1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2019, 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 -- WARNING: This routine manages Ghost regions. Return statements must be
1400 -- replaced by gotos that jump to the end of the routine and restore the
1403 procedure Analyze_Null_Procedure
1405 Is_Completion : out Boolean)
1407 Loc : constant Source_Ptr := Sloc (N);
1408 Spec : constant Node_Id := Specification (N);
1410 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1411 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1412 Saved_ISMP : constant Boolean :=
1413 Ignore_SPARK_Mode_Pragmas_In_Instance;
1414 -- Save the Ghost and SPARK mode-related data to restore on exit
1416 Designator : Entity_Id;
1418 Null_Body : Node_Id := Empty;
1419 Null_Stmt : Node_Id := Null_Statement (Spec);
1423 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1425 -- A null procedure is Ghost when it is stand-alone and is subject to
1426 -- pragma Ghost, or when the corresponding spec is Ghost. Set the mode
1427 -- now, to ensure that any nodes generated during analysis and expansion
1428 -- are properly marked as Ghost.
1430 if Present (Prev) then
1431 Mark_And_Set_Ghost_Body (N, Prev);
1434 -- Capture the profile of the null procedure before analysis, for
1435 -- expansion at the freeze point and at each point of call. The body is
1436 -- used if the procedure has preconditions, or if it is a completion. In
1437 -- the first case the body is analyzed at the freeze point, in the other
1438 -- it replaces the null procedure declaration.
1440 -- For a null procedure that comes from source, a NULL statement is
1441 -- provided by the parser, which carries the source location of the
1442 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1443 -- from expansion, create one now.
1445 if No (Null_Stmt) then
1446 Null_Stmt := Make_Null_Statement (Loc);
1450 Make_Subprogram_Body (Loc,
1451 Specification => New_Copy_Tree (Spec),
1452 Declarations => New_List,
1453 Handled_Statement_Sequence =>
1454 Make_Handled_Sequence_Of_Statements (Loc,
1455 Statements => New_List (Null_Stmt)));
1457 -- Create new entities for body and formals
1459 Set_Defining_Unit_Name (Specification (Null_Body),
1460 Make_Defining_Identifier
1461 (Sloc (Defining_Entity (N)),
1462 Chars (Defining_Entity (N))));
1464 Form := First (Parameter_Specifications (Specification (Null_Body)));
1465 while Present (Form) loop
1466 Set_Defining_Identifier (Form,
1467 Make_Defining_Identifier
1468 (Sloc (Defining_Identifier (Form)),
1469 Chars (Defining_Identifier (Form))));
1473 -- Determine whether the null procedure may be a completion of a generic
1474 -- suprogram, in which case we use the new null body as the completion
1475 -- and set minimal semantic information on the original declaration,
1476 -- which is rewritten as a null statement.
1478 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1479 Insert_Before (N, Null_Body);
1480 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1482 Rewrite (N, Make_Null_Statement (Loc));
1483 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1484 Is_Completion := True;
1489 -- Resolve the types of the formals now, because the freeze point may
1490 -- appear in a different context, e.g. an instantiation.
1492 Form := First (Parameter_Specifications (Specification (Null_Body)));
1493 while Present (Form) loop
1494 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1495 Find_Type (Parameter_Type (Form));
1497 elsif No (Access_To_Subprogram_Definition
1498 (Parameter_Type (Form)))
1500 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1502 -- The case of a null procedure with a formal that is an
1503 -- access-to-subprogram type, and that is used as an actual
1504 -- in an instantiation is left to the enthusiastic reader.
1514 -- If there are previous overloadable entities with the same name, check
1515 -- whether any of them is completed by the null procedure.
1517 if Present (Prev) and then Is_Overloadable (Prev) then
1518 Designator := Analyze_Subprogram_Specification (Spec);
1519 Prev := Find_Corresponding_Spec (N);
1522 if No (Prev) or else not Comes_From_Source (Prev) then
1523 Designator := Analyze_Subprogram_Specification (Spec);
1524 Set_Has_Completion (Designator);
1526 -- Signal to caller that this is a procedure declaration
1528 Is_Completion := False;
1530 -- Null procedures are always inlined, but generic formal subprograms
1531 -- which appear as such in the internal instance of formal packages,
1532 -- need no completion and are not marked Inline.
1535 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1537 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1538 Set_Body_To_Inline (N, Null_Body);
1539 Set_Is_Inlined (Designator);
1543 -- The null procedure is a completion. We unconditionally rewrite
1544 -- this as a null body (even if expansion is not active), because
1545 -- there are various error checks that are applied on this body
1546 -- when it is analyzed (e.g. correct aspect placement).
1548 if Has_Completion (Prev) then
1549 Error_Msg_Sloc := Sloc (Prev);
1550 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1553 Check_Previous_Null_Procedure (N, Prev);
1555 Is_Completion := True;
1556 Rewrite (N, Null_Body);
1561 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
1562 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1563 end Analyze_Null_Procedure;
1565 -----------------------------
1566 -- Analyze_Operator_Symbol --
1567 -----------------------------
1569 -- An operator symbol such as "+" or "and" may appear in context where the
1570 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1571 -- is just a string, as in (conjunction = "or"). In these cases the parser
1572 -- generates this node, and the semantics does the disambiguation. Other
1573 -- such case are actuals in an instantiation, the generic unit in an
1574 -- instantiation, and pragma arguments.
1576 procedure Analyze_Operator_Symbol (N : Node_Id) is
1577 Par : constant Node_Id := Parent (N);
1580 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1581 or else Nkind (Par) = N_Function_Instantiation
1582 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1583 or else (Nkind (Par) = N_Pragma_Argument_Association
1584 and then not Is_Pragma_String_Literal (Par))
1585 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1586 or else (Nkind (Par) = N_Attribute_Reference
1587 and then Attribute_Name (Par) /= Name_Value)
1589 Find_Direct_Name (N);
1592 Change_Operator_Symbol_To_String_Literal (N);
1595 end Analyze_Operator_Symbol;
1597 -----------------------------------
1598 -- Analyze_Parameter_Association --
1599 -----------------------------------
1601 procedure Analyze_Parameter_Association (N : Node_Id) is
1603 Analyze (Explicit_Actual_Parameter (N));
1604 end Analyze_Parameter_Association;
1606 ----------------------------
1607 -- Analyze_Procedure_Call --
1608 ----------------------------
1610 -- WARNING: This routine manages Ghost regions. Return statements must be
1611 -- replaced by gotos that jump to the end of the routine and restore the
1614 procedure Analyze_Procedure_Call (N : Node_Id) is
1615 procedure Analyze_Call_And_Resolve;
1616 -- Do Analyze and Resolve calls for procedure call. At the end, check
1617 -- for illegal order dependence.
1618 -- ??? where is the check for illegal order dependencies?
1620 ------------------------------
1621 -- Analyze_Call_And_Resolve --
1622 ------------------------------
1624 procedure Analyze_Call_And_Resolve is
1626 if Nkind (N) = N_Procedure_Call_Statement then
1628 Resolve (N, Standard_Void_Type);
1632 end Analyze_Call_And_Resolve;
1636 Actuals : constant List_Id := Parameter_Associations (N);
1637 Loc : constant Source_Ptr := Sloc (N);
1638 P : constant Node_Id := Name (N);
1640 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1641 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1642 -- Save the Ghost-related attributes to restore on exit
1647 -- Start of processing for Analyze_Procedure_Call
1650 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1651 -- a procedure call or an entry call. The prefix may denote an access
1652 -- to subprogram type, in which case an implicit dereference applies.
1653 -- If the prefix is an indexed component (without implicit dereference)
1654 -- then the construct denotes a call to a member of an entire family.
1655 -- If the prefix is a simple name, it may still denote a call to a
1656 -- parameterless member of an entry family. Resolution of these various
1657 -- interpretations is delicate.
1659 -- Do not analyze machine code statements to avoid rejecting them in
1662 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1663 Set_Etype (P, Standard_Void_Type);
1668 -- If this is a call of the form Obj.Op, the call may have been analyzed
1669 -- and possibly rewritten into a block, in which case we are done.
1671 if Analyzed (N) then
1674 -- If there is an error analyzing the name (which may have been
1675 -- rewritten if the original call was in prefix notation) then error
1676 -- has been emitted already, mark node and return.
1678 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1679 Set_Etype (N, Any_Type);
1683 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1684 -- Set the mode now to ensure that any nodes generated during analysis
1685 -- and expansion are properly marked as Ghost.
1687 Mark_And_Set_Ghost_Procedure_Call (N);
1689 -- Otherwise analyze the parameters
1691 if Present (Actuals) then
1692 Actual := First (Actuals);
1694 while Present (Actual) loop
1696 Check_Parameterless_Call (Actual);
1701 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1703 if Nkind (P) = N_Attribute_Reference
1704 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1706 Name_Elab_Subp_Body)
1708 if Present (Actuals) then
1710 ("no parameters allowed for this call", First (Actuals));
1714 Set_Etype (N, Standard_Void_Type);
1717 elsif Is_Entity_Name (P)
1718 and then Is_Record_Type (Etype (Entity (P)))
1719 and then Remote_AST_I_Dereference (P)
1723 elsif Is_Entity_Name (P)
1724 and then Ekind (Entity (P)) /= E_Entry_Family
1726 if Is_Access_Type (Etype (P))
1727 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1728 and then No (Actuals)
1729 and then Comes_From_Source (N)
1731 Error_Msg_N ("missing explicit dereference in call", N);
1734 Analyze_Call_And_Resolve;
1736 -- If the prefix is the simple name of an entry family, this is a
1737 -- parameterless call from within the task body itself.
1739 elsif Is_Entity_Name (P)
1740 and then Nkind (P) = N_Identifier
1741 and then Ekind (Entity (P)) = E_Entry_Family
1742 and then Present (Actuals)
1743 and then No (Next (First (Actuals)))
1745 -- Can be call to parameterless entry family. What appears to be the
1746 -- sole argument is in fact the entry index. Rewrite prefix of node
1747 -- accordingly. Source representation is unchanged by this
1751 Make_Indexed_Component (Loc,
1753 Make_Selected_Component (Loc,
1754 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1755 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1756 Expressions => Actuals);
1757 Set_Name (N, New_N);
1758 Set_Etype (New_N, Standard_Void_Type);
1759 Set_Parameter_Associations (N, No_List);
1760 Analyze_Call_And_Resolve;
1762 elsif Nkind (P) = N_Explicit_Dereference then
1763 if Ekind (Etype (P)) = E_Subprogram_Type then
1764 Analyze_Call_And_Resolve;
1766 Error_Msg_N ("expect access to procedure in call", P);
1769 -- The name can be a selected component or an indexed component that
1770 -- yields an access to subprogram. Such a prefix is legal if the call
1771 -- has parameter associations.
1773 elsif Is_Access_Type (Etype (P))
1774 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1776 if Present (Actuals) then
1777 Analyze_Call_And_Resolve;
1779 Error_Msg_N ("missing explicit dereference in call ", N);
1782 -- If not an access to subprogram, then the prefix must resolve to the
1783 -- name of an entry, entry family, or protected operation.
1785 -- For the case of a simple entry call, P is a selected component where
1786 -- the prefix is the task and the selector name is the entry. A call to
1787 -- a protected procedure will have the same syntax. If the protected
1788 -- object contains overloaded operations, the entity may appear as a
1789 -- function, the context will select the operation whose type is Void.
1791 elsif Nkind (P) = N_Selected_Component
1792 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1796 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1797 -- in prefix notation may still be missing its controlling argument,
1798 -- so perform the transformation now.
1800 if SPARK_Mode = On and then In_Inlined_Body then
1802 Subp : constant Entity_Id := Entity (Selector_Name (P));
1803 Typ : constant Entity_Id := Etype (Prefix (P));
1806 if Is_Tagged_Type (Typ)
1807 and then Present (First_Formal (Subp))
1808 and then (Etype (First_Formal (Subp)) = Typ
1810 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1811 and then Try_Object_Operation (P)
1816 Analyze_Call_And_Resolve;
1821 Analyze_Call_And_Resolve;
1824 elsif Nkind (P) = N_Selected_Component
1825 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1826 and then Present (Actuals)
1827 and then No (Next (First (Actuals)))
1829 -- Can be call to parameterless entry family. What appears to be the
1830 -- sole argument is in fact the entry index. Rewrite prefix of node
1831 -- accordingly. Source representation is unchanged by this
1835 Make_Indexed_Component (Loc,
1836 Prefix => New_Copy (P),
1837 Expressions => Actuals);
1838 Set_Name (N, New_N);
1839 Set_Etype (New_N, Standard_Void_Type);
1840 Set_Parameter_Associations (N, No_List);
1841 Analyze_Call_And_Resolve;
1843 -- For the case of a reference to an element of an entry family, P is
1844 -- an indexed component whose prefix is a selected component (task and
1845 -- entry family), and whose index is the entry family index.
1847 elsif Nkind (P) = N_Indexed_Component
1848 and then Nkind (Prefix (P)) = N_Selected_Component
1849 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1851 Analyze_Call_And_Resolve;
1853 -- If the prefix is the name of an entry family, it is a call from
1854 -- within the task body itself.
1856 elsif Nkind (P) = N_Indexed_Component
1857 and then Nkind (Prefix (P)) = N_Identifier
1858 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1861 Make_Selected_Component (Loc,
1863 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1864 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1865 Rewrite (Prefix (P), New_N);
1867 Analyze_Call_And_Resolve;
1869 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1870 -- procedure name, so the construct can only be a qualified expression.
1872 elsif Nkind (P) = N_Qualified_Expression
1873 and then Ada_Version >= Ada_2012
1875 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1878 -- Anything else is an error
1881 Error_Msg_N ("invalid procedure or entry call", N);
1885 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1886 end Analyze_Procedure_Call;
1888 ------------------------------
1889 -- Analyze_Return_Statement --
1890 ------------------------------
1892 procedure Analyze_Return_Statement (N : Node_Id) is
1893 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
1894 N_Simple_Return_Statement));
1896 Returns_Object : constant Boolean :=
1897 Nkind (N) = N_Extended_Return_Statement
1899 (Nkind (N) = N_Simple_Return_Statement
1900 and then Present (Expression (N)));
1901 -- True if we're returning something; that is, "return <expression>;"
1902 -- or "return Result : T [:= ...]". False for "return;". Used for error
1903 -- checking: If Returns_Object is True, N should apply to a function
1904 -- body; otherwise N should apply to a procedure body, entry body,
1905 -- accept statement, or extended return statement.
1907 function Find_What_It_Applies_To return Entity_Id;
1908 -- Find the entity representing the innermost enclosing body, accept
1909 -- statement, or extended return statement. If the result is a callable
1910 -- construct or extended return statement, then this will be the value
1911 -- of the Return_Applies_To attribute. Otherwise, the program is
1912 -- illegal. See RM-6.5(4/2).
1914 -----------------------------
1915 -- Find_What_It_Applies_To --
1916 -----------------------------
1918 function Find_What_It_Applies_To return Entity_Id is
1919 Result : Entity_Id := Empty;
1922 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1923 -- and postconditions.
1925 for J in reverse 0 .. Scope_Stack.Last loop
1926 Result := Scope_Stack.Table (J).Entity;
1927 exit when not Ekind_In (Result, E_Block, E_Loop)
1928 and then Chars (Result) /= Name_uPostconditions;
1931 pragma Assert (Present (Result));
1933 end Find_What_It_Applies_To;
1935 -- Local declarations
1937 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1938 Kind : constant Entity_Kind := Ekind (Scope_Id);
1939 Loc : constant Source_Ptr := Sloc (N);
1940 Stm_Entity : constant Entity_Id :=
1942 (E_Return_Statement, Current_Scope, Loc, 'R');
1944 -- Start of processing for Analyze_Return_Statement
1947 Set_Return_Statement_Entity (N, Stm_Entity);
1949 Set_Etype (Stm_Entity, Standard_Void_Type);
1950 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1952 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1953 -- (4/2): an inner return statement will apply to this extended return.
1955 if Nkind (N) = N_Extended_Return_Statement then
1956 Push_Scope (Stm_Entity);
1959 -- Check that pragma No_Return is obeyed. Don't complain about the
1960 -- implicitly-generated return that is placed at the end.
1962 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1963 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1966 -- Warn on any unassigned OUT parameters if in procedure
1968 if Ekind (Scope_Id) = E_Procedure then
1969 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1972 -- Check that functions return objects, and other things do not
1974 if Kind = E_Function or else Kind = E_Generic_Function then
1975 if not Returns_Object then
1976 Error_Msg_N ("missing expression in return from function", N);
1979 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1980 if Returns_Object then
1981 Error_Msg_N ("procedure cannot return value (use function)", N);
1984 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1985 if Returns_Object then
1986 if Is_Protected_Type (Scope (Scope_Id)) then
1987 Error_Msg_N ("entry body cannot return value", N);
1989 Error_Msg_N ("accept statement cannot return value", N);
1993 elsif Kind = E_Return_Statement then
1995 -- We are nested within another return statement, which must be an
1996 -- extended_return_statement.
1998 if Returns_Object then
1999 if Nkind (N) = N_Extended_Return_Statement then
2001 ("extended return statement cannot be nested (use `RETURN;`)",
2004 -- Case of a simple return statement with a value inside extended
2005 -- return statement.
2009 ("return nested in extended return statement cannot return "
2010 & "value (use `RETURN;`)", N);
2015 Error_Msg_N ("illegal context for return statement", N);
2018 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2019 Analyze_Function_Return (N);
2021 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2022 Set_Return_Present (Scope_Id);
2025 if Nkind (N) = N_Extended_Return_Statement then
2029 Kill_Current_Values (Last_Assignment_Only => True);
2030 Check_Unreachable_Code (N);
2032 Analyze_Dimension (N);
2033 end Analyze_Return_Statement;
2035 -------------------------------------
2036 -- Analyze_Simple_Return_Statement --
2037 -------------------------------------
2039 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2041 if Present (Expression (N)) then
2042 Mark_Coextensions (N, Expression (N));
2045 Analyze_Return_Statement (N);
2046 end Analyze_Simple_Return_Statement;
2048 -------------------------
2049 -- Analyze_Return_Type --
2050 -------------------------
2052 procedure Analyze_Return_Type (N : Node_Id) is
2053 Designator : constant Entity_Id := Defining_Entity (N);
2054 Typ : Entity_Id := Empty;
2057 -- Normal case where result definition does not indicate an error
2059 if Result_Definition (N) /= Error then
2060 if Nkind (Result_Definition (N)) = N_Access_Definition then
2061 Check_SPARK_05_Restriction
2062 ("access result is not allowed", Result_Definition (N));
2064 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2067 AD : constant Node_Id :=
2068 Access_To_Subprogram_Definition (Result_Definition (N));
2070 if Present (AD) and then Protected_Present (AD) then
2071 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2073 Typ := Access_Definition (N, Result_Definition (N));
2077 Set_Parent (Typ, Result_Definition (N));
2078 Set_Is_Local_Anonymous_Access (Typ);
2079 Set_Etype (Designator, Typ);
2081 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2083 Null_Exclusion_Static_Checks (N);
2085 -- Subtype_Mark case
2088 Find_Type (Result_Definition (N));
2089 Typ := Entity (Result_Definition (N));
2090 Set_Etype (Designator, Typ);
2092 -- Unconstrained array as result is not allowed in SPARK
2094 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2095 Check_SPARK_05_Restriction
2096 ("returning an unconstrained array is not allowed",
2097 Result_Definition (N));
2100 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2102 Null_Exclusion_Static_Checks (N);
2104 -- If a null exclusion is imposed on the result type, then create
2105 -- a null-excluding itype (an access subtype) and use it as the
2106 -- function's Etype. Note that the null exclusion checks are done
2107 -- right before this, because they don't get applied to types that
2108 -- do not come from source.
2110 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2111 Set_Etype (Designator,
2112 Create_Null_Excluding_Itype
2115 Scope_Id => Scope (Current_Scope)));
2117 -- The new subtype must be elaborated before use because
2118 -- it is visible outside of the function. However its base
2119 -- type may not be frozen yet, so the reference that will
2120 -- force elaboration must be attached to the freezing of
2123 -- If the return specification appears on a proper body,
2124 -- the subtype will have been created already on the spec.
2126 if Is_Frozen (Typ) then
2127 if Nkind (Parent (N)) = N_Subprogram_Body
2128 and then Nkind (Parent (Parent (N))) = N_Subunit
2132 Build_Itype_Reference (Etype (Designator), Parent (N));
2136 Ensure_Freeze_Node (Typ);
2139 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2141 Set_Itype (IR, Etype (Designator));
2142 Append_Freeze_Actions (Typ, New_List (IR));
2147 Set_Etype (Designator, Typ);
2150 if Ekind (Typ) = E_Incomplete_Type
2151 or else (Is_Class_Wide_Type (Typ)
2152 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2154 -- AI05-0151: Tagged incomplete types are allowed in all formal
2155 -- parts. Untagged incomplete types are not allowed in bodies.
2156 -- As a consequence, limited views cannot appear in a basic
2157 -- declaration that is itself within a body, because there is
2158 -- no point at which the non-limited view will become visible.
2160 if Ada_Version >= Ada_2012 then
2161 if From_Limited_With (Typ) and then In_Package_Body then
2163 ("invalid use of incomplete type&",
2164 Result_Definition (N), Typ);
2166 -- The return type of a subprogram body cannot be of a
2167 -- formal incomplete type.
2169 elsif Is_Generic_Type (Typ)
2170 and then Nkind (Parent (N)) = N_Subprogram_Body
2173 ("return type cannot be a formal incomplete type",
2174 Result_Definition (N));
2176 elsif Is_Class_Wide_Type (Typ)
2177 and then Is_Generic_Type (Root_Type (Typ))
2178 and then Nkind (Parent (N)) = N_Subprogram_Body
2181 ("return type cannot be a formal incomplete type",
2182 Result_Definition (N));
2184 elsif Is_Tagged_Type (Typ) then
2187 -- Use is legal in a thunk generated for an operation
2188 -- inherited from a progenitor.
2190 elsif Is_Thunk (Designator)
2191 and then Present (Non_Limited_View (Typ))
2195 elsif Nkind (Parent (N)) = N_Subprogram_Body
2196 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2200 ("invalid use of untagged incomplete type&",
2204 -- The type must be completed in the current package. This
2205 -- is checked at the end of the package declaration when
2206 -- Taft-amendment types are identified. If the return type
2207 -- is class-wide, there is no required check, the type can
2208 -- be a bona fide TAT.
2210 if Ekind (Scope (Current_Scope)) = E_Package
2211 and then In_Private_Part (Scope (Current_Scope))
2212 and then not Is_Class_Wide_Type (Typ)
2214 Append_Elmt (Designator, Private_Dependents (Typ));
2219 ("invalid use of incomplete type&", Designator, Typ);
2224 -- Case where result definition does indicate an error
2227 Set_Etype (Designator, Any_Type);
2229 end Analyze_Return_Type;
2231 -----------------------------
2232 -- Analyze_Subprogram_Body --
2233 -----------------------------
2235 procedure Analyze_Subprogram_Body (N : Node_Id) is
2236 Loc : constant Source_Ptr := Sloc (N);
2237 Body_Spec : constant Node_Id := Specification (N);
2238 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2241 if Debug_Flag_C then
2242 Write_Str ("==> subprogram body ");
2243 Write_Name (Chars (Body_Id));
2244 Write_Str (" from ");
2245 Write_Location (Loc);
2250 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2252 -- The real work is split out into the helper, so it can do "return;"
2253 -- without skipping the debug output:
2255 Analyze_Subprogram_Body_Helper (N);
2257 if Debug_Flag_C then
2259 Write_Str ("<== subprogram body ");
2260 Write_Name (Chars (Body_Id));
2261 Write_Str (" from ");
2262 Write_Location (Loc);
2265 end Analyze_Subprogram_Body;
2267 ------------------------------------
2268 -- Analyze_Subprogram_Body_Helper --
2269 ------------------------------------
2271 -- This procedure is called for regular subprogram bodies, generic bodies,
2272 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2273 -- specification matters, and is used to create a proper declaration for
2274 -- the subprogram, or to perform conformance checks.
2276 -- WARNING: This routine manages Ghost regions. Return statements must be
2277 -- replaced by gotos that jump to the end of the routine and restore the
2280 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2281 Body_Spec : Node_Id := Specification (N);
2282 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2283 Loc : constant Source_Ptr := Sloc (N);
2284 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2286 Conformant : Boolean;
2287 Desig_View : Entity_Id := Empty;
2288 Exch_Views : Elist_Id := No_Elist;
2290 Mask_Types : Elist_Id := No_Elist;
2291 Prot_Typ : Entity_Id := Empty;
2292 Spec_Decl : Node_Id := Empty;
2293 Spec_Id : Entity_Id;
2295 Last_Real_Spec_Entity : Entity_Id := Empty;
2296 -- When we analyze a separate spec, the entity chain ends up containing
2297 -- the formals, as well as any itypes generated during analysis of the
2298 -- default expressions for parameters, or the arguments of associated
2299 -- precondition/postcondition pragmas (which are analyzed in the context
2300 -- of the spec since they have visibility on formals).
2302 -- These entities belong with the spec and not the body. However we do
2303 -- the analysis of the body in the context of the spec (again to obtain
2304 -- visibility to the formals), and all the entities generated during
2305 -- this analysis end up also chained to the entity chain of the spec.
2306 -- But they really belong to the body, and there is circuitry to move
2307 -- them from the spec to the body.
2309 -- However, when we do this move, we don't want to move the real spec
2310 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2311 -- variable points to the last real spec entity, so we only move those
2312 -- chained beyond that point. It is initialized to Empty to deal with
2313 -- the case where there is no separate spec.
2315 function Body_Has_Contract return Boolean;
2316 -- Check whether unanalyzed body has an aspect or pragma that may
2317 -- generate a SPARK contract.
2319 function Body_Has_SPARK_Mode_On return Boolean;
2320 -- Check whether SPARK_Mode On applies to the subprogram body, either
2321 -- because it is specified directly on the body, or because it is
2322 -- inherited from the enclosing subprogram or package.
2324 procedure Build_Subprogram_Declaration;
2325 -- Create a matching subprogram declaration for subprogram body N
2327 procedure Check_Anonymous_Return;
2328 -- Ada 2005: if a function returns an access type that denotes a task,
2329 -- or a type that contains tasks, we must create a master entity for
2330 -- the anonymous type, which typically will be used in an allocator
2331 -- in the body of the function.
2333 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2334 -- Look ahead to recognize a pragma that may appear after the body.
2335 -- If there is a previous spec, check that it appears in the same
2336 -- declarative part. If the pragma is Inline_Always, perform inlining
2337 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2338 -- If the body acts as a spec, and inlining is required, we create a
2339 -- subprogram declaration for it, in order to attach the body to inline.
2340 -- If pragma does not appear after the body, check whether there is
2341 -- an inline pragma before any local declarations.
2343 procedure Check_Missing_Return;
2344 -- Checks for a function with a no return statements, and also performs
2345 -- the warning checks implemented by Check_Returns. In formal mode, also
2346 -- verify that a function ends with a RETURN and that a procedure does
2347 -- not contain any RETURN.
2349 function Disambiguate_Spec return Entity_Id;
2350 -- When a primitive is declared between the private view and the full
2351 -- view of a concurrent type which implements an interface, a special
2352 -- mechanism is used to find the corresponding spec of the primitive
2355 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2356 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2357 -- incomplete types coming from a limited context and replace their
2358 -- limited views with the non-limited ones. Return the list of changes
2359 -- to be used to undo the transformation.
2361 function Is_Private_Concurrent_Primitive
2362 (Subp_Id : Entity_Id) return Boolean;
2363 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2364 -- type that implements an interface and has a private view.
2366 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2367 -- N is the body generated for an expression function that is not a
2368 -- completion and Spec_Id the defining entity of its spec. Mark all
2369 -- the not-yet-frozen types referenced by the simple return statement
2370 -- of the function as formally frozen.
2372 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2373 -- Undo the transformation done by Exchange_Limited_Views.
2375 procedure Set_Trivial_Subprogram (N : Node_Id);
2376 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2377 -- subprogram whose body is being analyzed. N is the statement node
2378 -- causing the flag to be set, if the following statement is a return
2379 -- of an entity, we mark the entity as set in source to suppress any
2380 -- warning on the stylized use of function stubs with a dummy return.
2382 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2383 -- Undo the transformation done by Mask_Unfrozen_Types
2385 procedure Verify_Overriding_Indicator;
2386 -- If there was a previous spec, the entity has been entered in the
2387 -- current scope previously. If the body itself carries an overriding
2388 -- indicator, check that it is consistent with the known status of the
2391 -----------------------
2392 -- Body_Has_Contract --
2393 -----------------------
2395 function Body_Has_Contract return Boolean is
2396 Decls : constant List_Id := Declarations (N);
2400 -- Check for aspects that may generate a contract
2402 if Present (Aspect_Specifications (N)) then
2403 Item := First (Aspect_Specifications (N));
2404 while Present (Item) loop
2405 if Is_Subprogram_Contract_Annotation (Item) then
2413 -- Check for pragmas that may generate a contract
2415 if Present (Decls) then
2416 Item := First (Decls);
2417 while Present (Item) loop
2418 if Nkind (Item) = N_Pragma
2419 and then Is_Subprogram_Contract_Annotation (Item)
2429 end Body_Has_Contract;
2431 ----------------------------
2432 -- Body_Has_SPARK_Mode_On --
2433 ----------------------------
2435 function Body_Has_SPARK_Mode_On return Boolean is
2436 Decls : constant List_Id := Declarations (N);
2440 -- Check for SPARK_Mode aspect
2442 if Present (Aspect_Specifications (N)) then
2443 Item := First (Aspect_Specifications (N));
2444 while Present (Item) loop
2445 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2446 return Get_SPARK_Mode_From_Annotation (Item) = On;
2453 -- Check for SPARK_Mode pragma
2455 if Present (Decls) then
2456 Item := First (Decls);
2457 while Present (Item) loop
2459 -- Pragmas that apply to a subprogram body are usually grouped
2460 -- together. Look for a potential pragma SPARK_Mode among them.
2462 if Nkind (Item) = N_Pragma then
2463 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2464 return Get_SPARK_Mode_From_Annotation (Item) = On;
2467 -- Otherwise the first non-pragma declarative item terminates
2468 -- the region where pragma SPARK_Mode may appear.
2478 -- Otherwise, the applicable SPARK_Mode is inherited from the
2479 -- enclosing subprogram or package.
2481 return SPARK_Mode = On;
2482 end Body_Has_SPARK_Mode_On;
2484 ----------------------------------
2485 -- Build_Subprogram_Declaration --
2486 ----------------------------------
2488 procedure Build_Subprogram_Declaration is
2489 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2490 -- Relocate certain categorization pragmas from the declarative list
2491 -- of subprogram body From and insert them after node To. The pragmas
2494 -- Volatile_Function
2495 -- Also copy pragma SPARK_Mode if present in the declarative list
2496 -- of subprogram body From and insert it after node To. This pragma
2497 -- should not be moved, as it applies to the body too.
2503 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2505 Next_Decl : Node_Id;
2508 pragma Assert (Nkind (From) = N_Subprogram_Body);
2510 -- The destination node must be part of a list, as the pragmas are
2511 -- inserted after it.
2513 pragma Assert (Is_List_Member (To));
2515 -- Inspect the declarations of the subprogram body looking for
2516 -- specific pragmas.
2518 Decl := First (Declarations (N));
2519 while Present (Decl) loop
2520 Next_Decl := Next (Decl);
2522 if Nkind (Decl) = N_Pragma then
2523 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2524 Insert_After (To, New_Copy_Tree (Decl));
2526 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2528 Name_Volatile_Function)
2531 Insert_After (To, Decl);
2542 Subp_Decl : Node_Id;
2544 -- Start of processing for Build_Subprogram_Declaration
2547 -- Create a matching subprogram spec using the profile of the body.
2548 -- The structure of the tree is identical, but has new entities for
2549 -- the defining unit name and formal parameters.
2552 Make_Subprogram_Declaration (Loc,
2553 Specification => Copy_Subprogram_Spec (Body_Spec));
2554 Set_Comes_From_Source (Subp_Decl, True);
2556 -- Also mark parameters as coming from source
2558 if Present (Parameter_Specifications (Specification (Subp_Decl))) then
2563 First (Parameter_Specifications (Specification (Subp_Decl)));
2565 while Present (Form) loop
2566 Set_Comes_From_Source (Defining_Identifier (Form), True);
2572 -- Relocate the aspects and relevant pragmas from the subprogram body
2573 -- to the generated spec because it acts as the initial declaration.
2575 Insert_Before (N, Subp_Decl);
2576 Move_Aspects (N, To => Subp_Decl);
2577 Move_Pragmas (N, To => Subp_Decl);
2579 -- Ensure that the generated corresponding spec and original body
2580 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2581 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2582 -- correctly set for local subprograms.
2584 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2586 Analyze (Subp_Decl);
2588 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2589 -- the body since the expander may generate calls using that entity.
2590 -- Required to ensure that Expand_Call rewrites calls to this
2591 -- function by calls to the built procedure.
2593 if Modify_Tree_For_C
2594 and then Nkind (Body_Spec) = N_Function_Specification
2596 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2598 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2599 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2600 Corresponding_Procedure
2601 (Defining_Entity (Specification (Subp_Decl))));
2604 -- Analyze any relocated source pragmas or pragmas created for aspect
2607 Decl := Next (Subp_Decl);
2608 while Present (Decl) loop
2610 -- Stop the search for pragmas once the body has been reached as
2611 -- this terminates the region where pragmas may appear.
2616 elsif Nkind (Decl) = N_Pragma then
2623 Spec_Id := Defining_Entity (Subp_Decl);
2624 Set_Corresponding_Spec (N, Spec_Id);
2626 -- Mark the generated spec as a source construct to ensure that all
2627 -- calls to it are properly registered in ALI files for GNATprove.
2629 Set_Comes_From_Source (Spec_Id, True);
2631 -- Ensure that the specs of the subprogram declaration and its body
2632 -- are identical, otherwise they will appear non-conformant due to
2633 -- rewritings in the default values of formal parameters.
