1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with 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_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Lib.Xref; use Lib.Xref;
43 with Layout; use Layout;
44 with Namet; use Namet;
46 with Nlists; use Nlists;
47 with Nmake; use Nmake;
49 with Output; use Output;
50 with Rtsfind; use Rtsfind;
52 with Sem_Cat; use Sem_Cat;
53 with Sem_Ch3; use Sem_Ch3;
54 with Sem_Ch4; use Sem_Ch4;
55 with Sem_Ch5; use Sem_Ch5;
56 with Sem_Ch8; use Sem_Ch8;
57 with Sem_Ch10; use Sem_Ch10;
58 with Sem_Ch12; use Sem_Ch12;
59 with Sem_Disp; use Sem_Disp;
60 with Sem_Dist; use Sem_Dist;
61 with Sem_Elim; use Sem_Elim;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Mech; use Sem_Mech;
64 with Sem_Prag; use Sem_Prag;
65 with Sem_Res; use Sem_Res;
66 with Sem_Util; use Sem_Util;
67 with Sem_Type; use Sem_Type;
68 with Sem_Warn; use Sem_Warn;
69 with Sinput; use Sinput;
70 with Stand; use Stand;
71 with Sinfo; use Sinfo;
72 with Sinfo.CN; use Sinfo.CN;
73 with Snames; use Snames;
74 with Stringt; use Stringt;
76 with Stylesw; use Stylesw;
77 with Tbuild; use Tbuild;
78 with Uintp; use Uintp;
79 with Urealp; use Urealp;
80 with Validsw; use Validsw;
82 package body Sem_Ch6 is
84 May_Hide_Profile : Boolean := False;
85 -- This flag is used to indicate that two formals in two subprograms being
86 -- checked for conformance differ only in that one is an access parameter
87 -- while the other is of a general access type with the same designated
88 -- type. In this case, if the rest of the signatures match, a call to
89 -- either subprogram may be ambiguous, which is worth a warning. The flag
90 -- is set in Compatible_Types, and the warning emitted in
91 -- New_Overloaded_Entity.
93 -----------------------
94 -- Local Subprograms --
95 -----------------------
97 procedure Analyze_Return_Statement (N : Node_Id);
98 -- Common processing for simple_ and extended_return_statements
100 procedure Analyze_Function_Return (N : Node_Id);
101 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
102 -- applies to a [generic] function.
104 procedure Analyze_Return_Type (N : Node_Id);
105 -- Subsidiary to Process_Formals: analyze subtype mark in function
106 -- specification, in a context where the formals are visible and hide
109 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
110 -- Analyze a generic subprogram body. N is the body to be analyzed, and
111 -- Gen_Id is the defining entity Id for the corresponding spec.
113 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
114 -- If a subprogram has pragma Inline and inlining is active, use generic
115 -- machinery to build an unexpanded body for the subprogram. This body is
116 -- subsequently used for inline expansions at call sites. If subprogram can
117 -- be inlined (depending on size and nature of local declarations) this
118 -- function returns true. Otherwise subprogram body is treated normally.
119 -- If proper warnings are enabled and the subprogram contains a construct
120 -- that cannot be inlined, the offending construct is flagged accordingly.
122 procedure Check_Conformance
125 Ctype : Conformance_Type;
127 Conforms : out Boolean;
128 Err_Loc : Node_Id := Empty;
129 Get_Inst : Boolean := False;
130 Skip_Controlling_Formals : Boolean := False);
131 -- Given two entities, this procedure checks that the profiles associated
132 -- with these entities meet the conformance criterion given by the third
133 -- parameter. If they conform, Conforms is set True and control returns
134 -- to the caller. If they do not conform, Conforms is set to False, and
135 -- in addition, if Errmsg is True on the call, proper messages are output
136 -- to complain about the conformance failure. If Err_Loc is non_Empty
137 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
138 -- error messages are placed on the appropriate part of the construct
139 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
140 -- against a formal access-to-subprogram type so Get_Instance_Of must
143 procedure Check_Subprogram_Order (N : Node_Id);
144 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
145 -- the alpha ordering rule for N if this ordering requirement applicable.
147 procedure Check_Returns
151 Proc : Entity_Id := Empty);
152 -- Called to check for missing return statements in a function body, or for
153 -- returns present in a procedure body which has No_Return set. HSS is the
154 -- handled statement sequence for the subprogram body. This procedure
155 -- checks all flow paths to make sure they either have return (Mode = 'F',
156 -- used for functions) or do not have a return (Mode = 'P', used for
157 -- No_Return procedures). The flag Err is set if there are any control
158 -- paths not explicitly terminated by a return in the function case, and is
159 -- True otherwise. Proc is the entity for the procedure case and is used
160 -- in posting the warning message.
162 procedure Enter_Overloaded_Entity (S : Entity_Id);
163 -- This procedure makes S, a new overloaded entity, into the first visible
164 -- entity with that name.
166 procedure Install_Entity (E : Entity_Id);
167 -- Make single entity visible. Used for generic formals as well
169 function Is_Non_Overriding_Operation
171 New_E : Entity_Id) return Boolean;
172 -- Enforce the rule given in 12.3(18): a private operation in an instance
173 -- overrides an inherited operation only if the corresponding operation
174 -- was overriding in the generic. This can happen for primitive operations
175 -- of types derived (in the generic unit) from formal private or formal
178 procedure Make_Inequality_Operator (S : Entity_Id);
179 -- Create the declaration for an inequality operator that is implicitly
180 -- created by a user-defined equality operator that yields a boolean.
182 procedure May_Need_Actuals (Fun : Entity_Id);
183 -- Flag functions that can be called without parameters, i.e. those that
184 -- have no parameters, or those for which defaults exist for all parameters
186 procedure Process_PPCs
189 Body_Id : Entity_Id);
190 -- Called from Analyze_Body to deal with scanning post conditions for the
191 -- body and assembling and inserting the _postconditions procedure. N is
192 -- the node for the subprogram body and Body_Id/Spec_Id are the entities
193 -- for the body and separate spec (if there is no separate spec, Spec_Id
196 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
197 -- Formal_Id is an formal parameter entity. This procedure deals with
198 -- setting the proper validity status for this entity, which depends
199 -- on the kind of parameter and the validity checking mode.
201 ------------------------------
202 -- Analyze_Return_Statement --
203 ------------------------------
205 procedure Analyze_Return_Statement (N : Node_Id) is
207 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
208 N_Extended_Return_Statement));
210 Returns_Object : constant Boolean :=
211 Nkind (N) = N_Extended_Return_Statement
213 (Nkind (N) = N_Simple_Return_Statement
214 and then Present (Expression (N)));
215 -- True if we're returning something; that is, "return <expression>;"
216 -- or "return Result : T [:= ...]". False for "return;". Used for error
217 -- checking: If Returns_Object is True, N should apply to a function
218 -- body; otherwise N should apply to a procedure body, entry body,
219 -- accept statement, or extended return statement.
221 function Find_What_It_Applies_To return Entity_Id;
222 -- Find the entity representing the innermost enclosing body, accept
223 -- statement, or extended return statement. If the result is a callable
224 -- construct or extended return statement, then this will be the value
225 -- of the Return_Applies_To attribute. Otherwise, the program is
226 -- illegal. See RM-6.5(4/2).
228 -----------------------------
229 -- Find_What_It_Applies_To --
230 -----------------------------
232 function Find_What_It_Applies_To return Entity_Id is
233 Result : Entity_Id := Empty;
236 -- Loop outward through the Scope_Stack, skipping blocks and loops
238 for J in reverse 0 .. Scope_Stack.Last loop
239 Result := Scope_Stack.Table (J).Entity;
240 exit when Ekind (Result) /= E_Block and then
241 Ekind (Result) /= E_Loop;
244 pragma Assert (Present (Result));
246 end Find_What_It_Applies_To;
248 -- Local declarations
250 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
251 Kind : constant Entity_Kind := Ekind (Scope_Id);
252 Loc : constant Source_Ptr := Sloc (N);
253 Stm_Entity : constant Entity_Id :=
255 (E_Return_Statement, Current_Scope, Loc, 'R');
257 -- Start of processing for Analyze_Return_Statement
260 Set_Return_Statement_Entity (N, Stm_Entity);
262 Set_Etype (Stm_Entity, Standard_Void_Type);
263 Set_Return_Applies_To (Stm_Entity, Scope_Id);
265 -- Place Return entity on scope stack, to simplify enforcement of 6.5
266 -- (4/2): an inner return statement will apply to this extended return.
268 if Nkind (N) = N_Extended_Return_Statement then
269 Push_Scope (Stm_Entity);
272 -- Check that pragma No_Return is obeyed
274 if No_Return (Scope_Id) then
275 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
278 -- Warn on any unassigned OUT parameters if in procedure
280 if Ekind (Scope_Id) = E_Procedure then
281 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
284 -- Check that functions return objects, and other things do not
286 if Kind = E_Function or else Kind = E_Generic_Function then
287 if not Returns_Object then
288 Error_Msg_N ("missing expression in return from function", N);
291 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
292 if Returns_Object then
293 Error_Msg_N ("procedure cannot return value (use function)", N);
296 elsif Kind = E_Entry or else Kind = E_Entry_Family then
297 if Returns_Object then
298 if Is_Protected_Type (Scope (Scope_Id)) then
299 Error_Msg_N ("entry body cannot return value", N);
301 Error_Msg_N ("accept statement cannot return value", N);
305 elsif Kind = E_Return_Statement then
307 -- We are nested within another return statement, which must be an
308 -- extended_return_statement.
310 if Returns_Object then
312 ("extended_return_statement cannot return value; " &
313 "use `""RETURN;""`", N);
317 Error_Msg_N ("illegal context for return statement", N);
320 if Kind = E_Function or else Kind = E_Generic_Function then
321 Analyze_Function_Return (N);
324 if Nkind (N) = N_Extended_Return_Statement then
328 Kill_Current_Values (Last_Assignment_Only => True);
329 Check_Unreachable_Code (N);
330 end Analyze_Return_Statement;
332 ---------------------------------------------
333 -- Analyze_Abstract_Subprogram_Declaration --
334 ---------------------------------------------
336 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
337 Designator : constant Entity_Id :=
338 Analyze_Subprogram_Specification (Specification (N));
339 Scop : constant Entity_Id := Current_Scope;
342 Generate_Definition (Designator);
343 Set_Is_Abstract_Subprogram (Designator);
344 New_Overloaded_Entity (Designator);
345 Check_Delayed_Subprogram (Designator);
347 Set_Categorization_From_Scope (Designator, Scop);
349 if Ekind (Scope (Designator)) = E_Protected_Type then
351 ("abstract subprogram not allowed in protected type", N);
353 -- Issue a warning if the abstract subprogram is neither a dispatching
354 -- operation nor an operation that overrides an inherited subprogram or
355 -- predefined operator, since this most likely indicates a mistake.
357 elsif Warn_On_Redundant_Constructs
358 and then not Is_Dispatching_Operation (Designator)
359 and then not Is_Overriding_Operation (Designator)
360 and then (not Is_Operator_Symbol_Name (Chars (Designator))
361 or else Scop /= Scope (Etype (First_Formal (Designator))))
364 ("?abstract subprogram is not dispatching or overriding", N);
367 Generate_Reference_To_Formals (Designator);
368 end Analyze_Abstract_Subprogram_Declaration;
370 ----------------------------------------
371 -- Analyze_Extended_Return_Statement --
372 ----------------------------------------
374 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
376 Analyze_Return_Statement (N);
377 end Analyze_Extended_Return_Statement;
379 ----------------------------
380 -- Analyze_Function_Call --
381 ----------------------------
383 procedure Analyze_Function_Call (N : Node_Id) is
384 P : constant Node_Id := Name (N);
385 L : constant List_Id := Parameter_Associations (N);
391 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
392 -- as B (A, X). If the rewriting is successful, the call has been
393 -- analyzed and we just return.
395 if Nkind (P) = N_Selected_Component
396 and then Name (N) /= P
397 and then Is_Rewrite_Substitution (N)
398 and then Present (Etype (N))
403 -- If error analyzing name, then set Any_Type as result type and return
405 if Etype (P) = Any_Type then
406 Set_Etype (N, Any_Type);
410 -- Otherwise analyze the parameters
414 while Present (Actual) loop
416 Check_Parameterless_Call (Actual);
422 end Analyze_Function_Call;
424 -----------------------------
425 -- Analyze_Function_Return --
426 -----------------------------
428 procedure Analyze_Function_Return (N : Node_Id) is
429 Loc : constant Source_Ptr := Sloc (N);
430 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
431 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
433 R_Type : constant Entity_Id := Etype (Scope_Id);
434 -- Function result subtype
436 procedure Check_Limited_Return (Expr : Node_Id);
437 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
438 -- limited types. Used only for simple return statements.
439 -- Expr is the expression returned.
441 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
442 -- Check that the return_subtype_indication properly matches the result
443 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
445 --------------------------
446 -- Check_Limited_Return --
447 --------------------------
449 procedure Check_Limited_Return (Expr : Node_Id) is
451 -- Ada 2005 (AI-318-02): Return-by-reference types have been
452 -- removed and replaced by anonymous access results. This is an
453 -- incompatibility with Ada 95. Not clear whether this should be
454 -- enforced yet or perhaps controllable with special switch. ???
456 if Is_Limited_Type (R_Type)
457 and then Comes_From_Source (N)
458 and then not In_Instance_Body
459 and then not OK_For_Limited_Init_In_05 (Expr)
463 if Ada_Version >= Ada_05
464 and then not Debug_Flag_Dot_L
465 and then not GNAT_Mode
468 ("(Ada 2005) cannot copy object of a limited type " &
469 "(RM-2005 6.5(5.5/2))", Expr);
470 if Is_Inherently_Limited_Type (R_Type) then
472 ("\return by reference not permitted in Ada 2005", Expr);
475 -- Warn in Ada 95 mode, to give folks a heads up about this
478 -- In GNAT mode, this is just a warning, to allow it to be
479 -- evilly turned off. Otherwise it is a real error.
481 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
482 if Is_Inherently_Limited_Type (R_Type) then
484 ("return by reference not permitted in Ada 2005 " &
485 "(RM-2005 6.5(5.5/2))?", Expr);
488 ("cannot copy object of a limited type in Ada 2005 " &
489 "(RM-2005 6.5(5.5/2))?", Expr);
492 -- Ada 95 mode, compatibility warnings disabled
495 return; -- skip continuation messages below
499 ("\consider switching to return of access type", Expr);
500 Explain_Limited_Type (R_Type, Expr);
502 end Check_Limited_Return;
504 -------------------------------------
505 -- Check_Return_Subtype_Indication --
506 -------------------------------------
508 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
509 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
510 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
511 -- Subtype given in the extended return statement;
512 -- this must match R_Type.
514 Subtype_Ind : constant Node_Id :=
515 Object_Definition (Original_Node (Obj_Decl));
517 R_Type_Is_Anon_Access :
519 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
521 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
523 Ekind (R_Type) = E_Anonymous_Access_Type;
524 -- True if return type of the function is an anonymous access type
525 -- Can't we make Is_Anonymous_Access_Type in einfo ???
527 R_Stm_Type_Is_Anon_Access :
529 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
531 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
533 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
534 -- True if type of the return object is an anonymous access type
537 -- First, avoid cascade errors:
539 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
543 -- "return access T" case; check that the return statement also has
544 -- "access T", and that the subtypes statically match:
545 -- if this is an access to subprogram the signatures must match.
547 if R_Type_Is_Anon_Access then
548 if R_Stm_Type_Is_Anon_Access then
550 Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
552 if Base_Type (Designated_Type (R_Stm_Type)) /=
553 Base_Type (Designated_Type (R_Type))
554 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
557 ("subtype must statically match function result subtype",
558 Subtype_Mark (Subtype_Ind));
562 -- For two anonymous access to subprogram types, the
563 -- types themselves must be type conformant.
565 if not Conforming_Types
566 (R_Stm_Type, R_Type, Fully_Conformant)
569 ("subtype must statically match function result subtype",
575 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
578 -- Subtype_indication case; check that the types are the same, and
579 -- statically match if appropriate. A null exclusion may be present
580 -- on the return type, on the function specification, on the object
581 -- declaration or on the subtype itself.
583 elsif Base_Type (R_Stm_Type) = Base_Type (R_Type) then
584 if Is_Access_Type (R_Type)
586 (Can_Never_Be_Null (R_Type)
587 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
588 Can_Never_Be_Null (R_Stm_Type)
591 ("subtype must statically match function result subtype",
595 if Is_Constrained (R_Type) then
596 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
598 ("subtype must statically match function result subtype",
603 -- If the function's result type doesn't match the return object
604 -- entity's type, then we check for the case where the result type
605 -- is class-wide, and allow the declaration if the type of the object
606 -- definition matches the class-wide type. This prevents rejection
607 -- in the case where the object declaration is initialized by a call
608 -- to a build-in-place function with a specific result type and the
609 -- object entity had its type changed to that specific type. This is
610 -- also allowed in the case where Obj_Decl does not come from source,
611 -- which can occur for an expansion of a simple return statement of
612 -- a build-in-place class-wide function when the result expression
613 -- has a specific type, because a return object with a specific type
614 -- is created. (Note that the ARG believes that return objects should
615 -- be allowed to have a type covered by a class-wide result type in
616 -- any case, so once that relaxation is made (see AI05-32), the above
617 -- check for type compatibility should be changed to test Covers
618 -- rather than equality, and the following special test will no
619 -- longer be needed. ???)
621 elsif Is_Class_Wide_Type (R_Type)
623 (R_Type = Etype (Object_Definition (Original_Node (Obj_Decl)))
624 or else not Comes_From_Source (Obj_Decl))
630 ("wrong type for return_subtype_indication", Subtype_Ind);
632 end Check_Return_Subtype_Indication;
634 ---------------------
635 -- Local Variables --
636 ---------------------
640 -- Start of processing for Analyze_Function_Return
643 Set_Return_Present (Scope_Id);
645 if Nkind (N) = N_Simple_Return_Statement then
646 Expr := Expression (N);
647 Analyze_And_Resolve (Expr, R_Type);
648 Check_Limited_Return (Expr);
651 -- Analyze parts specific to extended_return_statement:
654 Obj_Decl : constant Node_Id :=
655 Last (Return_Object_Declarations (N));
657 HSS : constant Node_Id := Handled_Statement_Sequence (N);
660 Expr := Expression (Obj_Decl);
662 -- Note: The check for OK_For_Limited_Init will happen in
663 -- Analyze_Object_Declaration; we treat it as a normal
664 -- object declaration.
666 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
669 Check_Return_Subtype_Indication (Obj_Decl);
671 if Present (HSS) then
674 if Present (Exception_Handlers (HSS)) then
676 -- ???Has_Nested_Block_With_Handler needs to be set.
677 -- Probably by creating an actual N_Block_Statement.
678 -- Probably in Expand.
684 Check_References (Stm_Entity);
688 -- Case of Expr present
692 -- Defend against previous errors
694 and then Nkind (Expr) /= N_Empty
695 and then Present (Etype (Expr))
697 -- Apply constraint check. Note that this is done before the implicit
698 -- conversion of the expression done for anonymous access types to
699 -- ensure correct generation of the null-excluding check associated
700 -- with null-excluding expressions found in return statements.
702 Apply_Constraint_Check (Expr, R_Type);
704 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
705 -- type, apply an implicit conversion of the expression to that type
706 -- to force appropriate static and run-time accessibility checks.
708 if Ada_Version >= Ada_05
709 and then Ekind (R_Type) = E_Anonymous_Access_Type
711 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
712 Analyze_And_Resolve (Expr, R_Type);
715 -- If the result type is class-wide, then check that the return
716 -- expression's type is not declared at a deeper level than the
717 -- function (RM05-6.5(5.6/2)).
719 if Ada_Version >= Ada_05
720 and then Is_Class_Wide_Type (R_Type)
722 if Type_Access_Level (Etype (Expr)) >
723 Subprogram_Access_Level (Scope_Id)
726 ("level of return expression type is deeper than " &
727 "class-wide function!", Expr);
731 if (Is_Class_Wide_Type (Etype (Expr))
732 or else Is_Dynamically_Tagged (Expr))
733 and then not Is_Class_Wide_Type (R_Type)
736 ("dynamically tagged expression not allowed!", Expr);
739 -- ??? A real run-time accessibility check is needed in cases
740 -- involving dereferences of access parameters. For now we just
741 -- check the static cases.
743 if (Ada_Version < Ada_05 or else Debug_Flag_Dot_L)
744 and then Is_Inherently_Limited_Type (Etype (Scope_Id))
745 and then Object_Access_Level (Expr) >
746 Subprogram_Access_Level (Scope_Id)
749 Make_Raise_Program_Error (Loc,
750 Reason => PE_Accessibility_Check_Failed));
754 ("cannot return a local value by reference?", N);
756 ("\& will be raised at run time?",
757 N, Standard_Program_Error);
761 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
762 and then Null_Exclusion_Present (Parent (Scope_Id))
764 Apply_Compile_Time_Constraint_Error
766 Msg => "(Ada 2005) null not allowed for "
767 & "null-excluding return?",
768 Reason => CE_Null_Not_Allowed);
771 end Analyze_Function_Return;
773 -------------------------------------
774 -- Analyze_Generic_Subprogram_Body --
775 -------------------------------------
777 procedure Analyze_Generic_Subprogram_Body
781 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
782 Kind : constant Entity_Kind := Ekind (Gen_Id);
788 -- Copy body and disable expansion while analyzing the generic For a
789 -- stub, do not copy the stub (which would load the proper body), this
790 -- will be done when the proper body is analyzed.
792 if Nkind (N) /= N_Subprogram_Body_Stub then
793 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
798 Spec := Specification (N);
800 -- Within the body of the generic, the subprogram is callable, and
801 -- behaves like the corresponding non-generic unit.
803 Body_Id := Defining_Entity (Spec);
805 if Kind = E_Generic_Procedure
806 and then Nkind (Spec) /= N_Procedure_Specification
808 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
811 elsif Kind = E_Generic_Function
812 and then Nkind (Spec) /= N_Function_Specification
814 Error_Msg_N ("invalid body for generic function ", Body_Id);
818 Set_Corresponding_Body (Gen_Decl, Body_Id);
820 if Has_Completion (Gen_Id)
821 and then Nkind (Parent (N)) /= N_Subunit
823 Error_Msg_N ("duplicate generic body", N);
826 Set_Has_Completion (Gen_Id);
829 if Nkind (N) = N_Subprogram_Body_Stub then
830 Set_Ekind (Defining_Entity (Specification (N)), Kind);
832 Set_Corresponding_Spec (N, Gen_Id);
835 if Nkind (Parent (N)) = N_Compilation_Unit then
836 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
839 -- Make generic parameters immediately visible in the body. They are
840 -- needed to process the formals declarations. Then make the formals
841 -- visible in a separate step.
847 First_Ent : Entity_Id;
850 First_Ent := First_Entity (Gen_Id);
853 while Present (E) and then not Is_Formal (E) loop
858 Set_Use (Generic_Formal_Declarations (Gen_Decl));
860 -- Now generic formals are visible, and the specification can be
861 -- analyzed, for subsequent conformance check.
863 Body_Id := Analyze_Subprogram_Specification (Spec);
865 -- Make formal parameters visible
869 -- E is the first formal parameter, we loop through the formals
870 -- installing them so that they will be visible.
872 Set_First_Entity (Gen_Id, E);
873 while Present (E) loop
879 -- Visible generic entity is callable within its own body
881 Set_Ekind (Gen_Id, Ekind (Body_Id));
882 Set_Ekind (Body_Id, E_Subprogram_Body);
883 Set_Convention (Body_Id, Convention (Gen_Id));
884 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
885 Set_Scope (Body_Id, Scope (Gen_Id));
886 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
888 if Nkind (N) = N_Subprogram_Body_Stub then
890 -- No body to analyze, so restore state of generic unit
892 Set_Ekind (Gen_Id, Kind);
893 Set_Ekind (Body_Id, Kind);
895 if Present (First_Ent) then
896 Set_First_Entity (Gen_Id, First_Ent);
903 -- If this is a compilation unit, it must be made visible explicitly,
904 -- because the compilation of the declaration, unlike other library
905 -- unit declarations, does not. If it is not a unit, the following
906 -- is redundant but harmless.
908 Set_Is_Immediately_Visible (Gen_Id);
909 Reference_Body_Formals (Gen_Id, Body_Id);
911 if Is_Child_Unit (Gen_Id) then
912 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
915 Set_Actual_Subtypes (N, Current_Scope);
916 Process_PPCs (N, Gen_Id, Body_Id);
918 -- If the generic unit carries pre- or post-conditions, copy them
919 -- to the original generic tree, so that they are properly added
920 -- to any instantiation.
923 Orig : constant Node_Id := Original_Node (N);
927 Cond := First (Declarations (N));
928 while Present (Cond) loop
929 if Nkind (Cond) = N_Pragma
930 and then Pragma_Name (Cond) = Name_Check
932 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
934 elsif Nkind (Cond) = N_Pragma
935 and then Pragma_Name (Cond) = Name_Postcondition
937 Set_Ekind (Defining_Entity (Orig), Ekind (Gen_Id));
938 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
947 Analyze_Declarations (Declarations (N));
949 Analyze (Handled_Statement_Sequence (N));
951 Save_Global_References (Original_Node (N));
953 -- Prior to exiting the scope, include generic formals again (if any
954 -- are present) in the set of local entities.
956 if Present (First_Ent) then
957 Set_First_Entity (Gen_Id, First_Ent);
960 Check_References (Gen_Id);
963 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
965 Check_Subprogram_Order (N);
967 -- Outside of its body, unit is generic again
969 Set_Ekind (Gen_Id, Kind);
970 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
973 Style.Check_Identifier (Body_Id, Gen_Id);
976 end Analyze_Generic_Subprogram_Body;
978 -----------------------------
979 -- Analyze_Operator_Symbol --
980 -----------------------------
982 -- An operator symbol such as "+" or "and" may appear in context where the
983 -- literal denotes an entity name, such as "+"(x, y) or in context when it
984 -- is just a string, as in (conjunction = "or"). In these cases the parser
985 -- generates this node, and the semantics does the disambiguation. Other
986 -- such case are actuals in an instantiation, the generic unit in an
987 -- instantiation, and pragma arguments.
989 procedure Analyze_Operator_Symbol (N : Node_Id) is
990 Par : constant Node_Id := Parent (N);
993 if (Nkind (Par) = N_Function_Call
994 and then N = Name (Par))
995 or else Nkind (Par) = N_Function_Instantiation
996 or else (Nkind (Par) = N_Indexed_Component
997 and then N = Prefix (Par))
998 or else (Nkind (Par) = N_Pragma_Argument_Association
999 and then not Is_Pragma_String_Literal (Par))
1000 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1001 or else (Nkind (Par) = N_Attribute_Reference
1002 and then Attribute_Name (Par) /= Name_Value)
1004 Find_Direct_Name (N);
1007 Change_Operator_Symbol_To_String_Literal (N);
1010 end Analyze_Operator_Symbol;
1012 -----------------------------------
1013 -- Analyze_Parameter_Association --
1014 -----------------------------------
1016 procedure Analyze_Parameter_Association (N : Node_Id) is
1018 Analyze (Explicit_Actual_Parameter (N));
1019 end Analyze_Parameter_Association;
1021 ----------------------------
1022 -- Analyze_Procedure_Call --
1023 ----------------------------
1025 procedure Analyze_Procedure_Call (N : Node_Id) is
1026 Loc : constant Source_Ptr := Sloc (N);
1027 P : constant Node_Id := Name (N);
1028 Actuals : constant List_Id := Parameter_Associations (N);
1032 procedure Analyze_Call_And_Resolve;
1033 -- Do Analyze and Resolve calls for procedure call
1035 ------------------------------
1036 -- Analyze_Call_And_Resolve --
1037 ------------------------------
1039 procedure Analyze_Call_And_Resolve is
1041 if Nkind (N) = N_Procedure_Call_Statement then
1043 Resolve (N, Standard_Void_Type);
1047 end Analyze_Call_And_Resolve;
1049 -- Start of processing for Analyze_Procedure_Call
1052 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1053 -- a procedure call or an entry call. The prefix may denote an access
1054 -- to subprogram type, in which case an implicit dereference applies.
