1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, 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 Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Disp; use Exp_Disp;
40 with Exp_Tss; use Exp_Tss;
41 with Exp_Util; use Exp_Util;
42 with Fname; use Fname;
43 with Freeze; use Freeze;
44 with Ghost; use Ghost;
45 with Inline; use Inline;
46 with Itypes; use Itypes;
47 with Lib.Xref; use Lib.Xref;
48 with Layout; use Layout;
49 with Namet; use Namet;
51 with Nlists; use Nlists;
52 with Nmake; use Nmake;
54 with Output; use Output;
55 with Restrict; use Restrict;
56 with Rident; use Rident;
57 with Rtsfind; use Rtsfind;
59 with Sem_Aux; use Sem_Aux;
60 with Sem_Cat; use Sem_Cat;
61 with Sem_Ch3; use Sem_Ch3;
62 with Sem_Ch4; use Sem_Ch4;
63 with Sem_Ch5; use Sem_Ch5;
64 with Sem_Ch8; use Sem_Ch8;
65 with Sem_Ch9; use Sem_Ch9;
66 with Sem_Ch10; use Sem_Ch10;
67 with Sem_Ch12; use Sem_Ch12;
68 with Sem_Ch13; use Sem_Ch13;
69 with Sem_Dim; use Sem_Dim;
70 with Sem_Disp; use Sem_Disp;
71 with Sem_Dist; use Sem_Dist;
72 with Sem_Elim; use Sem_Elim;
73 with Sem_Eval; use Sem_Eval;
74 with Sem_Mech; use Sem_Mech;
75 with Sem_Prag; use Sem_Prag;
76 with Sem_Res; use Sem_Res;
77 with Sem_Util; use Sem_Util;
78 with Sem_Type; use Sem_Type;
79 with Sem_Warn; use Sem_Warn;
80 with Sinput; use Sinput;
81 with Stand; use Stand;
82 with Sinfo; use Sinfo;
83 with Sinfo.CN; use Sinfo.CN;
84 with Snames; use Snames;
85 with Stringt; use Stringt;
87 with Stylesw; use Stylesw;
88 with Tbuild; use Tbuild;
89 with Uintp; use Uintp;
90 with Urealp; use Urealp;
91 with Validsw; use Validsw;
93 package body Sem_Ch6 is
95 May_Hide_Profile : Boolean := False;
96 -- This flag is used to indicate that two formals in two subprograms being
97 -- checked for conformance differ only in that one is an access parameter
98 -- while the other is of a general access type with the same designated
99 -- type. In this case, if the rest of the signatures match, a call to
100 -- either subprogram may be ambiguous, which is worth a warning. The flag
101 -- is set in Compatible_Types, and the warning emitted in
102 -- New_Overloaded_Entity.
104 -----------------------
105 -- Local Subprograms --
106 -----------------------
108 procedure Analyze_Function_Return (N : Node_Id);
109 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
110 -- applies to a [generic] function.
112 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
113 -- Analyze a generic subprogram body. N is the body to be analyzed, and
114 -- Gen_Id is the defining entity Id for the corresponding spec.
116 procedure Analyze_Null_Procedure
118 Is_Completion : out Boolean);
119 -- A null procedure can be a declaration or (Ada 2012) a completion
121 procedure Analyze_Return_Statement (N : Node_Id);
122 -- Common processing for simple and extended return statements
124 procedure Analyze_Return_Type (N : Node_Id);
125 -- Subsidiary to Process_Formals: analyze subtype mark in function
126 -- specification in a context where the formals are visible and hide
129 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
130 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
131 -- that we can use RETURN but not skip the debug output at the end.
133 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
134 -- Returns true if Subp can override a predefined operator.
136 procedure Check_Conformance
139 Ctype : Conformance_Type;
141 Conforms : out Boolean;
142 Err_Loc : Node_Id := Empty;
143 Get_Inst : Boolean := False;
144 Skip_Controlling_Formals : Boolean := False);
145 -- Given two entities, this procedure checks that the profiles associated
146 -- with these entities meet the conformance criterion given by the third
147 -- parameter. If they conform, Conforms is set True and control returns
148 -- to the caller. If they do not conform, Conforms is set to False, and
149 -- in addition, if Errmsg is True on the call, proper messages are output
150 -- to complain about the conformance failure. If Err_Loc is non_Empty
151 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
152 -- error messages are placed on the appropriate part of the construct
153 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
154 -- against a formal access-to-subprogram type so Get_Instance_Of must
157 procedure Check_Limited_Return
161 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
162 -- types. Used only for simple return statements. Expr is the expression
165 procedure Check_Subprogram_Order (N : Node_Id);
166 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
167 -- the alpha ordering rule for N if this ordering requirement applicable.
169 procedure Check_Returns
173 Proc : Entity_Id := Empty);
174 -- Called to check for missing return statements in a function body, or for
175 -- returns present in a procedure body which has No_Return set. HSS is the
176 -- handled statement sequence for the subprogram body. This procedure
177 -- checks all flow paths to make sure they either have return (Mode = 'F',
178 -- used for functions) or do not have a return (Mode = 'P', used for
179 -- No_Return procedures). The flag Err is set if there are any control
180 -- paths not explicitly terminated by a return in the function case, and is
181 -- True otherwise. Proc is the entity for the procedure case and is used
182 -- in posting the warning message.
184 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
185 -- In Ada 2012, a primitive equality operator on an untagged record type
186 -- must appear before the type is frozen, and have the same visibility as
187 -- that of the type. This procedure checks that this rule is met, and
188 -- otherwise emits an error on the subprogram declaration and a warning
189 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
190 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
191 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
192 -- is set, otherwise the call has no effect.
194 procedure Enter_Overloaded_Entity (S : Entity_Id);
195 -- This procedure makes S, a new overloaded entity, into the first visible
196 -- entity with that name.
198 function Is_Non_Overriding_Operation
200 New_E : Entity_Id) return Boolean;
201 -- Enforce the rule given in 12.3(18): a private operation in an instance
202 -- overrides an inherited operation only if the corresponding operation
203 -- was overriding in the generic. This needs to be checked for primitive
204 -- operations of types derived (in the generic unit) from formal private
205 -- or formal derived types.
207 procedure Make_Inequality_Operator (S : Entity_Id);
208 -- Create the declaration for an inequality operator that is implicitly
209 -- created by a user-defined equality operator that yields a boolean.
211 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
212 -- Formal_Id is an formal parameter entity. This procedure deals with
213 -- setting the proper validity status for this entity, which depends on
214 -- the kind of parameter and the validity checking mode.
216 ---------------------------------------------
217 -- Analyze_Abstract_Subprogram_Declaration --
218 ---------------------------------------------
220 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
221 Scop : constant Entity_Id := Current_Scope;
222 Subp_Id : constant Entity_Id :=
223 Analyze_Subprogram_Specification (Specification (N));
226 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
228 Generate_Definition (Subp_Id);
230 Set_Is_Abstract_Subprogram (Subp_Id);
231 New_Overloaded_Entity (Subp_Id);
232 Check_Delayed_Subprogram (Subp_Id);
234 Set_Categorization_From_Scope (Subp_Id, Scop);
236 -- An abstract subprogram declared within a Ghost region is rendered
237 -- Ghost (SPARK RM 6.9(2)).
239 if Ghost_Mode > None then
240 Set_Is_Ghost_Entity (Subp_Id);
243 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
244 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
246 -- Issue a warning if the abstract subprogram is neither a dispatching
247 -- operation nor an operation that overrides an inherited subprogram or
248 -- predefined operator, since this most likely indicates a mistake.
250 elsif Warn_On_Redundant_Constructs
251 and then not Is_Dispatching_Operation (Subp_Id)
252 and then not Present (Overridden_Operation (Subp_Id))
253 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
254 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
257 ("abstract subprogram is not dispatching or overriding?r?", N);
260 Generate_Reference_To_Formals (Subp_Id);
261 Check_Eliminated (Subp_Id);
263 if Has_Aspects (N) then
264 Analyze_Aspect_Specifications (N, Subp_Id);
266 end Analyze_Abstract_Subprogram_Declaration;
268 ---------------------------------
269 -- Analyze_Expression_Function --
270 ---------------------------------
272 procedure Analyze_Expression_Function (N : Node_Id) is
273 Expr : constant Node_Id := Expression (N);
274 Loc : constant Source_Ptr := Sloc (N);
275 LocX : constant Source_Ptr := Sloc (Expr);
276 Spec : constant Node_Id := Specification (N);
286 -- If the expression is a completion, Prev is the entity whose
287 -- declaration is completed. Def_Id is needed to analyze the spec.
290 -- This is one of the occasions on which we transform the tree during
291 -- semantic analysis. If this is a completion, transform the expression
292 -- function into an equivalent subprogram body, and analyze it.
294 -- Expression functions are inlined unconditionally. The back-end will
295 -- determine whether this is possible.
297 Inline_Processing_Required := True;
299 -- Create a specification for the generated body. This must be done
300 -- prior to the analysis of the initial declaration.
302 New_Spec := Copy_Subprogram_Spec (Spec);
303 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
305 -- If there are previous overloadable entities with the same name,
306 -- check whether any of them is completed by the expression function.
307 -- In a generic context a formal subprogram has no completion.
310 and then Is_Overloadable (Prev)
311 and then not Is_Formal_Subprogram (Prev)
313 Def_Id := Analyze_Subprogram_Specification (Spec);
314 Prev := Find_Corresponding_Spec (N);
316 -- The previous entity may be an expression function as well, in
317 -- which case the redeclaration is illegal.
320 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
321 N_Expression_Function
323 Error_Msg_Sloc := Sloc (Prev);
324 Error_Msg_N ("& conflicts with declaration#", Def_Id);
329 Ret := Make_Simple_Return_Statement (LocX, Expression (N));
332 Make_Subprogram_Body (Loc,
333 Specification => New_Spec,
334 Declarations => Empty_List,
335 Handled_Statement_Sequence =>
336 Make_Handled_Sequence_Of_Statements (LocX,
337 Statements => New_List (Ret)));
338 Set_Was_Expression_Function (New_Body);
340 -- If the expression completes a generic subprogram, we must create a
341 -- separate node for the body, because at instantiation the original
342 -- node of the generic copy must be a generic subprogram body, and
343 -- cannot be a expression function. Otherwise we just rewrite the
344 -- expression with the non-generic body.
346 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
347 Insert_After (N, New_Body);
349 -- Propagate any aspects or pragmas that apply to the expression
350 -- function to the proper body when the expression function acts
353 if Has_Aspects (N) then
354 Move_Aspects (N, To => New_Body);
357 Relocate_Pragmas_To_Body (New_Body);
359 Rewrite (N, Make_Null_Statement (Loc));
360 Set_Has_Completion (Prev, False);
363 Set_Is_Inlined (Prev);
365 -- If the expression function is a completion, the previous declaration
366 -- must come from source. We know already that it appears in the current
367 -- scope. The entity itself may be internally created if within a body
371 and then Comes_From_Source (Parent (Prev))
372 and then not Is_Formal_Subprogram (Prev)
374 Set_Has_Completion (Prev, False);
375 Set_Is_Inlined (Prev);
377 -- An expression function that is a completion freezes the
378 -- expression. This means freezing the return type, and if it is
379 -- an access type, freezing its designated type as well.
381 -- Note that we cannot defer this freezing to the analysis of the
382 -- expression itself, because a freeze node might appear in a nested
383 -- scope, leading to an elaboration order issue in gigi.
385 Freeze_Before (N, Etype (Prev));
387 if Is_Access_Type (Etype (Prev)) then
388 Freeze_Before (N, Designated_Type (Etype (Prev)));
391 -- For navigation purposes, indicate that the function is a body
393 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
394 Rewrite (N, New_Body);
396 -- Remove any existing aspects from the original node because the act
397 -- of rewriting causes the list to be shared between the two nodes.
399 Orig_N := Original_Node (N);
400 Remove_Aspects (Orig_N);
402 -- Propagate any pragmas that apply to the expression function to the
403 -- proper body when the expression function acts as a completion.
404 -- Aspects are automatically transfered because of node rewriting.
406 Relocate_Pragmas_To_Body (N);
409 -- Once the aspects of the generated body have been analyzed, create
410 -- a copy for ASIS purposes and associate it with the original node.
412 if Has_Aspects (N) then
413 Set_Aspect_Specifications (Orig_N,
414 New_Copy_List_Tree (Aspect_Specifications (N)));
417 -- Prev is the previous entity with the same name, but it is can
418 -- be an unrelated spec that is not completed by the expression
419 -- function. In that case the relevant entity is the one in the body.
420 -- Not clear that the backend can inline it in this case ???
422 if Has_Completion (Prev) then
424 -- The formals of the expression function are body formals,
425 -- and do not appear in the ali file, which will only contain
426 -- references to the formals of the original subprogram spec.
433 F1 := First_Formal (Def_Id);
434 F2 := First_Formal (Prev);
436 while Present (F1) loop
437 Set_Spec_Entity (F1, F2);
444 Set_Is_Inlined (Defining_Entity (New_Body));
447 -- If this is not a completion, create both a declaration and a body, so
448 -- that the expression can be inlined whenever possible.
451 -- An expression function that is not a completion is not a
452 -- subprogram declaration, and thus cannot appear in a protected
455 if Nkind (Parent (N)) = N_Protected_Definition then
457 ("an expression function is not a legal protected operation", N);
460 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
462 -- Remove any existing aspects from the original node because the act
463 -- of rewriting causes the list to be shared between the two nodes.
465 Orig_N := Original_Node (N);
466 Remove_Aspects (Orig_N);
470 -- Once the aspects of the generated spec have been analyzed, create
471 -- a copy for ASIS purposes and associate it with the original node.
473 if Has_Aspects (N) then
474 Set_Aspect_Specifications (Orig_N,
475 New_Copy_List_Tree (Aspect_Specifications (N)));
478 -- If aspect SPARK_Mode was specified on the body, it needs to be
479 -- repeated both on the generated spec and the body.
481 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
483 if Present (Asp) then
484 Asp := New_Copy_Tree (Asp);
485 Set_Analyzed (Asp, False);
486 Set_Aspect_Specifications (New_Body, New_List (Asp));
489 Def_Id := Defining_Entity (N);
491 -- Within a generic pre-analyze the original expression for name
492 -- capture. The body is also generated but plays no role in
493 -- this because it is not part of the original source.
495 if Inside_A_Generic then
496 Set_Has_Completion (Def_Id);
498 Install_Formals (Def_Id);
499 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
503 Set_Is_Inlined (Defining_Entity (N));
505 -- If the expression function is Ghost, mark its body entity as
506 -- Ghost too. This avoids spurious errors on unanalyzed body entities
507 -- of expression functions, which are not yet marked as ghost, yet
508 -- identified as the Corresponding_Body of the ghost declaration.
510 if Is_Ghost_Entity (Def_Id) then
511 Set_Is_Ghost_Entity (Defining_Entity (New_Body));
514 -- Establish the linkages between the spec and the body. These are
515 -- used when the expression function acts as the prefix of attribute
516 -- 'Access in order to freeze the original expression which has been
517 -- moved to the generated body.
519 Set_Corresponding_Body (N, Defining_Entity (New_Body));
520 Set_Corresponding_Spec (New_Body, Defining_Entity (N));
522 -- To prevent premature freeze action, insert the new body at the end
523 -- of the current declarations, or at the end of the package spec.
524 -- However, resolve usage names now, to prevent spurious visibility
525 -- on later entities. Note that the function can now be called in
526 -- the current declarative part, which will appear to be prior to
527 -- the presence of the body in the code. There are nevertheless no
528 -- order of elaboration issues because all name resolution has taken
529 -- place at the point of declaration.
532 Decls : List_Id := List_Containing (N);
533 Expr : constant Node_Id := Expression (Ret);
534 Par : constant Node_Id := Parent (Decls);
535 Typ : constant Entity_Id := Etype (Def_Id);
538 -- If this is a wrapper created for in an instance for a formal
539 -- subprogram, insert body after declaration, to be analyzed when
540 -- the enclosing instance is analyzed.
543 and then Is_Generic_Actual_Subprogram (Defining_Entity (N))
545 Insert_After (N, New_Body);
548 if Nkind (Par) = N_Package_Specification
549 and then Decls = Visible_Declarations (Par)
550 and then Present (Private_Declarations (Par))
551 and then not Is_Empty_List (Private_Declarations (Par))
553 Decls := Private_Declarations (Par);
556 Insert_After (Last (Decls), New_Body);
558 -- Preanalyze the expression for name capture, except in an
559 -- instance, where this has been done during generic analysis,
560 -- and will be redone when analyzing the body.
562 Set_Parent (Expr, Ret);
564 Install_Formals (Def_Id);
566 if not In_Instance then
567 Preanalyze_Spec_Expression (Expr, Typ);
568 Check_Limited_Return (Original_Node (N), Expr, Typ);
576 -- If the return expression is a static constant, we suppress warning
577 -- messages on unused formals, which in most cases will be noise.
579 Set_Is_Trivial_Subprogram
580 (Defining_Entity (New_Body), Is_OK_Static_Expression (Expr));
581 end Analyze_Expression_Function;
583 ----------------------------------------
584 -- Analyze_Extended_Return_Statement --
585 ----------------------------------------
587 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
589 Check_Compiler_Unit ("extended return statement", N);
590 Analyze_Return_Statement (N);
591 end Analyze_Extended_Return_Statement;
593 ----------------------------
594 -- Analyze_Function_Call --
595 ----------------------------
597 procedure Analyze_Function_Call (N : Node_Id) is
598 Actuals : constant List_Id := Parameter_Associations (N);
599 Func_Nam : constant Node_Id := Name (N);
605 -- A call of the form A.B (X) may be an Ada 2005 call, which is
606 -- rewritten as B (A, X). If the rewriting is successful, the call
607 -- has been analyzed and we just return.
609 if Nkind (Func_Nam) = N_Selected_Component
610 and then Name (N) /= Func_Nam
611 and then Is_Rewrite_Substitution (N)
612 and then Present (Etype (N))
617 -- If error analyzing name, then set Any_Type as result type and return
619 if Etype (Func_Nam) = Any_Type then
620 Set_Etype (N, Any_Type);
624 -- Otherwise analyze the parameters
626 if Present (Actuals) then
627 Actual := First (Actuals);
628 while Present (Actual) loop
630 Check_Parameterless_Call (Actual);
636 end Analyze_Function_Call;
638 -----------------------------
639 -- Analyze_Function_Return --
640 -----------------------------
642 procedure Analyze_Function_Return (N : Node_Id) is
643 Loc : constant Source_Ptr := Sloc (N);
644 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
645 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
647 R_Type : constant Entity_Id := Etype (Scope_Id);
648 -- Function result subtype
650 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
651 -- Apply legality rule of 6.5 (8.2) to the access discriminants of an
652 -- aggregate in a return statement.
654 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
655 -- Check that the return_subtype_indication properly matches the result
656 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
658 -----------------------------------
659 -- Check_Aggregate_Accessibility --
660 -----------------------------------
662 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
663 Typ : constant Entity_Id := Etype (Aggr);
670 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
671 Discr := First_Discriminant (Typ);
672 Assoc := First (Component_Associations (Aggr));
673 while Present (Discr) loop
674 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
675 Expr := Expression (Assoc);
676 if Nkind (Expr) = N_Attribute_Reference
677 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
679 Obj := Prefix (Expr);
680 while Nkind_In (Obj, N_Indexed_Component,
681 N_Selected_Component)
686 -- No check needed for an aliased formal.
687 -- A run-time check may still be needed ???
689 if Is_Entity_Name (Obj)
690 and then Is_Formal (Entity (Obj))
691 and then Is_Aliased (Entity (Obj))
695 elsif Object_Access_Level (Obj) >
696 Scope_Depth (Scope (Scope_Id))
699 ("access discriminant in return aggregate would be "
700 & "a dangling reference", Obj);
705 Next_Discriminant (Discr);
708 end Check_Aggregate_Accessibility;
710 -------------------------------------
711 -- Check_Return_Subtype_Indication --
712 -------------------------------------
714 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
715 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
717 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
718 -- Subtype given in the extended return statement (must match R_Type)
720 Subtype_Ind : constant Node_Id :=
721 Object_Definition (Original_Node (Obj_Decl));
723 R_Type_Is_Anon_Access : constant Boolean :=
725 E_Anonymous_Access_Subprogram_Type,
726 E_Anonymous_Access_Protected_Subprogram_Type,
727 E_Anonymous_Access_Type);
728 -- True if return type of the function is an anonymous access type
729 -- Can't we make Is_Anonymous_Access_Type in einfo ???
731 R_Stm_Type_Is_Anon_Access : constant Boolean :=
732 Ekind_In (R_Stm_Type,
733 E_Anonymous_Access_Subprogram_Type,
734 E_Anonymous_Access_Protected_Subprogram_Type,
735 E_Anonymous_Access_Type);
736 -- True if type of the return object is an anonymous access type
738 procedure Error_No_Match (N : Node_Id);
739 -- Output error messages for case where types do not statically
740 -- match. N is the location for the messages.
746 procedure Error_No_Match (N : Node_Id) is
749 ("subtype must statically match function result subtype", N);
751 if not Predicates_Match (R_Stm_Type, R_Type) then
752 Error_Msg_Node_2 := R_Type;
754 ("\predicate of& does not match predicate of&",
759 -- Start of processing for Check_Return_Subtype_Indication
762 -- First, avoid cascaded errors
764 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
768 -- "return access T" case; check that the return statement also has
769 -- "access T", and that the subtypes statically match:
770 -- if this is an access to subprogram the signatures must match.
772 if R_Type_Is_Anon_Access then
773 if R_Stm_Type_Is_Anon_Access then
775 Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
777 if Base_Type (Designated_Type (R_Stm_Type)) /=
778 Base_Type (Designated_Type (R_Type))
779 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
781 Error_No_Match (Subtype_Mark (Subtype_Ind));
785 -- For two anonymous access to subprogram types, the
786 -- types themselves must be type conformant.
788 if not Conforming_Types
789 (R_Stm_Type, R_Type, Fully_Conformant)
791 Error_No_Match (Subtype_Ind);
796 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
799 -- If the return object is of an anonymous access type, then report
800 -- an error if the function's result type is not also anonymous.
802 elsif R_Stm_Type_Is_Anon_Access then
803 pragma Assert (not R_Type_Is_Anon_Access);
804 Error_Msg_N ("anonymous access not allowed for function with "
805 & "named access result", Subtype_Ind);
807 -- Subtype indication case: check that the return object's type is
808 -- covered by the result type, and that the subtypes statically match
809 -- when the result subtype is constrained. Also handle record types
810 -- with unknown discriminants for which we have built the underlying
811 -- record view. Coverage is needed to allow specific-type return
812 -- objects when the result type is class-wide (see AI05-32).
814 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
815 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
819 Underlying_Record_View (Base_Type (R_Stm_Type))))
821 -- A null exclusion may be present on the return type, on the
822 -- function specification, on the object declaration or on the
825 if Is_Access_Type (R_Type)
827 (Can_Never_Be_Null (R_Type)
828 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
829 Can_Never_Be_Null (R_Stm_Type)
831 Error_No_Match (Subtype_Ind);
834 -- AI05-103: for elementary types, subtypes must statically match
836 if Is_Constrained (R_Type)
837 or else Is_Access_Type (R_Type)
839 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
840 Error_No_Match (Subtype_Ind);
844 -- All remaining cases are illegal
846 -- Note: previous versions of this subprogram allowed the return
847 -- value to be the ancestor of the return type if the return type
848 -- was a null extension. This was plainly incorrect.
852 ("wrong type for return_subtype_indication", Subtype_Ind);
854 end Check_Return_Subtype_Indication;
856 ---------------------
857 -- Local Variables --
858 ---------------------
863 -- Start of processing for Analyze_Function_Return
866 Set_Return_Present (Scope_Id);
868 if Nkind (N) = N_Simple_Return_Statement then
869 Expr := Expression (N);
871 -- Guard against a malformed expression. The parser may have tried to
872 -- recover but the node is not analyzable.
874 if Nkind (Expr) = N_Error then
875 Set_Etype (Expr, Any_Type);
876 Expander_Mode_Save_And_Set (False);
880 -- The resolution of a controlled [extension] aggregate associated
881 -- with a return statement creates a temporary which needs to be
882 -- finalized on function exit. Wrap the return statement inside a
883 -- block so that the finalization machinery can detect this case.
884 -- This early expansion is done only when the return statement is
885 -- not part of a handled sequence of statements.
887 if Nkind_In (Expr, N_Aggregate,
888 N_Extension_Aggregate)
889 and then Needs_Finalization (R_Type)
890 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
893 Make_Block_Statement (Loc,
894 Handled_Statement_Sequence =>
895 Make_Handled_Sequence_Of_Statements (Loc,
896 Statements => New_List (Relocate_Node (N)))));
904 -- Ada 2005 (AI-251): If the type of the returned object is
905 -- an access to an interface type then we add an implicit type
906 -- conversion to force the displacement of the "this" pointer to
907 -- reference the secondary dispatch table. We cannot delay the
908 -- generation of this implicit conversion until the expansion
909 -- because in this case the type resolution changes the decoration
910 -- of the expression node to match R_Type; by contrast, if the
911 -- returned object is a class-wide interface type then it is too
912 -- early to generate here the implicit conversion since the return
913 -- statement may be rewritten by the expander into an extended
914 -- return statement whose expansion takes care of adding the
915 -- implicit type conversion to displace the pointer to the object.
918 and then Serious_Errors_Detected = 0
919 and then Is_Access_Type (R_Type)
920 and then Nkind (Expr) /= N_Null
921 and then Is_Interface (Designated_Type (R_Type))
922 and then Is_Progenitor (Designated_Type (R_Type),
923 Designated_Type (Etype (Expr)))
925 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
929 Resolve (Expr, R_Type);
930 Check_Limited_Return (N, Expr, R_Type);
932 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
933 Check_Aggregate_Accessibility (Expr);
937 -- RETURN only allowed in SPARK as the last statement in function
939 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
941 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
942 or else Present (Next (N)))
944 Check_SPARK_05_Restriction
945 ("RETURN should be the last statement in function", N);
949 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
950 Obj_Decl := Last (Return_Object_Declarations (N));
952 -- Analyze parts specific to extended_return_statement:
955 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
956 HSS : constant Node_Id := Handled_Statement_Sequence (N);
959 Expr := Expression (Obj_Decl);
961 -- Note: The check for OK_For_Limited_Init will happen in
962 -- Analyze_Object_Declaration; we treat it as a normal
963 -- object declaration.
965 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
968 Check_Return_Subtype_Indication (Obj_Decl);
970 if Present (HSS) then
973 if Present (Exception_Handlers (HSS)) then
975 -- ???Has_Nested_Block_With_Handler needs to be set.
976 -- Probably by creating an actual N_Block_Statement.
977 -- Probably in Expand.
983 -- Mark the return object as referenced, since the return is an
984 -- implicit reference of the object.
986 Set_Referenced (Defining_Identifier (Obj_Decl));
988 Check_References (Stm_Entity);
990 -- Check RM 6.5 (5.9/3)
993 if Ada_Version < Ada_2012 then
995 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
996 -- Can it really happen (extended return???)
999 ("aliased only allowed for limited return objects "
1000 & "in Ada 2012??", N);
1002 elsif not Is_Limited_View (R_Type) then
1004 ("aliased only allowed for limited return objects", N);
1010 -- Case of Expr present
1014 -- Defend against previous errors
1016 and then Nkind (Expr) /= N_Empty
1017 and then Present (Etype (Expr))
1019 -- Apply constraint check. Note that this is done before the implicit
1020 -- conversion of the expression done for anonymous access types to
1021 -- ensure correct generation of the null-excluding check associated
1022 -- with null-excluding expressions found in return statements.
1024 Apply_Constraint_Check (Expr, R_Type);
1026 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1027 -- type, apply an implicit conversion of the expression to that type
1028 -- to force appropriate static and run-time accessibility checks.
1030 if Ada_Version >= Ada_2005
1031 and then Ekind (R_Type) = E_Anonymous_Access_Type
1033 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1034 Analyze_And_Resolve (Expr, R_Type);
1036 -- If this is a local anonymous access to subprogram, the
1037 -- accessibility check can be applied statically. The return is
1038 -- illegal if the access type of the return expression is declared
1039 -- inside of the subprogram (except if it is the subtype indication
1040 -- of an extended return statement).
1042 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1043 if not Comes_From_Source (Current_Scope)
1044 or else Ekind (Current_Scope) = E_Return_Statement
1049 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1051 Error_Msg_N ("cannot return local access to subprogram", N);
1054 -- The expression cannot be of a formal incomplete type
1056 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1057 and then Is_Generic_Type (Etype (Expr))
1060 ("cannot return expression of a formal incomplete type", N);
1063 -- If the result type is class-wide, then check that the return
1064 -- expression's type is not declared at a deeper level than the
1065 -- function (RM05-6.5(5.6/2)).
1067 if Ada_Version >= Ada_2005
1068 and then Is_Class_Wide_Type (R_Type)
1070 if Type_Access_Level (Etype (Expr)) >
1071 Subprogram_Access_Level (Scope_Id)
1074 ("level of return expression type is deeper than "
1075 & "class-wide function!", Expr);
1079 -- Check incorrect use of dynamically tagged expression
1081 if Is_Tagged_Type (R_Type) then
1082 Check_Dynamically_Tagged_Expression
1088 -- ??? A real run-time accessibility check is needed in cases
1089 -- involving dereferences of access parameters. For now we just
1090 -- check the static cases.
1092 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1093 and then Is_Limited_View (Etype (Scope_Id))
1094 and then Object_Access_Level (Expr) >
1095 Subprogram_Access_Level (Scope_Id)
1097 -- Suppress the message in a generic, where the rewriting
1100 if Inside_A_Generic then
1105 Make_Raise_Program_Error (Loc,
1106 Reason => PE_Accessibility_Check_Failed));
1109 Error_Msg_Warn := SPARK_Mode /= On;
1110 Error_Msg_N ("cannot return a local value by reference<<", N);
1111 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1115 if Known_Null (Expr)
1116 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1117 and then Null_Exclusion_Present (Parent (Scope_Id))
1119 Apply_Compile_Time_Constraint_Error
1121 Msg => "(Ada 2005) null not allowed for "
1122 & "null-excluding return??",
1123 Reason => CE_Null_Not_Allowed);
1126 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1127 -- has no initializing expression.
1129 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1130 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1131 Subprogram_Access_Level (Scope_Id)
1134 ("level of return expression type is deeper than "
1135 & "class-wide function!", Obj_Decl);
1138 end Analyze_Function_Return;
1140 -------------------------------------
1141 -- Analyze_Generic_Subprogram_Body --
1142 -------------------------------------
1144 procedure Analyze_Generic_Subprogram_Body
1148 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1149 Kind : constant Entity_Kind := Ekind (Gen_Id);
1150 Body_Id : Entity_Id;
1155 -- Copy body and disable expansion while analyzing the generic For a
1156 -- stub, do not copy the stub (which would load the proper body), this
1157 -- will be done when the proper body is analyzed.
1159 if Nkind (N) /= N_Subprogram_Body_Stub then
1160 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1163 -- Once the contents of the generic copy and the template are
1164 -- swapped, do the same for their respective aspect specifications.
1166 Exchange_Aspects (N, New_N);
1168 -- Collect all contract-related source pragmas found within the
1169 -- template and attach them to the contract of the subprogram body.
1170 -- This contract is used in the capture of global references within
1173 Create_Generic_Contract (N);
1178 Spec := Specification (N);
1180 -- Within the body of the generic, the subprogram is callable, and
1181 -- behaves like the corresponding non-generic unit.
1183 Body_Id := Defining_Entity (Spec);
1185 if Kind = E_Generic_Procedure
1186 and then Nkind (Spec) /= N_Procedure_Specification
1188 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1191 elsif Kind = E_Generic_Function
1192 and then Nkind (Spec) /= N_Function_Specification
1194 Error_Msg_N ("invalid body for generic function ", Body_Id);
1198 Set_Corresponding_Body (Gen_Decl, Body_Id);
1200 if Has_Completion (Gen_Id)
1201 and then Nkind (Parent (N)) /= N_Subunit
1203 Error_Msg_N ("duplicate generic body", N);
1206 Set_Has_Completion (Gen_Id);
1209 if Nkind (N) = N_Subprogram_Body_Stub then
1210 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1212 Set_Corresponding_Spec (N, Gen_Id);
1215 if Nkind (Parent (N)) = N_Compilation_Unit then
1216 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1219 -- Make generic parameters immediately visible in the body. They are
1220 -- needed to process the formals declarations. Then make the formals
1221 -- visible in a separate step.
1223 Push_Scope (Gen_Id);
1227 First_Ent : Entity_Id;
1230 First_Ent := First_Entity (Gen_Id);
1233 while Present (E) and then not Is_Formal (E) loop
1238 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1240 -- Now generic formals are visible, and the specification can be
1241 -- analyzed, for subsequent conformance check.
1243 Body_Id := Analyze_Subprogram_Specification (Spec);
1245 -- Make formal parameters visible
1249 -- E is the first formal parameter, we loop through the formals
1250 -- installing them so that they will be visible.
1252 Set_First_Entity (Gen_Id, E);
1253 while Present (E) loop
1259 -- Visible generic entity is callable within its own body
1261 Set_Ekind (Gen_Id, Ekind (Body_Id));
1262 Set_Ekind (Body_Id, E_Subprogram_Body);
1263 Set_Convention (Body_Id, Convention (Gen_Id));
1264 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1265 Set_Scope (Body_Id, Scope (Gen_Id));
1267 -- Inherit the "ghostness" of the generic spec. Note that this
1268 -- property is not directly inherited as the body may be subject
1269 -- to a different Ghost assertion policy.
1271 if Ghost_Mode > None or else Is_Ghost_Entity (Gen_Id) then
1272 Set_Is_Ghost_Entity (Body_Id);
1274 -- The Ghost policy in effect at the point of declaration and at
1275 -- the point of completion must match (SPARK RM 6.9(14)).
1277 Check_Ghost_Completion (Gen_Id, Body_Id);
1280 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1282 if Nkind (N) = N_Subprogram_Body_Stub then
1284 -- No body to analyze, so restore state of generic unit
1286 Set_Ekind (Gen_Id, Kind);
1287 Set_Ekind (Body_Id, Kind);
1289 if Present (First_Ent) then
1290 Set_First_Entity (Gen_Id, First_Ent);
1297 -- If this is a compilation unit, it must be made visible explicitly,
1298 -- because the compilation of the declaration, unlike other library
1299 -- unit declarations, does not. If it is not a unit, the following
1300 -- is redundant but harmless.
1302 Set_Is_Immediately_Visible (Gen_Id);
1303 Reference_Body_Formals (Gen_Id, Body_Id);
1305 if Is_Child_Unit (Gen_Id) then
1306 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1309 Set_Actual_Subtypes (N, Current_Scope);
1311 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1312 Set_SPARK_Pragma_Inherited (Body_Id);
1314 -- Analyze any aspect specifications that appear on the generic
1317 if Has_Aspects (N) then
1318 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
1321 Analyze_Declarations (Declarations (N));
1324 -- Process the contract of the subprogram body after all declarations
1325 -- have been analyzed. This ensures that any contract-related pragmas
1326 -- are available through the N_Contract node of the body.
1328 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1330 Analyze (Handled_Statement_Sequence (N));
1331 Save_Global_References (Original_Node (N));
1333 -- Prior to exiting the scope, include generic formals again (if any
1334 -- are present) in the set of local entities.
1336 if Present (First_Ent) then
1337 Set_First_Entity (Gen_Id, First_Ent);
1340 Check_References (Gen_Id);
1343 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1345 Check_Subprogram_Order (N);
1347 -- Outside of its body, unit is generic again
1349 Set_Ekind (Gen_Id, Kind);
1350 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1353 Style.Check_Identifier (Body_Id, Gen_Id);
1357 end Analyze_Generic_Subprogram_Body;
1359 ----------------------------
1360 -- Analyze_Null_Procedure --
1361 ----------------------------
1363 procedure Analyze_Null_Procedure
1365 Is_Completion : out Boolean)
1367 Loc : constant Source_Ptr := Sloc (N);
1368 Spec : constant Node_Id := Specification (N);
1369 Designator : Entity_Id;
1371 Null_Body : Node_Id := Empty;
1375 -- Capture the profile of the null procedure before analysis, for
1376 -- expansion at the freeze point and at each point of call. The body is
1377 -- used if the procedure has preconditions, or if it is a completion. In
1378 -- the first case the body is analyzed at the freeze point, in the other
1379 -- it replaces the null procedure declaration.
1382 Make_Subprogram_Body (Loc,
1383 Specification => New_Copy_Tree (Spec),
1384 Declarations => New_List,
1385 Handled_Statement_Sequence =>
1386 Make_Handled_Sequence_Of_Statements (Loc,
1387 Statements => New_List (Make_Null_Statement (Loc))));
1389 -- Create new entities for body and formals
1391 Set_Defining_Unit_Name (Specification (Null_Body),
1392 Make_Defining_Identifier
1393 (Sloc (Defining_Entity (N)),
1394 Chars (Defining_Entity (N))));
1396 Form := First (Parameter_Specifications (Specification (Null_Body)));
1397 while Present (Form) loop
1398 Set_Defining_Identifier (Form,
1399 Make_Defining_Identifier
1400 (Sloc (Defining_Identifier (Form)),
1401 Chars (Defining_Identifier (Form))));
1405 -- Determine whether the null procedure may be a completion of a generic
1406 -- suprogram, in which case we use the new null body as the completion
1407 -- and set minimal semantic information on the original declaration,
1408 -- which is rewritten as a null statement.
1410 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1412 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1413 Insert_Before (N, Null_Body);
1414 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1416 Rewrite (N, Make_Null_Statement (Loc));
1417 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1418 Is_Completion := True;
1422 -- Resolve the types of the formals now, because the freeze point
1423 -- may appear in a different context, e.g. an instantiation.
1425 Form := First (Parameter_Specifications (Specification (Null_Body)));
1426 while Present (Form) loop
1427 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1428 Find_Type (Parameter_Type (Form));
1431 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
1433 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1436 -- The case of a null procedure with a formal that is an
1437 -- access_to_subprogram type, and that is used as an actual
1438 -- in an instantiation is left to the enthusiastic reader.
