1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, 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_Disp; use Exp_Disp;
40 with Exp_Tss; use Exp_Tss;
41 with Exp_Util; use Exp_Util;
42 with Freeze; use Freeze;
43 with Ghost; use Ghost;
44 with Inline; use Inline;
45 with Itypes; use Itypes;
46 with Lib.Xref; use Lib.Xref;
47 with Layout; use Layout;
48 with Namet; use Namet;
50 with Nlists; use Nlists;
51 with Nmake; use Nmake;
53 with Output; use Output;
54 with Restrict; use Restrict;
55 with Rident; use Rident;
56 with Rtsfind; use Rtsfind;
58 with Sem_Aux; use Sem_Aux;
59 with Sem_Cat; use Sem_Cat;
60 with Sem_Ch3; use Sem_Ch3;
61 with Sem_Ch4; use Sem_Ch4;
62 with Sem_Ch5; use Sem_Ch5;
63 with Sem_Ch8; use Sem_Ch8;
64 with Sem_Ch9; use Sem_Ch9;
65 with Sem_Ch10; use Sem_Ch10;
66 with Sem_Ch12; use Sem_Ch12;
67 with Sem_Ch13; use Sem_Ch13;
68 with Sem_Dim; use Sem_Dim;
69 with Sem_Disp; use Sem_Disp;
70 with Sem_Dist; use Sem_Dist;
71 with Sem_Elim; use Sem_Elim;
72 with Sem_Eval; use Sem_Eval;
73 with Sem_Mech; use Sem_Mech;
74 with Sem_Prag; use Sem_Prag;
75 with Sem_Res; use Sem_Res;
76 with Sem_Util; use Sem_Util;
77 with Sem_Type; use Sem_Type;
78 with Sem_Warn; use Sem_Warn;
79 with Sinput; use Sinput;
80 with Stand; use Stand;
81 with Sinfo; use Sinfo;
82 with Sinfo.CN; use Sinfo.CN;
83 with Snames; use Snames;
84 with Stringt; use Stringt;
86 with Stylesw; use Stylesw;
87 with Tbuild; use Tbuild;
88 with Uintp; use Uintp;
89 with Urealp; use Urealp;
90 with Validsw; use Validsw;
92 package body Sem_Ch6 is
94 May_Hide_Profile : Boolean := False;
95 -- This flag is used to indicate that two formals in two subprograms being
96 -- checked for conformance differ only in that one is an access parameter
97 -- while the other is of a general access type with the same designated
98 -- type. In this case, if the rest of the signatures match, a call to
99 -- either subprogram may be ambiguous, which is worth a warning. The flag
100 -- is set in Compatible_Types, and the warning emitted in
101 -- New_Overloaded_Entity.
103 -----------------------
104 -- Local Subprograms --
105 -----------------------
107 procedure Analyze_Function_Return (N : Node_Id);
108 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
109 -- applies to a [generic] function.
111 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
112 -- Analyze a generic subprogram body. N is the body to be analyzed, and
113 -- Gen_Id is the defining entity Id for the corresponding spec.
115 procedure Analyze_Null_Procedure
117 Is_Completion : out Boolean);
118 -- A null procedure can be a declaration or (Ada 2012) a completion
120 procedure Analyze_Return_Statement (N : Node_Id);
121 -- Common processing for simple and extended return statements
123 procedure Analyze_Return_Type (N : Node_Id);
124 -- Subsidiary to Process_Formals: analyze subtype mark in function
125 -- specification in a context where the formals are visible and hide
128 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
129 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
130 -- that we can use RETURN but not skip the debug output at the end.
132 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
133 -- Returns true if Subp can override a predefined operator.
135 procedure Check_Conformance
138 Ctype : Conformance_Type;
140 Conforms : out Boolean;
141 Err_Loc : Node_Id := Empty;
142 Get_Inst : Boolean := False;
143 Skip_Controlling_Formals : Boolean := False);
144 -- Given two entities, this procedure checks that the profiles associated
145 -- with these entities meet the conformance criterion given by the third
146 -- parameter. If they conform, Conforms is set True and control returns
147 -- to the caller. If they do not conform, Conforms is set to False, and
148 -- in addition, if Errmsg is True on the call, proper messages are output
149 -- to complain about the conformance failure. If Err_Loc is non_Empty
150 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
151 -- error messages are placed on the appropriate part of the construct
152 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
153 -- against a formal access-to-subprogram type so Get_Instance_Of must
156 procedure Check_Limited_Return
160 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
161 -- types. Used only for simple return statements. Expr is the expression
164 procedure Check_Subprogram_Order (N : Node_Id);
165 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
166 -- the alpha ordering rule for N if this ordering requirement applicable.
168 procedure Check_Returns
172 Proc : Entity_Id := Empty);
173 -- Called to check for missing return statements in a function body, or for
174 -- returns present in a procedure body which has No_Return set. HSS is the
175 -- handled statement sequence for the subprogram body. This procedure
176 -- checks all flow paths to make sure they either have return (Mode = 'F',
177 -- used for functions) or do not have a return (Mode = 'P', used for
178 -- No_Return procedures). The flag Err is set if there are any control
179 -- paths not explicitly terminated by a return in the function case, and is
180 -- True otherwise. Proc is the entity for the procedure case and is used
181 -- in posting the warning message.
183 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
184 -- In Ada 2012, a primitive equality operator on an untagged record type
185 -- must appear before the type is frozen, and have the same visibility as
186 -- that of the type. This procedure checks that this rule is met, and
187 -- otherwise emits an error on the subprogram declaration and a warning
188 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
189 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
190 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
191 -- is set, otherwise the call has no effect.
193 procedure Enter_Overloaded_Entity (S : Entity_Id);
194 -- This procedure makes S, a new overloaded entity, into the first visible
195 -- entity with that name.
197 function Is_Non_Overriding_Operation
199 New_E : Entity_Id) return Boolean;
200 -- Enforce the rule given in 12.3(18): a private operation in an instance
201 -- overrides an inherited operation only if the corresponding operation
202 -- was overriding in the generic. This needs to be checked for primitive
203 -- operations of types derived (in the generic unit) from formal private
204 -- or formal derived types.
206 procedure Make_Inequality_Operator (S : Entity_Id);
207 -- Create the declaration for an inequality operator that is implicitly
208 -- created by a user-defined equality operator that yields a boolean.
210 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
211 -- Formal_Id is an formal parameter entity. This procedure deals with
212 -- setting the proper validity status for this entity, which depends on
213 -- the kind of parameter and the validity checking mode.
215 ---------------------------------------------
216 -- Analyze_Abstract_Subprogram_Declaration --
217 ---------------------------------------------
219 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
220 Scop : constant Entity_Id := Current_Scope;
221 Subp_Id : constant Entity_Id :=
222 Analyze_Subprogram_Specification (Specification (N));
225 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
227 Generate_Definition (Subp_Id);
229 Set_Is_Abstract_Subprogram (Subp_Id);
230 New_Overloaded_Entity (Subp_Id);
231 Check_Delayed_Subprogram (Subp_Id);
233 Set_Categorization_From_Scope (Subp_Id, Scop);
235 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
236 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
238 -- Issue a warning if the abstract subprogram is neither a dispatching
239 -- operation nor an operation that overrides an inherited subprogram or
240 -- predefined operator, since this most likely indicates a mistake.
242 elsif Warn_On_Redundant_Constructs
243 and then not Is_Dispatching_Operation (Subp_Id)
244 and then not Present (Overridden_Operation (Subp_Id))
245 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
246 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
249 ("abstract subprogram is not dispatching or overriding?r?", N);
252 Generate_Reference_To_Formals (Subp_Id);
253 Check_Eliminated (Subp_Id);
255 if Has_Aspects (N) then
256 Analyze_Aspect_Specifications (N, Subp_Id);
258 end Analyze_Abstract_Subprogram_Declaration;
260 ---------------------------------
261 -- Analyze_Expression_Function --
262 ---------------------------------
264 procedure Analyze_Expression_Function (N : Node_Id) is
265 Expr : constant Node_Id := Expression (N);
266 Loc : constant Source_Ptr := Sloc (N);
267 LocX : constant Source_Ptr := Sloc (Expr);
268 Spec : constant Node_Id := Specification (N);
276 Ret_Type : Entity_Id;
279 -- If the expression is a completion, Prev is the entity whose
280 -- declaration is completed. Def_Id is needed to analyze the spec.
283 -- This is one of the occasions on which we transform the tree during
284 -- semantic analysis. If this is a completion, transform the expression
285 -- function into an equivalent subprogram body, and analyze it.
287 -- Expression functions are inlined unconditionally. The back-end will
288 -- determine whether this is possible.
290 Inline_Processing_Required := True;
292 -- Create a specification for the generated body. This must be done
293 -- prior to the analysis of the initial declaration.
295 New_Spec := Copy_Subprogram_Spec (Spec);
296 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
298 -- If there are previous overloadable entities with the same name,
299 -- check whether any of them is completed by the expression function.
300 -- In a generic context a formal subprogram has no completion.
303 and then Is_Overloadable (Prev)
304 and then not Is_Formal_Subprogram (Prev)
306 Def_Id := Analyze_Subprogram_Specification (Spec);
307 Prev := Find_Corresponding_Spec (N);
309 -- The previous entity may be an expression function as well, in
310 -- which case the redeclaration is illegal.
313 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
314 N_Expression_Function
316 Error_Msg_Sloc := Sloc (Prev);
317 Error_Msg_N ("& conflicts with declaration#", Def_Id);
322 Ret := Make_Simple_Return_Statement (LocX, Expression (N));
325 Make_Subprogram_Body (Loc,
326 Specification => New_Spec,
327 Declarations => Empty_List,
328 Handled_Statement_Sequence =>
329 Make_Handled_Sequence_Of_Statements (LocX,
330 Statements => New_List (Ret)));
331 Set_Was_Expression_Function (New_Body);
333 -- If the expression completes a generic subprogram, we must create a
334 -- separate node for the body, because at instantiation the original
335 -- node of the generic copy must be a generic subprogram body, and
336 -- cannot be a expression function. Otherwise we just rewrite the
337 -- expression with the non-generic body.
339 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
340 Insert_After (N, New_Body);
342 -- Propagate any aspects or pragmas that apply to the expression
343 -- function to the proper body when the expression function acts
346 if Has_Aspects (N) then
347 Move_Aspects (N, To => New_Body);
350 Relocate_Pragmas_To_Body (New_Body);
352 Rewrite (N, Make_Null_Statement (Loc));
353 Set_Has_Completion (Prev, False);
356 Set_Is_Inlined (Prev);
358 -- If the expression function is a completion, the previous declaration
359 -- must come from source. We know already that it appears in the current
360 -- scope. The entity itself may be internally created if within a body
364 and then Comes_From_Source (Parent (Prev))
365 and then not Is_Formal_Subprogram (Prev)
367 Set_Has_Completion (Prev, False);
368 Set_Is_Inlined (Prev);
369 Ret_Type := Etype (Prev);
371 -- An expression function which acts as a completion freezes the
372 -- expression. This means freezing the return type, and if it is
373 -- an access type, freezing its designated type as well.
375 -- Note that we cannot defer this freezing to the analysis of the
376 -- expression itself, because a freeze node might appear in a nested
377 -- scope, leading to an elaboration order issue in gigi.
379 Freeze_Before (N, Ret_Type);
381 -- An entity can only be frozen if it is complete, so if the type
382 -- is still unfrozen it must still be incomplete in some way, e.g.
383 -- a private type without a full view, or a type derived from such
384 -- in an enclosing scope. Except in a generic context (where the
385 -- type may be a generic formal or derived from such), such use of
386 -- an incomplete type is an error. On the other hand, if this is a
387 -- limited view of a type, the type is declared in another unit and
388 -- frozen there. We must be in a context seeing the nonlimited view
389 -- of the type, which will be installed when the body is compiled.
391 if not Is_Frozen (Ret_Type)
392 and then not Is_Generic_Type (Root_Type (Ret_Type))
393 and then not Inside_A_Generic
395 if From_Limited_With (Ret_Type)
396 and then Present (Non_Limited_View (Ret_Type))
401 ("premature use of private type&",
402 Result_Definition (Specification (N)), Ret_Type);
406 -- For navigation purposes, indicate that the function is a body
408 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
409 Rewrite (N, New_Body);
411 -- Remove any existing aspects from the original node because the act
412 -- of rewriting causes the list to be shared between the two nodes.
414 Orig_N := Original_Node (N);
415 Remove_Aspects (Orig_N);
417 -- Propagate any pragmas that apply to expression function to the
418 -- proper body when the expression function acts as a completion.
419 -- Aspects are automatically transfered because of node rewriting.
421 Relocate_Pragmas_To_Body (N);
424 -- Once the aspects of the generated body have been analyzed, create
425 -- a copy for ASIS purposes and associate it with the original node.
427 if Has_Aspects (N) then
428 Set_Aspect_Specifications (Orig_N,
429 New_Copy_List_Tree (Aspect_Specifications (N)));
432 -- Prev is the previous entity with the same name, but it is can
433 -- be an unrelated spec that is not completed by the expression
434 -- function. In that case the relevant entity is the one in the body.
435 -- Not clear that the backend can inline it in this case ???
437 if Has_Completion (Prev) then
439 -- The formals of the expression function are body formals,
440 -- and do not appear in the ali file, which will only contain
441 -- references to the formals of the original subprogram spec.
448 F1 := First_Formal (Def_Id);
449 F2 := First_Formal (Prev);
451 while Present (F1) loop
452 Set_Spec_Entity (F1, F2);
459 Set_Is_Inlined (Defining_Entity (New_Body));
462 -- If this is not a completion, create both a declaration and a body, so
463 -- that the expression can be inlined whenever possible.
466 -- An expression function that is not a completion is not a
467 -- subprogram declaration, and thus cannot appear in a protected
470 if Nkind (Parent (N)) = N_Protected_Definition then
472 ("an expression function is not a legal protected operation", N);
475 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
477 -- Remove any existing aspects from the original node because the act
478 -- of rewriting causes the list to be shared between the two nodes.
480 Orig_N := Original_Node (N);
481 Remove_Aspects (Orig_N);
485 -- Once the aspects of the generated spec have been analyzed, create
486 -- a copy for ASIS purposes and associate it with the original node.
488 if Has_Aspects (N) then
489 Set_Aspect_Specifications (Orig_N,
490 New_Copy_List_Tree (Aspect_Specifications (N)));
493 -- If aspect SPARK_Mode was specified on the body, it needs to be
494 -- repeated both on the generated spec and the body.
496 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
498 if Present (Asp) then
499 Asp := New_Copy_Tree (Asp);
500 Set_Analyzed (Asp, False);
501 Set_Aspect_Specifications (New_Body, New_List (Asp));
504 Def_Id := Defining_Entity (N);
506 -- Within a generic pre-analyze the original expression for name
507 -- capture. The body is also generated but plays no role in
508 -- this because it is not part of the original source.
510 if Inside_A_Generic then
511 Set_Has_Completion (Def_Id);
513 Install_Formals (Def_Id);
514 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
518 Set_Is_Inlined (Defining_Entity (N));
520 -- Establish the linkages between the spec and the body. These are
521 -- used when the expression function acts as the prefix of attribute
522 -- 'Access in order to freeze the original expression which has been
523 -- moved to the generated body.
525 Set_Corresponding_Body (N, Defining_Entity (New_Body));
526 Set_Corresponding_Spec (New_Body, Defining_Entity (N));
528 -- To prevent premature freeze action, insert the new body at the end
529 -- of the current declarations, or at the end of the package spec.
530 -- However, resolve usage names now, to prevent spurious visibility
531 -- on later entities. Note that the function can now be called in
532 -- the current declarative part, which will appear to be prior to
533 -- the presence of the body in the code. There are nevertheless no
534 -- order of elaboration issues because all name resolution has taken
535 -- place at the point of declaration.
538 Decls : List_Id := List_Containing (N);
539 Expr : constant Node_Id := Expression (Ret);
540 Par : constant Node_Id := Parent (Decls);
541 Typ : constant Entity_Id := Etype (Def_Id);
544 -- If this is a wrapper created for in an instance for a formal
545 -- subprogram, insert body after declaration, to be analyzed when
546 -- the enclosing instance is analyzed.
549 and then Is_Generic_Actual_Subprogram (Defining_Entity (N))
551 Insert_After (N, New_Body);
554 if Nkind (Par) = N_Package_Specification
555 and then Decls = Visible_Declarations (Par)
556 and then Present (Private_Declarations (Par))
557 and then not Is_Empty_List (Private_Declarations (Par))
559 Decls := Private_Declarations (Par);
562 Insert_After (Last (Decls), New_Body);
564 -- Preanalyze the expression for name capture, except in an
565 -- instance, where this has been done during generic analysis,
566 -- and will be redone when analyzing the body.
568 Set_Parent (Expr, Ret);
570 Install_Formals (Def_Id);
572 if not In_Instance then
573 Preanalyze_Spec_Expression (Expr, Typ);
574 Check_Limited_Return (Original_Node (N), Expr, Typ);
582 -- If the return expression is a static constant, we suppress warning
583 -- messages on unused formals, which in most cases will be noise.
585 Set_Is_Trivial_Subprogram
586 (Defining_Entity (New_Body), Is_OK_Static_Expression (Expr));
587 end Analyze_Expression_Function;
589 ----------------------------------------
590 -- Analyze_Extended_Return_Statement --
591 ----------------------------------------
593 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
595 Check_Compiler_Unit ("extended return statement", N);
596 Analyze_Return_Statement (N);
597 end Analyze_Extended_Return_Statement;
599 ----------------------------
600 -- Analyze_Function_Call --
601 ----------------------------
603 procedure Analyze_Function_Call (N : Node_Id) is
604 Actuals : constant List_Id := Parameter_Associations (N);
605 Func_Nam : constant Node_Id := Name (N);
611 -- A call of the form A.B (X) may be an Ada 2005 call, which is
612 -- rewritten as B (A, X). If the rewriting is successful, the call
613 -- has been analyzed and we just return.
615 if Nkind (Func_Nam) = N_Selected_Component
616 and then Name (N) /= Func_Nam
617 and then Is_Rewrite_Substitution (N)
618 and then Present (Etype (N))
623 -- If error analyzing name, then set Any_Type as result type and return
625 if Etype (Func_Nam) = Any_Type then
626 Set_Etype (N, Any_Type);
630 -- Otherwise analyze the parameters
632 if Present (Actuals) then
633 Actual := First (Actuals);
634 while Present (Actual) loop
636 Check_Parameterless_Call (Actual);
642 end Analyze_Function_Call;
644 -----------------------------
645 -- Analyze_Function_Return --
646 -----------------------------
648 procedure Analyze_Function_Return (N : Node_Id) is
649 Loc : constant Source_Ptr := Sloc (N);
650 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
651 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
653 R_Type : constant Entity_Id := Etype (Scope_Id);
654 -- Function result subtype
656 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
657 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
658 -- aggregate in a return statement.
660 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
661 -- Check that the return_subtype_indication properly matches the result
662 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
664 -----------------------------------
665 -- Check_Aggregate_Accessibility --
666 -----------------------------------
668 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
669 Typ : constant Entity_Id := Etype (Aggr);
676 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
677 Discr := First_Discriminant (Typ);
678 Assoc := First (Component_Associations (Aggr));
679 while Present (Discr) loop
680 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
681 Expr := Expression (Assoc);
683 if Nkind (Expr) = N_Attribute_Reference
684 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
686 Obj := Prefix (Expr);
687 while Nkind_In (Obj, N_Indexed_Component,
688 N_Selected_Component)
693 -- Do not check aliased formals or function calls. A
694 -- run-time check may still be needed ???
696 if Is_Entity_Name (Obj)
697 and then Comes_From_Source (Obj)
699 if Is_Formal (Entity (Obj))
700 and then Is_Aliased (Entity (Obj))
704 elsif Object_Access_Level (Obj) >
705 Scope_Depth (Scope (Scope_Id))
708 ("access discriminant in return aggregate would "
709 & "be a dangling reference", Obj);
715 Next_Discriminant (Discr);
718 end Check_Aggregate_Accessibility;
720 -------------------------------------
721 -- Check_Return_Subtype_Indication --
722 -------------------------------------
724 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
725 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
727 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
728 -- Subtype given in the extended return statement (must match R_Type)
730 Subtype_Ind : constant Node_Id :=
731 Object_Definition (Original_Node (Obj_Decl));
733 procedure Error_No_Match (N : Node_Id);
734 -- Output error messages for case where types do not statically
735 -- match. N is the location for the messages.
741 procedure Error_No_Match (N : Node_Id) is
744 ("subtype must statically match function result subtype", N);
746 if not Predicates_Match (R_Stm_Type, R_Type) then
747 Error_Msg_Node_2 := R_Type;
749 ("\predicate of& does not match predicate of&",
754 -- Start of processing for Check_Return_Subtype_Indication
757 -- First, avoid cascaded errors
759 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
763 -- "return access T" case; check that the return statement also has
764 -- "access T", and that the subtypes statically match:
765 -- if this is an access to subprogram the signatures must match.
767 if Is_Anonymous_Access_Type (R_Type) then
768 if Is_Anonymous_Access_Type (R_Stm_Type) then
769 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
771 if Base_Type (Designated_Type (R_Stm_Type)) /=
772 Base_Type (Designated_Type (R_Type))
773 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
775 Error_No_Match (Subtype_Mark (Subtype_Ind));
779 -- For two anonymous access to subprogram types, the types
780 -- themselves must be type conformant.
782 if not Conforming_Types
783 (R_Stm_Type, R_Type, Fully_Conformant)
785 Error_No_Match (Subtype_Ind);
790 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
793 -- If the return object is of an anonymous access type, then report
794 -- an error if the function's result type is not also anonymous.
796 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
797 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
799 ("anonymous access not allowed for function with named access "
800 & "result", Subtype_Ind);
802 -- Subtype indication case: check that the return object's type is
803 -- covered by the result type, and that the subtypes statically match
804 -- when the result subtype is constrained. Also handle record types
805 -- with unknown discriminants for which we have built the underlying
806 -- record view. Coverage is needed to allow specific-type return
807 -- objects when the result type is class-wide (see AI05-32).
809 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
810 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
814 Underlying_Record_View (Base_Type (R_Stm_Type))))
816 -- A null exclusion may be present on the return type, on the
817 -- function specification, on the object declaration or on the
820 if Is_Access_Type (R_Type)
822 (Can_Never_Be_Null (R_Type)
823 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
824 Can_Never_Be_Null (R_Stm_Type)
826 Error_No_Match (Subtype_Ind);
829 -- AI05-103: for elementary types, subtypes must statically match
831 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
832 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
833 Error_No_Match (Subtype_Ind);
837 -- All remaining cases are illegal
839 -- Note: previous versions of this subprogram allowed the return
840 -- value to be the ancestor of the return type if the return type
841 -- was a null extension. This was plainly incorrect.
845 ("wrong type for return_subtype_indication", Subtype_Ind);
847 end Check_Return_Subtype_Indication;
849 ---------------------
850 -- Local Variables --
851 ---------------------
856 -- Start of processing for Analyze_Function_Return
859 Set_Return_Present (Scope_Id);
861 if Nkind (N) = N_Simple_Return_Statement then
862 Expr := Expression (N);
864 -- Guard against a malformed expression. The parser may have tried to
865 -- recover but the node is not analyzable.
867 if Nkind (Expr) = N_Error then
868 Set_Etype (Expr, Any_Type);
869 Expander_Mode_Save_And_Set (False);
873 -- The resolution of a controlled [extension] aggregate associated
874 -- with a return statement creates a temporary which needs to be
875 -- finalized on function exit. Wrap the return statement inside a
876 -- block so that the finalization machinery can detect this case.
877 -- This early expansion is done only when the return statement is
878 -- not part of a handled sequence of statements.
880 if Nkind_In (Expr, N_Aggregate,
881 N_Extension_Aggregate)
882 and then Needs_Finalization (R_Type)
883 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
886 Make_Block_Statement (Loc,
887 Handled_Statement_Sequence =>
888 Make_Handled_Sequence_Of_Statements (Loc,
889 Statements => New_List (Relocate_Node (N)))));
897 -- Ada 2005 (AI-251): If the type of the returned object is
898 -- an access to an interface type then we add an implicit type
899 -- conversion to force the displacement of the "this" pointer to
900 -- reference the secondary dispatch table. We cannot delay the
901 -- generation of this implicit conversion until the expansion
902 -- because in this case the type resolution changes the decoration
903 -- of the expression node to match R_Type; by contrast, if the
904 -- returned object is a class-wide interface type then it is too
905 -- early to generate here the implicit conversion since the return
906 -- statement may be rewritten by the expander into an extended
907 -- return statement whose expansion takes care of adding the
908 -- implicit type conversion to displace the pointer to the object.
911 and then Serious_Errors_Detected = 0
912 and then Is_Access_Type (R_Type)
913 and then Nkind (Expr) /= N_Null
914 and then Is_Interface (Designated_Type (R_Type))
915 and then Is_Progenitor (Designated_Type (R_Type),
916 Designated_Type (Etype (Expr)))
918 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
922 Resolve (Expr, R_Type);
923 Check_Limited_Return (N, Expr, R_Type);
925 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
926 Check_Aggregate_Accessibility (Expr);
930 -- RETURN only allowed in SPARK as the last statement in function
932 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
934 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
935 or else Present (Next (N)))
937 Check_SPARK_05_Restriction
938 ("RETURN should be the last statement in function", N);
942 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
943 Obj_Decl := Last (Return_Object_Declarations (N));
945 -- Analyze parts specific to extended_return_statement:
948 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
949 HSS : constant Node_Id := Handled_Statement_Sequence (N);
952 Expr := Expression (Obj_Decl);
954 -- Note: The check for OK_For_Limited_Init will happen in
955 -- Analyze_Object_Declaration; we treat it as a normal
956 -- object declaration.
958 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
961 Check_Return_Subtype_Indication (Obj_Decl);
963 if Present (HSS) then
966 if Present (Exception_Handlers (HSS)) then
968 -- ???Has_Nested_Block_With_Handler needs to be set.
969 -- Probably by creating an actual N_Block_Statement.
970 -- Probably in Expand.
976 -- Mark the return object as referenced, since the return is an
977 -- implicit reference of the object.
979 Set_Referenced (Defining_Identifier (Obj_Decl));
981 Check_References (Stm_Entity);
983 -- Check RM 6.5 (5.9/3)
986 if Ada_Version < Ada_2012 then
988 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
989 -- Can it really happen (extended return???)
992 ("aliased only allowed for limited return objects "
993 & "in Ada 2012??", N);
995 elsif not Is_Limited_View (R_Type) then
997 ("aliased only allowed for limited return objects", N);
1003 -- Case of Expr present
1007 -- Defend against previous errors
1009 and then Nkind (Expr) /= N_Empty
1010 and then Present (Etype (Expr))
1012 -- Apply constraint check. Note that this is done before the implicit
1013 -- conversion of the expression done for anonymous access types to
1014 -- ensure correct generation of the null-excluding check associated
1015 -- with null-excluding expressions found in return statements.
1017 Apply_Constraint_Check (Expr, R_Type);
1019 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1020 -- type, apply an implicit conversion of the expression to that type
1021 -- to force appropriate static and run-time accessibility checks.
1023 if Ada_Version >= Ada_2005
1024 and then Ekind (R_Type) = E_Anonymous_Access_Type
1026 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1027 Analyze_And_Resolve (Expr, R_Type);
1029 -- If this is a local anonymous access to subprogram, the
1030 -- accessibility check can be applied statically. The return is
1031 -- illegal if the access type of the return expression is declared
1032 -- inside of the subprogram (except if it is the subtype indication
1033 -- of an extended return statement).
1035 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1036 if not Comes_From_Source (Current_Scope)
1037 or else Ekind (Current_Scope) = E_Return_Statement
1042 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1044 Error_Msg_N ("cannot return local access to subprogram", N);
1047 -- The expression cannot be of a formal incomplete type
1049 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1050 and then Is_Generic_Type (Etype (Expr))
1053 ("cannot return expression of a formal incomplete type", N);
1056 -- If the result type is class-wide, then check that the return
1057 -- expression's type is not declared at a deeper level than the
1058 -- function (RM05-6.5(5.6/2)).
1060 if Ada_Version >= Ada_2005
1061 and then Is_Class_Wide_Type (R_Type)
1063 if Type_Access_Level (Etype (Expr)) >
1064 Subprogram_Access_Level (Scope_Id)
1067 ("level of return expression type is deeper than "
1068 & "class-wide function!", Expr);
1072 -- Check incorrect use of dynamically tagged expression
1074 if Is_Tagged_Type (R_Type) then
1075 Check_Dynamically_Tagged_Expression
1081 -- ??? A real run-time accessibility check is needed in cases
1082 -- involving dereferences of access parameters. For now we just
1083 -- check the static cases.
1085 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1086 and then Is_Limited_View (Etype (Scope_Id))
1087 and then Object_Access_Level (Expr) >
1088 Subprogram_Access_Level (Scope_Id)
1090 -- Suppress the message in a generic, where the rewriting
1093 if Inside_A_Generic then
1098 Make_Raise_Program_Error (Loc,
1099 Reason => PE_Accessibility_Check_Failed));
1102 Error_Msg_Warn := SPARK_Mode /= On;
1103 Error_Msg_N ("cannot return a local value by reference<<", N);
1104 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1108 if Known_Null (Expr)
1109 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1110 and then Null_Exclusion_Present (Parent (Scope_Id))
1112 Apply_Compile_Time_Constraint_Error
1114 Msg => "(Ada 2005) null not allowed for "
1115 & "null-excluding return??",
1116 Reason => CE_Null_Not_Allowed);
1119 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1120 -- has no initializing expression.
1122 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1123 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1124 Subprogram_Access_Level (Scope_Id)
1127 ("level of return expression type is deeper than "
1128 & "class-wide function!", Obj_Decl);
1131 end Analyze_Function_Return;
1133 -------------------------------------
1134 -- Analyze_Generic_Subprogram_Body --
1135 -------------------------------------
1137 procedure Analyze_Generic_Subprogram_Body
1141 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1142 Kind : constant Entity_Kind := Ekind (Gen_Id);
1143 Body_Id : Entity_Id;
1148 -- Copy body and disable expansion while analyzing the generic For a
1149 -- stub, do not copy the stub (which would load the proper body), this
1150 -- will be done when the proper body is analyzed.
1152 if Nkind (N) /= N_Subprogram_Body_Stub then
1153 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1156 -- Once the contents of the generic copy and the template are
1157 -- swapped, do the same for their respective aspect specifications.
1159 Exchange_Aspects (N, New_N);
1161 -- Collect all contract-related source pragmas found within the
1162 -- template and attach them to the contract of the subprogram body.
1163 -- This contract is used in the capture of global references within
1166 Create_Generic_Contract (N);
1171 Spec := Specification (N);
1173 -- Within the body of the generic, the subprogram is callable, and
1174 -- behaves like the corresponding non-generic unit.
1176 Body_Id := Defining_Entity (Spec);
1178 if Kind = E_Generic_Procedure
1179 and then Nkind (Spec) /= N_Procedure_Specification
1181 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1184 elsif Kind = E_Generic_Function
1185 and then Nkind (Spec) /= N_Function_Specification
1187 Error_Msg_N ("invalid body for generic function ", Body_Id);
1191 Set_Corresponding_Body (Gen_Decl, Body_Id);
1193 if Has_Completion (Gen_Id)
1194 and then Nkind (Parent (N)) /= N_Subunit
1196 Error_Msg_N ("duplicate generic body", N);
1199 Set_Has_Completion (Gen_Id);
1202 if Nkind (N) = N_Subprogram_Body_Stub then
1203 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1205 Set_Corresponding_Spec (N, Gen_Id);
1208 if Nkind (Parent (N)) = N_Compilation_Unit then
1209 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1212 -- Make generic parameters immediately visible in the body. They are
1213 -- needed to process the formals declarations. Then make the formals
1214 -- visible in a separate step.
1216 Push_Scope (Gen_Id);
1220 First_Ent : Entity_Id;
1223 First_Ent := First_Entity (Gen_Id);
1226 while Present (E) and then not Is_Formal (E) loop
1231 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1233 -- Now generic formals are visible, and the specification can be
1234 -- analyzed, for subsequent conformance check.
1236 Body_Id := Analyze_Subprogram_Specification (Spec);
1238 -- Make formal parameters visible
1242 -- E is the first formal parameter, we loop through the formals
1243 -- installing them so that they will be visible.
1245 Set_First_Entity (Gen_Id, E);
1246 while Present (E) loop
1252 -- Visible generic entity is callable within its own body
1254 Set_Ekind (Gen_Id, Ekind (Body_Id));
1255 Set_Ekind (Body_Id, E_Subprogram_Body);
1256 Set_Convention (Body_Id, Convention (Gen_Id));
1257 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1258 Set_Scope (Body_Id, Scope (Gen_Id));
1260 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1262 if Nkind (N) = N_Subprogram_Body_Stub then
1264 -- No body to analyze, so restore state of generic unit
1266 Set_Ekind (Gen_Id, Kind);
1267 Set_Ekind (Body_Id, Kind);
1269 if Present (First_Ent) then
1270 Set_First_Entity (Gen_Id, First_Ent);
1277 -- If this is a compilation unit, it must be made visible explicitly,
1278 -- because the compilation of the declaration, unlike other library
1279 -- unit declarations, does not. If it is not a unit, the following
1280 -- is redundant but harmless.
1282 Set_Is_Immediately_Visible (Gen_Id);
1283 Reference_Body_Formals (Gen_Id, Body_Id);
1285 if Is_Child_Unit (Gen_Id) then
1286 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1289 Set_Actual_Subtypes (N, Current_Scope);
1291 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1292 Set_SPARK_Pragma_Inherited (Body_Id);
1294 -- Analyze any aspect specifications that appear on the generic
1297 if Has_Aspects (N) then
1298 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
1301 Analyze_Declarations (Declarations (N));
1304 -- Process the contract of the subprogram body after all declarations
1305 -- have been analyzed. This ensures that any contract-related pragmas
1306 -- are available through the N_Contract node of the body.
1308 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1310 Analyze (Handled_Statement_Sequence (N));
1311 Save_Global_References (Original_Node (N));
1313 -- Prior to exiting the scope, include generic formals again (if any
1314 -- are present) in the set of local entities.
1316 if Present (First_Ent) then
1317 Set_First_Entity (Gen_Id, First_Ent);
1320 Check_References (Gen_Id);
1323 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1325 Check_Subprogram_Order (N);
1327 -- Outside of its body, unit is generic again
1329 Set_Ekind (Gen_Id, Kind);
1330 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1333 Style.Check_Identifier (Body_Id, Gen_Id);
1337 end Analyze_Generic_Subprogram_Body;
1339 ----------------------------
1340 -- Analyze_Null_Procedure --
1341 ----------------------------
1343 procedure Analyze_Null_Procedure
1345 Is_Completion : out Boolean)
1347 Loc : constant Source_Ptr := Sloc (N);
1348 Spec : constant Node_Id := Specification (N);
1349 Designator : Entity_Id;
1351 Null_Body : Node_Id := Empty;
1352 Null_Stmt : Node_Id := Null_Statement (Spec);
1356 -- Capture the profile of the null procedure before analysis, for
1357 -- expansion at the freeze point and at each point of call. The body is
1358 -- used if the procedure has preconditions, or if it is a completion. In
1359 -- the first case the body is analyzed at the freeze point, in the other
1360 -- it replaces the null procedure declaration.
1362 -- For a null procedure that comes from source, a NULL statement is
1363 -- provided by the parser, which carries the source location of the
1364 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1365 -- from expansion, create one now.
1367 if No (Null_Stmt) then
1368 Null_Stmt := Make_Null_Statement (Loc);
1372 Make_Subprogram_Body (Loc,
1373 Specification => New_Copy_Tree (Spec),
1374 Declarations => New_List,
1375 Handled_Statement_Sequence =>
1376 Make_Handled_Sequence_Of_Statements (Loc,
1377 Statements => New_List (Null_Stmt)));
1379 -- Create new entities for body and formals
1381 Set_Defining_Unit_Name (Specification (Null_Body),
1382 Make_Defining_Identifier
1383 (Sloc (Defining_Entity (N)),
1384 Chars (Defining_Entity (N))));
1386 Form := First (Parameter_Specifications (Specification (Null_Body)));
1387 while Present (Form) loop
1388 Set_Defining_Identifier (Form,
1389 Make_Defining_Identifier
1390 (Sloc (Defining_Identifier (Form)),
1391 Chars (Defining_Identifier (Form))));
1395 -- Determine whether the null procedure may be a completion of a generic
1396 -- suprogram, in which case we use the new null body as the completion
1397 -- and set minimal semantic information on the original declaration,
1398 -- which is rewritten as a null statement.
1400 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1402 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1403 Insert_Before (N, Null_Body);
1404 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1406 Rewrite (N, Make_Null_Statement (Loc));
1407 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1408 Is_Completion := True;
1412 -- Resolve the types of the formals now, because the freeze point may
1413 -- appear in a different context, e.g. an instantiation.
1415 Form := First (Parameter_Specifications (Specification (Null_Body)));
1416 while Present (Form) loop
1417 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1418 Find_Type (Parameter_Type (Form));
1420 elsif No (Access_To_Subprogram_Definition
1421 (Parameter_Type (Form)))
1423 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1425 -- The case of a null procedure with a formal that is an
1426 -- access-to-subprogram type, and that is used as an actual
1427 -- in an instantiation is left to the enthusiastic reader.
1437 -- If there are previous overloadable entities with the same name, check
1438 -- whether any of them is completed by the null procedure.
1440 if Present (Prev) and then Is_Overloadable (Prev) then
1441 Designator := Analyze_Subprogram_Specification (Spec);
1442 Prev := Find_Corresponding_Spec (N);
1445 if No (Prev) or else not Comes_From_Source (Prev) then
1446 Designator := Analyze_Subprogram_Specification (Spec);
1447 Set_Has_Completion (Designator);
1449 -- Signal to caller that this is a procedure declaration
1451 Is_Completion := False;
1453 -- Null procedures are always inlined, but generic formal subprograms
1454 -- which appear as such in the internal instance of formal packages,
1455 -- need no completion and are not marked Inline.
1458 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1460 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1461 Set_Body_To_Inline (N, Null_Body);
1462 Set_Is_Inlined (Designator);
1466 -- The null procedure is a completion. We unconditionally rewrite
1467 -- this as a null body (even if expansion is not active), because
1468 -- there are various error checks that are applied on this body
1469 -- when it is analyzed (e.g. correct aspect placement).
