1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2007, 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 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Errout; use Errout;
33 with Expander; use Expander;
34 with Exp_Ch6; use Exp_Ch6;
35 with Exp_Ch7; use Exp_Ch7;
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.
101 -- Called when the return statement 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 -- subsequenty 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_Overriding_Indicator
144 Overridden_Subp : Entity_Id;
145 Is_Primitive : Boolean);
146 -- Verify the consistency of an overriding_indicator given for subprogram
147 -- declaration, body, renaming, or instantiation. Overridden_Subp is set
148 -- if the scope where we are introducing the subprogram contains a
149 -- type-conformant subprogram that becomes hidden by the new subprogram.
150 -- Is_Primitive indicates whether the subprogram is primitive.
152 procedure Check_Subprogram_Order (N : Node_Id);
153 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
154 -- the alpha ordering rule for N if this ordering requirement applicable.
156 procedure Check_Returns
160 Proc : Entity_Id := Empty);
161 -- Called to check for missing return statements in a function body, or for
162 -- returns present in a procedure body which has No_Return set. HSS is the
163 -- handled statement sequence for the subprogram body. This procedure
164 -- checks all flow paths to make sure they either have return (Mode = 'F',
165 -- used for functions) or do not have a return (Mode = 'P', used for
166 -- No_Return procedures). The flag Err is set if there are any control
167 -- paths not explicitly terminated by a return in the function case, and is
168 -- True otherwise. Proc is the entity for the procedure case and is used
169 -- in posting the warning message.
171 procedure Enter_Overloaded_Entity (S : Entity_Id);
172 -- This procedure makes S, a new overloaded entity, into the first visible
173 -- entity with that name.
175 procedure Install_Entity (E : Entity_Id);
176 -- Make single entity visible. Used for generic formals as well
178 procedure Install_Formals (Id : Entity_Id);
179 -- On entry to a subprogram body, make the formals visible. Note that
180 -- simply placing the subprogram on the scope stack is not sufficient:
181 -- the formals must become the current entities for their names.
183 function Is_Non_Overriding_Operation
185 New_E : Entity_Id) return Boolean;
186 -- Enforce the rule given in 12.3(18): a private operation in an instance
187 -- overrides an inherited operation only if the corresponding operation
188 -- was overriding in the generic. This can happen for primitive operations
189 -- of types derived (in the generic unit) from formal private or formal
192 procedure Make_Inequality_Operator (S : Entity_Id);
193 -- Create the declaration for an inequality operator that is implicitly
194 -- created by a user-defined equality operator that yields a boolean.
196 procedure May_Need_Actuals (Fun : Entity_Id);
197 -- Flag functions that can be called without parameters, i.e. those that
198 -- have no parameters, or those for which defaults exist for all parameters
200 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id);
201 -- If there is a separate spec for a subprogram or generic subprogram, the
202 -- formals of the body are treated as references to the corresponding
203 -- formals of the spec. This reference does not count as an actual use of
204 -- the formal, in order to diagnose formals that are unused in the body.
206 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
207 -- Formal_Id is an formal parameter entity. This procedure deals with
208 -- setting the proper validity status for this entity, which depends
209 -- on the kind of parameter and the validity checking mode.
211 ------------------------------
212 -- Analyze_Return_Statement --
213 ------------------------------
215 procedure Analyze_Return_Statement (N : Node_Id) is
217 pragma Assert (Nkind (N) = N_Simple_Return_Statement
219 Nkind (N) = N_Extended_Return_Statement);
221 Returns_Object : constant Boolean :=
222 Nkind (N) = N_Extended_Return_Statement
224 (Nkind (N) = N_Simple_Return_Statement
225 and then Present (Expression (N)));
226 -- True if we're returning something; that is, "return <expression>;"
227 -- or "return Result : T [:= ...]". False for "return;". Used for error
228 -- checking: If Returns_Object is True, N should apply to a function
229 -- body; otherwise N should apply to a procedure body, entry body,
230 -- accept statement, or extended return statement.
232 function Find_What_It_Applies_To return Entity_Id;
233 -- Find the entity representing the innermost enclosing body, accept
234 -- statement, or extended return statement. If the result is a callable
235 -- construct or extended return statement, then this will be the value
236 -- of the Return_Applies_To attribute. Otherwise, the program is
237 -- illegal. See RM-6.5(4/2).
239 -----------------------------
240 -- Find_What_It_Applies_To --
241 -----------------------------
243 function Find_What_It_Applies_To return Entity_Id is
244 Result : Entity_Id := Empty;
247 -- Loop outward through the Scope_Stack, skipping blocks and loops
249 for J in reverse 0 .. Scope_Stack.Last loop
250 Result := Scope_Stack.Table (J).Entity;
251 exit when Ekind (Result) /= E_Block and then
252 Ekind (Result) /= E_Loop;
255 pragma Assert (Present (Result));
257 end Find_What_It_Applies_To;
259 -- Local declarations
261 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
262 Kind : constant Entity_Kind := Ekind (Scope_Id);
263 Loc : constant Source_Ptr := Sloc (N);
264 Stm_Entity : constant Entity_Id :=
266 (E_Return_Statement, Current_Scope, Loc, 'R');
268 -- Start of processing for Analyze_Return_Statement
271 Set_Return_Statement_Entity (N, Stm_Entity);
273 Set_Etype (Stm_Entity, Standard_Void_Type);
274 Set_Return_Applies_To (Stm_Entity, Scope_Id);
276 -- Place Return entity on scope stack, to simplify enforcement of 6.5
277 -- (4/2): an inner return statement will apply to this extended return.
279 if Nkind (N) = N_Extended_Return_Statement then
280 Push_Scope (Stm_Entity);
283 -- Check that pragma No_Return is obeyed
285 if No_Return (Scope_Id) then
286 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
289 -- Warn on any unassigned OUT parameters if in procedure
291 if Ekind (Scope_Id) = E_Procedure then
292 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
295 -- Check that functions return objects, and other things do not
297 if Kind = E_Function or else Kind = E_Generic_Function then
298 if not Returns_Object then
299 Error_Msg_N ("missing expression in return from function", N);
302 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
303 if Returns_Object then
304 Error_Msg_N ("procedure cannot return value (use function)", N);
307 elsif Kind = E_Entry or else Kind = E_Entry_Family then
308 if Returns_Object then
309 if Is_Protected_Type (Scope (Scope_Id)) then
310 Error_Msg_N ("entry body cannot return value", N);
312 Error_Msg_N ("accept statement cannot return value", N);
316 elsif Kind = E_Return_Statement then
318 -- We are nested within another return statement, which must be an
319 -- extended_return_statement.
321 if Returns_Object then
323 ("extended_return_statement cannot return value; " &
324 "use `""RETURN;""`", N);
328 Error_Msg_N ("illegal context for return statement", N);
331 if Kind = E_Function or else Kind = E_Generic_Function then
332 Analyze_Function_Return (N);
335 if Nkind (N) = N_Extended_Return_Statement then
339 Check_Unreachable_Code (N);
340 end Analyze_Return_Statement;
342 ---------------------------------------------
343 -- Analyze_Abstract_Subprogram_Declaration --
344 ---------------------------------------------
346 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
347 Designator : constant Entity_Id :=
348 Analyze_Subprogram_Specification (Specification (N));
349 Scop : constant Entity_Id := Current_Scope;
352 Generate_Definition (Designator);
353 Set_Is_Abstract_Subprogram (Designator);
354 New_Overloaded_Entity (Designator);
355 Check_Delayed_Subprogram (Designator);
357 Set_Categorization_From_Scope (Designator, Scop);
359 if Ekind (Scope (Designator)) = E_Protected_Type then
361 ("abstract subprogram not allowed in protected type", N);
363 -- Issue a warning if the abstract subprogram is neither a dispatching
364 -- operation nor an operation that overrides an inherited subprogram or
365 -- predefined operator, since this most likely indicates a mistake.
367 elsif Warn_On_Redundant_Constructs
368 and then not Is_Dispatching_Operation (Designator)
369 and then not Is_Overriding_Operation (Designator)
370 and then (not Is_Operator_Symbol_Name (Chars (Designator))
371 or else Scop /= Scope (Etype (First_Formal (Designator))))
374 ("?abstract subprogram is not dispatching or overriding", N);
377 Generate_Reference_To_Formals (Designator);
378 end Analyze_Abstract_Subprogram_Declaration;
380 ----------------------------------------
381 -- Analyze_Extended_Return_Statement --
382 ----------------------------------------
384 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
386 Analyze_Return_Statement (N);
387 end Analyze_Extended_Return_Statement;
389 ----------------------------
390 -- Analyze_Function_Call --
391 ----------------------------
393 procedure Analyze_Function_Call (N : Node_Id) is
394 P : constant Node_Id := Name (N);
395 L : constant List_Id := Parameter_Associations (N);
401 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
402 -- as B (A, X). If the rewriting is successful, the call has been
403 -- analyzed and we just return.
405 if Nkind (P) = N_Selected_Component
406 and then Name (N) /= P
407 and then Is_Rewrite_Substitution (N)
408 and then Present (Etype (N))
413 -- If error analyzing name, then set Any_Type as result type and return
415 if Etype (P) = Any_Type then
416 Set_Etype (N, Any_Type);
420 -- Otherwise analyze the parameters
424 while Present (Actual) loop
426 Check_Parameterless_Call (Actual);
432 end Analyze_Function_Call;
434 -----------------------------
435 -- Analyze_Function_Return --
436 -----------------------------
438 procedure Analyze_Function_Return (N : Node_Id) is
439 Loc : constant Source_Ptr := Sloc (N);
440 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
441 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
443 R_Type : constant Entity_Id := Etype (Scope_Id);
444 -- Function result subtype
446 procedure Check_Limited_Return (Expr : Node_Id);
447 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
448 -- limited types. Used only for simple return statements.
449 -- Expr is the expression returned.
451 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
452 -- Check that the return_subtype_indication properly matches the result
453 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
455 --------------------------
456 -- Check_Limited_Return --
457 --------------------------
459 procedure Check_Limited_Return (Expr : Node_Id) is
461 -- Ada 2005 (AI-318-02): Return-by-reference types have been
462 -- removed and replaced by anonymous access results. This is an
463 -- incompatibility with Ada 95. Not clear whether this should be
464 -- enforced yet or perhaps controllable with special switch. ???
466 if Is_Limited_Type (R_Type)
467 and then Comes_From_Source (N)
468 and then not In_Instance_Body
469 and then not OK_For_Limited_Init_In_05 (Expr)
473 if Ada_Version >= Ada_05
474 and then not Debug_Flag_Dot_L
475 and then not GNAT_Mode
478 ("(Ada 2005) cannot copy object of a limited type " &
479 "(RM-2005 6.5(5.5/2))", Expr);
480 if Is_Inherently_Limited_Type (R_Type) then
482 ("\return by reference not permitted in Ada 2005", Expr);
485 -- Warn in Ada 95 mode, to give folks a heads up about this
488 -- In GNAT mode, this is just a warning, to allow it to be
489 -- evilly turned off. Otherwise it is a real error.
491 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
492 if Is_Inherently_Limited_Type (R_Type) then
494 ("return by reference not permitted in Ada 2005 " &
495 "(RM-2005 6.5(5.5/2))?", Expr);
498 ("cannot copy object of a limited type in Ada 2005 " &
499 "(RM-2005 6.5(5.5/2))?", Expr);
502 -- Ada 95 mode, compatibility warnings disabled
505 return; -- skip continuation messages below
509 ("\consider switching to return of access type", Expr);
510 Explain_Limited_Type (R_Type, Expr);
512 end Check_Limited_Return;
514 -------------------------------------
515 -- Check_Return_Subtype_Indication --
516 -------------------------------------
518 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
519 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
520 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
521 -- Subtype given in the extended return statement;
522 -- this must match R_Type.
524 Subtype_Ind : constant Node_Id :=
525 Object_Definition (Original_Node (Obj_Decl));
527 R_Type_Is_Anon_Access :
529 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
531 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
533 Ekind (R_Type) = E_Anonymous_Access_Type;
534 -- True if return type of the function is an anonymous access type
535 -- Can't we make Is_Anonymous_Access_Type in einfo ???
537 R_Stm_Type_Is_Anon_Access :
539 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
541 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
543 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
544 -- True if type of the return object is an anonymous access type
547 -- First, avoid cascade errors:
549 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
553 -- "return access T" case; check that the return statement also has
554 -- "access T", and that the subtypes statically match:
556 if R_Type_Is_Anon_Access then
557 if R_Stm_Type_Is_Anon_Access then
558 if Base_Type (Designated_Type (R_Stm_Type)) /=
559 Base_Type (Designated_Type (R_Type))
560 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
563 ("subtype must statically match function result subtype",
564 Subtype_Mark (Subtype_Ind));
568 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
571 -- Subtype_indication case; check that the types are the same, and
572 -- statically match if appropriate:
574 elsif Base_Type (R_Stm_Type) = Base_Type (R_Type) then
575 if Is_Constrained (R_Type) then
576 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
578 ("subtype must statically match function result subtype",
583 -- If the function's result type doesn't match the return object
584 -- entity's type, then we check for the case where the result type
585 -- is class-wide, and allow the declaration if the type of the object
586 -- definition matches the class-wide type. This prevents rejection
587 -- in the case where the object declaration is initialized by a call
588 -- to a build-in-place function with a specific result type and the
589 -- object entity had its type changed to that specific type. (Note
590 -- that the ARG believes that return objects should be allowed to
591 -- have a type covered by a class-wide result type in any case, so
592 -- once that relaxation is made (see AI05-32), the above check for
593 -- type compatibility should be changed to test Covers rather than
594 -- equality, and then the following special test will no longer be
597 elsif Is_Class_Wide_Type (R_Type)
599 R_Type = Etype (Object_Definition (Original_Node (Obj_Decl)))
605 ("wrong type for return_subtype_indication", Subtype_Ind);
607 end Check_Return_Subtype_Indication;
609 ---------------------
610 -- Local Variables --
611 ---------------------
615 -- Start of processing for Analyze_Function_Return
618 Set_Return_Present (Scope_Id);
620 if Nkind (N) = N_Simple_Return_Statement then
621 Expr := Expression (N);
622 Analyze_And_Resolve (Expr, R_Type);
623 Check_Limited_Return (Expr);
626 -- Analyze parts specific to extended_return_statement:
629 Obj_Decl : constant Node_Id :=
630 Last (Return_Object_Declarations (N));
632 HSS : constant Node_Id := Handled_Statement_Sequence (N);
635 Expr := Expression (Obj_Decl);
637 -- Note: The check for OK_For_Limited_Init will happen in
638 -- Analyze_Object_Declaration; we treat it as a normal
639 -- object declaration.
643 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
644 Check_Return_Subtype_Indication (Obj_Decl);
646 if Present (HSS) then
649 if Present (Exception_Handlers (HSS)) then
651 -- ???Has_Nested_Block_With_Handler needs to be set.
652 -- Probably by creating an actual N_Block_Statement.
653 -- Probably in Expand.
659 Check_References (Stm_Entity);
663 -- Case of Expr present (Etype check defends against previous errors)
666 and then Present (Etype (Expr))
668 -- Apply constraint check. Note that this is done before the implicit
669 -- conversion of the expression done for anonymous access types to
670 -- ensure correct generation of the null-excluding check asssociated
671 -- with null-excluding expressions found in return statements.
673 Apply_Constraint_Check (Expr, R_Type);
675 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
676 -- type, apply an implicit conversion of the expression to that type
677 -- to force appropriate static and run-time accessibility checks.
679 if Ada_Version >= Ada_05
680 and then Ekind (R_Type) = E_Anonymous_Access_Type
682 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
683 Analyze_And_Resolve (Expr, R_Type);
686 if (Is_Class_Wide_Type (Etype (Expr))
687 or else Is_Dynamically_Tagged (Expr))
688 and then not Is_Class_Wide_Type (R_Type)
691 ("dynamically tagged expression not allowed!", Expr);
694 -- ??? A real run-time accessibility check is needed in cases
695 -- involving dereferences of access parameters. For now we just
696 -- check the static cases.
698 if (Ada_Version < Ada_05 or else Debug_Flag_Dot_L)
699 and then Is_Inherently_Limited_Type (Etype (Scope_Id))
700 and then Object_Access_Level (Expr) >
701 Subprogram_Access_Level (Scope_Id)
704 Make_Raise_Program_Error (Loc,
705 Reason => PE_Accessibility_Check_Failed));
709 ("cannot return a local value by reference?", N);
711 ("\& will be raised at run time?",
712 N, Standard_Program_Error);
716 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
717 and then Null_Exclusion_Present (Parent (Scope_Id))
719 Apply_Compile_Time_Constraint_Error
721 Msg => "(Ada 2005) null not allowed for "
722 & "null-excluding return?",
723 Reason => CE_Null_Not_Allowed);
726 end Analyze_Function_Return;
728 -------------------------------------
729 -- Analyze_Generic_Subprogram_Body --
730 -------------------------------------
732 procedure Analyze_Generic_Subprogram_Body
736 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
737 Kind : constant Entity_Kind := Ekind (Gen_Id);
743 -- Copy body and disable expansion while analyzing the generic For a
744 -- stub, do not copy the stub (which would load the proper body), this
745 -- will be done when the proper body is analyzed.
747 if Nkind (N) /= N_Subprogram_Body_Stub then
748 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
753 Spec := Specification (N);
755 -- Within the body of the generic, the subprogram is callable, and
756 -- behaves like the corresponding non-generic unit.
758 Body_Id := Defining_Entity (Spec);
760 if Kind = E_Generic_Procedure
761 and then Nkind (Spec) /= N_Procedure_Specification
763 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
766 elsif Kind = E_Generic_Function
767 and then Nkind (Spec) /= N_Function_Specification
769 Error_Msg_N ("invalid body for generic function ", Body_Id);
773 Set_Corresponding_Body (Gen_Decl, Body_Id);
775 if Has_Completion (Gen_Id)
776 and then Nkind (Parent (N)) /= N_Subunit
778 Error_Msg_N ("duplicate generic body", N);
781 Set_Has_Completion (Gen_Id);
784 if Nkind (N) = N_Subprogram_Body_Stub then
785 Set_Ekind (Defining_Entity (Specification (N)), Kind);
787 Set_Corresponding_Spec (N, Gen_Id);
790 if Nkind (Parent (N)) = N_Compilation_Unit then
791 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
794 -- Make generic parameters immediately visible in the body. They are
795 -- needed to process the formals declarations. Then make the formals
796 -- visible in a separate step.
802 First_Ent : Entity_Id;
805 First_Ent := First_Entity (Gen_Id);
808 while Present (E) and then not Is_Formal (E) loop
813 Set_Use (Generic_Formal_Declarations (Gen_Decl));
815 -- Now generic formals are visible, and the specification can be
816 -- analyzed, for subsequent conformance check.
818 Body_Id := Analyze_Subprogram_Specification (Spec);
820 -- Make formal parameters visible
824 -- E is the first formal parameter, we loop through the formals
825 -- installing them so that they will be visible.
827 Set_First_Entity (Gen_Id, E);
828 while Present (E) loop
834 -- Visible generic entity is callable within its own body
836 Set_Ekind (Gen_Id, Ekind (Body_Id));
837 Set_Ekind (Body_Id, E_Subprogram_Body);
838 Set_Convention (Body_Id, Convention (Gen_Id));
839 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
840 Set_Scope (Body_Id, Scope (Gen_Id));
841 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
843 if Nkind (N) = N_Subprogram_Body_Stub then
845 -- No body to analyze, so restore state of generic unit
847 Set_Ekind (Gen_Id, Kind);
848 Set_Ekind (Body_Id, Kind);
850 if Present (First_Ent) then
851 Set_First_Entity (Gen_Id, First_Ent);
858 -- If this is a compilation unit, it must be made visible explicitly,
859 -- because the compilation of the declaration, unlike other library
860 -- unit declarations, does not. If it is not a unit, the following
861 -- is redundant but harmless.
863 Set_Is_Immediately_Visible (Gen_Id);
864 Reference_Body_Formals (Gen_Id, Body_Id);
866 if Is_Child_Unit (Gen_Id) then
867 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
870 Set_Actual_Subtypes (N, Current_Scope);
871 Analyze_Declarations (Declarations (N));
873 Analyze (Handled_Statement_Sequence (N));
875 Save_Global_References (Original_Node (N));
877 -- Prior to exiting the scope, include generic formals again (if any
878 -- are present) in the set of local entities.
880 if Present (First_Ent) then
881 Set_First_Entity (Gen_Id, First_Ent);
884 Check_References (Gen_Id);
887 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
889 Check_Subprogram_Order (N);
891 -- Outside of its body, unit is generic again
893 Set_Ekind (Gen_Id, Kind);
894 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
897 Style.Check_Identifier (Body_Id, Gen_Id);
900 end Analyze_Generic_Subprogram_Body;
902 -----------------------------
903 -- Analyze_Operator_Symbol --
904 -----------------------------
906 -- An operator symbol such as "+" or "and" may appear in context where the
907 -- literal denotes an entity name, such as "+"(x, y) or in context when it
908 -- is just a string, as in (conjunction = "or"). In these cases the parser
909 -- generates this node, and the semantics does the disambiguation. Other
910 -- such case are actuals in an instantiation, the generic unit in an
911 -- instantiation, and pragma arguments.
913 procedure Analyze_Operator_Symbol (N : Node_Id) is
914 Par : constant Node_Id := Parent (N);
917 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
918 or else Nkind (Par) = N_Function_Instantiation
919 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
920 or else (Nkind (Par) = N_Pragma_Argument_Association
921 and then not Is_Pragma_String_Literal (Par))
922 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
923 or else (Nkind (Par) = N_Attribute_Reference
924 and then Attribute_Name (Par) /= Name_Value)
926 Find_Direct_Name (N);
929 Change_Operator_Symbol_To_String_Literal (N);
932 end Analyze_Operator_Symbol;
934 -----------------------------------
935 -- Analyze_Parameter_Association --
936 -----------------------------------
938 procedure Analyze_Parameter_Association (N : Node_Id) is
940 Analyze (Explicit_Actual_Parameter (N));
941 end Analyze_Parameter_Association;
943 ----------------------------
944 -- Analyze_Procedure_Call --
945 ----------------------------
947 procedure Analyze_Procedure_Call (N : Node_Id) is
948 Loc : constant Source_Ptr := Sloc (N);
949 P : constant Node_Id := Name (N);
950 Actuals : constant List_Id := Parameter_Associations (N);
954 procedure Analyze_Call_And_Resolve;
955 -- Do Analyze and Resolve calls for procedure call
957 ------------------------------
958 -- Analyze_Call_And_Resolve --
959 ------------------------------
961 procedure Analyze_Call_And_Resolve is
963 if Nkind (N) = N_Procedure_Call_Statement then
965 Resolve (N, Standard_Void_Type);
969 end Analyze_Call_And_Resolve;
971 -- Start of processing for Analyze_Procedure_Call
974 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
975 -- a procedure call or an entry call. The prefix may denote an access
976 -- to subprogram type, in which case an implicit dereference applies.
977 -- If the prefix is an indexed component (without implicit defererence)
978 -- then the construct denotes a call to a member of an entire family.
979 -- If the prefix is a simple name, it may still denote a call to a
980 -- parameterless member of an entry family. Resolution of these various
981 -- interpretations is delicate.
