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_Tss; use Exp_Tss;
37 with Exp_Util; use Exp_Util;
38 with Fname; use Fname;
39 with Freeze; use Freeze;
40 with Itypes; use Itypes;
41 with Lib.Xref; use Lib.Xref;
42 with Layout; use Layout;
43 with Namet; use Namet;
45 with Nlists; use Nlists;
46 with Nmake; use Nmake;
48 with Output; use Output;
49 with Rtsfind; use Rtsfind;
51 with Sem_Cat; use Sem_Cat;
52 with Sem_Ch3; use Sem_Ch3;
53 with Sem_Ch4; use Sem_Ch4;
54 with Sem_Ch5; use Sem_Ch5;
55 with Sem_Ch8; use Sem_Ch8;
56 with Sem_Ch10; use Sem_Ch10;
57 with Sem_Ch12; use Sem_Ch12;
58 with Sem_Disp; use Sem_Disp;
59 with Sem_Dist; use Sem_Dist;
60 with Sem_Elim; use Sem_Elim;
61 with Sem_Eval; use Sem_Eval;
62 with Sem_Mech; use Sem_Mech;
63 with Sem_Prag; use Sem_Prag;
64 with Sem_Res; use Sem_Res;
65 with Sem_Util; use Sem_Util;
66 with Sem_Type; use Sem_Type;
67 with Sem_Warn; use Sem_Warn;
68 with Sinput; use Sinput;
69 with Stand; use Stand;
70 with Sinfo; use Sinfo;
71 with Sinfo.CN; use Sinfo.CN;
72 with Snames; use Snames;
73 with Stringt; use Stringt;
75 with Stylesw; use Stylesw;
76 with Tbuild; use Tbuild;
77 with Uintp; use Uintp;
78 with Urealp; use Urealp;
79 with Validsw; use Validsw;
81 package body Sem_Ch6 is
83 May_Hide_Profile : Boolean := False;
84 -- This flag is used to indicate that two formals in two subprograms being
85 -- checked for conformance differ only in that one is an access parameter
86 -- while the other is of a general access type with the same designated
87 -- type. In this case, if the rest of the signatures match, a call to
88 -- either subprogram may be ambiguous, which is worth a warning. The flag
89 -- is set in Compatible_Types, and the warning emitted in
90 -- New_Overloaded_Entity.
92 -----------------------
93 -- Local Subprograms --
94 -----------------------
96 procedure Analyze_Return_Statement (N : Node_Id);
97 -- Common processing for simple_ and extended_return_statements
99 procedure Analyze_Function_Return (N : Node_Id);
100 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
101 -- applies to a [generic] function.
103 procedure Analyze_Return_Type (N : Node_Id);
104 -- Subsidiary to Process_Formals: analyze subtype mark in function
105 -- specification, in a context where the formals are visible and hide
108 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
109 -- Analyze a generic subprogram body. N is the body to be analyzed, and
110 -- Gen_Id is the defining entity Id for the corresponding spec.
112 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
113 -- If a subprogram has pragma Inline and inlining is active, use generic
114 -- machinery to build an unexpanded body for the subprogram. This body is
115 -- subsequently used for inline expansions at call sites. If subprogram can
116 -- be inlined (depending on size and nature of local declarations) this
117 -- function returns true. Otherwise subprogram body is treated normally.
118 -- If proper warnings are enabled and the subprogram contains a construct
119 -- that cannot be inlined, the offending construct is flagged accordingly.
121 procedure Check_Conformance
124 Ctype : Conformance_Type;
126 Conforms : out Boolean;
127 Err_Loc : Node_Id := Empty;
128 Get_Inst : Boolean := False;
129 Skip_Controlling_Formals : Boolean := False);
130 -- Given two entities, this procedure checks that the profiles associated
131 -- with these entities meet the conformance criterion given by the third
132 -- parameter. If they conform, Conforms is set True and control returns
133 -- to the caller. If they do not conform, Conforms is set to False, and
134 -- in addition, if Errmsg is True on the call, proper messages are output
135 -- to complain about the conformance failure. If Err_Loc is non_Empty
136 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
137 -- error messages are placed on the appropriate part of the construct
138 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
139 -- against a formal access-to-subprogram type so Get_Instance_Of must
142 procedure Check_Subprogram_Order (N : Node_Id);
143 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
144 -- the alpha ordering rule for N if this ordering requirement applicable.
146 procedure Check_Returns
150 Proc : Entity_Id := Empty);
151 -- Called to check for missing return statements in a function body, or for
152 -- returns present in a procedure body which has No_Return set. HSS is the
153 -- handled statement sequence for the subprogram body. This procedure
154 -- checks all flow paths to make sure they either have return (Mode = 'F',
155 -- used for functions) or do not have a return (Mode = 'P', used for
156 -- No_Return procedures). The flag Err is set if there are any control
157 -- paths not explicitly terminated by a return in the function case, and is
158 -- True otherwise. Proc is the entity for the procedure case and is used
159 -- in posting the warning message.
161 procedure Enter_Overloaded_Entity (S : Entity_Id);
162 -- This procedure makes S, a new overloaded entity, into the first visible
163 -- entity with that name.
165 procedure Install_Entity (E : Entity_Id);
166 -- Make single entity visible. Used for generic formals as well
168 function Is_Non_Overriding_Operation
170 New_E : Entity_Id) return Boolean;
171 -- Enforce the rule given in 12.3(18): a private operation in an instance
172 -- overrides an inherited operation only if the corresponding operation
173 -- was overriding in the generic. This can happen for primitive operations
174 -- of types derived (in the generic unit) from formal private or formal
177 procedure Make_Inequality_Operator (S : Entity_Id);
178 -- Create the declaration for an inequality operator that is implicitly
179 -- created by a user-defined equality operator that yields a boolean.
181 procedure May_Need_Actuals (Fun : Entity_Id);
182 -- Flag functions that can be called without parameters, i.e. those that
183 -- have no parameters, or those for which defaults exist for all parameters
185 procedure Process_PPCs
188 Body_Id : Entity_Id);
189 -- Called from Analyze_Body to deal with scanning post conditions for the
190 -- body and assembling and inserting the _postconditions procedure. N is
191 -- the node for the subprogram body and Body_Id/Spec_Id are the entities
192 -- for the body and separate spec (if there is no separate spec, Spec_Id
195 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
196 -- Formal_Id is an formal parameter entity. This procedure deals with
197 -- setting the proper validity status for this entity, which depends
198 -- on the kind of parameter and the validity checking mode.
200 ------------------------------
201 -- Analyze_Return_Statement --
202 ------------------------------
204 procedure Analyze_Return_Statement (N : Node_Id) is
206 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
207 N_Extended_Return_Statement));
209 Returns_Object : constant Boolean :=
210 Nkind (N) = N_Extended_Return_Statement
212 (Nkind (N) = N_Simple_Return_Statement
213 and then Present (Expression (N)));
214 -- True if we're returning something; that is, "return <expression>;"
215 -- or "return Result : T [:= ...]". False for "return;". Used for error
216 -- checking: If Returns_Object is True, N should apply to a function
217 -- body; otherwise N should apply to a procedure body, entry body,
218 -- accept statement, or extended return statement.
220 function Find_What_It_Applies_To return Entity_Id;
221 -- Find the entity representing the innermost enclosing body, accept
222 -- statement, or extended return statement. If the result is a callable
223 -- construct or extended return statement, then this will be the value
224 -- of the Return_Applies_To attribute. Otherwise, the program is
225 -- illegal. See RM-6.5(4/2).
227 -----------------------------
228 -- Find_What_It_Applies_To --
229 -----------------------------
231 function Find_What_It_Applies_To return Entity_Id is
232 Result : Entity_Id := Empty;
235 -- Loop outward through the Scope_Stack, skipping blocks and loops
237 for J in reverse 0 .. Scope_Stack.Last loop
238 Result := Scope_Stack.Table (J).Entity;
239 exit when Ekind (Result) /= E_Block and then
240 Ekind (Result) /= E_Loop;
243 pragma Assert (Present (Result));
245 end Find_What_It_Applies_To;
247 -- Local declarations
249 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
250 Kind : constant Entity_Kind := Ekind (Scope_Id);
251 Loc : constant Source_Ptr := Sloc (N);
252 Stm_Entity : constant Entity_Id :=
254 (E_Return_Statement, Current_Scope, Loc, 'R');
256 -- Start of processing for Analyze_Return_Statement
259 Set_Return_Statement_Entity (N, Stm_Entity);
261 Set_Etype (Stm_Entity, Standard_Void_Type);
262 Set_Return_Applies_To (Stm_Entity, Scope_Id);
264 -- Place Return entity on scope stack, to simplify enforcement of 6.5
265 -- (4/2): an inner return statement will apply to this extended return.
267 if Nkind (N) = N_Extended_Return_Statement then
268 Push_Scope (Stm_Entity);
271 -- Check that pragma No_Return is obeyed
273 if No_Return (Scope_Id) then
274 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
277 -- Warn on any unassigned OUT parameters if in procedure
279 if Ekind (Scope_Id) = E_Procedure then
280 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
283 -- Check that functions return objects, and other things do not
285 if Kind = E_Function or else Kind = E_Generic_Function then
286 if not Returns_Object then
287 Error_Msg_N ("missing expression in return from function", N);
290 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
291 if Returns_Object then
292 Error_Msg_N ("procedure cannot return value (use function)", N);
295 elsif Kind = E_Entry or else Kind = E_Entry_Family then
296 if Returns_Object then
297 if Is_Protected_Type (Scope (Scope_Id)) then
298 Error_Msg_N ("entry body cannot return value", N);
300 Error_Msg_N ("accept statement cannot return value", N);
304 elsif Kind = E_Return_Statement then
306 -- We are nested within another return statement, which must be an
307 -- extended_return_statement.
309 if Returns_Object then
311 ("extended_return_statement cannot return value; " &
312 "use `""RETURN;""`", N);
316 Error_Msg_N ("illegal context for return statement", N);
319 if Kind = E_Function or else Kind = E_Generic_Function then
320 Analyze_Function_Return (N);
323 if Nkind (N) = N_Extended_Return_Statement then
327 Kill_Current_Values (Last_Assignment_Only => True);
328 Check_Unreachable_Code (N);
329 end Analyze_Return_Statement;
331 ---------------------------------------------
332 -- Analyze_Abstract_Subprogram_Declaration --
333 ---------------------------------------------
335 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
336 Designator : constant Entity_Id :=
337 Analyze_Subprogram_Specification (Specification (N));
338 Scop : constant Entity_Id := Current_Scope;
341 Generate_Definition (Designator);
342 Set_Is_Abstract_Subprogram (Designator);
343 New_Overloaded_Entity (Designator);
344 Check_Delayed_Subprogram (Designator);
346 Set_Categorization_From_Scope (Designator, Scop);
348 if Ekind (Scope (Designator)) = E_Protected_Type then
350 ("abstract subprogram not allowed in protected type", N);
352 -- Issue a warning if the abstract subprogram is neither a dispatching
353 -- operation nor an operation that overrides an inherited subprogram or
354 -- predefined operator, since this most likely indicates a mistake.
356 elsif Warn_On_Redundant_Constructs
357 and then not Is_Dispatching_Operation (Designator)
358 and then not Is_Overriding_Operation (Designator)
359 and then (not Is_Operator_Symbol_Name (Chars (Designator))
360 or else Scop /= Scope (Etype (First_Formal (Designator))))
363 ("?abstract subprogram is not dispatching or overriding", N);
366 Generate_Reference_To_Formals (Designator);
367 end Analyze_Abstract_Subprogram_Declaration;
369 ----------------------------------------
370 -- Analyze_Extended_Return_Statement --
371 ----------------------------------------
373 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
375 Analyze_Return_Statement (N);
376 end Analyze_Extended_Return_Statement;
378 ----------------------------
379 -- Analyze_Function_Call --
380 ----------------------------
382 procedure Analyze_Function_Call (N : Node_Id) is
383 P : constant Node_Id := Name (N);
384 L : constant List_Id := Parameter_Associations (N);
390 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
391 -- as B (A, X). If the rewriting is successful, the call has been
392 -- analyzed and we just return.
394 if Nkind (P) = N_Selected_Component
395 and then Name (N) /= P
396 and then Is_Rewrite_Substitution (N)
397 and then Present (Etype (N))
402 -- If error analyzing name, then set Any_Type as result type and return
404 if Etype (P) = Any_Type then
405 Set_Etype (N, Any_Type);
409 -- Otherwise analyze the parameters
413 while Present (Actual) loop
415 Check_Parameterless_Call (Actual);
421 end Analyze_Function_Call;
423 -----------------------------
424 -- Analyze_Function_Return --
425 -----------------------------
427 procedure Analyze_Function_Return (N : Node_Id) is
428 Loc : constant Source_Ptr := Sloc (N);
429 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
430 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
432 R_Type : constant Entity_Id := Etype (Scope_Id);
433 -- Function result subtype
435 procedure Check_Limited_Return (Expr : Node_Id);
436 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
437 -- limited types. Used only for simple return statements.
438 -- Expr is the expression returned.
440 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
441 -- Check that the return_subtype_indication properly matches the result
442 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
444 --------------------------
445 -- Check_Limited_Return --
446 --------------------------
448 procedure Check_Limited_Return (Expr : Node_Id) is
450 -- Ada 2005 (AI-318-02): Return-by-reference types have been
451 -- removed and replaced by anonymous access results. This is an
452 -- incompatibility with Ada 95. Not clear whether this should be
453 -- enforced yet or perhaps controllable with special switch. ???
455 if Is_Limited_Type (R_Type)
456 and then Comes_From_Source (N)
457 and then not In_Instance_Body
458 and then not OK_For_Limited_Init_In_05 (Expr)
462 if Ada_Version >= Ada_05
463 and then not Debug_Flag_Dot_L
464 and then not GNAT_Mode
467 ("(Ada 2005) cannot copy object of a limited type " &
468 "(RM-2005 6.5(5.5/2))", Expr);
469 if Is_Inherently_Limited_Type (R_Type) then
471 ("\return by reference not permitted in Ada 2005", Expr);
474 -- Warn in Ada 95 mode, to give folks a heads up about this
477 -- In GNAT mode, this is just a warning, to allow it to be
478 -- evilly turned off. Otherwise it is a real error.
480 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
481 if Is_Inherently_Limited_Type (R_Type) then
483 ("return by reference not permitted in Ada 2005 " &
484 "(RM-2005 6.5(5.5/2))?", Expr);
487 ("cannot copy object of a limited type in Ada 2005 " &
488 "(RM-2005 6.5(5.5/2))?", Expr);
491 -- Ada 95 mode, compatibility warnings disabled
494 return; -- skip continuation messages below
498 ("\consider switching to return of access type", Expr);
499 Explain_Limited_Type (R_Type, Expr);
501 end Check_Limited_Return;
503 -------------------------------------
504 -- Check_Return_Subtype_Indication --
505 -------------------------------------
507 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
508 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
509 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
510 -- Subtype given in the extended return statement;
511 -- this must match R_Type.
513 Subtype_Ind : constant Node_Id :=
514 Object_Definition (Original_Node (Obj_Decl));
516 R_Type_Is_Anon_Access :
518 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
520 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
522 Ekind (R_Type) = E_Anonymous_Access_Type;
523 -- True if return type of the function is an anonymous access type
524 -- Can't we make Is_Anonymous_Access_Type in einfo ???
526 R_Stm_Type_Is_Anon_Access :
528 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
530 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
532 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
533 -- True if type of the return object is an anonymous access type
536 -- First, avoid cascade errors:
538 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
542 -- "return access T" case; check that the return statement also has
543 -- "access T", and that the subtypes statically match:
545 if R_Type_Is_Anon_Access then
546 if R_Stm_Type_Is_Anon_Access then
547 if Base_Type (Designated_Type (R_Stm_Type)) /=
548 Base_Type (Designated_Type (R_Type))
549 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
552 ("subtype must statically match function result subtype",
553 Subtype_Mark (Subtype_Ind));
557 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
560 -- Subtype_indication case; check that the types are the same, and
561 -- statically match if appropriate. A null exclusion may be present
562 -- on the return type, on the function specification, on the object
563 -- declaration or on the subtype itself.
565 elsif Base_Type (R_Stm_Type) = Base_Type (R_Type) then
566 if Is_Access_Type (R_Type)
568 (Can_Never_Be_Null (R_Type)
569 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
570 Can_Never_Be_Null (R_Stm_Type)
573 ("subtype must statically match function result subtype",
577 if Is_Constrained (R_Type) then
578 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
580 ("subtype must statically match function result subtype",
585 -- If the function's result type doesn't match the return object
586 -- entity's type, then we check for the case where the result type
587 -- is class-wide, and allow the declaration if the type of the object
588 -- definition matches the class-wide type. This prevents rejection
589 -- in the case where the object declaration is initialized by a call
590 -- to a build-in-place function with a specific result type and the
591 -- object entity had its type changed to that specific type. (Note
592 -- that the ARG believes that return objects should be allowed to
593 -- have a type covered by a class-wide result type in any case, so
594 -- once that relaxation is made (see AI05-32), the above check for
595 -- type compatibility should be changed to test Covers rather than
596 -- equality, and then the following special test will no longer be
599 elsif Is_Class_Wide_Type (R_Type)
601 R_Type = Etype (Object_Definition (Original_Node (Obj_Decl)))
607 ("wrong type for return_subtype_indication", Subtype_Ind);
609 end Check_Return_Subtype_Indication;
611 ---------------------
612 -- Local Variables --
613 ---------------------
617 -- Start of processing for Analyze_Function_Return
620 Set_Return_Present (Scope_Id);
622 if Nkind (N) = N_Simple_Return_Statement then
623 Expr := Expression (N);
624 Analyze_And_Resolve (Expr, R_Type);
625 Check_Limited_Return (Expr);
628 -- Analyze parts specific to extended_return_statement:
631 Obj_Decl : constant Node_Id :=
632 Last (Return_Object_Declarations (N));
634 HSS : constant Node_Id := Handled_Statement_Sequence (N);
637 Expr := Expression (Obj_Decl);
639 -- Note: The check for OK_For_Limited_Init will happen in
640 -- Analyze_Object_Declaration; we treat it as a normal
641 -- object declaration.
645 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
646 Check_Return_Subtype_Indication (Obj_Decl);
648 if Present (HSS) then
651 if Present (Exception_Handlers (HSS)) then
653 -- ???Has_Nested_Block_With_Handler needs to be set.
654 -- Probably by creating an actual N_Block_Statement.
655 -- Probably in Expand.
661 Check_References (Stm_Entity);
665 -- Case of Expr present
669 -- Defend against previous errors
671 and then Nkind (Expr) /= N_Empty
672 and then Present (Etype (Expr))
674 -- Apply constraint check. Note that this is done before the implicit
675 -- conversion of the expression done for anonymous access types to
676 -- ensure correct generation of the null-excluding check associated
677 -- with null-excluding expressions found in return statements.
679 Apply_Constraint_Check (Expr, R_Type);
681 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
682 -- type, apply an implicit conversion of the expression to that type
683 -- to force appropriate static and run-time accessibility checks.
685 if Ada_Version >= Ada_05
686 and then Ekind (R_Type) = E_Anonymous_Access_Type
688 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
689 Analyze_And_Resolve (Expr, R_Type);
692 -- If the result type is class-wide, then check that the return
693 -- expression's type is not declared at a deeper level than the
694 -- function (RM05-6.5(5.6/2)).
696 if Ada_Version >= Ada_05
697 and then Is_Class_Wide_Type (R_Type)
699 if Type_Access_Level (Etype (Expr)) >
700 Subprogram_Access_Level (Scope_Id)
703 ("level of return expression type is deeper than " &
704 "class-wide function!", Expr);
708 if (Is_Class_Wide_Type (Etype (Expr))
709 or else Is_Dynamically_Tagged (Expr))
710 and then not Is_Class_Wide_Type (R_Type)
713 ("dynamically tagged expression not allowed!", Expr);
716 -- ??? A real run-time accessibility check is needed in cases
717 -- involving dereferences of access parameters. For now we just
718 -- check the static cases.
720 if (Ada_Version < Ada_05 or else Debug_Flag_Dot_L)
721 and then Is_Inherently_Limited_Type (Etype (Scope_Id))
722 and then Object_Access_Level (Expr) >
723 Subprogram_Access_Level (Scope_Id)
726 Make_Raise_Program_Error (Loc,
727 Reason => PE_Accessibility_Check_Failed));
731 ("cannot return a local value by reference?", N);
733 ("\& will be raised at run time?",
734 N, Standard_Program_Error);
738 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
739 and then Null_Exclusion_Present (Parent (Scope_Id))
741 Apply_Compile_Time_Constraint_Error
743 Msg => "(Ada 2005) null not allowed for "
744 & "null-excluding return?",
745 Reason => CE_Null_Not_Allowed);
748 end Analyze_Function_Return;
750 -------------------------------------
751 -- Analyze_Generic_Subprogram_Body --
752 -------------------------------------
754 procedure Analyze_Generic_Subprogram_Body
758 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
759 Kind : constant Entity_Kind := Ekind (Gen_Id);
765 -- Copy body and disable expansion while analyzing the generic For a
766 -- stub, do not copy the stub (which would load the proper body), this
767 -- will be done when the proper body is analyzed.
769 if Nkind (N) /= N_Subprogram_Body_Stub then
770 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
775 Spec := Specification (N);
777 -- Within the body of the generic, the subprogram is callable, and
778 -- behaves like the corresponding non-generic unit.
780 Body_Id := Defining_Entity (Spec);
782 if Kind = E_Generic_Procedure
783 and then Nkind (Spec) /= N_Procedure_Specification
785 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
788 elsif Kind = E_Generic_Function
789 and then Nkind (Spec) /= N_Function_Specification
791 Error_Msg_N ("invalid body for generic function ", Body_Id);
795 Set_Corresponding_Body (Gen_Decl, Body_Id);
797 if Has_Completion (Gen_Id)
798 and then Nkind (Parent (N)) /= N_Subunit
800 Error_Msg_N ("duplicate generic body", N);
803 Set_Has_Completion (Gen_Id);
806 if Nkind (N) = N_Subprogram_Body_Stub then
807 Set_Ekind (Defining_Entity (Specification (N)), Kind);
809 Set_Corresponding_Spec (N, Gen_Id);
812 if Nkind (Parent (N)) = N_Compilation_Unit then
813 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
816 -- Make generic parameters immediately visible in the body. They are
817 -- needed to process the formals declarations. Then make the formals
818 -- visible in a separate step.
824 First_Ent : Entity_Id;
827 First_Ent := First_Entity (Gen_Id);
830 while Present (E) and then not Is_Formal (E) loop
835 Set_Use (Generic_Formal_Declarations (Gen_Decl));
837 -- Now generic formals are visible, and the specification can be
838 -- analyzed, for subsequent conformance check.
840 Body_Id := Analyze_Subprogram_Specification (Spec);
842 -- Make formal parameters visible
846 -- E is the first formal parameter, we loop through the formals
847 -- installing them so that they will be visible.
849 Set_First_Entity (Gen_Id, E);
850 while Present (E) loop
856 -- Visible generic entity is callable within its own body
858 Set_Ekind (Gen_Id, Ekind (Body_Id));
859 Set_Ekind (Body_Id, E_Subprogram_Body);
860 Set_Convention (Body_Id, Convention (Gen_Id));
861 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
862 Set_Scope (Body_Id, Scope (Gen_Id));
863 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
865 if Nkind (N) = N_Subprogram_Body_Stub then
867 -- No body to analyze, so restore state of generic unit
869 Set_Ekind (Gen_Id, Kind);
870 Set_Ekind (Body_Id, Kind);
872 if Present (First_Ent) then
873 Set_First_Entity (Gen_Id, First_Ent);
880 -- If this is a compilation unit, it must be made visible explicitly,
881 -- because the compilation of the declaration, unlike other library
882 -- unit declarations, does not. If it is not a unit, the following
883 -- is redundant but harmless.
885 Set_Is_Immediately_Visible (Gen_Id);
886 Reference_Body_Formals (Gen_Id, Body_Id);
888 if Is_Child_Unit (Gen_Id) then
889 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
892 Set_Actual_Subtypes (N, Current_Scope);
893 Analyze_Declarations (Declarations (N));
895 Analyze (Handled_Statement_Sequence (N));
897 Save_Global_References (Original_Node (N));
899 -- Prior to exiting the scope, include generic formals again (if any
900 -- are present) in the set of local entities.
902 if Present (First_Ent) then
903 Set_First_Entity (Gen_Id, First_Ent);
906 Check_References (Gen_Id);
909 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
911 Check_Subprogram_Order (N);
913 -- Outside of its body, unit is generic again
915 Set_Ekind (Gen_Id, Kind);
916 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
919 Style.Check_Identifier (Body_Id, Gen_Id);
922 end Analyze_Generic_Subprogram_Body;
924 -----------------------------
925 -- Analyze_Operator_Symbol --
926 -----------------------------
928 -- An operator symbol such as "+" or "and" may appear in context where the
929 -- literal denotes an entity name, such as "+"(x, y) or in context when it
930 -- is just a string, as in (conjunction = "or"). In these cases the parser
931 -- generates this node, and the semantics does the disambiguation. Other
932 -- such case are actuals in an instantiation, the generic unit in an
933 -- instantiation, and pragma arguments.