1471 if Has_Completion (Prev) then
1472 Error_Msg_Sloc := Sloc (Prev);
1473 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1476 Is_Completion := True;
1477 Rewrite (N, Null_Body);
1480 end Analyze_Null_Procedure;
1482 -----------------------------
1483 -- Analyze_Operator_Symbol --
1484 -----------------------------
1486 -- An operator symbol such as "+" or "and" may appear in context where the
1487 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1488 -- is just a string, as in (conjunction = "or"). In these cases the parser
1489 -- generates this node, and the semantics does the disambiguation. Other
1490 -- such case are actuals in an instantiation, the generic unit in an
1491 -- instantiation, and pragma arguments.
1493 procedure Analyze_Operator_Symbol (N : Node_Id) is
1494 Par : constant Node_Id := Parent (N);
1497 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1498 or else Nkind (Par) = N_Function_Instantiation
1499 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1500 or else (Nkind (Par) = N_Pragma_Argument_Association
1501 and then not Is_Pragma_String_Literal (Par))
1502 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1503 or else (Nkind (Par) = N_Attribute_Reference
1504 and then Attribute_Name (Par) /= Name_Value)
1506 Find_Direct_Name (N);
1509 Change_Operator_Symbol_To_String_Literal (N);
1512 end Analyze_Operator_Symbol;
1514 -----------------------------------
1515 -- Analyze_Parameter_Association --
1516 -----------------------------------
1518 procedure Analyze_Parameter_Association (N : Node_Id) is
1520 Analyze (Explicit_Actual_Parameter (N));
1521 end Analyze_Parameter_Association;
1523 ----------------------------
1524 -- Analyze_Procedure_Call --
1525 ----------------------------
1527 -- WARNING: This routine manages Ghost regions. Return statements must be
1528 -- replaced by gotos which jump to the end of the routine and restore the
1531 procedure Analyze_Procedure_Call (N : Node_Id) is
1532 procedure Analyze_Call_And_Resolve;
1533 -- Do Analyze and Resolve calls for procedure call. At the end, check
1534 -- for illegal order dependence.
1535 -- ??? where is the check for illegal order dependencies?
1537 ------------------------------
1538 -- Analyze_Call_And_Resolve --
1539 ------------------------------
1541 procedure Analyze_Call_And_Resolve is
1543 if Nkind (N) = N_Procedure_Call_Statement then
1545 Resolve (N, Standard_Void_Type);
1549 end Analyze_Call_And_Resolve;
1553 Actuals : constant List_Id := Parameter_Associations (N);
1554 Loc : constant Source_Ptr := Sloc (N);
1555 P : constant Node_Id := Name (N);
1557 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1558 -- Save the Ghost mode to restore on exit
1563 -- Start of processing for Analyze_Procedure_Call
1566 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1567 -- a procedure call or an entry call. The prefix may denote an access
1568 -- to subprogram type, in which case an implicit dereference applies.
1569 -- If the prefix is an indexed component (without implicit dereference)
1570 -- then the construct denotes a call to a member of an entire family.
1571 -- If the prefix is a simple name, it may still denote a call to a
1572 -- parameterless member of an entry family. Resolution of these various
1573 -- interpretations is delicate.
1575 -- Do not analyze machine code statements to avoid rejecting them in
1578 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1579 Set_Etype (P, Standard_Void_Type);
1584 -- If this is a call of the form Obj.Op, the call may have been analyzed
1585 -- and possibly rewritten into a block, in which case we are done.
1587 if Analyzed (N) then
1591 -- If there is an error analyzing the name (which may have been
1592 -- rewritten if the original call was in prefix notation) then error
1593 -- has been emitted already, mark node and return.
1595 if Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1596 Set_Etype (N, Any_Type);
1600 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1601 -- Set the mode now to ensure that any nodes generated during analysis
1602 -- and expansion are properly marked as Ghost.
1604 Mark_And_Set_Ghost_Procedure_Call (N);
1606 -- Otherwise analyze the parameters
1608 if Present (Actuals) then
1609 Actual := First (Actuals);
1611 while Present (Actual) loop
1613 Check_Parameterless_Call (Actual);
1618 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1620 if Nkind (P) = N_Attribute_Reference
1621 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1623 Name_Elab_Subp_Body)
1625 if Present (Actuals) then
1627 ("no parameters allowed for this call", First (Actuals));
1631 Set_Etype (N, Standard_Void_Type);
1634 elsif Is_Entity_Name (P)
1635 and then Is_Record_Type (Etype (Entity (P)))
1636 and then Remote_AST_I_Dereference (P)
1640 elsif Is_Entity_Name (P)
1641 and then Ekind (Entity (P)) /= E_Entry_Family
1643 if Is_Access_Type (Etype (P))
1644 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1645 and then No (Actuals)
1646 and then Comes_From_Source (N)
1648 Error_Msg_N ("missing explicit dereference in call", N);
1651 Analyze_Call_And_Resolve;
1653 -- If the prefix is the simple name of an entry family, this is a
1654 -- parameterless call from within the task body itself.
1656 elsif Is_Entity_Name (P)
1657 and then Nkind (P) = N_Identifier
1658 and then Ekind (Entity (P)) = E_Entry_Family
1659 and then Present (Actuals)
1660 and then No (Next (First (Actuals)))
1662 -- Can be call to parameterless entry family. What appears to be the
1663 -- sole argument is in fact the entry index. Rewrite prefix of node
1664 -- accordingly. Source representation is unchanged by this
1668 Make_Indexed_Component (Loc,
1670 Make_Selected_Component (Loc,
1671 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1672 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1673 Expressions => Actuals);
1674 Set_Name (N, New_N);
1675 Set_Etype (New_N, Standard_Void_Type);
1676 Set_Parameter_Associations (N, No_List);
1677 Analyze_Call_And_Resolve;
1679 elsif Nkind (P) = N_Explicit_Dereference then
1680 if Ekind (Etype (P)) = E_Subprogram_Type then
1681 Analyze_Call_And_Resolve;
1683 Error_Msg_N ("expect access to procedure in call", P);
1686 -- The name can be a selected component or an indexed component that
1687 -- yields an access to subprogram. Such a prefix is legal if the call
1688 -- has parameter associations.
1690 elsif Is_Access_Type (Etype (P))
1691 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1693 if Present (Actuals) then
1694 Analyze_Call_And_Resolve;
1696 Error_Msg_N ("missing explicit dereference in call ", N);
1699 -- If not an access to subprogram, then the prefix must resolve to the
1700 -- name of an entry, entry family, or protected operation.
1702 -- For the case of a simple entry call, P is a selected component where
1703 -- the prefix is the task and the selector name is the entry. A call to
1704 -- a protected procedure will have the same syntax. If the protected
1705 -- object contains overloaded operations, the entity may appear as a
1706 -- function, the context will select the operation whose type is Void.
1708 elsif Nkind (P) = N_Selected_Component
1709 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1713 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1714 -- in prefix notation may still be missing its controlling argument,
1715 -- so perform the transformation now.
1717 if SPARK_Mode = On and then In_Inlined_Body then
1719 Subp : constant Entity_Id := Entity (Selector_Name (P));
1720 Typ : constant Entity_Id := Etype (Prefix (P));
1723 if Is_Tagged_Type (Typ)
1724 and then Present (First_Formal (Subp))
1725 and then Etype (First_Formal (Subp)) = Typ
1726 and then Try_Object_Operation (P)
1731 Analyze_Call_And_Resolve;
1736 Analyze_Call_And_Resolve;
1739 elsif Nkind (P) = N_Selected_Component
1740 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1741 and then Present (Actuals)
1742 and then No (Next (First (Actuals)))
1744 -- Can be call to parameterless entry family. What appears to be the
1745 -- sole argument is in fact the entry index. Rewrite prefix of node
1746 -- accordingly. Source representation is unchanged by this
1750 Make_Indexed_Component (Loc,
1751 Prefix => New_Copy (P),
1752 Expressions => Actuals);
1753 Set_Name (N, New_N);
1754 Set_Etype (New_N, Standard_Void_Type);
1755 Set_Parameter_Associations (N, No_List);
1756 Analyze_Call_And_Resolve;
1758 -- For the case of a reference to an element of an entry family, P is
1759 -- an indexed component whose prefix is a selected component (task and
1760 -- entry family), and whose index is the entry family index.
1762 elsif Nkind (P) = N_Indexed_Component
1763 and then Nkind (Prefix (P)) = N_Selected_Component
1764 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1766 Analyze_Call_And_Resolve;
1768 -- If the prefix is the name of an entry family, it is a call from
1769 -- within the task body itself.
1771 elsif Nkind (P) = N_Indexed_Component
1772 and then Nkind (Prefix (P)) = N_Identifier
1773 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1776 Make_Selected_Component (Loc,
1777 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1778 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1779 Rewrite (Prefix (P), New_N);
1781 Analyze_Call_And_Resolve;
1783 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1784 -- procedure name, so the construct can only be a qualified expression.
1786 elsif Nkind (P) = N_Qualified_Expression
1787 and then Ada_Version >= Ada_2012
1789 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1792 -- Anything else is an error
1795 Error_Msg_N ("invalid procedure or entry call", N);
1799 Restore_Ghost_Mode (Saved_GM);
1800 end Analyze_Procedure_Call;
1802 ------------------------------
1803 -- Analyze_Return_Statement --
1804 ------------------------------
1806 procedure Analyze_Return_Statement (N : Node_Id) is
1807 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
1808 N_Simple_Return_Statement));
1810 Returns_Object : constant Boolean :=
1811 Nkind (N) = N_Extended_Return_Statement
1813 (Nkind (N) = N_Simple_Return_Statement
1814 and then Present (Expression (N)));
1815 -- True if we're returning something; that is, "return <expression>;"
1816 -- or "return Result : T [:= ...]". False for "return;". Used for error
1817 -- checking: If Returns_Object is True, N should apply to a function
1818 -- body; otherwise N should apply to a procedure body, entry body,
1819 -- accept statement, or extended return statement.
1821 function Find_What_It_Applies_To return Entity_Id;
1822 -- Find the entity representing the innermost enclosing body, accept
1823 -- statement, or extended return statement. If the result is a callable
1824 -- construct or extended return statement, then this will be the value
1825 -- of the Return_Applies_To attribute. Otherwise, the program is
1826 -- illegal. See RM-6.5(4/2).
1828 -----------------------------
1829 -- Find_What_It_Applies_To --
1830 -----------------------------
1832 function Find_What_It_Applies_To return Entity_Id is
1833 Result : Entity_Id := Empty;
1836 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1837 -- and postconditions.
1839 for J in reverse 0 .. Scope_Stack.Last loop
1840 Result := Scope_Stack.Table (J).Entity;
1841 exit when not Ekind_In (Result, E_Block, E_Loop)
1842 and then Chars (Result) /= Name_uPostconditions;
1845 pragma Assert (Present (Result));
1847 end Find_What_It_Applies_To;
1849 -- Local declarations
1851 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1852 Kind : constant Entity_Kind := Ekind (Scope_Id);
1853 Loc : constant Source_Ptr := Sloc (N);
1854 Stm_Entity : constant Entity_Id :=
1856 (E_Return_Statement, Current_Scope, Loc, 'R');
1858 -- Start of processing for Analyze_Return_Statement
1861 Set_Return_Statement_Entity (N, Stm_Entity);
1863 Set_Etype (Stm_Entity, Standard_Void_Type);
1864 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1866 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1867 -- (4/2): an inner return statement will apply to this extended return.
1869 if Nkind (N) = N_Extended_Return_Statement then
1870 Push_Scope (Stm_Entity);
1873 -- Check that pragma No_Return is obeyed. Don't complain about the
1874 -- implicitly-generated return that is placed at the end.
1876 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1877 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1880 -- Warn on any unassigned OUT parameters if in procedure
1882 if Ekind (Scope_Id) = E_Procedure then
1883 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1886 -- Check that functions return objects, and other things do not
1888 if Kind = E_Function or else Kind = E_Generic_Function then
1889 if not Returns_Object then
1890 Error_Msg_N ("missing expression in return from function", N);
1893 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1894 if Returns_Object then
1895 Error_Msg_N ("procedure cannot return value (use function)", N);
1898 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1899 if Returns_Object then
1900 if Is_Protected_Type (Scope (Scope_Id)) then
1901 Error_Msg_N ("entry body cannot return value", N);
1903 Error_Msg_N ("accept statement cannot return value", N);
1907 elsif Kind = E_Return_Statement then
1909 -- We are nested within another return statement, which must be an
1910 -- extended_return_statement.
1912 if Returns_Object then
1913 if Nkind (N) = N_Extended_Return_Statement then
1915 ("extended return statement cannot be nested (use `RETURN;`)",
1918 -- Case of a simple return statement with a value inside extended
1919 -- return statement.
1923 ("return nested in extended return statement cannot return "
1924 & "value (use `RETURN;`)", N);
1929 Error_Msg_N ("illegal context for return statement", N);
1932 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1933 Analyze_Function_Return (N);
1935 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1936 Set_Return_Present (Scope_Id);
1939 if Nkind (N) = N_Extended_Return_Statement then
1943 Kill_Current_Values (Last_Assignment_Only => True);
1944 Check_Unreachable_Code (N);
1946 Analyze_Dimension (N);
1947 end Analyze_Return_Statement;
1949 -------------------------------------
1950 -- Analyze_Simple_Return_Statement --
1951 -------------------------------------
1953 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1955 if Present (Expression (N)) then
1956 Mark_Coextensions (N, Expression (N));
1959 Analyze_Return_Statement (N);
1960 end Analyze_Simple_Return_Statement;
1962 -------------------------
1963 -- Analyze_Return_Type --
1964 -------------------------
1966 procedure Analyze_Return_Type (N : Node_Id) is
1967 Designator : constant Entity_Id := Defining_Entity (N);
1968 Typ : Entity_Id := Empty;
1971 -- Normal case where result definition does not indicate an error
1973 if Result_Definition (N) /= Error then
1974 if Nkind (Result_Definition (N)) = N_Access_Definition then
1975 Check_SPARK_05_Restriction
1976 ("access result is not allowed", Result_Definition (N));
1978 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1981 AD : constant Node_Id :=
1982 Access_To_Subprogram_Definition (Result_Definition (N));
1984 if Present (AD) and then Protected_Present (AD) then
1985 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1987 Typ := Access_Definition (N, Result_Definition (N));
1991 Set_Parent (Typ, Result_Definition (N));
1992 Set_Is_Local_Anonymous_Access (Typ);
1993 Set_Etype (Designator, Typ);
1995 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1997 Null_Exclusion_Static_Checks (N);
1999 -- Subtype_Mark case
2002 Find_Type (Result_Definition (N));
2003 Typ := Entity (Result_Definition (N));
2004 Set_Etype (Designator, Typ);
2006 -- Unconstrained array as result is not allowed in SPARK
2008 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2009 Check_SPARK_05_Restriction
2010 ("returning an unconstrained array is not allowed",
2011 Result_Definition (N));
2014 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2016 Null_Exclusion_Static_Checks (N);
2018 -- If a null exclusion is imposed on the result type, then create
2019 -- a null-excluding itype (an access subtype) and use it as the
2020 -- function's Etype. Note that the null exclusion checks are done
2021 -- right before this, because they don't get applied to types that
2022 -- do not come from source.
2024 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2025 Set_Etype (Designator,
2026 Create_Null_Excluding_Itype
2029 Scope_Id => Scope (Current_Scope)));
2031 -- The new subtype must be elaborated before use because
2032 -- it is visible outside of the function. However its base
2033 -- type may not be frozen yet, so the reference that will
2034 -- force elaboration must be attached to the freezing of
2037 -- If the return specification appears on a proper body,
2038 -- the subtype will have been created already on the spec.
2040 if Is_Frozen (Typ) then
2041 if Nkind (Parent (N)) = N_Subprogram_Body
2042 and then Nkind (Parent (Parent (N))) = N_Subunit
2046 Build_Itype_Reference (Etype (Designator), Parent (N));
2050 Ensure_Freeze_Node (Typ);
2053 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2055 Set_Itype (IR, Etype (Designator));
2056 Append_Freeze_Actions (Typ, New_List (IR));
2061 Set_Etype (Designator, Typ);
2064 if Ekind (Typ) = E_Incomplete_Type
2065 or else (Is_Class_Wide_Type (Typ)
2066 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2068 -- AI05-0151: Tagged incomplete types are allowed in all formal
2069 -- parts. Untagged incomplete types are not allowed in bodies.
2070 -- As a consequence, limited views cannot appear in a basic
2071 -- declaration that is itself within a body, because there is
2072 -- no point at which the non-limited view will become visible.
2074 if Ada_Version >= Ada_2012 then
2075 if From_Limited_With (Typ) and then In_Package_Body then
2077 ("invalid use of incomplete type&",
2078 Result_Definition (N), Typ);
2080 -- The return type of a subprogram body cannot be of a
2081 -- formal incomplete type.
2083 elsif Is_Generic_Type (Typ)
2084 and then Nkind (Parent (N)) = N_Subprogram_Body
2087 ("return type cannot be a formal incomplete type",
2088 Result_Definition (N));
2090 elsif Is_Class_Wide_Type (Typ)
2091 and then Is_Generic_Type (Root_Type (Typ))
2092 and then Nkind (Parent (N)) = N_Subprogram_Body
2095 ("return type cannot be a formal incomplete type",
2096 Result_Definition (N));
2098 elsif Is_Tagged_Type (Typ) then
2101 -- Use is legal in a thunk generated for an operation
2102 -- inherited from a progenitor.
2104 elsif Is_Thunk (Designator)
2105 and then Present (Non_Limited_View (Typ))
2109 elsif Nkind (Parent (N)) = N_Subprogram_Body
2110 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2114 ("invalid use of untagged incomplete type&",
2118 -- The type must be completed in the current package. This
2119 -- is checked at the end of the package declaration when
2120 -- Taft-amendment types are identified. If the return type
2121 -- is class-wide, there is no required check, the type can
2122 -- be a bona fide TAT.
2124 if Ekind (Scope (Current_Scope)) = E_Package
2125 and then In_Private_Part (Scope (Current_Scope))
2126 and then not Is_Class_Wide_Type (Typ)
2128 Append_Elmt (Designator, Private_Dependents (Typ));
2133 ("invalid use of incomplete type&", Designator, Typ);
2138 -- Case where result definition does indicate an error
2141 Set_Etype (Designator, Any_Type);
2143 end Analyze_Return_Type;
2145 -----------------------------
2146 -- Analyze_Subprogram_Body --
2147 -----------------------------
2149 procedure Analyze_Subprogram_Body (N : Node_Id) is
2150 Loc : constant Source_Ptr := Sloc (N);
2151 Body_Spec : constant Node_Id := Specification (N);
2152 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2155 if Debug_Flag_C then
2156 Write_Str ("==> subprogram body ");
2157 Write_Name (Chars (Body_Id));
2158 Write_Str (" from ");
2159 Write_Location (Loc);
2164 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2166 -- The real work is split out into the helper, so it can do "return;"
2167 -- without skipping the debug output:
2169 Analyze_Subprogram_Body_Helper (N);
2171 if Debug_Flag_C then
2173 Write_Str ("<== subprogram body ");
2174 Write_Name (Chars (Body_Id));
2175 Write_Str (" from ");
2176 Write_Location (Loc);
2179 end Analyze_Subprogram_Body;
2181 ------------------------------------
2182 -- Analyze_Subprogram_Body_Helper --
2183 ------------------------------------
2185 -- This procedure is called for regular subprogram bodies, generic bodies,
2186 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2187 -- specification matters, and is used to create a proper declaration for
2188 -- the subprogram, or to perform conformance checks.
2190 -- WARNING: This routine manages Ghost regions. Return statements must be
2191 -- replaced by gotos which jump to the end of the routine and restore the
2194 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2195 Body_Spec : Node_Id := Specification (N);
2196 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2197 Loc : constant Source_Ptr := Sloc (N);
2198 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2200 Conformant : Boolean;
2201 Desig_View : Entity_Id := Empty;
2202 Exch_Views : Elist_Id := No_Elist;
2204 Prot_Typ : Entity_Id := Empty;
2205 Spec_Decl : Node_Id := Empty;
2206 Spec_Id : Entity_Id;
2208 Last_Real_Spec_Entity : Entity_Id := Empty;
2209 -- When we analyze a separate spec, the entity chain ends up containing
2210 -- the formals, as well as any itypes generated during analysis of the
2211 -- default expressions for parameters, or the arguments of associated
2212 -- precondition/postcondition pragmas (which are analyzed in the context
2213 -- of the spec since they have visibility on formals).
2215 -- These entities belong with the spec and not the body. However we do
2216 -- the analysis of the body in the context of the spec (again to obtain
2217 -- visibility to the formals), and all the entities generated during
2218 -- this analysis end up also chained to the entity chain of the spec.
2219 -- But they really belong to the body, and there is circuitry to move
2220 -- them from the spec to the body.
2222 -- However, when we do this move, we don't want to move the real spec
2223 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2224 -- variable points to the last real spec entity, so we only move those
2225 -- chained beyond that point. It is initialized to Empty to deal with
2226 -- the case where there is no separate spec.
2228 function Body_Has_Contract return Boolean;
2229 -- Check whether unanalyzed body has an aspect or pragma that may
2230 -- generate a SPARK contract.
2232 function Body_Has_SPARK_Mode_On return Boolean;
2233 -- Check whether SPARK_Mode On applies to the subprogram body, either
2234 -- because it is specified directly on the body, or because it is
2235 -- inherited from the enclosing subprogram or package.
2237 procedure Build_Subprogram_Declaration;
2238 -- Create a matching subprogram declaration for subprogram body N
2240 procedure Check_Anonymous_Return;
2241 -- Ada 2005: if a function returns an access type that denotes a task,
2242 -- or a type that contains tasks, we must create a master entity for
2243 -- the anonymous type, which typically will be used in an allocator
2244 -- in the body of the function.
2246 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2247 -- Look ahead to recognize a pragma that may appear after the body.
2248 -- If there is a previous spec, check that it appears in the same
2249 -- declarative part. If the pragma is Inline_Always, perform inlining
2250 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2251 -- If the body acts as a spec, and inlining is required, we create a
2252 -- subprogram declaration for it, in order to attach the body to inline.
2253 -- If pragma does not appear after the body, check whether there is
2254 -- an inline pragma before any local declarations.
2256 procedure Check_Missing_Return;
2257 -- Checks for a function with a no return statements, and also performs
2258 -- the warning checks implemented by Check_Returns. In formal mode, also
2259 -- verify that a function ends with a RETURN and that a procedure does
2260 -- not contain any RETURN.
2262 function Disambiguate_Spec return Entity_Id;
2263 -- When a primitive is declared between the private view and the full
2264 -- view of a concurrent type which implements an interface, a special
2265 -- mechanism is used to find the corresponding spec of the primitive
2268 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2269 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2270 -- incomplete types coming from a limited context and replace their
2271 -- limited views with the non-limited ones. Return the list of changes
2272 -- to be used to undo the transformation.
2274 procedure Freeze_Expr_Types (Spec_Id : Entity_Id);
2275 -- AI12-0103: N is the body associated with an expression function that
2276 -- is a completion, and Spec_Id is its defining entity. Freeze before N
2277 -- all the types referenced by the expression of the function.
2279 function Is_Private_Concurrent_Primitive
2280 (Subp_Id : Entity_Id) return Boolean;
2281 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2282 -- type that implements an interface and has a private view.
2284 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2285 -- Undo the transformation done by Exchange_Limited_Views.
2287 procedure Set_Trivial_Subprogram (N : Node_Id);
2288 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2289 -- subprogram whose body is being analyzed. N is the statement node
2290 -- causing the flag to be set, if the following statement is a return
2291 -- of an entity, we mark the entity as set in source to suppress any
2292 -- warning on the stylized use of function stubs with a dummy return.
2294 procedure Verify_Overriding_Indicator;
2295 -- If there was a previous spec, the entity has been entered in the
2296 -- current scope previously. If the body itself carries an overriding
2297 -- indicator, check that it is consistent with the known status of the
2300 -----------------------
2301 -- Body_Has_Contract --
2302 -----------------------
2304 function Body_Has_Contract return Boolean is
2305 Decls : constant List_Id := Declarations (N);
2309 -- Check for aspects that may generate a contract
2311 if Present (Aspect_Specifications (N)) then
2312 Item := First (Aspect_Specifications (N));
2313 while Present (Item) loop
2314 if Is_Subprogram_Contract_Annotation (Item) then
2322 -- Check for pragmas that may generate a contract
2324 if Present (Decls) then
2325 Item := First (Decls);
2326 while Present (Item) loop
2327 if Nkind (Item) = N_Pragma
2328 and then Is_Subprogram_Contract_Annotation (Item)
2338 end Body_Has_Contract;
2340 ----------------------------
2341 -- Body_Has_SPARK_Mode_On --
2342 ----------------------------
2344 function Body_Has_SPARK_Mode_On return Boolean is
2345 Decls : constant List_Id := Declarations (N);
2349 -- Check for SPARK_Mode aspect
2351 if Present (Aspect_Specifications (N)) then
2352 Item := First (Aspect_Specifications (N));
2353 while Present (Item) loop
2354 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2355 return Get_SPARK_Mode_From_Annotation (Item) = On;
2362 -- Check for SPARK_Mode pragma
2364 if Present (Decls) then
2365 Item := First (Decls);
2366 while Present (Item) loop
2368 -- Pragmas that apply to a subprogram body are usually grouped
2369 -- together. Look for a potential pragma SPARK_Mode among them.
2371 if Nkind (Item) = N_Pragma then
2372 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2373 return Get_SPARK_Mode_From_Annotation (Item) = On;
2376 -- Otherwise the first non-pragma declarative item terminates
2377 -- the region where pragma SPARK_Mode may appear.
2387 -- Otherwise, the applicable SPARK_Mode is inherited from the
2388 -- enclosing subprogram or package.
2390 return SPARK_Mode = On;
2391 end Body_Has_SPARK_Mode_On;
2393 ----------------------------------
2394 -- Build_Subprogram_Declaration --
2395 ----------------------------------
2397 procedure Build_Subprogram_Declaration is
2398 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2399 -- Relocate certain categorization pragmas from the declarative list
2400 -- of subprogram body From and insert them after node To. The pragmas
2403 -- Volatile_Function
2404 -- Also copy pragma SPARK_Mode if present in the declarative list
2405 -- of subprogram body From and insert it after node To. This pragma
2406 -- should not be moved, as it applies to the body too.
2412 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2414 Next_Decl : Node_Id;
2417 pragma Assert (Nkind (From) = N_Subprogram_Body);
2419 -- The destination node must be part of a list, as the pragmas are
2420 -- inserted after it.
2422 pragma Assert (Is_List_Member (To));
2424 -- Inspect the declarations of the subprogram body looking for
2425 -- specific pragmas.
2427 Decl := First (Declarations (N));
2428 while Present (Decl) loop
2429 Next_Decl := Next (Decl);
2431 if Nkind (Decl) = N_Pragma then
2432 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2433 Insert_After (To, New_Copy_Tree (Decl));
2435 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2437 Name_Volatile_Function)
2440 Insert_After (To, Decl);
2451 Subp_Decl : Node_Id;
2453 -- Start of processing for Build_Subprogram_Declaration
2456 -- Create a matching subprogram spec using the profile of the body.
2457 -- The structure of the tree is identical, but has new entities for
2458 -- the defining unit name and formal parameters.
2461 Make_Subprogram_Declaration (Loc,
2462 Specification => Copy_Subprogram_Spec (Body_Spec));
2463 Set_Comes_From_Source (Subp_Decl, True);
2465 -- Relocate the aspects and relevant pragmas from the subprogram body
2466 -- to the generated spec because it acts as the initial declaration.
2468 Insert_Before (N, Subp_Decl);
2469 Move_Aspects (N, To => Subp_Decl);
2470 Move_Pragmas (N, To => Subp_Decl);
2472 -- Ensure that the generated corresponding spec and original body
2473 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2474 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2475 -- correctly set for local subprograms.
2477 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2479 Analyze (Subp_Decl);
2481 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2482 -- the body since the expander may generate calls using that entity.
2483 -- Required to ensure that Expand_Call rewrites calls to this
2484 -- function by calls to the built procedure.
2486 if Modify_Tree_For_C
2487 and then Nkind (Body_Spec) = N_Function_Specification
2489 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2491 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2492 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2493 Corresponding_Procedure
2494 (Defining_Entity (Specification (Subp_Decl))));
2497 -- Analyze any relocated source pragmas or pragmas created for aspect
2500 Decl := Next (Subp_Decl);
2501 while Present (Decl) loop
2503 -- Stop the search for pragmas once the body has been reached as
2504 -- this terminates the region where pragmas may appear.
2509 elsif Nkind (Decl) = N_Pragma then
2516 Spec_Id := Defining_Entity (Subp_Decl);
2517 Set_Corresponding_Spec (N, Spec_Id);
2519 -- Mark the generated spec as a source construct to ensure that all
2520 -- calls to it are properly registered in ALI files for GNATprove.
2522 Set_Comes_From_Source (Spec_Id, True);
2524 -- Ensure that the specs of the subprogram declaration and its body
2525 -- are identical, otherwise they will appear non-conformant due to
2526 -- rewritings in the default values of formal parameters.
2528 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2529 Set_Specification (N, Body_Spec);
2530 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2531 end Build_Subprogram_Declaration;
2533 ----------------------------
2534 -- Check_Anonymous_Return --
2535 ----------------------------
2537 procedure Check_Anonymous_Return is
2543 if Present (Spec_Id) then
2549 if Ekind (Scop) = E_Function
2550 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2551 and then not Is_Thunk (Scop)
2553 -- Skip internally built functions which handle the case of
2554 -- a null access (see Expand_Interface_Conversion)
2556 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2557 and then not Comes_From_Source (Parent (Scop)))
2559 and then (Has_Task (Designated_Type (Etype (Scop)))
2561 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2563 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2564 and then Expander_Active
2566 -- Avoid cases with no tasking support
2568 and then RTE_Available (RE_Current_Master)
2569 and then not Restriction_Active (No_Task_Hierarchy)
2572 Make_Object_Declaration (Loc,
2573 Defining_Identifier =>
2574 Make_Defining_Identifier (Loc, Name_uMaster),
2575 Constant_Present => True,
2576 Object_Definition =>
2577 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2579 Make_Explicit_Dereference (Loc,
2580 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2582 if Present (Declarations (N)) then
2583 Prepend (Decl, Declarations (N));
2585 Set_Declarations (N, New_List (Decl));
2588 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2589 Set_Has_Master_Entity (Scop);
2591 -- Now mark the containing scope as a task master
2594 while Nkind (Par) /= N_Compilation_Unit loop
2595 Par := Parent (Par);
2596 pragma Assert (Present (Par));
2598 -- If we fall off the top, we are at the outer level, and
2599 -- the environment task is our effective master, so nothing
2603 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2605 Set_Is_Task_Master (Par, True);
2610 end Check_Anonymous_Return;
2612 -------------------------
2613 -- Check_Inline_Pragma --
2614 -------------------------
2616 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2620 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2621 -- True when N is a pragma Inline or Inline_Always that applies
2622 -- to this subprogram.
2624 -----------------------
2625 -- Is_Inline_Pragma --
2626 -----------------------
2628 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2630 if Nkind (N) = N_Pragma
2632 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2633 or else (Pragma_Name_Unmapped (N) = Name_Inline
2635 (Front_End_Inlining or else Optimization_Level > 0)))
2636 and then Present (Pragma_Argument_Associations (N))
2639 Pragma_Arg : Node_Id :=
2640 Expression (First (Pragma_Argument_Associations (N)));
2642 if Nkind (Pragma_Arg) = N_Selected_Component then
2643 Pragma_Arg := Selector_Name (Pragma_Arg);
2646 return Chars (Pragma_Arg) = Chars (Body_Id);
2652 end Is_Inline_Pragma;
2654 -- Start of processing for Check_Inline_Pragma
2657 if not Expander_Active then
2661 if Is_List_Member (N)
2662 and then Present (Next (N))
2663 and then Is_Inline_Pragma (Next (N))
2667 elsif Nkind (N) /= N_Subprogram_Body_Stub
2668 and then Present (Declarations (N))
2669 and then Is_Inline_Pragma (First (Declarations (N)))
2671 Prag := First (Declarations (N));
2677 if Present (Prag) then
2678 if Present (Spec_Id) then
2679 if Is_List_Member (N)
2680 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2681 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2687 -- Create a subprogram declaration, to make treatment uniform.
2688 -- Make the sloc of the subprogram name that of the entity in
2689 -- the body, so that style checks find identical strings.
2692 Subp : constant Entity_Id :=
2693 Make_Defining_Identifier
2694 (Sloc (Body_Id), Chars (Body_Id));
2695 Decl : constant Node_Id :=
2696 Make_Subprogram_Declaration (Loc,
2698 New_Copy_Tree (Specification (N)));
2701 Set_Defining_Unit_Name (Specification (Decl), Subp);
2703 -- To ensure proper coverage when body is inlined, indicate
2704 -- whether the subprogram comes from source.
2706 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2708 if Present (First_Formal (Body_Id)) then
2709 Plist := Copy_Parameter_List (Body_Id);
2710 Set_Parameter_Specifications
2711 (Specification (Decl), Plist);
2714 -- Move aspects to the new spec
2716 if Has_Aspects (N) then
2717 Move_Aspects (N, To => Decl);
2720 Insert_Before (N, Decl);
2723 Set_Has_Pragma_Inline (Subp);
2725 if Pragma_Name (Prag) = Name_Inline_Always then
2726 Set_Is_Inlined (Subp);
2727 Set_Has_Pragma_Inline_Always (Subp);
2730 -- Prior to copying the subprogram body to create a template
2731 -- for it for subsequent inlining, remove the pragma from
2732 -- the current body so that the copy that will produce the
2733 -- new body will start from a completely unanalyzed tree.
2735 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2736 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2743 end Check_Inline_Pragma;
2745 --------------------------
2746 -- Check_Missing_Return --
2747 --------------------------
2749 procedure Check_Missing_Return is
2751 Missing_Ret : Boolean;
2754 if Nkind (Body_Spec) = N_Function_Specification then
2755 if Present (Spec_Id) then
2761 if Return_Present (Id) then
2762 Check_Returns (HSS, 'F', Missing_Ret);
2765 Set_Has_Missing_Return (Id);
2768 -- Within a premature instantiation of a package with no body, we
2769 -- build completions of the functions therein, with a Raise
2770 -- statement. No point in complaining about a missing return in
2773 elsif Ekind (Id) = E_Function
2774 and then In_Instance
2775 and then Present (Statements (HSS))
2776 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2780 elsif Is_Generic_Subprogram (Id)
2781 or else not Is_Machine_Code_Subprogram (Id)
2783 Error_Msg_N ("missing RETURN statement in function body", N);
2786 -- If procedure with No_Return, check returns
2788 elsif Nkind (Body_Spec) = N_Procedure_Specification
2789 and then Present (Spec_Id)
2790 and then No_Return (Spec_Id)
2792 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2795 -- Special checks in SPARK mode
2797 if Nkind (Body_Spec) = N_Function_Specification then
2799 -- In SPARK mode, last statement of a function should be a return
2802 Stat : constant Node_Id := Last_Source_Statement (HSS);
2805 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2806 N_Extended_Return_Statement)
2808 Check_SPARK_05_Restriction
2809 ("last statement in function should be RETURN", Stat);
2813 -- In SPARK mode, verify that a procedure has no return
2815 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2816 if Present (Spec_Id) then
2822 -- Would be nice to point to return statement here, can we
2823 -- borrow the Check_Returns procedure here ???
2825 if Return_Present (Id) then
2826 Check_SPARK_05_Restriction
2827 ("procedure should not have RETURN", N);
2830 end Check_Missing_Return;
2832 -----------------------
2833 -- Disambiguate_Spec --
2834 -----------------------
2836 function Disambiguate_Spec return Entity_Id is
2837 Priv_Spec : Entity_Id;
2840 procedure Replace_Types (To_Corresponding : Boolean);
2841 -- Depending on the flag, replace the type of formal parameters of
2842 -- Body_Id if it is a concurrent type implementing interfaces with
2843 -- the corresponding record type or the other way around.
2845 procedure Replace_Types (To_Corresponding : Boolean) is
2847 Formal_Typ : Entity_Id;
2850 Formal := First_Formal (Body_Id);
2851 while Present (Formal) loop
2852 Formal_Typ := Etype (Formal);
2854 if Is_Class_Wide_Type (Formal_Typ) then
2855 Formal_Typ := Root_Type (Formal_Typ);
2858 -- From concurrent type to corresponding record
2860 if To_Corresponding then
2861 if Is_Concurrent_Type (Formal_Typ)
2862 and then Present (Corresponding_Record_Type (Formal_Typ))
2865 (Corresponding_Record_Type (Formal_Typ)))
2868 Corresponding_Record_Type (Formal_Typ));
2871 -- From corresponding record to concurrent type
2874 if Is_Concurrent_Record_Type (Formal_Typ)
2875 and then Present (Interfaces (Formal_Typ))
2878 Corresponding_Concurrent_Type (Formal_Typ));
2882 Next_Formal (Formal);
2886 -- Start of processing for Disambiguate_Spec
2889 -- Try to retrieve the specification of the body as is. All error
2890 -- messages are suppressed because the body may not have a spec in
2891 -- its current state.
2893 Spec_N := Find_Corresponding_Spec (N, False);
2895 -- It is possible that this is the body of a primitive declared
2896 -- between a private and a full view of a concurrent type. The
2897 -- controlling parameter of the spec carries the concurrent type,
2898 -- not the corresponding record type as transformed by Analyze_
2899 -- Subprogram_Specification. In such cases, we undo the change
2900 -- made by the analysis of the specification and try to find the
2903 -- Note that wrappers already have their corresponding specs and
2904 -- bodies set during their creation, so if the candidate spec is
2905 -- a wrapper, then we definitely need to swap all types to their
2906 -- original concurrent status.
2909 or else Is_Primitive_Wrapper (Spec_N)
2911 -- Restore all references of corresponding record types to the
2912 -- original concurrent types.
2914 Replace_Types (To_Corresponding => False);
2915 Priv_Spec := Find_Corresponding_Spec (N, False);
2917 -- The current body truly belongs to a primitive declared between
2918 -- a private and a full view. We leave the modified body as is,
2919 -- and return the true spec.
2921 if Present (Priv_Spec)
2922 and then Is_Private_Primitive (Priv_Spec)
2927 -- In case that this is some sort of error, restore the original
2928 -- state of the body.