985 -- If this is a call of the form Obj.Op, the call may have been
986 -- analyzed and possibly rewritten into a block, in which case
993 -- If error analyzing prefix, then set Any_Type as result and return
995 if Etype (P) = Any_Type then
996 Set_Etype (N, Any_Type);
1000 -- Otherwise analyze the parameters
1002 if Present (Actuals) then
1003 Actual := First (Actuals);
1005 while Present (Actual) loop
1007 Check_Parameterless_Call (Actual);
1012 -- Special processing for Elab_Spec and Elab_Body calls
1014 if Nkind (P) = N_Attribute_Reference
1015 and then (Attribute_Name (P) = Name_Elab_Spec
1016 or else Attribute_Name (P) = Name_Elab_Body)
1018 if Present (Actuals) then
1020 ("no parameters allowed for this call", First (Actuals));
1024 Set_Etype (N, Standard_Void_Type);
1027 elsif Is_Entity_Name (P)
1028 and then Is_Record_Type (Etype (Entity (P)))
1029 and then Remote_AST_I_Dereference (P)
1033 elsif Is_Entity_Name (P)
1034 and then Ekind (Entity (P)) /= E_Entry_Family
1036 if Is_Access_Type (Etype (P))
1037 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1038 and then No (Actuals)
1039 and then Comes_From_Source (N)
1041 Error_Msg_N ("missing explicit dereference in call", N);
1044 Analyze_Call_And_Resolve;
1046 -- If the prefix is the simple name of an entry family, this is
1047 -- a parameterless call from within the task body itself.
1049 elsif Is_Entity_Name (P)
1050 and then Nkind (P) = N_Identifier
1051 and then Ekind (Entity (P)) = E_Entry_Family
1052 and then Present (Actuals)
1053 and then No (Next (First (Actuals)))
1055 -- Can be call to parameterless entry family. What appears to be the
1056 -- sole argument is in fact the entry index. Rewrite prefix of node
1057 -- accordingly. Source representation is unchanged by this
1061 Make_Indexed_Component (Loc,
1063 Make_Selected_Component (Loc,
1064 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1065 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1066 Expressions => Actuals);
1067 Set_Name (N, New_N);
1068 Set_Etype (New_N, Standard_Void_Type);
1069 Set_Parameter_Associations (N, No_List);
1070 Analyze_Call_And_Resolve;
1072 elsif Nkind (P) = N_Explicit_Dereference then
1073 if Ekind (Etype (P)) = E_Subprogram_Type then
1074 Analyze_Call_And_Resolve;
1076 Error_Msg_N ("expect access to procedure in call", P);
1079 -- The name can be a selected component or an indexed component that
1080 -- yields an access to subprogram. Such a prefix is legal if the call
1081 -- has parameter associations.
1083 elsif Is_Access_Type (Etype (P))
1084 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1086 if Present (Actuals) then
1087 Analyze_Call_And_Resolve;
1089 Error_Msg_N ("missing explicit dereference in call ", N);
1092 -- If not an access to subprogram, then the prefix must resolve to the
1093 -- name of an entry, entry family, or protected operation.
1095 -- For the case of a simple entry call, P is a selected component where
1096 -- the prefix is the task and the selector name is the entry. A call to
1097 -- a protected procedure will have the same syntax. If the protected
1098 -- object contains overloaded operations, the entity may appear as a
1099 -- function, the context will select the operation whose type is Void.
1101 elsif Nkind (P) = N_Selected_Component
1102 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1104 Ekind (Entity (Selector_Name (P))) = E_Procedure
1106 Ekind (Entity (Selector_Name (P))) = E_Function)
1108 Analyze_Call_And_Resolve;
1110 elsif Nkind (P) = N_Selected_Component
1111 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1112 and then Present (Actuals)
1113 and then No (Next (First (Actuals)))
1115 -- Can be call to parameterless entry family. What appears to be the
1116 -- sole argument is in fact the entry index. Rewrite prefix of node
1117 -- accordingly. Source representation is unchanged by this
1121 Make_Indexed_Component (Loc,
1122 Prefix => New_Copy (P),
1123 Expressions => Actuals);
1124 Set_Name (N, New_N);
1125 Set_Etype (New_N, Standard_Void_Type);
1126 Set_Parameter_Associations (N, No_List);
1127 Analyze_Call_And_Resolve;
1129 -- For the case of a reference to an element of an entry family, P is
1130 -- an indexed component whose prefix is a selected component (task and
1131 -- entry family), and whose index is the entry family index.
1133 elsif Nkind (P) = N_Indexed_Component
1134 and then Nkind (Prefix (P)) = N_Selected_Component
1135 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1137 Analyze_Call_And_Resolve;
1139 -- If the prefix is the name of an entry family, it is a call from
1140 -- within the task body itself.
1142 elsif Nkind (P) = N_Indexed_Component
1143 and then Nkind (Prefix (P)) = N_Identifier
1144 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1147 Make_Selected_Component (Loc,
1148 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1149 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1150 Rewrite (Prefix (P), New_N);
1152 Analyze_Call_And_Resolve;
1154 -- Anything else is an error
1157 Error_Msg_N ("invalid procedure or entry call", N);
1159 end Analyze_Procedure_Call;
1161 -------------------------------------
1162 -- Analyze_Simple_Return_Statement --
1163 -------------------------------------
1165 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1167 if Present (Expression (N)) then
1168 Mark_Coextensions (N, Expression (N));
1171 Analyze_Return_Statement (N);
1172 end Analyze_Simple_Return_Statement;
1174 -------------------------
1175 -- Analyze_Return_Type --
1176 -------------------------
1178 procedure Analyze_Return_Type (N : Node_Id) is
1179 Designator : constant Entity_Id := Defining_Entity (N);
1180 Typ : Entity_Id := Empty;
1183 -- Normal case where result definition does not indicate an error
1185 if Result_Definition (N) /= Error then
1186 if Nkind (Result_Definition (N)) = N_Access_Definition then
1187 Typ := Access_Definition (N, Result_Definition (N));
1188 Set_Parent (Typ, Result_Definition (N));
1189 Set_Is_Local_Anonymous_Access (Typ);
1190 Set_Etype (Designator, Typ);
1192 -- Subtype_Mark case
1195 Find_Type (Result_Definition (N));
1196 Typ := Entity (Result_Definition (N));
1197 Set_Etype (Designator, Typ);
1199 if Ekind (Typ) = E_Incomplete_Type
1200 and then Is_Value_Type (Typ)
1204 elsif Ekind (Typ) = E_Incomplete_Type
1205 or else (Is_Class_Wide_Type (Typ)
1207 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1210 ("invalid use of incomplete type", Result_Definition (N));
1214 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1216 Null_Exclusion_Static_Checks (N);
1218 -- Case where result definition does indicate an error
1221 Set_Etype (Designator, Any_Type);
1223 end Analyze_Return_Type;
1225 -----------------------------
1226 -- Analyze_Subprogram_Body --
1227 -----------------------------
1229 -- This procedure is called for regular subprogram bodies, generic bodies,
1230 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1231 -- specification matters, and is used to create a proper declaration for
1232 -- the subprogram, or to perform conformance checks.
1234 procedure Analyze_Subprogram_Body (N : Node_Id) is
1235 Loc : constant Source_Ptr := Sloc (N);
1236 Body_Spec : constant Node_Id := Specification (N);
1237 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1238 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1239 Body_Deleted : constant Boolean := False;
1242 Spec_Id : Entity_Id;
1243 Spec_Decl : Node_Id := Empty;
1244 Last_Formal : Entity_Id := Empty;
1245 Conformant : Boolean;
1246 Missing_Ret : Boolean;
1249 procedure Check_Anonymous_Return;
1250 -- (Ada 2005): if a function returns an access type that denotes a task,
1251 -- or a type that contains tasks, we must create a master entity for
1252 -- the anonymous type, which typically will be used in an allocator
1253 -- in the body of the function.
1255 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1256 -- Look ahead to recognize a pragma that may appear after the body.
1257 -- If there is a previous spec, check that it appears in the same
1258 -- declarative part. If the pragma is Inline_Always, perform inlining
1259 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1260 -- If the body acts as a spec, and inlining is required, we create a
1261 -- subprogram declaration for it, in order to attach the body to inline.
1263 procedure Copy_Parameter_List (Plist : List_Id);
1264 -- Utility to create a parameter profile for a new subprogram spec,
1265 -- when the subprogram has a body that acts as spec. This is done for
1266 -- some cases of inlining, and for private protected ops.
1268 procedure Verify_Overriding_Indicator;
1269 -- If there was a previous spec, the entity has been entered in the
1270 -- current scope previously. If the body itself carries an overriding
1271 -- indicator, check that it is consistent with the known status of the
1274 ----------------------------
1275 -- Check_Anonymous_Return --
1276 ----------------------------
1278 procedure Check_Anonymous_Return is
1283 if Present (Spec_Id) then
1289 if Ekind (Scop) = E_Function
1290 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1291 and then Has_Task (Designated_Type (Etype (Scop)))
1292 and then Expander_Active
1295 Make_Object_Declaration (Loc,
1296 Defining_Identifier =>
1297 Make_Defining_Identifier (Loc, Name_uMaster),
1298 Constant_Present => True,
1299 Object_Definition =>
1300 New_Reference_To (RTE (RE_Master_Id), Loc),
1302 Make_Explicit_Dereference (Loc,
1303 New_Reference_To (RTE (RE_Current_Master), Loc)));
1305 if Present (Declarations (N)) then
1306 Prepend (Decl, Declarations (N));
1308 Set_Declarations (N, New_List (Decl));
1311 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1312 Set_Has_Master_Entity (Scop);
1314 end Check_Anonymous_Return;
1316 -------------------------
1317 -- Check_Inline_Pragma --
1318 -------------------------
1320 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1325 if not Expander_Active then
1329 if Is_List_Member (N)
1330 and then Present (Next (N))
1331 and then Nkind (Next (N)) = N_Pragma
1335 if Nkind (Prag) = N_Pragma
1337 (Get_Pragma_Id (Chars (Prag)) = Pragma_Inline_Always
1340 and then Get_Pragma_Id (Chars (Prag)) = Pragma_Inline))
1343 (Expression (First (Pragma_Argument_Associations (Prag))))
1354 if Present (Prag) then
1355 if Present (Spec_Id) then
1356 if List_Containing (N) =
1357 List_Containing (Unit_Declaration_Node (Spec_Id))
1363 -- Create a subprogram declaration, to make treatment uniform
1366 Subp : constant Entity_Id :=
1367 Make_Defining_Identifier (Loc, Chars (Body_Id));
1368 Decl : constant Node_Id :=
1369 Make_Subprogram_Declaration (Loc,
1370 Specification => New_Copy_Tree (Specification (N)));
1372 Set_Defining_Unit_Name (Specification (Decl), Subp);
1374 if Present (First_Formal (Body_Id)) then
1376 Copy_Parameter_List (Plist);
1377 Set_Parameter_Specifications
1378 (Specification (Decl), Plist);
1381 Insert_Before (N, Decl);
1384 Set_Has_Pragma_Inline (Subp);
1386 if Get_Pragma_Id (Chars (Prag)) = Pragma_Inline_Always then
1387 Set_Is_Inlined (Subp);
1388 Set_Next_Rep_Item (Prag, First_Rep_Item (Subp));
1389 Set_First_Rep_Item (Subp, Prag);
1396 end Check_Inline_Pragma;
1398 -------------------------
1399 -- Copy_Parameter_List --
1400 -------------------------
1402 procedure Copy_Parameter_List (Plist : List_Id) is
1406 Formal := First_Formal (Body_Id);
1408 while Present (Formal) loop
1410 (Make_Parameter_Specification (Loc,
1411 Defining_Identifier =>
1412 Make_Defining_Identifier (Sloc (Formal),
1413 Chars => Chars (Formal)),
1414 In_Present => In_Present (Parent (Formal)),
1415 Out_Present => Out_Present (Parent (Formal)),
1417 New_Reference_To (Etype (Formal), Loc),
1419 New_Copy_Tree (Expression (Parent (Formal)))),
1422 Next_Formal (Formal);
1424 end Copy_Parameter_List;
1426 ---------------------------------
1427 -- Verify_Overriding_Indicator --
1428 ---------------------------------
1430 procedure Verify_Overriding_Indicator is
1432 if Must_Override (Body_Spec)
1433 and then not Is_Overriding_Operation (Spec_Id)
1436 ("subprogram& is not overriding", Body_Spec, Spec_Id);
1438 elsif Must_Not_Override (Body_Spec) then
1439 if Is_Overriding_Operation (Spec_Id) then
1441 ("subprogram& overrides inherited operation",
1442 Body_Spec, Spec_Id);
1444 -- If this is not a primitive operation the overriding indicator
1445 -- is altogether illegal.
1447 elsif not Is_Primitive (Spec_Id) then
1448 Error_Msg_N ("overriding indicator only allowed " &
1449 "if subprogram is primitive",
1453 end Verify_Overriding_Indicator;
1455 -- Start of processing for Analyze_Subprogram_Body
1458 if Debug_Flag_C then
1459 Write_Str ("==== Compiling subprogram body ");
1460 Write_Name (Chars (Body_Id));
1461 Write_Str (" from ");
1462 Write_Location (Loc);
1466 Trace_Scope (N, Body_Id, " Analyze subprogram");
1468 -- Generic subprograms are handled separately. They always have a
1469 -- generic specification. Determine whether current scope has a
1470 -- previous declaration.
1472 -- If the subprogram body is defined within an instance of the same
1473 -- name, the instance appears as a package renaming, and will be hidden
1474 -- within the subprogram.
1476 if Present (Prev_Id)
1477 and then not Is_Overloadable (Prev_Id)
1478 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
1479 or else Comes_From_Source (Prev_Id))
1481 if Is_Generic_Subprogram (Prev_Id) then
1483 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1484 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1486 Analyze_Generic_Subprogram_Body (N, Spec_Id);
1490 -- Previous entity conflicts with subprogram name. Attempting to
1491 -- enter name will post error.
1493 Enter_Name (Body_Id);
1497 -- Non-generic case, find the subprogram declaration, if one was seen,
1498 -- or enter new overloaded entity in the current scope. If the
1499 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
1500 -- part of the context of one of its subunits. No need to redo the
1503 elsif Prev_Id = Body_Id
1504 and then Has_Completion (Body_Id)
1509 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
1511 if Nkind (N) = N_Subprogram_Body_Stub
1512 or else No (Corresponding_Spec (N))
1514 Spec_Id := Find_Corresponding_Spec (N);
1516 -- If this is a duplicate body, no point in analyzing it
1518 if Error_Posted (N) then
1522 -- A subprogram body should cause freezing of its own declaration,
1523 -- but if there was no previous explicit declaration, then the
1524 -- subprogram will get frozen too late (there may be code within
1525 -- the body that depends on the subprogram having been frozen,
1526 -- such as uses of extra formals), so we force it to be frozen
1527 -- here. Same holds if the body and the spec are compilation
1530 if No (Spec_Id) then
1531 Freeze_Before (N, Body_Id);
1533 elsif Nkind (Parent (N)) = N_Compilation_Unit then
1534 Freeze_Before (N, Spec_Id);
1537 Spec_Id := Corresponding_Spec (N);
1541 -- Do not inline any subprogram that contains nested subprograms, since
1542 -- the backend inlining circuit seems to generate uninitialized
1543 -- references in this case. We know this happens in the case of front
1544 -- end ZCX support, but it also appears it can happen in other cases as
1545 -- well. The backend often rejects attempts to inline in the case of
1546 -- nested procedures anyway, so little if anything is lost by this.
1547 -- Note that this is test is for the benefit of the back-end. There is
1548 -- a separate test for front-end inlining that also rejects nested
1551 -- Do not do this test if errors have been detected, because in some
1552 -- error cases, this code blows up, and we don't need it anyway if
1553 -- there have been errors, since we won't get to the linker anyway.
1555 if Comes_From_Source (Body_Id)
1556 and then Serious_Errors_Detected = 0
1560 P_Ent := Scope (P_Ent);
1561 exit when No (P_Ent) or else P_Ent = Standard_Standard;
1563 if Is_Subprogram (P_Ent) then
1564 Set_Is_Inlined (P_Ent, False);
1566 if Comes_From_Source (P_Ent)
1567 and then Has_Pragma_Inline (P_Ent)
1570 ("cannot inline& (nested subprogram)?",
1577 Check_Inline_Pragma (Spec_Id);
1579 -- Case of fully private operation in the body of the protected type.
1580 -- We must create a declaration for the subprogram, in order to attach
1581 -- the protected subprogram that will be used in internal calls.
1584 and then Comes_From_Source (N)
1585 and then Is_Protected_Type (Current_Scope)
1594 Formal := First_Formal (Body_Id);
1596 -- The protected operation always has at least one formal, namely
1597 -- the object itself, but it is only placed in the parameter list
1598 -- if expansion is enabled.
1601 or else Expander_Active
1609 Copy_Parameter_List (Plist);
1611 if Nkind (Body_Spec) = N_Procedure_Specification then
1613 Make_Procedure_Specification (Loc,
1614 Defining_Unit_Name =>
1615 Make_Defining_Identifier (Sloc (Body_Id),
1616 Chars => Chars (Body_Id)),
1617 Parameter_Specifications => Plist);
1620 Make_Function_Specification (Loc,
1621 Defining_Unit_Name =>
1622 Make_Defining_Identifier (Sloc (Body_Id),
1623 Chars => Chars (Body_Id)),
1624 Parameter_Specifications => Plist,
1625 Result_Definition =>
1626 New_Occurrence_Of (Etype (Body_Id), Loc));
1630 Make_Subprogram_Declaration (Loc,
1631 Specification => New_Spec);
1632 Insert_Before (N, Decl);
1633 Spec_Id := Defining_Unit_Name (New_Spec);
1635 -- Indicate that the entity comes from source, to ensure that
1636 -- cross-reference information is properly generated. The body
1637 -- itself is rewritten during expansion, and the body entity will
1638 -- not appear in calls to the operation.
1640 Set_Comes_From_Source (Spec_Id, True);
1642 Set_Has_Completion (Spec_Id);
1643 Set_Convention (Spec_Id, Convention_Protected);
1646 elsif Present (Spec_Id) then
1647 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1648 Verify_Overriding_Indicator;
1650 -- In general, the spec will be frozen when we start analyzing the
1651 -- body. However, for internally generated operations, such as
1652 -- wrapper functions for inherited operations with controlling
1653 -- results, the spec may not have been frozen by the time we
1654 -- expand the freeze actions that include the bodies. In particular,
1655 -- extra formals for accessibility or for return-in-place may need
1656 -- to be generated. Freeze nodes, if any, are inserted before the
1659 if not Is_Frozen (Spec_Id)
1660 and then Expander_Active
1662 -- Force the generation of its freezing node to ensure proper
1663 -- management of access types in the backend.
1665 -- This is definitely needed for some cases, but it is not clear
1666 -- why, to be investigated further???
1668 Set_Has_Delayed_Freeze (Spec_Id);
1669 Insert_Actions (N, Freeze_Entity (Spec_Id, Loc));
1673 -- Place subprogram on scope stack, and make formals visible. If there
1674 -- is a spec, the visible entity remains that of the spec.
1676 if Present (Spec_Id) then
1677 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1679 if Is_Child_Unit (Spec_Id) then
1680 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
1684 Style.Check_Identifier (Body_Id, Spec_Id);
1687 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1688 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1690 if Is_Abstract_Subprogram (Spec_Id) then
1691 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1694 Set_Convention (Body_Id, Convention (Spec_Id));
1695 Set_Has_Completion (Spec_Id);
1697 if Is_Protected_Type (Scope (Spec_Id)) then
1698 Set_Privals_Chain (Spec_Id, New_Elmt_List);
1701 -- If this is a body generated for a renaming, do not check for
1702 -- full conformance. The check is redundant, because the spec of
1703 -- the body is a copy of the spec in the renaming declaration,
1704 -- and the test can lead to spurious errors on nested defaults.
1706 if Present (Spec_Decl)
1707 and then not Comes_From_Source (N)
1709 (Nkind (Original_Node (Spec_Decl)) =
1710 N_Subprogram_Renaming_Declaration
1711 or else (Present (Corresponding_Body (Spec_Decl))
1713 Nkind (Unit_Declaration_Node
1714 (Corresponding_Body (Spec_Decl))) =
1715 N_Subprogram_Renaming_Declaration))
1721 Fully_Conformant, True, Conformant, Body_Id);
1724 -- If the body is not fully conformant, we have to decide if we
1725 -- should analyze it or not. If it has a really messed up profile
1726 -- then we probably should not analyze it, since we will get too
1727 -- many bogus messages.
1729 -- Our decision is to go ahead in the non-fully conformant case
1730 -- only if it is at least mode conformant with the spec. Note
1731 -- that the call to Check_Fully_Conformant has issued the proper
1732 -- error messages to complain about the lack of conformance.
1735 and then not Mode_Conformant (Body_Id, Spec_Id)
1741 if Spec_Id /= Body_Id then
1742 Reference_Body_Formals (Spec_Id, Body_Id);
1745 if Nkind (N) /= N_Subprogram_Body_Stub then
1746 Set_Corresponding_Spec (N, Spec_Id);
1748 -- Ada 2005 (AI-345): If the operation is a primitive operation
1749 -- of a concurrent type, the type of the first parameter has been
1750 -- replaced with the corresponding record, which is the proper
1751 -- run-time structure to use. However, within the body there may
1752 -- be uses of the formals that depend on primitive operations
1753 -- of the type (in particular calls in prefixed form) for which
1754 -- we need the original concurrent type. The operation may have
1755 -- several controlling formals, so the replacement must be done
1758 if Comes_From_Source (Spec_Id)
1759 and then Present (First_Entity (Spec_Id))
1760 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
1761 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
1763 Present (Abstract_Interfaces (Etype (First_Entity (Spec_Id))))
1766 (Corresponding_Concurrent_Type
1767 (Etype (First_Entity (Spec_Id))))
1770 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
1774 Form := First_Formal (Spec_Id);
1775 while Present (Form) loop
1776 if Etype (Form) = Typ then
1777 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
1785 -- Now make the formals visible, and place subprogram
1788 Install_Formals (Spec_Id);
1789 Last_Formal := Last_Entity (Spec_Id);
1790 Push_Scope (Spec_Id);
1792 -- Make sure that the subprogram is immediately visible. For
1793 -- child units that have no separate spec this is indispensable.
1794 -- Otherwise it is safe albeit redundant.
1796 Set_Is_Immediately_Visible (Spec_Id);
1799 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
1800 Set_Ekind (Body_Id, E_Subprogram_Body);
1801 Set_Scope (Body_Id, Scope (Spec_Id));
1802 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
1804 -- Case of subprogram body with no previous spec
1808 and then Comes_From_Source (Body_Id)
1809 and then not Suppress_Style_Checks (Body_Id)
1810 and then not In_Instance
1812 Style.Body_With_No_Spec (N);
1815 New_Overloaded_Entity (Body_Id);
1817 if Nkind (N) /= N_Subprogram_Body_Stub then
1818 Set_Acts_As_Spec (N);
1819 Generate_Definition (Body_Id);
1821 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
1822 Generate_Reference_To_Formals (Body_Id);
1823 Install_Formals (Body_Id);
1824 Push_Scope (Body_Id);
1828 -- Ada 2005 (AI-251): Check wrong placement of abstract interface
1829 -- primitives, and update anonymous access returns with limited views.
