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);
270 procedure Freeze_Expr_Types (Def_Id : Entity_Id);
271 -- N is an expression function that is a completion and Def_Id its
272 -- defining entity. Freeze before N all the types referenced by the
273 -- expression of the function.
275 -----------------------
276 -- Freeze_Expr_Types --
277 -----------------------
279 procedure Freeze_Expr_Types (Def_Id : Entity_Id) is
280 function Cloned_Expression return Node_Id;
281 -- Build a duplicate of the expression of the return statement that
282 -- has no defining entities shared with the original expression.
284 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result;
285 -- Freeze all types referenced in the subtree rooted at Node
287 -----------------------
288 -- Cloned_Expression --
289 -----------------------
291 function Cloned_Expression return Node_Id is
292 function Clone_Id (Node : Node_Id) return Traverse_Result;
293 -- Tree traversal routine that clones the defining identifier of
294 -- iterator and loop parameter specification nodes.
300 function Clone_Id (Node : Node_Id) return Traverse_Result is
302 if Nkind_In (Node, N_Iterator_Specification,
303 N_Loop_Parameter_Specification)
305 Set_Defining_Identifier (Node,
306 New_Copy (Defining_Identifier (Node)));
312 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id);
316 Dup_Expr : constant Node_Id := New_Copy_Tree (Expr);
318 -- Start of processing for Cloned_Expression
321 -- We must duplicate the expression with semantic information to
322 -- inherit the decoration of global entities in generic instances.
323 -- Set the parent of the new node to be the parent of the original
324 -- to get the proper context, which is needed for complete error
325 -- reporting and for semantic analysis.
327 Set_Parent (Dup_Expr, Parent (Expr));
329 -- Replace the defining identifier of iterators and loop param
330 -- specifications by a clone to ensure that the cloned expression
331 -- and the original expression don't have shared identifiers;
332 -- otherwise, as part of the preanalysis of the expression, these
333 -- shared identifiers may be left decorated with itypes which
334 -- will not be available in the tree passed to the backend.
336 Clone_Def_Ids (Dup_Expr);
339 end Cloned_Expression;
341 ----------------------
342 -- Freeze_Type_Refs --
343 ----------------------
345 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is
346 procedure Check_And_Freeze_Type (Typ : Entity_Id);
347 -- Check that Typ is fully declared and freeze it if so
349 ---------------------------
350 -- Check_And_Freeze_Type --
351 ---------------------------
353 procedure Check_And_Freeze_Type (Typ : Entity_Id) is
355 -- Skip Itypes created by the preanalysis
358 and then Scope_Within_Or_Same (Scope (Typ), Def_Id)
363 -- This provides a better error message than generating
364 -- primitives whose compilation fails much later. Refine
365 -- the error message if possible.
367 Check_Fully_Declared (Typ, Node);
369 if Error_Posted (Node) then
370 if Has_Private_Component (Typ)
371 and then not Is_Private_Type (Typ)
373 Error_Msg_NE ("\type& has private component", Node, Typ);
377 Freeze_Before (N, Typ);
379 end Check_And_Freeze_Type;
381 -- Start of processing for Freeze_Type_Refs
384 -- Check that a type referenced by an entity can be frozen
386 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
387 Check_And_Freeze_Type (Etype (Entity (Node)));
389 -- Check that the enclosing record type can be frozen
391 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
392 Check_And_Freeze_Type (Scope (Entity (Node)));
395 -- Freezing an access type does not freeze the designated type,
396 -- but freezing conversions between access to interfaces requires
397 -- that the interface types themselves be frozen, so that dispatch
398 -- table entities are properly created.
400 -- Unclear whether a more general rule is needed ???
402 elsif Nkind (Node) = N_Type_Conversion
403 and then Is_Access_Type (Etype (Node))
404 and then Is_Interface (Designated_Type (Etype (Node)))
406 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
409 -- No point in posting several errors on the same expression
411 if Serious_Errors_Detected > 0 then
416 end Freeze_Type_Refs;
418 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs);
422 Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id);
423 Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id);
424 Dup_Expr : constant Node_Id := Cloned_Expression;
426 -- Start of processing for Freeze_Expr_Types
429 -- Preanalyze a duplicate of the expression to have available the
430 -- minimum decoration needed to locate referenced unfrozen types
431 -- without adding any decoration to the function expression. This
432 -- preanalysis is performed with errors disabled to avoid reporting
433 -- spurious errors on Ghost entities (since the expression is not
437 Install_Formals (Def_Id);
438 Ignore_Errors_Enable := Ignore_Errors_Enable + 1;
440 Preanalyze_Spec_Expression (Dup_Expr, Etype (Def_Id));
442 Ignore_Errors_Enable := Ignore_Errors_Enable - 1;
445 -- Restore certain attributes of Def_Id since the preanalysis may
446 -- have introduced itypes to this scope, thus modifying attributes
447 -- First_Entity and Last_Entity.
449 Set_First_Entity (Def_Id, Saved_First_Entity);
450 Set_Last_Entity (Def_Id, Saved_Last_Entity);
452 if Present (Last_Entity (Def_Id)) then
453 Set_Next_Entity (Last_Entity (Def_Id), Empty);
456 -- Freeze all types referenced in the expression
458 Freeze_References (Dup_Expr);
459 end Freeze_Expr_Types;
469 Def_Id : Entity_Id := Empty;
471 -- If the expression is a completion, Prev is the entity whose
472 -- declaration is completed. Def_Id is needed to analyze the spec.
474 -- Start of processing for Analyze_Expression_Function
477 -- This is one of the occasions on which we transform the tree during
478 -- semantic analysis. If this is a completion, transform the expression
479 -- function into an equivalent subprogram body, and analyze it.
481 -- Expression functions are inlined unconditionally. The back-end will
482 -- determine whether this is possible.
484 Inline_Processing_Required := True;
486 -- Create a specification for the generated body. This must be done
487 -- prior to the analysis of the initial declaration.
489 New_Spec := Copy_Subprogram_Spec (Spec);
490 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
492 -- If there are previous overloadable entities with the same name,
493 -- check whether any of them is completed by the expression function.
494 -- In a generic context a formal subprogram has no completion.
497 and then Is_Overloadable (Prev)
498 and then not Is_Formal_Subprogram (Prev)
500 Def_Id := Analyze_Subprogram_Specification (Spec);
501 Prev := Find_Corresponding_Spec (N);
503 -- The previous entity may be an expression function as well, in
504 -- which case the redeclaration is illegal.