2930 Replace_Types (To_Corresponding => True);
2934 end Disambiguate_Spec;
2936 ----------------------------
2937 -- Exchange_Limited_Views --
2938 ----------------------------
2940 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
2941 Result : Elist_Id := No_Elist;
2943 procedure Detect_And_Exchange (Id : Entity_Id);
2944 -- Determine whether Id's type denotes an incomplete type associated
2945 -- with a limited with clause and exchange the limited view with the
2946 -- non-limited one when available. Note that the non-limited view
2947 -- may exist because of a with_clause in another unit in the context,
2948 -- but cannot be used because the current view of the enclosing unit
2949 -- is still a limited view.
2951 -------------------------
2952 -- Detect_And_Exchange --
2953 -------------------------
2955 procedure Detect_And_Exchange (Id : Entity_Id) is
2956 Typ : constant Entity_Id := Etype (Id);
2958 if From_Limited_With (Typ)
2959 and then Has_Non_Limited_View (Typ)
2960 and then not From_Limited_With (Scope (Typ))
2963 Result := New_Elmt_List;
2966 Prepend_Elmt (Typ, Result);
2967 Prepend_Elmt (Id, Result);
2968 Set_Etype (Id, Non_Limited_View (Typ));
2970 end Detect_And_Exchange;
2976 -- Start of processing for Exchange_Limited_Views
2979 -- Do not process subprogram bodies as they already use the non-
2980 -- limited view of types.
2982 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
2986 -- Examine all formals and swap views when applicable
2988 Formal := First_Formal (Subp_Id);
2989 while Present (Formal) loop
2990 Detect_And_Exchange (Formal);
2992 Next_Formal (Formal);
2995 -- Process the return type of a function
2997 if Ekind (Subp_Id) = E_Function then
2998 Detect_And_Exchange (Subp_Id);
3002 end Exchange_Limited_Views;
3004 -----------------------
3005 -- Freeze_Expr_Types --
3006 -----------------------
3008 procedure Freeze_Expr_Types (Spec_Id : Entity_Id) is
3009 function Cloned_Expression return Node_Id;
3010 -- Build a duplicate of the expression of the return statement that
3011 -- has no defining entities shared with the original expression.
3013 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result;
3014 -- Freeze all types referenced in the subtree rooted at Node
3016 -----------------------
3017 -- Cloned_Expression --
3018 -----------------------
3020 function Cloned_Expression return Node_Id is
3021 function Clone_Id (Node : Node_Id) return Traverse_Result;
3022 -- Tree traversal routine that clones the defining identifier of
3023 -- iterator and loop parameter specification nodes.
3029 function Clone_Id (Node : Node_Id) return Traverse_Result is
3031 if Nkind_In (Node, N_Iterator_Specification,
3032 N_Loop_Parameter_Specification)
3034 Set_Defining_Identifier (Node,
3035 New_Copy (Defining_Identifier (Node)));
3045 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id);
3049 Return_Stmt : constant Node_Id :=
3051 (Statements (Handled_Statement_Sequence (N)));
3054 -- Start of processing for Cloned_Expression
3057 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3059 -- We must duplicate the expression with semantic information to
3060 -- inherit the decoration of global entities in generic instances.
3062 Dup_Expr := New_Copy_Tree (Expression (Return_Stmt));
3064 -- Replace the defining identifier of iterators and loop param
3065 -- specifications by a clone to ensure that the cloned expression
3066 -- and the original expression don't have shared identifiers;
3067 -- otherwise, as part of the preanalysis of the expression, these
3068 -- shared identifiers may be left decorated with itypes which
3069 -- will not be available in the tree passed to the backend.
3071 Clone_Def_Ids (Dup_Expr);
3074 end Cloned_Expression;
3076 ----------------------
3077 -- Freeze_Type_Refs --
3078 ----------------------
3080 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is
3082 if Nkind (Node) = N_Identifier
3083 and then Present (Entity (Node))
3085 if Is_Type (Entity (Node)) then
3086 Freeze_Before (N, Entity (Node));
3088 elsif Ekind_In (Entity (Node), E_Component,
3092 Rec : constant Entity_Id := Scope (Entity (Node));
3095 -- Check that the enclosing record type can be frozen.
3096 -- This provides a better error message than generating
3097 -- primitives whose compilation fails much later. Refine
3098 -- the error message if possible.
3100 Check_Fully_Declared (Rec, Node);
3102 if Error_Posted (Node) then
3103 if Has_Private_Component (Rec) then
3105 ("\type& has private component", Node, Rec);
3109 Freeze_Before (N, Rec);
3114 -- Freezing an access type does not freeze the designated type,
3115 -- but freezing conversions between access to interfaces requires
3116 -- that the interface types themselves be frozen, so that dispatch
3117 -- table entities are properly created.
3119 -- Unclear whether a more general rule is needed ???
3121 elsif Nkind (Node) = N_Type_Conversion
3122 and then Is_Access_Type (Etype (Node))
3123 and then Is_Interface (Designated_Type (Etype (Node)))
3125 Freeze_Before (N, Designated_Type (Etype (Node)));
3129 end Freeze_Type_Refs;
3131 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs);
3135 Saved_First_Entity : constant Entity_Id := First_Entity (Spec_Id);
3136 Saved_Last_Entity : constant Entity_Id := Last_Entity (Spec_Id);
3137 Dup_Expr : constant Node_Id := Cloned_Expression;
3139 -- Start of processing for Freeze_Expr_Types
3142 -- Preanalyze a duplicate of the expression to have available the
3143 -- minimum decoration needed to locate referenced unfrozen types
3144 -- without adding any decoration to the function expression. This
3145 -- preanalysis is performed with errors disabled to avoid reporting
3146 -- spurious errors on Ghost entities (since the expression is not
3149 Push_Scope (Spec_Id);
3150 Install_Formals (Spec_Id);
3151 Ignore_Errors_Enable := Ignore_Errors_Enable + 1;
3153 Preanalyze_Spec_Expression (Dup_Expr, Etype (Spec_Id));
3155 Ignore_Errors_Enable := Ignore_Errors_Enable - 1;
3158 -- Restore certain attributes of Spec_Id since the preanalysis may
3159 -- have introduced itypes to this scope, thus modifying attributes
3160 -- First_Entity and Last_Entity.
3162 Set_First_Entity (Spec_Id, Saved_First_Entity);
3163 Set_Last_Entity (Spec_Id, Saved_Last_Entity);
3165 if Present (Last_Entity (Spec_Id)) then
3166 Set_Next_Entity (Last_Entity (Spec_Id), Empty);
3169 -- Freeze all types referenced in the expression
3171 Freeze_References (Dup_Expr);
3172 end Freeze_Expr_Types;
3174 -------------------------------------
3175 -- Is_Private_Concurrent_Primitive --
3176 -------------------------------------
3178 function Is_Private_Concurrent_Primitive
3179 (Subp_Id : Entity_Id) return Boolean
3181 Formal_Typ : Entity_Id;
3184 if Present (First_Formal (Subp_Id)) then
3185 Formal_Typ := Etype (First_Formal (Subp_Id));
3187 if Is_Concurrent_Record_Type (Formal_Typ) then
3188 if Is_Class_Wide_Type (Formal_Typ) then
3189 Formal_Typ := Root_Type (Formal_Typ);
3192 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3195 -- The type of the first formal is a concurrent tagged type with
3199 Is_Concurrent_Type (Formal_Typ)
3200 and then Is_Tagged_Type (Formal_Typ)
3201 and then Has_Private_Declaration (Formal_Typ);
3205 end Is_Private_Concurrent_Primitive;
3207 ---------------------------
3208 -- Restore_Limited_Views --
3209 ---------------------------
3211 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3212 Elmt : Elmt_Id := First_Elmt (Restore_List);
3216 while Present (Elmt) loop
3219 Set_Etype (Id, Node (Elmt));
3222 end Restore_Limited_Views;
3224 ----------------------------
3225 -- Set_Trivial_Subprogram --
3226 ----------------------------
3228 procedure Set_Trivial_Subprogram (N : Node_Id) is
3229 Nxt : constant Node_Id := Next (N);
3232 Set_Is_Trivial_Subprogram (Body_Id);
3234 if Present (Spec_Id) then
3235 Set_Is_Trivial_Subprogram (Spec_Id);
3239 and then Nkind (Nxt) = N_Simple_Return_Statement
3240 and then No (Next (Nxt))
3241 and then Present (Expression (Nxt))
3242 and then Is_Entity_Name (Expression (Nxt))
3244 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3246 end Set_Trivial_Subprogram;
3248 ---------------------------------
3249 -- Verify_Overriding_Indicator --
3250 ---------------------------------
3252 procedure Verify_Overriding_Indicator is
3254 if Must_Override (Body_Spec) then
3255 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3256 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3260 elsif not Present (Overridden_Operation (Spec_Id)) then
3262 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3264 -- Overriding indicators aren't allowed for protected subprogram
3265 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3266 -- this to a warning if -gnatd.E is enabled.
3268 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3269 Error_Msg_Warn := Error_To_Warning;
3271 ("<<overriding indicator not allowed for protected "
3272 & "subprogram body", Body_Spec);
3275 elsif Must_Not_Override (Body_Spec) then
3276 if Present (Overridden_Operation (Spec_Id)) then
3278 ("subprogram& overrides inherited operation",
3279 Body_Spec, Spec_Id);
3281 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3282 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3285 ("subprogram& overrides predefined operator ",
3286 Body_Spec, Spec_Id);
3288 -- Overriding indicators aren't allowed for protected subprogram
3289 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3290 -- this to a warning if -gnatd.E is enabled.
3292 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3293 Error_Msg_Warn := Error_To_Warning;
3296 ("<<overriding indicator not allowed "
3297 & "for protected subprogram body", Body_Spec);
3299 -- If this is not a primitive operation, then the overriding
3300 -- indicator is altogether illegal.
3302 elsif not Is_Primitive (Spec_Id) then
3304 ("overriding indicator only allowed "
3305 & "if subprogram is primitive", Body_Spec);
3308 -- If checking the style rule and the operation overrides, then
3309 -- issue a warning about a missing overriding_indicator. Protected
3310 -- subprogram bodies are excluded from this style checking, since
3311 -- they aren't primitives (even though their declarations can
3312 -- override) and aren't allowed to have an overriding_indicator.
3315 and then Present (Overridden_Operation (Spec_Id))
3316 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3318 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3319 Style.Missing_Overriding (N, Body_Id);
3322 and then Can_Override_Operator (Spec_Id)
3323 and then not In_Predefined_Unit (Spec_Id)
3325 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3326 Style.Missing_Overriding (N, Body_Id);
3328 end Verify_Overriding_Indicator;
3332 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3333 Saved_ISMP : constant Boolean :=
3334 Ignore_SPARK_Mode_Pragmas_In_Instance;
3335 -- Save the Ghost and SPARK mode-related data to restore on exit
3337 -- Start of processing for Analyze_Subprogram_Body_Helper
3340 -- A [generic] subprogram body "freezes" the contract of the nearest
3341 -- enclosing package body and all other contracts encountered in the
3342 -- same declarative part up to and excluding the subprogram body:
3344 -- package body Nearest_Enclosing_Package
3345 -- with Refined_State => (State => Constit)
3349 -- procedure Freezes_Enclosing_Package_Body
3350 -- with Refined_Depends => (Input => Constit) ...
3352 -- This ensures that any annotations referenced by the contract of the
3353 -- [generic] subprogram body are available. This form of "freezing" is
3354 -- decoupled from the usual Freeze_xxx mechanism because it must also
3355 -- work in the context of generics where normal freezing is disabled.
3357 -- Only bodies coming from source should cause this type of "freezing".
3358 -- Expression functions that act as bodies and complete an initial
3359 -- declaration must be included in this category, hence the use of
3362 if Comes_From_Source (Original_Node (N)) then
3363 Analyze_Previous_Contracts (N);
3366 -- Generic subprograms are handled separately. They always have a
3367 -- generic specification. Determine whether current scope has a
3368 -- previous declaration.
3370 -- If the subprogram body is defined within an instance of the same
3371 -- name, the instance appears as a package renaming, and will be hidden
3372 -- within the subprogram.
3374 if Present (Prev_Id)
3375 and then not Is_Overloadable (Prev_Id)
3376 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3377 or else Comes_From_Source (Prev_Id))
3379 if Is_Generic_Subprogram (Prev_Id) then
3382 -- A subprogram body is Ghost when it is stand alone and subject
3383 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3384 -- the mode now to ensure that any nodes generated during analysis
3385 -- and expansion are properly marked as Ghost.
3387 Mark_And_Set_Ghost_Body (N, Spec_Id);
3389 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3390 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3392 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3394 if Nkind (N) = N_Subprogram_Body then
3395 HSS := Handled_Statement_Sequence (N);
3396 Check_Missing_Return;
3401 -- Otherwise a previous entity conflicts with the subprogram name.
3402 -- Attempting to enter name will post error.
3405 Enter_Name (Body_Id);
3409 -- Non-generic case, find the subprogram declaration, if one was seen,
3410 -- or enter new overloaded entity in the current scope. If the
3411 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3412 -- part of the context of one of its subunits. No need to redo the
3415 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3419 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3421 if Nkind (N) = N_Subprogram_Body_Stub
3422 or else No (Corresponding_Spec (N))
3424 if Is_Private_Concurrent_Primitive (Body_Id) then
3425 Spec_Id := Disambiguate_Spec;
3427 -- A subprogram body is Ghost when it is stand alone and
3428 -- subject to pragma Ghost or when the corresponding spec is
3429 -- Ghost. Set the mode now to ensure that any nodes generated
3430 -- during analysis and expansion are properly marked as Ghost.
3432 Mark_And_Set_Ghost_Body (N, Spec_Id);
3435 Spec_Id := Find_Corresponding_Spec (N);
3437 -- A subprogram body is Ghost when it is stand alone and
3438 -- subject to pragma Ghost or when the corresponding spec is
3439 -- Ghost. Set the mode now to ensure that any nodes generated
3440 -- during analysis and expansion are properly marked as Ghost.
3442 Mark_And_Set_Ghost_Body (N, Spec_Id);
3444 -- In GNATprove mode, if the body has no previous spec, create
3445 -- one so that the inlining machinery can operate properly.
3446 -- Transfer aspects, if any, to the new spec, so that they
3447 -- are legal and can be processed ahead of the body.
3448 -- We make two copies of the given spec, one for the new
3449 -- declaration, and one for the body.
3451 if No (Spec_Id) and then GNATprove_Mode
3453 -- Inlining does not apply during pre-analysis of code
3455 and then Full_Analysis
3457 -- Inlining only applies to full bodies, not stubs
3459 and then Nkind (N) /= N_Subprogram_Body_Stub
3461 -- Inlining only applies to bodies in the source code, not to
3462 -- those generated by the compiler. In particular, expression
3463 -- functions, whose body is generated by the compiler, are
3464 -- treated specially by GNATprove.
3466 and then Comes_From_Source (Body_Id)
3468 -- This cannot be done for a compilation unit, which is not
3469 -- in a context where we can insert a new spec.
3471 and then Is_List_Member (N)
3473 -- Inlining only applies to subprograms without contracts,
3474 -- as a contract is a sign that GNATprove should perform a
3475 -- modular analysis of the subprogram instead of a contextual
3476 -- analysis at each call site. The same test is performed in
3477 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3478 -- here in another form (because the contract has not been
3479 -- attached to the body) to avoid front-end errors in case
3480 -- pragmas are used instead of aspects, because the
3481 -- corresponding pragmas in the body would not be transferred
3482 -- to the spec, leading to legality errors.
3484 and then not Body_Has_Contract
3485 and then not Inside_A_Generic
3487 Build_Subprogram_Declaration;
3489 -- If this is a function that returns a constrained array, and
3490 -- we are generating SPARK_For_C, create subprogram declaration
3491 -- to simplify subsequent C generation.
3494 and then Modify_Tree_For_C
3495 and then Nkind (Body_Spec) = N_Function_Specification
3496 and then Is_Array_Type (Etype (Body_Id))
3497 and then Is_Constrained (Etype (Body_Id))
3499 Build_Subprogram_Declaration;
3503 -- If this is a duplicate body, no point in analyzing it
3505 if Error_Posted (N) then
3509 -- A subprogram body should cause freezing of its own declaration,
3510 -- but if there was no previous explicit declaration, then the
3511 -- subprogram will get frozen too late (there may be code within
3512 -- the body that depends on the subprogram having been frozen,
3513 -- such as uses of extra formals), so we force it to be frozen
3514 -- here. Same holds if the body and spec are compilation units.
3515 -- Finally, if the return type is an anonymous access to protected
3516 -- subprogram, it must be frozen before the body because its
3517 -- expansion has generated an equivalent type that is used when
3518 -- elaborating the body.
3520 -- An exception in the case of Ada 2012, AI05-177: The bodies
3521 -- created for expression functions do not freeze.
3524 and then Nkind (Original_Node (N)) /= N_Expression_Function
3526 Freeze_Before (N, Body_Id);
3528 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3529 Freeze_Before (N, Spec_Id);
3531 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3532 Freeze_Before (N, Etype (Body_Id));
3536 Spec_Id := Corresponding_Spec (N);
3538 -- A subprogram body is Ghost when it is stand alone and subject
3539 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3540 -- the mode now to ensure that any nodes generated during analysis
3541 -- and expansion are properly marked as Ghost.
3543 Mark_And_Set_Ghost_Body (N, Spec_Id);
3547 -- Previously we scanned the body to look for nested subprograms, and
3548 -- rejected an inline directive if nested subprograms were present,
3549 -- because the back-end would generate conflicting symbols for the
3550 -- nested bodies. This is now unnecessary.
3552 -- Look ahead to recognize a pragma Inline that appears after the body
3554 Check_Inline_Pragma (Spec_Id);
3556 -- Deal with special case of a fully private operation in the body of
3557 -- the protected type. We must create a declaration for the subprogram,
3558 -- in order to attach the protected subprogram that will be used in
3559 -- internal calls. We exclude compiler generated bodies from the
3560 -- expander since the issue does not arise for those cases.
3563 and then Comes_From_Source (N)
3564 and then Is_Protected_Type (Current_Scope)
3566 Spec_Id := Build_Private_Protected_Declaration (N);
3569 -- If we are generating C and this is a function returning a constrained
3570 -- array type for which we must create a procedure with an extra out
3571 -- parameter, build and analyze the body now. The procedure declaration
3572 -- has already been created. We reuse the source body of the function,
3573 -- because in an instance it may contain global references that cannot
3574 -- be reanalyzed. The source function itself is not used any further,
3575 -- so we mark it as having a completion. If the subprogram is a stub the
3576 -- transformation is done later, when the proper body is analyzed.
3579 and then Modify_Tree_For_C
3580 and then Present (Spec_Id)
3581 and then Ekind (Spec_Id) = E_Function
3582 and then Nkind (N) /= N_Subprogram_Body_Stub
3583 and then Rewritten_For_C (Spec_Id)
3585 Set_Has_Completion (Spec_Id);
3587 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3590 -- The entity for the created procedure must remain invisible, so it
3591 -- does not participate in resolution of subsequent references to the
3594 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3598 -- If a separate spec is present, then deal with freezing issues
3600 if Present (Spec_Id) then
3601 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3602 Verify_Overriding_Indicator;
3604 -- In general, the spec will be frozen when we start analyzing the
3605 -- body. However, for internally generated operations, such as
3606 -- wrapper functions for inherited operations with controlling
3607 -- results, the spec may not have been frozen by the time we expand
3608 -- the freeze actions that include the bodies. In particular, extra
3609 -- formals for accessibility or for return-in-place may need to be
3610 -- generated. Freeze nodes, if any, are inserted before the current
3611 -- body. These freeze actions are also needed in ASIS mode and in
3612 -- Compile_Only mode to enable the proper back-end type annotations.
3613 -- They are necessary in any case to insure order of elaboration
3616 if not Is_Frozen (Spec_Id)
3617 and then (Expander_Active
3619 or else (Operating_Mode = Check_Semantics
3620 and then Serious_Errors_Detected = 0))
3622 Set_Has_Delayed_Freeze (Spec_Id);
3623 Freeze_Before (N, Spec_Id);
3625 -- AI12-0103: At the occurrence of an expression function
3626 -- declaration that is a completion, its expression causes
3629 if Has_Completion (Spec_Id)
3630 and then Nkind (N) = N_Subprogram_Body
3631 and then Was_Expression_Function (N)
3633 Freeze_Expr_Types (Spec_Id);
3638 -- If the subprogram has a class-wide clone, build its body as a copy
3639 -- of the original body, and rewrite body of original subprogram as a
3640 -- wrapper that calls the clone.
3642 if Present (Spec_Id)
3643 and then Present (Class_Wide_Clone (Spec_Id))
3644 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3646 Build_Class_Wide_Clone_Body (Spec_Id, N);
3648 -- This is the new body for the existing primitive operation
3650 Rewrite (N, Build_Class_Wide_Clone_Call
3651 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3652 Set_Has_Completion (Spec_Id, False);
3657 -- Place subprogram on scope stack, and make formals visible. If there
3658 -- is a spec, the visible entity remains that of the spec.
3660 if Present (Spec_Id) then
3661 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3663 if Is_Child_Unit (Spec_Id) then
3664 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3668 Style.Check_Identifier (Body_Id, Spec_Id);
3671 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3672 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3674 if Is_Abstract_Subprogram (Spec_Id) then
3675 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3679 Set_Convention (Body_Id, Convention (Spec_Id));
3680 Set_Has_Completion (Spec_Id);
3682 if Is_Protected_Type (Scope (Spec_Id)) then
3683 Prot_Typ := Scope (Spec_Id);
3686 -- If this is a body generated for a renaming, do not check for
3687 -- full conformance. The check is redundant, because the spec of
3688 -- the body is a copy of the spec in the renaming declaration,
3689 -- and the test can lead to spurious errors on nested defaults.
3691 if Present (Spec_Decl)
3692 and then not Comes_From_Source (N)
3694 (Nkind (Original_Node (Spec_Decl)) =
3695 N_Subprogram_Renaming_Declaration
3696 or else (Present (Corresponding_Body (Spec_Decl))
3698 Nkind (Unit_Declaration_Node
3699 (Corresponding_Body (Spec_Decl))) =
3700 N_Subprogram_Renaming_Declaration))
3704 -- Conversely, the spec may have been generated for specless body
3705 -- with an inline pragma. The entity comes from source, which is
3706 -- both semantically correct and necessary for proper inlining.
3707 -- The subprogram declaration itself is not in the source.
3709 elsif Comes_From_Source (N)
3710 and then Present (Spec_Decl)
3711 and then not Comes_From_Source (Spec_Decl)
3712 and then Has_Pragma_Inline (Spec_Id)
3719 Fully_Conformant, True, Conformant, Body_Id);
3722 -- If the body is not fully conformant, we have to decide if we
3723 -- should analyze it or not. If it has a really messed up profile
3724 -- then we probably should not analyze it, since we will get too
3725 -- many bogus messages.
3727 -- Our decision is to go ahead in the non-fully conformant case
3728 -- only if it is at least mode conformant with the spec. Note
3729 -- that the call to Check_Fully_Conformant has issued the proper
3730 -- error messages to complain about the lack of conformance.
3733 and then not Mode_Conformant (Body_Id, Spec_Id)
3739 if Spec_Id /= Body_Id then
3740 Reference_Body_Formals (Spec_Id, Body_Id);
3743 Set_Ekind (Body_Id, E_Subprogram_Body);
3745 if Nkind (N) = N_Subprogram_Body_Stub then
3746 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3751 Set_Corresponding_Spec (N, Spec_Id);
3753 -- Ada 2005 (AI-345): If the operation is a primitive operation
3754 -- of a concurrent type, the type of the first parameter has been
3755 -- replaced with the corresponding record, which is the proper
3756 -- run-time structure to use. However, within the body there may
3757 -- be uses of the formals that depend on primitive operations
3758 -- of the type (in particular calls in prefixed form) for which
3759 -- we need the original concurrent type. The operation may have
3760 -- several controlling formals, so the replacement must be done
3763 if Comes_From_Source (Spec_Id)
3764 and then Present (First_Entity (Spec_Id))
3765 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3766 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3767 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3768 and then Present (Corresponding_Concurrent_Type
3769 (Etype (First_Entity (Spec_Id))))
3772 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3776 Form := First_Formal (Spec_Id);
3777 while Present (Form) loop
3778 if Etype (Form) = Typ then
3779 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3787 -- Make the formals visible, and place subprogram on scope stack.
3788 -- This is also the point at which we set Last_Real_Spec_Entity
3789 -- to mark the entities which will not be moved to the body.
3791 Install_Formals (Spec_Id);
3792 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3794 -- Within an instance, add local renaming declarations so that
3795 -- gdb can retrieve the values of actuals more easily. This is
3796 -- only relevant if generating code (and indeed we definitely
3797 -- do not want these definitions -gnatc mode, because that would
3800 if Is_Generic_Instance (Spec_Id)
3801 and then Is_Wrapper_Package (Current_Scope)
3802 and then Expander_Active
3804 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3807 Push_Scope (Spec_Id);
3809 -- Make sure that the subprogram is immediately visible. For
3810 -- child units that have no separate spec this is indispensable.
3811 -- Otherwise it is safe albeit redundant.
3813 Set_Is_Immediately_Visible (Spec_Id);
3816 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3817 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3818 Set_Scope (Body_Id, Scope (Spec_Id));
3820 -- Case of subprogram body with no previous spec
3823 -- Check for style warning required
3827 -- Only apply check for source level subprograms for which checks
3828 -- have not been suppressed.
3830 and then Comes_From_Source (Body_Id)
3831 and then not Suppress_Style_Checks (Body_Id)
3833 -- No warnings within an instance
3835 and then not In_Instance
3837 -- No warnings for expression functions
3839 and then Nkind (Original_Node (N)) /= N_Expression_Function
3841 Style.Body_With_No_Spec (N);
3844 New_Overloaded_Entity (Body_Id);
3846 if Nkind (N) /= N_Subprogram_Body_Stub then
3847 Set_Acts_As_Spec (N);
3848 Generate_Definition (Body_Id);
3850 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3852 -- If the body is an entry wrapper created for an entry with
3853 -- preconditions, it must be compiled in the context of the
3854 -- enclosing synchronized object, because it may mention other
3855 -- operations of the type.
3857 if Is_Entry_Wrapper (Body_Id) then
3859 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3862 Install_Declarations (Prot);
3866 Install_Formals (Body_Id);
3868 Push_Scope (Body_Id);
3871 -- For stubs and bodies with no previous spec, generate references to
3874 Generate_Reference_To_Formals (Body_Id);
3877 -- Entry barrier functions are generated outside the protected type and
3878 -- should not carry the SPARK_Mode of the enclosing context.
3880 if Nkind (N) = N_Subprogram_Body
3881 and then Is_Entry_Barrier_Function (N)
3885 -- The body is generated as part of expression function expansion. When
3886 -- the expression function appears in the visible declarations of a
3887 -- package, the body is added to the private declarations. Since both
3888 -- declarative lists may be subject to a different SPARK_Mode, inherit
3889 -- the mode of the spec.
3891 -- package P with SPARK_Mode is
3892 -- function Expr_Func ... is (...); -- original
3893 -- [function Expr_Func ...;] -- generated spec
3896 -- pragma SPARK_Mode (Off);
3897 -- [function Expr_Func ... is return ...;] -- generated body
3898 -- end P; -- mode is ON
3900 elsif not Comes_From_Source (N)
3901 and then Present (Spec_Id)
3902 and then Is_Expression_Function (Spec_Id)
3904 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
3905 Set_SPARK_Pragma_Inherited
3906 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
3908 -- Set the SPARK_Mode from the current context (may be overwritten later
3909 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
3910 -- initially on a stand-alone subprogram body, but is then relocated to
3911 -- a generated corresponding spec. In this scenario the mode is shared
3912 -- between the spec and body.
3914 elsif No (SPARK_Pragma (Body_Id)) then
3915 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
3916 Set_SPARK_Pragma_Inherited (Body_Id);
3919 -- A subprogram body may be instantiated or inlined at a later pass.
3920 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
3921 -- applied to the initial declaration of the body.
3923 if Present (Spec_Id) then
3924 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
3925 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
3929 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
3930 -- case the body is instantiated or inlined later and out of context.
3931 -- The body uses this attribute to restore the value of the global
3934 if Ignore_SPARK_Mode_Pragmas_In_Instance then
3935 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
3937 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
3938 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
3942 -- If this is the proper body of a stub, we must verify that the stub
3943 -- conforms to the body, and to the previous spec if one was present.
3944 -- We know already that the body conforms to that spec. This test is
3945 -- only required for subprograms that come from source.
3947 if Nkind (Parent (N)) = N_Subunit
3948 and then Comes_From_Source (N)
3949 and then not Error_Posted (Body_Id)
3950 and then Nkind (Corresponding_Stub (Parent (N))) =
3951 N_Subprogram_Body_Stub
3954 Old_Id : constant Entity_Id :=
3956 (Specification (Corresponding_Stub (Parent (N))));
3958 Conformant : Boolean := False;
3961 if No (Spec_Id) then
3962 Check_Fully_Conformant (Body_Id, Old_Id);
3966 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
3968 if not Conformant then
3970 -- The stub was taken to be a new declaration. Indicate that
3973 Set_Has_Completion (Old_Id, False);
3979 Set_Has_Completion (Body_Id);
3980 Check_Eliminated (Body_Id);
3982 -- Analyze any aspect specifications that appear on the subprogram body
3983 -- stub. Stop the analysis now as the stub does not have a declarative
3984 -- or a statement part, and it cannot be inlined.
3986 if Nkind (N) = N_Subprogram_Body_Stub then
3987 if Has_Aspects (N) then
3988 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
3996 -- Note: Normally we don't do any inlining if expansion is off, since
3997 -- we won't generate code in any case. An exception arises in GNATprove
3998 -- mode where we want to expand some calls in place, even with expansion
3999 -- disabled, since the inlining eases formal verification.
4001 if not GNATprove_Mode
4002 and then Expander_Active
4003 and then Serious_Errors_Detected = 0
4004 and then Present (Spec_Id)
4005 and then Has_Pragma_Inline (Spec_Id)
4007 -- Legacy implementation (relying on front-end inlining)
4009 if not Back_End_Inlining then
4010 if (Has_Pragma_Inline_Always (Spec_Id)
4011 and then not Opt.Disable_FE_Inline_Always)
4012 or else (Front_End_Inlining
4013 and then not Opt.Disable_FE_Inline)
4015 Build_Body_To_Inline (N, Spec_Id);
4018 -- New implementation (relying on back-end inlining)
4021 if Has_Pragma_Inline_Always (Spec_Id)
4022 or else Optimization_Level > 0
4024 -- Handle function returning an unconstrained type
4026 if Comes_From_Source (Body_Id)
4027 and then Ekind (Spec_Id) = E_Function
4028 and then Returns_Unconstrained_Type (Spec_Id)
4030 -- If function builds in place, i.e. returns a limited type,
4031 -- inlining cannot be done.
4033 and then not Is_Limited_Type (Etype (Spec_Id))
4035 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4039 Subp_Body : constant Node_Id :=
4040 Unit_Declaration_Node (Body_Id);
4041 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4044 -- Do not pass inlining to the backend if the subprogram
4045 -- has declarations or statements which cannot be inlined
4046 -- by the backend. This check is done here to emit an
4047 -- error instead of the generic warning message reported
4048 -- by the GCC backend (ie. "function might not be
4051 if Present (Subp_Decl)
4052 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4056 elsif Has_Excluded_Statement
4059 (Handled_Statement_Sequence (Subp_Body)))
4063 -- If the backend inlining is available then at this
4064 -- stage we only have to mark the subprogram as inlined.
4065 -- The expander will take care of registering it in the
4066 -- table of subprograms inlined by the backend a part of
4067 -- processing calls to it (cf. Expand_Call)
4070 Set_Is_Inlined (Spec_Id);
4077 -- In GNATprove mode, inline only when there is a separate subprogram
4078 -- declaration for now, as inlining of subprogram bodies acting as
4079 -- declarations, or subprogram stubs, are not supported by front-end
4080 -- inlining. This inlining should occur after analysis of the body, so
4081 -- that it is known whether the value of SPARK_Mode, which can be
4082 -- defined by a pragma inside the body, is applicable to the body.
4083 -- Inlining can be disabled with switch -gnatdm
4085 elsif GNATprove_Mode
4086 and then Full_Analysis
4087 and then not Inside_A_Generic
4088 and then Present (Spec_Id)
4090 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4091 and then Body_Has_SPARK_Mode_On
4092 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4093 and then not Body_Has_Contract
4094 and then not Debug_Flag_M
4096 Build_Body_To_Inline (N, Spec_Id);
4099 -- When generating code, inherited pre/postconditions are handled when
4100 -- expanding the corresponding contract.
4102 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4103 -- of the specification we have to install the private withed units.
4104 -- This holds for child units as well.
4106 if Is_Compilation_Unit (Body_Id)
4107 or else Nkind (Parent (N)) = N_Compilation_Unit
4109 Install_Private_With_Clauses (Body_Id);
4112 Check_Anonymous_Return;
4114 -- Set the Protected_Formal field of each extra formal of the protected
4115 -- subprogram to reference the corresponding extra formal of the
4116 -- subprogram that implements it. For regular formals this occurs when
4117 -- the protected subprogram's declaration is expanded, but the extra
4118 -- formals don't get created until the subprogram is frozen. We need to
4119 -- do this before analyzing the protected subprogram's body so that any
4120 -- references to the original subprogram's extra formals will be changed
4121 -- refer to the implementing subprogram's formals (see Expand_Formal).
4123 if Present (Spec_Id)
4124 and then Is_Protected_Type (Scope (Spec_Id))
4125 and then Present (Protected_Body_Subprogram (Spec_Id))
4128 Impl_Subp : constant Entity_Id :=
4129 Protected_Body_Subprogram (Spec_Id);
4130 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4131 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4134 while Present (Prot_Ext_Formal) loop
4135 pragma Assert (Present (Impl_Ext_Formal));
4136 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4137 Next_Formal_With_Extras (Prot_Ext_Formal);
4138 Next_Formal_With_Extras (Impl_Ext_Formal);
4143 -- Now we can go on to analyze the body
4145 HSS := Handled_Statement_Sequence (N);
4146 Set_Actual_Subtypes (N, Current_Scope);
4148 -- Add a declaration for the Protection object, renaming declarations
4149 -- for discriminals and privals and finally a declaration for the entry
4150 -- family index (if applicable). This form of early expansion is done
4151 -- when the Expander is active because Install_Private_Data_Declarations
4152 -- references entities which were created during regular expansion. The
4153 -- subprogram entity must come from source, and not be an internally
4154 -- generated subprogram.
4157 and then Present (Prot_Typ)
4158 and then Present (Spec_Id)
4159 and then Comes_From_Source (Spec_Id)
4160 and then not Is_Eliminated (Spec_Id)
4162 Install_Private_Data_Declarations
4163 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4166 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4167 -- may now appear in parameter and result profiles. Since the analysis
4168 -- of a subprogram body may use the parameter and result profile of the
4169 -- spec, swap any limited views with their non-limited counterpart.
4171 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4172 Exch_Views := Exchange_Limited_Views (Spec_Id);
4175 -- If the return type is an anonymous access type whose designated type
4176 -- is the limited view of a class-wide type and the non-limited view is
4177 -- available, update the return type accordingly.
4179 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4185 Rtyp := Etype (Spec_Id);
4187 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4188 Etyp := Directly_Designated_Type (Rtyp);
4190 if Is_Class_Wide_Type (Etyp)
4191 and then From_Limited_With (Etyp)
4194 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4200 -- Analyze any aspect specifications that appear on the subprogram body
4202 if Has_Aspects (N) then
4203 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4206 Analyze_Declarations (Declarations (N));
4208 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4210 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4211 if Present (SPARK_Pragma (Spec_Id)) then
4212 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4214 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4216 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4217 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4218 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4220 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4223 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4227 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4228 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4229 Error_Msg_Sloc := Sloc (Spec_Id);
4231 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4235 -- A subprogram body "freezes" its own contract. Analyze the contract
4236 -- after the declarations of the body have been processed as pragmas
4237 -- are now chained on the contract of the subprogram body.
4239 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4241 -- Check completion, and analyze the statements
4244 Inspect_Deferred_Constant_Completion (Declarations (N));
4247 -- Deal with end of scope processing for the body
4249 Process_End_Label (HSS, 't', Current_Scope);
4252 -- If we are compiling an entry wrapper, remove the enclosing
4253 -- synchronized object from the stack.
4255 if Is_Entry_Wrapper (Body_Id) then
4259 Check_Subprogram_Order (N);
4260 Set_Analyzed (Body_Id);
4262 -- If we have a separate spec, then the analysis of the declarations
4263 -- caused the entities in the body to be chained to the spec id, but
4264 -- we want them chained to the body id. Only the formal parameters
4265 -- end up chained to the spec id in this case.
4267 if Present (Spec_Id) then
4269 -- We must conform to the categorization of our spec
4271 Validate_Categorization_Dependency (N, Spec_Id);
4273 -- And if this is a child unit, the parent units must conform
4275 if Is_Child_Unit (Spec_Id) then
4276 Validate_Categorization_Dependency
4277 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4280 -- Here is where we move entities from the spec to the body
4282 -- Case where there are entities that stay with the spec
4284 if Present (Last_Real_Spec_Entity) then
4286 -- No body entities (happens when the only real spec entities come
4287 -- from precondition and postcondition pragmas).
4289 if No (Last_Entity (Body_Id)) then
4290 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4292 -- Body entities present (formals), so chain stuff past them
4296 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4299 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4300 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4301 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4303 -- Case where there are no spec entities, in this case there can be
4304 -- no body entities either, so just move everything.
4306 -- If the body is generated for an expression function, it may have
4307 -- been preanalyzed already, if 'access was applied to it.
