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 Generate_Definition (Subp_Id);
230 -- Set the SPARK mode from the current context (may be overwritten later
231 -- with explicit pragma).
233 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
234 Set_SPARK_Pragma_Inherited (Subp_Id);
236 -- Preserve relevant elaboration-related attributes of the context which
237 -- are no longer available or very expensive to recompute once analysis,
238 -- resolution, and expansion are over.
240 Mark_Elaboration_Attributes
245 Set_Is_Abstract_Subprogram (Subp_Id);
246 New_Overloaded_Entity (Subp_Id);
247 Check_Delayed_Subprogram (Subp_Id);
249 Set_Categorization_From_Scope (Subp_Id, Scop);
251 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
252 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
254 -- Issue a warning if the abstract subprogram is neither a dispatching
255 -- operation nor an operation that overrides an inherited subprogram or
256 -- predefined operator, since this most likely indicates a mistake.
258 elsif Warn_On_Redundant_Constructs
259 and then not Is_Dispatching_Operation (Subp_Id)
260 and then not Present (Overridden_Operation (Subp_Id))
261 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
262 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
265 ("abstract subprogram is not dispatching or overriding?r?", N);
268 Generate_Reference_To_Formals (Subp_Id);
269 Check_Eliminated (Subp_Id);
271 if Has_Aspects (N) then
272 Analyze_Aspect_Specifications (N, Subp_Id);
274 end Analyze_Abstract_Subprogram_Declaration;
276 ---------------------------------
277 -- Analyze_Expression_Function --
278 ---------------------------------
280 procedure Analyze_Expression_Function (N : Node_Id) is
281 Expr : constant Node_Id := Expression (N);
282 Loc : constant Source_Ptr := Sloc (N);
283 LocX : constant Source_Ptr := Sloc (Expr);
284 Spec : constant Node_Id := Specification (N);
294 Def_Id : Entity_Id := Empty;
296 -- If the expression is a completion, Prev is the entity whose
297 -- declaration is completed. Def_Id is needed to analyze the spec.
299 -- Start of processing for Analyze_Expression_Function
302 -- This is one of the occasions on which we transform the tree during
303 -- semantic analysis. If this is a completion, transform the expression
304 -- function into an equivalent subprogram body, and analyze it.
306 -- Expression functions are inlined unconditionally. The back-end will
307 -- determine whether this is possible.
309 Inline_Processing_Required := True;
311 -- Create a specification for the generated body. This must be done
312 -- prior to the analysis of the initial declaration.
314 New_Spec := Copy_Subprogram_Spec (Spec);
315 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
317 -- If there are previous overloadable entities with the same name,
318 -- check whether any of them is completed by the expression function.
319 -- In a generic context a formal subprogram has no completion.
322 and then Is_Overloadable (Prev)
323 and then not Is_Formal_Subprogram (Prev)
325 Def_Id := Analyze_Subprogram_Specification (Spec);
326 Prev := Find_Corresponding_Spec (N);
328 -- The previous entity may be an expression function as well, in
329 -- which case the redeclaration is illegal.
332 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
333 N_Expression_Function
335 Error_Msg_Sloc := Sloc (Prev);
336 Error_Msg_N ("& conflicts with declaration#", Def_Id);
341 Ret := Make_Simple_Return_Statement (LocX, Expr);
344 Make_Subprogram_Body (Loc,
345 Specification => New_Spec,
346 Declarations => Empty_List,
347 Handled_Statement_Sequence =>
348 Make_Handled_Sequence_Of_Statements (LocX,
349 Statements => New_List (Ret)));
350 Set_Was_Expression_Function (New_Body);
352 -- If the expression completes a generic subprogram, we must create a
353 -- separate node for the body, because at instantiation the original
354 -- node of the generic copy must be a generic subprogram body, and
355 -- cannot be a expression function. Otherwise we just rewrite the
356 -- expression with the non-generic body.
358 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
359 Insert_After (N, New_Body);
361 -- Propagate any aspects or pragmas that apply to the expression
362 -- function to the proper body when the expression function acts
365 if Has_Aspects (N) then
366 Move_Aspects (N, To => New_Body);
369 Relocate_Pragmas_To_Body (New_Body);
371 Rewrite (N, Make_Null_Statement (Loc));
372 Set_Has_Completion (Prev, False);
375 Set_Is_Inlined (Prev);
377 -- If the expression function is a completion, the previous declaration
378 -- must come from source. We know already that it appears in the current
379 -- scope. The entity itself may be internally created if within a body
383 and then Is_Overloadable (Prev)
384 and then not Is_Formal_Subprogram (Prev)
385 and then Comes_From_Source (Parent (Prev))
387 Set_Has_Completion (Prev, False);
388 Set_Is_Inlined (Prev);
390 -- AI12-0103: Expression functions that are a completion freeze their
391 -- expression but don't freeze anything else (unlike regular bodies).
393 -- Note that we cannot defer this freezing to the analysis of the
394 -- expression itself, because a freeze node might appear in a nested
395 -- scope, leading to an elaboration order issue in gigi.
396 -- As elsewhere, we do not emit freeze nodes within a generic unit.
398 if not Inside_A_Generic then
401 Typ => Etype (Def_Id),
406 -- For navigation purposes, indicate that the function is a body
408 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
409 Rewrite (N, New_Body);
411 -- Remove any existing aspects from the original node because the act
412 -- of rewriting causes the list to be shared between the two nodes.
414 Orig_N := Original_Node (N);
415 Remove_Aspects (Orig_N);
417 -- Propagate any pragmas that apply to expression function to the
418 -- proper body when the expression function acts as a completion.
419 -- Aspects are automatically transfered because of node rewriting.
421 Relocate_Pragmas_To_Body (N);
424 -- Once the aspects of the generated body have been analyzed, create
425 -- a copy for ASIS purposes and associate it with the original node.
426 -- Is this still needed???
428 if Has_Aspects (N) then
429 Set_Aspect_Specifications (Orig_N,
430 New_Copy_List_Tree (Aspect_Specifications (N)));
433 -- Prev is the previous entity with the same name, but it is can
434 -- be an unrelated spec that is not completed by the expression
435 -- function. In that case the relevant entity is the one in the body.
436 -- Not clear that the backend can inline it in this case ???
438 if Has_Completion (Prev) then
440 -- The formals of the expression function are body formals,
441 -- and do not appear in the ali file, which will only contain
442 -- references to the formals of the original subprogram spec.
449 F1 := First_Formal (Def_Id);
450 F2 := First_Formal (Prev);
452 while Present (F1) loop
453 Set_Spec_Entity (F1, F2);
460 Set_Is_Inlined (Defining_Entity (New_Body));
463 -- If this is not a completion, create both a declaration and a body, so
464 -- that the expression can be inlined whenever possible.
467 -- An expression function that is not a completion is not a
468 -- subprogram declaration, and thus cannot appear in a protected
471 if Nkind (Parent (N)) = N_Protected_Definition then
473 ("an expression function is not a legal protected operation", N);
476 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
478 -- Remove any existing aspects from the original node because the act
479 -- of rewriting causes the list to be shared between the two nodes.
481 Orig_N := Original_Node (N);
482 Remove_Aspects (Orig_N);
486 -- Once the aspects of the generated spec have been analyzed, create
487 -- a copy for ASIS purposes and associate it with the original node.
488 -- Is this still needed???
490 if Has_Aspects (N) then
491 Set_Aspect_Specifications (Orig_N,
492 New_Copy_List_Tree (Aspect_Specifications (N)));
495 -- If aspect SPARK_Mode was specified on the body, it needs to be
496 -- repeated both on the generated spec and the body.
498 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
500 if Present (Asp) then
501 Asp := New_Copy_Tree (Asp);
502 Set_Analyzed (Asp, False);
503 Set_Aspect_Specifications (New_Body, New_List (Asp));
506 Def_Id := Defining_Entity (N);
507 Set_Is_Inlined (Def_Id);
509 -- Establish the linkages between the spec and the body. These are
510 -- used when the expression function acts as the prefix of attribute
511 -- 'Access in order to freeze the original expression which has been
512 -- moved to the generated body.
514 Set_Corresponding_Body (N, Defining_Entity (New_Body));
515 Set_Corresponding_Spec (New_Body, Def_Id);
517 -- Within a generic preanalyze the original expression for name
518 -- capture. The body is also generated but plays no role in
519 -- this because it is not part of the original source.
521 if Inside_A_Generic then
522 Set_Has_Completion (Def_Id);
524 Install_Formals (Def_Id);
525 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
529 -- To prevent premature freeze action, insert the new body at the end
530 -- of the current declarations, or at the end of the package spec.
531 -- However, resolve usage names now, to prevent spurious visibility
532 -- on later entities. Note that the function can now be called in
533 -- the current declarative part, which will appear to be prior to
534 -- the presence of the body in the code. There are nevertheless no
535 -- order of elaboration issues because all name resolution has taken
536 -- place at the point of declaration.
539 Decls : List_Id := List_Containing (N);
540 Expr : constant Node_Id := Expression (Ret);
541 Par : constant Node_Id := Parent (Decls);
542 Typ : constant Entity_Id := Etype (Def_Id);
545 -- If this is a wrapper created for in an instance for a formal
546 -- subprogram, insert body after declaration, to be analyzed when
547 -- the enclosing instance is analyzed.
550 and then Is_Generic_Actual_Subprogram (Def_Id)
552 Insert_After (N, New_Body);
555 if Nkind (Par) = N_Package_Specification
556 and then Decls = Visible_Declarations (Par)
557 and then Present (Private_Declarations (Par))
558 and then not Is_Empty_List (Private_Declarations (Par))
560 Decls := Private_Declarations (Par);
563 Insert_After (Last (Decls), New_Body);
565 -- Preanalyze the expression if not already done above
567 if not Inside_A_Generic then
569 Install_Formals (Def_Id);
570 Preanalyze_Formal_Expression (Expr, Typ);
571 Check_Limited_Return (Original_Node (N), Expr, Typ);
578 -- Check incorrect use of dynamically tagged expression. This doesn't
579 -- fall out automatically when analyzing the generated function body,
580 -- because Check_Dynamically_Tagged_Expression deliberately ignores
581 -- nodes that don't come from source.
584 and then Nkind (Def_Id) in N_Has_Etype
585 and then Is_Tagged_Type (Etype (Def_Id))
587 Check_Dynamically_Tagged_Expression
589 Typ => Etype (Def_Id),
590 Related_Nod => Original_Node (N));
593 -- We must enforce checks for unreferenced formals in our newly
594 -- generated function, so we propagate the referenced flag from the
595 -- original spec to the new spec as well as setting Comes_From_Source.
597 if Present (Parameter_Specifications (New_Spec)) then
599 Form_New_Def : Entity_Id;
600 Form_New_Spec : Entity_Id;
601 Form_Old_Def : Entity_Id;
602 Form_Old_Spec : Entity_Id;
605 Form_New_Spec := First (Parameter_Specifications (New_Spec));
606 Form_Old_Spec := First (Parameter_Specifications (Spec));
608 while Present (Form_New_Spec) and then Present (Form_Old_Spec) loop
609 Form_New_Def := Defining_Identifier (Form_New_Spec);
610 Form_Old_Def := Defining_Identifier (Form_Old_Spec);
612 Set_Comes_From_Source (Form_New_Def, True);
614 -- Because of the usefulness of unreferenced controlling
615 -- formals we exempt them from unreferenced warnings by marking
616 -- them as always referenced.
618 Set_Referenced (Form_Old_Def,
619 (Is_Formal (Form_Old_Def)
620 and then Is_Controlling_Formal (Form_Old_Def))
621 or else Referenced (Form_Old_Def));
623 Next (Form_New_Spec);
624 Next (Form_Old_Spec);
628 end Analyze_Expression_Function;
630 ----------------------------------------
631 -- Analyze_Extended_Return_Statement --
632 ----------------------------------------
634 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
636 Check_Compiler_Unit ("extended return statement", N);
637 Analyze_Return_Statement (N);
638 end Analyze_Extended_Return_Statement;
640 ----------------------------
641 -- Analyze_Function_Call --
642 ----------------------------
644 procedure Analyze_Function_Call (N : Node_Id) is
645 Actuals : constant List_Id := Parameter_Associations (N);
646 Func_Nam : constant Node_Id := Name (N);
652 -- A call of the form A.B (X) may be an Ada 2005 call, which is
653 -- rewritten as B (A, X). If the rewriting is successful, the call
654 -- has been analyzed and we just return.
656 if Nkind (Func_Nam) = N_Selected_Component
657 and then Name (N) /= Func_Nam
658 and then Is_Rewrite_Substitution (N)
659 and then Present (Etype (N))
664 -- If error analyzing name, then set Any_Type as result type and return
666 if Etype (Func_Nam) = Any_Type then
667 Set_Etype (N, Any_Type);
671 -- Otherwise analyze the parameters
673 if Present (Actuals) then
674 Actual := First (Actuals);
675 while Present (Actual) loop
677 Check_Parameterless_Call (Actual);
683 end Analyze_Function_Call;
685 -----------------------------
686 -- Analyze_Function_Return --
687 -----------------------------
689 procedure Analyze_Function_Return (N : Node_Id) is
690 Loc : constant Source_Ptr := Sloc (N);
691 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
692 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
694 R_Type : constant Entity_Id := Etype (Scope_Id);
695 -- Function result subtype
697 procedure Check_Return_Construct_Accessibility (Return_Stmt : Node_Id);
698 -- Apply legality rule of 6.5 (5.9) to the access discriminants of an
699 -- aggregate in a return statement.
701 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
702 -- Check that the return_subtype_indication properly matches the result
703 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
705 ------------------------------------------
706 -- Check_Return_Construct_Accessibility --
707 ------------------------------------------
709 procedure Check_Return_Construct_Accessibility (Return_Stmt : Node_Id) is
711 Agg : Node_Id := Empty;
715 Process_Exprs : Boolean := False;
716 Return_Con : Node_Id;
719 -- Only perform checks on record types with access discriminants and
720 -- non-internally generated functions.
722 if not Is_Record_Type (R_Type)
723 or else not Has_Discriminants (R_Type)
724 or else not Comes_From_Source (Return_Stmt)
729 -- We are only interested in return statements
731 if not Nkind_In (Return_Stmt, N_Extended_Return_Statement,
732 N_Simple_Return_Statement)
737 -- Fetch the object from the return statement, in the case of a
738 -- simple return statement the expression is part of the node.
740 if Nkind (Return_Stmt) = N_Extended_Return_Statement then
741 -- Obtain the object definition from the expanded extended return
743 Return_Con := First (Return_Object_Declarations (Return_Stmt));
744 while Present (Return_Con) loop
745 -- Inspect the original node to avoid object declarations
746 -- expanded into renamings.
748 if Nkind (Original_Node (Return_Con)) = N_Object_Declaration
749 and then Comes_From_Source (Original_Node (Return_Con))
754 Nlists.Next (Return_Con);
757 pragma Assert (Present (Return_Con));
759 -- Could be dealing with a renaming
761 Return_Con := Original_Node (Return_Con);
763 Return_Con := Return_Stmt;
766 -- We may need to check an aggregate or a subtype indication
767 -- depending on how the discriminants were specified and whether
768 -- we are looking at an extended return statement.
770 if Nkind (Return_Con) = N_Object_Declaration
771 and then Nkind (Object_Definition (Return_Con))
772 = N_Subtype_Indication
774 Assoc := Original_Node
777 (Constraint (Object_Definition (Return_Con)))));
779 -- Qualified expressions may be nested
781 Agg := Original_Node (Expression (Return_Con));
782 while Nkind (Agg) = N_Qualified_Expression loop
783 Agg := Original_Node (Expression (Agg));
786 -- If we are looking at an aggregate instead of a function call we
787 -- can continue checking accessibility for the supplied
788 -- discriminant associations.
790 if Nkind (Agg) = N_Aggregate then
791 if Present (Expressions (Agg)) then
792 Assoc := First (Expressions (Agg));
793 Process_Exprs := True;
795 Assoc := First (Component_Associations (Agg));
798 -- Otherwise the expression is not of interest ???
805 -- Move through the discriminants checking the accessibility level
806 -- of each co-extension's associated expression.
808 Discr := First_Discriminant (R_Type);
809 while Present (Discr) loop
810 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
812 if Nkind (Assoc) = N_Attribute_Reference then
814 elsif Nkind_In (Assoc, N_Component_Association,
815 N_Discriminant_Association)
817 Expr := Expression (Assoc);
822 -- This anonymous access discriminant has an associated
823 -- expression which needs checking.
826 and then Nkind (Expr) = N_Attribute_Reference
827 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
829 -- Obtain the object to perform static checks on by moving
830 -- up the prefixes in the expression taking into account
831 -- named access types and renamed objects within the
834 Obj := Original_Node (Prefix (Expr));
836 while Nkind_In (Obj, N_Explicit_Dereference,
838 N_Selected_Component)
840 -- When we encounter a named access type then we can
841 -- ignore accessibility checks on the dereference.
843 if Ekind (Etype (Original_Node (Prefix (Obj))))
845 E_Access_Protected_Subprogram_Type
847 if Nkind (Obj) = N_Selected_Component then
848 Obj := Selector_Name (Obj);
850 Obj := Original_Node (Prefix (Obj));
855 Obj := Original_Node (Prefix (Obj));
858 if Nkind (Obj) = N_Selected_Component then
859 Obj := Selector_Name (Obj);
862 -- Check for renamings
864 pragma Assert (Is_Entity_Name (Obj));
866 if Present (Renamed_Object (Entity (Obj))) then
867 Obj := Renamed_Object (Entity (Obj));
873 -- Do not check aliased formals or function calls. A
874 -- run-time check may still be needed ???
876 if Is_Formal (Entity (Obj))
877 and then Is_Aliased (Entity (Obj))
881 elsif Object_Access_Level (Obj) >
882 Scope_Depth (Scope (Scope_Id))
885 ("access discriminant in return aggregate would "
886 & "be a dangling reference", Obj);
891 Next_Discriminant (Discr);
893 if not Is_List_Member (Assoc) then
899 -- After aggregate expressions, examine component associations if
904 and then Process_Exprs
905 and then Present (Component_Associations (Agg))
907 Assoc := First (Component_Associations (Agg));
908 Process_Exprs := False;
914 end Check_Return_Construct_Accessibility;
916 -------------------------------------
917 -- Check_Return_Subtype_Indication --
918 -------------------------------------
920 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
921 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
923 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
924 -- Subtype given in the extended return statement (must match R_Type)
926 Subtype_Ind : constant Node_Id :=
927 Object_Definition (Original_Node (Obj_Decl));
929 procedure Error_No_Match (N : Node_Id);
930 -- Output error messages for case where types do not statically
931 -- match. N is the location for the messages.
937 procedure Error_No_Match (N : Node_Id) is
940 ("subtype must statically match function result subtype", N);
942 if not Predicates_Match (R_Stm_Type, R_Type) then
943 Error_Msg_Node_2 := R_Type;
945 ("\predicate of& does not match predicate of&",
950 -- Start of processing for Check_Return_Subtype_Indication
953 -- First, avoid cascaded errors
955 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
959 -- "return access T" case; check that the return statement also has
960 -- "access T", and that the subtypes statically match:
961 -- if this is an access to subprogram the signatures must match.
963 if Is_Anonymous_Access_Type (R_Type) then
964 if Is_Anonymous_Access_Type (R_Stm_Type) then
965 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
967 if Base_Type (Designated_Type (R_Stm_Type)) /=
968 Base_Type (Designated_Type (R_Type))
969 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
971 Error_No_Match (Subtype_Mark (Subtype_Ind));
975 -- For two anonymous access to subprogram types, the types
976 -- themselves must be type conformant.
978 if not Conforming_Types
979 (R_Stm_Type, R_Type, Fully_Conformant)
981 Error_No_Match (Subtype_Ind);
986 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
989 -- If the return object is of an anonymous access type, then report
990 -- an error if the function's result type is not also anonymous.
992 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
993 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
995 ("anonymous access not allowed for function with named access "
996 & "result", Subtype_Ind);
998 -- Subtype indication case: check that the return object's type is
999 -- covered by the result type, and that the subtypes statically match
1000 -- when the result subtype is constrained. Also handle record types
1001 -- with unknown discriminants for which we have built the underlying
1002 -- record view. Coverage is needed to allow specific-type return
1003 -- objects when the result type is class-wide (see AI05-32).
1005 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
1006 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1009 (Base_Type (R_Type),
1010 Underlying_Record_View (Base_Type (R_Stm_Type))))
1012 -- A null exclusion may be present on the return type, on the
1013 -- function specification, on the object declaration or on the
1016 if Is_Access_Type (R_Type)
1018 (Can_Never_Be_Null (R_Type)
1019 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1020 Can_Never_Be_Null (R_Stm_Type)
1022 Error_No_Match (Subtype_Ind);
1025 -- AI05-103: for elementary types, subtypes must statically match
1027 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1028 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1029 Error_No_Match (Subtype_Ind);
1033 -- All remaining cases are illegal
1035 -- Note: previous versions of this subprogram allowed the return
1036 -- value to be the ancestor of the return type if the return type
1037 -- was a null extension. This was plainly incorrect.
1041 ("wrong type for return_subtype_indication", Subtype_Ind);
1043 end Check_Return_Subtype_Indication;
1045 ---------------------
1046 -- Local Variables --
1047 ---------------------
1050 Obj_Decl : Node_Id := Empty;
1052 -- Start of processing for Analyze_Function_Return
1055 Set_Return_Present (Scope_Id);
1057 if Nkind (N) = N_Simple_Return_Statement then
1058 Expr := Expression (N);
1060 -- Guard against a malformed expression. The parser may have tried to
1061 -- recover but the node is not analyzable.
1063 if Nkind (Expr) = N_Error then
1064 Set_Etype (Expr, Any_Type);
1065 Expander_Mode_Save_And_Set (False);
1069 -- The resolution of a controlled [extension] aggregate associated
1070 -- with a return statement creates a temporary which needs to be
1071 -- finalized on function exit. Wrap the return statement inside a
1072 -- block so that the finalization machinery can detect this case.
1073 -- This early expansion is done only when the return statement is
1074 -- not part of a handled sequence of statements.
1076 if Nkind_In (Expr, N_Aggregate,
1077 N_Extension_Aggregate)
1078 and then Needs_Finalization (R_Type)
1079 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1082 Make_Block_Statement (Loc,
1083 Handled_Statement_Sequence =>
1084 Make_Handled_Sequence_Of_Statements (Loc,
1085 Statements => New_List (Relocate_Node (N)))));
1093 -- Ada 2005 (AI-251): If the type of the returned object is
1094 -- an access to an interface type then we add an implicit type
1095 -- conversion to force the displacement of the "this" pointer to
1096 -- reference the secondary dispatch table. We cannot delay the
1097 -- generation of this implicit conversion until the expansion
1098 -- because in this case the type resolution changes the decoration
1099 -- of the expression node to match R_Type; by contrast, if the
1100 -- returned object is a class-wide interface type then it is too
1101 -- early to generate here the implicit conversion since the return
1102 -- statement may be rewritten by the expander into an extended
1103 -- return statement whose expansion takes care of adding the
1104 -- implicit type conversion to displace the pointer to the object.
1107 and then Serious_Errors_Detected = 0
1108 and then Is_Access_Type (R_Type)
1109 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1110 and then Is_Interface (Designated_Type (R_Type))
1111 and then Is_Progenitor (Designated_Type (R_Type),
1112 Designated_Type (Etype (Expr)))
1114 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1118 Resolve (Expr, R_Type);
1119 Check_Limited_Return (N, Expr, R_Type);
1121 Check_Return_Construct_Accessibility (N);
1124 Obj_Decl := Last (Return_Object_Declarations (N));
1126 -- Analyze parts specific to extended_return_statement:
1129 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1130 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1133 Expr := Expression (Obj_Decl);
1135 -- Note: The check for OK_For_Limited_Init will happen in
1136 -- Analyze_Object_Declaration; we treat it as a normal
1137 -- object declaration.
1139 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1142 Check_Return_Subtype_Indication (Obj_Decl);
1144 if Present (HSS) then
1147 if Present (Exception_Handlers (HSS)) then
1149 -- ???Has_Nested_Block_With_Handler needs to be set.
1150 -- Probably by creating an actual N_Block_Statement.
1151 -- Probably in Expand.
1157 -- Mark the return object as referenced, since the return is an
1158 -- implicit reference of the object.
1160 Set_Referenced (Defining_Identifier (Obj_Decl));
1162 Check_References (Stm_Entity);
1164 Check_Return_Construct_Accessibility (N);
1166 -- Check RM 6.5 (5.9/3)
1169 if Ada_Version < Ada_2012 then
1171 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1172 -- Can it really happen (extended return???)
1175 ("aliased only allowed for limited return objects "
1176 & "in Ada 2012??", N);
1178 elsif not Is_Limited_View (R_Type) then
1180 ("aliased only allowed for limited return objects", N);
1186 -- Case of Expr present
1188 if Present (Expr) then
1190 -- Defend against previous errors
1192 if Nkind (Expr) = N_Empty
1193 or else No (Etype (Expr))
1198 -- Apply constraint check. Note that this is done before the implicit
1199 -- conversion of the expression done for anonymous access types to
1200 -- ensure correct generation of the null-excluding check associated
1201 -- with null-excluding expressions found in return statements. We
1202 -- don't need a check if the subtype of the return object is the
1203 -- same as the result subtype of the function.
1205 if Nkind (N) /= N_Extended_Return_Statement
1206 or else Nkind (Obj_Decl) /= N_Object_Declaration
1207 or else Nkind (Object_Definition (Obj_Decl)) not in N_Has_Entity
1208 or else Entity (Object_Definition (Obj_Decl)) /= R_Type
1210 Apply_Constraint_Check (Expr, R_Type);
1213 -- The return value is converted to the return type of the function,
1214 -- which implies a predicate check if the return type is predicated.
1215 -- We do not apply the check to a case expression because it will
1216 -- be expanded into a series of return statements, each of which
1217 -- will receive a predicate check.
1219 if Nkind (Expr) /= N_Case_Expression then
1220 Apply_Predicate_Check (Expr, R_Type);
1223 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1224 -- type, apply an implicit conversion of the expression to that type
1225 -- to force appropriate static and run-time accessibility checks.
1227 if Ada_Version >= Ada_2005
1228 and then Ekind (R_Type) = E_Anonymous_Access_Type
1230 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1231 Analyze_And_Resolve (Expr, R_Type);
1233 -- If this is a local anonymous access to subprogram, the
1234 -- accessibility check can be applied statically. The return is
1235 -- illegal if the access type of the return expression is declared
1236 -- inside of the subprogram (except if it is the subtype indication
1237 -- of an extended return statement).
1239 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1240 if not Comes_From_Source (Current_Scope)
1241 or else Ekind (Current_Scope) = E_Return_Statement
1246 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1248 Error_Msg_N ("cannot return local access to subprogram", N);
1251 -- The expression cannot be of a formal incomplete type
1253 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1254 and then Is_Generic_Type (Etype (Expr))
1257 ("cannot return expression of a formal incomplete type", N);
1260 -- If the result type is class-wide, then check that the return
1261 -- expression's type is not declared at a deeper level than the
1262 -- function (RM05-6.5(5.6/2)).
1264 if Ada_Version >= Ada_2005
1265 and then Is_Class_Wide_Type (R_Type)
1267 if Type_Access_Level (Etype (Expr)) >
1268 Subprogram_Access_Level (Scope_Id)
1271 ("level of return expression type is deeper than "
1272 & "class-wide function!", Expr);
1276 -- Check incorrect use of dynamically tagged expression
1278 if Is_Tagged_Type (R_Type) then
1279 Check_Dynamically_Tagged_Expression
1285 -- ??? A real run-time accessibility check is needed in cases
1286 -- involving dereferences of access parameters. For now we just
1287 -- check the static cases.
1289 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1290 and then Is_Limited_View (Etype (Scope_Id))
1291 and then Object_Access_Level (Expr) >
1292 Subprogram_Access_Level (Scope_Id)
1294 -- Suppress the message in a generic, where the rewriting
1297 if Inside_A_Generic then
1302 Make_Raise_Program_Error (Loc,
1303 Reason => PE_Accessibility_Check_Failed));
1306 Error_Msg_Warn := SPARK_Mode /= On;
1307 Error_Msg_N ("cannot return a local value by reference<<", N);
1308 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1312 if Known_Null (Expr)
1313 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1314 and then Null_Exclusion_Present (Parent (Scope_Id))
1316 Apply_Compile_Time_Constraint_Error
1318 Msg => "(Ada 2005) null not allowed for "
1319 & "null-excluding return??",
1320 Reason => CE_Null_Not_Allowed);
1323 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1324 -- has no initializing expression.
1326 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1327 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1328 Subprogram_Access_Level (Scope_Id)
1331 ("level of return expression type is deeper than "
1332 & "class-wide function!", Obj_Decl);
1335 end Analyze_Function_Return;
1337 -------------------------------------
1338 -- Analyze_Generic_Subprogram_Body --
1339 -------------------------------------
1341 procedure Analyze_Generic_Subprogram_Body
1345 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1346 Kind : constant Entity_Kind := Ekind (Gen_Id);
1347 Body_Id : Entity_Id;
1352 -- Copy body and disable expansion while analyzing the generic For a
1353 -- stub, do not copy the stub (which would load the proper body), this
1354 -- will be done when the proper body is analyzed.
1356 if Nkind (N) /= N_Subprogram_Body_Stub then
1357 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1360 -- Once the contents of the generic copy and the template are
1361 -- swapped, do the same for their respective aspect specifications.
1363 Exchange_Aspects (N, New_N);
1365 -- Collect all contract-related source pragmas found within the
1366 -- template and attach them to the contract of the subprogram body.
1367 -- This contract is used in the capture of global references within
1370 Create_Generic_Contract (N);
1375 Spec := Specification (N);
1377 -- Within the body of the generic, the subprogram is callable, and
1378 -- behaves like the corresponding non-generic unit.
1380 Body_Id := Defining_Entity (Spec);
1382 if Kind = E_Generic_Procedure
1383 and then Nkind (Spec) /= N_Procedure_Specification
1385 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1388 elsif Kind = E_Generic_Function
1389 and then Nkind (Spec) /= N_Function_Specification
1391 Error_Msg_N ("invalid body for generic function ", Body_Id);
1395 Set_Corresponding_Body (Gen_Decl, Body_Id);
1397 if Has_Completion (Gen_Id)
1398 and then Nkind (Parent (N)) /= N_Subunit
1400 Error_Msg_N ("duplicate generic body", N);
1403 Set_Has_Completion (Gen_Id);
1406 if Nkind (N) = N_Subprogram_Body_Stub then
1407 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1409 Set_Corresponding_Spec (N, Gen_Id);
1412 if Nkind (Parent (N)) = N_Compilation_Unit then
1413 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1416 -- Make generic parameters immediately visible in the body. They are
1417 -- needed to process the formals declarations. Then make the formals
1418 -- visible in a separate step.
1420 Push_Scope (Gen_Id);
1424 First_Ent : Entity_Id;
1427 First_Ent := First_Entity (Gen_Id);
1430 while Present (E) and then not Is_Formal (E) loop
1435 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1437 -- Now generic formals are visible, and the specification can be
1438 -- analyzed, for subsequent conformance check.
1440 Body_Id := Analyze_Subprogram_Specification (Spec);
1442 -- Make formal parameters visible
1446 -- E is the first formal parameter, we loop through the formals
1447 -- installing them so that they will be visible.
1449 Set_First_Entity (Gen_Id, E);
1450 while Present (E) loop
1456 -- Visible generic entity is callable within its own body
1458 Set_Ekind (Gen_Id, Ekind (Body_Id));
1459 Set_Ekind (Body_Id, E_Subprogram_Body);
1460 Set_Convention (Body_Id, Convention (Gen_Id));
1461 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1462 Set_Scope (Body_Id, Scope (Gen_Id));
1464 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1466 if Nkind (N) = N_Subprogram_Body_Stub then
1468 -- No body to analyze, so restore state of generic unit
1470 Set_Ekind (Gen_Id, Kind);
1471 Set_Ekind (Body_Id, Kind);
1473 if Present (First_Ent) then
1474 Set_First_Entity (Gen_Id, First_Ent);
1481 -- If this is a compilation unit, it must be made visible explicitly,
1482 -- because the compilation of the declaration, unlike other library
1483 -- unit declarations, does not. If it is not a unit, the following
1484 -- is redundant but harmless.
1486 Set_Is_Immediately_Visible (Gen_Id);
1487 Reference_Body_Formals (Gen_Id, Body_Id);
1489 if Is_Child_Unit (Gen_Id) then
1490 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1493 Set_Actual_Subtypes (N, Current_Scope);
1495 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1496 Set_SPARK_Pragma_Inherited (Body_Id);
1498 -- Analyze any aspect specifications that appear on the generic
1501 if Has_Aspects (N) then
1502 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1505 Analyze_Declarations (Declarations (N));
1508 -- Process the contract of the subprogram body after all declarations
1509 -- have been analyzed. This ensures that any contract-related pragmas
1510 -- are available through the N_Contract node of the body.
1512 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1514 Analyze (Handled_Statement_Sequence (N));
1515 Save_Global_References (Original_Node (N));
1517 -- Prior to exiting the scope, include generic formals again (if any
1518 -- are present) in the set of local entities.
1520 if Present (First_Ent) then
1521 Set_First_Entity (Gen_Id, First_Ent);
1524 Check_References (Gen_Id);
1527 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1528 Update_Use_Clause_Chain;
1529 Validate_Categorization_Dependency (N, Gen_Id);
1531 Check_Subprogram_Order (N);
1533 -- Outside of its body, unit is generic again
1535 Set_Ekind (Gen_Id, Kind);
1536 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1539 Style.Check_Identifier (Body_Id, Gen_Id);
1543 end Analyze_Generic_Subprogram_Body;
1545 ----------------------------
1546 -- Analyze_Null_Procedure --
1547 ----------------------------
1549 -- WARNING: This routine manages Ghost regions. Return statements must be
1550 -- replaced by gotos that jump to the end of the routine and restore the
1553 procedure Analyze_Null_Procedure
1555 Is_Completion : out Boolean)
1557 Loc : constant Source_Ptr := Sloc (N);
1558 Spec : constant Node_Id := Specification (N);
1560 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1561 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1562 Saved_ISMP : constant Boolean :=
1563 Ignore_SPARK_Mode_Pragmas_In_Instance;
1564 -- Save the Ghost and SPARK mode-related data to restore on exit
1566 Designator : Entity_Id;
1568 Null_Body : Node_Id := Empty;
1569 Null_Stmt : Node_Id := Null_Statement (Spec);
1573 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1575 -- A null procedure is Ghost when it is stand-alone and is subject to
1576 -- pragma Ghost, or when the corresponding spec is Ghost. Set the mode
1577 -- now, to ensure that any nodes generated during analysis and expansion
1578 -- are properly marked as Ghost.
1580 if Present (Prev) then
1581 Mark_And_Set_Ghost_Body (N, Prev);
1584 -- Capture the profile of the null procedure before analysis, for
1585 -- expansion at the freeze point and at each point of call. The body is
1586 -- used if the procedure has preconditions, or if it is a completion. In
1587 -- the first case the body is analyzed at the freeze point, in the other
1588 -- it replaces the null procedure declaration.
1590 -- For a null procedure that comes from source, a NULL statement is
1591 -- provided by the parser, which carries the source location of the
1592 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1593 -- from expansion, create one now.
1595 if No (Null_Stmt) then
1596 Null_Stmt := Make_Null_Statement (Loc);
1600 Make_Subprogram_Body (Loc,
1601 Specification => New_Copy_Tree (Spec),
1602 Declarations => New_List,
1603 Handled_Statement_Sequence =>
1604 Make_Handled_Sequence_Of_Statements (Loc,
1605 Statements => New_List (Null_Stmt)));
1607 -- Create new entities for body and formals
1609 Set_Defining_Unit_Name (Specification (Null_Body),
1610 Make_Defining_Identifier
1611 (Sloc (Defining_Entity (N)),
1612 Chars (Defining_Entity (N))));
1614 Form := First (Parameter_Specifications (Specification (Null_Body)));
1615 while Present (Form) loop
1616 Set_Defining_Identifier (Form,
1617 Make_Defining_Identifier
1618 (Sloc (Defining_Identifier (Form)),
1619 Chars (Defining_Identifier (Form))));
1623 -- Determine whether the null procedure may be a completion of a generic
1624 -- suprogram, in which case we use the new null body as the completion
1625 -- and set minimal semantic information on the original declaration,
1626 -- which is rewritten as a null statement.
1628 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1629 Insert_Before (N, Null_Body);
1630 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1632 Rewrite (N, Make_Null_Statement (Loc));
1633 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1634 Is_Completion := True;
1639 -- Resolve the types of the formals now, because the freeze point may
1640 -- appear in a different context, e.g. an instantiation.
1642 Form := First (Parameter_Specifications (Specification (Null_Body)));
1643 while Present (Form) loop
1644 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1645 Find_Type (Parameter_Type (Form));
1647 elsif No (Access_To_Subprogram_Definition
1648 (Parameter_Type (Form)))
1650 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1652 -- The case of a null procedure with a formal that is an
1653 -- access-to-subprogram type, and that is used as an actual
1654 -- in an instantiation is left to the enthusiastic reader.
1664 -- If there are previous overloadable entities with the same name, check
1665 -- whether any of them is completed by the null procedure.
1667 if Present (Prev) and then Is_Overloadable (Prev) then
1668 Designator := Analyze_Subprogram_Specification (Spec);
1669 Prev := Find_Corresponding_Spec (N);
1672 if No (Prev) or else not Comes_From_Source (Prev) then
1673 Designator := Analyze_Subprogram_Specification (Spec);
1674 Set_Has_Completion (Designator);
1676 -- Signal to caller that this is a procedure declaration
1678 Is_Completion := False;
1680 -- Null procedures are always inlined, but generic formal subprograms
1681 -- which appear as such in the internal instance of formal packages,
1682 -- need no completion and are not marked Inline.
1685 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1687 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1688 Set_Body_To_Inline (N, Null_Body);
1689 Set_Is_Inlined (Designator);
1693 -- The null procedure is a completion. We unconditionally rewrite
1694 -- this as a null body (even if expansion is not active), because
1695 -- there are various error checks that are applied on this body
1696 -- when it is analyzed (e.g. correct aspect placement).
1698 if Has_Completion (Prev) then
1699 Error_Msg_Sloc := Sloc (Prev);
1700 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1703 Check_Previous_Null_Procedure (N, Prev);
1705 Is_Completion := True;
1706 Rewrite (N, Null_Body);
1711 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
1712 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1713 end Analyze_Null_Procedure;
1715 -----------------------------
1716 -- Analyze_Operator_Symbol --
1717 -----------------------------
1719 -- An operator symbol such as "+" or "and" may appear in context where the
1720 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1721 -- is just a string, as in (conjunction = "or"). In these cases the parser
1722 -- generates this node, and the semantics does the disambiguation. Other
1723 -- such case are actuals in an instantiation, the generic unit in an
1724 -- instantiation, and pragma arguments.