507 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
508 N_Expression_Function
510 Error_Msg_Sloc := Sloc (Prev);
511 Error_Msg_N ("& conflicts with declaration#", Def_Id);
516 Ret := Make_Simple_Return_Statement (LocX, Expr);
519 Make_Subprogram_Body (Loc,
520 Specification => New_Spec,
521 Declarations => Empty_List,
522 Handled_Statement_Sequence =>
523 Make_Handled_Sequence_Of_Statements (LocX,
524 Statements => New_List (Ret)));
525 Set_Was_Expression_Function (New_Body);
527 -- If the expression completes a generic subprogram, we must create a
528 -- separate node for the body, because at instantiation the original
529 -- node of the generic copy must be a generic subprogram body, and
530 -- cannot be a expression function. Otherwise we just rewrite the
531 -- expression with the non-generic body.
533 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
534 Insert_After (N, New_Body);
536 -- Propagate any aspects or pragmas that apply to the expression
537 -- function to the proper body when the expression function acts
540 if Has_Aspects (N) then
541 Move_Aspects (N, To => New_Body);
544 Relocate_Pragmas_To_Body (New_Body);
546 Rewrite (N, Make_Null_Statement (Loc));
547 Set_Has_Completion (Prev, False);
550 Set_Is_Inlined (Prev);
552 -- If the expression function is a completion, the previous declaration
553 -- must come from source. We know already that it appears in the current
554 -- scope. The entity itself may be internally created if within a body
558 and then Is_Overloadable (Prev)
559 and then not Is_Formal_Subprogram (Prev)
560 and then Comes_From_Source (Parent (Prev))
562 Set_Has_Completion (Prev, False);
563 Set_Is_Inlined (Prev);
565 -- AI12-0103: Expression functions that are a completion freeze their
566 -- expression but don't freeze anything else (unlike regular bodies).
568 -- Note that we cannot defer this freezing to the analysis of the
569 -- expression itself, because a freeze node might appear in a nested
570 -- scope, leading to an elaboration order issue in gigi.
572 Freeze_Expr_Types (Def_Id);
574 -- For navigation purposes, indicate that the function is a body
576 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
577 Rewrite (N, New_Body);
579 -- Remove any existing aspects from the original node because the act
580 -- of rewriting causes the list to be shared between the two nodes.
582 Orig_N := Original_Node (N);
583 Remove_Aspects (Orig_N);
585 -- Propagate any pragmas that apply to expression function to the
586 -- proper body when the expression function acts as a completion.
587 -- Aspects are automatically transfered because of node rewriting.
589 Relocate_Pragmas_To_Body (N);
592 -- Once the aspects of the generated body have been analyzed, create
593 -- a copy for ASIS purposes and associate it with the original node.
595 if Has_Aspects (N) then
596 Set_Aspect_Specifications (Orig_N,
597 New_Copy_List_Tree (Aspect_Specifications (N)));
600 -- Prev is the previous entity with the same name, but it is can
601 -- be an unrelated spec that is not completed by the expression
602 -- function. In that case the relevant entity is the one in the body.
603 -- Not clear that the backend can inline it in this case ???
605 if Has_Completion (Prev) then
607 -- The formals of the expression function are body formals,
608 -- and do not appear in the ali file, which will only contain
609 -- references to the formals of the original subprogram spec.
616 F1 := First_Formal (Def_Id);
617 F2 := First_Formal (Prev);
619 while Present (F1) loop
620 Set_Spec_Entity (F1, F2);
627 Set_Is_Inlined (Defining_Entity (New_Body));
630 -- If this is not a completion, create both a declaration and a body, so
631 -- that the expression can be inlined whenever possible.
634 -- An expression function that is not a completion is not a
635 -- subprogram declaration, and thus cannot appear in a protected
638 if Nkind (Parent (N)) = N_Protected_Definition then
640 ("an expression function is not a legal protected operation", N);
643 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
645 -- Remove any existing aspects from the original node because the act
646 -- of rewriting causes the list to be shared between the two nodes.
648 Orig_N := Original_Node (N);
649 Remove_Aspects (Orig_N);
653 -- Once the aspects of the generated spec have been analyzed, create
654 -- a copy for ASIS purposes and associate it with the original node.
656 if Has_Aspects (N) then
657 Set_Aspect_Specifications (Orig_N,
658 New_Copy_List_Tree (Aspect_Specifications (N)));
661 -- If aspect SPARK_Mode was specified on the body, it needs to be
662 -- repeated both on the generated spec and the body.
664 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
666 if Present (Asp) then
667 Asp := New_Copy_Tree (Asp);
668 Set_Analyzed (Asp, False);
669 Set_Aspect_Specifications (New_Body, New_List (Asp));
672 Def_Id := Defining_Entity (N);
673 Set_Is_Inlined (Def_Id);
675 -- Establish the linkages between the spec and the body. These are
676 -- used when the expression function acts as the prefix of attribute
677 -- 'Access in order to freeze the original expression which has been
678 -- moved to the generated body.
680 Set_Corresponding_Body (N, Defining_Entity (New_Body));
681 Set_Corresponding_Spec (New_Body, Def_Id);
683 -- Within a generic pre-analyze the original expression for name
684 -- capture. The body is also generated but plays no role in
685 -- this because it is not part of the original source.
687 if Inside_A_Generic then
688 Set_Has_Completion (Def_Id);
690 Install_Formals (Def_Id);
691 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
695 -- To prevent premature freeze action, insert the new body at the end
696 -- of the current declarations, or at the end of the package spec.
697 -- However, resolve usage names now, to prevent spurious visibility
698 -- on later entities. Note that the function can now be called in
699 -- the current declarative part, which will appear to be prior to
700 -- the presence of the body in the code. There are nevertheless no
701 -- order of elaboration issues because all name resolution has taken
702 -- place at the point of declaration.
705 Decls : List_Id := List_Containing (N);
706 Expr : constant Node_Id := Expression (Ret);
707 Par : constant Node_Id := Parent (Decls);
708 Typ : constant Entity_Id := Etype (Def_Id);
711 -- If this is a wrapper created for in an instance for a formal
712 -- subprogram, insert body after declaration, to be analyzed when
713 -- the enclosing instance is analyzed.
