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 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Ch7; use Exp_Ch7;
35 with Exp_Tss; use Exp_Tss;
36 with Exp_Util; use Exp_Util;
37 with Fname; use Fname;
38 with Freeze; use Freeze;
39 with Itypes; use Itypes;
40 with Lib.Xref; use Lib.Xref;
41 with Layout; use Layout;
42 with Namet; use Namet;
44 with Nlists; use Nlists;
45 with Nmake; use Nmake;
47 with Output; use Output;
48 with Rtsfind; use Rtsfind;
50 with Sem_Cat; use Sem_Cat;
51 with Sem_Ch3; use Sem_Ch3;
52 with Sem_Ch4; use Sem_Ch4;
53 with Sem_Ch5; use Sem_Ch5;
54 with Sem_Ch8; use Sem_Ch8;
55 with Sem_Ch10; use Sem_Ch10;
56 with Sem_Ch12; use Sem_Ch12;
57 with Sem_Disp; use Sem_Disp;
58 with Sem_Dist; use Sem_Dist;
59 with Sem_Elim; use Sem_Elim;
60 with Sem_Eval; use Sem_Eval;
61 with Sem_Mech; use Sem_Mech;
62 with Sem_Prag; use Sem_Prag;
63 with Sem_Res; use Sem_Res;
64 with Sem_Util; use Sem_Util;
65 with Sem_Type; use Sem_Type;
66 with Sem_Warn; use Sem_Warn;
67 with Sinput; use Sinput;
68 with Stand; use Stand;
69 with Sinfo; use Sinfo;
70 with Sinfo.CN; use Sinfo.CN;
71 with Snames; use Snames;
72 with Stringt; use Stringt;
74 with Stylesw; use Stylesw;
75 with Tbuild; use Tbuild;
76 with Uintp; use Uintp;
77 with Urealp; use Urealp;
78 with Validsw; use Validsw;
80 package body Sem_Ch6 is
82 May_Hide_Profile : Boolean := False;
83 -- This flag is used to indicate that two formals in two subprograms being
84 -- checked for conformance differ only in that one is an access parameter
85 -- while the other is of a general access type with the same designated
86 -- type. In this case, if the rest of the signatures match, a call to
87 -- either subprogram may be ambiguous, which is worth a warning. The flag
88 -- is set in Compatible_Types, and the warning emitted in
89 -- New_Overloaded_Entity.
91 -----------------------
92 -- Local Subprograms --
93 -----------------------
95 procedure Analyze_Return_Statement (N : Node_Id);
96 -- Common processing for simple_ and extended_return_statements
98 procedure Analyze_Function_Return (N : Node_Id);
99 -- Subsidiary to Analyze_Return_Statement.
100 -- Called when the return statement applies to a [generic] function.
102 procedure Analyze_Return_Type (N : Node_Id);
103 -- Subsidiary to Process_Formals: analyze subtype mark in function
104 -- specification, in a context where the formals are visible and hide
107 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
108 -- Analyze a generic subprogram body. N is the body to be analyzed, and
109 -- Gen_Id is the defining entity Id for the corresponding spec.
111 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
112 -- If a subprogram has pragma Inline and inlining is active, use generic
113 -- machinery to build an unexpanded body for the subprogram. This body is
114 -- subsequenty used for inline expansions at call sites. If subprogram can
115 -- be inlined (depending on size and nature of local declarations) this
116 -- function returns true. Otherwise subprogram body is treated normally.
117 -- If proper warnings are enabled and the subprogram contains a construct
118 -- that cannot be inlined, the offending construct is flagged accordingly.
120 procedure Check_Conformance
123 Ctype : Conformance_Type;
125 Conforms : out Boolean;
126 Err_Loc : Node_Id := Empty;
127 Get_Inst : Boolean := False;
128 Skip_Controlling_Formals : Boolean := False);
129 -- Given two entities, this procedure checks that the profiles associated
130 -- with these entities meet the conformance criterion given by the third
131 -- parameter. If they conform, Conforms is set True and control returns
132 -- to the caller. If they do not conform, Conforms is set to False, and
133 -- in addition, if Errmsg is True on the call, proper messages are output
134 -- to complain about the conformance failure. If Err_Loc is non_Empty
135 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
136 -- error messages are placed on the appropriate part of the construct
137 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
138 -- against a formal access-to-subprogram type so Get_Instance_Of must
141 procedure Check_Overriding_Indicator
143 Overridden_Subp : Entity_Id;
144 Is_Primitive : Boolean);
145 -- Verify the consistency of an overriding_indicator given for subprogram
146 -- declaration, body, renaming, or instantiation. Overridden_Subp is set
147 -- if the scope where we are introducing the subprogram contains a
148 -- type-conformant subprogram that becomes hidden by the new subprogram.
149 -- Is_Primitive indicates whether the subprogram is primitive.
151 procedure Check_Subprogram_Order (N : Node_Id);
152 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
153 -- the alpha ordering rule for N if this ordering requirement applicable.
155 procedure Check_Returns
159 Proc : Entity_Id := Empty);
160 -- Called to check for missing return statements in a function body, or for
161 -- returns present in a procedure body which has No_Return set. HSS is the
162 -- handled statement sequence for the subprogram body. This procedure
163 -- checks all flow paths to make sure they either have return (Mode = 'F',
164 -- used for functions) or do not have a return (Mode = 'P', used for
165 -- No_Return procedures). The flag Err is set if there are any control
166 -- paths not explicitly terminated by a return in the function case, and is
167 -- True otherwise. Proc is the entity for the procedure case and is used
168 -- in posting the warning message.
170 procedure Enter_Overloaded_Entity (S : Entity_Id);
171 -- This procedure makes S, a new overloaded entity, into the first visible
172 -- entity with that name.
174 procedure Install_Entity (E : Entity_Id);
175 -- Make single entity visible. Used for generic formals as well
177 procedure Install_Formals (Id : Entity_Id);
178 -- On entry to a subprogram body, make the formals visible. Note that
179 -- simply placing the subprogram on the scope stack is not sufficient:
180 -- the formals must become the current entities for their names.
182 function Is_Non_Overriding_Operation
184 New_E : Entity_Id) return Boolean;
185 -- Enforce the rule given in 12.3(18): a private operation in an instance
186 -- overrides an inherited operation only if the corresponding operation
187 -- was overriding in the generic. This can happen for primitive operations
188 -- of types derived (in the generic unit) from formal private or formal
191 procedure Make_Inequality_Operator (S : Entity_Id);
192 -- Create the declaration for an inequality operator that is implicitly
193 -- created by a user-defined equality operator that yields a boolean.
195 procedure May_Need_Actuals (Fun : Entity_Id);
196 -- Flag functions that can be called without parameters, i.e. those that
197 -- have no parameters, or those for which defaults exist for all parameters
199 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id);
200 -- If there is a separate spec for a subprogram or generic subprogram, the
201 -- formals of the body are treated as references to the corresponding
202 -- formals of the spec. This reference does not count as an actual use of
203 -- the formal, in order to diagnose formals that are unused in the body.
205 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
206 -- Formal_Id is an formal parameter entity. This procedure deals with
207 -- setting the proper validity status for this entity, which depends
208 -- on the kind of parameter and the validity checking mode.
210 ------------------------------
211 -- Analyze_Return_Statement --
212 ------------------------------
214 procedure Analyze_Return_Statement (N : Node_Id) is
216 pragma Assert (Nkind (N) = N_Simple_Return_Statement
218 Nkind (N) = N_Extended_Return_Statement);
220 Returns_Object : constant Boolean :=
221 Nkind (N) = N_Extended_Return_Statement
223 (Nkind (N) = N_Simple_Return_Statement
224 and then Present (Expression (N)));
225 -- True if we're returning something; that is, "return <expression>;"
226 -- or "return Result : T [:= ...]". False for "return;". Used for error
227 -- checking: If Returns_Object is True, N should apply to a function
228 -- body; otherwise N should apply to a procedure body, entry body,
229 -- accept statement, or extended return statement.
231 function Find_What_It_Applies_To return Entity_Id;
232 -- Find the entity representing the innermost enclosing body, accept
233 -- statement, or extended return statement. If the result is a callable
234 -- construct or extended return statement, then this will be the value
235 -- of the Return_Applies_To attribute. Otherwise, the program is
236 -- illegal. See RM-6.5(4/2).
238 -----------------------------
239 -- Find_What_It_Applies_To --
240 -----------------------------
242 function Find_What_It_Applies_To return Entity_Id is
243 Result : Entity_Id := Empty;
246 -- Loop outward through the Scope_Stack, skipping blocks and loops
248 for J in reverse 0 .. Scope_Stack.Last loop
249 Result := Scope_Stack.Table (J).Entity;
250 exit when Ekind (Result) /= E_Block and then
251 Ekind (Result) /= E_Loop;
254 pragma Assert (Present (Result));
256 end Find_What_It_Applies_To;
258 -- Local declarations
260 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
261 Kind : constant Entity_Kind := Ekind (Scope_Id);
262 Loc : constant Source_Ptr := Sloc (N);
263 Stm_Entity : constant Entity_Id :=
265 (E_Return_Statement, Current_Scope, Loc, 'R');
267 -- Start of processing for Analyze_Return_Statement
270 Set_Return_Statement_Entity (N, Stm_Entity);
272 Set_Etype (Stm_Entity, Standard_Void_Type);
273 Set_Return_Applies_To (Stm_Entity, Scope_Id);
275 -- Place Return entity on scope stack, to simplify enforcement of 6.5
276 -- (4/2): an inner return statement will apply to this extended return.
278 if Nkind (N) = N_Extended_Return_Statement then
279 Push_Scope (Stm_Entity);
282 -- Check that pragma No_Return is obeyed
284 if No_Return (Scope_Id) then
285 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
288 -- Warn on any unassigned OUT parameters if in procedure
290 if Ekind (Scope_Id) = E_Procedure then
291 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
294 -- Check that functions return objects, and other things do not
296 if Kind = E_Function or else Kind = E_Generic_Function then
297 if not Returns_Object then
298 Error_Msg_N ("missing expression in return from function", N);
301 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
302 if Returns_Object then
303 Error_Msg_N ("procedure cannot return value (use function)", N);
306 elsif Kind = E_Entry or else Kind = E_Entry_Family then
307 if Returns_Object then
308 if Is_Protected_Type (Scope (Scope_Id)) then
309 Error_Msg_N ("entry body cannot return value", N);
311 Error_Msg_N ("accept statement cannot return value", N);
315 elsif Kind = E_Return_Statement then
317 -- We are nested within another return statement, which must be an
318 -- extended_return_statement.
320 if Returns_Object then
322 ("extended_return_statement cannot return value; " &
323 "use `""RETURN;""`", N);
327 Error_Msg_N ("illegal context for return statement", N);
330 if Kind = E_Function or else Kind = E_Generic_Function then
331 Analyze_Function_Return (N);
334 if Nkind (N) = N_Extended_Return_Statement then
338 Check_Unreachable_Code (N);
339 end Analyze_Return_Statement;
341 ---------------------------------------------
342 -- Analyze_Abstract_Subprogram_Declaration --
343 ---------------------------------------------
345 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
346 Designator : constant Entity_Id :=
347 Analyze_Subprogram_Specification (Specification (N));
348 Scop : constant Entity_Id := Current_Scope;
351 Generate_Definition (Designator);
352 Set_Is_Abstract_Subprogram (Designator);
353 New_Overloaded_Entity (Designator);
354 Check_Delayed_Subprogram (Designator);
356 Set_Categorization_From_Scope (Designator, Scop);
358 if Ekind (Scope (Designator)) = E_Protected_Type then
360 ("abstract subprogram not allowed in protected type", N);
362 -- Issue a warning if the abstract subprogram is neither a dispatching
363 -- operation nor an operation that overrides an inherited subprogram or
364 -- predefined operator, since this most likely indicates a mistake.
366 elsif Warn_On_Redundant_Constructs
367 and then not Is_Dispatching_Operation (Designator)
368 and then not Is_Overriding_Operation (Designator)
369 and then (not Is_Operator_Symbol_Name (Chars (Designator))
370 or else Scop /= Scope (Etype (First_Formal (Designator))))
373 ("?abstract subprogram is not dispatching or overriding", N);
376 Generate_Reference_To_Formals (Designator);
377 end Analyze_Abstract_Subprogram_Declaration;
379 ----------------------------------------
380 -- Analyze_Extended_Return_Statement --
381 ----------------------------------------
383 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
385 Analyze_Return_Statement (N);
386 end Analyze_Extended_Return_Statement;
388 ----------------------------
389 -- Analyze_Function_Call --
390 ----------------------------
392 procedure Analyze_Function_Call (N : Node_Id) is
393 P : constant Node_Id := Name (N);
394 L : constant List_Id := Parameter_Associations (N);
400 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
401 -- as B (A, X). If the rewriting is successful, the call has been
402 -- analyzed and we just return.
404 if Nkind (P) = N_Selected_Component
405 and then Name (N) /= P
406 and then Is_Rewrite_Substitution (N)
407 and then Present (Etype (N))
412 -- If error analyzing name, then set Any_Type as result type and return
414 if Etype (P) = Any_Type then
415 Set_Etype (N, Any_Type);
419 -- Otherwise analyze the parameters
423 while Present (Actual) loop
425 Check_Parameterless_Call (Actual);
431 end Analyze_Function_Call;
433 -----------------------------
434 -- Analyze_Function_Return --
435 -----------------------------
437 procedure Analyze_Function_Return (N : Node_Id) is
438 Loc : constant Source_Ptr := Sloc (N);
439 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
440 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
442 R_Type : constant Entity_Id := Etype (Scope_Id);
443 -- Function result subtype
445 procedure Check_Limited_Return (Expr : Node_Id);
446 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
447 -- limited types. Used only for simple return statements.
448 -- Expr is the expression returned.
450 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
451 -- Check that the return_subtype_indication properly matches the result
452 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
454 --------------------------
455 -- Check_Limited_Return --
456 --------------------------
458 procedure Check_Limited_Return (Expr : Node_Id) is
460 -- Ada 2005 (AI-318-02): Return-by-reference types have been
461 -- removed and replaced by anonymous access results. This is an
462 -- incompatibility with Ada 95. Not clear whether this should be
463 -- enforced yet or perhaps controllable with special switch. ???
465 if Is_Limited_Type (R_Type)
466 and then Comes_From_Source (N)
467 and then not In_Instance_Body
468 and then not OK_For_Limited_Init_In_05 (Expr)
472 if Ada_Version >= Ada_05
473 and then not Debug_Flag_Dot_L
474 and then not GNAT_Mode
477 ("(Ada 2005) cannot copy object of a limited type " &
478 "(RM-2005 6.5(5.5/2))", Expr);
479 if Is_Inherently_Limited_Type (R_Type) then
481 ("\return by reference not permitted in Ada 2005", Expr);
484 -- Warn in Ada 95 mode, to give folks a heads up about this
487 -- In GNAT mode, this is just a warning, to allow it to be
488 -- evilly turned off. Otherwise it is a real error.
490 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
491 if Is_Inherently_Limited_Type (R_Type) then
493 ("return by reference not permitted in Ada 2005 " &
494 "(RM-2005 6.5(5.5/2))?", Expr);
497 ("cannot copy object of a limited type in Ada 2005 " &
498 "(RM-2005 6.5(5.5/2))?", Expr);
501 -- Ada 95 mode, compatibility warnings disabled
504 return; -- skip continuation messages below
508 ("\consider switching to return of access type", Expr);
509 Explain_Limited_Type (R_Type, Expr);
511 end Check_Limited_Return;
513 -------------------------------------
514 -- Check_Return_Subtype_Indication --
515 -------------------------------------
517 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
518 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
519 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
520 -- Subtype given in the extended return statement;
521 -- this must match R_Type.
523 Subtype_Ind : constant Node_Id :=
524 Object_Definition (Original_Node (Obj_Decl));
526 R_Type_Is_Anon_Access :
528 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
530 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
532 Ekind (R_Type) = E_Anonymous_Access_Type;
533 -- True if return type of the function is an anonymous access type
534 -- Can't we make Is_Anonymous_Access_Type in einfo ???
536 R_Stm_Type_Is_Anon_Access :
538 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
540 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
542 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
543 -- True if type of the return object is an anonymous access type
546 -- First, avoid cascade errors:
548 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
552 -- "return access T" case; check that the return statement also has
553 -- "access T", and that the subtypes statically match:
555 if R_Type_Is_Anon_Access then
556 if R_Stm_Type_Is_Anon_Access then
557 if Base_Type (Designated_Type (R_Stm_Type)) /=
558 Base_Type (Designated_Type (R_Type))
559 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
562 ("subtype must statically match function result subtype",
563 Subtype_Mark (Subtype_Ind));
567 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
570 -- Subtype_indication case; check that the types are the same, and
571 -- statically match if appropriate:
573 elsif Base_Type (R_Stm_Type) = Base_Type (R_Type) then
574 if Is_Constrained (R_Type) then
575 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
577 ("subtype must statically match function result subtype",
582 -- If the function's result type doesn't match the return object
583 -- entity's type, then we check for the case where the result type
584 -- is class-wide, and allow the declaration if the type of the object
585 -- definition matches the class-wide type. This prevents rejection
586 -- in the case where the object declaration is initialized by a call
587 -- to a build-in-place function with a specific result type and the
588 -- object entity had its type changed to that specific type. (Note
589 -- that the ARG believes that return objects should be allowed to
590 -- have a type covered by a class-wide result type in any case, so
591 -- once that relaxation is made (see AI05-32), the above check for
592 -- type compatibility should be changed to test Covers rather than
593 -- equality, and then the following special test will no longer be
596 elsif Is_Class_Wide_Type (R_Type)
598 R_Type = Etype (Object_Definition (Original_Node (Obj_Decl)))
604 ("wrong type for return_subtype_indication", Subtype_Ind);
606 end Check_Return_Subtype_Indication;
608 ---------------------
609 -- Local Variables --
610 ---------------------
614 -- Start of processing for Analyze_Function_Return
617 Set_Return_Present (Scope_Id);
619 if Nkind (N) = N_Simple_Return_Statement then
620 Expr := Expression (N);
621 Analyze_And_Resolve (Expr, R_Type);
622 Check_Limited_Return (Expr);
625 -- Analyze parts specific to extended_return_statement:
628 Obj_Decl : constant Node_Id :=
629 Last (Return_Object_Declarations (N));
631 HSS : constant Node_Id := Handled_Statement_Sequence (N);
634 Expr := Expression (Obj_Decl);
636 -- Note: The check for OK_For_Limited_Init will happen in
637 -- Analyze_Object_Declaration; we treat it as a normal
638 -- object declaration.
642 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
643 Check_Return_Subtype_Indication (Obj_Decl);
645 if Present (HSS) then
648 if Present (Exception_Handlers (HSS)) then
650 -- ???Has_Nested_Block_With_Handler needs to be set.
651 -- Probably by creating an actual N_Block_Statement.
652 -- Probably in Expand.
658 Check_References (Stm_Entity);
662 -- Case of Expr present (Etype check defends against previous errors)
665 and then Present (Etype (Expr))
667 -- Apply constraint check. Note that this is done before the implicit
668 -- conversion of the expression done for anonymous access types to
669 -- ensure correct generation of the null-excluding check asssociated
670 -- with null-excluding expressions found in return statements.
672 Apply_Constraint_Check (Expr, R_Type);
674 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
675 -- type, apply an implicit conversion of the expression to that type
676 -- to force appropriate static and run-time accessibility checks.
678 if Ada_Version >= Ada_05
679 and then Ekind (R_Type) = E_Anonymous_Access_Type
681 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
682 Analyze_And_Resolve (Expr, R_Type);
685 if (Is_Class_Wide_Type (Etype (Expr))
686 or else Is_Dynamically_Tagged (Expr))
687 and then not Is_Class_Wide_Type (R_Type)
690 ("dynamically tagged expression not allowed!", Expr);
693 -- ??? A real run-time accessibility check is needed in cases
694 -- involving dereferences of access parameters. For now we just
695 -- check the static cases.
697 if (Ada_Version < Ada_05 or else Debug_Flag_Dot_L)
698 and then Is_Inherently_Limited_Type (Etype (Scope_Id))
699 and then Object_Access_Level (Expr) >
700 Subprogram_Access_Level (Scope_Id)
703 Make_Raise_Program_Error (Loc,
704 Reason => PE_Accessibility_Check_Failed));
708 ("cannot return a local value by reference?", N);
710 ("\& will be raised at run time?",
711 N, Standard_Program_Error);
715 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
716 and then Null_Exclusion_Present (Parent (Scope_Id))
718 Apply_Compile_Time_Constraint_Error
720 Msg => "(Ada 2005) null not allowed for "
721 & "null-excluding return?",
722 Reason => CE_Null_Not_Allowed);
725 end Analyze_Function_Return;
727 -------------------------------------
728 -- Analyze_Generic_Subprogram_Body --
729 -------------------------------------
731 procedure Analyze_Generic_Subprogram_Body
735 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
736 Kind : constant Entity_Kind := Ekind (Gen_Id);
742 -- Copy body and disable expansion while analyzing the generic For a
743 -- stub, do not copy the stub (which would load the proper body), this
744 -- will be done when the proper body is analyzed.
746 if Nkind (N) /= N_Subprogram_Body_Stub then
747 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
752 Spec := Specification (N);
754 -- Within the body of the generic, the subprogram is callable, and
755 -- behaves like the corresponding non-generic unit.
757 Body_Id := Defining_Entity (Spec);
759 if Kind = E_Generic_Procedure
760 and then Nkind (Spec) /= N_Procedure_Specification
762 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
765 elsif Kind = E_Generic_Function
766 and then Nkind (Spec) /= N_Function_Specification
768 Error_Msg_N ("invalid body for generic function ", Body_Id);
772 Set_Corresponding_Body (Gen_Decl, Body_Id);
774 if Has_Completion (Gen_Id)
775 and then Nkind (Parent (N)) /= N_Subunit
777 Error_Msg_N ("duplicate generic body", N);
780 Set_Has_Completion (Gen_Id);
783 if Nkind (N) = N_Subprogram_Body_Stub then
784 Set_Ekind (Defining_Entity (Specification (N)), Kind);
786 Set_Corresponding_Spec (N, Gen_Id);
789 if Nkind (Parent (N)) = N_Compilation_Unit then
790 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
793 -- Make generic parameters immediately visible in the body. They are
794 -- needed to process the formals declarations. Then make the formals
795 -- visible in a separate step.
801 First_Ent : Entity_Id;
804 First_Ent := First_Entity (Gen_Id);
807 while Present (E) and then not Is_Formal (E) loop
812 Set_Use (Generic_Formal_Declarations (Gen_Decl));
814 -- Now generic formals are visible, and the specification can be
815 -- analyzed, for subsequent conformance check.
817 Body_Id := Analyze_Subprogram_Specification (Spec);
819 -- Make formal parameters visible
823 -- E is the first formal parameter, we loop through the formals
824 -- installing them so that they will be visible.
826 Set_First_Entity (Gen_Id, E);
827 while Present (E) loop
833 -- Visible generic entity is callable within its own body
835 Set_Ekind (Gen_Id, Ekind (Body_Id));
836 Set_Ekind (Body_Id, E_Subprogram_Body);
837 Set_Convention (Body_Id, Convention (Gen_Id));
838 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
839 Set_Scope (Body_Id, Scope (Gen_Id));
840 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
842 if Nkind (N) = N_Subprogram_Body_Stub then
844 -- No body to analyze, so restore state of generic unit
846 Set_Ekind (Gen_Id, Kind);
847 Set_Ekind (Body_Id, Kind);
849 if Present (First_Ent) then
850 Set_First_Entity (Gen_Id, First_Ent);
857 -- If this is a compilation unit, it must be made visible explicitly,
858 -- because the compilation of the declaration, unlike other library
859 -- unit declarations, does not. If it is not a unit, the following
860 -- is redundant but harmless.
