Statement_Sequence (N))),
2809 Subp);
2810 return;
2811 elsif
2812 Has_Excluded_Statement
2813 (Statements (Handled_Statement_Sequence (N)))
2814 then
2815 return;
2816 end if;
2817 end if;
2819 -- We do not inline a subprogram that is too large, unless it is
2820 -- marked Inline_Always. This pragma does not suppress the other
2821 -- checks on inlining (forbidden declarations, handlers, etc).
2823 if Stat_Count > Max_Size
2824 and then not Is_Always_Inlined (Subp)
2825 then
2826 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
2827 return;
2828 end if;
2830 if Has_Pending_Instantiation then
2831 Cannot_Inline
2832 ("cannot inline& (forward instance within enclosing body)?",
2833 N, Subp);
2834 return;
2835 end if;
2837 -- Within an instance, the body to inline must be treated as a nested
2838 -- generic, so that the proper global references are preserved.
2840 if In_Instance then
2841 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
2842 Original_Body := Copy_Generic_Node (N, Empty, True);
2843 else
2844 Original_Body := Copy_Separate_Tree (N);
2845 end if;
2847 -- We need to capture references to the formals in order to substitute
2848 -- the actuals at the point of inlining, i.e. instantiation. To treat
2849 -- the formals as globals to the body to inline, we nest it within
2850 -- a dummy parameterless subprogram, declared within the real one.
2851 -- To avoid generating an internal name (which is never public, and
2852 -- which affects serial numbers of other generated names), we use
2853 -- an internal symbol that cannot conflict with user declarations.
2855 Set_Parameter_Specifications (Specification (Original_Body), No_List);
2856 Set_Defining_Unit_Name
2857 (Specification (Original_Body),
2858 Make_Defining_Identifier (Sloc (N), Name_uParent));
2859 Set_Corresponding_Spec (Original_Body, Empty);
2861 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
2863 -- Set return type of function, which is also global and does not need
2864 -- to be resolved.
2866 if Ekind (Subp) = E_Function then
2867 Set_Result_Definition (Specification (Body_To_Analyze),
2868 New_Occurrence_Of (Etype (Subp), Sloc (N)));
2869 end if;
2871 if No (Declarations (N)) then
2872 Set_Declarations (N, New_List (Body_To_Analyze));
2873 else
2874 Append (Body_To_Analyze, Declarations (N));
2875 end if;
2877 Expander_Mode_Save_And_Set (False);
2878 Remove_Pragmas;
2880 Analyze (Body_To_Analyze);
2881 Push_Scope (Defining_Entity (Body_To_Analyze));
2882 Save_Global_References (Original_Body);
2883 End_Scope;
2884 Remove (Body_To_Analyze);
2886 Expander_Mode_Restore;
2888 if In_Instance then
2889 Restore_Env;
2890 end if;
2892 -- If secondary stk used there is no point in inlining. We have
2893 -- already issued the warning in this case, so nothing to do.
2895 if Uses_Secondary_Stack (Body_To_Analyze) then
2896 return;
2897 end if;
2899 Set_Body_To_Inline (Decl, Original_Body);
2900 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
2901 Set_Is_Inlined (Subp);
2902 end Build_Body_To_Inline;
2904 -------------------
2905 -- Cannot_Inline --
2906 -------------------
2908 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
2909 begin
2910 -- Do not emit warning if this is a predefined unit which is not
2911 -- the main unit. With validity checks enabled, some predefined
2912 -- subprograms may contain nested subprograms and become ineligible
2913 -- for inlining.
2915 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
2916 and then not In_Extended_Main_Source_Unit (Subp)
2917 then
2918 null;
2920 elsif Is_Always_Inlined (Subp) then
2922 -- Remove last character (question mark) to make this into an error,
2923 -- because the Inline_Always pragma cannot be obeyed.
2925 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
2927 elsif Ineffective_Inline_Warnings then
2928 Error_Msg_NE (Msg, N, Subp);
2929 end if;
2930 end Cannot_Inline;
2932 -----------------------
2933 -- Check_Conformance --
2934 -----------------------
2936 procedure Check_Conformance
2937 (New_Id : Entity_Id;
2938 Old_Id : Entity_Id;
2939 Ctype : Conformance_Type;
2940 Errmsg : Boolean;
2941 Conforms : out Boolean;
2942 Err_Loc : Node_Id := Empty;
2943 Get_Inst : Boolean := False;
2944 Skip_Controlling_Formals : Boolean := False)
2946 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
2947 -- Post error message for conformance error on given node. Two messages
2948 -- are output. The first points to the previous declaration with a
2949 -- general "no conformance" message. The second is the detailed reason,
2950 -- supplied as Msg. The parameter N provide information for a possible
2951 -- & insertion in the message, and also provides the location for
2952 -- posting the message in the absence of a specified Err_Loc location.
2954 -----------------------
2955 -- Conformance_Error --
2956 -----------------------
2958 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
2959 Enode : Node_Id;
2961 begin
2962 Conforms := False;
2964 if Errmsg then
2965 if No (Err_Loc) then
2966 Enode := N;
2967 else
2968 Enode := Err_Loc;
2969 end if;
2971 Error_Msg_Sloc := Sloc (Old_Id);
2973 case Ctype is
2974 when Type_Conformant =>
2975 Error_Msg_N
2976 ("not type conformant with declaration#!", Enode);
2978 when Mode_Conformant =>
2979 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2980 Error_Msg_N
2981 ("not mode conformant with operation inherited#!",
2982 Enode);
2983 else
2984 Error_Msg_N
2985 ("not mode conformant with declaration#!", Enode);
2986 end if;
2988 when Subtype_Conformant =>
2989 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2990 Error_Msg_N
2991 ("not subtype conformant with operation inherited#!",
2992 Enode);
2993 else
2994 Error_Msg_N
2995 ("not subtype conformant with declaration#!", Enode);
2996 end if;
2998 when Fully_Conformant =>
2999 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3000 Error_Msg_N
3001 ("not fully conformant with operation inherited#!",
3002 Enode);
3003 else
3004 Error_Msg_N
3005 ("not fully conformant with declaration#!", Enode);
3006 end if;
3007 end case;
3009 Error_Msg_NE (Msg, Enode, N);
3010 end if;
3011 end Conformance_Error;
3013 -- Local Variables
3015 Old_Type : constant Entity_Id := Etype (Old_Id);
3016 New_Type : constant Entity_Id := Etype (New_Id);
3017 Old_Formal : Entity_Id;
3018 New_Formal : Entity_Id;
3019 Access_Types_Match : Boolean;
3020 Old_Formal_Base : Entity_Id;
3021 New_Formal_Base : Entity_Id;
3023 -- Start of processing for Check_Conformance
3025 begin
3026 Conforms := True;
3028 -- We need a special case for operators, since they don't appear
3029 -- explicitly.
3031 if Ctype = Type_Conformant then
3032 if Ekind (New_Id) = E_Operator
3033 and then Operator_Matches_Spec (New_Id, Old_Id)
3034 then
3035 return;
3036 end if;
3037 end if;
3039 -- If both are functions/operators, check return types conform
3041 if Old_Type /= Standard_Void_Type
3042 and then New_Type /= Standard_Void_Type
3043 then
3044 if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3045 Conformance_Error ("\return type does not match!", New_Id);
3046 return;
3047 end if;
3049 -- Ada 2005 (AI-231): In case of anonymous access types check the
3050 -- null-exclusion and access-to-constant attributes match.
3052 if Ada_Version >= Ada_05
3053 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3054 and then
3055 (Can_Never_Be_Null (Old_Type)
3056 /= Can_Never_Be_Null (New_Type)
3057 or else Is_Access_Constant (Etype (Old_Type))
3058 /= Is_Access_Constant (Etype (New_Type)))
3059 then
3060 Conformance_Error ("\return type does not match!", New_Id);
3061 return;
3062 end if;
3064 -- If either is a function/operator and the other isn't, error
3066 elsif Old_Type /= Standard_Void_Type
3067 or else New_Type /= Standard_Void_Type
3068 then
3069 Conformance_Error ("\functions can only match functions!", New_Id);
3070 return;
3071 end if;
3073 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
3074 -- If this is a renaming as body, refine error message to indicate that
3075 -- the conflict is with the original declaration. If the entity is not
3076 -- frozen, the conventions don't have to match, the one of the renamed
3077 -- entity is inherited.
3079 if Ctype >= Subtype_Conformant then
3080 if Convention (Old_Id) /= Convention (New_Id) then
3082 if not Is_Frozen (New_Id) then
3083 null;
3085 elsif Present (Err_Loc)
3086 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
3087 and then Present (Corresponding_Spec (Err_Loc))
3088 then
3089 Error_Msg_Name_1 := Chars (New_Id);
3090 Error_Msg_Name_2 :=
3091 Name_Ada + Convention_Id'Pos (Convention (New_Id));
3093 Conformance_Error ("\prior declaration for% has convention %!");
3095 else
3096 Conformance_Error ("\calling conventions do not match!");
3097 end if;
3099 return;
3101 elsif Is_Formal_Subprogram (Old_Id)
3102 or else Is_Formal_Subprogram (New_Id)
3103 then
3104 Conformance_Error ("\formal subprograms not allowed!");
3105 return;
3106 end if;
3107 end if;
3109 -- Deal with parameters
3111 -- Note: we use the entity information, rather than going directly
3112 -- to the specification in the tree. This is not only simpler, but
3113 -- absolutely necessary for some cases of conformance tests between
3114 -- operators, where the declaration tree simply does not exist!
3116 Old_Formal := First_Formal (Old_Id);
3117 New_Formal := First_Formal (New_Id);
3119 while Present (Old_Formal) and then Present (New_Formal) loop
3120 if Is_Controlling_Formal (Old_Formal)
3121 and then Is_Controlling_Formal (New_Formal)
3122 and then Skip_Controlling_Formals
3123 then
3124 goto Skip_Controlling_Formal;
3125 end if;
3127 if Ctype = Fully_Conformant then
3129 -- Names must match. Error message is more accurate if we do
3130 -- this before checking that the types of the formals match.
3132 if Chars (Old_Formal) /= Chars (New_Formal) then
3133 Conformance_Error ("\name & does not match!", New_Formal);
3135 -- Set error posted flag on new formal as well to stop
3136 -- junk cascaded messages in some cases.
3138 Set_Error_Posted (New_Formal);
3139 return;
3140 end if;
3141 end if;
3143 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
3144 -- case occurs whenever a subprogram is being renamed and one of its
3145 -- parameters imposes a null exclusion. For example:
3147 -- type T is null record;
3148 -- type Acc_T is access T;
3149 -- subtype Acc_T_Sub is Acc_T;
3151 -- procedure P (Obj : not null Acc_T_Sub); -- itype
3152 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
3153 -- renames P;
3155 Old_Formal_Base := Etype (Old_Formal);
3156 New_Formal_Base := Etype (New_Formal);
3158 if Get_Inst then
3159 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
3160 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
3161 end if;
3163 Access_Types_Match := Ada_Version >= Ada_05
3165 -- Ensure that this rule is only applied when New_Id is a
3166 -- renaming of Old_Id.
3168 and then Nkind (Parent (Parent (New_Id))) =
3169 N_Subprogram_Renaming_Declaration
3170 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
3171 and then Present (Entity (Name (Parent (Parent (New_Id)))))
3172 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
3174 -- Now handle the allowed access-type case
3176 and then Is_Access_Type (Old_Formal_Base)
3177 and then Is_Access_Type (New_Formal_Base)
3179 -- The type kinds must match. The only exception occurs with
3180 -- multiple generics of the form:
3182 -- generic generic
3183 -- type F is private; type A is private;
3184 -- type F_Ptr is access F; type A_Ptr is access A;
3185 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
3186 -- package F_Pack is ... package A_Pack is
3187 -- package F_Inst is
3188 -- new F_Pack (A, A_Ptr, A_P);
3190 -- When checking for conformance between the parameters of A_P
3191 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
3192 -- because the compiler has transformed A_Ptr into a subtype of
3193 -- F_Ptr. We catch this case in the code below.
3195 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
3196 or else
3197 (Is_Generic_Type (Old_Formal_Base)
3198 and then Is_Generic_Type (New_Formal_Base)
3199 and then Is_Internal (New_Formal_Base)
3200 and then Etype (Etype (New_Formal_Base)) =
3201 Old_Formal_Base))
3202 and then Directly_Designated_Type (Old_Formal_Base) =
3203 Directly_Designated_Type (New_Formal_Base)
3204 and then ((Is_Itype (Old_Formal_Base)
3205 and then Can_Never_Be_Null (Old_Formal_Base))
3206 or else
3207 (Is_Itype (New_Formal_Base)
3208 and then Can_Never_Be_Null (New_Formal_Base)));
3210 -- Types must always match. In the visible part of an instance,
3211 -- usual overloading rules for dispatching operations apply, and
3212 -- we check base types (not the actual subtypes).
3214 if In_Instance_Visible_Part
3215 and then Is_Dispatching_Operation (New_Id)
3216 then
3217 if not Conforming_Types
3218 (T1 => Base_Type (Etype (Old_Formal)),
3219 T2 => Base_Type (Etype (New_Formal)),
3220 Ctype => Ctype,
3221 Get_Inst => Get_Inst)
3222 and then not Access_Types_Match
3223 then
3224 Conformance_Error ("\type of & does not match!", New_Formal);
3225 return;
3226 end if;
3228 elsif not Conforming_Types
3229 (T1 => Old_Formal_Base,
3230 T2 => New_Formal_Base,
3231 Ctype => Ctype,
3232 Get_Inst => Get_Inst)
3233 and then not Access_Types_Match
3234 then
3235 Conformance_Error ("\type of & does not match!", New_Formal);
3236 return;
3237 end if;
3239 -- For mode conformance, mode must match
3241 if Ctype >= Mode_Conformant then
3242 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
3243 Conformance_Error ("\mode of & does not match!", New_Formal);
3244 return;
3246 -- Part of mode conformance for access types is having the same
3247 -- constant modifier.
3249 elsif Access_Types_Match
3250 and then Is_Access_Constant (Old_Formal_Base) /=
3251 Is_Access_Constant (New_Formal_Base)
3252 then
3253 Conformance_Error
3254 ("\constant modifier does not match!", New_Formal);
3255 return;
3256 end if;
3257 end if;
3259 if Ctype >= Subtype_Conformant then
3261 -- Ada 2005 (AI-231): In case of anonymous access types check
3262 -- the null-exclusion and access-to-constant attributes must
3263 -- match.
3265 if Ada_Version >= Ada_05
3266 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
3267 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
3268 and then
3269 (Can_Never_Be_Null (Old_Formal) /=
3270 Can_Never_Be_Null (New_Formal)
3271 or else
3272 Is_Access_Constant (Etype (Old_Formal)) /=
3273 Is_Access_Constant (Etype (New_Formal)))
3274 then
3275 -- It is allowed to omit the null-exclusion in case of stream
3276 -- attribute subprograms. We recognize stream subprograms
3277 -- through their TSS-generated suffix.
3279 declare
3280 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
3281 begin
3282 if TSS_Name /= TSS_Stream_Read
3283 and then TSS_Name /= TSS_Stream_Write
3284 and then TSS_Name /= TSS_Stream_Input
3285 and then TSS_Name /= TSS_Stream_Output
3286 then
3287 Conformance_Error
3288 ("\type of & does not match!", New_Formal);
3289 return;
3290 end if;
3291 end;
3292 end if;
3293 end if;
3295 -- Full conformance checks
3297 if Ctype = Fully_Conformant then
3299 -- We have checked already that names match
3301 if Parameter_Mode (Old_Formal) = E_In_Parameter then
3303 -- Check default expressions for in parameters
3305 declare
3306 NewD : constant Boolean :=
3307 Present (Default_Value (New_Formal));
3308 OldD : constant Boolean :=
3309 Present (Default_Value (Old_Formal));
3310 begin
3311 if NewD or OldD then
3313 -- The old default value has been analyzed because the
3314 -- current full declaration will have frozen everything
3315 -- before. The new default value has not been analyzed,
3316 -- so analyze it now before we check for conformance.
3318 if NewD then
3319 Push_Scope (New_Id);
3320 Analyze_Per_Use_Expression
3321 (Default_Value (New_Formal), Etype (New_Formal));
3322 End_Scope;
3323 end if;
3325 if not (NewD and OldD)
3326 or else not Fully_Conformant_Expressions
3327 (Default_Value (Old_Formal),
3328 Default_Value (New_Formal))
3329 then
3330 Conformance_Error
3331 ("\default expression for & does not match!",
3332 New_Formal);
3333 return;
3334 end if;
3335 end if;
3336 end;
3337 end if;
3338 end if;
3340 -- A couple of special checks for Ada 83 mode. These checks are
3341 -- skipped if either entity is an operator in package Standard,
3342 -- or if either old or new instance is not from the source program.
3344 if Ada_Version = Ada_83
3345 and then Sloc (Old_Id) > Standard_Location
3346 and then Sloc (New_Id) > Standard_Location
3347 and then Comes_From_Source (Old_Id)
3348 and then Comes_From_Source (New_Id)
3349 then
3350 declare
3351 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
3352 New_Param : constant Node_Id := Declaration_Node (New_Formal);
3354 begin
3355 -- Explicit IN must be present or absent in both cases. This
3356 -- test is required only in the full conformance case.
3358 if In_Present (Old_Param) /= In_Present (New_Param)
3359 and then Ctype = Fully_Conformant
3360 then
3361 Conformance_Error
3362 ("\(Ada 83) IN must appear in both declarations",
3363 New_Formal);
3364 return;
3365 end if;
3367 -- Grouping (use of comma in param lists) must be the same
3368 -- This is where we catch a misconformance like:
3370 -- A, B : Integer
3371 -- A : Integer; B : Integer
3373 -- which are represented identically in the tree except
3374 -- for the setting of the flags More_Ids and Prev_Ids.
