1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id);
210 -- Preanalysis of default expressions of subprogram formals. N is the
211 -- expression to be analyzed and T is the expected type.
213 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
214 -- Formal_Id is an formal parameter entity. This procedure deals with
215 -- setting the proper validity status for this entity, which depends on
216 -- the kind of parameter and the validity checking mode.
218 ---------------------------------------------
219 -- Analyze_Abstract_Subprogram_Declaration --
220 ---------------------------------------------
222 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
223 Scop : constant Entity_Id := Current_Scope;
224 Subp_Id : constant Entity_Id :=
225 Analyze_Subprogram_Specification (Specification (N));
228 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
230 Generate_Definition (Subp_Id);
232 -- Set the SPARK mode from the current context (may be overwritten later
233 -- with explicit pragma).
235 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
236 Set_SPARK_Pragma_Inherited (Subp_Id);
238 -- Preserve relevant elaboration-related attributes of the context which
239 -- are no longer available or very expensive to recompute once analysis,
240 -- resolution, and expansion are over.
242 Mark_Elaboration_Attributes
247 Set_Is_Abstract_Subprogram (Subp_Id);
248 New_Overloaded_Entity (Subp_Id);
249 Check_Delayed_Subprogram (Subp_Id);
251 Set_Categorization_From_Scope (Subp_Id, Scop);
253 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
254 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
256 -- Issue a warning if the abstract subprogram is neither a dispatching
257 -- operation nor an operation that overrides an inherited subprogram or
258 -- predefined operator, since this most likely indicates a mistake.
260 elsif Warn_On_Redundant_Constructs
261 and then not Is_Dispatching_Operation (Subp_Id)
262 and then not Present (Overridden_Operation (Subp_Id))
263 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
264 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
267 ("abstract subprogram is not dispatching or overriding?r?", N);
270 Generate_Reference_To_Formals (Subp_Id);
271 Check_Eliminated (Subp_Id);
273 if Has_Aspects (N) then
274 Analyze_Aspect_Specifications (N, Subp_Id);
276 end Analyze_Abstract_Subprogram_Declaration;
278 ---------------------------------
279 -- Analyze_Expression_Function --
280 ---------------------------------
282 procedure Analyze_Expression_Function (N : Node_Id) is
283 Expr : constant Node_Id := Expression (N);
284 Loc : constant Source_Ptr := Sloc (N);
285 LocX : constant Source_Ptr := Sloc (Expr);
286 Spec : constant Node_Id := Specification (N);
296 Def_Id : Entity_Id := Empty;
298 -- If the expression is a completion, Prev is the entity whose
299 -- declaration is completed. Def_Id is needed to analyze the spec.
301 -- Start of processing for Analyze_Expression_Function
304 -- This is one of the occasions on which we transform the tree during
305 -- semantic analysis. If this is a completion, transform the expression
306 -- function into an equivalent subprogram body, and analyze it.
308 -- Expression functions are inlined unconditionally. The back-end will
309 -- determine whether this is possible.
311 Inline_Processing_Required := True;
313 -- Create a specification for the generated body. This must be done
314 -- prior to the analysis of the initial declaration.
316 New_Spec := Copy_Subprogram_Spec (Spec);
317 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
319 -- If there are previous overloadable entities with the same name,
320 -- check whether any of them is completed by the expression function.
321 -- In a generic context a formal subprogram has no completion.
324 and then Is_Overloadable (Prev)
325 and then not Is_Formal_Subprogram (Prev)
327 Def_Id := Analyze_Subprogram_Specification (Spec);
328 Prev := Find_Corresponding_Spec (N);
330 -- The previous entity may be an expression function as well, in
331 -- which case the redeclaration is illegal.
334 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
335 N_Expression_Function
337 Error_Msg_Sloc := Sloc (Prev);
338 Error_Msg_N ("& conflicts with declaration#", Def_Id);
343 Ret := Make_Simple_Return_Statement (LocX, Expr);
346 Make_Subprogram_Body (Loc,
347 Specification => New_Spec,
348 Declarations => Empty_List,
349 Handled_Statement_Sequence =>
350 Make_Handled_Sequence_Of_Statements (LocX,
351 Statements => New_List (Ret)));
352 Set_Was_Expression_Function (New_Body);
354 -- If the expression completes a generic subprogram, we must create a
355 -- separate node for the body, because at instantiation the original
356 -- node of the generic copy must be a generic subprogram body, and
357 -- cannot be a expression function. Otherwise we just rewrite the
358 -- expression with the non-generic body.
360 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
361 Insert_After (N, New_Body);
363 -- Propagate any aspects or pragmas that apply to the expression
364 -- function to the proper body when the expression function acts
367 if Has_Aspects (N) then
368 Move_Aspects (N, To => New_Body);
371 Relocate_Pragmas_To_Body (New_Body);
373 Rewrite (N, Make_Null_Statement (Loc));
374 Set_Has_Completion (Prev, False);
377 Set_Is_Inlined (Prev);
379 -- If the expression function is a completion, the previous declaration
380 -- must come from source. We know already that it appears in the current
381 -- scope. The entity itself may be internally created if within a body
385 and then Is_Overloadable (Prev)
386 and then not Is_Formal_Subprogram (Prev)
387 and then Comes_From_Source (Parent (Prev))
389 Set_Has_Completion (Prev, False);
390 Set_Is_Inlined (Prev);
392 -- AI12-0103: Expression functions that are a completion freeze their
393 -- expression but don't freeze anything else (unlike regular bodies).
395 -- Note that we cannot defer this freezing to the analysis of the
396 -- expression itself, because a freeze node might appear in a nested
397 -- scope, leading to an elaboration order issue in gigi.
398 -- As elsewhere, we do not emit freeze nodes within a generic unit.
400 if not Inside_A_Generic then
403 Typ => Etype (Def_Id),
408 -- For navigation purposes, indicate that the function is a body
410 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
411 Rewrite (N, New_Body);
413 -- Remove any existing aspects from the original node because the act
414 -- of rewriting causes the list to be shared between the two nodes.
416 Orig_N := Original_Node (N);
417 Remove_Aspects (Orig_N);
419 -- Propagate any pragmas that apply to expression function to the
420 -- proper body when the expression function acts as a completion.
421 -- Aspects are automatically transfered because of node rewriting.
423 Relocate_Pragmas_To_Body (N);
426 -- Once the aspects of the generated body have been analyzed, create
427 -- a copy for ASIS purposes and associate it with the original node.
429 if Has_Aspects (N) then
430 Set_Aspect_Specifications (Orig_N,
431 New_Copy_List_Tree (Aspect_Specifications (N)));
434 -- Prev is the previous entity with the same name, but it is can
435 -- be an unrelated spec that is not completed by the expression
436 -- function. In that case the relevant entity is the one in the body.
437 -- Not clear that the backend can inline it in this case ???
439 if Has_Completion (Prev) then
441 -- The formals of the expression function are body formals,
442 -- and do not appear in the ali file, which will only contain
443 -- references to the formals of the original subprogram spec.
450 F1 := First_Formal (Def_Id);
451 F2 := First_Formal (Prev);
453 while Present (F1) loop
454 Set_Spec_Entity (F1, F2);
461 Set_Is_Inlined (Defining_Entity (New_Body));
464 -- If this is not a completion, create both a declaration and a body, so
465 -- that the expression can be inlined whenever possible.
468 -- An expression function that is not a completion is not a
469 -- subprogram declaration, and thus cannot appear in a protected
472 if Nkind (Parent (N)) = N_Protected_Definition then
474 ("an expression function is not a legal protected operation", N);
477 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
479 -- Remove any existing aspects from the original node because the act
480 -- of rewriting causes the list to be shared between the two nodes.
482 Orig_N := Original_Node (N);
483 Remove_Aspects (Orig_N);
487 -- Once the aspects of the generated spec have been analyzed, create
488 -- a copy for ASIS purposes and associate it with the original node.
490 if Has_Aspects (N) then
491 Set_Aspect_Specifications (Orig_N,
492 New_Copy_List_Tree (Aspect_Specifications (N)));
495 -- If aspect SPARK_Mode was specified on the body, it needs to be
496 -- repeated both on the generated spec and the body.
498 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
500 if Present (Asp) then
501 Asp := New_Copy_Tree (Asp);
502 Set_Analyzed (Asp, False);
503 Set_Aspect_Specifications (New_Body, New_List (Asp));
506 Def_Id := Defining_Entity (N);
507 Set_Is_Inlined (Def_Id);
509 -- Establish the linkages between the spec and the body. These are
510 -- used when the expression function acts as the prefix of attribute
511 -- 'Access in order to freeze the original expression which has been
512 -- moved to the generated body.
514 Set_Corresponding_Body (N, Defining_Entity (New_Body));
515 Set_Corresponding_Spec (New_Body, Def_Id);
517 -- Within a generic preanalyze the original expression for name
518 -- capture. The body is also generated but plays no role in
519 -- this because it is not part of the original source.
521 if Inside_A_Generic then
522 Set_Has_Completion (Def_Id);
524 Install_Formals (Def_Id);
525 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
529 -- To prevent premature freeze action, insert the new body at the end
530 -- of the current declarations, or at the end of the package spec.
531 -- However, resolve usage names now, to prevent spurious visibility
532 -- on later entities. Note that the function can now be called in
533 -- the current declarative part, which will appear to be prior to
534 -- the presence of the body in the code. There are nevertheless no
535 -- order of elaboration issues because all name resolution has taken
536 -- place at the point of declaration.
539 Decls : List_Id := List_Containing (N);
540 Expr : constant Node_Id := Expression (Ret);
541 Par : constant Node_Id := Parent (Decls);
542 Typ : constant Entity_Id := Etype (Def_Id);
545 -- If this is a wrapper created for in an instance for a formal
546 -- subprogram, insert body after declaration, to be analyzed when
547 -- the enclosing instance is analyzed.
550 and then Is_Generic_Actual_Subprogram (Def_Id)
552 Insert_After (N, New_Body);
555 if Nkind (Par) = N_Package_Specification
556 and then Decls = Visible_Declarations (Par)
557 and then Present (Private_Declarations (Par))
558 and then not Is_Empty_List (Private_Declarations (Par))
560 Decls := Private_Declarations (Par);
563 Insert_After (Last (Decls), New_Body);
565 -- Preanalyze the expression if not already done above
567 if not Inside_A_Generic then
569 Install_Formals (Def_Id);
570 Preanalyze_Formal_Expression (Expr, Typ);
571 Check_Limited_Return (Original_Node (N), Expr, Typ);
578 -- Check incorrect use of dynamically tagged expression. This doesn't
579 -- fall out automatically when analyzing the generated function body,
580 -- because Check_Dynamically_Tagged_Expression deliberately ignores
581 -- nodes that don't come from source.
584 and then Nkind (Def_Id) in N_Has_Etype
585 and then Is_Tagged_Type (Etype (Def_Id))
587 Check_Dynamically_Tagged_Expression
589 Typ => Etype (Def_Id),
590 Related_Nod => Original_Node (N));
593 -- We must enforce checks for unreferenced formals in our newly
594 -- generated function, so we propagate the referenced flag from the
595 -- original spec to the new spec as well as setting Comes_From_Source.
597 if Present (Parameter_Specifications (New_Spec)) then
599 Form_New_Def : Entity_Id;
600 Form_New_Spec : Entity_Id;
601 Form_Old_Def : Entity_Id;
602 Form_Old_Spec : Entity_Id;
605 Form_New_Spec := First (Parameter_Specifications (New_Spec));
606 Form_Old_Spec := First (Parameter_Specifications (Spec));
608 while Present (Form_New_Spec) and then Present (Form_Old_Spec) loop
609 Form_New_Def := Defining_Identifier (Form_New_Spec);
610 Form_Old_Def := Defining_Identifier (Form_Old_Spec);
612 Set_Comes_From_Source (Form_New_Def, True);
614 -- Because of the usefulness of unreferenced controlling
615 -- formals we exempt them from unreferenced warnings by marking
616 -- them as always referenced.
618 Set_Referenced (Form_Old_Def,
619 (Is_Formal (Form_Old_Def)
620 and then Is_Controlling_Formal (Form_Old_Def))
621 or else Referenced (Form_Old_Def));
623 Next (Form_New_Spec);
624 Next (Form_Old_Spec);
628 end Analyze_Expression_Function;
630 ----------------------------------------
631 -- Analyze_Extended_Return_Statement --
632 ----------------------------------------
634 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
636 Check_Compiler_Unit ("extended return statement", N);
637 Analyze_Return_Statement (N);
638 end Analyze_Extended_Return_Statement;
640 ----------------------------
641 -- Analyze_Function_Call --
642 ----------------------------
644 procedure Analyze_Function_Call (N : Node_Id) is
645 Actuals : constant List_Id := Parameter_Associations (N);
646 Func_Nam : constant Node_Id := Name (N);
652 -- A call of the form A.B (X) may be an Ada 2005 call, which is
653 -- rewritten as B (A, X). If the rewriting is successful, the call
654 -- has been analyzed and we just return.
656 if Nkind (Func_Nam) = N_Selected_Component
657 and then Name (N) /= Func_Nam
658 and then Is_Rewrite_Substitution (N)
659 and then Present (Etype (N))
664 -- If error analyzing name, then set Any_Type as result type and return
666 if Etype (Func_Nam) = Any_Type then
667 Set_Etype (N, Any_Type);
671 -- Otherwise analyze the parameters
673 if Present (Actuals) then
674 Actual := First (Actuals);
675 while Present (Actual) loop
677 Check_Parameterless_Call (Actual);
683 end Analyze_Function_Call;
685 -----------------------------
686 -- Analyze_Function_Return --
687 -----------------------------
689 procedure Analyze_Function_Return (N : Node_Id) is
690 Loc : constant Source_Ptr := Sloc (N);
691 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
692 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
694 R_Type : constant Entity_Id := Etype (Scope_Id);
695 -- Function result subtype
697 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
698 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
699 -- aggregate in a return statement.
701 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
702 -- Check that the return_subtype_indication properly matches the result
703 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
705 -----------------------------------
706 -- Check_Aggregate_Accessibility --
707 -----------------------------------
709 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
710 Typ : constant Entity_Id := Etype (Aggr);
717 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
718 Discr := First_Discriminant (Typ);
719 Assoc := First (Component_Associations (Aggr));
720 while Present (Discr) loop
721 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
722 Expr := Expression (Assoc);
724 if Nkind (Expr) = N_Attribute_Reference
725 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
727 Obj := Prefix (Expr);
728 while Nkind_In (Obj, N_Indexed_Component,
729 N_Selected_Component)
734 -- Do not check aliased formals or function calls. A
735 -- run-time check may still be needed ???
737 if Is_Entity_Name (Obj)
738 and then Comes_From_Source (Obj)
740 if Is_Formal (Entity (Obj))
741 and then Is_Aliased (Entity (Obj))
745 elsif Object_Access_Level (Obj) >
746 Scope_Depth (Scope (Scope_Id))
749 ("access discriminant in return aggregate would "
750 & "be a dangling reference", Obj);
756 Next_Discriminant (Discr);
759 end Check_Aggregate_Accessibility;
761 -------------------------------------
762 -- Check_Return_Subtype_Indication --
763 -------------------------------------
765 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
766 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
768 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
769 -- Subtype given in the extended return statement (must match R_Type)
771 Subtype_Ind : constant Node_Id :=
772 Object_Definition (Original_Node (Obj_Decl));
774 procedure Error_No_Match (N : Node_Id);
775 -- Output error messages for case where types do not statically
776 -- match. N is the location for the messages.
782 procedure Error_No_Match (N : Node_Id) is
785 ("subtype must statically match function result subtype", N);
787 if not Predicates_Match (R_Stm_Type, R_Type) then
788 Error_Msg_Node_2 := R_Type;
790 ("\predicate of& does not match predicate of&",
795 -- Start of processing for Check_Return_Subtype_Indication
798 -- First, avoid cascaded errors
800 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
804 -- "return access T" case; check that the return statement also has
805 -- "access T", and that the subtypes statically match:
806 -- if this is an access to subprogram the signatures must match.
808 if Is_Anonymous_Access_Type (R_Type) then
809 if Is_Anonymous_Access_Type (R_Stm_Type) then
810 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
812 if Base_Type (Designated_Type (R_Stm_Type)) /=
813 Base_Type (Designated_Type (R_Type))
814 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
816 Error_No_Match (Subtype_Mark (Subtype_Ind));
820 -- For two anonymous access to subprogram types, the types
821 -- themselves must be type conformant.
823 if not Conforming_Types
824 (R_Stm_Type, R_Type, Fully_Conformant)
826 Error_No_Match (Subtype_Ind);
831 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
834 -- If the return object is of an anonymous access type, then report
835 -- an error if the function's result type is not also anonymous.
837 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
838 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
840 ("anonymous access not allowed for function with named access "
841 & "result", Subtype_Ind);
843 -- Subtype indication case: check that the return object's type is
844 -- covered by the result type, and that the subtypes statically match
845 -- when the result subtype is constrained. Also handle record types
846 -- with unknown discriminants for which we have built the underlying
847 -- record view. Coverage is needed to allow specific-type return
848 -- objects when the result type is class-wide (see AI05-32).
850 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
851 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
855 Underlying_Record_View (Base_Type (R_Stm_Type))))
857 -- A null exclusion may be present on the return type, on the
858 -- function specification, on the object declaration or on the
861 if Is_Access_Type (R_Type)
863 (Can_Never_Be_Null (R_Type)
864 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
865 Can_Never_Be_Null (R_Stm_Type)
867 Error_No_Match (Subtype_Ind);
870 -- AI05-103: for elementary types, subtypes must statically match
872 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
873 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
874 Error_No_Match (Subtype_Ind);
878 -- All remaining cases are illegal
880 -- Note: previous versions of this subprogram allowed the return
881 -- value to be the ancestor of the return type if the return type
882 -- was a null extension. This was plainly incorrect.
886 ("wrong type for return_subtype_indication", Subtype_Ind);
888 end Check_Return_Subtype_Indication;
890 ---------------------
891 -- Local Variables --
892 ---------------------
895 Obj_Decl : Node_Id := Empty;
897 -- Start of processing for Analyze_Function_Return
900 Set_Return_Present (Scope_Id);
902 if Nkind (N) = N_Simple_Return_Statement then
903 Expr := Expression (N);
905 -- Guard against a malformed expression. The parser may have tried to
906 -- recover but the node is not analyzable.
908 if Nkind (Expr) = N_Error then
909 Set_Etype (Expr, Any_Type);
910 Expander_Mode_Save_And_Set (False);
914 -- The resolution of a controlled [extension] aggregate associated
915 -- with a return statement creates a temporary which needs to be
916 -- finalized on function exit. Wrap the return statement inside a
917 -- block so that the finalization machinery can detect this case.
918 -- This early expansion is done only when the return statement is
919 -- not part of a handled sequence of statements.
921 if Nkind_In (Expr, N_Aggregate,
922 N_Extension_Aggregate)
923 and then Needs_Finalization (R_Type)
924 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
927 Make_Block_Statement (Loc,
928 Handled_Statement_Sequence =>
929 Make_Handled_Sequence_Of_Statements (Loc,
930 Statements => New_List (Relocate_Node (N)))));
938 -- Ada 2005 (AI-251): If the type of the returned object is
939 -- an access to an interface type then we add an implicit type
940 -- conversion to force the displacement of the "this" pointer to
941 -- reference the secondary dispatch table. We cannot delay the
942 -- generation of this implicit conversion until the expansion
943 -- because in this case the type resolution changes the decoration
944 -- of the expression node to match R_Type; by contrast, if the
945 -- returned object is a class-wide interface type then it is too
946 -- early to generate here the implicit conversion since the return
947 -- statement may be rewritten by the expander into an extended
948 -- return statement whose expansion takes care of adding the
949 -- implicit type conversion to displace the pointer to the object.
952 and then Serious_Errors_Detected = 0
953 and then Is_Access_Type (R_Type)
954 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
955 and then Is_Interface (Designated_Type (R_Type))
956 and then Is_Progenitor (Designated_Type (R_Type),
957 Designated_Type (Etype (Expr)))
959 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
963 Resolve (Expr, R_Type);
964 Check_Limited_Return (N, Expr, R_Type);
966 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
967 Check_Aggregate_Accessibility (Expr);
971 -- RETURN only allowed in SPARK as the last statement in function
973 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
975 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
976 or else Present (Next (N)))
978 Check_SPARK_05_Restriction
979 ("RETURN should be the last statement in function", N);
983 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
984 Obj_Decl := Last (Return_Object_Declarations (N));
986 -- Analyze parts specific to extended_return_statement:
989 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
990 HSS : constant Node_Id := Handled_Statement_Sequence (N);
993 Expr := Expression (Obj_Decl);
995 -- Note: The check for OK_For_Limited_Init will happen in
996 -- Analyze_Object_Declaration; we treat it as a normal
997 -- object declaration.
999 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1002 Check_Return_Subtype_Indication (Obj_Decl);
1004 if Present (HSS) then
1007 if Present (Exception_Handlers (HSS)) then
1009 -- ???Has_Nested_Block_With_Handler needs to be set.
1010 -- Probably by creating an actual N_Block_Statement.
1011 -- Probably in Expand.
1017 -- Mark the return object as referenced, since the return is an
1018 -- implicit reference of the object.
1020 Set_Referenced (Defining_Identifier (Obj_Decl));
1022 Check_References (Stm_Entity);
1024 -- Check RM 6.5 (5.9/3)
1027 if Ada_Version < Ada_2012 then
1029 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1030 -- Can it really happen (extended return???)
1033 ("aliased only allowed for limited return objects "
1034 & "in Ada 2012??", N);
1036 elsif not Is_Limited_View (R_Type) then
1038 ("aliased only allowed for limited return objects", N);
1044 -- Case of Expr present
1046 if Present (Expr) then
1048 -- Defend against previous errors
1050 if Nkind (Expr) = N_Empty
1051 or else No (Etype (Expr))
1056 -- Apply constraint check. Note that this is done before the implicit
1057 -- conversion of the expression done for anonymous access types to
1058 -- ensure correct generation of the null-excluding check associated
1059 -- with null-excluding expressions found in return statements.
1061 Apply_Constraint_Check (Expr, R_Type);
1063 -- The return value is converted to the return type of the function,
1064 -- which implies a predicate check if the return type is predicated.
1065 -- We do not apply the check to a case expression because it will
1066 -- be expanded into a series of return statements, each of which
1067 -- will receive a predicate check.
1069 if Nkind (Expr) /= N_Case_Expression then
1070 Apply_Predicate_Check (Expr, R_Type);
1073 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1074 -- type, apply an implicit conversion of the expression to that type
1075 -- to force appropriate static and run-time accessibility checks.
1077 if Ada_Version >= Ada_2005
1078 and then Ekind (R_Type) = E_Anonymous_Access_Type
1080 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1081 Analyze_And_Resolve (Expr, R_Type);
1083 -- If this is a local anonymous access to subprogram, the
1084 -- accessibility check can be applied statically. The return is
1085 -- illegal if the access type of the return expression is declared
1086 -- inside of the subprogram (except if it is the subtype indication
1087 -- of an extended return statement).
1089 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1090 if not Comes_From_Source (Current_Scope)
1091 or else Ekind (Current_Scope) = E_Return_Statement
1096 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1098 Error_Msg_N ("cannot return local access to subprogram", N);
1101 -- The expression cannot be of a formal incomplete type
1103 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1104 and then Is_Generic_Type (Etype (Expr))
1107 ("cannot return expression of a formal incomplete type", N);
1110 -- If the result type is class-wide, then check that the return
1111 -- expression's type is not declared at a deeper level than the
1112 -- function (RM05-6.5(5.6/2)).
1114 if Ada_Version >= Ada_2005
1115 and then Is_Class_Wide_Type (R_Type)
1117 if Type_Access_Level (Etype (Expr)) >
1118 Subprogram_Access_Level (Scope_Id)
1121 ("level of return expression type is deeper than "
1122 & "class-wide function!", Expr);
1126 -- Check incorrect use of dynamically tagged expression
1128 if Is_Tagged_Type (R_Type) then
1129 Check_Dynamically_Tagged_Expression
1135 -- ??? A real run-time accessibility check is needed in cases
1136 -- involving dereferences of access parameters. For now we just
1137 -- check the static cases.
1139 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1140 and then Is_Limited_View (Etype (Scope_Id))
1141 and then Object_Access_Level (Expr) >
1142 Subprogram_Access_Level (Scope_Id)
1144 -- Suppress the message in a generic, where the rewriting
1147 if Inside_A_Generic then
1152 Make_Raise_Program_Error (Loc,
1153 Reason => PE_Accessibility_Check_Failed));
1156 Error_Msg_Warn := SPARK_Mode /= On;
1157 Error_Msg_N ("cannot return a local value by reference<<", N);
1158 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1162 if Known_Null (Expr)
1163 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1164 and then Null_Exclusion_Present (Parent (Scope_Id))
1166 Apply_Compile_Time_Constraint_Error
1168 Msg => "(Ada 2005) null not allowed for "
1169 & "null-excluding return??",
1170 Reason => CE_Null_Not_Allowed);
1173 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1174 -- has no initializing expression.
1176 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1177 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1178 Subprogram_Access_Level (Scope_Id)
1181 ("level of return expression type is deeper than "
1182 & "class-wide function!", Obj_Decl);
1185 end Analyze_Function_Return;
1187 -------------------------------------
1188 -- Analyze_Generic_Subprogram_Body --
1189 -------------------------------------
1191 procedure Analyze_Generic_Subprogram_Body
1195 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1196 Kind : constant Entity_Kind := Ekind (Gen_Id);
1197 Body_Id : Entity_Id;
1202 -- Copy body and disable expansion while analyzing the generic For a
1203 -- stub, do not copy the stub (which would load the proper body), this
1204 -- will be done when the proper body is analyzed.
1206 if Nkind (N) /= N_Subprogram_Body_Stub then
1207 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1210 -- Once the contents of the generic copy and the template are
1211 -- swapped, do the same for their respective aspect specifications.
1213 Exchange_Aspects (N, New_N);
1215 -- Collect all contract-related source pragmas found within the
1216 -- template and attach them to the contract of the subprogram body.
1217 -- This contract is used in the capture of global references within
1220 Create_Generic_Contract (N);
1225 Spec := Specification (N);
1227 -- Within the body of the generic, the subprogram is callable, and
1228 -- behaves like the corresponding non-generic unit.
1230 Body_Id := Defining_Entity (Spec);
1232 if Kind = E_Generic_Procedure
1233 and then Nkind (Spec) /= N_Procedure_Specification
1235 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1238 elsif Kind = E_Generic_Function
1239 and then Nkind (Spec) /= N_Function_Specification
1241 Error_Msg_N ("invalid body for generic function ", Body_Id);
1245 Set_Corresponding_Body (Gen_Decl, Body_Id);
1247 if Has_Completion (Gen_Id)
1248 and then Nkind (Parent (N)) /= N_Subunit
1250 Error_Msg_N ("duplicate generic body", N);
1253 Set_Has_Completion (Gen_Id);
1256 if Nkind (N) = N_Subprogram_Body_Stub then
1257 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1259 Set_Corresponding_Spec (N, Gen_Id);
1262 if Nkind (Parent (N)) = N_Compilation_Unit then
1263 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1266 -- Make generic parameters immediately visible in the body. They are
1267 -- needed to process the formals declarations. Then make the formals
1268 -- visible in a separate step.
1270 Push_Scope (Gen_Id);
1274 First_Ent : Entity_Id;
1277 First_Ent := First_Entity (Gen_Id);
1280 while Present (E) and then not Is_Formal (E) loop
1285 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1287 -- Now generic formals are visible, and the specification can be
1288 -- analyzed, for subsequent conformance check.
1290 Body_Id := Analyze_Subprogram_Specification (Spec);
1292 -- Make formal parameters visible
1296 -- E is the first formal parameter, we loop through the formals
1297 -- installing them so that they will be visible.
1299 Set_First_Entity (Gen_Id, E);
1300 while Present (E) loop
1306 -- Visible generic entity is callable within its own body
1308 Set_Ekind (Gen_Id, Ekind (Body_Id));
1309 Set_Ekind (Body_Id, E_Subprogram_Body);
1310 Set_Convention (Body_Id, Convention (Gen_Id));
1311 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1312 Set_Scope (Body_Id, Scope (Gen_Id));
1314 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1316 if Nkind (N) = N_Subprogram_Body_Stub then
1318 -- No body to analyze, so restore state of generic unit
1320 Set_Ekind (Gen_Id, Kind);
1321 Set_Ekind (Body_Id, Kind);
1323 if Present (First_Ent) then
1324 Set_First_Entity (Gen_Id, First_Ent);
1331 -- If this is a compilation unit, it must be made visible explicitly,
1332 -- because the compilation of the declaration, unlike other library
1333 -- unit declarations, does not. If it is not a unit, the following
1334 -- is redundant but harmless.
1336 Set_Is_Immediately_Visible (Gen_Id);
1337 Reference_Body_Formals (Gen_Id, Body_Id);
1339 if Is_Child_Unit (Gen_Id) then
1340 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1343 Set_Actual_Subtypes (N, Current_Scope);
1345 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1346 Set_SPARK_Pragma_Inherited (Body_Id);
1348 -- Analyze any aspect specifications that appear on the generic
1351 if Has_Aspects (N) then
1352 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1355 Analyze_Declarations (Declarations (N));
1358 -- Process the contract of the subprogram body after all declarations
1359 -- have been analyzed. This ensures that any contract-related pragmas
1360 -- are available through the N_Contract node of the body.
1362 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1364 Analyze (Handled_Statement_Sequence (N));
1365 Save_Global_References (Original_Node (N));
1367 -- Prior to exiting the scope, include generic formals again (if any
1368 -- are present) in the set of local entities.
1370 if Present (First_Ent) then
1371 Set_First_Entity (Gen_Id, First_Ent);
1374 Check_References (Gen_Id);
1377 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1378 Update_Use_Clause_Chain;
1379 Validate_Categorization_Dependency (N, Gen_Id);
1381 Check_Subprogram_Order (N);
1383 -- Outside of its body, unit is generic again
1385 Set_Ekind (Gen_Id, Kind);
1386 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1389 Style.Check_Identifier (Body_Id, Gen_Id);
1393 end Analyze_Generic_Subprogram_Body;
1395 ----------------------------
1396 -- Analyze_Null_Procedure --
1397 ----------------------------
1399 -- 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_ISMP : constant Boolean :=
3374 Ignore_SPARK_Mode_Pragmas_In_Instance;
3375 -- Save the Ghost and SPARK mode-related data to restore on exit
3377 -- Start of processing for Analyze_Subprogram_Body_Helper
3380 -- A [generic] subprogram body freezes the contract of the nearest
3381 -- enclosing package body and all other contracts encountered in the
3382 -- same declarative part up to and excluding the subprogram body:
3384 -- package body Nearest_Enclosing_Package
3385 -- with Refined_State => (State => Constit)
3389 -- procedure Freezes_Enclosing_Package_Body
3390 -- with Refined_Depends => (Input => Constit) ...
3392 -- This ensures that any annotations referenced by the contract of the
3393 -- [generic] subprogram body are available. This form of freezing is
3394 -- decoupled from the usual Freeze_xxx mechanism because it must also
3395 -- work in the context of generics where normal freezing is disabled.
3397 -- Only bodies coming from source should cause this type of freezing.
3398 -- Expression functions that act as bodies and complete an initial
3399 -- declaration must be included in this category, hence the use of
3402 if Comes_From_Source (Original_Node (N)) then
3403 Freeze_Previous_Contracts (N);
3406 -- Generic subprograms are handled separately. They always have a
3407 -- generic specification. Determine whether current scope has a
3408 -- previous declaration.
3410 -- If the subprogram body is defined within an instance of the same
3411 -- name, the instance appears as a package renaming, and will be hidden
3412 -- within the subprogram.