1831 if Ada_Version >= Ada_05
1832 and then Comes_From_Source (N)
1840 -- Check the type of the formals
1842 E := First_Entity (Body_Id);
1843 while Present (E) loop
1846 if Is_Access_Type (Etyp) then
1847 Etyp := Directly_Designated_Type (Etyp);
1850 if not Is_Class_Wide_Type (Etyp)
1851 and then Is_Interface (Etyp)
1853 Error_Msg_Name_1 := Chars (Defining_Entity (N));
1855 ("(Ada 2005) abstract interface primitives must be" &
1856 " defined in package specs", N);
1863 -- In case of functions, check the type of the result
1865 if Ekind (Body_Id) = E_Function then
1866 Etyp := Etype (Body_Id);
1868 if Is_Access_Type (Etyp) then
1869 Etyp := Directly_Designated_Type (Etyp);
1872 if not Is_Class_Wide_Type (Etyp)
1873 and then Is_Interface (Etyp)
1875 Error_Msg_Name_1 := Chars (Defining_Entity (N));
1877 ("(Ada 2005) abstract interface primitives must be" &
1878 " defined in package specs", N);
1882 -- If the return type is an anonymous access type whose
1883 -- designated type is the limited view of a class-wide type
1884 -- and the non-limited view is available. update the return
1885 -- type accordingly.
1887 Rtyp := Etype (Current_Scope);
1889 if Ekind (Rtyp) = E_Anonymous_Access_Type then
1890 Etyp := Directly_Designated_Type (Rtyp);
1892 if Is_Class_Wide_Type (Etyp)
1893 and then From_With_Type (Etyp)
1895 Set_Directly_Designated_Type
1896 (Etype (Current_Scope), Available_View (Etyp));
1902 -- If this is the proper body of a stub, we must verify that the stub
1903 -- conforms to the body, and to the previous spec if one was present.
1904 -- we know already that the body conforms to that spec. This test is
1905 -- only required for subprograms that come from source.
1907 if Nkind (Parent (N)) = N_Subunit
1908 and then Comes_From_Source (N)
1909 and then not Error_Posted (Body_Id)
1910 and then Nkind (Corresponding_Stub (Parent (N))) =
1911 N_Subprogram_Body_Stub
1914 Old_Id : constant Entity_Id :=
1916 (Specification (Corresponding_Stub (Parent (N))));
1918 Conformant : Boolean := False;
1921 if No (Spec_Id) then
1922 Check_Fully_Conformant (Body_Id, Old_Id);
1926 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
1928 if not Conformant then
1930 -- The stub was taken to be a new declaration. Indicate
1931 -- that it lacks a body.
1933 Set_Has_Completion (Old_Id, False);
1939 Set_Has_Completion (Body_Id);
1940 Check_Eliminated (Body_Id);
1942 if Nkind (N) = N_Subprogram_Body_Stub then
1945 elsif Present (Spec_Id)
1946 and then Expander_Active
1948 (Is_Always_Inlined (Spec_Id)
1949 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
1951 Build_Body_To_Inline (N, Spec_Id);
1954 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
1955 -- if its specification we have to install the private withed units.
1957 if Is_Compilation_Unit (Body_Id)
1958 and then Scope (Body_Id) = Standard_Standard
1960 Install_Private_With_Clauses (Body_Id);
1963 Check_Anonymous_Return;
1965 -- Now we can go on to analyze the body
1967 HSS := Handled_Statement_Sequence (N);
1968 Set_Actual_Subtypes (N, Current_Scope);
1969 Analyze_Declarations (Declarations (N));
1972 Process_End_Label (HSS, 't', Current_Scope);
1974 Check_Subprogram_Order (N);
1975 Set_Analyzed (Body_Id);
1977 -- If we have a separate spec, then the analysis of the declarations
1978 -- caused the entities in the body to be chained to the spec id, but
1979 -- we want them chained to the body id. Only the formal parameters
1980 -- end up chained to the spec id in this case.
1982 if Present (Spec_Id) then
1984 -- We must conform to the categorization of our spec
1986 Validate_Categorization_Dependency (N, Spec_Id);
1988 -- And if this is a child unit, the parent units must conform
1990 if Is_Child_Unit (Spec_Id) then
1991 Validate_Categorization_Dependency
1992 (Unit_Declaration_Node (Spec_Id), Spec_Id);
1995 if Present (Last_Formal) then
1997 (Last_Entity (Body_Id), Next_Entity (Last_Formal));
1998 Set_Next_Entity (Last_Formal, Empty);
1999 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2000 Set_Last_Entity (Spec_Id, Last_Formal);
2003 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2004 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2005 Set_First_Entity (Spec_Id, Empty);
2006 Set_Last_Entity (Spec_Id, Empty);
2010 -- If function, check return statements
2012 if Nkind (Body_Spec) = N_Function_Specification then
2017 if Present (Spec_Id) then
2023 if Return_Present (Id) then
2024 Check_Returns (HSS, 'F', Missing_Ret);
2027 Set_Has_Missing_Return (Id);
2030 elsif not Is_Machine_Code_Subprogram (Id)
2031 and then not Body_Deleted
2033 Error_Msg_N ("missing RETURN statement in function body", N);
2037 -- If procedure with No_Return, check returns
2039 elsif Nkind (Body_Spec) = N_Procedure_Specification
2040 and then Present (Spec_Id)
2041 and then No_Return (Spec_Id)
2043 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2046 -- Now we are going to check for variables that are never modified in
2047 -- the body of the procedure. We omit these checks if the first
2048 -- statement of the procedure raises an exception. In particular this
2049 -- deals with the common idiom of a stubbed function, which might
2050 -- appear as something like
2052 -- function F (A : Integer) return Some_Type;
2055 -- raise Program_Error;
2059 -- Here the purpose of X is simply to satisfy the (annoying)
2060 -- requirement in Ada that there be at least one return, and we
2061 -- certainly do not want to go posting warnings on X that it is not
2065 Stm : Node_Id := First (Statements (HSS));
2068 -- Skip initial labels (for one thing this occurs when we are in
2069 -- front end ZCX mode, but in any case it is irrelevant), and also
2070 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2072 while Nkind (Stm) = N_Label
2073 or else Nkind (Stm) in N_Push_xxx_Label
2078 -- Do the test on the original statement before expansion
2081 Ostm : constant Node_Id := Original_Node (Stm);
2084 -- If explicit raise statement, return with no checks
2086 if Nkind (Ostm) = N_Raise_Statement then
2089 -- Check for explicit call cases which likely raise an exception
2091 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2092 if Is_Entity_Name (Name (Ostm)) then
2094 Ent : constant Entity_Id := Entity (Name (Ostm));
2097 -- If the procedure is marked No_Return, then likely it
2098 -- raises an exception, but in any case it is not coming
2099 -- back here, so no need to check beyond the call.
2101 if Ekind (Ent) = E_Procedure
2102 and then No_Return (Ent)
2106 -- If the procedure name is Raise_Exception, then also
2107 -- assume that it raises an exception. The main target
2108 -- here is Ada.Exceptions.Raise_Exception, but this name
2109 -- is pretty evocative in any context! Note that the
2110 -- procedure in Ada.Exceptions is not marked No_Return
2111 -- because of the annoying case of the null exception Id.
2113 elsif Chars (Ent) = Name_Raise_Exception then
2122 -- Check for variables that are never modified
2128 -- If there is a separate spec, then transfer Never_Set_In_Source
2129 -- flags from out parameters to the corresponding entities in the
2130 -- body. The reason we do that is we want to post error flags on
2131 -- the body entities, not the spec entities.
2133 if Present (Spec_Id) then
2134 E1 := First_Entity (Spec_Id);
2135 while Present (E1) loop
2136 if Ekind (E1) = E_Out_Parameter then
2137 E2 := First_Entity (Body_Id);
2138 while Present (E2) loop
2139 exit when Chars (E1) = Chars (E2);
2143 if Present (E2) then
2144 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2152 -- Check references in body unless it was deleted. Note that the
2153 -- check of Body_Deleted here is not just for efficiency, it is
2154 -- necessary to avoid junk warnings on formal parameters.
2156 if not Body_Deleted then
2157 Check_References (Body_Id);
2160 end Analyze_Subprogram_Body;
2162 ------------------------------------
2163 -- Analyze_Subprogram_Declaration --
2164 ------------------------------------
2166 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2167 Designator : constant Entity_Id :=
2168 Analyze_Subprogram_Specification (Specification (N));
2169 Scop : constant Entity_Id := Current_Scope;
2171 -- Start of processing for Analyze_Subprogram_Declaration
2174 Generate_Definition (Designator);
2176 -- Check for RCI unit subprogram declarations for illegal inlined
2177 -- subprograms and subprograms having access parameter or limited
2178 -- parameter without Read and Write attributes (RM E.2.3(12-13)).
2180 Validate_RCI_Subprogram_Declaration (N);
2184 Defining_Entity (N),
2185 " Analyze subprogram spec. ");
2187 if Debug_Flag_C then
2188 Write_Str ("==== Compiling subprogram spec ");
2189 Write_Name (Chars (Designator));
2190 Write_Str (" from ");
2191 Write_Location (Sloc (N));
2195 New_Overloaded_Entity (Designator);
2196 Check_Delayed_Subprogram (Designator);
2198 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
2201 if Ada_Version >= Ada_05
2202 and then Comes_From_Source (N)
2203 and then Is_Dispatching_Operation (Designator)
2210 if Has_Controlling_Result (Designator) then
2211 Etyp := Etype (Designator);
2214 E := First_Entity (Designator);
2216 and then Is_Formal (E)
2217 and then not Is_Controlling_Formal (E)
2225 if Is_Access_Type (Etyp) then
2226 Etyp := Directly_Designated_Type (Etyp);
2229 if Is_Interface (Etyp)
2230 and then not Is_Abstract_Subprogram (Designator)
2231 and then not (Ekind (Designator) = E_Procedure
2232 and then Null_Present (Specification (N)))
2234 Error_Msg_Name_1 := Chars (Defining_Entity (N));
2236 ("(Ada 2005) interface subprogram % must be abstract or null",
2242 -- What is the following code for, it used to be
2244 -- ??? Set_Suppress_Elaboration_Checks
2245 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
2247 -- The following seems equivalent, but a bit dubious
2249 if Elaboration_Checks_Suppressed (Designator) then
2250 Set_Kill_Elaboration_Checks (Designator);
2253 if Scop /= Standard_Standard
2254 and then not Is_Child_Unit (Designator)
2256 Set_Categorization_From_Scope (Designator, Scop);
2258 -- For a compilation unit, check for library-unit pragmas
2260 Push_Scope (Designator);
2261 Set_Categorization_From_Pragmas (N);
2262 Validate_Categorization_Dependency (N, Designator);
2266 -- For a compilation unit, set body required. This flag will only be
2267 -- reset if a valid Import or Interface pragma is processed later on.
2269 if Nkind (Parent (N)) = N_Compilation_Unit then
2270 Set_Body_Required (Parent (N), True);
2272 if Ada_Version >= Ada_05
2273 and then Nkind (Specification (N)) = N_Procedure_Specification
2274 and then Null_Present (Specification (N))
2277 ("null procedure cannot be declared at library level", N);
2281 Generate_Reference_To_Formals (Designator);
2282 Check_Eliminated (Designator);
2284 -- Ada 2005: if procedure is declared with "is null" qualifier,
2285 -- it requires no body.
2287 if Nkind (Specification (N)) = N_Procedure_Specification
2288 and then Null_Present (Specification (N))
2290 Set_Has_Completion (Designator);
2291 Set_Is_Inlined (Designator);
2293 if Is_Protected_Type (Current_Scope) then
2295 ("protected operation cannot be a null procedure", N);
2298 end Analyze_Subprogram_Declaration;
2300 --------------------------------------
2301 -- Analyze_Subprogram_Specification --
2302 --------------------------------------
2304 -- Reminder: N here really is a subprogram specification (not a subprogram
2305 -- declaration). This procedure is called to analyze the specification in
2306 -- both subprogram bodies and subprogram declarations (specs).
2308 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
2309 Designator : constant Entity_Id := Defining_Entity (N);
2311 Formal_Typ : Entity_Id;
2312 Formals : constant List_Id := Parameter_Specifications (N);
2314 -- Start of processing for Analyze_Subprogram_Specification
2317 Generate_Definition (Designator);
2319 if Nkind (N) = N_Function_Specification then
2320 Set_Ekind (Designator, E_Function);
2321 Set_Mechanism (Designator, Default_Mechanism);
2324 Set_Ekind (Designator, E_Procedure);
2325 Set_Etype (Designator, Standard_Void_Type);
2328 -- Introduce new scope for analysis of the formals and of the
2331 Set_Scope (Designator, Current_Scope);
2333 if Present (Formals) then
2334 Push_Scope (Designator);
2335 Process_Formals (Formals, N);
2337 -- Ada 2005 (AI-345): Allow the overriding of interface primitives
2338 -- by subprograms which belong to a concurrent type implementing an
2339 -- interface. Set the parameter type of each controlling formal to
2340 -- the corresponding record type.
2342 if Ada_Version >= Ada_05 then
2343 Formal := First_Formal (Designator);
2344 while Present (Formal) loop
2345 Formal_Typ := Etype (Formal);
2347 if (Ekind (Formal_Typ) = E_Protected_Type
2348 or else Ekind (Formal_Typ) = E_Task_Type)
2349 and then Present (Corresponding_Record_Type (Formal_Typ))
2350 and then Present (Abstract_Interfaces
2351 (Corresponding_Record_Type (Formal_Typ)))
2354 Corresponding_Record_Type (Formal_Typ));
2357 Formal := Next_Formal (Formal);
2363 elsif Nkind (N) = N_Function_Specification then
2364 Analyze_Return_Type (N);
2367 if Nkind (N) = N_Function_Specification then
2368 if Nkind (Designator) = N_Defining_Operator_Symbol then
2369 Valid_Operator_Definition (Designator);
2372 May_Need_Actuals (Designator);
2374 -- Ada 2005 (AI-251): In case of primitives associated with abstract
2375 -- interface types the following error message will be reported later
2376 -- (see Analyze_Subprogram_Declaration).
2378 if Is_Abstract_Type (Etype (Designator))
2379 and then not Is_Interface (Etype (Designator))
2380 and then Nkind (Parent (N))
2381 /= N_Abstract_Subprogram_Declaration
2382 and then (Nkind (Parent (N)))
2383 /= N_Formal_Abstract_Subprogram_Declaration
2384 and then (Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
2385 or else not Is_Entity_Name (Name (Parent (N)))
2386 or else not Is_Abstract_Subprogram
2387 (Entity (Name (Parent (N)))))
2390 ("function that returns abstract type must be abstract", N);
2395 end Analyze_Subprogram_Specification;
2397 --------------------------
2398 -- Build_Body_To_Inline --
2399 --------------------------
2401 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
2402 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
2403 Original_Body : Node_Id;
2404 Body_To_Analyze : Node_Id;
2405 Max_Size : constant := 10;
2406 Stat_Count : Integer := 0;
2408 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
2409 -- Check for declarations that make inlining not worthwhile
2411 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
2412 -- Check for statements that make inlining not worthwhile: any tasking
2413 -- statement, nested at any level. Keep track of total number of
2414 -- elementary statements, as a measure of acceptable size.
2416 function Has_Pending_Instantiation return Boolean;
2417 -- If some enclosing body contains instantiations that appear before the
2418 -- corresponding generic body, the enclosing body has a freeze node so
2419 -- that it can be elaborated after the generic itself. This might
2420 -- conflict with subsequent inlinings, so that it is unsafe to try to
2421 -- inline in such a case.
2423 function Has_Single_Return return Boolean;
2424 -- In general we cannot inline functions that return unconstrained type.
2425 -- However, we can handle such functions if all return statements return
2426 -- a local variable that is the only declaration in the body of the
2427 -- function. In that case the call can be replaced by that local
2428 -- variable as is done for other inlined calls.
2430 procedure Remove_Pragmas;
2431 -- A pragma Unreferenced that mentions a formal parameter has no meaning
2432 -- when the body is inlined and the formals are rewritten. Remove it
2433 -- from body to inline. The analysis of the non-inlined body will handle
2434 -- the pragma properly.
2436 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
2437 -- If the body of the subprogram includes a call that returns an
2438 -- unconstrained type, the secondary stack is involved, and it
2439 -- is not worth inlining.
2441 ------------------------------
2442 -- Has_Excluded_Declaration --
2443 ------------------------------
2445 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
2448 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
2449 -- Nested subprograms make a given body ineligible for inlining, but
2450 -- we make an exception for instantiations of unchecked conversion.
2451 -- The body has not been analyzed yet, so check the name, and verify
2452 -- that the visible entity with that name is the predefined unit.
2454 -----------------------------
2455 -- Is_Unchecked_Conversion --
2456 -----------------------------
2458 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
2459 Id : constant Node_Id := Name (D);
2463 if Nkind (Id) = N_Identifier
2464 and then Chars (Id) = Name_Unchecked_Conversion
2466 Conv := Current_Entity (Id);
2468 elsif (Nkind (Id) = N_Selected_Component
2469 or else Nkind (Id) = N_Expanded_Name)
2470 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
2472 Conv := Current_Entity (Selector_Name (Id));
2478 return Present (Conv)
2479 and then Is_Predefined_File_Name
2480 (Unit_File_Name (Get_Source_Unit (Conv)))
2481 and then Is_Intrinsic_Subprogram (Conv);
2482 end Is_Unchecked_Conversion;
2484 -- Start of processing for Has_Excluded_Declaration
2489 while Present (D) loop
2490 if (Nkind (D) = N_Function_Instantiation
2491 and then not Is_Unchecked_Conversion (D))
2492 or else Nkind (D) = N_Protected_Type_Declaration
2493 or else Nkind (D) = N_Package_Declaration
2494 or else Nkind (D) = N_Package_Instantiation
2495 or else Nkind (D) = N_Subprogram_Body
2496 or else Nkind (D) = N_Procedure_Instantiation
2497 or else Nkind (D) = N_Task_Type_Declaration
2500 ("cannot inline & (non-allowed declaration)?", D, Subp);
2508 end Has_Excluded_Declaration;
2510 ----------------------------
2511 -- Has_Excluded_Statement --
2512 ----------------------------
2514 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
2520 while Present (S) loop
2521 Stat_Count := Stat_Count + 1;
2523 if Nkind (S) = N_Abort_Statement
2524 or else Nkind (S) = N_Asynchronous_Select
2525 or else Nkind (S) = N_Conditional_Entry_Call
2526 or else Nkind (S) = N_Delay_Relative_Statement
2527 or else Nkind (S) = N_Delay_Until_Statement
2528 or else Nkind (S) = N_Selective_Accept
2529 or else Nkind (S) = N_Timed_Entry_Call
2532 ("cannot inline & (non-allowed statement)?", S, Subp);
2535 elsif Nkind (S) = N_Block_Statement then
2536 if Present (Declarations (S))
2537 and then Has_Excluded_Declaration (Declarations (S))
2541 elsif Present (Handled_Statement_Sequence (S))
2544 (Exception_Handlers (Handled_Statement_Sequence (S)))
2546 Has_Excluded_Statement
2547 (Statements (Handled_Statement_Sequence (S))))
2552 elsif Nkind (S) = N_Case_Statement then
2553 E := First (Alternatives (S));
2554 while Present (E) loop
2555 if Has_Excluded_Statement (Statements (E)) then
2562 elsif Nkind (S) = N_If_Statement then
2563 if Has_Excluded_Statement (Then_Statements (S)) then
2567 if Present (Elsif_Parts (S)) then
2568 E := First (Elsif_Parts (S));
2569 while Present (E) loop
2570 if Has_Excluded_Statement (Then_Statements (E)) then
2577 if Present (Else_Statements (S))
2578 and then Has_Excluded_Statement (Else_Statements (S))
2583 elsif Nkind (S) = N_Loop_Statement
2584 and then Has_Excluded_Statement (Statements (S))
2593 end Has_Excluded_Statement;
2595 -------------------------------
2596 -- Has_Pending_Instantiation --
2597 -------------------------------
2599 function Has_Pending_Instantiation return Boolean is
2604 while Present (S) loop
2605 if Is_Compilation_Unit (S)
2606 or else Is_Child_Unit (S)
2609 elsif Ekind (S) = E_Package
2610 and then Has_Forward_Instantiation (S)
2619 end Has_Pending_Instantiation;
2621 ------------------------
2622 -- Has_Single_Return --
2623 ------------------------
2625 function Has_Single_Return return Boolean is
2626 Return_Statement : Node_Id := Empty;
2628 function Check_Return (N : Node_Id) return Traverse_Result;
2634 function Check_Return (N : Node_Id) return Traverse_Result is
2636 if Nkind (N) = N_Simple_Return_Statement then
2637 if Present (Expression (N))
2638 and then Is_Entity_Name (Expression (N))
2640 if No (Return_Statement) then
2641 Return_Statement := N;
2644 elsif Chars (Expression (N)) =
2645 Chars (Expression (Return_Statement))
2654 -- Expression has wrong form
2664 function Check_All_Returns is new Traverse_Func (Check_Return);
2666 -- Start of processing for Has_Single_Return
2669 return Check_All_Returns (N) = OK
2670 and then Present (Declarations (N))
2671 and then Present (First (Declarations (N)))
2672 and then Chars (Expression (Return_Statement)) =
2673 Chars (Defining_Identifier (First (Declarations (N))));
2674 end Has_Single_Return;
2676 --------------------
2677 -- Remove_Pragmas --
2678 --------------------
2680 procedure Remove_Pragmas is
2685 Decl := First (Declarations (Body_To_Analyze));
2686 while Present (Decl) loop
2689 if Nkind (Decl) = N_Pragma
2690 and then Chars (Decl) = Name_Unreferenced
2699 --------------------------
2700 -- Uses_Secondary_Stack --
2701 --------------------------
2703 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
2704 function Check_Call (N : Node_Id) return Traverse_Result;
2705 -- Look for function calls that return an unconstrained type
2711 function Check_Call (N : Node_Id) return Traverse_Result is
2713 if Nkind (N) = N_Function_Call
2714 and then Is_Entity_Name (Name (N))
2715 and then Is_Composite_Type (Etype (Entity (Name (N))))
2716 and then not Is_Constrained (Etype (Entity (Name (N))))
2719 ("cannot inline & (call returns unconstrained type)?",
2727 function Check_Calls is new Traverse_Func (Check_Call);
2730 return Check_Calls (Bod) = Abandon;
2731 end Uses_Secondary_Stack;
2733 -- Start of processing for Build_Body_To_Inline
2736 if Nkind (Decl) = N_Subprogram_Declaration
2737 and then Present (Body_To_Inline (Decl))
2739 return; -- Done already.
2741 -- Functions that return unconstrained composite types require
2742 -- secondary stack handling, and cannot currently be inlined, unless
2743 -- all return statements return a local variable that is the first
2744 -- local declaration in the body.
2746 elsif Ekind (Subp) = E_Function
2747 and then not Is_Scalar_Type (Etype (Subp))
2748 and then not Is_Access_Type (Etype (Subp))
2749 and then not Is_Constrained (Etype (Subp))
2751 if not Has_Single_Return then
2753 ("cannot inline & (unconstrained return type)?", N, Subp);
2757 -- Ditto for functions that return controlled types, where controlled
2758 -- actions interfere in complex ways with inlining.
2760 elsif Ekind (Subp) = E_Function
2761 and then Controlled_Type (Etype (Subp))
2764 ("cannot inline & (controlled return type)?", N, Subp);
2768 if Present (Declarations (N))
2769 and then Has_Excluded_Declaration (Declarations (N))
2774 if Present (Handled_Statement_Sequence (N)) then
2775 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
2777 ("cannot inline& (exception handler)?",
2778 First (Exception_Handlers (Handled_Statement_Sequence (N))),
2782 Has_Excluded_Statement
2783 (Statements (Handled_Statement_Sequence (N)))
2789 -- We do not inline a subprogram that is too large, unless it is
2790 -- marked Inline_Always. This pragma does not suppress the other
2791 -- checks on inlining (forbidden declarations, handlers, etc).