3376 if More_Ids (Old_Param) /= More_Ids (New_Param)
3377 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
3378 then
3379 Conformance_Error
3380 ("\grouping of & does not match!", New_Formal);
3381 return;
3382 end if;
3383 end;
3384 end if;
3386 -- This label is required when skipping controlling formals
3388 <<Skip_Controlling_Formal>>
3390 Next_Formal (Old_Formal);
3391 Next_Formal (New_Formal);
3392 end loop;
3394 if Present (Old_Formal) then
3395 Conformance_Error ("\too few parameters!");
3396 return;
3398 elsif Present (New_Formal) then
3399 Conformance_Error ("\too many parameters!", New_Formal);
3400 return;
3401 end if;
3402 end Check_Conformance;
3404 -----------------------
3405 -- Check_Conventions --
3406 -----------------------
3408 procedure Check_Conventions (Typ : Entity_Id) is
3410 function Skip_Check (Op : Entity_Id) return Boolean;
3411 pragma Inline (Skip_Check);
3412 -- A small optimization: skip the predefined dispatching operations,
3413 -- since they always have the same convention. Also do not consider
3414 -- abstract primitives since those are left by an erroneous overriding.
3415 -- This function returns True for any operation that is thus exempted
3416 -- exempted from checking.
3418 procedure Check_Convention
3419 (Op : Entity_Id;
3420 Search_From : Elmt_Id);
3421 -- Verify that the convention of inherited dispatching operation Op is
3422 -- consistent among all subprograms it overrides. In order to minimize
3423 -- the search, Search_From is utilized to designate a specific point in
3424 -- the list rather than iterating over the whole list once more.
3426 ----------------------
3427 -- Check_Convention --
3428 ----------------------
3430 procedure Check_Convention
3431 (Op : Entity_Id;
3432 Search_From : Elmt_Id)
3434 procedure Error_Msg_Operation (Op : Entity_Id);
3435 -- Emit a continuation to an error message depicting the kind, name,
3436 -- convention and source location of subprogram Op.
3438 -------------------------
3439 -- Error_Msg_Operation --
3440 -------------------------
3442 procedure Error_Msg_Operation (Op : Entity_Id) is
3443 begin
3444 Error_Msg_Name_1 := Chars (Op);
3446 -- Error messages of primitive subprograms do not contain a
3447 -- convention attribute since the convention may have been first
3448 -- inherited from a parent subprogram, then changed by a pragma.
3450 if Comes_From_Source (Op) then
3451 Error_Msg_Sloc := Sloc (Op);
3452 Error_Msg_N
3453 ("\ primitive % defined #", Typ);
3455 else
3456 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
3458 if Present (Abstract_Interface_Alias (Op)) then
3459 Error_Msg_Sloc := Sloc (Abstract_Interface_Alias (Op));
3460 Error_Msg_N ("\\overridden operation % with " &
3461 "convention % defined #", Typ);
3463 else pragma Assert (Present (Alias (Op)));
3464 Error_Msg_Sloc := Sloc (Alias (Op));
3465 Error_Msg_N ("\\inherited operation % with " &
3466 "convention % defined #", Typ);
3467 end if;
3468 end if;
3469 end Error_Msg_Operation;
3471 -- Local variables
3473 Second_Prim_Op : Entity_Id;
3474 Second_Prim_Op_Elmt : Elmt_Id;
3476 -- Start of processing for Check_Convention
3478 begin
3479 Second_Prim_Op_Elmt := Next_Elmt (Search_From);
3480 while Present (Second_Prim_Op_Elmt) loop
3481 Second_Prim_Op := Node (Second_Prim_Op_Elmt);
3483 if not Skip_Check (Second_Prim_Op)
3484 and then Chars (Second_Prim_Op) = Chars (Op)
3485 and then Type_Conformant (Second_Prim_Op, Op)
3486 and then Convention (Second_Prim_Op) /= Convention (Op)
3487 then
3488 Error_Msg_N
3489 ("inconsistent conventions in primitive operations", Typ);
3491 Error_Msg_Operation (Op);
3492 Error_Msg_Operation (Second_Prim_Op);
3494 -- Avoid cascading errors
3496 return;
3497 end if;
3499 Next_Elmt (Second_Prim_Op_Elmt);
3500 end loop;
3501 end Check_Convention;
3503 ----------------
3504 -- Skip_Check --
3505 ----------------
3507 function Skip_Check (Op : Entity_Id) return Boolean is
3508 begin
3509 return Is_Predefined_Dispatching_Operation (Op)
3510 or else Is_Abstract_Subprogram (Op);
3511 end Skip_Check;
3513 -- Local variables
3515 Prim_Op : Entity_Id;
3516 Prim_Op_Elmt : Elmt_Id;
3518 -- Start of processing for Check_Conventions
3520 begin
3521 -- The algorithm checks every overriding dispatching operation against
3522 -- all the corresponding overridden dispatching operations, detecting
3523 -- differences in coventions.
3525 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
3526 while Present (Prim_Op_Elmt) loop
3527 Prim_Op := Node (Prim_Op_Elmt);
3529 -- A small optimization: skip the predefined dispatching operations
3530 -- since they always have the same convention. Also avoid processing
3531 -- of abstract primitives left from an erroneous overriding.
3533 if not Skip_Check (Prim_Op) then
3534 Check_Convention
3535 (Op => Prim_Op,
3536 Search_From => Prim_Op_Elmt);
3537 end if;
3539 Next_Elmt (Prim_Op_Elmt);
3540 end loop;
3541 end Check_Conventions;
3543 ------------------------------
3544 -- Check_Delayed_Subprogram --
3545 ------------------------------
3547 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
3548 F : Entity_Id;
3550 procedure Possible_Freeze (T : Entity_Id);
3551 -- T is the type of either a formal parameter or of the return type.
3552 -- If T is not yet frozen and needs a delayed freeze, then the
3553 -- subprogram itself must be delayed.
3555 ---------------------
3556 -- Possible_Freeze --
3557 ---------------------
3559 procedure Possible_Freeze (T : Entity_Id) is
3560 begin
3561 if Has_Delayed_Freeze (T)
3562 and then not Is_Frozen (T)
3563 then
3564 Set_Has_Delayed_Freeze (Designator);
3566 elsif Is_Access_Type (T)
3567 and then Has_Delayed_Freeze (Designated_Type (T))
3568 and then not Is_Frozen (Designated_Type (T))
3569 then
3570 Set_Has_Delayed_Freeze (Designator);
3571 end if;
3572 end Possible_Freeze;
3574 -- Start of processing for Check_Delayed_Subprogram
3576 begin
3577 -- Never need to freeze abstract subprogram
3579 if Ekind (Designator) /= E_Subprogram_Type
3580 and then Is_Abstract_Subprogram (Designator)
3581 then
3582 null;
3583 else
3584 -- Need delayed freeze if return type itself needs a delayed
3585 -- freeze and is not yet frozen.
3587 Possible_Freeze (Etype (Designator));
3588 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
3590 -- Need delayed freeze if any of the formal types themselves need
3591 -- a delayed freeze and are not yet frozen.
3593 F := First_Formal (Designator);
3594 while Present (F) loop
3595 Possible_Freeze (Etype (F));
3596 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
3597 Next_Formal (F);
3598 end loop;
3599 end if;
3601 -- Mark functions that return by reference. Note that it cannot be
3602 -- done for delayed_freeze subprograms because the underlying
3603 -- returned type may not be known yet (for private types)
3605 if not Has_Delayed_Freeze (Designator)
3606 and then Expander_Active
3607 then
3608 declare
3609 Typ : constant Entity_Id := Etype (Designator);
3610 Utyp : constant Entity_Id := Underlying_Type (Typ);
3612 begin
3613 if Is_Inherently_Limited_Type (Typ) then
3614 Set_Returns_By_Ref (Designator);
3616 elsif Present (Utyp) and then CW_Or_Controlled_Type (Utyp) then
3617 Set_Returns_By_Ref (Designator);
3618 end if;
3619 end;
3620 end if;
3621 end Check_Delayed_Subprogram;
3623 ------------------------------------
3624 -- Check_Discriminant_Conformance --
3625 ------------------------------------
3627 procedure Check_Discriminant_Conformance
3628 (N : Node_Id;
3629 Prev : Entity_Id;
3630 Prev_Loc : Node_Id)
3632 Old_Discr : Entity_Id := First_Discriminant (Prev);
3633 New_Discr : Node_Id := First (Discriminant_Specifications (N));
3634 New_Discr_Id : Entity_Id;
3635 New_Discr_Type : Entity_Id;
3637 procedure Conformance_Error (Msg : String; N : Node_Id);
3638 -- Post error message for conformance error on given node. Two messages
3639 -- are output. The first points to the previous declaration with a
3640 -- general "no conformance" message. The second is the detailed reason,
3641 -- supplied as Msg. The parameter N provide information for a possible
3642 -- & insertion in the message.
3644 -----------------------
3645 -- Conformance_Error --
3646 -----------------------
3648 procedure Conformance_Error (Msg : String; N : Node_Id) is
3649 begin
3650 Error_Msg_Sloc := Sloc (Prev_Loc);
3651 Error_Msg_N ("not fully conformant with declaration#!", N);
3652 Error_Msg_NE (Msg, N, N);
3653 end Conformance_Error;
3655 -- Start of processing for Check_Discriminant_Conformance
3657 begin
3658 while Present (Old_Discr) and then Present (New_Discr) loop
3660 New_Discr_Id := Defining_Identifier (New_Discr);
3662 -- The subtype mark of the discriminant on the full type has not
3663 -- been analyzed so we do it here. For an access discriminant a new
3664 -- type is created.
3666 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
3667 New_Discr_Type :=
3668 Access_Definition (N, Discriminant_Type (New_Discr));
3670 else
3671 Analyze (Discriminant_Type (New_Discr));
3672 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
3673 end if;
3675 if not Conforming_Types
3676 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
3677 then
3678 Conformance_Error ("type of & does not match!", New_Discr_Id);
3679 return;
3680 else
3681 -- Treat the new discriminant as an occurrence of the old one,
3682 -- for navigation purposes, and fill in some semantic
3683 -- information, for completeness.
3685 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
3686 Set_Etype (New_Discr_Id, Etype (Old_Discr));
3687 Set_Scope (New_Discr_Id, Scope (Old_Discr));
3688 end if;
3690 -- Names must match
3692 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
3693 Conformance_Error ("name & does not match!", New_Discr_Id);
3694 return;
3695 end if;
3697 -- Default expressions must match
3699 declare
3700 NewD : constant Boolean :=
3701 Present (Expression (New_Discr));
3702 OldD : constant Boolean :=
3703 Present (Expression (Parent (Old_Discr)));
3705 begin
3706 if NewD or OldD then
3708 -- The old default value has been analyzed and expanded,
3709 -- because the current full declaration will have frozen
3710 -- everything before. The new default values have not been
3711 -- expanded, so expand now to check conformance.
3713 if NewD then
3714 Analyze_Per_Use_Expression
3715 (Expression (New_Discr), New_Discr_Type);
3716 end if;
3718 if not (NewD and OldD)
3719 or else not Fully_Conformant_Expressions
3720 (Expression (Parent (Old_Discr)),
3721 Expression (New_Discr))
3723 then
3724 Conformance_Error
3725 ("default expression for & does not match!",
3726 New_Discr_Id);
3727 return;
3728 end if;
3729 end if;
3730 end;
3732 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
3734 if Ada_Version = Ada_83 then
3735 declare
3736 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
3738 begin
3739 -- Grouping (use of comma in param lists) must be the same
3740 -- This is where we catch a misconformance like:
3742 -- A,B : Integer
3743 -- A : Integer; B : Integer
3745 -- which are represented identically in the tree except
3746 -- for the setting of the flags More_Ids and Prev_Ids.
3748 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
3749 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
3750 then
3751 Conformance_Error
3752 ("grouping of & does not match!", New_Discr_Id);
3753 return;
3754 end if;
3755 end;
3756 end if;
3758 Next_Discriminant (Old_Discr);
3759 Next (New_Discr);
3760 end loop;
3762 if Present (Old_Discr) then
3763 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
3764 return;
3766 elsif Present (New_Discr) then
3767 Conformance_Error
3768 ("too many discriminants!", Defining_Identifier (New_Discr));
3769 return;
3770 end if;
3771 end Check_Discriminant_Conformance;
3773 ----------------------------
3774 -- Check_Fully_Conformant --
3775 ----------------------------
3777 procedure Check_Fully_Conformant
3778 (New_Id : Entity_Id;
3779 Old_Id : Entity_Id;
3780 Err_Loc : Node_Id := Empty)
3782 Result : Boolean;
3783 begin
3784 Check_Conformance
3785 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
3786 end Check_Fully_Conformant;
3788 ---------------------------
3789 -- Check_Mode_Conformant --
3790 ---------------------------
3792 procedure Check_Mode_Conformant
3793 (New_Id : Entity_Id;
3794 Old_Id : Entity_Id;
3795 Err_Loc : Node_Id := Empty;
3796 Get_Inst : Boolean := False)
3798 Result : Boolean;
3800 begin
3801 Check_Conformance
3802 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
3803 end Check_Mode_Conformant;
3805 --------------------------------
3806 -- Check_Overriding_Indicator --
3807 --------------------------------
3809 procedure Check_Overriding_Indicator
3810 (Subp : Entity_Id;
3811 Overridden_Subp : Entity_Id;
3812 Is_Primitive : Boolean)
3814 Decl : Node_Id;
3815 Spec : Node_Id;
3817 begin
3818 -- No overriding indicator for literals
3820 if Ekind (Subp) = E_Enumeration_Literal then
3821 return;
3823 elsif Ekind (Subp) = E_Entry then
3824 Decl := Parent (Subp);
3826 else
3827 Decl := Unit_Declaration_Node (Subp);
3828 end if;
3830 if Nkind (Decl) = N_Subprogram_Body
3831 or else Nkind (Decl) = N_Subprogram_Body_Stub
3832 or else Nkind (Decl) = N_Subprogram_Declaration
3833 or else Nkind (Decl) = N_Abstract_Subprogram_Declaration
3834 or else Nkind (Decl) = N_Subprogram_Renaming_Declaration
3835 then
3836 Spec := Specification (Decl);
3838 elsif Nkind (Decl) = N_Entry_Declaration then
3839 Spec := Decl;
3841 else
3842 return;
3843 end if;
3845 if Present (Overridden_Subp) then
3846 if Must_Not_Override (Spec) then
3847 Error_Msg_Sloc := Sloc (Overridden_Subp);
3849 if Ekind (Subp) = E_Entry then
3850 Error_Msg_NE
3851 ("entry & overrides inherited operation #", Spec, Subp);
3852 else
3853 Error_Msg_NE
3854 ("subprogram & overrides inherited operation #", Spec, Subp);
3855 end if;
3856 end if;
3858 -- If Subp is an operator, it may override a predefined operation.
3859 -- In that case overridden_subp is empty because of our implicit
3860 -- representation for predefined operators. We have to check whether the
3861 -- signature of Subp matches that of a predefined operator. Note that
3862 -- first argument provides the name of the operator, and the second
3863 -- argument the signature that may match that of a standard operation.
3865 elsif Nkind (Subp) = N_Defining_Operator_Symbol
3866 and then Must_Not_Override (Spec)
3867 then
3868 if Operator_Matches_Spec (Subp, Subp) then
3869 Error_Msg_NE
3870 ("subprogram & overrides predefined operator ",
3871 Spec, Subp);
3872 end if;
3874 elsif Must_Override (Spec) then
3875 if Ekind (Subp) = E_Entry then
3876 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
3878 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
3879 if not Operator_Matches_Spec (Subp, Subp) then
3880 Error_Msg_NE
3881 ("subprogram & is not overriding", Spec, Subp);
3882 end if;
3884 else
3885 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
3886 end if;
3888 -- If the operation is marked "not overriding" and it's not primitive
3889 -- then an error is issued, unless this is an operation of a task or
3890 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
3891 -- has been specified have already been checked above.
3893 elsif Must_Not_Override (Spec)
3894 and then not Is_Primitive
3895 and then Ekind (Subp) /= E_Entry
3896 and then Ekind (Scope (Subp)) /= E_Protected_Type
3897 then
3898 Error_Msg_N
3899 ("overriding indicator only allowed if subprogram is primitive",
3900 Subp);
3902 return;
3903 end if;
3904 end Check_Overriding_Indicator;
3906 -------------------
3907 -- Check_Returns --
3908 -------------------
3910 -- Note: this procedure needs to know far too much about how the expander
3911 -- messes with exceptions. The use of the flag Exception_Junk and the
3912 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
3913 -- works, but is not very clean. It would be better if the expansion
3914 -- routines would leave Original_Node working nicely, and we could use
3915 -- Original_Node here to ignore all the peculiar expander messing ???
3917 procedure Check_Returns
3918 (HSS : Node_Id;
3919 Mode : Character;
3920 Err : out Boolean;
3921 Proc : Entity_Id := Empty)
3923 Handler : Node_Id;
3925 procedure Check_Statement_Sequence (L : List_Id);
3926 -- Internal recursive procedure to check a list of statements for proper
3927 -- termination by a return statement (or a transfer of control or a
3928 -- compound statement that is itself internally properly terminated).
3930 ------------------------------
3931 -- Check_Statement_Sequence --
3932 ------------------------------
3934 procedure Check_Statement_Sequence (L : List_Id) is
3935 Last_Stm : Node_Id;
3936 Stm : Node_Id;
3937 Kind : Node_Kind;
3939 Raise_Exception_Call : Boolean;
3940 -- Set True if statement sequence terminated by Raise_Exception call
3941 -- or a Reraise_Occurrence call.
3943 begin
3944 Raise_Exception_Call := False;
3946 -- Get last real statement
3948 Last_Stm := Last (L);
3950 -- Deal with digging out exception handler statement sequences that
3951 -- have been transformed by the local raise to goto optimization.