3414 if Present (Prev_Id)
3415 and then not Is_Overloadable (Prev_Id)
3416 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3417 or else Comes_From_Source (Prev_Id))
3419 if Is_Generic_Subprogram (Prev_Id) then
3422 -- A subprogram body is Ghost when it is stand-alone and subject
3423 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3424 -- the mode now to ensure that any nodes generated during analysis
3425 -- and expansion are properly marked as Ghost.
3427 Mark_And_Set_Ghost_Body (N, Spec_Id);
3429 -- If the body completes the initial declaration of a compilation
3430 -- unit which is subject to pragma Elaboration_Checks, set the
3431 -- model specified by the pragma because it applies to all parts
3434 Install_Elaboration_Model (Spec_Id);
3436 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3437 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3439 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3441 if Nkind (N) = N_Subprogram_Body then
3442 HSS := Handled_Statement_Sequence (N);
3443 Check_Missing_Return;
3448 -- Otherwise a previous entity conflicts with the subprogram name.
3449 -- Attempting to enter name will post error.
3452 Enter_Name (Body_Id);
3456 -- Non-generic case, find the subprogram declaration, if one was seen,
3457 -- or enter new overloaded entity in the current scope. If the
3458 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3459 -- part of the context of one of its subunits. No need to redo the
3462 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3466 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3468 if Nkind (N) = N_Subprogram_Body_Stub
3469 or else No (Corresponding_Spec (N))
3471 if Is_Private_Concurrent_Primitive (Body_Id) then
3472 Spec_Id := Disambiguate_Spec;
3474 -- A subprogram body is Ghost when it is stand-alone and
3475 -- subject to pragma Ghost or when the corresponding spec is
3476 -- Ghost. Set the mode now to ensure that any nodes generated
3477 -- during analysis and expansion are properly marked as Ghost.
3479 Mark_And_Set_Ghost_Body (N, Spec_Id);
3481 -- If the body completes a compilation unit which is subject
3482 -- to pragma Elaboration_Checks, set the model specified by
3483 -- the pragma because it applies to all parts of the unit.
3485 Install_Elaboration_Model (Spec_Id);
3488 Spec_Id := Find_Corresponding_Spec (N);
3490 -- A subprogram body is Ghost when it is stand-alone and
3491 -- subject to pragma Ghost or when the corresponding spec is
3492 -- Ghost. Set the mode now to ensure that any nodes generated
3493 -- during analysis and expansion are properly marked as Ghost.
3495 Mark_And_Set_Ghost_Body (N, Spec_Id);
3497 -- If the body completes a compilation unit which is subject
3498 -- to pragma Elaboration_Checks, set the model specified by
3499 -- the pragma because it applies to all parts of the unit.
3501 Install_Elaboration_Model (Spec_Id);
3503 -- In GNATprove mode, if the body has no previous spec, create
3504 -- one so that the inlining machinery can operate properly.
3505 -- Transfer aspects, if any, to the new spec, so that they
3506 -- are legal and can be processed ahead of the body.
3507 -- We make two copies of the given spec, one for the new
3508 -- declaration, and one for the body.
3510 if No (Spec_Id) and then GNATprove_Mode
3512 -- Inlining does not apply during preanalysis of code
3514 and then Full_Analysis
3516 -- Inlining only applies to full bodies, not stubs
3518 and then Nkind (N) /= N_Subprogram_Body_Stub
3520 -- Inlining only applies to bodies in the source code, not to
3521 -- those generated by the compiler. In particular, expression
3522 -- functions, whose body is generated by the compiler, are
3523 -- treated specially by GNATprove.
3525 and then Comes_From_Source (Body_Id)
3527 -- This cannot be done for a compilation unit, which is not
3528 -- in a context where we can insert a new spec.
3530 and then Is_List_Member (N)
3532 -- Inlining only applies to subprograms without contracts,
3533 -- as a contract is a sign that GNATprove should perform a
3534 -- modular analysis of the subprogram instead of a contextual
3535 -- analysis at each call site. The same test is performed in
3536 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3537 -- here in another form (because the contract has not been
3538 -- attached to the body) to avoid front-end errors in case
3539 -- pragmas are used instead of aspects, because the
3540 -- corresponding pragmas in the body would not be transferred
3541 -- to the spec, leading to legality errors.
3543 and then not Body_Has_Contract
3544 and then not Inside_A_Generic
3546 Build_Subprogram_Declaration;
3548 -- If this is a function that returns a constrained array, and
3549 -- we are generating SPARK_For_C, create subprogram declaration
3550 -- to simplify subsequent C generation.
3553 and then Modify_Tree_For_C
3554 and then Nkind (Body_Spec) = N_Function_Specification
3555 and then Is_Array_Type (Etype (Body_Id))
3556 and then Is_Constrained (Etype (Body_Id))
3558 Build_Subprogram_Declaration;
3562 -- If this is a duplicate body, no point in analyzing it
3564 if Error_Posted (N) then
3568 -- A subprogram body should cause freezing of its own declaration,
3569 -- but if there was no previous explicit declaration, then the
3570 -- subprogram will get frozen too late (there may be code within
3571 -- the body that depends on the subprogram having been frozen,
3572 -- such as uses of extra formals), so we force it to be frozen
3573 -- here. Same holds if the body and spec are compilation units.
3574 -- Finally, if the return type is an anonymous access to protected
3575 -- subprogram, it must be frozen before the body because its
3576 -- expansion has generated an equivalent type that is used when
3577 -- elaborating the body.
3579 -- An exception in the case of Ada 2012, AI05-177: The bodies
3580 -- created for expression functions do not freeze.
3583 and then Nkind (Original_Node (N)) /= N_Expression_Function
3585 Freeze_Before (N, Body_Id);
3587 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3588 Freeze_Before (N, Spec_Id);
3590 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3591 Freeze_Before (N, Etype (Body_Id));
3595 Spec_Id := Corresponding_Spec (N);
3597 -- A subprogram body is Ghost when it is stand-alone and subject
3598 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3599 -- the mode now to ensure that any nodes generated during analysis
3600 -- and expansion are properly marked as Ghost.
3602 Mark_And_Set_Ghost_Body (N, Spec_Id);
3604 -- If the body completes the initial declaration of a compilation
3605 -- unit which is subject to pragma Elaboration_Checks, set the
3606 -- model specified by the pragma because it applies to all parts
3609 Install_Elaboration_Model (Spec_Id);
3613 -- Previously we scanned the body to look for nested subprograms, and
3614 -- rejected an inline directive if nested subprograms were present,
3615 -- because the back-end would generate conflicting symbols for the
3616 -- nested bodies. This is now unnecessary.
3618 -- Look ahead to recognize a pragma Inline that appears after the body
3620 Check_Inline_Pragma (Spec_Id);
3622 -- Deal with special case of a fully private operation in the body of
3623 -- the protected type. We must create a declaration for the subprogram,
3624 -- in order to attach the protected subprogram that will be used in
3625 -- internal calls. We exclude compiler generated bodies from the
3626 -- expander since the issue does not arise for those cases.
3629 and then Comes_From_Source (N)
3630 and then Is_Protected_Type (Current_Scope)
3632 Spec_Id := Build_Private_Protected_Declaration (N);
3635 -- If we are generating C and this is a function returning a constrained
3636 -- array type for which we must create a procedure with an extra out
3637 -- parameter, build and analyze the body now. The procedure declaration
3638 -- has already been created. We reuse the source body of the function,
3639 -- because in an instance it may contain global references that cannot
3640 -- be reanalyzed. The source function itself is not used any further,
3641 -- so we mark it as having a completion. If the subprogram is a stub the
3642 -- transformation is done later, when the proper body is analyzed.
3645 and then Modify_Tree_For_C
3646 and then Present (Spec_Id)
3647 and then Ekind (Spec_Id) = E_Function
3648 and then Nkind (N) /= N_Subprogram_Body_Stub
3649 and then Rewritten_For_C (Spec_Id)
3651 Set_Has_Completion (Spec_Id);
3653 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3656 -- The entity for the created procedure must remain invisible, so it
3657 -- does not participate in resolution of subsequent references to the
3660 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3664 -- If a separate spec is present, then deal with freezing issues
3666 if Present (Spec_Id) then
3667 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3668 Verify_Overriding_Indicator;
3670 -- In general, the spec will be frozen when we start analyzing the
3671 -- body. However, for internally generated operations, such as
3672 -- wrapper functions for inherited operations with controlling
3673 -- results, the spec may not have been frozen by the time we expand
3674 -- the freeze actions that include the bodies. In particular, extra
3675 -- formals for accessibility or for return-in-place may need to be
3676 -- generated. Freeze nodes, if any, are inserted before the current
3677 -- body. These freeze actions are also needed in ASIS mode and in
3678 -- Compile_Only mode to enable the proper back-end type annotations.
3679 -- They are necessary in any case to insure order of elaboration
3682 if Nkind (N) = N_Subprogram_Body
3683 and then Was_Expression_Function (N)
3684 and then not Has_Completion (Spec_Id)
3685 and then Serious_Errors_Detected = 0
3686 and then (Expander_Active
3688 or else Operating_Mode = Check_Semantics)
3690 -- The body generated for an expression function that is not a
3691 -- completion is a freeze point neither for the profile nor for
3692 -- anything else. That's why, in order to prevent any freezing
3693 -- during analysis, we need to mask types declared outside the
3694 -- expression (and in an outer scope) that are not yet frozen.
3696 Set_Is_Frozen (Spec_Id);
3697 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3699 elsif not Is_Frozen (Spec_Id)
3700 and then Serious_Errors_Detected = 0
3702 Set_Has_Delayed_Freeze (Spec_Id);
3703 Freeze_Before (N, Spec_Id);
3707 -- If the subprogram has a class-wide clone, build its body as a copy
3708 -- of the original body, and rewrite body of original subprogram as a
3709 -- wrapper that calls the clone. If N is a stub, this construction will
3710 -- take place when the proper body is analyzed. No action needed if this
3711 -- subprogram has been eliminated.
3713 if Present (Spec_Id)
3714 and then Present (Class_Wide_Clone (Spec_Id))
3715 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3716 and then Nkind (N) /= N_Subprogram_Body_Stub
3717 and then not (Expander_Active and then Is_Eliminated (Spec_Id))
3719 Build_Class_Wide_Clone_Body (Spec_Id, N);
3721 -- This is the new body for the existing primitive operation
3723 Rewrite (N, Build_Class_Wide_Clone_Call
3724 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3725 Set_Has_Completion (Spec_Id, False);
3730 -- Place subprogram on scope stack, and make formals visible. If there
3731 -- is a spec, the visible entity remains that of the spec.
3733 if Present (Spec_Id) then
3734 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3736 if Is_Child_Unit (Spec_Id) then
3737 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3741 Style.Check_Identifier (Body_Id, Spec_Id);
3744 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3745 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3747 if Is_Abstract_Subprogram (Spec_Id) then
3748 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3752 Set_Convention (Body_Id, Convention (Spec_Id));
3753 Set_Has_Completion (Spec_Id);
3755 if Is_Protected_Type (Scope (Spec_Id)) then
3756 Prot_Typ := Scope (Spec_Id);
3759 -- If this is a body generated for a renaming, do not check for
3760 -- full conformance. The check is redundant, because the spec of
3761 -- the body is a copy of the spec in the renaming declaration,
3762 -- and the test can lead to spurious errors on nested defaults.
3764 if Present (Spec_Decl)
3765 and then not Comes_From_Source (N)
3767 (Nkind (Original_Node (Spec_Decl)) =
3768 N_Subprogram_Renaming_Declaration
3769 or else (Present (Corresponding_Body (Spec_Decl))
3771 Nkind (Unit_Declaration_Node
3772 (Corresponding_Body (Spec_Decl))) =
3773 N_Subprogram_Renaming_Declaration))
3777 -- Conversely, the spec may have been generated for specless body
3778 -- with an inline pragma. The entity comes from source, which is
3779 -- both semantically correct and necessary for proper inlining.
3780 -- The subprogram declaration itself is not in the source.
3782 elsif Comes_From_Source (N)
3783 and then Present (Spec_Decl)
3784 and then not Comes_From_Source (Spec_Decl)
3785 and then Has_Pragma_Inline (Spec_Id)
3792 Fully_Conformant, True, Conformant, Body_Id);
3795 -- If the body is not fully conformant, we have to decide if we
3796 -- should analyze it or not. If it has a really messed up profile
3797 -- then we probably should not analyze it, since we will get too
3798 -- many bogus messages.
3800 -- Our decision is to go ahead in the non-fully conformant case
3801 -- only if it is at least mode conformant with the spec. Note
3802 -- that the call to Check_Fully_Conformant has issued the proper
3803 -- error messages to complain about the lack of conformance.
3806 and then not Mode_Conformant (Body_Id, Spec_Id)
3812 -- In the case we are dealing with an expression function we check
3813 -- the formals attached to the spec instead of the body - so we don't
3814 -- reference body formals.
3816 if Spec_Id /= Body_Id
3817 and then not Is_Expression_Function (Spec_Id)
3819 Reference_Body_Formals (Spec_Id, Body_Id);
3822 Set_Ekind (Body_Id, E_Subprogram_Body);
3824 if Nkind (N) = N_Subprogram_Body_Stub then
3825 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3830 Set_Corresponding_Spec (N, Spec_Id);
3832 -- Ada 2005 (AI-345): If the operation is a primitive operation
3833 -- of a concurrent type, the type of the first parameter has been
3834 -- replaced with the corresponding record, which is the proper
3835 -- run-time structure to use. However, within the body there may
3836 -- be uses of the formals that depend on primitive operations
3837 -- of the type (in particular calls in prefixed form) for which
3838 -- we need the original concurrent type. The operation may have
3839 -- several controlling formals, so the replacement must be done
3842 if Comes_From_Source (Spec_Id)
3843 and then Present (First_Entity (Spec_Id))
3844 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3845 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3846 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3847 and then Present (Corresponding_Concurrent_Type
3848 (Etype (First_Entity (Spec_Id))))
3851 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3855 Form := First_Formal (Spec_Id);
3856 while Present (Form) loop
3857 if Etype (Form) = Typ then
3858 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3866 -- Make the formals visible, and place subprogram on scope stack.
3867 -- This is also the point at which we set Last_Real_Spec_Entity
3868 -- to mark the entities which will not be moved to the body.
3870 Install_Formals (Spec_Id);
3871 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3873 -- Within an instance, add local renaming declarations so that
3874 -- gdb can retrieve the values of actuals more easily. This is
3875 -- only relevant if generating code (and indeed we definitely
3876 -- do not want these definitions -gnatc mode, because that would
3879 if Is_Generic_Instance (Spec_Id)
3880 and then Is_Wrapper_Package (Current_Scope)
3881 and then Expander_Active
3883 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3886 Push_Scope (Spec_Id);
3888 -- Make sure that the subprogram is immediately visible. For
3889 -- child units that have no separate spec this is indispensable.
3890 -- Otherwise it is safe albeit redundant.
3892 Set_Is_Immediately_Visible (Spec_Id);
3895 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3896 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3897 Set_Scope (Body_Id, Scope (Spec_Id));
3899 -- Case of subprogram body with no previous spec
3902 -- Check for style warning required
3906 -- Only apply check for source level subprograms for which checks
3907 -- have not been suppressed.
3909 and then Comes_From_Source (Body_Id)
3910 and then not Suppress_Style_Checks (Body_Id)
3912 -- No warnings within an instance
3914 and then not In_Instance
3916 -- No warnings for expression functions
3918 and then Nkind (Original_Node (N)) /= N_Expression_Function
3920 Style.Body_With_No_Spec (N);
3923 New_Overloaded_Entity (Body_Id);
3925 if Nkind (N) /= N_Subprogram_Body_Stub then
3926 Set_Acts_As_Spec (N);
3927 Generate_Definition (Body_Id);
3929 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3931 -- If the body is an entry wrapper created for an entry with
3932 -- preconditions, it must be compiled in the context of the
3933 -- enclosing synchronized object, because it may mention other
3934 -- operations of the type.
3936 if Is_Entry_Wrapper (Body_Id) then
3938 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3941 Install_Declarations (Prot);
3945 Install_Formals (Body_Id);
3947 Push_Scope (Body_Id);
3950 -- For stubs and bodies with no previous spec, generate references to
3953 Generate_Reference_To_Formals (Body_Id);
3956 -- Entry barrier functions are generated outside the protected type and
3957 -- should not carry the SPARK_Mode of the enclosing context.
3959 if Nkind (N) = N_Subprogram_Body
3960 and then Is_Entry_Barrier_Function (N)
3964 -- The body is generated as part of expression function expansion. When
3965 -- the expression function appears in the visible declarations of a
3966 -- package, the body is added to the private declarations. Since both
3967 -- declarative lists may be subject to a different SPARK_Mode, inherit
3968 -- the mode of the spec.
3970 -- package P with SPARK_Mode is
3971 -- function Expr_Func ... is (...); -- original
3972 -- [function Expr_Func ...;] -- generated spec
3975 -- pragma SPARK_Mode (Off);
3976 -- [function Expr_Func ... is return ...;] -- generated body
3977 -- end P; -- mode is ON
3979 elsif not Comes_From_Source (N)
3980 and then Present (Spec_Id)
3981 and then Is_Expression_Function (Spec_Id)
3983 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
3984 Set_SPARK_Pragma_Inherited
3985 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
3987 -- Set the SPARK_Mode from the current context (may be overwritten later
3988 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
3989 -- initially on a stand-alone subprogram body, but is then relocated to
3990 -- a generated corresponding spec. In this scenario the mode is shared
3991 -- between the spec and body.
3993 elsif No (SPARK_Pragma (Body_Id)) then
3994 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
3995 Set_SPARK_Pragma_Inherited (Body_Id);
3998 -- A subprogram body may be instantiated or inlined at a later pass.
3999 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4000 -- applied to the initial declaration of the body.
4002 if Present (Spec_Id) then
4003 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4004 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4008 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4009 -- case the body is instantiated or inlined later and out of context.
4010 -- The body uses this attribute to restore the value of the global
4013 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4014 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4016 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4017 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4021 -- Preserve relevant elaboration-related attributes of the context which
4022 -- are no longer available or very expensive to recompute once analysis,
4023 -- resolution, and expansion are over.
4025 if No (Spec_Id) then
4026 Mark_Elaboration_Attributes
4032 -- If this is the proper body of a stub, we must verify that the stub
4033 -- conforms to the body, and to the previous spec if one was present.
4034 -- We know already that the body conforms to that spec. This test is
4035 -- only required for subprograms that come from source.
4037 if Nkind (Parent (N)) = N_Subunit
4038 and then Comes_From_Source (N)
4039 and then not Error_Posted (Body_Id)
4040 and then Nkind (Corresponding_Stub (Parent (N))) =
4041 N_Subprogram_Body_Stub
4044 Old_Id : constant Entity_Id :=
4046 (Specification (Corresponding_Stub (Parent (N))));
4048 Conformant : Boolean := False;
4051 if No (Spec_Id) then
4052 Check_Fully_Conformant (Body_Id, Old_Id);
4056 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4058 if not Conformant then
4060 -- The stub was taken to be a new declaration. Indicate that
4063 Set_Has_Completion (Old_Id, False);
4069 Set_Has_Completion (Body_Id);
4070 Check_Eliminated (Body_Id);
4072 -- Analyze any aspect specifications that appear on the subprogram body
4073 -- stub. Stop the analysis now as the stub does not have a declarative
4074 -- or a statement part, and it cannot be inlined.
4076 if Nkind (N) = N_Subprogram_Body_Stub then
4077 if Has_Aspects (N) then
4078 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4086 -- Note: Normally we don't do any inlining if expansion is off, since
4087 -- we won't generate code in any case. An exception arises in GNATprove
4088 -- mode where we want to expand some calls in place, even with expansion
4089 -- disabled, since the inlining eases formal verification.
4091 if not GNATprove_Mode
4092 and then Expander_Active
4093 and then Serious_Errors_Detected = 0
4094 and then Present (Spec_Id)
4095 and then Has_Pragma_Inline (Spec_Id)
4097 -- Legacy implementation (relying on front-end inlining)
4099 if not Back_End_Inlining then
4100 if (Has_Pragma_Inline_Always (Spec_Id)
4101 and then not Opt.Disable_FE_Inline_Always)
4102 or else (Front_End_Inlining
4103 and then not Opt.Disable_FE_Inline)
4105 Build_Body_To_Inline (N, Spec_Id);
4108 -- New implementation (relying on back-end inlining)
4111 if Has_Pragma_Inline_Always (Spec_Id)
4112 or else Optimization_Level > 0
4114 -- Handle function returning an unconstrained type
4116 if Comes_From_Source (Body_Id)
4117 and then Ekind (Spec_Id) = E_Function
4118 and then Returns_Unconstrained_Type (Spec_Id)
4120 -- If function builds in place, i.e. returns a limited type,
4121 -- inlining cannot be done.
4123 and then not Is_Limited_Type (Etype (Spec_Id))
4125 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4129 Subp_Body : constant Node_Id :=
4130 Unit_Declaration_Node (Body_Id);
4131 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4134 -- Do not pass inlining to the backend if the subprogram
4135 -- has declarations or statements which cannot be inlined
4136 -- by the backend. This check is done here to emit an
4137 -- error instead of the generic warning message reported
4138 -- by the GCC backend (ie. "function might not be
4141 if Present (Subp_Decl)
4142 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4146 elsif Has_Excluded_Statement
4149 (Handled_Statement_Sequence (Subp_Body)))
4153 -- If the backend inlining is available then at this
4154 -- stage we only have to mark the subprogram as inlined.
4155 -- The expander will take care of registering it in the
4156 -- table of subprograms inlined by the backend a part of
4157 -- processing calls to it (cf. Expand_Call)
4160 Set_Is_Inlined (Spec_Id);
4167 -- In GNATprove mode, inline only when there is a separate subprogram
4168 -- declaration for now, as inlining of subprogram bodies acting as
4169 -- declarations, or subprogram stubs, are not supported by front-end
4170 -- inlining. This inlining should occur after analysis of the body, so
4171 -- that it is known whether the value of SPARK_Mode, which can be
4172 -- defined by a pragma inside the body, is applicable to the body.
4173 -- Inlining can be disabled with switch -gnatdm
4175 elsif GNATprove_Mode
4176 and then Full_Analysis
4177 and then not Inside_A_Generic
4178 and then Present (Spec_Id)
4180 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4181 and then Body_Has_SPARK_Mode_On
4182 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4183 and then not Body_Has_Contract
4184 and then not Debug_Flag_M
4186 Build_Body_To_Inline (N, Spec_Id);
4189 -- When generating code, inherited pre/postconditions are handled when
4190 -- expanding the corresponding contract.
4192 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4193 -- of the specification we have to install the private withed units.
4194 -- This holds for child units as well.
4196 if Is_Compilation_Unit (Body_Id)
4197 or else Nkind (Parent (N)) = N_Compilation_Unit
4199 Install_Private_With_Clauses (Body_Id);
4202 Check_Anonymous_Return;
4204 -- Set the Protected_Formal field of each extra formal of the protected
4205 -- subprogram to reference the corresponding extra formal of the
4206 -- subprogram that implements it. For regular formals this occurs when
4207 -- the protected subprogram's declaration is expanded, but the extra
4208 -- formals don't get created until the subprogram is frozen. We need to
4209 -- do this before analyzing the protected subprogram's body so that any
4210 -- references to the original subprogram's extra formals will be changed
4211 -- refer to the implementing subprogram's formals (see Expand_Formal).
4213 if Present (Spec_Id)
4214 and then Is_Protected_Type (Scope (Spec_Id))
4215 and then Present (Protected_Body_Subprogram (Spec_Id))
4218 Impl_Subp : constant Entity_Id :=
4219 Protected_Body_Subprogram (Spec_Id);
4220 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4221 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4224 while Present (Prot_Ext_Formal) loop
4225 pragma Assert (Present (Impl_Ext_Formal));
4226 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4227 Next_Formal_With_Extras (Prot_Ext_Formal);
4228 Next_Formal_With_Extras (Impl_Ext_Formal);
4233 -- Now we can go on to analyze the body
4235 HSS := Handled_Statement_Sequence (N);
4236 Set_Actual_Subtypes (N, Current_Scope);
4238 -- Add a declaration for the Protection object, renaming declarations
4239 -- for discriminals and privals and finally a declaration for the entry
4240 -- family index (if applicable). This form of early expansion is done
4241 -- when the Expander is active because Install_Private_Data_Declarations
4242 -- references entities which were created during regular expansion. The
4243 -- subprogram entity must come from source, and not be an internally
4244 -- generated subprogram.
4247 and then Present (Prot_Typ)
4248 and then Present (Spec_Id)
4249 and then Comes_From_Source (Spec_Id)
4250 and then not Is_Eliminated (Spec_Id)
4252 Install_Private_Data_Declarations
4253 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4256 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4257 -- may now appear in parameter and result profiles. Since the analysis
4258 -- of a subprogram body may use the parameter and result profile of the
4259 -- spec, swap any limited views with their non-limited counterpart.
4261 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4262 Exch_Views := Exchange_Limited_Views (Spec_Id);
4265 -- If the return type is an anonymous access type whose designated type
4266 -- is the limited view of a class-wide type and the non-limited view is
4267 -- available, update the return type accordingly.
4269 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4275 Rtyp := Etype (Spec_Id);
4277 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4278 Etyp := Directly_Designated_Type (Rtyp);
4280 if Is_Class_Wide_Type (Etyp)
4281 and then From_Limited_With (Etyp)
4284 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4290 -- Analyze any aspect specifications that appear on the subprogram body
4292 if Has_Aspects (N) then
4293 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4296 Analyze_Declarations (Declarations (N));
4298 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4300 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4301 if Present (SPARK_Pragma (Spec_Id)) then
4302 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4304 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4306 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4307 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4308 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4310 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4313 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4317 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4318 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4319 Error_Msg_Sloc := Sloc (Spec_Id);
4321 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4325 -- A subprogram body freezes its own contract. Analyze the contract
4326 -- after the declarations of the body have been processed as pragmas
4327 -- are now chained on the contract of the subprogram body.
4329 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4331 -- Check completion, and analyze the statements
4334 Inspect_Deferred_Constant_Completion (Declarations (N));
4337 -- Deal with end of scope processing for the body
4339 Process_End_Label (HSS, 't', Current_Scope);
4340 Update_Use_Clause_Chain;
4343 -- If we are compiling an entry wrapper, remove the enclosing
4344 -- synchronized object from the stack.
4346 if Is_Entry_Wrapper (Body_Id) then
4350 Check_Subprogram_Order (N);
4351 Set_Analyzed (Body_Id);
4353 -- If we have a separate spec, then the analysis of the declarations
4354 -- caused the entities in the body to be chained to the spec id, but
4355 -- we want them chained to the body id. Only the formal parameters
4356 -- end up chained to the spec id in this case.
4358 if Present (Spec_Id) then
4360 -- We must conform to the categorization of our spec
4362 Validate_Categorization_Dependency (N, Spec_Id);
4364 -- And if this is a child unit, the parent units must conform
4366 if Is_Child_Unit (Spec_Id) then
4367 Validate_Categorization_Dependency
4368 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4371 -- Here is where we move entities from the spec to the body
4373 -- Case where there are entities that stay with the spec
4375 if Present (Last_Real_Spec_Entity) then
4377 -- No body entities (happens when the only real spec entities come
4378 -- from precondition and postcondition pragmas).
4380 if No (Last_Entity (Body_Id)) then
4381 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4383 -- Body entities present (formals), so chain stuff past them
4387 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4390 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4391 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4392 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4394 -- Case where there are no spec entities, in this case there can be
4395 -- no body entities either, so just move everything.
4397 -- If the body is generated for an expression function, it may have
4398 -- been preanalyzed already, if 'access was applied to it.
4401 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4402 N_Expression_Function
4404 pragma Assert (No (Last_Entity (Body_Id)));
4408 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4409 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4410 Set_First_Entity (Spec_Id, Empty);
4411 Set_Last_Entity (Spec_Id, Empty);
4414 -- Otherwise the body does not complete a previous declaration. Check
4415 -- the categorization of the body against the units it withs.
4418 Validate_Categorization_Dependency (N, Body_Id);
4421 Check_Missing_Return;
4423 -- Now we are going to check for variables that are never modified in
4424 -- the body of the procedure. But first we deal with a special case
4425 -- where we want to modify this check. If the body of the subprogram
4426 -- starts with a raise statement or its equivalent, or if the body
4427 -- consists entirely of a null statement, then it is pretty obvious that
4428 -- it is OK to not reference the parameters. For example, this might be
4429 -- the following common idiom for a stubbed function: statement of the
4430 -- procedure raises an exception. In particular this deals with the
4431 -- common idiom of a stubbed function, which appears something like:
4433 -- function F (A : Integer) return Some_Type;
4436 -- raise Program_Error;
4440 -- Here the purpose of X is simply to satisfy the annoying requirement
4441 -- in Ada that there be at least one return, and we certainly do not
4442 -- want to go posting warnings on X that it is not initialized. On
4443 -- the other hand, if X is entirely unreferenced that should still
4446 -- What we do is to detect these cases, and if we find them, flag the
4447 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4448 -- suppress unwanted warnings. For the case of the function stub above
4449 -- we have a special test to set X as apparently assigned to suppress
4456 -- Skip call markers installed by the ABE mechanism, labels, and
4457 -- Push_xxx_Error_Label to find the first real statement.
4459 Stm := First (Statements (HSS));
4460 while Nkind_In (Stm, N_Call_Marker, N_Label)
4461 or else Nkind (Stm) in N_Push_xxx_Label
4466 -- Do the test on the original statement before expansion
4469 Ostm : constant Node_Id := Original_Node (Stm);
4472 -- If explicit raise statement, turn on flag
4474 if Nkind (Ostm) = N_Raise_Statement then
4475 Set_Trivial_Subprogram (Stm);
4477 -- If null statement, and no following statements, turn on flag
4479 elsif Nkind (Stm) = N_Null_Statement
4480 and then Comes_From_Source (Stm)
4481 and then No (Next (Stm))
4483 Set_Trivial_Subprogram (Stm);
4485 -- Check for explicit call cases which likely raise an exception
4487 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4488 if Is_Entity_Name (Name (Ostm)) then
4490 Ent : constant Entity_Id := Entity (Name (Ostm));
4493 -- If the procedure is marked No_Return, then likely it
4494 -- raises an exception, but in any case it is not coming
4495 -- back here, so turn on the flag.
4498 and then Ekind (Ent) = E_Procedure
4499 and then No_Return (Ent)
4501 Set_Trivial_Subprogram (Stm);
4509 -- Check for variables that are never modified
4516 -- If there is a separate spec, then transfer Never_Set_In_Source
4517 -- flags from out parameters to the corresponding entities in the
4518 -- body. The reason we do that is we want to post error flags on
4519 -- the body entities, not the spec entities.
4521 if Present (Spec_Id) then
4522 E1 := First_Entity (Spec_Id);
4523 while Present (E1) loop
4524 if Ekind (E1) = E_Out_Parameter then
4525 E2 := First_Entity (Body_Id);
4526 while Present (E2) loop
4527 exit when Chars (E1) = Chars (E2);
4531 if Present (E2) then
4532 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4540 -- Check references of the subprogram spec when we are dealing with
4541 -- an expression function due to it having a generated body.
4542 -- Otherwise, we simply check the formals of the subprogram body.
4544 if Present (Spec_Id)
4545 and then Is_Expression_Function (Spec_Id)
4547 Check_References (Spec_Id);
4549 Check_References (Body_Id);
4553 -- Check for nested subprogram, and mark outer level subprogram if so
4559 if Present (Spec_Id) then
4566 Ent := Enclosing_Subprogram (Ent);
4567 exit when No (Ent) or else Is_Subprogram (Ent);
4570 if Present (Ent) then
4571 Set_Has_Nested_Subprogram (Ent);
4575 -- Restore the limited views in the spec, if any, to let the back end
4576 -- process it without running into circularities.