862 Set_Is_Immediately_Visible (Gen_Id);
863 Reference_Body_Formals (Gen_Id, Body_Id);
865 if Is_Child_Unit (Gen_Id) then
866 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
869 Set_Actual_Subtypes (N, Current_Scope);
870 Analyze_Declarations (Declarations (N));
872 Analyze (Handled_Statement_Sequence (N));
874 Save_Global_References (Original_Node (N));
876 -- Prior to exiting the scope, include generic formals again (if any
877 -- are present) in the set of local entities.
879 if Present (First_Ent) then
880 Set_First_Entity (Gen_Id, First_Ent);
883 Check_References (Gen_Id);
886 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
888 Check_Subprogram_Order (N);
890 -- Outside of its body, unit is generic again
892 Set_Ekind (Gen_Id, Kind);
893 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
896 Style.Check_Identifier (Body_Id, Gen_Id);
899 end Analyze_Generic_Subprogram_Body;
901 -----------------------------
902 -- Analyze_Operator_Symbol --
903 -----------------------------
905 -- An operator symbol such as "+" or "and" may appear in context where the
906 -- literal denotes an entity name, such as "+"(x, y) or in context when it
907 -- is just a string, as in (conjunction = "or"). In these cases the parser
908 -- generates this node, and the semantics does the disambiguation. Other
909 -- such case are actuals in an instantiation, the generic unit in an
910 -- instantiation, and pragma arguments.
912 procedure Analyze_Operator_Symbol (N : Node_Id) is
913 Par : constant Node_Id := Parent (N);
916 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
917 or else Nkind (Par) = N_Function_Instantiation
918 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
919 or else (Nkind (Par) = N_Pragma_Argument_Association
920 and then not Is_Pragma_String_Literal (Par))
921 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
922 or else (Nkind (Par) = N_Attribute_Reference
923 and then Attribute_Name (Par) /= Name_Value)
925 Find_Direct_Name (N);
928 Change_Operator_Symbol_To_String_Literal (N);
931 end Analyze_Operator_Symbol;
933 -----------------------------------
934 -- Analyze_Parameter_Association --
935 -----------------------------------
937 procedure Analyze_Parameter_Association (N : Node_Id) is
939 Analyze (Explicit_Actual_Parameter (N));
940 end Analyze_Parameter_Association;
942 ----------------------------
943 -- Analyze_Procedure_Call --
944 ----------------------------
946 procedure Analyze_Procedure_Call (N : Node_Id) is
947 Loc : constant Source_Ptr := Sloc (N);
948 P : constant Node_Id := Name (N);
949 Actuals : constant List_Id := Parameter_Associations (N);
953 procedure Analyze_Call_And_Resolve;
954 -- Do Analyze and Resolve calls for procedure call
956 ------------------------------
957 -- Analyze_Call_And_Resolve --
958 ------------------------------
960 procedure Analyze_Call_And_Resolve is
962 if Nkind (N) = N_Procedure_Call_Statement then
964 Resolve (N, Standard_Void_Type);
968 end Analyze_Call_And_Resolve;
970 -- Start of processing for Analyze_Procedure_Call
973 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
974 -- a procedure call or an entry call. The prefix may denote an access
975 -- to subprogram type, in which case an implicit dereference applies.
976 -- If the prefix is an indexed component (without implicit defererence)
977 -- then the construct denotes a call to a member of an entire family.
978 -- If the prefix is a simple name, it may still denote a call to a
979 -- parameterless member of an entry family. Resolution of these various
980 -- interpretations is delicate.
984 -- If this is a call of the form Obj.Op, the call may have been
985 -- analyzed and possibly rewritten into a block, in which case
992 -- If error analyzing prefix, then set Any_Type as result and return
994 if Etype (P) = Any_Type then
995 Set_Etype (N, Any_Type);
999 -- Otherwise analyze the parameters
1001 if Present (Actuals) then
1002 Actual := First (Actuals);
1004 while Present (Actual) loop
1006 Check_Parameterless_Call (Actual);
1011 -- Special processing for Elab_Spec and Elab_Body calls
1013 if Nkind (P) = N_Attribute_Reference
1014 and then (Attribute_Name (P) = Name_Elab_Spec
1015 or else Attribute_Name (P) = Name_Elab_Body)
1017 if Present (Actuals) then
1019 ("no parameters allowed for this call", First (Actuals));
1023 Set_Etype (N, Standard_Void_Type);
1026 elsif Is_Entity_Name (P)
1027 and then Is_Record_Type (Etype (Entity (P)))
1028 and then Remote_AST_I_Dereference (P)
1032 elsif Is_Entity_Name (P)
1033 and then Ekind (Entity (P)) /= E_Entry_Family
1035 if Is_Access_Type (Etype (P))
1036 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1037 and then No (Actuals)
1038 and then Comes_From_Source (N)
1040 Error_Msg_N ("missing explicit dereference in call", N);
1043 Analyze_Call_And_Resolve;
1045 -- If the prefix is the simple name of an entry family, this is
1046 -- a parameterless call from within the task body itself.
1048 elsif Is_Entity_Name (P)
1049 and then Nkind (P) = N_Identifier
1050 and then Ekind (Entity (P)) = E_Entry_Family
1051 and then Present (Actuals)
1052 and then No (Next (First (Actuals)))
1054 -- Can be call to parameterless entry family. What appears to be the
1055 -- sole argument is in fact the entry index. Rewrite prefix of node
1056 -- accordingly. Source representation is unchanged by this
1060 Make_Indexed_Component (Loc,
1062 Make_Selected_Component (Loc,
1063 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1064 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1065 Expressions => Actuals);
1066 Set_Name (N, New_N);
1067 Set_Etype (New_N, Standard_Void_Type);
1068 Set_Parameter_Associations (N, No_List);
1069 Analyze_Call_And_Resolve;
1071 elsif Nkind (P) = N_Explicit_Dereference then
1072 if Ekind (Etype (P)) = E_Subprogram_Type then
1073 Analyze_Call_And_Resolve;
1075 Error_Msg_N ("expect access to procedure in call", P);
1078 -- The name can be a selected component or an indexed component that
1079 -- yields an access to subprogram. Such a prefix is legal if the call
1080 -- has parameter associations.
1082 elsif Is_Access_Type (Etype (P))
1083 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1085 if Present (Actuals) then
1086 Analyze_Call_And_Resolve;
1088 Error_Msg_N ("missing explicit dereference in call ", N);
1091 -- If not an access to subprogram, then the prefix must resolve to the
1092 -- name of an entry, entry family, or protected operation.
1094 -- For the case of a simple entry call, P is a selected component where
1095 -- the prefix is the task and the selector name is the entry. A call to
1096 -- a protected procedure will have the same syntax. If the protected
1097 -- object contains overloaded operations, the entity may appear as a
1098 -- function, the context will select the operation whose type is Void.
1100 elsif Nkind (P) = N_Selected_Component
1101 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1103 Ekind (Entity (Selector_Name (P))) = E_Procedure
1105 Ekind (Entity (Selector_Name (P))) = E_Function)
1107 Analyze_Call_And_Resolve;
1109 elsif Nkind (P) = N_Selected_Component
1110 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1111 and then Present (Actuals)
1112 and then No (Next (First (Actuals)))
1114 -- Can be call to parameterless entry family. What appears to be the
1115 -- sole argument is in fact the entry index. Rewrite prefix of node
1116 -- accordingly. Source representation is unchanged by this
1120 Make_Indexed_Component (Loc,
1121 Prefix => New_Copy (P),
1122 Expressions => Actuals);
1123 Set_Name (N, New_N);
1124 Set_Etype (New_N, Standard_Void_Type);
1125 Set_Parameter_Associations (N, No_List);
1126 Analyze_Call_And_Resolve;
1128 -- For the case of a reference to an element of an entry family, P is
1129 -- an indexed component whose prefix is a selected component (task and
1130 -- entry family), and whose index is the entry family index.
1132 elsif Nkind (P) = N_Indexed_Component
1133 and then Nkind (Prefix (P)) = N_Selected_Component
1134 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1136 Analyze_Call_And_Resolve;
1138 -- If the prefix is the name of an entry family, it is a call from
1139 -- within the task body itself.
1141 elsif Nkind (P) = N_Indexed_Component
1142 and then Nkind (Prefix (P)) = N_Identifier
1143 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1146 Make_Selected_Component (Loc,
1147 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1148 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1149 Rewrite (Prefix (P), New_N);
1151 Analyze_Call_And_Resolve;
1153 -- Anything else is an error
1156 Error_Msg_N ("invalid procedure or entry call", N);
1158 end Analyze_Procedure_Call;
1160 -------------------------------------
1161 -- Analyze_Simple_Return_Statement --
1162 -------------------------------------
1164 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1166 if Present (Expression (N)) then
1167 Mark_Coextensions (N, Expression (N));
1170 Analyze_Return_Statement (N);
1171 end Analyze_Simple_Return_Statement;
1173 -------------------------
1174 -- Analyze_Return_Type --
1175 -------------------------
1177 procedure Analyze_Return_Type (N : Node_Id) is
1178 Designator : constant Entity_Id := Defining_Entity (N);
1179 Typ : Entity_Id := Empty;
1182 -- Normal case where result definition does not indicate an error
1184 if Result_Definition (N) /= Error then
1185 if Nkind (Result_Definition (N)) = N_Access_Definition then
1186 Typ := Access_Definition (N, Result_Definition (N));
1187 Set_Parent (Typ, Result_Definition (N));
1188 Set_Is_Local_Anonymous_Access (Typ);
1189 Set_Etype (Designator, Typ);
1191 -- Subtype_Mark case
1194 Find_Type (Result_Definition (N));
1195 Typ := Entity (Result_Definition (N));
1196 Set_Etype (Designator, Typ);
1198 if Ekind (Typ) = E_Incomplete_Type
1199 and then Is_Value_Type (Typ)
1203 elsif Ekind (Typ) = E_Incomplete_Type
1204 or else (Is_Class_Wide_Type (Typ)
1206 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1209 ("invalid use of incomplete type", Result_Definition (N));
1213 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1215 Null_Exclusion_Static_Checks (N);
1217 -- Case where result definition does indicate an error
1220 Set_Etype (Designator, Any_Type);
1222 end Analyze_Return_Type;
1224 -----------------------------
1225 -- Analyze_Subprogram_Body --
1226 -----------------------------
1228 -- This procedure is called for regular subprogram bodies, generic bodies,
1229 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1230 -- specification matters, and is used to create a proper declaration for
1231 -- the subprogram, or to perform conformance checks.
1233 procedure Analyze_Subprogram_Body (N : Node_Id) is
1234 Loc : constant Source_Ptr := Sloc (N);
1235 Body_Spec : constant Node_Id := Specification (N);
1236 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1237 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1238 Body_Deleted : constant Boolean := False;
1241 Spec_Id : Entity_Id;
1242 Spec_Decl : Node_Id := Empty;
1243 Last_Formal : Entity_Id := Empty;
1244 Conformant : Boolean;
1245 Missing_Ret : Boolean;
1248 procedure Check_Anonymous_Return;
1249 -- (Ada 2005): if a function returns an access type that denotes a task,
1250 -- or a type that contains tasks, we must create a master entity for
1251 -- the anonymous type, which typically will be used in an allocator
1252 -- in the body of the function.
1254 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1255 -- Look ahead to recognize a pragma that may appear after the body.
1256 -- If there is a previous spec, check that it appears in the same
1257 -- declarative part. If the pragma is Inline_Always, perform inlining
1258 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1259 -- If the body acts as a spec, and inlining is required, we create a
1260 -- subprogram declaration for it, in order to attach the body to inline.
1262 procedure Copy_Parameter_List (Plist : List_Id);
1263 -- Utility to create a parameter profile for a new subprogram spec,
1264 -- when the subprogram has a body that acts as spec. This is done for
1265 -- some cases of inlining, and for private protected ops.
1267 procedure Verify_Overriding_Indicator;
1268 -- If there was a previous spec, the entity has been entered in the
1269 -- current scope previously. If the body itself carries an overriding
1270 -- indicator, check that it is consistent with the known status of the
1273 ----------------------------
1274 -- Check_Anonymous_Return --
1275 ----------------------------
1277 procedure Check_Anonymous_Return is
1282 if Present (Spec_Id) then
1288 if Ekind (Scop) = E_Function
1289 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1290 and then Has_Task (Designated_Type (Etype (Scop)))
1291 and then Expander_Active
1294 Make_Object_Declaration (Loc,
1295 Defining_Identifier =>
1296 Make_Defining_Identifier (Loc, Name_uMaster),
1297 Constant_Present => True,
1298 Object_Definition =>
1299 New_Reference_To (RTE (RE_Master_Id), Loc),
1301 Make_Explicit_Dereference (Loc,
1302 New_Reference_To (RTE (RE_Current_Master), Loc)));
1304 if Present (Declarations (N)) then
1305 Prepend (Decl, Declarations (N));
1307 Set_Declarations (N, New_List (Decl));
1310 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1311 Set_Has_Master_Entity (Scop);
1313 end Check_Anonymous_Return;
1315 -------------------------
1316 -- Check_Inline_Pragma --
1317 -------------------------
1319 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1324 if not Expander_Active then
1328 if Is_List_Member (N)
1329 and then Present (Next (N))
1330 and then Nkind (Next (N)) = N_Pragma
1334 if Nkind (Prag) = N_Pragma
1336 (Get_Pragma_Id (Chars (Prag)) = Pragma_Inline_Always
1339 and then Get_Pragma_Id (Chars (Prag)) = Pragma_Inline))
1342 (Expression (First (Pragma_Argument_Associations (Prag))))
1353 if Present (Prag) then
1354 if Present (Spec_Id) then
1355 if List_Containing (N) =
1356 List_Containing (Unit_Declaration_Node (Spec_Id))
1362 -- Create a subprogram declaration, to make treatment uniform
1365 Subp : constant Entity_Id :=
1366 Make_Defining_Identifier (Loc, Chars (Body_Id));
1367 Decl : constant Node_Id :=
1368 Make_Subprogram_Declaration (Loc,
1369 Specification => New_Copy_Tree (Specification (N)));
1371 Set_Defining_Unit_Name (Specification (Decl), Subp);
1373 if Present (First_Formal (Body_Id)) then
1375 Copy_Parameter_List (Plist);
1376 Set_Parameter_Specifications
1377 (Specification (Decl), Plist);
1380 Insert_Before (N, Decl);
1383 Set_Has_Pragma_Inline (Subp);
1385 if Get_Pragma_Id (Chars (Prag)) = Pragma_Inline_Always then
1386 Set_Is_Inlined (Subp);
1387 Set_Next_Rep_Item (Prag, First_Rep_Item (Subp));
1388 Set_First_Rep_Item (Subp, Prag);
1395 end Check_Inline_Pragma;
1397 -------------------------
1398 -- Copy_Parameter_List --
1399 -------------------------
1401 procedure Copy_Parameter_List (Plist : List_Id) is
1405 Formal := First_Formal (Body_Id);
1407 while Present (Formal) loop
1409 (Make_Parameter_Specification (Loc,
1410 Defining_Identifier =>
1411 Make_Defining_Identifier (Sloc (Formal),
1412 Chars => Chars (Formal)),
1413 In_Present => In_Present (Parent (Formal)),
1414 Out_Present => Out_Present (Parent (Formal)),
1416 New_Reference_To (Etype (Formal), Loc),
1418 New_Copy_Tree (Expression (Parent (Formal)))),
1421 Next_Formal (Formal);
1423 end Copy_Parameter_List;
1425 ---------------------------------
1426 -- Verify_Overriding_Indicator --
1427 ---------------------------------
1429 procedure Verify_Overriding_Indicator is
1431 if Must_Override (Body_Spec)
1432 and then not Is_Overriding_Operation (Spec_Id)
1435 ("subprogram& is not overriding", Body_Spec, Spec_Id);
1437 elsif Must_Not_Override (Body_Spec) then
1438 if Is_Overriding_Operation (Spec_Id) then
1440 ("subprogram& overrides inherited operation",
1441 Body_Spec, Spec_Id);
1443 -- If this is not a primitive operation the overriding indicator
1444 -- is altogether illegal.
1446 elsif not Is_Primitive (Spec_Id) then
1447 Error_Msg_N ("overriding indicator only allowed " &
1448 "if subprogram is primitive",
1452 end Verify_Overriding_Indicator;
1454 -- Start of processing for Analyze_Subprogram_Body
1457 if Debug_Flag_C then
1458 Write_Str ("==== Compiling subprogram body ");
1459 Write_Name (Chars (Body_Id));
1460 Write_Str (" from ");
1461 Write_Location (Loc);
1465 Trace_Scope (N, Body_Id, " Analyze subprogram");
1467 -- Generic subprograms are handled separately. They always have a
1468 -- generic specification. Determine whether current scope has a
1469 -- previous declaration.
1471 -- If the subprogram body is defined within an instance of the same
1472 -- name, the instance appears as a package renaming, and will be hidden
1473 -- within the subprogram.
1475 if Present (Prev_Id)
1476 and then not Is_Overloadable (Prev_Id)
1477 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
1478 or else Comes_From_Source (Prev_Id))
1480 if Is_Generic_Subprogram (Prev_Id) then
1482 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1483 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1485 Analyze_Generic_Subprogram_Body (N, Spec_Id);
1489 -- Previous entity conflicts with subprogram name. Attempting to
1490 -- enter name will post error.
1492 Enter_Name (Body_Id);
1496 -- Non-generic case, find the subprogram declaration, if one was seen,
1497 -- or enter new overloaded entity in the current scope. If the
1498 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
1499 -- part of the context of one of its subunits. No need to redo the
1502 elsif Prev_Id = Body_Id
1503 and then Has_Completion (Body_Id)
1508 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
1510 if Nkind (N) = N_Subprogram_Body_Stub
1511 or else No (Corresponding_Spec (N))
1513 Spec_Id := Find_Corresponding_Spec (N);
1515 -- If this is a duplicate body, no point in analyzing it
1517 if Error_Posted (N) then
1521 -- A subprogram body should cause freezing of its own declaration,
1522 -- but if there was no previous explicit declaration, then the
1523 -- subprogram will get frozen too late (there may be code within
1524 -- the body that depends on the subprogram having been frozen,
1525 -- such as uses of extra formals), so we force it to be frozen
1526 -- here. Same holds if the body and the spec are compilation
1529 if No (Spec_Id) then
1530 Freeze_Before (N, Body_Id);
1532 elsif Nkind (Parent (N)) = N_Compilation_Unit then
1533 Freeze_Before (N, Spec_Id);
1536 Spec_Id := Corresponding_Spec (N);
1540 -- Do not inline any subprogram that contains nested subprograms, since
1541 -- the backend inlining circuit seems to generate uninitialized
1542 -- references in this case. We know this happens in the case of front
1543 -- end ZCX support, but it also appears it can happen in other cases as
1544 -- well. The backend often rejects attempts to inline in the case of
1545 -- nested procedures anyway, so little if anything is lost by this.
1546 -- Note that this is test is for the benefit of the back-end. There is
1547 -- a separate test for front-end inlining that also rejects nested
1550 -- Do not do this test if errors have been detected, because in some
1551 -- error cases, this code blows up, and we don't need it anyway if
1552 -- there have been errors, since we won't get to the linker anyway.
1554 if Comes_From_Source (Body_Id)
1555 and then Serious_Errors_Detected = 0
1559 P_Ent := Scope (P_Ent);
1560 exit when No (P_Ent) or else P_Ent = Standard_Standard;
1562 if Is_Subprogram (P_Ent) then
1563 Set_Is_Inlined (P_Ent, False);
1565 if Comes_From_Source (P_Ent)
1566 and then Has_Pragma_Inline (P_Ent)
1569 ("cannot inline& (nested subprogram)?",
1576 Check_Inline_Pragma (Spec_Id);
1578 -- Case of fully private operation in the body of the protected type.
1579 -- We must create a declaration for the subprogram, in order to attach
1580 -- the protected subprogram that will be used in internal calls.
1583 and then Comes_From_Source (N)
1584 and then Is_Protected_Type (Current_Scope)
1593 Formal := First_Formal (Body_Id);
1595 -- The protected operation always has at least one formal, namely
1596 -- the object itself, but it is only placed in the parameter list
1597 -- if expansion is enabled.
1600 or else Expander_Active
1608 Copy_Parameter_List (Plist);
1610 if Nkind (Body_Spec) = N_Procedure_Specification then
1612 Make_Procedure_Specification (Loc,
1613 Defining_Unit_Name =>
1614 Make_Defining_Identifier (Sloc (Body_Id),
1615 Chars => Chars (Body_Id)),
1616 Parameter_Specifications => Plist);
1619 Make_Function_Specification (Loc,
1620 Defining_Unit_Name =>
1621 Make_Defining_Identifier (Sloc (Body_Id),
1622 Chars => Chars (Body_Id)),
1623 Parameter_Specifications => Plist,
1624 Result_Definition =>
1625 New_Occurrence_Of (Etype (Body_Id), Loc));
1629 Make_Subprogram_Declaration (Loc,
1630 Specification => New_Spec);
1631 Insert_Before (N, Decl);
1632 Spec_Id := Defining_Unit_Name (New_Spec);
1634 -- Indicate that the entity comes from source, to ensure that
1635 -- cross-reference information is properly generated. The body
1636 -- itself is rewritten during expansion, and the body entity will
1637 -- not appear in calls to the operation.
1639 Set_Comes_From_Source (Spec_Id, True);
1641 Set_Has_Completion (Spec_Id);
1642 Set_Convention (Spec_Id, Convention_Protected);
1645 elsif Present (Spec_Id) then
1646 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1647 Verify_Overriding_Indicator;
1649 -- In general, the spec will be frozen when we start analyzing the
1650 -- body. However, for internally generated operations, such as
1651 -- wrapper functions for inherited operations with controlling
1652 -- results, the spec may not have been frozen by the time we
1653 -- expand the freeze actions that include the bodies. In particular,
1654 -- extra formals for accessibility or for return-in-place may need
1655 -- to be generated. Freeze nodes, if any, are inserted before the
1658 if not Is_Frozen (Spec_Id)
1659 and then Expander_Active
1661 -- Force the generation of its freezing node to ensure proper
1662 -- management of access types in the backend.
1664 -- This is definitely needed for some cases, but it is not clear
1665 -- why, to be investigated further???
1667 Set_Has_Delayed_Freeze (Spec_Id);
1668 Insert_Actions (N, Freeze_Entity (Spec_Id, Loc));
1672 -- Place subprogram on scope stack, and make formals visible. If there
1673 -- is a spec, the visible entity remains that of the spec.
1675 if Present (Spec_Id) then
1676 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1678 if Is_Child_Unit (Spec_Id) then
1679 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
1683 Style.Check_Identifier (Body_Id, Spec_Id);
1686 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1687 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1689 if Is_Abstract_Subprogram (Spec_Id) then
1690 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1693 Set_Convention (Body_Id, Convention (Spec_Id));
1694 Set_Has_Completion (Spec_Id);
1696 if Is_Protected_Type (Scope (Spec_Id)) then
1697 Set_Privals_Chain (Spec_Id, New_Elmt_List);
1700 -- If this is a body generated for a renaming, do not check for
1701 -- full conformance. The check is redundant, because the spec of
1702 -- the body is a copy of the spec in the renaming declaration,
1703 -- and the test can lead to spurious errors on nested defaults.
1705 if Present (Spec_Decl)
1706 and then not Comes_From_Source (N)
1708 (Nkind (Original_Node (Spec_Decl)) =
1709 N_Subprogram_Renaming_Declaration
1710 or else (Present (Corresponding_Body (Spec_Decl))
1712 Nkind (Unit_Declaration_Node
1713 (Corresponding_Body (Spec_Decl))) =
1714 N_Subprogram_Renaming_Declaration))
1720 Fully_Conformant, True, Conformant, Body_Id);
1723 -- If the body is not fully conformant, we have to decide if we
1724 -- should analyze it or not. If it has a really messed up profile
1725 -- then we probably should not analyze it, since we will get too
1726 -- many bogus messages.
1728 -- Our decision is to go ahead in the non-fully conformant case
1729 -- only if it is at least mode conformant with the spec. Note
1730 -- that the call to Check_Fully_Conformant has issued the proper
1731 -- error messages to complain about the lack of conformance.