3952 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
3953 -- optimization has occurred, we are looking at something like:
3955 -- begin
3956 -- original stmts in block
3958 -- exception \
3959 -- when excep1 => |
3960 -- goto L1; | omitted if No_Exception_Propagation
3961 -- when excep2 => |
3962 -- goto L2; /
3963 -- end;
3965 -- goto L3; -- skip handler when exception not raised
3967 -- <<L1>> -- target label for local exception
3968 -- begin
3969 -- estmts1
3970 -- end;
3972 -- goto L3;
3974 -- <<L2>>
3975 -- begin
3976 -- estmts2
3977 -- end;
3979 -- <<L3>>
3981 -- and what we have to do is to dig out the estmts1 and estmts2
3982 -- sequences (which were the original sequences of statements in
3983 -- the exception handlers) and check them.
3985 if Nkind (Last_Stm) = N_Label
3986 and then Exception_Junk (Last_Stm)
3987 then
3988 Stm := Last_Stm;
3989 loop
3990 Prev (Stm);
3991 exit when No (Stm);
3992 exit when Nkind (Stm) /= N_Block_Statement;
3993 exit when not Exception_Junk (Stm);
3994 Prev (Stm);
3995 exit when No (Stm);
3996 exit when Nkind (Stm) /= N_Label;
3997 exit when not Exception_Junk (Stm);
3998 Check_Statement_Sequence
3999 (Statements (Handled_Statement_Sequence (Next (Stm))));
4001 Prev (Stm);
4002 Last_Stm := Stm;
4003 exit when No (Stm);
4004 exit when Nkind (Stm) /= N_Goto_Statement;
4005 exit when not Exception_Junk (Stm);
4006 end loop;
4007 end if;
4009 -- Don't count pragmas
4011 while Nkind (Last_Stm) = N_Pragma
4013 -- Don't count call to SS_Release (can happen after Raise_Exception)
4015 or else
4016 (Nkind (Last_Stm) = N_Procedure_Call_Statement
4017 and then
4018 Nkind (Name (Last_Stm)) = N_Identifier
4019 and then
4020 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
4022 -- Don't count exception junk
4024 or else
4025 ((Nkind (Last_Stm) = N_Goto_Statement
4026 or else Nkind (Last_Stm) = N_Label
4027 or else Nkind (Last_Stm) = N_Object_Declaration)
4028 and then Exception_Junk (Last_Stm))
4029 or else Nkind (Last_Stm) in N_Push_xxx_Label
4030 or else Nkind (Last_Stm) in N_Pop_xxx_Label
4031 loop
4032 Prev (Last_Stm);
4033 end loop;
4035 -- Here we have the "real" last statement
4037 Kind := Nkind (Last_Stm);
4039 -- Transfer of control, OK. Note that in the No_Return procedure
4040 -- case, we already diagnosed any explicit return statements, so
4041 -- we can treat them as OK in this context.
4043 if Is_Transfer (Last_Stm) then
4044 return;
4046 -- Check cases of explicit non-indirect procedure calls
4048 elsif Kind = N_Procedure_Call_Statement
4049 and then Is_Entity_Name (Name (Last_Stm))
4050 then
4051 -- Check call to Raise_Exception procedure which is treated
4052 -- specially, as is a call to Reraise_Occurrence.
4054 -- We suppress the warning in these cases since it is likely that
4055 -- the programmer really does not expect to deal with the case
4056 -- of Null_Occurrence, and thus would find a warning about a
4057 -- missing return curious, and raising Program_Error does not
4058 -- seem such a bad behavior if this does occur.
4060 -- Note that in the Ada 2005 case for Raise_Exception, the actual
4061 -- behavior will be to raise Constraint_Error (see AI-329).
4063 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
4064 or else
4065 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
4066 then
4067 Raise_Exception_Call := True;
4069 -- For Raise_Exception call, test first argument, if it is
4070 -- an attribute reference for a 'Identity call, then we know
4071 -- that the call cannot possibly return.
4073 declare
4074 Arg : constant Node_Id :=
4075 Original_Node (First_Actual (Last_Stm));
4076 begin
4077 if Nkind (Arg) = N_Attribute_Reference
4078 and then Attribute_Name (Arg) = Name_Identity
4079 then
4080 return;
4081 end if;
4082 end;
4083 end if;
4085 -- If statement, need to look inside if there is an else and check
4086 -- each constituent statement sequence for proper termination.
4088 elsif Kind = N_If_Statement
4089 and then Present (Else_Statements (Last_Stm))
4090 then
4091 Check_Statement_Sequence (Then_Statements (Last_Stm));
4092 Check_Statement_Sequence (Else_Statements (Last_Stm));
4094 if Present (Elsif_Parts (Last_Stm)) then
4095 declare
4096 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
4098 begin
4099 while Present (Elsif_Part) loop
4100 Check_Statement_Sequence (Then_Statements (Elsif_Part));
4101 Next (Elsif_Part);
4102 end loop;
4103 end;
4104 end if;
4106 return;
4108 -- Case statement, check each case for proper termination
4110 elsif Kind = N_Case_Statement then
4111 declare
4112 Case_Alt : Node_Id;
4114 begin
4115 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
4116 while Present (Case_Alt) loop
4117 Check_Statement_Sequence (Statements (Case_Alt));
4118 Next_Non_Pragma (Case_Alt);
4119 end loop;
4120 end;
4122 return;
4124 -- Block statement, check its handled sequence of statements
4126 elsif Kind = N_Block_Statement then
4127 declare
4128 Err1 : Boolean;
4130 begin
4131 Check_Returns
4132 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
4134 if Err1 then
4135 Err := True;
4136 end if;
4138 return;
4139 end;
4141 -- Loop statement. If there is an iteration scheme, we can definitely
4142 -- fall out of the loop. Similarly if there is an exit statement, we
4143 -- can fall out. In either case we need a following return.
4145 elsif Kind = N_Loop_Statement then
4146 if Present (Iteration_Scheme (Last_Stm))
4147 or else Has_Exit (Entity (Identifier (Last_Stm)))
4148 then
4149 null;
4151 -- A loop with no exit statement or iteration scheme if either
4152 -- an inifite loop, or it has some other exit (raise/return).
4153 -- In either case, no warning is required.
4155 else
4156 return;
4157 end if;
4159 -- Timed entry call, check entry call and delay alternatives
4161 -- Note: in expanded code, the timed entry call has been converted
4162 -- to a set of expanded statements on which the check will work
4163 -- correctly in any case.
4165 elsif Kind = N_Timed_Entry_Call then
4166 declare
4167 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4168 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
4170 begin
4171 -- If statement sequence of entry call alternative is missing,
4172 -- then we can definitely fall through, and we post the error
4173 -- message on the entry call alternative itself.
4175 if No (Statements (ECA)) then
4176 Last_Stm := ECA;
4178 -- If statement sequence of delay alternative is missing, then
4179 -- we can definitely fall through, and we post the error
4180 -- message on the delay alternative itself.
4182 -- Note: if both ECA and DCA are missing the return, then we
4183 -- post only one message, should be enough to fix the bugs.
4184 -- If not we will get a message next time on the DCA when the
4185 -- ECA is fixed!
4187 elsif No (Statements (DCA)) then
4188 Last_Stm := DCA;
4190 -- Else check both statement sequences
4192 else
4193 Check_Statement_Sequence (Statements (ECA));
4194 Check_Statement_Sequence (Statements (DCA));
4195 return;
4196 end if;
4197 end;
4199 -- Conditional entry call, check entry call and else part
4201 -- Note: in expanded code, the conditional entry call has been
4202 -- converted to a set of expanded statements on which the check
4203 -- will work correctly in any case.
4205 elsif Kind = N_Conditional_Entry_Call then
4206 declare
4207 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4209 begin
4210 -- If statement sequence of entry call alternative is missing,
4211 -- then we can definitely fall through, and we post the error
4212 -- message on the entry call alternative itself.
4214 if No (Statements (ECA)) then
4215 Last_Stm := ECA;
4217 -- Else check statement sequence and else part
4219 else
4220 Check_Statement_Sequence (Statements (ECA));
4221 Check_Statement_Sequence (Else_Statements (Last_Stm));
4222 return;
4223 end if;
4224 end;
4225 end if;
4227 -- If we fall through, issue appropriate message
4229 if Mode = 'F' then
4230 if not Raise_Exception_Call then
4231 Error_Msg_N
4232 ("?RETURN statement missing following this statement!",
4233 Last_Stm);
4234 Error_Msg_N
4235 ("\?Program_Error may be raised at run time!",
4236 Last_Stm);
4237 end if;
4239 -- Note: we set Err even though we have not issued a warning
4240 -- because we still have a case of a missing return. This is
4241 -- an extremely marginal case, probably will never be noticed
4242 -- but we might as well get it right.
4244 Err := True;
4246 -- Otherwise we have the case of a procedure marked No_Return
4248 else
4249 Error_Msg_N
4250 ("?implied return after this statement will raise Program_Error",
4251 Last_Stm);
4252 Error_Msg_NE
4253 ("?procedure & is marked as No_Return",
4254 Last_Stm, Proc);
4256 declare
4257 RE : constant Node_Id :=
4258 Make_Raise_Program_Error (Sloc (Last_Stm),
4259 Reason => PE_Implicit_Return);
4260 begin
4261 Insert_After (Last_Stm, RE);
4262 Analyze (RE);
4263 end;
4264 end if;
4265 end Check_Statement_Sequence;
4267 -- Start of processing for Check_Returns
4269 begin
4270 Err := False;
4271 Check_Statement_Sequence (Statements (HSS));
4273 if Present (Exception_Handlers (HSS)) then
4274 Handler := First_Non_Pragma (Exception_Handlers (HSS));
4275 while Present (Handler) loop
4276 Check_Statement_Sequence (Statements (Handler));
4277 Next_Non_Pragma (Handler);
4278 end loop;
4279 end if;
4280 end Check_Returns;
4282 ----------------------------
4283 -- Check_Subprogram_Order --
4284 ----------------------------
4286 procedure Check_Subprogram_Order (N : Node_Id) is
4288 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
4289 -- This is used to check if S1 > S2 in the sense required by this
4290 -- test, for example nameab < namec, but name2 < name10.
4292 -----------------------------
4293 -- Subprogram_Name_Greater --
4294 -----------------------------
4296 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
4297 L1, L2 : Positive;
4298 N1, N2 : Natural;
4300 begin
4301 -- Remove trailing numeric parts
4303 L1 := S1'Last;
4304 while S1 (L1) in '0' .. '9' loop
4305 L1 := L1 - 1;
4306 end loop;
4308 L2 := S2'Last;
4309 while S2 (L2) in '0' .. '9' loop
4310 L2 := L2 - 1;
4311 end loop;
4313 -- If non-numeric parts non-equal, that's decisive
4315 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
4316 return False;
4318 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
4319 return True;
4321 -- If non-numeric parts equal, compare suffixed numeric parts. Note
4322 -- that a missing suffix is treated as numeric zero in this test.
4324 else
4325 N1 := 0;
4326 while L1 < S1'Last loop
4327 L1 := L1 + 1;
4328 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
4329 end loop;
4331 N2 := 0;
4332 while L2 < S2'Last loop
4333 L2 := L2 + 1;
4334 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
4335 end loop;
4337 return N1 > N2;
4338 end if;
4339 end Subprogram_Name_Greater;
4341 -- Start of processing for Check_Subprogram_Order
4343 begin
4344 -- Check body in alpha order if this is option
4346 if Style_Check
4347 and then Style_Check_Order_Subprograms
4348 and then Nkind (N) = N_Subprogram_Body
4349 and then Comes_From_Source (N)
4350 and then In_Extended_Main_Source_Unit (N)
4351 then
4352 declare
4353 LSN : String_Ptr
4354 renames Scope_Stack.Table
4355 (Scope_Stack.Last).Last_Subprogram_Name;
4357 Body_Id : constant Entity_Id :=
4358 Defining_Entity (Specification (N));
4360 begin
4361 Get_Decoded_Name_String (Chars (Body_Id));
4363 if LSN /= null then
4364 if Subprogram_Name_Greater
4365 (LSN.all, Name_Buffer (1 .. Name_Len))
4366 then
4367 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
4368 end if;
4370 Free (LSN);
4371 end if;
4373 LSN := new String'(Name_Buffer (1 .. Name_Len));
4374 end;
4375 end if;
4376 end Check_Subprogram_Order;
4378 ------------------------------
4379 -- Check_Subtype_Conformant --
4380 ------------------------------
4382 procedure Check_Subtype_Conformant
4383 (New_Id : Entity_Id;
4384 Old_Id : Entity_Id;
4385 Err_Loc : Node_Id := Empty)
4387 Result : Boolean;
4388 begin
4389 Check_Conformance
4390 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc);
4391 end Check_Subtype_Conformant;
4393 ---------------------------
4394 -- Check_Type_Conformant --
4395 ---------------------------
4397 procedure Check_Type_Conformant
4398 (New_Id : Entity_Id;
4399 Old_Id : Entity_Id;
4400 Err_Loc : Node_Id := Empty)
4402 Result : Boolean;
4403 begin
4404 Check_Conformance
4405 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
4406 end Check_Type_Conformant;
4408 ----------------------
4409 -- Conforming_Types --
4410 ----------------------
4412 function Conforming_Types
4413 (T1 : Entity_Id;
4414 T2 : Entity_Id;
4415 Ctype : Conformance_Type;
4416 Get_Inst : Boolean := False) return Boolean
4418 Type_1 : Entity_Id := T1;
4419 Type_2 : Entity_Id := T2;
4420 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
4422 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
4423 -- If neither T1 nor T2 are generic actual types, or if they are in
4424 -- different scopes (e.g. parent and child instances), then verify that
4425 -- the base types are equal. Otherwise T1 and T2 must be on the same
4426 -- subtype chain. The whole purpose of this procedure is to prevent
4427 -- spurious ambiguities in an instantiation that may arise if two
4428 -- distinct generic types are instantiated with the same actual.
4430 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
4431 -- An access parameter can designate an incomplete type. If the
4432 -- incomplete type is the limited view of a type from a limited_
4433 -- with_clause, check whether the non-limited view is available. If
4434 -- it is a (non-limited) incomplete type, get the full view.
4436 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
4437 -- Returns True if and only if either T1 denotes a limited view of T2
4438 -- or T2 denotes a limited view of T1. This can arise when the limited
4439 -- with view of a type is used in a subprogram declaration and the
4440 -- subprogram body is in the scope of a regular with clause for the
4441 -- same unit. In such a case, the two type entities can be considered
4442 -- identical for purposes of conformance checking.
4444 ----------------------
4445 -- Base_Types_Match --
4446 ----------------------
4448 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
4449 begin
4450 if T1 = T2 then
4451 return True;
4453 elsif Base_Type (T1) = Base_Type (T2) then
4455 -- The following is too permissive. A more precise test should
4456 -- check that the generic actual is an ancestor subtype of the
4457 -- other ???.
4459 return not Is_Generic_Actual_Type (T1)
4460 or else not Is_Generic_Actual_Type (T2)
4461 or else Scope (T1) /= Scope (T2);
4463 else
4464 return False;
4465 end if;
4466 end Base_Types_Match;
4468 --------------------------
4469 -- Find_Designated_Type --
4470 --------------------------
4472 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
4473 Desig : Entity_Id;
4475 begin
4476 Desig := Directly_Designated_Type (T);
4478 if Ekind (Desig) = E_Incomplete_Type then
4480 -- If regular incomplete type, get full view if available
4482 if Present (Full_View (Desig)) then
4483 Desig := Full_View (Desig);
4485 -- If limited view of a type, get non-limited view if available,
4486 -- and check again for a regular incomplete type.
4488 elsif Present (Non_Limited_View (Desig)) then
4489 Desig := Get_Full_View (Non_Limited_View (Desig));
4490 end if;
4491 end if;
4493 return Desig;
4494 end Find_Designated_Type;
4496 -------------------------------
4497 -- Matches_Limited_With_View --
4498 -------------------------------
4500 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
4501 begin
4502 -- In some cases a type imported through a limited_with clause, and
4503 -- its nonlimited view are both visible, for example in an anonymous
4504 -- access-to-class-wide type in a formal. Both entities designate the
4505 -- same type.
4507 if From_With_Type (T1)
4508 and then T2 = Available_View (T1)
4509 then
4510 return True;
4512 elsif From_With_Type (T2)
4513 and then T1 = Available_View (T2)
4514 then
4515 return True;
4517 else
4518 return False;
4519 end if;
4520 end Matches_Limited_With_View;
4522 -- Start of processing for Conforming_Types
4524 begin
4525 -- The context is an instance association for a formal
4526 -- access-to-subprogram type; the formal parameter types require
4527 -- mapping because they may denote other formal parameters of the
4528 -- generic unit.
4530 if Get_Inst then
4531 Type_1 := Get_Instance_Of (T1);
4532 Type_2 := Get_Instance_Of (T2);
4533 end if;
4535 -- If one of the types is a view of the other introduced by a limited
4536 -- with clause, treat these as conforming for all purposes.
4538 if Matches_Limited_With_View (T1, T2) then
4539 return True;
4541 elsif Base_Types_Match (Type_1, Type_2) then
4542 return Ctype <= Mode_Conformant
4543 or else Subtypes_Statically_Match (Type_1, Type_2);
4545 elsif Is_Incomplete_Or_Private_Type (Type_1)
4546 and then Present (Full_View (Type_1))
4547 and then Base_Types_Match (Full_View (Type_1), Type_2)
4548 then
4549 return Ctype <= Mode_Conformant
4550 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
4552 elsif Ekind (Type_2) = E_Incomplete_Type
4553 and then Present (Full_View (Type_2))
4554 and then Base_Types_Match (Type_1, Full_View (Type_2))
4555 then
4556 return Ctype <= Mode_Conformant
4557 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4559 elsif Is_Private_Type (Type_2)
4560 and then In_Instance
4561 and then Present (Full_View (Type_2))
4562 and then Base_Types_Match (Type_1, Full_View (Type_2))
4563 then
4564 return Ctype <= Mode_Conformant
4565 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4566 end if;
4568 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
4569 -- treated recursively because they carry a signature.
