1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id);
210 -- Preanalysis of default expressions of subprogram formals. N is the
211 -- expression to be analyzed and T is the expected type.
213 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
214 -- Formal_Id is an formal parameter entity. This procedure deals with
215 -- setting the proper validity status for this entity, which depends on
216 -- the kind of parameter and the validity checking mode.
218 ---------------------------------------------
219 -- Analyze_Abstract_Subprogram_Declaration --
220 ---------------------------------------------
222 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
223 Scop : constant Entity_Id := Current_Scope;
224 Subp_Id : constant Entity_Id :=
225 Analyze_Subprogram_Specification (Specification (N));
228 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
230 Generate_Definition (Subp_Id);
232 -- Set the SPARK mode from the current context (may be overwritten later
233 -- with explicit pragma).
235 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
236 Set_SPARK_Pragma_Inherited (Subp_Id);
238 -- Preserve relevant elaboration-related attributes of the context which
239 -- are no longer available or very expensive to recompute once analysis,
240 -- resolution, and expansion are over.
242 Mark_Elaboration_Attributes
247 Set_Is_Abstract_Subprogram (Subp_Id);
248 New_Overloaded_Entity (Subp_Id);
249 Check_Delayed_Subprogram (Subp_Id);
251 Set_Categorization_From_Scope (Subp_Id, Scop);
253 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
254 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
256 -- Issue a warning if the abstract subprogram is neither a dispatching
257 -- operation nor an operation that overrides an inherited subprogram or
258 -- predefined operator, since this most likely indicates a mistake.
260 elsif Warn_On_Redundant_Constructs
261 and then not Is_Dispatching_Operation (Subp_Id)
262 and then not Present (Overridden_Operation (Subp_Id))
263 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
264 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
267 ("abstract subprogram is not dispatching or overriding?r?", N);
270 Generate_Reference_To_Formals (Subp_Id);
271 Check_Eliminated (Subp_Id);
273 if Has_Aspects (N) then
274 Analyze_Aspect_Specifications (N, Subp_Id);
276 end Analyze_Abstract_Subprogram_Declaration;
278 ---------------------------------
279 -- Analyze_Expression_Function --
280 ---------------------------------
282 procedure Analyze_Expression_Function (N : Node_Id) is
283 Expr : constant Node_Id := Expression (N);
284 Loc : constant Source_Ptr := Sloc (N);
285 LocX : constant Source_Ptr := Sloc (Expr);
286 Spec : constant Node_Id := Specification (N);
296 Def_Id : Entity_Id := Empty;
298 -- If the expression is a completion, Prev is the entity whose
299 -- declaration is completed. Def_Id is needed to analyze the spec.
301 -- Start of processing for Analyze_Expression_Function
304 -- This is one of the occasions on which we transform the tree during
305 -- semantic analysis. If this is a completion, transform the expression
306 -- function into an equivalent subprogram body, and analyze it.
308 -- Expression functions are inlined unconditionally. The back-end will
309 -- determine whether this is possible.
311 Inline_Processing_Required := True;
313 -- Create a specification for the generated body. This must be done
314 -- prior to the analysis of the initial declaration.
316 New_Spec := Copy_Subprogram_Spec (Spec);
317 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
319 -- If there are previous overloadable entities with the same name,
320 -- check whether any of them is completed by the expression function.
321 -- In a generic context a formal subprogram has no completion.
324 and then Is_Overloadable (Prev)
325 and then not Is_Formal_Subprogram (Prev)
327 Def_Id := Analyze_Subprogram_Specification (Spec);
328 Prev := Find_Corresponding_Spec (N);
330 -- The previous entity may be an expression function as well, in
331 -- which case the redeclaration is illegal.
334 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
335 N_Expression_Function
337 Error_Msg_Sloc := Sloc (Prev);
338 Error_Msg_N ("& conflicts with declaration#", Def_Id);
343 Ret := Make_Simple_Return_Statement (LocX, Expr);
346 Make_Subprogram_Body (Loc,
347 Specification => New_Spec,
348 Declarations => Empty_List,
349 Handled_Statement_Sequence =>
350 Make_Handled_Sequence_Of_Statements (LocX,
351 Statements => New_List (Ret)));
352 Set_Was_Expression_Function (New_Body);
354 -- If the expression completes a generic subprogram, we must create a
355 -- separate node for the body, because at instantiation the original
356 -- node of the generic copy must be a generic subprogram body, and
357 -- cannot be a expression function. Otherwise we just rewrite the
358 -- expression with the non-generic body.
360 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
361 Insert_After (N, New_Body);
363 -- Propagate any aspects or pragmas that apply to the expression
364 -- function to the proper body when the expression function acts
367 if Has_Aspects (N) then
368 Move_Aspects (N, To => New_Body);
371 Relocate_Pragmas_To_Body (New_Body);
373 Rewrite (N, Make_Null_Statement (Loc));
374 Set_Has_Completion (Prev, False);
377 Set_Is_Inlined (Prev);
379 -- If the expression function is a completion, the previous declaration
380 -- must come from source. We know already that it appears in the current
381 -- scope. The entity itself may be internally created if within a body
385 and then Is_Overloadable (Prev)
386 and then not Is_Formal_Subprogram (Prev)
387 and then Comes_From_Source (Parent (Prev))
389 Set_Has_Completion (Prev, False);
390 Set_Is_Inlined (Prev);
392 -- AI12-0103: Expression functions that are a completion freeze their
393 -- expression but don't freeze anything else (unlike regular bodies).
395 -- Note that we cannot defer this freezing to the analysis of the
396 -- expression itself, because a freeze node might appear in a nested
397 -- scope, leading to an elaboration order issue in gigi.
398 -- As elsewhere, we do not emit freeze nodes within a generic unit.
400 if not Inside_A_Generic then
403 Typ => Etype (Def_Id),
408 -- For navigation purposes, indicate that the function is a body
410 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
411 Rewrite (N, New_Body);
413 -- Remove any existing aspects from the original node because the act
414 -- of rewriting causes the list to be shared between the two nodes.
416 Orig_N := Original_Node (N);
417 Remove_Aspects (Orig_N);
419 -- Propagate any pragmas that apply to expression function to the
420 -- proper body when the expression function acts as a completion.
421 -- Aspects are automatically transfered because of node rewriting.
423 Relocate_Pragmas_To_Body (N);
426 -- Once the aspects of the generated body have been analyzed, create
427 -- a copy for ASIS purposes and associate it with the original node.
429 if Has_Aspects (N) then
430 Set_Aspect_Specifications (Orig_N,
431 New_Copy_List_Tree (Aspect_Specifications (N)));
434 -- Prev is the previous entity with the same name, but it is can
435 -- be an unrelated spec that is not completed by the expression
436 -- function. In that case the relevant entity is the one in the body.
437 -- Not clear that the backend can inline it in this case ???
439 if Has_Completion (Prev) then
441 -- The formals of the expression function are body formals,
442 -- and do not appear in the ali file, which will only contain
443 -- references to the formals of the original subprogram spec.
450 F1 := First_Formal (Def_Id);
451 F2 := First_Formal (Prev);
453 while Present (F1) loop
454 Set_Spec_Entity (F1, F2);
461 Set_Is_Inlined (Defining_Entity (New_Body));
464 -- If this is not a completion, create both a declaration and a body, so
465 -- that the expression can be inlined whenever possible.
468 -- An expression function that is not a completion is not a
469 -- subprogram declaration, and thus cannot appear in a protected
472 if Nkind (Parent (N)) = N_Protected_Definition then
474 ("an expression function is not a legal protected operation", N);
477 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
479 -- Remove any existing aspects from the original node because the act
480 -- of rewriting causes the list to be shared between the two nodes.
482 Orig_N := Original_Node (N);
483 Remove_Aspects (Orig_N);
487 -- Once the aspects of the generated spec have been analyzed, create
488 -- a copy for ASIS purposes and associate it with the original node.
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_Aggregate_Accessibility (Aggr : Node_Id);
698 -- Apply legality rule of 6.5 (5.8) 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_Aggregate_Accessibility --
707 -----------------------------------
709 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
710 Typ : constant Entity_Id := Etype (Aggr);
717 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
718 Discr := First_Discriminant (Typ);
719 Assoc := First (Component_Associations (Aggr));
720 while Present (Discr) loop
721 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
722 Expr := Expression (Assoc);
724 if Nkind (Expr) = N_Attribute_Reference
725 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
727 Obj := Prefix (Expr);
728 while Nkind_In (Obj, N_Indexed_Component,
729 N_Selected_Component)
734 -- Do not check aliased formals or function calls. A
735 -- run-time check may still be needed ???
737 if Is_Entity_Name (Obj)
738 and then Comes_From_Source (Obj)
740 if Is_Formal (Entity (Obj))
741 and then Is_Aliased (Entity (Obj))
745 elsif Object_Access_Level (Obj) >
746 Scope_Depth (Scope (Scope_Id))
749 ("access discriminant in return aggregate would "
750 & "be a dangling reference", Obj);
756 Next_Discriminant (Discr);
759 end Check_Aggregate_Accessibility;
761 -------------------------------------
762 -- Check_Return_Subtype_Indication --
763 -------------------------------------
765 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
766 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
768 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
769 -- Subtype given in the extended return statement (must match R_Type)
771 Subtype_Ind : constant Node_Id :=
772 Object_Definition (Original_Node (Obj_Decl));
774 procedure Error_No_Match (N : Node_Id);
775 -- Output error messages for case where types do not statically
776 -- match. N is the location for the messages.
782 procedure Error_No_Match (N : Node_Id) is
785 ("subtype must statically match function result subtype", N);
787 if not Predicates_Match (R_Stm_Type, R_Type) then
788 Error_Msg_Node_2 := R_Type;
790 ("\predicate of& does not match predicate of&",
795 -- Start of processing for Check_Return_Subtype_Indication
798 -- First, avoid cascaded errors
800 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
804 -- "return access T" case; check that the return statement also has
805 -- "access T", and that the subtypes statically match:
806 -- if this is an access to subprogram the signatures must match.
808 if Is_Anonymous_Access_Type (R_Type) then
809 if Is_Anonymous_Access_Type (R_Stm_Type) then
810 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
812 if Base_Type (Designated_Type (R_Stm_Type)) /=
813 Base_Type (Designated_Type (R_Type))
814 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
816 Error_No_Match (Subtype_Mark (Subtype_Ind));
820 -- For two anonymous access to subprogram types, the types
821 -- themselves must be type conformant.
823 if not Conforming_Types
824 (R_Stm_Type, R_Type, Fully_Conformant)
826 Error_No_Match (Subtype_Ind);
831 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
834 -- If the return object is of an anonymous access type, then report
835 -- an error if the function's result type is not also anonymous.
837 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
838 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
840 ("anonymous access not allowed for function with named access "
841 & "result", Subtype_Ind);
843 -- Subtype indication case: check that the return object's type is
844 -- covered by the result type, and that the subtypes statically match
845 -- when the result subtype is constrained. Also handle record types
846 -- with unknown discriminants for which we have built the underlying
847 -- record view. Coverage is needed to allow specific-type return
848 -- objects when the result type is class-wide (see AI05-32).
850 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
851 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
855 Underlying_Record_View (Base_Type (R_Stm_Type))))
857 -- A null exclusion may be present on the return type, on the
858 -- function specification, on the object declaration or on the
861 if Is_Access_Type (R_Type)
863 (Can_Never_Be_Null (R_Type)
864 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
865 Can_Never_Be_Null (R_Stm_Type)
867 Error_No_Match (Subtype_Ind);
870 -- AI05-103: for elementary types, subtypes must statically match
872 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
873 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
874 Error_No_Match (Subtype_Ind);
878 -- All remaining cases are illegal
880 -- Note: previous versions of this subprogram allowed the return
881 -- value to be the ancestor of the return type if the return type
882 -- was a null extension. This was plainly incorrect.
886 ("wrong type for return_subtype_indication", Subtype_Ind);
888 end Check_Return_Subtype_Indication;
890 ---------------------
891 -- Local Variables --
892 ---------------------
895 Obj_Decl : Node_Id := Empty;
897 -- Start of processing for Analyze_Function_Return
900 Set_Return_Present (Scope_Id);
902 if Nkind (N) = N_Simple_Return_Statement then
903 Expr := Expression (N);
905 -- Guard against a malformed expression. The parser may have tried to
906 -- recover but the node is not analyzable.
908 if Nkind (Expr) = N_Error then
909 Set_Etype (Expr, Any_Type);
910 Expander_Mode_Save_And_Set (False);
914 -- The resolution of a controlled [extension] aggregate associated
915 -- with a return statement creates a temporary which needs to be
916 -- finalized on function exit. Wrap the return statement inside a
917 -- block so that the finalization machinery can detect this case.
918 -- This early expansion is done only when the return statement is
919 -- not part of a handled sequence of statements.
921 if Nkind_In (Expr, N_Aggregate,
922 N_Extension_Aggregate)
923 and then Needs_Finalization (R_Type)
924 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
927 Make_Block_Statement (Loc,
928 Handled_Statement_Sequence =>
929 Make_Handled_Sequence_Of_Statements (Loc,
930 Statements => New_List (Relocate_Node (N)))));
938 -- Ada 2005 (AI-251): If the type of the returned object is
939 -- an access to an interface type then we add an implicit type
940 -- conversion to force the displacement of the "this" pointer to
941 -- reference the secondary dispatch table. We cannot delay the
942 -- generation of this implicit conversion until the expansion
943 -- because in this case the type resolution changes the decoration
944 -- of the expression node to match R_Type; by contrast, if the
945 -- returned object is a class-wide interface type then it is too
946 -- early to generate here the implicit conversion since the return
947 -- statement may be rewritten by the expander into an extended
948 -- return statement whose expansion takes care of adding the
949 -- implicit type conversion to displace the pointer to the object.
952 and then Serious_Errors_Detected = 0
953 and then Is_Access_Type (R_Type)
954 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
955 and then Is_Interface (Designated_Type (R_Type))
956 and then Is_Progenitor (Designated_Type (R_Type),
957 Designated_Type (Etype (Expr)))
959 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
963 Resolve (Expr, R_Type);
964 Check_Limited_Return (N, Expr, R_Type);
966 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
967 Check_Aggregate_Accessibility (Expr);
971 -- RETURN only allowed in SPARK as the last statement in function
973 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
975 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
976 or else Present (Next (N)))
978 Check_SPARK_05_Restriction
979 ("RETURN should be the last statement in function", N);
983 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
984 Obj_Decl := Last (Return_Object_Declarations (N));
986 -- Analyze parts specific to extended_return_statement:
989 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
990 HSS : constant Node_Id := Handled_Statement_Sequence (N);
993 Expr := Expression (Obj_Decl);
995 -- Note: The check for OK_For_Limited_Init will happen in
996 -- Analyze_Object_Declaration; we treat it as a normal
997 -- object declaration.
999 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1002 Check_Return_Subtype_Indication (Obj_Decl);
1004 if Present (HSS) then
1007 if Present (Exception_Handlers (HSS)) then
1009 -- ???Has_Nested_Block_With_Handler needs to be set.
1010 -- Probably by creating an actual N_Block_Statement.
1011 -- Probably in Expand.
1017 -- Mark the return object as referenced, since the return is an
1018 -- implicit reference of the object.
1020 Set_Referenced (Defining_Identifier (Obj_Decl));
1022 Check_References (Stm_Entity);
1024 -- Check RM 6.5 (5.9/3)
1027 if Ada_Version < Ada_2012 then
1029 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1030 -- Can it really happen (extended return???)
1033 ("aliased only allowed for limited return objects "
1034 & "in Ada 2012??", N);
1036 elsif not Is_Limited_View (R_Type) then
1038 ("aliased only allowed for limited return objects", N);
1044 -- Case of Expr present
1046 if Present (Expr) then
1048 -- Defend against previous errors
1050 if Nkind (Expr) = N_Empty
1051 or else No (Etype (Expr))
1056 -- Apply constraint check. Note that this is done before the implicit
1057 -- conversion of the expression done for anonymous access types to
1058 -- ensure correct generation of the null-excluding check associated
1059 -- with null-excluding expressions found in return statements.
1061 Apply_Constraint_Check (Expr, R_Type);
1063 -- The return value is converted to the return type of the function,
1064 -- which implies a predicate check if the return type is predicated.
1065 -- We do not apply the check to a case expression because it will
1066 -- be expanded into a series of return statements, each of which
1067 -- will receive a predicate check.
1069 if Nkind (Expr) /= N_Case_Expression then
1070 Apply_Predicate_Check (Expr, R_Type);
1073 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1074 -- type, apply an implicit conversion of the expression to that type
1075 -- to force appropriate static and run-time accessibility checks.
1077 if Ada_Version >= Ada_2005
1078 and then Ekind (R_Type) = E_Anonymous_Access_Type
1080 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1081 Analyze_And_Resolve (Expr, R_Type);
1083 -- If this is a local anonymous access to subprogram, the
1084 -- accessibility check can be applied statically. The return is
1085 -- illegal if the access type of the return expression is declared
1086 -- inside of the subprogram (except if it is the subtype indication
1087 -- of an extended return statement).
1089 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1090 if not Comes_From_Source (Current_Scope)
1091 or else Ekind (Current_Scope) = E_Return_Statement
1096 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1098 Error_Msg_N ("cannot return local access to subprogram", N);
1101 -- The expression cannot be of a formal incomplete type
1103 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1104 and then Is_Generic_Type (Etype (Expr))
1107 ("cannot return expression of a formal incomplete type", N);
1110 -- If the result type is class-wide, then check that the return
1111 -- expression's type is not declared at a deeper level than the
1112 -- function (RM05-6.5(5.6/2)).
1114 if Ada_Version >= Ada_2005
1115 and then Is_Class_Wide_Type (R_Type)
1117 if Type_Access_Level (Etype (Expr)) >
1118 Subprogram_Access_Level (Scope_Id)
1121 ("level of return expression type is deeper than "
1122 & "class-wide function!", Expr);
1126 -- Check incorrect use of dynamically tagged expression
1128 if Is_Tagged_Type (R_Type) then
1129 Check_Dynamically_Tagged_Expression
1135 -- ??? A real run-time accessibility check is needed in cases
1136 -- involving dereferences of access parameters. For now we just
1137 -- check the static cases.
1139 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1140 and then Is_Limited_View (Etype (Scope_Id))
1141 and then Object_Access_Level (Expr) >
1142 Subprogram_Access_Level (Scope_Id)
1144 -- Suppress the message in a generic, where the rewriting
1147 if Inside_A_Generic then
1152 Make_Raise_Program_Error (Loc,
1153 Reason => PE_Accessibility_Check_Failed));
1156 Error_Msg_Warn := SPARK_Mode /= On;
1157 Error_Msg_N ("cannot return a local value by reference<<", N);
1158 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1162 if Known_Null (Expr)
1163 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1164 and then Null_Exclusion_Present (Parent (Scope_Id))
1166 Apply_Compile_Time_Constraint_Error
1168 Msg => "(Ada 2005) null not allowed for "
1169 & "null-excluding return??",
1170 Reason => CE_Null_Not_Allowed);
1173 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1174 -- has no initializing expression.
1176 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1177 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1178 Subprogram_Access_Level (Scope_Id)
1181 ("level of return expression type is deeper than "
1182 & "class-wide function!", Obj_Decl);
1185 end Analyze_Function_Return;
1187 -------------------------------------
1188 -- Analyze_Generic_Subprogram_Body --
1189 -------------------------------------
1191 procedure Analyze_Generic_Subprogram_Body
1195 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1196 Kind : constant Entity_Kind := Ekind (Gen_Id);
1197 Body_Id : Entity_Id;
1202 -- Copy body and disable expansion while analyzing the generic For a
1203 -- stub, do not copy the stub (which would load the proper body), this
1204 -- will be done when the proper body is analyzed.
1206 if Nkind (N) /= N_Subprogram_Body_Stub then
1207 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1210 -- Once the contents of the generic copy and the template are
1211 -- swapped, do the same for their respective aspect specifications.
1213 Exchange_Aspects (N, New_N);
1215 -- Collect all contract-related source pragmas found within the
1216 -- template and attach them to the contract of the subprogram body.
1217 -- This contract is used in the capture of global references within
1220 Create_Generic_Contract (N);
1225 Spec := Specification (N);
1227 -- Within the body of the generic, the subprogram is callable, and
1228 -- behaves like the corresponding non-generic unit.
1230 Body_Id := Defining_Entity (Spec);
1232 if Kind = E_Generic_Procedure
1233 and then Nkind (Spec) /= N_Procedure_Specification
1235 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1238 elsif Kind = E_Generic_Function
1239 and then Nkind (Spec) /= N_Function_Specification
1241 Error_Msg_N ("invalid body for generic function ", Body_Id);
1245 Set_Corresponding_Body (Gen_Decl, Body_Id);
1247 if Has_Completion (Gen_Id)
1248 and then Nkind (Parent (N)) /= N_Subunit
1250 Error_Msg_N ("duplicate generic body", N);
1253 Set_Has_Completion (Gen_Id);
1256 if Nkind (N) = N_Subprogram_Body_Stub then
1257 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1259 Set_Corresponding_Spec (N, Gen_Id);
1262 if Nkind (Parent (N)) = N_Compilation_Unit then
1263 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1266 -- Make generic parameters immediately visible in the body. They are
1267 -- needed to process the formals declarations. Then make the formals
1268 -- visible in a separate step.
1270 Push_Scope (Gen_Id);
1274 First_Ent : Entity_Id;
1277 First_Ent := First_Entity (Gen_Id);
1280 while Present (E) and then not Is_Formal (E) loop
1285 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1287 -- Now generic formals are visible, and the specification can be
1288 -- analyzed, for subsequent conformance check.
1290 Body_Id := Analyze_Subprogram_Specification (Spec);
1292 -- Make formal parameters visible
1296 -- E is the first formal parameter, we loop through the formals
1297 -- installing them so that they will be visible.
1299 Set_First_Entity (Gen_Id, E);
1300 while Present (E) loop
1306 -- Visible generic entity is callable within its own body
1308 Set_Ekind (Gen_Id, Ekind (Body_Id));
1309 Set_Ekind (Body_Id, E_Subprogram_Body);
1310 Set_Convention (Body_Id, Convention (Gen_Id));
1311 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1312 Set_Scope (Body_Id, Scope (Gen_Id));
1314 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1316 if Nkind (N) = N_Subprogram_Body_Stub then
1318 -- No body to analyze, so restore state of generic unit
1320 Set_Ekind (Gen_Id, Kind);
1321 Set_Ekind (Body_Id, Kind);
1323 if Present (First_Ent) then
1324 Set_First_Entity (Gen_Id, First_Ent);
1331 -- If this is a compilation unit, it must be made visible explicitly,
1332 -- because the compilation of the declaration, unlike other library
1333 -- unit declarations, does not. If it is not a unit, the following
1334 -- is redundant but harmless.
1336 Set_Is_Immediately_Visible (Gen_Id);
1337 Reference_Body_Formals (Gen_Id, Body_Id);
1339 if Is_Child_Unit (Gen_Id) then
1340 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1343 Set_Actual_Subtypes (N, Current_Scope);
1345 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1346 Set_SPARK_Pragma_Inherited (Body_Id);
1348 -- Analyze any aspect specifications that appear on the generic
1351 if Has_Aspects (N) then
1352 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1355 Analyze_Declarations (Declarations (N));
1358 -- Process the contract of the subprogram body after all declarations
1359 -- have been analyzed. This ensures that any contract-related pragmas
1360 -- are available through the N_Contract node of the body.
1362 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1364 Analyze (Handled_Statement_Sequence (N));
1365 Save_Global_References (Original_Node (N));
1367 -- Prior to exiting the scope, include generic formals again (if any
1368 -- are present) in the set of local entities.
1370 if Present (First_Ent) then
1371 Set_First_Entity (Gen_Id, First_Ent);
1374 Check_References (Gen_Id);
1377 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1378 Update_Use_Clause_Chain;
1379 Validate_Categorization_Dependency (N, Gen_Id);
1381 Check_Subprogram_Order (N);
1383 -- Outside of its body, unit is generic again
1385 Set_Ekind (Gen_Id, Kind);
1386 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1389 Style.Check_Identifier (Body_Id, Gen_Id);
1393 end Analyze_Generic_Subprogram_Body;
1395 ----------------------------
1396 -- Analyze_Null_Procedure --
1397 ----------------------------
1399 procedure Analyze_Null_Procedure
1401 Is_Completion : out Boolean)
1403 Loc : constant Source_Ptr := Sloc (N);
1404 Spec : constant Node_Id := Specification (N);
1405 Designator : Entity_Id;
1407 Null_Body : Node_Id := Empty;
1408 Null_Stmt : Node_Id := Null_Statement (Spec);
1412 -- Capture the profile of the null procedure before analysis, for
1413 -- expansion at the freeze point and at each point of call. The body is
1414 -- used if the procedure has preconditions, or if it is a completion. In
1415 -- the first case the body is analyzed at the freeze point, in the other
1416 -- it replaces the null procedure declaration.
1418 -- For a null procedure that comes from source, a NULL statement is
1419 -- provided by the parser, which carries the source location of the
1420 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1421 -- from expansion, create one now.
1423 if No (Null_Stmt) then
1424 Null_Stmt := Make_Null_Statement (Loc);
1428 Make_Subprogram_Body (Loc,
1429 Specification => New_Copy_Tree (Spec),
1430 Declarations => New_List,
1431 Handled_Statement_Sequence =>
1432 Make_Handled_Sequence_Of_Statements (Loc,
1433 Statements => New_List (Null_Stmt)));
1435 -- Create new entities for body and formals
1437 Set_Defining_Unit_Name (Specification (Null_Body),
1438 Make_Defining_Identifier
1439 (Sloc (Defining_Entity (N)),
1440 Chars (Defining_Entity (N))));
1442 Form := First (Parameter_Specifications (Specification (Null_Body)));
1443 while Present (Form) loop
1444 Set_Defining_Identifier (Form,
1445 Make_Defining_Identifier
1446 (Sloc (Defining_Identifier (Form)),
1447 Chars (Defining_Identifier (Form))));
1451 -- Determine whether the null procedure may be a completion of a generic
1452 -- suprogram, in which case we use the new null body as the completion
1453 -- and set minimal semantic information on the original declaration,
1454 -- which is rewritten as a null statement.
1456 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1458 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1459 Insert_Before (N, Null_Body);
1460 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1462 Rewrite (N, Make_Null_Statement (Loc));
1463 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1464 Is_Completion := True;
1468 -- Resolve the types of the formals now, because the freeze point may
1469 -- appear in a different context, e.g. an instantiation.
1471 Form := First (Parameter_Specifications (Specification (Null_Body)));
1472 while Present (Form) loop
1473 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1474 Find_Type (Parameter_Type (Form));
1476 elsif No (Access_To_Subprogram_Definition
1477 (Parameter_Type (Form)))
1479 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1481 -- The case of a null procedure with a formal that is an
1482 -- access-to-subprogram type, and that is used as an actual
1483 -- in an instantiation is left to the enthusiastic reader.
1493 -- If there are previous overloadable entities with the same name, check
1494 -- whether any of them is completed by the null procedure.
1496 if Present (Prev) and then Is_Overloadable (Prev) then
1497 Designator := Analyze_Subprogram_Specification (Spec);
1498 Prev := Find_Corresponding_Spec (N);
1501 if No (Prev) or else not Comes_From_Source (Prev) then
1502 Designator := Analyze_Subprogram_Specification (Spec);
1503 Set_Has_Completion (Designator);
1505 -- Signal to caller that this is a procedure declaration
1507 Is_Completion := False;
1509 -- Null procedures are always inlined, but generic formal subprograms
1510 -- which appear as such in the internal instance of formal packages,
1511 -- need no completion and are not marked Inline.
1514 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1516 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1517 Set_Body_To_Inline (N, Null_Body);
1518 Set_Is_Inlined (Designator);
1522 -- The null procedure is a completion. We unconditionally rewrite
1523 -- this as a null body (even if expansion is not active), because
1524 -- there are various error checks that are applied on this body
1525 -- when it is analyzed (e.g. correct aspect placement).
1527 if Has_Completion (Prev) then
1528 Error_Msg_Sloc := Sloc (Prev);
1529 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1532 Check_Previous_Null_Procedure (N, Prev);
1534 Is_Completion := True;
1535 Rewrite (N, Null_Body);
1538 end Analyze_Null_Procedure;
1540 -----------------------------
1541 -- Analyze_Operator_Symbol --
1542 -----------------------------
1544 -- An operator symbol such as "+" or "and" may appear in context where the
1545 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1546 -- is just a string, as in (conjunction = "or"). In these cases the parser
1547 -- generates this node, and the semantics does the disambiguation. Other
1548 -- such case are actuals in an instantiation, the generic unit in an
1549 -- instantiation, and pragma arguments.
1551 procedure Analyze_Operator_Symbol (N : Node_Id) is
1552 Par : constant Node_Id := Parent (N);
1555 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1556 or else Nkind (Par) = N_Function_Instantiation
1557 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1558 or else (Nkind (Par) = N_Pragma_Argument_Association
1559 and then not Is_Pragma_String_Literal (Par))
1560 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1561 or else (Nkind (Par) = N_Attribute_Reference
1562 and then Attribute_Name (Par) /= Name_Value)
1564 Find_Direct_Name (N);
1567 Change_Operator_Symbol_To_String_Literal (N);
1570 end Analyze_Operator_Symbol;
1572 -----------------------------------
1573 -- Analyze_Parameter_Association --
1574 -----------------------------------
1576 procedure Analyze_Parameter_Association (N : Node_Id) is
1578 Analyze (Explicit_Actual_Parameter (N));
1579 end Analyze_Parameter_Association;
1581 ----------------------------
1582 -- Analyze_Procedure_Call --
1583 ----------------------------
1585 -- WARNING: This routine manages Ghost regions. Return statements must be
1586 -- replaced by gotos which jump to the end of the routine and restore the
1589 procedure Analyze_Procedure_Call (N : Node_Id) is
1590 procedure Analyze_Call_And_Resolve;
1591 -- Do Analyze and Resolve calls for procedure call. At the end, check
1592 -- for illegal order dependence.
1593 -- ??? where is the check for illegal order dependencies?
1595 ------------------------------
1596 -- Analyze_Call_And_Resolve --
1597 ------------------------------
1599 procedure Analyze_Call_And_Resolve is
1601 if Nkind (N) = N_Procedure_Call_Statement then
1603 Resolve (N, Standard_Void_Type);
1607 end Analyze_Call_And_Resolve;
1611 Actuals : constant List_Id := Parameter_Associations (N);
1612 Loc : constant Source_Ptr := Sloc (N);
1613 P : constant Node_Id := Name (N);
1615 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1616 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1617 -- Save the Ghost-related attributes to restore on exit
1622 -- Start of processing for Analyze_Procedure_Call
1625 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1626 -- a procedure call or an entry call. The prefix may denote an access
1627 -- to subprogram type, in which case an implicit dereference applies.
1628 -- If the prefix is an indexed component (without implicit dereference)
1629 -- then the construct denotes a call to a member of an entire family.
1630 -- If the prefix is a simple name, it may still denote a call to a
1631 -- parameterless member of an entry family. Resolution of these various
1632 -- interpretations is delicate.
1634 -- Do not analyze machine code statements to avoid rejecting them in
1637 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1638 Set_Etype (P, Standard_Void_Type);
1643 -- If this is a call of the form Obj.Op, the call may have been analyzed
1644 -- and possibly rewritten into a block, in which case we are done.
1646 if Analyzed (N) then
1649 -- If there is an error analyzing the name (which may have been
1650 -- rewritten if the original call was in prefix notation) then error
1651 -- has been emitted already, mark node and return.
1653 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1654 Set_Etype (N, Any_Type);
1658 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1659 -- Set the mode now to ensure that any nodes generated during analysis
1660 -- and expansion are properly marked as Ghost.
1662 Mark_And_Set_Ghost_Procedure_Call (N);
1664 -- Otherwise analyze the parameters
1666 if Present (Actuals) then
1667 Actual := First (Actuals);
1669 while Present (Actual) loop
1671 Check_Parameterless_Call (Actual);
1676 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1678 if Nkind (P) = N_Attribute_Reference
1679 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1681 Name_Elab_Subp_Body)
1683 if Present (Actuals) then
1685 ("no parameters allowed for this call", First (Actuals));
1689 Set_Etype (N, Standard_Void_Type);
1692 elsif Is_Entity_Name (P)
1693 and then Is_Record_Type (Etype (Entity (P)))
1694 and then Remote_AST_I_Dereference (P)
1698 elsif Is_Entity_Name (P)
1699 and then Ekind (Entity (P)) /= E_Entry_Family
1701 if Is_Access_Type (Etype (P))
1702 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1703 and then No (Actuals)
1704 and then Comes_From_Source (N)
1706 Error_Msg_N ("missing explicit dereference in call", N);
1709 Analyze_Call_And_Resolve;
1711 -- If the prefix is the simple name of an entry family, this is a
1712 -- parameterless call from within the task body itself.
1714 elsif Is_Entity_Name (P)
1715 and then Nkind (P) = N_Identifier
1716 and then Ekind (Entity (P)) = E_Entry_Family
1717 and then Present (Actuals)
1718 and then No (Next (First (Actuals)))
1720 -- Can be call to parameterless entry family. What appears to be the
1721 -- sole argument is in fact the entry index. Rewrite prefix of node
1722 -- accordingly. Source representation is unchanged by this
1726 Make_Indexed_Component (Loc,
1728 Make_Selected_Component (Loc,
1729 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1730 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1731 Expressions => Actuals);
1732 Set_Name (N, New_N);
1733 Set_Etype (New_N, Standard_Void_Type);
1734 Set_Parameter_Associations (N, No_List);
1735 Analyze_Call_And_Resolve;
1737 elsif Nkind (P) = N_Explicit_Dereference then
1738 if Ekind (Etype (P)) = E_Subprogram_Type then
1739 Analyze_Call_And_Resolve;
1741 Error_Msg_N ("expect access to procedure in call", P);
1744 -- The name can be a selected component or an indexed component that
1745 -- yields an access to subprogram. Such a prefix is legal if the call
1746 -- has parameter associations.
1748 elsif Is_Access_Type (Etype (P))
1749 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1751 if Present (Actuals) then
1752 Analyze_Call_And_Resolve;
1754 Error_Msg_N ("missing explicit dereference in call ", N);
1757 -- If not an access to subprogram, then the prefix must resolve to the
1758 -- name of an entry, entry family, or protected operation.
1760 -- For the case of a simple entry call, P is a selected component where
1761 -- the prefix is the task and the selector name is the entry. A call to
1762 -- a protected procedure will have the same syntax. If the protected
1763 -- object contains overloaded operations, the entity may appear as a
1764 -- function, the context will select the operation whose type is Void.
1766 elsif Nkind (P) = N_Selected_Component
1767 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1771 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1772 -- in prefix notation may still be missing its controlling argument,
1773 -- so perform the transformation now.
1775 if SPARK_Mode = On and then In_Inlined_Body then
1777 Subp : constant Entity_Id := Entity (Selector_Name (P));
1778 Typ : constant Entity_Id := Etype (Prefix (P));
1781 if Is_Tagged_Type (Typ)
1782 and then Present (First_Formal (Subp))
1783 and then (Etype (First_Formal (Subp)) = Typ
1785 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1786 and then Try_Object_Operation (P)
1791 Analyze_Call_And_Resolve;
1796 Analyze_Call_And_Resolve;
1799 elsif Nkind (P) = N_Selected_Component
1800 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1801 and then Present (Actuals)
1802 and then No (Next (First (Actuals)))
1804 -- Can be call to parameterless entry family. What appears to be the
1805 -- sole argument is in fact the entry index. Rewrite prefix of node
1806 -- accordingly. Source representation is unchanged by this
1810 Make_Indexed_Component (Loc,
1811 Prefix => New_Copy (P),
1812 Expressions => Actuals);
1813 Set_Name (N, New_N);
1814 Set_Etype (New_N, Standard_Void_Type);
1815 Set_Parameter_Associations (N, No_List);
1816 Analyze_Call_And_Resolve;
1818 -- For the case of a reference to an element of an entry family, P is
1819 -- an indexed component whose prefix is a selected component (task and
1820 -- entry family), and whose index is the entry family index.
1822 elsif Nkind (P) = N_Indexed_Component
1823 and then Nkind (Prefix (P)) = N_Selected_Component
1824 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1826 Analyze_Call_And_Resolve;
1828 -- If the prefix is the name of an entry family, it is a call from
1829 -- within the task body itself.
1831 elsif Nkind (P) = N_Indexed_Component
1832 and then Nkind (Prefix (P)) = N_Identifier
1833 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1836 Make_Selected_Component (Loc,
1838 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1839 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1840 Rewrite (Prefix (P), New_N);
1842 Analyze_Call_And_Resolve;
1844 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1845 -- procedure name, so the construct can only be a qualified expression.