1726 procedure Analyze_Operator_Symbol (N : Node_Id) is
1727 Par : constant Node_Id := Parent (N);
1730 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1731 or else Nkind (Par) = N_Function_Instantiation
1732 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1733 or else (Nkind (Par) = N_Pragma_Argument_Association
1734 and then not Is_Pragma_String_Literal (Par))
1735 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1736 or else (Nkind (Par) = N_Attribute_Reference
1737 and then Attribute_Name (Par) /= Name_Value)
1739 Find_Direct_Name (N);
1742 Change_Operator_Symbol_To_String_Literal (N);
1745 end Analyze_Operator_Symbol;
1747 -----------------------------------
1748 -- Analyze_Parameter_Association --
1749 -----------------------------------
1751 procedure Analyze_Parameter_Association (N : Node_Id) is
1753 Analyze (Explicit_Actual_Parameter (N));
1754 end Analyze_Parameter_Association;
1756 ----------------------------
1757 -- Analyze_Procedure_Call --
1758 ----------------------------
1760 -- WARNING: This routine manages Ghost regions. Return statements must be
1761 -- replaced by gotos that jump to the end of the routine and restore the
1764 procedure Analyze_Procedure_Call (N : Node_Id) is
1765 procedure Analyze_Call_And_Resolve;
1766 -- Do Analyze and Resolve calls for procedure call. At the end, check
1767 -- for illegal order dependence.
1768 -- ??? where is the check for illegal order dependencies?
1770 ------------------------------
1771 -- Analyze_Call_And_Resolve --
1772 ------------------------------
1774 procedure Analyze_Call_And_Resolve is
1776 if Nkind (N) = N_Procedure_Call_Statement then
1778 Resolve (N, Standard_Void_Type);
1782 end Analyze_Call_And_Resolve;
1786 Actuals : constant List_Id := Parameter_Associations (N);
1787 Loc : constant Source_Ptr := Sloc (N);
1788 P : constant Node_Id := Name (N);
1790 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1791 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1792 -- Save the Ghost-related attributes to restore on exit
1797 -- Start of processing for Analyze_Procedure_Call
1800 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1801 -- a procedure call or an entry call. The prefix may denote an access
1802 -- to subprogram type, in which case an implicit dereference applies.
1803 -- If the prefix is an indexed component (without implicit dereference)
1804 -- then the construct denotes a call to a member of an entire family.
1805 -- If the prefix is a simple name, it may still denote a call to a
1806 -- parameterless member of an entry family. Resolution of these various
1807 -- interpretations is delicate.
1809 -- Do not analyze machine code statements to avoid rejecting them in
1812 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1813 Set_Etype (P, Standard_Void_Type);
1818 -- If this is a call of the form Obj.Op, the call may have been analyzed
1819 -- and possibly rewritten into a block, in which case we are done.
1821 if Analyzed (N) then
1824 -- If there is an error analyzing the name (which may have been
1825 -- rewritten if the original call was in prefix notation) then error
1826 -- has been emitted already, mark node and return.
1828 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1829 Set_Etype (N, Any_Type);
1833 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1834 -- Set the mode now to ensure that any nodes generated during analysis
1835 -- and expansion are properly marked as Ghost.
1837 Mark_And_Set_Ghost_Procedure_Call (N);
1839 -- Otherwise analyze the parameters
1841 if Present (Actuals) then
1842 Actual := First (Actuals);
1844 while Present (Actual) loop
1846 Check_Parameterless_Call (Actual);
1851 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1853 if Nkind (P) = N_Attribute_Reference
1854 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1856 Name_Elab_Subp_Body)
1858 if Present (Actuals) then
1860 ("no parameters allowed for this call", First (Actuals));
1864 Set_Etype (N, Standard_Void_Type);
1867 elsif Is_Entity_Name (P)
1868 and then Is_Record_Type (Etype (Entity (P)))
1869 and then Remote_AST_I_Dereference (P)
1873 elsif Is_Entity_Name (P)
1874 and then Ekind (Entity (P)) /= E_Entry_Family
1876 if Is_Access_Type (Etype (P))
1877 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1878 and then No (Actuals)
1879 and then Comes_From_Source (N)
1881 Error_Msg_N ("missing explicit dereference in call", N);
1884 Analyze_Call_And_Resolve;
1886 -- If the prefix is the simple name of an entry family, this is a
1887 -- parameterless call from within the task body itself.
1889 elsif Is_Entity_Name (P)
1890 and then Nkind (P) = N_Identifier
1891 and then Ekind (Entity (P)) = E_Entry_Family
1892 and then Present (Actuals)
1893 and then No (Next (First (Actuals)))
1895 -- Can be call to parameterless entry family. What appears to be the
1896 -- sole argument is in fact the entry index. Rewrite prefix of node
1897 -- accordingly. Source representation is unchanged by this
1901 Make_Indexed_Component (Loc,
1903 Make_Selected_Component (Loc,
1904 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1905 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1906 Expressions => Actuals);
1907 Set_Name (N, New_N);
1908 Set_Etype (New_N, Standard_Void_Type);
1909 Set_Parameter_Associations (N, No_List);
1910 Analyze_Call_And_Resolve;
1912 elsif Nkind (P) = N_Explicit_Dereference then
1913 if Ekind (Etype (P)) = E_Subprogram_Type then
1914 Analyze_Call_And_Resolve;
1916 Error_Msg_N ("expect access to procedure in call", P);
1919 -- The name can be a selected component or an indexed component that
1920 -- yields an access to subprogram. Such a prefix is legal if the call
1921 -- has parameter associations.
1923 elsif Is_Access_Type (Etype (P))
1924 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1926 if Present (Actuals) then
1927 Analyze_Call_And_Resolve;
1929 Error_Msg_N ("missing explicit dereference in call ", N);
1932 -- If not an access to subprogram, then the prefix must resolve to the
1933 -- name of an entry, entry family, or protected operation.
1935 -- For the case of a simple entry call, P is a selected component where
1936 -- the prefix is the task and the selector name is the entry. A call to
1937 -- a protected procedure will have the same syntax. If the protected
1938 -- object contains overloaded operations, the entity may appear as a
1939 -- function, the context will select the operation whose type is Void.
1941 elsif Nkind (P) = N_Selected_Component
1942 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1946 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1947 -- in prefix notation may still be missing its controlling argument,
1948 -- so perform the transformation now.
1950 if SPARK_Mode = On and then In_Inlined_Body then
1952 Subp : constant Entity_Id := Entity (Selector_Name (P));
1953 Typ : constant Entity_Id := Etype (Prefix (P));
1956 if Is_Tagged_Type (Typ)
1957 and then Present (First_Formal (Subp))
1958 and then (Etype (First_Formal (Subp)) = Typ
1960 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1961 and then Try_Object_Operation (P)
1966 Analyze_Call_And_Resolve;
1971 Analyze_Call_And_Resolve;
1974 elsif Nkind (P) = N_Selected_Component
1975 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1976 and then Present (Actuals)
1977 and then No (Next (First (Actuals)))
1979 -- Can be call to parameterless entry family. What appears to be the
1980 -- sole argument is in fact the entry index. Rewrite prefix of node
1981 -- accordingly. Source representation is unchanged by this
1985 Make_Indexed_Component (Loc,
1986 Prefix => New_Copy (P),
1987 Expressions => Actuals);
1988 Set_Name (N, New_N);
1989 Set_Etype (New_N, Standard_Void_Type);
1990 Set_Parameter_Associations (N, No_List);
1991 Analyze_Call_And_Resolve;
1993 -- For the case of a reference to an element of an entry family, P is
1994 -- an indexed component whose prefix is a selected component (task and
1995 -- entry family), and whose index is the entry family index.
1997 elsif Nkind (P) = N_Indexed_Component
1998 and then Nkind (Prefix (P)) = N_Selected_Component
1999 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
2001 Analyze_Call_And_Resolve;
2003 -- If the prefix is the name of an entry family, it is a call from
2004 -- within the task body itself.
2006 elsif Nkind (P) = N_Indexed_Component
2007 and then Nkind (Prefix (P)) = N_Identifier
2008 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
2011 Make_Selected_Component (Loc,
2013 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
2014 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
2015 Rewrite (Prefix (P), New_N);
2017 Analyze_Call_And_Resolve;
2019 -- In Ada 2012. a qualified expression is a name, but it cannot be a
2020 -- procedure name, so the construct can only be a qualified expression.
2022 elsif Nkind (P) = N_Qualified_Expression
2023 and then Ada_Version >= Ada_2012
2025 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
2028 -- Anything else is an error
2031 Error_Msg_N ("invalid procedure or entry call", N);
2035 Restore_Ghost_Region (Saved_GM, Saved_IGR);
2036 end Analyze_Procedure_Call;
2038 ------------------------------
2039 -- Analyze_Return_Statement --
2040 ------------------------------
2042 procedure Analyze_Return_Statement (N : Node_Id) is
2043 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2044 N_Simple_Return_Statement));
2046 Returns_Object : constant Boolean :=
2047 Nkind (N) = N_Extended_Return_Statement
2049 (Nkind (N) = N_Simple_Return_Statement
2050 and then Present (Expression (N)));
2051 -- True if we're returning something; that is, "return <expression>;"
2052 -- or "return Result : T [:= ...]". False for "return;". Used for error
2053 -- checking: If Returns_Object is True, N should apply to a function
2054 -- body; otherwise N should apply to a procedure body, entry body,
2055 -- accept statement, or extended return statement.
2057 function Find_What_It_Applies_To return Entity_Id;
2058 -- Find the entity representing the innermost enclosing body, accept
2059 -- statement, or extended return statement. If the result is a callable
2060 -- construct or extended return statement, then this will be the value
2061 -- of the Return_Applies_To attribute. Otherwise, the program is
2062 -- illegal. See RM-6.5(4/2).
2064 -----------------------------
2065 -- Find_What_It_Applies_To --
2066 -----------------------------
2068 function Find_What_It_Applies_To return Entity_Id is
2069 Result : Entity_Id := Empty;
2072 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2073 -- and postconditions.
2075 for J in reverse 0 .. Scope_Stack.Last loop
2076 Result := Scope_Stack.Table (J).Entity;
2077 exit when not Ekind_In (Result, E_Block, E_Loop)
2078 and then Chars (Result) /= Name_uPostconditions;
2081 pragma Assert (Present (Result));
2083 end Find_What_It_Applies_To;
2085 -- Local declarations
2087 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2088 Kind : constant Entity_Kind := Ekind (Scope_Id);
2089 Loc : constant Source_Ptr := Sloc (N);
2090 Stm_Entity : constant Entity_Id :=
2092 (E_Return_Statement, Current_Scope, Loc, 'R');
2094 -- Start of processing for Analyze_Return_Statement
2097 Set_Return_Statement_Entity (N, Stm_Entity);
2099 Set_Etype (Stm_Entity, Standard_Void_Type);
2100 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2102 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2103 -- (4/2): an inner return statement will apply to this extended return.
2105 if Nkind (N) = N_Extended_Return_Statement then
2106 Push_Scope (Stm_Entity);
2109 -- Check that pragma No_Return is obeyed. Don't complain about the
2110 -- implicitly-generated return that is placed at the end.
2112 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2113 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2116 -- Warn on any unassigned OUT parameters if in procedure
2118 if Ekind (Scope_Id) = E_Procedure then
2119 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2122 -- Check that functions return objects, and other things do not
2124 if Kind = E_Function or else Kind = E_Generic_Function then
2125 if not Returns_Object then
2126 Error_Msg_N ("missing expression in return from function", N);
2129 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2130 if Returns_Object then
2131 Error_Msg_N ("procedure cannot return value (use function)", N);
2134 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2135 if Returns_Object then
2136 if Is_Protected_Type (Scope (Scope_Id)) then
2137 Error_Msg_N ("entry body cannot return value", N);
2139 Error_Msg_N ("accept statement cannot return value", N);
2143 elsif Kind = E_Return_Statement then
2145 -- We are nested within another return statement, which must be an
2146 -- extended_return_statement.
2148 if Returns_Object then
2149 if Nkind (N) = N_Extended_Return_Statement then
2151 ("extended return statement cannot be nested (use `RETURN;`)",
2154 -- Case of a simple return statement with a value inside extended
2155 -- return statement.
2159 ("return nested in extended return statement cannot return "
2160 & "value (use `RETURN;`)", N);
2165 Error_Msg_N ("illegal context for return statement", N);
2168 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2169 Analyze_Function_Return (N);
2171 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2172 Set_Return_Present (Scope_Id);
2175 if Nkind (N) = N_Extended_Return_Statement then
2179 Kill_Current_Values (Last_Assignment_Only => True);
2180 Check_Unreachable_Code (N);
2182 Analyze_Dimension (N);
2183 end Analyze_Return_Statement;
2185 -------------------------------------
2186 -- Analyze_Simple_Return_Statement --
2187 -------------------------------------
2189 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2191 if Present (Expression (N)) then
2192 Mark_Coextensions (N, Expression (N));
2195 Analyze_Return_Statement (N);
2196 end Analyze_Simple_Return_Statement;
2198 -------------------------
2199 -- Analyze_Return_Type --
2200 -------------------------
2202 procedure Analyze_Return_Type (N : Node_Id) is
2203 Designator : constant Entity_Id := Defining_Entity (N);
2204 Typ : Entity_Id := Empty;
2207 -- Normal case where result definition does not indicate an error
2209 if Result_Definition (N) /= Error then
2210 if Nkind (Result_Definition (N)) = N_Access_Definition then
2212 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2215 AD : constant Node_Id :=
2216 Access_To_Subprogram_Definition (Result_Definition (N));
2218 if Present (AD) and then Protected_Present (AD) then
2219 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2221 Typ := Access_Definition (N, Result_Definition (N));
2225 Set_Parent (Typ, Result_Definition (N));
2226 Set_Is_Local_Anonymous_Access (Typ);
2227 Set_Etype (Designator, Typ);
2229 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2231 Null_Exclusion_Static_Checks (N);
2233 -- Subtype_Mark case
2236 Find_Type (Result_Definition (N));
2237 Typ := Entity (Result_Definition (N));
2238 Set_Etype (Designator, Typ);
2240 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2242 Null_Exclusion_Static_Checks (N);
2244 -- If a null exclusion is imposed on the result type, then create
2245 -- a null-excluding itype (an access subtype) and use it as the
2246 -- function's Etype. Note that the null exclusion checks are done
2247 -- right before this, because they don't get applied to types that
2248 -- do not come from source.
2250 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2251 Set_Etype (Designator,
2252 Create_Null_Excluding_Itype
2255 Scope_Id => Scope (Current_Scope)));
2257 -- The new subtype must be elaborated before use because
2258 -- it is visible outside of the function. However its base
2259 -- type may not be frozen yet, so the reference that will
2260 -- force elaboration must be attached to the freezing of
2263 -- If the return specification appears on a proper body,
2264 -- the subtype will have been created already on the spec.
2266 if Is_Frozen (Typ) then
2267 if Nkind (Parent (N)) = N_Subprogram_Body
2268 and then Nkind (Parent (Parent (N))) = N_Subunit
2272 Build_Itype_Reference (Etype (Designator), Parent (N));
2276 Ensure_Freeze_Node (Typ);
2279 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2281 Set_Itype (IR, Etype (Designator));
2282 Append_Freeze_Actions (Typ, New_List (IR));
2287 Set_Etype (Designator, Typ);
2290 if Ekind (Typ) = E_Incomplete_Type
2291 or else (Is_Class_Wide_Type (Typ)
2292 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2294 -- AI05-0151: Tagged incomplete types are allowed in all formal
2295 -- parts. Untagged incomplete types are not allowed in bodies.
2296 -- As a consequence, limited views cannot appear in a basic
2297 -- declaration that is itself within a body, because there is
2298 -- no point at which the non-limited view will become visible.
2300 if Ada_Version >= Ada_2012 then
2301 if From_Limited_With (Typ) and then In_Package_Body then
2303 ("invalid use of incomplete type&",
2304 Result_Definition (N), Typ);
2306 -- The return type of a subprogram body cannot be of a
2307 -- formal incomplete type.
2309 elsif Is_Generic_Type (Typ)
2310 and then Nkind (Parent (N)) = N_Subprogram_Body
2313 ("return type cannot be a formal incomplete type",
2314 Result_Definition (N));
2316 elsif Is_Class_Wide_Type (Typ)
2317 and then Is_Generic_Type (Root_Type (Typ))
2318 and then Nkind (Parent (N)) = N_Subprogram_Body
2321 ("return type cannot be a formal incomplete type",
2322 Result_Definition (N));
2324 elsif Is_Tagged_Type (Typ) then
2327 -- Use is legal in a thunk generated for an operation
2328 -- inherited from a progenitor.
2330 elsif Is_Thunk (Designator)
2331 and then Present (Non_Limited_View (Typ))
2335 elsif Nkind (Parent (N)) = N_Subprogram_Body
2336 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2340 ("invalid use of untagged incomplete type&",
2344 -- The type must be completed in the current package. This
2345 -- is checked at the end of the package declaration when
2346 -- Taft-amendment types are identified. If the return type
2347 -- is class-wide, there is no required check, the type can
2348 -- be a bona fide TAT.
2350 if Ekind (Scope (Current_Scope)) = E_Package
2351 and then In_Private_Part (Scope (Current_Scope))
2352 and then not Is_Class_Wide_Type (Typ)
2354 Append_Elmt (Designator, Private_Dependents (Typ));
2359 ("invalid use of incomplete type&", Designator, Typ);
2364 -- Case where result definition does indicate an error
2367 Set_Etype (Designator, Any_Type);
2369 end Analyze_Return_Type;
2371 -----------------------------
2372 -- Analyze_Subprogram_Body --
2373 -----------------------------
2375 procedure Analyze_Subprogram_Body (N : Node_Id) is
2376 Loc : constant Source_Ptr := Sloc (N);
2377 Body_Spec : constant Node_Id := Specification (N);
2378 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2381 if Debug_Flag_C then
2382 Write_Str ("==> subprogram body ");
2383 Write_Name (Chars (Body_Id));
2384 Write_Str (" from ");
2385 Write_Location (Loc);
2390 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2392 -- The real work is split out into the helper, so it can do "return;"
2393 -- without skipping the debug output:
2395 Analyze_Subprogram_Body_Helper (N);
2397 if Debug_Flag_C then
2399 Write_Str ("<== subprogram body ");
2400 Write_Name (Chars (Body_Id));
2401 Write_Str (" from ");
2402 Write_Location (Loc);
2405 end Analyze_Subprogram_Body;
2407 ------------------------------------
2408 -- Analyze_Subprogram_Body_Helper --
2409 ------------------------------------
2411 -- This procedure is called for regular subprogram bodies, generic bodies,
2412 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2413 -- specification matters, and is used to create a proper declaration for
2414 -- the subprogram, or to perform conformance checks.
2416 -- WARNING: This routine manages Ghost regions. Return statements must be
2417 -- replaced by gotos that jump to the end of the routine and restore the
2420 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2421 Body_Spec : Node_Id := Specification (N);
2422 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2423 Loc : constant Source_Ptr := Sloc (N);
2424 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2426 Conformant : Boolean;
2427 Desig_View : Entity_Id := Empty;
2428 Exch_Views : Elist_Id := No_Elist;
2430 Mask_Types : Elist_Id := No_Elist;
2431 Prot_Typ : Entity_Id := Empty;
2432 Spec_Decl : Node_Id := Empty;
2433 Spec_Id : Entity_Id;
2435 Last_Real_Spec_Entity : Entity_Id := Empty;
2436 -- When we analyze a separate spec, the entity chain ends up containing
2437 -- the formals, as well as any itypes generated during analysis of the
2438 -- default expressions for parameters, or the arguments of associated
2439 -- precondition/postcondition pragmas (which are analyzed in the context
2440 -- of the spec since they have visibility on formals).
2442 -- These entities belong with the spec and not the body. However we do
2443 -- the analysis of the body in the context of the spec (again to obtain
2444 -- visibility to the formals), and all the entities generated during
2445 -- this analysis end up also chained to the entity chain of the spec.
2446 -- But they really belong to the body, and there is circuitry to move
2447 -- them from the spec to the body.
2449 -- However, when we do this move, we don't want to move the real spec
2450 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2451 -- variable points to the last real spec entity, so we only move those
2452 -- chained beyond that point. It is initialized to Empty to deal with
2453 -- the case where there is no separate spec.
2455 function Body_Has_Contract return Boolean;
2456 -- Check whether unanalyzed body has an aspect or pragma that may
2457 -- generate a SPARK contract.
2459 function Body_Has_SPARK_Mode_On return Boolean;
2460 -- Check whether SPARK_Mode On applies to the subprogram body, either
2461 -- because it is specified directly on the body, or because it is
2462 -- inherited from the enclosing subprogram or package.
2464 procedure Build_Subprogram_Declaration;
2465 -- Create a matching subprogram declaration for subprogram body N
2467 procedure Check_Anonymous_Return;
2468 -- Ada 2005: if a function returns an access type that denotes a task,
2469 -- or a type that contains tasks, we must create a master entity for
2470 -- the anonymous type, which typically will be used in an allocator
2471 -- in the body of the function.
2473 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2474 -- Look ahead to recognize a pragma that may appear after the body.
2475 -- If there is a previous spec, check that it appears in the same
2476 -- declarative part. If the pragma is Inline_Always, perform inlining
2477 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2478 -- If the body acts as a spec, and inlining is required, we create a
2479 -- subprogram declaration for it, in order to attach the body to inline.
2480 -- If pragma does not appear after the body, check whether there is
2481 -- an inline pragma before any local declarations.
2483 procedure Check_Missing_Return;
2484 -- Checks for a function with a no return statements, and also performs
2485 -- the warning checks implemented by Check_Returns. In formal mode, also
2486 -- verify that a function ends with a RETURN and that a procedure does
2487 -- not contain any RETURN.
2489 function Disambiguate_Spec return Entity_Id;
2490 -- When a primitive is declared between the private view and the full
2491 -- view of a concurrent type which implements an interface, a special
2492 -- mechanism is used to find the corresponding spec of the primitive
2495 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2496 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2497 -- incomplete types coming from a limited context and replace their
2498 -- limited views with the non-limited ones. Return the list of changes
2499 -- to be used to undo the transformation.
2501 function Is_Private_Concurrent_Primitive
2502 (Subp_Id : Entity_Id) return Boolean;
2503 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2504 -- type that implements an interface and has a private view.
2506 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2507 -- N is the body generated for an expression function that is not a
2508 -- completion and Spec_Id the defining entity of its spec. Mark all
2509 -- the not-yet-frozen types referenced by the simple return statement
2510 -- of the function as formally frozen.
2512 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2513 -- Undo the transformation done by Exchange_Limited_Views.
2515 procedure Set_Trivial_Subprogram (N : Node_Id);
2516 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2517 -- subprogram whose body is being analyzed. N is the statement node
2518 -- causing the flag to be set, if the following statement is a return
2519 -- of an entity, we mark the entity as set in source to suppress any
2520 -- warning on the stylized use of function stubs with a dummy return.
2522 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2523 -- Undo the transformation done by Mask_Unfrozen_Types
2525 procedure Verify_Overriding_Indicator;
2526 -- If there was a previous spec, the entity has been entered in the
2527 -- current scope previously. If the body itself carries an overriding
2528 -- indicator, check that it is consistent with the known status of the
2531 -----------------------
2532 -- Body_Has_Contract --
2533 -----------------------
2535 function Body_Has_Contract return Boolean is
2536 Decls : constant List_Id := Declarations (N);
2540 -- Check for aspects that may generate a contract
2542 if Present (Aspect_Specifications (N)) then
2543 Item := First (Aspect_Specifications (N));
2544 while Present (Item) loop
2545 if Is_Subprogram_Contract_Annotation (Item) then
2553 -- Check for pragmas that may generate a contract
2555 if Present (Decls) then
2556 Item := First (Decls);
2557 while Present (Item) loop
2558 if Nkind (Item) = N_Pragma
2559 and then Is_Subprogram_Contract_Annotation (Item)
2569 end Body_Has_Contract;
2571 ----------------------------
2572 -- Body_Has_SPARK_Mode_On --
2573 ----------------------------
2575 function Body_Has_SPARK_Mode_On return Boolean is
2576 Decls : constant List_Id := Declarations (N);
2580 -- Check for SPARK_Mode aspect
2582 if Present (Aspect_Specifications (N)) then
2583 Item := First (Aspect_Specifications (N));
2584 while Present (Item) loop
2585 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2586 return Get_SPARK_Mode_From_Annotation (Item) = On;
2593 -- Check for SPARK_Mode pragma
2595 if Present (Decls) then
2596 Item := First (Decls);
2597 while Present (Item) loop
2599 -- Pragmas that apply to a subprogram body are usually grouped
2600 -- together. Look for a potential pragma SPARK_Mode among them.
2602 if Nkind (Item) = N_Pragma then
2603 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2604 return Get_SPARK_Mode_From_Annotation (Item) = On;
2607 -- Otherwise the first non-pragma declarative item terminates
2608 -- the region where pragma SPARK_Mode may appear.
2618 -- Otherwise, the applicable SPARK_Mode is inherited from the
2619 -- enclosing subprogram or package.
2621 return SPARK_Mode = On;
2622 end Body_Has_SPARK_Mode_On;
2624 ----------------------------------
2625 -- Build_Subprogram_Declaration --
2626 ----------------------------------
2628 procedure Build_Subprogram_Declaration is
2629 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2630 -- Relocate certain categorization pragmas from the declarative list
2631 -- of subprogram body From and insert them after node To. The pragmas
2634 -- Volatile_Function
2635 -- Also copy pragma SPARK_Mode if present in the declarative list
2636 -- of subprogram body From and insert it after node To. This pragma
2637 -- should not be moved, as it applies to the body too.
2643 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2645 Next_Decl : Node_Id;
2648 pragma Assert (Nkind (From) = N_Subprogram_Body);
2650 -- The destination node must be part of a list, as the pragmas are
2651 -- inserted after it.
2653 pragma Assert (Is_List_Member (To));
2655 -- Inspect the declarations of the subprogram body looking for
2656 -- specific pragmas.
2658 Decl := First (Declarations (N));
2659 while Present (Decl) loop
2660 Next_Decl := Next (Decl);
2662 if Nkind (Decl) = N_Pragma then
2663 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2664 Insert_After (To, New_Copy_Tree (Decl));
2666 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2668 Name_Volatile_Function)
2671 Insert_After (To, Decl);
2682 Subp_Decl : Node_Id;
2684 -- Start of processing for Build_Subprogram_Declaration
2687 -- Create a matching subprogram spec using the profile of the body.
2688 -- The structure of the tree is identical, but has new entities for
2689 -- the defining unit name and formal parameters.
2692 Make_Subprogram_Declaration (Loc,
2693 Specification => Copy_Subprogram_Spec (Body_Spec));
2694 Set_Comes_From_Source (Subp_Decl, True);
2696 -- Also mark parameters as coming from source
2698 if Present (Parameter_Specifications (Specification (Subp_Decl))) then
2703 First (Parameter_Specifications (Specification (Subp_Decl)));
2705 while Present (Form) loop
2706 Set_Comes_From_Source (Defining_Identifier (Form), True);
2712 -- Relocate the aspects and relevant pragmas from the subprogram body
2713 -- to the generated spec because it acts as the initial declaration.
2715 Insert_Before (N, Subp_Decl);
2716 Move_Aspects (N, To => Subp_Decl);
2717 Move_Pragmas (N, To => Subp_Decl);
2719 -- Ensure that the generated corresponding spec and original body
2720 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2721 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2722 -- correctly set for local subprograms.
2724 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2726 Analyze (Subp_Decl);
2728 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2729 -- the body since the expander may generate calls using that entity.
2730 -- Required to ensure that Expand_Call rewrites calls to this
2731 -- function by calls to the built procedure.
2733 if Modify_Tree_For_C
2734 and then Nkind (Body_Spec) = N_Function_Specification
2736 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2738 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2739 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2740 Corresponding_Procedure
2741 (Defining_Entity (Specification (Subp_Decl))));
2744 -- Analyze any relocated source pragmas or pragmas created for aspect
2747 Decl := Next (Subp_Decl);
2748 while Present (Decl) loop
2750 -- Stop the search for pragmas once the body has been reached as
2751 -- this terminates the region where pragmas may appear.
2756 elsif Nkind (Decl) = N_Pragma then
2763 Spec_Id := Defining_Entity (Subp_Decl);
2764 Set_Corresponding_Spec (N, Spec_Id);
2766 -- Mark the generated spec as a source construct to ensure that all
2767 -- calls to it are properly registered in ALI files for GNATprove.
2769 Set_Comes_From_Source (Spec_Id, True);
2771 -- Ensure that the specs of the subprogram declaration and its body
2772 -- are identical, otherwise they will appear non-conformant due to
2773 -- rewritings in the default values of formal parameters.
2775 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2776 Set_Specification (N, Body_Spec);
2777 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2778 end Build_Subprogram_Declaration;
2780 ----------------------------
2781 -- Check_Anonymous_Return --
2782 ----------------------------
2784 procedure Check_Anonymous_Return is
2790 if Present (Spec_Id) then
2796 if Ekind (Scop) = E_Function
2797 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2798 and then not Is_Thunk (Scop)
2800 -- Skip internally built functions which handle the case of
2801 -- a null access (see Expand_Interface_Conversion)
2803 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2804 and then not Comes_From_Source (Parent (Scop)))
2806 and then (Has_Task (Designated_Type (Etype (Scop)))
2808 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2810 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2811 and then Expander_Active
2813 -- Avoid cases with no tasking support
2815 and then RTE_Available (RE_Current_Master)
2816 and then not Restriction_Active (No_Task_Hierarchy)
2819 Make_Object_Declaration (Loc,
2820 Defining_Identifier =>
2821 Make_Defining_Identifier (Loc, Name_uMaster),
2822 Constant_Present => True,
2823 Object_Definition =>
2824 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2826 Make_Explicit_Dereference (Loc,
2827 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2829 if Present (Declarations (N)) then
2830 Prepend (Decl, Declarations (N));
2832 Set_Declarations (N, New_List (Decl));
2835 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2836 Set_Has_Master_Entity (Scop);
2838 -- Now mark the containing scope as a task master
2841 while Nkind (Par) /= N_Compilation_Unit loop
2842 Par := Parent (Par);
2843 pragma Assert (Present (Par));
2845 -- If we fall off the top, we are at the outer level, and
2846 -- the environment task is our effective master, so nothing
2850 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2852 Set_Is_Task_Master (Par, True);
2857 end Check_Anonymous_Return;
2859 -------------------------
2860 -- Check_Inline_Pragma --
2861 -------------------------
2863 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2867 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2868 -- True when N is a pragma Inline or Inline_Always that applies
2869 -- to this subprogram.
2871 -----------------------
2872 -- Is_Inline_Pragma --
2873 -----------------------
2875 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2877 if Nkind (N) = N_Pragma
2879 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2880 or else (Pragma_Name_Unmapped (N) = Name_Inline
2882 (Front_End_Inlining or else Optimization_Level > 0)))
2883 and then Present (Pragma_Argument_Associations (N))
2886 Pragma_Arg : Node_Id :=
2887 Expression (First (Pragma_Argument_Associations (N)));
2889 if Nkind (Pragma_Arg) = N_Selected_Component then
2890 Pragma_Arg := Selector_Name (Pragma_Arg);
2893 return Chars (Pragma_Arg) = Chars (Body_Id);
2899 end Is_Inline_Pragma;
2901 -- Start of processing for Check_Inline_Pragma
2904 if not Expander_Active then
2908 if Is_List_Member (N)
2909 and then Present (Next (N))
2910 and then Is_Inline_Pragma (Next (N))
2914 elsif Nkind (N) /= N_Subprogram_Body_Stub
2915 and then Present (Declarations (N))
2916 and then Is_Inline_Pragma (First (Declarations (N)))
2918 Prag := First (Declarations (N));
2924 if Present (Prag) then
2925 if Present (Spec_Id) then
2926 if Is_List_Member (N)
2927 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2928 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2934 -- Create a subprogram declaration, to make treatment uniform.
2935 -- Make the sloc of the subprogram name that of the entity in
2936 -- the body, so that style checks find identical strings.
2939 Subp : constant Entity_Id :=
2940 Make_Defining_Identifier
2941 (Sloc (Body_Id), Chars (Body_Id));
2942 Decl : constant Node_Id :=
2943 Make_Subprogram_Declaration (Loc,
2945 New_Copy_Tree (Specification (N)));
2948 -- Link the body and the generated spec
2950 Set_Corresponding_Body (Decl, Body_Id);
2951 Set_Corresponding_Spec (N, Subp);
2953 Set_Defining_Unit_Name (Specification (Decl), Subp);
2955 -- To ensure proper coverage when body is inlined, indicate
2956 -- whether the subprogram comes from source.
2958 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2960 if Present (First_Formal (Body_Id)) then
2961 Plist := Copy_Parameter_List (Body_Id);
2962 Set_Parameter_Specifications
2963 (Specification (Decl), Plist);
2966 -- Move aspects to the new spec
2968 if Has_Aspects (N) then
2969 Move_Aspects (N, To => Decl);
2972 Insert_Before (N, Decl);
2975 Set_Has_Pragma_Inline (Subp);
2977 if Pragma_Name (Prag) = Name_Inline_Always then
2978 Set_Is_Inlined (Subp);
2979 Set_Has_Pragma_Inline_Always (Subp);
2982 -- Prior to copying the subprogram body to create a template
2983 -- for it for subsequent inlining, remove the pragma from
2984 -- the current body so that the copy that will produce the
2985 -- new body will start from a completely unanalyzed tree.
2987 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2988 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2995 end Check_Inline_Pragma;
2997 --------------------------
2998 -- Check_Missing_Return --
2999 --------------------------
3001 procedure Check_Missing_Return is
3003 Missing_Ret : Boolean;
3006 if Nkind (Body_Spec) = N_Function_Specification then
3007 if Present (Spec_Id) then
3013 if Return_Present (Id) then
3014 Check_Returns (HSS, 'F', Missing_Ret);
3017 Set_Has_Missing_Return (Id);
3020 -- Within a premature instantiation of a package with no body, we
3021 -- build completions of the functions therein, with a Raise
3022 -- statement. No point in complaining about a missing return in
3025 elsif Ekind (Id) = E_Function
3026 and then In_Instance
3027 and then Present (Statements (HSS))
3028 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3032 elsif Is_Generic_Subprogram (Id)
3033 or else not Is_Machine_Code_Subprogram (Id)
3035 Error_Msg_N ("missing RETURN statement in function body", N);
3038 -- If procedure with No_Return, check returns
3040 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3041 if Present (Spec_Id) then
3047 if No_Return (Id) then
3048 Check_Returns (HSS, 'P', Missing_Ret, Id);
3051 end Check_Missing_Return;
3053 -----------------------
3054 -- Disambiguate_Spec --
3055 -----------------------
3057 function Disambiguate_Spec return Entity_Id is
3058 Priv_Spec : Entity_Id;
3061 procedure Replace_Types (To_Corresponding : Boolean);
3062 -- Depending on the flag, replace the type of formal parameters of
3063 -- Body_Id if it is a concurrent type implementing interfaces with
3064 -- the corresponding record type or the other way around.
3066 procedure Replace_Types (To_Corresponding : Boolean) is
3068 Formal_Typ : Entity_Id;
3071 Formal := First_Formal (Body_Id);
3072 while Present (Formal) loop
3073 Formal_Typ := Etype (Formal);
3075 if Is_Class_Wide_Type (Formal_Typ) then
3076 Formal_Typ := Root_Type (Formal_Typ);
3079 -- From concurrent type to corresponding record
3081 if To_Corresponding then
3082 if Is_Concurrent_Type (Formal_Typ)
3083 and then Present (Corresponding_Record_Type (Formal_Typ))
3086 (Corresponding_Record_Type (Formal_Typ)))
3089 Corresponding_Record_Type (Formal_Typ));
3092 -- From corresponding record to concurrent type
3095 if Is_Concurrent_Record_Type (Formal_Typ)
3096 and then Present (Interfaces (Formal_Typ))
3099 Corresponding_Concurrent_Type (Formal_Typ));
3103 Next_Formal (Formal);
3107 -- Start of processing for Disambiguate_Spec
3110 -- Try to retrieve the specification of the body as is. All error
3111 -- messages are suppressed because the body may not have a spec in
3112 -- its current state.
3114 Spec_N := Find_Corresponding_Spec (N, False);
3116 -- It is possible that this is the body of a primitive declared
3117 -- between a private and a full view of a concurrent type. The
3118 -- controlling parameter of the spec carries the concurrent type,
3119 -- not the corresponding record type as transformed by Analyze_
3120 -- Subprogram_Specification. In such cases, we undo the change
3121 -- made by the analysis of the specification and try to find the
3124 -- Note that wrappers already have their corresponding specs and
3125 -- bodies set during their creation, so if the candidate spec is
3126 -- a wrapper, then we definitely need to swap all types to their
3127 -- original concurrent status.
3130 or else Is_Primitive_Wrapper (Spec_N)
3132 -- Restore all references of corresponding record types to the
3133 -- original concurrent types.
3135 Replace_Types (To_Corresponding => False);
3136 Priv_Spec := Find_Corresponding_Spec (N, False);
3138 -- The current body truly belongs to a primitive declared between
3139 -- a private and a full view. We leave the modified body as is,
3140 -- and return the true spec.
3142 if Present (Priv_Spec)
3143 and then Is_Private_Primitive (Priv_Spec)
3148 -- In case that this is some sort of error, restore the original
3149 -- state of the body.
3151 Replace_Types (To_Corresponding => True);
3155 end Disambiguate_Spec;
3157 ----------------------------
3158 -- Exchange_Limited_Views --
3159 ----------------------------
3161 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3162 Result : Elist_Id := No_Elist;
3164 procedure Detect_And_Exchange (Id : Entity_Id);
3165 -- Determine whether Id's type denotes an incomplete type associated
3166 -- with a limited with clause and exchange the limited view with the
3167 -- non-limited one when available. Note that the non-limited view
3168 -- may exist because of a with_clause in another unit in the context,
3169 -- but cannot be used because the current view of the enclosing unit
3170 -- is still a limited view.
3172 -------------------------
3173 -- Detect_And_Exchange --
3174 -------------------------
3176 procedure Detect_And_Exchange (Id : Entity_Id) is
3177 Typ : constant Entity_Id := Etype (Id);
3179 if From_Limited_With (Typ)
3180 and then Has_Non_Limited_View (Typ)
3181 and then not From_Limited_With (Scope (Typ))
3184 Result := New_Elmt_List;
3187 Prepend_Elmt (Typ, Result);
3188 Prepend_Elmt (Id, Result);
3189 Set_Etype (Id, Non_Limited_View (Typ));
3191 end Detect_And_Exchange;
3197 -- Start of processing for Exchange_Limited_Views
3200 -- Do not process subprogram bodies as they already use the non-
3201 -- limited view of types.
3203 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3207 -- Examine all formals and swap views when applicable
3209 Formal := First_Formal (Subp_Id);
3210 while Present (Formal) loop
3211 Detect_And_Exchange (Formal);
3213 Next_Formal (Formal);
3216 -- Process the return type of a function
3218 if Ekind (Subp_Id) = E_Function then
3219 Detect_And_Exchange (Subp_Id);
3223 end Exchange_Limited_Views;
3225 -------------------------------------
3226 -- Is_Private_Concurrent_Primitive --
3227 -------------------------------------
3229 function Is_Private_Concurrent_Primitive
3230 (Subp_Id : Entity_Id) return Boolean
3232 Formal_Typ : Entity_Id;
3235 if Present (First_Formal (Subp_Id)) then
3236 Formal_Typ := Etype (First_Formal (Subp_Id));
3238 if Is_Concurrent_Record_Type (Formal_Typ) then
3239 if Is_Class_Wide_Type (Formal_Typ) then
3240 Formal_Typ := Root_Type (Formal_Typ);
3243 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3246 -- The type of the first formal is a concurrent tagged type with
3250 Is_Concurrent_Type (Formal_Typ)
3251 and then Is_Tagged_Type (Formal_Typ)
3252 and then Has_Private_Declaration (Formal_Typ);
3256 end Is_Private_Concurrent_Primitive;
3258 -------------------------
3259 -- Mask_Unfrozen_Types --
3260 -------------------------
3262 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3263 Result : Elist_Id := No_Elist;
3265 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3266 -- Mask all types referenced in the subtree rooted at Node
3268 --------------------
3269 -- Mask_Type_Refs --
3270 --------------------
3272 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3273 procedure Mask_Type (Typ : Entity_Id);
3274 -- ??? what does this do?