4571 Are_Anonymous_Access_To_Subprogram_Types :=
4572 Ekind (Type_1) = Ekind (Type_2)
4573 and then
4574 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
4575 or else
4576 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
4578 -- Test anonymous access type case. For this case, static subtype
4579 -- matching is required for mode conformance (RM 6.3.1(15)). We check
4580 -- the base types because we may have built internal subtype entities
4581 -- to handle null-excluding types (see Process_Formals).
4583 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
4584 and then
4585 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
4586 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
4587 then
4588 declare
4589 Desig_1 : Entity_Id;
4590 Desig_2 : Entity_Id;
4592 begin
4593 -- In Ada2005, access constant indicators must match for
4594 -- subtype conformance.
4596 if Ada_Version >= Ada_05
4597 and then Ctype >= Subtype_Conformant
4598 and then
4599 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
4600 then
4601 return False;
4602 end if;
4604 Desig_1 := Find_Designated_Type (Type_1);
4606 Desig_2 := Find_Designated_Type (Type_2);
4608 -- If the context is an instance association for a formal
4609 -- access-to-subprogram type; formal access parameter designated
4610 -- types require mapping because they may denote other formal
4611 -- parameters of the generic unit.
4613 if Get_Inst then
4614 Desig_1 := Get_Instance_Of (Desig_1);
4615 Desig_2 := Get_Instance_Of (Desig_2);
4616 end if;
4618 -- It is possible for a Class_Wide_Type to be introduced for an
4619 -- incomplete type, in which case there is a separate class_ wide
4620 -- type for the full view. The types conform if their Etypes
4621 -- conform, i.e. one may be the full view of the other. This can
4622 -- only happen in the context of an access parameter, other uses
4623 -- of an incomplete Class_Wide_Type are illegal.
4625 if Is_Class_Wide_Type (Desig_1)
4626 and then Is_Class_Wide_Type (Desig_2)
4627 then
4628 return
4629 Conforming_Types
4630 (Etype (Base_Type (Desig_1)),
4631 Etype (Base_Type (Desig_2)), Ctype);
4633 elsif Are_Anonymous_Access_To_Subprogram_Types then
4634 if Ada_Version < Ada_05 then
4635 return Ctype = Type_Conformant
4636 or else
4637 Subtypes_Statically_Match (Desig_1, Desig_2);
4639 -- We must check the conformance of the signatures themselves
4641 else
4642 declare
4643 Conformant : Boolean;
4644 begin
4645 Check_Conformance
4646 (Desig_1, Desig_2, Ctype, False, Conformant);
4647 return Conformant;
4648 end;
4649 end if;
4651 else
4652 return Base_Type (Desig_1) = Base_Type (Desig_2)
4653 and then (Ctype = Type_Conformant
4654 or else
4655 Subtypes_Statically_Match (Desig_1, Desig_2));
4656 end if;
4657 end;
4659 -- Otherwise definitely no match
4661 else
4662 if ((Ekind (Type_1) = E_Anonymous_Access_Type
4663 and then Is_Access_Type (Type_2))
4664 or else (Ekind (Type_2) = E_Anonymous_Access_Type
4665 and then Is_Access_Type (Type_1)))
4666 and then
4667 Conforming_Types
4668 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
4669 then
4670 May_Hide_Profile := True;
4671 end if;
4673 return False;
4674 end if;
4675 end Conforming_Types;
4677 --------------------------
4678 -- Create_Extra_Formals --
4679 --------------------------
4681 procedure Create_Extra_Formals (E : Entity_Id) is
4682 Formal : Entity_Id;
4683 First_Extra : Entity_Id := Empty;
4684 Last_Extra : Entity_Id;
4685 Formal_Type : Entity_Id;
4686 P_Formal : Entity_Id := Empty;
4688 function Add_Extra_Formal
4689 (Assoc_Entity : Entity_Id;
4690 Typ : Entity_Id;
4691 Scope : Entity_Id;
4692 Suffix : String) return Entity_Id;
4693 -- Add an extra formal to the current list of formals and extra formals.
4694 -- The extra formal is added to the end of the list of extra formals,
4695 -- and also returned as the result. These formals are always of mode IN.
4696 -- The new formal has the type Typ, is declared in Scope, and its name
4697 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
4699 ----------------------
4700 -- Add_Extra_Formal --
4701 ----------------------
4703 function Add_Extra_Formal
4704 (Assoc_Entity : Entity_Id;
4705 Typ : Entity_Id;
4706 Scope : Entity_Id;
4707 Suffix : String) return Entity_Id
4709 EF : constant Entity_Id :=
4710 Make_Defining_Identifier (Sloc (Assoc_Entity),
4711 Chars => New_External_Name (Chars (Assoc_Entity),
4712 Suffix => Suffix));
4714 begin
4715 -- A little optimization. Never generate an extra formal for the
4716 -- _init operand of an initialization procedure, since it could
4717 -- never be used.
4719 if Chars (Formal) = Name_uInit then
4720 return Empty;
4721 end if;
4723 Set_Ekind (EF, E_In_Parameter);
4724 Set_Actual_Subtype (EF, Typ);
4725 Set_Etype (EF, Typ);
4726 Set_Scope (EF, Scope);
4727 Set_Mechanism (EF, Default_Mechanism);
4728 Set_Formal_Validity (EF);
4730 if No (First_Extra) then
4731 First_Extra := EF;
4732 Set_Extra_Formals (Scope, First_Extra);
4733 end if;
4735 if Present (Last_Extra) then
4736 Set_Extra_Formal (Last_Extra, EF);
4737 end if;
4739 Last_Extra := EF;
4741 return EF;
4742 end Add_Extra_Formal;
4744 -- Start of processing for Create_Extra_Formals
4746 begin
4747 -- We never generate extra formals if expansion is not active
4748 -- because we don't need them unless we are generating code.
4750 if not Expander_Active then
4751 return;
4752 end if;
4754 -- If this is a derived subprogram then the subtypes of the parent
4755 -- subprogram's formal parameters will be used to to determine the need
4756 -- for extra formals.
4758 if Is_Overloadable (E) and then Present (Alias (E)) then
4759 P_Formal := First_Formal (Alias (E));
4760 end if;
4762 Last_Extra := Empty;
4763 Formal := First_Formal (E);
4764 while Present (Formal) loop
4765 Last_Extra := Formal;
4766 Next_Formal (Formal);
4767 end loop;
4769 -- If Extra_formals were already created, don't do it again. This
4770 -- situation may arise for subprogram types created as part of
4771 -- dispatching calls (see Expand_Dispatching_Call)
4773 if Present (Last_Extra) and then
4774 Present (Extra_Formal (Last_Extra))
4775 then
4776 return;
4777 end if;
4779 -- If the subprogram is a predefined dispatching subprogram then don't
4780 -- generate any extra constrained or accessibility level formals. In
4781 -- general we suppress these for internal subprograms (by not calling
4782 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
4783 -- generated stream attributes do get passed through because extra
4784 -- build-in-place formals are needed in some cases (limited 'Input).
4786 if Is_Predefined_Dispatching_Operation (E) then
4787 goto Test_For_BIP_Extras;
4788 end if;
4790 Formal := First_Formal (E);
4791 while Present (Formal) loop
4793 -- Create extra formal for supporting the attribute 'Constrained.
4794 -- The case of a private type view without discriminants also
4795 -- requires the extra formal if the underlying type has defaulted
4796 -- discriminants.
4798 if Ekind (Formal) /= E_In_Parameter then
4799 if Present (P_Formal) then
4800 Formal_Type := Etype (P_Formal);
4801 else
4802 Formal_Type := Etype (Formal);
4803 end if;
4805 -- Do not produce extra formals for Unchecked_Union parameters.
4806 -- Jump directly to the end of the loop.
4808 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
4809 goto Skip_Extra_Formal_Generation;
4810 end if;
4812 if not Has_Discriminants (Formal_Type)
4813 and then Ekind (Formal_Type) in Private_Kind
4814 and then Present (Underlying_Type (Formal_Type))
4815 then
4816 Formal_Type := Underlying_Type (Formal_Type);
4817 end if;
4819 if Has_Discriminants (Formal_Type)
4820 and then not Is_Constrained (Formal_Type)
4821 and then not Is_Indefinite_Subtype (Formal_Type)
4822 then
4823 Set_Extra_Constrained
4824 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "F"));
4825 end if;
4826 end if;
4828 -- Create extra formal for supporting accessibility checking. This
4829 -- is done for both anonymous access formals and formals of named
4830 -- access types that are marked as controlling formals. The latter
4831 -- case can occur when Expand_Dispatching_Call creates a subprogram
4832 -- type and substitutes the types of access-to-class-wide actuals
4833 -- for the anonymous access-to-specific-type of controlling formals.
4834 -- Base_Type is applied because in cases where there is a null
4835 -- exclusion the formal may have an access subtype.
4837 -- This is suppressed if we specifically suppress accessibility
4838 -- checks at the package level for either the subprogram, or the
4839 -- package in which it resides. However, we do not suppress it
4840 -- simply if the scope has accessibility checks suppressed, since
4841 -- this could cause trouble when clients are compiled with a
4842 -- different suppression setting. The explicit checks at the
4843 -- package level are safe from this point of view.
4845 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
4846 or else (Is_Controlling_Formal (Formal)
4847 and then Is_Access_Type (Base_Type (Etype (Formal)))))
4848 and then not
4849 (Explicit_Suppress (E, Accessibility_Check)
4850 or else
4851 Explicit_Suppress (Scope (E), Accessibility_Check))
4852 and then
4853 (No (P_Formal)
4854 or else Present (Extra_Accessibility (P_Formal)))
4855 then
4856 -- Temporary kludge: for now we avoid creating the extra formal
4857 -- for access parameters of protected operations because of
4858 -- problem with the case of internal protected calls. ???
4860 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
4861 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
4862 then
4863 Set_Extra_Accessibility
4864 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "F"));
4865 end if;
4866 end if;
4868 -- This label is required when skipping extra formal generation for
4869 -- Unchecked_Union parameters.
4871 <<Skip_Extra_Formal_Generation>>
4873 if Present (P_Formal) then
4874 Next_Formal (P_Formal);
4875 end if;
4877 Next_Formal (Formal);
4878 end loop;
4880 <<Test_For_BIP_Extras>>
4882 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
4883 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
4885 if Ada_Version >= Ada_05 and then Is_Build_In_Place_Function (E) then
4886 declare
4887 Result_Subt : constant Entity_Id := Etype (E);
4889 Discard : Entity_Id;
4890 pragma Warnings (Off, Discard);
4892 begin
4893 -- In the case of functions with unconstrained result subtypes,
4894 -- add a 3-state formal indicating whether the return object is
4895 -- allocated by the caller (0), or should be allocated by the
4896 -- callee on the secondary stack (1) or in the global heap (2).
4897 -- For the moment we just use Natural for the type of this formal.
4898 -- Note that this formal isn't usually needed in the case where
4899 -- the result subtype is constrained, but it is needed when the
4900 -- function has a tagged result, because generally such functions
4901 -- can be called in a dispatching context and such calls must be
4902 -- handled like calls to a class-wide function.
4904 if not Is_Constrained (Result_Subt)
4905 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
4906 then
4907 Discard :=
4908 Add_Extra_Formal
4909 (E, Standard_Natural,
4910 E, BIP_Formal_Suffix (BIP_Alloc_Form));
4911 end if;
4913 -- In the case of functions whose result type has controlled
4914 -- parts, we have an extra formal of type
4915 -- System.Finalization_Implementation.Finalizable_Ptr_Ptr. That
4916 -- is, we are passing a pointer to a finalization list (which is
4917 -- itself a pointer). This extra formal is then passed along to
4918 -- Move_Final_List in case of successful completion of a return
4919 -- statement. We cannot pass an 'in out' parameter, because we
4920 -- need to update the finalization list during an abort-deferred
4921 -- region, rather than using copy-back after the function
4922 -- returns. This is true even if we are able to get away with
4923 -- having 'in out' parameters, which are normally illegal for
4924 -- functions. This formal is also needed when the function has
4925 -- a tagged result, because generally such functions can be called
4926 -- in a dispatching context and such calls must be handled like
4927 -- calls to class-wide functions.
4929 if Controlled_Type (Result_Subt)
4930 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
4931 then
4932 Discard :=
4933 Add_Extra_Formal
4934 (E, RTE (RE_Finalizable_Ptr_Ptr),
4935 E, BIP_Formal_Suffix (BIP_Final_List));
4936 end if;
4938 -- If the result type contains tasks, we have two extra formals:
4939 -- the master of the tasks to be created, and the caller's
4940 -- activation chain.
4942 if Has_Task (Result_Subt) then
4943 Discard :=
4944 Add_Extra_Formal
4945 (E, RTE (RE_Master_Id),
4946 E, BIP_Formal_Suffix (BIP_Master));
4947 Discard :=
4948 Add_Extra_Formal
4949 (E, RTE (RE_Activation_Chain_Access),
4950 E, BIP_Formal_Suffix (BIP_Activation_Chain));
4951 end if;
4953 -- All build-in-place functions get an extra formal that will be
4954 -- passed the address of the return object within the caller.
4956 declare
4957 Formal_Type : constant Entity_Id :=
4958 Create_Itype
4959 (E_Anonymous_Access_Type, E,
4960 Scope_Id => Scope (E));
4961 begin
4962 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
4963 Set_Etype (Formal_Type, Formal_Type);
4964 Init_Size_Align (Formal_Type);
4965 Set_Depends_On_Private
4966 (Formal_Type, Has_Private_Component (Formal_Type));
4967 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
4968 Set_Is_Access_Constant (Formal_Type, False);
4970 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
4971 -- the designated type comes from the limited view (for
4972 -- back-end purposes).
4974 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
4976 Layout_Type (Formal_Type);
4978 Discard :=
4979 Add_Extra_Formal
4980 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
4981 end;
4982 end;
4983 end if;
4984 end Create_Extra_Formals;
4986 -----------------------------
4987 -- Enter_Overloaded_Entity --
4988 -----------------------------
4990 procedure Enter_Overloaded_Entity (S : Entity_Id) is
4991 E : Entity_Id := Current_Entity_In_Scope (S);
4992 C_E : Entity_Id := Current_Entity (S);
4994 begin
4995 if Present (E) then
4996 Set_Has_Homonym (E);
4997 Set_Has_Homonym (S);
4998 end if;
5000 Set_Is_Immediately_Visible (S);
5001 Set_Scope (S, Current_Scope);
5003 -- Chain new entity if front of homonym in current scope, so that
5004 -- homonyms are contiguous.
5006 if Present (E)
5007 and then E /= C_E
5008 then
5009 while Homonym (C_E) /= E loop
5010 C_E := Homonym (C_E);
5011 end loop;
5013 Set_Homonym (C_E, S);
5015 else
5016 E := C_E;
5017 Set_Current_Entity (S);
5018 end if;
5020 Set_Homonym (S, E);
5022 Append_Entity (S, Current_Scope);
5023 Set_Public_Status (S);
5025 if Debug_Flag_E then
5026 Write_Str ("New overloaded entity chain: ");
5027 Write_Name (Chars (S));
5029 E := S;
5030 while Present (E) loop
5031 Write_Str (" "); Write_Int (Int (E));
5032 E := Homonym (E);
5033 end loop;
5035 Write_Eol;
5036 end if;
5038 -- Generate warning for hiding
5040 if Warn_On_Hiding
5041 and then Comes_From_Source (S)
5042 and then In_Extended_Main_Source_Unit (S)
5043 then
5044 E := S;
5045 loop
5046 E := Homonym (E);
5047 exit when No (E);
5049 -- Warn unless genuine overloading
5051 if (not Is_Overloadable (E) or else Subtype_Conformant (E, S))
5052 and then (Is_Immediately_Visible (E)
5053 or else
5054 Is_Potentially_Use_Visible (S))
5055 then
5056 Error_Msg_Sloc := Sloc (E);
5057 Error_Msg_N ("declaration of & hides one#?", S);
5058 end if;
5059 end loop;
5060 end if;
5061 end Enter_Overloaded_Entity;
5063 -----------------------------
5064 -- Find_Corresponding_Spec --
5065 -----------------------------
5067 function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is
5068 Spec : constant Node_Id := Specification (N);
5069 Designator : constant Entity_Id := Defining_Entity (Spec);
5071 E : Entity_Id;
5073 begin
5074 E := Current_Entity (Designator);
5075 while Present (E) loop
5077 -- We are looking for a matching spec. It must have the same scope,
5078 -- and the same name, and either be type conformant, or be the case
5079 -- of a library procedure spec and its body (which belong to one
5080 -- another regardless of whether they are type conformant or not).
5082 if Scope (E) = Current_Scope then
5083 if Current_Scope = Standard_Standard
5084 or else (Ekind (E) = Ekind (Designator)
5085 and then Type_Conformant (E, Designator))
5086 then
5087 -- Within an instantiation, we know that spec and body are
5088 -- subtype conformant, because they were subtype conformant
5089 -- in the generic. We choose the subtype-conformant entity
5090 -- here as well, to resolve spurious ambiguities in the
5091 -- instance that were not present in the generic (i.e. when
5092 -- two different types are given the same actual). If we are
5093 -- looking for a spec to match a body, full conformance is
5094 -- expected.
5096 if In_Instance then
5097 Set_Convention (Designator, Convention (E));
5099 if Nkind (N) = N_Subprogram_Body
5100 and then Present (Homonym (E))
5101 and then not Fully_Conformant (E, Designator)
5102 then
5103 goto Next_Entity;
5105 elsif not Subtype_Conformant (E, Designator) then
5106 goto Next_Entity;
5107 end if;
5108 end if;
5110 if not Has_Completion (E) then
5112 if Nkind (N) /= N_Subprogram_Body_Stub then
5113 Set_Corresponding_Spec (N, E);
5114 end if;
5116 Set_Has_Completion (E);
5117 return E;
5119 elsif Nkind (Parent (N)) = N_Subunit then
5121 -- If this is the proper body of a subunit, the completion
5122 -- flag is set when analyzing the stub.