2635 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2636 Set_Specification (N, Body_Spec);
2637 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2638 end Build_Subprogram_Declaration;
2640 ----------------------------
2641 -- Check_Anonymous_Return --
2642 ----------------------------
2644 procedure Check_Anonymous_Return is
2650 if Present (Spec_Id) then
2656 if Ekind (Scop) = E_Function
2657 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2658 and then not Is_Thunk (Scop)
2660 -- Skip internally built functions which handle the case of
2661 -- a null access (see Expand_Interface_Conversion)
2663 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2664 and then not Comes_From_Source (Parent (Scop)))
2666 and then (Has_Task (Designated_Type (Etype (Scop)))
2668 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2670 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2671 and then Expander_Active
2673 -- Avoid cases with no tasking support
2675 and then RTE_Available (RE_Current_Master)
2676 and then not Restriction_Active (No_Task_Hierarchy)
2679 Make_Object_Declaration (Loc,
2680 Defining_Identifier =>
2681 Make_Defining_Identifier (Loc, Name_uMaster),
2682 Constant_Present => True,
2683 Object_Definition =>
2684 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2686 Make_Explicit_Dereference (Loc,
2687 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2689 if Present (Declarations (N)) then
2690 Prepend (Decl, Declarations (N));
2692 Set_Declarations (N, New_List (Decl));
2695 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2696 Set_Has_Master_Entity (Scop);
2698 -- Now mark the containing scope as a task master
2701 while Nkind (Par) /= N_Compilation_Unit loop
2702 Par := Parent (Par);
2703 pragma Assert (Present (Par));
2705 -- If we fall off the top, we are at the outer level, and
2706 -- the environment task is our effective master, so nothing
2710 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2712 Set_Is_Task_Master (Par, True);
2717 end Check_Anonymous_Return;
2719 -------------------------
2720 -- Check_Inline_Pragma --
2721 -------------------------
2723 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2727 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2728 -- True when N is a pragma Inline or Inline_Always that applies
2729 -- to this subprogram.
2731 -----------------------
2732 -- Is_Inline_Pragma --
2733 -----------------------
2735 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2737 if Nkind (N) = N_Pragma
2739 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2740 or else (Pragma_Name_Unmapped (N) = Name_Inline
2742 (Front_End_Inlining or else Optimization_Level > 0)))
2743 and then Present (Pragma_Argument_Associations (N))
2746 Pragma_Arg : Node_Id :=
2747 Expression (First (Pragma_Argument_Associations (N)));
2749 if Nkind (Pragma_Arg) = N_Selected_Component then
2750 Pragma_Arg := Selector_Name (Pragma_Arg);
2753 return Chars (Pragma_Arg) = Chars (Body_Id);
2759 end Is_Inline_Pragma;
2761 -- Start of processing for Check_Inline_Pragma
2764 if not Expander_Active then
2768 if Is_List_Member (N)
2769 and then Present (Next (N))
2770 and then Is_Inline_Pragma (Next (N))
2774 elsif Nkind (N) /= N_Subprogram_Body_Stub
2775 and then Present (Declarations (N))
2776 and then Is_Inline_Pragma (First (Declarations (N)))
2778 Prag := First (Declarations (N));
2784 if Present (Prag) then
2785 if Present (Spec_Id) then
2786 if Is_List_Member (N)
2787 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2788 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2794 -- Create a subprogram declaration, to make treatment uniform.
2795 -- Make the sloc of the subprogram name that of the entity in
2796 -- the body, so that style checks find identical strings.
2799 Subp : constant Entity_Id :=
2800 Make_Defining_Identifier
2801 (Sloc (Body_Id), Chars (Body_Id));
2802 Decl : constant Node_Id :=
2803 Make_Subprogram_Declaration (Loc,
2805 New_Copy_Tree (Specification (N)));
2808 -- Link the body and the generated spec
2810 Set_Corresponding_Body (Decl, Body_Id);
2811 Set_Corresponding_Spec (N, Subp);
2813 Set_Defining_Unit_Name (Specification (Decl), Subp);
2815 -- To ensure proper coverage when body is inlined, indicate
2816 -- whether the subprogram comes from source.
2818 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2820 if Present (First_Formal (Body_Id)) then
2821 Plist := Copy_Parameter_List (Body_Id);
2822 Set_Parameter_Specifications
2823 (Specification (Decl), Plist);
2826 -- Move aspects to the new spec
2828 if Has_Aspects (N) then
2829 Move_Aspects (N, To => Decl);
2832 Insert_Before (N, Decl);
2835 Set_Has_Pragma_Inline (Subp);
2837 if Pragma_Name (Prag) = Name_Inline_Always then
2838 Set_Is_Inlined (Subp);
2839 Set_Has_Pragma_Inline_Always (Subp);
2842 -- Prior to copying the subprogram body to create a template
2843 -- for it for subsequent inlining, remove the pragma from
2844 -- the current body so that the copy that will produce the
2845 -- new body will start from a completely unanalyzed tree.
2847 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2848 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2855 end Check_Inline_Pragma;
2857 --------------------------
2858 -- Check_Missing_Return --
2859 --------------------------
2861 procedure Check_Missing_Return is
2863 Missing_Ret : Boolean;
2866 if Nkind (Body_Spec) = N_Function_Specification then
2867 if Present (Spec_Id) then
2873 if Return_Present (Id) then
2874 Check_Returns (HSS, 'F', Missing_Ret);
2877 Set_Has_Missing_Return (Id);
2880 -- Within a premature instantiation of a package with no body, we
2881 -- build completions of the functions therein, with a Raise
2882 -- statement. No point in complaining about a missing return in
2885 elsif Ekind (Id) = E_Function
2886 and then In_Instance
2887 and then Present (Statements (HSS))
2888 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2892 elsif Is_Generic_Subprogram (Id)
2893 or else not Is_Machine_Code_Subprogram (Id)
2895 Error_Msg_N ("missing RETURN statement in function body", N);
2898 -- If procedure with No_Return, check returns
2900 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2901 if Present (Spec_Id) then
2907 if No_Return (Id) then
2908 Check_Returns (HSS, 'P', Missing_Ret, Id);
2912 -- Special checks in SPARK mode
2914 if Nkind (Body_Spec) = N_Function_Specification then
2916 -- In SPARK mode, last statement of a function should be a return
2919 Stat : constant Node_Id := Last_Source_Statement (HSS);
2922 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2923 N_Extended_Return_Statement)
2925 Check_SPARK_05_Restriction
2926 ("last statement in function should be RETURN", Stat);
2930 -- In SPARK mode, verify that a procedure has no return
2932 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2933 if Present (Spec_Id) then
2939 -- Would be nice to point to return statement here, can we
2940 -- borrow the Check_Returns procedure here ???
2942 if Return_Present (Id) then
2943 Check_SPARK_05_Restriction
2944 ("procedure should not have RETURN", N);
2947 end Check_Missing_Return;
2949 -----------------------
2950 -- Disambiguate_Spec --
2951 -----------------------
2953 function Disambiguate_Spec return Entity_Id is
2954 Priv_Spec : Entity_Id;
2957 procedure Replace_Types (To_Corresponding : Boolean);
2958 -- Depending on the flag, replace the type of formal parameters of
2959 -- Body_Id if it is a concurrent type implementing interfaces with
2960 -- the corresponding record type or the other way around.
2962 procedure Replace_Types (To_Corresponding : Boolean) is
2964 Formal_Typ : Entity_Id;
2967 Formal := First_Formal (Body_Id);
2968 while Present (Formal) loop
2969 Formal_Typ := Etype (Formal);
2971 if Is_Class_Wide_Type (Formal_Typ) then
2972 Formal_Typ := Root_Type (Formal_Typ);
2975 -- From concurrent type to corresponding record
2977 if To_Corresponding then
2978 if Is_Concurrent_Type (Formal_Typ)
2979 and then Present (Corresponding_Record_Type (Formal_Typ))
2982 (Corresponding_Record_Type (Formal_Typ)))
2985 Corresponding_Record_Type (Formal_Typ));
2988 -- From corresponding record to concurrent type
2991 if Is_Concurrent_Record_Type (Formal_Typ)
2992 and then Present (Interfaces (Formal_Typ))
2995 Corresponding_Concurrent_Type (Formal_Typ));
2999 Next_Formal (Formal);
3003 -- Start of processing for Disambiguate_Spec
3006 -- Try to retrieve the specification of the body as is. All error
3007 -- messages are suppressed because the body may not have a spec in
3008 -- its current state.
3010 Spec_N := Find_Corresponding_Spec (N, False);
3012 -- It is possible that this is the body of a primitive declared
3013 -- between a private and a full view of a concurrent type. The
3014 -- controlling parameter of the spec carries the concurrent type,
3015 -- not the corresponding record type as transformed by Analyze_
3016 -- Subprogram_Specification. In such cases, we undo the change
3017 -- made by the analysis of the specification and try to find the
3020 -- Note that wrappers already have their corresponding specs and
3021 -- bodies set during their creation, so if the candidate spec is
3022 -- a wrapper, then we definitely need to swap all types to their
3023 -- original concurrent status.
3026 or else Is_Primitive_Wrapper (Spec_N)
3028 -- Restore all references of corresponding record types to the
3029 -- original concurrent types.
3031 Replace_Types (To_Corresponding => False);
3032 Priv_Spec := Find_Corresponding_Spec (N, False);
3034 -- The current body truly belongs to a primitive declared between
3035 -- a private and a full view. We leave the modified body as is,
3036 -- and return the true spec.
3038 if Present (Priv_Spec)
3039 and then Is_Private_Primitive (Priv_Spec)
3044 -- In case that this is some sort of error, restore the original
3045 -- state of the body.
3047 Replace_Types (To_Corresponding => True);
3051 end Disambiguate_Spec;
3053 ----------------------------
3054 -- Exchange_Limited_Views --
3055 ----------------------------
3057 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3058 Result : Elist_Id := No_Elist;
3060 procedure Detect_And_Exchange (Id : Entity_Id);
3061 -- Determine whether Id's type denotes an incomplete type associated
3062 -- with a limited with clause and exchange the limited view with the
3063 -- non-limited one when available. Note that the non-limited view
3064 -- may exist because of a with_clause in another unit in the context,
3065 -- but cannot be used because the current view of the enclosing unit
3066 -- is still a limited view.
3068 -------------------------
3069 -- Detect_And_Exchange --
3070 -------------------------
3072 procedure Detect_And_Exchange (Id : Entity_Id) is
3073 Typ : constant Entity_Id := Etype (Id);
3075 if From_Limited_With (Typ)
3076 and then Has_Non_Limited_View (Typ)
3077 and then not From_Limited_With (Scope (Typ))
3080 Result := New_Elmt_List;
3083 Prepend_Elmt (Typ, Result);
3084 Prepend_Elmt (Id, Result);
3085 Set_Etype (Id, Non_Limited_View (Typ));
3087 end Detect_And_Exchange;
3093 -- Start of processing for Exchange_Limited_Views
3096 -- Do not process subprogram bodies as they already use the non-
3097 -- limited view of types.
3099 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3103 -- Examine all formals and swap views when applicable
3105 Formal := First_Formal (Subp_Id);
3106 while Present (Formal) loop
3107 Detect_And_Exchange (Formal);
3109 Next_Formal (Formal);
3112 -- Process the return type of a function
3114 if Ekind (Subp_Id) = E_Function then
3115 Detect_And_Exchange (Subp_Id);
3119 end Exchange_Limited_Views;
3121 -------------------------------------
3122 -- Is_Private_Concurrent_Primitive --
3123 -------------------------------------
3125 function Is_Private_Concurrent_Primitive
3126 (Subp_Id : Entity_Id) return Boolean
3128 Formal_Typ : Entity_Id;
3131 if Present (First_Formal (Subp_Id)) then
3132 Formal_Typ := Etype (First_Formal (Subp_Id));
3134 if Is_Concurrent_Record_Type (Formal_Typ) then
3135 if Is_Class_Wide_Type (Formal_Typ) then
3136 Formal_Typ := Root_Type (Formal_Typ);
3139 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3142 -- The type of the first formal is a concurrent tagged type with
3146 Is_Concurrent_Type (Formal_Typ)
3147 and then Is_Tagged_Type (Formal_Typ)
3148 and then Has_Private_Declaration (Formal_Typ);
3152 end Is_Private_Concurrent_Primitive;
3154 -------------------------
3155 -- Mask_Unfrozen_Types --
3156 -------------------------
3158 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3159 Result : Elist_Id := No_Elist;
3161 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3162 -- Mask all types referenced in the subtree rooted at Node
3164 --------------------
3165 -- Mask_Type_Refs --
3166 --------------------
3168 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3169 procedure Mask_Type (Typ : Entity_Id);
3170 -- ??? what does this do?
3176 procedure Mask_Type (Typ : Entity_Id) is
3178 -- Skip Itypes created by the preanalysis
3181 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3186 if not Is_Frozen (Typ) then
3187 if Scope (Typ) /= Current_Scope then
3188 Set_Is_Frozen (Typ);
3189 Append_New_Elmt (Typ, Result);
3191 Freeze_Before (N, Typ);
3196 -- Start of processing for Mask_Type_Refs
3199 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3200 Mask_Type (Etype (Entity (Node)));
3202 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3203 Mask_Type (Scope (Entity (Node)));
3206 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3207 and then Present (Etype (Node))
3209 Mask_Type (Etype (Node));
3215 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3219 Return_Stmt : constant Node_Id :=
3220 First (Statements (Handled_Statement_Sequence (N)));
3222 -- Start of processing for Mask_Unfrozen_Types
3225 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3227 Mask_References (Expression (Return_Stmt));
3230 end Mask_Unfrozen_Types;
3232 ---------------------------
3233 -- Restore_Limited_Views --
3234 ---------------------------
3236 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3237 Elmt : Elmt_Id := First_Elmt (Restore_List);
3241 while Present (Elmt) loop
3244 Set_Etype (Id, Node (Elmt));
3247 end Restore_Limited_Views;
3249 ----------------------------
3250 -- Set_Trivial_Subprogram --
3251 ----------------------------
3253 procedure Set_Trivial_Subprogram (N : Node_Id) is
3254 Nxt : constant Node_Id := Next (N);
3257 Set_Is_Trivial_Subprogram (Body_Id);
3259 if Present (Spec_Id) then
3260 Set_Is_Trivial_Subprogram (Spec_Id);
3264 and then Nkind (Nxt) = N_Simple_Return_Statement
3265 and then No (Next (Nxt))
3266 and then Present (Expression (Nxt))
3267 and then Is_Entity_Name (Expression (Nxt))
3269 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3271 end Set_Trivial_Subprogram;
3273 ---------------------------
3274 -- Unmask_Unfrozen_Types --
3275 ---------------------------
3277 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3278 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3281 while Present (Elmt) loop
3282 Set_Is_Frozen (Node (Elmt), False);
3285 end Unmask_Unfrozen_Types;
3287 ---------------------------------
3288 -- Verify_Overriding_Indicator --
3289 ---------------------------------
3291 procedure Verify_Overriding_Indicator is
3293 if Must_Override (Body_Spec) then
3294 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3295 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3299 elsif not Present (Overridden_Operation (Spec_Id)) then
3301 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3303 -- Overriding indicators aren't allowed for protected subprogram
3304 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3305 -- this to a warning if -gnatd.E is enabled.
3307 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3308 Error_Msg_Warn := Error_To_Warning;
3310 ("<<overriding indicator not allowed for protected "
3311 & "subprogram body", Body_Spec);
3314 elsif Must_Not_Override (Body_Spec) then
3315 if Present (Overridden_Operation (Spec_Id)) then
3317 ("subprogram& overrides inherited operation",
3318 Body_Spec, Spec_Id);
3320 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3321 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3324 ("subprogram& overrides predefined operator ",
3325 Body_Spec, Spec_Id);
3327 -- Overriding indicators aren't allowed for protected subprogram
3328 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3329 -- this to a warning if -gnatd.E is enabled.
3331 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3332 Error_Msg_Warn := Error_To_Warning;
3335 ("<<overriding indicator not allowed "
3336 & "for protected subprogram body", Body_Spec);
3338 -- If this is not a primitive operation, then the overriding
3339 -- indicator is altogether illegal.
3341 elsif not Is_Primitive (Spec_Id) then
3343 ("overriding indicator only allowed "
3344 & "if subprogram is primitive", Body_Spec);
3347 -- If checking the style rule and the operation overrides, then
3348 -- issue a warning about a missing overriding_indicator. Protected
3349 -- subprogram bodies are excluded from this style checking, since
3350 -- they aren't primitives (even though their declarations can
3351 -- override) and aren't allowed to have an overriding_indicator.
3354 and then Present (Overridden_Operation (Spec_Id))
3355 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3357 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3358 Style.Missing_Overriding (N, Body_Id);
3361 and then Can_Override_Operator (Spec_Id)
3362 and then not In_Predefined_Unit (Spec_Id)
3364 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3365 Style.Missing_Overriding (N, Body_Id);
3367 end Verify_Overriding_Indicator;
3371 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3372 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3373 Saved_EA : constant Boolean := Expander_Active;
3374 Saved_ISMP : constant Boolean :=
3375 Ignore_SPARK_Mode_Pragmas_In_Instance;
3376 -- Save the Ghost and SPARK mode-related data to restore on exit
3378 -- Start of processing for Analyze_Subprogram_Body_Helper
3381 -- A [generic] subprogram body freezes the contract of the nearest
3382 -- enclosing package body and all other contracts encountered in the
3383 -- same declarative part up to and excluding the subprogram body:
3385 -- package body Nearest_Enclosing_Package
3386 -- with Refined_State => (State => Constit)
3390 -- procedure Freezes_Enclosing_Package_Body
3391 -- with Refined_Depends => (Input => Constit) ...
3393 -- This ensures that any annotations referenced by the contract of the
3394 -- [generic] subprogram body are available. This form of freezing is
3395 -- decoupled from the usual Freeze_xxx mechanism because it must also
3396 -- work in the context of generics where normal freezing is disabled.
3398 -- Only bodies coming from source should cause this type of freezing.
3399 -- Expression functions that act as bodies and complete an initial
3400 -- declaration must be included in this category, hence the use of
3403 if Comes_From_Source (Original_Node (N)) then
3404 Freeze_Previous_Contracts (N);
3407 -- Generic subprograms are handled separately. They always have a
3408 -- generic specification. Determine whether current scope has a
3409 -- previous declaration.
3411 -- If the subprogram body is defined within an instance of the same
3412 -- name, the instance appears as a package renaming, and will be hidden
3413 -- within the subprogram.
3415 if Present (Prev_Id)
3416 and then not Is_Overloadable (Prev_Id)
3417 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3418 or else Comes_From_Source (Prev_Id))
3420 if Is_Generic_Subprogram (Prev_Id) then
3423 -- A subprogram body is Ghost when it is stand-alone and subject
3424 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3425 -- the mode now to ensure that any nodes generated during analysis
3426 -- and expansion are properly marked as Ghost.
3428 Mark_And_Set_Ghost_Body (N, Spec_Id);
3430 -- If the body completes the initial declaration of a compilation
3431 -- unit which is subject to pragma Elaboration_Checks, set the
3432 -- model specified by the pragma because it applies to all parts
3435 Install_Elaboration_Model (Spec_Id);
3437 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3438 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3440 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3442 if Nkind (N) = N_Subprogram_Body then
3443 HSS := Handled_Statement_Sequence (N);
3444 Check_Missing_Return;
3449 -- Otherwise a previous entity conflicts with the subprogram name.
3450 -- Attempting to enter name will post error.
3453 Enter_Name (Body_Id);
3457 -- Non-generic case, find the subprogram declaration, if one was seen,
3458 -- or enter new overloaded entity in the current scope. If the
3459 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3460 -- part of the context of one of its subunits. No need to redo the
3463 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3467 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3469 if Nkind (N) = N_Subprogram_Body_Stub
3470 or else No (Corresponding_Spec (N))
3472 if Is_Private_Concurrent_Primitive (Body_Id) then
3473 Spec_Id := Disambiguate_Spec;
3475 -- A subprogram body is Ghost when it is stand-alone and
3476 -- subject to pragma Ghost or when the corresponding spec is
3477 -- Ghost. Set the mode now to ensure that any nodes generated
3478 -- during analysis and expansion are properly marked as Ghost.
3480 Mark_And_Set_Ghost_Body (N, Spec_Id);
3482 -- If the body completes a compilation unit which is subject
3483 -- to pragma Elaboration_Checks, set the model specified by
3484 -- the pragma because it applies to all parts of the unit.
3486 Install_Elaboration_Model (Spec_Id);
3489 Spec_Id := Find_Corresponding_Spec (N);
3491 -- A subprogram body is Ghost when it is stand-alone and
3492 -- subject to pragma Ghost or when the corresponding spec is
3493 -- Ghost. Set the mode now to ensure that any nodes generated
3494 -- during analysis and expansion are properly marked as Ghost.
3496 Mark_And_Set_Ghost_Body (N, Spec_Id);
3498 -- If the body completes a compilation unit which is subject
3499 -- to pragma Elaboration_Checks, set the model specified by
3500 -- the pragma because it applies to all parts of the unit.
3502 Install_Elaboration_Model (Spec_Id);
3504 -- In GNATprove mode, if the body has no previous spec, create
3505 -- one so that the inlining machinery can operate properly.
3506 -- Transfer aspects, if any, to the new spec, so that they
3507 -- are legal and can be processed ahead of the body.
3508 -- We make two copies of the given spec, one for the new
3509 -- declaration, and one for the body.
3511 if No (Spec_Id) and then GNATprove_Mode
3513 -- Inlining does not apply during preanalysis of code
3515 and then Full_Analysis
3517 -- Inlining only applies to full bodies, not stubs
3519 and then Nkind (N) /= N_Subprogram_Body_Stub
3521 -- Inlining only applies to bodies in the source code, not to
3522 -- those generated by the compiler. In particular, expression
3523 -- functions, whose body is generated by the compiler, are
3524 -- treated specially by GNATprove.
3526 and then Comes_From_Source (Body_Id)
3528 -- This cannot be done for a compilation unit, which is not
3529 -- in a context where we can insert a new spec.
3531 and then Is_List_Member (N)
3533 -- Inlining only applies to subprograms without contracts,
3534 -- as a contract is a sign that GNATprove should perform a
3535 -- modular analysis of the subprogram instead of a contextual
3536 -- analysis at each call site. The same test is performed in
3537 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3538 -- here in another form (because the contract has not been
3539 -- attached to the body) to avoid front-end errors in case
3540 -- pragmas are used instead of aspects, because the
3541 -- corresponding pragmas in the body would not be transferred
3542 -- to the spec, leading to legality errors.
3544 and then not Body_Has_Contract
3545 and then not Inside_A_Generic
3547 Build_Subprogram_Declaration;
3549 -- If this is a function that returns a constrained array, and
3550 -- we are generating SPARK_For_C, create subprogram declaration
3551 -- to simplify subsequent C generation.
3554 and then Modify_Tree_For_C
3555 and then Nkind (Body_Spec) = N_Function_Specification
3556 and then Is_Array_Type (Etype (Body_Id))
3557 and then Is_Constrained (Etype (Body_Id))
3559 Build_Subprogram_Declaration;
3563 -- If this is a duplicate body, no point in analyzing it
3565 if Error_Posted (N) then
3569 -- A subprogram body should cause freezing of its own declaration,
3570 -- but if there was no previous explicit declaration, then the
3571 -- subprogram will get frozen too late (there may be code within
3572 -- the body that depends on the subprogram having been frozen,
3573 -- such as uses of extra formals), so we force it to be frozen
3574 -- here. Same holds if the body and spec are compilation units.
3575 -- Finally, if the return type is an anonymous access to protected
3576 -- subprogram, it must be frozen before the body because its
3577 -- expansion has generated an equivalent type that is used when
3578 -- elaborating the body.
3580 -- An exception in the case of Ada 2012, AI05-177: The bodies
3581 -- created for expression functions do not freeze.
3584 and then Nkind (Original_Node (N)) /= N_Expression_Function
3586 Freeze_Before (N, Body_Id);
3588 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3589 Freeze_Before (N, Spec_Id);
3591 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3592 Freeze_Before (N, Etype (Body_Id));
3596 Spec_Id := Corresponding_Spec (N);
3598 -- A subprogram body is Ghost when it is stand-alone and subject
3599 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3600 -- the mode now to ensure that any nodes generated during analysis
3601 -- and expansion are properly marked as Ghost.
3603 Mark_And_Set_Ghost_Body (N, Spec_Id);
3605 -- If the body completes the initial declaration of a compilation
3606 -- unit which is subject to pragma Elaboration_Checks, set the
3607 -- model specified by the pragma because it applies to all parts
3610 Install_Elaboration_Model (Spec_Id);
3614 -- Deactivate expansion inside the body of ignored Ghost entities,
3615 -- as this code will ultimately be ignored. This avoids requiring the
3616 -- presence of run-time units which are not needed. Only do this for
3617 -- user entities, as internally generated entitities might still need
3618 -- to be expanded (e.g. those generated for types).
3620 if Present (Ignored_Ghost_Region)
3621 and then Comes_From_Source (Body_Id)
3623 Expander_Active := False;
3626 -- Previously we scanned the body to look for nested subprograms, and
3627 -- rejected an inline directive if nested subprograms were present,
3628 -- because the back-end would generate conflicting symbols for the
3629 -- nested bodies. This is now unnecessary.
3631 -- Look ahead to recognize a pragma Inline that appears after the body
3633 Check_Inline_Pragma (Spec_Id);
3635 -- Deal with special case of a fully private operation in the body of
3636 -- the protected type. We must create a declaration for the subprogram,
3637 -- in order to attach the protected subprogram that will be used in
3638 -- internal calls. We exclude compiler generated bodies from the
3639 -- expander since the issue does not arise for those cases.
3642 and then Comes_From_Source (N)
3643 and then Is_Protected_Type (Current_Scope)
3645 Spec_Id := Build_Private_Protected_Declaration (N);
3648 -- If we are generating C and this is a function returning a constrained
3649 -- array type for which we must create a procedure with an extra out
3650 -- parameter, build and analyze the body now. The procedure declaration
3651 -- has already been created. We reuse the source body of the function,
3652 -- because in an instance it may contain global references that cannot
3653 -- be reanalyzed. The source function itself is not used any further,
3654 -- so we mark it as having a completion. If the subprogram is a stub the
3655 -- transformation is done later, when the proper body is analyzed.
3658 and then Modify_Tree_For_C
3659 and then Present (Spec_Id)
3660 and then Ekind (Spec_Id) = E_Function
3661 and then Nkind (N) /= N_Subprogram_Body_Stub
3662 and then Rewritten_For_C (Spec_Id)
3664 Set_Has_Completion (Spec_Id);
3666 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3669 -- The entity for the created procedure must remain invisible, so it
3670 -- does not participate in resolution of subsequent references to the
3673 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3677 -- If a separate spec is present, then deal with freezing issues
3679 if Present (Spec_Id) then
3680 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3681 Verify_Overriding_Indicator;
3683 -- In general, the spec will be frozen when we start analyzing the
3684 -- body. However, for internally generated operations, such as
3685 -- wrapper functions for inherited operations with controlling
3686 -- results, the spec may not have been frozen by the time we expand
3687 -- the freeze actions that include the bodies. In particular, extra
3688 -- formals for accessibility or for return-in-place may need to be
3689 -- generated. Freeze nodes, if any, are inserted before the current
3690 -- body. These freeze actions are also needed in ASIS mode and in
3691 -- Compile_Only mode to enable the proper back-end type annotations.
3692 -- They are necessary in any case to ensure proper elaboration order
3695 if Nkind (N) = N_Subprogram_Body
3696 and then Was_Expression_Function (N)
3697 and then not Has_Completion (Spec_Id)
3698 and then Serious_Errors_Detected = 0
3699 and then (Expander_Active
3701 or else Operating_Mode = Check_Semantics
3702 or else Is_Ignored_Ghost_Entity (Spec_Id))
3704 -- The body generated for an expression function that is not a
3705 -- completion is a freeze point neither for the profile nor for
3706 -- anything else. That's why, in order to prevent any freezing
3707 -- during analysis, we need to mask types declared outside the
3708 -- expression (and in an outer scope) that are not yet frozen.
3709 -- This also needs to be done in the case of an ignored Ghost
3710 -- expression function, where the expander isn't active.
3712 Set_Is_Frozen (Spec_Id);
3713 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3715 elsif not Is_Frozen (Spec_Id)
3716 and then Serious_Errors_Detected = 0
3718 Set_Has_Delayed_Freeze (Spec_Id);
3719 Freeze_Before (N, Spec_Id);
3723 -- If the subprogram has a class-wide clone, build its body as a copy
3724 -- of the original body, and rewrite body of original subprogram as a
3725 -- wrapper that calls the clone. If N is a stub, this construction will
3726 -- take place when the proper body is analyzed. No action needed if this
3727 -- subprogram has been eliminated.
3729 if Present (Spec_Id)
3730 and then Present (Class_Wide_Clone (Spec_Id))
3731 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3732 and then Nkind (N) /= N_Subprogram_Body_Stub
3733 and then not (Expander_Active and then Is_Eliminated (Spec_Id))
3735 Build_Class_Wide_Clone_Body (Spec_Id, N);
3737 -- This is the new body for the existing primitive operation
3739 Rewrite (N, Build_Class_Wide_Clone_Call
3740 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3741 Set_Has_Completion (Spec_Id, False);
3746 -- Place subprogram on scope stack, and make formals visible. If there
3747 -- is a spec, the visible entity remains that of the spec.
3749 if Present (Spec_Id) then
3750 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3752 if Is_Child_Unit (Spec_Id) then
3753 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3757 Style.Check_Identifier (Body_Id, Spec_Id);
3760 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3761 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3763 if Is_Abstract_Subprogram (Spec_Id) then
3764 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3768 Set_Convention (Body_Id, Convention (Spec_Id));
3769 Set_Has_Completion (Spec_Id);
3771 if Is_Protected_Type (Scope (Spec_Id)) then
3772 Prot_Typ := Scope (Spec_Id);
3775 -- If this is a body generated for a renaming, do not check for
3776 -- full conformance. The check is redundant, because the spec of
3777 -- the body is a copy of the spec in the renaming declaration,
3778 -- and the test can lead to spurious errors on nested defaults.
3780 if Present (Spec_Decl)
3781 and then not Comes_From_Source (N)
3783 (Nkind (Original_Node (Spec_Decl)) =
3784 N_Subprogram_Renaming_Declaration
3785 or else (Present (Corresponding_Body (Spec_Decl))
3787 Nkind (Unit_Declaration_Node
3788 (Corresponding_Body (Spec_Decl))) =
3789 N_Subprogram_Renaming_Declaration))
3793 -- Conversely, the spec may have been generated for specless body
3794 -- with an inline pragma. The entity comes from source, which is
3795 -- both semantically correct and necessary for proper inlining.
3796 -- The subprogram declaration itself is not in the source.
3798 elsif Comes_From_Source (N)
3799 and then Present (Spec_Decl)
3800 and then not Comes_From_Source (Spec_Decl)
3801 and then Has_Pragma_Inline (Spec_Id)
3808 Fully_Conformant, True, Conformant, Body_Id);
3811 -- If the body is not fully conformant, we have to decide if we
3812 -- should analyze it or not. If it has a really messed up profile
3813 -- then we probably should not analyze it, since we will get too
3814 -- many bogus messages.
3816 -- Our decision is to go ahead in the non-fully conformant case
3817 -- only if it is at least mode conformant with the spec. Note
3818 -- that the call to Check_Fully_Conformant has issued the proper
3819 -- error messages to complain about the lack of conformance.
3822 and then not Mode_Conformant (Body_Id, Spec_Id)
3828 -- In the case we are dealing with an expression function we check
3829 -- the formals attached to the spec instead of the body - so we don't
3830 -- reference body formals.
3832 if Spec_Id /= Body_Id
3833 and then not Is_Expression_Function (Spec_Id)
3835 Reference_Body_Formals (Spec_Id, Body_Id);
3838 Set_Ekind (Body_Id, E_Subprogram_Body);
3840 if Nkind (N) = N_Subprogram_Body_Stub then
3841 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3846 Set_Corresponding_Spec (N, Spec_Id);
3848 -- Ada 2005 (AI-345): If the operation is a primitive operation
3849 -- of a concurrent type, the type of the first parameter has been
3850 -- replaced with the corresponding record, which is the proper
3851 -- run-time structure to use. However, within the body there may
3852 -- be uses of the formals that depend on primitive operations
3853 -- of the type (in particular calls in prefixed form) for which
3854 -- we need the original concurrent type. The operation may have
3855 -- several controlling formals, so the replacement must be done
3858 if Comes_From_Source (Spec_Id)
3859 and then Present (First_Entity (Spec_Id))
3860 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3861 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3862 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3863 and then Present (Corresponding_Concurrent_Type
3864 (Etype (First_Entity (Spec_Id))))
3867 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3871 Form := First_Formal (Spec_Id);
3872 while Present (Form) loop
3873 if Etype (Form) = Typ then
3874 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3882 -- Make the formals visible, and place subprogram on scope stack.
3883 -- This is also the point at which we set Last_Real_Spec_Entity
3884 -- to mark the entities which will not be moved to the body.
3886 Install_Formals (Spec_Id);
3887 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3889 -- Within an instance, add local renaming declarations so that
3890 -- gdb can retrieve the values of actuals more easily. This is
3891 -- only relevant if generating code (and indeed we definitely
3892 -- do not want these definitions -gnatc mode, because that would
3895 if Is_Generic_Instance (Spec_Id)
3896 and then Is_Wrapper_Package (Current_Scope)
3897 and then Expander_Active
3899 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3902 Push_Scope (Spec_Id);
3904 -- Make sure that the subprogram is immediately visible. For
3905 -- child units that have no separate spec this is indispensable.
3906 -- Otherwise it is safe albeit redundant.
3908 Set_Is_Immediately_Visible (Spec_Id);
3911 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3912 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3913 Set_Scope (Body_Id, Scope (Spec_Id));
3915 -- Case of subprogram body with no previous spec
3918 -- Check for style warning required
3922 -- Only apply check for source level subprograms for which checks
3923 -- have not been suppressed.
3925 and then Comes_From_Source (Body_Id)
3926 and then not Suppress_Style_Checks (Body_Id)
3928 -- No warnings within an instance
3930 and then not In_Instance
3932 -- No warnings for expression functions
3934 and then Nkind (Original_Node (N)) /= N_Expression_Function
3936 Style.Body_With_No_Spec (N);
3939 New_Overloaded_Entity (Body_Id);
3941 if Nkind (N) /= N_Subprogram_Body_Stub then
3942 Set_Acts_As_Spec (N);
3943 Generate_Definition (Body_Id);
3945 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3947 -- If the body is an entry wrapper created for an entry with
3948 -- preconditions, it must be compiled in the context of the
3949 -- enclosing synchronized object, because it may mention other
3950 -- operations of the type.
