1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2020, 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_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id);
210 -- Preanalysis of default expressions of subprogram formals. N is the
211 -- expression to be analyzed and T is the expected type.
213 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
214 -- Formal_Id is an formal parameter entity. This procedure deals with
215 -- setting the proper validity status for this entity, which depends on
216 -- the kind of parameter and the validity checking mode.
218 ---------------------------------------------
219 -- Analyze_Abstract_Subprogram_Declaration --
220 ---------------------------------------------
222 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
223 Scop : constant Entity_Id := Current_Scope;
224 Subp_Id : constant Entity_Id :=
225 Analyze_Subprogram_Specification (Specification (N));
228 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
230 Generate_Definition (Subp_Id);
232 -- Set the SPARK mode from the current context (may be overwritten later
233 -- with explicit pragma).
235 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
236 Set_SPARK_Pragma_Inherited (Subp_Id);
238 -- Preserve relevant elaboration-related attributes of the context which
239 -- are no longer available or very expensive to recompute once analysis,
240 -- resolution, and expansion are over.
242 Mark_Elaboration_Attributes
247 Set_Is_Abstract_Subprogram (Subp_Id);
248 New_Overloaded_Entity (Subp_Id);
249 Check_Delayed_Subprogram (Subp_Id);
251 Set_Categorization_From_Scope (Subp_Id, Scop);
253 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
254 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
256 -- Issue a warning if the abstract subprogram is neither a dispatching
257 -- operation nor an operation that overrides an inherited subprogram or
258 -- predefined operator, since this most likely indicates a mistake.
260 elsif Warn_On_Redundant_Constructs
261 and then not Is_Dispatching_Operation (Subp_Id)
262 and then not Present (Overridden_Operation (Subp_Id))
263 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
264 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
267 ("abstract subprogram is not dispatching or overriding?r?", N);
270 Generate_Reference_To_Formals (Subp_Id);
271 Check_Eliminated (Subp_Id);
273 if Has_Aspects (N) then
274 Analyze_Aspect_Specifications (N, Subp_Id);
276 end Analyze_Abstract_Subprogram_Declaration;
278 ---------------------------------
279 -- Analyze_Expression_Function --
280 ---------------------------------
282 procedure Analyze_Expression_Function (N : Node_Id) is
283 Expr : constant Node_Id := Expression (N);
284 Loc : constant Source_Ptr := Sloc (N);
285 LocX : constant Source_Ptr := Sloc (Expr);
286 Spec : constant Node_Id := Specification (N);
296 Def_Id : Entity_Id := Empty;
298 -- If the expression is a completion, Prev is the entity whose
299 -- declaration is completed. Def_Id is needed to analyze the spec.
301 -- Start of processing for Analyze_Expression_Function
304 -- This is one of the occasions on which we transform the tree during
305 -- semantic analysis. If this is a completion, transform the expression
306 -- function into an equivalent subprogram body, and analyze it.
308 -- Expression functions are inlined unconditionally. The back-end will
309 -- determine whether this is possible.
311 Inline_Processing_Required := True;
313 -- Create a specification for the generated body. This must be done
314 -- prior to the analysis of the initial declaration.
316 New_Spec := Copy_Subprogram_Spec (Spec);
317 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
319 -- If there are previous overloadable entities with the same name,
320 -- check whether any of them is completed by the expression function.
321 -- In a generic context a formal subprogram has no completion.
324 and then Is_Overloadable (Prev)
325 and then not Is_Formal_Subprogram (Prev)
327 Def_Id := Analyze_Subprogram_Specification (Spec);
328 Prev := Find_Corresponding_Spec (N);
330 -- The previous entity may be an expression function as well, in
331 -- which case the redeclaration is illegal.
334 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
335 N_Expression_Function
337 Error_Msg_Sloc := Sloc (Prev);
338 Error_Msg_N ("& conflicts with declaration#", Def_Id);
343 Ret := Make_Simple_Return_Statement (LocX, Expr);
346 Make_Subprogram_Body (Loc,
347 Specification => New_Spec,
348 Declarations => Empty_List,
349 Handled_Statement_Sequence =>
350 Make_Handled_Sequence_Of_Statements (LocX,
351 Statements => New_List (Ret)));
352 Set_Was_Expression_Function (New_Body);
354 -- If the expression completes a generic subprogram, we must create a
355 -- separate node for the body, because at instantiation the original
356 -- node of the generic copy must be a generic subprogram body, and
357 -- cannot be a expression function. Otherwise we just rewrite the
358 -- expression with the non-generic body.
360 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
361 Insert_After (N, New_Body);
363 -- Propagate any aspects or pragmas that apply to the expression
364 -- function to the proper body when the expression function acts
367 if Has_Aspects (N) then
368 Move_Aspects (N, To => New_Body);
371 Relocate_Pragmas_To_Body (New_Body);
373 Rewrite (N, Make_Null_Statement (Loc));
374 Set_Has_Completion (Prev, False);
377 Set_Is_Inlined (Prev);
379 -- If the expression function is a completion, the previous declaration
380 -- must come from source. We know already that it appears in the current
381 -- scope. The entity itself may be internally created if within a body
385 and then Is_Overloadable (Prev)
386 and then not Is_Formal_Subprogram (Prev)
387 and then Comes_From_Source (Parent (Prev))
389 Set_Has_Completion (Prev, False);
390 Set_Is_Inlined (Prev);
392 -- AI12-0103: Expression functions that are a completion freeze their
393 -- expression but don't freeze anything else (unlike regular bodies).
395 -- Note that we cannot defer this freezing to the analysis of the
396 -- expression itself, because a freeze node might appear in a nested
397 -- scope, leading to an elaboration order issue in gigi.
398 -- As elsewhere, we do not emit freeze nodes within a generic unit.
400 if not Inside_A_Generic then
403 Typ => Etype (Def_Id),
408 -- For navigation purposes, indicate that the function is a body
410 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
411 Rewrite (N, New_Body);
413 -- Remove any existing aspects from the original node because the act
414 -- of rewriting causes the list to be shared between the two nodes.
416 Orig_N := Original_Node (N);
417 Remove_Aspects (Orig_N);
419 -- Propagate any pragmas that apply to expression function to the
420 -- proper body when the expression function acts as a completion.
421 -- Aspects are automatically transfered because of node rewriting.
423 Relocate_Pragmas_To_Body (N);
426 -- Once the aspects of the generated body have been analyzed, create
427 -- a copy for ASIS purposes and associate it with the original node.
428 -- Is this still needed???
430 if Has_Aspects (N) then
431 Set_Aspect_Specifications (Orig_N,
432 New_Copy_List_Tree (Aspect_Specifications (N)));
435 -- Prev is the previous entity with the same name, but it is can
436 -- be an unrelated spec that is not completed by the expression
437 -- function. In that case the relevant entity is the one in the body.
438 -- Not clear that the backend can inline it in this case ???
440 if Has_Completion (Prev) then
442 -- The formals of the expression function are body formals,
443 -- and do not appear in the ali file, which will only contain
444 -- references to the formals of the original subprogram spec.
451 F1 := First_Formal (Def_Id);
452 F2 := First_Formal (Prev);
454 while Present (F1) loop
455 Set_Spec_Entity (F1, F2);
462 Set_Is_Inlined (Defining_Entity (New_Body));
465 -- If this is not a completion, create both a declaration and a body, so
466 -- that the expression can be inlined whenever possible.
469 -- An expression function that is not a completion is not a
470 -- subprogram declaration, and thus cannot appear in a protected
473 if Nkind (Parent (N)) = N_Protected_Definition then
475 ("an expression function is not a legal protected operation", N);
478 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
480 -- Remove any existing aspects from the original node because the act
481 -- of rewriting causes the list to be shared between the two nodes.
483 Orig_N := Original_Node (N);
484 Remove_Aspects (Orig_N);
488 -- Once the aspects of the generated spec have been analyzed, create
489 -- a copy for ASIS purposes and associate it with the original node.
490 -- Is this still needed???
492 if Has_Aspects (N) then
493 Set_Aspect_Specifications (Orig_N,
494 New_Copy_List_Tree (Aspect_Specifications (N)));
497 -- If aspect SPARK_Mode was specified on the body, it needs to be
498 -- repeated both on the generated spec and the body.
500 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
502 if Present (Asp) then
503 Asp := New_Copy_Tree (Asp);
504 Set_Analyzed (Asp, False);
505 Set_Aspect_Specifications (New_Body, New_List (Asp));
508 Def_Id := Defining_Entity (N);
509 Set_Is_Inlined (Def_Id);
511 -- Establish the linkages between the spec and the body. These are
512 -- used when the expression function acts as the prefix of attribute
513 -- 'Access in order to freeze the original expression which has been
514 -- moved to the generated body.
516 Set_Corresponding_Body (N, Defining_Entity (New_Body));
517 Set_Corresponding_Spec (New_Body, Def_Id);
519 -- Within a generic preanalyze the original expression for name
520 -- capture. The body is also generated but plays no role in
521 -- this because it is not part of the original source.
523 if Inside_A_Generic then
524 Set_Has_Completion (Def_Id);
526 Install_Formals (Def_Id);
527 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
531 -- To prevent premature freeze action, insert the new body at the end
532 -- of the current declarations, or at the end of the package spec.
533 -- However, resolve usage names now, to prevent spurious visibility
534 -- on later entities. Note that the function can now be called in
535 -- the current declarative part, which will appear to be prior to
536 -- the presence of the body in the code. There are nevertheless no
537 -- order of elaboration issues because all name resolution has taken
538 -- place at the point of declaration.
541 Decls : List_Id := List_Containing (N);
542 Expr : constant Node_Id := Expression (Ret);
543 Par : constant Node_Id := Parent (Decls);
544 Typ : constant Entity_Id := Etype (Def_Id);
547 -- If this is a wrapper created for in an instance for a formal
548 -- subprogram, insert body after declaration, to be analyzed when
549 -- the enclosing instance is analyzed.
552 and then Is_Generic_Actual_Subprogram (Def_Id)
554 Insert_After (N, New_Body);
557 if Nkind (Par) = N_Package_Specification
558 and then Decls = Visible_Declarations (Par)
559 and then Present (Private_Declarations (Par))
560 and then not Is_Empty_List (Private_Declarations (Par))
562 Decls := Private_Declarations (Par);
565 Insert_After (Last (Decls), New_Body);
567 -- Preanalyze the expression if not already done above
569 if not Inside_A_Generic then
571 Install_Formals (Def_Id);
572 Preanalyze_Formal_Expression (Expr, Typ);
573 Check_Limited_Return (Original_Node (N), Expr, Typ);
580 -- Check incorrect use of dynamically tagged expression. This doesn't
581 -- fall out automatically when analyzing the generated function body,
582 -- because Check_Dynamically_Tagged_Expression deliberately ignores
583 -- nodes that don't come from source.
586 and then Nkind (Def_Id) in N_Has_Etype
587 and then Is_Tagged_Type (Etype (Def_Id))
589 Check_Dynamically_Tagged_Expression
591 Typ => Etype (Def_Id),
592 Related_Nod => Original_Node (N));
595 -- We must enforce checks for unreferenced formals in our newly
596 -- generated function, so we propagate the referenced flag from the
597 -- original spec to the new spec as well as setting Comes_From_Source.
599 if Present (Parameter_Specifications (New_Spec)) then
601 Form_New_Def : Entity_Id;
602 Form_New_Spec : Entity_Id;
603 Form_Old_Def : Entity_Id;
604 Form_Old_Spec : Entity_Id;
607 Form_New_Spec := First (Parameter_Specifications (New_Spec));
608 Form_Old_Spec := First (Parameter_Specifications (Spec));
610 while Present (Form_New_Spec) and then Present (Form_Old_Spec) loop
611 Form_New_Def := Defining_Identifier (Form_New_Spec);
612 Form_Old_Def := Defining_Identifier (Form_Old_Spec);
614 Set_Comes_From_Source (Form_New_Def, True);
616 -- Because of the usefulness of unreferenced controlling
617 -- formals we exempt them from unreferenced warnings by marking
618 -- them as always referenced.
620 Set_Referenced (Form_Old_Def,
621 (Is_Formal (Form_Old_Def)
622 and then Is_Controlling_Formal (Form_Old_Def))
623 or else Referenced (Form_Old_Def));
625 Next (Form_New_Spec);
626 Next (Form_Old_Spec);
630 end Analyze_Expression_Function;
632 ----------------------------------------
633 -- Analyze_Extended_Return_Statement --
634 ----------------------------------------
636 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
638 Check_Compiler_Unit ("extended return statement", N);
639 Analyze_Return_Statement (N);
640 end Analyze_Extended_Return_Statement;
642 ----------------------------
643 -- Analyze_Function_Call --
644 ----------------------------
646 procedure Analyze_Function_Call (N : Node_Id) is
647 Actuals : constant List_Id := Parameter_Associations (N);
648 Func_Nam : constant Node_Id := Name (N);
654 -- A call of the form A.B (X) may be an Ada 2005 call, which is
655 -- rewritten as B (A, X). If the rewriting is successful, the call
656 -- has been analyzed and we just return.
658 if Nkind (Func_Nam) = N_Selected_Component
659 and then Name (N) /= Func_Nam
660 and then Is_Rewrite_Substitution (N)
661 and then Present (Etype (N))
666 -- If error analyzing name, then set Any_Type as result type and return
668 if Etype (Func_Nam) = Any_Type then
669 Set_Etype (N, Any_Type);
673 -- Otherwise analyze the parameters
675 if Present (Actuals) then
676 Actual := First (Actuals);
677 while Present (Actual) loop
679 Check_Parameterless_Call (Actual);
685 end Analyze_Function_Call;
687 -----------------------------
688 -- Analyze_Function_Return --
689 -----------------------------
691 procedure Analyze_Function_Return (N : Node_Id) is
692 Loc : constant Source_Ptr := Sloc (N);
693 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
694 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
696 R_Type : constant Entity_Id := Etype (Scope_Id);
697 -- Function result subtype
699 procedure Check_Return_Construct_Accessibility (Return_Stmt : Node_Id);
700 -- Apply legality rule of 6.5 (5.9) to the access discriminants of an
701 -- aggregate in a return statement.
703 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
704 -- Check that the return_subtype_indication properly matches the result
705 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
707 ------------------------------------------
708 -- Check_Return_Construct_Accessibility --
709 ------------------------------------------
711 procedure Check_Return_Construct_Accessibility (Return_Stmt : Node_Id) is
713 Agg : Node_Id := Empty;
717 Process_Exprs : Boolean := False;
718 Return_Con : Node_Id;
721 -- Only perform checks on record types with access discriminants and
722 -- non-internally generated functions.
724 if not Is_Record_Type (R_Type)
725 or else not Has_Discriminants (R_Type)
726 or else not Comes_From_Source (Return_Stmt)
731 -- We are only interested in return statements
733 if not Nkind_In (Return_Stmt, N_Extended_Return_Statement,
734 N_Simple_Return_Statement)
739 -- Fetch the object from the return statement, in the case of a
740 -- simple return statement the expression is part of the node.
742 if Nkind (Return_Stmt) = N_Extended_Return_Statement then
743 -- Obtain the object definition from the expanded extended return
745 Return_Con := First (Return_Object_Declarations (Return_Stmt));
746 while Present (Return_Con) loop
747 -- Inspect the original node to avoid object declarations
748 -- expanded into renamings.
750 if Nkind (Original_Node (Return_Con)) = N_Object_Declaration
751 and then Comes_From_Source (Original_Node (Return_Con))
756 Nlists.Next (Return_Con);
759 pragma Assert (Present (Return_Con));
761 -- Could be dealing with a renaming
763 Return_Con := Original_Node (Return_Con);
765 Return_Con := Return_Stmt;
768 -- We may need to check an aggregate or a subtype indication
769 -- depending on how the discriminants were specified and whether
770 -- we are looking at an extended return statement.
772 if Nkind (Return_Con) = N_Object_Declaration
773 and then Nkind (Object_Definition (Return_Con))
774 = N_Subtype_Indication
776 Assoc := Original_Node
779 (Constraint (Object_Definition (Return_Con)))));
781 -- Qualified expressions may be nested
783 Agg := Original_Node (Expression (Return_Con));
784 while Nkind (Agg) = N_Qualified_Expression loop
785 Agg := Original_Node (Expression (Agg));
788 -- If we are looking at an aggregate instead of a function call we
789 -- can continue checking accessibility for the supplied
790 -- discriminant associations.
792 if Nkind (Agg) = N_Aggregate then
793 if Present (Expressions (Agg)) then
794 Assoc := First (Expressions (Agg));
795 Process_Exprs := True;
797 Assoc := First (Component_Associations (Agg));
800 -- Otherwise the expression is not of interest ???
807 -- Move through the discriminants checking the accessibility level
808 -- of each co-extension's associated expression.
810 Discr := First_Discriminant (R_Type);
811 while Present (Discr) loop
812 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
814 if Nkind (Assoc) = N_Attribute_Reference then
816 elsif Nkind_In (Assoc, N_Component_Association,
817 N_Discriminant_Association)
819 Expr := Expression (Assoc);
824 -- This anonymous access discriminant has an associated
825 -- expression which needs checking.
828 and then Nkind (Expr) = N_Attribute_Reference
829 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
831 -- Obtain the object to perform static checks on by moving
832 -- up the prefixes in the expression taking into account
833 -- named access types and renamed objects within the
836 Obj := Original_Node (Prefix (Expr));
838 while Nkind_In (Obj, N_Explicit_Dereference,
840 N_Selected_Component)
842 -- When we encounter a named access type then we can
843 -- ignore accessibility checks on the dereference.
845 if Ekind (Etype (Original_Node (Prefix (Obj))))
847 E_Access_Protected_Subprogram_Type
849 if Nkind (Obj) = N_Selected_Component then
850 Obj := Selector_Name (Obj);
852 Obj := Original_Node (Prefix (Obj));
857 Obj := Original_Node (Prefix (Obj));
860 if Nkind (Obj) = N_Selected_Component then
861 Obj := Selector_Name (Obj);
864 -- Check for renamings
866 pragma Assert (Is_Entity_Name (Obj));
868 if Present (Renamed_Object (Entity (Obj))) then
869 Obj := Renamed_Object (Entity (Obj));
875 -- Do not check aliased formals or function calls. A
876 -- run-time check may still be needed ???
878 if Is_Formal (Entity (Obj))
879 and then Is_Aliased (Entity (Obj))
883 elsif Object_Access_Level (Obj) >
884 Scope_Depth (Scope (Scope_Id))
887 ("access discriminant in return aggregate would "
888 & "be a dangling reference", Obj);
893 Next_Discriminant (Discr);
895 if not Is_List_Member (Assoc) then
901 -- After aggregate expressions, examine component associations if
906 and then Process_Exprs
907 and then Present (Component_Associations (Agg))
909 Assoc := First (Component_Associations (Agg));
910 Process_Exprs := False;
916 end Check_Return_Construct_Accessibility;
918 -------------------------------------
919 -- Check_Return_Subtype_Indication --
920 -------------------------------------
922 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
923 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
925 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
926 -- Subtype given in the extended return statement (must match R_Type)
928 Subtype_Ind : constant Node_Id :=
929 Object_Definition (Original_Node (Obj_Decl));
931 procedure Error_No_Match (N : Node_Id);
932 -- Output error messages for case where types do not statically
933 -- match. N is the location for the messages.
939 procedure Error_No_Match (N : Node_Id) is
942 ("subtype must statically match function result subtype", N);
944 if not Predicates_Match (R_Stm_Type, R_Type) then
945 Error_Msg_Node_2 := R_Type;
947 ("\predicate of& does not match predicate of&",
952 -- Start of processing for Check_Return_Subtype_Indication
955 -- First, avoid cascaded errors
957 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
961 -- "return access T" case; check that the return statement also has
962 -- "access T", and that the subtypes statically match:
963 -- if this is an access to subprogram the signatures must match.
965 if Is_Anonymous_Access_Type (R_Type) then
966 if Is_Anonymous_Access_Type (R_Stm_Type) then
967 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
969 if Base_Type (Designated_Type (R_Stm_Type)) /=
970 Base_Type (Designated_Type (R_Type))
971 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
973 Error_No_Match (Subtype_Mark (Subtype_Ind));
977 -- For two anonymous access to subprogram types, the types
978 -- themselves must be type conformant.
980 if not Conforming_Types
981 (R_Stm_Type, R_Type, Fully_Conformant)
983 Error_No_Match (Subtype_Ind);
988 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
991 -- If the return object is of an anonymous access type, then report
992 -- an error if the function's result type is not also anonymous.
994 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
995 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
997 ("anonymous access not allowed for function with named access "
998 & "result", Subtype_Ind);
1000 -- Subtype indication case: check that the return object's type is
1001 -- covered by the result type, and that the subtypes statically match
1002 -- when the result subtype is constrained. Also handle record types
1003 -- with unknown discriminants for which we have built the underlying
1004 -- record view. Coverage is needed to allow specific-type return
1005 -- objects when the result type is class-wide (see AI05-32).
1007 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
1008 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1011 (Base_Type (R_Type),
1012 Underlying_Record_View (Base_Type (R_Stm_Type))))
1014 -- A null exclusion may be present on the return type, on the
1015 -- function specification, on the object declaration or on the
1018 if Is_Access_Type (R_Type)
1020 (Can_Never_Be_Null (R_Type)
1021 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1022 Can_Never_Be_Null (R_Stm_Type)
1024 Error_No_Match (Subtype_Ind);
1027 -- AI05-103: for elementary types, subtypes must statically match
1029 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1030 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1031 Error_No_Match (Subtype_Ind);
1035 -- All remaining cases are illegal
1037 -- Note: previous versions of this subprogram allowed the return
1038 -- value to be the ancestor of the return type if the return type
1039 -- was a null extension. This was plainly incorrect.
1043 ("wrong type for return_subtype_indication", Subtype_Ind);
1045 end Check_Return_Subtype_Indication;
1047 ---------------------
1048 -- Local Variables --
1049 ---------------------
1052 Obj_Decl : Node_Id := Empty;
1054 -- Start of processing for Analyze_Function_Return
1057 Set_Return_Present (Scope_Id);
1059 if Nkind (N) = N_Simple_Return_Statement then
1060 Expr := Expression (N);
1062 -- Guard against a malformed expression. The parser may have tried to
1063 -- recover but the node is not analyzable.
1065 if Nkind (Expr) = N_Error then
1066 Set_Etype (Expr, Any_Type);
1067 Expander_Mode_Save_And_Set (False);
1071 -- The resolution of a controlled [extension] aggregate associated
1072 -- with a return statement creates a temporary which needs to be
1073 -- finalized on function exit. Wrap the return statement inside a
1074 -- block so that the finalization machinery can detect this case.
1075 -- This early expansion is done only when the return statement is
1076 -- not part of a handled sequence of statements.
1078 if Nkind_In (Expr, N_Aggregate,
1079 N_Extension_Aggregate)
1080 and then Needs_Finalization (R_Type)
1081 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1084 Make_Block_Statement (Loc,
1085 Handled_Statement_Sequence =>
1086 Make_Handled_Sequence_Of_Statements (Loc,
1087 Statements => New_List (Relocate_Node (N)))));
1095 -- Ada 2005 (AI-251): If the type of the returned object is
1096 -- an access to an interface type then we add an implicit type
1097 -- conversion to force the displacement of the "this" pointer to
1098 -- reference the secondary dispatch table. We cannot delay the
1099 -- generation of this implicit conversion until the expansion
1100 -- because in this case the type resolution changes the decoration
1101 -- of the expression node to match R_Type; by contrast, if the
1102 -- returned object is a class-wide interface type then it is too
1103 -- early to generate here the implicit conversion since the return
1104 -- statement may be rewritten by the expander into an extended
1105 -- return statement whose expansion takes care of adding the
1106 -- implicit type conversion to displace the pointer to the object.
1109 and then Serious_Errors_Detected = 0
1110 and then Is_Access_Type (R_Type)
1111 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1112 and then Is_Interface (Designated_Type (R_Type))
1113 and then Is_Progenitor (Designated_Type (R_Type),
1114 Designated_Type (Etype (Expr)))
1116 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1120 Resolve (Expr, R_Type);
1121 Check_Limited_Return (N, Expr, R_Type);
1123 Check_Return_Construct_Accessibility (N);
1126 -- RETURN only allowed in SPARK as the last statement in function
1128 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1130 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1131 or else Present (Next (N)))
1133 Check_SPARK_05_Restriction
1134 ("RETURN should be the last statement in function", N);
1138 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1139 Obj_Decl := Last (Return_Object_Declarations (N));
1141 -- Analyze parts specific to extended_return_statement:
1144 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1145 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1148 Expr := Expression (Obj_Decl);
1150 -- Note: The check for OK_For_Limited_Init will happen in
1151 -- Analyze_Object_Declaration; we treat it as a normal
1152 -- object declaration.
1154 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1157 Check_Return_Subtype_Indication (Obj_Decl);
1159 if Present (HSS) then
1162 if Present (Exception_Handlers (HSS)) then
1164 -- ???Has_Nested_Block_With_Handler needs to be set.
1165 -- Probably by creating an actual N_Block_Statement.
1166 -- Probably in Expand.
1172 -- Mark the return object as referenced, since the return is an
1173 -- implicit reference of the object.
1175 Set_Referenced (Defining_Identifier (Obj_Decl));
1177 Check_References (Stm_Entity);
1179 Check_Return_Construct_Accessibility (N);
1181 -- Check RM 6.5 (5.9/3)
1184 if Ada_Version < Ada_2012 then
1186 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1187 -- Can it really happen (extended return???)
1190 ("aliased only allowed for limited return objects "
1191 & "in Ada 2012??", N);
1193 elsif not Is_Limited_View (R_Type) then
1195 ("aliased only allowed for limited return objects", N);
1201 -- Case of Expr present
1203 if Present (Expr) then
1205 -- Defend against previous errors
1207 if Nkind (Expr) = N_Empty
1208 or else No (Etype (Expr))
1213 -- Apply constraint check. Note that this is done before the implicit
1214 -- conversion of the expression done for anonymous access types to
1215 -- ensure correct generation of the null-excluding check associated
1216 -- with null-excluding expressions found in return statements. We
1217 -- don't need a check if the subtype of the return object is the
1218 -- same as the result subtype of the function.
1220 if Nkind (N) /= N_Extended_Return_Statement
1221 or else Nkind (Obj_Decl) /= N_Object_Declaration
1222 or else Nkind (Object_Definition (Obj_Decl)) not in N_Has_Entity
1223 or else Entity (Object_Definition (Obj_Decl)) /= R_Type
1225 Apply_Constraint_Check (Expr, R_Type);
1228 -- The return value is converted to the return type of the function,
1229 -- which implies a predicate check if the return type is predicated.
1230 -- We do not apply the check to a case expression because it will
1231 -- be expanded into a series of return statements, each of which
1232 -- will receive a predicate check.
1234 if Nkind (Expr) /= N_Case_Expression then
1235 Apply_Predicate_Check (Expr, R_Type);
1238 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1239 -- type, apply an implicit conversion of the expression to that type
1240 -- to force appropriate static and run-time accessibility checks.
1242 if Ada_Version >= Ada_2005
1243 and then Ekind (R_Type) = E_Anonymous_Access_Type
1245 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1246 Analyze_And_Resolve (Expr, R_Type);
1248 -- If this is a local anonymous access to subprogram, the
1249 -- accessibility check can be applied statically. The return is
1250 -- illegal if the access type of the return expression is declared
1251 -- inside of the subprogram (except if it is the subtype indication
1252 -- of an extended return statement).
1254 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1255 if not Comes_From_Source (Current_Scope)
1256 or else Ekind (Current_Scope) = E_Return_Statement
1261 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1263 Error_Msg_N ("cannot return local access to subprogram", N);
1266 -- The expression cannot be of a formal incomplete type
1268 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1269 and then Is_Generic_Type (Etype (Expr))
1272 ("cannot return expression of a formal incomplete type", N);
1275 -- If the result type is class-wide, then check that the return
1276 -- expression's type is not declared at a deeper level than the
1277 -- function (RM05-6.5(5.6/2)).
1279 if Ada_Version >= Ada_2005
1280 and then Is_Class_Wide_Type (R_Type)
1282 if Type_Access_Level (Etype (Expr)) >
1283 Subprogram_Access_Level (Scope_Id)
1286 ("level of return expression type is deeper than "
1287 & "class-wide function!", Expr);
1291 -- Check incorrect use of dynamically tagged expression
1293 if Is_Tagged_Type (R_Type) then
1294 Check_Dynamically_Tagged_Expression
1300 -- ??? A real run-time accessibility check is needed in cases
1301 -- involving dereferences of access parameters. For now we just
1302 -- check the static cases.
1304 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1305 and then Is_Limited_View (Etype (Scope_Id))
1306 and then Object_Access_Level (Expr) >
1307 Subprogram_Access_Level (Scope_Id)
1309 -- Suppress the message in a generic, where the rewriting
1312 if Inside_A_Generic then
1317 Make_Raise_Program_Error (Loc,
1318 Reason => PE_Accessibility_Check_Failed));
1321 Error_Msg_Warn := SPARK_Mode /= On;
1322 Error_Msg_N ("cannot return a local value by reference<<", N);
1323 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1327 if Known_Null (Expr)
1328 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1329 and then Null_Exclusion_Present (Parent (Scope_Id))
1331 Apply_Compile_Time_Constraint_Error
1333 Msg => "(Ada 2005) null not allowed for "
1334 & "null-excluding return??",
1335 Reason => CE_Null_Not_Allowed);
1338 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1339 -- has no initializing expression.
1341 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1342 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1343 Subprogram_Access_Level (Scope_Id)
1346 ("level of return expression type is deeper than "
1347 & "class-wide function!", Obj_Decl);
1350 end Analyze_Function_Return;
1352 -------------------------------------
1353 -- Analyze_Generic_Subprogram_Body --
1354 -------------------------------------
1356 procedure Analyze_Generic_Subprogram_Body
1360 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1361 Kind : constant Entity_Kind := Ekind (Gen_Id);
1362 Body_Id : Entity_Id;
1367 -- Copy body and disable expansion while analyzing the generic For a
1368 -- stub, do not copy the stub (which would load the proper body), this
1369 -- will be done when the proper body is analyzed.
1371 if Nkind (N) /= N_Subprogram_Body_Stub then
1372 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1375 -- Once the contents of the generic copy and the template are
1376 -- swapped, do the same for their respective aspect specifications.
1378 Exchange_Aspects (N, New_N);
1380 -- Collect all contract-related source pragmas found within the
1381 -- template and attach them to the contract of the subprogram body.
1382 -- This contract is used in the capture of global references within
1385 Create_Generic_Contract (N);
1390 Spec := Specification (N);
1392 -- Within the body of the generic, the subprogram is callable, and
1393 -- behaves like the corresponding non-generic unit.
1395 Body_Id := Defining_Entity (Spec);
1397 if Kind = E_Generic_Procedure
1398 and then Nkind (Spec) /= N_Procedure_Specification
1400 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1403 elsif Kind = E_Generic_Function
1404 and then Nkind (Spec) /= N_Function_Specification
1406 Error_Msg_N ("invalid body for generic function ", Body_Id);
1410 Set_Corresponding_Body (Gen_Decl, Body_Id);
1412 if Has_Completion (Gen_Id)
1413 and then Nkind (Parent (N)) /= N_Subunit
1415 Error_Msg_N ("duplicate generic body", N);
1418 Set_Has_Completion (Gen_Id);
1421 if Nkind (N) = N_Subprogram_Body_Stub then
1422 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1424 Set_Corresponding_Spec (N, Gen_Id);
1427 if Nkind (Parent (N)) = N_Compilation_Unit then
1428 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1431 -- Make generic parameters immediately visible in the body. They are
1432 -- needed to process the formals declarations. Then make the formals
1433 -- visible in a separate step.
1435 Push_Scope (Gen_Id);
1439 First_Ent : Entity_Id;
1442 First_Ent := First_Entity (Gen_Id);
1445 while Present (E) and then not Is_Formal (E) loop
1450 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1452 -- Now generic formals are visible, and the specification can be
1453 -- analyzed, for subsequent conformance check.
1455 Body_Id := Analyze_Subprogram_Specification (Spec);
1457 -- Make formal parameters visible
1461 -- E is the first formal parameter, we loop through the formals
1462 -- installing them so that they will be visible.
1464 Set_First_Entity (Gen_Id, E);
1465 while Present (E) loop
1471 -- Visible generic entity is callable within its own body
1473 Set_Ekind (Gen_Id, Ekind (Body_Id));
1474 Set_Ekind (Body_Id, E_Subprogram_Body);
1475 Set_Convention (Body_Id, Convention (Gen_Id));
1476 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1477 Set_Scope (Body_Id, Scope (Gen_Id));
1479 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1481 if Nkind (N) = N_Subprogram_Body_Stub then
1483 -- No body to analyze, so restore state of generic unit
1485 Set_Ekind (Gen_Id, Kind);
1486 Set_Ekind (Body_Id, Kind);
1488 if Present (First_Ent) then
1489 Set_First_Entity (Gen_Id, First_Ent);
1496 -- If this is a compilation unit, it must be made visible explicitly,
1497 -- because the compilation of the declaration, unlike other library
1498 -- unit declarations, does not. If it is not a unit, the following
1499 -- is redundant but harmless.
1501 Set_Is_Immediately_Visible (Gen_Id);
1502 Reference_Body_Formals (Gen_Id, Body_Id);
1504 if Is_Child_Unit (Gen_Id) then
1505 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1508 Set_Actual_Subtypes (N, Current_Scope);
1510 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1511 Set_SPARK_Pragma_Inherited (Body_Id);
1513 -- Analyze any aspect specifications that appear on the generic
1516 if Has_Aspects (N) then
1517 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1520 Analyze_Declarations (Declarations (N));
1523 -- Process the contract of the subprogram body after all declarations
1524 -- have been analyzed. This ensures that any contract-related pragmas
1525 -- are available through the N_Contract node of the body.
1527 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1529 Analyze (Handled_Statement_Sequence (N));
1530 Save_Global_References (Original_Node (N));
1532 -- Prior to exiting the scope, include generic formals again (if any
1533 -- are present) in the set of local entities.
1535 if Present (First_Ent) then
1536 Set_First_Entity (Gen_Id, First_Ent);
1539 Check_References (Gen_Id);
1542 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1543 Update_Use_Clause_Chain;
1544 Validate_Categorization_Dependency (N, Gen_Id);
1546 Check_Subprogram_Order (N);
1548 -- Outside of its body, unit is generic again
1550 Set_Ekind (Gen_Id, Kind);
1551 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1554 Style.Check_Identifier (Body_Id, Gen_Id);
1558 end Analyze_Generic_Subprogram_Body;
1560 ----------------------------
1561 -- Analyze_Null_Procedure --
1562 ----------------------------
1564 -- WARNING: This routine manages Ghost regions. Return statements must be
1565 -- replaced by gotos that jump to the end of the routine and restore the
1568 procedure Analyze_Null_Procedure
1570 Is_Completion : out Boolean)
1572 Loc : constant Source_Ptr := Sloc (N);
1573 Spec : constant Node_Id := Specification (N);
1575 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1576 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1577 Saved_ISMP : constant Boolean :=
1578 Ignore_SPARK_Mode_Pragmas_In_Instance;
1579 -- Save the Ghost and SPARK mode-related data to restore on exit
1581 Designator : Entity_Id;
1583 Null_Body : Node_Id := Empty;
1584 Null_Stmt : Node_Id := Null_Statement (Spec);
1588 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1590 -- A null procedure is Ghost when it is stand-alone and is subject to
1591 -- pragma Ghost, or when the corresponding spec is Ghost. Set the mode
1592 -- now, to ensure that any nodes generated during analysis and expansion
1593 -- are properly marked as Ghost.
1595 if Present (Prev) then
1596 Mark_And_Set_Ghost_Body (N, Prev);
1599 -- Capture the profile of the null procedure before analysis, for
1600 -- expansion at the freeze point and at each point of call. The body is
1601 -- used if the procedure has preconditions, or if it is a completion. In
1602 -- the first case the body is analyzed at the freeze point, in the other
1603 -- it replaces the null procedure declaration.
1605 -- For a null procedure that comes from source, a NULL statement is
1606 -- provided by the parser, which carries the source location of the
1607 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1608 -- from expansion, create one now.
1610 if No (Null_Stmt) then
1611 Null_Stmt := Make_Null_Statement (Loc);
1615 Make_Subprogram_Body (Loc,
1616 Specification => New_Copy_Tree (Spec),
1617 Declarations => New_List,
1618 Handled_Statement_Sequence =>
1619 Make_Handled_Sequence_Of_Statements (Loc,
1620 Statements => New_List (Null_Stmt)));
1622 -- Create new entities for body and formals
1624 Set_Defining_Unit_Name (Specification (Null_Body),
1625 Make_Defining_Identifier
1626 (Sloc (Defining_Entity (N)),
1627 Chars (Defining_Entity (N))));
1629 Form := First (Parameter_Specifications (Specification (Null_Body)));
1630 while Present (Form) loop
1631 Set_Defining_Identifier (Form,
1632 Make_Defining_Identifier
1633 (Sloc (Defining_Identifier (Form)),
1634 Chars (Defining_Identifier (Form))));
1638 -- Determine whether the null procedure may be a completion of a generic
1639 -- suprogram, in which case we use the new null body as the completion
1640 -- and set minimal semantic information on the original declaration,
1641 -- which is rewritten as a null statement.
1643 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1644 Insert_Before (N, Null_Body);
1645 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1647 Rewrite (N, Make_Null_Statement (Loc));
1648 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1649 Is_Completion := True;
1654 -- Resolve the types of the formals now, because the freeze point may
1655 -- appear in a different context, e.g. an instantiation.
1657 Form := First (Parameter_Specifications (Specification (Null_Body)));
1658 while Present (Form) loop
1659 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1660 Find_Type (Parameter_Type (Form));
1662 elsif No (Access_To_Subprogram_Definition
1663 (Parameter_Type (Form)))
1665 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1667 -- The case of a null procedure with a formal that is an
1668 -- access-to-subprogram type, and that is used as an actual
1669 -- in an instantiation is left to the enthusiastic reader.
1679 -- If there are previous overloadable entities with the same name, check
1680 -- whether any of them is completed by the null procedure.
1682 if Present (Prev) and then Is_Overloadable (Prev) then
1683 Designator := Analyze_Subprogram_Specification (Spec);
1684 Prev := Find_Corresponding_Spec (N);
1687 if No (Prev) or else not Comes_From_Source (Prev) then
1688 Designator := Analyze_Subprogram_Specification (Spec);
1689 Set_Has_Completion (Designator);
1691 -- Signal to caller that this is a procedure declaration
1693 Is_Completion := False;
1695 -- Null procedures are always inlined, but generic formal subprograms
1696 -- which appear as such in the internal instance of formal packages,
1697 -- need no completion and are not marked Inline.
1700 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1702 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1703 Set_Body_To_Inline (N, Null_Body);
1704 Set_Is_Inlined (Designator);
1708 -- The null procedure is a completion. We unconditionally rewrite
1709 -- this as a null body (even if expansion is not active), because
1710 -- there are various error checks that are applied on this body
1711 -- when it is analyzed (e.g. correct aspect placement).
1713 if Has_Completion (Prev) then
1714 Error_Msg_Sloc := Sloc (Prev);
1715 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1718 Check_Previous_Null_Procedure (N, Prev);
1720 Is_Completion := True;
1721 Rewrite (N, Null_Body);
1726 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
1727 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1728 end Analyze_Null_Procedure;
1730 -----------------------------
1731 -- Analyze_Operator_Symbol --
1732 -----------------------------
1734 -- An operator symbol such as "+" or "and" may appear in context where the
1735 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1736 -- is just a string, as in (conjunction = "or"). In these cases the parser
1737 -- generates this node, and the semantics does the disambiguation. Other
1738 -- such case are actuals in an instantiation, the generic unit in an
1739 -- instantiation, and pragma arguments.
