1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2019, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id);
210 -- Preanalysis of default expressions of subprogram formals. N is the
211 -- expression to be analyzed and T is the expected type.
213 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
214 -- Formal_Id is an formal parameter entity. This procedure deals with
215 -- setting the proper validity status for this entity, which depends on
216 -- the kind of parameter and the validity checking mode.
218 ---------------------------------------------
219 -- Analyze_Abstract_Subprogram_Declaration --
220 ---------------------------------------------
222 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
223 Scop : constant Entity_Id := Current_Scope;
224 Subp_Id : constant Entity_Id :=
225 Analyze_Subprogram_Specification (Specification (N));
228 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
230 Generate_Definition (Subp_Id);
232 -- Set the SPARK mode from the current context (may be overwritten later
233 -- with explicit pragma).
235 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
236 Set_SPARK_Pragma_Inherited (Subp_Id);
238 -- Preserve relevant elaboration-related attributes of the context which
239 -- are no longer available or very expensive to recompute once analysis,
240 -- resolution, and expansion are over.
242 Mark_Elaboration_Attributes
247 Set_Is_Abstract_Subprogram (Subp_Id);
248 New_Overloaded_Entity (Subp_Id);
249 Check_Delayed_Subprogram (Subp_Id);
251 Set_Categorization_From_Scope (Subp_Id, Scop);
253 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
254 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
256 -- Issue a warning if the abstract subprogram is neither a dispatching
257 -- operation nor an operation that overrides an inherited subprogram or
258 -- predefined operator, since this most likely indicates a mistake.
260 elsif Warn_On_Redundant_Constructs
261 and then not Is_Dispatching_Operation (Subp_Id)
262 and then not Present (Overridden_Operation (Subp_Id))
263 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
264 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
267 ("abstract subprogram is not dispatching or overriding?r?", N);
270 Generate_Reference_To_Formals (Subp_Id);
271 Check_Eliminated (Subp_Id);
273 if Has_Aspects (N) then
274 Analyze_Aspect_Specifications (N, Subp_Id);
276 end Analyze_Abstract_Subprogram_Declaration;
278 ---------------------------------
279 -- Analyze_Expression_Function --
280 ---------------------------------
282 procedure Analyze_Expression_Function (N : Node_Id) is
283 Expr : constant Node_Id := Expression (N);
284 Loc : constant Source_Ptr := Sloc (N);
285 LocX : constant Source_Ptr := Sloc (Expr);
286 Spec : constant Node_Id := Specification (N);
296 Def_Id : Entity_Id := Empty;
298 -- If the expression is a completion, Prev is the entity whose
299 -- declaration is completed. Def_Id is needed to analyze the spec.
301 -- Start of processing for Analyze_Expression_Function
304 -- This is one of the occasions on which we transform the tree during
305 -- semantic analysis. If this is a completion, transform the expression
306 -- function into an equivalent subprogram body, and analyze it.
308 -- Expression functions are inlined unconditionally. The back-end will
309 -- determine whether this is possible.
311 Inline_Processing_Required := True;
313 -- Create a specification for the generated body. This must be done
314 -- prior to the analysis of the initial declaration.
316 New_Spec := Copy_Subprogram_Spec (Spec);
317 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
319 -- If there are previous overloadable entities with the same name,
320 -- check whether any of them is completed by the expression function.
321 -- In a generic context a formal subprogram has no completion.
324 and then Is_Overloadable (Prev)
325 and then not Is_Formal_Subprogram (Prev)
327 Def_Id := Analyze_Subprogram_Specification (Spec);
328 Prev := Find_Corresponding_Spec (N);
330 -- The previous entity may be an expression function as well, in
331 -- which case the redeclaration is illegal.
334 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
335 N_Expression_Function
337 Error_Msg_Sloc := Sloc (Prev);
338 Error_Msg_N ("& conflicts with declaration#", Def_Id);
343 Ret := Make_Simple_Return_Statement (LocX, Expr);
346 Make_Subprogram_Body (Loc,
347 Specification => New_Spec,
348 Declarations => Empty_List,
349 Handled_Statement_Sequence =>
350 Make_Handled_Sequence_Of_Statements (LocX,
351 Statements => New_List (Ret)));
352 Set_Was_Expression_Function (New_Body);
354 -- If the expression completes a generic subprogram, we must create a
355 -- separate node for the body, because at instantiation the original
356 -- node of the generic copy must be a generic subprogram body, and
357 -- cannot be a expression function. Otherwise we just rewrite the
358 -- expression with the non-generic body.
360 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
361 Insert_After (N, New_Body);
363 -- Propagate any aspects or pragmas that apply to the expression
364 -- function to the proper body when the expression function acts
367 if Has_Aspects (N) then
368 Move_Aspects (N, To => New_Body);
371 Relocate_Pragmas_To_Body (New_Body);
373 Rewrite (N, Make_Null_Statement (Loc));
374 Set_Has_Completion (Prev, False);
377 Set_Is_Inlined (Prev);
379 -- If the expression function is a completion, the previous declaration
380 -- must come from source. We know already that it appears in the current
381 -- scope. The entity itself may be internally created if within a body
385 and then Is_Overloadable (Prev)
386 and then not Is_Formal_Subprogram (Prev)
387 and then Comes_From_Source (Parent (Prev))
389 Set_Has_Completion (Prev, False);
390 Set_Is_Inlined (Prev);
392 -- AI12-0103: Expression functions that are a completion freeze their
393 -- expression but don't freeze anything else (unlike regular bodies).
395 -- Note that we cannot defer this freezing to the analysis of the
396 -- expression itself, because a freeze node might appear in a nested
397 -- scope, leading to an elaboration order issue in gigi.
398 -- As elsewhere, we do not emit freeze nodes within a generic unit.
400 if not Inside_A_Generic then
403 Typ => Etype (Def_Id),
408 -- For navigation purposes, indicate that the function is a body
410 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
411 Rewrite (N, New_Body);
413 -- Remove any existing aspects from the original node because the act
414 -- of rewriting causes the list to be shared between the two nodes.
416 Orig_N := Original_Node (N);
417 Remove_Aspects (Orig_N);
419 -- Propagate any pragmas that apply to expression function to the
420 -- proper body when the expression function acts as a completion.
421 -- Aspects are automatically transfered because of node rewriting.
423 Relocate_Pragmas_To_Body (N);
426 -- Once the aspects of the generated body have been analyzed, create
427 -- a copy for ASIS purposes and associate it with the original node.
429 if Has_Aspects (N) then
430 Set_Aspect_Specifications (Orig_N,
431 New_Copy_List_Tree (Aspect_Specifications (N)));
434 -- Prev is the previous entity with the same name, but it is can
435 -- be an unrelated spec that is not completed by the expression
436 -- function. In that case the relevant entity is the one in the body.
437 -- Not clear that the backend can inline it in this case ???
439 if Has_Completion (Prev) then
441 -- The formals of the expression function are body formals,
442 -- and do not appear in the ali file, which will only contain
443 -- references to the formals of the original subprogram spec.
450 F1 := First_Formal (Def_Id);
451 F2 := First_Formal (Prev);
453 while Present (F1) loop
454 Set_Spec_Entity (F1, F2);
461 Set_Is_Inlined (Defining_Entity (New_Body));
464 -- If this is not a completion, create both a declaration and a body, so
465 -- that the expression can be inlined whenever possible.
468 -- An expression function that is not a completion is not a
469 -- subprogram declaration, and thus cannot appear in a protected
472 if Nkind (Parent (N)) = N_Protected_Definition then
474 ("an expression function is not a legal protected operation", N);
477 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
479 -- Remove any existing aspects from the original node because the act
480 -- of rewriting causes the list to be shared between the two nodes.
482 Orig_N := Original_Node (N);
483 Remove_Aspects (Orig_N);
487 -- Once the aspects of the generated spec have been analyzed, create
488 -- a copy for ASIS purposes and associate it with the original node.
490 if Has_Aspects (N) then
491 Set_Aspect_Specifications (Orig_N,
492 New_Copy_List_Tree (Aspect_Specifications (N)));
495 -- If aspect SPARK_Mode was specified on the body, it needs to be
496 -- repeated both on the generated spec and the body.
498 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
500 if Present (Asp) then
501 Asp := New_Copy_Tree (Asp);
502 Set_Analyzed (Asp, False);
503 Set_Aspect_Specifications (New_Body, New_List (Asp));
506 Def_Id := Defining_Entity (N);
507 Set_Is_Inlined (Def_Id);
509 -- Establish the linkages between the spec and the body. These are
510 -- used when the expression function acts as the prefix of attribute
511 -- 'Access in order to freeze the original expression which has been
512 -- moved to the generated body.
514 Set_Corresponding_Body (N, Defining_Entity (New_Body));
515 Set_Corresponding_Spec (New_Body, Def_Id);
517 -- Within a generic preanalyze the original expression for name
518 -- capture. The body is also generated but plays no role in
519 -- this because it is not part of the original source.
521 if Inside_A_Generic then
522 Set_Has_Completion (Def_Id);
524 Install_Formals (Def_Id);
525 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
529 -- To prevent premature freeze action, insert the new body at the end
530 -- of the current declarations, or at the end of the package spec.
531 -- However, resolve usage names now, to prevent spurious visibility
532 -- on later entities. Note that the function can now be called in
533 -- the current declarative part, which will appear to be prior to
534 -- the presence of the body in the code. There are nevertheless no
535 -- order of elaboration issues because all name resolution has taken
536 -- place at the point of declaration.
539 Decls : List_Id := List_Containing (N);
540 Expr : constant Node_Id := Expression (Ret);
541 Par : constant Node_Id := Parent (Decls);
542 Typ : constant Entity_Id := Etype (Def_Id);
545 -- If this is a wrapper created for in an instance for a formal
546 -- subprogram, insert body after declaration, to be analyzed when
547 -- the enclosing instance is analyzed.
550 and then Is_Generic_Actual_Subprogram (Def_Id)
552 Insert_After (N, New_Body);
555 if Nkind (Par) = N_Package_Specification
556 and then Decls = Visible_Declarations (Par)
557 and then Present (Private_Declarations (Par))
558 and then not Is_Empty_List (Private_Declarations (Par))
560 Decls := Private_Declarations (Par);
563 Insert_After (Last (Decls), New_Body);
565 -- Preanalyze the expression if not already done above
567 if not Inside_A_Generic then
569 Install_Formals (Def_Id);
570 Preanalyze_Formal_Expression (Expr, Typ);
571 Check_Limited_Return (Original_Node (N), Expr, Typ);
578 -- Check incorrect use of dynamically tagged expression. This doesn't
579 -- fall out automatically when analyzing the generated function body,
580 -- because Check_Dynamically_Tagged_Expression deliberately ignores
581 -- nodes that don't come from source.
584 and then Nkind (Def_Id) in N_Has_Etype
585 and then Is_Tagged_Type (Etype (Def_Id))
587 Check_Dynamically_Tagged_Expression
589 Typ => Etype (Def_Id),
590 Related_Nod => Original_Node (N));
593 -- We must enforce checks for unreferenced formals in our newly
594 -- generated function, so we propagate the referenced flag from the
595 -- original spec to the new spec as well as setting Comes_From_Source.
597 if Present (Parameter_Specifications (New_Spec)) then
599 Form_New_Def : Entity_Id;
600 Form_New_Spec : Entity_Id;
601 Form_Old_Def : Entity_Id;
602 Form_Old_Spec : Entity_Id;
605 Form_New_Spec := First (Parameter_Specifications (New_Spec));
606 Form_Old_Spec := First (Parameter_Specifications (Spec));
608 while Present (Form_New_Spec) and then Present (Form_Old_Spec) loop
609 Form_New_Def := Defining_Identifier (Form_New_Spec);
610 Form_Old_Def := Defining_Identifier (Form_Old_Spec);
612 Set_Comes_From_Source (Form_New_Def, True);
614 -- Because of the usefulness of unreferenced controlling
615 -- formals we exempt them from unreferenced warnings by marking
616 -- them as always referenced.
618 Set_Referenced (Form_Old_Def,
619 (Is_Formal (Form_Old_Def)
620 and then Is_Controlling_Formal (Form_Old_Def))
621 or else Referenced (Form_Old_Def));
623 Next (Form_New_Spec);
624 Next (Form_Old_Spec);
628 end Analyze_Expression_Function;
630 ----------------------------------------
631 -- Analyze_Extended_Return_Statement --
632 ----------------------------------------
634 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
636 Check_Compiler_Unit ("extended return statement", N);
637 Analyze_Return_Statement (N);
638 end Analyze_Extended_Return_Statement;
640 ----------------------------
641 -- Analyze_Function_Call --
642 ----------------------------
644 procedure Analyze_Function_Call (N : Node_Id) is
645 Actuals : constant List_Id := Parameter_Associations (N);
646 Func_Nam : constant Node_Id := Name (N);
652 -- A call of the form A.B (X) may be an Ada 2005 call, which is
653 -- rewritten as B (A, X). If the rewriting is successful, the call
654 -- has been analyzed and we just return.
656 if Nkind (Func_Nam) = N_Selected_Component
657 and then Name (N) /= Func_Nam
658 and then Is_Rewrite_Substitution (N)
659 and then Present (Etype (N))
664 -- If error analyzing name, then set Any_Type as result type and return
666 if Etype (Func_Nam) = Any_Type then
667 Set_Etype (N, Any_Type);
671 -- Otherwise analyze the parameters
673 if Present (Actuals) then
674 Actual := First (Actuals);
675 while Present (Actual) loop
677 Check_Parameterless_Call (Actual);
683 end Analyze_Function_Call;
685 -----------------------------
686 -- Analyze_Function_Return --
687 -----------------------------
689 procedure Analyze_Function_Return (N : Node_Id) is
690 Loc : constant Source_Ptr := Sloc (N);
691 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
692 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
694 R_Type : constant Entity_Id := Etype (Scope_Id);
695 -- Function result subtype
697 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
698 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
699 -- aggregate in a return statement.
701 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
702 -- Check that the return_subtype_indication properly matches the result
703 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
705 -----------------------------------
706 -- Check_Aggregate_Accessibility --
707 -----------------------------------
709 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
710 Typ : constant Entity_Id := Etype (Aggr);
717 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
718 Discr := First_Discriminant (Typ);
719 Assoc := First (Component_Associations (Aggr));
720 while Present (Discr) loop
721 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
722 Expr := Expression (Assoc);
724 if Nkind (Expr) = N_Attribute_Reference
725 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
727 Obj := Prefix (Expr);
728 while Nkind_In (Obj, N_Indexed_Component,
729 N_Selected_Component)
734 -- Do not check aliased formals or function calls. A
735 -- run-time check may still be needed ???
737 if Is_Entity_Name (Obj)
738 and then Comes_From_Source (Obj)
740 if Is_Formal (Entity (Obj))
741 and then Is_Aliased (Entity (Obj))
745 elsif Object_Access_Level (Obj) >
746 Scope_Depth (Scope (Scope_Id))
749 ("access discriminant in return aggregate would "
750 & "be a dangling reference", Obj);
756 Next_Discriminant (Discr);
759 end Check_Aggregate_Accessibility;
761 -------------------------------------
762 -- Check_Return_Subtype_Indication --
763 -------------------------------------
765 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
766 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
768 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
769 -- Subtype given in the extended return statement (must match R_Type)
771 Subtype_Ind : constant Node_Id :=
772 Object_Definition (Original_Node (Obj_Decl));
774 procedure Error_No_Match (N : Node_Id);
775 -- Output error messages for case where types do not statically
776 -- match. N is the location for the messages.
782 procedure Error_No_Match (N : Node_Id) is
785 ("subtype must statically match function result subtype", N);
787 if not Predicates_Match (R_Stm_Type, R_Type) then
788 Error_Msg_Node_2 := R_Type;
790 ("\predicate of& does not match predicate of&",
795 -- Start of processing for Check_Return_Subtype_Indication
798 -- First, avoid cascaded errors
800 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
804 -- "return access T" case; check that the return statement also has
805 -- "access T", and that the subtypes statically match:
806 -- if this is an access to subprogram the signatures must match.
808 if Is_Anonymous_Access_Type (R_Type) then
809 if Is_Anonymous_Access_Type (R_Stm_Type) then
810 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
812 if Base_Type (Designated_Type (R_Stm_Type)) /=
813 Base_Type (Designated_Type (R_Type))
814 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
816 Error_No_Match (Subtype_Mark (Subtype_Ind));
820 -- For two anonymous access to subprogram types, the types
821 -- themselves must be type conformant.
823 if not Conforming_Types
824 (R_Stm_Type, R_Type, Fully_Conformant)
826 Error_No_Match (Subtype_Ind);
831 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
834 -- If the return object is of an anonymous access type, then report
835 -- an error if the function's result type is not also anonymous.
837 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
838 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
840 ("anonymous access not allowed for function with named access "
841 & "result", Subtype_Ind);
843 -- Subtype indication case: check that the return object's type is
844 -- covered by the result type, and that the subtypes statically match
845 -- when the result subtype is constrained. Also handle record types
846 -- with unknown discriminants for which we have built the underlying
847 -- record view. Coverage is needed to allow specific-type return
848 -- objects when the result type is class-wide (see AI05-32).
850 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
851 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
855 Underlying_Record_View (Base_Type (R_Stm_Type))))
857 -- A null exclusion may be present on the return type, on the
858 -- function specification, on the object declaration or on the
861 if Is_Access_Type (R_Type)
863 (Can_Never_Be_Null (R_Type)
864 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
865 Can_Never_Be_Null (R_Stm_Type)
867 Error_No_Match (Subtype_Ind);
870 -- AI05-103: for elementary types, subtypes must statically match
872 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
873 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
874 Error_No_Match (Subtype_Ind);
878 -- All remaining cases are illegal
880 -- Note: previous versions of this subprogram allowed the return
881 -- value to be the ancestor of the return type if the return type
882 -- was a null extension. This was plainly incorrect.
886 ("wrong type for return_subtype_indication", Subtype_Ind);
888 end Check_Return_Subtype_Indication;
890 ---------------------
891 -- Local Variables --
892 ---------------------
895 Obj_Decl : Node_Id := Empty;
897 -- Start of processing for Analyze_Function_Return
900 Set_Return_Present (Scope_Id);
902 if Nkind (N) = N_Simple_Return_Statement then
903 Expr := Expression (N);
905 -- Guard against a malformed expression. The parser may have tried to
906 -- recover but the node is not analyzable.
908 if Nkind (Expr) = N_Error then
909 Set_Etype (Expr, Any_Type);
910 Expander_Mode_Save_And_Set (False);
914 -- The resolution of a controlled [extension] aggregate associated
915 -- with a return statement creates a temporary which needs to be
916 -- finalized on function exit. Wrap the return statement inside a
917 -- block so that the finalization machinery can detect this case.
918 -- This early expansion is done only when the return statement is
919 -- not part of a handled sequence of statements.
921 if Nkind_In (Expr, N_Aggregate,
922 N_Extension_Aggregate)
923 and then Needs_Finalization (R_Type)
924 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
927 Make_Block_Statement (Loc,
928 Handled_Statement_Sequence =>
929 Make_Handled_Sequence_Of_Statements (Loc,
930 Statements => New_List (Relocate_Node (N)))));
938 -- Ada 2005 (AI-251): If the type of the returned object is
939 -- an access to an interface type then we add an implicit type
940 -- conversion to force the displacement of the "this" pointer to
941 -- reference the secondary dispatch table. We cannot delay the
942 -- generation of this implicit conversion until the expansion
943 -- because in this case the type resolution changes the decoration
944 -- of the expression node to match R_Type; by contrast, if the
945 -- returned object is a class-wide interface type then it is too
946 -- early to generate here the implicit conversion since the return
947 -- statement may be rewritten by the expander into an extended
948 -- return statement whose expansion takes care of adding the
949 -- implicit type conversion to displace the pointer to the object.
952 and then Serious_Errors_Detected = 0
953 and then Is_Access_Type (R_Type)
954 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
955 and then Is_Interface (Designated_Type (R_Type))
956 and then Is_Progenitor (Designated_Type (R_Type),
957 Designated_Type (Etype (Expr)))
959 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
963 Resolve (Expr, R_Type);
964 Check_Limited_Return (N, Expr, R_Type);
966 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
967 Check_Aggregate_Accessibility (Expr);
971 -- RETURN only allowed in SPARK as the last statement in function
973 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
975 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
976 or else Present (Next (N)))
978 Check_SPARK_05_Restriction
979 ("RETURN should be the last statement in function", N);
983 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
984 Obj_Decl := Last (Return_Object_Declarations (N));
986 -- Analyze parts specific to extended_return_statement:
989 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
990 HSS : constant Node_Id := Handled_Statement_Sequence (N);
993 Expr := Expression (Obj_Decl);
995 -- Note: The check for OK_For_Limited_Init will happen in
996 -- Analyze_Object_Declaration; we treat it as a normal
997 -- object declaration.
999 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1002 Check_Return_Subtype_Indication (Obj_Decl);
1004 if Present (HSS) then
1007 if Present (Exception_Handlers (HSS)) then
1009 -- ???Has_Nested_Block_With_Handler needs to be set.
1010 -- Probably by creating an actual N_Block_Statement.
1011 -- Probably in Expand.
1017 -- Mark the return object as referenced, since the return is an
1018 -- implicit reference of the object.
1020 Set_Referenced (Defining_Identifier (Obj_Decl));
1022 Check_References (Stm_Entity);
1024 -- Check RM 6.5 (5.9/3)
1027 if Ada_Version < Ada_2012 then
1029 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1030 -- Can it really happen (extended return???)
1033 ("aliased only allowed for limited return objects "
1034 & "in Ada 2012??", N);
1036 elsif not Is_Limited_View (R_Type) then
1038 ("aliased only allowed for limited return objects", N);
1044 -- Case of Expr present
1046 if Present (Expr) then
1048 -- Defend against previous errors
1050 if Nkind (Expr) = N_Empty
1051 or else No (Etype (Expr))
1056 -- Apply constraint check. Note that this is done before the implicit
1057 -- conversion of the expression done for anonymous access types to
1058 -- ensure correct generation of the null-excluding check associated
1059 -- with null-excluding expressions found in return statements.
1061 Apply_Constraint_Check (Expr, R_Type);
1063 -- The return value is converted to the return type of the function,
1064 -- which implies a predicate check if the return type is predicated.
1065 -- We do not apply the check to a case expression because it will
1066 -- be expanded into a series of return statements, each of which
1067 -- will receive a predicate check.
1069 if Nkind (Expr) /= N_Case_Expression then
1070 Apply_Predicate_Check (Expr, R_Type);
1073 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1074 -- type, apply an implicit conversion of the expression to that type
1075 -- to force appropriate static and run-time accessibility checks.
1077 if Ada_Version >= Ada_2005
1078 and then Ekind (R_Type) = E_Anonymous_Access_Type
1080 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1081 Analyze_And_Resolve (Expr, R_Type);
1083 -- If this is a local anonymous access to subprogram, the
1084 -- accessibility check can be applied statically. The return is
1085 -- illegal if the access type of the return expression is declared
1086 -- inside of the subprogram (except if it is the subtype indication
1087 -- of an extended return statement).
1089 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1090 if not Comes_From_Source (Current_Scope)
1091 or else Ekind (Current_Scope) = E_Return_Statement
1096 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1098 Error_Msg_N ("cannot return local access to subprogram", N);
1101 -- The expression cannot be of a formal incomplete type
1103 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1104 and then Is_Generic_Type (Etype (Expr))
1107 ("cannot return expression of a formal incomplete type", N);
1110 -- If the result type is class-wide, then check that the return
1111 -- expression's type is not declared at a deeper level than the
1112 -- function (RM05-6.5(5.6/2)).
1114 if Ada_Version >= Ada_2005
1115 and then Is_Class_Wide_Type (R_Type)
1117 if Type_Access_Level (Etype (Expr)) >
1118 Subprogram_Access_Level (Scope_Id)
1121 ("level of return expression type is deeper than "
1122 & "class-wide function!", Expr);
1126 -- Check incorrect use of dynamically tagged expression
1128 if Is_Tagged_Type (R_Type) then
1129 Check_Dynamically_Tagged_Expression
1135 -- ??? A real run-time accessibility check is needed in cases
1136 -- involving dereferences of access parameters. For now we just
1137 -- check the static cases.
1139 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1140 and then Is_Limited_View (Etype (Scope_Id))
1141 and then Object_Access_Level (Expr) >
1142 Subprogram_Access_Level (Scope_Id)
1144 -- Suppress the message in a generic, where the rewriting
1147 if Inside_A_Generic then
1152 Make_Raise_Program_Error (Loc,
1153 Reason => PE_Accessibility_Check_Failed));
1156 Error_Msg_Warn := SPARK_Mode /= On;
1157 Error_Msg_N ("cannot return a local value by reference<<", N);
1158 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1162 if Known_Null (Expr)
1163 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1164 and then Null_Exclusion_Present (Parent (Scope_Id))
1166 Apply_Compile_Time_Constraint_Error
1168 Msg => "(Ada 2005) null not allowed for "
1169 & "null-excluding return??",
1170 Reason => CE_Null_Not_Allowed);
1173 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1174 -- has no initializing expression.
1176 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1177 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1178 Subprogram_Access_Level (Scope_Id)
1181 ("level of return expression type is deeper than "
1182 & "class-wide function!", Obj_Decl);
1185 end Analyze_Function_Return;
1187 -------------------------------------
1188 -- Analyze_Generic_Subprogram_Body --
1189 -------------------------------------
1191 procedure Analyze_Generic_Subprogram_Body
1195 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1196 Kind : constant Entity_Kind := Ekind (Gen_Id);
1197 Body_Id : Entity_Id;
1202 -- Copy body and disable expansion while analyzing the generic For a
1203 -- stub, do not copy the stub (which would load the proper body), this
1204 -- will be done when the proper body is analyzed.
1206 if Nkind (N) /= N_Subprogram_Body_Stub then
1207 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1210 -- Once the contents of the generic copy and the template are
1211 -- swapped, do the same for their respective aspect specifications.
1213 Exchange_Aspects (N, New_N);
1215 -- Collect all contract-related source pragmas found within the
1216 -- template and attach them to the contract of the subprogram body.
1217 -- This contract is used in the capture of global references within
1220 Create_Generic_Contract (N);
1225 Spec := Specification (N);
1227 -- Within the body of the generic, the subprogram is callable, and
1228 -- behaves like the corresponding non-generic unit.
1230 Body_Id := Defining_Entity (Spec);
1232 if Kind = E_Generic_Procedure
1233 and then Nkind (Spec) /= N_Procedure_Specification
1235 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1238 elsif Kind = E_Generic_Function
1239 and then Nkind (Spec) /= N_Function_Specification
1241 Error_Msg_N ("invalid body for generic function ", Body_Id);
1245 Set_Corresponding_Body (Gen_Decl, Body_Id);
1247 if Has_Completion (Gen_Id)
1248 and then Nkind (Parent (N)) /= N_Subunit
1250 Error_Msg_N ("duplicate generic body", N);
1253 Set_Has_Completion (Gen_Id);
1256 if Nkind (N) = N_Subprogram_Body_Stub then
1257 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1259 Set_Corresponding_Spec (N, Gen_Id);
1262 if Nkind (Parent (N)) = N_Compilation_Unit then
1263 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1266 -- Make generic parameters immediately visible in the body. They are
1267 -- needed to process the formals declarations. Then make the formals
1268 -- visible in a separate step.
1270 Push_Scope (Gen_Id);
1274 First_Ent : Entity_Id;
1277 First_Ent := First_Entity (Gen_Id);
1280 while Present (E) and then not Is_Formal (E) loop
1285 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1287 -- Now generic formals are visible, and the specification can be
1288 -- analyzed, for subsequent conformance check.
1290 Body_Id := Analyze_Subprogram_Specification (Spec);
1292 -- Make formal parameters visible
1296 -- E is the first formal parameter, we loop through the formals
1297 -- installing them so that they will be visible.
1299 Set_First_Entity (Gen_Id, E);
1300 while Present (E) loop
1306 -- Visible generic entity is callable within its own body
1308 Set_Ekind (Gen_Id, Ekind (Body_Id));
1309 Set_Ekind (Body_Id, E_Subprogram_Body);
1310 Set_Convention (Body_Id, Convention (Gen_Id));
1311 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1312 Set_Scope (Body_Id, Scope (Gen_Id));
1314 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1316 if Nkind (N) = N_Subprogram_Body_Stub then
1318 -- No body to analyze, so restore state of generic unit
1320 Set_Ekind (Gen_Id, Kind);
1321 Set_Ekind (Body_Id, Kind);
1323 if Present (First_Ent) then
1324 Set_First_Entity (Gen_Id, First_Ent);
1331 -- If this is a compilation unit, it must be made visible explicitly,
1332 -- because the compilation of the declaration, unlike other library
1333 -- unit declarations, does not. If it is not a unit, the following
1334 -- is redundant but harmless.
1336 Set_Is_Immediately_Visible (Gen_Id);
1337 Reference_Body_Formals (Gen_Id, Body_Id);
1339 if Is_Child_Unit (Gen_Id) then
1340 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1343 Set_Actual_Subtypes (N, Current_Scope);
1345 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1346 Set_SPARK_Pragma_Inherited (Body_Id);
1348 -- Analyze any aspect specifications that appear on the generic
1351 if Has_Aspects (N) then
1352 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1355 Analyze_Declarations (Declarations (N));
1358 -- Process the contract of the subprogram body after all declarations
1359 -- have been analyzed. This ensures that any contract-related pragmas
1360 -- are available through the N_Contract node of the body.
1362 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1364 Analyze (Handled_Statement_Sequence (N));
1365 Save_Global_References (Original_Node (N));
1367 -- Prior to exiting the scope, include generic formals again (if any
1368 -- are present) in the set of local entities.
1370 if Present (First_Ent) then
1371 Set_First_Entity (Gen_Id, First_Ent);
1374 Check_References (Gen_Id);
1377 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1378 Update_Use_Clause_Chain;
1379 Validate_Categorization_Dependency (N, Gen_Id);
1381 Check_Subprogram_Order (N);
1383 -- Outside of its body, unit is generic again
1385 Set_Ekind (Gen_Id, Kind);
1386 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1389 Style.Check_Identifier (Body_Id, Gen_Id);
1393 end Analyze_Generic_Subprogram_Body;
1395 ----------------------------
1396 -- Analyze_Null_Procedure --
1397 ----------------------------
1399 -- WARNING: This routine manages Ghost regions. Return statements must be
1400 -- replaced by gotos that jump to the end of the routine and restore the
1403 procedure Analyze_Null_Procedure
1405 Is_Completion : out Boolean)
1407 Loc : constant Source_Ptr := Sloc (N);
1408 Spec : constant Node_Id := Specification (N);
1410 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1411 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1412 Saved_ISMP : constant Boolean :=
1413 Ignore_SPARK_Mode_Pragmas_In_Instance;
1414 -- Save the Ghost and SPARK mode-related data to restore on exit
1416 Designator : Entity_Id;
1418 Null_Body : Node_Id := Empty;
1419 Null_Stmt : Node_Id := Null_Statement (Spec);
1423 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1425 -- A null procedure is Ghost when it is stand-alone and is subject to
1426 -- pragma Ghost, or when the corresponding spec is Ghost. Set the mode
1427 -- now, to ensure that any nodes generated during analysis and expansion
1428 -- are properly marked as Ghost.
1430 if Present (Prev) then
1431 Mark_And_Set_Ghost_Body (N, Prev);
1434 -- Capture the profile of the null procedure before analysis, for
1435 -- expansion at the freeze point and at each point of call. The body is
1436 -- used if the procedure has preconditions, or if it is a completion. In
1437 -- the first case the body is analyzed at the freeze point, in the other
1438 -- it replaces the null procedure declaration.
1440 -- For a null procedure that comes from source, a NULL statement is
1441 -- provided by the parser, which carries the source location of the
1442 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1443 -- from expansion, create one now.
1445 if No (Null_Stmt) then
1446 Null_Stmt := Make_Null_Statement (Loc);
1450 Make_Subprogram_Body (Loc,
1451 Specification => New_Copy_Tree (Spec),
1452 Declarations => New_List,
1453 Handled_Statement_Sequence =>
1454 Make_Handled_Sequence_Of_Statements (Loc,
1455 Statements => New_List (Null_Stmt)));
1457 -- Create new entities for body and formals
1459 Set_Defining_Unit_Name (Specification (Null_Body),
1460 Make_Defining_Identifier
1461 (Sloc (Defining_Entity (N)),
1462 Chars (Defining_Entity (N))));
1464 Form := First (Parameter_Specifications (Specification (Null_Body)));
1465 while Present (Form) loop
1466 Set_Defining_Identifier (Form,
1467 Make_Defining_Identifier
1468 (Sloc (Defining_Identifier (Form)),
1469 Chars (Defining_Identifier (Form))));
1473 -- Determine whether the null procedure may be a completion of a generic
1474 -- suprogram, in which case we use the new null body as the completion
1475 -- and set minimal semantic information on the original declaration,
1476 -- which is rewritten as a null statement.
1478 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1479 Insert_Before (N, Null_Body);
1480 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1482 Rewrite (N, Make_Null_Statement (Loc));
1483 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1484 Is_Completion := True;
1489 -- Resolve the types of the formals now, because the freeze point may
1490 -- appear in a different context, e.g. an instantiation.
1492 Form := First (Parameter_Specifications (Specification (Null_Body)));
1493 while Present (Form) loop
1494 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1495 Find_Type (Parameter_Type (Form));
1497 elsif No (Access_To_Subprogram_Definition
1498 (Parameter_Type (Form)))
1500 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1502 -- The case of a null procedure with a formal that is an
1503 -- access-to-subprogram type, and that is used as an actual
1504 -- in an instantiation is left to the enthusiastic reader.
1514 -- If there are previous overloadable entities with the same name, check
1515 -- whether any of them is completed by the null procedure.
1517 if Present (Prev) and then Is_Overloadable (Prev) then
1518 Designator := Analyze_Subprogram_Specification (Spec);
1519 Prev := Find_Corresponding_Spec (N);
1522 if No (Prev) or else not Comes_From_Source (Prev) then
1523 Designator := Analyze_Subprogram_Specification (Spec);
1524 Set_Has_Completion (Designator);
1526 -- Signal to caller that this is a procedure declaration
1528 Is_Completion := False;
1530 -- Null procedures are always inlined, but generic formal subprograms
1531 -- which appear as such in the internal instance of formal packages,
1532 -- need no completion and are not marked Inline.
1535 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1537 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1538 Set_Body_To_Inline (N, Null_Body);
1539 Set_Is_Inlined (Designator);
1543 -- The null procedure is a completion. We unconditionally rewrite
1544 -- this as a null body (even if expansion is not active), because
1545 -- there are various error checks that are applied on this body
1546 -- when it is analyzed (e.g. correct aspect placement).
1548 if Has_Completion (Prev) then
1549 Error_Msg_Sloc := Sloc (Prev);
1550 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1553 Check_Previous_Null_Procedure (N, Prev);
1555 Is_Completion := True;
1556 Rewrite (N, Null_Body);
1561 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
1562 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1563 end Analyze_Null_Procedure;
1565 -----------------------------
1566 -- Analyze_Operator_Symbol --
1567 -----------------------------
1569 -- An operator symbol such as "+" or "and" may appear in context where the
1570 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1571 -- is just a string, as in (conjunction = "or"). In these cases the parser
1572 -- generates this node, and the semantics does the disambiguation. Other
1573 -- such case are actuals in an instantiation, the generic unit in an
1574 -- instantiation, and pragma arguments.
1576 procedure Analyze_Operator_Symbol (N : Node_Id) is
1577 Par : constant Node_Id := Parent (N);
1580 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1581 or else Nkind (Par) = N_Function_Instantiation
1582 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1583 or else (Nkind (Par) = N_Pragma_Argument_Association
1584 and then not Is_Pragma_String_Literal (Par))
1585 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1586 or else (Nkind (Par) = N_Attribute_Reference
1587 and then Attribute_Name (Par) /= Name_Value)
1589 Find_Direct_Name (N);
1592 Change_Operator_Symbol_To_String_Literal (N);
1595 end Analyze_Operator_Symbol;
1597 -----------------------------------
1598 -- Analyze_Parameter_Association --
1599 -----------------------------------
1601 procedure Analyze_Parameter_Association (N : Node_Id) is
1603 Analyze (Explicit_Actual_Parameter (N));
1604 end Analyze_Parameter_Association;
1606 ----------------------------
1607 -- Analyze_Procedure_Call --
1608 ----------------------------
1610 -- WARNING: This routine manages Ghost regions. Return statements must be
1611 -- replaced by gotos that jump to the end of the routine and restore the
1614 procedure Analyze_Procedure_Call (N : Node_Id) is
1615 procedure Analyze_Call_And_Resolve;
1616 -- Do Analyze and Resolve calls for procedure call. At the end, check
1617 -- for illegal order dependence.
1618 -- ??? where is the check for illegal order dependencies?
1620 ------------------------------
1621 -- Analyze_Call_And_Resolve --
1622 ------------------------------
1624 procedure Analyze_Call_And_Resolve is
1626 if Nkind (N) = N_Procedure_Call_Statement then
1628 Resolve (N, Standard_Void_Type);
1632 end Analyze_Call_And_Resolve;
1636 Actuals : constant List_Id := Parameter_Associations (N);
1637 Loc : constant Source_Ptr := Sloc (N);
1638 P : constant Node_Id := Name (N);
1640 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1641 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1642 -- Save the Ghost-related attributes to restore on exit
1647 -- Start of processing for Analyze_Procedure_Call
1650 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1651 -- a procedure call or an entry call. The prefix may denote an access
1652 -- to subprogram type, in which case an implicit dereference applies.
1653 -- If the prefix is an indexed component (without implicit dereference)
1654 -- then the construct denotes a call to a member of an entire family.
1655 -- If the prefix is a simple name, it may still denote a call to a
1656 -- parameterless member of an entry family. Resolution of these various
1657 -- interpretations is delicate.
1659 -- Do not analyze machine code statements to avoid rejecting them in
1662 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1663 Set_Etype (P, Standard_Void_Type);
1668 -- If this is a call of the form Obj.Op, the call may have been analyzed
1669 -- and possibly rewritten into a block, in which case we are done.