1055 -- If the prefix is an indexed component (without implicit dereference)
1056 -- then the construct denotes a call to a member of an entire family.
1057 -- If the prefix is a simple name, it may still denote a call to a
1058 -- parameterless member of an entry family. Resolution of these various
1059 -- interpretations is delicate.
1063 -- If this is a call of the form Obj.Op, the call may have been
1064 -- analyzed and possibly rewritten into a block, in which case
1067 if Analyzed (N) then
1071 -- If error analyzing prefix, then set Any_Type as result and return
1073 if Etype (P) = Any_Type then
1074 Set_Etype (N, Any_Type);
1078 -- Otherwise analyze the parameters
1080 if Present (Actuals) then
1081 Actual := First (Actuals);
1083 while Present (Actual) loop
1085 Check_Parameterless_Call (Actual);
1090 -- Special processing for Elab_Spec and Elab_Body calls
1092 if Nkind (P) = N_Attribute_Reference
1093 and then (Attribute_Name (P) = Name_Elab_Spec
1094 or else Attribute_Name (P) = Name_Elab_Body)
1096 if Present (Actuals) then
1098 ("no parameters allowed for this call", First (Actuals));
1102 Set_Etype (N, Standard_Void_Type);
1105 elsif Is_Entity_Name (P)
1106 and then Is_Record_Type (Etype (Entity (P)))
1107 and then Remote_AST_I_Dereference (P)
1111 elsif Is_Entity_Name (P)
1112 and then Ekind (Entity (P)) /= E_Entry_Family
1114 if Is_Access_Type (Etype (P))
1115 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1116 and then No (Actuals)
1117 and then Comes_From_Source (N)
1119 Error_Msg_N ("missing explicit dereference in call", N);
1122 Analyze_Call_And_Resolve;
1124 -- If the prefix is the simple name of an entry family, this is
1125 -- a parameterless call from within the task body itself.
1127 elsif Is_Entity_Name (P)
1128 and then Nkind (P) = N_Identifier
1129 and then Ekind (Entity (P)) = E_Entry_Family
1130 and then Present (Actuals)
1131 and then No (Next (First (Actuals)))
1133 -- Can be call to parameterless entry family. What appears to be the
1134 -- sole argument is in fact the entry index. Rewrite prefix of node
1135 -- accordingly. Source representation is unchanged by this
1139 Make_Indexed_Component (Loc,
1141 Make_Selected_Component (Loc,
1142 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1143 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1144 Expressions => Actuals);
1145 Set_Name (N, New_N);
1146 Set_Etype (New_N, Standard_Void_Type);
1147 Set_Parameter_Associations (N, No_List);
1148 Analyze_Call_And_Resolve;
1150 elsif Nkind (P) = N_Explicit_Dereference then
1151 if Ekind (Etype (P)) = E_Subprogram_Type then
1152 Analyze_Call_And_Resolve;
1154 Error_Msg_N ("expect access to procedure in call", P);
1157 -- The name can be a selected component or an indexed component that
1158 -- yields an access to subprogram. Such a prefix is legal if the call
1159 -- has parameter associations.
1161 elsif Is_Access_Type (Etype (P))
1162 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1164 if Present (Actuals) then
1165 Analyze_Call_And_Resolve;
1167 Error_Msg_N ("missing explicit dereference in call ", N);
1170 -- If not an access to subprogram, then the prefix must resolve to the
1171 -- name of an entry, entry family, or protected operation.
1173 -- For the case of a simple entry call, P is a selected component where
1174 -- the prefix is the task and the selector name is the entry. A call to
1175 -- a protected procedure will have the same syntax. If the protected
1176 -- object contains overloaded operations, the entity may appear as a
1177 -- function, the context will select the operation whose type is Void.
1179 elsif Nkind (P) = N_Selected_Component
1180 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1182 Ekind (Entity (Selector_Name (P))) = E_Procedure
1184 Ekind (Entity (Selector_Name (P))) = E_Function)
1186 Analyze_Call_And_Resolve;
1188 elsif Nkind (P) = N_Selected_Component
1189 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1190 and then Present (Actuals)
1191 and then No (Next (First (Actuals)))
1193 -- Can be call to parameterless entry family. What appears to be the
1194 -- sole argument is in fact the entry index. Rewrite prefix of node
1195 -- accordingly. Source representation is unchanged by this
1199 Make_Indexed_Component (Loc,
1200 Prefix => New_Copy (P),
1201 Expressions => Actuals);
1202 Set_Name (N, New_N);
1203 Set_Etype (New_N, Standard_Void_Type);
1204 Set_Parameter_Associations (N, No_List);
1205 Analyze_Call_And_Resolve;
1207 -- For the case of a reference to an element of an entry family, P is
1208 -- an indexed component whose prefix is a selected component (task and
1209 -- entry family), and whose index is the entry family index.
1211 elsif Nkind (P) = N_Indexed_Component
1212 and then Nkind (Prefix (P)) = N_Selected_Component
1213 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1215 Analyze_Call_And_Resolve;
1217 -- If the prefix is the name of an entry family, it is a call from
1218 -- within the task body itself.
1220 elsif Nkind (P) = N_Indexed_Component
1221 and then Nkind (Prefix (P)) = N_Identifier
1222 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1225 Make_Selected_Component (Loc,
1226 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1227 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1228 Rewrite (Prefix (P), New_N);
1230 Analyze_Call_And_Resolve;
1232 -- Anything else is an error
1235 Error_Msg_N ("invalid procedure or entry call", N);
1237 end Analyze_Procedure_Call;
1239 -------------------------------------
1240 -- Analyze_Simple_Return_Statement --
1241 -------------------------------------
1243 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1245 if Present (Expression (N)) then
1246 Mark_Coextensions (N, Expression (N));
1249 Analyze_Return_Statement (N);
1250 end Analyze_Simple_Return_Statement;
1252 -------------------------
1253 -- Analyze_Return_Type --
1254 -------------------------
1256 procedure Analyze_Return_Type (N : Node_Id) is
1257 Designator : constant Entity_Id := Defining_Entity (N);
1258 Typ : Entity_Id := Empty;
1261 -- Normal case where result definition does not indicate an error
1263 if Result_Definition (N) /= Error then
1264 if Nkind (Result_Definition (N)) = N_Access_Definition then
1266 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1269 AD : constant Node_Id :=
1270 Access_To_Subprogram_Definition (Result_Definition (N));
1272 if Present (AD) and then Protected_Present (AD) then
1273 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1275 Typ := Access_Definition (N, Result_Definition (N));
1279 Set_Parent (Typ, Result_Definition (N));
1280 Set_Is_Local_Anonymous_Access (Typ);
1281 Set_Etype (Designator, Typ);
1283 -- Subtype_Mark case
1286 Find_Type (Result_Definition (N));
1287 Typ := Entity (Result_Definition (N));
1288 Set_Etype (Designator, Typ);
1290 if Ekind (Typ) = E_Incomplete_Type
1291 and then Is_Value_Type (Typ)
1295 elsif Ekind (Typ) = E_Incomplete_Type
1296 or else (Is_Class_Wide_Type (Typ)
1298 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1301 ("invalid use of incomplete type", Result_Definition (N));
1305 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1307 Null_Exclusion_Static_Checks (N);
1309 -- Case where result definition does indicate an error
1312 Set_Etype (Designator, Any_Type);
1314 end Analyze_Return_Type;
1316 -----------------------------
1317 -- Analyze_Subprogram_Body --
1318 -----------------------------
1320 -- This procedure is called for regular subprogram bodies, generic bodies,
1321 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1322 -- specification matters, and is used to create a proper declaration for
1323 -- the subprogram, or to perform conformance checks.
1325 procedure Analyze_Subprogram_Body (N : Node_Id) is
1326 Loc : constant Source_Ptr := Sloc (N);
1327 Body_Deleted : constant Boolean := False;
1328 Body_Spec : constant Node_Id := Specification (N);
1329 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1330 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1331 Conformant : Boolean;
1333 Missing_Ret : Boolean;
1335 Prot_Typ : Entity_Id := Empty;
1336 Spec_Id : Entity_Id;
1337 Spec_Decl : Node_Id := Empty;
1339 Last_Real_Spec_Entity : Entity_Id := Empty;
1340 -- When we analyze a separate spec, the entity chain ends up containing
1341 -- the formals, as well as any itypes generated during analysis of the
1342 -- default expressions for parameters, or the arguments of associated
1343 -- precondition/postcondition pragmas (which are analyzed in the context
1344 -- of the spec since they have visibility on formals).
1346 -- These entities belong with the spec and not the body. However we do
1347 -- the analysis of the body in the context of the spec (again to obtain
1348 -- visibility to the formals), and all the entities generated during
1349 -- this analysis end up also chained to the entity chain of the spec.
1350 -- But they really belong to the body, and there is circuitry to move
1351 -- them from the spec to the body.
1353 -- However, when we do this move, we don't want to move the real spec
1354 -- entities (first para above) to the body. The Last_Real_Spec_Entity
1355 -- variable points to the last real spec entity, so we only move those
1356 -- chained beyond that point. It is initialized to Empty to deal with
1357 -- the case where there is no separate spec.
1359 procedure Check_Anonymous_Return;
1360 -- (Ada 2005): if a function returns an access type that denotes a task,
1361 -- or a type that contains tasks, we must create a master entity for
1362 -- the anonymous type, which typically will be used in an allocator
1363 -- in the body of the function.
1365 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1366 -- Look ahead to recognize a pragma that may appear after the body.
1367 -- If there is a previous spec, check that it appears in the same
1368 -- declarative part. If the pragma is Inline_Always, perform inlining
1369 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1370 -- If the body acts as a spec, and inlining is required, we create a
1371 -- subprogram declaration for it, in order to attach the body to inline.
1372 -- If pragma does not appear after the body, check whether there is
1373 -- an inline pragma before any local declarations.
1375 function Disambiguate_Spec return Entity_Id;
1376 -- When a primitive is declared between the private view and the full
1377 -- view of a concurrent type which implements an interface, a special
1378 -- mechanism is used to find the corresponding spec of the primitive
1381 function Is_Private_Concurrent_Primitive
1382 (Subp_Id : Entity_Id) return Boolean;
1383 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
1384 -- type that implements an interface and has a private view.
1386 procedure Set_Trivial_Subprogram (N : Node_Id);
1387 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
1388 -- subprogram whose body is being analyzed. N is the statement node
1389 -- causing the flag to be set, if the following statement is a return
1390 -- of an entity, we mark the entity as set in source to suppress any
1391 -- warning on the stylized use of function stubs with a dummy return.
1393 procedure Verify_Overriding_Indicator;
1394 -- If there was a previous spec, the entity has been entered in the
1395 -- current scope previously. If the body itself carries an overriding
1396 -- indicator, check that it is consistent with the known status of the
1399 ----------------------------
1400 -- Check_Anonymous_Return --
1401 ----------------------------
1403 procedure Check_Anonymous_Return is
1408 if Present (Spec_Id) then
1414 if Ekind (Scop) = E_Function
1415 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1416 and then Has_Task (Designated_Type (Etype (Scop)))
1417 and then Expander_Active
1420 Make_Object_Declaration (Loc,
1421 Defining_Identifier =>
1422 Make_Defining_Identifier (Loc, Name_uMaster),
1423 Constant_Present => True,
1424 Object_Definition =>
1425 New_Reference_To (RTE (RE_Master_Id), Loc),
1427 Make_Explicit_Dereference (Loc,
1428 New_Reference_To (RTE (RE_Current_Master), Loc)));
1430 if Present (Declarations (N)) then
1431 Prepend (Decl, Declarations (N));
1433 Set_Declarations (N, New_List (Decl));
1436 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1437 Set_Has_Master_Entity (Scop);
1439 end Check_Anonymous_Return;
1441 -------------------------
1442 -- Check_Inline_Pragma --
1443 -------------------------
1445 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1449 function Is_Inline_Pragma (N : Node_Id) return Boolean;
1450 -- True when N is a pragma Inline or Inline_Always that applies
1451 -- to this subprogram.
1453 -----------------------
1454 -- Is_Inline_Pragma --
1455 -----------------------
1457 function Is_Inline_Pragma (N : Node_Id) return Boolean is
1460 Nkind (N) = N_Pragma
1462 (Pragma_Name (N) = Name_Inline_Always
1465 and then Pragma_Name (N) = Name_Inline))
1468 (Expression (First (Pragma_Argument_Associations (N))))
1470 end Is_Inline_Pragma;
1472 -- Start of processing for Check_Inline_Pragma
1475 if not Expander_Active then
1479 if Is_List_Member (N)
1480 and then Present (Next (N))
1481 and then Is_Inline_Pragma (Next (N))
1485 elsif Nkind (N) /= N_Subprogram_Body_Stub
1486 and then Present (Declarations (N))
1487 and then Is_Inline_Pragma (First (Declarations (N)))
1489 Prag := First (Declarations (N));
1495 if Present (Prag) then
1496 if Present (Spec_Id) then
1497 if List_Containing (N) =
1498 List_Containing (Unit_Declaration_Node (Spec_Id))
1504 -- Create a subprogram declaration, to make treatment uniform
1507 Subp : constant Entity_Id :=
1508 Make_Defining_Identifier (Loc, Chars (Body_Id));
1509 Decl : constant Node_Id :=
1510 Make_Subprogram_Declaration (Loc,
1511 Specification => New_Copy_Tree (Specification (N)));
1513 Set_Defining_Unit_Name (Specification (Decl), Subp);
1515 if Present (First_Formal (Body_Id)) then
1516 Plist := Copy_Parameter_List (Body_Id);
1517 Set_Parameter_Specifications
1518 (Specification (Decl), Plist);
1521 Insert_Before (N, Decl);
1524 Set_Has_Pragma_Inline (Subp);
1526 if Pragma_Name (Prag) = Name_Inline_Always then
1527 Set_Is_Inlined (Subp);
1528 Set_Has_Pragma_Inline_Always (Subp);
1535 end Check_Inline_Pragma;
1537 -----------------------
1538 -- Disambiguate_Spec --
1539 -----------------------
1541 function Disambiguate_Spec return Entity_Id is
1542 Priv_Spec : Entity_Id;
1545 procedure Replace_Types (To_Corresponding : Boolean);
1546 -- Depending on the flag, replace the type of formal parameters of
1547 -- Body_Id if it is a concurrent type implementing interfaces with
1548 -- the corresponding record type or the other way around.
1550 procedure Replace_Types (To_Corresponding : Boolean) is
1552 Formal_Typ : Entity_Id;
1555 Formal := First_Formal (Body_Id);
1556 while Present (Formal) loop
1557 Formal_Typ := Etype (Formal);
1559 -- From concurrent type to corresponding record
1561 if To_Corresponding then
1562 if Is_Concurrent_Type (Formal_Typ)
1563 and then Present (Corresponding_Record_Type (Formal_Typ))
1564 and then Present (Interfaces (
1565 Corresponding_Record_Type (Formal_Typ)))
1568 Corresponding_Record_Type (Formal_Typ));
1571 -- From corresponding record to concurrent type
1574 if Is_Concurrent_Record_Type (Formal_Typ)
1575 and then Present (Interfaces (Formal_Typ))
1578 Corresponding_Concurrent_Type (Formal_Typ));
1582 Next_Formal (Formal);
1586 -- Start of processing for Disambiguate_Spec
1589 -- Try to retrieve the specification of the body as is. All error
1590 -- messages are suppressed because the body may not have a spec in
1591 -- its current state.
1593 Spec_N := Find_Corresponding_Spec (N, False);
1595 -- It is possible that this is the body of a primitive declared
1596 -- between a private and a full view of a concurrent type. The
1597 -- controlling parameter of the spec carries the concurrent type,
1598 -- not the corresponding record type as transformed by Analyze_
1599 -- Subprogram_Specification. In such cases, we undo the change
1600 -- made by the analysis of the specification and try to find the
1603 -- Note that wrappers already have their corresponding specs and
1604 -- bodies set during their creation, so if the candidate spec is
1605 -- a wrapper, then we definitely need to swap all types to their
1606 -- original concurrent status.
1609 or else Is_Primitive_Wrapper (Spec_N)
1611 -- Restore all references of corresponding record types to the
1612 -- original concurrent types.
1614 Replace_Types (To_Corresponding => False);
1615 Priv_Spec := Find_Corresponding_Spec (N, False);
1617 -- The current body truly belongs to a primitive declared between
1618 -- a private and a full view. We leave the modified body as is,
1619 -- and return the true spec.
1621 if Present (Priv_Spec)
1622 and then Is_Private_Primitive (Priv_Spec)
1627 -- In case that this is some sort of error, restore the original
1628 -- state of the body.
1630 Replace_Types (To_Corresponding => True);
1634 end Disambiguate_Spec;
1636 -------------------------------------
1637 -- Is_Private_Concurrent_Primitive --
1638 -------------------------------------
1640 function Is_Private_Concurrent_Primitive
1641 (Subp_Id : Entity_Id) return Boolean
1643 Formal_Typ : Entity_Id;
1646 if Present (First_Formal (Subp_Id)) then
1647 Formal_Typ := Etype (First_Formal (Subp_Id));
1649 if Is_Concurrent_Record_Type (Formal_Typ) then
1650 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
1653 -- The type of the first formal is a concurrent tagged type with
1657 Is_Concurrent_Type (Formal_Typ)
1658 and then Is_Tagged_Type (Formal_Typ)
1659 and then Has_Private_Declaration (Formal_Typ);
1663 end Is_Private_Concurrent_Primitive;
1665 ----------------------------
1666 -- Set_Trivial_Subprogram --
1667 ----------------------------
1669 procedure Set_Trivial_Subprogram (N : Node_Id) is
1670 Nxt : constant Node_Id := Next (N);
1673 Set_Is_Trivial_Subprogram (Body_Id);
1675 if Present (Spec_Id) then
1676 Set_Is_Trivial_Subprogram (Spec_Id);
1680 and then Nkind (Nxt) = N_Simple_Return_Statement
1681 and then No (Next (Nxt))
1682 and then Present (Expression (Nxt))
1683 and then Is_Entity_Name (Expression (Nxt))
1685 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
1687 end Set_Trivial_Subprogram;
1689 ---------------------------------
1690 -- Verify_Overriding_Indicator --
1691 ---------------------------------
1693 procedure Verify_Overriding_Indicator is
1695 if Must_Override (Body_Spec) then
1696 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
1697 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
1701 elsif not Is_Overriding_Operation (Spec_Id) then
1703 ("subprogram& is not overriding", Body_Spec, Spec_Id);
1706 elsif Must_Not_Override (Body_Spec) then
1707 if Is_Overriding_Operation (Spec_Id) then
1709 ("subprogram& overrides inherited operation",
1710 Body_Spec, Spec_Id);
1712 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
1713 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
1716 ("subprogram & overrides predefined operator ",
1717 Body_Spec, Spec_Id);
1719 -- If this is not a primitive operation the overriding indicator
1720 -- is altogether illegal.
1722 elsif not Is_Primitive (Spec_Id) then
1723 Error_Msg_N ("overriding indicator only allowed " &
1724 "if subprogram is primitive",
1729 and then Is_Overriding_Operation (Spec_Id)
1731 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
1732 Style.Missing_Overriding (N, Body_Id);
1734 end Verify_Overriding_Indicator;
1736 -- Start of processing for Analyze_Subprogram_Body
1739 if Debug_Flag_C then
1740 Write_Str ("==== Compiling subprogram body ");
1741 Write_Name (Chars (Body_Id));
1742 Write_Str (" from ");
1743 Write_Location (Loc);
1747 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1749 -- Generic subprograms are handled separately. They always have a
1750 -- generic specification. Determine whether current scope has a
1751 -- previous declaration.
1753 -- If the subprogram body is defined within an instance of the same
1754 -- name, the instance appears as a package renaming, and will be hidden
1755 -- within the subprogram.
1757 if Present (Prev_Id)
1758 and then not Is_Overloadable (Prev_Id)
1759 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
1760 or else Comes_From_Source (Prev_Id))
1762 if Is_Generic_Subprogram (Prev_Id) then
1764 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1765 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1767 Analyze_Generic_Subprogram_Body (N, Spec_Id);
1771 -- Previous entity conflicts with subprogram name. Attempting to
1772 -- enter name will post error.
1774 Enter_Name (Body_Id);
1778 -- Non-generic case, find the subprogram declaration, if one was seen,
1779 -- or enter new overloaded entity in the current scope. If the
1780 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
1781 -- part of the context of one of its subunits. No need to redo the
1784 elsif Prev_Id = Body_Id
1785 and then Has_Completion (Body_Id)
1790 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
1792 if Nkind (N) = N_Subprogram_Body_Stub
1793 or else No (Corresponding_Spec (N))
1795 if Is_Private_Concurrent_Primitive (Body_Id) then
1796 Spec_Id := Disambiguate_Spec;
1798 Spec_Id := Find_Corresponding_Spec (N);
1801 -- If this is a duplicate body, no point in analyzing it
1803 if Error_Posted (N) then
1807 -- A subprogram body should cause freezing of its own declaration,
1808 -- but if there was no previous explicit declaration, then the
1809 -- subprogram will get frozen too late (there may be code within
1810 -- the body that depends on the subprogram having been frozen,
1811 -- such as uses of extra formals), so we force it to be frozen
1812 -- here. Same holds if the body and spec are compilation units.
1813 -- Finally, if the return type is an anonymous access to protected
1814 -- subprogram, it must be frozen before the body because its
1815 -- expansion has generated an equivalent type that is used when
1816 -- elaborating the body.
1818 if No (Spec_Id) then
1819 Freeze_Before (N, Body_Id);
1821 elsif Nkind (Parent (N)) = N_Compilation_Unit then
1822 Freeze_Before (N, Spec_Id);
1824 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
1825 Freeze_Before (N, Etype (Body_Id));
1829 Spec_Id := Corresponding_Spec (N);
1833 -- Do not inline any subprogram that contains nested subprograms, since
1834 -- the backend inlining circuit seems to generate uninitialized
1835 -- references in this case. We know this happens in the case of front
1836 -- end ZCX support, but it also appears it can happen in other cases as
1837 -- well. The backend often rejects attempts to inline in the case of
1838 -- nested procedures anyway, so little if anything is lost by this.
1839 -- Note that this is test is for the benefit of the back-end. There is
1840 -- a separate test for front-end inlining that also rejects nested
1843 -- Do not do this test if errors have been detected, because in some
1844 -- error cases, this code blows up, and we don't need it anyway if
1845 -- there have been errors, since we won't get to the linker anyway.
1847 if Comes_From_Source (Body_Id)
1848 and then Serious_Errors_Detected = 0
1852 P_Ent := Scope (P_Ent);
1853 exit when No (P_Ent) or else P_Ent = Standard_Standard;
1855 if Is_Subprogram (P_Ent) then
1856 Set_Is_Inlined (P_Ent, False);
1858 if Comes_From_Source (P_Ent)
1859 and then Has_Pragma_Inline (P_Ent)
1862 ("cannot inline& (nested subprogram)?",
1869 Check_Inline_Pragma (Spec_Id);
1871 -- Case of fully private operation in the body of the protected type.
1872 -- We must create a declaration for the subprogram, in order to attach
1873 -- the protected subprogram that will be used in internal calls.
1876 and then Comes_From_Source (N)
1877 and then Is_Protected_Type (Current_Scope)
1886 Formal := First_Formal (Body_Id);
1888 -- The protected operation always has at least one formal, namely
1889 -- the object itself, but it is only placed in the parameter list
1890 -- if expansion is enabled.
1893 or else Expander_Active
1895 Plist := Copy_Parameter_List (Body_Id);
1900 if Nkind (Body_Spec) = N_Procedure_Specification then
1902 Make_Procedure_Specification (Loc,
1903 Defining_Unit_Name =>
1904 Make_Defining_Identifier (Sloc (Body_Id),
1905 Chars => Chars (Body_Id)),
1906 Parameter_Specifications => Plist);
1909 Make_Function_Specification (Loc,
1910 Defining_Unit_Name =>
1911 Make_Defining_Identifier (Sloc (Body_Id),
1912 Chars => Chars (Body_Id)),
1913 Parameter_Specifications => Plist,
1914 Result_Definition =>
1915 New_Occurrence_Of (Etype (Body_Id), Loc));
1919 Make_Subprogram_Declaration (Loc,
1920 Specification => New_Spec);
1921 Insert_Before (N, Decl);
1922 Spec_Id := Defining_Unit_Name (New_Spec);
1924 -- Indicate that the entity comes from source, to ensure that
1925 -- cross-reference information is properly generated. The body
1926 -- itself is rewritten during expansion, and the body entity will
1927 -- not appear in calls to the operation.
1929 Set_Comes_From_Source (Spec_Id, True);
1931 Set_Has_Completion (Spec_Id);
1932 Set_Convention (Spec_Id, Convention_Protected);
1935 elsif Present (Spec_Id) then
1936 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1937 Verify_Overriding_Indicator;
1939 -- In general, the spec will be frozen when we start analyzing the
1940 -- body. However, for internally generated operations, such as
1941 -- wrapper functions for inherited operations with controlling
1942 -- results, the spec may not have been frozen by the time we
1943 -- expand the freeze actions that include the bodies. In particular,
1944 -- extra formals for accessibility or for return-in-place may need
1945 -- to be generated. Freeze nodes, if any, are inserted before the
1948 if not Is_Frozen (Spec_Id)
1949 and then Expander_Active
1951 -- Force the generation of its freezing node to ensure proper
1952 -- management of access types in the backend.
1954 -- This is definitely needed for some cases, but it is not clear
1955 -- why, to be investigated further???
1957 Set_Has_Delayed_Freeze (Spec_Id);
1958 Insert_Actions (N, Freeze_Entity (Spec_Id, Loc));
1962 if Chars (Body_Id) = Name_uPostconditions then
1963 Set_Has_Postconditions (Current_Scope);
1966 -- Place subprogram on scope stack, and make formals visible. If there
1967 -- is a spec, the visible entity remains that of the spec.
1969 if Present (Spec_Id) then
1970 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1972 if Is_Child_Unit (Spec_Id) then
1973 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
1977 Style.Check_Identifier (Body_Id, Spec_Id);
1980 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1981 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1983 if Is_Abstract_Subprogram (Spec_Id) then
1984 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1988 Set_Convention (Body_Id, Convention (Spec_Id));
1989 Set_Has_Completion (Spec_Id);
1991 if Is_Protected_Type (Scope (Spec_Id)) then
1992 Prot_Typ := Scope (Spec_Id);
1995 -- If this is a body generated for a renaming, do not check for
1996 -- full conformance. The check is redundant, because the spec of
1997 -- the body is a copy of the spec in the renaming declaration,
1998 -- and the test can lead to spurious errors on nested defaults.