2793 if Stat_Count > Max_Size
2794 and then not Is_Always_Inlined (Subp)
2796 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
2800 if Has_Pending_Instantiation then
2802 ("cannot inline& (forward instance within enclosing body)?",
2807 -- Within an instance, the body to inline must be treated as a nested
2808 -- generic, so that the proper global references are preserved.
2811 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
2812 Original_Body := Copy_Generic_Node (N, Empty, True);
2814 Original_Body := Copy_Separate_Tree (N);
2817 -- We need to capture references to the formals in order to substitute
2818 -- the actuals at the point of inlining, i.e. instantiation. To treat
2819 -- the formals as globals to the body to inline, we nest it within
2820 -- a dummy parameterless subprogram, declared within the real one.
2821 -- To avoid generating an internal name (which is never public, and
2822 -- which affects serial numbers of other generated names), we use
2823 -- an internal symbol that cannot conflict with user declarations.
2825 Set_Parameter_Specifications (Specification (Original_Body), No_List);
2826 Set_Defining_Unit_Name
2827 (Specification (Original_Body),
2828 Make_Defining_Identifier (Sloc (N), Name_uParent));
2829 Set_Corresponding_Spec (Original_Body, Empty);
2831 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
2833 -- Set return type of function, which is also global and does not need
2836 if Ekind (Subp) = E_Function then
2837 Set_Result_Definition (Specification (Body_To_Analyze),
2838 New_Occurrence_Of (Etype (Subp), Sloc (N)));
2841 if No (Declarations (N)) then
2842 Set_Declarations (N, New_List (Body_To_Analyze));
2844 Append (Body_To_Analyze, Declarations (N));
2847 Expander_Mode_Save_And_Set (False);
2850 Analyze (Body_To_Analyze);
2851 Push_Scope (Defining_Entity (Body_To_Analyze));
2852 Save_Global_References (Original_Body);
2854 Remove (Body_To_Analyze);
2856 Expander_Mode_Restore;
2862 -- If secondary stk used there is no point in inlining. We have
2863 -- already issued the warning in this case, so nothing to do.
2865 if Uses_Secondary_Stack (Body_To_Analyze) then
2869 Set_Body_To_Inline (Decl, Original_Body);
2870 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
2871 Set_Is_Inlined (Subp);
2872 end Build_Body_To_Inline;
2878 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
2880 -- Do not emit warning if this is a predefined unit which is not
2881 -- the main unit. With validity checks enabled, some predefined
2882 -- subprograms may contain nested subprograms and become ineligible
2885 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
2886 and then not In_Extended_Main_Source_Unit (Subp)
2890 elsif Is_Always_Inlined (Subp) then
2892 -- Remove last character (question mark) to make this into an error,
2893 -- because the Inline_Always pragma cannot be obeyed.
2895 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
2897 elsif Ineffective_Inline_Warnings then
2898 Error_Msg_NE (Msg, N, Subp);
2902 -----------------------
2903 -- Check_Conformance --
2904 -----------------------
2906 procedure Check_Conformance
2907 (New_Id : Entity_Id;
2909 Ctype : Conformance_Type;
2911 Conforms : out Boolean;
2912 Err_Loc : Node_Id := Empty;
2913 Get_Inst : Boolean := False;
2914 Skip_Controlling_Formals : Boolean := False)
2916 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
2917 -- Post error message for conformance error on given node. Two messages
2918 -- are output. The first points to the previous declaration with a
2919 -- general "no conformance" message. The second is the detailed reason,
2920 -- supplied as Msg. The parameter N provide information for a possible
2921 -- & insertion in the message, and also provides the location for
2922 -- posting the message in the absence of a specified Err_Loc location.
2924 -----------------------
2925 -- Conformance_Error --
2926 -----------------------
2928 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
2935 if No (Err_Loc) then
2941 Error_Msg_Sloc := Sloc (Old_Id);
2944 when Type_Conformant =>
2946 ("not type conformant with declaration#!", Enode);
2948 when Mode_Conformant =>
2949 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2951 ("not mode conformant with operation inherited#!",
2955 ("not mode conformant with declaration#!", Enode);
2958 when Subtype_Conformant =>
2959 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2961 ("not subtype conformant with operation inherited#!",
2965 ("not subtype conformant with declaration#!", Enode);
2968 when Fully_Conformant =>
2969 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2971 ("not fully conformant with operation inherited#!",
2975 ("not fully conformant with declaration#!", Enode);
2979 Error_Msg_NE (Msg, Enode, N);
2981 end Conformance_Error;
2985 Old_Type : constant Entity_Id := Etype (Old_Id);
2986 New_Type : constant Entity_Id := Etype (New_Id);
2987 Old_Formal : Entity_Id;
2988 New_Formal : Entity_Id;
2989 Access_Types_Match : Boolean;
2990 Old_Formal_Base : Entity_Id;
2991 New_Formal_Base : Entity_Id;
2993 -- Start of processing for Check_Conformance
2998 -- We need a special case for operators, since they don't appear
3001 if Ctype = Type_Conformant then
3002 if Ekind (New_Id) = E_Operator
3003 and then Operator_Matches_Spec (New_Id, Old_Id)
3009 -- If both are functions/operators, check return types conform
3011 if Old_Type /= Standard_Void_Type
3012 and then New_Type /= Standard_Void_Type
3014 if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3015 Conformance_Error ("\return type does not match!", New_Id);
3019 -- Ada 2005 (AI-231): In case of anonymous access types check the
3020 -- null-exclusion and access-to-constant attributes match.
3022 if Ada_Version >= Ada_05
3023 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3025 (Can_Never_Be_Null (Old_Type)
3026 /= Can_Never_Be_Null (New_Type)
3027 or else Is_Access_Constant (Etype (Old_Type))
3028 /= Is_Access_Constant (Etype (New_Type)))
3030 Conformance_Error ("\return type does not match!", New_Id);
3034 -- If either is a function/operator and the other isn't, error
3036 elsif Old_Type /= Standard_Void_Type
3037 or else New_Type /= Standard_Void_Type
3039 Conformance_Error ("\functions can only match functions!", New_Id);
3043 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
3044 -- If this is a renaming as body, refine error message to indicate that
3045 -- the conflict is with the original declaration. If the entity is not
3046 -- frozen, the conventions don't have to match, the one of the renamed
3047 -- entity is inherited.
3049 if Ctype >= Subtype_Conformant then
3050 if Convention (Old_Id) /= Convention (New_Id) then
3052 if not Is_Frozen (New_Id) then
3055 elsif Present (Err_Loc)
3056 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
3057 and then Present (Corresponding_Spec (Err_Loc))
3059 Error_Msg_Name_1 := Chars (New_Id);
3061 Name_Ada + Convention_Id'Pos (Convention (New_Id));
3063 Conformance_Error ("\prior declaration for% has convention %!");
3066 Conformance_Error ("\calling conventions do not match!");
3071 elsif Is_Formal_Subprogram (Old_Id)
3072 or else Is_Formal_Subprogram (New_Id)
3074 Conformance_Error ("\formal subprograms not allowed!");
3079 -- Deal with parameters
3081 -- Note: we use the entity information, rather than going directly
3082 -- to the specification in the tree. This is not only simpler, but
3083 -- absolutely necessary for some cases of conformance tests between
3084 -- operators, where the declaration tree simply does not exist!
3086 Old_Formal := First_Formal (Old_Id);
3087 New_Formal := First_Formal (New_Id);
3089 while Present (Old_Formal) and then Present (New_Formal) loop
3090 if Is_Controlling_Formal (Old_Formal)
3091 and then Is_Controlling_Formal (New_Formal)
3092 and then Skip_Controlling_Formals
3094 goto Skip_Controlling_Formal;
3097 if Ctype = Fully_Conformant then
3099 -- Names must match. Error message is more accurate if we do
3100 -- this before checking that the types of the formals match.
3102 if Chars (Old_Formal) /= Chars (New_Formal) then
3103 Conformance_Error ("\name & does not match!", New_Formal);
3105 -- Set error posted flag on new formal as well to stop
3106 -- junk cascaded messages in some cases.
3108 Set_Error_Posted (New_Formal);
3113 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
3114 -- case occurs whenever a subprogram is being renamed and one of its
3115 -- parameters imposes a null exclusion. For example:
3117 -- type T is null record;
3118 -- type Acc_T is access T;
3119 -- subtype Acc_T_Sub is Acc_T;
3121 -- procedure P (Obj : not null Acc_T_Sub); -- itype
3122 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
3125 Old_Formal_Base := Etype (Old_Formal);
3126 New_Formal_Base := Etype (New_Formal);
3129 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
3130 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
3133 Access_Types_Match := Ada_Version >= Ada_05
3135 -- Ensure that this rule is only applied when New_Id is a
3136 -- renaming of Old_Id.
3138 and then Nkind (Parent (Parent (New_Id))) =
3139 N_Subprogram_Renaming_Declaration
3140 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
3141 and then Present (Entity (Name (Parent (Parent (New_Id)))))
3142 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
3144 -- Now handle the allowed access-type case
3146 and then Is_Access_Type (Old_Formal_Base)
3147 and then Is_Access_Type (New_Formal_Base)
3149 -- The type kinds must match. The only exception occurs with
3150 -- multiple generics of the form:
3153 -- type F is private; type A is private;
3154 -- type F_Ptr is access F; type A_Ptr is access A;
3155 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
3156 -- package F_Pack is ... package A_Pack is
3157 -- package F_Inst is
3158 -- new F_Pack (A, A_Ptr, A_P);
3160 -- When checking for conformance between the parameters of A_P
3161 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
3162 -- because the compiler has transformed A_Ptr into a subtype of
3163 -- F_Ptr. We catch this case in the code below.
3165 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
3167 (Is_Generic_Type (Old_Formal_Base)
3168 and then Is_Generic_Type (New_Formal_Base)
3169 and then Is_Internal (New_Formal_Base)
3170 and then Etype (Etype (New_Formal_Base)) =
3172 and then Directly_Designated_Type (Old_Formal_Base) =
3173 Directly_Designated_Type (New_Formal_Base)
3174 and then ((Is_Itype (Old_Formal_Base)
3175 and then Can_Never_Be_Null (Old_Formal_Base))
3177 (Is_Itype (New_Formal_Base)
3178 and then Can_Never_Be_Null (New_Formal_Base)));
3180 -- Types must always match. In the visible part of an instance,
3181 -- usual overloading rules for dispatching operations apply, and
3182 -- we check base types (not the actual subtypes).
3184 if In_Instance_Visible_Part
3185 and then Is_Dispatching_Operation (New_Id)
3187 if not Conforming_Types
3188 (T1 => Base_Type (Etype (Old_Formal)),
3189 T2 => Base_Type (Etype (New_Formal)),
3191 Get_Inst => Get_Inst)
3192 and then not Access_Types_Match
3194 Conformance_Error ("\type of & does not match!", New_Formal);
3198 elsif not Conforming_Types
3199 (T1 => Old_Formal_Base,
3200 T2 => New_Formal_Base,
3202 Get_Inst => Get_Inst)
3203 and then not Access_Types_Match
3205 Conformance_Error ("\type of & does not match!", New_Formal);
3209 -- For mode conformance, mode must match
3211 if Ctype >= Mode_Conformant then
3212 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
3213 Conformance_Error ("\mode of & does not match!", New_Formal);
3216 -- Part of mode conformance for access types is having the same
3217 -- constant modifier.
3219 elsif Access_Types_Match
3220 and then Is_Access_Constant (Old_Formal_Base) /=
3221 Is_Access_Constant (New_Formal_Base)
3224 ("\constant modifier does not match!", New_Formal);
3229 if Ctype >= Subtype_Conformant then
3231 -- Ada 2005 (AI-231): In case of anonymous access types check
3232 -- the null-exclusion and access-to-constant attributes must
3235 if Ada_Version >= Ada_05
3236 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
3237 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
3239 (Can_Never_Be_Null (Old_Formal) /=
3240 Can_Never_Be_Null (New_Formal)
3242 Is_Access_Constant (Etype (Old_Formal)) /=
3243 Is_Access_Constant (Etype (New_Formal)))
3245 -- It is allowed to omit the null-exclusion in case of stream
3246 -- attribute subprograms. We recognize stream subprograms
3247 -- through their TSS-generated suffix.
3250 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
3252 if TSS_Name /= TSS_Stream_Read
3253 and then TSS_Name /= TSS_Stream_Write
3254 and then TSS_Name /= TSS_Stream_Input
3255 and then TSS_Name /= TSS_Stream_Output
3258 ("\type of & does not match!", New_Formal);
3265 -- Full conformance checks
3267 if Ctype = Fully_Conformant then
3269 -- We have checked already that names match
3271 if Parameter_Mode (Old_Formal) = E_In_Parameter then
3273 -- Check default expressions for in parameters
3276 NewD : constant Boolean :=
3277 Present (Default_Value (New_Formal));
3278 OldD : constant Boolean :=
3279 Present (Default_Value (Old_Formal));
3281 if NewD or OldD then
3283 -- The old default value has been analyzed because the
3284 -- current full declaration will have frozen everything
3285 -- before. The new default value has not been analyzed,
3286 -- so analyze it now before we check for conformance.
3289 Push_Scope (New_Id);
3290 Analyze_Per_Use_Expression
3291 (Default_Value (New_Formal), Etype (New_Formal));
3295 if not (NewD and OldD)
3296 or else not Fully_Conformant_Expressions
3297 (Default_Value (Old_Formal),
3298 Default_Value (New_Formal))
3301 ("\default expression for & does not match!",
3310 -- A couple of special checks for Ada 83 mode. These checks are
3311 -- skipped if either entity is an operator in package Standard,
3312 -- or if either old or new instance is not from the source program.
3314 if Ada_Version = Ada_83
3315 and then Sloc (Old_Id) > Standard_Location
3316 and then Sloc (New_Id) > Standard_Location
3317 and then Comes_From_Source (Old_Id)
3318 and then Comes_From_Source (New_Id)
3321 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
3322 New_Param : constant Node_Id := Declaration_Node (New_Formal);
3325 -- Explicit IN must be present or absent in both cases. This
3326 -- test is required only in the full conformance case.
3328 if In_Present (Old_Param) /= In_Present (New_Param)
3329 and then Ctype = Fully_Conformant
3332 ("\(Ada 83) IN must appear in both declarations",
3337 -- Grouping (use of comma in param lists) must be the same
3338 -- This is where we catch a misconformance like:
3341 -- A : Integer; B : Integer
3343 -- which are represented identically in the tree except
3344 -- for the setting of the flags More_Ids and Prev_Ids.
3346 if More_Ids (Old_Param) /= More_Ids (New_Param)
3347 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
3350 ("\grouping of & does not match!", New_Formal);
3356 -- This label is required when skipping controlling formals
3358 <<Skip_Controlling_Formal>>
3360 Next_Formal (Old_Formal);
3361 Next_Formal (New_Formal);
3364 if Present (Old_Formal) then
3365 Conformance_Error ("\too few parameters!");
3368 elsif Present (New_Formal) then
3369 Conformance_Error ("\too many parameters!", New_Formal);
3372 end Check_Conformance;
3374 -----------------------
3375 -- Check_Conventions --
3376 -----------------------
3378 procedure Check_Conventions (Typ : Entity_Id) is
3380 function Skip_Check (Op : Entity_Id) return Boolean;
3381 pragma Inline (Skip_Check);
3382 -- A small optimization: skip the predefined dispatching operations,
3383 -- since they always have the same convention. Also do not consider
3384 -- abstract primitives since those are left by an erroneous overriding.
3385 -- This function returns True for any operation that is thus exempted
3386 -- exempted from checking.
3388 procedure Check_Convention
3390 Search_From : Elmt_Id);
3391 -- Verify that the convention of inherited dispatching operation Op is
3392 -- consistent among all subprograms it overrides. In order to minimize
3393 -- the search, Search_From is utilized to designate a specific point in
3394 -- the list rather than iterating over the whole list once more.
3396 ----------------------
3397 -- Check_Convention --
3398 ----------------------
3400 procedure Check_Convention
3402 Search_From : Elmt_Id)
3404 procedure Error_Msg_Operation (Op : Entity_Id);
3405 -- Emit a continuation to an error message depicting the kind, name,
3406 -- convention and source location of subprogram Op.
3408 -------------------------
3409 -- Error_Msg_Operation --
3410 -------------------------
3412 procedure Error_Msg_Operation (Op : Entity_Id) is
3414 Error_Msg_Name_1 := Chars (Op);
3416 -- Error messages of primitive subprograms do not contain a
3417 -- convention attribute since the convention may have been first
3418 -- inherited from a parent subprogram, then changed by a pragma.
3420 if Comes_From_Source (Op) then
3421 Error_Msg_Sloc := Sloc (Op);
3423 ("\ primitive % defined #", Typ);
3426 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
3428 if Present (Abstract_Interface_Alias (Op)) then
3429 Error_Msg_Sloc := Sloc (Abstract_Interface_Alias (Op));
3430 Error_Msg_N ("\\overridden operation % with " &
3431 "convention % defined #", Typ);
3433 else pragma Assert (Present (Alias (Op)));
3434 Error_Msg_Sloc := Sloc (Alias (Op));
3435 Error_Msg_N ("\\inherited operation % with " &
3436 "convention % defined #", Typ);
3439 end Error_Msg_Operation;
3443 Second_Prim_Op : Entity_Id;
3444 Second_Prim_Op_Elmt : Elmt_Id;
3446 -- Start of processing for Check_Convention
3449 Second_Prim_Op_Elmt := Next_Elmt (Search_From);
3450 while Present (Second_Prim_Op_Elmt) loop
3451 Second_Prim_Op := Node (Second_Prim_Op_Elmt);
3453 if not Skip_Check (Second_Prim_Op)
3454 and then Chars (Second_Prim_Op) = Chars (Op)
3455 and then Type_Conformant (Second_Prim_Op, Op)
3456 and then Convention (Second_Prim_Op) /= Convention (Op)
3459 ("inconsistent conventions in primitive operations", Typ);
3461 Error_Msg_Operation (Op);
3462 Error_Msg_Operation (Second_Prim_Op);
3464 -- Avoid cascading errors
3469 Next_Elmt (Second_Prim_Op_Elmt);
3471 end Check_Convention;
3477 function Skip_Check (Op : Entity_Id) return Boolean is
3479 return Is_Predefined_Dispatching_Operation (Op)
3480 or else Is_Abstract_Subprogram (Op);
3485 Prim_Op : Entity_Id;
3486 Prim_Op_Elmt : Elmt_Id;
3488 -- Start of processing for Check_Conventions
3491 -- The algorithm checks every overriding dispatching operation against
3492 -- all the corresponding overridden dispatching operations, detecting
3493 -- differences in coventions.
3495 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
3496 while Present (Prim_Op_Elmt) loop
3497 Prim_Op := Node (Prim_Op_Elmt);
3499 -- A small optimization: skip the predefined dispatching operations
3500 -- since they always have the same convention. Also avoid processing
3501 -- of abstract primitives left from an erroneous overriding.
3503 if not Skip_Check (Prim_Op) then
3506 Search_From => Prim_Op_Elmt);
3509 Next_Elmt (Prim_Op_Elmt);
3511 end Check_Conventions;
3513 ------------------------------
3514 -- Check_Delayed_Subprogram --
3515 ------------------------------
3517 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
3520 procedure Possible_Freeze (T : Entity_Id);
3521 -- T is the type of either a formal parameter or of the return type.
3522 -- If T is not yet frozen and needs a delayed freeze, then the
3523 -- subprogram itself must be delayed.
3525 ---------------------
3526 -- Possible_Freeze --
3527 ---------------------
3529 procedure Possible_Freeze (T : Entity_Id) is
3531 if Has_Delayed_Freeze (T)
3532 and then not Is_Frozen (T)
3534 Set_Has_Delayed_Freeze (Designator);
3536 elsif Is_Access_Type (T)
3537 and then Has_Delayed_Freeze (Designated_Type (T))
3538 and then not Is_Frozen (Designated_Type (T))
3540 Set_Has_Delayed_Freeze (Designator);
3542 end Possible_Freeze;
3544 -- Start of processing for Check_Delayed_Subprogram
3547 -- Never need to freeze abstract subprogram
3549 if Ekind (Designator) /= E_Subprogram_Type
3550 and then Is_Abstract_Subprogram (Designator)
3554 -- Need delayed freeze if return type itself needs a delayed
3555 -- freeze and is not yet frozen.
3557 Possible_Freeze (Etype (Designator));
3558 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
3560 -- Need delayed freeze if any of the formal types themselves need
3561 -- a delayed freeze and are not yet frozen.
3563 F := First_Formal (Designator);
3564 while Present (F) loop
3565 Possible_Freeze (Etype (F));
3566 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
3571 -- Mark functions that return by reference. Note that it cannot be
3572 -- done for delayed_freeze subprograms because the underlying
3573 -- returned type may not be known yet (for private types)
3575 if not Has_Delayed_Freeze (Designator)
3576 and then Expander_Active
3579 Typ : constant Entity_Id := Etype (Designator);
3580 Utyp : constant Entity_Id := Underlying_Type (Typ);
3583 if Is_Inherently_Limited_Type (Typ) then
3584 Set_Returns_By_Ref (Designator);
3586 elsif Present (Utyp) and then CW_Or_Controlled_Type (Utyp) then
3587 Set_Returns_By_Ref (Designator);
3591 end Check_Delayed_Subprogram;
3593 ------------------------------------
3594 -- Check_Discriminant_Conformance --
3595 ------------------------------------
3597 procedure Check_Discriminant_Conformance
3602 Old_Discr : Entity_Id := First_Discriminant (Prev);
3603 New_Discr : Node_Id := First (Discriminant_Specifications (N));
3604 New_Discr_Id : Entity_Id;
3605 New_Discr_Type : Entity_Id;
3607 procedure Conformance_Error (Msg : String; N : Node_Id);
3608 -- Post error message for conformance error on given node. Two messages
3609 -- are output. The first points to the previous declaration with a
3610 -- general "no conformance" message. The second is the detailed reason,
3611 -- supplied as Msg. The parameter N provide information for a possible
3612 -- & insertion in the message.
3614 -----------------------
3615 -- Conformance_Error --
3616 -----------------------
3618 procedure Conformance_Error (Msg : String; N : Node_Id) is
3620 Error_Msg_Sloc := Sloc (Prev_Loc);
3621 Error_Msg_N ("not fully conformant with declaration#!", N);
3622 Error_Msg_NE (Msg, N, N);
3623 end Conformance_Error;
3625 -- Start of processing for Check_Discriminant_Conformance
3628 while Present (Old_Discr) and then Present (New_Discr) loop
3630 New_Discr_Id := Defining_Identifier (New_Discr);
3632 -- The subtype mark of the discriminant on the full type has not
3633 -- been analyzed so we do it here. For an access discriminant a new
3636 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
3638 Access_Definition (N, Discriminant_Type (New_Discr));
3641 Analyze (Discriminant_Type (New_Discr));
3642 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
3645 if not Conforming_Types
3646 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
3648 Conformance_Error ("type of & does not match!", New_Discr_Id);
3651 -- Treat the new discriminant as an occurrence of the old one,
3652 -- for navigation purposes, and fill in some semantic
3653 -- information, for completeness.