1671 if Analyzed (N) then
1674 -- If there is an error analyzing the name (which may have been
1675 -- rewritten if the original call was in prefix notation) then error
1676 -- has been emitted already, mark node and return.
1678 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1679 Set_Etype (N, Any_Type);
1683 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1684 -- Set the mode now to ensure that any nodes generated during analysis
1685 -- and expansion are properly marked as Ghost.
1687 Mark_And_Set_Ghost_Procedure_Call (N);
1689 -- Otherwise analyze the parameters
1691 if Present (Actuals) then
1692 Actual := First (Actuals);
1694 while Present (Actual) loop
1696 Check_Parameterless_Call (Actual);
1701 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1703 if Nkind (P) = N_Attribute_Reference
1704 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1706 Name_Elab_Subp_Body)
1708 if Present (Actuals) then
1710 ("no parameters allowed for this call", First (Actuals));
1714 Set_Etype (N, Standard_Void_Type);
1717 elsif Is_Entity_Name (P)
1718 and then Is_Record_Type (Etype (Entity (P)))
1719 and then Remote_AST_I_Dereference (P)
1723 elsif Is_Entity_Name (P)
1724 and then Ekind (Entity (P)) /= E_Entry_Family
1726 if Is_Access_Type (Etype (P))
1727 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1728 and then No (Actuals)
1729 and then Comes_From_Source (N)
1731 Error_Msg_N ("missing explicit dereference in call", N);
1734 Analyze_Call_And_Resolve;
1736 -- If the prefix is the simple name of an entry family, this is a
1737 -- parameterless call from within the task body itself.
1739 elsif Is_Entity_Name (P)
1740 and then Nkind (P) = N_Identifier
1741 and then Ekind (Entity (P)) = E_Entry_Family
1742 and then Present (Actuals)
1743 and then No (Next (First (Actuals)))
1745 -- Can be call to parameterless entry family. What appears to be the
1746 -- sole argument is in fact the entry index. Rewrite prefix of node
1747 -- accordingly. Source representation is unchanged by this
1751 Make_Indexed_Component (Loc,
1753 Make_Selected_Component (Loc,
1754 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1755 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1756 Expressions => Actuals);
1757 Set_Name (N, New_N);
1758 Set_Etype (New_N, Standard_Void_Type);
1759 Set_Parameter_Associations (N, No_List);
1760 Analyze_Call_And_Resolve;
1762 elsif Nkind (P) = N_Explicit_Dereference then
1763 if Ekind (Etype (P)) = E_Subprogram_Type then
1764 Analyze_Call_And_Resolve;
1766 Error_Msg_N ("expect access to procedure in call", P);
1769 -- The name can be a selected component or an indexed component that
1770 -- yields an access to subprogram. Such a prefix is legal if the call
1771 -- has parameter associations.
1773 elsif Is_Access_Type (Etype (P))
1774 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1776 if Present (Actuals) then
1777 Analyze_Call_And_Resolve;
1779 Error_Msg_N ("missing explicit dereference in call ", N);
1782 -- If not an access to subprogram, then the prefix must resolve to the
1783 -- name of an entry, entry family, or protected operation.
1785 -- For the case of a simple entry call, P is a selected component where
1786 -- the prefix is the task and the selector name is the entry. A call to
1787 -- a protected procedure will have the same syntax. If the protected
1788 -- object contains overloaded operations, the entity may appear as a
1789 -- function, the context will select the operation whose type is Void.
1791 elsif Nkind (P) = N_Selected_Component
1792 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1796 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1797 -- in prefix notation may still be missing its controlling argument,
1798 -- so perform the transformation now.
1800 if SPARK_Mode = On and then In_Inlined_Body then
1802 Subp : constant Entity_Id := Entity (Selector_Name (P));
1803 Typ : constant Entity_Id := Etype (Prefix (P));
1806 if Is_Tagged_Type (Typ)
1807 and then Present (First_Formal (Subp))
1808 and then (Etype (First_Formal (Subp)) = Typ
1810 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1811 and then Try_Object_Operation (P)
1816 Analyze_Call_And_Resolve;
1821 Analyze_Call_And_Resolve;
1824 elsif Nkind (P) = N_Selected_Component
1825 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1826 and then Present (Actuals)
1827 and then No (Next (First (Actuals)))
1829 -- Can be call to parameterless entry family. What appears to be the
1830 -- sole argument is in fact the entry index. Rewrite prefix of node
1831 -- accordingly. Source representation is unchanged by this
1835 Make_Indexed_Component (Loc,
1836 Prefix => New_Copy (P),
1837 Expressions => Actuals);
1838 Set_Name (N, New_N);
1839 Set_Etype (New_N, Standard_Void_Type);
1840 Set_Parameter_Associations (N, No_List);
1841 Analyze_Call_And_Resolve;
1843 -- For the case of a reference to an element of an entry family, P is
1844 -- an indexed component whose prefix is a selected component (task and
1845 -- entry family), and whose index is the entry family index.
1847 elsif Nkind (P) = N_Indexed_Component
1848 and then Nkind (Prefix (P)) = N_Selected_Component
1849 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1851 Analyze_Call_And_Resolve;
1853 -- If the prefix is the name of an entry family, it is a call from
1854 -- within the task body itself.
1856 elsif Nkind (P) = N_Indexed_Component
1857 and then Nkind (Prefix (P)) = N_Identifier
1858 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1861 Make_Selected_Component (Loc,
1863 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1864 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1865 Rewrite (Prefix (P), New_N);
1867 Analyze_Call_And_Resolve;
1869 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1870 -- procedure name, so the construct can only be a qualified expression.
1872 elsif Nkind (P) = N_Qualified_Expression
1873 and then Ada_Version >= Ada_2012
1875 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1878 -- Anything else is an error
1881 Error_Msg_N ("invalid procedure or entry call", N);
1885 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1886 end Analyze_Procedure_Call;
1888 ------------------------------
1889 -- Analyze_Return_Statement --
1890 ------------------------------
1892 procedure Analyze_Return_Statement (N : Node_Id) is
1893 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
1894 N_Simple_Return_Statement));
1896 Returns_Object : constant Boolean :=
1897 Nkind (N) = N_Extended_Return_Statement
1899 (Nkind (N) = N_Simple_Return_Statement
1900 and then Present (Expression (N)));
1901 -- True if we're returning something; that is, "return <expression>;"
1902 -- or "return Result : T [:= ...]". False for "return;". Used for error
1903 -- checking: If Returns_Object is True, N should apply to a function
1904 -- body; otherwise N should apply to a procedure body, entry body,
1905 -- accept statement, or extended return statement.
1907 function Find_What_It_Applies_To return Entity_Id;
1908 -- Find the entity representing the innermost enclosing body, accept
1909 -- statement, or extended return statement. If the result is a callable
1910 -- construct or extended return statement, then this will be the value
1911 -- of the Return_Applies_To attribute. Otherwise, the program is
1912 -- illegal. See RM-6.5(4/2).
1914 -----------------------------
1915 -- Find_What_It_Applies_To --
1916 -----------------------------
1918 function Find_What_It_Applies_To return Entity_Id is
1919 Result : Entity_Id := Empty;
1922 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1923 -- and postconditions.
1925 for J in reverse 0 .. Scope_Stack.Last loop
1926 Result := Scope_Stack.Table (J).Entity;
1927 exit when not Ekind_In (Result, E_Block, E_Loop)
1928 and then Chars (Result) /= Name_uPostconditions;
1931 pragma Assert (Present (Result));
1933 end Find_What_It_Applies_To;
1935 -- Local declarations
1937 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1938 Kind : constant Entity_Kind := Ekind (Scope_Id);
1939 Loc : constant Source_Ptr := Sloc (N);
1940 Stm_Entity : constant Entity_Id :=
1942 (E_Return_Statement, Current_Scope, Loc, 'R');
1944 -- Start of processing for Analyze_Return_Statement
1947 Set_Return_Statement_Entity (N, Stm_Entity);
1949 Set_Etype (Stm_Entity, Standard_Void_Type);
1950 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1952 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1953 -- (4/2): an inner return statement will apply to this extended return.
1955 if Nkind (N) = N_Extended_Return_Statement then
1956 Push_Scope (Stm_Entity);
1959 -- Check that pragma No_Return is obeyed. Don't complain about the
1960 -- implicitly-generated return that is placed at the end.
1962 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1963 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1966 -- Warn on any unassigned OUT parameters if in procedure
1968 if Ekind (Scope_Id) = E_Procedure then
1969 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1972 -- Check that functions return objects, and other things do not
1974 if Kind = E_Function or else Kind = E_Generic_Function then
1975 if not Returns_Object then
1976 Error_Msg_N ("missing expression in return from function", N);
1979 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1980 if Returns_Object then
1981 Error_Msg_N ("procedure cannot return value (use function)", N);
1984 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1985 if Returns_Object then
1986 if Is_Protected_Type (Scope (Scope_Id)) then
1987 Error_Msg_N ("entry body cannot return value", N);
1989 Error_Msg_N ("accept statement cannot return value", N);
1993 elsif Kind = E_Return_Statement then
1995 -- We are nested within another return statement, which must be an
1996 -- extended_return_statement.
1998 if Returns_Object then
1999 if Nkind (N) = N_Extended_Return_Statement then
2001 ("extended return statement cannot be nested (use `RETURN;`)",
2004 -- Case of a simple return statement with a value inside extended
2005 -- return statement.
2009 ("return nested in extended return statement cannot return "
2010 & "value (use `RETURN;`)", N);
2015 Error_Msg_N ("illegal context for return statement", N);
2018 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2019 Analyze_Function_Return (N);
2021 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2022 Set_Return_Present (Scope_Id);
2025 if Nkind (N) = N_Extended_Return_Statement then
2029 Kill_Current_Values (Last_Assignment_Only => True);
2030 Check_Unreachable_Code (N);
2032 Analyze_Dimension (N);
2033 end Analyze_Return_Statement;
2035 -------------------------------------
2036 -- Analyze_Simple_Return_Statement --
2037 -------------------------------------
2039 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2041 if Present (Expression (N)) then
2042 Mark_Coextensions (N, Expression (N));
2045 Analyze_Return_Statement (N);
2046 end Analyze_Simple_Return_Statement;
2048 -------------------------
2049 -- Analyze_Return_Type --
2050 -------------------------
2052 procedure Analyze_Return_Type (N : Node_Id) is
2053 Designator : constant Entity_Id := Defining_Entity (N);
2054 Typ : Entity_Id := Empty;
2057 -- Normal case where result definition does not indicate an error
2059 if Result_Definition (N) /= Error then
2060 if Nkind (Result_Definition (N)) = N_Access_Definition then
2061 Check_SPARK_05_Restriction
2062 ("access result is not allowed", Result_Definition (N));
2064 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2067 AD : constant Node_Id :=
2068 Access_To_Subprogram_Definition (Result_Definition (N));
2070 if Present (AD) and then Protected_Present (AD) then
2071 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2073 Typ := Access_Definition (N, Result_Definition (N));
2077 Set_Parent (Typ, Result_Definition (N));
2078 Set_Is_Local_Anonymous_Access (Typ);
2079 Set_Etype (Designator, Typ);
2081 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2083 Null_Exclusion_Static_Checks (N);
2085 -- Subtype_Mark case
2088 Find_Type (Result_Definition (N));
2089 Typ := Entity (Result_Definition (N));
2090 Set_Etype (Designator, Typ);
2092 -- Unconstrained array as result is not allowed in SPARK
2094 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2095 Check_SPARK_05_Restriction
2096 ("returning an unconstrained array is not allowed",
2097 Result_Definition (N));
2100 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2102 Null_Exclusion_Static_Checks (N);
2104 -- If a null exclusion is imposed on the result type, then create
2105 -- a null-excluding itype (an access subtype) and use it as the
2106 -- function's Etype. Note that the null exclusion checks are done
2107 -- right before this, because they don't get applied to types that
2108 -- do not come from source.
2110 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2111 Set_Etype (Designator,
2112 Create_Null_Excluding_Itype
2115 Scope_Id => Scope (Current_Scope)));
2117 -- The new subtype must be elaborated before use because
2118 -- it is visible outside of the function. However its base
2119 -- type may not be frozen yet, so the reference that will
2120 -- force elaboration must be attached to the freezing of
2123 -- If the return specification appears on a proper body,
2124 -- the subtype will have been created already on the spec.
2126 if Is_Frozen (Typ) then
2127 if Nkind (Parent (N)) = N_Subprogram_Body
2128 and then Nkind (Parent (Parent (N))) = N_Subunit
2132 Build_Itype_Reference (Etype (Designator), Parent (N));
2136 Ensure_Freeze_Node (Typ);
2139 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2141 Set_Itype (IR, Etype (Designator));
2142 Append_Freeze_Actions (Typ, New_List (IR));
2147 Set_Etype (Designator, Typ);
2150 if Ekind (Typ) = E_Incomplete_Type
2151 or else (Is_Class_Wide_Type (Typ)
2152 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2154 -- AI05-0151: Tagged incomplete types are allowed in all formal
2155 -- parts. Untagged incomplete types are not allowed in bodies.
2156 -- As a consequence, limited views cannot appear in a basic
2157 -- declaration that is itself within a body, because there is
2158 -- no point at which the non-limited view will become visible.
2160 if Ada_Version >= Ada_2012 then
2161 if From_Limited_With (Typ) and then In_Package_Body then
2163 ("invalid use of incomplete type&",
2164 Result_Definition (N), Typ);
2166 -- The return type of a subprogram body cannot be of a
2167 -- formal incomplete type.
2169 elsif Is_Generic_Type (Typ)
2170 and then Nkind (Parent (N)) = N_Subprogram_Body
2173 ("return type cannot be a formal incomplete type",
2174 Result_Definition (N));
2176 elsif Is_Class_Wide_Type (Typ)
2177 and then Is_Generic_Type (Root_Type (Typ))
2178 and then Nkind (Parent (N)) = N_Subprogram_Body
2181 ("return type cannot be a formal incomplete type",
2182 Result_Definition (N));
2184 elsif Is_Tagged_Type (Typ) then
2187 -- Use is legal in a thunk generated for an operation
2188 -- inherited from a progenitor.
2190 elsif Is_Thunk (Designator)
2191 and then Present (Non_Limited_View (Typ))
2195 elsif Nkind (Parent (N)) = N_Subprogram_Body
2196 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2200 ("invalid use of untagged incomplete type&",
2204 -- The type must be completed in the current package. This
2205 -- is checked at the end of the package declaration when
2206 -- Taft-amendment types are identified. If the return type
2207 -- is class-wide, there is no required check, the type can
2208 -- be a bona fide TAT.
2210 if Ekind (Scope (Current_Scope)) = E_Package
2211 and then In_Private_Part (Scope (Current_Scope))
2212 and then not Is_Class_Wide_Type (Typ)
2214 Append_Elmt (Designator, Private_Dependents (Typ));
2219 ("invalid use of incomplete type&", Designator, Typ);
2224 -- Case where result definition does indicate an error
2227 Set_Etype (Designator, Any_Type);
2229 end Analyze_Return_Type;
2231 -----------------------------
2232 -- Analyze_Subprogram_Body --
2233 -----------------------------
2235 procedure Analyze_Subprogram_Body (N : Node_Id) is
2236 Loc : constant Source_Ptr := Sloc (N);
2237 Body_Spec : constant Node_Id := Specification (N);
2238 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2241 if Debug_Flag_C then
2242 Write_Str ("==> subprogram body ");
2243 Write_Name (Chars (Body_Id));
2244 Write_Str (" from ");
2245 Write_Location (Loc);
2250 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2252 -- The real work is split out into the helper, so it can do "return;"
2253 -- without skipping the debug output:
2255 Analyze_Subprogram_Body_Helper (N);
2257 if Debug_Flag_C then
2259 Write_Str ("<== subprogram body ");
2260 Write_Name (Chars (Body_Id));
2261 Write_Str (" from ");
2262 Write_Location (Loc);
2265 end Analyze_Subprogram_Body;
2267 ------------------------------------
2268 -- Analyze_Subprogram_Body_Helper --
2269 ------------------------------------
2271 -- This procedure is called for regular subprogram bodies, generic bodies,
2272 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2273 -- specification matters, and is used to create a proper declaration for
2274 -- the subprogram, or to perform conformance checks.
2276 -- WARNING: This routine manages Ghost regions. Return statements must be
2277 -- replaced by gotos that jump to the end of the routine and restore the
2280 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2281 Body_Spec : Node_Id := Specification (N);
2282 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2283 Loc : constant Source_Ptr := Sloc (N);
2284 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2286 Conformant : Boolean;
2287 Desig_View : Entity_Id := Empty;
2288 Exch_Views : Elist_Id := No_Elist;
2290 Mask_Types : Elist_Id := No_Elist;
2291 Prot_Typ : Entity_Id := Empty;
2292 Spec_Decl : Node_Id := Empty;
2293 Spec_Id : Entity_Id;
2295 Last_Real_Spec_Entity : Entity_Id := Empty;
2296 -- When we analyze a separate spec, the entity chain ends up containing
2297 -- the formals, as well as any itypes generated during analysis of the
2298 -- default expressions for parameters, or the arguments of associated
2299 -- precondition/postcondition pragmas (which are analyzed in the context
2300 -- of the spec since they have visibility on formals).
2302 -- These entities belong with the spec and not the body. However we do
2303 -- the analysis of the body in the context of the spec (again to obtain
2304 -- visibility to the formals), and all the entities generated during
2305 -- this analysis end up also chained to the entity chain of the spec.
2306 -- But they really belong to the body, and there is circuitry to move
2307 -- them from the spec to the body.
2309 -- However, when we do this move, we don't want to move the real spec
2310 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2311 -- variable points to the last real spec entity, so we only move those
2312 -- chained beyond that point. It is initialized to Empty to deal with
2313 -- the case where there is no separate spec.
2315 function Body_Has_Contract return Boolean;
2316 -- Check whether unanalyzed body has an aspect or pragma that may
2317 -- generate a SPARK contract.
2319 function Body_Has_SPARK_Mode_On return Boolean;
2320 -- Check whether SPARK_Mode On applies to the subprogram body, either
2321 -- because it is specified directly on the body, or because it is
2322 -- inherited from the enclosing subprogram or package.
2324 procedure Build_Subprogram_Declaration;
2325 -- Create a matching subprogram declaration for subprogram body N
2327 procedure Check_Anonymous_Return;
2328 -- Ada 2005: if a function returns an access type that denotes a task,
2329 -- or a type that contains tasks, we must create a master entity for
2330 -- the anonymous type, which typically will be used in an allocator
2331 -- in the body of the function.
2333 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2334 -- Look ahead to recognize a pragma that may appear after the body.
2335 -- If there is a previous spec, check that it appears in the same
2336 -- declarative part. If the pragma is Inline_Always, perform inlining
2337 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2338 -- If the body acts as a spec, and inlining is required, we create a
2339 -- subprogram declaration for it, in order to attach the body to inline.
2340 -- If pragma does not appear after the body, check whether there is
2341 -- an inline pragma before any local declarations.
2343 procedure Check_Missing_Return;
2344 -- Checks for a function with a no return statements, and also performs
2345 -- the warning checks implemented by Check_Returns. In formal mode, also
2346 -- verify that a function ends with a RETURN and that a procedure does
2347 -- not contain any RETURN.
2349 function Disambiguate_Spec return Entity_Id;
2350 -- When a primitive is declared between the private view and the full
2351 -- view of a concurrent type which implements an interface, a special
2352 -- mechanism is used to find the corresponding spec of the primitive
2355 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2356 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2357 -- incomplete types coming from a limited context and replace their
2358 -- limited views with the non-limited ones. Return the list of changes
2359 -- to be used to undo the transformation.
2361 function Is_Private_Concurrent_Primitive
2362 (Subp_Id : Entity_Id) return Boolean;
2363 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2364 -- type that implements an interface and has a private view.
2366 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2367 -- N is the body generated for an expression function that is not a
2368 -- completion and Spec_Id the defining entity of its spec. Mark all
2369 -- the not-yet-frozen types referenced by the simple return statement
2370 -- of the function as formally frozen.
2372 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2373 -- Undo the transformation done by Exchange_Limited_Views.
2375 procedure Set_Trivial_Subprogram (N : Node_Id);
2376 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2377 -- subprogram whose body is being analyzed. N is the statement node
2378 -- causing the flag to be set, if the following statement is a return
2379 -- of an entity, we mark the entity as set in source to suppress any
2380 -- warning on the stylized use of function stubs with a dummy return.
2382 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2383 -- Undo the transformation done by Mask_Unfrozen_Types
2385 procedure Verify_Overriding_Indicator;
2386 -- If there was a previous spec, the entity has been entered in the
2387 -- current scope previously. If the body itself carries an overriding
2388 -- indicator, check that it is consistent with the known status of the
2391 -----------------------
2392 -- Body_Has_Contract --
2393 -----------------------
2395 function Body_Has_Contract return Boolean is
2396 Decls : constant List_Id := Declarations (N);
2400 -- Check for aspects that may generate a contract
2402 if Present (Aspect_Specifications (N)) then
2403 Item := First (Aspect_Specifications (N));
2404 while Present (Item) loop
2405 if Is_Subprogram_Contract_Annotation (Item) then
2413 -- Check for pragmas that may generate a contract
2415 if Present (Decls) then
2416 Item := First (Decls);
2417 while Present (Item) loop
2418 if Nkind (Item) = N_Pragma
2419 and then Is_Subprogram_Contract_Annotation (Item)
2429 end Body_Has_Contract;
2431 ----------------------------
2432 -- Body_Has_SPARK_Mode_On --
2433 ----------------------------
2435 function Body_Has_SPARK_Mode_On return Boolean is
2436 Decls : constant List_Id := Declarations (N);
2440 -- Check for SPARK_Mode aspect
2442 if Present (Aspect_Specifications (N)) then
2443 Item := First (Aspect_Specifications (N));
2444 while Present (Item) loop
2445 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2446 return Get_SPARK_Mode_From_Annotation (Item) = On;
2453 -- Check for SPARK_Mode pragma
2455 if Present (Decls) then
2456 Item := First (Decls);
2457 while Present (Item) loop
2459 -- Pragmas that apply to a subprogram body are usually grouped
2460 -- together. Look for a potential pragma SPARK_Mode among them.
2462 if Nkind (Item) = N_Pragma then
2463 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2464 return Get_SPARK_Mode_From_Annotation (Item) = On;
2467 -- Otherwise the first non-pragma declarative item terminates
2468 -- the region where pragma SPARK_Mode may appear.
2478 -- Otherwise, the applicable SPARK_Mode is inherited from the
2479 -- enclosing subprogram or package.
2481 return SPARK_Mode = On;
2482 end Body_Has_SPARK_Mode_On;
2484 ----------------------------------
2485 -- Build_Subprogram_Declaration --
2486 ----------------------------------
2488 procedure Build_Subprogram_Declaration is
2489 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2490 -- Relocate certain categorization pragmas from the declarative list
2491 -- of subprogram body From and insert them after node To. The pragmas
2494 -- Volatile_Function
2495 -- Also copy pragma SPARK_Mode if present in the declarative list
2496 -- of subprogram body From and insert it after node To. This pragma
2497 -- should not be moved, as it applies to the body too.
2503 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2505 Next_Decl : Node_Id;
2508 pragma Assert (Nkind (From) = N_Subprogram_Body);
2510 -- The destination node must be part of a list, as the pragmas are
2511 -- inserted after it.
2513 pragma Assert (Is_List_Member (To));
2515 -- Inspect the declarations of the subprogram body looking for
2516 -- specific pragmas.
2518 Decl := First (Declarations (N));
2519 while Present (Decl) loop
2520 Next_Decl := Next (Decl);
2522 if Nkind (Decl) = N_Pragma then
2523 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2524 Insert_After (To, New_Copy_Tree (Decl));
2526 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2528 Name_Volatile_Function)
2531 Insert_After (To, Decl);
2542 Subp_Decl : Node_Id;
2544 -- Start of processing for Build_Subprogram_Declaration
2547 -- Create a matching subprogram spec using the profile of the body.
2548 -- The structure of the tree is identical, but has new entities for
2549 -- the defining unit name and formal parameters.
2552 Make_Subprogram_Declaration (Loc,
2553 Specification => Copy_Subprogram_Spec (Body_Spec));
2554 Set_Comes_From_Source (Subp_Decl, True);
2556 -- Also mark parameters as coming from source
2558 if Present (Parameter_Specifications (Specification (Subp_Decl))) then
2563 First (Parameter_Specifications (Specification (Subp_Decl)));
2565 while Present (Form) loop
2566 Set_Comes_From_Source (Defining_Identifier (Form), True);
2572 -- Relocate the aspects and relevant pragmas from the subprogram body
2573 -- to the generated spec because it acts as the initial declaration.
2575 Insert_Before (N, Subp_Decl);
2576 Move_Aspects (N, To => Subp_Decl);
2577 Move_Pragmas (N, To => Subp_Decl);
2579 -- Ensure that the generated corresponding spec and original body
2580 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2581 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2582 -- correctly set for local subprograms.
2584 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2586 Analyze (Subp_Decl);
2588 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2589 -- the body since the expander may generate calls using that entity.
2590 -- Required to ensure that Expand_Call rewrites calls to this
2591 -- function by calls to the built procedure.
2593 if Modify_Tree_For_C
2594 and then Nkind (Body_Spec) = N_Function_Specification
2596 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2598 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2599 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2600 Corresponding_Procedure
2601 (Defining_Entity (Specification (Subp_Decl))));
2604 -- Analyze any relocated source pragmas or pragmas created for aspect
2607 Decl := Next (Subp_Decl);
2608 while Present (Decl) loop
2610 -- Stop the search for pragmas once the body has been reached as
2611 -- this terminates the region where pragmas may appear.
2616 elsif Nkind (Decl) = N_Pragma then
2623 Spec_Id := Defining_Entity (Subp_Decl);
2624 Set_Corresponding_Spec (N, Spec_Id);
2626 -- Mark the generated spec as a source construct to ensure that all
2627 -- calls to it are properly registered in ALI files for GNATprove.
2629 Set_Comes_From_Source (Spec_Id, True);
2631 -- Ensure that the specs of the subprogram declaration and its body
2632 -- are identical, otherwise they will appear non-conformant due to
2633 -- rewritings in the default values of formal parameters.
2635 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2636 Set_Specification (N, Body_Spec);
2637 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2638 end Build_Subprogram_Declaration;
2640 ----------------------------
2641 -- Check_Anonymous_Return --
2642 ----------------------------
2644 procedure Check_Anonymous_Return is
2650 if Present (Spec_Id) then
2656 if Ekind (Scop) = E_Function
2657 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2658 and then not Is_Thunk (Scop)
2660 -- Skip internally built functions which handle the case of
2661 -- a null access (see Expand_Interface_Conversion)
2663 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2664 and then not Comes_From_Source (Parent (Scop)))
2666 and then (Has_Task (Designated_Type (Etype (Scop)))
2668 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2670 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2671 and then Expander_Active
2673 -- Avoid cases with no tasking support
2675 and then RTE_Available (RE_Current_Master)
2676 and then not Restriction_Active (No_Task_Hierarchy)
2679 Make_Object_Declaration (Loc,
2680 Defining_Identifier =>
2681 Make_Defining_Identifier (Loc, Name_uMaster),
2682 Constant_Present => True,
2683 Object_Definition =>
2684 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2686 Make_Explicit_Dereference (Loc,
2687 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2689 if Present (Declarations (N)) then
2690 Prepend (Decl, Declarations (N));
2692 Set_Declarations (N, New_List (Decl));
2695 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2696 Set_Has_Master_Entity (Scop);
2698 -- Now mark the containing scope as a task master
2701 while Nkind (Par) /= N_Compilation_Unit loop
2702 Par := Parent (Par);
2703 pragma Assert (Present (Par));
2705 -- If we fall off the top, we are at the outer level, and
2706 -- the environment task is our effective master, so nothing
2710 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2712 Set_Is_Task_Master (Par, True);
2717 end Check_Anonymous_Return;
2719 -------------------------
2720 -- Check_Inline_Pragma --
2721 -------------------------
2723 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2727 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2728 -- True when N is a pragma Inline or Inline_Always that applies
2729 -- to this subprogram.
2731 -----------------------
2732 -- Is_Inline_Pragma --
2733 -----------------------
2735 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2737 if Nkind (N) = N_Pragma
2739 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2740 or else (Pragma_Name_Unmapped (N) = Name_Inline
2742 (Front_End_Inlining or else Optimization_Level > 0)))
2743 and then Present (Pragma_Argument_Associations (N))
2746 Pragma_Arg : Node_Id :=
2747 Expression (First (Pragma_Argument_Associations (N)));
2749 if Nkind (Pragma_Arg) = N_Selected_Component then
2750 Pragma_Arg := Selector_Name (Pragma_Arg);
2753 return Chars (Pragma_Arg) = Chars (Body_Id);
2759 end Is_Inline_Pragma;
2761 -- Start of processing for Check_Inline_Pragma
2764 if not Expander_Active then
2768 if Is_List_Member (N)
2769 and then Present (Next (N))
2770 and then Is_Inline_Pragma (Next (N))
2774 elsif Nkind (N) /= N_Subprogram_Body_Stub
2775 and then Present (Declarations (N))
2776 and then Is_Inline_Pragma (First (Declarations (N)))
2778 Prag := First (Declarations (N));
2784 if Present (Prag) then
2785 if Present (Spec_Id) then
2786 if Is_List_Member (N)
2787 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2788 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2794 -- Create a subprogram declaration, to make treatment uniform.
2795 -- Make the sloc of the subprogram name that of the entity in
2796 -- the body, so that style checks find identical strings.
2799 Subp : constant Entity_Id :=
2800 Make_Defining_Identifier
2801 (Sloc (Body_Id), Chars (Body_Id));
2802 Decl : constant Node_Id :=
2803 Make_Subprogram_Declaration (Loc,
2805 New_Copy_Tree (Specification (N)));
2808 -- Link the body and the generated spec
2810 Set_Corresponding_Body (Decl, Body_Id);
2811 Set_Corresponding_Spec (N, Subp);
2813 Set_Defining_Unit_Name (Specification (Decl), Subp);
2815 -- To ensure proper coverage when body is inlined, indicate
2816 -- whether the subprogram comes from source.
2818 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2820 if Present (First_Formal (Body_Id)) then
2821 Plist := Copy_Parameter_List (Body_Id);
2822 Set_Parameter_Specifications
2823 (Specification (Decl), Plist);
2826 -- Move aspects to the new spec
2828 if Has_Aspects (N) then
2829 Move_Aspects (N, To => Decl);
2832 Insert_Before (N, Decl);
2835 Set_Has_Pragma_Inline (Subp);
2837 if Pragma_Name (Prag) = Name_Inline_Always then
2838 Set_Is_Inlined (Subp);
2839 Set_Has_Pragma_Inline_Always (Subp);
2842 -- Prior to copying the subprogram body to create a template
2843 -- for it for subsequent inlining, remove the pragma from
2844 -- the current body so that the copy that will produce the
2845 -- new body will start from a completely unanalyzed tree.
2847 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2848 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2855 end Check_Inline_Pragma;
2857 --------------------------
2858 -- Check_Missing_Return --
2859 --------------------------
2861 procedure Check_Missing_Return is
2863 Missing_Ret : Boolean;
2866 if Nkind (Body_Spec) = N_Function_Specification then
2867 if Present (Spec_Id) then
2873 if Return_Present (Id) then
2874 Check_Returns (HSS, 'F', Missing_Ret);
2877 Set_Has_Missing_Return (Id);
2880 -- Within a premature instantiation of a package with no body, we
2881 -- build completions of the functions therein, with a Raise
2882 -- statement. No point in complaining about a missing return in
2885 elsif Ekind (Id) = E_Function
2886 and then In_Instance
2887 and then Present (Statements (HSS))
2888 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2892 elsif Is_Generic_Subprogram (Id)
2893 or else not Is_Machine_Code_Subprogram (Id)
2895 Error_Msg_N ("missing RETURN statement in function body", N);
2898 -- If procedure with No_Return, check returns
2900 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2901 if Present (Spec_Id) then
2907 if No_Return (Id) then
2908 Check_Returns (HSS, 'P', Missing_Ret, Id);
2912 -- Special checks in SPARK mode
2914 if Nkind (Body_Spec) = N_Function_Specification then
2916 -- In SPARK mode, last statement of a function should be a return
2919 Stat : constant Node_Id := Last_Source_Statement (HSS);
2922 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2923 N_Extended_Return_Statement)
2925 Check_SPARK_05_Restriction
2926 ("last statement in function should be RETURN", Stat);
2930 -- In SPARK mode, verify that a procedure has no return
2932 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2933 if Present (Spec_Id) then
2939 -- Would be nice to point to return statement here, can we
2940 -- borrow the Check_Returns procedure here ???
2942 if Return_Present (Id) then
2943 Check_SPARK_05_Restriction
2944 ("procedure should not have RETURN", N);
2947 end Check_Missing_Return;
2949 -----------------------
2950 -- Disambiguate_Spec --
2951 -----------------------
2953 function Disambiguate_Spec return Entity_Id is
2954 Priv_Spec : Entity_Id;
2957 procedure Replace_Types (To_Corresponding : Boolean);
2958 -- Depending on the flag, replace the type of formal parameters of
2959 -- Body_Id if it is a concurrent type implementing interfaces with
2960 -- the corresponding record type or the other way around.
2962 procedure Replace_Types (To_Corresponding : Boolean) is
2964 Formal_Typ : Entity_Id;
2967 Formal := First_Formal (Body_Id);
2968 while Present (Formal) loop
2969 Formal_Typ := Etype (Formal);
2971 if Is_Class_Wide_Type (Formal_Typ) then
2972 Formal_Typ := Root_Type (Formal_Typ);
2975 -- From concurrent type to corresponding record
2977 if To_Corresponding then
2978 if Is_Concurrent_Type (Formal_Typ)
2979 and then Present (Corresponding_Record_Type (Formal_Typ))
2982 (Corresponding_Record_Type (Formal_Typ)))
2985 Corresponding_Record_Type (Formal_Typ));
2988 -- From corresponding record to concurrent type
2991 if Is_Concurrent_Record_Type (Formal_Typ)
2992 and then Present (Interfaces (Formal_Typ))
2995 Corresponding_Concurrent_Type (Formal_Typ));
2999 Next_Formal (Formal);
3003 -- Start of processing for Disambiguate_Spec
3006 -- Try to retrieve the specification of the body as is. All error
3007 -- messages are suppressed because the body may not have a spec in
3008 -- its current state.
3010 Spec_N := Find_Corresponding_Spec (N, False);
3012 -- It is possible that this is the body of a primitive declared
3013 -- between a private and a full view of a concurrent type. The
3014 -- controlling parameter of the spec carries the concurrent type,
3015 -- not the corresponding record type as transformed by Analyze_
3016 -- Subprogram_Specification. In such cases, we undo the change
3017 -- made by the analysis of the specification and try to find the
3020 -- Note that wrappers already have their corresponding specs and
3021 -- bodies set during their creation, so if the candidate spec is
3022 -- a wrapper, then we definitely need to swap all types to their
3023 -- original concurrent status.
3026 or else Is_Primitive_Wrapper (Spec_N)
3028 -- Restore all references of corresponding record types to the
3029 -- original concurrent types.
3031 Replace_Types (To_Corresponding => False);
3032 Priv_Spec := Find_Corresponding_Spec (N, False);
3034 -- The current body truly belongs to a primitive declared between
3035 -- a private and a full view. We leave the modified body as is,
3036 -- and return the true spec.
3038 if Present (Priv_Spec)
3039 and then Is_Private_Primitive (Priv_Spec)
3044 -- In case that this is some sort of error, restore the original
3045 -- state of the body.
3047 Replace_Types (To_Corresponding => True);
3051 end Disambiguate_Spec;
3053 ----------------------------
3054 -- Exchange_Limited_Views --
3055 ----------------------------
3057 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3058 Result : Elist_Id := No_Elist;
3060 procedure Detect_And_Exchange (Id : Entity_Id);
3061 -- Determine whether Id's type denotes an incomplete type associated
3062 -- with a limited with clause and exchange the limited view with the
3063 -- non-limited one when available. Note that the non-limited view
3064 -- may exist because of a with_clause in another unit in the context,
3065 -- but cannot be used because the current view of the enclosing unit
3066 -- is still a limited view.
3068 -------------------------
3069 -- Detect_And_Exchange --
3070 -------------------------
3072 procedure Detect_And_Exchange (Id : Entity_Id) is
3073 Typ : constant Entity_Id := Etype (Id);
3075 if From_Limited_With (Typ)
3076 and then Has_Non_Limited_View (Typ)
3077 and then not From_Limited_With (Scope (Typ))
3080 Result := New_Elmt_List;
3083 Prepend_Elmt (Typ, Result);
3084 Prepend_Elmt (Id, Result);
3085 Set_Etype (Id, Non_Limited_View (Typ));
3087 end Detect_And_Exchange;
3093 -- Start of processing for Exchange_Limited_Views
3096 -- Do not process subprogram bodies as they already use the non-
3097 -- limited view of types.
3099 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3103 -- Examine all formals and swap views when applicable
3105 Formal := First_Formal (Subp_Id);
3106 while Present (Formal) loop
3107 Detect_And_Exchange (Formal);
3109 Next_Formal (Formal);
3112 -- Process the return type of a function
3114 if Ekind (Subp_Id) = E_Function then
3115 Detect_And_Exchange (Subp_Id);
3119 end Exchange_Limited_Views;
3121 -------------------------------------
3122 -- Is_Private_Concurrent_Primitive --
3123 -------------------------------------
3125 function Is_Private_Concurrent_Primitive
3126 (Subp_Id : Entity_Id) return Boolean
3128 Formal_Typ : Entity_Id;
3131 if Present (First_Formal (Subp_Id)) then
3132 Formal_Typ := Etype (First_Formal (Subp_Id));
3134 if Is_Concurrent_Record_Type (Formal_Typ) then
3135 if Is_Class_Wide_Type (Formal_Typ) then
3136 Formal_Typ := Root_Type (Formal_Typ);
3139 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3142 -- The type of the first formal is a concurrent tagged type with
3146 Is_Concurrent_Type (Formal_Typ)
3147 and then Is_Tagged_Type (Formal_Typ)
3148 and then Has_Private_Declaration (Formal_Typ);
3152 end Is_Private_Concurrent_Primitive;
3154 -------------------------
3155 -- Mask_Unfrozen_Types --
3156 -------------------------
3158 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3159 Result : Elist_Id := No_Elist;
3161 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3162 -- Mask all types referenced in the subtree rooted at Node
3164 --------------------
3165 -- Mask_Type_Refs --
3166 --------------------
3168 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3169 procedure Mask_Type (Typ : Entity_Id);
3170 -- ??? what does this do?