4310 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4311 N_Expression_Function
4313 pragma Assert (No (Last_Entity (Body_Id)));
4317 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4318 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4319 Set_First_Entity (Spec_Id, Empty);
4320 Set_Last_Entity (Spec_Id, Empty);
4324 Check_Missing_Return;
4326 -- Now we are going to check for variables that are never modified in
4327 -- the body of the procedure. But first we deal with a special case
4328 -- where we want to modify this check. If the body of the subprogram
4329 -- starts with a raise statement or its equivalent, or if the body
4330 -- consists entirely of a null statement, then it is pretty obvious that
4331 -- it is OK to not reference the parameters. For example, this might be
4332 -- the following common idiom for a stubbed function: statement of the
4333 -- procedure raises an exception. In particular this deals with the
4334 -- common idiom of a stubbed function, which appears something like:
4336 -- function F (A : Integer) return Some_Type;
4339 -- raise Program_Error;
4343 -- Here the purpose of X is simply to satisfy the annoying requirement
4344 -- in Ada that there be at least one return, and we certainly do not
4345 -- want to go posting warnings on X that it is not initialized. On
4346 -- the other hand, if X is entirely unreferenced that should still
4349 -- What we do is to detect these cases, and if we find them, flag the
4350 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4351 -- suppress unwanted warnings. For the case of the function stub above
4352 -- we have a special test to set X as apparently assigned to suppress
4359 -- Skip initial labels (for one thing this occurs when we are in
4360 -- front-end ZCX mode, but in any case it is irrelevant), and also
4361 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
4363 Stm := First (Statements (HSS));
4364 while Nkind (Stm) = N_Label
4365 or else Nkind (Stm) in N_Push_xxx_Label
4370 -- Do the test on the original statement before expansion
4373 Ostm : constant Node_Id := Original_Node (Stm);
4376 -- If explicit raise statement, turn on flag
4378 if Nkind (Ostm) = N_Raise_Statement then
4379 Set_Trivial_Subprogram (Stm);
4381 -- If null statement, and no following statements, turn on flag
4383 elsif Nkind (Stm) = N_Null_Statement
4384 and then Comes_From_Source (Stm)
4385 and then No (Next (Stm))
4387 Set_Trivial_Subprogram (Stm);
4389 -- Check for explicit call cases which likely raise an exception
4391 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4392 if Is_Entity_Name (Name (Ostm)) then
4394 Ent : constant Entity_Id := Entity (Name (Ostm));
4397 -- If the procedure is marked No_Return, then likely it
4398 -- raises an exception, but in any case it is not coming
4399 -- back here, so turn on the flag.
4402 and then Ekind (Ent) = E_Procedure
4403 and then No_Return (Ent)
4405 Set_Trivial_Subprogram (Stm);
4413 -- Check for variables that are never modified
4420 -- If there is a separate spec, then transfer Never_Set_In_Source
4421 -- flags from out parameters to the corresponding entities in the
4422 -- body. The reason we do that is we want to post error flags on
4423 -- the body entities, not the spec entities.
4425 if Present (Spec_Id) then
4426 E1 := First_Entity (Spec_Id);
4427 while Present (E1) loop
4428 if Ekind (E1) = E_Out_Parameter then
4429 E2 := First_Entity (Body_Id);
4430 while Present (E2) loop
4431 exit when Chars (E1) = Chars (E2);
4435 if Present (E2) then
4436 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4444 -- Check references in body
4446 Check_References (Body_Id);
4449 -- Check for nested subprogram, and mark outer level subprogram if so
4455 if Present (Spec_Id) then
4462 Ent := Enclosing_Subprogram (Ent);
4463 exit when No (Ent) or else Is_Subprogram (Ent);
4466 if Present (Ent) then
4467 Set_Has_Nested_Subprogram (Ent);
4471 -- Restore the limited views in the spec, if any, to let the back end
4472 -- process it without running into circularities.
4474 if Exch_Views /= No_Elist then
4475 Restore_Limited_Views (Exch_Views);
4478 if Present (Desig_View) then
4479 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4483 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4484 Restore_Ghost_Mode (Saved_GM);
4485 end Analyze_Subprogram_Body_Helper;
4487 ------------------------------------
4488 -- Analyze_Subprogram_Declaration --
4489 ------------------------------------
4491 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4492 Scop : constant Entity_Id := Current_Scope;
4493 Designator : Entity_Id;
4495 Is_Completion : Boolean;
4496 -- Indicates whether a null procedure declaration is a completion
4499 -- Null procedures are not allowed in SPARK
4501 if Nkind (Specification (N)) = N_Procedure_Specification
4502 and then Null_Present (Specification (N))
4504 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4506 -- Null procedures are allowed in protected types, following the
4507 -- recent AI12-0147.
4509 if Is_Protected_Type (Current_Scope)
4510 and then Ada_Version < Ada_2012
4512 Error_Msg_N ("protected operation cannot be a null procedure", N);
4515 Analyze_Null_Procedure (N, Is_Completion);
4517 -- The null procedure acts as a body, nothing further is needed
4519 if Is_Completion then
4524 Designator := Analyze_Subprogram_Specification (Specification (N));
4526 -- A reference may already have been generated for the unit name, in
4527 -- which case the following call is redundant. However it is needed for
4528 -- declarations that are the rewriting of an expression function.
4530 Generate_Definition (Designator);
4532 -- Set the SPARK mode from the current context (may be overwritten later
4533 -- with explicit pragma). This is not done for entry barrier functions
4534 -- because they are generated outside the protected type and should not
4535 -- carry the mode of the enclosing context.
4537 if Nkind (N) = N_Subprogram_Declaration
4538 and then Is_Entry_Barrier_Function (N)
4542 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4543 Set_SPARK_Pragma_Inherited (Designator);
4546 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4547 -- the body of this subprogram is instantiated or inlined later and out
4548 -- of context. The body uses this attribute to restore the value of the
4551 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4552 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4555 if Debug_Flag_C then
4556 Write_Str ("==> subprogram spec ");
4557 Write_Name (Chars (Designator));
4558 Write_Str (" from ");
4559 Write_Location (Sloc (N));
4564 Validate_RCI_Subprogram_Declaration (N);
4565 New_Overloaded_Entity (Designator);
4566 Check_Delayed_Subprogram (Designator);
4568 -- If the type of the first formal of the current subprogram is a non-
4569 -- generic tagged private type, mark the subprogram as being a private
4570 -- primitive. Ditto if this is a function with controlling result, and
4571 -- the return type is currently private. In both cases, the type of the
4572 -- controlling argument or result must be in the current scope for the
4573 -- operation to be primitive.
4575 if Has_Controlling_Result (Designator)
4576 and then Is_Private_Type (Etype (Designator))
4577 and then Scope (Etype (Designator)) = Current_Scope
4578 and then not Is_Generic_Actual_Type (Etype (Designator))
4580 Set_Is_Private_Primitive (Designator);
4582 elsif Present (First_Formal (Designator)) then
4584 Formal_Typ : constant Entity_Id :=
4585 Etype (First_Formal (Designator));
4587 Set_Is_Private_Primitive (Designator,
4588 Is_Tagged_Type (Formal_Typ)
4589 and then Scope (Formal_Typ) = Current_Scope
4590 and then Is_Private_Type (Formal_Typ)
4591 and then not Is_Generic_Actual_Type (Formal_Typ));
4595 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4598 if Ada_Version >= Ada_2005
4599 and then Comes_From_Source (N)
4600 and then Is_Dispatching_Operation (Designator)
4607 if Has_Controlling_Result (Designator) then
4608 Etyp := Etype (Designator);
4611 E := First_Entity (Designator);
4613 and then Is_Formal (E)
4614 and then not Is_Controlling_Formal (E)
4622 if Is_Access_Type (Etyp) then
4623 Etyp := Directly_Designated_Type (Etyp);
4626 if Is_Interface (Etyp)
4627 and then not Is_Abstract_Subprogram (Designator)
4628 and then not (Ekind (Designator) = E_Procedure
4629 and then Null_Present (Specification (N)))
4631 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4633 -- Specialize error message based on procedures vs. functions,
4634 -- since functions can't be null subprograms.
4636 if Ekind (Designator) = E_Procedure then
4638 ("interface procedure % must be abstract or null", N);
4641 ("interface function % must be abstract", N);
4647 -- What is the following code for, it used to be
4649 -- ??? Set_Suppress_Elaboration_Checks
4650 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4652 -- The following seems equivalent, but a bit dubious
4654 if Elaboration_Checks_Suppressed (Designator) then
4655 Set_Kill_Elaboration_Checks (Designator);
4658 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4659 Set_Categorization_From_Scope (Designator, Scop);
4662 -- For a compilation unit, check for library-unit pragmas
4664 Push_Scope (Designator);
4665 Set_Categorization_From_Pragmas (N);
4666 Validate_Categorization_Dependency (N, Designator);
4670 -- For a compilation unit, set body required. This flag will only be
4671 -- reset if a valid Import or Interface pragma is processed later on.
4673 if Nkind (Parent (N)) = N_Compilation_Unit then
4674 Set_Body_Required (Parent (N), True);
4676 if Ada_Version >= Ada_2005
4677 and then Nkind (Specification (N)) = N_Procedure_Specification
4678 and then Null_Present (Specification (N))
4681 ("null procedure cannot be declared at library level", N);
4685 Generate_Reference_To_Formals (Designator);
4686 Check_Eliminated (Designator);
4688 if Debug_Flag_C then
4690 Write_Str ("<== subprogram spec ");
4691 Write_Name (Chars (Designator));
4692 Write_Str (" from ");
4693 Write_Location (Sloc (N));
4697 if Is_Protected_Type (Current_Scope) then
4699 -- Indicate that this is a protected operation, because it may be
4700 -- used in subsequent declarations within the protected type.
4702 Set_Convention (Designator, Convention_Protected);
4705 List_Inherited_Pre_Post_Aspects (Designator);
4707 if Has_Aspects (N) then
4708 Analyze_Aspect_Specifications (N, Designator);
4710 end Analyze_Subprogram_Declaration;
4712 --------------------------------------
4713 -- Analyze_Subprogram_Specification --
4714 --------------------------------------
4716 -- Reminder: N here really is a subprogram specification (not a subprogram
4717 -- declaration). This procedure is called to analyze the specification in
4718 -- both subprogram bodies and subprogram declarations (specs).
4720 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4721 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4722 -- Determine whether entity E denotes the spec or body of an invariant
4725 ------------------------------------
4726 -- Is_Invariant_Procedure_Or_Body --
4727 ------------------------------------
4729 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4730 Decl : constant Node_Id := Unit_Declaration_Node (E);
4734 if Nkind (Decl) = N_Subprogram_Body then
4735 Spec := Corresponding_Spec (Decl);
4742 and then Ekind (Spec) = E_Procedure
4743 and then (Is_Partial_Invariant_Procedure (Spec)
4744 or else Is_Invariant_Procedure (Spec));
4745 end Is_Invariant_Procedure_Or_Body;
4749 Designator : constant Entity_Id := Defining_Entity (N);
4750 Formals : constant List_Id := Parameter_Specifications (N);
4752 -- Start of processing for Analyze_Subprogram_Specification
4755 -- User-defined operator is not allowed in SPARK, except as a renaming
4757 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4758 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4760 Check_SPARK_05_Restriction
4761 ("user-defined operator is not allowed", N);
4764 -- Proceed with analysis. Do not emit a cross-reference entry if the
4765 -- specification comes from an expression function, because it may be
4766 -- the completion of a previous declaration. It is not, the cross-
4767 -- reference entry will be emitted for the new subprogram declaration.
4769 if Nkind (Parent (N)) /= N_Expression_Function then
4770 Generate_Definition (Designator);
4773 if Nkind (N) = N_Function_Specification then
4774 Set_Ekind (Designator, E_Function);
4775 Set_Mechanism (Designator, Default_Mechanism);
4777 Set_Ekind (Designator, E_Procedure);
4778 Set_Etype (Designator, Standard_Void_Type);
4781 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4782 -- those subprograms which could be inlined in GNATprove mode (because
4783 -- Body_To_Inline is non-Empty) but should not be inlined.
4785 if GNATprove_Mode then
4786 Set_Is_Inlined_Always (Designator);
4789 -- Introduce new scope for analysis of the formals and the return type
4791 Set_Scope (Designator, Current_Scope);
4793 if Present (Formals) then
4794 Push_Scope (Designator);
4795 Process_Formals (Formals, N);
4797 -- Check dimensions in N for formals with default expression
4799 Analyze_Dimension_Formals (N, Formals);
4801 -- Ada 2005 (AI-345): If this is an overriding operation of an
4802 -- inherited interface operation, and the controlling type is
4803 -- a synchronized type, replace the type with its corresponding
4804 -- record, to match the proper signature of an overriding operation.
4805 -- Same processing for an access parameter whose designated type is
4806 -- derived from a synchronized interface.
4808 -- This modification is not done for invariant procedures because
4809 -- the corresponding record may not necessarely be visible when the
4810 -- concurrent type acts as the full view of a private type.
4813 -- type Prot is private with Type_Invariant => ...;
4814 -- procedure ConcInvariant (Obj : Prot);
4816 -- protected type Prot is ...;
4817 -- type Concurrent_Record_Prot is record ...;
4818 -- procedure ConcInvariant (Obj : Prot) is
4820 -- end ConcInvariant;
4823 -- In the example above, both the spec and body of the invariant
4824 -- procedure must utilize the private type as the controlling type.
4826 if Ada_Version >= Ada_2005
4827 and then not Is_Invariant_Procedure_Or_Body (Designator)
4831 Formal_Typ : Entity_Id;
4832 Rec_Typ : Entity_Id;
4833 Desig_Typ : Entity_Id;
4836 Formal := First_Formal (Designator);
4837 while Present (Formal) loop
4838 Formal_Typ := Etype (Formal);
4840 if Is_Concurrent_Type (Formal_Typ)
4841 and then Present (Corresponding_Record_Type (Formal_Typ))
4843 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4845 if Present (Interfaces (Rec_Typ)) then
4846 Set_Etype (Formal, Rec_Typ);
4849 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4850 Desig_Typ := Designated_Type (Formal_Typ);
4852 if Is_Concurrent_Type (Desig_Typ)
4853 and then Present (Corresponding_Record_Type (Desig_Typ))
4855 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4857 if Present (Interfaces (Rec_Typ)) then
4858 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
4863 Next_Formal (Formal);
4870 -- The subprogram scope is pushed and popped around the processing of
4871 -- the return type for consistency with call above to Process_Formals
4872 -- (which itself can call Analyze_Return_Type), and to ensure that any
4873 -- itype created for the return type will be associated with the proper
4876 elsif Nkind (N) = N_Function_Specification then
4877 Push_Scope (Designator);
4878 Analyze_Return_Type (N);
4884 if Nkind (N) = N_Function_Specification then
4886 -- Deal with operator symbol case
4888 if Nkind (Designator) = N_Defining_Operator_Symbol then
4889 Valid_Operator_Definition (Designator);
4892 May_Need_Actuals (Designator);
4894 -- Ada 2005 (AI-251): If the return type is abstract, verify that
4895 -- the subprogram is abstract also. This does not apply to renaming
4896 -- declarations, where abstractness is inherited, and to subprogram
4897 -- bodies generated for stream operations, which become renamings as
4900 -- In case of primitives associated with abstract interface types
4901 -- the check is applied later (see Analyze_Subprogram_Declaration).
4903 if not Nkind_In (Original_Node (Parent (N)),
4904 N_Abstract_Subprogram_Declaration,
4905 N_Formal_Abstract_Subprogram_Declaration,
4906 N_Subprogram_Renaming_Declaration)
4908 if Is_Abstract_Type (Etype (Designator))
4909 and then not Is_Interface (Etype (Designator))
4912 ("function that returns abstract type must be abstract", N);
4914 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
4915 -- access result whose designated type is abstract.
4917 elsif Ada_Version >= Ada_2012
4918 and then Nkind (Result_Definition (N)) = N_Access_Definition
4920 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
4921 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
4924 ("function whose access result designates abstract type "
4925 & "must be abstract", N);
4931 end Analyze_Subprogram_Specification;
4933 -----------------------
4934 -- Check_Conformance --
4935 -----------------------
4937 procedure Check_Conformance
4938 (New_Id : Entity_Id;
4940 Ctype : Conformance_Type;
4942 Conforms : out Boolean;
4943 Err_Loc : Node_Id := Empty;
4944 Get_Inst : Boolean := False;
4945 Skip_Controlling_Formals : Boolean := False)
4947 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
4948 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
4949 -- If Errmsg is True, then processing continues to post an error message
4950 -- for conformance error on given node. Two messages are output. The
4951 -- first message points to the previous declaration with a general "no
4952 -- conformance" message. The second is the detailed reason, supplied as
4953 -- Msg. The parameter N provide information for a possible & insertion
4954 -- in the message, and also provides the location for posting the
4955 -- message in the absence of a specified Err_Loc location.
4957 function Conventions_Match
4959 Id2 : Entity_Id) return Boolean;
4960 -- Determine whether the conventions of arbitrary entities Id1 and Id2
4963 -----------------------
4964 -- Conformance_Error --
4965 -----------------------
4967 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
4974 if No (Err_Loc) then
4980 Error_Msg_Sloc := Sloc (Old_Id);
4983 when Type_Conformant =>
4984 Error_Msg_N -- CODEFIX
4985 ("not type conformant with declaration#!", Enode);
4987 when Mode_Conformant =>
4988 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
4990 ("not mode conformant with operation inherited#!",
4994 ("not mode conformant with declaration#!", Enode);
4997 when Subtype_Conformant =>
4998 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5000 ("not subtype conformant with operation inherited#!",
5004 ("not subtype conformant with declaration#!", Enode);
5007 when Fully_Conformant =>
5008 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5009 Error_Msg_N -- CODEFIX
5010 ("not fully conformant with operation inherited#!",
5013 Error_Msg_N -- CODEFIX
5014 ("not fully conformant with declaration#!", Enode);
5018 Error_Msg_NE (Msg, Enode, N);
5020 end Conformance_Error;
5022 -----------------------
5023 -- Conventions_Match --
5024 -----------------------
5026 function Conventions_Match
5028 Id2 : Entity_Id) return Boolean
5031 -- Ignore the conventions of anonymous access-to-subprogram types
5032 -- and subprogram types because these are internally generated and
5033 -- the only way these may receive a convention is if they inherit
5034 -- the convention of a related subprogram.
5036 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5039 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5044 -- Otherwise compare the conventions directly
5047 return Convention (Id1) = Convention (Id2);
5049 end Conventions_Match;
5053 Old_Type : constant Entity_Id := Etype (Old_Id);
5054 New_Type : constant Entity_Id := Etype (New_Id);
5055 Old_Formal : Entity_Id;
5056 New_Formal : Entity_Id;
5057 Access_Types_Match : Boolean;
5058 Old_Formal_Base : Entity_Id;
5059 New_Formal_Base : Entity_Id;
5061 -- Start of processing for Check_Conformance
5066 -- We need a special case for operators, since they don't appear
5069 if Ctype = Type_Conformant then
5070 if Ekind (New_Id) = E_Operator
5071 and then Operator_Matches_Spec (New_Id, Old_Id)
5077 -- If both are functions/operators, check return types conform
5079 if Old_Type /= Standard_Void_Type
5081 New_Type /= Standard_Void_Type
5083 -- If we are checking interface conformance we omit controlling
5084 -- arguments and result, because we are only checking the conformance
5085 -- of the remaining parameters.
5087 if Has_Controlling_Result (Old_Id)
5088 and then Has_Controlling_Result (New_Id)
5089 and then Skip_Controlling_Formals
5093 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5094 if Ctype >= Subtype_Conformant
5095 and then not Predicates_Match (Old_Type, New_Type)
5098 ("\predicate of return type does not match!", New_Id);
5101 ("\return type does not match!", New_Id);
5107 -- Ada 2005 (AI-231): In case of anonymous access types check the
5108 -- null-exclusion and access-to-constant attributes match.
5110 if Ada_Version >= Ada_2005
5111 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5113 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5114 or else Is_Access_Constant (Etype (Old_Type)) /=
5115 Is_Access_Constant (Etype (New_Type)))
5117 Conformance_Error ("\return type does not match!", New_Id);
5121 -- If either is a function/operator and the other isn't, error
5123 elsif Old_Type /= Standard_Void_Type
5124 or else New_Type /= Standard_Void_Type
5126 Conformance_Error ("\functions can only match functions!", New_Id);
5130 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5131 -- If this is a renaming as body, refine error message to indicate that
5132 -- the conflict is with the original declaration. If the entity is not
5133 -- frozen, the conventions don't have to match, the one of the renamed
5134 -- entity is inherited.
5136 if Ctype >= Subtype_Conformant then
5137 if not Conventions_Match (Old_Id, New_Id) then
5138 if not Is_Frozen (New_Id) then
5141 elsif Present (Err_Loc)
5142 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5143 and then Present (Corresponding_Spec (Err_Loc))
5145 Error_Msg_Name_1 := Chars (New_Id);
5147 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5148 Conformance_Error ("\prior declaration for% has convention %!");
5151 Conformance_Error ("\calling conventions do not match!");
5156 elsif Is_Formal_Subprogram (Old_Id)
5157 or else Is_Formal_Subprogram (New_Id)
5159 Conformance_Error ("\formal subprograms not allowed!");
5164 -- Deal with parameters
5166 -- Note: we use the entity information, rather than going directly
5167 -- to the specification in the tree. This is not only simpler, but
5168 -- absolutely necessary for some cases of conformance tests between
5169 -- operators, where the declaration tree simply does not exist.
5171 Old_Formal := First_Formal (Old_Id);
5172 New_Formal := First_Formal (New_Id);
5173 while Present (Old_Formal) and then Present (New_Formal) loop
5174 if Is_Controlling_Formal (Old_Formal)
5175 and then Is_Controlling_Formal (New_Formal)
5176 and then Skip_Controlling_Formals
5178 -- The controlling formals will have different types when
5179 -- comparing an interface operation with its match, but both
5180 -- or neither must be access parameters.
5182 if Is_Access_Type (Etype (Old_Formal))
5184 Is_Access_Type (Etype (New_Formal))
5186 goto Skip_Controlling_Formal;
5189 ("\access parameter does not match!", New_Formal);
5193 -- Ada 2012: Mode conformance also requires that formal parameters
5194 -- be both aliased, or neither.
5196 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5197 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5199 ("\aliased parameter mismatch!", New_Formal);
5203 if Ctype = Fully_Conformant then
5205 -- Names must match. Error message is more accurate if we do
5206 -- this before checking that the types of the formals match.
5208 if Chars (Old_Formal) /= Chars (New_Formal) then
5209 Conformance_Error ("\name& does not match!", New_Formal);
5211 -- Set error posted flag on new formal as well to stop
5212 -- junk cascaded messages in some cases.
5214 Set_Error_Posted (New_Formal);
5218 -- Null exclusion must match
5220 if Null_Exclusion_Present (Parent (Old_Formal))
5222 Null_Exclusion_Present (Parent (New_Formal))
5224 -- Only give error if both come from source. This should be
5225 -- investigated some time, since it should not be needed ???
5227 if Comes_From_Source (Old_Formal)
5229 Comes_From_Source (New_Formal)
5232 ("\null exclusion for& does not match", New_Formal);
5234 -- Mark error posted on the new formal to avoid duplicated
5235 -- complaint about types not matching.
5237 Set_Error_Posted (New_Formal);
5242 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5243 -- case occurs whenever a subprogram is being renamed and one of its
5244 -- parameters imposes a null exclusion. For example:
5246 -- type T is null record;
5247 -- type Acc_T is access T;
5248 -- subtype Acc_T_Sub is Acc_T;
5250 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5251 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5254 Old_Formal_Base := Etype (Old_Formal);
5255 New_Formal_Base := Etype (New_Formal);
5258 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5259 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5262 Access_Types_Match := Ada_Version >= Ada_2005
5264 -- Ensure that this rule is only applied when New_Id is a
5265 -- renaming of Old_Id.
5267 and then Nkind (Parent (Parent (New_Id))) =
5268 N_Subprogram_Renaming_Declaration
5269 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5270 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5271 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5273 -- Now handle the allowed access-type case
5275 and then Is_Access_Type (Old_Formal_Base)
5276 and then Is_Access_Type (New_Formal_Base)
5278 -- The type kinds must match. The only exception occurs with
5279 -- multiple generics of the form:
5282 -- type F is private; type A is private;
5283 -- type F_Ptr is access F; type A_Ptr is access A;
5284 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5285 -- package F_Pack is ... package A_Pack is
5286 -- package F_Inst is
5287 -- new F_Pack (A, A_Ptr, A_P);
5289 -- When checking for conformance between the parameters of A_P
5290 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5291 -- because the compiler has transformed A_Ptr into a subtype of
5292 -- F_Ptr. We catch this case in the code below.
5294 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5296 (Is_Generic_Type (Old_Formal_Base)
5297 and then Is_Generic_Type (New_Formal_Base)
5298 and then Is_Internal (New_Formal_Base)
5299 and then Etype (Etype (New_Formal_Base)) =
5301 and then Directly_Designated_Type (Old_Formal_Base) =
5302 Directly_Designated_Type (New_Formal_Base)
5303 and then ((Is_Itype (Old_Formal_Base)
5304 and then Can_Never_Be_Null (Old_Formal_Base))
5306 (Is_Itype (New_Formal_Base)
5307 and then Can_Never_Be_Null (New_Formal_Base)));
5309 -- Types must always match. In the visible part of an instance,
5310 -- usual overloading rules for dispatching operations apply, and
5311 -- we check base types (not the actual subtypes).
5313 if In_Instance_Visible_Part
5314 and then Is_Dispatching_Operation (New_Id)
5316 if not Conforming_Types
5317 (T1 => Base_Type (Etype (Old_Formal)),
5318 T2 => Base_Type (Etype (New_Formal)),
5320 Get_Inst => Get_Inst)
5321 and then not Access_Types_Match
5323 Conformance_Error ("\type of & does not match!", New_Formal);
5327 elsif not Conforming_Types
5328 (T1 => Old_Formal_Base,
5329 T2 => New_Formal_Base,
5331 Get_Inst => Get_Inst)
5332 and then not Access_Types_Match
5334 -- Don't give error message if old type is Any_Type. This test
5335 -- avoids some cascaded errors, e.g. in case of a bad spec.
5337 if Errmsg and then Old_Formal_Base = Any_Type then
5340 if Ctype >= Subtype_Conformant
5342 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5345 ("\predicate of & does not match!", New_Formal);
5348 ("\type of & does not match!", New_Formal);
5350 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5352 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5360 -- For mode conformance, mode must match
5362 if Ctype >= Mode_Conformant then
5363 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5364 if not Ekind_In (New_Id, E_Function, E_Procedure)
5365 or else not Is_Primitive_Wrapper (New_Id)
5367 Conformance_Error ("\mode of & does not match!", New_Formal);
5371 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5373 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5375 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5378 ("\mode of & does not match!", New_Formal);
5385 -- Part of mode conformance for access types is having the same
5386 -- constant modifier.
5388 elsif Access_Types_Match
5389 and then Is_Access_Constant (Old_Formal_Base) /=
5390 Is_Access_Constant (New_Formal_Base)
5393 ("\constant modifier does not match!", New_Formal);
5398 if Ctype >= Subtype_Conformant then
5400 -- Ada 2005 (AI-231): In case of anonymous access types check
5401 -- the null-exclusion and access-to-constant attributes must
5402 -- match. For null exclusion, we test the types rather than the
5403 -- formals themselves, since the attribute is only set reliably
5404 -- on the formals in the Ada 95 case, and we exclude the case
5405 -- where Old_Formal is marked as controlling, to avoid errors
5406 -- when matching completing bodies with dispatching declarations
5407 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5409 if Ada_Version >= Ada_2005
5410 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5411 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5413 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5414 Can_Never_Be_Null (Etype (New_Formal))
5416 not Is_Controlling_Formal (Old_Formal))
5418 Is_Access_Constant (Etype (Old_Formal)) /=
5419 Is_Access_Constant (Etype (New_Formal)))
5421 -- Do not complain if error already posted on New_Formal. This
5422 -- avoids some redundant error messages.
5424 and then not Error_Posted (New_Formal)
5426 -- It is allowed to omit the null-exclusion in case of stream
5427 -- attribute subprograms. We recognize stream subprograms
5428 -- through their TSS-generated suffix.
5431 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5434 if TSS_Name /= TSS_Stream_Read
5435 and then TSS_Name /= TSS_Stream_Write
5436 and then TSS_Name /= TSS_Stream_Input
5437 and then TSS_Name /= TSS_Stream_Output
5439 -- Here we have a definite conformance error. It is worth
5440 -- special casing the error message for the case of a
5441 -- controlling formal (which excludes null).
5443 if Is_Controlling_Formal (New_Formal) then
5444 Error_Msg_Node_2 := Scope (New_Formal);
5446 ("\controlling formal & of & excludes null, "
5447 & "declaration must exclude null as well",
5450 -- Normal case (couldn't we give more detail here???)
5454 ("\type of & does not match!", New_Formal);
5463 -- Full conformance checks
5465 if Ctype = Fully_Conformant then
5467 -- We have checked already that names match
5469 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5471 -- Check default expressions for in parameters
5474 NewD : constant Boolean :=
5475 Present (Default_Value (New_Formal));
5476 OldD : constant Boolean :=
5477 Present (Default_Value (Old_Formal));
5479 if NewD or OldD then
5481 -- The old default value has been analyzed because the
5482 -- current full declaration will have frozen everything
5483 -- before. The new default value has not been analyzed,
5484 -- so analyze it now before we check for conformance.
5487 Push_Scope (New_Id);
5488 Preanalyze_Spec_Expression
5489 (Default_Value (New_Formal), Etype (New_Formal));
5493 if not (NewD and OldD)
5494 or else not Fully_Conformant_Expressions
5495 (Default_Value (Old_Formal),
5496 Default_Value (New_Formal))
5499 ("\default expression for & does not match!",
5508 -- A couple of special checks for Ada 83 mode. These checks are
5509 -- skipped if either entity is an operator in package Standard,
5510 -- or if either old or new instance is not from the source program.
5512 if Ada_Version = Ada_83
5513 and then Sloc (Old_Id) > Standard_Location
5514 and then Sloc (New_Id) > Standard_Location
5515 and then Comes_From_Source (Old_Id)
5516 and then Comes_From_Source (New_Id)
5519 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5520 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5523 -- Explicit IN must be present or absent in both cases. This
5524 -- test is required only in the full conformance case.
5526 if In_Present (Old_Param) /= In_Present (New_Param)
5527 and then Ctype = Fully_Conformant
5530 ("\(Ada 83) IN must appear in both declarations",
5535 -- Grouping (use of comma in param lists) must be the same
5536 -- This is where we catch a misconformance like:
5539 -- A : Integer; B : Integer
5541 -- which are represented identically in the tree except
5542 -- for the setting of the flags More_Ids and Prev_Ids.
5544 if More_Ids (Old_Param) /= More_Ids (New_Param)
5545 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5548 ("\grouping of & does not match!", New_Formal);
5554 -- This label is required when skipping controlling formals
5556 <<Skip_Controlling_Formal>>
5558 Next_Formal (Old_Formal);
5559 Next_Formal (New_Formal);
5562 if Present (Old_Formal) then
5563 Conformance_Error ("\too few parameters!");
5566 elsif Present (New_Formal) then
5567 Conformance_Error ("\too many parameters!", New_Formal);
5570 end Check_Conformance;
5572 -----------------------
5573 -- Check_Conventions --
5574 -----------------------
5576 procedure Check_Conventions (Typ : Entity_Id) is
5577 Ifaces_List : Elist_Id;
5579 procedure Check_Convention (Op : Entity_Id);
5580 -- Verify that the convention of inherited dispatching operation Op is
5581 -- consistent among all subprograms it overrides. In order to minimize
5582 -- the search, Search_From is utilized to designate a specific point in
5583 -- the list rather than iterating over the whole list once more.
5585 ----------------------
5586 -- Check_Convention --
5587 ----------------------
5589 procedure Check_Convention (Op : Entity_Id) is
5590 Op_Conv : constant Convention_Id := Convention (Op);
5591 Iface_Conv : Convention_Id;
5592 Iface_Elmt : Elmt_Id;
5593 Iface_Prim_Elmt : Elmt_Id;
5594 Iface_Prim : Entity_Id;
5597 Iface_Elmt := First_Elmt (Ifaces_List);
5598 while Present (Iface_Elmt) loop
5600 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5601 while Present (Iface_Prim_Elmt) loop
5602 Iface_Prim := Node (Iface_Prim_Elmt);
5603 Iface_Conv := Convention (Iface_Prim);
5605 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5606 and then Iface_Conv /= Op_Conv
5609 ("inconsistent conventions in primitive operations", Typ);
5611 Error_Msg_Name_1 := Chars (Op);
5612 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5613 Error_Msg_Sloc := Sloc (Op);
5615 if Comes_From_Source (Op) or else No (Alias (Op)) then
5616 if not Present (Overridden_Operation (Op)) then
5617 Error_Msg_N ("\\primitive % defined #", Typ);
5620 ("\\overriding operation % with "
5621 & "convention % defined #", Typ);
5624 else pragma Assert (Present (Alias (Op)));
5625 Error_Msg_Sloc := Sloc (Alias (Op));
5626 Error_Msg_N ("\\inherited operation % with "
5627 & "convention % defined #", Typ);
5630 Error_Msg_Name_1 := Chars (Op);
5631 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5632 Error_Msg_Sloc := Sloc (Iface_Prim);
5633 Error_Msg_N ("\\overridden operation % with "
5634 & "convention % defined #", Typ);
5636 -- Avoid cascading errors
5641 Next_Elmt (Iface_Prim_Elmt);
5644 Next_Elmt (Iface_Elmt);
5646 end Check_Convention;
5650 Prim_Op : Entity_Id;
5651 Prim_Op_Elmt : Elmt_Id;
5653 -- Start of processing for Check_Conventions
5656 if not Has_Interfaces (Typ) then
5660 Collect_Interfaces (Typ, Ifaces_List);
5662 -- The algorithm checks every overriding dispatching operation against
5663 -- all the corresponding overridden dispatching operations, detecting
5664 -- differences in conventions.
5666 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5667 while Present (Prim_Op_Elmt) loop
5668 Prim_Op := Node (Prim_Op_Elmt);
5670 -- A small optimization: skip the predefined dispatching operations
5671 -- since they always have the same convention.
5673 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5674 Check_Convention (Prim_Op);
5677 Next_Elmt (Prim_Op_Elmt);
5679 end Check_Conventions;
5681 ------------------------------
5682 -- Check_Delayed_Subprogram --
5683 ------------------------------
5685 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5688 procedure Possible_Freeze (T : Entity_Id);
5689 -- T is the type of either a formal parameter or of the return type.
5690 -- If T is not yet frozen and needs a delayed freeze, then the
5691 -- subprogram itself must be delayed.
5693 ---------------------
5694 -- Possible_Freeze --
5695 ---------------------
5697 procedure Possible_Freeze (T : Entity_Id) is
5699 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5700 Set_Has_Delayed_Freeze (Designator);
5702 elsif Is_Access_Type (T)
5703 and then Has_Delayed_Freeze (Designated_Type (T))
5704 and then not Is_Frozen (Designated_Type (T))
5706 Set_Has_Delayed_Freeze (Designator);
5709 end Possible_Freeze;
5711 -- Start of processing for Check_Delayed_Subprogram
5714 -- All subprograms, including abstract subprograms, may need a freeze
5715 -- node if some formal type or the return type needs one.
5717 Possible_Freeze (Etype (Designator));
5718 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5720 -- Need delayed freeze if any of the formal types themselves need
5721 -- a delayed freeze and are not yet frozen.
5723 F := First_Formal (Designator);
5724 while Present (F) loop
5725 Possible_Freeze (Etype (F));
5726 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5730 -- Mark functions that return by reference. Note that it cannot be
5731 -- done for delayed_freeze subprograms because the underlying
5732 -- returned type may not be known yet (for private types)
5734 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5736 Typ : constant Entity_Id := Etype (Designator);
5737 Utyp : constant Entity_Id := Underlying_Type (Typ);
5739 if Is_Limited_View (Typ) then
5740 Set_Returns_By_Ref (Designator);
5741 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5742 Set_Returns_By_Ref (Designator);
5746 end Check_Delayed_Subprogram;
5748 ------------------------------------
5749 -- Check_Discriminant_Conformance --
5750 ------------------------------------
5752 procedure Check_Discriminant_Conformance
5757 Old_Discr : Entity_Id := First_Discriminant (Prev);
5758 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5759 New_Discr_Id : Entity_Id;
5760 New_Discr_Type : Entity_Id;
5762 procedure Conformance_Error (Msg : String; N : Node_Id);
5763 -- Post error message for conformance error on given node. Two messages
5764 -- are output. The first points to the previous declaration with a
5765 -- general "no conformance" message. The second is the detailed reason,
5766 -- supplied as Msg. The parameter N provide information for a possible
5767 -- & insertion in the message.
5769 -----------------------
5770 -- Conformance_Error --
5771 -----------------------
5773 procedure Conformance_Error (Msg : String; N : Node_Id) is
5775 Error_Msg_Sloc := Sloc (Prev_Loc);
5776 Error_Msg_N -- CODEFIX
5777 ("not fully conformant with declaration#!", N);
5778 Error_Msg_NE (Msg, N, N);
5779 end Conformance_Error;
5781 -- Start of processing for Check_Discriminant_Conformance
5784 while Present (Old_Discr) and then Present (New_Discr) loop
5785 New_Discr_Id := Defining_Identifier (New_Discr);
5787 -- The subtype mark of the discriminant on the full type has not
5788 -- been analyzed so we do it here. For an access discriminant a new
5791 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5793 Access_Definition (N, Discriminant_Type (New_Discr));
5796 Analyze (Discriminant_Type (New_Discr));
5797 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5799 -- Ada 2005: if the discriminant definition carries a null
5800 -- exclusion, create an itype to check properly for consistency
5801 -- with partial declaration.
5803 if Is_Access_Type (New_Discr_Type)
5804 and then Null_Exclusion_Present (New_Discr)
5807 Create_Null_Excluding_Itype
5808 (T => New_Discr_Type,
5809 Related_Nod => New_Discr,
5810 Scope_Id => Current_Scope);
5814 if not Conforming_Types
5815 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5817 Conformance_Error ("type of & does not match!", New_Discr_Id);
5820 -- Treat the new discriminant as an occurrence of the old one,
5821 -- for navigation purposes, and fill in some semantic
5822 -- information, for completeness.
5824 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5825 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5826 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5831 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5832 Conformance_Error ("name & does not match!", New_Discr_Id);
5836 -- Default expressions must match
5839 NewD : constant Boolean :=
5840 Present (Expression (New_Discr));
5841 OldD : constant Boolean :=
5842 Present (Expression (Parent (Old_Discr)));
5845 if NewD or OldD then
5847 -- The old default value has been analyzed and expanded,
5848 -- because the current full declaration will have frozen
5849 -- everything before. The new default values have not been
5850 -- expanded, so expand now to check conformance.
5853 Preanalyze_Spec_Expression
5854 (Expression (New_Discr), New_Discr_Type);
5857 if not (NewD and OldD)
5858 or else not Fully_Conformant_Expressions
5859 (Expression (Parent (Old_Discr)),
5860 Expression (New_Discr))
5864 ("default expression for & does not match!",
5871 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
5873 if Ada_Version = Ada_83 then
5875 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
5878 -- Grouping (use of comma in param lists) must be the same
5879 -- This is where we catch a misconformance like:
5882 -- A : Integer; B : Integer
5884 -- which are represented identically in the tree except
5885 -- for the setting of the flags More_Ids and Prev_Ids.