935 procedure Analyze_Operator_Symbol (N : Node_Id) is
936 Par : constant Node_Id := Parent (N);
939 if (Nkind (Par) = N_Function_Call
940 and then N = Name (Par))
941 or else Nkind (Par) = N_Function_Instantiation
942 or else (Nkind (Par) = N_Indexed_Component
943 and then N = Prefix (Par))
944 or else (Nkind (Par) = N_Pragma_Argument_Association
945 and then not Is_Pragma_String_Literal (Par))
946 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
947 or else (Nkind (Par) = N_Attribute_Reference
948 and then Attribute_Name (Par) /= Name_Value)
950 Find_Direct_Name (N);
953 Change_Operator_Symbol_To_String_Literal (N);
956 end Analyze_Operator_Symbol;
958 -----------------------------------
959 -- Analyze_Parameter_Association --
960 -----------------------------------
962 procedure Analyze_Parameter_Association (N : Node_Id) is
964 Analyze (Explicit_Actual_Parameter (N));
965 end Analyze_Parameter_Association;
967 ----------------------------
968 -- Analyze_Procedure_Call --
969 ----------------------------
971 procedure Analyze_Procedure_Call (N : Node_Id) is
972 Loc : constant Source_Ptr := Sloc (N);
973 P : constant Node_Id := Name (N);
974 Actuals : constant List_Id := Parameter_Associations (N);
978 procedure Analyze_Call_And_Resolve;
979 -- Do Analyze and Resolve calls for procedure call
981 ------------------------------
982 -- Analyze_Call_And_Resolve --
983 ------------------------------
985 procedure Analyze_Call_And_Resolve is
987 if Nkind (N) = N_Procedure_Call_Statement then
989 Resolve (N, Standard_Void_Type);
993 end Analyze_Call_And_Resolve;
995 -- Start of processing for Analyze_Procedure_Call
998 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
999 -- a procedure call or an entry call. The prefix may denote an access
1000 -- to subprogram type, in which case an implicit dereference applies.
1001 -- If the prefix is an indexed component (without implicit dereference)
1002 -- then the construct denotes a call to a member of an entire family.
1003 -- If the prefix is a simple name, it may still denote a call to a
1004 -- parameterless member of an entry family. Resolution of these various
1005 -- interpretations is delicate.
1009 -- If this is a call of the form Obj.Op, the call may have been
1010 -- analyzed and possibly rewritten into a block, in which case
1013 if Analyzed (N) then
1017 -- If error analyzing prefix, then set Any_Type as result and return
1019 if Etype (P) = Any_Type then
1020 Set_Etype (N, Any_Type);
1024 -- Otherwise analyze the parameters
1026 if Present (Actuals) then
1027 Actual := First (Actuals);
1029 while Present (Actual) loop
1031 Check_Parameterless_Call (Actual);
1036 -- Special processing for Elab_Spec and Elab_Body calls
1038 if Nkind (P) = N_Attribute_Reference
1039 and then (Attribute_Name (P) = Name_Elab_Spec
1040 or else Attribute_Name (P) = Name_Elab_Body)
1042 if Present (Actuals) then
1044 ("no parameters allowed for this call", First (Actuals));
1048 Set_Etype (N, Standard_Void_Type);
1051 elsif Is_Entity_Name (P)
1052 and then Is_Record_Type (Etype (Entity (P)))
1053 and then Remote_AST_I_Dereference (P)
1057 elsif Is_Entity_Name (P)
1058 and then Ekind (Entity (P)) /= E_Entry_Family
1060 if Is_Access_Type (Etype (P))
1061 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1062 and then No (Actuals)
1063 and then Comes_From_Source (N)
1065 Error_Msg_N ("missing explicit dereference in call", N);
1068 Analyze_Call_And_Resolve;
1070 -- If the prefix is the simple name of an entry family, this is
1071 -- a parameterless call from within the task body itself.
1073 elsif Is_Entity_Name (P)
1074 and then Nkind (P) = N_Identifier
1075 and then Ekind (Entity (P)) = E_Entry_Family
1076 and then Present (Actuals)
1077 and then No (Next (First (Actuals)))
1079 -- Can be call to parameterless entry family. What appears to be the
1080 -- sole argument is in fact the entry index. Rewrite prefix of node
1081 -- accordingly. Source representation is unchanged by this
1085 Make_Indexed_Component (Loc,
1087 Make_Selected_Component (Loc,
1088 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1089 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1090 Expressions => Actuals);
1091 Set_Name (N, New_N);
1092 Set_Etype (New_N, Standard_Void_Type);
1093 Set_Parameter_Associations (N, No_List);
1094 Analyze_Call_And_Resolve;
1096 elsif Nkind (P) = N_Explicit_Dereference then
1097 if Ekind (Etype (P)) = E_Subprogram_Type then
1098 Analyze_Call_And_Resolve;
1100 Error_Msg_N ("expect access to procedure in call", P);
1103 -- The name can be a selected component or an indexed component that
1104 -- yields an access to subprogram. Such a prefix is legal if the call
1105 -- has parameter associations.
1107 elsif Is_Access_Type (Etype (P))
1108 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1110 if Present (Actuals) then
1111 Analyze_Call_And_Resolve;
1113 Error_Msg_N ("missing explicit dereference in call ", N);
1116 -- If not an access to subprogram, then the prefix must resolve to the
1117 -- name of an entry, entry family, or protected operation.
1119 -- For the case of a simple entry call, P is a selected component where
1120 -- the prefix is the task and the selector name is the entry. A call to
1121 -- a protected procedure will have the same syntax. If the protected
1122 -- object contains overloaded operations, the entity may appear as a
1123 -- function, the context will select the operation whose type is Void.
1125 elsif Nkind (P) = N_Selected_Component
1126 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1128 Ekind (Entity (Selector_Name (P))) = E_Procedure
1130 Ekind (Entity (Selector_Name (P))) = E_Function)
1132 Analyze_Call_And_Resolve;
1134 elsif Nkind (P) = N_Selected_Component
1135 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1136 and then Present (Actuals)
1137 and then No (Next (First (Actuals)))
1139 -- Can be call to parameterless entry family. What appears to be the
1140 -- sole argument is in fact the entry index. Rewrite prefix of node
1141 -- accordingly. Source representation is unchanged by this
1145 Make_Indexed_Component (Loc,
1146 Prefix => New_Copy (P),
1147 Expressions => Actuals);
1148 Set_Name (N, New_N);
1149 Set_Etype (New_N, Standard_Void_Type);
1150 Set_Parameter_Associations (N, No_List);
1151 Analyze_Call_And_Resolve;
1153 -- For the case of a reference to an element of an entry family, P is
1154 -- an indexed component whose prefix is a selected component (task and
1155 -- entry family), and whose index is the entry family index.
1157 elsif Nkind (P) = N_Indexed_Component
1158 and then Nkind (Prefix (P)) = N_Selected_Component
1159 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1161 Analyze_Call_And_Resolve;
1163 -- If the prefix is the name of an entry family, it is a call from
1164 -- within the task body itself.
1166 elsif Nkind (P) = N_Indexed_Component
1167 and then Nkind (Prefix (P)) = N_Identifier
1168 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1171 Make_Selected_Component (Loc,
1172 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1173 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1174 Rewrite (Prefix (P), New_N);
1176 Analyze_Call_And_Resolve;
1178 -- Anything else is an error
1181 Error_Msg_N ("invalid procedure or entry call", N);
1183 end Analyze_Procedure_Call;
1185 -------------------------------------
1186 -- Analyze_Simple_Return_Statement --
1187 -------------------------------------
1189 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1191 if Present (Expression (N)) then
1192 Mark_Coextensions (N, Expression (N));
1195 Analyze_Return_Statement (N);
1196 end Analyze_Simple_Return_Statement;
1198 -------------------------
1199 -- Analyze_Return_Type --
1200 -------------------------
1202 procedure Analyze_Return_Type (N : Node_Id) is
1203 Designator : constant Entity_Id := Defining_Entity (N);
1204 Typ : Entity_Id := Empty;
1207 -- Normal case where result definition does not indicate an error
1209 if Result_Definition (N) /= Error then
1210 if Nkind (Result_Definition (N)) = N_Access_Definition then
1211 Typ := Access_Definition (N, Result_Definition (N));
1212 Set_Parent (Typ, Result_Definition (N));
1213 Set_Is_Local_Anonymous_Access (Typ);
1214 Set_Etype (Designator, Typ);
1216 -- Subtype_Mark case
1219 Find_Type (Result_Definition (N));
1220 Typ := Entity (Result_Definition (N));
1221 Set_Etype (Designator, Typ);
1223 if Ekind (Typ) = E_Incomplete_Type
1224 and then Is_Value_Type (Typ)
1228 elsif Ekind (Typ) = E_Incomplete_Type
1229 or else (Is_Class_Wide_Type (Typ)
1231 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1234 ("invalid use of incomplete type", Result_Definition (N));
1238 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1240 Null_Exclusion_Static_Checks (N);
1242 -- Case where result definition does indicate an error
1245 Set_Etype (Designator, Any_Type);
1247 end Analyze_Return_Type;
1249 -----------------------------
1250 -- Analyze_Subprogram_Body --
1251 -----------------------------
1253 -- This procedure is called for regular subprogram bodies, generic bodies,
1254 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1255 -- specification matters, and is used to create a proper declaration for
1256 -- the subprogram, or to perform conformance checks.
1258 procedure Analyze_Subprogram_Body (N : Node_Id) is
1259 Loc : constant Source_Ptr := Sloc (N);
1260 Body_Deleted : constant Boolean := False;
1261 Body_Spec : constant Node_Id := Specification (N);
1262 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1263 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1264 Conformant : Boolean;
1266 Missing_Ret : Boolean;
1268 Prot_Typ : Entity_Id := Empty;
1269 Spec_Id : Entity_Id;
1270 Spec_Decl : Node_Id := Empty;
1272 Last_Real_Spec_Entity : Entity_Id := Empty;
1273 -- When we analyze a separate spec, the entity chain ends up containing
1274 -- the formals, as well as any itypes generated during analysis of the
1275 -- default expressions for parameters, or the arguments of associated
1276 -- precondition/postcondition pragmas (which are analyzed in the context
1277 -- of the spec since they have visibility on formals).
1279 -- These entities belong with the spec and not the body. However we do
1280 -- the analysis of the body in the context of the spec (again to obtain
1281 -- visibility to the formals), and all the entities generated during
1282 -- this analysis end up also chained to the entity chain of the spec.
1283 -- But they really belong to the body, and there is circuitry to move
1284 -- them from the spec to the body.
1286 -- However, when we do this move, we don't want to move the real spec
1287 -- entities (first para above) to the body. The Last_Real_Spec_Entity
1288 -- variable points to the last real spec entity, so we only move those
1289 -- chained beyond that point. It is initialized to Empty to deal with
1290 -- the case where there is no separate spec.
1292 procedure Check_Anonymous_Return;
1293 -- (Ada 2005): if a function returns an access type that denotes a task,
1294 -- or a type that contains tasks, we must create a master entity for
1295 -- the anonymous type, which typically will be used in an allocator
1296 -- in the body of the function.
1298 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1299 -- Look ahead to recognize a pragma that may appear after the body.
1300 -- If there is a previous spec, check that it appears in the same
1301 -- declarative part. If the pragma is Inline_Always, perform inlining
1302 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1303 -- If the body acts as a spec, and inlining is required, we create a
1304 -- subprogram declaration for it, in order to attach the body to inline.
1305 -- If pragma does not appear after the body, check whether there is
1306 -- an inline pragma before any local declarations.
1308 procedure Set_Trivial_Subprogram (N : Node_Id);
1309 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
1310 -- subprogram whose body is being analyzed. N is the statement node
1311 -- causing the flag to be set, if the following statement is a return
1312 -- of an entity, we mark the entity as set in source to suppress any
1313 -- warning on the stylized use of function stubs with a dummy return.
1315 procedure Verify_Overriding_Indicator;
1316 -- If there was a previous spec, the entity has been entered in the
1317 -- current scope previously. If the body itself carries an overriding
1318 -- indicator, check that it is consistent with the known status of the
1321 ----------------------------
1322 -- Check_Anonymous_Return --
1323 ----------------------------
1325 procedure Check_Anonymous_Return is
1330 if Present (Spec_Id) then
1336 if Ekind (Scop) = E_Function
1337 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1338 and then Has_Task (Designated_Type (Etype (Scop)))
1339 and then Expander_Active
1342 Make_Object_Declaration (Loc,
1343 Defining_Identifier =>
1344 Make_Defining_Identifier (Loc, Name_uMaster),
1345 Constant_Present => True,
1346 Object_Definition =>
1347 New_Reference_To (RTE (RE_Master_Id), Loc),
1349 Make_Explicit_Dereference (Loc,
1350 New_Reference_To (RTE (RE_Current_Master), Loc)));
1352 if Present (Declarations (N)) then
1353 Prepend (Decl, Declarations (N));
1355 Set_Declarations (N, New_List (Decl));
1358 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1359 Set_Has_Master_Entity (Scop);
1361 end Check_Anonymous_Return;
1363 -------------------------
1364 -- Check_Inline_Pragma --
1365 -------------------------
1367 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1371 function Is_Inline_Pragma (N : Node_Id) return Boolean;
1372 -- True when N is a pragma Inline or Inline_Awlays that applies
1373 -- to this subprogram.
1375 -----------------------
1376 -- Is_Inline_Pragma --
1377 -----------------------
1379 function Is_Inline_Pragma (N : Node_Id) return Boolean is
1382 Nkind (N) = N_Pragma
1384 (Pragma_Name (N) = Name_Inline_Always
1387 and then Pragma_Name (N) = Name_Inline))
1390 (Expression (First (Pragma_Argument_Associations (N))))
1392 end Is_Inline_Pragma;
1394 -- Start of processing for Check_Inline_Pragma
1397 if not Expander_Active then
1401 if Is_List_Member (N)
1402 and then Present (Next (N))
1403 and then Is_Inline_Pragma (Next (N))
1407 elsif Nkind (N) /= N_Subprogram_Body_Stub
1408 and then Present (Declarations (N))
1409 and then Is_Inline_Pragma (First (Declarations (N)))
1411 Prag := First (Declarations (N));
1417 if Present (Prag) then
1418 if Present (Spec_Id) then
1419 if List_Containing (N) =
1420 List_Containing (Unit_Declaration_Node (Spec_Id))
1426 -- Create a subprogram declaration, to make treatment uniform
1429 Subp : constant Entity_Id :=
1430 Make_Defining_Identifier (Loc, Chars (Body_Id));
1431 Decl : constant Node_Id :=
1432 Make_Subprogram_Declaration (Loc,
1433 Specification => New_Copy_Tree (Specification (N)));
1435 Set_Defining_Unit_Name (Specification (Decl), Subp);
1437 if Present (First_Formal (Body_Id)) then
1438 Plist := Copy_Parameter_List (Body_Id);
1439 Set_Parameter_Specifications
1440 (Specification (Decl), Plist);
1443 Insert_Before (N, Decl);
1446 Set_Has_Pragma_Inline (Subp);
1448 if Pragma_Name (Prag) = Name_Inline_Always then
1449 Set_Is_Inlined (Subp);
1450 Set_Has_Pragma_Inline_Always (Subp);
1457 end Check_Inline_Pragma;
1459 ----------------------------
1460 -- Set_Trivial_Subprogram --
1461 ----------------------------
1463 procedure Set_Trivial_Subprogram (N : Node_Id) is
1464 Nxt : constant Node_Id := Next (N);
1467 Set_Is_Trivial_Subprogram (Body_Id);
1469 if Present (Spec_Id) then
1470 Set_Is_Trivial_Subprogram (Spec_Id);
1474 and then Nkind (Nxt) = N_Simple_Return_Statement
1475 and then No (Next (Nxt))
1476 and then Present (Expression (Nxt))
1477 and then Is_Entity_Name (Expression (Nxt))
1479 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
1481 end Set_Trivial_Subprogram;
1483 ---------------------------------
1484 -- Verify_Overriding_Indicator --
1485 ---------------------------------
1487 procedure Verify_Overriding_Indicator is
1489 if Must_Override (Body_Spec) then
1490 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
1491 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
1495 elsif not Is_Overriding_Operation (Spec_Id) then
1497 ("subprogram& is not overriding", Body_Spec, Spec_Id);
1500 elsif Must_Not_Override (Body_Spec) then
1501 if Is_Overriding_Operation (Spec_Id) then
1503 ("subprogram& overrides inherited operation",
1504 Body_Spec, Spec_Id);
1506 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
1507 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
1510 ("subprogram & overrides predefined operator ",
1511 Body_Spec, Spec_Id);
1513 -- If this is not a primitive operation the overriding indicator
1514 -- is altogether illegal.
1516 elsif not Is_Primitive (Spec_Id) then
1517 Error_Msg_N ("overriding indicator only allowed " &
1518 "if subprogram is primitive",
1522 end Verify_Overriding_Indicator;
1524 -- Start of processing for Analyze_Subprogram_Body
1527 if Debug_Flag_C then
1528 Write_Str ("==== Compiling subprogram body ");
1529 Write_Name (Chars (Body_Id));
1530 Write_Str (" from ");
1531 Write_Location (Loc);
1535 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1537 -- Generic subprograms are handled separately. They always have a
1538 -- generic specification. Determine whether current scope has a
1539 -- previous declaration.
1541 -- If the subprogram body is defined within an instance of the same
1542 -- name, the instance appears as a package renaming, and will be hidden
1543 -- within the subprogram.
1545 if Present (Prev_Id)
1546 and then not Is_Overloadable (Prev_Id)
1547 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
1548 or else Comes_From_Source (Prev_Id))
1550 if Is_Generic_Subprogram (Prev_Id) then
1552 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1553 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1555 Analyze_Generic_Subprogram_Body (N, Spec_Id);
1559 -- Previous entity conflicts with subprogram name. Attempting to
1560 -- enter name will post error.
1562 Enter_Name (Body_Id);
1566 -- Non-generic case, find the subprogram declaration, if one was seen,
1567 -- or enter new overloaded entity in the current scope. If the
1568 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
1569 -- part of the context of one of its subunits. No need to redo the
1572 elsif Prev_Id = Body_Id
1573 and then Has_Completion (Body_Id)
1578 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
1580 if Nkind (N) = N_Subprogram_Body_Stub
1581 or else No (Corresponding_Spec (N))
1583 Spec_Id := Find_Corresponding_Spec (N);
1585 -- If this is a duplicate body, no point in analyzing it
1587 if Error_Posted (N) then
1591 -- A subprogram body should cause freezing of its own declaration,
1592 -- but if there was no previous explicit declaration, then the
1593 -- subprogram will get frozen too late (there may be code within
1594 -- the body that depends on the subprogram having been frozen,
1595 -- such as uses of extra formals), so we force it to be frozen
1596 -- here. Same holds if the body and spec are compilation units.
1598 if No (Spec_Id) then
1599 Freeze_Before (N, Body_Id);
1601 elsif Nkind (Parent (N)) = N_Compilation_Unit then
1602 Freeze_Before (N, Spec_Id);
1605 Spec_Id := Corresponding_Spec (N);
1609 -- Do not inline any subprogram that contains nested subprograms, since
1610 -- the backend inlining circuit seems to generate uninitialized
1611 -- references in this case. We know this happens in the case of front
1612 -- end ZCX support, but it also appears it can happen in other cases as
1613 -- well. The backend often rejects attempts to inline in the case of
1614 -- nested procedures anyway, so little if anything is lost by this.
1615 -- Note that this is test is for the benefit of the back-end. There is
1616 -- a separate test for front-end inlining that also rejects nested
1619 -- Do not do this test if errors have been detected, because in some
1620 -- error cases, this code blows up, and we don't need it anyway if
1621 -- there have been errors, since we won't get to the linker anyway.
1623 if Comes_From_Source (Body_Id)
1624 and then Serious_Errors_Detected = 0
1628 P_Ent := Scope (P_Ent);
1629 exit when No (P_Ent) or else P_Ent = Standard_Standard;
1631 if Is_Subprogram (P_Ent) then
1632 Set_Is_Inlined (P_Ent, False);
1634 if Comes_From_Source (P_Ent)
1635 and then Has_Pragma_Inline (P_Ent)
1638 ("cannot inline& (nested subprogram)?",
1645 Check_Inline_Pragma (Spec_Id);
1647 -- Case of fully private operation in the body of the protected type.
1648 -- We must create a declaration for the subprogram, in order to attach
1649 -- the protected subprogram that will be used in internal calls.
1652 and then Comes_From_Source (N)
1653 and then Is_Protected_Type (Current_Scope)
1662 Formal := First_Formal (Body_Id);
1664 -- The protected operation always has at least one formal, namely
1665 -- the object itself, but it is only placed in the parameter list
1666 -- if expansion is enabled.
1669 or else Expander_Active
1671 Plist := Copy_Parameter_List (Body_Id);
1676 if Nkind (Body_Spec) = N_Procedure_Specification then
1678 Make_Procedure_Specification (Loc,
1679 Defining_Unit_Name =>
1680 Make_Defining_Identifier (Sloc (Body_Id),
1681 Chars => Chars (Body_Id)),
1682 Parameter_Specifications => Plist);
1685 Make_Function_Specification (Loc,
1686 Defining_Unit_Name =>
1687 Make_Defining_Identifier (Sloc (Body_Id),
1688 Chars => Chars (Body_Id)),
1689 Parameter_Specifications => Plist,
1690 Result_Definition =>
1691 New_Occurrence_Of (Etype (Body_Id), Loc));
1695 Make_Subprogram_Declaration (Loc,
1696 Specification => New_Spec);
1697 Insert_Before (N, Decl);
1698 Spec_Id := Defining_Unit_Name (New_Spec);
1700 -- Indicate that the entity comes from source, to ensure that
1701 -- cross-reference information is properly generated. The body
1702 -- itself is rewritten during expansion, and the body entity will
1703 -- not appear in calls to the operation.
1705 Set_Comes_From_Source (Spec_Id, True);
1707 Set_Has_Completion (Spec_Id);
1708 Set_Convention (Spec_Id, Convention_Protected);
1711 elsif Present (Spec_Id) then
1712 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1713 Verify_Overriding_Indicator;
1715 -- In general, the spec will be frozen when we start analyzing the
1716 -- body. However, for internally generated operations, such as
1717 -- wrapper functions for inherited operations with controlling
1718 -- results, the spec may not have been frozen by the time we
1719 -- expand the freeze actions that include the bodies. In particular,
1720 -- extra formals for accessibility or for return-in-place may need
1721 -- to be generated. Freeze nodes, if any, are inserted before the
1724 if not Is_Frozen (Spec_Id)
1725 and then Expander_Active
1727 -- Force the generation of its freezing node to ensure proper
1728 -- management of access types in the backend.
1730 -- This is definitely needed for some cases, but it is not clear
1731 -- why, to be investigated further???
1733 Set_Has_Delayed_Freeze (Spec_Id);
1734 Insert_Actions (N, Freeze_Entity (Spec_Id, Loc));
1738 -- Place subprogram on scope stack, and make formals visible. If there
1739 -- is a spec, the visible entity remains that of the spec.
1741 if Present (Spec_Id) then
1742 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1744 if Is_Child_Unit (Spec_Id) then
1745 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
1749 Style.Check_Identifier (Body_Id, Spec_Id);
1752 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1753 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1755 if Is_Abstract_Subprogram (Spec_Id) then
1756 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1760 Set_Convention (Body_Id, Convention (Spec_Id));
1761 Set_Has_Completion (Spec_Id);
1763 if Is_Protected_Type (Scope (Spec_Id)) then
1764 Prot_Typ := Scope (Spec_Id);
1767 -- If this is a body generated for a renaming, do not check for
1768 -- full conformance. The check is redundant, because the spec of
1769 -- the body is a copy of the spec in the renaming declaration,
1770 -- and the test can lead to spurious errors on nested defaults.
1772 if Present (Spec_Decl)
1773 and then not Comes_From_Source (N)
1775 (Nkind (Original_Node (Spec_Decl)) =
1776 N_Subprogram_Renaming_Declaration
1777 or else (Present (Corresponding_Body (Spec_Decl))
1779 Nkind (Unit_Declaration_Node
1780 (Corresponding_Body (Spec_Decl))) =
1781 N_Subprogram_Renaming_Declaration))
1788 Fully_Conformant, True, Conformant, Body_Id);
1791 -- If the body is not fully conformant, we have to decide if we
1792 -- should analyze it or not. If it has a really messed up profile
1793 -- then we probably should not analyze it, since we will get too
1794 -- many bogus messages.
1796 -- Our decision is to go ahead in the non-fully conformant case
1797 -- only if it is at least mode conformant with the spec. Note
1798 -- that the call to Check_Fully_Conformant has issued the proper
1799 -- error messages to complain about the lack of conformance.
1802 and then not Mode_Conformant (Body_Id, Spec_Id)
1808 if Spec_Id /= Body_Id then
1809 Reference_Body_Formals (Spec_Id, Body_Id);
1812 if Nkind (N) /= N_Subprogram_Body_Stub then
1813 Set_Corresponding_Spec (N, Spec_Id);
1815 -- Ada 2005 (AI-345): If the operation is a primitive operation
1816 -- of a concurrent type, the type of the first parameter has been
1817 -- replaced with the corresponding record, which is the proper
1818 -- run-time structure to use. However, within the body there may
1819 -- be uses of the formals that depend on primitive operations
1820 -- of the type (in particular calls in prefixed form) for which
1821 -- we need the original concurrent type. The operation may have
1822 -- several controlling formals, so the replacement must be done
1825 if Comes_From_Source (Spec_Id)
1826 and then Present (First_Entity (Spec_Id))
1827 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
1828 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
1830 Present (Abstract_Interfaces (Etype (First_Entity (Spec_Id))))
1833 (Corresponding_Concurrent_Type
1834 (Etype (First_Entity (Spec_Id))))
1837 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
1841 Form := First_Formal (Spec_Id);
1842 while Present (Form) loop
1843 if Etype (Form) = Typ then
1844 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
1852 -- Make the formals visible, and place subprogram on scope stack.