1847 elsif Nkind (P) = N_Qualified_Expression
1848 and then Ada_Version >= Ada_2012
1850 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1853 -- Anything else is an error
1856 Error_Msg_N ("invalid procedure or entry call", N);
1860 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1861 end Analyze_Procedure_Call;
1863 ------------------------------
1864 -- Analyze_Return_Statement --
1865 ------------------------------
1867 procedure Analyze_Return_Statement (N : Node_Id) is
1868 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
1869 N_Simple_Return_Statement));
1871 Returns_Object : constant Boolean :=
1872 Nkind (N) = N_Extended_Return_Statement
1874 (Nkind (N) = N_Simple_Return_Statement
1875 and then Present (Expression (N)));
1876 -- True if we're returning something; that is, "return <expression>;"
1877 -- or "return Result : T [:= ...]". False for "return;". Used for error
1878 -- checking: If Returns_Object is True, N should apply to a function
1879 -- body; otherwise N should apply to a procedure body, entry body,
1880 -- accept statement, or extended return statement.
1882 function Find_What_It_Applies_To return Entity_Id;
1883 -- Find the entity representing the innermost enclosing body, accept
1884 -- statement, or extended return statement. If the result is a callable
1885 -- construct or extended return statement, then this will be the value
1886 -- of the Return_Applies_To attribute. Otherwise, the program is
1887 -- illegal. See RM-6.5(4/2).
1889 -----------------------------
1890 -- Find_What_It_Applies_To --
1891 -----------------------------
1893 function Find_What_It_Applies_To return Entity_Id is
1894 Result : Entity_Id := Empty;
1897 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1898 -- and postconditions.
1900 for J in reverse 0 .. Scope_Stack.Last loop
1901 Result := Scope_Stack.Table (J).Entity;
1902 exit when not Ekind_In (Result, E_Block, E_Loop)
1903 and then Chars (Result) /= Name_uPostconditions;
1906 pragma Assert (Present (Result));
1908 end Find_What_It_Applies_To;
1910 -- Local declarations
1912 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1913 Kind : constant Entity_Kind := Ekind (Scope_Id);
1914 Loc : constant Source_Ptr := Sloc (N);
1915 Stm_Entity : constant Entity_Id :=
1917 (E_Return_Statement, Current_Scope, Loc, 'R');
1919 -- Start of processing for Analyze_Return_Statement
1922 Set_Return_Statement_Entity (N, Stm_Entity);
1924 Set_Etype (Stm_Entity, Standard_Void_Type);
1925 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1927 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1928 -- (4/2): an inner return statement will apply to this extended return.
1930 if Nkind (N) = N_Extended_Return_Statement then
1931 Push_Scope (Stm_Entity);
1934 -- Check that pragma No_Return is obeyed. Don't complain about the
1935 -- implicitly-generated return that is placed at the end.
1937 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1938 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1941 -- Warn on any unassigned OUT parameters if in procedure
1943 if Ekind (Scope_Id) = E_Procedure then
1944 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1947 -- Check that functions return objects, and other things do not
1949 if Kind = E_Function or else Kind = E_Generic_Function then
1950 if not Returns_Object then
1951 Error_Msg_N ("missing expression in return from function", N);
1954 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1955 if Returns_Object then
1956 Error_Msg_N ("procedure cannot return value (use function)", N);
1959 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1960 if Returns_Object then
1961 if Is_Protected_Type (Scope (Scope_Id)) then
1962 Error_Msg_N ("entry body cannot return value", N);
1964 Error_Msg_N ("accept statement cannot return value", N);
1968 elsif Kind = E_Return_Statement then
1970 -- We are nested within another return statement, which must be an
1971 -- extended_return_statement.
1973 if Returns_Object then
1974 if Nkind (N) = N_Extended_Return_Statement then
1976 ("extended return statement cannot be nested (use `RETURN;`)",
1979 -- Case of a simple return statement with a value inside extended
1980 -- return statement.
1984 ("return nested in extended return statement cannot return "
1985 & "value (use `RETURN;`)", N);
1990 Error_Msg_N ("illegal context for return statement", N);
1993 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1994 Analyze_Function_Return (N);
1996 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1997 Set_Return_Present (Scope_Id);
2000 if Nkind (N) = N_Extended_Return_Statement then
2004 Kill_Current_Values (Last_Assignment_Only => True);
2005 Check_Unreachable_Code (N);
2007 Analyze_Dimension (N);
2008 end Analyze_Return_Statement;
2010 -------------------------------------
2011 -- Analyze_Simple_Return_Statement --
2012 -------------------------------------
2014 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2016 if Present (Expression (N)) then
2017 Mark_Coextensions (N, Expression (N));
2020 Analyze_Return_Statement (N);
2021 end Analyze_Simple_Return_Statement;
2023 -------------------------
2024 -- Analyze_Return_Type --
2025 -------------------------
2027 procedure Analyze_Return_Type (N : Node_Id) is
2028 Designator : constant Entity_Id := Defining_Entity (N);
2029 Typ : Entity_Id := Empty;
2032 -- Normal case where result definition does not indicate an error
2034 if Result_Definition (N) /= Error then
2035 if Nkind (Result_Definition (N)) = N_Access_Definition then
2036 Check_SPARK_05_Restriction
2037 ("access result is not allowed", Result_Definition (N));
2039 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2042 AD : constant Node_Id :=
2043 Access_To_Subprogram_Definition (Result_Definition (N));
2045 if Present (AD) and then Protected_Present (AD) then
2046 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2048 Typ := Access_Definition (N, Result_Definition (N));
2052 Set_Parent (Typ, Result_Definition (N));
2053 Set_Is_Local_Anonymous_Access (Typ);
2054 Set_Etype (Designator, Typ);
2056 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2058 Null_Exclusion_Static_Checks (N);
2060 -- Subtype_Mark case
2063 Find_Type (Result_Definition (N));
2064 Typ := Entity (Result_Definition (N));
2065 Set_Etype (Designator, Typ);
2067 -- Unconstrained array as result is not allowed in SPARK
2069 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2070 Check_SPARK_05_Restriction
2071 ("returning an unconstrained array is not allowed",
2072 Result_Definition (N));
2075 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2077 Null_Exclusion_Static_Checks (N);
2079 -- If a null exclusion is imposed on the result type, then create
2080 -- a null-excluding itype (an access subtype) and use it as the
2081 -- function's Etype. Note that the null exclusion checks are done
2082 -- right before this, because they don't get applied to types that
2083 -- do not come from source.
2085 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2086 Set_Etype (Designator,
2087 Create_Null_Excluding_Itype
2090 Scope_Id => Scope (Current_Scope)));
2092 -- The new subtype must be elaborated before use because
2093 -- it is visible outside of the function. However its base
2094 -- type may not be frozen yet, so the reference that will
2095 -- force elaboration must be attached to the freezing of
2098 -- If the return specification appears on a proper body,
2099 -- the subtype will have been created already on the spec.
2101 if Is_Frozen (Typ) then
2102 if Nkind (Parent (N)) = N_Subprogram_Body
2103 and then Nkind (Parent (Parent (N))) = N_Subunit
2107 Build_Itype_Reference (Etype (Designator), Parent (N));
2111 Ensure_Freeze_Node (Typ);
2114 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2116 Set_Itype (IR, Etype (Designator));
2117 Append_Freeze_Actions (Typ, New_List (IR));
2122 Set_Etype (Designator, Typ);
2125 if Ekind (Typ) = E_Incomplete_Type
2126 or else (Is_Class_Wide_Type (Typ)
2127 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2129 -- AI05-0151: Tagged incomplete types are allowed in all formal
2130 -- parts. Untagged incomplete types are not allowed in bodies.
2131 -- As a consequence, limited views cannot appear in a basic
2132 -- declaration that is itself within a body, because there is
2133 -- no point at which the non-limited view will become visible.
2135 if Ada_Version >= Ada_2012 then
2136 if From_Limited_With (Typ) and then In_Package_Body then
2138 ("invalid use of incomplete type&",
2139 Result_Definition (N), Typ);
2141 -- The return type of a subprogram body cannot be of a
2142 -- formal incomplete type.
2144 elsif Is_Generic_Type (Typ)
2145 and then Nkind (Parent (N)) = N_Subprogram_Body
2148 ("return type cannot be a formal incomplete type",
2149 Result_Definition (N));
2151 elsif Is_Class_Wide_Type (Typ)
2152 and then Is_Generic_Type (Root_Type (Typ))
2153 and then Nkind (Parent (N)) = N_Subprogram_Body
2156 ("return type cannot be a formal incomplete type",
2157 Result_Definition (N));
2159 elsif Is_Tagged_Type (Typ) then
2162 -- Use is legal in a thunk generated for an operation
2163 -- inherited from a progenitor.
2165 elsif Is_Thunk (Designator)
2166 and then Present (Non_Limited_View (Typ))
2170 elsif Nkind (Parent (N)) = N_Subprogram_Body
2171 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2175 ("invalid use of untagged incomplete type&",
2179 -- The type must be completed in the current package. This
2180 -- is checked at the end of the package declaration when
2181 -- Taft-amendment types are identified. If the return type
2182 -- is class-wide, there is no required check, the type can
2183 -- be a bona fide TAT.
2185 if Ekind (Scope (Current_Scope)) = E_Package
2186 and then In_Private_Part (Scope (Current_Scope))
2187 and then not Is_Class_Wide_Type (Typ)
2189 Append_Elmt (Designator, Private_Dependents (Typ));
2194 ("invalid use of incomplete type&", Designator, Typ);
2199 -- Case where result definition does indicate an error
2202 Set_Etype (Designator, Any_Type);
2204 end Analyze_Return_Type;
2206 -----------------------------
2207 -- Analyze_Subprogram_Body --
2208 -----------------------------
2210 procedure Analyze_Subprogram_Body (N : Node_Id) is
2211 Loc : constant Source_Ptr := Sloc (N);
2212 Body_Spec : constant Node_Id := Specification (N);
2213 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2216 if Debug_Flag_C then
2217 Write_Str ("==> subprogram body ");
2218 Write_Name (Chars (Body_Id));
2219 Write_Str (" from ");
2220 Write_Location (Loc);
2225 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2227 -- The real work is split out into the helper, so it can do "return;"
2228 -- without skipping the debug output:
2230 Analyze_Subprogram_Body_Helper (N);
2232 if Debug_Flag_C then
2234 Write_Str ("<== subprogram body ");
2235 Write_Name (Chars (Body_Id));
2236 Write_Str (" from ");
2237 Write_Location (Loc);
2240 end Analyze_Subprogram_Body;
2242 ------------------------------------
2243 -- Analyze_Subprogram_Body_Helper --
2244 ------------------------------------
2246 -- This procedure is called for regular subprogram bodies, generic bodies,
2247 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2248 -- specification matters, and is used to create a proper declaration for
2249 -- the subprogram, or to perform conformance checks.
2251 -- WARNING: This routine manages Ghost regions. Return statements must be
2252 -- replaced by gotos which jump to the end of the routine and restore the
2255 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2256 Body_Spec : Node_Id := Specification (N);
2257 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2258 Loc : constant Source_Ptr := Sloc (N);
2259 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2261 Conformant : Boolean;
2262 Desig_View : Entity_Id := Empty;
2263 Exch_Views : Elist_Id := No_Elist;
2265 Mask_Types : Elist_Id := No_Elist;
2266 Prot_Typ : Entity_Id := Empty;
2267 Spec_Decl : Node_Id := Empty;
2268 Spec_Id : Entity_Id;
2270 Last_Real_Spec_Entity : Entity_Id := Empty;
2271 -- When we analyze a separate spec, the entity chain ends up containing
2272 -- the formals, as well as any itypes generated during analysis of the
2273 -- default expressions for parameters, or the arguments of associated
2274 -- precondition/postcondition pragmas (which are analyzed in the context
2275 -- of the spec since they have visibility on formals).
2277 -- These entities belong with the spec and not the body. However we do
2278 -- the analysis of the body in the context of the spec (again to obtain
2279 -- visibility to the formals), and all the entities generated during
2280 -- this analysis end up also chained to the entity chain of the spec.
2281 -- But they really belong to the body, and there is circuitry to move
2282 -- them from the spec to the body.
2284 -- However, when we do this move, we don't want to move the real spec
2285 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2286 -- variable points to the last real spec entity, so we only move those
2287 -- chained beyond that point. It is initialized to Empty to deal with
2288 -- the case where there is no separate spec.
2290 function Body_Has_Contract return Boolean;
2291 -- Check whether unanalyzed body has an aspect or pragma that may
2292 -- generate a SPARK contract.
2294 function Body_Has_SPARK_Mode_On return Boolean;
2295 -- Check whether SPARK_Mode On applies to the subprogram body, either
2296 -- because it is specified directly on the body, or because it is
2297 -- inherited from the enclosing subprogram or package.
2299 procedure Build_Subprogram_Declaration;
2300 -- Create a matching subprogram declaration for subprogram body N
2302 procedure Check_Anonymous_Return;
2303 -- Ada 2005: if a function returns an access type that denotes a task,
2304 -- or a type that contains tasks, we must create a master entity for
2305 -- the anonymous type, which typically will be used in an allocator
2306 -- in the body of the function.
2308 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2309 -- Look ahead to recognize a pragma that may appear after the body.
2310 -- If there is a previous spec, check that it appears in the same
2311 -- declarative part. If the pragma is Inline_Always, perform inlining
2312 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2313 -- If the body acts as a spec, and inlining is required, we create a
2314 -- subprogram declaration for it, in order to attach the body to inline.
2315 -- If pragma does not appear after the body, check whether there is
2316 -- an inline pragma before any local declarations.
2318 procedure Check_Missing_Return;
2319 -- Checks for a function with a no return statements, and also performs
2320 -- the warning checks implemented by Check_Returns. In formal mode, also
2321 -- verify that a function ends with a RETURN and that a procedure does
2322 -- not contain any RETURN.
2324 function Disambiguate_Spec return Entity_Id;
2325 -- When a primitive is declared between the private view and the full
2326 -- view of a concurrent type which implements an interface, a special
2327 -- mechanism is used to find the corresponding spec of the primitive
2330 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2331 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2332 -- incomplete types coming from a limited context and replace their
2333 -- limited views with the non-limited ones. Return the list of changes
2334 -- to be used to undo the transformation.
2336 function Is_Private_Concurrent_Primitive
2337 (Subp_Id : Entity_Id) return Boolean;
2338 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2339 -- type that implements an interface and has a private view.
2341 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2342 -- N is the body generated for an expression function that is not a
2343 -- completion and Spec_Id the defining entity of its spec. Mark all
2344 -- the not-yet-frozen types referenced by the simple return statement
2345 -- of the function as formally frozen.
2347 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2348 -- Undo the transformation done by Exchange_Limited_Views.
2350 procedure Set_Trivial_Subprogram (N : Node_Id);
2351 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2352 -- subprogram whose body is being analyzed. N is the statement node
2353 -- causing the flag to be set, if the following statement is a return
2354 -- of an entity, we mark the entity as set in source to suppress any
2355 -- warning on the stylized use of function stubs with a dummy return.
2357 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2358 -- Undo the transformation done by Mask_Unfrozen_Types
2360 procedure Verify_Overriding_Indicator;
2361 -- If there was a previous spec, the entity has been entered in the
2362 -- current scope previously. If the body itself carries an overriding
2363 -- indicator, check that it is consistent with the known status of the
2366 -----------------------
2367 -- Body_Has_Contract --
2368 -----------------------
2370 function Body_Has_Contract return Boolean is
2371 Decls : constant List_Id := Declarations (N);
2375 -- Check for aspects that may generate a contract
2377 if Present (Aspect_Specifications (N)) then
2378 Item := First (Aspect_Specifications (N));
2379 while Present (Item) loop
2380 if Is_Subprogram_Contract_Annotation (Item) then
2388 -- Check for pragmas that may generate a contract
2390 if Present (Decls) then
2391 Item := First (Decls);
2392 while Present (Item) loop
2393 if Nkind (Item) = N_Pragma
2394 and then Is_Subprogram_Contract_Annotation (Item)
2404 end Body_Has_Contract;
2406 ----------------------------
2407 -- Body_Has_SPARK_Mode_On --
2408 ----------------------------
2410 function Body_Has_SPARK_Mode_On return Boolean is
2411 Decls : constant List_Id := Declarations (N);
2415 -- Check for SPARK_Mode aspect
2417 if Present (Aspect_Specifications (N)) then
2418 Item := First (Aspect_Specifications (N));
2419 while Present (Item) loop
2420 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2421 return Get_SPARK_Mode_From_Annotation (Item) = On;
2428 -- Check for SPARK_Mode pragma
2430 if Present (Decls) then
2431 Item := First (Decls);
2432 while Present (Item) loop
2434 -- Pragmas that apply to a subprogram body are usually grouped
2435 -- together. Look for a potential pragma SPARK_Mode among them.
2437 if Nkind (Item) = N_Pragma then
2438 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2439 return Get_SPARK_Mode_From_Annotation (Item) = On;
2442 -- Otherwise the first non-pragma declarative item terminates
2443 -- the region where pragma SPARK_Mode may appear.
2453 -- Otherwise, the applicable SPARK_Mode is inherited from the
2454 -- enclosing subprogram or package.
2456 return SPARK_Mode = On;
2457 end Body_Has_SPARK_Mode_On;
2459 ----------------------------------
2460 -- Build_Subprogram_Declaration --
2461 ----------------------------------
2463 procedure Build_Subprogram_Declaration is
2464 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2465 -- Relocate certain categorization pragmas from the declarative list
2466 -- of subprogram body From and insert them after node To. The pragmas
2469 -- Volatile_Function
2470 -- Also copy pragma SPARK_Mode if present in the declarative list
2471 -- of subprogram body From and insert it after node To. This pragma
2472 -- should not be moved, as it applies to the body too.
2478 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2480 Next_Decl : Node_Id;
2483 pragma Assert (Nkind (From) = N_Subprogram_Body);
2485 -- The destination node must be part of a list, as the pragmas are
2486 -- inserted after it.
2488 pragma Assert (Is_List_Member (To));
2490 -- Inspect the declarations of the subprogram body looking for
2491 -- specific pragmas.
2493 Decl := First (Declarations (N));
2494 while Present (Decl) loop
2495 Next_Decl := Next (Decl);
2497 if Nkind (Decl) = N_Pragma then
2498 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2499 Insert_After (To, New_Copy_Tree (Decl));
2501 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2503 Name_Volatile_Function)
2506 Insert_After (To, Decl);
2517 Subp_Decl : Node_Id;
2519 -- Start of processing for Build_Subprogram_Declaration
2522 -- Create a matching subprogram spec using the profile of the body.
2523 -- The structure of the tree is identical, but has new entities for
2524 -- the defining unit name and formal parameters.
2527 Make_Subprogram_Declaration (Loc,
2528 Specification => Copy_Subprogram_Spec (Body_Spec));
2529 Set_Comes_From_Source (Subp_Decl, True);
2531 -- Also mark parameters as coming from source
2533 if Present (Parameter_Specifications (Specification (Subp_Decl))) then
2538 First (Parameter_Specifications (Specification (Subp_Decl)));
2540 while Present (Form) loop
2541 Set_Comes_From_Source (Defining_Identifier (Form), True);
2547 -- Relocate the aspects and relevant pragmas from the subprogram body
2548 -- to the generated spec because it acts as the initial declaration.
2550 Insert_Before (N, Subp_Decl);
2551 Move_Aspects (N, To => Subp_Decl);
2552 Move_Pragmas (N, To => Subp_Decl);
2554 -- Ensure that the generated corresponding spec and original body
2555 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2556 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2557 -- correctly set for local subprograms.
2559 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2561 Analyze (Subp_Decl);
2563 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2564 -- the body since the expander may generate calls using that entity.
2565 -- Required to ensure that Expand_Call rewrites calls to this
2566 -- function by calls to the built procedure.
2568 if Modify_Tree_For_C
2569 and then Nkind (Body_Spec) = N_Function_Specification
2571 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2573 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2574 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2575 Corresponding_Procedure
2576 (Defining_Entity (Specification (Subp_Decl))));
2579 -- Analyze any relocated source pragmas or pragmas created for aspect
2582 Decl := Next (Subp_Decl);
2583 while Present (Decl) loop
2585 -- Stop the search for pragmas once the body has been reached as
2586 -- this terminates the region where pragmas may appear.
2591 elsif Nkind (Decl) = N_Pragma then
2598 Spec_Id := Defining_Entity (Subp_Decl);
2599 Set_Corresponding_Spec (N, Spec_Id);
2601 -- Mark the generated spec as a source construct to ensure that all
2602 -- calls to it are properly registered in ALI files for GNATprove.
2604 Set_Comes_From_Source (Spec_Id, True);
2606 -- Ensure that the specs of the subprogram declaration and its body
2607 -- are identical, otherwise they will appear non-conformant due to
2608 -- rewritings in the default values of formal parameters.
2610 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2611 Set_Specification (N, Body_Spec);
2612 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2613 end Build_Subprogram_Declaration;
2615 ----------------------------
2616 -- Check_Anonymous_Return --
2617 ----------------------------
2619 procedure Check_Anonymous_Return is
2625 if Present (Spec_Id) then
2631 if Ekind (Scop) = E_Function
2632 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2633 and then not Is_Thunk (Scop)
2635 -- Skip internally built functions which handle the case of
2636 -- a null access (see Expand_Interface_Conversion)
2638 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2639 and then not Comes_From_Source (Parent (Scop)))
2641 and then (Has_Task (Designated_Type (Etype (Scop)))
2643 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2645 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2646 and then Expander_Active
2648 -- Avoid cases with no tasking support
2650 and then RTE_Available (RE_Current_Master)
2651 and then not Restriction_Active (No_Task_Hierarchy)
2654 Make_Object_Declaration (Loc,
2655 Defining_Identifier =>
2656 Make_Defining_Identifier (Loc, Name_uMaster),
2657 Constant_Present => True,
2658 Object_Definition =>
2659 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2661 Make_Explicit_Dereference (Loc,
2662 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2664 if Present (Declarations (N)) then
2665 Prepend (Decl, Declarations (N));
2667 Set_Declarations (N, New_List (Decl));
2670 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2671 Set_Has_Master_Entity (Scop);
2673 -- Now mark the containing scope as a task master
2676 while Nkind (Par) /= N_Compilation_Unit loop
2677 Par := Parent (Par);
2678 pragma Assert (Present (Par));
2680 -- If we fall off the top, we are at the outer level, and
2681 -- the environment task is our effective master, so nothing
2685 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2687 Set_Is_Task_Master (Par, True);
2692 end Check_Anonymous_Return;
2694 -------------------------
2695 -- Check_Inline_Pragma --
2696 -------------------------
2698 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2702 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2703 -- True when N is a pragma Inline or Inline_Always that applies
2704 -- to this subprogram.
2706 -----------------------
2707 -- Is_Inline_Pragma --
2708 -----------------------
2710 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2712 if Nkind (N) = N_Pragma
2714 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2715 or else (Pragma_Name_Unmapped (N) = Name_Inline
2717 (Front_End_Inlining or else Optimization_Level > 0)))
2718 and then Present (Pragma_Argument_Associations (N))
2721 Pragma_Arg : Node_Id :=
2722 Expression (First (Pragma_Argument_Associations (N)));
2724 if Nkind (Pragma_Arg) = N_Selected_Component then
2725 Pragma_Arg := Selector_Name (Pragma_Arg);
2728 return Chars (Pragma_Arg) = Chars (Body_Id);
2734 end Is_Inline_Pragma;
2736 -- Start of processing for Check_Inline_Pragma
2739 if not Expander_Active then
2743 if Is_List_Member (N)
2744 and then Present (Next (N))
2745 and then Is_Inline_Pragma (Next (N))
2749 elsif Nkind (N) /= N_Subprogram_Body_Stub
2750 and then Present (Declarations (N))
2751 and then Is_Inline_Pragma (First (Declarations (N)))
2753 Prag := First (Declarations (N));
2759 if Present (Prag) then
2760 if Present (Spec_Id) then
2761 if Is_List_Member (N)
2762 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2763 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2769 -- Create a subprogram declaration, to make treatment uniform.
2770 -- Make the sloc of the subprogram name that of the entity in
2771 -- the body, so that style checks find identical strings.
2774 Subp : constant Entity_Id :=
2775 Make_Defining_Identifier
2776 (Sloc (Body_Id), Chars (Body_Id));
2777 Decl : constant Node_Id :=
2778 Make_Subprogram_Declaration (Loc,
2780 New_Copy_Tree (Specification (N)));
2783 -- Link the body and the generated spec
2785 Set_Corresponding_Body (Decl, Body_Id);
2786 Set_Corresponding_Spec (N, Subp);
2788 Set_Defining_Unit_Name (Specification (Decl), Subp);
2790 -- To ensure proper coverage when body is inlined, indicate
2791 -- whether the subprogram comes from source.
2793 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2795 if Present (First_Formal (Body_Id)) then
2796 Plist := Copy_Parameter_List (Body_Id);
2797 Set_Parameter_Specifications
2798 (Specification (Decl), Plist);
2801 -- Move aspects to the new spec
2803 if Has_Aspects (N) then
2804 Move_Aspects (N, To => Decl);
2807 Insert_Before (N, Decl);
2810 Set_Has_Pragma_Inline (Subp);
2812 if Pragma_Name (Prag) = Name_Inline_Always then
2813 Set_Is_Inlined (Subp);
2814 Set_Has_Pragma_Inline_Always (Subp);
2817 -- Prior to copying the subprogram body to create a template
2818 -- for it for subsequent inlining, remove the pragma from
2819 -- the current body so that the copy that will produce the
2820 -- new body will start from a completely unanalyzed tree.
2822 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2823 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2830 end Check_Inline_Pragma;
2832 --------------------------
2833 -- Check_Missing_Return --
2834 --------------------------
2836 procedure Check_Missing_Return is
2838 Missing_Ret : Boolean;
2841 if Nkind (Body_Spec) = N_Function_Specification then
2842 if Present (Spec_Id) then
2848 if Return_Present (Id) then
2849 Check_Returns (HSS, 'F', Missing_Ret);
2852 Set_Has_Missing_Return (Id);
2855 -- Within a premature instantiation of a package with no body, we
2856 -- build completions of the functions therein, with a Raise
2857 -- statement. No point in complaining about a missing return in
2860 elsif Ekind (Id) = E_Function
2861 and then In_Instance
2862 and then Present (Statements (HSS))
2863 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2867 elsif Is_Generic_Subprogram (Id)
2868 or else not Is_Machine_Code_Subprogram (Id)
2870 Error_Msg_N ("missing RETURN statement in function body", N);
2873 -- If procedure with No_Return, check returns
2875 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2876 if Present (Spec_Id) then
2882 if No_Return (Id) then
2883 Check_Returns (HSS, 'P', Missing_Ret, Id);
2887 -- Special checks in SPARK mode
2889 if Nkind (Body_Spec) = N_Function_Specification then
2891 -- In SPARK mode, last statement of a function should be a return
2894 Stat : constant Node_Id := Last_Source_Statement (HSS);
2897 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2898 N_Extended_Return_Statement)
2900 Check_SPARK_05_Restriction
2901 ("last statement in function should be RETURN", Stat);
2905 -- In SPARK mode, verify that a procedure has no return
2907 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2908 if Present (Spec_Id) then
2914 -- Would be nice to point to return statement here, can we
2915 -- borrow the Check_Returns procedure here ???
2917 if Return_Present (Id) then
2918 Check_SPARK_05_Restriction
2919 ("procedure should not have RETURN", N);
2922 end Check_Missing_Return;
2924 -----------------------
2925 -- Disambiguate_Spec --
2926 -----------------------
2928 function Disambiguate_Spec return Entity_Id is
2929 Priv_Spec : Entity_Id;
2932 procedure Replace_Types (To_Corresponding : Boolean);
2933 -- Depending on the flag, replace the type of formal parameters of
2934 -- Body_Id if it is a concurrent type implementing interfaces with
2935 -- the corresponding record type or the other way around.
2937 procedure Replace_Types (To_Corresponding : Boolean) is
2939 Formal_Typ : Entity_Id;
2942 Formal := First_Formal (Body_Id);
2943 while Present (Formal) loop
2944 Formal_Typ := Etype (Formal);
2946 if Is_Class_Wide_Type (Formal_Typ) then
2947 Formal_Typ := Root_Type (Formal_Typ);
2950 -- From concurrent type to corresponding record
2952 if To_Corresponding then
2953 if Is_Concurrent_Type (Formal_Typ)
2954 and then Present (Corresponding_Record_Type (Formal_Typ))
2957 (Corresponding_Record_Type (Formal_Typ)))
2960 Corresponding_Record_Type (Formal_Typ));
2963 -- From corresponding record to concurrent type
2966 if Is_Concurrent_Record_Type (Formal_Typ)
2967 and then Present (Interfaces (Formal_Typ))
2970 Corresponding_Concurrent_Type (Formal_Typ));
2974 Next_Formal (Formal);
2978 -- Start of processing for Disambiguate_Spec
2981 -- Try to retrieve the specification of the body as is. All error
2982 -- messages are suppressed because the body may not have a spec in
2983 -- its current state.
2985 Spec_N := Find_Corresponding_Spec (N, False);
2987 -- It is possible that this is the body of a primitive declared
2988 -- between a private and a full view of a concurrent type. The
2989 -- controlling parameter of the spec carries the concurrent type,
2990 -- not the corresponding record type as transformed by Analyze_
2991 -- Subprogram_Specification. In such cases, we undo the change
2992 -- made by the analysis of the specification and try to find the
2995 -- Note that wrappers already have their corresponding specs and
2996 -- bodies set during their creation, so if the candidate spec is
2997 -- a wrapper, then we definitely need to swap all types to their
2998 -- original concurrent status.
3001 or else Is_Primitive_Wrapper (Spec_N)
3003 -- Restore all references of corresponding record types to the
3004 -- original concurrent types.
3006 Replace_Types (To_Corresponding => False);
3007 Priv_Spec := Find_Corresponding_Spec (N, False);
3009 -- The current body truly belongs to a primitive declared between
3010 -- a private and a full view. We leave the modified body as is,
3011 -- and return the true spec.
3013 if Present (Priv_Spec)
3014 and then Is_Private_Primitive (Priv_Spec)
3019 -- In case that this is some sort of error, restore the original
3020 -- state of the body.
3022 Replace_Types (To_Corresponding => True);
3026 end Disambiguate_Spec;
3028 ----------------------------
3029 -- Exchange_Limited_Views --
3030 ----------------------------
3032 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3033 Result : Elist_Id := No_Elist;
3035 procedure Detect_And_Exchange (Id : Entity_Id);
3036 -- Determine whether Id's type denotes an incomplete type associated
3037 -- with a limited with clause and exchange the limited view with the
3038 -- non-limited one when available. Note that the non-limited view
3039 -- may exist because of a with_clause in another unit in the context,
3040 -- but cannot be used because the current view of the enclosing unit
3041 -- is still a limited view.
3043 -------------------------
3044 -- Detect_And_Exchange --
3045 -------------------------
3047 procedure Detect_And_Exchange (Id : Entity_Id) is
3048 Typ : constant Entity_Id := Etype (Id);
3050 if From_Limited_With (Typ)
3051 and then Has_Non_Limited_View (Typ)
3052 and then not From_Limited_With (Scope (Typ))
3055 Result := New_Elmt_List;
3058 Prepend_Elmt (Typ, Result);
3059 Prepend_Elmt (Id, Result);
3060 Set_Etype (Id, Non_Limited_View (Typ));
3062 end Detect_And_Exchange;
3068 -- Start of processing for Exchange_Limited_Views
3071 -- Do not process subprogram bodies as they already use the non-
3072 -- limited view of types.
3074 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3078 -- Examine all formals and swap views when applicable
3080 Formal := First_Formal (Subp_Id);
3081 while Present (Formal) loop
3082 Detect_And_Exchange (Formal);
3084 Next_Formal (Formal);
3087 -- Process the return type of a function
3089 if Ekind (Subp_Id) = E_Function then
3090 Detect_And_Exchange (Subp_Id);
3094 end Exchange_Limited_Views;
3096 -------------------------------------
3097 -- Is_Private_Concurrent_Primitive --
3098 -------------------------------------
3100 function Is_Private_Concurrent_Primitive
3101 (Subp_Id : Entity_Id) return Boolean
3103 Formal_Typ : Entity_Id;
3106 if Present (First_Formal (Subp_Id)) then
3107 Formal_Typ := Etype (First_Formal (Subp_Id));
3109 if Is_Concurrent_Record_Type (Formal_Typ) then
3110 if Is_Class_Wide_Type (Formal_Typ) then
3111 Formal_Typ := Root_Type (Formal_Typ);
3114 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3117 -- The type of the first formal is a concurrent tagged type with
3121 Is_Concurrent_Type (Formal_Typ)
3122 and then Is_Tagged_Type (Formal_Typ)
3123 and then Has_Private_Declaration (Formal_Typ);
3127 end Is_Private_Concurrent_Primitive;
3129 -------------------------
3130 -- Mask_Unfrozen_Types --
3131 -------------------------
3133 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3134 Result : Elist_Id := No_Elist;
3136 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3137 -- Mask all types referenced in the subtree rooted at Node
3139 --------------------
3140 -- Mask_Type_Refs --
3141 --------------------
3143 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3144 procedure Mask_Type (Typ : Entity_Id);
3145 -- ??? what does this do?
3151 procedure Mask_Type (Typ : Entity_Id) is
3153 -- Skip Itypes created by the preanalysis
3156 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3161 if not Is_Frozen (Typ) then
3162 if Scope (Typ) /= Current_Scope then
3163 Set_Is_Frozen (Typ);
3164 Append_New_Elmt (Typ, Result);
3166 Freeze_Before (N, Typ);
3171 -- Start of processing for Mask_Type_Refs
3174 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3175 Mask_Type (Etype (Entity (Node)));
3177 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3178 Mask_Type (Scope (Entity (Node)));
3181 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3182 and then Present (Etype (Node))
3184 Mask_Type (Etype (Node));
3190 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3194 Return_Stmt : constant Node_Id :=
3195 First (Statements (Handled_Statement_Sequence (N)));
3197 -- Start of processing for Mask_Unfrozen_Types
3200 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3202 Mask_References (Expression (Return_Stmt));
3205 end Mask_Unfrozen_Types;
3207 ---------------------------
3208 -- Restore_Limited_Views --
3209 ---------------------------
3211 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3212 Elmt : Elmt_Id := First_Elmt (Restore_List);
3216 while Present (Elmt) loop
3219 Set_Etype (Id, Node (Elmt));
3222 end Restore_Limited_Views;
3224 ----------------------------
3225 -- Set_Trivial_Subprogram --
3226 ----------------------------
3228 procedure Set_Trivial_Subprogram (N : Node_Id) is
3229 Nxt : constant Node_Id := Next (N);
3232 Set_Is_Trivial_Subprogram (Body_Id);
3234 if Present (Spec_Id) then
3235 Set_Is_Trivial_Subprogram (Spec_Id);
3239 and then Nkind (Nxt) = N_Simple_Return_Statement
3240 and then No (Next (Nxt))
3241 and then Present (Expression (Nxt))
3242 and then Is_Entity_Name (Expression (Nxt))
3244 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3246 end Set_Trivial_Subprogram;
3248 ---------------------------
3249 -- Unmask_Unfrozen_Types --
3250 ---------------------------
3252 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3253 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3256 while Present (Elmt) loop
3257 Set_Is_Frozen (Node (Elmt), False);
3260 end Unmask_Unfrozen_Types;
3262 ---------------------------------
3263 -- Verify_Overriding_Indicator --
3264 ---------------------------------
3266 procedure Verify_Overriding_Indicator is
3268 if Must_Override (Body_Spec) then
3269 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3270 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3274 elsif not Present (Overridden_Operation (Spec_Id)) then
3276 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3278 -- Overriding indicators aren't allowed for protected subprogram
3279 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3280 -- this to a warning if -gnatd.E is enabled.
3282 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3283 Error_Msg_Warn := Error_To_Warning;
3285 ("<<overriding indicator not allowed for protected "
3286 & "subprogram body", Body_Spec);
3289 elsif Must_Not_Override (Body_Spec) then
3290 if Present (Overridden_Operation (Spec_Id)) then
3292 ("subprogram& overrides inherited operation",
3293 Body_Spec, Spec_Id);
3295 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3296 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3299 ("subprogram& overrides predefined operator ",
3300 Body_Spec, Spec_Id);
3302 -- Overriding indicators aren't allowed for protected subprogram
3303 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3304 -- this to a warning if -gnatd.E is enabled.
3306 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3307 Error_Msg_Warn := Error_To_Warning;
3310 ("<<overriding indicator not allowed "
3311 & "for protected subprogram body", Body_Spec);
3313 -- If this is not a primitive operation, then the overriding
3314 -- indicator is altogether illegal.
3316 elsif not Is_Primitive (Spec_Id) then
3318 ("overriding indicator only allowed "
3319 & "if subprogram is primitive", Body_Spec);
3322 -- If checking the style rule and the operation overrides, then
3323 -- issue a warning about a missing overriding_indicator. Protected
3324 -- subprogram bodies are excluded from this style checking, since
3325 -- they aren't primitives (even though their declarations can
3326 -- override) and aren't allowed to have an overriding_indicator.
3329 and then Present (Overridden_Operation (Spec_Id))
3330 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3332 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3333 Style.Missing_Overriding (N, Body_Id);
3336 and then Can_Override_Operator (Spec_Id)
3337 and then not In_Predefined_Unit (Spec_Id)
3339 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3340 Style.Missing_Overriding (N, Body_Id);
3342 end Verify_Overriding_Indicator;
3346 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3347 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3348 Saved_ISMP : constant Boolean :=
3349 Ignore_SPARK_Mode_Pragmas_In_Instance;
3350 -- Save the Ghost and SPARK mode-related data to restore on exit
3352 -- Start of processing for Analyze_Subprogram_Body_Helper
3355 -- A [generic] subprogram body freezes the contract of the nearest
3356 -- enclosing package body and all other contracts encountered in the
3357 -- same declarative part up to and excluding the subprogram body:
3359 -- package body Nearest_Enclosing_Package
3360 -- with Refined_State => (State => Constit)
3364 -- procedure Freezes_Enclosing_Package_Body
3365 -- with Refined_Depends => (Input => Constit) ...