5124 return E;
5126 -- If body already exists, this is an error unless the
5127 -- previous declaration is the implicit declaration of
5128 -- a derived subprogram, or this is a spurious overloading
5129 -- in an instance.
5131 elsif No (Alias (E))
5132 and then not Is_Intrinsic_Subprogram (E)
5133 and then not In_Instance
5134 then
5135 Error_Msg_Sloc := Sloc (E);
5136 if Is_Imported (E) then
5137 Error_Msg_NE
5138 ("body not allowed for imported subprogram & declared#",
5139 N, E);
5140 else
5141 Error_Msg_NE ("duplicate body for & declared#", N, E);
5142 end if;
5143 end if;
5145 elsif Is_Child_Unit (E)
5146 and then
5147 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
5148 and then
5149 Nkind (Parent (Unit_Declaration_Node (Designator))) =
5150 N_Compilation_Unit
5151 then
5152 -- Child units cannot be overloaded, so a conformance mismatch
5153 -- between body and a previous spec is an error.
5155 Error_Msg_N
5156 ("body of child unit does not match previous declaration", N);
5157 end if;
5158 end if;
5160 <<Next_Entity>>
5161 E := Homonym (E);
5162 end loop;
5164 -- On exit, we know that no previous declaration of subprogram exists
5166 return Empty;
5167 end Find_Corresponding_Spec;
5169 ----------------------
5170 -- Fully_Conformant --
5171 ----------------------
5173 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5174 Result : Boolean;
5175 begin
5176 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
5177 return Result;
5178 end Fully_Conformant;
5180 ----------------------------------
5181 -- Fully_Conformant_Expressions --
5182 ----------------------------------
5184 function Fully_Conformant_Expressions
5185 (Given_E1 : Node_Id;
5186 Given_E2 : Node_Id) return Boolean
5188 E1 : constant Node_Id := Original_Node (Given_E1);
5189 E2 : constant Node_Id := Original_Node (Given_E2);
5190 -- We always test conformance on original nodes, since it is possible
5191 -- for analysis and/or expansion to make things look as though they
5192 -- conform when they do not, e.g. by converting 1+2 into 3.
5194 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
5195 renames Fully_Conformant_Expressions;
5197 function FCL (L1, L2 : List_Id) return Boolean;
5198 -- Compare elements of two lists for conformance. Elements have to
5199 -- be conformant, and actuals inserted as default parameters do not
5200 -- match explicit actuals with the same value.
5202 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
5203 -- Compare an operator node with a function call
5205 ---------
5206 -- FCL --
5207 ---------
5209 function FCL (L1, L2 : List_Id) return Boolean is
5210 N1, N2 : Node_Id;
5212 begin
5213 if L1 = No_List then
5214 N1 := Empty;
5215 else
5216 N1 := First (L1);
5217 end if;
5219 if L2 = No_List then
5220 N2 := Empty;
5221 else
5222 N2 := First (L2);
5223 end if;
5225 -- Compare two lists, skipping rewrite insertions (we want to
5226 -- compare the original trees, not the expanded versions!)
5228 loop
5229 if Is_Rewrite_Insertion (N1) then
5230 Next (N1);
5231 elsif Is_Rewrite_Insertion (N2) then
5232 Next (N2);
5233 elsif No (N1) then
5234 return No (N2);
5235 elsif No (N2) then
5236 return False;
5237 elsif not FCE (N1, N2) then
5238 return False;
5239 else
5240 Next (N1);
5241 Next (N2);
5242 end if;
5243 end loop;
5244 end FCL;
5246 ---------
5247 -- FCO --
5248 ---------
5250 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
5251 Actuals : constant List_Id := Parameter_Associations (Call_Node);
5252 Act : Node_Id;
5254 begin
5255 if No (Actuals)
5256 or else Entity (Op_Node) /= Entity (Name (Call_Node))
5257 then
5258 return False;
5260 else
5261 Act := First (Actuals);
5263 if Nkind (Op_Node) in N_Binary_Op then
5265 if not FCE (Left_Opnd (Op_Node), Act) then
5266 return False;
5267 end if;
5269 Next (Act);
5270 end if;
5272 return Present (Act)
5273 and then FCE (Right_Opnd (Op_Node), Act)
5274 and then No (Next (Act));
5275 end if;
5276 end FCO;
5278 -- Start of processing for Fully_Conformant_Expressions
5280 begin
5281 -- Non-conformant if paren count does not match. Note: if some idiot
5282 -- complains that we don't do this right for more than 3 levels of
5283 -- parentheses, they will be treated with the respect they deserve!
5285 if Paren_Count (E1) /= Paren_Count (E2) then
5286 return False;
5288 -- If same entities are referenced, then they are conformant even if
5289 -- they have different forms (RM 8.3.1(19-20)).
5291 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
5292 if Present (Entity (E1)) then
5293 return Entity (E1) = Entity (E2)
5294 or else (Chars (Entity (E1)) = Chars (Entity (E2))
5295 and then Ekind (Entity (E1)) = E_Discriminant
5296 and then Ekind (Entity (E2)) = E_In_Parameter);
5298 elsif Nkind (E1) = N_Expanded_Name
5299 and then Nkind (E2) = N_Expanded_Name
5300 and then Nkind (Selector_Name (E1)) = N_Character_Literal
5301 and then Nkind (Selector_Name (E2)) = N_Character_Literal
5302 then
5303 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
5305 else
5306 -- Identifiers in component associations don't always have
5307 -- entities, but their names must conform.
5309 return Nkind (E1) = N_Identifier
5310 and then Nkind (E2) = N_Identifier
5311 and then Chars (E1) = Chars (E2);
5312 end if;
5314 elsif Nkind (E1) = N_Character_Literal
5315 and then Nkind (E2) = N_Expanded_Name
5316 then
5317 return Nkind (Selector_Name (E2)) = N_Character_Literal
5318 and then Chars (E1) = Chars (Selector_Name (E2));
5320 elsif Nkind (E2) = N_Character_Literal
5321 and then Nkind (E1) = N_Expanded_Name
5322 then
5323 return Nkind (Selector_Name (E1)) = N_Character_Literal
5324 and then Chars (E2) = Chars (Selector_Name (E1));
5326 elsif Nkind (E1) in N_Op
5327 and then Nkind (E2) = N_Function_Call
5328 then
5329 return FCO (E1, E2);
5331 elsif Nkind (E2) in N_Op
5332 and then Nkind (E1) = N_Function_Call
5333 then
5334 return FCO (E2, E1);
5336 -- Otherwise we must have the same syntactic entity
5338 elsif Nkind (E1) /= Nkind (E2) then
5339 return False;
5341 -- At this point, we specialize by node type
5343 else
5344 case Nkind (E1) is
5346 when N_Aggregate =>
5347 return
5348 FCL (Expressions (E1), Expressions (E2))
5349 and then FCL (Component_Associations (E1),
5350 Component_Associations (E2));
5352 when N_Allocator =>
5353 if Nkind (Expression (E1)) = N_Qualified_Expression
5354 or else
5355 Nkind (Expression (E2)) = N_Qualified_Expression
5356 then
5357 return FCE (Expression (E1), Expression (E2));
5359 -- Check that the subtype marks and any constraints
5360 -- are conformant
5362 else
5363 declare
5364 Indic1 : constant Node_Id := Expression (E1);
5365 Indic2 : constant Node_Id := Expression (E2);
5366 Elt1 : Node_Id;
5367 Elt2 : Node_Id;
5369 begin
5370 if Nkind (Indic1) /= N_Subtype_Indication then
5371 return
5372 Nkind (Indic2) /= N_Subtype_Indication
5373 and then Entity (Indic1) = Entity (Indic2);
5375 elsif Nkind (Indic2) /= N_Subtype_Indication then
5376 return
5377 Nkind (Indic1) /= N_Subtype_Indication
5378 and then Entity (Indic1) = Entity (Indic2);
5380 else
5381 if Entity (Subtype_Mark (Indic1)) /=
5382 Entity (Subtype_Mark (Indic2))
5383 then
5384 return False;
5385 end if;
5387 Elt1 := First (Constraints (Constraint (Indic1)));
5388 Elt2 := First (Constraints (Constraint (Indic2)));
5390 while Present (Elt1) and then Present (Elt2) loop
5391 if not FCE (Elt1, Elt2) then
5392 return False;
5393 end if;
5395 Next (Elt1);
5396 Next (Elt2);
5397 end loop;
5399 return True;
5400 end if;
5401 end;
5402 end if;
5404 when N_Attribute_Reference =>
5405 return
5406 Attribute_Name (E1) = Attribute_Name (E2)
5407 and then FCL (Expressions (E1), Expressions (E2));
5409 when N_Binary_Op =>
5410 return
5411 Entity (E1) = Entity (E2)
5412 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
5413 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5415 when N_And_Then | N_Or_Else | N_Membership_Test =>
5416 return
5417 FCE (Left_Opnd (E1), Left_Opnd (E2))
5418 and then
5419 FCE (Right_Opnd (E1), Right_Opnd (E2));
5421 when N_Character_Literal =>
5422 return
5423 Char_Literal_Value (E1) = Char_Literal_Value (E2);
5425 when N_Component_Association =>
5426 return
5427 FCL (Choices (E1), Choices (E2))
5428 and then FCE (Expression (E1), Expression (E2));
5430 when N_Conditional_Expression =>
5431 return
5432 FCL (Expressions (E1), Expressions (E2));
5434 when N_Explicit_Dereference =>
5435 return
5436 FCE (Prefix (E1), Prefix (E2));
5438 when N_Extension_Aggregate =>
5439 return
5440 FCL (Expressions (E1), Expressions (E2))
5441 and then Null_Record_Present (E1) =
5442 Null_Record_Present (E2)
5443 and then FCL (Component_Associations (E1),
5444 Component_Associations (E2));
5446 when N_Function_Call =>
5447 return
5448 FCE (Name (E1), Name (E2))
5449 and then FCL (Parameter_Associations (E1),
5450 Parameter_Associations (E2));
5452 when N_Indexed_Component =>
5453 return
5454 FCE (Prefix (E1), Prefix (E2))
5455 and then FCL (Expressions (E1), Expressions (E2));
5457 when N_Integer_Literal =>
5458 return (Intval (E1) = Intval (E2));
5460 when N_Null =>
5461 return True;
5463 when N_Operator_Symbol =>
5464 return
5465 Chars (E1) = Chars (E2);
5467 when N_Others_Choice =>
5468 return True;
5470 when N_Parameter_Association =>
5471 return
5472 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
5473 and then FCE (Explicit_Actual_Parameter (E1),
5474 Explicit_Actual_Parameter (E2));
5476 when N_Qualified_Expression =>
5477 return
5478 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5479 and then FCE (Expression (E1), Expression (E2));
5481 when N_Range =>
5482 return
5483 FCE (Low_Bound (E1), Low_Bound (E2))
5484 and then FCE (High_Bound (E1), High_Bound (E2));
5486 when N_Real_Literal =>
5487 return (Realval (E1) = Realval (E2));
5489 when N_Selected_Component =>
5490 return
5491 FCE (Prefix (E1), Prefix (E2))
5492 and then FCE (Selector_Name (E1), Selector_Name (E2));
5494 when N_Slice =>
5495 return
5496 FCE (Prefix (E1), Prefix (E2))
5497 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
5499 when N_String_Literal =>
5500 declare
5501 S1 : constant String_Id := Strval (E1);
5502 S2 : constant String_Id := Strval (E2);
5503 L1 : constant Nat := String_Length (S1);
5504 L2 : constant Nat := String_Length (S2);
5506 begin
5507 if L1 /= L2 then
5508 return False;
5510 else
5511 for J in 1 .. L1 loop
5512 if Get_String_Char (S1, J) /=
5513 Get_String_Char (S2, J)
5514 then
5515 return False;
5516 end if;
5517 end loop;
5519 return True;
5520 end if;
5521 end;
5523 when N_Type_Conversion =>
5524 return
5525 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5526 and then FCE (Expression (E1), Expression (E2));
5528 when N_Unary_Op =>
5529 return
5530 Entity (E1) = Entity (E2)
5531 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5533 when N_Unchecked_Type_Conversion =>
5534 return
5535 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5536 and then FCE (Expression (E1), Expression (E2));
5538 -- All other node types cannot appear in this context. Strictly
5539 -- we should raise a fatal internal error. Instead we just ignore
5540 -- the nodes. This means that if anyone makes a mistake in the
5541 -- expander and mucks an expression tree irretrievably, the
5542 -- result will be a failure to detect a (probably very obscure)
5543 -- case of non-conformance, which is better than bombing on some
5544 -- case where two expressions do in fact conform.
5546 when others =>
5547 return True;
5549 end case;
5550 end if;
5551 end Fully_Conformant_Expressions;
5553 ----------------------------------------
5554 -- Fully_Conformant_Discrete_Subtypes --
5555 ----------------------------------------
5557 function Fully_Conformant_Discrete_Subtypes
5558 (Given_S1 : Node_Id;
5559 Given_S2 : Node_Id) return Boolean
5561 S1 : constant Node_Id := Original_Node (Given_S1);
5562 S2 : constant Node_Id := Original_Node (Given_S2);
5564 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
5565 -- Special-case for a bound given by a discriminant, which in the body
5566 -- is replaced with the discriminal of the enclosing type.
5568 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
5569 -- Check both bounds
5571 -----------------------
5572 -- Conforming_Bounds --
5573 -----------------------
5575 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
5576 begin
5577 if Is_Entity_Name (B1)
5578 and then Is_Entity_Name (B2)
5579 and then Ekind (Entity (B1)) = E_Discriminant
5580 then
5581 return Chars (B1) = Chars (B2);
5583 else
5584 return Fully_Conformant_Expressions (B1, B2);
5585 end if;
5586 end Conforming_Bounds;
5588 -----------------------
5589 -- Conforming_Ranges --
5590 -----------------------
5592 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
5593 begin
5594 return
5595 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
5596 and then
5597 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
5598 end Conforming_Ranges;
5600 -- Start of processing for Fully_Conformant_Discrete_Subtypes
5602 begin
5603 if Nkind (S1) /= Nkind (S2) then
5604 return False;
5606 elsif Is_Entity_Name (S1) then
5607 return Entity (S1) = Entity (S2);
5609 elsif Nkind (S1) = N_Range then
5610 return Conforming_Ranges (S1, S2);
5612 elsif Nkind (S1) = N_Subtype_Indication then
5613 return
5614 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
5615 and then
5616 Conforming_Ranges
5617 (Range_Expression (Constraint (S1)),
5618 Range_Expression (Constraint (S2)));
5619 else
5620 return True;
5621 end if;
5622 end Fully_Conformant_Discrete_Subtypes;
5624 --------------------
5625 -- Install_Entity --
5626 --------------------
5628 procedure Install_Entity (E : Entity_Id) is
5629 Prev : constant Entity_Id := Current_Entity (E);
5630 begin
5631 Set_Is_Immediately_Visible (E);
5632 Set_Current_Entity (E);
5633 Set_Homonym (E, Prev);
5634 end Install_Entity;
5636 ---------------------
5637 -- Install_Formals --
5638 ---------------------
5640 procedure Install_Formals (Id : Entity_Id) is
5641 F : Entity_Id;
5642 begin
5643 F := First_Formal (Id);
5644 while Present (F) loop
5645 Install_Entity (F);
5646 Next_Formal (F);
5647 end loop;
5648 end Install_Formals;
5650 ---------------------------------
5651 -- Is_Non_Overriding_Operation --
5652 ---------------------------------
5654 function Is_Non_Overriding_Operation
5655 (Prev_E : Entity_Id;
5656 New_E : Entity_Id) return Boolean
5658 Formal : Entity_Id;
5659 F_Typ : Entity_Id;
5660 G_Typ : Entity_Id := Empty;
5662 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
5663 -- If F_Type is a derived type associated with a generic actual subtype,
5664 -- then return its Generic_Parent_Type attribute, else return Empty.
5666 function Types_Correspond
5667 (P_Type : Entity_Id;
5668 N_Type : Entity_Id) return Boolean;
5669 -- Returns true if and only if the types (or designated types in the
5670 -- case of anonymous access types) are the same or N_Type is derived
5671 -- directly or indirectly from P_Type.
5673 -----------------------------
5674 -- Get_Generic_Parent_Type --
5675 -----------------------------
5677 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
5678 G_Typ : Entity_Id;
5679 Indic : Node_Id;
5681 begin
5682 if Is_Derived_Type (F_Typ)
5683 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
5684 then
5685 -- The tree must be traversed to determine the parent subtype in
5686 -- the generic unit, which unfortunately isn't always available
5687 -- via semantic attributes. ??? (Note: The use of Original_Node
5688 -- is needed for cases where a full derived type has been
5689 -- rewritten.)