3176 procedure Mask_Type (Typ : Entity_Id) is
3178 -- Skip Itypes created by the preanalysis
3181 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3186 if not Is_Frozen (Typ) then
3187 if Scope (Typ) /= Current_Scope then
3188 Set_Is_Frozen (Typ);
3189 Append_New_Elmt (Typ, Result);
3191 Freeze_Before (N, Typ);
3196 -- Start of processing for Mask_Type_Refs
3199 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3200 Mask_Type (Etype (Entity (Node)));
3202 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3203 Mask_Type (Scope (Entity (Node)));
3206 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3207 and then Present (Etype (Node))
3209 Mask_Type (Etype (Node));
3215 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3219 Return_Stmt : constant Node_Id :=
3220 First (Statements (Handled_Statement_Sequence (N)));
3222 -- Start of processing for Mask_Unfrozen_Types
3225 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3227 Mask_References (Expression (Return_Stmt));
3230 end Mask_Unfrozen_Types;
3232 ---------------------------
3233 -- Restore_Limited_Views --
3234 ---------------------------
3236 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3237 Elmt : Elmt_Id := First_Elmt (Restore_List);
3241 while Present (Elmt) loop
3244 Set_Etype (Id, Node (Elmt));
3247 end Restore_Limited_Views;
3249 ----------------------------
3250 -- Set_Trivial_Subprogram --
3251 ----------------------------
3253 procedure Set_Trivial_Subprogram (N : Node_Id) is
3254 Nxt : constant Node_Id := Next (N);
3257 Set_Is_Trivial_Subprogram (Body_Id);
3259 if Present (Spec_Id) then
3260 Set_Is_Trivial_Subprogram (Spec_Id);
3264 and then Nkind (Nxt) = N_Simple_Return_Statement
3265 and then No (Next (Nxt))
3266 and then Present (Expression (Nxt))
3267 and then Is_Entity_Name (Expression (Nxt))
3269 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3271 end Set_Trivial_Subprogram;
3273 ---------------------------
3274 -- Unmask_Unfrozen_Types --
3275 ---------------------------
3277 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3278 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3281 while Present (Elmt) loop
3282 Set_Is_Frozen (Node (Elmt), False);
3285 end Unmask_Unfrozen_Types;
3287 ---------------------------------
3288 -- Verify_Overriding_Indicator --
3289 ---------------------------------
3291 procedure Verify_Overriding_Indicator is
3293 if Must_Override (Body_Spec) then
3294 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3295 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3299 elsif not Present (Overridden_Operation (Spec_Id)) then
3301 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3303 -- Overriding indicators aren't allowed for protected subprogram
3304 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3305 -- this to a warning if -gnatd.E is enabled.
3307 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3308 Error_Msg_Warn := Error_To_Warning;
3310 ("<<overriding indicator not allowed for protected "
3311 & "subprogram body", Body_Spec);
3314 elsif Must_Not_Override (Body_Spec) then
3315 if Present (Overridden_Operation (Spec_Id)) then
3317 ("subprogram& overrides inherited operation",
3318 Body_Spec, Spec_Id);
3320 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3321 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3324 ("subprogram& overrides predefined operator ",
3325 Body_Spec, Spec_Id);
3327 -- Overriding indicators aren't allowed for protected subprogram
3328 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3329 -- this to a warning if -gnatd.E is enabled.
3331 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3332 Error_Msg_Warn := Error_To_Warning;
3335 ("<<overriding indicator not allowed "
3336 & "for protected subprogram body", Body_Spec);
3338 -- If this is not a primitive operation, then the overriding
3339 -- indicator is altogether illegal.
3341 elsif not Is_Primitive (Spec_Id) then
3343 ("overriding indicator only allowed "
3344 & "if subprogram is primitive", Body_Spec);
3347 -- If checking the style rule and the operation overrides, then
3348 -- issue a warning about a missing overriding_indicator. Protected
3349 -- subprogram bodies are excluded from this style checking, since
3350 -- they aren't primitives (even though their declarations can
3351 -- override) and aren't allowed to have an overriding_indicator.
3354 and then Present (Overridden_Operation (Spec_Id))
3355 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3357 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3358 Style.Missing_Overriding (N, Body_Id);
3361 and then Can_Override_Operator (Spec_Id)
3362 and then not In_Predefined_Unit (Spec_Id)
3364 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3365 Style.Missing_Overriding (N, Body_Id);
3367 end Verify_Overriding_Indicator;
3371 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3372 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3373 Saved_EA : constant Boolean := Expander_Active;
3374 Saved_ISMP : constant Boolean :=
3375 Ignore_SPARK_Mode_Pragmas_In_Instance;
3376 -- Save the Ghost and SPARK mode-related data to restore on exit
3378 -- Start of processing for Analyze_Subprogram_Body_Helper
3381 -- A [generic] subprogram body freezes the contract of the nearest
3382 -- enclosing package body and all other contracts encountered in the
3383 -- same declarative part up to and excluding the subprogram body:
3385 -- package body Nearest_Enclosing_Package
3386 -- with Refined_State => (State => Constit)
3390 -- procedure Freezes_Enclosing_Package_Body
3391 -- with Refined_Depends => (Input => Constit) ...
3393 -- This ensures that any annotations referenced by the contract of the
3394 -- [generic] subprogram body are available. This form of freezing is
3395 -- decoupled from the usual Freeze_xxx mechanism because it must also
3396 -- work in the context of generics where normal freezing is disabled.
3398 -- Only bodies coming from source should cause this type of freezing.
3399 -- Expression functions that act as bodies and complete an initial
3400 -- declaration must be included in this category, hence the use of
3403 if Comes_From_Source (Original_Node (N)) then
3404 Freeze_Previous_Contracts (N);
3407 -- Generic subprograms are handled separately. They always have a
3408 -- generic specification. Determine whether current scope has a
3409 -- previous declaration.
3411 -- If the subprogram body is defined within an instance of the same
3412 -- name, the instance appears as a package renaming, and will be hidden
3413 -- within the subprogram.
3415 if Present (Prev_Id)
3416 and then not Is_Overloadable (Prev_Id)
3417 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3418 or else Comes_From_Source (Prev_Id))
3420 if Is_Generic_Subprogram (Prev_Id) then
3423 -- A subprogram body is Ghost when it is stand-alone and subject
3424 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3425 -- the mode now to ensure that any nodes generated during analysis
3426 -- and expansion are properly marked as Ghost.
3428 Mark_And_Set_Ghost_Body (N, Spec_Id);
3430 -- If the body completes the initial declaration of a compilation
3431 -- unit which is subject to pragma Elaboration_Checks, set the
3432 -- model specified by the pragma because it applies to all parts
3435 Install_Elaboration_Model (Spec_Id);
3437 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3438 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3440 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3442 if Nkind (N) = N_Subprogram_Body then
3443 HSS := Handled_Statement_Sequence (N);
3444 Check_Missing_Return;
3449 -- Otherwise a previous entity conflicts with the subprogram name.
3450 -- Attempting to enter name will post error.
3453 Enter_Name (Body_Id);
3457 -- Non-generic case, find the subprogram declaration, if one was seen,
3458 -- or enter new overloaded entity in the current scope. If the
3459 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3460 -- part of the context of one of its subunits. No need to redo the
3463 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3467 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3469 if Nkind (N) = N_Subprogram_Body_Stub
3470 or else No (Corresponding_Spec (N))
3472 if Is_Private_Concurrent_Primitive (Body_Id) then
3473 Spec_Id := Disambiguate_Spec;
3475 -- A subprogram body is Ghost when it is stand-alone and
3476 -- subject to pragma Ghost or when the corresponding spec is
3477 -- Ghost. Set the mode now to ensure that any nodes generated
3478 -- during analysis and expansion are properly marked as Ghost.
3480 Mark_And_Set_Ghost_Body (N, Spec_Id);
3482 -- If the body completes a compilation unit which is subject
3483 -- to pragma Elaboration_Checks, set the model specified by
3484 -- the pragma because it applies to all parts of the unit.
3486 Install_Elaboration_Model (Spec_Id);
3489 Spec_Id := Find_Corresponding_Spec (N);
3491 -- A subprogram body is Ghost when it is stand-alone and
3492 -- subject to pragma Ghost or when the corresponding spec is
3493 -- Ghost. Set the mode now to ensure that any nodes generated
3494 -- during analysis and expansion are properly marked as Ghost.
3496 Mark_And_Set_Ghost_Body (N, Spec_Id);
3498 -- If the body completes a compilation unit which is subject
3499 -- to pragma Elaboration_Checks, set the model specified by
3500 -- the pragma because it applies to all parts of the unit.
3502 Install_Elaboration_Model (Spec_Id);
3504 -- In GNATprove mode, if the body has no previous spec, create
3505 -- one so that the inlining machinery can operate properly.
3506 -- Transfer aspects, if any, to the new spec, so that they
3507 -- are legal and can be processed ahead of the body.
3508 -- We make two copies of the given spec, one for the new
3509 -- declaration, and one for the body.
3511 if No (Spec_Id) and then GNATprove_Mode
3513 -- Inlining does not apply during preanalysis of code
3515 and then Full_Analysis
3517 -- Inlining only applies to full bodies, not stubs
3519 and then Nkind (N) /= N_Subprogram_Body_Stub
3521 -- Inlining only applies to bodies in the source code, not to
3522 -- those generated by the compiler. In particular, expression
3523 -- functions, whose body is generated by the compiler, are
3524 -- treated specially by GNATprove.
3526 and then Comes_From_Source (Body_Id)
3528 -- This cannot be done for a compilation unit, which is not
3529 -- in a context where we can insert a new spec.
3531 and then Is_List_Member (N)
3533 -- Inlining only applies to subprograms without contracts,
3534 -- as a contract is a sign that GNATprove should perform a
3535 -- modular analysis of the subprogram instead of a contextual
3536 -- analysis at each call site. The same test is performed in
3537 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3538 -- here in another form (because the contract has not been
3539 -- attached to the body) to avoid front-end errors in case
3540 -- pragmas are used instead of aspects, because the
3541 -- corresponding pragmas in the body would not be transferred
3542 -- to the spec, leading to legality errors.
3544 and then not Body_Has_Contract
3545 and then not Inside_A_Generic
3547 Build_Subprogram_Declaration;
3549 -- If this is a function that returns a constrained array, and
3550 -- we are generating SPARK_For_C, create subprogram declaration
3551 -- to simplify subsequent C generation.
3554 and then Modify_Tree_For_C
3555 and then Nkind (Body_Spec) = N_Function_Specification
3556 and then Is_Array_Type (Etype (Body_Id))
3557 and then Is_Constrained (Etype (Body_Id))
3559 Build_Subprogram_Declaration;
3563 -- If this is a duplicate body, no point in analyzing it
3565 if Error_Posted (N) then
3569 -- A subprogram body should cause freezing of its own declaration,
3570 -- but if there was no previous explicit declaration, then the
3571 -- subprogram will get frozen too late (there may be code within
3572 -- the body that depends on the subprogram having been frozen,
3573 -- such as uses of extra formals), so we force it to be frozen
3574 -- here. Same holds if the body and spec are compilation units.
3575 -- Finally, if the return type is an anonymous access to protected
3576 -- subprogram, it must be frozen before the body because its
3577 -- expansion has generated an equivalent type that is used when
3578 -- elaborating the body.
3580 -- An exception in the case of Ada 2012, AI05-177: The bodies
3581 -- created for expression functions do not freeze.
3584 and then Nkind (Original_Node (N)) /= N_Expression_Function
3586 Freeze_Before (N, Body_Id);
3588 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3589 Freeze_Before (N, Spec_Id);
3591 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3592 Freeze_Before (N, Etype (Body_Id));
3596 Spec_Id := Corresponding_Spec (N);
3598 -- A subprogram body is Ghost when it is stand-alone and subject
3599 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3600 -- the mode now to ensure that any nodes generated during analysis
3601 -- and expansion are properly marked as Ghost.
3603 Mark_And_Set_Ghost_Body (N, Spec_Id);
3605 -- If the body completes the initial declaration of a compilation
3606 -- unit which is subject to pragma Elaboration_Checks, set the
3607 -- model specified by the pragma because it applies to all parts
3610 Install_Elaboration_Model (Spec_Id);
3614 -- Deactivate expansion inside the body of ignored Ghost entities,
3615 -- as this code will ultimately be ignored. This avoids requiring the
3616 -- presence of run-time units which are not needed. Only do this for
3617 -- user entities, as internally generated entitities might still need
3618 -- to be expanded (e.g. those generated for types).
3620 if Present (Ignored_Ghost_Region)
3621 and then Comes_From_Source (Body_Id)
3623 Expander_Active := False;
3626 -- Previously we scanned the body to look for nested subprograms, and
3627 -- rejected an inline directive if nested subprograms were present,
3628 -- because the back-end would generate conflicting symbols for the
3629 -- nested bodies. This is now unnecessary.
3631 -- Look ahead to recognize a pragma Inline that appears after the body
3633 Check_Inline_Pragma (Spec_Id);
3635 -- Deal with special case of a fully private operation in the body of
3636 -- the protected type. We must create a declaration for the subprogram,
3637 -- in order to attach the protected subprogram that will be used in
3638 -- internal calls. We exclude compiler generated bodies from the
3639 -- expander since the issue does not arise for those cases.
3642 and then Comes_From_Source (N)
3643 and then Is_Protected_Type (Current_Scope)
3645 Spec_Id := Build_Private_Protected_Declaration (N);
3648 -- If we are generating C and this is a function returning a constrained
3649 -- array type for which we must create a procedure with an extra out
3650 -- parameter, build and analyze the body now. The procedure declaration
3651 -- has already been created. We reuse the source body of the function,
3652 -- because in an instance it may contain global references that cannot
3653 -- be reanalyzed. The source function itself is not used any further,
3654 -- so we mark it as having a completion. If the subprogram is a stub the
3655 -- transformation is done later, when the proper body is analyzed.
3658 and then Modify_Tree_For_C
3659 and then Present (Spec_Id)
3660 and then Ekind (Spec_Id) = E_Function
3661 and then Nkind (N) /= N_Subprogram_Body_Stub
3662 and then Rewritten_For_C (Spec_Id)
3664 Set_Has_Completion (Spec_Id);
3666 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3669 -- The entity for the created procedure must remain invisible, so it
3670 -- does not participate in resolution of subsequent references to the
3673 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3677 -- If a separate spec is present, then deal with freezing issues
3679 if Present (Spec_Id) then
3680 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3681 Verify_Overriding_Indicator;
3683 -- In general, the spec will be frozen when we start analyzing the
3684 -- body. However, for internally generated operations, such as
3685 -- wrapper functions for inherited operations with controlling
3686 -- results, the spec may not have been frozen by the time we expand
3687 -- the freeze actions that include the bodies. In particular, extra
3688 -- formals for accessibility or for return-in-place may need to be
3689 -- generated. Freeze nodes, if any, are inserted before the current
3690 -- body. These freeze actions are also needed in ASIS mode and in
3691 -- Compile_Only mode to enable the proper back-end type annotations.
3692 -- They are necessary in any case to insure order of elaboration
3695 if Nkind (N) = N_Subprogram_Body
3696 and then Was_Expression_Function (N)
3697 and then not Has_Completion (Spec_Id)
3698 and then Serious_Errors_Detected = 0
3699 and then (Expander_Active
3701 or else Operating_Mode = Check_Semantics)
3703 -- The body generated for an expression function that is not a
3704 -- completion is a freeze point neither for the profile nor for
3705 -- anything else. That's why, in order to prevent any freezing
3706 -- during analysis, we need to mask types declared outside the
3707 -- expression (and in an outer scope) that are not yet frozen.
3709 Set_Is_Frozen (Spec_Id);
3710 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3712 elsif not Is_Frozen (Spec_Id)
3713 and then Serious_Errors_Detected = 0
3715 Set_Has_Delayed_Freeze (Spec_Id);
3716 Freeze_Before (N, Spec_Id);
3720 -- If the subprogram has a class-wide clone, build its body as a copy
3721 -- of the original body, and rewrite body of original subprogram as a
3722 -- wrapper that calls the clone. If N is a stub, this construction will
3723 -- take place when the proper body is analyzed. No action needed if this
3724 -- subprogram has been eliminated.
3726 if Present (Spec_Id)
3727 and then Present (Class_Wide_Clone (Spec_Id))
3728 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3729 and then Nkind (N) /= N_Subprogram_Body_Stub
3730 and then not (Expander_Active and then Is_Eliminated (Spec_Id))
3732 Build_Class_Wide_Clone_Body (Spec_Id, N);
3734 -- This is the new body for the existing primitive operation
3736 Rewrite (N, Build_Class_Wide_Clone_Call
3737 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3738 Set_Has_Completion (Spec_Id, False);
3743 -- Place subprogram on scope stack, and make formals visible. If there
3744 -- is a spec, the visible entity remains that of the spec.
3746 if Present (Spec_Id) then
3747 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3749 if Is_Child_Unit (Spec_Id) then
3750 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3754 Style.Check_Identifier (Body_Id, Spec_Id);
3757 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3758 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3760 if Is_Abstract_Subprogram (Spec_Id) then
3761 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3765 Set_Convention (Body_Id, Convention (Spec_Id));
3766 Set_Has_Completion (Spec_Id);
3768 if Is_Protected_Type (Scope (Spec_Id)) then
3769 Prot_Typ := Scope (Spec_Id);
3772 -- If this is a body generated for a renaming, do not check for
3773 -- full conformance. The check is redundant, because the spec of
3774 -- the body is a copy of the spec in the renaming declaration,
3775 -- and the test can lead to spurious errors on nested defaults.
3777 if Present (Spec_Decl)
3778 and then not Comes_From_Source (N)
3780 (Nkind (Original_Node (Spec_Decl)) =
3781 N_Subprogram_Renaming_Declaration
3782 or else (Present (Corresponding_Body (Spec_Decl))
3784 Nkind (Unit_Declaration_Node
3785 (Corresponding_Body (Spec_Decl))) =
3786 N_Subprogram_Renaming_Declaration))
3790 -- Conversely, the spec may have been generated for specless body
3791 -- with an inline pragma. The entity comes from source, which is
3792 -- both semantically correct and necessary for proper inlining.
3793 -- The subprogram declaration itself is not in the source.
3795 elsif Comes_From_Source (N)
3796 and then Present (Spec_Decl)
3797 and then not Comes_From_Source (Spec_Decl)
3798 and then Has_Pragma_Inline (Spec_Id)
3805 Fully_Conformant, True, Conformant, Body_Id);
3808 -- If the body is not fully conformant, we have to decide if we
3809 -- should analyze it or not. If it has a really messed up profile
3810 -- then we probably should not analyze it, since we will get too
3811 -- many bogus messages.
3813 -- Our decision is to go ahead in the non-fully conformant case
3814 -- only if it is at least mode conformant with the spec. Note
3815 -- that the call to Check_Fully_Conformant has issued the proper
3816 -- error messages to complain about the lack of conformance.
3819 and then not Mode_Conformant (Body_Id, Spec_Id)
3825 -- In the case we are dealing with an expression function we check
3826 -- the formals attached to the spec instead of the body - so we don't
3827 -- reference body formals.
3829 if Spec_Id /= Body_Id
3830 and then not Is_Expression_Function (Spec_Id)
3832 Reference_Body_Formals (Spec_Id, Body_Id);
3835 Set_Ekind (Body_Id, E_Subprogram_Body);
3837 if Nkind (N) = N_Subprogram_Body_Stub then
3838 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3843 Set_Corresponding_Spec (N, Spec_Id);
3845 -- Ada 2005 (AI-345): If the operation is a primitive operation
3846 -- of a concurrent type, the type of the first parameter has been
3847 -- replaced with the corresponding record, which is the proper
3848 -- run-time structure to use. However, within the body there may
3849 -- be uses of the formals that depend on primitive operations
3850 -- of the type (in particular calls in prefixed form) for which
3851 -- we need the original concurrent type. The operation may have
3852 -- several controlling formals, so the replacement must be done
3855 if Comes_From_Source (Spec_Id)
3856 and then Present (First_Entity (Spec_Id))
3857 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3858 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3859 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3860 and then Present (Corresponding_Concurrent_Type
3861 (Etype (First_Entity (Spec_Id))))
3864 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3868 Form := First_Formal (Spec_Id);
3869 while Present (Form) loop
3870 if Etype (Form) = Typ then
3871 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3879 -- Make the formals visible, and place subprogram on scope stack.
3880 -- This is also the point at which we set Last_Real_Spec_Entity
3881 -- to mark the entities which will not be moved to the body.
3883 Install_Formals (Spec_Id);
3884 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3886 -- Within an instance, add local renaming declarations so that
3887 -- gdb can retrieve the values of actuals more easily. This is
3888 -- only relevant if generating code (and indeed we definitely
3889 -- do not want these definitions -gnatc mode, because that would
3892 if Is_Generic_Instance (Spec_Id)
3893 and then Is_Wrapper_Package (Current_Scope)
3894 and then Expander_Active
3896 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3899 Push_Scope (Spec_Id);
3901 -- Make sure that the subprogram is immediately visible. For
3902 -- child units that have no separate spec this is indispensable.
3903 -- Otherwise it is safe albeit redundant.
3905 Set_Is_Immediately_Visible (Spec_Id);
3908 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3909 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3910 Set_Scope (Body_Id, Scope (Spec_Id));
3912 -- Case of subprogram body with no previous spec
3915 -- Check for style warning required
3919 -- Only apply check for source level subprograms for which checks
3920 -- have not been suppressed.
3922 and then Comes_From_Source (Body_Id)
3923 and then not Suppress_Style_Checks (Body_Id)
3925 -- No warnings within an instance
3927 and then not In_Instance
3929 -- No warnings for expression functions
3931 and then Nkind (Original_Node (N)) /= N_Expression_Function
3933 Style.Body_With_No_Spec (N);
3936 New_Overloaded_Entity (Body_Id);
3938 if Nkind (N) /= N_Subprogram_Body_Stub then
3939 Set_Acts_As_Spec (N);
3940 Generate_Definition (Body_Id);
3942 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3944 -- If the body is an entry wrapper created for an entry with
3945 -- preconditions, it must be compiled in the context of the
3946 -- enclosing synchronized object, because it may mention other
3947 -- operations of the type.
3949 if Is_Entry_Wrapper (Body_Id) then
3951 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3954 Install_Declarations (Prot);
3958 Install_Formals (Body_Id);
3960 Push_Scope (Body_Id);
3963 -- For stubs and bodies with no previous spec, generate references to
3966 Generate_Reference_To_Formals (Body_Id);
3969 -- Entry barrier functions are generated outside the protected type and
3970 -- should not carry the SPARK_Mode of the enclosing context.
3972 if Nkind (N) = N_Subprogram_Body
3973 and then Is_Entry_Barrier_Function (N)
3977 -- The body is generated as part of expression function expansion. When
3978 -- the expression function appears in the visible declarations of a
3979 -- package, the body is added to the private declarations. Since both
3980 -- declarative lists may be subject to a different SPARK_Mode, inherit
3981 -- the mode of the spec.
3983 -- package P with SPARK_Mode is
3984 -- function Expr_Func ... is (...); -- original
3985 -- [function Expr_Func ...;] -- generated spec
3988 -- pragma SPARK_Mode (Off);
3989 -- [function Expr_Func ... is return ...;] -- generated body
3990 -- end P; -- mode is ON
3992 elsif not Comes_From_Source (N)
3993 and then Present (Spec_Id)
3994 and then Is_Expression_Function (Spec_Id)
3996 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
3997 Set_SPARK_Pragma_Inherited
3998 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4000 -- Set the SPARK_Mode from the current context (may be overwritten later
4001 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4002 -- initially on a stand-alone subprogram body, but is then relocated to
4003 -- a generated corresponding spec. In this scenario the mode is shared
4004 -- between the spec and body.
4006 elsif No (SPARK_Pragma (Body_Id)) then
4007 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4008 Set_SPARK_Pragma_Inherited (Body_Id);
4011 -- A subprogram body may be instantiated or inlined at a later pass.
4012 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4013 -- applied to the initial declaration of the body.
4015 if Present (Spec_Id) then
4016 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4017 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4021 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4022 -- case the body is instantiated or inlined later and out of context.
4023 -- The body uses this attribute to restore the value of the global
4026 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4027 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4029 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4030 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4034 -- Preserve relevant elaboration-related attributes of the context which
4035 -- are no longer available or very expensive to recompute once analysis,
4036 -- resolution, and expansion are over.
4038 if No (Spec_Id) then
4039 Mark_Elaboration_Attributes
4045 -- If this is the proper body of a stub, we must verify that the stub
4046 -- conforms to the body, and to the previous spec if one was present.
4047 -- We know already that the body conforms to that spec. This test is
4048 -- only required for subprograms that come from source.
4050 if Nkind (Parent (N)) = N_Subunit
4051 and then Comes_From_Source (N)
4052 and then not Error_Posted (Body_Id)
4053 and then Nkind (Corresponding_Stub (Parent (N))) =
4054 N_Subprogram_Body_Stub
4057 Old_Id : constant Entity_Id :=
4059 (Specification (Corresponding_Stub (Parent (N))));
4061 Conformant : Boolean := False;
4064 if No (Spec_Id) then
4065 Check_Fully_Conformant (Body_Id, Old_Id);
4069 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4071 if not Conformant then
4073 -- The stub was taken to be a new declaration. Indicate that
4076 Set_Has_Completion (Old_Id, False);
4082 Set_Has_Completion (Body_Id);
4083 Check_Eliminated (Body_Id);
4085 -- Analyze any aspect specifications that appear on the subprogram body
4086 -- stub. Stop the analysis now as the stub does not have a declarative
4087 -- or a statement part, and it cannot be inlined.
4089 if Nkind (N) = N_Subprogram_Body_Stub then
4090 if Has_Aspects (N) then
4091 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4099 -- Note: Normally we don't do any inlining if expansion is off, since
4100 -- we won't generate code in any case. An exception arises in GNATprove
4101 -- mode where we want to expand some calls in place, even with expansion
4102 -- disabled, since the inlining eases formal verification.
4104 if not GNATprove_Mode
4105 and then Expander_Active
4106 and then Serious_Errors_Detected = 0
4107 and then Present (Spec_Id)
4108 and then Has_Pragma_Inline (Spec_Id)
4110 -- Legacy implementation (relying on front-end inlining)
4112 if not Back_End_Inlining then
4113 if (Has_Pragma_Inline_Always (Spec_Id)
4114 and then not Opt.Disable_FE_Inline_Always)
4115 or else (Front_End_Inlining
4116 and then not Opt.Disable_FE_Inline)
4118 Build_Body_To_Inline (N, Spec_Id);
4121 -- New implementation (relying on back-end inlining)
4124 if Has_Pragma_Inline_Always (Spec_Id)
4125 or else Optimization_Level > 0
4127 -- Handle function returning an unconstrained type
4129 if Comes_From_Source (Body_Id)
4130 and then Ekind (Spec_Id) = E_Function
4131 and then Returns_Unconstrained_Type (Spec_Id)
4133 -- If function builds in place, i.e. returns a limited type,
4134 -- inlining cannot be done.
4136 and then not Is_Limited_Type (Etype (Spec_Id))
4138 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4142 Subp_Body : constant Node_Id :=
4143 Unit_Declaration_Node (Body_Id);
4144 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4147 -- Do not pass inlining to the backend if the subprogram
4148 -- has declarations or statements which cannot be inlined
4149 -- by the backend. This check is done here to emit an
4150 -- error instead of the generic warning message reported
4151 -- by the GCC backend (ie. "function might not be
4154 if Present (Subp_Decl)
4155 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4159 elsif Has_Excluded_Statement
4162 (Handled_Statement_Sequence (Subp_Body)))
4166 -- If the backend inlining is available then at this
4167 -- stage we only have to mark the subprogram as inlined.
4168 -- The expander will take care of registering it in the
4169 -- table of subprograms inlined by the backend a part of
4170 -- processing calls to it (cf. Expand_Call)
4173 Set_Is_Inlined (Spec_Id);
4180 -- In GNATprove mode, inline only when there is a separate subprogram
4181 -- declaration for now, as inlining of subprogram bodies acting as
4182 -- declarations, or subprogram stubs, are not supported by front-end
4183 -- inlining. This inlining should occur after analysis of the body, so
4184 -- that it is known whether the value of SPARK_Mode, which can be
4185 -- defined by a pragma inside the body, is applicable to the body.
4186 -- Inlining can be disabled with switch -gnatdm
4188 elsif GNATprove_Mode
4189 and then Full_Analysis
4190 and then not Inside_A_Generic
4191 and then Present (Spec_Id)
4193 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4194 and then Body_Has_SPARK_Mode_On
4195 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4196 and then not Body_Has_Contract
4197 and then not Debug_Flag_M
4199 Build_Body_To_Inline (N, Spec_Id);
4202 -- When generating code, inherited pre/postconditions are handled when
4203 -- expanding the corresponding contract.
4205 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4206 -- of the specification we have to install the private withed units.
4207 -- This holds for child units as well.
4209 if Is_Compilation_Unit (Body_Id)
4210 or else Nkind (Parent (N)) = N_Compilation_Unit
4212 Install_Private_With_Clauses (Body_Id);
4215 Check_Anonymous_Return;
4217 -- Set the Protected_Formal field of each extra formal of the protected
4218 -- subprogram to reference the corresponding extra formal of the
4219 -- subprogram that implements it. For regular formals this occurs when
4220 -- the protected subprogram's declaration is expanded, but the extra
4221 -- formals don't get created until the subprogram is frozen. We need to
4222 -- do this before analyzing the protected subprogram's body so that any
4223 -- references to the original subprogram's extra formals will be changed
4224 -- refer to the implementing subprogram's formals (see Expand_Formal).
4226 if Present (Spec_Id)
4227 and then Is_Protected_Type (Scope (Spec_Id))
4228 and then Present (Protected_Body_Subprogram (Spec_Id))
4231 Impl_Subp : constant Entity_Id :=
4232 Protected_Body_Subprogram (Spec_Id);
4233 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4234 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4237 while Present (Prot_Ext_Formal) loop
4238 pragma Assert (Present (Impl_Ext_Formal));
4239 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4240 Next_Formal_With_Extras (Prot_Ext_Formal);
4241 Next_Formal_With_Extras (Impl_Ext_Formal);
4246 -- Now we can go on to analyze the body
4248 HSS := Handled_Statement_Sequence (N);
4249 Set_Actual_Subtypes (N, Current_Scope);
4251 -- Add a declaration for the Protection object, renaming declarations
4252 -- for discriminals and privals and finally a declaration for the entry
4253 -- family index (if applicable). This form of early expansion is done
4254 -- when the Expander is active because Install_Private_Data_Declarations
4255 -- references entities which were created during regular expansion. The
4256 -- subprogram entity must come from source, and not be an internally
4257 -- generated subprogram.
4260 and then Present (Prot_Typ)
4261 and then Present (Spec_Id)
4262 and then Comes_From_Source (Spec_Id)
4263 and then not Is_Eliminated (Spec_Id)
4265 Install_Private_Data_Declarations
4266 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4269 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4270 -- may now appear in parameter and result profiles. Since the analysis
4271 -- of a subprogram body may use the parameter and result profile of the
4272 -- spec, swap any limited views with their non-limited counterpart.
4274 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4275 Exch_Views := Exchange_Limited_Views (Spec_Id);
4278 -- If the return type is an anonymous access type whose designated type
4279 -- is the limited view of a class-wide type and the non-limited view is
4280 -- available, update the return type accordingly.
4282 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4288 Rtyp := Etype (Spec_Id);
4290 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4291 Etyp := Directly_Designated_Type (Rtyp);
4293 if Is_Class_Wide_Type (Etyp)
4294 and then From_Limited_With (Etyp)
4297 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4303 -- Analyze any aspect specifications that appear on the subprogram body
4305 if Has_Aspects (N) then
4306 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4309 Analyze_Declarations (Declarations (N));
4311 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4313 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4314 if Present (SPARK_Pragma (Spec_Id)) then
4315 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4317 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4319 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4320 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4321 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4323 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4326 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4330 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4331 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4332 Error_Msg_Sloc := Sloc (Spec_Id);
4334 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4338 -- A subprogram body freezes its own contract. Analyze the contract
4339 -- after the declarations of the body have been processed as pragmas
4340 -- are now chained on the contract of the subprogram body.
4342 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4344 -- Check completion, and analyze the statements
4347 Inspect_Deferred_Constant_Completion (Declarations (N));
4350 -- Deal with end of scope processing for the body
4352 Process_End_Label (HSS, 't', Current_Scope);
4353 Update_Use_Clause_Chain;
4356 -- If we are compiling an entry wrapper, remove the enclosing
4357 -- synchronized object from the stack.
4359 if Is_Entry_Wrapper (Body_Id) then
4363 Check_Subprogram_Order (N);
4364 Set_Analyzed (Body_Id);
4366 -- If we have a separate spec, then the analysis of the declarations
4367 -- caused the entities in the body to be chained to the spec id, but
4368 -- we want them chained to the body id. Only the formal parameters
4369 -- end up chained to the spec id in this case.
4371 if Present (Spec_Id) then
4373 -- We must conform to the categorization of our spec
4375 Validate_Categorization_Dependency (N, Spec_Id);
4377 -- And if this is a child unit, the parent units must conform
4379 if Is_Child_Unit (Spec_Id) then
4380 Validate_Categorization_Dependency
4381 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4384 -- Here is where we move entities from the spec to the body
4386 -- Case where there are entities that stay with the spec
4388 if Present (Last_Real_Spec_Entity) then
4390 -- No body entities (happens when the only real spec entities come
4391 -- from precondition and postcondition pragmas).
4393 if No (Last_Entity (Body_Id)) then
4394 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4396 -- Body entities present (formals), so chain stuff past them
4400 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4403 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4404 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4405 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4407 -- Case where there are no spec entities, in this case there can be
4408 -- no body entities either, so just move everything.
4410 -- If the body is generated for an expression function, it may have
4411 -- been preanalyzed already, if 'access was applied to it.
4414 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4415 N_Expression_Function
4417 pragma Assert (No (Last_Entity (Body_Id)));
4421 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4422 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4423 Set_First_Entity (Spec_Id, Empty);
4424 Set_Last_Entity (Spec_Id, Empty);
4427 -- Otherwise the body does not complete a previous declaration. Check
4428 -- the categorization of the body against the units it withs.
4431 Validate_Categorization_Dependency (N, Body_Id);
4434 Check_Missing_Return;
4436 -- Now we are going to check for variables that are never modified in
4437 -- the body of the procedure. But first we deal with a special case
4438 -- where we want to modify this check. If the body of the subprogram
4439 -- starts with a raise statement or its equivalent, or if the body
4440 -- consists entirely of a null statement, then it is pretty obvious that
4441 -- it is OK to not reference the parameters. For example, this might be
4442 -- the following common idiom for a stubbed function: statement of the
4443 -- procedure raises an exception. In particular this deals with the
4444 -- common idiom of a stubbed function, which appears something like:
4446 -- function F (A : Integer) return Some_Type;
4449 -- raise Program_Error;
4453 -- Here the purpose of X is simply to satisfy the annoying requirement
4454 -- in Ada that there be at least one return, and we certainly do not
4455 -- want to go posting warnings on X that it is not initialized. On
4456 -- the other hand, if X is entirely unreferenced that should still
4459 -- What we do is to detect these cases, and if we find them, flag the
4460 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4461 -- suppress unwanted warnings. For the case of the function stub above
4462 -- we have a special test to set X as apparently assigned to suppress
4469 -- Skip call markers installed by the ABE mechanism, labels, and
4470 -- Push_xxx_Error_Label to find the first real statement.
4472 Stm := First (Statements (HSS));
4473 while Nkind_In (Stm, N_Call_Marker, N_Label)
4474 or else Nkind (Stm) in N_Push_xxx_Label
4479 -- Do the test on the original statement before expansion
4482 Ostm : constant Node_Id := Original_Node (Stm);
4485 -- If explicit raise statement, turn on flag
4487 if Nkind (Ostm) = N_Raise_Statement then
4488 Set_Trivial_Subprogram (Stm);
4490 -- If null statement, and no following statements, turn on flag
4492 elsif Nkind (Stm) = N_Null_Statement
4493 and then Comes_From_Source (Stm)
4494 and then No (Next (Stm))
4496 Set_Trivial_Subprogram (Stm);
4498 -- Check for explicit call cases which likely raise an exception
4500 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4501 if Is_Entity_Name (Name (Ostm)) then
4503 Ent : constant Entity_Id := Entity (Name (Ostm));
4506 -- If the procedure is marked No_Return, then likely it
4507 -- raises an exception, but in any case it is not coming
4508 -- back here, so turn on the flag.
4511 and then Ekind (Ent) = E_Procedure
4512 and then No_Return (Ent)
4514 Set_Trivial_Subprogram (Stm);
4522 -- Check for variables that are never modified
4529 -- If there is a separate spec, then transfer Never_Set_In_Source
4530 -- flags from out parameters to the corresponding entities in the
4531 -- body. The reason we do that is we want to post error flags on
4532 -- the body entities, not the spec entities.
4534 if Present (Spec_Id) then
4535 E1 := First_Entity (Spec_Id);
4536 while Present (E1) loop
4537 if Ekind (E1) = E_Out_Parameter then
4538 E2 := First_Entity (Body_Id);
4539 while Present (E2) loop
4540 exit when Chars (E1) = Chars (E2);
4544 if Present (E2) then
4545 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4553 -- Check references of the subprogram spec when we are dealing with
4554 -- an expression function due to it having a generated body.
4555 -- Otherwise, we simply check the formals of the subprogram body.
4557 if Present (Spec_Id)
4558 and then Is_Expression_Function (Spec_Id)
4560 Check_References (Spec_Id);
4562 Check_References (Body_Id);
4566 -- Check for nested subprogram, and mark outer level subprogram if so
4572 if Present (Spec_Id) then
4579 Ent := Enclosing_Subprogram (Ent);
4580 exit when No (Ent) or else Is_Subprogram (Ent);
4583 if Present (Ent) then
4584 Set_Has_Nested_Subprogram (Ent);
4588 -- Restore the limited views in the spec, if any, to let the back end
4589 -- process it without running into circularities.