3952 if Is_Entry_Wrapper (Body_Id) then
3954 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3957 Install_Declarations (Prot);
3961 Install_Formals (Body_Id);
3963 Push_Scope (Body_Id);
3966 -- For stubs and bodies with no previous spec, generate references to
3969 Generate_Reference_To_Formals (Body_Id);
3972 -- Entry barrier functions are generated outside the protected type and
3973 -- should not carry the SPARK_Mode of the enclosing context.
3975 if Nkind (N) = N_Subprogram_Body
3976 and then Is_Entry_Barrier_Function (N)
3980 -- The body is generated as part of expression function expansion. When
3981 -- the expression function appears in the visible declarations of a
3982 -- package, the body is added to the private declarations. Since both
3983 -- declarative lists may be subject to a different SPARK_Mode, inherit
3984 -- the mode of the spec.
3986 -- package P with SPARK_Mode is
3987 -- function Expr_Func ... is (...); -- original
3988 -- [function Expr_Func ...;] -- generated spec
3991 -- pragma SPARK_Mode (Off);
3992 -- [function Expr_Func ... is return ...;] -- generated body
3993 -- end P; -- mode is ON
3995 elsif not Comes_From_Source (N)
3996 and then Present (Spec_Id)
3997 and then Is_Expression_Function (Spec_Id)
3999 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4000 Set_SPARK_Pragma_Inherited
4001 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4003 -- Set the SPARK_Mode from the current context (may be overwritten later
4004 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4005 -- initially on a stand-alone subprogram body, but is then relocated to
4006 -- a generated corresponding spec. In this scenario the mode is shared
4007 -- between the spec and body.
4009 elsif No (SPARK_Pragma (Body_Id)) then
4010 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4011 Set_SPARK_Pragma_Inherited (Body_Id);
4014 -- A subprogram body may be instantiated or inlined at a later pass.
4015 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4016 -- applied to the initial declaration of the body.
4018 if Present (Spec_Id) then
4019 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4020 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4024 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4025 -- case the body is instantiated or inlined later and out of context.
4026 -- The body uses this attribute to restore the value of the global
4029 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4030 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4032 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4033 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4037 -- Preserve relevant elaboration-related attributes of the context which
4038 -- are no longer available or very expensive to recompute once analysis,
4039 -- resolution, and expansion are over.
4041 if No (Spec_Id) then
4042 Mark_Elaboration_Attributes
4048 -- If this is the proper body of a stub, we must verify that the stub
4049 -- conforms to the body, and to the previous spec if one was present.
4050 -- We know already that the body conforms to that spec. This test is
4051 -- only required for subprograms that come from source.
4053 if Nkind (Parent (N)) = N_Subunit
4054 and then Comes_From_Source (N)
4055 and then not Error_Posted (Body_Id)
4056 and then Nkind (Corresponding_Stub (Parent (N))) =
4057 N_Subprogram_Body_Stub
4060 Old_Id : constant Entity_Id :=
4062 (Specification (Corresponding_Stub (Parent (N))));
4064 Conformant : Boolean := False;
4067 if No (Spec_Id) then
4068 Check_Fully_Conformant (Body_Id, Old_Id);
4072 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4074 if not Conformant then
4076 -- The stub was taken to be a new declaration. Indicate that
4079 Set_Has_Completion (Old_Id, False);
4085 Set_Has_Completion (Body_Id);
4086 Check_Eliminated (Body_Id);
4088 -- Analyze any aspect specifications that appear on the subprogram body
4089 -- stub. Stop the analysis now as the stub does not have a declarative
4090 -- or a statement part, and it cannot be inlined.
4092 if Nkind (N) = N_Subprogram_Body_Stub then
4093 if Has_Aspects (N) then
4094 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4102 -- Note: Normally we don't do any inlining if expansion is off, since
4103 -- we won't generate code in any case. An exception arises in GNATprove
4104 -- mode where we want to expand some calls in place, even with expansion
4105 -- disabled, since the inlining eases formal verification.
4107 if not GNATprove_Mode
4108 and then Expander_Active
4109 and then Serious_Errors_Detected = 0
4110 and then Present (Spec_Id)
4111 and then Has_Pragma_Inline (Spec_Id)
4113 -- Legacy implementation (relying on front-end inlining)
4115 if not Back_End_Inlining then
4116 if (Has_Pragma_Inline_Always (Spec_Id)
4117 and then not Opt.Disable_FE_Inline_Always)
4118 or else (Front_End_Inlining
4119 and then not Opt.Disable_FE_Inline)
4121 Build_Body_To_Inline (N, Spec_Id);
4124 -- New implementation (relying on back-end inlining)
4127 if Has_Pragma_Inline_Always (Spec_Id)
4128 or else Optimization_Level > 0
4130 -- Handle function returning an unconstrained type
4132 if Comes_From_Source (Body_Id)
4133 and then Ekind (Spec_Id) = E_Function
4134 and then Returns_Unconstrained_Type (Spec_Id)
4136 -- If function builds in place, i.e. returns a limited type,
4137 -- inlining cannot be done.
4139 and then not Is_Limited_Type (Etype (Spec_Id))
4141 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4145 Subp_Body : constant Node_Id :=
4146 Unit_Declaration_Node (Body_Id);
4147 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4150 -- Do not pass inlining to the backend if the subprogram
4151 -- has declarations or statements which cannot be inlined
4152 -- by the backend. This check is done here to emit an
4153 -- error instead of the generic warning message reported
4154 -- by the GCC backend (ie. "function might not be
4157 if Present (Subp_Decl)
4158 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4162 elsif Has_Excluded_Statement
4165 (Handled_Statement_Sequence (Subp_Body)))
4169 -- If the backend inlining is available then at this
4170 -- stage we only have to mark the subprogram as inlined.
4171 -- The expander will take care of registering it in the
4172 -- table of subprograms inlined by the backend a part of
4173 -- processing calls to it (cf. Expand_Call)
4176 Set_Is_Inlined (Spec_Id);
4183 -- In GNATprove mode, inline only when there is a separate subprogram
4184 -- declaration for now, as inlining of subprogram bodies acting as
4185 -- declarations, or subprogram stubs, are not supported by front-end
4186 -- inlining. This inlining should occur after analysis of the body, so
4187 -- that it is known whether the value of SPARK_Mode, which can be
4188 -- defined by a pragma inside the body, is applicable to the body.
4189 -- Inlining can be disabled with switch -gnatdm
4191 elsif GNATprove_Mode
4192 and then Full_Analysis
4193 and then not Inside_A_Generic
4194 and then Present (Spec_Id)
4196 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4197 and then Body_Has_SPARK_Mode_On
4198 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4199 and then not Body_Has_Contract
4200 and then not Debug_Flag_M
4202 Build_Body_To_Inline (N, Spec_Id);
4205 -- When generating code, inherited pre/postconditions are handled when
4206 -- expanding the corresponding contract.
4208 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4209 -- of the specification we have to install the private withed units.
4210 -- This holds for child units as well.
4212 if Is_Compilation_Unit (Body_Id)
4213 or else Nkind (Parent (N)) = N_Compilation_Unit
4215 Install_Private_With_Clauses (Body_Id);
4218 Check_Anonymous_Return;
4220 -- Set the Protected_Formal field of each extra formal of the protected
4221 -- subprogram to reference the corresponding extra formal of the
4222 -- subprogram that implements it. For regular formals this occurs when
4223 -- the protected subprogram's declaration is expanded, but the extra
4224 -- formals don't get created until the subprogram is frozen. We need to
4225 -- do this before analyzing the protected subprogram's body so that any
4226 -- references to the original subprogram's extra formals will be changed
4227 -- refer to the implementing subprogram's formals (see Expand_Formal).
4229 if Present (Spec_Id)
4230 and then Is_Protected_Type (Scope (Spec_Id))
4231 and then Present (Protected_Body_Subprogram (Spec_Id))
4234 Impl_Subp : constant Entity_Id :=
4235 Protected_Body_Subprogram (Spec_Id);
4236 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4237 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4240 while Present (Prot_Ext_Formal) loop
4241 pragma Assert (Present (Impl_Ext_Formal));
4242 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4243 Next_Formal_With_Extras (Prot_Ext_Formal);
4244 Next_Formal_With_Extras (Impl_Ext_Formal);
4249 -- Now we can go on to analyze the body
4251 HSS := Handled_Statement_Sequence (N);
4252 Set_Actual_Subtypes (N, Current_Scope);
4254 -- Add a declaration for the Protection object, renaming declarations
4255 -- for discriminals and privals and finally a declaration for the entry
4256 -- family index (if applicable). This form of early expansion is done
4257 -- when the Expander is active because Install_Private_Data_Declarations
4258 -- references entities which were created during regular expansion. The
4259 -- subprogram entity must come from source, and not be an internally
4260 -- generated subprogram.
4263 and then Present (Prot_Typ)
4264 and then Present (Spec_Id)
4265 and then Comes_From_Source (Spec_Id)
4266 and then not Is_Eliminated (Spec_Id)
4268 Install_Private_Data_Declarations
4269 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4272 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4273 -- may now appear in parameter and result profiles. Since the analysis
4274 -- of a subprogram body may use the parameter and result profile of the
4275 -- spec, swap any limited views with their non-limited counterpart.
4277 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4278 Exch_Views := Exchange_Limited_Views (Spec_Id);
4281 -- If the return type is an anonymous access type whose designated type
4282 -- is the limited view of a class-wide type and the non-limited view is
4283 -- available, update the return type accordingly.
4285 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4291 Rtyp := Etype (Spec_Id);
4293 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4294 Etyp := Directly_Designated_Type (Rtyp);
4296 if Is_Class_Wide_Type (Etyp)
4297 and then From_Limited_With (Etyp)
4300 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4306 -- Analyze any aspect specifications that appear on the subprogram body
4308 if Has_Aspects (N) then
4309 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4312 Analyze_Declarations (Declarations (N));
4314 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4316 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4317 if Present (SPARK_Pragma (Spec_Id)) then
4318 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4320 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4322 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4323 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4324 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4326 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4329 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4333 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4334 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4335 Error_Msg_Sloc := Sloc (Spec_Id);
4337 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4341 -- A subprogram body freezes its own contract. Analyze the contract
4342 -- after the declarations of the body have been processed as pragmas
4343 -- are now chained on the contract of the subprogram body.
4345 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4347 -- Check completion, and analyze the statements
4350 Inspect_Deferred_Constant_Completion (Declarations (N));
4353 -- Deal with end of scope processing for the body
4355 Process_End_Label (HSS, 't', Current_Scope);
4356 Update_Use_Clause_Chain;
4359 -- If we are compiling an entry wrapper, remove the enclosing
4360 -- synchronized object from the stack.
4362 if Is_Entry_Wrapper (Body_Id) then
4366 Check_Subprogram_Order (N);
4367 Set_Analyzed (Body_Id);
4369 -- If we have a separate spec, then the analysis of the declarations
4370 -- caused the entities in the body to be chained to the spec id, but
4371 -- we want them chained to the body id. Only the formal parameters
4372 -- end up chained to the spec id in this case.
4374 if Present (Spec_Id) then
4376 -- We must conform to the categorization of our spec
4378 Validate_Categorization_Dependency (N, Spec_Id);
4380 -- And if this is a child unit, the parent units must conform
4382 if Is_Child_Unit (Spec_Id) then
4383 Validate_Categorization_Dependency
4384 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4387 -- Here is where we move entities from the spec to the body
4389 -- Case where there are entities that stay with the spec
4391 if Present (Last_Real_Spec_Entity) then
4393 -- No body entities (happens when the only real spec entities come
4394 -- from precondition and postcondition pragmas).
4396 if No (Last_Entity (Body_Id)) then
4397 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4399 -- Body entities present (formals), so chain stuff past them
4403 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4406 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4407 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4408 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4410 -- Case where there are no spec entities, in this case there can be
4411 -- no body entities either, so just move everything.
4413 -- If the body is generated for an expression function, it may have
4414 -- been preanalyzed already, if 'access was applied to it.
4417 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4418 N_Expression_Function
4420 pragma Assert (No (Last_Entity (Body_Id)));
4424 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4425 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4426 Set_First_Entity (Spec_Id, Empty);
4427 Set_Last_Entity (Spec_Id, Empty);
4430 -- Otherwise the body does not complete a previous declaration. Check
4431 -- the categorization of the body against the units it withs.
4434 Validate_Categorization_Dependency (N, Body_Id);
4437 Check_Missing_Return;
4439 -- Now we are going to check for variables that are never modified in
4440 -- the body of the procedure. But first we deal with a special case
4441 -- where we want to modify this check. If the body of the subprogram
4442 -- starts with a raise statement or its equivalent, or if the body
4443 -- consists entirely of a null statement, then it is pretty obvious that
4444 -- it is OK to not reference the parameters. For example, this might be
4445 -- the following common idiom for a stubbed function: statement of the
4446 -- procedure raises an exception. In particular this deals with the
4447 -- common idiom of a stubbed function, which appears something like:
4449 -- function F (A : Integer) return Some_Type;
4452 -- raise Program_Error;
4456 -- Here the purpose of X is simply to satisfy the annoying requirement
4457 -- in Ada that there be at least one return, and we certainly do not
4458 -- want to go posting warnings on X that it is not initialized. On
4459 -- the other hand, if X is entirely unreferenced that should still
4462 -- What we do is to detect these cases, and if we find them, flag the
4463 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4464 -- suppress unwanted warnings. For the case of the function stub above
4465 -- we have a special test to set X as apparently assigned to suppress
4472 -- Skip call markers installed by the ABE mechanism, labels, and
4473 -- Push_xxx_Error_Label to find the first real statement.
4475 Stm := First (Statements (HSS));
4476 while Nkind_In (Stm, N_Call_Marker, N_Label)
4477 or else Nkind (Stm) in N_Push_xxx_Label
4482 -- Do the test on the original statement before expansion
4485 Ostm : constant Node_Id := Original_Node (Stm);
4488 -- If explicit raise statement, turn on flag
4490 if Nkind (Ostm) = N_Raise_Statement then
4491 Set_Trivial_Subprogram (Stm);
4493 -- If null statement, and no following statements, turn on flag
4495 elsif Nkind (Stm) = N_Null_Statement
4496 and then Comes_From_Source (Stm)
4497 and then No (Next (Stm))
4499 Set_Trivial_Subprogram (Stm);
4501 -- Check for explicit call cases which likely raise an exception
4503 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4504 if Is_Entity_Name (Name (Ostm)) then
4506 Ent : constant Entity_Id := Entity (Name (Ostm));
4509 -- If the procedure is marked No_Return, then likely it
4510 -- raises an exception, but in any case it is not coming
4511 -- back here, so turn on the flag.
4514 and then Ekind (Ent) = E_Procedure
4515 and then No_Return (Ent)
4517 Set_Trivial_Subprogram (Stm);
4525 -- Check for variables that are never modified
4532 -- If there is a separate spec, then transfer Never_Set_In_Source
4533 -- flags from out parameters to the corresponding entities in the
4534 -- body. The reason we do that is we want to post error flags on
4535 -- the body entities, not the spec entities.
4537 if Present (Spec_Id) then
4538 E1 := First_Entity (Spec_Id);
4539 while Present (E1) loop
4540 if Ekind (E1) = E_Out_Parameter then
4541 E2 := First_Entity (Body_Id);
4542 while Present (E2) loop
4543 exit when Chars (E1) = Chars (E2);
4547 if Present (E2) then
4548 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4556 -- Check references of the subprogram spec when we are dealing with
4557 -- an expression function due to it having a generated body.
4558 -- Otherwise, we simply check the formals of the subprogram body.
4560 if Present (Spec_Id)
4561 and then Is_Expression_Function (Spec_Id)
4563 Check_References (Spec_Id);
4565 Check_References (Body_Id);
4569 -- Check for nested subprogram, and mark outer level subprogram if so
4575 if Present (Spec_Id) then
4582 Ent := Enclosing_Subprogram (Ent);
4583 exit when No (Ent) or else Is_Subprogram (Ent);
4586 if Present (Ent) then
4587 Set_Has_Nested_Subprogram (Ent);
4591 -- Restore the limited views in the spec, if any, to let the back end
4592 -- process it without running into circularities.
4594 if Exch_Views /= No_Elist then
4595 Restore_Limited_Views (Exch_Views);
4598 if Mask_Types /= No_Elist then
4599 Unmask_Unfrozen_Types (Mask_Types);
4602 if Present (Desig_View) then
4603 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4607 if Present (Ignored_Ghost_Region) then
4608 Expander_Active := Saved_EA;
4611 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4612 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4613 end Analyze_Subprogram_Body_Helper;
4615 ------------------------------------
4616 -- Analyze_Subprogram_Declaration --
4617 ------------------------------------
4619 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4620 Scop : constant Entity_Id := Current_Scope;
4621 Designator : Entity_Id;
4623 Is_Completion : Boolean;
4624 -- Indicates whether a null procedure declaration is a completion
4627 -- Null procedures are not allowed in SPARK
4629 if Nkind (Specification (N)) = N_Procedure_Specification
4630 and then Null_Present (Specification (N))
4632 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4634 -- Null procedures are allowed in protected types, following the
4635 -- recent AI12-0147.
4637 if Is_Protected_Type (Current_Scope)
4638 and then Ada_Version < Ada_2012
4640 Error_Msg_N ("protected operation cannot be a null procedure", N);
4643 Analyze_Null_Procedure (N, Is_Completion);
4645 -- The null procedure acts as a body, nothing further is needed
4647 if Is_Completion then
4652 Designator := Analyze_Subprogram_Specification (Specification (N));
4654 -- A reference may already have been generated for the unit name, in
4655 -- which case the following call is redundant. However it is needed for
4656 -- declarations that are the rewriting of an expression function.
4658 Generate_Definition (Designator);
4660 -- Set the SPARK mode from the current context (may be overwritten later
4661 -- with explicit pragma). This is not done for entry barrier functions
4662 -- because they are generated outside the protected type and should not
4663 -- carry the mode of the enclosing context.
4665 if Nkind (N) = N_Subprogram_Declaration
4666 and then Is_Entry_Barrier_Function (N)
4671 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4672 Set_SPARK_Pragma_Inherited (Designator);
4675 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4676 -- the body of this subprogram is instantiated or inlined later and out
4677 -- of context. The body uses this attribute to restore the value of the
4680 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4681 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4684 -- Preserve relevant elaboration-related attributes of the context which
4685 -- are no longer available or very expensive to recompute once analysis,
4686 -- resolution, and expansion are over.
4688 Mark_Elaboration_Attributes
4689 (N_Id => Designator,
4693 if Debug_Flag_C then
4694 Write_Str ("==> subprogram spec ");
4695 Write_Name (Chars (Designator));
4696 Write_Str (" from ");
4697 Write_Location (Sloc (N));
4702 Validate_RCI_Subprogram_Declaration (N);
4703 New_Overloaded_Entity (Designator);
4704 Check_Delayed_Subprogram (Designator);
4706 -- If the type of the first formal of the current subprogram is a non-
4707 -- generic tagged private type, mark the subprogram as being a private
4708 -- primitive. Ditto if this is a function with controlling result, and
4709 -- the return type is currently private. In both cases, the type of the
4710 -- controlling argument or result must be in the current scope for the
4711 -- operation to be primitive.
4713 if Has_Controlling_Result (Designator)
4714 and then Is_Private_Type (Etype (Designator))
4715 and then Scope (Etype (Designator)) = Current_Scope
4716 and then not Is_Generic_Actual_Type (Etype (Designator))
4718 Set_Is_Private_Primitive (Designator);
4720 elsif Present (First_Formal (Designator)) then
4722 Formal_Typ : constant Entity_Id :=
4723 Etype (First_Formal (Designator));
4725 Set_Is_Private_Primitive (Designator,
4726 Is_Tagged_Type (Formal_Typ)
4727 and then Scope (Formal_Typ) = Current_Scope
4728 and then Is_Private_Type (Formal_Typ)
4729 and then not Is_Generic_Actual_Type (Formal_Typ));
4733 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4736 if Ada_Version >= Ada_2005
4737 and then Comes_From_Source (N)
4738 and then Is_Dispatching_Operation (Designator)
4745 if Has_Controlling_Result (Designator) then
4746 Etyp := Etype (Designator);
4749 E := First_Entity (Designator);
4751 and then Is_Formal (E)
4752 and then not Is_Controlling_Formal (E)
4760 if Is_Access_Type (Etyp) then
4761 Etyp := Directly_Designated_Type (Etyp);
4764 if Is_Interface (Etyp)
4765 and then not Is_Abstract_Subprogram (Designator)
4766 and then not (Ekind (Designator) = E_Procedure
4767 and then Null_Present (Specification (N)))
4769 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4771 -- Specialize error message based on procedures vs. functions,
4772 -- since functions can't be null subprograms.
4774 if Ekind (Designator) = E_Procedure then
4776 ("interface procedure % must be abstract or null", N);
4779 ("interface function % must be abstract", N);
4785 -- What is the following code for, it used to be
4787 -- ??? Set_Suppress_Elaboration_Checks
4788 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4790 -- The following seems equivalent, but a bit dubious
4792 if Elaboration_Checks_Suppressed (Designator) then
4793 Set_Kill_Elaboration_Checks (Designator);
4796 -- For a compilation unit, set body required. This flag will only be
4797 -- reset if a valid Import or Interface pragma is processed later on.
4799 if Nkind (Parent (N)) = N_Compilation_Unit then
4800 Set_Body_Required (Parent (N), True);
4802 if Ada_Version >= Ada_2005
4803 and then Nkind (Specification (N)) = N_Procedure_Specification
4804 and then Null_Present (Specification (N))
4807 ("null procedure cannot be declared at library level", N);
4811 Generate_Reference_To_Formals (Designator);
4812 Check_Eliminated (Designator);
4814 if Debug_Flag_C then
4816 Write_Str ("<== subprogram spec ");
4817 Write_Name (Chars (Designator));
4818 Write_Str (" from ");
4819 Write_Location (Sloc (N));
4823 -- Indicate that this is a protected operation, because it may be used
4824 -- in subsequent declarations within the protected type.
4826 if Is_Protected_Type (Current_Scope) then
4827 Set_Convention (Designator, Convention_Protected);
4830 List_Inherited_Pre_Post_Aspects (Designator);
4832 -- Process the aspects before establishing the proper categorization in
4833 -- case the subprogram is a compilation unit and one of its aspects is
4834 -- converted into a categorization pragma.
4836 if Has_Aspects (N) then
4837 Analyze_Aspect_Specifications (N, Designator);
4840 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4841 Set_Categorization_From_Scope (Designator, Scop);
4843 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4844 -- proper categorization of the unit based on its pragmas.
4847 Push_Scope (Designator);
4848 Set_Categorization_From_Pragmas (N);
4849 Validate_Categorization_Dependency (N, Designator);
4852 end Analyze_Subprogram_Declaration;
4854 --------------------------------------
4855 -- Analyze_Subprogram_Specification --
4856 --------------------------------------
4858 -- Reminder: N here really is a subprogram specification (not a subprogram
4859 -- declaration). This procedure is called to analyze the specification in
4860 -- both subprogram bodies and subprogram declarations (specs).
4862 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4863 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4864 -- Determine whether entity E denotes the spec or body of an invariant
4867 ------------------------------------
4868 -- Is_Invariant_Procedure_Or_Body --
4869 ------------------------------------
4871 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4872 Decl : constant Node_Id := Unit_Declaration_Node (E);
4876 if Nkind (Decl) = N_Subprogram_Body then
4877 Spec := Corresponding_Spec (Decl);
4884 and then Ekind (Spec) = E_Procedure
4885 and then (Is_Partial_Invariant_Procedure (Spec)
4886 or else Is_Invariant_Procedure (Spec));
4887 end Is_Invariant_Procedure_Or_Body;
4891 Designator : constant Entity_Id := Defining_Entity (N);
4892 Formals : constant List_Id := Parameter_Specifications (N);
4894 -- Start of processing for Analyze_Subprogram_Specification
4897 -- User-defined operator is not allowed in SPARK, except as a renaming
4899 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4900 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4902 Check_SPARK_05_Restriction
4903 ("user-defined operator is not allowed", N);
4906 -- Proceed with analysis. Do not emit a cross-reference entry if the
4907 -- specification comes from an expression function, because it may be
4908 -- the completion of a previous declaration. If it is not, the cross-
4909 -- reference entry will be emitted for the new subprogram declaration.
4911 if Nkind (Parent (N)) /= N_Expression_Function then
4912 Generate_Definition (Designator);
4915 if Nkind (N) = N_Function_Specification then
4916 Set_Ekind (Designator, E_Function);
4917 Set_Mechanism (Designator, Default_Mechanism);
4919 Set_Ekind (Designator, E_Procedure);
4920 Set_Etype (Designator, Standard_Void_Type);
4923 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4924 -- those subprograms which could be inlined in GNATprove mode (because
4925 -- Body_To_Inline is non-Empty) but should not be inlined.
4927 if GNATprove_Mode then
4928 Set_Is_Inlined_Always (Designator);
4931 -- Introduce new scope for analysis of the formals and the return type
4933 Set_Scope (Designator, Current_Scope);
4935 if Present (Formals) then
4936 Push_Scope (Designator);
4937 Process_Formals (Formals, N);
4939 -- Check dimensions in N for formals with default expression
4941 Analyze_Dimension_Formals (N, Formals);
4943 -- Ada 2005 (AI-345): If this is an overriding operation of an
4944 -- inherited interface operation, and the controlling type is
4945 -- a synchronized type, replace the type with its corresponding
4946 -- record, to match the proper signature of an overriding operation.
4947 -- Same processing for an access parameter whose designated type is
4948 -- derived from a synchronized interface.
4950 -- This modification is not done for invariant procedures because
4951 -- the corresponding record may not necessarely be visible when the
4952 -- concurrent type acts as the full view of a private type.
4955 -- type Prot is private with Type_Invariant => ...;
4956 -- procedure ConcInvariant (Obj : Prot);
4958 -- protected type Prot is ...;
4959 -- type Concurrent_Record_Prot is record ...;
4960 -- procedure ConcInvariant (Obj : Prot) is
4962 -- end ConcInvariant;
4965 -- In the example above, both the spec and body of the invariant
4966 -- procedure must utilize the private type as the controlling type.
4968 if Ada_Version >= Ada_2005
4969 and then not Is_Invariant_Procedure_Or_Body (Designator)
4973 Formal_Typ : Entity_Id;
4974 Rec_Typ : Entity_Id;
4975 Desig_Typ : Entity_Id;
4978 Formal := First_Formal (Designator);
4979 while Present (Formal) loop
4980 Formal_Typ := Etype (Formal);
4982 if Is_Concurrent_Type (Formal_Typ)
4983 and then Present (Corresponding_Record_Type (Formal_Typ))
4985 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4987 if Present (Interfaces (Rec_Typ)) then
4988 Set_Etype (Formal, Rec_Typ);
4991 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4992 Desig_Typ := Designated_Type (Formal_Typ);
4994 if Is_Concurrent_Type (Desig_Typ)
4995 and then Present (Corresponding_Record_Type (Desig_Typ))
4997 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4999 if Present (Interfaces (Rec_Typ)) then
5000 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5005 Next_Formal (Formal);
5012 -- The subprogram scope is pushed and popped around the processing of
5013 -- the return type for consistency with call above to Process_Formals
5014 -- (which itself can call Analyze_Return_Type), and to ensure that any
5015 -- itype created for the return type will be associated with the proper
5018 elsif Nkind (N) = N_Function_Specification then
5019 Push_Scope (Designator);
5020 Analyze_Return_Type (N);
5026 if Nkind (N) = N_Function_Specification then
5028 -- Deal with operator symbol case
5030 if Nkind (Designator) = N_Defining_Operator_Symbol then
5031 Valid_Operator_Definition (Designator);
5034 May_Need_Actuals (Designator);
5036 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5037 -- the subprogram is abstract also. This does not apply to renaming
5038 -- declarations, where abstractness is inherited, and to subprogram
5039 -- bodies generated for stream operations, which become renamings as
5042 -- In case of primitives associated with abstract interface types
5043 -- the check is applied later (see Analyze_Subprogram_Declaration).
5045 if not Nkind_In (Original_Node (Parent (N)),
5046 N_Abstract_Subprogram_Declaration,
5047 N_Formal_Abstract_Subprogram_Declaration,
5048 N_Subprogram_Renaming_Declaration)
5050 if Is_Abstract_Type (Etype (Designator))
5051 and then not Is_Interface (Etype (Designator))
5054 ("function that returns abstract type must be abstract", N);
5056 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5057 -- access result whose designated type is abstract.
5059 elsif Ada_Version >= Ada_2012
5060 and then Nkind (Result_Definition (N)) = N_Access_Definition
5062 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5063 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5066 ("function whose access result designates abstract type "
5067 & "must be abstract", N);
5073 end Analyze_Subprogram_Specification;
5075 -----------------------
5076 -- Check_Conformance --
5077 -----------------------
5079 procedure Check_Conformance
5080 (New_Id : Entity_Id;
5082 Ctype : Conformance_Type;
5084 Conforms : out Boolean;
5085 Err_Loc : Node_Id := Empty;
5086 Get_Inst : Boolean := False;
5087 Skip_Controlling_Formals : Boolean := False)
5089 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5090 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5091 -- If Errmsg is True, then processing continues to post an error message
5092 -- for conformance error on given node. Two messages are output. The
5093 -- first message points to the previous declaration with a general "no
5094 -- conformance" message. The second is the detailed reason, supplied as
5095 -- Msg. The parameter N provide information for a possible & insertion
5096 -- in the message, and also provides the location for posting the
5097 -- message in the absence of a specified Err_Loc location.
5099 function Conventions_Match
5101 Id2 : Entity_Id) return Boolean;
5102 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5105 -----------------------
5106 -- Conformance_Error --
5107 -----------------------
5109 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5116 if No (Err_Loc) then
5122 Error_Msg_Sloc := Sloc (Old_Id);
5125 when Type_Conformant =>
5126 Error_Msg_N -- CODEFIX
5127 ("not type conformant with declaration#!", Enode);
5129 when Mode_Conformant =>
5130 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5132 ("not mode conformant with operation inherited#!",
5136 ("not mode conformant with declaration#!", Enode);
5139 when Subtype_Conformant =>
5140 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5142 ("not subtype conformant with operation inherited#!",
5146 ("not subtype conformant with declaration#!", Enode);
5149 when Fully_Conformant =>
5150 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5151 Error_Msg_N -- CODEFIX
5152 ("not fully conformant with operation inherited#!",
5155 Error_Msg_N -- CODEFIX
5156 ("not fully conformant with declaration#!", Enode);
5160 Error_Msg_NE (Msg, Enode, N);
5162 end Conformance_Error;
5164 -----------------------
5165 -- Conventions_Match --
5166 -----------------------
5168 function Conventions_Match
5170 Id2 : Entity_Id) return Boolean
5173 -- Ignore the conventions of anonymous access-to-subprogram types
5174 -- and subprogram types because these are internally generated and
5175 -- the only way these may receive a convention is if they inherit
5176 -- the convention of a related subprogram.
5178 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5181 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5186 -- Otherwise compare the conventions directly
5189 return Convention (Id1) = Convention (Id2);
5191 end Conventions_Match;
5195 Old_Type : constant Entity_Id := Etype (Old_Id);
5196 New_Type : constant Entity_Id := Etype (New_Id);
5197 Old_Formal : Entity_Id;
5198 New_Formal : Entity_Id;
5199 Access_Types_Match : Boolean;
5200 Old_Formal_Base : Entity_Id;
5201 New_Formal_Base : Entity_Id;
5203 -- Start of processing for Check_Conformance
5208 -- We need a special case for operators, since they don't appear
5211 if Ctype = Type_Conformant then
5212 if Ekind (New_Id) = E_Operator
5213 and then Operator_Matches_Spec (New_Id, Old_Id)
5219 -- If both are functions/operators, check return types conform
5221 if Old_Type /= Standard_Void_Type
5223 New_Type /= Standard_Void_Type
5225 -- If we are checking interface conformance we omit controlling
5226 -- arguments and result, because we are only checking the conformance
5227 -- of the remaining parameters.
5229 if Has_Controlling_Result (Old_Id)
5230 and then Has_Controlling_Result (New_Id)
5231 and then Skip_Controlling_Formals
5235 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5236 if Ctype >= Subtype_Conformant
5237 and then not Predicates_Match (Old_Type, New_Type)
5240 ("\predicate of return type does not match!", New_Id);
5243 ("\return type does not match!", New_Id);
5249 -- Ada 2005 (AI-231): In case of anonymous access types check the
5250 -- null-exclusion and access-to-constant attributes match.
5252 if Ada_Version >= Ada_2005
5253 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5255 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5256 or else Is_Access_Constant (Etype (Old_Type)) /=
5257 Is_Access_Constant (Etype (New_Type)))
5259 Conformance_Error ("\return type does not match!", New_Id);
5263 -- If either is a function/operator and the other isn't, error
5265 elsif Old_Type /= Standard_Void_Type
5266 or else New_Type /= Standard_Void_Type
5268 Conformance_Error ("\functions can only match functions!", New_Id);
5272 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5273 -- If this is a renaming as body, refine error message to indicate that
5274 -- the conflict is with the original declaration. If the entity is not
5275 -- frozen, the conventions don't have to match, the one of the renamed
5276 -- entity is inherited.
5278 if Ctype >= Subtype_Conformant then
5279 if not Conventions_Match (Old_Id, New_Id) then
5280 if not Is_Frozen (New_Id) then
5283 elsif Present (Err_Loc)
5284 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5285 and then Present (Corresponding_Spec (Err_Loc))
5287 Error_Msg_Name_1 := Chars (New_Id);
5289 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5290 Conformance_Error ("\prior declaration for% has convention %!");
5293 Conformance_Error ("\calling conventions do not match!");
5298 elsif Is_Formal_Subprogram (Old_Id)
5299 or else Is_Formal_Subprogram (New_Id)
5300 or else (Is_Subprogram (New_Id)
5301 and then Present (Alias (New_Id))
5302 and then Is_Formal_Subprogram (Alias (New_Id)))
5305 ("\formal subprograms are not subtype conformant "
5306 & "(RM 6.3.1 (17/3))");
5310 -- Deal with parameters
5312 -- Note: we use the entity information, rather than going directly
5313 -- to the specification in the tree. This is not only simpler, but
5314 -- absolutely necessary for some cases of conformance tests between
5315 -- operators, where the declaration tree simply does not exist.
