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 definately 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",
1728 end Verify_Overriding_Indicator;
1730 -- Start of processing for Analyze_Subprogram_Body
1733 if Debug_Flag_C then
1734 Write_Str ("==== Compiling subprogram body ");
1735 Write_Name (Chars (Body_Id));
1736 Write_Str (" from ");
1737 Write_Location (Loc);
1741 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1743 -- Generic subprograms are handled separately. They always have a
1744 -- generic specification. Determine whether current scope has a
1745 -- previous declaration.
1747 -- If the subprogram body is defined within an instance of the same
1748 -- name, the instance appears as a package renaming, and will be hidden
1749 -- within the subprogram.
1751 if Present (Prev_Id)
1752 and then not Is_Overloadable (Prev_Id)
1753 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
1754 or else Comes_From_Source (Prev_Id))
1756 if Is_Generic_Subprogram (Prev_Id) then
1758 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1759 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1761 Analyze_Generic_Subprogram_Body (N, Spec_Id);
1765 -- Previous entity conflicts with subprogram name. Attempting to
1766 -- enter name will post error.
1768 Enter_Name (Body_Id);
1772 -- Non-generic case, find the subprogram declaration, if one was seen,
1773 -- or enter new overloaded entity in the current scope. If the
1774 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
1775 -- part of the context of one of its subunits. No need to redo the
1778 elsif Prev_Id = Body_Id
1779 and then Has_Completion (Body_Id)
1784 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
1786 if Nkind (N) = N_Subprogram_Body_Stub
1787 or else No (Corresponding_Spec (N))
1789 if Is_Private_Concurrent_Primitive (Body_Id) then
1790 Spec_Id := Disambiguate_Spec;
1792 Spec_Id := Find_Corresponding_Spec (N);
1795 -- If this is a duplicate body, no point in analyzing it
1797 if Error_Posted (N) then
1801 -- A subprogram body should cause freezing of its own declaration,
1802 -- but if there was no previous explicit declaration, then the
1803 -- subprogram will get frozen too late (there may be code within
1804 -- the body that depends on the subprogram having been frozen,
1805 -- such as uses of extra formals), so we force it to be frozen
1806 -- here. Same holds if the body and spec are compilation units.
1807 -- Finally, if the return type is an anonymous access to protected
1808 -- subprogram, it must be frozen before the body because its
1809 -- expansion has generated an equivalent type that is used when
1810 -- elaborating the body.
1812 if No (Spec_Id) then
1813 Freeze_Before (N, Body_Id);
1815 elsif Nkind (Parent (N)) = N_Compilation_Unit then
1816 Freeze_Before (N, Spec_Id);
1818 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
1819 Freeze_Before (N, Etype (Body_Id));
1823 Spec_Id := Corresponding_Spec (N);
1827 -- Do not inline any subprogram that contains nested subprograms, since
1828 -- the backend inlining circuit seems to generate uninitialized
1829 -- references in this case. We know this happens in the case of front
1830 -- end ZCX support, but it also appears it can happen in other cases as
1831 -- well. The backend often rejects attempts to inline in the case of
1832 -- nested procedures anyway, so little if anything is lost by this.
1833 -- Note that this is test is for the benefit of the back-end. There is
1834 -- a separate test for front-end inlining that also rejects nested
1837 -- Do not do this test if errors have been detected, because in some
1838 -- error cases, this code blows up, and we don't need it anyway if
1839 -- there have been errors, since we won't get to the linker anyway.
1841 if Comes_From_Source (Body_Id)
1842 and then Serious_Errors_Detected = 0
1846 P_Ent := Scope (P_Ent);
1847 exit when No (P_Ent) or else P_Ent = Standard_Standard;
1849 if Is_Subprogram (P_Ent) then
1850 Set_Is_Inlined (P_Ent, False);
1852 if Comes_From_Source (P_Ent)
1853 and then Has_Pragma_Inline (P_Ent)
1856 ("cannot inline& (nested subprogram)?",
1863 Check_Inline_Pragma (Spec_Id);
1865 -- Case of fully private operation in the body of the protected type.
1866 -- We must create a declaration for the subprogram, in order to attach
1867 -- the protected subprogram that will be used in internal calls.
1870 and then Comes_From_Source (N)
1871 and then Is_Protected_Type (Current_Scope)
1880 Formal := First_Formal (Body_Id);
1882 -- The protected operation always has at least one formal, namely
1883 -- the object itself, but it is only placed in the parameter list
1884 -- if expansion is enabled.
1887 or else Expander_Active
1889 Plist := Copy_Parameter_List (Body_Id);
1894 if Nkind (Body_Spec) = N_Procedure_Specification then
1896 Make_Procedure_Specification (Loc,
1897 Defining_Unit_Name =>
1898 Make_Defining_Identifier (Sloc (Body_Id),
1899 Chars => Chars (Body_Id)),
1900 Parameter_Specifications => Plist);
1903 Make_Function_Specification (Loc,
1904 Defining_Unit_Name =>
1905 Make_Defining_Identifier (Sloc (Body_Id),
1906 Chars => Chars (Body_Id)),
1907 Parameter_Specifications => Plist,
1908 Result_Definition =>
1909 New_Occurrence_Of (Etype (Body_Id), Loc));
1913 Make_Subprogram_Declaration (Loc,
1914 Specification => New_Spec);
1915 Insert_Before (N, Decl);
1916 Spec_Id := Defining_Unit_Name (New_Spec);
1918 -- Indicate that the entity comes from source, to ensure that
1919 -- cross-reference information is properly generated. The body
1920 -- itself is rewritten during expansion, and the body entity will
1921 -- not appear in calls to the operation.
1923 Set_Comes_From_Source (Spec_Id, True);
1925 Set_Has_Completion (Spec_Id);
1926 Set_Convention (Spec_Id, Convention_Protected);
1929 elsif Present (Spec_Id) then
1930 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1931 Verify_Overriding_Indicator;
1933 -- In general, the spec will be frozen when we start analyzing the
1934 -- body. However, for internally generated operations, such as
1935 -- wrapper functions for inherited operations with controlling
1936 -- results, the spec may not have been frozen by the time we
1937 -- expand the freeze actions that include the bodies. In particular,
1938 -- extra formals for accessibility or for return-in-place may need
1939 -- to be generated. Freeze nodes, if any, are inserted before the
1942 if not Is_Frozen (Spec_Id)
1943 and then Expander_Active
1945 -- Force the generation of its freezing node to ensure proper
1946 -- management of access types in the backend.
1948 -- This is definitely needed for some cases, but it is not clear
1949 -- why, to be investigated further???
1951 Set_Has_Delayed_Freeze (Spec_Id);
1952 Insert_Actions (N, Freeze_Entity (Spec_Id, Loc));
1956 if Chars (Body_Id) = Name_uPostconditions then
1957 Set_Has_Postconditions (Current_Scope);
1960 -- Place subprogram on scope stack, and make formals visible. If there
1961 -- is a spec, the visible entity remains that of the spec.
1963 if Present (Spec_Id) then
1964 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1966 if Is_Child_Unit (Spec_Id) then
1967 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
1971 Style.Check_Identifier (Body_Id, Spec_Id);
1974 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1975 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1977 if Is_Abstract_Subprogram (Spec_Id) then
1978 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1982 Set_Convention (Body_Id, Convention (Spec_Id));
1983 Set_Has_Completion (Spec_Id);
1985 if Is_Protected_Type (Scope (Spec_Id)) then
1986 Prot_Typ := Scope (Spec_Id);
1989 -- If this is a body generated for a renaming, do not check for
1990 -- full conformance. The check is redundant, because the spec of
1991 -- the body is a copy of the spec in the renaming declaration,
1992 -- and the test can lead to spurious errors on nested defaults.
1994 if Present (Spec_Decl)
1995 and then not Comes_From_Source (N)
1997 (Nkind (Original_Node (Spec_Decl)) =
1998 N_Subprogram_Renaming_Declaration
1999 or else (Present (Corresponding_Body (Spec_Decl))
2001 Nkind (Unit_Declaration_Node
2002 (Corresponding_Body (Spec_Decl))) =
2003 N_Subprogram_Renaming_Declaration))
2010 Fully_Conformant, True, Conformant, Body_Id);
2013 -- If the body is not fully conformant, we have to decide if we
2014 -- should analyze it or not. If it has a really messed up profile
2015 -- then we probably should not analyze it, since we will get too
2016 -- many bogus messages.
2018 -- Our decision is to go ahead in the non-fully conformant case
2019 -- only if it is at least mode conformant with the spec. Note
2020 -- that the call to Check_Fully_Conformant has issued the proper
2021 -- error messages to complain about the lack of conformance.
2024 and then not Mode_Conformant (Body_Id, Spec_Id)
2030 if Spec_Id /= Body_Id then
2031 Reference_Body_Formals (Spec_Id, Body_Id);
2034 if Nkind (N) /= N_Subprogram_Body_Stub then
2035 Set_Corresponding_Spec (N, Spec_Id);
2037 -- Ada 2005 (AI-345): If the operation is a primitive operation
2038 -- of a concurrent type, the type of the first parameter has been
2039 -- replaced with the corresponding record, which is the proper
2040 -- run-time structure to use. However, within the body there may
2041 -- be uses of the formals that depend on primitive operations
2042 -- of the type (in particular calls in prefixed form) for which
2043 -- we need the original concurrent type. The operation may have
2044 -- several controlling formals, so the replacement must be done
2047 if Comes_From_Source (Spec_Id)
2048 and then Present (First_Entity (Spec_Id))
2049 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2050 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2052 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2055 (Corresponding_Concurrent_Type
2056 (Etype (First_Entity (Spec_Id))))
2059 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2063 Form := First_Formal (Spec_Id);
2064 while Present (Form) loop
2065 if Etype (Form) = Typ then
2066 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2074 -- Make the formals visible, and place subprogram on scope stack.
2075 -- This is also the point at which we set Last_Real_Spec_Entity
2076 -- to mark the entities which will not be moved to the body.
2078 Install_Formals (Spec_Id);
2079 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2080 Push_Scope (Spec_Id);
2082 -- Make sure that the subprogram is immediately visible. For
2083 -- child units that have no separate spec this is indispensable.
2084 -- Otherwise it is safe albeit redundant.
2086 Set_Is_Immediately_Visible (Spec_Id);
2089 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2090 Set_Ekind (Body_Id, E_Subprogram_Body);
2091 Set_Scope (Body_Id, Scope (Spec_Id));
2092 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2094 -- Case of subprogram body with no previous spec
2098 and then Comes_From_Source (Body_Id)
2099 and then not Suppress_Style_Checks (Body_Id)
2100 and then not In_Instance
2102 Style.Body_With_No_Spec (N);
2105 New_Overloaded_Entity (Body_Id);
2107 if Nkind (N) /= N_Subprogram_Body_Stub then
2108 Set_Acts_As_Spec (N);
2109 Generate_Definition (Body_Id);
2111 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2112 Generate_Reference_To_Formals (Body_Id);
2113 Install_Formals (Body_Id);
2114 Push_Scope (Body_Id);
2118 -- If the return type is an anonymous access type whose designated type
2119 -- is the limited view of a class-wide type and the non-limited view is
2120 -- available, update the return type accordingly.
2122 if Ada_Version >= Ada_05
2123 and then Comes_From_Source (N)
2130 Rtyp := Etype (Current_Scope);
2132 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2133 Etyp := Directly_Designated_Type (Rtyp);
2135 if Is_Class_Wide_Type (Etyp)
2136 and then From_With_Type (Etyp)
2138 Set_Directly_Designated_Type
2139 (Etype (Current_Scope), Available_View (Etyp));
2145 -- If this is the proper body of a stub, we must verify that the stub
2146 -- conforms to the body, and to the previous spec if one was present.
2147 -- we know already that the body conforms to that spec. This test is
2148 -- only required for subprograms that come from source.
2150 if Nkind (Parent (N)) = N_Subunit
2151 and then Comes_From_Source (N)
2152 and then not Error_Posted (Body_Id)
2153 and then Nkind (Corresponding_Stub (Parent (N))) =
2154 N_Subprogram_Body_Stub
2157 Old_Id : constant Entity_Id :=
2159 (Specification (Corresponding_Stub (Parent (N))));
2161 Conformant : Boolean := False;
2164 if No (Spec_Id) then
2165 Check_Fully_Conformant (Body_Id, Old_Id);
2169 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2171 if not Conformant then
2173 -- The stub was taken to be a new declaration. Indicate
2174 -- that it lacks a body.
2176 Set_Has_Completion (Old_Id, False);
2182 Set_Has_Completion (Body_Id);
2183 Check_Eliminated (Body_Id);
2185 if Nkind (N) = N_Subprogram_Body_Stub then
2188 elsif Present (Spec_Id)
2189 and then Expander_Active
2191 (Has_Pragma_Inline_Always (Spec_Id)
2192 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2194 Build_Body_To_Inline (N, Spec_Id);
2197 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2198 -- if its specification we have to install the private withed units.
2199 -- This holds for child units as well.
2201 if Is_Compilation_Unit (Body_Id)
2202 or else Nkind (Parent (N)) = N_Compilation_Unit
2204 Install_Private_With_Clauses (Body_Id);
2207 Check_Anonymous_Return;
2209 -- Set the Protected_Formal field of each extra formal of the protected
2210 -- subprogram to reference the corresponding extra formal of the
2211 -- subprogram that implements it. For regular formals this occurs when
2212 -- the protected subprogram's declaration is expanded, but the extra
2213 -- formals don't get created until the subprogram is frozen. We need to
2214 -- do this before analyzing the protected subprogram's body so that any
2215 -- references to the original subprogram's extra formals will be changed
2216 -- refer to the implementing subprogram's formals (see Expand_Formal).
2218 if Present (Spec_Id)
2219 and then Is_Protected_Type (Scope (Spec_Id))
2220 and then Present (Protected_Body_Subprogram (Spec_Id))
2223 Impl_Subp : constant Entity_Id :=
2224 Protected_Body_Subprogram (Spec_Id);
2225 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2226 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2228 while Present (Prot_Ext_Formal) loop
2229 pragma Assert (Present (Impl_Ext_Formal));
2230 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2231 Next_Formal_With_Extras (Prot_Ext_Formal);
2232 Next_Formal_With_Extras (Impl_Ext_Formal);
2237 -- Now we can go on to analyze the body
2239 HSS := Handled_Statement_Sequence (N);
2240 Set_Actual_Subtypes (N, Current_Scope);
2242 -- Deal with preconditions and postconditions
2244 Process_PPCs (N, Spec_Id, Body_Id);
2246 -- Add a declaration for the Protection object, renaming declarations
2247 -- for discriminals and privals and finally a declaration for the entry
2248 -- family index (if applicable). This form of early expansion is done
2249 -- when the Expander is active because Install_Private_Data_Declarations
2250 -- references entities which were created during regular expansion.
2253 and then Comes_From_Source (N)
2254 and then Present (Prot_Typ)
2255 and then Present (Spec_Id)
2256 and then not Is_Eliminated (Spec_Id)
2258 Install_Private_Data_Declarations
2259 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2262 -- Analyze the declarations (this call will analyze the precondition
2263 -- Check pragmas we prepended to the list, as well as the declaration
2264 -- of the _Postconditions procedure).
2266 Analyze_Declarations (Declarations (N));
2268 -- Check completion, and analyze the statements
2271 Inspect_Deferred_Constant_Completion (Declarations (N));
2274 -- Deal with end of scope processing for the body
2276 Process_End_Label (HSS, 't', Current_Scope);
2278 Check_Subprogram_Order (N);
2279 Set_Analyzed (Body_Id);
2281 -- If we have a separate spec, then the analysis of the declarations
2282 -- caused the entities in the body to be chained to the spec id, but
2283 -- we want them chained to the body id. Only the formal parameters
2284 -- end up chained to the spec id in this case.
2286 if Present (Spec_Id) then
2288 -- We must conform to the categorization of our spec
2290 Validate_Categorization_Dependency (N, Spec_Id);
2292 -- And if this is a child unit, the parent units must conform
2294 if Is_Child_Unit (Spec_Id) then
2295 Validate_Categorization_Dependency
2296 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2299 -- Here is where we move entities from the spec to the body
2301 -- Case where there are entities that stay with the spec
2303 if Present (Last_Real_Spec_Entity) then
2305 -- No body entities (happens when the only real spec entities
2306 -- come from precondition and postcondition pragmas)
2308 if No (Last_Entity (Body_Id)) then
2310 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2312 -- Body entities present (formals), so chain stuff past them
2316 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2319 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2320 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2321 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2323 -- Case where there are no spec entities, in this case there can
2324 -- be no body entities either, so just move everything.
2327 pragma Assert (No (Last_Entity (Body_Id)));
2328 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2329 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2330 Set_First_Entity (Spec_Id, Empty);
2331 Set_Last_Entity (Spec_Id, Empty);
2335 -- If function, check return statements
2337 if Nkind (Body_Spec) = N_Function_Specification then
2342 if Present (Spec_Id) then
2348 if Return_Present (Id) then
2349 Check_Returns (HSS, 'F', Missing_Ret);
2352 Set_Has_Missing_Return (Id);
2355 elsif not Is_Machine_Code_Subprogram (Id)
2356 and then not Body_Deleted
2358 Error_Msg_N ("missing RETURN statement in function body", N);
2362 -- If procedure with No_Return, check returns
2364 elsif Nkind (Body_Spec) = N_Procedure_Specification
2365 and then Present (Spec_Id)
2366 and then No_Return (Spec_Id)
2368 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2371 -- Now we are going to check for variables that are never modified in
2372 -- the body of the procedure. But first we deal with a special case
2373 -- where we want to modify this check. If the body of the subprogram
2374 -- starts with a raise statement or its equivalent, or if the body
2375 -- consists entirely of a null statement, then it is pretty obvious
2376 -- that it is OK to not reference the parameters. For example, this
2377 -- might be the following common idiom for a stubbed function:
2378 -- statement of the procedure raises an exception. In particular this
2379 -- deals with the common idiom of a stubbed function, which might
2380 -- appear as something like
2382 -- function F (A : Integer) return Some_Type;
2385 -- raise Program_Error;
2389 -- Here the purpose of X is simply to satisfy the annoying requirement
2390 -- in Ada that there be at least one return, and we certainly do not
2391 -- want to go posting warnings on X that it is not initialized! On
2392 -- the other hand, if X is entirely unreferenced that should still
2395 -- What we do is to detect these cases, and if we find them, flag the
2396 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2397 -- suppress unwanted warnings. For the case of the function stub above
2398 -- we have a special test to set X as apparently assigned to suppress
2405 -- Skip initial labels (for one thing this occurs when we are in
2406 -- front end ZCX mode, but in any case it is irrelevant), and also
2407 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2409 Stm := First (Statements (HSS));
2410 while Nkind (Stm) = N_Label
2411 or else Nkind (Stm) in N_Push_xxx_Label
2416 -- Do the test on the original statement before expansion
2419 Ostm : constant Node_Id := Original_Node (Stm);
2422 -- If explicit raise statement, turn on flag
2424 if Nkind (Ostm) = N_Raise_Statement then
2425 Set_Trivial_Subprogram (Stm);
2427 -- If null statement, and no following statements, turn on flag
2429 elsif Nkind (Stm) = N_Null_Statement
2430 and then Comes_From_Source (Stm)
2431 and then No (Next (Stm))
2433 Set_Trivial_Subprogram (Stm);
2435 -- Check for explicit call cases which likely raise an exception
2437 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2438 if Is_Entity_Name (Name (Ostm)) then
2440 Ent : constant Entity_Id := Entity (Name (Ostm));
2443 -- If the procedure is marked No_Return, then likely it
2444 -- raises an exception, but in any case it is not coming
2445 -- back here, so turn on the flag.
2447 if Ekind (Ent) = E_Procedure
2448 and then No_Return (Ent)
2450 Set_Trivial_Subprogram (Stm);
2458 -- Check for variables that are never modified
2464 -- If there is a separate spec, then transfer Never_Set_In_Source
2465 -- flags from out parameters to the corresponding entities in the
2466 -- body. The reason we do that is we want to post error flags on
2467 -- the body entities, not the spec entities.
2469 if Present (Spec_Id) then
2470 E1 := First_Entity (Spec_Id);
2471 while Present (E1) loop
2472 if Ekind (E1) = E_Out_Parameter then
2473 E2 := First_Entity (Body_Id);
2474 while Present (E2) loop
2475 exit when Chars (E1) = Chars (E2);
2479 if Present (E2) then
2480 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2488 -- Check references in body unless it was deleted. Note that the
2489 -- check of Body_Deleted here is not just for efficiency, it is
2490 -- necessary to avoid junk warnings on formal parameters.
2492 if not Body_Deleted then
2493 Check_References (Body_Id);
2496 end Analyze_Subprogram_Body;
2498 ------------------------------------
2499 -- Analyze_Subprogram_Declaration --
2500 ------------------------------------
2502 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2503 Designator : constant Entity_Id :=
2504 Analyze_Subprogram_Specification (Specification (N));
2505 Scop : constant Entity_Id := Current_Scope;
2507 -- Start of processing for Analyze_Subprogram_Declaration
2510 Generate_Definition (Designator);
2512 -- Check for RCI unit subprogram declarations for illegal inlined
2513 -- subprograms and subprograms having access parameter or limited
2514 -- parameter without Read and Write attributes (RM E.2.3(12-13)).