1853 -- This is also the point at which we set Last_Real_Spec_Entity
1854 -- to mark the entities which will not be moved to the body.
1856 Install_Formals (Spec_Id);
1857 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
1858 Push_Scope (Spec_Id);
1860 -- Make sure that the subprogram is immediately visible. For
1861 -- child units that have no separate spec this is indispensable.
1862 -- Otherwise it is safe albeit redundant.
1864 Set_Is_Immediately_Visible (Spec_Id);
1867 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
1868 Set_Ekind (Body_Id, E_Subprogram_Body);
1869 Set_Scope (Body_Id, Scope (Spec_Id));
1870 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
1872 -- Case of subprogram body with no previous spec
1876 and then Comes_From_Source (Body_Id)
1877 and then not Suppress_Style_Checks (Body_Id)
1878 and then not In_Instance
1880 Style.Body_With_No_Spec (N);
1883 New_Overloaded_Entity (Body_Id);
1885 if Nkind (N) /= N_Subprogram_Body_Stub then
1886 Set_Acts_As_Spec (N);
1887 Generate_Definition (Body_Id);
1889 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
1890 Generate_Reference_To_Formals (Body_Id);
1891 Install_Formals (Body_Id);
1892 Push_Scope (Body_Id);
1896 -- If the return type is an anonymous access type whose designated type
1897 -- is the limited view of a class-wide type and the non-limited view is
1898 -- available, update the return type accordingly.
1900 if Ada_Version >= Ada_05
1901 and then Comes_From_Source (N)
1908 Rtyp := Etype (Current_Scope);
1910 if Ekind (Rtyp) = E_Anonymous_Access_Type then
1911 Etyp := Directly_Designated_Type (Rtyp);
1913 if Is_Class_Wide_Type (Etyp)
1914 and then From_With_Type (Etyp)
1916 Set_Directly_Designated_Type
1917 (Etype (Current_Scope), Available_View (Etyp));
1923 -- If this is the proper body of a stub, we must verify that the stub
1924 -- conforms to the body, and to the previous spec if one was present.
1925 -- we know already that the body conforms to that spec. This test is
1926 -- only required for subprograms that come from source.
1928 if Nkind (Parent (N)) = N_Subunit
1929 and then Comes_From_Source (N)
1930 and then not Error_Posted (Body_Id)
1931 and then Nkind (Corresponding_Stub (Parent (N))) =
1932 N_Subprogram_Body_Stub
1935 Old_Id : constant Entity_Id :=
1937 (Specification (Corresponding_Stub (Parent (N))));
1939 Conformant : Boolean := False;
1942 if No (Spec_Id) then
1943 Check_Fully_Conformant (Body_Id, Old_Id);
1947 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
1949 if not Conformant then
1951 -- The stub was taken to be a new declaration. Indicate
1952 -- that it lacks a body.
1954 Set_Has_Completion (Old_Id, False);
1960 Set_Has_Completion (Body_Id);
1961 Check_Eliminated (Body_Id);
1963 if Nkind (N) = N_Subprogram_Body_Stub then
1966 elsif Present (Spec_Id)
1967 and then Expander_Active
1969 (Has_Pragma_Inline_Always (Spec_Id)
1970 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
1972 Build_Body_To_Inline (N, Spec_Id);
1975 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
1976 -- if its specification we have to install the private withed units.
1977 -- This holds for child units as well.
1979 if Is_Compilation_Unit (Body_Id)
1980 or else Nkind (Parent (N)) = N_Compilation_Unit
1982 Install_Private_With_Clauses (Body_Id);
1985 Check_Anonymous_Return;
1987 -- Set the Protected_Formal field of each extra formal of the protected
1988 -- subprogram to reference the corresponding extra formal of the
1989 -- subprogram that implements it. For regular formals this occurs when
1990 -- the protected subprogram's declaration is expanded, but the extra
1991 -- formals don't get created until the subprogram is frozen. We need to
1992 -- do this before analyzing the protected subprogram's body so that any
1993 -- references to the original subprogram's extra formals will be changed
1994 -- refer to the implementing subprogram's formals (see Expand_Formal).
1996 if Present (Spec_Id)
1997 and then Is_Protected_Type (Scope (Spec_Id))
1998 and then Present (Protected_Body_Subprogram (Spec_Id))
2001 Impl_Subp : constant Entity_Id :=
2002 Protected_Body_Subprogram (Spec_Id);
2003 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2004 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2006 while Present (Prot_Ext_Formal) loop
2007 pragma Assert (Present (Impl_Ext_Formal));
2008 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2009 Next_Formal_With_Extras (Prot_Ext_Formal);
2010 Next_Formal_With_Extras (Impl_Ext_Formal);
2015 -- Now we can go on to analyze the body
2017 HSS := Handled_Statement_Sequence (N);
2018 Set_Actual_Subtypes (N, Current_Scope);
2020 -- Deal with preconditions and postconditions
2022 Process_PPCs (N, Spec_Id, Body_Id);
2024 -- Add a declaration for the Protection object, renaming declarations
2025 -- for discriminals and privals and finally a declaration for the entry
2026 -- family index (if applicable). This form of early expansion is done
2027 -- when the Expander is active because Install_Private_Data_Declarations
2028 -- references entities which were created during regular expansion.
2031 and then Comes_From_Source (N)
2032 and then Present (Prot_Typ)
2033 and then Present (Spec_Id)
2034 and then not Is_Eliminated (Spec_Id)
2036 Install_Private_Data_Declarations
2037 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2040 -- Analyze the declarations (this call will analyze the precondition
2041 -- Check pragmas we prepended to the list, as well as the declaration
2042 -- of the _Postconditions procedure).
2044 Analyze_Declarations (Declarations (N));
2046 -- Check completion, and analyze the statements
2049 Inspect_Deferred_Constant_Completion (Declarations (N));
2052 -- Deal with end of scope processing for the body
2054 Process_End_Label (HSS, 't', Current_Scope);
2056 Check_Subprogram_Order (N);
2057 Set_Analyzed (Body_Id);
2059 -- If we have a separate spec, then the analysis of the declarations
2060 -- caused the entities in the body to be chained to the spec id, but
2061 -- we want them chained to the body id. Only the formal parameters
2062 -- end up chained to the spec id in this case.
2064 if Present (Spec_Id) then
2066 -- We must conform to the categorization of our spec
2068 Validate_Categorization_Dependency (N, Spec_Id);
2070 -- And if this is a child unit, the parent units must conform
2072 if Is_Child_Unit (Spec_Id) then
2073 Validate_Categorization_Dependency
2074 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2077 -- Here is where we move entities from the spec to the body
2079 -- Case where there are entities that stay with the spec
2081 if Present (Last_Real_Spec_Entity) then
2083 -- No body entities (happens when the only real spec entities
2084 -- come from precondition and postcondition pragmas)
2086 if No (Last_Entity (Body_Id)) then
2088 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2090 -- Body entities present (formals), so chain stuff past them
2094 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2097 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2098 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2099 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2101 -- Case where there are no spec entities, in this case there can
2102 -- be no body entities either, so just move everything.
2105 pragma Assert (No (Last_Entity (Body_Id)));
2106 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2107 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2108 Set_First_Entity (Spec_Id, Empty);
2109 Set_Last_Entity (Spec_Id, Empty);
2113 -- If function, check return statements
2115 if Nkind (Body_Spec) = N_Function_Specification then
2120 if Present (Spec_Id) then
2126 if Return_Present (Id) then
2127 Check_Returns (HSS, 'F', Missing_Ret);
2130 Set_Has_Missing_Return (Id);
2133 elsif not Is_Machine_Code_Subprogram (Id)
2134 and then not Body_Deleted
2136 Error_Msg_N ("missing RETURN statement in function body", N);
2140 -- If procedure with No_Return, check returns
2142 elsif Nkind (Body_Spec) = N_Procedure_Specification
2143 and then Present (Spec_Id)
2144 and then No_Return (Spec_Id)
2146 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2149 -- Now we are going to check for variables that are never modified in
2150 -- the body of the procedure. But first we deal with a special case
2151 -- where we want to modify this check. If the body of the subprogram
2152 -- starts with a raise statement or its equivalent, or if the body
2153 -- consists entirely of a null statement, then it is pretty obvious
2154 -- that it is OK to not reference the parameters. For example, this
2155 -- might be the following common idiom for a stubbed function:
2156 -- statement of the procedure raises an exception. In particular this
2157 -- deals with the common idiom of a stubbed function, which might
2158 -- appear as something like
2160 -- function F (A : Integer) return Some_Type;
2163 -- raise Program_Error;
2167 -- Here the purpose of X is simply to satisfy the annoying requirement
2168 -- in Ada that there be at least one return, and we certainly do not
2169 -- want to go posting warnings on X that it is not initialized! On
2170 -- the other hand, if X is entirely unreferenced that should still
2173 -- What we do is to detect these cases, and if we find them, flag the
2174 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2175 -- suppress unwanted warnings. For the case of the function stub above
2176 -- we have a special test to set X as apparently assigned to suppress
2183 -- Skip initial labels (for one thing this occurs when we are in
2184 -- front end ZCX mode, but in any case it is irrelevant), and also
2185 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2187 Stm := First (Statements (HSS));
2188 while Nkind (Stm) = N_Label
2189 or else Nkind (Stm) in N_Push_xxx_Label
2194 -- Do the test on the original statement before expansion
2197 Ostm : constant Node_Id := Original_Node (Stm);
2200 -- If explicit raise statement, turn on flag
2202 if Nkind (Ostm) = N_Raise_Statement then
2203 Set_Trivial_Subprogram (Stm);
2205 -- If null statement, and no following statements, turn on flag
2207 elsif Nkind (Stm) = N_Null_Statement
2208 and then Comes_From_Source (Stm)
2209 and then No (Next (Stm))
2211 Set_Trivial_Subprogram (Stm);
2213 -- Check for explicit call cases which likely raise an exception
2215 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2216 if Is_Entity_Name (Name (Ostm)) then
2218 Ent : constant Entity_Id := Entity (Name (Ostm));
2221 -- If the procedure is marked No_Return, then likely it
2222 -- raises an exception, but in any case it is not coming
2223 -- back here, so turn on the flag.
2225 if Ekind (Ent) = E_Procedure
2226 and then No_Return (Ent)
2228 Set_Trivial_Subprogram (Stm);
2230 -- If the procedure name is Raise_Exception, then also
2231 -- assume that it raises an exception. The main target
2232 -- here is Ada.Exceptions.Raise_Exception, but this name
2233 -- is pretty evocative in any context! Note that the
2234 -- procedure in Ada.Exceptions is not marked No_Return
2235 -- because of the annoying case of the null exception Id
2236 -- when operating in Ada 95 mode.
2238 elsif Chars (Ent) = Name_Raise_Exception then
2239 Set_Trivial_Subprogram (Stm);
2247 -- Check for variables that are never modified
2253 -- If there is a separate spec, then transfer Never_Set_In_Source
2254 -- flags from out parameters to the corresponding entities in the
2255 -- body. The reason we do that is we want to post error flags on
2256 -- the body entities, not the spec entities.
2258 if Present (Spec_Id) then
2259 E1 := First_Entity (Spec_Id);
2260 while Present (E1) loop
2261 if Ekind (E1) = E_Out_Parameter then
2262 E2 := First_Entity (Body_Id);
2263 while Present (E2) loop
2264 exit when Chars (E1) = Chars (E2);
2268 if Present (E2) then
2269 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2277 -- Check references in body unless it was deleted. Note that the
2278 -- check of Body_Deleted here is not just for efficiency, it is
2279 -- necessary to avoid junk warnings on formal parameters.
2281 if not Body_Deleted then
2282 Check_References (Body_Id);
2285 end Analyze_Subprogram_Body;
2287 ------------------------------------
2288 -- Analyze_Subprogram_Declaration --
2289 ------------------------------------
2291 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2292 Designator : constant Entity_Id :=
2293 Analyze_Subprogram_Specification (Specification (N));
2294 Scop : constant Entity_Id := Current_Scope;
2296 -- Start of processing for Analyze_Subprogram_Declaration
2299 Generate_Definition (Designator);
2301 -- Check for RCI unit subprogram declarations for illegal inlined
2302 -- subprograms and subprograms having access parameter or limited
2303 -- parameter without Read and Write attributes (RM E.2.3(12-13)).
2305 Validate_RCI_Subprogram_Declaration (N);
2309 Defining_Entity (N),
2310 " Analyze subprogram spec: ");
2312 if Debug_Flag_C then
2313 Write_Str ("==== Compiling subprogram spec ");
2314 Write_Name (Chars (Designator));
2315 Write_Str (" from ");
2316 Write_Location (Sloc (N));
2320 New_Overloaded_Entity (Designator);
2321 Check_Delayed_Subprogram (Designator);
2323 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
2326 if Ada_Version >= Ada_05
2327 and then Comes_From_Source (N)
2328 and then Is_Dispatching_Operation (Designator)
2335 if Has_Controlling_Result (Designator) then
2336 Etyp := Etype (Designator);
2339 E := First_Entity (Designator);
2341 and then Is_Formal (E)
2342 and then not Is_Controlling_Formal (E)
2350 if Is_Access_Type (Etyp) then
2351 Etyp := Directly_Designated_Type (Etyp);
2354 if Is_Interface (Etyp)
2355 and then not Is_Abstract_Subprogram (Designator)
2356 and then not (Ekind (Designator) = E_Procedure
2357 and then Null_Present (Specification (N)))
2359 Error_Msg_Name_1 := Chars (Defining_Entity (N));
2361 ("(Ada 2005) interface subprogram % must be abstract or null",
2367 -- What is the following code for, it used to be
2369 -- ??? Set_Suppress_Elaboration_Checks
2370 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
2372 -- The following seems equivalent, but a bit dubious
2374 if Elaboration_Checks_Suppressed (Designator) then
2375 Set_Kill_Elaboration_Checks (Designator);
2378 if Scop /= Standard_Standard
2379 and then not Is_Child_Unit (Designator)
2381 Set_Categorization_From_Scope (Designator, Scop);
2383 -- For a compilation unit, check for library-unit pragmas
2385 Push_Scope (Designator);
2386 Set_Categorization_From_Pragmas (N);
2387 Validate_Categorization_Dependency (N, Designator);
2391 -- For a compilation unit, set body required. This flag will only be
2392 -- reset if a valid Import or Interface pragma is processed later on.
2394 if Nkind (Parent (N)) = N_Compilation_Unit then
2395 Set_Body_Required (Parent (N), True);
2397 if Ada_Version >= Ada_05
2398 and then Nkind (Specification (N)) = N_Procedure_Specification
2399 and then Null_Present (Specification (N))
2402 ("null procedure cannot be declared at library level", N);
2406 Generate_Reference_To_Formals (Designator);
2407 Check_Eliminated (Designator);
2409 -- Ada 2005: if procedure is declared with "is null" qualifier,
2410 -- it requires no body.
2412 if Nkind (Specification (N)) = N_Procedure_Specification
2413 and then Null_Present (Specification (N))
2415 Set_Has_Completion (Designator);
2416 Set_Is_Inlined (Designator);
2418 if Is_Protected_Type (Current_Scope) then
2420 ("protected operation cannot be a null procedure", N);
2423 end Analyze_Subprogram_Declaration;
2425 --------------------------------------
2426 -- Analyze_Subprogram_Specification --
2427 --------------------------------------
2429 -- Reminder: N here really is a subprogram specification (not a subprogram
2430 -- declaration). This procedure is called to analyze the specification in
2431 -- both subprogram bodies and subprogram declarations (specs).
2433 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
2434 Designator : constant Entity_Id := Defining_Entity (N);
2435 Formals : constant List_Id := Parameter_Specifications (N);
2437 Formal_Typ : Entity_Id;
2439 -- Start of processing for Analyze_Subprogram_Specification
2442 Generate_Definition (Designator);
2444 if Nkind (N) = N_Function_Specification then
2445 Set_Ekind (Designator, E_Function);
2446 Set_Mechanism (Designator, Default_Mechanism);
2449 Set_Ekind (Designator, E_Procedure);
2450 Set_Etype (Designator, Standard_Void_Type);
2453 -- Introduce new scope for analysis of the formals and the return type
2455 Set_Scope (Designator, Current_Scope);
2457 if Present (Formals) then
2458 Push_Scope (Designator);
2459 Process_Formals (Formals, N);
2461 -- Ada 2005 (AI-345): Allow the overriding of interface primitives
2462 -- by subprograms which belong to a concurrent type implementing an
2463 -- interface. Set the parameter type of each controlling formal to
2464 -- the corresponding record type.
2466 if Ada_Version >= Ada_05 then
2467 Formal := First_Formal (Designator);
2468 while Present (Formal) loop
2469 Formal_Typ := Etype (Formal);
2471 if (Ekind (Formal_Typ) = E_Protected_Type
2472 or else Ekind (Formal_Typ) = E_Task_Type)
2473 and then Present (Corresponding_Record_Type (Formal_Typ))
2474 and then Present (Abstract_Interfaces
2475 (Corresponding_Record_Type (Formal_Typ)))
2478 Corresponding_Record_Type (Formal_Typ));
2481 Formal := Next_Formal (Formal);
2487 elsif Nkind (N) = N_Function_Specification then
2488 Analyze_Return_Type (N);
2491 if Nkind (N) = N_Function_Specification then
2492 if Nkind (Designator) = N_Defining_Operator_Symbol then
2493 Valid_Operator_Definition (Designator);
2496 May_Need_Actuals (Designator);
2498 -- Ada 2005 (AI-251): In case of primitives associated with abstract
2499 -- interface types the following error message will be reported later
2500 -- (see Analyze_Subprogram_Declaration).
2502 if Is_Abstract_Type (Etype (Designator))
2503 and then not Is_Interface (Etype (Designator))
2504 and then Nkind (Parent (N)) /=
2505 N_Abstract_Subprogram_Declaration
2507 (Nkind (Parent (N))) /= N_Formal_Abstract_Subprogram_Declaration
2509 (Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
2510 or else not Is_Entity_Name (Name (Parent (N)))
2511 or else not Is_Abstract_Subprogram
2512 (Entity (Name (Parent (N)))))
2515 ("function that returns abstract type must be abstract", N);
2520 end Analyze_Subprogram_Specification;
2522 --------------------------
2523 -- Build_Body_To_Inline --
2524 --------------------------
2526 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
2527 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
2528 Original_Body : Node_Id;
2529 Body_To_Analyze : Node_Id;
2530 Max_Size : constant := 10;
2531 Stat_Count : Integer := 0;
2533 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
2534 -- Check for declarations that make inlining not worthwhile
2536 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
2537 -- Check for statements that make inlining not worthwhile: any tasking
2538 -- statement, nested at any level. Keep track of total number of
2539 -- elementary statements, as a measure of acceptable size.
2541 function Has_Pending_Instantiation return Boolean;
2542 -- If some enclosing body contains instantiations that appear before the
2543 -- corresponding generic body, the enclosing body has a freeze node so
2544 -- that it can be elaborated after the generic itself. This might
2545 -- conflict with subsequent inlinings, so that it is unsafe to try to
2546 -- inline in such a case.
2548 function Has_Single_Return return Boolean;
2549 -- In general we cannot inline functions that return unconstrained type.
2550 -- However, we can handle such functions if all return statements return
2551 -- a local variable that is the only declaration in the body of the
2552 -- function. In that case the call can be replaced by that local
2553 -- variable as is done for other inlined calls.
2555 procedure Remove_Pragmas;
2556 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
2557 -- parameter has no meaning when the body is inlined and the formals
2558 -- are rewritten. Remove it from body to inline. The analysis of the
2559 -- non-inlined body will handle the pragma properly.
2561 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
2562 -- If the body of the subprogram includes a call that returns an
2563 -- unconstrained type, the secondary stack is involved, and it
2564 -- is not worth inlining.
2566 ------------------------------
2567 -- Has_Excluded_Declaration --
2568 ------------------------------
2570 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
2573 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
2574 -- Nested subprograms make a given body ineligible for inlining, but
2575 -- we make an exception for instantiations of unchecked conversion.
2576 -- The body has not been analyzed yet, so check the name, and verify
2577 -- that the visible entity with that name is the predefined unit.
2579 -----------------------------
2580 -- Is_Unchecked_Conversion --
2581 -----------------------------
2583 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
2584 Id : constant Node_Id := Name (D);
2588 if Nkind (Id) = N_Identifier
2589 and then Chars (Id) = Name_Unchecked_Conversion
2591 Conv := Current_Entity (Id);
2593 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
2594 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
2596 Conv := Current_Entity (Selector_Name (Id));
2601 return Present (Conv)
2602 and then Is_Predefined_File_Name
2603 (Unit_File_Name (Get_Source_Unit (Conv)))
2604 and then Is_Intrinsic_Subprogram (Conv);
2605 end Is_Unchecked_Conversion;
2607 -- Start of processing for Has_Excluded_Declaration
2611 while Present (D) loop
2612 if (Nkind (D) = N_Function_Instantiation
2613 and then not Is_Unchecked_Conversion (D))
2614 or else Nkind_In (D, N_Protected_Type_Declaration,
2615 N_Package_Declaration,
2616 N_Package_Instantiation,
2618 N_Procedure_Instantiation,
2619 N_Task_Type_Declaration)
2622 ("cannot inline & (non-allowed declaration)?", D, Subp);
2630 end Has_Excluded_Declaration;
2632 ----------------------------
2633 -- Has_Excluded_Statement --
2634 ----------------------------
2636 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
2642 while Present (S) loop
2643 Stat_Count := Stat_Count + 1;
2645 if Nkind_In (S, N_Abort_Statement,
2646 N_Asynchronous_Select,
2647 N_Conditional_Entry_Call,
2648 N_Delay_Relative_Statement,
2649 N_Delay_Until_Statement,
2654 ("cannot inline & (non-allowed statement)?", S, Subp);
2657 elsif Nkind (S) = N_Block_Statement then
2658 if Present (Declarations (S))
2659 and then Has_Excluded_Declaration (Declarations (S))
2663 elsif Present (Handled_Statement_Sequence (S))
2666 (Exception_Handlers (Handled_Statement_Sequence (S)))
2668 Has_Excluded_Statement
2669 (Statements (Handled_Statement_Sequence (S))))
2674 elsif Nkind (S) = N_Case_Statement then
2675 E := First (Alternatives (S));
2676 while Present (E) loop
2677 if Has_Excluded_Statement (Statements (E)) then
2684 elsif Nkind (S) = N_If_Statement then
2685 if Has_Excluded_Statement (Then_Statements (S)) then
2689 if Present (Elsif_Parts (S)) then
2690 E := First (Elsif_Parts (S));
2691 while Present (E) loop
2692 if Has_Excluded_Statement (Then_Statements (E)) then
2699 if Present (Else_Statements (S))
2700 and then Has_Excluded_Statement (Else_Statements (S))
2705 elsif Nkind (S) = N_Loop_Statement
2706 and then Has_Excluded_Statement (Statements (S))
2715 end Has_Excluded_Statement;
2717 -------------------------------
2718 -- Has_Pending_Instantiation --
2719 -------------------------------
2721 function Has_Pending_Instantiation return Boolean is
2726 while Present (S) loop
2727 if Is_Compilation_Unit (S)
2728 or else Is_Child_Unit (S)
2731 elsif Ekind (S) = E_Package
2732 and then Has_Forward_Instantiation (S)
2741 end Has_Pending_Instantiation;
2743 ------------------------
2744 -- Has_Single_Return --
2745 ------------------------
2747 function Has_Single_Return return Boolean is
2748 Return_Statement : Node_Id := Empty;
2750 function Check_Return (N : Node_Id) return Traverse_Result;
2756 function Check_Return (N : Node_Id) return Traverse_Result is
2758 if Nkind (N) = N_Simple_Return_Statement then
2759 if Present (Expression (N))
2760 and then Is_Entity_Name (Expression (N))
2762 if No (Return_Statement) then
2763 Return_Statement := N;
2766 elsif Chars (Expression (N)) =
2767 Chars (Expression (Return_Statement))
2776 -- Expression has wrong form
2786 function Check_All_Returns is new Traverse_Func (Check_Return);
2788 -- Start of processing for Has_Single_Return
2791 return Check_All_Returns (N) = OK
2792 and then Present (Declarations (N))
2793 and then Present (First (Declarations (N)))
2794 and then Chars (Expression (Return_Statement)) =
2795 Chars (Defining_Identifier (First (Declarations (N))));
2796 end Has_Single_Return;
2798 --------------------
2799 -- Remove_Pragmas --
2800 --------------------
2802 procedure Remove_Pragmas is
2807 Decl := First (Declarations (Body_To_Analyze));
2808 while Present (Decl) loop
2811 if Nkind (Decl) = N_Pragma
2812 and then (Pragma_Name (Decl) = Name_Unreferenced
2814 Pragma_Name (Decl) = Name_Unmodified)
2823 --------------------------
2824 -- Uses_Secondary_Stack --
2825 --------------------------
2827 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
2828 function Check_Call (N : Node_Id) return Traverse_Result;
2829 -- Look for function calls that return an unconstrained type
2835 function Check_Call (N : Node_Id) return Traverse_Result is
2837 if Nkind (N) = N_Function_Call
2838 and then Is_Entity_Name (Name (N))
2839 and then Is_Composite_Type (Etype (Entity (Name (N))))
2840 and then not Is_Constrained (Etype (Entity (Name (N))))
2843 ("cannot inline & (call returns unconstrained type)?",
2851 function Check_Calls is new Traverse_Func (Check_Call);
2854 return Check_Calls (Bod) = Abandon;
2855 end Uses_Secondary_Stack;
2857 -- Start of processing for Build_Body_To_Inline
2860 if Nkind (Decl) = N_Subprogram_Declaration
2861 and then Present (Body_To_Inline (Decl))
2863 return; -- Done already.