1734 and then not Mode_Conformant (Body_Id, Spec_Id)
1740 if Spec_Id /= Body_Id then
1741 Reference_Body_Formals (Spec_Id, Body_Id);
1744 if Nkind (N) /= N_Subprogram_Body_Stub then
1745 Set_Corresponding_Spec (N, Spec_Id);
1747 -- Ada 2005 (AI-345): If the operation is a primitive operation
1748 -- of a concurrent type, the type of the first parameter has been
1749 -- replaced with the corresponding record, which is the proper
1750 -- run-time structure to use. However, within the body there may
1751 -- be uses of the formals that depend on primitive operations
1752 -- of the type (in particular calls in prefixed form) for which
1753 -- we need the original concurrent type. The operation may have
1754 -- several controlling formals, so the replacement must be done
1757 if Comes_From_Source (Spec_Id)
1758 and then Present (First_Entity (Spec_Id))
1759 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
1760 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
1762 Present (Abstract_Interfaces (Etype (First_Entity (Spec_Id))))
1765 (Corresponding_Concurrent_Type
1766 (Etype (First_Entity (Spec_Id))))
1769 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
1773 Form := First_Formal (Spec_Id);
1774 while Present (Form) loop
1775 if Etype (Form) = Typ then
1776 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
1784 -- Now make the formals visible, and place subprogram
1787 Install_Formals (Spec_Id);
1788 Last_Formal := Last_Entity (Spec_Id);
1789 Push_Scope (Spec_Id);
1791 -- Make sure that the subprogram is immediately visible. For
1792 -- child units that have no separate spec this is indispensable.
1793 -- Otherwise it is safe albeit redundant.
1795 Set_Is_Immediately_Visible (Spec_Id);
1798 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
1799 Set_Ekind (Body_Id, E_Subprogram_Body);
1800 Set_Scope (Body_Id, Scope (Spec_Id));
1801 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
1803 -- Case of subprogram body with no previous spec
1807 and then Comes_From_Source (Body_Id)
1808 and then not Suppress_Style_Checks (Body_Id)
1809 and then not In_Instance
1811 Style.Body_With_No_Spec (N);
1814 New_Overloaded_Entity (Body_Id);
1816 if Nkind (N) /= N_Subprogram_Body_Stub then
1817 Set_Acts_As_Spec (N);
1818 Generate_Definition (Body_Id);
1820 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
1821 Generate_Reference_To_Formals (Body_Id);
1822 Install_Formals (Body_Id);
1823 Push_Scope (Body_Id);
1827 -- Ada 2005 (AI-251): Check wrong placement of abstract interface
1828 -- primitives, and update anonymous access returns with limited views.
1830 if Ada_Version >= Ada_05
1831 and then Comes_From_Source (N)
1839 -- Check the type of the formals
1841 E := First_Entity (Body_Id);
1842 while Present (E) loop
1845 if Is_Access_Type (Etyp) then
1846 Etyp := Directly_Designated_Type (Etyp);
1849 if not Is_Class_Wide_Type (Etyp)
1850 and then Is_Interface (Etyp)
1852 Error_Msg_Name_1 := Chars (Defining_Entity (N));
1854 ("(Ada 2005) abstract interface primitives must be" &
1855 " defined in package specs", N);
1862 -- In case of functions, check the type of the result
1864 if Ekind (Body_Id) = E_Function then
1865 Etyp := Etype (Body_Id);
1867 if Is_Access_Type (Etyp) then
1868 Etyp := Directly_Designated_Type (Etyp);
1871 if not Is_Class_Wide_Type (Etyp)
1872 and then Is_Interface (Etyp)
1874 Error_Msg_Name_1 := Chars (Defining_Entity (N));
1876 ("(Ada 2005) abstract interface primitives must be" &
1877 " defined in package specs", N);
1881 -- If the return type is an anonymous access type whose
1882 -- designated type is the limited view of a class-wide type
1883 -- and the non-limited view is available. update the return
1884 -- type accordingly.
1886 Rtyp := Etype (Current_Scope);
1888 if Ekind (Rtyp) = E_Anonymous_Access_Type then
1889 Etyp := Directly_Designated_Type (Rtyp);
1891 if Is_Class_Wide_Type (Etyp)
1892 and then From_With_Type (Etyp)
1894 Set_Directly_Designated_Type
1895 (Etype (Current_Scope), Available_View (Etyp));
1901 -- If this is the proper body of a stub, we must verify that the stub
1902 -- conforms to the body, and to the previous spec if one was present.
1903 -- we know already that the body conforms to that spec. This test is
1904 -- only required for subprograms that come from source.
1906 if Nkind (Parent (N)) = N_Subunit
1907 and then Comes_From_Source (N)
1908 and then not Error_Posted (Body_Id)
1909 and then Nkind (Corresponding_Stub (Parent (N))) =
1910 N_Subprogram_Body_Stub
1913 Old_Id : constant Entity_Id :=
1915 (Specification (Corresponding_Stub (Parent (N))));
1917 Conformant : Boolean := False;
1920 if No (Spec_Id) then
1921 Check_Fully_Conformant (Body_Id, Old_Id);
1925 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
1927 if not Conformant then
1929 -- The stub was taken to be a new declaration. Indicate
1930 -- that it lacks a body.
1932 Set_Has_Completion (Old_Id, False);
1938 Set_Has_Completion (Body_Id);
1939 Check_Eliminated (Body_Id);
1941 if Nkind (N) = N_Subprogram_Body_Stub then
1944 elsif Present (Spec_Id)
1945 and then Expander_Active
1947 (Is_Always_Inlined (Spec_Id)
1948 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
1950 Build_Body_To_Inline (N, Spec_Id);
1953 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
1954 -- if its specification we have to install the private withed units.
1956 if Is_Compilation_Unit (Body_Id)
1957 and then Scope (Body_Id) = Standard_Standard
1959 Install_Private_With_Clauses (Body_Id);
1962 Check_Anonymous_Return;
1964 -- Now we can go on to analyze the body
1966 HSS := Handled_Statement_Sequence (N);
1967 Set_Actual_Subtypes (N, Current_Scope);
1968 Analyze_Declarations (Declarations (N));
1971 Process_End_Label (HSS, 't', Current_Scope);
1973 Check_Subprogram_Order (N);
1974 Set_Analyzed (Body_Id);
1976 -- If we have a separate spec, then the analysis of the declarations
1977 -- caused the entities in the body to be chained to the spec id, but
1978 -- we want them chained to the body id. Only the formal parameters
1979 -- end up chained to the spec id in this case.
1981 if Present (Spec_Id) then
1983 -- We must conform to the categorization of our spec
1985 Validate_Categorization_Dependency (N, Spec_Id);
1987 -- And if this is a child unit, the parent units must conform
1989 if Is_Child_Unit (Spec_Id) then
1990 Validate_Categorization_Dependency
1991 (Unit_Declaration_Node (Spec_Id), Spec_Id);
1994 if Present (Last_Formal) then
1996 (Last_Entity (Body_Id), Next_Entity (Last_Formal));
1997 Set_Next_Entity (Last_Formal, Empty);
1998 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1999 Set_Last_Entity (Spec_Id, Last_Formal);
2002 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2003 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2004 Set_First_Entity (Spec_Id, Empty);
2005 Set_Last_Entity (Spec_Id, Empty);
2009 -- If function, check return statements
2011 if Nkind (Body_Spec) = N_Function_Specification then
2016 if Present (Spec_Id) then
2022 if Return_Present (Id) then
2023 Check_Returns (HSS, 'F', Missing_Ret);
2026 Set_Has_Missing_Return (Id);
2029 elsif not Is_Machine_Code_Subprogram (Id)
2030 and then not Body_Deleted
2032 Error_Msg_N ("missing RETURN statement in function body", N);
2036 -- If procedure with No_Return, check returns
2038 elsif Nkind (Body_Spec) = N_Procedure_Specification
2039 and then Present (Spec_Id)
2040 and then No_Return (Spec_Id)
2042 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2045 -- Now we are going to check for variables that are never modified in
2046 -- the body of the procedure. We omit these checks if the first
2047 -- statement of the procedure raises an exception. In particular this
2048 -- deals with the common idiom of a stubbed function, which might
2049 -- appear as something like
2051 -- function F (A : Integer) return Some_Type;
2054 -- raise Program_Error;
2058 -- Here the purpose of X is simply to satisfy the (annoying)
2059 -- requirement in Ada that there be at least one return, and we
2060 -- certainly do not want to go posting warnings on X that it is not
2064 Stm : Node_Id := First (Statements (HSS));
2067 -- Skip initial labels (for one thing this occurs when we are in
2068 -- front end ZCX mode, but in any case it is irrelevant), and also
2069 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2071 while Nkind (Stm) = N_Label
2072 or else Nkind (Stm) in N_Push_xxx_Label
2077 -- Do the test on the original statement before expansion
2080 Ostm : constant Node_Id := Original_Node (Stm);
2083 -- If explicit raise statement, return with no checks
2085 if Nkind (Ostm) = N_Raise_Statement then
2088 -- Check for explicit call cases which likely raise an exception
2090 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2091 if Is_Entity_Name (Name (Ostm)) then
2093 Ent : constant Entity_Id := Entity (Name (Ostm));
2096 -- If the procedure is marked No_Return, then likely it
2097 -- raises an exception, but in any case it is not coming
2098 -- back here, so no need to check beyond the call.
2100 if Ekind (Ent) = E_Procedure
2101 and then No_Return (Ent)
2105 -- If the procedure name is Raise_Exception, then also
2106 -- assume that it raises an exception. The main target
2107 -- here is Ada.Exceptions.Raise_Exception, but this name
2108 -- is pretty evocative in any context! Note that the
2109 -- procedure in Ada.Exceptions is not marked No_Return
2110 -- because of the annoying case of the null exception Id.
2112 elsif Chars (Ent) = Name_Raise_Exception then
2121 -- Check for variables that are never modified
2127 -- If there is a separate spec, then transfer Never_Set_In_Source
2128 -- flags from out parameters to the corresponding entities in the
2129 -- body. The reason we do that is we want to post error flags on
2130 -- the body entities, not the spec entities.
2132 if Present (Spec_Id) then
2133 E1 := First_Entity (Spec_Id);
2134 while Present (E1) loop
2135 if Ekind (E1) = E_Out_Parameter then
2136 E2 := First_Entity (Body_Id);
2137 while Present (E2) loop
2138 exit when Chars (E1) = Chars (E2);
2142 if Present (E2) then
2143 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2151 -- Check references in body unless it was deleted. Note that the
2152 -- check of Body_Deleted here is not just for efficiency, it is
2153 -- necessary to avoid junk warnings on formal parameters.
2155 if not Body_Deleted then
2156 Check_References (Body_Id);
2159 end Analyze_Subprogram_Body;
2161 ------------------------------------
2162 -- Analyze_Subprogram_Declaration --
2163 ------------------------------------
2165 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2166 Designator : constant Entity_Id :=
2167 Analyze_Subprogram_Specification (Specification (N));
2168 Scop : constant Entity_Id := Current_Scope;
2170 -- Start of processing for Analyze_Subprogram_Declaration
2173 Generate_Definition (Designator);
2175 -- Check for RCI unit subprogram declarations for illegal inlined
2176 -- subprograms and subprograms having access parameter or limited
2177 -- parameter without Read and Write attributes (RM E.2.3(12-13)).
2179 Validate_RCI_Subprogram_Declaration (N);
2183 Defining_Entity (N),
2184 " Analyze subprogram spec. ");
2186 if Debug_Flag_C then
2187 Write_Str ("==== Compiling subprogram spec ");
2188 Write_Name (Chars (Designator));
2189 Write_Str (" from ");
2190 Write_Location (Sloc (N));
2194 New_Overloaded_Entity (Designator);
2195 Check_Delayed_Subprogram (Designator);
2197 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
2200 if Ada_Version >= Ada_05
2201 and then Comes_From_Source (N)
2202 and then Is_Dispatching_Operation (Designator)
2209 if Has_Controlling_Result (Designator) then
2210 Etyp := Etype (Designator);
2213 E := First_Entity (Designator);
2215 and then Is_Formal (E)
2216 and then not Is_Controlling_Formal (E)
2224 if Is_Access_Type (Etyp) then
2225 Etyp := Directly_Designated_Type (Etyp);
2228 if Is_Interface (Etyp)
2229 and then not Is_Abstract_Subprogram (Designator)
2230 and then not (Ekind (Designator) = E_Procedure
2231 and then Null_Present (Specification (N)))
2233 Error_Msg_Name_1 := Chars (Defining_Entity (N));
2235 ("(Ada 2005) interface subprogram % must be abstract or null",
2241 -- What is the following code for, it used to be
2243 -- ??? Set_Suppress_Elaboration_Checks
2244 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
2246 -- The following seems equivalent, but a bit dubious
2248 if Elaboration_Checks_Suppressed (Designator) then
2249 Set_Kill_Elaboration_Checks (Designator);
2252 if Scop /= Standard_Standard
2253 and then not Is_Child_Unit (Designator)
2255 Set_Categorization_From_Scope (Designator, Scop);
2257 -- For a compilation unit, check for library-unit pragmas
2259 Push_Scope (Designator);
2260 Set_Categorization_From_Pragmas (N);
2261 Validate_Categorization_Dependency (N, Designator);
2265 -- For a compilation unit, set body required. This flag will only be
2266 -- reset if a valid Import or Interface pragma is processed later on.
2268 if Nkind (Parent (N)) = N_Compilation_Unit then
2269 Set_Body_Required (Parent (N), True);
2271 if Ada_Version >= Ada_05
2272 and then Nkind (Specification (N)) = N_Procedure_Specification
2273 and then Null_Present (Specification (N))
2276 ("null procedure cannot be declared at library level", N);
2280 Generate_Reference_To_Formals (Designator);
2281 Check_Eliminated (Designator);
2283 -- Ada 2005: if procedure is declared with "is null" qualifier,
2284 -- it requires no body.
2286 if Nkind (Specification (N)) = N_Procedure_Specification
2287 and then Null_Present (Specification (N))
2289 Set_Has_Completion (Designator);
2290 Set_Is_Inlined (Designator);
2292 if Is_Protected_Type (Current_Scope) then
2294 ("protected operation cannot be a null procedure", N);
2297 end Analyze_Subprogram_Declaration;
2299 --------------------------------------
2300 -- Analyze_Subprogram_Specification --
2301 --------------------------------------
2303 -- Reminder: N here really is a subprogram specification (not a subprogram
2304 -- declaration). This procedure is called to analyze the specification in
2305 -- both subprogram bodies and subprogram declarations (specs).
2307 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
2308 Designator : constant Entity_Id := Defining_Entity (N);
2310 Formal_Typ : Entity_Id;
2311 Formals : constant List_Id := Parameter_Specifications (N);
2313 -- Start of processing for Analyze_Subprogram_Specification
2316 Generate_Definition (Designator);
2318 if Nkind (N) = N_Function_Specification then
2319 Set_Ekind (Designator, E_Function);
2320 Set_Mechanism (Designator, Default_Mechanism);
2323 Set_Ekind (Designator, E_Procedure);
2324 Set_Etype (Designator, Standard_Void_Type);
2327 -- Introduce new scope for analysis of the formals and of the
2330 Set_Scope (Designator, Current_Scope);
2332 if Present (Formals) then
2333 Push_Scope (Designator);
2334 Process_Formals (Formals, N);
2336 -- Ada 2005 (AI-345): Allow the overriding of interface primitives
2337 -- by subprograms which belong to a concurrent type implementing an
2338 -- interface. Set the parameter type of each controlling formal to
2339 -- the corresponding record type.
2341 if Ada_Version >= Ada_05 then
2342 Formal := First_Formal (Designator);
2343 while Present (Formal) loop
2344 Formal_Typ := Etype (Formal);
2346 if (Ekind (Formal_Typ) = E_Protected_Type
2347 or else Ekind (Formal_Typ) = E_Task_Type)
2348 and then Present (Corresponding_Record_Type (Formal_Typ))
2349 and then Present (Abstract_Interfaces
2350 (Corresponding_Record_Type (Formal_Typ)))
2353 Corresponding_Record_Type (Formal_Typ));
2356 Formal := Next_Formal (Formal);
2362 elsif Nkind (N) = N_Function_Specification then
2363 Analyze_Return_Type (N);
2366 if Nkind (N) = N_Function_Specification then
2367 if Nkind (Designator) = N_Defining_Operator_Symbol then
2368 Valid_Operator_Definition (Designator);
2371 May_Need_Actuals (Designator);
2373 -- Ada 2005 (AI-251): In case of primitives associated with abstract
2374 -- interface types the following error message will be reported later
2375 -- (see Analyze_Subprogram_Declaration).
2377 if Is_Abstract_Type (Etype (Designator))
2378 and then not Is_Interface (Etype (Designator))
2379 and then Nkind (Parent (N))
2380 /= N_Abstract_Subprogram_Declaration
2381 and then (Nkind (Parent (N)))
2382 /= N_Formal_Abstract_Subprogram_Declaration
2383 and then (Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
2384 or else not Is_Entity_Name (Name (Parent (N)))
2385 or else not Is_Abstract_Subprogram
2386 (Entity (Name (Parent (N)))))
2389 ("function that returns abstract type must be abstract", N);
2394 end Analyze_Subprogram_Specification;
2396 --------------------------
2397 -- Build_Body_To_Inline --
2398 --------------------------
2400 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
2401 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
2402 Original_Body : Node_Id;
2403 Body_To_Analyze : Node_Id;
2404 Max_Size : constant := 10;
2405 Stat_Count : Integer := 0;
2407 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
2408 -- Check for declarations that make inlining not worthwhile
2410 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
2411 -- Check for statements that make inlining not worthwhile: any tasking
2412 -- statement, nested at any level. Keep track of total number of
2413 -- elementary statements, as a measure of acceptable size.
2415 function Has_Pending_Instantiation return Boolean;
2416 -- If some enclosing body contains instantiations that appear before the
2417 -- corresponding generic body, the enclosing body has a freeze node so
2418 -- that it can be elaborated after the generic itself. This might
2419 -- conflict with subsequent inlinings, so that it is unsafe to try to
2420 -- inline in such a case.
2422 function Has_Single_Return return Boolean;
2423 -- In general we cannot inline functions that return unconstrained type.
2424 -- However, we can handle such functions if all return statements return
2425 -- a local variable that is the only declaration in the body of the
2426 -- function. In that case the call can be replaced by that local
2427 -- variable as is done for other inlined calls.
2429 procedure Remove_Pragmas;
2430 -- A pragma Unreferenced that mentions a formal parameter has no meaning
2431 -- when the body is inlined and the formals are rewritten. Remove it
2432 -- from body to inline. The analysis of the non-inlined body will handle
2433 -- the pragma properly.
2435 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
2436 -- If the body of the subprogram includes a call that returns an
2437 -- unconstrained type, the secondary stack is involved, and it
2438 -- is not worth inlining.
2440 ------------------------------
2441 -- Has_Excluded_Declaration --
2442 ------------------------------
2444 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
2447 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
2448 -- Nested subprograms make a given body ineligible for inlining, but
2449 -- we make an exception for instantiations of unchecked conversion.
2450 -- The body has not been analyzed yet, so check the name, and verify
2451 -- that the visible entity with that name is the predefined unit.
2453 -----------------------------
2454 -- Is_Unchecked_Conversion --
2455 -----------------------------
2457 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
2458 Id : constant Node_Id := Name (D);
2462 if Nkind (Id) = N_Identifier
2463 and then Chars (Id) = Name_Unchecked_Conversion
2465 Conv := Current_Entity (Id);
2467 elsif (Nkind (Id) = N_Selected_Component
2468 or else Nkind (Id) = N_Expanded_Name)
2469 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
2471 Conv := Current_Entity (Selector_Name (Id));
2477 return Present (Conv)
2478 and then Is_Predefined_File_Name
2479 (Unit_File_Name (Get_Source_Unit (Conv)))
2480 and then Is_Intrinsic_Subprogram (Conv);
2481 end Is_Unchecked_Conversion;
2483 -- Start of processing for Has_Excluded_Declaration
2488 while Present (D) loop
2489 if (Nkind (D) = N_Function_Instantiation
2490 and then not Is_Unchecked_Conversion (D))
2491 or else Nkind (D) = N_Protected_Type_Declaration
2492 or else Nkind (D) = N_Package_Declaration
2493 or else Nkind (D) = N_Package_Instantiation
2494 or else Nkind (D) = N_Subprogram_Body
2495 or else Nkind (D) = N_Procedure_Instantiation
2496 or else Nkind (D) = N_Task_Type_Declaration
2499 ("cannot inline & (non-allowed declaration)?", D, Subp);
2507 end Has_Excluded_Declaration;
2509 ----------------------------
2510 -- Has_Excluded_Statement --
2511 ----------------------------
2513 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
2519 while Present (S) loop
2520 Stat_Count := Stat_Count + 1;
2522 if Nkind (S) = N_Abort_Statement
2523 or else Nkind (S) = N_Asynchronous_Select
2524 or else Nkind (S) = N_Conditional_Entry_Call
2525 or else Nkind (S) = N_Delay_Relative_Statement
2526 or else Nkind (S) = N_Delay_Until_Statement
2527 or else Nkind (S) = N_Selective_Accept
2528 or else Nkind (S) = N_Timed_Entry_Call
2531 ("cannot inline & (non-allowed statement)?", S, Subp);
2534 elsif Nkind (S) = N_Block_Statement then
2535 if Present (Declarations (S))
2536 and then Has_Excluded_Declaration (Declarations (S))
2540 elsif Present (Handled_Statement_Sequence (S))
2543 (Exception_Handlers (Handled_Statement_Sequence (S)))
2545 Has_Excluded_Statement
2546 (Statements (Handled_Statement_Sequence (S))))
2551 elsif Nkind (S) = N_Case_Statement then
2552 E := First (Alternatives (S));
2553 while Present (E) loop
2554 if Has_Excluded_Statement (Statements (E)) then
2561 elsif Nkind (S) = N_If_Statement then
2562 if Has_Excluded_Statement (Then_Statements (S)) then
2566 if Present (Elsif_Parts (S)) then
2567 E := First (Elsif_Parts (S));
2568 while Present (E) loop
2569 if Has_Excluded_Statement (Then_Statements (E)) then
2576 if Present (Else_Statements (S))
2577 and then Has_Excluded_Statement (Else_Statements (S))
2582 elsif Nkind (S) = N_Loop_Statement
2583 and then Has_Excluded_Statement (Statements (S))
2592 end Has_Excluded_Statement;
2594 -------------------------------
2595 -- Has_Pending_Instantiation --
2596 -------------------------------
2598 function Has_Pending_Instantiation return Boolean is
2603 while Present (S) loop
2604 if Is_Compilation_Unit (S)
2605 or else Is_Child_Unit (S)
2608 elsif Ekind (S) = E_Package
2609 and then Has_Forward_Instantiation (S)
2618 end Has_Pending_Instantiation;
2620 ------------------------
2621 -- Has_Single_Return --
2622 ------------------------
2624 function Has_Single_Return return Boolean is
2625 Return_Statement : Node_Id := Empty;
2627 function Check_Return (N : Node_Id) return Traverse_Result;
2633 function Check_Return (N : Node_Id) return Traverse_Result is
2635 if Nkind (N) = N_Simple_Return_Statement then
2636 if Present (Expression (N))
2637 and then Is_Entity_Name (Expression (N))
2639 if No (Return_Statement) then
2640 Return_Statement := N;
2643 elsif Chars (Expression (N)) =
2644 Chars (Expression (Return_Statement))
2653 -- Expression has wrong form
2663 function Check_All_Returns is new Traverse_Func (Check_Return);
2665 -- Start of processing for Has_Single_Return
2668 return Check_All_Returns (N) = OK
2669 and then Present (Declarations (N))
2670 and then Present (First (Declarations (N)))
2671 and then Chars (Expression (Return_Statement)) =
2672 Chars (Defining_Identifier (First (Declarations (N))));
2673 end Has_Single_Return;
2675 --------------------
2676 -- Remove_Pragmas --
2677 --------------------
2679 procedure Remove_Pragmas is
2684 Decl := First (Declarations (Body_To_Analyze));
2685 while Present (Decl) loop
2688 if Nkind (Decl) = N_Pragma
2689 and then Chars (Decl) = Name_Unreferenced
2698 --------------------------
2699 -- Uses_Secondary_Stack --
2700 --------------------------
2702 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
2703 function Check_Call (N : Node_Id) return Traverse_Result;
2704 -- Look for function calls that return an unconstrained type
2710 function Check_Call (N : Node_Id) return Traverse_Result is
2712 if Nkind (N) = N_Function_Call
2713 and then Is_Entity_Name (Name (N))
2714 and then Is_Composite_Type (Etype (Entity (Name (N))))
2715 and then not Is_Constrained (Etype (Entity (Name (N))))
2718 ("cannot inline & (call returns unconstrained type)?",
2726 function Check_Calls is new Traverse_Func (Check_Call);
2729 return Check_Calls (Bod) = Abandon;
2730 end Uses_Secondary_Stack;
2732 -- Start of processing for Build_Body_To_Inline
2735 if Nkind (Decl) = N_Subprogram_Declaration
2736 and then Present (Body_To_Inline (Decl))
2738 return; -- Done already.