2516 Validate_RCI_Subprogram_Declaration (N);
2520 Defining_Entity (N),
2521 " Analyze subprogram spec: ");
2523 if Debug_Flag_C then
2524 Write_Str ("==== Compiling subprogram spec ");
2525 Write_Name (Chars (Designator));
2526 Write_Str (" from ");
2527 Write_Location (Sloc (N));
2531 New_Overloaded_Entity (Designator);
2532 Check_Delayed_Subprogram (Designator);
2534 -- If the type of the first formal of the current subprogram is a non
2535 -- generic tagged private type , mark the subprogram as being a private
2538 if Present (First_Formal (Designator)) then
2540 Formal_Typ : constant Entity_Id :=
2541 Etype (First_Formal (Designator));
2543 Set_Is_Private_Primitive (Designator,
2544 Is_Tagged_Type (Formal_Typ)
2545 and then Is_Private_Type (Formal_Typ)
2546 and then not Is_Generic_Actual_Type (Formal_Typ));
2550 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
2553 if Ada_Version >= Ada_05
2554 and then Comes_From_Source (N)
2555 and then Is_Dispatching_Operation (Designator)
2562 if Has_Controlling_Result (Designator) then
2563 Etyp := Etype (Designator);
2566 E := First_Entity (Designator);
2568 and then Is_Formal (E)
2569 and then not Is_Controlling_Formal (E)
2577 if Is_Access_Type (Etyp) then
2578 Etyp := Directly_Designated_Type (Etyp);
2581 if Is_Interface (Etyp)
2582 and then not Is_Abstract_Subprogram (Designator)
2583 and then not (Ekind (Designator) = E_Procedure
2584 and then Null_Present (Specification (N)))
2586 Error_Msg_Name_1 := Chars (Defining_Entity (N));
2588 ("(Ada 2005) interface subprogram % must be abstract or null",
2594 -- What is the following code for, it used to be
2596 -- ??? Set_Suppress_Elaboration_Checks
2597 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
2599 -- The following seems equivalent, but a bit dubious
2601 if Elaboration_Checks_Suppressed (Designator) then
2602 Set_Kill_Elaboration_Checks (Designator);
2605 if Scop /= Standard_Standard
2606 and then not Is_Child_Unit (Designator)
2608 Set_Categorization_From_Scope (Designator, Scop);
2610 -- For a compilation unit, check for library-unit pragmas
2612 Push_Scope (Designator);
2613 Set_Categorization_From_Pragmas (N);
2614 Validate_Categorization_Dependency (N, Designator);
2618 -- For a compilation unit, set body required. This flag will only be
2619 -- reset if a valid Import or Interface pragma is processed later on.
2621 if Nkind (Parent (N)) = N_Compilation_Unit then
2622 Set_Body_Required (Parent (N), True);
2624 if Ada_Version >= Ada_05
2625 and then Nkind (Specification (N)) = N_Procedure_Specification
2626 and then Null_Present (Specification (N))
2629 ("null procedure cannot be declared at library level", N);
2633 Generate_Reference_To_Formals (Designator);
2634 Check_Eliminated (Designator);
2636 -- Ada 2005: if procedure is declared with "is null" qualifier,
2637 -- it requires no body.
2639 if Nkind (Specification (N)) = N_Procedure_Specification
2640 and then Null_Present (Specification (N))
2642 Set_Has_Completion (Designator);
2643 Set_Is_Inlined (Designator);
2645 if Is_Protected_Type (Current_Scope) then
2647 ("protected operation cannot be a null procedure", N);
2650 end Analyze_Subprogram_Declaration;
2652 --------------------------------------
2653 -- Analyze_Subprogram_Specification --
2654 --------------------------------------
2656 -- Reminder: N here really is a subprogram specification (not a subprogram
2657 -- declaration). This procedure is called to analyze the specification in
2658 -- both subprogram bodies and subprogram declarations (specs).
2660 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
2661 Designator : constant Entity_Id := Defining_Entity (N);
2662 Formals : constant List_Id := Parameter_Specifications (N);
2664 -- Start of processing for Analyze_Subprogram_Specification
2667 Generate_Definition (Designator);
2669 if Nkind (N) = N_Function_Specification then
2670 Set_Ekind (Designator, E_Function);
2671 Set_Mechanism (Designator, Default_Mechanism);
2674 Set_Ekind (Designator, E_Procedure);
2675 Set_Etype (Designator, Standard_Void_Type);
2678 -- Introduce new scope for analysis of the formals and the return type
2680 Set_Scope (Designator, Current_Scope);
2682 if Present (Formals) then
2683 Push_Scope (Designator);
2684 Process_Formals (Formals, N);
2686 -- Ada 2005 (AI-345): If this is an overriding operation of an
2687 -- inherited interface operation, and the controlling type is
2688 -- a synchronized type, replace the type with its corresponding
2689 -- record, to match the proper signature of an overriding operation.
2691 if Ada_Version >= Ada_05 then
2694 Formal_Typ : Entity_Id;
2695 Rec_Typ : Entity_Id;
2698 Formal := First_Formal (Designator);
2699 while Present (Formal) loop
2700 Formal_Typ := Etype (Formal);
2702 if Is_Concurrent_Type (Formal_Typ)
2703 and then Present (Corresponding_Record_Type (Formal_Typ))
2705 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
2707 if Present (Interfaces (Rec_Typ)) then
2708 Set_Etype (Formal, Rec_Typ);
2712 Next_Formal (Formal);
2719 elsif Nkind (N) = N_Function_Specification then
2720 Analyze_Return_Type (N);
2723 if Nkind (N) = N_Function_Specification then
2724 if Nkind (Designator) = N_Defining_Operator_Symbol then
2725 Valid_Operator_Definition (Designator);
2728 May_Need_Actuals (Designator);
2730 -- Ada 2005 (AI-251): If the return type is abstract, verify that
2731 -- the subprogram is abstract also. This does not apply to renaming
2732 -- declarations, where abstractness is inherited.
2733 -- In case of primitives associated with abstract interface types
2734 -- the check is applied later (see Analyze_Subprogram_Declaration).
2736 if Is_Abstract_Type (Etype (Designator))
2737 and then not Is_Interface (Etype (Designator))
2738 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
2739 and then Nkind (Parent (N)) /=
2740 N_Abstract_Subprogram_Declaration
2742 (Nkind (Parent (N))) /= N_Formal_Abstract_Subprogram_Declaration
2745 ("function that returns abstract type must be abstract", N);
2750 end Analyze_Subprogram_Specification;
2752 --------------------------
2753 -- Build_Body_To_Inline --
2754 --------------------------
2756 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
2757 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
2758 Original_Body : Node_Id;
2759 Body_To_Analyze : Node_Id;
2760 Max_Size : constant := 10;
2761 Stat_Count : Integer := 0;
2763 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
2764 -- Check for declarations that make inlining not worthwhile
2766 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
2767 -- Check for statements that make inlining not worthwhile: any tasking
2768 -- statement, nested at any level. Keep track of total number of
2769 -- elementary statements, as a measure of acceptable size.
2771 function Has_Pending_Instantiation return Boolean;
2772 -- If some enclosing body contains instantiations that appear before the
2773 -- corresponding generic body, the enclosing body has a freeze node so
2774 -- that it can be elaborated after the generic itself. This might
2775 -- conflict with subsequent inlinings, so that it is unsafe to try to
2776 -- inline in such a case.
2778 function Has_Single_Return return Boolean;
2779 -- In general we cannot inline functions that return unconstrained type.
2780 -- However, we can handle such functions if all return statements return
2781 -- a local variable that is the only declaration in the body of the
2782 -- function. In that case the call can be replaced by that local
2783 -- variable as is done for other inlined calls.
2785 procedure Remove_Pragmas;
2786 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
2787 -- parameter has no meaning when the body is inlined and the formals
2788 -- are rewritten. Remove it from body to inline. The analysis of the
2789 -- non-inlined body will handle the pragma properly.
2791 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
2792 -- If the body of the subprogram includes a call that returns an
2793 -- unconstrained type, the secondary stack is involved, and it
2794 -- is not worth inlining.
2796 ------------------------------
2797 -- Has_Excluded_Declaration --
2798 ------------------------------
2800 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
2803 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
2804 -- Nested subprograms make a given body ineligible for inlining, but
2805 -- we make an exception for instantiations of unchecked conversion.
2806 -- The body has not been analyzed yet, so check the name, and verify
2807 -- that the visible entity with that name is the predefined unit.
2809 -----------------------------
2810 -- Is_Unchecked_Conversion --
2811 -----------------------------
2813 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
2814 Id : constant Node_Id := Name (D);
2818 if Nkind (Id) = N_Identifier
2819 and then Chars (Id) = Name_Unchecked_Conversion
2821 Conv := Current_Entity (Id);
2823 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
2824 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
2826 Conv := Current_Entity (Selector_Name (Id));
2831 return Present (Conv)
2832 and then Is_Predefined_File_Name
2833 (Unit_File_Name (Get_Source_Unit (Conv)))
2834 and then Is_Intrinsic_Subprogram (Conv);
2835 end Is_Unchecked_Conversion;
2837 -- Start of processing for Has_Excluded_Declaration
2841 while Present (D) loop
2842 if (Nkind (D) = N_Function_Instantiation
2843 and then not Is_Unchecked_Conversion (D))
2844 or else Nkind_In (D, N_Protected_Type_Declaration,
2845 N_Package_Declaration,
2846 N_Package_Instantiation,
2848 N_Procedure_Instantiation,
2849 N_Task_Type_Declaration)
2852 ("cannot inline & (non-allowed declaration)?", D, Subp);
2860 end Has_Excluded_Declaration;
2862 ----------------------------
2863 -- Has_Excluded_Statement --
2864 ----------------------------
2866 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
2872 while Present (S) loop
2873 Stat_Count := Stat_Count + 1;
2875 if Nkind_In (S, N_Abort_Statement,
2876 N_Asynchronous_Select,
2877 N_Conditional_Entry_Call,
2878 N_Delay_Relative_Statement,
2879 N_Delay_Until_Statement,
2884 ("cannot inline & (non-allowed statement)?", S, Subp);
2887 elsif Nkind (S) = N_Block_Statement then
2888 if Present (Declarations (S))
2889 and then Has_Excluded_Declaration (Declarations (S))
2893 elsif Present (Handled_Statement_Sequence (S))
2896 (Exception_Handlers (Handled_Statement_Sequence (S)))
2898 Has_Excluded_Statement
2899 (Statements (Handled_Statement_Sequence (S))))
2904 elsif Nkind (S) = N_Case_Statement then
2905 E := First (Alternatives (S));
2906 while Present (E) loop
2907 if Has_Excluded_Statement (Statements (E)) then
2914 elsif Nkind (S) = N_If_Statement then
2915 if Has_Excluded_Statement (Then_Statements (S)) then
2919 if Present (Elsif_Parts (S)) then
2920 E := First (Elsif_Parts (S));
2921 while Present (E) loop
2922 if Has_Excluded_Statement (Then_Statements (E)) then
2929 if Present (Else_Statements (S))
2930 and then Has_Excluded_Statement (Else_Statements (S))
2935 elsif Nkind (S) = N_Loop_Statement
2936 and then Has_Excluded_Statement (Statements (S))
2945 end Has_Excluded_Statement;
2947 -------------------------------
2948 -- Has_Pending_Instantiation --
2949 -------------------------------
2951 function Has_Pending_Instantiation return Boolean is
2956 while Present (S) loop
2957 if Is_Compilation_Unit (S)
2958 or else Is_Child_Unit (S)
2961 elsif Ekind (S) = E_Package
2962 and then Has_Forward_Instantiation (S)
2971 end Has_Pending_Instantiation;
2973 ------------------------
2974 -- Has_Single_Return --
2975 ------------------------
2977 function Has_Single_Return return Boolean is
2978 Return_Statement : Node_Id := Empty;
2980 function Check_Return (N : Node_Id) return Traverse_Result;
2986 function Check_Return (N : Node_Id) return Traverse_Result is
2988 if Nkind (N) = N_Simple_Return_Statement then
2989 if Present (Expression (N))
2990 and then Is_Entity_Name (Expression (N))
2992 if No (Return_Statement) then
2993 Return_Statement := N;
2996 elsif Chars (Expression (N)) =
2997 Chars (Expression (Return_Statement))
3006 -- Expression has wrong form
3016 function Check_All_Returns is new Traverse_Func (Check_Return);
3018 -- Start of processing for Has_Single_Return
3021 return Check_All_Returns (N) = OK
3022 and then Present (Declarations (N))
3023 and then Present (First (Declarations (N)))
3024 and then Chars (Expression (Return_Statement)) =
3025 Chars (Defining_Identifier (First (Declarations (N))));
3026 end Has_Single_Return;
3028 --------------------
3029 -- Remove_Pragmas --
3030 --------------------
3032 procedure Remove_Pragmas is
3037 Decl := First (Declarations (Body_To_Analyze));
3038 while Present (Decl) loop
3041 if Nkind (Decl) = N_Pragma
3042 and then (Pragma_Name (Decl) = Name_Unreferenced
3044 Pragma_Name (Decl) = Name_Unmodified)
3053 --------------------------
3054 -- Uses_Secondary_Stack --
3055 --------------------------
3057 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3058 function Check_Call (N : Node_Id) return Traverse_Result;
3059 -- Look for function calls that return an unconstrained type
3065 function Check_Call (N : Node_Id) return Traverse_Result is
3067 if Nkind (N) = N_Function_Call
3068 and then Is_Entity_Name (Name (N))
3069 and then Is_Composite_Type (Etype (Entity (Name (N))))
3070 and then not Is_Constrained (Etype (Entity (Name (N))))
3073 ("cannot inline & (call returns unconstrained type)?",
3081 function Check_Calls is new Traverse_Func (Check_Call);
3084 return Check_Calls (Bod) = Abandon;
3085 end Uses_Secondary_Stack;
3087 -- Start of processing for Build_Body_To_Inline
3090 if Nkind (Decl) = N_Subprogram_Declaration
3091 and then Present (Body_To_Inline (Decl))
3093 return; -- Done already.
3095 -- Functions that return unconstrained composite types require
3096 -- secondary stack handling, and cannot currently be inlined, unless
3097 -- all return statements return a local variable that is the first
3098 -- local declaration in the body.
3100 elsif Ekind (Subp) = E_Function
3101 and then not Is_Scalar_Type (Etype (Subp))
3102 and then not Is_Access_Type (Etype (Subp))
3103 and then not Is_Constrained (Etype (Subp))
3105 if not Has_Single_Return then
3107 ("cannot inline & (unconstrained return type)?", N, Subp);
3111 -- Ditto for functions that return controlled types, where controlled
3112 -- actions interfere in complex ways with inlining.
3114 elsif Ekind (Subp) = E_Function
3115 and then Controlled_Type (Etype (Subp))
3118 ("cannot inline & (controlled return type)?", N, Subp);
3122 if Present (Declarations (N))
3123 and then Has_Excluded_Declaration (Declarations (N))
3128 if Present (Handled_Statement_Sequence (N)) then
3129 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3131 ("cannot inline& (exception handler)?",
3132 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3136 Has_Excluded_Statement
3137 (Statements (Handled_Statement_Sequence (N)))
3143 -- We do not inline a subprogram that is too large, unless it is
3144 -- marked Inline_Always. This pragma does not suppress the other
3145 -- checks on inlining (forbidden declarations, handlers, etc).
3147 if Stat_Count > Max_Size
3148 and then not Has_Pragma_Inline_Always (Subp)
3150 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3154 if Has_Pending_Instantiation then
3156 ("cannot inline& (forward instance within enclosing body)?",
3161 -- Within an instance, the body to inline must be treated as a nested
3162 -- generic, so that the proper global references are preserved.
3164 -- Note that we do not do this at the library level, because it is not
3165 -- needed, and furthermore this causes trouble if front end inlining
3166 -- is activated (-gnatN).
3168 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3169 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3170 Original_Body := Copy_Generic_Node (N, Empty, True);
3172 Original_Body := Copy_Separate_Tree (N);
3175 -- We need to capture references to the formals in order to substitute
3176 -- the actuals at the point of inlining, i.e. instantiation. To treat
3177 -- the formals as globals to the body to inline, we nest it within
3178 -- a dummy parameterless subprogram, declared within the real one.
3179 -- To avoid generating an internal name (which is never public, and
3180 -- which affects serial numbers of other generated names), we use
3181 -- an internal symbol that cannot conflict with user declarations.
3183 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3184 Set_Defining_Unit_Name
3185 (Specification (Original_Body),
3186 Make_Defining_Identifier (Sloc (N), Name_uParent));
3187 Set_Corresponding_Spec (Original_Body, Empty);
3189 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3191 -- Set return type of function, which is also global and does not need
3194 if Ekind (Subp) = E_Function then
3195 Set_Result_Definition (Specification (Body_To_Analyze),
3196 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3199 if No (Declarations (N)) then
3200 Set_Declarations (N, New_List (Body_To_Analyze));
3202 Append (Body_To_Analyze, Declarations (N));
3205 Expander_Mode_Save_And_Set (False);
3208 Analyze (Body_To_Analyze);
3209 Push_Scope (Defining_Entity (Body_To_Analyze));
3210 Save_Global_References (Original_Body);
3212 Remove (Body_To_Analyze);
3214 Expander_Mode_Restore;
3216 -- Restore environment if previously saved
3218 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3222 -- If secondary stk used there is no point in inlining. We have
3223 -- already issued the warning in this case, so nothing to do.
3225 if Uses_Secondary_Stack (Body_To_Analyze) then
3229 Set_Body_To_Inline (Decl, Original_Body);
3230 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3231 Set_Is_Inlined (Subp);
3232 end Build_Body_To_Inline;
3238 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3240 -- Do not emit warning if this is a predefined unit which is not
3241 -- the main unit. With validity checks enabled, some predefined
3242 -- subprograms may contain nested subprograms and become ineligible
3245 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3246 and then not In_Extended_Main_Source_Unit (Subp)
3250 elsif Has_Pragma_Inline_Always (Subp) then
3252 -- Remove last character (question mark) to make this into an error,
3253 -- because the Inline_Always pragma cannot be obeyed.
3255 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3257 elsif Ineffective_Inline_Warnings then
3258 Error_Msg_NE (Msg, N, Subp);
3262 -----------------------
3263 -- Check_Conformance --
3264 -----------------------
3266 procedure Check_Conformance
3267 (New_Id : Entity_Id;
3269 Ctype : Conformance_Type;
3271 Conforms : out Boolean;
3272 Err_Loc : Node_Id := Empty;
3273 Get_Inst : Boolean := False;
3274 Skip_Controlling_Formals : Boolean := False)
3276 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3277 -- Post error message for conformance error on given node. Two messages
3278 -- are output. The first points to the previous declaration with a
3279 -- general "no conformance" message. The second is the detailed reason,
3280 -- supplied as Msg. The parameter N provide information for a possible
3281 -- & insertion in the message, and also provides the location for
3282 -- posting the message in the absence of a specified Err_Loc location.
3284 -----------------------
3285 -- Conformance_Error --
3286 -----------------------
3288 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3295 if No (Err_Loc) then
3301 Error_Msg_Sloc := Sloc (Old_Id);
3304 when Type_Conformant =>
3306 ("not type conformant with declaration#!", Enode);
3308 when Mode_Conformant =>
3309 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3311 ("not mode conformant with operation inherited#!",
3315 ("not mode conformant with declaration#!", Enode);
3318 when Subtype_Conformant =>
3319 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3321 ("not subtype conformant with operation inherited#!",
3325 ("not subtype conformant with declaration#!", Enode);
3328 when Fully_Conformant =>
3329 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3331 ("not fully conformant with operation inherited#!",
3335 ("not fully conformant with declaration#!", Enode);
3339 Error_Msg_NE (Msg, Enode, N);
3341 end Conformance_Error;
3345 Old_Type : constant Entity_Id := Etype (Old_Id);
3346 New_Type : constant Entity_Id := Etype (New_Id);
3347 Old_Formal : Entity_Id;
3348 New_Formal : Entity_Id;
3349 Access_Types_Match : Boolean;
3350 Old_Formal_Base : Entity_Id;
3351 New_Formal_Base : Entity_Id;
3353 -- Start of processing for Check_Conformance
3358 -- We need a special case for operators, since they don't appear
3361 if Ctype = Type_Conformant then
3362 if Ekind (New_Id) = E_Operator
3363 and then Operator_Matches_Spec (New_Id, Old_Id)
3369 -- If both are functions/operators, check return types conform
3371 if Old_Type /= Standard_Void_Type
3372 and then New_Type /= Standard_Void_Type
3375 -- If we are checking interface conformance we omit controlling
3376 -- arguments and result, because we are only checking the conformance
3377 -- of the remaining parameters.
3379 if Has_Controlling_Result (Old_Id)
3380 and then Has_Controlling_Result (New_Id)
3381 and then Skip_Controlling_Formals
3385 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3386 Conformance_Error ("\return type does not match!", New_Id);
3390 -- Ada 2005 (AI-231): In case of anonymous access types check the
3391 -- null-exclusion and access-to-constant attributes match.