1741 procedure Analyze_Operator_Symbol (N : Node_Id) is
1742 Par : constant Node_Id := Parent (N);
1745 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1746 or else Nkind (Par) = N_Function_Instantiation
1747 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1748 or else (Nkind (Par) = N_Pragma_Argument_Association
1749 and then not Is_Pragma_String_Literal (Par))
1750 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1751 or else (Nkind (Par) = N_Attribute_Reference
1752 and then Attribute_Name (Par) /= Name_Value)
1754 Find_Direct_Name (N);
1757 Change_Operator_Symbol_To_String_Literal (N);
1760 end Analyze_Operator_Symbol;
1762 -----------------------------------
1763 -- Analyze_Parameter_Association --
1764 -----------------------------------
1766 procedure Analyze_Parameter_Association (N : Node_Id) is
1768 Analyze (Explicit_Actual_Parameter (N));
1769 end Analyze_Parameter_Association;
1771 ----------------------------
1772 -- Analyze_Procedure_Call --
1773 ----------------------------
1775 -- WARNING: This routine manages Ghost regions. Return statements must be
1776 -- replaced by gotos that jump to the end of the routine and restore the
1779 procedure Analyze_Procedure_Call (N : Node_Id) is
1780 procedure Analyze_Call_And_Resolve;
1781 -- Do Analyze and Resolve calls for procedure call. At the end, check
1782 -- for illegal order dependence.
1783 -- ??? where is the check for illegal order dependencies?
1785 ------------------------------
1786 -- Analyze_Call_And_Resolve --
1787 ------------------------------
1789 procedure Analyze_Call_And_Resolve is
1791 if Nkind (N) = N_Procedure_Call_Statement then
1793 Resolve (N, Standard_Void_Type);
1797 end Analyze_Call_And_Resolve;
1801 Actuals : constant List_Id := Parameter_Associations (N);
1802 Loc : constant Source_Ptr := Sloc (N);
1803 P : constant Node_Id := Name (N);
1805 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1806 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1807 -- Save the Ghost-related attributes to restore on exit
1812 -- Start of processing for Analyze_Procedure_Call
1815 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1816 -- a procedure call or an entry call. The prefix may denote an access
1817 -- to subprogram type, in which case an implicit dereference applies.
1818 -- If the prefix is an indexed component (without implicit dereference)
1819 -- then the construct denotes a call to a member of an entire family.
1820 -- If the prefix is a simple name, it may still denote a call to a
1821 -- parameterless member of an entry family. Resolution of these various
1822 -- interpretations is delicate.
1824 -- Do not analyze machine code statements to avoid rejecting them in
1827 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1828 Set_Etype (P, Standard_Void_Type);
1833 -- If this is a call of the form Obj.Op, the call may have been analyzed
1834 -- and possibly rewritten into a block, in which case we are done.
1836 if Analyzed (N) then
1839 -- If there is an error analyzing the name (which may have been
1840 -- rewritten if the original call was in prefix notation) then error
1841 -- has been emitted already, mark node and return.
1843 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1844 Set_Etype (N, Any_Type);
1848 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1849 -- Set the mode now to ensure that any nodes generated during analysis
1850 -- and expansion are properly marked as Ghost.
1852 Mark_And_Set_Ghost_Procedure_Call (N);
1854 -- Otherwise analyze the parameters
1856 if Present (Actuals) then
1857 Actual := First (Actuals);
1859 while Present (Actual) loop
1861 Check_Parameterless_Call (Actual);
1866 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1868 if Nkind (P) = N_Attribute_Reference
1869 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1871 Name_Elab_Subp_Body)
1873 if Present (Actuals) then
1875 ("no parameters allowed for this call", First (Actuals));
1879 Set_Etype (N, Standard_Void_Type);
1882 elsif Is_Entity_Name (P)
1883 and then Is_Record_Type (Etype (Entity (P)))
1884 and then Remote_AST_I_Dereference (P)
1888 elsif Is_Entity_Name (P)
1889 and then Ekind (Entity (P)) /= E_Entry_Family
1891 if Is_Access_Type (Etype (P))
1892 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1893 and then No (Actuals)
1894 and then Comes_From_Source (N)
1896 Error_Msg_N ("missing explicit dereference in call", N);
1899 Analyze_Call_And_Resolve;
1901 -- If the prefix is the simple name of an entry family, this is a
1902 -- parameterless call from within the task body itself.
1904 elsif Is_Entity_Name (P)
1905 and then Nkind (P) = N_Identifier
1906 and then Ekind (Entity (P)) = E_Entry_Family
1907 and then Present (Actuals)
1908 and then No (Next (First (Actuals)))
1910 -- Can be call to parameterless entry family. What appears to be the
1911 -- sole argument is in fact the entry index. Rewrite prefix of node
1912 -- accordingly. Source representation is unchanged by this
1916 Make_Indexed_Component (Loc,
1918 Make_Selected_Component (Loc,
1919 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1920 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1921 Expressions => Actuals);
1922 Set_Name (N, New_N);
1923 Set_Etype (New_N, Standard_Void_Type);
1924 Set_Parameter_Associations (N, No_List);
1925 Analyze_Call_And_Resolve;
1927 elsif Nkind (P) = N_Explicit_Dereference then
1928 if Ekind (Etype (P)) = E_Subprogram_Type then
1929 Analyze_Call_And_Resolve;
1931 Error_Msg_N ("expect access to procedure in call", P);
1934 -- The name can be a selected component or an indexed component that
1935 -- yields an access to subprogram. Such a prefix is legal if the call
1936 -- has parameter associations.
1938 elsif Is_Access_Type (Etype (P))
1939 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1941 if Present (Actuals) then
1942 Analyze_Call_And_Resolve;
1944 Error_Msg_N ("missing explicit dereference in call ", N);
1947 -- If not an access to subprogram, then the prefix must resolve to the
1948 -- name of an entry, entry family, or protected operation.
1950 -- For the case of a simple entry call, P is a selected component where
1951 -- the prefix is the task and the selector name is the entry. A call to
1952 -- a protected procedure will have the same syntax. If the protected
1953 -- object contains overloaded operations, the entity may appear as a
1954 -- function, the context will select the operation whose type is Void.
1956 elsif Nkind (P) = N_Selected_Component
1957 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1961 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1962 -- in prefix notation may still be missing its controlling argument,
1963 -- so perform the transformation now.
1965 if SPARK_Mode = On and then In_Inlined_Body then
1967 Subp : constant Entity_Id := Entity (Selector_Name (P));
1968 Typ : constant Entity_Id := Etype (Prefix (P));
1971 if Is_Tagged_Type (Typ)
1972 and then Present (First_Formal (Subp))
1973 and then (Etype (First_Formal (Subp)) = Typ
1975 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1976 and then Try_Object_Operation (P)
1981 Analyze_Call_And_Resolve;
1986 Analyze_Call_And_Resolve;
1989 elsif Nkind (P) = N_Selected_Component
1990 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1991 and then Present (Actuals)
1992 and then No (Next (First (Actuals)))
1994 -- Can be call to parameterless entry family. What appears to be the
1995 -- sole argument is in fact the entry index. Rewrite prefix of node
1996 -- accordingly. Source representation is unchanged by this
2000 Make_Indexed_Component (Loc,
2001 Prefix => New_Copy (P),
2002 Expressions => Actuals);
2003 Set_Name (N, New_N);
2004 Set_Etype (New_N, Standard_Void_Type);
2005 Set_Parameter_Associations (N, No_List);
2006 Analyze_Call_And_Resolve;
2008 -- For the case of a reference to an element of an entry family, P is
2009 -- an indexed component whose prefix is a selected component (task and
2010 -- entry family), and whose index is the entry family index.
2012 elsif Nkind (P) = N_Indexed_Component
2013 and then Nkind (Prefix (P)) = N_Selected_Component
2014 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
2016 Analyze_Call_And_Resolve;
2018 -- If the prefix is the name of an entry family, it is a call from
2019 -- within the task body itself.
2021 elsif Nkind (P) = N_Indexed_Component
2022 and then Nkind (Prefix (P)) = N_Identifier
2023 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
2026 Make_Selected_Component (Loc,
2028 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
2029 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
2030 Rewrite (Prefix (P), New_N);
2032 Analyze_Call_And_Resolve;
2034 -- In Ada 2012. a qualified expression is a name, but it cannot be a
2035 -- procedure name, so the construct can only be a qualified expression.
2037 elsif Nkind (P) = N_Qualified_Expression
2038 and then Ada_Version >= Ada_2012
2040 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
2043 -- Anything else is an error
2046 Error_Msg_N ("invalid procedure or entry call", N);
2050 Restore_Ghost_Region (Saved_GM, Saved_IGR);
2051 end Analyze_Procedure_Call;
2053 ------------------------------
2054 -- Analyze_Return_Statement --
2055 ------------------------------
2057 procedure Analyze_Return_Statement (N : Node_Id) is
2058 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2059 N_Simple_Return_Statement));
2061 Returns_Object : constant Boolean :=
2062 Nkind (N) = N_Extended_Return_Statement
2064 (Nkind (N) = N_Simple_Return_Statement
2065 and then Present (Expression (N)));
2066 -- True if we're returning something; that is, "return <expression>;"
2067 -- or "return Result : T [:= ...]". False for "return;". Used for error
2068 -- checking: If Returns_Object is True, N should apply to a function
2069 -- body; otherwise N should apply to a procedure body, entry body,
2070 -- accept statement, or extended return statement.
2072 function Find_What_It_Applies_To return Entity_Id;
2073 -- Find the entity representing the innermost enclosing body, accept
2074 -- statement, or extended return statement. If the result is a callable
2075 -- construct or extended return statement, then this will be the value
2076 -- of the Return_Applies_To attribute. Otherwise, the program is
2077 -- illegal. See RM-6.5(4/2).
2079 -----------------------------
2080 -- Find_What_It_Applies_To --
2081 -----------------------------
2083 function Find_What_It_Applies_To return Entity_Id is
2084 Result : Entity_Id := Empty;
2087 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2088 -- and postconditions.
2090 for J in reverse 0 .. Scope_Stack.Last loop
2091 Result := Scope_Stack.Table (J).Entity;
2092 exit when not Ekind_In (Result, E_Block, E_Loop)
2093 and then Chars (Result) /= Name_uPostconditions;
2096 pragma Assert (Present (Result));
2098 end Find_What_It_Applies_To;
2100 -- Local declarations
2102 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2103 Kind : constant Entity_Kind := Ekind (Scope_Id);
2104 Loc : constant Source_Ptr := Sloc (N);
2105 Stm_Entity : constant Entity_Id :=
2107 (E_Return_Statement, Current_Scope, Loc, 'R');
2109 -- Start of processing for Analyze_Return_Statement
2112 Set_Return_Statement_Entity (N, Stm_Entity);
2114 Set_Etype (Stm_Entity, Standard_Void_Type);
2115 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2117 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2118 -- (4/2): an inner return statement will apply to this extended return.
2120 if Nkind (N) = N_Extended_Return_Statement then
2121 Push_Scope (Stm_Entity);
2124 -- Check that pragma No_Return is obeyed. Don't complain about the
2125 -- implicitly-generated return that is placed at the end.
2127 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2128 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2131 -- Warn on any unassigned OUT parameters if in procedure
2133 if Ekind (Scope_Id) = E_Procedure then
2134 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2137 -- Check that functions return objects, and other things do not
2139 if Kind = E_Function or else Kind = E_Generic_Function then
2140 if not Returns_Object then
2141 Error_Msg_N ("missing expression in return from function", N);
2144 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2145 if Returns_Object then
2146 Error_Msg_N ("procedure cannot return value (use function)", N);
2149 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2150 if Returns_Object then
2151 if Is_Protected_Type (Scope (Scope_Id)) then
2152 Error_Msg_N ("entry body cannot return value", N);
2154 Error_Msg_N ("accept statement cannot return value", N);
2158 elsif Kind = E_Return_Statement then
2160 -- We are nested within another return statement, which must be an
2161 -- extended_return_statement.
2163 if Returns_Object then
2164 if Nkind (N) = N_Extended_Return_Statement then
2166 ("extended return statement cannot be nested (use `RETURN;`)",
2169 -- Case of a simple return statement with a value inside extended
2170 -- return statement.
2174 ("return nested in extended return statement cannot return "
2175 & "value (use `RETURN;`)", N);
2180 Error_Msg_N ("illegal context for return statement", N);
2183 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2184 Analyze_Function_Return (N);
2186 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2187 Set_Return_Present (Scope_Id);
2190 if Nkind (N) = N_Extended_Return_Statement then
2194 Kill_Current_Values (Last_Assignment_Only => True);
2195 Check_Unreachable_Code (N);
2197 Analyze_Dimension (N);
2198 end Analyze_Return_Statement;
2200 -------------------------------------
2201 -- Analyze_Simple_Return_Statement --
2202 -------------------------------------
2204 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2206 if Present (Expression (N)) then
2207 Mark_Coextensions (N, Expression (N));
2210 Analyze_Return_Statement (N);
2211 end Analyze_Simple_Return_Statement;
2213 -------------------------
2214 -- Analyze_Return_Type --
2215 -------------------------
2217 procedure Analyze_Return_Type (N : Node_Id) is
2218 Designator : constant Entity_Id := Defining_Entity (N);
2219 Typ : Entity_Id := Empty;
2222 -- Normal case where result definition does not indicate an error
2224 if Result_Definition (N) /= Error then
2225 if Nkind (Result_Definition (N)) = N_Access_Definition then
2226 Check_SPARK_05_Restriction
2227 ("access result is not allowed", Result_Definition (N));
2229 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2232 AD : constant Node_Id :=
2233 Access_To_Subprogram_Definition (Result_Definition (N));
2235 if Present (AD) and then Protected_Present (AD) then
2236 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2238 Typ := Access_Definition (N, Result_Definition (N));
2242 Set_Parent (Typ, Result_Definition (N));
2243 Set_Is_Local_Anonymous_Access (Typ);
2244 Set_Etype (Designator, Typ);
2246 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2248 Null_Exclusion_Static_Checks (N);
2250 -- Subtype_Mark case
2253 Find_Type (Result_Definition (N));
2254 Typ := Entity (Result_Definition (N));
2255 Set_Etype (Designator, Typ);
2257 -- Unconstrained array as result is not allowed in SPARK
2259 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2260 Check_SPARK_05_Restriction
2261 ("returning an unconstrained array is not allowed",
2262 Result_Definition (N));
2265 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2267 Null_Exclusion_Static_Checks (N);
2269 -- If a null exclusion is imposed on the result type, then create
2270 -- a null-excluding itype (an access subtype) and use it as the
2271 -- function's Etype. Note that the null exclusion checks are done
2272 -- right before this, because they don't get applied to types that
2273 -- do not come from source.
2275 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2276 Set_Etype (Designator,
2277 Create_Null_Excluding_Itype
2280 Scope_Id => Scope (Current_Scope)));
2282 -- The new subtype must be elaborated before use because
2283 -- it is visible outside of the function. However its base
2284 -- type may not be frozen yet, so the reference that will
2285 -- force elaboration must be attached to the freezing of
2288 -- If the return specification appears on a proper body,
2289 -- the subtype will have been created already on the spec.
2291 if Is_Frozen (Typ) then
2292 if Nkind (Parent (N)) = N_Subprogram_Body
2293 and then Nkind (Parent (Parent (N))) = N_Subunit
2297 Build_Itype_Reference (Etype (Designator), Parent (N));
2301 Ensure_Freeze_Node (Typ);
2304 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2306 Set_Itype (IR, Etype (Designator));
2307 Append_Freeze_Actions (Typ, New_List (IR));
2312 Set_Etype (Designator, Typ);
2315 if Ekind (Typ) = E_Incomplete_Type
2316 or else (Is_Class_Wide_Type (Typ)
2317 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2319 -- AI05-0151: Tagged incomplete types are allowed in all formal
2320 -- parts. Untagged incomplete types are not allowed in bodies.
2321 -- As a consequence, limited views cannot appear in a basic
2322 -- declaration that is itself within a body, because there is
2323 -- no point at which the non-limited view will become visible.
2325 if Ada_Version >= Ada_2012 then
2326 if From_Limited_With (Typ) and then In_Package_Body then
2328 ("invalid use of incomplete type&",
2329 Result_Definition (N), Typ);
2331 -- The return type of a subprogram body cannot be of a
2332 -- formal incomplete type.
2334 elsif Is_Generic_Type (Typ)
2335 and then Nkind (Parent (N)) = N_Subprogram_Body
2338 ("return type cannot be a formal incomplete type",
2339 Result_Definition (N));
2341 elsif Is_Class_Wide_Type (Typ)
2342 and then Is_Generic_Type (Root_Type (Typ))
2343 and then Nkind (Parent (N)) = N_Subprogram_Body
2346 ("return type cannot be a formal incomplete type",
2347 Result_Definition (N));
2349 elsif Is_Tagged_Type (Typ) then
2352 -- Use is legal in a thunk generated for an operation
2353 -- inherited from a progenitor.
2355 elsif Is_Thunk (Designator)
2356 and then Present (Non_Limited_View (Typ))
2360 elsif Nkind (Parent (N)) = N_Subprogram_Body
2361 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2365 ("invalid use of untagged incomplete type&",
2369 -- The type must be completed in the current package. This
2370 -- is checked at the end of the package declaration when
2371 -- Taft-amendment types are identified. If the return type
2372 -- is class-wide, there is no required check, the type can
2373 -- be a bona fide TAT.
2375 if Ekind (Scope (Current_Scope)) = E_Package
2376 and then In_Private_Part (Scope (Current_Scope))
2377 and then not Is_Class_Wide_Type (Typ)
2379 Append_Elmt (Designator, Private_Dependents (Typ));
2384 ("invalid use of incomplete type&", Designator, Typ);
2389 -- Case where result definition does indicate an error
2392 Set_Etype (Designator, Any_Type);
2394 end Analyze_Return_Type;
2396 -----------------------------
2397 -- Analyze_Subprogram_Body --
2398 -----------------------------
2400 procedure Analyze_Subprogram_Body (N : Node_Id) is
2401 Loc : constant Source_Ptr := Sloc (N);
2402 Body_Spec : constant Node_Id := Specification (N);
2403 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2406 if Debug_Flag_C then
2407 Write_Str ("==> subprogram body ");
2408 Write_Name (Chars (Body_Id));
2409 Write_Str (" from ");
2410 Write_Location (Loc);
2415 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2417 -- The real work is split out into the helper, so it can do "return;"
2418 -- without skipping the debug output:
2420 Analyze_Subprogram_Body_Helper (N);
2422 if Debug_Flag_C then
2424 Write_Str ("<== subprogram body ");
2425 Write_Name (Chars (Body_Id));
2426 Write_Str (" from ");
2427 Write_Location (Loc);
2430 end Analyze_Subprogram_Body;
2432 ------------------------------------
2433 -- Analyze_Subprogram_Body_Helper --
2434 ------------------------------------
2436 -- This procedure is called for regular subprogram bodies, generic bodies,
2437 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2438 -- specification matters, and is used to create a proper declaration for
2439 -- the subprogram, or to perform conformance checks.
2441 -- WARNING: This routine manages Ghost regions. Return statements must be
2442 -- replaced by gotos that jump to the end of the routine and restore the
2445 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2446 Body_Spec : Node_Id := Specification (N);
2447 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2448 Loc : constant Source_Ptr := Sloc (N);
2449 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2451 Conformant : Boolean;
2452 Desig_View : Entity_Id := Empty;
2453 Exch_Views : Elist_Id := No_Elist;
2455 Mask_Types : Elist_Id := No_Elist;
2456 Prot_Typ : Entity_Id := Empty;
2457 Spec_Decl : Node_Id := Empty;
2458 Spec_Id : Entity_Id;
2460 Last_Real_Spec_Entity : Entity_Id := Empty;
2461 -- When we analyze a separate spec, the entity chain ends up containing
2462 -- the formals, as well as any itypes generated during analysis of the
2463 -- default expressions for parameters, or the arguments of associated
2464 -- precondition/postcondition pragmas (which are analyzed in the context
2465 -- of the spec since they have visibility on formals).
2467 -- These entities belong with the spec and not the body. However we do
2468 -- the analysis of the body in the context of the spec (again to obtain
2469 -- visibility to the formals), and all the entities generated during
2470 -- this analysis end up also chained to the entity chain of the spec.
2471 -- But they really belong to the body, and there is circuitry to move
2472 -- them from the spec to the body.
2474 -- However, when we do this move, we don't want to move the real spec
2475 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2476 -- variable points to the last real spec entity, so we only move those
2477 -- chained beyond that point. It is initialized to Empty to deal with
2478 -- the case where there is no separate spec.
2480 function Body_Has_Contract return Boolean;
2481 -- Check whether unanalyzed body has an aspect or pragma that may
2482 -- generate a SPARK contract.
2484 function Body_Has_SPARK_Mode_On return Boolean;
2485 -- Check whether SPARK_Mode On applies to the subprogram body, either
2486 -- because it is specified directly on the body, or because it is
2487 -- inherited from the enclosing subprogram or package.
2489 procedure Build_Subprogram_Declaration;
2490 -- Create a matching subprogram declaration for subprogram body N
2492 procedure Check_Anonymous_Return;
2493 -- Ada 2005: if a function returns an access type that denotes a task,
2494 -- or a type that contains tasks, we must create a master entity for
2495 -- the anonymous type, which typically will be used in an allocator
2496 -- in the body of the function.
2498 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2499 -- Look ahead to recognize a pragma that may appear after the body.
2500 -- If there is a previous spec, check that it appears in the same
2501 -- declarative part. If the pragma is Inline_Always, perform inlining
2502 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2503 -- If the body acts as a spec, and inlining is required, we create a
2504 -- subprogram declaration for it, in order to attach the body to inline.
2505 -- If pragma does not appear after the body, check whether there is
2506 -- an inline pragma before any local declarations.
2508 procedure Check_Missing_Return;
2509 -- Checks for a function with a no return statements, and also performs
2510 -- the warning checks implemented by Check_Returns. In formal mode, also
2511 -- verify that a function ends with a RETURN and that a procedure does
2512 -- not contain any RETURN.
2514 function Disambiguate_Spec return Entity_Id;
2515 -- When a primitive is declared between the private view and the full
2516 -- view of a concurrent type which implements an interface, a special
2517 -- mechanism is used to find the corresponding spec of the primitive
2520 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2521 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2522 -- incomplete types coming from a limited context and replace their
2523 -- limited views with the non-limited ones. Return the list of changes
2524 -- to be used to undo the transformation.
2526 function Is_Private_Concurrent_Primitive
2527 (Subp_Id : Entity_Id) return Boolean;
2528 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2529 -- type that implements an interface and has a private view.
2531 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2532 -- N is the body generated for an expression function that is not a
2533 -- completion and Spec_Id the defining entity of its spec. Mark all
2534 -- the not-yet-frozen types referenced by the simple return statement
2535 -- of the function as formally frozen.
2537 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2538 -- Undo the transformation done by Exchange_Limited_Views.
2540 procedure Set_Trivial_Subprogram (N : Node_Id);
2541 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2542 -- subprogram whose body is being analyzed. N is the statement node
2543 -- causing the flag to be set, if the following statement is a return
2544 -- of an entity, we mark the entity as set in source to suppress any
2545 -- warning on the stylized use of function stubs with a dummy return.
2547 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2548 -- Undo the transformation done by Mask_Unfrozen_Types
2550 procedure Verify_Overriding_Indicator;
2551 -- If there was a previous spec, the entity has been entered in the
2552 -- current scope previously. If the body itself carries an overriding
2553 -- indicator, check that it is consistent with the known status of the
2556 -----------------------
2557 -- Body_Has_Contract --
2558 -----------------------
2560 function Body_Has_Contract return Boolean is
2561 Decls : constant List_Id := Declarations (N);
2565 -- Check for aspects that may generate a contract
2567 if Present (Aspect_Specifications (N)) then
2568 Item := First (Aspect_Specifications (N));
2569 while Present (Item) loop
2570 if Is_Subprogram_Contract_Annotation (Item) then
2578 -- Check for pragmas that may generate a contract
2580 if Present (Decls) then
2581 Item := First (Decls);
2582 while Present (Item) loop
2583 if Nkind (Item) = N_Pragma
2584 and then Is_Subprogram_Contract_Annotation (Item)
2594 end Body_Has_Contract;
2596 ----------------------------
2597 -- Body_Has_SPARK_Mode_On --
2598 ----------------------------
2600 function Body_Has_SPARK_Mode_On return Boolean is
2601 Decls : constant List_Id := Declarations (N);
2605 -- Check for SPARK_Mode aspect
2607 if Present (Aspect_Specifications (N)) then
2608 Item := First (Aspect_Specifications (N));
2609 while Present (Item) loop
2610 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2611 return Get_SPARK_Mode_From_Annotation (Item) = On;
2618 -- Check for SPARK_Mode pragma
2620 if Present (Decls) then
2621 Item := First (Decls);
2622 while Present (Item) loop
2624 -- Pragmas that apply to a subprogram body are usually grouped
2625 -- together. Look for a potential pragma SPARK_Mode among them.
2627 if Nkind (Item) = N_Pragma then
2628 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2629 return Get_SPARK_Mode_From_Annotation (Item) = On;
2632 -- Otherwise the first non-pragma declarative item terminates
2633 -- the region where pragma SPARK_Mode may appear.
2643 -- Otherwise, the applicable SPARK_Mode is inherited from the
2644 -- enclosing subprogram or package.
2646 return SPARK_Mode = On;
2647 end Body_Has_SPARK_Mode_On;
2649 ----------------------------------
2650 -- Build_Subprogram_Declaration --
2651 ----------------------------------
2653 procedure Build_Subprogram_Declaration is
2654 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2655 -- Relocate certain categorization pragmas from the declarative list
2656 -- of subprogram body From and insert them after node To. The pragmas
2659 -- Volatile_Function
2660 -- Also copy pragma SPARK_Mode if present in the declarative list
2661 -- of subprogram body From and insert it after node To. This pragma
2662 -- should not be moved, as it applies to the body too.
2668 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2670 Next_Decl : Node_Id;
2673 pragma Assert (Nkind (From) = N_Subprogram_Body);
2675 -- The destination node must be part of a list, as the pragmas are
2676 -- inserted after it.
2678 pragma Assert (Is_List_Member (To));
2680 -- Inspect the declarations of the subprogram body looking for
2681 -- specific pragmas.
2683 Decl := First (Declarations (N));
2684 while Present (Decl) loop
2685 Next_Decl := Next (Decl);
2687 if Nkind (Decl) = N_Pragma then
2688 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2689 Insert_After (To, New_Copy_Tree (Decl));
2691 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2693 Name_Volatile_Function)
2696 Insert_After (To, Decl);
2707 Subp_Decl : Node_Id;
2709 -- Start of processing for Build_Subprogram_Declaration
2712 -- Create a matching subprogram spec using the profile of the body.
2713 -- The structure of the tree is identical, but has new entities for
2714 -- the defining unit name and formal parameters.
2717 Make_Subprogram_Declaration (Loc,
2718 Specification => Copy_Subprogram_Spec (Body_Spec));
2719 Set_Comes_From_Source (Subp_Decl, True);
2721 -- Also mark parameters as coming from source
2723 if Present (Parameter_Specifications (Specification (Subp_Decl))) then
2728 First (Parameter_Specifications (Specification (Subp_Decl)));
2730 while Present (Form) loop
2731 Set_Comes_From_Source (Defining_Identifier (Form), True);
2737 -- Relocate the aspects and relevant pragmas from the subprogram body
2738 -- to the generated spec because it acts as the initial declaration.
2740 Insert_Before (N, Subp_Decl);
2741 Move_Aspects (N, To => Subp_Decl);
2742 Move_Pragmas (N, To => Subp_Decl);
2744 -- Ensure that the generated corresponding spec and original body
2745 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2746 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2747 -- correctly set for local subprograms.
2749 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2751 Analyze (Subp_Decl);
2753 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2754 -- the body since the expander may generate calls using that entity.
2755 -- Required to ensure that Expand_Call rewrites calls to this
2756 -- function by calls to the built procedure.
2758 if Modify_Tree_For_C
2759 and then Nkind (Body_Spec) = N_Function_Specification
2761 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2763 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2764 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2765 Corresponding_Procedure
2766 (Defining_Entity (Specification (Subp_Decl))));
2769 -- Analyze any relocated source pragmas or pragmas created for aspect
2772 Decl := Next (Subp_Decl);
2773 while Present (Decl) loop
2775 -- Stop the search for pragmas once the body has been reached as
2776 -- this terminates the region where pragmas may appear.
2781 elsif Nkind (Decl) = N_Pragma then
2788 Spec_Id := Defining_Entity (Subp_Decl);
2789 Set_Corresponding_Spec (N, Spec_Id);
2791 -- Mark the generated spec as a source construct to ensure that all
2792 -- calls to it are properly registered in ALI files for GNATprove.
2794 Set_Comes_From_Source (Spec_Id, True);
2796 -- Ensure that the specs of the subprogram declaration and its body
2797 -- are identical, otherwise they will appear non-conformant due to
2798 -- rewritings in the default values of formal parameters.
2800 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2801 Set_Specification (N, Body_Spec);
2802 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2803 end Build_Subprogram_Declaration;
2805 ----------------------------
2806 -- Check_Anonymous_Return --
2807 ----------------------------
2809 procedure Check_Anonymous_Return is
2815 if Present (Spec_Id) then
2821 if Ekind (Scop) = E_Function
2822 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2823 and then not Is_Thunk (Scop)
2825 -- Skip internally built functions which handle the case of
2826 -- a null access (see Expand_Interface_Conversion)
2828 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2829 and then not Comes_From_Source (Parent (Scop)))
2831 and then (Has_Task (Designated_Type (Etype (Scop)))
2833 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2835 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2836 and then Expander_Active
2838 -- Avoid cases with no tasking support
2840 and then RTE_Available (RE_Current_Master)
2841 and then not Restriction_Active (No_Task_Hierarchy)
2844 Make_Object_Declaration (Loc,
2845 Defining_Identifier =>
2846 Make_Defining_Identifier (Loc, Name_uMaster),
2847 Constant_Present => True,
2848 Object_Definition =>
2849 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2851 Make_Explicit_Dereference (Loc,
2852 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2854 if Present (Declarations (N)) then
2855 Prepend (Decl, Declarations (N));
2857 Set_Declarations (N, New_List (Decl));
2860 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2861 Set_Has_Master_Entity (Scop);
2863 -- Now mark the containing scope as a task master
2866 while Nkind (Par) /= N_Compilation_Unit loop
2867 Par := Parent (Par);
2868 pragma Assert (Present (Par));
2870 -- If we fall off the top, we are at the outer level, and
2871 -- the environment task is our effective master, so nothing
2875 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2877 Set_Is_Task_Master (Par, True);
2882 end Check_Anonymous_Return;
2884 -------------------------
2885 -- Check_Inline_Pragma --
2886 -------------------------
2888 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2892 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2893 -- True when N is a pragma Inline or Inline_Always that applies
2894 -- to this subprogram.
2896 -----------------------
2897 -- Is_Inline_Pragma --
2898 -----------------------
2900 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2902 if Nkind (N) = N_Pragma
2904 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2905 or else (Pragma_Name_Unmapped (N) = Name_Inline
2907 (Front_End_Inlining or else Optimization_Level > 0)))
2908 and then Present (Pragma_Argument_Associations (N))
2911 Pragma_Arg : Node_Id :=
2912 Expression (First (Pragma_Argument_Associations (N)));
2914 if Nkind (Pragma_Arg) = N_Selected_Component then
2915 Pragma_Arg := Selector_Name (Pragma_Arg);
2918 return Chars (Pragma_Arg) = Chars (Body_Id);
2924 end Is_Inline_Pragma;
2926 -- Start of processing for Check_Inline_Pragma
2929 if not Expander_Active then
2933 if Is_List_Member (N)
2934 and then Present (Next (N))
2935 and then Is_Inline_Pragma (Next (N))
2939 elsif Nkind (N) /= N_Subprogram_Body_Stub
2940 and then Present (Declarations (N))
2941 and then Is_Inline_Pragma (First (Declarations (N)))
2943 Prag := First (Declarations (N));
2949 if Present (Prag) then
2950 if Present (Spec_Id) then
2951 if Is_List_Member (N)
2952 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2953 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2959 -- Create a subprogram declaration, to make treatment uniform.
2960 -- Make the sloc of the subprogram name that of the entity in
2961 -- the body, so that style checks find identical strings.
2964 Subp : constant Entity_Id :=
2965 Make_Defining_Identifier
2966 (Sloc (Body_Id), Chars (Body_Id));
2967 Decl : constant Node_Id :=
2968 Make_Subprogram_Declaration (Loc,
2970 New_Copy_Tree (Specification (N)));
2973 -- Link the body and the generated spec
2975 Set_Corresponding_Body (Decl, Body_Id);
2976 Set_Corresponding_Spec (N, Subp);
2978 Set_Defining_Unit_Name (Specification (Decl), Subp);
2980 -- To ensure proper coverage when body is inlined, indicate
2981 -- whether the subprogram comes from source.
2983 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2985 if Present (First_Formal (Body_Id)) then
2986 Plist := Copy_Parameter_List (Body_Id);
2987 Set_Parameter_Specifications
2988 (Specification (Decl), Plist);
2991 -- Move aspects to the new spec
2993 if Has_Aspects (N) then
2994 Move_Aspects (N, To => Decl);
2997 Insert_Before (N, Decl);
3000 Set_Has_Pragma_Inline (Subp);
3002 if Pragma_Name (Prag) = Name_Inline_Always then
3003 Set_Is_Inlined (Subp);
3004 Set_Has_Pragma_Inline_Always (Subp);
3007 -- Prior to copying the subprogram body to create a template
3008 -- for it for subsequent inlining, remove the pragma from
3009 -- the current body so that the copy that will produce the
3010 -- new body will start from a completely unanalyzed tree.
3012 if Nkind (Parent (Prag)) = N_Subprogram_Body then
3013 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
3020 end Check_Inline_Pragma;
3022 --------------------------
3023 -- Check_Missing_Return --
3024 --------------------------
3026 procedure Check_Missing_Return is
3028 Missing_Ret : Boolean;
3031 if Nkind (Body_Spec) = N_Function_Specification then
3032 if Present (Spec_Id) then
3038 if Return_Present (Id) then
3039 Check_Returns (HSS, 'F', Missing_Ret);
3042 Set_Has_Missing_Return (Id);
3045 -- Within a premature instantiation of a package with no body, we
3046 -- build completions of the functions therein, with a Raise
3047 -- statement. No point in complaining about a missing return in
3050 elsif Ekind (Id) = E_Function
3051 and then In_Instance
3052 and then Present (Statements (HSS))
3053 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3057 elsif Is_Generic_Subprogram (Id)
3058 or else not Is_Machine_Code_Subprogram (Id)
3060 Error_Msg_N ("missing RETURN statement in function body", N);
3063 -- If procedure with No_Return, check returns
3065 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3066 if Present (Spec_Id) then
3072 if No_Return (Id) then
3073 Check_Returns (HSS, 'P', Missing_Ret, Id);
3077 -- Special checks in SPARK mode
3079 if Nkind (Body_Spec) = N_Function_Specification then
3081 -- In SPARK mode, last statement of a function should be a return
3084 Stat : constant Node_Id := Last_Source_Statement (HSS);
3087 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3088 N_Extended_Return_Statement)
3090 Check_SPARK_05_Restriction
3091 ("last statement in function should be RETURN", Stat);
3095 -- In SPARK mode, verify that a procedure has no return
3097 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3098 if Present (Spec_Id) then
3104 -- Would be nice to point to return statement here, can we
3105 -- borrow the Check_Returns procedure here ???
3107 if Return_Present (Id) then
3108 Check_SPARK_05_Restriction
3109 ("procedure should not have RETURN", N);
3112 end Check_Missing_Return;
3114 -----------------------
3115 -- Disambiguate_Spec --
3116 -----------------------
3118 function Disambiguate_Spec return Entity_Id is
3119 Priv_Spec : Entity_Id;
3122 procedure Replace_Types (To_Corresponding : Boolean);
3123 -- Depending on the flag, replace the type of formal parameters of
3124 -- Body_Id if it is a concurrent type implementing interfaces with
3125 -- the corresponding record type or the other way around.
3127 procedure Replace_Types (To_Corresponding : Boolean) is
3129 Formal_Typ : Entity_Id;
3132 Formal := First_Formal (Body_Id);
3133 while Present (Formal) loop
3134 Formal_Typ := Etype (Formal);
3136 if Is_Class_Wide_Type (Formal_Typ) then
3137 Formal_Typ := Root_Type (Formal_Typ);
3140 -- From concurrent type to corresponding record
3142 if To_Corresponding then
3143 if Is_Concurrent_Type (Formal_Typ)
3144 and then Present (Corresponding_Record_Type (Formal_Typ))
3147 (Corresponding_Record_Type (Formal_Typ)))
3150 Corresponding_Record_Type (Formal_Typ));
3153 -- From corresponding record to concurrent type
3156 if Is_Concurrent_Record_Type (Formal_Typ)
3157 and then Present (Interfaces (Formal_Typ))
3160 Corresponding_Concurrent_Type (Formal_Typ));
3164 Next_Formal (Formal);
3168 -- Start of processing for Disambiguate_Spec
3171 -- Try to retrieve the specification of the body as is. All error
3172 -- messages are suppressed because the body may not have a spec in
3173 -- its current state.
3175 Spec_N := Find_Corresponding_Spec (N, False);
3177 -- It is possible that this is the body of a primitive declared
3178 -- between a private and a full view of a concurrent type. The
3179 -- controlling parameter of the spec carries the concurrent type,
3180 -- not the corresponding record type as transformed by Analyze_
3181 -- Subprogram_Specification. In such cases, we undo the change
3182 -- made by the analysis of the specification and try to find the
3185 -- Note that wrappers already have their corresponding specs and
3186 -- bodies set during their creation, so if the candidate spec is
3187 -- a wrapper, then we definitely need to swap all types to their
3188 -- original concurrent status.
3191 or else Is_Primitive_Wrapper (Spec_N)
3193 -- Restore all references of corresponding record types to the
3194 -- original concurrent types.
3196 Replace_Types (To_Corresponding => False);
3197 Priv_Spec := Find_Corresponding_Spec (N, False);
3199 -- The current body truly belongs to a primitive declared between
3200 -- a private and a full view. We leave the modified body as is,
3201 -- and return the true spec.
3203 if Present (Priv_Spec)
3204 and then Is_Private_Primitive (Priv_Spec)
3209 -- In case that this is some sort of error, restore the original
3210 -- state of the body.
3212 Replace_Types (To_Corresponding => True);
3216 end Disambiguate_Spec;
3218 ----------------------------
3219 -- Exchange_Limited_Views --
3220 ----------------------------
3222 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3223 Result : Elist_Id := No_Elist;
3225 procedure Detect_And_Exchange (Id : Entity_Id);
3226 -- Determine whether Id's type denotes an incomplete type associated
3227 -- with a limited with clause and exchange the limited view with the
3228 -- non-limited one when available. Note that the non-limited view
3229 -- may exist because of a with_clause in another unit in the context,
3230 -- but cannot be used because the current view of the enclosing unit
3231 -- is still a limited view.
3233 -------------------------
3234 -- Detect_And_Exchange --
3235 -------------------------
3237 procedure Detect_And_Exchange (Id : Entity_Id) is
3238 Typ : constant Entity_Id := Etype (Id);
3240 if From_Limited_With (Typ)
3241 and then Has_Non_Limited_View (Typ)
3242 and then not From_Limited_With (Scope (Typ))
3245 Result := New_Elmt_List;
3248 Prepend_Elmt (Typ, Result);
3249 Prepend_Elmt (Id, Result);
3250 Set_Etype (Id, Non_Limited_View (Typ));
3252 end Detect_And_Exchange;
3258 -- Start of processing for Exchange_Limited_Views
3261 -- Do not process subprogram bodies as they already use the non-
3262 -- limited view of types.