3367 -- This ensures that any annotations referenced by the contract of the
3368 -- [generic] subprogram body are available. This form of freezing is
3369 -- decoupled from the usual Freeze_xxx mechanism because it must also
3370 -- work in the context of generics where normal freezing is disabled.
3372 -- Only bodies coming from source should cause this type of freezing.
3373 -- Expression functions that act as bodies and complete an initial
3374 -- declaration must be included in this category, hence the use of
3377 if Comes_From_Source (Original_Node (N)) then
3378 Freeze_Previous_Contracts (N);
3381 -- Generic subprograms are handled separately. They always have a
3382 -- generic specification. Determine whether current scope has a
3383 -- previous declaration.
3385 -- If the subprogram body is defined within an instance of the same
3386 -- name, the instance appears as a package renaming, and will be hidden
3387 -- within the subprogram.
3389 if Present (Prev_Id)
3390 and then not Is_Overloadable (Prev_Id)
3391 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3392 or else Comes_From_Source (Prev_Id))
3394 if Is_Generic_Subprogram (Prev_Id) then
3397 -- A subprogram body is Ghost when it is stand alone and subject
3398 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3399 -- the mode now to ensure that any nodes generated during analysis
3400 -- and expansion are properly marked as Ghost.
3402 Mark_And_Set_Ghost_Body (N, Spec_Id);
3404 -- If the body completes the initial declaration of a compilation
3405 -- unit which is subject to pragma Elaboration_Checks, set the
3406 -- model specified by the pragma because it applies to all parts
3409 Install_Elaboration_Model (Spec_Id);
3411 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3412 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3414 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3416 if Nkind (N) = N_Subprogram_Body then
3417 HSS := Handled_Statement_Sequence (N);
3418 Check_Missing_Return;
3423 -- Otherwise a previous entity conflicts with the subprogram name.
3424 -- Attempting to enter name will post error.
3427 Enter_Name (Body_Id);
3431 -- Non-generic case, find the subprogram declaration, if one was seen,
3432 -- or enter new overloaded entity in the current scope. If the
3433 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3434 -- part of the context of one of its subunits. No need to redo the
3437 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3441 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3443 if Nkind (N) = N_Subprogram_Body_Stub
3444 or else No (Corresponding_Spec (N))
3446 if Is_Private_Concurrent_Primitive (Body_Id) then
3447 Spec_Id := Disambiguate_Spec;
3449 -- A subprogram body is Ghost when it is stand alone and
3450 -- subject to pragma Ghost or when the corresponding spec is
3451 -- Ghost. Set the mode now to ensure that any nodes generated
3452 -- during analysis and expansion are properly marked as Ghost.
3454 Mark_And_Set_Ghost_Body (N, Spec_Id);
3456 -- If the body completes a compilation unit which is subject
3457 -- to pragma Elaboration_Checks, set the model specified by
3458 -- the pragma because it applies to all parts of the unit.
3460 Install_Elaboration_Model (Spec_Id);
3463 Spec_Id := Find_Corresponding_Spec (N);
3465 -- A subprogram body is Ghost when it is stand alone and
3466 -- subject to pragma Ghost or when the corresponding spec is
3467 -- Ghost. Set the mode now to ensure that any nodes generated
3468 -- during analysis and expansion are properly marked as Ghost.
3470 Mark_And_Set_Ghost_Body (N, Spec_Id);
3472 -- If the body completes a compilation unit which is subject
3473 -- to pragma Elaboration_Checks, set the model specified by
3474 -- the pragma because it applies to all parts of the unit.
3476 Install_Elaboration_Model (Spec_Id);
3478 -- In GNATprove mode, if the body has no previous spec, create
3479 -- one so that the inlining machinery can operate properly.
3480 -- Transfer aspects, if any, to the new spec, so that they
3481 -- are legal and can be processed ahead of the body.
3482 -- We make two copies of the given spec, one for the new
3483 -- declaration, and one for the body.
3485 if No (Spec_Id) and then GNATprove_Mode
3487 -- Inlining does not apply during preanalysis of code
3489 and then Full_Analysis
3491 -- Inlining only applies to full bodies, not stubs
3493 and then Nkind (N) /= N_Subprogram_Body_Stub
3495 -- Inlining only applies to bodies in the source code, not to
3496 -- those generated by the compiler. In particular, expression
3497 -- functions, whose body is generated by the compiler, are
3498 -- treated specially by GNATprove.
3500 and then Comes_From_Source (Body_Id)
3502 -- This cannot be done for a compilation unit, which is not
3503 -- in a context where we can insert a new spec.
3505 and then Is_List_Member (N)
3507 -- Inlining only applies to subprograms without contracts,
3508 -- as a contract is a sign that GNATprove should perform a
3509 -- modular analysis of the subprogram instead of a contextual
3510 -- analysis at each call site. The same test is performed in
3511 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3512 -- here in another form (because the contract has not been
3513 -- attached to the body) to avoid front-end errors in case
3514 -- pragmas are used instead of aspects, because the
3515 -- corresponding pragmas in the body would not be transferred
3516 -- to the spec, leading to legality errors.
3518 and then not Body_Has_Contract
3519 and then not Inside_A_Generic
3521 Build_Subprogram_Declaration;
3523 -- If this is a function that returns a constrained array, and
3524 -- we are generating SPARK_For_C, create subprogram declaration
3525 -- to simplify subsequent C generation.
3528 and then Modify_Tree_For_C
3529 and then Nkind (Body_Spec) = N_Function_Specification
3530 and then Is_Array_Type (Etype (Body_Id))
3531 and then Is_Constrained (Etype (Body_Id))
3533 Build_Subprogram_Declaration;
3537 -- If this is a duplicate body, no point in analyzing it
3539 if Error_Posted (N) then
3543 -- A subprogram body should cause freezing of its own declaration,
3544 -- but if there was no previous explicit declaration, then the
3545 -- subprogram will get frozen too late (there may be code within
3546 -- the body that depends on the subprogram having been frozen,
3547 -- such as uses of extra formals), so we force it to be frozen
3548 -- here. Same holds if the body and spec are compilation units.
3549 -- Finally, if the return type is an anonymous access to protected
3550 -- subprogram, it must be frozen before the body because its
3551 -- expansion has generated an equivalent type that is used when
3552 -- elaborating the body.
3554 -- An exception in the case of Ada 2012, AI05-177: The bodies
3555 -- created for expression functions do not freeze.
3558 and then Nkind (Original_Node (N)) /= N_Expression_Function
3560 Freeze_Before (N, Body_Id);
3562 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3563 Freeze_Before (N, Spec_Id);
3565 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3566 Freeze_Before (N, Etype (Body_Id));
3570 Spec_Id := Corresponding_Spec (N);
3572 -- A subprogram body is Ghost when it is stand alone and subject
3573 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3574 -- the mode now to ensure that any nodes generated during analysis
3575 -- and expansion are properly marked as Ghost.
3577 Mark_And_Set_Ghost_Body (N, Spec_Id);
3579 -- If the body completes the initial declaration of a compilation
3580 -- unit which is subject to pragma Elaboration_Checks, set the
3581 -- model specified by the pragma because it applies to all parts
3584 Install_Elaboration_Model (Spec_Id);
3588 -- Previously we scanned the body to look for nested subprograms, and
3589 -- rejected an inline directive if nested subprograms were present,
3590 -- because the back-end would generate conflicting symbols for the
3591 -- nested bodies. This is now unnecessary.
3593 -- Look ahead to recognize a pragma Inline that appears after the body
3595 Check_Inline_Pragma (Spec_Id);
3597 -- Deal with special case of a fully private operation in the body of
3598 -- the protected type. We must create a declaration for the subprogram,
3599 -- in order to attach the protected subprogram that will be used in
3600 -- internal calls. We exclude compiler generated bodies from the
3601 -- expander since the issue does not arise for those cases.
3604 and then Comes_From_Source (N)
3605 and then Is_Protected_Type (Current_Scope)
3607 Spec_Id := Build_Private_Protected_Declaration (N);
3610 -- If we are generating C and this is a function returning a constrained
3611 -- array type for which we must create a procedure with an extra out
3612 -- parameter, build and analyze the body now. The procedure declaration
3613 -- has already been created. We reuse the source body of the function,
3614 -- because in an instance it may contain global references that cannot
3615 -- be reanalyzed. The source function itself is not used any further,
3616 -- so we mark it as having a completion. If the subprogram is a stub the
3617 -- transformation is done later, when the proper body is analyzed.
3620 and then Modify_Tree_For_C
3621 and then Present (Spec_Id)
3622 and then Ekind (Spec_Id) = E_Function
3623 and then Nkind (N) /= N_Subprogram_Body_Stub
3624 and then Rewritten_For_C (Spec_Id)
3626 Set_Has_Completion (Spec_Id);
3628 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3631 -- The entity for the created procedure must remain invisible, so it
3632 -- does not participate in resolution of subsequent references to the
3635 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3639 -- If a separate spec is present, then deal with freezing issues
3641 if Present (Spec_Id) then
3642 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3643 Verify_Overriding_Indicator;
3645 -- In general, the spec will be frozen when we start analyzing the
3646 -- body. However, for internally generated operations, such as
3647 -- wrapper functions for inherited operations with controlling
3648 -- results, the spec may not have been frozen by the time we expand
3649 -- the freeze actions that include the bodies. In particular, extra
3650 -- formals for accessibility or for return-in-place may need to be
3651 -- generated. Freeze nodes, if any, are inserted before the current
3652 -- body. These freeze actions are also needed in ASIS mode and in
3653 -- Compile_Only mode to enable the proper back-end type annotations.
3654 -- They are necessary in any case to insure order of elaboration
3657 if Nkind (N) = N_Subprogram_Body
3658 and then Was_Expression_Function (N)
3659 and then not Has_Completion (Spec_Id)
3660 and then Serious_Errors_Detected = 0
3661 and then (Expander_Active
3663 or else Operating_Mode = Check_Semantics)
3665 -- The body generated for an expression function that is not a
3666 -- completion is a freeze point neither for the profile nor for
3667 -- anything else. That's why, in order to prevent any freezing
3668 -- during analysis, we need to mask types declared outside the
3669 -- expression (and in an outer scope) that are not yet frozen.
3671 Set_Is_Frozen (Spec_Id);
3672 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3674 elsif not Is_Frozen (Spec_Id)
3675 and then Serious_Errors_Detected = 0
3677 Set_Has_Delayed_Freeze (Spec_Id);
3678 Freeze_Before (N, Spec_Id);
3682 -- If the subprogram has a class-wide clone, build its body as a copy
3683 -- of the original body, and rewrite body of original subprogram as a
3684 -- wrapper that calls the clone. If N is a stub, this construction will
3685 -- take place when the proper body is analyzed. No action needed if this
3686 -- subprogram has been eliminated.
3688 if Present (Spec_Id)
3689 and then Present (Class_Wide_Clone (Spec_Id))
3690 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3691 and then Nkind (N) /= N_Subprogram_Body_Stub
3692 and then not (Expander_Active and then Is_Eliminated (Spec_Id))
3694 Build_Class_Wide_Clone_Body (Spec_Id, N);
3696 -- This is the new body for the existing primitive operation
3698 Rewrite (N, Build_Class_Wide_Clone_Call
3699 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3700 Set_Has_Completion (Spec_Id, False);
3705 -- Place subprogram on scope stack, and make formals visible. If there
3706 -- is a spec, the visible entity remains that of the spec.
3708 if Present (Spec_Id) then
3709 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3711 if Is_Child_Unit (Spec_Id) then
3712 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3716 Style.Check_Identifier (Body_Id, Spec_Id);
3719 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3720 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3722 if Is_Abstract_Subprogram (Spec_Id) then
3723 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3727 Set_Convention (Body_Id, Convention (Spec_Id));
3728 Set_Has_Completion (Spec_Id);
3730 if Is_Protected_Type (Scope (Spec_Id)) then
3731 Prot_Typ := Scope (Spec_Id);
3734 -- If this is a body generated for a renaming, do not check for
3735 -- full conformance. The check is redundant, because the spec of
3736 -- the body is a copy of the spec in the renaming declaration,
3737 -- and the test can lead to spurious errors on nested defaults.
3739 if Present (Spec_Decl)
3740 and then not Comes_From_Source (N)
3742 (Nkind (Original_Node (Spec_Decl)) =
3743 N_Subprogram_Renaming_Declaration
3744 or else (Present (Corresponding_Body (Spec_Decl))
3746 Nkind (Unit_Declaration_Node
3747 (Corresponding_Body (Spec_Decl))) =
3748 N_Subprogram_Renaming_Declaration))
3752 -- Conversely, the spec may have been generated for specless body
3753 -- with an inline pragma. The entity comes from source, which is
3754 -- both semantically correct and necessary for proper inlining.
3755 -- The subprogram declaration itself is not in the source.
3757 elsif Comes_From_Source (N)
3758 and then Present (Spec_Decl)
3759 and then not Comes_From_Source (Spec_Decl)
3760 and then Has_Pragma_Inline (Spec_Id)
3767 Fully_Conformant, True, Conformant, Body_Id);
3770 -- If the body is not fully conformant, we have to decide if we
3771 -- should analyze it or not. If it has a really messed up profile
3772 -- then we probably should not analyze it, since we will get too
3773 -- many bogus messages.
3775 -- Our decision is to go ahead in the non-fully conformant case
3776 -- only if it is at least mode conformant with the spec. Note
3777 -- that the call to Check_Fully_Conformant has issued the proper
3778 -- error messages to complain about the lack of conformance.
3781 and then not Mode_Conformant (Body_Id, Spec_Id)
3787 -- In the case we are dealing with an expression function we check
3788 -- the formals attached to the spec instead of the body - so we don't
3789 -- reference body formals.
3791 if Spec_Id /= Body_Id
3792 and then not Is_Expression_Function (Spec_Id)
3794 Reference_Body_Formals (Spec_Id, Body_Id);
3797 Set_Ekind (Body_Id, E_Subprogram_Body);
3799 if Nkind (N) = N_Subprogram_Body_Stub then
3800 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3805 Set_Corresponding_Spec (N, Spec_Id);
3807 -- Ada 2005 (AI-345): If the operation is a primitive operation
3808 -- of a concurrent type, the type of the first parameter has been
3809 -- replaced with the corresponding record, which is the proper
3810 -- run-time structure to use. However, within the body there may
3811 -- be uses of the formals that depend on primitive operations
3812 -- of the type (in particular calls in prefixed form) for which
3813 -- we need the original concurrent type. The operation may have
3814 -- several controlling formals, so the replacement must be done
3817 if Comes_From_Source (Spec_Id)
3818 and then Present (First_Entity (Spec_Id))
3819 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3820 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3821 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3822 and then Present (Corresponding_Concurrent_Type
3823 (Etype (First_Entity (Spec_Id))))
3826 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3830 Form := First_Formal (Spec_Id);
3831 while Present (Form) loop
3832 if Etype (Form) = Typ then
3833 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3841 -- Make the formals visible, and place subprogram on scope stack.
3842 -- This is also the point at which we set Last_Real_Spec_Entity
3843 -- to mark the entities which will not be moved to the body.
3845 Install_Formals (Spec_Id);
3846 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3848 -- Within an instance, add local renaming declarations so that
3849 -- gdb can retrieve the values of actuals more easily. This is
3850 -- only relevant if generating code (and indeed we definitely
3851 -- do not want these definitions -gnatc mode, because that would
3854 if Is_Generic_Instance (Spec_Id)
3855 and then Is_Wrapper_Package (Current_Scope)
3856 and then Expander_Active
3858 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3861 Push_Scope (Spec_Id);
3863 -- Make sure that the subprogram is immediately visible. For
3864 -- child units that have no separate spec this is indispensable.
3865 -- Otherwise it is safe albeit redundant.
3867 Set_Is_Immediately_Visible (Spec_Id);
3870 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3871 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3872 Set_Scope (Body_Id, Scope (Spec_Id));
3874 -- Case of subprogram body with no previous spec
3877 -- Check for style warning required
3881 -- Only apply check for source level subprograms for which checks
3882 -- have not been suppressed.
3884 and then Comes_From_Source (Body_Id)
3885 and then not Suppress_Style_Checks (Body_Id)
3887 -- No warnings within an instance
3889 and then not In_Instance
3891 -- No warnings for expression functions
3893 and then Nkind (Original_Node (N)) /= N_Expression_Function
3895 Style.Body_With_No_Spec (N);
3898 New_Overloaded_Entity (Body_Id);
3900 if Nkind (N) /= N_Subprogram_Body_Stub then
3901 Set_Acts_As_Spec (N);
3902 Generate_Definition (Body_Id);
3904 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3906 -- If the body is an entry wrapper created for an entry with
3907 -- preconditions, it must be compiled in the context of the
3908 -- enclosing synchronized object, because it may mention other
3909 -- operations of the type.
3911 if Is_Entry_Wrapper (Body_Id) then
3913 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3916 Install_Declarations (Prot);
3920 Install_Formals (Body_Id);
3922 Push_Scope (Body_Id);
3925 -- For stubs and bodies with no previous spec, generate references to
3928 Generate_Reference_To_Formals (Body_Id);
3931 -- Entry barrier functions are generated outside the protected type and
3932 -- should not carry the SPARK_Mode of the enclosing context.
3934 if Nkind (N) = N_Subprogram_Body
3935 and then Is_Entry_Barrier_Function (N)
3939 -- The body is generated as part of expression function expansion. When
3940 -- the expression function appears in the visible declarations of a
3941 -- package, the body is added to the private declarations. Since both
3942 -- declarative lists may be subject to a different SPARK_Mode, inherit
3943 -- the mode of the spec.
3945 -- package P with SPARK_Mode is
3946 -- function Expr_Func ... is (...); -- original
3947 -- [function Expr_Func ...;] -- generated spec
3950 -- pragma SPARK_Mode (Off);
3951 -- [function Expr_Func ... is return ...;] -- generated body
3952 -- end P; -- mode is ON
3954 elsif not Comes_From_Source (N)
3955 and then Present (Spec_Id)
3956 and then Is_Expression_Function (Spec_Id)
3958 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
3959 Set_SPARK_Pragma_Inherited
3960 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
3962 -- Set the SPARK_Mode from the current context (may be overwritten later
3963 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
3964 -- initially on a stand-alone subprogram body, but is then relocated to
3965 -- a generated corresponding spec. In this scenario the mode is shared
3966 -- between the spec and body.
3968 elsif No (SPARK_Pragma (Body_Id)) then
3969 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
3970 Set_SPARK_Pragma_Inherited (Body_Id);
3973 -- A subprogram body may be instantiated or inlined at a later pass.
3974 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
3975 -- applied to the initial declaration of the body.
3977 if Present (Spec_Id) then
3978 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
3979 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
3983 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
3984 -- case the body is instantiated or inlined later and out of context.
3985 -- The body uses this attribute to restore the value of the global
3988 if Ignore_SPARK_Mode_Pragmas_In_Instance then
3989 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
3991 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
3992 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
3996 -- Preserve relevant elaboration-related attributes of the context which
3997 -- are no longer available or very expensive to recompute once analysis,
3998 -- resolution, and expansion are over.
4000 if No (Spec_Id) then
4001 Mark_Elaboration_Attributes
4007 -- If this is the proper body of a stub, we must verify that the stub
4008 -- conforms to the body, and to the previous spec if one was present.
4009 -- We know already that the body conforms to that spec. This test is
4010 -- only required for subprograms that come from source.
4012 if Nkind (Parent (N)) = N_Subunit
4013 and then Comes_From_Source (N)
4014 and then not Error_Posted (Body_Id)
4015 and then Nkind (Corresponding_Stub (Parent (N))) =
4016 N_Subprogram_Body_Stub
4019 Old_Id : constant Entity_Id :=
4021 (Specification (Corresponding_Stub (Parent (N))));
4023 Conformant : Boolean := False;
4026 if No (Spec_Id) then
4027 Check_Fully_Conformant (Body_Id, Old_Id);
4031 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4033 if not Conformant then
4035 -- The stub was taken to be a new declaration. Indicate that
4038 Set_Has_Completion (Old_Id, False);
4044 Set_Has_Completion (Body_Id);
4045 Check_Eliminated (Body_Id);
4047 -- Analyze any aspect specifications that appear on the subprogram body
4048 -- stub. Stop the analysis now as the stub does not have a declarative
4049 -- or a statement part, and it cannot be inlined.
4051 if Nkind (N) = N_Subprogram_Body_Stub then
4052 if Has_Aspects (N) then
4053 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4061 -- Note: Normally we don't do any inlining if expansion is off, since
4062 -- we won't generate code in any case. An exception arises in GNATprove
4063 -- mode where we want to expand some calls in place, even with expansion
4064 -- disabled, since the inlining eases formal verification.
4066 if not GNATprove_Mode
4067 and then Expander_Active
4068 and then Serious_Errors_Detected = 0
4069 and then Present (Spec_Id)
4070 and then Has_Pragma_Inline (Spec_Id)
4072 -- Legacy implementation (relying on front-end inlining)
4074 if not Back_End_Inlining then
4075 if (Has_Pragma_Inline_Always (Spec_Id)
4076 and then not Opt.Disable_FE_Inline_Always)
4077 or else (Front_End_Inlining
4078 and then not Opt.Disable_FE_Inline)
4080 Build_Body_To_Inline (N, Spec_Id);
4083 -- New implementation (relying on back-end inlining)
4086 if Has_Pragma_Inline_Always (Spec_Id)
4087 or else Optimization_Level > 0
4089 -- Handle function returning an unconstrained type
4091 if Comes_From_Source (Body_Id)
4092 and then Ekind (Spec_Id) = E_Function
4093 and then Returns_Unconstrained_Type (Spec_Id)
4095 -- If function builds in place, i.e. returns a limited type,
4096 -- inlining cannot be done.
4098 and then not Is_Limited_Type (Etype (Spec_Id))
4100 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4104 Subp_Body : constant Node_Id :=
4105 Unit_Declaration_Node (Body_Id);
4106 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4109 -- Do not pass inlining to the backend if the subprogram
4110 -- has declarations or statements which cannot be inlined
4111 -- by the backend. This check is done here to emit an
4112 -- error instead of the generic warning message reported
4113 -- by the GCC backend (ie. "function might not be
4116 if Present (Subp_Decl)
4117 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4121 elsif Has_Excluded_Statement
4124 (Handled_Statement_Sequence (Subp_Body)))
4128 -- If the backend inlining is available then at this
4129 -- stage we only have to mark the subprogram as inlined.
4130 -- The expander will take care of registering it in the
4131 -- table of subprograms inlined by the backend a part of
4132 -- processing calls to it (cf. Expand_Call)
4135 Set_Is_Inlined (Spec_Id);
4142 -- In GNATprove mode, inline only when there is a separate subprogram
4143 -- declaration for now, as inlining of subprogram bodies acting as
4144 -- declarations, or subprogram stubs, are not supported by front-end
4145 -- inlining. This inlining should occur after analysis of the body, so
4146 -- that it is known whether the value of SPARK_Mode, which can be
4147 -- defined by a pragma inside the body, is applicable to the body.
4148 -- Inlining can be disabled with switch -gnatdm
4150 elsif GNATprove_Mode
4151 and then Full_Analysis
4152 and then not Inside_A_Generic
4153 and then Present (Spec_Id)
4155 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4156 and then Body_Has_SPARK_Mode_On
4157 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4158 and then not Body_Has_Contract
4159 and then not Debug_Flag_M
4161 Build_Body_To_Inline (N, Spec_Id);
4164 -- When generating code, inherited pre/postconditions are handled when
4165 -- expanding the corresponding contract.
4167 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4168 -- of the specification we have to install the private withed units.
4169 -- This holds for child units as well.
4171 if Is_Compilation_Unit (Body_Id)
4172 or else Nkind (Parent (N)) = N_Compilation_Unit
4174 Install_Private_With_Clauses (Body_Id);
4177 Check_Anonymous_Return;
4179 -- Set the Protected_Formal field of each extra formal of the protected
4180 -- subprogram to reference the corresponding extra formal of the
4181 -- subprogram that implements it. For regular formals this occurs when
4182 -- the protected subprogram's declaration is expanded, but the extra
4183 -- formals don't get created until the subprogram is frozen. We need to
4184 -- do this before analyzing the protected subprogram's body so that any
4185 -- references to the original subprogram's extra formals will be changed
4186 -- refer to the implementing subprogram's formals (see Expand_Formal).
4188 if Present (Spec_Id)
4189 and then Is_Protected_Type (Scope (Spec_Id))
4190 and then Present (Protected_Body_Subprogram (Spec_Id))
4193 Impl_Subp : constant Entity_Id :=
4194 Protected_Body_Subprogram (Spec_Id);
4195 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4196 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4199 while Present (Prot_Ext_Formal) loop
4200 pragma Assert (Present (Impl_Ext_Formal));
4201 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4202 Next_Formal_With_Extras (Prot_Ext_Formal);
4203 Next_Formal_With_Extras (Impl_Ext_Formal);
4208 -- Now we can go on to analyze the body
4210 HSS := Handled_Statement_Sequence (N);
4211 Set_Actual_Subtypes (N, Current_Scope);
4213 -- Add a declaration for the Protection object, renaming declarations
4214 -- for discriminals and privals and finally a declaration for the entry
4215 -- family index (if applicable). This form of early expansion is done
4216 -- when the Expander is active because Install_Private_Data_Declarations
4217 -- references entities which were created during regular expansion. The
4218 -- subprogram entity must come from source, and not be an internally
4219 -- generated subprogram.
4222 and then Present (Prot_Typ)
4223 and then Present (Spec_Id)
4224 and then Comes_From_Source (Spec_Id)
4225 and then not Is_Eliminated (Spec_Id)
4227 Install_Private_Data_Declarations
4228 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4231 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4232 -- may now appear in parameter and result profiles. Since the analysis
4233 -- of a subprogram body may use the parameter and result profile of the
4234 -- spec, swap any limited views with their non-limited counterpart.
4236 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4237 Exch_Views := Exchange_Limited_Views (Spec_Id);
4240 -- If the return type is an anonymous access type whose designated type
4241 -- is the limited view of a class-wide type and the non-limited view is
4242 -- available, update the return type accordingly.
4244 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4250 Rtyp := Etype (Spec_Id);
4252 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4253 Etyp := Directly_Designated_Type (Rtyp);
4255 if Is_Class_Wide_Type (Etyp)
4256 and then From_Limited_With (Etyp)
4259 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4265 -- Analyze any aspect specifications that appear on the subprogram body
4267 if Has_Aspects (N) then
4268 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4271 Analyze_Declarations (Declarations (N));
4273 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4275 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4276 if Present (SPARK_Pragma (Spec_Id)) then
4277 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4279 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4281 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4282 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4283 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4285 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4288 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4292 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4293 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4294 Error_Msg_Sloc := Sloc (Spec_Id);
4296 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4300 -- A subprogram body freezes its own contract. Analyze the contract
4301 -- after the declarations of the body have been processed as pragmas
4302 -- are now chained on the contract of the subprogram body.
4304 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4306 -- Check completion, and analyze the statements
4309 Inspect_Deferred_Constant_Completion (Declarations (N));
4312 -- Deal with end of scope processing for the body
4314 Process_End_Label (HSS, 't', Current_Scope);
4315 Update_Use_Clause_Chain;
4318 -- If we are compiling an entry wrapper, remove the enclosing
4319 -- synchronized object from the stack.
4321 if Is_Entry_Wrapper (Body_Id) then
4325 Check_Subprogram_Order (N);
4326 Set_Analyzed (Body_Id);
4328 -- If we have a separate spec, then the analysis of the declarations
4329 -- caused the entities in the body to be chained to the spec id, but
4330 -- we want them chained to the body id. Only the formal parameters
4331 -- end up chained to the spec id in this case.
4333 if Present (Spec_Id) then
4335 -- We must conform to the categorization of our spec
4337 Validate_Categorization_Dependency (N, Spec_Id);
4339 -- And if this is a child unit, the parent units must conform
4341 if Is_Child_Unit (Spec_Id) then
4342 Validate_Categorization_Dependency
4343 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4346 -- Here is where we move entities from the spec to the body
4348 -- Case where there are entities that stay with the spec
4350 if Present (Last_Real_Spec_Entity) then
4352 -- No body entities (happens when the only real spec entities come
4353 -- from precondition and postcondition pragmas).
4355 if No (Last_Entity (Body_Id)) then
4356 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4358 -- Body entities present (formals), so chain stuff past them
4362 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4365 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4366 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4367 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4369 -- Case where there are no spec entities, in this case there can be
4370 -- no body entities either, so just move everything.
4372 -- If the body is generated for an expression function, it may have
4373 -- been preanalyzed already, if 'access was applied to it.
4376 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4377 N_Expression_Function
4379 pragma Assert (No (Last_Entity (Body_Id)));
4383 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4384 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4385 Set_First_Entity (Spec_Id, Empty);
4386 Set_Last_Entity (Spec_Id, Empty);
4389 -- Otherwise the body does not complete a previous declaration. Check
4390 -- the categorization of the body against the units it withs.
4393 Validate_Categorization_Dependency (N, Body_Id);
4396 Check_Missing_Return;
4398 -- Now we are going to check for variables that are never modified in
4399 -- the body of the procedure. But first we deal with a special case
4400 -- where we want to modify this check. If the body of the subprogram
4401 -- starts with a raise statement or its equivalent, or if the body
4402 -- consists entirely of a null statement, then it is pretty obvious that
4403 -- it is OK to not reference the parameters. For example, this might be
4404 -- the following common idiom for a stubbed function: statement of the
4405 -- procedure raises an exception. In particular this deals with the
4406 -- common idiom of a stubbed function, which appears something like:
4408 -- function F (A : Integer) return Some_Type;
4411 -- raise Program_Error;
4415 -- Here the purpose of X is simply to satisfy the annoying requirement
4416 -- in Ada that there be at least one return, and we certainly do not
4417 -- want to go posting warnings on X that it is not initialized. On
4418 -- the other hand, if X is entirely unreferenced that should still
4421 -- What we do is to detect these cases, and if we find them, flag the
4422 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4423 -- suppress unwanted warnings. For the case of the function stub above
4424 -- we have a special test to set X as apparently assigned to suppress
4431 -- Skip call markers installed by the ABE mechanism, labels, and
4432 -- Push_xxx_Error_Label to find the first real statement.
4434 Stm := First (Statements (HSS));
4435 while Nkind_In (Stm, N_Call_Marker, N_Label)
4436 or else Nkind (Stm) in N_Push_xxx_Label
4441 -- Do the test on the original statement before expansion
4444 Ostm : constant Node_Id := Original_Node (Stm);
4447 -- If explicit raise statement, turn on flag
4449 if Nkind (Ostm) = N_Raise_Statement then
4450 Set_Trivial_Subprogram (Stm);
4452 -- If null statement, and no following statements, turn on flag
4454 elsif Nkind (Stm) = N_Null_Statement
4455 and then Comes_From_Source (Stm)
4456 and then No (Next (Stm))
4458 Set_Trivial_Subprogram (Stm);
4460 -- Check for explicit call cases which likely raise an exception
4462 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4463 if Is_Entity_Name (Name (Ostm)) then
4465 Ent : constant Entity_Id := Entity (Name (Ostm));
4468 -- If the procedure is marked No_Return, then likely it
4469 -- raises an exception, but in any case it is not coming
4470 -- back here, so turn on the flag.
4473 and then Ekind (Ent) = E_Procedure
4474 and then No_Return (Ent)
4476 Set_Trivial_Subprogram (Stm);
4484 -- Check for variables that are never modified
4491 -- If there is a separate spec, then transfer Never_Set_In_Source
4492 -- flags from out parameters to the corresponding entities in the
4493 -- body. The reason we do that is we want to post error flags on
4494 -- the body entities, not the spec entities.
4496 if Present (Spec_Id) then
4497 E1 := First_Entity (Spec_Id);
4498 while Present (E1) loop
4499 if Ekind (E1) = E_Out_Parameter then
4500 E2 := First_Entity (Body_Id);
4501 while Present (E2) loop
4502 exit when Chars (E1) = Chars (E2);
4506 if Present (E2) then
4507 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4515 -- Check references of the subprogram spec when we are dealing with
4516 -- an expression function due to it having a generated body.
4517 -- Otherwise, we simply check the formals of the subprogram body.
4519 if Present (Spec_Id)
4520 and then Is_Expression_Function (Spec_Id)
4522 Check_References (Spec_Id);
4524 Check_References (Body_Id);
4528 -- Check for nested subprogram, and mark outer level subprogram if so
4534 if Present (Spec_Id) then
4541 Ent := Enclosing_Subprogram (Ent);
4542 exit when No (Ent) or else Is_Subprogram (Ent);
4545 if Present (Ent) then
4546 Set_Has_Nested_Subprogram (Ent);
4550 -- Restore the limited views in the spec, if any, to let the back end
4551 -- process it without running into circularities.
4553 if Exch_Views /= No_Elist then
4554 Restore_Limited_Views (Exch_Views);
4557 if Mask_Types /= No_Elist then
4558 Unmask_Unfrozen_Types (Mask_Types);
4561 if Present (Desig_View) then
4562 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4566 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4567 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4568 end Analyze_Subprogram_Body_Helper;
4570 ------------------------------------
4571 -- Analyze_Subprogram_Declaration --
4572 ------------------------------------
4574 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4575 Scop : constant Entity_Id := Current_Scope;
4576 Designator : Entity_Id;
4578 Is_Completion : Boolean;
4579 -- Indicates whether a null procedure declaration is a completion
4582 -- Null procedures are not allowed in SPARK
4584 if Nkind (Specification (N)) = N_Procedure_Specification
4585 and then Null_Present (Specification (N))
4587 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4589 -- Null procedures are allowed in protected types, following the
4590 -- recent AI12-0147.
4592 if Is_Protected_Type (Current_Scope)
4593 and then Ada_Version < Ada_2012
4595 Error_Msg_N ("protected operation cannot be a null procedure", N);
4598 Analyze_Null_Procedure (N, Is_Completion);
4600 -- The null procedure acts as a body, nothing further is needed
4602 if Is_Completion then
4607 Designator := Analyze_Subprogram_Specification (Specification (N));
4609 -- A reference may already have been generated for the unit name, in
4610 -- which case the following call is redundant. However it is needed for
4611 -- declarations that are the rewriting of an expression function.
4613 Generate_Definition (Designator);
4615 -- Set the SPARK mode from the current context (may be overwritten later
4616 -- with explicit pragma). This is not done for entry barrier functions
4617 -- because they are generated outside the protected type and should not
4618 -- carry the mode of the enclosing context.
4620 if Nkind (N) = N_Subprogram_Declaration
4621 and then Is_Entry_Barrier_Function (N)
4626 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4627 Set_SPARK_Pragma_Inherited (Designator);
4630 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4631 -- the body of this subprogram is instantiated or inlined later and out
4632 -- of context. The body uses this attribute to restore the value of the
4635 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4636 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4639 -- Preserve relevant elaboration-related attributes of the context which
4640 -- are no longer available or very expensive to recompute once analysis,
4641 -- resolution, and expansion are over.
4643 Mark_Elaboration_Attributes
4644 (N_Id => Designator,
4648 if Debug_Flag_C then
4649 Write_Str ("==> subprogram spec ");
4650 Write_Name (Chars (Designator));
4651 Write_Str (" from ");
4652 Write_Location (Sloc (N));
4657 Validate_RCI_Subprogram_Declaration (N);
4658 New_Overloaded_Entity (Designator);
4659 Check_Delayed_Subprogram (Designator);
4661 -- If the type of the first formal of the current subprogram is a non-
4662 -- generic tagged private type, mark the subprogram as being a private
4663 -- primitive. Ditto if this is a function with controlling result, and
4664 -- the return type is currently private. In both cases, the type of the
4665 -- controlling argument or result must be in the current scope for the
4666 -- operation to be primitive.
4668 if Has_Controlling_Result (Designator)
4669 and then Is_Private_Type (Etype (Designator))
4670 and then Scope (Etype (Designator)) = Current_Scope
4671 and then not Is_Generic_Actual_Type (Etype (Designator))
4673 Set_Is_Private_Primitive (Designator);
4675 elsif Present (First_Formal (Designator)) then
4677 Formal_Typ : constant Entity_Id :=
4678 Etype (First_Formal (Designator));
4680 Set_Is_Private_Primitive (Designator,
4681 Is_Tagged_Type (Formal_Typ)
4682 and then Scope (Formal_Typ) = Current_Scope
4683 and then Is_Private_Type (Formal_Typ)
4684 and then not Is_Generic_Actual_Type (Formal_Typ));
4688 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4691 if Ada_Version >= Ada_2005
4692 and then Comes_From_Source (N)
4693 and then Is_Dispatching_Operation (Designator)
4700 if Has_Controlling_Result (Designator) then
4701 Etyp := Etype (Designator);
4704 E := First_Entity (Designator);
4706 and then Is_Formal (E)
4707 and then not Is_Controlling_Formal (E)
4715 if Is_Access_Type (Etyp) then
4716 Etyp := Directly_Designated_Type (Etyp);
4719 if Is_Interface (Etyp)
4720 and then not Is_Abstract_Subprogram (Designator)
4721 and then not (Ekind (Designator) = E_Procedure
4722 and then Null_Present (Specification (N)))
4724 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4726 -- Specialize error message based on procedures vs. functions,
4727 -- since functions can't be null subprograms.