3280 procedure Mask_Type (Typ : Entity_Id) is
3282 -- Skip Itypes created by the preanalysis
3285 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3290 if not Is_Frozen (Typ) then
3291 if Scope (Typ) /= Current_Scope then
3292 Set_Is_Frozen (Typ);
3293 Append_New_Elmt (Typ, Result);
3295 Freeze_Before (N, Typ);
3300 -- Start of processing for Mask_Type_Refs
3303 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3304 Mask_Type (Etype (Entity (Node)));
3306 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3307 Mask_Type (Scope (Entity (Node)));
3310 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3311 and then Present (Etype (Node))
3313 Mask_Type (Etype (Node));
3319 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3323 Return_Stmt : constant Node_Id :=
3324 First (Statements (Handled_Statement_Sequence (N)));
3326 -- Start of processing for Mask_Unfrozen_Types
3329 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3331 Mask_References (Expression (Return_Stmt));
3334 end Mask_Unfrozen_Types;
3336 ---------------------------
3337 -- Restore_Limited_Views --
3338 ---------------------------
3340 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3341 Elmt : Elmt_Id := First_Elmt (Restore_List);
3345 while Present (Elmt) loop
3348 Set_Etype (Id, Node (Elmt));
3351 end Restore_Limited_Views;
3353 ----------------------------
3354 -- Set_Trivial_Subprogram --
3355 ----------------------------
3357 procedure Set_Trivial_Subprogram (N : Node_Id) is
3358 Nxt : constant Node_Id := Next (N);
3361 Set_Is_Trivial_Subprogram (Body_Id);
3363 if Present (Spec_Id) then
3364 Set_Is_Trivial_Subprogram (Spec_Id);
3368 and then Nkind (Nxt) = N_Simple_Return_Statement
3369 and then No (Next (Nxt))
3370 and then Present (Expression (Nxt))
3371 and then Is_Entity_Name (Expression (Nxt))
3373 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3375 end Set_Trivial_Subprogram;
3377 ---------------------------
3378 -- Unmask_Unfrozen_Types --
3379 ---------------------------
3381 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3382 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3385 while Present (Elmt) loop
3386 Set_Is_Frozen (Node (Elmt), False);
3389 end Unmask_Unfrozen_Types;
3391 ---------------------------------
3392 -- Verify_Overriding_Indicator --
3393 ---------------------------------
3395 procedure Verify_Overriding_Indicator is
3397 if Must_Override (Body_Spec) then
3398 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3399 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3403 -- Overridden controlled primitives may have had their
3404 -- Overridden_Operation field cleared according to the setting of
3405 -- the Is_Hidden flag. An issue arises, however, when analyzing
3406 -- an instance that may have manipulated the flag during
3407 -- expansion. As a result, we add an exception for this case.
3409 elsif not Present (Overridden_Operation (Spec_Id))
3410 and then not (Nam_In (Chars (Spec_Id), Name_Adjust,
3413 and then In_Instance)
3416 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3418 -- Overriding indicators aren't allowed for protected subprogram
3419 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3420 -- this to a warning if -gnatd.E is enabled.
3422 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3423 Error_Msg_Warn := Error_To_Warning;
3425 ("<<overriding indicator not allowed for protected "
3426 & "subprogram body", Body_Spec);
3429 elsif Must_Not_Override (Body_Spec) then
3430 if Present (Overridden_Operation (Spec_Id)) then
3432 ("subprogram& overrides inherited operation",
3433 Body_Spec, Spec_Id);
3435 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3436 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3439 ("subprogram& overrides predefined operator ",
3440 Body_Spec, Spec_Id);
3442 -- Overriding indicators aren't allowed for protected subprogram
3443 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3444 -- this to a warning if -gnatd.E is enabled.
3446 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3447 Error_Msg_Warn := Error_To_Warning;
3450 ("<<overriding indicator not allowed "
3451 & "for protected subprogram body", Body_Spec);
3453 -- If this is not a primitive operation, then the overriding
3454 -- indicator is altogether illegal.
3456 elsif not Is_Primitive (Spec_Id) then
3458 ("overriding indicator only allowed "
3459 & "if subprogram is primitive", Body_Spec);
3462 -- If checking the style rule and the operation overrides, then
3463 -- issue a warning about a missing overriding_indicator. Protected
3464 -- subprogram bodies are excluded from this style checking, since
3465 -- they aren't primitives (even though their declarations can
3466 -- override) and aren't allowed to have an overriding_indicator.
3469 and then Present (Overridden_Operation (Spec_Id))
3470 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3472 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3473 Style.Missing_Overriding (N, Body_Id);
3476 and then Can_Override_Operator (Spec_Id)
3477 and then not In_Predefined_Unit (Spec_Id)
3479 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3480 Style.Missing_Overriding (N, Body_Id);
3482 end Verify_Overriding_Indicator;
3486 Body_Nod : Node_Id := Empty;
3487 Minimum_Acc_Objs : List_Id := No_List;
3489 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3490 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3491 Saved_EA : constant Boolean := Expander_Active;
3492 Saved_ISMP : constant Boolean :=
3493 Ignore_SPARK_Mode_Pragmas_In_Instance;
3494 -- Save the Ghost and SPARK mode-related data to restore on exit
3496 -- Start of processing for Analyze_Subprogram_Body_Helper
3499 -- A [generic] subprogram body freezes the contract of the nearest
3500 -- enclosing package body and all other contracts encountered in the
3501 -- same declarative part up to and excluding the subprogram body:
3503 -- package body Nearest_Enclosing_Package
3504 -- with Refined_State => (State => Constit)
3508 -- procedure Freezes_Enclosing_Package_Body
3509 -- with Refined_Depends => (Input => Constit) ...
3511 -- This ensures that any annotations referenced by the contract of the
3512 -- [generic] subprogram body are available. This form of freezing is
3513 -- decoupled from the usual Freeze_xxx mechanism because it must also
3514 -- work in the context of generics where normal freezing is disabled.
3516 -- Only bodies coming from source should cause this type of freezing.
3517 -- Expression functions that act as bodies and complete an initial
3518 -- declaration must be included in this category, hence the use of
3521 if Comes_From_Source (Original_Node (N)) then
3522 Freeze_Previous_Contracts (N);
3525 -- Generic subprograms are handled separately. They always have a
3526 -- generic specification. Determine whether current scope has a
3527 -- previous declaration.
3529 -- If the subprogram body is defined within an instance of the same
3530 -- name, the instance appears as a package renaming, and will be hidden
3531 -- within the subprogram.
3533 if Present (Prev_Id)
3534 and then not Is_Overloadable (Prev_Id)
3535 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3536 or else Comes_From_Source (Prev_Id))
3538 if Is_Generic_Subprogram (Prev_Id) then
3541 -- A subprogram body is Ghost when it is stand-alone and subject
3542 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3543 -- the mode now to ensure that any nodes generated during analysis
3544 -- and expansion are properly marked as Ghost.
3546 Mark_And_Set_Ghost_Body (N, Spec_Id);
3548 -- If the body completes the initial declaration of a compilation
3549 -- unit which is subject to pragma Elaboration_Checks, set the
3550 -- model specified by the pragma because it applies to all parts
3553 Install_Elaboration_Model (Spec_Id);
3555 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3556 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3558 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3560 if Nkind (N) = N_Subprogram_Body then
3561 HSS := Handled_Statement_Sequence (N);
3562 Check_Missing_Return;
3567 -- Otherwise a previous entity conflicts with the subprogram name.
3568 -- Attempting to enter name will post error.
3571 Enter_Name (Body_Id);
3575 -- Non-generic case, find the subprogram declaration, if one was seen,
3576 -- or enter new overloaded entity in the current scope. If the
3577 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3578 -- part of the context of one of its subunits. No need to redo the
3581 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3585 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3587 if Nkind (N) = N_Subprogram_Body_Stub
3588 or else No (Corresponding_Spec (N))
3590 if Is_Private_Concurrent_Primitive (Body_Id) then
3591 Spec_Id := Disambiguate_Spec;
3593 -- A subprogram body is Ghost when it is stand-alone and
3594 -- subject to pragma Ghost or when the corresponding spec is
3595 -- Ghost. Set the mode now to ensure that any nodes generated
3596 -- during analysis and expansion are properly marked as Ghost.
3598 Mark_And_Set_Ghost_Body (N, Spec_Id);
3600 -- If the body completes a compilation unit which is subject
3601 -- to pragma Elaboration_Checks, set the model specified by
3602 -- the pragma because it applies to all parts of the unit.
3604 Install_Elaboration_Model (Spec_Id);
3607 Spec_Id := Find_Corresponding_Spec (N);
3609 -- A subprogram body is Ghost when it is stand-alone and
3610 -- subject to pragma Ghost or when the corresponding spec is
3611 -- Ghost. Set the mode now to ensure that any nodes generated
3612 -- during analysis and expansion are properly marked as Ghost.
3614 Mark_And_Set_Ghost_Body (N, Spec_Id);
3616 -- If the body completes a compilation unit which is subject
3617 -- to pragma Elaboration_Checks, set the model specified by
3618 -- the pragma because it applies to all parts of the unit.
3620 Install_Elaboration_Model (Spec_Id);
3622 -- In GNATprove mode, if the body has no previous spec, create
3623 -- one so that the inlining machinery can operate properly.
3624 -- Transfer aspects, if any, to the new spec, so that they
3625 -- are legal and can be processed ahead of the body.
3626 -- We make two copies of the given spec, one for the new
3627 -- declaration, and one for the body.
3629 if No (Spec_Id) and then GNATprove_Mode
3631 -- Inlining does not apply during preanalysis of code
3633 and then Full_Analysis
3635 -- Inlining only applies to full bodies, not stubs
3637 and then Nkind (N) /= N_Subprogram_Body_Stub
3639 -- Inlining only applies to bodies in the source code, not to
3640 -- those generated by the compiler. In particular, expression
3641 -- functions, whose body is generated by the compiler, are
3642 -- treated specially by GNATprove.
3644 and then Comes_From_Source (Body_Id)
3646 -- This cannot be done for a compilation unit, which is not
3647 -- in a context where we can insert a new spec.
3649 and then Is_List_Member (N)
3651 -- Inlining only applies to subprograms without contracts,
3652 -- as a contract is a sign that GNATprove should perform a
3653 -- modular analysis of the subprogram instead of a contextual
3654 -- analysis at each call site. The same test is performed in
3655 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3656 -- here in another form (because the contract has not been
3657 -- attached to the body) to avoid front-end errors in case
3658 -- pragmas are used instead of aspects, because the
3659 -- corresponding pragmas in the body would not be transferred
3660 -- to the spec, leading to legality errors.
3662 and then not Body_Has_Contract
3663 and then not Inside_A_Generic
3665 Build_Subprogram_Declaration;
3667 -- If this is a function that returns a constrained array, and
3668 -- we are generating SPARK_For_C, create subprogram declaration
3669 -- to simplify subsequent C generation.
3672 and then Modify_Tree_For_C
3673 and then Nkind (Body_Spec) = N_Function_Specification
3674 and then Is_Array_Type (Etype (Body_Id))
3675 and then Is_Constrained (Etype (Body_Id))
3677 Build_Subprogram_Declaration;
3681 -- If this is a duplicate body, no point in analyzing it
3683 if Error_Posted (N) then
3687 -- A subprogram body should cause freezing of its own declaration,
3688 -- but if there was no previous explicit declaration, then the
3689 -- subprogram will get frozen too late (there may be code within
3690 -- the body that depends on the subprogram having been frozen,
3691 -- such as uses of extra formals), so we force it to be frozen
3692 -- here. Same holds if the body and spec are compilation units.
3693 -- Finally, if the return type is an anonymous access to protected
3694 -- subprogram, it must be frozen before the body because its
3695 -- expansion has generated an equivalent type that is used when
3696 -- elaborating the body.
3698 -- An exception in the case of Ada 2012, AI05-177: The bodies
3699 -- created for expression functions do not freeze.
3702 and then Nkind (Original_Node (N)) /= N_Expression_Function
3704 Freeze_Before (N, Body_Id);
3706 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3707 Freeze_Before (N, Spec_Id);
3709 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3710 Freeze_Before (N, Etype (Body_Id));
3714 Spec_Id := Corresponding_Spec (N);
3716 -- A subprogram body is Ghost when it is stand-alone and subject
3717 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3718 -- the mode now to ensure that any nodes generated during analysis
3719 -- and expansion are properly marked as Ghost.
3721 Mark_And_Set_Ghost_Body (N, Spec_Id);
3723 -- If the body completes the initial declaration of a compilation
3724 -- unit which is subject to pragma Elaboration_Checks, set the
3725 -- model specified by the pragma because it applies to all parts
3728 Install_Elaboration_Model (Spec_Id);
3732 -- Deactivate expansion inside the body of ignored Ghost entities,
3733 -- as this code will ultimately be ignored. This avoids requiring the
3734 -- presence of run-time units which are not needed. Only do this for
3735 -- user entities, as internally generated entitities might still need
3736 -- to be expanded (e.g. those generated for types).
3738 if Present (Ignored_Ghost_Region)
3739 and then Comes_From_Source (Body_Id)
3741 Expander_Active := False;
3744 -- Previously we scanned the body to look for nested subprograms, and
3745 -- rejected an inline directive if nested subprograms were present,
3746 -- because the back-end would generate conflicting symbols for the
3747 -- nested bodies. This is now unnecessary.
3749 -- Look ahead to recognize a pragma Inline that appears after the body
3751 Check_Inline_Pragma (Spec_Id);
3753 -- Deal with special case of a fully private operation in the body of
3754 -- the protected type. We must create a declaration for the subprogram,
3755 -- in order to attach the protected subprogram that will be used in
3756 -- internal calls. We exclude compiler generated bodies from the
3757 -- expander since the issue does not arise for those cases.
3760 and then Comes_From_Source (N)
3761 and then Is_Protected_Type (Current_Scope)
3763 Spec_Id := Build_Private_Protected_Declaration (N);
3766 -- If we are generating C and this is a function returning a constrained
3767 -- array type for which we must create a procedure with an extra out
3768 -- parameter, build and analyze the body now. The procedure declaration
3769 -- has already been created. We reuse the source body of the function,
3770 -- because in an instance it may contain global references that cannot
3771 -- be reanalyzed. The source function itself is not used any further,
3772 -- so we mark it as having a completion. If the subprogram is a stub the
3773 -- transformation is done later, when the proper body is analyzed.
3776 and then Modify_Tree_For_C
3777 and then Present (Spec_Id)
3778 and then Ekind (Spec_Id) = E_Function
3779 and then Nkind (N) /= N_Subprogram_Body_Stub
3780 and then Rewritten_For_C (Spec_Id)
3782 Set_Has_Completion (Spec_Id);
3784 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3787 -- The entity for the created procedure must remain invisible, so it
3788 -- does not participate in resolution of subsequent references to the
3791 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3795 -- If a separate spec is present, then deal with freezing issues
3797 if Present (Spec_Id) then
3798 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3799 Verify_Overriding_Indicator;
3801 -- In general, the spec will be frozen when we start analyzing the
3802 -- body. However, for internally generated operations, such as
3803 -- wrapper functions for inherited operations with controlling
3804 -- results, the spec may not have been frozen by the time we expand
3805 -- the freeze actions that include the bodies. In particular, extra
3806 -- formals for accessibility or for return-in-place may need to be
3807 -- generated. Freeze nodes, if any, are inserted before the current
3808 -- body. These freeze actions are also needed in Compile_Only mode to
3809 -- enable the proper back-end type annotations.
3810 -- They are necessary in any case to ensure proper elaboration order
3813 if Nkind (N) = N_Subprogram_Body
3814 and then Was_Expression_Function (N)
3815 and then not Has_Completion (Spec_Id)
3816 and then Serious_Errors_Detected = 0
3817 and then (Expander_Active
3818 or else Operating_Mode = Check_Semantics
3819 or else Is_Ignored_Ghost_Entity (Spec_Id))
3821 -- The body generated for an expression function that is not a
3822 -- completion is a freeze point neither for the profile nor for
3823 -- anything else. That's why, in order to prevent any freezing
3824 -- during analysis, we need to mask types declared outside the
3825 -- expression (and in an outer scope) that are not yet frozen.
3826 -- This also needs to be done in the case of an ignored Ghost
3827 -- expression function, where the expander isn't active.
3829 Set_Is_Frozen (Spec_Id);
3830 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3832 elsif not Is_Frozen (Spec_Id)
3833 and then Serious_Errors_Detected = 0
3835 Set_Has_Delayed_Freeze (Spec_Id);
3836 Freeze_Before (N, Spec_Id);
3840 -- If the subprogram has a class-wide clone, build its body as a copy
3841 -- of the original body, and rewrite body of original subprogram as a
3842 -- wrapper that calls the clone. If N is a stub, this construction will
3843 -- take place when the proper body is analyzed. No action needed if this
3844 -- subprogram has been eliminated.
3846 if Present (Spec_Id)
3847 and then Present (Class_Wide_Clone (Spec_Id))
3848 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3849 and then Nkind (N) /= N_Subprogram_Body_Stub
3850 and then not (Expander_Active and then Is_Eliminated (Spec_Id))
3852 Build_Class_Wide_Clone_Body (Spec_Id, N);
3854 -- This is the new body for the existing primitive operation
3856 Rewrite (N, Build_Class_Wide_Clone_Call
3857 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3858 Set_Has_Completion (Spec_Id, False);
3863 -- Place subprogram on scope stack, and make formals visible. If there
3864 -- is a spec, the visible entity remains that of the spec.
3866 if Present (Spec_Id) then
3867 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3869 if Is_Child_Unit (Spec_Id) then
3870 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3874 Style.Check_Identifier (Body_Id, Spec_Id);
3877 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3878 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3880 if Is_Abstract_Subprogram (Spec_Id) then
3881 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3885 Set_Convention (Body_Id, Convention (Spec_Id));
3886 Set_Has_Completion (Spec_Id);
3888 if Is_Protected_Type (Scope (Spec_Id)) then
3889 Prot_Typ := Scope (Spec_Id);
3892 -- If this is a body generated for a renaming, do not check for
3893 -- full conformance. The check is redundant, because the spec of
3894 -- the body is a copy of the spec in the renaming declaration,
3895 -- and the test can lead to spurious errors on nested defaults.
3897 if Present (Spec_Decl)
3898 and then not Comes_From_Source (N)
3900 (Nkind (Original_Node (Spec_Decl)) =
3901 N_Subprogram_Renaming_Declaration
3902 or else (Present (Corresponding_Body (Spec_Decl))
3904 Nkind (Unit_Declaration_Node
3905 (Corresponding_Body (Spec_Decl))) =
3906 N_Subprogram_Renaming_Declaration))
3910 -- Conversely, the spec may have been generated for specless body
3911 -- with an inline pragma. The entity comes from source, which is
3912 -- both semantically correct and necessary for proper inlining.
3913 -- The subprogram declaration itself is not in the source.
3915 elsif Comes_From_Source (N)
3916 and then Present (Spec_Decl)
3917 and then not Comes_From_Source (Spec_Decl)
3918 and then Has_Pragma_Inline (Spec_Id)
3925 Fully_Conformant, True, Conformant, Body_Id);
3928 -- If the body is not fully conformant, we have to decide if we
3929 -- should analyze it or not. If it has a really messed up profile
3930 -- then we probably should not analyze it, since we will get too
3931 -- many bogus messages.
3933 -- Our decision is to go ahead in the non-fully conformant case
3934 -- only if it is at least mode conformant with the spec. Note
3935 -- that the call to Check_Fully_Conformant has issued the proper
3936 -- error messages to complain about the lack of conformance.
3939 and then not Mode_Conformant (Body_Id, Spec_Id)
3945 -- In the case we are dealing with an expression function we check
3946 -- the formals attached to the spec instead of the body - so we don't
3947 -- reference body formals.
3949 if Spec_Id /= Body_Id
3950 and then not Is_Expression_Function (Spec_Id)
3952 Reference_Body_Formals (Spec_Id, Body_Id);
3955 Set_Ekind (Body_Id, E_Subprogram_Body);
3957 if Nkind (N) = N_Subprogram_Body_Stub then
3958 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3963 Set_Corresponding_Spec (N, Spec_Id);
3965 -- Ada 2005 (AI-345): If the operation is a primitive operation
3966 -- of a concurrent type, the type of the first parameter has been
3967 -- replaced with the corresponding record, which is the proper
3968 -- run-time structure to use. However, within the body there may
3969 -- be uses of the formals that depend on primitive operations
3970 -- of the type (in particular calls in prefixed form) for which
3971 -- we need the original concurrent type. The operation may have
3972 -- several controlling formals, so the replacement must be done
3975 if Comes_From_Source (Spec_Id)
3976 and then Present (First_Entity (Spec_Id))
3977 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3978 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3979 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3980 and then Present (Corresponding_Concurrent_Type
3981 (Etype (First_Entity (Spec_Id))))
3984 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3988 Form := First_Formal (Spec_Id);
3989 while Present (Form) loop
3990 if Etype (Form) = Typ then
3991 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3999 -- Make the formals visible, and place subprogram on scope stack.
4000 -- This is also the point at which we set Last_Real_Spec_Entity
4001 -- to mark the entities which will not be moved to the body.
4003 Install_Formals (Spec_Id);
4004 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
4006 -- Within an instance, add local renaming declarations so that
4007 -- gdb can retrieve the values of actuals more easily. This is
4008 -- only relevant if generating code.
4010 if Is_Generic_Instance (Spec_Id)
4011 and then Is_Wrapper_Package (Current_Scope)
4012 and then Expander_Active
4014 Build_Subprogram_Instance_Renamings (N, Current_Scope);
4017 Push_Scope (Spec_Id);
4019 -- Make sure that the subprogram is immediately visible. For
4020 -- child units that have no separate spec this is indispensable.
4021 -- Otherwise it is safe albeit redundant.
4023 Set_Is_Immediately_Visible (Spec_Id);
4026 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
4027 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
4028 Set_Scope (Body_Id, Scope (Spec_Id));
4030 -- Case of subprogram body with no previous spec
4033 -- Check for style warning required
4037 -- Only apply check for source level subprograms for which checks
4038 -- have not been suppressed.
4040 and then Comes_From_Source (Body_Id)
4041 and then not Suppress_Style_Checks (Body_Id)
4043 -- No warnings within an instance
4045 and then not In_Instance
4047 -- No warnings for expression functions
4049 and then Nkind (Original_Node (N)) /= N_Expression_Function
4051 Style.Body_With_No_Spec (N);
4054 New_Overloaded_Entity (Body_Id);
4056 if Nkind (N) /= N_Subprogram_Body_Stub then
4057 Set_Acts_As_Spec (N);
4058 Generate_Definition (Body_Id);
4060 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
4062 -- If the body is an entry wrapper created for an entry with
4063 -- preconditions, it must be compiled in the context of the
4064 -- enclosing synchronized object, because it may mention other
4065 -- operations of the type.
4067 if Is_Entry_Wrapper (Body_Id) then
4069 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4072 Install_Declarations (Prot);
4076 Install_Formals (Body_Id);
4078 Push_Scope (Body_Id);
4081 -- For stubs and bodies with no previous spec, generate references to
4084 Generate_Reference_To_Formals (Body_Id);
4087 -- Entry barrier functions are generated outside the protected type and
4088 -- should not carry the SPARK_Mode of the enclosing context.
4090 if Nkind (N) = N_Subprogram_Body
4091 and then Is_Entry_Barrier_Function (N)
4095 -- The body is generated as part of expression function expansion. When
4096 -- the expression function appears in the visible declarations of a
4097 -- package, the body is added to the private declarations. Since both
4098 -- declarative lists may be subject to a different SPARK_Mode, inherit
4099 -- the mode of the spec.
4101 -- package P with SPARK_Mode is
4102 -- function Expr_Func ... is (...); -- original
4103 -- [function Expr_Func ...;] -- generated spec
4106 -- pragma SPARK_Mode (Off);
4107 -- [function Expr_Func ... is return ...;] -- generated body
4108 -- end P; -- mode is ON
4110 elsif not Comes_From_Source (N)
4111 and then Present (Spec_Id)
4112 and then Is_Expression_Function (Spec_Id)
4114 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4115 Set_SPARK_Pragma_Inherited
4116 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4118 -- Set the SPARK_Mode from the current context (may be overwritten later
4119 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4120 -- initially on a stand-alone subprogram body, but is then relocated to
4121 -- a generated corresponding spec. In this scenario the mode is shared
4122 -- between the spec and body.
4124 elsif No (SPARK_Pragma (Body_Id)) then
4125 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4126 Set_SPARK_Pragma_Inherited (Body_Id);
4129 -- A subprogram body may be instantiated or inlined at a later pass.
4130 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4131 -- applied to the initial declaration of the body.
4133 if Present (Spec_Id) then
4134 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4135 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4139 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4140 -- case the body is instantiated or inlined later and out of context.
4141 -- The body uses this attribute to restore the value of the global
4144 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4145 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4147 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4148 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4152 -- Preserve relevant elaboration-related attributes of the context which
4153 -- are no longer available or very expensive to recompute once analysis,
4154 -- resolution, and expansion are over.
4156 if No (Spec_Id) then
4157 Mark_Elaboration_Attributes
4163 -- If this is the proper body of a stub, we must verify that the stub
4164 -- conforms to the body, and to the previous spec if one was present.
4165 -- We know already that the body conforms to that spec. This test is
4166 -- only required for subprograms that come from source.
4168 if Nkind (Parent (N)) = N_Subunit
4169 and then Comes_From_Source (N)
4170 and then not Error_Posted (Body_Id)
4171 and then Nkind (Corresponding_Stub (Parent (N))) =
4172 N_Subprogram_Body_Stub
4175 Old_Id : constant Entity_Id :=
4177 (Specification (Corresponding_Stub (Parent (N))));
4179 Conformant : Boolean := False;
4182 if No (Spec_Id) then
4183 Check_Fully_Conformant (Body_Id, Old_Id);
4187 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4189 if not Conformant then
4191 -- The stub was taken to be a new declaration. Indicate that
4194 Set_Has_Completion (Old_Id, False);
4200 Set_Has_Completion (Body_Id);
4201 Check_Eliminated (Body_Id);
4203 -- Analyze any aspect specifications that appear on the subprogram body
4204 -- stub. Stop the analysis now as the stub does not have a declarative
4205 -- or a statement part, and it cannot be inlined.
4207 if Nkind (N) = N_Subprogram_Body_Stub then
4208 if Has_Aspects (N) then
4209 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4217 -- Note: Normally we don't do any inlining if expansion is off, since
4218 -- we won't generate code in any case. An exception arises in GNATprove
4219 -- mode where we want to expand some calls in place, even with expansion
4220 -- disabled, since the inlining eases formal verification.
4222 if not GNATprove_Mode
4223 and then Expander_Active
4224 and then Serious_Errors_Detected = 0
4225 and then Present (Spec_Id)
4226 and then Has_Pragma_Inline (Spec_Id)
4228 -- Legacy implementation (relying on front-end inlining)
4230 if not Back_End_Inlining then
4231 if Has_Pragma_Inline_Always (Spec_Id)
4232 or else (Front_End_Inlining
4233 and then not Opt.Disable_FE_Inline)
4235 Build_Body_To_Inline (N, Spec_Id);
4238 -- New implementation (relying on back-end inlining)
4241 if Has_Pragma_Inline_Always (Spec_Id)
4242 or else Optimization_Level > 0
4244 -- Handle function returning an unconstrained type
4246 if Comes_From_Source (Body_Id)
4247 and then Ekind (Spec_Id) = E_Function
4248 and then Returns_Unconstrained_Type (Spec_Id)
4250 -- If function builds in place, i.e. returns a limited type,
4251 -- inlining cannot be done.
4253 and then not Is_Limited_Type (Etype (Spec_Id))
4255 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4259 Subp_Body : constant Node_Id :=
4260 Unit_Declaration_Node (Body_Id);
4261 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4264 -- Do not pass inlining to the backend if the subprogram
4265 -- has declarations or statements which cannot be inlined
4266 -- by the backend. This check is done here to emit an
4267 -- error instead of the generic warning message reported
4268 -- by the GCC backend (ie. "function might not be
4271 if Present (Subp_Decl)
4272 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4276 elsif Has_Excluded_Statement
4279 (Handled_Statement_Sequence (Subp_Body)))
4283 -- If the backend inlining is available then at this
4284 -- stage we only have to mark the subprogram as inlined.
4285 -- The expander will take care of registering it in the
4286 -- table of subprograms inlined by the backend a part of
4287 -- processing calls to it (cf. Expand_Call)
4290 Set_Is_Inlined (Spec_Id);
4297 -- In GNATprove mode, inline only when there is a separate subprogram
4298 -- declaration for now, as inlining of subprogram bodies acting as
4299 -- declarations, or subprogram stubs, are not supported by front-end
4300 -- inlining. This inlining should occur after analysis of the body, so
4301 -- that it is known whether the value of SPARK_Mode, which can be
4302 -- defined by a pragma inside the body, is applicable to the body.
4303 -- Inlining can be disabled with switch -gnatdm
4305 elsif GNATprove_Mode
4306 and then Full_Analysis
4307 and then not Inside_A_Generic
4308 and then Present (Spec_Id)
4310 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4311 and then Body_Has_SPARK_Mode_On
4312 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4313 and then not Body_Has_Contract
4314 and then not Debug_Flag_M
4316 Build_Body_To_Inline (N, Spec_Id);
4319 -- When generating code, inherited pre/postconditions are handled when
4320 -- expanding the corresponding contract.
4322 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4323 -- of the specification we have to install the private withed units.
4324 -- This holds for child units as well.
4326 if Is_Compilation_Unit (Body_Id)
4327 or else Nkind (Parent (N)) = N_Compilation_Unit
4329 Install_Private_With_Clauses (Body_Id);
4332 Check_Anonymous_Return;
4334 -- Set the Protected_Formal field of each extra formal of the protected
4335 -- subprogram to reference the corresponding extra formal of the
4336 -- subprogram that implements it. For regular formals this occurs when
4337 -- the protected subprogram's declaration is expanded, but the extra
4338 -- formals don't get created until the subprogram is frozen. We need to
4339 -- do this before analyzing the protected subprogram's body so that any
4340 -- references to the original subprogram's extra formals will be changed
4341 -- refer to the implementing subprogram's formals (see Expand_Formal).
4343 if Present (Spec_Id)
4344 and then Is_Protected_Type (Scope (Spec_Id))
4345 and then Present (Protected_Body_Subprogram (Spec_Id))
4348 Impl_Subp : constant Entity_Id :=
4349 Protected_Body_Subprogram (Spec_Id);
4350 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4351 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4354 while Present (Prot_Ext_Formal) loop
4355 pragma Assert (Present (Impl_Ext_Formal));
4356 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4357 Next_Formal_With_Extras (Prot_Ext_Formal);
4358 Next_Formal_With_Extras (Impl_Ext_Formal);
4363 -- Generate minimum accessibility local objects to correspond with
4364 -- any extra formal added for anonymous access types. This new local
4365 -- object can then be used instead of the formal in case it is used
4366 -- in an actual to a call to a nested subprogram.
4368 -- This method is used to supplement our "small integer model" for
4369 -- accessibility-check generation (for more information see
4370 -- Dynamic_Accessibility_Level).
4372 -- Because we allow accessibility values greater than our expected value
4373 -- passing along the same extra accessibility formal as an actual
4374 -- to a nested subprogram becomes a problem because high values mean
4375 -- different things to the callee even though they are the same to the
4376 -- caller. So, as described in the first section, we create a local
4377 -- object representing the minimum of the accessibility level value that
4378 -- is passed in and the accessibility level of the callee's parameter
4379 -- and locals and use it in the case of a call to a nested subprogram.
4380 -- This generated object is refered to as a "minimum accessiblity
4383 if Present (Spec_Id) or else Present (Body_Id) then
4384 Body_Nod := Unit_Declaration_Node (Body_Id);
4389 -- Grab the appropriate formal depending on whether there exists
4390 -- an actual spec for the subprogram or whether we are dealing
4391 -- with a protected subprogram.
4393 if Present (Spec_Id) then
4394 if Present (Protected_Body_Subprogram (Spec_Id)) then
4395 Form := First_Formal (Protected_Body_Subprogram (Spec_Id));
4397 Form := First_Formal (Spec_Id);
4400 Form := First_Formal (Body_Id);
4403 -- Loop through formals if the subprogram is capable of accepting
4404 -- a generated local object. If it is not then it is also not
4405 -- capable of having local subprograms meaning it would not need
4406 -- a minimum accessibility level object anyway.
4408 if Present (Body_Nod)
4409 and then Has_Declarations (Body_Nod)
4410 and then Nkind (Body_Nod) /= N_Package_Specification
4412 while Present (Form) loop
4414 if Present (Extra_Accessibility (Form))
4415 and then No (Minimum_Accessibility (Form))
4417 -- Generate the minimum accessibility level object
4419 -- A60b : integer := integer'min(2, paramL);
4422 Loc : constant Source_Ptr := Sloc (Body_Nod);
4423 Obj_Node : constant Node_Id :=
4424 Make_Object_Declaration (Loc,
4425 Defining_Identifier =>
4427 (Loc, 'A', Extra_Accessibility (Form)),
4428 Object_Definition => New_Occurrence_Of
4429 (Standard_Integer, Loc),
4431 Make_Attribute_Reference (Loc,
4432 Prefix => New_Occurrence_Of
4433 (Standard_Integer, Loc),
4434 Attribute_Name => Name_Min,
4435 Expressions => New_List (
4436 Make_Integer_Literal (Loc,
4437 Object_Access_Level (Form)),
4439 (Extra_Accessibility (Form), Loc))));
4441 -- Add the new local object to the Minimum_Acc_Obj to
4442 -- be later prepended to the subprogram's list of
4443 -- declarations after we are sure all expansion is
4446 if Present (Minimum_Acc_Objs) then
4447 Prepend (Obj_Node, Minimum_Acc_Objs);
4449 Minimum_Acc_Objs := New_List (Obj_Node);
4452 -- Register the object and analyze it
4454 Set_Minimum_Accessibility
4455 (Form, Defining_Identifier (Obj_Node));
4467 -- Now we can go on to analyze the body
4469 HSS := Handled_Statement_Sequence (N);
4470 Set_Actual_Subtypes (N, Current_Scope);
4472 -- Add a declaration for the Protection object, renaming declarations
4473 -- for discriminals and privals and finally a declaration for the entry
4474 -- family index (if applicable). This form of early expansion is done
4475 -- when the Expander is active because Install_Private_Data_Declarations
4476 -- references entities which were created during regular expansion. The
4477 -- subprogram entity must come from source, and not be an internally
4478 -- generated subprogram.
4481 and then Present (Prot_Typ)
4482 and then Present (Spec_Id)
4483 and then Comes_From_Source (Spec_Id)
4484 and then not Is_Eliminated (Spec_Id)
4486 Install_Private_Data_Declarations
4487 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4490 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4491 -- may now appear in parameter and result profiles. Since the analysis
4492 -- of a subprogram body may use the parameter and result profile of the
4493 -- spec, swap any limited views with their non-limited counterpart.
4495 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4496 Exch_Views := Exchange_Limited_Views (Spec_Id);
4499 -- If the return type is an anonymous access type whose designated type
4500 -- is the limited view of a class-wide type and the non-limited view is
4501 -- available, update the return type accordingly.
4503 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4509 Rtyp := Etype (Spec_Id);
4511 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4512 Etyp := Directly_Designated_Type (Rtyp);
4514 if Is_Class_Wide_Type (Etyp)
4515 and then From_Limited_With (Etyp)
4518 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4524 -- Analyze any aspect specifications that appear on the subprogram body
4526 if Has_Aspects (N) then
4527 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4530 Analyze_Declarations (Declarations (N));
4532 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4534 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4535 if Present (SPARK_Pragma (Spec_Id)) then
4536 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4538 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4540 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4541 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4542 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4544 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4547 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4550 -- SPARK_Mode Off could complete no SPARK_Mode in a generic, either
4551 -- as specified in source code, or because SPARK_Mode On is ignored
4552 -- in an instance where the context is SPARK_Mode Off/Auto.
4554 elsif Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = Off
4555 and then (Is_Generic_Unit (Spec_Id) or else In_Instance)
4560 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4561 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4562 Error_Msg_Sloc := Sloc (Spec_Id);
4564 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4568 -- A subprogram body freezes its own contract. Analyze the contract
4569 -- after the declarations of the body have been processed as pragmas
4570 -- are now chained on the contract of the subprogram body.
4572 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4574 -- Check completion, and analyze the statements
4577 Inspect_Deferred_Constant_Completion (Declarations (N));
4580 -- Add the generated minimum accessibility objects to the subprogram
4581 -- body's list of declarations after analysis of the statements and
4584 while Is_Non_Empty_List (Minimum_Acc_Objs) loop
4585 if Present (Declarations (Body_Nod)) then
4586 Prepend (Remove_Head (Minimum_Acc_Objs), Declarations (Body_Nod));
4589 (Body_Nod, New_List (Remove_Head (Minimum_Acc_Objs)));
4593 -- Deal with end of scope processing for the body
4595 Process_End_Label (HSS, 't', Current_Scope);
4596 Update_Use_Clause_Chain;
4599 -- If we are compiling an entry wrapper, remove the enclosing
4600 -- synchronized object from the stack.
4602 if Is_Entry_Wrapper (Body_Id) then
4606 Check_Subprogram_Order (N);
4607 Set_Analyzed (Body_Id);
4609 -- If we have a separate spec, then the analysis of the declarations
4610 -- caused the entities in the body to be chained to the spec id, but
4611 -- we want them chained to the body id. Only the formal parameters
4612 -- end up chained to the spec id in this case.
4614 if Present (Spec_Id) then
4616 -- We must conform to the categorization of our spec
4618 Validate_Categorization_Dependency (N, Spec_Id);
4620 -- And if this is a child unit, the parent units must conform
4622 if Is_Child_Unit (Spec_Id) then
4623 Validate_Categorization_Dependency
4624 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4627 -- Here is where we move entities from the spec to the body
4629 -- Case where there are entities that stay with the spec
4631 if Present (Last_Real_Spec_Entity) then
4633 -- No body entities (happens when the only real spec entities come
4634 -- from precondition and postcondition pragmas).
4636 if No (Last_Entity (Body_Id)) then
4637 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4639 -- Body entities present (formals), so chain stuff past them
4643 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4646 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4647 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4648 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4650 -- Case where there are no spec entities, in this case there can be
4651 -- no body entities either, so just move everything.
4653 -- If the body is generated for an expression function, it may have
4654 -- been preanalyzed already, if 'access was applied to it.
4657 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4658 N_Expression_Function
4660 pragma Assert (No (Last_Entity (Body_Id)));
4664 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4665 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4666 Set_First_Entity (Spec_Id, Empty);
4667 Set_Last_Entity (Spec_Id, Empty);
4670 -- Otherwise the body does not complete a previous declaration. Check
4671 -- the categorization of the body against the units it withs.