1447 -- If there are previous overloadable entities with the same name,
1448 -- check whether any of them is completed by the null procedure.
1450 if Present (Prev) and then Is_Overloadable (Prev) then
1451 Designator := Analyze_Subprogram_Specification (Spec);
1452 Prev := Find_Corresponding_Spec (N);
1455 if No (Prev) or else not Comes_From_Source (Prev) then
1456 Designator := Analyze_Subprogram_Specification (Spec);
1457 Set_Has_Completion (Designator);
1459 -- Signal to caller that this is a procedure declaration
1461 Is_Completion := False;
1463 -- Null procedures are always inlined, but generic formal subprograms
1464 -- which appear as such in the internal instance of formal packages,
1465 -- need no completion and are not marked Inline.
1468 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1470 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1471 Set_Body_To_Inline (N, Null_Body);
1472 Set_Is_Inlined (Designator);
1476 -- The null procedure is a completion. We unconditionally rewrite
1477 -- this as a null body (even if expansion is not active), because
1478 -- there are various error checks that are applied on this body
1479 -- when it is analyzed (e.g. correct aspect placement).
1481 if Has_Completion (Prev) then
1482 Error_Msg_Sloc := Sloc (Prev);
1483 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1486 Is_Completion := True;
1487 Rewrite (N, Null_Body);
1490 end Analyze_Null_Procedure;
1492 -----------------------------
1493 -- Analyze_Operator_Symbol --
1494 -----------------------------
1496 -- An operator symbol such as "+" or "and" may appear in context where the
1497 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1498 -- is just a string, as in (conjunction = "or"). In these cases the parser
1499 -- generates this node, and the semantics does the disambiguation. Other
1500 -- such case are actuals in an instantiation, the generic unit in an
1501 -- instantiation, and pragma arguments.
1503 procedure Analyze_Operator_Symbol (N : Node_Id) is
1504 Par : constant Node_Id := Parent (N);
1507 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1508 or else Nkind (Par) = N_Function_Instantiation
1509 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1510 or else (Nkind (Par) = N_Pragma_Argument_Association
1511 and then not Is_Pragma_String_Literal (Par))
1512 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1513 or else (Nkind (Par) = N_Attribute_Reference
1514 and then Attribute_Name (Par) /= Name_Value)
1516 Find_Direct_Name (N);
1519 Change_Operator_Symbol_To_String_Literal (N);
1522 end Analyze_Operator_Symbol;
1524 -----------------------------------
1525 -- Analyze_Parameter_Association --
1526 -----------------------------------
1528 procedure Analyze_Parameter_Association (N : Node_Id) is
1530 Analyze (Explicit_Actual_Parameter (N));
1531 end Analyze_Parameter_Association;
1533 ----------------------------
1534 -- Analyze_Procedure_Call --
1535 ----------------------------
1537 procedure Analyze_Procedure_Call (N : Node_Id) is
1538 procedure Analyze_Call_And_Resolve;
1539 -- Do Analyze and Resolve calls for procedure call
1540 -- At end, check illegal order dependence.
1542 ------------------------------
1543 -- Analyze_Call_And_Resolve --
1544 ------------------------------
1546 procedure Analyze_Call_And_Resolve is
1548 if Nkind (N) = N_Procedure_Call_Statement then
1550 Resolve (N, Standard_Void_Type);
1554 end Analyze_Call_And_Resolve;
1558 Actuals : constant List_Id := Parameter_Associations (N);
1559 Loc : constant Source_Ptr := Sloc (N);
1560 P : constant Node_Id := Name (N);
1564 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
1566 -- Start of processing for Analyze_Procedure_Call
1569 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1570 -- a procedure call or an entry call. The prefix may denote an access
1571 -- to subprogram type, in which case an implicit dereference applies.
1572 -- If the prefix is an indexed component (without implicit dereference)
1573 -- then the construct denotes a call to a member of an entire family.
1574 -- If the prefix is a simple name, it may still denote a call to a
1575 -- parameterless member of an entry family. Resolution of these various
1576 -- interpretations is delicate.
1578 -- Do not analyze machine code statements to avoid rejecting them in
1581 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1582 Set_Etype (P, Standard_Void_Type);
1587 -- If this is a call of the form Obj.Op, the call may have been analyzed
1588 -- and possibly rewritten into a block, in which case we are done.
1590 if Analyzed (N) then
1594 -- If there is an error analyzing the name (which may have been
1595 -- rewritten if the original call was in prefix notation) then error
1596 -- has been emitted already, mark node and return.
1598 if Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1599 Set_Etype (N, Any_Type);
1603 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1604 -- Set the mode now to ensure that any nodes generated during analysis
1605 -- and expansion are properly marked as Ghost.
1609 -- Otherwise analyze the parameters
1611 if Present (Actuals) then
1612 Actual := First (Actuals);
1614 while Present (Actual) loop
1616 Check_Parameterless_Call (Actual);
1621 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1623 if Nkind (P) = N_Attribute_Reference
1624 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1626 Name_Elab_Subp_Body)
1628 if Present (Actuals) then
1630 ("no parameters allowed for this call", First (Actuals));
1634 Set_Etype (N, Standard_Void_Type);
1637 elsif Is_Entity_Name (P)
1638 and then Is_Record_Type (Etype (Entity (P)))
1639 and then Remote_AST_I_Dereference (P)
1641 Ghost_Mode := Save_Ghost_Mode;
1644 elsif Is_Entity_Name (P)
1645 and then Ekind (Entity (P)) /= E_Entry_Family
1647 if Is_Access_Type (Etype (P))
1648 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1649 and then No (Actuals)
1650 and then Comes_From_Source (N)
1652 Error_Msg_N ("missing explicit dereference in call", N);
1655 Analyze_Call_And_Resolve;
1657 -- If the prefix is the simple name of an entry family, this is a
1658 -- parameterless call from within the task body itself.
1660 elsif Is_Entity_Name (P)
1661 and then Nkind (P) = N_Identifier
1662 and then Ekind (Entity (P)) = E_Entry_Family
1663 and then Present (Actuals)
1664 and then No (Next (First (Actuals)))
1666 -- Can be call to parameterless entry family. What appears to be the
1667 -- sole argument is in fact the entry index. Rewrite prefix of node
1668 -- accordingly. Source representation is unchanged by this
1672 Make_Indexed_Component (Loc,
1674 Make_Selected_Component (Loc,
1675 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1676 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1677 Expressions => Actuals);
1678 Set_Name (N, New_N);
1679 Set_Etype (New_N, Standard_Void_Type);
1680 Set_Parameter_Associations (N, No_List);
1681 Analyze_Call_And_Resolve;
1683 elsif Nkind (P) = N_Explicit_Dereference then
1684 if Ekind (Etype (P)) = E_Subprogram_Type then
1685 Analyze_Call_And_Resolve;
1687 Error_Msg_N ("expect access to procedure in call", P);
1690 -- The name can be a selected component or an indexed component that
1691 -- yields an access to subprogram. Such a prefix is legal if the call
1692 -- has parameter associations.
1694 elsif Is_Access_Type (Etype (P))
1695 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1697 if Present (Actuals) then
1698 Analyze_Call_And_Resolve;
1700 Error_Msg_N ("missing explicit dereference in call ", N);
1703 -- If not an access to subprogram, then the prefix must resolve to the
1704 -- name of an entry, entry family, or protected operation.
1706 -- For the case of a simple entry call, P is a selected component where
1707 -- the prefix is the task and the selector name is the entry. A call to
1708 -- a protected procedure will have the same syntax. If the protected
1709 -- object contains overloaded operations, the entity may appear as a
1710 -- function, the context will select the operation whose type is Void.
1712 elsif Nkind (P) = N_Selected_Component
1713 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1717 Analyze_Call_And_Resolve;
1719 elsif Nkind (P) = N_Selected_Component
1720 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1721 and then Present (Actuals)
1722 and then No (Next (First (Actuals)))
1724 -- Can be call to parameterless entry family. What appears to be the
1725 -- sole argument is in fact the entry index. Rewrite prefix of node
1726 -- accordingly. Source representation is unchanged by this
1730 Make_Indexed_Component (Loc,
1731 Prefix => New_Copy (P),
1732 Expressions => Actuals);
1733 Set_Name (N, New_N);
1734 Set_Etype (New_N, Standard_Void_Type);
1735 Set_Parameter_Associations (N, No_List);
1736 Analyze_Call_And_Resolve;
1738 -- For the case of a reference to an element of an entry family, P is
1739 -- an indexed component whose prefix is a selected component (task and
1740 -- entry family), and whose index is the entry family index.
1742 elsif Nkind (P) = N_Indexed_Component
1743 and then Nkind (Prefix (P)) = N_Selected_Component
1744 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1746 Analyze_Call_And_Resolve;
1748 -- If the prefix is the name of an entry family, it is a call from
1749 -- within the task body itself.
1751 elsif Nkind (P) = N_Indexed_Component
1752 and then Nkind (Prefix (P)) = N_Identifier
1753 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1756 Make_Selected_Component (Loc,
1757 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1758 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1759 Rewrite (Prefix (P), New_N);
1761 Analyze_Call_And_Resolve;
1763 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1764 -- procedure name, so the construct can only be a qualified expression.
1766 elsif Nkind (P) = N_Qualified_Expression
1767 and then Ada_Version >= Ada_2012
1769 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1772 -- Anything else is an error
1775 Error_Msg_N ("invalid procedure or entry call", N);
1778 Ghost_Mode := Save_Ghost_Mode;
1779 end Analyze_Procedure_Call;
1781 ------------------------------
1782 -- Analyze_Return_Statement --
1783 ------------------------------
1785 procedure Analyze_Return_Statement (N : Node_Id) is
1787 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
1788 N_Extended_Return_Statement));
1790 Returns_Object : constant Boolean :=
1791 Nkind (N) = N_Extended_Return_Statement
1793 (Nkind (N) = N_Simple_Return_Statement
1794 and then Present (Expression (N)));
1795 -- True if we're returning something; that is, "return <expression>;"
1796 -- or "return Result : T [:= ...]". False for "return;". Used for error
1797 -- checking: If Returns_Object is True, N should apply to a function
1798 -- body; otherwise N should apply to a procedure body, entry body,
1799 -- accept statement, or extended return statement.
1801 function Find_What_It_Applies_To return Entity_Id;
1802 -- Find the entity representing the innermost enclosing body, accept
1803 -- statement, or extended return statement. If the result is a callable
1804 -- construct or extended return statement, then this will be the value
1805 -- of the Return_Applies_To attribute. Otherwise, the program is
1806 -- illegal. See RM-6.5(4/2).
1808 -----------------------------
1809 -- Find_What_It_Applies_To --
1810 -----------------------------
1812 function Find_What_It_Applies_To return Entity_Id is
1813 Result : Entity_Id := Empty;
1816 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1817 -- and postconditions.
1819 for J in reverse 0 .. Scope_Stack.Last loop
1820 Result := Scope_Stack.Table (J).Entity;
1821 exit when not Ekind_In (Result, E_Block, E_Loop)
1822 and then Chars (Result) /= Name_uPostconditions;
1825 pragma Assert (Present (Result));
1827 end Find_What_It_Applies_To;
1829 -- Local declarations
1831 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1832 Kind : constant Entity_Kind := Ekind (Scope_Id);
1833 Loc : constant Source_Ptr := Sloc (N);
1834 Stm_Entity : constant Entity_Id :=
1836 (E_Return_Statement, Current_Scope, Loc, 'R');
1838 -- Start of processing for Analyze_Return_Statement
1841 Set_Return_Statement_Entity (N, Stm_Entity);
1843 Set_Etype (Stm_Entity, Standard_Void_Type);
1844 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1846 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1847 -- (4/2): an inner return statement will apply to this extended return.
1849 if Nkind (N) = N_Extended_Return_Statement then
1850 Push_Scope (Stm_Entity);
1853 -- Check that pragma No_Return is obeyed. Don't complain about the
1854 -- implicitly-generated return that is placed at the end.
1856 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1857 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1860 -- Warn on any unassigned OUT parameters if in procedure
1862 if Ekind (Scope_Id) = E_Procedure then
1863 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1866 -- Check that functions return objects, and other things do not
1868 if Kind = E_Function or else Kind = E_Generic_Function then
1869 if not Returns_Object then
1870 Error_Msg_N ("missing expression in return from function", N);
1873 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1874 if Returns_Object then
1875 Error_Msg_N ("procedure cannot return value (use function)", N);
1878 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1879 if Returns_Object then
1880 if Is_Protected_Type (Scope (Scope_Id)) then
1881 Error_Msg_N ("entry body cannot return value", N);
1883 Error_Msg_N ("accept statement cannot return value", N);
1887 elsif Kind = E_Return_Statement then
1889 -- We are nested within another return statement, which must be an
1890 -- extended_return_statement.
1892 if Returns_Object then
1893 if Nkind (N) = N_Extended_Return_Statement then
1895 ("extended return statement cannot be nested (use `RETURN;`)",
1898 -- Case of a simple return statement with a value inside extended
1899 -- return statement.
1903 ("return nested in extended return statement cannot return "
1904 & "value (use `RETURN;`)", N);
1909 Error_Msg_N ("illegal context for return statement", N);
1912 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1913 Analyze_Function_Return (N);
1915 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1916 Set_Return_Present (Scope_Id);
1919 if Nkind (N) = N_Extended_Return_Statement then
1923 Kill_Current_Values (Last_Assignment_Only => True);
1924 Check_Unreachable_Code (N);
1926 Analyze_Dimension (N);
1927 end Analyze_Return_Statement;
1929 -------------------------------------
1930 -- Analyze_Simple_Return_Statement --
1931 -------------------------------------
1933 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1935 if Present (Expression (N)) then
1936 Mark_Coextensions (N, Expression (N));
1939 Analyze_Return_Statement (N);
1940 end Analyze_Simple_Return_Statement;
1942 -------------------------
1943 -- Analyze_Return_Type --
1944 -------------------------
1946 procedure Analyze_Return_Type (N : Node_Id) is
1947 Designator : constant Entity_Id := Defining_Entity (N);
1948 Typ : Entity_Id := Empty;
1951 -- Normal case where result definition does not indicate an error
1953 if Result_Definition (N) /= Error then
1954 if Nkind (Result_Definition (N)) = N_Access_Definition then
1955 Check_SPARK_05_Restriction
1956 ("access result is not allowed", Result_Definition (N));
1958 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1961 AD : constant Node_Id :=
1962 Access_To_Subprogram_Definition (Result_Definition (N));
1964 if Present (AD) and then Protected_Present (AD) then
1965 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1967 Typ := Access_Definition (N, Result_Definition (N));
1971 Set_Parent (Typ, Result_Definition (N));
1972 Set_Is_Local_Anonymous_Access (Typ);
1973 Set_Etype (Designator, Typ);
1975 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1977 Null_Exclusion_Static_Checks (N);
1979 -- Subtype_Mark case
1982 Find_Type (Result_Definition (N));
1983 Typ := Entity (Result_Definition (N));
1984 Set_Etype (Designator, Typ);
1986 -- Unconstrained array as result is not allowed in SPARK
1988 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
1989 Check_SPARK_05_Restriction
1990 ("returning an unconstrained array is not allowed",
1991 Result_Definition (N));
1994 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1996 Null_Exclusion_Static_Checks (N);
1998 -- If a null exclusion is imposed on the result type, then create
1999 -- a null-excluding itype (an access subtype) and use it as the
2000 -- function's Etype. Note that the null exclusion checks are done
2001 -- right before this, because they don't get applied to types that
2002 -- do not come from source.
2004 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2005 Set_Etype (Designator,
2006 Create_Null_Excluding_Itype
2009 Scope_Id => Scope (Current_Scope)));
2011 -- The new subtype must be elaborated before use because
2012 -- it is visible outside of the function. However its base
2013 -- type may not be frozen yet, so the reference that will
2014 -- force elaboration must be attached to the freezing of
2017 -- If the return specification appears on a proper body,
2018 -- the subtype will have been created already on the spec.
2020 if Is_Frozen (Typ) then
2021 if Nkind (Parent (N)) = N_Subprogram_Body
2022 and then Nkind (Parent (Parent (N))) = N_Subunit
2026 Build_Itype_Reference (Etype (Designator), Parent (N));
2030 Ensure_Freeze_Node (Typ);
2033 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2035 Set_Itype (IR, Etype (Designator));
2036 Append_Freeze_Actions (Typ, New_List (IR));
2041 Set_Etype (Designator, Typ);
2044 if Ekind (Typ) = E_Incomplete_Type
2045 or else (Is_Class_Wide_Type (Typ)
2046 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2048 -- AI05-0151: Tagged incomplete types are allowed in all formal
2049 -- parts. Untagged incomplete types are not allowed in bodies.
2050 -- As a consequence, limited views cannot appear in a basic
2051 -- declaration that is itself within a body, because there is
2052 -- no point at which the non-limited view will become visible.
2054 if Ada_Version >= Ada_2012 then
2055 if From_Limited_With (Typ) and then In_Package_Body then
2057 ("invalid use of incomplete type&",
2058 Result_Definition (N), Typ);
2060 -- The return type of a subprogram body cannot be of a
2061 -- formal incomplete type.
2063 elsif Is_Generic_Type (Typ)
2064 and then Nkind (Parent (N)) = N_Subprogram_Body
2067 ("return type cannot be a formal incomplete type",
2068 Result_Definition (N));
2070 elsif Is_Class_Wide_Type (Typ)
2071 and then Is_Generic_Type (Root_Type (Typ))
2072 and then Nkind (Parent (N)) = N_Subprogram_Body
2075 ("return type cannot be a formal incomplete type",
2076 Result_Definition (N));
2078 elsif Is_Tagged_Type (Typ) then
2081 -- Use is legal in a thunk generated for an operation
2082 -- inherited from a progenitor.
2084 elsif Is_Thunk (Designator)
2085 and then Present (Non_Limited_View (Typ))
2089 elsif Nkind (Parent (N)) = N_Subprogram_Body
2090 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2094 ("invalid use of untagged incomplete type&",
2098 -- The type must be completed in the current package. This
2099 -- is checked at the end of the package declaration when
2100 -- Taft-amendment types are identified. If the return type
2101 -- is class-wide, there is no required check, the type can
2102 -- be a bona fide TAT.
2104 if Ekind (Scope (Current_Scope)) = E_Package
2105 and then In_Private_Part (Scope (Current_Scope))
2106 and then not Is_Class_Wide_Type (Typ)
2108 Append_Elmt (Designator, Private_Dependents (Typ));
2113 ("invalid use of incomplete type&", Designator, Typ);
2118 -- Case where result definition does indicate an error
2121 Set_Etype (Designator, Any_Type);
2123 end Analyze_Return_Type;
2125 -----------------------------
2126 -- Analyze_Subprogram_Body --
2127 -----------------------------
2129 procedure Analyze_Subprogram_Body (N : Node_Id) is
2130 Loc : constant Source_Ptr := Sloc (N);
2131 Body_Spec : constant Node_Id := Specification (N);
2132 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2135 if Debug_Flag_C then
2136 Write_Str ("==> subprogram body ");
2137 Write_Name (Chars (Body_Id));
2138 Write_Str (" from ");
2139 Write_Location (Loc);
2144 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2146 -- The real work is split out into the helper, so it can do "return;"
2147 -- without skipping the debug output:
2149 Analyze_Subprogram_Body_Helper (N);
2151 if Debug_Flag_C then
2153 Write_Str ("<== subprogram body ");
2154 Write_Name (Chars (Body_Id));
2155 Write_Str (" from ");
2156 Write_Location (Loc);
2159 end Analyze_Subprogram_Body;
2161 ------------------------------------
2162 -- Analyze_Subprogram_Body_Helper --
2163 ------------------------------------
2165 -- This procedure is called for regular subprogram bodies, generic bodies,
2166 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2167 -- specification matters, and is used to create a proper declaration for
2168 -- the subprogram, or to perform conformance checks.
2170 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2171 Body_Spec : Node_Id := Specification (N);
2172 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2173 Loc : constant Source_Ptr := Sloc (N);
2174 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2176 Conformant : Boolean;
2177 Desig_View : Entity_Id := Empty;
2178 Exch_Views : Elist_Id := No_Elist;
2180 Prot_Typ : Entity_Id := Empty;
2181 Spec_Decl : Node_Id := Empty;
2182 Spec_Id : Entity_Id;
2184 Last_Real_Spec_Entity : Entity_Id := Empty;
2185 -- When we analyze a separate spec, the entity chain ends up containing
2186 -- the formals, as well as any itypes generated during analysis of the
2187 -- default expressions for parameters, or the arguments of associated
2188 -- precondition/postcondition pragmas (which are analyzed in the context
2189 -- of the spec since they have visibility on formals).
2191 -- These entities belong with the spec and not the body. However we do
2192 -- the analysis of the body in the context of the spec (again to obtain
2193 -- visibility to the formals), and all the entities generated during
2194 -- this analysis end up also chained to the entity chain of the spec.
2195 -- But they really belong to the body, and there is circuitry to move
2196 -- them from the spec to the body.
2198 -- However, when we do this move, we don't want to move the real spec
2199 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2200 -- variable points to the last real spec entity, so we only move those
2201 -- chained beyond that point. It is initialized to Empty to deal with
2202 -- the case where there is no separate spec.
2204 function Body_Has_Contract return Boolean;
2205 -- Check whether unanalyzed body has an aspect or pragma that may
2206 -- generate a SPARK contract.
2208 function Body_Has_SPARK_Mode_On return Boolean;
2209 -- Check whether SPARK_Mode On applies to the subprogram body, either
2210 -- because it is specified directly on the body, or because it is
2211 -- inherited from the enclosing subprogram or package.
2213 procedure Build_Subprogram_Declaration;
2214 -- Create a matching subprogram declaration for subprogram body N
2216 procedure Check_Anonymous_Return;
2217 -- Ada 2005: if a function returns an access type that denotes a task,
2218 -- or a type that contains tasks, we must create a master entity for
2219 -- the anonymous type, which typically will be used in an allocator
2220 -- in the body of the function.
2222 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2223 -- Look ahead to recognize a pragma that may appear after the body.
2224 -- If there is a previous spec, check that it appears in the same
2225 -- declarative part. If the pragma is Inline_Always, perform inlining
2226 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2227 -- If the body acts as a spec, and inlining is required, we create a
2228 -- subprogram declaration for it, in order to attach the body to inline.
2229 -- If pragma does not appear after the body, check whether there is
2230 -- an inline pragma before any local declarations.
2232 procedure Check_Missing_Return;
2233 -- Checks for a function with a no return statements, and also performs
2234 -- the warning checks implemented by Check_Returns. In formal mode, also
2235 -- verify that a function ends with a RETURN and that a procedure does
2236 -- not contain any RETURN.
2238 function Disambiguate_Spec return Entity_Id;
2239 -- When a primitive is declared between the private view and the full
2240 -- view of a concurrent type which implements an interface, a special
2241 -- mechanism is used to find the corresponding spec of the primitive
2244 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2245 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2246 -- incomplete types coming from a limited context and replace their
2247 -- limited views with the non-limited ones. Return the list of changes
2248 -- to be used to undo the transformation.
2250 function Is_Private_Concurrent_Primitive
2251 (Subp_Id : Entity_Id) return Boolean;
2252 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2253 -- type that implements an interface and has a private view.
2255 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2256 -- Undo the transformation done by Exchange_Limited_Views.
2258 procedure Set_Trivial_Subprogram (N : Node_Id);
2259 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2260 -- subprogram whose body is being analyzed. N is the statement node
2261 -- causing the flag to be set, if the following statement is a return
2262 -- of an entity, we mark the entity as set in source to suppress any
2263 -- warning on the stylized use of function stubs with a dummy return.
2265 procedure Verify_Overriding_Indicator;
2266 -- If there was a previous spec, the entity has been entered in the
2267 -- current scope previously. If the body itself carries an overriding
2268 -- indicator, check that it is consistent with the known status of the
2271 -----------------------
2272 -- Body_Has_Contract --
2273 -----------------------
2275 function Body_Has_Contract return Boolean is
2276 Decls : constant List_Id := Declarations (N);
2280 -- Check for aspects that may generate a contract
2282 if Present (Aspect_Specifications (N)) then
2283 Item := First (Aspect_Specifications (N));
2284 while Present (Item) loop
2285 if Is_Subprogram_Contract_Annotation (Item) then
2293 -- Check for pragmas that may generate a contract
2295 if Present (Decls) then
2296 Item := First (Decls);
2297 while Present (Item) loop
2298 if Nkind (Item) = N_Pragma
2299 and then Is_Subprogram_Contract_Annotation (Item)
2309 end Body_Has_Contract;
2311 ----------------------------
2312 -- Body_Has_SPARK_Mode_On --
2313 ----------------------------
2315 function Body_Has_SPARK_Mode_On return Boolean is
2316 Decls : constant List_Id := Declarations (N);
2320 -- Check for SPARK_Mode aspect
2322 if Present (Aspect_Specifications (N)) then
2323 Item := First (Aspect_Specifications (N));
2324 while Present (Item) loop
2325 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2326 return Get_SPARK_Mode_From_Annotation (Item) = On;
2333 -- Check for SPARK_Mode pragma
2335 if Present (Decls) then
2336 Item := First (Decls);
2337 while Present (Item) loop
2339 -- Pragmas that apply to a subprogram body are usually grouped
2340 -- together. Look for a potential pragma SPARK_Mode among them.
2342 if Nkind (Item) = N_Pragma then
2343 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2344 return Get_SPARK_Mode_From_Annotation (Item) = On;
2347 -- Otherwise the first non-pragma declarative item terminates
2348 -- the region where pragma SPARK_Mode may appear.
2358 -- Otherwise, the applicable SPARK_Mode is inherited from the
2359 -- enclosing subprogram or package.
2361 return SPARK_Mode = On;
2362 end Body_Has_SPARK_Mode_On;
2364 ----------------------------------
2365 -- Build_Subprogram_Declaration --
2366 ----------------------------------
2368 procedure Build_Subprogram_Declaration is
2369 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2370 -- Relocate certain categorization pragmas from the declarative list
2371 -- of subprogram body From and insert them after node To. The pragmas
2375 -- Volatile_Function
2381 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2383 Next_Decl : Node_Id;
2386 pragma Assert (Nkind (From) = N_Subprogram_Body);
2388 -- The destination node must be part of a list, as the pragmas are
2389 -- inserted after it.
2391 pragma Assert (Is_List_Member (To));
2393 -- Inspect the declarations of the subprogram body looking for
2394 -- specific pragmas.
2396 Decl := First (Declarations (N));
2397 while Present (Decl) loop
2398 Next_Decl := Next (Decl);
2400 if Nkind (Decl) = N_Pragma
2401 and then Nam_In (Pragma_Name_Unmapped (Decl),
2404 Name_Volatile_Function)
2407 Insert_After (To, Decl);
2417 Subp_Decl : Node_Id;
2419 -- Start of processing for Build_Subprogram_Declaration
2422 -- Create a matching subprogram spec using the profile of the body.
2423 -- The structure of the tree is identical, but has new entities for
2424 -- the defining unit name and formal parameters.
2427 Make_Subprogram_Declaration (Loc,
2428 Specification => Copy_Subprogram_Spec (Body_Spec));
2429 Set_Comes_From_Source (Subp_Decl, True);
2431 -- Relocate the aspects and relevant pragmas from the subprogram body
2432 -- to the generated spec because it acts as the initial declaration.
2434 Insert_Before (N, Subp_Decl);
2435 Move_Aspects (N, To => Subp_Decl);
2436 Move_Pragmas (N, To => Subp_Decl);
2438 Analyze (Subp_Decl);
2440 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2441 -- the body since the expander may generate calls using that entity.
2442 -- Required to ensure that Expand_Call rewrites calls to this
2443 -- function by calls to the built procedure.
2445 if Modify_Tree_For_C
2446 and then Nkind (Body_Spec) = N_Function_Specification
2448 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2450 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2451 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2452 Corresponding_Procedure
2453 (Defining_Entity (Specification (Subp_Decl))));
2456 -- Analyze any relocated source pragmas or pragmas created for aspect
2459 Decl := Next (Subp_Decl);
2460 while Present (Decl) loop
2462 -- Stop the search for pragmas once the body has been reached as
2463 -- this terminates the region where pragmas may appear.
2468 elsif Nkind (Decl) = N_Pragma then
2475 Spec_Id := Defining_Entity (Subp_Decl);
2476 Set_Corresponding_Spec (N, Spec_Id);
2478 -- Mark the generated spec as a source construct to ensure that all
2479 -- calls to it are properly registered in ALI files for GNATprove.
2481 Set_Comes_From_Source (Spec_Id, True);
2483 -- Ensure that the specs of the subprogram declaration and its body
2484 -- are identical, otherwise they will appear non-conformant due to
2485 -- rewritings in the default values of formal parameters.
2487 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2488 Set_Specification (N, Body_Spec);
2489 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2491 -- Ensure that the generated corresponding spec and original body
2492 -- share the same Ghost and SPARK_Mode attributes.
2494 Set_Is_Checked_Ghost_Entity
2495 (Body_Id, Is_Checked_Ghost_Entity (Spec_Id));
2496 Set_Is_Ignored_Ghost_Entity
2497 (Body_Id, Is_Ignored_Ghost_Entity (Spec_Id));
2499 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
2500 Set_SPARK_Pragma_Inherited
2501 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
2502 end Build_Subprogram_Declaration;
2504 ----------------------------
2505 -- Check_Anonymous_Return --
2506 ----------------------------
2508 procedure Check_Anonymous_Return is
2514 if Present (Spec_Id) then
2520 if Ekind (Scop) = E_Function
2521 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2522 and then not Is_Thunk (Scop)
2524 -- Skip internally built functions which handle the case of
2525 -- a null access (see Expand_Interface_Conversion)
2527 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2528 and then not Comes_From_Source (Parent (Scop)))
2530 and then (Has_Task (Designated_Type (Etype (Scop)))
2532 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2534 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2535 and then Expander_Active
2537 -- Avoid cases with no tasking support
2539 and then RTE_Available (RE_Current_Master)
2540 and then not Restriction_Active (No_Task_Hierarchy)
2543 Make_Object_Declaration (Loc,
2544 Defining_Identifier =>
2545 Make_Defining_Identifier (Loc, Name_uMaster),
2546 Constant_Present => True,
2547 Object_Definition =>
2548 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2550 Make_Explicit_Dereference (Loc,
2551 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2553 if Present (Declarations (N)) then
2554 Prepend (Decl, Declarations (N));
2556 Set_Declarations (N, New_List (Decl));
2559 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2560 Set_Has_Master_Entity (Scop);
2562 -- Now mark the containing scope as a task master
2565 while Nkind (Par) /= N_Compilation_Unit loop
2566 Par := Parent (Par);
2567 pragma Assert (Present (Par));
2569 -- If we fall off the top, we are at the outer level, and
2570 -- the environment task is our effective master, so nothing
2574 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2576 Set_Is_Task_Master (Par, True);
2581 end Check_Anonymous_Return;
2583 -------------------------
2584 -- Check_Inline_Pragma --
2585 -------------------------
2587 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2591 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2592 -- True when N is a pragma Inline or Inline_Always that applies
2593 -- to this subprogram.
2595 -----------------------
2596 -- Is_Inline_Pragma --
2597 -----------------------
2599 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2601 if Nkind (N) = N_Pragma
2603 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2604 or else (Pragma_Name_Unmapped (N) = Name_Inline
2606 (Front_End_Inlining or else Optimization_Level > 0)))
2607 and then Present (Pragma_Argument_Associations (N))
2610 Pragma_Arg : Node_Id :=
2611 Expression (First (Pragma_Argument_Associations (N)));
2613 if Nkind (Pragma_Arg) = N_Selected_Component then
2614 Pragma_Arg := Selector_Name (Pragma_Arg);
2617 return Chars (Pragma_Arg) = Chars (Body_Id);
2623 end Is_Inline_Pragma;
2625 -- Start of processing for Check_Inline_Pragma
2628 if not Expander_Active then
2632 if Is_List_Member (N)
2633 and then Present (Next (N))
2634 and then Is_Inline_Pragma (Next (N))
2638 elsif Nkind (N) /= N_Subprogram_Body_Stub
2639 and then Present (Declarations (N))
2640 and then Is_Inline_Pragma (First (Declarations (N)))
2642 Prag := First (Declarations (N));
2648 if Present (Prag) then
2649 if Present (Spec_Id) then
2650 if Is_List_Member (N)
2651 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2652 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2658 -- Create a subprogram declaration, to make treatment uniform.
2659 -- Make the sloc of the subprogram name that of the entity in
2660 -- the body, so that style checks find identical strings.
2663 Subp : constant Entity_Id :=
2664 Make_Defining_Identifier
2665 (Sloc (Body_Id), Chars (Body_Id));
2666 Decl : constant Node_Id :=
2667 Make_Subprogram_Declaration (Loc,
2669 New_Copy_Tree (Specification (N)));
2672 Set_Defining_Unit_Name (Specification (Decl), Subp);
2674 -- To ensure proper coverage when body is inlined, indicate
2675 -- whether the subprogram comes from source.
2677 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2679 if Present (First_Formal (Body_Id)) then
2680 Plist := Copy_Parameter_List (Body_Id);
2681 Set_Parameter_Specifications
2682 (Specification (Decl), Plist);
2685 -- Move aspects to the new spec
2687 if Has_Aspects (N) then
2688 Move_Aspects (N, To => Decl);
2691 Insert_Before (N, Decl);
2694 Set_Has_Pragma_Inline (Subp);
2696 if Pragma_Name (Prag) = Name_Inline_Always then
2697 Set_Is_Inlined (Subp);
2698 Set_Has_Pragma_Inline_Always (Subp);
2701 -- Prior to copying the subprogram body to create a template
2702 -- for it for subsequent inlining, remove the pragma from
2703 -- the current body so that the copy that will produce the
2704 -- new body will start from a completely unanalyzed tree.
2706 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2707 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2714 end Check_Inline_Pragma;
2716 --------------------------
2717 -- Check_Missing_Return --
2718 --------------------------
2720 procedure Check_Missing_Return is
2722 Missing_Ret : Boolean;
2725 if Nkind (Body_Spec) = N_Function_Specification then
2726 if Present (Spec_Id) then
2732 if Return_Present (Id) then
2733 Check_Returns (HSS, 'F', Missing_Ret);
2736 Set_Has_Missing_Return (Id);
2739 -- Within a premature instantiation of a package with no body, we
2740 -- build completions of the functions therein, with a Raise
2741 -- statement. No point in complaining about a missing return in
2744 elsif Ekind (Id) = E_Function
2745 and then In_Instance
2746 and then Present (Statements (HSS))
2747 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2751 elsif Is_Generic_Subprogram (Id)
2752 or else not Is_Machine_Code_Subprogram (Id)
2754 Error_Msg_N ("missing RETURN statement in function body", N);
2757 -- If procedure with No_Return, check returns
2759 elsif Nkind (Body_Spec) = N_Procedure_Specification
2760 and then Present (Spec_Id)
2761 and then No_Return (Spec_Id)
2763 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2766 -- Special checks in SPARK mode
2768 if Nkind (Body_Spec) = N_Function_Specification then
2770 -- In SPARK mode, last statement of a function should be a return
2773 Stat : constant Node_Id := Last_Source_Statement (HSS);
2776 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2777 N_Extended_Return_Statement)
2779 Check_SPARK_05_Restriction
2780 ("last statement in function should be RETURN", Stat);
2784 -- In SPARK mode, verify that a procedure has no return
2786 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2787 if Present (Spec_Id) then
2793 -- Would be nice to point to return statement here, can we
2794 -- borrow the Check_Returns procedure here ???
2796 if Return_Present (Id) then
2797 Check_SPARK_05_Restriction
2798 ("procedure should not have RETURN", N);
2801 end Check_Missing_Return;
2803 -----------------------
2804 -- Disambiguate_Spec --
2805 -----------------------
2807 function Disambiguate_Spec return Entity_Id is
2808 Priv_Spec : Entity_Id;
2811 procedure Replace_Types (To_Corresponding : Boolean);
2812 -- Depending on the flag, replace the type of formal parameters of
2813 -- Body_Id if it is a concurrent type implementing interfaces with
2814 -- the corresponding record type or the other way around.
2816 procedure Replace_Types (To_Corresponding : Boolean) is
2818 Formal_Typ : Entity_Id;
2821 Formal := First_Formal (Body_Id);
2822 while Present (Formal) loop
2823 Formal_Typ := Etype (Formal);
2825 if Is_Class_Wide_Type (Formal_Typ) then
2826 Formal_Typ := Root_Type (Formal_Typ);
2829 -- From concurrent type to corresponding record
2831 if To_Corresponding then
2832 if Is_Concurrent_Type (Formal_Typ)
2833 and then Present (Corresponding_Record_Type (Formal_Typ))
2836 (Corresponding_Record_Type (Formal_Typ)))
2839 Corresponding_Record_Type (Formal_Typ));
2842 -- From corresponding record to concurrent type
2845 if Is_Concurrent_Record_Type (Formal_Typ)
2846 and then Present (Interfaces (Formal_Typ))
2849 Corresponding_Concurrent_Type (Formal_Typ));
2853 Next_Formal (Formal);
2857 -- Start of processing for Disambiguate_Spec
2860 -- Try to retrieve the specification of the body as is. All error
2861 -- messages are suppressed because the body may not have a spec in
2862 -- its current state.
2864 Spec_N := Find_Corresponding_Spec (N, False);
2866 -- It is possible that this is the body of a primitive declared
2867 -- between a private and a full view of a concurrent type. The
2868 -- controlling parameter of the spec carries the concurrent type,
2869 -- not the corresponding record type as transformed by Analyze_
2870 -- Subprogram_Specification. In such cases, we undo the change
2871 -- made by the analysis of the specification and try to find the
2874 -- Note that wrappers already have their corresponding specs and
2875 -- bodies set during their creation, so if the candidate spec is
2876 -- a wrapper, then we definitely need to swap all types to their
2877 -- original concurrent status.