3393 if Ada_Version >= Ada_05
3394 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3396 (Can_Never_Be_Null (Old_Type)
3397 /= Can_Never_Be_Null (New_Type)
3398 or else Is_Access_Constant (Etype (Old_Type))
3399 /= Is_Access_Constant (Etype (New_Type)))
3401 Conformance_Error ("\return type does not match!", New_Id);
3405 -- If either is a function/operator and the other isn't, error
3407 elsif Old_Type /= Standard_Void_Type
3408 or else New_Type /= Standard_Void_Type
3410 Conformance_Error ("\functions can only match functions!", New_Id);
3414 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
3415 -- If this is a renaming as body, refine error message to indicate that
3416 -- the conflict is with the original declaration. If the entity is not
3417 -- frozen, the conventions don't have to match, the one of the renamed
3418 -- entity is inherited.
3420 if Ctype >= Subtype_Conformant then
3421 if Convention (Old_Id) /= Convention (New_Id) then
3423 if not Is_Frozen (New_Id) then
3426 elsif Present (Err_Loc)
3427 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
3428 and then Present (Corresponding_Spec (Err_Loc))
3430 Error_Msg_Name_1 := Chars (New_Id);
3432 Name_Ada + Convention_Id'Pos (Convention (New_Id));
3434 Conformance_Error ("\prior declaration for% has convention %!");
3437 Conformance_Error ("\calling conventions do not match!");
3442 elsif Is_Formal_Subprogram (Old_Id)
3443 or else Is_Formal_Subprogram (New_Id)
3445 Conformance_Error ("\formal subprograms not allowed!");
3450 -- Deal with parameters
3452 -- Note: we use the entity information, rather than going directly
3453 -- to the specification in the tree. This is not only simpler, but
3454 -- absolutely necessary for some cases of conformance tests between
3455 -- operators, where the declaration tree simply does not exist!
3457 Old_Formal := First_Formal (Old_Id);
3458 New_Formal := First_Formal (New_Id);
3460 while Present (Old_Formal) and then Present (New_Formal) loop
3461 if Is_Controlling_Formal (Old_Formal)
3462 and then Is_Controlling_Formal (New_Formal)
3463 and then Skip_Controlling_Formals
3465 goto Skip_Controlling_Formal;
3468 if Ctype = Fully_Conformant then
3470 -- Names must match. Error message is more accurate if we do
3471 -- this before checking that the types of the formals match.
3473 if Chars (Old_Formal) /= Chars (New_Formal) then
3474 Conformance_Error ("\name & does not match!", New_Formal);
3476 -- Set error posted flag on new formal as well to stop
3477 -- junk cascaded messages in some cases.
3479 Set_Error_Posted (New_Formal);
3484 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
3485 -- case occurs whenever a subprogram is being renamed and one of its
3486 -- parameters imposes a null exclusion. For example:
3488 -- type T is null record;
3489 -- type Acc_T is access T;
3490 -- subtype Acc_T_Sub is Acc_T;
3492 -- procedure P (Obj : not null Acc_T_Sub); -- itype
3493 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
3496 Old_Formal_Base := Etype (Old_Formal);
3497 New_Formal_Base := Etype (New_Formal);
3500 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
3501 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
3504 Access_Types_Match := Ada_Version >= Ada_05
3506 -- Ensure that this rule is only applied when New_Id is a
3507 -- renaming of Old_Id.
3509 and then Nkind (Parent (Parent (New_Id))) =
3510 N_Subprogram_Renaming_Declaration
3511 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
3512 and then Present (Entity (Name (Parent (Parent (New_Id)))))
3513 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
3515 -- Now handle the allowed access-type case
3517 and then Is_Access_Type (Old_Formal_Base)
3518 and then Is_Access_Type (New_Formal_Base)
3520 -- The type kinds must match. The only exception occurs with
3521 -- multiple generics of the form:
3524 -- type F is private; type A is private;
3525 -- type F_Ptr is access F; type A_Ptr is access A;
3526 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
3527 -- package F_Pack is ... package A_Pack is
3528 -- package F_Inst is
3529 -- new F_Pack (A, A_Ptr, A_P);
3531 -- When checking for conformance between the parameters of A_P
3532 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
3533 -- because the compiler has transformed A_Ptr into a subtype of
3534 -- F_Ptr. We catch this case in the code below.
3536 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
3538 (Is_Generic_Type (Old_Formal_Base)
3539 and then Is_Generic_Type (New_Formal_Base)
3540 and then Is_Internal (New_Formal_Base)
3541 and then Etype (Etype (New_Formal_Base)) =
3543 and then Directly_Designated_Type (Old_Formal_Base) =
3544 Directly_Designated_Type (New_Formal_Base)
3545 and then ((Is_Itype (Old_Formal_Base)
3546 and then Can_Never_Be_Null (Old_Formal_Base))
3548 (Is_Itype (New_Formal_Base)
3549 and then Can_Never_Be_Null (New_Formal_Base)));
3551 -- Types must always match. In the visible part of an instance,
3552 -- usual overloading rules for dispatching operations apply, and
3553 -- we check base types (not the actual subtypes).
3555 if In_Instance_Visible_Part
3556 and then Is_Dispatching_Operation (New_Id)
3558 if not Conforming_Types
3559 (T1 => Base_Type (Etype (Old_Formal)),
3560 T2 => Base_Type (Etype (New_Formal)),
3562 Get_Inst => Get_Inst)
3563 and then not Access_Types_Match
3565 Conformance_Error ("\type of & does not match!", New_Formal);
3569 elsif not Conforming_Types
3570 (T1 => Old_Formal_Base,
3571 T2 => New_Formal_Base,
3573 Get_Inst => Get_Inst)
3574 and then not Access_Types_Match
3576 Conformance_Error ("\type of & does not match!", New_Formal);
3580 -- For mode conformance, mode must match
3582 if Ctype >= Mode_Conformant then
3583 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
3584 Conformance_Error ("\mode of & does not match!", New_Formal);
3587 -- Part of mode conformance for access types is having the same
3588 -- constant modifier.
3590 elsif Access_Types_Match
3591 and then Is_Access_Constant (Old_Formal_Base) /=
3592 Is_Access_Constant (New_Formal_Base)
3595 ("\constant modifier does not match!", New_Formal);
3600 if Ctype >= Subtype_Conformant then
3602 -- Ada 2005 (AI-231): In case of anonymous access types check
3603 -- the null-exclusion and access-to-constant attributes must
3606 if Ada_Version >= Ada_05
3607 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
3608 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
3610 (Can_Never_Be_Null (Old_Formal) /=
3611 Can_Never_Be_Null (New_Formal)
3613 Is_Access_Constant (Etype (Old_Formal)) /=
3614 Is_Access_Constant (Etype (New_Formal)))
3616 -- It is allowed to omit the null-exclusion in case of stream
3617 -- attribute subprograms. We recognize stream subprograms
3618 -- through their TSS-generated suffix.
3621 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
3623 if TSS_Name /= TSS_Stream_Read
3624 and then TSS_Name /= TSS_Stream_Write
3625 and then TSS_Name /= TSS_Stream_Input
3626 and then TSS_Name /= TSS_Stream_Output
3629 ("\type of & does not match!", New_Formal);
3636 -- Full conformance checks
3638 if Ctype = Fully_Conformant then
3640 -- We have checked already that names match
3642 if Parameter_Mode (Old_Formal) = E_In_Parameter then
3644 -- Check default expressions for in parameters
3647 NewD : constant Boolean :=
3648 Present (Default_Value (New_Formal));
3649 OldD : constant Boolean :=
3650 Present (Default_Value (Old_Formal));
3652 if NewD or OldD then
3654 -- The old default value has been analyzed because the
3655 -- current full declaration will have frozen everything
3656 -- before. The new default value has not been analyzed,
3657 -- so analyze it now before we check for conformance.
3660 Push_Scope (New_Id);
3661 Preanalyze_Spec_Expression
3662 (Default_Value (New_Formal), Etype (New_Formal));
3666 if not (NewD and OldD)
3667 or else not Fully_Conformant_Expressions
3668 (Default_Value (Old_Formal),
3669 Default_Value (New_Formal))
3672 ("\default expression for & does not match!",
3681 -- A couple of special checks for Ada 83 mode. These checks are
3682 -- skipped if either entity is an operator in package Standard,
3683 -- or if either old or new instance is not from the source program.
3685 if Ada_Version = Ada_83
3686 and then Sloc (Old_Id) > Standard_Location
3687 and then Sloc (New_Id) > Standard_Location
3688 and then Comes_From_Source (Old_Id)
3689 and then Comes_From_Source (New_Id)
3692 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
3693 New_Param : constant Node_Id := Declaration_Node (New_Formal);
3696 -- Explicit IN must be present or absent in both cases. This
3697 -- test is required only in the full conformance case.
3699 if In_Present (Old_Param) /= In_Present (New_Param)
3700 and then Ctype = Fully_Conformant
3703 ("\(Ada 83) IN must appear in both declarations",
3708 -- Grouping (use of comma in param lists) must be the same
3709 -- This is where we catch a misconformance like:
3712 -- A : Integer; B : Integer
3714 -- which are represented identically in the tree except
3715 -- for the setting of the flags More_Ids and Prev_Ids.
3717 if More_Ids (Old_Param) /= More_Ids (New_Param)
3718 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
3721 ("\grouping of & does not match!", New_Formal);
3727 -- This label is required when skipping controlling formals
3729 <<Skip_Controlling_Formal>>
3731 Next_Formal (Old_Formal);
3732 Next_Formal (New_Formal);
3735 if Present (Old_Formal) then
3736 Conformance_Error ("\too few parameters!");
3739 elsif Present (New_Formal) then
3740 Conformance_Error ("\too many parameters!", New_Formal);
3743 end Check_Conformance;
3745 -----------------------
3746 -- Check_Conventions --
3747 -----------------------
3749 procedure Check_Conventions (Typ : Entity_Id) is
3750 Ifaces_List : Elist_Id;
3752 procedure Check_Convention (Op : Entity_Id);
3753 -- Verify that the convention of inherited dispatching operation Op is
3754 -- consistent among all subprograms it overrides. In order to minimize
3755 -- the search, Search_From is utilized to designate a specific point in
3756 -- the list rather than iterating over the whole list once more.
3758 ----------------------
3759 -- Check_Convention --
3760 ----------------------
3762 procedure Check_Convention (Op : Entity_Id) is
3763 Iface_Elmt : Elmt_Id;
3764 Iface_Prim_Elmt : Elmt_Id;
3765 Iface_Prim : Entity_Id;
3768 Iface_Elmt := First_Elmt (Ifaces_List);
3769 while Present (Iface_Elmt) loop
3771 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
3772 while Present (Iface_Prim_Elmt) loop
3773 Iface_Prim := Node (Iface_Prim_Elmt);
3775 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
3776 and then Convention (Iface_Prim) /= Convention (Op)
3779 ("inconsistent conventions in primitive operations", Typ);
3781 Error_Msg_Name_1 := Chars (Op);
3782 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
3783 Error_Msg_Sloc := Sloc (Op);
3785 if Comes_From_Source (Op) then
3786 if not Is_Overriding_Operation (Op) then
3787 Error_Msg_N ("\\primitive % defined #", Typ);
3789 Error_Msg_N ("\\overriding operation % with " &
3790 "convention % defined #", Typ);
3793 else pragma Assert (Present (Alias (Op)));
3794 Error_Msg_Sloc := Sloc (Alias (Op));
3795 Error_Msg_N ("\\inherited operation % with " &
3796 "convention % defined #", Typ);
3799 Error_Msg_Name_1 := Chars (Op);
3801 Get_Convention_Name (Convention (Iface_Prim));
3802 Error_Msg_Sloc := Sloc (Iface_Prim);
3803 Error_Msg_N ("\\overridden operation % with " &
3804 "convention % defined #", Typ);
3806 -- Avoid cascading errors
3811 Next_Elmt (Iface_Prim_Elmt);
3814 Next_Elmt (Iface_Elmt);
3816 end Check_Convention;
3820 Prim_Op : Entity_Id;
3821 Prim_Op_Elmt : Elmt_Id;
3823 -- Start of processing for Check_Conventions
3826 if not Has_Interfaces (Typ) then
3830 Collect_Interfaces (Typ, Ifaces_List);
3832 -- The algorithm checks every overriding dispatching operation against
3833 -- all the corresponding overridden dispatching operations, detecting
3834 -- differences in conventions.
3836 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
3837 while Present (Prim_Op_Elmt) loop
3838 Prim_Op := Node (Prim_Op_Elmt);
3840 -- A small optimization: skip the predefined dispatching operations
3841 -- since they always have the same convention.
3843 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
3844 Check_Convention (Prim_Op);
3847 Next_Elmt (Prim_Op_Elmt);
3849 end Check_Conventions;
3851 ------------------------------
3852 -- Check_Delayed_Subprogram --
3853 ------------------------------
3855 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
3858 procedure Possible_Freeze (T : Entity_Id);
3859 -- T is the type of either a formal parameter or of the return type.
3860 -- If T is not yet frozen and needs a delayed freeze, then the
3861 -- subprogram itself must be delayed.
3863 ---------------------
3864 -- Possible_Freeze --
3865 ---------------------
3867 procedure Possible_Freeze (T : Entity_Id) is
3869 if Has_Delayed_Freeze (T)
3870 and then not Is_Frozen (T)
3872 Set_Has_Delayed_Freeze (Designator);
3874 elsif Is_Access_Type (T)
3875 and then Has_Delayed_Freeze (Designated_Type (T))
3876 and then not Is_Frozen (Designated_Type (T))
3878 Set_Has_Delayed_Freeze (Designator);
3880 end Possible_Freeze;
3882 -- Start of processing for Check_Delayed_Subprogram
3885 -- Never need to freeze abstract subprogram
3887 if Ekind (Designator) /= E_Subprogram_Type
3888 and then Is_Abstract_Subprogram (Designator)
3892 -- Need delayed freeze if return type itself needs a delayed
3893 -- freeze and is not yet frozen.
3895 Possible_Freeze (Etype (Designator));
3896 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
3898 -- Need delayed freeze if any of the formal types themselves need
3899 -- a delayed freeze and are not yet frozen.
3901 F := First_Formal (Designator);
3902 while Present (F) loop
3903 Possible_Freeze (Etype (F));
3904 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
3909 -- Mark functions that return by reference. Note that it cannot be
3910 -- done for delayed_freeze subprograms because the underlying
3911 -- returned type may not be known yet (for private types)
3913 if not Has_Delayed_Freeze (Designator)
3914 and then Expander_Active
3917 Typ : constant Entity_Id := Etype (Designator);
3918 Utyp : constant Entity_Id := Underlying_Type (Typ);
3921 if Is_Inherently_Limited_Type (Typ) then
3922 Set_Returns_By_Ref (Designator);
3924 elsif Present (Utyp) and then CW_Or_Controlled_Type (Utyp) then
3925 Set_Returns_By_Ref (Designator);
3929 end Check_Delayed_Subprogram;
3931 ------------------------------------
3932 -- Check_Discriminant_Conformance --
3933 ------------------------------------
3935 procedure Check_Discriminant_Conformance
3940 Old_Discr : Entity_Id := First_Discriminant (Prev);
3941 New_Discr : Node_Id := First (Discriminant_Specifications (N));
3942 New_Discr_Id : Entity_Id;
3943 New_Discr_Type : Entity_Id;
3945 procedure Conformance_Error (Msg : String; N : Node_Id);
3946 -- Post error message for conformance error on given node. Two messages
3947 -- are output. The first points to the previous declaration with a
3948 -- general "no conformance" message. The second is the detailed reason,
3949 -- supplied as Msg. The parameter N provide information for a possible
3950 -- & insertion in the message.
3952 -----------------------
3953 -- Conformance_Error --
3954 -----------------------
3956 procedure Conformance_Error (Msg : String; N : Node_Id) is
3958 Error_Msg_Sloc := Sloc (Prev_Loc);
3959 Error_Msg_N ("not fully conformant with declaration#!", N);
3960 Error_Msg_NE (Msg, N, N);
3961 end Conformance_Error;
3963 -- Start of processing for Check_Discriminant_Conformance
3966 while Present (Old_Discr) and then Present (New_Discr) loop
3968 New_Discr_Id := Defining_Identifier (New_Discr);
3970 -- The subtype mark of the discriminant on the full type has not
3971 -- been analyzed so we do it here. For an access discriminant a new
3974 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
3976 Access_Definition (N, Discriminant_Type (New_Discr));
3979 Analyze (Discriminant_Type (New_Discr));
3980 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
3983 if not Conforming_Types
3984 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
3986 Conformance_Error ("type of & does not match!", New_Discr_Id);
3989 -- Treat the new discriminant as an occurrence of the old one,
3990 -- for navigation purposes, and fill in some semantic
3991 -- information, for completeness.
3993 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
3994 Set_Etype (New_Discr_Id, Etype (Old_Discr));
3995 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4000 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4001 Conformance_Error ("name & does not match!", New_Discr_Id);
4005 -- Default expressions must match
4008 NewD : constant Boolean :=
4009 Present (Expression (New_Discr));
4010 OldD : constant Boolean :=
4011 Present (Expression (Parent (Old_Discr)));
4014 if NewD or OldD then
4016 -- The old default value has been analyzed and expanded,
4017 -- because the current full declaration will have frozen
4018 -- everything before. The new default values have not been
4019 -- expanded, so expand now to check conformance.
4022 Preanalyze_Spec_Expression
4023 (Expression (New_Discr), New_Discr_Type);
4026 if not (NewD and OldD)
4027 or else not Fully_Conformant_Expressions
4028 (Expression (Parent (Old_Discr)),
4029 Expression (New_Discr))
4033 ("default expression for & does not match!",
4040 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4042 if Ada_Version = Ada_83 then
4044 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4047 -- Grouping (use of comma in param lists) must be the same
4048 -- This is where we catch a misconformance like:
4051 -- A : Integer; B : Integer
4053 -- which are represented identically in the tree except
4054 -- for the setting of the flags More_Ids and Prev_Ids.
4056 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4057 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4060 ("grouping of & does not match!", New_Discr_Id);
4066 Next_Discriminant (Old_Discr);
4070 if Present (Old_Discr) then
4071 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4074 elsif Present (New_Discr) then
4076 ("too many discriminants!", Defining_Identifier (New_Discr));
4079 end Check_Discriminant_Conformance;
4081 ----------------------------
4082 -- Check_Fully_Conformant --
4083 ----------------------------
4085 procedure Check_Fully_Conformant
4086 (New_Id : Entity_Id;
4088 Err_Loc : Node_Id := Empty)
4091 pragma Warnings (Off, Result);
4094 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4095 end Check_Fully_Conformant;
4097 ---------------------------
4098 -- Check_Mode_Conformant --
4099 ---------------------------
4101 procedure Check_Mode_Conformant
4102 (New_Id : Entity_Id;
4104 Err_Loc : Node_Id := Empty;
4105 Get_Inst : Boolean := False)
4108 pragma Warnings (Off, Result);
4111 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4112 end Check_Mode_Conformant;
4114 --------------------------------
4115 -- Check_Overriding_Indicator --
4116 --------------------------------
4118 procedure Check_Overriding_Indicator
4120 Overridden_Subp : Entity_Id;
4121 Is_Primitive : Boolean)
4127 -- No overriding indicator for literals
4129 if Ekind (Subp) = E_Enumeration_Literal then
4132 elsif Ekind (Subp) = E_Entry then
4133 Decl := Parent (Subp);
4136 Decl := Unit_Declaration_Node (Subp);
4139 if Nkind_In (Decl, N_Subprogram_Body,
4140 N_Subprogram_Body_Stub,
4141 N_Subprogram_Declaration,
4142 N_Abstract_Subprogram_Declaration,
4143 N_Subprogram_Renaming_Declaration)
4145 Spec := Specification (Decl);
4147 elsif Nkind (Decl) = N_Entry_Declaration then
4154 if Present (Overridden_Subp) then
4155 if Must_Not_Override (Spec) then
4156 Error_Msg_Sloc := Sloc (Overridden_Subp);
4158 if Ekind (Subp) = E_Entry then
4160 ("entry & overrides inherited operation #", Spec, Subp);
4163 ("subprogram & overrides inherited operation #", Spec, Subp);
4166 elsif Is_Subprogram (Subp) then
4167 Set_Is_Overriding_Operation (Subp);
4170 -- If Subp is an operator, it may override a predefined operation.
4171 -- In that case overridden_subp is empty because of our implicit
4172 -- representation for predefined operators. We have to check whether the
4173 -- signature of Subp matches that of a predefined operator. Note that
4174 -- first argument provides the name of the operator, and the second
4175 -- argument the signature that may match that of a standard operation.
4176 -- If the indicator is overriding, then the operator must match a
4177 -- predefined signature, because we know already that there is no
4178 -- explicit overridden operation.
4180 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
4182 if Must_Not_Override (Spec) then
4183 if not Is_Primitive then
4185 ("overriding indicator only allowed "
4186 & "if subprogram is primitive", Subp);
4188 elsif Operator_Matches_Spec (Subp, Subp) then
4190 ("subprogram & overrides predefined operator ", Spec, Subp);
4193 elsif Is_Overriding_Operation (Subp) then
4196 elsif Must_Override (Spec) then
4197 if not Operator_Matches_Spec (Subp, Subp) then
4198 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
4201 Set_Is_Overriding_Operation (Subp);
4205 elsif Must_Override (Spec) then
4206 if Ekind (Subp) = E_Entry then
4207 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
4209 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
4212 -- If the operation is marked "not overriding" and it's not primitive
4213 -- then an error is issued, unless this is an operation of a task or
4214 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
4215 -- has been specified have already been checked above.