5317 Old_Formal := First_Formal (Old_Id);
5318 New_Formal := First_Formal (New_Id);
5319 while Present (Old_Formal) and then Present (New_Formal) loop
5320 if Is_Controlling_Formal (Old_Formal)
5321 and then Is_Controlling_Formal (New_Formal)
5322 and then Skip_Controlling_Formals
5324 -- The controlling formals will have different types when
5325 -- comparing an interface operation with its match, but both
5326 -- or neither must be access parameters.
5328 if Is_Access_Type (Etype (Old_Formal))
5330 Is_Access_Type (Etype (New_Formal))
5332 goto Skip_Controlling_Formal;
5335 ("\access parameter does not match!", New_Formal);
5339 -- Ada 2012: Mode conformance also requires that formal parameters
5340 -- be both aliased, or neither.
5342 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5343 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5345 ("\aliased parameter mismatch!", New_Formal);
5349 if Ctype = Fully_Conformant then
5351 -- Names must match. Error message is more accurate if we do
5352 -- this before checking that the types of the formals match.
5354 if Chars (Old_Formal) /= Chars (New_Formal) then
5355 Conformance_Error ("\name& does not match!", New_Formal);
5357 -- Set error posted flag on new formal as well to stop
5358 -- junk cascaded messages in some cases.
5360 Set_Error_Posted (New_Formal);
5364 -- Null exclusion must match
5366 if Null_Exclusion_Present (Parent (Old_Formal))
5368 Null_Exclusion_Present (Parent (New_Formal))
5370 -- Only give error if both come from source. This should be
5371 -- investigated some time, since it should not be needed ???
5373 if Comes_From_Source (Old_Formal)
5375 Comes_From_Source (New_Formal)
5378 ("\null exclusion for& does not match", New_Formal);
5380 -- Mark error posted on the new formal to avoid duplicated
5381 -- complaint about types not matching.
5383 Set_Error_Posted (New_Formal);
5388 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5389 -- case occurs whenever a subprogram is being renamed and one of its
5390 -- parameters imposes a null exclusion. For example:
5392 -- type T is null record;
5393 -- type Acc_T is access T;
5394 -- subtype Acc_T_Sub is Acc_T;
5396 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5397 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5400 Old_Formal_Base := Etype (Old_Formal);
5401 New_Formal_Base := Etype (New_Formal);
5404 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5405 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5408 Access_Types_Match := Ada_Version >= Ada_2005
5410 -- Ensure that this rule is only applied when New_Id is a
5411 -- renaming of Old_Id.
5413 and then Nkind (Parent (Parent (New_Id))) =
5414 N_Subprogram_Renaming_Declaration
5415 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5416 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5417 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5419 -- Now handle the allowed access-type case
5421 and then Is_Access_Type (Old_Formal_Base)
5422 and then Is_Access_Type (New_Formal_Base)
5424 -- The type kinds must match. The only exception occurs with
5425 -- multiple generics of the form:
5428 -- type F is private; type A is private;
5429 -- type F_Ptr is access F; type A_Ptr is access A;
5430 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5431 -- package F_Pack is ... package A_Pack is
5432 -- package F_Inst is
5433 -- new F_Pack (A, A_Ptr, A_P);
5435 -- When checking for conformance between the parameters of A_P
5436 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5437 -- because the compiler has transformed A_Ptr into a subtype of
5438 -- F_Ptr. We catch this case in the code below.
5440 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5442 (Is_Generic_Type (Old_Formal_Base)
5443 and then Is_Generic_Type (New_Formal_Base)
5444 and then Is_Internal (New_Formal_Base)
5445 and then Etype (Etype (New_Formal_Base)) =
5447 and then Directly_Designated_Type (Old_Formal_Base) =
5448 Directly_Designated_Type (New_Formal_Base)
5449 and then ((Is_Itype (Old_Formal_Base)
5450 and then (Can_Never_Be_Null (Old_Formal_Base)
5451 or else Is_Access_Constant
5454 (Is_Itype (New_Formal_Base)
5455 and then (Can_Never_Be_Null (New_Formal_Base)
5456 or else Is_Access_Constant
5457 (New_Formal_Base))));
5459 -- Types must always match. In the visible part of an instance,
5460 -- usual overloading rules for dispatching operations apply, and
5461 -- we check base types (not the actual subtypes).
5463 if In_Instance_Visible_Part
5464 and then Is_Dispatching_Operation (New_Id)
5466 if not Conforming_Types
5467 (T1 => Base_Type (Etype (Old_Formal)),
5468 T2 => Base_Type (Etype (New_Formal)),
5470 Get_Inst => Get_Inst)
5471 and then not Access_Types_Match
5473 Conformance_Error ("\type of & does not match!", New_Formal);
5477 elsif not Conforming_Types
5478 (T1 => Old_Formal_Base,
5479 T2 => New_Formal_Base,
5481 Get_Inst => Get_Inst)
5482 and then not Access_Types_Match
5484 -- Don't give error message if old type is Any_Type. This test
5485 -- avoids some cascaded errors, e.g. in case of a bad spec.
5487 if Errmsg and then Old_Formal_Base = Any_Type then
5490 if Ctype >= Subtype_Conformant
5492 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5495 ("\predicate of & does not match!", New_Formal);
5498 ("\type of & does not match!", New_Formal);
5500 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5502 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5510 -- For mode conformance, mode must match
5512 if Ctype >= Mode_Conformant then
5513 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5514 if not Ekind_In (New_Id, E_Function, E_Procedure)
5515 or else not Is_Primitive_Wrapper (New_Id)
5517 Conformance_Error ("\mode of & does not match!", New_Formal);
5521 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5523 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5525 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5528 ("\mode of & does not match!", New_Formal);
5535 -- Part of mode conformance for access types is having the same
5536 -- constant modifier.
5538 elsif Access_Types_Match
5539 and then Is_Access_Constant (Old_Formal_Base) /=
5540 Is_Access_Constant (New_Formal_Base)
5543 ("\constant modifier does not match!", New_Formal);
5548 if Ctype >= Subtype_Conformant then
5550 -- Ada 2005 (AI-231): In case of anonymous access types check
5551 -- the null-exclusion and access-to-constant attributes must
5552 -- match. For null exclusion, we test the types rather than the
5553 -- formals themselves, since the attribute is only set reliably
5554 -- on the formals in the Ada 95 case, and we exclude the case
5555 -- where Old_Formal is marked as controlling, to avoid errors
5556 -- when matching completing bodies with dispatching declarations
5557 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5559 if Ada_Version >= Ada_2005
5560 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5561 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5563 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5564 Can_Never_Be_Null (Etype (New_Formal))
5566 not Is_Controlling_Formal (Old_Formal))
5568 Is_Access_Constant (Etype (Old_Formal)) /=
5569 Is_Access_Constant (Etype (New_Formal)))
5571 -- Do not complain if error already posted on New_Formal. This
5572 -- avoids some redundant error messages.
5574 and then not Error_Posted (New_Formal)
5576 -- It is allowed to omit the null-exclusion in case of stream
5577 -- attribute subprograms. We recognize stream subprograms
5578 -- through their TSS-generated suffix.
5581 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5584 if TSS_Name /= TSS_Stream_Read
5585 and then TSS_Name /= TSS_Stream_Write
5586 and then TSS_Name /= TSS_Stream_Input
5587 and then TSS_Name /= TSS_Stream_Output
5589 -- Here we have a definite conformance error. It is worth
5590 -- special casing the error message for the case of a
5591 -- controlling formal (which excludes null).
5593 if Is_Controlling_Formal (New_Formal) then
5594 Error_Msg_Node_2 := Scope (New_Formal);
5596 ("\controlling formal & of & excludes null, "
5597 & "declaration must exclude null as well",
5600 -- Normal case (couldn't we give more detail here???)
5604 ("\type of & does not match!", New_Formal);
5613 -- Full conformance checks
5615 if Ctype = Fully_Conformant then
5617 -- We have checked already that names match
5619 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5621 -- Check default expressions for in parameters
5624 NewD : constant Boolean :=
5625 Present (Default_Value (New_Formal));
5626 OldD : constant Boolean :=
5627 Present (Default_Value (Old_Formal));
5629 if NewD or OldD then
5631 -- The old default value has been analyzed because the
5632 -- current full declaration will have frozen everything
5633 -- before. The new default value has not been analyzed,
5634 -- so analyze it now before we check for conformance.
5637 Push_Scope (New_Id);
5638 Preanalyze_Spec_Expression
5639 (Default_Value (New_Formal), Etype (New_Formal));
5643 if not (NewD and OldD)
5644 or else not Fully_Conformant_Expressions
5645 (Default_Value (Old_Formal),
5646 Default_Value (New_Formal))
5649 ("\default expression for & does not match!",
5658 -- A couple of special checks for Ada 83 mode. These checks are
5659 -- skipped if either entity is an operator in package Standard,
5660 -- or if either old or new instance is not from the source program.
5662 if Ada_Version = Ada_83
5663 and then Sloc (Old_Id) > Standard_Location
5664 and then Sloc (New_Id) > Standard_Location
5665 and then Comes_From_Source (Old_Id)
5666 and then Comes_From_Source (New_Id)
5669 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5670 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5673 -- Explicit IN must be present or absent in both cases. This
5674 -- test is required only in the full conformance case.
5676 if In_Present (Old_Param) /= In_Present (New_Param)
5677 and then Ctype = Fully_Conformant
5680 ("\(Ada 83) IN must appear in both declarations",
5685 -- Grouping (use of comma in param lists) must be the same
5686 -- This is where we catch a misconformance like:
5689 -- A : Integer; B : Integer
5691 -- which are represented identically in the tree except
5692 -- for the setting of the flags More_Ids and Prev_Ids.
5694 if More_Ids (Old_Param) /= More_Ids (New_Param)
5695 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5698 ("\grouping of & does not match!", New_Formal);
5704 -- This label is required when skipping controlling formals
5706 <<Skip_Controlling_Formal>>
5708 Next_Formal (Old_Formal);
5709 Next_Formal (New_Formal);
5712 if Present (Old_Formal) then
5713 Conformance_Error ("\too few parameters!");
5716 elsif Present (New_Formal) then
5717 Conformance_Error ("\too many parameters!", New_Formal);
5720 end Check_Conformance;
5722 -----------------------
5723 -- Check_Conventions --
5724 -----------------------
5726 procedure Check_Conventions (Typ : Entity_Id) is
5727 Ifaces_List : Elist_Id;
5729 procedure Check_Convention (Op : Entity_Id);
5730 -- Verify that the convention of inherited dispatching operation Op is
5731 -- consistent among all subprograms it overrides. In order to minimize
5732 -- the search, Search_From is utilized to designate a specific point in
5733 -- the list rather than iterating over the whole list once more.
5735 ----------------------
5736 -- Check_Convention --
5737 ----------------------
5739 procedure Check_Convention (Op : Entity_Id) is
5740 Op_Conv : constant Convention_Id := Convention (Op);
5741 Iface_Conv : Convention_Id;
5742 Iface_Elmt : Elmt_Id;
5743 Iface_Prim_Elmt : Elmt_Id;
5744 Iface_Prim : Entity_Id;
5747 Iface_Elmt := First_Elmt (Ifaces_List);
5748 while Present (Iface_Elmt) loop
5750 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5751 while Present (Iface_Prim_Elmt) loop
5752 Iface_Prim := Node (Iface_Prim_Elmt);
5753 Iface_Conv := Convention (Iface_Prim);
5755 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5756 and then Iface_Conv /= Op_Conv
5759 ("inconsistent conventions in primitive operations", Typ);
5761 Error_Msg_Name_1 := Chars (Op);
5762 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5763 Error_Msg_Sloc := Sloc (Op);
5765 if Comes_From_Source (Op) or else No (Alias (Op)) then
5766 if not Present (Overridden_Operation (Op)) then
5767 Error_Msg_N ("\\primitive % defined #", Typ);
5770 ("\\overriding operation % with "
5771 & "convention % defined #", Typ);
5774 else pragma Assert (Present (Alias (Op)));
5775 Error_Msg_Sloc := Sloc (Alias (Op));
5776 Error_Msg_N ("\\inherited operation % with "
5777 & "convention % defined #", Typ);
5780 Error_Msg_Name_1 := Chars (Op);
5781 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5782 Error_Msg_Sloc := Sloc (Iface_Prim);
5783 Error_Msg_N ("\\overridden operation % with "
5784 & "convention % defined #", Typ);
5786 -- Avoid cascading errors
5791 Next_Elmt (Iface_Prim_Elmt);
5794 Next_Elmt (Iface_Elmt);
5796 end Check_Convention;
5800 Prim_Op : Entity_Id;
5801 Prim_Op_Elmt : Elmt_Id;
5803 -- Start of processing for Check_Conventions
5806 if not Has_Interfaces (Typ) then
5810 Collect_Interfaces (Typ, Ifaces_List);
5812 -- The algorithm checks every overriding dispatching operation against
5813 -- all the corresponding overridden dispatching operations, detecting
5814 -- differences in conventions.
5816 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5817 while Present (Prim_Op_Elmt) loop
5818 Prim_Op := Node (Prim_Op_Elmt);
5820 -- A small optimization: skip the predefined dispatching operations
5821 -- since they always have the same convention.
5823 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5824 Check_Convention (Prim_Op);
5827 Next_Elmt (Prim_Op_Elmt);
5829 end Check_Conventions;
5831 ------------------------------
5832 -- Check_Delayed_Subprogram --
5833 ------------------------------
5835 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5836 procedure Possible_Freeze (T : Entity_Id);
5837 -- T is the type of either a formal parameter or of the return type. If
5838 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5839 -- itself must be delayed.
5841 ---------------------
5842 -- Possible_Freeze --
5843 ---------------------
5845 procedure Possible_Freeze (T : Entity_Id) is
5846 Scop : constant Entity_Id := Scope (Designator);
5849 -- If the subprogram appears within a package instance (which may be
5850 -- the wrapper package of a subprogram instance) the freeze node for
5851 -- that package will freeze the subprogram at the proper place, so
5852 -- do not emit a freeze node for the subprogram, given that it may
5853 -- appear in the wrong scope.
5855 if Ekind (Scop) = E_Package
5856 and then not Comes_From_Source (Scop)
5857 and then Is_Generic_Instance (Scop)
5861 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5862 Set_Has_Delayed_Freeze (Designator);
5864 elsif Is_Access_Type (T)
5865 and then Has_Delayed_Freeze (Designated_Type (T))
5866 and then not Is_Frozen (Designated_Type (T))
5868 Set_Has_Delayed_Freeze (Designator);
5870 end Possible_Freeze;
5876 -- Start of processing for Check_Delayed_Subprogram
5879 -- All subprograms, including abstract subprograms, may need a freeze
5880 -- node if some formal type or the return type needs one.
5882 Possible_Freeze (Etype (Designator));
5883 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5885 -- Need delayed freeze if any of the formal types themselves need a
5886 -- delayed freeze and are not yet frozen.
5888 F := First_Formal (Designator);
5889 while Present (F) loop
5890 Possible_Freeze (Etype (F));
5891 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5895 -- Mark functions that return by reference. Note that it cannot be done
5896 -- for delayed_freeze subprograms because the underlying returned type
5897 -- may not be known yet (for private types).
5899 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5901 Typ : constant Entity_Id := Etype (Designator);
5902 Utyp : constant Entity_Id := Underlying_Type (Typ);
5905 if Is_Limited_View (Typ) then
5906 Set_Returns_By_Ref (Designator);
5908 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5909 Set_Returns_By_Ref (Designator);
5913 end Check_Delayed_Subprogram;
5915 ------------------------------------
5916 -- Check_Discriminant_Conformance --
5917 ------------------------------------
5919 procedure Check_Discriminant_Conformance
5924 Old_Discr : Entity_Id := First_Discriminant (Prev);
5925 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5926 New_Discr_Id : Entity_Id;
5927 New_Discr_Type : Entity_Id;
5929 procedure Conformance_Error (Msg : String; N : Node_Id);
5930 -- Post error message for conformance error on given node. Two messages
5931 -- are output. The first points to the previous declaration with a
5932 -- general "no conformance" message. The second is the detailed reason,
5933 -- supplied as Msg. The parameter N provide information for a possible
5934 -- & insertion in the message.
5936 -----------------------
5937 -- Conformance_Error --
5938 -----------------------
5940 procedure Conformance_Error (Msg : String; N : Node_Id) is
5942 Error_Msg_Sloc := Sloc (Prev_Loc);
5943 Error_Msg_N -- CODEFIX
5944 ("not fully conformant with declaration#!", N);
5945 Error_Msg_NE (Msg, N, N);
5946 end Conformance_Error;
5948 -- Start of processing for Check_Discriminant_Conformance
5951 while Present (Old_Discr) and then Present (New_Discr) loop
5952 New_Discr_Id := Defining_Identifier (New_Discr);
5954 -- The subtype mark of the discriminant on the full type has not
5955 -- been analyzed so we do it here. For an access discriminant a new
5958 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5960 Access_Definition (N, Discriminant_Type (New_Discr));
5963 Analyze (Discriminant_Type (New_Discr));
5964 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5966 -- Ada 2005: if the discriminant definition carries a null
5967 -- exclusion, create an itype to check properly for consistency
5968 -- with partial declaration.
5970 if Is_Access_Type (New_Discr_Type)
5971 and then Null_Exclusion_Present (New_Discr)
5974 Create_Null_Excluding_Itype
5975 (T => New_Discr_Type,
5976 Related_Nod => New_Discr,
5977 Scope_Id => Current_Scope);
5981 if not Conforming_Types
5982 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5984 Conformance_Error ("type of & does not match!", New_Discr_Id);
5987 -- Treat the new discriminant as an occurrence of the old one,
5988 -- for navigation purposes, and fill in some semantic
5989 -- information, for completeness.
5991 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5992 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5993 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5998 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5999 Conformance_Error ("name & does not match!", New_Discr_Id);
6003 -- Default expressions must match
6006 NewD : constant Boolean :=
6007 Present (Expression (New_Discr));
6008 OldD : constant Boolean :=
6009 Present (Expression (Parent (Old_Discr)));
6012 if NewD or OldD then
6014 -- The old default value has been analyzed and expanded,
6015 -- because the current full declaration will have frozen
6016 -- everything before. The new default values have not been
6017 -- expanded, so expand now to check conformance.
6020 Preanalyze_Spec_Expression
6021 (Expression (New_Discr), New_Discr_Type);
6024 if not (NewD and OldD)
6025 or else not Fully_Conformant_Expressions
6026 (Expression (Parent (Old_Discr)),
6027 Expression (New_Discr))
6031 ("default expression for & does not match!",
6038 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6040 if Ada_Version = Ada_83 then
6042 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6045 -- Grouping (use of comma in param lists) must be the same
6046 -- This is where we catch a misconformance like:
6049 -- A : Integer; B : Integer
6051 -- which are represented identically in the tree except
6052 -- for the setting of the flags More_Ids and Prev_Ids.
6054 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6055 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6058 ("grouping of & does not match!", New_Discr_Id);
6064 Next_Discriminant (Old_Discr);
6068 if Present (Old_Discr) then
6069 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6072 elsif Present (New_Discr) then
6074 ("too many discriminants!", Defining_Identifier (New_Discr));
6077 end Check_Discriminant_Conformance;
6079 ----------------------------
6080 -- Check_Fully_Conformant --
6081 ----------------------------
6083 procedure Check_Fully_Conformant
6084 (New_Id : Entity_Id;
6086 Err_Loc : Node_Id := Empty)
6089 pragma Warnings (Off, Result);
6092 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6093 end Check_Fully_Conformant;
6095 --------------------------
6096 -- Check_Limited_Return --
6097 --------------------------
6099 procedure Check_Limited_Return
6105 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6106 -- replaced by anonymous access results. This is an incompatibility with
6107 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6108 -- controllable with special switch. ???
6110 -- A limited interface that is not immutably limited is OK
6112 if Is_Limited_Interface (R_Type)
6114 not (Is_Task_Interface (R_Type)
6115 or else Is_Protected_Interface (R_Type)
6116 or else Is_Synchronized_Interface (R_Type))
6120 elsif Is_Limited_Type (R_Type)
6121 and then not Is_Interface (R_Type)
6122 and then Comes_From_Source (N)
6123 and then not In_Instance_Body
6124 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6126 -- Error in Ada 2005
6128 if Ada_Version >= Ada_2005
6129 and then not Debug_Flag_Dot_L
6130 and then not GNAT_Mode
6133 ("(Ada 2005) cannot copy object of a limited type "
6134 & "(RM-2005 6.5(5.5/2))", Expr);
6136 if Is_Limited_View (R_Type) then
6138 ("\return by reference not permitted in Ada 2005", Expr);
6141 -- Warn in Ada 95 mode, to give folks a heads up about this
6144 -- In GNAT mode, this is just a warning, to allow it to be evilly
6145 -- turned off. Otherwise it is a real error.
6147 -- In a generic context, simplify the warning because it makes no
6148 -- sense to discuss pass-by-reference or copy.
6150 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6151 if Inside_A_Generic then
6153 ("return of limited object not permitted in Ada 2005 "
6154 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6156 elsif Is_Limited_View (R_Type) then
6158 ("return by reference not permitted in Ada 2005 "
6159 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6162 ("cannot copy object of a limited type in Ada 2005 "
6163 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6166 -- Ada 95 mode, and compatibility warnings disabled
6169 pragma Assert (Ada_Version <= Ada_95);
6170 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6171 return; -- skip continuation messages below
6174 if not Inside_A_Generic then
6176 ("\consider switching to return of access type", Expr);
6177 Explain_Limited_Type (R_Type, Expr);
6180 end Check_Limited_Return;
6182 ---------------------------
6183 -- Check_Mode_Conformant --
6184 ---------------------------
6186 procedure Check_Mode_Conformant
6187 (New_Id : Entity_Id;
6189 Err_Loc : Node_Id := Empty;
6190 Get_Inst : Boolean := False)
6193 pragma Warnings (Off, Result);
6196 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6197 end Check_Mode_Conformant;
6199 --------------------------------
6200 -- Check_Overriding_Indicator --
6201 --------------------------------
6203 procedure Check_Overriding_Indicator
6205 Overridden_Subp : Entity_Id;
6206 Is_Primitive : Boolean)
6212 -- No overriding indicator for literals
6214 if Ekind (Subp) = E_Enumeration_Literal then
6217 elsif Ekind (Subp) = E_Entry then
6218 Decl := Parent (Subp);
6220 -- No point in analyzing a malformed operator
6222 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6223 and then Error_Posted (Subp)
6228 Decl := Unit_Declaration_Node (Subp);
6231 if Nkind_In (Decl, N_Subprogram_Body,
6232 N_Subprogram_Body_Stub,
6233 N_Subprogram_Declaration,
6234 N_Abstract_Subprogram_Declaration,
6235 N_Subprogram_Renaming_Declaration)
6237 Spec := Specification (Decl);
6239 elsif Nkind (Decl) = N_Entry_Declaration then
6246 -- The overriding operation is type conformant with the overridden one,
6247 -- but the names of the formals are not required to match. If the names
6248 -- appear permuted in the overriding operation, this is a possible
6249 -- source of confusion that is worth diagnosing. Controlling formals
6250 -- often carry names that reflect the type, and it is not worthwhile
6251 -- requiring that their names match.
6253 if Present (Overridden_Subp)
6254 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6261 Form1 := First_Formal (Subp);
6262 Form2 := First_Formal (Overridden_Subp);
6264 -- If the overriding operation is a synchronized operation, skip
6265 -- the first parameter of the overridden operation, which is
6266 -- implicit in the new one. If the operation is declared in the
6267 -- body it is not primitive and all formals must match.
6269 if Is_Concurrent_Type (Scope (Subp))
6270 and then Is_Tagged_Type (Scope (Subp))
6271 and then not Has_Completion (Scope (Subp))
6273 Form2 := Next_Formal (Form2);
6276 if Present (Form1) then
6277 Form1 := Next_Formal (Form1);
6278 Form2 := Next_Formal (Form2);
6281 while Present (Form1) loop
6282 if not Is_Controlling_Formal (Form1)
6283 and then Present (Next_Formal (Form2))
6284 and then Chars (Form1) = Chars (Next_Formal (Form2))
6286 Error_Msg_Node_2 := Alias (Overridden_Subp);
6287 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6289 ("& does not match corresponding formal of&#",
6294 Next_Formal (Form1);
6295 Next_Formal (Form2);
6300 -- If there is an overridden subprogram, then check that there is no
6301 -- "not overriding" indicator, and mark the subprogram as overriding.
6302 -- This is not done if the overridden subprogram is marked as hidden,
6303 -- which can occur for the case of inherited controlled operations
6304 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6305 -- subprogram is not itself hidden. (Note: This condition could probably
6306 -- be simplified, leaving out the testing for the specific controlled
6307 -- cases, but it seems safer and clearer this way, and echoes similar
6308 -- special-case tests of this kind in other places.)
6310 if Present (Overridden_Subp)
6311 and then (not Is_Hidden (Overridden_Subp)
6313 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6316 and then Present (Alias (Overridden_Subp))
6317 and then not Is_Hidden (Alias (Overridden_Subp))))
6319 if Must_Not_Override (Spec) then
6320 Error_Msg_Sloc := Sloc (Overridden_Subp);
6322 if Ekind (Subp) = E_Entry then
6324 ("entry & overrides inherited operation #", Spec, Subp);
6327 ("subprogram & overrides inherited operation #", Spec, Subp);
6330 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6331 -- as an extension of Root_Controlled, and thus has a useless Adjust
6332 -- operation. This operation should not be inherited by other limited
6333 -- controlled types. An explicit Adjust for them is not overriding.
6335 elsif Must_Override (Spec)
6336 and then Chars (Overridden_Subp) = Name_Adjust
6337 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6338 and then Present (Alias (Overridden_Subp))
6339 and then In_Predefined_Unit (Alias (Overridden_Subp))
6342 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6343 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6345 elsif Is_Subprogram (Subp) then
6346 if Is_Init_Proc (Subp) then
6349 elsif No (Overridden_Operation (Subp)) then
6351 -- For entities generated by Derive_Subprograms the overridden
6352 -- operation is the inherited primitive (which is available
6353 -- through the attribute alias)
6355 if (Is_Dispatching_Operation (Subp)
6356 or else Is_Dispatching_Operation (Overridden_Subp))
6357 and then not Comes_From_Source (Overridden_Subp)
6358 and then Find_Dispatching_Type (Overridden_Subp) =
6359 Find_Dispatching_Type (Subp)
6360 and then Present (Alias (Overridden_Subp))
6361 and then Comes_From_Source (Alias (Overridden_Subp))
6363 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6364 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6367 Set_Overridden_Operation (Subp, Overridden_Subp);
6368 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6373 -- If primitive flag is set or this is a protected operation, then
6374 -- the operation is overriding at the point of its declaration, so
6375 -- warn if necessary. Otherwise it may have been declared before the
6376 -- operation it overrides and no check is required.
6379 and then not Must_Override (Spec)
6380 and then (Is_Primitive
6381 or else Ekind (Scope (Subp)) = E_Protected_Type)
6383 Style.Missing_Overriding (Decl, Subp);
6386 -- If Subp is an operator, it may override a predefined operation, if
6387 -- it is defined in the same scope as the type to which it applies.
6388 -- In that case Overridden_Subp is empty because of our implicit
6389 -- representation for predefined operators. We have to check whether the
6390 -- signature of Subp matches that of a predefined operator. Note that
6391 -- first argument provides the name of the operator, and the second
6392 -- argument the signature that may match that of a standard operation.
6393 -- If the indicator is overriding, then the operator must match a
6394 -- predefined signature, because we know already that there is no
6395 -- explicit overridden operation.
6397 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6398 if Must_Not_Override (Spec) then
6400 -- If this is not a primitive or a protected subprogram, then
6401 -- "not overriding" is illegal.
6404 and then Ekind (Scope (Subp)) /= E_Protected_Type
6406 Error_Msg_N ("overriding indicator only allowed "
6407 & "if subprogram is primitive", Subp);
6409 elsif Can_Override_Operator (Subp) then
6411 ("subprogram& overrides predefined operator ", Spec, Subp);
6414 elsif Must_Override (Spec) then
6415 if No (Overridden_Operation (Subp))
6416 and then not Can_Override_Operator (Subp)
6418 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6421 elsif not Error_Posted (Subp)
6422 and then Style_Check
6423 and then Can_Override_Operator (Subp)
6424 and then not In_Predefined_Unit (Subp)
6426 -- If style checks are enabled, indicate that the indicator is
6427 -- missing. However, at the point of declaration, the type of
6428 -- which this is a primitive operation may be private, in which
6429 -- case the indicator would be premature.
6431 if Has_Private_Declaration (Etype (Subp))
6432 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6436 Style.Missing_Overriding (Decl, Subp);
6440 elsif Must_Override (Spec) then
6441 if Ekind (Subp) = E_Entry then
6442 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6444 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6447 -- If the operation is marked "not overriding" and it's not primitive
6448 -- then an error is issued, unless this is an operation of a task or
6449 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6450 -- has been specified have already been checked above.
6452 elsif Must_Not_Override (Spec)
6453 and then not Is_Primitive
6454 and then Ekind (Subp) /= E_Entry
6455 and then Ekind (Scope (Subp)) /= E_Protected_Type
6458 ("overriding indicator only allowed if subprogram is primitive",
6462 end Check_Overriding_Indicator;
6468 -- Note: this procedure needs to know far too much about how the expander
6469 -- messes with exceptions. The use of the flag Exception_Junk and the
6470 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6471 -- works, but is not very clean. It would be better if the expansion
6472 -- routines would leave Original_Node working nicely, and we could use
6473 -- Original_Node here to ignore all the peculiar expander messing ???
6475 procedure Check_Returns
6479 Proc : Entity_Id := Empty)
6483 procedure Check_Statement_Sequence (L : List_Id);
6484 -- Internal recursive procedure to check a list of statements for proper
6485 -- termination by a return statement (or a transfer of control or a
6486 -- compound statement that is itself internally properly terminated).
6488 ------------------------------
6489 -- Check_Statement_Sequence --
6490 ------------------------------
6492 procedure Check_Statement_Sequence (L : List_Id) is
6497 function Assert_False return Boolean;
6498 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6499 -- rewritten as a null statement when assertions are off. The assert
6500 -- is not active, but it is still enough to kill the warning.
6506 function Assert_False return Boolean is
6507 Orig : constant Node_Id := Original_Node (Last_Stm);
6510 if Nkind (Orig) = N_Pragma
6511 and then Pragma_Name (Orig) = Name_Assert
6512 and then not Error_Posted (Orig)
6515 Arg : constant Node_Id :=
6516 First (Pragma_Argument_Associations (Orig));
6517 Exp : constant Node_Id := Expression (Arg);
6519 return Nkind (Exp) = N_Identifier
6520 and then Chars (Exp) = Name_False;
6530 Raise_Exception_Call : Boolean;
6531 -- Set True if statement sequence terminated by Raise_Exception call
6532 -- or a Reraise_Occurrence call.
6534 -- Start of processing for Check_Statement_Sequence
6537 Raise_Exception_Call := False;
6539 -- Get last real statement
6541 Last_Stm := Last (L);
6543 -- Deal with digging out exception handler statement sequences that
6544 -- have been transformed by the local raise to goto optimization.
6545 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6546 -- optimization has occurred, we are looking at something like:
6549 -- original stmts in block
6553 -- goto L1; | omitted if No_Exception_Propagation
6558 -- goto L3; -- skip handler when exception not raised
6560 -- <<L1>> -- target label for local exception
6574 -- and what we have to do is to dig out the estmts1 and estmts2
6575 -- sequences (which were the original sequences of statements in
6576 -- the exception handlers) and check them.
6578 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6583 exit when Nkind (Stm) /= N_Block_Statement;
6584 exit when not Exception_Junk (Stm);
6587 exit when Nkind (Stm) /= N_Label;
6588 exit when not Exception_Junk (Stm);
6589 Check_Statement_Sequence
6590 (Statements (Handled_Statement_Sequence (Next (Stm))));
6595 exit when Nkind (Stm) /= N_Goto_Statement;
6596 exit when not Exception_Junk (Stm);
6600 -- Don't count pragmas
6602 while Nkind (Last_Stm) = N_Pragma
6604 -- Don't count call to SS_Release (can happen after Raise_Exception)
6607 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6609 Nkind (Name (Last_Stm)) = N_Identifier
6611 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6613 -- Don't count exception junk
6616 (Nkind_In (Last_Stm, N_Goto_Statement,
6618 N_Object_Declaration)
6619 and then Exception_Junk (Last_Stm))
6620 or else Nkind (Last_Stm) in N_Push_xxx_Label
6621 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6623 -- Inserted code, such as finalization calls, is irrelevant: we only
6624 -- need to check original source.
6626 or else Is_Rewrite_Insertion (Last_Stm)
6631 -- Here we have the "real" last statement
6633 Kind := Nkind (Last_Stm);
6635 -- Transfer of control, OK. Note that in the No_Return procedure
6636 -- case, we already diagnosed any explicit return statements, so
6637 -- we can treat them as OK in this context.
6639 if Is_Transfer (Last_Stm) then
6642 -- Check cases of explicit non-indirect procedure calls
6644 elsif Kind = N_Procedure_Call_Statement
6645 and then Is_Entity_Name (Name (Last_Stm))
6647 -- Check call to Raise_Exception procedure which is treated
6648 -- specially, as is a call to Reraise_Occurrence.
6650 -- We suppress the warning in these cases since it is likely that
6651 -- the programmer really does not expect to deal with the case
6652 -- of Null_Occurrence, and thus would find a warning about a
6653 -- missing return curious, and raising Program_Error does not
6654 -- seem such a bad behavior if this does occur.
6656 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6657 -- behavior will be to raise Constraint_Error (see AI-329).
6659 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6661 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6663 Raise_Exception_Call := True;
6665 -- For Raise_Exception call, test first argument, if it is
6666 -- an attribute reference for a 'Identity call, then we know
6667 -- that the call cannot possibly return.
6670 Arg : constant Node_Id :=
6671 Original_Node (First_Actual (Last_Stm));
6673 if Nkind (Arg) = N_Attribute_Reference
6674 and then Attribute_Name (Arg) = Name_Identity
6681 -- If statement, need to look inside if there is an else and check
6682 -- each constituent statement sequence for proper termination.