2880 or else Is_Primitive_Wrapper (Spec_N)
2882 -- Restore all references of corresponding record types to the
2883 -- original concurrent types.
2885 Replace_Types (To_Corresponding => False);
2886 Priv_Spec := Find_Corresponding_Spec (N, False);
2888 -- The current body truly belongs to a primitive declared between
2889 -- a private and a full view. We leave the modified body as is,
2890 -- and return the true spec.
2892 if Present (Priv_Spec)
2893 and then Is_Private_Primitive (Priv_Spec)
2898 -- In case that this is some sort of error, restore the original
2899 -- state of the body.
2901 Replace_Types (To_Corresponding => True);
2905 end Disambiguate_Spec;
2907 ----------------------------
2908 -- Exchange_Limited_Views --
2909 ----------------------------
2911 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
2912 Result : Elist_Id := No_Elist;
2914 procedure Detect_And_Exchange (Id : Entity_Id);
2915 -- Determine whether Id's type denotes an incomplete type associated
2916 -- with a limited with clause and exchange the limited view with the
2917 -- non-limited one when available. Note that the non-limited view
2918 -- may exist because of a with_clause in another unit in the context,
2919 -- but cannot be used because the current view of the enclosing unit
2920 -- is still a limited view.
2922 -------------------------
2923 -- Detect_And_Exchange --
2924 -------------------------
2926 procedure Detect_And_Exchange (Id : Entity_Id) is
2927 Typ : constant Entity_Id := Etype (Id);
2929 if From_Limited_With (Typ)
2930 and then Has_Non_Limited_View (Typ)
2931 and then not From_Limited_With (Scope (Typ))
2934 Result := New_Elmt_List;
2937 Prepend_Elmt (Typ, Result);
2938 Prepend_Elmt (Id, Result);
2939 Set_Etype (Id, Non_Limited_View (Typ));
2941 end Detect_And_Exchange;
2947 -- Start of processing for Exchange_Limited_Views
2950 -- Do not process subprogram bodies as they already use the non-
2951 -- limited view of types.
2953 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
2957 -- Examine all formals and swap views when applicable
2959 Formal := First_Formal (Subp_Id);
2960 while Present (Formal) loop
2961 Detect_And_Exchange (Formal);
2963 Next_Formal (Formal);
2966 -- Process the return type of a function
2968 if Ekind (Subp_Id) = E_Function then
2969 Detect_And_Exchange (Subp_Id);
2973 end Exchange_Limited_Views;
2975 -------------------------------------
2976 -- Is_Private_Concurrent_Primitive --
2977 -------------------------------------
2979 function Is_Private_Concurrent_Primitive
2980 (Subp_Id : Entity_Id) return Boolean
2982 Formal_Typ : Entity_Id;
2985 if Present (First_Formal (Subp_Id)) then
2986 Formal_Typ := Etype (First_Formal (Subp_Id));
2988 if Is_Concurrent_Record_Type (Formal_Typ) then
2989 if Is_Class_Wide_Type (Formal_Typ) then
2990 Formal_Typ := Root_Type (Formal_Typ);
2993 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
2996 -- The type of the first formal is a concurrent tagged type with
3000 Is_Concurrent_Type (Formal_Typ)
3001 and then Is_Tagged_Type (Formal_Typ)
3002 and then Has_Private_Declaration (Formal_Typ);
3006 end Is_Private_Concurrent_Primitive;
3008 ---------------------------
3009 -- Restore_Limited_Views --
3010 ---------------------------
3012 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3013 Elmt : Elmt_Id := First_Elmt (Restore_List);
3017 while Present (Elmt) loop
3020 Set_Etype (Id, Node (Elmt));
3023 end Restore_Limited_Views;
3025 ----------------------------
3026 -- Set_Trivial_Subprogram --
3027 ----------------------------
3029 procedure Set_Trivial_Subprogram (N : Node_Id) is
3030 Nxt : constant Node_Id := Next (N);
3033 Set_Is_Trivial_Subprogram (Body_Id);
3035 if Present (Spec_Id) then
3036 Set_Is_Trivial_Subprogram (Spec_Id);
3040 and then Nkind (Nxt) = N_Simple_Return_Statement
3041 and then No (Next (Nxt))
3042 and then Present (Expression (Nxt))
3043 and then Is_Entity_Name (Expression (Nxt))
3045 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3047 end Set_Trivial_Subprogram;
3049 ---------------------------------
3050 -- Verify_Overriding_Indicator --
3051 ---------------------------------
3053 procedure Verify_Overriding_Indicator is
3055 if Must_Override (Body_Spec) then
3056 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3057 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3061 elsif not Present (Overridden_Operation (Spec_Id)) then
3063 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3065 -- Overriding indicators aren't allowed for protected subprogram
3066 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3067 -- this to a warning if -gnatd.E is enabled.
3069 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3070 Error_Msg_Warn := Error_To_Warning;
3072 ("<<overriding indicator not allowed for protected "
3073 & "subprogram body", Body_Spec);
3076 elsif Must_Not_Override (Body_Spec) then
3077 if Present (Overridden_Operation (Spec_Id)) then
3079 ("subprogram& overrides inherited operation",
3080 Body_Spec, Spec_Id);
3082 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3083 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3086 ("subprogram& overrides predefined operator ",
3087 Body_Spec, Spec_Id);
3089 -- Overriding indicators aren't allowed for protected subprogram
3090 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3091 -- this to a warning if -gnatd.E is enabled.
3093 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3094 Error_Msg_Warn := Error_To_Warning;
3097 ("<<overriding indicator not allowed "
3098 & "for protected subprogram body", Body_Spec);
3100 -- If this is not a primitive operation, then the overriding
3101 -- indicator is altogether illegal.
3103 elsif not Is_Primitive (Spec_Id) then
3105 ("overriding indicator only allowed "
3106 & "if subprogram is primitive", Body_Spec);
3109 -- If checking the style rule and the operation overrides, then
3110 -- issue a warning about a missing overriding_indicator. Protected
3111 -- subprogram bodies are excluded from this style checking, since
3112 -- they aren't primitives (even though their declarations can
3113 -- override) and aren't allowed to have an overriding_indicator.
3116 and then Present (Overridden_Operation (Spec_Id))
3117 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3119 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3120 Style.Missing_Overriding (N, Body_Id);
3123 and then Can_Override_Operator (Spec_Id)
3124 and then not Is_Predefined_File_Name
3125 (Unit_File_Name (Get_Source_Unit (Spec_Id)))
3127 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3128 Style.Missing_Overriding (N, Body_Id);
3130 end Verify_Overriding_Indicator;
3134 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
3136 -- Start of processing for Analyze_Subprogram_Body_Helper
3139 -- A [generic] subprogram body "freezes" the contract of the nearest
3140 -- enclosing package body and all other contracts encountered in the
3141 -- same declarative part up to and excluding the subprogram body:
3143 -- package body Nearest_Enclosing_Package
3144 -- with Refined_State => (State => Constit)
3148 -- procedure Freezes_Enclosing_Package_Body
3149 -- with Refined_Depends => (Input => Constit) ...
3151 -- This ensures that any annotations referenced by the contract of the
3152 -- [generic] subprogram body are available. This form of "freezing" is
3153 -- decoupled from the usual Freeze_xxx mechanism because it must also
3154 -- work in the context of generics where normal freezing is disabled.
3156 -- Only bodies coming from source should cause this type of "freezing".
3157 -- Expression functions that act as bodies and complete an initial
3158 -- declaration must be included in this category, hence the use of
3161 if Comes_From_Source (Original_Node (N)) then
3162 Analyze_Previous_Contracts (N);
3165 -- Generic subprograms are handled separately. They always have a
3166 -- generic specification. Determine whether current scope has a
3167 -- previous declaration.
3169 -- If the subprogram body is defined within an instance of the same
3170 -- name, the instance appears as a package renaming, and will be hidden
3171 -- within the subprogram.
3173 if Present (Prev_Id)
3174 and then not Is_Overloadable (Prev_Id)
3175 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3176 or else Comes_From_Source (Prev_Id))
3178 if Is_Generic_Subprogram (Prev_Id) then
3181 -- A subprogram body is Ghost when it is stand alone and subject
3182 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3183 -- the mode now to ensure that any nodes generated during analysis
3184 -- and expansion are properly marked as Ghost.
3186 Set_Ghost_Mode (N, Spec_Id);
3187 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3188 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3190 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3192 if Nkind (N) = N_Subprogram_Body then
3193 HSS := Handled_Statement_Sequence (N);
3194 Check_Missing_Return;
3197 Ghost_Mode := Save_Ghost_Mode;
3201 -- Previous entity conflicts with subprogram name. Attempting to
3202 -- enter name will post error.
3204 Enter_Name (Body_Id);
3205 Ghost_Mode := Save_Ghost_Mode;
3209 -- Non-generic case, find the subprogram declaration, if one was seen,
3210 -- or enter new overloaded entity in the current scope. If the
3211 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3212 -- part of the context of one of its subunits. No need to redo the
3215 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3216 Ghost_Mode := Save_Ghost_Mode;
3220 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3222 if Nkind (N) = N_Subprogram_Body_Stub
3223 or else No (Corresponding_Spec (N))
3225 if Is_Private_Concurrent_Primitive (Body_Id) then
3226 Spec_Id := Disambiguate_Spec;
3228 -- A subprogram body is Ghost when it is stand alone and
3229 -- subject to pragma Ghost or when the corresponding spec is
3230 -- Ghost. Set the mode now to ensure that any nodes generated
3231 -- during analysis and expansion are properly marked as Ghost.
3233 Set_Ghost_Mode (N, Spec_Id);
3236 Spec_Id := Find_Corresponding_Spec (N);
3238 -- A subprogram body is Ghost when it is stand alone and
3239 -- subject to pragma Ghost or when the corresponding spec is
3240 -- Ghost. Set the mode now to ensure that any nodes generated
3241 -- during analysis and expansion are properly marked as Ghost.
3243 Set_Ghost_Mode (N, Spec_Id);
3245 -- In GNATprove mode, if the body has no previous spec, create
3246 -- one so that the inlining machinery can operate properly.
3247 -- Transfer aspects, if any, to the new spec, so that they
3248 -- are legal and can be processed ahead of the body.
3249 -- We make two copies of the given spec, one for the new
3250 -- declaration, and one for the body.
3252 if No (Spec_Id) and then GNATprove_Mode
3254 -- Inlining does not apply during pre-analysis of code
3256 and then Full_Analysis
3258 -- Inlining only applies to full bodies, not stubs
3260 and then Nkind (N) /= N_Subprogram_Body_Stub
3262 -- Inlining only applies to bodies in the source code, not to
3263 -- those generated by the compiler. In particular, expression
3264 -- functions, whose body is generated by the compiler, are
3265 -- treated specially by GNATprove.
3267 and then Comes_From_Source (Body_Id)
3269 -- This cannot be done for a compilation unit, which is not
3270 -- in a context where we can insert a new spec.
3272 and then Is_List_Member (N)
3274 -- Inlining only applies to subprograms without contracts,
3275 -- as a contract is a sign that GNATprove should perform a
3276 -- modular analysis of the subprogram instead of a contextual
3277 -- analysis at each call site. The same test is performed in
3278 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3279 -- here in another form (because the contract has not been
3280 -- attached to the body) to avoid front-end errors in case
3281 -- pragmas are used instead of aspects, because the
3282 -- corresponding pragmas in the body would not be transferred
3283 -- to the spec, leading to legality errors.
3285 and then not Body_Has_Contract
3286 and then not Inside_A_Generic
3288 Build_Subprogram_Declaration;
3290 -- If this is a function that returns a constrained array, and
3291 -- we are generating SPARK_For_C, create subprogram declaration
3292 -- to simplify subsequent C generation.
3295 and then Modify_Tree_For_C
3296 and then Nkind (Body_Spec) = N_Function_Specification
3297 and then Is_Array_Type (Etype (Body_Id))
3298 and then Is_Constrained (Etype (Body_Id))
3300 Build_Subprogram_Declaration;
3304 -- If this is a duplicate body, no point in analyzing it
3306 if Error_Posted (N) then
3307 Ghost_Mode := Save_Ghost_Mode;
3311 -- A subprogram body should cause freezing of its own declaration,
3312 -- but if there was no previous explicit declaration, then the
3313 -- subprogram will get frozen too late (there may be code within
3314 -- the body that depends on the subprogram having been frozen,
3315 -- such as uses of extra formals), so we force it to be frozen
3316 -- here. Same holds if the body and spec are compilation units.
3317 -- Finally, if the return type is an anonymous access to protected
3318 -- subprogram, it must be frozen before the body because its
3319 -- expansion has generated an equivalent type that is used when
3320 -- elaborating the body.
3322 -- An exception in the case of Ada 2012, AI05-177: The bodies
3323 -- created for expression functions do not freeze.
3326 and then Nkind (Original_Node (N)) /= N_Expression_Function
3328 Freeze_Before (N, Body_Id);
3330 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3331 Freeze_Before (N, Spec_Id);
3333 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3334 Freeze_Before (N, Etype (Body_Id));
3338 Spec_Id := Corresponding_Spec (N);
3340 -- A subprogram body is Ghost when it is stand alone and subject
3341 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3342 -- the mode now to ensure that any nodes generated during analysis
3343 -- and expansion are properly marked as Ghost.
3345 Set_Ghost_Mode (N, Spec_Id);
3349 -- Previously we scanned the body to look for nested subprograms, and
3350 -- rejected an inline directive if nested subprograms were present,
3351 -- because the back-end would generate conflicting symbols for the
3352 -- nested bodies. This is now unnecessary.
3354 -- Look ahead to recognize a pragma Inline that appears after the body
3356 Check_Inline_Pragma (Spec_Id);
3358 -- Deal with special case of a fully private operation in the body of
3359 -- the protected type. We must create a declaration for the subprogram,
3360 -- in order to attach the protected subprogram that will be used in
3361 -- internal calls. We exclude compiler generated bodies from the
3362 -- expander since the issue does not arise for those cases.
3365 and then Comes_From_Source (N)
3366 and then Is_Protected_Type (Current_Scope)
3368 Spec_Id := Build_Private_Protected_Declaration (N);
3371 -- If we are generating C and this is a function returning a constrained
3372 -- array type for which we must create a procedure with an extra out
3373 -- parameter, build and analyze the body now. The procedure declaration
3374 -- has already been created. We reuse the source body of the function,
3375 -- because in an instance it may contain global references that cannot
3376 -- be reanalyzed. The source function itself is not used any further,
3377 -- so we mark it as having a completion. If the subprogram is a stub the
3378 -- transformation is done later, when the proper body is analyzed.
3381 and then Modify_Tree_For_C
3382 and then Present (Spec_Id)
3383 and then Ekind (Spec_Id) = E_Function
3384 and then Nkind (N) /= N_Subprogram_Body_Stub
3385 and then Rewritten_For_C (Spec_Id)
3387 Set_Has_Completion (Spec_Id);
3389 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3392 -- The entity for the created procedure must remain invisible, so it
3393 -- does not participate in resolution of subsequent references to the
3396 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3400 -- If a separate spec is present, then deal with freezing issues
3402 if Present (Spec_Id) then
3403 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3404 Verify_Overriding_Indicator;
3406 -- In general, the spec will be frozen when we start analyzing the
3407 -- body. However, for internally generated operations, such as
3408 -- wrapper functions for inherited operations with controlling
3409 -- results, the spec may not have been frozen by the time we expand
3410 -- the freeze actions that include the bodies. In particular, extra
3411 -- formals for accessibility or for return-in-place may need to be
3412 -- generated. Freeze nodes, if any, are inserted before the current
3413 -- body. These freeze actions are also needed in ASIS mode and in
3414 -- Compile_Only mode to enable the proper back-end type annotations.
3415 -- They are necessary in any case to insure order of elaboration
3418 if not Is_Frozen (Spec_Id)
3419 and then (Expander_Active
3421 or else (Operating_Mode = Check_Semantics
3422 and then Serious_Errors_Detected = 0))
3424 Set_Has_Delayed_Freeze (Spec_Id);
3425 Freeze_Before (N, Spec_Id);
3429 -- Place subprogram on scope stack, and make formals visible. If there
3430 -- is a spec, the visible entity remains that of the spec.
3432 if Present (Spec_Id) then
3433 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3435 if Is_Child_Unit (Spec_Id) then
3436 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3440 Style.Check_Identifier (Body_Id, Spec_Id);
3443 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3444 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3446 if Is_Abstract_Subprogram (Spec_Id) then
3447 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3448 Ghost_Mode := Save_Ghost_Mode;
3452 Set_Convention (Body_Id, Convention (Spec_Id));
3453 Set_Has_Completion (Spec_Id);
3455 -- Inherit the "ghostness" of the subprogram spec. Note that this
3456 -- property is not directly inherited as the body may be subject
3457 -- to a different Ghost assertion policy.
3459 if Ghost_Mode > None or else Is_Ghost_Entity (Spec_Id) then
3460 Set_Is_Ghost_Entity (Body_Id);
3462 -- The Ghost policy in effect at the point of declaration and
3463 -- at the point of completion must match (SPARK RM 6.9(14)).
3465 Check_Ghost_Completion (Spec_Id, Body_Id);
3468 if Is_Protected_Type (Scope (Spec_Id)) then
3469 Prot_Typ := Scope (Spec_Id);
3472 -- If this is a body generated for a renaming, do not check for
3473 -- full conformance. The check is redundant, because the spec of
3474 -- the body is a copy of the spec in the renaming declaration,
3475 -- and the test can lead to spurious errors on nested defaults.
3477 if Present (Spec_Decl)
3478 and then not Comes_From_Source (N)
3480 (Nkind (Original_Node (Spec_Decl)) =
3481 N_Subprogram_Renaming_Declaration
3482 or else (Present (Corresponding_Body (Spec_Decl))
3484 Nkind (Unit_Declaration_Node
3485 (Corresponding_Body (Spec_Decl))) =
3486 N_Subprogram_Renaming_Declaration))
3490 -- Conversely, the spec may have been generated for specless body
3491 -- with an inline pragma. The entity comes from source, which is
3492 -- both semantically correct and necessary for proper inlining.
3493 -- The subprogram declaration itself is not in the source.
3495 elsif Comes_From_Source (N)
3496 and then Present (Spec_Decl)
3497 and then not Comes_From_Source (Spec_Decl)
3498 and then Has_Pragma_Inline (Spec_Id)
3505 Fully_Conformant, True, Conformant, Body_Id);
3508 -- If the body is not fully conformant, we have to decide if we
3509 -- should analyze it or not. If it has a really messed up profile
3510 -- then we probably should not analyze it, since we will get too
3511 -- many bogus messages.
3513 -- Our decision is to go ahead in the non-fully conformant case
3514 -- only if it is at least mode conformant with the spec. Note
3515 -- that the call to Check_Fully_Conformant has issued the proper
3516 -- error messages to complain about the lack of conformance.
3519 and then not Mode_Conformant (Body_Id, Spec_Id)
3521 Ghost_Mode := Save_Ghost_Mode;
3526 if Spec_Id /= Body_Id then
3527 Reference_Body_Formals (Spec_Id, Body_Id);
3530 Set_Ekind (Body_Id, E_Subprogram_Body);
3532 if Nkind (N) = N_Subprogram_Body_Stub then
3533 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3538 Set_Corresponding_Spec (N, Spec_Id);
3540 -- Ada 2005 (AI-345): If the operation is a primitive operation
3541 -- of a concurrent type, the type of the first parameter has been
3542 -- replaced with the corresponding record, which is the proper
3543 -- run-time structure to use. However, within the body there may
3544 -- be uses of the formals that depend on primitive operations
3545 -- of the type (in particular calls in prefixed form) for which
3546 -- we need the original concurrent type. The operation may have
3547 -- several controlling formals, so the replacement must be done
3550 if Comes_From_Source (Spec_Id)
3551 and then Present (First_Entity (Spec_Id))
3552 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3553 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3554 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3555 and then Present (Corresponding_Concurrent_Type
3556 (Etype (First_Entity (Spec_Id))))
3559 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3563 Form := First_Formal (Spec_Id);
3564 while Present (Form) loop
3565 if Etype (Form) = Typ then
3566 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3574 -- Make the formals visible, and place subprogram on scope stack.
3575 -- This is also the point at which we set Last_Real_Spec_Entity
3576 -- to mark the entities which will not be moved to the body.
3578 Install_Formals (Spec_Id);
3579 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3581 -- Within an instance, add local renaming declarations so that
3582 -- gdb can retrieve the values of actuals more easily. This is
3583 -- only relevant if generating code (and indeed we definitely
3584 -- do not want these definitions -gnatc mode, because that would
3587 if Is_Generic_Instance (Spec_Id)
3588 and then Is_Wrapper_Package (Current_Scope)
3589 and then Expander_Active
3591 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3594 Push_Scope (Spec_Id);
3596 -- Make sure that the subprogram is immediately visible. For
3597 -- child units that have no separate spec this is indispensable.
3598 -- Otherwise it is safe albeit redundant.
3600 Set_Is_Immediately_Visible (Spec_Id);
3603 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3604 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3605 Set_Scope (Body_Id, Scope (Spec_Id));
3607 -- Case of subprogram body with no previous spec
3610 -- Check for style warning required
3614 -- Only apply check for source level subprograms for which checks
3615 -- have not been suppressed.
3617 and then Comes_From_Source (Body_Id)
3618 and then not Suppress_Style_Checks (Body_Id)
3620 -- No warnings within an instance
3622 and then not In_Instance
3624 -- No warnings for expression functions
3626 and then Nkind (Original_Node (N)) /= N_Expression_Function
3628 Style.Body_With_No_Spec (N);
3631 New_Overloaded_Entity (Body_Id);
3633 -- A subprogram body declared within a Ghost region is automatically
3634 -- Ghost (SPARK RM 6.9(2)).
3636 if Ghost_Mode > None then
3637 Set_Is_Ghost_Entity (Body_Id);
3640 if Nkind (N) /= N_Subprogram_Body_Stub then
3641 Set_Acts_As_Spec (N);
3642 Generate_Definition (Body_Id);
3644 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3646 -- If the body is an entry wrapper created for an entry with
3647 -- preconditions, it must be compiled in the context of the
3648 -- enclosing synchronized object, because it may mention other
3649 -- operations of the type.
3651 if Is_Entry_Wrapper (Body_Id) then
3653 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3656 Install_Declarations (Prot);
3660 Install_Formals (Body_Id);
3662 Push_Scope (Body_Id);
3665 -- For stubs and bodies with no previous spec, generate references to
3668 Generate_Reference_To_Formals (Body_Id);
3671 -- Entry barrier functions are generated outside the protected type and
3672 -- should not carry the SPARK_Mode of the enclosing context.
3674 if Nkind (N) = N_Subprogram_Body
3675 and then Is_Entry_Barrier_Function (N)
3679 -- The body is generated as part of expression function expansion. When
3680 -- the expression function appears in the visible declarations of a
3681 -- package, the body is added to the private declarations. Since both
3682 -- declarative lists may be subject to a different SPARK_Mode, inherit
3683 -- the mode of the spec.
3685 -- package P with SPARK_Mode is
3686 -- function Expr_Func ... is (...); -- original
3687 -- [function Expr_Func ...;] -- generated spec
3690 -- pragma SPARK_Mode (Off);
3691 -- [function Expr_Func ... is return ...;] -- generated body
3692 -- end P; -- mode is ON
3694 elsif not Comes_From_Source (N)
3695 and then Present (Prev_Id)
3696 and then Is_Expression_Function (Prev_Id)
3698 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Prev_Id));
3699 Set_SPARK_Pragma_Inherited
3700 (Body_Id, SPARK_Pragma_Inherited (Prev_Id));
3702 -- Set the SPARK_Mode from the current context (may be overwritten later
3703 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
3704 -- initially on a stand-alone subprogram body, but is then relocated to
3705 -- a generated corresponding spec. In this scenario the mode is shared
3706 -- between the spec and body.
3708 elsif No (SPARK_Pragma (Body_Id)) then
3709 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
3710 Set_SPARK_Pragma_Inherited (Body_Id);
3713 -- If this is the proper body of a stub, we must verify that the stub
3714 -- conforms to the body, and to the previous spec if one was present.
3715 -- We know already that the body conforms to that spec. This test is
3716 -- only required for subprograms that come from source.
3718 if Nkind (Parent (N)) = N_Subunit
3719 and then Comes_From_Source (N)
3720 and then not Error_Posted (Body_Id)
3721 and then Nkind (Corresponding_Stub (Parent (N))) =
3722 N_Subprogram_Body_Stub
3725 Old_Id : constant Entity_Id :=
3727 (Specification (Corresponding_Stub (Parent (N))));
3729 Conformant : Boolean := False;
3732 if No (Spec_Id) then
3733 Check_Fully_Conformant (Body_Id, Old_Id);
3737 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
3739 if not Conformant then
3741 -- The stub was taken to be a new declaration. Indicate that
3744 Set_Has_Completion (Old_Id, False);
3750 Set_Has_Completion (Body_Id);
3751 Check_Eliminated (Body_Id);
3753 -- Analyze any aspect specifications that appear on the subprogram body
3754 -- stub. Stop the analysis now as the stub does not have a declarative
3755 -- or a statement part, and it cannot be inlined.
3757 if Nkind (N) = N_Subprogram_Body_Stub then
3758 if Has_Aspects (N) then
3759 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
3762 Ghost_Mode := Save_Ghost_Mode;
3768 -- Note: Normally we don't do any inlining if expansion is off, since
3769 -- we won't generate code in any case. An exception arises in GNATprove
3770 -- mode where we want to expand some calls in place, even with expansion
3771 -- disabled, since the inlining eases formal verification.
3773 if not GNATprove_Mode
3774 and then Expander_Active
3775 and then Serious_Errors_Detected = 0
3776 and then Present (Spec_Id)
3777 and then Has_Pragma_Inline (Spec_Id)
3779 -- Legacy implementation (relying on front-end inlining)
3781 if not Back_End_Inlining then
3782 if (Has_Pragma_Inline_Always (Spec_Id)
3783 and then not Opt.Disable_FE_Inline_Always)
3784 or else (Front_End_Inlining
3785 and then not Opt.Disable_FE_Inline)
3787 Build_Body_To_Inline (N, Spec_Id);
3790 -- New implementation (relying on back-end inlining)
3793 if Has_Pragma_Inline_Always (Spec_Id)
3794 or else Optimization_Level > 0
3796 -- Handle function returning an unconstrained type
3798 if Comes_From_Source (Body_Id)
3799 and then Ekind (Spec_Id) = E_Function
3800 and then Returns_Unconstrained_Type (Spec_Id)
3802 -- If function builds in place, i.e. returns a limited type,
3803 -- inlining cannot be done.
3805 and then not Is_Limited_Type (Etype (Spec_Id))
3807 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
3811 Subp_Body : constant Node_Id :=
3812 Unit_Declaration_Node (Body_Id);
3813 Subp_Decl : constant List_Id := Declarations (Subp_Body);
3816 -- Do not pass inlining to the backend if the subprogram
3817 -- has declarations or statements which cannot be inlined
3818 -- by the backend. This check is done here to emit an
3819 -- error instead of the generic warning message reported
3820 -- by the GCC backend (ie. "function might not be
3823 if Present (Subp_Decl)
3824 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
3828 elsif Has_Excluded_Statement
3831 (Handled_Statement_Sequence (Subp_Body)))
3835 -- If the backend inlining is available then at this
3836 -- stage we only have to mark the subprogram as inlined.
3837 -- The expander will take care of registering it in the
3838 -- table of subprograms inlined by the backend a part of
3839 -- processing calls to it (cf. Expand_Call)
3842 Set_Is_Inlined (Spec_Id);
3849 -- In GNATprove mode, inline only when there is a separate subprogram
3850 -- declaration for now, as inlining of subprogram bodies acting as
3851 -- declarations, or subprogram stubs, are not supported by front-end
3852 -- inlining. This inlining should occur after analysis of the body, so
3853 -- that it is known whether the value of SPARK_Mode, which can be
3854 -- defined by a pragma inside the body, is applicable to the body.
3856 elsif GNATprove_Mode
3857 and then Full_Analysis
3858 and then not Inside_A_Generic
3859 and then Present (Spec_Id)
3861 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
3862 and then Body_Has_SPARK_Mode_On
3863 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
3864 and then not Body_Has_Contract
3866 Build_Body_To_Inline (N, Spec_Id);
3869 -- When generating code, inherited pre/postconditions are handled when
3870 -- expanding the corresponding contract.
3872 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
3873 -- of the specification we have to install the private withed units.
3874 -- This holds for child units as well.
3876 if Is_Compilation_Unit (Body_Id)
3877 or else Nkind (Parent (N)) = N_Compilation_Unit
3879 Install_Private_With_Clauses (Body_Id);
3882 Check_Anonymous_Return;
3884 -- Set the Protected_Formal field of each extra formal of the protected
3885 -- subprogram to reference the corresponding extra formal of the
3886 -- subprogram that implements it. For regular formals this occurs when
3887 -- the protected subprogram's declaration is expanded, but the extra
3888 -- formals don't get created until the subprogram is frozen. We need to
3889 -- do this before analyzing the protected subprogram's body so that any
3890 -- references to the original subprogram's extra formals will be changed
3891 -- refer to the implementing subprogram's formals (see Expand_Formal).
3893 if Present (Spec_Id)
3894 and then Is_Protected_Type (Scope (Spec_Id))
3895 and then Present (Protected_Body_Subprogram (Spec_Id))
3898 Impl_Subp : constant Entity_Id :=
3899 Protected_Body_Subprogram (Spec_Id);
3900 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
3901 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
3903 while Present (Prot_Ext_Formal) loop
3904 pragma Assert (Present (Impl_Ext_Formal));
3905 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
3906 Next_Formal_With_Extras (Prot_Ext_Formal);
3907 Next_Formal_With_Extras (Impl_Ext_Formal);
3912 -- Now we can go on to analyze the body
3914 HSS := Handled_Statement_Sequence (N);
3915 Set_Actual_Subtypes (N, Current_Scope);
3917 -- Add a declaration for the Protection object, renaming declarations
3918 -- for discriminals and privals and finally a declaration for the entry
3919 -- family index (if applicable). This form of early expansion is done
3920 -- when the Expander is active because Install_Private_Data_Declarations
3921 -- references entities which were created during regular expansion. The
3922 -- subprogram entity must come from source, and not be an internally
3923 -- generated subprogram.
3926 and then Present (Prot_Typ)
3927 and then Present (Spec_Id)
3928 and then Comes_From_Source (Spec_Id)
3929 and then not Is_Eliminated (Spec_Id)
3931 Install_Private_Data_Declarations
3932 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
3935 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
3936 -- may now appear in parameter and result profiles. Since the analysis
3937 -- of a subprogram body may use the parameter and result profile of the
3938 -- spec, swap any limited views with their non-limited counterpart.
3940 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
3941 Exch_Views := Exchange_Limited_Views (Spec_Id);
3944 -- If the return type is an anonymous access type whose designated type
3945 -- is the limited view of a class-wide type and the non-limited view is
3946 -- available, update the return type accordingly.
3948 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
3954 Rtyp := Etype (Spec_Id);
3956 if Ekind (Rtyp) = E_Anonymous_Access_Type then
3957 Etyp := Directly_Designated_Type (Rtyp);
3959 if Is_Class_Wide_Type (Etyp)
3960 and then From_Limited_With (Etyp)
3963 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
3969 -- Analyze any aspect specifications that appear on the subprogram body
3971 if Has_Aspects (N) then
3972 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
3975 Analyze_Declarations (Declarations (N));
3977 -- Verify that the SPARK_Mode of the body agrees with that of its spec
3979 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
3980 if Present (SPARK_Pragma (Spec_Id)) then
3981 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
3983 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
3985 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
3986 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
3987 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
3989 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
3992 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
3996 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
3997 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
3998 Error_Msg_Sloc := Sloc (Spec_Id);
4000 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4004 -- A subprogram body "freezes" its own contract. Analyze the contract
4005 -- after the declarations of the body have been processed as pragmas
4006 -- are now chained on the contract of the subprogram body.
4008 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4010 -- Check completion, and analyze the statements
4013 Inspect_Deferred_Constant_Completion (Declarations (N));
4016 -- Deal with end of scope processing for the body
4018 Process_End_Label (HSS, 't', Current_Scope);
4021 -- If we are compiling an entry wrapper, remove the enclosing
4022 -- synchronized object from the stack.
4024 if Is_Entry_Wrapper (Body_Id) then
4028 Check_Subprogram_Order (N);
4029 Set_Analyzed (Body_Id);
4031 -- If we have a separate spec, then the analysis of the declarations
4032 -- caused the entities in the body to be chained to the spec id, but
4033 -- we want them chained to the body id. Only the formal parameters
4034 -- end up chained to the spec id in this case.
4036 if Present (Spec_Id) then
4038 -- We must conform to the categorization of our spec
4040 Validate_Categorization_Dependency (N, Spec_Id);
4042 -- And if this is a child unit, the parent units must conform
4044 if Is_Child_Unit (Spec_Id) then
4045 Validate_Categorization_Dependency
4046 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4049 -- Here is where we move entities from the spec to the body
4051 -- Case where there are entities that stay with the spec
4053 if Present (Last_Real_Spec_Entity) then
4055 -- No body entities (happens when the only real spec entities come
4056 -- from precondition and postcondition pragmas).
4058 if No (Last_Entity (Body_Id)) then
4059 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4061 -- Body entities present (formals), so chain stuff past them
4065 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4068 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4069 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4070 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4072 -- Case where there are no spec entities, in this case there can be
4073 -- no body entities either, so just move everything.
4075 -- If the body is generated for an expression function, it may have
4076 -- been preanalyzed already, if 'access was applied to it.
4079 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4080 N_Expression_Function
4082 pragma Assert (No (Last_Entity (Body_Id)));
4086 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4087 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4088 Set_First_Entity (Spec_Id, Empty);
4089 Set_Last_Entity (Spec_Id, Empty);
4093 Check_Missing_Return;
4095 -- Now we are going to check for variables that are never modified in
4096 -- the body of the procedure. But first we deal with a special case
4097 -- where we want to modify this check. If the body of the subprogram
4098 -- starts with a raise statement or its equivalent, or if the body
4099 -- consists entirely of a null statement, then it is pretty obvious that
4100 -- it is OK to not reference the parameters. For example, this might be
4101 -- the following common idiom for a stubbed function: statement of the
4102 -- procedure raises an exception. In particular this deals with the
4103 -- common idiom of a stubbed function, which appears something like:
4105 -- function F (A : Integer) return Some_Type;
4108 -- raise Program_Error;
4112 -- Here the purpose of X is simply to satisfy the annoying requirement
4113 -- in Ada that there be at least one return, and we certainly do not
4114 -- want to go posting warnings on X that it is not initialized. On
4115 -- the other hand, if X is entirely unreferenced that should still
4118 -- What we do is to detect these cases, and if we find them, flag the
4119 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4120 -- suppress unwanted warnings. For the case of the function stub above
4121 -- we have a special test to set X as apparently assigned to suppress
4128 -- Skip initial labels (for one thing this occurs when we are in
4129 -- front-end ZCX mode, but in any case it is irrelevant), and also
4130 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
4132 Stm := First (Statements (HSS));
4133 while Nkind (Stm) = N_Label
4134 or else Nkind (Stm) in N_Push_xxx_Label
4139 -- Do the test on the original statement before expansion
4142 Ostm : constant Node_Id := Original_Node (Stm);
4145 -- If explicit raise statement, turn on flag
4147 if Nkind (Ostm) = N_Raise_Statement then
4148 Set_Trivial_Subprogram (Stm);
4150 -- If null statement, and no following statements, turn on flag
4152 elsif Nkind (Stm) = N_Null_Statement
4153 and then Comes_From_Source (Stm)
4154 and then No (Next (Stm))
4156 Set_Trivial_Subprogram (Stm);
4158 -- Check for explicit call cases which likely raise an exception
4160 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4161 if Is_Entity_Name (Name (Ostm)) then
4163 Ent : constant Entity_Id := Entity (Name (Ostm));
4166 -- If the procedure is marked No_Return, then likely it
4167 -- raises an exception, but in any case it is not coming
4168 -- back here, so turn on the flag.
4171 and then Ekind (Ent) = E_Procedure
4172 and then No_Return (Ent)
4174 Set_Trivial_Subprogram (Stm);
4182 -- Check for variables that are never modified
4188 -- If there is a separate spec, then transfer Never_Set_In_Source
4189 -- flags from out parameters to the corresponding entities in the
4190 -- body. The reason we do that is we want to post error flags on
4191 -- the body entities, not the spec entities.
4193 if Present (Spec_Id) then
4194 E1 := First_Entity (Spec_Id);
4195 while Present (E1) loop
4196 if Ekind (E1) = E_Out_Parameter then
4197 E2 := First_Entity (Body_Id);
4198 while Present (E2) loop
4199 exit when Chars (E1) = Chars (E2);
4203 if Present (E2) then
4204 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4212 -- Check references in body
4214 Check_References (Body_Id);
4217 -- Check for nested subprogram, and mark outer level subprogram if so
4223 if Present (Spec_Id) then
4230 Ent := Enclosing_Subprogram (Ent);
4231 exit when No (Ent) or else Is_Subprogram (Ent);
4234 if Present (Ent) then
4235 Set_Has_Nested_Subprogram (Ent);
4239 -- Restore the limited views in the spec, if any, to let the back end
4240 -- process it without running into circularities.
4242 if Exch_Views /= No_Elist then
4243 Restore_Limited_Views (Exch_Views);
4246 if Present (Desig_View) then
4247 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4250 Ghost_Mode := Save_Ghost_Mode;
4251 end Analyze_Subprogram_Body_Helper;
4253 ------------------------------------
4254 -- Analyze_Subprogram_Declaration --
4255 ------------------------------------
4257 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4258 Scop : constant Entity_Id := Current_Scope;
4259 Designator : Entity_Id;
4261 Is_Completion : Boolean;
4262 -- Indicates whether a null procedure declaration is a completion
4265 -- Null procedures are not allowed in SPARK
4267 if Nkind (Specification (N)) = N_Procedure_Specification
4268 and then Null_Present (Specification (N))
4270 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4272 -- Null procedures are allowed in protected types, following the
4273 -- recent AI12-0147.