5887 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
5888 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
5891 ("grouping of & does not match!", New_Discr_Id);
5897 Next_Discriminant (Old_Discr);
5901 if Present (Old_Discr) then
5902 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
5905 elsif Present (New_Discr) then
5907 ("too many discriminants!", Defining_Identifier (New_Discr));
5910 end Check_Discriminant_Conformance;
5912 ----------------------------
5913 -- Check_Fully_Conformant --
5914 ----------------------------
5916 procedure Check_Fully_Conformant
5917 (New_Id : Entity_Id;
5919 Err_Loc : Node_Id := Empty)
5922 pragma Warnings (Off, Result);
5925 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
5926 end Check_Fully_Conformant;
5928 --------------------------
5929 -- Check_Limited_Return --
5930 --------------------------
5932 procedure Check_Limited_Return
5938 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
5939 -- replaced by anonymous access results. This is an incompatibility with
5940 -- Ada 95. Not clear whether this should be enforced yet or perhaps
5941 -- controllable with special switch. ???
5943 -- A limited interface that is not immutably limited is OK
5945 if Is_Limited_Interface (R_Type)
5947 not (Is_Task_Interface (R_Type)
5948 or else Is_Protected_Interface (R_Type)
5949 or else Is_Synchronized_Interface (R_Type))
5953 elsif Is_Limited_Type (R_Type)
5954 and then not Is_Interface (R_Type)
5955 and then Comes_From_Source (N)
5956 and then not In_Instance_Body
5957 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
5959 -- Error in Ada 2005
5961 if Ada_Version >= Ada_2005
5962 and then not Debug_Flag_Dot_L
5963 and then not GNAT_Mode
5966 ("(Ada 2005) cannot copy object of a limited type "
5967 & "(RM-2005 6.5(5.5/2))", Expr);
5969 if Is_Limited_View (R_Type) then
5971 ("\return by reference not permitted in Ada 2005", Expr);
5974 -- Warn in Ada 95 mode, to give folks a heads up about this
5977 -- In GNAT mode, this is just a warning, to allow it to be evilly
5978 -- turned off. Otherwise it is a real error.
5980 -- In a generic context, simplify the warning because it makes no
5981 -- sense to discuss pass-by-reference or copy.
5983 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
5984 if Inside_A_Generic then
5986 ("return of limited object not permitted in Ada 2005 "
5987 & "(RM-2005 6.5(5.5/2))?y?", Expr);
5989 elsif Is_Limited_View (R_Type) then
5991 ("return by reference not permitted in Ada 2005 "
5992 & "(RM-2005 6.5(5.5/2))?y?", Expr);
5995 ("cannot copy object of a limited type in Ada 2005 "
5996 & "(RM-2005 6.5(5.5/2))?y?", Expr);
5999 -- Ada 95 mode, and compatibility warnings disabled
6002 pragma Assert (Ada_Version <= Ada_95);
6003 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6004 return; -- skip continuation messages below
6007 if not Inside_A_Generic then
6009 ("\consider switching to return of access type", Expr);
6010 Explain_Limited_Type (R_Type, Expr);
6013 end Check_Limited_Return;
6015 ---------------------------
6016 -- Check_Mode_Conformant --
6017 ---------------------------
6019 procedure Check_Mode_Conformant
6020 (New_Id : Entity_Id;
6022 Err_Loc : Node_Id := Empty;
6023 Get_Inst : Boolean := False)
6026 pragma Warnings (Off, Result);
6029 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6030 end Check_Mode_Conformant;
6032 --------------------------------
6033 -- Check_Overriding_Indicator --
6034 --------------------------------
6036 procedure Check_Overriding_Indicator
6038 Overridden_Subp : Entity_Id;
6039 Is_Primitive : Boolean)
6045 -- No overriding indicator for literals
6047 if Ekind (Subp) = E_Enumeration_Literal then
6050 elsif Ekind (Subp) = E_Entry then
6051 Decl := Parent (Subp);
6053 -- No point in analyzing a malformed operator
6055 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6056 and then Error_Posted (Subp)
6061 Decl := Unit_Declaration_Node (Subp);
6064 if Nkind_In (Decl, N_Subprogram_Body,
6065 N_Subprogram_Body_Stub,
6066 N_Subprogram_Declaration,
6067 N_Abstract_Subprogram_Declaration,
6068 N_Subprogram_Renaming_Declaration)
6070 Spec := Specification (Decl);
6072 elsif Nkind (Decl) = N_Entry_Declaration then
6079 -- The overriding operation is type conformant with the overridden one,
6080 -- but the names of the formals are not required to match. If the names
6081 -- appear permuted in the overriding operation, this is a possible
6082 -- source of confusion that is worth diagnosing. Controlling formals
6083 -- often carry names that reflect the type, and it is not worthwhile
6084 -- requiring that their names match.
6086 if Present (Overridden_Subp)
6087 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6094 Form1 := First_Formal (Subp);
6095 Form2 := First_Formal (Overridden_Subp);
6097 -- If the overriding operation is a synchronized operation, skip
6098 -- the first parameter of the overridden operation, which is
6099 -- implicit in the new one. If the operation is declared in the
6100 -- body it is not primitive and all formals must match.
6102 if Is_Concurrent_Type (Scope (Subp))
6103 and then Is_Tagged_Type (Scope (Subp))
6104 and then not Has_Completion (Scope (Subp))
6106 Form2 := Next_Formal (Form2);
6109 if Present (Form1) then
6110 Form1 := Next_Formal (Form1);
6111 Form2 := Next_Formal (Form2);
6114 while Present (Form1) loop
6115 if not Is_Controlling_Formal (Form1)
6116 and then Present (Next_Formal (Form2))
6117 and then Chars (Form1) = Chars (Next_Formal (Form2))
6119 Error_Msg_Node_2 := Alias (Overridden_Subp);
6120 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6122 ("& does not match corresponding formal of&#",
6127 Next_Formal (Form1);
6128 Next_Formal (Form2);
6133 -- If there is an overridden subprogram, then check that there is no
6134 -- "not overriding" indicator, and mark the subprogram as overriding.
6135 -- This is not done if the overridden subprogram is marked as hidden,
6136 -- which can occur for the case of inherited controlled operations
6137 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6138 -- subprogram is not itself hidden. (Note: This condition could probably
6139 -- be simplified, leaving out the testing for the specific controlled
6140 -- cases, but it seems safer and clearer this way, and echoes similar
6141 -- special-case tests of this kind in other places.)
6143 if Present (Overridden_Subp)
6144 and then (not Is_Hidden (Overridden_Subp)
6146 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6149 and then Present (Alias (Overridden_Subp))
6150 and then not Is_Hidden (Alias (Overridden_Subp))))
6152 if Must_Not_Override (Spec) then
6153 Error_Msg_Sloc := Sloc (Overridden_Subp);
6155 if Ekind (Subp) = E_Entry then
6157 ("entry & overrides inherited operation #", Spec, Subp);
6160 ("subprogram & overrides inherited operation #", Spec, Subp);
6163 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6164 -- as an extension of Root_Controlled, and thus has a useless Adjust
6165 -- operation. This operation should not be inherited by other limited
6166 -- controlled types. An explicit Adjust for them is not overriding.
6168 elsif Must_Override (Spec)
6169 and then Chars (Overridden_Subp) = Name_Adjust
6170 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6171 and then Present (Alias (Overridden_Subp))
6172 and then In_Predefined_Unit (Alias (Overridden_Subp))
6175 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6176 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6178 elsif Is_Subprogram (Subp) then
6179 if Is_Init_Proc (Subp) then
6182 elsif No (Overridden_Operation (Subp)) then
6184 -- For entities generated by Derive_Subprograms the overridden
6185 -- operation is the inherited primitive (which is available
6186 -- through the attribute alias)
6188 if (Is_Dispatching_Operation (Subp)
6189 or else Is_Dispatching_Operation (Overridden_Subp))
6190 and then not Comes_From_Source (Overridden_Subp)
6191 and then Find_Dispatching_Type (Overridden_Subp) =
6192 Find_Dispatching_Type (Subp)
6193 and then Present (Alias (Overridden_Subp))
6194 and then Comes_From_Source (Alias (Overridden_Subp))
6196 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6197 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6200 Set_Overridden_Operation (Subp, Overridden_Subp);
6201 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6206 -- If primitive flag is set or this is a protected operation, then
6207 -- the operation is overriding at the point of its declaration, so
6208 -- warn if necessary. Otherwise it may have been declared before the
6209 -- operation it overrides and no check is required.
6212 and then not Must_Override (Spec)
6213 and then (Is_Primitive
6214 or else Ekind (Scope (Subp)) = E_Protected_Type)
6216 Style.Missing_Overriding (Decl, Subp);
6219 -- If Subp is an operator, it may override a predefined operation, if
6220 -- it is defined in the same scope as the type to which it applies.
6221 -- In that case Overridden_Subp is empty because of our implicit
6222 -- representation for predefined operators. We have to check whether the
6223 -- signature of Subp matches that of a predefined operator. Note that
6224 -- first argument provides the name of the operator, and the second
6225 -- argument the signature that may match that of a standard operation.
6226 -- If the indicator is overriding, then the operator must match a
6227 -- predefined signature, because we know already that there is no
6228 -- explicit overridden operation.
6230 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6231 if Must_Not_Override (Spec) then
6233 -- If this is not a primitive or a protected subprogram, then
6234 -- "not overriding" is illegal.
6237 and then Ekind (Scope (Subp)) /= E_Protected_Type
6239 Error_Msg_N ("overriding indicator only allowed "
6240 & "if subprogram is primitive", Subp);
6242 elsif Can_Override_Operator (Subp) then
6244 ("subprogram& overrides predefined operator ", Spec, Subp);
6247 elsif Must_Override (Spec) then
6248 if No (Overridden_Operation (Subp))
6249 and then not Can_Override_Operator (Subp)
6251 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6254 elsif not Error_Posted (Subp)
6255 and then Style_Check
6256 and then Can_Override_Operator (Subp)
6257 and then not In_Predefined_Unit (Subp)
6259 -- If style checks are enabled, indicate that the indicator is
6260 -- missing. However, at the point of declaration, the type of
6261 -- which this is a primitive operation may be private, in which
6262 -- case the indicator would be premature.
6264 if Has_Private_Declaration (Etype (Subp))
6265 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6269 Style.Missing_Overriding (Decl, Subp);
6273 elsif Must_Override (Spec) then
6274 if Ekind (Subp) = E_Entry then
6275 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6277 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6280 -- If the operation is marked "not overriding" and it's not primitive
6281 -- then an error is issued, unless this is an operation of a task or
6282 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6283 -- has been specified have already been checked above.
6285 elsif Must_Not_Override (Spec)
6286 and then not Is_Primitive
6287 and then Ekind (Subp) /= E_Entry
6288 and then Ekind (Scope (Subp)) /= E_Protected_Type
6291 ("overriding indicator only allowed if subprogram is primitive",
6295 end Check_Overriding_Indicator;
6301 -- Note: this procedure needs to know far too much about how the expander
6302 -- messes with exceptions. The use of the flag Exception_Junk and the
6303 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6304 -- works, but is not very clean. It would be better if the expansion
6305 -- routines would leave Original_Node working nicely, and we could use
6306 -- Original_Node here to ignore all the peculiar expander messing ???
6308 procedure Check_Returns
6312 Proc : Entity_Id := Empty)
6316 procedure Check_Statement_Sequence (L : List_Id);
6317 -- Internal recursive procedure to check a list of statements for proper
6318 -- termination by a return statement (or a transfer of control or a
6319 -- compound statement that is itself internally properly terminated).
6321 ------------------------------
6322 -- Check_Statement_Sequence --
6323 ------------------------------
6325 procedure Check_Statement_Sequence (L : List_Id) is
6330 function Assert_False return Boolean;
6331 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6332 -- rewritten as a null statement when assertions are off. The assert
6333 -- is not active, but it is still enough to kill the warning.
6339 function Assert_False return Boolean is
6340 Orig : constant Node_Id := Original_Node (Last_Stm);
6343 if Nkind (Orig) = N_Pragma
6344 and then Pragma_Name (Orig) = Name_Assert
6345 and then not Error_Posted (Orig)
6348 Arg : constant Node_Id :=
6349 First (Pragma_Argument_Associations (Orig));
6350 Exp : constant Node_Id := Expression (Arg);
6352 return Nkind (Exp) = N_Identifier
6353 and then Chars (Exp) = Name_False;
6363 Raise_Exception_Call : Boolean;
6364 -- Set True if statement sequence terminated by Raise_Exception call
6365 -- or a Reraise_Occurrence call.
6367 -- Start of processing for Check_Statement_Sequence
6370 Raise_Exception_Call := False;
6372 -- Get last real statement
6374 Last_Stm := Last (L);
6376 -- Deal with digging out exception handler statement sequences that
6377 -- have been transformed by the local raise to goto optimization.
6378 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6379 -- optimization has occurred, we are looking at something like:
6382 -- original stmts in block
6386 -- goto L1; | omitted if No_Exception_Propagation
6391 -- goto L3; -- skip handler when exception not raised
6393 -- <<L1>> -- target label for local exception
6407 -- and what we have to do is to dig out the estmts1 and estmts2
6408 -- sequences (which were the original sequences of statements in
6409 -- the exception handlers) and check them.
6411 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6416 exit when Nkind (Stm) /= N_Block_Statement;
6417 exit when not Exception_Junk (Stm);
6420 exit when Nkind (Stm) /= N_Label;
6421 exit when not Exception_Junk (Stm);
6422 Check_Statement_Sequence
6423 (Statements (Handled_Statement_Sequence (Next (Stm))));
6428 exit when Nkind (Stm) /= N_Goto_Statement;
6429 exit when not Exception_Junk (Stm);
6433 -- Don't count pragmas
6435 while Nkind (Last_Stm) = N_Pragma
6437 -- Don't count call to SS_Release (can happen after Raise_Exception)
6440 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6442 Nkind (Name (Last_Stm)) = N_Identifier
6444 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6446 -- Don't count exception junk
6449 (Nkind_In (Last_Stm, N_Goto_Statement,
6451 N_Object_Declaration)
6452 and then Exception_Junk (Last_Stm))
6453 or else Nkind (Last_Stm) in N_Push_xxx_Label
6454 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6456 -- Inserted code, such as finalization calls, is irrelevant: we only
6457 -- need to check original source.
6459 or else Is_Rewrite_Insertion (Last_Stm)
6464 -- Here we have the "real" last statement
6466 Kind := Nkind (Last_Stm);
6468 -- Transfer of control, OK. Note that in the No_Return procedure
6469 -- case, we already diagnosed any explicit return statements, so
6470 -- we can treat them as OK in this context.
6472 if Is_Transfer (Last_Stm) then
6475 -- Check cases of explicit non-indirect procedure calls
6477 elsif Kind = N_Procedure_Call_Statement
6478 and then Is_Entity_Name (Name (Last_Stm))
6480 -- Check call to Raise_Exception procedure which is treated
6481 -- specially, as is a call to Reraise_Occurrence.
6483 -- We suppress the warning in these cases since it is likely that
6484 -- the programmer really does not expect to deal with the case
6485 -- of Null_Occurrence, and thus would find a warning about a
6486 -- missing return curious, and raising Program_Error does not
6487 -- seem such a bad behavior if this does occur.
6489 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6490 -- behavior will be to raise Constraint_Error (see AI-329).
6492 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6494 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6496 Raise_Exception_Call := True;
6498 -- For Raise_Exception call, test first argument, if it is
6499 -- an attribute reference for a 'Identity call, then we know
6500 -- that the call cannot possibly return.
6503 Arg : constant Node_Id :=
6504 Original_Node (First_Actual (Last_Stm));
6506 if Nkind (Arg) = N_Attribute_Reference
6507 and then Attribute_Name (Arg) = Name_Identity
6514 -- If statement, need to look inside if there is an else and check
6515 -- each constituent statement sequence for proper termination.
6517 elsif Kind = N_If_Statement
6518 and then Present (Else_Statements (Last_Stm))
6520 Check_Statement_Sequence (Then_Statements (Last_Stm));
6521 Check_Statement_Sequence (Else_Statements (Last_Stm));
6523 if Present (Elsif_Parts (Last_Stm)) then
6525 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6528 while Present (Elsif_Part) loop
6529 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6537 -- Case statement, check each case for proper termination
6539 elsif Kind = N_Case_Statement then
6543 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6544 while Present (Case_Alt) loop
6545 Check_Statement_Sequence (Statements (Case_Alt));
6546 Next_Non_Pragma (Case_Alt);
6552 -- Block statement, check its handled sequence of statements
6554 elsif Kind = N_Block_Statement then
6560 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6569 -- Loop statement. If there is an iteration scheme, we can definitely
6570 -- fall out of the loop. Similarly if there is an exit statement, we
6571 -- can fall out. In either case we need a following return.
6573 elsif Kind = N_Loop_Statement then
6574 if Present (Iteration_Scheme (Last_Stm))
6575 or else Has_Exit (Entity (Identifier (Last_Stm)))
6579 -- A loop with no exit statement or iteration scheme is either
6580 -- an infinite loop, or it has some other exit (raise/return).
6581 -- In either case, no warning is required.
6587 -- Timed entry call, check entry call and delay alternatives
6589 -- Note: in expanded code, the timed entry call has been converted
6590 -- to a set of expanded statements on which the check will work
6591 -- correctly in any case.
6593 elsif Kind = N_Timed_Entry_Call then
6595 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6596 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6599 -- If statement sequence of entry call alternative is missing,
6600 -- then we can definitely fall through, and we post the error
6601 -- message on the entry call alternative itself.
6603 if No (Statements (ECA)) then
6606 -- If statement sequence of delay alternative is missing, then
6607 -- we can definitely fall through, and we post the error
6608 -- message on the delay alternative itself.
6610 -- Note: if both ECA and DCA are missing the return, then we
6611 -- post only one message, should be enough to fix the bugs.
6612 -- If not we will get a message next time on the DCA when the
6615 elsif No (Statements (DCA)) then
6618 -- Else check both statement sequences
6621 Check_Statement_Sequence (Statements (ECA));
6622 Check_Statement_Sequence (Statements (DCA));
6627 -- Conditional entry call, check entry call and else part
6629 -- Note: in expanded code, the conditional entry call has been
6630 -- converted to a set of expanded statements on which the check
6631 -- will work correctly in any case.
6633 elsif Kind = N_Conditional_Entry_Call then
6635 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6638 -- If statement sequence of entry call alternative is missing,
6639 -- then we can definitely fall through, and we post the error
6640 -- message on the entry call alternative itself.
6642 if No (Statements (ECA)) then
6645 -- Else check statement sequence and else part
6648 Check_Statement_Sequence (Statements (ECA));
6649 Check_Statement_Sequence (Else_Statements (Last_Stm));
6655 -- If we fall through, issue appropriate message
6659 -- Kill warning if last statement is a raise exception call,
6660 -- or a pragma Assert (False). Note that with assertions enabled,
6661 -- such a pragma has been converted into a raise exception call
6662 -- already, so the Assert_False is for the assertions off case.
6664 if not Raise_Exception_Call and then not Assert_False then
6666 -- In GNATprove mode, it is an error to have a missing return
6668 Error_Msg_Warn := SPARK_Mode /= On;
6670 -- Issue error message or warning
6673 ("RETURN statement missing following this statement<<!",
6676 ("\Program_Error ]<<!", Last_Stm);
6679 -- Note: we set Err even though we have not issued a warning
6680 -- because we still have a case of a missing return. This is
6681 -- an extremely marginal case, probably will never be noticed
6682 -- but we might as well get it right.
6686 -- Otherwise we have the case of a procedure marked No_Return
6689 if not Raise_Exception_Call then
6690 if GNATprove_Mode then
6692 ("implied return after this statement "
6693 & "would have raised Program_Error", Last_Stm);
6696 ("implied return after this statement "
6697 & "will raise Program_Error??", Last_Stm);
6700 Error_Msg_Warn := SPARK_Mode /= On;
6702 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6706 RE : constant Node_Id :=
6707 Make_Raise_Program_Error (Sloc (Last_Stm),
6708 Reason => PE_Implicit_Return);
6710 Insert_After (Last_Stm, RE);
6714 end Check_Statement_Sequence;
6716 -- Start of processing for Check_Returns
6720 Check_Statement_Sequence (Statements (HSS));
6722 if Present (Exception_Handlers (HSS)) then
6723 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6724 while Present (Handler) loop
6725 Check_Statement_Sequence (Statements (Handler));
6726 Next_Non_Pragma (Handler);
6731 ----------------------------
6732 -- Check_Subprogram_Order --
6733 ----------------------------
6735 procedure Check_Subprogram_Order (N : Node_Id) is
6737 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6738 -- This is used to check if S1 > S2 in the sense required by this test,
6739 -- for example nameab < namec, but name2 < name10.
6741 -----------------------------
6742 -- Subprogram_Name_Greater --
6743 -----------------------------
6745 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6750 -- Deal with special case where names are identical except for a
6751 -- numerical suffix. These are handled specially, taking the numeric
6752 -- ordering from the suffix into account.
6755 while S1 (L1) in '0' .. '9' loop
6760 while S2 (L2) in '0' .. '9' loop
6764 -- If non-numeric parts non-equal, do straight compare
6766 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6769 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6770 -- that a missing suffix is treated as numeric zero in this test.
6774 while L1 < S1'Last loop
6776 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6780 while L2 < S2'Last loop
6782 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6787 end Subprogram_Name_Greater;
6789 -- Start of processing for Check_Subprogram_Order
6792 -- Check body in alpha order if this is option
6795 and then Style_Check_Order_Subprograms
6796 and then Nkind (N) = N_Subprogram_Body
6797 and then Comes_From_Source (N)
6798 and then In_Extended_Main_Source_Unit (N)
6802 renames Scope_Stack.Table
6803 (Scope_Stack.Last).Last_Subprogram_Name;
6805 Body_Id : constant Entity_Id :=
6806 Defining_Entity (Specification (N));
6809 Get_Decoded_Name_String (Chars (Body_Id));
6812 if Subprogram_Name_Greater
6813 (LSN.all, Name_Buffer (1 .. Name_Len))
6815 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6821 LSN := new String'(Name_Buffer (1 .. Name_Len));
6824 end Check_Subprogram_Order;
6826 ------------------------------
6827 -- Check_Subtype_Conformant --
6828 ------------------------------
6830 procedure Check_Subtype_Conformant
6831 (New_Id : Entity_Id;
6833 Err_Loc : Node_Id := Empty;
6834 Skip_Controlling_Formals : Boolean := False;
6835 Get_Inst : Boolean := False)
6838 pragma Warnings (Off, Result);
6841 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6842 Skip_Controlling_Formals => Skip_Controlling_Formals,
6843 Get_Inst => Get_Inst);
6844 end Check_Subtype_Conformant;
6846 -----------------------------------
6847 -- Check_Synchronized_Overriding --
6848 -----------------------------------
6850 procedure Check_Synchronized_Overriding
6851 (Def_Id : Entity_Id;
6852 Overridden_Subp : out Entity_Id)
6854 Ifaces_List : Elist_Id;
6858 function Matches_Prefixed_View_Profile
6859 (Prim_Params : List_Id;
6860 Iface_Params : List_Id) return Boolean;
6861 -- Determine whether a subprogram's parameter profile Prim_Params
6862 -- matches that of a potentially overridden interface subprogram
6863 -- Iface_Params. Also determine if the type of first parameter of
6864 -- Iface_Params is an implemented interface.
6866 -----------------------------------
6867 -- Matches_Prefixed_View_Profile --
6868 -----------------------------------
6870 function Matches_Prefixed_View_Profile
6871 (Prim_Params : List_Id;
6872 Iface_Params : List_Id) return Boolean
6874 function Is_Implemented
6875 (Ifaces_List : Elist_Id;
6876 Iface : Entity_Id) return Boolean;
6877 -- Determine if Iface is implemented by the current task or
6880 --------------------
6881 -- Is_Implemented --
6882 --------------------
6884 function Is_Implemented
6885 (Ifaces_List : Elist_Id;
6886 Iface : Entity_Id) return Boolean
6888 Iface_Elmt : Elmt_Id;
6891 Iface_Elmt := First_Elmt (Ifaces_List);
6892 while Present (Iface_Elmt) loop
6893 if Node (Iface_Elmt) = Iface then
6897 Next_Elmt (Iface_Elmt);
6905 Iface_Id : Entity_Id;
6906 Iface_Param : Node_Id;
6907 Iface_Typ : Entity_Id;
6908 Prim_Id : Entity_Id;
6909 Prim_Param : Node_Id;
6910 Prim_Typ : Entity_Id;
6912 -- Start of processing for Matches_Prefixed_View_Profile
6915 Iface_Param := First (Iface_Params);
6916 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
6918 if Is_Access_Type (Iface_Typ) then
6919 Iface_Typ := Designated_Type (Iface_Typ);
6922 Prim_Param := First (Prim_Params);
6924 -- The first parameter of the potentially overridden subprogram must
6925 -- be an interface implemented by Prim.
6927 if not Is_Interface (Iface_Typ)
6928 or else not Is_Implemented (Ifaces_List, Iface_Typ)
6933 -- The checks on the object parameters are done, so move on to the
6934 -- rest of the parameters.
6936 if not In_Scope then
6937 Prim_Param := Next (Prim_Param);
6940 Iface_Param := Next (Iface_Param);
6941 while Present (Iface_Param) and then Present (Prim_Param) loop
6942 Iface_Id := Defining_Identifier (Iface_Param);
6943 Iface_Typ := Find_Parameter_Type (Iface_Param);
6945 Prim_Id := Defining_Identifier (Prim_Param);
6946 Prim_Typ := Find_Parameter_Type (Prim_Param);
6948 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
6949 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
6950 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
6952 Iface_Typ := Designated_Type (Iface_Typ);
6953 Prim_Typ := Designated_Type (Prim_Typ);
6956 -- Case of multiple interface types inside a parameter profile
6958 -- (Obj_Param : in out Iface; ...; Param : Iface)
6960 -- If the interface type is implemented, then the matching type in
6961 -- the primitive should be the implementing record type.
6963 if Ekind (Iface_Typ) = E_Record_Type
6964 and then Is_Interface (Iface_Typ)
6965 and then Is_Implemented (Ifaces_List, Iface_Typ)
6967 if Prim_Typ /= Typ then
6971 -- The two parameters must be both mode and subtype conformant
6973 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
6975 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
6984 -- One of the two lists contains more parameters than the other
6986 if Present (Iface_Param) or else Present (Prim_Param) then
6991 end Matches_Prefixed_View_Profile;
6993 -- Start of processing for Check_Synchronized_Overriding
6996 Overridden_Subp := Empty;
6998 -- Def_Id must be an entry or a subprogram. We should skip predefined
6999 -- primitives internally generated by the front end; however at this
7000 -- stage predefined primitives are still not fully decorated. As a
7001 -- minor optimization we skip here internally generated subprograms.
7003 if (Ekind (Def_Id) /= E_Entry
7004 and then Ekind (Def_Id) /= E_Function
7005 and then Ekind (Def_Id) /= E_Procedure)
7006 or else not Comes_From_Source (Def_Id)
7011 -- Search for the concurrent declaration since it contains the list of
7012 -- all implemented interfaces. In this case, the subprogram is declared
7013 -- within the scope of a protected or a task type.
7015 if Present (Scope (Def_Id))
7016 and then Is_Concurrent_Type (Scope (Def_Id))
7017 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7019 Typ := Scope (Def_Id);
7022 -- The enclosing scope is not a synchronized type and the subprogram
7025 elsif No (First_Formal (Def_Id)) then
7028 -- The subprogram has formals and hence it may be a primitive of a
7032 Typ := Etype (First_Formal (Def_Id));
7034 if Is_Access_Type (Typ) then
7035 Typ := Directly_Designated_Type (Typ);
7038 if Is_Concurrent_Type (Typ)
7039 and then not Is_Generic_Actual_Type (Typ)
7043 -- This case occurs when the concurrent type is declared within a
7044 -- generic unit. As a result the corresponding record has been built
7045 -- and used as the type of the first formal, we just have to retrieve
7046 -- the corresponding concurrent type.
7048 elsif Is_Concurrent_Record_Type (Typ)
7049 and then not Is_Class_Wide_Type (Typ)
7050 and then Present (Corresponding_Concurrent_Type (Typ))
7052 Typ := Corresponding_Concurrent_Type (Typ);
7060 -- There is no overriding to check if this is an inherited operation in
7061 -- a type derivation for a generic actual.
7063 Collect_Interfaces (Typ, Ifaces_List);
7065 if Is_Empty_Elmt_List (Ifaces_List) then
7069 -- Determine whether entry or subprogram Def_Id overrides a primitive
7070 -- operation that belongs to one of the interfaces in Ifaces_List.
7073 Candidate : Entity_Id := Empty;
7074 Hom : Entity_Id := Empty;
7075 Subp : Entity_Id := Empty;
7078 -- Traverse the homonym chain, looking for a potentially overridden
7079 -- subprogram that belongs to an implemented interface.
7081 Hom := Current_Entity_In_Scope (Def_Id);
7082 while Present (Hom) loop
7086 or else not Is_Overloadable (Subp)
7087 or else not Is_Primitive (Subp)
7088 or else not Is_Dispatching_Operation (Subp)
7089 or else not Present (Find_Dispatching_Type (Subp))
7090 or else not Is_Interface (Find_Dispatching_Type (Subp))
7094 -- Entries and procedures can override abstract or null interface
7097 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7098 and then Ekind (Subp) = E_Procedure
7099 and then Matches_Prefixed_View_Profile
7100 (Parameter_Specifications (Parent (Def_Id)),
7101 Parameter_Specifications (Parent (Subp)))
7105 -- For an overridden subprogram Subp, check whether the mode
7106 -- of its first parameter is correct depending on the kind of
7107 -- synchronized type.
7110 Formal : constant Node_Id := First_Formal (Candidate);
7113 -- In order for an entry or a protected procedure to
7114 -- override, the first parameter of the overridden routine
7115 -- must be of mode "out", "in out", or access-to-variable.
7117 if Ekind_In (Candidate, E_Entry, E_Procedure)
7118 and then Is_Protected_Type (Typ)
7119 and then Ekind (Formal) /= E_In_Out_Parameter
7120 and then Ekind (Formal) /= E_Out_Parameter
7121 and then Nkind (Parameter_Type (Parent (Formal))) /=
7126 -- All other cases are OK since a task entry or routine does
7127 -- not have a restriction on the mode of the first parameter
7128 -- of the overridden interface routine.
7131 Overridden_Subp := Candidate;
7136 -- Functions can override abstract interface functions
7138 elsif Ekind (Def_Id) = E_Function
7139 and then Ekind (Subp) = E_Function
7140 and then Matches_Prefixed_View_Profile
7141 (Parameter_Specifications (Parent (Def_Id)),
7142 Parameter_Specifications (Parent (Subp)))
7143 and then Etype (Def_Id) = Etype (Subp)
7147 -- If an inherited subprogram is implemented by a protected
7148 -- function, then the first parameter of the inherited
7149 -- subprogram shall be of mode in, but not an access-to-
7150 -- variable parameter (RM 9.4(11/9)).
7152 if Present (First_Formal (Subp))
7153 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7155 (not Is_Access_Type (Etype (First_Formal (Subp)))
7157 Is_Access_Constant (Etype (First_Formal (Subp))))
7159 Overridden_Subp := Subp;
7164 Hom := Homonym (Hom);
7167 -- After examining all candidates for overriding, we are left with
7168 -- the best match, which is a mode-incompatible interface routine.
7170 if In_Scope and then Present (Candidate) then
7171 Error_Msg_PT (Def_Id, Candidate);
7174 Overridden_Subp := Candidate;
7177 end Check_Synchronized_Overriding;
7179 ---------------------------
7180 -- Check_Type_Conformant --
7181 ---------------------------
7183 procedure Check_Type_Conformant
7184 (New_Id : Entity_Id;
7186 Err_Loc : Node_Id := Empty)
7189 pragma Warnings (Off, Result);
7192 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7193 end Check_Type_Conformant;
7195 ---------------------------
7196 -- Can_Override_Operator --
7197 ---------------------------
7199 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7203 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7207 Typ := Base_Type (Etype (First_Formal (Subp)));
7209 -- Check explicitly that the operation is a primitive of the type
7211 return Operator_Matches_Spec (Subp, Subp)
7212 and then not Is_Generic_Type (Typ)
7213 and then Scope (Subp) = Scope (Typ)
7214 and then not Is_Class_Wide_Type (Typ);
7216 end Can_Override_Operator;
7218 ----------------------
7219 -- Conforming_Types --
7220 ----------------------
7222 function Conforming_Types
7225 Ctype : Conformance_Type;
7226 Get_Inst : Boolean := False) return Boolean
7228 function Base_Types_Match
7230 Typ_2 : Entity_Id) return Boolean;
7231 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7232 -- in different scopes (e.g. parent and child instances), then verify
7233 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7234 -- the same subtype chain. The whole purpose of this procedure is to
7235 -- prevent spurious ambiguities in an instantiation that may arise if
7236 -- two distinct generic types are instantiated with the same actual.
7238 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7239 -- An access parameter can designate an incomplete type. If the
7240 -- incomplete type is the limited view of a type from a limited_
7241 -- with_clause, check whether the non-limited view is available.
7242 -- If it is a (non-limited) incomplete type, get the full view.
7244 function Matches_Limited_With_View
7246 Typ_2 : Entity_Id) return Boolean;
7247 -- Returns True if and only if either Typ_1 denotes a limited view of
7248 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7249 -- the limited with view of a type is used in a subprogram declaration
7250 -- and the subprogram body is in the scope of a regular with clause for
7251 -- the same unit. In such a case, the two type entities are considered
7252 -- identical for purposes of conformance checking.
7254 ----------------------
7255 -- Base_Types_Match --
7256 ----------------------
7258 function Base_Types_Match
7260 Typ_2 : Entity_Id) return Boolean
7262 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7263 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7266 if Typ_1 = Typ_2 then
7269 elsif Base_1 = Base_2 then
7271 -- The following is too permissive. A more precise test should
7272 -- check that the generic actual is an ancestor subtype of the
7275 -- See code in Find_Corresponding_Spec that applies an additional
7276 -- filter to handle accidental amiguities in instances.
7279 not Is_Generic_Actual_Type (Typ_1)
7280 or else not Is_Generic_Actual_Type (Typ_2)
7281 or else Scope (Typ_1) /= Scope (Typ_2);
7283 -- If Typ_2 is a generic actual type it is declared as the subtype of
7284 -- the actual. If that actual is itself a subtype we need to use its
7285 -- own base type to check for compatibility.
7287 elsif Ekind (Base_2) = Ekind (Typ_2)
7288 and then Base_1 = Base_Type (Base_2)
7292 elsif Ekind (Base_1) = Ekind (Typ_1)
7293 and then Base_2 = Base_Type (Base_1)
7300 end Base_Types_Match;
7302 --------------------------
7303 -- Find_Designated_Type --
7304 --------------------------
7306 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7310 Desig := Directly_Designated_Type (Typ);
7312 if Ekind (Desig) = E_Incomplete_Type then
7314 -- If regular incomplete type, get full view if available
7316 if Present (Full_View (Desig)) then
7317 Desig := Full_View (Desig);
7319 -- If limited view of a type, get non-limited view if available,
7320 -- and check again for a regular incomplete type.
7322 elsif Present (Non_Limited_View (Desig)) then
7323 Desig := Get_Full_View (Non_Limited_View (Desig));
7328 end Find_Designated_Type;
7330 -------------------------------
7331 -- Matches_Limited_With_View --
7332 -------------------------------
7334 function Matches_Limited_With_View
7336 Typ_2 : Entity_Id) return Boolean
7338 function Is_Matching_Limited_View
7340 View : Entity_Id) return Boolean;
7341 -- Determine whether non-limited view View denotes type Typ in some
7342 -- conformant fashion.
7344 ------------------------------
7345 -- Is_Matching_Limited_View --
7346 ------------------------------
7348 function Is_Matching_Limited_View
7350 View : Entity_Id) return Boolean
7352 Root_Typ : Entity_Id;
7353 Root_View : Entity_Id;
7356 -- The non-limited view directly denotes the type
7361 -- The type is a subtype of the non-limited view
7363 elsif Is_Subtype_Of (Typ, View) then
7366 -- Both the non-limited view and the type denote class-wide types
7368 elsif Is_Class_Wide_Type (Typ)
7369 and then Is_Class_Wide_Type (View)
7371 Root_Typ := Root_Type (Typ);
7372 Root_View := Root_Type (View);
7374 if Root_Typ = Root_View then
7377 -- An incomplete tagged type and its full view may receive two
7378 -- distinct class-wide types when the related package has not
7379 -- been analyzed yet.
7382 -- type T is tagged; -- CW_1
7383 -- type T is tagged null record; -- CW_2
7386 -- This is because the package lacks any semantic information
7387 -- that may eventually link both views of T. As a consequence,
7388 -- a client of the limited view of Pack will see CW_2 while a
7389 -- client of the non-limited view of Pack will see CW_1.
7391 elsif Is_Incomplete_Type (Root_Typ)
7392 and then Present (Full_View (Root_Typ))
7393 and then Full_View (Root_Typ) = Root_View
7397 elsif Is_Incomplete_Type (Root_View)
7398 and then Present (Full_View (Root_View))
7399 and then Full_View (Root_View) = Root_Typ
7406 end Is_Matching_Limited_View;
7408 -- Start of processing for Matches_Limited_With_View
7411 -- In some cases a type imported through a limited_with clause, and
7412 -- its non-limited view are both visible, for example in an anonymous
7413 -- access-to-class-wide type in a formal, or when building the body
7414 -- for a subprogram renaming after the subprogram has been frozen.
7415 -- In these cases both entities designate the same type. In addition,
7416 -- if one of them is an actual in an instance, it may be a subtype of
7417 -- the non-limited view of the other.
7419 if From_Limited_With (Typ_1)
7420 and then From_Limited_With (Typ_2)
7421 and then Available_View (Typ_1) = Available_View (Typ_2)
7425 elsif From_Limited_With (Typ_1) then
7426 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7428 elsif From_Limited_With (Typ_2) then
7429 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7434 end Matches_Limited_With_View;
7438 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7440 Type_1 : Entity_Id := T1;
7441 Type_2 : Entity_Id := T2;
7443 -- Start of processing for Conforming_Types
7446 -- The context is an instance association for a formal access-to-
7447 -- subprogram type; the formal parameter types require mapping because
7448 -- they may denote other formal parameters of the generic unit.