2740 -- Functions that return unconstrained composite types require
2741 -- secondary stack handling, and cannot currently be inlined, unless
2742 -- all return statements return a local variable that is the first
2743 -- local declaration in the body.
2745 elsif Ekind (Subp) = E_Function
2746 and then not Is_Scalar_Type (Etype (Subp))
2747 and then not Is_Access_Type (Etype (Subp))
2748 and then not Is_Constrained (Etype (Subp))
2750 if not Has_Single_Return then
2752 ("cannot inline & (unconstrained return type)?", N, Subp);
2756 -- Ditto for functions that return controlled types, where controlled
2757 -- actions interfere in complex ways with inlining.
2759 elsif Ekind (Subp) = E_Function
2760 and then Controlled_Type (Etype (Subp))
2763 ("cannot inline & (controlled return type)?", N, Subp);
2767 if Present (Declarations (N))
2768 and then Has_Excluded_Declaration (Declarations (N))
2773 if Present (Handled_Statement_Sequence (N)) then
2774 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
2776 ("cannot inline& (exception handler)?",
2777 First (Exception_Handlers (Handled_Statement_Sequence (N))),
2781 Has_Excluded_Statement
2782 (Statements (Handled_Statement_Sequence (N)))
2788 -- We do not inline a subprogram that is too large, unless it is
2789 -- marked Inline_Always. This pragma does not suppress the other
2790 -- checks on inlining (forbidden declarations, handlers, etc).
2792 if Stat_Count > Max_Size
2793 and then not Is_Always_Inlined (Subp)
2795 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
2799 if Has_Pending_Instantiation then
2801 ("cannot inline& (forward instance within enclosing body)?",
2806 -- Within an instance, the body to inline must be treated as a nested
2807 -- generic, so that the proper global references are preserved.
2810 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
2811 Original_Body := Copy_Generic_Node (N, Empty, True);
2813 Original_Body := Copy_Separate_Tree (N);
2816 -- We need to capture references to the formals in order to substitute
2817 -- the actuals at the point of inlining, i.e. instantiation. To treat
2818 -- the formals as globals to the body to inline, we nest it within
2819 -- a dummy parameterless subprogram, declared within the real one.
2820 -- To avoid generating an internal name (which is never public, and
2821 -- which affects serial numbers of other generated names), we use
2822 -- an internal symbol that cannot conflict with user declarations.
2824 Set_Parameter_Specifications (Specification (Original_Body), No_List);
2825 Set_Defining_Unit_Name
2826 (Specification (Original_Body),
2827 Make_Defining_Identifier (Sloc (N), Name_uParent));
2828 Set_Corresponding_Spec (Original_Body, Empty);
2830 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
2832 -- Set return type of function, which is also global and does not need
2835 if Ekind (Subp) = E_Function then
2836 Set_Result_Definition (Specification (Body_To_Analyze),
2837 New_Occurrence_Of (Etype (Subp), Sloc (N)));
2840 if No (Declarations (N)) then
2841 Set_Declarations (N, New_List (Body_To_Analyze));
2843 Append (Body_To_Analyze, Declarations (N));
2846 Expander_Mode_Save_And_Set (False);
2849 Analyze (Body_To_Analyze);
2850 Push_Scope (Defining_Entity (Body_To_Analyze));
2851 Save_Global_References (Original_Body);
2853 Remove (Body_To_Analyze);
2855 Expander_Mode_Restore;
2861 -- If secondary stk used there is no point in inlining. We have
2862 -- already issued the warning in this case, so nothing to do.
2864 if Uses_Secondary_Stack (Body_To_Analyze) then
2868 Set_Body_To_Inline (Decl, Original_Body);
2869 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
2870 Set_Is_Inlined (Subp);
2871 end Build_Body_To_Inline;
2877 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
2879 -- Do not emit warning if this is a predefined unit which is not
2880 -- the main unit. With validity checks enabled, some predefined
2881 -- subprograms may contain nested subprograms and become ineligible
2884 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
2885 and then not In_Extended_Main_Source_Unit (Subp)
2889 elsif Is_Always_Inlined (Subp) then
2891 -- Remove last character (question mark) to make this into an error,
2892 -- because the Inline_Always pragma cannot be obeyed.
2894 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
2896 elsif Ineffective_Inline_Warnings then
2897 Error_Msg_NE (Msg, N, Subp);
2901 -----------------------
2902 -- Check_Conformance --
2903 -----------------------
2905 procedure Check_Conformance
2906 (New_Id : Entity_Id;
2908 Ctype : Conformance_Type;
2910 Conforms : out Boolean;
2911 Err_Loc : Node_Id := Empty;
2912 Get_Inst : Boolean := False;
2913 Skip_Controlling_Formals : Boolean := False)
2915 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
2916 -- Post error message for conformance error on given node. Two messages
2917 -- are output. The first points to the previous declaration with a
2918 -- general "no conformance" message. The second is the detailed reason,
2919 -- supplied as Msg. The parameter N provide information for a possible
2920 -- & insertion in the message, and also provides the location for
2921 -- posting the message in the absence of a specified Err_Loc location.
2923 -----------------------
2924 -- Conformance_Error --
2925 -----------------------
2927 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
2934 if No (Err_Loc) then
2940 Error_Msg_Sloc := Sloc (Old_Id);
2943 when Type_Conformant =>
2945 ("not type conformant with declaration#!", Enode);
2947 when Mode_Conformant =>
2948 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2950 ("not mode conformant with operation inherited#!",
2954 ("not mode conformant with declaration#!", Enode);
2957 when Subtype_Conformant =>
2958 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2960 ("not subtype conformant with operation inherited#!",
2964 ("not subtype conformant with declaration#!", Enode);
2967 when Fully_Conformant =>
2968 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
2970 ("not fully conformant with operation inherited#!",
2974 ("not fully conformant with declaration#!", Enode);
2978 Error_Msg_NE (Msg, Enode, N);
2980 end Conformance_Error;
2984 Old_Type : constant Entity_Id := Etype (Old_Id);
2985 New_Type : constant Entity_Id := Etype (New_Id);
2986 Old_Formal : Entity_Id;
2987 New_Formal : Entity_Id;
2988 Access_Types_Match : Boolean;
2989 Old_Formal_Base : Entity_Id;
2990 New_Formal_Base : Entity_Id;
2992 -- Start of processing for Check_Conformance
2997 -- We need a special case for operators, since they don't appear
3000 if Ctype = Type_Conformant then
3001 if Ekind (New_Id) = E_Operator
3002 and then Operator_Matches_Spec (New_Id, Old_Id)
3008 -- If both are functions/operators, check return types conform
3010 if Old_Type /= Standard_Void_Type
3011 and then New_Type /= Standard_Void_Type
3013 if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3014 Conformance_Error ("\return type does not match!", New_Id);
3018 -- Ada 2005 (AI-231): In case of anonymous access types check the
3019 -- null-exclusion and access-to-constant attributes match.
3021 if Ada_Version >= Ada_05
3022 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
3024 (Can_Never_Be_Null (Old_Type)
3025 /= Can_Never_Be_Null (New_Type)
3026 or else Is_Access_Constant (Etype (Old_Type))
3027 /= Is_Access_Constant (Etype (New_Type)))
3029 Conformance_Error ("\return type does not match!", New_Id);
3033 -- If either is a function/operator and the other isn't, error
3035 elsif Old_Type /= Standard_Void_Type
3036 or else New_Type /= Standard_Void_Type
3038 Conformance_Error ("\functions can only match functions!", New_Id);
3042 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
3043 -- If this is a renaming as body, refine error message to indicate that
3044 -- the conflict is with the original declaration. If the entity is not
3045 -- frozen, the conventions don't have to match, the one of the renamed
3046 -- entity is inherited.
3048 if Ctype >= Subtype_Conformant then
3049 if Convention (Old_Id) /= Convention (New_Id) then
3051 if not Is_Frozen (New_Id) then
3054 elsif Present (Err_Loc)
3055 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
3056 and then Present (Corresponding_Spec (Err_Loc))
3058 Error_Msg_Name_1 := Chars (New_Id);
3060 Name_Ada + Convention_Id'Pos (Convention (New_Id));
3062 Conformance_Error ("\prior declaration for% has convention %!");
3065 Conformance_Error ("\calling conventions do not match!");
3070 elsif Is_Formal_Subprogram (Old_Id)
3071 or else Is_Formal_Subprogram (New_Id)
3073 Conformance_Error ("\formal subprograms not allowed!");
3078 -- Deal with parameters
3080 -- Note: we use the entity information, rather than going directly
3081 -- to the specification in the tree. This is not only simpler, but
3082 -- absolutely necessary for some cases of conformance tests between
3083 -- operators, where the declaration tree simply does not exist!
3085 Old_Formal := First_Formal (Old_Id);
3086 New_Formal := First_Formal (New_Id);
3088 while Present (Old_Formal) and then Present (New_Formal) loop
3089 if Is_Controlling_Formal (Old_Formal)
3090 and then Is_Controlling_Formal (New_Formal)
3091 and then Skip_Controlling_Formals
3093 goto Skip_Controlling_Formal;
3096 if Ctype = Fully_Conformant then
3098 -- Names must match. Error message is more accurate if we do
3099 -- this before checking that the types of the formals match.
3101 if Chars (Old_Formal) /= Chars (New_Formal) then
3102 Conformance_Error ("\name & does not match!", New_Formal);
3104 -- Set error posted flag on new formal as well to stop
3105 -- junk cascaded messages in some cases.
3107 Set_Error_Posted (New_Formal);
3112 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
3113 -- case occurs whenever a subprogram is being renamed and one of its
3114 -- parameters imposes a null exclusion. For example:
3116 -- type T is null record;
3117 -- type Acc_T is access T;
3118 -- subtype Acc_T_Sub is Acc_T;
3120 -- procedure P (Obj : not null Acc_T_Sub); -- itype
3121 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
3124 Old_Formal_Base := Etype (Old_Formal);
3125 New_Formal_Base := Etype (New_Formal);
3128 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
3129 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
3132 Access_Types_Match := Ada_Version >= Ada_05
3134 -- Ensure that this rule is only applied when New_Id is a
3135 -- renaming of Old_Id.
3137 and then Nkind (Parent (Parent (New_Id))) =
3138 N_Subprogram_Renaming_Declaration
3139 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
3140 and then Present (Entity (Name (Parent (Parent (New_Id)))))
3141 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
3143 -- Now handle the allowed access-type case
3145 and then Is_Access_Type (Old_Formal_Base)
3146 and then Is_Access_Type (New_Formal_Base)
3148 -- The type kinds must match. The only exception occurs with
3149 -- multiple generics of the form:
3152 -- type F is private; type A is private;
3153 -- type F_Ptr is access F; type A_Ptr is access A;
3154 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
3155 -- package F_Pack is ... package A_Pack is
3156 -- package F_Inst is
3157 -- new F_Pack (A, A_Ptr, A_P);
3159 -- When checking for conformance between the parameters of A_P
3160 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
3161 -- because the compiler has transformed A_Ptr into a subtype of
3162 -- F_Ptr. We catch this case in the code below.
3164 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
3166 (Is_Generic_Type (Old_Formal_Base)
3167 and then Is_Generic_Type (New_Formal_Base)
3168 and then Is_Internal (New_Formal_Base)
3169 and then Etype (Etype (New_Formal_Base)) =
3171 and then Directly_Designated_Type (Old_Formal_Base) =
3172 Directly_Designated_Type (New_Formal_Base)
3173 and then ((Is_Itype (Old_Formal_Base)
3174 and then Can_Never_Be_Null (Old_Formal_Base))
3176 (Is_Itype (New_Formal_Base)
3177 and then Can_Never_Be_Null (New_Formal_Base)));
3179 -- Types must always match. In the visible part of an instance,
3180 -- usual overloading rules for dispatching operations apply, and
3181 -- we check base types (not the actual subtypes).
3183 if In_Instance_Visible_Part
3184 and then Is_Dispatching_Operation (New_Id)
3186 if not Conforming_Types
3187 (T1 => Base_Type (Etype (Old_Formal)),
3188 T2 => Base_Type (Etype (New_Formal)),
3190 Get_Inst => Get_Inst)
3191 and then not Access_Types_Match
3193 Conformance_Error ("\type of & does not match!", New_Formal);
3197 elsif not Conforming_Types
3198 (T1 => Old_Formal_Base,
3199 T2 => New_Formal_Base,
3201 Get_Inst => Get_Inst)
3202 and then not Access_Types_Match
3204 Conformance_Error ("\type of & does not match!", New_Formal);
3208 -- For mode conformance, mode must match
3210 if Ctype >= Mode_Conformant then
3211 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
3212 Conformance_Error ("\mode of & does not match!", New_Formal);
3215 -- Part of mode conformance for access types is having the same
3216 -- constant modifier.
3218 elsif Access_Types_Match
3219 and then Is_Access_Constant (Old_Formal_Base) /=
3220 Is_Access_Constant (New_Formal_Base)
3223 ("\constant modifier does not match!", New_Formal);
3228 if Ctype >= Subtype_Conformant then
3230 -- Ada 2005 (AI-231): In case of anonymous access types check
3231 -- the null-exclusion and access-to-constant attributes must
3234 if Ada_Version >= Ada_05
3235 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
3236 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
3238 (Can_Never_Be_Null (Old_Formal) /=
3239 Can_Never_Be_Null (New_Formal)
3241 Is_Access_Constant (Etype (Old_Formal)) /=
3242 Is_Access_Constant (Etype (New_Formal)))
3244 -- It is allowed to omit the null-exclusion in case of stream
3245 -- attribute subprograms. We recognize stream subprograms
3246 -- through their TSS-generated suffix.
3249 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
3251 if TSS_Name /= TSS_Stream_Read
3252 and then TSS_Name /= TSS_Stream_Write
3253 and then TSS_Name /= TSS_Stream_Input
3254 and then TSS_Name /= TSS_Stream_Output
3257 ("\type of & does not match!", New_Formal);
3264 -- Full conformance checks
3266 if Ctype = Fully_Conformant then
3268 -- We have checked already that names match
3270 if Parameter_Mode (Old_Formal) = E_In_Parameter then
3272 -- Check default expressions for in parameters
3275 NewD : constant Boolean :=
3276 Present (Default_Value (New_Formal));
3277 OldD : constant Boolean :=
3278 Present (Default_Value (Old_Formal));
3280 if NewD or OldD then
3282 -- The old default value has been analyzed because the
3283 -- current full declaration will have frozen everything
3284 -- before. The new default value has not been analyzed,
3285 -- so analyze it now before we check for conformance.
3288 Push_Scope (New_Id);
3289 Analyze_Per_Use_Expression
3290 (Default_Value (New_Formal), Etype (New_Formal));
3294 if not (NewD and OldD)
3295 or else not Fully_Conformant_Expressions
3296 (Default_Value (Old_Formal),
3297 Default_Value (New_Formal))
3300 ("\default expression for & does not match!",
3309 -- A couple of special checks for Ada 83 mode. These checks are
3310 -- skipped if either entity is an operator in package Standard,
3311 -- or if either old or new instance is not from the source program.
3313 if Ada_Version = Ada_83
3314 and then Sloc (Old_Id) > Standard_Location
3315 and then Sloc (New_Id) > Standard_Location
3316 and then Comes_From_Source (Old_Id)
3317 and then Comes_From_Source (New_Id)
3320 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
3321 New_Param : constant Node_Id := Declaration_Node (New_Formal);
3324 -- Explicit IN must be present or absent in both cases. This
3325 -- test is required only in the full conformance case.
3327 if In_Present (Old_Param) /= In_Present (New_Param)
3328 and then Ctype = Fully_Conformant
3331 ("\(Ada 83) IN must appear in both declarations",
3336 -- Grouping (use of comma in param lists) must be the same
3337 -- This is where we catch a misconformance like:
3340 -- A : Integer; B : Integer
3342 -- which are represented identically in the tree except
3343 -- for the setting of the flags More_Ids and Prev_Ids.
3345 if More_Ids (Old_Param) /= More_Ids (New_Param)
3346 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
3349 ("\grouping of & does not match!", New_Formal);
3355 -- This label is required when skipping controlling formals
3357 <<Skip_Controlling_Formal>>
3359 Next_Formal (Old_Formal);
3360 Next_Formal (New_Formal);
3363 if Present (Old_Formal) then
3364 Conformance_Error ("\too few parameters!");
3367 elsif Present (New_Formal) then
3368 Conformance_Error ("\too many parameters!", New_Formal);
3371 end Check_Conformance;
3373 -----------------------
3374 -- Check_Conventions --
3375 -----------------------
3377 procedure Check_Conventions (Typ : Entity_Id) is
3379 function Skip_Check (Op : Entity_Id) return Boolean;
3380 pragma Inline (Skip_Check);
3381 -- A small optimization: skip the predefined dispatching operations,
3382 -- since they always have the same convention. Also do not consider
3383 -- abstract primitives since those are left by an erroneous overriding.
3384 -- This function returns True for any operation that is thus exempted
3385 -- exempted from checking.
3387 procedure Check_Convention
3389 Search_From : Elmt_Id);
3390 -- Verify that the convention of inherited dispatching operation Op is
3391 -- consistent among all subprograms it overrides. In order to minimize
3392 -- the search, Search_From is utilized to designate a specific point in
3393 -- the list rather than iterating over the whole list once more.
3395 ----------------------
3396 -- Check_Convention --
3397 ----------------------
3399 procedure Check_Convention
3401 Search_From : Elmt_Id)
3403 procedure Error_Msg_Operation (Op : Entity_Id);
3404 -- Emit a continuation to an error message depicting the kind, name,
3405 -- convention and source location of subprogram Op.
3407 -------------------------
3408 -- Error_Msg_Operation --
3409 -------------------------
3411 procedure Error_Msg_Operation (Op : Entity_Id) is
3413 Error_Msg_Name_1 := Chars (Op);
3415 -- Error messages of primitive subprograms do not contain a
3416 -- convention attribute since the convention may have been first
3417 -- inherited from a parent subprogram, then changed by a pragma.
3419 if Comes_From_Source (Op) then
3420 Error_Msg_Sloc := Sloc (Op);
3422 ("\ primitive % defined #", Typ);
3425 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
3427 if Present (Abstract_Interface_Alias (Op)) then
3428 Error_Msg_Sloc := Sloc (Abstract_Interface_Alias (Op));
3429 Error_Msg_N ("\\overridden operation % with " &
3430 "convention % defined #", Typ);
3432 else pragma Assert (Present (Alias (Op)));
3433 Error_Msg_Sloc := Sloc (Alias (Op));
3434 Error_Msg_N ("\\inherited operation % with " &
3435 "convention % defined #", Typ);
3438 end Error_Msg_Operation;
3442 Second_Prim_Op : Entity_Id;
3443 Second_Prim_Op_Elmt : Elmt_Id;
3445 -- Start of processing for Check_Convention
3448 Second_Prim_Op_Elmt := Next_Elmt (Search_From);
3449 while Present (Second_Prim_Op_Elmt) loop
3450 Second_Prim_Op := Node (Second_Prim_Op_Elmt);
3452 if not Skip_Check (Second_Prim_Op)
3453 and then Chars (Second_Prim_Op) = Chars (Op)
3454 and then Type_Conformant (Second_Prim_Op, Op)
3455 and then Convention (Second_Prim_Op) /= Convention (Op)
3458 ("inconsistent conventions in primitive operations", Typ);
3460 Error_Msg_Operation (Op);
3461 Error_Msg_Operation (Second_Prim_Op);
3463 -- Avoid cascading errors
3468 Next_Elmt (Second_Prim_Op_Elmt);
3470 end Check_Convention;
3476 function Skip_Check (Op : Entity_Id) return Boolean is
3478 return Is_Predefined_Dispatching_Operation (Op)
3479 or else Is_Abstract_Subprogram (Op);
3484 Prim_Op : Entity_Id;
3485 Prim_Op_Elmt : Elmt_Id;
3487 -- Start of processing for Check_Conventions
3490 -- The algorithm checks every overriding dispatching operation against
3491 -- all the corresponding overridden dispatching operations, detecting
3492 -- differences in coventions.
3494 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
3495 while Present (Prim_Op_Elmt) loop
3496 Prim_Op := Node (Prim_Op_Elmt);
3498 -- A small optimization: skip the predefined dispatching operations
3499 -- since they always have the same convention. Also avoid processing
3500 -- of abstract primitives left from an erroneous overriding.
3502 if not Skip_Check (Prim_Op) then
3505 Search_From => Prim_Op_Elmt);
3508 Next_Elmt (Prim_Op_Elmt);
3510 end Check_Conventions;
3512 ------------------------------
3513 -- Check_Delayed_Subprogram --
3514 ------------------------------
3516 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
3519 procedure Possible_Freeze (T : Entity_Id);
3520 -- T is the type of either a formal parameter or of the return type.
3521 -- If T is not yet frozen and needs a delayed freeze, then the
3522 -- subprogram itself must be delayed.
3524 ---------------------
3525 -- Possible_Freeze --
3526 ---------------------
3528 procedure Possible_Freeze (T : Entity_Id) is
3530 if Has_Delayed_Freeze (T)
3531 and then not Is_Frozen (T)
3533 Set_Has_Delayed_Freeze (Designator);
3535 elsif Is_Access_Type (T)
3536 and then Has_Delayed_Freeze (Designated_Type (T))
3537 and then not Is_Frozen (Designated_Type (T))
3539 Set_Has_Delayed_Freeze (Designator);
3541 end Possible_Freeze;
3543 -- Start of processing for Check_Delayed_Subprogram
3546 -- Never need to freeze abstract subprogram
3548 if Ekind (Designator) /= E_Subprogram_Type
3549 and then Is_Abstract_Subprogram (Designator)
3553 -- Need delayed freeze if return type itself needs a delayed
3554 -- freeze and is not yet frozen.
3556 Possible_Freeze (Etype (Designator));
3557 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
3559 -- Need delayed freeze if any of the formal types themselves need
3560 -- a delayed freeze and are not yet frozen.
3562 F := First_Formal (Designator);
3563 while Present (F) loop
3564 Possible_Freeze (Etype (F));
3565 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
3570 -- Mark functions that return by reference. Note that it cannot be
3571 -- done for delayed_freeze subprograms because the underlying
3572 -- returned type may not be known yet (for private types)
3574 if not Has_Delayed_Freeze (Designator)
3575 and then Expander_Active
3578 Typ : constant Entity_Id := Etype (Designator);
3579 Utyp : constant Entity_Id := Underlying_Type (Typ);
3582 if Is_Inherently_Limited_Type (Typ) then
3583 Set_Returns_By_Ref (Designator);
3585 elsif Present (Utyp) and then CW_Or_Controlled_Type (Utyp) then
3586 Set_Returns_By_Ref (Designator);
3590 end Check_Delayed_Subprogram;
3592 ------------------------------------
3593 -- Check_Discriminant_Conformance --
3594 ------------------------------------
3596 procedure Check_Discriminant_Conformance
3601 Old_Discr : Entity_Id := First_Discriminant (Prev);
3602 New_Discr : Node_Id := First (Discriminant_Specifications (N));
3603 New_Discr_Id : Entity_Id;
3604 New_Discr_Type : Entity_Id;
3606 procedure Conformance_Error (Msg : String; N : Node_Id);
3607 -- Post error message for conformance error on given node. Two messages
3608 -- are output. The first points to the previous declaration with a
3609 -- general "no conformance" message. The second is the detailed reason,
3610 -- supplied as Msg. The parameter N provide information for a possible
3611 -- & insertion in the message.