3264 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3268 -- Examine all formals and swap views when applicable
3270 Formal := First_Formal (Subp_Id);
3271 while Present (Formal) loop
3272 Detect_And_Exchange (Formal);
3274 Next_Formal (Formal);
3277 -- Process the return type of a function
3279 if Ekind (Subp_Id) = E_Function then
3280 Detect_And_Exchange (Subp_Id);
3284 end Exchange_Limited_Views;
3286 -------------------------------------
3287 -- Is_Private_Concurrent_Primitive --
3288 -------------------------------------
3290 function Is_Private_Concurrent_Primitive
3291 (Subp_Id : Entity_Id) return Boolean
3293 Formal_Typ : Entity_Id;
3296 if Present (First_Formal (Subp_Id)) then
3297 Formal_Typ := Etype (First_Formal (Subp_Id));
3299 if Is_Concurrent_Record_Type (Formal_Typ) then
3300 if Is_Class_Wide_Type (Formal_Typ) then
3301 Formal_Typ := Root_Type (Formal_Typ);
3304 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3307 -- The type of the first formal is a concurrent tagged type with
3311 Is_Concurrent_Type (Formal_Typ)
3312 and then Is_Tagged_Type (Formal_Typ)
3313 and then Has_Private_Declaration (Formal_Typ);
3317 end Is_Private_Concurrent_Primitive;
3319 -------------------------
3320 -- Mask_Unfrozen_Types --
3321 -------------------------
3323 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3324 Result : Elist_Id := No_Elist;
3326 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3327 -- Mask all types referenced in the subtree rooted at Node
3329 --------------------
3330 -- Mask_Type_Refs --
3331 --------------------
3333 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3334 procedure Mask_Type (Typ : Entity_Id);
3335 -- ??? what does this do?
3341 procedure Mask_Type (Typ : Entity_Id) is
3343 -- Skip Itypes created by the preanalysis
3346 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3351 if not Is_Frozen (Typ) then
3352 if Scope (Typ) /= Current_Scope then
3353 Set_Is_Frozen (Typ);
3354 Append_New_Elmt (Typ, Result);
3356 Freeze_Before (N, Typ);
3361 -- Start of processing for Mask_Type_Refs
3364 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3365 Mask_Type (Etype (Entity (Node)));
3367 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3368 Mask_Type (Scope (Entity (Node)));
3371 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3372 and then Present (Etype (Node))
3374 Mask_Type (Etype (Node));
3380 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3384 Return_Stmt : constant Node_Id :=
3385 First (Statements (Handled_Statement_Sequence (N)));
3387 -- Start of processing for Mask_Unfrozen_Types
3390 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3392 Mask_References (Expression (Return_Stmt));
3395 end Mask_Unfrozen_Types;
3397 ---------------------------
3398 -- Restore_Limited_Views --
3399 ---------------------------
3401 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3402 Elmt : Elmt_Id := First_Elmt (Restore_List);
3406 while Present (Elmt) loop
3409 Set_Etype (Id, Node (Elmt));
3412 end Restore_Limited_Views;
3414 ----------------------------
3415 -- Set_Trivial_Subprogram --
3416 ----------------------------
3418 procedure Set_Trivial_Subprogram (N : Node_Id) is
3419 Nxt : constant Node_Id := Next (N);
3422 Set_Is_Trivial_Subprogram (Body_Id);
3424 if Present (Spec_Id) then
3425 Set_Is_Trivial_Subprogram (Spec_Id);
3429 and then Nkind (Nxt) = N_Simple_Return_Statement
3430 and then No (Next (Nxt))
3431 and then Present (Expression (Nxt))
3432 and then Is_Entity_Name (Expression (Nxt))
3434 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3436 end Set_Trivial_Subprogram;
3438 ---------------------------
3439 -- Unmask_Unfrozen_Types --
3440 ---------------------------
3442 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3443 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3446 while Present (Elmt) loop
3447 Set_Is_Frozen (Node (Elmt), False);
3450 end Unmask_Unfrozen_Types;
3452 ---------------------------------
3453 -- Verify_Overriding_Indicator --
3454 ---------------------------------
3456 procedure Verify_Overriding_Indicator is
3458 if Must_Override (Body_Spec) then
3459 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3460 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3464 -- Overridden controlled primitives may have had their
3465 -- Overridden_Operation field cleared according to the setting of
3466 -- the Is_Hidden flag. An issue arises, however, when analyzing
3467 -- an instance that may have manipulated the flag during
3468 -- expansion. As a result, we add an exception for this case.
3470 elsif not Present (Overridden_Operation (Spec_Id))
3471 and then not (Nam_In (Chars (Spec_Id), Name_Adjust,
3474 and then In_Instance)
3477 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3479 -- Overriding indicators aren't allowed for protected subprogram
3480 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3481 -- this to a warning if -gnatd.E is enabled.
3483 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3484 Error_Msg_Warn := Error_To_Warning;
3486 ("<<overriding indicator not allowed for protected "
3487 & "subprogram body", Body_Spec);
3490 elsif Must_Not_Override (Body_Spec) then
3491 if Present (Overridden_Operation (Spec_Id)) then
3493 ("subprogram& overrides inherited operation",
3494 Body_Spec, Spec_Id);
3496 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3497 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3500 ("subprogram& overrides predefined operator ",
3501 Body_Spec, Spec_Id);
3503 -- Overriding indicators aren't allowed for protected subprogram
3504 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3505 -- this to a warning if -gnatd.E is enabled.
3507 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3508 Error_Msg_Warn := Error_To_Warning;
3511 ("<<overriding indicator not allowed "
3512 & "for protected subprogram body", Body_Spec);
3514 -- If this is not a primitive operation, then the overriding
3515 -- indicator is altogether illegal.
3517 elsif not Is_Primitive (Spec_Id) then
3519 ("overriding indicator only allowed "
3520 & "if subprogram is primitive", Body_Spec);
3523 -- If checking the style rule and the operation overrides, then
3524 -- issue a warning about a missing overriding_indicator. Protected
3525 -- subprogram bodies are excluded from this style checking, since
3526 -- they aren't primitives (even though their declarations can
3527 -- override) and aren't allowed to have an overriding_indicator.
3530 and then Present (Overridden_Operation (Spec_Id))
3531 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3533 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3534 Style.Missing_Overriding (N, Body_Id);
3537 and then Can_Override_Operator (Spec_Id)
3538 and then not In_Predefined_Unit (Spec_Id)
3540 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3541 Style.Missing_Overriding (N, Body_Id);
3543 end Verify_Overriding_Indicator;
3547 Body_Nod : Node_Id := Empty;
3548 Minimum_Acc_Objs : List_Id := No_List;
3550 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3551 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3552 Saved_EA : constant Boolean := Expander_Active;
3553 Saved_ISMP : constant Boolean :=
3554 Ignore_SPARK_Mode_Pragmas_In_Instance;
3555 -- Save the Ghost and SPARK mode-related data to restore on exit
3557 -- Start of processing for Analyze_Subprogram_Body_Helper
3560 -- A [generic] subprogram body freezes the contract of the nearest
3561 -- enclosing package body and all other contracts encountered in the
3562 -- same declarative part up to and excluding the subprogram body:
3564 -- package body Nearest_Enclosing_Package
3565 -- with Refined_State => (State => Constit)
3569 -- procedure Freezes_Enclosing_Package_Body
3570 -- with Refined_Depends => (Input => Constit) ...
3572 -- This ensures that any annotations referenced by the contract of the
3573 -- [generic] subprogram body are available. This form of freezing is
3574 -- decoupled from the usual Freeze_xxx mechanism because it must also
3575 -- work in the context of generics where normal freezing is disabled.
3577 -- Only bodies coming from source should cause this type of freezing.
3578 -- Expression functions that act as bodies and complete an initial
3579 -- declaration must be included in this category, hence the use of
3582 if Comes_From_Source (Original_Node (N)) then
3583 Freeze_Previous_Contracts (N);
3586 -- Generic subprograms are handled separately. They always have a
3587 -- generic specification. Determine whether current scope has a
3588 -- previous declaration.
3590 -- If the subprogram body is defined within an instance of the same
3591 -- name, the instance appears as a package renaming, and will be hidden
3592 -- within the subprogram.
3594 if Present (Prev_Id)
3595 and then not Is_Overloadable (Prev_Id)
3596 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3597 or else Comes_From_Source (Prev_Id))
3599 if Is_Generic_Subprogram (Prev_Id) then
3602 -- A subprogram body is Ghost when it is stand-alone and subject
3603 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3604 -- the mode now to ensure that any nodes generated during analysis
3605 -- and expansion are properly marked as Ghost.
3607 Mark_And_Set_Ghost_Body (N, Spec_Id);
3609 -- If the body completes the initial declaration of a compilation
3610 -- unit which is subject to pragma Elaboration_Checks, set the
3611 -- model specified by the pragma because it applies to all parts
3614 Install_Elaboration_Model (Spec_Id);
3616 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3617 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3619 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3621 if Nkind (N) = N_Subprogram_Body then
3622 HSS := Handled_Statement_Sequence (N);
3623 Check_Missing_Return;
3628 -- Otherwise a previous entity conflicts with the subprogram name.
3629 -- Attempting to enter name will post error.
3632 Enter_Name (Body_Id);
3636 -- Non-generic case, find the subprogram declaration, if one was seen,
3637 -- or enter new overloaded entity in the current scope. If the
3638 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3639 -- part of the context of one of its subunits. No need to redo the
3642 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3646 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3648 if Nkind (N) = N_Subprogram_Body_Stub
3649 or else No (Corresponding_Spec (N))
3651 if Is_Private_Concurrent_Primitive (Body_Id) then
3652 Spec_Id := Disambiguate_Spec;
3654 -- A subprogram body is Ghost when it is stand-alone and
3655 -- subject to pragma Ghost or when the corresponding spec is
3656 -- Ghost. Set the mode now to ensure that any nodes generated
3657 -- during analysis and expansion are properly marked as Ghost.
3659 Mark_And_Set_Ghost_Body (N, Spec_Id);
3661 -- If the body completes a compilation unit which is subject
3662 -- to pragma Elaboration_Checks, set the model specified by
3663 -- the pragma because it applies to all parts of the unit.
3665 Install_Elaboration_Model (Spec_Id);
3668 Spec_Id := Find_Corresponding_Spec (N);
3670 -- A subprogram body is Ghost when it is stand-alone and
3671 -- subject to pragma Ghost or when the corresponding spec is
3672 -- Ghost. Set the mode now to ensure that any nodes generated
3673 -- during analysis and expansion are properly marked as Ghost.
3675 Mark_And_Set_Ghost_Body (N, Spec_Id);
3677 -- If the body completes a compilation unit which is subject
3678 -- to pragma Elaboration_Checks, set the model specified by
3679 -- the pragma because it applies to all parts of the unit.
3681 Install_Elaboration_Model (Spec_Id);
3683 -- In GNATprove mode, if the body has no previous spec, create
3684 -- one so that the inlining machinery can operate properly.
3685 -- Transfer aspects, if any, to the new spec, so that they
3686 -- are legal and can be processed ahead of the body.
3687 -- We make two copies of the given spec, one for the new
3688 -- declaration, and one for the body.
3690 if No (Spec_Id) and then GNATprove_Mode
3692 -- Inlining does not apply during preanalysis of code
3694 and then Full_Analysis
3696 -- Inlining only applies to full bodies, not stubs
3698 and then Nkind (N) /= N_Subprogram_Body_Stub
3700 -- Inlining only applies to bodies in the source code, not to
3701 -- those generated by the compiler. In particular, expression
3702 -- functions, whose body is generated by the compiler, are
3703 -- treated specially by GNATprove.
3705 and then Comes_From_Source (Body_Id)
3707 -- This cannot be done for a compilation unit, which is not
3708 -- in a context where we can insert a new spec.
3710 and then Is_List_Member (N)
3712 -- Inlining only applies to subprograms without contracts,
3713 -- as a contract is a sign that GNATprove should perform a
3714 -- modular analysis of the subprogram instead of a contextual
3715 -- analysis at each call site. The same test is performed in
3716 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3717 -- here in another form (because the contract has not been
3718 -- attached to the body) to avoid front-end errors in case
3719 -- pragmas are used instead of aspects, because the
3720 -- corresponding pragmas in the body would not be transferred
3721 -- to the spec, leading to legality errors.
3723 and then not Body_Has_Contract
3724 and then not Inside_A_Generic
3726 Build_Subprogram_Declaration;
3728 -- If this is a function that returns a constrained array, and
3729 -- we are generating SPARK_For_C, create subprogram declaration
3730 -- to simplify subsequent C generation.
3733 and then Modify_Tree_For_C
3734 and then Nkind (Body_Spec) = N_Function_Specification
3735 and then Is_Array_Type (Etype (Body_Id))
3736 and then Is_Constrained (Etype (Body_Id))
3738 Build_Subprogram_Declaration;
3742 -- If this is a duplicate body, no point in analyzing it
3744 if Error_Posted (N) then
3748 -- A subprogram body should cause freezing of its own declaration,
3749 -- but if there was no previous explicit declaration, then the
3750 -- subprogram will get frozen too late (there may be code within
3751 -- the body that depends on the subprogram having been frozen,
3752 -- such as uses of extra formals), so we force it to be frozen
3753 -- here. Same holds if the body and spec are compilation units.
3754 -- Finally, if the return type is an anonymous access to protected
3755 -- subprogram, it must be frozen before the body because its
3756 -- expansion has generated an equivalent type that is used when
3757 -- elaborating the body.
3759 -- An exception in the case of Ada 2012, AI05-177: The bodies
3760 -- created for expression functions do not freeze.
3763 and then Nkind (Original_Node (N)) /= N_Expression_Function
3765 Freeze_Before (N, Body_Id);
3767 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3768 Freeze_Before (N, Spec_Id);
3770 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3771 Freeze_Before (N, Etype (Body_Id));
3775 Spec_Id := Corresponding_Spec (N);
3777 -- A subprogram body is Ghost when it is stand-alone and subject
3778 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3779 -- the mode now to ensure that any nodes generated during analysis
3780 -- and expansion are properly marked as Ghost.
3782 Mark_And_Set_Ghost_Body (N, Spec_Id);
3784 -- If the body completes the initial declaration of a compilation
3785 -- unit which is subject to pragma Elaboration_Checks, set the
3786 -- model specified by the pragma because it applies to all parts
3789 Install_Elaboration_Model (Spec_Id);
3793 -- Deactivate expansion inside the body of ignored Ghost entities,
3794 -- as this code will ultimately be ignored. This avoids requiring the
3795 -- presence of run-time units which are not needed. Only do this for
3796 -- user entities, as internally generated entitities might still need
3797 -- to be expanded (e.g. those generated for types).
3799 if Present (Ignored_Ghost_Region)
3800 and then Comes_From_Source (Body_Id)
3802 Expander_Active := False;
3805 -- Previously we scanned the body to look for nested subprograms, and
3806 -- rejected an inline directive if nested subprograms were present,
3807 -- because the back-end would generate conflicting symbols for the
3808 -- nested bodies. This is now unnecessary.
3810 -- Look ahead to recognize a pragma Inline that appears after the body
3812 Check_Inline_Pragma (Spec_Id);
3814 -- Deal with special case of a fully private operation in the body of
3815 -- the protected type. We must create a declaration for the subprogram,
3816 -- in order to attach the protected subprogram that will be used in
3817 -- internal calls. We exclude compiler generated bodies from the
3818 -- expander since the issue does not arise for those cases.
3821 and then Comes_From_Source (N)
3822 and then Is_Protected_Type (Current_Scope)
3824 Spec_Id := Build_Private_Protected_Declaration (N);
3827 -- If we are generating C and this is a function returning a constrained
3828 -- array type for which we must create a procedure with an extra out
3829 -- parameter, build and analyze the body now. The procedure declaration
3830 -- has already been created. We reuse the source body of the function,
3831 -- because in an instance it may contain global references that cannot
3832 -- be reanalyzed. The source function itself is not used any further,
3833 -- so we mark it as having a completion. If the subprogram is a stub the
3834 -- transformation is done later, when the proper body is analyzed.
3837 and then Modify_Tree_For_C
3838 and then Present (Spec_Id)
3839 and then Ekind (Spec_Id) = E_Function
3840 and then Nkind (N) /= N_Subprogram_Body_Stub
3841 and then Rewritten_For_C (Spec_Id)
3843 Set_Has_Completion (Spec_Id);
3845 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3848 -- The entity for the created procedure must remain invisible, so it
3849 -- does not participate in resolution of subsequent references to the
3852 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3856 -- If a separate spec is present, then deal with freezing issues
3858 if Present (Spec_Id) then
3859 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3860 Verify_Overriding_Indicator;
3862 -- In general, the spec will be frozen when we start analyzing the
3863 -- body. However, for internally generated operations, such as
3864 -- wrapper functions for inherited operations with controlling
3865 -- results, the spec may not have been frozen by the time we expand
3866 -- the freeze actions that include the bodies. In particular, extra
3867 -- formals for accessibility or for return-in-place may need to be
3868 -- generated. Freeze nodes, if any, are inserted before the current
3869 -- body. These freeze actions are also needed in Compile_Only mode to
3870 -- enable the proper back-end type annotations.
3871 -- They are necessary in any case to ensure proper elaboration order
3874 if Nkind (N) = N_Subprogram_Body
3875 and then Was_Expression_Function (N)
3876 and then not Has_Completion (Spec_Id)
3877 and then Serious_Errors_Detected = 0
3878 and then (Expander_Active
3879 or else Operating_Mode = Check_Semantics
3880 or else Is_Ignored_Ghost_Entity (Spec_Id))
3882 -- The body generated for an expression function that is not a
3883 -- completion is a freeze point neither for the profile nor for
3884 -- anything else. That's why, in order to prevent any freezing
3885 -- during analysis, we need to mask types declared outside the
3886 -- expression (and in an outer scope) that are not yet frozen.
3887 -- This also needs to be done in the case of an ignored Ghost
3888 -- expression function, where the expander isn't active.
3890 Set_Is_Frozen (Spec_Id);
3891 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3893 elsif not Is_Frozen (Spec_Id)
3894 and then Serious_Errors_Detected = 0
3896 Set_Has_Delayed_Freeze (Spec_Id);
3897 Freeze_Before (N, Spec_Id);
3901 -- If the subprogram has a class-wide clone, build its body as a copy
3902 -- of the original body, and rewrite body of original subprogram as a
3903 -- wrapper that calls the clone. If N is a stub, this construction will
3904 -- take place when the proper body is analyzed. No action needed if this
3905 -- subprogram has been eliminated.
3907 if Present (Spec_Id)
3908 and then Present (Class_Wide_Clone (Spec_Id))
3909 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3910 and then Nkind (N) /= N_Subprogram_Body_Stub
3911 and then not (Expander_Active and then Is_Eliminated (Spec_Id))
3913 Build_Class_Wide_Clone_Body (Spec_Id, N);
3915 -- This is the new body for the existing primitive operation
3917 Rewrite (N, Build_Class_Wide_Clone_Call
3918 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3919 Set_Has_Completion (Spec_Id, False);
3924 -- Place subprogram on scope stack, and make formals visible. If there
3925 -- is a spec, the visible entity remains that of the spec.
3927 if Present (Spec_Id) then
3928 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3930 if Is_Child_Unit (Spec_Id) then
3931 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3935 Style.Check_Identifier (Body_Id, Spec_Id);
3938 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3939 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3941 if Is_Abstract_Subprogram (Spec_Id) then
3942 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3946 Set_Convention (Body_Id, Convention (Spec_Id));
3947 Set_Has_Completion (Spec_Id);
3949 if Is_Protected_Type (Scope (Spec_Id)) then
3950 Prot_Typ := Scope (Spec_Id);
3953 -- If this is a body generated for a renaming, do not check for
3954 -- full conformance. The check is redundant, because the spec of
3955 -- the body is a copy of the spec in the renaming declaration,
3956 -- and the test can lead to spurious errors on nested defaults.
3958 if Present (Spec_Decl)
3959 and then not Comes_From_Source (N)
3961 (Nkind (Original_Node (Spec_Decl)) =
3962 N_Subprogram_Renaming_Declaration
3963 or else (Present (Corresponding_Body (Spec_Decl))
3965 Nkind (Unit_Declaration_Node
3966 (Corresponding_Body (Spec_Decl))) =
3967 N_Subprogram_Renaming_Declaration))
3971 -- Conversely, the spec may have been generated for specless body
3972 -- with an inline pragma. The entity comes from source, which is
3973 -- both semantically correct and necessary for proper inlining.
3974 -- The subprogram declaration itself is not in the source.
3976 elsif Comes_From_Source (N)
3977 and then Present (Spec_Decl)
3978 and then not Comes_From_Source (Spec_Decl)
3979 and then Has_Pragma_Inline (Spec_Id)
3986 Fully_Conformant, True, Conformant, Body_Id);
3989 -- If the body is not fully conformant, we have to decide if we
3990 -- should analyze it or not. If it has a really messed up profile
3991 -- then we probably should not analyze it, since we will get too
3992 -- many bogus messages.
3994 -- Our decision is to go ahead in the non-fully conformant case
3995 -- only if it is at least mode conformant with the spec. Note
3996 -- that the call to Check_Fully_Conformant has issued the proper
3997 -- error messages to complain about the lack of conformance.
4000 and then not Mode_Conformant (Body_Id, Spec_Id)
4006 -- In the case we are dealing with an expression function we check
4007 -- the formals attached to the spec instead of the body - so we don't
4008 -- reference body formals.
4010 if Spec_Id /= Body_Id
4011 and then not Is_Expression_Function (Spec_Id)
4013 Reference_Body_Formals (Spec_Id, Body_Id);
4016 Set_Ekind (Body_Id, E_Subprogram_Body);
4018 if Nkind (N) = N_Subprogram_Body_Stub then
4019 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
4024 Set_Corresponding_Spec (N, Spec_Id);
4026 -- Ada 2005 (AI-345): If the operation is a primitive operation
4027 -- of a concurrent type, the type of the first parameter has been
4028 -- replaced with the corresponding record, which is the proper
4029 -- run-time structure to use. However, within the body there may
4030 -- be uses of the formals that depend on primitive operations
4031 -- of the type (in particular calls in prefixed form) for which
4032 -- we need the original concurrent type. The operation may have
4033 -- several controlling formals, so the replacement must be done
4036 if Comes_From_Source (Spec_Id)
4037 and then Present (First_Entity (Spec_Id))
4038 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
4039 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
4040 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
4041 and then Present (Corresponding_Concurrent_Type
4042 (Etype (First_Entity (Spec_Id))))
4045 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
4049 Form := First_Formal (Spec_Id);
4050 while Present (Form) loop
4051 if Etype (Form) = Typ then
4052 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
4060 -- Make the formals visible, and place subprogram on scope stack.
4061 -- This is also the point at which we set Last_Real_Spec_Entity
4062 -- to mark the entities which will not be moved to the body.
4064 Install_Formals (Spec_Id);
4065 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
4067 -- Within an instance, add local renaming declarations so that
4068 -- gdb can retrieve the values of actuals more easily. This is
4069 -- only relevant if generating code.
4071 if Is_Generic_Instance (Spec_Id)
4072 and then Is_Wrapper_Package (Current_Scope)
4073 and then Expander_Active
4075 Build_Subprogram_Instance_Renamings (N, Current_Scope);
4078 Push_Scope (Spec_Id);
4080 -- Make sure that the subprogram is immediately visible. For
4081 -- child units that have no separate spec this is indispensable.
4082 -- Otherwise it is safe albeit redundant.
4084 Set_Is_Immediately_Visible (Spec_Id);
4087 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
4088 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
4089 Set_Scope (Body_Id, Scope (Spec_Id));
4091 -- Case of subprogram body with no previous spec
4094 -- Check for style warning required
4098 -- Only apply check for source level subprograms for which checks
4099 -- have not been suppressed.
4101 and then Comes_From_Source (Body_Id)
4102 and then not Suppress_Style_Checks (Body_Id)
4104 -- No warnings within an instance
4106 and then not In_Instance
4108 -- No warnings for expression functions
4110 and then Nkind (Original_Node (N)) /= N_Expression_Function
4112 Style.Body_With_No_Spec (N);
4115 New_Overloaded_Entity (Body_Id);
4117 if Nkind (N) /= N_Subprogram_Body_Stub then
4118 Set_Acts_As_Spec (N);
4119 Generate_Definition (Body_Id);
4121 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
4123 -- If the body is an entry wrapper created for an entry with
4124 -- preconditions, it must be compiled in the context of the
4125 -- enclosing synchronized object, because it may mention other
4126 -- operations of the type.
4128 if Is_Entry_Wrapper (Body_Id) then
4130 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4133 Install_Declarations (Prot);
4137 Install_Formals (Body_Id);
4139 Push_Scope (Body_Id);
4142 -- For stubs and bodies with no previous spec, generate references to
4145 Generate_Reference_To_Formals (Body_Id);
4148 -- Entry barrier functions are generated outside the protected type and
4149 -- should not carry the SPARK_Mode of the enclosing context.
4151 if Nkind (N) = N_Subprogram_Body
4152 and then Is_Entry_Barrier_Function (N)
4156 -- The body is generated as part of expression function expansion. When
4157 -- the expression function appears in the visible declarations of a
4158 -- package, the body is added to the private declarations. Since both
4159 -- declarative lists may be subject to a different SPARK_Mode, inherit
4160 -- the mode of the spec.
4162 -- package P with SPARK_Mode is
4163 -- function Expr_Func ... is (...); -- original
4164 -- [function Expr_Func ...;] -- generated spec
4167 -- pragma SPARK_Mode (Off);
4168 -- [function Expr_Func ... is return ...;] -- generated body
4169 -- end P; -- mode is ON
4171 elsif not Comes_From_Source (N)
4172 and then Present (Spec_Id)
4173 and then Is_Expression_Function (Spec_Id)
4175 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4176 Set_SPARK_Pragma_Inherited
4177 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4179 -- Set the SPARK_Mode from the current context (may be overwritten later
4180 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4181 -- initially on a stand-alone subprogram body, but is then relocated to
4182 -- a generated corresponding spec. In this scenario the mode is shared
4183 -- between the spec and body.
4185 elsif No (SPARK_Pragma (Body_Id)) then
4186 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4187 Set_SPARK_Pragma_Inherited (Body_Id);
4190 -- A subprogram body may be instantiated or inlined at a later pass.
4191 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4192 -- applied to the initial declaration of the body.
4194 if Present (Spec_Id) then
4195 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4196 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4200 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4201 -- case the body is instantiated or inlined later and out of context.
4202 -- The body uses this attribute to restore the value of the global
4205 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4206 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4208 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4209 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4213 -- Preserve relevant elaboration-related attributes of the context which
4214 -- are no longer available or very expensive to recompute once analysis,
4215 -- resolution, and expansion are over.
4217 if No (Spec_Id) then
4218 Mark_Elaboration_Attributes
4224 -- If this is the proper body of a stub, we must verify that the stub
4225 -- conforms to the body, and to the previous spec if one was present.
4226 -- We know already that the body conforms to that spec. This test is
4227 -- only required for subprograms that come from source.
4229 if Nkind (Parent (N)) = N_Subunit
4230 and then Comes_From_Source (N)
4231 and then not Error_Posted (Body_Id)
4232 and then Nkind (Corresponding_Stub (Parent (N))) =
4233 N_Subprogram_Body_Stub
4236 Old_Id : constant Entity_Id :=
4238 (Specification (Corresponding_Stub (Parent (N))));
4240 Conformant : Boolean := False;
4243 if No (Spec_Id) then
4244 Check_Fully_Conformant (Body_Id, Old_Id);
4248 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4250 if not Conformant then
4252 -- The stub was taken to be a new declaration. Indicate that
4255 Set_Has_Completion (Old_Id, False);
4261 Set_Has_Completion (Body_Id);
4262 Check_Eliminated (Body_Id);
4264 -- Analyze any aspect specifications that appear on the subprogram body
4265 -- stub. Stop the analysis now as the stub does not have a declarative
4266 -- or a statement part, and it cannot be inlined.
4268 if Nkind (N) = N_Subprogram_Body_Stub then
4269 if Has_Aspects (N) then
4270 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4278 -- Note: Normally we don't do any inlining if expansion is off, since
4279 -- we won't generate code in any case. An exception arises in GNATprove
4280 -- mode where we want to expand some calls in place, even with expansion
4281 -- disabled, since the inlining eases formal verification.
4283 if not GNATprove_Mode
4284 and then Expander_Active
4285 and then Serious_Errors_Detected = 0
4286 and then Present (Spec_Id)
4287 and then Has_Pragma_Inline (Spec_Id)
4289 -- Legacy implementation (relying on front-end inlining)
4291 if not Back_End_Inlining then
4292 if (Has_Pragma_Inline_Always (Spec_Id)
4293 and then not Opt.Disable_FE_Inline_Always)
4294 or else (Front_End_Inlining
4295 and then not Opt.Disable_FE_Inline)
4297 Build_Body_To_Inline (N, Spec_Id);
4300 -- New implementation (relying on back-end inlining)
4303 if Has_Pragma_Inline_Always (Spec_Id)
4304 or else Optimization_Level > 0
4306 -- Handle function returning an unconstrained type
4308 if Comes_From_Source (Body_Id)
4309 and then Ekind (Spec_Id) = E_Function
4310 and then Returns_Unconstrained_Type (Spec_Id)
4312 -- If function builds in place, i.e. returns a limited type,
4313 -- inlining cannot be done.
4315 and then not Is_Limited_Type (Etype (Spec_Id))
4317 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4321 Subp_Body : constant Node_Id :=
4322 Unit_Declaration_Node (Body_Id);
4323 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4326 -- Do not pass inlining to the backend if the subprogram
4327 -- has declarations or statements which cannot be inlined
4328 -- by the backend. This check is done here to emit an
4329 -- error instead of the generic warning message reported
4330 -- by the GCC backend (ie. "function might not be
4333 if Present (Subp_Decl)
4334 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4338 elsif Has_Excluded_Statement
4341 (Handled_Statement_Sequence (Subp_Body)))
4345 -- If the backend inlining is available then at this
4346 -- stage we only have to mark the subprogram as inlined.
4347 -- The expander will take care of registering it in the
4348 -- table of subprograms inlined by the backend a part of
4349 -- processing calls to it (cf. Expand_Call)
4352 Set_Is_Inlined (Spec_Id);
4359 -- In GNATprove mode, inline only when there is a separate subprogram
4360 -- declaration for now, as inlining of subprogram bodies acting as
4361 -- declarations, or subprogram stubs, are not supported by front-end
4362 -- inlining. This inlining should occur after analysis of the body, so
4363 -- that it is known whether the value of SPARK_Mode, which can be
4364 -- defined by a pragma inside the body, is applicable to the body.
4365 -- Inlining can be disabled with switch -gnatdm
4367 elsif GNATprove_Mode
4368 and then Full_Analysis
4369 and then not Inside_A_Generic
4370 and then Present (Spec_Id)
4372 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4373 and then Body_Has_SPARK_Mode_On
4374 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4375 and then not Body_Has_Contract
4376 and then not Debug_Flag_M
4378 Build_Body_To_Inline (N, Spec_Id);
4381 -- When generating code, inherited pre/postconditions are handled when
4382 -- expanding the corresponding contract.
4384 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4385 -- of the specification we have to install the private withed units.
4386 -- This holds for child units as well.
4388 if Is_Compilation_Unit (Body_Id)
4389 or else Nkind (Parent (N)) = N_Compilation_Unit
4391 Install_Private_With_Clauses (Body_Id);
4394 Check_Anonymous_Return;
4396 -- Set the Protected_Formal field of each extra formal of the protected
4397 -- subprogram to reference the corresponding extra formal of the
4398 -- subprogram that implements it. For regular formals this occurs when
4399 -- the protected subprogram's declaration is expanded, but the extra
4400 -- formals don't get created until the subprogram is frozen. We need to
4401 -- do this before analyzing the protected subprogram's body so that any
4402 -- references to the original subprogram's extra formals will be changed
4403 -- refer to the implementing subprogram's formals (see Expand_Formal).
4405 if Present (Spec_Id)
4406 and then Is_Protected_Type (Scope (Spec_Id))
4407 and then Present (Protected_Body_Subprogram (Spec_Id))
4410 Impl_Subp : constant Entity_Id :=
4411 Protected_Body_Subprogram (Spec_Id);
4412 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4413 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4416 while Present (Prot_Ext_Formal) loop
4417 pragma Assert (Present (Impl_Ext_Formal));
4418 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4419 Next_Formal_With_Extras (Prot_Ext_Formal);
4420 Next_Formal_With_Extras (Impl_Ext_Formal);
4425 -- Generate minimum accessibility local objects to correspond with
4426 -- any extra formal added for anonymous access types. This new local
4427 -- object can then be used instead of the formal in case it is used
4428 -- in an actual to a call to a nested subprogram.
4430 -- This method is used to supplement our "small integer model" for
4431 -- accessibility-check generation (for more information see
4432 -- Dynamic_Accessibility_Level).
4434 -- Because we allow accessibility values greater than our expected value
4435 -- passing along the same extra accessibility formal as an actual
4436 -- to a nested subprogram becomes a problem because high values mean
4437 -- different things to the callee even though they are the same to the
4438 -- caller. So, as described in the first section, we create a local
4439 -- object representing the minimum of the accessibility level value that
4440 -- is passed in and the accessibility level of the callee's parameter
4441 -- and locals and use it in the case of a call to a nested subprogram.
4442 -- This generated object is refered to as a "minimum accessiblity
4445 if Present (Spec_Id) or else Present (Body_Id) then
4446 Body_Nod := Unit_Declaration_Node (Body_Id);
4451 -- Grab the appropriate formal depending on whether there exists
4452 -- an actual spec for the subprogram or whether we are dealing
4453 -- with a protected subprogram.
4455 if Present (Spec_Id) then
4456 if Present (Protected_Body_Subprogram (Spec_Id)) then
4457 Form := First_Formal (Protected_Body_Subprogram (Spec_Id));
4459 Form := First_Formal (Spec_Id);
4462 Form := First_Formal (Body_Id);
4465 -- Loop through formals if the subprogram is capable of accepting
4466 -- a generated local object. If it is not then it is also not
4467 -- capable of having local subprograms meaning it would not need
4468 -- a minimum accessibility level object anyway.
4470 if Present (Body_Nod)
4471 and then Has_Declarations (Body_Nod)
4472 and then Nkind (Body_Nod) /= N_Package_Specification
4474 while Present (Form) loop
4476 if Present (Extra_Accessibility (Form))
4477 and then No (Minimum_Accessibility (Form))
4479 -- Generate the minimum accessibility level object
4481 -- A60b : integer := integer'min(2, paramL);
4484 Loc : constant Source_Ptr := Sloc (Body_Nod);
4485 Obj_Node : constant Node_Id :=
4486 Make_Object_Declaration (Loc,
4487 Defining_Identifier =>
4489 (Loc, 'A', Extra_Accessibility (Form)),
4490 Object_Definition => New_Occurrence_Of
4491 (Standard_Integer, Loc),
4493 Make_Attribute_Reference (Loc,
4494 Prefix => New_Occurrence_Of
4495 (Standard_Integer, Loc),
4496 Attribute_Name => Name_Min,
4497 Expressions => New_List (
4498 Make_Integer_Literal (Loc,
4499 Object_Access_Level (Form)),
4501 (Extra_Accessibility (Form), Loc))));
4503 -- Add the new local object to the Minimum_Acc_Obj to
4504 -- be later prepended to the subprogram's list of
4505 -- declarations after we are sure all expansion is
4508 if Present (Minimum_Acc_Objs) then
4509 Prepend (Obj_Node, Minimum_Acc_Objs);
4511 Minimum_Acc_Objs := New_List (Obj_Node);
4514 -- Register the object and analyze it
4516 Set_Minimum_Accessibility
4517 (Form, Defining_Identifier (Obj_Node));
4529 -- Now we can go on to analyze the body
4531 HSS := Handled_Statement_Sequence (N);
4532 Set_Actual_Subtypes (N, Current_Scope);
4534 -- Add a declaration for the Protection object, renaming declarations
4535 -- for discriminals and privals and finally a declaration for the entry
4536 -- family index (if applicable). This form of early expansion is done
4537 -- when the Expander is active because Install_Private_Data_Declarations
4538 -- references entities which were created during regular expansion. The
4539 -- subprogram entity must come from source, and not be an internally
4540 -- generated subprogram.
4543 and then Present (Prot_Typ)
4544 and then Present (Spec_Id)
4545 and then Comes_From_Source (Spec_Id)
4546 and then not Is_Eliminated (Spec_Id)
4548 Install_Private_Data_Declarations
4549 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4552 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4553 -- may now appear in parameter and result profiles. Since the analysis
4554 -- of a subprogram body may use the parameter and result profile of the
4555 -- spec, swap any limited views with their non-limited counterpart.
4557 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4558 Exch_Views := Exchange_Limited_Views (Spec_Id);
4561 -- If the return type is an anonymous access type whose designated type
4562 -- is the limited view of a class-wide type and the non-limited view is
4563 -- available, update the return type accordingly.
4565 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4571 Rtyp := Etype (Spec_Id);
4573 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4574 Etyp := Directly_Designated_Type (Rtyp);
4576 if Is_Class_Wide_Type (Etyp)
4577 and then From_Limited_With (Etyp)
4580 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4586 -- Analyze any aspect specifications that appear on the subprogram body
4588 if Has_Aspects (N) then
4589 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4592 Analyze_Declarations (Declarations (N));
4594 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4596 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4597 if Present (SPARK_Pragma (Spec_Id)) then
4598 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4600 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4602 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4603 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4604 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4606 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4609 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4612 -- SPARK_Mode Off could complete no SPARK_Mode in a generic, either
4613 -- as specified in source code, or because SPARK_Mode On is ignored
4614 -- in an instance where the context is SPARK_Mode Off/Auto.
4616 elsif Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = Off
4617 and then (Is_Generic_Unit (Spec_Id) or else In_Instance)
4622 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4623 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4624 Error_Msg_Sloc := Sloc (Spec_Id);
4626 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4630 -- A subprogram body freezes its own contract. Analyze the contract
4631 -- after the declarations of the body have been processed as pragmas
4632 -- are now chained on the contract of the subprogram body.
4634 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4636 -- Check completion, and analyze the statements
4639 Inspect_Deferred_Constant_Completion (Declarations (N));
4642 -- Add the generated minimum accessibility objects to the subprogram
4643 -- body's list of declarations after analysis of the statements and
4646 while Is_Non_Empty_List (Minimum_Acc_Objs) loop
4647 if Present (Declarations (Body_Nod)) then
4648 Prepend (Remove_Head (Minimum_Acc_Objs), Declarations (Body_Nod));
4651 (Body_Nod, New_List (Remove_Head (Minimum_Acc_Objs)));
4655 -- Deal with end of scope processing for the body
4657 Process_End_Label (HSS, 't', Current_Scope);
4658 Update_Use_Clause_Chain;
4661 -- If we are compiling an entry wrapper, remove the enclosing
4662 -- synchronized object from the stack.
4664 if Is_Entry_Wrapper (Body_Id) then
4668 Check_Subprogram_Order (N);
4669 Set_Analyzed (Body_Id);
4671 -- If we have a separate spec, then the analysis of the declarations
4672 -- caused the entities in the body to be chained to the spec id, but
4673 -- we want them chained to the body id. Only the formal parameters
4674 -- end up chained to the spec id in this case.
4676 if Present (Spec_Id) then
4678 -- We must conform to the categorization of our spec
4680 Validate_Categorization_Dependency (N, Spec_Id);
4682 -- And if this is a child unit, the parent units must conform
4684 if Is_Child_Unit (Spec_Id) then
4685 Validate_Categorization_Dependency
4686 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4689 -- Here is where we move entities from the spec to the body
4691 -- Case where there are entities that stay with the spec
4693 if Present (Last_Real_Spec_Entity) then
4695 -- No body entities (happens when the only real spec entities come
4696 -- from precondition and postcondition pragmas).