4591 if Exch_Views /= No_Elist then
4592 Restore_Limited_Views (Exch_Views);
4595 if Mask_Types /= No_Elist then
4596 Unmask_Unfrozen_Types (Mask_Types);
4599 if Present (Desig_View) then
4600 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4604 if Present (Ignored_Ghost_Region) then
4605 Expander_Active := Saved_EA;
4608 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4609 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4610 end Analyze_Subprogram_Body_Helper;
4612 ------------------------------------
4613 -- Analyze_Subprogram_Declaration --
4614 ------------------------------------
4616 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4617 Scop : constant Entity_Id := Current_Scope;
4618 Designator : Entity_Id;
4620 Is_Completion : Boolean;
4621 -- Indicates whether a null procedure declaration is a completion
4624 -- Null procedures are not allowed in SPARK
4626 if Nkind (Specification (N)) = N_Procedure_Specification
4627 and then Null_Present (Specification (N))
4629 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4631 -- Null procedures are allowed in protected types, following the
4632 -- recent AI12-0147.
4634 if Is_Protected_Type (Current_Scope)
4635 and then Ada_Version < Ada_2012
4637 Error_Msg_N ("protected operation cannot be a null procedure", N);
4640 Analyze_Null_Procedure (N, Is_Completion);
4642 -- The null procedure acts as a body, nothing further is needed
4644 if Is_Completion then
4649 Designator := Analyze_Subprogram_Specification (Specification (N));
4651 -- A reference may already have been generated for the unit name, in
4652 -- which case the following call is redundant. However it is needed for
4653 -- declarations that are the rewriting of an expression function.
4655 Generate_Definition (Designator);
4657 -- Set the SPARK mode from the current context (may be overwritten later
4658 -- with explicit pragma). This is not done for entry barrier functions
4659 -- because they are generated outside the protected type and should not
4660 -- carry the mode of the enclosing context.
4662 if Nkind (N) = N_Subprogram_Declaration
4663 and then Is_Entry_Barrier_Function (N)
4668 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4669 Set_SPARK_Pragma_Inherited (Designator);
4672 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4673 -- the body of this subprogram is instantiated or inlined later and out
4674 -- of context. The body uses this attribute to restore the value of the
4677 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4678 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4681 -- Preserve relevant elaboration-related attributes of the context which
4682 -- are no longer available or very expensive to recompute once analysis,
4683 -- resolution, and expansion are over.
4685 Mark_Elaboration_Attributes
4686 (N_Id => Designator,
4690 if Debug_Flag_C then
4691 Write_Str ("==> subprogram spec ");
4692 Write_Name (Chars (Designator));
4693 Write_Str (" from ");
4694 Write_Location (Sloc (N));
4699 Validate_RCI_Subprogram_Declaration (N);
4700 New_Overloaded_Entity (Designator);
4701 Check_Delayed_Subprogram (Designator);
4703 -- If the type of the first formal of the current subprogram is a non-
4704 -- generic tagged private type, mark the subprogram as being a private
4705 -- primitive. Ditto if this is a function with controlling result, and
4706 -- the return type is currently private. In both cases, the type of the
4707 -- controlling argument or result must be in the current scope for the
4708 -- operation to be primitive.
4710 if Has_Controlling_Result (Designator)
4711 and then Is_Private_Type (Etype (Designator))
4712 and then Scope (Etype (Designator)) = Current_Scope
4713 and then not Is_Generic_Actual_Type (Etype (Designator))
4715 Set_Is_Private_Primitive (Designator);
4717 elsif Present (First_Formal (Designator)) then
4719 Formal_Typ : constant Entity_Id :=
4720 Etype (First_Formal (Designator));
4722 Set_Is_Private_Primitive (Designator,
4723 Is_Tagged_Type (Formal_Typ)
4724 and then Scope (Formal_Typ) = Current_Scope
4725 and then Is_Private_Type (Formal_Typ)
4726 and then not Is_Generic_Actual_Type (Formal_Typ));
4730 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4733 if Ada_Version >= Ada_2005
4734 and then Comes_From_Source (N)
4735 and then Is_Dispatching_Operation (Designator)
4742 if Has_Controlling_Result (Designator) then
4743 Etyp := Etype (Designator);
4746 E := First_Entity (Designator);
4748 and then Is_Formal (E)
4749 and then not Is_Controlling_Formal (E)
4757 if Is_Access_Type (Etyp) then
4758 Etyp := Directly_Designated_Type (Etyp);
4761 if Is_Interface (Etyp)
4762 and then not Is_Abstract_Subprogram (Designator)
4763 and then not (Ekind (Designator) = E_Procedure
4764 and then Null_Present (Specification (N)))
4766 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4768 -- Specialize error message based on procedures vs. functions,
4769 -- since functions can't be null subprograms.
4771 if Ekind (Designator) = E_Procedure then
4773 ("interface procedure % must be abstract or null", N);
4776 ("interface function % must be abstract", N);
4782 -- What is the following code for, it used to be
4784 -- ??? Set_Suppress_Elaboration_Checks
4785 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4787 -- The following seems equivalent, but a bit dubious
4789 if Elaboration_Checks_Suppressed (Designator) then
4790 Set_Kill_Elaboration_Checks (Designator);
4793 -- For a compilation unit, set body required. This flag will only be
4794 -- reset if a valid Import or Interface pragma is processed later on.
4796 if Nkind (Parent (N)) = N_Compilation_Unit then
4797 Set_Body_Required (Parent (N), True);
4799 if Ada_Version >= Ada_2005
4800 and then Nkind (Specification (N)) = N_Procedure_Specification
4801 and then Null_Present (Specification (N))
4804 ("null procedure cannot be declared at library level", N);
4808 Generate_Reference_To_Formals (Designator);
4809 Check_Eliminated (Designator);
4811 if Debug_Flag_C then
4813 Write_Str ("<== subprogram spec ");
4814 Write_Name (Chars (Designator));
4815 Write_Str (" from ");
4816 Write_Location (Sloc (N));
4820 -- Indicate that this is a protected operation, because it may be used
4821 -- in subsequent declarations within the protected type.
4823 if Is_Protected_Type (Current_Scope) then
4824 Set_Convention (Designator, Convention_Protected);
4827 List_Inherited_Pre_Post_Aspects (Designator);
4829 -- Process the aspects before establishing the proper categorization in
4830 -- case the subprogram is a compilation unit and one of its aspects is
4831 -- converted into a categorization pragma.
4833 if Has_Aspects (N) then
4834 Analyze_Aspect_Specifications (N, Designator);
4837 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4838 Set_Categorization_From_Scope (Designator, Scop);
4840 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4841 -- proper categorization of the unit based on its pragmas.
4844 Push_Scope (Designator);
4845 Set_Categorization_From_Pragmas (N);
4846 Validate_Categorization_Dependency (N, Designator);
4849 end Analyze_Subprogram_Declaration;
4851 --------------------------------------
4852 -- Analyze_Subprogram_Specification --
4853 --------------------------------------
4855 -- Reminder: N here really is a subprogram specification (not a subprogram
4856 -- declaration). This procedure is called to analyze the specification in
4857 -- both subprogram bodies and subprogram declarations (specs).
4859 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4860 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4861 -- Determine whether entity E denotes the spec or body of an invariant
4864 ------------------------------------
4865 -- Is_Invariant_Procedure_Or_Body --
4866 ------------------------------------
4868 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4869 Decl : constant Node_Id := Unit_Declaration_Node (E);
4873 if Nkind (Decl) = N_Subprogram_Body then
4874 Spec := Corresponding_Spec (Decl);
4881 and then Ekind (Spec) = E_Procedure
4882 and then (Is_Partial_Invariant_Procedure (Spec)
4883 or else Is_Invariant_Procedure (Spec));
4884 end Is_Invariant_Procedure_Or_Body;
4888 Designator : constant Entity_Id := Defining_Entity (N);
4889 Formals : constant List_Id := Parameter_Specifications (N);
4891 -- Start of processing for Analyze_Subprogram_Specification
4894 -- User-defined operator is not allowed in SPARK, except as a renaming
4896 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4897 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4899 Check_SPARK_05_Restriction
4900 ("user-defined operator is not allowed", N);
4903 -- Proceed with analysis. Do not emit a cross-reference entry if the
4904 -- specification comes from an expression function, because it may be
4905 -- the completion of a previous declaration. If it is not, the cross-
4906 -- reference entry will be emitted for the new subprogram declaration.
4908 if Nkind (Parent (N)) /= N_Expression_Function then
4909 Generate_Definition (Designator);
4912 if Nkind (N) = N_Function_Specification then
4913 Set_Ekind (Designator, E_Function);
4914 Set_Mechanism (Designator, Default_Mechanism);
4916 Set_Ekind (Designator, E_Procedure);
4917 Set_Etype (Designator, Standard_Void_Type);
4920 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4921 -- those subprograms which could be inlined in GNATprove mode (because
4922 -- Body_To_Inline is non-Empty) but should not be inlined.
4924 if GNATprove_Mode then
4925 Set_Is_Inlined_Always (Designator);
4928 -- Introduce new scope for analysis of the formals and the return type
4930 Set_Scope (Designator, Current_Scope);
4932 if Present (Formals) then
4933 Push_Scope (Designator);
4934 Process_Formals (Formals, N);
4936 -- Check dimensions in N for formals with default expression
4938 Analyze_Dimension_Formals (N, Formals);
4940 -- Ada 2005 (AI-345): If this is an overriding operation of an
4941 -- inherited interface operation, and the controlling type is
4942 -- a synchronized type, replace the type with its corresponding
4943 -- record, to match the proper signature of an overriding operation.
4944 -- Same processing for an access parameter whose designated type is
4945 -- derived from a synchronized interface.
4947 -- This modification is not done for invariant procedures because
4948 -- the corresponding record may not necessarely be visible when the
4949 -- concurrent type acts as the full view of a private type.
4952 -- type Prot is private with Type_Invariant => ...;
4953 -- procedure ConcInvariant (Obj : Prot);
4955 -- protected type Prot is ...;
4956 -- type Concurrent_Record_Prot is record ...;
4957 -- procedure ConcInvariant (Obj : Prot) is
4959 -- end ConcInvariant;
4962 -- In the example above, both the spec and body of the invariant
4963 -- procedure must utilize the private type as the controlling type.
4965 if Ada_Version >= Ada_2005
4966 and then not Is_Invariant_Procedure_Or_Body (Designator)
4970 Formal_Typ : Entity_Id;
4971 Rec_Typ : Entity_Id;
4972 Desig_Typ : Entity_Id;
4975 Formal := First_Formal (Designator);
4976 while Present (Formal) loop
4977 Formal_Typ := Etype (Formal);
4979 if Is_Concurrent_Type (Formal_Typ)
4980 and then Present (Corresponding_Record_Type (Formal_Typ))
4982 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4984 if Present (Interfaces (Rec_Typ)) then
4985 Set_Etype (Formal, Rec_Typ);
4988 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4989 Desig_Typ := Designated_Type (Formal_Typ);
4991 if Is_Concurrent_Type (Desig_Typ)
4992 and then Present (Corresponding_Record_Type (Desig_Typ))
4994 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4996 if Present (Interfaces (Rec_Typ)) then
4997 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5002 Next_Formal (Formal);
5009 -- The subprogram scope is pushed and popped around the processing of
5010 -- the return type for consistency with call above to Process_Formals
5011 -- (which itself can call Analyze_Return_Type), and to ensure that any
5012 -- itype created for the return type will be associated with the proper
5015 elsif Nkind (N) = N_Function_Specification then
5016 Push_Scope (Designator);
5017 Analyze_Return_Type (N);
5023 if Nkind (N) = N_Function_Specification then
5025 -- Deal with operator symbol case
5027 if Nkind (Designator) = N_Defining_Operator_Symbol then
5028 Valid_Operator_Definition (Designator);
5031 May_Need_Actuals (Designator);
5033 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5034 -- the subprogram is abstract also. This does not apply to renaming
5035 -- declarations, where abstractness is inherited, and to subprogram
5036 -- bodies generated for stream operations, which become renamings as
5039 -- In case of primitives associated with abstract interface types
5040 -- the check is applied later (see Analyze_Subprogram_Declaration).
5042 if not Nkind_In (Original_Node (Parent (N)),
5043 N_Abstract_Subprogram_Declaration,
5044 N_Formal_Abstract_Subprogram_Declaration,
5045 N_Subprogram_Renaming_Declaration)
5047 if Is_Abstract_Type (Etype (Designator))
5048 and then not Is_Interface (Etype (Designator))
5051 ("function that returns abstract type must be abstract", N);
5053 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5054 -- access result whose designated type is abstract.
5056 elsif Ada_Version >= Ada_2012
5057 and then Nkind (Result_Definition (N)) = N_Access_Definition
5059 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5060 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5063 ("function whose access result designates abstract type "
5064 & "must be abstract", N);
5070 end Analyze_Subprogram_Specification;
5072 -----------------------
5073 -- Check_Conformance --
5074 -----------------------
5076 procedure Check_Conformance
5077 (New_Id : Entity_Id;
5079 Ctype : Conformance_Type;
5081 Conforms : out Boolean;
5082 Err_Loc : Node_Id := Empty;
5083 Get_Inst : Boolean := False;
5084 Skip_Controlling_Formals : Boolean := False)
5086 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5087 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5088 -- If Errmsg is True, then processing continues to post an error message
5089 -- for conformance error on given node. Two messages are output. The
5090 -- first message points to the previous declaration with a general "no
5091 -- conformance" message. The second is the detailed reason, supplied as
5092 -- Msg. The parameter N provide information for a possible & insertion
5093 -- in the message, and also provides the location for posting the
5094 -- message in the absence of a specified Err_Loc location.
5096 function Conventions_Match
5098 Id2 : Entity_Id) return Boolean;
5099 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5102 -----------------------
5103 -- Conformance_Error --
5104 -----------------------
5106 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5113 if No (Err_Loc) then
5119 Error_Msg_Sloc := Sloc (Old_Id);
5122 when Type_Conformant =>
5123 Error_Msg_N -- CODEFIX
5124 ("not type conformant with declaration#!", Enode);
5126 when Mode_Conformant =>
5127 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5129 ("not mode conformant with operation inherited#!",
5133 ("not mode conformant with declaration#!", Enode);
5136 when Subtype_Conformant =>
5137 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5139 ("not subtype conformant with operation inherited#!",
5143 ("not subtype conformant with declaration#!", Enode);
5146 when Fully_Conformant =>
5147 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5148 Error_Msg_N -- CODEFIX
5149 ("not fully conformant with operation inherited#!",
5152 Error_Msg_N -- CODEFIX
5153 ("not fully conformant with declaration#!", Enode);
5157 Error_Msg_NE (Msg, Enode, N);
5159 end Conformance_Error;
5161 -----------------------
5162 -- Conventions_Match --
5163 -----------------------
5165 function Conventions_Match
5167 Id2 : Entity_Id) return Boolean
5170 -- Ignore the conventions of anonymous access-to-subprogram types
5171 -- and subprogram types because these are internally generated and
5172 -- the only way these may receive a convention is if they inherit
5173 -- the convention of a related subprogram.
5175 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5178 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5183 -- Otherwise compare the conventions directly
5186 return Convention (Id1) = Convention (Id2);
5188 end Conventions_Match;
5192 Old_Type : constant Entity_Id := Etype (Old_Id);
5193 New_Type : constant Entity_Id := Etype (New_Id);
5194 Old_Formal : Entity_Id;
5195 New_Formal : Entity_Id;
5196 Access_Types_Match : Boolean;
5197 Old_Formal_Base : Entity_Id;
5198 New_Formal_Base : Entity_Id;
5200 -- Start of processing for Check_Conformance
5205 -- We need a special case for operators, since they don't appear
5208 if Ctype = Type_Conformant then
5209 if Ekind (New_Id) = E_Operator
5210 and then Operator_Matches_Spec (New_Id, Old_Id)
5216 -- If both are functions/operators, check return types conform
5218 if Old_Type /= Standard_Void_Type
5220 New_Type /= Standard_Void_Type
5222 -- If we are checking interface conformance we omit controlling
5223 -- arguments and result, because we are only checking the conformance
5224 -- of the remaining parameters.
5226 if Has_Controlling_Result (Old_Id)
5227 and then Has_Controlling_Result (New_Id)
5228 and then Skip_Controlling_Formals
5232 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5233 if Ctype >= Subtype_Conformant
5234 and then not Predicates_Match (Old_Type, New_Type)
5237 ("\predicate of return type does not match!", New_Id);
5240 ("\return type does not match!", New_Id);
5246 -- Ada 2005 (AI-231): In case of anonymous access types check the
5247 -- null-exclusion and access-to-constant attributes match.
5249 if Ada_Version >= Ada_2005
5250 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5252 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5253 or else Is_Access_Constant (Etype (Old_Type)) /=
5254 Is_Access_Constant (Etype (New_Type)))
5256 Conformance_Error ("\return type does not match!", New_Id);
5260 -- If either is a function/operator and the other isn't, error
5262 elsif Old_Type /= Standard_Void_Type
5263 or else New_Type /= Standard_Void_Type
5265 Conformance_Error ("\functions can only match functions!", New_Id);
5269 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5270 -- If this is a renaming as body, refine error message to indicate that
5271 -- the conflict is with the original declaration. If the entity is not
5272 -- frozen, the conventions don't have to match, the one of the renamed
5273 -- entity is inherited.
5275 if Ctype >= Subtype_Conformant then
5276 if not Conventions_Match (Old_Id, New_Id) then
5277 if not Is_Frozen (New_Id) then
5280 elsif Present (Err_Loc)
5281 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5282 and then Present (Corresponding_Spec (Err_Loc))
5284 Error_Msg_Name_1 := Chars (New_Id);
5286 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5287 Conformance_Error ("\prior declaration for% has convention %!");
5290 Conformance_Error ("\calling conventions do not match!");
5295 elsif Is_Formal_Subprogram (Old_Id)
5296 or else Is_Formal_Subprogram (New_Id)
5297 or else (Is_Subprogram (New_Id)
5298 and then Present (Alias (New_Id))
5299 and then Is_Formal_Subprogram (Alias (New_Id)))
5302 ("\formal subprograms are not subtype conformant "
5303 & "(RM 6.3.1 (17/3))");
5307 -- Deal with parameters
5309 -- Note: we use the entity information, rather than going directly
5310 -- to the specification in the tree. This is not only simpler, but
5311 -- absolutely necessary for some cases of conformance tests between
5312 -- operators, where the declaration tree simply does not exist.
5314 Old_Formal := First_Formal (Old_Id);
5315 New_Formal := First_Formal (New_Id);
5316 while Present (Old_Formal) and then Present (New_Formal) loop
5317 if Is_Controlling_Formal (Old_Formal)
5318 and then Is_Controlling_Formal (New_Formal)
5319 and then Skip_Controlling_Formals
5321 -- The controlling formals will have different types when
5322 -- comparing an interface operation with its match, but both
5323 -- or neither must be access parameters.
5325 if Is_Access_Type (Etype (Old_Formal))
5327 Is_Access_Type (Etype (New_Formal))
5329 goto Skip_Controlling_Formal;
5332 ("\access parameter does not match!", New_Formal);
5336 -- Ada 2012: Mode conformance also requires that formal parameters
5337 -- be both aliased, or neither.
5339 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5340 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5342 ("\aliased parameter mismatch!", New_Formal);
5346 if Ctype = Fully_Conformant then
5348 -- Names must match. Error message is more accurate if we do
5349 -- this before checking that the types of the formals match.
5351 if Chars (Old_Formal) /= Chars (New_Formal) then
5352 Conformance_Error ("\name& does not match!", New_Formal);
5354 -- Set error posted flag on new formal as well to stop
5355 -- junk cascaded messages in some cases.
5357 Set_Error_Posted (New_Formal);
5361 -- Null exclusion must match
5363 if Null_Exclusion_Present (Parent (Old_Formal))
5365 Null_Exclusion_Present (Parent (New_Formal))
5367 -- Only give error if both come from source. This should be
5368 -- investigated some time, since it should not be needed ???
5370 if Comes_From_Source (Old_Formal)
5372 Comes_From_Source (New_Formal)
5375 ("\null exclusion for& does not match", New_Formal);
5377 -- Mark error posted on the new formal to avoid duplicated
5378 -- complaint about types not matching.
5380 Set_Error_Posted (New_Formal);
5385 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5386 -- case occurs whenever a subprogram is being renamed and one of its
5387 -- parameters imposes a null exclusion. For example:
5389 -- type T is null record;
5390 -- type Acc_T is access T;
5391 -- subtype Acc_T_Sub is Acc_T;
5393 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5394 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5397 Old_Formal_Base := Etype (Old_Formal);
5398 New_Formal_Base := Etype (New_Formal);
5401 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5402 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5405 Access_Types_Match := Ada_Version >= Ada_2005
5407 -- Ensure that this rule is only applied when New_Id is a
5408 -- renaming of Old_Id.
5410 and then Nkind (Parent (Parent (New_Id))) =
5411 N_Subprogram_Renaming_Declaration
5412 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5413 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5414 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5416 -- Now handle the allowed access-type case
5418 and then Is_Access_Type (Old_Formal_Base)
5419 and then Is_Access_Type (New_Formal_Base)
5421 -- The type kinds must match. The only exception occurs with
5422 -- multiple generics of the form:
5425 -- type F is private; type A is private;
5426 -- type F_Ptr is access F; type A_Ptr is access A;
5427 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5428 -- package F_Pack is ... package A_Pack is
5429 -- package F_Inst is
5430 -- new F_Pack (A, A_Ptr, A_P);
5432 -- When checking for conformance between the parameters of A_P
5433 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5434 -- because the compiler has transformed A_Ptr into a subtype of
5435 -- F_Ptr. We catch this case in the code below.
5437 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5439 (Is_Generic_Type (Old_Formal_Base)
5440 and then Is_Generic_Type (New_Formal_Base)
5441 and then Is_Internal (New_Formal_Base)
5442 and then Etype (Etype (New_Formal_Base)) =
5444 and then Directly_Designated_Type (Old_Formal_Base) =
5445 Directly_Designated_Type (New_Formal_Base)
5446 and then ((Is_Itype (Old_Formal_Base)
5447 and then (Can_Never_Be_Null (Old_Formal_Base)
5448 or else Is_Access_Constant
5451 (Is_Itype (New_Formal_Base)
5452 and then (Can_Never_Be_Null (New_Formal_Base)
5453 or else Is_Access_Constant
5454 (New_Formal_Base))));
5456 -- Types must always match. In the visible part of an instance,
5457 -- usual overloading rules for dispatching operations apply, and
5458 -- we check base types (not the actual subtypes).
5460 if In_Instance_Visible_Part
5461 and then Is_Dispatching_Operation (New_Id)
5463 if not Conforming_Types
5464 (T1 => Base_Type (Etype (Old_Formal)),
5465 T2 => Base_Type (Etype (New_Formal)),
5467 Get_Inst => Get_Inst)
5468 and then not Access_Types_Match
5470 Conformance_Error ("\type of & does not match!", New_Formal);
5474 elsif not Conforming_Types
5475 (T1 => Old_Formal_Base,
5476 T2 => New_Formal_Base,
5478 Get_Inst => Get_Inst)
5479 and then not Access_Types_Match
5481 -- Don't give error message if old type is Any_Type. This test
5482 -- avoids some cascaded errors, e.g. in case of a bad spec.
5484 if Errmsg and then Old_Formal_Base = Any_Type then
5487 if Ctype >= Subtype_Conformant
5489 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5492 ("\predicate of & does not match!", New_Formal);
5495 ("\type of & does not match!", New_Formal);
5497 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5499 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5507 -- For mode conformance, mode must match
5509 if Ctype >= Mode_Conformant then
5510 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5511 if not Ekind_In (New_Id, E_Function, E_Procedure)
5512 or else not Is_Primitive_Wrapper (New_Id)
5514 Conformance_Error ("\mode of & does not match!", New_Formal);
5518 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5520 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5522 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5525 ("\mode of & does not match!", New_Formal);
5532 -- Part of mode conformance for access types is having the same
5533 -- constant modifier.
5535 elsif Access_Types_Match
5536 and then Is_Access_Constant (Old_Formal_Base) /=
5537 Is_Access_Constant (New_Formal_Base)
5540 ("\constant modifier does not match!", New_Formal);
5545 if Ctype >= Subtype_Conformant then
5547 -- Ada 2005 (AI-231): In case of anonymous access types check
5548 -- the null-exclusion and access-to-constant attributes must
5549 -- match. For null exclusion, we test the types rather than the
5550 -- formals themselves, since the attribute is only set reliably
5551 -- on the formals in the Ada 95 case, and we exclude the case
5552 -- where Old_Formal is marked as controlling, to avoid errors
5553 -- when matching completing bodies with dispatching declarations
5554 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5556 if Ada_Version >= Ada_2005
5557 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5558 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5560 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5561 Can_Never_Be_Null (Etype (New_Formal))
5563 not Is_Controlling_Formal (Old_Formal))
5565 Is_Access_Constant (Etype (Old_Formal)) /=
5566 Is_Access_Constant (Etype (New_Formal)))
5568 -- Do not complain if error already posted on New_Formal. This
5569 -- avoids some redundant error messages.
5571 and then not Error_Posted (New_Formal)
5573 -- It is allowed to omit the null-exclusion in case of stream
5574 -- attribute subprograms. We recognize stream subprograms
5575 -- through their TSS-generated suffix.
5578 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5581 if TSS_Name /= TSS_Stream_Read
5582 and then TSS_Name /= TSS_Stream_Write
5583 and then TSS_Name /= TSS_Stream_Input
5584 and then TSS_Name /= TSS_Stream_Output
5586 -- Here we have a definite conformance error. It is worth
5587 -- special casing the error message for the case of a
5588 -- controlling formal (which excludes null).
5590 if Is_Controlling_Formal (New_Formal) then
5591 Error_Msg_Node_2 := Scope (New_Formal);
5593 ("\controlling formal & of & excludes null, "
5594 & "declaration must exclude null as well",
5597 -- Normal case (couldn't we give more detail here???)
5601 ("\type of & does not match!", New_Formal);
5610 -- Full conformance checks
5612 if Ctype = Fully_Conformant then
5614 -- We have checked already that names match
5616 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5618 -- Check default expressions for in parameters
5621 NewD : constant Boolean :=
5622 Present (Default_Value (New_Formal));
5623 OldD : constant Boolean :=
5624 Present (Default_Value (Old_Formal));
5626 if NewD or OldD then
5628 -- The old default value has been analyzed because the
5629 -- current full declaration will have frozen everything
5630 -- before. The new default value has not been analyzed,
5631 -- so analyze it now before we check for conformance.
5634 Push_Scope (New_Id);
5635 Preanalyze_Spec_Expression
5636 (Default_Value (New_Formal), Etype (New_Formal));
5640 if not (NewD and OldD)
5641 or else not Fully_Conformant_Expressions
5642 (Default_Value (Old_Formal),
5643 Default_Value (New_Formal))
5646 ("\default expression for & does not match!",
5655 -- A couple of special checks for Ada 83 mode. These checks are
5656 -- skipped if either entity is an operator in package Standard,
5657 -- or if either old or new instance is not from the source program.
5659 if Ada_Version = Ada_83
5660 and then Sloc (Old_Id) > Standard_Location
5661 and then Sloc (New_Id) > Standard_Location
5662 and then Comes_From_Source (Old_Id)
5663 and then Comes_From_Source (New_Id)
5666 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5667 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5670 -- Explicit IN must be present or absent in both cases. This
5671 -- test is required only in the full conformance case.
5673 if In_Present (Old_Param) /= In_Present (New_Param)
5674 and then Ctype = Fully_Conformant
5677 ("\(Ada 83) IN must appear in both declarations",
5682 -- Grouping (use of comma in param lists) must be the same
5683 -- This is where we catch a misconformance like:
5686 -- A : Integer; B : Integer
5688 -- which are represented identically in the tree except
5689 -- for the setting of the flags More_Ids and Prev_Ids.
5691 if More_Ids (Old_Param) /= More_Ids (New_Param)
5692 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5695 ("\grouping of & does not match!", New_Formal);
5701 -- This label is required when skipping controlling formals
5703 <<Skip_Controlling_Formal>>
5705 Next_Formal (Old_Formal);
5706 Next_Formal (New_Formal);
5709 if Present (Old_Formal) then
5710 Conformance_Error ("\too few parameters!");
5713 elsif Present (New_Formal) then
5714 Conformance_Error ("\too many parameters!", New_Formal);
5717 end Check_Conformance;
5719 -----------------------
5720 -- Check_Conventions --
5721 -----------------------
5723 procedure Check_Conventions (Typ : Entity_Id) is
5724 Ifaces_List : Elist_Id;
5726 procedure Check_Convention (Op : Entity_Id);
5727 -- Verify that the convention of inherited dispatching operation Op is
5728 -- consistent among all subprograms it overrides. In order to minimize
5729 -- the search, Search_From is utilized to designate a specific point in
5730 -- the list rather than iterating over the whole list once more.
5732 ----------------------
5733 -- Check_Convention --
5734 ----------------------
5736 procedure Check_Convention (Op : Entity_Id) is
5737 Op_Conv : constant Convention_Id := Convention (Op);
5738 Iface_Conv : Convention_Id;
5739 Iface_Elmt : Elmt_Id;
5740 Iface_Prim_Elmt : Elmt_Id;
5741 Iface_Prim : Entity_Id;
5744 Iface_Elmt := First_Elmt (Ifaces_List);
5745 while Present (Iface_Elmt) loop
5747 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5748 while Present (Iface_Prim_Elmt) loop
5749 Iface_Prim := Node (Iface_Prim_Elmt);
5750 Iface_Conv := Convention (Iface_Prim);
5752 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5753 and then Iface_Conv /= Op_Conv
5756 ("inconsistent conventions in primitive operations", Typ);
5758 Error_Msg_Name_1 := Chars (Op);
5759 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5760 Error_Msg_Sloc := Sloc (Op);
5762 if Comes_From_Source (Op) or else No (Alias (Op)) then
5763 if not Present (Overridden_Operation (Op)) then
5764 Error_Msg_N ("\\primitive % defined #", Typ);
5767 ("\\overriding operation % with "
5768 & "convention % defined #", Typ);
5771 else pragma Assert (Present (Alias (Op)));
5772 Error_Msg_Sloc := Sloc (Alias (Op));
5773 Error_Msg_N ("\\inherited operation % with "
5774 & "convention % defined #", Typ);
5777 Error_Msg_Name_1 := Chars (Op);
5778 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5779 Error_Msg_Sloc := Sloc (Iface_Prim);
5780 Error_Msg_N ("\\overridden operation % with "
5781 & "convention % defined #", Typ);
5783 -- Avoid cascading errors
5788 Next_Elmt (Iface_Prim_Elmt);
5791 Next_Elmt (Iface_Elmt);
5793 end Check_Convention;
5797 Prim_Op : Entity_Id;
5798 Prim_Op_Elmt : Elmt_Id;
5800 -- Start of processing for Check_Conventions
5803 if not Has_Interfaces (Typ) then
5807 Collect_Interfaces (Typ, Ifaces_List);
5809 -- The algorithm checks every overriding dispatching operation against
5810 -- all the corresponding overridden dispatching operations, detecting
5811 -- differences in conventions.
5813 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5814 while Present (Prim_Op_Elmt) loop
5815 Prim_Op := Node (Prim_Op_Elmt);
5817 -- A small optimization: skip the predefined dispatching operations
5818 -- since they always have the same convention.
5820 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5821 Check_Convention (Prim_Op);
5824 Next_Elmt (Prim_Op_Elmt);
5826 end Check_Conventions;
5828 ------------------------------
5829 -- Check_Delayed_Subprogram --
5830 ------------------------------
5832 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5833 procedure Possible_Freeze (T : Entity_Id);
5834 -- T is the type of either a formal parameter or of the return type. If
5835 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5836 -- itself must be delayed.
5838 ---------------------
5839 -- Possible_Freeze --
5840 ---------------------
5842 procedure Possible_Freeze (T : Entity_Id) is
5843 Scop : constant Entity_Id := Scope (Designator);
5846 -- If the subprogram appears within a package instance (which may be
5847 -- the wrapper package of a subprogram instance) the freeze node for
5848 -- that package will freeze the subprogram at the proper place, so
5849 -- do not emit a freeze node for the subprogram, given that it may
5850 -- appear in the wrong scope.
5852 if Ekind (Scop) = E_Package
5853 and then not Comes_From_Source (Scop)
5854 and then Is_Generic_Instance (Scop)
5858 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5859 Set_Has_Delayed_Freeze (Designator);
5861 elsif Is_Access_Type (T)
5862 and then Has_Delayed_Freeze (Designated_Type (T))
5863 and then not Is_Frozen (Designated_Type (T))
5865 Set_Has_Delayed_Freeze (Designator);
5867 end Possible_Freeze;
5873 -- Start of processing for Check_Delayed_Subprogram
5876 -- All subprograms, including abstract subprograms, may need a freeze
5877 -- node if some formal type or the return type needs one.
5879 Possible_Freeze (Etype (Designator));
5880 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5882 -- Need delayed freeze if any of the formal types themselves need a
5883 -- delayed freeze and are not yet frozen.
5885 F := First_Formal (Designator);
5886 while Present (F) loop
5887 Possible_Freeze (Etype (F));
5888 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5892 -- Mark functions that return by reference. Note that it cannot be done
5893 -- for delayed_freeze subprograms because the underlying returned type
5894 -- may not be known yet (for private types).
5896 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5898 Typ : constant Entity_Id := Etype (Designator);
5899 Utyp : constant Entity_Id := Underlying_Type (Typ);
5902 if Is_Limited_View (Typ) then
5903 Set_Returns_By_Ref (Designator);
5905 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5906 Set_Returns_By_Ref (Designator);
5910 end Check_Delayed_Subprogram;
5912 ------------------------------------
5913 -- Check_Discriminant_Conformance --
5914 ------------------------------------
5916 procedure Check_Discriminant_Conformance
5921 Old_Discr : Entity_Id := First_Discriminant (Prev);
5922 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5923 New_Discr_Id : Entity_Id;
5924 New_Discr_Type : Entity_Id;
5926 procedure Conformance_Error (Msg : String; N : Node_Id);
5927 -- Post error message for conformance error on given node. Two messages
5928 -- are output. The first points to the previous declaration with a
5929 -- general "no conformance" message. The second is the detailed reason,
5930 -- supplied as Msg. The parameter N provide information for a possible
5931 -- & insertion in the message.
5933 -----------------------
5934 -- Conformance_Error --
5935 -----------------------
5937 procedure Conformance_Error (Msg : String; N : Node_Id) is
5939 Error_Msg_Sloc := Sloc (Prev_Loc);
5940 Error_Msg_N -- CODEFIX
5941 ("not fully conformant with declaration#!", N);
5942 Error_Msg_NE (Msg, N, N);
5943 end Conformance_Error;
5945 -- Start of processing for Check_Discriminant_Conformance
5948 while Present (Old_Discr) and then Present (New_Discr) loop
5949 New_Discr_Id := Defining_Identifier (New_Discr);
5951 -- The subtype mark of the discriminant on the full type has not
5952 -- been analyzed so we do it here. For an access discriminant a new
5955 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5957 Access_Definition (N, Discriminant_Type (New_Discr));
5960 Analyze (Discriminant_Type (New_Discr));
5961 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5963 -- Ada 2005: if the discriminant definition carries a null
5964 -- exclusion, create an itype to check properly for consistency
5965 -- with partial declaration.
5967 if Is_Access_Type (New_Discr_Type)
5968 and then Null_Exclusion_Present (New_Discr)
5971 Create_Null_Excluding_Itype
5972 (T => New_Discr_Type,
5973 Related_Nod => New_Discr,
5974 Scope_Id => Current_Scope);
5978 if not Conforming_Types
5979 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5981 Conformance_Error ("type of & does not match!", New_Discr_Id);
5984 -- Treat the new discriminant as an occurrence of the old one,
5985 -- for navigation purposes, and fill in some semantic
5986 -- information, for completeness.
5988 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5989 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5990 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5995 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5996 Conformance_Error ("name & does not match!", New_Discr_Id);
6000 -- Default expressions must match
6003 NewD : constant Boolean :=
6004 Present (Expression (New_Discr));
6005 OldD : constant Boolean :=
6006 Present (Expression (Parent (Old_Discr)));
6009 if NewD or OldD then
6011 -- The old default value has been analyzed and expanded,
6012 -- because the current full declaration will have frozen
6013 -- everything before. The new default values have not been
6014 -- expanded, so expand now to check conformance.
6017 Preanalyze_Spec_Expression
6018 (Expression (New_Discr), New_Discr_Type);
6021 if not (NewD and OldD)
6022 or else not Fully_Conformant_Expressions
6023 (Expression (Parent (Old_Discr)),
6024 Expression (New_Discr))
6028 ("default expression for & does not match!",
6035 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6037 if Ada_Version = Ada_83 then
6039 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6042 -- Grouping (use of comma in param lists) must be the same
6043 -- This is where we catch a misconformance like:
6046 -- A : Integer; B : Integer
6048 -- which are represented identically in the tree except
6049 -- for the setting of the flags More_Ids and Prev_Ids.
6051 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6052 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6055 ("grouping of & does not match!", New_Discr_Id);
6061 Next_Discriminant (Old_Discr);
6065 if Present (Old_Discr) then
6066 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6069 elsif Present (New_Discr) then
6071 ("too many discriminants!", Defining_Identifier (New_Discr));
6074 end Check_Discriminant_Conformance;
6076 ----------------------------
6077 -- Check_Fully_Conformant --
6078 ----------------------------
6080 procedure Check_Fully_Conformant
6081 (New_Id : Entity_Id;
6083 Err_Loc : Node_Id := Empty)
6086 pragma Warnings (Off, Result);
6089 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6090 end Check_Fully_Conformant;
6092 --------------------------
6093 -- Check_Limited_Return --
6094 --------------------------
6096 procedure Check_Limited_Return
6102 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6103 -- replaced by anonymous access results. This is an incompatibility with
6104 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6105 -- controllable with special switch. ???