3655 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
3656 Set_Etype (New_Discr_Id, Etype (Old_Discr));
3657 Set_Scope (New_Discr_Id, Scope (Old_Discr));
3662 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
3663 Conformance_Error ("name & does not match!", New_Discr_Id);
3667 -- Default expressions must match
3670 NewD : constant Boolean :=
3671 Present (Expression (New_Discr));
3672 OldD : constant Boolean :=
3673 Present (Expression (Parent (Old_Discr)));
3676 if NewD or OldD then
3678 -- The old default value has been analyzed and expanded,
3679 -- because the current full declaration will have frozen
3680 -- everything before. The new default values have not been
3681 -- expanded, so expand now to check conformance.
3684 Analyze_Per_Use_Expression
3685 (Expression (New_Discr), New_Discr_Type);
3688 if not (NewD and OldD)
3689 or else not Fully_Conformant_Expressions
3690 (Expression (Parent (Old_Discr)),
3691 Expression (New_Discr))
3695 ("default expression for & does not match!",
3702 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
3704 if Ada_Version = Ada_83 then
3706 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
3709 -- Grouping (use of comma in param lists) must be the same
3710 -- This is where we catch a misconformance like:
3713 -- A : Integer; B : Integer
3715 -- which are represented identically in the tree except
3716 -- for the setting of the flags More_Ids and Prev_Ids.
3718 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
3719 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
3722 ("grouping of & does not match!", New_Discr_Id);
3728 Next_Discriminant (Old_Discr);
3732 if Present (Old_Discr) then
3733 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
3736 elsif Present (New_Discr) then
3738 ("too many discriminants!", Defining_Identifier (New_Discr));
3741 end Check_Discriminant_Conformance;
3743 ----------------------------
3744 -- Check_Fully_Conformant --
3745 ----------------------------
3747 procedure Check_Fully_Conformant
3748 (New_Id : Entity_Id;
3750 Err_Loc : Node_Id := Empty)
3755 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
3756 end Check_Fully_Conformant;
3758 ---------------------------
3759 -- Check_Mode_Conformant --
3760 ---------------------------
3762 procedure Check_Mode_Conformant
3763 (New_Id : Entity_Id;
3765 Err_Loc : Node_Id := Empty;
3766 Get_Inst : Boolean := False)
3772 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
3773 end Check_Mode_Conformant;
3775 --------------------------------
3776 -- Check_Overriding_Indicator --
3777 --------------------------------
3779 procedure Check_Overriding_Indicator
3781 Overridden_Subp : Entity_Id;
3782 Is_Primitive : Boolean)
3788 -- No overriding indicator for literals
3790 if Ekind (Subp) = E_Enumeration_Literal then
3793 elsif Ekind (Subp) = E_Entry then
3794 Decl := Parent (Subp);
3797 Decl := Unit_Declaration_Node (Subp);
3800 if Nkind (Decl) = N_Subprogram_Body
3801 or else Nkind (Decl) = N_Subprogram_Body_Stub
3802 or else Nkind (Decl) = N_Subprogram_Declaration
3803 or else Nkind (Decl) = N_Abstract_Subprogram_Declaration
3804 or else Nkind (Decl) = N_Subprogram_Renaming_Declaration
3806 Spec := Specification (Decl);
3808 elsif Nkind (Decl) = N_Entry_Declaration then
3815 if Present (Overridden_Subp) then
3816 if Must_Not_Override (Spec) then
3817 Error_Msg_Sloc := Sloc (Overridden_Subp);
3819 if Ekind (Subp) = E_Entry then
3821 ("entry & overrides inherited operation #", Spec, Subp);
3824 ("subprogram & overrides inherited operation #", Spec, Subp);
3828 -- If Subp is an operator, it may override a predefined operation.
3829 -- In that case overridden_subp is empty because of our implicit
3830 -- representation for predefined operators. We have to check whether the
3831 -- signature of Subp matches that of a predefined operator. Note that
3832 -- first argument provides the name of the operator, and the second
3833 -- argument the signature that may match that of a standard operation.
3835 elsif Nkind (Subp) = N_Defining_Operator_Symbol
3836 and then Must_Not_Override (Spec)
3838 if Operator_Matches_Spec (Subp, Subp) then
3840 ("subprogram & overrides predefined operator ",
3844 elsif Must_Override (Spec) then
3845 if Ekind (Subp) = E_Entry then
3846 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
3848 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
3849 if not Operator_Matches_Spec (Subp, Subp) then
3851 ("subprogram & is not overriding", Spec, Subp);
3855 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
3858 -- If the operation is marked "not overriding" and it's not primitive
3859 -- then an error is issued, unless this is an operation of a task or
3860 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
3861 -- has been specified have already been checked above.
3863 elsif Must_Not_Override (Spec)
3864 and then not Is_Primitive
3865 and then Ekind (Subp) /= E_Entry
3866 and then Ekind (Scope (Subp)) /= E_Protected_Type
3869 ("overriding indicator only allowed if subprogram is primitive",
3874 end Check_Overriding_Indicator;
3880 -- Note: this procedure needs to know far too much about how the expander
3881 -- messes with exceptions. The use of the flag Exception_Junk and the
3882 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
3883 -- works, but is not very clean. It would be better if the expansion
3884 -- routines would leave Original_Node working nicely, and we could use
3885 -- Original_Node here to ignore all the peculiar expander messing ???
3887 procedure Check_Returns
3891 Proc : Entity_Id := Empty)
3895 procedure Check_Statement_Sequence (L : List_Id);
3896 -- Internal recursive procedure to check a list of statements for proper
3897 -- termination by a return statement (or a transfer of control or a
3898 -- compound statement that is itself internally properly terminated).
3900 ------------------------------
3901 -- Check_Statement_Sequence --
3902 ------------------------------
3904 procedure Check_Statement_Sequence (L : List_Id) is
3909 Raise_Exception_Call : Boolean;
3910 -- Set True if statement sequence terminated by Raise_Exception call
3911 -- or a Reraise_Occurrence call.
3914 Raise_Exception_Call := False;
3916 -- Get last real statement
3918 Last_Stm := Last (L);
3920 -- Deal with digging out exception handler statement sequences that
3921 -- have been transformed by the local raise to goto optimization.
3922 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
3923 -- optimization has occurred, we are looking at something like:
3926 -- original stmts in block
3930 -- goto L1; | omitted if No_Exception_Propagation
3935 -- goto L3; -- skip handler when exception not raised
3937 -- <<L1>> -- target label for local exception
3951 -- and what we have to do is to dig out the estmts1 and estmts2
3952 -- sequences (which were the original sequences of statements in
3953 -- the exception handlers) and check them.
3955 if Nkind (Last_Stm) = N_Label
3956 and then Exception_Junk (Last_Stm)
3962 exit when Nkind (Stm) /= N_Block_Statement;
3963 exit when not Exception_Junk (Stm);
3966 exit when Nkind (Stm) /= N_Label;
3967 exit when not Exception_Junk (Stm);
3968 Check_Statement_Sequence
3969 (Statements (Handled_Statement_Sequence (Next (Stm))));
3974 exit when Nkind (Stm) /= N_Goto_Statement;
3975 exit when not Exception_Junk (Stm);
3979 -- Don't count pragmas
3981 while Nkind (Last_Stm) = N_Pragma
3983 -- Don't count call to SS_Release (can happen after Raise_Exception)
3986 (Nkind (Last_Stm) = N_Procedure_Call_Statement
3988 Nkind (Name (Last_Stm)) = N_Identifier
3990 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
3992 -- Don't count exception junk
3995 ((Nkind (Last_Stm) = N_Goto_Statement
3996 or else Nkind (Last_Stm) = N_Label
3997 or else Nkind (Last_Stm) = N_Object_Declaration)
3998 and then Exception_Junk (Last_Stm))
3999 or else Nkind (Last_Stm) in N_Push_xxx_Label
4000 or else Nkind (Last_Stm) in N_Pop_xxx_Label
4005 -- Here we have the "real" last statement
4007 Kind := Nkind (Last_Stm);
4009 -- Transfer of control, OK. Note that in the No_Return procedure
4010 -- case, we already diagnosed any explicit return statements, so
4011 -- we can treat them as OK in this context.
4013 if Is_Transfer (Last_Stm) then
4016 -- Check cases of explicit non-indirect procedure calls
4018 elsif Kind = N_Procedure_Call_Statement
4019 and then Is_Entity_Name (Name (Last_Stm))
4021 -- Check call to Raise_Exception procedure which is treated
4022 -- specially, as is a call to Reraise_Occurrence.
4024 -- We suppress the warning in these cases since it is likely that
4025 -- the programmer really does not expect to deal with the case
4026 -- of Null_Occurrence, and thus would find a warning about a
4027 -- missing return curious, and raising Program_Error does not
4028 -- seem such a bad behavior if this does occur.
4030 -- Note that in the Ada 2005 case for Raise_Exception, the actual
4031 -- behavior will be to raise Constraint_Error (see AI-329).
4033 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
4035 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
4037 Raise_Exception_Call := True;
4039 -- For Raise_Exception call, test first argument, if it is
4040 -- an attribute reference for a 'Identity call, then we know
4041 -- that the call cannot possibly return.
4044 Arg : constant Node_Id :=
4045 Original_Node (First_Actual (Last_Stm));
4047 if Nkind (Arg) = N_Attribute_Reference
4048 and then Attribute_Name (Arg) = Name_Identity
4055 -- If statement, need to look inside if there is an else and check
4056 -- each constituent statement sequence for proper termination.
4058 elsif Kind = N_If_Statement
4059 and then Present (Else_Statements (Last_Stm))
4061 Check_Statement_Sequence (Then_Statements (Last_Stm));
4062 Check_Statement_Sequence (Else_Statements (Last_Stm));
4064 if Present (Elsif_Parts (Last_Stm)) then
4066 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
4069 while Present (Elsif_Part) loop
4070 Check_Statement_Sequence (Then_Statements (Elsif_Part));
4078 -- Case statement, check each case for proper termination
4080 elsif Kind = N_Case_Statement then
4085 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
4086 while Present (Case_Alt) loop
4087 Check_Statement_Sequence (Statements (Case_Alt));
4088 Next_Non_Pragma (Case_Alt);
4094 -- Block statement, check its handled sequence of statements
4096 elsif Kind = N_Block_Statement then
4102 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
4111 -- Loop statement. If there is an iteration scheme, we can definitely
4112 -- fall out of the loop. Similarly if there is an exit statement, we
4113 -- can fall out. In either case we need a following return.
4115 elsif Kind = N_Loop_Statement then
4116 if Present (Iteration_Scheme (Last_Stm))
4117 or else Has_Exit (Entity (Identifier (Last_Stm)))
4121 -- A loop with no exit statement or iteration scheme if either
4122 -- an inifite loop, or it has some other exit (raise/return).
4123 -- In either case, no warning is required.
4129 -- Timed entry call, check entry call and delay alternatives
4131 -- Note: in expanded code, the timed entry call has been converted
4132 -- to a set of expanded statements on which the check will work
4133 -- correctly in any case.
4135 elsif Kind = N_Timed_Entry_Call then
4137 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4138 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
4141 -- If statement sequence of entry call alternative is missing,
4142 -- then we can definitely fall through, and we post the error
4143 -- message on the entry call alternative itself.
4145 if No (Statements (ECA)) then
4148 -- If statement sequence of delay alternative is missing, then
4149 -- we can definitely fall through, and we post the error
4150 -- message on the delay alternative itself.
4152 -- Note: if both ECA and DCA are missing the return, then we
4153 -- post only one message, should be enough to fix the bugs.
4154 -- If not we will get a message next time on the DCA when the
4157 elsif No (Statements (DCA)) then
4160 -- Else check both statement sequences
4163 Check_Statement_Sequence (Statements (ECA));
4164 Check_Statement_Sequence (Statements (DCA));
4169 -- Conditional entry call, check entry call and else part
4171 -- Note: in expanded code, the conditional entry call has been
4172 -- converted to a set of expanded statements on which the check
4173 -- will work correctly in any case.
4175 elsif Kind = N_Conditional_Entry_Call then
4177 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4180 -- If statement sequence of entry call alternative is missing,
4181 -- then we can definitely fall through, and we post the error
4182 -- message on the entry call alternative itself.
4184 if No (Statements (ECA)) then
4187 -- Else check statement sequence and else part
4190 Check_Statement_Sequence (Statements (ECA));
4191 Check_Statement_Sequence (Else_Statements (Last_Stm));
4197 -- If we fall through, issue appropriate message
4200 if not Raise_Exception_Call then
4202 ("?RETURN statement missing following this statement!",
4205 ("\?Program_Error may be raised at run time!",
4209 -- Note: we set Err even though we have not issued a warning
4210 -- because we still have a case of a missing return. This is
4211 -- an extremely marginal case, probably will never be noticed
4212 -- but we might as well get it right.
4216 -- Otherwise we have the case of a procedure marked No_Return
4220 ("?implied return after this statement will raise Program_Error",
4223 ("?procedure & is marked as No_Return",
4227 RE : constant Node_Id :=
4228 Make_Raise_Program_Error (Sloc (Last_Stm),
4229 Reason => PE_Implicit_Return);
4231 Insert_After (Last_Stm, RE);
4235 end Check_Statement_Sequence;
4237 -- Start of processing for Check_Returns
4241 Check_Statement_Sequence (Statements (HSS));
4243 if Present (Exception_Handlers (HSS)) then
4244 Handler := First_Non_Pragma (Exception_Handlers (HSS));
4245 while Present (Handler) loop
4246 Check_Statement_Sequence (Statements (Handler));
4247 Next_Non_Pragma (Handler);
4252 ----------------------------
4253 -- Check_Subprogram_Order --
4254 ----------------------------
4256 procedure Check_Subprogram_Order (N : Node_Id) is
4258 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
4259 -- This is used to check if S1 > S2 in the sense required by this
4260 -- test, for example nameab < namec, but name2 < name10.
4262 -----------------------------
4263 -- Subprogram_Name_Greater --
4264 -----------------------------
4266 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
4271 -- Remove trailing numeric parts
4274 while S1 (L1) in '0' .. '9' loop
4279 while S2 (L2) in '0' .. '9' loop
4283 -- If non-numeric parts non-equal, that's decisive
4285 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
4288 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
4291 -- If non-numeric parts equal, compare suffixed numeric parts. Note
4292 -- that a missing suffix is treated as numeric zero in this test.
4296 while L1 < S1'Last loop
4298 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
4302 while L2 < S2'Last loop
4304 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
4309 end Subprogram_Name_Greater;
4311 -- Start of processing for Check_Subprogram_Order
4314 -- Check body in alpha order if this is option
4317 and then Style_Check_Order_Subprograms
4318 and then Nkind (N) = N_Subprogram_Body
4319 and then Comes_From_Source (N)
4320 and then In_Extended_Main_Source_Unit (N)
4324 renames Scope_Stack.Table
4325 (Scope_Stack.Last).Last_Subprogram_Name;
4327 Body_Id : constant Entity_Id :=
4328 Defining_Entity (Specification (N));
4331 Get_Decoded_Name_String (Chars (Body_Id));
4334 if Subprogram_Name_Greater
4335 (LSN.all, Name_Buffer (1 .. Name_Len))
4337 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
4343 LSN := new String'(Name_Buffer (1 .. Name_Len));
4346 end Check_Subprogram_Order;
4348 ------------------------------
4349 -- Check_Subtype_Conformant --
4350 ------------------------------
4352 procedure Check_Subtype_Conformant
4353 (New_Id : Entity_Id;
4355 Err_Loc : Node_Id := Empty)
4360 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc);
4361 end Check_Subtype_Conformant;
4363 ---------------------------
4364 -- Check_Type_Conformant --
4365 ---------------------------
4367 procedure Check_Type_Conformant
4368 (New_Id : Entity_Id;
4370 Err_Loc : Node_Id := Empty)
4375 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
4376 end Check_Type_Conformant;
4378 ----------------------
4379 -- Conforming_Types --
4380 ----------------------
4382 function Conforming_Types
4385 Ctype : Conformance_Type;
4386 Get_Inst : Boolean := False) return Boolean
4388 Type_1 : Entity_Id := T1;
4389 Type_2 : Entity_Id := T2;
4390 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
4392 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
4393 -- If neither T1 nor T2 are generic actual types, or if they are in
4394 -- different scopes (e.g. parent and child instances), then verify that
4395 -- the base types are equal. Otherwise T1 and T2 must be on the same
4396 -- subtype chain. The whole purpose of this procedure is to prevent
4397 -- spurious ambiguities in an instantiation that may arise if two
4398 -- distinct generic types are instantiated with the same actual.
4400 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
4401 -- An access parameter can designate an incomplete type. If the
4402 -- incomplete type is the limited view of a type from a limited_
4403 -- with_clause, check whether the non-limited view is available. If
4404 -- it is a (non-limited) incomplete type, get the full view.
4406 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
4407 -- Returns True if and only if either T1 denotes a limited view of T2
4408 -- or T2 denotes a limited view of T1. This can arise when the limited
4409 -- with view of a type is used in a subprogram declaration and the
4410 -- subprogram body is in the scope of a regular with clause for the
4411 -- same unit. In such a case, the two type entities can be considered
4412 -- identical for purposes of conformance checking.
4414 ----------------------
4415 -- Base_Types_Match --
4416 ----------------------
4418 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
4423 elsif Base_Type (T1) = Base_Type (T2) then
4425 -- The following is too permissive. A more precise test should
4426 -- check that the generic actual is an ancestor subtype of the
4429 return not Is_Generic_Actual_Type (T1)
4430 or else not Is_Generic_Actual_Type (T2)
4431 or else Scope (T1) /= Scope (T2);
4436 end Base_Types_Match;
4438 --------------------------
4439 -- Find_Designated_Type --
4440 --------------------------
4442 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
4446 Desig := Directly_Designated_Type (T);
4448 if Ekind (Desig) = E_Incomplete_Type then
4450 -- If regular incomplete type, get full view if available
4452 if Present (Full_View (Desig)) then
4453 Desig := Full_View (Desig);
4455 -- If limited view of a type, get non-limited view if available,
4456 -- and check again for a regular incomplete type.
4458 elsif Present (Non_Limited_View (Desig)) then
4459 Desig := Get_Full_View (Non_Limited_View (Desig));
4464 end Find_Designated_Type;
4466 -------------------------------
4467 -- Matches_Limited_With_View --
4468 -------------------------------
4470 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
4472 -- In some cases a type imported through a limited_with clause, and
4473 -- its nonlimited view are both visible, for example in an anonymous
4474 -- access-to-class-wide type in a formal. Both entities designate the
4477 if From_With_Type (T1)
4478 and then T2 = Available_View (T1)
4482 elsif From_With_Type (T2)
4483 and then T1 = Available_View (T2)
4490 end Matches_Limited_With_View;
4492 -- Start of processing for Conforming_Types
4495 -- The context is an instance association for a formal
4496 -- access-to-subprogram type; the formal parameter types require
4497 -- mapping because they may denote other formal parameters of the
4501 Type_1 := Get_Instance_Of (T1);
4502 Type_2 := Get_Instance_Of (T2);
4505 -- If one of the types is a view of the other introduced by a limited
4506 -- with clause, treat these as conforming for all purposes.
4508 if Matches_Limited_With_View (T1, T2) then
4511 elsif Base_Types_Match (Type_1, Type_2) then
4512 return Ctype <= Mode_Conformant
4513 or else Subtypes_Statically_Match (Type_1, Type_2);
4515 elsif Is_Incomplete_Or_Private_Type (Type_1)
4516 and then Present (Full_View (Type_1))
4517 and then Base_Types_Match (Full_View (Type_1), Type_2)
4519 return Ctype <= Mode_Conformant
4520 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
4522 elsif Ekind (Type_2) = E_Incomplete_Type
4523 and then Present (Full_View (Type_2))
4524 and then Base_Types_Match (Type_1, Full_View (Type_2))
4526 return Ctype <= Mode_Conformant
4527 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4529 elsif Is_Private_Type (Type_2)
4530 and then In_Instance
4531 and then Present (Full_View (Type_2))
4532 and then Base_Types_Match (Type_1, Full_View (Type_2))
4534 return Ctype <= Mode_Conformant
4535 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4538 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
4539 -- treated recursively because they carry a signature.
4541 Are_Anonymous_Access_To_Subprogram_Types :=
4542 Ekind (Type_1) = Ekind (Type_2)
4544 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
4546 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
4548 -- Test anonymous access type case. For this case, static subtype
4549 -- matching is required for mode conformance (RM 6.3.1(15)). We check
4550 -- the base types because we may have built internal subtype entities
4551 -- to handle null-excluding types (see Process_Formals).
4553 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
4555 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
4556 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
4559 Desig_1 : Entity_Id;
4560 Desig_2 : Entity_Id;
4563 -- In Ada2005, access constant indicators must match for
4564 -- subtype conformance.
4566 if Ada_Version >= Ada_05
4567 and then Ctype >= Subtype_Conformant
4569 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
4574 Desig_1 := Find_Designated_Type (Type_1);
4576 Desig_2 := Find_Designated_Type (Type_2);
4578 -- If the context is an instance association for a formal
4579 -- access-to-subprogram type; formal access parameter designated
4580 -- types require mapping because they may denote other formal
4581 -- parameters of the generic unit.
4584 Desig_1 := Get_Instance_Of (Desig_1);
4585 Desig_2 := Get_Instance_Of (Desig_2);
4588 -- It is possible for a Class_Wide_Type to be introduced for an
4589 -- incomplete type, in which case there is a separate class_ wide
4590 -- type for the full view. The types conform if their Etypes
4591 -- conform, i.e. one may be the full view of the other. This can
4592 -- only happen in the context of an access parameter, other uses
4593 -- of an incomplete Class_Wide_Type are illegal.
4595 if Is_Class_Wide_Type (Desig_1)
4596 and then Is_Class_Wide_Type (Desig_2)
4600 (Etype (Base_Type (Desig_1)),
4601 Etype (Base_Type (Desig_2)), Ctype);
4603 elsif Are_Anonymous_Access_To_Subprogram_Types then
4604 if Ada_Version < Ada_05 then
4605 return Ctype = Type_Conformant
4607 Subtypes_Statically_Match (Desig_1, Desig_2);
4609 -- We must check the conformance of the signatures themselves
4613 Conformant : Boolean;
4616 (Desig_1, Desig_2, Ctype, False, Conformant);
4622 return Base_Type (Desig_1) = Base_Type (Desig_2)
4623 and then (Ctype = Type_Conformant
4625 Subtypes_Statically_Match (Desig_1, Desig_2));
4629 -- Otherwise definitely no match
4632 if ((Ekind (Type_1) = E_Anonymous_Access_Type
4633 and then Is_Access_Type (Type_2))
4634 or else (Ekind (Type_2) = E_Anonymous_Access_Type
4635 and then Is_Access_Type (Type_1)))
4638 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
4640 May_Hide_Profile := True;
4645 end Conforming_Types;
4647 --------------------------
4648 -- Create_Extra_Formals --
4649 --------------------------
4651 procedure Create_Extra_Formals (E : Entity_Id) is
4653 First_Extra : Entity_Id := Empty;
4654 Last_Extra : Entity_Id;
4655 Formal_Type : Entity_Id;
4656 P_Formal : Entity_Id := Empty;
4658 function Add_Extra_Formal
4659 (Assoc_Entity : Entity_Id;
4662 Suffix : String) return Entity_Id;
4663 -- Add an extra formal to the current list of formals and extra formals.
4664 -- The extra formal is added to the end of the list of extra formals,
4665 -- and also returned as the result. These formals are always of mode IN.