6684 elsif Kind = N_If_Statement
6685 and then Present (Else_Statements (Last_Stm))
6687 Check_Statement_Sequence (Then_Statements (Last_Stm));
6688 Check_Statement_Sequence (Else_Statements (Last_Stm));
6690 if Present (Elsif_Parts (Last_Stm)) then
6692 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6695 while Present (Elsif_Part) loop
6696 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6704 -- Case statement, check each case for proper termination
6706 elsif Kind = N_Case_Statement then
6710 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6711 while Present (Case_Alt) loop
6712 Check_Statement_Sequence (Statements (Case_Alt));
6713 Next_Non_Pragma (Case_Alt);
6719 -- Block statement, check its handled sequence of statements
6721 elsif Kind = N_Block_Statement then
6727 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6736 -- Loop statement. If there is an iteration scheme, we can definitely
6737 -- fall out of the loop. Similarly if there is an exit statement, we
6738 -- can fall out. In either case we need a following return.
6740 elsif Kind = N_Loop_Statement then
6741 if Present (Iteration_Scheme (Last_Stm))
6742 or else Has_Exit (Entity (Identifier (Last_Stm)))
6746 -- A loop with no exit statement or iteration scheme is either
6747 -- an infinite loop, or it has some other exit (raise/return).
6748 -- In either case, no warning is required.
6754 -- Timed entry call, check entry call and delay alternatives
6756 -- Note: in expanded code, the timed entry call has been converted
6757 -- to a set of expanded statements on which the check will work
6758 -- correctly in any case.
6760 elsif Kind = N_Timed_Entry_Call then
6762 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6763 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6766 -- If statement sequence of entry call alternative is missing,
6767 -- then we can definitely fall through, and we post the error
6768 -- message on the entry call alternative itself.
6770 if No (Statements (ECA)) then
6773 -- If statement sequence of delay alternative is missing, then
6774 -- we can definitely fall through, and we post the error
6775 -- message on the delay alternative itself.
6777 -- Note: if both ECA and DCA are missing the return, then we
6778 -- post only one message, should be enough to fix the bugs.
6779 -- If not we will get a message next time on the DCA when the
6782 elsif No (Statements (DCA)) then
6785 -- Else check both statement sequences
6788 Check_Statement_Sequence (Statements (ECA));
6789 Check_Statement_Sequence (Statements (DCA));
6794 -- Conditional entry call, check entry call and else part
6796 -- Note: in expanded code, the conditional entry call has been
6797 -- converted to a set of expanded statements on which the check
6798 -- will work correctly in any case.
6800 elsif Kind = N_Conditional_Entry_Call then
6802 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6805 -- If statement sequence of entry call alternative is missing,
6806 -- then we can definitely fall through, and we post the error
6807 -- message on the entry call alternative itself.
6809 if No (Statements (ECA)) then
6812 -- Else check statement sequence and else part
6815 Check_Statement_Sequence (Statements (ECA));
6816 Check_Statement_Sequence (Else_Statements (Last_Stm));
6822 -- If we fall through, issue appropriate message
6826 -- Kill warning if last statement is a raise exception call,
6827 -- or a pragma Assert (False). Note that with assertions enabled,
6828 -- such a pragma has been converted into a raise exception call
6829 -- already, so the Assert_False is for the assertions off case.
6831 if not Raise_Exception_Call and then not Assert_False then
6833 -- In GNATprove mode, it is an error to have a missing return
6835 Error_Msg_Warn := SPARK_Mode /= On;
6837 -- Issue error message or warning
6840 ("RETURN statement missing following this statement<<!",
6843 ("\Program_Error ]<<!", Last_Stm);
6846 -- Note: we set Err even though we have not issued a warning
6847 -- because we still have a case of a missing return. This is
6848 -- an extremely marginal case, probably will never be noticed
6849 -- but we might as well get it right.
6853 -- Otherwise we have the case of a procedure marked No_Return
6856 if not Raise_Exception_Call then
6857 if GNATprove_Mode then
6859 ("implied return after this statement would have raised "
6860 & "Program_Error", Last_Stm);
6862 -- In normal compilation mode, do not warn on a generated call
6863 -- (e.g. in the body of a renaming as completion).
6865 elsif Comes_From_Source (Last_Stm) then
6867 ("implied return after this statement will raise "
6868 & "Program_Error??", Last_Stm);
6871 Error_Msg_Warn := SPARK_Mode /= On;
6873 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6877 RE : constant Node_Id :=
6878 Make_Raise_Program_Error (Sloc (Last_Stm),
6879 Reason => PE_Implicit_Return);
6881 Insert_After (Last_Stm, RE);
6885 end Check_Statement_Sequence;
6887 -- Start of processing for Check_Returns
6891 Check_Statement_Sequence (Statements (HSS));
6893 if Present (Exception_Handlers (HSS)) then
6894 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6895 while Present (Handler) loop
6896 Check_Statement_Sequence (Statements (Handler));
6897 Next_Non_Pragma (Handler);
6902 ----------------------------
6903 -- Check_Subprogram_Order --
6904 ----------------------------
6906 procedure Check_Subprogram_Order (N : Node_Id) is
6908 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6909 -- This is used to check if S1 > S2 in the sense required by this test,
6910 -- for example nameab < namec, but name2 < name10.
6912 -----------------------------
6913 -- Subprogram_Name_Greater --
6914 -----------------------------
6916 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6921 -- Deal with special case where names are identical except for a
6922 -- numerical suffix. These are handled specially, taking the numeric
6923 -- ordering from the suffix into account.
6926 while S1 (L1) in '0' .. '9' loop
6931 while S2 (L2) in '0' .. '9' loop
6935 -- If non-numeric parts non-equal, do straight compare
6937 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6940 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6941 -- that a missing suffix is treated as numeric zero in this test.
6945 while L1 < S1'Last loop
6947 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6951 while L2 < S2'Last loop
6953 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6958 end Subprogram_Name_Greater;
6960 -- Start of processing for Check_Subprogram_Order
6963 -- Check body in alpha order if this is option
6966 and then Style_Check_Order_Subprograms
6967 and then Nkind (N) = N_Subprogram_Body
6968 and then Comes_From_Source (N)
6969 and then In_Extended_Main_Source_Unit (N)
6973 renames Scope_Stack.Table
6974 (Scope_Stack.Last).Last_Subprogram_Name;
6976 Body_Id : constant Entity_Id :=
6977 Defining_Entity (Specification (N));
6980 Get_Decoded_Name_String (Chars (Body_Id));
6983 if Subprogram_Name_Greater
6984 (LSN.all, Name_Buffer (1 .. Name_Len))
6986 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6992 LSN := new String'(Name_Buffer (1 .. Name_Len));
6995 end Check_Subprogram_Order;
6997 ------------------------------
6998 -- Check_Subtype_Conformant --
6999 ------------------------------
7001 procedure Check_Subtype_Conformant
7002 (New_Id : Entity_Id;
7004 Err_Loc : Node_Id := Empty;
7005 Skip_Controlling_Formals : Boolean := False;
7006 Get_Inst : Boolean := False)
7009 pragma Warnings (Off, Result);
7012 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7013 Skip_Controlling_Formals => Skip_Controlling_Formals,
7014 Get_Inst => Get_Inst);
7015 end Check_Subtype_Conformant;
7017 -----------------------------------
7018 -- Check_Synchronized_Overriding --
7019 -----------------------------------
7021 procedure Check_Synchronized_Overriding
7022 (Def_Id : Entity_Id;
7023 Overridden_Subp : out Entity_Id)
7025 Ifaces_List : Elist_Id;
7029 function Matches_Prefixed_View_Profile
7030 (Prim_Params : List_Id;
7031 Iface_Params : List_Id) return Boolean;
7032 -- Determine whether a subprogram's parameter profile Prim_Params
7033 -- matches that of a potentially overridden interface subprogram
7034 -- Iface_Params. Also determine if the type of first parameter of
7035 -- Iface_Params is an implemented interface.
7037 -----------------------------------
7038 -- Matches_Prefixed_View_Profile --
7039 -----------------------------------
7041 function Matches_Prefixed_View_Profile
7042 (Prim_Params : List_Id;
7043 Iface_Params : List_Id) return Boolean
7045 function Is_Implemented
7046 (Ifaces_List : Elist_Id;
7047 Iface : Entity_Id) return Boolean;
7048 -- Determine if Iface is implemented by the current task or
7051 --------------------
7052 -- Is_Implemented --
7053 --------------------
7055 function Is_Implemented
7056 (Ifaces_List : Elist_Id;
7057 Iface : Entity_Id) return Boolean
7059 Iface_Elmt : Elmt_Id;
7062 Iface_Elmt := First_Elmt (Ifaces_List);
7063 while Present (Iface_Elmt) loop
7064 if Node (Iface_Elmt) = Iface then
7068 Next_Elmt (Iface_Elmt);
7076 Iface_Id : Entity_Id;
7077 Iface_Param : Node_Id;
7078 Iface_Typ : Entity_Id;
7079 Prim_Id : Entity_Id;
7080 Prim_Param : Node_Id;
7081 Prim_Typ : Entity_Id;
7083 -- Start of processing for Matches_Prefixed_View_Profile
7086 Iface_Param := First (Iface_Params);
7087 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7089 if Is_Access_Type (Iface_Typ) then
7090 Iface_Typ := Designated_Type (Iface_Typ);
7093 Prim_Param := First (Prim_Params);
7095 -- The first parameter of the potentially overridden subprogram must
7096 -- be an interface implemented by Prim.
7098 if not Is_Interface (Iface_Typ)
7099 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7104 -- The checks on the object parameters are done, so move on to the
7105 -- rest of the parameters.
7107 if not In_Scope then
7108 Prim_Param := Next (Prim_Param);
7111 Iface_Param := Next (Iface_Param);
7112 while Present (Iface_Param) and then Present (Prim_Param) loop
7113 Iface_Id := Defining_Identifier (Iface_Param);
7114 Iface_Typ := Find_Parameter_Type (Iface_Param);
7116 Prim_Id := Defining_Identifier (Prim_Param);
7117 Prim_Typ := Find_Parameter_Type (Prim_Param);
7119 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7120 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7121 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7123 Iface_Typ := Designated_Type (Iface_Typ);
7124 Prim_Typ := Designated_Type (Prim_Typ);
7127 -- Case of multiple interface types inside a parameter profile
7129 -- (Obj_Param : in out Iface; ...; Param : Iface)
7131 -- If the interface type is implemented, then the matching type in
7132 -- the primitive should be the implementing record type.
7134 if Ekind (Iface_Typ) = E_Record_Type
7135 and then Is_Interface (Iface_Typ)
7136 and then Is_Implemented (Ifaces_List, Iface_Typ)
7138 if Prim_Typ /= Typ then
7142 -- The two parameters must be both mode and subtype conformant
7144 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7146 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7155 -- One of the two lists contains more parameters than the other
7157 if Present (Iface_Param) or else Present (Prim_Param) then
7162 end Matches_Prefixed_View_Profile;
7164 -- Start of processing for Check_Synchronized_Overriding
7167 Overridden_Subp := Empty;
7169 -- Def_Id must be an entry or a subprogram. We should skip predefined
7170 -- primitives internally generated by the front end; however at this
7171 -- stage predefined primitives are still not fully decorated. As a
7172 -- minor optimization we skip here internally generated subprograms.
7174 if (Ekind (Def_Id) /= E_Entry
7175 and then Ekind (Def_Id) /= E_Function
7176 and then Ekind (Def_Id) /= E_Procedure)
7177 or else not Comes_From_Source (Def_Id)
7182 -- Search for the concurrent declaration since it contains the list of
7183 -- all implemented interfaces. In this case, the subprogram is declared
7184 -- within the scope of a protected or a task type.
7186 if Present (Scope (Def_Id))
7187 and then Is_Concurrent_Type (Scope (Def_Id))
7188 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7190 Typ := Scope (Def_Id);
7193 -- The enclosing scope is not a synchronized type and the subprogram
7196 elsif No (First_Formal (Def_Id)) then
7199 -- The subprogram has formals and hence it may be a primitive of a
7203 Typ := Etype (First_Formal (Def_Id));
7205 if Is_Access_Type (Typ) then
7206 Typ := Directly_Designated_Type (Typ);
7209 if Is_Concurrent_Type (Typ)
7210 and then not Is_Generic_Actual_Type (Typ)
7214 -- This case occurs when the concurrent type is declared within a
7215 -- generic unit. As a result the corresponding record has been built
7216 -- and used as the type of the first formal, we just have to retrieve
7217 -- the corresponding concurrent type.
7219 elsif Is_Concurrent_Record_Type (Typ)
7220 and then not Is_Class_Wide_Type (Typ)
7221 and then Present (Corresponding_Concurrent_Type (Typ))
7223 Typ := Corresponding_Concurrent_Type (Typ);
7231 -- There is no overriding to check if this is an inherited operation in
7232 -- a type derivation for a generic actual.
7234 Collect_Interfaces (Typ, Ifaces_List);
7236 if Is_Empty_Elmt_List (Ifaces_List) then
7240 -- Determine whether entry or subprogram Def_Id overrides a primitive
7241 -- operation that belongs to one of the interfaces in Ifaces_List.
7244 Candidate : Entity_Id := Empty;
7245 Hom : Entity_Id := Empty;
7246 Subp : Entity_Id := Empty;
7249 -- Traverse the homonym chain, looking for a potentially overridden
7250 -- subprogram that belongs to an implemented interface.
7252 Hom := Current_Entity_In_Scope (Def_Id);
7253 while Present (Hom) loop
7257 or else not Is_Overloadable (Subp)
7258 or else not Is_Primitive (Subp)
7259 or else not Is_Dispatching_Operation (Subp)
7260 or else not Present (Find_Dispatching_Type (Subp))
7261 or else not Is_Interface (Find_Dispatching_Type (Subp))
7265 -- Entries and procedures can override abstract or null interface
7268 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7269 and then Ekind (Subp) = E_Procedure
7270 and then Matches_Prefixed_View_Profile
7271 (Parameter_Specifications (Parent (Def_Id)),
7272 Parameter_Specifications (Parent (Subp)))
7276 -- For an overridden subprogram Subp, check whether the mode
7277 -- of its first parameter is correct depending on the kind of
7278 -- synchronized type.
7281 Formal : constant Node_Id := First_Formal (Candidate);
7284 -- In order for an entry or a protected procedure to
7285 -- override, the first parameter of the overridden routine
7286 -- must be of mode "out", "in out", or access-to-variable.
7288 if Ekind_In (Candidate, E_Entry, E_Procedure)
7289 and then Is_Protected_Type (Typ)
7290 and then Ekind (Formal) /= E_In_Out_Parameter
7291 and then Ekind (Formal) /= E_Out_Parameter
7292 and then Nkind (Parameter_Type (Parent (Formal))) /=
7297 -- All other cases are OK since a task entry or routine does
7298 -- not have a restriction on the mode of the first parameter
7299 -- of the overridden interface routine.
7302 Overridden_Subp := Candidate;
7307 -- Functions can override abstract interface functions. Return
7308 -- types must be subtype conformant.
7310 elsif Ekind (Def_Id) = E_Function
7311 and then Ekind (Subp) = E_Function
7312 and then Matches_Prefixed_View_Profile
7313 (Parameter_Specifications (Parent (Def_Id)),
7314 Parameter_Specifications (Parent (Subp)))
7315 and then Conforming_Types
7316 (Etype (Def_Id), Etype (Subp), Subtype_Conformant)
7320 -- If an inherited subprogram is implemented by a protected
7321 -- function, then the first parameter of the inherited
7322 -- subprogram shall be of mode in, but not an access-to-
7323 -- variable parameter (RM 9.4(11/9)).
7325 if Present (First_Formal (Subp))
7326 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7328 (not Is_Access_Type (Etype (First_Formal (Subp)))
7330 Is_Access_Constant (Etype (First_Formal (Subp))))
7332 Overridden_Subp := Subp;
7337 Hom := Homonym (Hom);
7340 -- After examining all candidates for overriding, we are left with
7341 -- the best match, which is a mode-incompatible interface routine.
7343 if In_Scope and then Present (Candidate) then
7344 Error_Msg_PT (Def_Id, Candidate);
7347 Overridden_Subp := Candidate;
7350 end Check_Synchronized_Overriding;
7352 ---------------------------
7353 -- Check_Type_Conformant --
7354 ---------------------------
7356 procedure Check_Type_Conformant
7357 (New_Id : Entity_Id;
7359 Err_Loc : Node_Id := Empty)
7362 pragma Warnings (Off, Result);
7365 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7366 end Check_Type_Conformant;
7368 ---------------------------
7369 -- Can_Override_Operator --
7370 ---------------------------
7372 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7376 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7380 Typ := Base_Type (Etype (First_Formal (Subp)));
7382 -- Check explicitly that the operation is a primitive of the type
7384 return Operator_Matches_Spec (Subp, Subp)
7385 and then not Is_Generic_Type (Typ)
7386 and then Scope (Subp) = Scope (Typ)
7387 and then not Is_Class_Wide_Type (Typ);
7389 end Can_Override_Operator;
7391 ----------------------
7392 -- Conforming_Types --
7393 ----------------------
7395 function Conforming_Types
7398 Ctype : Conformance_Type;
7399 Get_Inst : Boolean := False) return Boolean
7401 function Base_Types_Match
7403 Typ_2 : Entity_Id) return Boolean;
7404 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7405 -- in different scopes (e.g. parent and child instances), then verify
7406 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7407 -- the same subtype chain. The whole purpose of this procedure is to
7408 -- prevent spurious ambiguities in an instantiation that may arise if
7409 -- two distinct generic types are instantiated with the same actual.
7411 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7412 -- An access parameter can designate an incomplete type. If the
7413 -- incomplete type is the limited view of a type from a limited_
7414 -- with_clause, check whether the non-limited view is available.
7415 -- If it is a (non-limited) incomplete type, get the full view.
7417 function Matches_Limited_With_View
7419 Typ_2 : Entity_Id) return Boolean;
7420 -- Returns True if and only if either Typ_1 denotes a limited view of
7421 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7422 -- the limited with view of a type is used in a subprogram declaration
7423 -- and the subprogram body is in the scope of a regular with clause for
7424 -- the same unit. In such a case, the two type entities are considered
7425 -- identical for purposes of conformance checking.
7427 ----------------------
7428 -- Base_Types_Match --
7429 ----------------------
7431 function Base_Types_Match
7433 Typ_2 : Entity_Id) return Boolean
7435 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7436 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7439 if Typ_1 = Typ_2 then
7442 elsif Base_1 = Base_2 then
7444 -- The following is too permissive. A more precise test should
7445 -- check that the generic actual is an ancestor subtype of the
7448 -- See code in Find_Corresponding_Spec that applies an additional
7449 -- filter to handle accidental amiguities in instances.
7452 not Is_Generic_Actual_Type (Typ_1)
7453 or else not Is_Generic_Actual_Type (Typ_2)
7454 or else Scope (Typ_1) /= Scope (Typ_2);
7456 -- If Typ_2 is a generic actual type it is declared as the subtype of
7457 -- the actual. If that actual is itself a subtype we need to use its
7458 -- own base type to check for compatibility.
7460 elsif Ekind (Base_2) = Ekind (Typ_2)
7461 and then Base_1 = Base_Type (Base_2)
7465 elsif Ekind (Base_1) = Ekind (Typ_1)
7466 and then Base_2 = Base_Type (Base_1)
7473 end Base_Types_Match;
7475 --------------------------
7476 -- Find_Designated_Type --
7477 --------------------------
7479 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7483 Desig := Directly_Designated_Type (Typ);
7485 if Ekind (Desig) = E_Incomplete_Type then
7487 -- If regular incomplete type, get full view if available
7489 if Present (Full_View (Desig)) then
7490 Desig := Full_View (Desig);
7492 -- If limited view of a type, get non-limited view if available,
7493 -- and check again for a regular incomplete type.
7495 elsif Present (Non_Limited_View (Desig)) then
7496 Desig := Get_Full_View (Non_Limited_View (Desig));
7501 end Find_Designated_Type;
7503 -------------------------------
7504 -- Matches_Limited_With_View --
7505 -------------------------------
7507 function Matches_Limited_With_View
7509 Typ_2 : Entity_Id) return Boolean
7511 function Is_Matching_Limited_View
7513 View : Entity_Id) return Boolean;
7514 -- Determine whether non-limited view View denotes type Typ in some
7515 -- conformant fashion.
7517 ------------------------------
7518 -- Is_Matching_Limited_View --
7519 ------------------------------
7521 function Is_Matching_Limited_View
7523 View : Entity_Id) return Boolean
7525 Root_Typ : Entity_Id;
7526 Root_View : Entity_Id;
7529 -- The non-limited view directly denotes the type
7534 -- The type is a subtype of the non-limited view
7536 elsif Is_Subtype_Of (Typ, View) then
7539 -- Both the non-limited view and the type denote class-wide types
7541 elsif Is_Class_Wide_Type (Typ)
7542 and then Is_Class_Wide_Type (View)
7544 Root_Typ := Root_Type (Typ);
7545 Root_View := Root_Type (View);
7547 if Root_Typ = Root_View then
7550 -- An incomplete tagged type and its full view may receive two
7551 -- distinct class-wide types when the related package has not
7552 -- been analyzed yet.
7555 -- type T is tagged; -- CW_1
7556 -- type T is tagged null record; -- CW_2
7559 -- This is because the package lacks any semantic information
7560 -- that may eventually link both views of T. As a consequence,
7561 -- a client of the limited view of Pack will see CW_2 while a
7562 -- client of the non-limited view of Pack will see CW_1.
7564 elsif Is_Incomplete_Type (Root_Typ)
7565 and then Present (Full_View (Root_Typ))
7566 and then Full_View (Root_Typ) = Root_View
7570 elsif Is_Incomplete_Type (Root_View)
7571 and then Present (Full_View (Root_View))
7572 and then Full_View (Root_View) = Root_Typ
7579 end Is_Matching_Limited_View;
7581 -- Start of processing for Matches_Limited_With_View
7584 -- In some cases a type imported through a limited_with clause, and
7585 -- its non-limited view are both visible, for example in an anonymous
7586 -- access-to-class-wide type in a formal, or when building the body
7587 -- for a subprogram renaming after the subprogram has been frozen.
7588 -- In these cases both entities designate the same type. In addition,
7589 -- if one of them is an actual in an instance, it may be a subtype of
7590 -- the non-limited view of the other.
7592 if From_Limited_With (Typ_1)
7593 and then From_Limited_With (Typ_2)
7594 and then Available_View (Typ_1) = Available_View (Typ_2)
7598 elsif From_Limited_With (Typ_1) then
7599 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7601 elsif From_Limited_With (Typ_2) then
7602 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7607 end Matches_Limited_With_View;
7611 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7613 Type_1 : Entity_Id := T1;
7614 Type_2 : Entity_Id := T2;
7616 -- Start of processing for Conforming_Types
7619 -- The context is an instance association for a formal access-to-
7620 -- subprogram type; the formal parameter types require mapping because
7621 -- they may denote other formal parameters of the generic unit.
7624 Type_1 := Get_Instance_Of (T1);
7625 Type_2 := Get_Instance_Of (T2);
7628 -- If one of the types is a view of the other introduced by a limited
7629 -- with clause, treat these as conforming for all purposes.
7631 if Matches_Limited_With_View (T1, T2) then
7634 elsif Base_Types_Match (Type_1, Type_2) then
7635 if Ctype <= Mode_Conformant then
7640 Subtypes_Statically_Match (Type_1, Type_2)
7641 and then Dimensions_Match (Type_1, Type_2);
7644 elsif Is_Incomplete_Or_Private_Type (Type_1)
7645 and then Present (Full_View (Type_1))
7646 and then Base_Types_Match (Full_View (Type_1), Type_2)
7649 Ctype <= Mode_Conformant
7650 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7652 elsif Ekind (Type_2) = E_Incomplete_Type
7653 and then Present (Full_View (Type_2))
7654 and then Base_Types_Match (Type_1, Full_View (Type_2))
7657 Ctype <= Mode_Conformant
7658 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7660 elsif Is_Private_Type (Type_2)
7661 and then In_Instance
7662 and then Present (Full_View (Type_2))
7663 and then Base_Types_Match (Type_1, Full_View (Type_2))
7666 Ctype <= Mode_Conformant
7667 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7669 -- Another confusion between views in a nested instance with an
7670 -- actual private type whose full view is not in scope.
7672 elsif Ekind (Type_2) = E_Private_Subtype
7673 and then In_Instance
7674 and then Etype (Type_2) = Type_1
7678 -- In Ada 2012, incomplete types (including limited views) can appear
7679 -- as actuals in instantiations, where they are conformant to the
7680 -- corresponding incomplete formal.
7682 elsif Is_Incomplete_Type (Type_1)
7683 and then Is_Incomplete_Type (Type_2)
7684 and then In_Instance
7685 and then (Used_As_Generic_Actual (Type_1)
7686 or else Used_As_Generic_Actual (Type_2))
7691 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7692 -- treated recursively because they carry a signature. As far as
7693 -- conformance is concerned, convention plays no role, and either
7694 -- or both could be access to protected subprograms.
7696 Are_Anonymous_Access_To_Subprogram_Types :=
7697 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7698 E_Anonymous_Access_Protected_Subprogram_Type)
7700 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7701 E_Anonymous_Access_Protected_Subprogram_Type);
7703 -- Test anonymous access type case. For this case, static subtype
7704 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7705 -- the base types because we may have built internal subtype entities
7706 -- to handle null-excluding types (see Process_Formals).
7708 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7710 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7712 -- Ada 2005 (AI-254)
7714 or else Are_Anonymous_Access_To_Subprogram_Types
7717 Desig_1 : Entity_Id;
7718 Desig_2 : Entity_Id;
7721 -- In Ada 2005, access constant indicators must match for
7722 -- subtype conformance.
7724 if Ada_Version >= Ada_2005
7725 and then Ctype >= Subtype_Conformant
7727 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7732 Desig_1 := Find_Designated_Type (Type_1);
7733 Desig_2 := Find_Designated_Type (Type_2);
7735 -- If the context is an instance association for a formal
7736 -- access-to-subprogram type; formal access parameter designated
7737 -- types require mapping because they may denote other formal
7738 -- parameters of the generic unit.
7741 Desig_1 := Get_Instance_Of (Desig_1);
7742 Desig_2 := Get_Instance_Of (Desig_2);
7745 -- It is possible for a Class_Wide_Type to be introduced for an
7746 -- incomplete type, in which case there is a separate class_ wide
7747 -- type for the full view. The types conform if their Etypes
7748 -- conform, i.e. one may be the full view of the other. This can
7749 -- only happen in the context of an access parameter, other uses
7750 -- of an incomplete Class_Wide_Type are illegal.
7752 if Is_Class_Wide_Type (Desig_1)
7754 Is_Class_Wide_Type (Desig_2)
7758 (Etype (Base_Type (Desig_1)),
7759 Etype (Base_Type (Desig_2)), Ctype);
7761 elsif Are_Anonymous_Access_To_Subprogram_Types then
7762 if Ada_Version < Ada_2005 then
7764 Ctype = Type_Conformant
7765 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7767 -- We must check the conformance of the signatures themselves
7771 Conformant : Boolean;
7774 (Desig_1, Desig_2, Ctype, False, Conformant);
7779 -- A limited view of an actual matches the corresponding
7780 -- incomplete formal.
7782 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7783 and then From_Limited_With (Desig_2)
7784 and then Used_As_Generic_Actual (Etype (Desig_2))
7789 return Base_Type (Desig_1) = Base_Type (Desig_2)
7790 and then (Ctype = Type_Conformant
7792 Subtypes_Statically_Match (Desig_1, Desig_2));
7796 -- Otherwise definitely no match
7799 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7800 and then Is_Access_Type (Type_2))
7801 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7802 and then Is_Access_Type (Type_1)))
7805 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7807 May_Hide_Profile := True;
7812 end Conforming_Types;
7814 --------------------------
7815 -- Create_Extra_Formals --
7816 --------------------------
7818 procedure Create_Extra_Formals (E : Entity_Id) is
7819 First_Extra : Entity_Id := Empty;
7821 Last_Extra : Entity_Id := Empty;
7823 function Add_Extra_Formal
7824 (Assoc_Entity : Entity_Id;
7827 Suffix : String) return Entity_Id;
7828 -- Add an extra formal to the current list of formals and extra formals.
7829 -- The extra formal is added to the end of the list of extra formals,
7830 -- and also returned as the result. These formals are always of mode IN.
7831 -- The new formal has the type Typ, is declared in Scope, and its name
7832 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7833 -- The following suffixes are currently used. They should not be changed
7834 -- without coordinating with CodePeer, which makes use of these to
7835 -- provide better messages.
7837 -- O denotes the Constrained bit.
7838 -- L denotes the accessibility level.
7839 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7840 -- the full list in exp_ch6.BIP_Formal_Kind.
7842 ----------------------
7843 -- Add_Extra_Formal --
7844 ----------------------
7846 function Add_Extra_Formal
7847 (Assoc_Entity : Entity_Id;
7850 Suffix : String) return Entity_Id
7852 EF : constant Entity_Id :=
7853 Make_Defining_Identifier (Sloc (Assoc_Entity),
7854 Chars => New_External_Name (Chars (Assoc_Entity),
7858 -- A little optimization. Never generate an extra formal for the
7859 -- _init operand of an initialization procedure, since it could
7862 if Chars (Formal) = Name_uInit then
7866 Set_Ekind (EF, E_In_Parameter);
7867 Set_Actual_Subtype (EF, Typ);
7868 Set_Etype (EF, Typ);
7869 Set_Scope (EF, Scope);
7870 Set_Mechanism (EF, Default_Mechanism);
7871 Set_Formal_Validity (EF);
7873 if No (First_Extra) then
7875 Set_Extra_Formals (Scope, EF);
7878 if Present (Last_Extra) then
7879 Set_Extra_Formal (Last_Extra, EF);
7885 end Add_Extra_Formal;
7889 Formal_Type : Entity_Id;
7890 P_Formal : Entity_Id := Empty;
7892 -- Start of processing for Create_Extra_Formals
7895 -- We never generate extra formals if expansion is not active because we
7896 -- don't need them unless we are generating code.
7898 if not Expander_Active then
7902 -- No need to generate extra formals in interface thunks whose target
7903 -- primitive has no extra formals.
7905 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7909 -- If this is a derived subprogram then the subtypes of the parent
7910 -- subprogram's formal parameters will be used to determine the need
7911 -- for extra formals.
7913 if Is_Overloadable (E) and then Present (Alias (E)) then
7914 P_Formal := First_Formal (Alias (E));
7917 Formal := First_Formal (E);
7918 while Present (Formal) loop
7919 Last_Extra := Formal;
7920 Next_Formal (Formal);
7923 -- If Extra_Formals were already created, don't do it again. This
7924 -- situation may arise for subprogram types created as part of
7925 -- dispatching calls (see Expand_Dispatching_Call).
7927 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7931 -- If the subprogram is a predefined dispatching subprogram then don't
7932 -- generate any extra constrained or accessibility level formals. In
7933 -- general we suppress these for internal subprograms (by not calling
7934 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7935 -- generated stream attributes do get passed through because extra
7936 -- build-in-place formals are needed in some cases (limited 'Input).
7938 if Is_Predefined_Internal_Operation (E) then
7939 goto Test_For_Func_Result_Extras;
7942 Formal := First_Formal (E);
7943 while Present (Formal) loop
7945 -- Create extra formal for supporting the attribute 'Constrained.
7946 -- The case of a private type view without discriminants also
7947 -- requires the extra formal if the underlying type has defaulted
7950 if Ekind (Formal) /= E_In_Parameter then
7951 if Present (P_Formal) then
7952 Formal_Type := Etype (P_Formal);
7954 Formal_Type := Etype (Formal);
7957 -- Do not produce extra formals for Unchecked_Union parameters.
7958 -- Jump directly to the end of the loop.
7960 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7961 goto Skip_Extra_Formal_Generation;
7964 if not Has_Discriminants (Formal_Type)
7965 and then Ekind (Formal_Type) in Private_Kind
7966 and then Present (Underlying_Type (Formal_Type))
7968 Formal_Type := Underlying_Type (Formal_Type);
7971 -- Suppress the extra formal if formal's subtype is constrained or
7972 -- indefinite, or we're compiling for Ada 2012 and the underlying
7973 -- type is tagged and limited. In Ada 2012, a limited tagged type
7974 -- can have defaulted discriminants, but 'Constrained is required
7975 -- to return True, so the formal is never needed (see AI05-0214).
7976 -- Note that this ensures consistency of calling sequences for
7977 -- dispatching operations when some types in a class have defaults
7978 -- on discriminants and others do not (and requiring the extra
7979 -- formal would introduce distributed overhead).
7981 -- If the type does not have a completion yet, treat as prior to
7982 -- Ada 2012 for consistency.
7984 if Has_Discriminants (Formal_Type)
7985 and then not Is_Constrained (Formal_Type)
7986 and then Is_Definite_Subtype (Formal_Type)
7987 and then (Ada_Version < Ada_2012
7988 or else No (Underlying_Type (Formal_Type))
7990 (Is_Limited_Type (Formal_Type)
7993 (Underlying_Type (Formal_Type)))))
7995 Set_Extra_Constrained
7996 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8000 -- Create extra formal for supporting accessibility checking. This
8001 -- is done for both anonymous access formals and formals of named
8002 -- access types that are marked as controlling formals. The latter
8003 -- case can occur when Expand_Dispatching_Call creates a subprogram
8004 -- type and substitutes the types of access-to-class-wide actuals
8005 -- for the anonymous access-to-specific-type of controlling formals.
8006 -- Base_Type is applied because in cases where there is a null
8007 -- exclusion the formal may have an access subtype.
8009 -- This is suppressed if we specifically suppress accessibility
8010 -- checks at the package level for either the subprogram, or the
8011 -- package in which it resides. However, we do not suppress it
8012 -- simply if the scope has accessibility checks suppressed, since
8013 -- this could cause trouble when clients are compiled with a
8014 -- different suppression setting. The explicit checks at the
8015 -- package level are safe from this point of view.
8017 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8018 or else (Is_Controlling_Formal (Formal)
8019 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8021 (Explicit_Suppress (E, Accessibility_Check)
8023 Explicit_Suppress (Scope (E), Accessibility_Check))
8026 or else Present (Extra_Accessibility (P_Formal)))
8028 Set_Extra_Accessibility
8029 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8032 -- This label is required when skipping extra formal generation for
8033 -- Unchecked_Union parameters.
8035 <<Skip_Extra_Formal_Generation>>
8037 if Present (P_Formal) then
8038 Next_Formal (P_Formal);
8041 Next_Formal (Formal);
8044 <<Test_For_Func_Result_Extras>>
8046 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8047 -- function call is ... determined by the point of call ...".