4674 Validate_Categorization_Dependency (N, Body_Id);
4677 Check_Missing_Return;
4679 -- Now we are going to check for variables that are never modified in
4680 -- the body of the procedure. But first we deal with a special case
4681 -- where we want to modify this check. If the body of the subprogram
4682 -- starts with a raise statement or its equivalent, or if the body
4683 -- consists entirely of a null statement, then it is pretty obvious that
4684 -- it is OK to not reference the parameters. For example, this might be
4685 -- the following common idiom for a stubbed function: statement of the
4686 -- procedure raises an exception. In particular this deals with the
4687 -- common idiom of a stubbed function, which appears something like:
4689 -- function F (A : Integer) return Some_Type;
4692 -- raise Program_Error;
4696 -- Here the purpose of X is simply to satisfy the annoying requirement
4697 -- in Ada that there be at least one return, and we certainly do not
4698 -- want to go posting warnings on X that it is not initialized. On
4699 -- the other hand, if X is entirely unreferenced that should still
4702 -- What we do is to detect these cases, and if we find them, flag the
4703 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4704 -- suppress unwanted warnings. For the case of the function stub above
4705 -- we have a special test to set X as apparently assigned to suppress
4712 -- Skip call markers installed by the ABE mechanism, labels, and
4713 -- Push_xxx_Error_Label to find the first real statement.
4715 Stm := First (Statements (HSS));
4716 while Nkind_In (Stm, N_Call_Marker, N_Label)
4717 or else Nkind (Stm) in N_Push_xxx_Label
4722 -- Do the test on the original statement before expansion
4725 Ostm : constant Node_Id := Original_Node (Stm);
4728 -- If explicit raise statement, turn on flag
4730 if Nkind (Ostm) = N_Raise_Statement then
4731 Set_Trivial_Subprogram (Stm);
4733 -- If null statement, and no following statements, turn on flag
4735 elsif Nkind (Stm) = N_Null_Statement
4736 and then Comes_From_Source (Stm)
4737 and then No (Next (Stm))
4739 Set_Trivial_Subprogram (Stm);
4741 -- Check for explicit call cases which likely raise an exception
4743 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4744 if Is_Entity_Name (Name (Ostm)) then
4746 Ent : constant Entity_Id := Entity (Name (Ostm));
4749 -- If the procedure is marked No_Return, then likely it
4750 -- raises an exception, but in any case it is not coming
4751 -- back here, so turn on the flag.
4754 and then Ekind (Ent) = E_Procedure
4755 and then No_Return (Ent)
4757 Set_Trivial_Subprogram (Stm);
4765 -- Check for variables that are never modified
4772 -- If there is a separate spec, then transfer Never_Set_In_Source
4773 -- flags from out parameters to the corresponding entities in the
4774 -- body. The reason we do that is we want to post error flags on
4775 -- the body entities, not the spec entities.
4777 if Present (Spec_Id) then
4778 E1 := First_Entity (Spec_Id);
4779 while Present (E1) loop
4780 if Ekind (E1) = E_Out_Parameter then
4781 E2 := First_Entity (Body_Id);
4782 while Present (E2) loop
4783 exit when Chars (E1) = Chars (E2);
4787 if Present (E2) then
4788 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4796 -- Check references of the subprogram spec when we are dealing with
4797 -- an expression function due to it having a generated body.
4798 -- Otherwise, we simply check the formals of the subprogram body.
4800 if Present (Spec_Id)
4801 and then Is_Expression_Function (Spec_Id)
4803 Check_References (Spec_Id);
4805 Check_References (Body_Id);
4809 -- Check for nested subprogram, and mark outer level subprogram if so
4815 if Present (Spec_Id) then
4822 Ent := Enclosing_Subprogram (Ent);
4823 exit when No (Ent) or else Is_Subprogram (Ent);
4826 if Present (Ent) then
4827 Set_Has_Nested_Subprogram (Ent);
4831 -- Restore the limited views in the spec, if any, to let the back end
4832 -- process it without running into circularities.
4834 if Exch_Views /= No_Elist then
4835 Restore_Limited_Views (Exch_Views);
4838 if Mask_Types /= No_Elist then
4839 Unmask_Unfrozen_Types (Mask_Types);
4842 if Present (Desig_View) then
4843 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4847 if Present (Ignored_Ghost_Region) then
4848 Expander_Active := Saved_EA;
4851 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4852 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4853 end Analyze_Subprogram_Body_Helper;
4855 ------------------------------------
4856 -- Analyze_Subprogram_Declaration --
4857 ------------------------------------
4859 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4860 Scop : constant Entity_Id := Current_Scope;
4861 Designator : Entity_Id;
4863 Is_Completion : Boolean;
4864 -- Indicates whether a null procedure declaration is a completion
4867 -- Null procedures are not allowed in SPARK
4869 if Nkind (Specification (N)) = N_Procedure_Specification
4870 and then Null_Present (Specification (N))
4872 -- Null procedures are allowed in protected types, following the
4873 -- recent AI12-0147.
4875 if Is_Protected_Type (Current_Scope)
4876 and then Ada_Version < Ada_2012
4878 Error_Msg_N ("protected operation cannot be a null procedure", N);
4881 Analyze_Null_Procedure (N, Is_Completion);
4883 -- The null procedure acts as a body, nothing further is needed
4885 if Is_Completion then
4890 Designator := Analyze_Subprogram_Specification (Specification (N));
4892 -- A reference may already have been generated for the unit name, in
4893 -- which case the following call is redundant. However it is needed for
4894 -- declarations that are the rewriting of an expression function.
4896 Generate_Definition (Designator);
4898 -- Set the SPARK mode from the current context (may be overwritten later
4899 -- with explicit pragma). This is not done for entry barrier functions
4900 -- because they are generated outside the protected type and should not
4901 -- carry the mode of the enclosing context.
4903 if Nkind (N) = N_Subprogram_Declaration
4904 and then Is_Entry_Barrier_Function (N)
4909 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4910 Set_SPARK_Pragma_Inherited (Designator);
4913 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4914 -- the body of this subprogram is instantiated or inlined later and out
4915 -- of context. The body uses this attribute to restore the value of the
4918 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4919 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4922 -- Preserve relevant elaboration-related attributes of the context which
4923 -- are no longer available or very expensive to recompute once analysis,
4924 -- resolution, and expansion are over.
4926 Mark_Elaboration_Attributes
4927 (N_Id => Designator,
4931 if Debug_Flag_C then
4932 Write_Str ("==> subprogram spec ");
4933 Write_Name (Chars (Designator));
4934 Write_Str (" from ");
4935 Write_Location (Sloc (N));
4940 Validate_RCI_Subprogram_Declaration (N);
4941 New_Overloaded_Entity (Designator);
4942 Check_Delayed_Subprogram (Designator);
4944 -- If the type of the first formal of the current subprogram is a non-
4945 -- generic tagged private type, mark the subprogram as being a private
4946 -- primitive. Ditto if this is a function with controlling result, and
4947 -- the return type is currently private. In both cases, the type of the
4948 -- controlling argument or result must be in the current scope for the
4949 -- operation to be primitive.
4951 if Has_Controlling_Result (Designator)
4952 and then Is_Private_Type (Etype (Designator))
4953 and then Scope (Etype (Designator)) = Current_Scope
4954 and then not Is_Generic_Actual_Type (Etype (Designator))
4956 Set_Is_Private_Primitive (Designator);
4958 elsif Present (First_Formal (Designator)) then
4960 Formal_Typ : constant Entity_Id :=
4961 Etype (First_Formal (Designator));
4963 Set_Is_Private_Primitive (Designator,
4964 Is_Tagged_Type (Formal_Typ)
4965 and then Scope (Formal_Typ) = Current_Scope
4966 and then Is_Private_Type (Formal_Typ)
4967 and then not Is_Generic_Actual_Type (Formal_Typ));
4971 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4974 if Ada_Version >= Ada_2005
4975 and then Comes_From_Source (N)
4976 and then Is_Dispatching_Operation (Designator)
4983 if Has_Controlling_Result (Designator) then
4984 Etyp := Etype (Designator);
4987 E := First_Entity (Designator);
4989 and then Is_Formal (E)
4990 and then not Is_Controlling_Formal (E)
4998 if Is_Access_Type (Etyp) then
4999 Etyp := Directly_Designated_Type (Etyp);
5002 if Is_Interface (Etyp)
5003 and then not Is_Abstract_Subprogram (Designator)
5004 and then not (Ekind (Designator) = E_Procedure
5005 and then Null_Present (Specification (N)))
5007 Error_Msg_Name_1 := Chars (Defining_Entity (N));
5009 -- Specialize error message based on procedures vs. functions,
5010 -- since functions can't be null subprograms.
5012 if Ekind (Designator) = E_Procedure then
5014 ("interface procedure % must be abstract or null", N);
5017 ("interface function % must be abstract", N);
5023 -- What is the following code for, it used to be
5025 -- ??? Set_Suppress_Elaboration_Checks
5026 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
5028 -- The following seems equivalent, but a bit dubious
5030 if Elaboration_Checks_Suppressed (Designator) then
5031 Set_Kill_Elaboration_Checks (Designator);
5034 -- For a compilation unit, set body required. This flag will only be
5035 -- reset if a valid Import or Interface pragma is processed later on.
5037 if Nkind (Parent (N)) = N_Compilation_Unit then
5038 Set_Body_Required (Parent (N), True);
5040 if Ada_Version >= Ada_2005
5041 and then Nkind (Specification (N)) = N_Procedure_Specification
5042 and then Null_Present (Specification (N))
5045 ("null procedure cannot be declared at library level", N);
5049 Generate_Reference_To_Formals (Designator);
5050 Check_Eliminated (Designator);
5052 if Debug_Flag_C then
5054 Write_Str ("<== subprogram spec ");
5055 Write_Name (Chars (Designator));
5056 Write_Str (" from ");
5057 Write_Location (Sloc (N));
5061 -- Indicate that this is a protected operation, because it may be used
5062 -- in subsequent declarations within the protected type.
5064 if Is_Protected_Type (Current_Scope) then
5065 Set_Convention (Designator, Convention_Protected);
5068 List_Inherited_Pre_Post_Aspects (Designator);
5070 -- Process the aspects before establishing the proper categorization in
5071 -- case the subprogram is a compilation unit and one of its aspects is
5072 -- converted into a categorization pragma.
5074 if Has_Aspects (N) then
5075 Analyze_Aspect_Specifications (N, Designator);
5078 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
5079 Set_Categorization_From_Scope (Designator, Scop);
5081 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
5082 -- proper categorization of the unit based on its pragmas.
5085 Push_Scope (Designator);
5086 Set_Categorization_From_Pragmas (N);
5087 Validate_Categorization_Dependency (N, Designator);
5090 end Analyze_Subprogram_Declaration;
5092 --------------------------------------
5093 -- Analyze_Subprogram_Specification --
5094 --------------------------------------
5096 -- Reminder: N here really is a subprogram specification (not a subprogram
5097 -- declaration). This procedure is called to analyze the specification in
5098 -- both subprogram bodies and subprogram declarations (specs).
5100 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
5101 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
5102 -- Determine whether entity E denotes the spec or body of an invariant
5105 ------------------------------------
5106 -- Is_Invariant_Procedure_Or_Body --
5107 ------------------------------------
5109 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
5110 Decl : constant Node_Id := Unit_Declaration_Node (E);
5114 if Nkind (Decl) = N_Subprogram_Body then
5115 Spec := Corresponding_Spec (Decl);
5122 and then Ekind (Spec) = E_Procedure
5123 and then (Is_Partial_Invariant_Procedure (Spec)
5124 or else Is_Invariant_Procedure (Spec));
5125 end Is_Invariant_Procedure_Or_Body;
5129 Designator : constant Entity_Id := Defining_Entity (N);
5130 Formals : constant List_Id := Parameter_Specifications (N);
5132 -- Start of processing for Analyze_Subprogram_Specification
5135 -- Proceed with analysis. Do not emit a cross-reference entry if the
5136 -- specification comes from an expression function, because it may be
5137 -- the completion of a previous declaration. If it is not, the cross-
5138 -- reference entry will be emitted for the new subprogram declaration.
5140 if Nkind (Parent (N)) /= N_Expression_Function then
5141 Generate_Definition (Designator);
5144 if Nkind (N) = N_Function_Specification then
5145 Set_Ekind (Designator, E_Function);
5146 Set_Mechanism (Designator, Default_Mechanism);
5148 Set_Ekind (Designator, E_Procedure);
5149 Set_Etype (Designator, Standard_Void_Type);
5152 -- Flag Is_Inlined_Always is True by default, and reversed to False for
5153 -- those subprograms which could be inlined in GNATprove mode (because
5154 -- Body_To_Inline is non-Empty) but should not be inlined.
5156 if GNATprove_Mode then
5157 Set_Is_Inlined_Always (Designator);
5160 -- Introduce new scope for analysis of the formals and the return type
5162 Set_Scope (Designator, Current_Scope);
5164 if Present (Formals) then
5165 Push_Scope (Designator);
5166 Process_Formals (Formals, N);
5168 -- Check dimensions in N for formals with default expression
5170 Analyze_Dimension_Formals (N, Formals);
5172 -- Ada 2005 (AI-345): If this is an overriding operation of an
5173 -- inherited interface operation, and the controlling type is
5174 -- a synchronized type, replace the type with its corresponding
5175 -- record, to match the proper signature of an overriding operation.
5176 -- Same processing for an access parameter whose designated type is
5177 -- derived from a synchronized interface.
5179 -- This modification is not done for invariant procedures because
5180 -- the corresponding record may not necessarely be visible when the
5181 -- concurrent type acts as the full view of a private type.
5184 -- type Prot is private with Type_Invariant => ...;
5185 -- procedure ConcInvariant (Obj : Prot);
5187 -- protected type Prot is ...;
5188 -- type Concurrent_Record_Prot is record ...;
5189 -- procedure ConcInvariant (Obj : Prot) is
5191 -- end ConcInvariant;
5194 -- In the example above, both the spec and body of the invariant
5195 -- procedure must utilize the private type as the controlling type.
5197 if Ada_Version >= Ada_2005
5198 and then not Is_Invariant_Procedure_Or_Body (Designator)
5202 Formal_Typ : Entity_Id;
5203 Rec_Typ : Entity_Id;
5204 Desig_Typ : Entity_Id;
5207 Formal := First_Formal (Designator);
5208 while Present (Formal) loop
5209 Formal_Typ := Etype (Formal);
5211 if Is_Concurrent_Type (Formal_Typ)
5212 and then Present (Corresponding_Record_Type (Formal_Typ))
5214 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5216 if Present (Interfaces (Rec_Typ)) then
5217 Set_Etype (Formal, Rec_Typ);
5220 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5221 Desig_Typ := Designated_Type (Formal_Typ);
5223 if Is_Concurrent_Type (Desig_Typ)
5224 and then Present (Corresponding_Record_Type (Desig_Typ))
5226 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5228 if Present (Interfaces (Rec_Typ)) then
5229 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5234 Next_Formal (Formal);
5241 -- The subprogram scope is pushed and popped around the processing of
5242 -- the return type for consistency with call above to Process_Formals
5243 -- (which itself can call Analyze_Return_Type), and to ensure that any
5244 -- itype created for the return type will be associated with the proper
5247 elsif Nkind (N) = N_Function_Specification then
5248 Push_Scope (Designator);
5249 Analyze_Return_Type (N);
5255 if Nkind (N) = N_Function_Specification then
5257 -- Deal with operator symbol case
5259 if Nkind (Designator) = N_Defining_Operator_Symbol then
5260 Valid_Operator_Definition (Designator);
5263 May_Need_Actuals (Designator);
5265 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5266 -- the subprogram is abstract also. This does not apply to renaming
5267 -- declarations, where abstractness is inherited, and to subprogram
5268 -- bodies generated for stream operations, which become renamings as
5271 -- In case of primitives associated with abstract interface types
5272 -- the check is applied later (see Analyze_Subprogram_Declaration).
5274 if not Nkind_In (Original_Node (Parent (N)),
5275 N_Abstract_Subprogram_Declaration,
5276 N_Formal_Abstract_Subprogram_Declaration,
5277 N_Subprogram_Renaming_Declaration)
5279 if Is_Abstract_Type (Etype (Designator))
5280 and then not Is_Interface (Etype (Designator))
5283 ("function that returns abstract type must be abstract", N);
5285 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5286 -- access result whose designated type is abstract.
5288 elsif Ada_Version >= Ada_2012
5289 and then Nkind (Result_Definition (N)) = N_Access_Definition
5291 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5292 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5295 ("function whose access result designates abstract type "
5296 & "must be abstract", N);
5302 end Analyze_Subprogram_Specification;
5304 -----------------------
5305 -- Check_Conformance --
5306 -----------------------
5308 procedure Check_Conformance
5309 (New_Id : Entity_Id;
5311 Ctype : Conformance_Type;
5313 Conforms : out Boolean;
5314 Err_Loc : Node_Id := Empty;
5315 Get_Inst : Boolean := False;
5316 Skip_Controlling_Formals : Boolean := False)
5318 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5319 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5320 -- If Errmsg is True, then processing continues to post an error message
5321 -- for conformance error on given node. Two messages are output. The
5322 -- first message points to the previous declaration with a general "no
5323 -- conformance" message. The second is the detailed reason, supplied as
5324 -- Msg. The parameter N provide information for a possible & insertion
5325 -- in the message, and also provides the location for posting the
5326 -- message in the absence of a specified Err_Loc location.
5328 function Conventions_Match
5330 Id2 : Entity_Id) return Boolean;
5331 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5334 -----------------------
5335 -- Conformance_Error --
5336 -----------------------
5338 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5345 if No (Err_Loc) then
5351 Error_Msg_Sloc := Sloc (Old_Id);
5354 when Type_Conformant =>
5355 Error_Msg_N -- CODEFIX
5356 ("not type conformant with declaration#!", Enode);
5358 when Mode_Conformant =>
5359 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5361 ("not mode conformant with operation inherited#!",
5365 ("not mode conformant with declaration#!", Enode);
5368 when Subtype_Conformant =>
5369 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5371 ("not subtype conformant with operation inherited#!",
5375 ("not subtype conformant with declaration#!", Enode);
5378 when Fully_Conformant =>
5379 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5380 Error_Msg_N -- CODEFIX
5381 ("not fully conformant with operation inherited#!",
5384 Error_Msg_N -- CODEFIX
5385 ("not fully conformant with declaration#!", Enode);
5389 Error_Msg_NE (Msg, Enode, N);
5391 end Conformance_Error;
5393 -----------------------
5394 -- Conventions_Match --
5395 -----------------------
5397 function Conventions_Match
5399 Id2 : Entity_Id) return Boolean
5402 -- Ignore the conventions of anonymous access-to-subprogram types
5403 -- and subprogram types because these are internally generated and
5404 -- the only way these may receive a convention is if they inherit
5405 -- the convention of a related subprogram.
5407 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5410 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5415 -- Otherwise compare the conventions directly
5418 return Convention (Id1) = Convention (Id2);
5420 end Conventions_Match;
5424 Old_Type : constant Entity_Id := Etype (Old_Id);
5425 New_Type : constant Entity_Id := Etype (New_Id);
5426 Old_Formal : Entity_Id;
5427 New_Formal : Entity_Id;
5428 Access_Types_Match : Boolean;
5429 Old_Formal_Base : Entity_Id;
5430 New_Formal_Base : Entity_Id;
5432 -- Start of processing for Check_Conformance
5437 -- We need a special case for operators, since they don't appear
5440 if Ctype = Type_Conformant then
5441 if Ekind (New_Id) = E_Operator
5442 and then Operator_Matches_Spec (New_Id, Old_Id)
5448 -- If both are functions/operators, check return types conform
5450 if Old_Type /= Standard_Void_Type
5452 New_Type /= Standard_Void_Type
5454 -- If we are checking interface conformance we omit controlling
5455 -- arguments and result, because we are only checking the conformance
5456 -- of the remaining parameters.
5458 if Has_Controlling_Result (Old_Id)
5459 and then Has_Controlling_Result (New_Id)
5460 and then Skip_Controlling_Formals
5464 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5465 if Ctype >= Subtype_Conformant
5466 and then not Predicates_Match (Old_Type, New_Type)
5469 ("\predicate of return type does not match!", New_Id);
5472 ("\return type does not match!", New_Id);
5478 -- Ada 2005 (AI-231): In case of anonymous access types check the
5479 -- null-exclusion and access-to-constant attributes match.
5481 if Ada_Version >= Ada_2005
5482 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5484 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5485 or else Is_Access_Constant (Etype (Old_Type)) /=
5486 Is_Access_Constant (Etype (New_Type)))
5488 Conformance_Error ("\return type does not match!", New_Id);
5492 -- If either is a function/operator and the other isn't, error
5494 elsif Old_Type /= Standard_Void_Type
5495 or else New_Type /= Standard_Void_Type
5497 Conformance_Error ("\functions can only match functions!", New_Id);
5501 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5502 -- If this is a renaming as body, refine error message to indicate that
5503 -- the conflict is with the original declaration. If the entity is not
5504 -- frozen, the conventions don't have to match, the one of the renamed
5505 -- entity is inherited.
5507 if Ctype >= Subtype_Conformant then
5508 if not Conventions_Match (Old_Id, New_Id) then
5509 if not Is_Frozen (New_Id) then
5512 elsif Present (Err_Loc)
5513 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5514 and then Present (Corresponding_Spec (Err_Loc))
5516 Error_Msg_Name_1 := Chars (New_Id);
5518 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5519 Conformance_Error ("\prior declaration for% has convention %!");
5522 Conformance_Error ("\calling conventions do not match!");
5527 elsif Is_Formal_Subprogram (Old_Id)
5528 or else Is_Formal_Subprogram (New_Id)
5529 or else (Is_Subprogram (New_Id)
5530 and then Present (Alias (New_Id))
5531 and then Is_Formal_Subprogram (Alias (New_Id)))
5534 ("\formal subprograms are not subtype conformant "
5535 & "(RM 6.3.1 (17/3))");
5539 -- Deal with parameters
5541 -- Note: we use the entity information, rather than going directly
5542 -- to the specification in the tree. This is not only simpler, but
5543 -- absolutely necessary for some cases of conformance tests between
5544 -- operators, where the declaration tree simply does not exist.
5546 Old_Formal := First_Formal (Old_Id);
5547 New_Formal := First_Formal (New_Id);
5548 while Present (Old_Formal) and then Present (New_Formal) loop
5549 if Is_Controlling_Formal (Old_Formal)
5550 and then Is_Controlling_Formal (New_Formal)
5551 and then Skip_Controlling_Formals
5553 -- The controlling formals will have different types when
5554 -- comparing an interface operation with its match, but both
5555 -- or neither must be access parameters.
5557 if Is_Access_Type (Etype (Old_Formal))
5559 Is_Access_Type (Etype (New_Formal))
5561 goto Skip_Controlling_Formal;
5564 ("\access parameter does not match!", New_Formal);
5568 -- Ada 2012: Mode conformance also requires that formal parameters
5569 -- be both aliased, or neither.
5571 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5572 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5574 ("\aliased parameter mismatch!", New_Formal);
5578 if Ctype = Fully_Conformant then
5580 -- Names must match. Error message is more accurate if we do
5581 -- this before checking that the types of the formals match.
5583 if Chars (Old_Formal) /= Chars (New_Formal) then
5584 Conformance_Error ("\name& does not match!", New_Formal);
5586 -- Set error posted flag on new formal as well to stop
5587 -- junk cascaded messages in some cases.
5589 Set_Error_Posted (New_Formal);
5593 -- Null exclusion must match
5595 if Null_Exclusion_Present (Parent (Old_Formal))
5597 Null_Exclusion_Present (Parent (New_Formal))
5599 -- Only give error if both come from source. This should be
5600 -- investigated some time, since it should not be needed ???
5602 if Comes_From_Source (Old_Formal)
5604 Comes_From_Source (New_Formal)
5607 ("\null exclusion for& does not match", New_Formal);
5609 -- Mark error posted on the new formal to avoid duplicated
5610 -- complaint about types not matching.
5612 Set_Error_Posted (New_Formal);
5617 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5618 -- case occurs whenever a subprogram is being renamed and one of its
5619 -- parameters imposes a null exclusion. For example:
5621 -- type T is null record;
5622 -- type Acc_T is access T;
5623 -- subtype Acc_T_Sub is Acc_T;
5625 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5626 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5629 Old_Formal_Base := Etype (Old_Formal);
5630 New_Formal_Base := Etype (New_Formal);
5633 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5634 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5637 Access_Types_Match := Ada_Version >= Ada_2005
5639 -- Ensure that this rule is only applied when New_Id is a
5640 -- renaming of Old_Id.
5642 and then Nkind (Parent (Parent (New_Id))) =
5643 N_Subprogram_Renaming_Declaration
5644 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5645 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5646 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5648 -- Now handle the allowed access-type case
5650 and then Is_Access_Type (Old_Formal_Base)
5651 and then Is_Access_Type (New_Formal_Base)
5653 -- The type kinds must match. The only exception occurs with
5654 -- multiple generics of the form:
5657 -- type F is private; type A is private;
5658 -- type F_Ptr is access F; type A_Ptr is access A;
5659 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5660 -- package F_Pack is ... package A_Pack is
5661 -- package F_Inst is
5662 -- new F_Pack (A, A_Ptr, A_P);
5664 -- When checking for conformance between the parameters of A_P
5665 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5666 -- because the compiler has transformed A_Ptr into a subtype of
5667 -- F_Ptr. We catch this case in the code below.
5669 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5671 (Is_Generic_Type (Old_Formal_Base)
5672 and then Is_Generic_Type (New_Formal_Base)
5673 and then Is_Internal (New_Formal_Base)
5674 and then Etype (Etype (New_Formal_Base)) =
5676 and then Directly_Designated_Type (Old_Formal_Base) =
5677 Directly_Designated_Type (New_Formal_Base)
5678 and then ((Is_Itype (Old_Formal_Base)
5679 and then (Can_Never_Be_Null (Old_Formal_Base)
5680 or else Is_Access_Constant
5683 (Is_Itype (New_Formal_Base)
5684 and then (Can_Never_Be_Null (New_Formal_Base)
5685 or else Is_Access_Constant
5686 (New_Formal_Base))));
5688 -- Types must always match. In the visible part of an instance,
5689 -- usual overloading rules for dispatching operations apply, and
5690 -- we check base types (not the actual subtypes).
5692 if In_Instance_Visible_Part
5693 and then Is_Dispatching_Operation (New_Id)
5695 if not Conforming_Types
5696 (T1 => Base_Type (Etype (Old_Formal)),
5697 T2 => Base_Type (Etype (New_Formal)),
5699 Get_Inst => Get_Inst)
5700 and then not Access_Types_Match
5702 Conformance_Error ("\type of & does not match!", New_Formal);
5706 elsif not Conforming_Types
5707 (T1 => Old_Formal_Base,
5708 T2 => New_Formal_Base,
5710 Get_Inst => Get_Inst)
5711 and then not Access_Types_Match
5713 -- Don't give error message if old type is Any_Type. This test
5714 -- avoids some cascaded errors, e.g. in case of a bad spec.
5716 if Errmsg and then Old_Formal_Base = Any_Type then
5719 if Ctype >= Subtype_Conformant
5721 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5724 ("\predicate of & does not match!", New_Formal);
5727 ("\type of & does not match!", New_Formal);
5729 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5731 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5739 -- For mode conformance, mode must match
5741 if Ctype >= Mode_Conformant then
5742 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5743 if not Ekind_In (New_Id, E_Function, E_Procedure)
5744 or else not Is_Primitive_Wrapper (New_Id)
5746 Conformance_Error ("\mode of & does not match!", New_Formal);
5750 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5752 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5754 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5757 ("\mode of & does not match!", New_Formal);
5764 -- Part of mode conformance for access types is having the same
5765 -- constant modifier.
5767 elsif Access_Types_Match
5768 and then Is_Access_Constant (Old_Formal_Base) /=
5769 Is_Access_Constant (New_Formal_Base)
5772 ("\constant modifier does not match!", New_Formal);
5777 if Ctype >= Subtype_Conformant then
5779 -- Ada 2005 (AI-231): In case of anonymous access types check
5780 -- the null-exclusion and access-to-constant attributes must
5781 -- match. For null exclusion, we test the types rather than the
5782 -- formals themselves, since the attribute is only set reliably
5783 -- on the formals in the Ada 95 case, and we exclude the case
5784 -- where Old_Formal is marked as controlling, to avoid errors
5785 -- when matching completing bodies with dispatching declarations
5786 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5788 if Ada_Version >= Ada_2005
5789 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5790 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5792 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5793 Can_Never_Be_Null (Etype (New_Formal))
5795 not Is_Controlling_Formal (Old_Formal))
5797 Is_Access_Constant (Etype (Old_Formal)) /=
5798 Is_Access_Constant (Etype (New_Formal)))
5800 -- Do not complain if error already posted on New_Formal. This
5801 -- avoids some redundant error messages.
5803 and then not Error_Posted (New_Formal)
5805 -- It is allowed to omit the null-exclusion in case of stream
5806 -- attribute subprograms. We recognize stream subprograms
5807 -- through their TSS-generated suffix.
5810 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5813 if TSS_Name /= TSS_Stream_Read
5814 and then TSS_Name /= TSS_Stream_Write
5815 and then TSS_Name /= TSS_Stream_Input
5816 and then TSS_Name /= TSS_Stream_Output
5818 -- Here we have a definite conformance error. It is worth
5819 -- special casing the error message for the case of a
5820 -- controlling formal (which excludes null).
5822 if Is_Controlling_Formal (New_Formal) then
5823 Error_Msg_Node_2 := Scope (New_Formal);
5825 ("\controlling formal & of & excludes null, "
5826 & "declaration must exclude null as well",
5829 -- Normal case (couldn't we give more detail here???)
5833 ("\type of & does not match!", New_Formal);
5842 -- Full conformance checks
5844 if Ctype = Fully_Conformant then
5846 -- We have checked already that names match
5848 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5850 -- Check default expressions for in parameters
5853 NewD : constant Boolean :=
5854 Present (Default_Value (New_Formal));
5855 OldD : constant Boolean :=
5856 Present (Default_Value (Old_Formal));
5858 if NewD or OldD then
5860 -- The old default value has been analyzed because the
5861 -- current full declaration will have frozen everything
5862 -- before. The new default value has not been analyzed,
5863 -- so analyze it now before we check for conformance.
5866 Push_Scope (New_Id);
5867 Preanalyze_Spec_Expression
5868 (Default_Value (New_Formal), Etype (New_Formal));
5872 if not (NewD and OldD)
5873 or else not Fully_Conformant_Expressions
5874 (Default_Value (Old_Formal),
5875 Default_Value (New_Formal))
5878 ("\default expression for & does not match!",
5887 -- A couple of special checks for Ada 83 mode. These checks are
5888 -- skipped if either entity is an operator in package Standard,
5889 -- or if either old or new instance is not from the source program.
5891 if Ada_Version = Ada_83
5892 and then Sloc (Old_Id) > Standard_Location
5893 and then Sloc (New_Id) > Standard_Location
5894 and then Comes_From_Source (Old_Id)
5895 and then Comes_From_Source (New_Id)
5898 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5899 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5902 -- Explicit IN must be present or absent in both cases. This
5903 -- test is required only in the full conformance case.
5905 if In_Present (Old_Param) /= In_Present (New_Param)
5906 and then Ctype = Fully_Conformant
5909 ("\(Ada 83) IN must appear in both declarations",
5914 -- Grouping (use of comma in param lists) must be the same
5915 -- This is where we catch a misconformance like:
5918 -- A : Integer; B : Integer
5920 -- which are represented identically in the tree except
5921 -- for the setting of the flags More_Ids and Prev_Ids.
5923 if More_Ids (Old_Param) /= More_Ids (New_Param)
5924 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5927 ("\grouping of & does not match!", New_Formal);
5933 -- This label is required when skipping controlling formals
5935 <<Skip_Controlling_Formal>>
5937 Next_Formal (Old_Formal);
5938 Next_Formal (New_Formal);
5941 if Present (Old_Formal) then
5942 Conformance_Error ("\too few parameters!");
5945 elsif Present (New_Formal) then
5946 Conformance_Error ("\too many parameters!", New_Formal);
5949 end Check_Conformance;
5951 -----------------------
5952 -- Check_Conventions --
5953 -----------------------
5955 procedure Check_Conventions (Typ : Entity_Id) is
5956 Ifaces_List : Elist_Id;
5958 procedure Check_Convention (Op : Entity_Id);
5959 -- Verify that the convention of inherited dispatching operation Op is
5960 -- consistent among all subprograms it overrides. In order to minimize
5961 -- the search, Search_From is utilized to designate a specific point in
5962 -- the list rather than iterating over the whole list once more.
5964 ----------------------
5965 -- Check_Convention --
5966 ----------------------
5968 procedure Check_Convention (Op : Entity_Id) is
5969 Op_Conv : constant Convention_Id := Convention (Op);
5970 Iface_Conv : Convention_Id;
5971 Iface_Elmt : Elmt_Id;
5972 Iface_Prim_Elmt : Elmt_Id;
5973 Iface_Prim : Entity_Id;
5976 Iface_Elmt := First_Elmt (Ifaces_List);
5977 while Present (Iface_Elmt) loop
5979 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5980 while Present (Iface_Prim_Elmt) loop
5981 Iface_Prim := Node (Iface_Prim_Elmt);
5982 Iface_Conv := Convention (Iface_Prim);
5984 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5985 and then Iface_Conv /= Op_Conv
5988 ("inconsistent conventions in primitive operations", Typ);
5990 Error_Msg_Name_1 := Chars (Op);
5991 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5992 Error_Msg_Sloc := Sloc (Op);
5994 if Comes_From_Source (Op) or else No (Alias (Op)) then
5995 if not Present (Overridden_Operation (Op)) then
5996 Error_Msg_N ("\\primitive % defined #", Typ);
5999 ("\\overriding operation % with "
6000 & "convention % defined #", Typ);
6003 else pragma Assert (Present (Alias (Op)));
6004 Error_Msg_Sloc := Sloc (Alias (Op));
6005 Error_Msg_N ("\\inherited operation % with "
6006 & "convention % defined #", Typ);
6009 Error_Msg_Name_1 := Chars (Op);
6010 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
6011 Error_Msg_Sloc := Sloc (Iface_Prim);
6012 Error_Msg_N ("\\overridden operation % with "
6013 & "convention % defined #", Typ);
6015 -- Avoid cascading errors
6020 Next_Elmt (Iface_Prim_Elmt);
6023 Next_Elmt (Iface_Elmt);
6025 end Check_Convention;
6029 Prim_Op : Entity_Id;
6030 Prim_Op_Elmt : Elmt_Id;
6032 -- Start of processing for Check_Conventions
6035 if not Has_Interfaces (Typ) then
6039 Collect_Interfaces (Typ, Ifaces_List);
6041 -- The algorithm checks every overriding dispatching operation against
6042 -- all the corresponding overridden dispatching operations, detecting
6043 -- differences in conventions.
6045 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
6046 while Present (Prim_Op_Elmt) loop
6047 Prim_Op := Node (Prim_Op_Elmt);
6049 -- A small optimization: skip the predefined dispatching operations
6050 -- since they always have the same convention.
6052 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
6053 Check_Convention (Prim_Op);
6056 Next_Elmt (Prim_Op_Elmt);
6058 end Check_Conventions;
6060 ------------------------------
6061 -- Check_Delayed_Subprogram --
6062 ------------------------------
6064 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
6065 procedure Possible_Freeze (T : Entity_Id);
6066 -- T is the type of either a formal parameter or of the return type. If
6067 -- T is not yet frozen and needs a delayed freeze, then the subprogram
6068 -- itself must be delayed.
6070 ---------------------
6071 -- Possible_Freeze --
6072 ---------------------
6074 procedure Possible_Freeze (T : Entity_Id) is
6075 Scop : constant Entity_Id := Scope (Designator);
6078 -- If the subprogram appears within a package instance (which may be
6079 -- the wrapper package of a subprogram instance) the freeze node for
6080 -- that package will freeze the subprogram at the proper place, so
6081 -- do not emit a freeze node for the subprogram, given that it may
6082 -- appear in the wrong scope.
6084 if Ekind (Scop) = E_Package
6085 and then not Comes_From_Source (Scop)
6086 and then Is_Generic_Instance (Scop)
6090 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
6091 Set_Has_Delayed_Freeze (Designator);
6093 elsif Is_Access_Type (T)
6094 and then Has_Delayed_Freeze (Designated_Type (T))
6095 and then not Is_Frozen (Designated_Type (T))
6097 Set_Has_Delayed_Freeze (Designator);
6099 end Possible_Freeze;
6105 -- Start of processing for Check_Delayed_Subprogram
6108 -- All subprograms, including abstract subprograms, may need a freeze
6109 -- node if some formal type or the return type needs one.
6111 Possible_Freeze (Etype (Designator));
6112 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
6114 -- Need delayed freeze if any of the formal types themselves need a
6115 -- delayed freeze and are not yet frozen.
6117 F := First_Formal (Designator);
6118 while Present (F) loop
6119 Possible_Freeze (Etype (F));
6120 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
6124 -- Mark functions that return by reference. Note that it cannot be done
6125 -- for delayed_freeze subprograms because the underlying returned type
6126 -- may not be known yet (for private types).
6128 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
6130 Typ : constant Entity_Id := Etype (Designator);
6131 Utyp : constant Entity_Id := Underlying_Type (Typ);
6134 if Is_Limited_View (Typ) then
6135 Set_Returns_By_Ref (Designator);
6137 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
6138 Set_Returns_By_Ref (Designator);
6142 end Check_Delayed_Subprogram;
6144 ------------------------------------
6145 -- Check_Discriminant_Conformance --
6146 ------------------------------------
6148 procedure Check_Discriminant_Conformance
6153 Old_Discr : Entity_Id := First_Discriminant (Prev);
6154 New_Discr : Node_Id := First (Discriminant_Specifications (N));
6155 New_Discr_Id : Entity_Id;
6156 New_Discr_Type : Entity_Id;
6158 procedure Conformance_Error (Msg : String; N : Node_Id);
6159 -- Post error message for conformance error on given node. Two messages
6160 -- are output. The first points to the previous declaration with a
6161 -- general "no conformance" message. The second is the detailed reason,
6162 -- supplied as Msg. The parameter N provide information for a possible
6163 -- & insertion in the message.
6165 -----------------------
6166 -- Conformance_Error --
6167 -----------------------
6169 procedure Conformance_Error (Msg : String; N : Node_Id) is
6171 Error_Msg_Sloc := Sloc (Prev_Loc);
6172 Error_Msg_N -- CODEFIX
6173 ("not fully conformant with declaration#!", N);
6174 Error_Msg_NE (Msg, N, N);
6175 end Conformance_Error;
6177 -- Start of processing for Check_Discriminant_Conformance
6180 while Present (Old_Discr) and then Present (New_Discr) loop
6181 New_Discr_Id := Defining_Identifier (New_Discr);
6183 -- The subtype mark of the discriminant on the full type has not
6184 -- been analyzed so we do it here. For an access discriminant a new
6187 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
6189 Access_Definition (N, Discriminant_Type (New_Discr));
6192 Find_Type (Discriminant_Type (New_Discr));
6193 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6195 -- Ada 2005: if the discriminant definition carries a null
6196 -- exclusion, create an itype to check properly for consistency
6197 -- with partial declaration.
6199 if Is_Access_Type (New_Discr_Type)
6200 and then Null_Exclusion_Present (New_Discr)
6203 Create_Null_Excluding_Itype
6204 (T => New_Discr_Type,
6205 Related_Nod => New_Discr,
6206 Scope_Id => Current_Scope);
6210 if not Conforming_Types
6211 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6213 Conformance_Error ("type of & does not match!", New_Discr_Id);
6216 -- Treat the new discriminant as an occurrence of the old one,
6217 -- for navigation purposes, and fill in some semantic
6218 -- information, for completeness.