4666 -- The new formal has the type Typ, is declared in Scope, and its name
4667 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
4669 ----------------------
4670 -- Add_Extra_Formal --
4671 ----------------------
4673 function Add_Extra_Formal
4674 (Assoc_Entity : Entity_Id;
4677 Suffix : String) return Entity_Id
4679 EF : constant Entity_Id :=
4680 Make_Defining_Identifier (Sloc (Assoc_Entity),
4681 Chars => New_External_Name (Chars (Assoc_Entity),
4685 -- A little optimization. Never generate an extra formal for the
4686 -- _init operand of an initialization procedure, since it could
4689 if Chars (Formal) = Name_uInit then
4693 Set_Ekind (EF, E_In_Parameter);
4694 Set_Actual_Subtype (EF, Typ);
4695 Set_Etype (EF, Typ);
4696 Set_Scope (EF, Scope);
4697 Set_Mechanism (EF, Default_Mechanism);
4698 Set_Formal_Validity (EF);
4700 if No (First_Extra) then
4702 Set_Extra_Formals (Scope, First_Extra);
4705 if Present (Last_Extra) then
4706 Set_Extra_Formal (Last_Extra, EF);
4712 end Add_Extra_Formal;
4714 -- Start of processing for Create_Extra_Formals
4717 -- We never generate extra formals if expansion is not active
4718 -- because we don't need them unless we are generating code.
4720 if not Expander_Active then
4724 -- If this is a derived subprogram then the subtypes of the parent
4725 -- subprogram's formal parameters will be used to to determine the need
4726 -- for extra formals.
4728 if Is_Overloadable (E) and then Present (Alias (E)) then
4729 P_Formal := First_Formal (Alias (E));
4732 Last_Extra := Empty;
4733 Formal := First_Formal (E);
4734 while Present (Formal) loop
4735 Last_Extra := Formal;
4736 Next_Formal (Formal);
4739 -- If Extra_formals were already created, don't do it again. This
4740 -- situation may arise for subprogram types created as part of
4741 -- dispatching calls (see Expand_Dispatching_Call)
4743 if Present (Last_Extra) and then
4744 Present (Extra_Formal (Last_Extra))
4749 -- If the subprogram is a predefined dispatching subprogram then don't
4750 -- generate any extra constrained or accessibility level formals. In
4751 -- general we suppress these for internal subprograms (by not calling
4752 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
4753 -- generated stream attributes do get passed through because extra
4754 -- build-in-place formals are needed in some cases (limited 'Input).
4756 if Is_Predefined_Dispatching_Operation (E) then
4757 goto Test_For_BIP_Extras;
4760 Formal := First_Formal (E);
4761 while Present (Formal) loop
4763 -- Create extra formal for supporting the attribute 'Constrained.
4764 -- The case of a private type view without discriminants also
4765 -- requires the extra formal if the underlying type has defaulted
4768 if Ekind (Formal) /= E_In_Parameter then
4769 if Present (P_Formal) then
4770 Formal_Type := Etype (P_Formal);
4772 Formal_Type := Etype (Formal);
4775 -- Do not produce extra formals for Unchecked_Union parameters.
4776 -- Jump directly to the end of the loop.
4778 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
4779 goto Skip_Extra_Formal_Generation;
4782 if not Has_Discriminants (Formal_Type)
4783 and then Ekind (Formal_Type) in Private_Kind
4784 and then Present (Underlying_Type (Formal_Type))
4786 Formal_Type := Underlying_Type (Formal_Type);
4789 if Has_Discriminants (Formal_Type)
4790 and then not Is_Constrained (Formal_Type)
4791 and then not Is_Indefinite_Subtype (Formal_Type)
4793 Set_Extra_Constrained
4794 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "F"));
4798 -- Create extra formal for supporting accessibility checking. This
4799 -- is done for both anonymous access formals and formals of named
4800 -- access types that are marked as controlling formals. The latter
4801 -- case can occur when Expand_Dispatching_Call creates a subprogram
4802 -- type and substitutes the types of access-to-class-wide actuals
4803 -- for the anonymous access-to-specific-type of controlling formals.
4804 -- Base_Type is applied because in cases where there is a null
4805 -- exclusion the formal may have an access subtype.
4807 -- This is suppressed if we specifically suppress accessibility
4808 -- checks at the package level for either the subprogram, or the
4809 -- package in which it resides. However, we do not suppress it
4810 -- simply if the scope has accessibility checks suppressed, since
4811 -- this could cause trouble when clients are compiled with a
4812 -- different suppression setting. The explicit checks at the
4813 -- package level are safe from this point of view.
4815 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
4816 or else (Is_Controlling_Formal (Formal)
4817 and then Is_Access_Type (Base_Type (Etype (Formal)))))
4819 (Explicit_Suppress (E, Accessibility_Check)
4821 Explicit_Suppress (Scope (E), Accessibility_Check))
4824 or else Present (Extra_Accessibility (P_Formal)))
4826 -- Temporary kludge: for now we avoid creating the extra formal
4827 -- for access parameters of protected operations because of
4828 -- problem with the case of internal protected calls. ???
4830 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
4831 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
4833 Set_Extra_Accessibility
4834 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "F"));
4838 -- This label is required when skipping extra formal generation for
4839 -- Unchecked_Union parameters.
4841 <<Skip_Extra_Formal_Generation>>
4843 if Present (P_Formal) then
4844 Next_Formal (P_Formal);
4847 Next_Formal (Formal);
4850 <<Test_For_BIP_Extras>>
4852 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
4853 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
4855 if Ada_Version >= Ada_05 and then Is_Build_In_Place_Function (E) then
4857 Result_Subt : constant Entity_Id := Etype (E);
4859 Discard : Entity_Id;
4860 pragma Warnings (Off, Discard);
4863 -- In the case of functions with unconstrained result subtypes,
4864 -- add a 3-state formal indicating whether the return object is
4865 -- allocated by the caller (0), or should be allocated by the
4866 -- callee on the secondary stack (1) or in the global heap (2).
4867 -- For the moment we just use Natural for the type of this formal.
4868 -- Note that this formal isn't usually needed in the case where
4869 -- the result subtype is constrained, but it is needed when the
4870 -- function has a tagged result, because generally such functions
4871 -- can be called in a dispatching context and such calls must be
4872 -- handled like calls to a class-wide function.
4874 if not Is_Constrained (Result_Subt)
4875 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
4879 (E, Standard_Natural,
4880 E, BIP_Formal_Suffix (BIP_Alloc_Form));
4883 -- In the case of functions whose result type has controlled
4884 -- parts, we have an extra formal of type
4885 -- System.Finalization_Implementation.Finalizable_Ptr_Ptr. That
4886 -- is, we are passing a pointer to a finalization list (which is
4887 -- itself a pointer). This extra formal is then passed along to
4888 -- Move_Final_List in case of successful completion of a return
4889 -- statement. We cannot pass an 'in out' parameter, because we
4890 -- need to update the finalization list during an abort-deferred
4891 -- region, rather than using copy-back after the function
4892 -- returns. This is true even if we are able to get away with
4893 -- having 'in out' parameters, which are normally illegal for
4894 -- functions. This formal is also needed when the function has
4895 -- a tagged result, because generally such functions can be called
4896 -- in a dispatching context and such calls must be handled like
4897 -- calls to class-wide functions.
4899 if Controlled_Type (Result_Subt)
4900 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
4904 (E, RTE (RE_Finalizable_Ptr_Ptr),
4905 E, BIP_Formal_Suffix (BIP_Final_List));
4908 -- If the result type contains tasks, we have two extra formals:
4909 -- the master of the tasks to be created, and the caller's
4910 -- activation chain.
4912 if Has_Task (Result_Subt) then
4915 (E, RTE (RE_Master_Id),
4916 E, BIP_Formal_Suffix (BIP_Master));
4919 (E, RTE (RE_Activation_Chain_Access),
4920 E, BIP_Formal_Suffix (BIP_Activation_Chain));
4923 -- All build-in-place functions get an extra formal that will be
4924 -- passed the address of the return object within the caller.
4927 Formal_Type : constant Entity_Id :=
4929 (E_Anonymous_Access_Type, E,
4930 Scope_Id => Scope (E));
4932 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
4933 Set_Etype (Formal_Type, Formal_Type);
4934 Init_Size_Align (Formal_Type);
4935 Set_Depends_On_Private
4936 (Formal_Type, Has_Private_Component (Formal_Type));
4937 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
4938 Set_Is_Access_Constant (Formal_Type, False);
4940 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
4941 -- the designated type comes from the limited view (for
4942 -- back-end purposes).
4944 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
4946 Layout_Type (Formal_Type);
4950 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
4954 end Create_Extra_Formals;
4956 -----------------------------
4957 -- Enter_Overloaded_Entity --
4958 -----------------------------
4960 procedure Enter_Overloaded_Entity (S : Entity_Id) is
4961 E : Entity_Id := Current_Entity_In_Scope (S);
4962 C_E : Entity_Id := Current_Entity (S);
4966 Set_Has_Homonym (E);
4967 Set_Has_Homonym (S);
4970 Set_Is_Immediately_Visible (S);
4971 Set_Scope (S, Current_Scope);
4973 -- Chain new entity if front of homonym in current scope, so that
4974 -- homonyms are contiguous.
4979 while Homonym (C_E) /= E loop
4980 C_E := Homonym (C_E);
4983 Set_Homonym (C_E, S);
4987 Set_Current_Entity (S);
4992 Append_Entity (S, Current_Scope);
4993 Set_Public_Status (S);
4995 if Debug_Flag_E then
4996 Write_Str ("New overloaded entity chain: ");
4997 Write_Name (Chars (S));
5000 while Present (E) loop
5001 Write_Str (" "); Write_Int (Int (E));
5008 -- Generate warning for hiding
5011 and then Comes_From_Source (S)
5012 and then In_Extended_Main_Source_Unit (S)
5019 -- Warn unless genuine overloading
5021 if (not Is_Overloadable (E) or else Subtype_Conformant (E, S))
5022 and then (Is_Immediately_Visible (E)
5024 Is_Potentially_Use_Visible (S))
5026 Error_Msg_Sloc := Sloc (E);
5027 Error_Msg_N ("declaration of & hides one#?", S);
5031 end Enter_Overloaded_Entity;
5033 -----------------------------
5034 -- Find_Corresponding_Spec --
5035 -----------------------------
5037 function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is
5038 Spec : constant Node_Id := Specification (N);
5039 Designator : constant Entity_Id := Defining_Entity (Spec);
5044 E := Current_Entity (Designator);
5045 while Present (E) loop
5047 -- We are looking for a matching spec. It must have the same scope,
5048 -- and the same name, and either be type conformant, or be the case
5049 -- of a library procedure spec and its body (which belong to one
5050 -- another regardless of whether they are type conformant or not).
5052 if Scope (E) = Current_Scope then
5053 if Current_Scope = Standard_Standard
5054 or else (Ekind (E) = Ekind (Designator)
5055 and then Type_Conformant (E, Designator))
5057 -- Within an instantiation, we know that spec and body are
5058 -- subtype conformant, because they were subtype conformant
5059 -- in the generic. We choose the subtype-conformant entity
5060 -- here as well, to resolve spurious ambiguities in the
5061 -- instance that were not present in the generic (i.e. when
5062 -- two different types are given the same actual). If we are
5063 -- looking for a spec to match a body, full conformance is
5067 Set_Convention (Designator, Convention (E));
5069 if Nkind (N) = N_Subprogram_Body
5070 and then Present (Homonym (E))
5071 and then not Fully_Conformant (E, Designator)
5075 elsif not Subtype_Conformant (E, Designator) then
5080 if not Has_Completion (E) then
5082 if Nkind (N) /= N_Subprogram_Body_Stub then
5083 Set_Corresponding_Spec (N, E);
5086 Set_Has_Completion (E);
5089 elsif Nkind (Parent (N)) = N_Subunit then
5091 -- If this is the proper body of a subunit, the completion
5092 -- flag is set when analyzing the stub.
5096 -- If body already exists, this is an error unless the
5097 -- previous declaration is the implicit declaration of
5098 -- a derived subprogram, or this is a spurious overloading
5101 elsif No (Alias (E))
5102 and then not Is_Intrinsic_Subprogram (E)
5103 and then not In_Instance
5105 Error_Msg_Sloc := Sloc (E);
5106 if Is_Imported (E) then
5108 ("body not allowed for imported subprogram & declared#",
5111 Error_Msg_NE ("duplicate body for & declared#", N, E);
5115 elsif Is_Child_Unit (E)
5117 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
5119 Nkind (Parent (Unit_Declaration_Node (Designator))) =
5122 -- Child units cannot be overloaded, so a conformance mismatch
5123 -- between body and a previous spec is an error.
5126 ("body of child unit does not match previous declaration", N);
5134 -- On exit, we know that no previous declaration of subprogram exists
5137 end Find_Corresponding_Spec;
5139 ----------------------
5140 -- Fully_Conformant --
5141 ----------------------
5143 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5146 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
5148 end Fully_Conformant;
5150 ----------------------------------
5151 -- Fully_Conformant_Expressions --
5152 ----------------------------------
5154 function Fully_Conformant_Expressions
5155 (Given_E1 : Node_Id;
5156 Given_E2 : Node_Id) return Boolean
5158 E1 : constant Node_Id := Original_Node (Given_E1);
5159 E2 : constant Node_Id := Original_Node (Given_E2);
5160 -- We always test conformance on original nodes, since it is possible
5161 -- for analysis and/or expansion to make things look as though they
5162 -- conform when they do not, e.g. by converting 1+2 into 3.
5164 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
5165 renames Fully_Conformant_Expressions;
5167 function FCL (L1, L2 : List_Id) return Boolean;
5168 -- Compare elements of two lists for conformance. Elements have to
5169 -- be conformant, and actuals inserted as default parameters do not
5170 -- match explicit actuals with the same value.
5172 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
5173 -- Compare an operator node with a function call
5179 function FCL (L1, L2 : List_Id) return Boolean is
5183 if L1 = No_List then
5189 if L2 = No_List then
5195 -- Compare two lists, skipping rewrite insertions (we want to
5196 -- compare the original trees, not the expanded versions!)
5199 if Is_Rewrite_Insertion (N1) then
5201 elsif Is_Rewrite_Insertion (N2) then
5207 elsif not FCE (N1, N2) then
5220 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
5221 Actuals : constant List_Id := Parameter_Associations (Call_Node);
5226 or else Entity (Op_Node) /= Entity (Name (Call_Node))
5231 Act := First (Actuals);
5233 if Nkind (Op_Node) in N_Binary_Op then
5235 if not FCE (Left_Opnd (Op_Node), Act) then
5242 return Present (Act)
5243 and then FCE (Right_Opnd (Op_Node), Act)
5244 and then No (Next (Act));
5248 -- Start of processing for Fully_Conformant_Expressions
5251 -- Non-conformant if paren count does not match. Note: if some idiot
5252 -- complains that we don't do this right for more than 3 levels of
5253 -- parentheses, they will be treated with the respect they deserve!
5255 if Paren_Count (E1) /= Paren_Count (E2) then
5258 -- If same entities are referenced, then they are conformant even if
5259 -- they have different forms (RM 8.3.1(19-20)).
5261 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
5262 if Present (Entity (E1)) then
5263 return Entity (E1) = Entity (E2)
5264 or else (Chars (Entity (E1)) = Chars (Entity (E2))
5265 and then Ekind (Entity (E1)) = E_Discriminant
5266 and then Ekind (Entity (E2)) = E_In_Parameter);
5268 elsif Nkind (E1) = N_Expanded_Name
5269 and then Nkind (E2) = N_Expanded_Name
5270 and then Nkind (Selector_Name (E1)) = N_Character_Literal
5271 and then Nkind (Selector_Name (E2)) = N_Character_Literal
5273 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
5276 -- Identifiers in component associations don't always have
5277 -- entities, but their names must conform.
5279 return Nkind (E1) = N_Identifier
5280 and then Nkind (E2) = N_Identifier
5281 and then Chars (E1) = Chars (E2);
5284 elsif Nkind (E1) = N_Character_Literal
5285 and then Nkind (E2) = N_Expanded_Name
5287 return Nkind (Selector_Name (E2)) = N_Character_Literal
5288 and then Chars (E1) = Chars (Selector_Name (E2));
5290 elsif Nkind (E2) = N_Character_Literal
5291 and then Nkind (E1) = N_Expanded_Name
5293 return Nkind (Selector_Name (E1)) = N_Character_Literal
5294 and then Chars (E2) = Chars (Selector_Name (E1));
5296 elsif Nkind (E1) in N_Op
5297 and then Nkind (E2) = N_Function_Call
5299 return FCO (E1, E2);
5301 elsif Nkind (E2) in N_Op
5302 and then Nkind (E1) = N_Function_Call
5304 return FCO (E2, E1);
5306 -- Otherwise we must have the same syntactic entity
5308 elsif Nkind (E1) /= Nkind (E2) then
5311 -- At this point, we specialize by node type
5318 FCL (Expressions (E1), Expressions (E2))
5319 and then FCL (Component_Associations (E1),
5320 Component_Associations (E2));
5323 if Nkind (Expression (E1)) = N_Qualified_Expression
5325 Nkind (Expression (E2)) = N_Qualified_Expression
5327 return FCE (Expression (E1), Expression (E2));
5329 -- Check that the subtype marks and any constraints
5334 Indic1 : constant Node_Id := Expression (E1);
5335 Indic2 : constant Node_Id := Expression (E2);
5340 if Nkind (Indic1) /= N_Subtype_Indication then
5342 Nkind (Indic2) /= N_Subtype_Indication
5343 and then Entity (Indic1) = Entity (Indic2);
5345 elsif Nkind (Indic2) /= N_Subtype_Indication then
5347 Nkind (Indic1) /= N_Subtype_Indication
5348 and then Entity (Indic1) = Entity (Indic2);
5351 if Entity (Subtype_Mark (Indic1)) /=
5352 Entity (Subtype_Mark (Indic2))
5357 Elt1 := First (Constraints (Constraint (Indic1)));
5358 Elt2 := First (Constraints (Constraint (Indic2)));
5360 while Present (Elt1) and then Present (Elt2) loop
5361 if not FCE (Elt1, Elt2) then
5374 when N_Attribute_Reference =>
5376 Attribute_Name (E1) = Attribute_Name (E2)
5377 and then FCL (Expressions (E1), Expressions (E2));
5381 Entity (E1) = Entity (E2)
5382 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
5383 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5385 when N_And_Then | N_Or_Else | N_Membership_Test =>
5387 FCE (Left_Opnd (E1), Left_Opnd (E2))
5389 FCE (Right_Opnd (E1), Right_Opnd (E2));
5391 when N_Character_Literal =>
5393 Char_Literal_Value (E1) = Char_Literal_Value (E2);
5395 when N_Component_Association =>
5397 FCL (Choices (E1), Choices (E2))
5398 and then FCE (Expression (E1), Expression (E2));
5400 when N_Conditional_Expression =>
5402 FCL (Expressions (E1), Expressions (E2));
5404 when N_Explicit_Dereference =>
5406 FCE (Prefix (E1), Prefix (E2));
5408 when N_Extension_Aggregate =>
5410 FCL (Expressions (E1), Expressions (E2))
5411 and then Null_Record_Present (E1) =
5412 Null_Record_Present (E2)
5413 and then FCL (Component_Associations (E1),
5414 Component_Associations (E2));
5416 when N_Function_Call =>
5418 FCE (Name (E1), Name (E2))
5419 and then FCL (Parameter_Associations (E1),
5420 Parameter_Associations (E2));
5422 when N_Indexed_Component =>
5424 FCE (Prefix (E1), Prefix (E2))
5425 and then FCL (Expressions (E1), Expressions (E2));
5427 when N_Integer_Literal =>
5428 return (Intval (E1) = Intval (E2));
5433 when N_Operator_Symbol =>
5435 Chars (E1) = Chars (E2);
5437 when N_Others_Choice =>
5440 when N_Parameter_Association =>
5442 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
5443 and then FCE (Explicit_Actual_Parameter (E1),
5444 Explicit_Actual_Parameter (E2));
5446 when N_Qualified_Expression =>
5448 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5449 and then FCE (Expression (E1), Expression (E2));
5453 FCE (Low_Bound (E1), Low_Bound (E2))
5454 and then FCE (High_Bound (E1), High_Bound (E2));
5456 when N_Real_Literal =>
5457 return (Realval (E1) = Realval (E2));
5459 when N_Selected_Component =>
5461 FCE (Prefix (E1), Prefix (E2))
5462 and then FCE (Selector_Name (E1), Selector_Name (E2));
5466 FCE (Prefix (E1), Prefix (E2))
5467 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
5469 when N_String_Literal =>
5471 S1 : constant String_Id := Strval (E1);
5472 S2 : constant String_Id := Strval (E2);
5473 L1 : constant Nat := String_Length (S1);
5474 L2 : constant Nat := String_Length (S2);
5481 for J in 1 .. L1 loop
5482 if Get_String_Char (S1, J) /=
5483 Get_String_Char (S2, J)
5493 when N_Type_Conversion =>
5495 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5496 and then FCE (Expression (E1), Expression (E2));
5500 Entity (E1) = Entity (E2)
5501 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5503 when N_Unchecked_Type_Conversion =>
5505 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5506 and then FCE (Expression (E1), Expression (E2));
5508 -- All other node types cannot appear in this context. Strictly
5509 -- we should raise a fatal internal error. Instead we just ignore
5510 -- the nodes. This means that if anyone makes a mistake in the
5511 -- expander and mucks an expression tree irretrievably, the
5512 -- result will be a failure to detect a (probably very obscure)
5513 -- case of non-conformance, which is better than bombing on some
5514 -- case where two expressions do in fact conform.
5521 end Fully_Conformant_Expressions;
5523 ----------------------------------------
5524 -- Fully_Conformant_Discrete_Subtypes --
5525 ----------------------------------------
5527 function Fully_Conformant_Discrete_Subtypes
5528 (Given_S1 : Node_Id;
5529 Given_S2 : Node_Id) return Boolean
5531 S1 : constant Node_Id := Original_Node (Given_S1);
5532 S2 : constant Node_Id := Original_Node (Given_S2);
5534 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
5535 -- Special-case for a bound given by a discriminant, which in the body
5536 -- is replaced with the discriminal of the enclosing type.
5538 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
5539 -- Check both bounds
5541 -----------------------
5542 -- Conforming_Bounds --
5543 -----------------------
5545 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
5547 if Is_Entity_Name (B1)
5548 and then Is_Entity_Name (B2)
5549 and then Ekind (Entity (B1)) = E_Discriminant
5551 return Chars (B1) = Chars (B2);
5554 return Fully_Conformant_Expressions (B1, B2);
5556 end Conforming_Bounds;
5558 -----------------------
5559 -- Conforming_Ranges --
5560 -----------------------
5562 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
5565 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
5567 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
5568 end Conforming_Ranges;
5570 -- Start of processing for Fully_Conformant_Discrete_Subtypes
5573 if Nkind (S1) /= Nkind (S2) then
5576 elsif Is_Entity_Name (S1) then
5577 return Entity (S1) = Entity (S2);
5579 elsif Nkind (S1) = N_Range then
5580 return Conforming_Ranges (S1, S2);
5582 elsif Nkind (S1) = N_Subtype_Indication then
5584 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
5587 (Range_Expression (Constraint (S1)),
5588 Range_Expression (Constraint (S2)));
5592 end Fully_Conformant_Discrete_Subtypes;
5594 --------------------
5595 -- Install_Entity --
5596 --------------------
5598 procedure Install_Entity (E : Entity_Id) is
5599 Prev : constant Entity_Id := Current_Entity (E);
5601 Set_Is_Immediately_Visible (E);
5602 Set_Current_Entity (E);
5603 Set_Homonym (E, Prev);
5606 ---------------------
5607 -- Install_Formals --
5608 ---------------------
5610 procedure Install_Formals (Id : Entity_Id) is
5613 F := First_Formal (Id);
5614 while Present (F) loop
5618 end Install_Formals;
5620 ---------------------------------
5621 -- Is_Non_Overriding_Operation --
5622 ---------------------------------
5624 function Is_Non_Overriding_Operation
5625 (Prev_E : Entity_Id;
5626 New_E : Entity_Id) return Boolean
5630 G_Typ : Entity_Id := Empty;
5632 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
5633 -- If F_Type is a derived type associated with a generic actual subtype,
5634 -- then return its Generic_Parent_Type attribute, else return Empty.