5691 Indic := Subtype_Indication
5692 (Type_Definition (Original_Node (Parent (F_Typ))));
5694 if Nkind (Indic) = N_Subtype_Indication then
5695 G_Typ := Entity (Subtype_Mark (Indic));
5696 else
5697 G_Typ := Entity (Indic);
5698 end if;
5700 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
5701 and then Present (Generic_Parent_Type (Parent (G_Typ)))
5702 then
5703 return Generic_Parent_Type (Parent (G_Typ));
5704 end if;
5705 end if;
5707 return Empty;
5708 end Get_Generic_Parent_Type;
5710 ----------------------
5711 -- Types_Correspond --
5712 ----------------------
5714 function Types_Correspond
5715 (P_Type : Entity_Id;
5716 N_Type : Entity_Id) return Boolean
5718 Prev_Type : Entity_Id := Base_Type (P_Type);
5719 New_Type : Entity_Id := Base_Type (N_Type);
5721 begin
5722 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
5723 Prev_Type := Designated_Type (Prev_Type);
5724 end if;
5726 if Ekind (New_Type) = E_Anonymous_Access_Type then
5727 New_Type := Designated_Type (New_Type);
5728 end if;
5730 if Prev_Type = New_Type then
5731 return True;
5733 elsif not Is_Class_Wide_Type (New_Type) then
5734 while Etype (New_Type) /= New_Type loop
5735 New_Type := Etype (New_Type);
5736 if New_Type = Prev_Type then
5737 return True;
5738 end if;
5739 end loop;
5740 end if;
5741 return False;
5742 end Types_Correspond;
5744 -- Start of processing for Is_Non_Overriding_Operation
5746 begin
5747 -- In the case where both operations are implicit derived subprograms
5748 -- then neither overrides the other. This can only occur in certain
5749 -- obscure cases (e.g., derivation from homographs created in a generic
5750 -- instantiation).
5752 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
5753 return True;
5755 elsif Ekind (Current_Scope) = E_Package
5756 and then Is_Generic_Instance (Current_Scope)
5757 and then In_Private_Part (Current_Scope)
5758 and then Comes_From_Source (New_E)
5759 then
5760 -- We examine the formals and result subtype of the inherited
5761 -- operation, to determine whether their type is derived from (the
5762 -- instance of) a generic type.
5764 Formal := First_Formal (Prev_E);
5766 while Present (Formal) loop
5767 F_Typ := Base_Type (Etype (Formal));
5769 if Ekind (F_Typ) = E_Anonymous_Access_Type then
5770 F_Typ := Designated_Type (F_Typ);
5771 end if;
5773 G_Typ := Get_Generic_Parent_Type (F_Typ);
5775 Next_Formal (Formal);
5776 end loop;
5778 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
5779 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
5780 end if;
5782 if No (G_Typ) then
5783 return False;
5784 end if;
5786 -- If the generic type is a private type, then the original
5787 -- operation was not overriding in the generic, because there was
5788 -- no primitive operation to override.
5790 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
5791 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
5792 N_Formal_Private_Type_Definition
5793 then
5794 return True;
5796 -- The generic parent type is the ancestor of a formal derived
5797 -- type declaration. We need to check whether it has a primitive
5798 -- operation that should be overridden by New_E in the generic.
5800 else
5801 declare
5802 P_Formal : Entity_Id;
5803 N_Formal : Entity_Id;
5804 P_Typ : Entity_Id;
5805 N_Typ : Entity_Id;
5806 P_Prim : Entity_Id;
5807 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
5809 begin
5810 while Present (Prim_Elt) loop
5811 P_Prim := Node (Prim_Elt);
5813 if Chars (P_Prim) = Chars (New_E)
5814 and then Ekind (P_Prim) = Ekind (New_E)
5815 then
5816 P_Formal := First_Formal (P_Prim);
5817 N_Formal := First_Formal (New_E);
5818 while Present (P_Formal) and then Present (N_Formal) loop
5819 P_Typ := Etype (P_Formal);
5820 N_Typ := Etype (N_Formal);
5822 if not Types_Correspond (P_Typ, N_Typ) then
5823 exit;
5824 end if;
5826 Next_Entity (P_Formal);
5827 Next_Entity (N_Formal);
5828 end loop;
5830 -- Found a matching primitive operation belonging to the
5831 -- formal ancestor type, so the new subprogram is
5832 -- overriding.
5834 if No (P_Formal)
5835 and then No (N_Formal)
5836 and then (Ekind (New_E) /= E_Function
5837 or else
5838 Types_Correspond
5839 (Etype (P_Prim), Etype (New_E)))
5840 then
5841 return False;
5842 end if;
5843 end if;
5845 Next_Elmt (Prim_Elt);
5846 end loop;
5848 -- If no match found, then the new subprogram does not
5849 -- override in the generic (nor in the instance).
5851 return True;
5852 end;
5853 end if;
5854 else
5855 return False;
5856 end if;
5857 end Is_Non_Overriding_Operation;
5859 ------------------------------
5860 -- Make_Inequality_Operator --
5861 ------------------------------
5863 -- S is the defining identifier of an equality operator. We build a
5864 -- subprogram declaration with the right signature. This operation is
5865 -- intrinsic, because it is always expanded as the negation of the
5866 -- call to the equality function.
5868 procedure Make_Inequality_Operator (S : Entity_Id) is
5869 Loc : constant Source_Ptr := Sloc (S);
5870 Decl : Node_Id;
5871 Formals : List_Id;
5872 Op_Name : Entity_Id;
5874 FF : constant Entity_Id := First_Formal (S);
5875 NF : constant Entity_Id := Next_Formal (FF);
5877 begin
5878 -- Check that equality was properly defined, ignore call if not
5880 if No (NF) then
5881 return;
5882 end if;
5884 declare
5885 A : constant Entity_Id :=
5886 Make_Defining_Identifier (Sloc (FF),
5887 Chars => Chars (FF));
5889 B : constant Entity_Id :=
5890 Make_Defining_Identifier (Sloc (NF),
5891 Chars => Chars (NF));
5893 begin
5894 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
5896 Formals := New_List (
5897 Make_Parameter_Specification (Loc,
5898 Defining_Identifier => A,
5899 Parameter_Type =>
5900 New_Reference_To (Etype (First_Formal (S)),
5901 Sloc (Etype (First_Formal (S))))),
5903 Make_Parameter_Specification (Loc,
5904 Defining_Identifier => B,
5905 Parameter_Type =>
5906 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
5907 Sloc (Etype (Next_Formal (First_Formal (S)))))));
5909 Decl :=
5910 Make_Subprogram_Declaration (Loc,
5911 Specification =>
5912 Make_Function_Specification (Loc,
5913 Defining_Unit_Name => Op_Name,
5914 Parameter_Specifications => Formals,
5915 Result_Definition =>
5916 New_Reference_To (Standard_Boolean, Loc)));
5918 -- Insert inequality right after equality if it is explicit or after
5919 -- the derived type when implicit. These entities are created only
5920 -- for visibility purposes, and eventually replaced in the course of
5921 -- expansion, so they do not need to be attached to the tree and seen
5922 -- by the back-end. Keeping them internal also avoids spurious
5923 -- freezing problems. The declaration is inserted in the tree for
5924 -- analysis, and removed afterwards. If the equality operator comes
5925 -- from an explicit declaration, attach the inequality immediately
5926 -- after. Else the equality is inherited from a derived type
5927 -- declaration, so insert inequality after that declaration.
5929 if No (Alias (S)) then
5930 Insert_After (Unit_Declaration_Node (S), Decl);
5931 elsif Is_List_Member (Parent (S)) then
5932 Insert_After (Parent (S), Decl);
5933 else
5934 Insert_After (Parent (Etype (First_Formal (S))), Decl);
5935 end if;
5937 Mark_Rewrite_Insertion (Decl);
5938 Set_Is_Intrinsic_Subprogram (Op_Name);
5939 Analyze (Decl);
5940 Remove (Decl);
5941 Set_Has_Completion (Op_Name);
5942 Set_Corresponding_Equality (Op_Name, S);
5943 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
5944 end;
5945 end Make_Inequality_Operator;
5947 ----------------------
5948 -- May_Need_Actuals --
5949 ----------------------
5951 procedure May_Need_Actuals (Fun : Entity_Id) is
5952 F : Entity_Id;
5953 B : Boolean;
5955 begin
5956 F := First_Formal (Fun);
5957 B := True;
5958 while Present (F) loop
5959 if No (Default_Value (F)) then
5960 B := False;
5961 exit;
5962 end if;
5964 Next_Formal (F);
5965 end loop;
5967 Set_Needs_No_Actuals (Fun, B);
5968 end May_Need_Actuals;
5970 ---------------------
5971 -- Mode_Conformant --
5972 ---------------------
5974 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5975 Result : Boolean;
5976 begin
5977 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
5978 return Result;
5979 end Mode_Conformant;
5981 ---------------------------
5982 -- New_Overloaded_Entity --
5983 ---------------------------
5985 procedure New_Overloaded_Entity
5986 (S : Entity_Id;
5987 Derived_Type : Entity_Id := Empty)
5989 Overridden_Subp : Entity_Id := Empty;
5990 -- Set if the current scope has an operation that is type-conformant
5991 -- with S, and becomes hidden by S.
5993 Is_Primitive_Subp : Boolean;
5994 -- Set to True if the new subprogram is primitive
5996 E : Entity_Id;
5997 -- Entity that S overrides
5999 Prev_Vis : Entity_Id := Empty;
6000 -- Predecessor of E in Homonym chain
6002 procedure Check_For_Primitive_Subprogram
6003 (Is_Primitive : out Boolean;
6004 Is_Overriding : Boolean := False);
6005 -- If the subprogram being analyzed is a primitive operation of the type
6006 -- of a formal or result, set the Has_Primitive_Operations flag on the
6007 -- type, and set Is_Primitive to True (otherwise set to False). Set the
6008 -- corresponding flag on the entity itself for later use.
6010 procedure Check_Synchronized_Overriding
6011 (Def_Id : Entity_Id;
6012 First_Hom : Entity_Id;
6013 Overridden_Subp : out Entity_Id);
6014 -- First determine if Def_Id is an entry or a subprogram either defined
6015 -- in the scope of a task or protected type, or is a primitive of such
6016 -- a type. Check whether Def_Id overrides a subprogram of an interface
6017 -- implemented by the synchronized type, return the overridden entity
6018 -- or Empty.
6020 function Is_Private_Declaration (E : Entity_Id) return Boolean;
6021 -- Check that E is declared in the private part of the current package,
6022 -- or in the package body, where it may hide a previous declaration.
6023 -- We can't use In_Private_Part by itself because this flag is also
6024 -- set when freezing entities, so we must examine the place of the
6025 -- declaration in the tree, and recognize wrapper packages as well.
6027 ------------------------------------
6028 -- Check_For_Primitive_Subprogram --
6029 ------------------------------------
6031 procedure Check_For_Primitive_Subprogram
6032 (Is_Primitive : out Boolean;
6033 Is_Overriding : Boolean := False)
6035 Formal : Entity_Id;
6036 F_Typ : Entity_Id;
6037 B_Typ : Entity_Id;
6039 function Visible_Part_Type (T : Entity_Id) return Boolean;
6040 -- Returns true if T is declared in the visible part of
6041 -- the current package scope; otherwise returns false.
6042 -- Assumes that T is declared in a package.
6044 procedure Check_Private_Overriding (T : Entity_Id);
6045 -- Checks that if a primitive abstract subprogram of a visible
6046 -- abstract type is declared in a private part, then it must
6047 -- override an abstract subprogram declared in the visible part.
6048 -- Also checks that if a primitive function with a controlling
6049 -- result is declared in a private part, then it must override
6050 -- a function declared in the visible part.
6052 ------------------------------
6053 -- Check_Private_Overriding --
6054 ------------------------------
6056 procedure Check_Private_Overriding (T : Entity_Id) is
6057 begin
6058 if Ekind (Current_Scope) = E_Package
6059 and then In_Private_Part (Current_Scope)
6060 and then Visible_Part_Type (T)
6061 and then not In_Instance
6062 then
6063 if Is_Abstract_Type (T)
6064 and then Is_Abstract_Subprogram (S)
6065 and then (not Is_Overriding
6066 or else not Is_Abstract_Subprogram (E))
6067 then
6068 Error_Msg_N ("abstract subprograms must be visible "
6069 & "(RM 3.9.3(10))!", S);
6071 elsif Ekind (S) = E_Function
6072 and then Is_Tagged_Type (T)
6073 and then T = Base_Type (Etype (S))
6074 and then not Is_Overriding
6075 then
6076 Error_Msg_N
6077 ("private function with tagged result must"
6078 & " override visible-part function", S);
6079 Error_Msg_N
6080 ("\move subprogram to the visible part"
6081 & " (RM 3.9.3(10))", S);
6082 end if;
6083 end if;
6084 end Check_Private_Overriding;
6086 -----------------------
6087 -- Visible_Part_Type --
6088 -----------------------
6090 function Visible_Part_Type (T : Entity_Id) return Boolean is
6091 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
6092 N : Node_Id;
6094 begin
6095 -- If the entity is a private type, then it must be
6096 -- declared in a visible part.
6098 if Ekind (T) in Private_Kind then
6099 return True;
6100 end if;
6102 -- Otherwise, we traverse the visible part looking for its
6103 -- corresponding declaration. We cannot use the declaration
6104 -- node directly because in the private part the entity of a
6105 -- private type is the one in the full view, which does not
6106 -- indicate that it is the completion of something visible.
6108 N := First (Visible_Declarations (Specification (P)));
6109 while Present (N) loop
6110 if Nkind (N) = N_Full_Type_Declaration
6111 and then Present (Defining_Identifier (N))
6112 and then T = Defining_Identifier (N)
6113 then
6114 return True;
6116 elsif (Nkind (N) = N_Private_Type_Declaration
6117 or else
6118 Nkind (N) = N_Private_Extension_Declaration)
6119 and then Present (Defining_Identifier (N))
6120 and then T = Full_View (Defining_Identifier (N))
6121 then
6122 return True;
6123 end if;
6125 Next (N);
6126 end loop;
6128 return False;
6129 end Visible_Part_Type;
6131 -- Start of processing for Check_For_Primitive_Subprogram
6133 begin
6134 Is_Primitive := False;
6136 if not Comes_From_Source (S) then
6137 null;
6139 -- If subprogram is at library level, it is not primitive operation
6141 elsif Current_Scope = Standard_Standard then
6142 null;
6144 elsif ((Ekind (Current_Scope) = E_Package
6145 or else Ekind (Current_Scope) = E_Generic_Package)
6146 and then not In_Package_Body (Current_Scope))
6147 or else Is_Overriding
6148 then
6149 -- For function, check return type
6151 if Ekind (S) = E_Function then
6152 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
6153 F_Typ := Designated_Type (Etype (S));
6154 else
6155 F_Typ := Etype (S);
6156 end if;
6158 B_Typ := Base_Type (F_Typ);
6160 if Scope (B_Typ) = Current_Scope
6161 and then not Is_Class_Wide_Type (B_Typ)
6162 and then not Is_Generic_Type (B_Typ)
6163 then
6164 Is_Primitive := True;
6165 Set_Has_Primitive_Operations (B_Typ);
6166 Set_Is_Primitive (S);
6167 Check_Private_Overriding (B_Typ);
6168 end if;
6169 end if;
6171 -- For all subprograms, check formals
6173 Formal := First_Formal (S);
6174 while Present (Formal) loop
6175 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
6176 F_Typ := Designated_Type (Etype (Formal));
6177 else
6178 F_Typ := Etype (Formal);
6179 end if;
6181 B_Typ := Base_Type (F_Typ);
6183 if Ekind (B_Typ) = E_Access_Subtype then
6184 B_Typ := Base_Type (B_Typ);
6185 end if;
6187 if Scope (B_Typ) = Current_Scope
6188 and then not Is_Class_Wide_Type (B_Typ)
6189 and then not Is_Generic_Type (B_Typ)
6190 then
6191 Is_Primitive := True;
6192 Set_Is_Primitive (S);
6193 Set_Has_Primitive_Operations (B_Typ);
6194 Check_Private_Overriding (B_Typ);
6195 end if;
6197 Next_Formal (Formal);
6198 end loop;
6199 end if;
6200 end Check_For_Primitive_Subprogram;
6202 -----------------------------------
6203 -- Check_Synchronized_Overriding --
6204 -----------------------------------
6206 procedure Check_Synchronized_Overriding
6207 (Def_Id : Entity_Id;
6208 First_Hom : Entity_Id;
6209 Overridden_Subp : out Entity_Id)
6211 Formal_Typ : Entity_Id;
6212 Ifaces_List : Elist_Id;
6213 In_Scope : Boolean;
6214 Typ : Entity_Id;
6216 begin
6217 Overridden_Subp := Empty;
6219 -- Def_Id must be an entry or a subprogram
6221 if Ekind (Def_Id) /= E_Entry
6222 and then Ekind (Def_Id) /= E_Function
6223 and then Ekind (Def_Id) /= E_Procedure
6224 then
6225 return;
6226 end if;
6228 -- Search for the concurrent declaration since it contains the list
6229 -- of all implemented interfaces. In this case, the subprogram is
6230 -- declared within the scope of a protected or a task type.
6232 if Present (Scope (Def_Id))
6233 and then Is_Concurrent_Type (Scope (Def_Id))
6234 and then not Is_Generic_Actual_Type (Scope (Def_Id))
6235 then
6236 Typ := Scope (Def_Id);
6237 In_Scope := True;
6239 -- The subprogram may be a primitive of a concurrent type
6241 elsif Present (First_Formal (Def_Id)) then
6242 Formal_Typ := Etype (First_Formal (Def_Id));
6244 if Is_Concurrent_Type (Formal_Typ)
6245 and then not Is_Generic_Actual_Type (Formal_Typ)
6246 then
6247 Typ := Formal_Typ;
6248 In_Scope := False;
6250 -- This case occurs when the concurrent type is declared within
6251 -- a generic unit. As a result the corresponding record has been
6252 -- built and used as the type of the first formal, we just have
6253 -- to retrieve the corresponding concurrent type.
6255 elsif Is_Concurrent_Record_Type (Formal_Typ)
6256 and then Present (Corresponding_Concurrent_Type (Formal_Typ))
6257 then
6258 Typ := Corresponding_Concurrent_Type (Formal_Typ);
6259 In_Scope := False;
6261 else
6262 return;
6263 end if;
6264 else
6265 return;
6266 end if;
6268 -- Gather all limited, protected and task interfaces that Typ
6269 -- implements. There is no overriding to check if is an inherited
6270 -- operation in a type derivation on for a generic actual.