6107 -- A limited interface that is not immutably limited is OK
6109 if Is_Limited_Interface (R_Type)
6111 not (Is_Task_Interface (R_Type)
6112 or else Is_Protected_Interface (R_Type)
6113 or else Is_Synchronized_Interface (R_Type))
6117 elsif Is_Limited_Type (R_Type)
6118 and then not Is_Interface (R_Type)
6119 and then Comes_From_Source (N)
6120 and then not In_Instance_Body
6121 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6123 -- Error in Ada 2005
6125 if Ada_Version >= Ada_2005
6126 and then not Debug_Flag_Dot_L
6127 and then not GNAT_Mode
6130 ("(Ada 2005) cannot copy object of a limited type "
6131 & "(RM-2005 6.5(5.5/2))", Expr);
6133 if Is_Limited_View (R_Type) then
6135 ("\return by reference not permitted in Ada 2005", Expr);
6138 -- Warn in Ada 95 mode, to give folks a heads up about this
6141 -- In GNAT mode, this is just a warning, to allow it to be evilly
6142 -- turned off. Otherwise it is a real error.
6144 -- In a generic context, simplify the warning because it makes no
6145 -- sense to discuss pass-by-reference or copy.
6147 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6148 if Inside_A_Generic then
6150 ("return of limited object not permitted in Ada 2005 "
6151 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6153 elsif Is_Limited_View (R_Type) then
6155 ("return by reference not permitted in Ada 2005 "
6156 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6159 ("cannot copy object of a limited type in Ada 2005 "
6160 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6163 -- Ada 95 mode, and compatibility warnings disabled
6166 pragma Assert (Ada_Version <= Ada_95);
6167 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6168 return; -- skip continuation messages below
6171 if not Inside_A_Generic then
6173 ("\consider switching to return of access type", Expr);
6174 Explain_Limited_Type (R_Type, Expr);
6177 end Check_Limited_Return;
6179 ---------------------------
6180 -- Check_Mode_Conformant --
6181 ---------------------------
6183 procedure Check_Mode_Conformant
6184 (New_Id : Entity_Id;
6186 Err_Loc : Node_Id := Empty;
6187 Get_Inst : Boolean := False)
6190 pragma Warnings (Off, Result);
6193 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6194 end Check_Mode_Conformant;
6196 --------------------------------
6197 -- Check_Overriding_Indicator --
6198 --------------------------------
6200 procedure Check_Overriding_Indicator
6202 Overridden_Subp : Entity_Id;
6203 Is_Primitive : Boolean)
6209 -- No overriding indicator for literals
6211 if Ekind (Subp) = E_Enumeration_Literal then
6214 elsif Ekind (Subp) = E_Entry then
6215 Decl := Parent (Subp);
6217 -- No point in analyzing a malformed operator
6219 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6220 and then Error_Posted (Subp)
6225 Decl := Unit_Declaration_Node (Subp);
6228 if Nkind_In (Decl, N_Subprogram_Body,
6229 N_Subprogram_Body_Stub,
6230 N_Subprogram_Declaration,
6231 N_Abstract_Subprogram_Declaration,
6232 N_Subprogram_Renaming_Declaration)
6234 Spec := Specification (Decl);
6236 elsif Nkind (Decl) = N_Entry_Declaration then
6243 -- The overriding operation is type conformant with the overridden one,
6244 -- but the names of the formals are not required to match. If the names
6245 -- appear permuted in the overriding operation, this is a possible
6246 -- source of confusion that is worth diagnosing. Controlling formals
6247 -- often carry names that reflect the type, and it is not worthwhile
6248 -- requiring that their names match.
6250 if Present (Overridden_Subp)
6251 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6258 Form1 := First_Formal (Subp);
6259 Form2 := First_Formal (Overridden_Subp);
6261 -- If the overriding operation is a synchronized operation, skip
6262 -- the first parameter of the overridden operation, which is
6263 -- implicit in the new one. If the operation is declared in the
6264 -- body it is not primitive and all formals must match.
6266 if Is_Concurrent_Type (Scope (Subp))
6267 and then Is_Tagged_Type (Scope (Subp))
6268 and then not Has_Completion (Scope (Subp))
6270 Form2 := Next_Formal (Form2);
6273 if Present (Form1) then
6274 Form1 := Next_Formal (Form1);
6275 Form2 := Next_Formal (Form2);
6278 while Present (Form1) loop
6279 if not Is_Controlling_Formal (Form1)
6280 and then Present (Next_Formal (Form2))
6281 and then Chars (Form1) = Chars (Next_Formal (Form2))
6283 Error_Msg_Node_2 := Alias (Overridden_Subp);
6284 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6286 ("& does not match corresponding formal of&#",
6291 Next_Formal (Form1);
6292 Next_Formal (Form2);
6297 -- If there is an overridden subprogram, then check that there is no
6298 -- "not overriding" indicator, and mark the subprogram as overriding.
6299 -- This is not done if the overridden subprogram is marked as hidden,
6300 -- which can occur for the case of inherited controlled operations
6301 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6302 -- subprogram is not itself hidden. (Note: This condition could probably
6303 -- be simplified, leaving out the testing for the specific controlled
6304 -- cases, but it seems safer and clearer this way, and echoes similar
6305 -- special-case tests of this kind in other places.)
6307 if Present (Overridden_Subp)
6308 and then (not Is_Hidden (Overridden_Subp)
6310 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6313 and then Present (Alias (Overridden_Subp))
6314 and then not Is_Hidden (Alias (Overridden_Subp))))
6316 if Must_Not_Override (Spec) then
6317 Error_Msg_Sloc := Sloc (Overridden_Subp);
6319 if Ekind (Subp) = E_Entry then
6321 ("entry & overrides inherited operation #", Spec, Subp);
6324 ("subprogram & overrides inherited operation #", Spec, Subp);
6327 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6328 -- as an extension of Root_Controlled, and thus has a useless Adjust
6329 -- operation. This operation should not be inherited by other limited
6330 -- controlled types. An explicit Adjust for them is not overriding.
6332 elsif Must_Override (Spec)
6333 and then Chars (Overridden_Subp) = Name_Adjust
6334 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6335 and then Present (Alias (Overridden_Subp))
6336 and then In_Predefined_Unit (Alias (Overridden_Subp))
6339 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6340 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6342 elsif Is_Subprogram (Subp) then
6343 if Is_Init_Proc (Subp) then
6346 elsif No (Overridden_Operation (Subp)) then
6348 -- For entities generated by Derive_Subprograms the overridden
6349 -- operation is the inherited primitive (which is available
6350 -- through the attribute alias)
6352 if (Is_Dispatching_Operation (Subp)
6353 or else Is_Dispatching_Operation (Overridden_Subp))
6354 and then not Comes_From_Source (Overridden_Subp)
6355 and then Find_Dispatching_Type (Overridden_Subp) =
6356 Find_Dispatching_Type (Subp)
6357 and then Present (Alias (Overridden_Subp))
6358 and then Comes_From_Source (Alias (Overridden_Subp))
6360 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6361 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6364 Set_Overridden_Operation (Subp, Overridden_Subp);
6365 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6370 -- If primitive flag is set or this is a protected operation, then
6371 -- the operation is overriding at the point of its declaration, so
6372 -- warn if necessary. Otherwise it may have been declared before the
6373 -- operation it overrides and no check is required.
6376 and then not Must_Override (Spec)
6377 and then (Is_Primitive
6378 or else Ekind (Scope (Subp)) = E_Protected_Type)
6380 Style.Missing_Overriding (Decl, Subp);
6383 -- If Subp is an operator, it may override a predefined operation, if
6384 -- it is defined in the same scope as the type to which it applies.
6385 -- In that case Overridden_Subp is empty because of our implicit
6386 -- representation for predefined operators. We have to check whether the
6387 -- signature of Subp matches that of a predefined operator. Note that
6388 -- first argument provides the name of the operator, and the second
6389 -- argument the signature that may match that of a standard operation.
6390 -- If the indicator is overriding, then the operator must match a
6391 -- predefined signature, because we know already that there is no
6392 -- explicit overridden operation.
6394 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6395 if Must_Not_Override (Spec) then
6397 -- If this is not a primitive or a protected subprogram, then
6398 -- "not overriding" is illegal.
6401 and then Ekind (Scope (Subp)) /= E_Protected_Type
6403 Error_Msg_N ("overriding indicator only allowed "
6404 & "if subprogram is primitive", Subp);
6406 elsif Can_Override_Operator (Subp) then
6408 ("subprogram& overrides predefined operator ", Spec, Subp);
6411 elsif Must_Override (Spec) then
6412 if No (Overridden_Operation (Subp))
6413 and then not Can_Override_Operator (Subp)
6415 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6418 elsif not Error_Posted (Subp)
6419 and then Style_Check
6420 and then Can_Override_Operator (Subp)
6421 and then not In_Predefined_Unit (Subp)
6423 -- If style checks are enabled, indicate that the indicator is
6424 -- missing. However, at the point of declaration, the type of
6425 -- which this is a primitive operation may be private, in which
6426 -- case the indicator would be premature.
6428 if Has_Private_Declaration (Etype (Subp))
6429 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6433 Style.Missing_Overriding (Decl, Subp);
6437 elsif Must_Override (Spec) then
6438 if Ekind (Subp) = E_Entry then
6439 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6441 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6444 -- If the operation is marked "not overriding" and it's not primitive
6445 -- then an error is issued, unless this is an operation of a task or
6446 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6447 -- has been specified have already been checked above.
6449 elsif Must_Not_Override (Spec)
6450 and then not Is_Primitive
6451 and then Ekind (Subp) /= E_Entry
6452 and then Ekind (Scope (Subp)) /= E_Protected_Type
6455 ("overriding indicator only allowed if subprogram is primitive",
6459 end Check_Overriding_Indicator;
6465 -- Note: this procedure needs to know far too much about how the expander
6466 -- messes with exceptions. The use of the flag Exception_Junk and the
6467 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6468 -- works, but is not very clean. It would be better if the expansion
6469 -- routines would leave Original_Node working nicely, and we could use
6470 -- Original_Node here to ignore all the peculiar expander messing ???
6472 procedure Check_Returns
6476 Proc : Entity_Id := Empty)
6480 procedure Check_Statement_Sequence (L : List_Id);
6481 -- Internal recursive procedure to check a list of statements for proper
6482 -- termination by a return statement (or a transfer of control or a
6483 -- compound statement that is itself internally properly terminated).
6485 ------------------------------
6486 -- Check_Statement_Sequence --
6487 ------------------------------
6489 procedure Check_Statement_Sequence (L : List_Id) is
6494 function Assert_False return Boolean;
6495 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6496 -- rewritten as a null statement when assertions are off. The assert
6497 -- is not active, but it is still enough to kill the warning.
6503 function Assert_False return Boolean is
6504 Orig : constant Node_Id := Original_Node (Last_Stm);
6507 if Nkind (Orig) = N_Pragma
6508 and then Pragma_Name (Orig) = Name_Assert
6509 and then not Error_Posted (Orig)
6512 Arg : constant Node_Id :=
6513 First (Pragma_Argument_Associations (Orig));
6514 Exp : constant Node_Id := Expression (Arg);
6516 return Nkind (Exp) = N_Identifier
6517 and then Chars (Exp) = Name_False;
6527 Raise_Exception_Call : Boolean;
6528 -- Set True if statement sequence terminated by Raise_Exception call
6529 -- or a Reraise_Occurrence call.
6531 -- Start of processing for Check_Statement_Sequence
6534 Raise_Exception_Call := False;
6536 -- Get last real statement
6538 Last_Stm := Last (L);
6540 -- Deal with digging out exception handler statement sequences that
6541 -- have been transformed by the local raise to goto optimization.
6542 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6543 -- optimization has occurred, we are looking at something like:
6546 -- original stmts in block
6550 -- goto L1; | omitted if No_Exception_Propagation
6555 -- goto L3; -- skip handler when exception not raised
6557 -- <<L1>> -- target label for local exception
6571 -- and what we have to do is to dig out the estmts1 and estmts2
6572 -- sequences (which were the original sequences of statements in
6573 -- the exception handlers) and check them.
6575 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6580 exit when Nkind (Stm) /= N_Block_Statement;
6581 exit when not Exception_Junk (Stm);
6584 exit when Nkind (Stm) /= N_Label;
6585 exit when not Exception_Junk (Stm);
6586 Check_Statement_Sequence
6587 (Statements (Handled_Statement_Sequence (Next (Stm))));
6592 exit when Nkind (Stm) /= N_Goto_Statement;
6593 exit when not Exception_Junk (Stm);
6597 -- Don't count pragmas
6599 while Nkind (Last_Stm) = N_Pragma
6601 -- Don't count call to SS_Release (can happen after Raise_Exception)
6604 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6606 Nkind (Name (Last_Stm)) = N_Identifier
6608 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6610 -- Don't count exception junk
6613 (Nkind_In (Last_Stm, N_Goto_Statement,
6615 N_Object_Declaration)
6616 and then Exception_Junk (Last_Stm))
6617 or else Nkind (Last_Stm) in N_Push_xxx_Label
6618 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6620 -- Inserted code, such as finalization calls, is irrelevant: we only
6621 -- need to check original source.
6623 or else Is_Rewrite_Insertion (Last_Stm)
6628 -- Here we have the "real" last statement
6630 Kind := Nkind (Last_Stm);
6632 -- Transfer of control, OK. Note that in the No_Return procedure
6633 -- case, we already diagnosed any explicit return statements, so
6634 -- we can treat them as OK in this context.
6636 if Is_Transfer (Last_Stm) then
6639 -- Check cases of explicit non-indirect procedure calls
6641 elsif Kind = N_Procedure_Call_Statement
6642 and then Is_Entity_Name (Name (Last_Stm))
6644 -- Check call to Raise_Exception procedure which is treated
6645 -- specially, as is a call to Reraise_Occurrence.
6647 -- We suppress the warning in these cases since it is likely that
6648 -- the programmer really does not expect to deal with the case
6649 -- of Null_Occurrence, and thus would find a warning about a
6650 -- missing return curious, and raising Program_Error does not
6651 -- seem such a bad behavior if this does occur.
6653 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6654 -- behavior will be to raise Constraint_Error (see AI-329).
6656 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6658 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6660 Raise_Exception_Call := True;
6662 -- For Raise_Exception call, test first argument, if it is
6663 -- an attribute reference for a 'Identity call, then we know
6664 -- that the call cannot possibly return.
6667 Arg : constant Node_Id :=
6668 Original_Node (First_Actual (Last_Stm));
6670 if Nkind (Arg) = N_Attribute_Reference
6671 and then Attribute_Name (Arg) = Name_Identity
6678 -- If statement, need to look inside if there is an else and check
6679 -- each constituent statement sequence for proper termination.
6681 elsif Kind = N_If_Statement
6682 and then Present (Else_Statements (Last_Stm))
6684 Check_Statement_Sequence (Then_Statements (Last_Stm));
6685 Check_Statement_Sequence (Else_Statements (Last_Stm));
6687 if Present (Elsif_Parts (Last_Stm)) then
6689 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6692 while Present (Elsif_Part) loop
6693 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6701 -- Case statement, check each case for proper termination
6703 elsif Kind = N_Case_Statement then
6707 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6708 while Present (Case_Alt) loop
6709 Check_Statement_Sequence (Statements (Case_Alt));
6710 Next_Non_Pragma (Case_Alt);
6716 -- Block statement, check its handled sequence of statements
6718 elsif Kind = N_Block_Statement then
6724 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6733 -- Loop statement. If there is an iteration scheme, we can definitely
6734 -- fall out of the loop. Similarly if there is an exit statement, we
6735 -- can fall out. In either case we need a following return.
6737 elsif Kind = N_Loop_Statement then
6738 if Present (Iteration_Scheme (Last_Stm))
6739 or else Has_Exit (Entity (Identifier (Last_Stm)))
6743 -- A loop with no exit statement or iteration scheme is either
6744 -- an infinite loop, or it has some other exit (raise/return).
6745 -- In either case, no warning is required.
6751 -- Timed entry call, check entry call and delay alternatives
6753 -- Note: in expanded code, the timed entry call has been converted
6754 -- to a set of expanded statements on which the check will work
6755 -- correctly in any case.
6757 elsif Kind = N_Timed_Entry_Call then
6759 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6760 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6763 -- If statement sequence of entry call alternative is missing,
6764 -- then we can definitely fall through, and we post the error
6765 -- message on the entry call alternative itself.
6767 if No (Statements (ECA)) then
6770 -- If statement sequence of delay alternative is missing, then
6771 -- we can definitely fall through, and we post the error
6772 -- message on the delay alternative itself.
6774 -- Note: if both ECA and DCA are missing the return, then we
6775 -- post only one message, should be enough to fix the bugs.
6776 -- If not we will get a message next time on the DCA when the
6779 elsif No (Statements (DCA)) then
6782 -- Else check both statement sequences
6785 Check_Statement_Sequence (Statements (ECA));
6786 Check_Statement_Sequence (Statements (DCA));
6791 -- Conditional entry call, check entry call and else part
6793 -- Note: in expanded code, the conditional entry call has been
6794 -- converted to a set of expanded statements on which the check
6795 -- will work correctly in any case.
6797 elsif Kind = N_Conditional_Entry_Call then
6799 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6802 -- If statement sequence of entry call alternative is missing,
6803 -- then we can definitely fall through, and we post the error
6804 -- message on the entry call alternative itself.
6806 if No (Statements (ECA)) then
6809 -- Else check statement sequence and else part
6812 Check_Statement_Sequence (Statements (ECA));
6813 Check_Statement_Sequence (Else_Statements (Last_Stm));
6819 -- If we fall through, issue appropriate message
6823 -- Kill warning if last statement is a raise exception call,
6824 -- or a pragma Assert (False). Note that with assertions enabled,
6825 -- such a pragma has been converted into a raise exception call
6826 -- already, so the Assert_False is for the assertions off case.
6828 if not Raise_Exception_Call and then not Assert_False then
6830 -- In GNATprove mode, it is an error to have a missing return
6832 Error_Msg_Warn := SPARK_Mode /= On;
6834 -- Issue error message or warning
6837 ("RETURN statement missing following this statement<<!",
6840 ("\Program_Error ]<<!", Last_Stm);
6843 -- Note: we set Err even though we have not issued a warning
6844 -- because we still have a case of a missing return. This is
6845 -- an extremely marginal case, probably will never be noticed
6846 -- but we might as well get it right.
6850 -- Otherwise we have the case of a procedure marked No_Return
6853 if not Raise_Exception_Call then
6854 if GNATprove_Mode then
6856 ("implied return after this statement would have raised "
6857 & "Program_Error", Last_Stm);
6859 -- In normal compilation mode, do not warn on a generated call
6860 -- (e.g. in the body of a renaming as completion).
6862 elsif Comes_From_Source (Last_Stm) then
6864 ("implied return after this statement will raise "
6865 & "Program_Error??", Last_Stm);
6868 Error_Msg_Warn := SPARK_Mode /= On;
6870 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6874 RE : constant Node_Id :=
6875 Make_Raise_Program_Error (Sloc (Last_Stm),
6876 Reason => PE_Implicit_Return);
6878 Insert_After (Last_Stm, RE);
6882 end Check_Statement_Sequence;
6884 -- Start of processing for Check_Returns
6888 Check_Statement_Sequence (Statements (HSS));
6890 if Present (Exception_Handlers (HSS)) then
6891 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6892 while Present (Handler) loop
6893 Check_Statement_Sequence (Statements (Handler));
6894 Next_Non_Pragma (Handler);
6899 ----------------------------
6900 -- Check_Subprogram_Order --
6901 ----------------------------
6903 procedure Check_Subprogram_Order (N : Node_Id) is
6905 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6906 -- This is used to check if S1 > S2 in the sense required by this test,
6907 -- for example nameab < namec, but name2 < name10.
6909 -----------------------------
6910 -- Subprogram_Name_Greater --
6911 -----------------------------
6913 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6918 -- Deal with special case where names are identical except for a
6919 -- numerical suffix. These are handled specially, taking the numeric
6920 -- ordering from the suffix into account.
6923 while S1 (L1) in '0' .. '9' loop
6928 while S2 (L2) in '0' .. '9' loop
6932 -- If non-numeric parts non-equal, do straight compare
6934 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6937 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6938 -- that a missing suffix is treated as numeric zero in this test.
6942 while L1 < S1'Last loop
6944 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6948 while L2 < S2'Last loop
6950 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6955 end Subprogram_Name_Greater;
6957 -- Start of processing for Check_Subprogram_Order
6960 -- Check body in alpha order if this is option
6963 and then Style_Check_Order_Subprograms
6964 and then Nkind (N) = N_Subprogram_Body
6965 and then Comes_From_Source (N)
6966 and then In_Extended_Main_Source_Unit (N)
6970 renames Scope_Stack.Table
6971 (Scope_Stack.Last).Last_Subprogram_Name;
6973 Body_Id : constant Entity_Id :=
6974 Defining_Entity (Specification (N));
6977 Get_Decoded_Name_String (Chars (Body_Id));
6980 if Subprogram_Name_Greater
6981 (LSN.all, Name_Buffer (1 .. Name_Len))
6983 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6989 LSN := new String'(Name_Buffer (1 .. Name_Len));
6992 end Check_Subprogram_Order;
6994 ------------------------------
6995 -- Check_Subtype_Conformant --
6996 ------------------------------
6998 procedure Check_Subtype_Conformant
6999 (New_Id : Entity_Id;
7001 Err_Loc : Node_Id := Empty;
7002 Skip_Controlling_Formals : Boolean := False;
7003 Get_Inst : Boolean := False)
7006 pragma Warnings (Off, Result);
7009 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7010 Skip_Controlling_Formals => Skip_Controlling_Formals,
7011 Get_Inst => Get_Inst);
7012 end Check_Subtype_Conformant;
7014 -----------------------------------
7015 -- Check_Synchronized_Overriding --
7016 -----------------------------------
7018 procedure Check_Synchronized_Overriding
7019 (Def_Id : Entity_Id;
7020 Overridden_Subp : out Entity_Id)
7022 Ifaces_List : Elist_Id;
7026 function Matches_Prefixed_View_Profile
7027 (Prim_Params : List_Id;
7028 Iface_Params : List_Id) return Boolean;
7029 -- Determine whether a subprogram's parameter profile Prim_Params
7030 -- matches that of a potentially overridden interface subprogram
7031 -- Iface_Params. Also determine if the type of first parameter of
7032 -- Iface_Params is an implemented interface.
7034 -----------------------------------
7035 -- Matches_Prefixed_View_Profile --
7036 -----------------------------------
7038 function Matches_Prefixed_View_Profile
7039 (Prim_Params : List_Id;
7040 Iface_Params : List_Id) return Boolean
7042 function Is_Implemented
7043 (Ifaces_List : Elist_Id;
7044 Iface : Entity_Id) return Boolean;
7045 -- Determine if Iface is implemented by the current task or
7048 --------------------
7049 -- Is_Implemented --
7050 --------------------
7052 function Is_Implemented
7053 (Ifaces_List : Elist_Id;
7054 Iface : Entity_Id) return Boolean
7056 Iface_Elmt : Elmt_Id;
7059 Iface_Elmt := First_Elmt (Ifaces_List);
7060 while Present (Iface_Elmt) loop
7061 if Node (Iface_Elmt) = Iface then
7065 Next_Elmt (Iface_Elmt);
7073 Iface_Id : Entity_Id;
7074 Iface_Param : Node_Id;
7075 Iface_Typ : Entity_Id;
7076 Prim_Id : Entity_Id;
7077 Prim_Param : Node_Id;
7078 Prim_Typ : Entity_Id;
7080 -- Start of processing for Matches_Prefixed_View_Profile
7083 Iface_Param := First (Iface_Params);
7084 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7086 if Is_Access_Type (Iface_Typ) then
7087 Iface_Typ := Designated_Type (Iface_Typ);
7090 Prim_Param := First (Prim_Params);
7092 -- The first parameter of the potentially overridden subprogram must
7093 -- be an interface implemented by Prim.
7095 if not Is_Interface (Iface_Typ)
7096 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7101 -- The checks on the object parameters are done, so move on to the
7102 -- rest of the parameters.
7104 if not In_Scope then
7105 Prim_Param := Next (Prim_Param);
7108 Iface_Param := Next (Iface_Param);
7109 while Present (Iface_Param) and then Present (Prim_Param) loop
7110 Iface_Id := Defining_Identifier (Iface_Param);
7111 Iface_Typ := Find_Parameter_Type (Iface_Param);
7113 Prim_Id := Defining_Identifier (Prim_Param);
7114 Prim_Typ := Find_Parameter_Type (Prim_Param);
7116 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7117 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7118 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7120 Iface_Typ := Designated_Type (Iface_Typ);
7121 Prim_Typ := Designated_Type (Prim_Typ);
7124 -- Case of multiple interface types inside a parameter profile
7126 -- (Obj_Param : in out Iface; ...; Param : Iface)
7128 -- If the interface type is implemented, then the matching type in
7129 -- the primitive should be the implementing record type.
7131 if Ekind (Iface_Typ) = E_Record_Type
7132 and then Is_Interface (Iface_Typ)
7133 and then Is_Implemented (Ifaces_List, Iface_Typ)
7135 if Prim_Typ /= Typ then
7139 -- The two parameters must be both mode and subtype conformant
7141 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7143 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7152 -- One of the two lists contains more parameters than the other
7154 if Present (Iface_Param) or else Present (Prim_Param) then
7159 end Matches_Prefixed_View_Profile;
7161 -- Start of processing for Check_Synchronized_Overriding
7164 Overridden_Subp := Empty;
7166 -- Def_Id must be an entry or a subprogram. We should skip predefined
7167 -- primitives internally generated by the front end; however at this
7168 -- stage predefined primitives are still not fully decorated. As a
7169 -- minor optimization we skip here internally generated subprograms.
7171 if (Ekind (Def_Id) /= E_Entry
7172 and then Ekind (Def_Id) /= E_Function
7173 and then Ekind (Def_Id) /= E_Procedure)
7174 or else not Comes_From_Source (Def_Id)
7179 -- Search for the concurrent declaration since it contains the list of
7180 -- all implemented interfaces. In this case, the subprogram is declared
7181 -- within the scope of a protected or a task type.
7183 if Present (Scope (Def_Id))
7184 and then Is_Concurrent_Type (Scope (Def_Id))
7185 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7187 Typ := Scope (Def_Id);
7190 -- The enclosing scope is not a synchronized type and the subprogram
7193 elsif No (First_Formal (Def_Id)) then
7196 -- The subprogram has formals and hence it may be a primitive of a
7200 Typ := Etype (First_Formal (Def_Id));
7202 if Is_Access_Type (Typ) then
7203 Typ := Directly_Designated_Type (Typ);
7206 if Is_Concurrent_Type (Typ)
7207 and then not Is_Generic_Actual_Type (Typ)
7211 -- This case occurs when the concurrent type is declared within a
7212 -- generic unit. As a result the corresponding record has been built
7213 -- and used as the type of the first formal, we just have to retrieve
7214 -- the corresponding concurrent type.
7216 elsif Is_Concurrent_Record_Type (Typ)
7217 and then not Is_Class_Wide_Type (Typ)
7218 and then Present (Corresponding_Concurrent_Type (Typ))
7220 Typ := Corresponding_Concurrent_Type (Typ);
7228 -- There is no overriding to check if this is an inherited operation in
7229 -- a type derivation for a generic actual.
7231 Collect_Interfaces (Typ, Ifaces_List);
7233 if Is_Empty_Elmt_List (Ifaces_List) then
7237 -- Determine whether entry or subprogram Def_Id overrides a primitive
7238 -- operation that belongs to one of the interfaces in Ifaces_List.
7241 Candidate : Entity_Id := Empty;
7242 Hom : Entity_Id := Empty;
7243 Subp : Entity_Id := Empty;
7246 -- Traverse the homonym chain, looking for a potentially overridden
7247 -- subprogram that belongs to an implemented interface.
7249 Hom := Current_Entity_In_Scope (Def_Id);
7250 while Present (Hom) loop
7254 or else not Is_Overloadable (Subp)
7255 or else not Is_Primitive (Subp)
7256 or else not Is_Dispatching_Operation (Subp)
7257 or else not Present (Find_Dispatching_Type (Subp))
7258 or else not Is_Interface (Find_Dispatching_Type (Subp))
7262 -- Entries and procedures can override abstract or null interface
7265 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7266 and then Ekind (Subp) = E_Procedure
7267 and then Matches_Prefixed_View_Profile
7268 (Parameter_Specifications (Parent (Def_Id)),
7269 Parameter_Specifications (Parent (Subp)))
7273 -- For an overridden subprogram Subp, check whether the mode
7274 -- of its first parameter is correct depending on the kind of
7275 -- synchronized type.
7278 Formal : constant Node_Id := First_Formal (Candidate);
7281 -- In order for an entry or a protected procedure to
7282 -- override, the first parameter of the overridden routine
7283 -- must be of mode "out", "in out", or access-to-variable.
7285 if Ekind_In (Candidate, E_Entry, E_Procedure)
7286 and then Is_Protected_Type (Typ)
7287 and then Ekind (Formal) /= E_In_Out_Parameter
7288 and then Ekind (Formal) /= E_Out_Parameter
7289 and then Nkind (Parameter_Type (Parent (Formal))) /=
7294 -- All other cases are OK since a task entry or routine does
7295 -- not have a restriction on the mode of the first parameter
7296 -- of the overridden interface routine.
7299 Overridden_Subp := Candidate;
7304 -- Functions can override abstract interface functions. Return
7305 -- types must be subtype conformant.
7307 elsif Ekind (Def_Id) = E_Function
7308 and then Ekind (Subp) = E_Function
7309 and then Matches_Prefixed_View_Profile
7310 (Parameter_Specifications (Parent (Def_Id)),
7311 Parameter_Specifications (Parent (Subp)))
7312 and then Conforming_Types
7313 (Etype (Def_Id), Etype (Subp), Subtype_Conformant)
7317 -- If an inherited subprogram is implemented by a protected
7318 -- function, then the first parameter of the inherited
7319 -- subprogram shall be of mode in, but not an access-to-
7320 -- variable parameter (RM 9.4(11/9)).
7322 if Present (First_Formal (Subp))
7323 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7325 (not Is_Access_Type (Etype (First_Formal (Subp)))
7327 Is_Access_Constant (Etype (First_Formal (Subp))))
7329 Overridden_Subp := Subp;
7334 Hom := Homonym (Hom);
7337 -- After examining all candidates for overriding, we are left with
7338 -- the best match, which is a mode-incompatible interface routine.
7340 if In_Scope and then Present (Candidate) then
7341 Error_Msg_PT (Def_Id, Candidate);
7344 Overridden_Subp := Candidate;
7347 end Check_Synchronized_Overriding;
7349 ---------------------------
7350 -- Check_Type_Conformant --
7351 ---------------------------
7353 procedure Check_Type_Conformant
7354 (New_Id : Entity_Id;
7356 Err_Loc : Node_Id := Empty)
7359 pragma Warnings (Off, Result);
7362 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7363 end Check_Type_Conformant;
7365 ---------------------------
7366 -- Can_Override_Operator --
7367 ---------------------------
7369 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7373 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7377 Typ := Base_Type (Etype (First_Formal (Subp)));
7379 -- Check explicitly that the operation is a primitive of the type
7381 return Operator_Matches_Spec (Subp, Subp)
7382 and then not Is_Generic_Type (Typ)
7383 and then Scope (Subp) = Scope (Typ)
7384 and then not Is_Class_Wide_Type (Typ);
7386 end Can_Override_Operator;
7388 ----------------------
7389 -- Conforming_Types --
7390 ----------------------
7392 function Conforming_Types
7395 Ctype : Conformance_Type;
7396 Get_Inst : Boolean := False) return Boolean
7398 function Base_Types_Match
7400 Typ_2 : Entity_Id) return Boolean;
7401 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7402 -- in different scopes (e.g. parent and child instances), then verify
7403 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7404 -- the same subtype chain. The whole purpose of this procedure is to
7405 -- prevent spurious ambiguities in an instantiation that may arise if
7406 -- two distinct generic types are instantiated with the same actual.
7408 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7409 -- An access parameter can designate an incomplete type. If the
7410 -- incomplete type is the limited view of a type from a limited_
7411 -- with_clause, check whether the non-limited view is available.
7412 -- If it is a (non-limited) incomplete type, get the full view.
7414 function Matches_Limited_With_View
7416 Typ_2 : Entity_Id) return Boolean;
7417 -- Returns True if and only if either Typ_1 denotes a limited view of
7418 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7419 -- the limited with view of a type is used in a subprogram declaration
7420 -- and the subprogram body is in the scope of a regular with clause for
7421 -- the same unit. In such a case, the two type entities are considered
7422 -- identical for purposes of conformance checking.
7424 ----------------------
7425 -- Base_Types_Match --
7426 ----------------------
7428 function Base_Types_Match
7430 Typ_2 : Entity_Id) return Boolean
7432 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7433 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7436 if Typ_1 = Typ_2 then
7439 elsif Base_1 = Base_2 then
7441 -- The following is too permissive. A more precise test should
7442 -- check that the generic actual is an ancestor subtype of the
7445 -- See code in Find_Corresponding_Spec that applies an additional
7446 -- filter to handle accidental amiguities in instances.
7449 not Is_Generic_Actual_Type (Typ_1)
7450 or else not Is_Generic_Actual_Type (Typ_2)
7451 or else Scope (Typ_1) /= Scope (Typ_2);
7453 -- If Typ_2 is a generic actual type it is declared as the subtype of
7454 -- the actual. If that actual is itself a subtype we need to use its
7455 -- own base type to check for compatibility.
7457 elsif Ekind (Base_2) = Ekind (Typ_2)
7458 and then Base_1 = Base_Type (Base_2)
7462 elsif Ekind (Base_1) = Ekind (Typ_1)
7463 and then Base_2 = Base_Type (Base_1)
7470 end Base_Types_Match;
7472 --------------------------
7473 -- Find_Designated_Type --
7474 --------------------------
7476 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7480 Desig := Directly_Designated_Type (Typ);
7482 if Ekind (Desig) = E_Incomplete_Type then
7484 -- If regular incomplete type, get full view if available
7486 if Present (Full_View (Desig)) then
7487 Desig := Full_View (Desig);
7489 -- If limited view of a type, get non-limited view if available,
7490 -- and check again for a regular incomplete type.
7492 elsif Present (Non_Limited_View (Desig)) then
7493 Desig := Get_Full_View (Non_Limited_View (Desig));
7498 end Find_Designated_Type;
7500 -------------------------------
7501 -- Matches_Limited_With_View --
7502 -------------------------------
7504 function Matches_Limited_With_View
7506 Typ_2 : Entity_Id) return Boolean
7508 function Is_Matching_Limited_View
7510 View : Entity_Id) return Boolean;
7511 -- Determine whether non-limited view View denotes type Typ in some
7512 -- conformant fashion.
7514 ------------------------------
7515 -- Is_Matching_Limited_View --
7516 ------------------------------
7518 function Is_Matching_Limited_View
7520 View : Entity_Id) return Boolean
7522 Root_Typ : Entity_Id;
7523 Root_View : Entity_Id;
7526 -- The non-limited view directly denotes the type
7531 -- The type is a subtype of the non-limited view
7533 elsif Is_Subtype_Of (Typ, View) then
7536 -- Both the non-limited view and the type denote class-wide types
7538 elsif Is_Class_Wide_Type (Typ)
7539 and then Is_Class_Wide_Type (View)
7541 Root_Typ := Root_Type (Typ);
7542 Root_View := Root_Type (View);
7544 if Root_Typ = Root_View then
7547 -- An incomplete tagged type and its full view may receive two
7548 -- distinct class-wide types when the related package has not
7549 -- been analyzed yet.
7552 -- type T is tagged; -- CW_1
7553 -- type T is tagged null record; -- CW_2
7556 -- This is because the package lacks any semantic information
7557 -- that may eventually link both views of T. As a consequence,
7558 -- a client of the limited view of Pack will see CW_2 while a
7559 -- client of the non-limited view of Pack will see CW_1.
7561 elsif Is_Incomplete_Type (Root_Typ)
7562 and then Present (Full_View (Root_Typ))
7563 and then Full_View (Root_Typ) = Root_View
7567 elsif Is_Incomplete_Type (Root_View)
7568 and then Present (Full_View (Root_View))
7569 and then Full_View (Root_View) = Root_Typ
7576 end Is_Matching_Limited_View;
7578 -- Start of processing for Matches_Limited_With_View
7581 -- In some cases a type imported through a limited_with clause, and
7582 -- its non-limited view are both visible, for example in an anonymous
7583 -- access-to-class-wide type in a formal, or when building the body
7584 -- for a subprogram renaming after the subprogram has been frozen.
7585 -- In these cases both entities designate the same type. In addition,
7586 -- if one of them is an actual in an instance, it may be a subtype of
7587 -- the non-limited view of the other.
7589 if From_Limited_With (Typ_1)
7590 and then From_Limited_With (Typ_2)
7591 and then Available_View (Typ_1) = Available_View (Typ_2)
7595 elsif From_Limited_With (Typ_1) then
7596 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7598 elsif From_Limited_With (Typ_2) then
7599 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7604 end Matches_Limited_With_View;
7608 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7610 Type_1 : Entity_Id := T1;
7611 Type_2 : Entity_Id := T2;
7613 -- Start of processing for Conforming_Types
7616 -- The context is an instance association for a formal access-to-
7617 -- subprogram type; the formal parameter types require mapping because
7618 -- they may denote other formal parameters of the generic unit.
7621 Type_1 := Get_Instance_Of (T1);
7622 Type_2 := Get_Instance_Of (T2);
7625 -- If one of the types is a view of the other introduced by a limited
7626 -- with clause, treat these as conforming for all purposes.
7628 if Matches_Limited_With_View (T1, T2) then
7631 elsif Base_Types_Match (Type_1, Type_2) then
7632 if Ctype <= Mode_Conformant then
7637 Subtypes_Statically_Match (Type_1, Type_2)
7638 and then Dimensions_Match (Type_1, Type_2);
7641 elsif Is_Incomplete_Or_Private_Type (Type_1)
7642 and then Present (Full_View (Type_1))
7643 and then Base_Types_Match (Full_View (Type_1), Type_2)
7646 Ctype <= Mode_Conformant
7647 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7649 elsif Ekind (Type_2) = E_Incomplete_Type
7650 and then Present (Full_View (Type_2))
7651 and then Base_Types_Match (Type_1, Full_View (Type_2))
7654 Ctype <= Mode_Conformant
7655 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7657 elsif Is_Private_Type (Type_2)
7658 and then In_Instance
7659 and then Present (Full_View (Type_2))
7660 and then Base_Types_Match (Type_1, Full_View (Type_2))
7663 Ctype <= Mode_Conformant
7664 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7666 -- Another confusion between views in a nested instance with an
7667 -- actual private type whose full view is not in scope.