5636 function Types_Correspond
5637 (P_Type : Entity_Id;
5638 N_Type : Entity_Id) return Boolean;
5639 -- Returns true if and only if the types (or designated types in the
5640 -- case of anonymous access types) are the same or N_Type is derived
5641 -- directly or indirectly from P_Type.
5643 -----------------------------
5644 -- Get_Generic_Parent_Type --
5645 -----------------------------
5647 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
5652 if Is_Derived_Type (F_Typ)
5653 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
5655 -- The tree must be traversed to determine the parent subtype in
5656 -- the generic unit, which unfortunately isn't always available
5657 -- via semantic attributes. ??? (Note: The use of Original_Node
5658 -- is needed for cases where a full derived type has been
5661 Indic := Subtype_Indication
5662 (Type_Definition (Original_Node (Parent (F_Typ))));
5664 if Nkind (Indic) = N_Subtype_Indication then
5665 G_Typ := Entity (Subtype_Mark (Indic));
5667 G_Typ := Entity (Indic);
5670 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
5671 and then Present (Generic_Parent_Type (Parent (G_Typ)))
5673 return Generic_Parent_Type (Parent (G_Typ));
5678 end Get_Generic_Parent_Type;
5680 ----------------------
5681 -- Types_Correspond --
5682 ----------------------
5684 function Types_Correspond
5685 (P_Type : Entity_Id;
5686 N_Type : Entity_Id) return Boolean
5688 Prev_Type : Entity_Id := Base_Type (P_Type);
5689 New_Type : Entity_Id := Base_Type (N_Type);
5692 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
5693 Prev_Type := Designated_Type (Prev_Type);
5696 if Ekind (New_Type) = E_Anonymous_Access_Type then
5697 New_Type := Designated_Type (New_Type);
5700 if Prev_Type = New_Type then
5703 elsif not Is_Class_Wide_Type (New_Type) then
5704 while Etype (New_Type) /= New_Type loop
5705 New_Type := Etype (New_Type);
5706 if New_Type = Prev_Type then
5712 end Types_Correspond;
5714 -- Start of processing for Is_Non_Overriding_Operation
5717 -- In the case where both operations are implicit derived subprograms
5718 -- then neither overrides the other. This can only occur in certain
5719 -- obscure cases (e.g., derivation from homographs created in a generic
5722 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
5725 elsif Ekind (Current_Scope) = E_Package
5726 and then Is_Generic_Instance (Current_Scope)
5727 and then In_Private_Part (Current_Scope)
5728 and then Comes_From_Source (New_E)
5730 -- We examine the formals and result subtype of the inherited
5731 -- operation, to determine whether their type is derived from (the
5732 -- instance of) a generic type.
5734 Formal := First_Formal (Prev_E);
5736 while Present (Formal) loop
5737 F_Typ := Base_Type (Etype (Formal));
5739 if Ekind (F_Typ) = E_Anonymous_Access_Type then
5740 F_Typ := Designated_Type (F_Typ);
5743 G_Typ := Get_Generic_Parent_Type (F_Typ);
5745 Next_Formal (Formal);
5748 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
5749 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
5756 -- If the generic type is a private type, then the original
5757 -- operation was not overriding in the generic, because there was
5758 -- no primitive operation to override.
5760 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
5761 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
5762 N_Formal_Private_Type_Definition
5766 -- The generic parent type is the ancestor of a formal derived
5767 -- type declaration. We need to check whether it has a primitive
5768 -- operation that should be overridden by New_E in the generic.
5772 P_Formal : Entity_Id;
5773 N_Formal : Entity_Id;
5777 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
5780 while Present (Prim_Elt) loop
5781 P_Prim := Node (Prim_Elt);
5783 if Chars (P_Prim) = Chars (New_E)
5784 and then Ekind (P_Prim) = Ekind (New_E)
5786 P_Formal := First_Formal (P_Prim);
5787 N_Formal := First_Formal (New_E);
5788 while Present (P_Formal) and then Present (N_Formal) loop
5789 P_Typ := Etype (P_Formal);
5790 N_Typ := Etype (N_Formal);
5792 if not Types_Correspond (P_Typ, N_Typ) then
5796 Next_Entity (P_Formal);
5797 Next_Entity (N_Formal);
5800 -- Found a matching primitive operation belonging to the
5801 -- formal ancestor type, so the new subprogram is
5805 and then No (N_Formal)
5806 and then (Ekind (New_E) /= E_Function
5809 (Etype (P_Prim), Etype (New_E)))
5815 Next_Elmt (Prim_Elt);
5818 -- If no match found, then the new subprogram does not
5819 -- override in the generic (nor in the instance).
5827 end Is_Non_Overriding_Operation;
5829 ------------------------------
5830 -- Make_Inequality_Operator --
5831 ------------------------------
5833 -- S is the defining identifier of an equality operator. We build a
5834 -- subprogram declaration with the right signature. This operation is
5835 -- intrinsic, because it is always expanded as the negation of the
5836 -- call to the equality function.
5838 procedure Make_Inequality_Operator (S : Entity_Id) is
5839 Loc : constant Source_Ptr := Sloc (S);
5842 Op_Name : Entity_Id;
5844 FF : constant Entity_Id := First_Formal (S);
5845 NF : constant Entity_Id := Next_Formal (FF);
5848 -- Check that equality was properly defined, ignore call if not
5855 A : constant Entity_Id :=
5856 Make_Defining_Identifier (Sloc (FF),
5857 Chars => Chars (FF));
5859 B : constant Entity_Id :=
5860 Make_Defining_Identifier (Sloc (NF),
5861 Chars => Chars (NF));
5864 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
5866 Formals := New_List (
5867 Make_Parameter_Specification (Loc,
5868 Defining_Identifier => A,
5870 New_Reference_To (Etype (First_Formal (S)),
5871 Sloc (Etype (First_Formal (S))))),
5873 Make_Parameter_Specification (Loc,
5874 Defining_Identifier => B,
5876 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
5877 Sloc (Etype (Next_Formal (First_Formal (S)))))));
5880 Make_Subprogram_Declaration (Loc,
5882 Make_Function_Specification (Loc,
5883 Defining_Unit_Name => Op_Name,
5884 Parameter_Specifications => Formals,
5885 Result_Definition =>
5886 New_Reference_To (Standard_Boolean, Loc)));
5888 -- Insert inequality right after equality if it is explicit or after
5889 -- the derived type when implicit. These entities are created only
5890 -- for visibility purposes, and eventually replaced in the course of
5891 -- expansion, so they do not need to be attached to the tree and seen
5892 -- by the back-end. Keeping them internal also avoids spurious
5893 -- freezing problems. The declaration is inserted in the tree for
5894 -- analysis, and removed afterwards. If the equality operator comes
5895 -- from an explicit declaration, attach the inequality immediately
5896 -- after. Else the equality is inherited from a derived type
5897 -- declaration, so insert inequality after that declaration.
5899 if No (Alias (S)) then
5900 Insert_After (Unit_Declaration_Node (S), Decl);
5901 elsif Is_List_Member (Parent (S)) then
5902 Insert_After (Parent (S), Decl);
5904 Insert_After (Parent (Etype (First_Formal (S))), Decl);
5907 Mark_Rewrite_Insertion (Decl);
5908 Set_Is_Intrinsic_Subprogram (Op_Name);
5911 Set_Has_Completion (Op_Name);
5912 Set_Corresponding_Equality (Op_Name, S);
5913 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
5915 end Make_Inequality_Operator;
5917 ----------------------
5918 -- May_Need_Actuals --
5919 ----------------------
5921 procedure May_Need_Actuals (Fun : Entity_Id) is
5926 F := First_Formal (Fun);
5928 while Present (F) loop
5929 if No (Default_Value (F)) then
5937 Set_Needs_No_Actuals (Fun, B);
5938 end May_Need_Actuals;
5940 ---------------------
5941 -- Mode_Conformant --
5942 ---------------------
5944 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5947 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
5949 end Mode_Conformant;
5951 ---------------------------
5952 -- New_Overloaded_Entity --
5953 ---------------------------
5955 procedure New_Overloaded_Entity
5957 Derived_Type : Entity_Id := Empty)
5959 Overridden_Subp : Entity_Id := Empty;
5960 -- Set if the current scope has an operation that is type-conformant
5961 -- with S, and becomes hidden by S.
5963 Is_Primitive_Subp : Boolean;
5964 -- Set to True if the new subprogram is primitive
5967 -- Entity that S overrides
5969 Prev_Vis : Entity_Id := Empty;
5970 -- Predecessor of E in Homonym chain
5972 procedure Check_For_Primitive_Subprogram
5973 (Is_Primitive : out Boolean;
5974 Is_Overriding : Boolean := False);
5975 -- If the subprogram being analyzed is a primitive operation of the type
5976 -- of a formal or result, set the Has_Primitive_Operations flag on the
5977 -- type, and set Is_Primitive to True (otherwise set to False). Set the
5978 -- corresponding flag on the entity itself for later use.
5980 procedure Check_Synchronized_Overriding
5981 (Def_Id : Entity_Id;
5982 First_Hom : Entity_Id;
5983 Overridden_Subp : out Entity_Id);
5984 -- First determine if Def_Id is an entry or a subprogram either defined
5985 -- in the scope of a task or protected type, or is a primitive of such
5986 -- a type. Check whether Def_Id overrides a subprogram of an interface
5987 -- implemented by the synchronized type, return the overridden entity
5990 function Is_Private_Declaration (E : Entity_Id) return Boolean;
5991 -- Check that E is declared in the private part of the current package,
5992 -- or in the package body, where it may hide a previous declaration.
5993 -- We can't use In_Private_Part by itself because this flag is also
5994 -- set when freezing entities, so we must examine the place of the
5995 -- declaration in the tree, and recognize wrapper packages as well.
5997 ------------------------------------
5998 -- Check_For_Primitive_Subprogram --
5999 ------------------------------------
6001 procedure Check_For_Primitive_Subprogram
6002 (Is_Primitive : out Boolean;
6003 Is_Overriding : Boolean := False)
6009 function Visible_Part_Type (T : Entity_Id) return Boolean;
6010 -- Returns true if T is declared in the visible part of
6011 -- the current package scope; otherwise returns false.
6012 -- Assumes that T is declared in a package.
6014 procedure Check_Private_Overriding (T : Entity_Id);
6015 -- Checks that if a primitive abstract subprogram of a visible
6016 -- abstract type is declared in a private part, then it must
6017 -- override an abstract subprogram declared in the visible part.
6018 -- Also checks that if a primitive function with a controlling
6019 -- result is declared in a private part, then it must override
6020 -- a function declared in the visible part.
6022 ------------------------------
6023 -- Check_Private_Overriding --
6024 ------------------------------
6026 procedure Check_Private_Overriding (T : Entity_Id) is
6028 if Ekind (Current_Scope) = E_Package
6029 and then In_Private_Part (Current_Scope)
6030 and then Visible_Part_Type (T)
6031 and then not In_Instance
6033 if Is_Abstract_Type (T)
6034 and then Is_Abstract_Subprogram (S)
6035 and then (not Is_Overriding
6036 or else not Is_Abstract_Subprogram (E))
6038 Error_Msg_N ("abstract subprograms must be visible "
6039 & "(RM 3.9.3(10))!", S);
6041 elsif Ekind (S) = E_Function
6042 and then Is_Tagged_Type (T)
6043 and then T = Base_Type (Etype (S))
6044 and then not Is_Overriding
6047 ("private function with tagged result must"
6048 & " override visible-part function", S);
6050 ("\move subprogram to the visible part"
6051 & " (RM 3.9.3(10))", S);
6054 end Check_Private_Overriding;
6056 -----------------------
6057 -- Visible_Part_Type --
6058 -----------------------
6060 function Visible_Part_Type (T : Entity_Id) return Boolean is
6061 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
6065 -- If the entity is a private type, then it must be
6066 -- declared in a visible part.
6068 if Ekind (T) in Private_Kind then
6072 -- Otherwise, we traverse the visible part looking for its
6073 -- corresponding declaration. We cannot use the declaration
6074 -- node directly because in the private part the entity of a
6075 -- private type is the one in the full view, which does not
6076 -- indicate that it is the completion of something visible.
6078 N := First (Visible_Declarations (Specification (P)));
6079 while Present (N) loop
6080 if Nkind (N) = N_Full_Type_Declaration
6081 and then Present (Defining_Identifier (N))
6082 and then T = Defining_Identifier (N)
6086 elsif (Nkind (N) = N_Private_Type_Declaration
6088 Nkind (N) = N_Private_Extension_Declaration)
6089 and then Present (Defining_Identifier (N))
6090 and then T = Full_View (Defining_Identifier (N))
6099 end Visible_Part_Type;
6101 -- Start of processing for Check_For_Primitive_Subprogram
6104 Is_Primitive := False;
6106 if not Comes_From_Source (S) then
6109 -- If subprogram is at library level, it is not primitive operation
6111 elsif Current_Scope = Standard_Standard then
6114 elsif ((Ekind (Current_Scope) = E_Package
6115 or else Ekind (Current_Scope) = E_Generic_Package)
6116 and then not In_Package_Body (Current_Scope))
6117 or else Is_Overriding
6119 -- For function, check return type
6121 if Ekind (S) = E_Function then
6122 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
6123 F_Typ := Designated_Type (Etype (S));
6128 B_Typ := Base_Type (F_Typ);
6130 if Scope (B_Typ) = Current_Scope
6131 and then not Is_Class_Wide_Type (B_Typ)
6132 and then not Is_Generic_Type (B_Typ)
6134 Is_Primitive := True;
6135 Set_Has_Primitive_Operations (B_Typ);
6136 Set_Is_Primitive (S);
6137 Check_Private_Overriding (B_Typ);
6141 -- For all subprograms, check formals
6143 Formal := First_Formal (S);
6144 while Present (Formal) loop
6145 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
6146 F_Typ := Designated_Type (Etype (Formal));
6148 F_Typ := Etype (Formal);
6151 B_Typ := Base_Type (F_Typ);
6153 if Ekind (B_Typ) = E_Access_Subtype then
6154 B_Typ := Base_Type (B_Typ);
6157 if Scope (B_Typ) = Current_Scope
6158 and then not Is_Class_Wide_Type (B_Typ)
6159 and then not Is_Generic_Type (B_Typ)
6161 Is_Primitive := True;
6162 Set_Is_Primitive (S);
6163 Set_Has_Primitive_Operations (B_Typ);
6164 Check_Private_Overriding (B_Typ);
6167 Next_Formal (Formal);
6170 end Check_For_Primitive_Subprogram;
6172 -----------------------------------
6173 -- Check_Synchronized_Overriding --
6174 -----------------------------------
6176 procedure Check_Synchronized_Overriding
6177 (Def_Id : Entity_Id;
6178 First_Hom : Entity_Id;
6179 Overridden_Subp : out Entity_Id)
6181 Formal_Typ : Entity_Id;
6182 Ifaces_List : Elist_Id;
6187 Overridden_Subp := Empty;
6189 -- Def_Id must be an entry or a subprogram
6191 if Ekind (Def_Id) /= E_Entry
6192 and then Ekind (Def_Id) /= E_Function
6193 and then Ekind (Def_Id) /= E_Procedure
6198 -- Search for the concurrent declaration since it contains the list
6199 -- of all implemented interfaces. In this case, the subprogram is
6200 -- declared within the scope of a protected or a task type.
6202 if Present (Scope (Def_Id))
6203 and then Is_Concurrent_Type (Scope (Def_Id))
6204 and then not Is_Generic_Actual_Type (Scope (Def_Id))
6206 Typ := Scope (Def_Id);
6209 -- The subprogram may be a primitive of a concurrent type
6211 elsif Present (First_Formal (Def_Id)) then
6212 Formal_Typ := Etype (First_Formal (Def_Id));
6214 if Is_Concurrent_Type (Formal_Typ)
6215 and then not Is_Generic_Actual_Type (Formal_Typ)
6220 -- This case occurs when the concurrent type is declared within
6221 -- a generic unit. As a result the corresponding record has been
6222 -- built and used as the type of the first formal, we just have
6223 -- to retrieve the corresponding concurrent type.
6225 elsif Is_Concurrent_Record_Type (Formal_Typ)
6226 and then Present (Corresponding_Concurrent_Type (Formal_Typ))
6228 Typ := Corresponding_Concurrent_Type (Formal_Typ);
6238 -- Gather all limited, protected and task interfaces that Typ
6239 -- implements. There is no overriding to check if is an inherited
6240 -- operation in a type derivation on for a generic actual.
6242 if Nkind (Parent (Typ)) /= N_Full_Type_Declaration
6243 and then Nkind (Parent (Def_Id)) /= N_Subtype_Declaration
6244 and then Nkind (Parent (Def_Id)) /= N_Task_Type_Declaration
6245 and then Nkind (Parent (Def_Id)) /= N_Protected_Type_Declaration
6247 Collect_Abstract_Interfaces (Typ, Ifaces_List);
6249 if not Is_Empty_Elmt_List (Ifaces_List) then
6251 Find_Overridden_Synchronized_Primitive
6252 (Def_Id, First_Hom, Ifaces_List, In_Scope);
6255 end Check_Synchronized_Overriding;
6257 ----------------------------
6258 -- Is_Private_Declaration --
6259 ----------------------------
6261 function Is_Private_Declaration (E : Entity_Id) return Boolean is
6262 Priv_Decls : List_Id;
6263 Decl : constant Node_Id := Unit_Declaration_Node (E);
6266 if Is_Package_Or_Generic_Package (Current_Scope)
6267 and then In_Private_Part (Current_Scope)
6270 Private_Declarations (
6271 Specification (Unit_Declaration_Node (Current_Scope)));
6273 return In_Package_Body (Current_Scope)
6275 (Is_List_Member (Decl)
6276 and then List_Containing (Decl) = Priv_Decls)
6277 or else (Nkind (Parent (Decl)) = N_Package_Specification
6278 and then not Is_Compilation_Unit (
6279 Defining_Entity (Parent (Decl)))
6280 and then List_Containing (Parent (Parent (Decl)))
6285 end Is_Private_Declaration;
6287 -- Start of processing for New_Overloaded_Entity
6290 -- We need to look for an entity that S may override. This must be a
6291 -- homonym in the current scope, so we look for the first homonym of
6292 -- S in the current scope as the starting point for the search.
6294 E := Current_Entity_In_Scope (S);
6296 -- If there is no homonym then this is definitely not overriding
6299 Enter_Overloaded_Entity (S);
6300 Check_Dispatching_Operation (S, Empty);
6301 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6303 -- If subprogram has an explicit declaration, check whether it
6304 -- has an overriding indicator.
6306 if Comes_From_Source (S) then
6307 Check_Synchronized_Overriding (S, Homonym (S), Overridden_Subp);
6308 Check_Overriding_Indicator
6309 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6312 -- If there is a homonym that is not overloadable, then we have an
6313 -- error, except for the special cases checked explicitly below.
6315 elsif not Is_Overloadable (E) then
6317 -- Check for spurious conflict produced by a subprogram that has the
6318 -- same name as that of the enclosing generic package. The conflict
6319 -- occurs within an instance, between the subprogram and the renaming
6320 -- declaration for the package. After the subprogram, the package
6321 -- renaming declaration becomes hidden.
6323 if Ekind (E) = E_Package
6324 and then Present (Renamed_Object (E))
6325 and then Renamed_Object (E) = Current_Scope
6326 and then Nkind (Parent (Renamed_Object (E))) =
6327 N_Package_Specification
6328 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
6331 Set_Is_Immediately_Visible (E, False);
6332 Enter_Overloaded_Entity (S);
6333 Set_Homonym (S, Homonym (E));
6334 Check_Dispatching_Operation (S, Empty);
6335 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
6337 -- If the subprogram is implicit it is hidden by the previous
6338 -- declaration. However if it is dispatching, it must appear in the
6339 -- dispatch table anyway, because it can be dispatched to even if it
6340 -- cannot be called directly.
6342 elsif Present (Alias (S))
6343 and then not Comes_From_Source (S)
6345 Set_Scope (S, Current_Scope);
6347 if Is_Dispatching_Operation (Alias (S)) then
6348 Check_Dispatching_Operation (S, Empty);
6354 Error_Msg_Sloc := Sloc (E);
6356 -- Generate message,with useful additionalwarning if in generic
6358 if Is_Generic_Unit (E) then
6359 Error_Msg_N ("previous generic unit cannot be overloaded", S);
6360 Error_Msg_N ("\& conflicts with declaration#", S);
6362 Error_Msg_N ("& conflicts with declaration#", S);
6368 -- E exists and is overloadable
6371 -- Ada 2005 (AI-251): Derivation of abstract interface primitives
6372 -- need no check against the homonym chain. They are directly added
6373 -- to the list of primitive operations of Derived_Type.
6375 if Ada_Version >= Ada_05
6376 and then Present (Derived_Type)
6377 and then Is_Dispatching_Operation (Alias (S))
6378 and then Present (Find_Dispatching_Type (Alias (S)))
6379 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
6380 and then not Is_Predefined_Dispatching_Operation (Alias (S))
6382 goto Add_New_Entity;
6385 Check_Synchronized_Overriding (S, E, Overridden_Subp);
6387 -- Loop through E and its homonyms to determine if any of them is
6388 -- the candidate for overriding by S.
6390 while Present (E) loop
6392 -- Definitely not interesting if not in the current scope
6394 if Scope (E) /= Current_Scope then
6397 -- Check if we have type conformance
6399 elsif Type_Conformant (E, S) then
6401 -- If the old and new entities have the same profile and one
6402 -- is not the body of the other, then this is an error, unless
6403 -- one of them is implicitly declared.
6405 -- There are some cases when both can be implicit, for example
6406 -- when both a literal and a function that overrides it are
6407 -- inherited in a derivation, or when an inhertited operation
6408 -- of a tagged full type overrides the inherited operation of
6409 -- a private extension. Ada 83 had a special rule for the the
6410 -- literal case. In Ada95, the later implicit operation hides
6411 -- the former, and the literal is always the former. In the
6412 -- odd case where both are derived operations declared at the
6413 -- same point, both operations should be declared, and in that
6414 -- case we bypass the following test and proceed to the next
6415 -- part (this can only occur for certain obscure cases
6416 -- involving homographs in instances and can't occur for
6417 -- dispatching operations ???). Note that the following
6418 -- condition is less than clear. For example, it's not at all
6419 -- clear why there's a test for E_Entry here. ???
6421 if Present (Alias (S))
6422 and then (No (Alias (E))
6423 or else Comes_From_Source (E)
6424 or else Is_Dispatching_Operation (E))
6426 (Ekind (E) = E_Entry
6427 or else Ekind (E) /= E_Enumeration_Literal)
6429 -- When an derived operation is overloaded it may be due to
6430 -- the fact that the full view of a private extension
6431 -- re-inherits. It has to be dealt with.
6433 if Is_Package_Or_Generic_Package (Current_Scope)
6434 and then In_Private_Part (Current_Scope)
6436 Check_Operation_From_Private_View (S, E);
6439 -- In any case the implicit operation remains hidden by
6440 -- the existing declaration, which is overriding.