2000 if Present (Spec_Decl)
2001 and then not Comes_From_Source (N)
2003 (Nkind (Original_Node (Spec_Decl)) =
2004 N_Subprogram_Renaming_Declaration
2005 or else (Present (Corresponding_Body (Spec_Decl))
2007 Nkind (Unit_Declaration_Node
2008 (Corresponding_Body (Spec_Decl))) =
2009 N_Subprogram_Renaming_Declaration))
2016 Fully_Conformant, True, Conformant, Body_Id);
2019 -- If the body is not fully conformant, we have to decide if we
2020 -- should analyze it or not. If it has a really messed up profile
2021 -- then we probably should not analyze it, since we will get too
2022 -- many bogus messages.
2024 -- Our decision is to go ahead in the non-fully conformant case
2025 -- only if it is at least mode conformant with the spec. Note
2026 -- that the call to Check_Fully_Conformant has issued the proper
2027 -- error messages to complain about the lack of conformance.
2030 and then not Mode_Conformant (Body_Id, Spec_Id)
2036 if Spec_Id /= Body_Id then
2037 Reference_Body_Formals (Spec_Id, Body_Id);
2040 if Nkind (N) /= N_Subprogram_Body_Stub then
2041 Set_Corresponding_Spec (N, Spec_Id);
2043 -- Ada 2005 (AI-345): If the operation is a primitive operation
2044 -- of a concurrent type, the type of the first parameter has been
2045 -- replaced with the corresponding record, which is the proper
2046 -- run-time structure to use. However, within the body there may
2047 -- be uses of the formals that depend on primitive operations
2048 -- of the type (in particular calls in prefixed form) for which
2049 -- we need the original concurrent type. The operation may have
2050 -- several controlling formals, so the replacement must be done
2053 if Comes_From_Source (Spec_Id)
2054 and then Present (First_Entity (Spec_Id))
2055 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2056 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2058 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2061 (Corresponding_Concurrent_Type
2062 (Etype (First_Entity (Spec_Id))))
2065 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2069 Form := First_Formal (Spec_Id);
2070 while Present (Form) loop
2071 if Etype (Form) = Typ then
2072 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2080 -- Make the formals visible, and place subprogram on scope stack.
2081 -- This is also the point at which we set Last_Real_Spec_Entity
2082 -- to mark the entities which will not be moved to the body.
2084 Install_Formals (Spec_Id);
2085 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2086 Push_Scope (Spec_Id);
2088 -- Make sure that the subprogram is immediately visible. For
2089 -- child units that have no separate spec this is indispensable.
2090 -- Otherwise it is safe albeit redundant.
2092 Set_Is_Immediately_Visible (Spec_Id);
2095 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2096 Set_Ekind (Body_Id, E_Subprogram_Body);
2097 Set_Scope (Body_Id, Scope (Spec_Id));
2098 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2100 -- Case of subprogram body with no previous spec
2104 and then Comes_From_Source (Body_Id)
2105 and then not Suppress_Style_Checks (Body_Id)
2106 and then not In_Instance
2108 Style.Body_With_No_Spec (N);
2111 New_Overloaded_Entity (Body_Id);
2113 if Nkind (N) /= N_Subprogram_Body_Stub then
2114 Set_Acts_As_Spec (N);
2115 Generate_Definition (Body_Id);
2117 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2118 Generate_Reference_To_Formals (Body_Id);
2119 Install_Formals (Body_Id);
2120 Push_Scope (Body_Id);
2124 -- If the return type is an anonymous access type whose designated type
2125 -- is the limited view of a class-wide type and the non-limited view is
2126 -- available, update the return type accordingly.
2128 if Ada_Version >= Ada_05
2129 and then Comes_From_Source (N)
2136 Rtyp := Etype (Current_Scope);
2138 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2139 Etyp := Directly_Designated_Type (Rtyp);
2141 if Is_Class_Wide_Type (Etyp)
2142 and then From_With_Type (Etyp)
2144 Set_Directly_Designated_Type
2145 (Etype (Current_Scope), Available_View (Etyp));
2151 -- If this is the proper body of a stub, we must verify that the stub
2152 -- conforms to the body, and to the previous spec if one was present.
2153 -- we know already that the body conforms to that spec. This test is
2154 -- only required for subprograms that come from source.
2156 if Nkind (Parent (N)) = N_Subunit
2157 and then Comes_From_Source (N)
2158 and then not Error_Posted (Body_Id)
2159 and then Nkind (Corresponding_Stub (Parent (N))) =
2160 N_Subprogram_Body_Stub
2163 Old_Id : constant Entity_Id :=
2165 (Specification (Corresponding_Stub (Parent (N))));
2167 Conformant : Boolean := False;
2170 if No (Spec_Id) then
2171 Check_Fully_Conformant (Body_Id, Old_Id);
2175 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2177 if not Conformant then
2179 -- The stub was taken to be a new declaration. Indicate
2180 -- that it lacks a body.
2182 Set_Has_Completion (Old_Id, False);
2188 Set_Has_Completion (Body_Id);
2189 Check_Eliminated (Body_Id);
2191 if Nkind (N) = N_Subprogram_Body_Stub then
2194 elsif Present (Spec_Id)
2195 and then Expander_Active
2197 (Has_Pragma_Inline_Always (Spec_Id)
2198 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2200 Build_Body_To_Inline (N, Spec_Id);
2203 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2204 -- if its specification we have to install the private withed units.
2205 -- This holds for child units as well.
2207 if Is_Compilation_Unit (Body_Id)
2208 or else Nkind (Parent (N)) = N_Compilation_Unit
2210 Install_Private_With_Clauses (Body_Id);
2213 Check_Anonymous_Return;
2215 -- Set the Protected_Formal field of each extra formal of the protected
2216 -- subprogram to reference the corresponding extra formal of the
2217 -- subprogram that implements it. For regular formals this occurs when
2218 -- the protected subprogram's declaration is expanded, but the extra
2219 -- formals don't get created until the subprogram is frozen. We need to
2220 -- do this before analyzing the protected subprogram's body so that any
2221 -- references to the original subprogram's extra formals will be changed
2222 -- refer to the implementing subprogram's formals (see Expand_Formal).
2224 if Present (Spec_Id)
2225 and then Is_Protected_Type (Scope (Spec_Id))
2226 and then Present (Protected_Body_Subprogram (Spec_Id))
2229 Impl_Subp : constant Entity_Id :=
2230 Protected_Body_Subprogram (Spec_Id);
2231 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2232 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2234 while Present (Prot_Ext_Formal) loop
2235 pragma Assert (Present (Impl_Ext_Formal));
2236 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2237 Next_Formal_With_Extras (Prot_Ext_Formal);
2238 Next_Formal_With_Extras (Impl_Ext_Formal);
2243 -- Now we can go on to analyze the body
2245 HSS := Handled_Statement_Sequence (N);
2246 Set_Actual_Subtypes (N, Current_Scope);
2248 -- Deal with preconditions and postconditions
2250 Process_PPCs (N, Spec_Id, Body_Id);
2252 -- Add a declaration for the Protection object, renaming declarations
2253 -- for discriminals and privals and finally a declaration for the entry
2254 -- family index (if applicable). This form of early expansion is done
2255 -- when the Expander is active because Install_Private_Data_Declarations
2256 -- references entities which were created during regular expansion.
2259 and then Comes_From_Source (N)
2260 and then Present (Prot_Typ)
2261 and then Present (Spec_Id)
2262 and then not Is_Eliminated (Spec_Id)
2264 Install_Private_Data_Declarations
2265 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2268 -- Analyze the declarations (this call will analyze the precondition
2269 -- Check pragmas we prepended to the list, as well as the declaration
2270 -- of the _Postconditions procedure).
2272 Analyze_Declarations (Declarations (N));
2274 -- Check completion, and analyze the statements
2277 Inspect_Deferred_Constant_Completion (Declarations (N));
2280 -- Deal with end of scope processing for the body
2282 Process_End_Label (HSS, 't', Current_Scope);
2284 Check_Subprogram_Order (N);
2285 Set_Analyzed (Body_Id);
2287 -- If we have a separate spec, then the analysis of the declarations
2288 -- caused the entities in the body to be chained to the spec id, but
2289 -- we want them chained to the body id. Only the formal parameters
2290 -- end up chained to the spec id in this case.
2292 if Present (Spec_Id) then
2294 -- We must conform to the categorization of our spec
2296 Validate_Categorization_Dependency (N, Spec_Id);
2298 -- And if this is a child unit, the parent units must conform
2300 if Is_Child_Unit (Spec_Id) then
2301 Validate_Categorization_Dependency
2302 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2305 -- Here is where we move entities from the spec to the body
2307 -- Case where there are entities that stay with the spec
2309 if Present (Last_Real_Spec_Entity) then
2311 -- No body entities (happens when the only real spec entities
2312 -- come from precondition and postcondition pragmas)
2314 if No (Last_Entity (Body_Id)) then
2316 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2318 -- Body entities present (formals), so chain stuff past them
2322 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2325 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2326 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2327 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2329 -- Case where there are no spec entities, in this case there can
2330 -- be no body entities either, so just move everything.
2333 pragma Assert (No (Last_Entity (Body_Id)));
2334 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2335 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2336 Set_First_Entity (Spec_Id, Empty);
2337 Set_Last_Entity (Spec_Id, Empty);
2341 -- If function, check return statements
2343 if Nkind (Body_Spec) = N_Function_Specification then
2348 if Present (Spec_Id) then
2354 if Return_Present (Id) then
2355 Check_Returns (HSS, 'F', Missing_Ret);
2358 Set_Has_Missing_Return (Id);
2361 elsif not Is_Machine_Code_Subprogram (Id)
2362 and then not Body_Deleted
2364 Error_Msg_N ("missing RETURN statement in function body", N);
2368 -- If procedure with No_Return, check returns
2370 elsif Nkind (Body_Spec) = N_Procedure_Specification
2371 and then Present (Spec_Id)
2372 and then No_Return (Spec_Id)
2374 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2377 -- Now we are going to check for variables that are never modified in
2378 -- the body of the procedure. But first we deal with a special case
2379 -- where we want to modify this check. If the body of the subprogram
2380 -- starts with a raise statement or its equivalent, or if the body
2381 -- consists entirely of a null statement, then it is pretty obvious
2382 -- that it is OK to not reference the parameters. For example, this
2383 -- might be the following common idiom for a stubbed function:
2384 -- statement of the procedure raises an exception. In particular this
2385 -- deals with the common idiom of a stubbed function, which might
2386 -- appear as something like
2388 -- function F (A : Integer) return Some_Type;
2391 -- raise Program_Error;
2395 -- Here the purpose of X is simply to satisfy the annoying requirement
2396 -- in Ada that there be at least one return, and we certainly do not
2397 -- want to go posting warnings on X that it is not initialized! On
2398 -- the other hand, if X is entirely unreferenced that should still
2401 -- What we do is to detect these cases, and if we find them, flag the
2402 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2403 -- suppress unwanted warnings. For the case of the function stub above
2404 -- we have a special test to set X as apparently assigned to suppress
2411 -- Skip initial labels (for one thing this occurs when we are in
2412 -- front end ZCX mode, but in any case it is irrelevant), and also
2413 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2415 Stm := First (Statements (HSS));
2416 while Nkind (Stm) = N_Label
2417 or else Nkind (Stm) in N_Push_xxx_Label
2422 -- Do the test on the original statement before expansion
2425 Ostm : constant Node_Id := Original_Node (Stm);
2428 -- If explicit raise statement, turn on flag
2430 if Nkind (Ostm) = N_Raise_Statement then
2431 Set_Trivial_Subprogram (Stm);
2433 -- If null statement, and no following statements, turn on flag
2435 elsif Nkind (Stm) = N_Null_Statement
2436 and then Comes_From_Source (Stm)
2437 and then No (Next (Stm))
2439 Set_Trivial_Subprogram (Stm);
2441 -- Check for explicit call cases which likely raise an exception
2443 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2444 if Is_Entity_Name (Name (Ostm)) then
2446 Ent : constant Entity_Id := Entity (Name (Ostm));
2449 -- If the procedure is marked No_Return, then likely it
2450 -- raises an exception, but in any case it is not coming
2451 -- back here, so turn on the flag.
2453 if Ekind (Ent) = E_Procedure
2454 and then No_Return (Ent)
2456 Set_Trivial_Subprogram (Stm);
2464 -- Check for variables that are never modified
2470 -- If there is a separate spec, then transfer Never_Set_In_Source
2471 -- flags from out parameters to the corresponding entities in the
2472 -- body. The reason we do that is we want to post error flags on
2473 -- the body entities, not the spec entities.
2475 if Present (Spec_Id) then
2476 E1 := First_Entity (Spec_Id);
2477 while Present (E1) loop
2478 if Ekind (E1) = E_Out_Parameter then
2479 E2 := First_Entity (Body_Id);
2480 while Present (E2) loop
2481 exit when Chars (E1) = Chars (E2);
2485 if Present (E2) then
2486 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2494 -- Check references in body unless it was deleted. Note that the
2495 -- check of Body_Deleted here is not just for efficiency, it is
2496 -- necessary to avoid junk warnings on formal parameters.
2498 if not Body_Deleted then
2499 Check_References (Body_Id);
2502 end Analyze_Subprogram_Body;
2504 ------------------------------------
2505 -- Analyze_Subprogram_Declaration --
2506 ------------------------------------
2508 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2509 Designator : constant Entity_Id :=
2510 Analyze_Subprogram_Specification (Specification (N));
2511 Scop : constant Entity_Id := Current_Scope;
2513 -- Start of processing for Analyze_Subprogram_Declaration
2516 Generate_Definition (Designator);
2518 -- Check for RCI unit subprogram declarations for illegal inlined
2519 -- subprograms and subprograms having access parameter or limited
2520 -- parameter without Read and Write attributes (RM E.2.3(12-13)).
2522 Validate_RCI_Subprogram_Declaration (N);
2526 Defining_Entity (N),
2527 " Analyze subprogram spec: ");
2529 if Debug_Flag_C then
2530 Write_Str ("==== Compiling subprogram spec ");
2531 Write_Name (Chars (Designator));
2532 Write_Str (" from ");
2533 Write_Location (Sloc (N));
2537 New_Overloaded_Entity (Designator);
2538 Check_Delayed_Subprogram (Designator);
2540 -- If the type of the first formal of the current subprogram is a non
2541 -- generic tagged private type , mark the subprogram as being a private
2544 if Present (First_Formal (Designator)) then
2546 Formal_Typ : constant Entity_Id :=
2547 Etype (First_Formal (Designator));
2549 Set_Is_Private_Primitive (Designator,
2550 Is_Tagged_Type (Formal_Typ)
2551 and then Is_Private_Type (Formal_Typ)
2552 and then not Is_Generic_Actual_Type (Formal_Typ));
2556 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
2559 if Ada_Version >= Ada_05
2560 and then Comes_From_Source (N)
2561 and then Is_Dispatching_Operation (Designator)
2568 if Has_Controlling_Result (Designator) then
2569 Etyp := Etype (Designator);
2572 E := First_Entity (Designator);
2574 and then Is_Formal (E)
2575 and then not Is_Controlling_Formal (E)
2583 if Is_Access_Type (Etyp) then
2584 Etyp := Directly_Designated_Type (Etyp);
2587 if Is_Interface (Etyp)
2588 and then not Is_Abstract_Subprogram (Designator)
2589 and then not (Ekind (Designator) = E_Procedure
2590 and then Null_Present (Specification (N)))
2592 Error_Msg_Name_1 := Chars (Defining_Entity (N));
2594 ("(Ada 2005) interface subprogram % must be abstract or null",
2600 -- What is the following code for, it used to be
2602 -- ??? Set_Suppress_Elaboration_Checks
2603 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
2605 -- The following seems equivalent, but a bit dubious
2607 if Elaboration_Checks_Suppressed (Designator) then
2608 Set_Kill_Elaboration_Checks (Designator);
2611 if Scop /= Standard_Standard
2612 and then not Is_Child_Unit (Designator)
2614 Set_Categorization_From_Scope (Designator, Scop);
2616 -- For a compilation unit, check for library-unit pragmas
2618 Push_Scope (Designator);
2619 Set_Categorization_From_Pragmas (N);
2620 Validate_Categorization_Dependency (N, Designator);
2624 -- For a compilation unit, set body required. This flag will only be
2625 -- reset if a valid Import or Interface pragma is processed later on.
2627 if Nkind (Parent (N)) = N_Compilation_Unit then
2628 Set_Body_Required (Parent (N), True);
2630 if Ada_Version >= Ada_05
2631 and then Nkind (Specification (N)) = N_Procedure_Specification
2632 and then Null_Present (Specification (N))
2635 ("null procedure cannot be declared at library level", N);
2639 Generate_Reference_To_Formals (Designator);
2640 Check_Eliminated (Designator);
2642 -- Ada 2005: if procedure is declared with "is null" qualifier,
2643 -- it requires no body.
2645 if Nkind (Specification (N)) = N_Procedure_Specification
2646 and then Null_Present (Specification (N))
2648 Set_Has_Completion (Designator);
2649 Set_Is_Inlined (Designator);
2651 if Is_Protected_Type (Current_Scope) then
2653 ("protected operation cannot be a null procedure", N);
2656 end Analyze_Subprogram_Declaration;
2658 --------------------------------------
2659 -- Analyze_Subprogram_Specification --
2660 --------------------------------------
2662 -- Reminder: N here really is a subprogram specification (not a subprogram
2663 -- declaration). This procedure is called to analyze the specification in
2664 -- both subprogram bodies and subprogram declarations (specs).
2666 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
2667 Designator : constant Entity_Id := Defining_Entity (N);
2668 Formals : constant List_Id := Parameter_Specifications (N);
2670 -- Start of processing for Analyze_Subprogram_Specification
2673 Generate_Definition (Designator);
2675 if Nkind (N) = N_Function_Specification then
2676 Set_Ekind (Designator, E_Function);
2677 Set_Mechanism (Designator, Default_Mechanism);
2680 Set_Ekind (Designator, E_Procedure);
2681 Set_Etype (Designator, Standard_Void_Type);
2684 -- Introduce new scope for analysis of the formals and the return type
2686 Set_Scope (Designator, Current_Scope);
2688 if Present (Formals) then
2689 Push_Scope (Designator);
2690 Process_Formals (Formals, N);
2692 -- Ada 2005 (AI-345): If this is an overriding operation of an
2693 -- inherited interface operation, and the controlling type is
2694 -- a synchronized type, replace the type with its corresponding
2695 -- record, to match the proper signature of an overriding operation.
2697 if Ada_Version >= Ada_05 then
2700 Formal_Typ : Entity_Id;
2701 Rec_Typ : Entity_Id;
2704 Formal := First_Formal (Designator);
2705 while Present (Formal) loop
2706 Formal_Typ := Etype (Formal);
2708 if Is_Concurrent_Type (Formal_Typ)
2709 and then Present (Corresponding_Record_Type (Formal_Typ))
2711 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
2713 if Present (Interfaces (Rec_Typ)) then
2714 Set_Etype (Formal, Rec_Typ);
2718 Next_Formal (Formal);
2725 elsif Nkind (N) = N_Function_Specification then
2726 Analyze_Return_Type (N);
2729 if Nkind (N) = N_Function_Specification then
2730 if Nkind (Designator) = N_Defining_Operator_Symbol then
2731 Valid_Operator_Definition (Designator);
2734 May_Need_Actuals (Designator);
2736 -- Ada 2005 (AI-251): If the return type is abstract, verify that
2737 -- the subprogram is abstract also. This does not apply to renaming
2738 -- declarations, where abstractness is inherited.
2739 -- In case of primitives associated with abstract interface types
2740 -- the check is applied later (see Analyze_Subprogram_Declaration).
2742 if Is_Abstract_Type (Etype (Designator))
2743 and then not Is_Interface (Etype (Designator))
2744 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
2745 and then Nkind (Parent (N)) /=
2746 N_Abstract_Subprogram_Declaration
2748 (Nkind (Parent (N))) /= N_Formal_Abstract_Subprogram_Declaration
2751 ("function that returns abstract type must be abstract", N);
2756 end Analyze_Subprogram_Specification;
2758 --------------------------
2759 -- Build_Body_To_Inline --
2760 --------------------------
2762 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
2763 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
2764 Original_Body : Node_Id;
2765 Body_To_Analyze : Node_Id;
2766 Max_Size : constant := 10;
2767 Stat_Count : Integer := 0;
2769 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
2770 -- Check for declarations that make inlining not worthwhile
2772 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
2773 -- Check for statements that make inlining not worthwhile: any tasking
2774 -- statement, nested at any level. Keep track of total number of
2775 -- elementary statements, as a measure of acceptable size.
2777 function Has_Pending_Instantiation return Boolean;
2778 -- If some enclosing body contains instantiations that appear before the
2779 -- corresponding generic body, the enclosing body has a freeze node so
2780 -- that it can be elaborated after the generic itself. This might
2781 -- conflict with subsequent inlinings, so that it is unsafe to try to
2782 -- inline in such a case.
2784 function Has_Single_Return return Boolean;
2785 -- In general we cannot inline functions that return unconstrained type.
2786 -- However, we can handle such functions if all return statements return
2787 -- a local variable that is the only declaration in the body of the
2788 -- function. In that case the call can be replaced by that local
2789 -- variable as is done for other inlined calls.
2791 procedure Remove_Pragmas;
2792 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
2793 -- parameter has no meaning when the body is inlined and the formals
2794 -- are rewritten. Remove it from body to inline. The analysis of the
2795 -- non-inlined body will handle the pragma properly.
2797 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
2798 -- If the body of the subprogram includes a call that returns an
2799 -- unconstrained type, the secondary stack is involved, and it
2800 -- is not worth inlining.
2802 ------------------------------
2803 -- Has_Excluded_Declaration --
2804 ------------------------------
2806 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
2809 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
2810 -- Nested subprograms make a given body ineligible for inlining, but
2811 -- we make an exception for instantiations of unchecked conversion.
2812 -- The body has not been analyzed yet, so check the name, and verify
2813 -- that the visible entity with that name is the predefined unit.
2815 -----------------------------
2816 -- Is_Unchecked_Conversion --
2817 -----------------------------
2819 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
2820 Id : constant Node_Id := Name (D);
2824 if Nkind (Id) = N_Identifier
2825 and then Chars (Id) = Name_Unchecked_Conversion
2827 Conv := Current_Entity (Id);
2829 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
2830 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
2832 Conv := Current_Entity (Selector_Name (Id));
2837 return Present (Conv)
2838 and then Is_Predefined_File_Name
2839 (Unit_File_Name (Get_Source_Unit (Conv)))
2840 and then Is_Intrinsic_Subprogram (Conv);
2841 end Is_Unchecked_Conversion;
2843 -- Start of processing for Has_Excluded_Declaration
2847 while Present (D) loop
2848 if (Nkind (D) = N_Function_Instantiation
2849 and then not Is_Unchecked_Conversion (D))
2850 or else Nkind_In (D, N_Protected_Type_Declaration,
2851 N_Package_Declaration,
2852 N_Package_Instantiation,
2854 N_Procedure_Instantiation,
2855 N_Task_Type_Declaration)
2858 ("cannot inline & (non-allowed declaration)?", D, Subp);
2866 end Has_Excluded_Declaration;
2868 ----------------------------
2869 -- Has_Excluded_Statement --
2870 ----------------------------
2872 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
2878 while Present (S) loop
2879 Stat_Count := Stat_Count + 1;
2881 if Nkind_In (S, N_Abort_Statement,
2882 N_Asynchronous_Select,
2883 N_Conditional_Entry_Call,
2884 N_Delay_Relative_Statement,
2885 N_Delay_Until_Statement,
2890 ("cannot inline & (non-allowed statement)?", S, Subp);
2893 elsif Nkind (S) = N_Block_Statement then
2894 if Present (Declarations (S))
2895 and then Has_Excluded_Declaration (Declarations (S))
2899 elsif Present (Handled_Statement_Sequence (S))
2902 (Exception_Handlers (Handled_Statement_Sequence (S)))
2904 Has_Excluded_Statement
2905 (Statements (Handled_Statement_Sequence (S))))
2910 elsif Nkind (S) = N_Case_Statement then
2911 E := First (Alternatives (S));
2912 while Present (E) loop
2913 if Has_Excluded_Statement (Statements (E)) then
2920 elsif Nkind (S) = N_If_Statement then
2921 if Has_Excluded_Statement (Then_Statements (S)) then
2925 if Present (Elsif_Parts (S)) then
2926 E := First (Elsif_Parts (S));
2927 while Present (E) loop
2928 if Has_Excluded_Statement (Then_Statements (E)) then
2935 if Present (Else_Statements (S))
2936 and then Has_Excluded_Statement (Else_Statements (S))
2941 elsif Nkind (S) = N_Loop_Statement
2942 and then Has_Excluded_Statement (Statements (S))
2951 end Has_Excluded_Statement;
2953 -------------------------------
2954 -- Has_Pending_Instantiation --
2955 -------------------------------
2957 function Has_Pending_Instantiation return Boolean is
2962 while Present (S) loop
2963 if Is_Compilation_Unit (S)
2964 or else Is_Child_Unit (S)
2967 elsif Ekind (S) = E_Package
2968 and then Has_Forward_Instantiation (S)
2977 end Has_Pending_Instantiation;
2979 ------------------------
2980 -- Has_Single_Return --
2981 ------------------------
2983 function Has_Single_Return return Boolean is
2984 Return_Statement : Node_Id := Empty;
2986 function Check_Return (N : Node_Id) return Traverse_Result;
2992 function Check_Return (N : Node_Id) return Traverse_Result is
2994 if Nkind (N) = N_Simple_Return_Statement then
2995 if Present (Expression (N))
2996 and then Is_Entity_Name (Expression (N))
2998 if No (Return_Statement) then
2999 Return_Statement := N;
3002 elsif Chars (Expression (N)) =
3003 Chars (Expression (Return_Statement))
3012 -- Expression has wrong form
3022 function Check_All_Returns is new Traverse_Func (Check_Return);
3024 -- Start of processing for Has_Single_Return
3027 return Check_All_Returns (N) = OK
3028 and then Present (Declarations (N))
3029 and then Present (First (Declarations (N)))
3030 and then Chars (Expression (Return_Statement)) =
3031 Chars (Defining_Identifier (First (Declarations (N))));
3032 end Has_Single_Return;
3034 --------------------
3035 -- Remove_Pragmas --
3036 --------------------
3038 procedure Remove_Pragmas is
3043 Decl := First (Declarations (Body_To_Analyze));
3044 while Present (Decl) loop
3047 if Nkind (Decl) = N_Pragma
3048 and then (Pragma_Name (Decl) = Name_Unreferenced
3050 Pragma_Name (Decl) = Name_Unmodified)
3059 --------------------------
3060 -- Uses_Secondary_Stack --
3061 --------------------------
3063 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3064 function Check_Call (N : Node_Id) return Traverse_Result;
3065 -- Look for function calls that return an unconstrained type
3071 function Check_Call (N : Node_Id) return Traverse_Result is
3073 if Nkind (N) = N_Function_Call
3074 and then Is_Entity_Name (Name (N))
3075 and then Is_Composite_Type (Etype (Entity (Name (N))))
3076 and then not Is_Constrained (Etype (Entity (Name (N))))
3079 ("cannot inline & (call returns unconstrained type)?",
3087 function Check_Calls is new Traverse_Func (Check_Call);
3090 return Check_Calls (Bod) = Abandon;
3091 end Uses_Secondary_Stack;
3093 -- Start of processing for Build_Body_To_Inline
3096 if Nkind (Decl) = N_Subprogram_Declaration
3097 and then Present (Body_To_Inline (Decl))
3099 return; -- Done already
3101 -- Functions that return unconstrained composite types require
3102 -- secondary stack handling, and cannot currently be inlined, unless
3103 -- all return statements return a local variable that is the first
3104 -- local declaration in the body.