2865 -- Functions that return unconstrained composite types require
2866 -- secondary stack handling, and cannot currently be inlined, unless
2867 -- all return statements return a local variable that is the first
2868 -- local declaration in the body.
2870 elsif Ekind (Subp) = E_Function
2871 and then not Is_Scalar_Type (Etype (Subp))
2872 and then not Is_Access_Type (Etype (Subp))
2873 and then not Is_Constrained (Etype (Subp))
2875 if not Has_Single_Return then
2877 ("cannot inline & (unconstrained return type)?", N, Subp);
2881 -- Ditto for functions that return controlled types, where controlled
2882 -- actions interfere in complex ways with inlining.
2884 elsif Ekind (Subp) = E_Function
2885 and then Controlled_Type (Etype (Subp))
2888 ("cannot inline & (controlled return type)?", N, Subp);
2892 if Present (Declarations (N))
2893 and then Has_Excluded_Declaration (Declarations (N))
2898 if Present (Handled_Statement_Sequence (N)) then
2899 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
2901 ("cannot inline& (exception handler)?",
2902 First (Exception_Handlers (Handled_Statement_Sequence (N))),
2906 Has_Excluded_Statement
2907 (Statements (Handled_Statement_Sequence (N)))
2913 -- We do not inline a subprogram that is too large, unless it is
2914 -- marked Inline_Always. This pragma does not suppress the other
2915 -- checks on inlining (forbidden declarations, handlers, etc).
2917 if Stat_Count > Max_Size
2918 and then not Has_Pragma_Inline_Always (Subp)
2920 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
2924 if Has_Pending_Instantiation then
2926 ("cannot inline& (forward instance within enclosing body)?",
2931 -- Within an instance, the body to inline must be treated as a nested
2932 -- generic, so that the proper global references are preserved.
2934 -- Note that we do not do this at the library level, because it is not
2935 -- needed, and furthermore this causes trouble if front end inlining
2936 -- is activated (-gnatN).
2938 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
2939 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
2940 Original_Body := Copy_Generic_Node (N, Empty, True);
2942 Original_Body := Copy_Separate_Tree (N);
2945 -- We need to capture references to the formals in order to substitute
2946 -- the actuals at the point of inlining, i.e. instantiation. To treat
2947 -- the formals as globals to the body to inline, we nest it within
2948 -- a dummy parameterless subprogram, declared within the real one.
2949 -- To avoid generating an internal name (which is never public, and
2950 -- which affects serial numbers of other generated names), we use
2951 -- an internal symbol that cannot conflict with user declarations.
2953 Set_Parameter_Specifications (Specification (Original_Body), No_List);
2954 Set_Defining_Unit_Name
2955 (Specification (Original_Body),
2956 Make_Defining_Identifier (Sloc (N), Name_uParent));
2957 Set_Corresponding_Spec (Original_Body, Empty);
2959 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
2961 -- Set return type of function, which is also global and does not need
2964 if Ekind (Subp) = E_Function then
2965 Set_Result_Definition (Specification (Body_To_Analyze),
2966 New_Occurrence_Of (Etype (Subp), Sloc (N)));
2969 if No (Declarations (N)) then
2970 Set_Declarations (N, New_List (Body_To_Analyze));
2972 Append (Body_To_Analyze, Declarations (N));
2975 Expander_Mode_Save_And_Set (False);
2978 Analyze (Body_To_Analyze);
2979 Push_Scope (Defining_Entity (Body_To_Analyze));
2980 Save_Global_References (Original_Body);
2982 Remove (Body_To_Analyze);
2984 Expander_Mode_Restore;
2986 -- Restore environment if previously saved
2988 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
2992 -- If secondary stk used there is no point in inlining. We have
2993 -- already issued the warning in this case, so nothing to do.
2995 if Uses_Secondary_Stack (Body_To_Analyze) then
2999 Set_Body_To_Inline (Decl, Original_Body);
3000 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3001 Set_Is_Inlined (Subp);
3002 end Build_Body_To_Inline;
3008 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3010 -- Do not emit warning if this is a predefined unit which is not
3011 -- the main unit. With validity checks enabled, some predefined
3012 -- subprograms may contain nested subprograms and become ineligible
3015 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3016 and then not In_Extended_Main_Source_Unit (Subp)
3020 elsif Has_Pragma_Inline_Always (Subp) then
3022 -- Remove last character (question mark) to make this into an error,
3023 -- because the Inline_Always pragma cannot be obeyed.
3025 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3027 elsif Ineffective_Inline_Warnings then
3028 Error_Msg_NE (Msg, N, Subp);
3032 -----------------------
3033 -- Check_Conformance --
3034 -----------------------
3036 procedure Check_Conformance
3037 (New_Id : Entity_Id;
3039 Ctype : Conformance_Type;
3041 Conforms : out Boolean;
3042 Err_Loc : Node_Id := Empty;
3043 Get_Inst : Boolean := False;
3044 Skip_Controlling_Formals : Boolean := False)
3046 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3047 -- Post error message for conformance error on given node. Two messages
3048 -- are output. The first points to the previous declaration with a
3049 -- general "no conformance" message. The second is the detailed reason,
3050 -- supplied as Msg. The parameter N provide information for a possible
3051 -- & insertion in the message, and also provides the location for
3052 -- posting the message in the absence of a specified Err_Loc location.
3054 -----------------------
3055 -- Conformance_Error --
3056 -----------------------
3058 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3065 if No (Err_Loc) then
3071 Error_Msg_Sloc := Sloc (Old_Id);
3074 when Type_Conformant =>
3076 ("not type conformant with declaration#!", Enode);
3078 when Mode_Conformant =>
3079 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3081 ("not mode conformant with operation inherited#!",
3085 ("not mode conformant with declaration#!", Enode);
3088 when Subtype_Conformant =>
3089 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3091 ("not subtype conformant with operation inherited#!",
3095 ("not subtype conformant with declaration#!", Enode);
3098 when Fully_Conformant =>
3099 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3101 ("not fully conformant with operation inherited#!",
3105 ("not fully conformant with declaration#!", Enode);
3109 Error_Msg_NE (Msg, Enode, N);
3111 end Conformance_Error;
3115 Old_Type : constant Entity_Id := Etype (Old_Id);
3116 New_Type : constant Entity_Id := Etype (New_Id);
3117 Old_Formal : Entity_Id;
3118 New_Formal : Entity_Id;
3119 Access_Types_Match : Boolean;
3120 Old_Formal_Base : Entity_Id;
3121 New_Formal_Base : Entity_Id;
3123 -- Start of processing for Check_Conformance
3128 -- We need a special case for operators, since they don't appear
3131 if Ctype = Type_Conformant then
3132 if Ekind (New_Id) = E_Operator
3133 and then Operator_Matches_Spec (New_Id, Old_Id)
3139 -- If both are functions/operators, check return types conform
3141 if Old_Type /= Standard_Void_Type
3142 and then New_Type /= Standard_Void_Type
3144 if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3145 Conformance_Error ("\return type does not match!", New_Id);
3149 -- Ada 2005 (AI-231): In case of anonymous access types check the
3150 -- null-exclusion and access-to-constant attributes match.
3152 if Ada_Version >= Ada_05
3153 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3155 (Can_Never_Be_Null (Old_Type)
3156 /= Can_Never_Be_Null (New_Type)
3157 or else Is_Access_Constant (Etype (Old_Type))
3158 /= Is_Access_Constant (Etype (New_Type)))
3160 Conformance_Error ("\return type does not match!", New_Id);
3164 -- If either is a function/operator and the other isn't, error
3166 elsif Old_Type /= Standard_Void_Type
3167 or else New_Type /= Standard_Void_Type
3169 Conformance_Error ("\functions can only match functions!", New_Id);
3173 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
3174 -- If this is a renaming as body, refine error message to indicate that
3175 -- the conflict is with the original declaration. If the entity is not
3176 -- frozen, the conventions don't have to match, the one of the renamed
3177 -- entity is inherited.
3179 if Ctype >= Subtype_Conformant then
3180 if Convention (Old_Id) /= Convention (New_Id) then
3182 if not Is_Frozen (New_Id) then
3185 elsif Present (Err_Loc)
3186 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
3187 and then Present (Corresponding_Spec (Err_Loc))
3189 Error_Msg_Name_1 := Chars (New_Id);
3191 Name_Ada + Convention_Id'Pos (Convention (New_Id));
3193 Conformance_Error ("\prior declaration for% has convention %!");
3196 Conformance_Error ("\calling conventions do not match!");
3201 elsif Is_Formal_Subprogram (Old_Id)
3202 or else Is_Formal_Subprogram (New_Id)
3204 Conformance_Error ("\formal subprograms not allowed!");
3209 -- Deal with parameters
3211 -- Note: we use the entity information, rather than going directly
3212 -- to the specification in the tree. This is not only simpler, but
3213 -- absolutely necessary for some cases of conformance tests between
3214 -- operators, where the declaration tree simply does not exist!
3216 Old_Formal := First_Formal (Old_Id);
3217 New_Formal := First_Formal (New_Id);
3219 while Present (Old_Formal) and then Present (New_Formal) loop
3220 if Is_Controlling_Formal (Old_Formal)
3221 and then Is_Controlling_Formal (New_Formal)
3222 and then Skip_Controlling_Formals
3224 goto Skip_Controlling_Formal;
3227 if Ctype = Fully_Conformant then
3229 -- Names must match. Error message is more accurate if we do
3230 -- this before checking that the types of the formals match.
3232 if Chars (Old_Formal) /= Chars (New_Formal) then
3233 Conformance_Error ("\name & does not match!", New_Formal);
3235 -- Set error posted flag on new formal as well to stop
3236 -- junk cascaded messages in some cases.
3238 Set_Error_Posted (New_Formal);
3243 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
3244 -- case occurs whenever a subprogram is being renamed and one of its
3245 -- parameters imposes a null exclusion. For example:
3247 -- type T is null record;
3248 -- type Acc_T is access T;
3249 -- subtype Acc_T_Sub is Acc_T;
3251 -- procedure P (Obj : not null Acc_T_Sub); -- itype
3252 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
3255 Old_Formal_Base := Etype (Old_Formal);
3256 New_Formal_Base := Etype (New_Formal);
3259 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
3260 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
3263 Access_Types_Match := Ada_Version >= Ada_05
3265 -- Ensure that this rule is only applied when New_Id is a
3266 -- renaming of Old_Id.
3268 and then Nkind (Parent (Parent (New_Id))) =
3269 N_Subprogram_Renaming_Declaration
3270 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
3271 and then Present (Entity (Name (Parent (Parent (New_Id)))))
3272 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
3274 -- Now handle the allowed access-type case
3276 and then Is_Access_Type (Old_Formal_Base)
3277 and then Is_Access_Type (New_Formal_Base)
3279 -- The type kinds must match. The only exception occurs with
3280 -- multiple generics of the form:
3283 -- type F is private; type A is private;
3284 -- type F_Ptr is access F; type A_Ptr is access A;
3285 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
3286 -- package F_Pack is ... package A_Pack is
3287 -- package F_Inst is
3288 -- new F_Pack (A, A_Ptr, A_P);
3290 -- When checking for conformance between the parameters of A_P
3291 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
3292 -- because the compiler has transformed A_Ptr into a subtype of
3293 -- F_Ptr. We catch this case in the code below.
3295 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
3297 (Is_Generic_Type (Old_Formal_Base)
3298 and then Is_Generic_Type (New_Formal_Base)
3299 and then Is_Internal (New_Formal_Base)
3300 and then Etype (Etype (New_Formal_Base)) =
3302 and then Directly_Designated_Type (Old_Formal_Base) =
3303 Directly_Designated_Type (New_Formal_Base)
3304 and then ((Is_Itype (Old_Formal_Base)
3305 and then Can_Never_Be_Null (Old_Formal_Base))
3307 (Is_Itype (New_Formal_Base)
3308 and then Can_Never_Be_Null (New_Formal_Base)));
3310 -- Types must always match. In the visible part of an instance,
3311 -- usual overloading rules for dispatching operations apply, and
3312 -- we check base types (not the actual subtypes).
3314 if In_Instance_Visible_Part
3315 and then Is_Dispatching_Operation (New_Id)
3317 if not Conforming_Types
3318 (T1 => Base_Type (Etype (Old_Formal)),
3319 T2 => Base_Type (Etype (New_Formal)),
3321 Get_Inst => Get_Inst)
3322 and then not Access_Types_Match
3324 Conformance_Error ("\type of & does not match!", New_Formal);
3328 elsif not Conforming_Types
3329 (T1 => Old_Formal_Base,
3330 T2 => New_Formal_Base,
3332 Get_Inst => Get_Inst)
3333 and then not Access_Types_Match
3335 Conformance_Error ("\type of & does not match!", New_Formal);
3339 -- For mode conformance, mode must match
3341 if Ctype >= Mode_Conformant then
3342 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
3343 Conformance_Error ("\mode of & does not match!", New_Formal);
3346 -- Part of mode conformance for access types is having the same
3347 -- constant modifier.
3349 elsif Access_Types_Match
3350 and then Is_Access_Constant (Old_Formal_Base) /=
3351 Is_Access_Constant (New_Formal_Base)
3354 ("\constant modifier does not match!", New_Formal);
3359 if Ctype >= Subtype_Conformant then
3361 -- Ada 2005 (AI-231): In case of anonymous access types check
3362 -- the null-exclusion and access-to-constant attributes must
3365 if Ada_Version >= Ada_05
3366 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
3367 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
3369 (Can_Never_Be_Null (Old_Formal) /=
3370 Can_Never_Be_Null (New_Formal)
3372 Is_Access_Constant (Etype (Old_Formal)) /=
3373 Is_Access_Constant (Etype (New_Formal)))
3375 -- It is allowed to omit the null-exclusion in case of stream
3376 -- attribute subprograms. We recognize stream subprograms
3377 -- through their TSS-generated suffix.
3380 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
3382 if TSS_Name /= TSS_Stream_Read
3383 and then TSS_Name /= TSS_Stream_Write
3384 and then TSS_Name /= TSS_Stream_Input
3385 and then TSS_Name /= TSS_Stream_Output
3388 ("\type of & does not match!", New_Formal);
3395 -- Full conformance checks
3397 if Ctype = Fully_Conformant then
3399 -- We have checked already that names match
3401 if Parameter_Mode (Old_Formal) = E_In_Parameter then
3403 -- Check default expressions for in parameters
3406 NewD : constant Boolean :=
3407 Present (Default_Value (New_Formal));
3408 OldD : constant Boolean :=
3409 Present (Default_Value (Old_Formal));
3411 if NewD or OldD then
3413 -- The old default value has been analyzed because the
3414 -- current full declaration will have frozen everything
3415 -- before. The new default value has not been analyzed,
3416 -- so analyze it now before we check for conformance.
3419 Push_Scope (New_Id);
3420 Preanalyze_Spec_Expression
3421 (Default_Value (New_Formal), Etype (New_Formal));
3425 if not (NewD and OldD)
3426 or else not Fully_Conformant_Expressions
3427 (Default_Value (Old_Formal),
3428 Default_Value (New_Formal))
3431 ("\default expression for & does not match!",
3440 -- A couple of special checks for Ada 83 mode. These checks are
3441 -- skipped if either entity is an operator in package Standard,
3442 -- or if either old or new instance is not from the source program.
3444 if Ada_Version = Ada_83
3445 and then Sloc (Old_Id) > Standard_Location
3446 and then Sloc (New_Id) > Standard_Location
3447 and then Comes_From_Source (Old_Id)
3448 and then Comes_From_Source (New_Id)
3451 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
3452 New_Param : constant Node_Id := Declaration_Node (New_Formal);
3455 -- Explicit IN must be present or absent in both cases. This
3456 -- test is required only in the full conformance case.
3458 if In_Present (Old_Param) /= In_Present (New_Param)
3459 and then Ctype = Fully_Conformant
3462 ("\(Ada 83) IN must appear in both declarations",
3467 -- Grouping (use of comma in param lists) must be the same
3468 -- This is where we catch a misconformance like:
3471 -- A : Integer; B : Integer
3473 -- which are represented identically in the tree except
3474 -- for the setting of the flags More_Ids and Prev_Ids.
3476 if More_Ids (Old_Param) /= More_Ids (New_Param)
3477 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
3480 ("\grouping of & does not match!", New_Formal);
3486 -- This label is required when skipping controlling formals
3488 <<Skip_Controlling_Formal>>
3490 Next_Formal (Old_Formal);
3491 Next_Formal (New_Formal);
3494 if Present (Old_Formal) then
3495 Conformance_Error ("\too few parameters!");
3498 elsif Present (New_Formal) then
3499 Conformance_Error ("\too many parameters!", New_Formal);
3502 end Check_Conformance;
3504 -----------------------
3505 -- Check_Conventions --
3506 -----------------------
3508 procedure Check_Conventions (Typ : Entity_Id) is
3510 function Skip_Check (Op : Entity_Id) return Boolean;
3511 pragma Inline (Skip_Check);
3512 -- A small optimization: skip the predefined dispatching operations,
3513 -- since they always have the same convention. Also do not consider
3514 -- abstract primitives since those are left by an erroneous overriding.
3515 -- This function returns True for any operation that is thus exempted
3516 -- exempted from checking.
3518 procedure Check_Convention
3520 Search_From : Elmt_Id);
3521 -- Verify that the convention of inherited dispatching operation Op is
3522 -- consistent among all subprograms it overrides. In order to minimize
3523 -- the search, Search_From is utilized to designate a specific point in
3524 -- the list rather than iterating over the whole list once more.
3526 ----------------------
3527 -- Check_Convention --
3528 ----------------------
3530 procedure Check_Convention
3532 Search_From : Elmt_Id)
3534 procedure Error_Msg_Operation (Op : Entity_Id);
3535 -- Emit a continuation to an error message depicting the kind, name,
3536 -- convention and source location of subprogram Op.
3538 -------------------------
3539 -- Error_Msg_Operation --
3540 -------------------------
3542 procedure Error_Msg_Operation (Op : Entity_Id) is
3544 Error_Msg_Name_1 := Chars (Op);
3546 -- Error messages of primitive subprograms do not contain a
3547 -- convention attribute since the convention may have been first
3548 -- inherited from a parent subprogram, then changed by a pragma.
3550 if Comes_From_Source (Op) then
3551 Error_Msg_Sloc := Sloc (Op);
3553 ("\ primitive % defined #", Typ);
3556 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
3558 if Present (Abstract_Interface_Alias (Op)) then
3559 Error_Msg_Sloc := Sloc (Abstract_Interface_Alias (Op));
3560 Error_Msg_N ("\\overridden operation % with " &
3561 "convention % defined #", Typ);
3563 else pragma Assert (Present (Alias (Op)));
3564 Error_Msg_Sloc := Sloc (Alias (Op));
3565 Error_Msg_N ("\\inherited operation % with " &
3566 "convention % defined #", Typ);
3569 end Error_Msg_Operation;
3573 Second_Prim_Op : Entity_Id;
3574 Second_Prim_Op_Elmt : Elmt_Id;
3576 -- Start of processing for Check_Convention
3579 Second_Prim_Op_Elmt := Next_Elmt (Search_From);
3580 while Present (Second_Prim_Op_Elmt) loop
3581 Second_Prim_Op := Node (Second_Prim_Op_Elmt);
3583 if not Skip_Check (Second_Prim_Op)
3584 and then Chars (Second_Prim_Op) = Chars (Op)
3585 and then Type_Conformant (Second_Prim_Op, Op)
3586 and then Convention (Second_Prim_Op) /= Convention (Op)
3589 ("inconsistent conventions in primitive operations", Typ);
3591 Error_Msg_Operation (Op);
3592 Error_Msg_Operation (Second_Prim_Op);
3594 -- Avoid cascading errors
3599 Next_Elmt (Second_Prim_Op_Elmt);
3601 end Check_Convention;
3607 function Skip_Check (Op : Entity_Id) return Boolean is
3609 return Is_Predefined_Dispatching_Operation (Op)
3610 or else Is_Abstract_Subprogram (Op);
3615 Prim_Op : Entity_Id;
3616 Prim_Op_Elmt : Elmt_Id;
3618 -- Start of processing for Check_Conventions
3621 -- The algorithm checks every overriding dispatching operation against
3622 -- all the corresponding overridden dispatching operations, detecting
3623 -- differences in conventions.
3625 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
3626 while Present (Prim_Op_Elmt) loop
3627 Prim_Op := Node (Prim_Op_Elmt);
3629 -- A small optimization: skip the predefined dispatching operations
3630 -- since they always have the same convention. Also avoid processing
3631 -- of abstract primitives left from an erroneous overriding.
3633 if not Skip_Check (Prim_Op) then
3636 Search_From => Prim_Op_Elmt);
3639 Next_Elmt (Prim_Op_Elmt);
3641 end Check_Conventions;
3643 ------------------------------
3644 -- Check_Delayed_Subprogram --
3645 ------------------------------
3647 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
3650 procedure Possible_Freeze (T : Entity_Id);
3651 -- T is the type of either a formal parameter or of the return type.
3652 -- If T is not yet frozen and needs a delayed freeze, then the
3653 -- subprogram itself must be delayed.
3655 ---------------------
3656 -- Possible_Freeze --
3657 ---------------------
3659 procedure Possible_Freeze (T : Entity_Id) is
3661 if Has_Delayed_Freeze (T)
3662 and then not Is_Frozen (T)
3664 Set_Has_Delayed_Freeze (Designator);
3666 elsif Is_Access_Type (T)
3667 and then Has_Delayed_Freeze (Designated_Type (T))
3668 and then not Is_Frozen (Designated_Type (T))
3670 Set_Has_Delayed_Freeze (Designator);
3672 end Possible_Freeze;
3674 -- Start of processing for Check_Delayed_Subprogram
3677 -- Never need to freeze abstract subprogram
3679 if Ekind (Designator) /= E_Subprogram_Type
3680 and then Is_Abstract_Subprogram (Designator)
3684 -- Need delayed freeze if return type itself needs a delayed
3685 -- freeze and is not yet frozen.
3687 Possible_Freeze (Etype (Designator));
3688 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
3690 -- Need delayed freeze if any of the formal types themselves need
3691 -- a delayed freeze and are not yet frozen.
3693 F := First_Formal (Designator);
3694 while Present (F) loop
3695 Possible_Freeze (Etype (F));
3696 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
3701 -- Mark functions that return by reference. Note that it cannot be
3702 -- done for delayed_freeze subprograms because the underlying
3703 -- returned type may not be known yet (for private types)
3705 if not Has_Delayed_Freeze (Designator)
3706 and then Expander_Active
3709 Typ : constant Entity_Id := Etype (Designator);
3710 Utyp : constant Entity_Id := Underlying_Type (Typ);
3713 if Is_Inherently_Limited_Type (Typ) then
3714 Set_Returns_By_Ref (Designator);
3716 elsif Present (Utyp) and then CW_Or_Controlled_Type (Utyp) then
3717 Set_Returns_By_Ref (Designator);
3721 end Check_Delayed_Subprogram;
3723 ------------------------------------
3724 -- Check_Discriminant_Conformance --
3725 ------------------------------------
3727 procedure Check_Discriminant_Conformance
3732 Old_Discr : Entity_Id := First_Discriminant (Prev);
3733 New_Discr : Node_Id := First (Discriminant_Specifications (N));
3734 New_Discr_Id : Entity_Id;
3735 New_Discr_Type : Entity_Id;
3737 procedure Conformance_Error (Msg : String; N : Node_Id);
3738 -- Post error message for conformance error on given node. Two messages
3739 -- are output. The first points to the previous declaration with a
3740 -- general "no conformance" message. The second is the detailed reason,
3741 -- supplied as Msg. The parameter N provide information for a possible
3742 -- & insertion in the message.
3744 -----------------------
3745 -- Conformance_Error --
3746 -----------------------
3748 procedure Conformance_Error (Msg : String; N : Node_Id) is
3750 Error_Msg_Sloc := Sloc (Prev_Loc);
3751 Error_Msg_N ("not fully conformant with declaration#!", N);
3752 Error_Msg_NE (Msg, N, N);
3753 end Conformance_Error;
3755 -- Start of processing for Check_Discriminant_Conformance
3758 while Present (Old_Discr) and then Present (New_Discr) loop
3760 New_Discr_Id := Defining_Identifier (New_Discr);
3762 -- The subtype mark of the discriminant on the full type has not
3763 -- been analyzed so we do it here. For an access discriminant a new
3766 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
3768 Access_Definition (N, Discriminant_Type (New_Discr));
3771 Analyze (Discriminant_Type (New_Discr));
3772 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
3775 if not Conforming_Types
3776 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
3778 Conformance_Error ("type of & does not match!", New_Discr_Id);
3781 -- Treat the new discriminant as an occurrence of the old one,
3782 -- for navigation purposes, and fill in some semantic
3783 -- information, for completeness.