4698 if No (Last_Entity (Body_Id)) then
4699 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4701 -- Body entities present (formals), so chain stuff past them
4705 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4708 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4709 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4710 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4712 -- Case where there are no spec entities, in this case there can be
4713 -- no body entities either, so just move everything.
4715 -- If the body is generated for an expression function, it may have
4716 -- been preanalyzed already, if 'access was applied to it.
4719 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4720 N_Expression_Function
4722 pragma Assert (No (Last_Entity (Body_Id)));
4726 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4727 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4728 Set_First_Entity (Spec_Id, Empty);
4729 Set_Last_Entity (Spec_Id, Empty);
4732 -- Otherwise the body does not complete a previous declaration. Check
4733 -- the categorization of the body against the units it withs.
4736 Validate_Categorization_Dependency (N, Body_Id);
4739 Check_Missing_Return;
4741 -- Now we are going to check for variables that are never modified in
4742 -- the body of the procedure. But first we deal with a special case
4743 -- where we want to modify this check. If the body of the subprogram
4744 -- starts with a raise statement or its equivalent, or if the body
4745 -- consists entirely of a null statement, then it is pretty obvious that
4746 -- it is OK to not reference the parameters. For example, this might be
4747 -- the following common idiom for a stubbed function: statement of the
4748 -- procedure raises an exception. In particular this deals with the
4749 -- common idiom of a stubbed function, which appears something like:
4751 -- function F (A : Integer) return Some_Type;
4754 -- raise Program_Error;
4758 -- Here the purpose of X is simply to satisfy the annoying requirement
4759 -- in Ada that there be at least one return, and we certainly do not
4760 -- want to go posting warnings on X that it is not initialized. On
4761 -- the other hand, if X is entirely unreferenced that should still
4764 -- What we do is to detect these cases, and if we find them, flag the
4765 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4766 -- suppress unwanted warnings. For the case of the function stub above
4767 -- we have a special test to set X as apparently assigned to suppress
4774 -- Skip call markers installed by the ABE mechanism, labels, and
4775 -- Push_xxx_Error_Label to find the first real statement.
4777 Stm := First (Statements (HSS));
4778 while Nkind_In (Stm, N_Call_Marker, N_Label)
4779 or else Nkind (Stm) in N_Push_xxx_Label
4784 -- Do the test on the original statement before expansion
4787 Ostm : constant Node_Id := Original_Node (Stm);
4790 -- If explicit raise statement, turn on flag
4792 if Nkind (Ostm) = N_Raise_Statement then
4793 Set_Trivial_Subprogram (Stm);
4795 -- If null statement, and no following statements, turn on flag
4797 elsif Nkind (Stm) = N_Null_Statement
4798 and then Comes_From_Source (Stm)
4799 and then No (Next (Stm))
4801 Set_Trivial_Subprogram (Stm);
4803 -- Check for explicit call cases which likely raise an exception
4805 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4806 if Is_Entity_Name (Name (Ostm)) then
4808 Ent : constant Entity_Id := Entity (Name (Ostm));
4811 -- If the procedure is marked No_Return, then likely it
4812 -- raises an exception, but in any case it is not coming
4813 -- back here, so turn on the flag.
4816 and then Ekind (Ent) = E_Procedure
4817 and then No_Return (Ent)
4819 Set_Trivial_Subprogram (Stm);
4827 -- Check for variables that are never modified
4834 -- If there is a separate spec, then transfer Never_Set_In_Source
4835 -- flags from out parameters to the corresponding entities in the
4836 -- body. The reason we do that is we want to post error flags on
4837 -- the body entities, not the spec entities.
4839 if Present (Spec_Id) then
4840 E1 := First_Entity (Spec_Id);
4841 while Present (E1) loop
4842 if Ekind (E1) = E_Out_Parameter then
4843 E2 := First_Entity (Body_Id);
4844 while Present (E2) loop
4845 exit when Chars (E1) = Chars (E2);
4849 if Present (E2) then
4850 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4858 -- Check references of the subprogram spec when we are dealing with
4859 -- an expression function due to it having a generated body.
4860 -- Otherwise, we simply check the formals of the subprogram body.
4862 if Present (Spec_Id)
4863 and then Is_Expression_Function (Spec_Id)
4865 Check_References (Spec_Id);
4867 Check_References (Body_Id);
4871 -- Check for nested subprogram, and mark outer level subprogram if so
4877 if Present (Spec_Id) then
4884 Ent := Enclosing_Subprogram (Ent);
4885 exit when No (Ent) or else Is_Subprogram (Ent);
4888 if Present (Ent) then
4889 Set_Has_Nested_Subprogram (Ent);
4893 -- Restore the limited views in the spec, if any, to let the back end
4894 -- process it without running into circularities.
4896 if Exch_Views /= No_Elist then
4897 Restore_Limited_Views (Exch_Views);
4900 if Mask_Types /= No_Elist then
4901 Unmask_Unfrozen_Types (Mask_Types);
4904 if Present (Desig_View) then
4905 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4909 if Present (Ignored_Ghost_Region) then
4910 Expander_Active := Saved_EA;
4913 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4914 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4915 end Analyze_Subprogram_Body_Helper;
4917 ------------------------------------
4918 -- Analyze_Subprogram_Declaration --
4919 ------------------------------------
4921 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4922 Scop : constant Entity_Id := Current_Scope;
4923 Designator : Entity_Id;
4925 Is_Completion : Boolean;
4926 -- Indicates whether a null procedure declaration is a completion
4929 -- Null procedures are not allowed in SPARK
4931 if Nkind (Specification (N)) = N_Procedure_Specification
4932 and then Null_Present (Specification (N))
4934 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4936 -- Null procedures are allowed in protected types, following the
4937 -- recent AI12-0147.
4939 if Is_Protected_Type (Current_Scope)
4940 and then Ada_Version < Ada_2012
4942 Error_Msg_N ("protected operation cannot be a null procedure", N);
4945 Analyze_Null_Procedure (N, Is_Completion);
4947 -- The null procedure acts as a body, nothing further is needed
4949 if Is_Completion then
4954 Designator := Analyze_Subprogram_Specification (Specification (N));
4956 -- A reference may already have been generated for the unit name, in
4957 -- which case the following call is redundant. However it is needed for
4958 -- declarations that are the rewriting of an expression function.
4960 Generate_Definition (Designator);
4962 -- Set the SPARK mode from the current context (may be overwritten later
4963 -- with explicit pragma). This is not done for entry barrier functions
4964 -- because they are generated outside the protected type and should not
4965 -- carry the mode of the enclosing context.
4967 if Nkind (N) = N_Subprogram_Declaration
4968 and then Is_Entry_Barrier_Function (N)
4973 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4974 Set_SPARK_Pragma_Inherited (Designator);
4977 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4978 -- the body of this subprogram is instantiated or inlined later and out
4979 -- of context. The body uses this attribute to restore the value of the
4982 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4983 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4986 -- Preserve relevant elaboration-related attributes of the context which
4987 -- are no longer available or very expensive to recompute once analysis,
4988 -- resolution, and expansion are over.
4990 Mark_Elaboration_Attributes
4991 (N_Id => Designator,
4995 if Debug_Flag_C then
4996 Write_Str ("==> subprogram spec ");
4997 Write_Name (Chars (Designator));
4998 Write_Str (" from ");
4999 Write_Location (Sloc (N));
5004 Validate_RCI_Subprogram_Declaration (N);
5005 New_Overloaded_Entity (Designator);
5006 Check_Delayed_Subprogram (Designator);
5008 -- If the type of the first formal of the current subprogram is a non-
5009 -- generic tagged private type, mark the subprogram as being a private
5010 -- primitive. Ditto if this is a function with controlling result, and
5011 -- the return type is currently private. In both cases, the type of the
5012 -- controlling argument or result must be in the current scope for the
5013 -- operation to be primitive.
5015 if Has_Controlling_Result (Designator)
5016 and then Is_Private_Type (Etype (Designator))
5017 and then Scope (Etype (Designator)) = Current_Scope
5018 and then not Is_Generic_Actual_Type (Etype (Designator))
5020 Set_Is_Private_Primitive (Designator);
5022 elsif Present (First_Formal (Designator)) then
5024 Formal_Typ : constant Entity_Id :=
5025 Etype (First_Formal (Designator));
5027 Set_Is_Private_Primitive (Designator,
5028 Is_Tagged_Type (Formal_Typ)
5029 and then Scope (Formal_Typ) = Current_Scope
5030 and then Is_Private_Type (Formal_Typ)
5031 and then not Is_Generic_Actual_Type (Formal_Typ));
5035 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
5038 if Ada_Version >= Ada_2005
5039 and then Comes_From_Source (N)
5040 and then Is_Dispatching_Operation (Designator)
5047 if Has_Controlling_Result (Designator) then
5048 Etyp := Etype (Designator);
5051 E := First_Entity (Designator);
5053 and then Is_Formal (E)
5054 and then not Is_Controlling_Formal (E)
5062 if Is_Access_Type (Etyp) then
5063 Etyp := Directly_Designated_Type (Etyp);
5066 if Is_Interface (Etyp)
5067 and then not Is_Abstract_Subprogram (Designator)
5068 and then not (Ekind (Designator) = E_Procedure
5069 and then Null_Present (Specification (N)))
5071 Error_Msg_Name_1 := Chars (Defining_Entity (N));
5073 -- Specialize error message based on procedures vs. functions,
5074 -- since functions can't be null subprograms.
5076 if Ekind (Designator) = E_Procedure then
5078 ("interface procedure % must be abstract or null", N);
5081 ("interface function % must be abstract", N);
5087 -- What is the following code for, it used to be
5089 -- ??? Set_Suppress_Elaboration_Checks
5090 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
5092 -- The following seems equivalent, but a bit dubious
5094 if Elaboration_Checks_Suppressed (Designator) then
5095 Set_Kill_Elaboration_Checks (Designator);
5098 -- For a compilation unit, set body required. This flag will only be
5099 -- reset if a valid Import or Interface pragma is processed later on.
5101 if Nkind (Parent (N)) = N_Compilation_Unit then
5102 Set_Body_Required (Parent (N), True);
5104 if Ada_Version >= Ada_2005
5105 and then Nkind (Specification (N)) = N_Procedure_Specification
5106 and then Null_Present (Specification (N))
5109 ("null procedure cannot be declared at library level", N);
5113 Generate_Reference_To_Formals (Designator);
5114 Check_Eliminated (Designator);
5116 if Debug_Flag_C then
5118 Write_Str ("<== subprogram spec ");
5119 Write_Name (Chars (Designator));
5120 Write_Str (" from ");
5121 Write_Location (Sloc (N));
5125 -- Indicate that this is a protected operation, because it may be used
5126 -- in subsequent declarations within the protected type.
5128 if Is_Protected_Type (Current_Scope) then
5129 Set_Convention (Designator, Convention_Protected);
5132 List_Inherited_Pre_Post_Aspects (Designator);
5134 -- Process the aspects before establishing the proper categorization in
5135 -- case the subprogram is a compilation unit and one of its aspects is
5136 -- converted into a categorization pragma.
5138 if Has_Aspects (N) then
5139 Analyze_Aspect_Specifications (N, Designator);
5142 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
5143 Set_Categorization_From_Scope (Designator, Scop);
5145 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
5146 -- proper categorization of the unit based on its pragmas.
5149 Push_Scope (Designator);
5150 Set_Categorization_From_Pragmas (N);
5151 Validate_Categorization_Dependency (N, Designator);
5154 end Analyze_Subprogram_Declaration;
5156 --------------------------------------
5157 -- Analyze_Subprogram_Specification --
5158 --------------------------------------
5160 -- Reminder: N here really is a subprogram specification (not a subprogram
5161 -- declaration). This procedure is called to analyze the specification in
5162 -- both subprogram bodies and subprogram declarations (specs).
5164 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
5165 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
5166 -- Determine whether entity E denotes the spec or body of an invariant
5169 ------------------------------------
5170 -- Is_Invariant_Procedure_Or_Body --
5171 ------------------------------------
5173 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
5174 Decl : constant Node_Id := Unit_Declaration_Node (E);
5178 if Nkind (Decl) = N_Subprogram_Body then
5179 Spec := Corresponding_Spec (Decl);
5186 and then Ekind (Spec) = E_Procedure
5187 and then (Is_Partial_Invariant_Procedure (Spec)
5188 or else Is_Invariant_Procedure (Spec));
5189 end Is_Invariant_Procedure_Or_Body;
5193 Designator : constant Entity_Id := Defining_Entity (N);
5194 Formals : constant List_Id := Parameter_Specifications (N);
5196 -- Start of processing for Analyze_Subprogram_Specification
5199 -- User-defined operator is not allowed in SPARK, except as a renaming
5201 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
5202 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
5204 Check_SPARK_05_Restriction
5205 ("user-defined operator is not allowed", N);
5208 -- Proceed with analysis. Do not emit a cross-reference entry if the
5209 -- specification comes from an expression function, because it may be
5210 -- the completion of a previous declaration. If it is not, the cross-
5211 -- reference entry will be emitted for the new subprogram declaration.
5213 if Nkind (Parent (N)) /= N_Expression_Function then
5214 Generate_Definition (Designator);
5217 if Nkind (N) = N_Function_Specification then
5218 Set_Ekind (Designator, E_Function);
5219 Set_Mechanism (Designator, Default_Mechanism);
5221 Set_Ekind (Designator, E_Procedure);
5222 Set_Etype (Designator, Standard_Void_Type);
5225 -- Flag Is_Inlined_Always is True by default, and reversed to False for
5226 -- those subprograms which could be inlined in GNATprove mode (because
5227 -- Body_To_Inline is non-Empty) but should not be inlined.
5229 if GNATprove_Mode then
5230 Set_Is_Inlined_Always (Designator);
5233 -- Introduce new scope for analysis of the formals and the return type
5235 Set_Scope (Designator, Current_Scope);
5237 if Present (Formals) then
5238 Push_Scope (Designator);
5239 Process_Formals (Formals, N);
5241 -- Check dimensions in N for formals with default expression
5243 Analyze_Dimension_Formals (N, Formals);
5245 -- Ada 2005 (AI-345): If this is an overriding operation of an
5246 -- inherited interface operation, and the controlling type is
5247 -- a synchronized type, replace the type with its corresponding
5248 -- record, to match the proper signature of an overriding operation.
5249 -- Same processing for an access parameter whose designated type is
5250 -- derived from a synchronized interface.
5252 -- This modification is not done for invariant procedures because
5253 -- the corresponding record may not necessarely be visible when the
5254 -- concurrent type acts as the full view of a private type.
5257 -- type Prot is private with Type_Invariant => ...;
5258 -- procedure ConcInvariant (Obj : Prot);
5260 -- protected type Prot is ...;
5261 -- type Concurrent_Record_Prot is record ...;
5262 -- procedure ConcInvariant (Obj : Prot) is
5264 -- end ConcInvariant;
5267 -- In the example above, both the spec and body of the invariant
5268 -- procedure must utilize the private type as the controlling type.
5270 if Ada_Version >= Ada_2005
5271 and then not Is_Invariant_Procedure_Or_Body (Designator)
5275 Formal_Typ : Entity_Id;
5276 Rec_Typ : Entity_Id;
5277 Desig_Typ : Entity_Id;
5280 Formal := First_Formal (Designator);
5281 while Present (Formal) loop
5282 Formal_Typ := Etype (Formal);
5284 if Is_Concurrent_Type (Formal_Typ)
5285 and then Present (Corresponding_Record_Type (Formal_Typ))
5287 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5289 if Present (Interfaces (Rec_Typ)) then
5290 Set_Etype (Formal, Rec_Typ);
5293 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5294 Desig_Typ := Designated_Type (Formal_Typ);
5296 if Is_Concurrent_Type (Desig_Typ)
5297 and then Present (Corresponding_Record_Type (Desig_Typ))
5299 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5301 if Present (Interfaces (Rec_Typ)) then
5302 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5307 Next_Formal (Formal);
5314 -- The subprogram scope is pushed and popped around the processing of
5315 -- the return type for consistency with call above to Process_Formals
5316 -- (which itself can call Analyze_Return_Type), and to ensure that any
5317 -- itype created for the return type will be associated with the proper
5320 elsif Nkind (N) = N_Function_Specification then
5321 Push_Scope (Designator);
5322 Analyze_Return_Type (N);
5328 if Nkind (N) = N_Function_Specification then
5330 -- Deal with operator symbol case
5332 if Nkind (Designator) = N_Defining_Operator_Symbol then
5333 Valid_Operator_Definition (Designator);
5336 May_Need_Actuals (Designator);
5338 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5339 -- the subprogram is abstract also. This does not apply to renaming
5340 -- declarations, where abstractness is inherited, and to subprogram
5341 -- bodies generated for stream operations, which become renamings as
5344 -- In case of primitives associated with abstract interface types
5345 -- the check is applied later (see Analyze_Subprogram_Declaration).
5347 if not Nkind_In (Original_Node (Parent (N)),
5348 N_Abstract_Subprogram_Declaration,
5349 N_Formal_Abstract_Subprogram_Declaration,
5350 N_Subprogram_Renaming_Declaration)
5352 if Is_Abstract_Type (Etype (Designator))
5353 and then not Is_Interface (Etype (Designator))
5356 ("function that returns abstract type must be abstract", N);
5358 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5359 -- access result whose designated type is abstract.
5361 elsif Ada_Version >= Ada_2012
5362 and then Nkind (Result_Definition (N)) = N_Access_Definition
5364 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5365 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5368 ("function whose access result designates abstract type "
5369 & "must be abstract", N);
5375 end Analyze_Subprogram_Specification;
5377 -----------------------
5378 -- Check_Conformance --
5379 -----------------------
5381 procedure Check_Conformance
5382 (New_Id : Entity_Id;
5384 Ctype : Conformance_Type;
5386 Conforms : out Boolean;
5387 Err_Loc : Node_Id := Empty;
5388 Get_Inst : Boolean := False;
5389 Skip_Controlling_Formals : Boolean := False)
5391 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5392 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5393 -- If Errmsg is True, then processing continues to post an error message
5394 -- for conformance error on given node. Two messages are output. The
5395 -- first message points to the previous declaration with a general "no
5396 -- conformance" message. The second is the detailed reason, supplied as
5397 -- Msg. The parameter N provide information for a possible & insertion
5398 -- in the message, and also provides the location for posting the
5399 -- message in the absence of a specified Err_Loc location.
5401 function Conventions_Match
5403 Id2 : Entity_Id) return Boolean;
5404 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5407 -----------------------
5408 -- Conformance_Error --
5409 -----------------------
5411 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5418 if No (Err_Loc) then
5424 Error_Msg_Sloc := Sloc (Old_Id);
5427 when Type_Conformant =>
5428 Error_Msg_N -- CODEFIX
5429 ("not type conformant with declaration#!", Enode);
5431 when Mode_Conformant =>
5432 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5434 ("not mode conformant with operation inherited#!",
5438 ("not mode conformant with declaration#!", Enode);
5441 when Subtype_Conformant =>
5442 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5444 ("not subtype conformant with operation inherited#!",
5448 ("not subtype conformant with declaration#!", Enode);
5451 when Fully_Conformant =>
5452 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5453 Error_Msg_N -- CODEFIX
5454 ("not fully conformant with operation inherited#!",
5457 Error_Msg_N -- CODEFIX
5458 ("not fully conformant with declaration#!", Enode);
5462 Error_Msg_NE (Msg, Enode, N);
5464 end Conformance_Error;
5466 -----------------------
5467 -- Conventions_Match --
5468 -----------------------
5470 function Conventions_Match
5472 Id2 : Entity_Id) return Boolean
5475 -- Ignore the conventions of anonymous access-to-subprogram types
5476 -- and subprogram types because these are internally generated and
5477 -- the only way these may receive a convention is if they inherit
5478 -- the convention of a related subprogram.
5480 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5483 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5488 -- Otherwise compare the conventions directly
5491 return Convention (Id1) = Convention (Id2);
5493 end Conventions_Match;
5497 Old_Type : constant Entity_Id := Etype (Old_Id);
5498 New_Type : constant Entity_Id := Etype (New_Id);
5499 Old_Formal : Entity_Id;
5500 New_Formal : Entity_Id;
5501 Access_Types_Match : Boolean;
5502 Old_Formal_Base : Entity_Id;
5503 New_Formal_Base : Entity_Id;
5505 -- Start of processing for Check_Conformance
5510 -- We need a special case for operators, since they don't appear
5513 if Ctype = Type_Conformant then
5514 if Ekind (New_Id) = E_Operator
5515 and then Operator_Matches_Spec (New_Id, Old_Id)
5521 -- If both are functions/operators, check return types conform
5523 if Old_Type /= Standard_Void_Type
5525 New_Type /= Standard_Void_Type
5527 -- If we are checking interface conformance we omit controlling
5528 -- arguments and result, because we are only checking the conformance
5529 -- of the remaining parameters.
5531 if Has_Controlling_Result (Old_Id)
5532 and then Has_Controlling_Result (New_Id)
5533 and then Skip_Controlling_Formals
5537 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5538 if Ctype >= Subtype_Conformant
5539 and then not Predicates_Match (Old_Type, New_Type)
5542 ("\predicate of return type does not match!", New_Id);
5545 ("\return type does not match!", New_Id);
5551 -- Ada 2005 (AI-231): In case of anonymous access types check the
5552 -- null-exclusion and access-to-constant attributes match.
5554 if Ada_Version >= Ada_2005
5555 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5557 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5558 or else Is_Access_Constant (Etype (Old_Type)) /=
5559 Is_Access_Constant (Etype (New_Type)))
5561 Conformance_Error ("\return type does not match!", New_Id);
5565 -- If either is a function/operator and the other isn't, error
5567 elsif Old_Type /= Standard_Void_Type
5568 or else New_Type /= Standard_Void_Type
5570 Conformance_Error ("\functions can only match functions!", New_Id);
5574 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5575 -- If this is a renaming as body, refine error message to indicate that
5576 -- the conflict is with the original declaration. If the entity is not
5577 -- frozen, the conventions don't have to match, the one of the renamed
5578 -- entity is inherited.
5580 if Ctype >= Subtype_Conformant then
5581 if not Conventions_Match (Old_Id, New_Id) then
5582 if not Is_Frozen (New_Id) then
5585 elsif Present (Err_Loc)
5586 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5587 and then Present (Corresponding_Spec (Err_Loc))
5589 Error_Msg_Name_1 := Chars (New_Id);
5591 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5592 Conformance_Error ("\prior declaration for% has convention %!");
5595 Conformance_Error ("\calling conventions do not match!");
5600 elsif Is_Formal_Subprogram (Old_Id)
5601 or else Is_Formal_Subprogram (New_Id)
5602 or else (Is_Subprogram (New_Id)
5603 and then Present (Alias (New_Id))
5604 and then Is_Formal_Subprogram (Alias (New_Id)))
5607 ("\formal subprograms are not subtype conformant "
5608 & "(RM 6.3.1 (17/3))");
5612 -- Deal with parameters
5614 -- Note: we use the entity information, rather than going directly
5615 -- to the specification in the tree. This is not only simpler, but
5616 -- absolutely necessary for some cases of conformance tests between
5617 -- operators, where the declaration tree simply does not exist.
5619 Old_Formal := First_Formal (Old_Id);
5620 New_Formal := First_Formal (New_Id);
5621 while Present (Old_Formal) and then Present (New_Formal) loop
5622 if Is_Controlling_Formal (Old_Formal)
5623 and then Is_Controlling_Formal (New_Formal)
5624 and then Skip_Controlling_Formals
5626 -- The controlling formals will have different types when
5627 -- comparing an interface operation with its match, but both
5628 -- or neither must be access parameters.
5630 if Is_Access_Type (Etype (Old_Formal))
5632 Is_Access_Type (Etype (New_Formal))
5634 goto Skip_Controlling_Formal;
5637 ("\access parameter does not match!", New_Formal);
5641 -- Ada 2012: Mode conformance also requires that formal parameters
5642 -- be both aliased, or neither.
5644 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5645 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5647 ("\aliased parameter mismatch!", New_Formal);
5651 if Ctype = Fully_Conformant then
5653 -- Names must match. Error message is more accurate if we do
5654 -- this before checking that the types of the formals match.
5656 if Chars (Old_Formal) /= Chars (New_Formal) then
5657 Conformance_Error ("\name& does not match!", New_Formal);
5659 -- Set error posted flag on new formal as well to stop
5660 -- junk cascaded messages in some cases.
5662 Set_Error_Posted (New_Formal);
5666 -- Null exclusion must match
5668 if Null_Exclusion_Present (Parent (Old_Formal))
5670 Null_Exclusion_Present (Parent (New_Formal))
5672 -- Only give error if both come from source. This should be
5673 -- investigated some time, since it should not be needed ???
5675 if Comes_From_Source (Old_Formal)
5677 Comes_From_Source (New_Formal)
5680 ("\null exclusion for& does not match", New_Formal);
5682 -- Mark error posted on the new formal to avoid duplicated
5683 -- complaint about types not matching.
5685 Set_Error_Posted (New_Formal);
5690 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5691 -- case occurs whenever a subprogram is being renamed and one of its
5692 -- parameters imposes a null exclusion. For example:
5694 -- type T is null record;
5695 -- type Acc_T is access T;
5696 -- subtype Acc_T_Sub is Acc_T;
5698 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5699 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5702 Old_Formal_Base := Etype (Old_Formal);
5703 New_Formal_Base := Etype (New_Formal);
5706 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5707 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5710 Access_Types_Match := Ada_Version >= Ada_2005
5712 -- Ensure that this rule is only applied when New_Id is a
5713 -- renaming of Old_Id.
5715 and then Nkind (Parent (Parent (New_Id))) =
5716 N_Subprogram_Renaming_Declaration
5717 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5718 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5719 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5721 -- Now handle the allowed access-type case
5723 and then Is_Access_Type (Old_Formal_Base)
5724 and then Is_Access_Type (New_Formal_Base)
5726 -- The type kinds must match. The only exception occurs with
5727 -- multiple generics of the form:
5730 -- type F is private; type A is private;
5731 -- type F_Ptr is access F; type A_Ptr is access A;
5732 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5733 -- package F_Pack is ... package A_Pack is
5734 -- package F_Inst is
5735 -- new F_Pack (A, A_Ptr, A_P);
5737 -- When checking for conformance between the parameters of A_P
5738 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5739 -- because the compiler has transformed A_Ptr into a subtype of
5740 -- F_Ptr. We catch this case in the code below.
5742 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5744 (Is_Generic_Type (Old_Formal_Base)
5745 and then Is_Generic_Type (New_Formal_Base)
5746 and then Is_Internal (New_Formal_Base)
5747 and then Etype (Etype (New_Formal_Base)) =
5749 and then Directly_Designated_Type (Old_Formal_Base) =
5750 Directly_Designated_Type (New_Formal_Base)
5751 and then ((Is_Itype (Old_Formal_Base)
5752 and then (Can_Never_Be_Null (Old_Formal_Base)
5753 or else Is_Access_Constant
5756 (Is_Itype (New_Formal_Base)
5757 and then (Can_Never_Be_Null (New_Formal_Base)
5758 or else Is_Access_Constant
5759 (New_Formal_Base))));
5761 -- Types must always match. In the visible part of an instance,
5762 -- usual overloading rules for dispatching operations apply, and
5763 -- we check base types (not the actual subtypes).
5765 if In_Instance_Visible_Part
5766 and then Is_Dispatching_Operation (New_Id)
5768 if not Conforming_Types
5769 (T1 => Base_Type (Etype (Old_Formal)),
5770 T2 => Base_Type (Etype (New_Formal)),
5772 Get_Inst => Get_Inst)
5773 and then not Access_Types_Match
5775 Conformance_Error ("\type of & does not match!", New_Formal);
5779 elsif not Conforming_Types
5780 (T1 => Old_Formal_Base,
5781 T2 => New_Formal_Base,
5783 Get_Inst => Get_Inst)
5784 and then not Access_Types_Match
5786 -- Don't give error message if old type is Any_Type. This test
5787 -- avoids some cascaded errors, e.g. in case of a bad spec.
5789 if Errmsg and then Old_Formal_Base = Any_Type then
5792 if Ctype >= Subtype_Conformant
5794 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5797 ("\predicate of & does not match!", New_Formal);
5800 ("\type of & does not match!", New_Formal);
5802 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5804 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5812 -- For mode conformance, mode must match
5814 if Ctype >= Mode_Conformant then
5815 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5816 if not Ekind_In (New_Id, E_Function, E_Procedure)
5817 or else not Is_Primitive_Wrapper (New_Id)
5819 Conformance_Error ("\mode of & does not match!", New_Formal);
5823 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5825 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5827 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5830 ("\mode of & does not match!", New_Formal);
5837 -- Part of mode conformance for access types is having the same
5838 -- constant modifier.
5840 elsif Access_Types_Match
5841 and then Is_Access_Constant (Old_Formal_Base) /=
5842 Is_Access_Constant (New_Formal_Base)
5845 ("\constant modifier does not match!", New_Formal);
5850 if Ctype >= Subtype_Conformant then
5852 -- Ada 2005 (AI-231): In case of anonymous access types check
5853 -- the null-exclusion and access-to-constant attributes must
5854 -- match. For null exclusion, we test the types rather than the
5855 -- formals themselves, since the attribute is only set reliably
5856 -- on the formals in the Ada 95 case, and we exclude the case
5857 -- where Old_Formal is marked as controlling, to avoid errors
5858 -- when matching completing bodies with dispatching declarations
5859 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5861 if Ada_Version >= Ada_2005
5862 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5863 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5865 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5866 Can_Never_Be_Null (Etype (New_Formal))
5868 not Is_Controlling_Formal (Old_Formal))
5870 Is_Access_Constant (Etype (Old_Formal)) /=
5871 Is_Access_Constant (Etype (New_Formal)))
5873 -- Do not complain if error already posted on New_Formal. This
5874 -- avoids some redundant error messages.
5876 and then not Error_Posted (New_Formal)
5878 -- It is allowed to omit the null-exclusion in case of stream
5879 -- attribute subprograms. We recognize stream subprograms
5880 -- through their TSS-generated suffix.
5883 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5886 if TSS_Name /= TSS_Stream_Read
5887 and then TSS_Name /= TSS_Stream_Write
5888 and then TSS_Name /= TSS_Stream_Input
5889 and then TSS_Name /= TSS_Stream_Output
5891 -- Here we have a definite conformance error. It is worth
5892 -- special casing the error message for the case of a
5893 -- controlling formal (which excludes null).
5895 if Is_Controlling_Formal (New_Formal) then
5896 Error_Msg_Node_2 := Scope (New_Formal);
5898 ("\controlling formal & of & excludes null, "
5899 & "declaration must exclude null as well",
5902 -- Normal case (couldn't we give more detail here???)
5906 ("\type of & does not match!", New_Formal);
5915 -- Full conformance checks
5917 if Ctype = Fully_Conformant then
5919 -- We have checked already that names match
5921 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5923 -- Check default expressions for in parameters
5926 NewD : constant Boolean :=
5927 Present (Default_Value (New_Formal));
5928 OldD : constant Boolean :=
5929 Present (Default_Value (Old_Formal));
5931 if NewD or OldD then
5933 -- The old default value has been analyzed because the
5934 -- current full declaration will have frozen everything
5935 -- before. The new default value has not been analyzed,
5936 -- so analyze it now before we check for conformance.
5939 Push_Scope (New_Id);
5940 Preanalyze_Spec_Expression
5941 (Default_Value (New_Formal), Etype (New_Formal));
5945 if not (NewD and OldD)
5946 or else not Fully_Conformant_Expressions
5947 (Default_Value (Old_Formal),
5948 Default_Value (New_Formal))
5951 ("\default expression for & does not match!",
5960 -- A couple of special checks for Ada 83 mode. These checks are
5961 -- skipped if either entity is an operator in package Standard,
5962 -- or if either old or new instance is not from the source program.
5964 if Ada_Version = Ada_83
5965 and then Sloc (Old_Id) > Standard_Location
5966 and then Sloc (New_Id) > Standard_Location
5967 and then Comes_From_Source (Old_Id)
5968 and then Comes_From_Source (New_Id)
5971 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5972 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5975 -- Explicit IN must be present or absent in both cases. This
5976 -- test is required only in the full conformance case.
5978 if In_Present (Old_Param) /= In_Present (New_Param)
5979 and then Ctype = Fully_Conformant
5982 ("\(Ada 83) IN must appear in both declarations",
5987 -- Grouping (use of comma in param lists) must be the same
5988 -- This is where we catch a misconformance like:
5991 -- A : Integer; B : Integer
5993 -- which are represented identically in the tree except
5994 -- for the setting of the flags More_Ids and Prev_Ids.
5996 if More_Ids (Old_Param) /= More_Ids (New_Param)
5997 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
6000 ("\grouping of & does not match!", New_Formal);
6006 -- This label is required when skipping controlling formals
6008 <<Skip_Controlling_Formal>>
6010 Next_Formal (Old_Formal);
6011 Next_Formal (New_Formal);
6014 if Present (Old_Formal) then
6015 Conformance_Error ("\too few parameters!");
6018 elsif Present (New_Formal) then
6019 Conformance_Error ("\too many parameters!", New_Formal);
6022 end Check_Conformance;
6024 -----------------------
6025 -- Check_Conventions --
6026 -----------------------
6028 procedure Check_Conventions (Typ : Entity_Id) is
6029 Ifaces_List : Elist_Id;
6031 procedure Check_Convention (Op : Entity_Id);
6032 -- Verify that the convention of inherited dispatching operation Op is
6033 -- consistent among all subprograms it overrides. In order to minimize
6034 -- the search, Search_From is utilized to designate a specific point in
6035 -- the list rather than iterating over the whole list once more.
6037 ----------------------
6038 -- Check_Convention --
6039 ----------------------
6041 procedure Check_Convention (Op : Entity_Id) is
6042 Op_Conv : constant Convention_Id := Convention (Op);
6043 Iface_Conv : Convention_Id;
6044 Iface_Elmt : Elmt_Id;
6045 Iface_Prim_Elmt : Elmt_Id;
6046 Iface_Prim : Entity_Id;
6049 Iface_Elmt := First_Elmt (Ifaces_List);
6050 while Present (Iface_Elmt) loop
6052 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
6053 while Present (Iface_Prim_Elmt) loop
6054 Iface_Prim := Node (Iface_Prim_Elmt);
6055 Iface_Conv := Convention (Iface_Prim);
6057 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
6058 and then Iface_Conv /= Op_Conv
6061 ("inconsistent conventions in primitive operations", Typ);
6063 Error_Msg_Name_1 := Chars (Op);
6064 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
6065 Error_Msg_Sloc := Sloc (Op);
6067 if Comes_From_Source (Op) or else No (Alias (Op)) then
6068 if not Present (Overridden_Operation (Op)) then
6069 Error_Msg_N ("\\primitive % defined #", Typ);
6072 ("\\overriding operation % with "
6073 & "convention % defined #", Typ);
6076 else pragma Assert (Present (Alias (Op)));
6077 Error_Msg_Sloc := Sloc (Alias (Op));
6078 Error_Msg_N ("\\inherited operation % with "
6079 & "convention % defined #", Typ);
6082 Error_Msg_Name_1 := Chars (Op);
6083 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
6084 Error_Msg_Sloc := Sloc (Iface_Prim);
6085 Error_Msg_N ("\\overridden operation % with "
6086 & "convention % defined #", Typ);
6088 -- Avoid cascading errors
6093 Next_Elmt (Iface_Prim_Elmt);
6096 Next_Elmt (Iface_Elmt);
6098 end Check_Convention;
6102 Prim_Op : Entity_Id;
6103 Prim_Op_Elmt : Elmt_Id;
6105 -- Start of processing for Check_Conventions
6108 if not Has_Interfaces (Typ) then
6112 Collect_Interfaces (Typ, Ifaces_List);
6114 -- The algorithm checks every overriding dispatching operation against
6115 -- all the corresponding overridden dispatching operations, detecting
6116 -- differences in conventions.
6118 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
6119 while Present (Prim_Op_Elmt) loop
6120 Prim_Op := Node (Prim_Op_Elmt);
6122 -- A small optimization: skip the predefined dispatching operations
6123 -- since they always have the same convention.
6125 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
6126 Check_Convention (Prim_Op);
6129 Next_Elmt (Prim_Op_Elmt);
6131 end Check_Conventions;
6133 ------------------------------
6134 -- Check_Delayed_Subprogram --
6135 ------------------------------
6137 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
6138 procedure Possible_Freeze (T : Entity_Id);
6139 -- T is the type of either a formal parameter or of the return type. If
6140 -- T is not yet frozen and needs a delayed freeze, then the subprogram
6141 -- itself must be delayed.
6143 ---------------------
6144 -- Possible_Freeze --
6145 ---------------------
6147 procedure Possible_Freeze (T : Entity_Id) is
6148 Scop : constant Entity_Id := Scope (Designator);
6151 -- If the subprogram appears within a package instance (which may be
6152 -- the wrapper package of a subprogram instance) the freeze node for
6153 -- that package will freeze the subprogram at the proper place, so
6154 -- do not emit a freeze node for the subprogram, given that it may
6155 -- appear in the wrong scope.
6157 if Ekind (Scop) = E_Package
6158 and then not Comes_From_Source (Scop)
6159 and then Is_Generic_Instance (Scop)
6163 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
6164 Set_Has_Delayed_Freeze (Designator);
6166 elsif Is_Access_Type (T)
6167 and then Has_Delayed_Freeze (Designated_Type (T))
6168 and then not Is_Frozen (Designated_Type (T))
6170 Set_Has_Delayed_Freeze (Designator);
6172 end Possible_Freeze;
6178 -- Start of processing for Check_Delayed_Subprogram
6181 -- All subprograms, including abstract subprograms, may need a freeze
6182 -- node if some formal type or the return type needs one.
6184 Possible_Freeze (Etype (Designator));
6185 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
6187 -- Need delayed freeze if any of the formal types themselves need a
6188 -- delayed freeze and are not yet frozen.
6190 F := First_Formal (Designator);
6191 while Present (F) loop
6192 Possible_Freeze (Etype (F));
6193 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
6197 -- Mark functions that return by reference. Note that it cannot be done
6198 -- for delayed_freeze subprograms because the underlying returned type
6199 -- may not be known yet (for private types).
6201 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
6203 Typ : constant Entity_Id := Etype (Designator);
6204 Utyp : constant Entity_Id := Underlying_Type (Typ);
6207 if Is_Limited_View (Typ) then
6208 Set_Returns_By_Ref (Designator);
6210 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
6211 Set_Returns_By_Ref (Designator);
6215 end Check_Delayed_Subprogram;
6217 ------------------------------------
6218 -- Check_Discriminant_Conformance --
6219 ------------------------------------
6221 procedure Check_Discriminant_Conformance
6226 Old_Discr : Entity_Id := First_Discriminant (Prev);
6227 New_Discr : Node_Id := First (Discriminant_Specifications (N));
6228 New_Discr_Id : Entity_Id;
6229 New_Discr_Type : Entity_Id;
6231 procedure Conformance_Error (Msg : String; N : Node_Id);
6232 -- Post error message for conformance error on given node. Two messages
6233 -- are output. The first points to the previous declaration with a
6234 -- general "no conformance" message. The second is the detailed reason,
6235 -- supplied as Msg. The parameter N provide information for a possible
6236 -- & insertion in the message.
6238 -----------------------
6239 -- Conformance_Error --
6240 -----------------------
6242 procedure Conformance_Error (Msg : String; N : Node_Id) is
6244 Error_Msg_Sloc := Sloc (Prev_Loc);
6245 Error_Msg_N -- CODEFIX
6246 ("not fully conformant with declaration#!", N);
6247 Error_Msg_NE (Msg, N, N);
6248 end Conformance_Error;
6250 -- Start of processing for Check_Discriminant_Conformance
6253 while Present (Old_Discr) and then Present (New_Discr) loop
6254 New_Discr_Id := Defining_Identifier (New_Discr);
6256 -- The subtype mark of the discriminant on the full type has not
6257 -- been analyzed so we do it here. For an access discriminant a new
6260 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
6262 Access_Definition (N, Discriminant_Type (New_Discr));
6265 Find_Type (Discriminant_Type (New_Discr));
6266 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6268 -- Ada 2005: if the discriminant definition carries a null
6269 -- exclusion, create an itype to check properly for consistency
6270 -- with partial declaration.