4275 if Is_Protected_Type (Current_Scope)
4276 and then Ada_Version < Ada_2012
4278 Error_Msg_N ("protected operation cannot be a null procedure", N);
4281 Analyze_Null_Procedure (N, Is_Completion);
4283 -- The null procedure acts as a body, nothing further is needed
4285 if Is_Completion then
4290 Designator := Analyze_Subprogram_Specification (Specification (N));
4292 -- A reference may already have been generated for the unit name, in
4293 -- which case the following call is redundant. However it is needed for
4294 -- declarations that are the rewriting of an expression function.
4296 Generate_Definition (Designator);
4298 -- Set the SPARK mode from the current context (may be overwritten later
4299 -- with explicit pragma). This is not done for entry barrier functions
4300 -- because they are generated outside the protected type and should not
4301 -- carry the mode of the enclosing context.
4303 if Nkind (N) = N_Subprogram_Declaration
4304 and then Is_Entry_Barrier_Function (N)
4308 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4309 Set_SPARK_Pragma_Inherited (Designator);
4312 -- A subprogram declared within a Ghost region is automatically Ghost
4313 -- (SPARK RM 6.9(2)).
4315 if Ghost_Mode > None then
4316 Set_Is_Ghost_Entity (Designator);
4319 if Debug_Flag_C then
4320 Write_Str ("==> subprogram spec ");
4321 Write_Name (Chars (Designator));
4322 Write_Str (" from ");
4323 Write_Location (Sloc (N));
4328 Validate_RCI_Subprogram_Declaration (N);
4329 New_Overloaded_Entity (Designator);
4330 Check_Delayed_Subprogram (Designator);
4332 -- If the type of the first formal of the current subprogram is a non-
4333 -- generic tagged private type, mark the subprogram as being a private
4334 -- primitive. Ditto if this is a function with controlling result, and
4335 -- the return type is currently private. In both cases, the type of the
4336 -- controlling argument or result must be in the current scope for the
4337 -- operation to be primitive.
4339 if Has_Controlling_Result (Designator)
4340 and then Is_Private_Type (Etype (Designator))
4341 and then Scope (Etype (Designator)) = Current_Scope
4342 and then not Is_Generic_Actual_Type (Etype (Designator))
4344 Set_Is_Private_Primitive (Designator);
4346 elsif Present (First_Formal (Designator)) then
4348 Formal_Typ : constant Entity_Id :=
4349 Etype (First_Formal (Designator));
4351 Set_Is_Private_Primitive (Designator,
4352 Is_Tagged_Type (Formal_Typ)
4353 and then Scope (Formal_Typ) = Current_Scope
4354 and then Is_Private_Type (Formal_Typ)
4355 and then not Is_Generic_Actual_Type (Formal_Typ));
4359 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4362 if Ada_Version >= Ada_2005
4363 and then Comes_From_Source (N)
4364 and then Is_Dispatching_Operation (Designator)
4371 if Has_Controlling_Result (Designator) then
4372 Etyp := Etype (Designator);
4375 E := First_Entity (Designator);
4377 and then Is_Formal (E)
4378 and then not Is_Controlling_Formal (E)
4386 if Is_Access_Type (Etyp) then
4387 Etyp := Directly_Designated_Type (Etyp);
4390 if Is_Interface (Etyp)
4391 and then not Is_Abstract_Subprogram (Designator)
4392 and then not (Ekind (Designator) = E_Procedure
4393 and then Null_Present (Specification (N)))
4395 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4397 -- Specialize error message based on procedures vs. functions,
4398 -- since functions can't be null subprograms.
4400 if Ekind (Designator) = E_Procedure then
4402 ("interface procedure % must be abstract or null", N);
4405 ("interface function % must be abstract", N);
4411 -- What is the following code for, it used to be
4413 -- ??? Set_Suppress_Elaboration_Checks
4414 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4416 -- The following seems equivalent, but a bit dubious
4418 if Elaboration_Checks_Suppressed (Designator) then
4419 Set_Kill_Elaboration_Checks (Designator);
4422 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4423 Set_Categorization_From_Scope (Designator, Scop);
4426 -- For a compilation unit, check for library-unit pragmas
4428 Push_Scope (Designator);
4429 Set_Categorization_From_Pragmas (N);
4430 Validate_Categorization_Dependency (N, Designator);
4434 -- For a compilation unit, set body required. This flag will only be
4435 -- reset if a valid Import or Interface pragma is processed later on.
4437 if Nkind (Parent (N)) = N_Compilation_Unit then
4438 Set_Body_Required (Parent (N), True);
4440 if Ada_Version >= Ada_2005
4441 and then Nkind (Specification (N)) = N_Procedure_Specification
4442 and then Null_Present (Specification (N))
4445 ("null procedure cannot be declared at library level", N);
4449 Generate_Reference_To_Formals (Designator);
4450 Check_Eliminated (Designator);
4452 if Debug_Flag_C then
4454 Write_Str ("<== subprogram spec ");
4455 Write_Name (Chars (Designator));
4456 Write_Str (" from ");
4457 Write_Location (Sloc (N));
4461 if Is_Protected_Type (Current_Scope) then
4463 -- Indicate that this is a protected operation, because it may be
4464 -- used in subsequent declarations within the protected type.
4466 Set_Convention (Designator, Convention_Protected);
4469 List_Inherited_Pre_Post_Aspects (Designator);
4471 if Has_Aspects (N) then
4472 Analyze_Aspect_Specifications (N, Designator);
4474 end Analyze_Subprogram_Declaration;
4476 --------------------------------------
4477 -- Analyze_Subprogram_Specification --
4478 --------------------------------------
4480 -- Reminder: N here really is a subprogram specification (not a subprogram
4481 -- declaration). This procedure is called to analyze the specification in
4482 -- both subprogram bodies and subprogram declarations (specs).
4484 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4485 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4486 -- Determine whether entity E denotes the spec or body of an invariant
4489 ------------------------------------
4490 -- Is_Invariant_Procedure_Or_Body --
4491 ------------------------------------
4493 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4494 Decl : constant Node_Id := Unit_Declaration_Node (E);
4498 if Nkind (Decl) = N_Subprogram_Body then
4499 Spec := Corresponding_Spec (Decl);
4506 and then Ekind (Spec) = E_Procedure
4507 and then (Is_Partial_Invariant_Procedure (Spec)
4508 or else Is_Invariant_Procedure (Spec));
4509 end Is_Invariant_Procedure_Or_Body;
4513 Designator : constant Entity_Id := Defining_Entity (N);
4514 Formals : constant List_Id := Parameter_Specifications (N);
4516 -- Start of processing for Analyze_Subprogram_Specification
4519 -- User-defined operator is not allowed in SPARK, except as a renaming
4521 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4522 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4524 Check_SPARK_05_Restriction
4525 ("user-defined operator is not allowed", N);
4528 -- Proceed with analysis. Do not emit a cross-reference entry if the
4529 -- specification comes from an expression function, because it may be
4530 -- the completion of a previous declaration. It is not, the cross-
4531 -- reference entry will be emitted for the new subprogram declaration.
4533 if Nkind (Parent (N)) /= N_Expression_Function then
4534 Generate_Definition (Designator);
4537 if Nkind (N) = N_Function_Specification then
4538 Set_Ekind (Designator, E_Function);
4539 Set_Mechanism (Designator, Default_Mechanism);
4541 Set_Ekind (Designator, E_Procedure);
4542 Set_Etype (Designator, Standard_Void_Type);
4545 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4546 -- those subprograms which could be inlined in GNATprove mode (because
4547 -- Body_To_Inline is non-Empty) but should not be inlined.
4549 if GNATprove_Mode then
4550 Set_Is_Inlined_Always (Designator);
4553 -- Introduce new scope for analysis of the formals and the return type
4555 Set_Scope (Designator, Current_Scope);
4557 if Present (Formals) then
4558 Push_Scope (Designator);
4559 Process_Formals (Formals, N);
4561 -- Check dimensions in N for formals with default expression
4563 Analyze_Dimension_Formals (N, Formals);
4565 -- Ada 2005 (AI-345): If this is an overriding operation of an
4566 -- inherited interface operation, and the controlling type is
4567 -- a synchronized type, replace the type with its corresponding
4568 -- record, to match the proper signature of an overriding operation.
4569 -- Same processing for an access parameter whose designated type is
4570 -- derived from a synchronized interface.
4572 -- This modification is not done for invariant procedures because
4573 -- the corresponding record may not necessarely be visible when the
4574 -- concurrent type acts as the full view of a private type.
4577 -- type Prot is private with Type_Invariant => ...;
4578 -- procedure ConcInvariant (Obj : Prot);
4580 -- protected type Prot is ...;
4581 -- type Concurrent_Record_Prot is record ...;
4582 -- procedure ConcInvariant (Obj : Prot) is
4584 -- end ConcInvariant;
4587 -- In the example above, both the spec and body of the invariant
4588 -- procedure must utilize the private type as the controlling type.
4590 if Ada_Version >= Ada_2005
4591 and then not Is_Invariant_Procedure_Or_Body (Designator)
4595 Formal_Typ : Entity_Id;
4596 Rec_Typ : Entity_Id;
4597 Desig_Typ : Entity_Id;
4600 Formal := First_Formal (Designator);
4601 while Present (Formal) loop
4602 Formal_Typ := Etype (Formal);
4604 if Is_Concurrent_Type (Formal_Typ)
4605 and then Present (Corresponding_Record_Type (Formal_Typ))
4607 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4609 if Present (Interfaces (Rec_Typ)) then
4610 Set_Etype (Formal, Rec_Typ);
4613 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4614 Desig_Typ := Designated_Type (Formal_Typ);
4616 if Is_Concurrent_Type (Desig_Typ)
4617 and then Present (Corresponding_Record_Type (Desig_Typ))
4619 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4621 if Present (Interfaces (Rec_Typ)) then
4622 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
4627 Next_Formal (Formal);
4634 -- The subprogram scope is pushed and popped around the processing of
4635 -- the return type for consistency with call above to Process_Formals
4636 -- (which itself can call Analyze_Return_Type), and to ensure that any
4637 -- itype created for the return type will be associated with the proper
4640 elsif Nkind (N) = N_Function_Specification then
4641 Push_Scope (Designator);
4642 Analyze_Return_Type (N);
4648 if Nkind (N) = N_Function_Specification then
4650 -- Deal with operator symbol case
4652 if Nkind (Designator) = N_Defining_Operator_Symbol then
4653 Valid_Operator_Definition (Designator);
4656 May_Need_Actuals (Designator);
4658 -- Ada 2005 (AI-251): If the return type is abstract, verify that
4659 -- the subprogram is abstract also. This does not apply to renaming
4660 -- declarations, where abstractness is inherited, and to subprogram
4661 -- bodies generated for stream operations, which become renamings as
4664 -- In case of primitives associated with abstract interface types
4665 -- the check is applied later (see Analyze_Subprogram_Declaration).
4667 if not Nkind_In (Original_Node (Parent (N)),
4668 N_Abstract_Subprogram_Declaration,
4669 N_Formal_Abstract_Subprogram_Declaration,
4670 N_Subprogram_Renaming_Declaration)
4672 if Is_Abstract_Type (Etype (Designator))
4673 and then not Is_Interface (Etype (Designator))
4676 ("function that returns abstract type must be abstract", N);
4678 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
4679 -- access result whose designated type is abstract.
4681 elsif Ada_Version >= Ada_2012
4682 and then Nkind (Result_Definition (N)) = N_Access_Definition
4684 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
4685 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
4688 ("function whose access result designates abstract type "
4689 & "must be abstract", N);
4695 end Analyze_Subprogram_Specification;
4697 -----------------------
4698 -- Check_Conformance --
4699 -----------------------
4701 procedure Check_Conformance
4702 (New_Id : Entity_Id;
4704 Ctype : Conformance_Type;
4706 Conforms : out Boolean;
4707 Err_Loc : Node_Id := Empty;
4708 Get_Inst : Boolean := False;
4709 Skip_Controlling_Formals : Boolean := False)
4711 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
4712 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
4713 -- If Errmsg is True, then processing continues to post an error message
4714 -- for conformance error on given node. Two messages are output. The
4715 -- first message points to the previous declaration with a general "no
4716 -- conformance" message. The second is the detailed reason, supplied as
4717 -- Msg. The parameter N provide information for a possible & insertion
4718 -- in the message, and also provides the location for posting the
4719 -- message in the absence of a specified Err_Loc location.
4721 -----------------------
4722 -- Conformance_Error --
4723 -----------------------
4725 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
4732 if No (Err_Loc) then
4738 Error_Msg_Sloc := Sloc (Old_Id);
4741 when Type_Conformant =>
4742 Error_Msg_N -- CODEFIX
4743 ("not type conformant with declaration#!", Enode);
4745 when Mode_Conformant =>
4746 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
4748 ("not mode conformant with operation inherited#!",
4752 ("not mode conformant with declaration#!", Enode);
4755 when Subtype_Conformant =>
4756 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
4758 ("not subtype conformant with operation inherited#!",
4762 ("not subtype conformant with declaration#!", Enode);
4765 when Fully_Conformant =>
4766 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
4767 Error_Msg_N -- CODEFIX
4768 ("not fully conformant with operation inherited#!",
4771 Error_Msg_N -- CODEFIX
4772 ("not fully conformant with declaration#!", Enode);
4776 Error_Msg_NE (Msg, Enode, N);
4778 end Conformance_Error;
4782 Old_Type : constant Entity_Id := Etype (Old_Id);
4783 New_Type : constant Entity_Id := Etype (New_Id);
4784 Old_Formal : Entity_Id;
4785 New_Formal : Entity_Id;
4786 Access_Types_Match : Boolean;
4787 Old_Formal_Base : Entity_Id;
4788 New_Formal_Base : Entity_Id;
4790 -- Start of processing for Check_Conformance
4795 -- We need a special case for operators, since they don't appear
4798 if Ctype = Type_Conformant then
4799 if Ekind (New_Id) = E_Operator
4800 and then Operator_Matches_Spec (New_Id, Old_Id)
4806 -- If both are functions/operators, check return types conform
4808 if Old_Type /= Standard_Void_Type
4810 New_Type /= Standard_Void_Type
4812 -- If we are checking interface conformance we omit controlling
4813 -- arguments and result, because we are only checking the conformance
4814 -- of the remaining parameters.
4816 if Has_Controlling_Result (Old_Id)
4817 and then Has_Controlling_Result (New_Id)
4818 and then Skip_Controlling_Formals
4822 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
4823 if Ctype >= Subtype_Conformant
4824 and then not Predicates_Match (Old_Type, New_Type)
4827 ("\predicate of return type does not match!", New_Id);
4830 ("\return type does not match!", New_Id);
4836 -- Ada 2005 (AI-231): In case of anonymous access types check the
4837 -- null-exclusion and access-to-constant attributes match.
4839 if Ada_Version >= Ada_2005
4840 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
4842 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
4843 or else Is_Access_Constant (Etype (Old_Type)) /=
4844 Is_Access_Constant (Etype (New_Type)))
4846 Conformance_Error ("\return type does not match!", New_Id);
4850 -- If either is a function/operator and the other isn't, error
4852 elsif Old_Type /= Standard_Void_Type
4853 or else New_Type /= Standard_Void_Type
4855 Conformance_Error ("\functions can only match functions!", New_Id);
4859 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
4860 -- If this is a renaming as body, refine error message to indicate that
4861 -- the conflict is with the original declaration. If the entity is not
4862 -- frozen, the conventions don't have to match, the one of the renamed
4863 -- entity is inherited.
4865 if Ctype >= Subtype_Conformant then
4866 if Convention (Old_Id) /= Convention (New_Id) then
4867 if not Is_Frozen (New_Id) then
4870 elsif Present (Err_Loc)
4871 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
4872 and then Present (Corresponding_Spec (Err_Loc))
4874 Error_Msg_Name_1 := Chars (New_Id);
4876 Name_Ada + Convention_Id'Pos (Convention (New_Id));
4877 Conformance_Error ("\prior declaration for% has convention %!");
4880 Conformance_Error ("\calling conventions do not match!");
4885 elsif Is_Formal_Subprogram (Old_Id)
4886 or else Is_Formal_Subprogram (New_Id)
4888 Conformance_Error ("\formal subprograms not allowed!");
4893 -- Deal with parameters
4895 -- Note: we use the entity information, rather than going directly
4896 -- to the specification in the tree. This is not only simpler, but
4897 -- absolutely necessary for some cases of conformance tests between
4898 -- operators, where the declaration tree simply does not exist.
4900 Old_Formal := First_Formal (Old_Id);
4901 New_Formal := First_Formal (New_Id);
4902 while Present (Old_Formal) and then Present (New_Formal) loop
4903 if Is_Controlling_Formal (Old_Formal)
4904 and then Is_Controlling_Formal (New_Formal)
4905 and then Skip_Controlling_Formals
4907 -- The controlling formals will have different types when
4908 -- comparing an interface operation with its match, but both
4909 -- or neither must be access parameters.
4911 if Is_Access_Type (Etype (Old_Formal))
4913 Is_Access_Type (Etype (New_Formal))
4915 goto Skip_Controlling_Formal;
4918 ("\access parameter does not match!", New_Formal);
4922 -- Ada 2012: Mode conformance also requires that formal parameters
4923 -- be both aliased, or neither.
4925 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
4926 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
4928 ("\aliased parameter mismatch!", New_Formal);
4932 if Ctype = Fully_Conformant then
4934 -- Names must match. Error message is more accurate if we do
4935 -- this before checking that the types of the formals match.
4937 if Chars (Old_Formal) /= Chars (New_Formal) then
4938 Conformance_Error ("\name& does not match!", New_Formal);
4940 -- Set error posted flag on new formal as well to stop
4941 -- junk cascaded messages in some cases.
4943 Set_Error_Posted (New_Formal);
4947 -- Null exclusion must match
4949 if Null_Exclusion_Present (Parent (Old_Formal))
4951 Null_Exclusion_Present (Parent (New_Formal))
4953 -- Only give error if both come from source. This should be
4954 -- investigated some time, since it should not be needed ???
4956 if Comes_From_Source (Old_Formal)
4958 Comes_From_Source (New_Formal)
4961 ("\null exclusion for& does not match", New_Formal);
4963 -- Mark error posted on the new formal to avoid duplicated
4964 -- complaint about types not matching.
4966 Set_Error_Posted (New_Formal);
4971 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
4972 -- case occurs whenever a subprogram is being renamed and one of its
4973 -- parameters imposes a null exclusion. For example:
4975 -- type T is null record;
4976 -- type Acc_T is access T;
4977 -- subtype Acc_T_Sub is Acc_T;
4979 -- procedure P (Obj : not null Acc_T_Sub); -- itype
4980 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
4983 Old_Formal_Base := Etype (Old_Formal);
4984 New_Formal_Base := Etype (New_Formal);
4987 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
4988 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
4991 Access_Types_Match := Ada_Version >= Ada_2005
4993 -- Ensure that this rule is only applied when New_Id is a
4994 -- renaming of Old_Id.
4996 and then Nkind (Parent (Parent (New_Id))) =
4997 N_Subprogram_Renaming_Declaration
4998 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
4999 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5000 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5002 -- Now handle the allowed access-type case
5004 and then Is_Access_Type (Old_Formal_Base)
5005 and then Is_Access_Type (New_Formal_Base)
5007 -- The type kinds must match. The only exception occurs with
5008 -- multiple generics of the form:
5011 -- type F is private; type A is private;
5012 -- type F_Ptr is access F; type A_Ptr is access A;
5013 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5014 -- package F_Pack is ... package A_Pack is
5015 -- package F_Inst is
5016 -- new F_Pack (A, A_Ptr, A_P);
5018 -- When checking for conformance between the parameters of A_P
5019 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5020 -- because the compiler has transformed A_Ptr into a subtype of
5021 -- F_Ptr. We catch this case in the code below.
5023 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5025 (Is_Generic_Type (Old_Formal_Base)
5026 and then Is_Generic_Type (New_Formal_Base)
5027 and then Is_Internal (New_Formal_Base)
5028 and then Etype (Etype (New_Formal_Base)) =
5030 and then Directly_Designated_Type (Old_Formal_Base) =
5031 Directly_Designated_Type (New_Formal_Base)
5032 and then ((Is_Itype (Old_Formal_Base)
5033 and then Can_Never_Be_Null (Old_Formal_Base))
5035 (Is_Itype (New_Formal_Base)
5036 and then Can_Never_Be_Null (New_Formal_Base)));
5038 -- Types must always match. In the visible part of an instance,
5039 -- usual overloading rules for dispatching operations apply, and
5040 -- we check base types (not the actual subtypes).
5042 if In_Instance_Visible_Part
5043 and then Is_Dispatching_Operation (New_Id)
5045 if not Conforming_Types
5046 (T1 => Base_Type (Etype (Old_Formal)),
5047 T2 => Base_Type (Etype (New_Formal)),
5049 Get_Inst => Get_Inst)
5050 and then not Access_Types_Match
5052 Conformance_Error ("\type of & does not match!", New_Formal);
5056 elsif not Conforming_Types
5057 (T1 => Old_Formal_Base,
5058 T2 => New_Formal_Base,
5060 Get_Inst => Get_Inst)
5061 and then not Access_Types_Match
5063 -- Don't give error message if old type is Any_Type. This test
5064 -- avoids some cascaded errors, e.g. in case of a bad spec.
5066 if Errmsg and then Old_Formal_Base = Any_Type then
5069 if Ctype >= Subtype_Conformant
5071 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5074 ("\predicate of & does not match!", New_Formal);
5077 ("\type of & does not match!", New_Formal);
5084 -- For mode conformance, mode must match
5086 if Ctype >= Mode_Conformant then
5087 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5088 if not Ekind_In (New_Id, E_Function, E_Procedure)
5089 or else not Is_Primitive_Wrapper (New_Id)
5091 Conformance_Error ("\mode of & does not match!", New_Formal);
5095 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5097 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5099 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5102 ("\mode of & does not match!", New_Formal);
5109 -- Part of mode conformance for access types is having the same
5110 -- constant modifier.
5112 elsif Access_Types_Match
5113 and then Is_Access_Constant (Old_Formal_Base) /=
5114 Is_Access_Constant (New_Formal_Base)
5117 ("\constant modifier does not match!", New_Formal);
5122 if Ctype >= Subtype_Conformant then
5124 -- Ada 2005 (AI-231): In case of anonymous access types check
5125 -- the null-exclusion and access-to-constant attributes must
5126 -- match. For null exclusion, we test the types rather than the
5127 -- formals themselves, since the attribute is only set reliably
5128 -- on the formals in the Ada 95 case, and we exclude the case
5129 -- where Old_Formal is marked as controlling, to avoid errors
5130 -- when matching completing bodies with dispatching declarations
5131 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5133 if Ada_Version >= Ada_2005
5134 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5135 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5137 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5138 Can_Never_Be_Null (Etype (New_Formal))
5140 not Is_Controlling_Formal (Old_Formal))
5142 Is_Access_Constant (Etype (Old_Formal)) /=
5143 Is_Access_Constant (Etype (New_Formal)))
5145 -- Do not complain if error already posted on New_Formal. This
5146 -- avoids some redundant error messages.
5148 and then not Error_Posted (New_Formal)
5150 -- It is allowed to omit the null-exclusion in case of stream
5151 -- attribute subprograms. We recognize stream subprograms
5152 -- through their TSS-generated suffix.
5155 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5158 if TSS_Name /= TSS_Stream_Read
5159 and then TSS_Name /= TSS_Stream_Write
5160 and then TSS_Name /= TSS_Stream_Input
5161 and then TSS_Name /= TSS_Stream_Output
5163 -- Here we have a definite conformance error. It is worth
5164 -- special casing the error message for the case of a
5165 -- controlling formal (which excludes null).
5167 if Is_Controlling_Formal (New_Formal) then
5168 Error_Msg_Node_2 := Scope (New_Formal);
5170 ("\controlling formal & of & excludes null, "
5171 & "declaration must exclude null as well",
5174 -- Normal case (couldn't we give more detail here???)
5178 ("\type of & does not match!", New_Formal);
5187 -- Full conformance checks
5189 if Ctype = Fully_Conformant then
5191 -- We have checked already that names match
5193 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5195 -- Check default expressions for in parameters
5198 NewD : constant Boolean :=
5199 Present (Default_Value (New_Formal));
5200 OldD : constant Boolean :=
5201 Present (Default_Value (Old_Formal));
5203 if NewD or OldD then
5205 -- The old default value has been analyzed because the
5206 -- current full declaration will have frozen everything
5207 -- before. The new default value has not been analyzed,
5208 -- so analyze it now before we check for conformance.
5211 Push_Scope (New_Id);
5212 Preanalyze_Spec_Expression
5213 (Default_Value (New_Formal), Etype (New_Formal));
5217 if not (NewD and OldD)
5218 or else not Fully_Conformant_Expressions
5219 (Default_Value (Old_Formal),
5220 Default_Value (New_Formal))
5223 ("\default expression for & does not match!",
5232 -- A couple of special checks for Ada 83 mode. These checks are
5233 -- skipped if either entity is an operator in package Standard,
5234 -- or if either old or new instance is not from the source program.
5236 if Ada_Version = Ada_83
5237 and then Sloc (Old_Id) > Standard_Location
5238 and then Sloc (New_Id) > Standard_Location
5239 and then Comes_From_Source (Old_Id)
5240 and then Comes_From_Source (New_Id)
5243 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5244 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5247 -- Explicit IN must be present or absent in both cases. This
5248 -- test is required only in the full conformance case.
5250 if In_Present (Old_Param) /= In_Present (New_Param)
5251 and then Ctype = Fully_Conformant
5254 ("\(Ada 83) IN must appear in both declarations",
5259 -- Grouping (use of comma in param lists) must be the same
5260 -- This is where we catch a misconformance like:
5263 -- A : Integer; B : Integer
5265 -- which are represented identically in the tree except
5266 -- for the setting of the flags More_Ids and Prev_Ids.
5268 if More_Ids (Old_Param) /= More_Ids (New_Param)
5269 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5272 ("\grouping of & does not match!", New_Formal);
5278 -- This label is required when skipping controlling formals
5280 <<Skip_Controlling_Formal>>
5282 Next_Formal (Old_Formal);
5283 Next_Formal (New_Formal);
5286 if Present (Old_Formal) then
5287 Conformance_Error ("\too few parameters!");
5290 elsif Present (New_Formal) then
5291 Conformance_Error ("\too many parameters!", New_Formal);
5294 end Check_Conformance;
5296 -----------------------
5297 -- Check_Conventions --
5298 -----------------------
5300 procedure Check_Conventions (Typ : Entity_Id) is
5301 Ifaces_List : Elist_Id;
5303 procedure Check_Convention (Op : Entity_Id);
5304 -- Verify that the convention of inherited dispatching operation Op is
5305 -- consistent among all subprograms it overrides. In order to minimize
5306 -- the search, Search_From is utilized to designate a specific point in
5307 -- the list rather than iterating over the whole list once more.
5309 ----------------------
5310 -- Check_Convention --
5311 ----------------------
5313 procedure Check_Convention (Op : Entity_Id) is
5314 Op_Conv : constant Convention_Id := Convention (Op);
5315 Iface_Conv : Convention_Id;
5316 Iface_Elmt : Elmt_Id;
5317 Iface_Prim_Elmt : Elmt_Id;
5318 Iface_Prim : Entity_Id;
5321 Iface_Elmt := First_Elmt (Ifaces_List);
5322 while Present (Iface_Elmt) loop
5324 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5325 while Present (Iface_Prim_Elmt) loop
5326 Iface_Prim := Node (Iface_Prim_Elmt);
5327 Iface_Conv := Convention (Iface_Prim);
5329 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5330 and then Iface_Conv /= Op_Conv
5333 ("inconsistent conventions in primitive operations", Typ);
5335 Error_Msg_Name_1 := Chars (Op);
5336 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5337 Error_Msg_Sloc := Sloc (Op);
5339 if Comes_From_Source (Op) or else No (Alias (Op)) then
5340 if not Present (Overridden_Operation (Op)) then
5341 Error_Msg_N ("\\primitive % defined #", Typ);
5344 ("\\overriding operation % with "
5345 & "convention % defined #", Typ);
5348 else pragma Assert (Present (Alias (Op)));
5349 Error_Msg_Sloc := Sloc (Alias (Op));
5350 Error_Msg_N ("\\inherited operation % with "
5351 & "convention % defined #", Typ);
5354 Error_Msg_Name_1 := Chars (Op);
5355 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5356 Error_Msg_Sloc := Sloc (Iface_Prim);
5357 Error_Msg_N ("\\overridden operation % with "
5358 & "convention % defined #", Typ);
5360 -- Avoid cascading errors
5365 Next_Elmt (Iface_Prim_Elmt);
5368 Next_Elmt (Iface_Elmt);
5370 end Check_Convention;
5374 Prim_Op : Entity_Id;
5375 Prim_Op_Elmt : Elmt_Id;
5377 -- Start of processing for Check_Conventions
5380 if not Has_Interfaces (Typ) then
5384 Collect_Interfaces (Typ, Ifaces_List);
5386 -- The algorithm checks every overriding dispatching operation against
5387 -- all the corresponding overridden dispatching operations, detecting
5388 -- differences in conventions.
5390 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5391 while Present (Prim_Op_Elmt) loop
5392 Prim_Op := Node (Prim_Op_Elmt);
5394 -- A small optimization: skip the predefined dispatching operations
5395 -- since they always have the same convention.
5397 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5398 Check_Convention (Prim_Op);
5401 Next_Elmt (Prim_Op_Elmt);
5403 end Check_Conventions;
5405 ------------------------------
5406 -- Check_Delayed_Subprogram --
5407 ------------------------------
5409 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5412 procedure Possible_Freeze (T : Entity_Id);
5413 -- T is the type of either a formal parameter or of the return type.
5414 -- If T is not yet frozen and needs a delayed freeze, then the
5415 -- subprogram itself must be delayed.
5417 ---------------------
5418 -- Possible_Freeze --
5419 ---------------------
5421 procedure Possible_Freeze (T : Entity_Id) is
5423 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5424 Set_Has_Delayed_Freeze (Designator);
5426 elsif Is_Access_Type (T)
5427 and then Has_Delayed_Freeze (Designated_Type (T))
5428 and then not Is_Frozen (Designated_Type (T))
5430 Set_Has_Delayed_Freeze (Designator);
5433 end Possible_Freeze;
5435 -- Start of processing for Check_Delayed_Subprogram
5438 -- All subprograms, including abstract subprograms, may need a freeze
5439 -- node if some formal type or the return type needs one.
5441 Possible_Freeze (Etype (Designator));
5442 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5444 -- Need delayed freeze if any of the formal types themselves need
5445 -- a delayed freeze and are not yet frozen.
5447 F := First_Formal (Designator);
5448 while Present (F) loop
5449 Possible_Freeze (Etype (F));
5450 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5454 -- Mark functions that return by reference. Note that it cannot be
5455 -- done for delayed_freeze subprograms because the underlying
5456 -- returned type may not be known yet (for private types)
5458 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5460 Typ : constant Entity_Id := Etype (Designator);
5461 Utyp : constant Entity_Id := Underlying_Type (Typ);
5463 if Is_Limited_View (Typ) then
5464 Set_Returns_By_Ref (Designator);
5465 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5466 Set_Returns_By_Ref (Designator);
5470 end Check_Delayed_Subprogram;
5472 ------------------------------------
5473 -- Check_Discriminant_Conformance --
5474 ------------------------------------
5476 procedure Check_Discriminant_Conformance
5481 Old_Discr : Entity_Id := First_Discriminant (Prev);
5482 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5483 New_Discr_Id : Entity_Id;
5484 New_Discr_Type : Entity_Id;
5486 procedure Conformance_Error (Msg : String; N : Node_Id);
5487 -- Post error message for conformance error on given node. Two messages
5488 -- are output. The first points to the previous declaration with a
5489 -- general "no conformance" message. The second is the detailed reason,
5490 -- supplied as Msg. The parameter N provide information for a possible
5491 -- & insertion in the message.
5493 -----------------------
5494 -- Conformance_Error --
5495 -----------------------
5497 procedure Conformance_Error (Msg : String; N : Node_Id) is
5499 Error_Msg_Sloc := Sloc (Prev_Loc);
5500 Error_Msg_N -- CODEFIX
5501 ("not fully conformant with declaration#!", N);
5502 Error_Msg_NE (Msg, N, N);
5503 end Conformance_Error;
5505 -- Start of processing for Check_Discriminant_Conformance
5508 while Present (Old_Discr) and then Present (New_Discr) loop
5509 New_Discr_Id := Defining_Identifier (New_Discr);
5511 -- The subtype mark of the discriminant on the full type has not
5512 -- been analyzed so we do it here. For an access discriminant a new
5515 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5517 Access_Definition (N, Discriminant_Type (New_Discr));
5520 Analyze (Discriminant_Type (New_Discr));
5521 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5523 -- Ada 2005: if the discriminant definition carries a null
5524 -- exclusion, create an itype to check properly for consistency
5525 -- with partial declaration.
5527 if Is_Access_Type (New_Discr_Type)
5528 and then Null_Exclusion_Present (New_Discr)
5531 Create_Null_Excluding_Itype
5532 (T => New_Discr_Type,
5533 Related_Nod => New_Discr,
5534 Scope_Id => Current_Scope);
5538 if not Conforming_Types
5539 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5541 Conformance_Error ("type of & does not match!", New_Discr_Id);
5544 -- Treat the new discriminant as an occurrence of the old one,
5545 -- for navigation purposes, and fill in some semantic
5546 -- information, for completeness.
5548 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5549 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5550 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5555 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5556 Conformance_Error ("name & does not match!", New_Discr_Id);
5560 -- Default expressions must match
5563 NewD : constant Boolean :=
5564 Present (Expression (New_Discr));
5565 OldD : constant Boolean :=
5566 Present (Expression (Parent (Old_Discr)));
5569 if NewD or OldD then
5571 -- The old default value has been analyzed and expanded,
5572 -- because the current full declaration will have frozen
5573 -- everything before. The new default values have not been
5574 -- expanded, so expand now to check conformance.
5577 Preanalyze_Spec_Expression
5578 (Expression (New_Discr), New_Discr_Type);
5581 if not (NewD and OldD)
5582 or else not Fully_Conformant_Expressions
5583 (Expression (Parent (Old_Discr)),
5584 Expression (New_Discr))
5588 ("default expression for & does not match!",
5595 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
5597 if Ada_Version = Ada_83 then
5599 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
5602 -- Grouping (use of comma in param lists) must be the same
5603 -- This is where we catch a misconformance like:
5606 -- A : Integer; B : Integer
5608 -- which are represented identically in the tree except
5609 -- for the setting of the flags More_Ids and Prev_Ids.
5611 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
5612 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
5615 ("grouping of & does not match!", New_Discr_Id);
5621 Next_Discriminant (Old_Discr);
5625 if Present (Old_Discr) then
5626 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
5629 elsif Present (New_Discr) then
5631 ("too many discriminants!", Defining_Identifier (New_Discr));
5634 end Check_Discriminant_Conformance;
5636 ----------------------------
5637 -- Check_Fully_Conformant --
5638 ----------------------------
5640 procedure Check_Fully_Conformant
5641 (New_Id : Entity_Id;
5643 Err_Loc : Node_Id := Empty)
5646 pragma Warnings (Off, Result);
5649 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
5650 end Check_Fully_Conformant;
5652 --------------------------
5653 -- Check_Limited_Return --
5654 --------------------------
5656 procedure Check_Limited_Return
5662 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
5663 -- replaced by anonymous access results. This is an incompatibility with
5664 -- Ada 95. Not clear whether this should be enforced yet or perhaps
5665 -- controllable with special switch. ???
5667 -- A limited interface that is not immutably limited is OK
5669 if Is_Limited_Interface (R_Type)
5671 not (Is_Task_Interface (R_Type)
5672 or else Is_Protected_Interface (R_Type)
5673 or else Is_Synchronized_Interface (R_Type))
5677 elsif Is_Limited_Type (R_Type)
5678 and then not Is_Interface (R_Type)
5679 and then Comes_From_Source (N)
5680 and then not In_Instance_Body
5681 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
5683 -- Error in Ada 2005
5685 if Ada_Version >= Ada_2005
5686 and then not Debug_Flag_Dot_L
5687 and then not GNAT_Mode
5690 ("(Ada 2005) cannot copy object of a limited type "
5691 & "(RM-2005 6.5(5.5/2))", Expr);
5693 if Is_Limited_View (R_Type) then
5695 ("\return by reference not permitted in Ada 2005", Expr);
5698 -- Warn in Ada 95 mode, to give folks a heads up about this
5701 -- In GNAT mode, this is just a warning, to allow it to be evilly
5702 -- turned off. Otherwise it is a real error.
5704 -- In a generic context, simplify the warning because it makes no
5705 -- sense to discuss pass-by-reference or copy.