3785 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
3786 Set_Etype (New_Discr_Id, Etype (Old_Discr));
3787 Set_Scope (New_Discr_Id, Scope (Old_Discr));
3792 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
3793 Conformance_Error ("name & does not match!", New_Discr_Id);
3797 -- Default expressions must match
3800 NewD : constant Boolean :=
3801 Present (Expression (New_Discr));
3802 OldD : constant Boolean :=
3803 Present (Expression (Parent (Old_Discr)));
3806 if NewD or OldD then
3808 -- The old default value has been analyzed and expanded,
3809 -- because the current full declaration will have frozen
3810 -- everything before. The new default values have not been
3811 -- expanded, so expand now to check conformance.
3814 Preanalyze_Spec_Expression
3815 (Expression (New_Discr), New_Discr_Type);
3818 if not (NewD and OldD)
3819 or else not Fully_Conformant_Expressions
3820 (Expression (Parent (Old_Discr)),
3821 Expression (New_Discr))
3825 ("default expression for & does not match!",
3832 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
3834 if Ada_Version = Ada_83 then
3836 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
3839 -- Grouping (use of comma in param lists) must be the same
3840 -- This is where we catch a misconformance like:
3843 -- A : Integer; B : Integer
3845 -- which are represented identically in the tree except
3846 -- for the setting of the flags More_Ids and Prev_Ids.
3848 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
3849 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
3852 ("grouping of & does not match!", New_Discr_Id);
3858 Next_Discriminant (Old_Discr);
3862 if Present (Old_Discr) then
3863 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
3866 elsif Present (New_Discr) then
3868 ("too many discriminants!", Defining_Identifier (New_Discr));
3871 end Check_Discriminant_Conformance;
3873 ----------------------------
3874 -- Check_Fully_Conformant --
3875 ----------------------------
3877 procedure Check_Fully_Conformant
3878 (New_Id : Entity_Id;
3880 Err_Loc : Node_Id := Empty)
3883 pragma Warnings (Off, Result);
3886 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
3887 end Check_Fully_Conformant;
3889 ---------------------------
3890 -- Check_Mode_Conformant --
3891 ---------------------------
3893 procedure Check_Mode_Conformant
3894 (New_Id : Entity_Id;
3896 Err_Loc : Node_Id := Empty;
3897 Get_Inst : Boolean := False)
3900 pragma Warnings (Off, Result);
3903 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
3904 end Check_Mode_Conformant;
3906 --------------------------------
3907 -- Check_Overriding_Indicator --
3908 --------------------------------
3910 procedure Check_Overriding_Indicator
3912 Overridden_Subp : Entity_Id;
3913 Is_Primitive : Boolean)
3919 -- No overriding indicator for literals
3921 if Ekind (Subp) = E_Enumeration_Literal then
3924 elsif Ekind (Subp) = E_Entry then
3925 Decl := Parent (Subp);
3928 Decl := Unit_Declaration_Node (Subp);
3931 if Nkind_In (Decl, N_Subprogram_Body,
3932 N_Subprogram_Body_Stub,
3933 N_Subprogram_Declaration,
3934 N_Abstract_Subprogram_Declaration,
3935 N_Subprogram_Renaming_Declaration)
3937 Spec := Specification (Decl);
3939 elsif Nkind (Decl) = N_Entry_Declaration then
3946 if Present (Overridden_Subp) then
3947 if Must_Not_Override (Spec) then
3948 Error_Msg_Sloc := Sloc (Overridden_Subp);
3950 if Ekind (Subp) = E_Entry then
3952 ("entry & overrides inherited operation #", Spec, Subp);
3955 ("subprogram & overrides inherited operation #", Spec, Subp);
3958 elsif Is_Subprogram (Subp) then
3959 Set_Is_Overriding_Operation (Subp);
3962 -- If Subp is an operator, it may override a predefined operation.
3963 -- In that case overridden_subp is empty because of our implicit
3964 -- representation for predefined operators. We have to check whether the
3965 -- signature of Subp matches that of a predefined operator. Note that
3966 -- first argument provides the name of the operator, and the second
3967 -- argument the signature that may match that of a standard operation.
3968 -- If the indicator is overriding, then the operator must match a
3969 -- predefined signature, because we know already that there is no
3970 -- explicit overridden operation.
3972 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
3974 if Must_Not_Override (Spec) then
3975 if not Is_Primitive then
3977 ("overriding indicator only allowed "
3978 & "if subprogram is primitive", Subp);
3980 elsif Operator_Matches_Spec (Subp, Subp) then
3982 ("subprogram & overrides predefined operator ", Spec, Subp);
3985 elsif Is_Overriding_Operation (Subp) then
3988 elsif Must_Override (Spec) then
3989 if not Operator_Matches_Spec (Subp, Subp) then
3990 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
3993 Set_Is_Overriding_Operation (Subp);
3997 elsif Must_Override (Spec) then
3998 if Ekind (Subp) = E_Entry then
3999 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
4001 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
4004 -- If the operation is marked "not overriding" and it's not primitive
4005 -- then an error is issued, unless this is an operation of a task or
4006 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
4007 -- has been specified have already been checked above.
4009 elsif Must_Not_Override (Spec)
4010 and then not Is_Primitive
4011 and then Ekind (Subp) /= E_Entry
4012 and then Ekind (Scope (Subp)) /= E_Protected_Type
4015 ("overriding indicator only allowed if subprogram is primitive",
4019 end Check_Overriding_Indicator;
4025 -- Note: this procedure needs to know far too much about how the expander
4026 -- messes with exceptions. The use of the flag Exception_Junk and the
4027 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
4028 -- works, but is not very clean. It would be better if the expansion
4029 -- routines would leave Original_Node working nicely, and we could use
4030 -- Original_Node here to ignore all the peculiar expander messing ???
4032 procedure Check_Returns
4036 Proc : Entity_Id := Empty)
4040 procedure Check_Statement_Sequence (L : List_Id);
4041 -- Internal recursive procedure to check a list of statements for proper
4042 -- termination by a return statement (or a transfer of control or a
4043 -- compound statement that is itself internally properly terminated).
4045 ------------------------------
4046 -- Check_Statement_Sequence --
4047 ------------------------------
4049 procedure Check_Statement_Sequence (L : List_Id) is
4054 Raise_Exception_Call : Boolean;
4055 -- Set True if statement sequence terminated by Raise_Exception call
4056 -- or a Reraise_Occurrence call.
4059 Raise_Exception_Call := False;
4061 -- Get last real statement
4063 Last_Stm := Last (L);
4065 -- Deal with digging out exception handler statement sequences that
4066 -- have been transformed by the local raise to goto optimization.
4067 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
4068 -- optimization has occurred, we are looking at something like:
4071 -- original stmts in block
4075 -- goto L1; | omitted if No_Exception_Propagation
4080 -- goto L3; -- skip handler when exception not raised
4082 -- <<L1>> -- target label for local exception
4096 -- and what we have to do is to dig out the estmts1 and estmts2
4097 -- sequences (which were the original sequences of statements in
4098 -- the exception handlers) and check them.
4100 if Nkind (Last_Stm) = N_Label
4101 and then Exception_Junk (Last_Stm)
4107 exit when Nkind (Stm) /= N_Block_Statement;
4108 exit when not Exception_Junk (Stm);
4111 exit when Nkind (Stm) /= N_Label;
4112 exit when not Exception_Junk (Stm);
4113 Check_Statement_Sequence
4114 (Statements (Handled_Statement_Sequence (Next (Stm))));
4119 exit when Nkind (Stm) /= N_Goto_Statement;
4120 exit when not Exception_Junk (Stm);
4124 -- Don't count pragmas
4126 while Nkind (Last_Stm) = N_Pragma
4128 -- Don't count call to SS_Release (can happen after Raise_Exception)
4131 (Nkind (Last_Stm) = N_Procedure_Call_Statement
4133 Nkind (Name (Last_Stm)) = N_Identifier
4135 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
4137 -- Don't count exception junk
4140 (Nkind_In (Last_Stm, N_Goto_Statement,
4142 N_Object_Declaration)
4143 and then Exception_Junk (Last_Stm))
4144 or else Nkind (Last_Stm) in N_Push_xxx_Label
4145 or else Nkind (Last_Stm) in N_Pop_xxx_Label
4150 -- Here we have the "real" last statement
4152 Kind := Nkind (Last_Stm);
4154 -- Transfer of control, OK. Note that in the No_Return procedure
4155 -- case, we already diagnosed any explicit return statements, so
4156 -- we can treat them as OK in this context.
4158 if Is_Transfer (Last_Stm) then
4161 -- Check cases of explicit non-indirect procedure calls
4163 elsif Kind = N_Procedure_Call_Statement
4164 and then Is_Entity_Name (Name (Last_Stm))
4166 -- Check call to Raise_Exception procedure which is treated
4167 -- specially, as is a call to Reraise_Occurrence.
4169 -- We suppress the warning in these cases since it is likely that
4170 -- the programmer really does not expect to deal with the case
4171 -- of Null_Occurrence, and thus would find a warning about a
4172 -- missing return curious, and raising Program_Error does not
4173 -- seem such a bad behavior if this does occur.
4175 -- Note that in the Ada 2005 case for Raise_Exception, the actual
4176 -- behavior will be to raise Constraint_Error (see AI-329).
4178 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
4180 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
4182 Raise_Exception_Call := True;
4184 -- For Raise_Exception call, test first argument, if it is
4185 -- an attribute reference for a 'Identity call, then we know
4186 -- that the call cannot possibly return.
4189 Arg : constant Node_Id :=
4190 Original_Node (First_Actual (Last_Stm));
4192 if Nkind (Arg) = N_Attribute_Reference
4193 and then Attribute_Name (Arg) = Name_Identity
4200 -- If statement, need to look inside if there is an else and check
4201 -- each constituent statement sequence for proper termination.
4203 elsif Kind = N_If_Statement
4204 and then Present (Else_Statements (Last_Stm))
4206 Check_Statement_Sequence (Then_Statements (Last_Stm));
4207 Check_Statement_Sequence (Else_Statements (Last_Stm));
4209 if Present (Elsif_Parts (Last_Stm)) then
4211 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
4214 while Present (Elsif_Part) loop
4215 Check_Statement_Sequence (Then_Statements (Elsif_Part));
4223 -- Case statement, check each case for proper termination
4225 elsif Kind = N_Case_Statement then
4229 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
4230 while Present (Case_Alt) loop
4231 Check_Statement_Sequence (Statements (Case_Alt));
4232 Next_Non_Pragma (Case_Alt);
4238 -- Block statement, check its handled sequence of statements
4240 elsif Kind = N_Block_Statement then
4246 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
4255 -- Loop statement. If there is an iteration scheme, we can definitely
4256 -- fall out of the loop. Similarly if there is an exit statement, we
4257 -- can fall out. In either case we need a following return.
4259 elsif Kind = N_Loop_Statement then
4260 if Present (Iteration_Scheme (Last_Stm))
4261 or else Has_Exit (Entity (Identifier (Last_Stm)))
4265 -- A loop with no exit statement or iteration scheme is either
4266 -- an infinite loop, or it has some other exit (raise/return).
4267 -- In either case, no warning is required.
4273 -- Timed entry call, check entry call and delay alternatives
4275 -- Note: in expanded code, the timed entry call has been converted
4276 -- to a set of expanded statements on which the check will work
4277 -- correctly in any case.
4279 elsif Kind = N_Timed_Entry_Call then
4281 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4282 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
4285 -- If statement sequence of entry call alternative is missing,
4286 -- then we can definitely fall through, and we post the error
4287 -- message on the entry call alternative itself.
4289 if No (Statements (ECA)) then
4292 -- If statement sequence of delay alternative is missing, then
4293 -- we can definitely fall through, and we post the error
4294 -- message on the delay alternative itself.
4296 -- Note: if both ECA and DCA are missing the return, then we
4297 -- post only one message, should be enough to fix the bugs.
4298 -- If not we will get a message next time on the DCA when the
4301 elsif No (Statements (DCA)) then
4304 -- Else check both statement sequences
4307 Check_Statement_Sequence (Statements (ECA));
4308 Check_Statement_Sequence (Statements (DCA));
4313 -- Conditional entry call, check entry call and else part
4315 -- Note: in expanded code, the conditional entry call has been
4316 -- converted to a set of expanded statements on which the check
4317 -- will work correctly in any case.
4319 elsif Kind = N_Conditional_Entry_Call then
4321 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4324 -- If statement sequence of entry call alternative is missing,
4325 -- then we can definitely fall through, and we post the error
4326 -- message on the entry call alternative itself.
4328 if No (Statements (ECA)) then
4331 -- Else check statement sequence and else part
4334 Check_Statement_Sequence (Statements (ECA));
4335 Check_Statement_Sequence (Else_Statements (Last_Stm));
4341 -- If we fall through, issue appropriate message
4344 if not Raise_Exception_Call then
4346 ("?RETURN statement missing following this statement!",
4349 ("\?Program_Error may be raised at run time!",
4353 -- Note: we set Err even though we have not issued a warning
4354 -- because we still have a case of a missing return. This is
4355 -- an extremely marginal case, probably will never be noticed
4356 -- but we might as well get it right.
4360 -- Otherwise we have the case of a procedure marked No_Return
4363 if not Raise_Exception_Call then
4365 ("?implied return after this statement " &
4366 "will raise Program_Error",
4369 ("\?procedure & is marked as No_Return!",
4374 RE : constant Node_Id :=
4375 Make_Raise_Program_Error (Sloc (Last_Stm),
4376 Reason => PE_Implicit_Return);
4378 Insert_After (Last_Stm, RE);
4382 end Check_Statement_Sequence;
4384 -- Start of processing for Check_Returns
4388 Check_Statement_Sequence (Statements (HSS));
4390 if Present (Exception_Handlers (HSS)) then
4391 Handler := First_Non_Pragma (Exception_Handlers (HSS));
4392 while Present (Handler) loop
4393 Check_Statement_Sequence (Statements (Handler));
4394 Next_Non_Pragma (Handler);
4399 ----------------------------
4400 -- Check_Subprogram_Order --
4401 ----------------------------
4403 procedure Check_Subprogram_Order (N : Node_Id) is
4405 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
4406 -- This is used to check if S1 > S2 in the sense required by this
4407 -- test, for example nameab < namec, but name2 < name10.
4409 -----------------------------
4410 -- Subprogram_Name_Greater --
4411 -----------------------------
4413 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
4418 -- Remove trailing numeric parts
4421 while S1 (L1) in '0' .. '9' loop
4426 while S2 (L2) in '0' .. '9' loop
4430 -- If non-numeric parts non-equal, that's decisive
4432 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
4435 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
4438 -- If non-numeric parts equal, compare suffixed numeric parts. Note
4439 -- that a missing suffix is treated as numeric zero in this test.
4443 while L1 < S1'Last loop
4445 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
4449 while L2 < S2'Last loop
4451 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
4456 end Subprogram_Name_Greater;
4458 -- Start of processing for Check_Subprogram_Order
4461 -- Check body in alpha order if this is option
4464 and then Style_Check_Order_Subprograms
4465 and then Nkind (N) = N_Subprogram_Body
4466 and then Comes_From_Source (N)
4467 and then In_Extended_Main_Source_Unit (N)
4471 renames Scope_Stack.Table
4472 (Scope_Stack.Last).Last_Subprogram_Name;
4474 Body_Id : constant Entity_Id :=
4475 Defining_Entity (Specification (N));
4478 Get_Decoded_Name_String (Chars (Body_Id));
4481 if Subprogram_Name_Greater
4482 (LSN.all, Name_Buffer (1 .. Name_Len))
4484 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
4490 LSN := new String'(Name_Buffer (1 .. Name_Len));
4493 end Check_Subprogram_Order;
4495 ------------------------------
4496 -- Check_Subtype_Conformant --
4497 ------------------------------
4499 procedure Check_Subtype_Conformant
4500 (New_Id : Entity_Id;
4502 Err_Loc : Node_Id := Empty)
4505 pragma Warnings (Off, Result);
4508 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc);
4509 end Check_Subtype_Conformant;
4511 ---------------------------
4512 -- Check_Type_Conformant --
4513 ---------------------------
4515 procedure Check_Type_Conformant
4516 (New_Id : Entity_Id;
4518 Err_Loc : Node_Id := Empty)
4521 pragma Warnings (Off, Result);
4524 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
4525 end Check_Type_Conformant;
4527 ----------------------
4528 -- Conforming_Types --
4529 ----------------------
4531 function Conforming_Types
4534 Ctype : Conformance_Type;
4535 Get_Inst : Boolean := False) return Boolean
4537 Type_1 : Entity_Id := T1;
4538 Type_2 : Entity_Id := T2;
4539 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
4541 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
4542 -- If neither T1 nor T2 are generic actual types, or if they are in
4543 -- different scopes (e.g. parent and child instances), then verify that
4544 -- the base types are equal. Otherwise T1 and T2 must be on the same
4545 -- subtype chain. The whole purpose of this procedure is to prevent
4546 -- spurious ambiguities in an instantiation that may arise if two
4547 -- distinct generic types are instantiated with the same actual.
4549 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
4550 -- An access parameter can designate an incomplete type. If the
4551 -- incomplete type is the limited view of a type from a limited_
4552 -- with_clause, check whether the non-limited view is available. If
4553 -- it is a (non-limited) incomplete type, get the full view.
4555 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
4556 -- Returns True if and only if either T1 denotes a limited view of T2
4557 -- or T2 denotes a limited view of T1. This can arise when the limited
4558 -- with view of a type is used in a subprogram declaration and the
4559 -- subprogram body is in the scope of a regular with clause for the
4560 -- same unit. In such a case, the two type entities can be considered
4561 -- identical for purposes of conformance checking.
4563 ----------------------
4564 -- Base_Types_Match --
4565 ----------------------
4567 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
4572 elsif Base_Type (T1) = Base_Type (T2) then
4574 -- The following is too permissive. A more precise test should
4575 -- check that the generic actual is an ancestor subtype of the
4578 return not Is_Generic_Actual_Type (T1)
4579 or else not Is_Generic_Actual_Type (T2)
4580 or else Scope (T1) /= Scope (T2);
4585 end Base_Types_Match;
4587 --------------------------
4588 -- Find_Designated_Type --
4589 --------------------------
4591 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
4595 Desig := Directly_Designated_Type (T);
4597 if Ekind (Desig) = E_Incomplete_Type then
4599 -- If regular incomplete type, get full view if available
4601 if Present (Full_View (Desig)) then
4602 Desig := Full_View (Desig);
4604 -- If limited view of a type, get non-limited view if available,
4605 -- and check again for a regular incomplete type.
4607 elsif Present (Non_Limited_View (Desig)) then
4608 Desig := Get_Full_View (Non_Limited_View (Desig));
4613 end Find_Designated_Type;
4615 -------------------------------
4616 -- Matches_Limited_With_View --
4617 -------------------------------
4619 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
4621 -- In some cases a type imported through a limited_with clause, and
4622 -- its nonlimited view are both visible, for example in an anonymous
4623 -- access-to-class-wide type in a formal. Both entities designate the
4626 if From_With_Type (T1)
4627 and then T2 = Available_View (T1)
4631 elsif From_With_Type (T2)
4632 and then T1 = Available_View (T2)
4639 end Matches_Limited_With_View;
4641 -- Start of processing for Conforming_Types
4644 -- The context is an instance association for a formal
4645 -- access-to-subprogram type; the formal parameter types require
4646 -- mapping because they may denote other formal parameters of the
4650 Type_1 := Get_Instance_Of (T1);
4651 Type_2 := Get_Instance_Of (T2);
4654 -- If one of the types is a view of the other introduced by a limited
4655 -- with clause, treat these as conforming for all purposes.
4657 if Matches_Limited_With_View (T1, T2) then
4660 elsif Base_Types_Match (Type_1, Type_2) then
4661 return Ctype <= Mode_Conformant
4662 or else Subtypes_Statically_Match (Type_1, Type_2);
4664 elsif Is_Incomplete_Or_Private_Type (Type_1)
4665 and then Present (Full_View (Type_1))
4666 and then Base_Types_Match (Full_View (Type_1), Type_2)
4668 return Ctype <= Mode_Conformant
4669 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
4671 elsif Ekind (Type_2) = E_Incomplete_Type
4672 and then Present (Full_View (Type_2))
4673 and then Base_Types_Match (Type_1, Full_View (Type_2))
4675 return Ctype <= Mode_Conformant
4676 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4678 elsif Is_Private_Type (Type_2)
4679 and then In_Instance
4680 and then Present (Full_View (Type_2))
4681 and then Base_Types_Match (Type_1, Full_View (Type_2))
4683 return Ctype <= Mode_Conformant
4684 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4687 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
4688 -- treated recursively because they carry a signature.
4690 Are_Anonymous_Access_To_Subprogram_Types :=
4691 Ekind (Type_1) = Ekind (Type_2)
4693 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
4695 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
4697 -- Test anonymous access type case. For this case, static subtype
4698 -- matching is required for mode conformance (RM 6.3.1(15)). We check
4699 -- the base types because we may have built internal subtype entities
4700 -- to handle null-excluding types (see Process_Formals).
4702 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
4704 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
4705 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
4708 Desig_1 : Entity_Id;
4709 Desig_2 : Entity_Id;
4712 -- In Ada2005, access constant indicators must match for
4713 -- subtype conformance.
4715 if Ada_Version >= Ada_05
4716 and then Ctype >= Subtype_Conformant
4718 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
4723 Desig_1 := Find_Designated_Type (Type_1);
4725 Desig_2 := Find_Designated_Type (Type_2);
4727 -- If the context is an instance association for a formal
4728 -- access-to-subprogram type; formal access parameter designated
4729 -- types require mapping because they may denote other formal
4730 -- parameters of the generic unit.
4733 Desig_1 := Get_Instance_Of (Desig_1);
4734 Desig_2 := Get_Instance_Of (Desig_2);
4737 -- It is possible for a Class_Wide_Type to be introduced for an
4738 -- incomplete type, in which case there is a separate class_ wide
4739 -- type for the full view. The types conform if their Etypes
4740 -- conform, i.e. one may be the full view of the other. This can
4741 -- only happen in the context of an access parameter, other uses
4742 -- of an incomplete Class_Wide_Type are illegal.
4744 if Is_Class_Wide_Type (Desig_1)
4745 and then Is_Class_Wide_Type (Desig_2)
4749 (Etype (Base_Type (Desig_1)),
4750 Etype (Base_Type (Desig_2)), Ctype);
4752 elsif Are_Anonymous_Access_To_Subprogram_Types then
4753 if Ada_Version < Ada_05 then
4754 return Ctype = Type_Conformant
4756 Subtypes_Statically_Match (Desig_1, Desig_2);
4758 -- We must check the conformance of the signatures themselves
4762 Conformant : Boolean;
4765 (Desig_1, Desig_2, Ctype, False, Conformant);
4771 return Base_Type (Desig_1) = Base_Type (Desig_2)
4772 and then (Ctype = Type_Conformant
4774 Subtypes_Statically_Match (Desig_1, Desig_2));
4778 -- Otherwise definitely no match
4781 if ((Ekind (Type_1) = E_Anonymous_Access_Type
4782 and then Is_Access_Type (Type_2))
4783 or else (Ekind (Type_2) = E_Anonymous_Access_Type
4784 and then Is_Access_Type (Type_1)))
4787 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
4789 May_Hide_Profile := True;
4794 end Conforming_Types;
4796 --------------------------
4797 -- Create_Extra_Formals --
4798 --------------------------
4800 procedure Create_Extra_Formals (E : Entity_Id) is
4802 First_Extra : Entity_Id := Empty;
4803 Last_Extra : Entity_Id;
4804 Formal_Type : Entity_Id;
4805 P_Formal : Entity_Id := Empty;
4807 function Add_Extra_Formal
4808 (Assoc_Entity : Entity_Id;
4811 Suffix : String) return Entity_Id;
4812 -- Add an extra formal to the current list of formals and extra formals.
4813 -- The extra formal is added to the end of the list of extra formals,
4814 -- and also returned as the result. These formals are always of mode IN.
4815 -- The new formal has the type Typ, is declared in Scope, and its name
4816 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
4818 ----------------------
4819 -- Add_Extra_Formal --
4820 ----------------------
4822 function Add_Extra_Formal
4823 (Assoc_Entity : Entity_Id;
4826 Suffix : String) return Entity_Id
4828 EF : constant Entity_Id :=
4829 Make_Defining_Identifier (Sloc (Assoc_Entity),
4830 Chars => New_External_Name (Chars (Assoc_Entity),
4834 -- A little optimization. Never generate an extra formal for the
4835 -- _init operand of an initialization procedure, since it could
4838 if Chars (Formal) = Name_uInit then
4842 Set_Ekind (EF, E_In_Parameter);
4843 Set_Actual_Subtype (EF, Typ);
4844 Set_Etype (EF, Typ);
4845 Set_Scope (EF, Scope);
4846 Set_Mechanism (EF, Default_Mechanism);
4847 Set_Formal_Validity (EF);
4849 if No (First_Extra) then
4851 Set_Extra_Formals (Scope, First_Extra);
4854 if Present (Last_Extra) then
4855 Set_Extra_Formal (Last_Extra, EF);
4861 end Add_Extra_Formal;
4863 -- Start of processing for Create_Extra_Formals
4866 -- We never generate extra formals if expansion is not active
4867 -- because we don't need them unless we are generating code.