7451 Type_1 := Get_Instance_Of (T1);
7452 Type_2 := Get_Instance_Of (T2);
7455 -- If one of the types is a view of the other introduced by a limited
7456 -- with clause, treat these as conforming for all purposes.
7458 if Matches_Limited_With_View (T1, T2) then
7461 elsif Base_Types_Match (Type_1, Type_2) then
7462 if Ctype <= Mode_Conformant then
7467 Subtypes_Statically_Match (Type_1, Type_2)
7468 and then Dimensions_Match (Type_1, Type_2);
7471 elsif Is_Incomplete_Or_Private_Type (Type_1)
7472 and then Present (Full_View (Type_1))
7473 and then Base_Types_Match (Full_View (Type_1), Type_2)
7476 Ctype <= Mode_Conformant
7477 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7479 elsif Ekind (Type_2) = E_Incomplete_Type
7480 and then Present (Full_View (Type_2))
7481 and then Base_Types_Match (Type_1, Full_View (Type_2))
7484 Ctype <= Mode_Conformant
7485 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7487 elsif Is_Private_Type (Type_2)
7488 and then In_Instance
7489 and then Present (Full_View (Type_2))
7490 and then Base_Types_Match (Type_1, Full_View (Type_2))
7493 Ctype <= Mode_Conformant
7494 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7496 -- Another confusion between views in a nested instance with an
7497 -- actual private type whose full view is not in scope.
7499 elsif Ekind (Type_2) = E_Private_Subtype
7500 and then In_Instance
7501 and then Etype (Type_2) = Type_1
7505 -- In Ada 2012, incomplete types (including limited views) can appear
7506 -- as actuals in instantiations.
7508 elsif Is_Incomplete_Type (Type_1)
7509 and then Is_Incomplete_Type (Type_2)
7510 and then (Used_As_Generic_Actual (Type_1)
7511 or else Used_As_Generic_Actual (Type_2))
7516 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7517 -- treated recursively because they carry a signature. As far as
7518 -- conformance is concerned, convention plays no role, and either
7519 -- or both could be access to protected subprograms.
7521 Are_Anonymous_Access_To_Subprogram_Types :=
7522 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7523 E_Anonymous_Access_Protected_Subprogram_Type)
7525 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7526 E_Anonymous_Access_Protected_Subprogram_Type);
7528 -- Test anonymous access type case. For this case, static subtype
7529 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7530 -- the base types because we may have built internal subtype entities
7531 -- to handle null-excluding types (see Process_Formals).
7533 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7535 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7537 -- Ada 2005 (AI-254)
7539 or else Are_Anonymous_Access_To_Subprogram_Types
7542 Desig_1 : Entity_Id;
7543 Desig_2 : Entity_Id;
7546 -- In Ada 2005, access constant indicators must match for
7547 -- subtype conformance.
7549 if Ada_Version >= Ada_2005
7550 and then Ctype >= Subtype_Conformant
7552 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7557 Desig_1 := Find_Designated_Type (Type_1);
7558 Desig_2 := Find_Designated_Type (Type_2);
7560 -- If the context is an instance association for a formal
7561 -- access-to-subprogram type; formal access parameter designated
7562 -- types require mapping because they may denote other formal
7563 -- parameters of the generic unit.
7566 Desig_1 := Get_Instance_Of (Desig_1);
7567 Desig_2 := Get_Instance_Of (Desig_2);
7570 -- It is possible for a Class_Wide_Type to be introduced for an
7571 -- incomplete type, in which case there is a separate class_ wide
7572 -- type for the full view. The types conform if their Etypes
7573 -- conform, i.e. one may be the full view of the other. This can
7574 -- only happen in the context of an access parameter, other uses
7575 -- of an incomplete Class_Wide_Type are illegal.
7577 if Is_Class_Wide_Type (Desig_1)
7579 Is_Class_Wide_Type (Desig_2)
7583 (Etype (Base_Type (Desig_1)),
7584 Etype (Base_Type (Desig_2)), Ctype);
7586 elsif Are_Anonymous_Access_To_Subprogram_Types then
7587 if Ada_Version < Ada_2005 then
7589 Ctype = Type_Conformant
7590 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7592 -- We must check the conformance of the signatures themselves
7596 Conformant : Boolean;
7599 (Desig_1, Desig_2, Ctype, False, Conformant);
7604 -- A limited view of an actual matches the corresponding
7605 -- incomplete formal.
7607 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7608 and then From_Limited_With (Desig_2)
7609 and then Used_As_Generic_Actual (Etype (Desig_2))
7614 return Base_Type (Desig_1) = Base_Type (Desig_2)
7615 and then (Ctype = Type_Conformant
7617 Subtypes_Statically_Match (Desig_1, Desig_2));
7621 -- Otherwise definitely no match
7624 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7625 and then Is_Access_Type (Type_2))
7626 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7627 and then Is_Access_Type (Type_1)))
7630 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7632 May_Hide_Profile := True;
7637 end Conforming_Types;
7639 --------------------------
7640 -- Create_Extra_Formals --
7641 --------------------------
7643 procedure Create_Extra_Formals (E : Entity_Id) is
7644 First_Extra : Entity_Id := Empty;
7646 Last_Extra : Entity_Id := Empty;
7648 function Add_Extra_Formal
7649 (Assoc_Entity : Entity_Id;
7652 Suffix : String) return Entity_Id;
7653 -- Add an extra formal to the current list of formals and extra formals.
7654 -- The extra formal is added to the end of the list of extra formals,
7655 -- and also returned as the result. These formals are always of mode IN.
7656 -- The new formal has the type Typ, is declared in Scope, and its name
7657 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7658 -- The following suffixes are currently used. They should not be changed
7659 -- without coordinating with CodePeer, which makes use of these to
7660 -- provide better messages.
7662 -- O denotes the Constrained bit.
7663 -- L denotes the accessibility level.
7664 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7665 -- the full list in exp_ch6.BIP_Formal_Kind.
7667 ----------------------
7668 -- Add_Extra_Formal --
7669 ----------------------
7671 function Add_Extra_Formal
7672 (Assoc_Entity : Entity_Id;
7675 Suffix : String) return Entity_Id
7677 EF : constant Entity_Id :=
7678 Make_Defining_Identifier (Sloc (Assoc_Entity),
7679 Chars => New_External_Name (Chars (Assoc_Entity),
7683 -- A little optimization. Never generate an extra formal for the
7684 -- _init operand of an initialization procedure, since it could
7687 if Chars (Formal) = Name_uInit then
7691 Set_Ekind (EF, E_In_Parameter);
7692 Set_Actual_Subtype (EF, Typ);
7693 Set_Etype (EF, Typ);
7694 Set_Scope (EF, Scope);
7695 Set_Mechanism (EF, Default_Mechanism);
7696 Set_Formal_Validity (EF);
7698 if No (First_Extra) then
7700 Set_Extra_Formals (Scope, First_Extra);
7703 if Present (Last_Extra) then
7704 Set_Extra_Formal (Last_Extra, EF);
7710 end Add_Extra_Formal;
7714 Formal_Type : Entity_Id;
7715 P_Formal : Entity_Id := Empty;
7717 -- Start of processing for Create_Extra_Formals
7720 -- We never generate extra formals if expansion is not active because we
7721 -- don't need them unless we are generating code.
7723 if not Expander_Active then
7727 -- No need to generate extra formals in interface thunks whose target
7728 -- primitive has no extra formals.
7730 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7734 -- If this is a derived subprogram then the subtypes of the parent
7735 -- subprogram's formal parameters will be used to determine the need
7736 -- for extra formals.
7738 if Is_Overloadable (E) and then Present (Alias (E)) then
7739 P_Formal := First_Formal (Alias (E));
7742 Formal := First_Formal (E);
7743 while Present (Formal) loop
7744 Last_Extra := Formal;
7745 Next_Formal (Formal);
7748 -- If Extra_Formals were already created, don't do it again. This
7749 -- situation may arise for subprogram types created as part of
7750 -- dispatching calls (see Expand_Dispatching_Call)
7752 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7756 -- If the subprogram is a predefined dispatching subprogram then don't
7757 -- generate any extra constrained or accessibility level formals. In
7758 -- general we suppress these for internal subprograms (by not calling
7759 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7760 -- generated stream attributes do get passed through because extra
7761 -- build-in-place formals are needed in some cases (limited 'Input).
7763 if Is_Predefined_Internal_Operation (E) then
7764 goto Test_For_Func_Result_Extras;
7767 Formal := First_Formal (E);
7768 while Present (Formal) loop
7770 -- Create extra formal for supporting the attribute 'Constrained.
7771 -- The case of a private type view without discriminants also
7772 -- requires the extra formal if the underlying type has defaulted
7775 if Ekind (Formal) /= E_In_Parameter then
7776 if Present (P_Formal) then
7777 Formal_Type := Etype (P_Formal);
7779 Formal_Type := Etype (Formal);
7782 -- Do not produce extra formals for Unchecked_Union parameters.
7783 -- Jump directly to the end of the loop.
7785 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7786 goto Skip_Extra_Formal_Generation;
7789 if not Has_Discriminants (Formal_Type)
7790 and then Ekind (Formal_Type) in Private_Kind
7791 and then Present (Underlying_Type (Formal_Type))
7793 Formal_Type := Underlying_Type (Formal_Type);
7796 -- Suppress the extra formal if formal's subtype is constrained or
7797 -- indefinite, or we're compiling for Ada 2012 and the underlying
7798 -- type is tagged and limited. In Ada 2012, a limited tagged type
7799 -- can have defaulted discriminants, but 'Constrained is required
7800 -- to return True, so the formal is never needed (see AI05-0214).
7801 -- Note that this ensures consistency of calling sequences for
7802 -- dispatching operations when some types in a class have defaults
7803 -- on discriminants and others do not (and requiring the extra
7804 -- formal would introduce distributed overhead).
7806 -- If the type does not have a completion yet, treat as prior to
7807 -- Ada 2012 for consistency.
7809 if Has_Discriminants (Formal_Type)
7810 and then not Is_Constrained (Formal_Type)
7811 and then Is_Definite_Subtype (Formal_Type)
7812 and then (Ada_Version < Ada_2012
7813 or else No (Underlying_Type (Formal_Type))
7815 (Is_Limited_Type (Formal_Type)
7818 (Underlying_Type (Formal_Type)))))
7820 Set_Extra_Constrained
7821 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7825 -- Create extra formal for supporting accessibility checking. This
7826 -- is done for both anonymous access formals and formals of named
7827 -- access types that are marked as controlling formals. The latter
7828 -- case can occur when Expand_Dispatching_Call creates a subprogram
7829 -- type and substitutes the types of access-to-class-wide actuals
7830 -- for the anonymous access-to-specific-type of controlling formals.
7831 -- Base_Type is applied because in cases where there is a null
7832 -- exclusion the formal may have an access subtype.
7834 -- This is suppressed if we specifically suppress accessibility
7835 -- checks at the package level for either the subprogram, or the
7836 -- package in which it resides. However, we do not suppress it
7837 -- simply if the scope has accessibility checks suppressed, since
7838 -- this could cause trouble when clients are compiled with a
7839 -- different suppression setting. The explicit checks at the
7840 -- package level are safe from this point of view.
7842 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7843 or else (Is_Controlling_Formal (Formal)
7844 and then Is_Access_Type (Base_Type (Etype (Formal)))))
7846 (Explicit_Suppress (E, Accessibility_Check)
7848 Explicit_Suppress (Scope (E), Accessibility_Check))
7851 or else Present (Extra_Accessibility (P_Formal)))
7853 Set_Extra_Accessibility
7854 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
7857 -- This label is required when skipping extra formal generation for
7858 -- Unchecked_Union parameters.
7860 <<Skip_Extra_Formal_Generation>>
7862 if Present (P_Formal) then
7863 Next_Formal (P_Formal);
7866 Next_Formal (Formal);
7869 <<Test_For_Func_Result_Extras>>
7871 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
7872 -- function call is ... determined by the point of call ...".
7874 if Needs_Result_Accessibility_Level (E) then
7875 Set_Extra_Accessibility_Of_Result
7876 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
7879 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
7880 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
7882 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
7884 Result_Subt : constant Entity_Id := Etype (E);
7885 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
7886 Formal_Typ : Entity_Id;
7887 Subp_Decl : Node_Id;
7889 Discard : Entity_Id;
7890 pragma Warnings (Off, Discard);
7893 -- In the case of functions with unconstrained result subtypes,
7894 -- add a 4-state formal indicating whether the return object is
7895 -- allocated by the caller (1), or should be allocated by the
7896 -- callee on the secondary stack (2), in the global heap (3), or
7897 -- in a user-defined storage pool (4). For the moment we just use
7898 -- Natural for the type of this formal. Note that this formal
7899 -- isn't usually needed in the case where the result subtype is
7900 -- constrained, but it is needed when the function has a tagged
7901 -- result, because generally such functions can be called in a
7902 -- dispatching context and such calls must be handled like calls
7903 -- to a class-wide function.
7905 if Needs_BIP_Alloc_Form (E) then
7908 (E, Standard_Natural,
7909 E, BIP_Formal_Suffix (BIP_Alloc_Form));
7911 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
7912 -- use a user-defined pool. This formal is not added on
7913 -- ZFP as those targets do not support pools.
7915 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
7918 (E, RTE (RE_Root_Storage_Pool_Ptr),
7919 E, BIP_Formal_Suffix (BIP_Storage_Pool));
7923 -- In the case of functions whose result type needs finalization,
7924 -- add an extra formal which represents the finalization master.
7926 if Needs_BIP_Finalization_Master (E) then
7929 (E, RTE (RE_Finalization_Master_Ptr),
7930 E, BIP_Formal_Suffix (BIP_Finalization_Master));
7933 -- When the result type contains tasks, add two extra formals: the
7934 -- master of the tasks to be created, and the caller's activation
7937 if Has_Task (Full_Subt) then
7940 (E, RTE (RE_Master_Id),
7941 E, BIP_Formal_Suffix (BIP_Task_Master));
7944 (E, RTE (RE_Activation_Chain_Access),
7945 E, BIP_Formal_Suffix (BIP_Activation_Chain));
7948 -- All build-in-place functions get an extra formal that will be
7949 -- passed the address of the return object within the caller.
7952 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
7954 Set_Directly_Designated_Type (Formal_Typ, Result_Subt);
7955 Set_Etype (Formal_Typ, Formal_Typ);
7956 Set_Depends_On_Private
7957 (Formal_Typ, Has_Private_Component (Formal_Typ));
7958 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
7959 Set_Is_Access_Constant (Formal_Typ, False);
7961 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
7962 -- the designated type comes from the limited view (for back-end
7965 Set_From_Limited_With
7966 (Formal_Typ, From_Limited_With (Result_Subt));
7968 Layout_Type (Formal_Typ);
7970 -- Force the definition of the Itype in case of internal function
7971 -- calls within the same or nested scope.
7973 if Is_Subprogram_Or_Generic_Subprogram (E) then
7974 Subp_Decl := Parent (E);
7976 -- The insertion point for an Itype reference should be after
7977 -- the unit declaration node of the subprogram. An exception
7978 -- to this are inherited operations from a parent type in which
7979 -- case the derived type acts as their parent.
7981 if Nkind_In (Subp_Decl, N_Function_Specification,
7982 N_Procedure_Specification)
7984 Subp_Decl := Parent (Subp_Decl);
7987 Build_Itype_Reference (Formal_Typ, Subp_Decl);
7992 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
7995 end Create_Extra_Formals;
7997 -----------------------------
7998 -- Enter_Overloaded_Entity --
7999 -----------------------------
8001 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8002 function Matches_Predefined_Op return Boolean;
8003 -- This returns an approximation of whether S matches a predefined
8004 -- operator, based on the operator symbol, and the parameter and result
8005 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8007 ---------------------------
8008 -- Matches_Predefined_Op --
8009 ---------------------------
8011 function Matches_Predefined_Op return Boolean is
8012 Formal_1 : constant Entity_Id := First_Formal (S);
8013 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8014 Op : constant Name_Id := Chars (S);
8015 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8016 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8021 if Present (Formal_2) then
8023 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8026 -- All but "&" and "**" have same-types parameters
8035 if Type_1 /= Type_2 then
8040 -- Check parameter and result types
8048 Is_Boolean_Type (Result_Type)
8049 and then Result_Type = Type_1;
8055 Is_Integer_Type (Result_Type)
8056 and then Result_Type = Type_1;
8064 Is_Numeric_Type (Result_Type)
8065 and then Result_Type = Type_1;
8071 Is_Boolean_Type (Result_Type)
8072 and then not Is_Limited_Type (Type_1);
8080 Is_Boolean_Type (Result_Type)
8081 and then (Is_Array_Type (Type_1)
8082 or else Is_Scalar_Type (Type_1));
8084 when Name_Op_Concat =>
8085 return Is_Array_Type (Result_Type);
8087 when Name_Op_Expon =>
8089 (Is_Integer_Type (Result_Type)
8090 or else Is_Floating_Point_Type (Result_Type))
8091 and then Result_Type = Type_1
8092 and then Type_2 = Standard_Integer;
8095 raise Program_Error;
8108 Is_Numeric_Type (Result_Type)
8109 and then Result_Type = Type_1;
8113 Is_Boolean_Type (Result_Type)
8114 and then Result_Type = Type_1;
8117 raise Program_Error;
8120 end Matches_Predefined_Op;
8124 E : Entity_Id := Current_Entity_In_Scope (S);
8125 C_E : Entity_Id := Current_Entity (S);
8127 -- Start of processing for Enter_Overloaded_Entity
8131 Set_Has_Homonym (E);
8132 Set_Has_Homonym (S);
8135 Set_Is_Immediately_Visible (S);
8136 Set_Scope (S, Current_Scope);
8138 -- Chain new entity if front of homonym in current scope, so that
8139 -- homonyms are contiguous.
8141 if Present (E) and then E /= C_E then
8142 while Homonym (C_E) /= E loop
8143 C_E := Homonym (C_E);
8146 Set_Homonym (C_E, S);
8150 Set_Current_Entity (S);
8155 if Is_Inherited_Operation (S) then
8156 Append_Inherited_Subprogram (S);
8158 Append_Entity (S, Current_Scope);
8161 Set_Public_Status (S);
8163 if Debug_Flag_E then
8164 Write_Str ("New overloaded entity chain: ");
8165 Write_Name (Chars (S));
8168 while Present (E) loop
8169 Write_Str (" "); Write_Int (Int (E));
8176 -- Generate warning for hiding
8179 and then Comes_From_Source (S)
8180 and then In_Extended_Main_Source_Unit (S)
8187 -- Warn unless genuine overloading. Do not emit warning on
8188 -- hiding predefined operators in Standard (these are either an
8189 -- (artifact of our implicit declarations, or simple noise) but
8190 -- keep warning on a operator defined on a local subtype, because
8191 -- of the real danger that different operators may be applied in
8192 -- various parts of the program.
8194 -- Note that if E and S have the same scope, there is never any
8195 -- hiding. Either the two conflict, and the program is illegal,
8196 -- or S is overriding an implicit inherited subprogram.
8198 if Scope (E) /= Scope (S)
8199 and then (not Is_Overloadable (E)
8200 or else Subtype_Conformant (E, S))
8201 and then (Is_Immediately_Visible (E)
8202 or else Is_Potentially_Use_Visible (S))
8204 if Scope (E) = Standard_Standard then
8205 if Nkind (S) = N_Defining_Operator_Symbol
8206 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8208 and then Matches_Predefined_Op
8211 ("declaration of & hides predefined operator?h?", S);
8214 -- E not immediately within Standard
8217 Error_Msg_Sloc := Sloc (E);
8218 Error_Msg_N ("declaration of & hides one #?h?", S);
8223 end Enter_Overloaded_Entity;
8225 -----------------------------
8226 -- Check_Untagged_Equality --
8227 -----------------------------
8229 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8230 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8231 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8235 -- This check applies only if we have a subprogram declaration with an
8236 -- untagged record type.
8238 if Nkind (Decl) /= N_Subprogram_Declaration
8239 or else not Is_Record_Type (Typ)
8240 or else Is_Tagged_Type (Typ)
8245 -- In Ada 2012 case, we will output errors or warnings depending on
8246 -- the setting of debug flag -gnatd.E.
8248 if Ada_Version >= Ada_2012 then
8249 Error_Msg_Warn := Debug_Flag_Dot_EE;
8251 -- In earlier versions of Ada, nothing to do unless we are warning on
8252 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8255 if not Warn_On_Ada_2012_Compatibility then
8260 -- Cases where the type has already been frozen
8262 if Is_Frozen (Typ) then
8264 -- If the type is not declared in a package, or if we are in the body
8265 -- of the package or in some other scope, the new operation is not
8266 -- primitive, and therefore legal, though suspicious. Should we
8267 -- generate a warning in this case ???
8269 if Ekind (Scope (Typ)) /= E_Package
8270 or else Scope (Typ) /= Current_Scope
8274 -- If the type is a generic actual (sub)type, the operation is not
8275 -- primitive either because the base type is declared elsewhere.
8277 elsif Is_Generic_Actual_Type (Typ) then
8280 -- Here we have a definite error of declaration after freezing
8283 if Ada_Version >= Ada_2012 then
8285 ("equality operator must be declared before type & is "
8286 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8288 -- In Ada 2012 mode with error turned to warning, output one
8289 -- more warning to warn that the equality operation may not
8290 -- compose. This is the consequence of ignoring the error.
8292 if Error_Msg_Warn then
8293 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8298 ("equality operator must be declared before type& is "
8299 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8302 -- If we are in the package body, we could just move the
8303 -- declaration to the package spec, so add a message saying that.
8305 if In_Package_Body (Scope (Typ)) then
8306 if Ada_Version >= Ada_2012 then
8308 ("\move declaration to package spec<<", Eq_Op);
8311 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8314 -- Otherwise try to find the freezing point
8317 Obj_Decl := Next (Parent (Typ));
8318 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8319 if Nkind (Obj_Decl) = N_Object_Declaration
8320 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8322 -- Freezing point, output warnings
8324 if Ada_Version >= Ada_2012 then
8326 ("type& is frozen by declaration??", Obj_Decl, Typ);
8328 ("\an equality operator cannot be declared after "
8333 ("type& is frozen by declaration (Ada 2012)?y?",
8336 ("\an equality operator cannot be declared after "
8337 & "this point (Ada 2012)?y?",
8349 -- Here if type is not frozen yet. It is illegal to have a primitive
8350 -- equality declared in the private part if the type is visible.
8352 elsif not In_Same_List (Parent (Typ), Decl)
8353 and then not Is_Limited_Type (Typ)
8355 -- Shouldn't we give an RM reference here???
8357 if Ada_Version >= Ada_2012 then
8359 ("equality operator appears too late<<", Eq_Op);
8362 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8365 -- No error detected
8370 end Check_Untagged_Equality;
8372 -----------------------------
8373 -- Find_Corresponding_Spec --
8374 -----------------------------
8376 function Find_Corresponding_Spec
8378 Post_Error : Boolean := True) return Entity_Id
8380 Spec : constant Node_Id := Specification (N);
8381 Designator : constant Entity_Id := Defining_Entity (Spec);
8385 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8386 -- Even if fully conformant, a body may depend on a generic actual when
8387 -- the spec does not, or vice versa, in which case they were distinct
8388 -- entities in the generic.
8390 -------------------------------
8391 -- Different_Generic_Profile --
8392 -------------------------------
8394 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8397 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8398 -- Check that the types of corresponding formals have the same
8399 -- generic actual if any. We have to account for subtypes of a
8400 -- generic formal, declared between a spec and a body, which may
8401 -- appear distinct in an instance but matched in the generic, and
8402 -- the subtype may be used either in the spec or the body of the
8403 -- subprogram being checked.
8405 -------------------------
8406 -- Same_Generic_Actual --
8407 -------------------------
8409 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8411 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8412 -- Predicate to check whether S1 is a subtype of S2 in the source
8415 -------------------------
8416 -- Is_Declared_Subtype --
8417 -------------------------
8419 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8421 return Comes_From_Source (Parent (S1))
8422 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8423 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8424 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8425 end Is_Declared_Subtype;
8427 -- Start of processing for Same_Generic_Actual
8430 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8431 or else Is_Declared_Subtype (T1, T2)
8432 or else Is_Declared_Subtype (T2, T1);
8433 end Same_Generic_Actual;
8435 -- Start of processing for Different_Generic_Profile
8438 if not In_Instance then
8441 elsif Ekind (E) = E_Function
8442 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8447 F1 := First_Formal (Designator);
8448 F2 := First_Formal (E);
8449 while Present (F1) loop
8450 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8459 end Different_Generic_Profile;
8461 -- Start of processing for Find_Corresponding_Spec
8464 E := Current_Entity (Designator);
8465 while Present (E) loop
8467 -- We are looking for a matching spec. It must have the same scope,
8468 -- and the same name, and either be type conformant, or be the case
8469 -- of a library procedure spec and its body (which belong to one
8470 -- another regardless of whether they are type conformant or not).
8472 if Scope (E) = Current_Scope then
8473 if Current_Scope = Standard_Standard
8474 or else (Ekind (E) = Ekind (Designator)
8475 and then Type_Conformant (E, Designator))
8477 -- Within an instantiation, we know that spec and body are
8478 -- subtype conformant, because they were subtype conformant in
8479 -- the generic. We choose the subtype-conformant entity here as
8480 -- well, to resolve spurious ambiguities in the instance that
8481 -- were not present in the generic (i.e. when two different
8482 -- types are given the same actual). If we are looking for a
8483 -- spec to match a body, full conformance is expected.
8487 -- Inherit the convention and "ghostness" of the matching
8488 -- spec to ensure proper full and subtype conformance.
8490 Set_Convention (Designator, Convention (E));
8492 -- Skip past subprogram bodies and subprogram renamings that
8493 -- may appear to have a matching spec, but that aren't fully
8494 -- conformant with it. That can occur in cases where an
8495 -- actual type causes unrelated homographs in the instance.
8497 if Nkind_In (N, N_Subprogram_Body,
8498 N_Subprogram_Renaming_Declaration)
8499 and then Present (Homonym (E))
8500 and then not Fully_Conformant (Designator, E)
8504 elsif not Subtype_Conformant (Designator, E) then
8507 elsif Different_Generic_Profile (E) then
8512 -- Ada 2012 (AI05-0165): For internally generated bodies of
8513 -- null procedures locate the internally generated spec. We
8514 -- enforce mode conformance since a tagged type may inherit
8515 -- from interfaces several null primitives which differ only
8516 -- in the mode of the formals.
8518 if not (Comes_From_Source (E))
8519 and then Is_Null_Procedure (E)
8520 and then not Mode_Conformant (Designator, E)
8524 -- For null procedures coming from source that are completions,
8525 -- analysis of the generated body will establish the link.
8527 elsif Comes_From_Source (E)
8528 and then Nkind (Spec) = N_Procedure_Specification
8529 and then Null_Present (Spec)
8533 -- Expression functions can be completions, but cannot be
8534 -- completed by an explicit body.
8536 elsif Comes_From_Source (E)
8537 and then Comes_From_Source (N)
8538 and then Nkind (N) = N_Subprogram_Body
8539 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8540 N_Expression_Function
8542 Error_Msg_Sloc := Sloc (E);
8543 Error_Msg_N ("body conflicts with expression function#", N);
8546 elsif not Has_Completion (E) then
8547 if Nkind (N) /= N_Subprogram_Body_Stub then
8548 Set_Corresponding_Spec (N, E);
8551 Set_Has_Completion (E);
8554 elsif Nkind (Parent (N)) = N_Subunit then
8556 -- If this is the proper body of a subunit, the completion
8557 -- flag is set when analyzing the stub.
8561 -- If E is an internal function with a controlling result that
8562 -- was created for an operation inherited by a null extension,
8563 -- it may be overridden by a body without a previous spec (one
8564 -- more reason why these should be shunned). In that case we
8565 -- remove the generated body if present, because the current
8566 -- one is the explicit overriding.
8568 elsif Ekind (E) = E_Function
8569 and then Ada_Version >= Ada_2005
8570 and then not Comes_From_Source (E)
8571 and then Has_Controlling_Result (E)
8572 and then Is_Null_Extension (Etype (E))
8573 and then Comes_From_Source (Spec)
8575 Set_Has_Completion (E, False);
8578 and then Nkind (Parent (E)) = N_Function_Specification
8581 (Unit_Declaration_Node
8582 (Corresponding_Body (Unit_Declaration_Node (E))));
8586 -- If expansion is disabled, or if the wrapper function has
8587 -- not been generated yet, this a late body overriding an
8588 -- inherited operation, or it is an overriding by some other
8589 -- declaration before the controlling result is frozen. In
8590 -- either case this is a declaration of a new entity.
8596 -- If the body already exists, then this is an error unless
8597 -- the previous declaration is the implicit declaration of a
8598 -- derived subprogram. It is also legal for an instance to
8599 -- contain type conformant overloadable declarations (but the
8600 -- generic declaration may not), per 8.3(26/2).
8602 elsif No (Alias (E))
8603 and then not Is_Intrinsic_Subprogram (E)
8604 and then not In_Instance
8607 Error_Msg_Sloc := Sloc (E);
8609 if Is_Imported (E) then
8611 ("body not allowed for imported subprogram & declared#",
8614 Error_Msg_NE ("duplicate body for & declared#", N, E);
8618 -- Child units cannot be overloaded, so a conformance mismatch
8619 -- between body and a previous spec is an error.
8621 elsif Is_Child_Unit (E)
8623 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8625 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8630 ("body of child unit does not match previous declaration", N);
8638 -- On exit, we know that no previous declaration of subprogram exists
8641 end Find_Corresponding_Spec;
8643 ----------------------
8644 -- Fully_Conformant --
8645 ----------------------
8647 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8650 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8652 end Fully_Conformant;
8654 ----------------------------------
8655 -- Fully_Conformant_Expressions --
8656 ----------------------------------
8658 function Fully_Conformant_Expressions
8659 (Given_E1 : Node_Id;
8660 Given_E2 : Node_Id) return Boolean
8662 E1 : constant Node_Id := Original_Node (Given_E1);
8663 E2 : constant Node_Id := Original_Node (Given_E2);
8664 -- We always test conformance on original nodes, since it is possible
8665 -- for analysis and/or expansion to make things look as though they
8666 -- conform when they do not, e.g. by converting 1+2 into 3.
8668 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8669 renames Fully_Conformant_Expressions;
8671 function FCL (L1, L2 : List_Id) return Boolean;
8672 -- Compare elements of two lists for conformance. Elements have to be
8673 -- conformant, and actuals inserted as default parameters do not match
8674 -- explicit actuals with the same value.
8676 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8677 -- Compare an operator node with a function call
8683 function FCL (L1, L2 : List_Id) return Boolean is
8687 if L1 = No_List then
8693 if L2 = No_List then
8699 -- Compare two lists, skipping rewrite insertions (we want to compare
8700 -- the original trees, not the expanded versions).
8703 if Is_Rewrite_Insertion (N1) then
8705 elsif Is_Rewrite_Insertion (N2) then
8711 elsif not FCE (N1, N2) then
8724 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8725 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8730 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8735 Act := First (Actuals);
8737 if Nkind (Op_Node) in N_Binary_Op then
8738 if not FCE (Left_Opnd (Op_Node), Act) then
8745 return Present (Act)
8746 and then FCE (Right_Opnd (Op_Node), Act)
8747 and then No (Next (Act));
8751 -- Start of processing for Fully_Conformant_Expressions
8754 -- Nonconformant if paren count does not match. Note: if some idiot
8755 -- complains that we don't do this right for more than 3 levels of
8756 -- parentheses, they will be treated with the respect they deserve.
8758 if Paren_Count (E1) /= Paren_Count (E2) then
8761 -- If same entities are referenced, then they are conformant even if
8762 -- they have different forms (RM 8.3.1(19-20)).
8764 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8765 if Present (Entity (E1)) then
8766 return Entity (E1) = Entity (E2)
8768 -- One may be a discriminant that has been replaced by the
8769 -- corresponding discriminal.
8772 (Chars (Entity (E1)) = Chars (Entity (E2))
8773 and then Ekind (Entity (E1)) = E_Discriminant
8774 and then Ekind (Entity (E2)) = E_In_Parameter)
8776 -- The discriminant of a protected type is transformed into
8777 -- a local constant and then into a parameter of a protected
8781 (Ekind (Entity (E1)) = E_Constant
8782 and then Ekind (Entity (E2)) = E_In_Parameter
8783 and then Present (Discriminal_Link (Entity (E1)))
8784 and then Discriminal_Link (Entity (E1)) =
8785 Discriminal_Link (Entity (E2)))
8787 -- AI12-050: The loop variables of quantified expressions
8788 -- match if they have the same identifier, even though they
8789 -- are different entities.
8792 (Chars (Entity (E1)) = Chars (Entity (E2))
8793 and then Ekind (Entity (E1)) = E_Loop_Parameter
8794 and then Ekind (Entity (E2)) = E_Loop_Parameter);
8796 elsif Nkind (E1) = N_Expanded_Name
8797 and then Nkind (E2) = N_Expanded_Name
8798 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8799 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8801 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8804 -- Identifiers in component associations don't always have
8805 -- entities, but their names must conform.
8807 return Nkind (E1) = N_Identifier
8808 and then Nkind (E2) = N_Identifier
8809 and then Chars (E1) = Chars (E2);
8812 elsif Nkind (E1) = N_Character_Literal
8813 and then Nkind (E2) = N_Expanded_Name
8815 return Nkind (Selector_Name (E2)) = N_Character_Literal
8816 and then Chars (E1) = Chars (Selector_Name (E2));
8818 elsif Nkind (E2) = N_Character_Literal
8819 and then Nkind (E1) = N_Expanded_Name
8821 return Nkind (Selector_Name (E1)) = N_Character_Literal
8822 and then Chars (E2) = Chars (Selector_Name (E1));
8824 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8825 return FCO (E1, E2);
8827 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8828 return FCO (E2, E1);
8830 -- Otherwise we must have the same syntactic entity
8832 elsif Nkind (E1) /= Nkind (E2) then
8835 -- At this point, we specialize by node type
8841 FCL (Expressions (E1), Expressions (E2))
8843 FCL (Component_Associations (E1),
8844 Component_Associations (E2));
8847 if Nkind (Expression (E1)) = N_Qualified_Expression
8849 Nkind (Expression (E2)) = N_Qualified_Expression
8851 return FCE (Expression (E1), Expression (E2));
8853 -- Check that the subtype marks and any constraints
8858 Indic1 : constant Node_Id := Expression (E1);
8859 Indic2 : constant Node_Id := Expression (E2);
8864 if Nkind (Indic1) /= N_Subtype_Indication then
8866 Nkind (Indic2) /= N_Subtype_Indication
8867 and then Entity (Indic1) = Entity (Indic2);
8869 elsif Nkind (Indic2) /= N_Subtype_Indication then
8871 Nkind (Indic1) /= N_Subtype_Indication
8872 and then Entity (Indic1) = Entity (Indic2);
8875 if Entity (Subtype_Mark (Indic1)) /=
8876 Entity (Subtype_Mark (Indic2))
8881 Elt1 := First (Constraints (Constraint (Indic1)));
8882 Elt2 := First (Constraints (Constraint (Indic2)));
8883 while Present (Elt1) and then Present (Elt2) loop
8884 if not FCE (Elt1, Elt2) then
8897 when N_Attribute_Reference =>
8899 Attribute_Name (E1) = Attribute_Name (E2)
8900 and then FCL (Expressions (E1), Expressions (E2));
8904 Entity (E1) = Entity (E2)
8905 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
8906 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
8908 when N_Membership_Test
8912 FCE (Left_Opnd (E1), Left_Opnd (E2))
8914 FCE (Right_Opnd (E1), Right_Opnd (E2));
8916 when N_Case_Expression =>
8922 if not FCE (Expression (E1), Expression (E2)) then
8926 Alt1 := First (Alternatives (E1));
8927 Alt2 := First (Alternatives (E2));
8929 if Present (Alt1) /= Present (Alt2) then
8931 elsif No (Alt1) then
8935 if not FCE (Expression (Alt1), Expression (Alt2))
8936 or else not FCL (Discrete_Choices (Alt1),
8937 Discrete_Choices (Alt2))
8948 when N_Character_Literal =>
8950 Char_Literal_Value (E1) = Char_Literal_Value (E2);
8952 when N_Component_Association =>
8954 FCL (Choices (E1), Choices (E2))
8956 FCE (Expression (E1), Expression (E2));
8958 when N_Explicit_Dereference =>
8960 FCE (Prefix (E1), Prefix (E2));
8962 when N_Extension_Aggregate =>
8964 FCL (Expressions (E1), Expressions (E2))
8965 and then Null_Record_Present (E1) =
8966 Null_Record_Present (E2)
8967 and then FCL (Component_Associations (E1),
8968 Component_Associations (E2));
8970 when N_Function_Call =>
8972 FCE (Name (E1), Name (E2))
8974 FCL (Parameter_Associations (E1),
8975 Parameter_Associations (E2));
8977 when N_If_Expression =>
8979 FCL (Expressions (E1), Expressions (E2));
8981 when N_Indexed_Component =>
8983 FCE (Prefix (E1), Prefix (E2))
8985 FCL (Expressions (E1), Expressions (E2));
8987 when N_Integer_Literal =>
8988 return (Intval (E1) = Intval (E2));
8993 when N_Operator_Symbol =>
8995 Chars (E1) = Chars (E2);
8997 when N_Others_Choice =>
9000 when N_Parameter_Association =>
9002 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9003 and then FCE (Explicit_Actual_Parameter (E1),
9004 Explicit_Actual_Parameter (E2));
9006 when N_Qualified_Expression
9008 | N_Unchecked_Type_Conversion
9011 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9013 FCE (Expression (E1), Expression (E2));
9015 when N_Quantified_Expression =>
9016 if not FCE (Condition (E1), Condition (E2)) then
9020 if Present (Loop_Parameter_Specification (E1))
9021 and then Present (Loop_Parameter_Specification (E2))
9024 L1 : constant Node_Id :=
9025 Loop_Parameter_Specification (E1);
9026 L2 : constant Node_Id :=
9027 Loop_Parameter_Specification (E2);
9031 Reverse_Present (L1) = Reverse_Present (L2)
9033 FCE (Defining_Identifier (L1),
9034 Defining_Identifier (L2))
9036 FCE (Discrete_Subtype_Definition (L1),
9037 Discrete_Subtype_Definition (L2));
9040 elsif Present (Iterator_Specification (E1))
9041 and then Present (Iterator_Specification (E2))
9044 I1 : constant Node_Id := Iterator_Specification (E1);
9045 I2 : constant Node_Id := Iterator_Specification (E2);
9049 FCE (Defining_Identifier (I1),
9050 Defining_Identifier (I2))
9052 Of_Present (I1) = Of_Present (I2)
9054 Reverse_Present (I1) = Reverse_Present (I2)
9055 and then FCE (Name (I1), Name (I2))
9056 and then FCE (Subtype_Indication (I1),
9057 Subtype_Indication (I2));
9060 -- The quantified expressions used different specifications to
9061 -- walk their respective ranges.