6272 if Nkind (Parent (Typ)) /= N_Full_Type_Declaration
6273 and then Nkind (Parent (Def_Id)) /= N_Subtype_Declaration
6274 and then Nkind (Parent (Def_Id)) /= N_Task_Type_Declaration
6275 and then Nkind (Parent (Def_Id)) /= N_Protected_Type_Declaration
6276 then
6277 Collect_Abstract_Interfaces (Typ, Ifaces_List);
6279 if not Is_Empty_Elmt_List (Ifaces_List) then
6280 Overridden_Subp :=
6281 Find_Overridden_Synchronized_Primitive
6282 (Def_Id, First_Hom, Ifaces_List, In_Scope);
6283 end if;
6284 end if;
6285 end Check_Synchronized_Overriding;
6287 ----------------------------
6288 -- Is_Private_Declaration --
6289 ----------------------------
6291 function Is_Private_Declaration (E : Entity_Id) return Boolean is
6292 Priv_Decls : List_Id;
6293 Decl : constant Node_Id := Unit_Declaration_Node (E);
6295 begin
6296 if Is_Package_Or_Generic_Package (Current_Scope)
6297 and then In_Private_Part (Current_Scope)
6298 then
6299 Priv_Decls :=
6300 Private_Declarations (
6301 Specification (Unit_Declaration_Node (Current_Scope)));
6303 return In_Package_Body (Current_Scope)
6304 or else
6305 (Is_List_Member (Decl)
6306 and then List_Containing (Decl) = Priv_Decls)
6307 or else (Nkind (Parent (Decl)) = N_Package_Specification
6308 and then not Is_Compilation_Unit (
6309 Defining_Entity (Parent (Decl)))
6310 and then List_Containing (Parent (Parent (Decl)))
6311 = Priv_Decls);
6312 else
6313 return False;
6314 end if;
6315 end Is_Private_Declaration;
6317 -- Start of processing for New_Overloaded_Entity
6319 begin
6320 -- We need to look for an entity that S may override. This must be a
6321 -- homonym in the current scope, so we look for the first homonym of
6322 -- S in the current scope as the starting point for the search.
6324 E := Current_Entity_In_Scope (S);
6326 -- If there is no homonym then this is definitely not overriding
6328 if No (E) then
6329 Enter_Overloaded_Entity (S);
6330 Check_Dispatching_Operation (S, Empty);
6331 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6333 -- If subprogram has an explicit declaration, check whether it
6334 -- has an overriding indicator.
6336 if Comes_From_Source (S) then
6337 Check_Synchronized_Overriding (S, Homonym (S), Overridden_Subp);
6338 Check_Overriding_Indicator
6339 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6340 end if;
6342 -- If there is a homonym that is not overloadable, then we have an
6343 -- error, except for the special cases checked explicitly below.
6345 elsif not Is_Overloadable (E) then
6347 -- Check for spurious conflict produced by a subprogram that has the
6348 -- same name as that of the enclosing generic package. The conflict
6349 -- occurs within an instance, between the subprogram and the renaming
6350 -- declaration for the package. After the subprogram, the package
6351 -- renaming declaration becomes hidden.
6353 if Ekind (E) = E_Package
6354 and then Present (Renamed_Object (E))
6355 and then Renamed_Object (E) = Current_Scope
6356 and then Nkind (Parent (Renamed_Object (E))) =
6357 N_Package_Specification
6358 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
6359 then
6360 Set_Is_Hidden (E);
6361 Set_Is_Immediately_Visible (E, False);
6362 Enter_Overloaded_Entity (S);
6363 Set_Homonym (S, Homonym (E));
6364 Check_Dispatching_Operation (S, Empty);
6365 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
6367 -- If the subprogram is implicit it is hidden by the previous
6368 -- declaration. However if it is dispatching, it must appear in the
6369 -- dispatch table anyway, because it can be dispatched to even if it
6370 -- cannot be called directly.
6372 elsif Present (Alias (S))
6373 and then not Comes_From_Source (S)
6374 then
6375 Set_Scope (S, Current_Scope);
6377 if Is_Dispatching_Operation (Alias (S)) then
6378 Check_Dispatching_Operation (S, Empty);
6379 end if;
6381 return;
6383 else
6384 Error_Msg_Sloc := Sloc (E);
6386 -- Generate message,with useful additionalwarning if in generic
6388 if Is_Generic_Unit (E) then
6389 Error_Msg_N ("previous generic unit cannot be overloaded", S);
6390 Error_Msg_N ("\& conflicts with declaration#", S);
6391 else
6392 Error_Msg_N ("& conflicts with declaration#", S);
6393 end if;
6395 return;
6396 end if;
6398 -- E exists and is overloadable
6400 else
6401 -- Ada 2005 (AI-251): Derivation of abstract interface primitives
6402 -- need no check against the homonym chain. They are directly added
6403 -- to the list of primitive operations of Derived_Type.
6405 if Ada_Version >= Ada_05
6406 and then Present (Derived_Type)
6407 and then Is_Dispatching_Operation (Alias (S))
6408 and then Present (Find_Dispatching_Type (Alias (S)))
6409 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
6410 and then not Is_Predefined_Dispatching_Operation (Alias (S))
6411 then
6412 goto Add_New_Entity;
6413 end if;
6415 Check_Synchronized_Overriding (S, E, Overridden_Subp);
6417 -- Loop through E and its homonyms to determine if any of them is
6418 -- the candidate for overriding by S.
6420 while Present (E) loop
6422 -- Definitely not interesting if not in the current scope
6424 if Scope (E) /= Current_Scope then
6425 null;
6427 -- Check if we have type conformance
6429 elsif Type_Conformant (E, S) then
6431 -- If the old and new entities have the same profile and one
6432 -- is not the body of the other, then this is an error, unless
6433 -- one of them is implicitly declared.
6435 -- There are some cases when both can be implicit, for example
6436 -- when both a literal and a function that overrides it are
6437 -- inherited in a derivation, or when an inhertited operation
6438 -- of a tagged full type overrides the inherited operation of
6439 -- a private extension. Ada 83 had a special rule for the the
6440 -- literal case. In Ada95, the later implicit operation hides
6441 -- the former, and the literal is always the former. In the
6442 -- odd case where both are derived operations declared at the
6443 -- same point, both operations should be declared, and in that
6444 -- case we bypass the following test and proceed to the next
6445 -- part (this can only occur for certain obscure cases
6446 -- involving homographs in instances and can't occur for
6447 -- dispatching operations ???). Note that the following
6448 -- condition is less than clear. For example, it's not at all
6449 -- clear why there's a test for E_Entry here. ???
6451 if Present (Alias (S))
6452 and then (No (Alias (E))
6453 or else Comes_From_Source (E)
6454 or else Is_Dispatching_Operation (E))
6455 and then
6456 (Ekind (E) = E_Entry
6457 or else Ekind (E) /= E_Enumeration_Literal)
6458 then
6459 -- When an derived operation is overloaded it may be due to
6460 -- the fact that the full view of a private extension
6461 -- re-inherits. It has to be dealt with.
6463 if Is_Package_Or_Generic_Package (Current_Scope)
6464 and then In_Private_Part (Current_Scope)
6465 then
6466 Check_Operation_From_Private_View (S, E);
6467 end if;
6469 -- In any case the implicit operation remains hidden by
6470 -- the existing declaration, which is overriding.
6472 Set_Is_Overriding_Operation (E);
6474 if Comes_From_Source (E) then
6475 Check_Overriding_Indicator (E, S, Is_Primitive => False);
6477 -- Indicate that E overrides the operation from which
6478 -- S is inherited.
6480 if Present (Alias (S)) then
6481 Set_Overridden_Operation (E, Alias (S));
6482 else
6483 Set_Overridden_Operation (E, S);
6484 end if;
6485 end if;
6487 return;
6489 -- Within an instance, the renaming declarations for
6490 -- actual subprograms may become ambiguous, but they do
6491 -- not hide each other.
6493 elsif Ekind (E) /= E_Entry
6494 and then not Comes_From_Source (E)
6495 and then not Is_Generic_Instance (E)
6496 and then (Present (Alias (E))
6497 or else Is_Intrinsic_Subprogram (E))
6498 and then (not In_Instance
6499 or else No (Parent (E))
6500 or else Nkind (Unit_Declaration_Node (E)) /=
6501 N_Subprogram_Renaming_Declaration)
6502 then
6503 -- A subprogram child unit is not allowed to override
6504 -- an inherited subprogram (10.1.1(20)).
6506 if Is_Child_Unit (S) then
6507 Error_Msg_N
6508 ("child unit overrides inherited subprogram in parent",
6510 return;
6511 end if;
6513 if Is_Non_Overriding_Operation (E, S) then
6514 Enter_Overloaded_Entity (S);
6515 if No (Derived_Type)
6516 or else Is_Tagged_Type (Derived_Type)
6517 then
6518 Check_Dispatching_Operation (S, Empty);
6519 end if;
6521 return;
6522 end if;
6524 -- E is a derived operation or an internal operator which
6525 -- is being overridden. Remove E from further visibility.
6526 -- Furthermore, if E is a dispatching operation, it must be
6527 -- replaced in the list of primitive operations of its type
6528 -- (see Override_Dispatching_Operation).
6530 Overridden_Subp := E;
6532 declare
6533 Prev : Entity_Id;
6535 begin
6536 Prev := First_Entity (Current_Scope);
6538 while Present (Prev)
6539 and then Next_Entity (Prev) /= E
6540 loop
6541 Next_Entity (Prev);
6542 end loop;
6544 -- It is possible for E to be in the current scope and
6545 -- yet not in the entity chain. This can only occur in a
6546 -- generic context where E is an implicit concatenation
6547 -- in the formal part, because in a generic body the
6548 -- entity chain starts with the formals.
6550 pragma Assert
6551 (Present (Prev) or else Chars (E) = Name_Op_Concat);
6553 -- E must be removed both from the entity_list of the
6554 -- current scope, and from the visibility chain
6556 if Debug_Flag_E then
6557 Write_Str ("Override implicit operation ");
6558 Write_Int (Int (E));
6559 Write_Eol;
6560 end if;
6562 -- If E is a predefined concatenation, it stands for four
6563 -- different operations. As a result, a single explicit
6564 -- declaration does not hide it. In a possible ambiguous
6565 -- situation, Disambiguate chooses the user-defined op,
6566 -- so it is correct to retain the previous internal one.
6568 if Chars (E) /= Name_Op_Concat
6569 or else Ekind (E) /= E_Operator
6570 then
6571 -- For nondispatching derived operations that are
6572 -- overridden by a subprogram declared in the private
6573 -- part of a package, we retain the derived
6574 -- subprogram but mark it as not immediately visible.
6575 -- If the derived operation was declared in the
6576 -- visible part then this ensures that it will still
6577 -- be visible outside the package with the proper
6578 -- signature (calls from outside must also be
6579 -- directed to this version rather than the
6580 -- overriding one, unlike the dispatching case).
6581 -- Calls from inside the package will still resolve
6582 -- to the overriding subprogram since the derived one
6583 -- is marked as not visible within the package.
6585 -- If the private operation is dispatching, we achieve
6586 -- the overriding by keeping the implicit operation
6587 -- but setting its alias to be the overriding one. In
6588 -- this fashion the proper body is executed in all
6589 -- cases, but the original signature is used outside
6590 -- of the package.
6592 -- If the overriding is not in the private part, we
6593 -- remove the implicit operation altogether.
6595 if Is_Private_Declaration (S) then
6597 if not Is_Dispatching_Operation (E) then
6598 Set_Is_Immediately_Visible (E, False);
6599 else
6600 -- Work done in Override_Dispatching_Operation,
6601 -- so nothing else need to be done here.
6603 null;
6604 end if;
6606 else
6607 -- Find predecessor of E in Homonym chain
6609 if E = Current_Entity (E) then
6610 Prev_Vis := Empty;
6611 else
6612 Prev_Vis := Current_Entity (E);
6613 while Homonym (Prev_Vis) /= E loop
6614 Prev_Vis := Homonym (Prev_Vis);
6615 end loop;
6616 end if;
6618 if Prev_Vis /= Empty then
6620 -- Skip E in the visibility chain
6622 Set_Homonym (Prev_Vis, Homonym (E));
6624 else
6625 Set_Name_Entity_Id (Chars (E), Homonym (E));
6626 end if;
6628 Set_Next_Entity (Prev, Next_Entity (E));
6630 if No (Next_Entity (Prev)) then
6631 Set_Last_Entity (Current_Scope, Prev);
6632 end if;
6634 end if;
6635 end if;
6637 Enter_Overloaded_Entity (S);
6638 Set_Is_Overriding_Operation (S);
6639 Check_Overriding_Indicator (S, E, Is_Primitive => True);
6641 -- Indicate that S overrides the operation from which
6642 -- E is inherited.
6644 if Comes_From_Source (S) then
6645 if Present (Alias (E)) then
6646 Set_Overridden_Operation (S, Alias (E));
6647 else
6648 Set_Overridden_Operation (S, E);
6649 end if;
6650 end if;
6652 if Is_Dispatching_Operation (E) then
6654 -- An overriding dispatching subprogram inherits the
6655 -- convention of the overridden subprogram (by
6656 -- AI-117).
6658 Set_Convention (S, Convention (E));
6659 Check_Dispatching_Operation (S, E);
6661 else
6662 Check_Dispatching_Operation (S, Empty);
6663 end if;
6665 Check_For_Primitive_Subprogram
6666 (Is_Primitive_Subp, Is_Overriding => True);
6667 goto Check_Inequality;
6668 end;
6670 -- Apparent redeclarations in instances can occur when two
6671 -- formal types get the same actual type. The subprograms in
6672 -- in the instance are legal, even if not callable from the
6673 -- outside. Calls from within are disambiguated elsewhere.
6674 -- For dispatching operations in the visible part, the usual
6675 -- rules apply, and operations with the same profile are not
6676 -- legal (B830001).
6678 elsif (In_Instance_Visible_Part
6679 and then not Is_Dispatching_Operation (E))
6680 or else In_Instance_Not_Visible
6681 then
6682 null;
6684 -- Here we have a real error (identical profile)
6686 else
6687 Error_Msg_Sloc := Sloc (E);
6689 -- Avoid cascaded errors if the entity appears in
6690 -- subsequent calls.
6692 Set_Scope (S, Current_Scope);
6694 -- Generate error, with extra useful warning for the case
6695 -- of a generic instance with no completion.
6697 if Is_Generic_Instance (S)
6698 and then not Has_Completion (E)
6699 then
6700 Error_Msg_N
6701 ("instantiation cannot provide body for&", S);
6702 Error_Msg_N ("\& conflicts with declaration#", S);
6703 else
6704 Error_Msg_N ("& conflicts with declaration#", S);
6705 end if;
6707 return;
6708 end if;
6710 else
6711 -- If one subprogram has an access parameter and the other
6712 -- a parameter of an access type, calls to either might be
6713 -- ambiguous. Verify that parameters match except for the
6714 -- access parameter.
6716 if May_Hide_Profile then
6717 declare
6718 F1 : Entity_Id;
6719 F2 : Entity_Id;
6720 begin
6721 F1 := First_Formal (S);
6722 F2 := First_Formal (E);
6723 while Present (F1) and then Present (F2) loop
6724 if Is_Access_Type (Etype (F1)) then
6725 if not Is_Access_Type (Etype (F2))
6726 or else not Conforming_Types
6727 (Designated_Type (Etype (F1)),
6728 Designated_Type (Etype (F2)),
6729 Type_Conformant)
6730 then
6731 May_Hide_Profile := False;
6732 end if;
6734 elsif
6735 not Conforming_Types
6736 (Etype (F1), Etype (F2), Type_Conformant)
6737 then
6738 May_Hide_Profile := False;
6739 end if;
6741 Next_Formal (F1);
6742 Next_Formal (F2);
6743 end loop;
6745 if May_Hide_Profile
6746 and then No (F1)
6747 and then No (F2)
6748 then
6749 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
6750 end if;
6751 end;
6752 end if;
6753 end if;
6755 E := Homonym (E);
6756 end loop;
6758 <<Add_New_Entity>>
6760 -- On exit, we know that S is a new entity
6762 Enter_Overloaded_Entity (S);
6763 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6764 Check_Overriding_Indicator
6765 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6767 -- If S is a derived operation for an untagged type then by
6768 -- definition it's not a dispatching operation (even if the parent
6769 -- operation was dispatching), so we don't call
6770 -- Check_Dispatching_Operation in that case.
6772 if No (Derived_Type)
6773 or else Is_Tagged_Type (Derived_Type)
6774 then
6775 Check_Dispatching_Operation (S, Empty);
6776 end if;
6777 end if;
6779 -- If this is a user-defined equality operator that is not a derived
6780 -- subprogram, create the corresponding inequality. If the operation is
6781 -- dispatching, the expansion is done elsewhere, and we do not create
6782 -- an explicit inequality operation.
6784 <<Check_Inequality>>
6785 if Chars (S) = Name_Op_Eq
6786 and then Etype (S) = Standard_Boolean
6787 and then Present (Parent (S))
6788 and then not Is_Dispatching_Operation (S)
6789 then
6790 Make_Inequality_Operator (S);
6791 end if;
6792 end New_Overloaded_Entity;
6794 ---------------------
6795 -- Process_Formals --
6796 ---------------------
6798 procedure Process_Formals
6799 (T : List_Id;
6800 Related_Nod : Node_Id)
6802 Param_Spec : Node_Id;
6803 Formal : Entity_Id;
6804 Formal_Type : Entity_Id;
6805 Default : Node_Id;
6806 Ptype : Entity_Id;
6808 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
6809 -- Check whether the default has a class-wide type. After analysis the
6810 -- default has the type of the formal, so we must also check explicitly
6811 -- for an access attribute.