4869 if not Expander_Active then
4873 -- If this is a derived subprogram then the subtypes of the parent
4874 -- subprogram's formal parameters will be used to to determine the need
4875 -- for extra formals.
4877 if Is_Overloadable (E) and then Present (Alias (E)) then
4878 P_Formal := First_Formal (Alias (E));
4881 Last_Extra := Empty;
4882 Formal := First_Formal (E);
4883 while Present (Formal) loop
4884 Last_Extra := Formal;
4885 Next_Formal (Formal);
4888 -- If Extra_formals were already created, don't do it again. This
4889 -- situation may arise for subprogram types created as part of
4890 -- dispatching calls (see Expand_Dispatching_Call)
4892 if Present (Last_Extra) and then
4893 Present (Extra_Formal (Last_Extra))
4898 -- If the subprogram is a predefined dispatching subprogram then don't
4899 -- generate any extra constrained or accessibility level formals. In
4900 -- general we suppress these for internal subprograms (by not calling
4901 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
4902 -- generated stream attributes do get passed through because extra
4903 -- build-in-place formals are needed in some cases (limited 'Input).
4905 if Is_Predefined_Dispatching_Operation (E) then
4906 goto Test_For_BIP_Extras;
4909 Formal := First_Formal (E);
4910 while Present (Formal) loop
4912 -- Create extra formal for supporting the attribute 'Constrained.
4913 -- The case of a private type view without discriminants also
4914 -- requires the extra formal if the underlying type has defaulted
4917 if Ekind (Formal) /= E_In_Parameter then
4918 if Present (P_Formal) then
4919 Formal_Type := Etype (P_Formal);
4921 Formal_Type := Etype (Formal);
4924 -- Do not produce extra formals for Unchecked_Union parameters.
4925 -- Jump directly to the end of the loop.
4927 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
4928 goto Skip_Extra_Formal_Generation;
4931 if not Has_Discriminants (Formal_Type)
4932 and then Ekind (Formal_Type) in Private_Kind
4933 and then Present (Underlying_Type (Formal_Type))
4935 Formal_Type := Underlying_Type (Formal_Type);
4938 if Has_Discriminants (Formal_Type)
4939 and then not Is_Constrained (Formal_Type)
4940 and then not Is_Indefinite_Subtype (Formal_Type)
4942 Set_Extra_Constrained
4943 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "F"));
4947 -- Create extra formal for supporting accessibility checking. This
4948 -- is done for both anonymous access formals and formals of named
4949 -- access types that are marked as controlling formals. The latter
4950 -- case can occur when Expand_Dispatching_Call creates a subprogram
4951 -- type and substitutes the types of access-to-class-wide actuals
4952 -- for the anonymous access-to-specific-type of controlling formals.
4953 -- Base_Type is applied because in cases where there is a null
4954 -- exclusion the formal may have an access subtype.
4956 -- This is suppressed if we specifically suppress accessibility
4957 -- checks at the package level for either the subprogram, or the
4958 -- package in which it resides. However, we do not suppress it
4959 -- simply if the scope has accessibility checks suppressed, since
4960 -- this could cause trouble when clients are compiled with a
4961 -- different suppression setting. The explicit checks at the
4962 -- package level are safe from this point of view.
4964 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
4965 or else (Is_Controlling_Formal (Formal)
4966 and then Is_Access_Type (Base_Type (Etype (Formal)))))
4968 (Explicit_Suppress (E, Accessibility_Check)
4970 Explicit_Suppress (Scope (E), Accessibility_Check))
4973 or else Present (Extra_Accessibility (P_Formal)))
4975 -- Temporary kludge: for now we avoid creating the extra formal
4976 -- for access parameters of protected operations because of
4977 -- problem with the case of internal protected calls. ???
4979 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
4980 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
4982 Set_Extra_Accessibility
4983 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "F"));
4987 -- This label is required when skipping extra formal generation for
4988 -- Unchecked_Union parameters.
4990 <<Skip_Extra_Formal_Generation>>
4992 if Present (P_Formal) then
4993 Next_Formal (P_Formal);
4996 Next_Formal (Formal);
4999 <<Test_For_BIP_Extras>>
5001 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
5002 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
5004 if Ada_Version >= Ada_05 and then Is_Build_In_Place_Function (E) then
5006 Result_Subt : constant Entity_Id := Etype (E);
5008 Discard : Entity_Id;
5009 pragma Warnings (Off, Discard);
5012 -- In the case of functions with unconstrained result subtypes,
5013 -- add a 3-state formal indicating whether the return object is
5014 -- allocated by the caller (0), or should be allocated by the
5015 -- callee on the secondary stack (1) or in the global heap (2).
5016 -- For the moment we just use Natural for the type of this formal.
5017 -- Note that this formal isn't usually needed in the case where
5018 -- the result subtype is constrained, but it is needed when the
5019 -- function has a tagged result, because generally such functions
5020 -- can be called in a dispatching context and such calls must be
5021 -- handled like calls to a class-wide function.
5023 if not Is_Constrained (Result_Subt)
5024 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
5028 (E, Standard_Natural,
5029 E, BIP_Formal_Suffix (BIP_Alloc_Form));
5032 -- In the case of functions whose result type has controlled
5033 -- parts, we have an extra formal of type
5034 -- System.Finalization_Implementation.Finalizable_Ptr_Ptr. That
5035 -- is, we are passing a pointer to a finalization list (which is
5036 -- itself a pointer). This extra formal is then passed along to
5037 -- Move_Final_List in case of successful completion of a return
5038 -- statement. We cannot pass an 'in out' parameter, because we
5039 -- need to update the finalization list during an abort-deferred
5040 -- region, rather than using copy-back after the function
5041 -- returns. This is true even if we are able to get away with
5042 -- having 'in out' parameters, which are normally illegal for
5043 -- functions. This formal is also needed when the function has
5044 -- a tagged result, because generally such functions can be called
5045 -- in a dispatching context and such calls must be handled like
5046 -- calls to class-wide functions.
5048 if Controlled_Type (Result_Subt)
5049 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
5053 (E, RTE (RE_Finalizable_Ptr_Ptr),
5054 E, BIP_Formal_Suffix (BIP_Final_List));
5057 -- If the result type contains tasks, we have two extra formals:
5058 -- the master of the tasks to be created, and the caller's
5059 -- activation chain.
5061 if Has_Task (Result_Subt) then
5064 (E, RTE (RE_Master_Id),
5065 E, BIP_Formal_Suffix (BIP_Master));
5068 (E, RTE (RE_Activation_Chain_Access),
5069 E, BIP_Formal_Suffix (BIP_Activation_Chain));
5072 -- All build-in-place functions get an extra formal that will be
5073 -- passed the address of the return object within the caller.
5076 Formal_Type : constant Entity_Id :=
5078 (E_Anonymous_Access_Type, E,
5079 Scope_Id => Scope (E));
5081 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
5082 Set_Etype (Formal_Type, Formal_Type);
5083 Set_Depends_On_Private
5084 (Formal_Type, Has_Private_Component (Formal_Type));
5085 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
5086 Set_Is_Access_Constant (Formal_Type, False);
5088 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
5089 -- the designated type comes from the limited view (for
5090 -- back-end purposes).
5092 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
5094 Layout_Type (Formal_Type);
5098 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
5102 end Create_Extra_Formals;
5104 -----------------------------
5105 -- Enter_Overloaded_Entity --
5106 -----------------------------
5108 procedure Enter_Overloaded_Entity (S : Entity_Id) is
5109 E : Entity_Id := Current_Entity_In_Scope (S);
5110 C_E : Entity_Id := Current_Entity (S);
5114 Set_Has_Homonym (E);
5115 Set_Has_Homonym (S);
5118 Set_Is_Immediately_Visible (S);
5119 Set_Scope (S, Current_Scope);
5121 -- Chain new entity if front of homonym in current scope, so that
5122 -- homonyms are contiguous.
5127 while Homonym (C_E) /= E loop
5128 C_E := Homonym (C_E);
5131 Set_Homonym (C_E, S);
5135 Set_Current_Entity (S);
5140 Append_Entity (S, Current_Scope);
5141 Set_Public_Status (S);
5143 if Debug_Flag_E then
5144 Write_Str ("New overloaded entity chain: ");
5145 Write_Name (Chars (S));
5148 while Present (E) loop
5149 Write_Str (" "); Write_Int (Int (E));
5156 -- Generate warning for hiding
5159 and then Comes_From_Source (S)
5160 and then In_Extended_Main_Source_Unit (S)
5167 -- Warn unless genuine overloading
5169 if (not Is_Overloadable (E) or else Subtype_Conformant (E, S))
5170 and then (Is_Immediately_Visible (E)
5172 Is_Potentially_Use_Visible (S))
5174 Error_Msg_Sloc := Sloc (E);
5175 Error_Msg_N ("declaration of & hides one#?", S);
5179 end Enter_Overloaded_Entity;
5181 -----------------------------
5182 -- Find_Corresponding_Spec --
5183 -----------------------------
5185 function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is
5186 Spec : constant Node_Id := Specification (N);
5187 Designator : constant Entity_Id := Defining_Entity (Spec);
5192 E := Current_Entity (Designator);
5193 while Present (E) loop
5195 -- We are looking for a matching spec. It must have the same scope,
5196 -- and the same name, and either be type conformant, or be the case
5197 -- of a library procedure spec and its body (which belong to one
5198 -- another regardless of whether they are type conformant or not).
5200 if Scope (E) = Current_Scope then
5201 if Current_Scope = Standard_Standard
5202 or else (Ekind (E) = Ekind (Designator)
5203 and then Type_Conformant (E, Designator))
5205 -- Within an instantiation, we know that spec and body are
5206 -- subtype conformant, because they were subtype conformant
5207 -- in the generic. We choose the subtype-conformant entity
5208 -- here as well, to resolve spurious ambiguities in the
5209 -- instance that were not present in the generic (i.e. when
5210 -- two different types are given the same actual). If we are
5211 -- looking for a spec to match a body, full conformance is
5215 Set_Convention (Designator, Convention (E));
5217 if Nkind (N) = N_Subprogram_Body
5218 and then Present (Homonym (E))
5219 and then not Fully_Conformant (E, Designator)
5223 elsif not Subtype_Conformant (E, Designator) then
5228 if not Has_Completion (E) then
5230 if Nkind (N) /= N_Subprogram_Body_Stub then
5231 Set_Corresponding_Spec (N, E);
5234 Set_Has_Completion (E);
5237 elsif Nkind (Parent (N)) = N_Subunit then
5239 -- If this is the proper body of a subunit, the completion
5240 -- flag is set when analyzing the stub.
5244 -- If E is an internal function with a controlling result
5245 -- that was created for an operation inherited by a null
5246 -- extension, it may be overridden by a body without a previous
5247 -- spec (one more reason why these should be shunned). In that
5248 -- case remove the generated body, because the current one is
5249 -- the explicit overriding.
5251 elsif Ekind (E) = E_Function
5252 and then Ada_Version >= Ada_05
5253 and then not Comes_From_Source (E)
5254 and then Has_Controlling_Result (E)
5255 and then Is_Null_Extension (Etype (E))
5256 and then Comes_From_Source (Spec)
5258 Set_Has_Completion (E, False);
5260 if Expander_Active then
5262 (Unit_Declaration_Node
5263 (Corresponding_Body (Unit_Declaration_Node (E))));
5266 -- If expansion is disabled, the wrapper function has not
5267 -- been generated, and this is the standard case of a late
5268 -- body overriding an inherited operation.
5274 -- If body already exists, this is an error unless the
5275 -- previous declaration is the implicit declaration of
5276 -- a derived subprogram, or this is a spurious overloading
5279 elsif No (Alias (E))
5280 and then not Is_Intrinsic_Subprogram (E)
5281 and then not In_Instance
5283 Error_Msg_Sloc := Sloc (E);
5284 if Is_Imported (E) then
5286 ("body not allowed for imported subprogram & declared#",
5289 Error_Msg_NE ("duplicate body for & declared#", N, E);
5293 elsif Is_Child_Unit (E)
5295 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
5297 Nkind (Parent (Unit_Declaration_Node (Designator))) =
5300 -- Child units cannot be overloaded, so a conformance mismatch
5301 -- between body and a previous spec is an error.
5304 ("body of child unit does not match previous declaration", N);
5312 -- On exit, we know that no previous declaration of subprogram exists
5315 end Find_Corresponding_Spec;
5317 ----------------------
5318 -- Fully_Conformant --
5319 ----------------------
5321 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5324 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
5326 end Fully_Conformant;
5328 ----------------------------------
5329 -- Fully_Conformant_Expressions --
5330 ----------------------------------
5332 function Fully_Conformant_Expressions
5333 (Given_E1 : Node_Id;
5334 Given_E2 : Node_Id) return Boolean
5336 E1 : constant Node_Id := Original_Node (Given_E1);
5337 E2 : constant Node_Id := Original_Node (Given_E2);
5338 -- We always test conformance on original nodes, since it is possible
5339 -- for analysis and/or expansion to make things look as though they
5340 -- conform when they do not, e.g. by converting 1+2 into 3.
5342 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
5343 renames Fully_Conformant_Expressions;
5345 function FCL (L1, L2 : List_Id) return Boolean;
5346 -- Compare elements of two lists for conformance. Elements have to
5347 -- be conformant, and actuals inserted as default parameters do not
5348 -- match explicit actuals with the same value.
5350 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
5351 -- Compare an operator node with a function call
5357 function FCL (L1, L2 : List_Id) return Boolean is
5361 if L1 = No_List then
5367 if L2 = No_List then
5373 -- Compare two lists, skipping rewrite insertions (we want to
5374 -- compare the original trees, not the expanded versions!)
5377 if Is_Rewrite_Insertion (N1) then
5379 elsif Is_Rewrite_Insertion (N2) then
5385 elsif not FCE (N1, N2) then
5398 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
5399 Actuals : constant List_Id := Parameter_Associations (Call_Node);
5404 or else Entity (Op_Node) /= Entity (Name (Call_Node))
5409 Act := First (Actuals);
5411 if Nkind (Op_Node) in N_Binary_Op then
5413 if not FCE (Left_Opnd (Op_Node), Act) then
5420 return Present (Act)
5421 and then FCE (Right_Opnd (Op_Node), Act)
5422 and then No (Next (Act));
5426 -- Start of processing for Fully_Conformant_Expressions
5429 -- Non-conformant if paren count does not match. Note: if some idiot
5430 -- complains that we don't do this right for more than 3 levels of
5431 -- parentheses, they will be treated with the respect they deserve!
5433 if Paren_Count (E1) /= Paren_Count (E2) then
5436 -- If same entities are referenced, then they are conformant even if
5437 -- they have different forms (RM 8.3.1(19-20)).
5439 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
5440 if Present (Entity (E1)) then
5441 return Entity (E1) = Entity (E2)
5442 or else (Chars (Entity (E1)) = Chars (Entity (E2))
5443 and then Ekind (Entity (E1)) = E_Discriminant
5444 and then Ekind (Entity (E2)) = E_In_Parameter);
5446 elsif Nkind (E1) = N_Expanded_Name
5447 and then Nkind (E2) = N_Expanded_Name
5448 and then Nkind (Selector_Name (E1)) = N_Character_Literal
5449 and then Nkind (Selector_Name (E2)) = N_Character_Literal
5451 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
5454 -- Identifiers in component associations don't always have
5455 -- entities, but their names must conform.
5457 return Nkind (E1) = N_Identifier
5458 and then Nkind (E2) = N_Identifier
5459 and then Chars (E1) = Chars (E2);
5462 elsif Nkind (E1) = N_Character_Literal
5463 and then Nkind (E2) = N_Expanded_Name
5465 return Nkind (Selector_Name (E2)) = N_Character_Literal
5466 and then Chars (E1) = Chars (Selector_Name (E2));
5468 elsif Nkind (E2) = N_Character_Literal
5469 and then Nkind (E1) = N_Expanded_Name
5471 return Nkind (Selector_Name (E1)) = N_Character_Literal
5472 and then Chars (E2) = Chars (Selector_Name (E1));
5474 elsif Nkind (E1) in N_Op
5475 and then Nkind (E2) = N_Function_Call
5477 return FCO (E1, E2);
5479 elsif Nkind (E2) in N_Op
5480 and then Nkind (E1) = N_Function_Call
5482 return FCO (E2, E1);
5484 -- Otherwise we must have the same syntactic entity
5486 elsif Nkind (E1) /= Nkind (E2) then
5489 -- At this point, we specialize by node type
5496 FCL (Expressions (E1), Expressions (E2))
5497 and then FCL (Component_Associations (E1),
5498 Component_Associations (E2));
5501 if Nkind (Expression (E1)) = N_Qualified_Expression
5503 Nkind (Expression (E2)) = N_Qualified_Expression
5505 return FCE (Expression (E1), Expression (E2));
5507 -- Check that the subtype marks and any constraints
5512 Indic1 : constant Node_Id := Expression (E1);
5513 Indic2 : constant Node_Id := Expression (E2);
5518 if Nkind (Indic1) /= N_Subtype_Indication then
5520 Nkind (Indic2) /= N_Subtype_Indication
5521 and then Entity (Indic1) = Entity (Indic2);
5523 elsif Nkind (Indic2) /= N_Subtype_Indication then
5525 Nkind (Indic1) /= N_Subtype_Indication
5526 and then Entity (Indic1) = Entity (Indic2);
5529 if Entity (Subtype_Mark (Indic1)) /=
5530 Entity (Subtype_Mark (Indic2))
5535 Elt1 := First (Constraints (Constraint (Indic1)));
5536 Elt2 := First (Constraints (Constraint (Indic2)));
5538 while Present (Elt1) and then Present (Elt2) loop
5539 if not FCE (Elt1, Elt2) then
5552 when N_Attribute_Reference =>
5554 Attribute_Name (E1) = Attribute_Name (E2)
5555 and then FCL (Expressions (E1), Expressions (E2));
5559 Entity (E1) = Entity (E2)
5560 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
5561 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5563 when N_And_Then | N_Or_Else | N_Membership_Test =>
5565 FCE (Left_Opnd (E1), Left_Opnd (E2))
5567 FCE (Right_Opnd (E1), Right_Opnd (E2));
5569 when N_Character_Literal =>
5571 Char_Literal_Value (E1) = Char_Literal_Value (E2);
5573 when N_Component_Association =>
5575 FCL (Choices (E1), Choices (E2))
5576 and then FCE (Expression (E1), Expression (E2));
5578 when N_Conditional_Expression =>
5580 FCL (Expressions (E1), Expressions (E2));
5582 when N_Explicit_Dereference =>
5584 FCE (Prefix (E1), Prefix (E2));
5586 when N_Extension_Aggregate =>
5588 FCL (Expressions (E1), Expressions (E2))
5589 and then Null_Record_Present (E1) =
5590 Null_Record_Present (E2)
5591 and then FCL (Component_Associations (E1),
5592 Component_Associations (E2));
5594 when N_Function_Call =>
5596 FCE (Name (E1), Name (E2))
5597 and then FCL (Parameter_Associations (E1),
5598 Parameter_Associations (E2));
5600 when N_Indexed_Component =>
5602 FCE (Prefix (E1), Prefix (E2))
5603 and then FCL (Expressions (E1), Expressions (E2));
5605 when N_Integer_Literal =>
5606 return (Intval (E1) = Intval (E2));
5611 when N_Operator_Symbol =>
5613 Chars (E1) = Chars (E2);
5615 when N_Others_Choice =>
5618 when N_Parameter_Association =>
5620 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
5621 and then FCE (Explicit_Actual_Parameter (E1),
5622 Explicit_Actual_Parameter (E2));
5624 when N_Qualified_Expression =>
5626 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5627 and then FCE (Expression (E1), Expression (E2));
5631 FCE (Low_Bound (E1), Low_Bound (E2))
5632 and then FCE (High_Bound (E1), High_Bound (E2));
5634 when N_Real_Literal =>
5635 return (Realval (E1) = Realval (E2));
5637 when N_Selected_Component =>
5639 FCE (Prefix (E1), Prefix (E2))
5640 and then FCE (Selector_Name (E1), Selector_Name (E2));
5644 FCE (Prefix (E1), Prefix (E2))
5645 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
5647 when N_String_Literal =>
5649 S1 : constant String_Id := Strval (E1);
5650 S2 : constant String_Id := Strval (E2);
5651 L1 : constant Nat := String_Length (S1);
5652 L2 : constant Nat := String_Length (S2);
5659 for J in 1 .. L1 loop
5660 if Get_String_Char (S1, J) /=
5661 Get_String_Char (S2, J)
5671 when N_Type_Conversion =>
5673 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5674 and then FCE (Expression (E1), Expression (E2));
5678 Entity (E1) = Entity (E2)
5679 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5681 when N_Unchecked_Type_Conversion =>
5683 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5684 and then FCE (Expression (E1), Expression (E2));
5686 -- All other node types cannot appear in this context. Strictly
5687 -- we should raise a fatal internal error. Instead we just ignore
5688 -- the nodes. This means that if anyone makes a mistake in the
5689 -- expander and mucks an expression tree irretrievably, the
5690 -- result will be a failure to detect a (probably very obscure)
5691 -- case of non-conformance, which is better than bombing on some
5692 -- case where two expressions do in fact conform.
5699 end Fully_Conformant_Expressions;
5701 ----------------------------------------
5702 -- Fully_Conformant_Discrete_Subtypes --
5703 ----------------------------------------
5705 function Fully_Conformant_Discrete_Subtypes
5706 (Given_S1 : Node_Id;
5707 Given_S2 : Node_Id) return Boolean
5709 S1 : constant Node_Id := Original_Node (Given_S1);
5710 S2 : constant Node_Id := Original_Node (Given_S2);
5712 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
5713 -- Special-case for a bound given by a discriminant, which in the body
5714 -- is replaced with the discriminal of the enclosing type.
5716 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
5717 -- Check both bounds
5719 -----------------------
5720 -- Conforming_Bounds --
5721 -----------------------
5723 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
5725 if Is_Entity_Name (B1)
5726 and then Is_Entity_Name (B2)
5727 and then Ekind (Entity (B1)) = E_Discriminant
5729 return Chars (B1) = Chars (B2);
5732 return Fully_Conformant_Expressions (B1, B2);
5734 end Conforming_Bounds;
5736 -----------------------
5737 -- Conforming_Ranges --
5738 -----------------------
5740 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
5743 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
5745 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
5746 end Conforming_Ranges;
5748 -- Start of processing for Fully_Conformant_Discrete_Subtypes
5751 if Nkind (S1) /= Nkind (S2) then
5754 elsif Is_Entity_Name (S1) then
5755 return Entity (S1) = Entity (S2);
5757 elsif Nkind (S1) = N_Range then
5758 return Conforming_Ranges (S1, S2);
5760 elsif Nkind (S1) = N_Subtype_Indication then
5762 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
5765 (Range_Expression (Constraint (S1)),
5766 Range_Expression (Constraint (S2)));
5770 end Fully_Conformant_Discrete_Subtypes;
5772 --------------------
5773 -- Install_Entity --
5774 --------------------
5776 procedure Install_Entity (E : Entity_Id) is
5777 Prev : constant Entity_Id := Current_Entity (E);
5779 Set_Is_Immediately_Visible (E);
5780 Set_Current_Entity (E);
5781 Set_Homonym (E, Prev);
5784 ---------------------
5785 -- Install_Formals --
5786 ---------------------
5788 procedure Install_Formals (Id : Entity_Id) is
5791 F := First_Formal (Id);
5792 while Present (F) loop
5796 end Install_Formals;
5798 ---------------------------------
5799 -- Is_Non_Overriding_Operation --
5800 ---------------------------------
5802 function Is_Non_Overriding_Operation
5803 (Prev_E : Entity_Id;
5804 New_E : Entity_Id) return Boolean
5808 G_Typ : Entity_Id := Empty;
5810 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
5811 -- If F_Type is a derived type associated with a generic actual subtype,
5812 -- then return its Generic_Parent_Type attribute, else return Empty.
5814 function Types_Correspond
5815 (P_Type : Entity_Id;
5816 N_Type : Entity_Id) return Boolean;
5817 -- Returns true if and only if the types (or designated types in the
5818 -- case of anonymous access types) are the same or N_Type is derived
5819 -- directly or indirectly from P_Type.