4578 if Exch_Views /= No_Elist then
4579 Restore_Limited_Views (Exch_Views);
4582 if Mask_Types /= No_Elist then
4583 Unmask_Unfrozen_Types (Mask_Types);
4586 if Present (Desig_View) then
4587 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4591 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4592 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4593 end Analyze_Subprogram_Body_Helper;
4595 ------------------------------------
4596 -- Analyze_Subprogram_Declaration --
4597 ------------------------------------
4599 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4600 Scop : constant Entity_Id := Current_Scope;
4601 Designator : Entity_Id;
4603 Is_Completion : Boolean;
4604 -- Indicates whether a null procedure declaration is a completion
4607 -- Null procedures are not allowed in SPARK
4609 if Nkind (Specification (N)) = N_Procedure_Specification
4610 and then Null_Present (Specification (N))
4612 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4614 -- Null procedures are allowed in protected types, following the
4615 -- recent AI12-0147.
4617 if Is_Protected_Type (Current_Scope)
4618 and then Ada_Version < Ada_2012
4620 Error_Msg_N ("protected operation cannot be a null procedure", N);
4623 Analyze_Null_Procedure (N, Is_Completion);
4625 -- The null procedure acts as a body, nothing further is needed
4627 if Is_Completion then
4632 Designator := Analyze_Subprogram_Specification (Specification (N));
4634 -- A reference may already have been generated for the unit name, in
4635 -- which case the following call is redundant. However it is needed for
4636 -- declarations that are the rewriting of an expression function.
4638 Generate_Definition (Designator);
4640 -- Set the SPARK mode from the current context (may be overwritten later
4641 -- with explicit pragma). This is not done for entry barrier functions
4642 -- because they are generated outside the protected type and should not
4643 -- carry the mode of the enclosing context.
4645 if Nkind (N) = N_Subprogram_Declaration
4646 and then Is_Entry_Barrier_Function (N)
4651 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4652 Set_SPARK_Pragma_Inherited (Designator);
4655 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4656 -- the body of this subprogram is instantiated or inlined later and out
4657 -- of context. The body uses this attribute to restore the value of the
4660 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4661 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4664 -- Preserve relevant elaboration-related attributes of the context which
4665 -- are no longer available or very expensive to recompute once analysis,
4666 -- resolution, and expansion are over.
4668 Mark_Elaboration_Attributes
4669 (N_Id => Designator,
4673 if Debug_Flag_C then
4674 Write_Str ("==> subprogram spec ");
4675 Write_Name (Chars (Designator));
4676 Write_Str (" from ");
4677 Write_Location (Sloc (N));
4682 Validate_RCI_Subprogram_Declaration (N);
4683 New_Overloaded_Entity (Designator);
4684 Check_Delayed_Subprogram (Designator);
4686 -- If the type of the first formal of the current subprogram is a non-
4687 -- generic tagged private type, mark the subprogram as being a private
4688 -- primitive. Ditto if this is a function with controlling result, and
4689 -- the return type is currently private. In both cases, the type of the
4690 -- controlling argument or result must be in the current scope for the
4691 -- operation to be primitive.
4693 if Has_Controlling_Result (Designator)
4694 and then Is_Private_Type (Etype (Designator))
4695 and then Scope (Etype (Designator)) = Current_Scope
4696 and then not Is_Generic_Actual_Type (Etype (Designator))
4698 Set_Is_Private_Primitive (Designator);
4700 elsif Present (First_Formal (Designator)) then
4702 Formal_Typ : constant Entity_Id :=
4703 Etype (First_Formal (Designator));
4705 Set_Is_Private_Primitive (Designator,
4706 Is_Tagged_Type (Formal_Typ)
4707 and then Scope (Formal_Typ) = Current_Scope
4708 and then Is_Private_Type (Formal_Typ)
4709 and then not Is_Generic_Actual_Type (Formal_Typ));
4713 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4716 if Ada_Version >= Ada_2005
4717 and then Comes_From_Source (N)
4718 and then Is_Dispatching_Operation (Designator)
4725 if Has_Controlling_Result (Designator) then
4726 Etyp := Etype (Designator);
4729 E := First_Entity (Designator);
4731 and then Is_Formal (E)
4732 and then not Is_Controlling_Formal (E)
4740 if Is_Access_Type (Etyp) then
4741 Etyp := Directly_Designated_Type (Etyp);
4744 if Is_Interface (Etyp)
4745 and then not Is_Abstract_Subprogram (Designator)
4746 and then not (Ekind (Designator) = E_Procedure
4747 and then Null_Present (Specification (N)))
4749 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4751 -- Specialize error message based on procedures vs. functions,
4752 -- since functions can't be null subprograms.
4754 if Ekind (Designator) = E_Procedure then
4756 ("interface procedure % must be abstract or null", N);
4759 ("interface function % must be abstract", N);
4765 -- What is the following code for, it used to be
4767 -- ??? Set_Suppress_Elaboration_Checks
4768 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4770 -- The following seems equivalent, but a bit dubious
4772 if Elaboration_Checks_Suppressed (Designator) then
4773 Set_Kill_Elaboration_Checks (Designator);
4776 -- For a compilation unit, set body required. This flag will only be
4777 -- reset if a valid Import or Interface pragma is processed later on.
4779 if Nkind (Parent (N)) = N_Compilation_Unit then
4780 Set_Body_Required (Parent (N), True);
4782 if Ada_Version >= Ada_2005
4783 and then Nkind (Specification (N)) = N_Procedure_Specification
4784 and then Null_Present (Specification (N))
4787 ("null procedure cannot be declared at library level", N);
4791 Generate_Reference_To_Formals (Designator);
4792 Check_Eliminated (Designator);
4794 if Debug_Flag_C then
4796 Write_Str ("<== subprogram spec ");
4797 Write_Name (Chars (Designator));
4798 Write_Str (" from ");
4799 Write_Location (Sloc (N));
4803 -- Indicate that this is a protected operation, because it may be used
4804 -- in subsequent declarations within the protected type.
4806 if Is_Protected_Type (Current_Scope) then
4807 Set_Convention (Designator, Convention_Protected);
4810 List_Inherited_Pre_Post_Aspects (Designator);
4812 -- Process the aspects before establishing the proper categorization in
4813 -- case the subprogram is a compilation unit and one of its aspects is
4814 -- converted into a categorization pragma.
4816 if Has_Aspects (N) then
4817 Analyze_Aspect_Specifications (N, Designator);
4820 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4821 Set_Categorization_From_Scope (Designator, Scop);
4823 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4824 -- proper categorization of the unit based on its pragmas.
4827 Push_Scope (Designator);
4828 Set_Categorization_From_Pragmas (N);
4829 Validate_Categorization_Dependency (N, Designator);
4832 end Analyze_Subprogram_Declaration;
4834 --------------------------------------
4835 -- Analyze_Subprogram_Specification --
4836 --------------------------------------
4838 -- Reminder: N here really is a subprogram specification (not a subprogram
4839 -- declaration). This procedure is called to analyze the specification in
4840 -- both subprogram bodies and subprogram declarations (specs).
4842 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4843 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4844 -- Determine whether entity E denotes the spec or body of an invariant
4847 ------------------------------------
4848 -- Is_Invariant_Procedure_Or_Body --
4849 ------------------------------------
4851 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4852 Decl : constant Node_Id := Unit_Declaration_Node (E);
4856 if Nkind (Decl) = N_Subprogram_Body then
4857 Spec := Corresponding_Spec (Decl);
4864 and then Ekind (Spec) = E_Procedure
4865 and then (Is_Partial_Invariant_Procedure (Spec)
4866 or else Is_Invariant_Procedure (Spec));
4867 end Is_Invariant_Procedure_Or_Body;
4871 Designator : constant Entity_Id := Defining_Entity (N);
4872 Formals : constant List_Id := Parameter_Specifications (N);
4874 -- Start of processing for Analyze_Subprogram_Specification
4877 -- User-defined operator is not allowed in SPARK, except as a renaming
4879 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4880 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4882 Check_SPARK_05_Restriction
4883 ("user-defined operator is not allowed", N);
4886 -- Proceed with analysis. Do not emit a cross-reference entry if the
4887 -- specification comes from an expression function, because it may be
4888 -- the completion of a previous declaration. If it is not, the cross-
4889 -- reference entry will be emitted for the new subprogram declaration.
4891 if Nkind (Parent (N)) /= N_Expression_Function then
4892 Generate_Definition (Designator);
4895 if Nkind (N) = N_Function_Specification then
4896 Set_Ekind (Designator, E_Function);
4897 Set_Mechanism (Designator, Default_Mechanism);
4899 Set_Ekind (Designator, E_Procedure);
4900 Set_Etype (Designator, Standard_Void_Type);
4903 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4904 -- those subprograms which could be inlined in GNATprove mode (because
4905 -- Body_To_Inline is non-Empty) but should not be inlined.
4907 if GNATprove_Mode then
4908 Set_Is_Inlined_Always (Designator);
4911 -- Introduce new scope for analysis of the formals and the return type
4913 Set_Scope (Designator, Current_Scope);
4915 if Present (Formals) then
4916 Push_Scope (Designator);
4917 Process_Formals (Formals, N);
4919 -- Check dimensions in N for formals with default expression
4921 Analyze_Dimension_Formals (N, Formals);
4923 -- Ada 2005 (AI-345): If this is an overriding operation of an
4924 -- inherited interface operation, and the controlling type is
4925 -- a synchronized type, replace the type with its corresponding
4926 -- record, to match the proper signature of an overriding operation.
4927 -- Same processing for an access parameter whose designated type is
4928 -- derived from a synchronized interface.
4930 -- This modification is not done for invariant procedures because
4931 -- the corresponding record may not necessarely be visible when the
4932 -- concurrent type acts as the full view of a private type.
4935 -- type Prot is private with Type_Invariant => ...;
4936 -- procedure ConcInvariant (Obj : Prot);
4938 -- protected type Prot is ...;
4939 -- type Concurrent_Record_Prot is record ...;
4940 -- procedure ConcInvariant (Obj : Prot) is
4942 -- end ConcInvariant;
4945 -- In the example above, both the spec and body of the invariant
4946 -- procedure must utilize the private type as the controlling type.
4948 if Ada_Version >= Ada_2005
4949 and then not Is_Invariant_Procedure_Or_Body (Designator)
4953 Formal_Typ : Entity_Id;
4954 Rec_Typ : Entity_Id;
4955 Desig_Typ : Entity_Id;
4958 Formal := First_Formal (Designator);
4959 while Present (Formal) loop
4960 Formal_Typ := Etype (Formal);
4962 if Is_Concurrent_Type (Formal_Typ)
4963 and then Present (Corresponding_Record_Type (Formal_Typ))
4965 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4967 if Present (Interfaces (Rec_Typ)) then
4968 Set_Etype (Formal, Rec_Typ);
4971 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4972 Desig_Typ := Designated_Type (Formal_Typ);
4974 if Is_Concurrent_Type (Desig_Typ)
4975 and then Present (Corresponding_Record_Type (Desig_Typ))
4977 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4979 if Present (Interfaces (Rec_Typ)) then
4980 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
4985 Next_Formal (Formal);
4992 -- The subprogram scope is pushed and popped around the processing of
4993 -- the return type for consistency with call above to Process_Formals
4994 -- (which itself can call Analyze_Return_Type), and to ensure that any
4995 -- itype created for the return type will be associated with the proper
4998 elsif Nkind (N) = N_Function_Specification then
4999 Push_Scope (Designator);
5000 Analyze_Return_Type (N);
5006 if Nkind (N) = N_Function_Specification then
5008 -- Deal with operator symbol case
5010 if Nkind (Designator) = N_Defining_Operator_Symbol then
5011 Valid_Operator_Definition (Designator);
5014 May_Need_Actuals (Designator);
5016 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5017 -- the subprogram is abstract also. This does not apply to renaming
5018 -- declarations, where abstractness is inherited, and to subprogram
5019 -- bodies generated for stream operations, which become renamings as
5022 -- In case of primitives associated with abstract interface types
5023 -- the check is applied later (see Analyze_Subprogram_Declaration).
5025 if not Nkind_In (Original_Node (Parent (N)),
5026 N_Abstract_Subprogram_Declaration,
5027 N_Formal_Abstract_Subprogram_Declaration,
5028 N_Subprogram_Renaming_Declaration)
5030 if Is_Abstract_Type (Etype (Designator))
5031 and then not Is_Interface (Etype (Designator))
5034 ("function that returns abstract type must be abstract", N);
5036 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5037 -- access result whose designated type is abstract.
5039 elsif Ada_Version >= Ada_2012
5040 and then Nkind (Result_Definition (N)) = N_Access_Definition
5042 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5043 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5046 ("function whose access result designates abstract type "
5047 & "must be abstract", N);
5053 end Analyze_Subprogram_Specification;
5055 -----------------------
5056 -- Check_Conformance --
5057 -----------------------
5059 procedure Check_Conformance
5060 (New_Id : Entity_Id;
5062 Ctype : Conformance_Type;
5064 Conforms : out Boolean;
5065 Err_Loc : Node_Id := Empty;
5066 Get_Inst : Boolean := False;
5067 Skip_Controlling_Formals : Boolean := False)
5069 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5070 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5071 -- If Errmsg is True, then processing continues to post an error message
5072 -- for conformance error on given node. Two messages are output. The
5073 -- first message points to the previous declaration with a general "no
5074 -- conformance" message. The second is the detailed reason, supplied as
5075 -- Msg. The parameter N provide information for a possible & insertion
5076 -- in the message, and also provides the location for posting the
5077 -- message in the absence of a specified Err_Loc location.
5079 function Conventions_Match
5081 Id2 : Entity_Id) return Boolean;
5082 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5085 -----------------------
5086 -- Conformance_Error --
5087 -----------------------
5089 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5096 if No (Err_Loc) then
5102 Error_Msg_Sloc := Sloc (Old_Id);
5105 when Type_Conformant =>
5106 Error_Msg_N -- CODEFIX
5107 ("not type conformant with declaration#!", Enode);
5109 when Mode_Conformant =>
5110 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5112 ("not mode conformant with operation inherited#!",
5116 ("not mode conformant with declaration#!", Enode);
5119 when Subtype_Conformant =>
5120 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5122 ("not subtype conformant with operation inherited#!",
5126 ("not subtype conformant with declaration#!", Enode);
5129 when Fully_Conformant =>
5130 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5131 Error_Msg_N -- CODEFIX
5132 ("not fully conformant with operation inherited#!",
5135 Error_Msg_N -- CODEFIX
5136 ("not fully conformant with declaration#!", Enode);
5140 Error_Msg_NE (Msg, Enode, N);
5142 end Conformance_Error;
5144 -----------------------
5145 -- Conventions_Match --
5146 -----------------------
5148 function Conventions_Match
5150 Id2 : Entity_Id) return Boolean
5153 -- Ignore the conventions of anonymous access-to-subprogram types
5154 -- and subprogram types because these are internally generated and
5155 -- the only way these may receive a convention is if they inherit
5156 -- the convention of a related subprogram.
5158 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5161 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5166 -- Otherwise compare the conventions directly
5169 return Convention (Id1) = Convention (Id2);
5171 end Conventions_Match;
5175 Old_Type : constant Entity_Id := Etype (Old_Id);
5176 New_Type : constant Entity_Id := Etype (New_Id);
5177 Old_Formal : Entity_Id;
5178 New_Formal : Entity_Id;
5179 Access_Types_Match : Boolean;
5180 Old_Formal_Base : Entity_Id;
5181 New_Formal_Base : Entity_Id;
5183 -- Start of processing for Check_Conformance
5188 -- We need a special case for operators, since they don't appear
5191 if Ctype = Type_Conformant then
5192 if Ekind (New_Id) = E_Operator
5193 and then Operator_Matches_Spec (New_Id, Old_Id)
5199 -- If both are functions/operators, check return types conform
5201 if Old_Type /= Standard_Void_Type
5203 New_Type /= Standard_Void_Type
5205 -- If we are checking interface conformance we omit controlling
5206 -- arguments and result, because we are only checking the conformance
5207 -- of the remaining parameters.
5209 if Has_Controlling_Result (Old_Id)
5210 and then Has_Controlling_Result (New_Id)
5211 and then Skip_Controlling_Formals
5215 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5216 if Ctype >= Subtype_Conformant
5217 and then not Predicates_Match (Old_Type, New_Type)
5220 ("\predicate of return type does not match!", New_Id);
5223 ("\return type does not match!", New_Id);
5229 -- Ada 2005 (AI-231): In case of anonymous access types check the
5230 -- null-exclusion and access-to-constant attributes match.
5232 if Ada_Version >= Ada_2005
5233 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5235 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5236 or else Is_Access_Constant (Etype (Old_Type)) /=
5237 Is_Access_Constant (Etype (New_Type)))
5239 Conformance_Error ("\return type does not match!", New_Id);
5243 -- If either is a function/operator and the other isn't, error
5245 elsif Old_Type /= Standard_Void_Type
5246 or else New_Type /= Standard_Void_Type
5248 Conformance_Error ("\functions can only match functions!", New_Id);
5252 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5253 -- If this is a renaming as body, refine error message to indicate that
5254 -- the conflict is with the original declaration. If the entity is not
5255 -- frozen, the conventions don't have to match, the one of the renamed
5256 -- entity is inherited.
5258 if Ctype >= Subtype_Conformant then
5259 if not Conventions_Match (Old_Id, New_Id) then
5260 if not Is_Frozen (New_Id) then
5263 elsif Present (Err_Loc)
5264 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5265 and then Present (Corresponding_Spec (Err_Loc))
5267 Error_Msg_Name_1 := Chars (New_Id);
5269 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5270 Conformance_Error ("\prior declaration for% has convention %!");
5273 Conformance_Error ("\calling conventions do not match!");
5278 elsif Is_Formal_Subprogram (Old_Id)
5279 or else Is_Formal_Subprogram (New_Id)
5280 or else (Is_Subprogram (New_Id)
5281 and then Present (Alias (New_Id))
5282 and then Is_Formal_Subprogram (Alias (New_Id)))
5285 ("\formal subprograms are not subtype conformant "
5286 & "(RM 6.3.1 (17/3))");
5290 -- Deal with parameters
5292 -- Note: we use the entity information, rather than going directly
5293 -- to the specification in the tree. This is not only simpler, but
5294 -- absolutely necessary for some cases of conformance tests between
5295 -- operators, where the declaration tree simply does not exist.
5297 Old_Formal := First_Formal (Old_Id);
5298 New_Formal := First_Formal (New_Id);
5299 while Present (Old_Formal) and then Present (New_Formal) loop
5300 if Is_Controlling_Formal (Old_Formal)
5301 and then Is_Controlling_Formal (New_Formal)
5302 and then Skip_Controlling_Formals
5304 -- The controlling formals will have different types when
5305 -- comparing an interface operation with its match, but both
5306 -- or neither must be access parameters.
5308 if Is_Access_Type (Etype (Old_Formal))
5310 Is_Access_Type (Etype (New_Formal))
5312 goto Skip_Controlling_Formal;
5315 ("\access parameter does not match!", New_Formal);
5319 -- Ada 2012: Mode conformance also requires that formal parameters
5320 -- be both aliased, or neither.
5322 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5323 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5325 ("\aliased parameter mismatch!", New_Formal);
5329 if Ctype = Fully_Conformant then
5331 -- Names must match. Error message is more accurate if we do
5332 -- this before checking that the types of the formals match.
5334 if Chars (Old_Formal) /= Chars (New_Formal) then
5335 Conformance_Error ("\name& does not match!", New_Formal);
5337 -- Set error posted flag on new formal as well to stop
5338 -- junk cascaded messages in some cases.
5340 Set_Error_Posted (New_Formal);
5344 -- Null exclusion must match
5346 if Null_Exclusion_Present (Parent (Old_Formal))
5348 Null_Exclusion_Present (Parent (New_Formal))
5350 -- Only give error if both come from source. This should be
5351 -- investigated some time, since it should not be needed ???
5353 if Comes_From_Source (Old_Formal)
5355 Comes_From_Source (New_Formal)
5358 ("\null exclusion for& does not match", New_Formal);
5360 -- Mark error posted on the new formal to avoid duplicated
5361 -- complaint about types not matching.
5363 Set_Error_Posted (New_Formal);
5368 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5369 -- case occurs whenever a subprogram is being renamed and one of its
5370 -- parameters imposes a null exclusion. For example:
5372 -- type T is null record;
5373 -- type Acc_T is access T;
5374 -- subtype Acc_T_Sub is Acc_T;
5376 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5377 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5380 Old_Formal_Base := Etype (Old_Formal);
5381 New_Formal_Base := Etype (New_Formal);
5384 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5385 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5388 Access_Types_Match := Ada_Version >= Ada_2005
5390 -- Ensure that this rule is only applied when New_Id is a
5391 -- renaming of Old_Id.
5393 and then Nkind (Parent (Parent (New_Id))) =
5394 N_Subprogram_Renaming_Declaration
5395 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5396 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5397 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5399 -- Now handle the allowed access-type case
5401 and then Is_Access_Type (Old_Formal_Base)
5402 and then Is_Access_Type (New_Formal_Base)
5404 -- The type kinds must match. The only exception occurs with
5405 -- multiple generics of the form:
5408 -- type F is private; type A is private;
5409 -- type F_Ptr is access F; type A_Ptr is access A;
5410 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5411 -- package F_Pack is ... package A_Pack is
5412 -- package F_Inst is
5413 -- new F_Pack (A, A_Ptr, A_P);
5415 -- When checking for conformance between the parameters of A_P
5416 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5417 -- because the compiler has transformed A_Ptr into a subtype of
5418 -- F_Ptr. We catch this case in the code below.
5420 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5422 (Is_Generic_Type (Old_Formal_Base)
5423 and then Is_Generic_Type (New_Formal_Base)
5424 and then Is_Internal (New_Formal_Base)
5425 and then Etype (Etype (New_Formal_Base)) =
5427 and then Directly_Designated_Type (Old_Formal_Base) =
5428 Directly_Designated_Type (New_Formal_Base)
5429 and then ((Is_Itype (Old_Formal_Base)
5430 and then Can_Never_Be_Null (Old_Formal_Base))
5432 (Is_Itype (New_Formal_Base)
5433 and then Can_Never_Be_Null (New_Formal_Base)));
5435 -- Types must always match. In the visible part of an instance,
5436 -- usual overloading rules for dispatching operations apply, and
5437 -- we check base types (not the actual subtypes).
5439 if In_Instance_Visible_Part
5440 and then Is_Dispatching_Operation (New_Id)
5442 if not Conforming_Types
5443 (T1 => Base_Type (Etype (Old_Formal)),
5444 T2 => Base_Type (Etype (New_Formal)),
5446 Get_Inst => Get_Inst)
5447 and then not Access_Types_Match
5449 Conformance_Error ("\type of & does not match!", New_Formal);
5453 elsif not Conforming_Types
5454 (T1 => Old_Formal_Base,
5455 T2 => New_Formal_Base,
5457 Get_Inst => Get_Inst)
5458 and then not Access_Types_Match
5460 -- Don't give error message if old type is Any_Type. This test
5461 -- avoids some cascaded errors, e.g. in case of a bad spec.
5463 if Errmsg and then Old_Formal_Base = Any_Type then
5466 if Ctype >= Subtype_Conformant
5468 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5471 ("\predicate of & does not match!", New_Formal);
5474 ("\type of & does not match!", New_Formal);
5476 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5478 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5486 -- For mode conformance, mode must match
5488 if Ctype >= Mode_Conformant then
5489 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5490 if not Ekind_In (New_Id, E_Function, E_Procedure)
5491 or else not Is_Primitive_Wrapper (New_Id)
5493 Conformance_Error ("\mode of & does not match!", New_Formal);
5497 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5499 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5501 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5504 ("\mode of & does not match!", New_Formal);
5511 -- Part of mode conformance for access types is having the same
5512 -- constant modifier.
5514 elsif Access_Types_Match
5515 and then Is_Access_Constant (Old_Formal_Base) /=
5516 Is_Access_Constant (New_Formal_Base)
5519 ("\constant modifier does not match!", New_Formal);
5524 if Ctype >= Subtype_Conformant then
5526 -- Ada 2005 (AI-231): In case of anonymous access types check
5527 -- the null-exclusion and access-to-constant attributes must
5528 -- match. For null exclusion, we test the types rather than the
5529 -- formals themselves, since the attribute is only set reliably
5530 -- on the formals in the Ada 95 case, and we exclude the case
5531 -- where Old_Formal is marked as controlling, to avoid errors
5532 -- when matching completing bodies with dispatching declarations
5533 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5535 if Ada_Version >= Ada_2005
5536 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5537 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5539 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5540 Can_Never_Be_Null (Etype (New_Formal))
5542 not Is_Controlling_Formal (Old_Formal))
5544 Is_Access_Constant (Etype (Old_Formal)) /=
5545 Is_Access_Constant (Etype (New_Formal)))
5547 -- Do not complain if error already posted on New_Formal. This
5548 -- avoids some redundant error messages.
5550 and then not Error_Posted (New_Formal)
5552 -- It is allowed to omit the null-exclusion in case of stream
5553 -- attribute subprograms. We recognize stream subprograms
5554 -- through their TSS-generated suffix.
5557 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5560 if TSS_Name /= TSS_Stream_Read
5561 and then TSS_Name /= TSS_Stream_Write
5562 and then TSS_Name /= TSS_Stream_Input
5563 and then TSS_Name /= TSS_Stream_Output
5565 -- Here we have a definite conformance error. It is worth
5566 -- special casing the error message for the case of a
5567 -- controlling formal (which excludes null).
5569 if Is_Controlling_Formal (New_Formal) then
5570 Error_Msg_Node_2 := Scope (New_Formal);
5572 ("\controlling formal & of & excludes null, "
5573 & "declaration must exclude null as well",
5576 -- Normal case (couldn't we give more detail here???)
5580 ("\type of & does not match!", New_Formal);
5589 -- Full conformance checks
5591 if Ctype = Fully_Conformant then
5593 -- We have checked already that names match
5595 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5597 -- Check default expressions for in parameters
5600 NewD : constant Boolean :=
5601 Present (Default_Value (New_Formal));
5602 OldD : constant Boolean :=
5603 Present (Default_Value (Old_Formal));
5605 if NewD or OldD then
5607 -- The old default value has been analyzed because the
5608 -- current full declaration will have frozen everything
5609 -- before. The new default value has not been analyzed,
5610 -- so analyze it now before we check for conformance.
5613 Push_Scope (New_Id);
5614 Preanalyze_Spec_Expression
5615 (Default_Value (New_Formal), Etype (New_Formal));
5619 if not (NewD and OldD)
5620 or else not Fully_Conformant_Expressions
5621 (Default_Value (Old_Formal),
5622 Default_Value (New_Formal))
5625 ("\default expression for & does not match!",
5634 -- A couple of special checks for Ada 83 mode. These checks are
5635 -- skipped if either entity is an operator in package Standard,
5636 -- or if either old or new instance is not from the source program.
5638 if Ada_Version = Ada_83
5639 and then Sloc (Old_Id) > Standard_Location
5640 and then Sloc (New_Id) > Standard_Location
5641 and then Comes_From_Source (Old_Id)
5642 and then Comes_From_Source (New_Id)
5645 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5646 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5649 -- Explicit IN must be present or absent in both cases. This
5650 -- test is required only in the full conformance case.
5652 if In_Present (Old_Param) /= In_Present (New_Param)
5653 and then Ctype = Fully_Conformant
5656 ("\(Ada 83) IN must appear in both declarations",
5661 -- Grouping (use of comma in param lists) must be the same
5662 -- This is where we catch a misconformance like:
5665 -- A : Integer; B : Integer
5667 -- which are represented identically in the tree except
5668 -- for the setting of the flags More_Ids and Prev_Ids.
5670 if More_Ids (Old_Param) /= More_Ids (New_Param)
5671 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5674 ("\grouping of & does not match!", New_Formal);
5680 -- This label is required when skipping controlling formals
5682 <<Skip_Controlling_Formal>>
5684 Next_Formal (Old_Formal);
5685 Next_Formal (New_Formal);
5688 if Present (Old_Formal) then
5689 Conformance_Error ("\too few parameters!");
5692 elsif Present (New_Formal) then
5693 Conformance_Error ("\too many parameters!", New_Formal);
5696 end Check_Conformance;
5698 -----------------------
5699 -- Check_Conventions --
5700 -----------------------
5702 procedure Check_Conventions (Typ : Entity_Id) is
5703 Ifaces_List : Elist_Id;
5705 procedure Check_Convention (Op : Entity_Id);
5706 -- Verify that the convention of inherited dispatching operation Op is
5707 -- consistent among all subprograms it overrides. In order to minimize
5708 -- the search, Search_From is utilized to designate a specific point in
5709 -- the list rather than iterating over the whole list once more.
5711 ----------------------
5712 -- Check_Convention --
5713 ----------------------
5715 procedure Check_Convention (Op : Entity_Id) is
5716 Op_Conv : constant Convention_Id := Convention (Op);
5717 Iface_Conv : Convention_Id;
5718 Iface_Elmt : Elmt_Id;
5719 Iface_Prim_Elmt : Elmt_Id;
5720 Iface_Prim : Entity_Id;
5723 Iface_Elmt := First_Elmt (Ifaces_List);
5724 while Present (Iface_Elmt) loop
5726 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5727 while Present (Iface_Prim_Elmt) loop
5728 Iface_Prim := Node (Iface_Prim_Elmt);
5729 Iface_Conv := Convention (Iface_Prim);
5731 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5732 and then Iface_Conv /= Op_Conv
5735 ("inconsistent conventions in primitive operations", Typ);
5737 Error_Msg_Name_1 := Chars (Op);
5738 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5739 Error_Msg_Sloc := Sloc (Op);
5741 if Comes_From_Source (Op) or else No (Alias (Op)) then
5742 if not Present (Overridden_Operation (Op)) then
5743 Error_Msg_N ("\\primitive % defined #", Typ);
5746 ("\\overriding operation % with "
5747 & "convention % defined #", Typ);
5750 else pragma Assert (Present (Alias (Op)));
5751 Error_Msg_Sloc := Sloc (Alias (Op));
5752 Error_Msg_N ("\\inherited operation % with "
5753 & "convention % defined #", Typ);
5756 Error_Msg_Name_1 := Chars (Op);
5757 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5758 Error_Msg_Sloc := Sloc (Iface_Prim);
5759 Error_Msg_N ("\\overridden operation % with "
5760 & "convention % defined #", Typ);
5762 -- Avoid cascading errors
5767 Next_Elmt (Iface_Prim_Elmt);
5770 Next_Elmt (Iface_Elmt);
5772 end Check_Convention;
5776 Prim_Op : Entity_Id;
5777 Prim_Op_Elmt : Elmt_Id;
5779 -- Start of processing for Check_Conventions
5782 if not Has_Interfaces (Typ) then
5786 Collect_Interfaces (Typ, Ifaces_List);
5788 -- The algorithm checks every overriding dispatching operation against
5789 -- all the corresponding overridden dispatching operations, detecting
5790 -- differences in conventions.
5792 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5793 while Present (Prim_Op_Elmt) loop
5794 Prim_Op := Node (Prim_Op_Elmt);
5796 -- A small optimization: skip the predefined dispatching operations
5797 -- since they always have the same convention.
5799 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5800 Check_Convention (Prim_Op);
5803 Next_Elmt (Prim_Op_Elmt);
5805 end Check_Conventions;
5807 ------------------------------
5808 -- Check_Delayed_Subprogram --
5809 ------------------------------
5811 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5812 procedure Possible_Freeze (T : Entity_Id);
5813 -- T is the type of either a formal parameter or of the return type. If
5814 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5815 -- itself must be delayed.