716 and then Is_Generic_Actual_Subprogram (Def_Id)
718 Insert_After (N, New_Body);
721 if Nkind (Par) = N_Package_Specification
722 and then Decls = Visible_Declarations (Par)
723 and then Present (Private_Declarations (Par))
724 and then not Is_Empty_List (Private_Declarations (Par))
726 Decls := Private_Declarations (Par);
729 Insert_After (Last (Decls), New_Body);
731 -- Preanalyze the expression if not already done above
733 if not Inside_A_Generic then
735 Install_Formals (Def_Id);
736 Preanalyze_Spec_Expression (Expr, Typ);
737 Check_Limited_Return (Original_Node (N), Expr, Typ);
744 -- Check incorrect use of dynamically tagged expression. This doesn't
745 -- fall out automatically when analyzing the generated function body,
746 -- because Check_Dynamically_Tagged_Expression deliberately ignores
747 -- nodes that don't come from source.
750 and then Nkind (Def_Id) in N_Has_Etype
751 and then Is_Tagged_Type (Etype (Def_Id))
753 Check_Dynamically_Tagged_Expression
755 Typ => Etype (Def_Id),
756 Related_Nod => Original_Node (N));
759 -- If the return expression is a static constant, we suppress warning
760 -- messages on unused formals, which in most cases will be noise.
762 Set_Is_Trivial_Subprogram
763 (Defining_Entity (New_Body), Is_OK_Static_Expression (Expr));
764 end Analyze_Expression_Function;
766 ----------------------------------------
767 -- Analyze_Extended_Return_Statement --
768 ----------------------------------------
770 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
772 Check_Compiler_Unit ("extended return statement", N);
773 Analyze_Return_Statement (N);
774 end Analyze_Extended_Return_Statement;
776 ----------------------------
777 -- Analyze_Function_Call --
778 ----------------------------
780 procedure Analyze_Function_Call (N : Node_Id) is
781 Actuals : constant List_Id := Parameter_Associations (N);
782 Func_Nam : constant Node_Id := Name (N);
788 -- A call of the form A.B (X) may be an Ada 2005 call, which is
789 -- rewritten as B (A, X). If the rewriting is successful, the call
790 -- has been analyzed and we just return.
792 if Nkind (Func_Nam) = N_Selected_Component
793 and then Name (N) /= Func_Nam
794 and then Is_Rewrite_Substitution (N)
795 and then Present (Etype (N))
800 -- If error analyzing name, then set Any_Type as result type and return
802 if Etype (Func_Nam) = Any_Type then
803 Set_Etype (N, Any_Type);
807 -- Otherwise analyze the parameters
809 if Present (Actuals) then
810 Actual := First (Actuals);
811 while Present (Actual) loop
813 Check_Parameterless_Call (Actual);
819 end Analyze_Function_Call;
821 -----------------------------
822 -- Analyze_Function_Return --
823 -----------------------------
825 procedure Analyze_Function_Return (N : Node_Id) is
826 Loc : constant Source_Ptr := Sloc (N);
827 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
828 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
830 R_Type : constant Entity_Id := Etype (Scope_Id);
831 -- Function result subtype
833 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
834 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
835 -- aggregate in a return statement.
837 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
838 -- Check that the return_subtype_indication properly matches the result
839 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
841 -----------------------------------
842 -- Check_Aggregate_Accessibility --
843 -----------------------------------
845 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
846 Typ : constant Entity_Id := Etype (Aggr);
853 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
854 Discr := First_Discriminant (Typ);
855 Assoc := First (Component_Associations (Aggr));
856 while Present (Discr) loop
857 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
858 Expr := Expression (Assoc);
860 if Nkind (Expr) = N_Attribute_Reference
861 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
863 Obj := Prefix (Expr);
864 while Nkind_In (Obj, N_Indexed_Component,
865 N_Selected_Component)
870 -- Do not check aliased formals or function calls. A
871 -- run-time check may still be needed ???
873 if Is_Entity_Name (Obj)
874 and then Comes_From_Source (Obj)
876 if Is_Formal (Entity (Obj))
877 and then Is_Aliased (Entity (Obj))
881 elsif Object_Access_Level (Obj) >
882 Scope_Depth (Scope (Scope_Id))
885 ("access discriminant in return aggregate would "
886 & "be a dangling reference", Obj);
892 Next_Discriminant (Discr);
895 end Check_Aggregate_Accessibility;
897 -------------------------------------
898 -- Check_Return_Subtype_Indication --
899 -------------------------------------
901 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
902 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
904 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
905 -- Subtype given in the extended return statement (must match R_Type)
907 Subtype_Ind : constant Node_Id :=
908 Object_Definition (Original_Node (Obj_Decl));
910 procedure Error_No_Match (N : Node_Id);
911 -- Output error messages for case where types do not statically
912 -- match. N is the location for the messages.
918 procedure Error_No_Match (N : Node_Id) is
921 ("subtype must statically match function result subtype", N);
923 if not Predicates_Match (R_Stm_Type, R_Type) then
924 Error_Msg_Node_2 := R_Type;
926 ("\predicate of& does not match predicate of&",
931 -- Start of processing for Check_Return_Subtype_Indication
934 -- First, avoid cascaded errors
936 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
940 -- "return access T" case; check that the return statement also has
941 -- "access T", and that the subtypes statically match:
942 -- if this is an access to subprogram the signatures must match.
944 if Is_Anonymous_Access_Type (R_Type) then
945 if Is_Anonymous_Access_Type (R_Stm_Type) then
946 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
948 if Base_Type (Designated_Type (R_Stm_Type)) /=
949 Base_Type (Designated_Type (R_Type))
950 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
952 Error_No_Match (Subtype_Mark (Subtype_Ind));
956 -- For two anonymous access to subprogram types, the types
957 -- themselves must be type conformant.
959 if not Conforming_Types
960 (R_Stm_Type, R_Type, Fully_Conformant)
962 Error_No_Match (Subtype_Ind);
967 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
970 -- If the return object is of an anonymous access type, then report
971 -- an error if the function's result type is not also anonymous.
973 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
974 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
976 ("anonymous access not allowed for function with named access "
977 & "result", Subtype_Ind);
979 -- Subtype indication case: check that the return object's type is
980 -- covered by the result type, and that the subtypes statically match
981 -- when the result subtype is constrained. Also handle record types
982 -- with unknown discriminants for which we have built the underlying
983 -- record view. Coverage is needed to allow specific-type return
984 -- objects when the result type is class-wide (see AI05-32).