4217 elsif Must_Not_Override (Spec)
4218 and then not Is_Primitive
4219 and then Ekind (Subp) /= E_Entry
4220 and then Ekind (Scope (Subp)) /= E_Protected_Type
4223 ("overriding indicator only allowed if subprogram is primitive",
4227 end Check_Overriding_Indicator;
4233 -- Note: this procedure needs to know far too much about how the expander
4234 -- messes with exceptions. The use of the flag Exception_Junk and the
4235 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
4236 -- works, but is not very clean. It would be better if the expansion
4237 -- routines would leave Original_Node working nicely, and we could use
4238 -- Original_Node here to ignore all the peculiar expander messing ???
4240 procedure Check_Returns
4244 Proc : Entity_Id := Empty)
4248 procedure Check_Statement_Sequence (L : List_Id);
4249 -- Internal recursive procedure to check a list of statements for proper
4250 -- termination by a return statement (or a transfer of control or a
4251 -- compound statement that is itself internally properly terminated).
4253 ------------------------------
4254 -- Check_Statement_Sequence --
4255 ------------------------------
4257 procedure Check_Statement_Sequence (L : List_Id) is
4262 Raise_Exception_Call : Boolean;
4263 -- Set True if statement sequence terminated by Raise_Exception call
4264 -- or a Reraise_Occurrence call.
4267 Raise_Exception_Call := False;
4269 -- Get last real statement
4271 Last_Stm := Last (L);
4273 -- Deal with digging out exception handler statement sequences that
4274 -- have been transformed by the local raise to goto optimization.
4275 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
4276 -- optimization has occurred, we are looking at something like:
4279 -- original stmts in block
4283 -- goto L1; | omitted if No_Exception_Propagation
4288 -- goto L3; -- skip handler when exception not raised
4290 -- <<L1>> -- target label for local exception
4304 -- and what we have to do is to dig out the estmts1 and estmts2
4305 -- sequences (which were the original sequences of statements in
4306 -- the exception handlers) and check them.
4308 if Nkind (Last_Stm) = N_Label
4309 and then Exception_Junk (Last_Stm)
4315 exit when Nkind (Stm) /= N_Block_Statement;
4316 exit when not Exception_Junk (Stm);
4319 exit when Nkind (Stm) /= N_Label;
4320 exit when not Exception_Junk (Stm);
4321 Check_Statement_Sequence
4322 (Statements (Handled_Statement_Sequence (Next (Stm))));
4327 exit when Nkind (Stm) /= N_Goto_Statement;
4328 exit when not Exception_Junk (Stm);
4332 -- Don't count pragmas
4334 while Nkind (Last_Stm) = N_Pragma
4336 -- Don't count call to SS_Release (can happen after Raise_Exception)
4339 (Nkind (Last_Stm) = N_Procedure_Call_Statement
4341 Nkind (Name (Last_Stm)) = N_Identifier
4343 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
4345 -- Don't count exception junk
4348 (Nkind_In (Last_Stm, N_Goto_Statement,
4350 N_Object_Declaration)
4351 and then Exception_Junk (Last_Stm))
4352 or else Nkind (Last_Stm) in N_Push_xxx_Label
4353 or else Nkind (Last_Stm) in N_Pop_xxx_Label
4358 -- Here we have the "real" last statement
4360 Kind := Nkind (Last_Stm);
4362 -- Transfer of control, OK. Note that in the No_Return procedure
4363 -- case, we already diagnosed any explicit return statements, so
4364 -- we can treat them as OK in this context.
4366 if Is_Transfer (Last_Stm) then
4369 -- Check cases of explicit non-indirect procedure calls
4371 elsif Kind = N_Procedure_Call_Statement
4372 and then Is_Entity_Name (Name (Last_Stm))
4374 -- Check call to Raise_Exception procedure which is treated
4375 -- specially, as is a call to Reraise_Occurrence.
4377 -- We suppress the warning in these cases since it is likely that
4378 -- the programmer really does not expect to deal with the case
4379 -- of Null_Occurrence, and thus would find a warning about a
4380 -- missing return curious, and raising Program_Error does not
4381 -- seem such a bad behavior if this does occur.
4383 -- Note that in the Ada 2005 case for Raise_Exception, the actual
4384 -- behavior will be to raise Constraint_Error (see AI-329).
4386 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
4388 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
4390 Raise_Exception_Call := True;
4392 -- For Raise_Exception call, test first argument, if it is
4393 -- an attribute reference for a 'Identity call, then we know
4394 -- that the call cannot possibly return.
4397 Arg : constant Node_Id :=
4398 Original_Node (First_Actual (Last_Stm));
4400 if Nkind (Arg) = N_Attribute_Reference
4401 and then Attribute_Name (Arg) = Name_Identity
4408 -- If statement, need to look inside if there is an else and check
4409 -- each constituent statement sequence for proper termination.
4411 elsif Kind = N_If_Statement
4412 and then Present (Else_Statements (Last_Stm))
4414 Check_Statement_Sequence (Then_Statements (Last_Stm));
4415 Check_Statement_Sequence (Else_Statements (Last_Stm));
4417 if Present (Elsif_Parts (Last_Stm)) then
4419 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
4422 while Present (Elsif_Part) loop
4423 Check_Statement_Sequence (Then_Statements (Elsif_Part));
4431 -- Case statement, check each case for proper termination
4433 elsif Kind = N_Case_Statement then
4437 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
4438 while Present (Case_Alt) loop
4439 Check_Statement_Sequence (Statements (Case_Alt));
4440 Next_Non_Pragma (Case_Alt);
4446 -- Block statement, check its handled sequence of statements
4448 elsif Kind = N_Block_Statement then
4454 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
4463 -- Loop statement. If there is an iteration scheme, we can definitely
4464 -- fall out of the loop. Similarly if there is an exit statement, we
4465 -- can fall out. In either case we need a following return.
4467 elsif Kind = N_Loop_Statement then
4468 if Present (Iteration_Scheme (Last_Stm))
4469 or else Has_Exit (Entity (Identifier (Last_Stm)))
4473 -- A loop with no exit statement or iteration scheme is either
4474 -- an infinite loop, or it has some other exit (raise/return).
4475 -- In either case, no warning is required.
4481 -- Timed entry call, check entry call and delay alternatives
4483 -- Note: in expanded code, the timed entry call has been converted
4484 -- to a set of expanded statements on which the check will work
4485 -- correctly in any case.
4487 elsif Kind = N_Timed_Entry_Call then
4489 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4490 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
4493 -- If statement sequence of entry call alternative is missing,
4494 -- then we can definitely fall through, and we post the error
4495 -- message on the entry call alternative itself.
4497 if No (Statements (ECA)) then
4500 -- If statement sequence of delay alternative is missing, then
4501 -- we can definitely fall through, and we post the error
4502 -- message on the delay alternative itself.
4504 -- Note: if both ECA and DCA are missing the return, then we
4505 -- post only one message, should be enough to fix the bugs.
4506 -- If not we will get a message next time on the DCA when the
4509 elsif No (Statements (DCA)) then
4512 -- Else check both statement sequences
4515 Check_Statement_Sequence (Statements (ECA));
4516 Check_Statement_Sequence (Statements (DCA));
4521 -- Conditional entry call, check entry call and else part
4523 -- Note: in expanded code, the conditional entry call has been
4524 -- converted to a set of expanded statements on which the check
4525 -- will work correctly in any case.
4527 elsif Kind = N_Conditional_Entry_Call then
4529 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4532 -- If statement sequence of entry call alternative is missing,
4533 -- then we can definitely fall through, and we post the error
4534 -- message on the entry call alternative itself.
4536 if No (Statements (ECA)) then
4539 -- Else check statement sequence and else part
4542 Check_Statement_Sequence (Statements (ECA));
4543 Check_Statement_Sequence (Else_Statements (Last_Stm));
4549 -- If we fall through, issue appropriate message
4552 if not Raise_Exception_Call then
4554 ("?RETURN statement missing following this statement!",
4557 ("\?Program_Error may be raised at run time!",
4561 -- Note: we set Err even though we have not issued a warning
4562 -- because we still have a case of a missing return. This is
4563 -- an extremely marginal case, probably will never be noticed
4564 -- but we might as well get it right.
4568 -- Otherwise we have the case of a procedure marked No_Return
4571 if not Raise_Exception_Call then
4573 ("?implied return after this statement " &
4574 "will raise Program_Error",
4577 ("\?procedure & is marked as No_Return!",
4582 RE : constant Node_Id :=
4583 Make_Raise_Program_Error (Sloc (Last_Stm),
4584 Reason => PE_Implicit_Return);
4586 Insert_After (Last_Stm, RE);
4590 end Check_Statement_Sequence;
4592 -- Start of processing for Check_Returns
4596 Check_Statement_Sequence (Statements (HSS));
4598 if Present (Exception_Handlers (HSS)) then
4599 Handler := First_Non_Pragma (Exception_Handlers (HSS));
4600 while Present (Handler) loop
4601 Check_Statement_Sequence (Statements (Handler));
4602 Next_Non_Pragma (Handler);
4607 ----------------------------
4608 -- Check_Subprogram_Order --
4609 ----------------------------
4611 procedure Check_Subprogram_Order (N : Node_Id) is
4613 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
4614 -- This is used to check if S1 > S2 in the sense required by this
4615 -- test, for example nameab < namec, but name2 < name10.
4617 -----------------------------
4618 -- Subprogram_Name_Greater --
4619 -----------------------------
4621 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
4626 -- Remove trailing numeric parts
4629 while S1 (L1) in '0' .. '9' loop
4634 while S2 (L2) in '0' .. '9' loop
4638 -- If non-numeric parts non-equal, that's decisive
4640 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
4643 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
4646 -- If non-numeric parts equal, compare suffixed numeric parts. Note
4647 -- that a missing suffix is treated as numeric zero in this test.
4651 while L1 < S1'Last loop
4653 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
4657 while L2 < S2'Last loop
4659 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
4664 end Subprogram_Name_Greater;
4666 -- Start of processing for Check_Subprogram_Order
4669 -- Check body in alpha order if this is option
4672 and then Style_Check_Order_Subprograms
4673 and then Nkind (N) = N_Subprogram_Body
4674 and then Comes_From_Source (N)
4675 and then In_Extended_Main_Source_Unit (N)
4679 renames Scope_Stack.Table
4680 (Scope_Stack.Last).Last_Subprogram_Name;
4682 Body_Id : constant Entity_Id :=
4683 Defining_Entity (Specification (N));
4686 Get_Decoded_Name_String (Chars (Body_Id));
4689 if Subprogram_Name_Greater
4690 (LSN.all, Name_Buffer (1 .. Name_Len))
4692 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
4698 LSN := new String'(Name_Buffer (1 .. Name_Len));
4701 end Check_Subprogram_Order;
4703 ------------------------------
4704 -- Check_Subtype_Conformant --
4705 ------------------------------
4707 procedure Check_Subtype_Conformant
4708 (New_Id : Entity_Id;
4710 Err_Loc : Node_Id := Empty;
4711 Skip_Controlling_Formals : Boolean := False)
4714 pragma Warnings (Off, Result);
4717 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
4718 Skip_Controlling_Formals => Skip_Controlling_Formals);
4719 end Check_Subtype_Conformant;
4721 ---------------------------
4722 -- Check_Type_Conformant --
4723 ---------------------------
4725 procedure Check_Type_Conformant
4726 (New_Id : Entity_Id;
4728 Err_Loc : Node_Id := Empty)
4731 pragma Warnings (Off, Result);
4734 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
4735 end Check_Type_Conformant;
4737 ----------------------
4738 -- Conforming_Types --
4739 ----------------------
4741 function Conforming_Types
4744 Ctype : Conformance_Type;
4745 Get_Inst : Boolean := False) return Boolean
4747 Type_1 : Entity_Id := T1;
4748 Type_2 : Entity_Id := T2;
4749 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
4751 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
4752 -- If neither T1 nor T2 are generic actual types, or if they are in
4753 -- different scopes (e.g. parent and child instances), then verify that
4754 -- the base types are equal. Otherwise T1 and T2 must be on the same
4755 -- subtype chain. The whole purpose of this procedure is to prevent
4756 -- spurious ambiguities in an instantiation that may arise if two
4757 -- distinct generic types are instantiated with the same actual.
4759 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
4760 -- An access parameter can designate an incomplete type. If the
4761 -- incomplete type is the limited view of a type from a limited_
4762 -- with_clause, check whether the non-limited view is available. If
4763 -- it is a (non-limited) incomplete type, get the full view.
4765 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
4766 -- Returns True if and only if either T1 denotes a limited view of T2
4767 -- or T2 denotes a limited view of T1. This can arise when the limited
4768 -- with view of a type is used in a subprogram declaration and the
4769 -- subprogram body is in the scope of a regular with clause for the
4770 -- same unit. In such a case, the two type entities can be considered
4771 -- identical for purposes of conformance checking.
4773 ----------------------
4774 -- Base_Types_Match --
4775 ----------------------
4777 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
4782 elsif Base_Type (T1) = Base_Type (T2) then
4784 -- The following is too permissive. A more precise test should
4785 -- check that the generic actual is an ancestor subtype of the
4788 return not Is_Generic_Actual_Type (T1)
4789 or else not Is_Generic_Actual_Type (T2)
4790 or else Scope (T1) /= Scope (T2);
4795 end Base_Types_Match;
4797 --------------------------
4798 -- Find_Designated_Type --
4799 --------------------------
4801 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
4805 Desig := Directly_Designated_Type (T);
4807 if Ekind (Desig) = E_Incomplete_Type then
4809 -- If regular incomplete type, get full view if available
4811 if Present (Full_View (Desig)) then
4812 Desig := Full_View (Desig);
4814 -- If limited view of a type, get non-limited view if available,
4815 -- and check again for a regular incomplete type.
4817 elsif Present (Non_Limited_View (Desig)) then
4818 Desig := Get_Full_View (Non_Limited_View (Desig));
4823 end Find_Designated_Type;
4825 -------------------------------
4826 -- Matches_Limited_With_View --
4827 -------------------------------
4829 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
4831 -- In some cases a type imported through a limited_with clause, and
4832 -- its nonlimited view are both visible, for example in an anonymous
4833 -- access-to-class-wide type in a formal. Both entities designate the
4836 if From_With_Type (T1)
4837 and then T2 = Available_View (T1)
4841 elsif From_With_Type (T2)
4842 and then T1 = Available_View (T2)
4849 end Matches_Limited_With_View;
4851 -- Start of processing for Conforming_Types
4854 -- The context is an instance association for a formal
4855 -- access-to-subprogram type; the formal parameter types require
4856 -- mapping because they may denote other formal parameters of the
4860 Type_1 := Get_Instance_Of (T1);
4861 Type_2 := Get_Instance_Of (T2);
4864 -- If one of the types is a view of the other introduced by a limited
4865 -- with clause, treat these as conforming for all purposes.
4867 if Matches_Limited_With_View (T1, T2) then
4870 elsif Base_Types_Match (Type_1, Type_2) then
4871 return Ctype <= Mode_Conformant
4872 or else Subtypes_Statically_Match (Type_1, Type_2);
4874 elsif Is_Incomplete_Or_Private_Type (Type_1)
4875 and then Present (Full_View (Type_1))
4876 and then Base_Types_Match (Full_View (Type_1), Type_2)
4878 return Ctype <= Mode_Conformant
4879 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
4881 elsif Ekind (Type_2) = E_Incomplete_Type
4882 and then Present (Full_View (Type_2))
4883 and then Base_Types_Match (Type_1, Full_View (Type_2))
4885 return Ctype <= Mode_Conformant
4886 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4888 elsif Is_Private_Type (Type_2)
4889 and then In_Instance
4890 and then Present (Full_View (Type_2))
4891 and then Base_Types_Match (Type_1, Full_View (Type_2))
4893 return Ctype <= Mode_Conformant
4894 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4897 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
4898 -- treated recursively because they carry a signature.
4900 Are_Anonymous_Access_To_Subprogram_Types :=
4901 Ekind (Type_1) = Ekind (Type_2)
4903 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
4905 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
4907 -- Test anonymous access type case. For this case, static subtype
4908 -- matching is required for mode conformance (RM 6.3.1(15)). We check
4909 -- the base types because we may have built internal subtype entities
4910 -- to handle null-excluding types (see Process_Formals).
4912 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
4914 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
4915 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
4918 Desig_1 : Entity_Id;
4919 Desig_2 : Entity_Id;
4922 -- In Ada2005, access constant indicators must match for
4923 -- subtype conformance.
4925 if Ada_Version >= Ada_05
4926 and then Ctype >= Subtype_Conformant
4928 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
4933 Desig_1 := Find_Designated_Type (Type_1);
4935 Desig_2 := Find_Designated_Type (Type_2);
4937 -- If the context is an instance association for a formal
4938 -- access-to-subprogram type; formal access parameter designated
4939 -- types require mapping because they may denote other formal
4940 -- parameters of the generic unit.
4943 Desig_1 := Get_Instance_Of (Desig_1);
4944 Desig_2 := Get_Instance_Of (Desig_2);
4947 -- It is possible for a Class_Wide_Type to be introduced for an
4948 -- incomplete type, in which case there is a separate class_ wide
4949 -- type for the full view. The types conform if their Etypes
4950 -- conform, i.e. one may be the full view of the other. This can
4951 -- only happen in the context of an access parameter, other uses
4952 -- of an incomplete Class_Wide_Type are illegal.
4954 if Is_Class_Wide_Type (Desig_1)
4955 and then Is_Class_Wide_Type (Desig_2)
4959 (Etype (Base_Type (Desig_1)),
4960 Etype (Base_Type (Desig_2)), Ctype);
4962 elsif Are_Anonymous_Access_To_Subprogram_Types then
4963 if Ada_Version < Ada_05 then
4964 return Ctype = Type_Conformant
4966 Subtypes_Statically_Match (Desig_1, Desig_2);
4968 -- We must check the conformance of the signatures themselves
4972 Conformant : Boolean;
4975 (Desig_1, Desig_2, Ctype, False, Conformant);
4981 return Base_Type (Desig_1) = Base_Type (Desig_2)
4982 and then (Ctype = Type_Conformant
4984 Subtypes_Statically_Match (Desig_1, Desig_2));
4988 -- Otherwise definitely no match
4991 if ((Ekind (Type_1) = E_Anonymous_Access_Type
4992 and then Is_Access_Type (Type_2))
4993 or else (Ekind (Type_2) = E_Anonymous_Access_Type
4994 and then Is_Access_Type (Type_1)))
4997 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
4999 May_Hide_Profile := True;
5004 end Conforming_Types;
5006 --------------------------
5007 -- Create_Extra_Formals --
5008 --------------------------
5010 procedure Create_Extra_Formals (E : Entity_Id) is
5012 First_Extra : Entity_Id := Empty;
5013 Last_Extra : Entity_Id;
5014 Formal_Type : Entity_Id;
5015 P_Formal : Entity_Id := Empty;
5017 function Add_Extra_Formal
5018 (Assoc_Entity : Entity_Id;
5021 Suffix : String) return Entity_Id;
5022 -- Add an extra formal to the current list of formals and extra formals.
5023 -- The extra formal is added to the end of the list of extra formals,
5024 -- and also returned as the result. These formals are always of mode IN.
5025 -- The new formal has the type Typ, is declared in Scope, and its name
5026 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
5028 ----------------------
5029 -- Add_Extra_Formal --
5030 ----------------------
5032 function Add_Extra_Formal
5033 (Assoc_Entity : Entity_Id;
5036 Suffix : String) return Entity_Id
5038 EF : constant Entity_Id :=
5039 Make_Defining_Identifier (Sloc (Assoc_Entity),
5040 Chars => New_External_Name (Chars (Assoc_Entity),
5044 -- A little optimization. Never generate an extra formal for the
5045 -- _init operand of an initialization procedure, since it could
5048 if Chars (Formal) = Name_uInit then
5052 Set_Ekind (EF, E_In_Parameter);
5053 Set_Actual_Subtype (EF, Typ);
5054 Set_Etype (EF, Typ);
5055 Set_Scope (EF, Scope);
5056 Set_Mechanism (EF, Default_Mechanism);
5057 Set_Formal_Validity (EF);
5059 if No (First_Extra) then
5061 Set_Extra_Formals (Scope, First_Extra);
5064 if Present (Last_Extra) then
5065 Set_Extra_Formal (Last_Extra, EF);
5071 end Add_Extra_Formal;
5073 -- Start of processing for Create_Extra_Formals
5076 -- We never generate extra formals if expansion is not active
5077 -- because we don't need them unless we are generating code.
5079 if not Expander_Active then
5083 -- If this is a derived subprogram then the subtypes of the parent
5084 -- subprogram's formal parameters will be used to to determine the need
5085 -- for extra formals.
5087 if Is_Overloadable (E) and then Present (Alias (E)) then
5088 P_Formal := First_Formal (Alias (E));
5091 Last_Extra := Empty;
5092 Formal := First_Formal (E);
5093 while Present (Formal) loop
5094 Last_Extra := Formal;
5095 Next_Formal (Formal);
5098 -- If Extra_formals were already created, don't do it again. This
5099 -- situation may arise for subprogram types created as part of
5100 -- dispatching calls (see Expand_Dispatching_Call)
5102 if Present (Last_Extra) and then
5103 Present (Extra_Formal (Last_Extra))
5108 -- If the subprogram is a predefined dispatching subprogram then don't
5109 -- generate any extra constrained or accessibility level formals. In
5110 -- general we suppress these for internal subprograms (by not calling
5111 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
5112 -- generated stream attributes do get passed through because extra
5113 -- build-in-place formals are needed in some cases (limited 'Input).