5821 -----------------------------
5822 -- Get_Generic_Parent_Type --
5823 -----------------------------
5825 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
5830 if Is_Derived_Type (F_Typ)
5831 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
5833 -- The tree must be traversed to determine the parent subtype in
5834 -- the generic unit, which unfortunately isn't always available
5835 -- via semantic attributes. ??? (Note: The use of Original_Node
5836 -- is needed for cases where a full derived type has been
5839 Indic := Subtype_Indication
5840 (Type_Definition (Original_Node (Parent (F_Typ))));
5842 if Nkind (Indic) = N_Subtype_Indication then
5843 G_Typ := Entity (Subtype_Mark (Indic));
5845 G_Typ := Entity (Indic);
5848 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
5849 and then Present (Generic_Parent_Type (Parent (G_Typ)))
5851 return Generic_Parent_Type (Parent (G_Typ));
5856 end Get_Generic_Parent_Type;
5858 ----------------------
5859 -- Types_Correspond --
5860 ----------------------
5862 function Types_Correspond
5863 (P_Type : Entity_Id;
5864 N_Type : Entity_Id) return Boolean
5866 Prev_Type : Entity_Id := Base_Type (P_Type);
5867 New_Type : Entity_Id := Base_Type (N_Type);
5870 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
5871 Prev_Type := Designated_Type (Prev_Type);
5874 if Ekind (New_Type) = E_Anonymous_Access_Type then
5875 New_Type := Designated_Type (New_Type);
5878 if Prev_Type = New_Type then
5881 elsif not Is_Class_Wide_Type (New_Type) then
5882 while Etype (New_Type) /= New_Type loop
5883 New_Type := Etype (New_Type);
5884 if New_Type = Prev_Type then
5890 end Types_Correspond;
5892 -- Start of processing for Is_Non_Overriding_Operation
5895 -- In the case where both operations are implicit derived subprograms
5896 -- then neither overrides the other. This can only occur in certain
5897 -- obscure cases (e.g., derivation from homographs created in a generic
5900 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
5903 elsif Ekind (Current_Scope) = E_Package
5904 and then Is_Generic_Instance (Current_Scope)
5905 and then In_Private_Part (Current_Scope)
5906 and then Comes_From_Source (New_E)
5908 -- We examine the formals and result subtype of the inherited
5909 -- operation, to determine whether their type is derived from (the
5910 -- instance of) a generic type.
5912 Formal := First_Formal (Prev_E);
5914 while Present (Formal) loop
5915 F_Typ := Base_Type (Etype (Formal));
5917 if Ekind (F_Typ) = E_Anonymous_Access_Type then
5918 F_Typ := Designated_Type (F_Typ);
5921 G_Typ := Get_Generic_Parent_Type (F_Typ);
5923 Next_Formal (Formal);
5926 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
5927 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
5934 -- If the generic type is a private type, then the original
5935 -- operation was not overriding in the generic, because there was
5936 -- no primitive operation to override.
5938 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
5939 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
5940 N_Formal_Private_Type_Definition
5944 -- The generic parent type is the ancestor of a formal derived
5945 -- type declaration. We need to check whether it has a primitive
5946 -- operation that should be overridden by New_E in the generic.
5950 P_Formal : Entity_Id;
5951 N_Formal : Entity_Id;
5955 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
5958 while Present (Prim_Elt) loop
5959 P_Prim := Node (Prim_Elt);
5961 if Chars (P_Prim) = Chars (New_E)
5962 and then Ekind (P_Prim) = Ekind (New_E)
5964 P_Formal := First_Formal (P_Prim);
5965 N_Formal := First_Formal (New_E);
5966 while Present (P_Formal) and then Present (N_Formal) loop
5967 P_Typ := Etype (P_Formal);
5968 N_Typ := Etype (N_Formal);
5970 if not Types_Correspond (P_Typ, N_Typ) then
5974 Next_Entity (P_Formal);
5975 Next_Entity (N_Formal);
5978 -- Found a matching primitive operation belonging to the
5979 -- formal ancestor type, so the new subprogram is
5983 and then No (N_Formal)
5984 and then (Ekind (New_E) /= E_Function
5987 (Etype (P_Prim), Etype (New_E)))
5993 Next_Elmt (Prim_Elt);
5996 -- If no match found, then the new subprogram does not
5997 -- override in the generic (nor in the instance).
6005 end Is_Non_Overriding_Operation;
6007 ------------------------------
6008 -- Make_Inequality_Operator --
6009 ------------------------------
6011 -- S is the defining identifier of an equality operator. We build a
6012 -- subprogram declaration with the right signature. This operation is
6013 -- intrinsic, because it is always expanded as the negation of the
6014 -- call to the equality function.
6016 procedure Make_Inequality_Operator (S : Entity_Id) is
6017 Loc : constant Source_Ptr := Sloc (S);
6020 Op_Name : Entity_Id;
6022 FF : constant Entity_Id := First_Formal (S);
6023 NF : constant Entity_Id := Next_Formal (FF);
6026 -- Check that equality was properly defined, ignore call if not
6033 A : constant Entity_Id :=
6034 Make_Defining_Identifier (Sloc (FF),
6035 Chars => Chars (FF));
6037 B : constant Entity_Id :=
6038 Make_Defining_Identifier (Sloc (NF),
6039 Chars => Chars (NF));
6042 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
6044 Formals := New_List (
6045 Make_Parameter_Specification (Loc,
6046 Defining_Identifier => A,
6048 New_Reference_To (Etype (First_Formal (S)),
6049 Sloc (Etype (First_Formal (S))))),
6051 Make_Parameter_Specification (Loc,
6052 Defining_Identifier => B,
6054 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
6055 Sloc (Etype (Next_Formal (First_Formal (S)))))));
6058 Make_Subprogram_Declaration (Loc,
6060 Make_Function_Specification (Loc,
6061 Defining_Unit_Name => Op_Name,
6062 Parameter_Specifications => Formals,
6063 Result_Definition =>
6064 New_Reference_To (Standard_Boolean, Loc)));
6066 -- Insert inequality right after equality if it is explicit or after
6067 -- the derived type when implicit. These entities are created only
6068 -- for visibility purposes, and eventually replaced in the course of
6069 -- expansion, so they do not need to be attached to the tree and seen
6070 -- by the back-end. Keeping them internal also avoids spurious
6071 -- freezing problems. The declaration is inserted in the tree for
6072 -- analysis, and removed afterwards. If the equality operator comes
6073 -- from an explicit declaration, attach the inequality immediately
6074 -- after. Else the equality is inherited from a derived type
6075 -- declaration, so insert inequality after that declaration.
6077 if No (Alias (S)) then
6078 Insert_After (Unit_Declaration_Node (S), Decl);
6079 elsif Is_List_Member (Parent (S)) then
6080 Insert_After (Parent (S), Decl);
6082 Insert_After (Parent (Etype (First_Formal (S))), Decl);
6085 Mark_Rewrite_Insertion (Decl);
6086 Set_Is_Intrinsic_Subprogram (Op_Name);
6089 Set_Has_Completion (Op_Name);
6090 Set_Corresponding_Equality (Op_Name, S);
6091 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
6093 end Make_Inequality_Operator;
6095 ----------------------
6096 -- May_Need_Actuals --
6097 ----------------------
6099 procedure May_Need_Actuals (Fun : Entity_Id) is
6104 F := First_Formal (Fun);
6106 while Present (F) loop
6107 if No (Default_Value (F)) then
6115 Set_Needs_No_Actuals (Fun, B);
6116 end May_Need_Actuals;
6118 ---------------------
6119 -- Mode_Conformant --
6120 ---------------------
6122 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6125 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
6127 end Mode_Conformant;
6129 ---------------------------
6130 -- New_Overloaded_Entity --
6131 ---------------------------
6133 procedure New_Overloaded_Entity
6135 Derived_Type : Entity_Id := Empty)
6137 Overridden_Subp : Entity_Id := Empty;
6138 -- Set if the current scope has an operation that is type-conformant
6139 -- with S, and becomes hidden by S.
6141 Is_Primitive_Subp : Boolean;
6142 -- Set to True if the new subprogram is primitive
6145 -- Entity that S overrides
6147 Prev_Vis : Entity_Id := Empty;
6148 -- Predecessor of E in Homonym chain
6150 procedure Check_For_Primitive_Subprogram
6151 (Is_Primitive : out Boolean;
6152 Is_Overriding : Boolean := False);
6153 -- If the subprogram being analyzed is a primitive operation of the type
6154 -- of a formal or result, set the Has_Primitive_Operations flag on the
6155 -- type, and set Is_Primitive to True (otherwise set to False). Set the
6156 -- corresponding flag on the entity itself for later use.
6158 procedure Check_Synchronized_Overriding
6159 (Def_Id : Entity_Id;
6160 First_Hom : Entity_Id;
6161 Overridden_Subp : out Entity_Id);
6162 -- First determine if Def_Id is an entry or a subprogram either defined
6163 -- in the scope of a task or protected type, or is a primitive of such
6164 -- a type. Check whether Def_Id overrides a subprogram of an interface
6165 -- implemented by the synchronized type, return the overridden entity
6168 function Is_Private_Declaration (E : Entity_Id) return Boolean;
6169 -- Check that E is declared in the private part of the current package,
6170 -- or in the package body, where it may hide a previous declaration.
6171 -- We can't use In_Private_Part by itself because this flag is also
6172 -- set when freezing entities, so we must examine the place of the
6173 -- declaration in the tree, and recognize wrapper packages as well.
6175 ------------------------------------
6176 -- Check_For_Primitive_Subprogram --
6177 ------------------------------------
6179 procedure Check_For_Primitive_Subprogram
6180 (Is_Primitive : out Boolean;
6181 Is_Overriding : Boolean := False)
6187 function Visible_Part_Type (T : Entity_Id) return Boolean;
6188 -- Returns true if T is declared in the visible part of
6189 -- the current package scope; otherwise returns false.
6190 -- Assumes that T is declared in a package.
6192 procedure Check_Private_Overriding (T : Entity_Id);
6193 -- Checks that if a primitive abstract subprogram of a visible
6194 -- abstract type is declared in a private part, then it must
6195 -- override an abstract subprogram declared in the visible part.
6196 -- Also checks that if a primitive function with a controlling
6197 -- result is declared in a private part, then it must override
6198 -- a function declared in the visible part.
6200 ------------------------------
6201 -- Check_Private_Overriding --
6202 ------------------------------
6204 procedure Check_Private_Overriding (T : Entity_Id) is
6206 if Ekind (Current_Scope) = E_Package
6207 and then In_Private_Part (Current_Scope)
6208 and then Visible_Part_Type (T)
6209 and then not In_Instance
6211 if Is_Abstract_Type (T)
6212 and then Is_Abstract_Subprogram (S)
6213 and then (not Is_Overriding
6214 or else not Is_Abstract_Subprogram (E))
6216 Error_Msg_N ("abstract subprograms must be visible "
6217 & "(RM 3.9.3(10))!", S);
6219 elsif Ekind (S) = E_Function
6220 and then Is_Tagged_Type (T)
6221 and then T = Base_Type (Etype (S))
6222 and then not Is_Overriding
6225 ("private function with tagged result must"
6226 & " override visible-part function", S);
6228 ("\move subprogram to the visible part"
6229 & " (RM 3.9.3(10))", S);
6232 end Check_Private_Overriding;
6234 -----------------------
6235 -- Visible_Part_Type --
6236 -----------------------
6238 function Visible_Part_Type (T : Entity_Id) return Boolean is
6239 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
6243 -- If the entity is a private type, then it must be
6244 -- declared in a visible part.
6246 if Ekind (T) in Private_Kind then
6250 -- Otherwise, we traverse the visible part looking for its
6251 -- corresponding declaration. We cannot use the declaration
6252 -- node directly because in the private part the entity of a
6253 -- private type is the one in the full view, which does not
6254 -- indicate that it is the completion of something visible.
6256 N := First (Visible_Declarations (Specification (P)));
6257 while Present (N) loop
6258 if Nkind (N) = N_Full_Type_Declaration
6259 and then Present (Defining_Identifier (N))
6260 and then T = Defining_Identifier (N)
6264 elsif Nkind_In (N, N_Private_Type_Declaration,
6265 N_Private_Extension_Declaration)
6266 and then Present (Defining_Identifier (N))
6267 and then T = Full_View (Defining_Identifier (N))
6276 end Visible_Part_Type;
6278 -- Start of processing for Check_For_Primitive_Subprogram
6281 Is_Primitive := False;
6283 if not Comes_From_Source (S) then
6286 -- If subprogram is at library level, it is not primitive operation
6288 elsif Current_Scope = Standard_Standard then
6291 elsif ((Ekind (Current_Scope) = E_Package
6292 or else Ekind (Current_Scope) = E_Generic_Package)
6293 and then not In_Package_Body (Current_Scope))
6294 or else Is_Overriding
6296 -- For function, check return type
6298 if Ekind (S) = E_Function then
6299 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
6300 F_Typ := Designated_Type (Etype (S));
6305 B_Typ := Base_Type (F_Typ);
6307 if Scope (B_Typ) = Current_Scope
6308 and then not Is_Class_Wide_Type (B_Typ)
6309 and then not Is_Generic_Type (B_Typ)
6311 Is_Primitive := True;
6312 Set_Has_Primitive_Operations (B_Typ);
6313 Set_Is_Primitive (S);
6314 Check_Private_Overriding (B_Typ);
6318 -- For all subprograms, check formals
6320 Formal := First_Formal (S);
6321 while Present (Formal) loop
6322 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
6323 F_Typ := Designated_Type (Etype (Formal));
6325 F_Typ := Etype (Formal);
6328 B_Typ := Base_Type (F_Typ);
6330 if Ekind (B_Typ) = E_Access_Subtype then
6331 B_Typ := Base_Type (B_Typ);
6334 if Scope (B_Typ) = Current_Scope
6335 and then not Is_Class_Wide_Type (B_Typ)
6336 and then not Is_Generic_Type (B_Typ)
6338 Is_Primitive := True;
6339 Set_Is_Primitive (S);
6340 Set_Has_Primitive_Operations (B_Typ);
6341 Check_Private_Overriding (B_Typ);
6344 Next_Formal (Formal);
6347 end Check_For_Primitive_Subprogram;
6349 -----------------------------------
6350 -- Check_Synchronized_Overriding --
6351 -----------------------------------
6353 procedure Check_Synchronized_Overriding
6354 (Def_Id : Entity_Id;
6355 First_Hom : Entity_Id;
6356 Overridden_Subp : out Entity_Id)
6358 Formal_Typ : Entity_Id;
6359 Ifaces_List : Elist_Id;
6364 Overridden_Subp := Empty;
6366 -- Def_Id must be an entry or a subprogram
6368 if Ekind (Def_Id) /= E_Entry
6369 and then Ekind (Def_Id) /= E_Function
6370 and then Ekind (Def_Id) /= E_Procedure
6375 -- Search for the concurrent declaration since it contains the list
6376 -- of all implemented interfaces. In this case, the subprogram is
6377 -- declared within the scope of a protected or a task type.
6379 if Present (Scope (Def_Id))
6380 and then Is_Concurrent_Type (Scope (Def_Id))
6381 and then not Is_Generic_Actual_Type (Scope (Def_Id))
6383 Typ := Scope (Def_Id);
6386 -- The subprogram may be a primitive of a concurrent type
6388 elsif Present (First_Formal (Def_Id)) then
6389 Formal_Typ := Etype (First_Formal (Def_Id));
6391 if Is_Concurrent_Type (Formal_Typ)
6392 and then not Is_Generic_Actual_Type (Formal_Typ)
6397 -- This case occurs when the concurrent type is declared within
6398 -- a generic unit. As a result the corresponding record has been
6399 -- built and used as the type of the first formal, we just have
6400 -- to retrieve the corresponding concurrent type.
6402 elsif Is_Concurrent_Record_Type (Formal_Typ)
6403 and then Present (Corresponding_Concurrent_Type (Formal_Typ))
6405 Typ := Corresponding_Concurrent_Type (Formal_Typ);
6415 -- Gather all limited, protected and task interfaces that Typ
6416 -- implements. There is no overriding to check if is an inherited
6417 -- operation in a type derivation on for a generic actual.
6419 if Nkind (Parent (Typ)) /= N_Full_Type_Declaration
6421 not Nkind_In (Parent (Def_Id), N_Subtype_Declaration,
6422 N_Task_Type_Declaration,
6423 N_Protected_Type_Declaration)
6425 Collect_Abstract_Interfaces (Typ, Ifaces_List);
6427 if not Is_Empty_Elmt_List (Ifaces_List) then
6429 Find_Overridden_Synchronized_Primitive
6430 (Def_Id, First_Hom, Ifaces_List, In_Scope);
6433 end Check_Synchronized_Overriding;
6435 ----------------------------
6436 -- Is_Private_Declaration --
6437 ----------------------------
6439 function Is_Private_Declaration (E : Entity_Id) return Boolean is
6440 Priv_Decls : List_Id;
6441 Decl : constant Node_Id := Unit_Declaration_Node (E);
6444 if Is_Package_Or_Generic_Package (Current_Scope)
6445 and then In_Private_Part (Current_Scope)
6448 Private_Declarations (
6449 Specification (Unit_Declaration_Node (Current_Scope)));
6451 return In_Package_Body (Current_Scope)
6453 (Is_List_Member (Decl)
6454 and then List_Containing (Decl) = Priv_Decls)
6455 or else (Nkind (Parent (Decl)) = N_Package_Specification
6456 and then not Is_Compilation_Unit (
6457 Defining_Entity (Parent (Decl)))
6458 and then List_Containing (Parent (Parent (Decl)))
6463 end Is_Private_Declaration;
6465 -- Start of processing for New_Overloaded_Entity
6468 -- We need to look for an entity that S may override. This must be a
6469 -- homonym in the current scope, so we look for the first homonym of
6470 -- S in the current scope as the starting point for the search.
6472 E := Current_Entity_In_Scope (S);
6474 -- If there is no homonym then this is definitely not overriding
6477 Enter_Overloaded_Entity (S);
6478 Check_Dispatching_Operation (S, Empty);
6479 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6481 -- If subprogram has an explicit declaration, check whether it
6482 -- has an overriding indicator.
6484 if Comes_From_Source (S) then
6485 Check_Synchronized_Overriding (S, Homonym (S), Overridden_Subp);
6486 Check_Overriding_Indicator
6487 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6490 -- If there is a homonym that is not overloadable, then we have an
6491 -- error, except for the special cases checked explicitly below.
6493 elsif not Is_Overloadable (E) then
6495 -- Check for spurious conflict produced by a subprogram that has the
6496 -- same name as that of the enclosing generic package. The conflict
6497 -- occurs within an instance, between the subprogram and the renaming
6498 -- declaration for the package. After the subprogram, the package
6499 -- renaming declaration becomes hidden.
6501 if Ekind (E) = E_Package
6502 and then Present (Renamed_Object (E))
6503 and then Renamed_Object (E) = Current_Scope
6504 and then Nkind (Parent (Renamed_Object (E))) =
6505 N_Package_Specification
6506 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
6509 Set_Is_Immediately_Visible (E, False);
6510 Enter_Overloaded_Entity (S);
6511 Set_Homonym (S, Homonym (E));
6512 Check_Dispatching_Operation (S, Empty);
6513 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
6515 -- If the subprogram is implicit it is hidden by the previous
6516 -- declaration. However if it is dispatching, it must appear in the
6517 -- dispatch table anyway, because it can be dispatched to even if it
6518 -- cannot be called directly.
6520 elsif Present (Alias (S))
6521 and then not Comes_From_Source (S)
6523 Set_Scope (S, Current_Scope);
6525 if Is_Dispatching_Operation (Alias (S)) then
6526 Check_Dispatching_Operation (S, Empty);
6532 Error_Msg_Sloc := Sloc (E);
6534 -- Generate message, with useful additional warning if in generic
6536 if Is_Generic_Unit (E) then
6537 Error_Msg_N ("previous generic unit cannot be overloaded", S);
6538 Error_Msg_N ("\& conflicts with declaration#", S);
6540 Error_Msg_N ("& conflicts with declaration#", S);
6546 -- E exists and is overloadable
6549 -- Ada 2005 (AI-251): Derivation of abstract interface primitives
6550 -- need no check against the homonym chain. They are directly added
6551 -- to the list of primitive operations of Derived_Type.
6553 if Ada_Version >= Ada_05
6554 and then Present (Derived_Type)
6555 and then Is_Dispatching_Operation (Alias (S))
6556 and then Present (Find_Dispatching_Type (Alias (S)))
6557 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
6558 and then not Is_Predefined_Dispatching_Operation (Alias (S))
6560 goto Add_New_Entity;
6563 Check_Synchronized_Overriding (S, E, Overridden_Subp);
6565 -- Loop through E and its homonyms to determine if any of them is
6566 -- the candidate for overriding by S.
6568 while Present (E) loop
6570 -- Definitely not interesting if not in the current scope
6572 if Scope (E) /= Current_Scope then
6575 -- Check if we have type conformance
6577 elsif Type_Conformant (E, S) then
6579 -- If the old and new entities have the same profile and one
6580 -- is not the body of the other, then this is an error, unless
6581 -- one of them is implicitly declared.
6583 -- There are some cases when both can be implicit, for example
6584 -- when both a literal and a function that overrides it are
6585 -- inherited in a derivation, or when an inherited operation
6586 -- of a tagged full type overrides the inherited operation of
6587 -- a private extension. Ada 83 had a special rule for the
6588 -- literal case. In Ada95, the later implicit operation hides
6589 -- the former, and the literal is always the former. In the
6590 -- odd case where both are derived operations declared at the
6591 -- same point, both operations should be declared, and in that
6592 -- case we bypass the following test and proceed to the next
6593 -- part (this can only occur for certain obscure cases
6594 -- involving homographs in instances and can't occur for
6595 -- dispatching operations ???). Note that the following
6596 -- condition is less than clear. For example, it's not at all
6597 -- clear why there's a test for E_Entry here. ???
6599 if Present (Alias (S))
6600 and then (No (Alias (E))
6601 or else Comes_From_Source (E)
6602 or else Is_Dispatching_Operation (E))
6604 (Ekind (E) = E_Entry
6605 or else Ekind (E) /= E_Enumeration_Literal)
6607 -- When an derived operation is overloaded it may be due to
6608 -- the fact that the full view of a private extension
6609 -- re-inherits. It has to be dealt with.
6611 if Is_Package_Or_Generic_Package (Current_Scope)
6612 and then In_Private_Part (Current_Scope)
6614 Check_Operation_From_Private_View (S, E);
6617 -- In any case the implicit operation remains hidden by
6618 -- the existing declaration, which is overriding.
6620 Set_Is_Overriding_Operation (E);
6622 if Comes_From_Source (E) then
6623 Check_Overriding_Indicator (E, S, Is_Primitive => False);
6625 -- Indicate that E overrides the operation from which
6628 if Present (Alias (S)) then
6629 Set_Overridden_Operation (E, Alias (S));
6631 Set_Overridden_Operation (E, S);
6637 -- Within an instance, the renaming declarations for
6638 -- actual subprograms may become ambiguous, but they do
6639 -- not hide each other.
6641 elsif Ekind (E) /= E_Entry
6642 and then not Comes_From_Source (E)
6643 and then not Is_Generic_Instance (E)
6644 and then (Present (Alias (E))
6645 or else Is_Intrinsic_Subprogram (E))
6646 and then (not In_Instance
6647 or else No (Parent (E))
6648 or else Nkind (Unit_Declaration_Node (E)) /=
6649 N_Subprogram_Renaming_Declaration)
6651 -- A subprogram child unit is not allowed to override
6652 -- an inherited subprogram (10.1.1(20)).
6654 if Is_Child_Unit (S) then
6656 ("child unit overrides inherited subprogram in parent",
6661 if Is_Non_Overriding_Operation (E, S) then
6662 Enter_Overloaded_Entity (S);
6663 if No (Derived_Type)
6664 or else Is_Tagged_Type (Derived_Type)
6666 Check_Dispatching_Operation (S, Empty);
6672 -- E is a derived operation or an internal operator which
6673 -- is being overridden. Remove E from further visibility.
6674 -- Furthermore, if E is a dispatching operation, it must be
6675 -- replaced in the list of primitive operations of its type
6676 -- (see Override_Dispatching_Operation).
6678 Overridden_Subp := E;
6684 Prev := First_Entity (Current_Scope);
6686 while Present (Prev)
6687 and then Next_Entity (Prev) /= E
6692 -- It is possible for E to be in the current scope and
6693 -- yet not in the entity chain. This can only occur in a
6694 -- generic context where E is an implicit concatenation
6695 -- in the formal part, because in a generic body the
6696 -- entity chain starts with the formals.
6699 (Present (Prev) or else Chars (E) = Name_Op_Concat);
6701 -- E must be removed both from the entity_list of the
6702 -- current scope, and from the visibility chain
6704 if Debug_Flag_E then
6705 Write_Str ("Override implicit operation ");
6706 Write_Int (Int (E));
6710 -- If E is a predefined concatenation, it stands for four
6711 -- different operations. As a result, a single explicit
6712 -- declaration does not hide it. In a possible ambiguous
6713 -- situation, Disambiguate chooses the user-defined op,
6714 -- so it is correct to retain the previous internal one.
6716 if Chars (E) /= Name_Op_Concat
6717 or else Ekind (E) /= E_Operator
6719 -- For nondispatching derived operations that are
6720 -- overridden by a subprogram declared in the private
6721 -- part of a package, we retain the derived
6722 -- subprogram but mark it as not immediately visible.
6723 -- If the derived operation was declared in the
6724 -- visible part then this ensures that it will still
6725 -- be visible outside the package with the proper
6726 -- signature (calls from outside must also be
6727 -- directed to this version rather than the
6728 -- overriding one, unlike the dispatching case).
6729 -- Calls from inside the package will still resolve
6730 -- to the overriding subprogram since the derived one
6731 -- is marked as not visible within the package.
6733 -- If the private operation is dispatching, we achieve
6734 -- the overriding by keeping the implicit operation
6735 -- but setting its alias to be the overriding one. In
6736 -- this fashion the proper body is executed in all
6737 -- cases, but the original signature is used outside
6740 -- If the overriding is not in the private part, we
6741 -- remove the implicit operation altogether.
6743 if Is_Private_Declaration (S) then
6745 if not Is_Dispatching_Operation (E) then
6746 Set_Is_Immediately_Visible (E, False);
6748 -- Work done in Override_Dispatching_Operation,
6749 -- so nothing else need to be done here.