4729 if Ekind (Designator) = E_Procedure then
4731 ("interface procedure % must be abstract or null", N);
4734 ("interface function % must be abstract", N);
4740 -- What is the following code for, it used to be
4742 -- ??? Set_Suppress_Elaboration_Checks
4743 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4745 -- The following seems equivalent, but a bit dubious
4747 if Elaboration_Checks_Suppressed (Designator) then
4748 Set_Kill_Elaboration_Checks (Designator);
4751 -- For a compilation unit, set body required. This flag will only be
4752 -- reset if a valid Import or Interface pragma is processed later on.
4754 if Nkind (Parent (N)) = N_Compilation_Unit then
4755 Set_Body_Required (Parent (N), True);
4757 if Ada_Version >= Ada_2005
4758 and then Nkind (Specification (N)) = N_Procedure_Specification
4759 and then Null_Present (Specification (N))
4762 ("null procedure cannot be declared at library level", N);
4766 Generate_Reference_To_Formals (Designator);
4767 Check_Eliminated (Designator);
4769 if Debug_Flag_C then
4771 Write_Str ("<== subprogram spec ");
4772 Write_Name (Chars (Designator));
4773 Write_Str (" from ");
4774 Write_Location (Sloc (N));
4778 -- Indicate that this is a protected operation, because it may be used
4779 -- in subsequent declarations within the protected type.
4781 if Is_Protected_Type (Current_Scope) then
4782 Set_Convention (Designator, Convention_Protected);
4785 List_Inherited_Pre_Post_Aspects (Designator);
4787 -- Process the aspects before establishing the proper categorization in
4788 -- case the subprogram is a compilation unit and one of its aspects is
4789 -- converted into a categorization pragma.
4791 if Has_Aspects (N) then
4792 Analyze_Aspect_Specifications (N, Designator);
4795 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4796 Set_Categorization_From_Scope (Designator, Scop);
4798 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4799 -- proper categorization of the unit based on its pragmas.
4802 Push_Scope (Designator);
4803 Set_Categorization_From_Pragmas (N);
4804 Validate_Categorization_Dependency (N, Designator);
4807 end Analyze_Subprogram_Declaration;
4809 --------------------------------------
4810 -- Analyze_Subprogram_Specification --
4811 --------------------------------------
4813 -- Reminder: N here really is a subprogram specification (not a subprogram
4814 -- declaration). This procedure is called to analyze the specification in
4815 -- both subprogram bodies and subprogram declarations (specs).
4817 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4818 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4819 -- Determine whether entity E denotes the spec or body of an invariant
4822 ------------------------------------
4823 -- Is_Invariant_Procedure_Or_Body --
4824 ------------------------------------
4826 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4827 Decl : constant Node_Id := Unit_Declaration_Node (E);
4831 if Nkind (Decl) = N_Subprogram_Body then
4832 Spec := Corresponding_Spec (Decl);
4839 and then Ekind (Spec) = E_Procedure
4840 and then (Is_Partial_Invariant_Procedure (Spec)
4841 or else Is_Invariant_Procedure (Spec));
4842 end Is_Invariant_Procedure_Or_Body;
4846 Designator : constant Entity_Id := Defining_Entity (N);
4847 Formals : constant List_Id := Parameter_Specifications (N);
4849 -- Start of processing for Analyze_Subprogram_Specification
4852 -- User-defined operator is not allowed in SPARK, except as a renaming
4854 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4855 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4857 Check_SPARK_05_Restriction
4858 ("user-defined operator is not allowed", N);
4861 -- Proceed with analysis. Do not emit a cross-reference entry if the
4862 -- specification comes from an expression function, because it may be
4863 -- the completion of a previous declaration. If it is not, the cross-
4864 -- reference entry will be emitted for the new subprogram declaration.
4866 if Nkind (Parent (N)) /= N_Expression_Function then
4867 Generate_Definition (Designator);
4870 if Nkind (N) = N_Function_Specification then
4871 Set_Ekind (Designator, E_Function);
4872 Set_Mechanism (Designator, Default_Mechanism);
4874 Set_Ekind (Designator, E_Procedure);
4875 Set_Etype (Designator, Standard_Void_Type);
4878 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4879 -- those subprograms which could be inlined in GNATprove mode (because
4880 -- Body_To_Inline is non-Empty) but should not be inlined.
4882 if GNATprove_Mode then
4883 Set_Is_Inlined_Always (Designator);
4886 -- Introduce new scope for analysis of the formals and the return type
4888 Set_Scope (Designator, Current_Scope);
4890 if Present (Formals) then
4891 Push_Scope (Designator);
4892 Process_Formals (Formals, N);
4894 -- Check dimensions in N for formals with default expression
4896 Analyze_Dimension_Formals (N, Formals);
4898 -- Ada 2005 (AI-345): If this is an overriding operation of an
4899 -- inherited interface operation, and the controlling type is
4900 -- a synchronized type, replace the type with its corresponding
4901 -- record, to match the proper signature of an overriding operation.
4902 -- Same processing for an access parameter whose designated type is
4903 -- derived from a synchronized interface.
4905 -- This modification is not done for invariant procedures because
4906 -- the corresponding record may not necessarely be visible when the
4907 -- concurrent type acts as the full view of a private type.
4910 -- type Prot is private with Type_Invariant => ...;
4911 -- procedure ConcInvariant (Obj : Prot);
4913 -- protected type Prot is ...;
4914 -- type Concurrent_Record_Prot is record ...;
4915 -- procedure ConcInvariant (Obj : Prot) is
4917 -- end ConcInvariant;
4920 -- In the example above, both the spec and body of the invariant
4921 -- procedure must utilize the private type as the controlling type.
4923 if Ada_Version >= Ada_2005
4924 and then not Is_Invariant_Procedure_Or_Body (Designator)
4928 Formal_Typ : Entity_Id;
4929 Rec_Typ : Entity_Id;
4930 Desig_Typ : Entity_Id;
4933 Formal := First_Formal (Designator);
4934 while Present (Formal) loop
4935 Formal_Typ := Etype (Formal);
4937 if Is_Concurrent_Type (Formal_Typ)
4938 and then Present (Corresponding_Record_Type (Formal_Typ))
4940 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4942 if Present (Interfaces (Rec_Typ)) then
4943 Set_Etype (Formal, Rec_Typ);
4946 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4947 Desig_Typ := Designated_Type (Formal_Typ);
4949 if Is_Concurrent_Type (Desig_Typ)
4950 and then Present (Corresponding_Record_Type (Desig_Typ))
4952 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4954 if Present (Interfaces (Rec_Typ)) then
4955 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
4960 Next_Formal (Formal);
4967 -- The subprogram scope is pushed and popped around the processing of
4968 -- the return type for consistency with call above to Process_Formals
4969 -- (which itself can call Analyze_Return_Type), and to ensure that any
4970 -- itype created for the return type will be associated with the proper
4973 elsif Nkind (N) = N_Function_Specification then
4974 Push_Scope (Designator);
4975 Analyze_Return_Type (N);
4981 if Nkind (N) = N_Function_Specification then
4983 -- Deal with operator symbol case
4985 if Nkind (Designator) = N_Defining_Operator_Symbol then
4986 Valid_Operator_Definition (Designator);
4989 May_Need_Actuals (Designator);
4991 -- Ada 2005 (AI-251): If the return type is abstract, verify that
4992 -- the subprogram is abstract also. This does not apply to renaming
4993 -- declarations, where abstractness is inherited, and to subprogram
4994 -- bodies generated for stream operations, which become renamings as
4997 -- In case of primitives associated with abstract interface types
4998 -- the check is applied later (see Analyze_Subprogram_Declaration).
5000 if not Nkind_In (Original_Node (Parent (N)),
5001 N_Abstract_Subprogram_Declaration,
5002 N_Formal_Abstract_Subprogram_Declaration,
5003 N_Subprogram_Renaming_Declaration)
5005 if Is_Abstract_Type (Etype (Designator))
5006 and then not Is_Interface (Etype (Designator))
5009 ("function that returns abstract type must be abstract", N);
5011 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5012 -- access result whose designated type is abstract.
5014 elsif Ada_Version >= Ada_2012
5015 and then Nkind (Result_Definition (N)) = N_Access_Definition
5017 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5018 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5021 ("function whose access result designates abstract type "
5022 & "must be abstract", N);
5028 end Analyze_Subprogram_Specification;
5030 -----------------------
5031 -- Check_Conformance --
5032 -----------------------
5034 procedure Check_Conformance
5035 (New_Id : Entity_Id;
5037 Ctype : Conformance_Type;
5039 Conforms : out Boolean;
5040 Err_Loc : Node_Id := Empty;
5041 Get_Inst : Boolean := False;
5042 Skip_Controlling_Formals : Boolean := False)
5044 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5045 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5046 -- If Errmsg is True, then processing continues to post an error message
5047 -- for conformance error on given node. Two messages are output. The
5048 -- first message points to the previous declaration with a general "no
5049 -- conformance" message. The second is the detailed reason, supplied as
5050 -- Msg. The parameter N provide information for a possible & insertion
5051 -- in the message, and also provides the location for posting the
5052 -- message in the absence of a specified Err_Loc location.
5054 function Conventions_Match
5056 Id2 : Entity_Id) return Boolean;
5057 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5060 -----------------------
5061 -- Conformance_Error --
5062 -----------------------
5064 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5071 if No (Err_Loc) then
5077 Error_Msg_Sloc := Sloc (Old_Id);
5080 when Type_Conformant =>
5081 Error_Msg_N -- CODEFIX
5082 ("not type conformant with declaration#!", Enode);
5084 when Mode_Conformant =>
5085 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5087 ("not mode conformant with operation inherited#!",
5091 ("not mode conformant with declaration#!", Enode);
5094 when Subtype_Conformant =>
5095 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5097 ("not subtype conformant with operation inherited#!",
5101 ("not subtype conformant with declaration#!", Enode);
5104 when Fully_Conformant =>
5105 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5106 Error_Msg_N -- CODEFIX
5107 ("not fully conformant with operation inherited#!",
5110 Error_Msg_N -- CODEFIX
5111 ("not fully conformant with declaration#!", Enode);
5115 Error_Msg_NE (Msg, Enode, N);
5117 end Conformance_Error;
5119 -----------------------
5120 -- Conventions_Match --
5121 -----------------------
5123 function Conventions_Match
5125 Id2 : Entity_Id) return Boolean
5128 -- Ignore the conventions of anonymous access-to-subprogram types
5129 -- and subprogram types because these are internally generated and
5130 -- the only way these may receive a convention is if they inherit
5131 -- the convention of a related subprogram.
5133 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5136 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5141 -- Otherwise compare the conventions directly
5144 return Convention (Id1) = Convention (Id2);
5146 end Conventions_Match;
5150 Old_Type : constant Entity_Id := Etype (Old_Id);
5151 New_Type : constant Entity_Id := Etype (New_Id);
5152 Old_Formal : Entity_Id;
5153 New_Formal : Entity_Id;
5154 Access_Types_Match : Boolean;
5155 Old_Formal_Base : Entity_Id;
5156 New_Formal_Base : Entity_Id;
5158 -- Start of processing for Check_Conformance
5163 -- We need a special case for operators, since they don't appear
5166 if Ctype = Type_Conformant then
5167 if Ekind (New_Id) = E_Operator
5168 and then Operator_Matches_Spec (New_Id, Old_Id)
5174 -- If both are functions/operators, check return types conform
5176 if Old_Type /= Standard_Void_Type
5178 New_Type /= Standard_Void_Type
5180 -- If we are checking interface conformance we omit controlling
5181 -- arguments and result, because we are only checking the conformance
5182 -- of the remaining parameters.
5184 if Has_Controlling_Result (Old_Id)
5185 and then Has_Controlling_Result (New_Id)
5186 and then Skip_Controlling_Formals
5190 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5191 if Ctype >= Subtype_Conformant
5192 and then not Predicates_Match (Old_Type, New_Type)
5195 ("\predicate of return type does not match!", New_Id);
5198 ("\return type does not match!", New_Id);
5204 -- Ada 2005 (AI-231): In case of anonymous access types check the
5205 -- null-exclusion and access-to-constant attributes match.
5207 if Ada_Version >= Ada_2005
5208 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5210 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5211 or else Is_Access_Constant (Etype (Old_Type)) /=
5212 Is_Access_Constant (Etype (New_Type)))
5214 Conformance_Error ("\return type does not match!", New_Id);
5218 -- If either is a function/operator and the other isn't, error
5220 elsif Old_Type /= Standard_Void_Type
5221 or else New_Type /= Standard_Void_Type
5223 Conformance_Error ("\functions can only match functions!", New_Id);
5227 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5228 -- If this is a renaming as body, refine error message to indicate that
5229 -- the conflict is with the original declaration. If the entity is not
5230 -- frozen, the conventions don't have to match, the one of the renamed
5231 -- entity is inherited.
5233 if Ctype >= Subtype_Conformant then
5234 if not Conventions_Match (Old_Id, New_Id) then
5235 if not Is_Frozen (New_Id) then
5238 elsif Present (Err_Loc)
5239 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5240 and then Present (Corresponding_Spec (Err_Loc))
5242 Error_Msg_Name_1 := Chars (New_Id);
5244 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5245 Conformance_Error ("\prior declaration for% has convention %!");
5248 Conformance_Error ("\calling conventions do not match!");
5253 elsif Is_Formal_Subprogram (Old_Id)
5254 or else Is_Formal_Subprogram (New_Id)
5255 or else (Is_Subprogram (New_Id)
5256 and then Present (Alias (New_Id))
5257 and then Is_Formal_Subprogram (Alias (New_Id)))
5260 ("\formal subprograms are not subtype conformant "
5261 & "(RM 6.3.1 (17/3))");
5265 -- Deal with parameters
5267 -- Note: we use the entity information, rather than going directly
5268 -- to the specification in the tree. This is not only simpler, but
5269 -- absolutely necessary for some cases of conformance tests between
5270 -- operators, where the declaration tree simply does not exist.
5272 Old_Formal := First_Formal (Old_Id);
5273 New_Formal := First_Formal (New_Id);
5274 while Present (Old_Formal) and then Present (New_Formal) loop
5275 if Is_Controlling_Formal (Old_Formal)
5276 and then Is_Controlling_Formal (New_Formal)
5277 and then Skip_Controlling_Formals
5279 -- The controlling formals will have different types when
5280 -- comparing an interface operation with its match, but both
5281 -- or neither must be access parameters.
5283 if Is_Access_Type (Etype (Old_Formal))
5285 Is_Access_Type (Etype (New_Formal))
5287 goto Skip_Controlling_Formal;
5290 ("\access parameter does not match!", New_Formal);
5294 -- Ada 2012: Mode conformance also requires that formal parameters
5295 -- be both aliased, or neither.
5297 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5298 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5300 ("\aliased parameter mismatch!", New_Formal);
5304 if Ctype = Fully_Conformant then
5306 -- Names must match. Error message is more accurate if we do
5307 -- this before checking that the types of the formals match.
5309 if Chars (Old_Formal) /= Chars (New_Formal) then
5310 Conformance_Error ("\name& does not match!", New_Formal);
5312 -- Set error posted flag on new formal as well to stop
5313 -- junk cascaded messages in some cases.
5315 Set_Error_Posted (New_Formal);
5319 -- Null exclusion must match
5321 if Null_Exclusion_Present (Parent (Old_Formal))
5323 Null_Exclusion_Present (Parent (New_Formal))
5325 -- Only give error if both come from source. This should be
5326 -- investigated some time, since it should not be needed ???
5328 if Comes_From_Source (Old_Formal)
5330 Comes_From_Source (New_Formal)
5333 ("\null exclusion for& does not match", New_Formal);
5335 -- Mark error posted on the new formal to avoid duplicated
5336 -- complaint about types not matching.
5338 Set_Error_Posted (New_Formal);
5343 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5344 -- case occurs whenever a subprogram is being renamed and one of its
5345 -- parameters imposes a null exclusion. For example:
5347 -- type T is null record;
5348 -- type Acc_T is access T;
5349 -- subtype Acc_T_Sub is Acc_T;
5351 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5352 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5355 Old_Formal_Base := Etype (Old_Formal);
5356 New_Formal_Base := Etype (New_Formal);
5359 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5360 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5363 Access_Types_Match := Ada_Version >= Ada_2005
5365 -- Ensure that this rule is only applied when New_Id is a
5366 -- renaming of Old_Id.
5368 and then Nkind (Parent (Parent (New_Id))) =
5369 N_Subprogram_Renaming_Declaration
5370 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5371 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5372 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5374 -- Now handle the allowed access-type case
5376 and then Is_Access_Type (Old_Formal_Base)
5377 and then Is_Access_Type (New_Formal_Base)
5379 -- The type kinds must match. The only exception occurs with
5380 -- multiple generics of the form:
5383 -- type F is private; type A is private;
5384 -- type F_Ptr is access F; type A_Ptr is access A;
5385 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5386 -- package F_Pack is ... package A_Pack is
5387 -- package F_Inst is
5388 -- new F_Pack (A, A_Ptr, A_P);
5390 -- When checking for conformance between the parameters of A_P
5391 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5392 -- because the compiler has transformed A_Ptr into a subtype of
5393 -- F_Ptr. We catch this case in the code below.
5395 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5397 (Is_Generic_Type (Old_Formal_Base)
5398 and then Is_Generic_Type (New_Formal_Base)
5399 and then Is_Internal (New_Formal_Base)
5400 and then Etype (Etype (New_Formal_Base)) =
5402 and then Directly_Designated_Type (Old_Formal_Base) =
5403 Directly_Designated_Type (New_Formal_Base)
5404 and then ((Is_Itype (Old_Formal_Base)
5405 and then Can_Never_Be_Null (Old_Formal_Base))
5407 (Is_Itype (New_Formal_Base)
5408 and then Can_Never_Be_Null (New_Formal_Base)));
5410 -- Types must always match. In the visible part of an instance,
5411 -- usual overloading rules for dispatching operations apply, and
5412 -- we check base types (not the actual subtypes).
5414 if In_Instance_Visible_Part
5415 and then Is_Dispatching_Operation (New_Id)
5417 if not Conforming_Types
5418 (T1 => Base_Type (Etype (Old_Formal)),
5419 T2 => Base_Type (Etype (New_Formal)),
5421 Get_Inst => Get_Inst)
5422 and then not Access_Types_Match
5424 Conformance_Error ("\type of & does not match!", New_Formal);
5428 elsif not Conforming_Types
5429 (T1 => Old_Formal_Base,
5430 T2 => New_Formal_Base,
5432 Get_Inst => Get_Inst)
5433 and then not Access_Types_Match
5435 -- Don't give error message if old type is Any_Type. This test
5436 -- avoids some cascaded errors, e.g. in case of a bad spec.
5438 if Errmsg and then Old_Formal_Base = Any_Type then
5441 if Ctype >= Subtype_Conformant
5443 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5446 ("\predicate of & does not match!", New_Formal);
5449 ("\type of & does not match!", New_Formal);
5451 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5453 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5461 -- For mode conformance, mode must match
5463 if Ctype >= Mode_Conformant then
5464 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5465 if not Ekind_In (New_Id, E_Function, E_Procedure)
5466 or else not Is_Primitive_Wrapper (New_Id)
5468 Conformance_Error ("\mode of & does not match!", New_Formal);
5472 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5474 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5476 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5479 ("\mode of & does not match!", New_Formal);
5486 -- Part of mode conformance for access types is having the same
5487 -- constant modifier.
5489 elsif Access_Types_Match
5490 and then Is_Access_Constant (Old_Formal_Base) /=
5491 Is_Access_Constant (New_Formal_Base)
5494 ("\constant modifier does not match!", New_Formal);
5499 if Ctype >= Subtype_Conformant then
5501 -- Ada 2005 (AI-231): In case of anonymous access types check
5502 -- the null-exclusion and access-to-constant attributes must
5503 -- match. For null exclusion, we test the types rather than the
5504 -- formals themselves, since the attribute is only set reliably
5505 -- on the formals in the Ada 95 case, and we exclude the case
5506 -- where Old_Formal is marked as controlling, to avoid errors
5507 -- when matching completing bodies with dispatching declarations
5508 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5510 if Ada_Version >= Ada_2005
5511 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5512 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5514 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5515 Can_Never_Be_Null (Etype (New_Formal))
5517 not Is_Controlling_Formal (Old_Formal))
5519 Is_Access_Constant (Etype (Old_Formal)) /=
5520 Is_Access_Constant (Etype (New_Formal)))
5522 -- Do not complain if error already posted on New_Formal. This
5523 -- avoids some redundant error messages.
5525 and then not Error_Posted (New_Formal)
5527 -- It is allowed to omit the null-exclusion in case of stream
5528 -- attribute subprograms. We recognize stream subprograms
5529 -- through their TSS-generated suffix.
5532 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5535 if TSS_Name /= TSS_Stream_Read
5536 and then TSS_Name /= TSS_Stream_Write
5537 and then TSS_Name /= TSS_Stream_Input
5538 and then TSS_Name /= TSS_Stream_Output
5540 -- Here we have a definite conformance error. It is worth
5541 -- special casing the error message for the case of a
5542 -- controlling formal (which excludes null).
5544 if Is_Controlling_Formal (New_Formal) then
5545 Error_Msg_Node_2 := Scope (New_Formal);
5547 ("\controlling formal & of & excludes null, "
5548 & "declaration must exclude null as well",
5551 -- Normal case (couldn't we give more detail here???)
5555 ("\type of & does not match!", New_Formal);
5564 -- Full conformance checks
5566 if Ctype = Fully_Conformant then
5568 -- We have checked already that names match
5570 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5572 -- Check default expressions for in parameters
5575 NewD : constant Boolean :=
5576 Present (Default_Value (New_Formal));
5577 OldD : constant Boolean :=
5578 Present (Default_Value (Old_Formal));
5580 if NewD or OldD then
5582 -- The old default value has been analyzed because the
5583 -- current full declaration will have frozen everything
5584 -- before. The new default value has not been analyzed,
5585 -- so analyze it now before we check for conformance.
5588 Push_Scope (New_Id);
5589 Preanalyze_Spec_Expression
5590 (Default_Value (New_Formal), Etype (New_Formal));
5594 if not (NewD and OldD)
5595 or else not Fully_Conformant_Expressions
5596 (Default_Value (Old_Formal),
5597 Default_Value (New_Formal))
5600 ("\default expression for & does not match!",
5609 -- A couple of special checks for Ada 83 mode. These checks are
5610 -- skipped if either entity is an operator in package Standard,
5611 -- or if either old or new instance is not from the source program.
5613 if Ada_Version = Ada_83
5614 and then Sloc (Old_Id) > Standard_Location
5615 and then Sloc (New_Id) > Standard_Location
5616 and then Comes_From_Source (Old_Id)
5617 and then Comes_From_Source (New_Id)
5620 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5621 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5624 -- Explicit IN must be present or absent in both cases. This
5625 -- test is required only in the full conformance case.
5627 if In_Present (Old_Param) /= In_Present (New_Param)
5628 and then Ctype = Fully_Conformant
5631 ("\(Ada 83) IN must appear in both declarations",
5636 -- Grouping (use of comma in param lists) must be the same
5637 -- This is where we catch a misconformance like:
5640 -- A : Integer; B : Integer
5642 -- which are represented identically in the tree except
5643 -- for the setting of the flags More_Ids and Prev_Ids.
5645 if More_Ids (Old_Param) /= More_Ids (New_Param)
5646 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5649 ("\grouping of & does not match!", New_Formal);
5655 -- This label is required when skipping controlling formals
5657 <<Skip_Controlling_Formal>>
5659 Next_Formal (Old_Formal);
5660 Next_Formal (New_Formal);
5663 if Present (Old_Formal) then
5664 Conformance_Error ("\too few parameters!");
5667 elsif Present (New_Formal) then
5668 Conformance_Error ("\too many parameters!", New_Formal);
5671 end Check_Conformance;
5673 -----------------------
5674 -- Check_Conventions --
5675 -----------------------
5677 procedure Check_Conventions (Typ : Entity_Id) is
5678 Ifaces_List : Elist_Id;
5680 procedure Check_Convention (Op : Entity_Id);
5681 -- Verify that the convention of inherited dispatching operation Op is
5682 -- consistent among all subprograms it overrides. In order to minimize
5683 -- the search, Search_From is utilized to designate a specific point in
5684 -- the list rather than iterating over the whole list once more.
5686 ----------------------
5687 -- Check_Convention --
5688 ----------------------
5690 procedure Check_Convention (Op : Entity_Id) is
5691 Op_Conv : constant Convention_Id := Convention (Op);
5692 Iface_Conv : Convention_Id;
5693 Iface_Elmt : Elmt_Id;
5694 Iface_Prim_Elmt : Elmt_Id;
5695 Iface_Prim : Entity_Id;
5698 Iface_Elmt := First_Elmt (Ifaces_List);
5699 while Present (Iface_Elmt) loop
5701 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5702 while Present (Iface_Prim_Elmt) loop
5703 Iface_Prim := Node (Iface_Prim_Elmt);
5704 Iface_Conv := Convention (Iface_Prim);
5706 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5707 and then Iface_Conv /= Op_Conv
5710 ("inconsistent conventions in primitive operations", Typ);
5712 Error_Msg_Name_1 := Chars (Op);
5713 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5714 Error_Msg_Sloc := Sloc (Op);
5716 if Comes_From_Source (Op) or else No (Alias (Op)) then
5717 if not Present (Overridden_Operation (Op)) then
5718 Error_Msg_N ("\\primitive % defined #", Typ);
5721 ("\\overriding operation % with "
5722 & "convention % defined #", Typ);
5725 else pragma Assert (Present (Alias (Op)));
5726 Error_Msg_Sloc := Sloc (Alias (Op));
5727 Error_Msg_N ("\\inherited operation % with "
5728 & "convention % defined #", Typ);
5731 Error_Msg_Name_1 := Chars (Op);
5732 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5733 Error_Msg_Sloc := Sloc (Iface_Prim);
5734 Error_Msg_N ("\\overridden operation % with "
5735 & "convention % defined #", Typ);
5737 -- Avoid cascading errors
5742 Next_Elmt (Iface_Prim_Elmt);
5745 Next_Elmt (Iface_Elmt);
5747 end Check_Convention;
5751 Prim_Op : Entity_Id;
5752 Prim_Op_Elmt : Elmt_Id;
5754 -- Start of processing for Check_Conventions
5757 if not Has_Interfaces (Typ) then
5761 Collect_Interfaces (Typ, Ifaces_List);
5763 -- The algorithm checks every overriding dispatching operation against
5764 -- all the corresponding overridden dispatching operations, detecting
5765 -- differences in conventions.
5767 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5768 while Present (Prim_Op_Elmt) loop
5769 Prim_Op := Node (Prim_Op_Elmt);
5771 -- A small optimization: skip the predefined dispatching operations
5772 -- since they always have the same convention.
5774 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5775 Check_Convention (Prim_Op);
5778 Next_Elmt (Prim_Op_Elmt);
5780 end Check_Conventions;
5782 ------------------------------
5783 -- Check_Delayed_Subprogram --
5784 ------------------------------
5786 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5787 procedure Possible_Freeze (T : Entity_Id);
5788 -- T is the type of either a formal parameter or of the return type. If
5789 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5790 -- itself must be delayed.
5792 ---------------------
5793 -- Possible_Freeze --
5794 ---------------------
5796 procedure Possible_Freeze (T : Entity_Id) is
5797 Scop : constant Entity_Id := Scope (Designator);
5800 -- If the subprogram appears within a package instance (which may be
5801 -- the wrapper package of a subprogram instance) the freeze node for
5802 -- that package will freeze the subprogram at the proper place, so
5803 -- do not emit a freeze node for the subprogram, given that it may
5804 -- appear in the wrong scope.
5806 if Ekind (Scop) = E_Package
5807 and then not Comes_From_Source (Scop)
5808 and then Is_Generic_Instance (Scop)
5812 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5813 Set_Has_Delayed_Freeze (Designator);
5815 elsif Is_Access_Type (T)
5816 and then Has_Delayed_Freeze (Designated_Type (T))
5817 and then not Is_Frozen (Designated_Type (T))
5819 Set_Has_Delayed_Freeze (Designator);
5821 end Possible_Freeze;
5827 -- Start of processing for Check_Delayed_Subprogram
5830 -- All subprograms, including abstract subprograms, may need a freeze
5831 -- node if some formal type or the return type needs one.
5833 Possible_Freeze (Etype (Designator));
5834 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5836 -- Need delayed freeze if any of the formal types themselves need a
5837 -- delayed freeze and are not yet frozen.
5839 F := First_Formal (Designator);
5840 while Present (F) loop
5841 Possible_Freeze (Etype (F));
5842 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5846 -- Mark functions that return by reference. Note that it cannot be done
5847 -- for delayed_freeze subprograms because the underlying returned type
5848 -- may not be known yet (for private types).
5850 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5852 Typ : constant Entity_Id := Etype (Designator);
5853 Utyp : constant Entity_Id := Underlying_Type (Typ);
5856 if Is_Limited_View (Typ) then
5857 Set_Returns_By_Ref (Designator);
5859 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5860 Set_Returns_By_Ref (Designator);
5864 end Check_Delayed_Subprogram;
5866 ------------------------------------
5867 -- Check_Discriminant_Conformance --
5868 ------------------------------------
5870 procedure Check_Discriminant_Conformance
5875 Old_Discr : Entity_Id := First_Discriminant (Prev);
5876 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5877 New_Discr_Id : Entity_Id;
5878 New_Discr_Type : Entity_Id;
5880 procedure Conformance_Error (Msg : String; N : Node_Id);
5881 -- Post error message for conformance error on given node. Two messages
5882 -- are output. The first points to the previous declaration with a
5883 -- general "no conformance" message. The second is the detailed reason,
5884 -- supplied as Msg. The parameter N provide information for a possible
5885 -- & insertion in the message.
5887 -----------------------
5888 -- Conformance_Error --
5889 -----------------------
5891 procedure Conformance_Error (Msg : String; N : Node_Id) is
5893 Error_Msg_Sloc := Sloc (Prev_Loc);
5894 Error_Msg_N -- CODEFIX
5895 ("not fully conformant with declaration#!", N);
5896 Error_Msg_NE (Msg, N, N);
5897 end Conformance_Error;
5899 -- Start of processing for Check_Discriminant_Conformance
5902 while Present (Old_Discr) and then Present (New_Discr) loop
5903 New_Discr_Id := Defining_Identifier (New_Discr);
5905 -- The subtype mark of the discriminant on the full type has not
5906 -- been analyzed so we do it here. For an access discriminant a new
5909 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5911 Access_Definition (N, Discriminant_Type (New_Discr));
5914 Analyze (Discriminant_Type (New_Discr));
5915 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5917 -- Ada 2005: if the discriminant definition carries a null
5918 -- exclusion, create an itype to check properly for consistency
5919 -- with partial declaration.
5921 if Is_Access_Type (New_Discr_Type)
5922 and then Null_Exclusion_Present (New_Discr)
5925 Create_Null_Excluding_Itype
5926 (T => New_Discr_Type,
5927 Related_Nod => New_Discr,
5928 Scope_Id => Current_Scope);
5932 if not Conforming_Types
5933 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5935 Conformance_Error ("type of & does not match!", New_Discr_Id);
5938 -- Treat the new discriminant as an occurrence of the old one,
5939 -- for navigation purposes, and fill in some semantic
5940 -- information, for completeness.
5942 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5943 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5944 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5949 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5950 Conformance_Error ("name & does not match!", New_Discr_Id);
5954 -- Default expressions must match
5957 NewD : constant Boolean :=
5958 Present (Expression (New_Discr));
5959 OldD : constant Boolean :=
5960 Present (Expression (Parent (Old_Discr)));
5963 if NewD or OldD then
5965 -- The old default value has been analyzed and expanded,
5966 -- because the current full declaration will have frozen
5967 -- everything before. The new default values have not been
5968 -- expanded, so expand now to check conformance.
5971 Preanalyze_Spec_Expression
5972 (Expression (New_Discr), New_Discr_Type);
5975 if not (NewD and OldD)
5976 or else not Fully_Conformant_Expressions
5977 (Expression (Parent (Old_Discr)),
5978 Expression (New_Discr))
5982 ("default expression for & does not match!",
5989 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
5991 if Ada_Version = Ada_83 then
5993 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
5996 -- Grouping (use of comma in param lists) must be the same
5997 -- This is where we catch a misconformance like:
6000 -- A : Integer; B : Integer
6002 -- which are represented identically in the tree except
6003 -- for the setting of the flags More_Ids and Prev_Ids.
6005 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6006 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6009 ("grouping of & does not match!", New_Discr_Id);
6015 Next_Discriminant (Old_Discr);
6019 if Present (Old_Discr) then
6020 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6023 elsif Present (New_Discr) then
6025 ("too many discriminants!", Defining_Identifier (New_Discr));
6028 end Check_Discriminant_Conformance;
6030 ----------------------------
6031 -- Check_Fully_Conformant --
6032 ----------------------------
6034 procedure Check_Fully_Conformant
6035 (New_Id : Entity_Id;
6037 Err_Loc : Node_Id := Empty)
6040 pragma Warnings (Off, Result);
6043 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6044 end Check_Fully_Conformant;
6046 --------------------------
6047 -- Check_Limited_Return --
6048 --------------------------
6050 procedure Check_Limited_Return
6056 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6057 -- replaced by anonymous access results. This is an incompatibility with
6058 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6059 -- controllable with special switch. ???
6061 -- A limited interface that is not immutably limited is OK
6063 if Is_Limited_Interface (R_Type)
6065 not (Is_Task_Interface (R_Type)
6066 or else Is_Protected_Interface (R_Type)
6067 or else Is_Synchronized_Interface (R_Type))
6071 elsif Is_Limited_Type (R_Type)
6072 and then not Is_Interface (R_Type)
6073 and then Comes_From_Source (N)
6074 and then not In_Instance_Body
6075 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6077 -- Error in Ada 2005
6079 if Ada_Version >= Ada_2005
6080 and then not Debug_Flag_Dot_L
6081 and then not GNAT_Mode
6084 ("(Ada 2005) cannot copy object of a limited type "
6085 & "(RM-2005 6.5(5.5/2))", Expr);
6087 if Is_Limited_View (R_Type) then
6089 ("\return by reference not permitted in Ada 2005", Expr);
6092 -- Warn in Ada 95 mode, to give folks a heads up about this
6095 -- In GNAT mode, this is just a warning, to allow it to be evilly
6096 -- turned off. Otherwise it is a real error.
6098 -- In a generic context, simplify the warning because it makes no
6099 -- sense to discuss pass-by-reference or copy.
6101 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6102 if Inside_A_Generic then
6104 ("return of limited object not permitted in Ada 2005 "
6105 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6107 elsif Is_Limited_View (R_Type) then
6109 ("return by reference not permitted in Ada 2005 "
6110 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6113 ("cannot copy object of a limited type in Ada 2005 "
6114 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6117 -- Ada 95 mode, and compatibility warnings disabled
6120 pragma Assert (Ada_Version <= Ada_95);
6121 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6122 return; -- skip continuation messages below
6125 if not Inside_A_Generic then
6127 ("\consider switching to return of access type", Expr);
6128 Explain_Limited_Type (R_Type, Expr);
6131 end Check_Limited_Return;
6133 ---------------------------
6134 -- Check_Mode_Conformant --
6135 ---------------------------
6137 procedure Check_Mode_Conformant
6138 (New_Id : Entity_Id;
6140 Err_Loc : Node_Id := Empty;
6141 Get_Inst : Boolean := False)
6144 pragma Warnings (Off, Result);
6147 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6148 end Check_Mode_Conformant;
6150 --------------------------------
6151 -- Check_Overriding_Indicator --
6152 --------------------------------
6154 procedure Check_Overriding_Indicator
6156 Overridden_Subp : Entity_Id;
6157 Is_Primitive : Boolean)
6163 -- No overriding indicator for literals
6165 if Ekind (Subp) = E_Enumeration_Literal then
6168 elsif Ekind (Subp) = E_Entry then
6169 Decl := Parent (Subp);
6171 -- No point in analyzing a malformed operator
6173 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6174 and then Error_Posted (Subp)
6179 Decl := Unit_Declaration_Node (Subp);
6182 if Nkind_In (Decl, N_Subprogram_Body,
6183 N_Subprogram_Body_Stub,
6184 N_Subprogram_Declaration,
6185 N_Abstract_Subprogram_Declaration,
6186 N_Subprogram_Renaming_Declaration)
6188 Spec := Specification (Decl);
6190 elsif Nkind (Decl) = N_Entry_Declaration then
6197 -- The overriding operation is type conformant with the overridden one,
6198 -- but the names of the formals are not required to match. If the names
6199 -- appear permuted in the overriding operation, this is a possible
6200 -- source of confusion that is worth diagnosing. Controlling formals
6201 -- often carry names that reflect the type, and it is not worthwhile
6202 -- requiring that their names match.