6220 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6221 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6222 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6227 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6228 Conformance_Error ("name & does not match!", New_Discr_Id);
6232 -- Default expressions must match
6235 NewD : constant Boolean :=
6236 Present (Expression (New_Discr));
6237 OldD : constant Boolean :=
6238 Present (Expression (Parent (Old_Discr)));
6241 if NewD or OldD then
6243 -- The old default value has been analyzed and expanded,
6244 -- because the current full declaration will have frozen
6245 -- everything before. The new default values have not been
6246 -- expanded, so expand now to check conformance.
6249 Preanalyze_Spec_Expression
6250 (Expression (New_Discr), New_Discr_Type);
6253 if not (NewD and OldD)
6254 or else not Fully_Conformant_Expressions
6255 (Expression (Parent (Old_Discr)),
6256 Expression (New_Discr))
6260 ("default expression for & does not match!",
6267 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6269 if Ada_Version = Ada_83 then
6271 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6274 -- Grouping (use of comma in param lists) must be the same
6275 -- This is where we catch a misconformance like:
6278 -- A : Integer; B : Integer
6280 -- which are represented identically in the tree except
6281 -- for the setting of the flags More_Ids and Prev_Ids.
6283 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6284 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6287 ("grouping of & does not match!", New_Discr_Id);
6293 Next_Discriminant (Old_Discr);
6297 if Present (Old_Discr) then
6298 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6301 elsif Present (New_Discr) then
6303 ("too many discriminants!", Defining_Identifier (New_Discr));
6306 end Check_Discriminant_Conformance;
6308 ----------------------------
6309 -- Check_Fully_Conformant --
6310 ----------------------------
6312 procedure Check_Fully_Conformant
6313 (New_Id : Entity_Id;
6315 Err_Loc : Node_Id := Empty)
6318 pragma Warnings (Off, Result);
6321 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6322 end Check_Fully_Conformant;
6324 --------------------------
6325 -- Check_Limited_Return --
6326 --------------------------
6328 procedure Check_Limited_Return
6334 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6335 -- replaced by anonymous access results. This is an incompatibility with
6336 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6337 -- controllable with special switch. ???
6339 -- A limited interface that is not immutably limited is OK
6341 if Is_Limited_Interface (R_Type)
6343 not (Is_Task_Interface (R_Type)
6344 or else Is_Protected_Interface (R_Type)
6345 or else Is_Synchronized_Interface (R_Type))
6349 elsif Is_Limited_Type (R_Type)
6350 and then not Is_Interface (R_Type)
6351 and then Comes_From_Source (N)
6352 and then not In_Instance_Body
6353 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6355 -- Error in Ada 2005
6357 if Ada_Version >= Ada_2005
6358 and then not Debug_Flag_Dot_L
6359 and then not GNAT_Mode
6362 ("(Ada 2005) cannot copy object of a limited type "
6363 & "(RM-2005 6.5(5.5/2))", Expr);
6365 if Is_Limited_View (R_Type) then
6367 ("\return by reference not permitted in Ada 2005", Expr);
6370 -- Warn in Ada 95 mode, to give folks a heads up about this
6373 -- In GNAT mode, this is just a warning, to allow it to be evilly
6374 -- turned off. Otherwise it is a real error.
6376 -- In a generic context, simplify the warning because it makes no
6377 -- sense to discuss pass-by-reference or copy.
6379 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6380 if Inside_A_Generic then
6382 ("return of limited object not permitted in Ada 2005 "
6383 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6385 elsif Is_Limited_View (R_Type) then
6387 ("return by reference not permitted in Ada 2005 "
6388 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6391 ("cannot copy object of a limited type in Ada 2005 "
6392 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6395 -- Ada 95 mode, and compatibility warnings disabled
6398 pragma Assert (Ada_Version <= Ada_95);
6399 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6400 return; -- skip continuation messages below
6403 if not Inside_A_Generic then
6405 ("\consider switching to return of access type", Expr);
6406 Explain_Limited_Type (R_Type, Expr);
6409 end Check_Limited_Return;
6411 ---------------------------
6412 -- Check_Mode_Conformant --
6413 ---------------------------
6415 procedure Check_Mode_Conformant
6416 (New_Id : Entity_Id;
6418 Err_Loc : Node_Id := Empty;
6419 Get_Inst : Boolean := False)
6422 pragma Warnings (Off, Result);
6425 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6426 end Check_Mode_Conformant;
6428 --------------------------------
6429 -- Check_Overriding_Indicator --
6430 --------------------------------
6432 procedure Check_Overriding_Indicator
6434 Overridden_Subp : Entity_Id;
6435 Is_Primitive : Boolean)
6441 -- No overriding indicator for literals
6443 if Ekind (Subp) = E_Enumeration_Literal then
6446 elsif Ekind (Subp) = E_Entry then
6447 Decl := Parent (Subp);
6449 -- No point in analyzing a malformed operator
6451 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6452 and then Error_Posted (Subp)
6457 Decl := Unit_Declaration_Node (Subp);
6460 if Nkind_In (Decl, N_Subprogram_Body,
6461 N_Subprogram_Body_Stub,
6462 N_Subprogram_Declaration,
6463 N_Abstract_Subprogram_Declaration,
6464 N_Subprogram_Renaming_Declaration)
6466 Spec := Specification (Decl);
6468 elsif Nkind (Decl) = N_Entry_Declaration then
6475 -- The overriding operation is type conformant with the overridden one,
6476 -- but the names of the formals are not required to match. If the names
6477 -- appear permuted in the overriding operation, this is a possible
6478 -- source of confusion that is worth diagnosing. Controlling formals
6479 -- often carry names that reflect the type, and it is not worthwhile
6480 -- requiring that their names match.
6482 if Present (Overridden_Subp)
6483 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6490 Form1 := First_Formal (Subp);
6491 Form2 := First_Formal (Overridden_Subp);
6493 -- If the overriding operation is a synchronized operation, skip
6494 -- the first parameter of the overridden operation, which is
6495 -- implicit in the new one. If the operation is declared in the
6496 -- body it is not primitive and all formals must match.
6498 if Is_Concurrent_Type (Scope (Subp))
6499 and then Is_Tagged_Type (Scope (Subp))
6500 and then not Has_Completion (Scope (Subp))
6502 Form2 := Next_Formal (Form2);
6505 if Present (Form1) then
6506 Form1 := Next_Formal (Form1);
6507 Form2 := Next_Formal (Form2);
6510 while Present (Form1) loop
6511 if not Is_Controlling_Formal (Form1)
6512 and then Present (Next_Formal (Form2))
6513 and then Chars (Form1) = Chars (Next_Formal (Form2))
6515 Error_Msg_Node_2 := Alias (Overridden_Subp);
6516 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6518 ("& does not match corresponding formal of&#",
6523 Next_Formal (Form1);
6524 Next_Formal (Form2);
6529 -- If there is an overridden subprogram, then check that there is no
6530 -- "not overriding" indicator, and mark the subprogram as overriding.
6532 -- This is not done if the overridden subprogram is marked as hidden,
6533 -- which can occur for the case of inherited controlled operations
6534 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6535 -- subprogram is not itself hidden or we are within a generic instance,
6536 -- in which case the hidden flag may have been modified for the
6537 -- expansion of the instance.
6539 -- (Note: This condition could probably be simplified, leaving out the
6540 -- testing for the specific controlled cases, but it seems safer and
6541 -- clearer this way, and echoes similar special-case tests of this
6542 -- kind in other places.)
6544 if Present (Overridden_Subp)
6545 and then (not Is_Hidden (Overridden_Subp)
6547 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6550 and then Present (Alias (Overridden_Subp))
6551 and then (not Is_Hidden (Alias (Overridden_Subp))
6552 or else In_Instance)))
6554 if Must_Not_Override (Spec) then
6555 Error_Msg_Sloc := Sloc (Overridden_Subp);
6557 if Ekind (Subp) = E_Entry then
6559 ("entry & overrides inherited operation #", Spec, Subp);
6562 ("subprogram & overrides inherited operation #", Spec, Subp);
6565 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6566 -- as an extension of Root_Controlled, and thus has a useless Adjust
6567 -- operation. This operation should not be inherited by other limited
6568 -- controlled types. An explicit Adjust for them is not overriding.
6570 elsif Must_Override (Spec)
6571 and then Chars (Overridden_Subp) = Name_Adjust
6572 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6573 and then Present (Alias (Overridden_Subp))
6574 and then In_Predefined_Unit (Alias (Overridden_Subp))
6577 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6578 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6580 elsif Is_Subprogram (Subp) then
6581 if Is_Init_Proc (Subp) then
6584 elsif No (Overridden_Operation (Subp)) then
6586 -- For entities generated by Derive_Subprograms the overridden
6587 -- operation is the inherited primitive (which is available
6588 -- through the attribute alias)
6590 if (Is_Dispatching_Operation (Subp)
6591 or else Is_Dispatching_Operation (Overridden_Subp))
6592 and then not Comes_From_Source (Overridden_Subp)
6593 and then Find_Dispatching_Type (Overridden_Subp) =
6594 Find_Dispatching_Type (Subp)
6595 and then Present (Alias (Overridden_Subp))
6596 and then Comes_From_Source (Alias (Overridden_Subp))
6598 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6599 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6602 Set_Overridden_Operation (Subp, Overridden_Subp);
6603 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6608 -- If primitive flag is set or this is a protected operation, then
6609 -- the operation is overriding at the point of its declaration, so
6610 -- warn if necessary. Otherwise it may have been declared before the
6611 -- operation it overrides and no check is required.
6614 and then not Must_Override (Spec)
6615 and then (Is_Primitive
6616 or else Ekind (Scope (Subp)) = E_Protected_Type)
6618 Style.Missing_Overriding (Decl, Subp);
6621 -- If Subp is an operator, it may override a predefined operation, if
6622 -- it is defined in the same scope as the type to which it applies.
6623 -- In that case Overridden_Subp is empty because of our implicit
6624 -- representation for predefined operators. We have to check whether the
6625 -- signature of Subp matches that of a predefined operator. Note that
6626 -- first argument provides the name of the operator, and the second
6627 -- argument the signature that may match that of a standard operation.
6628 -- If the indicator is overriding, then the operator must match a
6629 -- predefined signature, because we know already that there is no
6630 -- explicit overridden operation.
6632 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6633 if Must_Not_Override (Spec) then
6635 -- If this is not a primitive or a protected subprogram, then
6636 -- "not overriding" is illegal.
6639 and then Ekind (Scope (Subp)) /= E_Protected_Type
6641 Error_Msg_N ("overriding indicator only allowed "
6642 & "if subprogram is primitive", Subp);
6644 elsif Can_Override_Operator (Subp) then
6646 ("subprogram& overrides predefined operator ", Spec, Subp);
6649 elsif Must_Override (Spec) then
6650 if No (Overridden_Operation (Subp))
6651 and then not Can_Override_Operator (Subp)
6653 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6656 elsif not Error_Posted (Subp)
6657 and then Style_Check
6658 and then Can_Override_Operator (Subp)
6659 and then not In_Predefined_Unit (Subp)
6661 -- If style checks are enabled, indicate that the indicator is
6662 -- missing. However, at the point of declaration, the type of
6663 -- which this is a primitive operation may be private, in which
6664 -- case the indicator would be premature.
6666 if Has_Private_Declaration (Etype (Subp))
6667 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6671 Style.Missing_Overriding (Decl, Subp);
6675 elsif Must_Override (Spec) then
6676 if Ekind (Subp) = E_Entry then
6677 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6679 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6682 -- If the operation is marked "not overriding" and it's not primitive
6683 -- then an error is issued, unless this is an operation of a task or
6684 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6685 -- has been specified have already been checked above.
6687 elsif Must_Not_Override (Spec)
6688 and then not Is_Primitive
6689 and then Ekind (Subp) /= E_Entry
6690 and then Ekind (Scope (Subp)) /= E_Protected_Type
6693 ("overriding indicator only allowed if subprogram is primitive",
6697 end Check_Overriding_Indicator;
6703 -- Note: this procedure needs to know far too much about how the expander
6704 -- messes with exceptions. The use of the flag Exception_Junk and the
6705 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6706 -- works, but is not very clean. It would be better if the expansion
6707 -- routines would leave Original_Node working nicely, and we could use
6708 -- Original_Node here to ignore all the peculiar expander messing ???
6710 procedure Check_Returns
6714 Proc : Entity_Id := Empty)
6718 procedure Check_Statement_Sequence (L : List_Id);
6719 -- Internal recursive procedure to check a list of statements for proper
6720 -- termination by a return statement (or a transfer of control or a
6721 -- compound statement that is itself internally properly terminated).
6723 ------------------------------
6724 -- Check_Statement_Sequence --
6725 ------------------------------
6727 procedure Check_Statement_Sequence (L : List_Id) is
6732 function Assert_False return Boolean;
6733 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6734 -- rewritten as a null statement when assertions are off. The assert
6735 -- is not active, but it is still enough to kill the warning.
6741 function Assert_False return Boolean is
6742 Orig : constant Node_Id := Original_Node (Last_Stm);
6745 if Nkind (Orig) = N_Pragma
6746 and then Pragma_Name (Orig) = Name_Assert
6747 and then not Error_Posted (Orig)
6750 Arg : constant Node_Id :=
6751 First (Pragma_Argument_Associations (Orig));
6752 Exp : constant Node_Id := Expression (Arg);
6754 return Nkind (Exp) = N_Identifier
6755 and then Chars (Exp) = Name_False;
6765 Raise_Exception_Call : Boolean;
6766 -- Set True if statement sequence terminated by Raise_Exception call
6767 -- or a Reraise_Occurrence call.
6769 -- Start of processing for Check_Statement_Sequence
6772 Raise_Exception_Call := False;
6774 -- Get last real statement
6776 Last_Stm := Last (L);
6778 -- Deal with digging out exception handler statement sequences that
6779 -- have been transformed by the local raise to goto optimization.
6780 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6781 -- optimization has occurred, we are looking at something like:
6784 -- original stmts in block
6788 -- goto L1; | omitted if No_Exception_Propagation
6793 -- goto L3; -- skip handler when exception not raised
6795 -- <<L1>> -- target label for local exception
6809 -- and what we have to do is to dig out the estmts1 and estmts2
6810 -- sequences (which were the original sequences of statements in
6811 -- the exception handlers) and check them.
6813 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6818 exit when Nkind (Stm) /= N_Block_Statement;
6819 exit when not Exception_Junk (Stm);
6822 exit when Nkind (Stm) /= N_Label;
6823 exit when not Exception_Junk (Stm);
6824 Check_Statement_Sequence
6825 (Statements (Handled_Statement_Sequence (Next (Stm))));
6830 exit when Nkind (Stm) /= N_Goto_Statement;
6831 exit when not Exception_Junk (Stm);
6835 -- Don't count pragmas
6837 while Nkind (Last_Stm) = N_Pragma
6839 -- Don't count call to SS_Release (can happen after Raise_Exception)
6842 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6844 Nkind (Name (Last_Stm)) = N_Identifier
6846 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6848 -- Don't count exception junk
6851 (Nkind_In (Last_Stm, N_Goto_Statement,
6853 N_Object_Declaration)
6854 and then Exception_Junk (Last_Stm))
6855 or else Nkind (Last_Stm) in N_Push_xxx_Label
6856 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6858 -- Inserted code, such as finalization calls, is irrelevant: we only
6859 -- need to check original source.
6861 or else Is_Rewrite_Insertion (Last_Stm)
6866 -- Here we have the "real" last statement
6868 Kind := Nkind (Last_Stm);
6870 -- Transfer of control, OK. Note that in the No_Return procedure
6871 -- case, we already diagnosed any explicit return statements, so
6872 -- we can treat them as OK in this context.
6874 if Is_Transfer (Last_Stm) then
6877 -- Check cases of explicit non-indirect procedure calls
6879 elsif Kind = N_Procedure_Call_Statement
6880 and then Is_Entity_Name (Name (Last_Stm))
6882 -- Check call to Raise_Exception procedure which is treated
6883 -- specially, as is a call to Reraise_Occurrence.
6885 -- We suppress the warning in these cases since it is likely that
6886 -- the programmer really does not expect to deal with the case
6887 -- of Null_Occurrence, and thus would find a warning about a
6888 -- missing return curious, and raising Program_Error does not
6889 -- seem such a bad behavior if this does occur.
6891 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6892 -- behavior will be to raise Constraint_Error (see AI-329).
6894 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6896 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6898 Raise_Exception_Call := True;
6900 -- For Raise_Exception call, test first argument, if it is
6901 -- an attribute reference for a 'Identity call, then we know
6902 -- that the call cannot possibly return.
6905 Arg : constant Node_Id :=
6906 Original_Node (First_Actual (Last_Stm));
6908 if Nkind (Arg) = N_Attribute_Reference
6909 and then Attribute_Name (Arg) = Name_Identity
6916 -- If statement, need to look inside if there is an else and check
6917 -- each constituent statement sequence for proper termination.
6919 elsif Kind = N_If_Statement
6920 and then Present (Else_Statements (Last_Stm))
6922 Check_Statement_Sequence (Then_Statements (Last_Stm));
6923 Check_Statement_Sequence (Else_Statements (Last_Stm));
6925 if Present (Elsif_Parts (Last_Stm)) then
6927 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6930 while Present (Elsif_Part) loop
6931 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6939 -- Case statement, check each case for proper termination
6941 elsif Kind = N_Case_Statement then
6945 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6946 while Present (Case_Alt) loop
6947 Check_Statement_Sequence (Statements (Case_Alt));
6948 Next_Non_Pragma (Case_Alt);
6954 -- Block statement, check its handled sequence of statements
6956 elsif Kind = N_Block_Statement then
6962 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6971 -- Loop statement. If there is an iteration scheme, we can definitely
6972 -- fall out of the loop. Similarly if there is an exit statement, we
6973 -- can fall out. In either case we need a following return.
6975 elsif Kind = N_Loop_Statement then
6976 if Present (Iteration_Scheme (Last_Stm))
6977 or else Has_Exit (Entity (Identifier (Last_Stm)))
6981 -- A loop with no exit statement or iteration scheme is either
6982 -- an infinite loop, or it has some other exit (raise/return).
6983 -- In either case, no warning is required.
6989 -- Timed entry call, check entry call and delay alternatives
6991 -- Note: in expanded code, the timed entry call has been converted
6992 -- to a set of expanded statements on which the check will work
6993 -- correctly in any case.
6995 elsif Kind = N_Timed_Entry_Call then
6997 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6998 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
7001 -- If statement sequence of entry call alternative is missing,
7002 -- then we can definitely fall through, and we post the error
7003 -- message on the entry call alternative itself.
7005 if No (Statements (ECA)) then
7008 -- If statement sequence of delay alternative is missing, then
7009 -- we can definitely fall through, and we post the error
7010 -- message on the delay alternative itself.
7012 -- Note: if both ECA and DCA are missing the return, then we
7013 -- post only one message, should be enough to fix the bugs.
7014 -- If not we will get a message next time on the DCA when the
7017 elsif No (Statements (DCA)) then
7020 -- Else check both statement sequences
7023 Check_Statement_Sequence (Statements (ECA));
7024 Check_Statement_Sequence (Statements (DCA));
7029 -- Conditional entry call, check entry call and else part
7031 -- Note: in expanded code, the conditional entry call has been
7032 -- converted to a set of expanded statements on which the check
7033 -- will work correctly in any case.
7035 elsif Kind = N_Conditional_Entry_Call then
7037 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
7040 -- If statement sequence of entry call alternative is missing,
7041 -- then we can definitely fall through, and we post the error
7042 -- message on the entry call alternative itself.
7044 if No (Statements (ECA)) then
7047 -- Else check statement sequence and else part
7050 Check_Statement_Sequence (Statements (ECA));
7051 Check_Statement_Sequence (Else_Statements (Last_Stm));
7057 -- If we fall through, issue appropriate message
7061 -- Kill warning if last statement is a raise exception call,
7062 -- or a pragma Assert (False). Note that with assertions enabled,
7063 -- such a pragma has been converted into a raise exception call
7064 -- already, so the Assert_False is for the assertions off case.
7066 if not Raise_Exception_Call and then not Assert_False then
7068 -- In GNATprove mode, it is an error to have a missing return
7070 Error_Msg_Warn := SPARK_Mode /= On;
7072 -- Issue error message or warning
7075 ("RETURN statement missing following this statement<<!",
7078 ("\Program_Error ]<<!", Last_Stm);
7081 -- Note: we set Err even though we have not issued a warning
7082 -- because we still have a case of a missing return. This is
7083 -- an extremely marginal case, probably will never be noticed
7084 -- but we might as well get it right.
7088 -- Otherwise we have the case of a procedure marked No_Return
7091 if not Raise_Exception_Call then
7092 if GNATprove_Mode then
7094 ("implied return after this statement would have raised "
7095 & "Program_Error", Last_Stm);
7097 -- In normal compilation mode, do not warn on a generated call
7098 -- (e.g. in the body of a renaming as completion).
7100 elsif Comes_From_Source (Last_Stm) then
7102 ("implied return after this statement will raise "
7103 & "Program_Error??", Last_Stm);
7106 Error_Msg_Warn := SPARK_Mode /= On;
7108 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
7112 RE : constant Node_Id :=
7113 Make_Raise_Program_Error (Sloc (Last_Stm),
7114 Reason => PE_Implicit_Return);
7116 Insert_After (Last_Stm, RE);
7120 end Check_Statement_Sequence;
7122 -- Start of processing for Check_Returns
7126 Check_Statement_Sequence (Statements (HSS));
7128 if Present (Exception_Handlers (HSS)) then
7129 Handler := First_Non_Pragma (Exception_Handlers (HSS));
7130 while Present (Handler) loop
7131 Check_Statement_Sequence (Statements (Handler));
7132 Next_Non_Pragma (Handler);
7137 ----------------------------
7138 -- Check_Subprogram_Order --
7139 ----------------------------
7141 procedure Check_Subprogram_Order (N : Node_Id) is
7143 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
7144 -- This is used to check if S1 > S2 in the sense required by this test,
7145 -- for example nameab < namec, but name2 < name10.
7147 -----------------------------
7148 -- Subprogram_Name_Greater --
7149 -----------------------------
7151 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
7156 -- Deal with special case where names are identical except for a
7157 -- numerical suffix. These are handled specially, taking the numeric
7158 -- ordering from the suffix into account.
7161 while S1 (L1) in '0' .. '9' loop
7166 while S2 (L2) in '0' .. '9' loop
7170 -- If non-numeric parts non-equal, do straight compare
7172 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
7175 -- If non-numeric parts equal, compare suffixed numeric parts. Note
7176 -- that a missing suffix is treated as numeric zero in this test.
7180 while L1 < S1'Last loop
7182 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
7186 while L2 < S2'Last loop
7188 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
7193 end Subprogram_Name_Greater;
7195 -- Start of processing for Check_Subprogram_Order
7198 -- Check body in alpha order if this is option
7201 and then Style_Check_Order_Subprograms
7202 and then Nkind (N) = N_Subprogram_Body
7203 and then Comes_From_Source (N)
7204 and then In_Extended_Main_Source_Unit (N)
7208 renames Scope_Stack.Table
7209 (Scope_Stack.Last).Last_Subprogram_Name;
7211 Body_Id : constant Entity_Id :=
7212 Defining_Entity (Specification (N));
7215 Get_Decoded_Name_String (Chars (Body_Id));
7218 if Subprogram_Name_Greater
7219 (LSN.all, Name_Buffer (1 .. Name_Len))
7221 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7227 LSN := new String'(Name_Buffer (1 .. Name_Len));
7230 end Check_Subprogram_Order;
7232 ------------------------------
7233 -- Check_Subtype_Conformant --
7234 ------------------------------
7236 procedure Check_Subtype_Conformant
7237 (New_Id : Entity_Id;
7239 Err_Loc : Node_Id := Empty;
7240 Skip_Controlling_Formals : Boolean := False;
7241 Get_Inst : Boolean := False)
7244 pragma Warnings (Off, Result);
7247 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7248 Skip_Controlling_Formals => Skip_Controlling_Formals,
7249 Get_Inst => Get_Inst);
7250 end Check_Subtype_Conformant;
7252 -----------------------------------
7253 -- Check_Synchronized_Overriding --
7254 -----------------------------------
7256 procedure Check_Synchronized_Overriding
7257 (Def_Id : Entity_Id;
7258 Overridden_Subp : out Entity_Id)
7260 Ifaces_List : Elist_Id;
7264 function Is_Valid_Formal (F : Entity_Id) return Boolean;
7265 -- Predicate for legality rule in 9.4 (11.9/2): If an inherited
7266 -- subprogram is implemented by a protected procedure or entry,
7267 -- its first parameter must be out, in out, or access-to-variable.
7269 function Matches_Prefixed_View_Profile
7270 (Prim_Params : List_Id;
7271 Iface_Params : List_Id) return Boolean;
7272 -- Determine whether a subprogram's parameter profile Prim_Params
7273 -- matches that of a potentially overridden interface subprogram
7274 -- Iface_Params. Also determine if the type of first parameter of
7275 -- Iface_Params is an implemented interface.
7277 ----------------------
7278 -- Is_Valid_Formal --
7279 ----------------------
7281 function Is_Valid_Formal (F : Entity_Id) return Boolean is
7284 Ekind_In (F, E_In_Out_Parameter, E_Out_Parameter)
7286 (Nkind (Parameter_Type (Parent (F))) = N_Access_Definition
7287 and then not Constant_Present (Parameter_Type (Parent (F))));
7288 end Is_Valid_Formal;
7290 -----------------------------------
7291 -- Matches_Prefixed_View_Profile --
7292 -----------------------------------
7294 function Matches_Prefixed_View_Profile
7295 (Prim_Params : List_Id;
7296 Iface_Params : List_Id) return Boolean
7298 function Is_Implemented
7299 (Ifaces_List : Elist_Id;
7300 Iface : Entity_Id) return Boolean;
7301 -- Determine if Iface is implemented by the current task or
7304 --------------------
7305 -- Is_Implemented --
7306 --------------------
7308 function Is_Implemented
7309 (Ifaces_List : Elist_Id;
7310 Iface : Entity_Id) return Boolean
7312 Iface_Elmt : Elmt_Id;
7315 Iface_Elmt := First_Elmt (Ifaces_List);
7316 while Present (Iface_Elmt) loop
7317 if Node (Iface_Elmt) = Iface then
7321 Next_Elmt (Iface_Elmt);
7329 Iface_Id : Entity_Id;
7330 Iface_Param : Node_Id;
7331 Iface_Typ : Entity_Id;
7332 Prim_Id : Entity_Id;
7333 Prim_Param : Node_Id;
7334 Prim_Typ : Entity_Id;
7336 -- Start of processing for Matches_Prefixed_View_Profile
7339 Iface_Param := First (Iface_Params);
7340 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7342 if Is_Access_Type (Iface_Typ) then
7343 Iface_Typ := Designated_Type (Iface_Typ);
7346 Prim_Param := First (Prim_Params);
7348 -- The first parameter of the potentially overridden subprogram must
7349 -- be an interface implemented by Prim.
7351 if not Is_Interface (Iface_Typ)
7352 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7357 -- The checks on the object parameters are done, so move on to the
7358 -- rest of the parameters.
7360 if not In_Scope then
7361 Prim_Param := Next (Prim_Param);
7364 Iface_Param := Next (Iface_Param);
7365 while Present (Iface_Param) and then Present (Prim_Param) loop
7366 Iface_Id := Defining_Identifier (Iface_Param);
7367 Iface_Typ := Find_Parameter_Type (Iface_Param);
7369 Prim_Id := Defining_Identifier (Prim_Param);
7370 Prim_Typ := Find_Parameter_Type (Prim_Param);
7372 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7373 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7374 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7376 Iface_Typ := Designated_Type (Iface_Typ);
7377 Prim_Typ := Designated_Type (Prim_Typ);
7380 -- Case of multiple interface types inside a parameter profile
7382 -- (Obj_Param : in out Iface; ...; Param : Iface)
7384 -- If the interface type is implemented, then the matching type in
7385 -- the primitive should be the implementing record type.
7387 if Ekind (Iface_Typ) = E_Record_Type
7388 and then Is_Interface (Iface_Typ)
7389 and then Is_Implemented (Ifaces_List, Iface_Typ)
7391 if Prim_Typ /= Typ then
7395 -- The two parameters must be both mode and subtype conformant
7397 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7399 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7408 -- One of the two lists contains more parameters than the other
7410 if Present (Iface_Param) or else Present (Prim_Param) then
7415 end Matches_Prefixed_View_Profile;
7417 -- Start of processing for Check_Synchronized_Overriding
7420 Overridden_Subp := Empty;
7422 -- Def_Id must be an entry or a subprogram. We should skip predefined
7423 -- primitives internally generated by the front end; however at this
7424 -- stage predefined primitives are still not fully decorated. As a
7425 -- minor optimization we skip here internally generated subprograms.
7427 if (Ekind (Def_Id) /= E_Entry
7428 and then Ekind (Def_Id) /= E_Function
7429 and then Ekind (Def_Id) /= E_Procedure)
7430 or else not Comes_From_Source (Def_Id)
7435 -- Search for the concurrent declaration since it contains the list of
7436 -- all implemented interfaces. In this case, the subprogram is declared
7437 -- within the scope of a protected or a task type.
7439 if Present (Scope (Def_Id))
7440 and then Is_Concurrent_Type (Scope (Def_Id))
7441 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7443 Typ := Scope (Def_Id);
7446 -- The enclosing scope is not a synchronized type and the subprogram
7449 elsif No (First_Formal (Def_Id)) then
7452 -- The subprogram has formals and hence it may be a primitive of a
7456 Typ := Etype (First_Formal (Def_Id));
7458 if Is_Access_Type (Typ) then
7459 Typ := Directly_Designated_Type (Typ);
7462 if Is_Concurrent_Type (Typ)
7463 and then not Is_Generic_Actual_Type (Typ)
7467 -- This case occurs when the concurrent type is declared within a
7468 -- generic unit. As a result the corresponding record has been built
7469 -- and used as the type of the first formal, we just have to retrieve
7470 -- the corresponding concurrent type.
7472 elsif Is_Concurrent_Record_Type (Typ)
7473 and then not Is_Class_Wide_Type (Typ)
7474 and then Present (Corresponding_Concurrent_Type (Typ))
7476 Typ := Corresponding_Concurrent_Type (Typ);
7484 -- There is no overriding to check if this is an inherited operation in
7485 -- a type derivation for a generic actual.
7487 Collect_Interfaces (Typ, Ifaces_List);
7489 if Is_Empty_Elmt_List (Ifaces_List) then
7493 -- Determine whether entry or subprogram Def_Id overrides a primitive
7494 -- operation that belongs to one of the interfaces in Ifaces_List.
7497 Candidate : Entity_Id := Empty;
7498 Hom : Entity_Id := Empty;
7499 Subp : Entity_Id := Empty;
7502 -- Traverse the homonym chain, looking for a potentially overridden
7503 -- subprogram that belongs to an implemented interface.
7505 Hom := Current_Entity_In_Scope (Def_Id);
7506 while Present (Hom) loop
7510 or else not Is_Overloadable (Subp)
7511 or else not Is_Primitive (Subp)
7512 or else not Is_Dispatching_Operation (Subp)
7513 or else not Present (Find_Dispatching_Type (Subp))
7514 or else not Is_Interface (Find_Dispatching_Type (Subp))
7518 -- Entries and procedures can override abstract or null interface
7521 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7522 and then Ekind (Subp) = E_Procedure
7523 and then Matches_Prefixed_View_Profile
7524 (Parameter_Specifications (Parent (Def_Id)),
7525 Parameter_Specifications (Parent (Subp)))
7529 -- For an overridden subprogram Subp, check whether the mode
7530 -- of its first parameter is correct depending on the kind of
7531 -- synchronized type.
7534 Formal : constant Node_Id := First_Formal (Candidate);
7537 -- In order for an entry or a protected procedure to
7538 -- override, the first parameter of the overridden routine
7539 -- must be of mode "out", "in out", or access-to-variable.
7541 if Ekind_In (Candidate, E_Entry, E_Procedure)
7542 and then Is_Protected_Type (Typ)
7543 and then not Is_Valid_Formal (Formal)
7547 -- All other cases are OK since a task entry or routine does
7548 -- not have a restriction on the mode of the first parameter
7549 -- of the overridden interface routine.
7552 Overridden_Subp := Candidate;
7557 -- Functions can override abstract interface functions. Return
7558 -- types must be subtype conformant.
7560 elsif Ekind (Def_Id) = E_Function
7561 and then Ekind (Subp) = E_Function
7562 and then Matches_Prefixed_View_Profile
7563 (Parameter_Specifications (Parent (Def_Id)),
7564 Parameter_Specifications (Parent (Subp)))
7565 and then Conforming_Types
7566 (Etype (Def_Id), Etype (Subp), Subtype_Conformant)
7570 -- If an inherited subprogram is implemented by a protected
7571 -- function, then the first parameter of the inherited
7572 -- subprogram shall be of mode in, but not an access-to-
7573 -- variable parameter (RM 9.4(11/9)).
7575 if Present (First_Formal (Subp))
7576 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7578 (not Is_Access_Type (Etype (First_Formal (Subp)))
7580 Is_Access_Constant (Etype (First_Formal (Subp))))
7582 Overridden_Subp := Subp;
7587 Hom := Homonym (Hom);
7590 -- After examining all candidates for overriding, we are left with
7591 -- the best match, which is a mode-incompatible interface routine.
7593 if In_Scope and then Present (Candidate) then
7594 Error_Msg_PT (Def_Id, Candidate);
7597 Overridden_Subp := Candidate;
7600 end Check_Synchronized_Overriding;
7602 ---------------------------
7603 -- Check_Type_Conformant --
7604 ---------------------------
7606 procedure Check_Type_Conformant
7607 (New_Id : Entity_Id;
7609 Err_Loc : Node_Id := Empty)
7612 pragma Warnings (Off, Result);
7615 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7616 end Check_Type_Conformant;
7618 ---------------------------
7619 -- Can_Override_Operator --
7620 ---------------------------
7622 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7626 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7630 Typ := Base_Type (Etype (First_Formal (Subp)));
7632 -- Check explicitly that the operation is a primitive of the type
7634 return Operator_Matches_Spec (Subp, Subp)
7635 and then not Is_Generic_Type (Typ)
7636 and then Scope (Subp) = Scope (Typ)
7637 and then not Is_Class_Wide_Type (Typ);
7639 end Can_Override_Operator;
7641 ----------------------
7642 -- Conforming_Types --
7643 ----------------------
7645 function Conforming_Types
7648 Ctype : Conformance_Type;
7649 Get_Inst : Boolean := False) return Boolean
7651 function Base_Types_Match
7653 Typ_2 : Entity_Id) return Boolean;
7654 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7655 -- in different scopes (e.g. parent and child instances), then verify
7656 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7657 -- the same subtype chain. The whole purpose of this procedure is to
7658 -- prevent spurious ambiguities in an instantiation that may arise if
7659 -- two distinct generic types are instantiated with the same actual.
7661 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7662 -- An access parameter can designate an incomplete type. If the
7663 -- incomplete type is the limited view of a type from a limited_
7664 -- with_clause, check whether the non-limited view is available.
7665 -- If it is a (non-limited) incomplete type, get the full view.
7667 function Matches_Limited_With_View
7669 Typ_2 : Entity_Id) return Boolean;
7670 -- Returns True if and only if either Typ_1 denotes a limited view of
7671 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7672 -- the limited with view of a type is used in a subprogram declaration
7673 -- and the subprogram body is in the scope of a regular with clause for
7674 -- the same unit. In such a case, the two type entities are considered
7675 -- identical for purposes of conformance checking.
7677 ----------------------
7678 -- Base_Types_Match --
7679 ----------------------
7681 function Base_Types_Match
7683 Typ_2 : Entity_Id) return Boolean
7685 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7686 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7689 if Typ_1 = Typ_2 then
7692 elsif Base_1 = Base_2 then
7694 -- The following is too permissive. A more precise test should
7695 -- check that the generic actual is an ancestor subtype of the
7698 -- See code in Find_Corresponding_Spec that applies an additional
7699 -- filter to handle accidental amiguities in instances.
7702 not Is_Generic_Actual_Type (Typ_1)
7703 or else not Is_Generic_Actual_Type (Typ_2)
7704 or else Scope (Typ_1) /= Scope (Typ_2);
7706 -- If Typ_2 is a generic actual type it is declared as the subtype of
7707 -- the actual. If that actual is itself a subtype we need to use its
7708 -- own base type to check for compatibility.
7710 elsif Ekind (Base_2) = Ekind (Typ_2)
7711 and then Base_1 = Base_Type (Base_2)
7715 elsif Ekind (Base_1) = Ekind (Typ_1)
7716 and then Base_2 = Base_Type (Base_1)
7723 end Base_Types_Match;
7725 --------------------------
7726 -- Find_Designated_Type --
7727 --------------------------
7729 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7733 Desig := Directly_Designated_Type (Typ);
7735 if Ekind (Desig) = E_Incomplete_Type then
7737 -- If regular incomplete type, get full view if available
7739 if Present (Full_View (Desig)) then
7740 Desig := Full_View (Desig);
7742 -- If limited view of a type, get non-limited view if available,
7743 -- and check again for a regular incomplete type.
7745 elsif Present (Non_Limited_View (Desig)) then
7746 Desig := Get_Full_View (Non_Limited_View (Desig));
7751 end Find_Designated_Type;
7753 -------------------------------
7754 -- Matches_Limited_With_View --
7755 -------------------------------
7757 function Matches_Limited_With_View
7759 Typ_2 : Entity_Id) return Boolean
7761 function Is_Matching_Limited_View
7763 View : Entity_Id) return Boolean;
7764 -- Determine whether non-limited view View denotes type Typ in some
7765 -- conformant fashion.
7767 ------------------------------
7768 -- Is_Matching_Limited_View --
7769 ------------------------------
7771 function Is_Matching_Limited_View
7773 View : Entity_Id) return Boolean
7775 Root_Typ : Entity_Id;
7776 Root_View : Entity_Id;
7779 -- The non-limited view directly denotes the type
7784 -- The type is a subtype of the non-limited view
7786 elsif Is_Subtype_Of (Typ, View) then
7789 -- Both the non-limited view and the type denote class-wide types
7791 elsif Is_Class_Wide_Type (Typ)
7792 and then Is_Class_Wide_Type (View)
7794 Root_Typ := Root_Type (Typ);
7795 Root_View := Root_Type (View);
7797 if Root_Typ = Root_View then
7800 -- An incomplete tagged type and its full view may receive two
7801 -- distinct class-wide types when the related package has not
7802 -- been analyzed yet.
7805 -- type T is tagged; -- CW_1
7806 -- type T is tagged null record; -- CW_2
7809 -- This is because the package lacks any semantic information
7810 -- that may eventually link both views of T. As a consequence,
7811 -- a client of the limited view of Pack will see CW_2 while a
7812 -- client of the non-limited view of Pack will see CW_1.
7814 elsif Is_Incomplete_Type (Root_Typ)
7815 and then Present (Full_View (Root_Typ))
7816 and then Full_View (Root_Typ) = Root_View
7820 elsif Is_Incomplete_Type (Root_View)
7821 and then Present (Full_View (Root_View))
7822 and then Full_View (Root_View) = Root_Typ
7829 end Is_Matching_Limited_View;
7831 -- Start of processing for Matches_Limited_With_View
7834 -- In some cases a type imported through a limited_with clause, and
7835 -- its non-limited view are both visible, for example in an anonymous
7836 -- access-to-class-wide type in a formal, or when building the body
7837 -- for a subprogram renaming after the subprogram has been frozen.