3613 -----------------------
3614 -- Conformance_Error --
3615 -----------------------
3617 procedure Conformance_Error (Msg : String; N : Node_Id) is
3619 Error_Msg_Sloc := Sloc (Prev_Loc);
3620 Error_Msg_N ("not fully conformant with declaration#!", N);
3621 Error_Msg_NE (Msg, N, N);
3622 end Conformance_Error;
3624 -- Start of processing for Check_Discriminant_Conformance
3627 while Present (Old_Discr) and then Present (New_Discr) loop
3629 New_Discr_Id := Defining_Identifier (New_Discr);
3631 -- The subtype mark of the discriminant on the full type has not
3632 -- been analyzed so we do it here. For an access discriminant a new
3635 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
3637 Access_Definition (N, Discriminant_Type (New_Discr));
3640 Analyze (Discriminant_Type (New_Discr));
3641 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
3644 if not Conforming_Types
3645 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
3647 Conformance_Error ("type of & does not match!", New_Discr_Id);
3650 -- Treat the new discriminant as an occurrence of the old one,
3651 -- for navigation purposes, and fill in some semantic
3652 -- information, for completeness.
3654 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
3655 Set_Etype (New_Discr_Id, Etype (Old_Discr));
3656 Set_Scope (New_Discr_Id, Scope (Old_Discr));
3661 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
3662 Conformance_Error ("name & does not match!", New_Discr_Id);
3666 -- Default expressions must match
3669 NewD : constant Boolean :=
3670 Present (Expression (New_Discr));
3671 OldD : constant Boolean :=
3672 Present (Expression (Parent (Old_Discr)));
3675 if NewD or OldD then
3677 -- The old default value has been analyzed and expanded,
3678 -- because the current full declaration will have frozen
3679 -- everything before. The new default values have not been
3680 -- expanded, so expand now to check conformance.
3683 Analyze_Per_Use_Expression
3684 (Expression (New_Discr), New_Discr_Type);
3687 if not (NewD and OldD)
3688 or else not Fully_Conformant_Expressions
3689 (Expression (Parent (Old_Discr)),
3690 Expression (New_Discr))
3694 ("default expression for & does not match!",
3701 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
3703 if Ada_Version = Ada_83 then
3705 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
3708 -- Grouping (use of comma in param lists) must be the same
3709 -- This is where we catch a misconformance like:
3712 -- A : Integer; B : Integer
3714 -- which are represented identically in the tree except
3715 -- for the setting of the flags More_Ids and Prev_Ids.
3717 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
3718 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
3721 ("grouping of & does not match!", New_Discr_Id);
3727 Next_Discriminant (Old_Discr);
3731 if Present (Old_Discr) then
3732 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
3735 elsif Present (New_Discr) then
3737 ("too many discriminants!", Defining_Identifier (New_Discr));
3740 end Check_Discriminant_Conformance;
3742 ----------------------------
3743 -- Check_Fully_Conformant --
3744 ----------------------------
3746 procedure Check_Fully_Conformant
3747 (New_Id : Entity_Id;
3749 Err_Loc : Node_Id := Empty)
3754 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
3755 end Check_Fully_Conformant;
3757 ---------------------------
3758 -- Check_Mode_Conformant --
3759 ---------------------------
3761 procedure Check_Mode_Conformant
3762 (New_Id : Entity_Id;
3764 Err_Loc : Node_Id := Empty;
3765 Get_Inst : Boolean := False)
3771 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
3772 end Check_Mode_Conformant;
3774 --------------------------------
3775 -- Check_Overriding_Indicator --
3776 --------------------------------
3778 procedure Check_Overriding_Indicator
3780 Overridden_Subp : Entity_Id;
3781 Is_Primitive : Boolean)
3787 -- No overriding indicator for literals
3789 if Ekind (Subp) = E_Enumeration_Literal then
3792 elsif Ekind (Subp) = E_Entry then
3793 Decl := Parent (Subp);
3796 Decl := Unit_Declaration_Node (Subp);
3799 if Nkind (Decl) = N_Subprogram_Body
3800 or else Nkind (Decl) = N_Subprogram_Body_Stub
3801 or else Nkind (Decl) = N_Subprogram_Declaration
3802 or else Nkind (Decl) = N_Abstract_Subprogram_Declaration
3803 or else Nkind (Decl) = N_Subprogram_Renaming_Declaration
3805 Spec := Specification (Decl);
3807 elsif Nkind (Decl) = N_Entry_Declaration then
3814 if Present (Overridden_Subp) then
3815 if Must_Not_Override (Spec) then
3816 Error_Msg_Sloc := Sloc (Overridden_Subp);
3818 if Ekind (Subp) = E_Entry then
3820 ("entry & overrides inherited operation #", Spec, Subp);
3823 ("subprogram & overrides inherited operation #", Spec, Subp);
3827 -- If Subp is an operator, it may override a predefined operation.
3828 -- In that case overridden_subp is empty because of our implicit
3829 -- representation for predefined operators. We have to check whether the
3830 -- signature of Subp matches that of a predefined operator. Note that
3831 -- first argument provides the name of the operator, and the second
3832 -- argument the signature that may match that of a standard operation.
3834 elsif Nkind (Subp) = N_Defining_Operator_Symbol
3835 and then Must_Not_Override (Spec)
3837 if Operator_Matches_Spec (Subp, Subp) then
3839 ("subprogram & overrides predefined operator ",
3843 elsif Must_Override (Spec) then
3844 if Ekind (Subp) = E_Entry then
3845 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
3847 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
3848 if not Operator_Matches_Spec (Subp, Subp) then
3850 ("subprogram & is not overriding", Spec, Subp);
3854 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
3857 -- If the operation is marked "not overriding" and it's not primitive
3858 -- then an error is issued, unless this is an operation of a task or
3859 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
3860 -- has been specified have already been checked above.
3862 elsif Must_Not_Override (Spec)
3863 and then not Is_Primitive
3864 and then Ekind (Subp) /= E_Entry
3865 and then Ekind (Scope (Subp)) /= E_Protected_Type
3868 ("overriding indicator only allowed if subprogram is primitive",
3873 end Check_Overriding_Indicator;
3879 -- Note: this procedure needs to know far too much about how the expander
3880 -- messes with exceptions. The use of the flag Exception_Junk and the
3881 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
3882 -- works, but is not very clean. It would be better if the expansion
3883 -- routines would leave Original_Node working nicely, and we could use
3884 -- Original_Node here to ignore all the peculiar expander messing ???
3886 procedure Check_Returns
3890 Proc : Entity_Id := Empty)
3894 procedure Check_Statement_Sequence (L : List_Id);
3895 -- Internal recursive procedure to check a list of statements for proper
3896 -- termination by a return statement (or a transfer of control or a
3897 -- compound statement that is itself internally properly terminated).
3899 ------------------------------
3900 -- Check_Statement_Sequence --
3901 ------------------------------
3903 procedure Check_Statement_Sequence (L : List_Id) is
3908 Raise_Exception_Call : Boolean;
3909 -- Set True if statement sequence terminated by Raise_Exception call
3910 -- or a Reraise_Occurrence call.
3913 Raise_Exception_Call := False;
3915 -- Get last real statement
3917 Last_Stm := Last (L);
3919 -- Deal with digging out exception handler statement sequences that
3920 -- have been transformed by the local raise to goto optimization.
3921 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
3922 -- optimization has occurred, we are looking at something like:
3925 -- original stmts in block
3929 -- goto L1; | omitted if No_Exception_Propagation
3934 -- goto L3; -- skip handler when exception not raised
3936 -- <<L1>> -- target label for local exception
3950 -- and what we have to do is to dig out the estmts1 and estmts2
3951 -- sequences (which were the original sequences of statements in
3952 -- the exception handlers) and check them.
3954 if Nkind (Last_Stm) = N_Label
3955 and then Exception_Junk (Last_Stm)
3961 exit when Nkind (Stm) /= N_Block_Statement;
3962 exit when not Exception_Junk (Stm);
3965 exit when Nkind (Stm) /= N_Label;
3966 exit when not Exception_Junk (Stm);
3967 Check_Statement_Sequence
3968 (Statements (Handled_Statement_Sequence (Next (Stm))));
3973 exit when Nkind (Stm) /= N_Goto_Statement;
3974 exit when not Exception_Junk (Stm);
3978 -- Don't count pragmas
3980 while Nkind (Last_Stm) = N_Pragma
3982 -- Don't count call to SS_Release (can happen after Raise_Exception)
3985 (Nkind (Last_Stm) = N_Procedure_Call_Statement
3987 Nkind (Name (Last_Stm)) = N_Identifier
3989 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
3991 -- Don't count exception junk
3994 ((Nkind (Last_Stm) = N_Goto_Statement
3995 or else Nkind (Last_Stm) = N_Label
3996 or else Nkind (Last_Stm) = N_Object_Declaration)
3997 and then Exception_Junk (Last_Stm))
3998 or else Nkind (Last_Stm) in N_Push_xxx_Label
3999 or else Nkind (Last_Stm) in N_Pop_xxx_Label
4004 -- Here we have the "real" last statement
4006 Kind := Nkind (Last_Stm);
4008 -- Transfer of control, OK. Note that in the No_Return procedure
4009 -- case, we already diagnosed any explicit return statements, so
4010 -- we can treat them as OK in this context.
4012 if Is_Transfer (Last_Stm) then
4015 -- Check cases of explicit non-indirect procedure calls
4017 elsif Kind = N_Procedure_Call_Statement
4018 and then Is_Entity_Name (Name (Last_Stm))
4020 -- Check call to Raise_Exception procedure which is treated
4021 -- specially, as is a call to Reraise_Occurrence.
4023 -- We suppress the warning in these cases since it is likely that
4024 -- the programmer really does not expect to deal with the case
4025 -- of Null_Occurrence, and thus would find a warning about a
4026 -- missing return curious, and raising Program_Error does not
4027 -- seem such a bad behavior if this does occur.
4029 -- Note that in the Ada 2005 case for Raise_Exception, the actual
4030 -- behavior will be to raise Constraint_Error (see AI-329).
4032 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
4034 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
4036 Raise_Exception_Call := True;
4038 -- For Raise_Exception call, test first argument, if it is
4039 -- an attribute reference for a 'Identity call, then we know
4040 -- that the call cannot possibly return.
4043 Arg : constant Node_Id :=
4044 Original_Node (First_Actual (Last_Stm));
4046 if Nkind (Arg) = N_Attribute_Reference
4047 and then Attribute_Name (Arg) = Name_Identity
4054 -- If statement, need to look inside if there is an else and check
4055 -- each constituent statement sequence for proper termination.
4057 elsif Kind = N_If_Statement
4058 and then Present (Else_Statements (Last_Stm))
4060 Check_Statement_Sequence (Then_Statements (Last_Stm));
4061 Check_Statement_Sequence (Else_Statements (Last_Stm));
4063 if Present (Elsif_Parts (Last_Stm)) then
4065 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
4068 while Present (Elsif_Part) loop
4069 Check_Statement_Sequence (Then_Statements (Elsif_Part));
4077 -- Case statement, check each case for proper termination
4079 elsif Kind = N_Case_Statement then
4084 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
4085 while Present (Case_Alt) loop
4086 Check_Statement_Sequence (Statements (Case_Alt));
4087 Next_Non_Pragma (Case_Alt);
4093 -- Block statement, check its handled sequence of statements
4095 elsif Kind = N_Block_Statement then
4101 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
4110 -- Loop statement. If there is an iteration scheme, we can definitely
4111 -- fall out of the loop. Similarly if there is an exit statement, we
4112 -- can fall out. In either case we need a following return.
4114 elsif Kind = N_Loop_Statement then
4115 if Present (Iteration_Scheme (Last_Stm))
4116 or else Has_Exit (Entity (Identifier (Last_Stm)))
4120 -- A loop with no exit statement or iteration scheme if either
4121 -- an inifite loop, or it has some other exit (raise/return).
4122 -- In either case, no warning is required.
4128 -- Timed entry call, check entry call and delay alternatives
4130 -- Note: in expanded code, the timed entry call has been converted
4131 -- to a set of expanded statements on which the check will work
4132 -- correctly in any case.
4134 elsif Kind = N_Timed_Entry_Call then
4136 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4137 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
4140 -- If statement sequence of entry call alternative is missing,
4141 -- then we can definitely fall through, and we post the error
4142 -- message on the entry call alternative itself.
4144 if No (Statements (ECA)) then
4147 -- If statement sequence of delay alternative is missing, then
4148 -- we can definitely fall through, and we post the error
4149 -- message on the delay alternative itself.
4151 -- Note: if both ECA and DCA are missing the return, then we
4152 -- post only one message, should be enough to fix the bugs.
4153 -- If not we will get a message next time on the DCA when the
4156 elsif No (Statements (DCA)) then
4159 -- Else check both statement sequences
4162 Check_Statement_Sequence (Statements (ECA));
4163 Check_Statement_Sequence (Statements (DCA));
4168 -- Conditional entry call, check entry call and else part
4170 -- Note: in expanded code, the conditional entry call has been
4171 -- converted to a set of expanded statements on which the check
4172 -- will work correctly in any case.
4174 elsif Kind = N_Conditional_Entry_Call then
4176 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
4179 -- If statement sequence of entry call alternative is missing,
4180 -- then we can definitely fall through, and we post the error
4181 -- message on the entry call alternative itself.
4183 if No (Statements (ECA)) then
4186 -- Else check statement sequence and else part
4189 Check_Statement_Sequence (Statements (ECA));
4190 Check_Statement_Sequence (Else_Statements (Last_Stm));
4196 -- If we fall through, issue appropriate message
4199 if not Raise_Exception_Call then
4201 ("?RETURN statement missing following this statement!",
4204 ("\?Program_Error may be raised at run time!",
4208 -- Note: we set Err even though we have not issued a warning
4209 -- because we still have a case of a missing return. This is
4210 -- an extremely marginal case, probably will never be noticed
4211 -- but we might as well get it right.
4215 -- Otherwise we have the case of a procedure marked No_Return
4219 ("?implied return after this statement will raise Program_Error",
4222 ("?procedure & is marked as No_Return",
4226 RE : constant Node_Id :=
4227 Make_Raise_Program_Error (Sloc (Last_Stm),
4228 Reason => PE_Implicit_Return);
4230 Insert_After (Last_Stm, RE);
4234 end Check_Statement_Sequence;
4236 -- Start of processing for Check_Returns
4240 Check_Statement_Sequence (Statements (HSS));
4242 if Present (Exception_Handlers (HSS)) then
4243 Handler := First_Non_Pragma (Exception_Handlers (HSS));
4244 while Present (Handler) loop
4245 Check_Statement_Sequence (Statements (Handler));
4246 Next_Non_Pragma (Handler);
4251 ----------------------------
4252 -- Check_Subprogram_Order --
4253 ----------------------------
4255 procedure Check_Subprogram_Order (N : Node_Id) is
4257 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
4258 -- This is used to check if S1 > S2 in the sense required by this
4259 -- test, for example nameab < namec, but name2 < name10.
4261 -----------------------------
4262 -- Subprogram_Name_Greater --
4263 -----------------------------
4265 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
4270 -- Remove trailing numeric parts
4273 while S1 (L1) in '0' .. '9' loop
4278 while S2 (L2) in '0' .. '9' loop
4282 -- If non-numeric parts non-equal, that's decisive
4284 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
4287 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
4290 -- If non-numeric parts equal, compare suffixed numeric parts. Note
4291 -- that a missing suffix is treated as numeric zero in this test.
4295 while L1 < S1'Last loop
4297 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
4301 while L2 < S2'Last loop
4303 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
4308 end Subprogram_Name_Greater;
4310 -- Start of processing for Check_Subprogram_Order
4313 -- Check body in alpha order if this is option
4316 and then Style_Check_Order_Subprograms
4317 and then Nkind (N) = N_Subprogram_Body
4318 and then Comes_From_Source (N)
4319 and then In_Extended_Main_Source_Unit (N)
4323 renames Scope_Stack.Table
4324 (Scope_Stack.Last).Last_Subprogram_Name;
4326 Body_Id : constant Entity_Id :=
4327 Defining_Entity (Specification (N));
4330 Get_Decoded_Name_String (Chars (Body_Id));
4333 if Subprogram_Name_Greater
4334 (LSN.all, Name_Buffer (1 .. Name_Len))
4336 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
4342 LSN := new String'(Name_Buffer (1 .. Name_Len));
4345 end Check_Subprogram_Order;
4347 ------------------------------
4348 -- Check_Subtype_Conformant --
4349 ------------------------------
4351 procedure Check_Subtype_Conformant
4352 (New_Id : Entity_Id;
4354 Err_Loc : Node_Id := Empty)
4359 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc);
4360 end Check_Subtype_Conformant;
4362 ---------------------------
4363 -- Check_Type_Conformant --
4364 ---------------------------
4366 procedure Check_Type_Conformant
4367 (New_Id : Entity_Id;
4369 Err_Loc : Node_Id := Empty)
4374 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
4375 end Check_Type_Conformant;
4377 ----------------------
4378 -- Conforming_Types --
4379 ----------------------
4381 function Conforming_Types
4384 Ctype : Conformance_Type;
4385 Get_Inst : Boolean := False) return Boolean
4387 Type_1 : Entity_Id := T1;
4388 Type_2 : Entity_Id := T2;
4389 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
4391 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
4392 -- If neither T1 nor T2 are generic actual types, or if they are in
4393 -- different scopes (e.g. parent and child instances), then verify that
4394 -- the base types are equal. Otherwise T1 and T2 must be on the same
4395 -- subtype chain. The whole purpose of this procedure is to prevent
4396 -- spurious ambiguities in an instantiation that may arise if two
4397 -- distinct generic types are instantiated with the same actual.
4399 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
4400 -- An access parameter can designate an incomplete type. If the
4401 -- incomplete type is the limited view of a type from a limited_
4402 -- with_clause, check whether the non-limited view is available. If
4403 -- it is a (non-limited) incomplete type, get the full view.
4405 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
4406 -- Returns True if and only if either T1 denotes a limited view of T2
4407 -- or T2 denotes a limited view of T1. This can arise when the limited
4408 -- with view of a type is used in a subprogram declaration and the
4409 -- subprogram body is in the scope of a regular with clause for the
4410 -- same unit. In such a case, the two type entities can be considered
4411 -- identical for purposes of conformance checking.
4413 ----------------------
4414 -- Base_Types_Match --
4415 ----------------------
4417 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
4422 elsif Base_Type (T1) = Base_Type (T2) then
4424 -- The following is too permissive. A more precise test should
4425 -- check that the generic actual is an ancestor subtype of the
4428 return not Is_Generic_Actual_Type (T1)
4429 or else not Is_Generic_Actual_Type (T2)
4430 or else Scope (T1) /= Scope (T2);
4435 end Base_Types_Match;
4437 --------------------------
4438 -- Find_Designated_Type --
4439 --------------------------
4441 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
4445 Desig := Directly_Designated_Type (T);
4447 if Ekind (Desig) = E_Incomplete_Type then
4449 -- If regular incomplete type, get full view if available
4451 if Present (Full_View (Desig)) then
4452 Desig := Full_View (Desig);
4454 -- If limited view of a type, get non-limited view if available,
4455 -- and check again for a regular incomplete type.
4457 elsif Present (Non_Limited_View (Desig)) then
4458 Desig := Get_Full_View (Non_Limited_View (Desig));
4463 end Find_Designated_Type;
4465 -------------------------------
4466 -- Matches_Limited_With_View --
4467 -------------------------------
4469 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
4471 -- In some cases a type imported through a limited_with clause, and
4472 -- its nonlimited view are both visible, for example in an anonymous
4473 -- access-to-class-wide type in a formal. Both entities designate the
4476 if From_With_Type (T1)
4477 and then T2 = Available_View (T1)
4481 elsif From_With_Type (T2)
4482 and then T1 = Available_View (T2)
4489 end Matches_Limited_With_View;
4491 -- Start of processing for Conforming_Types
4494 -- The context is an instance association for a formal
4495 -- access-to-subprogram type; the formal parameter types require
4496 -- mapping because they may denote other formal parameters of the
4500 Type_1 := Get_Instance_Of (T1);
4501 Type_2 := Get_Instance_Of (T2);
4504 -- If one of the types is a view of the other introduced by a limited
4505 -- with clause, treat these as conforming for all purposes.
4507 if Matches_Limited_With_View (T1, T2) then
4510 elsif Base_Types_Match (Type_1, Type_2) then
4511 return Ctype <= Mode_Conformant
4512 or else Subtypes_Statically_Match (Type_1, Type_2);
4514 elsif Is_Incomplete_Or_Private_Type (Type_1)
4515 and then Present (Full_View (Type_1))
4516 and then Base_Types_Match (Full_View (Type_1), Type_2)
4518 return Ctype <= Mode_Conformant
4519 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
4521 elsif Ekind (Type_2) = E_Incomplete_Type
4522 and then Present (Full_View (Type_2))
4523 and then Base_Types_Match (Type_1, Full_View (Type_2))
4525 return Ctype <= Mode_Conformant
4526 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4528 elsif Is_Private_Type (Type_2)
4529 and then In_Instance
4530 and then Present (Full_View (Type_2))
4531 and then Base_Types_Match (Type_1, Full_View (Type_2))
4533 return Ctype <= Mode_Conformant
4534 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
4537 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
4538 -- treated recursively because they carry a signature.
4540 Are_Anonymous_Access_To_Subprogram_Types :=
4541 Ekind (Type_1) = Ekind (Type_2)
4543 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
4545 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
4547 -- Test anonymous access type case. For this case, static subtype
4548 -- matching is required for mode conformance (RM 6.3.1(15)). We check
4549 -- the base types because we may have built internal subtype entities
4550 -- to handle null-excluding types (see Process_Formals).
4552 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
4554 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
4555 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
4558 Desig_1 : Entity_Id;
4559 Desig_2 : Entity_Id;
4562 -- In Ada2005, access constant indicators must match for
4563 -- subtype conformance.
4565 if Ada_Version >= Ada_05
4566 and then Ctype >= Subtype_Conformant
4568 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
4573 Desig_1 := Find_Designated_Type (Type_1);
4575 Desig_2 := Find_Designated_Type (Type_2);
4577 -- If the context is an instance association for a formal
4578 -- access-to-subprogram type; formal access parameter designated
4579 -- types require mapping because they may denote other formal
4580 -- parameters of the generic unit.
4583 Desig_1 := Get_Instance_Of (Desig_1);
4584 Desig_2 := Get_Instance_Of (Desig_2);
4587 -- It is possible for a Class_Wide_Type to be introduced for an
4588 -- incomplete type, in which case there is a separate class_ wide
4589 -- type for the full view. The types conform if their Etypes
4590 -- conform, i.e. one may be the full view of the other. This can
4591 -- only happen in the context of an access parameter, other uses
4592 -- of an incomplete Class_Wide_Type are illegal.