7669 elsif Ekind (Type_2) = E_Private_Subtype
7670 and then In_Instance
7671 and then Etype (Type_2) = Type_1
7675 -- In Ada 2012, incomplete types (including limited views) can appear
7676 -- as actuals in instantiations, where they are conformant to the
7677 -- corresponding incomplete formal.
7679 elsif Is_Incomplete_Type (Type_1)
7680 and then Is_Incomplete_Type (Type_2)
7681 and then In_Instance
7682 and then (Used_As_Generic_Actual (Type_1)
7683 or else Used_As_Generic_Actual (Type_2))
7688 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7689 -- treated recursively because they carry a signature. As far as
7690 -- conformance is concerned, convention plays no role, and either
7691 -- or both could be access to protected subprograms.
7693 Are_Anonymous_Access_To_Subprogram_Types :=
7694 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7695 E_Anonymous_Access_Protected_Subprogram_Type)
7697 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7698 E_Anonymous_Access_Protected_Subprogram_Type);
7700 -- Test anonymous access type case. For this case, static subtype
7701 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7702 -- the base types because we may have built internal subtype entities
7703 -- to handle null-excluding types (see Process_Formals).
7705 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7707 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7709 -- Ada 2005 (AI-254)
7711 or else Are_Anonymous_Access_To_Subprogram_Types
7714 Desig_1 : Entity_Id;
7715 Desig_2 : Entity_Id;
7718 -- In Ada 2005, access constant indicators must match for
7719 -- subtype conformance.
7721 if Ada_Version >= Ada_2005
7722 and then Ctype >= Subtype_Conformant
7724 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7729 Desig_1 := Find_Designated_Type (Type_1);
7730 Desig_2 := Find_Designated_Type (Type_2);
7732 -- If the context is an instance association for a formal
7733 -- access-to-subprogram type; formal access parameter designated
7734 -- types require mapping because they may denote other formal
7735 -- parameters of the generic unit.
7738 Desig_1 := Get_Instance_Of (Desig_1);
7739 Desig_2 := Get_Instance_Of (Desig_2);
7742 -- It is possible for a Class_Wide_Type to be introduced for an
7743 -- incomplete type, in which case there is a separate class_ wide
7744 -- type for the full view. The types conform if their Etypes
7745 -- conform, i.e. one may be the full view of the other. This can
7746 -- only happen in the context of an access parameter, other uses
7747 -- of an incomplete Class_Wide_Type are illegal.
7749 if Is_Class_Wide_Type (Desig_1)
7751 Is_Class_Wide_Type (Desig_2)
7755 (Etype (Base_Type (Desig_1)),
7756 Etype (Base_Type (Desig_2)), Ctype);
7758 elsif Are_Anonymous_Access_To_Subprogram_Types then
7759 if Ada_Version < Ada_2005 then
7761 Ctype = Type_Conformant
7762 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7764 -- We must check the conformance of the signatures themselves
7768 Conformant : Boolean;
7771 (Desig_1, Desig_2, Ctype, False, Conformant);
7776 -- A limited view of an actual matches the corresponding
7777 -- incomplete formal.
7779 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7780 and then From_Limited_With (Desig_2)
7781 and then Used_As_Generic_Actual (Etype (Desig_2))
7786 return Base_Type (Desig_1) = Base_Type (Desig_2)
7787 and then (Ctype = Type_Conformant
7789 Subtypes_Statically_Match (Desig_1, Desig_2));
7793 -- Otherwise definitely no match
7796 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7797 and then Is_Access_Type (Type_2))
7798 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7799 and then Is_Access_Type (Type_1)))
7802 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7804 May_Hide_Profile := True;
7809 end Conforming_Types;
7811 --------------------------
7812 -- Create_Extra_Formals --
7813 --------------------------
7815 procedure Create_Extra_Formals (E : Entity_Id) is
7816 First_Extra : Entity_Id := Empty;
7818 Last_Extra : Entity_Id := Empty;
7820 function Add_Extra_Formal
7821 (Assoc_Entity : Entity_Id;
7824 Suffix : String) return Entity_Id;
7825 -- Add an extra formal to the current list of formals and extra formals.
7826 -- The extra formal is added to the end of the list of extra formals,
7827 -- and also returned as the result. These formals are always of mode IN.
7828 -- The new formal has the type Typ, is declared in Scope, and its name
7829 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7830 -- The following suffixes are currently used. They should not be changed
7831 -- without coordinating with CodePeer, which makes use of these to
7832 -- provide better messages.
7834 -- O denotes the Constrained bit.
7835 -- L denotes the accessibility level.
7836 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7837 -- the full list in exp_ch6.BIP_Formal_Kind.
7839 ----------------------
7840 -- Add_Extra_Formal --
7841 ----------------------
7843 function Add_Extra_Formal
7844 (Assoc_Entity : Entity_Id;
7847 Suffix : String) return Entity_Id
7849 EF : constant Entity_Id :=
7850 Make_Defining_Identifier (Sloc (Assoc_Entity),
7851 Chars => New_External_Name (Chars (Assoc_Entity),
7855 -- A little optimization. Never generate an extra formal for the
7856 -- _init operand of an initialization procedure, since it could
7859 if Chars (Formal) = Name_uInit then
7863 Set_Ekind (EF, E_In_Parameter);
7864 Set_Actual_Subtype (EF, Typ);
7865 Set_Etype (EF, Typ);
7866 Set_Scope (EF, Scope);
7867 Set_Mechanism (EF, Default_Mechanism);
7868 Set_Formal_Validity (EF);
7870 if No (First_Extra) then
7872 Set_Extra_Formals (Scope, EF);
7875 if Present (Last_Extra) then
7876 Set_Extra_Formal (Last_Extra, EF);
7882 end Add_Extra_Formal;
7886 Formal_Type : Entity_Id;
7887 P_Formal : Entity_Id := Empty;
7889 -- Start of processing for Create_Extra_Formals
7892 -- We never generate extra formals if expansion is not active because we
7893 -- don't need them unless we are generating code.
7895 if not Expander_Active then
7899 -- No need to generate extra formals in interface thunks whose target
7900 -- primitive has no extra formals.
7902 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7906 -- If this is a derived subprogram then the subtypes of the parent
7907 -- subprogram's formal parameters will be used to determine the need
7908 -- for extra formals.
7910 if Is_Overloadable (E) and then Present (Alias (E)) then
7911 P_Formal := First_Formal (Alias (E));
7914 Formal := First_Formal (E);
7915 while Present (Formal) loop
7916 Last_Extra := Formal;
7917 Next_Formal (Formal);
7920 -- If Extra_Formals were already created, don't do it again. This
7921 -- situation may arise for subprogram types created as part of
7922 -- dispatching calls (see Expand_Dispatching_Call).
7924 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7928 -- If the subprogram is a predefined dispatching subprogram then don't
7929 -- generate any extra constrained or accessibility level formals. In
7930 -- general we suppress these for internal subprograms (by not calling
7931 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7932 -- generated stream attributes do get passed through because extra
7933 -- build-in-place formals are needed in some cases (limited 'Input).
7935 if Is_Predefined_Internal_Operation (E) then
7936 goto Test_For_Func_Result_Extras;
7939 Formal := First_Formal (E);
7940 while Present (Formal) loop
7942 -- Create extra formal for supporting the attribute 'Constrained.
7943 -- The case of a private type view without discriminants also
7944 -- requires the extra formal if the underlying type has defaulted
7947 if Ekind (Formal) /= E_In_Parameter then
7948 if Present (P_Formal) then
7949 Formal_Type := Etype (P_Formal);
7951 Formal_Type := Etype (Formal);
7954 -- Do not produce extra formals for Unchecked_Union parameters.
7955 -- Jump directly to the end of the loop.
7957 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7958 goto Skip_Extra_Formal_Generation;
7961 if not Has_Discriminants (Formal_Type)
7962 and then Ekind (Formal_Type) in Private_Kind
7963 and then Present (Underlying_Type (Formal_Type))
7965 Formal_Type := Underlying_Type (Formal_Type);
7968 -- Suppress the extra formal if formal's subtype is constrained or
7969 -- indefinite, or we're compiling for Ada 2012 and the underlying
7970 -- type is tagged and limited. In Ada 2012, a limited tagged type
7971 -- can have defaulted discriminants, but 'Constrained is required
7972 -- to return True, so the formal is never needed (see AI05-0214).
7973 -- Note that this ensures consistency of calling sequences for
7974 -- dispatching operations when some types in a class have defaults
7975 -- on discriminants and others do not (and requiring the extra
7976 -- formal would introduce distributed overhead).
7978 -- If the type does not have a completion yet, treat as prior to
7979 -- Ada 2012 for consistency.
7981 if Has_Discriminants (Formal_Type)
7982 and then not Is_Constrained (Formal_Type)
7983 and then Is_Definite_Subtype (Formal_Type)
7984 and then (Ada_Version < Ada_2012
7985 or else No (Underlying_Type (Formal_Type))
7987 (Is_Limited_Type (Formal_Type)
7990 (Underlying_Type (Formal_Type)))))
7992 Set_Extra_Constrained
7993 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7997 -- Create extra formal for supporting accessibility checking. This
7998 -- is done for both anonymous access formals and formals of named
7999 -- access types that are marked as controlling formals. The latter
8000 -- case can occur when Expand_Dispatching_Call creates a subprogram
8001 -- type and substitutes the types of access-to-class-wide actuals
8002 -- for the anonymous access-to-specific-type of controlling formals.
8003 -- Base_Type is applied because in cases where there is a null
8004 -- exclusion the formal may have an access subtype.
8006 -- This is suppressed if we specifically suppress accessibility
8007 -- checks at the package level for either the subprogram, or the
8008 -- package in which it resides. However, we do not suppress it
8009 -- simply if the scope has accessibility checks suppressed, since
8010 -- this could cause trouble when clients are compiled with a
8011 -- different suppression setting. The explicit checks at the
8012 -- package level are safe from this point of view.
8014 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8015 or else (Is_Controlling_Formal (Formal)
8016 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8018 (Explicit_Suppress (E, Accessibility_Check)
8020 Explicit_Suppress (Scope (E), Accessibility_Check))
8023 or else Present (Extra_Accessibility (P_Formal)))
8025 Set_Extra_Accessibility
8026 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8029 -- This label is required when skipping extra formal generation for
8030 -- Unchecked_Union parameters.
8032 <<Skip_Extra_Formal_Generation>>
8034 if Present (P_Formal) then
8035 Next_Formal (P_Formal);
8038 Next_Formal (Formal);
8041 <<Test_For_Func_Result_Extras>>
8043 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8044 -- function call is ... determined by the point of call ...".
8046 if Needs_Result_Accessibility_Level (E) then
8047 Set_Extra_Accessibility_Of_Result
8048 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8051 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8052 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8054 if Is_Build_In_Place_Function (E) then
8056 Result_Subt : constant Entity_Id := Etype (E);
8057 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8058 Formal_Typ : Entity_Id;
8059 Subp_Decl : Node_Id;
8060 Discard : Entity_Id;
8063 -- In the case of functions with unconstrained result subtypes,
8064 -- add a 4-state formal indicating whether the return object is
8065 -- allocated by the caller (1), or should be allocated by the
8066 -- callee on the secondary stack (2), in the global heap (3), or
8067 -- in a user-defined storage pool (4). For the moment we just use
8068 -- Natural for the type of this formal. Note that this formal
8069 -- isn't usually needed in the case where the result subtype is
8070 -- constrained, but it is needed when the function has a tagged
8071 -- result, because generally such functions can be called in a
8072 -- dispatching context and such calls must be handled like calls
8073 -- to a class-wide function.
8075 if Needs_BIP_Alloc_Form (E) then
8078 (E, Standard_Natural,
8079 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8081 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8082 -- use a user-defined pool. This formal is not added on
8083 -- ZFP as those targets do not support pools.
8085 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8088 (E, RTE (RE_Root_Storage_Pool_Ptr),
8089 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8093 -- In the case of functions whose result type needs finalization,
8094 -- add an extra formal which represents the finalization master.
8096 if Needs_BIP_Finalization_Master (E) then
8099 (E, RTE (RE_Finalization_Master_Ptr),
8100 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8103 -- When the result type contains tasks, add two extra formals: the
8104 -- master of the tasks to be created, and the caller's activation
8107 if Has_Task (Full_Subt) then
8110 (E, RTE (RE_Master_Id),
8111 E, BIP_Formal_Suffix (BIP_Task_Master));
8114 (E, RTE (RE_Activation_Chain_Access),
8115 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8118 -- All build-in-place functions get an extra formal that will be
8119 -- passed the address of the return object within the caller.
8122 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8124 -- Incomplete_View_From_Limited_With is needed here because
8125 -- gigi gets confused if the designated type is the full view
8126 -- coming from a limited-with'ed package. In the normal case,
8127 -- (no limited with) Incomplete_View_From_Limited_With
8128 -- returns Result_Subt.
8130 Set_Directly_Designated_Type
8131 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8132 Set_Etype (Formal_Typ, Formal_Typ);
8133 Set_Depends_On_Private
8134 (Formal_Typ, Has_Private_Component (Formal_Typ));
8135 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8136 Set_Is_Access_Constant (Formal_Typ, False);
8138 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8139 -- the designated type comes from the limited view (for back-end
8142 Set_From_Limited_With
8143 (Formal_Typ, From_Limited_With (Result_Subt));
8145 Layout_Type (Formal_Typ);
8147 -- Force the definition of the Itype in case of internal function
8148 -- calls within the same or nested scope.
8150 if Is_Subprogram_Or_Generic_Subprogram (E) then
8151 Subp_Decl := Parent (E);
8153 -- The insertion point for an Itype reference should be after
8154 -- the unit declaration node of the subprogram. An exception
8155 -- to this are inherited operations from a parent type in which
8156 -- case the derived type acts as their parent.
8158 if Nkind_In (Subp_Decl, N_Function_Specification,
8159 N_Procedure_Specification)
8161 Subp_Decl := Parent (Subp_Decl);
8164 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8169 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8173 -- If this is an instance of a generic, we need to have extra formals
8176 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8177 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8179 end Create_Extra_Formals;
8181 -----------------------------
8182 -- Enter_Overloaded_Entity --
8183 -----------------------------
8185 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8186 function Matches_Predefined_Op return Boolean;
8187 -- This returns an approximation of whether S matches a predefined
8188 -- operator, based on the operator symbol, and the parameter and result
8189 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8191 ---------------------------
8192 -- Matches_Predefined_Op --
8193 ---------------------------
8195 function Matches_Predefined_Op return Boolean is
8196 Formal_1 : constant Entity_Id := First_Formal (S);
8197 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8198 Op : constant Name_Id := Chars (S);
8199 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8200 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8205 if Present (Formal_2) then
8207 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8210 -- All but "&" and "**" have same-types parameters
8219 if Type_1 /= Type_2 then
8224 -- Check parameter and result types
8232 Is_Boolean_Type (Result_Type)
8233 and then Result_Type = Type_1;
8239 Is_Integer_Type (Result_Type)
8240 and then Result_Type = Type_1;
8248 Is_Numeric_Type (Result_Type)
8249 and then Result_Type = Type_1;
8255 Is_Boolean_Type (Result_Type)
8256 and then not Is_Limited_Type (Type_1);
8264 Is_Boolean_Type (Result_Type)
8265 and then (Is_Array_Type (Type_1)
8266 or else Is_Scalar_Type (Type_1));
8268 when Name_Op_Concat =>
8269 return Is_Array_Type (Result_Type);
8271 when Name_Op_Expon =>
8273 (Is_Integer_Type (Result_Type)
8274 or else Is_Floating_Point_Type (Result_Type))
8275 and then Result_Type = Type_1
8276 and then Type_2 = Standard_Integer;
8279 raise Program_Error;
8292 Is_Numeric_Type (Result_Type)
8293 and then Result_Type = Type_1;
8297 Is_Boolean_Type (Result_Type)
8298 and then Result_Type = Type_1;
8301 raise Program_Error;
8304 end Matches_Predefined_Op;
8308 E : Entity_Id := Current_Entity_In_Scope (S);
8309 C_E : Entity_Id := Current_Entity (S);
8311 -- Start of processing for Enter_Overloaded_Entity
8315 Set_Has_Homonym (E);
8316 Set_Has_Homonym (S);
8319 Set_Is_Immediately_Visible (S);
8320 Set_Scope (S, Current_Scope);
8322 -- Chain new entity if front of homonym in current scope, so that
8323 -- homonyms are contiguous.
8325 if Present (E) and then E /= C_E then
8326 while Homonym (C_E) /= E loop
8327 C_E := Homonym (C_E);
8330 Set_Homonym (C_E, S);
8334 Set_Current_Entity (S);
8339 if Is_Inherited_Operation (S) then
8340 Append_Inherited_Subprogram (S);
8342 Append_Entity (S, Current_Scope);
8345 Set_Public_Status (S);
8347 if Debug_Flag_E then
8348 Write_Str ("New overloaded entity chain: ");
8349 Write_Name (Chars (S));
8352 while Present (E) loop
8353 Write_Str (" "); Write_Int (Int (E));
8360 -- Generate warning for hiding
8363 and then Comes_From_Source (S)
8364 and then In_Extended_Main_Source_Unit (S)
8371 -- Warn unless genuine overloading. Do not emit warning on
8372 -- hiding predefined operators in Standard (these are either an
8373 -- (artifact of our implicit declarations, or simple noise) but
8374 -- keep warning on a operator defined on a local subtype, because
8375 -- of the real danger that different operators may be applied in
8376 -- various parts of the program.
8378 -- Note that if E and S have the same scope, there is never any
8379 -- hiding. Either the two conflict, and the program is illegal,
8380 -- or S is overriding an implicit inherited subprogram.
8382 if Scope (E) /= Scope (S)
8383 and then (not Is_Overloadable (E)
8384 or else Subtype_Conformant (E, S))
8385 and then (Is_Immediately_Visible (E)
8386 or else Is_Potentially_Use_Visible (S))
8388 if Scope (E) = Standard_Standard then
8389 if Nkind (S) = N_Defining_Operator_Symbol
8390 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8392 and then Matches_Predefined_Op
8395 ("declaration of & hides predefined operator?h?", S);
8398 -- E not immediately within Standard
8401 Error_Msg_Sloc := Sloc (E);
8402 Error_Msg_N ("declaration of & hides one #?h?", S);
8407 end Enter_Overloaded_Entity;
8409 -----------------------------
8410 -- Check_Untagged_Equality --
8411 -----------------------------
8413 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8414 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8415 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8419 -- This check applies only if we have a subprogram declaration with an
8420 -- untagged record type.
8422 if Nkind (Decl) /= N_Subprogram_Declaration
8423 or else not Is_Record_Type (Typ)
8424 or else Is_Tagged_Type (Typ)
8429 -- In Ada 2012 case, we will output errors or warnings depending on
8430 -- the setting of debug flag -gnatd.E.
8432 if Ada_Version >= Ada_2012 then
8433 Error_Msg_Warn := Debug_Flag_Dot_EE;
8435 -- In earlier versions of Ada, nothing to do unless we are warning on
8436 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8439 if not Warn_On_Ada_2012_Compatibility then
8444 -- Cases where the type has already been frozen
8446 if Is_Frozen (Typ) then
8448 -- The check applies to a primitive operation, so check that type
8449 -- and equality operation are in the same scope.
8451 if Scope (Typ) /= Current_Scope then
8454 -- If the type is a generic actual (sub)type, the operation is not
8455 -- primitive either because the base type is declared elsewhere.
8457 elsif Is_Generic_Actual_Type (Typ) then
8460 -- Here we have a definite error of declaration after freezing
8463 if Ada_Version >= Ada_2012 then
8465 ("equality operator must be declared before type & is "
8466 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8468 -- In Ada 2012 mode with error turned to warning, output one
8469 -- more warning to warn that the equality operation may not
8470 -- compose. This is the consequence of ignoring the error.
8472 if Error_Msg_Warn then
8473 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8478 ("equality operator must be declared before type& is "
8479 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8482 -- If we are in the package body, we could just move the
8483 -- declaration to the package spec, so add a message saying that.
8485 if In_Package_Body (Scope (Typ)) then
8486 if Ada_Version >= Ada_2012 then
8488 ("\move declaration to package spec<<", Eq_Op);
8491 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8494 -- Otherwise try to find the freezing point for better message.
8497 Obj_Decl := Next (Parent (Typ));
8498 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8499 if Nkind (Obj_Decl) = N_Object_Declaration
8500 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8502 -- Freezing point, output warnings
8504 if Ada_Version >= Ada_2012 then
8506 ("type& is frozen by declaration??", Obj_Decl, Typ);
8508 ("\an equality operator cannot be declared after "
8513 ("type& is frozen by declaration (Ada 2012)?y?",
8516 ("\an equality operator cannot be declared after "
8517 & "this point (Ada 2012)?y?",
8523 -- If we reach generated code for subprogram declaration
8524 -- or body, it is the body that froze the type and the
8525 -- declaration is legal.
8527 elsif Sloc (Obj_Decl) = Sloc (Decl) then
8536 -- Here if type is not frozen yet. It is illegal to have a primitive
8537 -- equality declared in the private part if the type is visible.
8539 elsif not In_Same_List (Parent (Typ), Decl)
8540 and then not Is_Limited_Type (Typ)
8542 -- Shouldn't we give an RM reference here???
8544 if Ada_Version >= Ada_2012 then
8546 ("equality operator appears too late<<", Eq_Op);
8549 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8552 -- No error detected
8557 end Check_Untagged_Equality;
8559 -----------------------------
8560 -- Find_Corresponding_Spec --
8561 -----------------------------
8563 function Find_Corresponding_Spec
8565 Post_Error : Boolean := True) return Entity_Id
8567 Spec : constant Node_Id := Specification (N);
8568 Designator : constant Entity_Id := Defining_Entity (Spec);
8572 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8573 -- Even if fully conformant, a body may depend on a generic actual when
8574 -- the spec does not, or vice versa, in which case they were distinct
8575 -- entities in the generic.
8577 -------------------------------
8578 -- Different_Generic_Profile --
8579 -------------------------------
8581 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8584 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8585 -- Check that the types of corresponding formals have the same
8586 -- generic actual if any. We have to account for subtypes of a
8587 -- generic formal, declared between a spec and a body, which may
8588 -- appear distinct in an instance but matched in the generic, and
8589 -- the subtype may be used either in the spec or the body of the
8590 -- subprogram being checked.
8592 -------------------------
8593 -- Same_Generic_Actual --
8594 -------------------------
8596 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8598 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8599 -- Predicate to check whether S1 is a subtype of S2 in the source
8602 -------------------------
8603 -- Is_Declared_Subtype --
8604 -------------------------
8606 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8608 return Comes_From_Source (Parent (S1))
8609 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8610 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8611 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8612 end Is_Declared_Subtype;
8614 -- Start of processing for Same_Generic_Actual
8617 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8618 or else Is_Declared_Subtype (T1, T2)
8619 or else Is_Declared_Subtype (T2, T1);
8620 end Same_Generic_Actual;
8622 -- Start of processing for Different_Generic_Profile
8625 if not In_Instance then
8628 elsif Ekind (E) = E_Function
8629 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8634 F1 := First_Formal (Designator);
8635 F2 := First_Formal (E);
8636 while Present (F1) loop
8637 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8646 end Different_Generic_Profile;
8648 -- Start of processing for Find_Corresponding_Spec
8651 E := Current_Entity (Designator);
8652 while Present (E) loop
8654 -- We are looking for a matching spec. It must have the same scope,
8655 -- and the same name, and either be type conformant, or be the case
8656 -- of a library procedure spec and its body (which belong to one
8657 -- another regardless of whether they are type conformant or not).
8659 if Scope (E) = Current_Scope then
8660 if Current_Scope = Standard_Standard
8661 or else (Ekind (E) = Ekind (Designator)
8662 and then Type_Conformant (E, Designator))
8664 -- Within an instantiation, we know that spec and body are
8665 -- subtype conformant, because they were subtype conformant in
8666 -- the generic. We choose the subtype-conformant entity here as
8667 -- well, to resolve spurious ambiguities in the instance that
8668 -- were not present in the generic (i.e. when two different
8669 -- types are given the same actual). If we are looking for a
8670 -- spec to match a body, full conformance is expected.
8674 -- Inherit the convention and "ghostness" of the matching
8675 -- spec to ensure proper full and subtype conformance.
8677 Set_Convention (Designator, Convention (E));
8679 -- Skip past subprogram bodies and subprogram renamings that
8680 -- may appear to have a matching spec, but that aren't fully
8681 -- conformant with it. That can occur in cases where an
8682 -- actual type causes unrelated homographs in the instance.
8684 if Nkind_In (N, N_Subprogram_Body,
8685 N_Subprogram_Renaming_Declaration)
8686 and then Present (Homonym (E))
8687 and then not Fully_Conformant (Designator, E)
8691 elsif not Subtype_Conformant (Designator, E) then
8694 elsif Different_Generic_Profile (E) then
8699 -- Ada 2012 (AI05-0165): For internally generated bodies of
8700 -- null procedures locate the internally generated spec. We
8701 -- enforce mode conformance since a tagged type may inherit
8702 -- from interfaces several null primitives which differ only
8703 -- in the mode of the formals.
8705 if not (Comes_From_Source (E))
8706 and then Is_Null_Procedure (E)
8707 and then not Mode_Conformant (Designator, E)
8711 -- For null procedures coming from source that are completions,
8712 -- analysis of the generated body will establish the link.
8714 elsif Comes_From_Source (E)
8715 and then Nkind (Spec) = N_Procedure_Specification
8716 and then Null_Present (Spec)
8720 -- Expression functions can be completions, but cannot be
8721 -- completed by an explicit body.
8723 elsif Comes_From_Source (E)
8724 and then Comes_From_Source (N)
8725 and then Nkind (N) = N_Subprogram_Body
8726 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8727 N_Expression_Function
8729 Error_Msg_Sloc := Sloc (E);
8730 Error_Msg_N ("body conflicts with expression function#", N);
8733 elsif not Has_Completion (E) then
8734 if Nkind (N) /= N_Subprogram_Body_Stub then
8735 Set_Corresponding_Spec (N, E);
8738 Set_Has_Completion (E);
8741 elsif Nkind (Parent (N)) = N_Subunit then
8743 -- If this is the proper body of a subunit, the completion
8744 -- flag is set when analyzing the stub.
8748 -- If E is an internal function with a controlling result that
8749 -- was created for an operation inherited by a null extension,
8750 -- it may be overridden by a body without a previous spec (one
8751 -- more reason why these should be shunned). In that case we
8752 -- remove the generated body if present, because the current
8753 -- one is the explicit overriding.
8755 elsif Ekind (E) = E_Function
8756 and then Ada_Version >= Ada_2005
8757 and then not Comes_From_Source (E)
8758 and then Has_Controlling_Result (E)
8759 and then Is_Null_Extension (Etype (E))
8760 and then Comes_From_Source (Spec)
8762 Set_Has_Completion (E, False);
8765 and then Nkind (Parent (E)) = N_Function_Specification
8768 (Unit_Declaration_Node
8769 (Corresponding_Body (Unit_Declaration_Node (E))));
8773 -- If expansion is disabled, or if the wrapper function has
8774 -- not been generated yet, this a late body overriding an
8775 -- inherited operation, or it is an overriding by some other
8776 -- declaration before the controlling result is frozen. In
8777 -- either case this is a declaration of a new entity.
8783 -- If the body already exists, then this is an error unless
8784 -- the previous declaration is the implicit declaration of a
8785 -- derived subprogram. It is also legal for an instance to
8786 -- contain type conformant overloadable declarations (but the
8787 -- generic declaration may not), per 8.3(26/2).
8789 elsif No (Alias (E))
8790 and then not Is_Intrinsic_Subprogram (E)
8791 and then not In_Instance
8794 Error_Msg_Sloc := Sloc (E);
8796 if Is_Imported (E) then
8798 ("body not allowed for imported subprogram & declared#",
8801 Error_Msg_NE ("duplicate body for & declared#", N, E);
8805 -- Child units cannot be overloaded, so a conformance mismatch
8806 -- between body and a previous spec is an error.
8808 elsif Is_Child_Unit (E)
8810 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8812 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8817 ("body of child unit does not match previous declaration", N);
8825 -- On exit, we know that no previous declaration of subprogram exists
8828 end Find_Corresponding_Spec;
8830 ----------------------
8831 -- Fully_Conformant --
8832 ----------------------
8834 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8837 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8839 end Fully_Conformant;
8841 ----------------------------------
8842 -- Fully_Conformant_Expressions --
8843 ----------------------------------
8845 function Fully_Conformant_Expressions
8846 (Given_E1 : Node_Id;
8848 Report : Boolean := False) return Boolean
8850 E1 : constant Node_Id := Original_Node (Given_E1);
8851 E2 : constant Node_Id := Original_Node (Given_E2);
8852 -- We always test conformance on original nodes, since it is possible
8853 -- for analysis and/or expansion to make things look as though they
8854 -- conform when they do not, e.g. by converting 1+2 into 3.
8856 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean;
8859 function FCL (L1 : List_Id; L2 : List_Id) return Boolean;
8860 -- Compare elements of two lists for conformance. Elements have to be
8861 -- conformant, and actuals inserted as default parameters do not match
8862 -- explicit actuals with the same value.
8864 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean;
8865 -- Compare an operator node with a function call
8871 function FCE (Given_E1 : Node_Id; Given_E2 : Node_Id) return Boolean is
8873 return Fully_Conformant_Expressions (Given_E1, Given_E2, Report);
8880 function FCL (L1 : List_Id; L2 : List_Id) return Boolean is
8885 if L1 = No_List then
8891 if L2 = No_List then
8897 -- Compare two lists, skipping rewrite insertions (we want to compare
8898 -- the original trees, not the expanded versions).
8901 if Is_Rewrite_Insertion (N1) then
8903 elsif Is_Rewrite_Insertion (N2) then
8909 elsif not FCE (N1, N2) then
8922 function FCO (Op_Node : Node_Id; Call_Node : Node_Id) return Boolean is
8923 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8928 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8933 Act := First (Actuals);
8935 if Nkind (Op_Node) in N_Binary_Op then
8936 if not FCE (Left_Opnd (Op_Node), Act) then
8943 return Present (Act)
8944 and then FCE (Right_Opnd (Op_Node), Act)
8945 and then No (Next (Act));
8953 -- Start of processing for Fully_Conformant_Expressions
8958 -- Nonconformant if paren count does not match. Note: if some idiot
8959 -- complains that we don't do this right for more than 3 levels of
8960 -- parentheses, they will be treated with the respect they deserve.
8962 if Paren_Count (E1) /= Paren_Count (E2) then
8965 -- If same entities are referenced, then they are conformant even if
8966 -- they have different forms (RM 8.3.1(19-20)).
8968 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8969 if Present (Entity (E1)) then
8970 Result := Entity (E1) = Entity (E2)
8972 -- One may be a discriminant that has been replaced by the
8973 -- corresponding discriminal.
8976 (Chars (Entity (E1)) = Chars (Entity (E2))
8977 and then Ekind (Entity (E1)) = E_Discriminant
8978 and then Ekind (Entity (E2)) = E_In_Parameter)
8980 -- The discriminant of a protected type is transformed into
8981 -- a local constant and then into a parameter of a protected
8985 (Ekind (Entity (E1)) = E_Constant
8986 and then Ekind (Entity (E2)) = E_In_Parameter
8987 and then Present (Discriminal_Link (Entity (E1)))
8988 and then Discriminal_Link (Entity (E1)) =
8989 Discriminal_Link (Entity (E2)))
8991 -- AI12-050: The loop variables of quantified expressions match
8992 -- if they have the same identifier, even though they may have
8993 -- different entities.
8996 (Chars (Entity (E1)) = Chars (Entity (E2))
8997 and then Ekind (Entity (E1)) = E_Loop_Parameter
8998 and then Ekind (Entity (E2)) = E_Loop_Parameter)
9000 -- A call to an instantiation of Unchecked_Conversion is
9001 -- rewritten with the name of the generated function created for
9002 -- the instance, and this must be special-cased.
9005 (Ekind (Entity (E1)) = E_Function
9006 and then Is_Intrinsic_Subprogram (Entity (E1))
9007 and then Is_Generic_Instance (Entity (E1))
9008 and then Entity (E2) = Alias (Entity (E1)));
9009 if Report and not Result then
9011 Text_Ptr'Max (Sloc (Entity (E1)), Sloc (Entity (E2)));
9013 ("Meaning of& differs because of declaration#", E1, E2);
9018 elsif Nkind (E1) = N_Expanded_Name
9019 and then Nkind (E2) = N_Expanded_Name
9020 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9021 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9023 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9026 -- Identifiers in component associations don't always have
9027 -- entities, but their names must conform.
9029 return Nkind (E1) = N_Identifier
9030 and then Nkind (E2) = N_Identifier
9031 and then Chars (E1) = Chars (E2);
9034 elsif Nkind (E1) = N_Character_Literal
9035 and then Nkind (E2) = N_Expanded_Name
9037 return Nkind (Selector_Name (E2)) = N_Character_Literal
9038 and then Chars (E1) = Chars (Selector_Name (E2));
9040 elsif Nkind (E2) = N_Character_Literal
9041 and then Nkind (E1) = N_Expanded_Name
9043 return Nkind (Selector_Name (E1)) = N_Character_Literal
9044 and then Chars (E2) = Chars (Selector_Name (E1));
9046 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9047 return FCO (E1, E2);
9049 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9050 return FCO (E2, E1);
9052 -- Otherwise we must have the same syntactic entity
9054 elsif Nkind (E1) /= Nkind (E2) then
9057 -- At this point, we specialize by node type
9063 FCL (Expressions (E1), Expressions (E2))
9065 FCL (Component_Associations (E1),
9066 Component_Associations (E2));
9069 if Nkind (Expression (E1)) = N_Qualified_Expression
9071 Nkind (Expression (E2)) = N_Qualified_Expression
9073 return FCE (Expression (E1), Expression (E2));
9075 -- Check that the subtype marks and any constraints
9080 Indic1 : constant Node_Id := Expression (E1);
9081 Indic2 : constant Node_Id := Expression (E2);
9086 if Nkind (Indic1) /= N_Subtype_Indication then
9088 Nkind (Indic2) /= N_Subtype_Indication
9089 and then Entity (Indic1) = Entity (Indic2);
9091 elsif Nkind (Indic2) /= N_Subtype_Indication then
9093 Nkind (Indic1) /= N_Subtype_Indication
9094 and then Entity (Indic1) = Entity (Indic2);
9097 if Entity (Subtype_Mark (Indic1)) /=
9098 Entity (Subtype_Mark (Indic2))
9103 Elt1 := First (Constraints (Constraint (Indic1)));
9104 Elt2 := First (Constraints (Constraint (Indic2)));
9105 while Present (Elt1) and then Present (Elt2) loop
9106 if not FCE (Elt1, Elt2) then
9119 when N_Attribute_Reference =>
9121 Attribute_Name (E1) = Attribute_Name (E2)
9122 and then FCL (Expressions (E1), Expressions (E2));
9126 Entity (E1) = Entity (E2)
9127 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9128 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9130 when N_Membership_Test
9134 FCE (Left_Opnd (E1), Left_Opnd (E2))
9136 FCE (Right_Opnd (E1), Right_Opnd (E2));
9138 when N_Case_Expression =>
9144 if not FCE (Expression (E1), Expression (E2)) then
9148 Alt1 := First (Alternatives (E1));
9149 Alt2 := First (Alternatives (E2));
9151 if Present (Alt1) /= Present (Alt2) then
9153 elsif No (Alt1) then
9157 if not FCE (Expression (Alt1), Expression (Alt2))
9158 or else not FCL (Discrete_Choices (Alt1),
9159 Discrete_Choices (Alt2))
9170 when N_Character_Literal =>
9172 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9174 when N_Component_Association =>
9176 FCL (Choices (E1), Choices (E2))
9178 FCE (Expression (E1), Expression (E2));
9180 when N_Explicit_Dereference =>
9182 FCE (Prefix (E1), Prefix (E2));
9184 when N_Extension_Aggregate =>
9186 FCL (Expressions (E1), Expressions (E2))
9187 and then Null_Record_Present (E1) =
9188 Null_Record_Present (E2)
9189 and then FCL (Component_Associations (E1),
9190 Component_Associations (E2));
9192 when N_Function_Call =>
9194 FCE (Name (E1), Name (E2))
9196 FCL (Parameter_Associations (E1),
9197 Parameter_Associations (E2));
9199 when N_If_Expression =>
9201 FCL (Expressions (E1), Expressions (E2));
9203 when N_Indexed_Component =>
9205 FCE (Prefix (E1), Prefix (E2))
9207 FCL (Expressions (E1), Expressions (E2));
9209 when N_Integer_Literal =>
9210 return (Intval (E1) = Intval (E2));
9215 when N_Operator_Symbol =>
9217 Chars (E1) = Chars (E2);
9219 when N_Others_Choice =>
9222 when N_Parameter_Association =>
9224 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9225 and then FCE (Explicit_Actual_Parameter (E1),
9226 Explicit_Actual_Parameter (E2));
9228 when N_Qualified_Expression
9230 | N_Unchecked_Type_Conversion
9233 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9235 FCE (Expression (E1), Expression (E2));
9237 when N_Quantified_Expression =>
9238 if not FCE (Condition (E1), Condition (E2)) then
9242 if Present (Loop_Parameter_Specification (E1))
9243 and then Present (Loop_Parameter_Specification (E2))
9246 L1 : constant Node_Id :=
9247 Loop_Parameter_Specification (E1);
9248 L2 : constant Node_Id :=
9249 Loop_Parameter_Specification (E2);
9253 Reverse_Present (L1) = Reverse_Present (L2)
9255 FCE (Defining_Identifier (L1),
9256 Defining_Identifier (L2))
9258 FCE (Discrete_Subtype_Definition (L1),
9259 Discrete_Subtype_Definition (L2));
9262 elsif Present (Iterator_Specification (E1))
9263 and then Present (Iterator_Specification (E2))
9266 I1 : constant Node_Id := Iterator_Specification (E1);
9267 I2 : constant Node_Id := Iterator_Specification (E2);
9271 FCE (Defining_Identifier (I1),
9272 Defining_Identifier (I2))
9274 Of_Present (I1) = Of_Present (I2)
9276 Reverse_Present (I1) = Reverse_Present (I2)
9277 and then FCE (Name (I1), Name (I2))
9278 and then FCE (Subtype_Indication (I1),
9279 Subtype_Indication (I2));
9282 -- The quantified expressions used different specifications to
9283 -- walk their respective ranges.