5707 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
5708 if Inside_A_Generic then
5710 ("return of limited object not permitted in Ada 2005 "
5711 & "(RM-2005 6.5(5.5/2))?y?", Expr);
5713 elsif Is_Limited_View (R_Type) then
5715 ("return by reference not permitted in Ada 2005 "
5716 & "(RM-2005 6.5(5.5/2))?y?", Expr);
5719 ("cannot copy object of a limited type in Ada 2005 "
5720 & "(RM-2005 6.5(5.5/2))?y?", Expr);
5723 -- Ada 95 mode, compatibility warnings disabled
5726 return; -- skip continuation messages below
5729 if not Inside_A_Generic then
5731 ("\consider switching to return of access type", Expr);
5732 Explain_Limited_Type (R_Type, Expr);
5735 end Check_Limited_Return;
5737 ---------------------------
5738 -- Check_Mode_Conformant --
5739 ---------------------------
5741 procedure Check_Mode_Conformant
5742 (New_Id : Entity_Id;
5744 Err_Loc : Node_Id := Empty;
5745 Get_Inst : Boolean := False)
5748 pragma Warnings (Off, Result);
5751 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
5752 end Check_Mode_Conformant;
5754 --------------------------------
5755 -- Check_Overriding_Indicator --
5756 --------------------------------
5758 procedure Check_Overriding_Indicator
5760 Overridden_Subp : Entity_Id;
5761 Is_Primitive : Boolean)
5767 -- No overriding indicator for literals
5769 if Ekind (Subp) = E_Enumeration_Literal then
5772 elsif Ekind (Subp) = E_Entry then
5773 Decl := Parent (Subp);
5775 -- No point in analyzing a malformed operator
5777 elsif Nkind (Subp) = N_Defining_Operator_Symbol
5778 and then Error_Posted (Subp)
5783 Decl := Unit_Declaration_Node (Subp);
5786 if Nkind_In (Decl, N_Subprogram_Body,
5787 N_Subprogram_Body_Stub,
5788 N_Subprogram_Declaration,
5789 N_Abstract_Subprogram_Declaration,
5790 N_Subprogram_Renaming_Declaration)
5792 Spec := Specification (Decl);
5794 elsif Nkind (Decl) = N_Entry_Declaration then
5801 -- The overriding operation is type conformant with the overridden one,
5802 -- but the names of the formals are not required to match. If the names
5803 -- appear permuted in the overriding operation, this is a possible
5804 -- source of confusion that is worth diagnosing. Controlling formals
5805 -- often carry names that reflect the type, and it is not worthwhile
5806 -- requiring that their names match.
5808 if Present (Overridden_Subp)
5809 and then Nkind (Subp) /= N_Defining_Operator_Symbol
5816 Form1 := First_Formal (Subp);
5817 Form2 := First_Formal (Overridden_Subp);
5819 -- If the overriding operation is a synchronized operation, skip
5820 -- the first parameter of the overridden operation, which is
5821 -- implicit in the new one. If the operation is declared in the
5822 -- body it is not primitive and all formals must match.
5824 if Is_Concurrent_Type (Scope (Subp))
5825 and then Is_Tagged_Type (Scope (Subp))
5826 and then not Has_Completion (Scope (Subp))
5828 Form2 := Next_Formal (Form2);
5831 if Present (Form1) then
5832 Form1 := Next_Formal (Form1);
5833 Form2 := Next_Formal (Form2);
5836 while Present (Form1) loop
5837 if not Is_Controlling_Formal (Form1)
5838 and then Present (Next_Formal (Form2))
5839 and then Chars (Form1) = Chars (Next_Formal (Form2))
5841 Error_Msg_Node_2 := Alias (Overridden_Subp);
5842 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
5844 ("& does not match corresponding formal of&#",
5849 Next_Formal (Form1);
5850 Next_Formal (Form2);
5855 -- If there is an overridden subprogram, then check that there is no
5856 -- "not overriding" indicator, and mark the subprogram as overriding.
5857 -- This is not done if the overridden subprogram is marked as hidden,
5858 -- which can occur for the case of inherited controlled operations
5859 -- (see Derive_Subprogram), unless the inherited subprogram's parent
5860 -- subprogram is not itself hidden. (Note: This condition could probably
5861 -- be simplified, leaving out the testing for the specific controlled
5862 -- cases, but it seems safer and clearer this way, and echoes similar
5863 -- special-case tests of this kind in other places.)
5865 if Present (Overridden_Subp)
5866 and then (not Is_Hidden (Overridden_Subp)
5868 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
5871 and then Present (Alias (Overridden_Subp))
5872 and then not Is_Hidden (Alias (Overridden_Subp))))
5874 if Must_Not_Override (Spec) then
5875 Error_Msg_Sloc := Sloc (Overridden_Subp);
5877 if Ekind (Subp) = E_Entry then
5879 ("entry & overrides inherited operation #", Spec, Subp);
5882 ("subprogram & overrides inherited operation #", Spec, Subp);
5885 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
5886 -- as an extension of Root_Controlled, and thus has a useless Adjust
5887 -- operation. This operation should not be inherited by other limited
5888 -- controlled types. An explicit Adjust for them is not overriding.
5890 elsif Must_Override (Spec)
5891 and then Chars (Overridden_Subp) = Name_Adjust
5892 and then Is_Limited_Type (Etype (First_Formal (Subp)))
5893 and then Present (Alias (Overridden_Subp))
5895 Is_Predefined_File_Name
5896 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))))
5898 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5900 elsif Is_Subprogram (Subp) then
5901 if Is_Init_Proc (Subp) then
5904 elsif No (Overridden_Operation (Subp)) then
5906 -- For entities generated by Derive_Subprograms the overridden
5907 -- operation is the inherited primitive (which is available
5908 -- through the attribute alias)
5910 if (Is_Dispatching_Operation (Subp)
5911 or else Is_Dispatching_Operation (Overridden_Subp))
5912 and then not Comes_From_Source (Overridden_Subp)
5913 and then Find_Dispatching_Type (Overridden_Subp) =
5914 Find_Dispatching_Type (Subp)
5915 and then Present (Alias (Overridden_Subp))
5916 and then Comes_From_Source (Alias (Overridden_Subp))
5918 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
5919 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
5922 Set_Overridden_Operation (Subp, Overridden_Subp);
5923 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
5928 -- If primitive flag is set or this is a protected operation, then
5929 -- the operation is overriding at the point of its declaration, so
5930 -- warn if necessary. Otherwise it may have been declared before the
5931 -- operation it overrides and no check is required.
5934 and then not Must_Override (Spec)
5935 and then (Is_Primitive
5936 or else Ekind (Scope (Subp)) = E_Protected_Type)
5938 Style.Missing_Overriding (Decl, Subp);
5941 -- If Subp is an operator, it may override a predefined operation, if
5942 -- it is defined in the same scope as the type to which it applies.
5943 -- In that case Overridden_Subp is empty because of our implicit
5944 -- representation for predefined operators. We have to check whether the
5945 -- signature of Subp matches that of a predefined operator. Note that
5946 -- first argument provides the name of the operator, and the second
5947 -- argument the signature that may match that of a standard operation.
5948 -- If the indicator is overriding, then the operator must match a
5949 -- predefined signature, because we know already that there is no
5950 -- explicit overridden operation.
5952 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
5953 if Must_Not_Override (Spec) then
5955 -- If this is not a primitive or a protected subprogram, then
5956 -- "not overriding" is illegal.
5959 and then Ekind (Scope (Subp)) /= E_Protected_Type
5961 Error_Msg_N ("overriding indicator only allowed "
5962 & "if subprogram is primitive", Subp);
5964 elsif Can_Override_Operator (Subp) then
5966 ("subprogram& overrides predefined operator ", Spec, Subp);
5969 elsif Must_Override (Spec) then
5970 if No (Overridden_Operation (Subp))
5971 and then not Can_Override_Operator (Subp)
5973 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5976 elsif not Error_Posted (Subp)
5977 and then Style_Check
5978 and then Can_Override_Operator (Subp)
5980 not Is_Predefined_File_Name
5981 (Unit_File_Name (Get_Source_Unit (Subp)))
5983 -- If style checks are enabled, indicate that the indicator is
5984 -- missing. However, at the point of declaration, the type of
5985 -- which this is a primitive operation may be private, in which
5986 -- case the indicator would be premature.
5988 if Has_Private_Declaration (Etype (Subp))
5989 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
5993 Style.Missing_Overriding (Decl, Subp);
5997 elsif Must_Override (Spec) then
5998 if Ekind (Subp) = E_Entry then
5999 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6001 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6004 -- If the operation is marked "not overriding" and it's not primitive
6005 -- then an error is issued, unless this is an operation of a task or
6006 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6007 -- has been specified have already been checked above.
6009 elsif Must_Not_Override (Spec)
6010 and then not Is_Primitive
6011 and then Ekind (Subp) /= E_Entry
6012 and then Ekind (Scope (Subp)) /= E_Protected_Type
6015 ("overriding indicator only allowed if subprogram is primitive",
6019 end Check_Overriding_Indicator;
6025 -- Note: this procedure needs to know far too much about how the expander
6026 -- messes with exceptions. The use of the flag Exception_Junk and the
6027 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6028 -- works, but is not very clean. It would be better if the expansion
6029 -- routines would leave Original_Node working nicely, and we could use
6030 -- Original_Node here to ignore all the peculiar expander messing ???
6032 procedure Check_Returns
6036 Proc : Entity_Id := Empty)
6040 procedure Check_Statement_Sequence (L : List_Id);
6041 -- Internal recursive procedure to check a list of statements for proper
6042 -- termination by a return statement (or a transfer of control or a
6043 -- compound statement that is itself internally properly terminated).
6045 ------------------------------
6046 -- Check_Statement_Sequence --
6047 ------------------------------
6049 procedure Check_Statement_Sequence (L : List_Id) is
6054 function Assert_False return Boolean;
6055 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6056 -- rewritten as a null statement when assertions are off. The assert
6057 -- is not active, but it is still enough to kill the warning.
6063 function Assert_False return Boolean is
6064 Orig : constant Node_Id := Original_Node (Last_Stm);
6067 if Nkind (Orig) = N_Pragma
6068 and then Pragma_Name (Orig) = Name_Assert
6069 and then not Error_Posted (Orig)
6072 Arg : constant Node_Id :=
6073 First (Pragma_Argument_Associations (Orig));
6074 Exp : constant Node_Id := Expression (Arg);
6076 return Nkind (Exp) = N_Identifier
6077 and then Chars (Exp) = Name_False;
6087 Raise_Exception_Call : Boolean;
6088 -- Set True if statement sequence terminated by Raise_Exception call
6089 -- or a Reraise_Occurrence call.
6091 -- Start of processing for Check_Statement_Sequence
6094 Raise_Exception_Call := False;
6096 -- Get last real statement
6098 Last_Stm := Last (L);
6100 -- Deal with digging out exception handler statement sequences that
6101 -- have been transformed by the local raise to goto optimization.
6102 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6103 -- optimization has occurred, we are looking at something like:
6106 -- original stmts in block
6110 -- goto L1; | omitted if No_Exception_Propagation
6115 -- goto L3; -- skip handler when exception not raised
6117 -- <<L1>> -- target label for local exception
6131 -- and what we have to do is to dig out the estmts1 and estmts2
6132 -- sequences (which were the original sequences of statements in
6133 -- the exception handlers) and check them.
6135 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6140 exit when Nkind (Stm) /= N_Block_Statement;
6141 exit when not Exception_Junk (Stm);
6144 exit when Nkind (Stm) /= N_Label;
6145 exit when not Exception_Junk (Stm);
6146 Check_Statement_Sequence
6147 (Statements (Handled_Statement_Sequence (Next (Stm))));
6152 exit when Nkind (Stm) /= N_Goto_Statement;
6153 exit when not Exception_Junk (Stm);
6157 -- Don't count pragmas
6159 while Nkind (Last_Stm) = N_Pragma
6161 -- Don't count call to SS_Release (can happen after Raise_Exception)
6164 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6166 Nkind (Name (Last_Stm)) = N_Identifier
6168 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6170 -- Don't count exception junk
6173 (Nkind_In (Last_Stm, N_Goto_Statement,
6175 N_Object_Declaration)
6176 and then Exception_Junk (Last_Stm))
6177 or else Nkind (Last_Stm) in N_Push_xxx_Label
6178 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6180 -- Inserted code, such as finalization calls, is irrelevant: we only
6181 -- need to check original source.
6183 or else Is_Rewrite_Insertion (Last_Stm)
6188 -- Here we have the "real" last statement
6190 Kind := Nkind (Last_Stm);
6192 -- Transfer of control, OK. Note that in the No_Return procedure
6193 -- case, we already diagnosed any explicit return statements, so
6194 -- we can treat them as OK in this context.
6196 if Is_Transfer (Last_Stm) then
6199 -- Check cases of explicit non-indirect procedure calls
6201 elsif Kind = N_Procedure_Call_Statement
6202 and then Is_Entity_Name (Name (Last_Stm))
6204 -- Check call to Raise_Exception procedure which is treated
6205 -- specially, as is a call to Reraise_Occurrence.
6207 -- We suppress the warning in these cases since it is likely that
6208 -- the programmer really does not expect to deal with the case
6209 -- of Null_Occurrence, and thus would find a warning about a
6210 -- missing return curious, and raising Program_Error does not
6211 -- seem such a bad behavior if this does occur.
6213 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6214 -- behavior will be to raise Constraint_Error (see AI-329).
6216 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6218 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6220 Raise_Exception_Call := True;
6222 -- For Raise_Exception call, test first argument, if it is
6223 -- an attribute reference for a 'Identity call, then we know
6224 -- that the call cannot possibly return.
6227 Arg : constant Node_Id :=
6228 Original_Node (First_Actual (Last_Stm));
6230 if Nkind (Arg) = N_Attribute_Reference
6231 and then Attribute_Name (Arg) = Name_Identity
6238 -- If statement, need to look inside if there is an else and check
6239 -- each constituent statement sequence for proper termination.
6241 elsif Kind = N_If_Statement
6242 and then Present (Else_Statements (Last_Stm))
6244 Check_Statement_Sequence (Then_Statements (Last_Stm));
6245 Check_Statement_Sequence (Else_Statements (Last_Stm));
6247 if Present (Elsif_Parts (Last_Stm)) then
6249 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6252 while Present (Elsif_Part) loop
6253 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6261 -- Case statement, check each case for proper termination
6263 elsif Kind = N_Case_Statement then
6267 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6268 while Present (Case_Alt) loop
6269 Check_Statement_Sequence (Statements (Case_Alt));
6270 Next_Non_Pragma (Case_Alt);
6276 -- Block statement, check its handled sequence of statements
6278 elsif Kind = N_Block_Statement then
6284 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6293 -- Loop statement. If there is an iteration scheme, we can definitely
6294 -- fall out of the loop. Similarly if there is an exit statement, we
6295 -- can fall out. In either case we need a following return.
6297 elsif Kind = N_Loop_Statement then
6298 if Present (Iteration_Scheme (Last_Stm))
6299 or else Has_Exit (Entity (Identifier (Last_Stm)))
6303 -- A loop with no exit statement or iteration scheme is either
6304 -- an infinite loop, or it has some other exit (raise/return).
6305 -- In either case, no warning is required.
6311 -- Timed entry call, check entry call and delay alternatives
6313 -- Note: in expanded code, the timed entry call has been converted
6314 -- to a set of expanded statements on which the check will work
6315 -- correctly in any case.
6317 elsif Kind = N_Timed_Entry_Call then
6319 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6320 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6323 -- If statement sequence of entry call alternative is missing,
6324 -- then we can definitely fall through, and we post the error
6325 -- message on the entry call alternative itself.
6327 if No (Statements (ECA)) then
6330 -- If statement sequence of delay alternative is missing, then
6331 -- we can definitely fall through, and we post the error
6332 -- message on the delay alternative itself.
6334 -- Note: if both ECA and DCA are missing the return, then we
6335 -- post only one message, should be enough to fix the bugs.
6336 -- If not we will get a message next time on the DCA when the
6339 elsif No (Statements (DCA)) then
6342 -- Else check both statement sequences
6345 Check_Statement_Sequence (Statements (ECA));
6346 Check_Statement_Sequence (Statements (DCA));
6351 -- Conditional entry call, check entry call and else part
6353 -- Note: in expanded code, the conditional entry call has been
6354 -- converted to a set of expanded statements on which the check
6355 -- will work correctly in any case.
6357 elsif Kind = N_Conditional_Entry_Call then
6359 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6362 -- If statement sequence of entry call alternative is missing,
6363 -- then we can definitely fall through, and we post the error
6364 -- message on the entry call alternative itself.
6366 if No (Statements (ECA)) then
6369 -- Else check statement sequence and else part
6372 Check_Statement_Sequence (Statements (ECA));
6373 Check_Statement_Sequence (Else_Statements (Last_Stm));
6379 -- If we fall through, issue appropriate message
6383 -- Kill warning if last statement is a raise exception call,
6384 -- or a pragma Assert (False). Note that with assertions enabled,
6385 -- such a pragma has been converted into a raise exception call
6386 -- already, so the Assert_False is for the assertions off case.
6388 if not Raise_Exception_Call and then not Assert_False then
6390 -- In GNATprove mode, it is an error to have a missing return
6392 Error_Msg_Warn := SPARK_Mode /= On;
6394 -- Issue error message or warning
6397 ("RETURN statement missing following this statement<<!",
6400 ("\Program_Error ]<<!", Last_Stm);
6403 -- Note: we set Err even though we have not issued a warning
6404 -- because we still have a case of a missing return. This is
6405 -- an extremely marginal case, probably will never be noticed
6406 -- but we might as well get it right.
6410 -- Otherwise we have the case of a procedure marked No_Return
6413 if not Raise_Exception_Call then
6414 if GNATprove_Mode then
6416 ("implied return after this statement "
6417 & "would have raised Program_Error", Last_Stm);
6420 ("implied return after this statement "
6421 & "will raise Program_Error??", Last_Stm);
6424 Error_Msg_Warn := SPARK_Mode /= On;
6426 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6430 RE : constant Node_Id :=
6431 Make_Raise_Program_Error (Sloc (Last_Stm),
6432 Reason => PE_Implicit_Return);
6434 Insert_After (Last_Stm, RE);
6438 end Check_Statement_Sequence;
6440 -- Start of processing for Check_Returns
6444 Check_Statement_Sequence (Statements (HSS));
6446 if Present (Exception_Handlers (HSS)) then
6447 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6448 while Present (Handler) loop
6449 Check_Statement_Sequence (Statements (Handler));
6450 Next_Non_Pragma (Handler);
6455 ----------------------------
6456 -- Check_Subprogram_Order --
6457 ----------------------------
6459 procedure Check_Subprogram_Order (N : Node_Id) is
6461 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6462 -- This is used to check if S1 > S2 in the sense required by this test,
6463 -- for example nameab < namec, but name2 < name10.
6465 -----------------------------
6466 -- Subprogram_Name_Greater --
6467 -----------------------------
6469 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6474 -- Deal with special case where names are identical except for a
6475 -- numerical suffix. These are handled specially, taking the numeric
6476 -- ordering from the suffix into account.
6479 while S1 (L1) in '0' .. '9' loop
6484 while S2 (L2) in '0' .. '9' loop
6488 -- If non-numeric parts non-equal, do straight compare
6490 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6493 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6494 -- that a missing suffix is treated as numeric zero in this test.
6498 while L1 < S1'Last loop
6500 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6504 while L2 < S2'Last loop
6506 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6511 end Subprogram_Name_Greater;
6513 -- Start of processing for Check_Subprogram_Order
6516 -- Check body in alpha order if this is option
6519 and then Style_Check_Order_Subprograms
6520 and then Nkind (N) = N_Subprogram_Body
6521 and then Comes_From_Source (N)
6522 and then In_Extended_Main_Source_Unit (N)
6526 renames Scope_Stack.Table
6527 (Scope_Stack.Last).Last_Subprogram_Name;
6529 Body_Id : constant Entity_Id :=
6530 Defining_Entity (Specification (N));
6533 Get_Decoded_Name_String (Chars (Body_Id));
6536 if Subprogram_Name_Greater
6537 (LSN.all, Name_Buffer (1 .. Name_Len))
6539 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6545 LSN := new String'(Name_Buffer (1 .. Name_Len));
6548 end Check_Subprogram_Order;
6550 ------------------------------
6551 -- Check_Subtype_Conformant --
6552 ------------------------------
6554 procedure Check_Subtype_Conformant
6555 (New_Id : Entity_Id;
6557 Err_Loc : Node_Id := Empty;
6558 Skip_Controlling_Formals : Boolean := False;
6559 Get_Inst : Boolean := False)
6562 pragma Warnings (Off, Result);
6565 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6566 Skip_Controlling_Formals => Skip_Controlling_Formals,
6567 Get_Inst => Get_Inst);
6568 end Check_Subtype_Conformant;
6570 -----------------------------------
6571 -- Check_Synchronized_Overriding --
6572 -----------------------------------
6574 procedure Check_Synchronized_Overriding
6575 (Def_Id : Entity_Id;
6576 Overridden_Subp : out Entity_Id)
6578 Ifaces_List : Elist_Id;
6582 function Matches_Prefixed_View_Profile
6583 (Prim_Params : List_Id;
6584 Iface_Params : List_Id) return Boolean;
6585 -- Determine whether a subprogram's parameter profile Prim_Params
6586 -- matches that of a potentially overridden interface subprogram
6587 -- Iface_Params. Also determine if the type of first parameter of
6588 -- Iface_Params is an implemented interface.
6590 -----------------------------------
6591 -- Matches_Prefixed_View_Profile --
6592 -----------------------------------
6594 function Matches_Prefixed_View_Profile
6595 (Prim_Params : List_Id;
6596 Iface_Params : List_Id) return Boolean
6598 function Is_Implemented
6599 (Ifaces_List : Elist_Id;
6600 Iface : Entity_Id) return Boolean;
6601 -- Determine if Iface is implemented by the current task or
6604 --------------------
6605 -- Is_Implemented --
6606 --------------------
6608 function Is_Implemented
6609 (Ifaces_List : Elist_Id;
6610 Iface : Entity_Id) return Boolean
6612 Iface_Elmt : Elmt_Id;
6615 Iface_Elmt := First_Elmt (Ifaces_List);
6616 while Present (Iface_Elmt) loop
6617 if Node (Iface_Elmt) = Iface then
6621 Next_Elmt (Iface_Elmt);
6629 Iface_Id : Entity_Id;
6630 Iface_Param : Node_Id;
6631 Iface_Typ : Entity_Id;
6632 Prim_Id : Entity_Id;
6633 Prim_Param : Node_Id;
6634 Prim_Typ : Entity_Id;
6636 -- Start of processing for Matches_Prefixed_View_Profile
6639 Iface_Param := First (Iface_Params);
6640 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
6642 if Is_Access_Type (Iface_Typ) then
6643 Iface_Typ := Designated_Type (Iface_Typ);
6646 Prim_Param := First (Prim_Params);
6648 -- The first parameter of the potentially overridden subprogram must
6649 -- be an interface implemented by Prim.
6651 if not Is_Interface (Iface_Typ)
6652 or else not Is_Implemented (Ifaces_List, Iface_Typ)
6657 -- The checks on the object parameters are done, so move on to the
6658 -- rest of the parameters.
6660 if not In_Scope then
6661 Prim_Param := Next (Prim_Param);
6664 Iface_Param := Next (Iface_Param);
6665 while Present (Iface_Param) and then Present (Prim_Param) loop
6666 Iface_Id := Defining_Identifier (Iface_Param);
6667 Iface_Typ := Find_Parameter_Type (Iface_Param);
6669 Prim_Id := Defining_Identifier (Prim_Param);
6670 Prim_Typ := Find_Parameter_Type (Prim_Param);
6672 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
6673 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
6674 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
6676 Iface_Typ := Designated_Type (Iface_Typ);
6677 Prim_Typ := Designated_Type (Prim_Typ);
6680 -- Case of multiple interface types inside a parameter profile
6682 -- (Obj_Param : in out Iface; ...; Param : Iface)
6684 -- If the interface type is implemented, then the matching type in
6685 -- the primitive should be the implementing record type.
6687 if Ekind (Iface_Typ) = E_Record_Type
6688 and then Is_Interface (Iface_Typ)
6689 and then Is_Implemented (Ifaces_List, Iface_Typ)
6691 if Prim_Typ /= Typ then
6695 -- The two parameters must be both mode and subtype conformant
6697 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
6699 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
6708 -- One of the two lists contains more parameters than the other
6710 if Present (Iface_Param) or else Present (Prim_Param) then
6715 end Matches_Prefixed_View_Profile;
6717 -- Start of processing for Check_Synchronized_Overriding
6720 Overridden_Subp := Empty;
6722 -- Def_Id must be an entry or a subprogram. We should skip predefined
6723 -- primitives internally generated by the front end; however at this
6724 -- stage predefined primitives are still not fully decorated. As a
6725 -- minor optimization we skip here internally generated subprograms.
6727 if (Ekind (Def_Id) /= E_Entry
6728 and then Ekind (Def_Id) /= E_Function
6729 and then Ekind (Def_Id) /= E_Procedure)
6730 or else not Comes_From_Source (Def_Id)
6735 -- Search for the concurrent declaration since it contains the list of
6736 -- all implemented interfaces. In this case, the subprogram is declared
6737 -- within the scope of a protected or a task type.
6739 if Present (Scope (Def_Id))
6740 and then Is_Concurrent_Type (Scope (Def_Id))
6741 and then not Is_Generic_Actual_Type (Scope (Def_Id))
6743 Typ := Scope (Def_Id);
6746 -- The enclosing scope is not a synchronized type and the subprogram
6749 elsif No (First_Formal (Def_Id)) then
6752 -- The subprogram has formals and hence it may be a primitive of a
6756 Typ := Etype (First_Formal (Def_Id));
6758 if Is_Access_Type (Typ) then
6759 Typ := Directly_Designated_Type (Typ);
6762 if Is_Concurrent_Type (Typ)
6763 and then not Is_Generic_Actual_Type (Typ)
6767 -- This case occurs when the concurrent type is declared within a
6768 -- generic unit. As a result the corresponding record has been built
6769 -- and used as the type of the first formal, we just have to retrieve
6770 -- the corresponding concurrent type.
6772 elsif Is_Concurrent_Record_Type (Typ)
6773 and then not Is_Class_Wide_Type (Typ)
6774 and then Present (Corresponding_Concurrent_Type (Typ))
6776 Typ := Corresponding_Concurrent_Type (Typ);
6784 -- There is no overriding to check if this is an inherited operation in
6785 -- a type derivation for a generic actual.
6787 Collect_Interfaces (Typ, Ifaces_List);
6789 if Is_Empty_Elmt_List (Ifaces_List) then
6793 -- Determine whether entry or subprogram Def_Id overrides a primitive
6794 -- operation that belongs to one of the interfaces in Ifaces_List.
6797 Candidate : Entity_Id := Empty;
6798 Hom : Entity_Id := Empty;
6799 Subp : Entity_Id := Empty;
6802 -- Traverse the homonym chain, looking for a potentially overridden
6803 -- subprogram that belongs to an implemented interface.
6805 Hom := Current_Entity_In_Scope (Def_Id);
6806 while Present (Hom) loop
6810 or else not Is_Overloadable (Subp)
6811 or else not Is_Primitive (Subp)
6812 or else not Is_Dispatching_Operation (Subp)
6813 or else not Present (Find_Dispatching_Type (Subp))
6814 or else not Is_Interface (Find_Dispatching_Type (Subp))
6818 -- Entries and procedures can override abstract or null interface
6821 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
6822 and then Ekind (Subp) = E_Procedure
6823 and then Matches_Prefixed_View_Profile
6824 (Parameter_Specifications (Parent (Def_Id)),
6825 Parameter_Specifications (Parent (Subp)))
6829 -- For an overridden subprogram Subp, check whether the mode
6830 -- of its first parameter is correct depending on the kind of
6831 -- synchronized type.
6834 Formal : constant Node_Id := First_Formal (Candidate);
6837 -- In order for an entry or a protected procedure to
6838 -- override, the first parameter of the overridden routine
6839 -- must be of mode "out", "in out", or access-to-variable.
6841 if Ekind_In (Candidate, E_Entry, E_Procedure)
6842 and then Is_Protected_Type (Typ)
6843 and then Ekind (Formal) /= E_In_Out_Parameter
6844 and then Ekind (Formal) /= E_Out_Parameter
6845 and then Nkind (Parameter_Type (Parent (Formal))) /=
6850 -- All other cases are OK since a task entry or routine does
6851 -- not have a restriction on the mode of the first parameter
6852 -- of the overridden interface routine.
6855 Overridden_Subp := Candidate;
6860 -- Functions can override abstract interface functions
6862 elsif Ekind (Def_Id) = E_Function
6863 and then Ekind (Subp) = E_Function
6864 and then Matches_Prefixed_View_Profile
6865 (Parameter_Specifications (Parent (Def_Id)),
6866 Parameter_Specifications (Parent (Subp)))
6867 and then Etype (Def_Id) = Etype (Subp)
6871 -- If an inherited subprogram is implemented by a protected
6872 -- function, then the first parameter of the inherited
6873 -- subprogram shall be of mode in, but not an access-to-
6874 -- variable parameter (RM 9.4(11/9)).
6876 if Present (First_Formal (Subp))
6877 and then Ekind (First_Formal (Subp)) = E_In_Parameter
6879 (not Is_Access_Type (Etype (First_Formal (Subp)))
6881 Is_Access_Constant (Etype (First_Formal (Subp))))
6883 Overridden_Subp := Subp;
6888 Hom := Homonym (Hom);
6891 -- After examining all candidates for overriding, we are left with
6892 -- the best match, which is a mode-incompatible interface routine.
6894 if In_Scope and then Present (Candidate) then
6895 Error_Msg_PT (Def_Id, Candidate);
6898 Overridden_Subp := Candidate;
6901 end Check_Synchronized_Overriding;
6903 ---------------------------
6904 -- Check_Type_Conformant --
6905 ---------------------------
6907 procedure Check_Type_Conformant
6908 (New_Id : Entity_Id;
6910 Err_Loc : Node_Id := Empty)
6913 pragma Warnings (Off, Result);
6916 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
6917 end Check_Type_Conformant;
6919 ---------------------------
6920 -- Can_Override_Operator --
6921 ---------------------------
6923 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
6927 if Nkind (Subp) /= N_Defining_Operator_Symbol then
6931 Typ := Base_Type (Etype (First_Formal (Subp)));
6933 -- Check explicitly that the operation is a primitive of the type
6935 return Operator_Matches_Spec (Subp, Subp)
6936 and then not Is_Generic_Type (Typ)
6937 and then Scope (Subp) = Scope (Typ)
6938 and then not Is_Class_Wide_Type (Typ);
6940 end Can_Override_Operator;
6942 ----------------------
6943 -- Conforming_Types --
6944 ----------------------
6946 function Conforming_Types
6949 Ctype : Conformance_Type;
6950 Get_Inst : Boolean := False) return Boolean
6952 function Base_Types_Match
6954 Typ_2 : Entity_Id) return Boolean;
6955 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
6956 -- in different scopes (e.g. parent and child instances), then verify
6957 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
6958 -- the same subtype chain. The whole purpose of this procedure is to
6959 -- prevent spurious ambiguities in an instantiation that may arise if
6960 -- two distinct generic types are instantiated with the same actual.
6962 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
6963 -- An access parameter can designate an incomplete type. If the
6964 -- incomplete type is the limited view of a type from a limited_
6965 -- with_clause, check whether the non-limited view is available.
6966 -- If it is a (non-limited) incomplete type, get the full view.
6968 function Matches_Limited_With_View
6970 Typ_2 : Entity_Id) return Boolean;
6971 -- Returns True if and only if either Typ_1 denotes a limited view of
6972 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
6973 -- the limited with view of a type is used in a subprogram declaration
6974 -- and the subprogram body is in the scope of a regular with clause for
6975 -- the same unit. In such a case, the two type entities are considered
6976 -- identical for purposes of conformance checking.
6978 ----------------------
6979 -- Base_Types_Match --
6980 ----------------------
6982 function Base_Types_Match
6984 Typ_2 : Entity_Id) return Boolean
6986 Base_1 : constant Entity_Id := Base_Type (Typ_1);
6987 Base_2 : constant Entity_Id := Base_Type (Typ_2);
6990 if Typ_1 = Typ_2 then
6993 elsif Base_1 = Base_2 then
6995 -- The following is too permissive. A more precise test should
6996 -- check that the generic actual is an ancestor subtype of the
6999 -- See code in Find_Corresponding_Spec that applies an additional
7000 -- filter to handle accidental amiguities in instances.
7003 not Is_Generic_Actual_Type (Typ_1)
7004 or else not Is_Generic_Actual_Type (Typ_2)
7005 or else Scope (Typ_1) /= Scope (Typ_2);
7007 -- If Typ_2 is a generic actual type it is declared as the subtype of
7008 -- the actual. If that actual is itself a subtype we need to use its
7009 -- own base type to check for compatibility.
7011 elsif Ekind (Base_2) = Ekind (Typ_2)
7012 and then Base_1 = Base_Type (Base_2)
7016 elsif Ekind (Base_1) = Ekind (Typ_1)
7017 and then Base_2 = Base_Type (Base_1)
7024 end Base_Types_Match;
7026 --------------------------
7027 -- Find_Designated_Type --
7028 --------------------------
7030 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7034 Desig := Directly_Designated_Type (Typ);
7036 if Ekind (Desig) = E_Incomplete_Type then
7038 -- If regular incomplete type, get full view if available
7040 if Present (Full_View (Desig)) then
7041 Desig := Full_View (Desig);
7043 -- If limited view of a type, get non-limited view if available,
7044 -- and check again for a regular incomplete type.
7046 elsif Present (Non_Limited_View (Desig)) then
7047 Desig := Get_Full_View (Non_Limited_View (Desig));
7052 end Find_Designated_Type;
7054 -------------------------------
7055 -- Matches_Limited_With_View --
7056 -------------------------------
7058 function Matches_Limited_With_View
7060 Typ_2 : Entity_Id) return Boolean
7062 function Is_Matching_Limited_View
7064 View : Entity_Id) return Boolean;
7065 -- Determine whether non-limited view View denotes type Typ in some
7066 -- conformant fashion.
7068 ------------------------------
7069 -- Is_Matching_Limited_View --
7070 ------------------------------
7072 function Is_Matching_Limited_View
7074 View : Entity_Id) return Boolean
7076 Root_Typ : Entity_Id;
7077 Root_View : Entity_Id;
7080 -- The non-limited view directly denotes the type
7085 -- The type is a subtype of the non-limited view
7087 elsif Is_Subtype_Of (Typ, View) then
7090 -- Both the non-limited view and the type denote class-wide types
7092 elsif Is_Class_Wide_Type (Typ)
7093 and then Is_Class_Wide_Type (View)
7095 Root_Typ := Root_Type (Typ);
7096 Root_View := Root_Type (View);
7098 if Root_Typ = Root_View then
7101 -- An incomplete tagged type and its full view may receive two
7102 -- distinct class-wide types when the related package has not
7103 -- been analyzed yet.
7106 -- type T is tagged; -- CW_1
7107 -- type T is tagged null record; -- CW_2
7110 -- This is because the package lacks any semantic information
7111 -- that may eventually link both views of T. As a consequence,
7112 -- a client of the limited view of Pack will see CW_2 while a
7113 -- client of the non-limited view of Pack will see CW_1.
7115 elsif Is_Incomplete_Type (Root_Typ)
7116 and then Present (Full_View (Root_Typ))
7117 and then Full_View (Root_Typ) = Root_View
7121 elsif Is_Incomplete_Type (Root_View)
7122 and then Present (Full_View (Root_View))
7123 and then Full_View (Root_View) = Root_Typ
7130 end Is_Matching_Limited_View;
7132 -- Start of processing for Matches_Limited_With_View
7135 -- In some cases a type imported through a limited_with clause, and
7136 -- its non-limited view are both visible, for example in an anonymous
7137 -- access-to-class-wide type in a formal, or when building the body
7138 -- for a subprogram renaming after the subprogram has been frozen.
7139 -- In these cases both entities designate the same type. In addition,
7140 -- if one of them is an actual in an instance, it may be a subtype of
7141 -- the non-limited view of the other.
7143 if From_Limited_With (Typ_1)
7144 and then From_Limited_With (Typ_2)
7145 and then Available_View (Typ_1) = Available_View (Typ_2)
7149 elsif From_Limited_With (Typ_1) then
7150 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7152 elsif From_Limited_With (Typ_2) then
7153 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7158 end Matches_Limited_With_View;
7162 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7164 Type_1 : Entity_Id := T1;
7165 Type_2 : Entity_Id := T2;
7167 -- Start of processing for Conforming_Types
7170 -- The context is an instance association for a formal access-to-
7171 -- subprogram type; the formal parameter types require mapping because
7172 -- they may denote other formal parameters of the generic unit.
7175 Type_1 := Get_Instance_Of (T1);
7176 Type_2 := Get_Instance_Of (T2);
7179 -- If one of the types is a view of the other introduced by a limited
7180 -- with clause, treat these as conforming for all purposes.
7182 if Matches_Limited_With_View (T1, T2) then
7185 elsif Base_Types_Match (Type_1, Type_2) then
7186 return Ctype <= Mode_Conformant
7187 or else Subtypes_Statically_Match (Type_1, Type_2);
7189 elsif Is_Incomplete_Or_Private_Type (Type_1)
7190 and then Present (Full_View (Type_1))
7191 and then Base_Types_Match (Full_View (Type_1), Type_2)
7193 return Ctype <= Mode_Conformant
7194 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7196 elsif Ekind (Type_2) = E_Incomplete_Type
7197 and then Present (Full_View (Type_2))
7198 and then Base_Types_Match (Type_1, Full_View (Type_2))
7200 return Ctype <= Mode_Conformant
7201 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7203 elsif Is_Private_Type (Type_2)
7204 and then In_Instance
7205 and then Present (Full_View (Type_2))
7206 and then Base_Types_Match (Type_1, Full_View (Type_2))
7208 return Ctype <= Mode_Conformant
7209 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7211 -- Another confusion between views in a nested instance with an
7212 -- actual private type whose full view is not in scope.
7214 elsif Ekind (Type_2) = E_Private_Subtype
7215 and then In_Instance
7216 and then Etype (Type_2) = Type_1
7220 -- In Ada 2012, incomplete types (including limited views) can appear
7221 -- as actuals in instantiations.
7223 elsif Is_Incomplete_Type (Type_1)
7224 and then Is_Incomplete_Type (Type_2)
7225 and then (Used_As_Generic_Actual (Type_1)
7226 or else Used_As_Generic_Actual (Type_2))
7231 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7232 -- treated recursively because they carry a signature. As far as
7233 -- conformance is concerned, convention plays no role, and either
7234 -- or both could be access to protected subprograms.
7236 Are_Anonymous_Access_To_Subprogram_Types :=
7237 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7238 E_Anonymous_Access_Protected_Subprogram_Type)
7240 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7241 E_Anonymous_Access_Protected_Subprogram_Type);
7243 -- Test anonymous access type case. For this case, static subtype
7244 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7245 -- the base types because we may have built internal subtype entities
7246 -- to handle null-excluding types (see Process_Formals).