8049 if Needs_Result_Accessibility_Level (E) then
8050 Set_Extra_Accessibility_Of_Result
8051 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8054 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8055 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8057 if Is_Build_In_Place_Function (E) then
8059 Result_Subt : constant Entity_Id := Etype (E);
8060 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8061 Formal_Typ : Entity_Id;
8062 Subp_Decl : Node_Id;
8063 Discard : Entity_Id;
8066 -- In the case of functions with unconstrained result subtypes,
8067 -- add a 4-state formal indicating whether the return object is
8068 -- allocated by the caller (1), or should be allocated by the
8069 -- callee on the secondary stack (2), in the global heap (3), or
8070 -- in a user-defined storage pool (4). For the moment we just use
8071 -- Natural for the type of this formal. Note that this formal
8072 -- isn't usually needed in the case where the result subtype is
8073 -- constrained, but it is needed when the function has a tagged
8074 -- result, because generally such functions can be called in a
8075 -- dispatching context and such calls must be handled like calls
8076 -- to a class-wide function.
8078 if Needs_BIP_Alloc_Form (E) then
8081 (E, Standard_Natural,
8082 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8084 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8085 -- use a user-defined pool. This formal is not added on
8086 -- ZFP as those targets do not support pools.
8088 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8091 (E, RTE (RE_Root_Storage_Pool_Ptr),
8092 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8096 -- In the case of functions whose result type needs finalization,
8097 -- add an extra formal which represents the finalization master.
8099 if Needs_BIP_Finalization_Master (E) then
8102 (E, RTE (RE_Finalization_Master_Ptr),
8103 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8106 -- When the result type contains tasks, add two extra formals: the
8107 -- master of the tasks to be created, and the caller's activation
8110 if Has_Task (Full_Subt) then
8113 (E, RTE (RE_Master_Id),
8114 E, BIP_Formal_Suffix (BIP_Task_Master));
8117 (E, RTE (RE_Activation_Chain_Access),
8118 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8121 -- All build-in-place functions get an extra formal that will be
8122 -- passed the address of the return object within the caller.
8125 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8127 -- Incomplete_View_From_Limited_With is needed here because
8128 -- gigi gets confused if the designated type is the full view
8129 -- coming from a limited-with'ed package. In the normal case,
8130 -- (no limited with) Incomplete_View_From_Limited_With
8131 -- returns Result_Subt.
8133 Set_Directly_Designated_Type
8134 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8135 Set_Etype (Formal_Typ, Formal_Typ);
8136 Set_Depends_On_Private
8137 (Formal_Typ, Has_Private_Component (Formal_Typ));
8138 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8139 Set_Is_Access_Constant (Formal_Typ, False);
8141 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8142 -- the designated type comes from the limited view (for back-end
8145 Set_From_Limited_With
8146 (Formal_Typ, From_Limited_With (Result_Subt));
8148 Layout_Type (Formal_Typ);
8150 -- Force the definition of the Itype in case of internal function
8151 -- calls within the same or nested scope.
8153 if Is_Subprogram_Or_Generic_Subprogram (E) then
8154 Subp_Decl := Parent (E);
8156 -- The insertion point for an Itype reference should be after
8157 -- the unit declaration node of the subprogram. An exception
8158 -- to this are inherited operations from a parent type in which
8159 -- case the derived type acts as their parent.
8161 if Nkind_In (Subp_Decl, N_Function_Specification,
8162 N_Procedure_Specification)
8164 Subp_Decl := Parent (Subp_Decl);
8167 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8172 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8176 -- If this is an instance of a generic, we need to have extra formals
8179 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8180 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8182 end Create_Extra_Formals;
8184 -----------------------------
8185 -- Enter_Overloaded_Entity --
8186 -----------------------------
8188 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8189 function Matches_Predefined_Op return Boolean;
8190 -- This returns an approximation of whether S matches a predefined
8191 -- operator, based on the operator symbol, and the parameter and result
8192 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8194 ---------------------------
8195 -- Matches_Predefined_Op --
8196 ---------------------------
8198 function Matches_Predefined_Op return Boolean is
8199 Formal_1 : constant Entity_Id := First_Formal (S);
8200 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8201 Op : constant Name_Id := Chars (S);
8202 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8203 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8208 if Present (Formal_2) then
8210 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8213 -- All but "&" and "**" have same-types parameters
8222 if Type_1 /= Type_2 then
8227 -- Check parameter and result types
8235 Is_Boolean_Type (Result_Type)
8236 and then Result_Type = Type_1;
8242 Is_Integer_Type (Result_Type)
8243 and then Result_Type = Type_1;
8251 Is_Numeric_Type (Result_Type)
8252 and then Result_Type = Type_1;
8258 Is_Boolean_Type (Result_Type)
8259 and then not Is_Limited_Type (Type_1);
8267 Is_Boolean_Type (Result_Type)
8268 and then (Is_Array_Type (Type_1)
8269 or else Is_Scalar_Type (Type_1));
8271 when Name_Op_Concat =>
8272 return Is_Array_Type (Result_Type);
8274 when Name_Op_Expon =>
8276 (Is_Integer_Type (Result_Type)
8277 or else Is_Floating_Point_Type (Result_Type))
8278 and then Result_Type = Type_1
8279 and then Type_2 = Standard_Integer;
8282 raise Program_Error;
8295 Is_Numeric_Type (Result_Type)
8296 and then Result_Type = Type_1;
8300 Is_Boolean_Type (Result_Type)
8301 and then Result_Type = Type_1;
8304 raise Program_Error;
8307 end Matches_Predefined_Op;
8311 E : Entity_Id := Current_Entity_In_Scope (S);
8312 C_E : Entity_Id := Current_Entity (S);
8314 -- Start of processing for Enter_Overloaded_Entity
8318 Set_Has_Homonym (E);
8319 Set_Has_Homonym (S);
8322 Set_Is_Immediately_Visible (S);
8323 Set_Scope (S, Current_Scope);
8325 -- Chain new entity if front of homonym in current scope, so that
8326 -- homonyms are contiguous.
8328 if Present (E) and then E /= C_E then
8329 while Homonym (C_E) /= E loop
8330 C_E := Homonym (C_E);
8333 Set_Homonym (C_E, S);
8337 Set_Current_Entity (S);
8342 if Is_Inherited_Operation (S) then
8343 Append_Inherited_Subprogram (S);
8345 Append_Entity (S, Current_Scope);
8348 Set_Public_Status (S);
8350 if Debug_Flag_E then
8351 Write_Str ("New overloaded entity chain: ");
8352 Write_Name (Chars (S));
8355 while Present (E) loop
8356 Write_Str (" "); Write_Int (Int (E));
8363 -- Generate warning for hiding
8366 and then Comes_From_Source (S)
8367 and then In_Extended_Main_Source_Unit (S)
8374 -- Warn unless genuine overloading. Do not emit warning on
8375 -- hiding predefined operators in Standard (these are either an
8376 -- (artifact of our implicit declarations, or simple noise) but
8377 -- keep warning on a operator defined on a local subtype, because
8378 -- of the real danger that different operators may be applied in
8379 -- various parts of the program.
8381 -- Note that if E and S have the same scope, there is never any
8382 -- hiding. Either the two conflict, and the program is illegal,
8383 -- or S is overriding an implicit inherited subprogram.
8385 if Scope (E) /= Scope (S)
8386 and then (not Is_Overloadable (E)
8387 or else Subtype_Conformant (E, S))
8388 and then (Is_Immediately_Visible (E)
8389 or else Is_Potentially_Use_Visible (S))
8391 if Scope (E) = Standard_Standard then
8392 if Nkind (S) = N_Defining_Operator_Symbol
8393 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8395 and then Matches_Predefined_Op
8398 ("declaration of & hides predefined operator?h?", S);
8401 -- E not immediately within Standard
8404 Error_Msg_Sloc := Sloc (E);
8405 Error_Msg_N ("declaration of & hides one #?h?", S);
8410 end Enter_Overloaded_Entity;
8412 -----------------------------
8413 -- Check_Untagged_Equality --
8414 -----------------------------
8416 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8417 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8418 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8422 -- This check applies only if we have a subprogram declaration with an
8423 -- untagged record type.
8425 if Nkind (Decl) /= N_Subprogram_Declaration
8426 or else not Is_Record_Type (Typ)
8427 or else Is_Tagged_Type (Typ)
8432 -- In Ada 2012 case, we will output errors or warnings depending on
8433 -- the setting of debug flag -gnatd.E.
8435 if Ada_Version >= Ada_2012 then
8436 Error_Msg_Warn := Debug_Flag_Dot_EE;
8438 -- In earlier versions of Ada, nothing to do unless we are warning on
8439 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8442 if not Warn_On_Ada_2012_Compatibility then
8447 -- Cases where the type has already been frozen
8449 if Is_Frozen (Typ) then
8451 -- The check applies to a primitive operation, so check that type
8452 -- and equality operation are in the same scope.
8454 if Scope (Typ) /= Current_Scope then
8457 -- If the type is a generic actual (sub)type, the operation is not
8458 -- primitive either because the base type is declared elsewhere.
8460 elsif Is_Generic_Actual_Type (Typ) then
8463 -- Here we have a definite error of declaration after freezing
8466 if Ada_Version >= Ada_2012 then
8468 ("equality operator must be declared before type & is "
8469 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8471 -- In Ada 2012 mode with error turned to warning, output one
8472 -- more warning to warn that the equality operation may not
8473 -- compose. This is the consequence of ignoring the error.
8475 if Error_Msg_Warn then
8476 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8481 ("equality operator must be declared before type& is "
8482 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8485 -- If we are in the package body, we could just move the
8486 -- declaration to the package spec, so add a message saying that.
8488 if In_Package_Body (Scope (Typ)) then
8489 if Ada_Version >= Ada_2012 then
8491 ("\move declaration to package spec<<", Eq_Op);
8494 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8497 -- Otherwise try to find the freezing point for better message.
8500 Obj_Decl := Next (Parent (Typ));
8501 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8502 if Nkind (Obj_Decl) = N_Object_Declaration
8503 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8505 -- Freezing point, output warnings
8507 if Ada_Version >= Ada_2012 then
8509 ("type& is frozen by declaration??", Obj_Decl, Typ);
8511 ("\an equality operator cannot be declared after "
8516 ("type& is frozen by declaration (Ada 2012)?y?",
8519 ("\an equality operator cannot be declared after "
8520 & "this point (Ada 2012)?y?",
8526 -- If we reach generated code for subprogram declaration
8527 -- or body, it is the body that froze the type and the
8528 -- declaration is legal.
8530 elsif Sloc (Obj_Decl) = Sloc (Decl) then
8539 -- Here if type is not frozen yet. It is illegal to have a primitive
8540 -- equality declared in the private part if the type is visible.
8542 elsif not In_Same_List (Parent (Typ), Decl)
8543 and then not Is_Limited_Type (Typ)
8545 -- Shouldn't we give an RM reference here???
8547 if Ada_Version >= Ada_2012 then
8549 ("equality operator appears too late<<", Eq_Op);
8552 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8555 -- No error detected
8560 end Check_Untagged_Equality;
8562 -----------------------------
8563 -- Find_Corresponding_Spec --
8564 -----------------------------
8566 function Find_Corresponding_Spec
8568 Post_Error : Boolean := True) return Entity_Id
8570 Spec : constant Node_Id := Specification (N);
8571 Designator : constant Entity_Id := Defining_Entity (Spec);
8575 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8576 -- Even if fully conformant, a body may depend on a generic actual when
8577 -- the spec does not, or vice versa, in which case they were distinct
8578 -- entities in the generic.
8580 -------------------------------
8581 -- Different_Generic_Profile --
8582 -------------------------------
8584 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8587 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8588 -- Check that the types of corresponding formals have the same
8589 -- generic actual if any. We have to account for subtypes of a
8590 -- generic formal, declared between a spec and a body, which may
8591 -- appear distinct in an instance but matched in the generic, and
8592 -- the subtype may be used either in the spec or the body of the
8593 -- subprogram being checked.
8595 -------------------------
8596 -- Same_Generic_Actual --
8597 -------------------------
8599 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8601 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8602 -- Predicate to check whether S1 is a subtype of S2 in the source
8605 -------------------------
8606 -- Is_Declared_Subtype --
8607 -------------------------
8609 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8611 return Comes_From_Source (Parent (S1))
8612 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8613 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8614 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8615 end Is_Declared_Subtype;
8617 -- Start of processing for Same_Generic_Actual
8620 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8621 or else Is_Declared_Subtype (T1, T2)
8622 or else Is_Declared_Subtype (T2, T1);
8623 end Same_Generic_Actual;
8625 -- Start of processing for Different_Generic_Profile
8628 if not In_Instance then
8631 elsif Ekind (E) = E_Function
8632 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8637 F1 := First_Formal (Designator);
8638 F2 := First_Formal (E);
8639 while Present (F1) loop
8640 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8649 end Different_Generic_Profile;
8651 -- Start of processing for Find_Corresponding_Spec
8654 E := Current_Entity (Designator);
8655 while Present (E) loop
8657 -- We are looking for a matching spec. It must have the same scope,
8658 -- and the same name, and either be type conformant, or be the case
8659 -- of a library procedure spec and its body (which belong to one
8660 -- another regardless of whether they are type conformant or not).
8662 if Scope (E) = Current_Scope then
8663 if Current_Scope = Standard_Standard
8664 or else (Ekind (E) = Ekind (Designator)
8665 and then Type_Conformant (E, Designator))
8667 -- Within an instantiation, we know that spec and body are
8668 -- subtype conformant, because they were subtype conformant in
8669 -- the generic. We choose the subtype-conformant entity here as
8670 -- well, to resolve spurious ambiguities in the instance that
8671 -- were not present in the generic (i.e. when two different
8672 -- types are given the same actual). If we are looking for a
8673 -- spec to match a body, full conformance is expected.
8677 -- Inherit the convention and "ghostness" of the matching
8678 -- spec to ensure proper full and subtype conformance.
8680 Set_Convention (Designator, Convention (E));
8682 -- Skip past subprogram bodies and subprogram renamings that
8683 -- may appear to have a matching spec, but that aren't fully
8684 -- conformant with it. That can occur in cases where an
8685 -- actual type causes unrelated homographs in the instance.
8687 if Nkind_In (N, N_Subprogram_Body,
8688 N_Subprogram_Renaming_Declaration)
8689 and then Present (Homonym (E))
8690 and then not Fully_Conformant (Designator, E)
8694 elsif not Subtype_Conformant (Designator, E) then
8697 elsif Different_Generic_Profile (E) then
8702 -- Ada 2012 (AI05-0165): For internally generated bodies of
8703 -- null procedures locate the internally generated spec. We
8704 -- enforce mode conformance since a tagged type may inherit
8705 -- from interfaces several null primitives which differ only
8706 -- in the mode of the formals.
8708 if not (Comes_From_Source (E))
8709 and then Is_Null_Procedure (E)
8710 and then not Mode_Conformant (Designator, E)
8714 -- For null procedures coming from source that are completions,
8715 -- analysis of the generated body will establish the link.
8717 elsif Comes_From_Source (E)
8718 and then Nkind (Spec) = N_Procedure_Specification
8719 and then Null_Present (Spec)
8723 -- Expression functions can be completions, but cannot be
8724 -- completed by an explicit body.
8726 elsif Comes_From_Source (E)
8727 and then Comes_From_Source (N)
8728 and then Nkind (N) = N_Subprogram_Body
8729 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8730 N_Expression_Function
8732 Error_Msg_Sloc := Sloc (E);
8733 Error_Msg_N ("body conflicts with expression function#", N);
8736 elsif not Has_Completion (E) then
8737 if Nkind (N) /= N_Subprogram_Body_Stub then
8738 Set_Corresponding_Spec (N, E);
8741 Set_Has_Completion (E);
8744 elsif Nkind (Parent (N)) = N_Subunit then
8746 -- If this is the proper body of a subunit, the completion
8747 -- flag is set when analyzing the stub.
8751 -- If E is an internal function with a controlling result that
8752 -- was created for an operation inherited by a null extension,
8753 -- it may be overridden by a body without a previous spec (one
8754 -- more reason why these should be shunned). In that case we
8755 -- remove the generated body if present, because the current
8756 -- one is the explicit overriding.
8758 elsif Ekind (E) = E_Function
8759 and then Ada_Version >= Ada_2005
8760 and then not Comes_From_Source (E)
8761 and then Has_Controlling_Result (E)
8762 and then Is_Null_Extension (Etype (E))
8763 and then Comes_From_Source (Spec)
8765 Set_Has_Completion (E, False);
8768 and then Nkind (Parent (E)) = N_Function_Specification
8771 (Unit_Declaration_Node
8772 (Corresponding_Body (Unit_Declaration_Node (E))));
8776 -- If expansion is disabled, or if the wrapper function has
8777 -- not been generated yet, this a late body overriding an
8778 -- inherited operation, or it is an overriding by some other
8779 -- declaration before the controlling result is frozen. In
8780 -- either case this is a declaration of a new entity.
8786 -- If the body already exists, then this is an error unless
8787 -- the previous declaration is the implicit declaration of a
8788 -- derived subprogram. It is also legal for an instance to
8789 -- contain type conformant overloadable declarations (but the
8790 -- generic declaration may not), per 8.3(26/2).
8792 elsif No (Alias (E))
8793 and then not Is_Intrinsic_Subprogram (E)
8794 and then not In_Instance
8797 Error_Msg_Sloc := Sloc (E);
8799 if Is_Imported (E) then
8801 ("body not allowed for imported subprogram & declared#",
8804 Error_Msg_NE ("duplicate body for & declared#", N, E);
8808 -- Child units cannot be overloaded, so a conformance mismatch
8809 -- between body and a previous spec is an error.
8811 elsif Is_Child_Unit (E)
8813 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8815 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8820 ("body of child unit does not match previous declaration", N);
8828 -- On exit, we know that no previous declaration of subprogram exists
8831 end Find_Corresponding_Spec;
8833 ----------------------
8834 -- Fully_Conformant --
8835 ----------------------
8837 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8840 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8842 end Fully_Conformant;
8844 ----------------------------------
8845 -- Fully_Conformant_Expressions --
8846 ----------------------------------
8848 function Fully_Conformant_Expressions
8849 (Given_E1 : Node_Id;
8851 Report : Boolean := False) return Boolean
8853 E1 : constant Node_Id := Original_Node (Given_E1);
8854 E2 : constant Node_Id := Original_Node (Given_E2);
8855 -- We always test conformance on original nodes, since it is possible
8856 -- for analysis and/or expansion to make things look as though they
8857 -- conform when they do not, e.g. by converting 1+2 into 3.
8859 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean;
8862 function FCL (L1 : List_Id; L2 : List_Id) return Boolean;
8863 -- Compare elements of two lists for conformance. Elements have to be
8864 -- conformant, and actuals inserted as default parameters do not match
8865 -- explicit actuals with the same value.
8867 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean;
8868 -- Compare an operator node with a function call
8874 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean is
8876 return Fully_Conformant_Expressions (Given_E1, Given_E2, Report);
8883 function FCL (L1 : List_Id; L2 : List_Id) return Boolean is
8888 if L1 = No_List then
8894 if L2 = No_List then
8900 -- Compare two lists, skipping rewrite insertions (we want to compare
8901 -- the original trees, not the expanded versions).
8904 if Is_Rewrite_Insertion (N1) then
8906 elsif Is_Rewrite_Insertion (N2) then
8912 elsif not FCE (N1, N2) then
8925 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean is
8926 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8931 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8936 Act := First (Actuals);
8938 if Nkind (Op_Node) in N_Binary_Op then
8939 if not FCE (Left_Opnd (Op_Node), Act) then
8946 return Present (Act)
8947 and then FCE (Right_Opnd (Op_Node), Act)
8948 and then No (Next (Act));
8956 -- Start of processing for Fully_Conformant_Expressions
8961 -- Nonconformant if paren count does not match. Note: if some idiot
8962 -- complains that we don't do this right for more than 3 levels of
8963 -- parentheses, they will be treated with the respect they deserve.
8965 if Paren_Count (E1) /= Paren_Count (E2) then
8968 -- If same entities are referenced, then they are conformant even if
8969 -- they have different forms (RM 8.3.1(19-20)).
8971 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8972 if Present (Entity (E1)) then
8973 Result := Entity (E1) = Entity (E2)
8975 -- One may be a discriminant that has been replaced by the
8976 -- corresponding discriminal.
8979 (Chars (Entity (E1)) = Chars (Entity (E2))
8980 and then Ekind (Entity (E1)) = E_Discriminant
8981 and then Ekind (Entity (E2)) = E_In_Parameter)
8983 -- The discriminant of a protected type is transformed into
8984 -- a local constant and then into a parameter of a protected
8988 (Ekind (Entity (E1)) = E_Constant
8989 and then Ekind (Entity (E2)) = E_In_Parameter
8990 and then Present (Discriminal_Link (Entity (E1)))
8991 and then Discriminal_Link (Entity (E1)) =
8992 Discriminal_Link (Entity (E2)))
8994 -- AI12-050: The loop variables of quantified expressions match
8995 -- if they have the same identifier, even though they may have
8996 -- different entities.
8999 (Chars (Entity (E1)) = Chars (Entity (E2))
9000 and then Ekind (Entity (E1)) = E_Loop_Parameter
9001 and then Ekind (Entity (E2)) = E_Loop_Parameter)
9003 -- A call to an instantiation of Unchecked_Conversion is
9004 -- rewritten with the name of the generated function created for
9005 -- the instance, and this must be special-cased.
9008 (Ekind (Entity (E1)) = E_Function
9009 and then Is_Intrinsic_Subprogram (Entity (E1))
9010 and then Is_Generic_Instance (Entity (E1))
9011 and then Entity (E2) = Alias (Entity (E1)));
9012 if Report and not Result then
9014 Text_Ptr'Max (Sloc (Entity (E1)), Sloc (Entity (E2)));
9016 ("Meaning of& differs because of declaration#", E1, E2);
9021 elsif Nkind (E1) = N_Expanded_Name
9022 and then Nkind (E2) = N_Expanded_Name
9023 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9024 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9026 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9029 -- Identifiers in component associations don't always have
9030 -- entities, but their names must conform.
9032 return Nkind (E1) = N_Identifier
9033 and then Nkind (E2) = N_Identifier
9034 and then Chars (E1) = Chars (E2);
9037 elsif Nkind (E1) = N_Character_Literal
9038 and then Nkind (E2) = N_Expanded_Name
9040 return Nkind (Selector_Name (E2)) = N_Character_Literal
9041 and then Chars (E1) = Chars (Selector_Name (E2));
9043 elsif Nkind (E2) = N_Character_Literal
9044 and then Nkind (E1) = N_Expanded_Name
9046 return Nkind (Selector_Name (E1)) = N_Character_Literal
9047 and then Chars (E2) = Chars (Selector_Name (E1));
9049 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9050 return FCO (E1, E2);
9052 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9053 return FCO (E2, E1);
9055 -- Otherwise we must have the same syntactic entity
9057 elsif Nkind (E1) /= Nkind (E2) then
9060 -- At this point, we specialize by node type
9066 FCL (Expressions (E1), Expressions (E2))
9068 FCL (Component_Associations (E1),
9069 Component_Associations (E2));
9072 if Nkind (Expression (E1)) = N_Qualified_Expression
9074 Nkind (Expression (E2)) = N_Qualified_Expression
9076 return FCE (Expression (E1), Expression (E2));
9078 -- Check that the subtype marks and any constraints
9083 Indic1 : constant Node_Id := Expression (E1);
9084 Indic2 : constant Node_Id := Expression (E2);
9089 if Nkind (Indic1) /= N_Subtype_Indication then
9091 Nkind (Indic2) /= N_Subtype_Indication
9092 and then Entity (Indic1) = Entity (Indic2);
9094 elsif Nkind (Indic2) /= N_Subtype_Indication then
9096 Nkind (Indic1) /= N_Subtype_Indication
9097 and then Entity (Indic1) = Entity (Indic2);
9100 if Entity (Subtype_Mark (Indic1)) /=
9101 Entity (Subtype_Mark (Indic2))
9106 Elt1 := First (Constraints (Constraint (Indic1)));
9107 Elt2 := First (Constraints (Constraint (Indic2)));
9108 while Present (Elt1) and then Present (Elt2) loop
9109 if not FCE (Elt1, Elt2) then
9122 when N_Attribute_Reference =>
9124 Attribute_Name (E1) = Attribute_Name (E2)
9125 and then FCL (Expressions (E1), Expressions (E2));
9129 Entity (E1) = Entity (E2)
9130 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9131 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9133 when N_Membership_Test
9137 FCE (Left_Opnd (E1), Left_Opnd (E2))
9139 FCE (Right_Opnd (E1), Right_Opnd (E2));
9141 when N_Case_Expression =>
9147 if not FCE (Expression (E1), Expression (E2)) then
9151 Alt1 := First (Alternatives (E1));
9152 Alt2 := First (Alternatives (E2));
9154 if Present (Alt1) /= Present (Alt2) then
9156 elsif No (Alt1) then
9160 if not FCE (Expression (Alt1), Expression (Alt2))
9161 or else not FCL (Discrete_Choices (Alt1),
9162 Discrete_Choices (Alt2))
9173 when N_Character_Literal =>
9175 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9177 when N_Component_Association =>
9179 FCL (Choices (E1), Choices (E2))
9181 FCE (Expression (E1), Expression (E2));
9183 when N_Explicit_Dereference =>
9185 FCE (Prefix (E1), Prefix (E2));
9187 when N_Extension_Aggregate =>
9189 FCL (Expressions (E1), Expressions (E2))
9190 and then Null_Record_Present (E1) =
9191 Null_Record_Present (E2)
9192 and then FCL (Component_Associations (E1),
9193 Component_Associations (E2));
9195 when N_Function_Call =>
9197 FCE (Name (E1), Name (E2))
9199 FCL (Parameter_Associations (E1),
9200 Parameter_Associations (E2));
9202 when N_If_Expression =>
9204 FCL (Expressions (E1), Expressions (E2));
9206 when N_Indexed_Component =>
9208 FCE (Prefix (E1), Prefix (E2))
9210 FCL (Expressions (E1), Expressions (E2));
9212 when N_Integer_Literal =>
9213 return (Intval (E1) = Intval (E2));
9218 when N_Operator_Symbol =>
9220 Chars (E1) = Chars (E2);
9222 when N_Others_Choice =>
9225 when N_Parameter_Association =>
9227 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9228 and then FCE (Explicit_Actual_Parameter (E1),
9229 Explicit_Actual_Parameter (E2));
9231 when N_Qualified_Expression
9233 | N_Unchecked_Type_Conversion
9236 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9238 FCE (Expression (E1), Expression (E2));
9240 when N_Quantified_Expression =>
9241 if not FCE (Condition (E1), Condition (E2)) then
9245 if Present (Loop_Parameter_Specification (E1))
9246 and then Present (Loop_Parameter_Specification (E2))
9249 L1 : constant Node_Id :=
9250 Loop_Parameter_Specification (E1);
9251 L2 : constant Node_Id :=
9252 Loop_Parameter_Specification (E2);
9256 Reverse_Present (L1) = Reverse_Present (L2)
9258 FCE (Defining_Identifier (L1),
9259 Defining_Identifier (L2))
9261 FCE (Discrete_Subtype_Definition (L1),
9262 Discrete_Subtype_Definition (L2));
9265 elsif Present (Iterator_Specification (E1))
9266 and then Present (Iterator_Specification (E2))
9269 I1 : constant Node_Id := Iterator_Specification (E1);
9270 I2 : constant Node_Id := Iterator_Specification (E2);
9274 FCE (Defining_Identifier (I1),
9275 Defining_Identifier (I2))
9277 Of_Present (I1) = Of_Present (I2)
9279 Reverse_Present (I1) = Reverse_Present (I2)
9280 and then FCE (Name (I1), Name (I2))
9281 and then FCE (Subtype_Indication (I1),
9282 Subtype_Indication (I2));
9285 -- The quantified expressions used different specifications to
9286 -- walk their respective ranges.
9294 FCE (Low_Bound (E1), Low_Bound (E2))
9296 FCE (High_Bound (E1), High_Bound (E2));
9298 when N_Real_Literal =>
9299 return (Realval (E1) = Realval (E2));
9301 when N_Selected_Component =>
9303 FCE (Prefix (E1), Prefix (E2))
9305 FCE (Selector_Name (E1), Selector_Name (E2));
9309 FCE (Prefix (E1), Prefix (E2))
9311 FCE (Discrete_Range (E1), Discrete_Range (E2));
9313 when N_String_Literal =>
9315 S1 : constant String_Id := Strval (E1);
9316 S2 : constant String_Id := Strval (E2);
9317 L1 : constant Nat := String_Length (S1);
9318 L2 : constant Nat := String_Length (S2);
9325 for J in 1 .. L1 loop
9326 if Get_String_Char (S1, J) /=
9327 Get_String_Char (S2, J)
9339 Entity (E1) = Entity (E2)
9341 FCE (Right_Opnd (E1), Right_Opnd (E2));
9343 -- All other node types cannot appear in this context. Strictly
9344 -- we should raise a fatal internal error. Instead we just ignore
9345 -- the nodes. This means that if anyone makes a mistake in the
9346 -- expander and mucks an expression tree irretrievably, the result
9347 -- will be a failure to detect a (probably very obscure) case
9348 -- of non-conformance, which is better than bombing on some
9349 -- case where two expressions do in fact conform.
9355 end Fully_Conformant_Expressions;
9357 ----------------------------------------
9358 -- Fully_Conformant_Discrete_Subtypes --
9359 ----------------------------------------
9361 function Fully_Conformant_Discrete_Subtypes
9362 (Given_S1 : Node_Id;
9363 Given_S2 : Node_Id) return Boolean
9365 S1 : constant Node_Id := Original_Node (Given_S1);
9366 S2 : constant Node_Id := Original_Node (Given_S2);
9368 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9369 -- Special-case for a bound given by a discriminant, which in the body
9370 -- is replaced with the discriminal of the enclosing type.
9372 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9373 -- Check both bounds
9375 -----------------------
9376 -- Conforming_Bounds --
9377 -----------------------
9379 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9381 if Is_Entity_Name (B1)
9382 and then Is_Entity_Name (B2)
9383 and then Ekind (Entity (B1)) = E_Discriminant
9385 return Chars (B1) = Chars (B2);
9388 return Fully_Conformant_Expressions (B1, B2);
9390 end Conforming_Bounds;
9392 -----------------------
9393 -- Conforming_Ranges --
9394 -----------------------
9396 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9399 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9401 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9402 end Conforming_Ranges;
9404 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9407 if Nkind (S1) /= Nkind (S2) then
9410 elsif Is_Entity_Name (S1) then
9411 return Entity (S1) = Entity (S2);
9413 elsif Nkind (S1) = N_Range then
9414 return Conforming_Ranges (S1, S2);
9416 elsif Nkind (S1) = N_Subtype_Indication then
9418 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9421 (Range_Expression (Constraint (S1)),
9422 Range_Expression (Constraint (S2)));
9426 end Fully_Conformant_Discrete_Subtypes;
9428 --------------------
9429 -- Install_Entity --
9430 --------------------
9432 procedure Install_Entity (E : Entity_Id) is
9433 Prev : constant Entity_Id := Current_Entity (E);
9435 Set_Is_Immediately_Visible (E);
9436 Set_Current_Entity (E);
9437 Set_Homonym (E, Prev);
9440 ---------------------
9441 -- Install_Formals --
9442 ---------------------
9444 procedure Install_Formals (Id : Entity_Id) is
9447 F := First_Formal (Id);
9448 while Present (F) loop
9452 end Install_Formals;
9454 -----------------------------
9455 -- Is_Interface_Conformant --
9456 -----------------------------
9458 function Is_Interface_Conformant
9459 (Tagged_Type : Entity_Id;
9460 Iface_Prim : Entity_Id;
9461 Prim : Entity_Id) return Boolean
9463 -- The operation may in fact be an inherited (implicit) operation
9464 -- rather than the original interface primitive, so retrieve the
9465 -- ultimate ancestor.
9467 Iface : constant Entity_Id :=
9468 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9469 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9471 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9472 -- Return the controlling formal of Prim
9474 ------------------------
9475 -- Controlling_Formal --
9476 ------------------------
9478 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9482 E := First_Entity (Prim);
9483 while Present (E) loop
9484 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9492 end Controlling_Formal;
9496 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9497 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9499 -- Start of processing for Is_Interface_Conformant
9502 pragma Assert (Is_Subprogram (Iface_Prim)
9503 and then Is_Subprogram (Prim)
9504 and then Is_Dispatching_Operation (Iface_Prim)
9505 and then Is_Dispatching_Operation (Prim));
9507 pragma Assert (Is_Interface (Iface)
9508 or else (Present (Alias (Iface_Prim))
9511 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9513 if Prim = Iface_Prim
9514 or else not Is_Subprogram (Prim)
9515 or else Ekind (Prim) /= Ekind (Iface_Prim)
9516 or else not Is_Dispatching_Operation (Prim)
9517 or else Scope (Prim) /= Scope (Tagged_Type)
9519 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9520 or else not Primitive_Names_Match (Iface_Prim, Prim)
9524 -- The mode of the controlling formals must match
9526 elsif Present (Iface_Ctrl_F)
9527 and then Present (Prim_Ctrl_F)
9528 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9532 -- Case of a procedure, or a function whose result type matches the
9533 -- result type of the interface primitive, or a function that has no
9534 -- controlling result (I or access I).
9536 elsif Ekind (Iface_Prim) = E_Procedure
9537 or else Etype (Prim) = Etype (Iface_Prim)
9538 or else not Has_Controlling_Result (Prim)
9540 return Type_Conformant
9541 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9543 -- Case of a function returning an interface, or an access to one. Check
9544 -- that the return types correspond.
9546 elsif Implements_Interface (Typ, Iface) then
9547 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9549 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9554 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9555 Skip_Controlling_Formals => True);
9561 end Is_Interface_Conformant;
9563 ---------------------------------
9564 -- Is_Non_Overriding_Operation --
9565 ---------------------------------
9567 function Is_Non_Overriding_Operation
9568 (Prev_E : Entity_Id;
9569 New_E : Entity_Id) return Boolean
9573 G_Typ : Entity_Id := Empty;
9575 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9576 -- If F_Type is a derived type associated with a generic actual subtype,
9577 -- then return its Generic_Parent_Type attribute, else return Empty.
9579 function Types_Correspond
9580 (P_Type : Entity_Id;
9581 N_Type : Entity_Id) return Boolean;
9582 -- Returns true if and only if the types (or designated types in the
9583 -- case of anonymous access types) are the same or N_Type is derived
9584 -- directly or indirectly from P_Type.