6204 if Present (Overridden_Subp)
6205 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6212 Form1 := First_Formal (Subp);
6213 Form2 := First_Formal (Overridden_Subp);
6215 -- If the overriding operation is a synchronized operation, skip
6216 -- the first parameter of the overridden operation, which is
6217 -- implicit in the new one. If the operation is declared in the
6218 -- body it is not primitive and all formals must match.
6220 if Is_Concurrent_Type (Scope (Subp))
6221 and then Is_Tagged_Type (Scope (Subp))
6222 and then not Has_Completion (Scope (Subp))
6224 Form2 := Next_Formal (Form2);
6227 if Present (Form1) then
6228 Form1 := Next_Formal (Form1);
6229 Form2 := Next_Formal (Form2);
6232 while Present (Form1) loop
6233 if not Is_Controlling_Formal (Form1)
6234 and then Present (Next_Formal (Form2))
6235 and then Chars (Form1) = Chars (Next_Formal (Form2))
6237 Error_Msg_Node_2 := Alias (Overridden_Subp);
6238 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6240 ("& does not match corresponding formal of&#",
6245 Next_Formal (Form1);
6246 Next_Formal (Form2);
6251 -- If there is an overridden subprogram, then check that there is no
6252 -- "not overriding" indicator, and mark the subprogram as overriding.
6253 -- This is not done if the overridden subprogram is marked as hidden,
6254 -- which can occur for the case of inherited controlled operations
6255 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6256 -- subprogram is not itself hidden. (Note: This condition could probably
6257 -- be simplified, leaving out the testing for the specific controlled
6258 -- cases, but it seems safer and clearer this way, and echoes similar
6259 -- special-case tests of this kind in other places.)
6261 if Present (Overridden_Subp)
6262 and then (not Is_Hidden (Overridden_Subp)
6264 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6267 and then Present (Alias (Overridden_Subp))
6268 and then not Is_Hidden (Alias (Overridden_Subp))))
6270 if Must_Not_Override (Spec) then
6271 Error_Msg_Sloc := Sloc (Overridden_Subp);
6273 if Ekind (Subp) = E_Entry then
6275 ("entry & overrides inherited operation #", Spec, Subp);
6278 ("subprogram & overrides inherited operation #", Spec, Subp);
6281 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6282 -- as an extension of Root_Controlled, and thus has a useless Adjust
6283 -- operation. This operation should not be inherited by other limited
6284 -- controlled types. An explicit Adjust for them is not overriding.
6286 elsif Must_Override (Spec)
6287 and then Chars (Overridden_Subp) = Name_Adjust
6288 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6289 and then Present (Alias (Overridden_Subp))
6290 and then In_Predefined_Unit (Alias (Overridden_Subp))
6293 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6294 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6296 elsif Is_Subprogram (Subp) then
6297 if Is_Init_Proc (Subp) then
6300 elsif No (Overridden_Operation (Subp)) then
6302 -- For entities generated by Derive_Subprograms the overridden
6303 -- operation is the inherited primitive (which is available
6304 -- through the attribute alias)
6306 if (Is_Dispatching_Operation (Subp)
6307 or else Is_Dispatching_Operation (Overridden_Subp))
6308 and then not Comes_From_Source (Overridden_Subp)
6309 and then Find_Dispatching_Type (Overridden_Subp) =
6310 Find_Dispatching_Type (Subp)
6311 and then Present (Alias (Overridden_Subp))
6312 and then Comes_From_Source (Alias (Overridden_Subp))
6314 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6315 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6318 Set_Overridden_Operation (Subp, Overridden_Subp);
6319 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6324 -- If primitive flag is set or this is a protected operation, then
6325 -- the operation is overriding at the point of its declaration, so
6326 -- warn if necessary. Otherwise it may have been declared before the
6327 -- operation it overrides and no check is required.
6330 and then not Must_Override (Spec)
6331 and then (Is_Primitive
6332 or else Ekind (Scope (Subp)) = E_Protected_Type)
6334 Style.Missing_Overriding (Decl, Subp);
6337 -- If Subp is an operator, it may override a predefined operation, if
6338 -- it is defined in the same scope as the type to which it applies.
6339 -- In that case Overridden_Subp is empty because of our implicit
6340 -- representation for predefined operators. We have to check whether the
6341 -- signature of Subp matches that of a predefined operator. Note that
6342 -- first argument provides the name of the operator, and the second
6343 -- argument the signature that may match that of a standard operation.
6344 -- If the indicator is overriding, then the operator must match a
6345 -- predefined signature, because we know already that there is no
6346 -- explicit overridden operation.
6348 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6349 if Must_Not_Override (Spec) then
6351 -- If this is not a primitive or a protected subprogram, then
6352 -- "not overriding" is illegal.
6355 and then Ekind (Scope (Subp)) /= E_Protected_Type
6357 Error_Msg_N ("overriding indicator only allowed "
6358 & "if subprogram is primitive", Subp);
6360 elsif Can_Override_Operator (Subp) then
6362 ("subprogram& overrides predefined operator ", Spec, Subp);
6365 elsif Must_Override (Spec) then
6366 if No (Overridden_Operation (Subp))
6367 and then not Can_Override_Operator (Subp)
6369 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6372 elsif not Error_Posted (Subp)
6373 and then Style_Check
6374 and then Can_Override_Operator (Subp)
6375 and then not In_Predefined_Unit (Subp)
6377 -- If style checks are enabled, indicate that the indicator is
6378 -- missing. However, at the point of declaration, the type of
6379 -- which this is a primitive operation may be private, in which
6380 -- case the indicator would be premature.
6382 if Has_Private_Declaration (Etype (Subp))
6383 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6387 Style.Missing_Overriding (Decl, Subp);
6391 elsif Must_Override (Spec) then
6392 if Ekind (Subp) = E_Entry then
6393 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6395 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6398 -- If the operation is marked "not overriding" and it's not primitive
6399 -- then an error is issued, unless this is an operation of a task or
6400 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6401 -- has been specified have already been checked above.
6403 elsif Must_Not_Override (Spec)
6404 and then not Is_Primitive
6405 and then Ekind (Subp) /= E_Entry
6406 and then Ekind (Scope (Subp)) /= E_Protected_Type
6409 ("overriding indicator only allowed if subprogram is primitive",
6413 end Check_Overriding_Indicator;
6419 -- Note: this procedure needs to know far too much about how the expander
6420 -- messes with exceptions. The use of the flag Exception_Junk and the
6421 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6422 -- works, but is not very clean. It would be better if the expansion
6423 -- routines would leave Original_Node working nicely, and we could use
6424 -- Original_Node here to ignore all the peculiar expander messing ???
6426 procedure Check_Returns
6430 Proc : Entity_Id := Empty)
6434 procedure Check_Statement_Sequence (L : List_Id);
6435 -- Internal recursive procedure to check a list of statements for proper
6436 -- termination by a return statement (or a transfer of control or a
6437 -- compound statement that is itself internally properly terminated).
6439 ------------------------------
6440 -- Check_Statement_Sequence --
6441 ------------------------------
6443 procedure Check_Statement_Sequence (L : List_Id) is
6448 function Assert_False return Boolean;
6449 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6450 -- rewritten as a null statement when assertions are off. The assert
6451 -- is not active, but it is still enough to kill the warning.
6457 function Assert_False return Boolean is
6458 Orig : constant Node_Id := Original_Node (Last_Stm);
6461 if Nkind (Orig) = N_Pragma
6462 and then Pragma_Name (Orig) = Name_Assert
6463 and then not Error_Posted (Orig)
6466 Arg : constant Node_Id :=
6467 First (Pragma_Argument_Associations (Orig));
6468 Exp : constant Node_Id := Expression (Arg);
6470 return Nkind (Exp) = N_Identifier
6471 and then Chars (Exp) = Name_False;
6481 Raise_Exception_Call : Boolean;
6482 -- Set True if statement sequence terminated by Raise_Exception call
6483 -- or a Reraise_Occurrence call.
6485 -- Start of processing for Check_Statement_Sequence
6488 Raise_Exception_Call := False;
6490 -- Get last real statement
6492 Last_Stm := Last (L);
6494 -- Deal with digging out exception handler statement sequences that
6495 -- have been transformed by the local raise to goto optimization.
6496 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6497 -- optimization has occurred, we are looking at something like:
6500 -- original stmts in block
6504 -- goto L1; | omitted if No_Exception_Propagation
6509 -- goto L3; -- skip handler when exception not raised
6511 -- <<L1>> -- target label for local exception
6525 -- and what we have to do is to dig out the estmts1 and estmts2
6526 -- sequences (which were the original sequences of statements in
6527 -- the exception handlers) and check them.
6529 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6534 exit when Nkind (Stm) /= N_Block_Statement;
6535 exit when not Exception_Junk (Stm);
6538 exit when Nkind (Stm) /= N_Label;
6539 exit when not Exception_Junk (Stm);
6540 Check_Statement_Sequence
6541 (Statements (Handled_Statement_Sequence (Next (Stm))));
6546 exit when Nkind (Stm) /= N_Goto_Statement;
6547 exit when not Exception_Junk (Stm);
6551 -- Don't count pragmas
6553 while Nkind (Last_Stm) = N_Pragma
6555 -- Don't count call to SS_Release (can happen after Raise_Exception)
6558 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6560 Nkind (Name (Last_Stm)) = N_Identifier
6562 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6564 -- Don't count exception junk
6567 (Nkind_In (Last_Stm, N_Goto_Statement,
6569 N_Object_Declaration)
6570 and then Exception_Junk (Last_Stm))
6571 or else Nkind (Last_Stm) in N_Push_xxx_Label
6572 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6574 -- Inserted code, such as finalization calls, is irrelevant: we only
6575 -- need to check original source.
6577 or else Is_Rewrite_Insertion (Last_Stm)
6582 -- Here we have the "real" last statement
6584 Kind := Nkind (Last_Stm);
6586 -- Transfer of control, OK. Note that in the No_Return procedure
6587 -- case, we already diagnosed any explicit return statements, so
6588 -- we can treat them as OK in this context.
6590 if Is_Transfer (Last_Stm) then
6593 -- Check cases of explicit non-indirect procedure calls
6595 elsif Kind = N_Procedure_Call_Statement
6596 and then Is_Entity_Name (Name (Last_Stm))
6598 -- Check call to Raise_Exception procedure which is treated
6599 -- specially, as is a call to Reraise_Occurrence.
6601 -- We suppress the warning in these cases since it is likely that
6602 -- the programmer really does not expect to deal with the case
6603 -- of Null_Occurrence, and thus would find a warning about a
6604 -- missing return curious, and raising Program_Error does not
6605 -- seem such a bad behavior if this does occur.
6607 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6608 -- behavior will be to raise Constraint_Error (see AI-329).
6610 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6612 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6614 Raise_Exception_Call := True;
6616 -- For Raise_Exception call, test first argument, if it is
6617 -- an attribute reference for a 'Identity call, then we know
6618 -- that the call cannot possibly return.
6621 Arg : constant Node_Id :=
6622 Original_Node (First_Actual (Last_Stm));
6624 if Nkind (Arg) = N_Attribute_Reference
6625 and then Attribute_Name (Arg) = Name_Identity
6632 -- If statement, need to look inside if there is an else and check
6633 -- each constituent statement sequence for proper termination.
6635 elsif Kind = N_If_Statement
6636 and then Present (Else_Statements (Last_Stm))
6638 Check_Statement_Sequence (Then_Statements (Last_Stm));
6639 Check_Statement_Sequence (Else_Statements (Last_Stm));
6641 if Present (Elsif_Parts (Last_Stm)) then
6643 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6646 while Present (Elsif_Part) loop
6647 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6655 -- Case statement, check each case for proper termination
6657 elsif Kind = N_Case_Statement then
6661 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6662 while Present (Case_Alt) loop
6663 Check_Statement_Sequence (Statements (Case_Alt));
6664 Next_Non_Pragma (Case_Alt);
6670 -- Block statement, check its handled sequence of statements
6672 elsif Kind = N_Block_Statement then
6678 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6687 -- Loop statement. If there is an iteration scheme, we can definitely
6688 -- fall out of the loop. Similarly if there is an exit statement, we
6689 -- can fall out. In either case we need a following return.
6691 elsif Kind = N_Loop_Statement then
6692 if Present (Iteration_Scheme (Last_Stm))
6693 or else Has_Exit (Entity (Identifier (Last_Stm)))
6697 -- A loop with no exit statement or iteration scheme is either
6698 -- an infinite loop, or it has some other exit (raise/return).
6699 -- In either case, no warning is required.
6705 -- Timed entry call, check entry call and delay alternatives
6707 -- Note: in expanded code, the timed entry call has been converted
6708 -- to a set of expanded statements on which the check will work
6709 -- correctly in any case.
6711 elsif Kind = N_Timed_Entry_Call then
6713 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6714 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6717 -- If statement sequence of entry call alternative is missing,
6718 -- then we can definitely fall through, and we post the error
6719 -- message on the entry call alternative itself.
6721 if No (Statements (ECA)) then
6724 -- If statement sequence of delay alternative is missing, then
6725 -- we can definitely fall through, and we post the error
6726 -- message on the delay alternative itself.
6728 -- Note: if both ECA and DCA are missing the return, then we
6729 -- post only one message, should be enough to fix the bugs.
6730 -- If not we will get a message next time on the DCA when the
6733 elsif No (Statements (DCA)) then
6736 -- Else check both statement sequences
6739 Check_Statement_Sequence (Statements (ECA));
6740 Check_Statement_Sequence (Statements (DCA));
6745 -- Conditional entry call, check entry call and else part
6747 -- Note: in expanded code, the conditional entry call has been
6748 -- converted to a set of expanded statements on which the check
6749 -- will work correctly in any case.
6751 elsif Kind = N_Conditional_Entry_Call then
6753 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6756 -- If statement sequence of entry call alternative is missing,
6757 -- then we can definitely fall through, and we post the error
6758 -- message on the entry call alternative itself.
6760 if No (Statements (ECA)) then
6763 -- Else check statement sequence and else part
6766 Check_Statement_Sequence (Statements (ECA));
6767 Check_Statement_Sequence (Else_Statements (Last_Stm));
6773 -- If we fall through, issue appropriate message
6777 -- Kill warning if last statement is a raise exception call,
6778 -- or a pragma Assert (False). Note that with assertions enabled,
6779 -- such a pragma has been converted into a raise exception call
6780 -- already, so the Assert_False is for the assertions off case.
6782 if not Raise_Exception_Call and then not Assert_False then
6784 -- In GNATprove mode, it is an error to have a missing return
6786 Error_Msg_Warn := SPARK_Mode /= On;
6788 -- Issue error message or warning
6791 ("RETURN statement missing following this statement<<!",
6794 ("\Program_Error ]<<!", Last_Stm);
6797 -- Note: we set Err even though we have not issued a warning
6798 -- because we still have a case of a missing return. This is
6799 -- an extremely marginal case, probably will never be noticed
6800 -- but we might as well get it right.
6804 -- Otherwise we have the case of a procedure marked No_Return
6807 if not Raise_Exception_Call then
6808 if GNATprove_Mode then
6810 ("implied return after this statement would have raised "
6811 & "Program_Error", Last_Stm);
6813 -- In normal compilation mode, do not warn on a generated call
6814 -- (e.g. in the body of a renaming as completion).
6816 elsif Comes_From_Source (Last_Stm) then
6818 ("implied return after this statement will raise "
6819 & "Program_Error??", Last_Stm);
6822 Error_Msg_Warn := SPARK_Mode /= On;
6824 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6828 RE : constant Node_Id :=
6829 Make_Raise_Program_Error (Sloc (Last_Stm),
6830 Reason => PE_Implicit_Return);
6832 Insert_After (Last_Stm, RE);
6836 end Check_Statement_Sequence;
6838 -- Start of processing for Check_Returns
6842 Check_Statement_Sequence (Statements (HSS));
6844 if Present (Exception_Handlers (HSS)) then
6845 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6846 while Present (Handler) loop
6847 Check_Statement_Sequence (Statements (Handler));
6848 Next_Non_Pragma (Handler);
6853 ----------------------------
6854 -- Check_Subprogram_Order --
6855 ----------------------------
6857 procedure Check_Subprogram_Order (N : Node_Id) is
6859 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6860 -- This is used to check if S1 > S2 in the sense required by this test,
6861 -- for example nameab < namec, but name2 < name10.
6863 -----------------------------
6864 -- Subprogram_Name_Greater --
6865 -----------------------------
6867 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6872 -- Deal with special case where names are identical except for a
6873 -- numerical suffix. These are handled specially, taking the numeric
6874 -- ordering from the suffix into account.
6877 while S1 (L1) in '0' .. '9' loop
6882 while S2 (L2) in '0' .. '9' loop
6886 -- If non-numeric parts non-equal, do straight compare
6888 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6891 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6892 -- that a missing suffix is treated as numeric zero in this test.
6896 while L1 < S1'Last loop
6898 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6902 while L2 < S2'Last loop
6904 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6909 end Subprogram_Name_Greater;
6911 -- Start of processing for Check_Subprogram_Order
6914 -- Check body in alpha order if this is option
6917 and then Style_Check_Order_Subprograms
6918 and then Nkind (N) = N_Subprogram_Body
6919 and then Comes_From_Source (N)
6920 and then In_Extended_Main_Source_Unit (N)
6924 renames Scope_Stack.Table
6925 (Scope_Stack.Last).Last_Subprogram_Name;
6927 Body_Id : constant Entity_Id :=
6928 Defining_Entity (Specification (N));
6931 Get_Decoded_Name_String (Chars (Body_Id));
6934 if Subprogram_Name_Greater
6935 (LSN.all, Name_Buffer (1 .. Name_Len))
6937 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6943 LSN := new String'(Name_Buffer (1 .. Name_Len));
6946 end Check_Subprogram_Order;
6948 ------------------------------
6949 -- Check_Subtype_Conformant --
6950 ------------------------------
6952 procedure Check_Subtype_Conformant
6953 (New_Id : Entity_Id;
6955 Err_Loc : Node_Id := Empty;
6956 Skip_Controlling_Formals : Boolean := False;
6957 Get_Inst : Boolean := False)
6960 pragma Warnings (Off, Result);
6963 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6964 Skip_Controlling_Formals => Skip_Controlling_Formals,
6965 Get_Inst => Get_Inst);
6966 end Check_Subtype_Conformant;
6968 -----------------------------------
6969 -- Check_Synchronized_Overriding --
6970 -----------------------------------
6972 procedure Check_Synchronized_Overriding
6973 (Def_Id : Entity_Id;
6974 Overridden_Subp : out Entity_Id)
6976 Ifaces_List : Elist_Id;
6980 function Matches_Prefixed_View_Profile
6981 (Prim_Params : List_Id;
6982 Iface_Params : List_Id) return Boolean;
6983 -- Determine whether a subprogram's parameter profile Prim_Params
6984 -- matches that of a potentially overridden interface subprogram
6985 -- Iface_Params. Also determine if the type of first parameter of
6986 -- Iface_Params is an implemented interface.
6988 -----------------------------------
6989 -- Matches_Prefixed_View_Profile --
6990 -----------------------------------
6992 function Matches_Prefixed_View_Profile
6993 (Prim_Params : List_Id;
6994 Iface_Params : List_Id) return Boolean
6996 function Is_Implemented
6997 (Ifaces_List : Elist_Id;
6998 Iface : Entity_Id) return Boolean;
6999 -- Determine if Iface is implemented by the current task or
7002 --------------------
7003 -- Is_Implemented --
7004 --------------------
7006 function Is_Implemented
7007 (Ifaces_List : Elist_Id;
7008 Iface : Entity_Id) return Boolean
7010 Iface_Elmt : Elmt_Id;
7013 Iface_Elmt := First_Elmt (Ifaces_List);
7014 while Present (Iface_Elmt) loop
7015 if Node (Iface_Elmt) = Iface then
7019 Next_Elmt (Iface_Elmt);
7027 Iface_Id : Entity_Id;
7028 Iface_Param : Node_Id;
7029 Iface_Typ : Entity_Id;
7030 Prim_Id : Entity_Id;
7031 Prim_Param : Node_Id;
7032 Prim_Typ : Entity_Id;
7034 -- Start of processing for Matches_Prefixed_View_Profile
7037 Iface_Param := First (Iface_Params);
7038 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7040 if Is_Access_Type (Iface_Typ) then
7041 Iface_Typ := Designated_Type (Iface_Typ);
7044 Prim_Param := First (Prim_Params);
7046 -- The first parameter of the potentially overridden subprogram must
7047 -- be an interface implemented by Prim.
7049 if not Is_Interface (Iface_Typ)
7050 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7055 -- The checks on the object parameters are done, so move on to the
7056 -- rest of the parameters.
7058 if not In_Scope then
7059 Prim_Param := Next (Prim_Param);
7062 Iface_Param := Next (Iface_Param);
7063 while Present (Iface_Param) and then Present (Prim_Param) loop
7064 Iface_Id := Defining_Identifier (Iface_Param);
7065 Iface_Typ := Find_Parameter_Type (Iface_Param);
7067 Prim_Id := Defining_Identifier (Prim_Param);
7068 Prim_Typ := Find_Parameter_Type (Prim_Param);
7070 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7071 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7072 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7074 Iface_Typ := Designated_Type (Iface_Typ);
7075 Prim_Typ := Designated_Type (Prim_Typ);
7078 -- Case of multiple interface types inside a parameter profile
7080 -- (Obj_Param : in out Iface; ...; Param : Iface)
7082 -- If the interface type is implemented, then the matching type in
7083 -- the primitive should be the implementing record type.
7085 if Ekind (Iface_Typ) = E_Record_Type
7086 and then Is_Interface (Iface_Typ)
7087 and then Is_Implemented (Ifaces_List, Iface_Typ)
7089 if Prim_Typ /= Typ then
7093 -- The two parameters must be both mode and subtype conformant
7095 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7097 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7106 -- One of the two lists contains more parameters than the other
7108 if Present (Iface_Param) or else Present (Prim_Param) then
7113 end Matches_Prefixed_View_Profile;
7115 -- Start of processing for Check_Synchronized_Overriding
7118 Overridden_Subp := Empty;
7120 -- Def_Id must be an entry or a subprogram. We should skip predefined
7121 -- primitives internally generated by the front end; however at this
7122 -- stage predefined primitives are still not fully decorated. As a
7123 -- minor optimization we skip here internally generated subprograms.
7125 if (Ekind (Def_Id) /= E_Entry
7126 and then Ekind (Def_Id) /= E_Function
7127 and then Ekind (Def_Id) /= E_Procedure)
7128 or else not Comes_From_Source (Def_Id)
7133 -- Search for the concurrent declaration since it contains the list of
7134 -- all implemented interfaces. In this case, the subprogram is declared
7135 -- within the scope of a protected or a task type.
7137 if Present (Scope (Def_Id))
7138 and then Is_Concurrent_Type (Scope (Def_Id))
7139 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7141 Typ := Scope (Def_Id);
7144 -- The enclosing scope is not a synchronized type and the subprogram
7147 elsif No (First_Formal (Def_Id)) then
7150 -- The subprogram has formals and hence it may be a primitive of a
7154 Typ := Etype (First_Formal (Def_Id));
7156 if Is_Access_Type (Typ) then
7157 Typ := Directly_Designated_Type (Typ);
7160 if Is_Concurrent_Type (Typ)
7161 and then not Is_Generic_Actual_Type (Typ)
7165 -- This case occurs when the concurrent type is declared within a
7166 -- generic unit. As a result the corresponding record has been built
7167 -- and used as the type of the first formal, we just have to retrieve
7168 -- the corresponding concurrent type.
7170 elsif Is_Concurrent_Record_Type (Typ)
7171 and then not Is_Class_Wide_Type (Typ)
7172 and then Present (Corresponding_Concurrent_Type (Typ))
7174 Typ := Corresponding_Concurrent_Type (Typ);
7182 -- There is no overriding to check if this is an inherited operation in
7183 -- a type derivation for a generic actual.
7185 Collect_Interfaces (Typ, Ifaces_List);
7187 if Is_Empty_Elmt_List (Ifaces_List) then
7191 -- Determine whether entry or subprogram Def_Id overrides a primitive
7192 -- operation that belongs to one of the interfaces in Ifaces_List.
7195 Candidate : Entity_Id := Empty;
7196 Hom : Entity_Id := Empty;
7197 Subp : Entity_Id := Empty;
7200 -- Traverse the homonym chain, looking for a potentially overridden
7201 -- subprogram that belongs to an implemented interface.
7203 Hom := Current_Entity_In_Scope (Def_Id);
7204 while Present (Hom) loop
7208 or else not Is_Overloadable (Subp)
7209 or else not Is_Primitive (Subp)
7210 or else not Is_Dispatching_Operation (Subp)
7211 or else not Present (Find_Dispatching_Type (Subp))
7212 or else not Is_Interface (Find_Dispatching_Type (Subp))
7216 -- Entries and procedures can override abstract or null interface
7219 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7220 and then Ekind (Subp) = E_Procedure
7221 and then Matches_Prefixed_View_Profile
7222 (Parameter_Specifications (Parent (Def_Id)),
7223 Parameter_Specifications (Parent (Subp)))
7227 -- For an overridden subprogram Subp, check whether the mode
7228 -- of its first parameter is correct depending on the kind of
7229 -- synchronized type.
7232 Formal : constant Node_Id := First_Formal (Candidate);
7235 -- In order for an entry or a protected procedure to
7236 -- override, the first parameter of the overridden routine
7237 -- must be of mode "out", "in out", or access-to-variable.
7239 if Ekind_In (Candidate, E_Entry, E_Procedure)
7240 and then Is_Protected_Type (Typ)
7241 and then Ekind (Formal) /= E_In_Out_Parameter
7242 and then Ekind (Formal) /= E_Out_Parameter
7243 and then Nkind (Parameter_Type (Parent (Formal))) /=
7248 -- All other cases are OK since a task entry or routine does
7249 -- not have a restriction on the mode of the first parameter
7250 -- of the overridden interface routine.
7253 Overridden_Subp := Candidate;
7258 -- Functions can override abstract interface functions. Return
7259 -- types must be subtype conformant.
7261 elsif Ekind (Def_Id) = E_Function
7262 and then Ekind (Subp) = E_Function
7263 and then Matches_Prefixed_View_Profile
7264 (Parameter_Specifications (Parent (Def_Id)),
7265 Parameter_Specifications (Parent (Subp)))
7266 and then Conforming_Types
7267 (Etype (Def_Id), Etype (Subp), Subtype_Conformant)
7271 -- If an inherited subprogram is implemented by a protected
7272 -- function, then the first parameter of the inherited
7273 -- subprogram shall be of mode in, but not an access-to-
7274 -- variable parameter (RM 9.4(11/9)).
7276 if Present (First_Formal (Subp))
7277 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7279 (not Is_Access_Type (Etype (First_Formal (Subp)))
7281 Is_Access_Constant (Etype (First_Formal (Subp))))
7283 Overridden_Subp := Subp;
7288 Hom := Homonym (Hom);
7291 -- After examining all candidates for overriding, we are left with
7292 -- the best match, which is a mode-incompatible interface routine.
7294 if In_Scope and then Present (Candidate) then
7295 Error_Msg_PT (Def_Id, Candidate);
7298 Overridden_Subp := Candidate;
7301 end Check_Synchronized_Overriding;
7303 ---------------------------
7304 -- Check_Type_Conformant --
7305 ---------------------------
7307 procedure Check_Type_Conformant
7308 (New_Id : Entity_Id;
7310 Err_Loc : Node_Id := Empty)
7313 pragma Warnings (Off, Result);
7316 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7317 end Check_Type_Conformant;
7319 ---------------------------
7320 -- Can_Override_Operator --
7321 ---------------------------
7323 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7327 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7331 Typ := Base_Type (Etype (First_Formal (Subp)));
7333 -- Check explicitly that the operation is a primitive of the type
7335 return Operator_Matches_Spec (Subp, Subp)
7336 and then not Is_Generic_Type (Typ)
7337 and then Scope (Subp) = Scope (Typ)
7338 and then not Is_Class_Wide_Type (Typ);
7340 end Can_Override_Operator;
7342 ----------------------
7343 -- Conforming_Types --
7344 ----------------------
7346 function Conforming_Types
7349 Ctype : Conformance_Type;
7350 Get_Inst : Boolean := False) return Boolean
7352 function Base_Types_Match
7354 Typ_2 : Entity_Id) return Boolean;
7355 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7356 -- in different scopes (e.g. parent and child instances), then verify
7357 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7358 -- the same subtype chain. The whole purpose of this procedure is to
7359 -- prevent spurious ambiguities in an instantiation that may arise if
7360 -- two distinct generic types are instantiated with the same actual.
7362 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7363 -- An access parameter can designate an incomplete type. If the
7364 -- incomplete type is the limited view of a type from a limited_
7365 -- with_clause, check whether the non-limited view is available.
7366 -- If it is a (non-limited) incomplete type, get the full view.
7368 function Matches_Limited_With_View
7370 Typ_2 : Entity_Id) return Boolean;
7371 -- Returns True if and only if either Typ_1 denotes a limited view of
7372 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7373 -- the limited with view of a type is used in a subprogram declaration
7374 -- and the subprogram body is in the scope of a regular with clause for
7375 -- the same unit. In such a case, the two type entities are considered
7376 -- identical for purposes of conformance checking.
7378 ----------------------
7379 -- Base_Types_Match --
7380 ----------------------
7382 function Base_Types_Match
7384 Typ_2 : Entity_Id) return Boolean
7386 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7387 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7390 if Typ_1 = Typ_2 then
7393 elsif Base_1 = Base_2 then
7395 -- The following is too permissive. A more precise test should
7396 -- check that the generic actual is an ancestor subtype of the
7399 -- See code in Find_Corresponding_Spec that applies an additional
7400 -- filter to handle accidental amiguities in instances.
7403 not Is_Generic_Actual_Type (Typ_1)
7404 or else not Is_Generic_Actual_Type (Typ_2)
7405 or else Scope (Typ_1) /= Scope (Typ_2);
7407 -- If Typ_2 is a generic actual type it is declared as the subtype of
7408 -- the actual. If that actual is itself a subtype we need to use its
7409 -- own base type to check for compatibility.
7411 elsif Ekind (Base_2) = Ekind (Typ_2)
7412 and then Base_1 = Base_Type (Base_2)
7416 elsif Ekind (Base_1) = Ekind (Typ_1)
7417 and then Base_2 = Base_Type (Base_1)
7424 end Base_Types_Match;
7426 --------------------------
7427 -- Find_Designated_Type --
7428 --------------------------
7430 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7434 Desig := Directly_Designated_Type (Typ);
7436 if Ekind (Desig) = E_Incomplete_Type then
7438 -- If regular incomplete type, get full view if available
7440 if Present (Full_View (Desig)) then
7441 Desig := Full_View (Desig);
7443 -- If limited view of a type, get non-limited view if available,
7444 -- and check again for a regular incomplete type.
7446 elsif Present (Non_Limited_View (Desig)) then
7447 Desig := Get_Full_View (Non_Limited_View (Desig));
7452 end Find_Designated_Type;
7454 -------------------------------
7455 -- Matches_Limited_With_View --
7456 -------------------------------
7458 function Matches_Limited_With_View
7460 Typ_2 : Entity_Id) return Boolean
7462 function Is_Matching_Limited_View
7464 View : Entity_Id) return Boolean;
7465 -- Determine whether non-limited view View denotes type Typ in some
7466 -- conformant fashion.
7468 ------------------------------
7469 -- Is_Matching_Limited_View --
7470 ------------------------------
7472 function Is_Matching_Limited_View
7474 View : Entity_Id) return Boolean
7476 Root_Typ : Entity_Id;
7477 Root_View : Entity_Id;
7480 -- The non-limited view directly denotes the type
7485 -- The type is a subtype of the non-limited view
7487 elsif Is_Subtype_Of (Typ, View) then
7490 -- Both the non-limited view and the type denote class-wide types
7492 elsif Is_Class_Wide_Type (Typ)
7493 and then Is_Class_Wide_Type (View)
7495 Root_Typ := Root_Type (Typ);
7496 Root_View := Root_Type (View);
7498 if Root_Typ = Root_View then
7501 -- An incomplete tagged type and its full view may receive two
7502 -- distinct class-wide types when the related package has not
7503 -- been analyzed yet.
7506 -- type T is tagged; -- CW_1
7507 -- type T is tagged null record; -- CW_2
7510 -- This is because the package lacks any semantic information
7511 -- that may eventually link both views of T. As a consequence,
7512 -- a client of the limited view of Pack will see CW_2 while a
7513 -- client of the non-limited view of Pack will see CW_1.
7515 elsif Is_Incomplete_Type (Root_Typ)
7516 and then Present (Full_View (Root_Typ))
7517 and then Full_View (Root_Typ) = Root_View
7521 elsif Is_Incomplete_Type (Root_View)
7522 and then Present (Full_View (Root_View))
7523 and then Full_View (Root_View) = Root_Typ
7530 end Is_Matching_Limited_View;
7532 -- Start of processing for Matches_Limited_With_View
7535 -- In some cases a type imported through a limited_with clause, and
7536 -- its non-limited view are both visible, for example in an anonymous
7537 -- access-to-class-wide type in a formal, or when building the body
7538 -- for a subprogram renaming after the subprogram has been frozen.
7539 -- In these cases both entities designate the same type. In addition,
7540 -- if one of them is an actual in an instance, it may be a subtype of
7541 -- the non-limited view of the other.
7543 if From_Limited_With (Typ_1)
7544 and then From_Limited_With (Typ_2)
7545 and then Available_View (Typ_1) = Available_View (Typ_2)
7549 elsif From_Limited_With (Typ_1) then
7550 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7552 elsif From_Limited_With (Typ_2) then
7553 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7558 end Matches_Limited_With_View;
7562 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7564 Type_1 : Entity_Id := T1;
7565 Type_2 : Entity_Id := T2;
7567 -- Start of processing for Conforming_Types
7570 -- The context is an instance association for a formal access-to-
7571 -- subprogram type; the formal parameter types require mapping because
7572 -- they may denote other formal parameters of the generic unit.
7575 Type_1 := Get_Instance_Of (T1);
7576 Type_2 := Get_Instance_Of (T2);
7579 -- If one of the types is a view of the other introduced by a limited
7580 -- with clause, treat these as conforming for all purposes.
7582 if Matches_Limited_With_View (T1, T2) then
7585 elsif Base_Types_Match (Type_1, Type_2) then
7586 if Ctype <= Mode_Conformant then
7591 Subtypes_Statically_Match (Type_1, Type_2)
7592 and then Dimensions_Match (Type_1, Type_2);
7595 elsif Is_Incomplete_Or_Private_Type (Type_1)
7596 and then Present (Full_View (Type_1))
7597 and then Base_Types_Match (Full_View (Type_1), Type_2)
7600 Ctype <= Mode_Conformant
7601 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7603 elsif Ekind (Type_2) = E_Incomplete_Type
7604 and then Present (Full_View (Type_2))
7605 and then Base_Types_Match (Type_1, Full_View (Type_2))
7608 Ctype <= Mode_Conformant
7609 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7611 elsif Is_Private_Type (Type_2)
7612 and then In_Instance
7613 and then Present (Full_View (Type_2))
7614 and then Base_Types_Match (Type_1, Full_View (Type_2))
7617 Ctype <= Mode_Conformant
7618 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7620 -- Another confusion between views in a nested instance with an
7621 -- actual private type whose full view is not in scope.
7623 elsif Ekind (Type_2) = E_Private_Subtype
7624 and then In_Instance
7625 and then Etype (Type_2) = Type_1
7629 -- In Ada 2012, incomplete types (including limited views) can appear
7630 -- as actuals in instantiations, where they are conformant to the
7631 -- corresponding incomplete formal.
7633 elsif Is_Incomplete_Type (Type_1)
7634 and then Is_Incomplete_Type (Type_2)
7635 and then In_Instance
7636 and then (Used_As_Generic_Actual (Type_1)
7637 or else Used_As_Generic_Actual (Type_2))
7642 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7643 -- treated recursively because they carry a signature. As far as
7644 -- conformance is concerned, convention plays no role, and either
7645 -- or both could be access to protected subprograms.
7647 Are_Anonymous_Access_To_Subprogram_Types :=
7648 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7649 E_Anonymous_Access_Protected_Subprogram_Type)
7651 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7652 E_Anonymous_Access_Protected_Subprogram_Type);
7654 -- Test anonymous access type case. For this case, static subtype
7655 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7656 -- the base types because we may have built internal subtype entities
7657 -- to handle null-excluding types (see Process_Formals).
7659 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7661 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7663 -- Ada 2005 (AI-254)
7665 or else Are_Anonymous_Access_To_Subprogram_Types
7668 Desig_1 : Entity_Id;
7669 Desig_2 : Entity_Id;
7672 -- In Ada 2005, access constant indicators must match for
7673 -- subtype conformance.
7675 if Ada_Version >= Ada_2005
7676 and then Ctype >= Subtype_Conformant
7678 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7683 Desig_1 := Find_Designated_Type (Type_1);
7684 Desig_2 := Find_Designated_Type (Type_2);
7686 -- If the context is an instance association for a formal
7687 -- access-to-subprogram type; formal access parameter designated
7688 -- types require mapping because they may denote other formal
7689 -- parameters of the generic unit.