9069 FCE (Low_Bound (E1), Low_Bound (E2))
9071 FCE (High_Bound (E1), High_Bound (E2));
9073 when N_Real_Literal =>
9074 return (Realval (E1) = Realval (E2));
9076 when N_Selected_Component =>
9078 FCE (Prefix (E1), Prefix (E2))
9080 FCE (Selector_Name (E1), Selector_Name (E2));
9084 FCE (Prefix (E1), Prefix (E2))
9086 FCE (Discrete_Range (E1), Discrete_Range (E2));
9088 when N_String_Literal =>
9090 S1 : constant String_Id := Strval (E1);
9091 S2 : constant String_Id := Strval (E2);
9092 L1 : constant Nat := String_Length (S1);
9093 L2 : constant Nat := String_Length (S2);
9100 for J in 1 .. L1 loop
9101 if Get_String_Char (S1, J) /=
9102 Get_String_Char (S2, J)
9114 Entity (E1) = Entity (E2)
9116 FCE (Right_Opnd (E1), Right_Opnd (E2));
9118 -- All other node types cannot appear in this context. Strictly
9119 -- we should raise a fatal internal error. Instead we just ignore
9120 -- the nodes. This means that if anyone makes a mistake in the
9121 -- expander and mucks an expression tree irretrievably, the result
9122 -- will be a failure to detect a (probably very obscure) case
9123 -- of non-conformance, which is better than bombing on some
9124 -- case where two expressions do in fact conform.
9130 end Fully_Conformant_Expressions;
9132 ----------------------------------------
9133 -- Fully_Conformant_Discrete_Subtypes --
9134 ----------------------------------------
9136 function Fully_Conformant_Discrete_Subtypes
9137 (Given_S1 : Node_Id;
9138 Given_S2 : Node_Id) return Boolean
9140 S1 : constant Node_Id := Original_Node (Given_S1);
9141 S2 : constant Node_Id := Original_Node (Given_S2);
9143 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9144 -- Special-case for a bound given by a discriminant, which in the body
9145 -- is replaced with the discriminal of the enclosing type.
9147 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9148 -- Check both bounds
9150 -----------------------
9151 -- Conforming_Bounds --
9152 -----------------------
9154 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9156 if Is_Entity_Name (B1)
9157 and then Is_Entity_Name (B2)
9158 and then Ekind (Entity (B1)) = E_Discriminant
9160 return Chars (B1) = Chars (B2);
9163 return Fully_Conformant_Expressions (B1, B2);
9165 end Conforming_Bounds;
9167 -----------------------
9168 -- Conforming_Ranges --
9169 -----------------------
9171 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9174 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9176 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9177 end Conforming_Ranges;
9179 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9182 if Nkind (S1) /= Nkind (S2) then
9185 elsif Is_Entity_Name (S1) then
9186 return Entity (S1) = Entity (S2);
9188 elsif Nkind (S1) = N_Range then
9189 return Conforming_Ranges (S1, S2);
9191 elsif Nkind (S1) = N_Subtype_Indication then
9193 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9196 (Range_Expression (Constraint (S1)),
9197 Range_Expression (Constraint (S2)));
9201 end Fully_Conformant_Discrete_Subtypes;
9203 --------------------
9204 -- Install_Entity --
9205 --------------------
9207 procedure Install_Entity (E : Entity_Id) is
9208 Prev : constant Entity_Id := Current_Entity (E);
9210 Set_Is_Immediately_Visible (E);
9211 Set_Current_Entity (E);
9212 Set_Homonym (E, Prev);
9215 ---------------------
9216 -- Install_Formals --
9217 ---------------------
9219 procedure Install_Formals (Id : Entity_Id) is
9222 F := First_Formal (Id);
9223 while Present (F) loop
9227 end Install_Formals;
9229 -----------------------------
9230 -- Is_Interface_Conformant --
9231 -----------------------------
9233 function Is_Interface_Conformant
9234 (Tagged_Type : Entity_Id;
9235 Iface_Prim : Entity_Id;
9236 Prim : Entity_Id) return Boolean
9238 -- The operation may in fact be an inherited (implicit) operation
9239 -- rather than the original interface primitive, so retrieve the
9240 -- ultimate ancestor.
9242 Iface : constant Entity_Id :=
9243 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9244 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9246 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9247 -- Return the controlling formal of Prim
9249 ------------------------
9250 -- Controlling_Formal --
9251 ------------------------
9253 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9257 E := First_Entity (Prim);
9258 while Present (E) loop
9259 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9267 end Controlling_Formal;
9271 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9272 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9274 -- Start of processing for Is_Interface_Conformant
9277 pragma Assert (Is_Subprogram (Iface_Prim)
9278 and then Is_Subprogram (Prim)
9279 and then Is_Dispatching_Operation (Iface_Prim)
9280 and then Is_Dispatching_Operation (Prim));
9282 pragma Assert (Is_Interface (Iface)
9283 or else (Present (Alias (Iface_Prim))
9286 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9288 if Prim = Iface_Prim
9289 or else not Is_Subprogram (Prim)
9290 or else Ekind (Prim) /= Ekind (Iface_Prim)
9291 or else not Is_Dispatching_Operation (Prim)
9292 or else Scope (Prim) /= Scope (Tagged_Type)
9294 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9295 or else not Primitive_Names_Match (Iface_Prim, Prim)
9299 -- The mode of the controlling formals must match
9301 elsif Present (Iface_Ctrl_F)
9302 and then Present (Prim_Ctrl_F)
9303 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9307 -- Case of a procedure, or a function whose result type matches the
9308 -- result type of the interface primitive, or a function that has no
9309 -- controlling result (I or access I).
9311 elsif Ekind (Iface_Prim) = E_Procedure
9312 or else Etype (Prim) = Etype (Iface_Prim)
9313 or else not Has_Controlling_Result (Prim)
9315 return Type_Conformant
9316 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9318 -- Case of a function returning an interface, or an access to one. Check
9319 -- that the return types correspond.
9321 elsif Implements_Interface (Typ, Iface) then
9322 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9324 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9329 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9330 Skip_Controlling_Formals => True);
9336 end Is_Interface_Conformant;
9338 ---------------------------------
9339 -- Is_Non_Overriding_Operation --
9340 ---------------------------------
9342 function Is_Non_Overriding_Operation
9343 (Prev_E : Entity_Id;
9344 New_E : Entity_Id) return Boolean
9348 G_Typ : Entity_Id := Empty;
9350 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9351 -- If F_Type is a derived type associated with a generic actual subtype,
9352 -- then return its Generic_Parent_Type attribute, else return Empty.
9354 function Types_Correspond
9355 (P_Type : Entity_Id;
9356 N_Type : Entity_Id) return Boolean;
9357 -- Returns true if and only if the types (or designated types in the
9358 -- case of anonymous access types) are the same or N_Type is derived
9359 -- directly or indirectly from P_Type.
9361 -----------------------------
9362 -- Get_Generic_Parent_Type --
9363 -----------------------------
9365 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9371 if Is_Derived_Type (F_Typ)
9372 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9374 -- The tree must be traversed to determine the parent subtype in
9375 -- the generic unit, which unfortunately isn't always available
9376 -- via semantic attributes. ??? (Note: The use of Original_Node
9377 -- is needed for cases where a full derived type has been
9380 -- If the parent type is a scalar type, the derivation creates
9381 -- an anonymous base type for it, and the source type is its
9384 if Is_Scalar_Type (F_Typ)
9385 and then not Comes_From_Source (F_Typ)
9389 (Original_Node (Parent (First_Subtype (F_Typ))));
9391 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9393 if Nkind (Defn) = N_Derived_Type_Definition then
9394 Indic := Subtype_Indication (Defn);
9396 if Nkind (Indic) = N_Subtype_Indication then
9397 G_Typ := Entity (Subtype_Mark (Indic));
9399 G_Typ := Entity (Indic);
9402 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9403 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9405 return Generic_Parent_Type (Parent (G_Typ));
9411 end Get_Generic_Parent_Type;
9413 ----------------------
9414 -- Types_Correspond --
9415 ----------------------
9417 function Types_Correspond
9418 (P_Type : Entity_Id;
9419 N_Type : Entity_Id) return Boolean
9421 Prev_Type : Entity_Id := Base_Type (P_Type);
9422 New_Type : Entity_Id := Base_Type (N_Type);
9425 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9426 Prev_Type := Designated_Type (Prev_Type);
9429 if Ekind (New_Type) = E_Anonymous_Access_Type then
9430 New_Type := Designated_Type (New_Type);
9433 if Prev_Type = New_Type then
9436 elsif not Is_Class_Wide_Type (New_Type) then
9437 while Etype (New_Type) /= New_Type loop
9438 New_Type := Etype (New_Type);
9440 if New_Type = Prev_Type then
9446 end Types_Correspond;
9448 -- Start of processing for Is_Non_Overriding_Operation
9451 -- In the case where both operations are implicit derived subprograms
9452 -- then neither overrides the other. This can only occur in certain
9453 -- obscure cases (e.g., derivation from homographs created in a generic
9456 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9459 elsif Ekind (Current_Scope) = E_Package
9460 and then Is_Generic_Instance (Current_Scope)
9461 and then In_Private_Part (Current_Scope)
9462 and then Comes_From_Source (New_E)
9464 -- We examine the formals and result type of the inherited operation,
9465 -- to determine whether their type is derived from (the instance of)
9466 -- a generic type. The first such formal or result type is the one
9469 Formal := First_Formal (Prev_E);
9471 while Present (Formal) loop
9472 F_Typ := Base_Type (Etype (Formal));
9474 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9475 F_Typ := Designated_Type (F_Typ);
9478 G_Typ := Get_Generic_Parent_Type (F_Typ);
9479 exit when Present (G_Typ);
9481 Next_Formal (Formal);
9484 -- If the function dispatches on result check the result type
9486 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9487 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9494 -- If the generic type is a private type, then the original operation
9495 -- was not overriding in the generic, because there was no primitive
9496 -- operation to override.
9498 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9499 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9500 N_Formal_Private_Type_Definition
9504 -- The generic parent type is the ancestor of a formal derived
9505 -- type declaration. We need to check whether it has a primitive
9506 -- operation that should be overridden by New_E in the generic.
9510 P_Formal : Entity_Id;
9511 N_Formal : Entity_Id;
9515 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9518 while Present (Prim_Elt) loop
9519 P_Prim := Node (Prim_Elt);
9521 if Chars (P_Prim) = Chars (New_E)
9522 and then Ekind (P_Prim) = Ekind (New_E)
9524 P_Formal := First_Formal (P_Prim);
9525 N_Formal := First_Formal (New_E);
9526 while Present (P_Formal) and then Present (N_Formal) loop
9527 P_Typ := Etype (P_Formal);
9528 N_Typ := Etype (N_Formal);
9530 if not Types_Correspond (P_Typ, N_Typ) then
9534 Next_Entity (P_Formal);
9535 Next_Entity (N_Formal);
9538 -- Found a matching primitive operation belonging to the
9539 -- formal ancestor type, so the new subprogram is
9543 and then No (N_Formal)
9544 and then (Ekind (New_E) /= E_Function
9547 (Etype (P_Prim), Etype (New_E)))
9553 Next_Elmt (Prim_Elt);
9556 -- If no match found, then the new subprogram does not override
9557 -- in the generic (nor in the instance).
9559 -- If the type in question is not abstract, and the subprogram
9560 -- is, this will be an error if the new operation is in the
9561 -- private part of the instance. Emit a warning now, which will
9562 -- make the subsequent error message easier to understand.
9564 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9565 and then Is_Abstract_Subprogram (Prev_E)
9566 and then In_Private_Part (Current_Scope)
9568 Error_Msg_Node_2 := F_Typ;
9570 ("private operation& in generic unit does not override "
9571 & "any primitive operation of& (RM 12.3 (18))??",
9581 end Is_Non_Overriding_Operation;
9583 -------------------------------------
9584 -- List_Inherited_Pre_Post_Aspects --
9585 -------------------------------------
9587 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9589 if Opt.List_Inherited_Aspects
9590 and then Is_Subprogram_Or_Generic_Subprogram (E)
9593 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9598 for Index in Subps'Range loop
9599 Items := Contract (Subps (Index));
9601 if Present (Items) then
9602 Prag := Pre_Post_Conditions (Items);
9603 while Present (Prag) loop
9604 Error_Msg_Sloc := Sloc (Prag);
9606 if Class_Present (Prag)
9607 and then not Split_PPC (Prag)
9609 if Pragma_Name (Prag) = Name_Precondition then
9611 ("info: & inherits `Pre''Class` aspect from "
9615 ("info: & inherits `Post''Class` aspect from "
9620 Prag := Next_Pragma (Prag);
9626 end List_Inherited_Pre_Post_Aspects;
9628 ------------------------------
9629 -- Make_Inequality_Operator --
9630 ------------------------------
9632 -- S is the defining identifier of an equality operator. We build a
9633 -- subprogram declaration with the right signature. This operation is
9634 -- intrinsic, because it is always expanded as the negation of the
9635 -- call to the equality function.
9637 procedure Make_Inequality_Operator (S : Entity_Id) is
9638 Loc : constant Source_Ptr := Sloc (S);
9641 Op_Name : Entity_Id;
9643 FF : constant Entity_Id := First_Formal (S);
9644 NF : constant Entity_Id := Next_Formal (FF);
9647 -- Check that equality was properly defined, ignore call if not
9654 A : constant Entity_Id :=
9655 Make_Defining_Identifier (Sloc (FF),
9656 Chars => Chars (FF));
9658 B : constant Entity_Id :=
9659 Make_Defining_Identifier (Sloc (NF),
9660 Chars => Chars (NF));
9663 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9665 Formals := New_List (
9666 Make_Parameter_Specification (Loc,
9667 Defining_Identifier => A,
9669 New_Occurrence_Of (Etype (First_Formal (S)),
9670 Sloc (Etype (First_Formal (S))))),
9672 Make_Parameter_Specification (Loc,
9673 Defining_Identifier => B,
9675 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9676 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9679 Make_Subprogram_Declaration (Loc,
9681 Make_Function_Specification (Loc,
9682 Defining_Unit_Name => Op_Name,
9683 Parameter_Specifications => Formals,
9684 Result_Definition =>
9685 New_Occurrence_Of (Standard_Boolean, Loc)));
9687 -- Insert inequality right after equality if it is explicit or after
9688 -- the derived type when implicit. These entities are created only
9689 -- for visibility purposes, and eventually replaced in the course
9690 -- of expansion, so they do not need to be attached to the tree and
9691 -- seen by the back-end. Keeping them internal also avoids spurious
9692 -- freezing problems. The declaration is inserted in the tree for
9693 -- analysis, and removed afterwards. If the equality operator comes
9694 -- from an explicit declaration, attach the inequality immediately
9695 -- after. Else the equality is inherited from a derived type
9696 -- declaration, so insert inequality after that declaration.
9698 if No (Alias (S)) then
9699 Insert_After (Unit_Declaration_Node (S), Decl);
9700 elsif Is_List_Member (Parent (S)) then
9701 Insert_After (Parent (S), Decl);
9703 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9706 Mark_Rewrite_Insertion (Decl);
9707 Set_Is_Intrinsic_Subprogram (Op_Name);
9710 Set_Has_Completion (Op_Name);
9711 Set_Corresponding_Equality (Op_Name, S);
9712 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9714 end Make_Inequality_Operator;
9716 ----------------------
9717 -- May_Need_Actuals --
9718 ----------------------
9720 procedure May_Need_Actuals (Fun : Entity_Id) is
9725 F := First_Formal (Fun);
9727 while Present (F) loop
9728 if No (Default_Value (F)) then
9736 Set_Needs_No_Actuals (Fun, B);
9737 end May_Need_Actuals;
9739 ---------------------
9740 -- Mode_Conformant --
9741 ---------------------
9743 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9746 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9748 end Mode_Conformant;
9750 ---------------------------
9751 -- New_Overloaded_Entity --
9752 ---------------------------
9754 procedure New_Overloaded_Entity
9756 Derived_Type : Entity_Id := Empty)
9758 Overridden_Subp : Entity_Id := Empty;
9759 -- Set if the current scope has an operation that is type-conformant
9760 -- with S, and becomes hidden by S.
9762 Is_Primitive_Subp : Boolean;
9763 -- Set to True if the new subprogram is primitive
9766 -- Entity that S overrides
9768 Prev_Vis : Entity_Id := Empty;
9769 -- Predecessor of E in Homonym chain
9771 procedure Check_For_Primitive_Subprogram
9772 (Is_Primitive : out Boolean;
9773 Is_Overriding : Boolean := False);
9774 -- If the subprogram being analyzed is a primitive operation of the type
9775 -- of a formal or result, set the Has_Primitive_Operations flag on the
9776 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9777 -- corresponding flag on the entity itself for later use.
9779 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9780 -- True if a) E is a subprogram whose first formal is a concurrent type
9781 -- defined in the scope of E that has some entry or subprogram whose
9782 -- profile matches E, or b) E is an internally built dispatching
9783 -- subprogram of a protected type and there is a matching subprogram
9784 -- defined in the enclosing scope of the protected type, or c) E is
9785 -- an entry of a synchronized type and a matching procedure has been
9786 -- previously defined in the enclosing scope of the synchronized type.
9788 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9789 -- Check that E is declared in the private part of the current package,
9790 -- or in the package body, where it may hide a previous declaration.
9791 -- We can't use In_Private_Part by itself because this flag is also
9792 -- set when freezing entities, so we must examine the place of the
9793 -- declaration in the tree, and recognize wrapper packages as well.
9795 function Is_Overriding_Alias
9797 New_E : Entity_Id) return Boolean;
9798 -- Check whether new subprogram and old subprogram are both inherited
9799 -- from subprograms that have distinct dispatch table entries. This can
9800 -- occur with derivations from instances with accidental homonyms. The
9801 -- function is conservative given that the converse is only true within
9802 -- instances that contain accidental overloadings.
9804 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9805 -- Report conflict between entities S and E
9807 ------------------------------------
9808 -- Check_For_Primitive_Subprogram --
9809 ------------------------------------
9811 procedure Check_For_Primitive_Subprogram
9812 (Is_Primitive : out Boolean;
9813 Is_Overriding : Boolean := False)
9819 function Visible_Part_Type (T : Entity_Id) return Boolean;
9820 -- Returns true if T is declared in the visible part of the current
9821 -- package scope; otherwise returns false. Assumes that T is declared
9824 procedure Check_Private_Overriding (T : Entity_Id);
9825 -- Checks that if a primitive abstract subprogram of a visible
9826 -- abstract type is declared in a private part, then it must override
9827 -- an abstract subprogram declared in the visible part. Also checks
9828 -- that if a primitive function with a controlling result is declared
9829 -- in a private part, then it must override a function declared in
9830 -- the visible part.
9832 ------------------------------
9833 -- Check_Private_Overriding --
9834 ------------------------------
9836 procedure Check_Private_Overriding (T : Entity_Id) is
9837 function Overrides_Private_Part_Op return Boolean;
9838 -- This detects the special case where the overriding subprogram
9839 -- is overriding a subprogram that was declared in the same
9840 -- private part. That case is illegal by 3.9.3(10).
9842 function Overrides_Visible_Function
9843 (Partial_View : Entity_Id) return Boolean;
9844 -- True if S overrides a function in the visible part. The
9845 -- overridden function could be explicitly or implicitly declared.
9847 -------------------------------
9848 -- Overrides_Private_Part_Op --
9849 -------------------------------
9851 function Overrides_Private_Part_Op return Boolean is
9852 Over_Decl : constant Node_Id :=
9853 Unit_Declaration_Node (Overridden_Operation (S));
9854 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
9857 pragma Assert (Is_Overriding);
9859 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
9861 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
9863 return In_Same_List (Over_Decl, Subp_Decl);
9864 end Overrides_Private_Part_Op;
9866 --------------------------------
9867 -- Overrides_Visible_Function --
9868 --------------------------------
9870 function Overrides_Visible_Function
9871 (Partial_View : Entity_Id) return Boolean
9874 if not Is_Overriding or else not Has_Homonym (S) then
9878 if not Present (Partial_View) then
9882 -- Search through all the homonyms H of S in the current
9883 -- package spec, and return True if we find one that matches.
9884 -- Note that Parent (H) will be the declaration of the
9885 -- partial view of T for a match.
9892 exit when not Present (H) or else Scope (H) /= Scope (S);
9896 N_Private_Extension_Declaration,
9897 N_Private_Type_Declaration)
9898 and then Defining_Identifier (Parent (H)) = Partial_View
9906 end Overrides_Visible_Function;
9908 -- Start of processing for Check_Private_Overriding
9911 if Is_Package_Or_Generic_Package (Current_Scope)
9912 and then In_Private_Part (Current_Scope)
9913 and then Visible_Part_Type (T)
9914 and then not In_Instance
9916 if Is_Abstract_Type (T)
9917 and then Is_Abstract_Subprogram (S)
9918 and then (not Is_Overriding
9919 or else not Is_Abstract_Subprogram (E)
9920 or else Overrides_Private_Part_Op)
9923 ("abstract subprograms must be visible (RM 3.9.3(10))!",
9926 elsif Ekind (S) = E_Function then
9928 Partial_View : constant Entity_Id :=
9929 Incomplete_Or_Partial_View (T);
9932 if not Overrides_Visible_Function (Partial_View) then
9934 -- Here, S is "function ... return T;" declared in
9935 -- the private part, not overriding some visible
9936 -- operation. That's illegal in the tagged case
9937 -- (but not if the private type is untagged).
9939 if ((Present (Partial_View)
9940 and then Is_Tagged_Type (Partial_View))
9941 or else (not Present (Partial_View)
9942 and then Is_Tagged_Type (T)))
9943 and then T = Base_Type (Etype (S))
9946 ("private function with tagged result must"
9947 & " override visible-part function", S);
9949 ("\move subprogram to the visible part"
9950 & " (RM 3.9.3(10))", S);
9952 -- AI05-0073: extend this test to the case of a
9953 -- function with a controlling access result.
9955 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
9956 and then Is_Tagged_Type (Designated_Type (Etype (S)))
9958 not Is_Class_Wide_Type
9959 (Designated_Type (Etype (S)))
9960 and then Ada_Version >= Ada_2012
9963 ("private function with controlling access "
9964 & "result must override visible-part function",
9967 ("\move subprogram to the visible part"
9968 & " (RM 3.9.3(10))", S);
9974 end Check_Private_Overriding;
9976 -----------------------
9977 -- Visible_Part_Type --
9978 -----------------------
9980 function Visible_Part_Type (T : Entity_Id) return Boolean is
9981 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
9985 -- If the entity is a private type, then it must be declared in a
9988 if Ekind (T) in Private_Kind then
9992 -- Otherwise, we traverse the visible part looking for its
9993 -- corresponding declaration. We cannot use the declaration
9994 -- node directly because in the private part the entity of a
9995 -- private type is the one in the full view, which does not
9996 -- indicate that it is the completion of something visible.
9998 N := First (Visible_Declarations (Specification (P)));
9999 while Present (N) loop
10000 if Nkind (N) = N_Full_Type_Declaration
10001 and then Present (Defining_Identifier (N))
10002 and then T = Defining_Identifier (N)
10006 elsif Nkind_In (N, N_Private_Type_Declaration,
10007 N_Private_Extension_Declaration)
10008 and then Present (Defining_Identifier (N))
10009 and then T = Full_View (Defining_Identifier (N))
10018 end Visible_Part_Type;
10020 -- Start of processing for Check_For_Primitive_Subprogram
10023 Is_Primitive := False;
10025 if not Comes_From_Source (S) then
10028 -- If subprogram is at library level, it is not primitive operation
10030 elsif Current_Scope = Standard_Standard then
10033 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10034 and then not In_Package_Body (Current_Scope))
10035 or else Is_Overriding
10037 -- For function, check return type
10039 if Ekind (S) = E_Function then
10040 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10041 F_Typ := Designated_Type (Etype (S));
10043 F_Typ := Etype (S);
10046 B_Typ := Base_Type (F_Typ);
10048 if Scope (B_Typ) = Current_Scope
10049 and then not Is_Class_Wide_Type (B_Typ)
10050 and then not Is_Generic_Type (B_Typ)
10052 Is_Primitive := True;
10053 Set_Has_Primitive_Operations (B_Typ);
10054 Set_Is_Primitive (S);
10055 Check_Private_Overriding (B_Typ);
10057 -- The Ghost policy in effect at the point of declaration
10058 -- or a tagged type and a primitive operation must match
10059 -- (SPARK RM 6.9(16)).
10061 Check_Ghost_Primitive (S, B_Typ);
10065 -- For all subprograms, check formals
10067 Formal := First_Formal (S);
10068 while Present (Formal) loop
10069 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10070 F_Typ := Designated_Type (Etype (Formal));
10072 F_Typ := Etype (Formal);
10075 B_Typ := Base_Type (F_Typ);
10077 if Ekind (B_Typ) = E_Access_Subtype then
10078 B_Typ := Base_Type (B_Typ);
10081 if Scope (B_Typ) = Current_Scope
10082 and then not Is_Class_Wide_Type (B_Typ)
10083 and then not Is_Generic_Type (B_Typ)
10085 Is_Primitive := True;
10086 Set_Is_Primitive (S);
10087 Set_Has_Primitive_Operations (B_Typ);
10088 Check_Private_Overriding (B_Typ);
10090 -- The Ghost policy in effect at the point of declaration
10091 -- of a tagged type and a primitive operation must match
10092 -- (SPARK RM 6.9(16)).
10094 Check_Ghost_Primitive (S, B_Typ);
10097 Next_Formal (Formal);
10100 -- Special case: An equality function can be redefined for a type
10101 -- occurring in a declarative part, and won't otherwise be treated as
10102 -- a primitive because it doesn't occur in a package spec and doesn't
10103 -- override an inherited subprogram. It's important that we mark it
10104 -- primitive so it can be returned by Collect_Primitive_Operations
10105 -- and be used in composing the equality operation of later types
10106 -- that have a component of the type.
10108 elsif Chars (S) = Name_Op_Eq
10109 and then Etype (S) = Standard_Boolean
10111 B_Typ := Base_Type (Etype (First_Formal (S)));
10113 if Scope (B_Typ) = Current_Scope
10115 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10116 and then not Is_Limited_Type (B_Typ)
10118 Is_Primitive := True;
10119 Set_Is_Primitive (S);
10120 Set_Has_Primitive_Operations (B_Typ);
10121 Check_Private_Overriding (B_Typ);
10123 -- The Ghost policy in effect at the point of declaration of a
10124 -- tagged type and a primitive operation must match
10125 -- (SPARK RM 6.9(16)).
10127 Check_Ghost_Primitive (S, B_Typ);
10130 end Check_For_Primitive_Subprogram;
10132 --------------------------------------
10133 -- Has_Matching_Entry_Or_Subprogram --
10134 --------------------------------------
10136 function Has_Matching_Entry_Or_Subprogram
10137 (E : Entity_Id) return Boolean
10139 function Check_Conforming_Parameters
10140 (E1_Param : Node_Id;
10141 E2_Param : Node_Id) return Boolean;
10142 -- Starting from the given parameters, check that all the parameters
10143 -- of two entries or subprograms are subtype conformant. Used to skip
10144 -- the check on the controlling argument.
10146 function Matching_Entry_Or_Subprogram
10147 (Conc_Typ : Entity_Id;
10148 Subp : Entity_Id) return Entity_Id;
10149 -- Return the first entry or subprogram of the given concurrent type
10150 -- whose name matches the name of Subp and has a profile conformant
10151 -- with Subp; return Empty if not found.
10153 function Matching_Dispatching_Subprogram
10154 (Conc_Typ : Entity_Id;
10155 Ent : Entity_Id) return Entity_Id;
10156 -- Return the first dispatching primitive of Conc_Type defined in the
10157 -- enclosing scope of Conc_Type (i.e. before the full definition of
10158 -- this concurrent type) whose name matches the entry Ent and has a
10159 -- profile conformant with the profile of the corresponding (not yet
10160 -- built) dispatching primitive of Ent; return Empty if not found.
10162 function Matching_Original_Protected_Subprogram
10163 (Prot_Typ : Entity_Id;
10164 Subp : Entity_Id) return Entity_Id;
10165 -- Return the first subprogram defined in the enclosing scope of
10166 -- Prot_Typ (before the full definition of this protected type)
10167 -- whose name matches the original name of Subp and has a profile
10168 -- conformant with the profile of Subp; return Empty if not found.
10170 ---------------------------------
10171 -- Check_Confirming_Parameters --
10172 ---------------------------------
10174 function Check_Conforming_Parameters
10175 (E1_Param : Node_Id;
10176 E2_Param : Node_Id) return Boolean
10178 Param_E1 : Node_Id := E1_Param;
10179 Param_E2 : Node_Id := E2_Param;
10182 while Present (Param_E1) and then Present (Param_E2) loop
10183 if Ekind (Defining_Identifier (Param_E1)) /=
10184 Ekind (Defining_Identifier (Param_E2))
10187 (Find_Parameter_Type (Param_E1),
10188 Find_Parameter_Type (Param_E2),
10189 Subtype_Conformant)
10198 -- The candidate is not valid if one of the two lists contains
10199 -- more parameters than the other
10201 return No (Param_E1) and then No (Param_E2);
10202 end Check_Conforming_Parameters;
10204 ----------------------------------
10205 -- Matching_Entry_Or_Subprogram --
10206 ----------------------------------
10208 function Matching_Entry_Or_Subprogram
10209 (Conc_Typ : Entity_Id;
10210 Subp : Entity_Id) return Entity_Id
10215 E := First_Entity (Conc_Typ);
10216 while Present (E) loop
10217 if Chars (Subp) = Chars (E)
10218 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10220 Check_Conforming_Parameters
10221 (First (Parameter_Specifications (Parent (E))),
10222 Next (First (Parameter_Specifications (Parent (Subp)))))
10231 end Matching_Entry_Or_Subprogram;
10233 -------------------------------------
10234 -- Matching_Dispatching_Subprogram --
10235 -------------------------------------
10237 function Matching_Dispatching_Subprogram
10238 (Conc_Typ : Entity_Id;
10239 Ent : Entity_Id) return Entity_Id
10244 -- Search for entities in the enclosing scope of this synchonized
10247 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10248 Push_Scope (Scope (Conc_Typ));
10249 E := Current_Entity_In_Scope (Ent);
10252 while Present (E) loop
10253 if Scope (E) = Scope (Conc_Typ)
10254 and then Comes_From_Source (E)
10255 and then Ekind (E) = E_Procedure
10256 and then Present (First_Entity (E))
10257 and then Is_Controlling_Formal (First_Entity (E))
10258 and then Etype (First_Entity (E)) = Conc_Typ
10260 Check_Conforming_Parameters
10261 (First (Parameter_Specifications (Parent (Ent))),
10262 Next (First (Parameter_Specifications (Parent (E)))))
10271 end Matching_Dispatching_Subprogram;
10273 --------------------------------------------
10274 -- Matching_Original_Protected_Subprogram --
10275 --------------------------------------------
10277 function Matching_Original_Protected_Subprogram
10278 (Prot_Typ : Entity_Id;
10279 Subp : Entity_Id) return Entity_Id
10281 ICF : constant Boolean :=
10282 Is_Controlling_Formal (First_Entity (Subp));
10286 -- Temporarily decorate the first parameter of Subp as controlling
10287 -- formal, required to invoke Subtype_Conformant.
10289 Set_Is_Controlling_Formal (First_Entity (Subp));
10292 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10294 while Present (E) loop
10295 if Scope (E) = Scope (Prot_Typ)
10296 and then Comes_From_Source (E)
10297 and then Ekind (Subp) = Ekind (E)
10298 and then Present (First_Entity (E))
10299 and then Is_Controlling_Formal (First_Entity (E))
10300 and then Etype (First_Entity (E)) = Prot_Typ
10301 and then Subtype_Conformant (Subp, E,
10302 Skip_Controlling_Formals => True)
10304 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10311 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10314 end Matching_Original_Protected_Subprogram;
10316 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10319 -- Case 1: E is a subprogram whose first formal is a concurrent type
10320 -- defined in the scope of E that has an entry or subprogram whose
10321 -- profile matches E.
10323 if Comes_From_Source (E)
10324 and then Is_Subprogram (E)
10325 and then Present (First_Entity (E))
10326 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10329 Scope (Corresponding_Concurrent_Type
10330 (Etype (First_Entity (E))))
10333 (Matching_Entry_Or_Subprogram
10334 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10337 Report_Conflict (E,
10338 Matching_Entry_Or_Subprogram
10339 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10344 -- Case 2: E is an internally built dispatching subprogram of a
10345 -- protected type and there is a subprogram defined in the enclosing
10346 -- scope of the protected type that has the original name of E and
10347 -- its profile is conformant with the profile of E. We check the
10348 -- name of the original protected subprogram associated with E since
10349 -- the expander builds dispatching primitives of protected functions
10350 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10352 elsif not Comes_From_Source (E)
10353 and then Is_Subprogram (E)
10354 and then Present (First_Entity (E))
10355 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10356 and then Present (Original_Protected_Subprogram (E))
10359 (Matching_Original_Protected_Subprogram
10360 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10363 Report_Conflict (E,
10364 Matching_Original_Protected_Subprogram
10365 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10369 -- Case 3: E is an entry of a synchronized type and a matching
10370 -- procedure has been previously defined in the enclosing scope
10371 -- of the synchronized type.
10373 elsif Comes_From_Source (E)
10374 and then Ekind (E) = E_Entry
10376 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10378 Report_Conflict (E,
10379 Matching_Dispatching_Subprogram (Current_Scope, E));
10384 end Has_Matching_Entry_Or_Subprogram;
10386 ----------------------------
10387 -- Is_Private_Declaration --
10388 ----------------------------
10390 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10391 Decl : constant Node_Id := Unit_Declaration_Node (E);
10392 Priv_Decls : List_Id;
10395 if Is_Package_Or_Generic_Package (Current_Scope)
10396 and then In_Private_Part (Current_Scope)
10399 Private_Declarations (Package_Specification (Current_Scope));
10401 return In_Package_Body (Current_Scope)
10403 (Is_List_Member (Decl)
10404 and then List_Containing (Decl) = Priv_Decls)
10405 or else (Nkind (Parent (Decl)) = N_Package_Specification
10407 Is_Compilation_Unit
10408 (Defining_Entity (Parent (Decl)))
10409 and then List_Containing (Parent (Parent (Decl))) =
10414 end Is_Private_Declaration;
10416 --------------------------
10417 -- Is_Overriding_Alias --
10418 --------------------------
10420 function Is_Overriding_Alias
10421 (Old_E : Entity_Id;
10422 New_E : Entity_Id) return Boolean
10424 AO : constant Entity_Id := Alias (Old_E);
10425 AN : constant Entity_Id := Alias (New_E);
10428 return Scope (AO) /= Scope (AN)
10429 or else No (DTC_Entity (AO))
10430 or else No (DTC_Entity (AN))
10431 or else DT_Position (AO) = DT_Position (AN);
10432 end Is_Overriding_Alias;
10434 ---------------------
10435 -- Report_Conflict --
10436 ---------------------
10438 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10440 Error_Msg_Sloc := Sloc (E);
10442 -- Generate message, with useful additional warning if in generic
10444 if Is_Generic_Unit (E) then
10445 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10446 Error_Msg_N ("\& conflicts with declaration#", S);
10448 Error_Msg_N ("& conflicts with declaration#", S);
10450 end Report_Conflict;
10452 -- Start of processing for New_Overloaded_Entity
10455 -- We need to look for an entity that S may override. This must be a
10456 -- homonym in the current scope, so we look for the first homonym of
10457 -- S in the current scope as the starting point for the search.
10459 E := Current_Entity_In_Scope (S);
10461 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10462 -- They are directly added to the list of primitive operations of
10463 -- Derived_Type, unless this is a rederivation in the private part
10464 -- of an operation that was already derived in the visible part of
10465 -- the current package.
10467 if Ada_Version >= Ada_2005
10468 and then Present (Derived_Type)
10469 and then Present (Alias (S))
10470 and then Is_Dispatching_Operation (Alias (S))
10471 and then Present (Find_Dispatching_Type (Alias (S)))
10472 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10474 -- For private types, when the full-view is processed we propagate to
10475 -- the full view the non-overridden entities whose attribute "alias"
10476 -- references an interface primitive. These entities were added by
10477 -- Derive_Subprograms to ensure that interface primitives are
10480 -- Inside_Freeze_Actions is non zero when S corresponds with an
10481 -- internal entity that links an interface primitive with its
10482 -- covering primitive through attribute Interface_Alias (see
10483 -- Add_Internal_Interface_Entities).
10485 if Inside_Freezing_Actions = 0
10486 and then Is_Package_Or_Generic_Package (Current_Scope)
10487 and then In_Private_Part (Current_Scope)
10488 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10489 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10490 and then Full_View (Defining_Identifier (Parent (E)))
10491 = Defining_Identifier (Parent (S))
10492 and then Alias (E) = Alias (S)
10494 Check_Operation_From_Private_View (S, E);
10495 Set_Is_Dispatching_Operation (S);
10500 Enter_Overloaded_Entity (S);
10501 Check_Dispatching_Operation (S, Empty);
10502 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10508 -- For synchronized types check conflicts of this entity with previously
10509 -- defined entities.
10511 if Ada_Version >= Ada_2005
10512 and then Has_Matching_Entry_Or_Subprogram (S)
10517 -- If there is no homonym then this is definitely not overriding
10520 Enter_Overloaded_Entity (S);
10521 Check_Dispatching_Operation (S, Empty);
10522 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10524 -- If subprogram has an explicit declaration, check whether it has an
10525 -- overriding indicator.
10527 if Comes_From_Source (S) then
10528 Check_Synchronized_Overriding (S, Overridden_Subp);
10530 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10531 -- it may have overridden some hidden inherited primitive. Update
10532 -- Overridden_Subp to avoid spurious errors when checking the
10533 -- overriding indicator.
10535 if Ada_Version >= Ada_2012
10536 and then No (Overridden_Subp)
10537 and then Is_Dispatching_Operation (S)
10538 and then Present (Overridden_Operation (S))
10540 Overridden_Subp := Overridden_Operation (S);
10543 Check_Overriding_Indicator
10544 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10546 -- The Ghost policy in effect at the point of declaration of a
10547 -- parent subprogram and an overriding subprogram must match
10548 -- (SPARK RM 6.9(17)).