3106 elsif Ekind (Subp) = E_Function
3107 and then not Is_Scalar_Type (Etype (Subp))
3108 and then not Is_Access_Type (Etype (Subp))
3109 and then not Is_Constrained (Etype (Subp))
3111 if not Has_Single_Return then
3113 ("cannot inline & (unconstrained return type)?", N, Subp);
3117 -- Ditto for functions that return controlled types, where controlled
3118 -- actions interfere in complex ways with inlining.
3120 elsif Ekind (Subp) = E_Function
3121 and then Needs_Finalization (Etype (Subp))
3124 ("cannot inline & (controlled return type)?", N, Subp);
3128 if Present (Declarations (N))
3129 and then Has_Excluded_Declaration (Declarations (N))
3134 if Present (Handled_Statement_Sequence (N)) then
3135 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3137 ("cannot inline& (exception handler)?",
3138 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3142 Has_Excluded_Statement
3143 (Statements (Handled_Statement_Sequence (N)))
3149 -- We do not inline a subprogram that is too large, unless it is
3150 -- marked Inline_Always. This pragma does not suppress the other
3151 -- checks on inlining (forbidden declarations, handlers, etc).
3153 if Stat_Count > Max_Size
3154 and then not Has_Pragma_Inline_Always (Subp)
3156 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3160 if Has_Pending_Instantiation then
3162 ("cannot inline& (forward instance within enclosing body)?",
3167 -- Within an instance, the body to inline must be treated as a nested
3168 -- generic, so that the proper global references are preserved.
3170 -- Note that we do not do this at the library level, because it is not
3171 -- needed, and furthermore this causes trouble if front end inlining
3172 -- is activated (-gnatN).
3174 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3175 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3176 Original_Body := Copy_Generic_Node (N, Empty, True);
3178 Original_Body := Copy_Separate_Tree (N);
3181 -- We need to capture references to the formals in order to substitute
3182 -- the actuals at the point of inlining, i.e. instantiation. To treat
3183 -- the formals as globals to the body to inline, we nest it within
3184 -- a dummy parameterless subprogram, declared within the real one.
3185 -- To avoid generating an internal name (which is never public, and
3186 -- which affects serial numbers of other generated names), we use
3187 -- an internal symbol that cannot conflict with user declarations.
3189 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3190 Set_Defining_Unit_Name
3191 (Specification (Original_Body),
3192 Make_Defining_Identifier (Sloc (N), Name_uParent));
3193 Set_Corresponding_Spec (Original_Body, Empty);
3195 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3197 -- Set return type of function, which is also global and does not need
3200 if Ekind (Subp) = E_Function then
3201 Set_Result_Definition (Specification (Body_To_Analyze),
3202 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3205 if No (Declarations (N)) then
3206 Set_Declarations (N, New_List (Body_To_Analyze));
3208 Append (Body_To_Analyze, Declarations (N));
3211 Expander_Mode_Save_And_Set (False);
3214 Analyze (Body_To_Analyze);
3215 Push_Scope (Defining_Entity (Body_To_Analyze));
3216 Save_Global_References (Original_Body);
3218 Remove (Body_To_Analyze);
3220 Expander_Mode_Restore;
3222 -- Restore environment if previously saved
3224 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3228 -- If secondary stk used there is no point in inlining. We have
3229 -- already issued the warning in this case, so nothing to do.
3231 if Uses_Secondary_Stack (Body_To_Analyze) then
3235 Set_Body_To_Inline (Decl, Original_Body);
3236 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3237 Set_Is_Inlined (Subp);
3238 end Build_Body_To_Inline;
3244 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3246 -- Do not emit warning if this is a predefined unit which is not
3247 -- the main unit. With validity checks enabled, some predefined
3248 -- subprograms may contain nested subprograms and become ineligible
3251 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3252 and then not In_Extended_Main_Source_Unit (Subp)
3256 elsif Has_Pragma_Inline_Always (Subp) then
3258 -- Remove last character (question mark) to make this into an error,
3259 -- because the Inline_Always pragma cannot be obeyed.
3261 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3263 elsif Ineffective_Inline_Warnings then
3264 Error_Msg_NE (Msg, N, Subp);
3268 -----------------------
3269 -- Check_Conformance --
3270 -----------------------
3272 procedure Check_Conformance
3273 (New_Id : Entity_Id;
3275 Ctype : Conformance_Type;
3277 Conforms : out Boolean;
3278 Err_Loc : Node_Id := Empty;
3279 Get_Inst : Boolean := False;
3280 Skip_Controlling_Formals : Boolean := False)
3282 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3283 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
3284 -- If Errmsg is True, then processing continues to post an error message
3285 -- for conformance error on given node. Two messages are output. The
3286 -- first message points to the previous declaration with a general "no
3287 -- conformance" message. The second is the detailed reason, supplied as
3288 -- Msg. The parameter N provide information for a possible & insertion
3289 -- in the message, and also provides the location for posting the
3290 -- message in the absence of a specified Err_Loc location.
3292 -----------------------
3293 -- Conformance_Error --
3294 -----------------------
3296 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3303 if No (Err_Loc) then
3309 Error_Msg_Sloc := Sloc (Old_Id);
3312 when Type_Conformant =>
3314 ("not type conformant with declaration#!", Enode);
3316 when Mode_Conformant =>
3317 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3319 ("not mode conformant with operation inherited#!",
3323 ("not mode conformant with declaration#!", Enode);
3326 when Subtype_Conformant =>
3327 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3329 ("not subtype conformant with operation inherited#!",
3333 ("not subtype conformant with declaration#!", Enode);
3336 when Fully_Conformant =>
3337 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3339 ("not fully conformant with operation inherited#!",
3343 ("not fully conformant with declaration#!", Enode);
3347 Error_Msg_NE (Msg, Enode, N);
3349 end Conformance_Error;
3353 Old_Type : constant Entity_Id := Etype (Old_Id);
3354 New_Type : constant Entity_Id := Etype (New_Id);
3355 Old_Formal : Entity_Id;
3356 New_Formal : Entity_Id;
3357 Access_Types_Match : Boolean;
3358 Old_Formal_Base : Entity_Id;
3359 New_Formal_Base : Entity_Id;
3361 -- Start of processing for Check_Conformance
3366 -- We need a special case for operators, since they don't appear
3369 if Ctype = Type_Conformant then
3370 if Ekind (New_Id) = E_Operator
3371 and then Operator_Matches_Spec (New_Id, Old_Id)
3377 -- If both are functions/operators, check return types conform
3379 if Old_Type /= Standard_Void_Type
3380 and then New_Type /= Standard_Void_Type
3383 -- If we are checking interface conformance we omit controlling
3384 -- arguments and result, because we are only checking the conformance
3385 -- of the remaining parameters.
3387 if Has_Controlling_Result (Old_Id)
3388 and then Has_Controlling_Result (New_Id)
3389 and then Skip_Controlling_Formals
3393 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3394 Conformance_Error ("\return type does not match!", New_Id);
3398 -- Ada 2005 (AI-231): In case of anonymous access types check the
3399 -- null-exclusion and access-to-constant attributes match.
3401 if Ada_Version >= Ada_05
3402 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3404 (Can_Never_Be_Null (Old_Type)
3405 /= Can_Never_Be_Null (New_Type)
3406 or else Is_Access_Constant (Etype (Old_Type))
3407 /= Is_Access_Constant (Etype (New_Type)))
3409 Conformance_Error ("\return type does not match!", New_Id);
3413 -- If either is a function/operator and the other isn't, error
3415 elsif Old_Type /= Standard_Void_Type
3416 or else New_Type /= Standard_Void_Type
3418 Conformance_Error ("\functions can only match functions!", New_Id);
3422 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
3423 -- If this is a renaming as body, refine error message to indicate that
3424 -- the conflict is with the original declaration. If the entity is not
3425 -- frozen, the conventions don't have to match, the one of the renamed
3426 -- entity is inherited.
3428 if Ctype >= Subtype_Conformant then
3429 if Convention (Old_Id) /= Convention (New_Id) then
3431 if not Is_Frozen (New_Id) then
3434 elsif Present (Err_Loc)
3435 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
3436 and then Present (Corresponding_Spec (Err_Loc))
3438 Error_Msg_Name_1 := Chars (New_Id);
3440 Name_Ada + Convention_Id'Pos (Convention (New_Id));
3442 Conformance_Error ("\prior declaration for% has convention %!");
3445 Conformance_Error ("\calling conventions do not match!");
3450 elsif Is_Formal_Subprogram (Old_Id)
3451 or else Is_Formal_Subprogram (New_Id)
3453 Conformance_Error ("\formal subprograms not allowed!");
3458 -- Deal with parameters
3460 -- Note: we use the entity information, rather than going directly
3461 -- to the specification in the tree. This is not only simpler, but
3462 -- absolutely necessary for some cases of conformance tests between
3463 -- operators, where the declaration tree simply does not exist!
3465 Old_Formal := First_Formal (Old_Id);
3466 New_Formal := First_Formal (New_Id);
3468 while Present (Old_Formal) and then Present (New_Formal) loop
3469 if Is_Controlling_Formal (Old_Formal)
3470 and then Is_Controlling_Formal (New_Formal)
3471 and then Skip_Controlling_Formals
3473 goto Skip_Controlling_Formal;
3476 if Ctype = Fully_Conformant then
3478 -- Names must match. Error message is more accurate if we do
3479 -- this before checking that the types of the formals match.
3481 if Chars (Old_Formal) /= Chars (New_Formal) then
3482 Conformance_Error ("\name & does not match!", New_Formal);
3484 -- Set error posted flag on new formal as well to stop
3485 -- junk cascaded messages in some cases.
3487 Set_Error_Posted (New_Formal);
3492 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
3493 -- case occurs whenever a subprogram is being renamed and one of its
3494 -- parameters imposes a null exclusion. For example:
3496 -- type T is null record;
3497 -- type Acc_T is access T;
3498 -- subtype Acc_T_Sub is Acc_T;
3500 -- procedure P (Obj : not null Acc_T_Sub); -- itype
3501 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
3504 Old_Formal_Base := Etype (Old_Formal);
3505 New_Formal_Base := Etype (New_Formal);
3508 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
3509 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
3512 Access_Types_Match := Ada_Version >= Ada_05
3514 -- Ensure that this rule is only applied when New_Id is a
3515 -- renaming of Old_Id.
3517 and then Nkind (Parent (Parent (New_Id))) =
3518 N_Subprogram_Renaming_Declaration
3519 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
3520 and then Present (Entity (Name (Parent (Parent (New_Id)))))
3521 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
3523 -- Now handle the allowed access-type case
3525 and then Is_Access_Type (Old_Formal_Base)
3526 and then Is_Access_Type (New_Formal_Base)
3528 -- The type kinds must match. The only exception occurs with
3529 -- multiple generics of the form:
3532 -- type F is private; type A is private;
3533 -- type F_Ptr is access F; type A_Ptr is access A;
3534 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
3535 -- package F_Pack is ... package A_Pack is
3536 -- package F_Inst is
3537 -- new F_Pack (A, A_Ptr, A_P);
3539 -- When checking for conformance between the parameters of A_P
3540 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
3541 -- because the compiler has transformed A_Ptr into a subtype of
3542 -- F_Ptr. We catch this case in the code below.
3544 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
3546 (Is_Generic_Type (Old_Formal_Base)
3547 and then Is_Generic_Type (New_Formal_Base)
3548 and then Is_Internal (New_Formal_Base)
3549 and then Etype (Etype (New_Formal_Base)) =
3551 and then Directly_Designated_Type (Old_Formal_Base) =
3552 Directly_Designated_Type (New_Formal_Base)
3553 and then ((Is_Itype (Old_Formal_Base)
3554 and then Can_Never_Be_Null (Old_Formal_Base))
3556 (Is_Itype (New_Formal_Base)
3557 and then Can_Never_Be_Null (New_Formal_Base)));
3559 -- Types must always match. In the visible part of an instance,
3560 -- usual overloading rules for dispatching operations apply, and
3561 -- we check base types (not the actual subtypes).
3563 if In_Instance_Visible_Part
3564 and then Is_Dispatching_Operation (New_Id)
3566 if not Conforming_Types
3567 (T1 => Base_Type (Etype (Old_Formal)),
3568 T2 => Base_Type (Etype (New_Formal)),
3570 Get_Inst => Get_Inst)
3571 and then not Access_Types_Match
3573 Conformance_Error ("\type of & does not match!", New_Formal);
3577 elsif not Conforming_Types
3578 (T1 => Old_Formal_Base,
3579 T2 => New_Formal_Base,
3581 Get_Inst => Get_Inst)
3582 and then not Access_Types_Match
3584 -- Don't give error message if old type is Any_Type. This test
3585 -- avoids some cascaded errors, e.g. in case of a bad spec.
3587 if Errmsg and then Old_Formal_Base = Any_Type then
3590 Conformance_Error ("\type of & does not match!", New_Formal);
3596 -- For mode conformance, mode must match
3598 if Ctype >= Mode_Conformant then
3599 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
3600 Conformance_Error ("\mode of & does not match!", New_Formal);
3603 -- Part of mode conformance for access types is having the same
3604 -- constant modifier.
3606 elsif Access_Types_Match
3607 and then Is_Access_Constant (Old_Formal_Base) /=
3608 Is_Access_Constant (New_Formal_Base)
3611 ("\constant modifier does not match!", New_Formal);
3616 if Ctype >= Subtype_Conformant then
3618 -- Ada 2005 (AI-231): In case of anonymous access types check
3619 -- the null-exclusion and access-to-constant attributes must
3622 if Ada_Version >= Ada_05
3623 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
3624 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
3626 (Can_Never_Be_Null (Old_Formal) /=
3627 Can_Never_Be_Null (New_Formal)
3629 Is_Access_Constant (Etype (Old_Formal)) /=
3630 Is_Access_Constant (Etype (New_Formal)))
3632 -- It is allowed to omit the null-exclusion in case of stream
3633 -- attribute subprograms. We recognize stream subprograms
3634 -- through their TSS-generated suffix.
3637 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
3639 if TSS_Name /= TSS_Stream_Read
3640 and then TSS_Name /= TSS_Stream_Write
3641 and then TSS_Name /= TSS_Stream_Input
3642 and then TSS_Name /= TSS_Stream_Output
3645 ("\type of & does not match!", New_Formal);
3652 -- Full conformance checks
3654 if Ctype = Fully_Conformant then
3656 -- We have checked already that names match
3658 if Parameter_Mode (Old_Formal) = E_In_Parameter then
3660 -- Check default expressions for in parameters
3663 NewD : constant Boolean :=
3664 Present (Default_Value (New_Formal));
3665 OldD : constant Boolean :=
3666 Present (Default_Value (Old_Formal));
3668 if NewD or OldD then
3670 -- The old default value has been analyzed because the
3671 -- current full declaration will have frozen everything
3672 -- before. The new default value has not been analyzed,
3673 -- so analyze it now before we check for conformance.
3676 Push_Scope (New_Id);
3677 Preanalyze_Spec_Expression
3678 (Default_Value (New_Formal), Etype (New_Formal));
3682 if not (NewD and OldD)
3683 or else not Fully_Conformant_Expressions
3684 (Default_Value (Old_Formal),
3685 Default_Value (New_Formal))
3688 ("\default expression for & does not match!",
3697 -- A couple of special checks for Ada 83 mode. These checks are
3698 -- skipped if either entity is an operator in package Standard,
3699 -- or if either old or new instance is not from the source program.
3701 if Ada_Version = Ada_83
3702 and then Sloc (Old_Id) > Standard_Location
3703 and then Sloc (New_Id) > Standard_Location
3704 and then Comes_From_Source (Old_Id)
3705 and then Comes_From_Source (New_Id)
3708 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
3709 New_Param : constant Node_Id := Declaration_Node (New_Formal);
3712 -- Explicit IN must be present or absent in both cases. This
3713 -- test is required only in the full conformance case.
3715 if In_Present (Old_Param) /= In_Present (New_Param)
3716 and then Ctype = Fully_Conformant
3719 ("\(Ada 83) IN must appear in both declarations",
3724 -- Grouping (use of comma in param lists) must be the same
3725 -- This is where we catch a misconformance like:
3728 -- A : Integer; B : Integer
3730 -- which are represented identically in the tree except
3731 -- for the setting of the flags More_Ids and Prev_Ids.
3733 if More_Ids (Old_Param) /= More_Ids (New_Param)
3734 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
3737 ("\grouping of & does not match!", New_Formal);
3743 -- This label is required when skipping controlling formals
3745 <<Skip_Controlling_Formal>>
3747 Next_Formal (Old_Formal);
3748 Next_Formal (New_Formal);
3751 if Present (Old_Formal) then
3752 Conformance_Error ("\too few parameters!");
3755 elsif Present (New_Formal) then
3756 Conformance_Error ("\too many parameters!", New_Formal);
3759 end Check_Conformance;
3761 -----------------------
3762 -- Check_Conventions --
3763 -----------------------
3765 procedure Check_Conventions (Typ : Entity_Id) is
3766 Ifaces_List : Elist_Id;
3768 procedure Check_Convention (Op : Entity_Id);
3769 -- Verify that the convention of inherited dispatching operation Op is
3770 -- consistent among all subprograms it overrides. In order to minimize
3771 -- the search, Search_From is utilized to designate a specific point in
3772 -- the list rather than iterating over the whole list once more.
3774 ----------------------
3775 -- Check_Convention --
3776 ----------------------
3778 procedure Check_Convention (Op : Entity_Id) is
3779 Iface_Elmt : Elmt_Id;
3780 Iface_Prim_Elmt : Elmt_Id;
3781 Iface_Prim : Entity_Id;
3784 Iface_Elmt := First_Elmt (Ifaces_List);
3785 while Present (Iface_Elmt) loop
3787 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
3788 while Present (Iface_Prim_Elmt) loop
3789 Iface_Prim := Node (Iface_Prim_Elmt);
3791 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
3792 and then Convention (Iface_Prim) /= Convention (Op)
3795 ("inconsistent conventions in primitive operations", Typ);
3797 Error_Msg_Name_1 := Chars (Op);
3798 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
3799 Error_Msg_Sloc := Sloc (Op);
3801 if Comes_From_Source (Op) then
3802 if not Is_Overriding_Operation (Op) then
3803 Error_Msg_N ("\\primitive % defined #", Typ);
3805 Error_Msg_N ("\\overriding operation % with " &
3806 "convention % defined #", Typ);
3809 else pragma Assert (Present (Alias (Op)));
3810 Error_Msg_Sloc := Sloc (Alias (Op));
3811 Error_Msg_N ("\\inherited operation % with " &
3812 "convention % defined #", Typ);
3815 Error_Msg_Name_1 := Chars (Op);
3817 Get_Convention_Name (Convention (Iface_Prim));
3818 Error_Msg_Sloc := Sloc (Iface_Prim);
3819 Error_Msg_N ("\\overridden operation % with " &
3820 "convention % defined #", Typ);
3822 -- Avoid cascading errors
3827 Next_Elmt (Iface_Prim_Elmt);
3830 Next_Elmt (Iface_Elmt);
3832 end Check_Convention;
3836 Prim_Op : Entity_Id;
3837 Prim_Op_Elmt : Elmt_Id;
3839 -- Start of processing for Check_Conventions
3842 if not Has_Interfaces (Typ) then
3846 Collect_Interfaces (Typ, Ifaces_List);
3848 -- The algorithm checks every overriding dispatching operation against
3849 -- all the corresponding overridden dispatching operations, detecting
3850 -- differences in conventions.
3852 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
3853 while Present (Prim_Op_Elmt) loop
3854 Prim_Op := Node (Prim_Op_Elmt);
3856 -- A small optimization: skip the predefined dispatching operations
3857 -- since they always have the same convention.
3859 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
3860 Check_Convention (Prim_Op);
3863 Next_Elmt (Prim_Op_Elmt);
3865 end Check_Conventions;
3867 ------------------------------
3868 -- Check_Delayed_Subprogram --
3869 ------------------------------
3871 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
3874 procedure Possible_Freeze (T : Entity_Id);
3875 -- T is the type of either a formal parameter or of the return type.
3876 -- If T is not yet frozen and needs a delayed freeze, then the
3877 -- subprogram itself must be delayed.
3879 ---------------------
3880 -- Possible_Freeze --
3881 ---------------------
3883 procedure Possible_Freeze (T : Entity_Id) is
3885 if Has_Delayed_Freeze (T)
3886 and then not Is_Frozen (T)
3888 Set_Has_Delayed_Freeze (Designator);
3890 elsif Is_Access_Type (T)
3891 and then Has_Delayed_Freeze (Designated_Type (T))
3892 and then not Is_Frozen (Designated_Type (T))
3894 Set_Has_Delayed_Freeze (Designator);
3896 end Possible_Freeze;
3898 -- Start of processing for Check_Delayed_Subprogram
3901 -- Never need to freeze abstract subprogram
3903 if Ekind (Designator) /= E_Subprogram_Type
3904 and then Is_Abstract_Subprogram (Designator)
3908 -- Need delayed freeze if return type itself needs a delayed
3909 -- freeze and is not yet frozen.
3911 Possible_Freeze (Etype (Designator));
3912 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
3914 -- Need delayed freeze if any of the formal types themselves need
3915 -- a delayed freeze and are not yet frozen.
3917 F := First_Formal (Designator);
3918 while Present (F) loop
3919 Possible_Freeze (Etype (F));
3920 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
3925 -- Mark functions that return by reference. Note that it cannot be
3926 -- done for delayed_freeze subprograms because the underlying
3927 -- returned type may not be known yet (for private types)
3929 if not Has_Delayed_Freeze (Designator)
3930 and then Expander_Active
3933 Typ : constant Entity_Id := Etype (Designator);
3934 Utyp : constant Entity_Id := Underlying_Type (Typ);
3937 if Is_Inherently_Limited_Type (Typ) then
3938 Set_Returns_By_Ref (Designator);
3940 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
3941 Set_Returns_By_Ref (Designator);
3945 end Check_Delayed_Subprogram;
3947 ------------------------------------
3948 -- Check_Discriminant_Conformance --
3949 ------------------------------------
3951 procedure Check_Discriminant_Conformance
3956 Old_Discr : Entity_Id := First_Discriminant (Prev);
3957 New_Discr : Node_Id := First (Discriminant_Specifications (N));
3958 New_Discr_Id : Entity_Id;
3959 New_Discr_Type : Entity_Id;
3961 procedure Conformance_Error (Msg : String; N : Node_Id);
3962 -- Post error message for conformance error on given node. Two messages
3963 -- are output. The first points to the previous declaration with a
3964 -- general "no conformance" message. The second is the detailed reason,
3965 -- supplied as Msg. The parameter N provide information for a possible
3966 -- & insertion in the message.
3968 -----------------------
3969 -- Conformance_Error --
3970 -----------------------
3972 procedure Conformance_Error (Msg : String; N : Node_Id) is
3974 Error_Msg_Sloc := Sloc (Prev_Loc);
3975 Error_Msg_N ("not fully conformant with declaration#!", N);
3976 Error_Msg_NE (Msg, N, N);
3977 end Conformance_Error;
3979 -- Start of processing for Check_Discriminant_Conformance
3982 while Present (Old_Discr) and then Present (New_Discr) loop
3984 New_Discr_Id := Defining_Identifier (New_Discr);
3986 -- The subtype mark of the discriminant on the full type has not
3987 -- been analyzed so we do it here. For an access discriminant a new
3990 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
3992 Access_Definition (N, Discriminant_Type (New_Discr));
3995 Analyze (Discriminant_Type (New_Discr));
3996 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
3999 if not Conforming_Types
4000 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
4002 Conformance_Error ("type of & does not match!", New_Discr_Id);
4005 -- Treat the new discriminant as an occurrence of the old one,
4006 -- for navigation purposes, and fill in some semantic
4007 -- information, for completeness.
4009 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
4010 Set_Etype (New_Discr_Id, Etype (Old_Discr));
4011 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4016 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4017 Conformance_Error ("name & does not match!", New_Discr_Id);
4021 -- Default expressions must match
4024 NewD : constant Boolean :=
4025 Present (Expression (New_Discr));
4026 OldD : constant Boolean :=
4027 Present (Expression (Parent (Old_Discr)));
4030 if NewD or OldD then
4032 -- The old default value has been analyzed and expanded,
4033 -- because the current full declaration will have frozen
4034 -- everything before. The new default values have not been
4035 -- expanded, so expand now to check conformance.
4038 Preanalyze_Spec_Expression
4039 (Expression (New_Discr), New_Discr_Type);
4042 if not (NewD and OldD)
4043 or else not Fully_Conformant_Expressions
4044 (Expression (Parent (Old_Discr)),
4045 Expression (New_Discr))
4049 ("default expression for & does not match!",
4056 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4058 if Ada_Version = Ada_83 then
4060 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4063 -- Grouping (use of comma in param lists) must be the same
4064 -- This is where we catch a misconformance like:
4067 -- A : Integer; B : Integer
4069 -- which are represented identically in the tree except
4070 -- for the setting of the flags More_Ids and Prev_Ids.
4072 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4073 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4076 ("grouping of & does not match!", New_Discr_Id);
4082 Next_Discriminant (Old_Discr);
4086 if Present (Old_Discr) then
4087 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4090 elsif Present (New_Discr) then
4092 ("too many discriminants!", Defining_Identifier (New_Discr));
4095 end Check_Discriminant_Conformance;
4097 ----------------------------
4098 -- Check_Fully_Conformant --
4099 ----------------------------
4101 procedure Check_Fully_Conformant
4102 (New_Id : Entity_Id;
4104 Err_Loc : Node_Id := Empty)
4107 pragma Warnings (Off, Result);
4110 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4111 end Check_Fully_Conformant;
4113 ---------------------------
4114 -- Check_Mode_Conformant --
4115 ---------------------------
4117 procedure Check_Mode_Conformant
4118 (New_Id : Entity_Id;
4120 Err_Loc : Node_Id := Empty;
4121 Get_Inst : Boolean := False)
4124 pragma Warnings (Off, Result);
4127 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4128 end Check_Mode_Conformant;
4130 --------------------------------
4131 -- Check_Overriding_Indicator --
4132 --------------------------------
4134 procedure Check_Overriding_Indicator
4136 Overridden_Subp : Entity_Id;
4137 Is_Primitive : Boolean)
4143 -- No overriding indicator for literals
4145 if Ekind (Subp) = E_Enumeration_Literal then
4148 elsif Ekind (Subp) = E_Entry then
4149 Decl := Parent (Subp);
4152 Decl := Unit_Declaration_Node (Subp);
4155 if Nkind_In (Decl, N_Subprogram_Body,
4156 N_Subprogram_Body_Stub,
4157 N_Subprogram_Declaration,
4158 N_Abstract_Subprogram_Declaration,
4159 N_Subprogram_Renaming_Declaration)
4161 Spec := Specification (Decl);
4163 elsif Nkind (Decl) = N_Entry_Declaration then
4170 if Present (Overridden_Subp) then
4171 if Must_Not_Override (Spec) then
4172 Error_Msg_Sloc := Sloc (Overridden_Subp);
4174 if Ekind (Subp) = E_Entry then
4176 ("entry & overrides inherited operation #", Spec, Subp);
4179 ("subprogram & overrides inherited operation #", Spec, Subp);
4182 elsif Is_Subprogram (Subp) then
4183 Set_Is_Overriding_Operation (Subp);
4186 if Style_Check and then not Must_Override (Spec) then
4187 Style.Missing_Overriding (Decl, Subp);
4190 -- If Subp is an operator, it may override a predefined operation.