5817 ---------------------
5818 -- Possible_Freeze --
5819 ---------------------
5821 procedure Possible_Freeze (T : Entity_Id) is
5822 Scop : constant Entity_Id := Scope (Designator);
5825 -- If the subprogram appears within a package instance (which may be
5826 -- the wrapper package of a subprogram instance) the freeze node for
5827 -- that package will freeze the subprogram at the proper place, so
5828 -- do not emit a freeze node for the subprogram, given that it may
5829 -- appear in the wrong scope.
5831 if Ekind (Scop) = E_Package
5832 and then not Comes_From_Source (Scop)
5833 and then Is_Generic_Instance (Scop)
5837 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5838 Set_Has_Delayed_Freeze (Designator);
5840 elsif Is_Access_Type (T)
5841 and then Has_Delayed_Freeze (Designated_Type (T))
5842 and then not Is_Frozen (Designated_Type (T))
5844 Set_Has_Delayed_Freeze (Designator);
5846 end Possible_Freeze;
5852 -- Start of processing for Check_Delayed_Subprogram
5855 -- All subprograms, including abstract subprograms, may need a freeze
5856 -- node if some formal type or the return type needs one.
5858 Possible_Freeze (Etype (Designator));
5859 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5861 -- Need delayed freeze if any of the formal types themselves need a
5862 -- delayed freeze and are not yet frozen.
5864 F := First_Formal (Designator);
5865 while Present (F) loop
5866 Possible_Freeze (Etype (F));
5867 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5871 -- Mark functions that return by reference. Note that it cannot be done
5872 -- for delayed_freeze subprograms because the underlying returned type
5873 -- may not be known yet (for private types).
5875 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5877 Typ : constant Entity_Id := Etype (Designator);
5878 Utyp : constant Entity_Id := Underlying_Type (Typ);
5881 if Is_Limited_View (Typ) then
5882 Set_Returns_By_Ref (Designator);
5884 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5885 Set_Returns_By_Ref (Designator);
5889 end Check_Delayed_Subprogram;
5891 ------------------------------------
5892 -- Check_Discriminant_Conformance --
5893 ------------------------------------
5895 procedure Check_Discriminant_Conformance
5900 Old_Discr : Entity_Id := First_Discriminant (Prev);
5901 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5902 New_Discr_Id : Entity_Id;
5903 New_Discr_Type : Entity_Id;
5905 procedure Conformance_Error (Msg : String; N : Node_Id);
5906 -- Post error message for conformance error on given node. Two messages
5907 -- are output. The first points to the previous declaration with a
5908 -- general "no conformance" message. The second is the detailed reason,
5909 -- supplied as Msg. The parameter N provide information for a possible
5910 -- & insertion in the message.
5912 -----------------------
5913 -- Conformance_Error --
5914 -----------------------
5916 procedure Conformance_Error (Msg : String; N : Node_Id) is
5918 Error_Msg_Sloc := Sloc (Prev_Loc);
5919 Error_Msg_N -- CODEFIX
5920 ("not fully conformant with declaration#!", N);
5921 Error_Msg_NE (Msg, N, N);
5922 end Conformance_Error;
5924 -- Start of processing for Check_Discriminant_Conformance
5927 while Present (Old_Discr) and then Present (New_Discr) loop
5928 New_Discr_Id := Defining_Identifier (New_Discr);
5930 -- The subtype mark of the discriminant on the full type has not
5931 -- been analyzed so we do it here. For an access discriminant a new
5934 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5936 Access_Definition (N, Discriminant_Type (New_Discr));
5939 Analyze (Discriminant_Type (New_Discr));
5940 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5942 -- Ada 2005: if the discriminant definition carries a null
5943 -- exclusion, create an itype to check properly for consistency
5944 -- with partial declaration.
5946 if Is_Access_Type (New_Discr_Type)
5947 and then Null_Exclusion_Present (New_Discr)
5950 Create_Null_Excluding_Itype
5951 (T => New_Discr_Type,
5952 Related_Nod => New_Discr,
5953 Scope_Id => Current_Scope);
5957 if not Conforming_Types
5958 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5960 Conformance_Error ("type of & does not match!", New_Discr_Id);
5963 -- Treat the new discriminant as an occurrence of the old one,
5964 -- for navigation purposes, and fill in some semantic
5965 -- information, for completeness.
5967 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5968 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5969 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5974 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5975 Conformance_Error ("name & does not match!", New_Discr_Id);
5979 -- Default expressions must match
5982 NewD : constant Boolean :=
5983 Present (Expression (New_Discr));
5984 OldD : constant Boolean :=
5985 Present (Expression (Parent (Old_Discr)));
5988 if NewD or OldD then
5990 -- The old default value has been analyzed and expanded,
5991 -- because the current full declaration will have frozen
5992 -- everything before. The new default values have not been
5993 -- expanded, so expand now to check conformance.
5996 Preanalyze_Spec_Expression
5997 (Expression (New_Discr), New_Discr_Type);
6000 if not (NewD and OldD)
6001 or else not Fully_Conformant_Expressions
6002 (Expression (Parent (Old_Discr)),
6003 Expression (New_Discr))
6007 ("default expression for & does not match!",
6014 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6016 if Ada_Version = Ada_83 then
6018 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6021 -- Grouping (use of comma in param lists) must be the same
6022 -- This is where we catch a misconformance like:
6025 -- A : Integer; B : Integer
6027 -- which are represented identically in the tree except
6028 -- for the setting of the flags More_Ids and Prev_Ids.
6030 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6031 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6034 ("grouping of & does not match!", New_Discr_Id);
6040 Next_Discriminant (Old_Discr);
6044 if Present (Old_Discr) then
6045 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6048 elsif Present (New_Discr) then
6050 ("too many discriminants!", Defining_Identifier (New_Discr));
6053 end Check_Discriminant_Conformance;
6055 ----------------------------
6056 -- Check_Fully_Conformant --
6057 ----------------------------
6059 procedure Check_Fully_Conformant
6060 (New_Id : Entity_Id;
6062 Err_Loc : Node_Id := Empty)
6065 pragma Warnings (Off, Result);
6068 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6069 end Check_Fully_Conformant;
6071 --------------------------
6072 -- Check_Limited_Return --
6073 --------------------------
6075 procedure Check_Limited_Return
6081 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6082 -- replaced by anonymous access results. This is an incompatibility with
6083 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6084 -- controllable with special switch. ???
6086 -- A limited interface that is not immutably limited is OK
6088 if Is_Limited_Interface (R_Type)
6090 not (Is_Task_Interface (R_Type)
6091 or else Is_Protected_Interface (R_Type)
6092 or else Is_Synchronized_Interface (R_Type))
6096 elsif Is_Limited_Type (R_Type)
6097 and then not Is_Interface (R_Type)
6098 and then Comes_From_Source (N)
6099 and then not In_Instance_Body
6100 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6102 -- Error in Ada 2005
6104 if Ada_Version >= Ada_2005
6105 and then not Debug_Flag_Dot_L
6106 and then not GNAT_Mode
6109 ("(Ada 2005) cannot copy object of a limited type "
6110 & "(RM-2005 6.5(5.5/2))", Expr);
6112 if Is_Limited_View (R_Type) then
6114 ("\return by reference not permitted in Ada 2005", Expr);
6117 -- Warn in Ada 95 mode, to give folks a heads up about this
6120 -- In GNAT mode, this is just a warning, to allow it to be evilly
6121 -- turned off. Otherwise it is a real error.
6123 -- In a generic context, simplify the warning because it makes no
6124 -- sense to discuss pass-by-reference or copy.
6126 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6127 if Inside_A_Generic then
6129 ("return of limited object not permitted in Ada 2005 "
6130 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6132 elsif Is_Limited_View (R_Type) then
6134 ("return by reference not permitted in Ada 2005 "
6135 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6138 ("cannot copy object of a limited type in Ada 2005 "
6139 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6142 -- Ada 95 mode, and compatibility warnings disabled
6145 pragma Assert (Ada_Version <= Ada_95);
6146 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6147 return; -- skip continuation messages below
6150 if not Inside_A_Generic then
6152 ("\consider switching to return of access type", Expr);
6153 Explain_Limited_Type (R_Type, Expr);
6156 end Check_Limited_Return;
6158 ---------------------------
6159 -- Check_Mode_Conformant --
6160 ---------------------------
6162 procedure Check_Mode_Conformant
6163 (New_Id : Entity_Id;
6165 Err_Loc : Node_Id := Empty;
6166 Get_Inst : Boolean := False)
6169 pragma Warnings (Off, Result);
6172 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6173 end Check_Mode_Conformant;
6175 --------------------------------
6176 -- Check_Overriding_Indicator --
6177 --------------------------------
6179 procedure Check_Overriding_Indicator
6181 Overridden_Subp : Entity_Id;
6182 Is_Primitive : Boolean)
6188 -- No overriding indicator for literals
6190 if Ekind (Subp) = E_Enumeration_Literal then
6193 elsif Ekind (Subp) = E_Entry then
6194 Decl := Parent (Subp);
6196 -- No point in analyzing a malformed operator
6198 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6199 and then Error_Posted (Subp)
6204 Decl := Unit_Declaration_Node (Subp);
6207 if Nkind_In (Decl, N_Subprogram_Body,
6208 N_Subprogram_Body_Stub,
6209 N_Subprogram_Declaration,
6210 N_Abstract_Subprogram_Declaration,
6211 N_Subprogram_Renaming_Declaration)
6213 Spec := Specification (Decl);
6215 elsif Nkind (Decl) = N_Entry_Declaration then
6222 -- The overriding operation is type conformant with the overridden one,
6223 -- but the names of the formals are not required to match. If the names
6224 -- appear permuted in the overriding operation, this is a possible
6225 -- source of confusion that is worth diagnosing. Controlling formals
6226 -- often carry names that reflect the type, and it is not worthwhile
6227 -- requiring that their names match.
6229 if Present (Overridden_Subp)
6230 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6237 Form1 := First_Formal (Subp);
6238 Form2 := First_Formal (Overridden_Subp);
6240 -- If the overriding operation is a synchronized operation, skip
6241 -- the first parameter of the overridden operation, which is
6242 -- implicit in the new one. If the operation is declared in the
6243 -- body it is not primitive and all formals must match.
6245 if Is_Concurrent_Type (Scope (Subp))
6246 and then Is_Tagged_Type (Scope (Subp))
6247 and then not Has_Completion (Scope (Subp))
6249 Form2 := Next_Formal (Form2);
6252 if Present (Form1) then
6253 Form1 := Next_Formal (Form1);
6254 Form2 := Next_Formal (Form2);
6257 while Present (Form1) loop
6258 if not Is_Controlling_Formal (Form1)
6259 and then Present (Next_Formal (Form2))
6260 and then Chars (Form1) = Chars (Next_Formal (Form2))
6262 Error_Msg_Node_2 := Alias (Overridden_Subp);
6263 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6265 ("& does not match corresponding formal of&#",
6270 Next_Formal (Form1);
6271 Next_Formal (Form2);
6276 -- If there is an overridden subprogram, then check that there is no
6277 -- "not overriding" indicator, and mark the subprogram as overriding.
6278 -- This is not done if the overridden subprogram is marked as hidden,
6279 -- which can occur for the case of inherited controlled operations
6280 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6281 -- subprogram is not itself hidden. (Note: This condition could probably
6282 -- be simplified, leaving out the testing for the specific controlled
6283 -- cases, but it seems safer and clearer this way, and echoes similar
6284 -- special-case tests of this kind in other places.)
6286 if Present (Overridden_Subp)
6287 and then (not Is_Hidden (Overridden_Subp)
6289 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6292 and then Present (Alias (Overridden_Subp))
6293 and then not Is_Hidden (Alias (Overridden_Subp))))
6295 if Must_Not_Override (Spec) then
6296 Error_Msg_Sloc := Sloc (Overridden_Subp);
6298 if Ekind (Subp) = E_Entry then
6300 ("entry & overrides inherited operation #", Spec, Subp);
6303 ("subprogram & overrides inherited operation #", Spec, Subp);
6306 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6307 -- as an extension of Root_Controlled, and thus has a useless Adjust
6308 -- operation. This operation should not be inherited by other limited
6309 -- controlled types. An explicit Adjust for them is not overriding.
6311 elsif Must_Override (Spec)
6312 and then Chars (Overridden_Subp) = Name_Adjust
6313 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6314 and then Present (Alias (Overridden_Subp))
6315 and then In_Predefined_Unit (Alias (Overridden_Subp))
6318 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6319 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6321 elsif Is_Subprogram (Subp) then
6322 if Is_Init_Proc (Subp) then
6325 elsif No (Overridden_Operation (Subp)) then
6327 -- For entities generated by Derive_Subprograms the overridden
6328 -- operation is the inherited primitive (which is available
6329 -- through the attribute alias)
6331 if (Is_Dispatching_Operation (Subp)
6332 or else Is_Dispatching_Operation (Overridden_Subp))
6333 and then not Comes_From_Source (Overridden_Subp)
6334 and then Find_Dispatching_Type (Overridden_Subp) =
6335 Find_Dispatching_Type (Subp)
6336 and then Present (Alias (Overridden_Subp))
6337 and then Comes_From_Source (Alias (Overridden_Subp))
6339 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6340 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6343 Set_Overridden_Operation (Subp, Overridden_Subp);
6344 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6349 -- If primitive flag is set or this is a protected operation, then
6350 -- the operation is overriding at the point of its declaration, so
6351 -- warn if necessary. Otherwise it may have been declared before the
6352 -- operation it overrides and no check is required.
6355 and then not Must_Override (Spec)
6356 and then (Is_Primitive
6357 or else Ekind (Scope (Subp)) = E_Protected_Type)
6359 Style.Missing_Overriding (Decl, Subp);
6362 -- If Subp is an operator, it may override a predefined operation, if
6363 -- it is defined in the same scope as the type to which it applies.
6364 -- In that case Overridden_Subp is empty because of our implicit
6365 -- representation for predefined operators. We have to check whether the
6366 -- signature of Subp matches that of a predefined operator. Note that
6367 -- first argument provides the name of the operator, and the second
6368 -- argument the signature that may match that of a standard operation.
6369 -- If the indicator is overriding, then the operator must match a
6370 -- predefined signature, because we know already that there is no
6371 -- explicit overridden operation.
6373 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6374 if Must_Not_Override (Spec) then
6376 -- If this is not a primitive or a protected subprogram, then
6377 -- "not overriding" is illegal.
6380 and then Ekind (Scope (Subp)) /= E_Protected_Type
6382 Error_Msg_N ("overriding indicator only allowed "
6383 & "if subprogram is primitive", Subp);
6385 elsif Can_Override_Operator (Subp) then
6387 ("subprogram& overrides predefined operator ", Spec, Subp);
6390 elsif Must_Override (Spec) then
6391 if No (Overridden_Operation (Subp))
6392 and then not Can_Override_Operator (Subp)
6394 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6397 elsif not Error_Posted (Subp)
6398 and then Style_Check
6399 and then Can_Override_Operator (Subp)
6400 and then not In_Predefined_Unit (Subp)
6402 -- If style checks are enabled, indicate that the indicator is
6403 -- missing. However, at the point of declaration, the type of
6404 -- which this is a primitive operation may be private, in which
6405 -- case the indicator would be premature.
6407 if Has_Private_Declaration (Etype (Subp))
6408 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6412 Style.Missing_Overriding (Decl, Subp);
6416 elsif Must_Override (Spec) then
6417 if Ekind (Subp) = E_Entry then
6418 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6420 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6423 -- If the operation is marked "not overriding" and it's not primitive
6424 -- then an error is issued, unless this is an operation of a task or
6425 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6426 -- has been specified have already been checked above.
6428 elsif Must_Not_Override (Spec)
6429 and then not Is_Primitive
6430 and then Ekind (Subp) /= E_Entry
6431 and then Ekind (Scope (Subp)) /= E_Protected_Type
6434 ("overriding indicator only allowed if subprogram is primitive",
6438 end Check_Overriding_Indicator;
6444 -- Note: this procedure needs to know far too much about how the expander
6445 -- messes with exceptions. The use of the flag Exception_Junk and the
6446 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6447 -- works, but is not very clean. It would be better if the expansion
6448 -- routines would leave Original_Node working nicely, and we could use
6449 -- Original_Node here to ignore all the peculiar expander messing ???
6451 procedure Check_Returns
6455 Proc : Entity_Id := Empty)
6459 procedure Check_Statement_Sequence (L : List_Id);
6460 -- Internal recursive procedure to check a list of statements for proper
6461 -- termination by a return statement (or a transfer of control or a
6462 -- compound statement that is itself internally properly terminated).
6464 ------------------------------
6465 -- Check_Statement_Sequence --
6466 ------------------------------
6468 procedure Check_Statement_Sequence (L : List_Id) is
6473 function Assert_False return Boolean;
6474 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6475 -- rewritten as a null statement when assertions are off. The assert
6476 -- is not active, but it is still enough to kill the warning.
6482 function Assert_False return Boolean is
6483 Orig : constant Node_Id := Original_Node (Last_Stm);
6486 if Nkind (Orig) = N_Pragma
6487 and then Pragma_Name (Orig) = Name_Assert
6488 and then not Error_Posted (Orig)
6491 Arg : constant Node_Id :=
6492 First (Pragma_Argument_Associations (Orig));
6493 Exp : constant Node_Id := Expression (Arg);
6495 return Nkind (Exp) = N_Identifier
6496 and then Chars (Exp) = Name_False;
6506 Raise_Exception_Call : Boolean;
6507 -- Set True if statement sequence terminated by Raise_Exception call
6508 -- or a Reraise_Occurrence call.
6510 -- Start of processing for Check_Statement_Sequence
6513 Raise_Exception_Call := False;
6515 -- Get last real statement
6517 Last_Stm := Last (L);
6519 -- Deal with digging out exception handler statement sequences that
6520 -- have been transformed by the local raise to goto optimization.
6521 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6522 -- optimization has occurred, we are looking at something like:
6525 -- original stmts in block
6529 -- goto L1; | omitted if No_Exception_Propagation
6534 -- goto L3; -- skip handler when exception not raised
6536 -- <<L1>> -- target label for local exception
6550 -- and what we have to do is to dig out the estmts1 and estmts2
6551 -- sequences (which were the original sequences of statements in
6552 -- the exception handlers) and check them.
6554 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6559 exit when Nkind (Stm) /= N_Block_Statement;
6560 exit when not Exception_Junk (Stm);
6563 exit when Nkind (Stm) /= N_Label;
6564 exit when not Exception_Junk (Stm);
6565 Check_Statement_Sequence
6566 (Statements (Handled_Statement_Sequence (Next (Stm))));
6571 exit when Nkind (Stm) /= N_Goto_Statement;
6572 exit when not Exception_Junk (Stm);
6576 -- Don't count pragmas
6578 while Nkind (Last_Stm) = N_Pragma
6580 -- Don't count call to SS_Release (can happen after Raise_Exception)
6583 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6585 Nkind (Name (Last_Stm)) = N_Identifier
6587 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6589 -- Don't count exception junk
6592 (Nkind_In (Last_Stm, N_Goto_Statement,
6594 N_Object_Declaration)
6595 and then Exception_Junk (Last_Stm))
6596 or else Nkind (Last_Stm) in N_Push_xxx_Label
6597 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6599 -- Inserted code, such as finalization calls, is irrelevant: we only
6600 -- need to check original source.
6602 or else Is_Rewrite_Insertion (Last_Stm)
6607 -- Here we have the "real" last statement
6609 Kind := Nkind (Last_Stm);
6611 -- Transfer of control, OK. Note that in the No_Return procedure
6612 -- case, we already diagnosed any explicit return statements, so
6613 -- we can treat them as OK in this context.
6615 if Is_Transfer (Last_Stm) then
6618 -- Check cases of explicit non-indirect procedure calls
6620 elsif Kind = N_Procedure_Call_Statement
6621 and then Is_Entity_Name (Name (Last_Stm))
6623 -- Check call to Raise_Exception procedure which is treated
6624 -- specially, as is a call to Reraise_Occurrence.
6626 -- We suppress the warning in these cases since it is likely that
6627 -- the programmer really does not expect to deal with the case
6628 -- of Null_Occurrence, and thus would find a warning about a
6629 -- missing return curious, and raising Program_Error does not
6630 -- seem such a bad behavior if this does occur.
6632 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6633 -- behavior will be to raise Constraint_Error (see AI-329).
6635 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6637 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6639 Raise_Exception_Call := True;
6641 -- For Raise_Exception call, test first argument, if it is
6642 -- an attribute reference for a 'Identity call, then we know
6643 -- that the call cannot possibly return.
6646 Arg : constant Node_Id :=
6647 Original_Node (First_Actual (Last_Stm));
6649 if Nkind (Arg) = N_Attribute_Reference
6650 and then Attribute_Name (Arg) = Name_Identity
6657 -- If statement, need to look inside if there is an else and check
6658 -- each constituent statement sequence for proper termination.
6660 elsif Kind = N_If_Statement
6661 and then Present (Else_Statements (Last_Stm))
6663 Check_Statement_Sequence (Then_Statements (Last_Stm));
6664 Check_Statement_Sequence (Else_Statements (Last_Stm));
6666 if Present (Elsif_Parts (Last_Stm)) then
6668 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6671 while Present (Elsif_Part) loop
6672 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6680 -- Case statement, check each case for proper termination
6682 elsif Kind = N_Case_Statement then
6686 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6687 while Present (Case_Alt) loop
6688 Check_Statement_Sequence (Statements (Case_Alt));
6689 Next_Non_Pragma (Case_Alt);
6695 -- Block statement, check its handled sequence of statements
6697 elsif Kind = N_Block_Statement then
6703 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6712 -- Loop statement. If there is an iteration scheme, we can definitely
6713 -- fall out of the loop. Similarly if there is an exit statement, we
6714 -- can fall out. In either case we need a following return.
6716 elsif Kind = N_Loop_Statement then
6717 if Present (Iteration_Scheme (Last_Stm))
6718 or else Has_Exit (Entity (Identifier (Last_Stm)))
6722 -- A loop with no exit statement or iteration scheme is either
6723 -- an infinite loop, or it has some other exit (raise/return).
6724 -- In either case, no warning is required.
6730 -- Timed entry call, check entry call and delay alternatives
6732 -- Note: in expanded code, the timed entry call has been converted
6733 -- to a set of expanded statements on which the check will work
6734 -- correctly in any case.
6736 elsif Kind = N_Timed_Entry_Call then
6738 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6739 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6742 -- If statement sequence of entry call alternative is missing,
6743 -- then we can definitely fall through, and we post the error
6744 -- message on the entry call alternative itself.
6746 if No (Statements (ECA)) then
6749 -- If statement sequence of delay alternative is missing, then
6750 -- we can definitely fall through, and we post the error
6751 -- message on the delay alternative itself.
6753 -- Note: if both ECA and DCA are missing the return, then we
6754 -- post only one message, should be enough to fix the bugs.
6755 -- If not we will get a message next time on the DCA when the
6758 elsif No (Statements (DCA)) then
6761 -- Else check both statement sequences
6764 Check_Statement_Sequence (Statements (ECA));
6765 Check_Statement_Sequence (Statements (DCA));
6770 -- Conditional entry call, check entry call and else part
6772 -- Note: in expanded code, the conditional entry call has been
6773 -- converted to a set of expanded statements on which the check
6774 -- will work correctly in any case.
6776 elsif Kind = N_Conditional_Entry_Call then
6778 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6781 -- If statement sequence of entry call alternative is missing,
6782 -- then we can definitely fall through, and we post the error
6783 -- message on the entry call alternative itself.
6785 if No (Statements (ECA)) then
6788 -- Else check statement sequence and else part
6791 Check_Statement_Sequence (Statements (ECA));
6792 Check_Statement_Sequence (Else_Statements (Last_Stm));
6798 -- If we fall through, issue appropriate message
6802 -- Kill warning if last statement is a raise exception call,
6803 -- or a pragma Assert (False). Note that with assertions enabled,
6804 -- such a pragma has been converted into a raise exception call
6805 -- already, so the Assert_False is for the assertions off case.
6807 if not Raise_Exception_Call and then not Assert_False then
6809 -- In GNATprove mode, it is an error to have a missing return
6811 Error_Msg_Warn := SPARK_Mode /= On;
6813 -- Issue error message or warning
6816 ("RETURN statement missing following this statement<<!",
6819 ("\Program_Error ]<<!", Last_Stm);
6822 -- Note: we set Err even though we have not issued a warning
6823 -- because we still have a case of a missing return. This is
6824 -- an extremely marginal case, probably will never be noticed
6825 -- but we might as well get it right.
6829 -- Otherwise we have the case of a procedure marked No_Return
6832 if not Raise_Exception_Call then
6833 if GNATprove_Mode then
6835 ("implied return after this statement would have raised "
6836 & "Program_Error", Last_Stm);
6838 -- In normal compilation mode, do not warn on a generated call
6839 -- (e.g. in the body of a renaming as completion).
6841 elsif Comes_From_Source (Last_Stm) then
6843 ("implied return after this statement will raise "
6844 & "Program_Error??", Last_Stm);
6847 Error_Msg_Warn := SPARK_Mode /= On;
6849 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6853 RE : constant Node_Id :=
6854 Make_Raise_Program_Error (Sloc (Last_Stm),
6855 Reason => PE_Implicit_Return);
6857 Insert_After (Last_Stm, RE);
6861 end Check_Statement_Sequence;
6863 -- Start of processing for Check_Returns
6867 Check_Statement_Sequence (Statements (HSS));
6869 if Present (Exception_Handlers (HSS)) then
6870 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6871 while Present (Handler) loop
6872 Check_Statement_Sequence (Statements (Handler));
6873 Next_Non_Pragma (Handler);
6878 ----------------------------
6879 -- Check_Subprogram_Order --
6880 ----------------------------
6882 procedure Check_Subprogram_Order (N : Node_Id) is
6884 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6885 -- This is used to check if S1 > S2 in the sense required by this test,
6886 -- for example nameab < namec, but name2 < name10.
6888 -----------------------------
6889 -- Subprogram_Name_Greater --
6890 -----------------------------
6892 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6897 -- Deal with special case where names are identical except for a
6898 -- numerical suffix. These are handled specially, taking the numeric
6899 -- ordering from the suffix into account.
6902 while S1 (L1) in '0' .. '9' loop
6907 while S2 (L2) in '0' .. '9' loop
6911 -- If non-numeric parts non-equal, do straight compare
6913 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6916 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6917 -- that a missing suffix is treated as numeric zero in this test.
6921 while L1 < S1'Last loop
6923 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6927 while L2 < S2'Last loop
6929 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6934 end Subprogram_Name_Greater;
6936 -- Start of processing for Check_Subprogram_Order
6939 -- Check body in alpha order if this is option
6942 and then Style_Check_Order_Subprograms
6943 and then Nkind (N) = N_Subprogram_Body
6944 and then Comes_From_Source (N)
6945 and then In_Extended_Main_Source_Unit (N)
6949 renames Scope_Stack.Table
6950 (Scope_Stack.Last).Last_Subprogram_Name;
6952 Body_Id : constant Entity_Id :=
6953 Defining_Entity (Specification (N));
6956 Get_Decoded_Name_String (Chars (Body_Id));
6959 if Subprogram_Name_Greater
6960 (LSN.all, Name_Buffer (1 .. Name_Len))
6962 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6968 LSN := new String'(Name_Buffer (1 .. Name_Len));
6971 end Check_Subprogram_Order;
6973 ------------------------------
6974 -- Check_Subtype_Conformant --
6975 ------------------------------
6977 procedure Check_Subtype_Conformant
6978 (New_Id : Entity_Id;
6980 Err_Loc : Node_Id := Empty;
6981 Skip_Controlling_Formals : Boolean := False;
6982 Get_Inst : Boolean := False)
6985 pragma Warnings (Off, Result);
6988 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6989 Skip_Controlling_Formals => Skip_Controlling_Formals,
6990 Get_Inst => Get_Inst);
6991 end Check_Subtype_Conformant;
6993 -----------------------------------
6994 -- Check_Synchronized_Overriding --
6995 -----------------------------------
6997 procedure Check_Synchronized_Overriding
6998 (Def_Id : Entity_Id;
6999 Overridden_Subp : out Entity_Id)
7001 Ifaces_List : Elist_Id;
7005 function Matches_Prefixed_View_Profile
7006 (Prim_Params : List_Id;
7007 Iface_Params : List_Id) return Boolean;
7008 -- Determine whether a subprogram's parameter profile Prim_Params
7009 -- matches that of a potentially overridden interface subprogram
7010 -- Iface_Params. Also determine if the type of first parameter of
7011 -- Iface_Params is an implemented interface.
7013 -----------------------------------
7014 -- Matches_Prefixed_View_Profile --
7015 -----------------------------------
7017 function Matches_Prefixed_View_Profile
7018 (Prim_Params : List_Id;
7019 Iface_Params : List_Id) return Boolean
7021 function Is_Implemented
7022 (Ifaces_List : Elist_Id;
7023 Iface : Entity_Id) return Boolean;
7024 -- Determine if Iface is implemented by the current task or
7027 --------------------
7028 -- Is_Implemented --
7029 --------------------
7031 function Is_Implemented
7032 (Ifaces_List : Elist_Id;
7033 Iface : Entity_Id) return Boolean
7035 Iface_Elmt : Elmt_Id;
7038 Iface_Elmt := First_Elmt (Ifaces_List);
7039 while Present (Iface_Elmt) loop
7040 if Node (Iface_Elmt) = Iface then
7044 Next_Elmt (Iface_Elmt);
7052 Iface_Id : Entity_Id;
7053 Iface_Param : Node_Id;
7054 Iface_Typ : Entity_Id;
7055 Prim_Id : Entity_Id;
7056 Prim_Param : Node_Id;
7057 Prim_Typ : Entity_Id;
7059 -- Start of processing for Matches_Prefixed_View_Profile
7062 Iface_Param := First (Iface_Params);
7063 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7065 if Is_Access_Type (Iface_Typ) then
7066 Iface_Typ := Designated_Type (Iface_Typ);
7069 Prim_Param := First (Prim_Params);
7071 -- The first parameter of the potentially overridden subprogram must
7072 -- be an interface implemented by Prim.
7074 if not Is_Interface (Iface_Typ)
7075 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7080 -- The checks on the object parameters are done, so move on to the
7081 -- rest of the parameters.
7083 if not In_Scope then
7084 Prim_Param := Next (Prim_Param);
7087 Iface_Param := Next (Iface_Param);
7088 while Present (Iface_Param) and then Present (Prim_Param) loop
7089 Iface_Id := Defining_Identifier (Iface_Param);
7090 Iface_Typ := Find_Parameter_Type (Iface_Param);
7092 Prim_Id := Defining_Identifier (Prim_Param);
7093 Prim_Typ := Find_Parameter_Type (Prim_Param);
7095 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7096 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7097 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7099 Iface_Typ := Designated_Type (Iface_Typ);
7100 Prim_Typ := Designated_Type (Prim_Typ);
7103 -- Case of multiple interface types inside a parameter profile
7105 -- (Obj_Param : in out Iface; ...; Param : Iface)
7107 -- If the interface type is implemented, then the matching type in
7108 -- the primitive should be the implementing record type.
7110 if Ekind (Iface_Typ) = E_Record_Type
7111 and then Is_Interface (Iface_Typ)
7112 and then Is_Implemented (Ifaces_List, Iface_Typ)
7114 if Prim_Typ /= Typ then
7118 -- The two parameters must be both mode and subtype conformant
7120 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7122 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7131 -- One of the two lists contains more parameters than the other
7133 if Present (Iface_Param) or else Present (Prim_Param) then
7138 end Matches_Prefixed_View_Profile;
7140 -- Start of processing for Check_Synchronized_Overriding
7143 Overridden_Subp := Empty;
7145 -- Def_Id must be an entry or a subprogram. We should skip predefined
7146 -- primitives internally generated by the front end; however at this
7147 -- stage predefined primitives are still not fully decorated. As a
7148 -- minor optimization we skip here internally generated subprograms.