6755 -- Find predecessor of E in Homonym chain
6757 if E = Current_Entity (E) then
6760 Prev_Vis := Current_Entity (E);
6761 while Homonym (Prev_Vis) /= E loop
6762 Prev_Vis := Homonym (Prev_Vis);
6766 if Prev_Vis /= Empty then
6768 -- Skip E in the visibility chain
6770 Set_Homonym (Prev_Vis, Homonym (E));
6773 Set_Name_Entity_Id (Chars (E), Homonym (E));
6776 Set_Next_Entity (Prev, Next_Entity (E));
6778 if No (Next_Entity (Prev)) then
6779 Set_Last_Entity (Current_Scope, Prev);
6785 Enter_Overloaded_Entity (S);
6786 Set_Is_Overriding_Operation (S);
6787 Check_Overriding_Indicator (S, E, Is_Primitive => True);
6789 -- Indicate that S overrides the operation from which
6792 if Comes_From_Source (S) then
6793 if Present (Alias (E)) then
6794 Set_Overridden_Operation (S, Alias (E));
6796 Set_Overridden_Operation (S, E);
6800 if Is_Dispatching_Operation (E) then
6802 -- An overriding dispatching subprogram inherits the
6803 -- convention of the overridden subprogram (by
6806 Set_Convention (S, Convention (E));
6807 Check_Dispatching_Operation (S, E);
6810 Check_Dispatching_Operation (S, Empty);
6813 Check_For_Primitive_Subprogram
6814 (Is_Primitive_Subp, Is_Overriding => True);
6815 goto Check_Inequality;
6818 -- Apparent redeclarations in instances can occur when two
6819 -- formal types get the same actual type. The subprograms in
6820 -- in the instance are legal, even if not callable from the
6821 -- outside. Calls from within are disambiguated elsewhere.
6822 -- For dispatching operations in the visible part, the usual
6823 -- rules apply, and operations with the same profile are not
6826 elsif (In_Instance_Visible_Part
6827 and then not Is_Dispatching_Operation (E))
6828 or else In_Instance_Not_Visible
6832 -- Here we have a real error (identical profile)
6835 Error_Msg_Sloc := Sloc (E);
6837 -- Avoid cascaded errors if the entity appears in
6838 -- subsequent calls.
6840 Set_Scope (S, Current_Scope);
6842 -- Generate error, with extra useful warning for the case
6843 -- of a generic instance with no completion.
6845 if Is_Generic_Instance (S)
6846 and then not Has_Completion (E)
6849 ("instantiation cannot provide body for&", S);
6850 Error_Msg_N ("\& conflicts with declaration#", S);
6852 Error_Msg_N ("& conflicts with declaration#", S);
6859 -- If one subprogram has an access parameter and the other
6860 -- a parameter of an access type, calls to either might be
6861 -- ambiguous. Verify that parameters match except for the
6862 -- access parameter.
6864 if May_Hide_Profile then
6869 F1 := First_Formal (S);
6870 F2 := First_Formal (E);
6871 while Present (F1) and then Present (F2) loop
6872 if Is_Access_Type (Etype (F1)) then
6873 if not Is_Access_Type (Etype (F2))
6874 or else not Conforming_Types
6875 (Designated_Type (Etype (F1)),
6876 Designated_Type (Etype (F2)),
6879 May_Hide_Profile := False;
6883 not Conforming_Types
6884 (Etype (F1), Etype (F2), Type_Conformant)
6886 May_Hide_Profile := False;
6897 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
6908 -- On exit, we know that S is a new entity
6910 Enter_Overloaded_Entity (S);
6911 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6912 Check_Overriding_Indicator
6913 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6915 -- If S is a derived operation for an untagged type then by
6916 -- definition it's not a dispatching operation (even if the parent
6917 -- operation was dispatching), so we don't call
6918 -- Check_Dispatching_Operation in that case.
6920 if No (Derived_Type)
6921 or else Is_Tagged_Type (Derived_Type)
6923 Check_Dispatching_Operation (S, Empty);
6927 -- If this is a user-defined equality operator that is not a derived
6928 -- subprogram, create the corresponding inequality. If the operation is
6929 -- dispatching, the expansion is done elsewhere, and we do not create
6930 -- an explicit inequality operation.
6932 <<Check_Inequality>>
6933 if Chars (S) = Name_Op_Eq
6934 and then Etype (S) = Standard_Boolean
6935 and then Present (Parent (S))
6936 and then not Is_Dispatching_Operation (S)
6938 Make_Inequality_Operator (S);
6940 end New_Overloaded_Entity;
6942 ---------------------
6943 -- Process_Formals --
6944 ---------------------
6946 procedure Process_Formals
6948 Related_Nod : Node_Id)
6950 Param_Spec : Node_Id;
6952 Formal_Type : Entity_Id;
6956 Num_Out_Params : Nat := 0;
6957 First_Out_Param : Entity_Id := Empty;
6958 -- Used for setting Is_Only_Out_Parameter
6960 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
6961 -- Check whether the default has a class-wide type. After analysis the
6962 -- default has the type of the formal, so we must also check explicitly
6963 -- for an access attribute.
6965 ---------------------------
6966 -- Is_Class_Wide_Default --
6967 ---------------------------
6969 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
6971 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
6972 or else (Nkind (D) = N_Attribute_Reference
6973 and then Attribute_Name (D) = Name_Access
6974 and then Is_Class_Wide_Type (Etype (Prefix (D))));
6975 end Is_Class_Wide_Default;
6977 -- Start of processing for Process_Formals
6980 -- In order to prevent premature use of the formals in the same formal
6981 -- part, the Ekind is left undefined until all default expressions are
6982 -- analyzed. The Ekind is established in a separate loop at the end.
6984 Param_Spec := First (T);
6985 while Present (Param_Spec) loop
6986 Formal := Defining_Identifier (Param_Spec);
6987 Set_Never_Set_In_Source (Formal, True);
6988 Enter_Name (Formal);
6990 -- Case of ordinary parameters
6992 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
6993 Find_Type (Parameter_Type (Param_Spec));
6994 Ptype := Parameter_Type (Param_Spec);
6996 if Ptype = Error then
7000 Formal_Type := Entity (Ptype);
7002 if Is_Incomplete_Type (Formal_Type)
7004 (Is_Class_Wide_Type (Formal_Type)
7005 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
7007 -- Ada 2005 (AI-326): Tagged incomplete types allowed
7009 if Is_Tagged_Type (Formal_Type) then
7012 -- Special handling of Value_Type for CIL case
7014 elsif Is_Value_Type (Formal_Type) then
7017 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
7018 N_Access_Procedure_Definition)
7020 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
7022 -- An incomplete type that is not tagged is allowed in an
7023 -- access-to-subprogram type only if it is a local declaration
7024 -- with a forthcoming completion (3.10.1 (9.2/2)).
7026 elsif Scope (Formal_Type) /= Scope (Current_Scope) then
7028 ("invalid use of limited view of type", Param_Spec);
7031 elsif Ekind (Formal_Type) = E_Void then
7032 Error_Msg_NE ("premature use of&",
7033 Parameter_Type (Param_Spec), Formal_Type);
7036 -- Ada 2005 (AI-231): Create and decorate an internal subtype
7037 -- declaration corresponding to the null-excluding type of the
7038 -- formal in the enclosing scope. Finally, replace the parameter
7039 -- type of the formal with the internal subtype.
7041 if Ada_Version >= Ada_05
7042 and then Null_Exclusion_Present (Param_Spec)
7044 if not Is_Access_Type (Formal_Type) then
7046 ("`NOT NULL` allowed only for an access type", Param_Spec);
7049 if Can_Never_Be_Null (Formal_Type)
7050 and then Comes_From_Source (Related_Nod)
7053 ("`NOT NULL` not allowed (& already excludes null)",
7059 Create_Null_Excluding_Itype
7061 Related_Nod => Related_Nod,
7062 Scope_Id => Scope (Current_Scope));
7064 -- If the designated type of the itype is an itype we
7065 -- decorate it with the Has_Delayed_Freeze attribute to
7066 -- avoid problems with the backend.
7069 -- type T is access procedure;
7070 -- procedure Op (O : not null T);
7072 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
7073 Set_Has_Delayed_Freeze (Formal_Type);
7078 -- An access formal type
7082 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
7084 -- No need to continue if we already notified errors
7086 if not Present (Formal_Type) then
7090 -- Ada 2005 (AI-254)
7093 AD : constant Node_Id :=
7094 Access_To_Subprogram_Definition
7095 (Parameter_Type (Param_Spec));
7097 if Present (AD) and then Protected_Present (AD) then
7099 Replace_Anonymous_Access_To_Protected_Subprogram
7105 Set_Etype (Formal, Formal_Type);
7106 Default := Expression (Param_Spec);
7108 if Present (Default) then
7109 if Out_Present (Param_Spec) then
7111 ("default initialization only allowed for IN parameters",
7115 -- Do the special preanalysis of the expression (see section on
7116 -- "Handling of Default Expressions" in the spec of package Sem).
7118 Preanalyze_Spec_Expression (Default, Formal_Type);
7120 -- An access to constant cannot be the default for
7121 -- an access parameter that is an access to variable.
7123 if Ekind (Formal_Type) = E_Anonymous_Access_Type
7124 and then not Is_Access_Constant (Formal_Type)
7125 and then Is_Access_Type (Etype (Default))
7126 and then Is_Access_Constant (Etype (Default))
7129 ("formal that is access to variable cannot be initialized " &
7130 "with an access-to-constant expression", Default);
7133 -- Check that the designated type of an access parameter's default
7134 -- is not a class-wide type unless the parameter's designated type
7135 -- is also class-wide.
7137 if Ekind (Formal_Type) = E_Anonymous_Access_Type
7138 and then not From_With_Type (Formal_Type)
7139 and then Is_Class_Wide_Default (Default)
7140 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
7143 ("access to class-wide expression not allowed here", Default);
7147 -- Ada 2005 (AI-231): Static checks
7149 if Ada_Version >= Ada_05
7150 and then Is_Access_Type (Etype (Formal))
7151 and then Can_Never_Be_Null (Etype (Formal))
7153 Null_Exclusion_Static_Checks (Param_Spec);
7160 -- If this is the formal part of a function specification, analyze the
7161 -- subtype mark in the context where the formals are visible but not
7162 -- yet usable, and may hide outer homographs.
7164 if Nkind (Related_Nod) = N_Function_Specification then
7165 Analyze_Return_Type (Related_Nod);
7168 -- Now set the kind (mode) of each formal
7170 Param_Spec := First (T);
7172 while Present (Param_Spec) loop
7173 Formal := Defining_Identifier (Param_Spec);
7174 Set_Formal_Mode (Formal);
7176 if Ekind (Formal) = E_In_Parameter then
7177 Set_Default_Value (Formal, Expression (Param_Spec));
7179 if Present (Expression (Param_Spec)) then
7180 Default := Expression (Param_Spec);
7182 if Is_Scalar_Type (Etype (Default)) then
7184 (Parameter_Type (Param_Spec)) /= N_Access_Definition
7186 Formal_Type := Entity (Parameter_Type (Param_Spec));
7189 Formal_Type := Access_Definition
7190 (Related_Nod, Parameter_Type (Param_Spec));
7193 Apply_Scalar_Range_Check (Default, Formal_Type);
7197 elsif Ekind (Formal) = E_Out_Parameter then
7198 Num_Out_Params := Num_Out_Params + 1;
7200 if Num_Out_Params = 1 then
7201 First_Out_Param := Formal;
7204 elsif Ekind (Formal) = E_In_Out_Parameter then
7205 Num_Out_Params := Num_Out_Params + 1;
7211 if Present (First_Out_Param) and then Num_Out_Params = 1 then
7212 Set_Is_Only_Out_Parameter (First_Out_Param);
7214 end Process_Formals;
7220 procedure Process_PPCs
7222 Spec_Id : Entity_Id;
7223 Body_Id : Entity_Id)
7225 Loc : constant Source_Ptr := Sloc (N);
7227 Plist : List_Id := No_List;
7231 function Grab_PPC (Nam : Name_Id) return Node_Id;
7232 -- Prag contains an analyzed precondition or postcondition pragma.
7233 -- This function copies the pragma, changes it to the corresponding
7234 -- Check pragma and returns the Check pragma as the result. The
7235 -- argument Nam is either Name_Precondition or Name_Postcondition.
7241 function Grab_PPC (Nam : Name_Id) return Node_Id is
7242 CP : constant Node_Id := New_Copy_Tree (Prag);
7245 -- Set Analyzed to false, since we want to reanalyze the check
7246 -- procedure. Note that it is only at the outer level that we
7247 -- do this fiddling, for the spec cases, the already preanalyzed
7248 -- parameters are not affected.
7250 Set_Analyzed (CP, False);
7252 -- Change pragma into corresponding pragma Check
7254 Prepend_To (Pragma_Argument_Associations (CP),
7255 Make_Pragma_Argument_Association (Sloc (Prag),
7257 Make_Identifier (Loc,
7259 Set_Pragma_Identifier (CP,
7260 Make_Identifier (Sloc (Prag),
7261 Chars => Name_Check));
7266 -- Start of processing for Process_PPCs
7269 -- Grab preconditions from spec
7271 if Present (Spec_Id) then
7273 -- Loop through PPC pragmas from spec. Note that preconditions from
7274 -- the body will be analyzed and converted when we scan the body
7275 -- declarations below.
7277 Prag := Spec_PPC_List (Spec_Id);
7278 while Present (Prag) loop
7279 if Pragma_Name (Prag) = Name_Precondition
7280 and then PPC_Enabled (Prag)
7282 -- Add pragma Check at the start of the declarations of N.
7283 -- Note that this processing reverses the order of the list,
7284 -- which is what we want since new entries were chained to
7285 -- the head of the list.
7287 Prepend (Grab_PPC (Name_Precondition), Declarations (N));
7290 Prag := Next_Pragma (Prag);
7294 -- Build postconditions procedure if needed and prepend the following
7295 -- declaration to the start of the declarations for the subprogram.
7297 -- procedure _postconditions [(_Result : resulttype)] is
7299 -- pragma Check (Postcondition, condition [,message]);
7300 -- pragma Check (Postcondition, condition [,message]);
7304 -- First we deal with the postconditions in the body
7306 if Is_Non_Empty_List (Declarations (N)) then
7308 -- Loop through declarations
7310 Prag := First (Declarations (N));
7311 while Present (Prag) loop
7312 if Nkind (Prag) = N_Pragma then
7314 -- If pragma, capture if enabled postcondition, else ignore
7316 if Pragma_Name (Prag) = Name_Postcondition
7317 and then Check_Enabled (Name_Postcondition)
7319 if Plist = No_List then
7320 Plist := Empty_List;
7324 Append (Grab_PPC (Name_Postcondition), Plist);
7329 -- Not a pragma, if comes from source, then end scan
7331 elsif Comes_From_Source (Prag) then
7334 -- Skip stuff not coming from source
7342 -- Now deal with any postconditions from the spec
7344 if Present (Spec_Id) then
7346 -- Loop through PPC pragmas from spec
7348 Prag := Spec_PPC_List (Spec_Id);
7349 while Present (Prag) loop
7350 if Pragma_Name (Prag) = Name_Postcondition
7351 and then PPC_Enabled (Prag)
7353 if Plist = No_List then
7354 Plist := Empty_List;
7357 Append (Grab_PPC (Name_Postcondition), Plist);
7360 Prag := Next_Pragma (Prag);
7364 -- If we had any postconditions, build the procedure
7366 if Present (Plist) then
7367 Subp := Defining_Entity (N);
7369 if Etype (Subp) /= Standard_Void_Type then
7371 Make_Parameter_Specification (Loc,
7372 Defining_Identifier =>
7373 Make_Defining_Identifier (Loc,
7374 Chars => Name_uResult),
7375 Parameter_Type => New_Occurrence_Of (Etype (Subp), Loc)));
7380 Prepend_To (Declarations (N),
7381 Make_Subprogram_Body (Loc,
7383 Make_Procedure_Specification (Loc,
7384 Defining_Unit_Name =>
7385 Make_Defining_Identifier (Loc,
7386 Chars => Name_uPostconditions),
7387 Parameter_Specifications => Parms),
7389 Declarations => Empty_List,
7391 Handled_Statement_Sequence =>
7392 Make_Handled_Sequence_Of_Statements (Loc,
7393 Statements => Plist)));
7395 if Present (Spec_Id) then
7396 Set_Has_Postconditions (Spec_Id);
7398 Set_Has_Postconditions (Body_Id);
7403 ----------------------------
7404 -- Reference_Body_Formals --
7405 ----------------------------
7407 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
7412 if Error_Posted (Spec) then
7416 -- Iterate over both lists. They may be of different lengths if the two
7417 -- specs are not conformant.
7419 Fs := First_Formal (Spec);
7420 Fb := First_Formal (Bod);
7421 while Present (Fs) and then Present (Fb) loop
7422 Generate_Reference (Fs, Fb, 'b');
7425 Style.Check_Identifier (Fb, Fs);
7428 Set_Spec_Entity (Fb, Fs);
7429 Set_Referenced (Fs, False);
7433 end Reference_Body_Formals;
7435 -------------------------
7436 -- Set_Actual_Subtypes --
7437 -------------------------
7439 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
7440 Loc : constant Source_Ptr := Sloc (N);
7444 First_Stmt : Node_Id := Empty;
7445 AS_Needed : Boolean;
7448 -- If this is an empty initialization procedure, no need to create
7449 -- actual subtypes (small optimization).
7451 if Ekind (Subp) = E_Procedure
7452 and then Is_Null_Init_Proc (Subp)
7457 Formal := First_Formal (Subp);
7458 while Present (Formal) loop
7459 T := Etype (Formal);
7461 -- We never need an actual subtype for a constrained formal
7463 if Is_Constrained (T) then
7466 -- If we have unknown discriminants, then we do not need an actual
7467 -- subtype, or more accurately we cannot figure it out! Note that
7468 -- all class-wide types have unknown discriminants.
7470 elsif Has_Unknown_Discriminants (T) then
7473 -- At this stage we have an unconstrained type that may need an
7474 -- actual subtype. For sure the actual subtype is needed if we have
7475 -- an unconstrained array type.
7477 elsif Is_Array_Type (T) then
7480 -- The only other case needing an actual subtype is an unconstrained
7481 -- record type which is an IN parameter (we cannot generate actual
7482 -- subtypes for the OUT or IN OUT case, since an assignment can
7483 -- change the discriminant values. However we exclude the case of
7484 -- initialization procedures, since discriminants are handled very
7485 -- specially in this context, see the section entitled "Handling of
7486 -- Discriminants" in Einfo.
7488 -- We also exclude the case of Discrim_SO_Functions (functions used
7489 -- in front end layout mode for size/offset values), since in such
7490 -- functions only discriminants are referenced, and not only are such
7491 -- subtypes not needed, but they cannot always be generated, because
7492 -- of order of elaboration issues.
7494 elsif Is_Record_Type (T)
7495 and then Ekind (Formal) = E_In_Parameter
7496 and then Chars (Formal) /= Name_uInit
7497 and then not Is_Unchecked_Union (T)
7498 and then not Is_Discrim_SO_Function (Subp)
7502 -- All other cases do not need an actual subtype
7508 -- Generate actual subtypes for unconstrained arrays and
7509 -- unconstrained discriminated records.
7512 if Nkind (N) = N_Accept_Statement then
7514 -- If expansion is active, The formal is replaced by a local
7515 -- variable that renames the corresponding entry of the
7516 -- parameter block, and it is this local variable that may
7517 -- require an actual subtype.
7519 if Expander_Active then
7520 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
7522 Decl := Build_Actual_Subtype (T, Formal);
7525 if Present (Handled_Statement_Sequence (N)) then
7527 First (Statements (Handled_Statement_Sequence (N)));
7528 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
7529 Mark_Rewrite_Insertion (Decl);
7531 -- If the accept statement has no body, there will be no
7532 -- reference to the actuals, so no need to compute actual
7539 Decl := Build_Actual_Subtype (T, Formal);
7540 Prepend (Decl, Declarations (N));
7541 Mark_Rewrite_Insertion (Decl);
7544 -- The declaration uses the bounds of an existing object, and
7545 -- therefore needs no constraint checks.
7547 Analyze (Decl, Suppress => All_Checks);
7549 -- We need to freeze manually the generated type when it is
7550 -- inserted anywhere else than in a declarative part.
7552 if Present (First_Stmt) then
7553 Insert_List_Before_And_Analyze (First_Stmt,
7554 Freeze_Entity (Defining_Identifier (Decl), Loc));
7557 if Nkind (N) = N_Accept_Statement
7558 and then Expander_Active
7560 Set_Actual_Subtype (Renamed_Object (Formal),
7561 Defining_Identifier (Decl));
7563 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
7567 Next_Formal (Formal);
7569 end Set_Actual_Subtypes;
7571 ---------------------
7572 -- Set_Formal_Mode --
7573 ---------------------
7575 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
7576 Spec : constant Node_Id := Parent (Formal_Id);
7579 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
7580 -- since we ensure that corresponding actuals are always valid at the
7581 -- point of the call.
7583 if Out_Present (Spec) then
7584 if Ekind (Scope (Formal_Id)) = E_Function
7585 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
7587 Error_Msg_N ("functions can only have IN parameters", Spec);
7588 Set_Ekind (Formal_Id, E_In_Parameter);
7590 elsif In_Present (Spec) then
7591 Set_Ekind (Formal_Id, E_In_Out_Parameter);
7594 Set_Ekind (Formal_Id, E_Out_Parameter);
7595 Set_Never_Set_In_Source (Formal_Id, True);
7596 Set_Is_True_Constant (Formal_Id, False);
7597 Set_Current_Value (Formal_Id, Empty);
7601 Set_Ekind (Formal_Id, E_In_Parameter);
7604 -- Set Is_Known_Non_Null for access parameters since the language
7605 -- guarantees that access parameters are always non-null. We also set
7606 -- Can_Never_Be_Null, since there is no way to change the value.
7608 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
7610 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
7611 -- null; In Ada 2005, only if then null_exclusion is explicit.
7613 if Ada_Version < Ada_05
7614 or else Can_Never_Be_Null (Etype (Formal_Id))
7616 Set_Is_Known_Non_Null (Formal_Id);
7617 Set_Can_Never_Be_Null (Formal_Id);
7620 -- Ada 2005 (AI-231): Null-exclusion access subtype
7622 elsif Is_Access_Type (Etype (Formal_Id))
7623 and then Can_Never_Be_Null (Etype (Formal_Id))
7625 Set_Is_Known_Non_Null (Formal_Id);
7628 Set_Mechanism (Formal_Id, Default_Mechanism);
7629 Set_Formal_Validity (Formal_Id);
7630 end Set_Formal_Mode;
7632 -------------------------
7633 -- Set_Formal_Validity --
7634 -------------------------
7636 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
7638 -- If no validity checking, then we cannot assume anything about the
7639 -- validity of parameters, since we do not know there is any checking
7640 -- of the validity on the call side.
7642 if not Validity_Checks_On then
7645 -- If validity checking for parameters is enabled, this means we are
7646 -- not supposed to make any assumptions about argument values.
7648 elsif Validity_Check_Parameters then
7651 -- If we are checking in parameters, we will assume that the caller is
7652 -- also checking parameters, so we can assume the parameter is valid.
7654 elsif Ekind (Formal_Id) = E_In_Parameter
7655 and then Validity_Check_In_Params
7657 Set_Is_Known_Valid (Formal_Id, True);
7659 -- Similar treatment for IN OUT parameters
7661 elsif Ekind (Formal_Id) = E_In_Out_Parameter
7662 and then Validity_Check_In_Out_Params
7664 Set_Is_Known_Valid (Formal_Id, True);
7666 end Set_Formal_Validity;
7668 ------------------------
7669 -- Subtype_Conformant --
7670 ------------------------
7672 function Subtype_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7675 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result);
7677 end Subtype_Conformant;
7679 ---------------------
7680 -- Type_Conformant --
7681 ---------------------
7683 function Type_Conformant
7684 (New_Id : Entity_Id;
7686 Skip_Controlling_Formals : Boolean := False) return Boolean
7690 May_Hide_Profile := False;
7693 (New_Id, Old_Id, Type_Conformant, False, Result,
7694 Skip_Controlling_Formals => Skip_Controlling_Formals);
7696 end Type_Conformant;
7698 -------------------------------
7699 -- Valid_Operator_Definition --
7700 -------------------------------
7702 procedure Valid_Operator_Definition (Designator : Entity_Id) is
7705 Id : constant Name_Id := Chars (Designator);
7709 F := First_Formal (Designator);
7710 while Present (F) loop
7713 if Present (Default_Value (F)) then
7715 ("default values not allowed for operator parameters",
7722 -- Verify that user-defined operators have proper number of arguments
7723 -- First case of operators which can only be unary
7726 or else Id = Name_Op_Abs
7730 -- Case of operators which can be unary or binary
7732 elsif Id = Name_Op_Add
7733 or Id = Name_Op_Subtract
7735 N_OK := (N in 1 .. 2);
7737 -- All other operators can only be binary
7745 ("incorrect number of arguments for operator", Designator);
7749 and then Base_Type (Etype (Designator)) = Standard_Boolean
7750 and then not Is_Intrinsic_Subprogram (Designator)
7753 ("explicit definition of inequality not allowed", Designator);
7755 end Valid_Operator_Definition;