4191 -- In that case overridden_subp is empty because of our implicit
4192 -- representation for predefined operators. We have to check whether the
4193 -- signature of Subp matches that of a predefined operator. Note that
4194 -- first argument provides the name of the operator, and the second
4195 -- argument the signature that may match that of a standard operation.
4196 -- If the indicator is overriding, then the operator must match a
4197 -- predefined signature, because we know already that there is no
4198 -- explicit overridden operation.
4200 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
4202 if Must_Not_Override (Spec) then
4203 if not Is_Primitive then
4205 ("overriding indicator only allowed "
4206 & "if subprogram is primitive", Subp);
4208 elsif Operator_Matches_Spec (Subp, Subp) then
4210 ("subprogram & overrides predefined operator ", Spec, Subp);
4213 elsif Must_Override (Spec) then
4214 if Is_Overriding_Operation (Subp) then
4215 Set_Is_Overriding_Operation (Subp);
4217 elsif not Operator_Matches_Spec (Subp, Subp) then
4218 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
4221 elsif not Error_Posted (Subp)
4222 and then Style_Check
4223 and then Operator_Matches_Spec (Subp, Subp)
4225 not Is_Predefined_File_Name
4226 (Unit_File_Name (Get_Source_Unit (Subp)))
4228 Set_Is_Overriding_Operation (Subp);
4229 Style.Missing_Overriding (Decl, Subp);
4232 elsif Must_Override (Spec) then
4233 if Ekind (Subp) = E_Entry then
4234 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
4236 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
4239 -- If the operation is marked "not overriding" and it's not primitive
4240 -- then an error is issued, unless this is an operation of a task or
4241 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
4242 -- has been specified have already been checked above.
4244 elsif Must_Not_Override (Spec)
4245 and then not Is_Primitive
4246 and then Ekind (Subp) /= E_Entry
4247 and then Ekind (Scope (Subp)) /= E_Protected_Type
4250 ("overriding indicator only allowed if subprogram is primitive",
4254 end Check_Overriding_Indicator;
4260 -- Note: this procedure needs to know far too much about how the expander
4261 -- messes with exceptions. The use of the flag Exception_Junk and the
4262 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
4263 -- works, but is not very clean. It would be better if the expansion
4264 -- routines would leave Original_Node working nicely, and we could use
4265 -- Original_Node here to ignore all the peculiar expander messing ???
4267 procedure Check_Returns
4271 Proc : Entity_Id := Empty)
4275 procedure Check_Statement_Sequence (L : List_Id);
4276 -- Internal recursive procedure to check a list of statements for proper
4277 -- termination by a return statement (or a transfer of control or a
4278 -- compound statement that is itself internally properly terminated).
4280 ------------------------------
4281 -- Check_Statement_Sequence --
4282 ------------------------------
4284 procedure Check_Statement_Sequence (L : List_Id) is
4289 Raise_Exception_Call : Boolean;
4290 -- Set True if statement sequence terminated by Raise_Exception call
4291 -- or a Reraise_Occurrence call.
4294 Raise_Exception_Call := False;
4296 -- Get last real statement
4298 Last_Stm := Last (L);
4300 -- Deal with digging out exception handler statement sequences that
4301 -- have been transformed by the local raise to goto optimization.
4302 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
4303 -- optimization has occurred, we are looking at something like:
4306 -- original stmts in block
4310 -- goto L1; | omitted if No_Exception_Propagation
4315 -- goto L3; -- skip handler when exception not raised
4317 -- <<L1>> -- target label for local exception
4331 -- and what we have to do is to dig out the estmts1 and estmts2
4332 -- sequences (which were the original sequences of statements in
4333 -- the exception handlers) and check them.
4335 if Nkind (Last_Stm) = N_Label
4336 and then Exception_Junk (Last_Stm)
4342 exit when Nkind (Stm) /= N_Block_Statement;
4343 exit when not Exception_Junk (Stm);
4346 exit when Nkind (Stm) /= N_Label;
4347 exit when not Exception_Junk (Stm);
4348 Check_Statement_Sequence
4349 (Statements (Handled_Statement_Sequence (Next (Stm))));
4354 exit when Nkind (Stm) /= N_Goto_Statement;
4355 exit when not Exception_Junk (Stm);
4359 -- Don't count pragmas
4361 while Nkind (Last_Stm) = N_Pragma
4363 -- Don't count call to SS_Release (can happen after Raise_Exception)
4366 (Nkind (Last_Stm) = N_Procedure_Call_Statement
4368 Nkind (Name (Last_Stm)) = N_Identifier
4370 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
4372 -- Don't count exception junk
4375 (Nkind_In (Last_Stm, N_Goto_Statement,
4377 N_Object_Declaration)
4378 and then Exception_Junk (Last_Stm))
4379 or else Nkind (Last_Stm) in N_Push_xxx_Label
4380 or else Nkind (Last_Stm) in N_Pop_xxx_Label
4385 -- Here we have the "real" last statement
4387 Kind := Nkind (Last_Stm);
4389 -- Transfer of control, OK. Note that in the No_Return procedure
4390 -- case, we already diagnosed any explicit return statements, so
4391 -- we can treat them as OK in this context.
4393 if Is_Transfer (Last_Stm) then
4396 -- Check cases of explicit non-indirect procedure calls
4398 elsif Kind = N_Procedure_Call_Statement
4399 and then Is_Entity_Name (Name (Last_Stm))
4401 -- Check call to Raise_Exception procedure which is treated
4402 -- specially, as is a call to Reraise_Occurrence.
4404 -- We suppress the warning in these cases since it is likely that
4405 -- the programmer really does not expect to deal with the case
4406 -- of Null_Occurrence, and thus would find a warning about a
4407 -- missing return curious, and raising Program_Error does not
4408 -- seem such a bad behavior if this does occur.
4410 -- Note that in the Ada 2005 case for Raise_Exception, the actual
4411 -- behavior will be to raise Constraint_Error (see AI-329).
4413 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
4415 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
4417 Raise_Exception_Call := True;
4419 -- For Raise_Exception call, test first argument, if it is
4420 -- an attribute reference for a 'Identity call, then we know
4421 -- that the call cannot possibly return.
4424 Arg : constant Node_Id :=
4425 Original_Node (First_Actual (Last_Stm));
4427 if Nkind (Arg) = N_Attribute_Reference
4428 and then Attribute_Name (Arg) = Name_Identity
4435 -- If statement, need to look inside if there is an else and check
4436 -- each constituent statement sequence for proper termination.
4438 elsif Kind = N_If_Statement
4439 and then Present (Else_Statements (Last_Stm))
4441 Check_Statement_Sequence (Then_Statements (Last_Stm));
4442 Check_Statement_Sequence (Else_Statements (Last_Stm));
4444 if Present (Elsif_Parts (Last_Stm)) then
4446 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
4449 while Present (Elsif_Part) loop
4450 Check_Statement_Sequence (Then_Statements (Elsif_Part));
4458 -- Case statement, check each case for proper termination
4460 elsif Kind = N_Case_Statement then
4464 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
4465 while Present (Case_Alt) loop
4466 Check_Statement_Sequence (Statements (Case_Alt));
4467 Next_Non_Pragma (Case_Alt);
4473 -- Block statement, check its handled sequence of statements
4475 elsif Kind = N_Block_Statement then
4481 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
4490 -- Loop statement. If there is an iteration scheme, we can definitely
4491 -- fall out of the loop. Similarly if there is an exit statement, we
4492 -- can fall out. In either case we need a following return.
4494 elsif Kind = N_Loop_Statement then
4495 if Present (Iteration_Scheme (Last_Stm))
4496 or else Has_Exit (Entity (Identifier (Last_Stm)))
4500 -- A loop with no exit statement or iteration scheme is either
4501 -- an infinite loop, or it has some other exit (raise/return).
4502 -- In either case, no warning is required.
4508 -- Timed entry call, check entry call and delay alternatives
4510 -- Note: in expanded code, the timed entry call has been converted
4511 -- to a set of expanded statements on which the check will work
4512 -- correctly in any case.
4514 elsif Kind = N_Timed_Entry_Call then
4516 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4517 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
4520 -- If statement sequence of entry call alternative is missing,
4521 -- then we can definitely fall through, and we post the error
4522 -- message on the entry call alternative itself.
4524 if No (Statements (ECA)) then
4527 -- If statement sequence of delay alternative is missing, then
4528 -- we can definitely fall through, and we post the error
4529 -- message on the delay alternative itself.
4531 -- Note: if both ECA and DCA are missing the return, then we
4532 -- post only one message, should be enough to fix the bugs.
4533 -- If not we will get a message next time on the DCA when the
4536 elsif No (Statements (DCA)) then
4539 -- Else check both statement sequences
4542 Check_Statement_Sequence (Statements (ECA));
4543 Check_Statement_Sequence (Statements (DCA));
4548 -- Conditional entry call, check entry call and else part
4550 -- Note: in expanded code, the conditional entry call has been
4551 -- converted to a set of expanded statements on which the check
4552 -- will work correctly in any case.
4554 elsif Kind = N_Conditional_Entry_Call then
4556 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4559 -- If statement sequence of entry call alternative is missing,
4560 -- then we can definitely fall through, and we post the error
4561 -- message on the entry call alternative itself.
4563 if No (Statements (ECA)) then
4566 -- Else check statement sequence and else part
4569 Check_Statement_Sequence (Statements (ECA));
4570 Check_Statement_Sequence (Else_Statements (Last_Stm));
4576 -- If we fall through, issue appropriate message
4579 if not Raise_Exception_Call then
4581 ("?RETURN statement missing following this statement!",
4584 ("\?Program_Error may be raised at run time!",
4588 -- Note: we set Err even though we have not issued a warning
4589 -- because we still have a case of a missing return. This is
4590 -- an extremely marginal case, probably will never be noticed
4591 -- but we might as well get it right.
4595 -- Otherwise we have the case of a procedure marked No_Return
4598 if not Raise_Exception_Call then
4600 ("?implied return after this statement " &
4601 "will raise Program_Error",
4604 ("\?procedure & is marked as No_Return!",
4609 RE : constant Node_Id :=
4610 Make_Raise_Program_Error (Sloc (Last_Stm),
4611 Reason => PE_Implicit_Return);
4613 Insert_After (Last_Stm, RE);
4617 end Check_Statement_Sequence;
4619 -- Start of processing for Check_Returns
4623 Check_Statement_Sequence (Statements (HSS));
4625 if Present (Exception_Handlers (HSS)) then
4626 Handler := First_Non_Pragma (Exception_Handlers (HSS));
4627 while Present (Handler) loop
4628 Check_Statement_Sequence (Statements (Handler));
4629 Next_Non_Pragma (Handler);
4634 ----------------------------
4635 -- Check_Subprogram_Order --
4636 ----------------------------
4638 procedure Check_Subprogram_Order (N : Node_Id) is
4640 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
4641 -- This is used to check if S1 > S2 in the sense required by this
4642 -- test, for example nameab < namec, but name2 < name10.
4644 -----------------------------
4645 -- Subprogram_Name_Greater --
4646 -----------------------------
4648 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
4653 -- Remove trailing numeric parts
4656 while S1 (L1) in '0' .. '9' loop
4661 while S2 (L2) in '0' .. '9' loop
4665 -- If non-numeric parts non-equal, that's decisive
4667 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
4670 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
4673 -- If non-numeric parts equal, compare suffixed numeric parts. Note
4674 -- that a missing suffix is treated as numeric zero in this test.
4678 while L1 < S1'Last loop
4680 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
4684 while L2 < S2'Last loop
4686 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
4691 end Subprogram_Name_Greater;
4693 -- Start of processing for Check_Subprogram_Order
4696 -- Check body in alpha order if this is option
4699 and then Style_Check_Order_Subprograms
4700 and then Nkind (N) = N_Subprogram_Body
4701 and then Comes_From_Source (N)
4702 and then In_Extended_Main_Source_Unit (N)
4706 renames Scope_Stack.Table
4707 (Scope_Stack.Last).Last_Subprogram_Name;
4709 Body_Id : constant Entity_Id :=
4710 Defining_Entity (Specification (N));
4713 Get_Decoded_Name_String (Chars (Body_Id));
4716 if Subprogram_Name_Greater
4717 (LSN.all, Name_Buffer (1 .. Name_Len))
4719 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
4725 LSN := new String'(Name_Buffer (1 .. Name_Len));
4728 end Check_Subprogram_Order;
4730 ------------------------------
4731 -- Check_Subtype_Conformant --
4732 ------------------------------
4734 procedure Check_Subtype_Conformant
4735 (New_Id : Entity_Id;
4737 Err_Loc : Node_Id := Empty;
4738 Skip_Controlling_Formals : Boolean := False)
4741 pragma Warnings (Off, Result);
4744 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
4745 Skip_Controlling_Formals => Skip_Controlling_Formals);
4746 end Check_Subtype_Conformant;
4748 ---------------------------
4749 -- Check_Type_Conformant --
4750 ---------------------------
4752 procedure Check_Type_Conformant
4753 (New_Id : Entity_Id;
4755 Err_Loc : Node_Id := Empty)
4758 pragma Warnings (Off, Result);
4761 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
4762 end Check_Type_Conformant;
4764 ----------------------
4765 -- Conforming_Types --
4766 ----------------------
4768 function Conforming_Types
4771 Ctype : Conformance_Type;
4772 Get_Inst : Boolean := False) return Boolean
4774 Type_1 : Entity_Id := T1;
4775 Type_2 : Entity_Id := T2;
4776 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
4778 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
4779 -- If neither T1 nor T2 are generic actual types, or if they are in
4780 -- different scopes (e.g. parent and child instances), then verify that
4781 -- the base types are equal. Otherwise T1 and T2 must be on the same
4782 -- subtype chain. The whole purpose of this procedure is to prevent
4783 -- spurious ambiguities in an instantiation that may arise if two
4784 -- distinct generic types are instantiated with the same actual.
4786 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
4787 -- An access parameter can designate an incomplete type. If the
4788 -- incomplete type is the limited view of a type from a limited_
4789 -- with_clause, check whether the non-limited view is available. If
4790 -- it is a (non-limited) incomplete type, get the full view.
4792 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
4793 -- Returns True if and only if either T1 denotes a limited view of T2
4794 -- or T2 denotes a limited view of T1. This can arise when the limited
4795 -- with view of a type is used in a subprogram declaration and the
4796 -- subprogram body is in the scope of a regular with clause for the
4797 -- same unit. In such a case, the two type entities can be considered
4798 -- identical for purposes of conformance checking.
4800 ----------------------
4801 -- Base_Types_Match --
4802 ----------------------
4804 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
4809 elsif Base_Type (T1) = Base_Type (T2) then
4811 -- The following is too permissive. A more precise test should
4812 -- check that the generic actual is an ancestor subtype of the
4815 return not Is_Generic_Actual_Type (T1)
4816 or else not Is_Generic_Actual_Type (T2)
4817 or else Scope (T1) /= Scope (T2);
4822 end Base_Types_Match;
4824 --------------------------
4825 -- Find_Designated_Type --
4826 --------------------------
4828 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
4832 Desig := Directly_Designated_Type (T);
4834 if Ekind (Desig) = E_Incomplete_Type then
4836 -- If regular incomplete type, get full view if available
4838 if Present (Full_View (Desig)) then
4839 Desig := Full_View (Desig);
4841 -- If limited view of a type, get non-limited view if available,
4842 -- and check again for a regular incomplete type.
4844 elsif Present (Non_Limited_View (Desig)) then
4845 Desig := Get_Full_View (Non_Limited_View (Desig));
4850 end Find_Designated_Type;
4852 -------------------------------
4853 -- Matches_Limited_With_View --
4854 -------------------------------
4856 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
4858 -- In some cases a type imported through a limited_with clause, and
4859 -- its nonlimited view are both visible, for example in an anonymous
4860 -- access-to-class-wide type in a formal. Both entities designate the
4863 if From_With_Type (T1)
4864 and then T2 = Available_View (T1)
4868 elsif From_With_Type (T2)
4869 and then T1 = Available_View (T2)
4876 end Matches_Limited_With_View;
4878 -- Start of processing for Conforming_Types
4881 -- The context is an instance association for a formal
4882 -- access-to-subprogram type; the formal parameter types require
4883 -- mapping because they may denote other formal parameters of the
4887 Type_1 := Get_Instance_Of (T1);
4888 Type_2 := Get_Instance_Of (T2);
4891 -- If one of the types is a view of the other introduced by a limited
4892 -- with clause, treat these as conforming for all purposes.
4894 if Matches_Limited_With_View (T1, T2) then
4897 elsif Base_Types_Match (Type_1, Type_2) then
4898 return Ctype <= Mode_Conformant
4899 or else Subtypes_Statically_Match (Type_1, Type_2);
4901 elsif Is_Incomplete_Or_Private_Type (Type_1)
4902 and then Present (Full_View (Type_1))
4903 and then Base_Types_Match (Full_View (Type_1), Type_2)
4905 return Ctype <= Mode_Conformant
4906 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
4908 elsif Ekind (Type_2) = E_Incomplete_Type
4909 and then Present (Full_View (Type_2))
4910 and then Base_Types_Match (Type_1, Full_View (Type_2))
4912 return Ctype <= Mode_Conformant
4913 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4915 elsif Is_Private_Type (Type_2)
4916 and then In_Instance
4917 and then Present (Full_View (Type_2))
4918 and then Base_Types_Match (Type_1, Full_View (Type_2))
4920 return Ctype <= Mode_Conformant
4921 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4924 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
4925 -- treated recursively because they carry a signature.
4927 Are_Anonymous_Access_To_Subprogram_Types :=
4928 Ekind (Type_1) = Ekind (Type_2)
4930 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
4932 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
4934 -- Test anonymous access type case. For this case, static subtype
4935 -- matching is required for mode conformance (RM 6.3.1(15)). We check
4936 -- the base types because we may have built internal subtype entities
4937 -- to handle null-excluding types (see Process_Formals).
4939 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
4941 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
4942 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
4945 Desig_1 : Entity_Id;
4946 Desig_2 : Entity_Id;
4949 -- In Ada2005, access constant indicators must match for
4950 -- subtype conformance.
4952 if Ada_Version >= Ada_05
4953 and then Ctype >= Subtype_Conformant
4955 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
4960 Desig_1 := Find_Designated_Type (Type_1);
4962 Desig_2 := Find_Designated_Type (Type_2);
4964 -- If the context is an instance association for a formal
4965 -- access-to-subprogram type; formal access parameter designated
4966 -- types require mapping because they may denote other formal
4967 -- parameters of the generic unit.
4970 Desig_1 := Get_Instance_Of (Desig_1);
4971 Desig_2 := Get_Instance_Of (Desig_2);
4974 -- It is possible for a Class_Wide_Type to be introduced for an
4975 -- incomplete type, in which case there is a separate class_ wide
4976 -- type for the full view. The types conform if their Etypes
4977 -- conform, i.e. one may be the full view of the other. This can
4978 -- only happen in the context of an access parameter, other uses
4979 -- of an incomplete Class_Wide_Type are illegal.
4981 if Is_Class_Wide_Type (Desig_1)
4982 and then Is_Class_Wide_Type (Desig_2)
4986 (Etype (Base_Type (Desig_1)),
4987 Etype (Base_Type (Desig_2)), Ctype);
4989 elsif Are_Anonymous_Access_To_Subprogram_Types then
4990 if Ada_Version < Ada_05 then
4991 return Ctype = Type_Conformant
4993 Subtypes_Statically_Match (Desig_1, Desig_2);
4995 -- We must check the conformance of the signatures themselves
4999 Conformant : Boolean;
5002 (Desig_1, Desig_2, Ctype, False, Conformant);
5008 return Base_Type (Desig_1) = Base_Type (Desig_2)
5009 and then (Ctype = Type_Conformant
5011 Subtypes_Statically_Match (Desig_1, Desig_2));
5015 -- Otherwise definitely no match
5018 if ((Ekind (Type_1) = E_Anonymous_Access_Type
5019 and then Is_Access_Type (Type_2))
5020 or else (Ekind (Type_2) = E_Anonymous_Access_Type
5021 and then Is_Access_Type (Type_1)))
5024 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
5026 May_Hide_Profile := True;
5031 end Conforming_Types;
5033 --------------------------
5034 -- Create_Extra_Formals --
5035 --------------------------
5037 procedure Create_Extra_Formals (E : Entity_Id) is
5039 First_Extra : Entity_Id := Empty;
5040 Last_Extra : Entity_Id;
5041 Formal_Type : Entity_Id;
5042 P_Formal : Entity_Id := Empty;
5044 function Add_Extra_Formal
5045 (Assoc_Entity : Entity_Id;
5048 Suffix : String) return Entity_Id;
5049 -- Add an extra formal to the current list of formals and extra formals.
5050 -- The extra formal is added to the end of the list of extra formals,
5051 -- and also returned as the result. These formals are always of mode IN.
5052 -- The new formal has the type Typ, is declared in Scope, and its name
5053 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
5055 ----------------------
5056 -- Add_Extra_Formal --
5057 ----------------------
5059 function Add_Extra_Formal
5060 (Assoc_Entity : Entity_Id;
5063 Suffix : String) return Entity_Id
5065 EF : constant Entity_Id :=
5066 Make_Defining_Identifier (Sloc (Assoc_Entity),
5067 Chars => New_External_Name (Chars (Assoc_Entity),
5071 -- A little optimization. Never generate an extra formal for the
5072 -- _init operand of an initialization procedure, since it could
5075 if Chars (Formal) = Name_uInit then
5079 Set_Ekind (EF, E_In_Parameter);
5080 Set_Actual_Subtype (EF, Typ);
5081 Set_Etype (EF, Typ);
5082 Set_Scope (EF, Scope);
5083 Set_Mechanism (EF, Default_Mechanism);
5084 Set_Formal_Validity (EF);
5086 if No (First_Extra) then
5088 Set_Extra_Formals (Scope, First_Extra);
5091 if Present (Last_Extra) then
5092 Set_Extra_Formal (Last_Extra, EF);
5098 end Add_Extra_Formal;
5100 -- Start of processing for Create_Extra_Formals
5103 -- We never generate extra formals if expansion is not active
5104 -- because we don't need them unless we are generating code.
5106 if not Expander_Active then
5110 -- If this is a derived subprogram then the subtypes of the parent
5111 -- subprogram's formal parameters will be used to determine the need
5112 -- for extra formals.
5114 if Is_Overloadable (E) and then Present (Alias (E)) then
5115 P_Formal := First_Formal (Alias (E));
5118 Last_Extra := Empty;
5119 Formal := First_Formal (E);
5120 while Present (Formal) loop
5121 Last_Extra := Formal;
5122 Next_Formal (Formal);
5125 -- If Extra_formals were already created, don't do it again. This
5126 -- situation may arise for subprogram types created as part of
5127 -- dispatching calls (see Expand_Dispatching_Call)
5129 if Present (Last_Extra) and then
5130 Present (Extra_Formal (Last_Extra))
5135 -- If the subprogram is a predefined dispatching subprogram then don't
5136 -- generate any extra constrained or accessibility level formals. In
5137 -- general we suppress these for internal subprograms (by not calling
5138 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
5139 -- generated stream attributes do get passed through because extra
5140 -- build-in-place formals are needed in some cases (limited 'Input).
5142 if Is_Predefined_Dispatching_Operation (E) then
5143 goto Test_For_BIP_Extras;
5146 Formal := First_Formal (E);
5147 while Present (Formal) loop
5149 -- Create extra formal for supporting the attribute 'Constrained.
5150 -- The case of a private type view without discriminants also
5151 -- requires the extra formal if the underlying type has defaulted
5154 if Ekind (Formal) /= E_In_Parameter then
5155 if Present (P_Formal) then
5156 Formal_Type := Etype (P_Formal);
5158 Formal_Type := Etype (Formal);
5161 -- Do not produce extra formals for Unchecked_Union parameters.
5162 -- Jump directly to the end of the loop.
5164 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
5165 goto Skip_Extra_Formal_Generation;
5168 if not Has_Discriminants (Formal_Type)
5169 and then Ekind (Formal_Type) in Private_Kind
5170 and then Present (Underlying_Type (Formal_Type))
5172 Formal_Type := Underlying_Type (Formal_Type);
5175 if Has_Discriminants (Formal_Type)
5176 and then not Is_Constrained (Formal_Type)
5177 and then not Is_Indefinite_Subtype (Formal_Type)
5179 Set_Extra_Constrained
5180 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "F"));
5184 -- Create extra formal for supporting accessibility checking. This
5185 -- is done for both anonymous access formals and formals of named
5186 -- access types that are marked as controlling formals. The latter
5187 -- case can occur when Expand_Dispatching_Call creates a subprogram
5188 -- type and substitutes the types of access-to-class-wide actuals
5189 -- for the anonymous access-to-specific-type of controlling formals.
5190 -- Base_Type is applied because in cases where there is a null
5191 -- exclusion the formal may have an access subtype.
5193 -- This is suppressed if we specifically suppress accessibility
5194 -- checks at the package level for either the subprogram, or the
5195 -- package in which it resides. However, we do not suppress it
5196 -- simply if the scope has accessibility checks suppressed, since
5197 -- this could cause trouble when clients are compiled with a
5198 -- different suppression setting. The explicit checks at the
5199 -- package level are safe from this point of view.
5201 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
5202 or else (Is_Controlling_Formal (Formal)
5203 and then Is_Access_Type (Base_Type (Etype (Formal)))))
5205 (Explicit_Suppress (E, Accessibility_Check)
5207 Explicit_Suppress (Scope (E), Accessibility_Check))
5210 or else Present (Extra_Accessibility (P_Formal)))
5212 -- Temporary kludge: for now we avoid creating the extra formal
5213 -- for access parameters of protected operations because of
5214 -- problem with the case of internal protected calls. ???
5216 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
5217 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
5219 Set_Extra_Accessibility
5220 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "F"));
5224 -- This label is required when skipping extra formal generation for
5225 -- Unchecked_Union parameters.
5227 <<Skip_Extra_Formal_Generation>>
5229 if Present (P_Formal) then
5230 Next_Formal (P_Formal);
5233 Next_Formal (Formal);
5236 <<Test_For_BIP_Extras>>
5238 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
5239 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
5241 if Ada_Version >= Ada_05 and then Is_Build_In_Place_Function (E) then
5243 Result_Subt : constant Entity_Id := Etype (E);
5245 Discard : Entity_Id;
5246 pragma Warnings (Off, Discard);
5249 -- In the case of functions with unconstrained result subtypes,
5250 -- add a 3-state formal indicating whether the return object is
5251 -- allocated by the caller (0), or should be allocated by the
5252 -- callee on the secondary stack (1) or in the global heap (2).