7150 if (Ekind (Def_Id) /= E_Entry
7151 and then Ekind (Def_Id) /= E_Function
7152 and then Ekind (Def_Id) /= E_Procedure)
7153 or else not Comes_From_Source (Def_Id)
7158 -- Search for the concurrent declaration since it contains the list of
7159 -- all implemented interfaces. In this case, the subprogram is declared
7160 -- within the scope of a protected or a task type.
7162 if Present (Scope (Def_Id))
7163 and then Is_Concurrent_Type (Scope (Def_Id))
7164 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7166 Typ := Scope (Def_Id);
7169 -- The enclosing scope is not a synchronized type and the subprogram
7172 elsif No (First_Formal (Def_Id)) then
7175 -- The subprogram has formals and hence it may be a primitive of a
7179 Typ := Etype (First_Formal (Def_Id));
7181 if Is_Access_Type (Typ) then
7182 Typ := Directly_Designated_Type (Typ);
7185 if Is_Concurrent_Type (Typ)
7186 and then not Is_Generic_Actual_Type (Typ)
7190 -- This case occurs when the concurrent type is declared within a
7191 -- generic unit. As a result the corresponding record has been built
7192 -- and used as the type of the first formal, we just have to retrieve
7193 -- the corresponding concurrent type.
7195 elsif Is_Concurrent_Record_Type (Typ)
7196 and then not Is_Class_Wide_Type (Typ)
7197 and then Present (Corresponding_Concurrent_Type (Typ))
7199 Typ := Corresponding_Concurrent_Type (Typ);
7207 -- There is no overriding to check if this is an inherited operation in
7208 -- a type derivation for a generic actual.
7210 Collect_Interfaces (Typ, Ifaces_List);
7212 if Is_Empty_Elmt_List (Ifaces_List) then
7216 -- Determine whether entry or subprogram Def_Id overrides a primitive
7217 -- operation that belongs to one of the interfaces in Ifaces_List.
7220 Candidate : Entity_Id := Empty;
7221 Hom : Entity_Id := Empty;
7222 Subp : Entity_Id := Empty;
7225 -- Traverse the homonym chain, looking for a potentially overridden
7226 -- subprogram that belongs to an implemented interface.
7228 Hom := Current_Entity_In_Scope (Def_Id);
7229 while Present (Hom) loop
7233 or else not Is_Overloadable (Subp)
7234 or else not Is_Primitive (Subp)
7235 or else not Is_Dispatching_Operation (Subp)
7236 or else not Present (Find_Dispatching_Type (Subp))
7237 or else not Is_Interface (Find_Dispatching_Type (Subp))
7241 -- Entries and procedures can override abstract or null interface
7244 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7245 and then Ekind (Subp) = E_Procedure
7246 and then Matches_Prefixed_View_Profile
7247 (Parameter_Specifications (Parent (Def_Id)),
7248 Parameter_Specifications (Parent (Subp)))
7252 -- For an overridden subprogram Subp, check whether the mode
7253 -- of its first parameter is correct depending on the kind of
7254 -- synchronized type.
7257 Formal : constant Node_Id := First_Formal (Candidate);
7260 -- In order for an entry or a protected procedure to
7261 -- override, the first parameter of the overridden routine
7262 -- must be of mode "out", "in out", or access-to-variable.
7264 if Ekind_In (Candidate, E_Entry, E_Procedure)
7265 and then Is_Protected_Type (Typ)
7266 and then Ekind (Formal) /= E_In_Out_Parameter
7267 and then Ekind (Formal) /= E_Out_Parameter
7268 and then Nkind (Parameter_Type (Parent (Formal))) /=
7273 -- All other cases are OK since a task entry or routine does
7274 -- not have a restriction on the mode of the first parameter
7275 -- of the overridden interface routine.
7278 Overridden_Subp := Candidate;
7283 -- Functions can override abstract interface functions. Return
7284 -- types must be subtype conformant.
7286 elsif Ekind (Def_Id) = E_Function
7287 and then Ekind (Subp) = E_Function
7288 and then Matches_Prefixed_View_Profile
7289 (Parameter_Specifications (Parent (Def_Id)),
7290 Parameter_Specifications (Parent (Subp)))
7291 and then Conforming_Types
7292 (Etype (Def_Id), Etype (Subp), Subtype_Conformant)
7296 -- If an inherited subprogram is implemented by a protected
7297 -- function, then the first parameter of the inherited
7298 -- subprogram shall be of mode in, but not an access-to-
7299 -- variable parameter (RM 9.4(11/9)).
7301 if Present (First_Formal (Subp))
7302 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7304 (not Is_Access_Type (Etype (First_Formal (Subp)))
7306 Is_Access_Constant (Etype (First_Formal (Subp))))
7308 Overridden_Subp := Subp;
7313 Hom := Homonym (Hom);
7316 -- After examining all candidates for overriding, we are left with
7317 -- the best match, which is a mode-incompatible interface routine.
7319 if In_Scope and then Present (Candidate) then
7320 Error_Msg_PT (Def_Id, Candidate);
7323 Overridden_Subp := Candidate;
7326 end Check_Synchronized_Overriding;
7328 ---------------------------
7329 -- Check_Type_Conformant --
7330 ---------------------------
7332 procedure Check_Type_Conformant
7333 (New_Id : Entity_Id;
7335 Err_Loc : Node_Id := Empty)
7338 pragma Warnings (Off, Result);
7341 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7342 end Check_Type_Conformant;
7344 ---------------------------
7345 -- Can_Override_Operator --
7346 ---------------------------
7348 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7352 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7356 Typ := Base_Type (Etype (First_Formal (Subp)));
7358 -- Check explicitly that the operation is a primitive of the type
7360 return Operator_Matches_Spec (Subp, Subp)
7361 and then not Is_Generic_Type (Typ)
7362 and then Scope (Subp) = Scope (Typ)
7363 and then not Is_Class_Wide_Type (Typ);
7365 end Can_Override_Operator;
7367 ----------------------
7368 -- Conforming_Types --
7369 ----------------------
7371 function Conforming_Types
7374 Ctype : Conformance_Type;
7375 Get_Inst : Boolean := False) return Boolean
7377 function Base_Types_Match
7379 Typ_2 : Entity_Id) return Boolean;
7380 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7381 -- in different scopes (e.g. parent and child instances), then verify
7382 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7383 -- the same subtype chain. The whole purpose of this procedure is to
7384 -- prevent spurious ambiguities in an instantiation that may arise if
7385 -- two distinct generic types are instantiated with the same actual.
7387 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7388 -- An access parameter can designate an incomplete type. If the
7389 -- incomplete type is the limited view of a type from a limited_
7390 -- with_clause, check whether the non-limited view is available.
7391 -- If it is a (non-limited) incomplete type, get the full view.
7393 function Matches_Limited_With_View
7395 Typ_2 : Entity_Id) return Boolean;
7396 -- Returns True if and only if either Typ_1 denotes a limited view of
7397 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7398 -- the limited with view of a type is used in a subprogram declaration
7399 -- and the subprogram body is in the scope of a regular with clause for
7400 -- the same unit. In such a case, the two type entities are considered
7401 -- identical for purposes of conformance checking.
7403 ----------------------
7404 -- Base_Types_Match --
7405 ----------------------
7407 function Base_Types_Match
7409 Typ_2 : Entity_Id) return Boolean
7411 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7412 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7415 if Typ_1 = Typ_2 then
7418 elsif Base_1 = Base_2 then
7420 -- The following is too permissive. A more precise test should
7421 -- check that the generic actual is an ancestor subtype of the
7424 -- See code in Find_Corresponding_Spec that applies an additional
7425 -- filter to handle accidental amiguities in instances.
7428 not Is_Generic_Actual_Type (Typ_1)
7429 or else not Is_Generic_Actual_Type (Typ_2)
7430 or else Scope (Typ_1) /= Scope (Typ_2);
7432 -- If Typ_2 is a generic actual type it is declared as the subtype of
7433 -- the actual. If that actual is itself a subtype we need to use its
7434 -- own base type to check for compatibility.
7436 elsif Ekind (Base_2) = Ekind (Typ_2)
7437 and then Base_1 = Base_Type (Base_2)
7441 elsif Ekind (Base_1) = Ekind (Typ_1)
7442 and then Base_2 = Base_Type (Base_1)
7449 end Base_Types_Match;
7451 --------------------------
7452 -- Find_Designated_Type --
7453 --------------------------
7455 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7459 Desig := Directly_Designated_Type (Typ);
7461 if Ekind (Desig) = E_Incomplete_Type then
7463 -- If regular incomplete type, get full view if available
7465 if Present (Full_View (Desig)) then
7466 Desig := Full_View (Desig);
7468 -- If limited view of a type, get non-limited view if available,
7469 -- and check again for a regular incomplete type.
7471 elsif Present (Non_Limited_View (Desig)) then
7472 Desig := Get_Full_View (Non_Limited_View (Desig));
7477 end Find_Designated_Type;
7479 -------------------------------
7480 -- Matches_Limited_With_View --
7481 -------------------------------
7483 function Matches_Limited_With_View
7485 Typ_2 : Entity_Id) return Boolean
7487 function Is_Matching_Limited_View
7489 View : Entity_Id) return Boolean;
7490 -- Determine whether non-limited view View denotes type Typ in some
7491 -- conformant fashion.
7493 ------------------------------
7494 -- Is_Matching_Limited_View --
7495 ------------------------------
7497 function Is_Matching_Limited_View
7499 View : Entity_Id) return Boolean
7501 Root_Typ : Entity_Id;
7502 Root_View : Entity_Id;
7505 -- The non-limited view directly denotes the type
7510 -- The type is a subtype of the non-limited view
7512 elsif Is_Subtype_Of (Typ, View) then
7515 -- Both the non-limited view and the type denote class-wide types
7517 elsif Is_Class_Wide_Type (Typ)
7518 and then Is_Class_Wide_Type (View)
7520 Root_Typ := Root_Type (Typ);
7521 Root_View := Root_Type (View);
7523 if Root_Typ = Root_View then
7526 -- An incomplete tagged type and its full view may receive two
7527 -- distinct class-wide types when the related package has not
7528 -- been analyzed yet.
7531 -- type T is tagged; -- CW_1
7532 -- type T is tagged null record; -- CW_2
7535 -- This is because the package lacks any semantic information
7536 -- that may eventually link both views of T. As a consequence,
7537 -- a client of the limited view of Pack will see CW_2 while a
7538 -- client of the non-limited view of Pack will see CW_1.
7540 elsif Is_Incomplete_Type (Root_Typ)
7541 and then Present (Full_View (Root_Typ))
7542 and then Full_View (Root_Typ) = Root_View
7546 elsif Is_Incomplete_Type (Root_View)
7547 and then Present (Full_View (Root_View))
7548 and then Full_View (Root_View) = Root_Typ
7555 end Is_Matching_Limited_View;
7557 -- Start of processing for Matches_Limited_With_View
7560 -- In some cases a type imported through a limited_with clause, and
7561 -- its non-limited view are both visible, for example in an anonymous
7562 -- access-to-class-wide type in a formal, or when building the body
7563 -- for a subprogram renaming after the subprogram has been frozen.
7564 -- In these cases both entities designate the same type. In addition,
7565 -- if one of them is an actual in an instance, it may be a subtype of
7566 -- the non-limited view of the other.
7568 if From_Limited_With (Typ_1)
7569 and then From_Limited_With (Typ_2)
7570 and then Available_View (Typ_1) = Available_View (Typ_2)
7574 elsif From_Limited_With (Typ_1) then
7575 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7577 elsif From_Limited_With (Typ_2) then
7578 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7583 end Matches_Limited_With_View;
7587 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7589 Type_1 : Entity_Id := T1;
7590 Type_2 : Entity_Id := T2;
7592 -- Start of processing for Conforming_Types
7595 -- The context is an instance association for a formal access-to-
7596 -- subprogram type; the formal parameter types require mapping because
7597 -- they may denote other formal parameters of the generic unit.
7600 Type_1 := Get_Instance_Of (T1);
7601 Type_2 := Get_Instance_Of (T2);
7604 -- If one of the types is a view of the other introduced by a limited
7605 -- with clause, treat these as conforming for all purposes.
7607 if Matches_Limited_With_View (T1, T2) then
7610 elsif Base_Types_Match (Type_1, Type_2) then
7611 if Ctype <= Mode_Conformant then
7616 Subtypes_Statically_Match (Type_1, Type_2)
7617 and then Dimensions_Match (Type_1, Type_2);
7620 elsif Is_Incomplete_Or_Private_Type (Type_1)
7621 and then Present (Full_View (Type_1))
7622 and then Base_Types_Match (Full_View (Type_1), Type_2)
7625 Ctype <= Mode_Conformant
7626 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7628 elsif Ekind (Type_2) = E_Incomplete_Type
7629 and then Present (Full_View (Type_2))
7630 and then Base_Types_Match (Type_1, Full_View (Type_2))
7633 Ctype <= Mode_Conformant
7634 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7636 elsif Is_Private_Type (Type_2)
7637 and then In_Instance
7638 and then Present (Full_View (Type_2))
7639 and then Base_Types_Match (Type_1, Full_View (Type_2))
7642 Ctype <= Mode_Conformant
7643 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7645 -- Another confusion between views in a nested instance with an
7646 -- actual private type whose full view is not in scope.
7648 elsif Ekind (Type_2) = E_Private_Subtype
7649 and then In_Instance
7650 and then Etype (Type_2) = Type_1
7654 -- In Ada 2012, incomplete types (including limited views) can appear
7655 -- as actuals in instantiations, where they are conformant to the
7656 -- corresponding incomplete formal.
7658 elsif Is_Incomplete_Type (Type_1)
7659 and then Is_Incomplete_Type (Type_2)
7660 and then In_Instance
7661 and then (Used_As_Generic_Actual (Type_1)
7662 or else Used_As_Generic_Actual (Type_2))
7667 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7668 -- treated recursively because they carry a signature. As far as
7669 -- conformance is concerned, convention plays no role, and either
7670 -- or both could be access to protected subprograms.
7672 Are_Anonymous_Access_To_Subprogram_Types :=
7673 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7674 E_Anonymous_Access_Protected_Subprogram_Type)
7676 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7677 E_Anonymous_Access_Protected_Subprogram_Type);
7679 -- Test anonymous access type case. For this case, static subtype
7680 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7681 -- the base types because we may have built internal subtype entities
7682 -- to handle null-excluding types (see Process_Formals).
7684 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7686 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7688 -- Ada 2005 (AI-254)
7690 or else Are_Anonymous_Access_To_Subprogram_Types
7693 Desig_1 : Entity_Id;
7694 Desig_2 : Entity_Id;
7697 -- In Ada 2005, access constant indicators must match for
7698 -- subtype conformance.
7700 if Ada_Version >= Ada_2005
7701 and then Ctype >= Subtype_Conformant
7703 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7708 Desig_1 := Find_Designated_Type (Type_1);
7709 Desig_2 := Find_Designated_Type (Type_2);
7711 -- If the context is an instance association for a formal
7712 -- access-to-subprogram type; formal access parameter designated
7713 -- types require mapping because they may denote other formal
7714 -- parameters of the generic unit.
7717 Desig_1 := Get_Instance_Of (Desig_1);
7718 Desig_2 := Get_Instance_Of (Desig_2);
7721 -- It is possible for a Class_Wide_Type to be introduced for an
7722 -- incomplete type, in which case there is a separate class_ wide
7723 -- type for the full view. The types conform if their Etypes
7724 -- conform, i.e. one may be the full view of the other. This can
7725 -- only happen in the context of an access parameter, other uses
7726 -- of an incomplete Class_Wide_Type are illegal.
7728 if Is_Class_Wide_Type (Desig_1)
7730 Is_Class_Wide_Type (Desig_2)
7734 (Etype (Base_Type (Desig_1)),
7735 Etype (Base_Type (Desig_2)), Ctype);
7737 elsif Are_Anonymous_Access_To_Subprogram_Types then
7738 if Ada_Version < Ada_2005 then
7740 Ctype = Type_Conformant
7741 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7743 -- We must check the conformance of the signatures themselves
7747 Conformant : Boolean;
7750 (Desig_1, Desig_2, Ctype, False, Conformant);
7755 -- A limited view of an actual matches the corresponding
7756 -- incomplete formal.
7758 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7759 and then From_Limited_With (Desig_2)
7760 and then Used_As_Generic_Actual (Etype (Desig_2))
7765 return Base_Type (Desig_1) = Base_Type (Desig_2)
7766 and then (Ctype = Type_Conformant
7768 Subtypes_Statically_Match (Desig_1, Desig_2));
7772 -- Otherwise definitely no match
7775 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7776 and then Is_Access_Type (Type_2))
7777 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7778 and then Is_Access_Type (Type_1)))
7781 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7783 May_Hide_Profile := True;
7788 end Conforming_Types;
7790 --------------------------
7791 -- Create_Extra_Formals --
7792 --------------------------
7794 procedure Create_Extra_Formals (E : Entity_Id) is
7795 First_Extra : Entity_Id := Empty;
7797 Last_Extra : Entity_Id := Empty;
7799 function Add_Extra_Formal
7800 (Assoc_Entity : Entity_Id;
7803 Suffix : String) return Entity_Id;
7804 -- Add an extra formal to the current list of formals and extra formals.
7805 -- The extra formal is added to the end of the list of extra formals,
7806 -- and also returned as the result. These formals are always of mode IN.
7807 -- The new formal has the type Typ, is declared in Scope, and its name
7808 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7809 -- The following suffixes are currently used. They should not be changed
7810 -- without coordinating with CodePeer, which makes use of these to
7811 -- provide better messages.
7813 -- O denotes the Constrained bit.
7814 -- L denotes the accessibility level.
7815 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7816 -- the full list in exp_ch6.BIP_Formal_Kind.
7818 ----------------------
7819 -- Add_Extra_Formal --
7820 ----------------------
7822 function Add_Extra_Formal
7823 (Assoc_Entity : Entity_Id;
7826 Suffix : String) return Entity_Id
7828 EF : constant Entity_Id :=
7829 Make_Defining_Identifier (Sloc (Assoc_Entity),
7830 Chars => New_External_Name (Chars (Assoc_Entity),
7834 -- A little optimization. Never generate an extra formal for the
7835 -- _init operand of an initialization procedure, since it could
7838 if Chars (Formal) = Name_uInit then
7842 Set_Ekind (EF, E_In_Parameter);
7843 Set_Actual_Subtype (EF, Typ);
7844 Set_Etype (EF, Typ);
7845 Set_Scope (EF, Scope);
7846 Set_Mechanism (EF, Default_Mechanism);
7847 Set_Formal_Validity (EF);
7849 if No (First_Extra) then
7851 Set_Extra_Formals (Scope, EF);
7854 if Present (Last_Extra) then
7855 Set_Extra_Formal (Last_Extra, EF);
7861 end Add_Extra_Formal;
7865 Formal_Type : Entity_Id;
7866 P_Formal : Entity_Id := Empty;
7868 -- Start of processing for Create_Extra_Formals
7871 -- We never generate extra formals if expansion is not active because we
7872 -- don't need them unless we are generating code.
7874 if not Expander_Active then
7878 -- No need to generate extra formals in interface thunks whose target
7879 -- primitive has no extra formals.
7881 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7885 -- If this is a derived subprogram then the subtypes of the parent
7886 -- subprogram's formal parameters will be used to determine the need
7887 -- for extra formals.
7889 if Is_Overloadable (E) and then Present (Alias (E)) then
7890 P_Formal := First_Formal (Alias (E));
7893 Formal := First_Formal (E);
7894 while Present (Formal) loop
7895 Last_Extra := Formal;
7896 Next_Formal (Formal);
7899 -- If Extra_Formals were already created, don't do it again. This
7900 -- situation may arise for subprogram types created as part of
7901 -- dispatching calls (see Expand_Dispatching_Call).
7903 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7907 -- If the subprogram is a predefined dispatching subprogram then don't
7908 -- generate any extra constrained or accessibility level formals. In
7909 -- general we suppress these for internal subprograms (by not calling
7910 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7911 -- generated stream attributes do get passed through because extra
7912 -- build-in-place formals are needed in some cases (limited 'Input).
7914 if Is_Predefined_Internal_Operation (E) then
7915 goto Test_For_Func_Result_Extras;
7918 Formal := First_Formal (E);
7919 while Present (Formal) loop
7921 -- Create extra formal for supporting the attribute 'Constrained.
7922 -- The case of a private type view without discriminants also
7923 -- requires the extra formal if the underlying type has defaulted
7926 if Ekind (Formal) /= E_In_Parameter then
7927 if Present (P_Formal) then
7928 Formal_Type := Etype (P_Formal);
7930 Formal_Type := Etype (Formal);
7933 -- Do not produce extra formals for Unchecked_Union parameters.
7934 -- Jump directly to the end of the loop.
7936 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7937 goto Skip_Extra_Formal_Generation;
7940 if not Has_Discriminants (Formal_Type)
7941 and then Ekind (Formal_Type) in Private_Kind
7942 and then Present (Underlying_Type (Formal_Type))
7944 Formal_Type := Underlying_Type (Formal_Type);
7947 -- Suppress the extra formal if formal's subtype is constrained or
7948 -- indefinite, or we're compiling for Ada 2012 and the underlying
7949 -- type is tagged and limited. In Ada 2012, a limited tagged type
7950 -- can have defaulted discriminants, but 'Constrained is required
7951 -- to return True, so the formal is never needed (see AI05-0214).
7952 -- Note that this ensures consistency of calling sequences for
7953 -- dispatching operations when some types in a class have defaults
7954 -- on discriminants and others do not (and requiring the extra
7955 -- formal would introduce distributed overhead).
7957 -- If the type does not have a completion yet, treat as prior to
7958 -- Ada 2012 for consistency.
7960 if Has_Discriminants (Formal_Type)
7961 and then not Is_Constrained (Formal_Type)
7962 and then Is_Definite_Subtype (Formal_Type)
7963 and then (Ada_Version < Ada_2012
7964 or else No (Underlying_Type (Formal_Type))
7966 (Is_Limited_Type (Formal_Type)
7969 (Underlying_Type (Formal_Type)))))
7971 Set_Extra_Constrained
7972 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7976 -- Create extra formal for supporting accessibility checking. This
7977 -- is done for both anonymous access formals and formals of named
7978 -- access types that are marked as controlling formals. The latter
7979 -- case can occur when Expand_Dispatching_Call creates a subprogram
7980 -- type and substitutes the types of access-to-class-wide actuals
7981 -- for the anonymous access-to-specific-type of controlling formals.
7982 -- Base_Type is applied because in cases where there is a null
7983 -- exclusion the formal may have an access subtype.
7985 -- This is suppressed if we specifically suppress accessibility
7986 -- checks at the package level for either the subprogram, or the
7987 -- package in which it resides. However, we do not suppress it
7988 -- simply if the scope has accessibility checks suppressed, since
7989 -- this could cause trouble when clients are compiled with a
7990 -- different suppression setting. The explicit checks at the
7991 -- package level are safe from this point of view.
7993 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7994 or else (Is_Controlling_Formal (Formal)
7995 and then Is_Access_Type (Base_Type (Etype (Formal)))))
7997 (Explicit_Suppress (E, Accessibility_Check)
7999 Explicit_Suppress (Scope (E), Accessibility_Check))
8002 or else Present (Extra_Accessibility (P_Formal)))
8004 Set_Extra_Accessibility
8005 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8008 -- This label is required when skipping extra formal generation for
8009 -- Unchecked_Union parameters.
8011 <<Skip_Extra_Formal_Generation>>
8013 if Present (P_Formal) then
8014 Next_Formal (P_Formal);
8017 Next_Formal (Formal);
8020 <<Test_For_Func_Result_Extras>>
8022 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8023 -- function call is ... determined by the point of call ...".
8025 if Needs_Result_Accessibility_Level (E) then
8026 Set_Extra_Accessibility_Of_Result
8027 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8030 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8031 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8033 if Is_Build_In_Place_Function (E) then
8035 Result_Subt : constant Entity_Id := Etype (E);
8036 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8037 Formal_Typ : Entity_Id;
8038 Subp_Decl : Node_Id;
8039 Discard : Entity_Id;
8042 -- In the case of functions with unconstrained result subtypes,
8043 -- add a 4-state formal indicating whether the return object is
8044 -- allocated by the caller (1), or should be allocated by the
8045 -- callee on the secondary stack (2), in the global heap (3), or
8046 -- in a user-defined storage pool (4). For the moment we just use
8047 -- Natural for the type of this formal. Note that this formal
8048 -- isn't usually needed in the case where the result subtype is
8049 -- constrained, but it is needed when the function has a tagged
8050 -- result, because generally such functions can be called in a
8051 -- dispatching context and such calls must be handled like calls
8052 -- to a class-wide function.
8054 if Needs_BIP_Alloc_Form (E) then
8057 (E, Standard_Natural,
8058 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8060 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8061 -- use a user-defined pool. This formal is not added on
8062 -- ZFP as those targets do not support pools.
8064 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8067 (E, RTE (RE_Root_Storage_Pool_Ptr),
8068 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8072 -- In the case of functions whose result type needs finalization,
8073 -- add an extra formal which represents the finalization master.
8075 if Needs_BIP_Finalization_Master (E) then
8078 (E, RTE (RE_Finalization_Master_Ptr),
8079 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8082 -- When the result type contains tasks, add two extra formals: the
8083 -- master of the tasks to be created, and the caller's activation
8086 if Has_Task (Full_Subt) then
8089 (E, RTE (RE_Master_Id),
8090 E, BIP_Formal_Suffix (BIP_Task_Master));
8093 (E, RTE (RE_Activation_Chain_Access),
8094 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8097 -- All build-in-place functions get an extra formal that will be
8098 -- passed the address of the return object within the caller.
8101 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8103 -- Incomplete_View_From_Limited_With is needed here because
8104 -- gigi gets confused if the designated type is the full view
8105 -- coming from a limited-with'ed package. In the normal case,
8106 -- (no limited with) Incomplete_View_From_Limited_With
8107 -- returns Result_Subt.
8109 Set_Directly_Designated_Type
8110 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8111 Set_Etype (Formal_Typ, Formal_Typ);
8112 Set_Depends_On_Private
8113 (Formal_Typ, Has_Private_Component (Formal_Typ));
8114 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8115 Set_Is_Access_Constant (Formal_Typ, False);
8117 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8118 -- the designated type comes from the limited view (for back-end
8121 Set_From_Limited_With
8122 (Formal_Typ, From_Limited_With (Result_Subt));
8124 Layout_Type (Formal_Typ);
8126 -- Force the definition of the Itype in case of internal function
8127 -- calls within the same or nested scope.
8129 if Is_Subprogram_Or_Generic_Subprogram (E) then
8130 Subp_Decl := Parent (E);
8132 -- The insertion point for an Itype reference should be after
8133 -- the unit declaration node of the subprogram. An exception
8134 -- to this are inherited operations from a parent type in which
8135 -- case the derived type acts as their parent.
8137 if Nkind_In (Subp_Decl, N_Function_Specification,
8138 N_Procedure_Specification)
8140 Subp_Decl := Parent (Subp_Decl);
8143 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8148 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8152 -- If this is an instance of a generic, we need to have extra formals
8155 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8156 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8158 end Create_Extra_Formals;
8160 -----------------------------
8161 -- Enter_Overloaded_Entity --
8162 -----------------------------
8164 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8165 function Matches_Predefined_Op return Boolean;
8166 -- This returns an approximation of whether S matches a predefined
8167 -- operator, based on the operator symbol, and the parameter and result
8168 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8170 ---------------------------
8171 -- Matches_Predefined_Op --
8172 ---------------------------
8174 function Matches_Predefined_Op return Boolean is
8175 Formal_1 : constant Entity_Id := First_Formal (S);
8176 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8177 Op : constant Name_Id := Chars (S);
8178 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8179 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8184 if Present (Formal_2) then
8186 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8189 -- All but "&" and "**" have same-types parameters
8198 if Type_1 /= Type_2 then
8203 -- Check parameter and result types
8211 Is_Boolean_Type (Result_Type)
8212 and then Result_Type = Type_1;
8218 Is_Integer_Type (Result_Type)
8219 and then Result_Type = Type_1;
8227 Is_Numeric_Type (Result_Type)
8228 and then Result_Type = Type_1;
8234 Is_Boolean_Type (Result_Type)
8235 and then not Is_Limited_Type (Type_1);
8243 Is_Boolean_Type (Result_Type)
8244 and then (Is_Array_Type (Type_1)
8245 or else Is_Scalar_Type (Type_1));
8247 when Name_Op_Concat =>
8248 return Is_Array_Type (Result_Type);
8250 when Name_Op_Expon =>
8252 (Is_Integer_Type (Result_Type)
8253 or else Is_Floating_Point_Type (Result_Type))
8254 and then Result_Type = Type_1
8255 and then Type_2 = Standard_Integer;
8258 raise Program_Error;
8271 Is_Numeric_Type (Result_Type)
8272 and then Result_Type = Type_1;
8276 Is_Boolean_Type (Result_Type)
8277 and then Result_Type = Type_1;
8280 raise Program_Error;
8283 end Matches_Predefined_Op;
8287 E : Entity_Id := Current_Entity_In_Scope (S);
8288 C_E : Entity_Id := Current_Entity (S);
8290 -- Start of processing for Enter_Overloaded_Entity
8294 Set_Has_Homonym (E);
8295 Set_Has_Homonym (S);
8298 Set_Is_Immediately_Visible (S);
8299 Set_Scope (S, Current_Scope);
8301 -- Chain new entity if front of homonym in current scope, so that
8302 -- homonyms are contiguous.
8304 if Present (E) and then E /= C_E then
8305 while Homonym (C_E) /= E loop
8306 C_E := Homonym (C_E);
8309 Set_Homonym (C_E, S);
8313 Set_Current_Entity (S);
8318 if Is_Inherited_Operation (S) then
8319 Append_Inherited_Subprogram (S);
8321 Append_Entity (S, Current_Scope);
8324 Set_Public_Status (S);
8326 if Debug_Flag_E then
8327 Write_Str ("New overloaded entity chain: ");
8328 Write_Name (Chars (S));
8331 while Present (E) loop
8332 Write_Str (" "); Write_Int (Int (E));
8339 -- Generate warning for hiding
8342 and then Comes_From_Source (S)
8343 and then In_Extended_Main_Source_Unit (S)
8350 -- Warn unless genuine overloading. Do not emit warning on
8351 -- hiding predefined operators in Standard (these are either an
8352 -- (artifact of our implicit declarations, or simple noise) but
8353 -- keep warning on a operator defined on a local subtype, because
8354 -- of the real danger that different operators may be applied in
8355 -- various parts of the program.
8357 -- Note that if E and S have the same scope, there is never any
8358 -- hiding. Either the two conflict, and the program is illegal,
8359 -- or S is overriding an implicit inherited subprogram.
8361 if Scope (E) /= Scope (S)
8362 and then (not Is_Overloadable (E)
8363 or else Subtype_Conformant (E, S))
8364 and then (Is_Immediately_Visible (E)
8365 or else Is_Potentially_Use_Visible (S))
8367 if Scope (E) = Standard_Standard then
8368 if Nkind (S) = N_Defining_Operator_Symbol
8369 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8371 and then Matches_Predefined_Op
8374 ("declaration of & hides predefined operator?h?", S);
8377 -- E not immediately within Standard
8380 Error_Msg_Sloc := Sloc (E);
8381 Error_Msg_N ("declaration of & hides one #?h?", S);
8386 end Enter_Overloaded_Entity;
8388 -----------------------------
8389 -- Check_Untagged_Equality --
8390 -----------------------------
8392 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8393 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8394 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8398 -- This check applies only if we have a subprogram declaration with an
8399 -- untagged record type.