7248 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7250 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7252 -- Ada 2005 (AI-254)
7254 or else Are_Anonymous_Access_To_Subprogram_Types
7257 Desig_1 : Entity_Id;
7258 Desig_2 : Entity_Id;
7261 -- In Ada 2005, access constant indicators must match for
7262 -- subtype conformance.
7264 if Ada_Version >= Ada_2005
7265 and then Ctype >= Subtype_Conformant
7267 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7272 Desig_1 := Find_Designated_Type (Type_1);
7273 Desig_2 := Find_Designated_Type (Type_2);
7275 -- If the context is an instance association for a formal
7276 -- access-to-subprogram type; formal access parameter designated
7277 -- types require mapping because they may denote other formal
7278 -- parameters of the generic unit.
7281 Desig_1 := Get_Instance_Of (Desig_1);
7282 Desig_2 := Get_Instance_Of (Desig_2);
7285 -- It is possible for a Class_Wide_Type to be introduced for an
7286 -- incomplete type, in which case there is a separate class_ wide
7287 -- type for the full view. The types conform if their Etypes
7288 -- conform, i.e. one may be the full view of the other. This can
7289 -- only happen in the context of an access parameter, other uses
7290 -- of an incomplete Class_Wide_Type are illegal.
7292 if Is_Class_Wide_Type (Desig_1)
7294 Is_Class_Wide_Type (Desig_2)
7298 (Etype (Base_Type (Desig_1)),
7299 Etype (Base_Type (Desig_2)), Ctype);
7301 elsif Are_Anonymous_Access_To_Subprogram_Types then
7302 if Ada_Version < Ada_2005 then
7303 return Ctype = Type_Conformant
7305 Subtypes_Statically_Match (Desig_1, Desig_2);
7307 -- We must check the conformance of the signatures themselves
7311 Conformant : Boolean;
7314 (Desig_1, Desig_2, Ctype, False, Conformant);
7319 -- A limited view of an actual matches the corresponding
7320 -- incomplete formal.
7322 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7323 and then From_Limited_With (Desig_2)
7324 and then Used_As_Generic_Actual (Etype (Desig_2))
7329 return Base_Type (Desig_1) = Base_Type (Desig_2)
7330 and then (Ctype = Type_Conformant
7332 Subtypes_Statically_Match (Desig_1, Desig_2));
7336 -- Otherwise definitely no match
7339 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7340 and then Is_Access_Type (Type_2))
7341 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7342 and then Is_Access_Type (Type_1)))
7345 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7347 May_Hide_Profile := True;
7352 end Conforming_Types;
7354 --------------------------
7355 -- Create_Extra_Formals --
7356 --------------------------
7358 procedure Create_Extra_Formals (E : Entity_Id) is
7359 First_Extra : Entity_Id := Empty;
7361 Last_Extra : Entity_Id := Empty;
7363 function Add_Extra_Formal
7364 (Assoc_Entity : Entity_Id;
7367 Suffix : String) return Entity_Id;
7368 -- Add an extra formal to the current list of formals and extra formals.
7369 -- The extra formal is added to the end of the list of extra formals,
7370 -- and also returned as the result. These formals are always of mode IN.
7371 -- The new formal has the type Typ, is declared in Scope, and its name
7372 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7373 -- The following suffixes are currently used. They should not be changed
7374 -- without coordinating with CodePeer, which makes use of these to
7375 -- provide better messages.
7377 -- O denotes the Constrained bit.
7378 -- L denotes the accessibility level.
7379 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7380 -- the full list in exp_ch6.BIP_Formal_Kind.
7382 ----------------------
7383 -- Add_Extra_Formal --
7384 ----------------------
7386 function Add_Extra_Formal
7387 (Assoc_Entity : Entity_Id;
7390 Suffix : String) return Entity_Id
7392 EF : constant Entity_Id :=
7393 Make_Defining_Identifier (Sloc (Assoc_Entity),
7394 Chars => New_External_Name (Chars (Assoc_Entity),
7398 -- A little optimization. Never generate an extra formal for the
7399 -- _init operand of an initialization procedure, since it could
7402 if Chars (Formal) = Name_uInit then
7406 Set_Ekind (EF, E_In_Parameter);
7407 Set_Actual_Subtype (EF, Typ);
7408 Set_Etype (EF, Typ);
7409 Set_Scope (EF, Scope);
7410 Set_Mechanism (EF, Default_Mechanism);
7411 Set_Formal_Validity (EF);
7413 if No (First_Extra) then
7415 Set_Extra_Formals (Scope, First_Extra);
7418 if Present (Last_Extra) then
7419 Set_Extra_Formal (Last_Extra, EF);
7425 end Add_Extra_Formal;
7429 Formal_Type : Entity_Id;
7430 P_Formal : Entity_Id := Empty;
7432 -- Start of processing for Create_Extra_Formals
7435 -- We never generate extra formals if expansion is not active because we
7436 -- don't need them unless we are generating code.
7438 if not Expander_Active then
7442 -- No need to generate extra formals in interface thunks whose target
7443 -- primitive has no extra formals.
7445 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7449 -- If this is a derived subprogram then the subtypes of the parent
7450 -- subprogram's formal parameters will be used to determine the need
7451 -- for extra formals.
7453 if Is_Overloadable (E) and then Present (Alias (E)) then
7454 P_Formal := First_Formal (Alias (E));
7457 Formal := First_Formal (E);
7458 while Present (Formal) loop
7459 Last_Extra := Formal;
7460 Next_Formal (Formal);
7463 -- If Extra_Formals were already created, don't do it again. This
7464 -- situation may arise for subprogram types created as part of
7465 -- dispatching calls (see Expand_Dispatching_Call)
7467 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7471 -- If the subprogram is a predefined dispatching subprogram then don't
7472 -- generate any extra constrained or accessibility level formals. In
7473 -- general we suppress these for internal subprograms (by not calling
7474 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7475 -- generated stream attributes do get passed through because extra
7476 -- build-in-place formals are needed in some cases (limited 'Input).
7478 if Is_Predefined_Internal_Operation (E) then
7479 goto Test_For_Func_Result_Extras;
7482 Formal := First_Formal (E);
7483 while Present (Formal) loop
7485 -- Create extra formal for supporting the attribute 'Constrained.
7486 -- The case of a private type view without discriminants also
7487 -- requires the extra formal if the underlying type has defaulted
7490 if Ekind (Formal) /= E_In_Parameter then
7491 if Present (P_Formal) then
7492 Formal_Type := Etype (P_Formal);
7494 Formal_Type := Etype (Formal);
7497 -- Do not produce extra formals for Unchecked_Union parameters.
7498 -- Jump directly to the end of the loop.
7500 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7501 goto Skip_Extra_Formal_Generation;
7504 if not Has_Discriminants (Formal_Type)
7505 and then Ekind (Formal_Type) in Private_Kind
7506 and then Present (Underlying_Type (Formal_Type))
7508 Formal_Type := Underlying_Type (Formal_Type);
7511 -- Suppress the extra formal if formal's subtype is constrained or
7512 -- indefinite, or we're compiling for Ada 2012 and the underlying
7513 -- type is tagged and limited. In Ada 2012, a limited tagged type
7514 -- can have defaulted discriminants, but 'Constrained is required
7515 -- to return True, so the formal is never needed (see AI05-0214).
7516 -- Note that this ensures consistency of calling sequences for
7517 -- dispatching operations when some types in a class have defaults
7518 -- on discriminants and others do not (and requiring the extra
7519 -- formal would introduce distributed overhead).
7521 -- If the type does not have a completion yet, treat as prior to
7522 -- Ada 2012 for consistency.
7524 if Has_Discriminants (Formal_Type)
7525 and then not Is_Constrained (Formal_Type)
7526 and then Is_Definite_Subtype (Formal_Type)
7527 and then (Ada_Version < Ada_2012
7528 or else No (Underlying_Type (Formal_Type))
7530 (Is_Limited_Type (Formal_Type)
7533 (Underlying_Type (Formal_Type)))))
7535 Set_Extra_Constrained
7536 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7540 -- Create extra formal for supporting accessibility checking. This
7541 -- is done for both anonymous access formals and formals of named
7542 -- access types that are marked as controlling formals. The latter
7543 -- case can occur when Expand_Dispatching_Call creates a subprogram
7544 -- type and substitutes the types of access-to-class-wide actuals
7545 -- for the anonymous access-to-specific-type of controlling formals.
7546 -- Base_Type is applied because in cases where there is a null
7547 -- exclusion the formal may have an access subtype.
7549 -- This is suppressed if we specifically suppress accessibility
7550 -- checks at the package level for either the subprogram, or the
7551 -- package in which it resides. However, we do not suppress it
7552 -- simply if the scope has accessibility checks suppressed, since
7553 -- this could cause trouble when clients are compiled with a
7554 -- different suppression setting. The explicit checks at the
7555 -- package level are safe from this point of view.
7557 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7558 or else (Is_Controlling_Formal (Formal)
7559 and then Is_Access_Type (Base_Type (Etype (Formal)))))
7561 (Explicit_Suppress (E, Accessibility_Check)
7563 Explicit_Suppress (Scope (E), Accessibility_Check))
7566 or else Present (Extra_Accessibility (P_Formal)))
7568 Set_Extra_Accessibility
7569 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
7572 -- This label is required when skipping extra formal generation for
7573 -- Unchecked_Union parameters.
7575 <<Skip_Extra_Formal_Generation>>
7577 if Present (P_Formal) then
7578 Next_Formal (P_Formal);
7581 Next_Formal (Formal);
7584 <<Test_For_Func_Result_Extras>>
7586 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
7587 -- function call is ... determined by the point of call ...".
7589 if Needs_Result_Accessibility_Level (E) then
7590 Set_Extra_Accessibility_Of_Result
7591 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
7594 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
7595 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
7597 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
7599 Result_Subt : constant Entity_Id := Etype (E);
7600 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
7601 Formal_Typ : Entity_Id;
7602 Subp_Decl : Node_Id;
7604 Discard : Entity_Id;
7605 pragma Warnings (Off, Discard);
7608 -- In the case of functions with unconstrained result subtypes,
7609 -- add a 4-state formal indicating whether the return object is
7610 -- allocated by the caller (1), or should be allocated by the
7611 -- callee on the secondary stack (2), in the global heap (3), or
7612 -- in a user-defined storage pool (4). For the moment we just use
7613 -- Natural for the type of this formal. Note that this formal
7614 -- isn't usually needed in the case where the result subtype is
7615 -- constrained, but it is needed when the function has a tagged
7616 -- result, because generally such functions can be called in a
7617 -- dispatching context and such calls must be handled like calls
7618 -- to a class-wide function.
7620 if Needs_BIP_Alloc_Form (E) then
7623 (E, Standard_Natural,
7624 E, BIP_Formal_Suffix (BIP_Alloc_Form));
7626 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
7627 -- use a user-defined pool. This formal is not added on
7628 -- ZFP as those targets do not support pools.
7630 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
7633 (E, RTE (RE_Root_Storage_Pool_Ptr),
7634 E, BIP_Formal_Suffix (BIP_Storage_Pool));
7638 -- In the case of functions whose result type needs finalization,
7639 -- add an extra formal which represents the finalization master.
7641 if Needs_BIP_Finalization_Master (E) then
7644 (E, RTE (RE_Finalization_Master_Ptr),
7645 E, BIP_Formal_Suffix (BIP_Finalization_Master));
7648 -- When the result type contains tasks, add two extra formals: the
7649 -- master of the tasks to be created, and the caller's activation
7652 if Has_Task (Full_Subt) then
7655 (E, RTE (RE_Master_Id),
7656 E, BIP_Formal_Suffix (BIP_Task_Master));
7659 (E, RTE (RE_Activation_Chain_Access),
7660 E, BIP_Formal_Suffix (BIP_Activation_Chain));
7663 -- All build-in-place functions get an extra formal that will be
7664 -- passed the address of the return object within the caller.
7667 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
7669 Set_Directly_Designated_Type (Formal_Typ, Result_Subt);
7670 Set_Etype (Formal_Typ, Formal_Typ);
7671 Set_Depends_On_Private
7672 (Formal_Typ, Has_Private_Component (Formal_Typ));
7673 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
7674 Set_Is_Access_Constant (Formal_Typ, False);
7676 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
7677 -- the designated type comes from the limited view (for back-end
7680 Set_From_Limited_With
7681 (Formal_Typ, From_Limited_With (Result_Subt));
7683 Layout_Type (Formal_Typ);
7685 -- Force the definition of the Itype in case of internal function
7686 -- calls within the same or nested scope.
7688 if Is_Subprogram_Or_Generic_Subprogram (E) then
7689 Subp_Decl := Parent (E);
7691 -- The insertion point for an Itype reference should be after
7692 -- the unit declaration node of the subprogram. An exception
7693 -- to this are inherited operations from a parent type in which
7694 -- case the derived type acts as their parent.
7696 if Nkind_In (Subp_Decl, N_Function_Specification,
7697 N_Procedure_Specification)
7699 Subp_Decl := Parent (Subp_Decl);
7702 Build_Itype_Reference (Formal_Typ, Subp_Decl);
7707 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
7710 end Create_Extra_Formals;
7712 -----------------------------
7713 -- Enter_Overloaded_Entity --
7714 -----------------------------
7716 procedure Enter_Overloaded_Entity (S : Entity_Id) is
7717 function Matches_Predefined_Op return Boolean;
7718 -- This returns an approximation of whether S matches a predefined
7719 -- operator, based on the operator symbol, and the parameter and result
7720 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
7722 ---------------------------
7723 -- Matches_Predefined_Op --
7724 ---------------------------
7726 function Matches_Predefined_Op return Boolean is
7727 Formal_1 : constant Entity_Id := First_Formal (S);
7728 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
7729 Op : constant Name_Id := Chars (S);
7730 Result_Type : constant Entity_Id := Base_Type (Etype (S));
7731 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
7736 if Present (Formal_2) then
7738 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
7741 -- All but "&" and "**" have same-types parameters
7744 when Name_Op_Concat |
7749 if Type_1 /= Type_2 then
7754 -- Check parameter and result types
7761 Is_Boolean_Type (Result_Type)
7762 and then Result_Type = Type_1;
7767 Is_Integer_Type (Result_Type)
7768 and then Result_Type = Type_1;
7775 Is_Numeric_Type (Result_Type)
7776 and then Result_Type = Type_1;
7781 Is_Boolean_Type (Result_Type)
7782 and then not Is_Limited_Type (Type_1);
7789 Is_Boolean_Type (Result_Type)
7790 and then (Is_Array_Type (Type_1)
7791 or else Is_Scalar_Type (Type_1));
7793 when Name_Op_Concat =>
7794 return Is_Array_Type (Result_Type);
7796 when Name_Op_Expon =>
7798 (Is_Integer_Type (Result_Type)
7799 or else Is_Floating_Point_Type (Result_Type))
7800 and then Result_Type = Type_1
7801 and then Type_2 = Standard_Integer;
7804 raise Program_Error;
7816 Is_Numeric_Type (Result_Type)
7817 and then Result_Type = Type_1;
7821 Is_Boolean_Type (Result_Type)
7822 and then Result_Type = Type_1;
7825 raise Program_Error;
7828 end Matches_Predefined_Op;
7832 E : Entity_Id := Current_Entity_In_Scope (S);
7833 C_E : Entity_Id := Current_Entity (S);
7835 -- Start of processing for Enter_Overloaded_Entity
7839 Set_Has_Homonym (E);
7840 Set_Has_Homonym (S);
7843 Set_Is_Immediately_Visible (S);
7844 Set_Scope (S, Current_Scope);
7846 -- Chain new entity if front of homonym in current scope, so that
7847 -- homonyms are contiguous.
7849 if Present (E) and then E /= C_E then
7850 while Homonym (C_E) /= E loop
7851 C_E := Homonym (C_E);
7854 Set_Homonym (C_E, S);
7858 Set_Current_Entity (S);
7863 if Is_Inherited_Operation (S) then
7864 Append_Inherited_Subprogram (S);
7866 Append_Entity (S, Current_Scope);
7869 Set_Public_Status (S);
7871 if Debug_Flag_E then
7872 Write_Str ("New overloaded entity chain: ");
7873 Write_Name (Chars (S));
7876 while Present (E) loop
7877 Write_Str (" "); Write_Int (Int (E));
7884 -- Generate warning for hiding
7887 and then Comes_From_Source (S)
7888 and then In_Extended_Main_Source_Unit (S)
7895 -- Warn unless genuine overloading. Do not emit warning on
7896 -- hiding predefined operators in Standard (these are either an
7897 -- (artifact of our implicit declarations, or simple noise) but
7898 -- keep warning on a operator defined on a local subtype, because
7899 -- of the real danger that different operators may be applied in
7900 -- various parts of the program.
7902 -- Note that if E and S have the same scope, there is never any
7903 -- hiding. Either the two conflict, and the program is illegal,
7904 -- or S is overriding an implicit inherited subprogram.
7906 if Scope (E) /= Scope (S)
7907 and then (not Is_Overloadable (E)
7908 or else Subtype_Conformant (E, S))
7909 and then (Is_Immediately_Visible (E)
7910 or else Is_Potentially_Use_Visible (S))
7912 if Scope (E) = Standard_Standard then
7913 if Nkind (S) = N_Defining_Operator_Symbol
7914 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
7916 and then Matches_Predefined_Op
7919 ("declaration of & hides predefined operator?h?", S);
7922 -- E not immediately within Standard
7925 Error_Msg_Sloc := Sloc (E);
7926 Error_Msg_N ("declaration of & hides one #?h?", S);
7931 end Enter_Overloaded_Entity;
7933 -----------------------------
7934 -- Check_Untagged_Equality --
7935 -----------------------------
7937 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
7938 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
7939 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
7943 -- This check applies only if we have a subprogram declaration with an
7944 -- untagged record type.
7946 if Nkind (Decl) /= N_Subprogram_Declaration
7947 or else not Is_Record_Type (Typ)
7948 or else Is_Tagged_Type (Typ)
7953 -- In Ada 2012 case, we will output errors or warnings depending on
7954 -- the setting of debug flag -gnatd.E.
7956 if Ada_Version >= Ada_2012 then
7957 Error_Msg_Warn := Debug_Flag_Dot_EE;
7959 -- In earlier versions of Ada, nothing to do unless we are warning on
7960 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
7963 if not Warn_On_Ada_2012_Compatibility then
7968 -- Cases where the type has already been frozen
7970 if Is_Frozen (Typ) then
7972 -- If the type is not declared in a package, or if we are in the body
7973 -- of the package or in some other scope, the new operation is not
7974 -- primitive, and therefore legal, though suspicious. Should we
7975 -- generate a warning in this case ???
7977 if Ekind (Scope (Typ)) /= E_Package
7978 or else Scope (Typ) /= Current_Scope
7982 -- If the type is a generic actual (sub)type, the operation is not
7983 -- primitive either because the base type is declared elsewhere.
7985 elsif Is_Generic_Actual_Type (Typ) then
7988 -- Here we have a definite error of declaration after freezing
7991 if Ada_Version >= Ada_2012 then
7993 ("equality operator must be declared before type & is "
7994 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
7996 -- In Ada 2012 mode with error turned to warning, output one
7997 -- more warning to warn that the equality operation may not
7998 -- compose. This is the consequence of ignoring the error.
8000 if Error_Msg_Warn then
8001 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8006 ("equality operator must be declared before type& is "
8007 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8010 -- If we are in the package body, we could just move the
8011 -- declaration to the package spec, so add a message saying that.
8013 if In_Package_Body (Scope (Typ)) then
8014 if Ada_Version >= Ada_2012 then
8016 ("\move declaration to package spec<<", Eq_Op);
8019 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8022 -- Otherwise try to find the freezing point
8025 Obj_Decl := Next (Parent (Typ));
8026 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8027 if Nkind (Obj_Decl) = N_Object_Declaration
8028 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8030 -- Freezing point, output warnings
8032 if Ada_Version >= Ada_2012 then
8034 ("type& is frozen by declaration??", Obj_Decl, Typ);
8036 ("\an equality operator cannot be declared after "
8041 ("type& is frozen by declaration (Ada 2012)?y?",
8044 ("\an equality operator cannot be declared after "
8045 & "this point (Ada 2012)?y?",
8057 -- Here if type is not frozen yet. It is illegal to have a primitive
8058 -- equality declared in the private part if the type is visible.
8060 elsif not In_Same_List (Parent (Typ), Decl)
8061 and then not Is_Limited_Type (Typ)
8063 -- Shouldn't we give an RM reference here???
8065 if Ada_Version >= Ada_2012 then
8067 ("equality operator appears too late<<", Eq_Op);
8070 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8073 -- No error detected
8078 end Check_Untagged_Equality;
8080 -----------------------------
8081 -- Find_Corresponding_Spec --
8082 -----------------------------
8084 function Find_Corresponding_Spec
8086 Post_Error : Boolean := True) return Entity_Id
8088 Spec : constant Node_Id := Specification (N);
8089 Designator : constant Entity_Id := Defining_Entity (Spec);
8093 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8094 -- Even if fully conformant, a body may depend on a generic actual when
8095 -- the spec does not, or vice versa, in which case they were distinct
8096 -- entities in the generic.
8098 -------------------------------
8099 -- Different_Generic_Profile --
8100 -------------------------------
8102 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8105 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8106 -- Check that the types of corresponding formals have the same
8107 -- generic actual if any. We have to account for subtypes of a
8108 -- generic formal, declared between a spec and a body, which may
8109 -- appear distinct in an instance but matched in the generic, and
8110 -- the subtype may be used either in the spec or the body of the
8111 -- subprogram being checked.
8113 -------------------------
8114 -- Same_Generic_Actual --
8115 -------------------------
8117 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8119 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8120 -- Predicate to check whether S1 is a subtype of S2 in the source
8123 -------------------------
8124 -- Is_Declared_Subtype --
8125 -------------------------
8127 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8129 return Comes_From_Source (Parent (S1))
8130 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8131 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8132 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8133 end Is_Declared_Subtype;
8135 -- Start of processing for Same_Generic_Actual
8138 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8139 or else Is_Declared_Subtype (T1, T2)
8140 or else Is_Declared_Subtype (T2, T1);
8141 end Same_Generic_Actual;
8143 -- Start of processing for Different_Generic_Profile
8146 if not In_Instance then
8149 elsif Ekind (E) = E_Function
8150 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8155 F1 := First_Formal (Designator);
8156 F2 := First_Formal (E);
8157 while Present (F1) loop
8158 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8167 end Different_Generic_Profile;
8169 -- Start of processing for Find_Corresponding_Spec
8172 E := Current_Entity (Designator);
8173 while Present (E) loop
8175 -- We are looking for a matching spec. It must have the same scope,
8176 -- and the same name, and either be type conformant, or be the case
8177 -- of a library procedure spec and its body (which belong to one
8178 -- another regardless of whether they are type conformant or not).
8180 if Scope (E) = Current_Scope then
8181 if Current_Scope = Standard_Standard
8182 or else (Ekind (E) = Ekind (Designator)
8183 and then Type_Conformant (E, Designator))
8185 -- Within an instantiation, we know that spec and body are
8186 -- subtype conformant, because they were subtype conformant in
8187 -- the generic. We choose the subtype-conformant entity here as
8188 -- well, to resolve spurious ambiguities in the instance that
8189 -- were not present in the generic (i.e. when two different
8190 -- types are given the same actual). If we are looking for a
8191 -- spec to match a body, full conformance is expected.
8195 -- Inherit the convention and "ghostness" of the matching
8196 -- spec to ensure proper full and subtype conformance.
8198 Set_Convention (Designator, Convention (E));
8200 if Is_Ghost_Entity (E) then
8201 Set_Is_Ghost_Entity (Designator);
8204 -- Skip past subprogram bodies and subprogram renamings that
8205 -- may appear to have a matching spec, but that aren't fully
8206 -- conformant with it. That can occur in cases where an
8207 -- actual type causes unrelated homographs in the instance.
8209 if Nkind_In (N, N_Subprogram_Body,
8210 N_Subprogram_Renaming_Declaration)
8211 and then Present (Homonym (E))
8212 and then not Fully_Conformant (Designator, E)
8216 elsif not Subtype_Conformant (Designator, E) then
8219 elsif Different_Generic_Profile (E) then
8224 -- Ada 2012 (AI05-0165): For internally generated bodies of
8225 -- null procedures locate the internally generated spec. We
8226 -- enforce mode conformance since a tagged type may inherit
8227 -- from interfaces several null primitives which differ only
8228 -- in the mode of the formals.
8230 if not (Comes_From_Source (E))
8231 and then Is_Null_Procedure (E)
8232 and then not Mode_Conformant (Designator, E)
8236 -- For null procedures coming from source that are completions,
8237 -- analysis of the generated body will establish the link.
8239 elsif Comes_From_Source (E)
8240 and then Nkind (Spec) = N_Procedure_Specification
8241 and then Null_Present (Spec)
8245 -- Expression functions can be completions, but cannot be
8246 -- completed by an explicit body.
8248 elsif Comes_From_Source (E)
8249 and then Comes_From_Source (N)
8250 and then Nkind (N) = N_Subprogram_Body
8251 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8252 N_Expression_Function
8254 Error_Msg_Sloc := Sloc (E);
8255 Error_Msg_N ("body conflicts with expression function#", N);
8258 elsif not Has_Completion (E) then
8259 if Nkind (N) /= N_Subprogram_Body_Stub then
8260 Set_Corresponding_Spec (N, E);
8263 Set_Has_Completion (E);
8266 elsif Nkind (Parent (N)) = N_Subunit then
8268 -- If this is the proper body of a subunit, the completion
8269 -- flag is set when analyzing the stub.
8273 -- If E is an internal function with a controlling result that
8274 -- was created for an operation inherited by a null extension,
8275 -- it may be overridden by a body without a previous spec (one
8276 -- more reason why these should be shunned). In that case we
8277 -- remove the generated body if present, because the current
8278 -- one is the explicit overriding.
8280 elsif Ekind (E) = E_Function
8281 and then Ada_Version >= Ada_2005
8282 and then not Comes_From_Source (E)
8283 and then Has_Controlling_Result (E)
8284 and then Is_Null_Extension (Etype (E))
8285 and then Comes_From_Source (Spec)
8287 Set_Has_Completion (E, False);
8290 and then Nkind (Parent (E)) = N_Function_Specification
8293 (Unit_Declaration_Node
8294 (Corresponding_Body (Unit_Declaration_Node (E))));
8298 -- If expansion is disabled, or if the wrapper function has
8299 -- not been generated yet, this a late body overriding an
8300 -- inherited operation, or it is an overriding by some other
8301 -- declaration before the controlling result is frozen. In
8302 -- either case this is a declaration of a new entity.
8308 -- If the body already exists, then this is an error unless
8309 -- the previous declaration is the implicit declaration of a
8310 -- derived subprogram. It is also legal for an instance to
8311 -- contain type conformant overloadable declarations (but the
8312 -- generic declaration may not), per 8.3(26/2).
8314 elsif No (Alias (E))
8315 and then not Is_Intrinsic_Subprogram (E)
8316 and then not In_Instance
8319 Error_Msg_Sloc := Sloc (E);
8321 if Is_Imported (E) then
8323 ("body not allowed for imported subprogram & declared#",
8326 Error_Msg_NE ("duplicate body for & declared#", N, E);
8330 -- Child units cannot be overloaded, so a conformance mismatch
8331 -- between body and a previous spec is an error.
8333 elsif Is_Child_Unit (E)
8335 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8337 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8342 ("body of child unit does not match previous declaration", N);
8350 -- On exit, we know that no previous declaration of subprogram exists
8353 end Find_Corresponding_Spec;
8355 ----------------------
8356 -- Fully_Conformant --
8357 ----------------------
8359 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8362 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8364 end Fully_Conformant;
8366 ----------------------------------
8367 -- Fully_Conformant_Expressions --
8368 ----------------------------------
8370 function Fully_Conformant_Expressions
8371 (Given_E1 : Node_Id;
8372 Given_E2 : Node_Id) return Boolean
8374 E1 : constant Node_Id := Original_Node (Given_E1);
8375 E2 : constant Node_Id := Original_Node (Given_E2);
8376 -- We always test conformance on original nodes, since it is possible
8377 -- for analysis and/or expansion to make things look as though they
8378 -- conform when they do not, e.g. by converting 1+2 into 3.
8380 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8381 renames Fully_Conformant_Expressions;
8383 function FCL (L1, L2 : List_Id) return Boolean;
8384 -- Compare elements of two lists for conformance. Elements have to be
8385 -- conformant, and actuals inserted as default parameters do not match
8386 -- explicit actuals with the same value.
8388 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8389 -- Compare an operator node with a function call
8395 function FCL (L1, L2 : List_Id) return Boolean is
8399 if L1 = No_List then
8405 if L2 = No_List then
8411 -- Compare two lists, skipping rewrite insertions (we want to compare
8412 -- the original trees, not the expanded versions).
8415 if Is_Rewrite_Insertion (N1) then
8417 elsif Is_Rewrite_Insertion (N2) then
8423 elsif not FCE (N1, N2) then
8436 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8437 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8442 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8447 Act := First (Actuals);
8449 if Nkind (Op_Node) in N_Binary_Op then
8450 if not FCE (Left_Opnd (Op_Node), Act) then
8457 return Present (Act)
8458 and then FCE (Right_Opnd (Op_Node), Act)
8459 and then No (Next (Act));
8463 -- Start of processing for Fully_Conformant_Expressions
8466 -- Non-conformant if paren count does not match. Note: if some idiot
8467 -- complains that we don't do this right for more than 3 levels of
8468 -- parentheses, they will be treated with the respect they deserve.
8470 if Paren_Count (E1) /= Paren_Count (E2) then
8473 -- If same entities are referenced, then they are conformant even if
8474 -- they have different forms (RM 8.3.1(19-20)).
8476 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8477 if Present (Entity (E1)) then
8478 return Entity (E1) = Entity (E2)
8480 -- One may be a discriminant that has been replaced by
8481 -- the correspondding discriminal
8483 or else (Chars (Entity (E1)) = Chars (Entity (E2))
8484 and then Ekind (Entity (E1)) = E_Discriminant
8485 and then Ekind (Entity (E2)) = E_In_Parameter)
8487 -- AI12-050 : the loop variables of quantified expressions
8488 -- match if the have the same identifier, even though they
8489 -- are different entities.
8491 or else (Chars (Entity (E1)) = Chars (Entity (E2))
8492 and then Ekind (Entity (E1)) = E_Loop_Parameter
8493 and then Ekind (Entity (E2)) = E_Loop_Parameter);
8495 elsif Nkind (E1) = N_Expanded_Name
8496 and then Nkind (E2) = N_Expanded_Name
8497 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8498 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8500 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8503 -- Identifiers in component associations don't always have
8504 -- entities, but their names must conform.
8506 return Nkind (E1) = N_Identifier
8507 and then Nkind (E2) = N_Identifier
8508 and then Chars (E1) = Chars (E2);
8511 elsif Nkind (E1) = N_Character_Literal
8512 and then Nkind (E2) = N_Expanded_Name
8514 return Nkind (Selector_Name (E2)) = N_Character_Literal
8515 and then Chars (E1) = Chars (Selector_Name (E2));
8517 elsif Nkind (E2) = N_Character_Literal
8518 and then Nkind (E1) = N_Expanded_Name
8520 return Nkind (Selector_Name (E1)) = N_Character_Literal
8521 and then Chars (E2) = Chars (Selector_Name (E1));
8523 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8524 return FCO (E1, E2);
8526 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8527 return FCO (E2, E1);
8529 -- Otherwise we must have the same syntactic entity
8531 elsif Nkind (E1) /= Nkind (E2) then
8534 -- At this point, we specialize by node type
8541 FCL (Expressions (E1), Expressions (E2))
8543 FCL (Component_Associations (E1),
8544 Component_Associations (E2));
8547 if Nkind (Expression (E1)) = N_Qualified_Expression
8549 Nkind (Expression (E2)) = N_Qualified_Expression
8551 return FCE (Expression (E1), Expression (E2));
8553 -- Check that the subtype marks and any constraints
8558 Indic1 : constant Node_Id := Expression (E1);
8559 Indic2 : constant Node_Id := Expression (E2);
8564 if Nkind (Indic1) /= N_Subtype_Indication then
8566 Nkind (Indic2) /= N_Subtype_Indication
8567 and then Entity (Indic1) = Entity (Indic2);
8569 elsif Nkind (Indic2) /= N_Subtype_Indication then
8571 Nkind (Indic1) /= N_Subtype_Indication
8572 and then Entity (Indic1) = Entity (Indic2);
8575 if Entity (Subtype_Mark (Indic1)) /=
8576 Entity (Subtype_Mark (Indic2))
8581 Elt1 := First (Constraints (Constraint (Indic1)));
8582 Elt2 := First (Constraints (Constraint (Indic2)));
8583 while Present (Elt1) and then Present (Elt2) loop
8584 if not FCE (Elt1, Elt2) then
8597 when N_Attribute_Reference =>
8599 Attribute_Name (E1) = Attribute_Name (E2)
8600 and then FCL (Expressions (E1), Expressions (E2));
8604 Entity (E1) = Entity (E2)
8605 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
8606 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
8608 when N_Short_Circuit | N_Membership_Test =>
8610 FCE (Left_Opnd (E1), Left_Opnd (E2))
8612 FCE (Right_Opnd (E1), Right_Opnd (E2));
8614 when N_Case_Expression =>
8620 if not FCE (Expression (E1), Expression (E2)) then
8624 Alt1 := First (Alternatives (E1));
8625 Alt2 := First (Alternatives (E2));
8627 if Present (Alt1) /= Present (Alt2) then
8629 elsif No (Alt1) then
8633 if not FCE (Expression (Alt1), Expression (Alt2))
8634 or else not FCL (Discrete_Choices (Alt1),
8635 Discrete_Choices (Alt2))
8646 when N_Character_Literal =>
8648 Char_Literal_Value (E1) = Char_Literal_Value (E2);
8650 when N_Component_Association =>
8652 FCL (Choices (E1), Choices (E2))
8654 FCE (Expression (E1), Expression (E2));
8656 when N_Explicit_Dereference =>
8658 FCE (Prefix (E1), Prefix (E2));
8660 when N_Extension_Aggregate =>
8662 FCL (Expressions (E1), Expressions (E2))
8663 and then Null_Record_Present (E1) =
8664 Null_Record_Present (E2)
8665 and then FCL (Component_Associations (E1),
8666 Component_Associations (E2));
8668 when N_Function_Call =>
8670 FCE (Name (E1), Name (E2))
8672 FCL (Parameter_Associations (E1),
8673 Parameter_Associations (E2));
8675 when N_If_Expression =>
8677 FCL (Expressions (E1), Expressions (E2));
8679 when N_Indexed_Component =>
8681 FCE (Prefix (E1), Prefix (E2))
8683 FCL (Expressions (E1), Expressions (E2));
8685 when N_Integer_Literal =>
8686 return (Intval (E1) = Intval (E2));
8691 when N_Operator_Symbol =>
8693 Chars (E1) = Chars (E2);
8695 when N_Others_Choice =>
8698 when N_Parameter_Association =>
8700 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
8701 and then FCE (Explicit_Actual_Parameter (E1),
8702 Explicit_Actual_Parameter (E2));
8704 when N_Qualified_Expression =>
8706 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
8708 FCE (Expression (E1), Expression (E2));
8710 when N_Quantified_Expression =>
8711 if not FCE (Condition (E1), Condition (E2)) then
8715 if Present (Loop_Parameter_Specification (E1))
8716 and then Present (Loop_Parameter_Specification (E2))
8719 L1 : constant Node_Id :=
8720 Loop_Parameter_Specification (E1);
8721 L2 : constant Node_Id :=
8722 Loop_Parameter_Specification (E2);
8726 Reverse_Present (L1) = Reverse_Present (L2)
8728 FCE (Defining_Identifier (L1),
8729 Defining_Identifier (L2))
8731 FCE (Discrete_Subtype_Definition (L1),
8732 Discrete_Subtype_Definition (L2));
8735 elsif Present (Iterator_Specification (E1))
8736 and then Present (Iterator_Specification (E2))
8739 I1 : constant Node_Id := Iterator_Specification (E1);
8740 I2 : constant Node_Id := Iterator_Specification (E2);
8744 FCE (Defining_Identifier (I1),
8745 Defining_Identifier (I2))
8747 Of_Present (I1) = Of_Present (I2)
8749 Reverse_Present (I1) = Reverse_Present (I2)
8750 and then FCE (Name (I1), Name (I2))
8751 and then FCE (Subtype_Indication (I1),
8752 Subtype_Indication (I2));
8755 -- The quantified expressions used different specifications to
8756 -- walk their respective ranges.
8764 FCE (Low_Bound (E1), Low_Bound (E2))
8766 FCE (High_Bound (E1), High_Bound (E2));
8768 when N_Real_Literal =>
8769 return (Realval (E1) = Realval (E2));
8771 when N_Selected_Component =>
8773 FCE (Prefix (E1), Prefix (E2))
8775 FCE (Selector_Name (E1), Selector_Name (E2));
8779 FCE (Prefix (E1), Prefix (E2))
8781 FCE (Discrete_Range (E1), Discrete_Range (E2));
8783 when N_String_Literal =>
8785 S1 : constant String_Id := Strval (E1);
8786 S2 : constant String_Id := Strval (E2);
8787 L1 : constant Nat := String_Length (S1);
8788 L2 : constant Nat := String_Length (S2);
8795 for J in 1 .. L1 loop
8796 if Get_String_Char (S1, J) /=
8797 Get_String_Char (S2, J)
8807 when N_Type_Conversion =>
8809 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
8811 FCE (Expression (E1), Expression (E2));
8815 Entity (E1) = Entity (E2)
8817 FCE (Right_Opnd (E1), Right_Opnd (E2));
8819 when N_Unchecked_Type_Conversion =>
8821 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
8823 FCE (Expression (E1), Expression (E2));
8825 -- All other node types cannot appear in this context. Strictly
8826 -- we should raise a fatal internal error. Instead we just ignore
8827 -- the nodes. This means that if anyone makes a mistake in the
8828 -- expander and mucks an expression tree irretrievably, the result
8829 -- will be a failure to detect a (probably very obscure) case
8830 -- of non-conformance, which is better than bombing on some
8831 -- case where two expressions do in fact conform.