4594 if Is_Class_Wide_Type (Desig_1)
4595 and then Is_Class_Wide_Type (Desig_2)
4599 (Etype (Base_Type (Desig_1)),
4600 Etype (Base_Type (Desig_2)), Ctype);
4602 elsif Are_Anonymous_Access_To_Subprogram_Types then
4603 if Ada_Version < Ada_05 then
4604 return Ctype = Type_Conformant
4606 Subtypes_Statically_Match (Desig_1, Desig_2);
4608 -- We must check the conformance of the signatures themselves
4612 Conformant : Boolean;
4615 (Desig_1, Desig_2, Ctype, False, Conformant);
4621 return Base_Type (Desig_1) = Base_Type (Desig_2)
4622 and then (Ctype = Type_Conformant
4624 Subtypes_Statically_Match (Desig_1, Desig_2));
4628 -- Otherwise definitely no match
4631 if ((Ekind (Type_1) = E_Anonymous_Access_Type
4632 and then Is_Access_Type (Type_2))
4633 or else (Ekind (Type_2) = E_Anonymous_Access_Type
4634 and then Is_Access_Type (Type_1)))
4637 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
4639 May_Hide_Profile := True;
4644 end Conforming_Types;
4646 --------------------------
4647 -- Create_Extra_Formals --
4648 --------------------------
4650 procedure Create_Extra_Formals (E : Entity_Id) is
4652 First_Extra : Entity_Id := Empty;
4653 Last_Extra : Entity_Id;
4654 Formal_Type : Entity_Id;
4655 P_Formal : Entity_Id := Empty;
4657 function Add_Extra_Formal
4658 (Assoc_Entity : Entity_Id;
4661 Suffix : String) return Entity_Id;
4662 -- Add an extra formal to the current list of formals and extra formals.
4663 -- The extra formal is added to the end of the list of extra formals,
4664 -- and also returned as the result. These formals are always of mode IN.
4665 -- The new formal has the type Typ, is declared in Scope, and its name
4666 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
4668 ----------------------
4669 -- Add_Extra_Formal --
4670 ----------------------
4672 function Add_Extra_Formal
4673 (Assoc_Entity : Entity_Id;
4676 Suffix : String) return Entity_Id
4678 EF : constant Entity_Id :=
4679 Make_Defining_Identifier (Sloc (Assoc_Entity),
4680 Chars => New_External_Name (Chars (Assoc_Entity),
4684 -- A little optimization. Never generate an extra formal for the
4685 -- _init operand of an initialization procedure, since it could
4688 if Chars (Formal) = Name_uInit then
4692 Set_Ekind (EF, E_In_Parameter);
4693 Set_Actual_Subtype (EF, Typ);
4694 Set_Etype (EF, Typ);
4695 Set_Scope (EF, Scope);
4696 Set_Mechanism (EF, Default_Mechanism);
4697 Set_Formal_Validity (EF);
4699 if No (First_Extra) then
4701 Set_Extra_Formals (Scope, First_Extra);
4704 if Present (Last_Extra) then
4705 Set_Extra_Formal (Last_Extra, EF);
4711 end Add_Extra_Formal;
4713 -- Start of processing for Create_Extra_Formals
4716 -- We never generate extra formals if expansion is not active
4717 -- because we don't need them unless we are generating code.
4719 if not Expander_Active then
4723 -- If this is a derived subprogram then the subtypes of the parent
4724 -- subprogram's formal parameters will be used to to determine the need
4725 -- for extra formals.
4727 if Is_Overloadable (E) and then Present (Alias (E)) then
4728 P_Formal := First_Formal (Alias (E));
4731 Last_Extra := Empty;
4732 Formal := First_Formal (E);
4733 while Present (Formal) loop
4734 Last_Extra := Formal;
4735 Next_Formal (Formal);
4738 -- If Extra_formals were already created, don't do it again. This
4739 -- situation may arise for subprogram types created as part of
4740 -- dispatching calls (see Expand_Dispatching_Call)
4742 if Present (Last_Extra) and then
4743 Present (Extra_Formal (Last_Extra))
4748 -- If the subprogram is a predefined dispatching subprogram then don't
4749 -- generate any extra constrained or accessibility level formals. In
4750 -- general we suppress these for internal subprograms (by not calling
4751 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
4752 -- generated stream attributes do get passed through because extra
4753 -- build-in-place formals are needed in some cases (limited 'Input).
4755 if Is_Predefined_Dispatching_Operation (E) then
4756 goto Test_For_BIP_Extras;
4759 Formal := First_Formal (E);
4760 while Present (Formal) loop
4762 -- Create extra formal for supporting the attribute 'Constrained.
4763 -- The case of a private type view without discriminants also
4764 -- requires the extra formal if the underlying type has defaulted
4767 if Ekind (Formal) /= E_In_Parameter then
4768 if Present (P_Formal) then
4769 Formal_Type := Etype (P_Formal);
4771 Formal_Type := Etype (Formal);
4774 -- Do not produce extra formals for Unchecked_Union parameters.
4775 -- Jump directly to the end of the loop.
4777 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
4778 goto Skip_Extra_Formal_Generation;
4781 if not Has_Discriminants (Formal_Type)
4782 and then Ekind (Formal_Type) in Private_Kind
4783 and then Present (Underlying_Type (Formal_Type))
4785 Formal_Type := Underlying_Type (Formal_Type);
4788 if Has_Discriminants (Formal_Type)
4789 and then not Is_Constrained (Formal_Type)
4790 and then not Is_Indefinite_Subtype (Formal_Type)
4792 Set_Extra_Constrained
4793 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "F"));
4797 -- Create extra formal for supporting accessibility checking. This
4798 -- is done for both anonymous access formals and formals of named
4799 -- access types that are marked as controlling formals. The latter
4800 -- case can occur when Expand_Dispatching_Call creates a subprogram
4801 -- type and substitutes the types of access-to-class-wide actuals
4802 -- for the anonymous access-to-specific-type of controlling formals.
4803 -- Base_Type is applied because in cases where there is a null
4804 -- exclusion the formal may have an access subtype.
4806 -- This is suppressed if we specifically suppress accessibility
4807 -- checks at the package level for either the subprogram, or the
4808 -- package in which it resides. However, we do not suppress it
4809 -- simply if the scope has accessibility checks suppressed, since
4810 -- this could cause trouble when clients are compiled with a
4811 -- different suppression setting. The explicit checks at the
4812 -- package level are safe from this point of view.
4814 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
4815 or else (Is_Controlling_Formal (Formal)
4816 and then Is_Access_Type (Base_Type (Etype (Formal)))))
4818 (Explicit_Suppress (E, Accessibility_Check)
4820 Explicit_Suppress (Scope (E), Accessibility_Check))
4823 or else Present (Extra_Accessibility (P_Formal)))
4825 -- Temporary kludge: for now we avoid creating the extra formal
4826 -- for access parameters of protected operations because of
4827 -- problem with the case of internal protected calls. ???
4829 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
4830 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
4832 Set_Extra_Accessibility
4833 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "F"));
4837 -- This label is required when skipping extra formal generation for
4838 -- Unchecked_Union parameters.
4840 <<Skip_Extra_Formal_Generation>>
4842 if Present (P_Formal) then
4843 Next_Formal (P_Formal);
4846 Next_Formal (Formal);
4849 <<Test_For_BIP_Extras>>
4851 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
4852 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
4854 if Ada_Version >= Ada_05 and then Is_Build_In_Place_Function (E) then
4856 Result_Subt : constant Entity_Id := Etype (E);
4858 Discard : Entity_Id;
4859 pragma Warnings (Off, Discard);
4862 -- In the case of functions with unconstrained result subtypes,
4863 -- add a 3-state formal indicating whether the return object is
4864 -- allocated by the caller (0), or should be allocated by the
4865 -- callee on the secondary stack (1) or in the global heap (2).
4866 -- For the moment we just use Natural for the type of this formal.
4867 -- Note that this formal isn't usually needed in the case where
4868 -- the result subtype is constrained, but it is needed when the
4869 -- function has a tagged result, because generally such functions
4870 -- can be called in a dispatching context and such calls must be
4871 -- handled like calls to a class-wide function.
4873 if not Is_Constrained (Result_Subt)
4874 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
4878 (E, Standard_Natural,
4879 E, BIP_Formal_Suffix (BIP_Alloc_Form));
4882 -- In the case of functions whose result type has controlled
4883 -- parts, we have an extra formal of type
4884 -- System.Finalization_Implementation.Finalizable_Ptr_Ptr. That
4885 -- is, we are passing a pointer to a finalization list (which is
4886 -- itself a pointer). This extra formal is then passed along to
4887 -- Move_Final_List in case of successful completion of a return
4888 -- statement. We cannot pass an 'in out' parameter, because we
4889 -- need to update the finalization list during an abort-deferred
4890 -- region, rather than using copy-back after the function
4891 -- returns. This is true even if we are able to get away with
4892 -- having 'in out' parameters, which are normally illegal for
4893 -- functions. This formal is also needed when the function has
4894 -- a tagged result, because generally such functions can be called
4895 -- in a dispatching context and such calls must be handled like
4896 -- calls to class-wide functions.
4898 if Controlled_Type (Result_Subt)
4899 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
4903 (E, RTE (RE_Finalizable_Ptr_Ptr),
4904 E, BIP_Formal_Suffix (BIP_Final_List));
4907 -- If the result type contains tasks, we have two extra formals:
4908 -- the master of the tasks to be created, and the caller's
4909 -- activation chain.
4911 if Has_Task (Result_Subt) then
4914 (E, RTE (RE_Master_Id),
4915 E, BIP_Formal_Suffix (BIP_Master));
4918 (E, RTE (RE_Activation_Chain_Access),
4919 E, BIP_Formal_Suffix (BIP_Activation_Chain));
4922 -- All build-in-place functions get an extra formal that will be
4923 -- passed the address of the return object within the caller.
4926 Formal_Type : constant Entity_Id :=
4928 (E_Anonymous_Access_Type, E,
4929 Scope_Id => Scope (E));
4931 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
4932 Set_Etype (Formal_Type, Formal_Type);
4933 Init_Size_Align (Formal_Type);
4934 Set_Depends_On_Private
4935 (Formal_Type, Has_Private_Component (Formal_Type));
4936 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
4937 Set_Is_Access_Constant (Formal_Type, False);
4939 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
4940 -- the designated type comes from the limited view (for
4941 -- back-end purposes).
4943 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
4945 Layout_Type (Formal_Type);
4949 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
4953 end Create_Extra_Formals;
4955 -----------------------------
4956 -- Enter_Overloaded_Entity --
4957 -----------------------------
4959 procedure Enter_Overloaded_Entity (S : Entity_Id) is
4960 E : Entity_Id := Current_Entity_In_Scope (S);
4961 C_E : Entity_Id := Current_Entity (S);
4965 Set_Has_Homonym (E);
4966 Set_Has_Homonym (S);
4969 Set_Is_Immediately_Visible (S);
4970 Set_Scope (S, Current_Scope);
4972 -- Chain new entity if front of homonym in current scope, so that
4973 -- homonyms are contiguous.
4978 while Homonym (C_E) /= E loop
4979 C_E := Homonym (C_E);
4982 Set_Homonym (C_E, S);
4986 Set_Current_Entity (S);
4991 Append_Entity (S, Current_Scope);
4992 Set_Public_Status (S);
4994 if Debug_Flag_E then
4995 Write_Str ("New overloaded entity chain: ");
4996 Write_Name (Chars (S));
4999 while Present (E) loop
5000 Write_Str (" "); Write_Int (Int (E));
5007 -- Generate warning for hiding
5010 and then Comes_From_Source (S)
5011 and then In_Extended_Main_Source_Unit (S)
5018 -- Warn unless genuine overloading
5020 if (not Is_Overloadable (E) or else Subtype_Conformant (E, S))
5021 and then (Is_Immediately_Visible (E)
5023 Is_Potentially_Use_Visible (S))
5025 Error_Msg_Sloc := Sloc (E);
5026 Error_Msg_N ("declaration of & hides one#?", S);
5030 end Enter_Overloaded_Entity;
5032 -----------------------------
5033 -- Find_Corresponding_Spec --
5034 -----------------------------
5036 function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is
5037 Spec : constant Node_Id := Specification (N);
5038 Designator : constant Entity_Id := Defining_Entity (Spec);
5043 E := Current_Entity (Designator);
5044 while Present (E) loop
5046 -- We are looking for a matching spec. It must have the same scope,
5047 -- and the same name, and either be type conformant, or be the case
5048 -- of a library procedure spec and its body (which belong to one
5049 -- another regardless of whether they are type conformant or not).
5051 if Scope (E) = Current_Scope then
5052 if Current_Scope = Standard_Standard
5053 or else (Ekind (E) = Ekind (Designator)
5054 and then Type_Conformant (E, Designator))
5056 -- Within an instantiation, we know that spec and body are
5057 -- subtype conformant, because they were subtype conformant
5058 -- in the generic. We choose the subtype-conformant entity
5059 -- here as well, to resolve spurious ambiguities in the
5060 -- instance that were not present in the generic (i.e. when
5061 -- two different types are given the same actual). If we are
5062 -- looking for a spec to match a body, full conformance is
5066 Set_Convention (Designator, Convention (E));
5068 if Nkind (N) = N_Subprogram_Body
5069 and then Present (Homonym (E))
5070 and then not Fully_Conformant (E, Designator)
5074 elsif not Subtype_Conformant (E, Designator) then
5079 if not Has_Completion (E) then
5081 if Nkind (N) /= N_Subprogram_Body_Stub then
5082 Set_Corresponding_Spec (N, E);
5085 Set_Has_Completion (E);
5088 elsif Nkind (Parent (N)) = N_Subunit then
5090 -- If this is the proper body of a subunit, the completion
5091 -- flag is set when analyzing the stub.
5095 -- If body already exists, this is an error unless the
5096 -- previous declaration is the implicit declaration of
5097 -- a derived subprogram, or this is a spurious overloading
5100 elsif No (Alias (E))
5101 and then not Is_Intrinsic_Subprogram (E)
5102 and then not In_Instance
5104 Error_Msg_Sloc := Sloc (E);
5105 if Is_Imported (E) then
5107 ("body not allowed for imported subprogram & declared#",
5110 Error_Msg_NE ("duplicate body for & declared#", N, E);
5114 elsif Is_Child_Unit (E)
5116 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
5118 Nkind (Parent (Unit_Declaration_Node (Designator))) =
5121 -- Child units cannot be overloaded, so a conformance mismatch
5122 -- between body and a previous spec is an error.
5125 ("body of child unit does not match previous declaration", N);
5133 -- On exit, we know that no previous declaration of subprogram exists
5136 end Find_Corresponding_Spec;
5138 ----------------------
5139 -- Fully_Conformant --
5140 ----------------------
5142 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5145 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
5147 end Fully_Conformant;
5149 ----------------------------------
5150 -- Fully_Conformant_Expressions --
5151 ----------------------------------
5153 function Fully_Conformant_Expressions
5154 (Given_E1 : Node_Id;
5155 Given_E2 : Node_Id) return Boolean
5157 E1 : constant Node_Id := Original_Node (Given_E1);
5158 E2 : constant Node_Id := Original_Node (Given_E2);
5159 -- We always test conformance on original nodes, since it is possible
5160 -- for analysis and/or expansion to make things look as though they
5161 -- conform when they do not, e.g. by converting 1+2 into 3.
5163 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
5164 renames Fully_Conformant_Expressions;
5166 function FCL (L1, L2 : List_Id) return Boolean;
5167 -- Compare elements of two lists for conformance. Elements have to
5168 -- be conformant, and actuals inserted as default parameters do not
5169 -- match explicit actuals with the same value.
5171 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
5172 -- Compare an operator node with a function call
5178 function FCL (L1, L2 : List_Id) return Boolean is
5182 if L1 = No_List then
5188 if L2 = No_List then
5194 -- Compare two lists, skipping rewrite insertions (we want to
5195 -- compare the original trees, not the expanded versions!)
5198 if Is_Rewrite_Insertion (N1) then
5200 elsif Is_Rewrite_Insertion (N2) then
5206 elsif not FCE (N1, N2) then
5219 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
5220 Actuals : constant List_Id := Parameter_Associations (Call_Node);
5225 or else Entity (Op_Node) /= Entity (Name (Call_Node))
5230 Act := First (Actuals);
5232 if Nkind (Op_Node) in N_Binary_Op then
5234 if not FCE (Left_Opnd (Op_Node), Act) then
5241 return Present (Act)
5242 and then FCE (Right_Opnd (Op_Node), Act)
5243 and then No (Next (Act));
5247 -- Start of processing for Fully_Conformant_Expressions
5250 -- Non-conformant if paren count does not match. Note: if some idiot
5251 -- complains that we don't do this right for more than 3 levels of
5252 -- parentheses, they will be treated with the respect they deserve!
5254 if Paren_Count (E1) /= Paren_Count (E2) then
5257 -- If same entities are referenced, then they are conformant even if
5258 -- they have different forms (RM 8.3.1(19-20)).
5260 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
5261 if Present (Entity (E1)) then
5262 return Entity (E1) = Entity (E2)
5263 or else (Chars (Entity (E1)) = Chars (Entity (E2))
5264 and then Ekind (Entity (E1)) = E_Discriminant
5265 and then Ekind (Entity (E2)) = E_In_Parameter);
5267 elsif Nkind (E1) = N_Expanded_Name
5268 and then Nkind (E2) = N_Expanded_Name
5269 and then Nkind (Selector_Name (E1)) = N_Character_Literal
5270 and then Nkind (Selector_Name (E2)) = N_Character_Literal
5272 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
5275 -- Identifiers in component associations don't always have
5276 -- entities, but their names must conform.
5278 return Nkind (E1) = N_Identifier
5279 and then Nkind (E2) = N_Identifier
5280 and then Chars (E1) = Chars (E2);
5283 elsif Nkind (E1) = N_Character_Literal
5284 and then Nkind (E2) = N_Expanded_Name
5286 return Nkind (Selector_Name (E2)) = N_Character_Literal
5287 and then Chars (E1) = Chars (Selector_Name (E2));
5289 elsif Nkind (E2) = N_Character_Literal
5290 and then Nkind (E1) = N_Expanded_Name
5292 return Nkind (Selector_Name (E1)) = N_Character_Literal
5293 and then Chars (E2) = Chars (Selector_Name (E1));
5295 elsif Nkind (E1) in N_Op
5296 and then Nkind (E2) = N_Function_Call
5298 return FCO (E1, E2);
5300 elsif Nkind (E2) in N_Op
5301 and then Nkind (E1) = N_Function_Call
5303 return FCO (E2, E1);
5305 -- Otherwise we must have the same syntactic entity
5307 elsif Nkind (E1) /= Nkind (E2) then
5310 -- At this point, we specialize by node type
5317 FCL (Expressions (E1), Expressions (E2))
5318 and then FCL (Component_Associations (E1),
5319 Component_Associations (E2));
5322 if Nkind (Expression (E1)) = N_Qualified_Expression
5324 Nkind (Expression (E2)) = N_Qualified_Expression
5326 return FCE (Expression (E1), Expression (E2));
5328 -- Check that the subtype marks and any constraints
5333 Indic1 : constant Node_Id := Expression (E1);
5334 Indic2 : constant Node_Id := Expression (E2);
5339 if Nkind (Indic1) /= N_Subtype_Indication then
5341 Nkind (Indic2) /= N_Subtype_Indication
5342 and then Entity (Indic1) = Entity (Indic2);
5344 elsif Nkind (Indic2) /= N_Subtype_Indication then
5346 Nkind (Indic1) /= N_Subtype_Indication
5347 and then Entity (Indic1) = Entity (Indic2);
5350 if Entity (Subtype_Mark (Indic1)) /=
5351 Entity (Subtype_Mark (Indic2))
5356 Elt1 := First (Constraints (Constraint (Indic1)));
5357 Elt2 := First (Constraints (Constraint (Indic2)));
5359 while Present (Elt1) and then Present (Elt2) loop
5360 if not FCE (Elt1, Elt2) then
5373 when N_Attribute_Reference =>
5375 Attribute_Name (E1) = Attribute_Name (E2)
5376 and then FCL (Expressions (E1), Expressions (E2));
5380 Entity (E1) = Entity (E2)
5381 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
5382 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5384 when N_And_Then | N_Or_Else | N_Membership_Test =>
5386 FCE (Left_Opnd (E1), Left_Opnd (E2))
5388 FCE (Right_Opnd (E1), Right_Opnd (E2));
5390 when N_Character_Literal =>
5392 Char_Literal_Value (E1) = Char_Literal_Value (E2);
5394 when N_Component_Association =>
5396 FCL (Choices (E1), Choices (E2))
5397 and then FCE (Expression (E1), Expression (E2));
5399 when N_Conditional_Expression =>
5401 FCL (Expressions (E1), Expressions (E2));
5403 when N_Explicit_Dereference =>
5405 FCE (Prefix (E1), Prefix (E2));
5407 when N_Extension_Aggregate =>
5409 FCL (Expressions (E1), Expressions (E2))
5410 and then Null_Record_Present (E1) =
5411 Null_Record_Present (E2)
5412 and then FCL (Component_Associations (E1),
5413 Component_Associations (E2));
5415 when N_Function_Call =>
5417 FCE (Name (E1), Name (E2))
5418 and then FCL (Parameter_Associations (E1),
5419 Parameter_Associations (E2));
5421 when N_Indexed_Component =>
5423 FCE (Prefix (E1), Prefix (E2))
5424 and then FCL (Expressions (E1), Expressions (E2));
5426 when N_Integer_Literal =>
5427 return (Intval (E1) = Intval (E2));
5432 when N_Operator_Symbol =>
5434 Chars (E1) = Chars (E2);
5436 when N_Others_Choice =>
5439 when N_Parameter_Association =>
5441 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
5442 and then FCE (Explicit_Actual_Parameter (E1),
5443 Explicit_Actual_Parameter (E2));
5445 when N_Qualified_Expression =>
5447 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5448 and then FCE (Expression (E1), Expression (E2));
5452 FCE (Low_Bound (E1), Low_Bound (E2))
5453 and then FCE (High_Bound (E1), High_Bound (E2));
5455 when N_Real_Literal =>
5456 return (Realval (E1) = Realval (E2));
5458 when N_Selected_Component =>
5460 FCE (Prefix (E1), Prefix (E2))
5461 and then FCE (Selector_Name (E1), Selector_Name (E2));
5465 FCE (Prefix (E1), Prefix (E2))
5466 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
5468 when N_String_Literal =>
5470 S1 : constant String_Id := Strval (E1);
5471 S2 : constant String_Id := Strval (E2);
5472 L1 : constant Nat := String_Length (S1);
5473 L2 : constant Nat := String_Length (S2);
5480 for J in 1 .. L1 loop
5481 if Get_String_Char (S1, J) /=
5482 Get_String_Char (S2, J)
5492 when N_Type_Conversion =>
5494 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5495 and then FCE (Expression (E1), Expression (E2));
5499 Entity (E1) = Entity (E2)
5500 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
5502 when N_Unchecked_Type_Conversion =>
5504 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
5505 and then FCE (Expression (E1), Expression (E2));
5507 -- All other node types cannot appear in this context. Strictly
5508 -- we should raise a fatal internal error. Instead we just ignore
5509 -- the nodes. This means that if anyone makes a mistake in the
5510 -- expander and mucks an expression tree irretrievably, the
5511 -- result will be a failure to detect a (probably very obscure)
5512 -- case of non-conformance, which is better than bombing on some
5513 -- case where two expressions do in fact conform.
5520 end Fully_Conformant_Expressions;
5522 ----------------------------------------
5523 -- Fully_Conformant_Discrete_Subtypes --
5524 ----------------------------------------
5526 function Fully_Conformant_Discrete_Subtypes
5527 (Given_S1 : Node_Id;
5528 Given_S2 : Node_Id) return Boolean
5530 S1 : constant Node_Id := Original_Node (Given_S1);
5531 S2 : constant Node_Id := Original_Node (Given_S2);
5533 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
5534 -- Special-case for a bound given by a discriminant, which in the body
5535 -- is replaced with the discriminal of the enclosing type.