5253 -- For the moment we just use Natural for the type of this formal.
5254 -- Note that this formal isn't usually needed in the case where
5255 -- the result subtype is constrained, but it is needed when the
5256 -- function has a tagged result, because generally such functions
5257 -- can be called in a dispatching context and such calls must be
5258 -- handled like calls to a class-wide function.
5260 if not Is_Constrained (Underlying_Type (Result_Subt))
5261 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
5265 (E, Standard_Natural,
5266 E, BIP_Formal_Suffix (BIP_Alloc_Form));
5269 -- In the case of functions whose result type has controlled
5270 -- parts, we have an extra formal of type
5271 -- System.Finalization_Implementation.Finalizable_Ptr_Ptr. That
5272 -- is, we are passing a pointer to a finalization list (which is
5273 -- itself a pointer). This extra formal is then passed along to
5274 -- Move_Final_List in case of successful completion of a return
5275 -- statement. We cannot pass an 'in out' parameter, because we
5276 -- need to update the finalization list during an abort-deferred
5277 -- region, rather than using copy-back after the function
5278 -- returns. This is true even if we are able to get away with
5279 -- having 'in out' parameters, which are normally illegal for
5280 -- functions. This formal is also needed when the function has
5283 if Needs_BIP_Final_List (E) then
5286 (E, RTE (RE_Finalizable_Ptr_Ptr),
5287 E, BIP_Formal_Suffix (BIP_Final_List));
5290 -- If the result type contains tasks, we have two extra formals:
5291 -- the master of the tasks to be created, and the caller's
5292 -- activation chain.
5294 if Has_Task (Result_Subt) then
5297 (E, RTE (RE_Master_Id),
5298 E, BIP_Formal_Suffix (BIP_Master));
5301 (E, RTE (RE_Activation_Chain_Access),
5302 E, BIP_Formal_Suffix (BIP_Activation_Chain));
5305 -- All build-in-place functions get an extra formal that will be
5306 -- passed the address of the return object within the caller.
5309 Formal_Type : constant Entity_Id :=
5311 (E_Anonymous_Access_Type, E,
5312 Scope_Id => Scope (E));
5314 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
5315 Set_Etype (Formal_Type, Formal_Type);
5316 Set_Depends_On_Private
5317 (Formal_Type, Has_Private_Component (Formal_Type));
5318 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
5319 Set_Is_Access_Constant (Formal_Type, False);
5321 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
5322 -- the designated type comes from the limited view (for
5323 -- back-end purposes).
5325 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
5327 Layout_Type (Formal_Type);
5331 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
5335 end Create_Extra_Formals;
5337 -----------------------------
5338 -- Enter_Overloaded_Entity --
5339 -----------------------------
5341 procedure Enter_Overloaded_Entity (S : Entity_Id) is
5342 E : Entity_Id := Current_Entity_In_Scope (S);
5343 C_E : Entity_Id := Current_Entity (S);
5347 Set_Has_Homonym (E);
5348 Set_Has_Homonym (S);
5351 Set_Is_Immediately_Visible (S);
5352 Set_Scope (S, Current_Scope);
5354 -- Chain new entity if front of homonym in current scope, so that
5355 -- homonyms are contiguous.
5360 while Homonym (C_E) /= E loop
5361 C_E := Homonym (C_E);
5364 Set_Homonym (C_E, S);
5368 Set_Current_Entity (S);
5373 Append_Entity (S, Current_Scope);
5374 Set_Public_Status (S);
5376 if Debug_Flag_E then
5377 Write_Str ("New overloaded entity chain: ");
5378 Write_Name (Chars (S));
5381 while Present (E) loop
5382 Write_Str (" "); Write_Int (Int (E));
5389 -- Generate warning for hiding
5392 and then Comes_From_Source (S)
5393 and then In_Extended_Main_Source_Unit (S)
5400 -- Warn unless genuine overloading
5402 if (not Is_Overloadable (E) or else Subtype_Conformant (E, S))
5403 and then (Is_Immediately_Visible (E)
5405 Is_Potentially_Use_Visible (S))
5407 Error_Msg_Sloc := Sloc (E);
5408 Error_Msg_N ("declaration of & hides one#?", S);
5412 end Enter_Overloaded_Entity;
5414 -----------------------------
5415 -- Find_Corresponding_Spec --
5416 -----------------------------
5418 function Find_Corresponding_Spec
5420 Post_Error : Boolean := True) return Entity_Id
5422 Spec : constant Node_Id := Specification (N);
5423 Designator : constant Entity_Id := Defining_Entity (Spec);
5428 E := Current_Entity (Designator);
5429 while Present (E) loop
5431 -- We are looking for a matching spec. It must have the same scope,
5432 -- and the same name, and either be type conformant, or be the case
5433 -- of a library procedure spec and its body (which belong to one
5434 -- another regardless of whether they are type conformant or not).
5436 if Scope (E) = Current_Scope then
5437 if Current_Scope = Standard_Standard
5438 or else (Ekind (E) = Ekind (Designator)
5439 and then Type_Conformant (E, Designator))
5441 -- Within an instantiation, we know that spec and body are
5442 -- subtype conformant, because they were subtype conformant
5443 -- in the generic. We choose the subtype-conformant entity
5444 -- here as well, to resolve spurious ambiguities in the
5445 -- instance that were not present in the generic (i.e. when
5446 -- two different types are given the same actual). If we are
5447 -- looking for a spec to match a body, full conformance is
5451 Set_Convention (Designator, Convention (E));
5453 if Nkind (N) = N_Subprogram_Body
5454 and then Present (Homonym (E))
5455 and then not Fully_Conformant (E, Designator)
5459 elsif not Subtype_Conformant (E, Designator) then
5464 if not Has_Completion (E) then
5465 if Nkind (N) /= N_Subprogram_Body_Stub then
5466 Set_Corresponding_Spec (N, E);
5469 Set_Has_Completion (E);
5472 elsif Nkind (Parent (N)) = N_Subunit then
5474 -- If this is the proper body of a subunit, the completion
5475 -- flag is set when analyzing the stub.
5479 -- If E is an internal function with a controlling result
5480 -- that was created for an operation inherited by a null
5481 -- extension, it may be overridden by a body without a previous
5482 -- spec (one more reason why these should be shunned). In that
5483 -- case remove the generated body, because the current one is
5484 -- the explicit overriding.
5486 elsif Ekind (E) = E_Function
5487 and then Ada_Version >= Ada_05
5488 and then not Comes_From_Source (E)
5489 and then Has_Controlling_Result (E)
5490 and then Is_Null_Extension (Etype (E))
5491 and then Comes_From_Source (Spec)
5493 Set_Has_Completion (E, False);
5495 if Expander_Active then
5497 (Unit_Declaration_Node
5498 (Corresponding_Body (Unit_Declaration_Node (E))));
5501 -- If expansion is disabled, the wrapper function has not
5502 -- been generated, and this is the standard case of a late
5503 -- body overriding an inherited operation.
5509 -- If the body already exists, then this is an error unless
5510 -- the previous declaration is the implicit declaration of a
5511 -- derived subprogram, or this is a spurious overloading in an
5514 elsif No (Alias (E))
5515 and then not Is_Intrinsic_Subprogram (E)
5516 and then not In_Instance
5519 Error_Msg_Sloc := Sloc (E);
5520 if Is_Imported (E) then
5522 ("body not allowed for imported subprogram & declared#",
5525 Error_Msg_NE ("duplicate body for & declared#", N, E);
5529 -- Child units cannot be overloaded, so a conformance mismatch
5530 -- between body and a previous spec is an error.
5532 elsif Is_Child_Unit (E)
5534 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
5536 Nkind (Parent (Unit_Declaration_Node (Designator))) =
5541 ("body of child unit does not match previous declaration", N);
5549 -- On exit, we know that no previous declaration of subprogram exists
5552 end Find_Corresponding_Spec;
5554 ----------------------
5555 -- Fully_Conformant --
5556 ----------------------
5558 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5561 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
5563 end Fully_Conformant;
5565 ----------------------------------
5566 -- Fully_Conformant_Expressions --
5567 ----------------------------------
5569 function Fully_Conformant_Expressions
5570 (Given_E1 : Node_Id;
5571 Given_E2 : Node_Id) return Boolean
5573 E1 : constant Node_Id := Original_Node (Given_E1);
5574 E2 : constant Node_Id := Original_Node (Given_E2);
5575 -- We always test conformance on original nodes, since it is possible
5576 -- for analysis and/or expansion to make things look as though they
5577 -- conform when they do not, e.g. by converting 1+2 into 3.
5579 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
5580 renames Fully_Conformant_Expressions;
5582 function FCL (L1, L2 : List_Id) return Boolean;
5583 -- Compare elements of two lists for conformance. Elements have to
5584 -- be conformant, and actuals inserted as default parameters do not
5585 -- match explicit actuals with the same value.
5587 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
5588 -- Compare an operator node with a function call
5594 function FCL (L1, L2 : List_Id) return Boolean is
5598 if L1 = No_List then
5604 if L2 = No_List then
5610 -- Compare two lists, skipping rewrite insertions (we want to
5611 -- compare the original trees, not the expanded versions!)
5614 if Is_Rewrite_Insertion (N1) then
5616 elsif Is_Rewrite_Insertion (N2) then
5622 elsif not FCE (N1, N2) then
5635 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
5636 Actuals : constant List_Id := Parameter_Associations (Call_Node);
5641 or else Entity (Op_Node) /= Entity (Name (Call_Node))
5646 Act := First (Actuals);
5648 if Nkind (Op_Node) in N_Binary_Op then
5650 if not FCE (Left_Opnd (Op_Node), Act) then
5657 return Present (Act)
5658 and then FCE (Right_Opnd (Op_Node), Act)
5659 and then No (Next (Act));
5663 -- Start of processing for Fully_Conformant_Expressions
5666 -- Non-conformant if paren count does not match. Note: if some idiot
5667 -- complains that we don't do this right for more than 3 levels of
5668 -- parentheses, they will be treated with the respect they deserve!
5670 if Paren_Count (E1) /= Paren_Count (E2) then
5673 -- If same entities are referenced, then they are conformant even if
5674 -- they have different forms (RM 8.3.1(19-20)).
5676 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
5677 if Present (Entity (E1)) then
5678 return Entity (E1) = Entity (E2)
5679 or else (Chars (Entity (E1)) = Chars (Entity (E2))
5680 and then Ekind (Entity (E1)) = E_Discriminant
5681 and then Ekind (Entity (E2)) = E_In_Parameter);
5683 elsif Nkind (E1) = N_Expanded_Name
5684 and then Nkind (E2) = N_Expanded_Name
5685 and then Nkind (Selector_Name (E1)) = N_Character_Literal
5686 and then Nkind (Selector_Name (E2)) = N_Character_Literal
5688 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
5691 -- Identifiers in component associations don't always have
5692 -- entities, but their names must conform.
5694 return Nkind (E1) = N_Identifier
5695 and then Nkind (E2) = N_Identifier
5696 and then Chars (E1) = Chars (E2);
5699 elsif Nkind (E1) = N_Character_Literal
5700 and then Nkind (E2) = N_Expanded_Name
5702 return Nkind (Selector_Name (E2)) = N_Character_Literal
5703 and then Chars (E1) = Chars (Selector_Name (E2));
5705 elsif Nkind (E2) = N_Character_Literal
5706 and then Nkind (E1) = N_Expanded_Name
5708 return Nkind (Selector_Name (E1)) = N_Character_Literal
5709 and then Chars (E2) = Chars (Selector_Name (E1));
5711 elsif Nkind (E1) in N_Op
5712 and then Nkind (E2) = N_Function_Call
5714 return FCO (E1, E2);
5716 elsif Nkind (E2) in N_Op
5717 and then Nkind (E1) = N_Function_Call
5719 return FCO (E2, E1);
5721 -- Otherwise we must have the same syntactic entity
5723 elsif Nkind (E1) /= Nkind (E2) then
5726 -- At this point, we specialize by node type
5733 FCL (Expressions (E1), Expressions (E2))
5734 and then FCL (Component_Associations (E1),
5735 Component_Associations (E2));
5738 if Nkind (Expression (E1)) = N_Qualified_Expression
5740 Nkind (Expression (E2)) = N_Qualified_Expression
5742 return FCE (Expression (E1), Expression (E2));
5744 -- Check that the subtype marks and any constraints
5749 Indic1 : constant Node_Id := Expression (E1);
5750 Indic2 : constant Node_Id := Expression (E2);
5755 if Nkind (Indic1) /= N_Subtype_Indication then
5757 Nkind (Indic2) /= N_Subtype_Indication
5758 and then Entity (Indic1) = Entity (Indic2);
5760 elsif Nkind (Indic2) /= N_Subtype_Indication then
5762 Nkind (Indic1) /= N_Subtype_Indication
5763 and then Entity (Indic1) = Entity (Indic2);
5766 if Entity (Subtype_Mark (Indic1)) /=
5767 Entity (Subtype_Mark (Indic2))
5772 Elt1 := First (Constraints (Constraint (Indic1)));
5773 Elt2 := First (Constraints (Constraint (Indic2)));
5775 while Present (Elt1) and then Present (Elt2) loop
5776 if not FCE (Elt1, Elt2) then
5789 when N_Attribute_Reference =>
5791 Attribute_Name (E1) = Attribute_Name (E2)
5792 and then FCL (Expressions (E1), Expressions (E2));
5796 Entity (E1) = Entity (E2)
5797 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
5798 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5800 when N_And_Then | N_Or_Else | N_Membership_Test =>
5802 FCE (Left_Opnd (E1), Left_Opnd (E2))
5804 FCE (Right_Opnd (E1), Right_Opnd (E2));
5806 when N_Character_Literal =>
5808 Char_Literal_Value (E1) = Char_Literal_Value (E2);
5810 when N_Component_Association =>
5812 FCL (Choices (E1), Choices (E2))
5813 and then FCE (Expression (E1), Expression (E2));
5815 when N_Conditional_Expression =>
5817 FCL (Expressions (E1), Expressions (E2));
5819 when N_Explicit_Dereference =>
5821 FCE (Prefix (E1), Prefix (E2));
5823 when N_Extension_Aggregate =>
5825 FCL (Expressions (E1), Expressions (E2))
5826 and then Null_Record_Present (E1) =
5827 Null_Record_Present (E2)
5828 and then FCL (Component_Associations (E1),
5829 Component_Associations (E2));
5831 when N_Function_Call =>
5833 FCE (Name (E1), Name (E2))
5834 and then FCL (Parameter_Associations (E1),
5835 Parameter_Associations (E2));
5837 when N_Indexed_Component =>
5839 FCE (Prefix (E1), Prefix (E2))
5840 and then FCL (Expressions (E1), Expressions (E2));
5842 when N_Integer_Literal =>
5843 return (Intval (E1) = Intval (E2));
5848 when N_Operator_Symbol =>
5850 Chars (E1) = Chars (E2);
5852 when N_Others_Choice =>
5855 when N_Parameter_Association =>
5857 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
5858 and then FCE (Explicit_Actual_Parameter (E1),
5859 Explicit_Actual_Parameter (E2));
5861 when N_Qualified_Expression =>
5863 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5864 and then FCE (Expression (E1), Expression (E2));
5868 FCE (Low_Bound (E1), Low_Bound (E2))
5869 and then FCE (High_Bound (E1), High_Bound (E2));
5871 when N_Real_Literal =>
5872 return (Realval (E1) = Realval (E2));
5874 when N_Selected_Component =>
5876 FCE (Prefix (E1), Prefix (E2))
5877 and then FCE (Selector_Name (E1), Selector_Name (E2));
5881 FCE (Prefix (E1), Prefix (E2))
5882 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
5884 when N_String_Literal =>
5886 S1 : constant String_Id := Strval (E1);
5887 S2 : constant String_Id := Strval (E2);
5888 L1 : constant Nat := String_Length (S1);
5889 L2 : constant Nat := String_Length (S2);
5896 for J in 1 .. L1 loop
5897 if Get_String_Char (S1, J) /=
5898 Get_String_Char (S2, J)
5908 when N_Type_Conversion =>
5910 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5911 and then FCE (Expression (E1), Expression (E2));
5915 Entity (E1) = Entity (E2)
5916 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5918 when N_Unchecked_Type_Conversion =>
5920 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5921 and then FCE (Expression (E1), Expression (E2));
5923 -- All other node types cannot appear in this context. Strictly
5924 -- we should raise a fatal internal error. Instead we just ignore
5925 -- the nodes. This means that if anyone makes a mistake in the
5926 -- expander and mucks an expression tree irretrievably, the
5927 -- result will be a failure to detect a (probably very obscure)
5928 -- case of non-conformance, which is better than bombing on some
5929 -- case where two expressions do in fact conform.
5936 end Fully_Conformant_Expressions;
5938 ----------------------------------------
5939 -- Fully_Conformant_Discrete_Subtypes --
5940 ----------------------------------------
5942 function Fully_Conformant_Discrete_Subtypes
5943 (Given_S1 : Node_Id;
5944 Given_S2 : Node_Id) return Boolean
5946 S1 : constant Node_Id := Original_Node (Given_S1);
5947 S2 : constant Node_Id := Original_Node (Given_S2);
5949 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
5950 -- Special-case for a bound given by a discriminant, which in the body
5951 -- is replaced with the discriminal of the enclosing type.
5953 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
5954 -- Check both bounds
5956 -----------------------
5957 -- Conforming_Bounds --
5958 -----------------------
5960 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
5962 if Is_Entity_Name (B1)
5963 and then Is_Entity_Name (B2)
5964 and then Ekind (Entity (B1)) = E_Discriminant
5966 return Chars (B1) = Chars (B2);
5969 return Fully_Conformant_Expressions (B1, B2);
5971 end Conforming_Bounds;
5973 -----------------------
5974 -- Conforming_Ranges --
5975 -----------------------
5977 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
5980 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
5982 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
5983 end Conforming_Ranges;
5985 -- Start of processing for Fully_Conformant_Discrete_Subtypes
5988 if Nkind (S1) /= Nkind (S2) then
5991 elsif Is_Entity_Name (S1) then
5992 return Entity (S1) = Entity (S2);
5994 elsif Nkind (S1) = N_Range then
5995 return Conforming_Ranges (S1, S2);
5997 elsif Nkind (S1) = N_Subtype_Indication then
5999 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
6002 (Range_Expression (Constraint (S1)),
6003 Range_Expression (Constraint (S2)));
6007 end Fully_Conformant_Discrete_Subtypes;
6009 --------------------
6010 -- Install_Entity --
6011 --------------------
6013 procedure Install_Entity (E : Entity_Id) is
6014 Prev : constant Entity_Id := Current_Entity (E);
6016 Set_Is_Immediately_Visible (E);
6017 Set_Current_Entity (E);
6018 Set_Homonym (E, Prev);
6021 ---------------------
6022 -- Install_Formals --
6023 ---------------------
6025 procedure Install_Formals (Id : Entity_Id) is
6028 F := First_Formal (Id);
6029 while Present (F) loop
6033 end Install_Formals;
6035 -----------------------------
6036 -- Is_Interface_Conformant --
6037 -----------------------------
6039 function Is_Interface_Conformant
6040 (Tagged_Type : Entity_Id;
6041 Iface_Prim : Entity_Id;
6042 Prim : Entity_Id) return Boolean
6044 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
6045 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
6048 pragma Assert (Is_Subprogram (Iface_Prim)
6049 and then Is_Subprogram (Prim)
6050 and then Is_Dispatching_Operation (Iface_Prim)
6051 and then Is_Dispatching_Operation (Prim));
6053 pragma Assert (Is_Interface (Iface)
6054 or else (Present (Alias (Iface_Prim))
6057 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
6059 if Prim = Iface_Prim
6060 or else not Is_Subprogram (Prim)
6061 or else Ekind (Prim) /= Ekind (Iface_Prim)
6062 or else not Is_Dispatching_Operation (Prim)
6063 or else Scope (Prim) /= Scope (Tagged_Type)
6065 or else Base_Type (Typ) /= Tagged_Type
6066 or else not Primitive_Names_Match (Iface_Prim, Prim)
6070 -- Case of a procedure, or a function that does not have a controlling
6071 -- result (I or access I).
6073 elsif Ekind (Iface_Prim) = E_Procedure
6074 or else Etype (Prim) = Etype (Iface_Prim)
6075 or else not Has_Controlling_Result (Prim)
6077 return Type_Conformant (Prim, Iface_Prim,
6078 Skip_Controlling_Formals => True);
6080 -- Case of a function returning an interface, or an access to one.
6081 -- Check that the return types correspond.
6083 elsif Implements_Interface (Typ, Iface) then
6084 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
6086 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
6091 Type_Conformant (Prim, Iface_Prim,
6092 Skip_Controlling_Formals => True);
6098 end Is_Interface_Conformant;
6100 ---------------------------------
6101 -- Is_Non_Overriding_Operation --
6102 ---------------------------------
6104 function Is_Non_Overriding_Operation
6105 (Prev_E : Entity_Id;
6106 New_E : Entity_Id) return Boolean
6110 G_Typ : Entity_Id := Empty;
6112 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
6113 -- If F_Type is a derived type associated with a generic actual subtype,
6114 -- then return its Generic_Parent_Type attribute, else return Empty.
6116 function Types_Correspond
6117 (P_Type : Entity_Id;
6118 N_Type : Entity_Id) return Boolean;
6119 -- Returns true if and only if the types (or designated types in the
6120 -- case of anonymous access types) are the same or N_Type is derived
6121 -- directly or indirectly from P_Type.
6123 -----------------------------
6124 -- Get_Generic_Parent_Type --
6125 -----------------------------
6127 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
6132 if Is_Derived_Type (F_Typ)
6133 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
6135 -- The tree must be traversed to determine the parent subtype in
6136 -- the generic unit, which unfortunately isn't always available
6137 -- via semantic attributes. ??? (Note: The use of Original_Node
6138 -- is needed for cases where a full derived type has been
6141 Indic := Subtype_Indication
6142 (Type_Definition (Original_Node (Parent (F_Typ))));
6144 if Nkind (Indic) = N_Subtype_Indication then
6145 G_Typ := Entity (Subtype_Mark (Indic));
6147 G_Typ := Entity (Indic);
6150 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
6151 and then Present (Generic_Parent_Type (Parent (G_Typ)))
6153 return Generic_Parent_Type (Parent (G_Typ));
6158 end Get_Generic_Parent_Type;
6160 ----------------------
6161 -- Types_Correspond --
6162 ----------------------
6164 function Types_Correspond
6165 (P_Type : Entity_Id;
6166 N_Type : Entity_Id) return Boolean
6168 Prev_Type : Entity_Id := Base_Type (P_Type);
6169 New_Type : Entity_Id := Base_Type (N_Type);
6172 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
6173 Prev_Type := Designated_Type (Prev_Type);
6176 if Ekind (New_Type) = E_Anonymous_Access_Type then
6177 New_Type := Designated_Type (New_Type);
6180 if Prev_Type = New_Type then
6183 elsif not Is_Class_Wide_Type (New_Type) then
6184 while Etype (New_Type) /= New_Type loop
6185 New_Type := Etype (New_Type);
6186 if New_Type = Prev_Type then
6192 end Types_Correspond;
6194 -- Start of processing for Is_Non_Overriding_Operation
6197 -- In the case where both operations are implicit derived subprograms
6198 -- then neither overrides the other. This can only occur in certain
6199 -- obscure cases (e.g., derivation from homographs created in a generic
6202 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
6205 elsif Ekind (Current_Scope) = E_Package
6206 and then Is_Generic_Instance (Current_Scope)
6207 and then In_Private_Part (Current_Scope)
6208 and then Comes_From_Source (New_E)
6210 -- We examine the formals and result subtype of the inherited
6211 -- operation, to determine whether their type is derived from (the
6212 -- instance of) a generic type.
6214 Formal := First_Formal (Prev_E);
6216 while Present (Formal) loop
6217 F_Typ := Base_Type (Etype (Formal));
6219 if Ekind (F_Typ) = E_Anonymous_Access_Type then
6220 F_Typ := Designated_Type (F_Typ);
6223 G_Typ := Get_Generic_Parent_Type (F_Typ);
6225 Next_Formal (Formal);
6228 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
6229 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
6236 -- If the generic type is a private type, then the original
6237 -- operation was not overriding in the generic, because there was
6238 -- no primitive operation to override.
6240 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
6241 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
6242 N_Formal_Private_Type_Definition
6246 -- The generic parent type is the ancestor of a formal derived
6247 -- type declaration. We need to check whether it has a primitive
6248 -- operation that should be overridden by New_E in the generic.
6252 P_Formal : Entity_Id;
6253 N_Formal : Entity_Id;
6257 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
6260 while Present (Prim_Elt) loop
6261 P_Prim := Node (Prim_Elt);
6263 if Chars (P_Prim) = Chars (New_E)
6264 and then Ekind (P_Prim) = Ekind (New_E)
6266 P_Formal := First_Formal (P_Prim);
6267 N_Formal := First_Formal (New_E);
6268 while Present (P_Formal) and then Present (N_Formal) loop
6269 P_Typ := Etype (P_Formal);
6270 N_Typ := Etype (N_Formal);
6272 if not Types_Correspond (P_Typ, N_Typ) then
6276 Next_Entity (P_Formal);
6277 Next_Entity (N_Formal);
6280 -- Found a matching primitive operation belonging to the
6281 -- formal ancestor type, so the new subprogram is
6285 and then No (N_Formal)
6286 and then (Ekind (New_E) /= E_Function
6289 (Etype (P_Prim), Etype (New_E)))
6295 Next_Elmt (Prim_Elt);
6298 -- If no match found, then the new subprogram does not
6299 -- override in the generic (nor in the instance).
6307 end Is_Non_Overriding_Operation;
6309 ------------------------------
6310 -- Make_Inequality_Operator --
6311 ------------------------------
6313 -- S is the defining identifier of an equality operator. We build a
6314 -- subprogram declaration with the right signature. This operation is
6315 -- intrinsic, because it is always expanded as the negation of the
6316 -- call to the equality function.
6318 procedure Make_Inequality_Operator (S : Entity_Id) is
6319 Loc : constant Source_Ptr := Sloc (S);
6322 Op_Name : Entity_Id;
6324 FF : constant Entity_Id := First_Formal (S);
6325 NF : constant Entity_Id := Next_Formal (FF);
6328 -- Check that equality was properly defined, ignore call if not
6335 A : constant Entity_Id :=
6336 Make_Defining_Identifier (Sloc (FF),
6337 Chars => Chars (FF));
6339 B : constant Entity_Id :=
6340 Make_Defining_Identifier (Sloc (NF),
6341 Chars => Chars (NF));
6344 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
6346 Formals := New_List (
6347 Make_Parameter_Specification (Loc,
6348 Defining_Identifier => A,
6350 New_Reference_To (Etype (First_Formal (S)),
6351 Sloc (Etype (First_Formal (S))))),
6353 Make_Parameter_Specification (Loc,
6354 Defining_Identifier => B,
6356 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
6357 Sloc (Etype (Next_Formal (First_Formal (S)))))));
6360 Make_Subprogram_Declaration (Loc,
6362 Make_Function_Specification (Loc,
6363 Defining_Unit_Name => Op_Name,
6364 Parameter_Specifications => Formals,
6365 Result_Definition =>
6366 New_Reference_To (Standard_Boolean, Loc)));
6368 -- Insert inequality right after equality if it is explicit or after
6369 -- the derived type when implicit. These entities are created only
6370 -- for visibility purposes, and eventually replaced in the course of
6371 -- expansion, so they do not need to be attached to the tree and seen
6372 -- by the back-end. Keeping them internal also avoids spurious
6373 -- freezing problems. The declaration is inserted in the tree for
6374 -- analysis, and removed afterwards. If the equality operator comes
6375 -- from an explicit declaration, attach the inequality immediately
6376 -- after. Else the equality is inherited from a derived type
6377 -- declaration, so insert inequality after that declaration.