7838 -- In these cases both entities designate the same type. In addition,
7839 -- if one of them is an actual in an instance, it may be a subtype of
7840 -- the non-limited view of the other.
7842 if From_Limited_With (Typ_1)
7843 and then From_Limited_With (Typ_2)
7844 and then Available_View (Typ_1) = Available_View (Typ_2)
7848 elsif From_Limited_With (Typ_1) then
7849 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7851 elsif From_Limited_With (Typ_2) then
7852 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7857 end Matches_Limited_With_View;
7861 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7863 Type_1 : Entity_Id := T1;
7864 Type_2 : Entity_Id := T2;
7866 -- Start of processing for Conforming_Types
7869 -- The context is an instance association for a formal access-to-
7870 -- subprogram type; the formal parameter types require mapping because
7871 -- they may denote other formal parameters of the generic unit.
7874 Type_1 := Get_Instance_Of (T1);
7875 Type_2 := Get_Instance_Of (T2);
7878 -- If one of the types is a view of the other introduced by a limited
7879 -- with clause, treat these as conforming for all purposes.
7881 if Matches_Limited_With_View (T1, T2) then
7884 elsif Base_Types_Match (Type_1, Type_2) then
7885 if Ctype <= Mode_Conformant then
7890 Subtypes_Statically_Match (Type_1, Type_2)
7891 and then Dimensions_Match (Type_1, Type_2);
7894 elsif Is_Incomplete_Or_Private_Type (Type_1)
7895 and then Present (Full_View (Type_1))
7896 and then Base_Types_Match (Full_View (Type_1), Type_2)
7899 Ctype <= Mode_Conformant
7900 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7902 elsif Ekind (Type_2) = E_Incomplete_Type
7903 and then Present (Full_View (Type_2))
7904 and then Base_Types_Match (Type_1, Full_View (Type_2))
7907 Ctype <= Mode_Conformant
7908 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7910 elsif Is_Private_Type (Type_2)
7911 and then In_Instance
7912 and then Present (Full_View (Type_2))
7913 and then Base_Types_Match (Type_1, Full_View (Type_2))
7916 Ctype <= Mode_Conformant
7917 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7919 -- Another confusion between views in a nested instance with an
7920 -- actual private type whose full view is not in scope.
7922 elsif Ekind (Type_2) = E_Private_Subtype
7923 and then In_Instance
7924 and then Etype (Type_2) = Type_1
7928 -- In Ada 2012, incomplete types (including limited views) can appear
7929 -- as actuals in instantiations, where they are conformant to the
7930 -- corresponding incomplete formal.
7932 elsif Is_Incomplete_Type (Type_1)
7933 and then Is_Incomplete_Type (Type_2)
7934 and then In_Instance
7935 and then (Used_As_Generic_Actual (Type_1)
7936 or else Used_As_Generic_Actual (Type_2))
7941 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7942 -- treated recursively because they carry a signature. As far as
7943 -- conformance is concerned, convention plays no role, and either
7944 -- or both could be access to protected subprograms.
7946 Are_Anonymous_Access_To_Subprogram_Types :=
7947 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7948 E_Anonymous_Access_Protected_Subprogram_Type)
7950 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7951 E_Anonymous_Access_Protected_Subprogram_Type);
7953 -- Test anonymous access type case. For this case, static subtype
7954 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7955 -- the base types because we may have built internal subtype entities
7956 -- to handle null-excluding types (see Process_Formals).
7958 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7960 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7962 -- Ada 2005 (AI-254)
7964 or else Are_Anonymous_Access_To_Subprogram_Types
7967 Desig_1 : Entity_Id;
7968 Desig_2 : Entity_Id;
7971 -- In Ada 2005, access constant indicators must match for
7972 -- subtype conformance.
7974 if Ada_Version >= Ada_2005
7975 and then Ctype >= Subtype_Conformant
7977 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7982 Desig_1 := Find_Designated_Type (Type_1);
7983 Desig_2 := Find_Designated_Type (Type_2);
7985 -- If the context is an instance association for a formal
7986 -- access-to-subprogram type; formal access parameter designated
7987 -- types require mapping because they may denote other formal
7988 -- parameters of the generic unit.
7991 Desig_1 := Get_Instance_Of (Desig_1);
7992 Desig_2 := Get_Instance_Of (Desig_2);
7995 -- It is possible for a Class_Wide_Type to be introduced for an
7996 -- incomplete type, in which case there is a separate class_ wide
7997 -- type for the full view. The types conform if their Etypes
7998 -- conform, i.e. one may be the full view of the other. This can
7999 -- only happen in the context of an access parameter, other uses
8000 -- of an incomplete Class_Wide_Type are illegal.
8002 if Is_Class_Wide_Type (Desig_1)
8004 Is_Class_Wide_Type (Desig_2)
8008 (Etype (Base_Type (Desig_1)),
8009 Etype (Base_Type (Desig_2)), Ctype);
8011 elsif Are_Anonymous_Access_To_Subprogram_Types then
8012 if Ada_Version < Ada_2005 then
8014 Ctype = Type_Conformant
8015 or else Subtypes_Statically_Match (Desig_1, Desig_2);
8017 -- We must check the conformance of the signatures themselves
8021 Conformant : Boolean;
8024 (Desig_1, Desig_2, Ctype, False, Conformant);
8029 -- A limited view of an actual matches the corresponding
8030 -- incomplete formal.
8032 elsif Ekind (Desig_2) = E_Incomplete_Subtype
8033 and then From_Limited_With (Desig_2)
8034 and then Used_As_Generic_Actual (Etype (Desig_2))
8039 return Base_Type (Desig_1) = Base_Type (Desig_2)
8040 and then (Ctype = Type_Conformant
8042 Subtypes_Statically_Match (Desig_1, Desig_2));
8046 -- Otherwise definitely no match
8049 if ((Ekind (Type_1) = E_Anonymous_Access_Type
8050 and then Is_Access_Type (Type_2))
8051 or else (Ekind (Type_2) = E_Anonymous_Access_Type
8052 and then Is_Access_Type (Type_1)))
8055 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
8057 May_Hide_Profile := True;
8062 end Conforming_Types;
8064 --------------------------
8065 -- Create_Extra_Formals --
8066 --------------------------
8068 procedure Create_Extra_Formals (E : Entity_Id) is
8069 First_Extra : Entity_Id := Empty;
8071 Last_Extra : Entity_Id := Empty;
8073 function Add_Extra_Formal
8074 (Assoc_Entity : Entity_Id;
8077 Suffix : String) return Entity_Id;
8078 -- Add an extra formal to the current list of formals and extra formals.
8079 -- The extra formal is added to the end of the list of extra formals,
8080 -- and also returned as the result. These formals are always of mode IN.
8081 -- The new formal has the type Typ, is declared in Scope, and its name
8082 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
8083 -- The following suffixes are currently used. They should not be changed
8084 -- without coordinating with CodePeer, which makes use of these to
8085 -- provide better messages.
8087 -- O denotes the Constrained bit.
8088 -- L denotes the accessibility level.
8089 -- BIP_xxx denotes an extra formal for a build-in-place function. See
8090 -- the full list in exp_ch6.BIP_Formal_Kind.
8092 ----------------------
8093 -- Add_Extra_Formal --
8094 ----------------------
8096 function Add_Extra_Formal
8097 (Assoc_Entity : Entity_Id;
8100 Suffix : String) return Entity_Id
8102 EF : constant Entity_Id :=
8103 Make_Defining_Identifier (Sloc (Assoc_Entity),
8104 Chars => New_External_Name (Chars (Assoc_Entity),
8108 -- A little optimization. Never generate an extra formal for the
8109 -- _init operand of an initialization procedure, since it could
8112 if Chars (Formal) = Name_uInit then
8116 Set_Ekind (EF, E_In_Parameter);
8117 Set_Actual_Subtype (EF, Typ);
8118 Set_Etype (EF, Typ);
8119 Set_Scope (EF, Scope);
8120 Set_Mechanism (EF, Default_Mechanism);
8121 Set_Formal_Validity (EF);
8123 if No (First_Extra) then
8125 Set_Extra_Formals (Scope, EF);
8128 if Present (Last_Extra) then
8129 Set_Extra_Formal (Last_Extra, EF);
8135 end Add_Extra_Formal;
8139 Formal_Type : Entity_Id;
8140 P_Formal : Entity_Id := Empty;
8142 -- Start of processing for Create_Extra_Formals
8145 -- We never generate extra formals if expansion is not active because we
8146 -- don't need them unless we are generating code.
8148 if not Expander_Active then
8152 -- No need to generate extra formals in interface thunks whose target
8153 -- primitive has no extra formals.
8155 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
8159 -- If this is a derived subprogram then the subtypes of the parent
8160 -- subprogram's formal parameters will be used to determine the need
8161 -- for extra formals.
8163 if Is_Overloadable (E) and then Present (Alias (E)) then
8164 P_Formal := First_Formal (Alias (E));
8167 Formal := First_Formal (E);
8168 while Present (Formal) loop
8169 Last_Extra := Formal;
8170 Next_Formal (Formal);
8173 -- If Extra_Formals were already created, don't do it again. This
8174 -- situation may arise for subprogram types created as part of
8175 -- dispatching calls (see Expand_Dispatching_Call).
8177 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
8181 -- If the subprogram is a predefined dispatching subprogram then don't
8182 -- generate any extra constrained or accessibility level formals. In
8183 -- general we suppress these for internal subprograms (by not calling
8184 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
8185 -- generated stream attributes do get passed through because extra
8186 -- build-in-place formals are needed in some cases (limited 'Input).
8188 if Is_Predefined_Internal_Operation (E) then
8189 goto Test_For_Func_Result_Extras;
8192 Formal := First_Formal (E);
8193 while Present (Formal) loop
8195 -- Create extra formal for supporting the attribute 'Constrained.
8196 -- The case of a private type view without discriminants also
8197 -- requires the extra formal if the underlying type has defaulted
8200 if Ekind (Formal) /= E_In_Parameter then
8201 if Present (P_Formal) then
8202 Formal_Type := Etype (P_Formal);
8204 Formal_Type := Etype (Formal);
8207 -- Do not produce extra formals for Unchecked_Union parameters.
8208 -- Jump directly to the end of the loop.
8210 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
8211 goto Skip_Extra_Formal_Generation;
8214 if not Has_Discriminants (Formal_Type)
8215 and then Ekind (Formal_Type) in Private_Kind
8216 and then Present (Underlying_Type (Formal_Type))
8218 Formal_Type := Underlying_Type (Formal_Type);
8221 -- Suppress the extra formal if formal's subtype is constrained or
8222 -- indefinite, or we're compiling for Ada 2012 and the underlying
8223 -- type is tagged and limited. In Ada 2012, a limited tagged type
8224 -- can have defaulted discriminants, but 'Constrained is required
8225 -- to return True, so the formal is never needed (see AI05-0214).
8226 -- Note that this ensures consistency of calling sequences for
8227 -- dispatching operations when some types in a class have defaults
8228 -- on discriminants and others do not (and requiring the extra
8229 -- formal would introduce distributed overhead).
8231 -- If the type does not have a completion yet, treat as prior to
8232 -- Ada 2012 for consistency.
8234 if Has_Discriminants (Formal_Type)
8235 and then not Is_Constrained (Formal_Type)
8236 and then Is_Definite_Subtype (Formal_Type)
8237 and then (Ada_Version < Ada_2012
8238 or else No (Underlying_Type (Formal_Type))
8240 (Is_Limited_Type (Formal_Type)
8243 (Underlying_Type (Formal_Type)))))
8245 Set_Extra_Constrained
8246 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8250 -- Create extra formal for supporting accessibility checking. This
8251 -- is done for both anonymous access formals and formals of named
8252 -- access types that are marked as controlling formals. The latter
8253 -- case can occur when Expand_Dispatching_Call creates a subprogram
8254 -- type and substitutes the types of access-to-class-wide actuals
8255 -- for the anonymous access-to-specific-type of controlling formals.
8256 -- Base_Type is applied because in cases where there is a null
8257 -- exclusion the formal may have an access subtype.
8259 -- This is suppressed if we specifically suppress accessibility
8260 -- checks at the package level for either the subprogram, or the
8261 -- package in which it resides. However, we do not suppress it
8262 -- simply if the scope has accessibility checks suppressed, since
8263 -- this could cause trouble when clients are compiled with a
8264 -- different suppression setting. The explicit checks at the
8265 -- package level are safe from this point of view.
8267 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8268 or else (Is_Controlling_Formal (Formal)
8269 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8271 (Explicit_Suppress (E, Accessibility_Check)
8273 Explicit_Suppress (Scope (E), Accessibility_Check))
8276 or else Present (Extra_Accessibility (P_Formal)))
8278 Set_Extra_Accessibility
8279 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8282 -- This label is required when skipping extra formal generation for
8283 -- Unchecked_Union parameters.
8285 <<Skip_Extra_Formal_Generation>>
8287 if Present (P_Formal) then
8288 Next_Formal (P_Formal);
8291 Next_Formal (Formal);
8294 <<Test_For_Func_Result_Extras>>
8296 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8297 -- function call is ... determined by the point of call ...".
8299 if Needs_Result_Accessibility_Level (E) then
8300 Set_Extra_Accessibility_Of_Result
8301 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8304 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8305 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8307 if Is_Build_In_Place_Function (E) then
8309 Result_Subt : constant Entity_Id := Etype (E);
8310 Formal_Typ : Entity_Id;
8311 Subp_Decl : Node_Id;
8312 Discard : Entity_Id;
8315 -- In the case of functions with unconstrained result subtypes,
8316 -- add a 4-state formal indicating whether the return object is
8317 -- allocated by the caller (1), or should be allocated by the
8318 -- callee on the secondary stack (2), in the global heap (3), or
8319 -- in a user-defined storage pool (4). For the moment we just use
8320 -- Natural for the type of this formal. Note that this formal
8321 -- isn't usually needed in the case where the result subtype is
8322 -- constrained, but it is needed when the function has a tagged
8323 -- result, because generally such functions can be called in a
8324 -- dispatching context and such calls must be handled like calls
8325 -- to a class-wide function.
8327 if Needs_BIP_Alloc_Form (E) then
8330 (E, Standard_Natural,
8331 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8333 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8334 -- use a user-defined pool. This formal is not added on
8335 -- ZFP as those targets do not support pools.
8337 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8340 (E, RTE (RE_Root_Storage_Pool_Ptr),
8341 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8345 -- In the case of functions whose result type needs finalization,
8346 -- add an extra formal which represents the finalization master.
8348 if Needs_BIP_Finalization_Master (E) then
8351 (E, RTE (RE_Finalization_Master_Ptr),
8352 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8355 -- When the result type contains tasks, add two extra formals: the
8356 -- master of the tasks to be created, and the caller's activation
8359 if Needs_BIP_Task_Actuals (E) then
8362 (E, RTE (RE_Master_Id),
8363 E, BIP_Formal_Suffix (BIP_Task_Master));
8366 (E, RTE (RE_Activation_Chain_Access),
8367 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8370 -- All build-in-place functions get an extra formal that will be
8371 -- passed the address of the return object within the caller.
8374 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8376 -- Incomplete_View_From_Limited_With is needed here because
8377 -- gigi gets confused if the designated type is the full view
8378 -- coming from a limited-with'ed package. In the normal case,
8379 -- (no limited with) Incomplete_View_From_Limited_With
8380 -- returns Result_Subt.
8382 Set_Directly_Designated_Type
8383 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8384 Set_Etype (Formal_Typ, Formal_Typ);
8385 Set_Depends_On_Private
8386 (Formal_Typ, Has_Private_Component (Formal_Typ));
8387 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8388 Set_Is_Access_Constant (Formal_Typ, False);
8390 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8391 -- the designated type comes from the limited view (for back-end
8394 Set_From_Limited_With
8395 (Formal_Typ, From_Limited_With (Result_Subt));
8397 Layout_Type (Formal_Typ);
8399 -- Force the definition of the Itype in case of internal function
8400 -- calls within the same or nested scope.
8402 if Is_Subprogram_Or_Generic_Subprogram (E) then
8403 Subp_Decl := Parent (E);
8405 -- The insertion point for an Itype reference should be after
8406 -- the unit declaration node of the subprogram. An exception
8407 -- to this are inherited operations from a parent type in which
8408 -- case the derived type acts as their parent.
8410 if Nkind_In (Subp_Decl, N_Function_Specification,
8411 N_Procedure_Specification)
8413 Subp_Decl := Parent (Subp_Decl);
8416 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8421 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8425 -- If this is an instance of a generic, we need to have extra formals
8428 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8429 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8431 end Create_Extra_Formals;
8433 -----------------------------
8434 -- Enter_Overloaded_Entity --
8435 -----------------------------
8437 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8438 function Matches_Predefined_Op return Boolean;
8439 -- This returns an approximation of whether S matches a predefined
8440 -- operator, based on the operator symbol, and the parameter and result
8441 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8443 ---------------------------
8444 -- Matches_Predefined_Op --
8445 ---------------------------
8447 function Matches_Predefined_Op return Boolean is
8448 Formal_1 : constant Entity_Id := First_Formal (S);
8449 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8450 Op : constant Name_Id := Chars (S);
8451 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8452 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8457 if Present (Formal_2) then
8459 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8462 -- All but "&" and "**" have same-types parameters
8471 if Type_1 /= Type_2 then
8476 -- Check parameter and result types
8484 Is_Boolean_Type (Result_Type)
8485 and then Result_Type = Type_1;
8491 Is_Integer_Type (Result_Type)
8492 and then Result_Type = Type_1;
8500 Is_Numeric_Type (Result_Type)
8501 and then Result_Type = Type_1;
8507 Is_Boolean_Type (Result_Type)
8508 and then not Is_Limited_Type (Type_1);
8516 Is_Boolean_Type (Result_Type)
8517 and then (Is_Array_Type (Type_1)
8518 or else Is_Scalar_Type (Type_1));
8520 when Name_Op_Concat =>
8521 return Is_Array_Type (Result_Type);
8523 when Name_Op_Expon =>
8525 (Is_Integer_Type (Result_Type)
8526 or else Is_Floating_Point_Type (Result_Type))
8527 and then Result_Type = Type_1
8528 and then Type_2 = Standard_Integer;
8531 raise Program_Error;
8544 Is_Numeric_Type (Result_Type)
8545 and then Result_Type = Type_1;
8549 Is_Boolean_Type (Result_Type)
8550 and then Result_Type = Type_1;
8553 raise Program_Error;
8556 end Matches_Predefined_Op;
8560 E : Entity_Id := Current_Entity_In_Scope (S);
8561 C_E : Entity_Id := Current_Entity (S);
8563 -- Start of processing for Enter_Overloaded_Entity
8567 Set_Has_Homonym (E);
8568 Set_Has_Homonym (S);
8571 Set_Is_Immediately_Visible (S);
8572 Set_Scope (S, Current_Scope);
8574 -- Chain new entity if front of homonym in current scope, so that
8575 -- homonyms are contiguous.
8577 if Present (E) and then E /= C_E then
8578 while Homonym (C_E) /= E loop
8579 C_E := Homonym (C_E);
8582 Set_Homonym (C_E, S);
8586 Set_Current_Entity (S);
8591 if Is_Inherited_Operation (S) then
8592 Append_Inherited_Subprogram (S);
8594 Append_Entity (S, Current_Scope);
8597 Set_Public_Status (S);
8599 if Debug_Flag_E then
8600 Write_Str ("New overloaded entity chain: ");
8601 Write_Name (Chars (S));
8604 while Present (E) loop
8605 Write_Str (" "); Write_Int (Int (E));
8612 -- Generate warning for hiding
8615 and then Comes_From_Source (S)
8616 and then In_Extended_Main_Source_Unit (S)
8623 -- Warn unless genuine overloading. Do not emit warning on
8624 -- hiding predefined operators in Standard (these are either an
8625 -- (artifact of our implicit declarations, or simple noise) but
8626 -- keep warning on a operator defined on a local subtype, because
8627 -- of the real danger that different operators may be applied in
8628 -- various parts of the program.
8630 -- Note that if E and S have the same scope, there is never any
8631 -- hiding. Either the two conflict, and the program is illegal,
8632 -- or S is overriding an implicit inherited subprogram.
8634 if Scope (E) /= Scope (S)
8635 and then (not Is_Overloadable (E)
8636 or else Subtype_Conformant (E, S))
8637 and then (Is_Immediately_Visible (E)
8638 or else Is_Potentially_Use_Visible (S))
8640 if Scope (E) = Standard_Standard then
8641 if Nkind (S) = N_Defining_Operator_Symbol
8642 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8644 and then Matches_Predefined_Op
8647 ("declaration of & hides predefined operator?h?", S);
8650 -- E not immediately within Standard
8653 Error_Msg_Sloc := Sloc (E);
8654 Error_Msg_N ("declaration of & hides one #?h?", S);
8659 end Enter_Overloaded_Entity;
8661 -----------------------------
8662 -- Check_Untagged_Equality --
8663 -----------------------------
8665 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8666 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8667 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8671 -- This check applies only if we have a subprogram declaration with an
8672 -- untagged record type that is conformant to the predefined op.
8674 if Nkind (Decl) /= N_Subprogram_Declaration
8675 or else not Is_Record_Type (Typ)
8676 or else Is_Tagged_Type (Typ)
8677 or else Etype (Next_Formal (First_Formal (Eq_Op))) /= Typ
8682 -- In Ada 2012 case, we will output errors or warnings depending on
8683 -- the setting of debug flag -gnatd.E.
8685 if Ada_Version >= Ada_2012 then
8686 Error_Msg_Warn := Debug_Flag_Dot_EE;
8688 -- In earlier versions of Ada, nothing to do unless we are warning on
8689 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8692 if not Warn_On_Ada_2012_Compatibility then
8697 -- Cases where the type has already been frozen
8699 if Is_Frozen (Typ) then
8701 -- The check applies to a primitive operation, so check that type
8702 -- and equality operation are in the same scope.
8704 if Scope (Typ) /= Current_Scope then
8707 -- If the type is a generic actual (sub)type, the operation is not
8708 -- primitive either because the base type is declared elsewhere.
8710 elsif Is_Generic_Actual_Type (Typ) then
8713 -- Here we have a definite error of declaration after freezing
8716 if Ada_Version >= Ada_2012 then
8718 ("equality operator must be declared before type & is "
8719 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8721 -- In Ada 2012 mode with error turned to warning, output one
8722 -- more warning to warn that the equality operation may not
8723 -- compose. This is the consequence of ignoring the error.
8725 if Error_Msg_Warn then
8726 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8731 ("equality operator must be declared before type& is "
8732 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8735 -- If we are in the package body, we could just move the
8736 -- declaration to the package spec, so add a message saying that.
8738 if In_Package_Body (Scope (Typ)) then
8739 if Ada_Version >= Ada_2012 then
8741 ("\move declaration to package spec<<", Eq_Op);
8744 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8747 -- Otherwise try to find the freezing point for better message.
8750 Obj_Decl := Next (Parent (Typ));
8751 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8752 if Nkind (Obj_Decl) = N_Object_Declaration
8753 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8755 -- Freezing point, output warnings
8757 if Ada_Version >= Ada_2012 then
8759 ("type& is frozen by declaration??", Obj_Decl, Typ);
8761 ("\an equality operator cannot be declared after "
8766 ("type& is frozen by declaration (Ada 2012)?y?",
8769 ("\an equality operator cannot be declared after "
8770 & "this point (Ada 2012)?y?",
8776 -- If we reach generated code for subprogram declaration
8777 -- or body, it is the body that froze the type and the
8778 -- declaration is legal.
8780 elsif Sloc (Obj_Decl) = Sloc (Decl) then
8789 -- Here if type is not frozen yet. It is illegal to have a primitive
8790 -- equality declared in the private part if the type is visible.
8792 elsif not In_Same_List (Parent (Typ), Decl)
8793 and then not Is_Limited_Type (Typ)
8795 -- Shouldn't we give an RM reference here???
8797 if Ada_Version >= Ada_2012 then
8799 ("equality operator appears too late<<", Eq_Op);
8802 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8805 -- No error detected
8810 end Check_Untagged_Equality;
8812 -----------------------------
8813 -- Find_Corresponding_Spec --
8814 -----------------------------
8816 function Find_Corresponding_Spec
8818 Post_Error : Boolean := True) return Entity_Id
8820 Spec : constant Node_Id := Specification (N);
8821 Designator : constant Entity_Id := Defining_Entity (Spec);
8825 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8826 -- Even if fully conformant, a body may depend on a generic actual when
8827 -- the spec does not, or vice versa, in which case they were distinct
8828 -- entities in the generic.
8830 -------------------------------
8831 -- Different_Generic_Profile --
8832 -------------------------------
8834 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8837 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8838 -- Check that the types of corresponding formals have the same
8839 -- generic actual if any. We have to account for subtypes of a
8840 -- generic formal, declared between a spec and a body, which may
8841 -- appear distinct in an instance but matched in the generic, and
8842 -- the subtype may be used either in the spec or the body of the
8843 -- subprogram being checked.
8845 -------------------------
8846 -- Same_Generic_Actual --
8847 -------------------------
8849 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8851 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8852 -- Predicate to check whether S1 is a subtype of S2 in the source
8855 -------------------------
8856 -- Is_Declared_Subtype --
8857 -------------------------
8859 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8861 return Comes_From_Source (Parent (S1))
8862 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8863 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8864 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8865 end Is_Declared_Subtype;
8867 -- Start of processing for Same_Generic_Actual
8870 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8871 or else Is_Declared_Subtype (T1, T2)
8872 or else Is_Declared_Subtype (T2, T1);
8873 end Same_Generic_Actual;
8875 -- Start of processing for Different_Generic_Profile
8878 if not In_Instance then
8881 elsif Ekind (E) = E_Function
8882 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8887 F1 := First_Formal (Designator);
8888 F2 := First_Formal (E);
8889 while Present (F1) loop
8890 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8899 end Different_Generic_Profile;
8901 -- Start of processing for Find_Corresponding_Spec
8904 E := Current_Entity (Designator);
8905 while Present (E) loop
8907 -- We are looking for a matching spec. It must have the same scope,
8908 -- and the same name, and either be type conformant, or be the case
8909 -- of a library procedure spec and its body (which belong to one
8910 -- another regardless of whether they are type conformant or not).
8912 if Scope (E) = Current_Scope then
8913 if Current_Scope = Standard_Standard
8914 or else (Ekind (E) = Ekind (Designator)
8915 and then Type_Conformant (E, Designator))
8917 -- Within an instantiation, we know that spec and body are
8918 -- subtype conformant, because they were subtype conformant in
8919 -- the generic. We choose the subtype-conformant entity here as
8920 -- well, to resolve spurious ambiguities in the instance that
8921 -- were not present in the generic (i.e. when two different
8922 -- types are given the same actual). If we are looking for a
8923 -- spec to match a body, full conformance is expected.
8927 -- Inherit the convention and "ghostness" of the matching
8928 -- spec to ensure proper full and subtype conformance.
8930 Set_Convention (Designator, Convention (E));
8932 -- Skip past subprogram bodies and subprogram renamings that
8933 -- may appear to have a matching spec, but that aren't fully
8934 -- conformant with it. That can occur in cases where an
8935 -- actual type causes unrelated homographs in the instance.
8937 if Nkind_In (N, N_Subprogram_Body,
8938 N_Subprogram_Renaming_Declaration)
8939 and then Present (Homonym (E))
8940 and then not Fully_Conformant (Designator, E)
8944 elsif not Subtype_Conformant (Designator, E) then
8947 elsif Different_Generic_Profile (E) then
8952 -- Ada 2012 (AI05-0165): For internally generated bodies of
8953 -- null procedures locate the internally generated spec. We
8954 -- enforce mode conformance since a tagged type may inherit
8955 -- from interfaces several null primitives which differ only
8956 -- in the mode of the formals.
8958 if not (Comes_From_Source (E))
8959 and then Is_Null_Procedure (E)
8960 and then not Mode_Conformant (Designator, E)
8964 -- For null procedures coming from source that are completions,
8965 -- analysis of the generated body will establish the link.
8967 elsif Comes_From_Source (E)
8968 and then Nkind (Spec) = N_Procedure_Specification
8969 and then Null_Present (Spec)
8973 -- Expression functions can be completions, but cannot be
8974 -- completed by an explicit body.
8976 elsif Comes_From_Source (E)
8977 and then Comes_From_Source (N)
8978 and then Nkind (N) = N_Subprogram_Body
8979 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8980 N_Expression_Function
8982 Error_Msg_Sloc := Sloc (E);
8983 Error_Msg_N ("body conflicts with expression function#", N);
8986 elsif not Has_Completion (E) then
8987 if Nkind (N) /= N_Subprogram_Body_Stub then
8988 Set_Corresponding_Spec (N, E);
8991 Set_Has_Completion (E);
8994 elsif Nkind (Parent (N)) = N_Subunit then
8996 -- If this is the proper body of a subunit, the completion
8997 -- flag is set when analyzing the stub.
9001 -- If E is an internal function with a controlling result that
9002 -- was created for an operation inherited by a null extension,
9003 -- it may be overridden by a body without a previous spec (one
9004 -- more reason why these should be shunned). In that case we
9005 -- remove the generated body if present, because the current
9006 -- one is the explicit overriding.
9008 elsif Ekind (E) = E_Function
9009 and then Ada_Version >= Ada_2005
9010 and then not Comes_From_Source (E)
9011 and then Has_Controlling_Result (E)
9012 and then Is_Null_Extension (Etype (E))
9013 and then Comes_From_Source (Spec)
9015 Set_Has_Completion (E, False);
9018 and then Nkind (Parent (E)) = N_Function_Specification
9021 (Unit_Declaration_Node
9022 (Corresponding_Body (Unit_Declaration_Node (E))));
9026 -- If expansion is disabled, or if the wrapper function has
9027 -- not been generated yet, this a late body overriding an
9028 -- inherited operation, or it is an overriding by some other
9029 -- declaration before the controlling result is frozen. In
9030 -- either case this is a declaration of a new entity.
9036 -- If the body already exists, then this is an error unless
9037 -- the previous declaration is the implicit declaration of a
9038 -- derived subprogram. It is also legal for an instance to
9039 -- contain type conformant overloadable declarations (but the
9040 -- generic declaration may not), per 8.3(26/2).
9042 elsif No (Alias (E))
9043 and then not Is_Intrinsic_Subprogram (E)
9044 and then not In_Instance
9047 Error_Msg_Sloc := Sloc (E);
9049 if Is_Imported (E) then
9051 ("body not allowed for imported subprogram & declared#",
9054 Error_Msg_NE ("duplicate body for & declared#", N, E);
9058 -- Child units cannot be overloaded, so a conformance mismatch
9059 -- between body and a previous spec is an error.
9061 elsif Is_Child_Unit (E)
9063 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
9065 Nkind (Parent (Unit_Declaration_Node (Designator))) =
9070 ("body of child unit does not match previous declaration", N);
9078 -- On exit, we know that no previous declaration of subprogram exists
9081 end Find_Corresponding_Spec;
9083 ----------------------
9084 -- Fully_Conformant --
9085 ----------------------
9087 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9090 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
9092 end Fully_Conformant;
9094 ----------------------------------
9095 -- Fully_Conformant_Expressions --
9096 ----------------------------------
9098 function Fully_Conformant_Expressions
9099 (Given_E1 : Node_Id;
9101 Report : Boolean := False) return Boolean
9103 E1 : constant Node_Id := Original_Node (Given_E1);
9104 E2 : constant Node_Id := Original_Node (Given_E2);
9105 -- We always test conformance on original nodes, since it is possible
9106 -- for analysis and/or expansion to make things look as though they
9107 -- conform when they do not, e.g. by converting 1+2 into 3.
9109 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean;
9112 function FCL (L1 : List_Id; L2 : List_Id) return Boolean;
9113 -- Compare elements of two lists for conformance. Elements have to be
9114 -- conformant, and actuals inserted as default parameters do not match
9115 -- explicit actuals with the same value.
9117 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean;
9118 -- Compare an operator node with a function call
9124 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean is
9126 return Fully_Conformant_Expressions (Given_E1, Given_E2, Report);
9133 function FCL (L1 : List_Id; L2 : List_Id) return Boolean is
9138 if L1 = No_List then
9144 if L2 = No_List then
9150 -- Compare two lists, skipping rewrite insertions (we want to compare
9151 -- the original trees, not the expanded versions).
9154 if Is_Rewrite_Insertion (N1) then
9156 elsif Is_Rewrite_Insertion (N2) then
9162 elsif not FCE (N1, N2) then
9175 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean is
9176 Actuals : constant List_Id := Parameter_Associations (Call_Node);
9181 or else Entity (Op_Node) /= Entity (Name (Call_Node))
9186 Act := First (Actuals);
9188 if Nkind (Op_Node) in N_Binary_Op then
9189 if not FCE (Left_Opnd (Op_Node), Act) then
9196 return Present (Act)
9197 and then FCE (Right_Opnd (Op_Node), Act)
9198 and then No (Next (Act));
9206 -- Start of processing for Fully_Conformant_Expressions
9211 -- Nonconformant if paren count does not match. Note: if some idiot
9212 -- complains that we don't do this right for more than 3 levels of
9213 -- parentheses, they will be treated with the respect they deserve.
9215 if Paren_Count (E1) /= Paren_Count (E2) then
9218 -- If same entities are referenced, then they are conformant even if
9219 -- they have different forms (RM 8.3.1(19-20)).
9221 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
9222 if Present (Entity (E1)) then
9223 Result := Entity (E1) = Entity (E2)
9225 -- One may be a discriminant that has been replaced by the
9226 -- corresponding discriminal.
9229 (Chars (Entity (E1)) = Chars (Entity (E2))
9230 and then Ekind (Entity (E1)) = E_Discriminant
9231 and then Ekind (Entity (E2)) = E_In_Parameter)
9233 -- The discriminant of a protected type is transformed into
9234 -- a local constant and then into a parameter of a protected
9238 (Ekind (Entity (E1)) = E_Constant
9239 and then Ekind (Entity (E2)) = E_In_Parameter
9240 and then Present (Discriminal_Link (Entity (E1)))
9241 and then Discriminal_Link (Entity (E1)) =
9242 Discriminal_Link (Entity (E2)))
9244 -- AI12-050: The loop variables of quantified expressions match
9245 -- if they have the same identifier, even though they may have
9246 -- different entities.
9249 (Chars (Entity (E1)) = Chars (Entity (E2))
9250 and then Ekind (Entity (E1)) = E_Loop_Parameter
9251 and then Ekind (Entity (E2)) = E_Loop_Parameter)
9253 -- A call to an instantiation of Unchecked_Conversion is
9254 -- rewritten with the name of the generated function created for
9255 -- the instance, and this must be special-cased.
9258 (Ekind (Entity (E1)) = E_Function
9259 and then Is_Intrinsic_Subprogram (Entity (E1))
9260 and then Is_Generic_Instance (Entity (E1))
9261 and then Entity (E2) = Alias (Entity (E1)));
9262 if Report and not Result then
9264 Text_Ptr'Max (Sloc (Entity (E1)), Sloc (Entity (E2)));
9266 ("Meaning of& differs because of declaration#", E1, E2);
9271 elsif Nkind (E1) = N_Expanded_Name
9272 and then Nkind (E2) = N_Expanded_Name
9273 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9274 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9276 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9279 -- Identifiers in component associations don't always have
9280 -- entities, but their names must conform.
9282 return Nkind (E1) = N_Identifier
9283 and then Nkind (E2) = N_Identifier
9284 and then Chars (E1) = Chars (E2);
9287 elsif Nkind (E1) = N_Character_Literal
9288 and then Nkind (E2) = N_Expanded_Name
9290 return Nkind (Selector_Name (E2)) = N_Character_Literal
9291 and then Chars (E1) = Chars (Selector_Name (E2));
9293 elsif Nkind (E2) = N_Character_Literal
9294 and then Nkind (E1) = N_Expanded_Name
9296 return Nkind (Selector_Name (E1)) = N_Character_Literal
9297 and then Chars (E2) = Chars (Selector_Name (E1));
9299 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9300 return FCO (E1, E2);
9302 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9303 return FCO (E2, E1);
9305 -- Otherwise we must have the same syntactic entity
9307 elsif Nkind (E1) /= Nkind (E2) then
9310 -- At this point, we specialize by node type
9316 FCL (Expressions (E1), Expressions (E2))
9318 FCL (Component_Associations (E1),
9319 Component_Associations (E2));
9322 if Nkind (Expression (E1)) = N_Qualified_Expression
9324 Nkind (Expression (E2)) = N_Qualified_Expression
9326 return FCE (Expression (E1), Expression (E2));
9328 -- Check that the subtype marks and any constraints
9333 Indic1 : constant Node_Id := Expression (E1);
9334 Indic2 : constant Node_Id := Expression (E2);
9339 if Nkind (Indic1) /= N_Subtype_Indication then
9341 Nkind (Indic2) /= N_Subtype_Indication
9342 and then Entity (Indic1) = Entity (Indic2);
9344 elsif Nkind (Indic2) /= N_Subtype_Indication then
9346 Nkind (Indic1) /= N_Subtype_Indication
9347 and then Entity (Indic1) = Entity (Indic2);
9350 if Entity (Subtype_Mark (Indic1)) /=
9351 Entity (Subtype_Mark (Indic2))
9356 Elt1 := First (Constraints (Constraint (Indic1)));
9357 Elt2 := First (Constraints (Constraint (Indic2)));
9358 while Present (Elt1) and then Present (Elt2) loop
9359 if not FCE (Elt1, Elt2) then
9372 when N_Attribute_Reference =>
9374 Attribute_Name (E1) = Attribute_Name (E2)
9375 and then FCL (Expressions (E1), Expressions (E2));
9379 Entity (E1) = Entity (E2)
9380 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9381 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9383 when N_Membership_Test
9387 FCE (Left_Opnd (E1), Left_Opnd (E2))
9389 FCE (Right_Opnd (E1), Right_Opnd (E2));
9391 when N_Case_Expression =>
9397 if not FCE (Expression (E1), Expression (E2)) then
9401 Alt1 := First (Alternatives (E1));
9402 Alt2 := First (Alternatives (E2));
9404 if Present (Alt1) /= Present (Alt2) then
9406 elsif No (Alt1) then
9410 if not FCE (Expression (Alt1), Expression (Alt2))
9411 or else not FCL (Discrete_Choices (Alt1),
9412 Discrete_Choices (Alt2))
9423 when N_Character_Literal =>
9425 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9427 when N_Component_Association =>
9429 FCL (Choices (E1), Choices (E2))
9431 FCE (Expression (E1), Expression (E2));
9433 when N_Explicit_Dereference =>
9435 FCE (Prefix (E1), Prefix (E2));
9437 when N_Extension_Aggregate =>
9439 FCL (Expressions (E1), Expressions (E2))
9440 and then Null_Record_Present (E1) =
9441 Null_Record_Present (E2)
9442 and then FCL (Component_Associations (E1),
9443 Component_Associations (E2));
9445 when N_Function_Call =>
9447 FCE (Name (E1), Name (E2))
9449 FCL (Parameter_Associations (E1),
9450 Parameter_Associations (E2));
9452 when N_If_Expression =>
9454 FCL (Expressions (E1), Expressions (E2));
9456 when N_Indexed_Component =>
9458 FCE (Prefix (E1), Prefix (E2))
9460 FCL (Expressions (E1), Expressions (E2));
9462 when N_Integer_Literal =>
9463 return (Intval (E1) = Intval (E2));
9468 when N_Operator_Symbol =>
9470 Chars (E1) = Chars (E2);
9472 when N_Others_Choice =>
9475 when N_Parameter_Association =>
9477 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9478 and then FCE (Explicit_Actual_Parameter (E1),
9479 Explicit_Actual_Parameter (E2));
9481 when N_Qualified_Expression
9483 | N_Unchecked_Type_Conversion
9486 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9488 FCE (Expression (E1), Expression (E2));
9490 when N_Quantified_Expression =>
9491 if not FCE (Condition (E1), Condition (E2)) then
9495 if Present (Loop_Parameter_Specification (E1))
9496 and then Present (Loop_Parameter_Specification (E2))
9499 L1 : constant Node_Id :=
9500 Loop_Parameter_Specification (E1);
9501 L2 : constant Node_Id :=
9502 Loop_Parameter_Specification (E2);
9506 Reverse_Present (L1) = Reverse_Present (L2)
9508 FCE (Defining_Identifier (L1),
9509 Defining_Identifier (L2))
9511 FCE (Discrete_Subtype_Definition (L1),
9512 Discrete_Subtype_Definition (L2));
9515 elsif Present (Iterator_Specification (E1))
9516 and then Present (Iterator_Specification (E2))
9519 I1 : constant Node_Id := Iterator_Specification (E1);
9520 I2 : constant Node_Id := Iterator_Specification (E2);
9524 FCE (Defining_Identifier (I1),
9525 Defining_Identifier (I2))
9527 Of_Present (I1) = Of_Present (I2)
9529 Reverse_Present (I1) = Reverse_Present (I2)
9530 and then FCE (Name (I1), Name (I2))
9531 and then FCE (Subtype_Indication (I1),
9532 Subtype_Indication (I2));
9535 -- The quantified expressions used different specifications to
9536 -- walk their respective ranges.