9586 -----------------------------
9587 -- Get_Generic_Parent_Type --
9588 -----------------------------
9590 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9596 if Is_Derived_Type (F_Typ)
9597 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9599 -- The tree must be traversed to determine the parent subtype in
9600 -- the generic unit, which unfortunately isn't always available
9601 -- via semantic attributes. ??? (Note: The use of Original_Node
9602 -- is needed for cases where a full derived type has been
9605 -- If the parent type is a scalar type, the derivation creates
9606 -- an anonymous base type for it, and the source type is its
9609 if Is_Scalar_Type (F_Typ)
9610 and then not Comes_From_Source (F_Typ)
9614 (Original_Node (Parent (First_Subtype (F_Typ))));
9616 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9618 if Nkind (Defn) = N_Derived_Type_Definition then
9619 Indic := Subtype_Indication (Defn);
9621 if Nkind (Indic) = N_Subtype_Indication then
9622 G_Typ := Entity (Subtype_Mark (Indic));
9624 G_Typ := Entity (Indic);
9627 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9628 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9630 return Generic_Parent_Type (Parent (G_Typ));
9636 end Get_Generic_Parent_Type;
9638 ----------------------
9639 -- Types_Correspond --
9640 ----------------------
9642 function Types_Correspond
9643 (P_Type : Entity_Id;
9644 N_Type : Entity_Id) return Boolean
9646 Prev_Type : Entity_Id := Base_Type (P_Type);
9647 New_Type : Entity_Id := Base_Type (N_Type);
9650 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9651 Prev_Type := Designated_Type (Prev_Type);
9654 if Ekind (New_Type) = E_Anonymous_Access_Type then
9655 New_Type := Designated_Type (New_Type);
9658 if Prev_Type = New_Type then
9661 elsif not Is_Class_Wide_Type (New_Type) then
9662 while Etype (New_Type) /= New_Type loop
9663 New_Type := Etype (New_Type);
9665 if New_Type = Prev_Type then
9671 end Types_Correspond;
9673 -- Start of processing for Is_Non_Overriding_Operation
9676 -- In the case where both operations are implicit derived subprograms
9677 -- then neither overrides the other. This can only occur in certain
9678 -- obscure cases (e.g., derivation from homographs created in a generic
9681 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9684 elsif Ekind (Current_Scope) = E_Package
9685 and then Is_Generic_Instance (Current_Scope)
9686 and then In_Private_Part (Current_Scope)
9687 and then Comes_From_Source (New_E)
9689 -- We examine the formals and result type of the inherited operation,
9690 -- to determine whether their type is derived from (the instance of)
9691 -- a generic type. The first such formal or result type is the one
9694 Formal := First_Formal (Prev_E);
9696 while Present (Formal) loop
9697 F_Typ := Base_Type (Etype (Formal));
9699 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9700 F_Typ := Designated_Type (F_Typ);
9703 G_Typ := Get_Generic_Parent_Type (F_Typ);
9704 exit when Present (G_Typ);
9706 Next_Formal (Formal);
9709 -- If the function dispatches on result check the result type
9711 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9712 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9719 -- If the generic type is a private type, then the original operation
9720 -- was not overriding in the generic, because there was no primitive
9721 -- operation to override.
9723 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9724 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9725 N_Formal_Private_Type_Definition
9729 -- The generic parent type is the ancestor of a formal derived
9730 -- type declaration. We need to check whether it has a primitive
9731 -- operation that should be overridden by New_E in the generic.
9735 P_Formal : Entity_Id;
9736 N_Formal : Entity_Id;
9740 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9743 while Present (Prim_Elt) loop
9744 P_Prim := Node (Prim_Elt);
9746 if Chars (P_Prim) = Chars (New_E)
9747 and then Ekind (P_Prim) = Ekind (New_E)
9749 P_Formal := First_Formal (P_Prim);
9750 N_Formal := First_Formal (New_E);
9751 while Present (P_Formal) and then Present (N_Formal) loop
9752 P_Typ := Etype (P_Formal);
9753 N_Typ := Etype (N_Formal);
9755 if not Types_Correspond (P_Typ, N_Typ) then
9759 Next_Entity (P_Formal);
9760 Next_Entity (N_Formal);
9763 -- Found a matching primitive operation belonging to the
9764 -- formal ancestor type, so the new subprogram is
9768 and then No (N_Formal)
9769 and then (Ekind (New_E) /= E_Function
9772 (Etype (P_Prim), Etype (New_E)))
9778 Next_Elmt (Prim_Elt);
9781 -- If no match found, then the new subprogram does not override
9782 -- in the generic (nor in the instance).
9784 -- If the type in question is not abstract, and the subprogram
9785 -- is, this will be an error if the new operation is in the
9786 -- private part of the instance. Emit a warning now, which will
9787 -- make the subsequent error message easier to understand.
9789 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9790 and then Is_Abstract_Subprogram (Prev_E)
9791 and then In_Private_Part (Current_Scope)
9793 Error_Msg_Node_2 := F_Typ;
9795 ("private operation& in generic unit does not override "
9796 & "any primitive operation of& (RM 12.3 (18))??",
9806 end Is_Non_Overriding_Operation;
9808 -------------------------------------
9809 -- List_Inherited_Pre_Post_Aspects --
9810 -------------------------------------
9812 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9814 if Opt.List_Inherited_Aspects
9815 and then Is_Subprogram_Or_Generic_Subprogram (E)
9818 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9823 for Index in Subps'Range loop
9824 Items := Contract (Subps (Index));
9826 if Present (Items) then
9827 Prag := Pre_Post_Conditions (Items);
9828 while Present (Prag) loop
9829 Error_Msg_Sloc := Sloc (Prag);
9831 if Class_Present (Prag)
9832 and then not Split_PPC (Prag)
9834 if Pragma_Name (Prag) = Name_Precondition then
9836 ("info: & inherits `Pre''Class` aspect from "
9840 ("info: & inherits `Post''Class` aspect from "
9845 Prag := Next_Pragma (Prag);
9851 end List_Inherited_Pre_Post_Aspects;
9853 ------------------------------
9854 -- Make_Inequality_Operator --
9855 ------------------------------
9857 -- S is the defining identifier of an equality operator. We build a
9858 -- subprogram declaration with the right signature. This operation is
9859 -- intrinsic, because it is always expanded as the negation of the
9860 -- call to the equality function.
9862 procedure Make_Inequality_Operator (S : Entity_Id) is
9863 Loc : constant Source_Ptr := Sloc (S);
9866 Op_Name : Entity_Id;
9868 FF : constant Entity_Id := First_Formal (S);
9869 NF : constant Entity_Id := Next_Formal (FF);
9872 -- Check that equality was properly defined, ignore call if not
9879 A : constant Entity_Id :=
9880 Make_Defining_Identifier (Sloc (FF),
9881 Chars => Chars (FF));
9883 B : constant Entity_Id :=
9884 Make_Defining_Identifier (Sloc (NF),
9885 Chars => Chars (NF));
9888 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9890 Formals := New_List (
9891 Make_Parameter_Specification (Loc,
9892 Defining_Identifier => A,
9894 New_Occurrence_Of (Etype (First_Formal (S)),
9895 Sloc (Etype (First_Formal (S))))),
9897 Make_Parameter_Specification (Loc,
9898 Defining_Identifier => B,
9900 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9901 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9904 Make_Subprogram_Declaration (Loc,
9906 Make_Function_Specification (Loc,
9907 Defining_Unit_Name => Op_Name,
9908 Parameter_Specifications => Formals,
9909 Result_Definition =>
9910 New_Occurrence_Of (Standard_Boolean, Loc)));
9912 -- Insert inequality right after equality if it is explicit or after
9913 -- the derived type when implicit. These entities are created only
9914 -- for visibility purposes, and eventually replaced in the course
9915 -- of expansion, so they do not need to be attached to the tree and
9916 -- seen by the back-end. Keeping them internal also avoids spurious
9917 -- freezing problems. The declaration is inserted in the tree for
9918 -- analysis, and removed afterwards. If the equality operator comes
9919 -- from an explicit declaration, attach the inequality immediately
9920 -- after. Else the equality is inherited from a derived type
9921 -- declaration, so insert inequality after that declaration.
9923 if No (Alias (S)) then
9924 Insert_After (Unit_Declaration_Node (S), Decl);
9925 elsif Is_List_Member (Parent (S)) then
9926 Insert_After (Parent (S), Decl);
9928 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9931 Mark_Rewrite_Insertion (Decl);
9932 Set_Is_Intrinsic_Subprogram (Op_Name);
9935 Set_Has_Completion (Op_Name);
9936 Set_Corresponding_Equality (Op_Name, S);
9937 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9939 end Make_Inequality_Operator;
9941 ----------------------
9942 -- May_Need_Actuals --
9943 ----------------------
9945 procedure May_Need_Actuals (Fun : Entity_Id) is
9950 F := First_Formal (Fun);
9952 while Present (F) loop
9953 if No (Default_Value (F)) then
9961 Set_Needs_No_Actuals (Fun, B);
9962 end May_Need_Actuals;
9964 ---------------------
9965 -- Mode_Conformant --
9966 ---------------------
9968 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9971 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9973 end Mode_Conformant;
9975 ---------------------------
9976 -- New_Overloaded_Entity --
9977 ---------------------------
9979 procedure New_Overloaded_Entity
9981 Derived_Type : Entity_Id := Empty)
9983 Overridden_Subp : Entity_Id := Empty;
9984 -- Set if the current scope has an operation that is type-conformant
9985 -- with S, and becomes hidden by S.
9987 Is_Primitive_Subp : Boolean;
9988 -- Set to True if the new subprogram is primitive
9991 -- Entity that S overrides
9993 procedure Check_For_Primitive_Subprogram
9994 (Is_Primitive : out Boolean;
9995 Is_Overriding : Boolean := False);
9996 -- If the subprogram being analyzed is a primitive operation of the type
9997 -- of a formal or result, set the Has_Primitive_Operations flag on the
9998 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9999 -- corresponding flag on the entity itself for later use.
10001 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10002 -- True if a) E is a subprogram whose first formal is a concurrent type
10003 -- defined in the scope of E that has some entry or subprogram whose
10004 -- profile matches E, or b) E is an internally built dispatching
10005 -- subprogram of a protected type and there is a matching subprogram
10006 -- defined in the enclosing scope of the protected type, or c) E is
10007 -- an entry of a synchronized type and a matching procedure has been
10008 -- previously defined in the enclosing scope of the synchronized type.
10010 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10011 -- Check that E is declared in the private part of the current package,
10012 -- or in the package body, where it may hide a previous declaration.
10013 -- We can't use In_Private_Part by itself because this flag is also
10014 -- set when freezing entities, so we must examine the place of the
10015 -- declaration in the tree, and recognize wrapper packages as well.
10017 function Is_Overriding_Alias
10018 (Old_E : Entity_Id;
10019 New_E : Entity_Id) return Boolean;
10020 -- Check whether new subprogram and old subprogram are both inherited
10021 -- from subprograms that have distinct dispatch table entries. This can
10022 -- occur with derivations from instances with accidental homonyms. The
10023 -- function is conservative given that the converse is only true within
10024 -- instances that contain accidental overloadings.
10026 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10027 -- Report conflict between entities S and E
10029 ------------------------------------
10030 -- Check_For_Primitive_Subprogram --
10031 ------------------------------------
10033 procedure Check_For_Primitive_Subprogram
10034 (Is_Primitive : out Boolean;
10035 Is_Overriding : Boolean := False)
10037 Formal : Entity_Id;
10041 function Visible_Part_Type (T : Entity_Id) return Boolean;
10042 -- Returns true if T is declared in the visible part of the current
10043 -- package scope; otherwise returns false. Assumes that T is declared
10046 procedure Check_Private_Overriding (T : Entity_Id);
10047 -- Checks that if a primitive abstract subprogram of a visible
10048 -- abstract type is declared in a private part, then it must override
10049 -- an abstract subprogram declared in the visible part. Also checks
10050 -- that if a primitive function with a controlling result is declared
10051 -- in a private part, then it must override a function declared in
10052 -- the visible part.
10054 ------------------------------
10055 -- Check_Private_Overriding --
10056 ------------------------------
10058 procedure Check_Private_Overriding (T : Entity_Id) is
10059 function Overrides_Private_Part_Op return Boolean;
10060 -- This detects the special case where the overriding subprogram
10061 -- is overriding a subprogram that was declared in the same
10062 -- private part. That case is illegal by 3.9.3(10).
10064 function Overrides_Visible_Function
10065 (Partial_View : Entity_Id) return Boolean;
10066 -- True if S overrides a function in the visible part. The
10067 -- overridden function could be explicitly or implicitly declared.
10069 -------------------------------
10070 -- Overrides_Private_Part_Op --
10071 -------------------------------
10073 function Overrides_Private_Part_Op return Boolean is
10074 Over_Decl : constant Node_Id :=
10075 Unit_Declaration_Node (Overridden_Operation (S));
10076 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10079 pragma Assert (Is_Overriding);
10081 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10083 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10085 return In_Same_List (Over_Decl, Subp_Decl);
10086 end Overrides_Private_Part_Op;
10088 --------------------------------
10089 -- Overrides_Visible_Function --
10090 --------------------------------
10092 function Overrides_Visible_Function
10093 (Partial_View : Entity_Id) return Boolean
10096 if not Is_Overriding or else not Has_Homonym (S) then
10100 if not Present (Partial_View) then
10104 -- Search through all the homonyms H of S in the current
10105 -- package spec, and return True if we find one that matches.
10106 -- Note that Parent (H) will be the declaration of the
10107 -- partial view of T for a match.
10110 H : Entity_Id := S;
10114 exit when not Present (H) or else Scope (H) /= Scope (S);
10118 N_Private_Extension_Declaration,
10119 N_Private_Type_Declaration)
10120 and then Defining_Identifier (Parent (H)) = Partial_View
10128 end Overrides_Visible_Function;
10130 -- Start of processing for Check_Private_Overriding
10133 if Is_Package_Or_Generic_Package (Current_Scope)
10134 and then In_Private_Part (Current_Scope)
10135 and then Visible_Part_Type (T)
10136 and then not In_Instance
10138 if Is_Abstract_Type (T)
10139 and then Is_Abstract_Subprogram (S)
10140 and then (not Is_Overriding
10141 or else not Is_Abstract_Subprogram (E)
10142 or else Overrides_Private_Part_Op)
10145 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10148 elsif Ekind (S) = E_Function then
10150 Partial_View : constant Entity_Id :=
10151 Incomplete_Or_Partial_View (T);
10154 if not Overrides_Visible_Function (Partial_View) then
10156 -- Here, S is "function ... return T;" declared in
10157 -- the private part, not overriding some visible
10158 -- operation. That's illegal in the tagged case
10159 -- (but not if the private type is untagged).
10161 if ((Present (Partial_View)
10162 and then Is_Tagged_Type (Partial_View))
10163 or else (not Present (Partial_View)
10164 and then Is_Tagged_Type (T)))
10165 and then T = Base_Type (Etype (S))
10168 ("private function with tagged result must"
10169 & " override visible-part function", S);
10171 ("\move subprogram to the visible part"
10172 & " (RM 3.9.3(10))", S);
10174 -- AI05-0073: extend this test to the case of a
10175 -- function with a controlling access result.
10177 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10178 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10180 not Is_Class_Wide_Type
10181 (Designated_Type (Etype (S)))
10182 and then Ada_Version >= Ada_2012
10185 ("private function with controlling access "
10186 & "result must override visible-part function",
10189 ("\move subprogram to the visible part"
10190 & " (RM 3.9.3(10))", S);
10196 end Check_Private_Overriding;
10198 -----------------------
10199 -- Visible_Part_Type --
10200 -----------------------
10202 function Visible_Part_Type (T : Entity_Id) return Boolean is
10203 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10206 -- If the entity is a private type, then it must be declared in a
10209 if Ekind (T) in Private_Kind then
10212 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10215 elsif Is_List_Member (Declaration_Node (T))
10216 and then List_Containing (Declaration_Node (T)) =
10217 Visible_Declarations (Specification (P))
10224 end Visible_Part_Type;
10226 -- Start of processing for Check_For_Primitive_Subprogram
10229 Is_Primitive := False;
10231 if not Comes_From_Source (S) then
10234 -- If subprogram is at library level, it is not primitive operation
10236 elsif Current_Scope = Standard_Standard then
10239 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10240 and then not In_Package_Body (Current_Scope))
10241 or else Is_Overriding
10243 -- For function, check return type
10245 if Ekind (S) = E_Function then
10246 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10247 F_Typ := Designated_Type (Etype (S));
10249 F_Typ := Etype (S);
10252 B_Typ := Base_Type (F_Typ);
10254 if Scope (B_Typ) = Current_Scope
10255 and then not Is_Class_Wide_Type (B_Typ)
10256 and then not Is_Generic_Type (B_Typ)
10258 Is_Primitive := True;
10259 Set_Has_Primitive_Operations (B_Typ);
10260 Set_Is_Primitive (S);
10261 Check_Private_Overriding (B_Typ);
10263 -- The Ghost policy in effect at the point of declaration
10264 -- or a tagged type and a primitive operation must match
10265 -- (SPARK RM 6.9(16)).
10267 Check_Ghost_Primitive (S, B_Typ);
10271 -- For all subprograms, check formals
10273 Formal := First_Formal (S);
10274 while Present (Formal) loop
10275 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10276 F_Typ := Designated_Type (Etype (Formal));
10278 F_Typ := Etype (Formal);
10281 B_Typ := Base_Type (F_Typ);
10283 if Ekind (B_Typ) = E_Access_Subtype then
10284 B_Typ := Base_Type (B_Typ);
10287 if Scope (B_Typ) = Current_Scope
10288 and then not Is_Class_Wide_Type (B_Typ)
10289 and then not Is_Generic_Type (B_Typ)
10291 Is_Primitive := True;
10292 Set_Is_Primitive (S);
10293 Set_Has_Primitive_Operations (B_Typ);
10294 Check_Private_Overriding (B_Typ);
10296 -- The Ghost policy in effect at the point of declaration
10297 -- of a tagged type and a primitive operation must match
10298 -- (SPARK RM 6.9(16)).
10300 Check_Ghost_Primitive (S, B_Typ);
10303 Next_Formal (Formal);
10306 -- Special case: An equality function can be redefined for a type
10307 -- occurring in a declarative part, and won't otherwise be treated as
10308 -- a primitive because it doesn't occur in a package spec and doesn't
10309 -- override an inherited subprogram. It's important that we mark it
10310 -- primitive so it can be returned by Collect_Primitive_Operations
10311 -- and be used in composing the equality operation of later types
10312 -- that have a component of the type.
10314 elsif Chars (S) = Name_Op_Eq
10315 and then Etype (S) = Standard_Boolean
10317 B_Typ := Base_Type (Etype (First_Formal (S)));
10319 if Scope (B_Typ) = Current_Scope
10321 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10322 and then not Is_Limited_Type (B_Typ)
10324 Is_Primitive := True;
10325 Set_Is_Primitive (S);
10326 Set_Has_Primitive_Operations (B_Typ);
10327 Check_Private_Overriding (B_Typ);
10329 -- The Ghost policy in effect at the point of declaration of a
10330 -- tagged type and a primitive operation must match
10331 -- (SPARK RM 6.9(16)).
10333 Check_Ghost_Primitive (S, B_Typ);
10336 end Check_For_Primitive_Subprogram;
10338 --------------------------------------
10339 -- Has_Matching_Entry_Or_Subprogram --
10340 --------------------------------------
10342 function Has_Matching_Entry_Or_Subprogram
10343 (E : Entity_Id) return Boolean
10345 function Check_Conforming_Parameters
10346 (E1_Param : Node_Id;
10347 E2_Param : Node_Id) return Boolean;
10348 -- Starting from the given parameters, check that all the parameters
10349 -- of two entries or subprograms are subtype conformant. Used to skip
10350 -- the check on the controlling argument.
10352 function Matching_Entry_Or_Subprogram
10353 (Conc_Typ : Entity_Id;
10354 Subp : Entity_Id) return Entity_Id;
10355 -- Return the first entry or subprogram of the given concurrent type
10356 -- whose name matches the name of Subp and has a profile conformant
10357 -- with Subp; return Empty if not found.
10359 function Matching_Dispatching_Subprogram
10360 (Conc_Typ : Entity_Id;
10361 Ent : Entity_Id) return Entity_Id;
10362 -- Return the first dispatching primitive of Conc_Type defined in the
10363 -- enclosing scope of Conc_Type (i.e. before the full definition of
10364 -- this concurrent type) whose name matches the entry Ent and has a
10365 -- profile conformant with the profile of the corresponding (not yet
10366 -- built) dispatching primitive of Ent; return Empty if not found.
10368 function Matching_Original_Protected_Subprogram
10369 (Prot_Typ : Entity_Id;
10370 Subp : Entity_Id) return Entity_Id;
10371 -- Return the first subprogram defined in the enclosing scope of
10372 -- Prot_Typ (before the full definition of this protected type)
10373 -- whose name matches the original name of Subp and has a profile
10374 -- conformant with the profile of Subp; return Empty if not found.
10376 ---------------------------------
10377 -- Check_Conforming_Parameters --
10378 ---------------------------------
10380 function Check_Conforming_Parameters
10381 (E1_Param : Node_Id;
10382 E2_Param : Node_Id) return Boolean
10384 Param_E1 : Node_Id := E1_Param;
10385 Param_E2 : Node_Id := E2_Param;
10388 while Present (Param_E1) and then Present (Param_E2) loop
10389 if Ekind (Defining_Identifier (Param_E1)) /=
10390 Ekind (Defining_Identifier (Param_E2))
10393 (Find_Parameter_Type (Param_E1),
10394 Find_Parameter_Type (Param_E2),
10395 Subtype_Conformant)
10404 -- The candidate is not valid if one of the two lists contains
10405 -- more parameters than the other
10407 return No (Param_E1) and then No (Param_E2);
10408 end Check_Conforming_Parameters;
10410 ----------------------------------
10411 -- Matching_Entry_Or_Subprogram --
10412 ----------------------------------
10414 function Matching_Entry_Or_Subprogram
10415 (Conc_Typ : Entity_Id;
10416 Subp : Entity_Id) return Entity_Id
10421 E := First_Entity (Conc_Typ);
10422 while Present (E) loop
10423 if Chars (Subp) = Chars (E)
10424 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10426 Check_Conforming_Parameters
10427 (First (Parameter_Specifications (Parent (E))),
10428 Next (First (Parameter_Specifications (Parent (Subp)))))
10437 end Matching_Entry_Or_Subprogram;
10439 -------------------------------------
10440 -- Matching_Dispatching_Subprogram --
10441 -------------------------------------
10443 function Matching_Dispatching_Subprogram
10444 (Conc_Typ : Entity_Id;
10445 Ent : Entity_Id) return Entity_Id
10450 -- Search for entities in the enclosing scope of this synchonized
10453 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10454 Push_Scope (Scope (Conc_Typ));
10455 E := Current_Entity_In_Scope (Ent);
10458 while Present (E) loop
10459 if Scope (E) = Scope (Conc_Typ)
10460 and then Comes_From_Source (E)
10461 and then Ekind (E) = E_Procedure
10462 and then Present (First_Entity (E))
10463 and then Is_Controlling_Formal (First_Entity (E))
10464 and then Etype (First_Entity (E)) = Conc_Typ
10466 Check_Conforming_Parameters
10467 (First (Parameter_Specifications (Parent (Ent))),
10468 Next (First (Parameter_Specifications (Parent (E)))))
10477 end Matching_Dispatching_Subprogram;
10479 --------------------------------------------
10480 -- Matching_Original_Protected_Subprogram --
10481 --------------------------------------------
10483 function Matching_Original_Protected_Subprogram
10484 (Prot_Typ : Entity_Id;
10485 Subp : Entity_Id) return Entity_Id
10487 ICF : constant Boolean :=
10488 Is_Controlling_Formal (First_Entity (Subp));
10492 -- Temporarily decorate the first parameter of Subp as controlling
10493 -- formal, required to invoke Subtype_Conformant.
10495 Set_Is_Controlling_Formal (First_Entity (Subp));
10498 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10500 while Present (E) loop
10501 if Scope (E) = Scope (Prot_Typ)
10502 and then Comes_From_Source (E)
10503 and then Ekind (Subp) = Ekind (E)
10504 and then Present (First_Entity (E))
10505 and then Is_Controlling_Formal (First_Entity (E))
10506 and then Etype (First_Entity (E)) = Prot_Typ
10507 and then Subtype_Conformant (Subp, E,
10508 Skip_Controlling_Formals => True)
10510 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10517 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10520 end Matching_Original_Protected_Subprogram;
10522 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10525 -- Case 1: E is a subprogram whose first formal is a concurrent type
10526 -- defined in the scope of E that has an entry or subprogram whose
10527 -- profile matches E.
10529 if Comes_From_Source (E)
10530 and then Is_Subprogram (E)
10531 and then Present (First_Entity (E))
10532 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10535 Scope (Corresponding_Concurrent_Type
10536 (Etype (First_Entity (E))))
10539 (Matching_Entry_Or_Subprogram
10540 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10543 Report_Conflict (E,
10544 Matching_Entry_Or_Subprogram
10545 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10550 -- Case 2: E is an internally built dispatching subprogram of a
10551 -- protected type and there is a subprogram defined in the enclosing
10552 -- scope of the protected type that has the original name of E and
10553 -- its profile is conformant with the profile of E. We check the
10554 -- name of the original protected subprogram associated with E since
10555 -- the expander builds dispatching primitives of protected functions
10556 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10558 elsif not Comes_From_Source (E)
10559 and then Is_Subprogram (E)
10560 and then Present (First_Entity (E))
10561 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10562 and then Present (Original_Protected_Subprogram (E))
10565 (Matching_Original_Protected_Subprogram
10566 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10569 Report_Conflict (E,
10570 Matching_Original_Protected_Subprogram
10571 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10575 -- Case 3: E is an entry of a synchronized type and a matching
10576 -- procedure has been previously defined in the enclosing scope
10577 -- of the synchronized type.
10579 elsif Comes_From_Source (E)
10580 and then Ekind (E) = E_Entry
10582 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10584 Report_Conflict (E,
10585 Matching_Dispatching_Subprogram (Current_Scope, E));
10590 end Has_Matching_Entry_Or_Subprogram;
10592 ----------------------------
10593 -- Is_Private_Declaration --
10594 ----------------------------
10596 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10597 Decl : constant Node_Id := Unit_Declaration_Node (E);
10598 Priv_Decls : List_Id;
10601 if Is_Package_Or_Generic_Package (Current_Scope)
10602 and then In_Private_Part (Current_Scope)
10605 Private_Declarations (Package_Specification (Current_Scope));
10607 return In_Package_Body (Current_Scope)
10609 (Is_List_Member (Decl)
10610 and then List_Containing (Decl) = Priv_Decls)
10611 or else (Nkind (Parent (Decl)) = N_Package_Specification
10613 Is_Compilation_Unit
10614 (Defining_Entity (Parent (Decl)))
10615 and then List_Containing (Parent (Parent (Decl))) =
10620 end Is_Private_Declaration;
10622 --------------------------
10623 -- Is_Overriding_Alias --
10624 --------------------------
10626 function Is_Overriding_Alias
10627 (Old_E : Entity_Id;
10628 New_E : Entity_Id) return Boolean
10630 AO : constant Entity_Id := Alias (Old_E);
10631 AN : constant Entity_Id := Alias (New_E);
10634 return Scope (AO) /= Scope (AN)
10635 or else No (DTC_Entity (AO))
10636 or else No (DTC_Entity (AN))
10637 or else DT_Position (AO) = DT_Position (AN);
10638 end Is_Overriding_Alias;
10640 ---------------------
10641 -- Report_Conflict --
10642 ---------------------
10644 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10646 Error_Msg_Sloc := Sloc (E);
10648 -- Generate message, with useful additional warning if in generic
10650 if Is_Generic_Unit (E) then
10651 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10652 Error_Msg_N ("\& conflicts with declaration#", S);
10654 Error_Msg_N ("& conflicts with declaration#", S);
10656 end Report_Conflict;
10658 -- Start of processing for New_Overloaded_Entity
10661 -- We need to look for an entity that S may override. This must be a
10662 -- homonym in the current scope, so we look for the first homonym of
10663 -- S in the current scope as the starting point for the search.
10665 E := Current_Entity_In_Scope (S);
10667 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10668 -- They are directly added to the list of primitive operations of
10669 -- Derived_Type, unless this is a rederivation in the private part
10670 -- of an operation that was already derived in the visible part of
10671 -- the current package.
10673 if Ada_Version >= Ada_2005
10674 and then Present (Derived_Type)
10675 and then Present (Alias (S))
10676 and then Is_Dispatching_Operation (Alias (S))
10677 and then Present (Find_Dispatching_Type (Alias (S)))
10678 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10680 -- For private types, when the full-view is processed we propagate to
10681 -- the full view the non-overridden entities whose attribute "alias"
10682 -- references an interface primitive. These entities were added by
10683 -- Derive_Subprograms to ensure that interface primitives are
10686 -- Inside_Freeze_Actions is non zero when S corresponds with an
10687 -- internal entity that links an interface primitive with its
10688 -- covering primitive through attribute Interface_Alias (see
10689 -- Add_Internal_Interface_Entities).
10691 if Inside_Freezing_Actions = 0
10692 and then Is_Package_Or_Generic_Package (Current_Scope)
10693 and then In_Private_Part (Current_Scope)
10694 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10695 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10696 and then Full_View (Defining_Identifier (Parent (E)))
10697 = Defining_Identifier (Parent (S))
10698 and then Alias (E) = Alias (S)
10700 Check_Operation_From_Private_View (S, E);
10701 Set_Is_Dispatching_Operation (S);
10706 Enter_Overloaded_Entity (S);
10707 Check_Dispatching_Operation (S, Empty);
10708 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10714 -- For synchronized types check conflicts of this entity with previously
10715 -- defined entities.
10717 if Ada_Version >= Ada_2005
10718 and then Has_Matching_Entry_Or_Subprogram (S)
10723 -- If there is no homonym then this is definitely not overriding
10726 Enter_Overloaded_Entity (S);
10727 Check_Dispatching_Operation (S, Empty);
10728 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10730 -- If subprogram has an explicit declaration, check whether it has an
10731 -- overriding indicator.
10733 if Comes_From_Source (S) then
10734 Check_Synchronized_Overriding (S, Overridden_Subp);
10736 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10737 -- it may have overridden some hidden inherited primitive. Update
10738 -- Overridden_Subp to avoid spurious errors when checking the
10739 -- overriding indicator.
10741 if Ada_Version >= Ada_2012
10742 and then No (Overridden_Subp)
10743 and then Is_Dispatching_Operation (S)
10744 and then Present (Overridden_Operation (S))
10746 Overridden_Subp := Overridden_Operation (S);
10749 Check_Overriding_Indicator
10750 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10752 -- The Ghost policy in effect at the point of declaration of a
10753 -- parent subprogram and an overriding subprogram must match
10754 -- (SPARK RM 6.9(17)).
10756 Check_Ghost_Overriding (S, Overridden_Subp);
10759 -- If there is a homonym that is not overloadable, then we have an
10760 -- error, except for the special cases checked explicitly below.
10762 elsif not Is_Overloadable (E) then
10764 -- Check for spurious conflict produced by a subprogram that has the
10765 -- same name as that of the enclosing generic package. The conflict
10766 -- occurs within an instance, between the subprogram and the renaming
10767 -- declaration for the package. After the subprogram, the package
10768 -- renaming declaration becomes hidden.
10770 if Ekind (E) = E_Package
10771 and then Present (Renamed_Object (E))
10772 and then Renamed_Object (E) = Current_Scope
10773 and then Nkind (Parent (Renamed_Object (E))) =
10774 N_Package_Specification
10775 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10778 Set_Is_Immediately_Visible (E, False);
10779 Enter_Overloaded_Entity (S);
10780 Set_Homonym (S, Homonym (E));
10781 Check_Dispatching_Operation (S, Empty);
10782 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10784 -- If the subprogram is implicit it is hidden by the previous
10785 -- declaration. However if it is dispatching, it must appear in the
10786 -- dispatch table anyway, because it can be dispatched to even if it
10787 -- cannot be called directly.
10789 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10790 Set_Scope (S, Current_Scope);
10792 if Is_Dispatching_Operation (Alias (S)) then
10793 Check_Dispatching_Operation (S, Empty);
10799 Report_Conflict (S, E);
10803 -- E exists and is overloadable
10806 Check_Synchronized_Overriding (S, Overridden_Subp);
10808 -- Loop through E and its homonyms to determine if any of them is
10809 -- the candidate for overriding by S.
10811 while Present (E) loop
10813 -- Definitely not interesting if not in the current scope
10815 if Scope (E) /= Current_Scope then
10818 -- A function can overload the name of an abstract state. The
10819 -- state can be viewed as a function with a profile that cannot
10820 -- be matched by anything.
10822 elsif Ekind (S) = E_Function
10823 and then Ekind (E) = E_Abstract_State
10825 Enter_Overloaded_Entity (S);
10828 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10829 -- procedures locate the internally generated spec. We enforce
10830 -- mode conformance since a tagged type may inherit from
10831 -- interfaces several null primitives which differ only in
10832 -- the mode of the formals.
10834 elsif not Comes_From_Source (S)
10835 and then Is_Null_Procedure (S)
10836 and then not Mode_Conformant (E, S)
10840 -- Check if we have type conformance
10842 elsif Type_Conformant (E, S) then
10844 -- If the old and new entities have the same profile and one
10845 -- is not the body of the other, then this is an error, unless
10846 -- one of them is implicitly declared.
10848 -- There are some cases when both can be implicit, for example
10849 -- when both a literal and a function that overrides it are
10850 -- inherited in a derivation, or when an inherited operation
10851 -- of a tagged full type overrides the inherited operation of
10852 -- a private extension. Ada 83 had a special rule for the
10853 -- literal case. In Ada 95, the later implicit operation hides
10854 -- the former, and the literal is always the former. In the
10855 -- odd case where both are derived operations declared at the
10856 -- same point, both operations should be declared, and in that
10857 -- case we bypass the following test and proceed to the next
10858 -- part. This can only occur for certain obscure cases in
10859 -- instances, when an operation on a type derived from a formal
10860 -- private type does not override a homograph inherited from
10861 -- the actual. In subsequent derivations of such a type, the
10862 -- DT positions of these operations remain distinct, if they
10865 if Present (Alias (S))
10866 and then (No (Alias (E))
10867 or else Comes_From_Source (E)
10868 or else Is_Abstract_Subprogram (S)
10870 (Is_Dispatching_Operation (E)
10871 and then Is_Overriding_Alias (E, S)))
10872 and then Ekind (E) /= E_Enumeration_Literal
10874 -- When an derived operation is overloaded it may be due to
10875 -- the fact that the full view of a private extension
10876 -- re-inherits. It has to be dealt with.