9291 FCE (Low_Bound (E1), Low_Bound (E2))
9293 FCE (High_Bound (E1), High_Bound (E2));
9295 when N_Real_Literal =>
9296 return (Realval (E1) = Realval (E2));
9298 when N_Selected_Component =>
9300 FCE (Prefix (E1), Prefix (E2))
9302 FCE (Selector_Name (E1), Selector_Name (E2));
9306 FCE (Prefix (E1), Prefix (E2))
9308 FCE (Discrete_Range (E1), Discrete_Range (E2));
9310 when N_String_Literal =>
9312 S1 : constant String_Id := Strval (E1);
9313 S2 : constant String_Id := Strval (E2);
9314 L1 : constant Nat := String_Length (S1);
9315 L2 : constant Nat := String_Length (S2);
9322 for J in 1 .. L1 loop
9323 if Get_String_Char (S1, J) /=
9324 Get_String_Char (S2, J)
9336 Entity (E1) = Entity (E2)
9338 FCE (Right_Opnd (E1), Right_Opnd (E2));
9340 -- All other node types cannot appear in this context. Strictly
9341 -- we should raise a fatal internal error. Instead we just ignore
9342 -- the nodes. This means that if anyone makes a mistake in the
9343 -- expander and mucks an expression tree irretrievably, the result
9344 -- will be a failure to detect a (probably very obscure) case
9345 -- of non-conformance, which is better than bombing on some
9346 -- case where two expressions do in fact conform.
9352 end Fully_Conformant_Expressions;
9354 ----------------------------------------
9355 -- Fully_Conformant_Discrete_Subtypes --
9356 ----------------------------------------
9358 function Fully_Conformant_Discrete_Subtypes
9359 (Given_S1 : Node_Id;
9360 Given_S2 : Node_Id) return Boolean
9362 S1 : constant Node_Id := Original_Node (Given_S1);
9363 S2 : constant Node_Id := Original_Node (Given_S2);
9365 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9366 -- Special-case for a bound given by a discriminant, which in the body
9367 -- is replaced with the discriminal of the enclosing type.
9369 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9370 -- Check both bounds
9372 -----------------------
9373 -- Conforming_Bounds --
9374 -----------------------
9376 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9378 if Is_Entity_Name (B1)
9379 and then Is_Entity_Name (B2)
9380 and then Ekind (Entity (B1)) = E_Discriminant
9382 return Chars (B1) = Chars (B2);
9385 return Fully_Conformant_Expressions (B1, B2);
9387 end Conforming_Bounds;
9389 -----------------------
9390 -- Conforming_Ranges --
9391 -----------------------
9393 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9396 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9398 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9399 end Conforming_Ranges;
9401 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9404 if Nkind (S1) /= Nkind (S2) then
9407 elsif Is_Entity_Name (S1) then
9408 return Entity (S1) = Entity (S2);
9410 elsif Nkind (S1) = N_Range then
9411 return Conforming_Ranges (S1, S2);
9413 elsif Nkind (S1) = N_Subtype_Indication then
9415 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9418 (Range_Expression (Constraint (S1)),
9419 Range_Expression (Constraint (S2)));
9423 end Fully_Conformant_Discrete_Subtypes;
9425 --------------------
9426 -- Install_Entity --
9427 --------------------
9429 procedure Install_Entity (E : Entity_Id) is
9430 Prev : constant Entity_Id := Current_Entity (E);
9432 Set_Is_Immediately_Visible (E);
9433 Set_Current_Entity (E);
9434 Set_Homonym (E, Prev);
9437 ---------------------
9438 -- Install_Formals --
9439 ---------------------
9441 procedure Install_Formals (Id : Entity_Id) is
9444 F := First_Formal (Id);
9445 while Present (F) loop
9449 end Install_Formals;
9451 -----------------------------
9452 -- Is_Interface_Conformant --
9453 -----------------------------
9455 function Is_Interface_Conformant
9456 (Tagged_Type : Entity_Id;
9457 Iface_Prim : Entity_Id;
9458 Prim : Entity_Id) return Boolean
9460 -- The operation may in fact be an inherited (implicit) operation
9461 -- rather than the original interface primitive, so retrieve the
9462 -- ultimate ancestor.
9464 Iface : constant Entity_Id :=
9465 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9466 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9468 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9469 -- Return the controlling formal of Prim
9471 ------------------------
9472 -- Controlling_Formal --
9473 ------------------------
9475 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9479 E := First_Entity (Prim);
9480 while Present (E) loop
9481 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9489 end Controlling_Formal;
9493 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9494 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9496 -- Start of processing for Is_Interface_Conformant
9499 pragma Assert (Is_Subprogram (Iface_Prim)
9500 and then Is_Subprogram (Prim)
9501 and then Is_Dispatching_Operation (Iface_Prim)
9502 and then Is_Dispatching_Operation (Prim));
9504 pragma Assert (Is_Interface (Iface)
9505 or else (Present (Alias (Iface_Prim))
9508 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9510 if Prim = Iface_Prim
9511 or else not Is_Subprogram (Prim)
9512 or else Ekind (Prim) /= Ekind (Iface_Prim)
9513 or else not Is_Dispatching_Operation (Prim)
9514 or else Scope (Prim) /= Scope (Tagged_Type)
9516 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9517 or else not Primitive_Names_Match (Iface_Prim, Prim)
9521 -- The mode of the controlling formals must match
9523 elsif Present (Iface_Ctrl_F)
9524 and then Present (Prim_Ctrl_F)
9525 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9529 -- Case of a procedure, or a function whose result type matches the
9530 -- result type of the interface primitive, or a function that has no
9531 -- controlling result (I or access I).
9533 elsif Ekind (Iface_Prim) = E_Procedure
9534 or else Etype (Prim) = Etype (Iface_Prim)
9535 or else not Has_Controlling_Result (Prim)
9537 return Type_Conformant
9538 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9540 -- Case of a function returning an interface, or an access to one. Check
9541 -- that the return types correspond.
9543 elsif Implements_Interface (Typ, Iface) then
9544 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9546 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9551 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9552 Skip_Controlling_Formals => True);
9558 end Is_Interface_Conformant;
9560 ---------------------------------
9561 -- Is_Non_Overriding_Operation --
9562 ---------------------------------
9564 function Is_Non_Overriding_Operation
9565 (Prev_E : Entity_Id;
9566 New_E : Entity_Id) return Boolean
9570 G_Typ : Entity_Id := Empty;
9572 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9573 -- If F_Type is a derived type associated with a generic actual subtype,
9574 -- then return its Generic_Parent_Type attribute, else return Empty.
9576 function Types_Correspond
9577 (P_Type : Entity_Id;
9578 N_Type : Entity_Id) return Boolean;
9579 -- Returns true if and only if the types (or designated types in the
9580 -- case of anonymous access types) are the same or N_Type is derived
9581 -- directly or indirectly from P_Type.
9583 -----------------------------
9584 -- Get_Generic_Parent_Type --
9585 -----------------------------
9587 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9593 if Is_Derived_Type (F_Typ)
9594 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9596 -- The tree must be traversed to determine the parent subtype in
9597 -- the generic unit, which unfortunately isn't always available
9598 -- via semantic attributes. ??? (Note: The use of Original_Node
9599 -- is needed for cases where a full derived type has been
9602 -- If the parent type is a scalar type, the derivation creates
9603 -- an anonymous base type for it, and the source type is its
9606 if Is_Scalar_Type (F_Typ)
9607 and then not Comes_From_Source (F_Typ)
9611 (Original_Node (Parent (First_Subtype (F_Typ))));
9613 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9615 if Nkind (Defn) = N_Derived_Type_Definition then
9616 Indic := Subtype_Indication (Defn);
9618 if Nkind (Indic) = N_Subtype_Indication then
9619 G_Typ := Entity (Subtype_Mark (Indic));
9621 G_Typ := Entity (Indic);
9624 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9625 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9627 return Generic_Parent_Type (Parent (G_Typ));
9633 end Get_Generic_Parent_Type;
9635 ----------------------
9636 -- Types_Correspond --
9637 ----------------------
9639 function Types_Correspond
9640 (P_Type : Entity_Id;
9641 N_Type : Entity_Id) return Boolean
9643 Prev_Type : Entity_Id := Base_Type (P_Type);
9644 New_Type : Entity_Id := Base_Type (N_Type);
9647 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9648 Prev_Type := Designated_Type (Prev_Type);
9651 if Ekind (New_Type) = E_Anonymous_Access_Type then
9652 New_Type := Designated_Type (New_Type);
9655 if Prev_Type = New_Type then
9658 elsif not Is_Class_Wide_Type (New_Type) then
9659 while Etype (New_Type) /= New_Type loop
9660 New_Type := Etype (New_Type);
9662 if New_Type = Prev_Type then
9668 end Types_Correspond;
9670 -- Start of processing for Is_Non_Overriding_Operation
9673 -- In the case where both operations are implicit derived subprograms
9674 -- then neither overrides the other. This can only occur in certain
9675 -- obscure cases (e.g., derivation from homographs created in a generic
9678 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9681 elsif Ekind (Current_Scope) = E_Package
9682 and then Is_Generic_Instance (Current_Scope)
9683 and then In_Private_Part (Current_Scope)
9684 and then Comes_From_Source (New_E)
9686 -- We examine the formals and result type of the inherited operation,
9687 -- to determine whether their type is derived from (the instance of)
9688 -- a generic type. The first such formal or result type is the one
9691 Formal := First_Formal (Prev_E);
9693 while Present (Formal) loop
9694 F_Typ := Base_Type (Etype (Formal));
9696 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9697 F_Typ := Designated_Type (F_Typ);
9700 G_Typ := Get_Generic_Parent_Type (F_Typ);
9701 exit when Present (G_Typ);
9703 Next_Formal (Formal);
9706 -- If the function dispatches on result check the result type
9708 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9709 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9716 -- If the generic type is a private type, then the original operation
9717 -- was not overriding in the generic, because there was no primitive
9718 -- operation to override.
9720 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9721 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9722 N_Formal_Private_Type_Definition
9726 -- The generic parent type is the ancestor of a formal derived
9727 -- type declaration. We need to check whether it has a primitive
9728 -- operation that should be overridden by New_E in the generic.
9732 P_Formal : Entity_Id;
9733 N_Formal : Entity_Id;
9737 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9740 while Present (Prim_Elt) loop
9741 P_Prim := Node (Prim_Elt);
9743 if Chars (P_Prim) = Chars (New_E)
9744 and then Ekind (P_Prim) = Ekind (New_E)
9746 P_Formal := First_Formal (P_Prim);
9747 N_Formal := First_Formal (New_E);
9748 while Present (P_Formal) and then Present (N_Formal) loop
9749 P_Typ := Etype (P_Formal);
9750 N_Typ := Etype (N_Formal);
9752 if not Types_Correspond (P_Typ, N_Typ) then
9756 Next_Entity (P_Formal);
9757 Next_Entity (N_Formal);
9760 -- Found a matching primitive operation belonging to the
9761 -- formal ancestor type, so the new subprogram is
9765 and then No (N_Formal)
9766 and then (Ekind (New_E) /= E_Function
9769 (Etype (P_Prim), Etype (New_E)))
9775 Next_Elmt (Prim_Elt);
9778 -- If no match found, then the new subprogram does not override
9779 -- in the generic (nor in the instance).
9781 -- If the type in question is not abstract, and the subprogram
9782 -- is, this will be an error if the new operation is in the
9783 -- private part of the instance. Emit a warning now, which will
9784 -- make the subsequent error message easier to understand.
9786 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9787 and then Is_Abstract_Subprogram (Prev_E)
9788 and then In_Private_Part (Current_Scope)
9790 Error_Msg_Node_2 := F_Typ;
9792 ("private operation& in generic unit does not override "
9793 & "any primitive operation of& (RM 12.3 (18))??",
9803 end Is_Non_Overriding_Operation;
9805 -------------------------------------
9806 -- List_Inherited_Pre_Post_Aspects --
9807 -------------------------------------
9809 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9811 if Opt.List_Inherited_Aspects
9812 and then Is_Subprogram_Or_Generic_Subprogram (E)
9815 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9820 for Index in Subps'Range loop
9821 Items := Contract (Subps (Index));
9823 if Present (Items) then
9824 Prag := Pre_Post_Conditions (Items);
9825 while Present (Prag) loop
9826 Error_Msg_Sloc := Sloc (Prag);
9828 if Class_Present (Prag)
9829 and then not Split_PPC (Prag)
9831 if Pragma_Name (Prag) = Name_Precondition then
9833 ("info: & inherits `Pre''Class` aspect from "
9837 ("info: & inherits `Post''Class` aspect from "
9842 Prag := Next_Pragma (Prag);
9848 end List_Inherited_Pre_Post_Aspects;
9850 ------------------------------
9851 -- Make_Inequality_Operator --
9852 ------------------------------
9854 -- S is the defining identifier of an equality operator. We build a
9855 -- subprogram declaration with the right signature. This operation is
9856 -- intrinsic, because it is always expanded as the negation of the
9857 -- call to the equality function.
9859 procedure Make_Inequality_Operator (S : Entity_Id) is
9860 Loc : constant Source_Ptr := Sloc (S);
9863 Op_Name : Entity_Id;
9865 FF : constant Entity_Id := First_Formal (S);
9866 NF : constant Entity_Id := Next_Formal (FF);
9869 -- Check that equality was properly defined, ignore call if not
9876 A : constant Entity_Id :=
9877 Make_Defining_Identifier (Sloc (FF),
9878 Chars => Chars (FF));
9880 B : constant Entity_Id :=
9881 Make_Defining_Identifier (Sloc (NF),
9882 Chars => Chars (NF));
9885 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9887 Formals := New_List (
9888 Make_Parameter_Specification (Loc,
9889 Defining_Identifier => A,
9891 New_Occurrence_Of (Etype (First_Formal (S)),
9892 Sloc (Etype (First_Formal (S))))),
9894 Make_Parameter_Specification (Loc,
9895 Defining_Identifier => B,
9897 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9898 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9901 Make_Subprogram_Declaration (Loc,
9903 Make_Function_Specification (Loc,
9904 Defining_Unit_Name => Op_Name,
9905 Parameter_Specifications => Formals,
9906 Result_Definition =>
9907 New_Occurrence_Of (Standard_Boolean, Loc)));
9909 -- Insert inequality right after equality if it is explicit or after
9910 -- the derived type when implicit. These entities are created only
9911 -- for visibility purposes, and eventually replaced in the course
9912 -- of expansion, so they do not need to be attached to the tree and
9913 -- seen by the back-end. Keeping them internal also avoids spurious
9914 -- freezing problems. The declaration is inserted in the tree for
9915 -- analysis, and removed afterwards. If the equality operator comes
9916 -- from an explicit declaration, attach the inequality immediately
9917 -- after. Else the equality is inherited from a derived type
9918 -- declaration, so insert inequality after that declaration.
9920 if No (Alias (S)) then
9921 Insert_After (Unit_Declaration_Node (S), Decl);
9922 elsif Is_List_Member (Parent (S)) then
9923 Insert_After (Parent (S), Decl);
9925 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9928 Mark_Rewrite_Insertion (Decl);
9929 Set_Is_Intrinsic_Subprogram (Op_Name);
9932 Set_Has_Completion (Op_Name);
9933 Set_Corresponding_Equality (Op_Name, S);
9934 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9936 end Make_Inequality_Operator;
9938 ----------------------
9939 -- May_Need_Actuals --
9940 ----------------------
9942 procedure May_Need_Actuals (Fun : Entity_Id) is
9947 F := First_Formal (Fun);
9949 while Present (F) loop
9950 if No (Default_Value (F)) then
9958 Set_Needs_No_Actuals (Fun, B);
9959 end May_Need_Actuals;
9961 ---------------------
9962 -- Mode_Conformant --
9963 ---------------------
9965 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9968 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9970 end Mode_Conformant;
9972 ---------------------------
9973 -- New_Overloaded_Entity --
9974 ---------------------------
9976 procedure New_Overloaded_Entity
9978 Derived_Type : Entity_Id := Empty)
9980 Overridden_Subp : Entity_Id := Empty;
9981 -- Set if the current scope has an operation that is type-conformant
9982 -- with S, and becomes hidden by S.
9984 Is_Primitive_Subp : Boolean;
9985 -- Set to True if the new subprogram is primitive
9988 -- Entity that S overrides
9990 procedure Check_For_Primitive_Subprogram
9991 (Is_Primitive : out Boolean;
9992 Is_Overriding : Boolean := False);
9993 -- If the subprogram being analyzed is a primitive operation of the type
9994 -- of a formal or result, set the Has_Primitive_Operations flag on the
9995 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9996 -- corresponding flag on the entity itself for later use.
9998 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9999 -- True if a) E is a subprogram whose first formal is a concurrent type
10000 -- defined in the scope of E that has some entry or subprogram whose
10001 -- profile matches E, or b) E is an internally built dispatching
10002 -- subprogram of a protected type and there is a matching subprogram
10003 -- defined in the enclosing scope of the protected type, or c) E is
10004 -- an entry of a synchronized type and a matching procedure has been
10005 -- previously defined in the enclosing scope of the synchronized type.
10007 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10008 -- Check that E is declared in the private part of the current package,
10009 -- or in the package body, where it may hide a previous declaration.
10010 -- We can't use In_Private_Part by itself because this flag is also
10011 -- set when freezing entities, so we must examine the place of the
10012 -- declaration in the tree, and recognize wrapper packages as well.
10014 function Is_Overriding_Alias
10015 (Old_E : Entity_Id;
10016 New_E : Entity_Id) return Boolean;
10017 -- Check whether new subprogram and old subprogram are both inherited
10018 -- from subprograms that have distinct dispatch table entries. This can
10019 -- occur with derivations from instances with accidental homonyms. The
10020 -- function is conservative given that the converse is only true within
10021 -- instances that contain accidental overloadings.
10023 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10024 -- Report conflict between entities S and E
10026 ------------------------------------
10027 -- Check_For_Primitive_Subprogram --
10028 ------------------------------------
10030 procedure Check_For_Primitive_Subprogram
10031 (Is_Primitive : out Boolean;
10032 Is_Overriding : Boolean := False)
10034 Formal : Entity_Id;
10038 function Visible_Part_Type (T : Entity_Id) return Boolean;
10039 -- Returns true if T is declared in the visible part of the current
10040 -- package scope; otherwise returns false. Assumes that T is declared
10043 procedure Check_Private_Overriding (T : Entity_Id);
10044 -- Checks that if a primitive abstract subprogram of a visible
10045 -- abstract type is declared in a private part, then it must override
10046 -- an abstract subprogram declared in the visible part. Also checks
10047 -- that if a primitive function with a controlling result is declared
10048 -- in a private part, then it must override a function declared in
10049 -- the visible part.
10051 ------------------------------
10052 -- Check_Private_Overriding --
10053 ------------------------------
10055 procedure Check_Private_Overriding (T : Entity_Id) is
10056 function Overrides_Private_Part_Op return Boolean;
10057 -- This detects the special case where the overriding subprogram
10058 -- is overriding a subprogram that was declared in the same
10059 -- private part. That case is illegal by 3.9.3(10).
10061 function Overrides_Visible_Function
10062 (Partial_View : Entity_Id) return Boolean;
10063 -- True if S overrides a function in the visible part. The
10064 -- overridden function could be explicitly or implicitly declared.
10066 -------------------------------
10067 -- Overrides_Private_Part_Op --
10068 -------------------------------
10070 function Overrides_Private_Part_Op return Boolean is
10071 Over_Decl : constant Node_Id :=
10072 Unit_Declaration_Node (Overridden_Operation (S));
10073 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10076 pragma Assert (Is_Overriding);
10078 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10080 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10082 return In_Same_List (Over_Decl, Subp_Decl);
10083 end Overrides_Private_Part_Op;
10085 --------------------------------
10086 -- Overrides_Visible_Function --
10087 --------------------------------
10089 function Overrides_Visible_Function
10090 (Partial_View : Entity_Id) return Boolean
10093 if not Is_Overriding or else not Has_Homonym (S) then
10097 if not Present (Partial_View) then
10101 -- Search through all the homonyms H of S in the current
10102 -- package spec, and return True if we find one that matches.
10103 -- Note that Parent (H) will be the declaration of the
10104 -- partial view of T for a match.
10107 H : Entity_Id := S;
10111 exit when not Present (H) or else Scope (H) /= Scope (S);
10115 N_Private_Extension_Declaration,
10116 N_Private_Type_Declaration)
10117 and then Defining_Identifier (Parent (H)) = Partial_View
10125 end Overrides_Visible_Function;
10127 -- Start of processing for Check_Private_Overriding
10130 if Is_Package_Or_Generic_Package (Current_Scope)
10131 and then In_Private_Part (Current_Scope)
10132 and then Visible_Part_Type (T)
10133 and then not In_Instance
10135 if Is_Abstract_Type (T)
10136 and then Is_Abstract_Subprogram (S)
10137 and then (not Is_Overriding
10138 or else not Is_Abstract_Subprogram (E)
10139 or else Overrides_Private_Part_Op)
10142 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10145 elsif Ekind (S) = E_Function then
10147 Partial_View : constant Entity_Id :=
10148 Incomplete_Or_Partial_View (T);
10151 if not Overrides_Visible_Function (Partial_View) then
10153 -- Here, S is "function ... return T;" declared in
10154 -- the private part, not overriding some visible
10155 -- operation. That's illegal in the tagged case
10156 -- (but not if the private type is untagged).
10158 if ((Present (Partial_View)
10159 and then Is_Tagged_Type (Partial_View))
10160 or else (not Present (Partial_View)
10161 and then Is_Tagged_Type (T)))
10162 and then T = Base_Type (Etype (S))
10165 ("private function with tagged result must"
10166 & " override visible-part function", S);
10168 ("\move subprogram to the visible part"
10169 & " (RM 3.9.3(10))", S);
10171 -- AI05-0073: extend this test to the case of a
10172 -- function with a controlling access result.
10174 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10175 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10177 not Is_Class_Wide_Type
10178 (Designated_Type (Etype (S)))
10179 and then Ada_Version >= Ada_2012
10182 ("private function with controlling access "
10183 & "result must override visible-part function",
10186 ("\move subprogram to the visible part"
10187 & " (RM 3.9.3(10))", S);
10193 end Check_Private_Overriding;
10195 -----------------------
10196 -- Visible_Part_Type --
10197 -----------------------
10199 function Visible_Part_Type (T : Entity_Id) return Boolean is
10200 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10203 -- If the entity is a private type, then it must be declared in a
10206 if Ekind (T) in Private_Kind then
10209 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10212 elsif Is_List_Member (Declaration_Node (T))
10213 and then List_Containing (Declaration_Node (T)) =
10214 Visible_Declarations (Specification (P))
10221 end Visible_Part_Type;
10223 -- Start of processing for Check_For_Primitive_Subprogram
10226 Is_Primitive := False;
10228 if not Comes_From_Source (S) then
10231 -- If subprogram is at library level, it is not primitive operation
10233 elsif Current_Scope = Standard_Standard then
10236 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10237 and then not In_Package_Body (Current_Scope))
10238 or else Is_Overriding
10240 -- For function, check return type
10242 if Ekind (S) = E_Function then
10243 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10244 F_Typ := Designated_Type (Etype (S));
10246 F_Typ := Etype (S);
10249 B_Typ := Base_Type (F_Typ);
10251 if Scope (B_Typ) = Current_Scope
10252 and then not Is_Class_Wide_Type (B_Typ)
10253 and then not Is_Generic_Type (B_Typ)
10255 Is_Primitive := True;
10256 Set_Has_Primitive_Operations (B_Typ);
10257 Set_Is_Primitive (S);
10258 Check_Private_Overriding (B_Typ);
10260 -- The Ghost policy in effect at the point of declaration
10261 -- or a tagged type and a primitive operation must match
10262 -- (SPARK RM 6.9(16)).
10264 Check_Ghost_Primitive (S, B_Typ);
10268 -- For all subprograms, check formals
10270 Formal := First_Formal (S);
10271 while Present (Formal) loop
10272 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10273 F_Typ := Designated_Type (Etype (Formal));
10275 F_Typ := Etype (Formal);
10278 B_Typ := Base_Type (F_Typ);
10280 if Ekind (B_Typ) = E_Access_Subtype then
10281 B_Typ := Base_Type (B_Typ);
10284 if Scope (B_Typ) = Current_Scope
10285 and then not Is_Class_Wide_Type (B_Typ)
10286 and then not Is_Generic_Type (B_Typ)
10288 Is_Primitive := True;
10289 Set_Is_Primitive (S);
10290 Set_Has_Primitive_Operations (B_Typ);
10291 Check_Private_Overriding (B_Typ);
10293 -- The Ghost policy in effect at the point of declaration
10294 -- of a tagged type and a primitive operation must match
10295 -- (SPARK RM 6.9(16)).
10297 Check_Ghost_Primitive (S, B_Typ);
10300 Next_Formal (Formal);
10303 -- Special case: An equality function can be redefined for a type
10304 -- occurring in a declarative part, and won't otherwise be treated as
10305 -- a primitive because it doesn't occur in a package spec and doesn't
10306 -- override an inherited subprogram. It's important that we mark it
10307 -- primitive so it can be returned by Collect_Primitive_Operations
10308 -- and be used in composing the equality operation of later types
10309 -- that have a component of the type.
10311 elsif Chars (S) = Name_Op_Eq
10312 and then Etype (S) = Standard_Boolean
10314 B_Typ := Base_Type (Etype (First_Formal (S)));
10316 if Scope (B_Typ) = Current_Scope
10318 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10319 and then not Is_Limited_Type (B_Typ)
10321 Is_Primitive := True;
10322 Set_Is_Primitive (S);
10323 Set_Has_Primitive_Operations (B_Typ);
10324 Check_Private_Overriding (B_Typ);
10326 -- The Ghost policy in effect at the point of declaration of a
10327 -- tagged type and a primitive operation must match
10328 -- (SPARK RM 6.9(16)).
10330 Check_Ghost_Primitive (S, B_Typ);
10333 end Check_For_Primitive_Subprogram;
10335 --------------------------------------
10336 -- Has_Matching_Entry_Or_Subprogram --
10337 --------------------------------------
10339 function Has_Matching_Entry_Or_Subprogram
10340 (E : Entity_Id) return Boolean
10342 function Check_Conforming_Parameters
10343 (E1_Param : Node_Id;
10344 E2_Param : Node_Id) return Boolean;
10345 -- Starting from the given parameters, check that all the parameters
10346 -- of two entries or subprograms are subtype conformant. Used to skip
10347 -- the check on the controlling argument.
10349 function Matching_Entry_Or_Subprogram
10350 (Conc_Typ : Entity_Id;
10351 Subp : Entity_Id) return Entity_Id;
10352 -- Return the first entry or subprogram of the given concurrent type
10353 -- whose name matches the name of Subp and has a profile conformant
10354 -- with Subp; return Empty if not found.
10356 function Matching_Dispatching_Subprogram
10357 (Conc_Typ : Entity_Id;
10358 Ent : Entity_Id) return Entity_Id;
10359 -- Return the first dispatching primitive of Conc_Type defined in the
10360 -- enclosing scope of Conc_Type (i.e. before the full definition of
10361 -- this concurrent type) whose name matches the entry Ent and has a
10362 -- profile conformant with the profile of the corresponding (not yet
10363 -- built) dispatching primitive of Ent; return Empty if not found.
10365 function Matching_Original_Protected_Subprogram
10366 (Prot_Typ : Entity_Id;
10367 Subp : Entity_Id) return Entity_Id;
10368 -- Return the first subprogram defined in the enclosing scope of
10369 -- Prot_Typ (before the full definition of this protected type)
10370 -- whose name matches the original name of Subp and has a profile
10371 -- conformant with the profile of Subp; return Empty if not found.
10373 ---------------------------------
10374 -- Check_Conforming_Parameters --
10375 ---------------------------------
10377 function Check_Conforming_Parameters
10378 (E1_Param : Node_Id;
10379 E2_Param : Node_Id) return Boolean
10381 Param_E1 : Node_Id := E1_Param;
10382 Param_E2 : Node_Id := E2_Param;
10385 while Present (Param_E1) and then Present (Param_E2) loop
10386 if Ekind (Defining_Identifier (Param_E1)) /=
10387 Ekind (Defining_Identifier (Param_E2))
10390 (Find_Parameter_Type (Param_E1),
10391 Find_Parameter_Type (Param_E2),
10392 Subtype_Conformant)
10401 -- The candidate is not valid if one of the two lists contains
10402 -- more parameters than the other
10404 return No (Param_E1) and then No (Param_E2);
10405 end Check_Conforming_Parameters;
10407 ----------------------------------
10408 -- Matching_Entry_Or_Subprogram --
10409 ----------------------------------
10411 function Matching_Entry_Or_Subprogram
10412 (Conc_Typ : Entity_Id;
10413 Subp : Entity_Id) return Entity_Id
10418 E := First_Entity (Conc_Typ);
10419 while Present (E) loop
10420 if Chars (Subp) = Chars (E)
10421 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10423 Check_Conforming_Parameters
10424 (First (Parameter_Specifications (Parent (E))),
10425 Next (First (Parameter_Specifications (Parent (Subp)))))
10434 end Matching_Entry_Or_Subprogram;
10436 -------------------------------------
10437 -- Matching_Dispatching_Subprogram --
10438 -------------------------------------
10440 function Matching_Dispatching_Subprogram
10441 (Conc_Typ : Entity_Id;
10442 Ent : Entity_Id) return Entity_Id
10447 -- Search for entities in the enclosing scope of this synchonized
10450 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10451 Push_Scope (Scope (Conc_Typ));
10452 E := Current_Entity_In_Scope (Ent);
10455 while Present (E) loop
10456 if Scope (E) = Scope (Conc_Typ)
10457 and then Comes_From_Source (E)
10458 and then Ekind (E) = E_Procedure
10459 and then Present (First_Entity (E))
10460 and then Is_Controlling_Formal (First_Entity (E))
10461 and then Etype (First_Entity (E)) = Conc_Typ
10463 Check_Conforming_Parameters
10464 (First (Parameter_Specifications (Parent (Ent))),
10465 Next (First (Parameter_Specifications (Parent (E)))))
10474 end Matching_Dispatching_Subprogram;
10476 --------------------------------------------
10477 -- Matching_Original_Protected_Subprogram --
10478 --------------------------------------------
10480 function Matching_Original_Protected_Subprogram
10481 (Prot_Typ : Entity_Id;
10482 Subp : Entity_Id) return Entity_Id
10484 ICF : constant Boolean :=
10485 Is_Controlling_Formal (First_Entity (Subp));
10489 -- Temporarily decorate the first parameter of Subp as controlling
10490 -- formal, required to invoke Subtype_Conformant.
10492 Set_Is_Controlling_Formal (First_Entity (Subp));
10495 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10497 while Present (E) loop
10498 if Scope (E) = Scope (Prot_Typ)
10499 and then Comes_From_Source (E)
10500 and then Ekind (Subp) = Ekind (E)
10501 and then Present (First_Entity (E))
10502 and then Is_Controlling_Formal (First_Entity (E))
10503 and then Etype (First_Entity (E)) = Prot_Typ
10504 and then Subtype_Conformant (Subp, E,
10505 Skip_Controlling_Formals => True)
10507 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10514 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10517 end Matching_Original_Protected_Subprogram;
10519 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10522 -- Case 1: E is a subprogram whose first formal is a concurrent type
10523 -- defined in the scope of E that has an entry or subprogram whose
10524 -- profile matches E.
10526 if Comes_From_Source (E)
10527 and then Is_Subprogram (E)
10528 and then Present (First_Entity (E))
10529 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10532 Scope (Corresponding_Concurrent_Type
10533 (Etype (First_Entity (E))))
10536 (Matching_Entry_Or_Subprogram
10537 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10540 Report_Conflict (E,
10541 Matching_Entry_Or_Subprogram
10542 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10547 -- Case 2: E is an internally built dispatching subprogram of a
10548 -- protected type and there is a subprogram defined in the enclosing
10549 -- scope of the protected type that has the original name of E and
10550 -- its profile is conformant with the profile of E. We check the
10551 -- name of the original protected subprogram associated with E since
10552 -- the expander builds dispatching primitives of protected functions
10553 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10555 elsif not Comes_From_Source (E)
10556 and then Is_Subprogram (E)
10557 and then Present (First_Entity (E))
10558 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10559 and then Present (Original_Protected_Subprogram (E))
10562 (Matching_Original_Protected_Subprogram
10563 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10566 Report_Conflict (E,
10567 Matching_Original_Protected_Subprogram
10568 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10572 -- Case 3: E is an entry of a synchronized type and a matching
10573 -- procedure has been previously defined in the enclosing scope
10574 -- of the synchronized type.
10576 elsif Comes_From_Source (E)
10577 and then Ekind (E) = E_Entry
10579 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10581 Report_Conflict (E,
10582 Matching_Dispatching_Subprogram (Current_Scope, E));
10587 end Has_Matching_Entry_Or_Subprogram;
10589 ----------------------------
10590 -- Is_Private_Declaration --
10591 ----------------------------
10593 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10594 Decl : constant Node_Id := Unit_Declaration_Node (E);
10595 Priv_Decls : List_Id;
10598 if Is_Package_Or_Generic_Package (Current_Scope)
10599 and then In_Private_Part (Current_Scope)
10602 Private_Declarations (Package_Specification (Current_Scope));
10604 return In_Package_Body (Current_Scope)
10606 (Is_List_Member (Decl)
10607 and then List_Containing (Decl) = Priv_Decls)
10608 or else (Nkind (Parent (Decl)) = N_Package_Specification
10610 Is_Compilation_Unit
10611 (Defining_Entity (Parent (Decl)))
10612 and then List_Containing (Parent (Parent (Decl))) =
10617 end Is_Private_Declaration;
10619 --------------------------
10620 -- Is_Overriding_Alias --
10621 --------------------------
10623 function Is_Overriding_Alias
10624 (Old_E : Entity_Id;
10625 New_E : Entity_Id) return Boolean
10627 AO : constant Entity_Id := Alias (Old_E);
10628 AN : constant Entity_Id := Alias (New_E);
10631 return Scope (AO) /= Scope (AN)
10632 or else No (DTC_Entity (AO))
10633 or else No (DTC_Entity (AN))
10634 or else DT_Position (AO) = DT_Position (AN);
10635 end Is_Overriding_Alias;
10637 ---------------------
10638 -- Report_Conflict --
10639 ---------------------
10641 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10643 Error_Msg_Sloc := Sloc (E);
10645 -- Generate message, with useful additional warning if in generic
10647 if Is_Generic_Unit (E) then
10648 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10649 Error_Msg_N ("\& conflicts with declaration#", S);
10651 Error_Msg_N ("& conflicts with declaration#", S);
10653 end Report_Conflict;
10655 -- Start of processing for New_Overloaded_Entity
10658 -- We need to look for an entity that S may override. This must be a
10659 -- homonym in the current scope, so we look for the first homonym of
10660 -- S in the current scope as the starting point for the search.
10662 E := Current_Entity_In_Scope (S);
10664 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10665 -- They are directly added to the list of primitive operations of
10666 -- Derived_Type, unless this is a rederivation in the private part
10667 -- of an operation that was already derived in the visible part of
10668 -- the current package.
10670 if Ada_Version >= Ada_2005
10671 and then Present (Derived_Type)
10672 and then Present (Alias (S))
10673 and then Is_Dispatching_Operation (Alias (S))
10674 and then Present (Find_Dispatching_Type (Alias (S)))
10675 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10677 -- For private types, when the full-view is processed we propagate to
10678 -- the full view the non-overridden entities whose attribute "alias"
10679 -- references an interface primitive. These entities were added by
10680 -- Derive_Subprograms to ensure that interface primitives are
10683 -- Inside_Freeze_Actions is non zero when S corresponds with an
10684 -- internal entity that links an interface primitive with its
10685 -- covering primitive through attribute Interface_Alias (see
10686 -- Add_Internal_Interface_Entities).
10688 if Inside_Freezing_Actions = 0
10689 and then Is_Package_Or_Generic_Package (Current_Scope)
10690 and then In_Private_Part (Current_Scope)
10691 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10692 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10693 and then Full_View (Defining_Identifier (Parent (E)))
10694 = Defining_Identifier (Parent (S))
10695 and then Alias (E) = Alias (S)
10697 Check_Operation_From_Private_View (S, E);
10698 Set_Is_Dispatching_Operation (S);
10703 Enter_Overloaded_Entity (S);
10704 Check_Dispatching_Operation (S, Empty);
10705 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10711 -- For synchronized types check conflicts of this entity with previously
10712 -- defined entities.
10714 if Ada_Version >= Ada_2005
10715 and then Has_Matching_Entry_Or_Subprogram (S)
10720 -- If there is no homonym then this is definitely not overriding
10723 Enter_Overloaded_Entity (S);
10724 Check_Dispatching_Operation (S, Empty);
10725 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10727 -- If subprogram has an explicit declaration, check whether it has an
10728 -- overriding indicator.
10730 if Comes_From_Source (S) then
10731 Check_Synchronized_Overriding (S, Overridden_Subp);
10733 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10734 -- it may have overridden some hidden inherited primitive. Update
10735 -- Overridden_Subp to avoid spurious errors when checking the
10736 -- overriding indicator.
10738 if Ada_Version >= Ada_2012
10739 and then No (Overridden_Subp)
10740 and then Is_Dispatching_Operation (S)
10741 and then Present (Overridden_Operation (S))
10743 Overridden_Subp := Overridden_Operation (S);
10746 Check_Overriding_Indicator
10747 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10749 -- The Ghost policy in effect at the point of declaration of a
10750 -- parent subprogram and an overriding subprogram must match
10751 -- (SPARK RM 6.9(17)).