6813 ---------------------------
6814 -- Is_Class_Wide_Default --
6815 ---------------------------
6817 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
6818 begin
6819 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
6820 or else (Nkind (D) = N_Attribute_Reference
6821 and then Attribute_Name (D) = Name_Access
6822 and then Is_Class_Wide_Type (Etype (Prefix (D))));
6823 end Is_Class_Wide_Default;
6825 -- Start of processing for Process_Formals
6827 begin
6828 -- In order to prevent premature use of the formals in the same formal
6829 -- part, the Ekind is left undefined until all default expressions are
6830 -- analyzed. The Ekind is established in a separate loop at the end.
6832 Param_Spec := First (T);
6833 while Present (Param_Spec) loop
6834 Formal := Defining_Identifier (Param_Spec);
6835 Set_Never_Set_In_Source (Formal, True);
6836 Enter_Name (Formal);
6838 -- Case of ordinary parameters
6840 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
6841 Find_Type (Parameter_Type (Param_Spec));
6842 Ptype := Parameter_Type (Param_Spec);
6844 if Ptype = Error then
6845 goto Continue;
6846 end if;
6848 Formal_Type := Entity (Ptype);
6850 if Is_Incomplete_Type (Formal_Type)
6851 or else
6852 (Is_Class_Wide_Type (Formal_Type)
6853 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
6854 then
6855 -- Ada 2005 (AI-326): Tagged incomplete types allowed
6857 if Is_Tagged_Type (Formal_Type) then
6858 null;
6860 -- Special handling of Value_Type for CIL case
6862 elsif Is_Value_Type (Formal_Type) then
6863 null;
6865 elsif Nkind (Parent (T)) /= N_Access_Function_Definition
6866 and then Nkind (Parent (T)) /= N_Access_Procedure_Definition
6867 then
6868 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
6870 -- An incomplete type that is not tagged is allowed in an
6871 -- access-to-subprogram type only if it is a local declaration
6872 -- with a forthcoming completion (3.10.1 (9.2/2)).
6874 elsif Scope (Formal_Type) /= Scope (Current_Scope) then
6875 Error_Msg_N
6876 ("invalid use of limited view of type", Param_Spec);
6877 end if;
6879 elsif Ekind (Formal_Type) = E_Void then
6880 Error_Msg_NE ("premature use of&",
6881 Parameter_Type (Param_Spec), Formal_Type);
6882 end if;
6884 -- Ada 2005 (AI-231): Create and decorate an internal subtype
6885 -- declaration corresponding to the null-excluding type of the
6886 -- formal in the enclosing scope. Finally, replace the parameter
6887 -- type of the formal with the internal subtype.
6889 if Ada_Version >= Ada_05
6890 and then Null_Exclusion_Present (Param_Spec)
6891 then
6892 if not Is_Access_Type (Formal_Type) then
6893 Error_Msg_N
6894 ("`NOT NULL` allowed only for an access type", Param_Spec);
6896 else
6897 if Can_Never_Be_Null (Formal_Type)
6898 and then Comes_From_Source (Related_Nod)
6899 then
6900 Error_Msg_NE
6901 ("`NOT NULL` not allowed (& already excludes null)",
6902 Param_Spec,
6903 Formal_Type);
6904 end if;
6906 Formal_Type :=
6907 Create_Null_Excluding_Itype
6908 (T => Formal_Type,
6909 Related_Nod => Related_Nod,
6910 Scope_Id => Scope (Current_Scope));
6912 -- If the designated type of the itype is an itype we
6913 -- decorate it with the Has_Delayed_Freeze attribute to
6914 -- avoid problems with the backend.
6916 -- Example:
6917 -- type T is access procedure;
6918 -- procedure Op (O : not null T);
6920 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
6921 Set_Has_Delayed_Freeze (Formal_Type);
6922 end if;
6923 end if;
6924 end if;
6926 -- An access formal type
6928 else
6929 Formal_Type :=
6930 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
6932 -- No need to continue if we already notified errors
6934 if not Present (Formal_Type) then
6935 return;
6936 end if;
6938 -- Ada 2005 (AI-254)
6940 declare
6941 AD : constant Node_Id :=
6942 Access_To_Subprogram_Definition
6943 (Parameter_Type (Param_Spec));
6944 begin
6945 if Present (AD) and then Protected_Present (AD) then
6946 Formal_Type :=
6947 Replace_Anonymous_Access_To_Protected_Subprogram
6948 (Param_Spec);
6949 end if;
6950 end;
6951 end if;
6953 Set_Etype (Formal, Formal_Type);
6954 Default := Expression (Param_Spec);
6956 if Present (Default) then
6957 if Out_Present (Param_Spec) then
6958 Error_Msg_N
6959 ("default initialization only allowed for IN parameters",
6960 Param_Spec);
6961 end if;
6963 -- Do the special preanalysis of the expression (see section on
6964 -- "Handling of Default Expressions" in the spec of package Sem).
6966 Analyze_Per_Use_Expression (Default, Formal_Type);
6968 -- Check that the designated type of an access parameter's default
6969 -- is not a class-wide type unless the parameter's designated type
6970 -- is also class-wide.
6972 if Ekind (Formal_Type) = E_Anonymous_Access_Type
6973 and then not From_With_Type (Formal_Type)
6974 and then Is_Class_Wide_Default (Default)
6975 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
6976 then
6977 Error_Msg_N
6978 ("access to class-wide expression not allowed here", Default);
6979 end if;
6980 end if;
6982 -- Ada 2005 (AI-231): Static checks
6984 if Ada_Version >= Ada_05
6985 and then Is_Access_Type (Etype (Formal))
6986 and then Can_Never_Be_Null (Etype (Formal))
6987 then
6988 Null_Exclusion_Static_Checks (Param_Spec);
6989 end if;
6991 <<Continue>>
6992 Next (Param_Spec);
6993 end loop;
6995 -- If this is the formal part of a function specification, analyze the
6996 -- subtype mark in the context where the formals are visible but not
6997 -- yet usable, and may hide outer homographs.
6999 if Nkind (Related_Nod) = N_Function_Specification then
7000 Analyze_Return_Type (Related_Nod);
7001 end if;
7003 -- Now set the kind (mode) of each formal
7005 Param_Spec := First (T);
7007 while Present (Param_Spec) loop
7008 Formal := Defining_Identifier (Param_Spec);
7009 Set_Formal_Mode (Formal);
7011 if Ekind (Formal) = E_In_Parameter then
7012 Set_Default_Value (Formal, Expression (Param_Spec));
7014 if Present (Expression (Param_Spec)) then
7015 Default := Expression (Param_Spec);
7017 if Is_Scalar_Type (Etype (Default)) then
7018 if Nkind
7019 (Parameter_Type (Param_Spec)) /= N_Access_Definition
7020 then
7021 Formal_Type := Entity (Parameter_Type (Param_Spec));
7023 else
7024 Formal_Type := Access_Definition
7025 (Related_Nod, Parameter_Type (Param_Spec));
7026 end if;
7028 Apply_Scalar_Range_Check (Default, Formal_Type);
7029 end if;
7030 end if;
7031 end if;
7033 Next (Param_Spec);
7034 end loop;
7036 end Process_Formals;
7038 ----------------------------
7039 -- Reference_Body_Formals --
7040 ----------------------------
7042 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
7043 Fs : Entity_Id;
7044 Fb : Entity_Id;
7046 begin
7047 if Error_Posted (Spec) then
7048 return;
7049 end if;
7051 -- Iterate over both lists. They may be of different lengths if the two
7052 -- specs are not conformant.
7054 Fs := First_Formal (Spec);
7055 Fb := First_Formal (Bod);
7056 while Present (Fs) and then Present (Fb) loop
7057 Generate_Reference (Fs, Fb, 'b');
7059 if Style_Check then
7060 Style.Check_Identifier (Fb, Fs);
7061 end if;
7063 Set_Spec_Entity (Fb, Fs);
7064 Set_Referenced (Fs, False);
7065 Next_Formal (Fs);
7066 Next_Formal (Fb);
7067 end loop;
7068 end Reference_Body_Formals;
7070 -------------------------
7071 -- Set_Actual_Subtypes --
7072 -------------------------
7074 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
7075 Loc : constant Source_Ptr := Sloc (N);
7076 Decl : Node_Id;
7077 Formal : Entity_Id;
7078 T : Entity_Id;
7079 First_Stmt : Node_Id := Empty;
7080 AS_Needed : Boolean;
7082 begin
7083 -- If this is an emtpy initialization procedure, no need to create
7084 -- actual subtypes (small optimization).
7086 if Ekind (Subp) = E_Procedure
7087 and then Is_Null_Init_Proc (Subp)
7088 then
7089 return;
7090 end if;
7092 Formal := First_Formal (Subp);
7093 while Present (Formal) loop
7094 T := Etype (Formal);
7096 -- We never need an actual subtype for a constrained formal
7098 if Is_Constrained (T) then
7099 AS_Needed := False;
7101 -- If we have unknown discriminants, then we do not need an actual
7102 -- subtype, or more accurately we cannot figure it out! Note that
7103 -- all class-wide types have unknown discriminants.
7105 elsif Has_Unknown_Discriminants (T) then
7106 AS_Needed := False;
7108 -- At this stage we have an unconstrained type that may need an
7109 -- actual subtype. For sure the actual subtype is needed if we have
7110 -- an unconstrained array type.
7112 elsif Is_Array_Type (T) then
7113 AS_Needed := True;
7115 -- The only other case needing an actual subtype is an unconstrained
7116 -- record type which is an IN parameter (we cannot generate actual
7117 -- subtypes for the OUT or IN OUT case, since an assignment can
7118 -- change the discriminant values. However we exclude the case of
7119 -- initialization procedures, since discriminants are handled very
7120 -- specially in this context, see the section entitled "Handling of
7121 -- Discriminants" in Einfo.
7123 -- We also exclude the case of Discrim_SO_Functions (functions used
7124 -- in front end layout mode for size/offset values), since in such
7125 -- functions only discriminants are referenced, and not only are such
7126 -- subtypes not needed, but they cannot always be generated, because
7127 -- of order of elaboration issues.
7129 elsif Is_Record_Type (T)
7130 and then Ekind (Formal) = E_In_Parameter
7131 and then Chars (Formal) /= Name_uInit
7132 and then not Is_Unchecked_Union (T)
7133 and then not Is_Discrim_SO_Function (Subp)
7134 then
7135 AS_Needed := True;
7137 -- All other cases do not need an actual subtype
7139 else
7140 AS_Needed := False;
7141 end if;
7143 -- Generate actual subtypes for unconstrained arrays and
7144 -- unconstrained discriminated records.
7146 if AS_Needed then
7147 if Nkind (N) = N_Accept_Statement then
7149 -- If expansion is active, The formal is replaced by a local
7150 -- variable that renames the corresponding entry of the
7151 -- parameter block, and it is this local variable that may
7152 -- require an actual subtype.
7154 if Expander_Active then
7155 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
7156 else
7157 Decl := Build_Actual_Subtype (T, Formal);
7158 end if;
7160 if Present (Handled_Statement_Sequence (N)) then
7161 First_Stmt :=
7162 First (Statements (Handled_Statement_Sequence (N)));
7163 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
7164 Mark_Rewrite_Insertion (Decl);
7165 else
7166 -- If the accept statement has no body, there will be no
7167 -- reference to the actuals, so no need to compute actual
7168 -- subtypes.
7170 return;
7171 end if;
7173 else
7174 Decl := Build_Actual_Subtype (T, Formal);
7175 Prepend (Decl, Declarations (N));
7176 Mark_Rewrite_Insertion (Decl);
7177 end if;
7179 -- The declaration uses the bounds of an existing object, and
7180 -- therefore needs no constraint checks.
7182 Analyze (Decl, Suppress => All_Checks);
7184 -- We need to freeze manually the generated type when it is
7185 -- inserted anywhere else than in a declarative part.
7187 if Present (First_Stmt) then
7188 Insert_List_Before_And_Analyze (First_Stmt,
7189 Freeze_Entity (Defining_Identifier (Decl), Loc));
7190 end if;
7192 if Nkind (N) = N_Accept_Statement
7193 and then Expander_Active
7194 then
7195 Set_Actual_Subtype (Renamed_Object (Formal),
7196 Defining_Identifier (Decl));
7197 else
7198 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
7199 end if;
7200 end if;
7202 Next_Formal (Formal);
7203 end loop;
7204 end Set_Actual_Subtypes;
7206 ---------------------
7207 -- Set_Formal_Mode --
7208 ---------------------
7210 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
7211 Spec : constant Node_Id := Parent (Formal_Id);
7213 begin
7214 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
7215 -- since we ensure that corresponding actuals are always valid at the
7216 -- point of the call.
7218 if Out_Present (Spec) then
7219 if Ekind (Scope (Formal_Id)) = E_Function
7220 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
7221 then
7222 Error_Msg_N ("functions can only have IN parameters", Spec);
7223 Set_Ekind (Formal_Id, E_In_Parameter);
7225 elsif In_Present (Spec) then
7226 Set_Ekind (Formal_Id, E_In_Out_Parameter);
7228 else
7229 Set_Ekind (Formal_Id, E_Out_Parameter);
7230 Set_Never_Set_In_Source (Formal_Id, True);
7231 Set_Is_True_Constant (Formal_Id, False);
7232 Set_Current_Value (Formal_Id, Empty);
7233 end if;
7235 else
7236 Set_Ekind (Formal_Id, E_In_Parameter);
7237 end if;
7239 -- Set Is_Known_Non_Null for access parameters since the language
7240 -- guarantees that access parameters are always non-null. We also set
7241 -- Can_Never_Be_Null, since there is no way to change the value.
7243 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
7245 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
7246 -- null; In Ada 2005, only if then null_exclusion is explicit.
7248 if Ada_Version < Ada_05
7249 or else Can_Never_Be_Null (Etype (Formal_Id))
7250 then
7251 Set_Is_Known_Non_Null (Formal_Id);
7252 Set_Can_Never_Be_Null (Formal_Id);
7253 end if;
7255 -- Ada 2005 (AI-231): Null-exclusion access subtype
7257 elsif Is_Access_Type (Etype (Formal_Id))
7258 and then Can_Never_Be_Null (Etype (Formal_Id))
7259 then
7260 Set_Is_Known_Non_Null (Formal_Id);
7261 end if;
7263 Set_Mechanism (Formal_Id, Default_Mechanism);
7264 Set_Formal_Validity (Formal_Id);
7265 end Set_Formal_Mode;
7267 -------------------------
7268 -- Set_Formal_Validity --
7269 -------------------------
7271 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
7272 begin
7273 -- If no validity checking, then we cannot assume anything about the
7274 -- validity of parameters, since we do not know there is any checking
7275 -- of the validity on the call side.
7277 if not Validity_Checks_On then
7278 return;
7280 -- If validity checking for parameters is enabled, this means we are
7281 -- not supposed to make any assumptions about argument values.
7283 elsif Validity_Check_Parameters then
7284 return;
7286 -- If we are checking in parameters, we will assume that the caller is
7287 -- also checking parameters, so we can assume the parameter is valid.
7289 elsif Ekind (Formal_Id) = E_In_Parameter
7290 and then Validity_Check_In_Params
7291 then
7292 Set_Is_Known_Valid (Formal_Id, True);
7294 -- Similar treatment for IN OUT parameters
7296 elsif Ekind (Formal_Id) = E_In_Out_Parameter
7297 and then Validity_Check_In_Out_Params
7298 then
7299 Set_Is_Known_Valid (Formal_Id, True);
7300 end if;
7301 end Set_Formal_Validity;
7303 ------------------------
7304 -- Subtype_Conformant --
7305 ------------------------
7307 function Subtype_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7308 Result : Boolean;
7309 begin
7310 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result);
7311 return Result;
7312 end Subtype_Conformant;
7314 ---------------------
7315 -- Type_Conformant --
7316 ---------------------
7318 function Type_Conformant
7319 (New_Id : Entity_Id;
7320 Old_Id : Entity_Id;
7321 Skip_Controlling_Formals : Boolean := False) return Boolean
7323 Result : Boolean;
7324 begin
7325 May_Hide_Profile := False;
7327 Check_Conformance
7328 (New_Id, Old_Id, Type_Conformant, False, Result,
7329 Skip_Controlling_Formals => Skip_Controlling_Formals);
7330 return Result;
7331 end Type_Conformant;
7333 -------------------------------
7334 -- Valid_Operator_Definition --
7335 -------------------------------
7337 procedure Valid_Operator_Definition (Designator : Entity_Id) is
7338 N : Integer := 0;
7339 F : Entity_Id;
7340 Id : constant Name_Id := Chars (Designator);
7341 N_OK : Boolean;
7343 begin
7344 F := First_Formal (Designator);
7345 while Present (F) loop
7346 N := N + 1;
7348 if Present (Default_Value (F)) then
7349 Error_Msg_N
7350 ("default values not allowed for operator parameters",
7351 Parent (F));
7352 end if;
7354 Next_Formal (F);
7355 end loop;
7357 -- Verify that user-defined operators have proper number of arguments
7358 -- First case of operators which can only be unary
7360 if Id = Name_Op_Not
7361 or else Id = Name_Op_Abs
7362 then
7363 N_OK := (N = 1);
7365 -- Case of operators which can be unary or binary
7367 elsif Id = Name_Op_Add
7368 or Id = Name_Op_Subtract
7369 then
7370 N_OK := (N in 1 .. 2);
7372 -- All other operators can only be binary
7374 else
7375 N_OK := (N = 2);
7376 end if;
7378 if not N_OK then
7379 Error_Msg_N
7380 ("incorrect number of arguments for operator", Designator);
7381 end if;
7383 if Id = Name_Op_Ne
7384 and then Base_Type (Etype (Designator)) = Standard_Boolean
7385 and then not Is_Intrinsic_Subprogram (Designator)
7386 then
7387 Error_Msg_N
7388 ("explicit definition of inequality not allowed", Designator);
7389 end if;
7390 end Valid_Operator_Definition;
7392 end Sem_Ch6;