7692 Desig_1 := Get_Instance_Of (Desig_1);
7693 Desig_2 := Get_Instance_Of (Desig_2);
7696 -- It is possible for a Class_Wide_Type to be introduced for an
7697 -- incomplete type, in which case there is a separate class_ wide
7698 -- type for the full view. The types conform if their Etypes
7699 -- conform, i.e. one may be the full view of the other. This can
7700 -- only happen in the context of an access parameter, other uses
7701 -- of an incomplete Class_Wide_Type are illegal.
7703 if Is_Class_Wide_Type (Desig_1)
7705 Is_Class_Wide_Type (Desig_2)
7709 (Etype (Base_Type (Desig_1)),
7710 Etype (Base_Type (Desig_2)), Ctype);
7712 elsif Are_Anonymous_Access_To_Subprogram_Types then
7713 if Ada_Version < Ada_2005 then
7715 Ctype = Type_Conformant
7716 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7718 -- We must check the conformance of the signatures themselves
7722 Conformant : Boolean;
7725 (Desig_1, Desig_2, Ctype, False, Conformant);
7730 -- A limited view of an actual matches the corresponding
7731 -- incomplete formal.
7733 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7734 and then From_Limited_With (Desig_2)
7735 and then Used_As_Generic_Actual (Etype (Desig_2))
7740 return Base_Type (Desig_1) = Base_Type (Desig_2)
7741 and then (Ctype = Type_Conformant
7743 Subtypes_Statically_Match (Desig_1, Desig_2));
7747 -- Otherwise definitely no match
7750 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7751 and then Is_Access_Type (Type_2))
7752 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7753 and then Is_Access_Type (Type_1)))
7756 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7758 May_Hide_Profile := True;
7763 end Conforming_Types;
7765 --------------------------
7766 -- Create_Extra_Formals --
7767 --------------------------
7769 procedure Create_Extra_Formals (E : Entity_Id) is
7770 First_Extra : Entity_Id := Empty;
7772 Last_Extra : Entity_Id := Empty;
7774 function Add_Extra_Formal
7775 (Assoc_Entity : Entity_Id;
7778 Suffix : String) return Entity_Id;
7779 -- Add an extra formal to the current list of formals and extra formals.
7780 -- The extra formal is added to the end of the list of extra formals,
7781 -- and also returned as the result. These formals are always of mode IN.
7782 -- The new formal has the type Typ, is declared in Scope, and its name
7783 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7784 -- The following suffixes are currently used. They should not be changed
7785 -- without coordinating with CodePeer, which makes use of these to
7786 -- provide better messages.
7788 -- O denotes the Constrained bit.
7789 -- L denotes the accessibility level.
7790 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7791 -- the full list in exp_ch6.BIP_Formal_Kind.
7793 ----------------------
7794 -- Add_Extra_Formal --
7795 ----------------------
7797 function Add_Extra_Formal
7798 (Assoc_Entity : Entity_Id;
7801 Suffix : String) return Entity_Id
7803 EF : constant Entity_Id :=
7804 Make_Defining_Identifier (Sloc (Assoc_Entity),
7805 Chars => New_External_Name (Chars (Assoc_Entity),
7809 -- A little optimization. Never generate an extra formal for the
7810 -- _init operand of an initialization procedure, since it could
7813 if Chars (Formal) = Name_uInit then
7817 Set_Ekind (EF, E_In_Parameter);
7818 Set_Actual_Subtype (EF, Typ);
7819 Set_Etype (EF, Typ);
7820 Set_Scope (EF, Scope);
7821 Set_Mechanism (EF, Default_Mechanism);
7822 Set_Formal_Validity (EF);
7824 if No (First_Extra) then
7826 Set_Extra_Formals (Scope, EF);
7829 if Present (Last_Extra) then
7830 Set_Extra_Formal (Last_Extra, EF);
7836 end Add_Extra_Formal;
7840 Formal_Type : Entity_Id;
7841 P_Formal : Entity_Id := Empty;
7843 -- Start of processing for Create_Extra_Formals
7846 -- We never generate extra formals if expansion is not active because we
7847 -- don't need them unless we are generating code.
7849 if not Expander_Active then
7853 -- No need to generate extra formals in interface thunks whose target
7854 -- primitive has no extra formals.
7856 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7860 -- If this is a derived subprogram then the subtypes of the parent
7861 -- subprogram's formal parameters will be used to determine the need
7862 -- for extra formals.
7864 if Is_Overloadable (E) and then Present (Alias (E)) then
7865 P_Formal := First_Formal (Alias (E));
7868 Formal := First_Formal (E);
7869 while Present (Formal) loop
7870 Last_Extra := Formal;
7871 Next_Formal (Formal);
7874 -- If Extra_Formals were already created, don't do it again. This
7875 -- situation may arise for subprogram types created as part of
7876 -- dispatching calls (see Expand_Dispatching_Call).
7878 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7882 -- If the subprogram is a predefined dispatching subprogram then don't
7883 -- generate any extra constrained or accessibility level formals. In
7884 -- general we suppress these for internal subprograms (by not calling
7885 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7886 -- generated stream attributes do get passed through because extra
7887 -- build-in-place formals are needed in some cases (limited 'Input).
7889 if Is_Predefined_Internal_Operation (E) then
7890 goto Test_For_Func_Result_Extras;
7893 Formal := First_Formal (E);
7894 while Present (Formal) loop
7896 -- Create extra formal for supporting the attribute 'Constrained.
7897 -- The case of a private type view without discriminants also
7898 -- requires the extra formal if the underlying type has defaulted
7901 if Ekind (Formal) /= E_In_Parameter then
7902 if Present (P_Formal) then
7903 Formal_Type := Etype (P_Formal);
7905 Formal_Type := Etype (Formal);
7908 -- Do not produce extra formals for Unchecked_Union parameters.
7909 -- Jump directly to the end of the loop.
7911 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7912 goto Skip_Extra_Formal_Generation;
7915 if not Has_Discriminants (Formal_Type)
7916 and then Ekind (Formal_Type) in Private_Kind
7917 and then Present (Underlying_Type (Formal_Type))
7919 Formal_Type := Underlying_Type (Formal_Type);
7922 -- Suppress the extra formal if formal's subtype is constrained or
7923 -- indefinite, or we're compiling for Ada 2012 and the underlying
7924 -- type is tagged and limited. In Ada 2012, a limited tagged type
7925 -- can have defaulted discriminants, but 'Constrained is required
7926 -- to return True, so the formal is never needed (see AI05-0214).
7927 -- Note that this ensures consistency of calling sequences for
7928 -- dispatching operations when some types in a class have defaults
7929 -- on discriminants and others do not (and requiring the extra
7930 -- formal would introduce distributed overhead).
7932 -- If the type does not have a completion yet, treat as prior to
7933 -- Ada 2012 for consistency.
7935 if Has_Discriminants (Formal_Type)
7936 and then not Is_Constrained (Formal_Type)
7937 and then Is_Definite_Subtype (Formal_Type)
7938 and then (Ada_Version < Ada_2012
7939 or else No (Underlying_Type (Formal_Type))
7941 (Is_Limited_Type (Formal_Type)
7944 (Underlying_Type (Formal_Type)))))
7946 Set_Extra_Constrained
7947 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7951 -- Create extra formal for supporting accessibility checking. This
7952 -- is done for both anonymous access formals and formals of named
7953 -- access types that are marked as controlling formals. The latter
7954 -- case can occur when Expand_Dispatching_Call creates a subprogram
7955 -- type and substitutes the types of access-to-class-wide actuals
7956 -- for the anonymous access-to-specific-type of controlling formals.
7957 -- Base_Type is applied because in cases where there is a null
7958 -- exclusion the formal may have an access subtype.
7960 -- This is suppressed if we specifically suppress accessibility
7961 -- checks at the package level for either the subprogram, or the
7962 -- package in which it resides. However, we do not suppress it
7963 -- simply if the scope has accessibility checks suppressed, since
7964 -- this could cause trouble when clients are compiled with a
7965 -- different suppression setting. The explicit checks at the
7966 -- package level are safe from this point of view.
7968 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7969 or else (Is_Controlling_Formal (Formal)
7970 and then Is_Access_Type (Base_Type (Etype (Formal)))))
7972 (Explicit_Suppress (E, Accessibility_Check)
7974 Explicit_Suppress (Scope (E), Accessibility_Check))
7977 or else Present (Extra_Accessibility (P_Formal)))
7979 Set_Extra_Accessibility
7980 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
7983 -- This label is required when skipping extra formal generation for
7984 -- Unchecked_Union parameters.
7986 <<Skip_Extra_Formal_Generation>>
7988 if Present (P_Formal) then
7989 Next_Formal (P_Formal);
7992 Next_Formal (Formal);
7995 <<Test_For_Func_Result_Extras>>
7997 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
7998 -- function call is ... determined by the point of call ...".
8000 if Needs_Result_Accessibility_Level (E) then
8001 Set_Extra_Accessibility_Of_Result
8002 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8005 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8006 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8008 if Is_Build_In_Place_Function (E) then
8010 Result_Subt : constant Entity_Id := Etype (E);
8011 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8012 Formal_Typ : Entity_Id;
8013 Subp_Decl : Node_Id;
8014 Discard : Entity_Id;
8017 -- In the case of functions with unconstrained result subtypes,
8018 -- add a 4-state formal indicating whether the return object is
8019 -- allocated by the caller (1), or should be allocated by the
8020 -- callee on the secondary stack (2), in the global heap (3), or
8021 -- in a user-defined storage pool (4). For the moment we just use
8022 -- Natural for the type of this formal. Note that this formal
8023 -- isn't usually needed in the case where the result subtype is
8024 -- constrained, but it is needed when the function has a tagged
8025 -- result, because generally such functions can be called in a
8026 -- dispatching context and such calls must be handled like calls
8027 -- to a class-wide function.
8029 if Needs_BIP_Alloc_Form (E) then
8032 (E, Standard_Natural,
8033 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8035 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8036 -- use a user-defined pool. This formal is not added on
8037 -- ZFP as those targets do not support pools.
8039 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8042 (E, RTE (RE_Root_Storage_Pool_Ptr),
8043 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8047 -- In the case of functions whose result type needs finalization,
8048 -- add an extra formal which represents the finalization master.
8050 if Needs_BIP_Finalization_Master (E) then
8053 (E, RTE (RE_Finalization_Master_Ptr),
8054 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8057 -- When the result type contains tasks, add two extra formals: the
8058 -- master of the tasks to be created, and the caller's activation
8061 if Has_Task (Full_Subt) then
8064 (E, RTE (RE_Master_Id),
8065 E, BIP_Formal_Suffix (BIP_Task_Master));
8068 (E, RTE (RE_Activation_Chain_Access),
8069 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8072 -- All build-in-place functions get an extra formal that will be
8073 -- passed the address of the return object within the caller.
8076 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8078 -- Incomplete_View_From_Limited_With is needed here because
8079 -- gigi gets confused if the designated type is the full view
8080 -- coming from a limited-with'ed package. In the normal case,
8081 -- (no limited with) Incomplete_View_From_Limited_With
8082 -- returns Result_Subt.
8084 Set_Directly_Designated_Type
8085 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8086 Set_Etype (Formal_Typ, Formal_Typ);
8087 Set_Depends_On_Private
8088 (Formal_Typ, Has_Private_Component (Formal_Typ));
8089 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8090 Set_Is_Access_Constant (Formal_Typ, False);
8092 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8093 -- the designated type comes from the limited view (for back-end
8096 Set_From_Limited_With
8097 (Formal_Typ, From_Limited_With (Result_Subt));
8099 Layout_Type (Formal_Typ);
8101 -- Force the definition of the Itype in case of internal function
8102 -- calls within the same or nested scope.
8104 if Is_Subprogram_Or_Generic_Subprogram (E) then
8105 Subp_Decl := Parent (E);
8107 -- The insertion point for an Itype reference should be after
8108 -- the unit declaration node of the subprogram. An exception
8109 -- to this are inherited operations from a parent type in which
8110 -- case the derived type acts as their parent.
8112 if Nkind_In (Subp_Decl, N_Function_Specification,
8113 N_Procedure_Specification)
8115 Subp_Decl := Parent (Subp_Decl);
8118 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8123 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8127 -- If this is an instance of a generic, we need to have extra formals
8130 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8131 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8133 end Create_Extra_Formals;
8135 -----------------------------
8136 -- Enter_Overloaded_Entity --
8137 -----------------------------
8139 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8140 function Matches_Predefined_Op return Boolean;
8141 -- This returns an approximation of whether S matches a predefined
8142 -- operator, based on the operator symbol, and the parameter and result
8143 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8145 ---------------------------
8146 -- Matches_Predefined_Op --
8147 ---------------------------
8149 function Matches_Predefined_Op return Boolean is
8150 Formal_1 : constant Entity_Id := First_Formal (S);
8151 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8152 Op : constant Name_Id := Chars (S);
8153 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8154 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8159 if Present (Formal_2) then
8161 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8164 -- All but "&" and "**" have same-types parameters
8173 if Type_1 /= Type_2 then
8178 -- Check parameter and result types
8186 Is_Boolean_Type (Result_Type)
8187 and then Result_Type = Type_1;
8193 Is_Integer_Type (Result_Type)
8194 and then Result_Type = Type_1;
8202 Is_Numeric_Type (Result_Type)
8203 and then Result_Type = Type_1;
8209 Is_Boolean_Type (Result_Type)
8210 and then not Is_Limited_Type (Type_1);
8218 Is_Boolean_Type (Result_Type)
8219 and then (Is_Array_Type (Type_1)
8220 or else Is_Scalar_Type (Type_1));
8222 when Name_Op_Concat =>
8223 return Is_Array_Type (Result_Type);
8225 when Name_Op_Expon =>
8227 (Is_Integer_Type (Result_Type)
8228 or else Is_Floating_Point_Type (Result_Type))
8229 and then Result_Type = Type_1
8230 and then Type_2 = Standard_Integer;
8233 raise Program_Error;
8246 Is_Numeric_Type (Result_Type)
8247 and then Result_Type = Type_1;
8251 Is_Boolean_Type (Result_Type)
8252 and then Result_Type = Type_1;
8255 raise Program_Error;
8258 end Matches_Predefined_Op;
8262 E : Entity_Id := Current_Entity_In_Scope (S);
8263 C_E : Entity_Id := Current_Entity (S);
8265 -- Start of processing for Enter_Overloaded_Entity
8269 Set_Has_Homonym (E);
8270 Set_Has_Homonym (S);
8273 Set_Is_Immediately_Visible (S);
8274 Set_Scope (S, Current_Scope);
8276 -- Chain new entity if front of homonym in current scope, so that
8277 -- homonyms are contiguous.
8279 if Present (E) and then E /= C_E then
8280 while Homonym (C_E) /= E loop
8281 C_E := Homonym (C_E);
8284 Set_Homonym (C_E, S);
8288 Set_Current_Entity (S);
8293 if Is_Inherited_Operation (S) then
8294 Append_Inherited_Subprogram (S);
8296 Append_Entity (S, Current_Scope);
8299 Set_Public_Status (S);
8301 if Debug_Flag_E then
8302 Write_Str ("New overloaded entity chain: ");
8303 Write_Name (Chars (S));
8306 while Present (E) loop
8307 Write_Str (" "); Write_Int (Int (E));
8314 -- Generate warning for hiding
8317 and then Comes_From_Source (S)
8318 and then In_Extended_Main_Source_Unit (S)
8325 -- Warn unless genuine overloading. Do not emit warning on
8326 -- hiding predefined operators in Standard (these are either an
8327 -- (artifact of our implicit declarations, or simple noise) but
8328 -- keep warning on a operator defined on a local subtype, because
8329 -- of the real danger that different operators may be applied in
8330 -- various parts of the program.
8332 -- Note that if E and S have the same scope, there is never any
8333 -- hiding. Either the two conflict, and the program is illegal,
8334 -- or S is overriding an implicit inherited subprogram.
8336 if Scope (E) /= Scope (S)
8337 and then (not Is_Overloadable (E)
8338 or else Subtype_Conformant (E, S))
8339 and then (Is_Immediately_Visible (E)
8340 or else Is_Potentially_Use_Visible (S))
8342 if Scope (E) = Standard_Standard then
8343 if Nkind (S) = N_Defining_Operator_Symbol
8344 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8346 and then Matches_Predefined_Op
8349 ("declaration of & hides predefined operator?h?", S);
8352 -- E not immediately within Standard
8355 Error_Msg_Sloc := Sloc (E);
8356 Error_Msg_N ("declaration of & hides one #?h?", S);
8361 end Enter_Overloaded_Entity;
8363 -----------------------------
8364 -- Check_Untagged_Equality --
8365 -----------------------------
8367 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8368 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8369 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8373 -- This check applies only if we have a subprogram declaration with an
8374 -- untagged record type.
8376 if Nkind (Decl) /= N_Subprogram_Declaration
8377 or else not Is_Record_Type (Typ)
8378 or else Is_Tagged_Type (Typ)
8383 -- In Ada 2012 case, we will output errors or warnings depending on
8384 -- the setting of debug flag -gnatd.E.
8386 if Ada_Version >= Ada_2012 then
8387 Error_Msg_Warn := Debug_Flag_Dot_EE;
8389 -- In earlier versions of Ada, nothing to do unless we are warning on
8390 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8393 if not Warn_On_Ada_2012_Compatibility then
8398 -- Cases where the type has already been frozen
8400 if Is_Frozen (Typ) then
8402 -- The check applies to a primitive operation, so check that type
8403 -- and equality operation are in the same scope.
8405 if Scope (Typ) /= Current_Scope then
8408 -- If the type is a generic actual (sub)type, the operation is not
8409 -- primitive either because the base type is declared elsewhere.
8411 elsif Is_Generic_Actual_Type (Typ) then
8414 -- Here we have a definite error of declaration after freezing
8417 if Ada_Version >= Ada_2012 then
8419 ("equality operator must be declared before type & is "
8420 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8422 -- In Ada 2012 mode with error turned to warning, output one
8423 -- more warning to warn that the equality operation may not
8424 -- compose. This is the consequence of ignoring the error.
8426 if Error_Msg_Warn then
8427 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8432 ("equality operator must be declared before type& is "
8433 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8436 -- If we are in the package body, we could just move the
8437 -- declaration to the package spec, so add a message saying that.
8439 if In_Package_Body (Scope (Typ)) then
8440 if Ada_Version >= Ada_2012 then
8442 ("\move declaration to package spec<<", Eq_Op);
8445 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8448 -- Otherwise try to find the freezing point for better message.
8451 Obj_Decl := Next (Parent (Typ));
8452 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8453 if Nkind (Obj_Decl) = N_Object_Declaration
8454 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8456 -- Freezing point, output warnings
8458 if Ada_Version >= Ada_2012 then
8460 ("type& is frozen by declaration??", Obj_Decl, Typ);
8462 ("\an equality operator cannot be declared after "
8467 ("type& is frozen by declaration (Ada 2012)?y?",
8470 ("\an equality operator cannot be declared after "
8471 & "this point (Ada 2012)?y?",
8477 -- If we reach generated code for subprogram declaration
8478 -- or body, it is the body that froze the type and the
8479 -- declaration is legal.
8481 elsif Sloc (Obj_Decl) = Sloc (Decl) then
8490 -- Here if type is not frozen yet. It is illegal to have a primitive
8491 -- equality declared in the private part if the type is visible.
8493 elsif not In_Same_List (Parent (Typ), Decl)
8494 and then not Is_Limited_Type (Typ)
8496 -- Shouldn't we give an RM reference here???
8498 if Ada_Version >= Ada_2012 then
8500 ("equality operator appears too late<<", Eq_Op);
8503 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8506 -- No error detected
8511 end Check_Untagged_Equality;
8513 -----------------------------
8514 -- Find_Corresponding_Spec --
8515 -----------------------------
8517 function Find_Corresponding_Spec
8519 Post_Error : Boolean := True) return Entity_Id
8521 Spec : constant Node_Id := Specification (N);
8522 Designator : constant Entity_Id := Defining_Entity (Spec);
8526 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8527 -- Even if fully conformant, a body may depend on a generic actual when
8528 -- the spec does not, or vice versa, in which case they were distinct
8529 -- entities in the generic.
8531 -------------------------------
8532 -- Different_Generic_Profile --
8533 -------------------------------
8535 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8538 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8539 -- Check that the types of corresponding formals have the same
8540 -- generic actual if any. We have to account for subtypes of a
8541 -- generic formal, declared between a spec and a body, which may
8542 -- appear distinct in an instance but matched in the generic, and
8543 -- the subtype may be used either in the spec or the body of the
8544 -- subprogram being checked.
8546 -------------------------
8547 -- Same_Generic_Actual --
8548 -------------------------
8550 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8552 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8553 -- Predicate to check whether S1 is a subtype of S2 in the source
8556 -------------------------
8557 -- Is_Declared_Subtype --
8558 -------------------------
8560 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8562 return Comes_From_Source (Parent (S1))
8563 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8564 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8565 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8566 end Is_Declared_Subtype;
8568 -- Start of processing for Same_Generic_Actual
8571 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8572 or else Is_Declared_Subtype (T1, T2)
8573 or else Is_Declared_Subtype (T2, T1);
8574 end Same_Generic_Actual;
8576 -- Start of processing for Different_Generic_Profile
8579 if not In_Instance then
8582 elsif Ekind (E) = E_Function
8583 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8588 F1 := First_Formal (Designator);
8589 F2 := First_Formal (E);
8590 while Present (F1) loop
8591 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8600 end Different_Generic_Profile;
8602 -- Start of processing for Find_Corresponding_Spec
8605 E := Current_Entity (Designator);
8606 while Present (E) loop
8608 -- We are looking for a matching spec. It must have the same scope,
8609 -- and the same name, and either be type conformant, or be the case
8610 -- of a library procedure spec and its body (which belong to one
8611 -- another regardless of whether they are type conformant or not).
8613 if Scope (E) = Current_Scope then
8614 if Current_Scope = Standard_Standard
8615 or else (Ekind (E) = Ekind (Designator)
8616 and then Type_Conformant (E, Designator))
8618 -- Within an instantiation, we know that spec and body are
8619 -- subtype conformant, because they were subtype conformant in
8620 -- the generic. We choose the subtype-conformant entity here as
8621 -- well, to resolve spurious ambiguities in the instance that
8622 -- were not present in the generic (i.e. when two different
8623 -- types are given the same actual). If we are looking for a
8624 -- spec to match a body, full conformance is expected.
8628 -- Inherit the convention and "ghostness" of the matching
8629 -- spec to ensure proper full and subtype conformance.
8631 Set_Convention (Designator, Convention (E));
8633 -- Skip past subprogram bodies and subprogram renamings that
8634 -- may appear to have a matching spec, but that aren't fully
8635 -- conformant with it. That can occur in cases where an
8636 -- actual type causes unrelated homographs in the instance.
8638 if Nkind_In (N, N_Subprogram_Body,
8639 N_Subprogram_Renaming_Declaration)
8640 and then Present (Homonym (E))
8641 and then not Fully_Conformant (Designator, E)
8645 elsif not Subtype_Conformant (Designator, E) then
8648 elsif Different_Generic_Profile (E) then
8653 -- Ada 2012 (AI05-0165): For internally generated bodies of
8654 -- null procedures locate the internally generated spec. We
8655 -- enforce mode conformance since a tagged type may inherit
8656 -- from interfaces several null primitives which differ only
8657 -- in the mode of the formals.
8659 if not (Comes_From_Source (E))
8660 and then Is_Null_Procedure (E)
8661 and then not Mode_Conformant (Designator, E)
8665 -- For null procedures coming from source that are completions,
8666 -- analysis of the generated body will establish the link.
8668 elsif Comes_From_Source (E)
8669 and then Nkind (Spec) = N_Procedure_Specification
8670 and then Null_Present (Spec)
8674 -- Expression functions can be completions, but cannot be
8675 -- completed by an explicit body.
8677 elsif Comes_From_Source (E)
8678 and then Comes_From_Source (N)
8679 and then Nkind (N) = N_Subprogram_Body
8680 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8681 N_Expression_Function
8683 Error_Msg_Sloc := Sloc (E);
8684 Error_Msg_N ("body conflicts with expression function#", N);
8687 elsif not Has_Completion (E) then
8688 if Nkind (N) /= N_Subprogram_Body_Stub then
8689 Set_Corresponding_Spec (N, E);
8692 Set_Has_Completion (E);
8695 elsif Nkind (Parent (N)) = N_Subunit then
8697 -- If this is the proper body of a subunit, the completion
8698 -- flag is set when analyzing the stub.
8702 -- If E is an internal function with a controlling result that
8703 -- was created for an operation inherited by a null extension,
8704 -- it may be overridden by a body without a previous spec (one
8705 -- more reason why these should be shunned). In that case we
8706 -- remove the generated body if present, because the current
8707 -- one is the explicit overriding.
8709 elsif Ekind (E) = E_Function
8710 and then Ada_Version >= Ada_2005
8711 and then not Comes_From_Source (E)
8712 and then Has_Controlling_Result (E)
8713 and then Is_Null_Extension (Etype (E))
8714 and then Comes_From_Source (Spec)
8716 Set_Has_Completion (E, False);
8719 and then Nkind (Parent (E)) = N_Function_Specification
8722 (Unit_Declaration_Node
8723 (Corresponding_Body (Unit_Declaration_Node (E))));
8727 -- If expansion is disabled, or if the wrapper function has
8728 -- not been generated yet, this a late body overriding an
8729 -- inherited operation, or it is an overriding by some other
8730 -- declaration before the controlling result is frozen. In
8731 -- either case this is a declaration of a new entity.
8737 -- If the body already exists, then this is an error unless
8738 -- the previous declaration is the implicit declaration of a
8739 -- derived subprogram. It is also legal for an instance to
8740 -- contain type conformant overloadable declarations (but the
8741 -- generic declaration may not), per 8.3(26/2).
8743 elsif No (Alias (E))
8744 and then not Is_Intrinsic_Subprogram (E)
8745 and then not In_Instance
8748 Error_Msg_Sloc := Sloc (E);
8750 if Is_Imported (E) then
8752 ("body not allowed for imported subprogram & declared#",
8755 Error_Msg_NE ("duplicate body for & declared#", N, E);
8759 -- Child units cannot be overloaded, so a conformance mismatch
8760 -- between body and a previous spec is an error.
8762 elsif Is_Child_Unit (E)
8764 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8766 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8771 ("body of child unit does not match previous declaration", N);
8779 -- On exit, we know that no previous declaration of subprogram exists
8782 end Find_Corresponding_Spec;
8784 ----------------------
8785 -- Fully_Conformant --
8786 ----------------------
8788 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8791 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8793 end Fully_Conformant;
8795 ----------------------------------
8796 -- Fully_Conformant_Expressions --
8797 ----------------------------------
8799 function Fully_Conformant_Expressions
8800 (Given_E1 : Node_Id;
8801 Given_E2 : Node_Id) return Boolean
8803 E1 : constant Node_Id := Original_Node (Given_E1);
8804 E2 : constant Node_Id := Original_Node (Given_E2);
8805 -- We always test conformance on original nodes, since it is possible
8806 -- for analysis and/or expansion to make things look as though they
8807 -- conform when they do not, e.g. by converting 1+2 into 3.
8809 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8810 renames Fully_Conformant_Expressions;
8812 function FCL (L1, L2 : List_Id) return Boolean;
8813 -- Compare elements of two lists for conformance. Elements have to be
8814 -- conformant, and actuals inserted as default parameters do not match
8815 -- explicit actuals with the same value.
8817 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8818 -- Compare an operator node with a function call
8824 function FCL (L1, L2 : List_Id) return Boolean is
8828 if L1 = No_List then
8834 if L2 = No_List then
8840 -- Compare two lists, skipping rewrite insertions (we want to compare
8841 -- the original trees, not the expanded versions).
8844 if Is_Rewrite_Insertion (N1) then
8846 elsif Is_Rewrite_Insertion (N2) then
8852 elsif not FCE (N1, N2) then
8865 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8866 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8871 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8876 Act := First (Actuals);
8878 if Nkind (Op_Node) in N_Binary_Op then
8879 if not FCE (Left_Opnd (Op_Node), Act) then
8886 return Present (Act)
8887 and then FCE (Right_Opnd (Op_Node), Act)
8888 and then No (Next (Act));
8892 -- Start of processing for Fully_Conformant_Expressions
8895 -- Nonconformant if paren count does not match. Note: if some idiot
8896 -- complains that we don't do this right for more than 3 levels of
8897 -- parentheses, they will be treated with the respect they deserve.
8899 if Paren_Count (E1) /= Paren_Count (E2) then
8902 -- If same entities are referenced, then they are conformant even if
8903 -- they have different forms (RM 8.3.1(19-20)).
8905 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8906 if Present (Entity (E1)) then
8907 return Entity (E1) = Entity (E2)
8909 -- One may be a discriminant that has been replaced by the
8910 -- corresponding discriminal.
8913 (Chars (Entity (E1)) = Chars (Entity (E2))
8914 and then Ekind (Entity (E1)) = E_Discriminant
8915 and then Ekind (Entity (E2)) = E_In_Parameter)
8917 -- The discriminant of a protected type is transformed into
8918 -- a local constant and then into a parameter of a protected
8922 (Ekind (Entity (E1)) = E_Constant
8923 and then Ekind (Entity (E2)) = E_In_Parameter
8924 and then Present (Discriminal_Link (Entity (E1)))
8925 and then Discriminal_Link (Entity (E1)) =
8926 Discriminal_Link (Entity (E2)))
8928 -- AI12-050: The loop variables of quantified expressions match
8929 -- if they have the same identifier, even though they may have
8930 -- different entities.
8933 (Chars (Entity (E1)) = Chars (Entity (E2))
8934 and then Ekind (Entity (E1)) = E_Loop_Parameter
8935 and then Ekind (Entity (E2)) = E_Loop_Parameter)
8937 -- A call to an instantiation of Unchecked_Conversion is
8938 -- rewritten with the name of the generated function created for
8939 -- the instance, and this must be special-cased.
8942 (Ekind (Entity (E1)) = E_Function
8943 and then Is_Intrinsic_Subprogram (Entity (E1))
8944 and then Is_Generic_Instance (Entity (E1))
8945 and then Entity (E2) = Alias (Entity (E1)));
8947 elsif Nkind (E1) = N_Expanded_Name
8948 and then Nkind (E2) = N_Expanded_Name
8949 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8950 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8952 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8955 -- Identifiers in component associations don't always have
8956 -- entities, but their names must conform.
8958 return Nkind (E1) = N_Identifier
8959 and then Nkind (E2) = N_Identifier
8960 and then Chars (E1) = Chars (E2);
8963 elsif Nkind (E1) = N_Character_Literal
8964 and then Nkind (E2) = N_Expanded_Name
8966 return Nkind (Selector_Name (E2)) = N_Character_Literal
8967 and then Chars (E1) = Chars (Selector_Name (E2));
8969 elsif Nkind (E2) = N_Character_Literal
8970 and then Nkind (E1) = N_Expanded_Name
8972 return Nkind (Selector_Name (E1)) = N_Character_Literal
8973 and then Chars (E2) = Chars (Selector_Name (E1));
8975 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8976 return FCO (E1, E2);
8978 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8979 return FCO (E2, E1);
8981 -- Otherwise we must have the same syntactic entity
8983 elsif Nkind (E1) /= Nkind (E2) then
8986 -- At this point, we specialize by node type
8992 FCL (Expressions (E1), Expressions (E2))
8994 FCL (Component_Associations (E1),
8995 Component_Associations (E2));
8998 if Nkind (Expression (E1)) = N_Qualified_Expression
9000 Nkind (Expression (E2)) = N_Qualified_Expression
9002 return FCE (Expression (E1), Expression (E2));
9004 -- Check that the subtype marks and any constraints
9009 Indic1 : constant Node_Id := Expression (E1);
9010 Indic2 : constant Node_Id := Expression (E2);
9015 if Nkind (Indic1) /= N_Subtype_Indication then
9017 Nkind (Indic2) /= N_Subtype_Indication
9018 and then Entity (Indic1) = Entity (Indic2);
9020 elsif Nkind (Indic2) /= N_Subtype_Indication then
9022 Nkind (Indic1) /= N_Subtype_Indication
9023 and then Entity (Indic1) = Entity (Indic2);
9026 if Entity (Subtype_Mark (Indic1)) /=
9027 Entity (Subtype_Mark (Indic2))
9032 Elt1 := First (Constraints (Constraint (Indic1)));
9033 Elt2 := First (Constraints (Constraint (Indic2)));
9034 while Present (Elt1) and then Present (Elt2) loop
9035 if not FCE (Elt1, Elt2) then
9048 when N_Attribute_Reference =>
9050 Attribute_Name (E1) = Attribute_Name (E2)
9051 and then FCL (Expressions (E1), Expressions (E2));
9055 Entity (E1) = Entity (E2)
9056 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9057 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9059 when N_Membership_Test
9063 FCE (Left_Opnd (E1), Left_Opnd (E2))
9065 FCE (Right_Opnd (E1), Right_Opnd (E2));
9067 when N_Case_Expression =>
9073 if not FCE (Expression (E1), Expression (E2)) then
9077 Alt1 := First (Alternatives (E1));
9078 Alt2 := First (Alternatives (E2));
9080 if Present (Alt1) /= Present (Alt2) then
9082 elsif No (Alt1) then
9086 if not FCE (Expression (Alt1), Expression (Alt2))
9087 or else not FCL (Discrete_Choices (Alt1),
9088 Discrete_Choices (Alt2))
9099 when N_Character_Literal =>
9101 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9103 when N_Component_Association =>
9105 FCL (Choices (E1), Choices (E2))
9107 FCE (Expression (E1), Expression (E2));
9109 when N_Explicit_Dereference =>
9111 FCE (Prefix (E1), Prefix (E2));
9113 when N_Extension_Aggregate =>
9115 FCL (Expressions (E1), Expressions (E2))
9116 and then Null_Record_Present (E1) =
9117 Null_Record_Present (E2)
9118 and then FCL (Component_Associations (E1),
9119 Component_Associations (E2));
9121 when N_Function_Call =>
9123 FCE (Name (E1), Name (E2))
9125 FCL (Parameter_Associations (E1),
9126 Parameter_Associations (E2));
9128 when N_If_Expression =>
9130 FCL (Expressions (E1), Expressions (E2));
9132 when N_Indexed_Component =>
9134 FCE (Prefix (E1), Prefix (E2))
9136 FCL (Expressions (E1), Expressions (E2));
9138 when N_Integer_Literal =>
9139 return (Intval (E1) = Intval (E2));
9144 when N_Operator_Symbol =>
9146 Chars (E1) = Chars (E2);
9148 when N_Others_Choice =>
9151 when N_Parameter_Association =>
9153 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9154 and then FCE (Explicit_Actual_Parameter (E1),
9155 Explicit_Actual_Parameter (E2));
9157 when N_Qualified_Expression
9159 | N_Unchecked_Type_Conversion
9162 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9164 FCE (Expression (E1), Expression (E2));
9166 when N_Quantified_Expression =>
9167 if not FCE (Condition (E1), Condition (E2)) then
9171 if Present (Loop_Parameter_Specification (E1))
9172 and then Present (Loop_Parameter_Specification (E2))
9175 L1 : constant Node_Id :=
9176 Loop_Parameter_Specification (E1);
9177 L2 : constant Node_Id :=
9178 Loop_Parameter_Specification (E2);
9182 Reverse_Present (L1) = Reverse_Present (L2)
9184 FCE (Defining_Identifier (L1),
9185 Defining_Identifier (L2))
9187 FCE (Discrete_Subtype_Definition (L1),
9188 Discrete_Subtype_Definition (L2));
9191 elsif Present (Iterator_Specification (E1))
9192 and then Present (Iterator_Specification (E2))
9195 I1 : constant Node_Id := Iterator_Specification (E1);
9196 I2 : constant Node_Id := Iterator_Specification (E2);
9200 FCE (Defining_Identifier (I1),
9201 Defining_Identifier (I2))
9203 Of_Present (I1) = Of_Present (I2)
9205 Reverse_Present (I1) = Reverse_Present (I2)
9206 and then FCE (Name (I1), Name (I2))
9207 and then FCE (Subtype_Indication (I1),
9208 Subtype_Indication (I2));
9211 -- The quantified expressions used different specifications to
9212 -- walk their respective ranges.
9220 FCE (Low_Bound (E1), Low_Bound (E2))
9222 FCE (High_Bound (E1), High_Bound (E2));
9224 when N_Real_Literal =>
9225 return (Realval (E1) = Realval (E2));
9227 when N_Selected_Component =>
9229 FCE (Prefix (E1), Prefix (E2))
9231 FCE (Selector_Name (E1), Selector_Name (E2));
9235 FCE (Prefix (E1), Prefix (E2))
9237 FCE (Discrete_Range (E1), Discrete_Range (E2));
9239 when N_String_Literal =>
9241 S1 : constant String_Id := Strval (E1);
9242 S2 : constant String_Id := Strval (E2);
9243 L1 : constant Nat := String_Length (S1);
9244 L2 : constant Nat := String_Length (S2);
9251 for J in 1 .. L1 loop
9252 if Get_String_Char (S1, J) /=
9253 Get_String_Char (S2, J)
9265 Entity (E1) = Entity (E2)
9267 FCE (Right_Opnd (E1), Right_Opnd (E2));
9269 -- All other node types cannot appear in this context. Strictly
9270 -- we should raise a fatal internal error. Instead we just ignore
9271 -- the nodes. This means that if anyone makes a mistake in the
9272 -- expander and mucks an expression tree irretrievably, the result
9273 -- will be a failure to detect a (probably very obscure) case
9274 -- of non-conformance, which is better than bombing on some
9275 -- case where two expressions do in fact conform.