10753 Check_Ghost_Overriding (S, Overridden_Subp);
10756 -- If there is a homonym that is not overloadable, then we have an
10757 -- error, except for the special cases checked explicitly below.
10759 elsif not Is_Overloadable (E) then
10761 -- Check for spurious conflict produced by a subprogram that has the
10762 -- same name as that of the enclosing generic package. The conflict
10763 -- occurs within an instance, between the subprogram and the renaming
10764 -- declaration for the package. After the subprogram, the package
10765 -- renaming declaration becomes hidden.
10767 if Ekind (E) = E_Package
10768 and then Present (Renamed_Object (E))
10769 and then Renamed_Object (E) = Current_Scope
10770 and then Nkind (Parent (Renamed_Object (E))) =
10771 N_Package_Specification
10772 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10775 Set_Is_Immediately_Visible (E, False);
10776 Enter_Overloaded_Entity (S);
10777 Set_Homonym (S, Homonym (E));
10778 Check_Dispatching_Operation (S, Empty);
10779 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10781 -- If the subprogram is implicit it is hidden by the previous
10782 -- declaration. However if it is dispatching, it must appear in the
10783 -- dispatch table anyway, because it can be dispatched to even if it
10784 -- cannot be called directly.
10786 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10787 Set_Scope (S, Current_Scope);
10789 if Is_Dispatching_Operation (Alias (S)) then
10790 Check_Dispatching_Operation (S, Empty);
10796 Report_Conflict (S, E);
10800 -- E exists and is overloadable
10803 Check_Synchronized_Overriding (S, Overridden_Subp);
10805 -- Loop through E and its homonyms to determine if any of them is
10806 -- the candidate for overriding by S.
10808 while Present (E) loop
10810 -- Definitely not interesting if not in the current scope
10812 if Scope (E) /= Current_Scope then
10815 -- A function can overload the name of an abstract state. The
10816 -- state can be viewed as a function with a profile that cannot
10817 -- be matched by anything.
10819 elsif Ekind (S) = E_Function
10820 and then Ekind (E) = E_Abstract_State
10822 Enter_Overloaded_Entity (S);
10825 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10826 -- procedures locate the internally generated spec. We enforce
10827 -- mode conformance since a tagged type may inherit from
10828 -- interfaces several null primitives which differ only in
10829 -- the mode of the formals.
10831 elsif not Comes_From_Source (S)
10832 and then Is_Null_Procedure (S)
10833 and then not Mode_Conformant (E, S)
10837 -- Check if we have type conformance
10839 elsif Type_Conformant (E, S) then
10841 -- If the old and new entities have the same profile and one
10842 -- is not the body of the other, then this is an error, unless
10843 -- one of them is implicitly declared.
10845 -- There are some cases when both can be implicit, for example
10846 -- when both a literal and a function that overrides it are
10847 -- inherited in a derivation, or when an inherited operation
10848 -- of a tagged full type overrides the inherited operation of
10849 -- a private extension. Ada 83 had a special rule for the
10850 -- literal case. In Ada 95, the later implicit operation hides
10851 -- the former, and the literal is always the former. In the
10852 -- odd case where both are derived operations declared at the
10853 -- same point, both operations should be declared, and in that
10854 -- case we bypass the following test and proceed to the next
10855 -- part. This can only occur for certain obscure cases in
10856 -- instances, when an operation on a type derived from a formal
10857 -- private type does not override a homograph inherited from
10858 -- the actual. In subsequent derivations of such a type, the
10859 -- DT positions of these operations remain distinct, if they
10862 if Present (Alias (S))
10863 and then (No (Alias (E))
10864 or else Comes_From_Source (E)
10865 or else Is_Abstract_Subprogram (S)
10867 (Is_Dispatching_Operation (E)
10868 and then Is_Overriding_Alias (E, S)))
10869 and then Ekind (E) /= E_Enumeration_Literal
10871 -- When an derived operation is overloaded it may be due to
10872 -- the fact that the full view of a private extension
10873 -- re-inherits. It has to be dealt with.
10875 if Is_Package_Or_Generic_Package (Current_Scope)
10876 and then In_Private_Part (Current_Scope)
10878 Check_Operation_From_Private_View (S, E);
10881 -- In any case the implicit operation remains hidden by the
10882 -- existing declaration, which is overriding. Indicate that
10883 -- E overrides the operation from which S is inherited.
10885 if Present (Alias (S)) then
10886 Set_Overridden_Operation (E, Alias (S));
10887 Inherit_Subprogram_Contract (E, Alias (S));
10890 Set_Overridden_Operation (E, S);
10891 Inherit_Subprogram_Contract (E, S);
10894 if Comes_From_Source (E) then
10895 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10897 -- The Ghost policy in effect at the point of declaration
10898 -- of a parent subprogram and an overriding subprogram
10899 -- must match (SPARK RM 6.9(17)).
10901 Check_Ghost_Overriding (E, S);
10906 -- Within an instance, the renaming declarations for actual
10907 -- subprograms may become ambiguous, but they do not hide each
10910 elsif Ekind (E) /= E_Entry
10911 and then not Comes_From_Source (E)
10912 and then not Is_Generic_Instance (E)
10913 and then (Present (Alias (E))
10914 or else Is_Intrinsic_Subprogram (E))
10915 and then (not In_Instance
10916 or else No (Parent (E))
10917 or else Nkind (Unit_Declaration_Node (E)) /=
10918 N_Subprogram_Renaming_Declaration)
10920 -- A subprogram child unit is not allowed to override an
10921 -- inherited subprogram (10.1.1(20)).
10923 if Is_Child_Unit (S) then
10925 ("child unit overrides inherited subprogram in parent",
10930 if Is_Non_Overriding_Operation (E, S) then
10931 Enter_Overloaded_Entity (S);
10933 if No (Derived_Type)
10934 or else Is_Tagged_Type (Derived_Type)
10936 Check_Dispatching_Operation (S, Empty);
10942 -- E is a derived operation or an internal operator which
10943 -- is being overridden. Remove E from further visibility.
10944 -- Furthermore, if E is a dispatching operation, it must be
10945 -- replaced in the list of primitive operations of its type
10946 -- (see Override_Dispatching_Operation).
10948 Overridden_Subp := E;
10950 -- It is possible for E to be in the current scope and
10951 -- yet not in the entity chain. This can only occur in a
10952 -- generic context where E is an implicit concatenation
10953 -- in the formal part, because in a generic body the
10954 -- entity chain starts with the formals.
10956 -- In GNATprove mode, a wrapper for an operation with
10957 -- axiomatization may be a homonym of another declaration
10958 -- for an actual subprogram (needs refinement ???).
10960 if No (Prev_Entity (E)) then
10962 and then GNATprove_Mode
10964 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10965 N_Subprogram_Renaming_Declaration
10969 pragma Assert (Chars (E) = Name_Op_Concat);
10974 -- E must be removed both from the entity_list of the
10975 -- current scope, and from the visibility chain.
10977 if Debug_Flag_E then
10978 Write_Str ("Override implicit operation ");
10979 Write_Int (Int (E));
10983 -- If E is a predefined concatenation, it stands for four
10984 -- different operations. As a result, a single explicit
10985 -- declaration does not hide it. In a possible ambiguous
10986 -- situation, Disambiguate chooses the user-defined op,
10987 -- so it is correct to retain the previous internal one.
10989 if Chars (E) /= Name_Op_Concat
10990 or else Ekind (E) /= E_Operator
10992 -- For nondispatching derived operations that are
10993 -- overridden by a subprogram declared in the private
10994 -- part of a package, we retain the derived subprogram
10995 -- but mark it as not immediately visible. If the
10996 -- derived operation was declared in the visible part
10997 -- then this ensures that it will still be visible
10998 -- outside the package with the proper signature
10999 -- (calls from outside must also be directed to this
11000 -- version rather than the overriding one, unlike the
11001 -- dispatching case). Calls from inside the package
11002 -- will still resolve to the overriding subprogram
11003 -- since the derived one is marked as not visible
11004 -- within the package.
11006 -- If the private operation is dispatching, we achieve
11007 -- the overriding by keeping the implicit operation
11008 -- but setting its alias to be the overriding one. In
11009 -- this fashion the proper body is executed in all
11010 -- cases, but the original signature is used outside
11013 -- If the overriding is not in the private part, we
11014 -- remove the implicit operation altogether.
11016 if Is_Private_Declaration (S) then
11017 if not Is_Dispatching_Operation (E) then
11018 Set_Is_Immediately_Visible (E, False);
11020 -- Work done in Override_Dispatching_Operation, so
11021 -- nothing else needs to be done here.
11027 Remove_Entity_And_Homonym (E);
11031 Enter_Overloaded_Entity (S);
11033 -- For entities generated by Derive_Subprograms the
11034 -- overridden operation is the inherited primitive
11035 -- (which is available through the attribute alias).
11037 if not (Comes_From_Source (E))
11038 and then Is_Dispatching_Operation (E)
11039 and then Find_Dispatching_Type (E) =
11040 Find_Dispatching_Type (S)
11041 and then Present (Alias (E))
11042 and then Comes_From_Source (Alias (E))
11044 Set_Overridden_Operation (S, Alias (E));
11045 Inherit_Subprogram_Contract (S, Alias (E));
11047 -- Normal case of setting entity as overridden
11049 -- Note: Static_Initialization and Overridden_Operation
11050 -- attributes use the same field in subprogram entities.
11051 -- Static_Initialization is only defined for internal
11052 -- initialization procedures, where Overridden_Operation
11053 -- is irrelevant. Therefore the setting of this attribute
11054 -- must check whether the target is an init_proc.
11056 elsif not Is_Init_Proc (S) then
11057 Set_Overridden_Operation (S, E);
11058 Inherit_Subprogram_Contract (S, E);
11061 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11063 -- The Ghost policy in effect at the point of declaration
11064 -- of a parent subprogram and an overriding subprogram
11065 -- must match (SPARK RM 6.9(17)).
11067 Check_Ghost_Overriding (S, E);
11069 -- If S is a user-defined subprogram or a null procedure
11070 -- expanded to override an inherited null procedure, or a
11071 -- predefined dispatching primitive then indicate that E
11072 -- overrides the operation from which S is inherited.
11074 if Comes_From_Source (S)
11076 (Present (Parent (S))
11077 and then Nkind (Parent (S)) = N_Procedure_Specification
11078 and then Null_Present (Parent (S)))
11080 (Present (Alias (E))
11082 Is_Predefined_Dispatching_Operation (Alias (E)))
11084 if Present (Alias (E)) then
11085 Set_Overridden_Operation (S, Alias (E));
11086 Inherit_Subprogram_Contract (S, Alias (E));
11090 if Is_Dispatching_Operation (E) then
11092 -- An overriding dispatching subprogram inherits the
11093 -- convention of the overridden subprogram (AI-117).
11095 Set_Convention (S, Convention (E));
11096 Check_Dispatching_Operation (S, E);
11099 Check_Dispatching_Operation (S, Empty);
11102 Check_For_Primitive_Subprogram
11103 (Is_Primitive_Subp, Is_Overriding => True);
11104 goto Check_Inequality;
11106 -- Apparent redeclarations in instances can occur when two
11107 -- formal types get the same actual type. The subprograms in
11108 -- in the instance are legal, even if not callable from the
11109 -- outside. Calls from within are disambiguated elsewhere.
11110 -- For dispatching operations in the visible part, the usual
11111 -- rules apply, and operations with the same profile are not
11112 -- legal (B830001).
11114 elsif (In_Instance_Visible_Part
11115 and then not Is_Dispatching_Operation (E))
11116 or else In_Instance_Not_Visible
11120 -- Here we have a real error (identical profile)
11123 Error_Msg_Sloc := Sloc (E);
11125 -- Avoid cascaded errors if the entity appears in
11126 -- subsequent calls.
11128 Set_Scope (S, Current_Scope);
11130 -- Generate error, with extra useful warning for the case
11131 -- of a generic instance with no completion.
11133 if Is_Generic_Instance (S)
11134 and then not Has_Completion (E)
11137 ("instantiation cannot provide body for&", S);
11138 Error_Msg_N ("\& conflicts with declaration#", S);
11140 Error_Msg_N ("& conflicts with declaration#", S);
11147 -- If one subprogram has an access parameter and the other
11148 -- a parameter of an access type, calls to either might be
11149 -- ambiguous. Verify that parameters match except for the
11150 -- access parameter.
11152 if May_Hide_Profile then
11158 F1 := First_Formal (S);
11159 F2 := First_Formal (E);
11160 while Present (F1) and then Present (F2) loop
11161 if Is_Access_Type (Etype (F1)) then
11162 if not Is_Access_Type (Etype (F2))
11163 or else not Conforming_Types
11164 (Designated_Type (Etype (F1)),
11165 Designated_Type (Etype (F2)),
11168 May_Hide_Profile := False;
11172 not Conforming_Types
11173 (Etype (F1), Etype (F2), Type_Conformant)
11175 May_Hide_Profile := False;
11182 if May_Hide_Profile
11186 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11195 -- On exit, we know that S is a new entity
11197 Enter_Overloaded_Entity (S);
11198 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11199 Check_Overriding_Indicator
11200 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11202 -- The Ghost policy in effect at the point of declaration of a parent
11203 -- subprogram and an overriding subprogram must match
11204 -- (SPARK RM 6.9(17)).
11206 Check_Ghost_Overriding (S, Overridden_Subp);
11208 -- Overloading is not allowed in SPARK, except for operators
11210 if Nkind (S) /= N_Defining_Operator_Symbol then
11211 Error_Msg_Sloc := Sloc (Homonym (S));
11212 Check_SPARK_05_Restriction
11213 ("overloading not allowed with entity#", S);
11216 -- If S is a derived operation for an untagged type then by
11217 -- definition it's not a dispatching operation (even if the parent
11218 -- operation was dispatching), so Check_Dispatching_Operation is not
11219 -- called in that case.
11221 if No (Derived_Type)
11222 or else Is_Tagged_Type (Derived_Type)
11224 Check_Dispatching_Operation (S, Empty);
11228 -- If this is a user-defined equality operator that is not a derived
11229 -- subprogram, create the corresponding inequality. If the operation is
11230 -- dispatching, the expansion is done elsewhere, and we do not create
11231 -- an explicit inequality operation.
11233 <<Check_Inequality>>
11234 if Chars (S) = Name_Op_Eq
11235 and then Etype (S) = Standard_Boolean
11236 and then Present (Parent (S))
11237 and then not Is_Dispatching_Operation (S)
11239 Make_Inequality_Operator (S);
11240 Check_Untagged_Equality (S);
11242 end New_Overloaded_Entity;
11244 ----------------------------------
11245 -- Preanalyze_Formal_Expression --
11246 ----------------------------------
11248 procedure Preanalyze_Formal_Expression (N : Node_Id; T : Entity_Id) is
11249 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
11251 In_Spec_Expression := True;
11252 Preanalyze_With_Freezing_And_Resolve (N, T);
11253 In_Spec_Expression := Save_In_Spec_Expression;
11254 end Preanalyze_Formal_Expression;
11256 ---------------------
11257 -- Process_Formals --
11258 ---------------------
11260 procedure Process_Formals
11262 Related_Nod : Node_Id)
11264 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11265 -- Determine whether an access type designates a type coming from a
11268 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11269 -- Check whether the default has a class-wide type. After analysis the
11270 -- default has the type of the formal, so we must also check explicitly
11271 -- for an access attribute.
11273 ----------------------------------
11274 -- Designates_From_Limited_With --
11275 ----------------------------------
11277 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11278 Desig : Entity_Id := Typ;
11281 if Is_Access_Type (Desig) then
11282 Desig := Directly_Designated_Type (Desig);
11285 if Is_Class_Wide_Type (Desig) then
11286 Desig := Root_Type (Desig);
11290 Ekind (Desig) = E_Incomplete_Type
11291 and then From_Limited_With (Desig);
11292 end Designates_From_Limited_With;
11294 ---------------------------
11295 -- Is_Class_Wide_Default --
11296 ---------------------------
11298 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11300 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11301 or else (Nkind (D) = N_Attribute_Reference
11302 and then Attribute_Name (D) = Name_Access
11303 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11304 end Is_Class_Wide_Default;
11308 Context : constant Node_Id := Parent (Parent (T));
11310 Formal : Entity_Id;
11311 Formal_Type : Entity_Id;
11312 Param_Spec : Node_Id;
11315 Num_Out_Params : Nat := 0;
11316 First_Out_Param : Entity_Id := Empty;
11317 -- Used for setting Is_Only_Out_Parameter
11319 -- Start of processing for Process_Formals
11322 -- In order to prevent premature use of the formals in the same formal
11323 -- part, the Ekind is left undefined until all default expressions are
11324 -- analyzed. The Ekind is established in a separate loop at the end.
11326 Param_Spec := First (T);
11327 while Present (Param_Spec) loop
11328 Formal := Defining_Identifier (Param_Spec);
11329 Set_Never_Set_In_Source (Formal, True);
11330 Enter_Name (Formal);
11332 -- Case of ordinary parameters
11334 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11335 Find_Type (Parameter_Type (Param_Spec));
11336 Ptype := Parameter_Type (Param_Spec);
11338 if Ptype = Error then
11342 Formal_Type := Entity (Ptype);
11344 if Is_Incomplete_Type (Formal_Type)
11346 (Is_Class_Wide_Type (Formal_Type)
11347 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11349 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11350 -- primitive operations, as long as their completion is
11351 -- in the same declarative part. If in the private part
11352 -- this means that the type cannot be a Taft-amendment type.
11353 -- Check is done on package exit. For access to subprograms,
11354 -- the use is legal for Taft-amendment types.
11356 -- Ada 2012: tagged incomplete types are allowed as generic
11357 -- formal types. They do not introduce dependencies and the
11358 -- corresponding generic subprogram does not have a delayed
11359 -- freeze, because it does not need a freeze node. However,
11360 -- it is still the case that untagged incomplete types cannot
11361 -- be Taft-amendment types and must be completed in private
11362 -- part, so the subprogram must appear in the list of private
11363 -- dependents of the type.
11365 if Is_Tagged_Type (Formal_Type)
11366 or else (Ada_Version >= Ada_2012
11367 and then not From_Limited_With (Formal_Type)
11368 and then not Is_Generic_Type (Formal_Type))
11370 if Ekind (Scope (Current_Scope)) = E_Package
11371 and then not Is_Generic_Type (Formal_Type)
11372 and then not Is_Class_Wide_Type (Formal_Type)
11375 (Parent (T), N_Access_Function_Definition,
11376 N_Access_Procedure_Definition)
11378 Append_Elmt (Current_Scope,
11379 Private_Dependents (Base_Type (Formal_Type)));
11381 -- Freezing is delayed to ensure that Register_Prim
11382 -- will get called for this operation, which is needed
11383 -- in cases where static dispatch tables aren't built.
11384 -- (Note that the same is done for controlling access
11385 -- parameter cases in function Access_Definition.)
11387 if not Is_Thunk (Current_Scope) then
11388 Set_Has_Delayed_Freeze (Current_Scope);
11393 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11394 N_Access_Procedure_Definition)
11396 -- AI05-0151: Tagged incomplete types are allowed in all
11397 -- formal parts. Untagged incomplete types are not allowed
11398 -- in bodies. Limited views of either kind are not allowed
11399 -- if there is no place at which the non-limited view can
11400 -- become available.
11402 -- Incomplete formal untagged types are not allowed in
11403 -- subprogram bodies (but are legal in their declarations).
11404 -- This excludes bodies created for null procedures, which
11405 -- are basic declarations.
11407 if Is_Generic_Type (Formal_Type)
11408 and then not Is_Tagged_Type (Formal_Type)
11409 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11412 ("invalid use of formal incomplete type", Param_Spec);
11414 elsif Ada_Version >= Ada_2012 then
11415 if Is_Tagged_Type (Formal_Type)
11416 and then (not From_Limited_With (Formal_Type)
11417 or else not In_Package_Body)
11421 elsif Nkind_In (Context, N_Accept_Statement,
11422 N_Accept_Alternative,
11424 or else (Nkind (Context) = N_Subprogram_Body
11425 and then Comes_From_Source (Context))
11428 ("invalid use of untagged incomplete type &",
11429 Ptype, Formal_Type);
11434 ("invalid use of incomplete type&",
11435 Param_Spec, Formal_Type);
11437 -- Further checks on the legality of incomplete types
11438 -- in formal parts are delayed until the freeze point
11439 -- of the enclosing subprogram or access to subprogram.
11443 elsif Ekind (Formal_Type) = E_Void then
11445 ("premature use of&",
11446 Parameter_Type (Param_Spec), Formal_Type);
11449 -- Ada 2012 (AI-142): Handle aliased parameters
11451 if Ada_Version >= Ada_2012
11452 and then Aliased_Present (Param_Spec)
11454 Set_Is_Aliased (Formal);
11457 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11458 -- declaration corresponding to the null-excluding type of the
11459 -- formal in the enclosing scope. Finally, replace the parameter
11460 -- type of the formal with the internal subtype.
11462 if Ada_Version >= Ada_2005
11463 and then Null_Exclusion_Present (Param_Spec)
11465 if not Is_Access_Type (Formal_Type) then
11467 ("`NOT NULL` allowed only for an access type", Param_Spec);
11470 if Can_Never_Be_Null (Formal_Type)
11471 and then Comes_From_Source (Related_Nod)
11474 ("`NOT NULL` not allowed (& already excludes null)",
11475 Param_Spec, Formal_Type);
11479 Create_Null_Excluding_Itype
11481 Related_Nod => Related_Nod,
11482 Scope_Id => Scope (Current_Scope));
11484 -- If the designated type of the itype is an itype that is
11485 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11486 -- on the access subtype, to prevent order-of-elaboration
11487 -- issues in the backend.
11490 -- type T is access procedure;
11491 -- procedure Op (O : not null T);
11493 if Is_Itype (Directly_Designated_Type (Formal_Type))
11495 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11497 Set_Has_Delayed_Freeze (Formal_Type);
11502 -- An access formal type
11506 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11508 -- No need to continue if we already notified errors
11510 if not Present (Formal_Type) then
11514 -- Ada 2005 (AI-254)
11517 AD : constant Node_Id :=
11518 Access_To_Subprogram_Definition
11519 (Parameter_Type (Param_Spec));
11521 if Present (AD) and then Protected_Present (AD) then
11523 Replace_Anonymous_Access_To_Protected_Subprogram
11529 Set_Etype (Formal, Formal_Type);
11531 -- Deal with default expression if present
11533 Default := Expression (Param_Spec);
11535 if Present (Default) then
11536 Check_SPARK_05_Restriction
11537 ("default expression is not allowed", Default);
11539 if Out_Present (Param_Spec) then
11541 ("default initialization only allowed for IN parameters",
11545 -- Do the special preanalysis of the expression (see section on
11546 -- "Handling of Default Expressions" in the spec of package Sem).
11548 Preanalyze_Formal_Expression (Default, Formal_Type);
11550 -- An access to constant cannot be the default for
11551 -- an access parameter that is an access to variable.
11553 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11554 and then not Is_Access_Constant (Formal_Type)
11555 and then Is_Access_Type (Etype (Default))
11556 and then Is_Access_Constant (Etype (Default))
11559 ("formal that is access to variable cannot be initialized "
11560 & "with an access-to-constant expression", Default);
11563 -- Check that the designated type of an access parameter's default
11564 -- is not a class-wide type unless the parameter's designated type
11565 -- is also class-wide.
11567 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11568 and then not Designates_From_Limited_With (Formal_Type)
11569 and then Is_Class_Wide_Default (Default)
11570 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11573 ("access to class-wide expression not allowed here", Default);
11576 -- Check incorrect use of dynamically tagged expressions
11578 if Is_Tagged_Type (Formal_Type) then
11579 Check_Dynamically_Tagged_Expression
11581 Typ => Formal_Type,
11582 Related_Nod => Default);
11586 -- Ada 2005 (AI-231): Static checks
11588 if Ada_Version >= Ada_2005
11589 and then Is_Access_Type (Etype (Formal))
11590 and then Can_Never_Be_Null (Etype (Formal))
11592 Null_Exclusion_Static_Checks (Param_Spec);
11595 -- The following checks are relevant only when SPARK_Mode is on as
11596 -- these are not standard Ada legality rules.
11598 if SPARK_Mode = On then
11599 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11601 -- A function cannot have a parameter of mode IN OUT or OUT
11604 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11606 ("function cannot have parameter of mode `OUT` or "
11607 & "`IN OUT`", Formal);
11610 -- A procedure cannot have an effectively volatile formal
11611 -- parameter of mode IN because it behaves as a constant
11612 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11614 elsif Ekind (Scope (Formal)) = E_Procedure
11615 and then Ekind (Formal) = E_In_Parameter
11616 and then Is_Effectively_Volatile (Formal)
11619 ("formal parameter of mode `IN` cannot be volatile", Formal);
11627 -- If this is the formal part of a function specification, analyze the
11628 -- subtype mark in the context where the formals are visible but not
11629 -- yet usable, and may hide outer homographs.
11631 if Nkind (Related_Nod) = N_Function_Specification then
11632 Analyze_Return_Type (Related_Nod);
11635 -- Now set the kind (mode) of each formal
11637 Param_Spec := First (T);
11638 while Present (Param_Spec) loop
11639 Formal := Defining_Identifier (Param_Spec);
11640 Set_Formal_Mode (Formal);
11642 if Ekind (Formal) = E_In_Parameter then
11643 Set_Default_Value (Formal, Expression (Param_Spec));
11645 if Present (Expression (Param_Spec)) then
11646 Default := Expression (Param_Spec);
11648 if Is_Scalar_Type (Etype (Default)) then
11649 if Nkind (Parameter_Type (Param_Spec)) /=
11650 N_Access_Definition
11652 Formal_Type := Entity (Parameter_Type (Param_Spec));
11656 (Related_Nod, Parameter_Type (Param_Spec));
11659 Apply_Scalar_Range_Check (Default, Formal_Type);
11663 elsif Ekind (Formal) = E_Out_Parameter then
11664 Num_Out_Params := Num_Out_Params + 1;
11666 if Num_Out_Params = 1 then
11667 First_Out_Param := Formal;
11670 elsif Ekind (Formal) = E_In_Out_Parameter then
11671 Num_Out_Params := Num_Out_Params + 1;
11674 -- Skip remaining processing if formal type was in error
11676 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11677 goto Next_Parameter;
11680 -- Force call by reference if aliased
11683 Conv : constant Convention_Id := Convention (Etype (Formal));
11685 if Is_Aliased (Formal) then
11686 Set_Mechanism (Formal, By_Reference);
11688 -- Warn if user asked this to be passed by copy
11690 if Conv = Convention_Ada_Pass_By_Copy then
11692 ("cannot pass aliased parameter & by copy??", Formal);
11695 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11697 elsif Conv = Convention_Ada_Pass_By_Copy then
11698 Set_Mechanism (Formal, By_Copy);
11700 elsif Conv = Convention_Ada_Pass_By_Reference then
11701 Set_Mechanism (Formal, By_Reference);
11709 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11710 Set_Is_Only_Out_Parameter (First_Out_Param);
11712 end Process_Formals;
11714 ----------------------------
11715 -- Reference_Body_Formals --
11716 ----------------------------
11718 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11723 if Error_Posted (Spec) then
11727 -- Iterate over both lists. They may be of different lengths if the two
11728 -- specs are not conformant.
11730 Fs := First_Formal (Spec);
11731 Fb := First_Formal (Bod);
11732 while Present (Fs) and then Present (Fb) loop
11733 Generate_Reference (Fs, Fb, 'b');
11735 if Style_Check then
11736 Style.Check_Identifier (Fb, Fs);
11739 Set_Spec_Entity (Fb, Fs);
11740 Set_Referenced (Fs, False);
11744 end Reference_Body_Formals;
11746 -------------------------
11747 -- Set_Actual_Subtypes --
11748 -------------------------
11750 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11752 Formal : Entity_Id;
11754 First_Stmt : Node_Id := Empty;
11755 AS_Needed : Boolean;
11758 -- If this is an empty initialization procedure, no need to create
11759 -- actual subtypes (small optimization).
11761 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11764 -- Within a predicate function we do not want to generate local
11765 -- subtypes that may generate nested predicate functions.
11767 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11771 -- The subtype declarations may freeze the formals. The body generated
11772 -- for an expression function is not a freeze point, so do not emit
11773 -- these declarations (small loss of efficiency in rare cases).
11775 if Nkind (N) = N_Subprogram_Body
11776 and then Was_Expression_Function (N)
11781 Formal := First_Formal (Subp);
11782 while Present (Formal) loop
11783 T := Etype (Formal);
11785 -- We never need an actual subtype for a constrained formal
11787 if Is_Constrained (T) then
11788 AS_Needed := False;
11790 -- If we have unknown discriminants, then we do not need an actual
11791 -- subtype, or more accurately we cannot figure it out. Note that
11792 -- all class-wide types have unknown discriminants.
11794 elsif Has_Unknown_Discriminants (T) then
11795 AS_Needed := False;
11797 -- At this stage we have an unconstrained type that may need an
11798 -- actual subtype. For sure the actual subtype is needed if we have
11799 -- an unconstrained array type. However, in an instance, the type
11800 -- may appear as a subtype of the full view, while the actual is
11801 -- in fact private (in which case no actual subtype is needed) so
11802 -- check the kind of the base type.
11804 elsif Is_Array_Type (Base_Type (T)) then
11807 -- The only other case needing an actual subtype is an unconstrained
11808 -- record type which is an IN parameter (we cannot generate actual
11809 -- subtypes for the OUT or IN OUT case, since an assignment can
11810 -- change the discriminant values. However we exclude the case of
11811 -- initialization procedures, since discriminants are handled very
11812 -- specially in this context, see the section entitled "Handling of
11813 -- Discriminants" in Einfo.
11815 -- We also exclude the case of Discrim_SO_Functions (functions used
11816 -- in front-end layout mode for size/offset values), since in such
11817 -- functions only discriminants are referenced, and not only are such
11818 -- subtypes not needed, but they cannot always be generated, because
11819 -- of order of elaboration issues.
11821 elsif Is_Record_Type (T)
11822 and then Ekind (Formal) = E_In_Parameter
11823 and then Chars (Formal) /= Name_uInit
11824 and then not Is_Unchecked_Union (T)
11825 and then not Is_Discrim_SO_Function (Subp)
11829 -- All other cases do not need an actual subtype
11832 AS_Needed := False;
11835 -- Generate actual subtypes for unconstrained arrays and
11836 -- unconstrained discriminated records.
11839 if Nkind (N) = N_Accept_Statement then
11841 -- If expansion is active, the formal is replaced by a local
11842 -- variable that renames the corresponding entry of the
11843 -- parameter block, and it is this local variable that may
11844 -- require an actual subtype.
11846 if Expander_Active then
11847 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11849 Decl := Build_Actual_Subtype (T, Formal);
11852 if Present (Handled_Statement_Sequence (N)) then
11854 First (Statements (Handled_Statement_Sequence (N)));
11855 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11856 Mark_Rewrite_Insertion (Decl);
11858 -- If the accept statement has no body, there will be no
11859 -- reference to the actuals, so no need to compute actual
11866 Decl := Build_Actual_Subtype (T, Formal);
11867 Prepend (Decl, Declarations (N));
11868 Mark_Rewrite_Insertion (Decl);
11871 -- The declaration uses the bounds of an existing object, and
11872 -- therefore needs no constraint checks.
11874 Analyze (Decl, Suppress => All_Checks);
11875 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11877 -- We need to freeze manually the generated type when it is
11878 -- inserted anywhere else than in a declarative part.
11880 if Present (First_Stmt) then
11881 Insert_List_Before_And_Analyze (First_Stmt,
11882 Freeze_Entity (Defining_Identifier (Decl), N));
11884 -- Ditto if the type has a dynamic predicate, because the
11885 -- generated function will mention the actual subtype. The
11886 -- predicate may come from an explicit aspect of be inherited.
11888 elsif Has_Predicates (T) then
11889 Insert_List_Before_And_Analyze (Decl,
11890 Freeze_Entity (Defining_Identifier (Decl), N));
11893 if Nkind (N) = N_Accept_Statement
11894 and then Expander_Active
11896 Set_Actual_Subtype (Renamed_Object (Formal),
11897 Defining_Identifier (Decl));
11899 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11903 Next_Formal (Formal);
11905 end Set_Actual_Subtypes;
11907 ---------------------
11908 -- Set_Formal_Mode --
11909 ---------------------
11911 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11912 Spec : constant Node_Id := Parent (Formal_Id);
11913 Id : constant Entity_Id := Scope (Formal_Id);
11916 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11917 -- since we ensure that corresponding actuals are always valid at the
11918 -- point of the call.
11920 if Out_Present (Spec) then
11921 if Ekind_In (Id, E_Entry, E_Entry_Family)
11922 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11924 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11927 if Ekind_In (Id, E_Function, E_Generic_Function) then
11929 -- [IN] OUT parameters allowed for functions in Ada 2012
11931 if Ada_Version >= Ada_2012 then
11933 -- Even in Ada 2012 operators can only have IN parameters
11935 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11936 Error_Msg_N ("operators can only have IN parameters", Spec);
11939 if In_Present (Spec) then
11940 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11942 Set_Ekind (Formal_Id, E_Out_Parameter);
11945 -- But not in earlier versions of Ada
11948 Error_Msg_N ("functions can only have IN parameters", Spec);
11949 Set_Ekind (Formal_Id, E_In_Parameter);
11952 elsif In_Present (Spec) then
11953 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11956 Set_Ekind (Formal_Id, E_Out_Parameter);
11957 Set_Never_Set_In_Source (Formal_Id, True);
11958 Set_Is_True_Constant (Formal_Id, False);
11959 Set_Current_Value (Formal_Id, Empty);
11963 Set_Ekind (Formal_Id, E_In_Parameter);
11966 -- Set Is_Known_Non_Null for access parameters since the language
11967 -- guarantees that access parameters are always non-null. We also set
11968 -- Can_Never_Be_Null, since there is no way to change the value.
11970 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11972 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11973 -- null; In Ada 2005, only if then null_exclusion is explicit.
11975 if Ada_Version < Ada_2005
11976 or else Can_Never_Be_Null (Etype (Formal_Id))
11978 Set_Is_Known_Non_Null (Formal_Id);
11979 Set_Can_Never_Be_Null (Formal_Id);
11982 -- Ada 2005 (AI-231): Null-exclusion access subtype
11984 elsif Is_Access_Type (Etype (Formal_Id))
11985 and then Can_Never_Be_Null (Etype (Formal_Id))
11987 Set_Is_Known_Non_Null (Formal_Id);
11989 -- We can also set Can_Never_Be_Null (thus preventing some junk
11990 -- access checks) for the case of an IN parameter, which cannot
11991 -- be changed, or for an IN OUT parameter, which can be changed but
11992 -- not to a null value. But for an OUT parameter, the initial value
11993 -- passed in can be null, so we can't set this flag in that case.
11995 if Ekind (Formal_Id) /= E_Out_Parameter then
11996 Set_Can_Never_Be_Null (Formal_Id);
12000 Set_Mechanism (Formal_Id, Default_Mechanism);
12001 Set_Formal_Validity (Formal_Id);
12002 end Set_Formal_Mode;
12004 -------------------------
12005 -- Set_Formal_Validity --
12006 -------------------------
12008 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12010 -- If no validity checking, then we cannot assume anything about the
12011 -- validity of parameters, since we do not know there is any checking
12012 -- of the validity on the call side.
12014 if not Validity_Checks_On then
12017 -- If validity checking for parameters is enabled, this means we are
12018 -- not supposed to make any assumptions about argument values.
12020 elsif Validity_Check_Parameters then
12023 -- If we are checking in parameters, we will assume that the caller is
12024 -- also checking parameters, so we can assume the parameter is valid.
12026 elsif Ekind (Formal_Id) = E_In_Parameter
12027 and then Validity_Check_In_Params
12029 Set_Is_Known_Valid (Formal_Id, True);
12031 -- Similar treatment for IN OUT parameters
12033 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12034 and then Validity_Check_In_Out_Params
12036 Set_Is_Known_Valid (Formal_Id, True);
12038 end Set_Formal_Validity;
12040 ------------------------
12041 -- Subtype_Conformant --
12042 ------------------------
12044 function Subtype_Conformant
12045 (New_Id : Entity_Id;
12046 Old_Id : Entity_Id;
12047 Skip_Controlling_Formals : Boolean := False) return Boolean
12051 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12052 Skip_Controlling_Formals => Skip_Controlling_Formals);
12054 end Subtype_Conformant;
12056 ---------------------
12057 -- Type_Conformant --
12058 ---------------------
12060 function Type_Conformant
12061 (New_Id : Entity_Id;
12062 Old_Id : Entity_Id;
12063 Skip_Controlling_Formals : Boolean := False) return Boolean
12067 May_Hide_Profile := False;
12069 (New_Id, Old_Id, Type_Conformant, False, Result,
12070 Skip_Controlling_Formals => Skip_Controlling_Formals);
12072 end Type_Conformant;
12074 -------------------------------
12075 -- Valid_Operator_Definition --
12076 -------------------------------
12078 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12081 Id : constant Name_Id := Chars (Designator);
12085 F := First_Formal (Designator);
12086 while Present (F) loop
12089 if Present (Default_Value (F)) then
12091 ("default values not allowed for operator parameters",
12094 -- For function instantiations that are operators, we must check
12095 -- separately that the corresponding generic only has in-parameters.
12096 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12097 -- an error could not arise in earlier versions of the language.
12099 elsif Ekind (F) /= E_In_Parameter then
12100 Error_Msg_N ("operators can only have IN parameters", F);
12106 -- Verify that user-defined operators have proper number of arguments
12107 -- First case of operators which can only be unary
12109 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12112 -- Case of operators which can be unary or binary
12114 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12115 N_OK := (N in 1 .. 2);
12117 -- All other operators can only be binary
12125 ("incorrect number of arguments for operator", Designator);
12129 and then Base_Type (Etype (Designator)) = Standard_Boolean
12130 and then not Is_Intrinsic_Subprogram (Designator)
12133 ("explicit definition of inequality not allowed", Designator);
12135 end Valid_Operator_Definition;