8838 end Fully_Conformant_Expressions;
8840 ----------------------------------------
8841 -- Fully_Conformant_Discrete_Subtypes --
8842 ----------------------------------------
8844 function Fully_Conformant_Discrete_Subtypes
8845 (Given_S1 : Node_Id;
8846 Given_S2 : Node_Id) return Boolean
8848 S1 : constant Node_Id := Original_Node (Given_S1);
8849 S2 : constant Node_Id := Original_Node (Given_S2);
8851 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
8852 -- Special-case for a bound given by a discriminant, which in the body
8853 -- is replaced with the discriminal of the enclosing type.
8855 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
8856 -- Check both bounds
8858 -----------------------
8859 -- Conforming_Bounds --
8860 -----------------------
8862 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
8864 if Is_Entity_Name (B1)
8865 and then Is_Entity_Name (B2)
8866 and then Ekind (Entity (B1)) = E_Discriminant
8868 return Chars (B1) = Chars (B2);
8871 return Fully_Conformant_Expressions (B1, B2);
8873 end Conforming_Bounds;
8875 -----------------------
8876 -- Conforming_Ranges --
8877 -----------------------
8879 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
8882 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
8884 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
8885 end Conforming_Ranges;
8887 -- Start of processing for Fully_Conformant_Discrete_Subtypes
8890 if Nkind (S1) /= Nkind (S2) then
8893 elsif Is_Entity_Name (S1) then
8894 return Entity (S1) = Entity (S2);
8896 elsif Nkind (S1) = N_Range then
8897 return Conforming_Ranges (S1, S2);
8899 elsif Nkind (S1) = N_Subtype_Indication then
8901 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
8904 (Range_Expression (Constraint (S1)),
8905 Range_Expression (Constraint (S2)));
8909 end Fully_Conformant_Discrete_Subtypes;
8911 --------------------
8912 -- Install_Entity --
8913 --------------------
8915 procedure Install_Entity (E : Entity_Id) is
8916 Prev : constant Entity_Id := Current_Entity (E);
8918 Set_Is_Immediately_Visible (E);
8919 Set_Current_Entity (E);
8920 Set_Homonym (E, Prev);
8923 ---------------------
8924 -- Install_Formals --
8925 ---------------------
8927 procedure Install_Formals (Id : Entity_Id) is
8930 F := First_Formal (Id);
8931 while Present (F) loop
8935 end Install_Formals;
8937 -----------------------------
8938 -- Is_Interface_Conformant --
8939 -----------------------------
8941 function Is_Interface_Conformant
8942 (Tagged_Type : Entity_Id;
8943 Iface_Prim : Entity_Id;
8944 Prim : Entity_Id) return Boolean
8946 -- The operation may in fact be an inherited (implicit) operation
8947 -- rather than the original interface primitive, so retrieve the
8948 -- ultimate ancestor.
8950 Iface : constant Entity_Id :=
8951 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
8952 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
8954 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
8955 -- Return the controlling formal of Prim
8957 ------------------------
8958 -- Controlling_Formal --
8959 ------------------------
8961 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
8965 E := First_Entity (Prim);
8966 while Present (E) loop
8967 if Is_Formal (E) and then Is_Controlling_Formal (E) then
8975 end Controlling_Formal;
8979 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
8980 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
8982 -- Start of processing for Is_Interface_Conformant
8985 pragma Assert (Is_Subprogram (Iface_Prim)
8986 and then Is_Subprogram (Prim)
8987 and then Is_Dispatching_Operation (Iface_Prim)
8988 and then Is_Dispatching_Operation (Prim));
8990 pragma Assert (Is_Interface (Iface)
8991 or else (Present (Alias (Iface_Prim))
8994 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
8996 if Prim = Iface_Prim
8997 or else not Is_Subprogram (Prim)
8998 or else Ekind (Prim) /= Ekind (Iface_Prim)
8999 or else not Is_Dispatching_Operation (Prim)
9000 or else Scope (Prim) /= Scope (Tagged_Type)
9002 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9003 or else not Primitive_Names_Match (Iface_Prim, Prim)
9007 -- The mode of the controlling formals must match
9009 elsif Present (Iface_Ctrl_F)
9010 and then Present (Prim_Ctrl_F)
9011 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9015 -- Case of a procedure, or a function whose result type matches the
9016 -- result type of the interface primitive, or a function that has no
9017 -- controlling result (I or access I).
9019 elsif Ekind (Iface_Prim) = E_Procedure
9020 or else Etype (Prim) = Etype (Iface_Prim)
9021 or else not Has_Controlling_Result (Prim)
9023 return Type_Conformant
9024 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9026 -- Case of a function returning an interface, or an access to one. Check
9027 -- that the return types correspond.
9029 elsif Implements_Interface (Typ, Iface) then
9030 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9032 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9037 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9038 Skip_Controlling_Formals => True);
9044 end Is_Interface_Conformant;
9046 ---------------------------------
9047 -- Is_Non_Overriding_Operation --
9048 ---------------------------------
9050 function Is_Non_Overriding_Operation
9051 (Prev_E : Entity_Id;
9052 New_E : Entity_Id) return Boolean
9056 G_Typ : Entity_Id := Empty;
9058 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9059 -- If F_Type is a derived type associated with a generic actual subtype,
9060 -- then return its Generic_Parent_Type attribute, else return Empty.
9062 function Types_Correspond
9063 (P_Type : Entity_Id;
9064 N_Type : Entity_Id) return Boolean;
9065 -- Returns true if and only if the types (or designated types in the
9066 -- case of anonymous access types) are the same or N_Type is derived
9067 -- directly or indirectly from P_Type.
9069 -----------------------------
9070 -- Get_Generic_Parent_Type --
9071 -----------------------------
9073 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9079 if Is_Derived_Type (F_Typ)
9080 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9082 -- The tree must be traversed to determine the parent subtype in
9083 -- the generic unit, which unfortunately isn't always available
9084 -- via semantic attributes. ??? (Note: The use of Original_Node
9085 -- is needed for cases where a full derived type has been
9088 -- If the parent type is a scalar type, the derivation creates
9089 -- an anonymous base type for it, and the source type is its
9092 if Is_Scalar_Type (F_Typ)
9093 and then not Comes_From_Source (F_Typ)
9097 (Original_Node (Parent (First_Subtype (F_Typ))));
9099 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9101 if Nkind (Defn) = N_Derived_Type_Definition then
9102 Indic := Subtype_Indication (Defn);
9104 if Nkind (Indic) = N_Subtype_Indication then
9105 G_Typ := Entity (Subtype_Mark (Indic));
9107 G_Typ := Entity (Indic);
9110 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9111 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9113 return Generic_Parent_Type (Parent (G_Typ));
9119 end Get_Generic_Parent_Type;
9121 ----------------------
9122 -- Types_Correspond --
9123 ----------------------
9125 function Types_Correspond
9126 (P_Type : Entity_Id;
9127 N_Type : Entity_Id) return Boolean
9129 Prev_Type : Entity_Id := Base_Type (P_Type);
9130 New_Type : Entity_Id := Base_Type (N_Type);
9133 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9134 Prev_Type := Designated_Type (Prev_Type);
9137 if Ekind (New_Type) = E_Anonymous_Access_Type then
9138 New_Type := Designated_Type (New_Type);
9141 if Prev_Type = New_Type then
9144 elsif not Is_Class_Wide_Type (New_Type) then
9145 while Etype (New_Type) /= New_Type loop
9146 New_Type := Etype (New_Type);
9148 if New_Type = Prev_Type then
9154 end Types_Correspond;
9156 -- Start of processing for Is_Non_Overriding_Operation
9159 -- In the case where both operations are implicit derived subprograms
9160 -- then neither overrides the other. This can only occur in certain
9161 -- obscure cases (e.g., derivation from homographs created in a generic
9164 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9167 elsif Ekind (Current_Scope) = E_Package
9168 and then Is_Generic_Instance (Current_Scope)
9169 and then In_Private_Part (Current_Scope)
9170 and then Comes_From_Source (New_E)
9172 -- We examine the formals and result type of the inherited operation,
9173 -- to determine whether their type is derived from (the instance of)
9174 -- a generic type. The first such formal or result type is the one
9177 Formal := First_Formal (Prev_E);
9179 while Present (Formal) loop
9180 F_Typ := Base_Type (Etype (Formal));
9182 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9183 F_Typ := Designated_Type (F_Typ);
9186 G_Typ := Get_Generic_Parent_Type (F_Typ);
9187 exit when Present (G_Typ);
9189 Next_Formal (Formal);
9192 -- If the function dispatches on result check the result type
9194 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9195 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9202 -- If the generic type is a private type, then the original operation
9203 -- was not overriding in the generic, because there was no primitive
9204 -- operation to override.
9206 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9207 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9208 N_Formal_Private_Type_Definition
9212 -- The generic parent type is the ancestor of a formal derived
9213 -- type declaration. We need to check whether it has a primitive
9214 -- operation that should be overridden by New_E in the generic.
9218 P_Formal : Entity_Id;
9219 N_Formal : Entity_Id;
9223 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9226 while Present (Prim_Elt) loop
9227 P_Prim := Node (Prim_Elt);
9229 if Chars (P_Prim) = Chars (New_E)
9230 and then Ekind (P_Prim) = Ekind (New_E)
9232 P_Formal := First_Formal (P_Prim);
9233 N_Formal := First_Formal (New_E);
9234 while Present (P_Formal) and then Present (N_Formal) loop
9235 P_Typ := Etype (P_Formal);
9236 N_Typ := Etype (N_Formal);
9238 if not Types_Correspond (P_Typ, N_Typ) then
9242 Next_Entity (P_Formal);
9243 Next_Entity (N_Formal);
9246 -- Found a matching primitive operation belonging to the
9247 -- formal ancestor type, so the new subprogram is
9251 and then No (N_Formal)
9252 and then (Ekind (New_E) /= E_Function
9255 (Etype (P_Prim), Etype (New_E)))
9261 Next_Elmt (Prim_Elt);
9264 -- If no match found, then the new subprogram does not override
9265 -- in the generic (nor in the instance).
9267 -- If the type in question is not abstract, and the subprogram
9268 -- is, this will be an error if the new operation is in the
9269 -- private part of the instance. Emit a warning now, which will
9270 -- make the subsequent error message easier to understand.
9272 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9273 and then Is_Abstract_Subprogram (Prev_E)
9274 and then In_Private_Part (Current_Scope)
9276 Error_Msg_Node_2 := F_Typ;
9278 ("private operation& in generic unit does not override "
9279 & "any primitive operation of& (RM 12.3 (18))??",
9289 end Is_Non_Overriding_Operation;
9291 -------------------------------------
9292 -- List_Inherited_Pre_Post_Aspects --
9293 -------------------------------------
9295 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9297 if Opt.List_Inherited_Aspects
9298 and then Is_Subprogram_Or_Generic_Subprogram (E)
9301 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9306 for Index in Subps'Range loop
9307 Items := Contract (Subps (Index));
9309 if Present (Items) then
9310 Prag := Pre_Post_Conditions (Items);
9311 while Present (Prag) loop
9312 Error_Msg_Sloc := Sloc (Prag);
9314 if Class_Present (Prag)
9315 and then not Split_PPC (Prag)
9317 if Pragma_Name (Prag) = Name_Precondition then
9319 ("info: & inherits `Pre''Class` aspect from "
9323 ("info: & inherits `Post''Class` aspect from "
9328 Prag := Next_Pragma (Prag);
9334 end List_Inherited_Pre_Post_Aspects;
9336 ------------------------------
9337 -- Make_Inequality_Operator --
9338 ------------------------------
9340 -- S is the defining identifier of an equality operator. We build a
9341 -- subprogram declaration with the right signature. This operation is
9342 -- intrinsic, because it is always expanded as the negation of the
9343 -- call to the equality function.
9345 procedure Make_Inequality_Operator (S : Entity_Id) is
9346 Loc : constant Source_Ptr := Sloc (S);
9349 Op_Name : Entity_Id;
9351 FF : constant Entity_Id := First_Formal (S);
9352 NF : constant Entity_Id := Next_Formal (FF);
9355 -- Check that equality was properly defined, ignore call if not
9362 A : constant Entity_Id :=
9363 Make_Defining_Identifier (Sloc (FF),
9364 Chars => Chars (FF));
9366 B : constant Entity_Id :=
9367 Make_Defining_Identifier (Sloc (NF),
9368 Chars => Chars (NF));
9371 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9373 Formals := New_List (
9374 Make_Parameter_Specification (Loc,
9375 Defining_Identifier => A,
9377 New_Occurrence_Of (Etype (First_Formal (S)),
9378 Sloc (Etype (First_Formal (S))))),
9380 Make_Parameter_Specification (Loc,
9381 Defining_Identifier => B,
9383 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9384 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9387 Make_Subprogram_Declaration (Loc,
9389 Make_Function_Specification (Loc,
9390 Defining_Unit_Name => Op_Name,
9391 Parameter_Specifications => Formals,
9392 Result_Definition =>
9393 New_Occurrence_Of (Standard_Boolean, Loc)));
9395 -- Insert inequality right after equality if it is explicit or after
9396 -- the derived type when implicit. These entities are created only
9397 -- for visibility purposes, and eventually replaced in the course
9398 -- of expansion, so they do not need to be attached to the tree and
9399 -- seen by the back-end. Keeping them internal also avoids spurious
9400 -- freezing problems. The declaration is inserted in the tree for
9401 -- analysis, and removed afterwards. If the equality operator comes
9402 -- from an explicit declaration, attach the inequality immediately
9403 -- after. Else the equality is inherited from a derived type
9404 -- declaration, so insert inequality after that declaration.
9406 if No (Alias (S)) then
9407 Insert_After (Unit_Declaration_Node (S), Decl);
9408 elsif Is_List_Member (Parent (S)) then
9409 Insert_After (Parent (S), Decl);
9411 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9414 Mark_Rewrite_Insertion (Decl);
9415 Set_Is_Intrinsic_Subprogram (Op_Name);
9418 Set_Has_Completion (Op_Name);
9419 Set_Corresponding_Equality (Op_Name, S);
9420 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9422 end Make_Inequality_Operator;
9424 ----------------------
9425 -- May_Need_Actuals --
9426 ----------------------
9428 procedure May_Need_Actuals (Fun : Entity_Id) is
9433 F := First_Formal (Fun);
9435 while Present (F) loop
9436 if No (Default_Value (F)) then
9444 Set_Needs_No_Actuals (Fun, B);
9445 end May_Need_Actuals;
9447 ---------------------
9448 -- Mode_Conformant --
9449 ---------------------
9451 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9454 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9456 end Mode_Conformant;
9458 ---------------------------
9459 -- New_Overloaded_Entity --
9460 ---------------------------
9462 procedure New_Overloaded_Entity
9464 Derived_Type : Entity_Id := Empty)
9466 Overridden_Subp : Entity_Id := Empty;
9467 -- Set if the current scope has an operation that is type-conformant
9468 -- with S, and becomes hidden by S.
9470 Is_Primitive_Subp : Boolean;
9471 -- Set to True if the new subprogram is primitive
9474 -- Entity that S overrides
9476 Prev_Vis : Entity_Id := Empty;
9477 -- Predecessor of E in Homonym chain
9479 procedure Check_For_Primitive_Subprogram
9480 (Is_Primitive : out Boolean;
9481 Is_Overriding : Boolean := False);
9482 -- If the subprogram being analyzed is a primitive operation of the type
9483 -- of a formal or result, set the Has_Primitive_Operations flag on the
9484 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9485 -- corresponding flag on the entity itself for later use.
9487 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9488 -- True if a) E is a subprogram whose first formal is a concurrent type
9489 -- defined in the scope of E that has some entry or subprogram whose
9490 -- profile matches E, or b) E is an internally built dispatching
9491 -- subprogram of a protected type and there is a matching subprogram
9492 -- defined in the enclosing scope of the protected type, or c) E is
9493 -- an entry of a synchronized type and a matching procedure has been
9494 -- previously defined in the enclosing scope of the synchronized type.
9496 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9497 -- Check that E is declared in the private part of the current package,
9498 -- or in the package body, where it may hide a previous declaration.
9499 -- We can't use In_Private_Part by itself because this flag is also
9500 -- set when freezing entities, so we must examine the place of the
9501 -- declaration in the tree, and recognize wrapper packages as well.
9503 function Is_Overriding_Alias
9505 New_E : Entity_Id) return Boolean;
9506 -- Check whether new subprogram and old subprogram are both inherited
9507 -- from subprograms that have distinct dispatch table entries. This can
9508 -- occur with derivations from instances with accidental homonyms. The
9509 -- function is conservative given that the converse is only true within
9510 -- instances that contain accidental overloadings.
9512 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9513 -- Report conflict between entities S and E
9515 ------------------------------------
9516 -- Check_For_Primitive_Subprogram --
9517 ------------------------------------
9519 procedure Check_For_Primitive_Subprogram
9520 (Is_Primitive : out Boolean;
9521 Is_Overriding : Boolean := False)
9527 function Visible_Part_Type (T : Entity_Id) return Boolean;
9528 -- Returns true if T is declared in the visible part of the current
9529 -- package scope; otherwise returns false. Assumes that T is declared
9532 procedure Check_Private_Overriding (T : Entity_Id);
9533 -- Checks that if a primitive abstract subprogram of a visible
9534 -- abstract type is declared in a private part, then it must override
9535 -- an abstract subprogram declared in the visible part. Also checks
9536 -- that if a primitive function with a controlling result is declared
9537 -- in a private part, then it must override a function declared in
9538 -- the visible part.
9540 ------------------------------
9541 -- Check_Private_Overriding --
9542 ------------------------------
9544 procedure Check_Private_Overriding (T : Entity_Id) is
9545 function Overrides_Private_Part_Op return Boolean;
9546 -- This detects the special case where the overriding subprogram
9547 -- is overriding a subprogram that was declared in the same
9548 -- private part. That case is illegal by 3.9.3(10).
9550 function Overrides_Visible_Function
9551 (Partial_View : Entity_Id) return Boolean;
9552 -- True if S overrides a function in the visible part. The
9553 -- overridden function could be explicitly or implicitly declared.
9555 -------------------------------
9556 -- Overrides_Private_Part_Op --
9557 -------------------------------
9559 function Overrides_Private_Part_Op return Boolean is
9560 Over_Decl : constant Node_Id :=
9561 Unit_Declaration_Node (Overridden_Operation (S));
9562 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
9565 pragma Assert (Is_Overriding);
9567 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
9569 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
9571 return In_Same_List (Over_Decl, Subp_Decl);
9572 end Overrides_Private_Part_Op;
9574 --------------------------------
9575 -- Overrides_Visible_Function --
9576 --------------------------------
9578 function Overrides_Visible_Function
9579 (Partial_View : Entity_Id) return Boolean
9582 if not Is_Overriding or else not Has_Homonym (S) then
9586 if not Present (Partial_View) then
9590 -- Search through all the homonyms H of S in the current
9591 -- package spec, and return True if we find one that matches.
9592 -- Note that Parent (H) will be the declaration of the
9593 -- partial view of T for a match.
9600 exit when not Present (H) or else Scope (H) /= Scope (S);
9604 N_Private_Extension_Declaration,
9605 N_Private_Type_Declaration)
9606 and then Defining_Identifier (Parent (H)) = Partial_View
9614 end Overrides_Visible_Function;
9616 -- Start of processing for Check_Private_Overriding
9619 if Is_Package_Or_Generic_Package (Current_Scope)
9620 and then In_Private_Part (Current_Scope)
9621 and then Visible_Part_Type (T)
9622 and then not In_Instance
9624 if Is_Abstract_Type (T)
9625 and then Is_Abstract_Subprogram (S)
9626 and then (not Is_Overriding
9627 or else not Is_Abstract_Subprogram (E)
9628 or else Overrides_Private_Part_Op)
9631 ("abstract subprograms must be visible (RM 3.9.3(10))!",
9634 elsif Ekind (S) = E_Function then
9636 Partial_View : constant Entity_Id :=
9637 Incomplete_Or_Partial_View (T);
9640 if not Overrides_Visible_Function (Partial_View) then
9642 -- Here, S is "function ... return T;" declared in
9643 -- the private part, not overriding some visible
9644 -- operation. That's illegal in the tagged case
9645 -- (but not if the private type is untagged).
9647 if ((Present (Partial_View)
9648 and then Is_Tagged_Type (Partial_View))
9649 or else (not Present (Partial_View)
9650 and then Is_Tagged_Type (T)))
9651 and then T = Base_Type (Etype (S))
9654 ("private function with tagged result must"
9655 & " override visible-part function", S);
9657 ("\move subprogram to the visible part"
9658 & " (RM 3.9.3(10))", S);
9660 -- AI05-0073: extend this test to the case of a
9661 -- function with a controlling access result.
9663 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
9664 and then Is_Tagged_Type (Designated_Type (Etype (S)))
9666 not Is_Class_Wide_Type
9667 (Designated_Type (Etype (S)))
9668 and then Ada_Version >= Ada_2012
9671 ("private function with controlling access "
9672 & "result must override visible-part function",
9675 ("\move subprogram to the visible part"
9676 & " (RM 3.9.3(10))", S);
9682 end Check_Private_Overriding;
9684 -----------------------
9685 -- Visible_Part_Type --
9686 -----------------------
9688 function Visible_Part_Type (T : Entity_Id) return Boolean is
9689 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
9693 -- If the entity is a private type, then it must be declared in a
9696 if Ekind (T) in Private_Kind then
9700 -- Otherwise, we traverse the visible part looking for its
9701 -- corresponding declaration. We cannot use the declaration
9702 -- node directly because in the private part the entity of a
9703 -- private type is the one in the full view, which does not
9704 -- indicate that it is the completion of something visible.
9706 N := First (Visible_Declarations (Specification (P)));
9707 while Present (N) loop
9708 if Nkind (N) = N_Full_Type_Declaration
9709 and then Present (Defining_Identifier (N))
9710 and then T = Defining_Identifier (N)
9714 elsif Nkind_In (N, N_Private_Type_Declaration,
9715 N_Private_Extension_Declaration)
9716 and then Present (Defining_Identifier (N))
9717 and then T = Full_View (Defining_Identifier (N))
9726 end Visible_Part_Type;
9728 -- Start of processing for Check_For_Primitive_Subprogram
9731 Is_Primitive := False;
9733 if not Comes_From_Source (S) then
9736 -- If subprogram is at library level, it is not primitive operation
9738 elsif Current_Scope = Standard_Standard then
9741 elsif (Is_Package_Or_Generic_Package (Current_Scope)
9742 and then not In_Package_Body (Current_Scope))
9743 or else Is_Overriding
9745 -- For function, check return type
9747 if Ekind (S) = E_Function then
9748 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
9749 F_Typ := Designated_Type (Etype (S));
9754 B_Typ := Base_Type (F_Typ);
9756 if Scope (B_Typ) = Current_Scope
9757 and then not Is_Class_Wide_Type (B_Typ)
9758 and then not Is_Generic_Type (B_Typ)
9760 Is_Primitive := True;
9761 Set_Has_Primitive_Operations (B_Typ);
9762 Set_Is_Primitive (S);
9763 Check_Private_Overriding (B_Typ);
9765 -- The Ghost policy in effect at the point of declaration of
9766 -- a tagged type and a primitive operation must match
9767 -- (SPARK RM 6.9(16)).
9769 Check_Ghost_Primitive (S, B_Typ);
9773 -- For all subprograms, check formals
9775 Formal := First_Formal (S);
9776 while Present (Formal) loop
9777 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
9778 F_Typ := Designated_Type (Etype (Formal));
9780 F_Typ := Etype (Formal);
9783 B_Typ := Base_Type (F_Typ);
9785 if Ekind (B_Typ) = E_Access_Subtype then
9786 B_Typ := Base_Type (B_Typ);
9789 if Scope (B_Typ) = Current_Scope
9790 and then not Is_Class_Wide_Type (B_Typ)
9791 and then not Is_Generic_Type (B_Typ)
9793 Is_Primitive := True;
9794 Set_Is_Primitive (S);
9795 Set_Has_Primitive_Operations (B_Typ);
9796 Check_Private_Overriding (B_Typ);
9798 -- The Ghost policy in effect at the point of declaration of
9799 -- a tagged type and a primitive operation must match
9800 -- (SPARK RM 6.9(16)).
9802 Check_Ghost_Primitive (S, B_Typ);
9805 Next_Formal (Formal);
9808 -- Special case: An equality function can be redefined for a type
9809 -- occurring in a declarative part, and won't otherwise be treated as
9810 -- a primitive because it doesn't occur in a package spec and doesn't
9811 -- override an inherited subprogram. It's important that we mark it
9812 -- primitive so it can be returned by Collect_Primitive_Operations
9813 -- and be used in composing the equality operation of later types
9814 -- that have a component of the type.
9816 elsif Chars (S) = Name_Op_Eq
9817 and then Etype (S) = Standard_Boolean
9819 B_Typ := Base_Type (Etype (First_Formal (S)));
9821 if Scope (B_Typ) = Current_Scope
9823 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
9824 and then not Is_Limited_Type (B_Typ)
9826 Is_Primitive := True;
9827 Set_Is_Primitive (S);
9828 Set_Has_Primitive_Operations (B_Typ);
9829 Check_Private_Overriding (B_Typ);
9831 -- The Ghost policy in effect at the point of declaration of a
9832 -- tagged type and a primitive operation must match
9833 -- (SPARK RM 6.9(16)).
9835 Check_Ghost_Primitive (S, B_Typ);
9838 end Check_For_Primitive_Subprogram;
9840 --------------------------------------
9841 -- Has_Matching_Entry_Or_Subprogram --
9842 --------------------------------------
9844 function Has_Matching_Entry_Or_Subprogram
9845 (E : Entity_Id) return Boolean
9847 function Check_Conforming_Parameters
9848 (E1_Param : Node_Id;
9849 E2_Param : Node_Id) return Boolean;
9850 -- Starting from the given parameters, check that all the parameters
9851 -- of two entries or subprograms are subtype conformant. Used to skip
9852 -- the check on the controlling argument.
9854 function Matching_Entry_Or_Subprogram
9855 (Conc_Typ : Entity_Id;
9856 Subp : Entity_Id) return Entity_Id;
9857 -- Return the first entry or subprogram of the given concurrent type
9858 -- whose name matches the name of Subp and has a profile conformant
9859 -- with Subp; return Empty if not found.
9861 function Matching_Dispatching_Subprogram
9862 (Conc_Typ : Entity_Id;
9863 Ent : Entity_Id) return Entity_Id;
9864 -- Return the first dispatching primitive of Conc_Type defined in the
9865 -- enclosing scope of Conc_Type (i.e. before the full definition of
9866 -- this concurrent type) whose name matches the entry Ent and has a
9867 -- profile conformant with the profile of the corresponding (not yet
9868 -- built) dispatching primitive of Ent; return Empty if not found.
9870 function Matching_Original_Protected_Subprogram
9871 (Prot_Typ : Entity_Id;
9872 Subp : Entity_Id) return Entity_Id;
9873 -- Return the first subprogram defined in the enclosing scope of
9874 -- Prot_Typ (before the full definition of this protected type)
9875 -- whose name matches the original name of Subp and has a profile
9876 -- conformant with the profile of Subp; return Empty if not found.
9878 ---------------------------------
9879 -- Check_Confirming_Parameters --
9880 ---------------------------------
9882 function Check_Conforming_Parameters
9883 (E1_Param : Node_Id;
9884 E2_Param : Node_Id) return Boolean
9886 Param_E1 : Node_Id := E1_Param;
9887 Param_E2 : Node_Id := E2_Param;
9890 while Present (Param_E1) and then Present (Param_E2) loop
9891 if Ekind (Defining_Identifier (Param_E1)) /=
9892 Ekind (Defining_Identifier (Param_E2))
9895 (Find_Parameter_Type (Param_E1),
9896 Find_Parameter_Type (Param_E2),
9906 -- The candidate is not valid if one of the two lists contains
9907 -- more parameters than the other
9909 return No (Param_E1) and then No (Param_E2);
9910 end Check_Conforming_Parameters;
9912 ----------------------------------
9913 -- Matching_Entry_Or_Subprogram --
9914 ----------------------------------
9916 function Matching_Entry_Or_Subprogram
9917 (Conc_Typ : Entity_Id;
9918 Subp : Entity_Id) return Entity_Id
9923 E := First_Entity (Conc_Typ);
9924 while Present (E) loop
9925 if Chars (Subp) = Chars (E)
9926 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
9928 Check_Conforming_Parameters
9929 (First (Parameter_Specifications (Parent (E))),
9930 Next (First (Parameter_Specifications (Parent (Subp)))))
9939 end Matching_Entry_Or_Subprogram;
9941 -------------------------------------
9942 -- Matching_Dispatching_Subprogram --
9943 -------------------------------------
9945 function Matching_Dispatching_Subprogram
9946 (Conc_Typ : Entity_Id;
9947 Ent : Entity_Id) return Entity_Id
9952 -- Search for entities in the enclosing scope of this synchonized
9955 pragma Assert (Is_Concurrent_Type (Conc_Typ));
9956 Push_Scope (Scope (Conc_Typ));
9957 E := Current_Entity_In_Scope (Ent);
9960 while Present (E) loop
9961 if Scope (E) = Scope (Conc_Typ)
9962 and then Comes_From_Source (E)
9963 and then Ekind (E) = E_Procedure
9964 and then Present (First_Entity (E))
9965 and then Is_Controlling_Formal (First_Entity (E))
9966 and then Etype (First_Entity (E)) = Conc_Typ
9968 Check_Conforming_Parameters
9969 (First (Parameter_Specifications (Parent (Ent))),
9970 Next (First (Parameter_Specifications (Parent (E)))))
9979 end Matching_Dispatching_Subprogram;
9981 --------------------------------------------
9982 -- Matching_Original_Protected_Subprogram --
9983 --------------------------------------------
9985 function Matching_Original_Protected_Subprogram
9986 (Prot_Typ : Entity_Id;
9987 Subp : Entity_Id) return Entity_Id
9989 ICF : constant Boolean :=
9990 Is_Controlling_Formal (First_Entity (Subp));
9994 -- Temporarily decorate the first parameter of Subp as controlling
9995 -- formal, required to invoke Subtype_Conformant.
9997 Set_Is_Controlling_Formal (First_Entity (Subp));
10000 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10002 while Present (E) loop
10003 if Scope (E) = Scope (Prot_Typ)
10004 and then Comes_From_Source (E)
10005 and then Ekind (Subp) = Ekind (E)
10006 and then Present (First_Entity (E))
10007 and then Is_Controlling_Formal (First_Entity (E))
10008 and then Etype (First_Entity (E)) = Prot_Typ
10009 and then Subtype_Conformant (Subp, E,
10010 Skip_Controlling_Formals => True)
10012 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10019 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10022 end Matching_Original_Protected_Subprogram;
10024 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10027 -- Case 1: E is a subprogram whose first formal is a concurrent type
10028 -- defined in the scope of E that has an entry or subprogram whose
10029 -- profile matches E.
10031 if Comes_From_Source (E)
10032 and then Is_Subprogram (E)
10033 and then Present (First_Entity (E))
10034 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10037 Scope (Corresponding_Concurrent_Type
10038 (Etype (First_Entity (E))))
10041 (Matching_Entry_Or_Subprogram
10042 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10045 Report_Conflict (E,
10046 Matching_Entry_Or_Subprogram
10047 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10052 -- Case 2: E is an internally built dispatching subprogram of a
10053 -- protected type and there is a subprogram defined in the enclosing
10054 -- scope of the protected type that has the original name of E and
10055 -- its profile is conformant with the profile of E. We check the
10056 -- name of the original protected subprogram associated with E since
10057 -- the expander builds dispatching primitives of protected functions
10058 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10060 elsif not Comes_From_Source (E)
10061 and then Is_Subprogram (E)
10062 and then Present (First_Entity (E))
10063 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10064 and then Present (Original_Protected_Subprogram (E))
10067 (Matching_Original_Protected_Subprogram
10068 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10071 Report_Conflict (E,
10072 Matching_Original_Protected_Subprogram
10073 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10077 -- Case 3: E is an entry of a synchronized type and a matching
10078 -- procedure has been previously defined in the enclosing scope
10079 -- of the synchronized type.
10081 elsif Comes_From_Source (E)
10082 and then Ekind (E) = E_Entry
10084 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10086 Report_Conflict (E,
10087 Matching_Dispatching_Subprogram (Current_Scope, E));
10092 end Has_Matching_Entry_Or_Subprogram;
10094 ----------------------------
10095 -- Is_Private_Declaration --
10096 ----------------------------
10098 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10099 Decl : constant Node_Id := Unit_Declaration_Node (E);
10100 Priv_Decls : List_Id;
10103 if Is_Package_Or_Generic_Package (Current_Scope)
10104 and then In_Private_Part (Current_Scope)
10107 Private_Declarations (Package_Specification (Current_Scope));
10109 return In_Package_Body (Current_Scope)
10111 (Is_List_Member (Decl)
10112 and then List_Containing (Decl) = Priv_Decls)
10113 or else (Nkind (Parent (Decl)) = N_Package_Specification
10115 Is_Compilation_Unit
10116 (Defining_Entity (Parent (Decl)))
10117 and then List_Containing (Parent (Parent (Decl))) =
10122 end Is_Private_Declaration;
10124 --------------------------
10125 -- Is_Overriding_Alias --
10126 --------------------------
10128 function Is_Overriding_Alias
10129 (Old_E : Entity_Id;
10130 New_E : Entity_Id) return Boolean
10132 AO : constant Entity_Id := Alias (Old_E);
10133 AN : constant Entity_Id := Alias (New_E);
10136 return Scope (AO) /= Scope (AN)
10137 or else No (DTC_Entity (AO))
10138 or else No (DTC_Entity (AN))
10139 or else DT_Position (AO) = DT_Position (AN);
10140 end Is_Overriding_Alias;
10142 ---------------------
10143 -- Report_Conflict --
10144 ---------------------
10146 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10148 Error_Msg_Sloc := Sloc (E);
10150 -- Generate message, with useful additional warning if in generic
10152 if Is_Generic_Unit (E) then
10153 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10154 Error_Msg_N ("\& conflicts with declaration#", S);
10156 Error_Msg_N ("& conflicts with declaration#", S);
10158 end Report_Conflict;
10160 -- Start of processing for New_Overloaded_Entity
10163 -- We need to look for an entity that S may override. This must be a
10164 -- homonym in the current scope, so we look for the first homonym of
10165 -- S in the current scope as the starting point for the search.
10167 E := Current_Entity_In_Scope (S);
10169 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10170 -- They are directly added to the list of primitive operations of
10171 -- Derived_Type, unless this is a rederivation in the private part
10172 -- of an operation that was already derived in the visible part of
10173 -- the current package.
10175 if Ada_Version >= Ada_2005
10176 and then Present (Derived_Type)
10177 and then Present (Alias (S))
10178 and then Is_Dispatching_Operation (Alias (S))
10179 and then Present (Find_Dispatching_Type (Alias (S)))
10180 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10182 -- For private types, when the full-view is processed we propagate to
10183 -- the full view the non-overridden entities whose attribute "alias"
10184 -- references an interface primitive. These entities were added by
10185 -- Derive_Subprograms to ensure that interface primitives are
10188 -- Inside_Freeze_Actions is non zero when S corresponds with an
10189 -- internal entity that links an interface primitive with its
10190 -- covering primitive through attribute Interface_Alias (see
10191 -- Add_Internal_Interface_Entities).
10193 if Inside_Freezing_Actions = 0
10194 and then Is_Package_Or_Generic_Package (Current_Scope)
10195 and then In_Private_Part (Current_Scope)
10196 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10197 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10198 and then Full_View (Defining_Identifier (Parent (E)))
10199 = Defining_Identifier (Parent (S))
10200 and then Alias (E) = Alias (S)
10202 Check_Operation_From_Private_View (S, E);
10203 Set_Is_Dispatching_Operation (S);
10208 Enter_Overloaded_Entity (S);
10209 Check_Dispatching_Operation (S, Empty);
10210 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10216 -- For synchronized types check conflicts of this entity with previously
10217 -- defined entities.
10219 if Ada_Version >= Ada_2005
10220 and then Has_Matching_Entry_Or_Subprogram (S)
10225 -- If there is no homonym then this is definitely not overriding
10228 Enter_Overloaded_Entity (S);
10229 Check_Dispatching_Operation (S, Empty);
10230 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10232 -- If subprogram has an explicit declaration, check whether it has an
10233 -- overriding indicator.
10235 if Comes_From_Source (S) then
10236 Check_Synchronized_Overriding (S, Overridden_Subp);
10238 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10239 -- it may have overridden some hidden inherited primitive. Update
10240 -- Overridden_Subp to avoid spurious errors when checking the
10241 -- overriding indicator.
10243 if Ada_Version >= Ada_2012
10244 and then No (Overridden_Subp)
10245 and then Is_Dispatching_Operation (S)
10246 and then Present (Overridden_Operation (S))
10248 Overridden_Subp := Overridden_Operation (S);
10251 Check_Overriding_Indicator
10252 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10254 -- The Ghost policy in effect at the point of declaration of a
10255 -- parent subprogram and an overriding subprogram must match
10256 -- (SPARK RM 6.9(17)).
10258 Check_Ghost_Overriding (S, Overridden_Subp);
10261 -- If there is a homonym that is not overloadable, then we have an
10262 -- error, except for the special cases checked explicitly below.
10264 elsif not Is_Overloadable (E) then
10266 -- Check for spurious conflict produced by a subprogram that has the
10267 -- same name as that of the enclosing generic package. The conflict
10268 -- occurs within an instance, between the subprogram and the renaming
10269 -- declaration for the package. After the subprogram, the package
10270 -- renaming declaration becomes hidden.