9544 FCE (Low_Bound (E1), Low_Bound (E2))
9546 FCE (High_Bound (E1), High_Bound (E2));
9548 when N_Real_Literal =>
9549 return (Realval (E1) = Realval (E2));
9551 when N_Selected_Component =>
9553 FCE (Prefix (E1), Prefix (E2))
9555 FCE (Selector_Name (E1), Selector_Name (E2));
9559 FCE (Prefix (E1), Prefix (E2))
9561 FCE (Discrete_Range (E1), Discrete_Range (E2));
9563 when N_String_Literal =>
9565 S1 : constant String_Id := Strval (E1);
9566 S2 : constant String_Id := Strval (E2);
9567 L1 : constant Nat := String_Length (S1);
9568 L2 : constant Nat := String_Length (S2);
9575 for J in 1 .. L1 loop
9576 if Get_String_Char (S1, J) /=
9577 Get_String_Char (S2, J)
9589 Entity (E1) = Entity (E2)
9591 FCE (Right_Opnd (E1), Right_Opnd (E2));
9593 -- All other node types cannot appear in this context. Strictly
9594 -- we should raise a fatal internal error. Instead we just ignore
9595 -- the nodes. This means that if anyone makes a mistake in the
9596 -- expander and mucks an expression tree irretrievably, the result
9597 -- will be a failure to detect a (probably very obscure) case
9598 -- of non-conformance, which is better than bombing on some
9599 -- case where two expressions do in fact conform.
9605 end Fully_Conformant_Expressions;
9607 ----------------------------------------
9608 -- Fully_Conformant_Discrete_Subtypes --
9609 ----------------------------------------
9611 function Fully_Conformant_Discrete_Subtypes
9612 (Given_S1 : Node_Id;
9613 Given_S2 : Node_Id) return Boolean
9615 S1 : constant Node_Id := Original_Node (Given_S1);
9616 S2 : constant Node_Id := Original_Node (Given_S2);
9618 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9619 -- Special-case for a bound given by a discriminant, which in the body
9620 -- is replaced with the discriminal of the enclosing type.
9622 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9623 -- Check both bounds
9625 -----------------------
9626 -- Conforming_Bounds --
9627 -----------------------
9629 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9631 if Is_Entity_Name (B1)
9632 and then Is_Entity_Name (B2)
9633 and then Ekind (Entity (B1)) = E_Discriminant
9635 return Chars (B1) = Chars (B2);
9638 return Fully_Conformant_Expressions (B1, B2);
9640 end Conforming_Bounds;
9642 -----------------------
9643 -- Conforming_Ranges --
9644 -----------------------
9646 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9649 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9651 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9652 end Conforming_Ranges;
9654 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9657 if Nkind (S1) /= Nkind (S2) then
9660 elsif Is_Entity_Name (S1) then
9661 return Entity (S1) = Entity (S2);
9663 elsif Nkind (S1) = N_Range then
9664 return Conforming_Ranges (S1, S2);
9666 elsif Nkind (S1) = N_Subtype_Indication then
9668 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9671 (Range_Expression (Constraint (S1)),
9672 Range_Expression (Constraint (S2)));
9676 end Fully_Conformant_Discrete_Subtypes;
9678 --------------------
9679 -- Install_Entity --
9680 --------------------
9682 procedure Install_Entity (E : Entity_Id) is
9683 Prev : constant Entity_Id := Current_Entity (E);
9685 Set_Is_Immediately_Visible (E);
9686 Set_Current_Entity (E);
9687 Set_Homonym (E, Prev);
9690 ---------------------
9691 -- Install_Formals --
9692 ---------------------
9694 procedure Install_Formals (Id : Entity_Id) is
9697 F := First_Formal (Id);
9698 while Present (F) loop
9702 end Install_Formals;
9704 -----------------------------
9705 -- Is_Interface_Conformant --
9706 -----------------------------
9708 function Is_Interface_Conformant
9709 (Tagged_Type : Entity_Id;
9710 Iface_Prim : Entity_Id;
9711 Prim : Entity_Id) return Boolean
9713 -- The operation may in fact be an inherited (implicit) operation
9714 -- rather than the original interface primitive, so retrieve the
9715 -- ultimate ancestor.
9717 Iface : constant Entity_Id :=
9718 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9719 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9721 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9722 -- Return the controlling formal of Prim
9724 ------------------------
9725 -- Controlling_Formal --
9726 ------------------------
9728 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9732 E := First_Entity (Prim);
9733 while Present (E) loop
9734 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9742 end Controlling_Formal;
9746 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9747 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9749 -- Start of processing for Is_Interface_Conformant
9752 pragma Assert (Is_Subprogram (Iface_Prim)
9753 and then Is_Subprogram (Prim)
9754 and then Is_Dispatching_Operation (Iface_Prim)
9755 and then Is_Dispatching_Operation (Prim));
9757 pragma Assert (Is_Interface (Iface)
9758 or else (Present (Alias (Iface_Prim))
9761 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9763 if Prim = Iface_Prim
9764 or else not Is_Subprogram (Prim)
9765 or else Ekind (Prim) /= Ekind (Iface_Prim)
9766 or else not Is_Dispatching_Operation (Prim)
9767 or else Scope (Prim) /= Scope (Tagged_Type)
9769 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9770 or else not Primitive_Names_Match (Iface_Prim, Prim)
9774 -- The mode of the controlling formals must match
9776 elsif Present (Iface_Ctrl_F)
9777 and then Present (Prim_Ctrl_F)
9778 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9782 -- Case of a procedure, or a function whose result type matches the
9783 -- result type of the interface primitive, or a function that has no
9784 -- controlling result (I or access I).
9786 elsif Ekind (Iface_Prim) = E_Procedure
9787 or else Etype (Prim) = Etype (Iface_Prim)
9788 or else not Has_Controlling_Result (Prim)
9790 return Type_Conformant
9791 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9793 -- Case of a function returning an interface, or an access to one. Check
9794 -- that the return types correspond.
9796 elsif Implements_Interface (Typ, Iface) then
9797 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9799 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9804 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9805 Skip_Controlling_Formals => True);
9811 end Is_Interface_Conformant;
9813 ---------------------------------
9814 -- Is_Non_Overriding_Operation --
9815 ---------------------------------
9817 function Is_Non_Overriding_Operation
9818 (Prev_E : Entity_Id;
9819 New_E : Entity_Id) return Boolean
9823 G_Typ : Entity_Id := Empty;
9825 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9826 -- If F_Type is a derived type associated with a generic actual subtype,
9827 -- then return its Generic_Parent_Type attribute, else return Empty.
9829 function Types_Correspond
9830 (P_Type : Entity_Id;
9831 N_Type : Entity_Id) return Boolean;
9832 -- Returns true if and only if the types (or designated types in the
9833 -- case of anonymous access types) are the same or N_Type is derived
9834 -- directly or indirectly from P_Type.
9836 -----------------------------
9837 -- Get_Generic_Parent_Type --
9838 -----------------------------
9840 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9846 if Is_Derived_Type (F_Typ)
9847 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9849 -- The tree must be traversed to determine the parent subtype in
9850 -- the generic unit, which unfortunately isn't always available
9851 -- via semantic attributes. ??? (Note: The use of Original_Node
9852 -- is needed for cases where a full derived type has been
9855 -- If the parent type is a scalar type, the derivation creates
9856 -- an anonymous base type for it, and the source type is its
9859 if Is_Scalar_Type (F_Typ)
9860 and then not Comes_From_Source (F_Typ)
9864 (Original_Node (Parent (First_Subtype (F_Typ))));
9866 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9868 if Nkind (Defn) = N_Derived_Type_Definition then
9869 Indic := Subtype_Indication (Defn);
9871 if Nkind (Indic) = N_Subtype_Indication then
9872 G_Typ := Entity (Subtype_Mark (Indic));
9874 G_Typ := Entity (Indic);
9877 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9878 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9880 return Generic_Parent_Type (Parent (G_Typ));
9886 end Get_Generic_Parent_Type;
9888 ----------------------
9889 -- Types_Correspond --
9890 ----------------------
9892 function Types_Correspond
9893 (P_Type : Entity_Id;
9894 N_Type : Entity_Id) return Boolean
9896 Prev_Type : Entity_Id := Base_Type (P_Type);
9897 New_Type : Entity_Id := Base_Type (N_Type);
9900 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9901 Prev_Type := Designated_Type (Prev_Type);
9904 if Ekind (New_Type) = E_Anonymous_Access_Type then
9905 New_Type := Designated_Type (New_Type);
9908 if Prev_Type = New_Type then
9911 elsif not Is_Class_Wide_Type (New_Type) then
9912 while Etype (New_Type) /= New_Type loop
9913 New_Type := Etype (New_Type);
9915 if New_Type = Prev_Type then
9921 end Types_Correspond;
9923 -- Start of processing for Is_Non_Overriding_Operation
9926 -- In the case where both operations are implicit derived subprograms
9927 -- then neither overrides the other. This can only occur in certain
9928 -- obscure cases (e.g., derivation from homographs created in a generic
9931 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9934 elsif Ekind (Current_Scope) = E_Package
9935 and then Is_Generic_Instance (Current_Scope)
9936 and then In_Private_Part (Current_Scope)
9937 and then Comes_From_Source (New_E)
9939 -- We examine the formals and result type of the inherited operation,
9940 -- to determine whether their type is derived from (the instance of)
9941 -- a generic type. The first such formal or result type is the one
9944 Formal := First_Formal (Prev_E);
9946 while Present (Formal) loop
9947 F_Typ := Base_Type (Etype (Formal));
9949 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9950 F_Typ := Designated_Type (F_Typ);
9953 G_Typ := Get_Generic_Parent_Type (F_Typ);
9954 exit when Present (G_Typ);
9956 Next_Formal (Formal);
9959 -- If the function dispatches on result check the result type
9961 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9962 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9969 -- If the generic type is a private type, then the original operation
9970 -- was not overriding in the generic, because there was no primitive
9971 -- operation to override.
9973 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9974 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9975 N_Formal_Private_Type_Definition
9979 -- The generic parent type is the ancestor of a formal derived
9980 -- type declaration. We need to check whether it has a primitive
9981 -- operation that should be overridden by New_E in the generic.
9985 P_Formal : Entity_Id;
9986 N_Formal : Entity_Id;
9990 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9993 while Present (Prim_Elt) loop
9994 P_Prim := Node (Prim_Elt);
9996 if Chars (P_Prim) = Chars (New_E)
9997 and then Ekind (P_Prim) = Ekind (New_E)
9999 P_Formal := First_Formal (P_Prim);
10000 N_Formal := First_Formal (New_E);
10001 while Present (P_Formal) and then Present (N_Formal) loop
10002 P_Typ := Etype (P_Formal);
10003 N_Typ := Etype (N_Formal);
10005 if not Types_Correspond (P_Typ, N_Typ) then
10009 Next_Entity (P_Formal);
10010 Next_Entity (N_Formal);
10013 -- Found a matching primitive operation belonging to the
10014 -- formal ancestor type, so the new subprogram is
10018 and then No (N_Formal)
10019 and then (Ekind (New_E) /= E_Function
10022 (Etype (P_Prim), Etype (New_E)))
10028 Next_Elmt (Prim_Elt);
10031 -- If no match found, then the new subprogram does not override
10032 -- in the generic (nor in the instance).
10034 -- If the type in question is not abstract, and the subprogram
10035 -- is, this will be an error if the new operation is in the
10036 -- private part of the instance. Emit a warning now, which will
10037 -- make the subsequent error message easier to understand.
10039 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
10040 and then Is_Abstract_Subprogram (Prev_E)
10041 and then In_Private_Part (Current_Scope)
10043 Error_Msg_Node_2 := F_Typ;
10045 ("private operation& in generic unit does not override "
10046 & "any primitive operation of& (RM 12.3 (18))??",
10056 end Is_Non_Overriding_Operation;
10058 -------------------------------------
10059 -- List_Inherited_Pre_Post_Aspects --
10060 -------------------------------------
10062 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
10064 if Opt.List_Inherited_Aspects
10065 and then Is_Subprogram_Or_Generic_Subprogram (E)
10068 Subps : constant Subprogram_List := Inherited_Subprograms (E);
10073 for Index in Subps'Range loop
10074 Items := Contract (Subps (Index));
10076 if Present (Items) then
10077 Prag := Pre_Post_Conditions (Items);
10078 while Present (Prag) loop
10079 Error_Msg_Sloc := Sloc (Prag);
10081 if Class_Present (Prag)
10082 and then not Split_PPC (Prag)
10084 if Pragma_Name (Prag) = Name_Precondition then
10086 ("info: & inherits `Pre''Class` aspect from "
10090 ("info: & inherits `Post''Class` aspect from "
10095 Prag := Next_Pragma (Prag);
10101 end List_Inherited_Pre_Post_Aspects;
10103 ------------------------------
10104 -- Make_Inequality_Operator --
10105 ------------------------------
10107 -- S is the defining identifier of an equality operator. We build a
10108 -- subprogram declaration with the right signature. This operation is
10109 -- intrinsic, because it is always expanded as the negation of the
10110 -- call to the equality function.
10112 procedure Make_Inequality_Operator (S : Entity_Id) is
10113 Loc : constant Source_Ptr := Sloc (S);
10116 Op_Name : Entity_Id;
10118 FF : constant Entity_Id := First_Formal (S);
10119 NF : constant Entity_Id := Next_Formal (FF);
10122 -- Check that equality was properly defined, ignore call if not
10129 A : constant Entity_Id :=
10130 Make_Defining_Identifier (Sloc (FF),
10131 Chars => Chars (FF));
10133 B : constant Entity_Id :=
10134 Make_Defining_Identifier (Sloc (NF),
10135 Chars => Chars (NF));
10138 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
10140 Formals := New_List (
10141 Make_Parameter_Specification (Loc,
10142 Defining_Identifier => A,
10144 New_Occurrence_Of (Etype (First_Formal (S)),
10145 Sloc (Etype (First_Formal (S))))),
10147 Make_Parameter_Specification (Loc,
10148 Defining_Identifier => B,
10150 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
10151 Sloc (Etype (Next_Formal (First_Formal (S)))))));
10154 Make_Subprogram_Declaration (Loc,
10156 Make_Function_Specification (Loc,
10157 Defining_Unit_Name => Op_Name,
10158 Parameter_Specifications => Formals,
10159 Result_Definition =>
10160 New_Occurrence_Of (Standard_Boolean, Loc)));
10162 -- Insert inequality right after equality if it is explicit or after
10163 -- the derived type when implicit. These entities are created only
10164 -- for visibility purposes, and eventually replaced in the course
10165 -- of expansion, so they do not need to be attached to the tree and
10166 -- seen by the back-end. Keeping them internal also avoids spurious
10167 -- freezing problems. The declaration is inserted in the tree for
10168 -- analysis, and removed afterwards. If the equality operator comes
10169 -- from an explicit declaration, attach the inequality immediately
10170 -- after. Else the equality is inherited from a derived type
10171 -- declaration, so insert inequality after that declaration.
10173 if No (Alias (S)) then
10174 Insert_After (Unit_Declaration_Node (S), Decl);
10175 elsif Is_List_Member (Parent (S)) then
10176 Insert_After (Parent (S), Decl);
10178 Insert_After (Parent (Etype (First_Formal (S))), Decl);
10181 Mark_Rewrite_Insertion (Decl);
10182 Set_Is_Intrinsic_Subprogram (Op_Name);
10185 Set_Has_Completion (Op_Name);
10186 Set_Corresponding_Equality (Op_Name, S);
10187 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
10189 end Make_Inequality_Operator;
10191 ----------------------
10192 -- May_Need_Actuals --
10193 ----------------------
10195 procedure May_Need_Actuals (Fun : Entity_Id) is
10200 F := First_Formal (Fun);
10202 while Present (F) loop
10203 if No (Default_Value (F)) then
10211 Set_Needs_No_Actuals (Fun, B);
10212 end May_Need_Actuals;
10214 ---------------------
10215 -- Mode_Conformant --
10216 ---------------------
10218 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
10221 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
10223 end Mode_Conformant;
10225 ---------------------------
10226 -- New_Overloaded_Entity --
10227 ---------------------------
10229 procedure New_Overloaded_Entity
10231 Derived_Type : Entity_Id := Empty)
10233 Overridden_Subp : Entity_Id := Empty;
10234 -- Set if the current scope has an operation that is type-conformant
10235 -- with S, and becomes hidden by S.
10237 Is_Primitive_Subp : Boolean;
10238 -- Set to True if the new subprogram is primitive
10241 -- Entity that S overrides
10243 procedure Check_For_Primitive_Subprogram
10244 (Is_Primitive : out Boolean;
10245 Is_Overriding : Boolean := False);
10246 -- If the subprogram being analyzed is a primitive operation of the type
10247 -- of a formal or result, set the Has_Primitive_Operations flag on the
10248 -- type, and set Is_Primitive to True (otherwise set to False). Set the
10249 -- corresponding flag on the entity itself for later use.
10251 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10252 -- True if a) E is a subprogram whose first formal is a concurrent type
10253 -- defined in the scope of E that has some entry or subprogram whose
10254 -- profile matches E, or b) E is an internally built dispatching
10255 -- subprogram of a protected type and there is a matching subprogram
10256 -- defined in the enclosing scope of the protected type, or c) E is
10257 -- an entry of a synchronized type and a matching procedure has been
10258 -- previously defined in the enclosing scope of the synchronized type.
10260 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10261 -- Check that E is declared in the private part of the current package,
10262 -- or in the package body, where it may hide a previous declaration.
10263 -- We can't use In_Private_Part by itself because this flag is also
10264 -- set when freezing entities, so we must examine the place of the
10265 -- declaration in the tree, and recognize wrapper packages as well.
10267 function Is_Overriding_Alias
10268 (Old_E : Entity_Id;
10269 New_E : Entity_Id) return Boolean;
10270 -- Check whether new subprogram and old subprogram are both inherited
10271 -- from subprograms that have distinct dispatch table entries. This can
10272 -- occur with derivations from instances with accidental homonyms. The
10273 -- function is conservative given that the converse is only true within
10274 -- instances that contain accidental overloadings.
10276 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10277 -- Report conflict between entities S and E
10279 ------------------------------------
10280 -- Check_For_Primitive_Subprogram --
10281 ------------------------------------
10283 procedure Check_For_Primitive_Subprogram
10284 (Is_Primitive : out Boolean;
10285 Is_Overriding : Boolean := False)
10287 Formal : Entity_Id;
10291 function Visible_Part_Type (T : Entity_Id) return Boolean;
10292 -- Returns true if T is declared in the visible part of the current
10293 -- package scope; otherwise returns false. Assumes that T is declared
10296 procedure Check_Private_Overriding (T : Entity_Id);
10297 -- Checks that if a primitive abstract subprogram of a visible
10298 -- abstract type is declared in a private part, then it must override
10299 -- an abstract subprogram declared in the visible part. Also checks
10300 -- that if a primitive function with a controlling result is declared
10301 -- in a private part, then it must override a function declared in
10302 -- the visible part.
10304 ------------------------------
10305 -- Check_Private_Overriding --
10306 ------------------------------
10308 procedure Check_Private_Overriding (T : Entity_Id) is
10309 function Overrides_Private_Part_Op return Boolean;
10310 -- This detects the special case where the overriding subprogram
10311 -- is overriding a subprogram that was declared in the same
10312 -- private part. That case is illegal by 3.9.3(10).
10314 function Overrides_Visible_Function
10315 (Partial_View : Entity_Id) return Boolean;
10316 -- True if S overrides a function in the visible part. The
10317 -- overridden function could be explicitly or implicitly declared.
10319 -------------------------------
10320 -- Overrides_Private_Part_Op --
10321 -------------------------------
10323 function Overrides_Private_Part_Op return Boolean is
10324 Over_Decl : constant Node_Id :=
10325 Unit_Declaration_Node (Overridden_Operation (S));
10326 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10329 pragma Assert (Is_Overriding);
10331 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10333 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10335 return In_Same_List (Over_Decl, Subp_Decl);
10336 end Overrides_Private_Part_Op;
10338 --------------------------------
10339 -- Overrides_Visible_Function --
10340 --------------------------------
10342 function Overrides_Visible_Function
10343 (Partial_View : Entity_Id) return Boolean
10346 if not Is_Overriding or else not Has_Homonym (S) then
10350 if not Present (Partial_View) then
10354 -- Search through all the homonyms H of S in the current
10355 -- package spec, and return True if we find one that matches.
10356 -- Note that Parent (H) will be the declaration of the
10357 -- partial view of T for a match.
10360 H : Entity_Id := S;
10364 exit when not Present (H) or else Scope (H) /= Scope (S);
10368 N_Private_Extension_Declaration,
10369 N_Private_Type_Declaration)
10370 and then Defining_Identifier (Parent (H)) = Partial_View
10378 end Overrides_Visible_Function;
10380 -- Start of processing for Check_Private_Overriding
10383 if Is_Package_Or_Generic_Package (Current_Scope)
10384 and then In_Private_Part (Current_Scope)
10385 and then Visible_Part_Type (T)
10386 and then not In_Instance
10388 if Is_Abstract_Type (T)
10389 and then Is_Abstract_Subprogram (S)
10390 and then (not Is_Overriding
10391 or else not Is_Abstract_Subprogram (E)
10392 or else Overrides_Private_Part_Op)
10395 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10398 elsif Ekind (S) = E_Function then
10400 Partial_View : constant Entity_Id :=
10401 Incomplete_Or_Partial_View (T);
10404 if not Overrides_Visible_Function (Partial_View) then
10406 -- Here, S is "function ... return T;" declared in
10407 -- the private part, not overriding some visible
10408 -- operation. That's illegal in the tagged case
10409 -- (but not if the private type is untagged).
10411 if ((Present (Partial_View)
10412 and then Is_Tagged_Type (Partial_View))
10413 or else (not Present (Partial_View)
10414 and then Is_Tagged_Type (T)))
10415 and then T = Base_Type (Etype (S))
10418 ("private function with tagged result must"
10419 & " override visible-part function", S);
10421 ("\move subprogram to the visible part"
10422 & " (RM 3.9.3(10))", S);
10424 -- AI05-0073: extend this test to the case of a
10425 -- function with a controlling access result.
10427 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10428 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10430 not Is_Class_Wide_Type
10431 (Designated_Type (Etype (S)))
10432 and then Ada_Version >= Ada_2012
10435 ("private function with controlling access "
10436 & "result must override visible-part function",
10439 ("\move subprogram to the visible part"
10440 & " (RM 3.9.3(10))", S);
10446 end Check_Private_Overriding;
10448 -----------------------
10449 -- Visible_Part_Type --
10450 -----------------------
10452 function Visible_Part_Type (T : Entity_Id) return Boolean is
10453 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10456 -- If the entity is a private type, then it must be declared in a
10459 if Ekind (T) in Private_Kind then
10462 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10465 elsif Is_List_Member (Declaration_Node (T))
10466 and then List_Containing (Declaration_Node (T)) =
10467 Visible_Declarations (Specification (P))
10474 end Visible_Part_Type;
10476 -- Start of processing for Check_For_Primitive_Subprogram
10479 Is_Primitive := False;
10481 if not Comes_From_Source (S) then
10484 -- If subprogram is at library level, it is not primitive operation
10486 elsif Current_Scope = Standard_Standard then
10489 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10490 and then not In_Package_Body (Current_Scope))
10491 or else Is_Overriding
10493 -- For function, check return type
10495 if Ekind (S) = E_Function then
10496 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10497 F_Typ := Designated_Type (Etype (S));
10499 F_Typ := Etype (S);
10502 B_Typ := Base_Type (F_Typ);
10504 if Scope (B_Typ) = Current_Scope
10505 and then not Is_Class_Wide_Type (B_Typ)
10506 and then not Is_Generic_Type (B_Typ)
10508 Is_Primitive := True;
10509 Set_Has_Primitive_Operations (B_Typ);
10510 Set_Is_Primitive (S);
10511 Check_Private_Overriding (B_Typ);
10513 -- The Ghost policy in effect at the point of declaration
10514 -- or a tagged type and a primitive operation must match
10515 -- (SPARK RM 6.9(16)).
10517 Check_Ghost_Primitive (S, B_Typ);
10521 -- For all subprograms, check formals
10523 Formal := First_Formal (S);
10524 while Present (Formal) loop
10525 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10526 F_Typ := Designated_Type (Etype (Formal));
10528 F_Typ := Etype (Formal);
10531 B_Typ := Base_Type (F_Typ);
10533 if Ekind (B_Typ) = E_Access_Subtype then
10534 B_Typ := Base_Type (B_Typ);
10537 if Scope (B_Typ) = Current_Scope
10538 and then not Is_Class_Wide_Type (B_Typ)
10539 and then not Is_Generic_Type (B_Typ)
10541 Is_Primitive := True;
10542 Set_Is_Primitive (S);
10543 Set_Has_Primitive_Operations (B_Typ);
10544 Check_Private_Overriding (B_Typ);
10546 -- The Ghost policy in effect at the point of declaration
10547 -- of a tagged type and a primitive operation must match
10548 -- (SPARK RM 6.9(16)).
10550 Check_Ghost_Primitive (S, B_Typ);
10553 Next_Formal (Formal);
10556 -- Special case: An equality function can be redefined for a type
10557 -- occurring in a declarative part, and won't otherwise be treated as
10558 -- a primitive because it doesn't occur in a package spec and doesn't
10559 -- override an inherited subprogram. It's important that we mark it
10560 -- primitive so it can be returned by Collect_Primitive_Operations
10561 -- and be used in composing the equality operation of later types
10562 -- that have a component of the type.
10564 elsif Chars (S) = Name_Op_Eq
10565 and then Etype (S) = Standard_Boolean
10567 B_Typ := Base_Type (Etype (First_Formal (S)));
10569 if Scope (B_Typ) = Current_Scope
10571 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10572 and then not Is_Limited_Type (B_Typ)
10574 Is_Primitive := True;
10575 Set_Is_Primitive (S);
10576 Set_Has_Primitive_Operations (B_Typ);
10577 Check_Private_Overriding (B_Typ);
10579 -- The Ghost policy in effect at the point of declaration of a
10580 -- tagged type and a primitive operation must match
10581 -- (SPARK RM 6.9(16)).
10583 Check_Ghost_Primitive (S, B_Typ);
10586 end Check_For_Primitive_Subprogram;
10588 --------------------------------------
10589 -- Has_Matching_Entry_Or_Subprogram --
10590 --------------------------------------
10592 function Has_Matching_Entry_Or_Subprogram
10593 (E : Entity_Id) return Boolean
10595 function Check_Conforming_Parameters
10596 (E1_Param : Node_Id;
10597 E2_Param : Node_Id;
10598 Ctype : Conformance_Type) return Boolean;
10599 -- Starting from the given parameters, check that all the parameters
10600 -- of two entries or subprograms are conformant. Used to skip
10601 -- the check on the controlling argument.
10603 function Matching_Entry_Or_Subprogram
10604 (Conc_Typ : Entity_Id;
10605 Subp : Entity_Id) return Entity_Id;
10606 -- Return the first entry or subprogram of the given concurrent type
10607 -- whose name matches the name of Subp and has a profile conformant
10608 -- with Subp; return Empty if not found.
10610 function Matching_Dispatching_Subprogram
10611 (Conc_Typ : Entity_Id;
10612 Ent : Entity_Id) return Entity_Id;
10613 -- Return the first dispatching primitive of Conc_Type defined in the
10614 -- enclosing scope of Conc_Type (i.e. before the full definition of
10615 -- this concurrent type) whose name matches the entry Ent and has a
10616 -- profile conformant with the profile of the corresponding (not yet
10617 -- built) dispatching primitive of Ent; return Empty if not found.
10619 function Matching_Original_Protected_Subprogram
10620 (Prot_Typ : Entity_Id;
10621 Subp : Entity_Id) return Entity_Id;
10622 -- Return the first subprogram defined in the enclosing scope of
10623 -- Prot_Typ (before the full definition of this protected type)
10624 -- whose name matches the original name of Subp and has a profile
10625 -- conformant with the profile of Subp; return Empty if not found.
10627 function Normalized_First_Parameter_Type
10628 (E : Entity_Id) return Entity_Id;
10629 -- Return the type of the first parameter unless that type
10630 -- is an anonymous access type, in which case return the
10631 -- designated type. Used to treat anonymous-access-to-synchronized
10632 -- the same as synchronized for purposes of checking for
10633 -- prefixed view profile conflicts.
10635 ---------------------------------
10636 -- Check_Conforming_Parameters --
10637 ---------------------------------
10639 function Check_Conforming_Parameters
10640 (E1_Param : Node_Id;
10641 E2_Param : Node_Id;
10642 Ctype : Conformance_Type) return Boolean
10644 Param_E1 : Node_Id := E1_Param;
10645 Param_E2 : Node_Id := E2_Param;
10648 while Present (Param_E1) and then Present (Param_E2) loop
10649 if (Ctype >= Mode_Conformant) and then
10650 Ekind (Defining_Identifier (Param_E1)) /=
10651 Ekind (Defining_Identifier (Param_E2))
10656 (Find_Parameter_Type (Param_E1),
10657 Find_Parameter_Type (Param_E2),
10667 -- The candidate is not valid if one of the two lists contains
10668 -- more parameters than the other
10670 return No (Param_E1) and then No (Param_E2);
10671 end Check_Conforming_Parameters;
10673 ----------------------------------
10674 -- Matching_Entry_Or_Subprogram --
10675 ----------------------------------
10677 function Matching_Entry_Or_Subprogram
10678 (Conc_Typ : Entity_Id;
10679 Subp : Entity_Id) return Entity_Id
10684 E := First_Entity (Conc_Typ);
10685 while Present (E) loop
10686 if Chars (Subp) = Chars (E)
10687 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10689 Check_Conforming_Parameters
10690 (First (Parameter_Specifications (Parent (E))),
10691 Next (First (Parameter_Specifications (Parent (Subp)))),
10701 end Matching_Entry_Or_Subprogram;
10703 -------------------------------------
10704 -- Matching_Dispatching_Subprogram --
10705 -------------------------------------
10707 function Matching_Dispatching_Subprogram
10708 (Conc_Typ : Entity_Id;
10709 Ent : Entity_Id) return Entity_Id
10714 -- Search for entities in the enclosing scope of this synchonized
10717 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10718 Push_Scope (Scope (Conc_Typ));
10719 E := Current_Entity_In_Scope (Ent);
10722 while Present (E) loop
10723 if Scope (E) = Scope (Conc_Typ)
10724 and then Comes_From_Source (E)
10725 and then Ekind (E) = E_Procedure
10726 and then Present (First_Entity (E))
10727 and then Is_Controlling_Formal (First_Entity (E))
10728 and then Etype (First_Entity (E)) = Conc_Typ
10730 Check_Conforming_Parameters
10731 (First (Parameter_Specifications (Parent (Ent))),
10732 Next (First (Parameter_Specifications (Parent (E)))),
10733 Subtype_Conformant)
10742 end Matching_Dispatching_Subprogram;
10744 --------------------------------------------
10745 -- Matching_Original_Protected_Subprogram --
10746 --------------------------------------------
10748 function Matching_Original_Protected_Subprogram
10749 (Prot_Typ : Entity_Id;
10750 Subp : Entity_Id) return Entity_Id
10752 ICF : constant Boolean :=
10753 Is_Controlling_Formal (First_Entity (Subp));
10757 -- Temporarily decorate the first parameter of Subp as controlling
10758 -- formal, required to invoke Subtype_Conformant.
10760 Set_Is_Controlling_Formal (First_Entity (Subp));
10763 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10765 while Present (E) loop
10766 if Scope (E) = Scope (Prot_Typ)
10767 and then Comes_From_Source (E)
10768 and then Ekind (Subp) = Ekind (E)
10769 and then Present (First_Entity (E))
10770 and then Is_Controlling_Formal (First_Entity (E))
10771 and then Etype (First_Entity (E)) = Prot_Typ
10772 and then Subtype_Conformant (Subp, E,
10773 Skip_Controlling_Formals => True)
10775 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10782 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10785 end Matching_Original_Protected_Subprogram;
10787 -------------------------------------
10788 -- Normalized_First_Parameter_Type --
10789 -------------------------------------
10791 function Normalized_First_Parameter_Type
10792 (E : Entity_Id) return Entity_Id
10794 Result : Entity_Id := Etype (First_Entity (E));
10796 if Ekind (Result) = E_Anonymous_Access_Type then
10797 Result := Designated_Type (Result);
10800 end Normalized_First_Parameter_Type;
10802 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10805 -- Case 1: E is a subprogram whose first formal is a concurrent type
10806 -- defined in the scope of E that has an entry or subprogram whose
10807 -- profile matches E.
10809 if Comes_From_Source (E)
10810 and then Is_Subprogram (E)
10811 and then Present (First_Entity (E))
10812 and then Is_Concurrent_Record_Type
10813 (Normalized_First_Parameter_Type (E))
10816 Scope (Corresponding_Concurrent_Type
10817 (Normalized_First_Parameter_Type (E)))
10820 (Matching_Entry_Or_Subprogram
10821 (Corresponding_Concurrent_Type
10822 (Normalized_First_Parameter_Type (E)),
10825 Report_Conflict (E,
10826 Matching_Entry_Or_Subprogram
10827 (Corresponding_Concurrent_Type
10828 (Normalized_First_Parameter_Type (E)),
10833 -- Case 2: E is an internally built dispatching subprogram of a
10834 -- protected type and there is a subprogram defined in the enclosing
10835 -- scope of the protected type that has the original name of E and
10836 -- its profile is conformant with the profile of E. We check the
10837 -- name of the original protected subprogram associated with E since
10838 -- the expander builds dispatching primitives of protected functions
10839 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10841 elsif not Comes_From_Source (E)
10842 and then Is_Subprogram (E)
10843 and then Present (First_Entity (E))
10844 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10845 and then Present (Original_Protected_Subprogram (E))
10848 (Matching_Original_Protected_Subprogram
10849 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10852 Report_Conflict (E,
10853 Matching_Original_Protected_Subprogram
10854 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10858 -- Case 3: E is an entry of a synchronized type and a matching
10859 -- procedure has been previously defined in the enclosing scope
10860 -- of the synchronized type.
10862 elsif Comes_From_Source (E)
10863 and then Ekind (E) = E_Entry
10865 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10867 Report_Conflict (E,
10868 Matching_Dispatching_Subprogram (Current_Scope, E));
10873 end Has_Matching_Entry_Or_Subprogram;
10875 ----------------------------
10876 -- Is_Private_Declaration --
10877 ----------------------------
10879 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10880 Decl : constant Node_Id := Unit_Declaration_Node (E);
10881 Priv_Decls : List_Id;
10884 if Is_Package_Or_Generic_Package (Current_Scope)
10885 and then In_Private_Part (Current_Scope)
10888 Private_Declarations (Package_Specification (Current_Scope));
10890 return In_Package_Body (Current_Scope)
10892 (Is_List_Member (Decl)
10893 and then List_Containing (Decl) = Priv_Decls)
10894 or else (Nkind (Parent (Decl)) = N_Package_Specification
10896 Is_Compilation_Unit
10897 (Defining_Entity (Parent (Decl)))
10898 and then List_Containing (Parent (Parent (Decl))) =
10903 end Is_Private_Declaration;
10905 --------------------------
10906 -- Is_Overriding_Alias --
10907 --------------------------
10909 function Is_Overriding_Alias
10910 (Old_E : Entity_Id;
10911 New_E : Entity_Id) return Boolean
10913 AO : constant Entity_Id := Alias (Old_E);
10914 AN : constant Entity_Id := Alias (New_E);
10917 return Scope (AO) /= Scope (AN)
10918 or else No (DTC_Entity (AO))
10919 or else No (DTC_Entity (AN))
10920 or else DT_Position (AO) = DT_Position (AN);
10921 end Is_Overriding_Alias;
10923 ---------------------
10924 -- Report_Conflict --
10925 ---------------------
10927 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10929 Error_Msg_Sloc := Sloc (E);
10931 -- Generate message, with useful additional warning if in generic
10933 if Is_Generic_Unit (E) then
10934 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10935 Error_Msg_N ("\& conflicts with declaration#", S);
10937 Error_Msg_N ("& conflicts with declaration#", S);
10939 end Report_Conflict;
10941 -- Start of processing for New_Overloaded_Entity
10944 -- We need to look for an entity that S may override. This must be a
10945 -- homonym in the current scope, so we look for the first homonym of
10946 -- S in the current scope as the starting point for the search.
10948 E := Current_Entity_In_Scope (S);
10950 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10951 -- They are directly added to the list of primitive operations of
10952 -- Derived_Type, unless this is a rederivation in the private part
10953 -- of an operation that was already derived in the visible part of
10954 -- the current package.
10956 if Ada_Version >= Ada_2005
10957 and then Present (Derived_Type)
10958 and then Present (Alias (S))
10959 and then Is_Dispatching_Operation (Alias (S))
10960 and then Present (Find_Dispatching_Type (Alias (S)))
10961 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10963 -- For private types, when the full-view is processed we propagate to
10964 -- the full view the non-overridden entities whose attribute "alias"
10965 -- references an interface primitive. These entities were added by
10966 -- Derive_Subprograms to ensure that interface primitives are
10969 -- Inside_Freeze_Actions is non zero when S corresponds with an
10970 -- internal entity that links an interface primitive with its
10971 -- covering primitive through attribute Interface_Alias (see
10972 -- Add_Internal_Interface_Entities).
10974 if Inside_Freezing_Actions = 0
10975 and then Is_Package_Or_Generic_Package (Current_Scope)
10976 and then In_Private_Part (Current_Scope)
10977 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10978 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10979 and then Full_View (Defining_Identifier (Parent (E)))
10980 = Defining_Identifier (Parent (S))
10981 and then Alias (E) = Alias (S)
10983 Check_Operation_From_Private_View (S, E);
10984 Set_Is_Dispatching_Operation (S);
10989 Enter_Overloaded_Entity (S);
10990 Check_Dispatching_Operation (S, Empty);
10991 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10997 -- For synchronized types check conflicts of this entity with previously
10998 -- defined entities.