6272 if Is_Access_Type (New_Discr_Type)
6273 and then Null_Exclusion_Present (New_Discr)
6276 Create_Null_Excluding_Itype
6277 (T => New_Discr_Type,
6278 Related_Nod => New_Discr,
6279 Scope_Id => Current_Scope);
6283 if not Conforming_Types
6284 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6286 Conformance_Error ("type of & does not match!", New_Discr_Id);
6289 -- Treat the new discriminant as an occurrence of the old one,
6290 -- for navigation purposes, and fill in some semantic
6291 -- information, for completeness.
6293 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6294 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6295 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6300 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6301 Conformance_Error ("name & does not match!", New_Discr_Id);
6305 -- Default expressions must match
6308 NewD : constant Boolean :=
6309 Present (Expression (New_Discr));
6310 OldD : constant Boolean :=
6311 Present (Expression (Parent (Old_Discr)));
6314 if NewD or OldD then
6316 -- The old default value has been analyzed and expanded,
6317 -- because the current full declaration will have frozen
6318 -- everything before. The new default values have not been
6319 -- expanded, so expand now to check conformance.
6322 Preanalyze_Spec_Expression
6323 (Expression (New_Discr), New_Discr_Type);
6326 if not (NewD and OldD)
6327 or else not Fully_Conformant_Expressions
6328 (Expression (Parent (Old_Discr)),
6329 Expression (New_Discr))
6333 ("default expression for & does not match!",
6340 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6342 if Ada_Version = Ada_83 then
6344 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6347 -- Grouping (use of comma in param lists) must be the same
6348 -- This is where we catch a misconformance like:
6351 -- A : Integer; B : Integer
6353 -- which are represented identically in the tree except
6354 -- for the setting of the flags More_Ids and Prev_Ids.
6356 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6357 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6360 ("grouping of & does not match!", New_Discr_Id);
6366 Next_Discriminant (Old_Discr);
6370 if Present (Old_Discr) then
6371 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6374 elsif Present (New_Discr) then
6376 ("too many discriminants!", Defining_Identifier (New_Discr));
6379 end Check_Discriminant_Conformance;
6381 ----------------------------
6382 -- Check_Fully_Conformant --
6383 ----------------------------
6385 procedure Check_Fully_Conformant
6386 (New_Id : Entity_Id;
6388 Err_Loc : Node_Id := Empty)
6391 pragma Warnings (Off, Result);
6394 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6395 end Check_Fully_Conformant;
6397 --------------------------
6398 -- Check_Limited_Return --
6399 --------------------------
6401 procedure Check_Limited_Return
6407 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6408 -- replaced by anonymous access results. This is an incompatibility with
6409 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6410 -- controllable with special switch. ???
6412 -- A limited interface that is not immutably limited is OK
6414 if Is_Limited_Interface (R_Type)
6416 not (Is_Task_Interface (R_Type)
6417 or else Is_Protected_Interface (R_Type)
6418 or else Is_Synchronized_Interface (R_Type))
6422 elsif Is_Limited_Type (R_Type)
6423 and then not Is_Interface (R_Type)
6424 and then Comes_From_Source (N)
6425 and then not In_Instance_Body
6426 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6428 -- Error in Ada 2005
6430 if Ada_Version >= Ada_2005
6431 and then not Debug_Flag_Dot_L
6432 and then not GNAT_Mode
6435 ("(Ada 2005) cannot copy object of a limited type "
6436 & "(RM-2005 6.5(5.5/2))", Expr);
6438 if Is_Limited_View (R_Type) then
6440 ("\return by reference not permitted in Ada 2005", Expr);
6443 -- Warn in Ada 95 mode, to give folks a heads up about this
6446 -- In GNAT mode, this is just a warning, to allow it to be evilly
6447 -- turned off. Otherwise it is a real error.
6449 -- In a generic context, simplify the warning because it makes no
6450 -- sense to discuss pass-by-reference or copy.
6452 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6453 if Inside_A_Generic then
6455 ("return of limited object not permitted in Ada 2005 "
6456 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6458 elsif Is_Limited_View (R_Type) then
6460 ("return by reference not permitted in Ada 2005 "
6461 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6464 ("cannot copy object of a limited type in Ada 2005 "
6465 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6468 -- Ada 95 mode, and compatibility warnings disabled
6471 pragma Assert (Ada_Version <= Ada_95);
6472 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6473 return; -- skip continuation messages below
6476 if not Inside_A_Generic then
6478 ("\consider switching to return of access type", Expr);
6479 Explain_Limited_Type (R_Type, Expr);
6482 end Check_Limited_Return;
6484 ---------------------------
6485 -- Check_Mode_Conformant --
6486 ---------------------------
6488 procedure Check_Mode_Conformant
6489 (New_Id : Entity_Id;
6491 Err_Loc : Node_Id := Empty;
6492 Get_Inst : Boolean := False)
6495 pragma Warnings (Off, Result);
6498 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6499 end Check_Mode_Conformant;
6501 --------------------------------
6502 -- Check_Overriding_Indicator --
6503 --------------------------------
6505 procedure Check_Overriding_Indicator
6507 Overridden_Subp : Entity_Id;
6508 Is_Primitive : Boolean)
6514 -- No overriding indicator for literals
6516 if Ekind (Subp) = E_Enumeration_Literal then
6519 elsif Ekind (Subp) = E_Entry then
6520 Decl := Parent (Subp);
6522 -- No point in analyzing a malformed operator
6524 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6525 and then Error_Posted (Subp)
6530 Decl := Unit_Declaration_Node (Subp);
6533 if Nkind_In (Decl, N_Subprogram_Body,
6534 N_Subprogram_Body_Stub,
6535 N_Subprogram_Declaration,
6536 N_Abstract_Subprogram_Declaration,
6537 N_Subprogram_Renaming_Declaration)
6539 Spec := Specification (Decl);
6541 elsif Nkind (Decl) = N_Entry_Declaration then
6548 -- The overriding operation is type conformant with the overridden one,
6549 -- but the names of the formals are not required to match. If the names
6550 -- appear permuted in the overriding operation, this is a possible
6551 -- source of confusion that is worth diagnosing. Controlling formals
6552 -- often carry names that reflect the type, and it is not worthwhile
6553 -- requiring that their names match.
6555 if Present (Overridden_Subp)
6556 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6563 Form1 := First_Formal (Subp);
6564 Form2 := First_Formal (Overridden_Subp);
6566 -- If the overriding operation is a synchronized operation, skip
6567 -- the first parameter of the overridden operation, which is
6568 -- implicit in the new one. If the operation is declared in the
6569 -- body it is not primitive and all formals must match.
6571 if Is_Concurrent_Type (Scope (Subp))
6572 and then Is_Tagged_Type (Scope (Subp))
6573 and then not Has_Completion (Scope (Subp))
6575 Form2 := Next_Formal (Form2);
6578 if Present (Form1) then
6579 Form1 := Next_Formal (Form1);
6580 Form2 := Next_Formal (Form2);
6583 while Present (Form1) loop
6584 if not Is_Controlling_Formal (Form1)
6585 and then Present (Next_Formal (Form2))
6586 and then Chars (Form1) = Chars (Next_Formal (Form2))
6588 Error_Msg_Node_2 := Alias (Overridden_Subp);
6589 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6591 ("& does not match corresponding formal of&#",
6596 Next_Formal (Form1);
6597 Next_Formal (Form2);
6602 -- If there is an overridden subprogram, then check that there is no
6603 -- "not overriding" indicator, and mark the subprogram as overriding.
6605 -- This is not done if the overridden subprogram is marked as hidden,
6606 -- which can occur for the case of inherited controlled operations
6607 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6608 -- subprogram is not itself hidden or we are within a generic instance,
6609 -- in which case the hidden flag may have been modified for the
6610 -- expansion of the instance.
6612 -- (Note: This condition could probably be simplified, leaving out the
6613 -- testing for the specific controlled cases, but it seems safer and
6614 -- clearer this way, and echoes similar special-case tests of this
6615 -- kind in other places.)
6617 if Present (Overridden_Subp)
6618 and then (not Is_Hidden (Overridden_Subp)
6620 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6623 and then Present (Alias (Overridden_Subp))
6624 and then (not Is_Hidden (Alias (Overridden_Subp))
6625 or else In_Instance)))
6627 if Must_Not_Override (Spec) then
6628 Error_Msg_Sloc := Sloc (Overridden_Subp);
6630 if Ekind (Subp) = E_Entry then
6632 ("entry & overrides inherited operation #", Spec, Subp);
6635 ("subprogram & overrides inherited operation #", Spec, Subp);
6638 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6639 -- as an extension of Root_Controlled, and thus has a useless Adjust
6640 -- operation. This operation should not be inherited by other limited
6641 -- controlled types. An explicit Adjust for them is not overriding.
6643 elsif Must_Override (Spec)
6644 and then Chars (Overridden_Subp) = Name_Adjust
6645 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6646 and then Present (Alias (Overridden_Subp))
6647 and then In_Predefined_Unit (Alias (Overridden_Subp))
6650 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6651 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6653 elsif Is_Subprogram (Subp) then
6654 if Is_Init_Proc (Subp) then
6657 elsif No (Overridden_Operation (Subp)) then
6659 -- For entities generated by Derive_Subprograms the overridden
6660 -- operation is the inherited primitive (which is available
6661 -- through the attribute alias)
6663 if (Is_Dispatching_Operation (Subp)
6664 or else Is_Dispatching_Operation (Overridden_Subp))
6665 and then not Comes_From_Source (Overridden_Subp)
6666 and then Find_Dispatching_Type (Overridden_Subp) =
6667 Find_Dispatching_Type (Subp)
6668 and then Present (Alias (Overridden_Subp))
6669 and then Comes_From_Source (Alias (Overridden_Subp))
6671 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6672 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6675 Set_Overridden_Operation (Subp, Overridden_Subp);
6676 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6681 -- If primitive flag is set or this is a protected operation, then
6682 -- the operation is overriding at the point of its declaration, so
6683 -- warn if necessary. Otherwise it may have been declared before the
6684 -- operation it overrides and no check is required.
6687 and then not Must_Override (Spec)
6688 and then (Is_Primitive
6689 or else Ekind (Scope (Subp)) = E_Protected_Type)
6691 Style.Missing_Overriding (Decl, Subp);
6694 -- If Subp is an operator, it may override a predefined operation, if
6695 -- it is defined in the same scope as the type to which it applies.
6696 -- In that case Overridden_Subp is empty because of our implicit
6697 -- representation for predefined operators. We have to check whether the
6698 -- signature of Subp matches that of a predefined operator. Note that
6699 -- first argument provides the name of the operator, and the second
6700 -- argument the signature that may match that of a standard operation.
6701 -- If the indicator is overriding, then the operator must match a
6702 -- predefined signature, because we know already that there is no
6703 -- explicit overridden operation.
6705 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6706 if Must_Not_Override (Spec) then
6708 -- If this is not a primitive or a protected subprogram, then
6709 -- "not overriding" is illegal.
6712 and then Ekind (Scope (Subp)) /= E_Protected_Type
6714 Error_Msg_N ("overriding indicator only allowed "
6715 & "if subprogram is primitive", Subp);
6717 elsif Can_Override_Operator (Subp) then
6719 ("subprogram& overrides predefined operator ", Spec, Subp);
6722 elsif Must_Override (Spec) then
6723 if No (Overridden_Operation (Subp))
6724 and then not Can_Override_Operator (Subp)
6726 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6729 elsif not Error_Posted (Subp)
6730 and then Style_Check
6731 and then Can_Override_Operator (Subp)
6732 and then not In_Predefined_Unit (Subp)
6734 -- If style checks are enabled, indicate that the indicator is
6735 -- missing. However, at the point of declaration, the type of
6736 -- which this is a primitive operation may be private, in which
6737 -- case the indicator would be premature.
6739 if Has_Private_Declaration (Etype (Subp))
6740 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6744 Style.Missing_Overriding (Decl, Subp);
6748 elsif Must_Override (Spec) then
6749 if Ekind (Subp) = E_Entry then
6750 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6752 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6755 -- If the operation is marked "not overriding" and it's not primitive
6756 -- then an error is issued, unless this is an operation of a task or
6757 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6758 -- has been specified have already been checked above.
6760 elsif Must_Not_Override (Spec)
6761 and then not Is_Primitive
6762 and then Ekind (Subp) /= E_Entry
6763 and then Ekind (Scope (Subp)) /= E_Protected_Type
6766 ("overriding indicator only allowed if subprogram is primitive",
6770 end Check_Overriding_Indicator;
6776 -- Note: this procedure needs to know far too much about how the expander
6777 -- messes with exceptions. The use of the flag Exception_Junk and the
6778 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6779 -- works, but is not very clean. It would be better if the expansion
6780 -- routines would leave Original_Node working nicely, and we could use
6781 -- Original_Node here to ignore all the peculiar expander messing ???
6783 procedure Check_Returns
6787 Proc : Entity_Id := Empty)
6791 procedure Check_Statement_Sequence (L : List_Id);
6792 -- Internal recursive procedure to check a list of statements for proper
6793 -- termination by a return statement (or a transfer of control or a
6794 -- compound statement that is itself internally properly terminated).
6796 ------------------------------
6797 -- Check_Statement_Sequence --
6798 ------------------------------
6800 procedure Check_Statement_Sequence (L : List_Id) is
6805 function Assert_False return Boolean;
6806 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6807 -- rewritten as a null statement when assertions are off. The assert
6808 -- is not active, but it is still enough to kill the warning.
6814 function Assert_False return Boolean is
6815 Orig : constant Node_Id := Original_Node (Last_Stm);
6818 if Nkind (Orig) = N_Pragma
6819 and then Pragma_Name (Orig) = Name_Assert
6820 and then not Error_Posted (Orig)
6823 Arg : constant Node_Id :=
6824 First (Pragma_Argument_Associations (Orig));
6825 Exp : constant Node_Id := Expression (Arg);
6827 return Nkind (Exp) = N_Identifier
6828 and then Chars (Exp) = Name_False;
6838 Raise_Exception_Call : Boolean;
6839 -- Set True if statement sequence terminated by Raise_Exception call
6840 -- or a Reraise_Occurrence call.
6842 -- Start of processing for Check_Statement_Sequence
6845 Raise_Exception_Call := False;
6847 -- Get last real statement
6849 Last_Stm := Last (L);
6851 -- Deal with digging out exception handler statement sequences that
6852 -- have been transformed by the local raise to goto optimization.
6853 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6854 -- optimization has occurred, we are looking at something like:
6857 -- original stmts in block
6861 -- goto L1; | omitted if No_Exception_Propagation
6866 -- goto L3; -- skip handler when exception not raised
6868 -- <<L1>> -- target label for local exception
6882 -- and what we have to do is to dig out the estmts1 and estmts2
6883 -- sequences (which were the original sequences of statements in
6884 -- the exception handlers) and check them.
6886 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6891 exit when Nkind (Stm) /= N_Block_Statement;
6892 exit when not Exception_Junk (Stm);
6895 exit when Nkind (Stm) /= N_Label;
6896 exit when not Exception_Junk (Stm);
6897 Check_Statement_Sequence
6898 (Statements (Handled_Statement_Sequence (Next (Stm))));
6903 exit when Nkind (Stm) /= N_Goto_Statement;
6904 exit when not Exception_Junk (Stm);
6908 -- Don't count pragmas
6910 while Nkind (Last_Stm) = N_Pragma
6912 -- Don't count call to SS_Release (can happen after Raise_Exception)
6915 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6917 Nkind (Name (Last_Stm)) = N_Identifier
6919 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6921 -- Don't count exception junk
6924 (Nkind_In (Last_Stm, N_Goto_Statement,
6926 N_Object_Declaration)
6927 and then Exception_Junk (Last_Stm))
6928 or else Nkind (Last_Stm) in N_Push_xxx_Label
6929 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6931 -- Inserted code, such as finalization calls, is irrelevant: we only
6932 -- need to check original source.
6934 or else Is_Rewrite_Insertion (Last_Stm)
6939 -- Here we have the "real" last statement
6941 Kind := Nkind (Last_Stm);
6943 -- Transfer of control, OK. Note that in the No_Return procedure
6944 -- case, we already diagnosed any explicit return statements, so
6945 -- we can treat them as OK in this context.
6947 if Is_Transfer (Last_Stm) then
6950 -- Check cases of explicit non-indirect procedure calls
6952 elsif Kind = N_Procedure_Call_Statement
6953 and then Is_Entity_Name (Name (Last_Stm))
6955 -- Check call to Raise_Exception procedure which is treated
6956 -- specially, as is a call to Reraise_Occurrence.
6958 -- We suppress the warning in these cases since it is likely that
6959 -- the programmer really does not expect to deal with the case
6960 -- of Null_Occurrence, and thus would find a warning about a
6961 -- missing return curious, and raising Program_Error does not
6962 -- seem such a bad behavior if this does occur.
6964 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6965 -- behavior will be to raise Constraint_Error (see AI-329).
6967 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6969 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6971 Raise_Exception_Call := True;
6973 -- For Raise_Exception call, test first argument, if it is
6974 -- an attribute reference for a 'Identity call, then we know
6975 -- that the call cannot possibly return.
6978 Arg : constant Node_Id :=
6979 Original_Node (First_Actual (Last_Stm));
6981 if Nkind (Arg) = N_Attribute_Reference
6982 and then Attribute_Name (Arg) = Name_Identity
6989 -- If statement, need to look inside if there is an else and check
6990 -- each constituent statement sequence for proper termination.
6992 elsif Kind = N_If_Statement
6993 and then Present (Else_Statements (Last_Stm))
6995 Check_Statement_Sequence (Then_Statements (Last_Stm));
6996 Check_Statement_Sequence (Else_Statements (Last_Stm));
6998 if Present (Elsif_Parts (Last_Stm)) then
7000 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
7003 while Present (Elsif_Part) loop
7004 Check_Statement_Sequence (Then_Statements (Elsif_Part));
7012 -- Case statement, check each case for proper termination
7014 elsif Kind = N_Case_Statement then
7018 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
7019 while Present (Case_Alt) loop
7020 Check_Statement_Sequence (Statements (Case_Alt));
7021 Next_Non_Pragma (Case_Alt);
7027 -- Block statement, check its handled sequence of statements
7029 elsif Kind = N_Block_Statement then
7035 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
7044 -- Loop statement. If there is an iteration scheme, we can definitely
7045 -- fall out of the loop. Similarly if there is an exit statement, we
7046 -- can fall out. In either case we need a following return.
7048 elsif Kind = N_Loop_Statement then
7049 if Present (Iteration_Scheme (Last_Stm))
7050 or else Has_Exit (Entity (Identifier (Last_Stm)))
7054 -- A loop with no exit statement or iteration scheme is either
7055 -- an infinite loop, or it has some other exit (raise/return).
7056 -- In either case, no warning is required.
7062 -- Timed entry call, check entry call and delay alternatives
7064 -- Note: in expanded code, the timed entry call has been converted
7065 -- to a set of expanded statements on which the check will work
7066 -- correctly in any case.
7068 elsif Kind = N_Timed_Entry_Call then
7070 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
7071 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
7074 -- If statement sequence of entry call alternative is missing,
7075 -- then we can definitely fall through, and we post the error
7076 -- message on the entry call alternative itself.
7078 if No (Statements (ECA)) then
7081 -- If statement sequence of delay alternative is missing, then
7082 -- we can definitely fall through, and we post the error
7083 -- message on the delay alternative itself.
7085 -- Note: if both ECA and DCA are missing the return, then we
7086 -- post only one message, should be enough to fix the bugs.
7087 -- If not we will get a message next time on the DCA when the
7090 elsif No (Statements (DCA)) then
7093 -- Else check both statement sequences
7096 Check_Statement_Sequence (Statements (ECA));
7097 Check_Statement_Sequence (Statements (DCA));
7102 -- Conditional entry call, check entry call and else part
7104 -- Note: in expanded code, the conditional entry call has been
7105 -- converted to a set of expanded statements on which the check
7106 -- will work correctly in any case.
7108 elsif Kind = N_Conditional_Entry_Call then
7110 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
7113 -- If statement sequence of entry call alternative is missing,
7114 -- then we can definitely fall through, and we post the error
7115 -- message on the entry call alternative itself.
7117 if No (Statements (ECA)) then
7120 -- Else check statement sequence and else part
7123 Check_Statement_Sequence (Statements (ECA));
7124 Check_Statement_Sequence (Else_Statements (Last_Stm));
7130 -- If we fall through, issue appropriate message
7134 -- Kill warning if last statement is a raise exception call,
7135 -- or a pragma Assert (False). Note that with assertions enabled,
7136 -- such a pragma has been converted into a raise exception call
7137 -- already, so the Assert_False is for the assertions off case.
7139 if not Raise_Exception_Call and then not Assert_False then
7141 -- In GNATprove mode, it is an error to have a missing return
7143 Error_Msg_Warn := SPARK_Mode /= On;
7145 -- Issue error message or warning
7148 ("RETURN statement missing following this statement<<!",
7151 ("\Program_Error ]<<!", Last_Stm);
7154 -- Note: we set Err even though we have not issued a warning
7155 -- because we still have a case of a missing return. This is
7156 -- an extremely marginal case, probably will never be noticed
7157 -- but we might as well get it right.
7161 -- Otherwise we have the case of a procedure marked No_Return
7164 if not Raise_Exception_Call then
7165 if GNATprove_Mode then
7167 ("implied return after this statement would have raised "
7168 & "Program_Error", Last_Stm);
7170 -- In normal compilation mode, do not warn on a generated call
7171 -- (e.g. in the body of a renaming as completion).
7173 elsif Comes_From_Source (Last_Stm) then
7175 ("implied return after this statement will raise "
7176 & "Program_Error??", Last_Stm);
7179 Error_Msg_Warn := SPARK_Mode /= On;
7181 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
7185 RE : constant Node_Id :=
7186 Make_Raise_Program_Error (Sloc (Last_Stm),
7187 Reason => PE_Implicit_Return);
7189 Insert_After (Last_Stm, RE);
7193 end Check_Statement_Sequence;
7195 -- Start of processing for Check_Returns
7199 Check_Statement_Sequence (Statements (HSS));
7201 if Present (Exception_Handlers (HSS)) then
7202 Handler := First_Non_Pragma (Exception_Handlers (HSS));
7203 while Present (Handler) loop
7204 Check_Statement_Sequence (Statements (Handler));
7205 Next_Non_Pragma (Handler);
7210 ----------------------------
7211 -- Check_Subprogram_Order --
7212 ----------------------------
7214 procedure Check_Subprogram_Order (N : Node_Id) is
7216 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
7217 -- This is used to check if S1 > S2 in the sense required by this test,
7218 -- for example nameab < namec, but name2 < name10.
7220 -----------------------------
7221 -- Subprogram_Name_Greater --
7222 -----------------------------
7224 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
7229 -- Deal with special case where names are identical except for a
7230 -- numerical suffix. These are handled specially, taking the numeric
7231 -- ordering from the suffix into account.
7234 while S1 (L1) in '0' .. '9' loop
7239 while S2 (L2) in '0' .. '9' loop
7243 -- If non-numeric parts non-equal, do straight compare
7245 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
7248 -- If non-numeric parts equal, compare suffixed numeric parts. Note
7249 -- that a missing suffix is treated as numeric zero in this test.
7253 while L1 < S1'Last loop
7255 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
7259 while L2 < S2'Last loop
7261 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
7266 end Subprogram_Name_Greater;
7268 -- Start of processing for Check_Subprogram_Order
7271 -- Check body in alpha order if this is option
7274 and then Style_Check_Order_Subprograms
7275 and then Nkind (N) = N_Subprogram_Body
7276 and then Comes_From_Source (N)
7277 and then In_Extended_Main_Source_Unit (N)
7281 renames Scope_Stack.Table
7282 (Scope_Stack.Last).Last_Subprogram_Name;
7284 Body_Id : constant Entity_Id :=
7285 Defining_Entity (Specification (N));
7288 Get_Decoded_Name_String (Chars (Body_Id));
7291 if Subprogram_Name_Greater
7292 (LSN.all, Name_Buffer (1 .. Name_Len))
7294 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7300 LSN := new String'(Name_Buffer (1 .. Name_Len));
7303 end Check_Subprogram_Order;
7305 ------------------------------
7306 -- Check_Subtype_Conformant --
7307 ------------------------------
7309 procedure Check_Subtype_Conformant
7310 (New_Id : Entity_Id;
7312 Err_Loc : Node_Id := Empty;
7313 Skip_Controlling_Formals : Boolean := False;
7314 Get_Inst : Boolean := False)
7317 pragma Warnings (Off, Result);
7320 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7321 Skip_Controlling_Formals => Skip_Controlling_Formals,
7322 Get_Inst => Get_Inst);
7323 end Check_Subtype_Conformant;
7325 -----------------------------------
7326 -- Check_Synchronized_Overriding --
7327 -----------------------------------
7329 procedure Check_Synchronized_Overriding
7330 (Def_Id : Entity_Id;
7331 Overridden_Subp : out Entity_Id)
7333 Ifaces_List : Elist_Id;
7337 function Is_Valid_Formal (F : Entity_Id) return Boolean;
7338 -- Predicate for legality rule in 9.4 (11.9/2): If an inherited
7339 -- subprogram is implemented by a protected procedure or entry,
7340 -- its first parameter must be out, in out, or access-to-variable.
7342 function Matches_Prefixed_View_Profile
7343 (Prim_Params : List_Id;
7344 Iface_Params : List_Id) return Boolean;
7345 -- Determine whether a subprogram's parameter profile Prim_Params
7346 -- matches that of a potentially overridden interface subprogram
7347 -- Iface_Params. Also determine if the type of first parameter of
7348 -- Iface_Params is an implemented interface.
7350 ----------------------
7351 -- Is_Valid_Formal --
7352 ----------------------
7354 function Is_Valid_Formal (F : Entity_Id) return Boolean is
7357 Ekind_In (F, E_In_Out_Parameter, E_Out_Parameter)
7359 (Nkind (Parameter_Type (Parent (F))) = N_Access_Definition
7360 and then not Constant_Present (Parameter_Type (Parent (F))));
7361 end Is_Valid_Formal;
7363 -----------------------------------
7364 -- Matches_Prefixed_View_Profile --
7365 -----------------------------------
7367 function Matches_Prefixed_View_Profile
7368 (Prim_Params : List_Id;
7369 Iface_Params : List_Id) return Boolean
7371 function Is_Implemented
7372 (Ifaces_List : Elist_Id;
7373 Iface : Entity_Id) return Boolean;
7374 -- Determine if Iface is implemented by the current task or
7377 --------------------
7378 -- Is_Implemented --
7379 --------------------
7381 function Is_Implemented
7382 (Ifaces_List : Elist_Id;
7383 Iface : Entity_Id) return Boolean
7385 Iface_Elmt : Elmt_Id;
7388 Iface_Elmt := First_Elmt (Ifaces_List);
7389 while Present (Iface_Elmt) loop
7390 if Node (Iface_Elmt) = Iface then
7394 Next_Elmt (Iface_Elmt);
7402 Iface_Id : Entity_Id;
7403 Iface_Param : Node_Id;
7404 Iface_Typ : Entity_Id;
7405 Prim_Id : Entity_Id;
7406 Prim_Param : Node_Id;
7407 Prim_Typ : Entity_Id;
7409 -- Start of processing for Matches_Prefixed_View_Profile
7412 Iface_Param := First (Iface_Params);
7413 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7415 if Is_Access_Type (Iface_Typ) then
7416 Iface_Typ := Designated_Type (Iface_Typ);
7419 Prim_Param := First (Prim_Params);
7421 -- The first parameter of the potentially overridden subprogram must
7422 -- be an interface implemented by Prim.
7424 if not Is_Interface (Iface_Typ)
7425 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7430 -- The checks on the object parameters are done, so move on to the
7431 -- rest of the parameters.
7433 if not In_Scope then
7434 Prim_Param := Next (Prim_Param);
7437 Iface_Param := Next (Iface_Param);
7438 while Present (Iface_Param) and then Present (Prim_Param) loop
7439 Iface_Id := Defining_Identifier (Iface_Param);
7440 Iface_Typ := Find_Parameter_Type (Iface_Param);
7442 Prim_Id := Defining_Identifier (Prim_Param);
7443 Prim_Typ := Find_Parameter_Type (Prim_Param);
7445 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7446 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7447 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7449 Iface_Typ := Designated_Type (Iface_Typ);
7450 Prim_Typ := Designated_Type (Prim_Typ);
7453 -- Case of multiple interface types inside a parameter profile
7455 -- (Obj_Param : in out Iface; ...; Param : Iface)
7457 -- If the interface type is implemented, then the matching type in
7458 -- the primitive should be the implementing record type.
7460 if Ekind (Iface_Typ) = E_Record_Type
7461 and then Is_Interface (Iface_Typ)
7462 and then Is_Implemented (Ifaces_List, Iface_Typ)
7464 if Prim_Typ /= Typ then
7468 -- The two parameters must be both mode and subtype conformant
7470 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7472 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7481 -- One of the two lists contains more parameters than the other
7483 if Present (Iface_Param) or else Present (Prim_Param) then
7488 end Matches_Prefixed_View_Profile;
7490 -- Start of processing for Check_Synchronized_Overriding
7493 Overridden_Subp := Empty;
7495 -- Def_Id must be an entry or a subprogram. We should skip predefined
7496 -- primitives internally generated by the front end; however at this
7497 -- stage predefined primitives are still not fully decorated. As a
7498 -- minor optimization we skip here internally generated subprograms.
7500 if (Ekind (Def_Id) /= E_Entry
7501 and then Ekind (Def_Id) /= E_Function
7502 and then Ekind (Def_Id) /= E_Procedure)
7503 or else not Comes_From_Source (Def_Id)
7508 -- Search for the concurrent declaration since it contains the list of
7509 -- all implemented interfaces. In this case, the subprogram is declared
7510 -- within the scope of a protected or a task type.
7512 if Present (Scope (Def_Id))
7513 and then Is_Concurrent_Type (Scope (Def_Id))
7514 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7516 Typ := Scope (Def_Id);
7519 -- The enclosing scope is not a synchronized type and the subprogram
7522 elsif No (First_Formal (Def_Id)) then
7525 -- The subprogram has formals and hence it may be a primitive of a
7529 Typ := Etype (First_Formal (Def_Id));
7531 if Is_Access_Type (Typ) then
7532 Typ := Directly_Designated_Type (Typ);
7535 if Is_Concurrent_Type (Typ)
7536 and then not Is_Generic_Actual_Type (Typ)
7540 -- This case occurs when the concurrent type is declared within a
7541 -- generic unit. As a result the corresponding record has been built
7542 -- and used as the type of the first formal, we just have to retrieve
7543 -- the corresponding concurrent type.
7545 elsif Is_Concurrent_Record_Type (Typ)
7546 and then not Is_Class_Wide_Type (Typ)
7547 and then Present (Corresponding_Concurrent_Type (Typ))
7549 Typ := Corresponding_Concurrent_Type (Typ);
7557 -- There is no overriding to check if this is an inherited operation in
7558 -- a type derivation for a generic actual.
7560 Collect_Interfaces (Typ, Ifaces_List);
7562 if Is_Empty_Elmt_List (Ifaces_List) then
7566 -- Determine whether entry or subprogram Def_Id overrides a primitive
7567 -- operation that belongs to one of the interfaces in Ifaces_List.
7570 Candidate : Entity_Id := Empty;
7571 Hom : Entity_Id := Empty;
7572 Subp : Entity_Id := Empty;
7575 -- Traverse the homonym chain, looking for a potentially overridden
7576 -- subprogram that belongs to an implemented interface.
7578 Hom := Current_Entity_In_Scope (Def_Id);
7579 while Present (Hom) loop
7583 or else not Is_Overloadable (Subp)
7584 or else not Is_Primitive (Subp)
7585 or else not Is_Dispatching_Operation (Subp)
7586 or else not Present (Find_Dispatching_Type (Subp))
7587 or else not Is_Interface (Find_Dispatching_Type (Subp))
7591 -- Entries and procedures can override abstract or null interface
7594 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7595 and then Ekind (Subp) = E_Procedure
7596 and then Matches_Prefixed_View_Profile
7597 (Parameter_Specifications (Parent (Def_Id)),
7598 Parameter_Specifications (Parent (Subp)))
7602 -- For an overridden subprogram Subp, check whether the mode
7603 -- of its first parameter is correct depending on the kind of
7604 -- synchronized type.
7607 Formal : constant Node_Id := First_Formal (Candidate);
7610 -- In order for an entry or a protected procedure to
7611 -- override, the first parameter of the overridden routine
7612 -- must be of mode "out", "in out", or access-to-variable.
7614 if Ekind_In (Candidate, E_Entry, E_Procedure)
7615 and then Is_Protected_Type (Typ)
7616 and then not Is_Valid_Formal (Formal)
7620 -- All other cases are OK since a task entry or routine does
7621 -- not have a restriction on the mode of the first parameter
7622 -- of the overridden interface routine.
7625 Overridden_Subp := Candidate;
7630 -- Functions can override abstract interface functions. Return
7631 -- types must be subtype conformant.
7633 elsif Ekind (Def_Id) = E_Function
7634 and then Ekind (Subp) = E_Function
7635 and then Matches_Prefixed_View_Profile
7636 (Parameter_Specifications (Parent (Def_Id)),
7637 Parameter_Specifications (Parent (Subp)))
7638 and then Conforming_Types
7639 (Etype (Def_Id), Etype (Subp), Subtype_Conformant)
7643 -- If an inherited subprogram is implemented by a protected
7644 -- function, then the first parameter of the inherited
7645 -- subprogram shall be of mode in, but not an access-to-
7646 -- variable parameter (RM 9.4(11/9)).
7648 if Present (First_Formal (Subp))
7649 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7651 (not Is_Access_Type (Etype (First_Formal (Subp)))
7653 Is_Access_Constant (Etype (First_Formal (Subp))))
7655 Overridden_Subp := Subp;
7660 Hom := Homonym (Hom);
7663 -- After examining all candidates for overriding, we are left with
7664 -- the best match, which is a mode-incompatible interface routine.
7666 if In_Scope and then Present (Candidate) then
7667 Error_Msg_PT (Def_Id, Candidate);
7670 Overridden_Subp := Candidate;
7673 end Check_Synchronized_Overriding;
7675 ---------------------------
7676 -- Check_Type_Conformant --
7677 ---------------------------
7679 procedure Check_Type_Conformant
7680 (New_Id : Entity_Id;
7682 Err_Loc : Node_Id := Empty)
7685 pragma Warnings (Off, Result);
7688 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7689 end Check_Type_Conformant;
7691 ---------------------------
7692 -- Can_Override_Operator --
7693 ---------------------------
7695 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7699 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7703 Typ := Base_Type (Etype (First_Formal (Subp)));
7705 -- Check explicitly that the operation is a primitive of the type
7707 return Operator_Matches_Spec (Subp, Subp)
7708 and then not Is_Generic_Type (Typ)
7709 and then Scope (Subp) = Scope (Typ)
7710 and then not Is_Class_Wide_Type (Typ);
7712 end Can_Override_Operator;
7714 ----------------------
7715 -- Conforming_Types --
7716 ----------------------
7718 function Conforming_Types
7721 Ctype : Conformance_Type;
7722 Get_Inst : Boolean := False) return Boolean
7724 function Base_Types_Match
7726 Typ_2 : Entity_Id) return Boolean;
7727 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7728 -- in different scopes (e.g. parent and child instances), then verify
7729 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7730 -- the same subtype chain. The whole purpose of this procedure is to
7731 -- prevent spurious ambiguities in an instantiation that may arise if
7732 -- two distinct generic types are instantiated with the same actual.
7734 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7735 -- An access parameter can designate an incomplete type. If the
7736 -- incomplete type is the limited view of a type from a limited_
7737 -- with_clause, check whether the non-limited view is available.
7738 -- If it is a (non-limited) incomplete type, get the full view.
7740 function Matches_Limited_With_View
7742 Typ_2 : Entity_Id) return Boolean;
7743 -- Returns True if and only if either Typ_1 denotes a limited view of
7744 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7745 -- the limited with view of a type is used in a subprogram declaration
7746 -- and the subprogram body is in the scope of a regular with clause for
7747 -- the same unit. In such a case, the two type entities are considered
7748 -- identical for purposes of conformance checking.
7750 ----------------------
7751 -- Base_Types_Match --
7752 ----------------------
7754 function Base_Types_Match
7756 Typ_2 : Entity_Id) return Boolean
7758 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7759 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7762 if Typ_1 = Typ_2 then
7765 elsif Base_1 = Base_2 then
7767 -- The following is too permissive. A more precise test should
7768 -- check that the generic actual is an ancestor subtype of the
7771 -- See code in Find_Corresponding_Spec that applies an additional
7772 -- filter to handle accidental amiguities in instances.
7775 not Is_Generic_Actual_Type (Typ_1)
7776 or else not Is_Generic_Actual_Type (Typ_2)
7777 or else Scope (Typ_1) /= Scope (Typ_2);
7779 -- If Typ_2 is a generic actual type it is declared as the subtype of
7780 -- the actual. If that actual is itself a subtype we need to use its
7781 -- own base type to check for compatibility.
7783 elsif Ekind (Base_2) = Ekind (Typ_2)
7784 and then Base_1 = Base_Type (Base_2)
7788 elsif Ekind (Base_1) = Ekind (Typ_1)
7789 and then Base_2 = Base_Type (Base_1)
7796 end Base_Types_Match;
7798 --------------------------
7799 -- Find_Designated_Type --
7800 --------------------------
7802 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7806 Desig := Directly_Designated_Type (Typ);
7808 if Ekind (Desig) = E_Incomplete_Type then
7810 -- If regular incomplete type, get full view if available
7812 if Present (Full_View (Desig)) then
7813 Desig := Full_View (Desig);
7815 -- If limited view of a type, get non-limited view if available,
7816 -- and check again for a regular incomplete type.
7818 elsif Present (Non_Limited_View (Desig)) then
7819 Desig := Get_Full_View (Non_Limited_View (Desig));
7824 end Find_Designated_Type;
7826 -------------------------------
7827 -- Matches_Limited_With_View --
7828 -------------------------------
7830 function Matches_Limited_With_View
7832 Typ_2 : Entity_Id) return Boolean
7834 function Is_Matching_Limited_View
7836 View : Entity_Id) return Boolean;
7837 -- Determine whether non-limited view View denotes type Typ in some
7838 -- conformant fashion.
7840 ------------------------------
7841 -- Is_Matching_Limited_View --
7842 ------------------------------
7844 function Is_Matching_Limited_View
7846 View : Entity_Id) return Boolean
7848 Root_Typ : Entity_Id;
7849 Root_View : Entity_Id;
7852 -- The non-limited view directly denotes the type
7857 -- The type is a subtype of the non-limited view
7859 elsif Is_Subtype_Of (Typ, View) then
7862 -- Both the non-limited view and the type denote class-wide types
7864 elsif Is_Class_Wide_Type (Typ)
7865 and then Is_Class_Wide_Type (View)
7867 Root_Typ := Root_Type (Typ);
7868 Root_View := Root_Type (View);
7870 if Root_Typ = Root_View then
7873 -- An incomplete tagged type and its full view may receive two
7874 -- distinct class-wide types when the related package has not
7875 -- been analyzed yet.
7878 -- type T is tagged; -- CW_1
7879 -- type T is tagged null record; -- CW_2
7882 -- This is because the package lacks any semantic information
7883 -- that may eventually link both views of T. As a consequence,
7884 -- a client of the limited view of Pack will see CW_2 while a
7885 -- client of the non-limited view of Pack will see CW_1.