6379 if No (Alias (S)) then
6380 Insert_After (Unit_Declaration_Node (S), Decl);
6381 elsif Is_List_Member (Parent (S)) then
6382 Insert_After (Parent (S), Decl);
6384 Insert_After (Parent (Etype (First_Formal (S))), Decl);
6387 Mark_Rewrite_Insertion (Decl);
6388 Set_Is_Intrinsic_Subprogram (Op_Name);
6391 Set_Has_Completion (Op_Name);
6392 Set_Corresponding_Equality (Op_Name, S);
6393 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
6395 end Make_Inequality_Operator;
6397 ----------------------
6398 -- May_Need_Actuals --
6399 ----------------------
6401 procedure May_Need_Actuals (Fun : Entity_Id) is
6406 F := First_Formal (Fun);
6408 while Present (F) loop
6409 if No (Default_Value (F)) then
6417 Set_Needs_No_Actuals (Fun, B);
6418 end May_Need_Actuals;
6420 ---------------------
6421 -- Mode_Conformant --
6422 ---------------------
6424 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6427 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
6429 end Mode_Conformant;
6431 ---------------------------
6432 -- New_Overloaded_Entity --
6433 ---------------------------
6435 procedure New_Overloaded_Entity
6437 Derived_Type : Entity_Id := Empty)
6439 Overridden_Subp : Entity_Id := Empty;
6440 -- Set if the current scope has an operation that is type-conformant
6441 -- with S, and becomes hidden by S.
6443 Is_Primitive_Subp : Boolean;
6444 -- Set to True if the new subprogram is primitive
6447 -- Entity that S overrides
6449 Prev_Vis : Entity_Id := Empty;
6450 -- Predecessor of E in Homonym chain
6452 procedure Check_For_Primitive_Subprogram
6453 (Is_Primitive : out Boolean;
6454 Is_Overriding : Boolean := False);
6455 -- If the subprogram being analyzed is a primitive operation of the type
6456 -- of a formal or result, set the Has_Primitive_Operations flag on the
6457 -- type, and set Is_Primitive to True (otherwise set to False). Set the
6458 -- corresponding flag on the entity itself for later use.
6460 procedure Check_Synchronized_Overriding
6461 (Def_Id : Entity_Id;
6462 Overridden_Subp : out Entity_Id);
6463 -- First determine if Def_Id is an entry or a subprogram either defined
6464 -- in the scope of a task or protected type, or is a primitive of such
6465 -- a type. Check whether Def_Id overrides a subprogram of an interface
6466 -- implemented by the synchronized type, return the overridden entity
6469 function Is_Private_Declaration (E : Entity_Id) return Boolean;
6470 -- Check that E is declared in the private part of the current package,
6471 -- or in the package body, where it may hide a previous declaration.
6472 -- We can't use In_Private_Part by itself because this flag is also
6473 -- set when freezing entities, so we must examine the place of the
6474 -- declaration in the tree, and recognize wrapper packages as well.
6476 function Is_Overriding_Alias
6478 New_E : Entity_Id) return Boolean;
6479 -- Check whether new subprogram and old subprogram are both inherited
6480 -- from subprograms that have distinct dispatch table entries. This can
6481 -- occur with derivations from instances with accidental homonyms.
6482 -- The function is conservative given that the converse is only true
6483 -- within instances that contain accidental overloadings.
6485 ------------------------------------
6486 -- Check_For_Primitive_Subprogram --
6487 ------------------------------------
6489 procedure Check_For_Primitive_Subprogram
6490 (Is_Primitive : out Boolean;
6491 Is_Overriding : Boolean := False)
6497 function Visible_Part_Type (T : Entity_Id) return Boolean;
6498 -- Returns true if T is declared in the visible part of
6499 -- the current package scope; otherwise returns false.
6500 -- Assumes that T is declared in a package.
6502 procedure Check_Private_Overriding (T : Entity_Id);
6503 -- Checks that if a primitive abstract subprogram of a visible
6504 -- abstract type is declared in a private part, then it must
6505 -- override an abstract subprogram declared in the visible part.
6506 -- Also checks that if a primitive function with a controlling
6507 -- result is declared in a private part, then it must override
6508 -- a function declared in the visible part.
6510 ------------------------------
6511 -- Check_Private_Overriding --
6512 ------------------------------
6514 procedure Check_Private_Overriding (T : Entity_Id) is
6516 if Is_Package_Or_Generic_Package (Current_Scope)
6517 and then In_Private_Part (Current_Scope)
6518 and then Visible_Part_Type (T)
6519 and then not In_Instance
6521 if Is_Abstract_Type (T)
6522 and then Is_Abstract_Subprogram (S)
6523 and then (not Is_Overriding
6524 or else not Is_Abstract_Subprogram (E))
6526 Error_Msg_N ("abstract subprograms must be visible "
6527 & "(RM 3.9.3(10))!", S);
6529 elsif Ekind (S) = E_Function
6530 and then Is_Tagged_Type (T)
6531 and then T = Base_Type (Etype (S))
6532 and then not Is_Overriding
6535 ("private function with tagged result must"
6536 & " override visible-part function", S);
6538 ("\move subprogram to the visible part"
6539 & " (RM 3.9.3(10))", S);
6542 end Check_Private_Overriding;
6544 -----------------------
6545 -- Visible_Part_Type --
6546 -----------------------
6548 function Visible_Part_Type (T : Entity_Id) return Boolean is
6549 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
6553 -- If the entity is a private type, then it must be
6554 -- declared in a visible part.
6556 if Ekind (T) in Private_Kind then
6560 -- Otherwise, we traverse the visible part looking for its
6561 -- corresponding declaration. We cannot use the declaration
6562 -- node directly because in the private part the entity of a
6563 -- private type is the one in the full view, which does not
6564 -- indicate that it is the completion of something visible.
6566 N := First (Visible_Declarations (Specification (P)));
6567 while Present (N) loop
6568 if Nkind (N) = N_Full_Type_Declaration
6569 and then Present (Defining_Identifier (N))
6570 and then T = Defining_Identifier (N)
6574 elsif Nkind_In (N, N_Private_Type_Declaration,
6575 N_Private_Extension_Declaration)
6576 and then Present (Defining_Identifier (N))
6577 and then T = Full_View (Defining_Identifier (N))
6586 end Visible_Part_Type;
6588 -- Start of processing for Check_For_Primitive_Subprogram
6591 Is_Primitive := False;
6593 if not Comes_From_Source (S) then
6596 -- If subprogram is at library level, it is not primitive operation
6598 elsif Current_Scope = Standard_Standard then
6601 elsif (Is_Package_Or_Generic_Package (Current_Scope)
6602 and then not In_Package_Body (Current_Scope))
6603 or else Is_Overriding
6605 -- For function, check return type
6607 if Ekind (S) = E_Function then
6608 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
6609 F_Typ := Designated_Type (Etype (S));
6614 B_Typ := Base_Type (F_Typ);
6616 if Scope (B_Typ) = Current_Scope
6617 and then not Is_Class_Wide_Type (B_Typ)
6618 and then not Is_Generic_Type (B_Typ)
6620 Is_Primitive := True;
6621 Set_Has_Primitive_Operations (B_Typ);
6622 Set_Is_Primitive (S);
6623 Check_Private_Overriding (B_Typ);
6627 -- For all subprograms, check formals
6629 Formal := First_Formal (S);
6630 while Present (Formal) loop
6631 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
6632 F_Typ := Designated_Type (Etype (Formal));
6634 F_Typ := Etype (Formal);
6637 B_Typ := Base_Type (F_Typ);
6639 if Ekind (B_Typ) = E_Access_Subtype then
6640 B_Typ := Base_Type (B_Typ);
6643 if Scope (B_Typ) = Current_Scope
6644 and then not Is_Class_Wide_Type (B_Typ)
6645 and then not Is_Generic_Type (B_Typ)
6647 Is_Primitive := True;
6648 Set_Is_Primitive (S);
6649 Set_Has_Primitive_Operations (B_Typ);
6650 Check_Private_Overriding (B_Typ);
6653 Next_Formal (Formal);
6656 end Check_For_Primitive_Subprogram;
6658 -----------------------------------
6659 -- Check_Synchronized_Overriding --
6660 -----------------------------------
6662 procedure Check_Synchronized_Overriding
6663 (Def_Id : Entity_Id;
6664 Overridden_Subp : out Entity_Id)
6666 Ifaces_List : Elist_Id;
6670 function Matches_Prefixed_View_Profile
6671 (Prim_Params : List_Id;
6672 Iface_Params : List_Id) return Boolean;
6673 -- Determine whether a subprogram's parameter profile Prim_Params
6674 -- matches that of a potentially overridden interface subprogram
6675 -- Iface_Params. Also determine if the type of first parameter of
6676 -- Iface_Params is an implemented interface.
6678 -----------------------------------
6679 -- Matches_Prefixed_View_Profile --
6680 -----------------------------------
6682 function Matches_Prefixed_View_Profile
6683 (Prim_Params : List_Id;
6684 Iface_Params : List_Id) return Boolean
6686 Iface_Id : Entity_Id;
6687 Iface_Param : Node_Id;
6688 Iface_Typ : Entity_Id;
6689 Prim_Id : Entity_Id;
6690 Prim_Param : Node_Id;
6691 Prim_Typ : Entity_Id;
6693 function Is_Implemented
6694 (Ifaces_List : Elist_Id;
6695 Iface : Entity_Id) return Boolean;
6696 -- Determine if Iface is implemented by the current task or
6699 --------------------
6700 -- Is_Implemented --
6701 --------------------
6703 function Is_Implemented
6704 (Ifaces_List : Elist_Id;
6705 Iface : Entity_Id) return Boolean
6707 Iface_Elmt : Elmt_Id;
6710 Iface_Elmt := First_Elmt (Ifaces_List);
6711 while Present (Iface_Elmt) loop
6712 if Node (Iface_Elmt) = Iface then
6716 Next_Elmt (Iface_Elmt);
6722 -- Start of processing for Matches_Prefixed_View_Profile
6725 Iface_Param := First (Iface_Params);
6726 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
6728 if Is_Access_Type (Iface_Typ) then
6729 Iface_Typ := Designated_Type (Iface_Typ);
6732 Prim_Param := First (Prim_Params);
6734 -- The first parameter of the potentially overridden subprogram
6735 -- must be an interface implemented by Prim.
6737 if not Is_Interface (Iface_Typ)
6738 or else not Is_Implemented (Ifaces_List, Iface_Typ)
6743 -- The checks on the object parameters are done, move onto the
6744 -- rest of the parameters.
6746 if not In_Scope then
6747 Prim_Param := Next (Prim_Param);
6750 Iface_Param := Next (Iface_Param);
6751 while Present (Iface_Param) and then Present (Prim_Param) loop
6752 Iface_Id := Defining_Identifier (Iface_Param);
6753 Iface_Typ := Find_Parameter_Type (Iface_Param);
6755 Prim_Id := Defining_Identifier (Prim_Param);
6756 Prim_Typ := Find_Parameter_Type (Prim_Param);
6758 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
6759 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
6760 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
6762 Iface_Typ := Designated_Type (Iface_Typ);
6763 Prim_Typ := Designated_Type (Prim_Typ);
6766 -- Case of multiple interface types inside a parameter profile
6768 -- (Obj_Param : in out Iface; ...; Param : Iface)
6770 -- If the interface type is implemented, then the matching type
6771 -- in the primitive should be the implementing record type.
6773 if Ekind (Iface_Typ) = E_Record_Type
6774 and then Is_Interface (Iface_Typ)
6775 and then Is_Implemented (Ifaces_List, Iface_Typ)
6777 if Prim_Typ /= Typ then
6781 -- The two parameters must be both mode and subtype conformant
6783 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
6785 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
6794 -- One of the two lists contains more parameters than the other
6796 if Present (Iface_Param) or else Present (Prim_Param) then
6801 end Matches_Prefixed_View_Profile;
6803 -- Start of processing for Check_Synchronized_Overriding
6806 Overridden_Subp := Empty;
6808 -- Def_Id must be an entry or a subprogram. We should skip predefined
6809 -- primitives internally generated by the frontend; however at this
6810 -- stage predefined primitives are still not fully decorated. As a
6811 -- minor optimization we skip here internally generated subprograms.
6813 if (Ekind (Def_Id) /= E_Entry
6814 and then Ekind (Def_Id) /= E_Function
6815 and then Ekind (Def_Id) /= E_Procedure)
6816 or else not Comes_From_Source (Def_Id)
6821 -- Search for the concurrent declaration since it contains the list
6822 -- of all implemented interfaces. In this case, the subprogram is
6823 -- declared within the scope of a protected or a task type.
6825 if Present (Scope (Def_Id))
6826 and then Is_Concurrent_Type (Scope (Def_Id))
6827 and then not Is_Generic_Actual_Type (Scope (Def_Id))
6829 Typ := Scope (Def_Id);
6832 -- The enclosing scope is not a synchronized type and the subprogram
6835 elsif No (First_Formal (Def_Id)) then
6838 -- The subprogram has formals and hence it may be a primitive of a
6842 Typ := Etype (First_Formal (Def_Id));
6844 if Is_Access_Type (Typ) then
6845 Typ := Directly_Designated_Type (Typ);
6848 if Is_Concurrent_Type (Typ)
6849 and then not Is_Generic_Actual_Type (Typ)
6853 -- This case occurs when the concurrent type is declared within
6854 -- a generic unit. As a result the corresponding record has been
6855 -- built and used as the type of the first formal, we just have
6856 -- to retrieve the corresponding concurrent type.
6858 elsif Is_Concurrent_Record_Type (Typ)
6859 and then Present (Corresponding_Concurrent_Type (Typ))
6861 Typ := Corresponding_Concurrent_Type (Typ);
6869 -- There is no overriding to check if is an inherited operation in a
6870 -- type derivation on for a generic actual.
6872 Collect_Interfaces (Typ, Ifaces_List);
6874 if Is_Empty_Elmt_List (Ifaces_List) then
6878 -- Determine whether entry or subprogram Def_Id overrides a primitive
6879 -- operation that belongs to one of the interfaces in Ifaces_List.
6882 Candidate : Entity_Id := Empty;
6883 Hom : Entity_Id := Empty;
6884 Iface_Typ : Entity_Id;
6885 Subp : Entity_Id := Empty;
6888 -- Traverse the homonym chain, looking at a potentially
6889 -- overridden subprogram that belongs to an implemented
6892 Hom := Current_Entity_In_Scope (Def_Id);
6893 while Present (Hom) loop
6897 or else not Is_Overloadable (Subp)
6898 or else not Is_Primitive (Subp)
6899 or else not Is_Dispatching_Operation (Subp)
6900 or else not Is_Interface (Find_Dispatching_Type (Subp))
6904 -- Entries and procedures can override abstract or null
6905 -- interface procedures
6907 elsif (Ekind (Def_Id) = E_Procedure
6908 or else Ekind (Def_Id) = E_Entry)
6909 and then Ekind (Subp) = E_Procedure
6910 and then Matches_Prefixed_View_Profile
6911 (Parameter_Specifications (Parent (Def_Id)),
6912 Parameter_Specifications (Parent (Subp)))
6916 -- For an overridden subprogram Subp, check whether the mode
6917 -- of its first parameter is correct depending on the kind
6918 -- of synchronized type.
6921 Formal : constant Node_Id := First_Formal (Candidate);
6924 -- In order for an entry or a protected procedure to
6925 -- override, the first parameter of the overridden
6926 -- routine must be of mode "out", "in out" or
6927 -- access-to-variable.
6929 if (Ekind (Candidate) = E_Entry
6930 or else Ekind (Candidate) = E_Procedure)
6931 and then Is_Protected_Type (Typ)
6932 and then Ekind (Formal) /= E_In_Out_Parameter
6933 and then Ekind (Formal) /= E_Out_Parameter
6934 and then Nkind (Parameter_Type (Parent (Formal)))
6935 /= N_Access_Definition
6939 -- All other cases are OK since a task entry or routine
6940 -- does not have a restriction on the mode of the first
6941 -- parameter of the overridden interface routine.
6944 Overridden_Subp := Candidate;
6949 -- Functions can override abstract interface functions
6951 elsif Ekind (Def_Id) = E_Function
6952 and then Ekind (Subp) = E_Function
6953 and then Matches_Prefixed_View_Profile
6954 (Parameter_Specifications (Parent (Def_Id)),
6955 Parameter_Specifications (Parent (Subp)))
6956 and then Etype (Result_Definition (Parent (Def_Id))) =
6957 Etype (Result_Definition (Parent (Subp)))
6959 Overridden_Subp := Subp;
6963 Hom := Homonym (Hom);
6966 -- After examining all candidates for overriding, we are
6967 -- left with the best match which is a mode incompatible
6968 -- interface routine. Do not emit an error if the Expander
6969 -- is active since this error will be detected later on
6970 -- after all concurrent types are expanded and all wrappers
6971 -- are built. This check is meant for spec-only
6974 if Present (Candidate)
6975 and then not Expander_Active
6978 Find_Parameter_Type (Parent (First_Formal (Candidate)));
6980 -- Def_Id is primitive of a protected type, declared
6981 -- inside the type, and the candidate is primitive of a
6982 -- limited or synchronized interface.
6985 and then Is_Protected_Type (Typ)
6987 (Is_Limited_Interface (Iface_Typ)
6988 or else Is_Protected_Interface (Iface_Typ)
6989 or else Is_Synchronized_Interface (Iface_Typ)
6990 or else Is_Task_Interface (Iface_Typ))
6992 -- Must reword this message, comma before to in -gnatj
6996 ("first formal of & must be of mode `OUT`, `IN OUT`"
6997 & " or access-to-variable", Typ, Candidate);
6999 ("\to be overridden by protected procedure or entry "
7000 & "(RM 9.4(11.9/2))", Typ);
7004 Overridden_Subp := Candidate;
7007 end Check_Synchronized_Overriding;
7009 ----------------------------
7010 -- Is_Private_Declaration --
7011 ----------------------------
7013 function Is_Private_Declaration (E : Entity_Id) return Boolean is
7014 Priv_Decls : List_Id;
7015 Decl : constant Node_Id := Unit_Declaration_Node (E);
7018 if Is_Package_Or_Generic_Package (Current_Scope)
7019 and then In_Private_Part (Current_Scope)
7022 Private_Declarations (
7023 Specification (Unit_Declaration_Node (Current_Scope)));
7025 return In_Package_Body (Current_Scope)
7027 (Is_List_Member (Decl)
7028 and then List_Containing (Decl) = Priv_Decls)
7029 or else (Nkind (Parent (Decl)) = N_Package_Specification
7030 and then not Is_Compilation_Unit (
7031 Defining_Entity (Parent (Decl)))
7032 and then List_Containing (Parent (Parent (Decl)))
7037 end Is_Private_Declaration;
7039 --------------------------
7040 -- Is_Overriding_Alias --
7041 --------------------------
7043 function Is_Overriding_Alias
7045 New_E : Entity_Id) return Boolean
7047 AO : constant Entity_Id := Alias (Old_E);
7048 AN : constant Entity_Id := Alias (New_E);
7051 return Scope (AO) /= Scope (AN)
7052 or else No (DTC_Entity (AO))
7053 or else No (DTC_Entity (AN))
7054 or else DT_Position (AO) = DT_Position (AN);
7055 end Is_Overriding_Alias;
7057 -- Start of processing for New_Overloaded_Entity
7060 -- We need to look for an entity that S may override. This must be a
7061 -- homonym in the current scope, so we look for the first homonym of
7062 -- S in the current scope as the starting point for the search.
7064 E := Current_Entity_In_Scope (S);
7066 -- If there is no homonym then this is definitely not overriding
7069 Enter_Overloaded_Entity (S);
7070 Check_Dispatching_Operation (S, Empty);
7071 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
7073 -- If subprogram has an explicit declaration, check whether it
7074 -- has an overriding indicator.
7076 if Comes_From_Source (S) then
7077 Check_Synchronized_Overriding (S, Overridden_Subp);
7078 Check_Overriding_Indicator
7079 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
7082 -- If there is a homonym that is not overloadable, then we have an
7083 -- error, except for the special cases checked explicitly below.
7085 elsif not Is_Overloadable (E) then
7087 -- Check for spurious conflict produced by a subprogram that has the
7088 -- same name as that of the enclosing generic package. The conflict
7089 -- occurs within an instance, between the subprogram and the renaming
7090 -- declaration for the package. After the subprogram, the package
7091 -- renaming declaration becomes hidden.
7093 if Ekind (E) = E_Package
7094 and then Present (Renamed_Object (E))
7095 and then Renamed_Object (E) = Current_Scope
7096 and then Nkind (Parent (Renamed_Object (E))) =
7097 N_Package_Specification
7098 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
7101 Set_Is_Immediately_Visible (E, False);
7102 Enter_Overloaded_Entity (S);
7103 Set_Homonym (S, Homonym (E));
7104 Check_Dispatching_Operation (S, Empty);
7105 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
7107 -- If the subprogram is implicit it is hidden by the previous
7108 -- declaration. However if it is dispatching, it must appear in the
7109 -- dispatch table anyway, because it can be dispatched to even if it
7110 -- cannot be called directly.
7112 elsif Present (Alias (S))
7113 and then not Comes_From_Source (S)
7115 Set_Scope (S, Current_Scope);
7117 if Is_Dispatching_Operation (Alias (S)) then
7118 Check_Dispatching_Operation (S, Empty);
7124 Error_Msg_Sloc := Sloc (E);
7126 -- Generate message, with useful additional warning if in generic
7128 if Is_Generic_Unit (E) then
7129 Error_Msg_N ("previous generic unit cannot be overloaded", S);
7130 Error_Msg_N ("\& conflicts with declaration#", S);
7132 Error_Msg_N ("& conflicts with declaration#", S);
7138 -- E exists and is overloadable
7141 -- Ada 2005 (AI-251): Derivation of abstract interface primitives
7142 -- need no check against the homonym chain. They are directly added
7143 -- to the list of primitive operations of Derived_Type.
7145 if Ada_Version >= Ada_05
7146 and then Present (Derived_Type)
7147 and then Is_Dispatching_Operation (Alias (S))
7148 and then Present (Find_Dispatching_Type (Alias (S)))
7149 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
7151 goto Add_New_Entity;
7154 Check_Synchronized_Overriding (S, Overridden_Subp);
7156 -- Loop through E and its homonyms to determine if any of them is
7157 -- the candidate for overriding by S.
7159 while Present (E) loop
7161 -- Definitely not interesting if not in the current scope
7163 if Scope (E) /= Current_Scope then
7166 -- Check if we have type conformance
7168 elsif Type_Conformant (E, S) then
7170 -- If the old and new entities have the same profile and one
7171 -- is not the body of the other, then this is an error, unless
7172 -- one of them is implicitly declared.
7174 -- There are some cases when both can be implicit, for example
7175 -- when both a literal and a function that overrides it are
7176 -- inherited in a derivation, or when an inherited operation
7177 -- of a tagged full type overrides the inherited operation of
7178 -- a private extension. Ada 83 had a special rule for the
7179 -- literal case. In Ada95, the later implicit operation hides
7180 -- the former, and the literal is always the former. In the
7181 -- odd case where both are derived operations declared at the
7182 -- same point, both operations should be declared, and in that
7183 -- case we bypass the following test and proceed to the next
7184 -- part. This can only occur for certain obscure cases in
7185 -- instances, when an operation on a type derived from a formal
7186 -- private type does not override a homograph inherited from
7187 -- the actual. In subsequent derivations of such a type, the
7188 -- DT positions of these operations remain distinct, if they
7191 if Present (Alias (S))
7192 and then (No (Alias (E))
7193 or else Comes_From_Source (E)
7194 or else Is_Abstract_Subprogram (S)
7196 (Is_Dispatching_Operation (E)
7197 and then Is_Overriding_Alias (E, S)))
7198 and then Ekind (E) /= E_Enumeration_Literal
7201 -- When an derived operation is overloaded it may be due to
7202 -- the fact that the full view of a private extension
7203 -- re-inherits. It has to be dealt with.
7205 if Is_Package_Or_Generic_Package (Current_Scope)
7206 and then In_Private_Part (Current_Scope)
7208 Check_Operation_From_Private_View (S, E);
7211 -- In any case the implicit operation remains hidden by
7212 -- the existing declaration, which is overriding.
7214 Set_Is_Overriding_Operation (E);
7216 if Comes_From_Source (E) then
7217 Check_Overriding_Indicator (E, S, Is_Primitive => False);
7219 -- Indicate that E overrides the operation from which
7222 if Present (Alias (S)) then
7223 Set_Overridden_Operation (E, Alias (S));
7225 Set_Overridden_Operation (E, S);
7231 -- Within an instance, the renaming declarations for
7232 -- actual subprograms may become ambiguous, but they do
7233 -- not hide each other.
7235 elsif Ekind (E) /= E_Entry
7236 and then not Comes_From_Source (E)
7237 and then not Is_Generic_Instance (E)
7238 and then (Present (Alias (E))
7239 or else Is_Intrinsic_Subprogram (E))
7240 and then (not In_Instance
7241 or else No (Parent (E))
7242 or else Nkind (Unit_Declaration_Node (E)) /=
7243 N_Subprogram_Renaming_Declaration)
7245 -- A subprogram child unit is not allowed to override
7246 -- an inherited subprogram (10.1.1(20)).
7248 if Is_Child_Unit (S) then
7250 ("child unit overrides inherited subprogram in parent",
7255 if Is_Non_Overriding_Operation (E, S) then
7256 Enter_Overloaded_Entity (S);
7257 if No (Derived_Type)
7258 or else Is_Tagged_Type (Derived_Type)
7260 Check_Dispatching_Operation (S, Empty);
7266 -- E is a derived operation or an internal operator which
7267 -- is being overridden. Remove E from further visibility.
7268 -- Furthermore, if E is a dispatching operation, it must be
7269 -- replaced in the list of primitive operations of its type
7270 -- (see Override_Dispatching_Operation).
7272 Overridden_Subp := E;
7278 Prev := First_Entity (Current_Scope);
7280 while Present (Prev)
7281 and then Next_Entity (Prev) /= E
7286 -- It is possible for E to be in the current scope and
7287 -- yet not in the entity chain. This can only occur in a
7288 -- generic context where E is an implicit concatenation
7289 -- in the formal part, because in a generic body the
7290 -- entity chain starts with the formals.
7293 (Present (Prev) or else Chars (E) = Name_Op_Concat);
7295 -- E must be removed both from the entity_list of the
7296 -- current scope, and from the visibility chain
7298 if Debug_Flag_E then
7299 Write_Str ("Override implicit operation ");
7300 Write_Int (Int (E));
7304 -- If E is a predefined concatenation, it stands for four
7305 -- different operations. As a result, a single explicit
7306 -- declaration does not hide it. In a possible ambiguous
7307 -- situation, Disambiguate chooses the user-defined op,
7308 -- so it is correct to retain the previous internal one.