986 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
987 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
991 Underlying_Record_View (Base_Type (R_Stm_Type))))
993 -- A null exclusion may be present on the return type, on the
994 -- function specification, on the object declaration or on the
997 if Is_Access_Type (R_Type)
999 (Can_Never_Be_Null (R_Type)
1000 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1001 Can_Never_Be_Null (R_Stm_Type)
1003 Error_No_Match (Subtype_Ind);
1006 -- AI05-103: for elementary types, subtypes must statically match
1008 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1009 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1010 Error_No_Match (Subtype_Ind);
1014 -- All remaining cases are illegal
1016 -- Note: previous versions of this subprogram allowed the return
1017 -- value to be the ancestor of the return type if the return type
1018 -- was a null extension. This was plainly incorrect.
1022 ("wrong type for return_subtype_indication", Subtype_Ind);
1024 end Check_Return_Subtype_Indication;
1026 ---------------------
1027 -- Local Variables --
1028 ---------------------
1033 -- Start of processing for Analyze_Function_Return
1036 Set_Return_Present (Scope_Id);
1038 if Nkind (N) = N_Simple_Return_Statement then
1039 Expr := Expression (N);
1041 -- Guard against a malformed expression. The parser may have tried to
1042 -- recover but the node is not analyzable.
1044 if Nkind (Expr) = N_Error then
1045 Set_Etype (Expr, Any_Type);
1046 Expander_Mode_Save_And_Set (False);
1050 -- The resolution of a controlled [extension] aggregate associated
1051 -- with a return statement creates a temporary which needs to be
1052 -- finalized on function exit. Wrap the return statement inside a
1053 -- block so that the finalization machinery can detect this case.
1054 -- This early expansion is done only when the return statement is
1055 -- not part of a handled sequence of statements.
1057 if Nkind_In (Expr, N_Aggregate,
1058 N_Extension_Aggregate)
1059 and then Needs_Finalization (R_Type)
1060 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1063 Make_Block_Statement (Loc,
1064 Handled_Statement_Sequence =>
1065 Make_Handled_Sequence_Of_Statements (Loc,
1066 Statements => New_List (Relocate_Node (N)))));
1074 -- Ada 2005 (AI-251): If the type of the returned object is
1075 -- an access to an interface type then we add an implicit type
1076 -- conversion to force the displacement of the "this" pointer to
1077 -- reference the secondary dispatch table. We cannot delay the
1078 -- generation of this implicit conversion until the expansion
1079 -- because in this case the type resolution changes the decoration
1080 -- of the expression node to match R_Type; by contrast, if the
1081 -- returned object is a class-wide interface type then it is too
1082 -- early to generate here the implicit conversion since the return
1083 -- statement may be rewritten by the expander into an extended
1084 -- return statement whose expansion takes care of adding the
1085 -- implicit type conversion to displace the pointer to the object.
1088 and then Serious_Errors_Detected = 0
1089 and then Is_Access_Type (R_Type)
1090 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1091 and then Is_Interface (Designated_Type (R_Type))
1092 and then Is_Progenitor (Designated_Type (R_Type),
1093 Designated_Type (Etype (Expr)))
1095 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1099 Resolve (Expr, R_Type);
1100 Check_Limited_Return (N, Expr, R_Type);
1102 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
1103 Check_Aggregate_Accessibility (Expr);
1107 -- RETURN only allowed in SPARK as the last statement in function
1109 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1111 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1112 or else Present (Next (N)))
1114 Check_SPARK_05_Restriction
1115 ("RETURN should be the last statement in function", N);
1119 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1120 Obj_Decl := Last (Return_Object_Declarations (N));
1122 -- Analyze parts specific to extended_return_statement:
1125 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1126 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1129 Expr := Expression (Obj_Decl);
1131 -- Note: The check for OK_For_Limited_Init will happen in
1132 -- Analyze_Object_Declaration; we treat it as a normal
1133 -- object declaration.
1135 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1138 Check_Return_Subtype_Indication (Obj_Decl);
1140 if Present (HSS) then
1143 if Present (Exception_Handlers (HSS)) then
1145 -- ???Has_Nested_Block_With_Handler needs to be set.
1146 -- Probably by creating an actual N_Block_Statement.
1147 -- Probably in Expand.
1153 -- Mark the return object as referenced, since the return is an
1154 -- implicit reference of the object.
1156 Set_Referenced (Defining_Identifier (Obj_Decl));
1158 Check_References (Stm_Entity);
1160 -- Check RM 6.5 (5.9/3)
1163 if Ada_Version < Ada_2012 then
1165 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1166 -- Can it really happen (extended return???)
1169 ("aliased only allowed for limited return objects "
1170 & "in Ada 2012??", N);
1172 elsif not Is_Limited_View (R_Type) then
1174 ("aliased only allowed for limited return objects", N);
1180 -- Case of Expr present
1184 -- Defend against previous errors
1186 and then Nkind (Expr) /= N_Empty
1187 and then Present (Etype (Expr))
1189 -- Apply constraint check. Note that this is done before the implicit
1190 -- conversion of the expression done for anonymous access types to
1191 -- ensure correct generation of the null-excluding check associated
1192 -- with null-excluding expressions found in return statements.
1194 Apply_Constraint_Check (Expr, R_Type);
1196 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1197 -- type, apply an implicit conversion of the expression to that type
1198 -- to force appropriate static and run-time accessibility checks.
1200 if Ada_Version >= Ada_2005
1201 and then Ekind (R_Type) = E_Anonymous_Access_Type
1203 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1204 Analyze_And_Resolve (Expr, R_Type);
1206 -- If this is a local anonymous access to subprogram, the
1207 -- accessibility check can be applied statically. The return is
1208 -- illegal if the access type of the return expression is declared
1209 -- inside of the subprogram (except if it is the subtype indication
1210 -- of an extended return statement).
1212 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1213 if not Comes_From_Source (Current_Scope)
1214 or else Ekind (Current_Scope) = E_Return_Statement
1219 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1221 Error_Msg_N ("cannot return local access to subprogram", N);
1224 -- The expression cannot be of a formal incomplete type
1226 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1227 and then Is_Generic_Type (Etype (Expr))
1230 ("cannot return expression of a formal incomplete type", N);
1233 -- If the result type is class-wide, then check that the return
1234 -- expression's type is not declared at a deeper level than the
1235 -- function (RM05-6.5(5.6/2)).