7887 elsif Is_Incomplete_Type (Root_Typ)
7888 and then Present (Full_View (Root_Typ))
7889 and then Full_View (Root_Typ) = Root_View
7893 elsif Is_Incomplete_Type (Root_View)
7894 and then Present (Full_View (Root_View))
7895 and then Full_View (Root_View) = Root_Typ
7902 end Is_Matching_Limited_View;
7904 -- Start of processing for Matches_Limited_With_View
7907 -- In some cases a type imported through a limited_with clause, and
7908 -- its non-limited view are both visible, for example in an anonymous
7909 -- access-to-class-wide type in a formal, or when building the body
7910 -- for a subprogram renaming after the subprogram has been frozen.
7911 -- In these cases both entities designate the same type. In addition,
7912 -- if one of them is an actual in an instance, it may be a subtype of
7913 -- the non-limited view of the other.
7915 if From_Limited_With (Typ_1)
7916 and then From_Limited_With (Typ_2)
7917 and then Available_View (Typ_1) = Available_View (Typ_2)
7921 elsif From_Limited_With (Typ_1) then
7922 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7924 elsif From_Limited_With (Typ_2) then
7925 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7930 end Matches_Limited_With_View;
7934 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7936 Type_1 : Entity_Id := T1;
7937 Type_2 : Entity_Id := T2;
7939 -- Start of processing for Conforming_Types
7942 -- The context is an instance association for a formal access-to-
7943 -- subprogram type; the formal parameter types require mapping because
7944 -- they may denote other formal parameters of the generic unit.
7947 Type_1 := Get_Instance_Of (T1);
7948 Type_2 := Get_Instance_Of (T2);
7951 -- If one of the types is a view of the other introduced by a limited
7952 -- with clause, treat these as conforming for all purposes.
7954 if Matches_Limited_With_View (T1, T2) then
7957 elsif Base_Types_Match (Type_1, Type_2) then
7958 if Ctype <= Mode_Conformant then
7963 Subtypes_Statically_Match (Type_1, Type_2)
7964 and then Dimensions_Match (Type_1, Type_2);
7967 elsif Is_Incomplete_Or_Private_Type (Type_1)
7968 and then Present (Full_View (Type_1))
7969 and then Base_Types_Match (Full_View (Type_1), Type_2)
7972 Ctype <= Mode_Conformant
7973 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7975 elsif Ekind (Type_2) = E_Incomplete_Type
7976 and then Present (Full_View (Type_2))
7977 and then Base_Types_Match (Type_1, Full_View (Type_2))
7980 Ctype <= Mode_Conformant
7981 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7983 elsif Is_Private_Type (Type_2)
7984 and then In_Instance
7985 and then Present (Full_View (Type_2))
7986 and then Base_Types_Match (Type_1, Full_View (Type_2))
7989 Ctype <= Mode_Conformant
7990 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7992 -- Another confusion between views in a nested instance with an
7993 -- actual private type whose full view is not in scope.
7995 elsif Ekind (Type_2) = E_Private_Subtype
7996 and then In_Instance
7997 and then Etype (Type_2) = Type_1
8001 -- In Ada 2012, incomplete types (including limited views) can appear
8002 -- as actuals in instantiations, where they are conformant to the
8003 -- corresponding incomplete formal.
8005 elsif Is_Incomplete_Type (Type_1)
8006 and then Is_Incomplete_Type (Type_2)
8007 and then In_Instance
8008 and then (Used_As_Generic_Actual (Type_1)
8009 or else Used_As_Generic_Actual (Type_2))
8014 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
8015 -- treated recursively because they carry a signature. As far as
8016 -- conformance is concerned, convention plays no role, and either
8017 -- or both could be access to protected subprograms.
8019 Are_Anonymous_Access_To_Subprogram_Types :=
8020 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
8021 E_Anonymous_Access_Protected_Subprogram_Type)
8023 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
8024 E_Anonymous_Access_Protected_Subprogram_Type);
8026 -- Test anonymous access type case. For this case, static subtype
8027 -- matching is required for mode conformance (RM 6.3.1(15)). We check
8028 -- the base types because we may have built internal subtype entities
8029 -- to handle null-excluding types (see Process_Formals).
8031 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
8033 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
8035 -- Ada 2005 (AI-254)
8037 or else Are_Anonymous_Access_To_Subprogram_Types
8040 Desig_1 : Entity_Id;
8041 Desig_2 : Entity_Id;
8044 -- In Ada 2005, access constant indicators must match for
8045 -- subtype conformance.
8047 if Ada_Version >= Ada_2005
8048 and then Ctype >= Subtype_Conformant
8050 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
8055 Desig_1 := Find_Designated_Type (Type_1);
8056 Desig_2 := Find_Designated_Type (Type_2);
8058 -- If the context is an instance association for a formal
8059 -- access-to-subprogram type; formal access parameter designated
8060 -- types require mapping because they may denote other formal
8061 -- parameters of the generic unit.
8064 Desig_1 := Get_Instance_Of (Desig_1);
8065 Desig_2 := Get_Instance_Of (Desig_2);
8068 -- It is possible for a Class_Wide_Type to be introduced for an
8069 -- incomplete type, in which case there is a separate class_ wide
8070 -- type for the full view. The types conform if their Etypes
8071 -- conform, i.e. one may be the full view of the other. This can
8072 -- only happen in the context of an access parameter, other uses
8073 -- of an incomplete Class_Wide_Type are illegal.
8075 if Is_Class_Wide_Type (Desig_1)
8077 Is_Class_Wide_Type (Desig_2)
8081 (Etype (Base_Type (Desig_1)),
8082 Etype (Base_Type (Desig_2)), Ctype);
8084 elsif Are_Anonymous_Access_To_Subprogram_Types then
8085 if Ada_Version < Ada_2005 then
8087 Ctype = Type_Conformant
8088 or else Subtypes_Statically_Match (Desig_1, Desig_2);
8090 -- We must check the conformance of the signatures themselves
8094 Conformant : Boolean;
8097 (Desig_1, Desig_2, Ctype, False, Conformant);
8102 -- A limited view of an actual matches the corresponding
8103 -- incomplete formal.
8105 elsif Ekind (Desig_2) = E_Incomplete_Subtype
8106 and then From_Limited_With (Desig_2)
8107 and then Used_As_Generic_Actual (Etype (Desig_2))
8112 return Base_Type (Desig_1) = Base_Type (Desig_2)
8113 and then (Ctype = Type_Conformant
8115 Subtypes_Statically_Match (Desig_1, Desig_2));
8119 -- Otherwise definitely no match
8122 if ((Ekind (Type_1) = E_Anonymous_Access_Type
8123 and then Is_Access_Type (Type_2))
8124 or else (Ekind (Type_2) = E_Anonymous_Access_Type
8125 and then Is_Access_Type (Type_1)))
8128 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
8130 May_Hide_Profile := True;
8135 end Conforming_Types;
8137 --------------------------
8138 -- Create_Extra_Formals --
8139 --------------------------
8141 procedure Create_Extra_Formals (E : Entity_Id) is
8142 First_Extra : Entity_Id := Empty;
8144 Last_Extra : Entity_Id := Empty;
8146 function Add_Extra_Formal
8147 (Assoc_Entity : Entity_Id;
8150 Suffix : String) return Entity_Id;
8151 -- Add an extra formal to the current list of formals and extra formals.
8152 -- The extra formal is added to the end of the list of extra formals,
8153 -- and also returned as the result. These formals are always of mode IN.
8154 -- The new formal has the type Typ, is declared in Scope, and its name
8155 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
8156 -- The following suffixes are currently used. They should not be changed
8157 -- without coordinating with CodePeer, which makes use of these to
8158 -- provide better messages.
8160 -- O denotes the Constrained bit.
8161 -- L denotes the accessibility level.
8162 -- BIP_xxx denotes an extra formal for a build-in-place function. See
8163 -- the full list in exp_ch6.BIP_Formal_Kind.
8165 ----------------------
8166 -- Add_Extra_Formal --
8167 ----------------------
8169 function Add_Extra_Formal
8170 (Assoc_Entity : Entity_Id;
8173 Suffix : String) return Entity_Id
8175 EF : constant Entity_Id :=
8176 Make_Defining_Identifier (Sloc (Assoc_Entity),
8177 Chars => New_External_Name (Chars (Assoc_Entity),
8181 -- A little optimization. Never generate an extra formal for the
8182 -- _init operand of an initialization procedure, since it could
8185 if Chars (Formal) = Name_uInit then
8189 Set_Ekind (EF, E_In_Parameter);
8190 Set_Actual_Subtype (EF, Typ);
8191 Set_Etype (EF, Typ);
8192 Set_Scope (EF, Scope);
8193 Set_Mechanism (EF, Default_Mechanism);
8194 Set_Formal_Validity (EF);
8196 if No (First_Extra) then
8198 Set_Extra_Formals (Scope, EF);
8201 if Present (Last_Extra) then
8202 Set_Extra_Formal (Last_Extra, EF);
8208 end Add_Extra_Formal;
8212 Formal_Type : Entity_Id;
8213 P_Formal : Entity_Id := Empty;
8215 -- Start of processing for Create_Extra_Formals
8218 -- We never generate extra formals if expansion is not active because we
8219 -- don't need them unless we are generating code.
8221 if not Expander_Active then
8225 -- No need to generate extra formals in interface thunks whose target
8226 -- primitive has no extra formals.
8228 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
8232 -- If this is a derived subprogram then the subtypes of the parent
8233 -- subprogram's formal parameters will be used to determine the need
8234 -- for extra formals.
8236 if Is_Overloadable (E) and then Present (Alias (E)) then
8237 P_Formal := First_Formal (Alias (E));
8240 Formal := First_Formal (E);
8241 while Present (Formal) loop
8242 Last_Extra := Formal;
8243 Next_Formal (Formal);
8246 -- If Extra_Formals were already created, don't do it again. This
8247 -- situation may arise for subprogram types created as part of
8248 -- dispatching calls (see Expand_Dispatching_Call).
8250 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
8254 -- If the subprogram is a predefined dispatching subprogram then don't
8255 -- generate any extra constrained or accessibility level formals. In
8256 -- general we suppress these for internal subprograms (by not calling
8257 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
8258 -- generated stream attributes do get passed through because extra
8259 -- build-in-place formals are needed in some cases (limited 'Input).
8261 if Is_Predefined_Internal_Operation (E) then
8262 goto Test_For_Func_Result_Extras;
8265 Formal := First_Formal (E);
8266 while Present (Formal) loop
8268 -- Create extra formal for supporting the attribute 'Constrained.
8269 -- The case of a private type view without discriminants also
8270 -- requires the extra formal if the underlying type has defaulted
8273 if Ekind (Formal) /= E_In_Parameter then
8274 if Present (P_Formal) then
8275 Formal_Type := Etype (P_Formal);
8277 Formal_Type := Etype (Formal);
8280 -- Do not produce extra formals for Unchecked_Union parameters.
8281 -- Jump directly to the end of the loop.
8283 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
8284 goto Skip_Extra_Formal_Generation;
8287 if not Has_Discriminants (Formal_Type)
8288 and then Ekind (Formal_Type) in Private_Kind
8289 and then Present (Underlying_Type (Formal_Type))
8291 Formal_Type := Underlying_Type (Formal_Type);
8294 -- Suppress the extra formal if formal's subtype is constrained or
8295 -- indefinite, or we're compiling for Ada 2012 and the underlying
8296 -- type is tagged and limited. In Ada 2012, a limited tagged type
8297 -- can have defaulted discriminants, but 'Constrained is required
8298 -- to return True, so the formal is never needed (see AI05-0214).
8299 -- Note that this ensures consistency of calling sequences for
8300 -- dispatching operations when some types in a class have defaults
8301 -- on discriminants and others do not (and requiring the extra
8302 -- formal would introduce distributed overhead).
8304 -- If the type does not have a completion yet, treat as prior to
8305 -- Ada 2012 for consistency.
8307 if Has_Discriminants (Formal_Type)
8308 and then not Is_Constrained (Formal_Type)
8309 and then Is_Definite_Subtype (Formal_Type)
8310 and then (Ada_Version < Ada_2012
8311 or else No (Underlying_Type (Formal_Type))
8313 (Is_Limited_Type (Formal_Type)
8316 (Underlying_Type (Formal_Type)))))
8318 Set_Extra_Constrained
8319 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8323 -- Create extra formal for supporting accessibility checking. This
8324 -- is done for both anonymous access formals and formals of named
8325 -- access types that are marked as controlling formals. The latter
8326 -- case can occur when Expand_Dispatching_Call creates a subprogram
8327 -- type and substitutes the types of access-to-class-wide actuals
8328 -- for the anonymous access-to-specific-type of controlling formals.
8329 -- Base_Type is applied because in cases where there is a null
8330 -- exclusion the formal may have an access subtype.
8332 -- This is suppressed if we specifically suppress accessibility
8333 -- checks at the package level for either the subprogram, or the
8334 -- package in which it resides. However, we do not suppress it
8335 -- simply if the scope has accessibility checks suppressed, since
8336 -- this could cause trouble when clients are compiled with a
8337 -- different suppression setting. The explicit checks at the
8338 -- package level are safe from this point of view.
8340 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8341 or else (Is_Controlling_Formal (Formal)
8342 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8344 (Explicit_Suppress (E, Accessibility_Check)
8346 Explicit_Suppress (Scope (E), Accessibility_Check))
8349 or else Present (Extra_Accessibility (P_Formal)))
8351 Set_Extra_Accessibility
8352 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8355 -- This label is required when skipping extra formal generation for
8356 -- Unchecked_Union parameters.
8358 <<Skip_Extra_Formal_Generation>>
8360 if Present (P_Formal) then
8361 Next_Formal (P_Formal);
8364 Next_Formal (Formal);
8367 <<Test_For_Func_Result_Extras>>
8369 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8370 -- function call is ... determined by the point of call ...".
8372 if Needs_Result_Accessibility_Level (E) then
8373 Set_Extra_Accessibility_Of_Result
8374 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8377 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8378 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8380 if Is_Build_In_Place_Function (E) then
8382 Result_Subt : constant Entity_Id := Etype (E);
8383 Formal_Typ : Entity_Id;
8384 Subp_Decl : Node_Id;
8385 Discard : Entity_Id;
8388 -- In the case of functions with unconstrained result subtypes,
8389 -- add a 4-state formal indicating whether the return object is
8390 -- allocated by the caller (1), or should be allocated by the
8391 -- callee on the secondary stack (2), in the global heap (3), or
8392 -- in a user-defined storage pool (4). For the moment we just use
8393 -- Natural for the type of this formal. Note that this formal
8394 -- isn't usually needed in the case where the result subtype is
8395 -- constrained, but it is needed when the function has a tagged
8396 -- result, because generally such functions can be called in a
8397 -- dispatching context and such calls must be handled like calls
8398 -- to a class-wide function.
8400 if Needs_BIP_Alloc_Form (E) then
8403 (E, Standard_Natural,
8404 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8406 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8407 -- use a user-defined pool. This formal is not added on
8408 -- ZFP as those targets do not support pools.
8410 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8413 (E, RTE (RE_Root_Storage_Pool_Ptr),
8414 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8418 -- In the case of functions whose result type needs finalization,
8419 -- add an extra formal which represents the finalization master.
8421 if Needs_BIP_Finalization_Master (E) then
8424 (E, RTE (RE_Finalization_Master_Ptr),
8425 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8428 -- When the result type contains tasks, add two extra formals: the
8429 -- master of the tasks to be created, and the caller's activation
8432 if Needs_BIP_Task_Actuals (E) then
8435 (E, RTE (RE_Master_Id),
8436 E, BIP_Formal_Suffix (BIP_Task_Master));
8439 (E, RTE (RE_Activation_Chain_Access),
8440 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8443 -- All build-in-place functions get an extra formal that will be
8444 -- passed the address of the return object within the caller.
8447 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8449 -- Incomplete_View_From_Limited_With is needed here because
8450 -- gigi gets confused if the designated type is the full view
8451 -- coming from a limited-with'ed package. In the normal case,
8452 -- (no limited with) Incomplete_View_From_Limited_With
8453 -- returns Result_Subt.
8455 Set_Directly_Designated_Type
8456 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8457 Set_Etype (Formal_Typ, Formal_Typ);
8458 Set_Depends_On_Private
8459 (Formal_Typ, Has_Private_Component (Formal_Typ));
8460 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8461 Set_Is_Access_Constant (Formal_Typ, False);
8463 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8464 -- the designated type comes from the limited view (for back-end
8467 Set_From_Limited_With
8468 (Formal_Typ, From_Limited_With (Result_Subt));
8470 Layout_Type (Formal_Typ);
8472 -- Force the definition of the Itype in case of internal function
8473 -- calls within the same or nested scope.
8475 if Is_Subprogram_Or_Generic_Subprogram (E) then
8476 Subp_Decl := Parent (E);
8478 -- The insertion point for an Itype reference should be after
8479 -- the unit declaration node of the subprogram. An exception
8480 -- to this are inherited operations from a parent type in which
8481 -- case the derived type acts as their parent.
8483 if Nkind_In (Subp_Decl, N_Function_Specification,
8484 N_Procedure_Specification)
8486 Subp_Decl := Parent (Subp_Decl);
8489 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8494 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8498 -- If this is an instance of a generic, we need to have extra formals
8501 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8502 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8504 end Create_Extra_Formals;
8506 -----------------------------
8507 -- Enter_Overloaded_Entity --
8508 -----------------------------
8510 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8511 function Matches_Predefined_Op return Boolean;
8512 -- This returns an approximation of whether S matches a predefined
8513 -- operator, based on the operator symbol, and the parameter and result
8514 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8516 ---------------------------
8517 -- Matches_Predefined_Op --
8518 ---------------------------
8520 function Matches_Predefined_Op return Boolean is
8521 Formal_1 : constant Entity_Id := First_Formal (S);
8522 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8523 Op : constant Name_Id := Chars (S);
8524 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8525 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8530 if Present (Formal_2) then
8532 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8535 -- All but "&" and "**" have same-types parameters
8544 if Type_1 /= Type_2 then
8549 -- Check parameter and result types
8557 Is_Boolean_Type (Result_Type)
8558 and then Result_Type = Type_1;
8564 Is_Integer_Type (Result_Type)
8565 and then Result_Type = Type_1;
8573 Is_Numeric_Type (Result_Type)
8574 and then Result_Type = Type_1;
8580 Is_Boolean_Type (Result_Type)
8581 and then not Is_Limited_Type (Type_1);
8589 Is_Boolean_Type (Result_Type)
8590 and then (Is_Array_Type (Type_1)
8591 or else Is_Scalar_Type (Type_1));
8593 when Name_Op_Concat =>
8594 return Is_Array_Type (Result_Type);
8596 when Name_Op_Expon =>
8598 (Is_Integer_Type (Result_Type)
8599 or else Is_Floating_Point_Type (Result_Type))
8600 and then Result_Type = Type_1
8601 and then Type_2 = Standard_Integer;
8604 raise Program_Error;
8617 Is_Numeric_Type (Result_Type)
8618 and then Result_Type = Type_1;
8622 Is_Boolean_Type (Result_Type)
8623 and then Result_Type = Type_1;
8626 raise Program_Error;
8629 end Matches_Predefined_Op;
8633 E : Entity_Id := Current_Entity_In_Scope (S);
8634 C_E : Entity_Id := Current_Entity (S);
8636 -- Start of processing for Enter_Overloaded_Entity
8640 Set_Has_Homonym (E);
8641 Set_Has_Homonym (S);
8644 Set_Is_Immediately_Visible (S);
8645 Set_Scope (S, Current_Scope);
8647 -- Chain new entity if front of homonym in current scope, so that
8648 -- homonyms are contiguous.
8650 if Present (E) and then E /= C_E then
8651 while Homonym (C_E) /= E loop
8652 C_E := Homonym (C_E);
8655 Set_Homonym (C_E, S);
8659 Set_Current_Entity (S);
8664 if Is_Inherited_Operation (S) then
8665 Append_Inherited_Subprogram (S);
8667 Append_Entity (S, Current_Scope);
8670 Set_Public_Status (S);
8672 if Debug_Flag_E then
8673 Write_Str ("New overloaded entity chain: ");
8674 Write_Name (Chars (S));
8677 while Present (E) loop
8678 Write_Str (" "); Write_Int (Int (E));
8685 -- Generate warning for hiding
8688 and then Comes_From_Source (S)
8689 and then In_Extended_Main_Source_Unit (S)
8696 -- Warn unless genuine overloading. Do not emit warning on
8697 -- hiding predefined operators in Standard (these are either an
8698 -- (artifact of our implicit declarations, or simple noise) but
8699 -- keep warning on a operator defined on a local subtype, because
8700 -- of the real danger that different operators may be applied in
8701 -- various parts of the program.
8703 -- Note that if E and S have the same scope, there is never any
8704 -- hiding. Either the two conflict, and the program is illegal,
8705 -- or S is overriding an implicit inherited subprogram.
8707 if Scope (E) /= Scope (S)
8708 and then (not Is_Overloadable (E)
8709 or else Subtype_Conformant (E, S))
8710 and then (Is_Immediately_Visible (E)
8711 or else Is_Potentially_Use_Visible (S))
8713 if Scope (E) = Standard_Standard then
8714 if Nkind (S) = N_Defining_Operator_Symbol
8715 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8717 and then Matches_Predefined_Op
8720 ("declaration of & hides predefined operator?h?", S);
8723 -- E not immediately within Standard
8726 Error_Msg_Sloc := Sloc (E);
8727 Error_Msg_N ("declaration of & hides one #?h?", S);
8732 end Enter_Overloaded_Entity;
8734 -----------------------------
8735 -- Check_Untagged_Equality --
8736 -----------------------------
8738 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8739 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8740 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8744 -- This check applies only if we have a subprogram declaration with an
8745 -- untagged record type that is conformant to the predefined op.
8747 if Nkind (Decl) /= N_Subprogram_Declaration
8748 or else not Is_Record_Type (Typ)
8749 or else Is_Tagged_Type (Typ)
8750 or else Etype (Next_Formal (First_Formal (Eq_Op))) /= Typ
8755 -- In Ada 2012 case, we will output errors or warnings depending on
8756 -- the setting of debug flag -gnatd.E.
8758 if Ada_Version >= Ada_2012 then
8759 Error_Msg_Warn := Debug_Flag_Dot_EE;
8761 -- In earlier versions of Ada, nothing to do unless we are warning on
8762 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8765 if not Warn_On_Ada_2012_Compatibility then
8770 -- Cases where the type has already been frozen
8772 if Is_Frozen (Typ) then
8774 -- The check applies to a primitive operation, so check that type
8775 -- and equality operation are in the same scope.
8777 if Scope (Typ) /= Current_Scope then
8780 -- If the type is a generic actual (sub)type, the operation is not
8781 -- primitive either because the base type is declared elsewhere.
8783 elsif Is_Generic_Actual_Type (Typ) then
8786 -- Here we have a definite error of declaration after freezing
8789 if Ada_Version >= Ada_2012 then
8791 ("equality operator must be declared before type & is "
8792 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8794 -- In Ada 2012 mode with error turned to warning, output one
8795 -- more warning to warn that the equality operation may not
8796 -- compose. This is the consequence of ignoring the error.
8798 if Error_Msg_Warn then
8799 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8804 ("equality operator must be declared before type& is "
8805 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8808 -- If we are in the package body, we could just move the
8809 -- declaration to the package spec, so add a message saying that.
8811 if In_Package_Body (Scope (Typ)) then
8812 if Ada_Version >= Ada_2012 then
8814 ("\move declaration to package spec<<", Eq_Op);
8817 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8820 -- Otherwise try to find the freezing point for better message.
8823 Obj_Decl := Next (Parent (Typ));
8824 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8825 if Nkind (Obj_Decl) = N_Object_Declaration
8826 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8828 -- Freezing point, output warnings
8830 if Ada_Version >= Ada_2012 then
8832 ("type& is frozen by declaration??", Obj_Decl, Typ);
8834 ("\an equality operator cannot be declared after "
8839 ("type& is frozen by declaration (Ada 2012)?y?",
8842 ("\an equality operator cannot be declared after "
8843 & "this point (Ada 2012)?y?",
8849 -- If we reach generated code for subprogram declaration
8850 -- or body, it is the body that froze the type and the
8851 -- declaration is legal.
8853 elsif Sloc (Obj_Decl) = Sloc (Decl) then
8862 -- Here if type is not frozen yet. It is illegal to have a primitive
8863 -- equality declared in the private part if the type is visible.
8865 elsif not In_Same_List (Parent (Typ), Decl)
8866 and then not Is_Limited_Type (Typ)
8868 -- Shouldn't we give an RM reference here???
8870 if Ada_Version >= Ada_2012 then
8872 ("equality operator appears too late<<", Eq_Op);
8875 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8878 -- No error detected
8883 end Check_Untagged_Equality;
8885 -----------------------------
8886 -- Find_Corresponding_Spec --
8887 -----------------------------
8889 function Find_Corresponding_Spec
8891 Post_Error : Boolean := True) return Entity_Id
8893 Spec : constant Node_Id := Specification (N);
8894 Designator : constant Entity_Id := Defining_Entity (Spec);
8898 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8899 -- Even if fully conformant, a body may depend on a generic actual when
8900 -- the spec does not, or vice versa, in which case they were distinct
8901 -- entities in the generic.
8903 -------------------------------
8904 -- Different_Generic_Profile --
8905 -------------------------------
8907 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8910 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8911 -- Check that the types of corresponding formals have the same
8912 -- generic actual if any. We have to account for subtypes of a
8913 -- generic formal, declared between a spec and a body, which may
8914 -- appear distinct in an instance but matched in the generic, and
8915 -- the subtype may be used either in the spec or the body of the
8916 -- subprogram being checked.
8918 -------------------------
8919 -- Same_Generic_Actual --
8920 -------------------------
8922 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8924 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8925 -- Predicate to check whether S1 is a subtype of S2 in the source
8928 -------------------------
8929 -- Is_Declared_Subtype --
8930 -------------------------
8932 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8934 return Comes_From_Source (Parent (S1))
8935 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8936 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8937 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8938 end Is_Declared_Subtype;
8940 -- Start of processing for Same_Generic_Actual
8943 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8944 or else Is_Declared_Subtype (T1, T2)
8945 or else Is_Declared_Subtype (T2, T1);
8946 end Same_Generic_Actual;
8948 -- Start of processing for Different_Generic_Profile
8951 if not In_Instance then
8954 elsif Ekind (E) = E_Function
8955 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8960 F1 := First_Formal (Designator);
8961 F2 := First_Formal (E);
8962 while Present (F1) loop
8963 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8972 end Different_Generic_Profile;
8974 -- Start of processing for Find_Corresponding_Spec
8977 E := Current_Entity (Designator);
8978 while Present (E) loop
8980 -- We are looking for a matching spec. It must have the same scope,
8981 -- and the same name, and either be type conformant, or be the case
8982 -- of a library procedure spec and its body (which belong to one
8983 -- another regardless of whether they are type conformant or not).
8985 if Scope (E) = Current_Scope then
8986 if Current_Scope = Standard_Standard
8987 or else (Ekind (E) = Ekind (Designator)
8988 and then Type_Conformant (E, Designator))
8990 -- Within an instantiation, we know that spec and body are
8991 -- subtype conformant, because they were subtype conformant in
8992 -- the generic. We choose the subtype-conformant entity here as
8993 -- well, to resolve spurious ambiguities in the instance that
8994 -- were not present in the generic (i.e. when two different
8995 -- types are given the same actual). If we are looking for a
8996 -- spec to match a body, full conformance is expected.
9000 -- Inherit the convention and "ghostness" of the matching
9001 -- spec to ensure proper full and subtype conformance.
9003 Set_Convention (Designator, Convention (E));
9005 -- Skip past subprogram bodies and subprogram renamings that
9006 -- may appear to have a matching spec, but that aren't fully
9007 -- conformant with it. That can occur in cases where an
9008 -- actual type causes unrelated homographs in the instance.
9010 if Nkind_In (N, N_Subprogram_Body,
9011 N_Subprogram_Renaming_Declaration)
9012 and then Present (Homonym (E))
9013 and then not Fully_Conformant (Designator, E)
9017 elsif not Subtype_Conformant (Designator, E) then
9020 elsif Different_Generic_Profile (E) then
9025 -- Ada 2012 (AI05-0165): For internally generated bodies of
9026 -- null procedures locate the internally generated spec. We
9027 -- enforce mode conformance since a tagged type may inherit
9028 -- from interfaces several null primitives which differ only
9029 -- in the mode of the formals.
9031 if not (Comes_From_Source (E))
9032 and then Is_Null_Procedure (E)
9033 and then not Mode_Conformant (Designator, E)
9037 -- For null procedures coming from source that are completions,
9038 -- analysis of the generated body will establish the link.
9040 elsif Comes_From_Source (E)
9041 and then Nkind (Spec) = N_Procedure_Specification
9042 and then Null_Present (Spec)
9046 -- Expression functions can be completions, but cannot be
9047 -- completed by an explicit body.
9049 elsif Comes_From_Source (E)
9050 and then Comes_From_Source (N)
9051 and then Nkind (N) = N_Subprogram_Body
9052 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
9053 N_Expression_Function
9055 Error_Msg_Sloc := Sloc (E);
9056 Error_Msg_N ("body conflicts with expression function#", N);
9059 elsif not Has_Completion (E) then
9060 if Nkind (N) /= N_Subprogram_Body_Stub then
9061 Set_Corresponding_Spec (N, E);
9064 Set_Has_Completion (E);
9067 elsif Nkind (Parent (N)) = N_Subunit then
9069 -- If this is the proper body of a subunit, the completion
9070 -- flag is set when analyzing the stub.
9074 -- If E is an internal function with a controlling result that
9075 -- was created for an operation inherited by a null extension,
9076 -- it may be overridden by a body without a previous spec (one
9077 -- more reason why these should be shunned). In that case we
9078 -- remove the generated body if present, because the current
9079 -- one is the explicit overriding.
9081 elsif Ekind (E) = E_Function
9082 and then Ada_Version >= Ada_2005
9083 and then not Comes_From_Source (E)
9084 and then Has_Controlling_Result (E)
9085 and then Is_Null_Extension (Etype (E))
9086 and then Comes_From_Source (Spec)
9088 Set_Has_Completion (E, False);
9091 and then Nkind (Parent (E)) = N_Function_Specification
9094 (Unit_Declaration_Node
9095 (Corresponding_Body (Unit_Declaration_Node (E))));
9099 -- If expansion is disabled, or if the wrapper function has
9100 -- not been generated yet, this a late body overriding an
9101 -- inherited operation, or it is an overriding by some other
9102 -- declaration before the controlling result is frozen. In
9103 -- either case this is a declaration of a new entity.
9109 -- If the body already exists, then this is an error unless
9110 -- the previous declaration is the implicit declaration of a
9111 -- derived subprogram. It is also legal for an instance to
9112 -- contain type conformant overloadable declarations (but the
9113 -- generic declaration may not), per 8.3(26/2).
9115 elsif No (Alias (E))
9116 and then not Is_Intrinsic_Subprogram (E)
9117 and then not In_Instance
9120 Error_Msg_Sloc := Sloc (E);
9122 if Is_Imported (E) then
9124 ("body not allowed for imported subprogram & declared#",
9127 Error_Msg_NE ("duplicate body for & declared#", N, E);
9131 -- Child units cannot be overloaded, so a conformance mismatch
9132 -- between body and a previous spec is an error.
9134 elsif Is_Child_Unit (E)
9136 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
9138 Nkind (Parent (Unit_Declaration_Node (Designator))) =
9143 ("body of child unit does not match previous declaration", N);
9151 -- On exit, we know that no previous declaration of subprogram exists
9154 end Find_Corresponding_Spec;
9156 ----------------------
9157 -- Fully_Conformant --
9158 ----------------------
9160 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9163 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
9165 end Fully_Conformant;
9167 ----------------------------------
9168 -- Fully_Conformant_Expressions --
9169 ----------------------------------
9171 function Fully_Conformant_Expressions
9172 (Given_E1 : Node_Id;
9174 Report : Boolean := False) return Boolean
9176 E1 : constant Node_Id := Original_Node (Given_E1);
9177 E2 : constant Node_Id := Original_Node (Given_E2);
9178 -- We always test conformance on original nodes, since it is possible
9179 -- for analysis and/or expansion to make things look as though they
9180 -- conform when they do not, e.g. by converting 1+2 into 3.
9182 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean;
9185 function FCL (L1 : List_Id; L2 : List_Id) return Boolean;
9186 -- Compare elements of two lists for conformance. Elements have to be
9187 -- conformant, and actuals inserted as default parameters do not match
9188 -- explicit actuals with the same value.
9190 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean;
9191 -- Compare an operator node with a function call
9197 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean is
9199 return Fully_Conformant_Expressions (Given_E1, Given_E2, Report);
9206 function FCL (L1 : List_Id; L2 : List_Id) return Boolean is
9211 if L1 = No_List then
9217 if L2 = No_List then
9223 -- Compare two lists, skipping rewrite insertions (we want to compare
9224 -- the original trees, not the expanded versions).
9227 if Is_Rewrite_Insertion (N1) then
9229 elsif Is_Rewrite_Insertion (N2) then
9235 elsif not FCE (N1, N2) then
9248 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean is
9249 Actuals : constant List_Id := Parameter_Associations (Call_Node);
9254 or else Entity (Op_Node) /= Entity (Name (Call_Node))
9259 Act := First (Actuals);
9261 if Nkind (Op_Node) in N_Binary_Op then
9262 if not FCE (Left_Opnd (Op_Node), Act) then
9269 return Present (Act)
9270 and then FCE (Right_Opnd (Op_Node), Act)
9271 and then No (Next (Act));
9279 -- Start of processing for Fully_Conformant_Expressions
9284 -- Nonconformant if paren count does not match. Note: if some idiot
9285 -- complains that we don't do this right for more than 3 levels of
9286 -- parentheses, they will be treated with the respect they deserve.
9288 if Paren_Count (E1) /= Paren_Count (E2) then
9291 -- If same entities are referenced, then they are conformant even if
9292 -- they have different forms (RM 8.3.1(19-20)).
9294 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
9295 if Present (Entity (E1)) then
9296 Result := Entity (E1) = Entity (E2)
9298 -- One may be a discriminant that has been replaced by the
9299 -- corresponding discriminal.
9302 (Chars (Entity (E1)) = Chars (Entity (E2))
9303 and then Ekind (Entity (E1)) = E_Discriminant
9304 and then Ekind (Entity (E2)) = E_In_Parameter)
9306 -- The discriminant of a protected type is transformed into
9307 -- a local constant and then into a parameter of a protected
9311 (Ekind (Entity (E1)) = E_Constant
9312 and then Ekind (Entity (E2)) = E_In_Parameter
9313 and then Present (Discriminal_Link (Entity (E1)))
9314 and then Discriminal_Link (Entity (E1)) =
9315 Discriminal_Link (Entity (E2)))
9317 -- AI12-050: The loop variables of quantified expressions match
9318 -- if they have the same identifier, even though they may have
9319 -- different entities.
9322 (Chars (Entity (E1)) = Chars (Entity (E2))
9323 and then Ekind (Entity (E1)) = E_Loop_Parameter
9324 and then Ekind (Entity (E2)) = E_Loop_Parameter)
9326 -- A call to an instantiation of Unchecked_Conversion is
9327 -- rewritten with the name of the generated function created for
9328 -- the instance, and this must be special-cased.
9331 (Ekind (Entity (E1)) = E_Function
9332 and then Is_Intrinsic_Subprogram (Entity (E1))
9333 and then Is_Generic_Instance (Entity (E1))
9334 and then Entity (E2) = Alias (Entity (E1)));
9335 if Report and not Result then
9337 Text_Ptr'Max (Sloc (Entity (E1)), Sloc (Entity (E2)));
9339 ("Meaning of& differs because of declaration#", E1, E2);
9344 elsif Nkind (E1) = N_Expanded_Name
9345 and then Nkind (E2) = N_Expanded_Name
9346 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9347 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9349 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9352 -- Identifiers in component associations don't always have
9353 -- entities, but their names must conform.
9355 return Nkind (E1) = N_Identifier
9356 and then Nkind (E2) = N_Identifier
9357 and then Chars (E1) = Chars (E2);
9360 elsif Nkind (E1) = N_Character_Literal
9361 and then Nkind (E2) = N_Expanded_Name
9363 return Nkind (Selector_Name (E2)) = N_Character_Literal
9364 and then Chars (E1) = Chars (Selector_Name (E2));
9366 elsif Nkind (E2) = N_Character_Literal
9367 and then Nkind (E1) = N_Expanded_Name
9369 return Nkind (Selector_Name (E1)) = N_Character_Literal
9370 and then Chars (E2) = Chars (Selector_Name (E1));
9372 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9373 return FCO (E1, E2);
9375 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9376 return FCO (E2, E1);
9378 -- Otherwise we must have the same syntactic entity
9380 elsif Nkind (E1) /= Nkind (E2) then
9383 -- At this point, we specialize by node type
9389 FCL (Expressions (E1), Expressions (E2))
9391 FCL (Component_Associations (E1),
9392 Component_Associations (E2));
9395 if Nkind (Expression (E1)) = N_Qualified_Expression
9397 Nkind (Expression (E2)) = N_Qualified_Expression
9399 return FCE (Expression (E1), Expression (E2));
9401 -- Check that the subtype marks and any constraints
9406 Indic1 : constant Node_Id := Expression (E1);
9407 Indic2 : constant Node_Id := Expression (E2);
9412 if Nkind (Indic1) /= N_Subtype_Indication then
9414 Nkind (Indic2) /= N_Subtype_Indication
9415 and then Entity (Indic1) = Entity (Indic2);
9417 elsif Nkind (Indic2) /= N_Subtype_Indication then
9419 Nkind (Indic1) /= N_Subtype_Indication
9420 and then Entity (Indic1) = Entity (Indic2);
9423 if Entity (Subtype_Mark (Indic1)) /=
9424 Entity (Subtype_Mark (Indic2))
9429 Elt1 := First (Constraints (Constraint (Indic1)));
9430 Elt2 := First (Constraints (Constraint (Indic2)));
9431 while Present (Elt1) and then Present (Elt2) loop
9432 if not FCE (Elt1, Elt2) then
9445 when N_Attribute_Reference =>
9447 Attribute_Name (E1) = Attribute_Name (E2)
9448 and then FCL (Expressions (E1), Expressions (E2));
9452 Entity (E1) = Entity (E2)
9453 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9454 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9456 when N_Membership_Test
9460 FCE (Left_Opnd (E1), Left_Opnd (E2))
9462 FCE (Right_Opnd (E1), Right_Opnd (E2));
9464 when N_Case_Expression =>
9470 if not FCE (Expression (E1), Expression (E2)) then
9474 Alt1 := First (Alternatives (E1));
9475 Alt2 := First (Alternatives (E2));
9477 if Present (Alt1) /= Present (Alt2) then
9479 elsif No (Alt1) then
9483 if not FCE (Expression (Alt1), Expression (Alt2))
9484 or else not FCL (Discrete_Choices (Alt1),
9485 Discrete_Choices (Alt2))
9496 when N_Character_Literal =>
9498 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9500 when N_Component_Association =>
9502 FCL (Choices (E1), Choices (E2))
9504 FCE (Expression (E1), Expression (E2));
9506 when N_Explicit_Dereference =>
9508 FCE (Prefix (E1), Prefix (E2));
9510 when N_Extension_Aggregate =>
9512 FCL (Expressions (E1), Expressions (E2))
9513 and then Null_Record_Present (E1) =
9514 Null_Record_Present (E2)
9515 and then FCL (Component_Associations (E1),
9516 Component_Associations (E2));
9518 when N_Function_Call =>
9520 FCE (Name (E1), Name (E2))
9522 FCL (Parameter_Associations (E1),
9523 Parameter_Associations (E2));
9525 when N_If_Expression =>
9527 FCL (Expressions (E1), Expressions (E2));
9529 when N_Indexed_Component =>
9531 FCE (Prefix (E1), Prefix (E2))
9533 FCL (Expressions (E1), Expressions (E2));
9535 when N_Integer_Literal =>
9536 return (Intval (E1) = Intval (E2));
9541 when N_Operator_Symbol =>
9543 Chars (E1) = Chars (E2);
9545 when N_Others_Choice =>
9548 when N_Parameter_Association =>
9550 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9551 and then FCE (Explicit_Actual_Parameter (E1),
9552 Explicit_Actual_Parameter (E2));
9554 when N_Qualified_Expression
9556 | N_Unchecked_Type_Conversion
9559 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9561 FCE (Expression (E1), Expression (E2));
9563 when N_Quantified_Expression =>
9564 if not FCE (Condition (E1), Condition (E2)) then
9568 if Present (Loop_Parameter_Specification (E1))
9569 and then Present (Loop_Parameter_Specification (E2))
9572 L1 : constant Node_Id :=
9573 Loop_Parameter_Specification (E1);
9574 L2 : constant Node_Id :=
9575 Loop_Parameter_Specification (E2);
9579 Reverse_Present (L1) = Reverse_Present (L2)
9581 FCE (Defining_Identifier (L1),
9582 Defining_Identifier (L2))
9584 FCE (Discrete_Subtype_Definition (L1),
9585 Discrete_Subtype_Definition (L2));
9588 elsif Present (Iterator_Specification (E1))
9589 and then Present (Iterator_Specification (E2))
9592 I1 : constant Node_Id := Iterator_Specification (E1);
9593 I2 : constant Node_Id := Iterator_Specification (E2);
9597 FCE (Defining_Identifier (I1),
9598 Defining_Identifier (I2))
9600 Of_Present (I1) = Of_Present (I2)
9602 Reverse_Present (I1) = Reverse_Present (I2)
9603 and then FCE (Name (I1), Name (I2))
9604 and then FCE (Subtype_Indication (I1),
9605 Subtype_Indication (I2));
9608 -- The quantified expressions used different specifications to
9609 -- walk their respective ranges.