5115 if Is_Predefined_Dispatching_Operation (E) then
5116 goto Test_For_BIP_Extras;
5119 Formal := First_Formal (E);
5120 while Present (Formal) loop
5122 -- Create extra formal for supporting the attribute 'Constrained.
5123 -- The case of a private type view without discriminants also
5124 -- requires the extra formal if the underlying type has defaulted
5127 if Ekind (Formal) /= E_In_Parameter then
5128 if Present (P_Formal) then
5129 Formal_Type := Etype (P_Formal);
5131 Formal_Type := Etype (Formal);
5134 -- Do not produce extra formals for Unchecked_Union parameters.
5135 -- Jump directly to the end of the loop.
5137 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
5138 goto Skip_Extra_Formal_Generation;
5141 if not Has_Discriminants (Formal_Type)
5142 and then Ekind (Formal_Type) in Private_Kind
5143 and then Present (Underlying_Type (Formal_Type))
5145 Formal_Type := Underlying_Type (Formal_Type);
5148 if Has_Discriminants (Formal_Type)
5149 and then not Is_Constrained (Formal_Type)
5150 and then not Is_Indefinite_Subtype (Formal_Type)
5152 Set_Extra_Constrained
5153 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "F"));
5157 -- Create extra formal for supporting accessibility checking. This
5158 -- is done for both anonymous access formals and formals of named
5159 -- access types that are marked as controlling formals. The latter
5160 -- case can occur when Expand_Dispatching_Call creates a subprogram
5161 -- type and substitutes the types of access-to-class-wide actuals
5162 -- for the anonymous access-to-specific-type of controlling formals.
5163 -- Base_Type is applied because in cases where there is a null
5164 -- exclusion the formal may have an access subtype.
5166 -- This is suppressed if we specifically suppress accessibility
5167 -- checks at the package level for either the subprogram, or the
5168 -- package in which it resides. However, we do not suppress it
5169 -- simply if the scope has accessibility checks suppressed, since
5170 -- this could cause trouble when clients are compiled with a
5171 -- different suppression setting. The explicit checks at the
5172 -- package level are safe from this point of view.
5174 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
5175 or else (Is_Controlling_Formal (Formal)
5176 and then Is_Access_Type (Base_Type (Etype (Formal)))))
5178 (Explicit_Suppress (E, Accessibility_Check)
5180 Explicit_Suppress (Scope (E), Accessibility_Check))
5183 or else Present (Extra_Accessibility (P_Formal)))
5185 -- Temporary kludge: for now we avoid creating the extra formal
5186 -- for access parameters of protected operations because of
5187 -- problem with the case of internal protected calls. ???
5189 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
5190 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
5192 Set_Extra_Accessibility
5193 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "F"));
5197 -- This label is required when skipping extra formal generation for
5198 -- Unchecked_Union parameters.
5200 <<Skip_Extra_Formal_Generation>>
5202 if Present (P_Formal) then
5203 Next_Formal (P_Formal);
5206 Next_Formal (Formal);
5209 <<Test_For_BIP_Extras>>
5211 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
5212 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
5214 if Ada_Version >= Ada_05 and then Is_Build_In_Place_Function (E) then
5216 Result_Subt : constant Entity_Id := Etype (E);
5218 Discard : Entity_Id;
5219 pragma Warnings (Off, Discard);
5222 -- In the case of functions with unconstrained result subtypes,
5223 -- add a 3-state formal indicating whether the return object is
5224 -- allocated by the caller (0), or should be allocated by the
5225 -- callee on the secondary stack (1) or in the global heap (2).
5226 -- For the moment we just use Natural for the type of this formal.
5227 -- Note that this formal isn't usually needed in the case where
5228 -- the result subtype is constrained, but it is needed when the
5229 -- function has a tagged result, because generally such functions
5230 -- can be called in a dispatching context and such calls must be
5231 -- handled like calls to a class-wide function.
5233 if not Is_Constrained (Underlying_Type (Result_Subt))
5234 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
5238 (E, Standard_Natural,
5239 E, BIP_Formal_Suffix (BIP_Alloc_Form));
5242 -- In the case of functions whose result type has controlled
5243 -- parts, we have an extra formal of type
5244 -- System.Finalization_Implementation.Finalizable_Ptr_Ptr. That
5245 -- is, we are passing a pointer to a finalization list (which is
5246 -- itself a pointer). This extra formal is then passed along to
5247 -- Move_Final_List in case of successful completion of a return
5248 -- statement. We cannot pass an 'in out' parameter, because we
5249 -- need to update the finalization list during an abort-deferred
5250 -- region, rather than using copy-back after the function
5251 -- returns. This is true even if we are able to get away with
5252 -- having 'in out' parameters, which are normally illegal for
5253 -- functions. This formal is also needed when the function has
5254 -- a tagged result, because generally such functions can be called
5255 -- in a dispatching context and such calls must be handled like
5256 -- calls to class-wide functions.
5258 if Controlled_Type (Result_Subt)
5259 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
5263 (E, RTE (RE_Finalizable_Ptr_Ptr),
5264 E, BIP_Formal_Suffix (BIP_Final_List));
5267 -- If the result type contains tasks, we have two extra formals:
5268 -- the master of the tasks to be created, and the caller's
5269 -- activation chain.
5271 if Has_Task (Result_Subt) then
5274 (E, RTE (RE_Master_Id),
5275 E, BIP_Formal_Suffix (BIP_Master));
5278 (E, RTE (RE_Activation_Chain_Access),
5279 E, BIP_Formal_Suffix (BIP_Activation_Chain));
5282 -- All build-in-place functions get an extra formal that will be
5283 -- passed the address of the return object within the caller.
5286 Formal_Type : constant Entity_Id :=
5288 (E_Anonymous_Access_Type, E,
5289 Scope_Id => Scope (E));
5291 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
5292 Set_Etype (Formal_Type, Formal_Type);
5293 Set_Depends_On_Private
5294 (Formal_Type, Has_Private_Component (Formal_Type));
5295 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
5296 Set_Is_Access_Constant (Formal_Type, False);
5298 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
5299 -- the designated type comes from the limited view (for
5300 -- back-end purposes).
5302 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
5304 Layout_Type (Formal_Type);
5308 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
5312 end Create_Extra_Formals;
5314 -----------------------------
5315 -- Enter_Overloaded_Entity --
5316 -----------------------------
5318 procedure Enter_Overloaded_Entity (S : Entity_Id) is
5319 E : Entity_Id := Current_Entity_In_Scope (S);
5320 C_E : Entity_Id := Current_Entity (S);
5324 Set_Has_Homonym (E);
5325 Set_Has_Homonym (S);
5328 Set_Is_Immediately_Visible (S);
5329 Set_Scope (S, Current_Scope);
5331 -- Chain new entity if front of homonym in current scope, so that
5332 -- homonyms are contiguous.
5337 while Homonym (C_E) /= E loop
5338 C_E := Homonym (C_E);
5341 Set_Homonym (C_E, S);
5345 Set_Current_Entity (S);
5350 Append_Entity (S, Current_Scope);
5351 Set_Public_Status (S);
5353 if Debug_Flag_E then
5354 Write_Str ("New overloaded entity chain: ");
5355 Write_Name (Chars (S));
5358 while Present (E) loop
5359 Write_Str (" "); Write_Int (Int (E));
5366 -- Generate warning for hiding
5369 and then Comes_From_Source (S)
5370 and then In_Extended_Main_Source_Unit (S)
5377 -- Warn unless genuine overloading
5379 if (not Is_Overloadable (E) or else Subtype_Conformant (E, S))
5380 and then (Is_Immediately_Visible (E)
5382 Is_Potentially_Use_Visible (S))
5384 Error_Msg_Sloc := Sloc (E);
5385 Error_Msg_N ("declaration of & hides one#?", S);
5389 end Enter_Overloaded_Entity;
5391 -----------------------------
5392 -- Find_Corresponding_Spec --
5393 -----------------------------
5395 function Find_Corresponding_Spec
5397 Post_Error : Boolean := True) return Entity_Id
5399 Spec : constant Node_Id := Specification (N);
5400 Designator : constant Entity_Id := Defining_Entity (Spec);
5405 E := Current_Entity (Designator);
5406 while Present (E) loop
5408 -- We are looking for a matching spec. It must have the same scope,
5409 -- and the same name, and either be type conformant, or be the case
5410 -- of a library procedure spec and its body (which belong to one
5411 -- another regardless of whether they are type conformant or not).
5413 if Scope (E) = Current_Scope then
5414 if Current_Scope = Standard_Standard
5415 or else (Ekind (E) = Ekind (Designator)
5416 and then Type_Conformant (E, Designator))
5418 -- Within an instantiation, we know that spec and body are
5419 -- subtype conformant, because they were subtype conformant
5420 -- in the generic. We choose the subtype-conformant entity
5421 -- here as well, to resolve spurious ambiguities in the
5422 -- instance that were not present in the generic (i.e. when
5423 -- two different types are given the same actual). If we are
5424 -- looking for a spec to match a body, full conformance is
5428 Set_Convention (Designator, Convention (E));
5430 if Nkind (N) = N_Subprogram_Body
5431 and then Present (Homonym (E))
5432 and then not Fully_Conformant (E, Designator)
5436 elsif not Subtype_Conformant (E, Designator) then
5441 if not Has_Completion (E) then
5442 if Nkind (N) /= N_Subprogram_Body_Stub then
5443 Set_Corresponding_Spec (N, E);
5446 Set_Has_Completion (E);
5449 elsif Nkind (Parent (N)) = N_Subunit then
5451 -- If this is the proper body of a subunit, the completion
5452 -- flag is set when analyzing the stub.
5456 -- If E is an internal function with a controlling result
5457 -- that was created for an operation inherited by a null
5458 -- extension, it may be overridden by a body without a previous
5459 -- spec (one more reason why these should be shunned). In that
5460 -- case remove the generated body, because the current one is
5461 -- the explicit overriding.
5463 elsif Ekind (E) = E_Function
5464 and then Ada_Version >= Ada_05
5465 and then not Comes_From_Source (E)
5466 and then Has_Controlling_Result (E)
5467 and then Is_Null_Extension (Etype (E))
5468 and then Comes_From_Source (Spec)
5470 Set_Has_Completion (E, False);
5472 if Expander_Active then
5474 (Unit_Declaration_Node
5475 (Corresponding_Body (Unit_Declaration_Node (E))));
5478 -- If expansion is disabled, the wrapper function has not
5479 -- been generated, and this is the standard case of a late
5480 -- body overriding an inherited operation.
5486 -- If the body already exists, then this is an error unless
5487 -- the previous declaration is the implicit declaration of a
5488 -- derived subprogram, or this is a spurious overloading in an
5491 elsif No (Alias (E))
5492 and then not Is_Intrinsic_Subprogram (E)
5493 and then not In_Instance
5496 Error_Msg_Sloc := Sloc (E);
5497 if Is_Imported (E) then
5499 ("body not allowed for imported subprogram & declared#",
5502 Error_Msg_NE ("duplicate body for & declared#", N, E);
5506 -- Child units cannot be overloaded, so a conformance mismatch
5507 -- between body and a previous spec is an error.
5509 elsif Is_Child_Unit (E)
5511 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
5513 Nkind (Parent (Unit_Declaration_Node (Designator))) =
5518 ("body of child unit does not match previous declaration", N);
5526 -- On exit, we know that no previous declaration of subprogram exists
5529 end Find_Corresponding_Spec;
5531 ----------------------
5532 -- Fully_Conformant --
5533 ----------------------
5535 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5538 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
5540 end Fully_Conformant;
5542 ----------------------------------
5543 -- Fully_Conformant_Expressions --
5544 ----------------------------------
5546 function Fully_Conformant_Expressions
5547 (Given_E1 : Node_Id;
5548 Given_E2 : Node_Id) return Boolean
5550 E1 : constant Node_Id := Original_Node (Given_E1);
5551 E2 : constant Node_Id := Original_Node (Given_E2);
5552 -- We always test conformance on original nodes, since it is possible
5553 -- for analysis and/or expansion to make things look as though they
5554 -- conform when they do not, e.g. by converting 1+2 into 3.
5556 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
5557 renames Fully_Conformant_Expressions;
5559 function FCL (L1, L2 : List_Id) return Boolean;
5560 -- Compare elements of two lists for conformance. Elements have to
5561 -- be conformant, and actuals inserted as default parameters do not
5562 -- match explicit actuals with the same value.
5564 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
5565 -- Compare an operator node with a function call
5571 function FCL (L1, L2 : List_Id) return Boolean is
5575 if L1 = No_List then
5581 if L2 = No_List then
5587 -- Compare two lists, skipping rewrite insertions (we want to
5588 -- compare the original trees, not the expanded versions!)
5591 if Is_Rewrite_Insertion (N1) then
5593 elsif Is_Rewrite_Insertion (N2) then
5599 elsif not FCE (N1, N2) then
5612 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
5613 Actuals : constant List_Id := Parameter_Associations (Call_Node);
5618 or else Entity (Op_Node) /= Entity (Name (Call_Node))
5623 Act := First (Actuals);
5625 if Nkind (Op_Node) in N_Binary_Op then
5627 if not FCE (Left_Opnd (Op_Node), Act) then
5634 return Present (Act)
5635 and then FCE (Right_Opnd (Op_Node), Act)
5636 and then No (Next (Act));
5640 -- Start of processing for Fully_Conformant_Expressions
5643 -- Non-conformant if paren count does not match. Note: if some idiot
5644 -- complains that we don't do this right for more than 3 levels of
5645 -- parentheses, they will be treated with the respect they deserve!
5647 if Paren_Count (E1) /= Paren_Count (E2) then
5650 -- If same entities are referenced, then they are conformant even if
5651 -- they have different forms (RM 8.3.1(19-20)).
5653 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
5654 if Present (Entity (E1)) then
5655 return Entity (E1) = Entity (E2)
5656 or else (Chars (Entity (E1)) = Chars (Entity (E2))
5657 and then Ekind (Entity (E1)) = E_Discriminant
5658 and then Ekind (Entity (E2)) = E_In_Parameter);
5660 elsif Nkind (E1) = N_Expanded_Name
5661 and then Nkind (E2) = N_Expanded_Name
5662 and then Nkind (Selector_Name (E1)) = N_Character_Literal
5663 and then Nkind (Selector_Name (E2)) = N_Character_Literal
5665 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
5668 -- Identifiers in component associations don't always have
5669 -- entities, but their names must conform.
5671 return Nkind (E1) = N_Identifier
5672 and then Nkind (E2) = N_Identifier
5673 and then Chars (E1) = Chars (E2);
5676 elsif Nkind (E1) = N_Character_Literal
5677 and then Nkind (E2) = N_Expanded_Name
5679 return Nkind (Selector_Name (E2)) = N_Character_Literal
5680 and then Chars (E1) = Chars (Selector_Name (E2));
5682 elsif Nkind (E2) = N_Character_Literal
5683 and then Nkind (E1) = N_Expanded_Name
5685 return Nkind (Selector_Name (E1)) = N_Character_Literal
5686 and then Chars (E2) = Chars (Selector_Name (E1));
5688 elsif Nkind (E1) in N_Op
5689 and then Nkind (E2) = N_Function_Call
5691 return FCO (E1, E2);
5693 elsif Nkind (E2) in N_Op
5694 and then Nkind (E1) = N_Function_Call
5696 return FCO (E2, E1);
5698 -- Otherwise we must have the same syntactic entity
5700 elsif Nkind (E1) /= Nkind (E2) then
5703 -- At this point, we specialize by node type
5710 FCL (Expressions (E1), Expressions (E2))
5711 and then FCL (Component_Associations (E1),
5712 Component_Associations (E2));
5715 if Nkind (Expression (E1)) = N_Qualified_Expression
5717 Nkind (Expression (E2)) = N_Qualified_Expression
5719 return FCE (Expression (E1), Expression (E2));
5721 -- Check that the subtype marks and any constraints
5726 Indic1 : constant Node_Id := Expression (E1);
5727 Indic2 : constant Node_Id := Expression (E2);
5732 if Nkind (Indic1) /= N_Subtype_Indication then
5734 Nkind (Indic2) /= N_Subtype_Indication
5735 and then Entity (Indic1) = Entity (Indic2);
5737 elsif Nkind (Indic2) /= N_Subtype_Indication then
5739 Nkind (Indic1) /= N_Subtype_Indication
5740 and then Entity (Indic1) = Entity (Indic2);
5743 if Entity (Subtype_Mark (Indic1)) /=
5744 Entity (Subtype_Mark (Indic2))
5749 Elt1 := First (Constraints (Constraint (Indic1)));
5750 Elt2 := First (Constraints (Constraint (Indic2)));
5752 while Present (Elt1) and then Present (Elt2) loop
5753 if not FCE (Elt1, Elt2) then
5766 when N_Attribute_Reference =>
5768 Attribute_Name (E1) = Attribute_Name (E2)
5769 and then FCL (Expressions (E1), Expressions (E2));
5773 Entity (E1) = Entity (E2)
5774 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
5775 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5777 when N_And_Then | N_Or_Else | N_Membership_Test =>
5779 FCE (Left_Opnd (E1), Left_Opnd (E2))
5781 FCE (Right_Opnd (E1), Right_Opnd (E2));
5783 when N_Character_Literal =>
5785 Char_Literal_Value (E1) = Char_Literal_Value (E2);
5787 when N_Component_Association =>
5789 FCL (Choices (E1), Choices (E2))
5790 and then FCE (Expression (E1), Expression (E2));
5792 when N_Conditional_Expression =>
5794 FCL (Expressions (E1), Expressions (E2));
5796 when N_Explicit_Dereference =>
5798 FCE (Prefix (E1), Prefix (E2));
5800 when N_Extension_Aggregate =>
5802 FCL (Expressions (E1), Expressions (E2))
5803 and then Null_Record_Present (E1) =
5804 Null_Record_Present (E2)
5805 and then FCL (Component_Associations (E1),
5806 Component_Associations (E2));
5808 when N_Function_Call =>
5810 FCE (Name (E1), Name (E2))
5811 and then FCL (Parameter_Associations (E1),
5812 Parameter_Associations (E2));
5814 when N_Indexed_Component =>
5816 FCE (Prefix (E1), Prefix (E2))
5817 and then FCL (Expressions (E1), Expressions (E2));
5819 when N_Integer_Literal =>
5820 return (Intval (E1) = Intval (E2));
5825 when N_Operator_Symbol =>
5827 Chars (E1) = Chars (E2);
5829 when N_Others_Choice =>
5832 when N_Parameter_Association =>
5834 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
5835 and then FCE (Explicit_Actual_Parameter (E1),
5836 Explicit_Actual_Parameter (E2));
5838 when N_Qualified_Expression =>
5840 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5841 and then FCE (Expression (E1), Expression (E2));
5845 FCE (Low_Bound (E1), Low_Bound (E2))
5846 and then FCE (High_Bound (E1), High_Bound (E2));
5848 when N_Real_Literal =>
5849 return (Realval (E1) = Realval (E2));
5851 when N_Selected_Component =>
5853 FCE (Prefix (E1), Prefix (E2))
5854 and then FCE (Selector_Name (E1), Selector_Name (E2));
5858 FCE (Prefix (E1), Prefix (E2))
5859 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
5861 when N_String_Literal =>
5863 S1 : constant String_Id := Strval (E1);
5864 S2 : constant String_Id := Strval (E2);
5865 L1 : constant Nat := String_Length (S1);
5866 L2 : constant Nat := String_Length (S2);
5873 for J in 1 .. L1 loop
5874 if Get_String_Char (S1, J) /=
5875 Get_String_Char (S2, J)
5885 when N_Type_Conversion =>
5887 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5888 and then FCE (Expression (E1), Expression (E2));
5892 Entity (E1) = Entity (E2)
5893 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5895 when N_Unchecked_Type_Conversion =>
5897 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5898 and then FCE (Expression (E1), Expression (E2));
5900 -- All other node types cannot appear in this context. Strictly
5901 -- we should raise a fatal internal error. Instead we just ignore
5902 -- the nodes. This means that if anyone makes a mistake in the
5903 -- expander and mucks an expression tree irretrievably, the
5904 -- result will be a failure to detect a (probably very obscure)
5905 -- case of non-conformance, which is better than bombing on some
5906 -- case where two expressions do in fact conform.
5913 end Fully_Conformant_Expressions;
5915 ----------------------------------------
5916 -- Fully_Conformant_Discrete_Subtypes --
5917 ----------------------------------------
5919 function Fully_Conformant_Discrete_Subtypes
5920 (Given_S1 : Node_Id;
5921 Given_S2 : Node_Id) return Boolean
5923 S1 : constant Node_Id := Original_Node (Given_S1);
5924 S2 : constant Node_Id := Original_Node (Given_S2);
5926 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
5927 -- Special-case for a bound given by a discriminant, which in the body
5928 -- is replaced with the discriminal of the enclosing type.