1237 if Ada_Version >= Ada_2005
1238 and then Is_Class_Wide_Type (R_Type)
1240 if Type_Access_Level (Etype (Expr)) >
1241 Subprogram_Access_Level (Scope_Id)
1244 ("level of return expression type is deeper than "
1245 & "class-wide function!", Expr);
1249 -- Check incorrect use of dynamically tagged expression
1251 if Is_Tagged_Type (R_Type) then
1252 Check_Dynamically_Tagged_Expression
1258 -- ??? A real run-time accessibility check is needed in cases
1259 -- involving dereferences of access parameters. For now we just
1260 -- check the static cases.
1262 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1263 and then Is_Limited_View (Etype (Scope_Id))
1264 and then Object_Access_Level (Expr) >
1265 Subprogram_Access_Level (Scope_Id)
1267 -- Suppress the message in a generic, where the rewriting
1270 if Inside_A_Generic then
1275 Make_Raise_Program_Error (Loc,
1276 Reason => PE_Accessibility_Check_Failed));
1279 Error_Msg_Warn := SPARK_Mode /= On;
1280 Error_Msg_N ("cannot return a local value by reference<<", N);
1281 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1285 if Known_Null (Expr)
1286 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1287 and then Null_Exclusion_Present (Parent (Scope_Id))
1289 Apply_Compile_Time_Constraint_Error
1291 Msg => "(Ada 2005) null not allowed for "
1292 & "null-excluding return??",
1293 Reason => CE_Null_Not_Allowed);
1296 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1297 -- has no initializing expression.
1299 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1300 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1301 Subprogram_Access_Level (Scope_Id)
1304 ("level of return expression type is deeper than "
1305 & "class-wide function!", Obj_Decl);
1308 end Analyze_Function_Return;
1310 -------------------------------------
1311 -- Analyze_Generic_Subprogram_Body --
1312 -------------------------------------
1314 procedure Analyze_Generic_Subprogram_Body
1318 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1319 Kind : constant Entity_Kind := Ekind (Gen_Id);
1320 Body_Id : Entity_Id;
1325 -- Copy body and disable expansion while analyzing the generic For a
1326 -- stub, do not copy the stub (which would load the proper body), this
1327 -- will be done when the proper body is analyzed.
1329 if Nkind (N) /= N_Subprogram_Body_Stub then
1330 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1333 -- Once the contents of the generic copy and the template are
1334 -- swapped, do the same for their respective aspect specifications.
1336 Exchange_Aspects (N, New_N);
1338 -- Collect all contract-related source pragmas found within the
1339 -- template and attach them to the contract of the subprogram body.
1340 -- This contract is used in the capture of global references within
1343 Create_Generic_Contract (N);
1348 Spec := Specification (N);
1350 -- Within the body of the generic, the subprogram is callable, and
1351 -- behaves like the corresponding non-generic unit.
1353 Body_Id := Defining_Entity (Spec);
1355 if Kind = E_Generic_Procedure
1356 and then Nkind (Spec) /= N_Procedure_Specification
1358 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1361 elsif Kind = E_Generic_Function
1362 and then Nkind (Spec) /= N_Function_Specification
1364 Error_Msg_N ("invalid body for generic function ", Body_Id);
1368 Set_Corresponding_Body (Gen_Decl, Body_Id);
1370 if Has_Completion (Gen_Id)
1371 and then Nkind (Parent (N)) /= N_Subunit
1373 Error_Msg_N ("duplicate generic body", N);
1376 Set_Has_Completion (Gen_Id);
1379 if Nkind (N) = N_Subprogram_Body_Stub then
1380 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1382 Set_Corresponding_Spec (N, Gen_Id);
1385 if Nkind (Parent (N)) = N_Compilation_Unit then
1386 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1389 -- Make generic parameters immediately visible in the body. They are
1390 -- needed to process the formals declarations. Then make the formals
1391 -- visible in a separate step.
1393 Push_Scope (Gen_Id);
1397 First_Ent : Entity_Id;
1400 First_Ent := First_Entity (Gen_Id);
1403 while Present (E) and then not Is_Formal (E) loop
1408 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1410 -- Now generic formals are visible, and the specification can be
1411 -- analyzed, for subsequent conformance check.
1413 Body_Id := Analyze_Subprogram_Specification (Spec);
1415 -- Make formal parameters visible
1419 -- E is the first formal parameter, we loop through the formals
1420 -- installing them so that they will be visible.
1422 Set_First_Entity (Gen_Id, E);
1423 while Present (E) loop
1429 -- Visible generic entity is callable within its own body
1431 Set_Ekind (Gen_Id, Ekind (Body_Id));
1432 Set_Ekind (Body_Id, E_Subprogram_Body);
1433 Set_Convention (Body_Id, Convention (Gen_Id));
1434 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1435 Set_Scope (Body_Id, Scope (Gen_Id));
1437 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1439 if Nkind (N) = N_Subprogram_Body_Stub then
1441 -- No body to analyze, so restore state of generic unit
1443 Set_Ekind (Gen_Id, Kind);
1444 Set_Ekind (Body_Id, Kind);
1446 if Present (First_Ent) then
1447 Set_First_Entity (Gen_Id, First_Ent);
1454 -- If this is a compilation unit, it must be made visible explicitly,
1455 -- because the compilation of the declaration, unlike other library
1456 -- unit declarations, does not. If it is not a unit, the following
1457 -- is redundant but harmless.
1459 Set_Is_Immediately_Visible (Gen_Id);
1460 Reference_Body_Formals (Gen_Id, Body_Id);
1462 if Is_Child_Unit (Gen_Id) then
1463 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1466 Set_Actual_Subtypes (N, Current_Scope);
1468 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1469 Set_SPARK_Pragma_Inherited (Body_Id);
1471 -- Analyze any aspect specifications that appear on the generic
1474 if Has_Aspects (N) then
1475 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
1478 Analyze_Declarations (Declarations (N));
1481 -- Process the contract of the subprogram body after all declarations
1482 -- have been analyzed. This ensures that any contract-related pragmas
1483 -- are available through the N_Contract node of the body.
1485 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1487 Analyze (Handled_Statement_Sequence (N));
1488 Save_Global_References (Original_Node (N));
1490 -- Prior to exiting the scope, include generic formals again (if any
1491 -- are present) in the set of local entities.