9617 FCE (Low_Bound (E1), Low_Bound (E2))
9619 FCE (High_Bound (E1), High_Bound (E2));
9621 when N_Real_Literal =>
9622 return (Realval (E1) = Realval (E2));
9624 when N_Selected_Component =>
9626 FCE (Prefix (E1), Prefix (E2))
9628 FCE (Selector_Name (E1), Selector_Name (E2));
9632 FCE (Prefix (E1), Prefix (E2))
9634 FCE (Discrete_Range (E1), Discrete_Range (E2));
9636 when N_String_Literal =>
9638 S1 : constant String_Id := Strval (E1);
9639 S2 : constant String_Id := Strval (E2);
9640 L1 : constant Nat := String_Length (S1);
9641 L2 : constant Nat := String_Length (S2);
9648 for J in 1 .. L1 loop
9649 if Get_String_Char (S1, J) /=
9650 Get_String_Char (S2, J)
9662 Entity (E1) = Entity (E2)
9664 FCE (Right_Opnd (E1), Right_Opnd (E2));
9666 -- All other node types cannot appear in this context. Strictly
9667 -- we should raise a fatal internal error. Instead we just ignore
9668 -- the nodes. This means that if anyone makes a mistake in the
9669 -- expander and mucks an expression tree irretrievably, the result
9670 -- will be a failure to detect a (probably very obscure) case
9671 -- of non-conformance, which is better than bombing on some
9672 -- case where two expressions do in fact conform.
9678 end Fully_Conformant_Expressions;
9680 ----------------------------------------
9681 -- Fully_Conformant_Discrete_Subtypes --
9682 ----------------------------------------
9684 function Fully_Conformant_Discrete_Subtypes
9685 (Given_S1 : Node_Id;
9686 Given_S2 : Node_Id) return Boolean
9688 S1 : constant Node_Id := Original_Node (Given_S1);
9689 S2 : constant Node_Id := Original_Node (Given_S2);
9691 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9692 -- Special-case for a bound given by a discriminant, which in the body
9693 -- is replaced with the discriminal of the enclosing type.
9695 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9696 -- Check both bounds
9698 -----------------------
9699 -- Conforming_Bounds --
9700 -----------------------
9702 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9704 if Is_Entity_Name (B1)
9705 and then Is_Entity_Name (B2)
9706 and then Ekind (Entity (B1)) = E_Discriminant
9708 return Chars (B1) = Chars (B2);
9711 return Fully_Conformant_Expressions (B1, B2);
9713 end Conforming_Bounds;
9715 -----------------------
9716 -- Conforming_Ranges --
9717 -----------------------
9719 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9722 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9724 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9725 end Conforming_Ranges;
9727 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9730 if Nkind (S1) /= Nkind (S2) then
9733 elsif Is_Entity_Name (S1) then
9734 return Entity (S1) = Entity (S2);
9736 elsif Nkind (S1) = N_Range then
9737 return Conforming_Ranges (S1, S2);
9739 elsif Nkind (S1) = N_Subtype_Indication then
9741 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9744 (Range_Expression (Constraint (S1)),
9745 Range_Expression (Constraint (S2)));
9749 end Fully_Conformant_Discrete_Subtypes;
9751 --------------------
9752 -- Install_Entity --
9753 --------------------
9755 procedure Install_Entity (E : Entity_Id) is
9756 Prev : constant Entity_Id := Current_Entity (E);
9758 Set_Is_Immediately_Visible (E);
9759 Set_Current_Entity (E);
9760 Set_Homonym (E, Prev);
9763 ---------------------
9764 -- Install_Formals --
9765 ---------------------
9767 procedure Install_Formals (Id : Entity_Id) is
9770 F := First_Formal (Id);
9771 while Present (F) loop
9775 end Install_Formals;
9777 -----------------------------
9778 -- Is_Interface_Conformant --
9779 -----------------------------
9781 function Is_Interface_Conformant
9782 (Tagged_Type : Entity_Id;
9783 Iface_Prim : Entity_Id;
9784 Prim : Entity_Id) return Boolean
9786 -- The operation may in fact be an inherited (implicit) operation
9787 -- rather than the original interface primitive, so retrieve the
9788 -- ultimate ancestor.
9790 Iface : constant Entity_Id :=
9791 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9792 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9794 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9795 -- Return the controlling formal of Prim
9797 ------------------------
9798 -- Controlling_Formal --
9799 ------------------------
9801 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9805 E := First_Entity (Prim);
9806 while Present (E) loop
9807 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9815 end Controlling_Formal;
9819 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9820 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9822 -- Start of processing for Is_Interface_Conformant
9825 pragma Assert (Is_Subprogram (Iface_Prim)
9826 and then Is_Subprogram (Prim)
9827 and then Is_Dispatching_Operation (Iface_Prim)
9828 and then Is_Dispatching_Operation (Prim));
9830 pragma Assert (Is_Interface (Iface)
9831 or else (Present (Alias (Iface_Prim))
9834 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9836 if Prim = Iface_Prim
9837 or else not Is_Subprogram (Prim)
9838 or else Ekind (Prim) /= Ekind (Iface_Prim)
9839 or else not Is_Dispatching_Operation (Prim)
9840 or else Scope (Prim) /= Scope (Tagged_Type)
9842 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9843 or else not Primitive_Names_Match (Iface_Prim, Prim)
9847 -- The mode of the controlling formals must match
9849 elsif Present (Iface_Ctrl_F)
9850 and then Present (Prim_Ctrl_F)
9851 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9855 -- Case of a procedure, or a function whose result type matches the
9856 -- result type of the interface primitive, or a function that has no
9857 -- controlling result (I or access I).
9859 elsif Ekind (Iface_Prim) = E_Procedure
9860 or else Etype (Prim) = Etype (Iface_Prim)
9861 or else not Has_Controlling_Result (Prim)
9863 return Type_Conformant
9864 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9866 -- Case of a function returning an interface, or an access to one. Check
9867 -- that the return types correspond.
9869 elsif Implements_Interface (Typ, Iface) then
9870 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9872 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9877 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9878 Skip_Controlling_Formals => True);
9884 end Is_Interface_Conformant;
9886 ---------------------------------
9887 -- Is_Non_Overriding_Operation --
9888 ---------------------------------
9890 function Is_Non_Overriding_Operation
9891 (Prev_E : Entity_Id;
9892 New_E : Entity_Id) return Boolean
9896 G_Typ : Entity_Id := Empty;
9898 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9899 -- If F_Type is a derived type associated with a generic actual subtype,
9900 -- then return its Generic_Parent_Type attribute, else return Empty.
9902 function Types_Correspond
9903 (P_Type : Entity_Id;
9904 N_Type : Entity_Id) return Boolean;
9905 -- Returns true if and only if the types (or designated types in the
9906 -- case of anonymous access types) are the same or N_Type is derived
9907 -- directly or indirectly from P_Type.
9909 -----------------------------
9910 -- Get_Generic_Parent_Type --
9911 -----------------------------
9913 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9919 if Is_Derived_Type (F_Typ)
9920 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9922 -- The tree must be traversed to determine the parent subtype in
9923 -- the generic unit, which unfortunately isn't always available
9924 -- via semantic attributes. ??? (Note: The use of Original_Node
9925 -- is needed for cases where a full derived type has been
9928 -- If the parent type is a scalar type, the derivation creates
9929 -- an anonymous base type for it, and the source type is its
9932 if Is_Scalar_Type (F_Typ)
9933 and then not Comes_From_Source (F_Typ)
9937 (Original_Node (Parent (First_Subtype (F_Typ))));
9939 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9941 if Nkind (Defn) = N_Derived_Type_Definition then
9942 Indic := Subtype_Indication (Defn);
9944 if Nkind (Indic) = N_Subtype_Indication then
9945 G_Typ := Entity (Subtype_Mark (Indic));
9947 G_Typ := Entity (Indic);
9950 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9951 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9953 return Generic_Parent_Type (Parent (G_Typ));
9959 end Get_Generic_Parent_Type;
9961 ----------------------
9962 -- Types_Correspond --
9963 ----------------------
9965 function Types_Correspond
9966 (P_Type : Entity_Id;
9967 N_Type : Entity_Id) return Boolean
9969 Prev_Type : Entity_Id := Base_Type (P_Type);
9970 New_Type : Entity_Id := Base_Type (N_Type);
9973 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9974 Prev_Type := Designated_Type (Prev_Type);
9977 if Ekind (New_Type) = E_Anonymous_Access_Type then
9978 New_Type := Designated_Type (New_Type);
9981 if Prev_Type = New_Type then
9984 elsif not Is_Class_Wide_Type (New_Type) then
9985 while Etype (New_Type) /= New_Type loop
9986 New_Type := Etype (New_Type);
9988 if New_Type = Prev_Type then
9994 end Types_Correspond;
9996 -- Start of processing for Is_Non_Overriding_Operation
9999 -- In the case where both operations are implicit derived subprograms
10000 -- then neither overrides the other. This can only occur in certain
10001 -- obscure cases (e.g., derivation from homographs created in a generic
10004 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
10007 elsif Ekind (Current_Scope) = E_Package
10008 and then Is_Generic_Instance (Current_Scope)
10009 and then In_Private_Part (Current_Scope)
10010 and then Comes_From_Source (New_E)
10012 -- We examine the formals and result type of the inherited operation,
10013 -- to determine whether their type is derived from (the instance of)
10014 -- a generic type. The first such formal or result type is the one
10017 Formal := First_Formal (Prev_E);
10019 while Present (Formal) loop
10020 F_Typ := Base_Type (Etype (Formal));
10022 if Ekind (F_Typ) = E_Anonymous_Access_Type then
10023 F_Typ := Designated_Type (F_Typ);
10026 G_Typ := Get_Generic_Parent_Type (F_Typ);
10027 exit when Present (G_Typ);
10029 Next_Formal (Formal);
10032 -- If the function dispatches on result check the result type
10034 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
10035 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
10042 -- If the generic type is a private type, then the original operation
10043 -- was not overriding in the generic, because there was no primitive
10044 -- operation to override.
10046 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
10047 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
10048 N_Formal_Private_Type_Definition
10052 -- The generic parent type is the ancestor of a formal derived
10053 -- type declaration. We need to check whether it has a primitive
10054 -- operation that should be overridden by New_E in the generic.
10058 P_Formal : Entity_Id;
10059 N_Formal : Entity_Id;
10062 P_Prim : Entity_Id;
10063 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
10066 while Present (Prim_Elt) loop
10067 P_Prim := Node (Prim_Elt);
10069 if Chars (P_Prim) = Chars (New_E)
10070 and then Ekind (P_Prim) = Ekind (New_E)
10072 P_Formal := First_Formal (P_Prim);
10073 N_Formal := First_Formal (New_E);
10074 while Present (P_Formal) and then Present (N_Formal) loop
10075 P_Typ := Etype (P_Formal);
10076 N_Typ := Etype (N_Formal);
10078 if not Types_Correspond (P_Typ, N_Typ) then
10082 Next_Entity (P_Formal);
10083 Next_Entity (N_Formal);
10086 -- Found a matching primitive operation belonging to the
10087 -- formal ancestor type, so the new subprogram is
10091 and then No (N_Formal)
10092 and then (Ekind (New_E) /= E_Function
10095 (Etype (P_Prim), Etype (New_E)))
10101 Next_Elmt (Prim_Elt);
10104 -- If no match found, then the new subprogram does not override
10105 -- in the generic (nor in the instance).
10107 -- If the type in question is not abstract, and the subprogram
10108 -- is, this will be an error if the new operation is in the
10109 -- private part of the instance. Emit a warning now, which will
10110 -- make the subsequent error message easier to understand.
10112 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
10113 and then Is_Abstract_Subprogram (Prev_E)
10114 and then In_Private_Part (Current_Scope)
10116 Error_Msg_Node_2 := F_Typ;
10118 ("private operation& in generic unit does not override "
10119 & "any primitive operation of& (RM 12.3 (18))??",
10129 end Is_Non_Overriding_Operation;
10131 -------------------------------------
10132 -- List_Inherited_Pre_Post_Aspects --
10133 -------------------------------------
10135 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
10137 if Opt.List_Inherited_Aspects
10138 and then Is_Subprogram_Or_Generic_Subprogram (E)
10141 Subps : constant Subprogram_List := Inherited_Subprograms (E);
10146 for Index in Subps'Range loop
10147 Items := Contract (Subps (Index));
10149 if Present (Items) then
10150 Prag := Pre_Post_Conditions (Items);
10151 while Present (Prag) loop
10152 Error_Msg_Sloc := Sloc (Prag);
10154 if Class_Present (Prag)
10155 and then not Split_PPC (Prag)
10157 if Pragma_Name (Prag) = Name_Precondition then
10159 ("info: & inherits `Pre''Class` aspect from "
10163 ("info: & inherits `Post''Class` aspect from "
10168 Prag := Next_Pragma (Prag);
10174 end List_Inherited_Pre_Post_Aspects;
10176 ------------------------------
10177 -- Make_Inequality_Operator --
10178 ------------------------------
10180 -- S is the defining identifier of an equality operator. We build a
10181 -- subprogram declaration with the right signature. This operation is
10182 -- intrinsic, because it is always expanded as the negation of the
10183 -- call to the equality function.
10185 procedure Make_Inequality_Operator (S : Entity_Id) is
10186 Loc : constant Source_Ptr := Sloc (S);
10189 Op_Name : Entity_Id;
10191 FF : constant Entity_Id := First_Formal (S);
10192 NF : constant Entity_Id := Next_Formal (FF);
10195 -- Check that equality was properly defined, ignore call if not
10202 A : constant Entity_Id :=
10203 Make_Defining_Identifier (Sloc (FF),
10204 Chars => Chars (FF));
10206 B : constant Entity_Id :=
10207 Make_Defining_Identifier (Sloc (NF),
10208 Chars => Chars (NF));
10211 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
10213 Formals := New_List (
10214 Make_Parameter_Specification (Loc,
10215 Defining_Identifier => A,
10217 New_Occurrence_Of (Etype (First_Formal (S)),
10218 Sloc (Etype (First_Formal (S))))),
10220 Make_Parameter_Specification (Loc,
10221 Defining_Identifier => B,
10223 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
10224 Sloc (Etype (Next_Formal (First_Formal (S)))))));
10227 Make_Subprogram_Declaration (Loc,
10229 Make_Function_Specification (Loc,
10230 Defining_Unit_Name => Op_Name,
10231 Parameter_Specifications => Formals,
10232 Result_Definition =>
10233 New_Occurrence_Of (Standard_Boolean, Loc)));
10235 -- Insert inequality right after equality if it is explicit or after
10236 -- the derived type when implicit. These entities are created only
10237 -- for visibility purposes, and eventually replaced in the course
10238 -- of expansion, so they do not need to be attached to the tree and
10239 -- seen by the back-end. Keeping them internal also avoids spurious
10240 -- freezing problems. The declaration is inserted in the tree for
10241 -- analysis, and removed afterwards. If the equality operator comes
10242 -- from an explicit declaration, attach the inequality immediately
10243 -- after. Else the equality is inherited from a derived type
10244 -- declaration, so insert inequality after that declaration.
10246 if No (Alias (S)) then
10247 Insert_After (Unit_Declaration_Node (S), Decl);
10248 elsif Is_List_Member (Parent (S)) then
10249 Insert_After (Parent (S), Decl);
10251 Insert_After (Parent (Etype (First_Formal (S))), Decl);
10254 Mark_Rewrite_Insertion (Decl);
10255 Set_Is_Intrinsic_Subprogram (Op_Name);
10258 Set_Has_Completion (Op_Name);
10259 Set_Corresponding_Equality (Op_Name, S);
10260 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
10262 end Make_Inequality_Operator;
10264 ----------------------
10265 -- May_Need_Actuals --
10266 ----------------------
10268 procedure May_Need_Actuals (Fun : Entity_Id) is
10273 F := First_Formal (Fun);
10275 while Present (F) loop
10276 if No (Default_Value (F)) then
10284 Set_Needs_No_Actuals (Fun, B);
10285 end May_Need_Actuals;
10287 ---------------------
10288 -- Mode_Conformant --
10289 ---------------------
10291 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
10294 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
10296 end Mode_Conformant;
10298 ---------------------------
10299 -- New_Overloaded_Entity --
10300 ---------------------------
10302 procedure New_Overloaded_Entity
10304 Derived_Type : Entity_Id := Empty)
10306 Overridden_Subp : Entity_Id := Empty;
10307 -- Set if the current scope has an operation that is type-conformant
10308 -- with S, and becomes hidden by S.
10310 Is_Primitive_Subp : Boolean;
10311 -- Set to True if the new subprogram is primitive
10314 -- Entity that S overrides
10316 procedure Check_For_Primitive_Subprogram
10317 (Is_Primitive : out Boolean;
10318 Is_Overriding : Boolean := False);
10319 -- If the subprogram being analyzed is a primitive operation of the type
10320 -- of a formal or result, set the Has_Primitive_Operations flag on the
10321 -- type, and set Is_Primitive to True (otherwise set to False). Set the
10322 -- corresponding flag on the entity itself for later use.
10324 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10325 -- True if a) E is a subprogram whose first formal is a concurrent type
10326 -- defined in the scope of E that has some entry or subprogram whose
10327 -- profile matches E, or b) E is an internally built dispatching
10328 -- subprogram of a protected type and there is a matching subprogram
10329 -- defined in the enclosing scope of the protected type, or c) E is
10330 -- an entry of a synchronized type and a matching procedure has been
10331 -- previously defined in the enclosing scope of the synchronized type.
10333 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10334 -- Check that E is declared in the private part of the current package,
10335 -- or in the package body, where it may hide a previous declaration.
10336 -- We can't use In_Private_Part by itself because this flag is also
10337 -- set when freezing entities, so we must examine the place of the
10338 -- declaration in the tree, and recognize wrapper packages as well.
10340 function Is_Overriding_Alias
10341 (Old_E : Entity_Id;
10342 New_E : Entity_Id) return Boolean;
10343 -- Check whether new subprogram and old subprogram are both inherited
10344 -- from subprograms that have distinct dispatch table entries. This can
10345 -- occur with derivations from instances with accidental homonyms. The
10346 -- function is conservative given that the converse is only true within
10347 -- instances that contain accidental overloadings.
10349 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10350 -- Report conflict between entities S and E
10352 ------------------------------------
10353 -- Check_For_Primitive_Subprogram --
10354 ------------------------------------
10356 procedure Check_For_Primitive_Subprogram
10357 (Is_Primitive : out Boolean;
10358 Is_Overriding : Boolean := False)
10360 Formal : Entity_Id;
10364 function Visible_Part_Type (T : Entity_Id) return Boolean;
10365 -- Returns true if T is declared in the visible part of the current
10366 -- package scope; otherwise returns false. Assumes that T is declared
10369 procedure Check_Private_Overriding (T : Entity_Id);
10370 -- Checks that if a primitive abstract subprogram of a visible
10371 -- abstract type is declared in a private part, then it must override
10372 -- an abstract subprogram declared in the visible part. Also checks
10373 -- that if a primitive function with a controlling result is declared
10374 -- in a private part, then it must override a function declared in
10375 -- the visible part.
10377 ------------------------------
10378 -- Check_Private_Overriding --
10379 ------------------------------
10381 procedure Check_Private_Overriding (T : Entity_Id) is
10382 function Overrides_Private_Part_Op return Boolean;
10383 -- This detects the special case where the overriding subprogram
10384 -- is overriding a subprogram that was declared in the same
10385 -- private part. That case is illegal by 3.9.3(10).
10387 function Overrides_Visible_Function
10388 (Partial_View : Entity_Id) return Boolean;
10389 -- True if S overrides a function in the visible part. The
10390 -- overridden function could be explicitly or implicitly declared.
10392 -------------------------------
10393 -- Overrides_Private_Part_Op --
10394 -------------------------------
10396 function Overrides_Private_Part_Op return Boolean is
10397 Over_Decl : constant Node_Id :=
10398 Unit_Declaration_Node (Overridden_Operation (S));
10399 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10402 pragma Assert (Is_Overriding);
10404 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10406 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10408 return In_Same_List (Over_Decl, Subp_Decl);
10409 end Overrides_Private_Part_Op;
10411 --------------------------------
10412 -- Overrides_Visible_Function --
10413 --------------------------------
10415 function Overrides_Visible_Function
10416 (Partial_View : Entity_Id) return Boolean
10419 if not Is_Overriding or else not Has_Homonym (S) then
10423 if not Present (Partial_View) then
10427 -- Search through all the homonyms H of S in the current
10428 -- package spec, and return True if we find one that matches.
10429 -- Note that Parent (H) will be the declaration of the
10430 -- partial view of T for a match.
10433 H : Entity_Id := S;
10437 exit when not Present (H) or else Scope (H) /= Scope (S);
10441 N_Private_Extension_Declaration,
10442 N_Private_Type_Declaration)
10443 and then Defining_Identifier (Parent (H)) = Partial_View
10451 end Overrides_Visible_Function;
10453 -- Start of processing for Check_Private_Overriding
10456 if Is_Package_Or_Generic_Package (Current_Scope)
10457 and then In_Private_Part (Current_Scope)
10458 and then Visible_Part_Type (T)
10459 and then not In_Instance
10461 if Is_Abstract_Type (T)
10462 and then Is_Abstract_Subprogram (S)
10463 and then (not Is_Overriding
10464 or else not Is_Abstract_Subprogram (E)
10465 or else Overrides_Private_Part_Op)
10468 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10471 elsif Ekind (S) = E_Function then
10473 Partial_View : constant Entity_Id :=
10474 Incomplete_Or_Partial_View (T);
10477 if not Overrides_Visible_Function (Partial_View) then
10479 -- Here, S is "function ... return T;" declared in
10480 -- the private part, not overriding some visible
10481 -- operation. That's illegal in the tagged case
10482 -- (but not if the private type is untagged).
10484 if ((Present (Partial_View)
10485 and then Is_Tagged_Type (Partial_View))
10486 or else (not Present (Partial_View)
10487 and then Is_Tagged_Type (T)))
10488 and then T = Base_Type (Etype (S))
10491 ("private function with tagged result must"
10492 & " override visible-part function", S);
10494 ("\move subprogram to the visible part"
10495 & " (RM 3.9.3(10))", S);
10497 -- AI05-0073: extend this test to the case of a
10498 -- function with a controlling access result.
10500 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10501 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10503 not Is_Class_Wide_Type
10504 (Designated_Type (Etype (S)))
10505 and then Ada_Version >= Ada_2012
10508 ("private function with controlling access "
10509 & "result must override visible-part function",
10512 ("\move subprogram to the visible part"
10513 & " (RM 3.9.3(10))", S);
10519 end Check_Private_Overriding;
10521 -----------------------
10522 -- Visible_Part_Type --
10523 -----------------------
10525 function Visible_Part_Type (T : Entity_Id) return Boolean is
10526 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10529 -- If the entity is a private type, then it must be declared in a
10532 if Ekind (T) in Private_Kind then
10535 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10538 elsif Is_List_Member (Declaration_Node (T))
10539 and then List_Containing (Declaration_Node (T)) =
10540 Visible_Declarations (Specification (P))
10547 end Visible_Part_Type;
10549 -- Start of processing for Check_For_Primitive_Subprogram
10552 Is_Primitive := False;
10554 if not Comes_From_Source (S) then
10557 -- If subprogram is at library level, it is not primitive operation
10559 elsif Current_Scope = Standard_Standard then
10562 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10563 and then not In_Package_Body (Current_Scope))
10564 or else Is_Overriding
10566 -- For function, check return type
10568 if Ekind (S) = E_Function then
10569 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10570 F_Typ := Designated_Type (Etype (S));
10572 F_Typ := Etype (S);
10575 B_Typ := Base_Type (F_Typ);
10577 if Scope (B_Typ) = Current_Scope
10578 and then not Is_Class_Wide_Type (B_Typ)
10579 and then not Is_Generic_Type (B_Typ)
10581 Is_Primitive := True;
10582 Set_Has_Primitive_Operations (B_Typ);
10583 Set_Is_Primitive (S);
10584 Check_Private_Overriding (B_Typ);
10586 -- The Ghost policy in effect at the point of declaration
10587 -- or a tagged type and a primitive operation must match
10588 -- (SPARK RM 6.9(16)).
10590 Check_Ghost_Primitive (S, B_Typ);
10594 -- For all subprograms, check formals
10596 Formal := First_Formal (S);
10597 while Present (Formal) loop
10598 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10599 F_Typ := Designated_Type (Etype (Formal));
10601 F_Typ := Etype (Formal);
10604 B_Typ := Base_Type (F_Typ);
10606 if Ekind (B_Typ) = E_Access_Subtype then
10607 B_Typ := Base_Type (B_Typ);
10610 if Scope (B_Typ) = Current_Scope
10611 and then not Is_Class_Wide_Type (B_Typ)
10612 and then not Is_Generic_Type (B_Typ)
10614 Is_Primitive := True;
10615 Set_Is_Primitive (S);
10616 Set_Has_Primitive_Operations (B_Typ);
10617 Check_Private_Overriding (B_Typ);
10619 -- The Ghost policy in effect at the point of declaration
10620 -- of a tagged type and a primitive operation must match
10621 -- (SPARK RM 6.9(16)).
10623 Check_Ghost_Primitive (S, B_Typ);
10626 Next_Formal (Formal);
10629 -- Special case: An equality function can be redefined for a type
10630 -- occurring in a declarative part, and won't otherwise be treated as
10631 -- a primitive because it doesn't occur in a package spec and doesn't
10632 -- override an inherited subprogram. It's important that we mark it
10633 -- primitive so it can be returned by Collect_Primitive_Operations
10634 -- and be used in composing the equality operation of later types
10635 -- that have a component of the type.
10637 elsif Chars (S) = Name_Op_Eq
10638 and then Etype (S) = Standard_Boolean
10640 B_Typ := Base_Type (Etype (First_Formal (S)));
10642 if Scope (B_Typ) = Current_Scope
10644 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10645 and then not Is_Limited_Type (B_Typ)
10647 Is_Primitive := True;
10648 Set_Is_Primitive (S);
10649 Set_Has_Primitive_Operations (B_Typ);
10650 Check_Private_Overriding (B_Typ);
10652 -- The Ghost policy in effect at the point of declaration of a
10653 -- tagged type and a primitive operation must match
10654 -- (SPARK RM 6.9(16)).
10656 Check_Ghost_Primitive (S, B_Typ);
10659 end Check_For_Primitive_Subprogram;
10661 --------------------------------------
10662 -- Has_Matching_Entry_Or_Subprogram --
10663 --------------------------------------
10665 function Has_Matching_Entry_Or_Subprogram
10666 (E : Entity_Id) return Boolean
10668 function Check_Conforming_Parameters
10669 (E1_Param : Node_Id;
10670 E2_Param : Node_Id;
10671 Ctype : Conformance_Type) return Boolean;
10672 -- Starting from the given parameters, check that all the parameters
10673 -- of two entries or subprograms are conformant. Used to skip
10674 -- the check on the controlling argument.
10676 function Matching_Entry_Or_Subprogram
10677 (Conc_Typ : Entity_Id;
10678 Subp : Entity_Id) return Entity_Id;
10679 -- Return the first entry or subprogram of the given concurrent type
10680 -- whose name matches the name of Subp and has a profile conformant
10681 -- with Subp; return Empty if not found.
10683 function Matching_Dispatching_Subprogram
10684 (Conc_Typ : Entity_Id;
10685 Ent : Entity_Id) return Entity_Id;
10686 -- Return the first dispatching primitive of Conc_Type defined in the
10687 -- enclosing scope of Conc_Type (i.e. before the full definition of
10688 -- this concurrent type) whose name matches the entry Ent and has a
10689 -- profile conformant with the profile of the corresponding (not yet
10690 -- built) dispatching primitive of Ent; return Empty if not found.
10692 function Matching_Original_Protected_Subprogram
10693 (Prot_Typ : Entity_Id;
10694 Subp : Entity_Id) return Entity_Id;
10695 -- Return the first subprogram defined in the enclosing scope of
10696 -- Prot_Typ (before the full definition of this protected type)
10697 -- whose name matches the original name of Subp and has a profile
10698 -- conformant with the profile of Subp; return Empty if not found.
10700 function Normalized_First_Parameter_Type
10701 (E : Entity_Id) return Entity_Id;
10702 -- Return the type of the first parameter unless that type
10703 -- is an anonymous access type, in which case return the
10704 -- designated type. Used to treat anonymous-access-to-synchronized
10705 -- the same as synchronized for purposes of checking for
10706 -- prefixed view profile conflicts.
10708 ---------------------------------
10709 -- Check_Conforming_Parameters --
10710 ---------------------------------
10712 function Check_Conforming_Parameters
10713 (E1_Param : Node_Id;
10714 E2_Param : Node_Id;
10715 Ctype : Conformance_Type) return Boolean
10717 Param_E1 : Node_Id := E1_Param;
10718 Param_E2 : Node_Id := E2_Param;
10721 while Present (Param_E1) and then Present (Param_E2) loop
10722 if (Ctype >= Mode_Conformant) and then
10723 Ekind (Defining_Identifier (Param_E1)) /=
10724 Ekind (Defining_Identifier (Param_E2))
10729 (Find_Parameter_Type (Param_E1),
10730 Find_Parameter_Type (Param_E2),
10740 -- The candidate is not valid if one of the two lists contains
10741 -- more parameters than the other
10743 return No (Param_E1) and then No (Param_E2);
10744 end Check_Conforming_Parameters;
10746 ----------------------------------
10747 -- Matching_Entry_Or_Subprogram --
10748 ----------------------------------
10750 function Matching_Entry_Or_Subprogram
10751 (Conc_Typ : Entity_Id;
10752 Subp : Entity_Id) return Entity_Id
10757 E := First_Entity (Conc_Typ);
10758 while Present (E) loop
10759 if Chars (Subp) = Chars (E)
10760 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10762 Check_Conforming_Parameters
10763 (First (Parameter_Specifications (Parent (E))),
10764 Next (First (Parameter_Specifications (Parent (Subp)))),
10774 end Matching_Entry_Or_Subprogram;
10776 -------------------------------------
10777 -- Matching_Dispatching_Subprogram --
10778 -------------------------------------
10780 function Matching_Dispatching_Subprogram
10781 (Conc_Typ : Entity_Id;
10782 Ent : Entity_Id) return Entity_Id
10787 -- Search for entities in the enclosing scope of this synchonized
10790 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10791 Push_Scope (Scope (Conc_Typ));
10792 E := Current_Entity_In_Scope (Ent);
10795 while Present (E) loop
10796 if Scope (E) = Scope (Conc_Typ)
10797 and then Comes_From_Source (E)
10798 and then Ekind (E) = E_Procedure
10799 and then Present (First_Entity (E))
10800 and then Is_Controlling_Formal (First_Entity (E))
10801 and then Etype (First_Entity (E)) = Conc_Typ
10803 Check_Conforming_Parameters
10804 (First (Parameter_Specifications (Parent (Ent))),
10805 Next (First (Parameter_Specifications (Parent (E)))),
10806 Subtype_Conformant)
10815 end Matching_Dispatching_Subprogram;
10817 --------------------------------------------
10818 -- Matching_Original_Protected_Subprogram --
10819 --------------------------------------------
10821 function Matching_Original_Protected_Subprogram
10822 (Prot_Typ : Entity_Id;
10823 Subp : Entity_Id) return Entity_Id
10825 ICF : constant Boolean :=
10826 Is_Controlling_Formal (First_Entity (Subp));
10830 -- Temporarily decorate the first parameter of Subp as controlling
10831 -- formal, required to invoke Subtype_Conformant.
10833 Set_Is_Controlling_Formal (First_Entity (Subp));
10836 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10838 while Present (E) loop
10839 if Scope (E) = Scope (Prot_Typ)
10840 and then Comes_From_Source (E)
10841 and then Ekind (Subp) = Ekind (E)
10842 and then Present (First_Entity (E))
10843 and then Is_Controlling_Formal (First_Entity (E))
10844 and then Etype (First_Entity (E)) = Prot_Typ
10845 and then Subtype_Conformant (Subp, E,
10846 Skip_Controlling_Formals => True)
10848 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10855 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10858 end Matching_Original_Protected_Subprogram;
10860 -------------------------------------
10861 -- Normalized_First_Parameter_Type --
10862 -------------------------------------
10864 function Normalized_First_Parameter_Type
10865 (E : Entity_Id) return Entity_Id
10867 Result : Entity_Id := Etype (First_Entity (E));
10869 if Ekind (Result) = E_Anonymous_Access_Type then
10870 Result := Designated_Type (Result);
10873 end Normalized_First_Parameter_Type;
10875 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10878 -- Case 1: E is a subprogram whose first formal is a concurrent type
10879 -- defined in the scope of E that has an entry or subprogram whose
10880 -- profile matches E.
10882 if Comes_From_Source (E)
10883 and then Is_Subprogram (E)
10884 and then Present (First_Entity (E))
10885 and then Is_Concurrent_Record_Type
10886 (Normalized_First_Parameter_Type (E))
10889 Scope (Corresponding_Concurrent_Type
10890 (Normalized_First_Parameter_Type (E)))
10893 (Matching_Entry_Or_Subprogram
10894 (Corresponding_Concurrent_Type
10895 (Normalized_First_Parameter_Type (E)),
10898 Report_Conflict (E,
10899 Matching_Entry_Or_Subprogram
10900 (Corresponding_Concurrent_Type
10901 (Normalized_First_Parameter_Type (E)),
10906 -- Case 2: E is an internally built dispatching subprogram of a
10907 -- protected type and there is a subprogram defined in the enclosing
10908 -- scope of the protected type that has the original name of E and
10909 -- its profile is conformant with the profile of E. We check the
10910 -- name of the original protected subprogram associated with E since
10911 -- the expander builds dispatching primitives of protected functions
10912 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10914 elsif not Comes_From_Source (E)
10915 and then Is_Subprogram (E)
10916 and then Present (First_Entity (E))
10917 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10918 and then Present (Original_Protected_Subprogram (E))
10921 (Matching_Original_Protected_Subprogram
10922 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10925 Report_Conflict (E,
10926 Matching_Original_Protected_Subprogram
10927 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10931 -- Case 3: E is an entry of a synchronized type and a matching
10932 -- procedure has been previously defined in the enclosing scope
10933 -- of the synchronized type.
10935 elsif Comes_From_Source (E)
10936 and then Ekind (E) = E_Entry
10938 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10940 Report_Conflict (E,
10941 Matching_Dispatching_Subprogram (Current_Scope, E));
10946 end Has_Matching_Entry_Or_Subprogram;
10948 ----------------------------
10949 -- Is_Private_Declaration --
10950 ----------------------------
10952 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10953 Decl : constant Node_Id := Unit_Declaration_Node (E);
10954 Priv_Decls : List_Id;
10957 if Is_Package_Or_Generic_Package (Current_Scope)
10958 and then In_Private_Part (Current_Scope)
10961 Private_Declarations (Package_Specification (Current_Scope));
10963 return In_Package_Body (Current_Scope)
10965 (Is_List_Member (Decl)
10966 and then List_Containing (Decl) = Priv_Decls)
10967 or else (Nkind (Parent (Decl)) = N_Package_Specification
10969 Is_Compilation_Unit
10970 (Defining_Entity (Parent (Decl)))
10971 and then List_Containing (Parent (Parent (Decl))) =
10976 end Is_Private_Declaration;
10978 --------------------------
10979 -- Is_Overriding_Alias --
10980 --------------------------
10982 function Is_Overriding_Alias
10983 (Old_E : Entity_Id;
10984 New_E : Entity_Id) return Boolean
10986 AO : constant Entity_Id := Alias (Old_E);
10987 AN : constant Entity_Id := Alias (New_E);
10990 return Scope (AO) /= Scope (AN)
10991 or else No (DTC_Entity (AO))
10992 or else No (DTC_Entity (AN))
10993 or else DT_Position (AO) = DT_Position (AN);
10994 end Is_Overriding_Alias;
10996 ---------------------
10997 -- Report_Conflict --
10998 ---------------------
11000 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
11002 Error_Msg_Sloc := Sloc (E);
11004 -- Generate message, with useful additional warning if in generic
11006 if Is_Generic_Unit (E) then
11007 Error_Msg_N ("previous generic unit cannot be overloaded", S);
11008 Error_Msg_N ("\& conflicts with declaration#", S);
11010 Error_Msg_N ("& conflicts with declaration#", S);
11012 end Report_Conflict;
11014 -- Start of processing for New_Overloaded_Entity
11017 -- We need to look for an entity that S may override. This must be a
11018 -- homonym in the current scope, so we look for the first homonym of
11019 -- S in the current scope as the starting point for the search.
11021 E := Current_Entity_In_Scope (S);
11023 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
11024 -- They are directly added to the list of primitive operations of
11025 -- Derived_Type, unless this is a rederivation in the private part
11026 -- of an operation that was already derived in the visible part of
11027 -- the current package.
11029 if Ada_Version >= Ada_2005
11030 and then Present (Derived_Type)
11031 and then Present (Alias (S))
11032 and then Is_Dispatching_Operation (Alias (S))
11033 and then Present (Find_Dispatching_Type (Alias (S)))
11034 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
11036 -- For private types, when the full-view is processed we propagate to
11037 -- the full view the non-overridden entities whose attribute "alias"
11038 -- references an interface primitive. These entities were added by
11039 -- Derive_Subprograms to ensure that interface primitives are
11042 -- Inside_Freeze_Actions is non zero when S corresponds with an
11043 -- internal entity that links an interface primitive with its
11044 -- covering primitive through attribute Interface_Alias (see
11045 -- Add_Internal_Interface_Entities).
11047 if Inside_Freezing_Actions = 0
11048 and then Is_Package_Or_Generic_Package (Current_Scope)
11049 and then In_Private_Part (Current_Scope)
11050 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
11051 and then Nkind (Parent (S)) = N_Full_Type_Declaration
11052 and then Full_View (Defining_Identifier (Parent (E)))
11053 = Defining_Identifier (Parent (S))
11054 and then Alias (E) = Alias (S)
11056 Check_Operation_From_Private_View (S, E);
11057 Set_Is_Dispatching_Operation (S);
11062 Enter_Overloaded_Entity (S);
11063 Check_Dispatching_Operation (S, Empty);
11064 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11070 -- For synchronized types check conflicts of this entity with previously
11071 -- defined entities.