5930 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
5931 -- Check both bounds
5933 -----------------------
5934 -- Conforming_Bounds --
5935 -----------------------
5937 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
5939 if Is_Entity_Name (B1)
5940 and then Is_Entity_Name (B2)
5941 and then Ekind (Entity (B1)) = E_Discriminant
5943 return Chars (B1) = Chars (B2);
5946 return Fully_Conformant_Expressions (B1, B2);
5948 end Conforming_Bounds;
5950 -----------------------
5951 -- Conforming_Ranges --
5952 -----------------------
5954 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
5957 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
5959 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
5960 end Conforming_Ranges;
5962 -- Start of processing for Fully_Conformant_Discrete_Subtypes
5965 if Nkind (S1) /= Nkind (S2) then
5968 elsif Is_Entity_Name (S1) then
5969 return Entity (S1) = Entity (S2);
5971 elsif Nkind (S1) = N_Range then
5972 return Conforming_Ranges (S1, S2);
5974 elsif Nkind (S1) = N_Subtype_Indication then
5976 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
5979 (Range_Expression (Constraint (S1)),
5980 Range_Expression (Constraint (S2)));
5984 end Fully_Conformant_Discrete_Subtypes;
5986 --------------------
5987 -- Install_Entity --
5988 --------------------
5990 procedure Install_Entity (E : Entity_Id) is
5991 Prev : constant Entity_Id := Current_Entity (E);
5993 Set_Is_Immediately_Visible (E);
5994 Set_Current_Entity (E);
5995 Set_Homonym (E, Prev);
5998 ---------------------
5999 -- Install_Formals --
6000 ---------------------
6002 procedure Install_Formals (Id : Entity_Id) is
6005 F := First_Formal (Id);
6006 while Present (F) loop
6010 end Install_Formals;
6012 -----------------------------
6013 -- Is_Interface_Conformant --
6014 -----------------------------
6016 function Is_Interface_Conformant
6017 (Tagged_Type : Entity_Id;
6018 Iface_Prim : Entity_Id;
6019 Prim : Entity_Id) return Boolean
6021 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
6022 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
6025 pragma Assert (Is_Subprogram (Iface_Prim)
6026 and then Is_Subprogram (Prim)
6027 and then Is_Dispatching_Operation (Iface_Prim)
6028 and then Is_Dispatching_Operation (Prim));
6030 pragma Assert (Is_Interface (Iface)
6031 or else (Present (Alias (Iface_Prim))
6034 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
6036 if Prim = Iface_Prim
6037 or else not Is_Subprogram (Prim)
6038 or else Ekind (Prim) /= Ekind (Iface_Prim)
6039 or else not Is_Dispatching_Operation (Prim)
6040 or else Scope (Prim) /= Scope (Tagged_Type)
6042 or else Base_Type (Typ) /= Tagged_Type
6043 or else not Primitive_Names_Match (Iface_Prim, Prim)
6047 -- Case of a procedure, or a function that does not have a controlling
6048 -- result (I or access I).
6050 elsif Ekind (Iface_Prim) = E_Procedure
6051 or else Etype (Prim) = Etype (Iface_Prim)
6052 or else not Has_Controlling_Result (Prim)
6054 return Type_Conformant (Prim, Iface_Prim,
6055 Skip_Controlling_Formals => True);
6057 -- Case of a function returning an interface, or an access to one.
6058 -- Check that the return types correspond.
6060 elsif Implements_Interface (Typ, Iface) then
6061 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
6063 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
6068 Type_Conformant (Prim, Iface_Prim,
6069 Skip_Controlling_Formals => True);
6075 end Is_Interface_Conformant;
6077 ---------------------------------
6078 -- Is_Non_Overriding_Operation --
6079 ---------------------------------
6081 function Is_Non_Overriding_Operation
6082 (Prev_E : Entity_Id;
6083 New_E : Entity_Id) return Boolean
6087 G_Typ : Entity_Id := Empty;
6089 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
6090 -- If F_Type is a derived type associated with a generic actual subtype,
6091 -- then return its Generic_Parent_Type attribute, else return Empty.
6093 function Types_Correspond
6094 (P_Type : Entity_Id;
6095 N_Type : Entity_Id) return Boolean;
6096 -- Returns true if and only if the types (or designated types in the
6097 -- case of anonymous access types) are the same or N_Type is derived
6098 -- directly or indirectly from P_Type.
6100 -----------------------------
6101 -- Get_Generic_Parent_Type --
6102 -----------------------------
6104 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
6109 if Is_Derived_Type (F_Typ)
6110 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
6112 -- The tree must be traversed to determine the parent subtype in
6113 -- the generic unit, which unfortunately isn't always available
6114 -- via semantic attributes. ??? (Note: The use of Original_Node
6115 -- is needed for cases where a full derived type has been
6118 Indic := Subtype_Indication
6119 (Type_Definition (Original_Node (Parent (F_Typ))));
6121 if Nkind (Indic) = N_Subtype_Indication then
6122 G_Typ := Entity (Subtype_Mark (Indic));
6124 G_Typ := Entity (Indic);
6127 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
6128 and then Present (Generic_Parent_Type (Parent (G_Typ)))
6130 return Generic_Parent_Type (Parent (G_Typ));
6135 end Get_Generic_Parent_Type;
6137 ----------------------
6138 -- Types_Correspond --
6139 ----------------------
6141 function Types_Correspond
6142 (P_Type : Entity_Id;
6143 N_Type : Entity_Id) return Boolean
6145 Prev_Type : Entity_Id := Base_Type (P_Type);
6146 New_Type : Entity_Id := Base_Type (N_Type);
6149 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
6150 Prev_Type := Designated_Type (Prev_Type);
6153 if Ekind (New_Type) = E_Anonymous_Access_Type then
6154 New_Type := Designated_Type (New_Type);
6157 if Prev_Type = New_Type then
6160 elsif not Is_Class_Wide_Type (New_Type) then
6161 while Etype (New_Type) /= New_Type loop
6162 New_Type := Etype (New_Type);
6163 if New_Type = Prev_Type then
6169 end Types_Correspond;
6171 -- Start of processing for Is_Non_Overriding_Operation
6174 -- In the case where both operations are implicit derived subprograms
6175 -- then neither overrides the other. This can only occur in certain
6176 -- obscure cases (e.g., derivation from homographs created in a generic
6179 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
6182 elsif Ekind (Current_Scope) = E_Package
6183 and then Is_Generic_Instance (Current_Scope)
6184 and then In_Private_Part (Current_Scope)
6185 and then Comes_From_Source (New_E)
6187 -- We examine the formals and result subtype of the inherited
6188 -- operation, to determine whether their type is derived from (the
6189 -- instance of) a generic type.
6191 Formal := First_Formal (Prev_E);
6193 while Present (Formal) loop
6194 F_Typ := Base_Type (Etype (Formal));
6196 if Ekind (F_Typ) = E_Anonymous_Access_Type then
6197 F_Typ := Designated_Type (F_Typ);
6200 G_Typ := Get_Generic_Parent_Type (F_Typ);
6202 Next_Formal (Formal);
6205 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
6206 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
6213 -- If the generic type is a private type, then the original
6214 -- operation was not overriding in the generic, because there was
6215 -- no primitive operation to override.
6217 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
6218 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
6219 N_Formal_Private_Type_Definition
6223 -- The generic parent type is the ancestor of a formal derived
6224 -- type declaration. We need to check whether it has a primitive
6225 -- operation that should be overridden by New_E in the generic.
6229 P_Formal : Entity_Id;
6230 N_Formal : Entity_Id;
6234 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
6237 while Present (Prim_Elt) loop
6238 P_Prim := Node (Prim_Elt);
6240 if Chars (P_Prim) = Chars (New_E)
6241 and then Ekind (P_Prim) = Ekind (New_E)
6243 P_Formal := First_Formal (P_Prim);
6244 N_Formal := First_Formal (New_E);
6245 while Present (P_Formal) and then Present (N_Formal) loop
6246 P_Typ := Etype (P_Formal);
6247 N_Typ := Etype (N_Formal);
6249 if not Types_Correspond (P_Typ, N_Typ) then
6253 Next_Entity (P_Formal);
6254 Next_Entity (N_Formal);
6257 -- Found a matching primitive operation belonging to the
6258 -- formal ancestor type, so the new subprogram is
6262 and then No (N_Formal)
6263 and then (Ekind (New_E) /= E_Function
6266 (Etype (P_Prim), Etype (New_E)))
6272 Next_Elmt (Prim_Elt);
6275 -- If no match found, then the new subprogram does not
6276 -- override in the generic (nor in the instance).
6284 end Is_Non_Overriding_Operation;
6286 ------------------------------
6287 -- Make_Inequality_Operator --
6288 ------------------------------
6290 -- S is the defining identifier of an equality operator. We build a
6291 -- subprogram declaration with the right signature. This operation is
6292 -- intrinsic, because it is always expanded as the negation of the
6293 -- call to the equality function.
6295 procedure Make_Inequality_Operator (S : Entity_Id) is
6296 Loc : constant Source_Ptr := Sloc (S);
6299 Op_Name : Entity_Id;
6301 FF : constant Entity_Id := First_Formal (S);
6302 NF : constant Entity_Id := Next_Formal (FF);
6305 -- Check that equality was properly defined, ignore call if not
6312 A : constant Entity_Id :=
6313 Make_Defining_Identifier (Sloc (FF),
6314 Chars => Chars (FF));
6316 B : constant Entity_Id :=
6317 Make_Defining_Identifier (Sloc (NF),
6318 Chars => Chars (NF));
6321 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
6323 Formals := New_List (
6324 Make_Parameter_Specification (Loc,
6325 Defining_Identifier => A,
6327 New_Reference_To (Etype (First_Formal (S)),
6328 Sloc (Etype (First_Formal (S))))),
6330 Make_Parameter_Specification (Loc,
6331 Defining_Identifier => B,
6333 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
6334 Sloc (Etype (Next_Formal (First_Formal (S)))))));
6337 Make_Subprogram_Declaration (Loc,
6339 Make_Function_Specification (Loc,
6340 Defining_Unit_Name => Op_Name,
6341 Parameter_Specifications => Formals,
6342 Result_Definition =>
6343 New_Reference_To (Standard_Boolean, Loc)));
6345 -- Insert inequality right after equality if it is explicit or after
6346 -- the derived type when implicit. These entities are created only
6347 -- for visibility purposes, and eventually replaced in the course of
6348 -- expansion, so they do not need to be attached to the tree and seen
6349 -- by the back-end. Keeping them internal also avoids spurious
6350 -- freezing problems. The declaration is inserted in the tree for
6351 -- analysis, and removed afterwards. If the equality operator comes
6352 -- from an explicit declaration, attach the inequality immediately
6353 -- after. Else the equality is inherited from a derived type
6354 -- declaration, so insert inequality after that declaration.
6356 if No (Alias (S)) then
6357 Insert_After (Unit_Declaration_Node (S), Decl);
6358 elsif Is_List_Member (Parent (S)) then
6359 Insert_After (Parent (S), Decl);
6361 Insert_After (Parent (Etype (First_Formal (S))), Decl);
6364 Mark_Rewrite_Insertion (Decl);
6365 Set_Is_Intrinsic_Subprogram (Op_Name);
6368 Set_Has_Completion (Op_Name);
6369 Set_Corresponding_Equality (Op_Name, S);
6370 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
6372 end Make_Inequality_Operator;
6374 ----------------------
6375 -- May_Need_Actuals --
6376 ----------------------
6378 procedure May_Need_Actuals (Fun : Entity_Id) is
6383 F := First_Formal (Fun);
6385 while Present (F) loop
6386 if No (Default_Value (F)) then
6394 Set_Needs_No_Actuals (Fun, B);
6395 end May_Need_Actuals;
6397 ---------------------
6398 -- Mode_Conformant --
6399 ---------------------
6401 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6404 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
6406 end Mode_Conformant;
6408 ---------------------------
6409 -- New_Overloaded_Entity --
6410 ---------------------------
6412 procedure New_Overloaded_Entity
6414 Derived_Type : Entity_Id := Empty)
6416 Overridden_Subp : Entity_Id := Empty;
6417 -- Set if the current scope has an operation that is type-conformant
6418 -- with S, and becomes hidden by S.
6420 Is_Primitive_Subp : Boolean;
6421 -- Set to True if the new subprogram is primitive
6424 -- Entity that S overrides
6426 Prev_Vis : Entity_Id := Empty;
6427 -- Predecessor of E in Homonym chain
6429 procedure Check_For_Primitive_Subprogram
6430 (Is_Primitive : out Boolean;
6431 Is_Overriding : Boolean := False);
6432 -- If the subprogram being analyzed is a primitive operation of the type
6433 -- of a formal or result, set the Has_Primitive_Operations flag on the
6434 -- type, and set Is_Primitive to True (otherwise set to False). Set the
6435 -- corresponding flag on the entity itself for later use.
6437 procedure Check_Synchronized_Overriding
6438 (Def_Id : Entity_Id;
6439 Overridden_Subp : out Entity_Id);
6440 -- First determine if Def_Id is an entry or a subprogram either defined
6441 -- in the scope of a task or protected type, or is a primitive of such
6442 -- a type. Check whether Def_Id overrides a subprogram of an interface
6443 -- implemented by the synchronized type, return the overridden entity
6446 function Is_Private_Declaration (E : Entity_Id) return Boolean;
6447 -- Check that E is declared in the private part of the current package,
6448 -- or in the package body, where it may hide a previous declaration.
6449 -- We can't use In_Private_Part by itself because this flag is also
6450 -- set when freezing entities, so we must examine the place of the
6451 -- declaration in the tree, and recognize wrapper packages as well.
6453 ------------------------------------
6454 -- Check_For_Primitive_Subprogram --
6455 ------------------------------------
6457 procedure Check_For_Primitive_Subprogram
6458 (Is_Primitive : out Boolean;
6459 Is_Overriding : Boolean := False)
6465 function Visible_Part_Type (T : Entity_Id) return Boolean;
6466 -- Returns true if T is declared in the visible part of
6467 -- the current package scope; otherwise returns false.
6468 -- Assumes that T is declared in a package.
6470 procedure Check_Private_Overriding (T : Entity_Id);
6471 -- Checks that if a primitive abstract subprogram of a visible
6472 -- abstract type is declared in a private part, then it must
6473 -- override an abstract subprogram declared in the visible part.
6474 -- Also checks that if a primitive function with a controlling
6475 -- result is declared in a private part, then it must override
6476 -- a function declared in the visible part.
6478 ------------------------------
6479 -- Check_Private_Overriding --
6480 ------------------------------
6482 procedure Check_Private_Overriding (T : Entity_Id) is
6484 if Ekind (Current_Scope) = E_Package
6485 and then In_Private_Part (Current_Scope)
6486 and then Visible_Part_Type (T)
6487 and then not In_Instance
6489 if Is_Abstract_Type (T)
6490 and then Is_Abstract_Subprogram (S)
6491 and then (not Is_Overriding
6492 or else not Is_Abstract_Subprogram (E))
6494 Error_Msg_N ("abstract subprograms must be visible "
6495 & "(RM 3.9.3(10))!", S);
6497 elsif Ekind (S) = E_Function
6498 and then Is_Tagged_Type (T)
6499 and then T = Base_Type (Etype (S))
6500 and then not Is_Overriding
6503 ("private function with tagged result must"
6504 & " override visible-part function", S);
6506 ("\move subprogram to the visible part"
6507 & " (RM 3.9.3(10))", S);
6510 end Check_Private_Overriding;
6512 -----------------------
6513 -- Visible_Part_Type --
6514 -----------------------
6516 function Visible_Part_Type (T : Entity_Id) return Boolean is
6517 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
6521 -- If the entity is a private type, then it must be
6522 -- declared in a visible part.
6524 if Ekind (T) in Private_Kind then
6528 -- Otherwise, we traverse the visible part looking for its
6529 -- corresponding declaration. We cannot use the declaration
6530 -- node directly because in the private part the entity of a
6531 -- private type is the one in the full view, which does not
6532 -- indicate that it is the completion of something visible.
6534 N := First (Visible_Declarations (Specification (P)));
6535 while Present (N) loop
6536 if Nkind (N) = N_Full_Type_Declaration
6537 and then Present (Defining_Identifier (N))
6538 and then T = Defining_Identifier (N)
6542 elsif Nkind_In (N, N_Private_Type_Declaration,
6543 N_Private_Extension_Declaration)
6544 and then Present (Defining_Identifier (N))
6545 and then T = Full_View (Defining_Identifier (N))
6554 end Visible_Part_Type;
6556 -- Start of processing for Check_For_Primitive_Subprogram
6559 Is_Primitive := False;
6561 if not Comes_From_Source (S) then
6564 -- If subprogram is at library level, it is not primitive operation
6566 elsif Current_Scope = Standard_Standard then
6569 elsif ((Ekind (Current_Scope) = E_Package
6570 or else Ekind (Current_Scope) = E_Generic_Package)
6571 and then not In_Package_Body (Current_Scope))
6572 or else Is_Overriding
6574 -- For function, check return type
6576 if Ekind (S) = E_Function then
6577 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
6578 F_Typ := Designated_Type (Etype (S));
6583 B_Typ := Base_Type (F_Typ);
6585 if Scope (B_Typ) = Current_Scope
6586 and then not Is_Class_Wide_Type (B_Typ)
6587 and then not Is_Generic_Type (B_Typ)
6589 Is_Primitive := True;
6590 Set_Has_Primitive_Operations (B_Typ);
6591 Set_Is_Primitive (S);
6592 Check_Private_Overriding (B_Typ);
6596 -- For all subprograms, check formals
6598 Formal := First_Formal (S);
6599 while Present (Formal) loop
6600 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
6601 F_Typ := Designated_Type (Etype (Formal));
6603 F_Typ := Etype (Formal);
6606 B_Typ := Base_Type (F_Typ);
6608 if Ekind (B_Typ) = E_Access_Subtype then
6609 B_Typ := Base_Type (B_Typ);
6612 if Scope (B_Typ) = Current_Scope
6613 and then not Is_Class_Wide_Type (B_Typ)
6614 and then not Is_Generic_Type (B_Typ)
6616 Is_Primitive := True;
6617 Set_Is_Primitive (S);
6618 Set_Has_Primitive_Operations (B_Typ);
6619 Check_Private_Overriding (B_Typ);
6622 Next_Formal (Formal);
6625 end Check_For_Primitive_Subprogram;
6627 -----------------------------------
6628 -- Check_Synchronized_Overriding --
6629 -----------------------------------
6631 procedure Check_Synchronized_Overriding
6632 (Def_Id : Entity_Id;
6633 Overridden_Subp : out Entity_Id)
6635 Ifaces_List : Elist_Id;
6639 function Matches_Prefixed_View_Profile
6640 (Prim_Params : List_Id;
6641 Iface_Params : List_Id) return Boolean;
6642 -- Determine whether a subprogram's parameter profile Prim_Params
6643 -- matches that of a potentially overridden interface subprogram
6644 -- Iface_Params. Also determine if the type of first parameter of
6645 -- Iface_Params is an implemented interface.
6647 -----------------------------------
6648 -- Matches_Prefixed_View_Profile --
6649 -----------------------------------
6651 function Matches_Prefixed_View_Profile
6652 (Prim_Params : List_Id;
6653 Iface_Params : List_Id) return Boolean
6655 Iface_Id : Entity_Id;
6656 Iface_Param : Node_Id;
6657 Iface_Typ : Entity_Id;
6658 Prim_Id : Entity_Id;
6659 Prim_Param : Node_Id;
6660 Prim_Typ : Entity_Id;
6662 function Is_Implemented
6663 (Ifaces_List : Elist_Id;
6664 Iface : Entity_Id) return Boolean;
6665 -- Determine if Iface is implemented by the current task or
6668 --------------------
6669 -- Is_Implemented --
6670 --------------------
6672 function Is_Implemented
6673 (Ifaces_List : Elist_Id;
6674 Iface : Entity_Id) return Boolean
6676 Iface_Elmt : Elmt_Id;
6679 Iface_Elmt := First_Elmt (Ifaces_List);
6680 while Present (Iface_Elmt) loop
6681 if Node (Iface_Elmt) = Iface then
6685 Next_Elmt (Iface_Elmt);
6691 -- Start of processing for Matches_Prefixed_View_Profile
6694 Iface_Param := First (Iface_Params);
6695 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
6697 if Is_Access_Type (Iface_Typ) then
6698 Iface_Typ := Designated_Type (Iface_Typ);
6701 Prim_Param := First (Prim_Params);
6703 -- The first parameter of the potentially overridden subprogram
6704 -- must be an interface implemented by Prim.
6706 if not Is_Interface (Iface_Typ)
6707 or else not Is_Implemented (Ifaces_List, Iface_Typ)
6712 -- The checks on the object parameters are done, move onto the
6713 -- rest of the parameters.
6715 if not In_Scope then
6716 Prim_Param := Next (Prim_Param);
6719 Iface_Param := Next (Iface_Param);
6720 while Present (Iface_Param) and then Present (Prim_Param) loop
6721 Iface_Id := Defining_Identifier (Iface_Param);
6722 Iface_Typ := Find_Parameter_Type (Iface_Param);
6724 Prim_Id := Defining_Identifier (Prim_Param);
6725 Prim_Typ := Find_Parameter_Type (Prim_Param);
6727 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
6728 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
6729 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
6731 Iface_Typ := Designated_Type (Iface_Typ);
6732 Prim_Typ := Designated_Type (Prim_Typ);
6735 -- Case of multiple interface types inside a parameter profile
6737 -- (Obj_Param : in out Iface; ...; Param : Iface)
6739 -- If the interface type is implemented, then the matching type
6740 -- in the primitive should be the implementing record type.