10550 Check_Ghost_Overriding (S, Overridden_Subp);
10553 -- If there is a homonym that is not overloadable, then we have an
10554 -- error, except for the special cases checked explicitly below.
10556 elsif not Is_Overloadable (E) then
10558 -- Check for spurious conflict produced by a subprogram that has the
10559 -- same name as that of the enclosing generic package. The conflict
10560 -- occurs within an instance, between the subprogram and the renaming
10561 -- declaration for the package. After the subprogram, the package
10562 -- renaming declaration becomes hidden.
10564 if Ekind (E) = E_Package
10565 and then Present (Renamed_Object (E))
10566 and then Renamed_Object (E) = Current_Scope
10567 and then Nkind (Parent (Renamed_Object (E))) =
10568 N_Package_Specification
10569 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10572 Set_Is_Immediately_Visible (E, False);
10573 Enter_Overloaded_Entity (S);
10574 Set_Homonym (S, Homonym (E));
10575 Check_Dispatching_Operation (S, Empty);
10576 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10578 -- If the subprogram is implicit it is hidden by the previous
10579 -- declaration. However if it is dispatching, it must appear in the
10580 -- dispatch table anyway, because it can be dispatched to even if it
10581 -- cannot be called directly.
10583 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10584 Set_Scope (S, Current_Scope);
10586 if Is_Dispatching_Operation (Alias (S)) then
10587 Check_Dispatching_Operation (S, Empty);
10593 Report_Conflict (S, E);
10597 -- E exists and is overloadable
10600 Check_Synchronized_Overriding (S, Overridden_Subp);
10602 -- Loop through E and its homonyms to determine if any of them is
10603 -- the candidate for overriding by S.
10605 while Present (E) loop
10607 -- Definitely not interesting if not in the current scope
10609 if Scope (E) /= Current_Scope then
10612 -- A function can overload the name of an abstract state. The
10613 -- state can be viewed as a function with a profile that cannot
10614 -- be matched by anything.
10616 elsif Ekind (S) = E_Function
10617 and then Ekind (E) = E_Abstract_State
10619 Enter_Overloaded_Entity (S);
10622 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10623 -- procedures locate the internally generated spec. We enforce
10624 -- mode conformance since a tagged type may inherit from
10625 -- interfaces several null primitives which differ only in
10626 -- the mode of the formals.
10628 elsif not Comes_From_Source (S)
10629 and then Is_Null_Procedure (S)
10630 and then not Mode_Conformant (E, S)
10634 -- Check if we have type conformance
10636 elsif Type_Conformant (E, S) then
10638 -- If the old and new entities have the same profile and one
10639 -- is not the body of the other, then this is an error, unless
10640 -- one of them is implicitly declared.
10642 -- There are some cases when both can be implicit, for example
10643 -- when both a literal and a function that overrides it are
10644 -- inherited in a derivation, or when an inherited operation
10645 -- of a tagged full type overrides the inherited operation of
10646 -- a private extension. Ada 83 had a special rule for the
10647 -- literal case. In Ada 95, the later implicit operation hides
10648 -- the former, and the literal is always the former. In the
10649 -- odd case where both are derived operations declared at the
10650 -- same point, both operations should be declared, and in that
10651 -- case we bypass the following test and proceed to the next
10652 -- part. This can only occur for certain obscure cases in
10653 -- instances, when an operation on a type derived from a formal
10654 -- private type does not override a homograph inherited from
10655 -- the actual. In subsequent derivations of such a type, the
10656 -- DT positions of these operations remain distinct, if they
10659 if Present (Alias (S))
10660 and then (No (Alias (E))
10661 or else Comes_From_Source (E)
10662 or else Is_Abstract_Subprogram (S)
10664 (Is_Dispatching_Operation (E)
10665 and then Is_Overriding_Alias (E, S)))
10666 and then Ekind (E) /= E_Enumeration_Literal
10668 -- When an derived operation is overloaded it may be due to
10669 -- the fact that the full view of a private extension
10670 -- re-inherits. It has to be dealt with.
10672 if Is_Package_Or_Generic_Package (Current_Scope)
10673 and then In_Private_Part (Current_Scope)
10675 Check_Operation_From_Private_View (S, E);
10678 -- In any case the implicit operation remains hidden by the
10679 -- existing declaration, which is overriding. Indicate that
10680 -- E overrides the operation from which S is inherited.
10682 if Present (Alias (S)) then
10683 Set_Overridden_Operation (E, Alias (S));
10684 Inherit_Subprogram_Contract (E, Alias (S));
10687 Set_Overridden_Operation (E, S);
10688 Inherit_Subprogram_Contract (E, S);
10691 if Comes_From_Source (E) then
10692 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10694 -- The Ghost policy in effect at the point of declaration
10695 -- of a parent subprogram and an overriding subprogram
10696 -- must match (SPARK RM 6.9(17)).
10698 Check_Ghost_Overriding (E, S);
10703 -- Within an instance, the renaming declarations for actual
10704 -- subprograms may become ambiguous, but they do not hide each
10707 elsif Ekind (E) /= E_Entry
10708 and then not Comes_From_Source (E)
10709 and then not Is_Generic_Instance (E)
10710 and then (Present (Alias (E))
10711 or else Is_Intrinsic_Subprogram (E))
10712 and then (not In_Instance
10713 or else No (Parent (E))
10714 or else Nkind (Unit_Declaration_Node (E)) /=
10715 N_Subprogram_Renaming_Declaration)
10717 -- A subprogram child unit is not allowed to override an
10718 -- inherited subprogram (10.1.1(20)).
10720 if Is_Child_Unit (S) then
10722 ("child unit overrides inherited subprogram in parent",
10727 if Is_Non_Overriding_Operation (E, S) then
10728 Enter_Overloaded_Entity (S);
10730 if No (Derived_Type)
10731 or else Is_Tagged_Type (Derived_Type)
10733 Check_Dispatching_Operation (S, Empty);
10739 -- E is a derived operation or an internal operator which
10740 -- is being overridden. Remove E from further visibility.
10741 -- Furthermore, if E is a dispatching operation, it must be
10742 -- replaced in the list of primitive operations of its type
10743 -- (see Override_Dispatching_Operation).
10745 Overridden_Subp := E;
10751 Prev := First_Entity (Current_Scope);
10752 while Present (Prev) and then Next_Entity (Prev) /= E loop
10753 Next_Entity (Prev);
10756 -- It is possible for E to be in the current scope and
10757 -- yet not in the entity chain. This can only occur in a
10758 -- generic context where E is an implicit concatenation
10759 -- in the formal part, because in a generic body the
10760 -- entity chain starts with the formals.
10762 -- In GNATprove mode, a wrapper for an operation with
10763 -- axiomatization may be a homonym of another declaration
10764 -- for an actual subprogram (needs refinement ???).
10768 and then GNATprove_Mode
10770 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10771 N_Subprogram_Renaming_Declaration
10775 pragma Assert (Chars (E) = Name_Op_Concat);
10780 -- E must be removed both from the entity_list of the
10781 -- current scope, and from the visibility chain.
10783 if Debug_Flag_E then
10784 Write_Str ("Override implicit operation ");
10785 Write_Int (Int (E));
10789 -- If E is a predefined concatenation, it stands for four
10790 -- different operations. As a result, a single explicit
10791 -- declaration does not hide it. In a possible ambiguous
10792 -- situation, Disambiguate chooses the user-defined op,
10793 -- so it is correct to retain the previous internal one.
10795 if Chars (E) /= Name_Op_Concat
10796 or else Ekind (E) /= E_Operator
10798 -- For nondispatching derived operations that are
10799 -- overridden by a subprogram declared in the private
10800 -- part of a package, we retain the derived subprogram
10801 -- but mark it as not immediately visible. If the
10802 -- derived operation was declared in the visible part
10803 -- then this ensures that it will still be visible
10804 -- outside the package with the proper signature
10805 -- (calls from outside must also be directed to this
10806 -- version rather than the overriding one, unlike the
10807 -- dispatching case). Calls from inside the package
10808 -- will still resolve to the overriding subprogram
10809 -- since the derived one is marked as not visible
10810 -- within the package.
10812 -- If the private operation is dispatching, we achieve
10813 -- the overriding by keeping the implicit operation
10814 -- but setting its alias to be the overriding one. In
10815 -- this fashion the proper body is executed in all
10816 -- cases, but the original signature is used outside
10819 -- If the overriding is not in the private part, we
10820 -- remove the implicit operation altogether.
10822 if Is_Private_Declaration (S) then
10823 if not Is_Dispatching_Operation (E) then
10824 Set_Is_Immediately_Visible (E, False);
10826 -- Work done in Override_Dispatching_Operation,
10827 -- so nothing else needs to be done here.
10833 -- Find predecessor of E in Homonym chain
10835 if E = Current_Entity (E) then
10838 Prev_Vis := Current_Entity (E);
10839 while Homonym (Prev_Vis) /= E loop
10840 Prev_Vis := Homonym (Prev_Vis);
10844 if Prev_Vis /= Empty then
10846 -- Skip E in the visibility chain
10848 Set_Homonym (Prev_Vis, Homonym (E));
10851 Set_Name_Entity_Id (Chars (E), Homonym (E));
10854 Set_Next_Entity (Prev, Next_Entity (E));
10856 if No (Next_Entity (Prev)) then
10857 Set_Last_Entity (Current_Scope, Prev);
10862 Enter_Overloaded_Entity (S);
10864 -- For entities generated by Derive_Subprograms the
10865 -- overridden operation is the inherited primitive
10866 -- (which is available through the attribute alias).
10868 if not (Comes_From_Source (E))
10869 and then Is_Dispatching_Operation (E)
10870 and then Find_Dispatching_Type (E) =
10871 Find_Dispatching_Type (S)
10872 and then Present (Alias (E))
10873 and then Comes_From_Source (Alias (E))
10875 Set_Overridden_Operation (S, Alias (E));
10876 Inherit_Subprogram_Contract (S, Alias (E));
10878 -- Normal case of setting entity as overridden
10880 -- Note: Static_Initialization and Overridden_Operation
10881 -- attributes use the same field in subprogram entities.
10882 -- Static_Initialization is only defined for internal
10883 -- initialization procedures, where Overridden_Operation
10884 -- is irrelevant. Therefore the setting of this attribute
10885 -- must check whether the target is an init_proc.
10887 elsif not Is_Init_Proc (S) then
10888 Set_Overridden_Operation (S, E);
10889 Inherit_Subprogram_Contract (S, E);
10892 Check_Overriding_Indicator (S, E, Is_Primitive => True);
10894 -- The Ghost policy in effect at the point of declaration
10895 -- of a parent subprogram and an overriding subprogram
10896 -- must match (SPARK RM 6.9(17)).
10898 Check_Ghost_Overriding (S, E);
10900 -- If S is a user-defined subprogram or a null procedure
10901 -- expanded to override an inherited null procedure, or a
10902 -- predefined dispatching primitive then indicate that E
10903 -- overrides the operation from which S is inherited.
10905 if Comes_From_Source (S)
10907 (Present (Parent (S))
10909 Nkind (Parent (S)) = N_Procedure_Specification
10911 Null_Present (Parent (S)))
10913 (Present (Alias (E))
10915 Is_Predefined_Dispatching_Operation (Alias (E)))
10917 if Present (Alias (E)) then
10918 Set_Overridden_Operation (S, Alias (E));
10919 Inherit_Subprogram_Contract (S, Alias (E));
10923 if Is_Dispatching_Operation (E) then
10925 -- An overriding dispatching subprogram inherits the
10926 -- convention of the overridden subprogram (AI-117).
10928 Set_Convention (S, Convention (E));
10929 Check_Dispatching_Operation (S, E);
10932 Check_Dispatching_Operation (S, Empty);
10935 Check_For_Primitive_Subprogram
10936 (Is_Primitive_Subp, Is_Overriding => True);
10937 goto Check_Inequality;
10940 -- Apparent redeclarations in instances can occur when two
10941 -- formal types get the same actual type. The subprograms in
10942 -- in the instance are legal, even if not callable from the
10943 -- outside. Calls from within are disambiguated elsewhere.
10944 -- For dispatching operations in the visible part, the usual
10945 -- rules apply, and operations with the same profile are not
10946 -- legal (B830001).
10948 elsif (In_Instance_Visible_Part
10949 and then not Is_Dispatching_Operation (E))
10950 or else In_Instance_Not_Visible
10954 -- Here we have a real error (identical profile)
10957 Error_Msg_Sloc := Sloc (E);
10959 -- Avoid cascaded errors if the entity appears in
10960 -- subsequent calls.
10962 Set_Scope (S, Current_Scope);
10964 -- Generate error, with extra useful warning for the case
10965 -- of a generic instance with no completion.
10967 if Is_Generic_Instance (S)
10968 and then not Has_Completion (E)
10971 ("instantiation cannot provide body for&", S);
10972 Error_Msg_N ("\& conflicts with declaration#", S);
10974 Error_Msg_N ("& conflicts with declaration#", S);
10981 -- If one subprogram has an access parameter and the other
10982 -- a parameter of an access type, calls to either might be
10983 -- ambiguous. Verify that parameters match except for the
10984 -- access parameter.
10986 if May_Hide_Profile then
10992 F1 := First_Formal (S);
10993 F2 := First_Formal (E);
10994 while Present (F1) and then Present (F2) loop
10995 if Is_Access_Type (Etype (F1)) then
10996 if not Is_Access_Type (Etype (F2))
10997 or else not Conforming_Types
10998 (Designated_Type (Etype (F1)),
10999 Designated_Type (Etype (F2)),
11002 May_Hide_Profile := False;
11006 not Conforming_Types
11007 (Etype (F1), Etype (F2), Type_Conformant)
11009 May_Hide_Profile := False;
11016 if May_Hide_Profile
11020 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11029 -- On exit, we know that S is a new entity
11031 Enter_Overloaded_Entity (S);
11032 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11033 Check_Overriding_Indicator
11034 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11036 -- The Ghost policy in effect at the point of declaration of a parent
11037 -- subprogram and an overriding subprogram must match
11038 -- (SPARK RM 6.9(17)).
11040 Check_Ghost_Overriding (S, Overridden_Subp);
11042 -- Overloading is not allowed in SPARK, except for operators
11044 if Nkind (S) /= N_Defining_Operator_Symbol then
11045 Error_Msg_Sloc := Sloc (Homonym (S));
11046 Check_SPARK_05_Restriction
11047 ("overloading not allowed with entity#", S);
11050 -- If S is a derived operation for an untagged type then by
11051 -- definition it's not a dispatching operation (even if the parent
11052 -- operation was dispatching), so Check_Dispatching_Operation is not
11053 -- called in that case.
11055 if No (Derived_Type)
11056 or else Is_Tagged_Type (Derived_Type)
11058 Check_Dispatching_Operation (S, Empty);
11062 -- If this is a user-defined equality operator that is not a derived
11063 -- subprogram, create the corresponding inequality. If the operation is
11064 -- dispatching, the expansion is done elsewhere, and we do not create
11065 -- an explicit inequality operation.
11067 <<Check_Inequality>>
11068 if Chars (S) = Name_Op_Eq
11069 and then Etype (S) = Standard_Boolean
11070 and then Present (Parent (S))
11071 and then not Is_Dispatching_Operation (S)
11073 Make_Inequality_Operator (S);
11074 Check_Untagged_Equality (S);
11076 end New_Overloaded_Entity;
11078 ---------------------
11079 -- Process_Formals --
11080 ---------------------
11082 procedure Process_Formals
11084 Related_Nod : Node_Id)
11086 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11087 -- Determine whether an access type designates a type coming from a
11090 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11091 -- Check whether the default has a class-wide type. After analysis the
11092 -- default has the type of the formal, so we must also check explicitly
11093 -- for an access attribute.
11095 ----------------------------------
11096 -- Designates_From_Limited_With --
11097 ----------------------------------
11099 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11100 Desig : Entity_Id := Typ;
11103 if Is_Access_Type (Desig) then
11104 Desig := Directly_Designated_Type (Desig);
11107 if Is_Class_Wide_Type (Desig) then
11108 Desig := Root_Type (Desig);
11112 Ekind (Desig) = E_Incomplete_Type
11113 and then From_Limited_With (Desig);
11114 end Designates_From_Limited_With;
11116 ---------------------------
11117 -- Is_Class_Wide_Default --
11118 ---------------------------
11120 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11122 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11123 or else (Nkind (D) = N_Attribute_Reference
11124 and then Attribute_Name (D) = Name_Access
11125 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11126 end Is_Class_Wide_Default;
11130 Context : constant Node_Id := Parent (Parent (T));
11132 Formal : Entity_Id;
11133 Formal_Type : Entity_Id;
11134 Param_Spec : Node_Id;
11137 Num_Out_Params : Nat := 0;
11138 First_Out_Param : Entity_Id := Empty;
11139 -- Used for setting Is_Only_Out_Parameter
11141 -- Start of processing for Process_Formals
11144 -- In order to prevent premature use of the formals in the same formal
11145 -- part, the Ekind is left undefined until all default expressions are
11146 -- analyzed. The Ekind is established in a separate loop at the end.
11148 Param_Spec := First (T);
11149 while Present (Param_Spec) loop
11150 Formal := Defining_Identifier (Param_Spec);
11151 Set_Never_Set_In_Source (Formal, True);
11152 Enter_Name (Formal);
11154 -- Case of ordinary parameters
11156 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11157 Find_Type (Parameter_Type (Param_Spec));
11158 Ptype := Parameter_Type (Param_Spec);
11160 if Ptype = Error then
11164 Formal_Type := Entity (Ptype);
11166 if Is_Incomplete_Type (Formal_Type)
11168 (Is_Class_Wide_Type (Formal_Type)
11169 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11171 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11172 -- primitive operations, as long as their completion is
11173 -- in the same declarative part. If in the private part
11174 -- this means that the type cannot be a Taft-amendment type.
11175 -- Check is done on package exit. For access to subprograms,
11176 -- the use is legal for Taft-amendment types.
11178 -- Ada 2012: tagged incomplete types are allowed as generic
11179 -- formal types. They do not introduce dependencies and the
11180 -- corresponding generic subprogram does not have a delayed
11181 -- freeze, because it does not need a freeze node. However,
11182 -- it is still the case that untagged incomplete types cannot
11183 -- be Taft-amendment types and must be completed in private
11184 -- part, so the subprogram must appear in the list of private
11185 -- dependents of the type.
11187 if Is_Tagged_Type (Formal_Type)
11188 or else (Ada_Version >= Ada_2012
11189 and then not From_Limited_With (Formal_Type)
11190 and then not Is_Generic_Type (Formal_Type))
11192 if Ekind (Scope (Current_Scope)) = E_Package
11193 and then not Is_Generic_Type (Formal_Type)
11194 and then not Is_Class_Wide_Type (Formal_Type)
11197 (Parent (T), N_Access_Function_Definition,
11198 N_Access_Procedure_Definition)
11200 Append_Elmt (Current_Scope,
11201 Private_Dependents (Base_Type (Formal_Type)));
11203 -- Freezing is delayed to ensure that Register_Prim
11204 -- will get called for this operation, which is needed
11205 -- in cases where static dispatch tables aren't built.
11206 -- (Note that the same is done for controlling access
11207 -- parameter cases in function Access_Definition.)
11209 if not Is_Thunk (Current_Scope) then
11210 Set_Has_Delayed_Freeze (Current_Scope);
11215 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11216 N_Access_Procedure_Definition)
11218 -- AI05-0151: Tagged incomplete types are allowed in all
11219 -- formal parts. Untagged incomplete types are not allowed
11220 -- in bodies. Limited views of either kind are not allowed
11221 -- if there is no place at which the non-limited view can
11222 -- become available.
11224 -- Incomplete formal untagged types are not allowed in
11225 -- subprogram bodies (but are legal in their declarations).
11226 -- This excludes bodies created for null procedures, which
11227 -- are basic declarations.
11229 if Is_Generic_Type (Formal_Type)
11230 and then not Is_Tagged_Type (Formal_Type)
11231 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11234 ("invalid use of formal incomplete type", Param_Spec);
11236 elsif Ada_Version >= Ada_2012 then
11237 if Is_Tagged_Type (Formal_Type)
11238 and then (not From_Limited_With (Formal_Type)
11239 or else not In_Package_Body)
11243 elsif Nkind_In (Context, N_Accept_Statement,
11244 N_Accept_Alternative,
11246 or else (Nkind (Context) = N_Subprogram_Body
11247 and then Comes_From_Source (Context))
11250 ("invalid use of untagged incomplete type &",
11251 Ptype, Formal_Type);
11256 ("invalid use of incomplete type&",
11257 Param_Spec, Formal_Type);
11259 -- Further checks on the legality of incomplete types
11260 -- in formal parts are delayed until the freeze point
11261 -- of the enclosing subprogram or access to subprogram.
11265 elsif Ekind (Formal_Type) = E_Void then
11267 ("premature use of&",
11268 Parameter_Type (Param_Spec), Formal_Type);
11271 -- Ada 2012 (AI-142): Handle aliased parameters
11273 if Ada_Version >= Ada_2012
11274 and then Aliased_Present (Param_Spec)
11276 Set_Is_Aliased (Formal);
11279 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11280 -- declaration corresponding to the null-excluding type of the
11281 -- formal in the enclosing scope. Finally, replace the parameter
11282 -- type of the formal with the internal subtype.
11284 if Ada_Version >= Ada_2005
11285 and then Null_Exclusion_Present (Param_Spec)
11287 if not Is_Access_Type (Formal_Type) then
11289 ("`NOT NULL` allowed only for an access type", Param_Spec);
11292 if Can_Never_Be_Null (Formal_Type)
11293 and then Comes_From_Source (Related_Nod)
11296 ("`NOT NULL` not allowed (& already excludes null)",
11297 Param_Spec, Formal_Type);
11301 Create_Null_Excluding_Itype
11303 Related_Nod => Related_Nod,
11304 Scope_Id => Scope (Current_Scope));
11306 -- If the designated type of the itype is an itype that is
11307 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11308 -- on the access subtype, to prevent order-of-elaboration
11309 -- issues in the backend.
11312 -- type T is access procedure;
11313 -- procedure Op (O : not null T);
11315 if Is_Itype (Directly_Designated_Type (Formal_Type))
11317 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11319 Set_Has_Delayed_Freeze (Formal_Type);
11324 -- An access formal type
11328 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11330 -- No need to continue if we already notified errors
11332 if not Present (Formal_Type) then
11336 -- Ada 2005 (AI-254)
11339 AD : constant Node_Id :=
11340 Access_To_Subprogram_Definition
11341 (Parameter_Type (Param_Spec));
11343 if Present (AD) and then Protected_Present (AD) then
11345 Replace_Anonymous_Access_To_Protected_Subprogram
11351 Set_Etype (Formal, Formal_Type);
11353 -- Deal with default expression if present
11355 Default := Expression (Param_Spec);
11357 if Present (Default) then
11358 Check_SPARK_05_Restriction
11359 ("default expression is not allowed", Default);
11361 if Out_Present (Param_Spec) then
11363 ("default initialization only allowed for IN parameters",
11367 -- Do the special preanalysis of the expression (see section on
11368 -- "Handling of Default Expressions" in the spec of package Sem).
11370 Preanalyze_Spec_Expression (Default, Formal_Type);
11372 -- An access to constant cannot be the default for
11373 -- an access parameter that is an access to variable.
11375 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11376 and then not Is_Access_Constant (Formal_Type)
11377 and then Is_Access_Type (Etype (Default))
11378 and then Is_Access_Constant (Etype (Default))
11381 ("formal that is access to variable cannot be initialized "
11382 & "with an access-to-constant expression", Default);
11385 -- Check that the designated type of an access parameter's default
11386 -- is not a class-wide type unless the parameter's designated type
11387 -- is also class-wide.
11389 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11390 and then not Designates_From_Limited_With (Formal_Type)
11391 and then Is_Class_Wide_Default (Default)
11392 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11395 ("access to class-wide expression not allowed here", Default);
11398 -- Check incorrect use of dynamically tagged expressions
11400 if Is_Tagged_Type (Formal_Type) then
11401 Check_Dynamically_Tagged_Expression
11403 Typ => Formal_Type,
11404 Related_Nod => Default);
11408 -- Ada 2005 (AI-231): Static checks
11410 if Ada_Version >= Ada_2005
11411 and then Is_Access_Type (Etype (Formal))
11412 and then Can_Never_Be_Null (Etype (Formal))
11414 Null_Exclusion_Static_Checks (Param_Spec);
11417 -- The following checks are relevant only when SPARK_Mode is on as
11418 -- these are not standard Ada legality rules.
11420 if SPARK_Mode = On then
11421 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11423 -- A function cannot have a parameter of mode IN OUT or OUT
11426 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11428 ("function cannot have parameter of mode `OUT` or "
11429 & "`IN OUT`", Formal);
11432 -- A procedure cannot have an effectively volatile formal
11433 -- parameter of mode IN because it behaves as a constant
11434 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11436 elsif Ekind (Scope (Formal)) = E_Procedure
11437 and then Ekind (Formal) = E_In_Parameter
11438 and then Is_Effectively_Volatile (Formal)
11441 ("formal parameter of mode `IN` cannot be volatile", Formal);
11449 -- If this is the formal part of a function specification, analyze the
11450 -- subtype mark in the context where the formals are visible but not
11451 -- yet usable, and may hide outer homographs.
11453 if Nkind (Related_Nod) = N_Function_Specification then
11454 Analyze_Return_Type (Related_Nod);
11457 -- Now set the kind (mode) of each formal
11459 Param_Spec := First (T);
11460 while Present (Param_Spec) loop
11461 Formal := Defining_Identifier (Param_Spec);
11462 Set_Formal_Mode (Formal);
11464 if Ekind (Formal) = E_In_Parameter then
11465 Set_Default_Value (Formal, Expression (Param_Spec));
11467 if Present (Expression (Param_Spec)) then
11468 Default := Expression (Param_Spec);
11470 if Is_Scalar_Type (Etype (Default)) then
11471 if Nkind (Parameter_Type (Param_Spec)) /=
11472 N_Access_Definition
11474 Formal_Type := Entity (Parameter_Type (Param_Spec));
11478 (Related_Nod, Parameter_Type (Param_Spec));
11481 Apply_Scalar_Range_Check (Default, Formal_Type);
11485 elsif Ekind (Formal) = E_Out_Parameter then
11486 Num_Out_Params := Num_Out_Params + 1;
11488 if Num_Out_Params = 1 then
11489 First_Out_Param := Formal;
11492 elsif Ekind (Formal) = E_In_Out_Parameter then
11493 Num_Out_Params := Num_Out_Params + 1;
11496 -- Skip remaining processing if formal type was in error
11498 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11499 goto Next_Parameter;
11502 -- Force call by reference if aliased
11505 Conv : constant Convention_Id := Convention (Etype (Formal));
11507 if Is_Aliased (Formal) then
11508 Set_Mechanism (Formal, By_Reference);
11510 -- Warn if user asked this to be passed by copy
11512 if Conv = Convention_Ada_Pass_By_Copy then
11514 ("cannot pass aliased parameter & by copy??", Formal);
11517 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11519 elsif Conv = Convention_Ada_Pass_By_Copy then
11520 Set_Mechanism (Formal, By_Copy);
11522 elsif Conv = Convention_Ada_Pass_By_Reference then
11523 Set_Mechanism (Formal, By_Reference);
11531 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11532 Set_Is_Only_Out_Parameter (First_Out_Param);
11534 end Process_Formals;
11536 ----------------------------
11537 -- Reference_Body_Formals --
11538 ----------------------------
11540 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11545 if Error_Posted (Spec) then
11549 -- Iterate over both lists. They may be of different lengths if the two
11550 -- specs are not conformant.
11552 Fs := First_Formal (Spec);
11553 Fb := First_Formal (Bod);
11554 while Present (Fs) and then Present (Fb) loop
11555 Generate_Reference (Fs, Fb, 'b');
11557 if Style_Check then
11558 Style.Check_Identifier (Fb, Fs);
11561 Set_Spec_Entity (Fb, Fs);
11562 Set_Referenced (Fs, False);
11566 end Reference_Body_Formals;
11568 -------------------------
11569 -- Set_Actual_Subtypes --
11570 -------------------------
11572 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11574 Formal : Entity_Id;
11576 First_Stmt : Node_Id := Empty;
11577 AS_Needed : Boolean;
11580 -- If this is an empty initialization procedure, no need to create
11581 -- actual subtypes (small optimization).
11583 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11587 -- The subtype declarations may freeze the formals. The body generated
11588 -- for an expression function is not a freeze point, so do not emit
11589 -- these declarations (small loss of efficiency in rare cases).
11591 if Nkind (N) = N_Subprogram_Body
11592 and then Was_Expression_Function (N)
11597 Formal := First_Formal (Subp);
11598 while Present (Formal) loop
11599 T := Etype (Formal);
11601 -- We never need an actual subtype for a constrained formal
11603 if Is_Constrained (T) then
11604 AS_Needed := False;
11606 -- If we have unknown discriminants, then we do not need an actual
11607 -- subtype, or more accurately we cannot figure it out. Note that
11608 -- all class-wide types have unknown discriminants.
11610 elsif Has_Unknown_Discriminants (T) then
11611 AS_Needed := False;
11613 -- At this stage we have an unconstrained type that may need an
11614 -- actual subtype. For sure the actual subtype is needed if we have
11615 -- an unconstrained array type. However, in an instance, the type
11616 -- may appear as a subtype of the full view, while the actual is
11617 -- in fact private (in which case no actual subtype is needed) so
11618 -- check the kind of the base type.
11620 elsif Is_Array_Type (Base_Type (T)) then
11623 -- The only other case needing an actual subtype is an unconstrained
11624 -- record type which is an IN parameter (we cannot generate actual
11625 -- subtypes for the OUT or IN OUT case, since an assignment can
11626 -- change the discriminant values. However we exclude the case of
11627 -- initialization procedures, since discriminants are handled very
11628 -- specially in this context, see the section entitled "Handling of
11629 -- Discriminants" in Einfo.
11631 -- We also exclude the case of Discrim_SO_Functions (functions used
11632 -- in front-end layout mode for size/offset values), since in such
11633 -- functions only discriminants are referenced, and not only are such
11634 -- subtypes not needed, but they cannot always be generated, because
11635 -- of order of elaboration issues.
11637 elsif Is_Record_Type (T)
11638 and then Ekind (Formal) = E_In_Parameter
11639 and then Chars (Formal) /= Name_uInit
11640 and then not Is_Unchecked_Union (T)
11641 and then not Is_Discrim_SO_Function (Subp)
11645 -- All other cases do not need an actual subtype
11648 AS_Needed := False;
11651 -- Generate actual subtypes for unconstrained arrays and
11652 -- unconstrained discriminated records.
11655 if Nkind (N) = N_Accept_Statement then
11657 -- If expansion is active, the formal is replaced by a local
11658 -- variable that renames the corresponding entry of the
11659 -- parameter block, and it is this local variable that may
11660 -- require an actual subtype.
11662 if Expander_Active then
11663 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11665 Decl := Build_Actual_Subtype (T, Formal);
11668 if Present (Handled_Statement_Sequence (N)) then
11670 First (Statements (Handled_Statement_Sequence (N)));
11671 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11672 Mark_Rewrite_Insertion (Decl);
11674 -- If the accept statement has no body, there will be no
11675 -- reference to the actuals, so no need to compute actual
11682 Decl := Build_Actual_Subtype (T, Formal);
11683 Prepend (Decl, Declarations (N));
11684 Mark_Rewrite_Insertion (Decl);
11687 -- The declaration uses the bounds of an existing object, and
11688 -- therefore needs no constraint checks.
11690 Analyze (Decl, Suppress => All_Checks);
11691 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11693 -- We need to freeze manually the generated type when it is
11694 -- inserted anywhere else than in a declarative part.
11696 if Present (First_Stmt) then
11697 Insert_List_Before_And_Analyze (First_Stmt,
11698 Freeze_Entity (Defining_Identifier (Decl), N));
11700 -- Ditto if the type has a dynamic predicate, because the
11701 -- generated function will mention the actual subtype. The
11702 -- predicate may come from an explicit aspect of be inherited.
11704 elsif Has_Predicates (T) then
11705 Insert_List_Before_And_Analyze (Decl,
11706 Freeze_Entity (Defining_Identifier (Decl), N));
11709 if Nkind (N) = N_Accept_Statement
11710 and then Expander_Active
11712 Set_Actual_Subtype (Renamed_Object (Formal),
11713 Defining_Identifier (Decl));
11715 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11719 Next_Formal (Formal);
11721 end Set_Actual_Subtypes;
11723 ---------------------
11724 -- Set_Formal_Mode --
11725 ---------------------
11727 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11728 Spec : constant Node_Id := Parent (Formal_Id);
11729 Id : constant Entity_Id := Scope (Formal_Id);
11732 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11733 -- since we ensure that corresponding actuals are always valid at the
11734 -- point of the call.
11736 if Out_Present (Spec) then
11737 if Ekind_In (Id, E_Entry, E_Entry_Family)
11738 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11740 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11743 if Ekind_In (Id, E_Function, E_Generic_Function) then
11745 -- [IN] OUT parameters allowed for functions in Ada 2012
11747 if Ada_Version >= Ada_2012 then
11749 -- Even in Ada 2012 operators can only have IN parameters
11751 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11752 Error_Msg_N ("operators can only have IN parameters", Spec);
11755 if In_Present (Spec) then
11756 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11758 Set_Ekind (Formal_Id, E_Out_Parameter);
11761 -- But not in earlier versions of Ada
11764 Error_Msg_N ("functions can only have IN parameters", Spec);
11765 Set_Ekind (Formal_Id, E_In_Parameter);
11768 elsif In_Present (Spec) then
11769 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11772 Set_Ekind (Formal_Id, E_Out_Parameter);
11773 Set_Never_Set_In_Source (Formal_Id, True);
11774 Set_Is_True_Constant (Formal_Id, False);
11775 Set_Current_Value (Formal_Id, Empty);
11779 Set_Ekind (Formal_Id, E_In_Parameter);
11782 -- Set Is_Known_Non_Null for access parameters since the language
11783 -- guarantees that access parameters are always non-null. We also set
11784 -- Can_Never_Be_Null, since there is no way to change the value.
11786 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11788 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11789 -- null; In Ada 2005, only if then null_exclusion is explicit.
11791 if Ada_Version < Ada_2005
11792 or else Can_Never_Be_Null (Etype (Formal_Id))
11794 Set_Is_Known_Non_Null (Formal_Id);
11795 Set_Can_Never_Be_Null (Formal_Id);
11798 -- Ada 2005 (AI-231): Null-exclusion access subtype
11800 elsif Is_Access_Type (Etype (Formal_Id))
11801 and then Can_Never_Be_Null (Etype (Formal_Id))
11803 Set_Is_Known_Non_Null (Formal_Id);
11805 -- We can also set Can_Never_Be_Null (thus preventing some junk
11806 -- access checks) for the case of an IN parameter, which cannot
11807 -- be changed, or for an IN OUT parameter, which can be changed but
11808 -- not to a null value. But for an OUT parameter, the initial value
11809 -- passed in can be null, so we can't set this flag in that case.
11811 if Ekind (Formal_Id) /= E_Out_Parameter then
11812 Set_Can_Never_Be_Null (Formal_Id);
11816 Set_Mechanism (Formal_Id, Default_Mechanism);
11817 Set_Formal_Validity (Formal_Id);
11818 end Set_Formal_Mode;
11820 -------------------------
11821 -- Set_Formal_Validity --
11822 -------------------------
11824 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11826 -- If no validity checking, then we cannot assume anything about the
11827 -- validity of parameters, since we do not know there is any checking
11828 -- of the validity on the call side.
11830 if not Validity_Checks_On then
11833 -- If validity checking for parameters is enabled, this means we are
11834 -- not supposed to make any assumptions about argument values.
11836 elsif Validity_Check_Parameters then
11839 -- If we are checking in parameters, we will assume that the caller is
11840 -- also checking parameters, so we can assume the parameter is valid.
11842 elsif Ekind (Formal_Id) = E_In_Parameter
11843 and then Validity_Check_In_Params
11845 Set_Is_Known_Valid (Formal_Id, True);
11847 -- Similar treatment for IN OUT parameters
11849 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11850 and then Validity_Check_In_Out_Params
11852 Set_Is_Known_Valid (Formal_Id, True);
11854 end Set_Formal_Validity;
11856 ------------------------
11857 -- Subtype_Conformant --
11858 ------------------------
11860 function Subtype_Conformant
11861 (New_Id : Entity_Id;
11862 Old_Id : Entity_Id;
11863 Skip_Controlling_Formals : Boolean := False) return Boolean
11867 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
11868 Skip_Controlling_Formals => Skip_Controlling_Formals);
11870 end Subtype_Conformant;
11872 ---------------------
11873 -- Type_Conformant --
11874 ---------------------
11876 function Type_Conformant
11877 (New_Id : Entity_Id;
11878 Old_Id : Entity_Id;
11879 Skip_Controlling_Formals : Boolean := False) return Boolean
11883 May_Hide_Profile := False;
11885 (New_Id, Old_Id, Type_Conformant, False, Result,
11886 Skip_Controlling_Formals => Skip_Controlling_Formals);
11888 end Type_Conformant;
11890 -------------------------------
11891 -- Valid_Operator_Definition --
11892 -------------------------------
11894 procedure Valid_Operator_Definition (Designator : Entity_Id) is
11897 Id : constant Name_Id := Chars (Designator);
11901 F := First_Formal (Designator);
11902 while Present (F) loop
11905 if Present (Default_Value (F)) then
11907 ("default values not allowed for operator parameters",
11910 -- For function instantiations that are operators, we must check
11911 -- separately that the corresponding generic only has in-parameters.
11912 -- For subprogram declarations this is done in Set_Formal_Mode. Such
11913 -- an error could not arise in earlier versions of the language.
11915 elsif Ekind (F) /= E_In_Parameter then
11916 Error_Msg_N ("operators can only have IN parameters", F);
11922 -- Verify that user-defined operators have proper number of arguments
11923 -- First case of operators which can only be unary
11925 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
11928 -- Case of operators which can be unary or binary
11930 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
11931 N_OK := (N in 1 .. 2);
11933 -- All other operators can only be binary
11941 ("incorrect number of arguments for operator", Designator);
11945 and then Base_Type (Etype (Designator)) = Standard_Boolean
11946 and then not Is_Intrinsic_Subprogram (Designator)
11949 ("explicit definition of inequality not allowed", Designator);
11951 end Valid_Operator_Definition;