1493 if Present (First_Ent) then
1494 Set_First_Entity (Gen_Id, First_Ent);
1497 Check_References (Gen_Id);
1500 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1502 Check_Subprogram_Order (N);
1504 -- Outside of its body, unit is generic again
1506 Set_Ekind (Gen_Id, Kind);
1507 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1510 Style.Check_Identifier (Body_Id, Gen_Id);
1514 end Analyze_Generic_Subprogram_Body;
1516 ----------------------------
1517 -- Analyze_Null_Procedure --
1518 ----------------------------
1520 procedure Analyze_Null_Procedure
1522 Is_Completion : out Boolean)
1524 Loc : constant Source_Ptr := Sloc (N);
1525 Spec : constant Node_Id := Specification (N);
1526 Designator : Entity_Id;
1528 Null_Body : Node_Id := Empty;
1529 Null_Stmt : Node_Id := Null_Statement (Spec);
1533 -- Capture the profile of the null procedure before analysis, for
1534 -- expansion at the freeze point and at each point of call. The body is
1535 -- used if the procedure has preconditions, or if it is a completion. In
1536 -- the first case the body is analyzed at the freeze point, in the other
1537 -- it replaces the null procedure declaration.
1539 -- For a null procedure that comes from source, a NULL statement is
1540 -- provided by the parser, which carries the source location of the
1541 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1542 -- from expansion, create one now.
1544 if No (Null_Stmt) then
1545 Null_Stmt := Make_Null_Statement (Loc);
1549 Make_Subprogram_Body (Loc,
1550 Specification => New_Copy_Tree (Spec),
1551 Declarations => New_List,
1552 Handled_Statement_Sequence =>
1553 Make_Handled_Sequence_Of_Statements (Loc,
1554 Statements => New_List (Null_Stmt)));
1556 -- Create new entities for body and formals
1558 Set_Defining_Unit_Name (Specification (Null_Body),
1559 Make_Defining_Identifier
1560 (Sloc (Defining_Entity (N)),
1561 Chars (Defining_Entity (N))));
1563 Form := First (Parameter_Specifications (Specification (Null_Body)));
1564 while Present (Form) loop
1565 Set_Defining_Identifier (Form,
1566 Make_Defining_Identifier
1567 (Sloc (Defining_Identifier (Form)),
1568 Chars (Defining_Identifier (Form))));
1572 -- Determine whether the null procedure may be a completion of a generic
1573 -- suprogram, in which case we use the new null body as the completion
1574 -- and set minimal semantic information on the original declaration,
1575 -- which is rewritten as a null statement.
1577 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1579 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1580 Insert_Before (N, Null_Body);
1581 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1583 Rewrite (N, Make_Null_Statement (Loc));
1584 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1585 Is_Completion := True;
1589 -- Resolve the types of the formals now, because the freeze point may
1590 -- appear in a different context, e.g. an instantiation.
1592 Form := First (Parameter_Specifications (Specification (Null_Body)));
1593 while Present (Form) loop
1594 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1595 Find_Type (Parameter_Type (Form));
1597 elsif No (Access_To_Subprogram_Definition
1598 (Parameter_Type (Form)))
1600 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1602 -- The case of a null procedure with a formal that is an
1603 -- access-to-subprogram type, and that is used as an actual
1604 -- in an instantiation is left to the enthusiastic reader.
1614 -- If there are previous overloadable entities with the same name, check
1615 -- whether any of them is completed by the null procedure.
1617 if Present (Prev) and then Is_Overloadable (Prev) then
1618 Designator := Analyze_Subprogram_Specification (Spec);
1619 Prev := Find_Corresponding_Spec (N);
1622 if No (Prev) or else not Comes_From_Source (Prev) then
1623 Designator := Analyze_Subprogram_Specification (Spec);
1624 Set_Has_Completion (Designator);
1626 -- Signal to caller that this is a procedure declaration
1628 Is_Completion := False;
1630 -- Null procedures are always inlined, but generic formal subprograms
1631 -- which appear as such in the internal instance of formal packages,
1632 -- need no completion and are not marked Inline.
1635 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1637 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1638 Set_Body_To_Inline (N, Null_Body);
1639 Set_Is_Inlined (Designator);
1643 -- The null procedure is a completion. We unconditionally rewrite
1644 -- this as a null body (even if expansion is not active), because
1645 -- there are various error checks that are applied on this body
1646 -- when it is analyzed (e.g. correct aspect placement).
1648 if Has_Completion (Prev) then
1649 Error_Msg_Sloc := Sloc (Prev);
1650 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1653 Check_Previous_Null_Procedure (N, Prev);
1655 Is_Completion := True;
1656 Rewrite (N, Null_Body);
1659 end Analyze_Null_Procedure;
1661 -----------------------------
1662 -- Analyze_Operator_Symbol --
1663 -----------------------------
1665 -- An operator symbol such as "+" or "and" may appear in context where the
1666 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1667 -- is just a string, as in (conjunction = "or"). In these cases the parser
1668 -- generates this node, and the semantics does the disambiguation. Other
1669 -- such case are actuals in an instantiation, the generic unit in an
1670 -- instantiation, and pragma arguments.
1672 procedure Analyze_Operator_Symbol (N : Node_Id) is
1673 Par : constant Node_Id := Parent (N);
1676 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1677 or else Nkind (Par) = N_Function_Instantiation
1678 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1679 or else (Nkind (Par) = N_Pragma_Argument_Association
1680 and then not Is_Pragma_String_Literal (Par))
1681 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1682 or else (Nkind (Par) = N_Attribute_Reference
1683 and then Attribute_Name (Par) /= Name_Value)
1685 Find_Direct_Name (N);
1688 Change_Operator_Symbol_To_String_Literal (N);
1691 end Analyze_Operator_Symbol;
1693 -----------------------------------
1694 -- Analyze_Parameter_Association --
1695 -----------------------------------
1697 procedure Analyze_Parameter_Association (N : Node_Id) is
1699 Analyze (Explicit_Actual_Parameter (N));
1700 end Analyze_Parameter_Association;
1702 ----------------------------
1703 -- Analyze_Procedure_Call --
1704 ----------------------------
1706 -- WARNING: This routine manages Ghost regions. Return statements must be
1707 -- replaced by gotos which jump to the end of the routine and restore the
1710 procedure Analyze_Procedure_Call (N : Node_Id) is
1711 procedure Analyze_Call_And_Resolve;
1712 -- Do Analyze and Resolve calls for procedure call. At the end, check
1713 -- for illegal order dependence.
1714 -- ??? where is the check for illegal order dependencies?