10878 if Is_Package_Or_Generic_Package (Current_Scope)
10879 and then In_Private_Part (Current_Scope)
10881 Check_Operation_From_Private_View (S, E);
10884 -- In any case the implicit operation remains hidden by the
10885 -- existing declaration, which is overriding. Indicate that
10886 -- E overrides the operation from which S is inherited.
10888 if Present (Alias (S)) then
10889 Set_Overridden_Operation (E, Alias (S));
10890 Inherit_Subprogram_Contract (E, Alias (S));
10893 Set_Overridden_Operation (E, S);
10894 Inherit_Subprogram_Contract (E, S);
10897 if Comes_From_Source (E) then
10898 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10900 -- The Ghost policy in effect at the point of declaration
10901 -- of a parent subprogram and an overriding subprogram
10902 -- must match (SPARK RM 6.9(17)).
10904 Check_Ghost_Overriding (E, S);
10909 -- Within an instance, the renaming declarations for actual
10910 -- subprograms may become ambiguous, but they do not hide each
10913 elsif Ekind (E) /= E_Entry
10914 and then not Comes_From_Source (E)
10915 and then not Is_Generic_Instance (E)
10916 and then (Present (Alias (E))
10917 or else Is_Intrinsic_Subprogram (E))
10918 and then (not In_Instance
10919 or else No (Parent (E))
10920 or else Nkind (Unit_Declaration_Node (E)) /=
10921 N_Subprogram_Renaming_Declaration)
10923 -- A subprogram child unit is not allowed to override an
10924 -- inherited subprogram (10.1.1(20)).
10926 if Is_Child_Unit (S) then
10928 ("child unit overrides inherited subprogram in parent",
10933 if Is_Non_Overriding_Operation (E, S) then
10934 Enter_Overloaded_Entity (S);
10936 if No (Derived_Type)
10937 or else Is_Tagged_Type (Derived_Type)
10939 Check_Dispatching_Operation (S, Empty);
10945 -- E is a derived operation or an internal operator which
10946 -- is being overridden. Remove E from further visibility.
10947 -- Furthermore, if E is a dispatching operation, it must be
10948 -- replaced in the list of primitive operations of its type
10949 -- (see Override_Dispatching_Operation).
10951 Overridden_Subp := E;
10953 -- It is possible for E to be in the current scope and
10954 -- yet not in the entity chain. This can only occur in a
10955 -- generic context where E is an implicit concatenation
10956 -- in the formal part, because in a generic body the
10957 -- entity chain starts with the formals.
10959 -- In GNATprove mode, a wrapper for an operation with
10960 -- axiomatization may be a homonym of another declaration
10961 -- for an actual subprogram (needs refinement ???).
10963 if No (Prev_Entity (E)) then
10965 and then GNATprove_Mode
10967 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10968 N_Subprogram_Renaming_Declaration
10972 pragma Assert (Chars (E) = Name_Op_Concat);
10977 -- E must be removed both from the entity_list of the
10978 -- current scope, and from the visibility chain.
10980 if Debug_Flag_E then
10981 Write_Str ("Override implicit operation ");
10982 Write_Int (Int (E));
10986 -- If E is a predefined concatenation, it stands for four
10987 -- different operations. As a result, a single explicit
10988 -- declaration does not hide it. In a possible ambiguous
10989 -- situation, Disambiguate chooses the user-defined op,
10990 -- so it is correct to retain the previous internal one.
10992 if Chars (E) /= Name_Op_Concat
10993 or else Ekind (E) /= E_Operator
10995 -- For nondispatching derived operations that are
10996 -- overridden by a subprogram declared in the private
10997 -- part of a package, we retain the derived subprogram
10998 -- but mark it as not immediately visible. If the
10999 -- derived operation was declared in the visible part
11000 -- then this ensures that it will still be visible
11001 -- outside the package with the proper signature
11002 -- (calls from outside must also be directed to this
11003 -- version rather than the overriding one, unlike the
11004 -- dispatching case). Calls from inside the package
11005 -- will still resolve to the overriding subprogram
11006 -- since the derived one is marked as not visible
11007 -- within the package.
11009 -- If the private operation is dispatching, we achieve
11010 -- the overriding by keeping the implicit operation
11011 -- but setting its alias to be the overriding one. In
11012 -- this fashion the proper body is executed in all
11013 -- cases, but the original signature is used outside
11016 -- If the overriding is not in the private part, we
11017 -- remove the implicit operation altogether.
11019 if Is_Private_Declaration (S) then
11020 if not Is_Dispatching_Operation (E) then
11021 Set_Is_Immediately_Visible (E, False);
11023 -- Work done in Override_Dispatching_Operation, so
11024 -- nothing else needs to be done here.
11030 Remove_Entity_And_Homonym (E);
11034 Enter_Overloaded_Entity (S);
11036 -- For entities generated by Derive_Subprograms the
11037 -- overridden operation is the inherited primitive
11038 -- (which is available through the attribute alias).
11040 if not (Comes_From_Source (E))
11041 and then Is_Dispatching_Operation (E)
11042 and then Find_Dispatching_Type (E) =
11043 Find_Dispatching_Type (S)
11044 and then Present (Alias (E))
11045 and then Comes_From_Source (Alias (E))
11047 Set_Overridden_Operation (S, Alias (E));
11048 Inherit_Subprogram_Contract (S, Alias (E));
11050 -- Normal case of setting entity as overridden
11052 -- Note: Static_Initialization and Overridden_Operation
11053 -- attributes use the same field in subprogram entities.
11054 -- Static_Initialization is only defined for internal
11055 -- initialization procedures, where Overridden_Operation
11056 -- is irrelevant. Therefore the setting of this attribute
11057 -- must check whether the target is an init_proc.
11059 elsif not Is_Init_Proc (S) then
11060 Set_Overridden_Operation (S, E);
11061 Inherit_Subprogram_Contract (S, E);
11064 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11066 -- The Ghost policy in effect at the point of declaration
11067 -- of a parent subprogram and an overriding subprogram
11068 -- must match (SPARK RM 6.9(17)).
11070 Check_Ghost_Overriding (S, E);
11072 -- If S is a user-defined subprogram or a null procedure
11073 -- expanded to override an inherited null procedure, or a
11074 -- predefined dispatching primitive then indicate that E
11075 -- overrides the operation from which S is inherited.
11077 if Comes_From_Source (S)
11079 (Present (Parent (S))
11080 and then Nkind (Parent (S)) = N_Procedure_Specification
11081 and then Null_Present (Parent (S)))
11083 (Present (Alias (E))
11085 Is_Predefined_Dispatching_Operation (Alias (E)))
11087 if Present (Alias (E)) then
11088 Set_Overridden_Operation (S, Alias (E));
11089 Inherit_Subprogram_Contract (S, Alias (E));
11093 if Is_Dispatching_Operation (E) then
11095 -- An overriding dispatching subprogram inherits the
11096 -- convention of the overridden subprogram (AI-117).
11098 Set_Convention (S, Convention (E));
11099 Check_Dispatching_Operation (S, E);
11102 Check_Dispatching_Operation (S, Empty);
11105 Check_For_Primitive_Subprogram
11106 (Is_Primitive_Subp, Is_Overriding => True);
11107 goto Check_Inequality;
11109 -- Apparent redeclarations in instances can occur when two
11110 -- formal types get the same actual type. The subprograms in
11111 -- in the instance are legal, even if not callable from the
11112 -- outside. Calls from within are disambiguated elsewhere.
11113 -- For dispatching operations in the visible part, the usual
11114 -- rules apply, and operations with the same profile are not
11115 -- legal (B830001).
11117 elsif (In_Instance_Visible_Part
11118 and then not Is_Dispatching_Operation (E))
11119 or else In_Instance_Not_Visible
11123 -- Here we have a real error (identical profile)
11126 Error_Msg_Sloc := Sloc (E);
11128 -- Avoid cascaded errors if the entity appears in
11129 -- subsequent calls.
11131 Set_Scope (S, Current_Scope);
11133 -- Generate error, with extra useful warning for the case
11134 -- of a generic instance with no completion.
11136 if Is_Generic_Instance (S)
11137 and then not Has_Completion (E)
11140 ("instantiation cannot provide body for&", S);
11141 Error_Msg_N ("\& conflicts with declaration#", S);
11143 Error_Msg_N ("& conflicts with declaration#", S);
11150 -- If one subprogram has an access parameter and the other
11151 -- a parameter of an access type, calls to either might be
11152 -- ambiguous. Verify that parameters match except for the
11153 -- access parameter.
11155 if May_Hide_Profile then
11161 F1 := First_Formal (S);
11162 F2 := First_Formal (E);
11163 while Present (F1) and then Present (F2) loop
11164 if Is_Access_Type (Etype (F1)) then
11165 if not Is_Access_Type (Etype (F2))
11166 or else not Conforming_Types
11167 (Designated_Type (Etype (F1)),
11168 Designated_Type (Etype (F2)),
11171 May_Hide_Profile := False;
11175 not Conforming_Types
11176 (Etype (F1), Etype (F2), Type_Conformant)
11178 May_Hide_Profile := False;
11185 if May_Hide_Profile
11189 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11198 -- On exit, we know that S is a new entity
11200 Enter_Overloaded_Entity (S);
11201 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11202 Check_Overriding_Indicator
11203 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11205 -- The Ghost policy in effect at the point of declaration of a parent
11206 -- subprogram and an overriding subprogram must match
11207 -- (SPARK RM 6.9(17)).
11209 Check_Ghost_Overriding (S, Overridden_Subp);
11211 -- Overloading is not allowed in SPARK, except for operators
11213 if Nkind (S) /= N_Defining_Operator_Symbol then
11214 Error_Msg_Sloc := Sloc (Homonym (S));
11215 Check_SPARK_05_Restriction
11216 ("overloading not allowed with entity#", S);
11219 -- If S is a derived operation for an untagged type then by
11220 -- definition it's not a dispatching operation (even if the parent
11221 -- operation was dispatching), so Check_Dispatching_Operation is not
11222 -- called in that case.
11224 if No (Derived_Type)
11225 or else Is_Tagged_Type (Derived_Type)
11227 Check_Dispatching_Operation (S, Empty);
11231 -- If this is a user-defined equality operator that is not a derived
11232 -- subprogram, create the corresponding inequality. If the operation is
11233 -- dispatching, the expansion is done elsewhere, and we do not create
11234 -- an explicit inequality operation.
11236 <<Check_Inequality>>
11237 if Chars (S) = Name_Op_Eq
11238 and then Etype (S) = Standard_Boolean
11239 and then Present (Parent (S))
11240 and then not Is_Dispatching_Operation (S)
11242 Make_Inequality_Operator (S);
11243 Check_Untagged_Equality (S);
11245 end New_Overloaded_Entity;
11247 ----------------------------------
11248 -- Preanalyze_Formal_Expression --
11249 ----------------------------------
11251 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id) is
11252 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
11254 In_Spec_Expression := True;
11255 Preanalyze_With_Freezing_And_Resolve (N, T);
11256 In_Spec_Expression := Save_In_Spec_Expression;
11257 end Preanalyze_Formal_Expression;
11259 ---------------------
11260 -- Process_Formals --
11261 ---------------------
11263 procedure Process_Formals
11265 Related_Nod : Node_Id)
11267 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11268 -- Determine whether an access type designates a type coming from a
11271 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11272 -- Check whether the default has a class-wide type. After analysis the
11273 -- default has the type of the formal, so we must also check explicitly
11274 -- for an access attribute.
11276 ----------------------------------
11277 -- Designates_From_Limited_With --
11278 ----------------------------------
11280 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11281 Desig : Entity_Id := Typ;
11284 if Is_Access_Type (Desig) then
11285 Desig := Directly_Designated_Type (Desig);
11288 if Is_Class_Wide_Type (Desig) then
11289 Desig := Root_Type (Desig);
11293 Ekind (Desig) = E_Incomplete_Type
11294 and then From_Limited_With (Desig);
11295 end Designates_From_Limited_With;
11297 ---------------------------
11298 -- Is_Class_Wide_Default --
11299 ---------------------------
11301 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11303 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11304 or else (Nkind (D) = N_Attribute_Reference
11305 and then Attribute_Name (D) = Name_Access
11306 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11307 end Is_Class_Wide_Default;
11311 Context : constant Node_Id := Parent (Parent (T));
11313 Formal : Entity_Id;
11314 Formal_Type : Entity_Id;
11315 Param_Spec : Node_Id;
11318 Num_Out_Params : Nat := 0;
11319 First_Out_Param : Entity_Id := Empty;
11320 -- Used for setting Is_Only_Out_Parameter
11322 -- Start of processing for Process_Formals
11325 -- In order to prevent premature use of the formals in the same formal
11326 -- part, the Ekind is left undefined until all default expressions are
11327 -- analyzed. The Ekind is established in a separate loop at the end.
11329 Param_Spec := First (T);
11330 while Present (Param_Spec) loop
11331 Formal := Defining_Identifier (Param_Spec);
11332 Set_Never_Set_In_Source (Formal, True);
11333 Enter_Name (Formal);
11335 -- Case of ordinary parameters
11337 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11338 Find_Type (Parameter_Type (Param_Spec));
11339 Ptype := Parameter_Type (Param_Spec);
11341 if Ptype = Error then
11345 Formal_Type := Entity (Ptype);
11347 if Is_Incomplete_Type (Formal_Type)
11349 (Is_Class_Wide_Type (Formal_Type)
11350 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11352 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11353 -- primitive operations, as long as their completion is
11354 -- in the same declarative part. If in the private part
11355 -- this means that the type cannot be a Taft-amendment type.
11356 -- Check is done on package exit. For access to subprograms,
11357 -- the use is legal for Taft-amendment types.
11359 -- Ada 2012: tagged incomplete types are allowed as generic
11360 -- formal types. They do not introduce dependencies and the
11361 -- corresponding generic subprogram does not have a delayed
11362 -- freeze, because it does not need a freeze node. However,
11363 -- it is still the case that untagged incomplete types cannot
11364 -- be Taft-amendment types and must be completed in private
11365 -- part, so the subprogram must appear in the list of private
11366 -- dependents of the type.
11368 if Is_Tagged_Type (Formal_Type)
11369 or else (Ada_Version >= Ada_2012
11370 and then not From_Limited_With (Formal_Type)
11371 and then not Is_Generic_Type (Formal_Type))
11373 if Ekind (Scope (Current_Scope)) = E_Package
11374 and then not Is_Generic_Type (Formal_Type)
11375 and then not Is_Class_Wide_Type (Formal_Type)
11378 (Parent (T), N_Access_Function_Definition,
11379 N_Access_Procedure_Definition)
11381 Append_Elmt (Current_Scope,
11382 Private_Dependents (Base_Type (Formal_Type)));
11384 -- Freezing is delayed to ensure that Register_Prim
11385 -- will get called for this operation, which is needed
11386 -- in cases where static dispatch tables aren't built.
11387 -- (Note that the same is done for controlling access
11388 -- parameter cases in function Access_Definition.)
11390 if not Is_Thunk (Current_Scope) then
11391 Set_Has_Delayed_Freeze (Current_Scope);
11396 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11397 N_Access_Procedure_Definition)
11399 -- AI05-0151: Tagged incomplete types are allowed in all
11400 -- formal parts. Untagged incomplete types are not allowed
11401 -- in bodies. Limited views of either kind are not allowed
11402 -- if there is no place at which the non-limited view can
11403 -- become available.
11405 -- Incomplete formal untagged types are not allowed in
11406 -- subprogram bodies (but are legal in their declarations).
11407 -- This excludes bodies created for null procedures, which
11408 -- are basic declarations.
11410 if Is_Generic_Type (Formal_Type)
11411 and then not Is_Tagged_Type (Formal_Type)
11412 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11415 ("invalid use of formal incomplete type", Param_Spec);
11417 elsif Ada_Version >= Ada_2012 then
11418 if Is_Tagged_Type (Formal_Type)
11419 and then (not From_Limited_With (Formal_Type)
11420 or else not In_Package_Body)
11424 elsif Nkind_In (Context, N_Accept_Statement,
11425 N_Accept_Alternative,
11427 or else (Nkind (Context) = N_Subprogram_Body
11428 and then Comes_From_Source (Context))
11431 ("invalid use of untagged incomplete type &",
11432 Ptype, Formal_Type);
11437 ("invalid use of incomplete type&",
11438 Param_Spec, Formal_Type);
11440 -- Further checks on the legality of incomplete types
11441 -- in formal parts are delayed until the freeze point
11442 -- of the enclosing subprogram or access to subprogram.
11446 elsif Ekind (Formal_Type) = E_Void then
11448 ("premature use of&",
11449 Parameter_Type (Param_Spec), Formal_Type);
11452 -- Ada 2012 (AI-142): Handle aliased parameters
11454 if Ada_Version >= Ada_2012
11455 and then Aliased_Present (Param_Spec)
11457 Set_Is_Aliased (Formal);
11460 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11461 -- declaration corresponding to the null-excluding type of the
11462 -- formal in the enclosing scope. Finally, replace the parameter
11463 -- type of the formal with the internal subtype.
11465 if Ada_Version >= Ada_2005
11466 and then Null_Exclusion_Present (Param_Spec)
11468 if not Is_Access_Type (Formal_Type) then
11470 ("`NOT NULL` allowed only for an access type", Param_Spec);
11473 if Can_Never_Be_Null (Formal_Type)
11474 and then Comes_From_Source (Related_Nod)
11477 ("`NOT NULL` not allowed (& already excludes null)",
11478 Param_Spec, Formal_Type);
11482 Create_Null_Excluding_Itype
11484 Related_Nod => Related_Nod,
11485 Scope_Id => Scope (Current_Scope));
11487 -- If the designated type of the itype is an itype that is
11488 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11489 -- on the access subtype, to prevent order-of-elaboration
11490 -- issues in the backend.
11493 -- type T is access procedure;
11494 -- procedure Op (O : not null T);
11496 if Is_Itype (Directly_Designated_Type (Formal_Type))
11498 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11500 Set_Has_Delayed_Freeze (Formal_Type);
11505 -- An access formal type
11509 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11511 -- No need to continue if we already notified errors
11513 if not Present (Formal_Type) then
11517 -- Ada 2005 (AI-254)
11520 AD : constant Node_Id :=
11521 Access_To_Subprogram_Definition
11522 (Parameter_Type (Param_Spec));
11524 if Present (AD) and then Protected_Present (AD) then
11526 Replace_Anonymous_Access_To_Protected_Subprogram
11532 Set_Etype (Formal, Formal_Type);
11534 -- Deal with default expression if present
11536 Default := Expression (Param_Spec);
11538 if Present (Default) then
11539 Check_SPARK_05_Restriction
11540 ("default expression is not allowed", Default);
11542 if Out_Present (Param_Spec) then
11544 ("default initialization only allowed for IN parameters",
11548 -- Do the special preanalysis of the expression (see section on
11549 -- "Handling of Default Expressions" in the spec of package Sem).
11551 Preanalyze_Formal_Expression (Default, Formal_Type);
11553 -- An access to constant cannot be the default for
11554 -- an access parameter that is an access to variable.
11556 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11557 and then not Is_Access_Constant (Formal_Type)
11558 and then Is_Access_Type (Etype (Default))
11559 and then Is_Access_Constant (Etype (Default))
11562 ("formal that is access to variable cannot be initialized "
11563 & "with an access-to-constant expression", Default);
11566 -- Check that the designated type of an access parameter's default
11567 -- is not a class-wide type unless the parameter's designated type
11568 -- is also class-wide.
11570 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11571 and then not Designates_From_Limited_With (Formal_Type)
11572 and then Is_Class_Wide_Default (Default)
11573 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11576 ("access to class-wide expression not allowed here", Default);
11579 -- Check incorrect use of dynamically tagged expressions
11581 if Is_Tagged_Type (Formal_Type) then
11582 Check_Dynamically_Tagged_Expression
11584 Typ => Formal_Type,
11585 Related_Nod => Default);
11589 -- Ada 2005 (AI-231): Static checks
11591 if Ada_Version >= Ada_2005
11592 and then Is_Access_Type (Etype (Formal))
11593 and then Can_Never_Be_Null (Etype (Formal))
11595 Null_Exclusion_Static_Checks (Param_Spec);
11598 -- The following checks are relevant only when SPARK_Mode is on as
11599 -- these are not standard Ada legality rules.
11601 if SPARK_Mode = On then
11602 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11604 -- A function cannot have a parameter of mode IN OUT or OUT
11607 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11609 ("function cannot have parameter of mode `OUT` or "
11610 & "`IN OUT`", Formal);
11613 -- A procedure cannot have an effectively volatile formal
11614 -- parameter of mode IN because it behaves as a constant
11615 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11617 elsif Ekind (Scope (Formal)) = E_Procedure
11618 and then Ekind (Formal) = E_In_Parameter
11619 and then Is_Effectively_Volatile (Formal)
11622 ("formal parameter of mode `IN` cannot be volatile", Formal);
11630 -- If this is the formal part of a function specification, analyze the
11631 -- subtype mark in the context where the formals are visible but not
11632 -- yet usable, and may hide outer homographs.
11634 if Nkind (Related_Nod) = N_Function_Specification then
11635 Analyze_Return_Type (Related_Nod);
11638 -- Now set the kind (mode) of each formal
11640 Param_Spec := First (T);
11641 while Present (Param_Spec) loop
11642 Formal := Defining_Identifier (Param_Spec);
11643 Set_Formal_Mode (Formal);
11645 if Ekind (Formal) = E_In_Parameter then
11646 Set_Default_Value (Formal, Expression (Param_Spec));
11648 if Present (Expression (Param_Spec)) then
11649 Default := Expression (Param_Spec);
11651 if Is_Scalar_Type (Etype (Default)) then
11652 if Nkind (Parameter_Type (Param_Spec)) /=
11653 N_Access_Definition
11655 Formal_Type := Entity (Parameter_Type (Param_Spec));
11659 (Related_Nod, Parameter_Type (Param_Spec));
11662 Apply_Scalar_Range_Check (Default, Formal_Type);
11666 elsif Ekind (Formal) = E_Out_Parameter then
11667 Num_Out_Params := Num_Out_Params + 1;
11669 if Num_Out_Params = 1 then
11670 First_Out_Param := Formal;
11673 elsif Ekind (Formal) = E_In_Out_Parameter then
11674 Num_Out_Params := Num_Out_Params + 1;
11677 -- Skip remaining processing if formal type was in error
11679 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11680 goto Next_Parameter;
11683 -- Force call by reference if aliased
11686 Conv : constant Convention_Id := Convention (Etype (Formal));
11688 if Is_Aliased (Formal) then
11689 Set_Mechanism (Formal, By_Reference);
11691 -- Warn if user asked this to be passed by copy
11693 if Conv = Convention_Ada_Pass_By_Copy then
11695 ("cannot pass aliased parameter & by copy??", Formal);
11698 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11700 elsif Conv = Convention_Ada_Pass_By_Copy then
11701 Set_Mechanism (Formal, By_Copy);
11703 elsif Conv = Convention_Ada_Pass_By_Reference then
11704 Set_Mechanism (Formal, By_Reference);
11712 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11713 Set_Is_Only_Out_Parameter (First_Out_Param);
11715 end Process_Formals;
11717 ----------------------------
11718 -- Reference_Body_Formals --
11719 ----------------------------
11721 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11726 if Error_Posted (Spec) then
11730 -- Iterate over both lists. They may be of different lengths if the two
11731 -- specs are not conformant.
11733 Fs := First_Formal (Spec);
11734 Fb := First_Formal (Bod);
11735 while Present (Fs) and then Present (Fb) loop
11736 Generate_Reference (Fs, Fb, 'b');
11738 if Style_Check then
11739 Style.Check_Identifier (Fb, Fs);
11742 Set_Spec_Entity (Fb, Fs);
11743 Set_Referenced (Fs, False);
11747 end Reference_Body_Formals;
11749 -------------------------
11750 -- Set_Actual_Subtypes --
11751 -------------------------
11753 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11755 Formal : Entity_Id;
11757 First_Stmt : Node_Id := Empty;
11758 AS_Needed : Boolean;
11761 -- If this is an empty initialization procedure, no need to create
11762 -- actual subtypes (small optimization).
11764 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11767 -- Within a predicate function we do not want to generate local
11768 -- subtypes that may generate nested predicate functions.
11770 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11774 -- The subtype declarations may freeze the formals. The body generated
11775 -- for an expression function is not a freeze point, so do not emit
11776 -- these declarations (small loss of efficiency in rare cases).
11778 if Nkind (N) = N_Subprogram_Body
11779 and then Was_Expression_Function (N)
11784 Formal := First_Formal (Subp);
11785 while Present (Formal) loop
11786 T := Etype (Formal);
11788 -- We never need an actual subtype for a constrained formal
11790 if Is_Constrained (T) then
11791 AS_Needed := False;
11793 -- If we have unknown discriminants, then we do not need an actual
11794 -- subtype, or more accurately we cannot figure it out. Note that
11795 -- all class-wide types have unknown discriminants.
11797 elsif Has_Unknown_Discriminants (T) then
11798 AS_Needed := False;
11800 -- At this stage we have an unconstrained type that may need an
11801 -- actual subtype. For sure the actual subtype is needed if we have
11802 -- an unconstrained array type. However, in an instance, the type
11803 -- may appear as a subtype of the full view, while the actual is
11804 -- in fact private (in which case no actual subtype is needed) so
11805 -- check the kind of the base type.
11807 elsif Is_Array_Type (Base_Type (T)) then
11810 -- The only other case needing an actual subtype is an unconstrained
11811 -- record type which is an IN parameter (we cannot generate actual
11812 -- subtypes for the OUT or IN OUT case, since an assignment can
11813 -- change the discriminant values. However we exclude the case of
11814 -- initialization procedures, since discriminants are handled very
11815 -- specially in this context, see the section entitled "Handling of
11816 -- Discriminants" in Einfo.
11818 -- We also exclude the case of Discrim_SO_Functions (functions used
11819 -- in front-end layout mode for size/offset values), since in such
11820 -- functions only discriminants are referenced, and not only are such
11821 -- subtypes not needed, but they cannot always be generated, because
11822 -- of order of elaboration issues.
11824 elsif Is_Record_Type (T)
11825 and then Ekind (Formal) = E_In_Parameter
11826 and then Chars (Formal) /= Name_uInit
11827 and then not Is_Unchecked_Union (T)
11828 and then not Is_Discrim_SO_Function (Subp)
11832 -- All other cases do not need an actual subtype
11835 AS_Needed := False;
11838 -- Generate actual subtypes for unconstrained arrays and
11839 -- unconstrained discriminated records.
11842 if Nkind (N) = N_Accept_Statement then
11844 -- If expansion is active, the formal is replaced by a local
11845 -- variable that renames the corresponding entry of the
11846 -- parameter block, and it is this local variable that may
11847 -- require an actual subtype.
11849 if Expander_Active then
11850 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11852 Decl := Build_Actual_Subtype (T, Formal);
11855 if Present (Handled_Statement_Sequence (N)) then
11857 First (Statements (Handled_Statement_Sequence (N)));
11858 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11859 Mark_Rewrite_Insertion (Decl);
11861 -- If the accept statement has no body, there will be no
11862 -- reference to the actuals, so no need to compute actual
11869 Decl := Build_Actual_Subtype (T, Formal);
11870 Prepend (Decl, Declarations (N));
11871 Mark_Rewrite_Insertion (Decl);
11874 -- The declaration uses the bounds of an existing object, and
11875 -- therefore needs no constraint checks.
11877 Analyze (Decl, Suppress => All_Checks);
11878 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11880 -- We need to freeze manually the generated type when it is
11881 -- inserted anywhere else than in a declarative part.
11883 if Present (First_Stmt) then
11884 Insert_List_Before_And_Analyze (First_Stmt,
11885 Freeze_Entity (Defining_Identifier (Decl), N));
11887 -- Ditto if the type has a dynamic predicate, because the
11888 -- generated function will mention the actual subtype. The
11889 -- predicate may come from an explicit aspect of be inherited.
11891 elsif Has_Predicates (T) then
11892 Insert_List_Before_And_Analyze (Decl,
11893 Freeze_Entity (Defining_Identifier (Decl), N));
11896 if Nkind (N) = N_Accept_Statement
11897 and then Expander_Active
11899 Set_Actual_Subtype (Renamed_Object (Formal),
11900 Defining_Identifier (Decl));
11902 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11906 Next_Formal (Formal);
11908 end Set_Actual_Subtypes;
11910 ---------------------
11911 -- Set_Formal_Mode --
11912 ---------------------
11914 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11915 Spec : constant Node_Id := Parent (Formal_Id);
11916 Id : constant Entity_Id := Scope (Formal_Id);
11919 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11920 -- since we ensure that corresponding actuals are always valid at the
11921 -- point of the call.
11923 if Out_Present (Spec) then
11924 if Ekind_In (Id, E_Entry, E_Entry_Family)
11925 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11927 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11930 if Ekind_In (Id, E_Function, E_Generic_Function) then
11932 -- [IN] OUT parameters allowed for functions in Ada 2012
11934 if Ada_Version >= Ada_2012 then
11936 -- Even in Ada 2012 operators can only have IN parameters
11938 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11939 Error_Msg_N ("operators can only have IN parameters", Spec);
11942 if In_Present (Spec) then
11943 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11945 Set_Ekind (Formal_Id, E_Out_Parameter);
11948 -- But not in earlier versions of Ada
11951 Error_Msg_N ("functions can only have IN parameters", Spec);
11952 Set_Ekind (Formal_Id, E_In_Parameter);
11955 elsif In_Present (Spec) then
11956 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11959 Set_Ekind (Formal_Id, E_Out_Parameter);
11960 Set_Never_Set_In_Source (Formal_Id, True);
11961 Set_Is_True_Constant (Formal_Id, False);
11962 Set_Current_Value (Formal_Id, Empty);
11966 Set_Ekind (Formal_Id, E_In_Parameter);
11969 -- Set Is_Known_Non_Null for access parameters since the language
11970 -- guarantees that access parameters are always non-null. We also set
11971 -- Can_Never_Be_Null, since there is no way to change the value.
11973 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11975 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11976 -- null; In Ada 2005, only if then null_exclusion is explicit.
11978 if Ada_Version < Ada_2005
11979 or else Can_Never_Be_Null (Etype (Formal_Id))
11981 Set_Is_Known_Non_Null (Formal_Id);
11982 Set_Can_Never_Be_Null (Formal_Id);
11985 -- Ada 2005 (AI-231): Null-exclusion access subtype
11987 elsif Is_Access_Type (Etype (Formal_Id))
11988 and then Can_Never_Be_Null (Etype (Formal_Id))
11990 Set_Is_Known_Non_Null (Formal_Id);
11992 -- We can also set Can_Never_Be_Null (thus preventing some junk
11993 -- access checks) for the case of an IN parameter, which cannot
11994 -- be changed, or for an IN OUT parameter, which can be changed but
11995 -- not to a null value. But for an OUT parameter, the initial value
11996 -- passed in can be null, so we can't set this flag in that case.
11998 if Ekind (Formal_Id) /= E_Out_Parameter then
11999 Set_Can_Never_Be_Null (Formal_Id);
12003 Set_Mechanism (Formal_Id, Default_Mechanism);
12004 Set_Formal_Validity (Formal_Id);
12005 end Set_Formal_Mode;
12007 -------------------------
12008 -- Set_Formal_Validity --
12009 -------------------------
12011 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12013 -- If no validity checking, then we cannot assume anything about the
12014 -- validity of parameters, since we do not know there is any checking
12015 -- of the validity on the call side.
12017 if not Validity_Checks_On then
12020 -- If validity checking for parameters is enabled, this means we are
12021 -- not supposed to make any assumptions about argument values.
12023 elsif Validity_Check_Parameters then
12026 -- If we are checking in parameters, we will assume that the caller is
12027 -- also checking parameters, so we can assume the parameter is valid.
12029 elsif Ekind (Formal_Id) = E_In_Parameter
12030 and then Validity_Check_In_Params
12032 Set_Is_Known_Valid (Formal_Id, True);
12034 -- Similar treatment for IN OUT parameters
12036 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12037 and then Validity_Check_In_Out_Params
12039 Set_Is_Known_Valid (Formal_Id, True);
12041 end Set_Formal_Validity;
12043 ------------------------
12044 -- Subtype_Conformant --
12045 ------------------------
12047 function Subtype_Conformant
12048 (New_Id : Entity_Id;
12049 Old_Id : Entity_Id;
12050 Skip_Controlling_Formals : Boolean := False) return Boolean
12054 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12055 Skip_Controlling_Formals => Skip_Controlling_Formals);
12057 end Subtype_Conformant;
12059 ---------------------
12060 -- Type_Conformant --
12061 ---------------------
12063 function Type_Conformant
12064 (New_Id : Entity_Id;
12065 Old_Id : Entity_Id;
12066 Skip_Controlling_Formals : Boolean := False) return Boolean
12070 May_Hide_Profile := False;
12072 (New_Id, Old_Id, Type_Conformant, False, Result,
12073 Skip_Controlling_Formals => Skip_Controlling_Formals);
12075 end Type_Conformant;
12077 -------------------------------
12078 -- Valid_Operator_Definition --
12079 -------------------------------
12081 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12084 Id : constant Name_Id := Chars (Designator);
12088 F := First_Formal (Designator);
12089 while Present (F) loop
12092 if Present (Default_Value (F)) then
12094 ("default values not allowed for operator parameters",
12097 -- For function instantiations that are operators, we must check
12098 -- separately that the corresponding generic only has in-parameters.
12099 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12100 -- an error could not arise in earlier versions of the language.
12102 elsif Ekind (F) /= E_In_Parameter then
12103 Error_Msg_N ("operators can only have IN parameters", F);
12109 -- Verify that user-defined operators have proper number of arguments
12110 -- First case of operators which can only be unary
12112 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12115 -- Case of operators which can be unary or binary
12117 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12118 N_OK := (N in 1 .. 2);
12120 -- All other operators can only be binary
12128 ("incorrect number of arguments for operator", Designator);
12132 and then Base_Type (Etype (Designator)) = Standard_Boolean
12133 and then not Is_Intrinsic_Subprogram (Designator)
12136 ("explicit definition of inequality not allowed", Designator);
12138 end Valid_Operator_Definition;