9281 end Fully_Conformant_Expressions;
9283 ----------------------------------------
9284 -- Fully_Conformant_Discrete_Subtypes --
9285 ----------------------------------------
9287 function Fully_Conformant_Discrete_Subtypes
9288 (Given_S1 : Node_Id;
9289 Given_S2 : Node_Id) return Boolean
9291 S1 : constant Node_Id := Original_Node (Given_S1);
9292 S2 : constant Node_Id := Original_Node (Given_S2);
9294 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9295 -- Special-case for a bound given by a discriminant, which in the body
9296 -- is replaced with the discriminal of the enclosing type.
9298 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9299 -- Check both bounds
9301 -----------------------
9302 -- Conforming_Bounds --
9303 -----------------------
9305 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9307 if Is_Entity_Name (B1)
9308 and then Is_Entity_Name (B2)
9309 and then Ekind (Entity (B1)) = E_Discriminant
9311 return Chars (B1) = Chars (B2);
9314 return Fully_Conformant_Expressions (B1, B2);
9316 end Conforming_Bounds;
9318 -----------------------
9319 -- Conforming_Ranges --
9320 -----------------------
9322 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9325 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9327 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9328 end Conforming_Ranges;
9330 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9333 if Nkind (S1) /= Nkind (S2) then
9336 elsif Is_Entity_Name (S1) then
9337 return Entity (S1) = Entity (S2);
9339 elsif Nkind (S1) = N_Range then
9340 return Conforming_Ranges (S1, S2);
9342 elsif Nkind (S1) = N_Subtype_Indication then
9344 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9347 (Range_Expression (Constraint (S1)),
9348 Range_Expression (Constraint (S2)));
9352 end Fully_Conformant_Discrete_Subtypes;
9354 --------------------
9355 -- Install_Entity --
9356 --------------------
9358 procedure Install_Entity (E : Entity_Id) is
9359 Prev : constant Entity_Id := Current_Entity (E);
9361 Set_Is_Immediately_Visible (E);
9362 Set_Current_Entity (E);
9363 Set_Homonym (E, Prev);
9366 ---------------------
9367 -- Install_Formals --
9368 ---------------------
9370 procedure Install_Formals (Id : Entity_Id) is
9373 F := First_Formal (Id);
9374 while Present (F) loop
9378 end Install_Formals;
9380 -----------------------------
9381 -- Is_Interface_Conformant --
9382 -----------------------------
9384 function Is_Interface_Conformant
9385 (Tagged_Type : Entity_Id;
9386 Iface_Prim : Entity_Id;
9387 Prim : Entity_Id) return Boolean
9389 -- The operation may in fact be an inherited (implicit) operation
9390 -- rather than the original interface primitive, so retrieve the
9391 -- ultimate ancestor.
9393 Iface : constant Entity_Id :=
9394 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9395 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9397 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9398 -- Return the controlling formal of Prim
9400 ------------------------
9401 -- Controlling_Formal --
9402 ------------------------
9404 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9408 E := First_Entity (Prim);
9409 while Present (E) loop
9410 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9418 end Controlling_Formal;
9422 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9423 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9425 -- Start of processing for Is_Interface_Conformant
9428 pragma Assert (Is_Subprogram (Iface_Prim)
9429 and then Is_Subprogram (Prim)
9430 and then Is_Dispatching_Operation (Iface_Prim)
9431 and then Is_Dispatching_Operation (Prim));
9433 pragma Assert (Is_Interface (Iface)
9434 or else (Present (Alias (Iface_Prim))
9437 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9439 if Prim = Iface_Prim
9440 or else not Is_Subprogram (Prim)
9441 or else Ekind (Prim) /= Ekind (Iface_Prim)
9442 or else not Is_Dispatching_Operation (Prim)
9443 or else Scope (Prim) /= Scope (Tagged_Type)
9445 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9446 or else not Primitive_Names_Match (Iface_Prim, Prim)
9450 -- The mode of the controlling formals must match
9452 elsif Present (Iface_Ctrl_F)
9453 and then Present (Prim_Ctrl_F)
9454 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9458 -- Case of a procedure, or a function whose result type matches the
9459 -- result type of the interface primitive, or a function that has no
9460 -- controlling result (I or access I).
9462 elsif Ekind (Iface_Prim) = E_Procedure
9463 or else Etype (Prim) = Etype (Iface_Prim)
9464 or else not Has_Controlling_Result (Prim)
9466 return Type_Conformant
9467 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9469 -- Case of a function returning an interface, or an access to one. Check
9470 -- that the return types correspond.
9472 elsif Implements_Interface (Typ, Iface) then
9473 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9475 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9480 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9481 Skip_Controlling_Formals => True);
9487 end Is_Interface_Conformant;
9489 ---------------------------------
9490 -- Is_Non_Overriding_Operation --
9491 ---------------------------------
9493 function Is_Non_Overriding_Operation
9494 (Prev_E : Entity_Id;
9495 New_E : Entity_Id) return Boolean
9499 G_Typ : Entity_Id := Empty;
9501 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9502 -- If F_Type is a derived type associated with a generic actual subtype,
9503 -- then return its Generic_Parent_Type attribute, else return Empty.
9505 function Types_Correspond
9506 (P_Type : Entity_Id;
9507 N_Type : Entity_Id) return Boolean;
9508 -- Returns true if and only if the types (or designated types in the
9509 -- case of anonymous access types) are the same or N_Type is derived
9510 -- directly or indirectly from P_Type.
9512 -----------------------------
9513 -- Get_Generic_Parent_Type --
9514 -----------------------------
9516 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9522 if Is_Derived_Type (F_Typ)
9523 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9525 -- The tree must be traversed to determine the parent subtype in
9526 -- the generic unit, which unfortunately isn't always available
9527 -- via semantic attributes. ??? (Note: The use of Original_Node
9528 -- is needed for cases where a full derived type has been
9531 -- If the parent type is a scalar type, the derivation creates
9532 -- an anonymous base type for it, and the source type is its
9535 if Is_Scalar_Type (F_Typ)
9536 and then not Comes_From_Source (F_Typ)
9540 (Original_Node (Parent (First_Subtype (F_Typ))));
9542 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9544 if Nkind (Defn) = N_Derived_Type_Definition then
9545 Indic := Subtype_Indication (Defn);
9547 if Nkind (Indic) = N_Subtype_Indication then
9548 G_Typ := Entity (Subtype_Mark (Indic));
9550 G_Typ := Entity (Indic);
9553 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9554 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9556 return Generic_Parent_Type (Parent (G_Typ));
9562 end Get_Generic_Parent_Type;
9564 ----------------------
9565 -- Types_Correspond --
9566 ----------------------
9568 function Types_Correspond
9569 (P_Type : Entity_Id;
9570 N_Type : Entity_Id) return Boolean
9572 Prev_Type : Entity_Id := Base_Type (P_Type);
9573 New_Type : Entity_Id := Base_Type (N_Type);
9576 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9577 Prev_Type := Designated_Type (Prev_Type);
9580 if Ekind (New_Type) = E_Anonymous_Access_Type then
9581 New_Type := Designated_Type (New_Type);
9584 if Prev_Type = New_Type then
9587 elsif not Is_Class_Wide_Type (New_Type) then
9588 while Etype (New_Type) /= New_Type loop
9589 New_Type := Etype (New_Type);
9591 if New_Type = Prev_Type then
9597 end Types_Correspond;
9599 -- Start of processing for Is_Non_Overriding_Operation
9602 -- In the case where both operations are implicit derived subprograms
9603 -- then neither overrides the other. This can only occur in certain
9604 -- obscure cases (e.g., derivation from homographs created in a generic
9607 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9610 elsif Ekind (Current_Scope) = E_Package
9611 and then Is_Generic_Instance (Current_Scope)
9612 and then In_Private_Part (Current_Scope)
9613 and then Comes_From_Source (New_E)
9615 -- We examine the formals and result type of the inherited operation,
9616 -- to determine whether their type is derived from (the instance of)
9617 -- a generic type. The first such formal or result type is the one
9620 Formal := First_Formal (Prev_E);
9622 while Present (Formal) loop
9623 F_Typ := Base_Type (Etype (Formal));
9625 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9626 F_Typ := Designated_Type (F_Typ);
9629 G_Typ := Get_Generic_Parent_Type (F_Typ);
9630 exit when Present (G_Typ);
9632 Next_Formal (Formal);
9635 -- If the function dispatches on result check the result type
9637 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9638 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9645 -- If the generic type is a private type, then the original operation
9646 -- was not overriding in the generic, because there was no primitive
9647 -- operation to override.
9649 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9650 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9651 N_Formal_Private_Type_Definition
9655 -- The generic parent type is the ancestor of a formal derived
9656 -- type declaration. We need to check whether it has a primitive
9657 -- operation that should be overridden by New_E in the generic.
9661 P_Formal : Entity_Id;
9662 N_Formal : Entity_Id;
9666 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9669 while Present (Prim_Elt) loop
9670 P_Prim := Node (Prim_Elt);
9672 if Chars (P_Prim) = Chars (New_E)
9673 and then Ekind (P_Prim) = Ekind (New_E)
9675 P_Formal := First_Formal (P_Prim);
9676 N_Formal := First_Formal (New_E);
9677 while Present (P_Formal) and then Present (N_Formal) loop
9678 P_Typ := Etype (P_Formal);
9679 N_Typ := Etype (N_Formal);
9681 if not Types_Correspond (P_Typ, N_Typ) then
9685 Next_Entity (P_Formal);
9686 Next_Entity (N_Formal);
9689 -- Found a matching primitive operation belonging to the
9690 -- formal ancestor type, so the new subprogram is
9694 and then No (N_Formal)
9695 and then (Ekind (New_E) /= E_Function
9698 (Etype (P_Prim), Etype (New_E)))
9704 Next_Elmt (Prim_Elt);
9707 -- If no match found, then the new subprogram does not override
9708 -- in the generic (nor in the instance).
9710 -- If the type in question is not abstract, and the subprogram
9711 -- is, this will be an error if the new operation is in the
9712 -- private part of the instance. Emit a warning now, which will
9713 -- make the subsequent error message easier to understand.
9715 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9716 and then Is_Abstract_Subprogram (Prev_E)
9717 and then In_Private_Part (Current_Scope)
9719 Error_Msg_Node_2 := F_Typ;
9721 ("private operation& in generic unit does not override "
9722 & "any primitive operation of& (RM 12.3 (18))??",
9732 end Is_Non_Overriding_Operation;
9734 -------------------------------------
9735 -- List_Inherited_Pre_Post_Aspects --
9736 -------------------------------------
9738 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9740 if Opt.List_Inherited_Aspects
9741 and then Is_Subprogram_Or_Generic_Subprogram (E)
9744 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9749 for Index in Subps'Range loop
9750 Items := Contract (Subps (Index));
9752 if Present (Items) then
9753 Prag := Pre_Post_Conditions (Items);
9754 while Present (Prag) loop
9755 Error_Msg_Sloc := Sloc (Prag);
9757 if Class_Present (Prag)
9758 and then not Split_PPC (Prag)
9760 if Pragma_Name (Prag) = Name_Precondition then
9762 ("info: & inherits `Pre''Class` aspect from "
9766 ("info: & inherits `Post''Class` aspect from "
9771 Prag := Next_Pragma (Prag);
9777 end List_Inherited_Pre_Post_Aspects;
9779 ------------------------------
9780 -- Make_Inequality_Operator --
9781 ------------------------------
9783 -- S is the defining identifier of an equality operator. We build a
9784 -- subprogram declaration with the right signature. This operation is
9785 -- intrinsic, because it is always expanded as the negation of the
9786 -- call to the equality function.
9788 procedure Make_Inequality_Operator (S : Entity_Id) is
9789 Loc : constant Source_Ptr := Sloc (S);
9792 Op_Name : Entity_Id;
9794 FF : constant Entity_Id := First_Formal (S);
9795 NF : constant Entity_Id := Next_Formal (FF);
9798 -- Check that equality was properly defined, ignore call if not
9805 A : constant Entity_Id :=
9806 Make_Defining_Identifier (Sloc (FF),
9807 Chars => Chars (FF));
9809 B : constant Entity_Id :=
9810 Make_Defining_Identifier (Sloc (NF),
9811 Chars => Chars (NF));
9814 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9816 Formals := New_List (
9817 Make_Parameter_Specification (Loc,
9818 Defining_Identifier => A,
9820 New_Occurrence_Of (Etype (First_Formal (S)),
9821 Sloc (Etype (First_Formal (S))))),
9823 Make_Parameter_Specification (Loc,
9824 Defining_Identifier => B,
9826 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9827 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9830 Make_Subprogram_Declaration (Loc,
9832 Make_Function_Specification (Loc,
9833 Defining_Unit_Name => Op_Name,
9834 Parameter_Specifications => Formals,
9835 Result_Definition =>
9836 New_Occurrence_Of (Standard_Boolean, Loc)));
9838 -- Insert inequality right after equality if it is explicit or after
9839 -- the derived type when implicit. These entities are created only
9840 -- for visibility purposes, and eventually replaced in the course
9841 -- of expansion, so they do not need to be attached to the tree and
9842 -- seen by the back-end. Keeping them internal also avoids spurious
9843 -- freezing problems. The declaration is inserted in the tree for
9844 -- analysis, and removed afterwards. If the equality operator comes
9845 -- from an explicit declaration, attach the inequality immediately
9846 -- after. Else the equality is inherited from a derived type
9847 -- declaration, so insert inequality after that declaration.
9849 if No (Alias (S)) then
9850 Insert_After (Unit_Declaration_Node (S), Decl);
9851 elsif Is_List_Member (Parent (S)) then
9852 Insert_After (Parent (S), Decl);
9854 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9857 Mark_Rewrite_Insertion (Decl);
9858 Set_Is_Intrinsic_Subprogram (Op_Name);
9861 Set_Has_Completion (Op_Name);
9862 Set_Corresponding_Equality (Op_Name, S);
9863 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9865 end Make_Inequality_Operator;
9867 ----------------------
9868 -- May_Need_Actuals --
9869 ----------------------
9871 procedure May_Need_Actuals (Fun : Entity_Id) is
9876 F := First_Formal (Fun);
9878 while Present (F) loop
9879 if No (Default_Value (F)) then
9887 Set_Needs_No_Actuals (Fun, B);
9888 end May_Need_Actuals;
9890 ---------------------
9891 -- Mode_Conformant --
9892 ---------------------
9894 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9897 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9899 end Mode_Conformant;
9901 ---------------------------
9902 -- New_Overloaded_Entity --
9903 ---------------------------
9905 procedure New_Overloaded_Entity
9907 Derived_Type : Entity_Id := Empty)
9909 Overridden_Subp : Entity_Id := Empty;
9910 -- Set if the current scope has an operation that is type-conformant
9911 -- with S, and becomes hidden by S.
9913 Is_Primitive_Subp : Boolean;
9914 -- Set to True if the new subprogram is primitive
9917 -- Entity that S overrides
9919 procedure Check_For_Primitive_Subprogram
9920 (Is_Primitive : out Boolean;
9921 Is_Overriding : Boolean := False);
9922 -- If the subprogram being analyzed is a primitive operation of the type
9923 -- of a formal or result, set the Has_Primitive_Operations flag on the
9924 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9925 -- corresponding flag on the entity itself for later use.
9927 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9928 -- True if a) E is a subprogram whose first formal is a concurrent type
9929 -- defined in the scope of E that has some entry or subprogram whose
9930 -- profile matches E, or b) E is an internally built dispatching
9931 -- subprogram of a protected type and there is a matching subprogram
9932 -- defined in the enclosing scope of the protected type, or c) E is
9933 -- an entry of a synchronized type and a matching procedure has been
9934 -- previously defined in the enclosing scope of the synchronized type.
9936 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9937 -- Check that E is declared in the private part of the current package,
9938 -- or in the package body, where it may hide a previous declaration.
9939 -- We can't use In_Private_Part by itself because this flag is also
9940 -- set when freezing entities, so we must examine the place of the
9941 -- declaration in the tree, and recognize wrapper packages as well.
9943 function Is_Overriding_Alias
9945 New_E : Entity_Id) return Boolean;
9946 -- Check whether new subprogram and old subprogram are both inherited
9947 -- from subprograms that have distinct dispatch table entries. This can
9948 -- occur with derivations from instances with accidental homonyms. The
9949 -- function is conservative given that the converse is only true within
9950 -- instances that contain accidental overloadings.
9952 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9953 -- Report conflict between entities S and E
9955 ------------------------------------
9956 -- Check_For_Primitive_Subprogram --
9957 ------------------------------------
9959 procedure Check_For_Primitive_Subprogram
9960 (Is_Primitive : out Boolean;
9961 Is_Overriding : Boolean := False)
9967 function Visible_Part_Type (T : Entity_Id) return Boolean;
9968 -- Returns true if T is declared in the visible part of the current
9969 -- package scope; otherwise returns false. Assumes that T is declared
9972 procedure Check_Private_Overriding (T : Entity_Id);
9973 -- Checks that if a primitive abstract subprogram of a visible
9974 -- abstract type is declared in a private part, then it must override
9975 -- an abstract subprogram declared in the visible part. Also checks
9976 -- that if a primitive function with a controlling result is declared
9977 -- in a private part, then it must override a function declared in
9978 -- the visible part.
9980 ------------------------------
9981 -- Check_Private_Overriding --
9982 ------------------------------
9984 procedure Check_Private_Overriding (T : Entity_Id) is
9985 function Overrides_Private_Part_Op return Boolean;
9986 -- This detects the special case where the overriding subprogram
9987 -- is overriding a subprogram that was declared in the same
9988 -- private part. That case is illegal by 3.9.3(10).
9990 function Overrides_Visible_Function
9991 (Partial_View : Entity_Id) return Boolean;
9992 -- True if S overrides a function in the visible part. The
9993 -- overridden function could be explicitly or implicitly declared.
9995 -------------------------------
9996 -- Overrides_Private_Part_Op --
9997 -------------------------------
9999 function Overrides_Private_Part_Op return Boolean is
10000 Over_Decl : constant Node_Id :=
10001 Unit_Declaration_Node (Overridden_Operation (S));
10002 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10005 pragma Assert (Is_Overriding);
10007 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10009 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10011 return In_Same_List (Over_Decl, Subp_Decl);
10012 end Overrides_Private_Part_Op;
10014 --------------------------------
10015 -- Overrides_Visible_Function --
10016 --------------------------------
10018 function Overrides_Visible_Function
10019 (Partial_View : Entity_Id) return Boolean
10022 if not Is_Overriding or else not Has_Homonym (S) then
10026 if not Present (Partial_View) then
10030 -- Search through all the homonyms H of S in the current
10031 -- package spec, and return True if we find one that matches.
10032 -- Note that Parent (H) will be the declaration of the
10033 -- partial view of T for a match.
10036 H : Entity_Id := S;
10040 exit when not Present (H) or else Scope (H) /= Scope (S);
10044 N_Private_Extension_Declaration,
10045 N_Private_Type_Declaration)
10046 and then Defining_Identifier (Parent (H)) = Partial_View
10054 end Overrides_Visible_Function;
10056 -- Start of processing for Check_Private_Overriding
10059 if Is_Package_Or_Generic_Package (Current_Scope)
10060 and then In_Private_Part (Current_Scope)
10061 and then Visible_Part_Type (T)
10062 and then not In_Instance
10064 if Is_Abstract_Type (T)
10065 and then Is_Abstract_Subprogram (S)
10066 and then (not Is_Overriding
10067 or else not Is_Abstract_Subprogram (E)
10068 or else Overrides_Private_Part_Op)
10071 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10074 elsif Ekind (S) = E_Function then
10076 Partial_View : constant Entity_Id :=
10077 Incomplete_Or_Partial_View (T);
10080 if not Overrides_Visible_Function (Partial_View) then
10082 -- Here, S is "function ... return T;" declared in
10083 -- the private part, not overriding some visible
10084 -- operation. That's illegal in the tagged case
10085 -- (but not if the private type is untagged).
10087 if ((Present (Partial_View)
10088 and then Is_Tagged_Type (Partial_View))
10089 or else (not Present (Partial_View)
10090 and then Is_Tagged_Type (T)))
10091 and then T = Base_Type (Etype (S))
10094 ("private function with tagged result must"
10095 & " override visible-part function", S);
10097 ("\move subprogram to the visible part"
10098 & " (RM 3.9.3(10))", S);
10100 -- AI05-0073: extend this test to the case of a
10101 -- function with a controlling access result.
10103 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10104 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10106 not Is_Class_Wide_Type
10107 (Designated_Type (Etype (S)))
10108 and then Ada_Version >= Ada_2012
10111 ("private function with controlling access "
10112 & "result must override visible-part function",
10115 ("\move subprogram to the visible part"
10116 & " (RM 3.9.3(10))", S);
10122 end Check_Private_Overriding;
10124 -----------------------
10125 -- Visible_Part_Type --
10126 -----------------------
10128 function Visible_Part_Type (T : Entity_Id) return Boolean is
10129 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10132 -- If the entity is a private type, then it must be declared in a
10135 if Ekind (T) in Private_Kind then
10138 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10141 elsif Is_List_Member (Declaration_Node (T))
10142 and then List_Containing (Declaration_Node (T)) =
10143 Visible_Declarations (Specification (P))
10150 end Visible_Part_Type;
10152 -- Start of processing for Check_For_Primitive_Subprogram
10155 Is_Primitive := False;
10157 if not Comes_From_Source (S) then
10160 -- If subprogram is at library level, it is not primitive operation
10162 elsif Current_Scope = Standard_Standard then
10165 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10166 and then not In_Package_Body (Current_Scope))
10167 or else Is_Overriding
10169 -- For function, check return type
10171 if Ekind (S) = E_Function then
10172 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10173 F_Typ := Designated_Type (Etype (S));
10175 F_Typ := Etype (S);
10178 B_Typ := Base_Type (F_Typ);
10180 if Scope (B_Typ) = Current_Scope
10181 and then not Is_Class_Wide_Type (B_Typ)
10182 and then not Is_Generic_Type (B_Typ)
10184 Is_Primitive := True;
10185 Set_Has_Primitive_Operations (B_Typ);
10186 Set_Is_Primitive (S);
10187 Check_Private_Overriding (B_Typ);
10189 -- The Ghost policy in effect at the point of declaration
10190 -- or a tagged type and a primitive operation must match
10191 -- (SPARK RM 6.9(16)).
10193 Check_Ghost_Primitive (S, B_Typ);
10197 -- For all subprograms, check formals
10199 Formal := First_Formal (S);
10200 while Present (Formal) loop
10201 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10202 F_Typ := Designated_Type (Etype (Formal));
10204 F_Typ := Etype (Formal);
10207 B_Typ := Base_Type (F_Typ);
10209 if Ekind (B_Typ) = E_Access_Subtype then
10210 B_Typ := Base_Type (B_Typ);
10213 if Scope (B_Typ) = Current_Scope
10214 and then not Is_Class_Wide_Type (B_Typ)
10215 and then not Is_Generic_Type (B_Typ)
10217 Is_Primitive := True;
10218 Set_Is_Primitive (S);
10219 Set_Has_Primitive_Operations (B_Typ);
10220 Check_Private_Overriding (B_Typ);
10222 -- The Ghost policy in effect at the point of declaration
10223 -- of a tagged type and a primitive operation must match
10224 -- (SPARK RM 6.9(16)).
10226 Check_Ghost_Primitive (S, B_Typ);
10229 Next_Formal (Formal);
10232 -- Special case: An equality function can be redefined for a type
10233 -- occurring in a declarative part, and won't otherwise be treated as
10234 -- a primitive because it doesn't occur in a package spec and doesn't
10235 -- override an inherited subprogram. It's important that we mark it
10236 -- primitive so it can be returned by Collect_Primitive_Operations
10237 -- and be used in composing the equality operation of later types
10238 -- that have a component of the type.
10240 elsif Chars (S) = Name_Op_Eq
10241 and then Etype (S) = Standard_Boolean
10243 B_Typ := Base_Type (Etype (First_Formal (S)));
10245 if Scope (B_Typ) = Current_Scope
10247 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10248 and then not Is_Limited_Type (B_Typ)
10250 Is_Primitive := True;
10251 Set_Is_Primitive (S);
10252 Set_Has_Primitive_Operations (B_Typ);
10253 Check_Private_Overriding (B_Typ);
10255 -- The Ghost policy in effect at the point of declaration of a
10256 -- tagged type and a primitive operation must match
10257 -- (SPARK RM 6.9(16)).
10259 Check_Ghost_Primitive (S, B_Typ);
10262 end Check_For_Primitive_Subprogram;
10264 --------------------------------------
10265 -- Has_Matching_Entry_Or_Subprogram --
10266 --------------------------------------
10268 function Has_Matching_Entry_Or_Subprogram
10269 (E : Entity_Id) return Boolean
10271 function Check_Conforming_Parameters
10272 (E1_Param : Node_Id;
10273 E2_Param : Node_Id) return Boolean;
10274 -- Starting from the given parameters, check that all the parameters
10275 -- of two entries or subprograms are subtype conformant. Used to skip
10276 -- the check on the controlling argument.
10278 function Matching_Entry_Or_Subprogram
10279 (Conc_Typ : Entity_Id;
10280 Subp : Entity_Id) return Entity_Id;
10281 -- Return the first entry or subprogram of the given concurrent type
10282 -- whose name matches the name of Subp and has a profile conformant
10283 -- with Subp; return Empty if not found.
10285 function Matching_Dispatching_Subprogram
10286 (Conc_Typ : Entity_Id;
10287 Ent : Entity_Id) return Entity_Id;
10288 -- Return the first dispatching primitive of Conc_Type defined in the
10289 -- enclosing scope of Conc_Type (i.e. before the full definition of
10290 -- this concurrent type) whose name matches the entry Ent and has a
10291 -- profile conformant with the profile of the corresponding (not yet
10292 -- built) dispatching primitive of Ent; return Empty if not found.
10294 function Matching_Original_Protected_Subprogram
10295 (Prot_Typ : Entity_Id;
10296 Subp : Entity_Id) return Entity_Id;
10297 -- Return the first subprogram defined in the enclosing scope of
10298 -- Prot_Typ (before the full definition of this protected type)
10299 -- whose name matches the original name of Subp and has a profile
10300 -- conformant with the profile of Subp; return Empty if not found.
10302 ---------------------------------
10303 -- Check_Conforming_Parameters --
10304 ---------------------------------
10306 function Check_Conforming_Parameters
10307 (E1_Param : Node_Id;
10308 E2_Param : Node_Id) return Boolean
10310 Param_E1 : Node_Id := E1_Param;
10311 Param_E2 : Node_Id := E2_Param;
10314 while Present (Param_E1) and then Present (Param_E2) loop
10315 if Ekind (Defining_Identifier (Param_E1)) /=
10316 Ekind (Defining_Identifier (Param_E2))
10319 (Find_Parameter_Type (Param_E1),
10320 Find_Parameter_Type (Param_E2),
10321 Subtype_Conformant)
10330 -- The candidate is not valid if one of the two lists contains
10331 -- more parameters than the other
10333 return No (Param_E1) and then No (Param_E2);
10334 end Check_Conforming_Parameters;
10336 ----------------------------------
10337 -- Matching_Entry_Or_Subprogram --
10338 ----------------------------------
10340 function Matching_Entry_Or_Subprogram
10341 (Conc_Typ : Entity_Id;
10342 Subp : Entity_Id) return Entity_Id
10347 E := First_Entity (Conc_Typ);
10348 while Present (E) loop
10349 if Chars (Subp) = Chars (E)
10350 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10352 Check_Conforming_Parameters
10353 (First (Parameter_Specifications (Parent (E))),
10354 Next (First (Parameter_Specifications (Parent (Subp)))))
10363 end Matching_Entry_Or_Subprogram;
10365 -------------------------------------
10366 -- Matching_Dispatching_Subprogram --
10367 -------------------------------------
10369 function Matching_Dispatching_Subprogram
10370 (Conc_Typ : Entity_Id;
10371 Ent : Entity_Id) return Entity_Id
10376 -- Search for entities in the enclosing scope of this synchonized
10379 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10380 Push_Scope (Scope (Conc_Typ));
10381 E := Current_Entity_In_Scope (Ent);
10384 while Present (E) loop
10385 if Scope (E) = Scope (Conc_Typ)
10386 and then Comes_From_Source (E)
10387 and then Ekind (E) = E_Procedure
10388 and then Present (First_Entity (E))
10389 and then Is_Controlling_Formal (First_Entity (E))
10390 and then Etype (First_Entity (E)) = Conc_Typ
10392 Check_Conforming_Parameters
10393 (First (Parameter_Specifications (Parent (Ent))),
10394 Next (First (Parameter_Specifications (Parent (E)))))
10403 end Matching_Dispatching_Subprogram;
10405 --------------------------------------------
10406 -- Matching_Original_Protected_Subprogram --
10407 --------------------------------------------
10409 function Matching_Original_Protected_Subprogram
10410 (Prot_Typ : Entity_Id;
10411 Subp : Entity_Id) return Entity_Id
10413 ICF : constant Boolean :=
10414 Is_Controlling_Formal (First_Entity (Subp));
10418 -- Temporarily decorate the first parameter of Subp as controlling
10419 -- formal, required to invoke Subtype_Conformant.
10421 Set_Is_Controlling_Formal (First_Entity (Subp));
10424 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10426 while Present (E) loop
10427 if Scope (E) = Scope (Prot_Typ)
10428 and then Comes_From_Source (E)
10429 and then Ekind (Subp) = Ekind (E)
10430 and then Present (First_Entity (E))
10431 and then Is_Controlling_Formal (First_Entity (E))
10432 and then Etype (First_Entity (E)) = Prot_Typ
10433 and then Subtype_Conformant (Subp, E,
10434 Skip_Controlling_Formals => True)
10436 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10443 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10446 end Matching_Original_Protected_Subprogram;
10448 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10451 -- Case 1: E is a subprogram whose first formal is a concurrent type
10452 -- defined in the scope of E that has an entry or subprogram whose
10453 -- profile matches E.
10455 if Comes_From_Source (E)
10456 and then Is_Subprogram (E)
10457 and then Present (First_Entity (E))
10458 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10461 Scope (Corresponding_Concurrent_Type
10462 (Etype (First_Entity (E))))
10465 (Matching_Entry_Or_Subprogram
10466 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10469 Report_Conflict (E,
10470 Matching_Entry_Or_Subprogram
10471 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10476 -- Case 2: E is an internally built dispatching subprogram of a
10477 -- protected type and there is a subprogram defined in the enclosing
10478 -- scope of the protected type that has the original name of E and
10479 -- its profile is conformant with the profile of E. We check the
10480 -- name of the original protected subprogram associated with E since
10481 -- the expander builds dispatching primitives of protected functions
10482 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10484 elsif not Comes_From_Source (E)
10485 and then Is_Subprogram (E)
10486 and then Present (First_Entity (E))
10487 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10488 and then Present (Original_Protected_Subprogram (E))
10491 (Matching_Original_Protected_Subprogram
10492 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10495 Report_Conflict (E,
10496 Matching_Original_Protected_Subprogram
10497 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10501 -- Case 3: E is an entry of a synchronized type and a matching
10502 -- procedure has been previously defined in the enclosing scope
10503 -- of the synchronized type.
10505 elsif Comes_From_Source (E)
10506 and then Ekind (E) = E_Entry
10508 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10510 Report_Conflict (E,
10511 Matching_Dispatching_Subprogram (Current_Scope, E));
10516 end Has_Matching_Entry_Or_Subprogram;
10518 ----------------------------
10519 -- Is_Private_Declaration --
10520 ----------------------------
10522 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10523 Decl : constant Node_Id := Unit_Declaration_Node (E);
10524 Priv_Decls : List_Id;
10527 if Is_Package_Or_Generic_Package (Current_Scope)
10528 and then In_Private_Part (Current_Scope)
10531 Private_Declarations (Package_Specification (Current_Scope));
10533 return In_Package_Body (Current_Scope)
10535 (Is_List_Member (Decl)
10536 and then List_Containing (Decl) = Priv_Decls)
10537 or else (Nkind (Parent (Decl)) = N_Package_Specification
10539 Is_Compilation_Unit
10540 (Defining_Entity (Parent (Decl)))
10541 and then List_Containing (Parent (Parent (Decl))) =
10546 end Is_Private_Declaration;
10548 --------------------------
10549 -- Is_Overriding_Alias --
10550 --------------------------
10552 function Is_Overriding_Alias
10553 (Old_E : Entity_Id;
10554 New_E : Entity_Id) return Boolean
10556 AO : constant Entity_Id := Alias (Old_E);
10557 AN : constant Entity_Id := Alias (New_E);
10560 return Scope (AO) /= Scope (AN)
10561 or else No (DTC_Entity (AO))
10562 or else No (DTC_Entity (AN))
10563 or else DT_Position (AO) = DT_Position (AN);
10564 end Is_Overriding_Alias;
10566 ---------------------
10567 -- Report_Conflict --
10568 ---------------------
10570 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10572 Error_Msg_Sloc := Sloc (E);
10574 -- Generate message, with useful additional warning if in generic
10576 if Is_Generic_Unit (E) then
10577 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10578 Error_Msg_N ("\& conflicts with declaration#", S);
10580 Error_Msg_N ("& conflicts with declaration#", S);
10582 end Report_Conflict;
10584 -- Start of processing for New_Overloaded_Entity
10587 -- We need to look for an entity that S may override. This must be a
10588 -- homonym in the current scope, so we look for the first homonym of
10589 -- S in the current scope as the starting point for the search.
10591 E := Current_Entity_In_Scope (S);
10593 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10594 -- They are directly added to the list of primitive operations of
10595 -- Derived_Type, unless this is a rederivation in the private part
10596 -- of an operation that was already derived in the visible part of
10597 -- the current package.
10599 if Ada_Version >= Ada_2005
10600 and then Present (Derived_Type)
10601 and then Present (Alias (S))
10602 and then Is_Dispatching_Operation (Alias (S))
10603 and then Present (Find_Dispatching_Type (Alias (S)))
10604 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10606 -- For private types, when the full-view is processed we propagate to
10607 -- the full view the non-overridden entities whose attribute "alias"
10608 -- references an interface primitive. These entities were added by
10609 -- Derive_Subprograms to ensure that interface primitives are
10612 -- Inside_Freeze_Actions is non zero when S corresponds with an
10613 -- internal entity that links an interface primitive with its
10614 -- covering primitive through attribute Interface_Alias (see
10615 -- Add_Internal_Interface_Entities).
10617 if Inside_Freezing_Actions = 0
10618 and then Is_Package_Or_Generic_Package (Current_Scope)
10619 and then In_Private_Part (Current_Scope)
10620 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10621 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10622 and then Full_View (Defining_Identifier (Parent (E)))
10623 = Defining_Identifier (Parent (S))
10624 and then Alias (E) = Alias (S)
10626 Check_Operation_From_Private_View (S, E);
10627 Set_Is_Dispatching_Operation (S);
10632 Enter_Overloaded_Entity (S);
10633 Check_Dispatching_Operation (S, Empty);
10634 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10640 -- For synchronized types check conflicts of this entity with previously
10641 -- defined entities.
10643 if Ada_Version >= Ada_2005
10644 and then Has_Matching_Entry_Or_Subprogram (S)
10649 -- If there is no homonym then this is definitely not overriding
10652 Enter_Overloaded_Entity (S);
10653 Check_Dispatching_Operation (S, Empty);
10654 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10656 -- If subprogram has an explicit declaration, check whether it has an
10657 -- overriding indicator.
10659 if Comes_From_Source (S) then
10660 Check_Synchronized_Overriding (S, Overridden_Subp);
10662 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10663 -- it may have overridden some hidden inherited primitive. Update
10664 -- Overridden_Subp to avoid spurious errors when checking the
10665 -- overriding indicator.
10667 if Ada_Version >= Ada_2012
10668 and then No (Overridden_Subp)
10669 and then Is_Dispatching_Operation (S)
10670 and then Present (Overridden_Operation (S))
10672 Overridden_Subp := Overridden_Operation (S);
10675 Check_Overriding_Indicator
10676 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10678 -- The Ghost policy in effect at the point of declaration of a
10679 -- parent subprogram and an overriding subprogram must match
10680 -- (SPARK RM 6.9(17)).
10682 Check_Ghost_Overriding (S, Overridden_Subp);
10685 -- If there is a homonym that is not overloadable, then we have an
10686 -- error, except for the special cases checked explicitly below.
10688 elsif not Is_Overloadable (E) then
10690 -- Check for spurious conflict produced by a subprogram that has the
10691 -- same name as that of the enclosing generic package. The conflict
10692 -- occurs within an instance, between the subprogram and the renaming
10693 -- declaration for the package. After the subprogram, the package
10694 -- renaming declaration becomes hidden.