5537 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
5538 -- Check both bounds
5540 -----------------------
5541 -- Conforming_Bounds --
5542 -----------------------
5544 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
5546 if Is_Entity_Name (B1)
5547 and then Is_Entity_Name (B2)
5548 and then Ekind (Entity (B1)) = E_Discriminant
5550 return Chars (B1) = Chars (B2);
5553 return Fully_Conformant_Expressions (B1, B2);
5555 end Conforming_Bounds;
5557 -----------------------
5558 -- Conforming_Ranges --
5559 -----------------------
5561 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
5564 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
5566 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
5567 end Conforming_Ranges;
5569 -- Start of processing for Fully_Conformant_Discrete_Subtypes
5572 if Nkind (S1) /= Nkind (S2) then
5575 elsif Is_Entity_Name (S1) then
5576 return Entity (S1) = Entity (S2);
5578 elsif Nkind (S1) = N_Range then
5579 return Conforming_Ranges (S1, S2);
5581 elsif Nkind (S1) = N_Subtype_Indication then
5583 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
5586 (Range_Expression (Constraint (S1)),
5587 Range_Expression (Constraint (S2)));
5591 end Fully_Conformant_Discrete_Subtypes;
5593 --------------------
5594 -- Install_Entity --
5595 --------------------
5597 procedure Install_Entity (E : Entity_Id) is
5598 Prev : constant Entity_Id := Current_Entity (E);
5600 Set_Is_Immediately_Visible (E);
5601 Set_Current_Entity (E);
5602 Set_Homonym (E, Prev);
5605 ---------------------
5606 -- Install_Formals --
5607 ---------------------
5609 procedure Install_Formals (Id : Entity_Id) is
5612 F := First_Formal (Id);
5613 while Present (F) loop
5617 end Install_Formals;
5619 ---------------------------------
5620 -- Is_Non_Overriding_Operation --
5621 ---------------------------------
5623 function Is_Non_Overriding_Operation
5624 (Prev_E : Entity_Id;
5625 New_E : Entity_Id) return Boolean
5629 G_Typ : Entity_Id := Empty;
5631 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
5632 -- If F_Type is a derived type associated with a generic actual subtype,
5633 -- then return its Generic_Parent_Type attribute, else return Empty.
5635 function Types_Correspond
5636 (P_Type : Entity_Id;
5637 N_Type : Entity_Id) return Boolean;
5638 -- Returns true if and only if the types (or designated types in the
5639 -- case of anonymous access types) are the same or N_Type is derived
5640 -- directly or indirectly from P_Type.
5642 -----------------------------
5643 -- Get_Generic_Parent_Type --
5644 -----------------------------
5646 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
5651 if Is_Derived_Type (F_Typ)
5652 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
5654 -- The tree must be traversed to determine the parent subtype in
5655 -- the generic unit, which unfortunately isn't always available
5656 -- via semantic attributes. ??? (Note: The use of Original_Node
5657 -- is needed for cases where a full derived type has been
5660 Indic := Subtype_Indication
5661 (Type_Definition (Original_Node (Parent (F_Typ))));
5663 if Nkind (Indic) = N_Subtype_Indication then
5664 G_Typ := Entity (Subtype_Mark (Indic));
5666 G_Typ := Entity (Indic);
5669 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
5670 and then Present (Generic_Parent_Type (Parent (G_Typ)))
5672 return Generic_Parent_Type (Parent (G_Typ));
5677 end Get_Generic_Parent_Type;
5679 ----------------------
5680 -- Types_Correspond --
5681 ----------------------
5683 function Types_Correspond
5684 (P_Type : Entity_Id;
5685 N_Type : Entity_Id) return Boolean
5687 Prev_Type : Entity_Id := Base_Type (P_Type);
5688 New_Type : Entity_Id := Base_Type (N_Type);
5691 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
5692 Prev_Type := Designated_Type (Prev_Type);
5695 if Ekind (New_Type) = E_Anonymous_Access_Type then
5696 New_Type := Designated_Type (New_Type);
5699 if Prev_Type = New_Type then
5702 elsif not Is_Class_Wide_Type (New_Type) then
5703 while Etype (New_Type) /= New_Type loop
5704 New_Type := Etype (New_Type);
5705 if New_Type = Prev_Type then
5711 end Types_Correspond;
5713 -- Start of processing for Is_Non_Overriding_Operation
5716 -- In the case where both operations are implicit derived subprograms
5717 -- then neither overrides the other. This can only occur in certain
5718 -- obscure cases (e.g., derivation from homographs created in a generic
5721 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
5724 elsif Ekind (Current_Scope) = E_Package
5725 and then Is_Generic_Instance (Current_Scope)
5726 and then In_Private_Part (Current_Scope)
5727 and then Comes_From_Source (New_E)
5729 -- We examine the formals and result subtype of the inherited
5730 -- operation, to determine whether their type is derived from (the
5731 -- instance of) a generic type.
5733 Formal := First_Formal (Prev_E);
5735 while Present (Formal) loop
5736 F_Typ := Base_Type (Etype (Formal));
5738 if Ekind (F_Typ) = E_Anonymous_Access_Type then
5739 F_Typ := Designated_Type (F_Typ);
5742 G_Typ := Get_Generic_Parent_Type (F_Typ);
5744 Next_Formal (Formal);
5747 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
5748 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
5755 -- If the generic type is a private type, then the original
5756 -- operation was not overriding in the generic, because there was
5757 -- no primitive operation to override.
5759 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
5760 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
5761 N_Formal_Private_Type_Definition
5765 -- The generic parent type is the ancestor of a formal derived
5766 -- type declaration. We need to check whether it has a primitive
5767 -- operation that should be overridden by New_E in the generic.
5771 P_Formal : Entity_Id;
5772 N_Formal : Entity_Id;
5776 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
5779 while Present (Prim_Elt) loop
5780 P_Prim := Node (Prim_Elt);
5782 if Chars (P_Prim) = Chars (New_E)
5783 and then Ekind (P_Prim) = Ekind (New_E)
5785 P_Formal := First_Formal (P_Prim);
5786 N_Formal := First_Formal (New_E);
5787 while Present (P_Formal) and then Present (N_Formal) loop
5788 P_Typ := Etype (P_Formal);
5789 N_Typ := Etype (N_Formal);
5791 if not Types_Correspond (P_Typ, N_Typ) then
5795 Next_Entity (P_Formal);
5796 Next_Entity (N_Formal);
5799 -- Found a matching primitive operation belonging to the
5800 -- formal ancestor type, so the new subprogram is
5804 and then No (N_Formal)
5805 and then (Ekind (New_E) /= E_Function
5808 (Etype (P_Prim), Etype (New_E)))
5814 Next_Elmt (Prim_Elt);
5817 -- If no match found, then the new subprogram does not
5818 -- override in the generic (nor in the instance).
5826 end Is_Non_Overriding_Operation;
5828 ------------------------------
5829 -- Make_Inequality_Operator --
5830 ------------------------------
5832 -- S is the defining identifier of an equality operator. We build a
5833 -- subprogram declaration with the right signature. This operation is
5834 -- intrinsic, because it is always expanded as the negation of the
5835 -- call to the equality function.
5837 procedure Make_Inequality_Operator (S : Entity_Id) is
5838 Loc : constant Source_Ptr := Sloc (S);
5841 Op_Name : Entity_Id;
5843 FF : constant Entity_Id := First_Formal (S);
5844 NF : constant Entity_Id := Next_Formal (FF);
5847 -- Check that equality was properly defined, ignore call if not
5854 A : constant Entity_Id :=
5855 Make_Defining_Identifier (Sloc (FF),
5856 Chars => Chars (FF));
5858 B : constant Entity_Id :=
5859 Make_Defining_Identifier (Sloc (NF),
5860 Chars => Chars (NF));
5863 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
5865 Formals := New_List (
5866 Make_Parameter_Specification (Loc,
5867 Defining_Identifier => A,
5869 New_Reference_To (Etype (First_Formal (S)),
5870 Sloc (Etype (First_Formal (S))))),
5872 Make_Parameter_Specification (Loc,
5873 Defining_Identifier => B,
5875 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
5876 Sloc (Etype (Next_Formal (First_Formal (S)))))));
5879 Make_Subprogram_Declaration (Loc,
5881 Make_Function_Specification (Loc,
5882 Defining_Unit_Name => Op_Name,
5883 Parameter_Specifications => Formals,
5884 Result_Definition =>
5885 New_Reference_To (Standard_Boolean, Loc)));
5887 -- Insert inequality right after equality if it is explicit or after
5888 -- the derived type when implicit. These entities are created only
5889 -- for visibility purposes, and eventually replaced in the course of
5890 -- expansion, so they do not need to be attached to the tree and seen
5891 -- by the back-end. Keeping them internal also avoids spurious
5892 -- freezing problems. The declaration is inserted in the tree for
5893 -- analysis, and removed afterwards. If the equality operator comes
5894 -- from an explicit declaration, attach the inequality immediately
5895 -- after. Else the equality is inherited from a derived type
5896 -- declaration, so insert inequality after that declaration.
5898 if No (Alias (S)) then
5899 Insert_After (Unit_Declaration_Node (S), Decl);
5900 elsif Is_List_Member (Parent (S)) then
5901 Insert_After (Parent (S), Decl);
5903 Insert_After (Parent (Etype (First_Formal (S))), Decl);
5906 Mark_Rewrite_Insertion (Decl);
5907 Set_Is_Intrinsic_Subprogram (Op_Name);
5910 Set_Has_Completion (Op_Name);
5911 Set_Corresponding_Equality (Op_Name, S);
5912 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
5914 end Make_Inequality_Operator;
5916 ----------------------
5917 -- May_Need_Actuals --
5918 ----------------------
5920 procedure May_Need_Actuals (Fun : Entity_Id) is
5925 F := First_Formal (Fun);
5927 while Present (F) loop
5928 if No (Default_Value (F)) then
5936 Set_Needs_No_Actuals (Fun, B);
5937 end May_Need_Actuals;
5939 ---------------------
5940 -- Mode_Conformant --
5941 ---------------------
5943 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
5946 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
5948 end Mode_Conformant;
5950 ---------------------------
5951 -- New_Overloaded_Entity --
5952 ---------------------------
5954 procedure New_Overloaded_Entity
5956 Derived_Type : Entity_Id := Empty)
5958 Overridden_Subp : Entity_Id := Empty;
5959 -- Set if the current scope has an operation that is type-conformant
5960 -- with S, and becomes hidden by S.
5962 Is_Primitive_Subp : Boolean;
5963 -- Set to True if the new subprogram is primitive
5966 -- Entity that S overrides
5968 Prev_Vis : Entity_Id := Empty;
5969 -- Predecessor of E in Homonym chain
5971 procedure Check_For_Primitive_Subprogram
5972 (Is_Primitive : out Boolean;
5973 Is_Overriding : Boolean := False);
5974 -- If the subprogram being analyzed is a primitive operation of the type
5975 -- of a formal or result, set the Has_Primitive_Operations flag on the
5976 -- type, and set Is_Primitive to True (otherwise set to False). Set the
5977 -- corresponding flag on the entity itself for later use.
5979 procedure Check_Synchronized_Overriding
5980 (Def_Id : Entity_Id;
5981 First_Hom : Entity_Id;
5982 Overridden_Subp : out Entity_Id);
5983 -- First determine if Def_Id is an entry or a subprogram either defined
5984 -- in the scope of a task or protected type, or is a primitive of such
5985 -- a type. Check whether Def_Id overrides a subprogram of an interface
5986 -- implemented by the synchronized type, return the overridden entity
5989 function Is_Private_Declaration (E : Entity_Id) return Boolean;
5990 -- Check that E is declared in the private part of the current package,
5991 -- or in the package body, where it may hide a previous declaration.
5992 -- We can't use In_Private_Part by itself because this flag is also
5993 -- set when freezing entities, so we must examine the place of the
5994 -- declaration in the tree, and recognize wrapper packages as well.
5996 ------------------------------------
5997 -- Check_For_Primitive_Subprogram --
5998 ------------------------------------
6000 procedure Check_For_Primitive_Subprogram
6001 (Is_Primitive : out Boolean;
6002 Is_Overriding : Boolean := False)
6008 function Visible_Part_Type (T : Entity_Id) return Boolean;
6009 -- Returns true if T is declared in the visible part of
6010 -- the current package scope; otherwise returns false.
6011 -- Assumes that T is declared in a package.
6013 procedure Check_Private_Overriding (T : Entity_Id);
6014 -- Checks that if a primitive abstract subprogram of a visible
6015 -- abstract type is declared in a private part, then it must
6016 -- override an abstract subprogram declared in the visible part.
6017 -- Also checks that if a primitive function with a controlling
6018 -- result is declared in a private part, then it must override
6019 -- a function declared in the visible part.
6021 ------------------------------
6022 -- Check_Private_Overriding --
6023 ------------------------------
6025 procedure Check_Private_Overriding (T : Entity_Id) is
6027 if Ekind (Current_Scope) = E_Package
6028 and then In_Private_Part (Current_Scope)
6029 and then Visible_Part_Type (T)
6030 and then not In_Instance
6032 if Is_Abstract_Type (T)
6033 and then Is_Abstract_Subprogram (S)
6034 and then (not Is_Overriding
6035 or else not Is_Abstract_Subprogram (E))
6037 Error_Msg_N ("abstract subprograms must be visible "
6038 & "(RM 3.9.3(10))!", S);
6040 elsif Ekind (S) = E_Function
6041 and then Is_Tagged_Type (T)
6042 and then T = Base_Type (Etype (S))
6043 and then not Is_Overriding
6046 ("private function with tagged result must"
6047 & " override visible-part function", S);
6049 ("\move subprogram to the visible part"
6050 & " (RM 3.9.3(10))", S);
6053 end Check_Private_Overriding;
6055 -----------------------
6056 -- Visible_Part_Type --
6057 -----------------------
6059 function Visible_Part_Type (T : Entity_Id) return Boolean is
6060 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
6064 -- If the entity is a private type, then it must be
6065 -- declared in a visible part.
6067 if Ekind (T) in Private_Kind then
6071 -- Otherwise, we traverse the visible part looking for its
6072 -- corresponding declaration. We cannot use the declaration
6073 -- node directly because in the private part the entity of a
6074 -- private type is the one in the full view, which does not
6075 -- indicate that it is the completion of something visible.
6077 N := First (Visible_Declarations (Specification (P)));
6078 while Present (N) loop
6079 if Nkind (N) = N_Full_Type_Declaration
6080 and then Present (Defining_Identifier (N))
6081 and then T = Defining_Identifier (N)
6085 elsif (Nkind (N) = N_Private_Type_Declaration
6087 Nkind (N) = N_Private_Extension_Declaration)
6088 and then Present (Defining_Identifier (N))
6089 and then T = Full_View (Defining_Identifier (N))
6098 end Visible_Part_Type;
6100 -- Start of processing for Check_For_Primitive_Subprogram
6103 Is_Primitive := False;
6105 if not Comes_From_Source (S) then
6108 -- If subprogram is at library level, it is not primitive operation
6110 elsif Current_Scope = Standard_Standard then
6113 elsif ((Ekind (Current_Scope) = E_Package
6114 or else Ekind (Current_Scope) = E_Generic_Package)
6115 and then not In_Package_Body (Current_Scope))
6116 or else Is_Overriding
6118 -- For function, check return type
6120 if Ekind (S) = E_Function then
6121 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
6122 F_Typ := Designated_Type (Etype (S));
6127 B_Typ := Base_Type (F_Typ);
6129 if Scope (B_Typ) = Current_Scope
6130 and then not Is_Class_Wide_Type (B_Typ)
6131 and then not Is_Generic_Type (B_Typ)
6133 Is_Primitive := True;
6134 Set_Has_Primitive_Operations (B_Typ);
6135 Set_Is_Primitive (S);
6136 Check_Private_Overriding (B_Typ);
6140 -- For all subprograms, check formals
6142 Formal := First_Formal (S);
6143 while Present (Formal) loop
6144 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
6145 F_Typ := Designated_Type (Etype (Formal));
6147 F_Typ := Etype (Formal);
6150 B_Typ := Base_Type (F_Typ);
6152 if Ekind (B_Typ) = E_Access_Subtype then
6153 B_Typ := Base_Type (B_Typ);
6156 if Scope (B_Typ) = Current_Scope
6157 and then not Is_Class_Wide_Type (B_Typ)
6158 and then not Is_Generic_Type (B_Typ)
6160 Is_Primitive := True;
6161 Set_Is_Primitive (S);
6162 Set_Has_Primitive_Operations (B_Typ);
6163 Check_Private_Overriding (B_Typ);
6166 Next_Formal (Formal);
6169 end Check_For_Primitive_Subprogram;
6171 -----------------------------------
6172 -- Check_Synchronized_Overriding --
6173 -----------------------------------
6175 procedure Check_Synchronized_Overriding
6176 (Def_Id : Entity_Id;
6177 First_Hom : Entity_Id;
6178 Overridden_Subp : out Entity_Id)
6180 Formal_Typ : Entity_Id;
6181 Ifaces_List : Elist_Id;
6186 Overridden_Subp := Empty;
6188 -- Def_Id must be an entry or a subprogram
6190 if Ekind (Def_Id) /= E_Entry
6191 and then Ekind (Def_Id) /= E_Function
6192 and then Ekind (Def_Id) /= E_Procedure
6197 -- Search for the concurrent declaration since it contains the list
6198 -- of all implemented interfaces. In this case, the subprogram is
6199 -- declared within the scope of a protected or a task type.
6201 if Present (Scope (Def_Id))
6202 and then Is_Concurrent_Type (Scope (Def_Id))
6203 and then not Is_Generic_Actual_Type (Scope (Def_Id))
6205 Typ := Scope (Def_Id);
6208 -- The subprogram may be a primitive of a concurrent type
6210 elsif Present (First_Formal (Def_Id)) then
6211 Formal_Typ := Etype (First_Formal (Def_Id));
6213 if Is_Concurrent_Type (Formal_Typ)
6214 and then not Is_Generic_Actual_Type (Formal_Typ)
6219 -- This case occurs when the concurrent type is declared within
6220 -- a generic unit. As a result the corresponding record has been
6221 -- built and used as the type of the first formal, we just have
6222 -- to retrieve the corresponding concurrent type.
6224 elsif Is_Concurrent_Record_Type (Formal_Typ)
6225 and then Present (Corresponding_Concurrent_Type (Formal_Typ))
6227 Typ := Corresponding_Concurrent_Type (Formal_Typ);
6237 -- Gather all limited, protected and task interfaces that Typ
6238 -- implements. There is no overriding to check if is an inherited
6239 -- operation in a type derivation on for a generic actual.
6241 if Nkind (Parent (Typ)) /= N_Full_Type_Declaration
6242 and then Nkind (Parent (Def_Id)) /= N_Subtype_Declaration
6243 and then Nkind (Parent (Def_Id)) /= N_Task_Type_Declaration
6244 and then Nkind (Parent (Def_Id)) /= N_Protected_Type_Declaration
6246 Collect_Abstract_Interfaces (Typ, Ifaces_List);
6248 if not Is_Empty_Elmt_List (Ifaces_List) then
6250 Find_Overridden_Synchronized_Primitive
6251 (Def_Id, First_Hom, Ifaces_List, In_Scope);
6254 end Check_Synchronized_Overriding;
6256 ----------------------------
6257 -- Is_Private_Declaration --
6258 ----------------------------
6260 function Is_Private_Declaration (E : Entity_Id) return Boolean is
6261 Priv_Decls : List_Id;
6262 Decl : constant Node_Id := Unit_Declaration_Node (E);
6265 if Is_Package_Or_Generic_Package (Current_Scope)
6266 and then In_Private_Part (Current_Scope)
6269 Private_Declarations (
6270 Specification (Unit_Declaration_Node (Current_Scope)));
6272 return In_Package_Body (Current_Scope)
6274 (Is_List_Member (Decl)
6275 and then List_Containing (Decl) = Priv_Decls)
6276 or else (Nkind (Parent (Decl)) = N_Package_Specification
6277 and then not Is_Compilation_Unit (
6278 Defining_Entity (Parent (Decl)))
6279 and then List_Containing (Parent (Parent (Decl)))
6284 end Is_Private_Declaration;
6286 -- Start of processing for New_Overloaded_Entity
6289 -- We need to look for an entity that S may override. This must be a
6290 -- homonym in the current scope, so we look for the first homonym of
6291 -- S in the current scope as the starting point for the search.
6293 E := Current_Entity_In_Scope (S);
6295 -- If there is no homonym then this is definitely not overriding
6298 Enter_Overloaded_Entity (S);
6299 Check_Dispatching_Operation (S, Empty);
6300 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6302 -- If subprogram has an explicit declaration, check whether it
6303 -- has an overriding indicator.
6305 if Comes_From_Source (S) then
6306 Check_Synchronized_Overriding (S, Homonym (S), Overridden_Subp);
6307 Check_Overriding_Indicator
6308 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6311 -- If there is a homonym that is not overloadable, then we have an
6312 -- error, except for the special cases checked explicitly below.
6314 elsif not Is_Overloadable (E) then
6316 -- Check for spurious conflict produced by a subprogram that has the
6317 -- same name as that of the enclosing generic package. The conflict
6318 -- occurs within an instance, between the subprogram and the renaming
6319 -- declaration for the package. After the subprogram, the package
6320 -- renaming declaration becomes hidden.
6322 if Ekind (E) = E_Package
6323 and then Present (Renamed_Object (E))
6324 and then Renamed_Object (E) = Current_Scope
6325 and then Nkind (Parent (Renamed_Object (E))) =
6326 N_Package_Specification
6327 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
6330 Set_Is_Immediately_Visible (E, False);
6331 Enter_Overloaded_Entity (S);
6332 Set_Homonym (S, Homonym (E));
6333 Check_Dispatching_Operation (S, Empty);
6334 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
6336 -- If the subprogram is implicit it is hidden by the previous
6337 -- declaration. However if it is dispatching, it must appear in the
6338 -- dispatch table anyway, because it can be dispatched to even if it
6339 -- cannot be called directly.
6341 elsif Present (Alias (S))
6342 and then not Comes_From_Source (S)
6344 Set_Scope (S, Current_Scope);
6346 if Is_Dispatching_Operation (Alias (S)) then
6347 Check_Dispatching_Operation (S, Empty);
6353 Error_Msg_Sloc := Sloc (E);
6355 -- Generate message,with useful additionalwarning if in generic
6357 if Is_Generic_Unit (E) then
6358 Error_Msg_N ("previous generic unit cannot be overloaded", S);
6359 Error_Msg_N ("\& conflicts with declaration#", S);
6361 Error_Msg_N ("& conflicts with declaration#", S);
6367 -- E exists and is overloadable
6370 -- Ada 2005 (AI-251): Derivation of abstract interface primitives
6371 -- need no check against the homonym chain. They are directly added
6372 -- to the list of primitive operations of Derived_Type.
6374 if Ada_Version >= Ada_05
6375 and then Present (Derived_Type)
6376 and then Is_Dispatching_Operation (Alias (S))
6377 and then Present (Find_Dispatching_Type (Alias (S)))
6378 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
6379 and then not Is_Predefined_Dispatching_Operation (Alias (S))
6381 goto Add_New_Entity;
6384 Check_Synchronized_Overriding (S, E, Overridden_Subp);
6386 -- Loop through E and its homonyms to determine if any of them is
6387 -- the candidate for overriding by S.
6389 while Present (E) loop
6391 -- Definitely not interesting if not in the current scope
6393 if Scope (E) /= Current_Scope then
6396 -- Check if we have type conformance
6398 elsif Type_Conformant (E, S) then
6400 -- If the old and new entities have the same profile and one
6401 -- is not the body of the other, then this is an error, unless
6402 -- one of them is implicitly declared.
6404 -- There are some cases when both can be implicit, for example
6405 -- when both a literal and a function that overrides it are
6406 -- inherited in a derivation, or when an inhertited operation
6407 -- of a tagged full type overrides the inherited operation of
6408 -- a private extension. Ada 83 had a special rule for the the
6409 -- literal case. In Ada95, the later implicit operation hides
6410 -- the former, and the literal is always the former. In the
6411 -- odd case where both are derived operations declared at the
6412 -- same point, both operations should be declared, and in that
6413 -- case we bypass the following test and proceed to the next
6414 -- part (this can only occur for certain obscure cases
6415 -- involving homographs in instances and can't occur for
6416 -- dispatching operations ???). Note that the following
6417 -- condition is less than clear. For example, it's not at all
6418 -- clear why there's a test for E_Entry here. ???