7310 if Chars (E) /= Name_Op_Concat
7311 or else Ekind (E) /= E_Operator
7313 -- For nondispatching derived operations that are
7314 -- overridden by a subprogram declared in the private
7315 -- part of a package, we retain the derived
7316 -- subprogram but mark it as not immediately visible.
7317 -- If the derived operation was declared in the
7318 -- visible part then this ensures that it will still
7319 -- be visible outside the package with the proper
7320 -- signature (calls from outside must also be
7321 -- directed to this version rather than the
7322 -- overriding one, unlike the dispatching case).
7323 -- Calls from inside the package will still resolve
7324 -- to the overriding subprogram since the derived one
7325 -- is marked as not visible within the package.
7327 -- If the private operation is dispatching, we achieve
7328 -- the overriding by keeping the implicit operation
7329 -- but setting its alias to be the overriding one. In
7330 -- this fashion the proper body is executed in all
7331 -- cases, but the original signature is used outside
7334 -- If the overriding is not in the private part, we
7335 -- remove the implicit operation altogether.
7337 if Is_Private_Declaration (S) then
7339 if not Is_Dispatching_Operation (E) then
7340 Set_Is_Immediately_Visible (E, False);
7342 -- Work done in Override_Dispatching_Operation,
7343 -- so nothing else need to be done here.
7349 -- Find predecessor of E in Homonym chain
7351 if E = Current_Entity (E) then
7354 Prev_Vis := Current_Entity (E);
7355 while Homonym (Prev_Vis) /= E loop
7356 Prev_Vis := Homonym (Prev_Vis);
7360 if Prev_Vis /= Empty then
7362 -- Skip E in the visibility chain
7364 Set_Homonym (Prev_Vis, Homonym (E));
7367 Set_Name_Entity_Id (Chars (E), Homonym (E));
7370 Set_Next_Entity (Prev, Next_Entity (E));
7372 if No (Next_Entity (Prev)) then
7373 Set_Last_Entity (Current_Scope, Prev);
7379 Enter_Overloaded_Entity (S);
7380 Set_Is_Overriding_Operation (S);
7381 Check_Overriding_Indicator (S, E, Is_Primitive => True);
7383 -- Indicate that S overrides the operation from which
7386 if Comes_From_Source (S) then
7387 if Present (Alias (E)) then
7388 Set_Overridden_Operation (S, Alias (E));
7390 Set_Overridden_Operation (S, E);
7394 if Is_Dispatching_Operation (E) then
7396 -- An overriding dispatching subprogram inherits the
7397 -- convention of the overridden subprogram (by
7400 Set_Convention (S, Convention (E));
7401 Check_Dispatching_Operation (S, E);
7404 Check_Dispatching_Operation (S, Empty);
7407 Check_For_Primitive_Subprogram
7408 (Is_Primitive_Subp, Is_Overriding => True);
7409 goto Check_Inequality;
7412 -- Apparent redeclarations in instances can occur when two
7413 -- formal types get the same actual type. The subprograms in
7414 -- in the instance are legal, even if not callable from the
7415 -- outside. Calls from within are disambiguated elsewhere.
7416 -- For dispatching operations in the visible part, the usual
7417 -- rules apply, and operations with the same profile are not
7420 elsif (In_Instance_Visible_Part
7421 and then not Is_Dispatching_Operation (E))
7422 or else In_Instance_Not_Visible
7426 -- Here we have a real error (identical profile)
7429 Error_Msg_Sloc := Sloc (E);
7431 -- Avoid cascaded errors if the entity appears in
7432 -- subsequent calls.
7434 Set_Scope (S, Current_Scope);
7436 -- Generate error, with extra useful warning for the case
7437 -- of a generic instance with no completion.
7439 if Is_Generic_Instance (S)
7440 and then not Has_Completion (E)
7443 ("instantiation cannot provide body for&", S);
7444 Error_Msg_N ("\& conflicts with declaration#", S);
7446 Error_Msg_N ("& conflicts with declaration#", S);
7453 -- If one subprogram has an access parameter and the other
7454 -- a parameter of an access type, calls to either might be
7455 -- ambiguous. Verify that parameters match except for the
7456 -- access parameter.
7458 if May_Hide_Profile then
7463 F1 := First_Formal (S);
7464 F2 := First_Formal (E);
7465 while Present (F1) and then Present (F2) loop
7466 if Is_Access_Type (Etype (F1)) then
7467 if not Is_Access_Type (Etype (F2))
7468 or else not Conforming_Types
7469 (Designated_Type (Etype (F1)),
7470 Designated_Type (Etype (F2)),
7473 May_Hide_Profile := False;
7477 not Conforming_Types
7478 (Etype (F1), Etype (F2), Type_Conformant)
7480 May_Hide_Profile := False;
7491 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
7502 -- On exit, we know that S is a new entity
7504 Enter_Overloaded_Entity (S);
7505 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
7506 Check_Overriding_Indicator
7507 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
7509 -- If S is a derived operation for an untagged type then by
7510 -- definition it's not a dispatching operation (even if the parent
7511 -- operation was dispatching), so we don't call
7512 -- Check_Dispatching_Operation in that case.
7514 if No (Derived_Type)
7515 or else Is_Tagged_Type (Derived_Type)
7517 Check_Dispatching_Operation (S, Empty);
7521 -- If this is a user-defined equality operator that is not a derived
7522 -- subprogram, create the corresponding inequality. If the operation is
7523 -- dispatching, the expansion is done elsewhere, and we do not create
7524 -- an explicit inequality operation.
7526 <<Check_Inequality>>
7527 if Chars (S) = Name_Op_Eq
7528 and then Etype (S) = Standard_Boolean
7529 and then Present (Parent (S))
7530 and then not Is_Dispatching_Operation (S)
7532 Make_Inequality_Operator (S);
7534 end New_Overloaded_Entity;
7536 ---------------------
7537 -- Process_Formals --
7538 ---------------------
7540 procedure Process_Formals
7542 Related_Nod : Node_Id)
7544 Param_Spec : Node_Id;
7546 Formal_Type : Entity_Id;
7550 Num_Out_Params : Nat := 0;
7551 First_Out_Param : Entity_Id := Empty;
7552 -- Used for setting Is_Only_Out_Parameter
7554 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
7555 -- Check whether the default has a class-wide type. After analysis the
7556 -- default has the type of the formal, so we must also check explicitly
7557 -- for an access attribute.
7559 ---------------------------
7560 -- Is_Class_Wide_Default --
7561 ---------------------------
7563 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
7565 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
7566 or else (Nkind (D) = N_Attribute_Reference
7567 and then Attribute_Name (D) = Name_Access
7568 and then Is_Class_Wide_Type (Etype (Prefix (D))));
7569 end Is_Class_Wide_Default;
7571 -- Start of processing for Process_Formals
7574 -- In order to prevent premature use of the formals in the same formal
7575 -- part, the Ekind is left undefined until all default expressions are
7576 -- analyzed. The Ekind is established in a separate loop at the end.
7578 Param_Spec := First (T);
7579 while Present (Param_Spec) loop
7580 Formal := Defining_Identifier (Param_Spec);
7581 Set_Never_Set_In_Source (Formal, True);
7582 Enter_Name (Formal);
7584 -- Case of ordinary parameters
7586 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
7587 Find_Type (Parameter_Type (Param_Spec));
7588 Ptype := Parameter_Type (Param_Spec);
7590 if Ptype = Error then
7594 Formal_Type := Entity (Ptype);
7596 if Is_Incomplete_Type (Formal_Type)
7598 (Is_Class_Wide_Type (Formal_Type)
7599 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
7601 -- Ada 2005 (AI-326): Tagged incomplete types allowed
7603 if Is_Tagged_Type (Formal_Type) then
7606 -- Special handling of Value_Type for CIL case
7608 elsif Is_Value_Type (Formal_Type) then
7611 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
7612 N_Access_Procedure_Definition)
7614 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
7616 -- An incomplete type that is not tagged is allowed in an
7617 -- access-to-subprogram type only if it is a local declaration
7618 -- with a forthcoming completion (3.10.1 (9.2/2)).
7620 elsif Scope (Formal_Type) /= Scope (Current_Scope) then
7622 ("invalid use of limited view of type", Param_Spec);
7625 elsif Ekind (Formal_Type) = E_Void then
7626 Error_Msg_NE ("premature use of&",
7627 Parameter_Type (Param_Spec), Formal_Type);
7630 -- Ada 2005 (AI-231): Create and decorate an internal subtype
7631 -- declaration corresponding to the null-excluding type of the
7632 -- formal in the enclosing scope. Finally, replace the parameter
7633 -- type of the formal with the internal subtype.
7635 if Ada_Version >= Ada_05
7636 and then Null_Exclusion_Present (Param_Spec)
7638 if not Is_Access_Type (Formal_Type) then
7640 ("`NOT NULL` allowed only for an access type", Param_Spec);
7643 if Can_Never_Be_Null (Formal_Type)
7644 and then Comes_From_Source (Related_Nod)
7647 ("`NOT NULL` not allowed (& already excludes null)",
7653 Create_Null_Excluding_Itype
7655 Related_Nod => Related_Nod,
7656 Scope_Id => Scope (Current_Scope));
7658 -- If the designated type of the itype is an itype we
7659 -- decorate it with the Has_Delayed_Freeze attribute to
7660 -- avoid problems with the backend.
7663 -- type T is access procedure;
7664 -- procedure Op (O : not null T);
7666 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
7667 Set_Has_Delayed_Freeze (Formal_Type);
7672 -- An access formal type
7676 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
7678 -- No need to continue if we already notified errors
7680 if not Present (Formal_Type) then
7684 -- Ada 2005 (AI-254)
7687 AD : constant Node_Id :=
7688 Access_To_Subprogram_Definition
7689 (Parameter_Type (Param_Spec));
7691 if Present (AD) and then Protected_Present (AD) then
7693 Replace_Anonymous_Access_To_Protected_Subprogram
7699 Set_Etype (Formal, Formal_Type);
7700 Default := Expression (Param_Spec);
7702 if Present (Default) then
7703 if Out_Present (Param_Spec) then
7705 ("default initialization only allowed for IN parameters",
7709 -- Do the special preanalysis of the expression (see section on
7710 -- "Handling of Default Expressions" in the spec of package Sem).
7712 Preanalyze_Spec_Expression (Default, Formal_Type);
7714 -- An access to constant cannot be the default for
7715 -- an access parameter that is an access to variable.
7717 if Ekind (Formal_Type) = E_Anonymous_Access_Type
7718 and then not Is_Access_Constant (Formal_Type)
7719 and then Is_Access_Type (Etype (Default))
7720 and then Is_Access_Constant (Etype (Default))
7723 ("formal that is access to variable cannot be initialized " &
7724 "with an access-to-constant expression", Default);
7727 -- Check that the designated type of an access parameter's default
7728 -- is not a class-wide type unless the parameter's designated type
7729 -- is also class-wide.
7731 if Ekind (Formal_Type) = E_Anonymous_Access_Type
7732 and then not From_With_Type (Formal_Type)
7733 and then Is_Class_Wide_Default (Default)
7734 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
7737 ("access to class-wide expression not allowed here", Default);
7741 -- Ada 2005 (AI-231): Static checks
7743 if Ada_Version >= Ada_05
7744 and then Is_Access_Type (Etype (Formal))
7745 and then Can_Never_Be_Null (Etype (Formal))
7747 Null_Exclusion_Static_Checks (Param_Spec);
7754 -- If this is the formal part of a function specification, analyze the
7755 -- subtype mark in the context where the formals are visible but not
7756 -- yet usable, and may hide outer homographs.
7758 if Nkind (Related_Nod) = N_Function_Specification then
7759 Analyze_Return_Type (Related_Nod);
7762 -- Now set the kind (mode) of each formal
7764 Param_Spec := First (T);
7766 while Present (Param_Spec) loop
7767 Formal := Defining_Identifier (Param_Spec);
7768 Set_Formal_Mode (Formal);
7770 if Ekind (Formal) = E_In_Parameter then
7771 Set_Default_Value (Formal, Expression (Param_Spec));
7773 if Present (Expression (Param_Spec)) then
7774 Default := Expression (Param_Spec);
7776 if Is_Scalar_Type (Etype (Default)) then
7778 (Parameter_Type (Param_Spec)) /= N_Access_Definition
7780 Formal_Type := Entity (Parameter_Type (Param_Spec));
7783 Formal_Type := Access_Definition
7784 (Related_Nod, Parameter_Type (Param_Spec));
7787 Apply_Scalar_Range_Check (Default, Formal_Type);
7791 elsif Ekind (Formal) = E_Out_Parameter then
7792 Num_Out_Params := Num_Out_Params + 1;
7794 if Num_Out_Params = 1 then
7795 First_Out_Param := Formal;
7798 elsif Ekind (Formal) = E_In_Out_Parameter then
7799 Num_Out_Params := Num_Out_Params + 1;
7805 if Present (First_Out_Param) and then Num_Out_Params = 1 then
7806 Set_Is_Only_Out_Parameter (First_Out_Param);
7808 end Process_Formals;
7814 procedure Process_PPCs
7816 Spec_Id : Entity_Id;
7817 Body_Id : Entity_Id)
7819 Loc : constant Source_Ptr := Sloc (N);
7821 Plist : List_Id := No_List;
7825 function Grab_PPC (Nam : Name_Id) return Node_Id;
7826 -- Prag contains an analyzed precondition or postcondition pragma.
7827 -- This function copies the pragma, changes it to the corresponding
7828 -- Check pragma and returns the Check pragma as the result. The
7829 -- argument Nam is either Name_Precondition or Name_Postcondition.
7835 function Grab_PPC (Nam : Name_Id) return Node_Id is
7836 CP : constant Node_Id := New_Copy_Tree (Prag);
7839 -- Set Analyzed to false, since we want to reanalyze the check
7840 -- procedure. Note that it is only at the outer level that we
7841 -- do this fiddling, for the spec cases, the already preanalyzed
7842 -- parameters are not affected.
7844 -- For a postcondition pragma within a generic, preserve the pragma
7845 -- for later expansion.
7847 Set_Analyzed (CP, False);
7849 if Nam = Name_Postcondition
7850 and then not Expander_Active
7855 -- Change pragma into corresponding pragma Check
7857 Prepend_To (Pragma_Argument_Associations (CP),
7858 Make_Pragma_Argument_Association (Sloc (Prag),
7860 Make_Identifier (Loc,
7862 Set_Pragma_Identifier (CP,
7863 Make_Identifier (Sloc (Prag),
7864 Chars => Name_Check));
7869 -- Start of processing for Process_PPCs
7872 -- Nothing to do if we are not generating code
7874 if Operating_Mode /= Generate_Code then
7878 -- Grab preconditions from spec
7880 if Present (Spec_Id) then
7882 -- Loop through PPC pragmas from spec. Note that preconditions from
7883 -- the body will be analyzed and converted when we scan the body
7884 -- declarations below.
7886 Prag := Spec_PPC_List (Spec_Id);
7887 while Present (Prag) loop
7888 if Pragma_Name (Prag) = Name_Precondition
7889 and then PPC_Enabled (Prag)
7891 -- Add pragma Check at the start of the declarations of N.
7892 -- Note that this processing reverses the order of the list,
7893 -- which is what we want since new entries were chained to
7894 -- the head of the list.
7896 Prepend (Grab_PPC (Name_Precondition), Declarations (N));
7899 Prag := Next_Pragma (Prag);
7903 -- Build postconditions procedure if needed and prepend the following
7904 -- declaration to the start of the declarations for the subprogram.
7906 -- procedure _postconditions [(_Result : resulttype)] is
7908 -- pragma Check (Postcondition, condition [,message]);
7909 -- pragma Check (Postcondition, condition [,message]);
7913 -- First we deal with the postconditions in the body
7915 if Is_Non_Empty_List (Declarations (N)) then
7917 -- Loop through declarations
7919 Prag := First (Declarations (N));
7920 while Present (Prag) loop
7921 if Nkind (Prag) = N_Pragma then
7923 -- If pragma, capture if enabled postcondition, else ignore
7925 if Pragma_Name (Prag) = Name_Postcondition
7926 and then Check_Enabled (Name_Postcondition)
7928 if Plist = No_List then
7929 Plist := Empty_List;
7934 -- If expansion is disabled, as in a generic unit,
7935 -- save pragma for later expansion.
7937 if not Expander_Active then
7938 Prepend (Grab_PPC (Name_Postcondition), Declarations (N));
7940 Append (Grab_PPC (Name_Postcondition), Plist);
7946 -- Not a pragma, if comes from source, then end scan
7948 elsif Comes_From_Source (Prag) then
7951 -- Skip stuff not coming from source
7959 -- Now deal with any postconditions from the spec
7961 if Present (Spec_Id) then
7963 -- Loop through PPC pragmas from spec
7965 Prag := Spec_PPC_List (Spec_Id);
7966 while Present (Prag) loop
7967 if Pragma_Name (Prag) = Name_Postcondition
7968 and then PPC_Enabled (Prag)
7970 if Plist = No_List then
7971 Plist := Empty_List;
7974 if not Expander_Active then
7975 Prepend (Grab_PPC (Name_Postcondition), Declarations (N));
7977 Append (Grab_PPC (Name_Postcondition), Plist);
7981 Prag := Next_Pragma (Prag);
7985 -- If we had any postconditions and expansion is enabled, build
7986 -- the Postconditions procedure.
7989 and then Expander_Active
7991 Subp := Defining_Entity (N);
7993 if Etype (Subp) /= Standard_Void_Type then
7995 Make_Parameter_Specification (Loc,
7996 Defining_Identifier =>
7997 Make_Defining_Identifier (Loc,
7998 Chars => Name_uResult),
7999 Parameter_Type => New_Occurrence_Of (Etype (Subp), Loc)));
8004 Prepend_To (Declarations (N),
8005 Make_Subprogram_Body (Loc,
8007 Make_Procedure_Specification (Loc,
8008 Defining_Unit_Name =>
8009 Make_Defining_Identifier (Loc,
8010 Chars => Name_uPostconditions),
8011 Parameter_Specifications => Parms),
8013 Declarations => Empty_List,
8015 Handled_Statement_Sequence =>
8016 Make_Handled_Sequence_Of_Statements (Loc,
8017 Statements => Plist)));
8019 if Present (Spec_Id) then
8020 Set_Has_Postconditions (Spec_Id);
8022 Set_Has_Postconditions (Body_Id);
8027 ----------------------------
8028 -- Reference_Body_Formals --
8029 ----------------------------
8031 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
8036 if Error_Posted (Spec) then
8040 -- Iterate over both lists. They may be of different lengths if the two
8041 -- specs are not conformant.
8043 Fs := First_Formal (Spec);
8044 Fb := First_Formal (Bod);
8045 while Present (Fs) and then Present (Fb) loop
8046 Generate_Reference (Fs, Fb, 'b');
8049 Style.Check_Identifier (Fb, Fs);
8052 Set_Spec_Entity (Fb, Fs);
8053 Set_Referenced (Fs, False);
8057 end Reference_Body_Formals;
8059 -------------------------
8060 -- Set_Actual_Subtypes --
8061 -------------------------
8063 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
8064 Loc : constant Source_Ptr := Sloc (N);
8068 First_Stmt : Node_Id := Empty;
8069 AS_Needed : Boolean;
8072 -- If this is an empty initialization procedure, no need to create
8073 -- actual subtypes (small optimization).
8075 if Ekind (Subp) = E_Procedure
8076 and then Is_Null_Init_Proc (Subp)
8081 Formal := First_Formal (Subp);
8082 while Present (Formal) loop
8083 T := Etype (Formal);
8085 -- We never need an actual subtype for a constrained formal
8087 if Is_Constrained (T) then
8090 -- If we have unknown discriminants, then we do not need an actual
8091 -- subtype, or more accurately we cannot figure it out! Note that
8092 -- all class-wide types have unknown discriminants.
8094 elsif Has_Unknown_Discriminants (T) then
8097 -- At this stage we have an unconstrained type that may need an
8098 -- actual subtype. For sure the actual subtype is needed if we have
8099 -- an unconstrained array type.
8101 elsif Is_Array_Type (T) then
8104 -- The only other case needing an actual subtype is an unconstrained
8105 -- record type which is an IN parameter (we cannot generate actual
8106 -- subtypes for the OUT or IN OUT case, since an assignment can
8107 -- change the discriminant values. However we exclude the case of
8108 -- initialization procedures, since discriminants are handled very
8109 -- specially in this context, see the section entitled "Handling of
8110 -- Discriminants" in Einfo.
8112 -- We also exclude the case of Discrim_SO_Functions (functions used
8113 -- in front end layout mode for size/offset values), since in such
8114 -- functions only discriminants are referenced, and not only are such
8115 -- subtypes not needed, but they cannot always be generated, because
8116 -- of order of elaboration issues.
8118 elsif Is_Record_Type (T)
8119 and then Ekind (Formal) = E_In_Parameter
8120 and then Chars (Formal) /= Name_uInit
8121 and then not Is_Unchecked_Union (T)
8122 and then not Is_Discrim_SO_Function (Subp)
8126 -- All other cases do not need an actual subtype
8132 -- Generate actual subtypes for unconstrained arrays and
8133 -- unconstrained discriminated records.
8136 if Nkind (N) = N_Accept_Statement then
8138 -- If expansion is active, The formal is replaced by a local
8139 -- variable that renames the corresponding entry of the
8140 -- parameter block, and it is this local variable that may
8141 -- require an actual subtype.
8143 if Expander_Active then
8144 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
8146 Decl := Build_Actual_Subtype (T, Formal);
8149 if Present (Handled_Statement_Sequence (N)) then
8151 First (Statements (Handled_Statement_Sequence (N)));
8152 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
8153 Mark_Rewrite_Insertion (Decl);
8155 -- If the accept statement has no body, there will be no
8156 -- reference to the actuals, so no need to compute actual
8163 Decl := Build_Actual_Subtype (T, Formal);
8164 Prepend (Decl, Declarations (N));
8165 Mark_Rewrite_Insertion (Decl);
8168 -- The declaration uses the bounds of an existing object, and
8169 -- therefore needs no constraint checks.
8171 Analyze (Decl, Suppress => All_Checks);
8173 -- We need to freeze manually the generated type when it is
8174 -- inserted anywhere else than in a declarative part.
8176 if Present (First_Stmt) then
8177 Insert_List_Before_And_Analyze (First_Stmt,
8178 Freeze_Entity (Defining_Identifier (Decl), Loc));
8181 if Nkind (N) = N_Accept_Statement
8182 and then Expander_Active
8184 Set_Actual_Subtype (Renamed_Object (Formal),
8185 Defining_Identifier (Decl));
8187 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
8191 Next_Formal (Formal);
8193 end Set_Actual_Subtypes;
8195 ---------------------
8196 -- Set_Formal_Mode --
8197 ---------------------
8199 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
8200 Spec : constant Node_Id := Parent (Formal_Id);
8203 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
8204 -- since we ensure that corresponding actuals are always valid at the
8205 -- point of the call.
8207 if Out_Present (Spec) then
8208 if Ekind (Scope (Formal_Id)) = E_Function
8209 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
8211 Error_Msg_N ("functions can only have IN parameters", Spec);
8212 Set_Ekind (Formal_Id, E_In_Parameter);
8214 elsif In_Present (Spec) then
8215 Set_Ekind (Formal_Id, E_In_Out_Parameter);
8218 Set_Ekind (Formal_Id, E_Out_Parameter);
8219 Set_Never_Set_In_Source (Formal_Id, True);
8220 Set_Is_True_Constant (Formal_Id, False);
8221 Set_Current_Value (Formal_Id, Empty);
8225 Set_Ekind (Formal_Id, E_In_Parameter);
8228 -- Set Is_Known_Non_Null for access parameters since the language
8229 -- guarantees that access parameters are always non-null. We also set
8230 -- Can_Never_Be_Null, since there is no way to change the value.
8232 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
8234 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
8235 -- null; In Ada 2005, only if then null_exclusion is explicit.
8237 if Ada_Version < Ada_05
8238 or else Can_Never_Be_Null (Etype (Formal_Id))
8240 Set_Is_Known_Non_Null (Formal_Id);
8241 Set_Can_Never_Be_Null (Formal_Id);
8244 -- Ada 2005 (AI-231): Null-exclusion access subtype
8246 elsif Is_Access_Type (Etype (Formal_Id))
8247 and then Can_Never_Be_Null (Etype (Formal_Id))
8249 Set_Is_Known_Non_Null (Formal_Id);
8252 Set_Mechanism (Formal_Id, Default_Mechanism);
8253 Set_Formal_Validity (Formal_Id);
8254 end Set_Formal_Mode;
8256 -------------------------
8257 -- Set_Formal_Validity --
8258 -------------------------
8260 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
8262 -- If no validity checking, then we cannot assume anything about the
8263 -- validity of parameters, since we do not know there is any checking
8264 -- of the validity on the call side.
8266 if not Validity_Checks_On then
8269 -- If validity checking for parameters is enabled, this means we are
8270 -- not supposed to make any assumptions about argument values.
8272 elsif Validity_Check_Parameters then
8275 -- If we are checking in parameters, we will assume that the caller is
8276 -- also checking parameters, so we can assume the parameter is valid.
8278 elsif Ekind (Formal_Id) = E_In_Parameter
8279 and then Validity_Check_In_Params
8281 Set_Is_Known_Valid (Formal_Id, True);
8283 -- Similar treatment for IN OUT parameters
8285 elsif Ekind (Formal_Id) = E_In_Out_Parameter
8286 and then Validity_Check_In_Out_Params
8288 Set_Is_Known_Valid (Formal_Id, True);
8290 end Set_Formal_Validity;
8292 ------------------------
8293 -- Subtype_Conformant --
8294 ------------------------
8296 function Subtype_Conformant
8297 (New_Id : Entity_Id;
8299 Skip_Controlling_Formals : Boolean := False) return Boolean
8303 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
8304 Skip_Controlling_Formals => Skip_Controlling_Formals);
8306 end Subtype_Conformant;
8308 ---------------------
8309 -- Type_Conformant --
8310 ---------------------
8312 function Type_Conformant
8313 (New_Id : Entity_Id;
8315 Skip_Controlling_Formals : Boolean := False) return Boolean
8319 May_Hide_Profile := False;
8322 (New_Id, Old_Id, Type_Conformant, False, Result,
8323 Skip_Controlling_Formals => Skip_Controlling_Formals);
8325 end Type_Conformant;
8327 -------------------------------
8328 -- Valid_Operator_Definition --
8329 -------------------------------
8331 procedure Valid_Operator_Definition (Designator : Entity_Id) is
8334 Id : constant Name_Id := Chars (Designator);
8338 F := First_Formal (Designator);
8339 while Present (F) loop
8342 if Present (Default_Value (F)) then
8344 ("default values not allowed for operator parameters",
8351 -- Verify that user-defined operators have proper number of arguments
8352 -- First case of operators which can only be unary
8355 or else Id = Name_Op_Abs
8359 -- Case of operators which can be unary or binary
8361 elsif Id = Name_Op_Add
8362 or Id = Name_Op_Subtract
8364 N_OK := (N in 1 .. 2);
8366 -- All other operators can only be binary
8374 ("incorrect number of arguments for operator", Designator);
8378 and then Base_Type (Etype (Designator)) = Standard_Boolean
8379 and then not Is_Intrinsic_Subprogram (Designator)
8382 ("explicit definition of inequality not allowed", Designator);
8384 end Valid_Operator_Definition;