10696 if Ekind (E) = E_Package
10697 and then Present (Renamed_Object (E))
10698 and then Renamed_Object (E) = Current_Scope
10699 and then Nkind (Parent (Renamed_Object (E))) =
10700 N_Package_Specification
10701 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10704 Set_Is_Immediately_Visible (E, False);
10705 Enter_Overloaded_Entity (S);
10706 Set_Homonym (S, Homonym (E));
10707 Check_Dispatching_Operation (S, Empty);
10708 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10710 -- If the subprogram is implicit it is hidden by the previous
10711 -- declaration. However if it is dispatching, it must appear in the
10712 -- dispatch table anyway, because it can be dispatched to even if it
10713 -- cannot be called directly.
10715 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10716 Set_Scope (S, Current_Scope);
10718 if Is_Dispatching_Operation (Alias (S)) then
10719 Check_Dispatching_Operation (S, Empty);
10725 Report_Conflict (S, E);
10729 -- E exists and is overloadable
10732 Check_Synchronized_Overriding (S, Overridden_Subp);
10734 -- Loop through E and its homonyms to determine if any of them is
10735 -- the candidate for overriding by S.
10737 while Present (E) loop
10739 -- Definitely not interesting if not in the current scope
10741 if Scope (E) /= Current_Scope then
10744 -- A function can overload the name of an abstract state. The
10745 -- state can be viewed as a function with a profile that cannot
10746 -- be matched by anything.
10748 elsif Ekind (S) = E_Function
10749 and then Ekind (E) = E_Abstract_State
10751 Enter_Overloaded_Entity (S);
10754 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10755 -- procedures locate the internally generated spec. We enforce
10756 -- mode conformance since a tagged type may inherit from
10757 -- interfaces several null primitives which differ only in
10758 -- the mode of the formals.
10760 elsif not Comes_From_Source (S)
10761 and then Is_Null_Procedure (S)
10762 and then not Mode_Conformant (E, S)
10766 -- Check if we have type conformance
10768 elsif Type_Conformant (E, S) then
10770 -- If the old and new entities have the same profile and one
10771 -- is not the body of the other, then this is an error, unless
10772 -- one of them is implicitly declared.
10774 -- There are some cases when both can be implicit, for example
10775 -- when both a literal and a function that overrides it are
10776 -- inherited in a derivation, or when an inherited operation
10777 -- of a tagged full type overrides the inherited operation of
10778 -- a private extension. Ada 83 had a special rule for the
10779 -- literal case. In Ada 95, the later implicit operation hides
10780 -- the former, and the literal is always the former. In the
10781 -- odd case where both are derived operations declared at the
10782 -- same point, both operations should be declared, and in that
10783 -- case we bypass the following test and proceed to the next
10784 -- part. This can only occur for certain obscure cases in
10785 -- instances, when an operation on a type derived from a formal
10786 -- private type does not override a homograph inherited from
10787 -- the actual. In subsequent derivations of such a type, the
10788 -- DT positions of these operations remain distinct, if they
10791 if Present (Alias (S))
10792 and then (No (Alias (E))
10793 or else Comes_From_Source (E)
10794 or else Is_Abstract_Subprogram (S)
10796 (Is_Dispatching_Operation (E)
10797 and then Is_Overriding_Alias (E, S)))
10798 and then Ekind (E) /= E_Enumeration_Literal
10800 -- When an derived operation is overloaded it may be due to
10801 -- the fact that the full view of a private extension
10802 -- re-inherits. It has to be dealt with.
10804 if Is_Package_Or_Generic_Package (Current_Scope)
10805 and then In_Private_Part (Current_Scope)
10807 Check_Operation_From_Private_View (S, E);
10810 -- In any case the implicit operation remains hidden by the
10811 -- existing declaration, which is overriding. Indicate that
10812 -- E overrides the operation from which S is inherited.
10814 if Present (Alias (S)) then
10815 Set_Overridden_Operation (E, Alias (S));
10816 Inherit_Subprogram_Contract (E, Alias (S));
10819 Set_Overridden_Operation (E, S);
10820 Inherit_Subprogram_Contract (E, S);
10823 if Comes_From_Source (E) then
10824 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10826 -- The Ghost policy in effect at the point of declaration
10827 -- of a parent subprogram and an overriding subprogram
10828 -- must match (SPARK RM 6.9(17)).
10830 Check_Ghost_Overriding (E, S);
10835 -- Within an instance, the renaming declarations for actual
10836 -- subprograms may become ambiguous, but they do not hide each
10839 elsif Ekind (E) /= E_Entry
10840 and then not Comes_From_Source (E)
10841 and then not Is_Generic_Instance (E)
10842 and then (Present (Alias (E))
10843 or else Is_Intrinsic_Subprogram (E))
10844 and then (not In_Instance
10845 or else No (Parent (E))
10846 or else Nkind (Unit_Declaration_Node (E)) /=
10847 N_Subprogram_Renaming_Declaration)
10849 -- A subprogram child unit is not allowed to override an
10850 -- inherited subprogram (10.1.1(20)).
10852 if Is_Child_Unit (S) then
10854 ("child unit overrides inherited subprogram in parent",
10859 if Is_Non_Overriding_Operation (E, S) then
10860 Enter_Overloaded_Entity (S);
10862 if No (Derived_Type)
10863 or else Is_Tagged_Type (Derived_Type)
10865 Check_Dispatching_Operation (S, Empty);
10871 -- E is a derived operation or an internal operator which
10872 -- is being overridden. Remove E from further visibility.
10873 -- Furthermore, if E is a dispatching operation, it must be
10874 -- replaced in the list of primitive operations of its type
10875 -- (see Override_Dispatching_Operation).
10877 Overridden_Subp := E;
10879 -- It is possible for E to be in the current scope and
10880 -- yet not in the entity chain. This can only occur in a
10881 -- generic context where E is an implicit concatenation
10882 -- in the formal part, because in a generic body the
10883 -- entity chain starts with the formals.
10885 -- In GNATprove mode, a wrapper for an operation with
10886 -- axiomatization may be a homonym of another declaration
10887 -- for an actual subprogram (needs refinement ???).
10889 if No (Prev_Entity (E)) then
10891 and then GNATprove_Mode
10893 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10894 N_Subprogram_Renaming_Declaration
10898 pragma Assert (Chars (E) = Name_Op_Concat);
10903 -- E must be removed both from the entity_list of the
10904 -- current scope, and from the visibility chain.
10906 if Debug_Flag_E then
10907 Write_Str ("Override implicit operation ");
10908 Write_Int (Int (E));
10912 -- If E is a predefined concatenation, it stands for four
10913 -- different operations. As a result, a single explicit
10914 -- declaration does not hide it. In a possible ambiguous
10915 -- situation, Disambiguate chooses the user-defined op,
10916 -- so it is correct to retain the previous internal one.
10918 if Chars (E) /= Name_Op_Concat
10919 or else Ekind (E) /= E_Operator
10921 -- For nondispatching derived operations that are
10922 -- overridden by a subprogram declared in the private
10923 -- part of a package, we retain the derived subprogram
10924 -- but mark it as not immediately visible. If the
10925 -- derived operation was declared in the visible part
10926 -- then this ensures that it will still be visible
10927 -- outside the package with the proper signature
10928 -- (calls from outside must also be directed to this
10929 -- version rather than the overriding one, unlike the
10930 -- dispatching case). Calls from inside the package
10931 -- will still resolve to the overriding subprogram
10932 -- since the derived one is marked as not visible
10933 -- within the package.
10935 -- If the private operation is dispatching, we achieve
10936 -- the overriding by keeping the implicit operation
10937 -- but setting its alias to be the overriding one. In
10938 -- this fashion the proper body is executed in all
10939 -- cases, but the original signature is used outside
10942 -- If the overriding is not in the private part, we
10943 -- remove the implicit operation altogether.
10945 if Is_Private_Declaration (S) then
10946 if not Is_Dispatching_Operation (E) then
10947 Set_Is_Immediately_Visible (E, False);
10949 -- Work done in Override_Dispatching_Operation, so
10950 -- nothing else needs to be done here.
10956 Remove_Entity_And_Homonym (E);
10960 Enter_Overloaded_Entity (S);
10962 -- For entities generated by Derive_Subprograms the
10963 -- overridden operation is the inherited primitive
10964 -- (which is available through the attribute alias).
10966 if not (Comes_From_Source (E))
10967 and then Is_Dispatching_Operation (E)
10968 and then Find_Dispatching_Type (E) =
10969 Find_Dispatching_Type (S)
10970 and then Present (Alias (E))
10971 and then Comes_From_Source (Alias (E))
10973 Set_Overridden_Operation (S, Alias (E));
10974 Inherit_Subprogram_Contract (S, Alias (E));
10976 -- Normal case of setting entity as overridden
10978 -- Note: Static_Initialization and Overridden_Operation
10979 -- attributes use the same field in subprogram entities.
10980 -- Static_Initialization is only defined for internal
10981 -- initialization procedures, where Overridden_Operation
10982 -- is irrelevant. Therefore the setting of this attribute
10983 -- must check whether the target is an init_proc.
10985 elsif not Is_Init_Proc (S) then
10986 Set_Overridden_Operation (S, E);
10987 Inherit_Subprogram_Contract (S, E);
10990 Check_Overriding_Indicator (S, E, Is_Primitive => True);
10992 -- The Ghost policy in effect at the point of declaration
10993 -- of a parent subprogram and an overriding subprogram
10994 -- must match (SPARK RM 6.9(17)).
10996 Check_Ghost_Overriding (S, E);
10998 -- If S is a user-defined subprogram or a null procedure
10999 -- expanded to override an inherited null procedure, or a
11000 -- predefined dispatching primitive then indicate that E
11001 -- overrides the operation from which S is inherited.
11003 if Comes_From_Source (S)
11005 (Present (Parent (S))
11006 and then Nkind (Parent (S)) = N_Procedure_Specification
11007 and then Null_Present (Parent (S)))
11009 (Present (Alias (E))
11011 Is_Predefined_Dispatching_Operation (Alias (E)))
11013 if Present (Alias (E)) then
11014 Set_Overridden_Operation (S, Alias (E));
11015 Inherit_Subprogram_Contract (S, Alias (E));
11019 if Is_Dispatching_Operation (E) then
11021 -- An overriding dispatching subprogram inherits the
11022 -- convention of the overridden subprogram (AI-117).
11024 Set_Convention (S, Convention (E));
11025 Check_Dispatching_Operation (S, E);
11028 Check_Dispatching_Operation (S, Empty);
11031 Check_For_Primitive_Subprogram
11032 (Is_Primitive_Subp, Is_Overriding => True);
11033 goto Check_Inequality;
11035 -- Apparent redeclarations in instances can occur when two
11036 -- formal types get the same actual type. The subprograms in
11037 -- in the instance are legal, even if not callable from the
11038 -- outside. Calls from within are disambiguated elsewhere.
11039 -- For dispatching operations in the visible part, the usual
11040 -- rules apply, and operations with the same profile are not
11041 -- legal (B830001).
11043 elsif (In_Instance_Visible_Part
11044 and then not Is_Dispatching_Operation (E))
11045 or else In_Instance_Not_Visible
11049 -- Here we have a real error (identical profile)
11052 Error_Msg_Sloc := Sloc (E);
11054 -- Avoid cascaded errors if the entity appears in
11055 -- subsequent calls.
11057 Set_Scope (S, Current_Scope);
11059 -- Generate error, with extra useful warning for the case
11060 -- of a generic instance with no completion.
11062 if Is_Generic_Instance (S)
11063 and then not Has_Completion (E)
11066 ("instantiation cannot provide body for&", S);
11067 Error_Msg_N ("\& conflicts with declaration#", S);
11069 Error_Msg_N ("& conflicts with declaration#", S);
11076 -- If one subprogram has an access parameter and the other
11077 -- a parameter of an access type, calls to either might be
11078 -- ambiguous. Verify that parameters match except for the
11079 -- access parameter.
11081 if May_Hide_Profile then
11087 F1 := First_Formal (S);
11088 F2 := First_Formal (E);
11089 while Present (F1) and then Present (F2) loop
11090 if Is_Access_Type (Etype (F1)) then
11091 if not Is_Access_Type (Etype (F2))
11092 or else not Conforming_Types
11093 (Designated_Type (Etype (F1)),
11094 Designated_Type (Etype (F2)),
11097 May_Hide_Profile := False;
11101 not Conforming_Types
11102 (Etype (F1), Etype (F2), Type_Conformant)
11104 May_Hide_Profile := False;
11111 if May_Hide_Profile
11115 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11124 -- On exit, we know that S is a new entity
11126 Enter_Overloaded_Entity (S);
11127 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11128 Check_Overriding_Indicator
11129 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11131 -- The Ghost policy in effect at the point of declaration of a parent
11132 -- subprogram and an overriding subprogram must match
11133 -- (SPARK RM 6.9(17)).
11135 Check_Ghost_Overriding (S, Overridden_Subp);
11137 -- Overloading is not allowed in SPARK, except for operators
11139 if Nkind (S) /= N_Defining_Operator_Symbol then
11140 Error_Msg_Sloc := Sloc (Homonym (S));
11141 Check_SPARK_05_Restriction
11142 ("overloading not allowed with entity#", S);
11145 -- If S is a derived operation for an untagged type then by
11146 -- definition it's not a dispatching operation (even if the parent
11147 -- operation was dispatching), so Check_Dispatching_Operation is not
11148 -- called in that case.
11150 if No (Derived_Type)
11151 or else Is_Tagged_Type (Derived_Type)
11153 Check_Dispatching_Operation (S, Empty);
11157 -- If this is a user-defined equality operator that is not a derived
11158 -- subprogram, create the corresponding inequality. If the operation is
11159 -- dispatching, the expansion is done elsewhere, and we do not create
11160 -- an explicit inequality operation.
11162 <<Check_Inequality>>
11163 if Chars (S) = Name_Op_Eq
11164 and then Etype (S) = Standard_Boolean
11165 and then Present (Parent (S))
11166 and then not Is_Dispatching_Operation (S)
11168 Make_Inequality_Operator (S);
11169 Check_Untagged_Equality (S);
11171 end New_Overloaded_Entity;
11173 ----------------------------------
11174 -- Preanalyze_Formal_Expression --
11175 ----------------------------------
11177 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id) is
11178 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
11180 In_Spec_Expression := True;
11181 Preanalyze_With_Freezing_And_Resolve (N, T);
11182 In_Spec_Expression := Save_In_Spec_Expression;
11183 end Preanalyze_Formal_Expression;
11185 ---------------------
11186 -- Process_Formals --
11187 ---------------------
11189 procedure Process_Formals
11191 Related_Nod : Node_Id)
11193 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11194 -- Determine whether an access type designates a type coming from a
11197 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11198 -- Check whether the default has a class-wide type. After analysis the
11199 -- default has the type of the formal, so we must also check explicitly
11200 -- for an access attribute.
11202 ----------------------------------
11203 -- Designates_From_Limited_With --
11204 ----------------------------------
11206 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11207 Desig : Entity_Id := Typ;
11210 if Is_Access_Type (Desig) then
11211 Desig := Directly_Designated_Type (Desig);
11214 if Is_Class_Wide_Type (Desig) then
11215 Desig := Root_Type (Desig);
11219 Ekind (Desig) = E_Incomplete_Type
11220 and then From_Limited_With (Desig);
11221 end Designates_From_Limited_With;
11223 ---------------------------
11224 -- Is_Class_Wide_Default --
11225 ---------------------------
11227 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11229 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11230 or else (Nkind (D) = N_Attribute_Reference
11231 and then Attribute_Name (D) = Name_Access
11232 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11233 end Is_Class_Wide_Default;
11237 Context : constant Node_Id := Parent (Parent (T));
11239 Formal : Entity_Id;
11240 Formal_Type : Entity_Id;
11241 Param_Spec : Node_Id;
11244 Num_Out_Params : Nat := 0;
11245 First_Out_Param : Entity_Id := Empty;
11246 -- Used for setting Is_Only_Out_Parameter
11248 -- Start of processing for Process_Formals
11251 -- In order to prevent premature use of the formals in the same formal
11252 -- part, the Ekind is left undefined until all default expressions are
11253 -- analyzed. The Ekind is established in a separate loop at the end.
11255 Param_Spec := First (T);
11256 while Present (Param_Spec) loop
11257 Formal := Defining_Identifier (Param_Spec);
11258 Set_Never_Set_In_Source (Formal, True);
11259 Enter_Name (Formal);
11261 -- Case of ordinary parameters
11263 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11264 Find_Type (Parameter_Type (Param_Spec));
11265 Ptype := Parameter_Type (Param_Spec);
11267 if Ptype = Error then
11271 Formal_Type := Entity (Ptype);
11273 if Is_Incomplete_Type (Formal_Type)
11275 (Is_Class_Wide_Type (Formal_Type)
11276 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11278 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11279 -- primitive operations, as long as their completion is
11280 -- in the same declarative part. If in the private part
11281 -- this means that the type cannot be a Taft-amendment type.
11282 -- Check is done on package exit. For access to subprograms,
11283 -- the use is legal for Taft-amendment types.
11285 -- Ada 2012: tagged incomplete types are allowed as generic
11286 -- formal types. They do not introduce dependencies and the
11287 -- corresponding generic subprogram does not have a delayed
11288 -- freeze, because it does not need a freeze node. However,
11289 -- it is still the case that untagged incomplete types cannot
11290 -- be Taft-amendment types and must be completed in private
11291 -- part, so the subprogram must appear in the list of private
11292 -- dependents of the type.
11294 if Is_Tagged_Type (Formal_Type)
11295 or else (Ada_Version >= Ada_2012
11296 and then not From_Limited_With (Formal_Type)
11297 and then not Is_Generic_Type (Formal_Type))
11299 if Ekind (Scope (Current_Scope)) = E_Package
11300 and then not Is_Generic_Type (Formal_Type)
11301 and then not Is_Class_Wide_Type (Formal_Type)
11304 (Parent (T), N_Access_Function_Definition,
11305 N_Access_Procedure_Definition)
11307 Append_Elmt (Current_Scope,
11308 Private_Dependents (Base_Type (Formal_Type)));
11310 -- Freezing is delayed to ensure that Register_Prim
11311 -- will get called for this operation, which is needed
11312 -- in cases where static dispatch tables aren't built.
11313 -- (Note that the same is done for controlling access
11314 -- parameter cases in function Access_Definition.)
11316 if not Is_Thunk (Current_Scope) then
11317 Set_Has_Delayed_Freeze (Current_Scope);
11322 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11323 N_Access_Procedure_Definition)
11325 -- AI05-0151: Tagged incomplete types are allowed in all
11326 -- formal parts. Untagged incomplete types are not allowed
11327 -- in bodies. Limited views of either kind are not allowed
11328 -- if there is no place at which the non-limited view can
11329 -- become available.
11331 -- Incomplete formal untagged types are not allowed in
11332 -- subprogram bodies (but are legal in their declarations).
11333 -- This excludes bodies created for null procedures, which
11334 -- are basic declarations.
11336 if Is_Generic_Type (Formal_Type)
11337 and then not Is_Tagged_Type (Formal_Type)
11338 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11341 ("invalid use of formal incomplete type", Param_Spec);
11343 elsif Ada_Version >= Ada_2012 then
11344 if Is_Tagged_Type (Formal_Type)
11345 and then (not From_Limited_With (Formal_Type)
11346 or else not In_Package_Body)
11350 elsif Nkind_In (Context, N_Accept_Statement,
11351 N_Accept_Alternative,
11353 or else (Nkind (Context) = N_Subprogram_Body
11354 and then Comes_From_Source (Context))
11357 ("invalid use of untagged incomplete type &",
11358 Ptype, Formal_Type);
11363 ("invalid use of incomplete type&",
11364 Param_Spec, Formal_Type);
11366 -- Further checks on the legality of incomplete types
11367 -- in formal parts are delayed until the freeze point
11368 -- of the enclosing subprogram or access to subprogram.
11372 elsif Ekind (Formal_Type) = E_Void then
11374 ("premature use of&",
11375 Parameter_Type (Param_Spec), Formal_Type);
11378 -- Ada 2012 (AI-142): Handle aliased parameters
11380 if Ada_Version >= Ada_2012
11381 and then Aliased_Present (Param_Spec)
11383 Set_Is_Aliased (Formal);
11386 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11387 -- declaration corresponding to the null-excluding type of the
11388 -- formal in the enclosing scope. Finally, replace the parameter
11389 -- type of the formal with the internal subtype.
11391 if Ada_Version >= Ada_2005
11392 and then Null_Exclusion_Present (Param_Spec)
11394 if not Is_Access_Type (Formal_Type) then
11396 ("`NOT NULL` allowed only for an access type", Param_Spec);
11399 if Can_Never_Be_Null (Formal_Type)
11400 and then Comes_From_Source (Related_Nod)
11403 ("`NOT NULL` not allowed (& already excludes null)",
11404 Param_Spec, Formal_Type);
11408 Create_Null_Excluding_Itype
11410 Related_Nod => Related_Nod,
11411 Scope_Id => Scope (Current_Scope));
11413 -- If the designated type of the itype is an itype that is
11414 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11415 -- on the access subtype, to prevent order-of-elaboration
11416 -- issues in the backend.
11419 -- type T is access procedure;
11420 -- procedure Op (O : not null T);
11422 if Is_Itype (Directly_Designated_Type (Formal_Type))
11424 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11426 Set_Has_Delayed_Freeze (Formal_Type);
11431 -- An access formal type
11435 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11437 -- No need to continue if we already notified errors
11439 if not Present (Formal_Type) then
11443 -- Ada 2005 (AI-254)
11446 AD : constant Node_Id :=
11447 Access_To_Subprogram_Definition
11448 (Parameter_Type (Param_Spec));
11450 if Present (AD) and then Protected_Present (AD) then
11452 Replace_Anonymous_Access_To_Protected_Subprogram
11458 Set_Etype (Formal, Formal_Type);
11460 -- Deal with default expression if present
11462 Default := Expression (Param_Spec);
11464 if Present (Default) then
11465 Check_SPARK_05_Restriction
11466 ("default expression is not allowed", Default);
11468 if Out_Present (Param_Spec) then
11470 ("default initialization only allowed for IN parameters",
11474 -- Do the special preanalysis of the expression (see section on
11475 -- "Handling of Default Expressions" in the spec of package Sem).
11477 Preanalyze_Formal_Expression (Default, Formal_Type);
11479 -- An access to constant cannot be the default for
11480 -- an access parameter that is an access to variable.
11482 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11483 and then not Is_Access_Constant (Formal_Type)
11484 and then Is_Access_Type (Etype (Default))
11485 and then Is_Access_Constant (Etype (Default))
11488 ("formal that is access to variable cannot be initialized "
11489 & "with an access-to-constant expression", Default);
11492 -- Check that the designated type of an access parameter's default
11493 -- is not a class-wide type unless the parameter's designated type
11494 -- is also class-wide.
11496 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11497 and then not Designates_From_Limited_With (Formal_Type)
11498 and then Is_Class_Wide_Default (Default)
11499 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11502 ("access to class-wide expression not allowed here", Default);
11505 -- Check incorrect use of dynamically tagged expressions
11507 if Is_Tagged_Type (Formal_Type) then
11508 Check_Dynamically_Tagged_Expression
11510 Typ => Formal_Type,
11511 Related_Nod => Default);
11515 -- Ada 2005 (AI-231): Static checks
11517 if Ada_Version >= Ada_2005
11518 and then Is_Access_Type (Etype (Formal))
11519 and then Can_Never_Be_Null (Etype (Formal))
11521 Null_Exclusion_Static_Checks (Param_Spec);
11524 -- The following checks are relevant only when SPARK_Mode is on as
11525 -- these are not standard Ada legality rules.
11527 if SPARK_Mode = On then
11528 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11530 -- A function cannot have a parameter of mode IN OUT or OUT
11533 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11535 ("function cannot have parameter of mode `OUT` or "
11536 & "`IN OUT`", Formal);
11539 -- A procedure cannot have an effectively volatile formal
11540 -- parameter of mode IN because it behaves as a constant
11541 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11543 elsif Ekind (Scope (Formal)) = E_Procedure
11544 and then Ekind (Formal) = E_In_Parameter
11545 and then Is_Effectively_Volatile (Formal)
11548 ("formal parameter of mode `IN` cannot be volatile", Formal);
11556 -- If this is the formal part of a function specification, analyze the
11557 -- subtype mark in the context where the formals are visible but not
11558 -- yet usable, and may hide outer homographs.
11560 if Nkind (Related_Nod) = N_Function_Specification then
11561 Analyze_Return_Type (Related_Nod);
11564 -- Now set the kind (mode) of each formal
11566 Param_Spec := First (T);
11567 while Present (Param_Spec) loop
11568 Formal := Defining_Identifier (Param_Spec);
11569 Set_Formal_Mode (Formal);
11571 if Ekind (Formal) = E_In_Parameter then
11572 Set_Default_Value (Formal, Expression (Param_Spec));
11574 if Present (Expression (Param_Spec)) then
11575 Default := Expression (Param_Spec);
11577 if Is_Scalar_Type (Etype (Default)) then
11578 if Nkind (Parameter_Type (Param_Spec)) /=
11579 N_Access_Definition
11581 Formal_Type := Entity (Parameter_Type (Param_Spec));
11585 (Related_Nod, Parameter_Type (Param_Spec));
11588 Apply_Scalar_Range_Check (Default, Formal_Type);
11592 elsif Ekind (Formal) = E_Out_Parameter then
11593 Num_Out_Params := Num_Out_Params + 1;
11595 if Num_Out_Params = 1 then
11596 First_Out_Param := Formal;
11599 elsif Ekind (Formal) = E_In_Out_Parameter then
11600 Num_Out_Params := Num_Out_Params + 1;
11603 -- Skip remaining processing if formal type was in error
11605 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11606 goto Next_Parameter;
11609 -- Force call by reference if aliased
11612 Conv : constant Convention_Id := Convention (Etype (Formal));
11614 if Is_Aliased (Formal) then
11615 Set_Mechanism (Formal, By_Reference);
11617 -- Warn if user asked this to be passed by copy
11619 if Conv = Convention_Ada_Pass_By_Copy then
11621 ("cannot pass aliased parameter & by copy??", Formal);
11624 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11626 elsif Conv = Convention_Ada_Pass_By_Copy then
11627 Set_Mechanism (Formal, By_Copy);
11629 elsif Conv = Convention_Ada_Pass_By_Reference then
11630 Set_Mechanism (Formal, By_Reference);
11638 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11639 Set_Is_Only_Out_Parameter (First_Out_Param);
11641 end Process_Formals;
11643 ----------------------------
11644 -- Reference_Body_Formals --
11645 ----------------------------
11647 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11652 if Error_Posted (Spec) then
11656 -- Iterate over both lists. They may be of different lengths if the two
11657 -- specs are not conformant.
11659 Fs := First_Formal (Spec);
11660 Fb := First_Formal (Bod);
11661 while Present (Fs) and then Present (Fb) loop
11662 Generate_Reference (Fs, Fb, 'b');
11664 if Style_Check then
11665 Style.Check_Identifier (Fb, Fs);
11668 Set_Spec_Entity (Fb, Fs);
11669 Set_Referenced (Fs, False);
11673 end Reference_Body_Formals;
11675 -------------------------
11676 -- Set_Actual_Subtypes --
11677 -------------------------
11679 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11681 Formal : Entity_Id;
11683 First_Stmt : Node_Id := Empty;
11684 AS_Needed : Boolean;
11687 -- If this is an empty initialization procedure, no need to create
11688 -- actual subtypes (small optimization).
11690 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11693 -- Within a predicate function we do not want to generate local
11694 -- subtypes that may generate nested predicate functions.
11696 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11700 -- The subtype declarations may freeze the formals. The body generated
11701 -- for an expression function is not a freeze point, so do not emit
11702 -- these declarations (small loss of efficiency in rare cases).
11704 if Nkind (N) = N_Subprogram_Body
11705 and then Was_Expression_Function (N)
11710 Formal := First_Formal (Subp);
11711 while Present (Formal) loop
11712 T := Etype (Formal);
11714 -- We never need an actual subtype for a constrained formal
11716 if Is_Constrained (T) then
11717 AS_Needed := False;
11719 -- If we have unknown discriminants, then we do not need an actual
11720 -- subtype, or more accurately we cannot figure it out. Note that
11721 -- all class-wide types have unknown discriminants.
11723 elsif Has_Unknown_Discriminants (T) then
11724 AS_Needed := False;
11726 -- At this stage we have an unconstrained type that may need an
11727 -- actual subtype. For sure the actual subtype is needed if we have
11728 -- an unconstrained array type. However, in an instance, the type
11729 -- may appear as a subtype of the full view, while the actual is
11730 -- in fact private (in which case no actual subtype is needed) so
11731 -- check the kind of the base type.
11733 elsif Is_Array_Type (Base_Type (T)) then
11736 -- The only other case needing an actual subtype is an unconstrained
11737 -- record type which is an IN parameter (we cannot generate actual
11738 -- subtypes for the OUT or IN OUT case, since an assignment can
11739 -- change the discriminant values. However we exclude the case of
11740 -- initialization procedures, since discriminants are handled very
11741 -- specially in this context, see the section entitled "Handling of
11742 -- Discriminants" in Einfo.
11744 -- We also exclude the case of Discrim_SO_Functions (functions used
11745 -- in front-end layout mode for size/offset values), since in such
11746 -- functions only discriminants are referenced, and not only are such
11747 -- subtypes not needed, but they cannot always be generated, because
11748 -- of order of elaboration issues.
11750 elsif Is_Record_Type (T)
11751 and then Ekind (Formal) = E_In_Parameter
11752 and then Chars (Formal) /= Name_uInit
11753 and then not Is_Unchecked_Union (T)
11754 and then not Is_Discrim_SO_Function (Subp)
11758 -- All other cases do not need an actual subtype
11761 AS_Needed := False;
11764 -- Generate actual subtypes for unconstrained arrays and
11765 -- unconstrained discriminated records.
11768 if Nkind (N) = N_Accept_Statement then
11770 -- If expansion is active, the formal is replaced by a local
11771 -- variable that renames the corresponding entry of the
11772 -- parameter block, and it is this local variable that may
11773 -- require an actual subtype.
11775 if Expander_Active then
11776 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11778 Decl := Build_Actual_Subtype (T, Formal);
11781 if Present (Handled_Statement_Sequence (N)) then
11783 First (Statements (Handled_Statement_Sequence (N)));
11784 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11785 Mark_Rewrite_Insertion (Decl);
11787 -- If the accept statement has no body, there will be no
11788 -- reference to the actuals, so no need to compute actual
11795 Decl := Build_Actual_Subtype (T, Formal);
11796 Prepend (Decl, Declarations (N));
11797 Mark_Rewrite_Insertion (Decl);
11800 -- The declaration uses the bounds of an existing object, and
11801 -- therefore needs no constraint checks.
11803 Analyze (Decl, Suppress => All_Checks);
11804 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11806 -- We need to freeze manually the generated type when it is
11807 -- inserted anywhere else than in a declarative part.
11809 if Present (First_Stmt) then
11810 Insert_List_Before_And_Analyze (First_Stmt,
11811 Freeze_Entity (Defining_Identifier (Decl), N));
11813 -- Ditto if the type has a dynamic predicate, because the
11814 -- generated function will mention the actual subtype. The
11815 -- predicate may come from an explicit aspect of be inherited.
11817 elsif Has_Predicates (T) then
11818 Insert_List_Before_And_Analyze (Decl,
11819 Freeze_Entity (Defining_Identifier (Decl), N));
11822 if Nkind (N) = N_Accept_Statement
11823 and then Expander_Active
11825 Set_Actual_Subtype (Renamed_Object (Formal),
11826 Defining_Identifier (Decl));
11828 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11832 Next_Formal (Formal);
11834 end Set_Actual_Subtypes;
11836 ---------------------
11837 -- Set_Formal_Mode --
11838 ---------------------
11840 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11841 Spec : constant Node_Id := Parent (Formal_Id);
11842 Id : constant Entity_Id := Scope (Formal_Id);
11845 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11846 -- since we ensure that corresponding actuals are always valid at the
11847 -- point of the call.
11849 if Out_Present (Spec) then
11850 if Ekind_In (Id, E_Entry, E_Entry_Family)
11851 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11853 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11856 if Ekind_In (Id, E_Function, E_Generic_Function) then
11858 -- [IN] OUT parameters allowed for functions in Ada 2012
11860 if Ada_Version >= Ada_2012 then
11862 -- Even in Ada 2012 operators can only have IN parameters
11864 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11865 Error_Msg_N ("operators can only have IN parameters", Spec);
11868 if In_Present (Spec) then
11869 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11871 Set_Ekind (Formal_Id, E_Out_Parameter);
11874 -- But not in earlier versions of Ada
11877 Error_Msg_N ("functions can only have IN parameters", Spec);
11878 Set_Ekind (Formal_Id, E_In_Parameter);
11881 elsif In_Present (Spec) then
11882 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11885 Set_Ekind (Formal_Id, E_Out_Parameter);
11886 Set_Never_Set_In_Source (Formal_Id, True);
11887 Set_Is_True_Constant (Formal_Id, False);
11888 Set_Current_Value (Formal_Id, Empty);
11892 Set_Ekind (Formal_Id, E_In_Parameter);
11895 -- Set Is_Known_Non_Null for access parameters since the language
11896 -- guarantees that access parameters are always non-null. We also set
11897 -- Can_Never_Be_Null, since there is no way to change the value.
11899 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11901 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11902 -- null; In Ada 2005, only if then null_exclusion is explicit.
11904 if Ada_Version < Ada_2005
11905 or else Can_Never_Be_Null (Etype (Formal_Id))
11907 Set_Is_Known_Non_Null (Formal_Id);
11908 Set_Can_Never_Be_Null (Formal_Id);
11911 -- Ada 2005 (AI-231): Null-exclusion access subtype
11913 elsif Is_Access_Type (Etype (Formal_Id))
11914 and then Can_Never_Be_Null (Etype (Formal_Id))
11916 Set_Is_Known_Non_Null (Formal_Id);
11918 -- We can also set Can_Never_Be_Null (thus preventing some junk
11919 -- access checks) for the case of an IN parameter, which cannot
11920 -- be changed, or for an IN OUT parameter, which can be changed but
11921 -- not to a null value. But for an OUT parameter, the initial value
11922 -- passed in can be null, so we can't set this flag in that case.
11924 if Ekind (Formal_Id) /= E_Out_Parameter then
11925 Set_Can_Never_Be_Null (Formal_Id);
11929 Set_Mechanism (Formal_Id, Default_Mechanism);
11930 Set_Formal_Validity (Formal_Id);
11931 end Set_Formal_Mode;
11933 -------------------------
11934 -- Set_Formal_Validity --
11935 -------------------------
11937 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11939 -- If no validity checking, then we cannot assume anything about the
11940 -- validity of parameters, since we do not know there is any checking
11941 -- of the validity on the call side.
11943 if not Validity_Checks_On then
11946 -- If validity checking for parameters is enabled, this means we are
11947 -- not supposed to make any assumptions about argument values.
11949 elsif Validity_Check_Parameters then
11952 -- If we are checking in parameters, we will assume that the caller is
11953 -- also checking parameters, so we can assume the parameter is valid.
11955 elsif Ekind (Formal_Id) = E_In_Parameter
11956 and then Validity_Check_In_Params
11958 Set_Is_Known_Valid (Formal_Id, True);
11960 -- Similar treatment for IN OUT parameters
11962 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11963 and then Validity_Check_In_Out_Params
11965 Set_Is_Known_Valid (Formal_Id, True);
11967 end Set_Formal_Validity;
11969 ------------------------
11970 -- Subtype_Conformant --
11971 ------------------------
11973 function Subtype_Conformant
11974 (New_Id : Entity_Id;
11975 Old_Id : Entity_Id;
11976 Skip_Controlling_Formals : Boolean := False) return Boolean
11980 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
11981 Skip_Controlling_Formals => Skip_Controlling_Formals);
11983 end Subtype_Conformant;
11985 ---------------------
11986 -- Type_Conformant --
11987 ---------------------
11989 function Type_Conformant
11990 (New_Id : Entity_Id;
11991 Old_Id : Entity_Id;
11992 Skip_Controlling_Formals : Boolean := False) return Boolean
11996 May_Hide_Profile := False;
11998 (New_Id, Old_Id, Type_Conformant, False, Result,
11999 Skip_Controlling_Formals => Skip_Controlling_Formals);
12001 end Type_Conformant;
12003 -------------------------------
12004 -- Valid_Operator_Definition --
12005 -------------------------------
12007 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12010 Id : constant Name_Id := Chars (Designator);
12014 F := First_Formal (Designator);
12015 while Present (F) loop
12018 if Present (Default_Value (F)) then
12020 ("default values not allowed for operator parameters",
12023 -- For function instantiations that are operators, we must check
12024 -- separately that the corresponding generic only has in-parameters.
12025 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12026 -- an error could not arise in earlier versions of the language.
12028 elsif Ekind (F) /= E_In_Parameter then
12029 Error_Msg_N ("operators can only have IN parameters", F);
12035 -- Verify that user-defined operators have proper number of arguments
12036 -- First case of operators which can only be unary
12038 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12041 -- Case of operators which can be unary or binary
12043 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12044 N_OK := (N in 1 .. 2);
12046 -- All other operators can only be binary
12054 ("incorrect number of arguments for operator", Designator);
12058 and then Base_Type (Etype (Designator)) = Standard_Boolean
12059 and then not Is_Intrinsic_Subprogram (Designator)
12062 ("explicit definition of inequality not allowed", Designator);
12064 end Valid_Operator_Definition;