8401 if Nkind (Decl) /= N_Subprogram_Declaration
8402 or else not Is_Record_Type (Typ)
8403 or else Is_Tagged_Type (Typ)
8408 -- In Ada 2012 case, we will output errors or warnings depending on
8409 -- the setting of debug flag -gnatd.E.
8411 if Ada_Version >= Ada_2012 then
8412 Error_Msg_Warn := Debug_Flag_Dot_EE;
8414 -- In earlier versions of Ada, nothing to do unless we are warning on
8415 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8418 if not Warn_On_Ada_2012_Compatibility then
8423 -- Cases where the type has already been frozen
8425 if Is_Frozen (Typ) then
8427 -- The check applies to a primitive operation, so check that type
8428 -- and equality operation are in the same scope.
8430 if Scope (Typ) /= Current_Scope then
8433 -- If the type is a generic actual (sub)type, the operation is not
8434 -- primitive either because the base type is declared elsewhere.
8436 elsif Is_Generic_Actual_Type (Typ) then
8439 -- Here we have a definite error of declaration after freezing
8442 if Ada_Version >= Ada_2012 then
8444 ("equality operator must be declared before type & is "
8445 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8447 -- In Ada 2012 mode with error turned to warning, output one
8448 -- more warning to warn that the equality operation may not
8449 -- compose. This is the consequence of ignoring the error.
8451 if Error_Msg_Warn then
8452 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8457 ("equality operator must be declared before type& is "
8458 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8461 -- If we are in the package body, we could just move the
8462 -- declaration to the package spec, so add a message saying that.
8464 if In_Package_Body (Scope (Typ)) then
8465 if Ada_Version >= Ada_2012 then
8467 ("\move declaration to package spec<<", Eq_Op);
8470 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8473 -- Otherwise try to find the freezing point for better message.
8476 Obj_Decl := Next (Parent (Typ));
8477 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8478 if Nkind (Obj_Decl) = N_Object_Declaration
8479 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8481 -- Freezing point, output warnings
8483 if Ada_Version >= Ada_2012 then
8485 ("type& is frozen by declaration??", Obj_Decl, Typ);
8487 ("\an equality operator cannot be declared after "
8492 ("type& is frozen by declaration (Ada 2012)?y?",
8495 ("\an equality operator cannot be declared after "
8496 & "this point (Ada 2012)?y?",
8502 -- If we reach generated code for subprogram declaration
8503 -- or body, it is the body that froze the type and the
8504 -- declaration is legal.
8506 elsif Sloc (Obj_Decl) = Sloc (Decl) then
8515 -- Here if type is not frozen yet. It is illegal to have a primitive
8516 -- equality declared in the private part if the type is visible.
8518 elsif not In_Same_List (Parent (Typ), Decl)
8519 and then not Is_Limited_Type (Typ)
8521 -- Shouldn't we give an RM reference here???
8523 if Ada_Version >= Ada_2012 then
8525 ("equality operator appears too late<<", Eq_Op);
8528 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8531 -- No error detected
8536 end Check_Untagged_Equality;
8538 -----------------------------
8539 -- Find_Corresponding_Spec --
8540 -----------------------------
8542 function Find_Corresponding_Spec
8544 Post_Error : Boolean := True) return Entity_Id
8546 Spec : constant Node_Id := Specification (N);
8547 Designator : constant Entity_Id := Defining_Entity (Spec);
8551 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8552 -- Even if fully conformant, a body may depend on a generic actual when
8553 -- the spec does not, or vice versa, in which case they were distinct
8554 -- entities in the generic.
8556 -------------------------------
8557 -- Different_Generic_Profile --
8558 -------------------------------
8560 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8563 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8564 -- Check that the types of corresponding formals have the same
8565 -- generic actual if any. We have to account for subtypes of a
8566 -- generic formal, declared between a spec and a body, which may
8567 -- appear distinct in an instance but matched in the generic, and
8568 -- the subtype may be used either in the spec or the body of the
8569 -- subprogram being checked.
8571 -------------------------
8572 -- Same_Generic_Actual --
8573 -------------------------
8575 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8577 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8578 -- Predicate to check whether S1 is a subtype of S2 in the source
8581 -------------------------
8582 -- Is_Declared_Subtype --
8583 -------------------------
8585 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8587 return Comes_From_Source (Parent (S1))
8588 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8589 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8590 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8591 end Is_Declared_Subtype;
8593 -- Start of processing for Same_Generic_Actual
8596 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8597 or else Is_Declared_Subtype (T1, T2)
8598 or else Is_Declared_Subtype (T2, T1);
8599 end Same_Generic_Actual;
8601 -- Start of processing for Different_Generic_Profile
8604 if not In_Instance then
8607 elsif Ekind (E) = E_Function
8608 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8613 F1 := First_Formal (Designator);
8614 F2 := First_Formal (E);
8615 while Present (F1) loop
8616 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8625 end Different_Generic_Profile;
8627 -- Start of processing for Find_Corresponding_Spec
8630 E := Current_Entity (Designator);
8631 while Present (E) loop
8633 -- We are looking for a matching spec. It must have the same scope,
8634 -- and the same name, and either be type conformant, or be the case
8635 -- of a library procedure spec and its body (which belong to one
8636 -- another regardless of whether they are type conformant or not).
8638 if Scope (E) = Current_Scope then
8639 if Current_Scope = Standard_Standard
8640 or else (Ekind (E) = Ekind (Designator)
8641 and then Type_Conformant (E, Designator))
8643 -- Within an instantiation, we know that spec and body are
8644 -- subtype conformant, because they were subtype conformant in
8645 -- the generic. We choose the subtype-conformant entity here as
8646 -- well, to resolve spurious ambiguities in the instance that
8647 -- were not present in the generic (i.e. when two different
8648 -- types are given the same actual). If we are looking for a
8649 -- spec to match a body, full conformance is expected.
8653 -- Inherit the convention and "ghostness" of the matching
8654 -- spec to ensure proper full and subtype conformance.
8656 Set_Convention (Designator, Convention (E));
8658 -- Skip past subprogram bodies and subprogram renamings that
8659 -- may appear to have a matching spec, but that aren't fully
8660 -- conformant with it. That can occur in cases where an
8661 -- actual type causes unrelated homographs in the instance.
8663 if Nkind_In (N, N_Subprogram_Body,
8664 N_Subprogram_Renaming_Declaration)
8665 and then Present (Homonym (E))
8666 and then not Fully_Conformant (Designator, E)
8670 elsif not Subtype_Conformant (Designator, E) then
8673 elsif Different_Generic_Profile (E) then
8678 -- Ada 2012 (AI05-0165): For internally generated bodies of
8679 -- null procedures locate the internally generated spec. We
8680 -- enforce mode conformance since a tagged type may inherit
8681 -- from interfaces several null primitives which differ only
8682 -- in the mode of the formals.
8684 if not (Comes_From_Source (E))
8685 and then Is_Null_Procedure (E)
8686 and then not Mode_Conformant (Designator, E)
8690 -- For null procedures coming from source that are completions,
8691 -- analysis of the generated body will establish the link.
8693 elsif Comes_From_Source (E)
8694 and then Nkind (Spec) = N_Procedure_Specification
8695 and then Null_Present (Spec)
8699 -- Expression functions can be completions, but cannot be
8700 -- completed by an explicit body.
8702 elsif Comes_From_Source (E)
8703 and then Comes_From_Source (N)
8704 and then Nkind (N) = N_Subprogram_Body
8705 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8706 N_Expression_Function
8708 Error_Msg_Sloc := Sloc (E);
8709 Error_Msg_N ("body conflicts with expression function#", N);
8712 elsif not Has_Completion (E) then
8713 if Nkind (N) /= N_Subprogram_Body_Stub then
8714 Set_Corresponding_Spec (N, E);
8717 Set_Has_Completion (E);
8720 elsif Nkind (Parent (N)) = N_Subunit then
8722 -- If this is the proper body of a subunit, the completion
8723 -- flag is set when analyzing the stub.
8727 -- If E is an internal function with a controlling result that
8728 -- was created for an operation inherited by a null extension,
8729 -- it may be overridden by a body without a previous spec (one
8730 -- more reason why these should be shunned). In that case we
8731 -- remove the generated body if present, because the current
8732 -- one is the explicit overriding.
8734 elsif Ekind (E) = E_Function
8735 and then Ada_Version >= Ada_2005
8736 and then not Comes_From_Source (E)
8737 and then Has_Controlling_Result (E)
8738 and then Is_Null_Extension (Etype (E))
8739 and then Comes_From_Source (Spec)
8741 Set_Has_Completion (E, False);
8744 and then Nkind (Parent (E)) = N_Function_Specification
8747 (Unit_Declaration_Node
8748 (Corresponding_Body (Unit_Declaration_Node (E))));
8752 -- If expansion is disabled, or if the wrapper function has
8753 -- not been generated yet, this a late body overriding an
8754 -- inherited operation, or it is an overriding by some other
8755 -- declaration before the controlling result is frozen. In
8756 -- either case this is a declaration of a new entity.
8762 -- If the body already exists, then this is an error unless
8763 -- the previous declaration is the implicit declaration of a
8764 -- derived subprogram. It is also legal for an instance to
8765 -- contain type conformant overloadable declarations (but the
8766 -- generic declaration may not), per 8.3(26/2).
8768 elsif No (Alias (E))
8769 and then not Is_Intrinsic_Subprogram (E)
8770 and then not In_Instance
8773 Error_Msg_Sloc := Sloc (E);
8775 if Is_Imported (E) then
8777 ("body not allowed for imported subprogram & declared#",
8780 Error_Msg_NE ("duplicate body for & declared#", N, E);
8784 -- Child units cannot be overloaded, so a conformance mismatch
8785 -- between body and a previous spec is an error.
8787 elsif Is_Child_Unit (E)
8789 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8791 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8796 ("body of child unit does not match previous declaration", N);
8804 -- On exit, we know that no previous declaration of subprogram exists
8807 end Find_Corresponding_Spec;
8809 ----------------------
8810 -- Fully_Conformant --
8811 ----------------------
8813 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8816 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8818 end Fully_Conformant;
8820 ----------------------------------
8821 -- Fully_Conformant_Expressions --
8822 ----------------------------------
8824 function Fully_Conformant_Expressions
8825 (Given_E1 : Node_Id;
8826 Given_E2 : Node_Id) return Boolean
8828 E1 : constant Node_Id := Original_Node (Given_E1);
8829 E2 : constant Node_Id := Original_Node (Given_E2);
8830 -- We always test conformance on original nodes, since it is possible
8831 -- for analysis and/or expansion to make things look as though they
8832 -- conform when they do not, e.g. by converting 1+2 into 3.
8834 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8835 renames Fully_Conformant_Expressions;
8837 function FCL (L1, L2 : List_Id) return Boolean;
8838 -- Compare elements of two lists for conformance. Elements have to be
8839 -- conformant, and actuals inserted as default parameters do not match
8840 -- explicit actuals with the same value.
8842 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8843 -- Compare an operator node with a function call
8849 function FCL (L1, L2 : List_Id) return Boolean is
8853 if L1 = No_List then
8859 if L2 = No_List then
8865 -- Compare two lists, skipping rewrite insertions (we want to compare
8866 -- the original trees, not the expanded versions).
8869 if Is_Rewrite_Insertion (N1) then
8871 elsif Is_Rewrite_Insertion (N2) then
8877 elsif not FCE (N1, N2) then
8890 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8891 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8896 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8901 Act := First (Actuals);
8903 if Nkind (Op_Node) in N_Binary_Op then
8904 if not FCE (Left_Opnd (Op_Node), Act) then
8911 return Present (Act)
8912 and then FCE (Right_Opnd (Op_Node), Act)
8913 and then No (Next (Act));
8917 -- Start of processing for Fully_Conformant_Expressions
8920 -- Nonconformant if paren count does not match. Note: if some idiot
8921 -- complains that we don't do this right for more than 3 levels of
8922 -- parentheses, they will be treated with the respect they deserve.
8924 if Paren_Count (E1) /= Paren_Count (E2) then
8927 -- If same entities are referenced, then they are conformant even if
8928 -- they have different forms (RM 8.3.1(19-20)).
8930 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8931 if Present (Entity (E1)) then
8932 return Entity (E1) = Entity (E2)
8934 -- One may be a discriminant that has been replaced by the
8935 -- corresponding discriminal.
8938 (Chars (Entity (E1)) = Chars (Entity (E2))
8939 and then Ekind (Entity (E1)) = E_Discriminant
8940 and then Ekind (Entity (E2)) = E_In_Parameter)
8942 -- The discriminant of a protected type is transformed into
8943 -- a local constant and then into a parameter of a protected
8947 (Ekind (Entity (E1)) = E_Constant
8948 and then Ekind (Entity (E2)) = E_In_Parameter
8949 and then Present (Discriminal_Link (Entity (E1)))
8950 and then Discriminal_Link (Entity (E1)) =
8951 Discriminal_Link (Entity (E2)))
8953 -- AI12-050: The loop variables of quantified expressions match
8954 -- if they have the same identifier, even though they may have
8955 -- different entities.
8958 (Chars (Entity (E1)) = Chars (Entity (E2))
8959 and then Ekind (Entity (E1)) = E_Loop_Parameter
8960 and then Ekind (Entity (E2)) = E_Loop_Parameter)
8962 -- A call to an instantiation of Unchecked_Conversion is
8963 -- rewritten with the name of the generated function created for
8964 -- the instance, and this must be special-cased.
8967 (Ekind (Entity (E1)) = E_Function
8968 and then Is_Intrinsic_Subprogram (Entity (E1))
8969 and then Is_Generic_Instance (Entity (E1))
8970 and then Entity (E2) = Alias (Entity (E1)));
8972 elsif Nkind (E1) = N_Expanded_Name
8973 and then Nkind (E2) = N_Expanded_Name
8974 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8975 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8977 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8980 -- Identifiers in component associations don't always have
8981 -- entities, but their names must conform.
8983 return Nkind (E1) = N_Identifier
8984 and then Nkind (E2) = N_Identifier
8985 and then Chars (E1) = Chars (E2);
8988 elsif Nkind (E1) = N_Character_Literal
8989 and then Nkind (E2) = N_Expanded_Name
8991 return Nkind (Selector_Name (E2)) = N_Character_Literal
8992 and then Chars (E1) = Chars (Selector_Name (E2));
8994 elsif Nkind (E2) = N_Character_Literal
8995 and then Nkind (E1) = N_Expanded_Name
8997 return Nkind (Selector_Name (E1)) = N_Character_Literal
8998 and then Chars (E2) = Chars (Selector_Name (E1));
9000 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9001 return FCO (E1, E2);
9003 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9004 return FCO (E2, E1);
9006 -- Otherwise we must have the same syntactic entity
9008 elsif Nkind (E1) /= Nkind (E2) then
9011 -- At this point, we specialize by node type
9017 FCL (Expressions (E1), Expressions (E2))
9019 FCL (Component_Associations (E1),
9020 Component_Associations (E2));
9023 if Nkind (Expression (E1)) = N_Qualified_Expression
9025 Nkind (Expression (E2)) = N_Qualified_Expression
9027 return FCE (Expression (E1), Expression (E2));
9029 -- Check that the subtype marks and any constraints
9034 Indic1 : constant Node_Id := Expression (E1);
9035 Indic2 : constant Node_Id := Expression (E2);
9040 if Nkind (Indic1) /= N_Subtype_Indication then
9042 Nkind (Indic2) /= N_Subtype_Indication
9043 and then Entity (Indic1) = Entity (Indic2);
9045 elsif Nkind (Indic2) /= N_Subtype_Indication then
9047 Nkind (Indic1) /= N_Subtype_Indication
9048 and then Entity (Indic1) = Entity (Indic2);
9051 if Entity (Subtype_Mark (Indic1)) /=
9052 Entity (Subtype_Mark (Indic2))
9057 Elt1 := First (Constraints (Constraint (Indic1)));
9058 Elt2 := First (Constraints (Constraint (Indic2)));
9059 while Present (Elt1) and then Present (Elt2) loop
9060 if not FCE (Elt1, Elt2) then
9073 when N_Attribute_Reference =>
9075 Attribute_Name (E1) = Attribute_Name (E2)
9076 and then FCL (Expressions (E1), Expressions (E2));
9080 Entity (E1) = Entity (E2)
9081 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9082 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9084 when N_Membership_Test
9088 FCE (Left_Opnd (E1), Left_Opnd (E2))
9090 FCE (Right_Opnd (E1), Right_Opnd (E2));
9092 when N_Case_Expression =>
9098 if not FCE (Expression (E1), Expression (E2)) then
9102 Alt1 := First (Alternatives (E1));
9103 Alt2 := First (Alternatives (E2));
9105 if Present (Alt1) /= Present (Alt2) then
9107 elsif No (Alt1) then
9111 if not FCE (Expression (Alt1), Expression (Alt2))
9112 or else not FCL (Discrete_Choices (Alt1),
9113 Discrete_Choices (Alt2))
9124 when N_Character_Literal =>
9126 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9128 when N_Component_Association =>
9130 FCL (Choices (E1), Choices (E2))
9132 FCE (Expression (E1), Expression (E2));
9134 when N_Explicit_Dereference =>
9136 FCE (Prefix (E1), Prefix (E2));
9138 when N_Extension_Aggregate =>
9140 FCL (Expressions (E1), Expressions (E2))
9141 and then Null_Record_Present (E1) =
9142 Null_Record_Present (E2)
9143 and then FCL (Component_Associations (E1),
9144 Component_Associations (E2));
9146 when N_Function_Call =>
9148 FCE (Name (E1), Name (E2))
9150 FCL (Parameter_Associations (E1),
9151 Parameter_Associations (E2));
9153 when N_If_Expression =>
9155 FCL (Expressions (E1), Expressions (E2));
9157 when N_Indexed_Component =>
9159 FCE (Prefix (E1), Prefix (E2))
9161 FCL (Expressions (E1), Expressions (E2));
9163 when N_Integer_Literal =>
9164 return (Intval (E1) = Intval (E2));
9169 when N_Operator_Symbol =>
9171 Chars (E1) = Chars (E2);
9173 when N_Others_Choice =>
9176 when N_Parameter_Association =>
9178 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9179 and then FCE (Explicit_Actual_Parameter (E1),
9180 Explicit_Actual_Parameter (E2));
9182 when N_Qualified_Expression
9184 | N_Unchecked_Type_Conversion
9187 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9189 FCE (Expression (E1), Expression (E2));
9191 when N_Quantified_Expression =>
9192 if not FCE (Condition (E1), Condition (E2)) then
9196 if Present (Loop_Parameter_Specification (E1))
9197 and then Present (Loop_Parameter_Specification (E2))
9200 L1 : constant Node_Id :=
9201 Loop_Parameter_Specification (E1);
9202 L2 : constant Node_Id :=
9203 Loop_Parameter_Specification (E2);
9207 Reverse_Present (L1) = Reverse_Present (L2)
9209 FCE (Defining_Identifier (L1),
9210 Defining_Identifier (L2))
9212 FCE (Discrete_Subtype_Definition (L1),
9213 Discrete_Subtype_Definition (L2));
9216 elsif Present (Iterator_Specification (E1))
9217 and then Present (Iterator_Specification (E2))
9220 I1 : constant Node_Id := Iterator_Specification (E1);
9221 I2 : constant Node_Id := Iterator_Specification (E2);
9225 FCE (Defining_Identifier (I1),
9226 Defining_Identifier (I2))
9228 Of_Present (I1) = Of_Present (I2)
9230 Reverse_Present (I1) = Reverse_Present (I2)
9231 and then FCE (Name (I1), Name (I2))
9232 and then FCE (Subtype_Indication (I1),
9233 Subtype_Indication (I2));
9236 -- The quantified expressions used different specifications to
9237 -- walk their respective ranges.
9245 FCE (Low_Bound (E1), Low_Bound (E2))
9247 FCE (High_Bound (E1), High_Bound (E2));
9249 when N_Real_Literal =>
9250 return (Realval (E1) = Realval (E2));
9252 when N_Selected_Component =>
9254 FCE (Prefix (E1), Prefix (E2))
9256 FCE (Selector_Name (E1), Selector_Name (E2));
9260 FCE (Prefix (E1), Prefix (E2))
9262 FCE (Discrete_Range (E1), Discrete_Range (E2));
9264 when N_String_Literal =>
9266 S1 : constant String_Id := Strval (E1);
9267 S2 : constant String_Id := Strval (E2);
9268 L1 : constant Nat := String_Length (S1);
9269 L2 : constant Nat := String_Length (S2);
9276 for J in 1 .. L1 loop
9277 if Get_String_Char (S1, J) /=
9278 Get_String_Char (S2, J)
9290 Entity (E1) = Entity (E2)
9292 FCE (Right_Opnd (E1), Right_Opnd (E2));
9294 -- All other node types cannot appear in this context. Strictly
9295 -- we should raise a fatal internal error. Instead we just ignore
9296 -- the nodes. This means that if anyone makes a mistake in the
9297 -- expander and mucks an expression tree irretrievably, the result
9298 -- will be a failure to detect a (probably very obscure) case
9299 -- of non-conformance, which is better than bombing on some
9300 -- case where two expressions do in fact conform.
9306 end Fully_Conformant_Expressions;
9308 ----------------------------------------
9309 -- Fully_Conformant_Discrete_Subtypes --
9310 ----------------------------------------
9312 function Fully_Conformant_Discrete_Subtypes
9313 (Given_S1 : Node_Id;
9314 Given_S2 : Node_Id) return Boolean
9316 S1 : constant Node_Id := Original_Node (Given_S1);
9317 S2 : constant Node_Id := Original_Node (Given_S2);
9319 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9320 -- Special-case for a bound given by a discriminant, which in the body
9321 -- is replaced with the discriminal of the enclosing type.
9323 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9324 -- Check both bounds
9326 -----------------------
9327 -- Conforming_Bounds --
9328 -----------------------
9330 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9332 if Is_Entity_Name (B1)
9333 and then Is_Entity_Name (B2)
9334 and then Ekind (Entity (B1)) = E_Discriminant
9336 return Chars (B1) = Chars (B2);
9339 return Fully_Conformant_Expressions (B1, B2);
9341 end Conforming_Bounds;
9343 -----------------------
9344 -- Conforming_Ranges --
9345 -----------------------
9347 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9350 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9352 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9353 end Conforming_Ranges;
9355 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9358 if Nkind (S1) /= Nkind (S2) then
9361 elsif Is_Entity_Name (S1) then
9362 return Entity (S1) = Entity (S2);
9364 elsif Nkind (S1) = N_Range then
9365 return Conforming_Ranges (S1, S2);
9367 elsif Nkind (S1) = N_Subtype_Indication then
9369 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9372 (Range_Expression (Constraint (S1)),
9373 Range_Expression (Constraint (S2)));
9377 end Fully_Conformant_Discrete_Subtypes;
9379 --------------------
9380 -- Install_Entity --
9381 --------------------
9383 procedure Install_Entity (E : Entity_Id) is
9384 Prev : constant Entity_Id := Current_Entity (E);
9386 Set_Is_Immediately_Visible (E);
9387 Set_Current_Entity (E);
9388 Set_Homonym (E, Prev);
9391 ---------------------
9392 -- Install_Formals --
9393 ---------------------
9395 procedure Install_Formals (Id : Entity_Id) is
9398 F := First_Formal (Id);
9399 while Present (F) loop
9403 end Install_Formals;
9405 -----------------------------
9406 -- Is_Interface_Conformant --
9407 -----------------------------
9409 function Is_Interface_Conformant
9410 (Tagged_Type : Entity_Id;
9411 Iface_Prim : Entity_Id;
9412 Prim : Entity_Id) return Boolean
9414 -- The operation may in fact be an inherited (implicit) operation
9415 -- rather than the original interface primitive, so retrieve the
9416 -- ultimate ancestor.
9418 Iface : constant Entity_Id :=
9419 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9420 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9422 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9423 -- Return the controlling formal of Prim
9425 ------------------------
9426 -- Controlling_Formal --
9427 ------------------------
9429 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9433 E := First_Entity (Prim);
9434 while Present (E) loop
9435 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9443 end Controlling_Formal;
9447 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9448 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9450 -- Start of processing for Is_Interface_Conformant
9453 pragma Assert (Is_Subprogram (Iface_Prim)
9454 and then Is_Subprogram (Prim)
9455 and then Is_Dispatching_Operation (Iface_Prim)
9456 and then Is_Dispatching_Operation (Prim));
9458 pragma Assert (Is_Interface (Iface)
9459 or else (Present (Alias (Iface_Prim))
9462 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9464 if Prim = Iface_Prim
9465 or else not Is_Subprogram (Prim)
9466 or else Ekind (Prim) /= Ekind (Iface_Prim)
9467 or else not Is_Dispatching_Operation (Prim)
9468 or else Scope (Prim) /= Scope (Tagged_Type)
9470 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9471 or else not Primitive_Names_Match (Iface_Prim, Prim)
9475 -- The mode of the controlling formals must match
9477 elsif Present (Iface_Ctrl_F)
9478 and then Present (Prim_Ctrl_F)
9479 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9483 -- Case of a procedure, or a function whose result type matches the
9484 -- result type of the interface primitive, or a function that has no
9485 -- controlling result (I or access I).
9487 elsif Ekind (Iface_Prim) = E_Procedure
9488 or else Etype (Prim) = Etype (Iface_Prim)
9489 or else not Has_Controlling_Result (Prim)
9491 return Type_Conformant
9492 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9494 -- Case of a function returning an interface, or an access to one. Check
9495 -- that the return types correspond.
9497 elsif Implements_Interface (Typ, Iface) then
9498 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9500 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9505 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9506 Skip_Controlling_Formals => True);
9512 end Is_Interface_Conformant;
9514 ---------------------------------
9515 -- Is_Non_Overriding_Operation --
9516 ---------------------------------
9518 function Is_Non_Overriding_Operation
9519 (Prev_E : Entity_Id;
9520 New_E : Entity_Id) return Boolean
9524 G_Typ : Entity_Id := Empty;
9526 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9527 -- If F_Type is a derived type associated with a generic actual subtype,
9528 -- then return its Generic_Parent_Type attribute, else return Empty.
9530 function Types_Correspond
9531 (P_Type : Entity_Id;
9532 N_Type : Entity_Id) return Boolean;
9533 -- Returns true if and only if the types (or designated types in the
9534 -- case of anonymous access types) are the same or N_Type is derived
9535 -- directly or indirectly from P_Type.
9537 -----------------------------
9538 -- Get_Generic_Parent_Type --
9539 -----------------------------
9541 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9547 if Is_Derived_Type (F_Typ)
9548 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9550 -- The tree must be traversed to determine the parent subtype in
9551 -- the generic unit, which unfortunately isn't always available
9552 -- via semantic attributes. ??? (Note: The use of Original_Node
9553 -- is needed for cases where a full derived type has been
9556 -- If the parent type is a scalar type, the derivation creates
9557 -- an anonymous base type for it, and the source type is its
9560 if Is_Scalar_Type (F_Typ)
9561 and then not Comes_From_Source (F_Typ)
9565 (Original_Node (Parent (First_Subtype (F_Typ))));
9567 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9569 if Nkind (Defn) = N_Derived_Type_Definition then
9570 Indic := Subtype_Indication (Defn);
9572 if Nkind (Indic) = N_Subtype_Indication then
9573 G_Typ := Entity (Subtype_Mark (Indic));
9575 G_Typ := Entity (Indic);
9578 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9579 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9581 return Generic_Parent_Type (Parent (G_Typ));
9587 end Get_Generic_Parent_Type;
9589 ----------------------
9590 -- Types_Correspond --
9591 ----------------------
9593 function Types_Correspond
9594 (P_Type : Entity_Id;
9595 N_Type : Entity_Id) return Boolean
9597 Prev_Type : Entity_Id := Base_Type (P_Type);
9598 New_Type : Entity_Id := Base_Type (N_Type);
9601 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9602 Prev_Type := Designated_Type (Prev_Type);
9605 if Ekind (New_Type) = E_Anonymous_Access_Type then
9606 New_Type := Designated_Type (New_Type);
9609 if Prev_Type = New_Type then
9612 elsif not Is_Class_Wide_Type (New_Type) then
9613 while Etype (New_Type) /= New_Type loop
9614 New_Type := Etype (New_Type);
9616 if New_Type = Prev_Type then
9622 end Types_Correspond;
9624 -- Start of processing for Is_Non_Overriding_Operation
9627 -- In the case where both operations are implicit derived subprograms
9628 -- then neither overrides the other. This can only occur in certain
9629 -- obscure cases (e.g., derivation from homographs created in a generic
9632 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9635 elsif Ekind (Current_Scope) = E_Package
9636 and then Is_Generic_Instance (Current_Scope)
9637 and then In_Private_Part (Current_Scope)
9638 and then Comes_From_Source (New_E)
9640 -- We examine the formals and result type of the inherited operation,
9641 -- to determine whether their type is derived from (the instance of)
9642 -- a generic type. The first such formal or result type is the one
9645 Formal := First_Formal (Prev_E);
9647 while Present (Formal) loop
9648 F_Typ := Base_Type (Etype (Formal));
9650 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9651 F_Typ := Designated_Type (F_Typ);
9654 G_Typ := Get_Generic_Parent_Type (F_Typ);
9655 exit when Present (G_Typ);
9657 Next_Formal (Formal);
9660 -- If the function dispatches on result check the result type
9662 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9663 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9670 -- If the generic type is a private type, then the original operation
9671 -- was not overriding in the generic, because there was no primitive
9672 -- operation to override.
9674 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9675 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9676 N_Formal_Private_Type_Definition
9680 -- The generic parent type is the ancestor of a formal derived
9681 -- type declaration. We need to check whether it has a primitive
9682 -- operation that should be overridden by New_E in the generic.
9686 P_Formal : Entity_Id;
9687 N_Formal : Entity_Id;
9691 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9694 while Present (Prim_Elt) loop
9695 P_Prim := Node (Prim_Elt);
9697 if Chars (P_Prim) = Chars (New_E)
9698 and then Ekind (P_Prim) = Ekind (New_E)
9700 P_Formal := First_Formal (P_Prim);
9701 N_Formal := First_Formal (New_E);
9702 while Present (P_Formal) and then Present (N_Formal) loop
9703 P_Typ := Etype (P_Formal);
9704 N_Typ := Etype (N_Formal);
9706 if not Types_Correspond (P_Typ, N_Typ) then
9710 Next_Entity (P_Formal);
9711 Next_Entity (N_Formal);
9714 -- Found a matching primitive operation belonging to the
9715 -- formal ancestor type, so the new subprogram is
9719 and then No (N_Formal)
9720 and then (Ekind (New_E) /= E_Function
9723 (Etype (P_Prim), Etype (New_E)))
9729 Next_Elmt (Prim_Elt);
9732 -- If no match found, then the new subprogram does not override
9733 -- in the generic (nor in the instance).
9735 -- If the type in question is not abstract, and the subprogram
9736 -- is, this will be an error if the new operation is in the
9737 -- private part of the instance. Emit a warning now, which will
9738 -- make the subsequent error message easier to understand.