1716 ------------------------------
1717 -- Analyze_Call_And_Resolve --
1718 ------------------------------
1720 procedure Analyze_Call_And_Resolve is
1722 if Nkind (N) = N_Procedure_Call_Statement then
1724 Resolve (N, Standard_Void_Type);
1728 end Analyze_Call_And_Resolve;
1732 Actuals : constant List_Id := Parameter_Associations (N);
1733 Loc : constant Source_Ptr := Sloc (N);
1734 P : constant Node_Id := Name (N);
1736 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1737 -- Save the Ghost mode to restore on exit
1742 -- Start of processing for Analyze_Procedure_Call
1745 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1746 -- a procedure call or an entry call. The prefix may denote an access
1747 -- to subprogram type, in which case an implicit dereference applies.
1748 -- If the prefix is an indexed component (without implicit dereference)
1749 -- then the construct denotes a call to a member of an entire family.
1750 -- If the prefix is a simple name, it may still denote a call to a
1751 -- parameterless member of an entry family. Resolution of these various
1752 -- interpretations is delicate.
1754 -- Do not analyze machine code statements to avoid rejecting them in
1757 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1758 Set_Etype (P, Standard_Void_Type);
1763 -- If this is a call of the form Obj.Op, the call may have been analyzed
1764 -- and possibly rewritten into a block, in which case we are done.
1766 if Analyzed (N) then
1770 -- If there is an error analyzing the name (which may have been
1771 -- rewritten if the original call was in prefix notation) then error
1772 -- has been emitted already, mark node and return.
1774 if Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1775 Set_Etype (N, Any_Type);
1779 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1780 -- Set the mode now to ensure that any nodes generated during analysis
1781 -- and expansion are properly marked as Ghost.
1783 Mark_And_Set_Ghost_Procedure_Call (N);
1785 -- Otherwise analyze the parameters
1787 if Present (Actuals) then
1788 Actual := First (Actuals);
1790 while Present (Actual) loop
1792 Check_Parameterless_Call (Actual);
1797 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1799 if Nkind (P) = N_Attribute_Reference
1800 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1802 Name_Elab_Subp_Body)
1804 if Present (Actuals) then
1806 ("no parameters allowed for this call", First (Actuals));
1810 Set_Etype (N, Standard_Void_Type);
1813 elsif Is_Entity_Name (P)
1814 and then Is_Record_Type (Etype (Entity (P)))
1815 and then Remote_AST_I_Dereference (P)
1819 elsif Is_Entity_Name (P)
1820 and then Ekind (Entity (P)) /= E_Entry_Family
1822 if Is_Access_Type (Etype (P))
1823 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1824 and then No (Actuals)
1825 and then Comes_From_Source (N)
1827 Error_Msg_N ("missing explicit dereference in call", N);
1830 Analyze_Call_And_Resolve;
1832 -- If the prefix is the simple name of an entry family, this is a
1833 -- parameterless call from within the task body itself.
1835 elsif Is_Entity_Name (P)
1836 and then Nkind (P) = N_Identifier
1837 and then Ekind (Entity (P)) = E_Entry_Family
1838 and then Present (Actuals)
1839 and then No (Next (First (Actuals)))
1841 -- Can be call to parameterless entry family. What appears to be the
1842 -- sole argument is in fact the entry index. Rewrite prefix of node
1843 -- accordingly. Source representation is unchanged by this
1847 Make_Indexed_Component (Loc,
1849 Make_Selected_Component (Loc,
1850 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1851 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1852 Expressions => Actuals);
1853 Set_Name (N, New_N);
1854 Set_Etype (New_N, Standard_Void_Type);
1855 Set_Parameter_Associations (N, No_List);
1856 Analyze_Call_And_Resolve;
1858 elsif Nkind (P) = N_Explicit_Dereference then
1859 if Ekind (Etype (P)) = E_Subprogram_Type then
1860 Analyze_Call_And_Resolve;
1862 Error_Msg_N ("expect access to procedure in call", P);
1865 -- The name can be a selected component or an indexed component that
1866 -- yields an access to subprogram. Such a prefix is legal if the call
1867 -- has parameter associations.
1869 elsif Is_Access_Type (Etype (P))
1870 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1872 if Present (Actuals) then
1873 Analyze_Call_And_Resolve;
1875 Error_Msg_N ("missing explicit dereference in call ", N);
1878 -- If not an access to subprogram, then the prefix must resolve to the
1879 -- name of an entry, entry family, or protected operation.
1881 -- For the case of a simple entry call, P is a selected component where
1882 -- the prefix is the task and the selector name is the entry. A call to
1883 -- a protected procedure will have the same syntax. If the protected
1884 -- object contains overloaded operations, the entity may appear as a
1885 -- function, the context will select the operation whose type is Void.
1887 elsif Nkind (P) = N_Selected_Component
1888 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1892 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1893 -- in prefix notation may still be missing its controlling argument,
1894 -- so perform the transformation now.
1896 if SPARK_Mode = On and then In_Inlined_Body then
1898 Subp : constant Entity_Id := Entity (Selector_Name (P));
1899 Typ : constant Entity_Id := Etype (Prefix (P));
1902 if Is_Tagged_Type (Typ)
1903 and then Present (First_Formal (Subp))
1904 and then Etype (First_Formal (Subp)) = Typ
1905 and then Try_Object_Operation (P)
1910 Analyze_Call_And_Resolve;
1915 Analyze_Call_And_Resolve;
1918 elsif Nkind (P) = N_Selected_Component
1919 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1920 and then Present (Actuals)
1921 and then No (Next (First (Actuals)))
1923 -- Can be call to parameterless entry family. What appears to be the
1924 -- sole argument is in fact the entry index. Rewrite prefix of node
1925 -- accordingly. Source representation is unchanged by this
1929 Make_Indexed_Component (Loc,
1930 Prefix => New_Copy (P),
1931 Expressions => Actuals);
1932 Set_Name (N, New_N);
1933 Set_Etype (New_N, Standard_Void_Type);
1934 Set_Parameter_Associations (N, No_List);
1935 Analyze_Call_And_Resolve;
1937 -- For the case of a reference to an element of an entry family, P is
1938 -- an indexed component whose prefix is a selected component (task and
1939 -- entry family), and whose index is the entry family index.
1941 elsif Nkind (P) = N_Indexed_Component
1942 and then Nkind (Prefix (P)) = N_Selected_Component
1943 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1945 Analyze_Call_And_Resolve;
1947 -- If the prefix is the name of an entry family, it is a call from
1948 -- within the task body itself.