6442 Set_Is_Overriding_Operation (E);
6444 if Comes_From_Source (E) then
6445 Check_Overriding_Indicator (E, S, Is_Primitive => False);
6447 -- Indicate that E overrides the operation from which
6450 if Present (Alias (S)) then
6451 Set_Overridden_Operation (E, Alias (S));
6453 Set_Overridden_Operation (E, S);
6459 -- Within an instance, the renaming declarations for
6460 -- actual subprograms may become ambiguous, but they do
6461 -- not hide each other.
6463 elsif Ekind (E) /= E_Entry
6464 and then not Comes_From_Source (E)
6465 and then not Is_Generic_Instance (E)
6466 and then (Present (Alias (E))
6467 or else Is_Intrinsic_Subprogram (E))
6468 and then (not In_Instance
6469 or else No (Parent (E))
6470 or else Nkind (Unit_Declaration_Node (E)) /=
6471 N_Subprogram_Renaming_Declaration)
6473 -- A subprogram child unit is not allowed to override
6474 -- an inherited subprogram (10.1.1(20)).
6476 if Is_Child_Unit (S) then
6478 ("child unit overrides inherited subprogram in parent",
6483 if Is_Non_Overriding_Operation (E, S) then
6484 Enter_Overloaded_Entity (S);
6485 if No (Derived_Type)
6486 or else Is_Tagged_Type (Derived_Type)
6488 Check_Dispatching_Operation (S, Empty);
6494 -- E is a derived operation or an internal operator which
6495 -- is being overridden. Remove E from further visibility.
6496 -- Furthermore, if E is a dispatching operation, it must be
6497 -- replaced in the list of primitive operations of its type
6498 -- (see Override_Dispatching_Operation).
6500 Overridden_Subp := E;
6506 Prev := First_Entity (Current_Scope);
6508 while Present (Prev)
6509 and then Next_Entity (Prev) /= E
6514 -- It is possible for E to be in the current scope and
6515 -- yet not in the entity chain. This can only occur in a
6516 -- generic context where E is an implicit concatenation
6517 -- in the formal part, because in a generic body the
6518 -- entity chain starts with the formals.
6521 (Present (Prev) or else Chars (E) = Name_Op_Concat);
6523 -- E must be removed both from the entity_list of the
6524 -- current scope, and from the visibility chain
6526 if Debug_Flag_E then
6527 Write_Str ("Override implicit operation ");
6528 Write_Int (Int (E));
6532 -- If E is a predefined concatenation, it stands for four
6533 -- different operations. As a result, a single explicit
6534 -- declaration does not hide it. In a possible ambiguous
6535 -- situation, Disambiguate chooses the user-defined op,
6536 -- so it is correct to retain the previous internal one.
6538 if Chars (E) /= Name_Op_Concat
6539 or else Ekind (E) /= E_Operator
6541 -- For nondispatching derived operations that are
6542 -- overridden by a subprogram declared in the private
6543 -- part of a package, we retain the derived
6544 -- subprogram but mark it as not immediately visible.
6545 -- If the derived operation was declared in the
6546 -- visible part then this ensures that it will still
6547 -- be visible outside the package with the proper
6548 -- signature (calls from outside must also be
6549 -- directed to this version rather than the
6550 -- overriding one, unlike the dispatching case).
6551 -- Calls from inside the package will still resolve
6552 -- to the overriding subprogram since the derived one
6553 -- is marked as not visible within the package.
6555 -- If the private operation is dispatching, we achieve
6556 -- the overriding by keeping the implicit operation
6557 -- but setting its alias to be the overriding one. In
6558 -- this fashion the proper body is executed in all
6559 -- cases, but the original signature is used outside
6562 -- If the overriding is not in the private part, we
6563 -- remove the implicit operation altogether.
6565 if Is_Private_Declaration (S) then
6567 if not Is_Dispatching_Operation (E) then
6568 Set_Is_Immediately_Visible (E, False);
6570 -- Work done in Override_Dispatching_Operation,
6571 -- so nothing else need to be done here.
6577 -- Find predecessor of E in Homonym chain
6579 if E = Current_Entity (E) then
6582 Prev_Vis := Current_Entity (E);
6583 while Homonym (Prev_Vis) /= E loop
6584 Prev_Vis := Homonym (Prev_Vis);
6588 if Prev_Vis /= Empty then
6590 -- Skip E in the visibility chain
6592 Set_Homonym (Prev_Vis, Homonym (E));
6595 Set_Name_Entity_Id (Chars (E), Homonym (E));
6598 Set_Next_Entity (Prev, Next_Entity (E));
6600 if No (Next_Entity (Prev)) then
6601 Set_Last_Entity (Current_Scope, Prev);
6607 Enter_Overloaded_Entity (S);
6608 Set_Is_Overriding_Operation (S);
6609 Check_Overriding_Indicator (S, E, Is_Primitive => True);
6611 -- Indicate that S overrides the operation from which
6614 if Comes_From_Source (S) then
6615 if Present (Alias (E)) then
6616 Set_Overridden_Operation (S, Alias (E));
6618 Set_Overridden_Operation (S, E);
6622 if Is_Dispatching_Operation (E) then
6624 -- An overriding dispatching subprogram inherits the
6625 -- convention of the overridden subprogram (by
6628 Set_Convention (S, Convention (E));
6629 Check_Dispatching_Operation (S, E);
6632 Check_Dispatching_Operation (S, Empty);
6635 Check_For_Primitive_Subprogram
6636 (Is_Primitive_Subp, Is_Overriding => True);
6637 goto Check_Inequality;
6640 -- Apparent redeclarations in instances can occur when two
6641 -- formal types get the same actual type. The subprograms in
6642 -- in the instance are legal, even if not callable from the
6643 -- outside. Calls from within are disambiguated elsewhere.
6644 -- For dispatching operations in the visible part, the usual
6645 -- rules apply, and operations with the same profile are not
6648 elsif (In_Instance_Visible_Part
6649 and then not Is_Dispatching_Operation (E))
6650 or else In_Instance_Not_Visible
6654 -- Here we have a real error (identical profile)
6657 Error_Msg_Sloc := Sloc (E);
6659 -- Avoid cascaded errors if the entity appears in
6660 -- subsequent calls.
6662 Set_Scope (S, Current_Scope);
6664 -- Generate error, with extra useful warning for the case
6665 -- of a generic instance with no completion.
6667 if Is_Generic_Instance (S)
6668 and then not Has_Completion (E)
6671 ("instantiation cannot provide body for&", S);
6672 Error_Msg_N ("\& conflicts with declaration#", S);
6674 Error_Msg_N ("& conflicts with declaration#", S);
6681 -- If one subprogram has an access parameter and the other
6682 -- a parameter of an access type, calls to either might be
6683 -- ambiguous. Verify that parameters match except for the
6684 -- access parameter.
6686 if May_Hide_Profile then
6691 F1 := First_Formal (S);
6692 F2 := First_Formal (E);
6693 while Present (F1) and then Present (F2) loop
6694 if Is_Access_Type (Etype (F1)) then
6695 if not Is_Access_Type (Etype (F2))
6696 or else not Conforming_Types
6697 (Designated_Type (Etype (F1)),
6698 Designated_Type (Etype (F2)),
6701 May_Hide_Profile := False;
6705 not Conforming_Types
6706 (Etype (F1), Etype (F2), Type_Conformant)
6708 May_Hide_Profile := False;
6719 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
6730 -- On exit, we know that S is a new entity
6732 Enter_Overloaded_Entity (S);
6733 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6734 Check_Overriding_Indicator
6735 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6737 -- If S is a derived operation for an untagged type then by
6738 -- definition it's not a dispatching operation (even if the parent
6739 -- operation was dispatching), so we don't call
6740 -- Check_Dispatching_Operation in that case.
6742 if No (Derived_Type)
6743 or else Is_Tagged_Type (Derived_Type)
6745 Check_Dispatching_Operation (S, Empty);
6749 -- If this is a user-defined equality operator that is not a derived
6750 -- subprogram, create the corresponding inequality. If the operation is
6751 -- dispatching, the expansion is done elsewhere, and we do not create
6752 -- an explicit inequality operation.
6754 <<Check_Inequality>>
6755 if Chars (S) = Name_Op_Eq
6756 and then Etype (S) = Standard_Boolean
6757 and then Present (Parent (S))
6758 and then not Is_Dispatching_Operation (S)
6760 Make_Inequality_Operator (S);
6762 end New_Overloaded_Entity;
6764 ---------------------
6765 -- Process_Formals --
6766 ---------------------
6768 procedure Process_Formals
6770 Related_Nod : Node_Id)
6772 Param_Spec : Node_Id;
6774 Formal_Type : Entity_Id;
6778 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
6779 -- Check whether the default has a class-wide type. After analysis the
6780 -- default has the type of the formal, so we must also check explicitly
6781 -- for an access attribute.
6783 ---------------------------
6784 -- Is_Class_Wide_Default --
6785 ---------------------------
6787 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
6789 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
6790 or else (Nkind (D) = N_Attribute_Reference
6791 and then Attribute_Name (D) = Name_Access
6792 and then Is_Class_Wide_Type (Etype (Prefix (D))));
6793 end Is_Class_Wide_Default;
6795 -- Start of processing for Process_Formals
6798 -- In order to prevent premature use of the formals in the same formal
6799 -- part, the Ekind is left undefined until all default expressions are
6800 -- analyzed. The Ekind is established in a separate loop at the end.
6802 Param_Spec := First (T);
6803 while Present (Param_Spec) loop
6804 Formal := Defining_Identifier (Param_Spec);
6805 Set_Never_Set_In_Source (Formal, True);
6806 Enter_Name (Formal);
6808 -- Case of ordinary parameters
6810 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
6811 Find_Type (Parameter_Type (Param_Spec));
6812 Ptype := Parameter_Type (Param_Spec);
6814 if Ptype = Error then
6818 Formal_Type := Entity (Ptype);
6820 if Is_Incomplete_Type (Formal_Type)
6822 (Is_Class_Wide_Type (Formal_Type)
6823 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
6825 -- Ada 2005 (AI-326): Tagged incomplete types allowed
6827 if Is_Tagged_Type (Formal_Type) then
6830 -- Special handling of Value_Type for CIL case
6832 elsif Is_Value_Type (Formal_Type) then
6835 elsif Nkind (Parent (T)) /= N_Access_Function_Definition
6836 and then Nkind (Parent (T)) /= N_Access_Procedure_Definition
6838 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
6840 -- An incomplete type that is not tagged is allowed in an
6841 -- access-to-subprogram type only if it is a local declaration
6842 -- with a forthcoming completion (3.10.1 (9.2/2)).
6844 elsif Scope (Formal_Type) /= Scope (Current_Scope) then
6846 ("invalid use of limited view of type", Param_Spec);
6849 elsif Ekind (Formal_Type) = E_Void then
6850 Error_Msg_NE ("premature use of&",
6851 Parameter_Type (Param_Spec), Formal_Type);
6854 -- Ada 2005 (AI-231): Create and decorate an internal subtype
6855 -- declaration corresponding to the null-excluding type of the
6856 -- formal in the enclosing scope. Finally, replace the parameter
6857 -- type of the formal with the internal subtype.
6859 if Ada_Version >= Ada_05
6860 and then Null_Exclusion_Present (Param_Spec)
6862 if not Is_Access_Type (Formal_Type) then
6864 ("`NOT NULL` allowed only for an access type", Param_Spec);
6867 if Can_Never_Be_Null (Formal_Type)
6868 and then Comes_From_Source (Related_Nod)
6871 ("`NOT NULL` not allowed (& already excludes null)",
6877 Create_Null_Excluding_Itype
6879 Related_Nod => Related_Nod,
6880 Scope_Id => Scope (Current_Scope));
6882 -- If the designated type of the itype is an itype we
6883 -- decorate it with the Has_Delayed_Freeze attribute to
6884 -- avoid problems with the backend.
6887 -- type T is access procedure;
6888 -- procedure Op (O : not null T);
6890 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
6891 Set_Has_Delayed_Freeze (Formal_Type);
6896 -- An access formal type
6900 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
6902 -- No need to continue if we already notified errors
6904 if not Present (Formal_Type) then
6908 -- Ada 2005 (AI-254)
6911 AD : constant Node_Id :=
6912 Access_To_Subprogram_Definition
6913 (Parameter_Type (Param_Spec));
6915 if Present (AD) and then Protected_Present (AD) then
6917 Replace_Anonymous_Access_To_Protected_Subprogram
6923 Set_Etype (Formal, Formal_Type);
6924 Default := Expression (Param_Spec);
6926 if Present (Default) then
6927 if Out_Present (Param_Spec) then
6929 ("default initialization only allowed for IN parameters",
6933 -- Do the special preanalysis of the expression (see section on
6934 -- "Handling of Default Expressions" in the spec of package Sem).
6936 Analyze_Per_Use_Expression (Default, Formal_Type);
6938 -- Check that the designated type of an access parameter's default
6939 -- is not a class-wide type unless the parameter's designated type
6940 -- is also class-wide.
6942 if Ekind (Formal_Type) = E_Anonymous_Access_Type
6943 and then not From_With_Type (Formal_Type)
6944 and then Is_Class_Wide_Default (Default)
6945 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
6948 ("access to class-wide expression not allowed here", Default);
6952 -- Ada 2005 (AI-231): Static checks
6954 if Ada_Version >= Ada_05
6955 and then Is_Access_Type (Etype (Formal))
6956 and then Can_Never_Be_Null (Etype (Formal))
6958 Null_Exclusion_Static_Checks (Param_Spec);
6965 -- If this is the formal part of a function specification, analyze the
6966 -- subtype mark in the context where the formals are visible but not
6967 -- yet usable, and may hide outer homographs.
6969 if Nkind (Related_Nod) = N_Function_Specification then
6970 Analyze_Return_Type (Related_Nod);
6973 -- Now set the kind (mode) of each formal
6975 Param_Spec := First (T);
6977 while Present (Param_Spec) loop
6978 Formal := Defining_Identifier (Param_Spec);
6979 Set_Formal_Mode (Formal);
6981 if Ekind (Formal) = E_In_Parameter then
6982 Set_Default_Value (Formal, Expression (Param_Spec));
6984 if Present (Expression (Param_Spec)) then
6985 Default := Expression (Param_Spec);
6987 if Is_Scalar_Type (Etype (Default)) then
6989 (Parameter_Type (Param_Spec)) /= N_Access_Definition
6991 Formal_Type := Entity (Parameter_Type (Param_Spec));
6994 Formal_Type := Access_Definition
6995 (Related_Nod, Parameter_Type (Param_Spec));
6998 Apply_Scalar_Range_Check (Default, Formal_Type);
7006 end Process_Formals;
7008 ----------------------------
7009 -- Reference_Body_Formals --
7010 ----------------------------
7012 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
7017 if Error_Posted (Spec) then
7021 -- Iterate over both lists. They may be of different lengths if the two
7022 -- specs are not conformant.
7024 Fs := First_Formal (Spec);
7025 Fb := First_Formal (Bod);
7026 while Present (Fs) and then Present (Fb) loop
7027 Generate_Reference (Fs, Fb, 'b');
7030 Style.Check_Identifier (Fb, Fs);
7033 Set_Spec_Entity (Fb, Fs);
7034 Set_Referenced (Fs, False);
7038 end Reference_Body_Formals;
7040 -------------------------
7041 -- Set_Actual_Subtypes --
7042 -------------------------
7044 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
7045 Loc : constant Source_Ptr := Sloc (N);
7049 First_Stmt : Node_Id := Empty;
7050 AS_Needed : Boolean;
7053 -- If this is an emtpy initialization procedure, no need to create
7054 -- actual subtypes (small optimization).
7056 if Ekind (Subp) = E_Procedure
7057 and then Is_Null_Init_Proc (Subp)
7062 Formal := First_Formal (Subp);
7063 while Present (Formal) loop
7064 T := Etype (Formal);
7066 -- We never need an actual subtype for a constrained formal
7068 if Is_Constrained (T) then
7071 -- If we have unknown discriminants, then we do not need an actual
7072 -- subtype, or more accurately we cannot figure it out! Note that
7073 -- all class-wide types have unknown discriminants.
7075 elsif Has_Unknown_Discriminants (T) then
7078 -- At this stage we have an unconstrained type that may need an
7079 -- actual subtype. For sure the actual subtype is needed if we have
7080 -- an unconstrained array type.
7082 elsif Is_Array_Type (T) then
7085 -- The only other case needing an actual subtype is an unconstrained
7086 -- record type which is an IN parameter (we cannot generate actual
7087 -- subtypes for the OUT or IN OUT case, since an assignment can
7088 -- change the discriminant values. However we exclude the case of
7089 -- initialization procedures, since discriminants are handled very
7090 -- specially in this context, see the section entitled "Handling of
7091 -- Discriminants" in Einfo.
7093 -- We also exclude the case of Discrim_SO_Functions (functions used
7094 -- in front end layout mode for size/offset values), since in such
7095 -- functions only discriminants are referenced, and not only are such
7096 -- subtypes not needed, but they cannot always be generated, because
7097 -- of order of elaboration issues.
7099 elsif Is_Record_Type (T)
7100 and then Ekind (Formal) = E_In_Parameter
7101 and then Chars (Formal) /= Name_uInit
7102 and then not Is_Unchecked_Union (T)
7103 and then not Is_Discrim_SO_Function (Subp)
7107 -- All other cases do not need an actual subtype
7113 -- Generate actual subtypes for unconstrained arrays and
7114 -- unconstrained discriminated records.
7117 if Nkind (N) = N_Accept_Statement then
7119 -- If expansion is active, The formal is replaced by a local
7120 -- variable that renames the corresponding entry of the
7121 -- parameter block, and it is this local variable that may
7122 -- require an actual subtype.
7124 if Expander_Active then
7125 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
7127 Decl := Build_Actual_Subtype (T, Formal);
7130 if Present (Handled_Statement_Sequence (N)) then
7132 First (Statements (Handled_Statement_Sequence (N)));
7133 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
7134 Mark_Rewrite_Insertion (Decl);
7136 -- If the accept statement has no body, there will be no
7137 -- reference to the actuals, so no need to compute actual
7144 Decl := Build_Actual_Subtype (T, Formal);
7145 Prepend (Decl, Declarations (N));
7146 Mark_Rewrite_Insertion (Decl);
7149 -- The declaration uses the bounds of an existing object, and
7150 -- therefore needs no constraint checks.
7152 Analyze (Decl, Suppress => All_Checks);
7154 -- We need to freeze manually the generated type when it is
7155 -- inserted anywhere else than in a declarative part.
7157 if Present (First_Stmt) then
7158 Insert_List_Before_And_Analyze (First_Stmt,
7159 Freeze_Entity (Defining_Identifier (Decl), Loc));
7162 if Nkind (N) = N_Accept_Statement
7163 and then Expander_Active
7165 Set_Actual_Subtype (Renamed_Object (Formal),
7166 Defining_Identifier (Decl));
7168 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
7172 Next_Formal (Formal);
7174 end Set_Actual_Subtypes;
7176 ---------------------
7177 -- Set_Formal_Mode --
7178 ---------------------
7180 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
7181 Spec : constant Node_Id := Parent (Formal_Id);
7184 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
7185 -- since we ensure that corresponding actuals are always valid at the
7186 -- point of the call.
7188 if Out_Present (Spec) then
7189 if Ekind (Scope (Formal_Id)) = E_Function
7190 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
7192 Error_Msg_N ("functions can only have IN parameters", Spec);
7193 Set_Ekind (Formal_Id, E_In_Parameter);
7195 elsif In_Present (Spec) then
7196 Set_Ekind (Formal_Id, E_In_Out_Parameter);
7199 Set_Ekind (Formal_Id, E_Out_Parameter);
7200 Set_Never_Set_In_Source (Formal_Id, True);
7201 Set_Is_True_Constant (Formal_Id, False);
7202 Set_Current_Value (Formal_Id, Empty);
7206 Set_Ekind (Formal_Id, E_In_Parameter);
7209 -- Set Is_Known_Non_Null for access parameters since the language
7210 -- guarantees that access parameters are always non-null. We also set
7211 -- Can_Never_Be_Null, since there is no way to change the value.
7213 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
7215 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
7216 -- null; In Ada 2005, only if then null_exclusion is explicit.
7218 if Ada_Version < Ada_05
7219 or else Can_Never_Be_Null (Etype (Formal_Id))
7221 Set_Is_Known_Non_Null (Formal_Id);
7222 Set_Can_Never_Be_Null (Formal_Id);
7225 -- Ada 2005 (AI-231): Null-exclusion access subtype
7227 elsif Is_Access_Type (Etype (Formal_Id))
7228 and then Can_Never_Be_Null (Etype (Formal_Id))
7230 Set_Is_Known_Non_Null (Formal_Id);
7233 Set_Mechanism (Formal_Id, Default_Mechanism);
7234 Set_Formal_Validity (Formal_Id);
7235 end Set_Formal_Mode;
7237 -------------------------
7238 -- Set_Formal_Validity --
7239 -------------------------
7241 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
7243 -- If no validity checking, then we cannot assume anything about the
7244 -- validity of parameters, since we do not know there is any checking
7245 -- of the validity on the call side.
7247 if not Validity_Checks_On then
7250 -- If validity checking for parameters is enabled, this means we are
7251 -- not supposed to make any assumptions about argument values.
7253 elsif Validity_Check_Parameters then
7256 -- If we are checking in parameters, we will assume that the caller is
7257 -- also checking parameters, so we can assume the parameter is valid.
7259 elsif Ekind (Formal_Id) = E_In_Parameter
7260 and then Validity_Check_In_Params
7262 Set_Is_Known_Valid (Formal_Id, True);
7264 -- Similar treatment for IN OUT parameters
7266 elsif Ekind (Formal_Id) = E_In_Out_Parameter
7267 and then Validity_Check_In_Out_Params
7269 Set_Is_Known_Valid (Formal_Id, True);
7271 end Set_Formal_Validity;
7273 ------------------------
7274 -- Subtype_Conformant --
7275 ------------------------
7277 function Subtype_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7280 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result);
7282 end Subtype_Conformant;
7284 ---------------------
7285 -- Type_Conformant --
7286 ---------------------
7288 function Type_Conformant
7289 (New_Id : Entity_Id;
7291 Skip_Controlling_Formals : Boolean := False) return Boolean
7295 May_Hide_Profile := False;
7298 (New_Id, Old_Id, Type_Conformant, False, Result,
7299 Skip_Controlling_Formals => Skip_Controlling_Formals);
7301 end Type_Conformant;
7303 -------------------------------
7304 -- Valid_Operator_Definition --
7305 -------------------------------
7307 procedure Valid_Operator_Definition (Designator : Entity_Id) is
7310 Id : constant Name_Id := Chars (Designator);
7314 F := First_Formal (Designator);
7315 while Present (F) loop
7318 if Present (Default_Value (F)) then
7320 ("default values not allowed for operator parameters",
7327 -- Verify that user-defined operators have proper number of arguments
7328 -- First case of operators which can only be unary
7331 or else Id = Name_Op_Abs
7335 -- Case of operators which can be unary or binary
7337 elsif Id = Name_Op_Add
7338 or Id = Name_Op_Subtract
7340 N_OK := (N in 1 .. 2);
7342 -- All other operators can only be binary
7350 ("incorrect number of arguments for operator", Designator);
7354 and then Base_Type (Etype (Designator)) = Standard_Boolean
7355 and then not Is_Intrinsic_Subprogram (Designator)
7358 ("explicit definition of inequality not allowed", Designator);
7360 end Valid_Operator_Definition;