9740 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9741 and then Is_Abstract_Subprogram (Prev_E)
9742 and then In_Private_Part (Current_Scope)
9744 Error_Msg_Node_2 := F_Typ;
9746 ("private operation& in generic unit does not override "
9747 & "any primitive operation of& (RM 12.3 (18))??",
9757 end Is_Non_Overriding_Operation;
9759 -------------------------------------
9760 -- List_Inherited_Pre_Post_Aspects --
9761 -------------------------------------
9763 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9765 if Opt.List_Inherited_Aspects
9766 and then Is_Subprogram_Or_Generic_Subprogram (E)
9769 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9774 for Index in Subps'Range loop
9775 Items := Contract (Subps (Index));
9777 if Present (Items) then
9778 Prag := Pre_Post_Conditions (Items);
9779 while Present (Prag) loop
9780 Error_Msg_Sloc := Sloc (Prag);
9782 if Class_Present (Prag)
9783 and then not Split_PPC (Prag)
9785 if Pragma_Name (Prag) = Name_Precondition then
9787 ("info: & inherits `Pre''Class` aspect from "
9791 ("info: & inherits `Post''Class` aspect from "
9796 Prag := Next_Pragma (Prag);
9802 end List_Inherited_Pre_Post_Aspects;
9804 ------------------------------
9805 -- Make_Inequality_Operator --
9806 ------------------------------
9808 -- S is the defining identifier of an equality operator. We build a
9809 -- subprogram declaration with the right signature. This operation is
9810 -- intrinsic, because it is always expanded as the negation of the
9811 -- call to the equality function.
9813 procedure Make_Inequality_Operator (S : Entity_Id) is
9814 Loc : constant Source_Ptr := Sloc (S);
9817 Op_Name : Entity_Id;
9819 FF : constant Entity_Id := First_Formal (S);
9820 NF : constant Entity_Id := Next_Formal (FF);
9823 -- Check that equality was properly defined, ignore call if not
9830 A : constant Entity_Id :=
9831 Make_Defining_Identifier (Sloc (FF),
9832 Chars => Chars (FF));
9834 B : constant Entity_Id :=
9835 Make_Defining_Identifier (Sloc (NF),
9836 Chars => Chars (NF));
9839 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9841 Formals := New_List (
9842 Make_Parameter_Specification (Loc,
9843 Defining_Identifier => A,
9845 New_Occurrence_Of (Etype (First_Formal (S)),
9846 Sloc (Etype (First_Formal (S))))),
9848 Make_Parameter_Specification (Loc,
9849 Defining_Identifier => B,
9851 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9852 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9855 Make_Subprogram_Declaration (Loc,
9857 Make_Function_Specification (Loc,
9858 Defining_Unit_Name => Op_Name,
9859 Parameter_Specifications => Formals,
9860 Result_Definition =>
9861 New_Occurrence_Of (Standard_Boolean, Loc)));
9863 -- Insert inequality right after equality if it is explicit or after
9864 -- the derived type when implicit. These entities are created only
9865 -- for visibility purposes, and eventually replaced in the course
9866 -- of expansion, so they do not need to be attached to the tree and
9867 -- seen by the back-end. Keeping them internal also avoids spurious
9868 -- freezing problems. The declaration is inserted in the tree for
9869 -- analysis, and removed afterwards. If the equality operator comes
9870 -- from an explicit declaration, attach the inequality immediately
9871 -- after. Else the equality is inherited from a derived type
9872 -- declaration, so insert inequality after that declaration.
9874 if No (Alias (S)) then
9875 Insert_After (Unit_Declaration_Node (S), Decl);
9876 elsif Is_List_Member (Parent (S)) then
9877 Insert_After (Parent (S), Decl);
9879 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9882 Mark_Rewrite_Insertion (Decl);
9883 Set_Is_Intrinsic_Subprogram (Op_Name);
9886 Set_Has_Completion (Op_Name);
9887 Set_Corresponding_Equality (Op_Name, S);
9888 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9890 end Make_Inequality_Operator;
9892 ----------------------
9893 -- May_Need_Actuals --
9894 ----------------------
9896 procedure May_Need_Actuals (Fun : Entity_Id) is
9901 F := First_Formal (Fun);
9903 while Present (F) loop
9904 if No (Default_Value (F)) then
9912 Set_Needs_No_Actuals (Fun, B);
9913 end May_Need_Actuals;
9915 ---------------------
9916 -- Mode_Conformant --
9917 ---------------------
9919 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9922 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9924 end Mode_Conformant;
9926 ---------------------------
9927 -- New_Overloaded_Entity --
9928 ---------------------------
9930 procedure New_Overloaded_Entity
9932 Derived_Type : Entity_Id := Empty)
9934 Overridden_Subp : Entity_Id := Empty;
9935 -- Set if the current scope has an operation that is type-conformant
9936 -- with S, and becomes hidden by S.
9938 Is_Primitive_Subp : Boolean;
9939 -- Set to True if the new subprogram is primitive
9942 -- Entity that S overrides
9944 procedure Check_For_Primitive_Subprogram
9945 (Is_Primitive : out Boolean;
9946 Is_Overriding : Boolean := False);
9947 -- If the subprogram being analyzed is a primitive operation of the type
9948 -- of a formal or result, set the Has_Primitive_Operations flag on the
9949 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9950 -- corresponding flag on the entity itself for later use.
9952 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9953 -- True if a) E is a subprogram whose first formal is a concurrent type
9954 -- defined in the scope of E that has some entry or subprogram whose
9955 -- profile matches E, or b) E is an internally built dispatching
9956 -- subprogram of a protected type and there is a matching subprogram
9957 -- defined in the enclosing scope of the protected type, or c) E is
9958 -- an entry of a synchronized type and a matching procedure has been
9959 -- previously defined in the enclosing scope of the synchronized type.
9961 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9962 -- Check that E is declared in the private part of the current package,
9963 -- or in the package body, where it may hide a previous declaration.
9964 -- We can't use In_Private_Part by itself because this flag is also
9965 -- set when freezing entities, so we must examine the place of the
9966 -- declaration in the tree, and recognize wrapper packages as well.
9968 function Is_Overriding_Alias
9970 New_E : Entity_Id) return Boolean;
9971 -- Check whether new subprogram and old subprogram are both inherited
9972 -- from subprograms that have distinct dispatch table entries. This can
9973 -- occur with derivations from instances with accidental homonyms. The
9974 -- function is conservative given that the converse is only true within
9975 -- instances that contain accidental overloadings.
9977 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9978 -- Report conflict between entities S and E
9980 ------------------------------------
9981 -- Check_For_Primitive_Subprogram --
9982 ------------------------------------
9984 procedure Check_For_Primitive_Subprogram
9985 (Is_Primitive : out Boolean;
9986 Is_Overriding : Boolean := False)
9992 function Visible_Part_Type (T : Entity_Id) return Boolean;
9993 -- Returns true if T is declared in the visible part of the current
9994 -- package scope; otherwise returns false. Assumes that T is declared
9997 procedure Check_Private_Overriding (T : Entity_Id);
9998 -- Checks that if a primitive abstract subprogram of a visible
9999 -- abstract type is declared in a private part, then it must override
10000 -- an abstract subprogram declared in the visible part. Also checks
10001 -- that if a primitive function with a controlling result is declared
10002 -- in a private part, then it must override a function declared in
10003 -- the visible part.
10005 ------------------------------
10006 -- Check_Private_Overriding --
10007 ------------------------------
10009 procedure Check_Private_Overriding (T : Entity_Id) is
10010 function Overrides_Private_Part_Op return Boolean;
10011 -- This detects the special case where the overriding subprogram
10012 -- is overriding a subprogram that was declared in the same
10013 -- private part. That case is illegal by 3.9.3(10).
10015 function Overrides_Visible_Function
10016 (Partial_View : Entity_Id) return Boolean;
10017 -- True if S overrides a function in the visible part. The
10018 -- overridden function could be explicitly or implicitly declared.
10020 -------------------------------
10021 -- Overrides_Private_Part_Op --
10022 -------------------------------
10024 function Overrides_Private_Part_Op return Boolean is
10025 Over_Decl : constant Node_Id :=
10026 Unit_Declaration_Node (Overridden_Operation (S));
10027 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10030 pragma Assert (Is_Overriding);
10032 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10034 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10036 return In_Same_List (Over_Decl, Subp_Decl);
10037 end Overrides_Private_Part_Op;
10039 --------------------------------
10040 -- Overrides_Visible_Function --
10041 --------------------------------
10043 function Overrides_Visible_Function
10044 (Partial_View : Entity_Id) return Boolean
10047 if not Is_Overriding or else not Has_Homonym (S) then
10051 if not Present (Partial_View) then
10055 -- Search through all the homonyms H of S in the current
10056 -- package spec, and return True if we find one that matches.
10057 -- Note that Parent (H) will be the declaration of the
10058 -- partial view of T for a match.
10061 H : Entity_Id := S;
10065 exit when not Present (H) or else Scope (H) /= Scope (S);
10069 N_Private_Extension_Declaration,
10070 N_Private_Type_Declaration)
10071 and then Defining_Identifier (Parent (H)) = Partial_View
10079 end Overrides_Visible_Function;
10081 -- Start of processing for Check_Private_Overriding
10084 if Is_Package_Or_Generic_Package (Current_Scope)
10085 and then In_Private_Part (Current_Scope)
10086 and then Visible_Part_Type (T)
10087 and then not In_Instance
10089 if Is_Abstract_Type (T)
10090 and then Is_Abstract_Subprogram (S)
10091 and then (not Is_Overriding
10092 or else not Is_Abstract_Subprogram (E)
10093 or else Overrides_Private_Part_Op)
10096 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10099 elsif Ekind (S) = E_Function then
10101 Partial_View : constant Entity_Id :=
10102 Incomplete_Or_Partial_View (T);
10105 if not Overrides_Visible_Function (Partial_View) then
10107 -- Here, S is "function ... return T;" declared in
10108 -- the private part, not overriding some visible
10109 -- operation. That's illegal in the tagged case
10110 -- (but not if the private type is untagged).
10112 if ((Present (Partial_View)
10113 and then Is_Tagged_Type (Partial_View))
10114 or else (not Present (Partial_View)
10115 and then Is_Tagged_Type (T)))
10116 and then T = Base_Type (Etype (S))
10119 ("private function with tagged result must"
10120 & " override visible-part function", S);
10122 ("\move subprogram to the visible part"
10123 & " (RM 3.9.3(10))", S);
10125 -- AI05-0073: extend this test to the case of a
10126 -- function with a controlling access result.
10128 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10129 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10131 not Is_Class_Wide_Type
10132 (Designated_Type (Etype (S)))
10133 and then Ada_Version >= Ada_2012
10136 ("private function with controlling access "
10137 & "result must override visible-part function",
10140 ("\move subprogram to the visible part"
10141 & " (RM 3.9.3(10))", S);
10147 end Check_Private_Overriding;
10149 -----------------------
10150 -- Visible_Part_Type --
10151 -----------------------
10153 function Visible_Part_Type (T : Entity_Id) return Boolean is
10154 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10157 -- If the entity is a private type, then it must be declared in a
10160 if Ekind (T) in Private_Kind then
10163 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10166 elsif Is_List_Member (Declaration_Node (T))
10167 and then List_Containing (Declaration_Node (T)) =
10168 Visible_Declarations (Specification (P))
10175 end Visible_Part_Type;
10177 -- Start of processing for Check_For_Primitive_Subprogram
10180 Is_Primitive := False;
10182 if not Comes_From_Source (S) then
10185 -- If subprogram is at library level, it is not primitive operation
10187 elsif Current_Scope = Standard_Standard then
10190 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10191 and then not In_Package_Body (Current_Scope))
10192 or else Is_Overriding
10194 -- For function, check return type
10196 if Ekind (S) = E_Function then
10197 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10198 F_Typ := Designated_Type (Etype (S));
10200 F_Typ := Etype (S);
10203 B_Typ := Base_Type (F_Typ);
10205 if Scope (B_Typ) = Current_Scope
10206 and then not Is_Class_Wide_Type (B_Typ)
10207 and then not Is_Generic_Type (B_Typ)
10209 Is_Primitive := True;
10210 Set_Has_Primitive_Operations (B_Typ);
10211 Set_Is_Primitive (S);
10212 Check_Private_Overriding (B_Typ);
10214 -- The Ghost policy in effect at the point of declaration
10215 -- or a tagged type and a primitive operation must match
10216 -- (SPARK RM 6.9(16)).
10218 Check_Ghost_Primitive (S, B_Typ);
10222 -- For all subprograms, check formals
10224 Formal := First_Formal (S);
10225 while Present (Formal) loop
10226 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10227 F_Typ := Designated_Type (Etype (Formal));
10229 F_Typ := Etype (Formal);
10232 B_Typ := Base_Type (F_Typ);
10234 if Ekind (B_Typ) = E_Access_Subtype then
10235 B_Typ := Base_Type (B_Typ);
10238 if Scope (B_Typ) = Current_Scope
10239 and then not Is_Class_Wide_Type (B_Typ)
10240 and then not Is_Generic_Type (B_Typ)
10242 Is_Primitive := True;
10243 Set_Is_Primitive (S);
10244 Set_Has_Primitive_Operations (B_Typ);
10245 Check_Private_Overriding (B_Typ);
10247 -- The Ghost policy in effect at the point of declaration
10248 -- of a tagged type and a primitive operation must match
10249 -- (SPARK RM 6.9(16)).
10251 Check_Ghost_Primitive (S, B_Typ);
10254 Next_Formal (Formal);
10257 -- Special case: An equality function can be redefined for a type
10258 -- occurring in a declarative part, and won't otherwise be treated as
10259 -- a primitive because it doesn't occur in a package spec and doesn't
10260 -- override an inherited subprogram. It's important that we mark it
10261 -- primitive so it can be returned by Collect_Primitive_Operations
10262 -- and be used in composing the equality operation of later types
10263 -- that have a component of the type.
10265 elsif Chars (S) = Name_Op_Eq
10266 and then Etype (S) = Standard_Boolean
10268 B_Typ := Base_Type (Etype (First_Formal (S)));
10270 if Scope (B_Typ) = Current_Scope
10272 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10273 and then not Is_Limited_Type (B_Typ)
10275 Is_Primitive := True;
10276 Set_Is_Primitive (S);
10277 Set_Has_Primitive_Operations (B_Typ);
10278 Check_Private_Overriding (B_Typ);
10280 -- The Ghost policy in effect at the point of declaration of a
10281 -- tagged type and a primitive operation must match
10282 -- (SPARK RM 6.9(16)).
10284 Check_Ghost_Primitive (S, B_Typ);
10287 end Check_For_Primitive_Subprogram;
10289 --------------------------------------
10290 -- Has_Matching_Entry_Or_Subprogram --
10291 --------------------------------------
10293 function Has_Matching_Entry_Or_Subprogram
10294 (E : Entity_Id) return Boolean
10296 function Check_Conforming_Parameters
10297 (E1_Param : Node_Id;
10298 E2_Param : Node_Id) return Boolean;
10299 -- Starting from the given parameters, check that all the parameters
10300 -- of two entries or subprograms are subtype conformant. Used to skip
10301 -- the check on the controlling argument.
10303 function Matching_Entry_Or_Subprogram
10304 (Conc_Typ : Entity_Id;
10305 Subp : Entity_Id) return Entity_Id;
10306 -- Return the first entry or subprogram of the given concurrent type
10307 -- whose name matches the name of Subp and has a profile conformant
10308 -- with Subp; return Empty if not found.
10310 function Matching_Dispatching_Subprogram
10311 (Conc_Typ : Entity_Id;
10312 Ent : Entity_Id) return Entity_Id;
10313 -- Return the first dispatching primitive of Conc_Type defined in the
10314 -- enclosing scope of Conc_Type (i.e. before the full definition of
10315 -- this concurrent type) whose name matches the entry Ent and has a
10316 -- profile conformant with the profile of the corresponding (not yet
10317 -- built) dispatching primitive of Ent; return Empty if not found.
10319 function Matching_Original_Protected_Subprogram
10320 (Prot_Typ : Entity_Id;
10321 Subp : Entity_Id) return Entity_Id;
10322 -- Return the first subprogram defined in the enclosing scope of
10323 -- Prot_Typ (before the full definition of this protected type)
10324 -- whose name matches the original name of Subp and has a profile
10325 -- conformant with the profile of Subp; return Empty if not found.
10327 ---------------------------------
10328 -- Check_Conforming_Parameters --
10329 ---------------------------------
10331 function Check_Conforming_Parameters
10332 (E1_Param : Node_Id;
10333 E2_Param : Node_Id) return Boolean
10335 Param_E1 : Node_Id := E1_Param;
10336 Param_E2 : Node_Id := E2_Param;
10339 while Present (Param_E1) and then Present (Param_E2) loop
10340 if Ekind (Defining_Identifier (Param_E1)) /=
10341 Ekind (Defining_Identifier (Param_E2))
10344 (Find_Parameter_Type (Param_E1),
10345 Find_Parameter_Type (Param_E2),
10346 Subtype_Conformant)
10355 -- The candidate is not valid if one of the two lists contains
10356 -- more parameters than the other
10358 return No (Param_E1) and then No (Param_E2);
10359 end Check_Conforming_Parameters;
10361 ----------------------------------
10362 -- Matching_Entry_Or_Subprogram --
10363 ----------------------------------
10365 function Matching_Entry_Or_Subprogram
10366 (Conc_Typ : Entity_Id;
10367 Subp : Entity_Id) return Entity_Id
10372 E := First_Entity (Conc_Typ);
10373 while Present (E) loop
10374 if Chars (Subp) = Chars (E)
10375 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10377 Check_Conforming_Parameters
10378 (First (Parameter_Specifications (Parent (E))),
10379 Next (First (Parameter_Specifications (Parent (Subp)))))
10388 end Matching_Entry_Or_Subprogram;
10390 -------------------------------------
10391 -- Matching_Dispatching_Subprogram --
10392 -------------------------------------
10394 function Matching_Dispatching_Subprogram
10395 (Conc_Typ : Entity_Id;
10396 Ent : Entity_Id) return Entity_Id
10401 -- Search for entities in the enclosing scope of this synchonized
10404 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10405 Push_Scope (Scope (Conc_Typ));
10406 E := Current_Entity_In_Scope (Ent);
10409 while Present (E) loop
10410 if Scope (E) = Scope (Conc_Typ)
10411 and then Comes_From_Source (E)
10412 and then Ekind (E) = E_Procedure
10413 and then Present (First_Entity (E))
10414 and then Is_Controlling_Formal (First_Entity (E))
10415 and then Etype (First_Entity (E)) = Conc_Typ
10417 Check_Conforming_Parameters
10418 (First (Parameter_Specifications (Parent (Ent))),
10419 Next (First (Parameter_Specifications (Parent (E)))))
10428 end Matching_Dispatching_Subprogram;
10430 --------------------------------------------
10431 -- Matching_Original_Protected_Subprogram --
10432 --------------------------------------------
10434 function Matching_Original_Protected_Subprogram
10435 (Prot_Typ : Entity_Id;
10436 Subp : Entity_Id) return Entity_Id
10438 ICF : constant Boolean :=
10439 Is_Controlling_Formal (First_Entity (Subp));
10443 -- Temporarily decorate the first parameter of Subp as controlling
10444 -- formal, required to invoke Subtype_Conformant.
10446 Set_Is_Controlling_Formal (First_Entity (Subp));
10449 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10451 while Present (E) loop
10452 if Scope (E) = Scope (Prot_Typ)
10453 and then Comes_From_Source (E)
10454 and then Ekind (Subp) = Ekind (E)
10455 and then Present (First_Entity (E))
10456 and then Is_Controlling_Formal (First_Entity (E))
10457 and then Etype (First_Entity (E)) = Prot_Typ
10458 and then Subtype_Conformant (Subp, E,
10459 Skip_Controlling_Formals => True)
10461 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10468 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10471 end Matching_Original_Protected_Subprogram;
10473 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10476 -- Case 1: E is a subprogram whose first formal is a concurrent type
10477 -- defined in the scope of E that has an entry or subprogram whose
10478 -- profile matches E.
10480 if Comes_From_Source (E)
10481 and then Is_Subprogram (E)
10482 and then Present (First_Entity (E))
10483 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10486 Scope (Corresponding_Concurrent_Type
10487 (Etype (First_Entity (E))))
10490 (Matching_Entry_Or_Subprogram
10491 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10494 Report_Conflict (E,
10495 Matching_Entry_Or_Subprogram
10496 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10501 -- Case 2: E is an internally built dispatching subprogram of a
10502 -- protected type and there is a subprogram defined in the enclosing
10503 -- scope of the protected type that has the original name of E and
10504 -- its profile is conformant with the profile of E. We check the
10505 -- name of the original protected subprogram associated with E since
10506 -- the expander builds dispatching primitives of protected functions
10507 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10509 elsif not Comes_From_Source (E)
10510 and then Is_Subprogram (E)
10511 and then Present (First_Entity (E))
10512 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10513 and then Present (Original_Protected_Subprogram (E))
10516 (Matching_Original_Protected_Subprogram
10517 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10520 Report_Conflict (E,
10521 Matching_Original_Protected_Subprogram
10522 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10526 -- Case 3: E is an entry of a synchronized type and a matching
10527 -- procedure has been previously defined in the enclosing scope
10528 -- of the synchronized type.
10530 elsif Comes_From_Source (E)
10531 and then Ekind (E) = E_Entry
10533 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10535 Report_Conflict (E,
10536 Matching_Dispatching_Subprogram (Current_Scope, E));
10541 end Has_Matching_Entry_Or_Subprogram;
10543 ----------------------------
10544 -- Is_Private_Declaration --
10545 ----------------------------
10547 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10548 Decl : constant Node_Id := Unit_Declaration_Node (E);
10549 Priv_Decls : List_Id;
10552 if Is_Package_Or_Generic_Package (Current_Scope)
10553 and then In_Private_Part (Current_Scope)
10556 Private_Declarations (Package_Specification (Current_Scope));
10558 return In_Package_Body (Current_Scope)
10560 (Is_List_Member (Decl)
10561 and then List_Containing (Decl) = Priv_Decls)
10562 or else (Nkind (Parent (Decl)) = N_Package_Specification
10564 Is_Compilation_Unit
10565 (Defining_Entity (Parent (Decl)))
10566 and then List_Containing (Parent (Parent (Decl))) =
10571 end Is_Private_Declaration;
10573 --------------------------
10574 -- Is_Overriding_Alias --
10575 --------------------------
10577 function Is_Overriding_Alias
10578 (Old_E : Entity_Id;
10579 New_E : Entity_Id) return Boolean
10581 AO : constant Entity_Id := Alias (Old_E);
10582 AN : constant Entity_Id := Alias (New_E);
10585 return Scope (AO) /= Scope (AN)
10586 or else No (DTC_Entity (AO))
10587 or else No (DTC_Entity (AN))
10588 or else DT_Position (AO) = DT_Position (AN);
10589 end Is_Overriding_Alias;
10591 ---------------------
10592 -- Report_Conflict --
10593 ---------------------
10595 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10597 Error_Msg_Sloc := Sloc (E);
10599 -- Generate message, with useful additional warning if in generic
10601 if Is_Generic_Unit (E) then
10602 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10603 Error_Msg_N ("\& conflicts with declaration#", S);
10605 Error_Msg_N ("& conflicts with declaration#", S);
10607 end Report_Conflict;
10609 -- Start of processing for New_Overloaded_Entity
10612 -- We need to look for an entity that S may override. This must be a
10613 -- homonym in the current scope, so we look for the first homonym of
10614 -- S in the current scope as the starting point for the search.
10616 E := Current_Entity_In_Scope (S);
10618 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10619 -- They are directly added to the list of primitive operations of
10620 -- Derived_Type, unless this is a rederivation in the private part
10621 -- of an operation that was already derived in the visible part of
10622 -- the current package.
10624 if Ada_Version >= Ada_2005
10625 and then Present (Derived_Type)
10626 and then Present (Alias (S))
10627 and then Is_Dispatching_Operation (Alias (S))
10628 and then Present (Find_Dispatching_Type (Alias (S)))
10629 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10631 -- For private types, when the full-view is processed we propagate to
10632 -- the full view the non-overridden entities whose attribute "alias"
10633 -- references an interface primitive. These entities were added by
10634 -- Derive_Subprograms to ensure that interface primitives are
10637 -- Inside_Freeze_Actions is non zero when S corresponds with an
10638 -- internal entity that links an interface primitive with its
10639 -- covering primitive through attribute Interface_Alias (see
10640 -- Add_Internal_Interface_Entities).
10642 if Inside_Freezing_Actions = 0
10643 and then Is_Package_Or_Generic_Package (Current_Scope)
10644 and then In_Private_Part (Current_Scope)
10645 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10646 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10647 and then Full_View (Defining_Identifier (Parent (E)))
10648 = Defining_Identifier (Parent (S))
10649 and then Alias (E) = Alias (S)
10651 Check_Operation_From_Private_View (S, E);
10652 Set_Is_Dispatching_Operation (S);
10657 Enter_Overloaded_Entity (S);
10658 Check_Dispatching_Operation (S, Empty);
10659 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10665 -- For synchronized types check conflicts of this entity with previously
10666 -- defined entities.
10668 if Ada_Version >= Ada_2005
10669 and then Has_Matching_Entry_Or_Subprogram (S)
10674 -- If there is no homonym then this is definitely not overriding
10677 Enter_Overloaded_Entity (S);
10678 Check_Dispatching_Operation (S, Empty);
10679 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10681 -- If subprogram has an explicit declaration, check whether it has an
10682 -- overriding indicator.
10684 if Comes_From_Source (S) then
10685 Check_Synchronized_Overriding (S, Overridden_Subp);
10687 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10688 -- it may have overridden some hidden inherited primitive. Update
10689 -- Overridden_Subp to avoid spurious errors when checking the
10690 -- overriding indicator.
10692 if Ada_Version >= Ada_2012
10693 and then No (Overridden_Subp)
10694 and then Is_Dispatching_Operation (S)
10695 and then Present (Overridden_Operation (S))
10697 Overridden_Subp := Overridden_Operation (S);
10700 Check_Overriding_Indicator
10701 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10703 -- The Ghost policy in effect at the point of declaration of a
10704 -- parent subprogram and an overriding subprogram must match
10705 -- (SPARK RM 6.9(17)).
10707 Check_Ghost_Overriding (S, Overridden_Subp);
10710 -- If there is a homonym that is not overloadable, then we have an
10711 -- error, except for the special cases checked explicitly below.
10713 elsif not Is_Overloadable (E) then
10715 -- Check for spurious conflict produced by a subprogram that has the
10716 -- same name as that of the enclosing generic package. The conflict
10717 -- occurs within an instance, between the subprogram and the renaming
10718 -- declaration for the package. After the subprogram, the package
10719 -- renaming declaration becomes hidden.
10721 if Ekind (E) = E_Package
10722 and then Present (Renamed_Object (E))
10723 and then Renamed_Object (E) = Current_Scope
10724 and then Nkind (Parent (Renamed_Object (E))) =
10725 N_Package_Specification
10726 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10729 Set_Is_Immediately_Visible (E, False);
10730 Enter_Overloaded_Entity (S);
10731 Set_Homonym (S, Homonym (E));
10732 Check_Dispatching_Operation (S, Empty);
10733 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10735 -- If the subprogram is implicit it is hidden by the previous
10736 -- declaration. However if it is dispatching, it must appear in the
10737 -- dispatch table anyway, because it can be dispatched to even if it
10738 -- cannot be called directly.
10740 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10741 Set_Scope (S, Current_Scope);
10743 if Is_Dispatching_Operation (Alias (S)) then
10744 Check_Dispatching_Operation (S, Empty);
10750 Report_Conflict (S, E);
10754 -- E exists and is overloadable
10757 Check_Synchronized_Overriding (S, Overridden_Subp);
10759 -- Loop through E and its homonyms to determine if any of them is
10760 -- the candidate for overriding by S.
10762 while Present (E) loop
10764 -- Definitely not interesting if not in the current scope
10766 if Scope (E) /= Current_Scope then
10769 -- A function can overload the name of an abstract state. The
10770 -- state can be viewed as a function with a profile that cannot
10771 -- be matched by anything.
10773 elsif Ekind (S) = E_Function
10774 and then Ekind (E) = E_Abstract_State
10776 Enter_Overloaded_Entity (S);
10779 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10780 -- procedures locate the internally generated spec. We enforce
10781 -- mode conformance since a tagged type may inherit from
10782 -- interfaces several null primitives which differ only in
10783 -- the mode of the formals.
10785 elsif not Comes_From_Source (S)
10786 and then Is_Null_Procedure (S)
10787 and then not Mode_Conformant (E, S)
10791 -- Check if we have type conformance
10793 elsif Type_Conformant (E, S) then
10795 -- If the old and new entities have the same profile and one
10796 -- is not the body of the other, then this is an error, unless
10797 -- one of them is implicitly declared.
10799 -- There are some cases when both can be implicit, for example
10800 -- when both a literal and a function that overrides it are
10801 -- inherited in a derivation, or when an inherited operation
10802 -- of a tagged full type overrides the inherited operation of
10803 -- a private extension. Ada 83 had a special rule for the
10804 -- literal case. In Ada 95, the later implicit operation hides
10805 -- the former, and the literal is always the former. In the
10806 -- odd case where both are derived operations declared at the
10807 -- same point, both operations should be declared, and in that
10808 -- case we bypass the following test and proceed to the next
10809 -- part. This can only occur for certain obscure cases in
10810 -- instances, when an operation on a type derived from a formal
10811 -- private type does not override a homograph inherited from
10812 -- the actual. In subsequent derivations of such a type, the
10813 -- DT positions of these operations remain distinct, if they
10816 if Present (Alias (S))
10817 and then (No (Alias (E))
10818 or else Comes_From_Source (E)
10819 or else Is_Abstract_Subprogram (S)
10821 (Is_Dispatching_Operation (E)
10822 and then Is_Overriding_Alias (E, S)))
10823 and then Ekind (E) /= E_Enumeration_Literal
10825 -- When an derived operation is overloaded it may be due to
10826 -- the fact that the full view of a private extension
10827 -- re-inherits. It has to be dealt with.
10829 if Is_Package_Or_Generic_Package (Current_Scope)
10830 and then In_Private_Part (Current_Scope)
10832 Check_Operation_From_Private_View (S, E);
10835 -- In any case the implicit operation remains hidden by the
10836 -- existing declaration, which is overriding. Indicate that
10837 -- E overrides the operation from which S is inherited.
10839 if Present (Alias (S)) then
10840 Set_Overridden_Operation (E, Alias (S));
10841 Inherit_Subprogram_Contract (E, Alias (S));
10844 Set_Overridden_Operation (E, S);
10845 Inherit_Subprogram_Contract (E, S);
10848 if Comes_From_Source (E) then
10849 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10851 -- The Ghost policy in effect at the point of declaration
10852 -- of a parent subprogram and an overriding subprogram
10853 -- must match (SPARK RM 6.9(17)).
10855 Check_Ghost_Overriding (E, S);
10860 -- Within an instance, the renaming declarations for actual
10861 -- subprograms may become ambiguous, but they do not hide each
10864 elsif Ekind (E) /= E_Entry
10865 and then not Comes_From_Source (E)
10866 and then not Is_Generic_Instance (E)
10867 and then (Present (Alias (E))
10868 or else Is_Intrinsic_Subprogram (E))
10869 and then (not In_Instance
10870 or else No (Parent (E))
10871 or else Nkind (Unit_Declaration_Node (E)) /=
10872 N_Subprogram_Renaming_Declaration)
10874 -- A subprogram child unit is not allowed to override an
10875 -- inherited subprogram (10.1.1(20)).
10877 if Is_Child_Unit (S) then
10879 ("child unit overrides inherited subprogram in parent",
10884 if Is_Non_Overriding_Operation (E, S) then
10885 Enter_Overloaded_Entity (S);
10887 if No (Derived_Type)
10888 or else Is_Tagged_Type (Derived_Type)
10890 Check_Dispatching_Operation (S, Empty);
10896 -- E is a derived operation or an internal operator which
10897 -- is being overridden. Remove E from further visibility.
10898 -- Furthermore, if E is a dispatching operation, it must be
10899 -- replaced in the list of primitive operations of its type
10900 -- (see Override_Dispatching_Operation).
10902 Overridden_Subp := E;
10904 -- It is possible for E to be in the current scope and
10905 -- yet not in the entity chain. This can only occur in a
10906 -- generic context where E is an implicit concatenation
10907 -- in the formal part, because in a generic body the
10908 -- entity chain starts with the formals.