6742 if Ekind (Iface_Typ) = E_Record_Type
6743 and then Is_Interface (Iface_Typ)
6744 and then Is_Implemented (Ifaces_List, Iface_Typ)
6746 if Prim_Typ /= Typ then
6750 -- The two parameters must be both mode and subtype conformant
6752 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
6754 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
6763 -- One of the two lists contains more parameters than the other
6765 if Present (Iface_Param) or else Present (Prim_Param) then
6770 end Matches_Prefixed_View_Profile;
6772 -- Start of processing for Check_Synchronized_Overriding
6775 Overridden_Subp := Empty;
6777 -- Def_Id must be an entry or a subprogram. We should skip predefined
6778 -- primitives internally generated by the frontend; however at this
6779 -- stage predefined primitives are still not fully decorated. As a
6780 -- minor optimization we skip here internally generated subprograms.
6782 if (Ekind (Def_Id) /= E_Entry
6783 and then Ekind (Def_Id) /= E_Function
6784 and then Ekind (Def_Id) /= E_Procedure)
6785 or else not Comes_From_Source (Def_Id)
6790 -- Search for the concurrent declaration since it contains the list
6791 -- of all implemented interfaces. In this case, the subprogram is
6792 -- declared within the scope of a protected or a task type.
6794 if Present (Scope (Def_Id))
6795 and then Is_Concurrent_Type (Scope (Def_Id))
6796 and then not Is_Generic_Actual_Type (Scope (Def_Id))
6798 Typ := Scope (Def_Id);
6801 -- The enclosing scope is not a synchronized type and the subprogram
6804 elsif No (First_Formal (Def_Id)) then
6807 -- The subprogram has formals and hence it may be a primitive of a
6811 Typ := Etype (First_Formal (Def_Id));
6813 if Is_Access_Type (Typ) then
6814 Typ := Directly_Designated_Type (Typ);
6817 if Is_Concurrent_Type (Typ)
6818 and then not Is_Generic_Actual_Type (Typ)
6822 -- This case occurs when the concurrent type is declared within
6823 -- a generic unit. As a result the corresponding record has been
6824 -- built and used as the type of the first formal, we just have
6825 -- to retrieve the corresponding concurrent type.
6827 elsif Is_Concurrent_Record_Type (Typ)
6828 and then Present (Corresponding_Concurrent_Type (Typ))
6830 Typ := Corresponding_Concurrent_Type (Typ);
6838 -- There is no overriding to check if is an inherited operation in a
6839 -- type derivation on for a generic actual.
6841 Collect_Interfaces (Typ, Ifaces_List);
6843 if Is_Empty_Elmt_List (Ifaces_List) then
6847 -- Determine whether entry or subprogram Def_Id overrides a primitive
6848 -- operation that belongs to one of the interfaces in Ifaces_List.
6851 Candidate : Entity_Id := Empty;
6852 Hom : Entity_Id := Empty;
6853 Iface_Typ : Entity_Id;
6854 Subp : Entity_Id := Empty;
6857 -- Traverse the homonym chain, looking at a potentially
6858 -- overridden subprogram that belongs to an implemented
6861 Hom := Current_Entity_In_Scope (Def_Id);
6862 while Present (Hom) loop
6866 or else not Is_Overloadable (Subp)
6867 or else not Is_Primitive (Subp)
6868 or else not Is_Dispatching_Operation (Subp)
6869 or else not Is_Interface (Find_Dispatching_Type (Subp))
6873 -- Entries and procedures can override abstract or null
6874 -- interface procedures
6876 elsif (Ekind (Def_Id) = E_Procedure
6877 or else Ekind (Def_Id) = E_Entry)
6878 and then Ekind (Subp) = E_Procedure
6879 and then Matches_Prefixed_View_Profile
6880 (Parameter_Specifications (Parent (Def_Id)),
6881 Parameter_Specifications (Parent (Subp)))
6885 -- For an overridden subprogram Subp, check whether the mode
6886 -- of its first parameter is correct depending on the kind
6887 -- of synchronized type.
6890 Formal : constant Node_Id := First_Formal (Candidate);
6893 -- In order for an entry or a protected procedure to
6894 -- override, the first parameter of the overridden
6895 -- routine must be of mode "out", "in out" or
6896 -- access-to-variable.
6898 if (Ekind (Candidate) = E_Entry
6899 or else Ekind (Candidate) = E_Procedure)
6900 and then Is_Protected_Type (Typ)
6901 and then Ekind (Formal) /= E_In_Out_Parameter
6902 and then Ekind (Formal) /= E_Out_Parameter
6903 and then Nkind (Parameter_Type (Parent (Formal)))
6904 /= N_Access_Definition
6908 -- All other cases are OK since a task entry or routine
6909 -- does not have a restriction on the mode of the first
6910 -- parameter of the overridden interface routine.
6913 Overridden_Subp := Candidate;
6918 -- Functions can override abstract interface functions
6920 elsif Ekind (Def_Id) = E_Function
6921 and then Ekind (Subp) = E_Function
6922 and then Matches_Prefixed_View_Profile
6923 (Parameter_Specifications (Parent (Def_Id)),
6924 Parameter_Specifications (Parent (Subp)))
6925 and then Etype (Result_Definition (Parent (Def_Id))) =
6926 Etype (Result_Definition (Parent (Subp)))
6928 Overridden_Subp := Subp;
6932 Hom := Homonym (Hom);
6935 -- After examining all candidates for overriding, we are
6936 -- left with the best match which is a mode incompatible
6937 -- interface routine. Do not emit an error if the Expander
6938 -- is active since this error will be detected later on
6939 -- after all concurrent types are expanded and all wrappers
6940 -- are built. This check is meant for spec-only
6943 if Present (Candidate)
6944 and then not Expander_Active
6947 Find_Parameter_Type (Parent (First_Formal (Candidate)));
6949 -- Def_Id is primitive of a protected type, declared
6950 -- inside the type, and the candidate is primitive of a
6951 -- limited or synchronized interface.
6954 and then Is_Protected_Type (Typ)
6956 (Is_Limited_Interface (Iface_Typ)
6957 or else Is_Protected_Interface (Iface_Typ)
6958 or else Is_Synchronized_Interface (Iface_Typ)
6959 or else Is_Task_Interface (Iface_Typ))
6961 -- Must reword this message, comma before to in -gnatj
6965 ("first formal of & must be of mode `OUT`, `IN OUT`"
6966 & " or access-to-variable", Typ, Candidate);
6968 ("\to be overridden by protected procedure or entry "
6969 & "(RM 9.4(11.9/2))", Typ);
6973 Overridden_Subp := Candidate;
6976 end Check_Synchronized_Overriding;
6978 ----------------------------
6979 -- Is_Private_Declaration --
6980 ----------------------------
6982 function Is_Private_Declaration (E : Entity_Id) return Boolean is
6983 Priv_Decls : List_Id;
6984 Decl : constant Node_Id := Unit_Declaration_Node (E);
6987 if Is_Package_Or_Generic_Package (Current_Scope)
6988 and then In_Private_Part (Current_Scope)
6991 Private_Declarations (
6992 Specification (Unit_Declaration_Node (Current_Scope)));
6994 return In_Package_Body (Current_Scope)
6996 (Is_List_Member (Decl)
6997 and then List_Containing (Decl) = Priv_Decls)
6998 or else (Nkind (Parent (Decl)) = N_Package_Specification
6999 and then not Is_Compilation_Unit (
7000 Defining_Entity (Parent (Decl)))
7001 and then List_Containing (Parent (Parent (Decl)))
7006 end Is_Private_Declaration;
7008 -- Start of processing for New_Overloaded_Entity
7011 -- We need to look for an entity that S may override. This must be a
7012 -- homonym in the current scope, so we look for the first homonym of
7013 -- S in the current scope as the starting point for the search.
7015 E := Current_Entity_In_Scope (S);
7017 -- If there is no homonym then this is definitely not overriding
7020 Enter_Overloaded_Entity (S);
7021 Check_Dispatching_Operation (S, Empty);
7022 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
7024 -- If subprogram has an explicit declaration, check whether it
7025 -- has an overriding indicator.
7027 if Comes_From_Source (S) then
7028 Check_Synchronized_Overriding (S, Overridden_Subp);
7029 Check_Overriding_Indicator
7030 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
7033 -- If there is a homonym that is not overloadable, then we have an
7034 -- error, except for the special cases checked explicitly below.
7036 elsif not Is_Overloadable (E) then
7038 -- Check for spurious conflict produced by a subprogram that has the
7039 -- same name as that of the enclosing generic package. The conflict
7040 -- occurs within an instance, between the subprogram and the renaming
7041 -- declaration for the package. After the subprogram, the package
7042 -- renaming declaration becomes hidden.
7044 if Ekind (E) = E_Package
7045 and then Present (Renamed_Object (E))
7046 and then Renamed_Object (E) = Current_Scope
7047 and then Nkind (Parent (Renamed_Object (E))) =
7048 N_Package_Specification
7049 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
7052 Set_Is_Immediately_Visible (E, False);
7053 Enter_Overloaded_Entity (S);
7054 Set_Homonym (S, Homonym (E));
7055 Check_Dispatching_Operation (S, Empty);
7056 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
7058 -- If the subprogram is implicit it is hidden by the previous
7059 -- declaration. However if it is dispatching, it must appear in the
7060 -- dispatch table anyway, because it can be dispatched to even if it
7061 -- cannot be called directly.
7063 elsif Present (Alias (S))
7064 and then not Comes_From_Source (S)
7066 Set_Scope (S, Current_Scope);
7068 if Is_Dispatching_Operation (Alias (S)) then
7069 Check_Dispatching_Operation (S, Empty);
7075 Error_Msg_Sloc := Sloc (E);
7077 -- Generate message, with useful additional warning if in generic
7079 if Is_Generic_Unit (E) then
7080 Error_Msg_N ("previous generic unit cannot be overloaded", S);
7081 Error_Msg_N ("\& conflicts with declaration#", S);
7083 Error_Msg_N ("& conflicts with declaration#", S);
7089 -- E exists and is overloadable
7092 -- Ada 2005 (AI-251): Derivation of abstract interface primitives
7093 -- need no check against the homonym chain. They are directly added
7094 -- to the list of primitive operations of Derived_Type.
7096 if Ada_Version >= Ada_05
7097 and then Present (Derived_Type)
7098 and then Is_Dispatching_Operation (Alias (S))
7099 and then Present (Find_Dispatching_Type (Alias (S)))
7100 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
7102 goto Add_New_Entity;
7105 Check_Synchronized_Overriding (S, Overridden_Subp);
7107 -- Loop through E and its homonyms to determine if any of them is
7108 -- the candidate for overriding by S.
7110 while Present (E) loop
7112 -- Definitely not interesting if not in the current scope
7114 if Scope (E) /= Current_Scope then
7117 -- Check if we have type conformance
7119 elsif Type_Conformant (E, S) then
7121 -- If the old and new entities have the same profile and one
7122 -- is not the body of the other, then this is an error, unless
7123 -- one of them is implicitly declared.
7125 -- There are some cases when both can be implicit, for example
7126 -- when both a literal and a function that overrides it are
7127 -- inherited in a derivation, or when an inherited operation
7128 -- of a tagged full type overrides the inherited operation of
7129 -- a private extension. Ada 83 had a special rule for the
7130 -- literal case. In Ada95, the later implicit operation hides
7131 -- the former, and the literal is always the former. In the
7132 -- odd case where both are derived operations declared at the
7133 -- same point, both operations should be declared, and in that
7134 -- case we bypass the following test and proceed to the next
7135 -- part (this can only occur for certain obscure cases
7136 -- involving homographs in instances and can't occur for
7137 -- dispatching operations ???). Note that the following
7138 -- condition is less than clear. For example, it's not at all
7139 -- clear why there's a test for E_Entry here. ???
7141 if Present (Alias (S))
7142 and then (No (Alias (E))
7143 or else Comes_From_Source (E)
7144 or else Is_Dispatching_Operation (E))
7146 (Ekind (E) = E_Entry
7147 or else Ekind (E) /= E_Enumeration_Literal)
7149 -- When an derived operation is overloaded it may be due to
7150 -- the fact that the full view of a private extension
7151 -- re-inherits. It has to be dealt with.
7153 if Is_Package_Or_Generic_Package (Current_Scope)
7154 and then In_Private_Part (Current_Scope)
7156 Check_Operation_From_Private_View (S, E);
7159 -- In any case the implicit operation remains hidden by
7160 -- the existing declaration, which is overriding.
7162 Set_Is_Overriding_Operation (E);
7164 if Comes_From_Source (E) then
7165 Check_Overriding_Indicator (E, S, Is_Primitive => False);
7167 -- Indicate that E overrides the operation from which
7170 if Present (Alias (S)) then
7171 Set_Overridden_Operation (E, Alias (S));
7173 Set_Overridden_Operation (E, S);
7179 -- Within an instance, the renaming declarations for
7180 -- actual subprograms may become ambiguous, but they do
7181 -- not hide each other.
7183 elsif Ekind (E) /= E_Entry
7184 and then not Comes_From_Source (E)
7185 and then not Is_Generic_Instance (E)
7186 and then (Present (Alias (E))
7187 or else Is_Intrinsic_Subprogram (E))
7188 and then (not In_Instance
7189 or else No (Parent (E))
7190 or else Nkind (Unit_Declaration_Node (E)) /=
7191 N_Subprogram_Renaming_Declaration)
7193 -- A subprogram child unit is not allowed to override
7194 -- an inherited subprogram (10.1.1(20)).
7196 if Is_Child_Unit (S) then
7198 ("child unit overrides inherited subprogram in parent",
7203 if Is_Non_Overriding_Operation (E, S) then
7204 Enter_Overloaded_Entity (S);
7205 if No (Derived_Type)
7206 or else Is_Tagged_Type (Derived_Type)
7208 Check_Dispatching_Operation (S, Empty);
7214 -- E is a derived operation or an internal operator which
7215 -- is being overridden. Remove E from further visibility.
7216 -- Furthermore, if E is a dispatching operation, it must be
7217 -- replaced in the list of primitive operations of its type
7218 -- (see Override_Dispatching_Operation).
7220 Overridden_Subp := E;
7226 Prev := First_Entity (Current_Scope);
7228 while Present (Prev)
7229 and then Next_Entity (Prev) /= E
7234 -- It is possible for E to be in the current scope and
7235 -- yet not in the entity chain. This can only occur in a
7236 -- generic context where E is an implicit concatenation
7237 -- in the formal part, because in a generic body the
7238 -- entity chain starts with the formals.
7241 (Present (Prev) or else Chars (E) = Name_Op_Concat);
7243 -- E must be removed both from the entity_list of the
7244 -- current scope, and from the visibility chain
7246 if Debug_Flag_E then
7247 Write_Str ("Override implicit operation ");
7248 Write_Int (Int (E));
7252 -- If E is a predefined concatenation, it stands for four
7253 -- different operations. As a result, a single explicit
7254 -- declaration does not hide it. In a possible ambiguous
7255 -- situation, Disambiguate chooses the user-defined op,
7256 -- so it is correct to retain the previous internal one.
7258 if Chars (E) /= Name_Op_Concat
7259 or else Ekind (E) /= E_Operator
7261 -- For nondispatching derived operations that are
7262 -- overridden by a subprogram declared in the private
7263 -- part of a package, we retain the derived
7264 -- subprogram but mark it as not immediately visible.
7265 -- If the derived operation was declared in the
7266 -- visible part then this ensures that it will still
7267 -- be visible outside the package with the proper
7268 -- signature (calls from outside must also be
7269 -- directed to this version rather than the
7270 -- overriding one, unlike the dispatching case).
7271 -- Calls from inside the package will still resolve
7272 -- to the overriding subprogram since the derived one
7273 -- is marked as not visible within the package.
7275 -- If the private operation is dispatching, we achieve
7276 -- the overriding by keeping the implicit operation
7277 -- but setting its alias to be the overriding one. In
7278 -- this fashion the proper body is executed in all
7279 -- cases, but the original signature is used outside
7282 -- If the overriding is not in the private part, we
7283 -- remove the implicit operation altogether.
7285 if Is_Private_Declaration (S) then
7287 if not Is_Dispatching_Operation (E) then
7288 Set_Is_Immediately_Visible (E, False);
7290 -- Work done in Override_Dispatching_Operation,
7291 -- so nothing else need to be done here.
7297 -- Find predecessor of E in Homonym chain
7299 if E = Current_Entity (E) then
7302 Prev_Vis := Current_Entity (E);
7303 while Homonym (Prev_Vis) /= E loop
7304 Prev_Vis := Homonym (Prev_Vis);
7308 if Prev_Vis /= Empty then
7310 -- Skip E in the visibility chain
7312 Set_Homonym (Prev_Vis, Homonym (E));
7315 Set_Name_Entity_Id (Chars (E), Homonym (E));
7318 Set_Next_Entity (Prev, Next_Entity (E));
7320 if No (Next_Entity (Prev)) then
7321 Set_Last_Entity (Current_Scope, Prev);
7327 Enter_Overloaded_Entity (S);
7328 Set_Is_Overriding_Operation (S);
7329 Check_Overriding_Indicator (S, E, Is_Primitive => True);
7331 -- Indicate that S overrides the operation from which
7334 if Comes_From_Source (S) then
7335 if Present (Alias (E)) then
7336 Set_Overridden_Operation (S, Alias (E));
7338 Set_Overridden_Operation (S, E);
7342 if Is_Dispatching_Operation (E) then
7344 -- An overriding dispatching subprogram inherits the
7345 -- convention of the overridden subprogram (by
7348 Set_Convention (S, Convention (E));
7349 Check_Dispatching_Operation (S, E);
7352 Check_Dispatching_Operation (S, Empty);
7355 Check_For_Primitive_Subprogram
7356 (Is_Primitive_Subp, Is_Overriding => True);
7357 goto Check_Inequality;
7360 -- Apparent redeclarations in instances can occur when two
7361 -- formal types get the same actual type. The subprograms in
7362 -- in the instance are legal, even if not callable from the
7363 -- outside. Calls from within are disambiguated elsewhere.
7364 -- For dispatching operations in the visible part, the usual
7365 -- rules apply, and operations with the same profile are not
7368 elsif (In_Instance_Visible_Part
7369 and then not Is_Dispatching_Operation (E))
7370 or else In_Instance_Not_Visible
7374 -- Here we have a real error (identical profile)
7377 Error_Msg_Sloc := Sloc (E);
7379 -- Avoid cascaded errors if the entity appears in
7380 -- subsequent calls.
7382 Set_Scope (S, Current_Scope);
7384 -- Generate error, with extra useful warning for the case
7385 -- of a generic instance with no completion.
7387 if Is_Generic_Instance (S)
7388 and then not Has_Completion (E)
7391 ("instantiation cannot provide body for&", S);
7392 Error_Msg_N ("\& conflicts with declaration#", S);
7394 Error_Msg_N ("& conflicts with declaration#", S);
7401 -- If one subprogram has an access parameter and the other
7402 -- a parameter of an access type, calls to either might be
7403 -- ambiguous. Verify that parameters match except for the
7404 -- access parameter.
7406 if May_Hide_Profile then
7411 F1 := First_Formal (S);
7412 F2 := First_Formal (E);
7413 while Present (F1) and then Present (F2) loop
7414 if Is_Access_Type (Etype (F1)) then
7415 if not Is_Access_Type (Etype (F2))
7416 or else not Conforming_Types
7417 (Designated_Type (Etype (F1)),
7418 Designated_Type (Etype (F2)),
7421 May_Hide_Profile := False;
7425 not Conforming_Types
7426 (Etype (F1), Etype (F2), Type_Conformant)
7428 May_Hide_Profile := False;
7439 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
7450 -- On exit, we know that S is a new entity
7452 Enter_Overloaded_Entity (S);
7453 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
7454 Check_Overriding_Indicator
7455 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
7457 -- If S is a derived operation for an untagged type then by
7458 -- definition it's not a dispatching operation (even if the parent
7459 -- operation was dispatching), so we don't call
7460 -- Check_Dispatching_Operation in that case.
7462 if No (Derived_Type)
7463 or else Is_Tagged_Type (Derived_Type)
7465 Check_Dispatching_Operation (S, Empty);
7469 -- If this is a user-defined equality operator that is not a derived
7470 -- subprogram, create the corresponding inequality. If the operation is
7471 -- dispatching, the expansion is done elsewhere, and we do not create
7472 -- an explicit inequality operation.
7474 <<Check_Inequality>>
7475 if Chars (S) = Name_Op_Eq
7476 and then Etype (S) = Standard_Boolean
7477 and then Present (Parent (S))
7478 and then not Is_Dispatching_Operation (S)
7480 Make_Inequality_Operator (S);
7482 end New_Overloaded_Entity;
7484 ---------------------
7485 -- Process_Formals --
7486 ---------------------
7488 procedure Process_Formals
7490 Related_Nod : Node_Id)
7492 Param_Spec : Node_Id;
7494 Formal_Type : Entity_Id;
7498 Num_Out_Params : Nat := 0;
7499 First_Out_Param : Entity_Id := Empty;
7500 -- Used for setting Is_Only_Out_Parameter
7502 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
7503 -- Check whether the default has a class-wide type. After analysis the
7504 -- default has the type of the formal, so we must also check explicitly
7505 -- for an access attribute.