6420 if Present (Alias (S))
6421 and then (No (Alias (E))
6422 or else Comes_From_Source (E)
6423 or else Is_Dispatching_Operation (E))
6425 (Ekind (E) = E_Entry
6426 or else Ekind (E) /= E_Enumeration_Literal)
6428 -- When an derived operation is overloaded it may be due to
6429 -- the fact that the full view of a private extension
6430 -- re-inherits. It has to be dealt with.
6432 if Is_Package_Or_Generic_Package (Current_Scope)
6433 and then In_Private_Part (Current_Scope)
6435 Check_Operation_From_Private_View (S, E);
6438 -- In any case the implicit operation remains hidden by
6439 -- the existing declaration, which is overriding.
6441 Set_Is_Overriding_Operation (E);
6443 if Comes_From_Source (E) then
6444 Check_Overriding_Indicator (E, S, Is_Primitive => False);
6446 -- Indicate that E overrides the operation from which
6449 if Present (Alias (S)) then
6450 Set_Overridden_Operation (E, Alias (S));
6452 Set_Overridden_Operation (E, S);
6458 -- Within an instance, the renaming declarations for
6459 -- actual subprograms may become ambiguous, but they do
6460 -- not hide each other.
6462 elsif Ekind (E) /= E_Entry
6463 and then not Comes_From_Source (E)
6464 and then not Is_Generic_Instance (E)
6465 and then (Present (Alias (E))
6466 or else Is_Intrinsic_Subprogram (E))
6467 and then (not In_Instance
6468 or else No (Parent (E))
6469 or else Nkind (Unit_Declaration_Node (E)) /=
6470 N_Subprogram_Renaming_Declaration)
6472 -- A subprogram child unit is not allowed to override
6473 -- an inherited subprogram (10.1.1(20)).
6475 if Is_Child_Unit (S) then
6477 ("child unit overrides inherited subprogram in parent",
6482 if Is_Non_Overriding_Operation (E, S) then
6483 Enter_Overloaded_Entity (S);
6484 if No (Derived_Type)
6485 or else Is_Tagged_Type (Derived_Type)
6487 Check_Dispatching_Operation (S, Empty);
6493 -- E is a derived operation or an internal operator which
6494 -- is being overridden. Remove E from further visibility.
6495 -- Furthermore, if E is a dispatching operation, it must be
6496 -- replaced in the list of primitive operations of its type
6497 -- (see Override_Dispatching_Operation).
6499 Overridden_Subp := E;
6505 Prev := First_Entity (Current_Scope);
6507 while Present (Prev)
6508 and then Next_Entity (Prev) /= E
6513 -- It is possible for E to be in the current scope and
6514 -- yet not in the entity chain. This can only occur in a
6515 -- generic context where E is an implicit concatenation
6516 -- in the formal part, because in a generic body the
6517 -- entity chain starts with the formals.
6520 (Present (Prev) or else Chars (E) = Name_Op_Concat);
6522 -- E must be removed both from the entity_list of the
6523 -- current scope, and from the visibility chain
6525 if Debug_Flag_E then
6526 Write_Str ("Override implicit operation ");
6527 Write_Int (Int (E));
6531 -- If E is a predefined concatenation, it stands for four
6532 -- different operations. As a result, a single explicit
6533 -- declaration does not hide it. In a possible ambiguous
6534 -- situation, Disambiguate chooses the user-defined op,
6535 -- so it is correct to retain the previous internal one.
6537 if Chars (E) /= Name_Op_Concat
6538 or else Ekind (E) /= E_Operator
6540 -- For nondispatching derived operations that are
6541 -- overridden by a subprogram declared in the private
6542 -- part of a package, we retain the derived
6543 -- subprogram but mark it as not immediately visible.
6544 -- If the derived operation was declared in the
6545 -- visible part then this ensures that it will still
6546 -- be visible outside the package with the proper
6547 -- signature (calls from outside must also be
6548 -- directed to this version rather than the
6549 -- overriding one, unlike the dispatching case).
6550 -- Calls from inside the package will still resolve
6551 -- to the overriding subprogram since the derived one
6552 -- is marked as not visible within the package.
6554 -- If the private operation is dispatching, we achieve
6555 -- the overriding by keeping the implicit operation
6556 -- but setting its alias to be the overriding one. In
6557 -- this fashion the proper body is executed in all
6558 -- cases, but the original signature is used outside
6561 -- If the overriding is not in the private part, we
6562 -- remove the implicit operation altogether.
6564 if Is_Private_Declaration (S) then
6566 if not Is_Dispatching_Operation (E) then
6567 Set_Is_Immediately_Visible (E, False);
6569 -- Work done in Override_Dispatching_Operation,
6570 -- so nothing else need to be done here.
6576 -- Find predecessor of E in Homonym chain
6578 if E = Current_Entity (E) then
6581 Prev_Vis := Current_Entity (E);
6582 while Homonym (Prev_Vis) /= E loop
6583 Prev_Vis := Homonym (Prev_Vis);
6587 if Prev_Vis /= Empty then
6589 -- Skip E in the visibility chain
6591 Set_Homonym (Prev_Vis, Homonym (E));
6594 Set_Name_Entity_Id (Chars (E), Homonym (E));
6597 Set_Next_Entity (Prev, Next_Entity (E));
6599 if No (Next_Entity (Prev)) then
6600 Set_Last_Entity (Current_Scope, Prev);
6606 Enter_Overloaded_Entity (S);
6607 Set_Is_Overriding_Operation (S);
6608 Check_Overriding_Indicator (S, E, Is_Primitive => True);
6610 -- Indicate that S overrides the operation from which
6613 if Comes_From_Source (S) then
6614 if Present (Alias (E)) then
6615 Set_Overridden_Operation (S, Alias (E));
6617 Set_Overridden_Operation (S, E);
6621 if Is_Dispatching_Operation (E) then
6623 -- An overriding dispatching subprogram inherits the
6624 -- convention of the overridden subprogram (by
6627 Set_Convention (S, Convention (E));
6628 Check_Dispatching_Operation (S, E);
6631 Check_Dispatching_Operation (S, Empty);
6634 Check_For_Primitive_Subprogram
6635 (Is_Primitive_Subp, Is_Overriding => True);
6636 goto Check_Inequality;
6639 -- Apparent redeclarations in instances can occur when two
6640 -- formal types get the same actual type. The subprograms in
6641 -- in the instance are legal, even if not callable from the
6642 -- outside. Calls from within are disambiguated elsewhere.
6643 -- For dispatching operations in the visible part, the usual
6644 -- rules apply, and operations with the same profile are not
6647 elsif (In_Instance_Visible_Part
6648 and then not Is_Dispatching_Operation (E))
6649 or else In_Instance_Not_Visible
6653 -- Here we have a real error (identical profile)
6656 Error_Msg_Sloc := Sloc (E);
6658 -- Avoid cascaded errors if the entity appears in
6659 -- subsequent calls.
6661 Set_Scope (S, Current_Scope);
6663 -- Generate error, with extra useful warning for the case
6664 -- of a generic instance with no completion.
6666 if Is_Generic_Instance (S)
6667 and then not Has_Completion (E)
6670 ("instantiation cannot provide body for&", S);
6671 Error_Msg_N ("\& conflicts with declaration#", S);
6673 Error_Msg_N ("& conflicts with declaration#", S);
6680 -- If one subprogram has an access parameter and the other
6681 -- a parameter of an access type, calls to either might be
6682 -- ambiguous. Verify that parameters match except for the
6683 -- access parameter.
6685 if May_Hide_Profile then
6690 F1 := First_Formal (S);
6691 F2 := First_Formal (E);
6692 while Present (F1) and then Present (F2) loop
6693 if Is_Access_Type (Etype (F1)) then
6694 if not Is_Access_Type (Etype (F2))
6695 or else not Conforming_Types
6696 (Designated_Type (Etype (F1)),
6697 Designated_Type (Etype (F2)),
6700 May_Hide_Profile := False;
6704 not Conforming_Types
6705 (Etype (F1), Etype (F2), Type_Conformant)
6707 May_Hide_Profile := False;
6718 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
6729 -- On exit, we know that S is a new entity
6731 Enter_Overloaded_Entity (S);
6732 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
6733 Check_Overriding_Indicator
6734 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
6736 -- If S is a derived operation for an untagged type then by
6737 -- definition it's not a dispatching operation (even if the parent
6738 -- operation was dispatching), so we don't call
6739 -- Check_Dispatching_Operation in that case.
6741 if No (Derived_Type)
6742 or else Is_Tagged_Type (Derived_Type)
6744 Check_Dispatching_Operation (S, Empty);
6748 -- If this is a user-defined equality operator that is not a derived
6749 -- subprogram, create the corresponding inequality. If the operation is
6750 -- dispatching, the expansion is done elsewhere, and we do not create
6751 -- an explicit inequality operation.
6753 <<Check_Inequality>>
6754 if Chars (S) = Name_Op_Eq
6755 and then Etype (S) = Standard_Boolean
6756 and then Present (Parent (S))
6757 and then not Is_Dispatching_Operation (S)
6759 Make_Inequality_Operator (S);
6761 end New_Overloaded_Entity;
6763 ---------------------
6764 -- Process_Formals --
6765 ---------------------
6767 procedure Process_Formals
6769 Related_Nod : Node_Id)
6771 Param_Spec : Node_Id;
6773 Formal_Type : Entity_Id;
6777 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
6778 -- Check whether the default has a class-wide type. After analysis the
6779 -- default has the type of the formal, so we must also check explicitly
6780 -- for an access attribute.
6782 ---------------------------
6783 -- Is_Class_Wide_Default --
6784 ---------------------------
6786 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
6788 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
6789 or else (Nkind (D) = N_Attribute_Reference
6790 and then Attribute_Name (D) = Name_Access
6791 and then Is_Class_Wide_Type (Etype (Prefix (D))));
6792 end Is_Class_Wide_Default;
6794 -- Start of processing for Process_Formals
6797 -- In order to prevent premature use of the formals in the same formal
6798 -- part, the Ekind is left undefined until all default expressions are
6799 -- analyzed. The Ekind is established in a separate loop at the end.
6801 Param_Spec := First (T);
6802 while Present (Param_Spec) loop
6803 Formal := Defining_Identifier (Param_Spec);
6804 Set_Never_Set_In_Source (Formal, True);
6805 Enter_Name (Formal);
6807 -- Case of ordinary parameters
6809 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
6810 Find_Type (Parameter_Type (Param_Spec));
6811 Ptype := Parameter_Type (Param_Spec);
6813 if Ptype = Error then
6817 Formal_Type := Entity (Ptype);
6819 if Is_Incomplete_Type (Formal_Type)
6821 (Is_Class_Wide_Type (Formal_Type)
6822 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
6824 -- Ada 2005 (AI-326): Tagged incomplete types allowed
6826 if Is_Tagged_Type (Formal_Type) then
6829 -- Special handling of Value_Type for CIL case
6831 elsif Is_Value_Type (Formal_Type) then
6834 elsif Nkind (Parent (T)) /= N_Access_Function_Definition
6835 and then Nkind (Parent (T)) /= N_Access_Procedure_Definition
6837 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
6839 -- An incomplete type that is not tagged is allowed in an
6840 -- access-to-subprogram type only if it is a local declaration
6841 -- with a forthcoming completion (3.10.1 (9.2/2)).
6843 elsif Scope (Formal_Type) /= Scope (Current_Scope) then
6845 ("invalid use of limited view of type", Param_Spec);
6848 elsif Ekind (Formal_Type) = E_Void then
6849 Error_Msg_NE ("premature use of&",
6850 Parameter_Type (Param_Spec), Formal_Type);
6853 -- Ada 2005 (AI-231): Create and decorate an internal subtype
6854 -- declaration corresponding to the null-excluding type of the
6855 -- formal in the enclosing scope. Finally, replace the parameter
6856 -- type of the formal with the internal subtype.
6858 if Ada_Version >= Ada_05
6859 and then Null_Exclusion_Present (Param_Spec)
6861 if not Is_Access_Type (Formal_Type) then
6863 ("`NOT NULL` allowed only for an access type", Param_Spec);
6866 if Can_Never_Be_Null (Formal_Type)
6867 and then Comes_From_Source (Related_Nod)
6870 ("`NOT NULL` not allowed (& already excludes null)",
6876 Create_Null_Excluding_Itype
6878 Related_Nod => Related_Nod,
6879 Scope_Id => Scope (Current_Scope));
6881 -- If the designated type of the itype is an itype we
6882 -- decorate it with the Has_Delayed_Freeze attribute to
6883 -- avoid problems with the backend.
6886 -- type T is access procedure;
6887 -- procedure Op (O : not null T);
6889 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
6890 Set_Has_Delayed_Freeze (Formal_Type);
6895 -- An access formal type
6899 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
6901 -- No need to continue if we already notified errors
6903 if not Present (Formal_Type) then
6907 -- Ada 2005 (AI-254)
6910 AD : constant Node_Id :=
6911 Access_To_Subprogram_Definition
6912 (Parameter_Type (Param_Spec));
6914 if Present (AD) and then Protected_Present (AD) then
6916 Replace_Anonymous_Access_To_Protected_Subprogram
6922 Set_Etype (Formal, Formal_Type);
6923 Default := Expression (Param_Spec);
6925 if Present (Default) then
6926 if Out_Present (Param_Spec) then
6928 ("default initialization only allowed for IN parameters",
6932 -- Do the special preanalysis of the expression (see section on
6933 -- "Handling of Default Expressions" in the spec of package Sem).
6935 Analyze_Per_Use_Expression (Default, Formal_Type);
6937 -- Check that the designated type of an access parameter's default
6938 -- is not a class-wide type unless the parameter's designated type
6939 -- is also class-wide.
6941 if Ekind (Formal_Type) = E_Anonymous_Access_Type
6942 and then not From_With_Type (Formal_Type)
6943 and then Is_Class_Wide_Default (Default)
6944 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
6947 ("access to class-wide expression not allowed here", Default);
6951 -- Ada 2005 (AI-231): Static checks
6953 if Ada_Version >= Ada_05
6954 and then Is_Access_Type (Etype (Formal))
6955 and then Can_Never_Be_Null (Etype (Formal))
6957 Null_Exclusion_Static_Checks (Param_Spec);
6964 -- If this is the formal part of a function specification, analyze the
6965 -- subtype mark in the context where the formals are visible but not
6966 -- yet usable, and may hide outer homographs.
6968 if Nkind (Related_Nod) = N_Function_Specification then
6969 Analyze_Return_Type (Related_Nod);
6972 -- Now set the kind (mode) of each formal
6974 Param_Spec := First (T);
6976 while Present (Param_Spec) loop
6977 Formal := Defining_Identifier (Param_Spec);
6978 Set_Formal_Mode (Formal);
6980 if Ekind (Formal) = E_In_Parameter then
6981 Set_Default_Value (Formal, Expression (Param_Spec));
6983 if Present (Expression (Param_Spec)) then
6984 Default := Expression (Param_Spec);
6986 if Is_Scalar_Type (Etype (Default)) then
6988 (Parameter_Type (Param_Spec)) /= N_Access_Definition
6990 Formal_Type := Entity (Parameter_Type (Param_Spec));
6993 Formal_Type := Access_Definition
6994 (Related_Nod, Parameter_Type (Param_Spec));
6997 Apply_Scalar_Range_Check (Default, Formal_Type);
7005 end Process_Formals;
7007 ----------------------------
7008 -- Reference_Body_Formals --
7009 ----------------------------
7011 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
7016 if Error_Posted (Spec) then
7020 -- Iterate over both lists. They may be of different lengths if the two
7021 -- specs are not conformant.
7023 Fs := First_Formal (Spec);
7024 Fb := First_Formal (Bod);
7025 while Present (Fs) and then Present (Fb) loop
7026 Generate_Reference (Fs, Fb, 'b');
7029 Style.Check_Identifier (Fb, Fs);
7032 Set_Spec_Entity (Fb, Fs);
7033 Set_Referenced (Fs, False);
7037 end Reference_Body_Formals;
7039 -------------------------
7040 -- Set_Actual_Subtypes --
7041 -------------------------
7043 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
7044 Loc : constant Source_Ptr := Sloc (N);
7048 First_Stmt : Node_Id := Empty;
7049 AS_Needed : Boolean;
7052 -- If this is an emtpy initialization procedure, no need to create
7053 -- actual subtypes (small optimization).
7055 if Ekind (Subp) = E_Procedure
7056 and then Is_Null_Init_Proc (Subp)
7061 Formal := First_Formal (Subp);
7062 while Present (Formal) loop
7063 T := Etype (Formal);
7065 -- We never need an actual subtype for a constrained formal
7067 if Is_Constrained (T) then
7070 -- If we have unknown discriminants, then we do not need an actual
7071 -- subtype, or more accurately we cannot figure it out! Note that
7072 -- all class-wide types have unknown discriminants.
7074 elsif Has_Unknown_Discriminants (T) then
7077 -- At this stage we have an unconstrained type that may need an
7078 -- actual subtype. For sure the actual subtype is needed if we have
7079 -- an unconstrained array type.
7081 elsif Is_Array_Type (T) then
7084 -- The only other case needing an actual subtype is an unconstrained
7085 -- record type which is an IN parameter (we cannot generate actual
7086 -- subtypes for the OUT or IN OUT case, since an assignment can
7087 -- change the discriminant values. However we exclude the case of
7088 -- initialization procedures, since discriminants are handled very
7089 -- specially in this context, see the section entitled "Handling of
7090 -- Discriminants" in Einfo.
7092 -- We also exclude the case of Discrim_SO_Functions (functions used
7093 -- in front end layout mode for size/offset values), since in such
7094 -- functions only discriminants are referenced, and not only are such
7095 -- subtypes not needed, but they cannot always be generated, because
7096 -- of order of elaboration issues.
7098 elsif Is_Record_Type (T)
7099 and then Ekind (Formal) = E_In_Parameter
7100 and then Chars (Formal) /= Name_uInit
7101 and then not Is_Unchecked_Union (T)
7102 and then not Is_Discrim_SO_Function (Subp)
7106 -- All other cases do not need an actual subtype
7112 -- Generate actual subtypes for unconstrained arrays and
7113 -- unconstrained discriminated records.
7116 if Nkind (N) = N_Accept_Statement then
7118 -- If expansion is active, The formal is replaced by a local
7119 -- variable that renames the corresponding entry of the
7120 -- parameter block, and it is this local variable that may
7121 -- require an actual subtype.
7123 if Expander_Active then
7124 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
7126 Decl := Build_Actual_Subtype (T, Formal);
7129 if Present (Handled_Statement_Sequence (N)) then
7131 First (Statements (Handled_Statement_Sequence (N)));
7132 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
7133 Mark_Rewrite_Insertion (Decl);
7135 -- If the accept statement has no body, there will be no
7136 -- reference to the actuals, so no need to compute actual
7143 Decl := Build_Actual_Subtype (T, Formal);
7144 Prepend (Decl, Declarations (N));
7145 Mark_Rewrite_Insertion (Decl);
7148 -- The declaration uses the bounds of an existing object, and
7149 -- therefore needs no constraint checks.
7151 Analyze (Decl, Suppress => All_Checks);
7153 -- We need to freeze manually the generated type when it is
7154 -- inserted anywhere else than in a declarative part.
7156 if Present (First_Stmt) then
7157 Insert_List_Before_And_Analyze (First_Stmt,
7158 Freeze_Entity (Defining_Identifier (Decl), Loc));
7161 if Nkind (N) = N_Accept_Statement
7162 and then Expander_Active
7164 Set_Actual_Subtype (Renamed_Object (Formal),
7165 Defining_Identifier (Decl));
7167 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
7171 Next_Formal (Formal);
7173 end Set_Actual_Subtypes;
7175 ---------------------
7176 -- Set_Formal_Mode --
7177 ---------------------
7179 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
7180 Spec : constant Node_Id := Parent (Formal_Id);
7183 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
7184 -- since we ensure that corresponding actuals are always valid at the
7185 -- point of the call.
7187 if Out_Present (Spec) then
7188 if Ekind (Scope (Formal_Id)) = E_Function
7189 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
7191 Error_Msg_N ("functions can only have IN parameters", Spec);
7192 Set_Ekind (Formal_Id, E_In_Parameter);
7194 elsif In_Present (Spec) then
7195 Set_Ekind (Formal_Id, E_In_Out_Parameter);
7198 Set_Ekind (Formal_Id, E_Out_Parameter);
7199 Set_Never_Set_In_Source (Formal_Id, True);
7200 Set_Is_True_Constant (Formal_Id, False);
7201 Set_Current_Value (Formal_Id, Empty);
7205 Set_Ekind (Formal_Id, E_In_Parameter);
7208 -- Set Is_Known_Non_Null for access parameters since the language
7209 -- guarantees that access parameters are always non-null. We also set
7210 -- Can_Never_Be_Null, since there is no way to change the value.
7212 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
7214 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
7215 -- null; In Ada 2005, only if then null_exclusion is explicit.
7217 if Ada_Version < Ada_05
7218 or else Can_Never_Be_Null (Etype (Formal_Id))
7220 Set_Is_Known_Non_Null (Formal_Id);
7221 Set_Can_Never_Be_Null (Formal_Id);
7224 -- Ada 2005 (AI-231): Null-exclusion access subtype
7226 elsif Is_Access_Type (Etype (Formal_Id))
7227 and then Can_Never_Be_Null (Etype (Formal_Id))
7229 Set_Is_Known_Non_Null (Formal_Id);
7232 Set_Mechanism (Formal_Id, Default_Mechanism);
7233 Set_Formal_Validity (Formal_Id);
7234 end Set_Formal_Mode;
7236 -------------------------
7237 -- Set_Formal_Validity --
7238 -------------------------
7240 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
7242 -- If no validity checking, then we cannot assume anything about the
7243 -- validity of parameters, since we do not know there is any checking
7244 -- of the validity on the call side.
7246 if not Validity_Checks_On then
7249 -- If validity checking for parameters is enabled, this means we are
7250 -- not supposed to make any assumptions about argument values.
7252 elsif Validity_Check_Parameters then
7255 -- If we are checking in parameters, we will assume that the caller is
7256 -- also checking parameters, so we can assume the parameter is valid.
7258 elsif Ekind (Formal_Id) = E_In_Parameter
7259 and then Validity_Check_In_Params
7261 Set_Is_Known_Valid (Formal_Id, True);
7263 -- Similar treatment for IN OUT parameters
7265 elsif Ekind (Formal_Id) = E_In_Out_Parameter
7266 and then Validity_Check_In_Out_Params
7268 Set_Is_Known_Valid (Formal_Id, True);
7270 end Set_Formal_Validity;
7272 ------------------------
7273 -- Subtype_Conformant --
7274 ------------------------
7276 function Subtype_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7279 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result);
7281 end Subtype_Conformant;
7283 ---------------------
7284 -- Type_Conformant --
7285 ---------------------
7287 function Type_Conformant
7288 (New_Id : Entity_Id;
7290 Skip_Controlling_Formals : Boolean := False) return Boolean
7294 May_Hide_Profile := False;
7297 (New_Id, Old_Id, Type_Conformant, False, Result,
7298 Skip_Controlling_Formals => Skip_Controlling_Formals);
7300 end Type_Conformant;
7302 -------------------------------
7303 -- Valid_Operator_Definition --
7304 -------------------------------
7306 procedure Valid_Operator_Definition (Designator : Entity_Id) is
7309 Id : constant Name_Id := Chars (Designator);
7313 F := First_Formal (Designator);
7314 while Present (F) loop
7317 if Present (Default_Value (F)) then
7319 ("default values not allowed for operator parameters",
7326 -- Verify that user-defined operators have proper number of arguments
7327 -- First case of operators which can only be unary
7330 or else Id = Name_Op_Abs
7334 -- Case of operators which can be unary or binary
7336 elsif Id = Name_Op_Add
7337 or Id = Name_Op_Subtract
7339 N_OK := (N in 1 .. 2);
7341 -- All other operators can only be binary
7349 ("incorrect number of arguments for operator", Designator);
7353 and then Base_Type (Etype (Designator)) = Standard_Boolean
7354 and then not Is_Intrinsic_Subprogram (Designator)
7357 ("explicit definition of inequality not allowed", Designator);
7359 end Valid_Operator_Definition;