10910 -- In GNATprove mode, a wrapper for an operation with
10911 -- axiomatization may be a homonym of another declaration
10912 -- for an actual subprogram (needs refinement ???).
10914 if No (Prev_Entity (E)) then
10916 and then GNATprove_Mode
10918 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10919 N_Subprogram_Renaming_Declaration
10923 pragma Assert (Chars (E) = Name_Op_Concat);
10928 -- E must be removed both from the entity_list of the
10929 -- current scope, and from the visibility chain.
10931 if Debug_Flag_E then
10932 Write_Str ("Override implicit operation ");
10933 Write_Int (Int (E));
10937 -- If E is a predefined concatenation, it stands for four
10938 -- different operations. As a result, a single explicit
10939 -- declaration does not hide it. In a possible ambiguous
10940 -- situation, Disambiguate chooses the user-defined op,
10941 -- so it is correct to retain the previous internal one.
10943 if Chars (E) /= Name_Op_Concat
10944 or else Ekind (E) /= E_Operator
10946 -- For nondispatching derived operations that are
10947 -- overridden by a subprogram declared in the private
10948 -- part of a package, we retain the derived subprogram
10949 -- but mark it as not immediately visible. If the
10950 -- derived operation was declared in the visible part
10951 -- then this ensures that it will still be visible
10952 -- outside the package with the proper signature
10953 -- (calls from outside must also be directed to this
10954 -- version rather than the overriding one, unlike the
10955 -- dispatching case). Calls from inside the package
10956 -- will still resolve to the overriding subprogram
10957 -- since the derived one is marked as not visible
10958 -- within the package.
10960 -- If the private operation is dispatching, we achieve
10961 -- the overriding by keeping the implicit operation
10962 -- but setting its alias to be the overriding one. In
10963 -- this fashion the proper body is executed in all
10964 -- cases, but the original signature is used outside
10967 -- If the overriding is not in the private part, we
10968 -- remove the implicit operation altogether.
10970 if Is_Private_Declaration (S) then
10971 if not Is_Dispatching_Operation (E) then
10972 Set_Is_Immediately_Visible (E, False);
10974 -- Work done in Override_Dispatching_Operation, so
10975 -- nothing else needs to be done here.
10981 Remove_Entity_And_Homonym (E);
10985 Enter_Overloaded_Entity (S);
10987 -- For entities generated by Derive_Subprograms the
10988 -- overridden operation is the inherited primitive
10989 -- (which is available through the attribute alias).
10991 if not (Comes_From_Source (E))
10992 and then Is_Dispatching_Operation (E)
10993 and then Find_Dispatching_Type (E) =
10994 Find_Dispatching_Type (S)
10995 and then Present (Alias (E))
10996 and then Comes_From_Source (Alias (E))
10998 Set_Overridden_Operation (S, Alias (E));
10999 Inherit_Subprogram_Contract (S, Alias (E));
11001 -- Normal case of setting entity as overridden
11003 -- Note: Static_Initialization and Overridden_Operation
11004 -- attributes use the same field in subprogram entities.
11005 -- Static_Initialization is only defined for internal
11006 -- initialization procedures, where Overridden_Operation
11007 -- is irrelevant. Therefore the setting of this attribute
11008 -- must check whether the target is an init_proc.
11010 elsif not Is_Init_Proc (S) then
11011 Set_Overridden_Operation (S, E);
11012 Inherit_Subprogram_Contract (S, E);
11015 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11017 -- The Ghost policy in effect at the point of declaration
11018 -- of a parent subprogram and an overriding subprogram
11019 -- must match (SPARK RM 6.9(17)).
11021 Check_Ghost_Overriding (S, E);
11023 -- If S is a user-defined subprogram or a null procedure
11024 -- expanded to override an inherited null procedure, or a
11025 -- predefined dispatching primitive then indicate that E
11026 -- overrides the operation from which S is inherited.
11028 if Comes_From_Source (S)
11030 (Present (Parent (S))
11031 and then Nkind (Parent (S)) = N_Procedure_Specification
11032 and then Null_Present (Parent (S)))
11034 (Present (Alias (E))
11036 Is_Predefined_Dispatching_Operation (Alias (E)))
11038 if Present (Alias (E)) then
11039 Set_Overridden_Operation (S, Alias (E));
11040 Inherit_Subprogram_Contract (S, Alias (E));
11044 if Is_Dispatching_Operation (E) then
11046 -- An overriding dispatching subprogram inherits the
11047 -- convention of the overridden subprogram (AI-117).
11049 Set_Convention (S, Convention (E));
11050 Check_Dispatching_Operation (S, E);
11053 Check_Dispatching_Operation (S, Empty);
11056 Check_For_Primitive_Subprogram
11057 (Is_Primitive_Subp, Is_Overriding => True);
11058 goto Check_Inequality;
11060 -- Apparent redeclarations in instances can occur when two
11061 -- formal types get the same actual type. The subprograms in
11062 -- in the instance are legal, even if not callable from the
11063 -- outside. Calls from within are disambiguated elsewhere.
11064 -- For dispatching operations in the visible part, the usual
11065 -- rules apply, and operations with the same profile are not
11066 -- legal (B830001).
11068 elsif (In_Instance_Visible_Part
11069 and then not Is_Dispatching_Operation (E))
11070 or else In_Instance_Not_Visible
11074 -- Here we have a real error (identical profile)
11077 Error_Msg_Sloc := Sloc (E);
11079 -- Avoid cascaded errors if the entity appears in
11080 -- subsequent calls.
11082 Set_Scope (S, Current_Scope);
11084 -- Generate error, with extra useful warning for the case
11085 -- of a generic instance with no completion.
11087 if Is_Generic_Instance (S)
11088 and then not Has_Completion (E)
11091 ("instantiation cannot provide body for&", S);
11092 Error_Msg_N ("\& conflicts with declaration#", S);
11094 Error_Msg_N ("& conflicts with declaration#", S);
11101 -- If one subprogram has an access parameter and the other
11102 -- a parameter of an access type, calls to either might be
11103 -- ambiguous. Verify that parameters match except for the
11104 -- access parameter.
11106 if May_Hide_Profile then
11112 F1 := First_Formal (S);
11113 F2 := First_Formal (E);
11114 while Present (F1) and then Present (F2) loop
11115 if Is_Access_Type (Etype (F1)) then
11116 if not Is_Access_Type (Etype (F2))
11117 or else not Conforming_Types
11118 (Designated_Type (Etype (F1)),
11119 Designated_Type (Etype (F2)),
11122 May_Hide_Profile := False;
11126 not Conforming_Types
11127 (Etype (F1), Etype (F2), Type_Conformant)
11129 May_Hide_Profile := False;
11136 if May_Hide_Profile
11140 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11149 -- On exit, we know that S is a new entity
11151 Enter_Overloaded_Entity (S);
11152 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11153 Check_Overriding_Indicator
11154 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11156 -- The Ghost policy in effect at the point of declaration of a parent
11157 -- subprogram and an overriding subprogram must match
11158 -- (SPARK RM 6.9(17)).
11160 Check_Ghost_Overriding (S, Overridden_Subp);
11162 -- Overloading is not allowed in SPARK, except for operators
11164 if Nkind (S) /= N_Defining_Operator_Symbol then
11165 Error_Msg_Sloc := Sloc (Homonym (S));
11166 Check_SPARK_05_Restriction
11167 ("overloading not allowed with entity#", S);
11170 -- If S is a derived operation for an untagged type then by
11171 -- definition it's not a dispatching operation (even if the parent
11172 -- operation was dispatching), so Check_Dispatching_Operation is not
11173 -- called in that case.
11175 if No (Derived_Type)
11176 or else Is_Tagged_Type (Derived_Type)
11178 Check_Dispatching_Operation (S, Empty);
11182 -- If this is a user-defined equality operator that is not a derived
11183 -- subprogram, create the corresponding inequality. If the operation is
11184 -- dispatching, the expansion is done elsewhere, and we do not create
11185 -- an explicit inequality operation.
11187 <<Check_Inequality>>
11188 if Chars (S) = Name_Op_Eq
11189 and then Etype (S) = Standard_Boolean
11190 and then Present (Parent (S))
11191 and then not Is_Dispatching_Operation (S)
11193 Make_Inequality_Operator (S);
11194 Check_Untagged_Equality (S);
11196 end New_Overloaded_Entity;
11198 ----------------------------------
11199 -- Preanalyze_Formal_Expression --
11200 ----------------------------------
11202 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id) is
11203 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
11205 In_Spec_Expression := True;
11206 Preanalyze_With_Freezing_And_Resolve (N, T);
11207 In_Spec_Expression := Save_In_Spec_Expression;
11208 end Preanalyze_Formal_Expression;
11210 ---------------------
11211 -- Process_Formals --
11212 ---------------------
11214 procedure Process_Formals
11216 Related_Nod : Node_Id)
11218 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11219 -- Determine whether an access type designates a type coming from a
11222 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11223 -- Check whether the default has a class-wide type. After analysis the
11224 -- default has the type of the formal, so we must also check explicitly
11225 -- for an access attribute.
11227 ----------------------------------
11228 -- Designates_From_Limited_With --
11229 ----------------------------------
11231 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11232 Desig : Entity_Id := Typ;
11235 if Is_Access_Type (Desig) then
11236 Desig := Directly_Designated_Type (Desig);
11239 if Is_Class_Wide_Type (Desig) then
11240 Desig := Root_Type (Desig);
11244 Ekind (Desig) = E_Incomplete_Type
11245 and then From_Limited_With (Desig);
11246 end Designates_From_Limited_With;
11248 ---------------------------
11249 -- Is_Class_Wide_Default --
11250 ---------------------------
11252 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11254 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11255 or else (Nkind (D) = N_Attribute_Reference
11256 and then Attribute_Name (D) = Name_Access
11257 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11258 end Is_Class_Wide_Default;
11262 Context : constant Node_Id := Parent (Parent (T));
11264 Formal : Entity_Id;
11265 Formal_Type : Entity_Id;
11266 Param_Spec : Node_Id;
11269 Num_Out_Params : Nat := 0;
11270 First_Out_Param : Entity_Id := Empty;
11271 -- Used for setting Is_Only_Out_Parameter
11273 -- Start of processing for Process_Formals
11276 -- In order to prevent premature use of the formals in the same formal
11277 -- part, the Ekind is left undefined until all default expressions are
11278 -- analyzed. The Ekind is established in a separate loop at the end.
11280 Param_Spec := First (T);
11281 while Present (Param_Spec) loop
11282 Formal := Defining_Identifier (Param_Spec);
11283 Set_Never_Set_In_Source (Formal, True);
11284 Enter_Name (Formal);
11286 -- Case of ordinary parameters
11288 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11289 Find_Type (Parameter_Type (Param_Spec));
11290 Ptype := Parameter_Type (Param_Spec);
11292 if Ptype = Error then
11296 Formal_Type := Entity (Ptype);
11298 if Is_Incomplete_Type (Formal_Type)
11300 (Is_Class_Wide_Type (Formal_Type)
11301 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11303 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11304 -- primitive operations, as long as their completion is
11305 -- in the same declarative part. If in the private part
11306 -- this means that the type cannot be a Taft-amendment type.
11307 -- Check is done on package exit. For access to subprograms,
11308 -- the use is legal for Taft-amendment types.
11310 -- Ada 2012: tagged incomplete types are allowed as generic
11311 -- formal types. They do not introduce dependencies and the
11312 -- corresponding generic subprogram does not have a delayed
11313 -- freeze, because it does not need a freeze node. However,
11314 -- it is still the case that untagged incomplete types cannot
11315 -- be Taft-amendment types and must be completed in private
11316 -- part, so the subprogram must appear in the list of private
11317 -- dependents of the type.
11319 if Is_Tagged_Type (Formal_Type)
11320 or else (Ada_Version >= Ada_2012
11321 and then not From_Limited_With (Formal_Type)
11322 and then not Is_Generic_Type (Formal_Type))
11324 if Ekind (Scope (Current_Scope)) = E_Package
11325 and then not Is_Generic_Type (Formal_Type)
11326 and then not Is_Class_Wide_Type (Formal_Type)
11329 (Parent (T), N_Access_Function_Definition,
11330 N_Access_Procedure_Definition)
11332 Append_Elmt (Current_Scope,
11333 Private_Dependents (Base_Type (Formal_Type)));
11335 -- Freezing is delayed to ensure that Register_Prim
11336 -- will get called for this operation, which is needed
11337 -- in cases where static dispatch tables aren't built.
11338 -- (Note that the same is done for controlling access
11339 -- parameter cases in function Access_Definition.)
11341 if not Is_Thunk (Current_Scope) then
11342 Set_Has_Delayed_Freeze (Current_Scope);
11347 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11348 N_Access_Procedure_Definition)
11350 -- AI05-0151: Tagged incomplete types are allowed in all
11351 -- formal parts. Untagged incomplete types are not allowed
11352 -- in bodies. Limited views of either kind are not allowed
11353 -- if there is no place at which the non-limited view can
11354 -- become available.
11356 -- Incomplete formal untagged types are not allowed in
11357 -- subprogram bodies (but are legal in their declarations).
11358 -- This excludes bodies created for null procedures, which
11359 -- are basic declarations.
11361 if Is_Generic_Type (Formal_Type)
11362 and then not Is_Tagged_Type (Formal_Type)
11363 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11366 ("invalid use of formal incomplete type", Param_Spec);
11368 elsif Ada_Version >= Ada_2012 then
11369 if Is_Tagged_Type (Formal_Type)
11370 and then (not From_Limited_With (Formal_Type)
11371 or else not In_Package_Body)
11375 elsif Nkind_In (Context, N_Accept_Statement,
11376 N_Accept_Alternative,
11378 or else (Nkind (Context) = N_Subprogram_Body
11379 and then Comes_From_Source (Context))
11382 ("invalid use of untagged incomplete type &",
11383 Ptype, Formal_Type);
11388 ("invalid use of incomplete type&",
11389 Param_Spec, Formal_Type);
11391 -- Further checks on the legality of incomplete types
11392 -- in formal parts are delayed until the freeze point
11393 -- of the enclosing subprogram or access to subprogram.
11397 elsif Ekind (Formal_Type) = E_Void then
11399 ("premature use of&",
11400 Parameter_Type (Param_Spec), Formal_Type);
11403 -- Ada 2012 (AI-142): Handle aliased parameters
11405 if Ada_Version >= Ada_2012
11406 and then Aliased_Present (Param_Spec)
11408 Set_Is_Aliased (Formal);
11411 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11412 -- declaration corresponding to the null-excluding type of the
11413 -- formal in the enclosing scope. Finally, replace the parameter
11414 -- type of the formal with the internal subtype.
11416 if Ada_Version >= Ada_2005
11417 and then Null_Exclusion_Present (Param_Spec)
11419 if not Is_Access_Type (Formal_Type) then
11421 ("`NOT NULL` allowed only for an access type", Param_Spec);
11424 if Can_Never_Be_Null (Formal_Type)
11425 and then Comes_From_Source (Related_Nod)
11428 ("`NOT NULL` not allowed (& already excludes null)",
11429 Param_Spec, Formal_Type);
11433 Create_Null_Excluding_Itype
11435 Related_Nod => Related_Nod,
11436 Scope_Id => Scope (Current_Scope));
11438 -- If the designated type of the itype is an itype that is
11439 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11440 -- on the access subtype, to prevent order-of-elaboration
11441 -- issues in the backend.
11444 -- type T is access procedure;
11445 -- procedure Op (O : not null T);
11447 if Is_Itype (Directly_Designated_Type (Formal_Type))
11449 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11451 Set_Has_Delayed_Freeze (Formal_Type);
11456 -- An access formal type
11460 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11462 -- No need to continue if we already notified errors
11464 if not Present (Formal_Type) then
11468 -- Ada 2005 (AI-254)
11471 AD : constant Node_Id :=
11472 Access_To_Subprogram_Definition
11473 (Parameter_Type (Param_Spec));
11475 if Present (AD) and then Protected_Present (AD) then
11477 Replace_Anonymous_Access_To_Protected_Subprogram
11483 Set_Etype (Formal, Formal_Type);
11485 -- Deal with default expression if present
11487 Default := Expression (Param_Spec);
11489 if Present (Default) then
11490 Check_SPARK_05_Restriction
11491 ("default expression is not allowed", Default);
11493 if Out_Present (Param_Spec) then
11495 ("default initialization only allowed for IN parameters",
11499 -- Do the special preanalysis of the expression (see section on
11500 -- "Handling of Default Expressions" in the spec of package Sem).
11502 Preanalyze_Formal_Expression (Default, Formal_Type);
11504 -- An access to constant cannot be the default for
11505 -- an access parameter that is an access to variable.
11507 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11508 and then not Is_Access_Constant (Formal_Type)
11509 and then Is_Access_Type (Etype (Default))
11510 and then Is_Access_Constant (Etype (Default))
11513 ("formal that is access to variable cannot be initialized "
11514 & "with an access-to-constant expression", Default);
11517 -- Check that the designated type of an access parameter's default
11518 -- is not a class-wide type unless the parameter's designated type
11519 -- is also class-wide.
11521 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11522 and then not Designates_From_Limited_With (Formal_Type)
11523 and then Is_Class_Wide_Default (Default)
11524 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11527 ("access to class-wide expression not allowed here", Default);
11530 -- Check incorrect use of dynamically tagged expressions
11532 if Is_Tagged_Type (Formal_Type) then
11533 Check_Dynamically_Tagged_Expression
11535 Typ => Formal_Type,
11536 Related_Nod => Default);
11540 -- Ada 2005 (AI-231): Static checks
11542 if Ada_Version >= Ada_2005
11543 and then Is_Access_Type (Etype (Formal))
11544 and then Can_Never_Be_Null (Etype (Formal))
11546 Null_Exclusion_Static_Checks (Param_Spec);
11549 -- The following checks are relevant only when SPARK_Mode is on as
11550 -- these are not standard Ada legality rules.
11552 if SPARK_Mode = On then
11553 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11555 -- A function cannot have a parameter of mode IN OUT or OUT
11558 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11560 ("function cannot have parameter of mode `OUT` or "
11561 & "`IN OUT`", Formal);
11564 -- A procedure cannot have an effectively volatile formal
11565 -- parameter of mode IN because it behaves as a constant
11566 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11568 elsif Ekind (Scope (Formal)) = E_Procedure
11569 and then Ekind (Formal) = E_In_Parameter
11570 and then Is_Effectively_Volatile (Formal)
11573 ("formal parameter of mode `IN` cannot be volatile", Formal);
11581 -- If this is the formal part of a function specification, analyze the
11582 -- subtype mark in the context where the formals are visible but not
11583 -- yet usable, and may hide outer homographs.
11585 if Nkind (Related_Nod) = N_Function_Specification then
11586 Analyze_Return_Type (Related_Nod);
11589 -- Now set the kind (mode) of each formal
11591 Param_Spec := First (T);
11592 while Present (Param_Spec) loop
11593 Formal := Defining_Identifier (Param_Spec);
11594 Set_Formal_Mode (Formal);
11596 if Ekind (Formal) = E_In_Parameter then
11597 Set_Default_Value (Formal, Expression (Param_Spec));
11599 if Present (Expression (Param_Spec)) then
11600 Default := Expression (Param_Spec);
11602 if Is_Scalar_Type (Etype (Default)) then
11603 if Nkind (Parameter_Type (Param_Spec)) /=
11604 N_Access_Definition
11606 Formal_Type := Entity (Parameter_Type (Param_Spec));
11610 (Related_Nod, Parameter_Type (Param_Spec));
11613 Apply_Scalar_Range_Check (Default, Formal_Type);
11617 elsif Ekind (Formal) = E_Out_Parameter then
11618 Num_Out_Params := Num_Out_Params + 1;
11620 if Num_Out_Params = 1 then
11621 First_Out_Param := Formal;
11624 elsif Ekind (Formal) = E_In_Out_Parameter then
11625 Num_Out_Params := Num_Out_Params + 1;
11628 -- Skip remaining processing if formal type was in error
11630 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11631 goto Next_Parameter;
11634 -- Force call by reference if aliased
11637 Conv : constant Convention_Id := Convention (Etype (Formal));
11639 if Is_Aliased (Formal) then
11640 Set_Mechanism (Formal, By_Reference);
11642 -- Warn if user asked this to be passed by copy
11644 if Conv = Convention_Ada_Pass_By_Copy then
11646 ("cannot pass aliased parameter & by copy??", Formal);
11649 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11651 elsif Conv = Convention_Ada_Pass_By_Copy then
11652 Set_Mechanism (Formal, By_Copy);
11654 elsif Conv = Convention_Ada_Pass_By_Reference then
11655 Set_Mechanism (Formal, By_Reference);
11663 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11664 Set_Is_Only_Out_Parameter (First_Out_Param);
11666 end Process_Formals;
11668 ----------------------------
11669 -- Reference_Body_Formals --
11670 ----------------------------
11672 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11677 if Error_Posted (Spec) then
11681 -- Iterate over both lists. They may be of different lengths if the two
11682 -- specs are not conformant.
11684 Fs := First_Formal (Spec);
11685 Fb := First_Formal (Bod);
11686 while Present (Fs) and then Present (Fb) loop
11687 Generate_Reference (Fs, Fb, 'b');
11689 if Style_Check then
11690 Style.Check_Identifier (Fb, Fs);
11693 Set_Spec_Entity (Fb, Fs);
11694 Set_Referenced (Fs, False);
11698 end Reference_Body_Formals;
11700 -------------------------
11701 -- Set_Actual_Subtypes --
11702 -------------------------
11704 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11706 Formal : Entity_Id;
11708 First_Stmt : Node_Id := Empty;
11709 AS_Needed : Boolean;
11712 -- If this is an empty initialization procedure, no need to create
11713 -- actual subtypes (small optimization).
11715 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11718 -- Within a predicate function we do not want to generate local
11719 -- subtypes that may generate nested predicate functions.
11721 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11725 -- The subtype declarations may freeze the formals. The body generated
11726 -- for an expression function is not a freeze point, so do not emit
11727 -- these declarations (small loss of efficiency in rare cases).
11729 if Nkind (N) = N_Subprogram_Body
11730 and then Was_Expression_Function (N)
11735 Formal := First_Formal (Subp);
11736 while Present (Formal) loop
11737 T := Etype (Formal);
11739 -- We never need an actual subtype for a constrained formal
11741 if Is_Constrained (T) then
11742 AS_Needed := False;
11744 -- If we have unknown discriminants, then we do not need an actual
11745 -- subtype, or more accurately we cannot figure it out. Note that
11746 -- all class-wide types have unknown discriminants.
11748 elsif Has_Unknown_Discriminants (T) then
11749 AS_Needed := False;
11751 -- At this stage we have an unconstrained type that may need an
11752 -- actual subtype. For sure the actual subtype is needed if we have
11753 -- an unconstrained array type. However, in an instance, the type
11754 -- may appear as a subtype of the full view, while the actual is
11755 -- in fact private (in which case no actual subtype is needed) so
11756 -- check the kind of the base type.
11758 elsif Is_Array_Type (Base_Type (T)) then
11761 -- The only other case needing an actual subtype is an unconstrained
11762 -- record type which is an IN parameter (we cannot generate actual
11763 -- subtypes for the OUT or IN OUT case, since an assignment can
11764 -- change the discriminant values. However we exclude the case of
11765 -- initialization procedures, since discriminants are handled very
11766 -- specially in this context, see the section entitled "Handling of
11767 -- Discriminants" in Einfo.
11769 -- We also exclude the case of Discrim_SO_Functions (functions used
11770 -- in front-end layout mode for size/offset values), since in such
11771 -- functions only discriminants are referenced, and not only are such
11772 -- subtypes not needed, but they cannot always be generated, because
11773 -- of order of elaboration issues.
11775 elsif Is_Record_Type (T)
11776 and then Ekind (Formal) = E_In_Parameter
11777 and then Chars (Formal) /= Name_uInit
11778 and then not Is_Unchecked_Union (T)
11779 and then not Is_Discrim_SO_Function (Subp)
11783 -- All other cases do not need an actual subtype
11786 AS_Needed := False;
11789 -- Generate actual subtypes for unconstrained arrays and
11790 -- unconstrained discriminated records.
11793 if Nkind (N) = N_Accept_Statement then
11795 -- If expansion is active, the formal is replaced by a local
11796 -- variable that renames the corresponding entry of the
11797 -- parameter block, and it is this local variable that may
11798 -- require an actual subtype.
11800 if Expander_Active then
11801 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11803 Decl := Build_Actual_Subtype (T, Formal);
11806 if Present (Handled_Statement_Sequence (N)) then
11808 First (Statements (Handled_Statement_Sequence (N)));
11809 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11810 Mark_Rewrite_Insertion (Decl);
11812 -- If the accept statement has no body, there will be no
11813 -- reference to the actuals, so no need to compute actual
11820 Decl := Build_Actual_Subtype (T, Formal);
11821 Prepend (Decl, Declarations (N));
11822 Mark_Rewrite_Insertion (Decl);
11825 -- The declaration uses the bounds of an existing object, and
11826 -- therefore needs no constraint checks.
11828 Analyze (Decl, Suppress => All_Checks);
11829 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11831 -- We need to freeze manually the generated type when it is
11832 -- inserted anywhere else than in a declarative part.
11834 if Present (First_Stmt) then
11835 Insert_List_Before_And_Analyze (First_Stmt,
11836 Freeze_Entity (Defining_Identifier (Decl), N));
11838 -- Ditto if the type has a dynamic predicate, because the
11839 -- generated function will mention the actual subtype. The
11840 -- predicate may come from an explicit aspect of be inherited.
11842 elsif Has_Predicates (T) then
11843 Insert_List_Before_And_Analyze (Decl,
11844 Freeze_Entity (Defining_Identifier (Decl), N));
11847 if Nkind (N) = N_Accept_Statement
11848 and then Expander_Active
11850 Set_Actual_Subtype (Renamed_Object (Formal),
11851 Defining_Identifier (Decl));
11853 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11857 Next_Formal (Formal);
11859 end Set_Actual_Subtypes;
11861 ---------------------
11862 -- Set_Formal_Mode --
11863 ---------------------
11865 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11866 Spec : constant Node_Id := Parent (Formal_Id);
11867 Id : constant Entity_Id := Scope (Formal_Id);
11870 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11871 -- since we ensure that corresponding actuals are always valid at the
11872 -- point of the call.
11874 if Out_Present (Spec) then
11875 if Ekind_In (Id, E_Entry, E_Entry_Family)
11876 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11878 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11881 if Ekind_In (Id, E_Function, E_Generic_Function) then
11883 -- [IN] OUT parameters allowed for functions in Ada 2012
11885 if Ada_Version >= Ada_2012 then
11887 -- Even in Ada 2012 operators can only have IN parameters
11889 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11890 Error_Msg_N ("operators can only have IN parameters", Spec);
11893 if In_Present (Spec) then
11894 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11896 Set_Ekind (Formal_Id, E_Out_Parameter);
11899 -- But not in earlier versions of Ada
11902 Error_Msg_N ("functions can only have IN parameters", Spec);
11903 Set_Ekind (Formal_Id, E_In_Parameter);
11906 elsif In_Present (Spec) then
11907 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11910 Set_Ekind (Formal_Id, E_Out_Parameter);
11911 Set_Never_Set_In_Source (Formal_Id, True);
11912 Set_Is_True_Constant (Formal_Id, False);
11913 Set_Current_Value (Formal_Id, Empty);
11917 Set_Ekind (Formal_Id, E_In_Parameter);
11920 -- Set Is_Known_Non_Null for access parameters since the language
11921 -- guarantees that access parameters are always non-null. We also set
11922 -- Can_Never_Be_Null, since there is no way to change the value.
11924 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11926 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11927 -- null; In Ada 2005, only if then null_exclusion is explicit.
11929 if Ada_Version < Ada_2005
11930 or else Can_Never_Be_Null (Etype (Formal_Id))
11932 Set_Is_Known_Non_Null (Formal_Id);
11933 Set_Can_Never_Be_Null (Formal_Id);
11936 -- Ada 2005 (AI-231): Null-exclusion access subtype
11938 elsif Is_Access_Type (Etype (Formal_Id))
11939 and then Can_Never_Be_Null (Etype (Formal_Id))
11941 Set_Is_Known_Non_Null (Formal_Id);
11943 -- We can also set Can_Never_Be_Null (thus preventing some junk
11944 -- access checks) for the case of an IN parameter, which cannot
11945 -- be changed, or for an IN OUT parameter, which can be changed but
11946 -- not to a null value. But for an OUT parameter, the initial value
11947 -- passed in can be null, so we can't set this flag in that case.
11949 if Ekind (Formal_Id) /= E_Out_Parameter then
11950 Set_Can_Never_Be_Null (Formal_Id);
11954 Set_Mechanism (Formal_Id, Default_Mechanism);
11955 Set_Formal_Validity (Formal_Id);
11956 end Set_Formal_Mode;
11958 -------------------------
11959 -- Set_Formal_Validity --
11960 -------------------------
11962 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11964 -- If no validity checking, then we cannot assume anything about the
11965 -- validity of parameters, since we do not know there is any checking
11966 -- of the validity on the call side.
11968 if not Validity_Checks_On then
11971 -- If validity checking for parameters is enabled, this means we are
11972 -- not supposed to make any assumptions about argument values.
11974 elsif Validity_Check_Parameters then
11977 -- If we are checking in parameters, we will assume that the caller is
11978 -- also checking parameters, so we can assume the parameter is valid.
11980 elsif Ekind (Formal_Id) = E_In_Parameter
11981 and then Validity_Check_In_Params
11983 Set_Is_Known_Valid (Formal_Id, True);
11985 -- Similar treatment for IN OUT parameters
11987 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11988 and then Validity_Check_In_Out_Params
11990 Set_Is_Known_Valid (Formal_Id, True);
11992 end Set_Formal_Validity;
11994 ------------------------
11995 -- Subtype_Conformant --
11996 ------------------------
11998 function Subtype_Conformant
11999 (New_Id : Entity_Id;
12000 Old_Id : Entity_Id;
12001 Skip_Controlling_Formals : Boolean := False) return Boolean
12005 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12006 Skip_Controlling_Formals => Skip_Controlling_Formals);
12008 end Subtype_Conformant;
12010 ---------------------
12011 -- Type_Conformant --
12012 ---------------------
12014 function Type_Conformant
12015 (New_Id : Entity_Id;
12016 Old_Id : Entity_Id;
12017 Skip_Controlling_Formals : Boolean := False) return Boolean
12021 May_Hide_Profile := False;
12023 (New_Id, Old_Id, Type_Conformant, False, Result,
12024 Skip_Controlling_Formals => Skip_Controlling_Formals);
12026 end Type_Conformant;
12028 -------------------------------
12029 -- Valid_Operator_Definition --
12030 -------------------------------
12032 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12035 Id : constant Name_Id := Chars (Designator);
12039 F := First_Formal (Designator);
12040 while Present (F) loop
12043 if Present (Default_Value (F)) then
12045 ("default values not allowed for operator parameters",
12048 -- For function instantiations that are operators, we must check
12049 -- separately that the corresponding generic only has in-parameters.
12050 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12051 -- an error could not arise in earlier versions of the language.
12053 elsif Ekind (F) /= E_In_Parameter then
12054 Error_Msg_N ("operators can only have IN parameters", F);
12060 -- Verify that user-defined operators have proper number of arguments
12061 -- First case of operators which can only be unary
12063 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12066 -- Case of operators which can be unary or binary
12068 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12069 N_OK := (N in 1 .. 2);
12071 -- All other operators can only be binary
12079 ("incorrect number of arguments for operator", Designator);
12083 and then Base_Type (Etype (Designator)) = Standard_Boolean
12084 and then not Is_Intrinsic_Subprogram (Designator)
12087 ("explicit definition of inequality not allowed", Designator);
12089 end Valid_Operator_Definition;