10272 if Ekind (E) = E_Package
10273 and then Present (Renamed_Object (E))
10274 and then Renamed_Object (E) = Current_Scope
10275 and then Nkind (Parent (Renamed_Object (E))) =
10276 N_Package_Specification
10277 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10280 Set_Is_Immediately_Visible (E, False);
10281 Enter_Overloaded_Entity (S);
10282 Set_Homonym (S, Homonym (E));
10283 Check_Dispatching_Operation (S, Empty);
10284 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10286 -- If the subprogram is implicit it is hidden by the previous
10287 -- declaration. However if it is dispatching, it must appear in the
10288 -- dispatch table anyway, because it can be dispatched to even if it
10289 -- cannot be called directly.
10291 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10292 Set_Scope (S, Current_Scope);
10294 if Is_Dispatching_Operation (Alias (S)) then
10295 Check_Dispatching_Operation (S, Empty);
10301 Report_Conflict (S, E);
10305 -- E exists and is overloadable
10308 Check_Synchronized_Overriding (S, Overridden_Subp);
10310 -- Loop through E and its homonyms to determine if any of them is
10311 -- the candidate for overriding by S.
10313 while Present (E) loop
10315 -- Definitely not interesting if not in the current scope
10317 if Scope (E) /= Current_Scope then
10320 -- A function can overload the name of an abstract state. The
10321 -- state can be viewed as a function with a profile that cannot
10322 -- be matched by anything.
10324 elsif Ekind (S) = E_Function
10325 and then Ekind (E) = E_Abstract_State
10327 Enter_Overloaded_Entity (S);
10330 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10331 -- procedures locate the internally generated spec. We enforce
10332 -- mode conformance since a tagged type may inherit from
10333 -- interfaces several null primitives which differ only in
10334 -- the mode of the formals.
10336 elsif not Comes_From_Source (S)
10337 and then Is_Null_Procedure (S)
10338 and then not Mode_Conformant (E, S)
10342 -- Check if we have type conformance
10344 elsif Type_Conformant (E, S) then
10346 -- If the old and new entities have the same profile and one
10347 -- is not the body of the other, then this is an error, unless
10348 -- one of them is implicitly declared.
10350 -- There are some cases when both can be implicit, for example
10351 -- when both a literal and a function that overrides it are
10352 -- inherited in a derivation, or when an inherited operation
10353 -- of a tagged full type overrides the inherited operation of
10354 -- a private extension. Ada 83 had a special rule for the
10355 -- literal case. In Ada 95, the later implicit operation hides
10356 -- the former, and the literal is always the former. In the
10357 -- odd case where both are derived operations declared at the
10358 -- same point, both operations should be declared, and in that
10359 -- case we bypass the following test and proceed to the next
10360 -- part. This can only occur for certain obscure cases in
10361 -- instances, when an operation on a type derived from a formal
10362 -- private type does not override a homograph inherited from
10363 -- the actual. In subsequent derivations of such a type, the
10364 -- DT positions of these operations remain distinct, if they
10367 if Present (Alias (S))
10368 and then (No (Alias (E))
10369 or else Comes_From_Source (E)
10370 or else Is_Abstract_Subprogram (S)
10372 (Is_Dispatching_Operation (E)
10373 and then Is_Overriding_Alias (E, S)))
10374 and then Ekind (E) /= E_Enumeration_Literal
10376 -- When an derived operation is overloaded it may be due to
10377 -- the fact that the full view of a private extension
10378 -- re-inherits. It has to be dealt with.
10380 if Is_Package_Or_Generic_Package (Current_Scope)
10381 and then In_Private_Part (Current_Scope)
10383 Check_Operation_From_Private_View (S, E);
10386 -- In any case the implicit operation remains hidden by the
10387 -- existing declaration, which is overriding. Indicate that
10388 -- E overrides the operation from which S is inherited.
10390 if Present (Alias (S)) then
10391 Set_Overridden_Operation (E, Alias (S));
10392 Inherit_Subprogram_Contract (E, Alias (S));
10395 Set_Overridden_Operation (E, S);
10396 Inherit_Subprogram_Contract (E, S);
10399 if Comes_From_Source (E) then
10400 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10402 -- The Ghost policy in effect at the point of declaration
10403 -- of a parent subprogram and an overriding subprogram
10404 -- must match (SPARK RM 6.9(17)).
10406 Check_Ghost_Overriding (E, S);
10411 -- Within an instance, the renaming declarations for actual
10412 -- subprograms may become ambiguous, but they do not hide each
10415 elsif Ekind (E) /= E_Entry
10416 and then not Comes_From_Source (E)
10417 and then not Is_Generic_Instance (E)
10418 and then (Present (Alias (E))
10419 or else Is_Intrinsic_Subprogram (E))
10420 and then (not In_Instance
10421 or else No (Parent (E))
10422 or else Nkind (Unit_Declaration_Node (E)) /=
10423 N_Subprogram_Renaming_Declaration)
10425 -- A subprogram child unit is not allowed to override an
10426 -- inherited subprogram (10.1.1(20)).
10428 if Is_Child_Unit (S) then
10430 ("child unit overrides inherited subprogram in parent",
10435 if Is_Non_Overriding_Operation (E, S) then
10436 Enter_Overloaded_Entity (S);
10438 if No (Derived_Type)
10439 or else Is_Tagged_Type (Derived_Type)
10441 Check_Dispatching_Operation (S, Empty);
10447 -- E is a derived operation or an internal operator which
10448 -- is being overridden. Remove E from further visibility.
10449 -- Furthermore, if E is a dispatching operation, it must be
10450 -- replaced in the list of primitive operations of its type
10451 -- (see Override_Dispatching_Operation).
10453 Overridden_Subp := E;
10459 Prev := First_Entity (Current_Scope);
10460 while Present (Prev) and then Next_Entity (Prev) /= E loop
10461 Next_Entity (Prev);
10464 -- It is possible for E to be in the current scope and
10465 -- yet not in the entity chain. This can only occur in a
10466 -- generic context where E is an implicit concatenation
10467 -- in the formal part, because in a generic body the
10468 -- entity chain starts with the formals.
10470 -- In GNATprove mode, a wrapper for an operation with
10471 -- axiomatization may be a homonym of another declaration
10472 -- for an actual subprogram (needs refinement ???).
10476 and then GNATprove_Mode
10478 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10479 N_Subprogram_Renaming_Declaration
10483 pragma Assert (Chars (E) = Name_Op_Concat);
10488 -- E must be removed both from the entity_list of the
10489 -- current scope, and from the visibility chain.
10491 if Debug_Flag_E then
10492 Write_Str ("Override implicit operation ");
10493 Write_Int (Int (E));
10497 -- If E is a predefined concatenation, it stands for four
10498 -- different operations. As a result, a single explicit
10499 -- declaration does not hide it. In a possible ambiguous
10500 -- situation, Disambiguate chooses the user-defined op,
10501 -- so it is correct to retain the previous internal one.
10503 if Chars (E) /= Name_Op_Concat
10504 or else Ekind (E) /= E_Operator
10506 -- For nondispatching derived operations that are
10507 -- overridden by a subprogram declared in the private
10508 -- part of a package, we retain the derived subprogram
10509 -- but mark it as not immediately visible. If the
10510 -- derived operation was declared in the visible part
10511 -- then this ensures that it will still be visible
10512 -- outside the package with the proper signature
10513 -- (calls from outside must also be directed to this
10514 -- version rather than the overriding one, unlike the
10515 -- dispatching case). Calls from inside the package
10516 -- will still resolve to the overriding subprogram
10517 -- since the derived one is marked as not visible
10518 -- within the package.
10520 -- If the private operation is dispatching, we achieve
10521 -- the overriding by keeping the implicit operation
10522 -- but setting its alias to be the overriding one. In
10523 -- this fashion the proper body is executed in all
10524 -- cases, but the original signature is used outside
10527 -- If the overriding is not in the private part, we
10528 -- remove the implicit operation altogether.
10530 if Is_Private_Declaration (S) then
10531 if not Is_Dispatching_Operation (E) then
10532 Set_Is_Immediately_Visible (E, False);
10534 -- Work done in Override_Dispatching_Operation,
10535 -- so nothing else needs to be done here.
10541 -- Find predecessor of E in Homonym chain
10543 if E = Current_Entity (E) then
10546 Prev_Vis := Current_Entity (E);
10547 while Homonym (Prev_Vis) /= E loop
10548 Prev_Vis := Homonym (Prev_Vis);
10552 if Prev_Vis /= Empty then
10554 -- Skip E in the visibility chain
10556 Set_Homonym (Prev_Vis, Homonym (E));
10559 Set_Name_Entity_Id (Chars (E), Homonym (E));
10562 Set_Next_Entity (Prev, Next_Entity (E));
10564 if No (Next_Entity (Prev)) then
10565 Set_Last_Entity (Current_Scope, Prev);
10570 Enter_Overloaded_Entity (S);
10572 -- For entities generated by Derive_Subprograms the
10573 -- overridden operation is the inherited primitive
10574 -- (which is available through the attribute alias).
10576 if not (Comes_From_Source (E))
10577 and then Is_Dispatching_Operation (E)
10578 and then Find_Dispatching_Type (E) =
10579 Find_Dispatching_Type (S)
10580 and then Present (Alias (E))
10581 and then Comes_From_Source (Alias (E))
10583 Set_Overridden_Operation (S, Alias (E));
10584 Inherit_Subprogram_Contract (S, Alias (E));
10586 -- Normal case of setting entity as overridden
10588 -- Note: Static_Initialization and Overridden_Operation
10589 -- attributes use the same field in subprogram entities.
10590 -- Static_Initialization is only defined for internal
10591 -- initialization procedures, where Overridden_Operation
10592 -- is irrelevant. Therefore the setting of this attribute
10593 -- must check whether the target is an init_proc.
10595 elsif not Is_Init_Proc (S) then
10596 Set_Overridden_Operation (S, E);
10597 Inherit_Subprogram_Contract (S, E);
10600 Check_Overriding_Indicator (S, E, Is_Primitive => True);
10602 -- The Ghost policy in effect at the point of declaration
10603 -- of a parent subprogram and an overriding subprogram
10604 -- must match (SPARK RM 6.9(17)).
10606 Check_Ghost_Overriding (S, E);
10608 -- If S is a user-defined subprogram or a null procedure
10609 -- expanded to override an inherited null procedure, or a
10610 -- predefined dispatching primitive then indicate that E
10611 -- overrides the operation from which S is inherited.
10613 if Comes_From_Source (S)
10615 (Present (Parent (S))
10617 Nkind (Parent (S)) = N_Procedure_Specification
10619 Null_Present (Parent (S)))
10621 (Present (Alias (E))
10623 Is_Predefined_Dispatching_Operation (Alias (E)))
10625 if Present (Alias (E)) then
10626 Set_Overridden_Operation (S, Alias (E));
10627 Inherit_Subprogram_Contract (S, Alias (E));
10631 if Is_Dispatching_Operation (E) then
10633 -- An overriding dispatching subprogram inherits the
10634 -- convention of the overridden subprogram (AI-117).
10636 Set_Convention (S, Convention (E));
10637 Check_Dispatching_Operation (S, E);
10640 Check_Dispatching_Operation (S, Empty);
10643 Check_For_Primitive_Subprogram
10644 (Is_Primitive_Subp, Is_Overriding => True);
10645 goto Check_Inequality;
10648 -- Apparent redeclarations in instances can occur when two
10649 -- formal types get the same actual type. The subprograms in
10650 -- in the instance are legal, even if not callable from the
10651 -- outside. Calls from within are disambiguated elsewhere.
10652 -- For dispatching operations in the visible part, the usual
10653 -- rules apply, and operations with the same profile are not
10654 -- legal (B830001).
10656 elsif (In_Instance_Visible_Part
10657 and then not Is_Dispatching_Operation (E))
10658 or else In_Instance_Not_Visible
10662 -- Here we have a real error (identical profile)
10665 Error_Msg_Sloc := Sloc (E);
10667 -- Avoid cascaded errors if the entity appears in
10668 -- subsequent calls.
10670 Set_Scope (S, Current_Scope);
10672 -- Generate error, with extra useful warning for the case
10673 -- of a generic instance with no completion.
10675 if Is_Generic_Instance (S)
10676 and then not Has_Completion (E)
10679 ("instantiation cannot provide body for&", S);
10680 Error_Msg_N ("\& conflicts with declaration#", S);
10682 Error_Msg_N ("& conflicts with declaration#", S);
10689 -- If one subprogram has an access parameter and the other
10690 -- a parameter of an access type, calls to either might be
10691 -- ambiguous. Verify that parameters match except for the
10692 -- access parameter.
10694 if May_Hide_Profile then
10700 F1 := First_Formal (S);
10701 F2 := First_Formal (E);
10702 while Present (F1) and then Present (F2) loop
10703 if Is_Access_Type (Etype (F1)) then
10704 if not Is_Access_Type (Etype (F2))
10705 or else not Conforming_Types
10706 (Designated_Type (Etype (F1)),
10707 Designated_Type (Etype (F2)),
10710 May_Hide_Profile := False;
10714 not Conforming_Types
10715 (Etype (F1), Etype (F2), Type_Conformant)
10717 May_Hide_Profile := False;
10724 if May_Hide_Profile
10728 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
10737 -- On exit, we know that S is a new entity
10739 Enter_Overloaded_Entity (S);
10740 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10741 Check_Overriding_Indicator
10742 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10744 -- The Ghost policy in effect at the point of declaration of a parent
10745 -- subprogram and an overriding subprogram must match
10746 -- (SPARK RM 6.9(17)).
10748 Check_Ghost_Overriding (S, Overridden_Subp);
10750 -- Overloading is not allowed in SPARK, except for operators
10752 if Nkind (S) /= N_Defining_Operator_Symbol then
10753 Error_Msg_Sloc := Sloc (Homonym (S));
10754 Check_SPARK_05_Restriction
10755 ("overloading not allowed with entity#", S);
10758 -- If S is a derived operation for an untagged type then by
10759 -- definition it's not a dispatching operation (even if the parent
10760 -- operation was dispatching), so Check_Dispatching_Operation is not
10761 -- called in that case.
10763 if No (Derived_Type)
10764 or else Is_Tagged_Type (Derived_Type)
10766 Check_Dispatching_Operation (S, Empty);
10770 -- If this is a user-defined equality operator that is not a derived
10771 -- subprogram, create the corresponding inequality. If the operation is
10772 -- dispatching, the expansion is done elsewhere, and we do not create
10773 -- an explicit inequality operation.
10775 <<Check_Inequality>>
10776 if Chars (S) = Name_Op_Eq
10777 and then Etype (S) = Standard_Boolean
10778 and then Present (Parent (S))
10779 and then not Is_Dispatching_Operation (S)
10781 Make_Inequality_Operator (S);
10782 Check_Untagged_Equality (S);
10784 end New_Overloaded_Entity;
10786 ---------------------
10787 -- Process_Formals --
10788 ---------------------
10790 procedure Process_Formals
10792 Related_Nod : Node_Id)
10794 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
10795 -- Determine whether an access type designates a type coming from a
10798 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
10799 -- Check whether the default has a class-wide type. After analysis the
10800 -- default has the type of the formal, so we must also check explicitly
10801 -- for an access attribute.
10803 ----------------------------------
10804 -- Designates_From_Limited_With --
10805 ----------------------------------
10807 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
10808 Desig : Entity_Id := Typ;
10811 if Is_Access_Type (Desig) then
10812 Desig := Directly_Designated_Type (Desig);
10815 if Is_Class_Wide_Type (Desig) then
10816 Desig := Root_Type (Desig);
10820 Ekind (Desig) = E_Incomplete_Type
10821 and then From_Limited_With (Desig);
10822 end Designates_From_Limited_With;
10824 ---------------------------
10825 -- Is_Class_Wide_Default --
10826 ---------------------------
10828 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
10830 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
10831 or else (Nkind (D) = N_Attribute_Reference
10832 and then Attribute_Name (D) = Name_Access
10833 and then Is_Class_Wide_Type (Etype (Prefix (D))));
10834 end Is_Class_Wide_Default;
10838 Context : constant Node_Id := Parent (Parent (T));
10840 Formal : Entity_Id;
10841 Formal_Type : Entity_Id;
10842 Param_Spec : Node_Id;
10845 Num_Out_Params : Nat := 0;
10846 First_Out_Param : Entity_Id := Empty;
10847 -- Used for setting Is_Only_Out_Parameter
10849 -- Start of processing for Process_Formals
10852 -- In order to prevent premature use of the formals in the same formal
10853 -- part, the Ekind is left undefined until all default expressions are
10854 -- analyzed. The Ekind is established in a separate loop at the end.
10856 Param_Spec := First (T);
10857 while Present (Param_Spec) loop
10858 Formal := Defining_Identifier (Param_Spec);
10859 Set_Never_Set_In_Source (Formal, True);
10860 Enter_Name (Formal);
10862 -- Case of ordinary parameters
10864 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
10865 Find_Type (Parameter_Type (Param_Spec));
10866 Ptype := Parameter_Type (Param_Spec);
10868 if Ptype = Error then
10872 Formal_Type := Entity (Ptype);
10874 if Is_Incomplete_Type (Formal_Type)
10876 (Is_Class_Wide_Type (Formal_Type)
10877 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
10879 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
10880 -- primitive operations, as long as their completion is
10881 -- in the same declarative part. If in the private part
10882 -- this means that the type cannot be a Taft-amendment type.
10883 -- Check is done on package exit. For access to subprograms,
10884 -- the use is legal for Taft-amendment types.
10886 -- Ada 2012: tagged incomplete types are allowed as generic
10887 -- formal types. They do not introduce dependencies and the
10888 -- corresponding generic subprogram does not have a delayed
10889 -- freeze, because it does not need a freeze node. However,
10890 -- it is still the case that untagged incomplete types cannot
10891 -- be Taft-amendment types and must be completed in private
10892 -- part, so the subprogram must appear in the list of private
10893 -- dependents of the type.
10895 if Is_Tagged_Type (Formal_Type)
10896 or else (Ada_Version >= Ada_2012
10897 and then not From_Limited_With (Formal_Type)
10898 and then not Is_Generic_Type (Formal_Type))
10900 if Ekind (Scope (Current_Scope)) = E_Package
10901 and then not Is_Generic_Type (Formal_Type)
10902 and then not Is_Class_Wide_Type (Formal_Type)
10905 (Parent (T), N_Access_Function_Definition,
10906 N_Access_Procedure_Definition)
10908 Append_Elmt (Current_Scope,
10909 Private_Dependents (Base_Type (Formal_Type)));
10911 -- Freezing is delayed to ensure that Register_Prim
10912 -- will get called for this operation, which is needed
10913 -- in cases where static dispatch tables aren't built.
10914 -- (Note that the same is done for controlling access
10915 -- parameter cases in function Access_Definition.)
10917 if not Is_Thunk (Current_Scope) then
10918 Set_Has_Delayed_Freeze (Current_Scope);
10923 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
10924 N_Access_Procedure_Definition)
10926 -- AI05-0151: Tagged incomplete types are allowed in all
10927 -- formal parts. Untagged incomplete types are not allowed
10928 -- in bodies. Limited views of either kind are not allowed
10929 -- if there is no place at which the non-limited view can
10930 -- become available.
10932 -- Incomplete formal untagged types are not allowed in
10933 -- subprogram bodies (but are legal in their declarations).
10934 -- This excludes bodies created for null procedures, which
10935 -- are basic declarations.
10937 if Is_Generic_Type (Formal_Type)
10938 and then not Is_Tagged_Type (Formal_Type)
10939 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
10942 ("invalid use of formal incomplete type", Param_Spec);
10944 elsif Ada_Version >= Ada_2012 then
10945 if Is_Tagged_Type (Formal_Type)
10946 and then (not From_Limited_With (Formal_Type)
10947 or else not In_Package_Body)
10951 elsif Nkind_In (Context, N_Accept_Statement,
10952 N_Accept_Alternative,
10954 or else (Nkind (Context) = N_Subprogram_Body
10955 and then Comes_From_Source (Context))
10958 ("invalid use of untagged incomplete type &",
10959 Ptype, Formal_Type);
10964 ("invalid use of incomplete type&",
10965 Param_Spec, Formal_Type);
10967 -- Further checks on the legality of incomplete types
10968 -- in formal parts are delayed until the freeze point
10969 -- of the enclosing subprogram or access to subprogram.
10973 elsif Ekind (Formal_Type) = E_Void then
10975 ("premature use of&",
10976 Parameter_Type (Param_Spec), Formal_Type);
10979 -- Ada 2012 (AI-142): Handle aliased parameters
10981 if Ada_Version >= Ada_2012
10982 and then Aliased_Present (Param_Spec)
10984 Set_Is_Aliased (Formal);
10987 -- Ada 2005 (AI-231): Create and decorate an internal subtype
10988 -- declaration corresponding to the null-excluding type of the
10989 -- formal in the enclosing scope. Finally, replace the parameter
10990 -- type of the formal with the internal subtype.
10992 if Ada_Version >= Ada_2005
10993 and then Null_Exclusion_Present (Param_Spec)
10995 if not Is_Access_Type (Formal_Type) then
10997 ("`NOT NULL` allowed only for an access type", Param_Spec);
11000 if Can_Never_Be_Null (Formal_Type)
11001 and then Comes_From_Source (Related_Nod)
11004 ("`NOT NULL` not allowed (& already excludes null)",
11005 Param_Spec, Formal_Type);
11009 Create_Null_Excluding_Itype
11011 Related_Nod => Related_Nod,
11012 Scope_Id => Scope (Current_Scope));
11014 -- If the designated type of the itype is an itype that is
11015 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11016 -- on the access subtype, to prevent order-of-elaboration
11017 -- issues in the backend.
11020 -- type T is access procedure;
11021 -- procedure Op (O : not null T);
11023 if Is_Itype (Directly_Designated_Type (Formal_Type))
11025 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11027 Set_Has_Delayed_Freeze (Formal_Type);
11032 -- An access formal type
11036 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11038 -- No need to continue if we already notified errors
11040 if not Present (Formal_Type) then
11044 -- Ada 2005 (AI-254)
11047 AD : constant Node_Id :=
11048 Access_To_Subprogram_Definition
11049 (Parameter_Type (Param_Spec));
11051 if Present (AD) and then Protected_Present (AD) then
11053 Replace_Anonymous_Access_To_Protected_Subprogram
11059 Set_Etype (Formal, Formal_Type);
11061 -- A formal parameter declared within a Ghost region is automatically
11062 -- Ghost (SPARK RM 6.9(2)).
11064 if Ghost_Mode > None then
11065 Set_Is_Ghost_Entity (Formal);
11068 -- Deal with default expression if present
11070 Default := Expression (Param_Spec);
11072 if Present (Default) then
11073 Check_SPARK_05_Restriction
11074 ("default expression is not allowed", Default);
11076 if Out_Present (Param_Spec) then
11078 ("default initialization only allowed for IN parameters",
11082 -- Do the special preanalysis of the expression (see section on
11083 -- "Handling of Default Expressions" in the spec of package Sem).
11085 Preanalyze_Spec_Expression (Default, Formal_Type);
11087 -- An access to constant cannot be the default for
11088 -- an access parameter that is an access to variable.
11090 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11091 and then not Is_Access_Constant (Formal_Type)
11092 and then Is_Access_Type (Etype (Default))
11093 and then Is_Access_Constant (Etype (Default))
11096 ("formal that is access to variable cannot be initialized "
11097 & "with an access-to-constant expression", Default);
11100 -- Check that the designated type of an access parameter's default
11101 -- is not a class-wide type unless the parameter's designated type
11102 -- is also class-wide.
11104 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11105 and then not Designates_From_Limited_With (Formal_Type)
11106 and then Is_Class_Wide_Default (Default)
11107 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11110 ("access to class-wide expression not allowed here", Default);
11113 -- Check incorrect use of dynamically tagged expressions
11115 if Is_Tagged_Type (Formal_Type) then
11116 Check_Dynamically_Tagged_Expression
11118 Typ => Formal_Type,
11119 Related_Nod => Default);
11123 -- Ada 2005 (AI-231): Static checks
11125 if Ada_Version >= Ada_2005
11126 and then Is_Access_Type (Etype (Formal))
11127 and then Can_Never_Be_Null (Etype (Formal))
11129 Null_Exclusion_Static_Checks (Param_Spec);
11132 -- The following checks are relevant only when SPARK_Mode is on as
11133 -- these are not standard Ada legality rules.
11135 if SPARK_Mode = On then
11136 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11138 -- A function cannot have a parameter of mode IN OUT or OUT
11141 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11143 ("function cannot have parameter of mode `OUT` or "
11144 & "`IN OUT`", Formal);
11147 -- A procedure cannot have an effectively volatile formal
11148 -- parameter of mode IN because it behaves as a constant
11149 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11151 elsif Ekind (Scope (Formal)) = E_Procedure
11152 and then Ekind (Formal) = E_In_Parameter
11153 and then Is_Effectively_Volatile (Formal)
11156 ("formal parameter of mode `IN` cannot be volatile", Formal);
11164 -- If this is the formal part of a function specification, analyze the
11165 -- subtype mark in the context where the formals are visible but not
11166 -- yet usable, and may hide outer homographs.
11168 if Nkind (Related_Nod) = N_Function_Specification then
11169 Analyze_Return_Type (Related_Nod);
11172 -- Now set the kind (mode) of each formal
11174 Param_Spec := First (T);
11175 while Present (Param_Spec) loop
11176 Formal := Defining_Identifier (Param_Spec);
11177 Set_Formal_Mode (Formal);
11179 if Ekind (Formal) = E_In_Parameter then
11180 Set_Default_Value (Formal, Expression (Param_Spec));
11182 if Present (Expression (Param_Spec)) then
11183 Default := Expression (Param_Spec);
11185 if Is_Scalar_Type (Etype (Default)) then
11186 if Nkind (Parameter_Type (Param_Spec)) /=
11187 N_Access_Definition
11189 Formal_Type := Entity (Parameter_Type (Param_Spec));
11193 (Related_Nod, Parameter_Type (Param_Spec));
11196 Apply_Scalar_Range_Check (Default, Formal_Type);
11200 elsif Ekind (Formal) = E_Out_Parameter then
11201 Num_Out_Params := Num_Out_Params + 1;
11203 if Num_Out_Params = 1 then
11204 First_Out_Param := Formal;
11207 elsif Ekind (Formal) = E_In_Out_Parameter then
11208 Num_Out_Params := Num_Out_Params + 1;
11211 -- Skip remaining processing if formal type was in error
11213 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11214 goto Next_Parameter;
11217 -- Force call by reference if aliased
11220 Conv : constant Convention_Id := Convention (Etype (Formal));
11222 if Is_Aliased (Formal) then
11223 Set_Mechanism (Formal, By_Reference);
11225 -- Warn if user asked this to be passed by copy
11227 if Conv = Convention_Ada_Pass_By_Copy then
11229 ("cannot pass aliased parameter & by copy??", Formal);
11232 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11234 elsif Conv = Convention_Ada_Pass_By_Copy then
11235 Set_Mechanism (Formal, By_Copy);
11237 elsif Conv = Convention_Ada_Pass_By_Reference then
11238 Set_Mechanism (Formal, By_Reference);
11246 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11247 Set_Is_Only_Out_Parameter (First_Out_Param);
11249 end Process_Formals;
11251 ----------------------------
11252 -- Reference_Body_Formals --
11253 ----------------------------
11255 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11260 if Error_Posted (Spec) then
11264 -- Iterate over both lists. They may be of different lengths if the two
11265 -- specs are not conformant.
11267 Fs := First_Formal (Spec);
11268 Fb := First_Formal (Bod);
11269 while Present (Fs) and then Present (Fb) loop
11270 Generate_Reference (Fs, Fb, 'b');
11272 if Style_Check then
11273 Style.Check_Identifier (Fb, Fs);
11276 Set_Spec_Entity (Fb, Fs);
11277 Set_Referenced (Fs, False);
11281 end Reference_Body_Formals;
11283 -------------------------
11284 -- Set_Actual_Subtypes --
11285 -------------------------
11287 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11289 Formal : Entity_Id;
11291 First_Stmt : Node_Id := Empty;
11292 AS_Needed : Boolean;
11295 -- If this is an empty initialization procedure, no need to create
11296 -- actual subtypes (small optimization).
11298 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11302 -- The subtype declarations may freeze the formals. The body generated
11303 -- for an expression function is not a freeze point, so do not emit
11304 -- these declarations (small loss of efficiency in rare cases).
11306 if Nkind (N) = N_Subprogram_Body
11307 and then Was_Expression_Function (N)
11312 Formal := First_Formal (Subp);
11313 while Present (Formal) loop
11314 T := Etype (Formal);
11316 -- We never need an actual subtype for a constrained formal
11318 if Is_Constrained (T) then
11319 AS_Needed := False;
11321 -- If we have unknown discriminants, then we do not need an actual
11322 -- subtype, or more accurately we cannot figure it out. Note that
11323 -- all class-wide types have unknown discriminants.
11325 elsif Has_Unknown_Discriminants (T) then
11326 AS_Needed := False;
11328 -- At this stage we have an unconstrained type that may need an
11329 -- actual subtype. For sure the actual subtype is needed if we have
11330 -- an unconstrained array type. However, in an instance, the type
11331 -- may appear as a subtype of the full view, while the actual is
11332 -- in fact private (in which case no actual subtype is needed) so
11333 -- check the kind of the base type.
11335 elsif Is_Array_Type (Base_Type (T)) then
11338 -- The only other case needing an actual subtype is an unconstrained
11339 -- record type which is an IN parameter (we cannot generate actual
11340 -- subtypes for the OUT or IN OUT case, since an assignment can
11341 -- change the discriminant values. However we exclude the case of
11342 -- initialization procedures, since discriminants are handled very
11343 -- specially in this context, see the section entitled "Handling of
11344 -- Discriminants" in Einfo.
11346 -- We also exclude the case of Discrim_SO_Functions (functions used
11347 -- in front-end layout mode for size/offset values), since in such
11348 -- functions only discriminants are referenced, and not only are such
11349 -- subtypes not needed, but they cannot always be generated, because
11350 -- of order of elaboration issues.
11352 elsif Is_Record_Type (T)
11353 and then Ekind (Formal) = E_In_Parameter
11354 and then Chars (Formal) /= Name_uInit
11355 and then not Is_Unchecked_Union (T)
11356 and then not Is_Discrim_SO_Function (Subp)
11360 -- All other cases do not need an actual subtype
11363 AS_Needed := False;
11366 -- Generate actual subtypes for unconstrained arrays and
11367 -- unconstrained discriminated records.
11370 if Nkind (N) = N_Accept_Statement then
11372 -- If expansion is active, the formal is replaced by a local
11373 -- variable that renames the corresponding entry of the
11374 -- parameter block, and it is this local variable that may
11375 -- require an actual subtype.
11377 if Expander_Active then
11378 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11380 Decl := Build_Actual_Subtype (T, Formal);
11383 if Present (Handled_Statement_Sequence (N)) then
11385 First (Statements (Handled_Statement_Sequence (N)));
11386 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11387 Mark_Rewrite_Insertion (Decl);
11389 -- If the accept statement has no body, there will be no
11390 -- reference to the actuals, so no need to compute actual
11397 Decl := Build_Actual_Subtype (T, Formal);
11398 Prepend (Decl, Declarations (N));
11399 Mark_Rewrite_Insertion (Decl);
11402 -- The declaration uses the bounds of an existing object, and
11403 -- therefore needs no constraint checks.
11405 Analyze (Decl, Suppress => All_Checks);
11406 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11408 -- We need to freeze manually the generated type when it is
11409 -- inserted anywhere else than in a declarative part.
11411 if Present (First_Stmt) then
11412 Insert_List_Before_And_Analyze (First_Stmt,
11413 Freeze_Entity (Defining_Identifier (Decl), N));
11415 -- Ditto if the type has a dynamic predicate, because the
11416 -- generated function will mention the actual subtype. The
11417 -- predicate may come from an explicit aspect of be inherited.
11419 elsif Has_Predicates (T) then
11420 Insert_List_Before_And_Analyze (Decl,
11421 Freeze_Entity (Defining_Identifier (Decl), N));
11424 if Nkind (N) = N_Accept_Statement
11425 and then Expander_Active
11427 Set_Actual_Subtype (Renamed_Object (Formal),
11428 Defining_Identifier (Decl));
11430 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11434 Next_Formal (Formal);
11436 end Set_Actual_Subtypes;
11438 ---------------------
11439 -- Set_Formal_Mode --
11440 ---------------------
11442 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11443 Spec : constant Node_Id := Parent (Formal_Id);
11444 Id : constant Entity_Id := Scope (Formal_Id);
11447 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11448 -- since we ensure that corresponding actuals are always valid at the
11449 -- point of the call.
11451 if Out_Present (Spec) then
11452 if Ekind_In (Id, E_Entry, E_Entry_Family)
11453 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11455 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11458 if Ekind_In (Id, E_Function, E_Generic_Function) then
11460 -- [IN] OUT parameters allowed for functions in Ada 2012
11462 if Ada_Version >= Ada_2012 then
11464 -- Even in Ada 2012 operators can only have IN parameters
11466 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11467 Error_Msg_N ("operators can only have IN parameters", Spec);
11470 if In_Present (Spec) then
11471 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11473 Set_Ekind (Formal_Id, E_Out_Parameter);
11476 -- But not in earlier versions of Ada
11479 Error_Msg_N ("functions can only have IN parameters", Spec);
11480 Set_Ekind (Formal_Id, E_In_Parameter);
11483 elsif In_Present (Spec) then
11484 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11487 Set_Ekind (Formal_Id, E_Out_Parameter);
11488 Set_Never_Set_In_Source (Formal_Id, True);
11489 Set_Is_True_Constant (Formal_Id, False);
11490 Set_Current_Value (Formal_Id, Empty);
11494 Set_Ekind (Formal_Id, E_In_Parameter);
11497 -- Set Is_Known_Non_Null for access parameters since the language
11498 -- guarantees that access parameters are always non-null. We also set
11499 -- Can_Never_Be_Null, since there is no way to change the value.
11501 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11503 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11504 -- null; In Ada 2005, only if then null_exclusion is explicit.
11506 if Ada_Version < Ada_2005
11507 or else Can_Never_Be_Null (Etype (Formal_Id))
11509 Set_Is_Known_Non_Null (Formal_Id);
11510 Set_Can_Never_Be_Null (Formal_Id);
11513 -- Ada 2005 (AI-231): Null-exclusion access subtype
11515 elsif Is_Access_Type (Etype (Formal_Id))
11516 and then Can_Never_Be_Null (Etype (Formal_Id))
11518 Set_Is_Known_Non_Null (Formal_Id);
11520 -- We can also set Can_Never_Be_Null (thus preventing some junk
11521 -- access checks) for the case of an IN parameter, which cannot
11522 -- be changed, or for an IN OUT parameter, which can be changed but
11523 -- not to a null value. But for an OUT parameter, the initial value
11524 -- passed in can be null, so we can't set this flag in that case.
11526 if Ekind (Formal_Id) /= E_Out_Parameter then
11527 Set_Can_Never_Be_Null (Formal_Id);
11531 Set_Mechanism (Formal_Id, Default_Mechanism);
11532 Set_Formal_Validity (Formal_Id);
11533 end Set_Formal_Mode;
11535 -------------------------
11536 -- Set_Formal_Validity --
11537 -------------------------
11539 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11541 -- If no validity checking, then we cannot assume anything about the
11542 -- validity of parameters, since we do not know there is any checking
11543 -- of the validity on the call side.
11545 if not Validity_Checks_On then
11548 -- If validity checking for parameters is enabled, this means we are
11549 -- not supposed to make any assumptions about argument values.
11551 elsif Validity_Check_Parameters then
11554 -- If we are checking in parameters, we will assume that the caller is
11555 -- also checking parameters, so we can assume the parameter is valid.
11557 elsif Ekind (Formal_Id) = E_In_Parameter
11558 and then Validity_Check_In_Params
11560 Set_Is_Known_Valid (Formal_Id, True);
11562 -- Similar treatment for IN OUT parameters
11564 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11565 and then Validity_Check_In_Out_Params
11567 Set_Is_Known_Valid (Formal_Id, True);
11569 end Set_Formal_Validity;
11571 ------------------------
11572 -- Subtype_Conformant --
11573 ------------------------
11575 function Subtype_Conformant
11576 (New_Id : Entity_Id;
11577 Old_Id : Entity_Id;
11578 Skip_Controlling_Formals : Boolean := False) return Boolean
11582 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
11583 Skip_Controlling_Formals => Skip_Controlling_Formals);
11585 end Subtype_Conformant;
11587 ---------------------
11588 -- Type_Conformant --
11589 ---------------------
11591 function Type_Conformant
11592 (New_Id : Entity_Id;
11593 Old_Id : Entity_Id;
11594 Skip_Controlling_Formals : Boolean := False) return Boolean
11598 May_Hide_Profile := False;
11600 (New_Id, Old_Id, Type_Conformant, False, Result,
11601 Skip_Controlling_Formals => Skip_Controlling_Formals);
11603 end Type_Conformant;
11605 -------------------------------
11606 -- Valid_Operator_Definition --
11607 -------------------------------
11609 procedure Valid_Operator_Definition (Designator : Entity_Id) is
11612 Id : constant Name_Id := Chars (Designator);
11616 F := First_Formal (Designator);
11617 while Present (F) loop
11620 if Present (Default_Value (F)) then
11622 ("default values not allowed for operator parameters",
11625 -- For function instantiations that are operators, we must check
11626 -- separately that the corresponding generic only has in-parameters.
11627 -- For subprogram declarations this is done in Set_Formal_Mode. Such
11628 -- an error could not arise in earlier versions of the language.
11630 elsif Ekind (F) /= E_In_Parameter then
11631 Error_Msg_N ("operators can only have IN parameters", F);
11637 -- Verify that user-defined operators have proper number of arguments
11638 -- First case of operators which can only be unary
11640 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
11643 -- Case of operators which can be unary or binary
11645 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
11646 N_OK := (N in 1 .. 2);
11648 -- All other operators can only be binary
11656 ("incorrect number of arguments for operator", Designator);
11660 and then Base_Type (Etype (Designator)) = Standard_Boolean
11661 and then not Is_Intrinsic_Subprogram (Designator)
11664 ("explicit definition of inequality not allowed", Designator);
11666 end Valid_Operator_Definition;