11000 if Ada_Version >= Ada_2005
11001 and then Has_Matching_Entry_Or_Subprogram (S)
11006 -- If there is no homonym then this is definitely not overriding
11009 Enter_Overloaded_Entity (S);
11010 Check_Dispatching_Operation (S, Empty);
11011 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11013 -- If subprogram has an explicit declaration, check whether it has an
11014 -- overriding indicator.
11016 if Comes_From_Source (S) then
11017 Check_Synchronized_Overriding (S, Overridden_Subp);
11019 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
11020 -- it may have overridden some hidden inherited primitive. Update
11021 -- Overridden_Subp to avoid spurious errors when checking the
11022 -- overriding indicator.
11024 if Ada_Version >= Ada_2012
11025 and then No (Overridden_Subp)
11026 and then Is_Dispatching_Operation (S)
11027 and then Present (Overridden_Operation (S))
11029 Overridden_Subp := Overridden_Operation (S);
11032 Check_Overriding_Indicator
11033 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11035 -- The Ghost policy in effect at the point of declaration of a
11036 -- parent subprogram and an overriding subprogram must match
11037 -- (SPARK RM 6.9(17)).
11039 Check_Ghost_Overriding (S, Overridden_Subp);
11042 -- If there is a homonym that is not overloadable, then we have an
11043 -- error, except for the special cases checked explicitly below.
11045 elsif not Is_Overloadable (E) then
11047 -- Check for spurious conflict produced by a subprogram that has the
11048 -- same name as that of the enclosing generic package. The conflict
11049 -- occurs within an instance, between the subprogram and the renaming
11050 -- declaration for the package. After the subprogram, the package
11051 -- renaming declaration becomes hidden.
11053 if Ekind (E) = E_Package
11054 and then Present (Renamed_Object (E))
11055 and then Renamed_Object (E) = Current_Scope
11056 and then Nkind (Parent (Renamed_Object (E))) =
11057 N_Package_Specification
11058 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
11061 Set_Is_Immediately_Visible (E, False);
11062 Enter_Overloaded_Entity (S);
11063 Set_Homonym (S, Homonym (E));
11064 Check_Dispatching_Operation (S, Empty);
11065 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
11067 -- If the subprogram is implicit it is hidden by the previous
11068 -- declaration. However if it is dispatching, it must appear in the
11069 -- dispatch table anyway, because it can be dispatched to even if it
11070 -- cannot be called directly.
11072 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
11073 Set_Scope (S, Current_Scope);
11075 if Is_Dispatching_Operation (Alias (S)) then
11076 Check_Dispatching_Operation (S, Empty);
11082 Report_Conflict (S, E);
11086 -- E exists and is overloadable
11089 Check_Synchronized_Overriding (S, Overridden_Subp);
11091 -- Loop through E and its homonyms to determine if any of them is
11092 -- the candidate for overriding by S.
11094 while Present (E) loop
11096 -- Definitely not interesting if not in the current scope
11098 if Scope (E) /= Current_Scope then
11101 -- A function can overload the name of an abstract state. The
11102 -- state can be viewed as a function with a profile that cannot
11103 -- be matched by anything.
11105 elsif Ekind (S) = E_Function
11106 and then Ekind (E) = E_Abstract_State
11108 Enter_Overloaded_Entity (S);
11111 -- Ada 2012 (AI05-0165): For internally generated bodies of null
11112 -- procedures locate the internally generated spec. We enforce
11113 -- mode conformance since a tagged type may inherit from
11114 -- interfaces several null primitives which differ only in
11115 -- the mode of the formals.
11117 elsif not Comes_From_Source (S)
11118 and then Is_Null_Procedure (S)
11119 and then not Mode_Conformant (E, S)
11123 -- Check if we have type conformance
11125 elsif Type_Conformant (E, S) then
11127 -- If the old and new entities have the same profile and one
11128 -- is not the body of the other, then this is an error, unless
11129 -- one of them is implicitly declared.
11131 -- There are some cases when both can be implicit, for example
11132 -- when both a literal and a function that overrides it are
11133 -- inherited in a derivation, or when an inherited operation
11134 -- of a tagged full type overrides the inherited operation of
11135 -- a private extension. Ada 83 had a special rule for the
11136 -- literal case. In Ada 95, the later implicit operation hides
11137 -- the former, and the literal is always the former. In the
11138 -- odd case where both are derived operations declared at the
11139 -- same point, both operations should be declared, and in that
11140 -- case we bypass the following test and proceed to the next
11141 -- part. This can only occur for certain obscure cases in
11142 -- instances, when an operation on a type derived from a formal
11143 -- private type does not override a homograph inherited from
11144 -- the actual. In subsequent derivations of such a type, the
11145 -- DT positions of these operations remain distinct, if they
11148 if Present (Alias (S))
11149 and then (No (Alias (E))
11150 or else Comes_From_Source (E)
11151 or else Is_Abstract_Subprogram (S)
11153 (Is_Dispatching_Operation (E)
11154 and then Is_Overriding_Alias (E, S)))
11155 and then Ekind (E) /= E_Enumeration_Literal
11157 -- When an derived operation is overloaded it may be due to
11158 -- the fact that the full view of a private extension
11159 -- re-inherits. It has to be dealt with.
11161 if Is_Package_Or_Generic_Package (Current_Scope)
11162 and then In_Private_Part (Current_Scope)
11164 Check_Operation_From_Private_View (S, E);
11167 -- In any case the implicit operation remains hidden by the
11168 -- existing declaration, which is overriding. Indicate that
11169 -- E overrides the operation from which S is inherited.
11171 if Present (Alias (S)) then
11172 Set_Overridden_Operation (E, Alias (S));
11173 Inherit_Subprogram_Contract (E, Alias (S));
11176 Set_Overridden_Operation (E, S);
11177 Inherit_Subprogram_Contract (E, S);
11180 if Comes_From_Source (E) then
11181 Check_Overriding_Indicator (E, S, Is_Primitive => False);
11183 -- The Ghost policy in effect at the point of declaration
11184 -- of a parent subprogram and an overriding subprogram
11185 -- must match (SPARK RM 6.9(17)).
11187 Check_Ghost_Overriding (E, S);
11192 -- Within an instance, the renaming declarations for actual
11193 -- subprograms may become ambiguous, but they do not hide each
11196 elsif Ekind (E) /= E_Entry
11197 and then not Comes_From_Source (E)
11198 and then not Is_Generic_Instance (E)
11199 and then (Present (Alias (E))
11200 or else Is_Intrinsic_Subprogram (E))
11201 and then (not In_Instance
11202 or else No (Parent (E))
11203 or else Nkind (Unit_Declaration_Node (E)) /=
11204 N_Subprogram_Renaming_Declaration)
11206 -- A subprogram child unit is not allowed to override an
11207 -- inherited subprogram (10.1.1(20)).
11209 if Is_Child_Unit (S) then
11211 ("child unit overrides inherited subprogram in parent",
11216 if Is_Non_Overriding_Operation (E, S) then
11217 Enter_Overloaded_Entity (S);
11219 if No (Derived_Type)
11220 or else Is_Tagged_Type (Derived_Type)
11222 Check_Dispatching_Operation (S, Empty);
11228 -- E is a derived operation or an internal operator which
11229 -- is being overridden. Remove E from further visibility.
11230 -- Furthermore, if E is a dispatching operation, it must be
11231 -- replaced in the list of primitive operations of its type
11232 -- (see Override_Dispatching_Operation).
11234 Overridden_Subp := E;
11236 -- It is possible for E to be in the current scope and
11237 -- yet not in the entity chain. This can only occur in a
11238 -- generic context where E is an implicit concatenation
11239 -- in the formal part, because in a generic body the
11240 -- entity chain starts with the formals.
11242 -- In GNATprove mode, a wrapper for an operation with
11243 -- axiomatization may be a homonym of another declaration
11244 -- for an actual subprogram (needs refinement ???).
11246 if No (Prev_Entity (E)) then
11248 and then GNATprove_Mode
11250 Nkind (Original_Node (Unit_Declaration_Node (S))) =
11251 N_Subprogram_Renaming_Declaration
11255 pragma Assert (Chars (E) = Name_Op_Concat);
11260 -- E must be removed both from the entity_list of the
11261 -- current scope, and from the visibility chain.
11263 if Debug_Flag_E then
11264 Write_Str ("Override implicit operation ");
11265 Write_Int (Int (E));
11269 -- If E is a predefined concatenation, it stands for four
11270 -- different operations. As a result, a single explicit
11271 -- declaration does not hide it. In a possible ambiguous
11272 -- situation, Disambiguate chooses the user-defined op,
11273 -- so it is correct to retain the previous internal one.
11275 if Chars (E) /= Name_Op_Concat
11276 or else Ekind (E) /= E_Operator
11278 -- For nondispatching derived operations that are
11279 -- overridden by a subprogram declared in the private
11280 -- part of a package, we retain the derived subprogram
11281 -- but mark it as not immediately visible. If the
11282 -- derived operation was declared in the visible part
11283 -- then this ensures that it will still be visible
11284 -- outside the package with the proper signature
11285 -- (calls from outside must also be directed to this
11286 -- version rather than the overriding one, unlike the
11287 -- dispatching case). Calls from inside the package
11288 -- will still resolve to the overriding subprogram
11289 -- since the derived one is marked as not visible
11290 -- within the package.
11292 -- If the private operation is dispatching, we achieve
11293 -- the overriding by keeping the implicit operation
11294 -- but setting its alias to be the overriding one. In
11295 -- this fashion the proper body is executed in all
11296 -- cases, but the original signature is used outside
11299 -- If the overriding is not in the private part, we
11300 -- remove the implicit operation altogether.
11302 if Is_Private_Declaration (S) then
11303 if not Is_Dispatching_Operation (E) then
11304 Set_Is_Immediately_Visible (E, False);
11306 -- Work done in Override_Dispatching_Operation, so
11307 -- nothing else needs to be done here.
11313 Remove_Entity_And_Homonym (E);
11317 Enter_Overloaded_Entity (S);
11319 -- For entities generated by Derive_Subprograms the
11320 -- overridden operation is the inherited primitive
11321 -- (which is available through the attribute alias).
11323 if not (Comes_From_Source (E))
11324 and then Is_Dispatching_Operation (E)
11325 and then Find_Dispatching_Type (E) =
11326 Find_Dispatching_Type (S)
11327 and then Present (Alias (E))
11328 and then Comes_From_Source (Alias (E))
11330 Set_Overridden_Operation (S, Alias (E));
11331 Inherit_Subprogram_Contract (S, Alias (E));
11333 -- Normal case of setting entity as overridden
11335 -- Note: Static_Initialization and Overridden_Operation
11336 -- attributes use the same field in subprogram entities.
11337 -- Static_Initialization is only defined for internal
11338 -- initialization procedures, where Overridden_Operation
11339 -- is irrelevant. Therefore the setting of this attribute
11340 -- must check whether the target is an init_proc.
11342 elsif not Is_Init_Proc (S) then
11343 Set_Overridden_Operation (S, E);
11344 Inherit_Subprogram_Contract (S, E);
11347 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11349 -- The Ghost policy in effect at the point of declaration
11350 -- of a parent subprogram and an overriding subprogram
11351 -- must match (SPARK RM 6.9(17)).
11353 Check_Ghost_Overriding (S, E);
11355 -- If S is a user-defined subprogram or a null procedure
11356 -- expanded to override an inherited null procedure, or a
11357 -- predefined dispatching primitive then indicate that E
11358 -- overrides the operation from which S is inherited.
11360 if Comes_From_Source (S)
11362 (Present (Parent (S))
11363 and then Nkind (Parent (S)) = N_Procedure_Specification
11364 and then Null_Present (Parent (S)))
11366 (Present (Alias (E))
11368 Is_Predefined_Dispatching_Operation (Alias (E)))
11370 if Present (Alias (E)) then
11371 Set_Overridden_Operation (S, Alias (E));
11372 Inherit_Subprogram_Contract (S, Alias (E));
11376 if Is_Dispatching_Operation (E) then
11378 -- An overriding dispatching subprogram inherits the
11379 -- convention of the overridden subprogram (AI-117).
11381 Set_Convention (S, Convention (E));
11382 Check_Dispatching_Operation (S, E);
11385 Check_Dispatching_Operation (S, Empty);
11388 Check_For_Primitive_Subprogram
11389 (Is_Primitive_Subp, Is_Overriding => True);
11390 goto Check_Inequality;
11392 -- Apparent redeclarations in instances can occur when two
11393 -- formal types get the same actual type. The subprograms in
11394 -- in the instance are legal, even if not callable from the
11395 -- outside. Calls from within are disambiguated elsewhere.
11396 -- For dispatching operations in the visible part, the usual
11397 -- rules apply, and operations with the same profile are not
11398 -- legal (B830001).
11400 elsif (In_Instance_Visible_Part
11401 and then not Is_Dispatching_Operation (E))
11402 or else In_Instance_Not_Visible
11406 -- Here we have a real error (identical profile)
11409 Error_Msg_Sloc := Sloc (E);
11411 -- Avoid cascaded errors if the entity appears in
11412 -- subsequent calls.
11414 Set_Scope (S, Current_Scope);
11416 -- Generate error, with extra useful warning for the case
11417 -- of a generic instance with no completion.
11419 if Is_Generic_Instance (S)
11420 and then not Has_Completion (E)
11423 ("instantiation cannot provide body for&", S);
11424 Error_Msg_N ("\& conflicts with declaration#", S);
11426 Error_Msg_N ("& conflicts with declaration#", S);
11433 -- If one subprogram has an access parameter and the other
11434 -- a parameter of an access type, calls to either might be
11435 -- ambiguous. Verify that parameters match except for the
11436 -- access parameter.
11438 if May_Hide_Profile then
11444 F1 := First_Formal (S);
11445 F2 := First_Formal (E);
11446 while Present (F1) and then Present (F2) loop
11447 if Is_Access_Type (Etype (F1)) then
11448 if not Is_Access_Type (Etype (F2))
11449 or else not Conforming_Types
11450 (Designated_Type (Etype (F1)),
11451 Designated_Type (Etype (F2)),
11454 May_Hide_Profile := False;
11458 not Conforming_Types
11459 (Etype (F1), Etype (F2), Type_Conformant)
11461 May_Hide_Profile := False;
11468 if May_Hide_Profile
11472 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11481 -- On exit, we know that S is a new entity
11483 Enter_Overloaded_Entity (S);
11484 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11485 Check_Overriding_Indicator
11486 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11488 -- The Ghost policy in effect at the point of declaration of a parent
11489 -- subprogram and an overriding subprogram must match
11490 -- (SPARK RM 6.9(17)).
11492 Check_Ghost_Overriding (S, Overridden_Subp);
11494 -- If S is a derived operation for an untagged type then by
11495 -- definition it's not a dispatching operation (even if the parent
11496 -- operation was dispatching), so Check_Dispatching_Operation is not
11497 -- called in that case.
11499 if No (Derived_Type)
11500 or else Is_Tagged_Type (Derived_Type)
11502 Check_Dispatching_Operation (S, Empty);
11506 -- If this is a user-defined equality operator that is not a derived
11507 -- subprogram, create the corresponding inequality. If the operation is
11508 -- dispatching, the expansion is done elsewhere, and we do not create
11509 -- an explicit inequality operation.
11511 <<Check_Inequality>>
11512 if Chars (S) = Name_Op_Eq
11513 and then Etype (S) = Standard_Boolean
11514 and then Present (Parent (S))
11515 and then not Is_Dispatching_Operation (S)
11517 Make_Inequality_Operator (S);
11518 Check_Untagged_Equality (S);
11520 end New_Overloaded_Entity;
11522 ----------------------------------
11523 -- Preanalyze_Formal_Expression --
11524 ----------------------------------
11526 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id) is
11527 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
11529 In_Spec_Expression := True;
11530 Preanalyze_With_Freezing_And_Resolve (N, T);
11531 In_Spec_Expression := Save_In_Spec_Expression;
11532 end Preanalyze_Formal_Expression;
11534 ---------------------
11535 -- Process_Formals --
11536 ---------------------
11538 procedure Process_Formals
11540 Related_Nod : Node_Id)
11542 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11543 -- Determine whether an access type designates a type coming from a
11546 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11547 -- Check whether the default has a class-wide type. After analysis the
11548 -- default has the type of the formal, so we must also check explicitly
11549 -- for an access attribute.
11551 ----------------------------------
11552 -- Designates_From_Limited_With --
11553 ----------------------------------
11555 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11556 Desig : Entity_Id := Typ;
11559 if Is_Access_Type (Desig) then
11560 Desig := Directly_Designated_Type (Desig);
11563 if Is_Class_Wide_Type (Desig) then
11564 Desig := Root_Type (Desig);
11568 Ekind (Desig) = E_Incomplete_Type
11569 and then From_Limited_With (Desig);
11570 end Designates_From_Limited_With;
11572 ---------------------------
11573 -- Is_Class_Wide_Default --
11574 ---------------------------
11576 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11578 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11579 or else (Nkind (D) = N_Attribute_Reference
11580 and then Attribute_Name (D) = Name_Access
11581 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11582 end Is_Class_Wide_Default;
11586 Context : constant Node_Id := Parent (Parent (T));
11588 Formal : Entity_Id;
11589 Formal_Type : Entity_Id;
11590 Param_Spec : Node_Id;
11593 Num_Out_Params : Nat := 0;
11594 First_Out_Param : Entity_Id := Empty;
11595 -- Used for setting Is_Only_Out_Parameter
11597 -- Start of processing for Process_Formals
11600 -- In order to prevent premature use of the formals in the same formal
11601 -- part, the Ekind is left undefined until all default expressions are
11602 -- analyzed. The Ekind is established in a separate loop at the end.
11604 Param_Spec := First (T);
11605 while Present (Param_Spec) loop
11606 Formal := Defining_Identifier (Param_Spec);
11607 Set_Never_Set_In_Source (Formal, True);
11608 Enter_Name (Formal);
11610 -- Case of ordinary parameters
11612 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11613 Find_Type (Parameter_Type (Param_Spec));
11614 Ptype := Parameter_Type (Param_Spec);
11616 if Ptype = Error then
11620 -- Protect against malformed parameter types
11622 if Nkind (Ptype) not in N_Has_Entity then
11623 Formal_Type := Any_Type;
11625 Formal_Type := Entity (Ptype);
11628 if Is_Incomplete_Type (Formal_Type)
11630 (Is_Class_Wide_Type (Formal_Type)
11631 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11633 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11634 -- primitive operations, as long as their completion is
11635 -- in the same declarative part. If in the private part
11636 -- this means that the type cannot be a Taft-amendment type.
11637 -- Check is done on package exit. For access to subprograms,
11638 -- the use is legal for Taft-amendment types.
11640 -- Ada 2012: tagged incomplete types are allowed as generic
11641 -- formal types. They do not introduce dependencies and the
11642 -- corresponding generic subprogram does not have a delayed
11643 -- freeze, because it does not need a freeze node. However,
11644 -- it is still the case that untagged incomplete types cannot
11645 -- be Taft-amendment types and must be completed in private
11646 -- part, so the subprogram must appear in the list of private
11647 -- dependents of the type.
11649 if Is_Tagged_Type (Formal_Type)
11650 or else (Ada_Version >= Ada_2012
11651 and then not From_Limited_With (Formal_Type)
11652 and then not Is_Generic_Type (Formal_Type))
11654 if Ekind (Scope (Current_Scope)) = E_Package
11655 and then not Is_Generic_Type (Formal_Type)
11656 and then not Is_Class_Wide_Type (Formal_Type)
11659 (Parent (T), N_Access_Function_Definition,
11660 N_Access_Procedure_Definition)
11662 Append_Elmt (Current_Scope,
11663 Private_Dependents (Base_Type (Formal_Type)));
11665 -- Freezing is delayed to ensure that Register_Prim
11666 -- will get called for this operation, which is needed
11667 -- in cases where static dispatch tables aren't built.
11668 -- (Note that the same is done for controlling access
11669 -- parameter cases in function Access_Definition.)
11671 if not Is_Thunk (Current_Scope) then
11672 Set_Has_Delayed_Freeze (Current_Scope);
11677 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11678 N_Access_Procedure_Definition)
11680 -- AI05-0151: Tagged incomplete types are allowed in all
11681 -- formal parts. Untagged incomplete types are not allowed
11682 -- in bodies. Limited views of either kind are not allowed
11683 -- if there is no place at which the non-limited view can
11684 -- become available.
11686 -- Incomplete formal untagged types are not allowed in
11687 -- subprogram bodies (but are legal in their declarations).
11688 -- This excludes bodies created for null procedures, which
11689 -- are basic declarations.
11691 if Is_Generic_Type (Formal_Type)
11692 and then not Is_Tagged_Type (Formal_Type)
11693 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11696 ("invalid use of formal incomplete type", Param_Spec);
11698 elsif Ada_Version >= Ada_2012 then
11699 if Is_Tagged_Type (Formal_Type)
11700 and then (not From_Limited_With (Formal_Type)
11701 or else not In_Package_Body)
11705 elsif Nkind_In (Context, N_Accept_Statement,
11706 N_Accept_Alternative,
11708 or else (Nkind (Context) = N_Subprogram_Body
11709 and then Comes_From_Source (Context))
11712 ("invalid use of untagged incomplete type &",
11713 Ptype, Formal_Type);
11718 ("invalid use of incomplete type&",
11719 Param_Spec, Formal_Type);
11721 -- Further checks on the legality of incomplete types
11722 -- in formal parts are delayed until the freeze point
11723 -- of the enclosing subprogram or access to subprogram.
11727 elsif Ekind (Formal_Type) = E_Void then
11729 ("premature use of&",
11730 Parameter_Type (Param_Spec), Formal_Type);
11733 -- Ada 2012 (AI-142): Handle aliased parameters
11735 if Ada_Version >= Ada_2012
11736 and then Aliased_Present (Param_Spec)
11738 Set_Is_Aliased (Formal);
11740 -- AI12-001: All aliased objects are considered to be specified
11741 -- as independently addressable (RM C.6(8.1/4)).
11743 Set_Is_Independent (Formal);
11746 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11747 -- declaration corresponding to the null-excluding type of the
11748 -- formal in the enclosing scope. Finally, replace the parameter
11749 -- type of the formal with the internal subtype.
11751 if Ada_Version >= Ada_2005
11752 and then Null_Exclusion_Present (Param_Spec)
11754 if not Is_Access_Type (Formal_Type) then
11756 ("`NOT NULL` allowed only for an access type", Param_Spec);
11759 if Can_Never_Be_Null (Formal_Type)
11760 and then Comes_From_Source (Related_Nod)
11763 ("`NOT NULL` not allowed (& already excludes null)",
11764 Param_Spec, Formal_Type);
11768 Create_Null_Excluding_Itype
11770 Related_Nod => Related_Nod,
11771 Scope_Id => Scope (Current_Scope));
11773 -- If the designated type of the itype is an itype that is
11774 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11775 -- on the access subtype, to prevent order-of-elaboration
11776 -- issues in the backend.
11779 -- type T is access procedure;
11780 -- procedure Op (O : not null T);
11782 if Is_Itype (Directly_Designated_Type (Formal_Type))
11784 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11786 Set_Has_Delayed_Freeze (Formal_Type);
11791 -- An access formal type
11795 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11797 -- No need to continue if we already notified errors
11799 if not Present (Formal_Type) then
11803 -- Ada 2005 (AI-254)
11806 AD : constant Node_Id :=
11807 Access_To_Subprogram_Definition
11808 (Parameter_Type (Param_Spec));
11810 if Present (AD) and then Protected_Present (AD) then
11812 Replace_Anonymous_Access_To_Protected_Subprogram
11818 Set_Etype (Formal, Formal_Type);
11820 -- Deal with default expression if present
11822 Default := Expression (Param_Spec);
11824 if Present (Default) then
11825 if Out_Present (Param_Spec) then
11827 ("default initialization only allowed for IN parameters",
11831 -- Do the special preanalysis of the expression (see section on
11832 -- "Handling of Default Expressions" in the spec of package Sem).
11834 Preanalyze_Formal_Expression (Default, Formal_Type);
11836 -- An access to constant cannot be the default for
11837 -- an access parameter that is an access to variable.
11839 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11840 and then not Is_Access_Constant (Formal_Type)
11841 and then Is_Access_Type (Etype (Default))
11842 and then Is_Access_Constant (Etype (Default))
11845 ("formal that is access to variable cannot be initialized "
11846 & "with an access-to-constant expression", Default);
11849 -- Check that the designated type of an access parameter's default
11850 -- is not a class-wide type unless the parameter's designated type
11851 -- is also class-wide.
11853 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11854 and then not Designates_From_Limited_With (Formal_Type)
11855 and then Is_Class_Wide_Default (Default)
11856 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11859 ("access to class-wide expression not allowed here", Default);
11862 -- Check incorrect use of dynamically tagged expressions
11864 if Is_Tagged_Type (Formal_Type) then
11865 Check_Dynamically_Tagged_Expression
11867 Typ => Formal_Type,
11868 Related_Nod => Default);
11872 -- Ada 2005 (AI-231): Static checks
11874 if Ada_Version >= Ada_2005
11875 and then Is_Access_Type (Etype (Formal))
11876 and then Can_Never_Be_Null (Etype (Formal))
11878 Null_Exclusion_Static_Checks (Param_Spec);
11881 -- The following checks are relevant only when SPARK_Mode is on as
11882 -- these are not standard Ada legality rules.
11884 if SPARK_Mode = On then
11885 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11887 -- A function cannot have a parameter of mode IN OUT or OUT
11890 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11892 ("function cannot have parameter of mode `OUT` or "
11893 & "`IN OUT`", Formal);
11896 -- A procedure cannot have an effectively volatile formal
11897 -- parameter of mode IN because it behaves as a constant
11898 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11900 elsif Ekind (Scope (Formal)) = E_Procedure
11901 and then Ekind (Formal) = E_In_Parameter
11902 and then Is_Effectively_Volatile (Formal)
11905 ("formal parameter of mode `IN` cannot be volatile", Formal);
11913 -- If this is the formal part of a function specification, analyze the
11914 -- subtype mark in the context where the formals are visible but not
11915 -- yet usable, and may hide outer homographs.
11917 if Nkind (Related_Nod) = N_Function_Specification then
11918 Analyze_Return_Type (Related_Nod);
11921 -- Now set the kind (mode) of each formal
11923 Param_Spec := First (T);
11924 while Present (Param_Spec) loop
11925 Formal := Defining_Identifier (Param_Spec);
11926 Set_Formal_Mode (Formal);
11928 if Ekind (Formal) = E_In_Parameter then
11929 Set_Default_Value (Formal, Expression (Param_Spec));
11931 if Present (Expression (Param_Spec)) then
11932 Default := Expression (Param_Spec);
11934 if Is_Scalar_Type (Etype (Default)) then
11935 if Nkind (Parameter_Type (Param_Spec)) /=
11936 N_Access_Definition
11938 Formal_Type := Entity (Parameter_Type (Param_Spec));
11942 (Related_Nod, Parameter_Type (Param_Spec));
11945 Apply_Scalar_Range_Check (Default, Formal_Type);
11949 elsif Ekind (Formal) = E_Out_Parameter then
11950 Num_Out_Params := Num_Out_Params + 1;
11952 if Num_Out_Params = 1 then
11953 First_Out_Param := Formal;
11956 elsif Ekind (Formal) = E_In_Out_Parameter then
11957 Num_Out_Params := Num_Out_Params + 1;
11960 -- Skip remaining processing if formal type was in error
11962 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11963 goto Next_Parameter;
11966 -- Force call by reference if aliased
11969 Conv : constant Convention_Id := Convention (Etype (Formal));
11971 if Is_Aliased (Formal) then
11972 Set_Mechanism (Formal, By_Reference);
11974 -- Warn if user asked this to be passed by copy
11976 if Conv = Convention_Ada_Pass_By_Copy then
11978 ("cannot pass aliased parameter & by copy??", Formal);
11981 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11983 elsif Conv = Convention_Ada_Pass_By_Copy then
11984 Set_Mechanism (Formal, By_Copy);
11986 elsif Conv = Convention_Ada_Pass_By_Reference then
11987 Set_Mechanism (Formal, By_Reference);
11995 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11996 Set_Is_Only_Out_Parameter (First_Out_Param);
11998 end Process_Formals;
12000 ----------------------------
12001 -- Reference_Body_Formals --
12002 ----------------------------
12004 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
12009 if Error_Posted (Spec) then
12013 -- Iterate over both lists. They may be of different lengths if the two
12014 -- specs are not conformant.
12016 Fs := First_Formal (Spec);
12017 Fb := First_Formal (Bod);
12018 while Present (Fs) and then Present (Fb) loop
12019 Generate_Reference (Fs, Fb, 'b');
12021 if Style_Check then
12022 Style.Check_Identifier (Fb, Fs);
12025 Set_Spec_Entity (Fb, Fs);
12026 Set_Referenced (Fs, False);
12030 end Reference_Body_Formals;
12032 -------------------------
12033 -- Set_Actual_Subtypes --
12034 -------------------------
12036 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
12038 Formal : Entity_Id;
12040 First_Stmt : Node_Id := Empty;
12041 AS_Needed : Boolean;
12044 -- If this is an empty initialization procedure, no need to create
12045 -- actual subtypes (small optimization).
12047 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
12050 -- Within a predicate function we do not want to generate local
12051 -- subtypes that may generate nested predicate functions.
12053 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
12057 -- The subtype declarations may freeze the formals. The body generated
12058 -- for an expression function is not a freeze point, so do not emit
12059 -- these declarations (small loss of efficiency in rare cases).
12061 if Nkind (N) = N_Subprogram_Body
12062 and then Was_Expression_Function (N)
12067 Formal := First_Formal (Subp);
12068 while Present (Formal) loop
12069 T := Etype (Formal);
12071 -- We never need an actual subtype for a constrained formal
12073 if Is_Constrained (T) then
12074 AS_Needed := False;
12076 -- If we have unknown discriminants, then we do not need an actual
12077 -- subtype, or more accurately we cannot figure it out. Note that
12078 -- all class-wide types have unknown discriminants.
12080 elsif Has_Unknown_Discriminants (T) then
12081 AS_Needed := False;
12083 -- At this stage we have an unconstrained type that may need an
12084 -- actual subtype. For sure the actual subtype is needed if we have
12085 -- an unconstrained array type. However, in an instance, the type
12086 -- may appear as a subtype of the full view, while the actual is
12087 -- in fact private (in which case no actual subtype is needed) so
12088 -- check the kind of the base type.
12090 elsif Is_Array_Type (Base_Type (T)) then
12093 -- The only other case needing an actual subtype is an unconstrained
12094 -- record type which is an IN parameter (we cannot generate actual
12095 -- subtypes for the OUT or IN OUT case, since an assignment can
12096 -- change the discriminant values. However we exclude the case of
12097 -- initialization procedures, since discriminants are handled very
12098 -- specially in this context, see the section entitled "Handling of
12099 -- Discriminants" in Einfo.
12101 -- We also exclude the case of Discrim_SO_Functions (functions used
12102 -- in front-end layout mode for size/offset values), since in such
12103 -- functions only discriminants are referenced, and not only are such
12104 -- subtypes not needed, but they cannot always be generated, because
12105 -- of order of elaboration issues.
12107 elsif Is_Record_Type (T)
12108 and then Ekind (Formal) = E_In_Parameter
12109 and then Chars (Formal) /= Name_uInit
12110 and then not Is_Unchecked_Union (T)
12111 and then not Is_Discrim_SO_Function (Subp)
12115 -- All other cases do not need an actual subtype
12118 AS_Needed := False;
12121 -- Generate actual subtypes for unconstrained arrays and
12122 -- unconstrained discriminated records.
12125 if Nkind (N) = N_Accept_Statement then
12127 -- If expansion is active, the formal is replaced by a local
12128 -- variable that renames the corresponding entry of the
12129 -- parameter block, and it is this local variable that may
12130 -- require an actual subtype.
12132 if Expander_Active then
12133 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
12135 Decl := Build_Actual_Subtype (T, Formal);
12138 if Present (Handled_Statement_Sequence (N)) then
12140 First (Statements (Handled_Statement_Sequence (N)));
12141 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
12142 Mark_Rewrite_Insertion (Decl);
12144 -- If the accept statement has no body, there will be no
12145 -- reference to the actuals, so no need to compute actual
12152 Decl := Build_Actual_Subtype (T, Formal);
12153 Prepend (Decl, Declarations (N));
12154 Mark_Rewrite_Insertion (Decl);
12157 -- The declaration uses the bounds of an existing object, and
12158 -- therefore needs no constraint checks.
12160 Analyze (Decl, Suppress => All_Checks);
12161 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
12163 -- We need to freeze manually the generated type when it is
12164 -- inserted anywhere else than in a declarative part.
12166 if Present (First_Stmt) then
12167 Insert_List_Before_And_Analyze (First_Stmt,
12168 Freeze_Entity (Defining_Identifier (Decl), N));
12170 -- Ditto if the type has a dynamic predicate, because the
12171 -- generated function will mention the actual subtype. The
12172 -- predicate may come from an explicit aspect of be inherited.
12174 elsif Has_Predicates (T) then
12175 Insert_List_After_And_Analyze (Decl,
12176 Freeze_Entity (Defining_Identifier (Decl), N));
12179 if Nkind (N) = N_Accept_Statement
12180 and then Expander_Active
12182 Set_Actual_Subtype (Renamed_Object (Formal),
12183 Defining_Identifier (Decl));
12185 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
12189 Next_Formal (Formal);
12191 end Set_Actual_Subtypes;
12193 ---------------------
12194 -- Set_Formal_Mode --
12195 ---------------------
12197 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
12198 Spec : constant Node_Id := Parent (Formal_Id);
12199 Id : constant Entity_Id := Scope (Formal_Id);
12202 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
12203 -- since we ensure that corresponding actuals are always valid at the
12204 -- point of the call.
12206 if Out_Present (Spec) then
12207 if Ekind_In (Id, E_Entry, E_Entry_Family)
12208 or else Is_Subprogram_Or_Generic_Subprogram (Id)
12210 Set_Has_Out_Or_In_Out_Parameter (Id, True);
12213 if Ekind_In (Id, E_Function, E_Generic_Function) then
12215 -- [IN] OUT parameters allowed for functions in Ada 2012
12217 if Ada_Version >= Ada_2012 then
12219 -- Even in Ada 2012 operators can only have IN parameters
12221 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
12222 Error_Msg_N ("operators can only have IN parameters", Spec);
12225 if In_Present (Spec) then
12226 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12228 Set_Ekind (Formal_Id, E_Out_Parameter);
12231 -- But not in earlier versions of Ada
12234 Error_Msg_N ("functions can only have IN parameters", Spec);
12235 Set_Ekind (Formal_Id, E_In_Parameter);
12238 elsif In_Present (Spec) then
12239 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12242 Set_Ekind (Formal_Id, E_Out_Parameter);
12243 Set_Never_Set_In_Source (Formal_Id, True);
12244 Set_Is_True_Constant (Formal_Id, False);
12245 Set_Current_Value (Formal_Id, Empty);
12249 Set_Ekind (Formal_Id, E_In_Parameter);
12252 -- Set Is_Known_Non_Null for access parameters since the language
12253 -- guarantees that access parameters are always non-null. We also set
12254 -- Can_Never_Be_Null, since there is no way to change the value.
12256 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
12258 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
12259 -- null; In Ada 2005, only if then null_exclusion is explicit.
12261 if Ada_Version < Ada_2005
12262 or else Can_Never_Be_Null (Etype (Formal_Id))
12264 Set_Is_Known_Non_Null (Formal_Id);
12265 Set_Can_Never_Be_Null (Formal_Id);
12268 -- Ada 2005 (AI-231): Null-exclusion access subtype
12270 elsif Is_Access_Type (Etype (Formal_Id))
12271 and then Can_Never_Be_Null (Etype (Formal_Id))
12273 Set_Is_Known_Non_Null (Formal_Id);
12275 -- We can also set Can_Never_Be_Null (thus preventing some junk
12276 -- access checks) for the case of an IN parameter, which cannot
12277 -- be changed, or for an IN OUT parameter, which can be changed but
12278 -- not to a null value. But for an OUT parameter, the initial value
12279 -- passed in can be null, so we can't set this flag in that case.
12281 if Ekind (Formal_Id) /= E_Out_Parameter then
12282 Set_Can_Never_Be_Null (Formal_Id);
12286 Set_Mechanism (Formal_Id, Default_Mechanism);
12287 Set_Formal_Validity (Formal_Id);
12288 end Set_Formal_Mode;
12290 -------------------------
12291 -- Set_Formal_Validity --
12292 -------------------------
12294 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12296 -- If no validity checking, then we cannot assume anything about the
12297 -- validity of parameters, since we do not know there is any checking
12298 -- of the validity on the call side.
12300 if not Validity_Checks_On then
12303 -- If validity checking for parameters is enabled, this means we are
12304 -- not supposed to make any assumptions about argument values.
12306 elsif Validity_Check_Parameters then
12309 -- If we are checking in parameters, we will assume that the caller is
12310 -- also checking parameters, so we can assume the parameter is valid.
12312 elsif Ekind (Formal_Id) = E_In_Parameter
12313 and then Validity_Check_In_Params
12315 Set_Is_Known_Valid (Formal_Id, True);
12317 -- Similar treatment for IN OUT parameters
12319 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12320 and then Validity_Check_In_Out_Params
12322 Set_Is_Known_Valid (Formal_Id, True);
12324 end Set_Formal_Validity;
12326 ------------------------
12327 -- Subtype_Conformant --
12328 ------------------------
12330 function Subtype_Conformant
12331 (New_Id : Entity_Id;
12332 Old_Id : Entity_Id;
12333 Skip_Controlling_Formals : Boolean := False) return Boolean
12337 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12338 Skip_Controlling_Formals => Skip_Controlling_Formals);
12340 end Subtype_Conformant;
12342 ---------------------
12343 -- Type_Conformant --
12344 ---------------------
12346 function Type_Conformant
12347 (New_Id : Entity_Id;
12348 Old_Id : Entity_Id;
12349 Skip_Controlling_Formals : Boolean := False) return Boolean
12353 May_Hide_Profile := False;
12355 (New_Id, Old_Id, Type_Conformant, False, Result,
12356 Skip_Controlling_Formals => Skip_Controlling_Formals);
12358 end Type_Conformant;
12360 -------------------------------
12361 -- Valid_Operator_Definition --
12362 -------------------------------
12364 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12367 Id : constant Name_Id := Chars (Designator);
12371 F := First_Formal (Designator);
12372 while Present (F) loop
12375 if Present (Default_Value (F)) then
12377 ("default values not allowed for operator parameters",
12380 -- For function instantiations that are operators, we must check
12381 -- separately that the corresponding generic only has in-parameters.
12382 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12383 -- an error could not arise in earlier versions of the language.
12385 elsif Ekind (F) /= E_In_Parameter then
12386 Error_Msg_N ("operators can only have IN parameters", F);
12392 -- Verify that user-defined operators have proper number of arguments
12393 -- First case of operators which can only be unary
12395 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12398 -- Case of operators which can be unary or binary
12400 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12401 N_OK := (N in 1 .. 2);
12403 -- All other operators can only be binary
12411 ("incorrect number of arguments for operator", Designator);
12415 and then Base_Type (Etype (Designator)) = Standard_Boolean
12416 and then not Is_Intrinsic_Subprogram (Designator)
12419 ("explicit definition of inequality not allowed", Designator);
12421 end Valid_Operator_Definition;