7507 ---------------------------
7508 -- Is_Class_Wide_Default --
7509 ---------------------------
7511 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
7513 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
7514 or else (Nkind (D) = N_Attribute_Reference
7515 and then Attribute_Name (D) = Name_Access
7516 and then Is_Class_Wide_Type (Etype (Prefix (D))));
7517 end Is_Class_Wide_Default;
7519 -- Start of processing for Process_Formals
7522 -- In order to prevent premature use of the formals in the same formal
7523 -- part, the Ekind is left undefined until all default expressions are
7524 -- analyzed. The Ekind is established in a separate loop at the end.
7526 Param_Spec := First (T);
7527 while Present (Param_Spec) loop
7528 Formal := Defining_Identifier (Param_Spec);
7529 Set_Never_Set_In_Source (Formal, True);
7530 Enter_Name (Formal);
7532 -- Case of ordinary parameters
7534 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
7535 Find_Type (Parameter_Type (Param_Spec));
7536 Ptype := Parameter_Type (Param_Spec);
7538 if Ptype = Error then
7542 Formal_Type := Entity (Ptype);
7544 if Is_Incomplete_Type (Formal_Type)
7546 (Is_Class_Wide_Type (Formal_Type)
7547 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
7549 -- Ada 2005 (AI-326): Tagged incomplete types allowed
7551 if Is_Tagged_Type (Formal_Type) then
7554 -- Special handling of Value_Type for CIL case
7556 elsif Is_Value_Type (Formal_Type) then
7559 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
7560 N_Access_Procedure_Definition)
7562 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
7564 -- An incomplete type that is not tagged is allowed in an
7565 -- access-to-subprogram type only if it is a local declaration
7566 -- with a forthcoming completion (3.10.1 (9.2/2)).
7568 elsif Scope (Formal_Type) /= Scope (Current_Scope) then
7570 ("invalid use of limited view of type", Param_Spec);
7573 elsif Ekind (Formal_Type) = E_Void then
7574 Error_Msg_NE ("premature use of&",
7575 Parameter_Type (Param_Spec), Formal_Type);
7578 -- Ada 2005 (AI-231): Create and decorate an internal subtype
7579 -- declaration corresponding to the null-excluding type of the
7580 -- formal in the enclosing scope. Finally, replace the parameter
7581 -- type of the formal with the internal subtype.
7583 if Ada_Version >= Ada_05
7584 and then Null_Exclusion_Present (Param_Spec)
7586 if not Is_Access_Type (Formal_Type) then
7588 ("`NOT NULL` allowed only for an access type", Param_Spec);
7591 if Can_Never_Be_Null (Formal_Type)
7592 and then Comes_From_Source (Related_Nod)
7595 ("`NOT NULL` not allowed (& already excludes null)",
7601 Create_Null_Excluding_Itype
7603 Related_Nod => Related_Nod,
7604 Scope_Id => Scope (Current_Scope));
7606 -- If the designated type of the itype is an itype we
7607 -- decorate it with the Has_Delayed_Freeze attribute to
7608 -- avoid problems with the backend.
7611 -- type T is access procedure;
7612 -- procedure Op (O : not null T);
7614 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
7615 Set_Has_Delayed_Freeze (Formal_Type);
7620 -- An access formal type
7624 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
7626 -- No need to continue if we already notified errors
7628 if not Present (Formal_Type) then
7632 -- Ada 2005 (AI-254)
7635 AD : constant Node_Id :=
7636 Access_To_Subprogram_Definition
7637 (Parameter_Type (Param_Spec));
7639 if Present (AD) and then Protected_Present (AD) then
7641 Replace_Anonymous_Access_To_Protected_Subprogram
7647 Set_Etype (Formal, Formal_Type);
7648 Default := Expression (Param_Spec);
7650 if Present (Default) then
7651 if Out_Present (Param_Spec) then
7653 ("default initialization only allowed for IN parameters",
7657 -- Do the special preanalysis of the expression (see section on
7658 -- "Handling of Default Expressions" in the spec of package Sem).
7660 Preanalyze_Spec_Expression (Default, Formal_Type);
7662 -- An access to constant cannot be the default for
7663 -- an access parameter that is an access to variable.
7665 if Ekind (Formal_Type) = E_Anonymous_Access_Type
7666 and then not Is_Access_Constant (Formal_Type)
7667 and then Is_Access_Type (Etype (Default))
7668 and then Is_Access_Constant (Etype (Default))
7671 ("formal that is access to variable cannot be initialized " &
7672 "with an access-to-constant expression", Default);
7675 -- Check that the designated type of an access parameter's default
7676 -- is not a class-wide type unless the parameter's designated type
7677 -- is also class-wide.
7679 if Ekind (Formal_Type) = E_Anonymous_Access_Type
7680 and then not From_With_Type (Formal_Type)
7681 and then Is_Class_Wide_Default (Default)
7682 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
7685 ("access to class-wide expression not allowed here", Default);
7689 -- Ada 2005 (AI-231): Static checks
7691 if Ada_Version >= Ada_05
7692 and then Is_Access_Type (Etype (Formal))
7693 and then Can_Never_Be_Null (Etype (Formal))
7695 Null_Exclusion_Static_Checks (Param_Spec);
7702 -- If this is the formal part of a function specification, analyze the
7703 -- subtype mark in the context where the formals are visible but not
7704 -- yet usable, and may hide outer homographs.
7706 if Nkind (Related_Nod) = N_Function_Specification then
7707 Analyze_Return_Type (Related_Nod);
7710 -- Now set the kind (mode) of each formal
7712 Param_Spec := First (T);
7714 while Present (Param_Spec) loop
7715 Formal := Defining_Identifier (Param_Spec);
7716 Set_Formal_Mode (Formal);
7718 if Ekind (Formal) = E_In_Parameter then
7719 Set_Default_Value (Formal, Expression (Param_Spec));
7721 if Present (Expression (Param_Spec)) then
7722 Default := Expression (Param_Spec);
7724 if Is_Scalar_Type (Etype (Default)) then
7726 (Parameter_Type (Param_Spec)) /= N_Access_Definition
7728 Formal_Type := Entity (Parameter_Type (Param_Spec));
7731 Formal_Type := Access_Definition
7732 (Related_Nod, Parameter_Type (Param_Spec));
7735 Apply_Scalar_Range_Check (Default, Formal_Type);
7739 elsif Ekind (Formal) = E_Out_Parameter then
7740 Num_Out_Params := Num_Out_Params + 1;
7742 if Num_Out_Params = 1 then
7743 First_Out_Param := Formal;
7746 elsif Ekind (Formal) = E_In_Out_Parameter then
7747 Num_Out_Params := Num_Out_Params + 1;
7753 if Present (First_Out_Param) and then Num_Out_Params = 1 then
7754 Set_Is_Only_Out_Parameter (First_Out_Param);
7756 end Process_Formals;
7762 procedure Process_PPCs
7764 Spec_Id : Entity_Id;
7765 Body_Id : Entity_Id)
7767 Loc : constant Source_Ptr := Sloc (N);
7769 Plist : List_Id := No_List;
7773 function Grab_PPC (Nam : Name_Id) return Node_Id;
7774 -- Prag contains an analyzed precondition or postcondition pragma.
7775 -- This function copies the pragma, changes it to the corresponding
7776 -- Check pragma and returns the Check pragma as the result. The
7777 -- argument Nam is either Name_Precondition or Name_Postcondition.
7783 function Grab_PPC (Nam : Name_Id) return Node_Id is
7784 CP : constant Node_Id := New_Copy_Tree (Prag);
7787 -- Set Analyzed to false, since we want to reanalyze the check
7788 -- procedure. Note that it is only at the outer level that we
7789 -- do this fiddling, for the spec cases, the already preanalyzed
7790 -- parameters are not affected.
7792 -- For a postcondition pragma within a generic, preserve the pragma
7793 -- for later expansion.
7795 Set_Analyzed (CP, False);
7797 if Nam = Name_Postcondition
7798 and then not Expander_Active
7803 -- Change pragma into corresponding pragma Check
7805 Prepend_To (Pragma_Argument_Associations (CP),
7806 Make_Pragma_Argument_Association (Sloc (Prag),
7808 Make_Identifier (Loc,
7810 Set_Pragma_Identifier (CP,
7811 Make_Identifier (Sloc (Prag),
7812 Chars => Name_Check));
7817 -- Start of processing for Process_PPCs
7820 -- Nothing to do if we are not generating code
7822 if Operating_Mode /= Generate_Code then
7826 -- Grab preconditions from spec
7828 if Present (Spec_Id) then
7830 -- Loop through PPC pragmas from spec. Note that preconditions from
7831 -- the body will be analyzed and converted when we scan the body
7832 -- declarations below.
7834 Prag := Spec_PPC_List (Spec_Id);
7835 while Present (Prag) loop
7836 if Pragma_Name (Prag) = Name_Precondition
7837 and then PPC_Enabled (Prag)
7839 -- Add pragma Check at the start of the declarations of N.
7840 -- Note that this processing reverses the order of the list,
7841 -- which is what we want since new entries were chained to
7842 -- the head of the list.
7844 Prepend (Grab_PPC (Name_Precondition), Declarations (N));
7847 Prag := Next_Pragma (Prag);
7851 -- Build postconditions procedure if needed and prepend the following
7852 -- declaration to the start of the declarations for the subprogram.
7854 -- procedure _postconditions [(_Result : resulttype)] is
7856 -- pragma Check (Postcondition, condition [,message]);
7857 -- pragma Check (Postcondition, condition [,message]);
7861 -- First we deal with the postconditions in the body
7863 if Is_Non_Empty_List (Declarations (N)) then
7865 -- Loop through declarations
7867 Prag := First (Declarations (N));
7868 while Present (Prag) loop
7869 if Nkind (Prag) = N_Pragma then
7871 -- If pragma, capture if enabled postcondition, else ignore
7873 if Pragma_Name (Prag) = Name_Postcondition
7874 and then Check_Enabled (Name_Postcondition)
7876 if Plist = No_List then
7877 Plist := Empty_List;
7882 -- If expansion is disabled, as in a generic unit,
7883 -- save pragma for later expansion.
7885 if not Expander_Active then
7886 Prepend (Grab_PPC (Name_Postcondition), Declarations (N));
7888 Append (Grab_PPC (Name_Postcondition), Plist);
7894 -- Not a pragma, if comes from source, then end scan
7896 elsif Comes_From_Source (Prag) then
7899 -- Skip stuff not coming from source
7907 -- Now deal with any postconditions from the spec
7909 if Present (Spec_Id) then
7911 -- Loop through PPC pragmas from spec
7913 Prag := Spec_PPC_List (Spec_Id);
7914 while Present (Prag) loop
7915 if Pragma_Name (Prag) = Name_Postcondition
7916 and then PPC_Enabled (Prag)
7918 if Plist = No_List then
7919 Plist := Empty_List;
7922 if not Expander_Active then
7923 Prepend (Grab_PPC (Name_Postcondition), Declarations (N));
7925 Append (Grab_PPC (Name_Postcondition), Plist);
7929 Prag := Next_Pragma (Prag);
7933 -- If we had any postconditions and expansion is enabled, build
7934 -- the Postconditions procedure.
7937 and then Expander_Active
7939 Subp := Defining_Entity (N);
7941 if Etype (Subp) /= Standard_Void_Type then
7943 Make_Parameter_Specification (Loc,
7944 Defining_Identifier =>
7945 Make_Defining_Identifier (Loc,
7946 Chars => Name_uResult),
7947 Parameter_Type => New_Occurrence_Of (Etype (Subp), Loc)));
7952 Prepend_To (Declarations (N),
7953 Make_Subprogram_Body (Loc,
7955 Make_Procedure_Specification (Loc,
7956 Defining_Unit_Name =>
7957 Make_Defining_Identifier (Loc,
7958 Chars => Name_uPostconditions),
7959 Parameter_Specifications => Parms),
7961 Declarations => Empty_List,
7963 Handled_Statement_Sequence =>
7964 Make_Handled_Sequence_Of_Statements (Loc,
7965 Statements => Plist)));
7967 if Present (Spec_Id) then
7968 Set_Has_Postconditions (Spec_Id);
7970 Set_Has_Postconditions (Body_Id);
7975 ----------------------------
7976 -- Reference_Body_Formals --
7977 ----------------------------
7979 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
7984 if Error_Posted (Spec) then
7988 -- Iterate over both lists. They may be of different lengths if the two
7989 -- specs are not conformant.
7991 Fs := First_Formal (Spec);
7992 Fb := First_Formal (Bod);
7993 while Present (Fs) and then Present (Fb) loop
7994 Generate_Reference (Fs, Fb, 'b');
7997 Style.Check_Identifier (Fb, Fs);
8000 Set_Spec_Entity (Fb, Fs);
8001 Set_Referenced (Fs, False);
8005 end Reference_Body_Formals;
8007 -------------------------
8008 -- Set_Actual_Subtypes --
8009 -------------------------
8011 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
8012 Loc : constant Source_Ptr := Sloc (N);
8016 First_Stmt : Node_Id := Empty;
8017 AS_Needed : Boolean;
8020 -- If this is an empty initialization procedure, no need to create
8021 -- actual subtypes (small optimization).
8023 if Ekind (Subp) = E_Procedure
8024 and then Is_Null_Init_Proc (Subp)
8029 Formal := First_Formal (Subp);
8030 while Present (Formal) loop
8031 T := Etype (Formal);
8033 -- We never need an actual subtype for a constrained formal
8035 if Is_Constrained (T) then
8038 -- If we have unknown discriminants, then we do not need an actual
8039 -- subtype, or more accurately we cannot figure it out! Note that
8040 -- all class-wide types have unknown discriminants.
8042 elsif Has_Unknown_Discriminants (T) then
8045 -- At this stage we have an unconstrained type that may need an
8046 -- actual subtype. For sure the actual subtype is needed if we have
8047 -- an unconstrained array type.
8049 elsif Is_Array_Type (T) then
8052 -- The only other case needing an actual subtype is an unconstrained
8053 -- record type which is an IN parameter (we cannot generate actual
8054 -- subtypes for the OUT or IN OUT case, since an assignment can
8055 -- change the discriminant values. However we exclude the case of
8056 -- initialization procedures, since discriminants are handled very
8057 -- specially in this context, see the section entitled "Handling of
8058 -- Discriminants" in Einfo.
8060 -- We also exclude the case of Discrim_SO_Functions (functions used
8061 -- in front end layout mode for size/offset values), since in such
8062 -- functions only discriminants are referenced, and not only are such
8063 -- subtypes not needed, but they cannot always be generated, because
8064 -- of order of elaboration issues.
8066 elsif Is_Record_Type (T)
8067 and then Ekind (Formal) = E_In_Parameter
8068 and then Chars (Formal) /= Name_uInit
8069 and then not Is_Unchecked_Union (T)
8070 and then not Is_Discrim_SO_Function (Subp)
8074 -- All other cases do not need an actual subtype
8080 -- Generate actual subtypes for unconstrained arrays and
8081 -- unconstrained discriminated records.
8084 if Nkind (N) = N_Accept_Statement then
8086 -- If expansion is active, The formal is replaced by a local
8087 -- variable that renames the corresponding entry of the
8088 -- parameter block, and it is this local variable that may
8089 -- require an actual subtype.
8091 if Expander_Active then
8092 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
8094 Decl := Build_Actual_Subtype (T, Formal);
8097 if Present (Handled_Statement_Sequence (N)) then
8099 First (Statements (Handled_Statement_Sequence (N)));
8100 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
8101 Mark_Rewrite_Insertion (Decl);
8103 -- If the accept statement has no body, there will be no
8104 -- reference to the actuals, so no need to compute actual
8111 Decl := Build_Actual_Subtype (T, Formal);
8112 Prepend (Decl, Declarations (N));
8113 Mark_Rewrite_Insertion (Decl);
8116 -- The declaration uses the bounds of an existing object, and
8117 -- therefore needs no constraint checks.
8119 Analyze (Decl, Suppress => All_Checks);
8121 -- We need to freeze manually the generated type when it is
8122 -- inserted anywhere else than in a declarative part.
8124 if Present (First_Stmt) then
8125 Insert_List_Before_And_Analyze (First_Stmt,
8126 Freeze_Entity (Defining_Identifier (Decl), Loc));
8129 if Nkind (N) = N_Accept_Statement
8130 and then Expander_Active
8132 Set_Actual_Subtype (Renamed_Object (Formal),
8133 Defining_Identifier (Decl));
8135 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
8139 Next_Formal (Formal);
8141 end Set_Actual_Subtypes;
8143 ---------------------
8144 -- Set_Formal_Mode --
8145 ---------------------
8147 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
8148 Spec : constant Node_Id := Parent (Formal_Id);
8151 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
8152 -- since we ensure that corresponding actuals are always valid at the
8153 -- point of the call.
8155 if Out_Present (Spec) then
8156 if Ekind (Scope (Formal_Id)) = E_Function
8157 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
8159 Error_Msg_N ("functions can only have IN parameters", Spec);
8160 Set_Ekind (Formal_Id, E_In_Parameter);
8162 elsif In_Present (Spec) then
8163 Set_Ekind (Formal_Id, E_In_Out_Parameter);
8166 Set_Ekind (Formal_Id, E_Out_Parameter);
8167 Set_Never_Set_In_Source (Formal_Id, True);
8168 Set_Is_True_Constant (Formal_Id, False);
8169 Set_Current_Value (Formal_Id, Empty);
8173 Set_Ekind (Formal_Id, E_In_Parameter);
8176 -- Set Is_Known_Non_Null for access parameters since the language
8177 -- guarantees that access parameters are always non-null. We also set
8178 -- Can_Never_Be_Null, since there is no way to change the value.
8180 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
8182 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
8183 -- null; In Ada 2005, only if then null_exclusion is explicit.
8185 if Ada_Version < Ada_05
8186 or else Can_Never_Be_Null (Etype (Formal_Id))
8188 Set_Is_Known_Non_Null (Formal_Id);
8189 Set_Can_Never_Be_Null (Formal_Id);
8192 -- Ada 2005 (AI-231): Null-exclusion access subtype
8194 elsif Is_Access_Type (Etype (Formal_Id))
8195 and then Can_Never_Be_Null (Etype (Formal_Id))
8197 Set_Is_Known_Non_Null (Formal_Id);
8200 Set_Mechanism (Formal_Id, Default_Mechanism);
8201 Set_Formal_Validity (Formal_Id);
8202 end Set_Formal_Mode;
8204 -------------------------
8205 -- Set_Formal_Validity --
8206 -------------------------
8208 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
8210 -- If no validity checking, then we cannot assume anything about the
8211 -- validity of parameters, since we do not know there is any checking
8212 -- of the validity on the call side.
8214 if not Validity_Checks_On then
8217 -- If validity checking for parameters is enabled, this means we are
8218 -- not supposed to make any assumptions about argument values.
8220 elsif Validity_Check_Parameters then
8223 -- If we are checking in parameters, we will assume that the caller is
8224 -- also checking parameters, so we can assume the parameter is valid.
8226 elsif Ekind (Formal_Id) = E_In_Parameter
8227 and then Validity_Check_In_Params
8229 Set_Is_Known_Valid (Formal_Id, True);
8231 -- Similar treatment for IN OUT parameters
8233 elsif Ekind (Formal_Id) = E_In_Out_Parameter
8234 and then Validity_Check_In_Out_Params
8236 Set_Is_Known_Valid (Formal_Id, True);
8238 end Set_Formal_Validity;
8240 ------------------------
8241 -- Subtype_Conformant --
8242 ------------------------
8244 function Subtype_Conformant
8245 (New_Id : Entity_Id;
8247 Skip_Controlling_Formals : Boolean := False) return Boolean
8251 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
8252 Skip_Controlling_Formals => Skip_Controlling_Formals);
8254 end Subtype_Conformant;
8256 ---------------------
8257 -- Type_Conformant --
8258 ---------------------
8260 function Type_Conformant
8261 (New_Id : Entity_Id;
8263 Skip_Controlling_Formals : Boolean := False) return Boolean
8267 May_Hide_Profile := False;
8270 (New_Id, Old_Id, Type_Conformant, False, Result,
8271 Skip_Controlling_Formals => Skip_Controlling_Formals);
8273 end Type_Conformant;
8275 -------------------------------
8276 -- Valid_Operator_Definition --
8277 -------------------------------
8279 procedure Valid_Operator_Definition (Designator : Entity_Id) is
8282 Id : constant Name_Id := Chars (Designator);
8286 F := First_Formal (Designator);
8287 while Present (F) loop
8290 if Present (Default_Value (F)) then
8292 ("default values not allowed for operator parameters",
8299 -- Verify that user-defined operators have proper number of arguments
8300 -- First case of operators which can only be unary
8303 or else Id = Name_Op_Abs
8307 -- Case of operators which can be unary or binary
8309 elsif Id = Name_Op_Add
8310 or Id = Name_Op_Subtract
8312 N_OK := (N in 1 .. 2);
8314 -- All other operators can only be binary
8322 ("incorrect number of arguments for operator", Designator);
8326 and then Base_Type (Etype (Designator)) = Standard_Boolean
8327 and then not Is_Intrinsic_Subprogram (Designator)
8330 ("explicit definition of inequality not allowed", Designator);
8332 end Valid_Operator_Definition;