11073 if Ada_Version >= Ada_2005
11074 and then Has_Matching_Entry_Or_Subprogram (S)
11079 -- If there is no homonym then this is definitely not overriding
11082 Enter_Overloaded_Entity (S);
11083 Check_Dispatching_Operation (S, Empty);
11084 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11086 -- If subprogram has an explicit declaration, check whether it has an
11087 -- overriding indicator.
11089 if Comes_From_Source (S) then
11090 Check_Synchronized_Overriding (S, Overridden_Subp);
11092 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
11093 -- it may have overridden some hidden inherited primitive. Update
11094 -- Overridden_Subp to avoid spurious errors when checking the
11095 -- overriding indicator.
11097 if Ada_Version >= Ada_2012
11098 and then No (Overridden_Subp)
11099 and then Is_Dispatching_Operation (S)
11100 and then Present (Overridden_Operation (S))
11102 Overridden_Subp := Overridden_Operation (S);
11105 Check_Overriding_Indicator
11106 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11108 -- The Ghost policy in effect at the point of declaration of a
11109 -- parent subprogram and an overriding subprogram must match
11110 -- (SPARK RM 6.9(17)).
11112 Check_Ghost_Overriding (S, Overridden_Subp);
11115 -- If there is a homonym that is not overloadable, then we have an
11116 -- error, except for the special cases checked explicitly below.
11118 elsif not Is_Overloadable (E) then
11120 -- Check for spurious conflict produced by a subprogram that has the
11121 -- same name as that of the enclosing generic package. The conflict
11122 -- occurs within an instance, between the subprogram and the renaming
11123 -- declaration for the package. After the subprogram, the package
11124 -- renaming declaration becomes hidden.
11126 if Ekind (E) = E_Package
11127 and then Present (Renamed_Object (E))
11128 and then Renamed_Object (E) = Current_Scope
11129 and then Nkind (Parent (Renamed_Object (E))) =
11130 N_Package_Specification
11131 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
11134 Set_Is_Immediately_Visible (E, False);
11135 Enter_Overloaded_Entity (S);
11136 Set_Homonym (S, Homonym (E));
11137 Check_Dispatching_Operation (S, Empty);
11138 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
11140 -- If the subprogram is implicit it is hidden by the previous
11141 -- declaration. However if it is dispatching, it must appear in the
11142 -- dispatch table anyway, because it can be dispatched to even if it
11143 -- cannot be called directly.
11145 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
11146 Set_Scope (S, Current_Scope);
11148 if Is_Dispatching_Operation (Alias (S)) then
11149 Check_Dispatching_Operation (S, Empty);
11155 Report_Conflict (S, E);
11159 -- E exists and is overloadable
11162 Check_Synchronized_Overriding (S, Overridden_Subp);
11164 -- Loop through E and its homonyms to determine if any of them is
11165 -- the candidate for overriding by S.
11167 while Present (E) loop
11169 -- Definitely not interesting if not in the current scope
11171 if Scope (E) /= Current_Scope then
11174 -- A function can overload the name of an abstract state. The
11175 -- state can be viewed as a function with a profile that cannot
11176 -- be matched by anything.
11178 elsif Ekind (S) = E_Function
11179 and then Ekind (E) = E_Abstract_State
11181 Enter_Overloaded_Entity (S);
11184 -- Ada 2012 (AI05-0165): For internally generated bodies of null
11185 -- procedures locate the internally generated spec. We enforce
11186 -- mode conformance since a tagged type may inherit from
11187 -- interfaces several null primitives which differ only in
11188 -- the mode of the formals.
11190 elsif not Comes_From_Source (S)
11191 and then Is_Null_Procedure (S)
11192 and then not Mode_Conformant (E, S)
11196 -- Check if we have type conformance
11198 elsif Type_Conformant (E, S) then
11200 -- If the old and new entities have the same profile and one
11201 -- is not the body of the other, then this is an error, unless
11202 -- one of them is implicitly declared.
11204 -- There are some cases when both can be implicit, for example
11205 -- when both a literal and a function that overrides it are
11206 -- inherited in a derivation, or when an inherited operation
11207 -- of a tagged full type overrides the inherited operation of
11208 -- a private extension. Ada 83 had a special rule for the
11209 -- literal case. In Ada 95, the later implicit operation hides
11210 -- the former, and the literal is always the former. In the
11211 -- odd case where both are derived operations declared at the
11212 -- same point, both operations should be declared, and in that
11213 -- case we bypass the following test and proceed to the next
11214 -- part. This can only occur for certain obscure cases in
11215 -- instances, when an operation on a type derived from a formal
11216 -- private type does not override a homograph inherited from
11217 -- the actual. In subsequent derivations of such a type, the
11218 -- DT positions of these operations remain distinct, if they
11221 if Present (Alias (S))
11222 and then (No (Alias (E))
11223 or else Comes_From_Source (E)
11224 or else Is_Abstract_Subprogram (S)
11226 (Is_Dispatching_Operation (E)
11227 and then Is_Overriding_Alias (E, S)))
11228 and then Ekind (E) /= E_Enumeration_Literal
11230 -- When an derived operation is overloaded it may be due to
11231 -- the fact that the full view of a private extension
11232 -- re-inherits. It has to be dealt with.
11234 if Is_Package_Or_Generic_Package (Current_Scope)
11235 and then In_Private_Part (Current_Scope)
11237 Check_Operation_From_Private_View (S, E);
11240 -- In any case the implicit operation remains hidden by the
11241 -- existing declaration, which is overriding. Indicate that
11242 -- E overrides the operation from which S is inherited.
11244 if Present (Alias (S)) then
11245 Set_Overridden_Operation (E, Alias (S));
11246 Inherit_Subprogram_Contract (E, Alias (S));
11249 Set_Overridden_Operation (E, S);
11250 Inherit_Subprogram_Contract (E, S);
11253 if Comes_From_Source (E) then
11254 Check_Overriding_Indicator (E, S, Is_Primitive => False);
11256 -- The Ghost policy in effect at the point of declaration
11257 -- of a parent subprogram and an overriding subprogram
11258 -- must match (SPARK RM 6.9(17)).
11260 Check_Ghost_Overriding (E, S);
11265 -- Within an instance, the renaming declarations for actual
11266 -- subprograms may become ambiguous, but they do not hide each
11269 elsif Ekind (E) /= E_Entry
11270 and then not Comes_From_Source (E)
11271 and then not Is_Generic_Instance (E)
11272 and then (Present (Alias (E))
11273 or else Is_Intrinsic_Subprogram (E))
11274 and then (not In_Instance
11275 or else No (Parent (E))
11276 or else Nkind (Unit_Declaration_Node (E)) /=
11277 N_Subprogram_Renaming_Declaration)
11279 -- A subprogram child unit is not allowed to override an
11280 -- inherited subprogram (10.1.1(20)).
11282 if Is_Child_Unit (S) then
11284 ("child unit overrides inherited subprogram in parent",
11289 if Is_Non_Overriding_Operation (E, S) then
11290 Enter_Overloaded_Entity (S);
11292 if No (Derived_Type)
11293 or else Is_Tagged_Type (Derived_Type)
11295 Check_Dispatching_Operation (S, Empty);
11301 -- E is a derived operation or an internal operator which
11302 -- is being overridden. Remove E from further visibility.
11303 -- Furthermore, if E is a dispatching operation, it must be
11304 -- replaced in the list of primitive operations of its type
11305 -- (see Override_Dispatching_Operation).
11307 Overridden_Subp := E;
11309 -- It is possible for E to be in the current scope and
11310 -- yet not in the entity chain. This can only occur in a
11311 -- generic context where E is an implicit concatenation
11312 -- in the formal part, because in a generic body the
11313 -- entity chain starts with the formals.
11315 -- In GNATprove mode, a wrapper for an operation with
11316 -- axiomatization may be a homonym of another declaration
11317 -- for an actual subprogram (needs refinement ???).
11319 if No (Prev_Entity (E)) then
11321 and then GNATprove_Mode
11323 Nkind (Original_Node (Unit_Declaration_Node (S))) =
11324 N_Subprogram_Renaming_Declaration
11328 pragma Assert (Chars (E) = Name_Op_Concat);
11333 -- E must be removed both from the entity_list of the
11334 -- current scope, and from the visibility chain.
11336 if Debug_Flag_E then
11337 Write_Str ("Override implicit operation ");
11338 Write_Int (Int (E));
11342 -- If E is a predefined concatenation, it stands for four
11343 -- different operations. As a result, a single explicit
11344 -- declaration does not hide it. In a possible ambiguous
11345 -- situation, Disambiguate chooses the user-defined op,
11346 -- so it is correct to retain the previous internal one.
11348 if Chars (E) /= Name_Op_Concat
11349 or else Ekind (E) /= E_Operator
11351 -- For nondispatching derived operations that are
11352 -- overridden by a subprogram declared in the private
11353 -- part of a package, we retain the derived subprogram
11354 -- but mark it as not immediately visible. If the
11355 -- derived operation was declared in the visible part
11356 -- then this ensures that it will still be visible
11357 -- outside the package with the proper signature
11358 -- (calls from outside must also be directed to this
11359 -- version rather than the overriding one, unlike the
11360 -- dispatching case). Calls from inside the package
11361 -- will still resolve to the overriding subprogram
11362 -- since the derived one is marked as not visible
11363 -- within the package.
11365 -- If the private operation is dispatching, we achieve
11366 -- the overriding by keeping the implicit operation
11367 -- but setting its alias to be the overriding one. In
11368 -- this fashion the proper body is executed in all
11369 -- cases, but the original signature is used outside
11372 -- If the overriding is not in the private part, we
11373 -- remove the implicit operation altogether.
11375 if Is_Private_Declaration (S) then
11376 if not Is_Dispatching_Operation (E) then
11377 Set_Is_Immediately_Visible (E, False);
11379 -- Work done in Override_Dispatching_Operation, so
11380 -- nothing else needs to be done here.
11386 Remove_Entity_And_Homonym (E);
11390 Enter_Overloaded_Entity (S);
11392 -- For entities generated by Derive_Subprograms the
11393 -- overridden operation is the inherited primitive
11394 -- (which is available through the attribute alias).
11396 if not (Comes_From_Source (E))
11397 and then Is_Dispatching_Operation (E)
11398 and then Find_Dispatching_Type (E) =
11399 Find_Dispatching_Type (S)
11400 and then Present (Alias (E))
11401 and then Comes_From_Source (Alias (E))
11403 Set_Overridden_Operation (S, Alias (E));
11404 Inherit_Subprogram_Contract (S, Alias (E));
11406 -- Normal case of setting entity as overridden
11408 -- Note: Static_Initialization and Overridden_Operation
11409 -- attributes use the same field in subprogram entities.
11410 -- Static_Initialization is only defined for internal
11411 -- initialization procedures, where Overridden_Operation
11412 -- is irrelevant. Therefore the setting of this attribute
11413 -- must check whether the target is an init_proc.
11415 elsif not Is_Init_Proc (S) then
11416 Set_Overridden_Operation (S, E);
11417 Inherit_Subprogram_Contract (S, E);
11420 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11422 -- The Ghost policy in effect at the point of declaration
11423 -- of a parent subprogram and an overriding subprogram
11424 -- must match (SPARK RM 6.9(17)).
11426 Check_Ghost_Overriding (S, E);
11428 -- If S is a user-defined subprogram or a null procedure
11429 -- expanded to override an inherited null procedure, or a
11430 -- predefined dispatching primitive then indicate that E
11431 -- overrides the operation from which S is inherited.
11433 if Comes_From_Source (S)
11435 (Present (Parent (S))
11436 and then Nkind (Parent (S)) = N_Procedure_Specification
11437 and then Null_Present (Parent (S)))
11439 (Present (Alias (E))
11441 Is_Predefined_Dispatching_Operation (Alias (E)))
11443 if Present (Alias (E)) then
11444 Set_Overridden_Operation (S, Alias (E));
11445 Inherit_Subprogram_Contract (S, Alias (E));
11449 if Is_Dispatching_Operation (E) then
11451 -- An overriding dispatching subprogram inherits the
11452 -- convention of the overridden subprogram (AI-117).
11454 Set_Convention (S, Convention (E));
11455 Check_Dispatching_Operation (S, E);
11458 Check_Dispatching_Operation (S, Empty);
11461 Check_For_Primitive_Subprogram
11462 (Is_Primitive_Subp, Is_Overriding => True);
11463 goto Check_Inequality;
11465 -- Apparent redeclarations in instances can occur when two
11466 -- formal types get the same actual type. The subprograms in
11467 -- in the instance are legal, even if not callable from the
11468 -- outside. Calls from within are disambiguated elsewhere.
11469 -- For dispatching operations in the visible part, the usual
11470 -- rules apply, and operations with the same profile are not
11471 -- legal (B830001).
11473 elsif (In_Instance_Visible_Part
11474 and then not Is_Dispatching_Operation (E))
11475 or else In_Instance_Not_Visible
11479 -- Here we have a real error (identical profile)
11482 Error_Msg_Sloc := Sloc (E);
11484 -- Avoid cascaded errors if the entity appears in
11485 -- subsequent calls.
11487 Set_Scope (S, Current_Scope);
11489 -- Generate error, with extra useful warning for the case
11490 -- of a generic instance with no completion.
11492 if Is_Generic_Instance (S)
11493 and then not Has_Completion (E)
11496 ("instantiation cannot provide body for&", S);
11497 Error_Msg_N ("\& conflicts with declaration#", S);
11499 Error_Msg_N ("& conflicts with declaration#", S);
11506 -- If one subprogram has an access parameter and the other
11507 -- a parameter of an access type, calls to either might be
11508 -- ambiguous. Verify that parameters match except for the
11509 -- access parameter.
11511 if May_Hide_Profile then
11517 F1 := First_Formal (S);
11518 F2 := First_Formal (E);
11519 while Present (F1) and then Present (F2) loop
11520 if Is_Access_Type (Etype (F1)) then
11521 if not Is_Access_Type (Etype (F2))
11522 or else not Conforming_Types
11523 (Designated_Type (Etype (F1)),
11524 Designated_Type (Etype (F2)),
11527 May_Hide_Profile := False;
11531 not Conforming_Types
11532 (Etype (F1), Etype (F2), Type_Conformant)
11534 May_Hide_Profile := False;
11541 if May_Hide_Profile
11545 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11554 -- On exit, we know that S is a new entity
11556 Enter_Overloaded_Entity (S);
11557 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11558 Check_Overriding_Indicator
11559 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11561 -- The Ghost policy in effect at the point of declaration of a parent
11562 -- subprogram and an overriding subprogram must match
11563 -- (SPARK RM 6.9(17)).
11565 Check_Ghost_Overriding (S, Overridden_Subp);
11567 -- Overloading is not allowed in SPARK, except for operators
11569 if Nkind (S) /= N_Defining_Operator_Symbol then
11570 Error_Msg_Sloc := Sloc (Homonym (S));
11571 Check_SPARK_05_Restriction
11572 ("overloading not allowed with entity#", S);
11575 -- If S is a derived operation for an untagged type then by
11576 -- definition it's not a dispatching operation (even if the parent
11577 -- operation was dispatching), so Check_Dispatching_Operation is not
11578 -- called in that case.
11580 if No (Derived_Type)
11581 or else Is_Tagged_Type (Derived_Type)
11583 Check_Dispatching_Operation (S, Empty);
11587 -- If this is a user-defined equality operator that is not a derived
11588 -- subprogram, create the corresponding inequality. If the operation is
11589 -- dispatching, the expansion is done elsewhere, and we do not create
11590 -- an explicit inequality operation.
11592 <<Check_Inequality>>
11593 if Chars (S) = Name_Op_Eq
11594 and then Etype (S) = Standard_Boolean
11595 and then Present (Parent (S))
11596 and then not Is_Dispatching_Operation (S)
11598 Make_Inequality_Operator (S);
11599 Check_Untagged_Equality (S);
11601 end New_Overloaded_Entity;
11603 ----------------------------------
11604 -- Preanalyze_Formal_Expression --
11605 ----------------------------------
11607 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id) is
11608 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
11610 In_Spec_Expression := True;
11611 Preanalyze_With_Freezing_And_Resolve (N, T);
11612 In_Spec_Expression := Save_In_Spec_Expression;
11613 end Preanalyze_Formal_Expression;
11615 ---------------------
11616 -- Process_Formals --
11617 ---------------------
11619 procedure Process_Formals
11621 Related_Nod : Node_Id)
11623 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11624 -- Determine whether an access type designates a type coming from a
11627 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11628 -- Check whether the default has a class-wide type. After analysis the
11629 -- default has the type of the formal, so we must also check explicitly
11630 -- for an access attribute.
11632 ----------------------------------
11633 -- Designates_From_Limited_With --
11634 ----------------------------------
11636 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11637 Desig : Entity_Id := Typ;
11640 if Is_Access_Type (Desig) then
11641 Desig := Directly_Designated_Type (Desig);
11644 if Is_Class_Wide_Type (Desig) then
11645 Desig := Root_Type (Desig);
11649 Ekind (Desig) = E_Incomplete_Type
11650 and then From_Limited_With (Desig);
11651 end Designates_From_Limited_With;
11653 ---------------------------
11654 -- Is_Class_Wide_Default --
11655 ---------------------------
11657 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11659 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11660 or else (Nkind (D) = N_Attribute_Reference
11661 and then Attribute_Name (D) = Name_Access
11662 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11663 end Is_Class_Wide_Default;
11667 Context : constant Node_Id := Parent (Parent (T));
11669 Formal : Entity_Id;
11670 Formal_Type : Entity_Id;
11671 Param_Spec : Node_Id;
11674 Num_Out_Params : Nat := 0;
11675 First_Out_Param : Entity_Id := Empty;
11676 -- Used for setting Is_Only_Out_Parameter
11678 -- Start of processing for Process_Formals
11681 -- In order to prevent premature use of the formals in the same formal
11682 -- part, the Ekind is left undefined until all default expressions are
11683 -- analyzed. The Ekind is established in a separate loop at the end.
11685 Param_Spec := First (T);
11686 while Present (Param_Spec) loop
11687 Formal := Defining_Identifier (Param_Spec);
11688 Set_Never_Set_In_Source (Formal, True);
11689 Enter_Name (Formal);
11691 -- Case of ordinary parameters
11693 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11694 Find_Type (Parameter_Type (Param_Spec));
11695 Ptype := Parameter_Type (Param_Spec);
11697 if Ptype = Error then
11701 -- Protect against malformed parameter types
11703 if Nkind (Ptype) not in N_Has_Entity then
11704 Formal_Type := Any_Type;
11706 Formal_Type := Entity (Ptype);
11709 if Is_Incomplete_Type (Formal_Type)
11711 (Is_Class_Wide_Type (Formal_Type)
11712 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11714 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11715 -- primitive operations, as long as their completion is
11716 -- in the same declarative part. If in the private part
11717 -- this means that the type cannot be a Taft-amendment type.
11718 -- Check is done on package exit. For access to subprograms,
11719 -- the use is legal for Taft-amendment types.
11721 -- Ada 2012: tagged incomplete types are allowed as generic
11722 -- formal types. They do not introduce dependencies and the
11723 -- corresponding generic subprogram does not have a delayed
11724 -- freeze, because it does not need a freeze node. However,
11725 -- it is still the case that untagged incomplete types cannot
11726 -- be Taft-amendment types and must be completed in private
11727 -- part, so the subprogram must appear in the list of private
11728 -- dependents of the type.
11730 if Is_Tagged_Type (Formal_Type)
11731 or else (Ada_Version >= Ada_2012
11732 and then not From_Limited_With (Formal_Type)
11733 and then not Is_Generic_Type (Formal_Type))
11735 if Ekind (Scope (Current_Scope)) = E_Package
11736 and then not Is_Generic_Type (Formal_Type)
11737 and then not Is_Class_Wide_Type (Formal_Type)
11740 (Parent (T), N_Access_Function_Definition,
11741 N_Access_Procedure_Definition)
11743 Append_Elmt (Current_Scope,
11744 Private_Dependents (Base_Type (Formal_Type)));
11746 -- Freezing is delayed to ensure that Register_Prim
11747 -- will get called for this operation, which is needed
11748 -- in cases where static dispatch tables aren't built.
11749 -- (Note that the same is done for controlling access
11750 -- parameter cases in function Access_Definition.)
11752 if not Is_Thunk (Current_Scope) then
11753 Set_Has_Delayed_Freeze (Current_Scope);
11758 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11759 N_Access_Procedure_Definition)
11761 -- AI05-0151: Tagged incomplete types are allowed in all
11762 -- formal parts. Untagged incomplete types are not allowed
11763 -- in bodies. Limited views of either kind are not allowed
11764 -- if there is no place at which the non-limited view can
11765 -- become available.
11767 -- Incomplete formal untagged types are not allowed in
11768 -- subprogram bodies (but are legal in their declarations).
11769 -- This excludes bodies created for null procedures, which
11770 -- are basic declarations.
11772 if Is_Generic_Type (Formal_Type)
11773 and then not Is_Tagged_Type (Formal_Type)
11774 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11777 ("invalid use of formal incomplete type", Param_Spec);
11779 elsif Ada_Version >= Ada_2012 then
11780 if Is_Tagged_Type (Formal_Type)
11781 and then (not From_Limited_With (Formal_Type)
11782 or else not In_Package_Body)
11786 elsif Nkind_In (Context, N_Accept_Statement,
11787 N_Accept_Alternative,
11789 or else (Nkind (Context) = N_Subprogram_Body
11790 and then Comes_From_Source (Context))
11793 ("invalid use of untagged incomplete type &",
11794 Ptype, Formal_Type);
11799 ("invalid use of incomplete type&",
11800 Param_Spec, Formal_Type);
11802 -- Further checks on the legality of incomplete types
11803 -- in formal parts are delayed until the freeze point
11804 -- of the enclosing subprogram or access to subprogram.
11808 elsif Ekind (Formal_Type) = E_Void then
11810 ("premature use of&",
11811 Parameter_Type (Param_Spec), Formal_Type);
11814 -- Ada 2012 (AI-142): Handle aliased parameters
11816 if Ada_Version >= Ada_2012
11817 and then Aliased_Present (Param_Spec)
11819 Set_Is_Aliased (Formal);
11821 -- AI12-001: All aliased objects are considered to be specified
11822 -- as independently addressable (RM C.6(8.1/4)).
11824 Set_Is_Independent (Formal);
11827 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11828 -- declaration corresponding to the null-excluding type of the
11829 -- formal in the enclosing scope. Finally, replace the parameter
11830 -- type of the formal with the internal subtype.
11832 if Ada_Version >= Ada_2005
11833 and then Null_Exclusion_Present (Param_Spec)
11835 if not Is_Access_Type (Formal_Type) then
11837 ("`NOT NULL` allowed only for an access type", Param_Spec);
11840 if Can_Never_Be_Null (Formal_Type)
11841 and then Comes_From_Source (Related_Nod)
11844 ("`NOT NULL` not allowed (& already excludes null)",
11845 Param_Spec, Formal_Type);
11849 Create_Null_Excluding_Itype
11851 Related_Nod => Related_Nod,
11852 Scope_Id => Scope (Current_Scope));
11854 -- If the designated type of the itype is an itype that is
11855 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11856 -- on the access subtype, to prevent order-of-elaboration
11857 -- issues in the backend.
11860 -- type T is access procedure;
11861 -- procedure Op (O : not null T);
11863 if Is_Itype (Directly_Designated_Type (Formal_Type))
11865 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11867 Set_Has_Delayed_Freeze (Formal_Type);
11872 -- An access formal type
11876 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11878 -- No need to continue if we already notified errors
11880 if not Present (Formal_Type) then
11884 -- Ada 2005 (AI-254)
11887 AD : constant Node_Id :=
11888 Access_To_Subprogram_Definition
11889 (Parameter_Type (Param_Spec));
11891 if Present (AD) and then Protected_Present (AD) then
11893 Replace_Anonymous_Access_To_Protected_Subprogram
11899 Set_Etype (Formal, Formal_Type);
11901 -- Deal with default expression if present
11903 Default := Expression (Param_Spec);
11905 if Present (Default) then
11906 Check_SPARK_05_Restriction
11907 ("default expression is not allowed", Default);
11909 if Out_Present (Param_Spec) then
11911 ("default initialization only allowed for IN parameters",
11915 -- Do the special preanalysis of the expression (see section on
11916 -- "Handling of Default Expressions" in the spec of package Sem).
11918 Preanalyze_Formal_Expression (Default, Formal_Type);
11920 -- An access to constant cannot be the default for
11921 -- an access parameter that is an access to variable.
11923 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11924 and then not Is_Access_Constant (Formal_Type)
11925 and then Is_Access_Type (Etype (Default))
11926 and then Is_Access_Constant (Etype (Default))
11929 ("formal that is access to variable cannot be initialized "
11930 & "with an access-to-constant expression", Default);
11933 -- Check that the designated type of an access parameter's default
11934 -- is not a class-wide type unless the parameter's designated type
11935 -- is also class-wide.
11937 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11938 and then not Designates_From_Limited_With (Formal_Type)
11939 and then Is_Class_Wide_Default (Default)
11940 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11943 ("access to class-wide expression not allowed here", Default);
11946 -- Check incorrect use of dynamically tagged expressions
11948 if Is_Tagged_Type (Formal_Type) then
11949 Check_Dynamically_Tagged_Expression
11951 Typ => Formal_Type,
11952 Related_Nod => Default);
11956 -- Ada 2005 (AI-231): Static checks
11958 if Ada_Version >= Ada_2005
11959 and then Is_Access_Type (Etype (Formal))
11960 and then Can_Never_Be_Null (Etype (Formal))
11962 Null_Exclusion_Static_Checks (Param_Spec);
11965 -- The following checks are relevant only when SPARK_Mode is on as
11966 -- these are not standard Ada legality rules.
11968 if SPARK_Mode = On then
11969 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11971 -- A function cannot have a parameter of mode IN OUT or OUT
11974 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11976 ("function cannot have parameter of mode `OUT` or "
11977 & "`IN OUT`", Formal);
11980 -- A procedure cannot have an effectively volatile formal
11981 -- parameter of mode IN because it behaves as a constant
11982 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11984 elsif Ekind (Scope (Formal)) = E_Procedure
11985 and then Ekind (Formal) = E_In_Parameter
11986 and then Is_Effectively_Volatile (Formal)
11989 ("formal parameter of mode `IN` cannot be volatile", Formal);
11997 -- If this is the formal part of a function specification, analyze the
11998 -- subtype mark in the context where the formals are visible but not
11999 -- yet usable, and may hide outer homographs.
12001 if Nkind (Related_Nod) = N_Function_Specification then
12002 Analyze_Return_Type (Related_Nod);
12005 -- Now set the kind (mode) of each formal
12007 Param_Spec := First (T);
12008 while Present (Param_Spec) loop
12009 Formal := Defining_Identifier (Param_Spec);
12010 Set_Formal_Mode (Formal);
12012 if Ekind (Formal) = E_In_Parameter then
12013 Set_Default_Value (Formal, Expression (Param_Spec));
12015 if Present (Expression (Param_Spec)) then
12016 Default := Expression (Param_Spec);
12018 if Is_Scalar_Type (Etype (Default)) then
12019 if Nkind (Parameter_Type (Param_Spec)) /=
12020 N_Access_Definition
12022 Formal_Type := Entity (Parameter_Type (Param_Spec));
12026 (Related_Nod, Parameter_Type (Param_Spec));
12029 Apply_Scalar_Range_Check (Default, Formal_Type);
12033 elsif Ekind (Formal) = E_Out_Parameter then
12034 Num_Out_Params := Num_Out_Params + 1;
12036 if Num_Out_Params = 1 then
12037 First_Out_Param := Formal;
12040 elsif Ekind (Formal) = E_In_Out_Parameter then
12041 Num_Out_Params := Num_Out_Params + 1;
12044 -- Skip remaining processing if formal type was in error
12046 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
12047 goto Next_Parameter;
12050 -- Force call by reference if aliased
12053 Conv : constant Convention_Id := Convention (Etype (Formal));
12055 if Is_Aliased (Formal) then
12056 Set_Mechanism (Formal, By_Reference);
12058 -- Warn if user asked this to be passed by copy
12060 if Conv = Convention_Ada_Pass_By_Copy then
12062 ("cannot pass aliased parameter & by copy??", Formal);
12065 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
12067 elsif Conv = Convention_Ada_Pass_By_Copy then
12068 Set_Mechanism (Formal, By_Copy);
12070 elsif Conv = Convention_Ada_Pass_By_Reference then
12071 Set_Mechanism (Formal, By_Reference);
12079 if Present (First_Out_Param) and then Num_Out_Params = 1 then
12080 Set_Is_Only_Out_Parameter (First_Out_Param);
12082 end Process_Formals;
12084 ----------------------------
12085 -- Reference_Body_Formals --
12086 ----------------------------
12088 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
12093 if Error_Posted (Spec) then
12097 -- Iterate over both lists. They may be of different lengths if the two
12098 -- specs are not conformant.
12100 Fs := First_Formal (Spec);
12101 Fb := First_Formal (Bod);
12102 while Present (Fs) and then Present (Fb) loop
12103 Generate_Reference (Fs, Fb, 'b');
12105 if Style_Check then
12106 Style.Check_Identifier (Fb, Fs);
12109 Set_Spec_Entity (Fb, Fs);
12110 Set_Referenced (Fs, False);
12114 end Reference_Body_Formals;
12116 -------------------------
12117 -- Set_Actual_Subtypes --
12118 -------------------------
12120 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
12122 Formal : Entity_Id;
12124 First_Stmt : Node_Id := Empty;
12125 AS_Needed : Boolean;
12128 -- If this is an empty initialization procedure, no need to create
12129 -- actual subtypes (small optimization).
12131 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
12134 -- Within a predicate function we do not want to generate local
12135 -- subtypes that may generate nested predicate functions.
12137 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
12141 -- The subtype declarations may freeze the formals. The body generated
12142 -- for an expression function is not a freeze point, so do not emit
12143 -- these declarations (small loss of efficiency in rare cases).
12145 if Nkind (N) = N_Subprogram_Body
12146 and then Was_Expression_Function (N)
12151 Formal := First_Formal (Subp);
12152 while Present (Formal) loop
12153 T := Etype (Formal);
12155 -- We never need an actual subtype for a constrained formal
12157 if Is_Constrained (T) then
12158 AS_Needed := False;
12160 -- If we have unknown discriminants, then we do not need an actual
12161 -- subtype, or more accurately we cannot figure it out. Note that
12162 -- all class-wide types have unknown discriminants.
12164 elsif Has_Unknown_Discriminants (T) then
12165 AS_Needed := False;
12167 -- At this stage we have an unconstrained type that may need an
12168 -- actual subtype. For sure the actual subtype is needed if we have
12169 -- an unconstrained array type. However, in an instance, the type
12170 -- may appear as a subtype of the full view, while the actual is
12171 -- in fact private (in which case no actual subtype is needed) so
12172 -- check the kind of the base type.
12174 elsif Is_Array_Type (Base_Type (T)) then
12177 -- The only other case needing an actual subtype is an unconstrained
12178 -- record type which is an IN parameter (we cannot generate actual
12179 -- subtypes for the OUT or IN OUT case, since an assignment can
12180 -- change the discriminant values. However we exclude the case of
12181 -- initialization procedures, since discriminants are handled very
12182 -- specially in this context, see the section entitled "Handling of
12183 -- Discriminants" in Einfo.
12185 -- We also exclude the case of Discrim_SO_Functions (functions used
12186 -- in front-end layout mode for size/offset values), since in such
12187 -- functions only discriminants are referenced, and not only are such
12188 -- subtypes not needed, but they cannot always be generated, because
12189 -- of order of elaboration issues.
12191 elsif Is_Record_Type (T)
12192 and then Ekind (Formal) = E_In_Parameter
12193 and then Chars (Formal) /= Name_uInit
12194 and then not Is_Unchecked_Union (T)
12195 and then not Is_Discrim_SO_Function (Subp)
12199 -- All other cases do not need an actual subtype
12202 AS_Needed := False;
12205 -- Generate actual subtypes for unconstrained arrays and
12206 -- unconstrained discriminated records.
12209 if Nkind (N) = N_Accept_Statement then
12211 -- If expansion is active, the formal is replaced by a local
12212 -- variable that renames the corresponding entry of the
12213 -- parameter block, and it is this local variable that may
12214 -- require an actual subtype.
12216 if Expander_Active then
12217 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
12219 Decl := Build_Actual_Subtype (T, Formal);
12222 if Present (Handled_Statement_Sequence (N)) then
12224 First (Statements (Handled_Statement_Sequence (N)));
12225 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
12226 Mark_Rewrite_Insertion (Decl);
12228 -- If the accept statement has no body, there will be no
12229 -- reference to the actuals, so no need to compute actual
12236 Decl := Build_Actual_Subtype (T, Formal);
12237 Prepend (Decl, Declarations (N));
12238 Mark_Rewrite_Insertion (Decl);
12241 -- The declaration uses the bounds of an existing object, and
12242 -- therefore needs no constraint checks.
12244 Analyze (Decl, Suppress => All_Checks);
12245 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
12247 -- We need to freeze manually the generated type when it is
12248 -- inserted anywhere else than in a declarative part.
12250 if Present (First_Stmt) then
12251 Insert_List_Before_And_Analyze (First_Stmt,
12252 Freeze_Entity (Defining_Identifier (Decl), N));
12254 -- Ditto if the type has a dynamic predicate, because the
12255 -- generated function will mention the actual subtype. The
12256 -- predicate may come from an explicit aspect of be inherited.
12258 elsif Has_Predicates (T) then
12259 Insert_List_After_And_Analyze (Decl,
12260 Freeze_Entity (Defining_Identifier (Decl), N));
12263 if Nkind (N) = N_Accept_Statement
12264 and then Expander_Active
12266 Set_Actual_Subtype (Renamed_Object (Formal),
12267 Defining_Identifier (Decl));
12269 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
12273 Next_Formal (Formal);
12275 end Set_Actual_Subtypes;
12277 ---------------------
12278 -- Set_Formal_Mode --
12279 ---------------------
12281 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
12282 Spec : constant Node_Id := Parent (Formal_Id);
12283 Id : constant Entity_Id := Scope (Formal_Id);
12286 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
12287 -- since we ensure that corresponding actuals are always valid at the
12288 -- point of the call.
12290 if Out_Present (Spec) then
12291 if Ekind_In (Id, E_Entry, E_Entry_Family)
12292 or else Is_Subprogram_Or_Generic_Subprogram (Id)
12294 Set_Has_Out_Or_In_Out_Parameter (Id, True);
12297 if Ekind_In (Id, E_Function, E_Generic_Function) then
12299 -- [IN] OUT parameters allowed for functions in Ada 2012
12301 if Ada_Version >= Ada_2012 then
12303 -- Even in Ada 2012 operators can only have IN parameters
12305 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
12306 Error_Msg_N ("operators can only have IN parameters", Spec);
12309 if In_Present (Spec) then
12310 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12312 Set_Ekind (Formal_Id, E_Out_Parameter);
12315 -- But not in earlier versions of Ada
12318 Error_Msg_N ("functions can only have IN parameters", Spec);
12319 Set_Ekind (Formal_Id, E_In_Parameter);
12322 elsif In_Present (Spec) then
12323 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12326 Set_Ekind (Formal_Id, E_Out_Parameter);
12327 Set_Never_Set_In_Source (Formal_Id, True);
12328 Set_Is_True_Constant (Formal_Id, False);
12329 Set_Current_Value (Formal_Id, Empty);
12333 Set_Ekind (Formal_Id, E_In_Parameter);
12336 -- Set Is_Known_Non_Null for access parameters since the language
12337 -- guarantees that access parameters are always non-null. We also set
12338 -- Can_Never_Be_Null, since there is no way to change the value.
12340 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
12342 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
12343 -- null; In Ada 2005, only if then null_exclusion is explicit.
12345 if Ada_Version < Ada_2005
12346 or else Can_Never_Be_Null (Etype (Formal_Id))
12348 Set_Is_Known_Non_Null (Formal_Id);
12349 Set_Can_Never_Be_Null (Formal_Id);
12352 -- Ada 2005 (AI-231): Null-exclusion access subtype
12354 elsif Is_Access_Type (Etype (Formal_Id))
12355 and then Can_Never_Be_Null (Etype (Formal_Id))
12357 Set_Is_Known_Non_Null (Formal_Id);
12359 -- We can also set Can_Never_Be_Null (thus preventing some junk
12360 -- access checks) for the case of an IN parameter, which cannot
12361 -- be changed, or for an IN OUT parameter, which can be changed but
12362 -- not to a null value. But for an OUT parameter, the initial value
12363 -- passed in can be null, so we can't set this flag in that case.
12365 if Ekind (Formal_Id) /= E_Out_Parameter then
12366 Set_Can_Never_Be_Null (Formal_Id);
12370 Set_Mechanism (Formal_Id, Default_Mechanism);
12371 Set_Formal_Validity (Formal_Id);
12372 end Set_Formal_Mode;
12374 -------------------------
12375 -- Set_Formal_Validity --
12376 -------------------------
12378 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12380 -- If no validity checking, then we cannot assume anything about the
12381 -- validity of parameters, since we do not know there is any checking
12382 -- of the validity on the call side.
12384 if not Validity_Checks_On then
12387 -- If validity checking for parameters is enabled, this means we are
12388 -- not supposed to make any assumptions about argument values.
12390 elsif Validity_Check_Parameters then
12393 -- If we are checking in parameters, we will assume that the caller is
12394 -- also checking parameters, so we can assume the parameter is valid.
12396 elsif Ekind (Formal_Id) = E_In_Parameter
12397 and then Validity_Check_In_Params
12399 Set_Is_Known_Valid (Formal_Id, True);
12401 -- Similar treatment for IN OUT parameters
12403 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12404 and then Validity_Check_In_Out_Params
12406 Set_Is_Known_Valid (Formal_Id, True);
12408 end Set_Formal_Validity;
12410 ------------------------
12411 -- Subtype_Conformant --
12412 ------------------------
12414 function Subtype_Conformant
12415 (New_Id : Entity_Id;
12416 Old_Id : Entity_Id;
12417 Skip_Controlling_Formals : Boolean := False) return Boolean
12421 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12422 Skip_Controlling_Formals => Skip_Controlling_Formals);
12424 end Subtype_Conformant;
12426 ---------------------
12427 -- Type_Conformant --
12428 ---------------------
12430 function Type_Conformant
12431 (New_Id : Entity_Id;
12432 Old_Id : Entity_Id;
12433 Skip_Controlling_Formals : Boolean := False) return Boolean
12437 May_Hide_Profile := False;
12439 (New_Id, Old_Id, Type_Conformant, False, Result,
12440 Skip_Controlling_Formals => Skip_Controlling_Formals);
12442 end Type_Conformant;
12444 -------------------------------
12445 -- Valid_Operator_Definition --
12446 -------------------------------
12448 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12451 Id : constant Name_Id := Chars (Designator);
12455 F := First_Formal (Designator);
12456 while Present (F) loop
12459 if Present (Default_Value (F)) then
12461 ("default values not allowed for operator parameters",
12464 -- For function instantiations that are operators, we must check
12465 -- separately that the corresponding generic only has in-parameters.
12466 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12467 -- an error could not arise in earlier versions of the language.
12469 elsif Ekind (F) /= E_In_Parameter then
12470 Error_Msg_N ("operators can only have IN parameters", F);
12476 -- Verify that user-defined operators have proper number of arguments
12477 -- First case of operators which can only be unary
12479 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12482 -- Case of operators which can be unary or binary
12484 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12485 N_OK := (N in 1 .. 2);
12487 -- All other operators can only be binary
12495 ("incorrect number of arguments for operator", Designator);
12499 and then Base_Type (Etype (Designator)) = Standard_Boolean
12500 and then not Is_Intrinsic_Subprogram (Designator)
12503 ("explicit definition of inequality not allowed", Designator);
12505 end Valid_Operator_Definition;