1950 elsif Nkind (P) = N_Indexed_Component
1951 and then Nkind (Prefix (P)) = N_Identifier
1952 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1955 Make_Selected_Component (Loc,
1956 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1957 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1958 Rewrite (Prefix (P), New_N);
1960 Analyze_Call_And_Resolve;
1962 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1963 -- procedure name, so the construct can only be a qualified expression.
1965 elsif Nkind (P) = N_Qualified_Expression
1966 and then Ada_Version >= Ada_2012
1968 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1971 -- Anything else is an error
1974 Error_Msg_N ("invalid procedure or entry call", N);
1978 Restore_Ghost_Mode (Saved_GM);
1979 end Analyze_Procedure_Call;
1981 ------------------------------
1982 -- Analyze_Return_Statement --
1983 ------------------------------
1985 procedure Analyze_Return_Statement (N : Node_Id) is
1986 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
1987 N_Simple_Return_Statement));
1989 Returns_Object : constant Boolean :=
1990 Nkind (N) = N_Extended_Return_Statement
1992 (Nkind (N) = N_Simple_Return_Statement
1993 and then Present (Expression (N)));
1994 -- True if we're returning something; that is, "return <expression>;"
1995 -- or "return Result : T [:= ...]". False for "return;". Used for error
1996 -- checking: If Returns_Object is True, N should apply to a function
1997 -- body; otherwise N should apply to a procedure body, entry body,
1998 -- accept statement, or extended return statement.
2000 function Find_What_It_Applies_To return Entity_Id;
2001 -- Find the entity representing the innermost enclosing body, accept
2002 -- statement, or extended return statement. If the result is a callable
2003 -- construct or extended return statement, then this will be the value
2004 -- of the Return_Applies_To attribute. Otherwise, the program is
2005 -- illegal. See RM-6.5(4/2).
2007 -----------------------------
2008 -- Find_What_It_Applies_To --
2009 -----------------------------
2011 function Find_What_It_Applies_To return Entity_Id is
2012 Result : Entity_Id := Empty;
2015 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2016 -- and postconditions.
2018 for J in reverse 0 .. Scope_Stack.Last loop
2019 Result := Scope_Stack.Table (J).Entity;
2020 exit when not Ekind_In (Result, E_Block, E_Loop)
2021 and then Chars (Result) /= Name_uPostconditions;
2024 pragma Assert (Present (Result));
2026 end Find_What_It_Applies_To;
2028 -- Local declarations
2030 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2031 Kind : constant Entity_Kind := Ekind (Scope_Id);
2032 Loc : constant Source_Ptr := Sloc (N);
2033 Stm_Entity : constant Entity_Id :=
2035 (E_Return_Statement, Current_Scope, Loc, 'R');
2037 -- Start of processing for Analyze_Return_Statement
2040 Set_Return_Statement_Entity (N, Stm_Entity);
2042 Set_Etype (Stm_Entity, Standard_Void_Type);
2043 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2045 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2046 -- (4/2): an inner return statement will apply to this extended return.
2048 if Nkind (N) = N_Extended_Return_Statement then
2049 Push_Scope (Stm_Entity);
2052 -- Check that pragma No_Return is obeyed. Don't complain about the
2053 -- implicitly-generated return that is placed at the end.
2055 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2056 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2059 -- Warn on any unassigned OUT parameters if in procedure
2061 if Ekind (Scope_Id) = E_Procedure then
2062 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2065 -- Check that functions return objects, and other things do not
2067 if Kind = E_Function or else Kind = E_Generic_Function then
2068 if not Returns_Object then
2069 Error_Msg_N ("missing expression in return from function", N);
2072 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2073 if Returns_Object then
2074 Error_Msg_N ("procedure cannot return value (use function)", N);
2077 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2078 if Returns_Object then
2079 if Is_Protected_Type (Scope (Scope_Id)) then
2080 Error_Msg_N ("entry body cannot return value", N);
2082 Error_Msg_N ("accept statement cannot return value", N);
2086 elsif Kind = E_Return_Statement then
2088 -- We are nested within another return statement, which must be an
2089 -- extended_return_statement.
2091 if Returns_Object then
2092 if Nkind (N) = N_Extended_Return_Statement then
2094 ("extended return statement cannot be nested (use `RETURN;`)",
2097 -- Case of a simple return statement with a value inside extended
2098 -- return statement.
2102 ("return nested in extended return statement cannot return "
2103 & "value (use `RETURN;`)", N);
2108 Error_Msg_N ("illegal context for return statement", N);
2111 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2112 Analyze_Function_Return (N);
2114 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2115 Set_Return_Present (Scope_Id);
2118 if Nkind (N) = N_Extended_Return_Statement then
2122 Kill_Current_Values (Last_Assignment_Only => True);
2123 Check_Unreachable_Code (N);
2125 Analyze_Dimension (N);
2126 end Analyze_Return_Statement;
2128 -------------------------------------
2129 -- Analyze_Simple_Return_Statement --
2130 -------------------------------------
2132 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2134 if Present (Expression (N)) then
2135 Mark_Coextensions (N, Expression (N));
2138 Analyze_Return_Statement (N);
2139 end Analyze_Simple_Return_Statement;
2141 -------------------------
2142 -- Analyze_Return_Type --
2143 -------------------------
2145 procedure Analyze_Return_Type (N : Node_Id) is
2146 Designator : constant Entity_Id := Defining_Entity (N);
2147 Typ : Entity_Id := Empty;
2150 -- Normal case where result definition does not indicate an error
2152 if Result_Definition (N) /= Error then
2153 if Nkind (Result_Definition (N)) = N_Access_Definition then
2154 Check_SPARK_05_Restriction
2155 ("access result is not allowed", Result_Definition (N));
2157 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2160 AD : constant Node_Id :=
2161 Access_To_Subprogram_Definition (Result_Definition (N));
2163 if Present (AD) and then Protected_Present (AD) then
2164 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2166 Typ := Access_Definition (N, Result_Definition (N));
2170 Set_Parent (Typ, Result_Definition (N));
2171 Set_Is_Local_Anonymous_Access (Typ);
2172 Set_Etype (Designator, Typ);
2174 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2176 Null_Exclusion_Static_Checks (N);
2178 -- Subtype_Mark case
2181 Find_Type (Result_Definition (N));
2182 Typ := Entity (Result_Definition (N));
2183 Set_Etype (Designator, Typ);
2185 -- Unconstrained array as result is not allowed in SPARK
2187 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2188 Check_SPARK_05_Restriction
2189 ("returning an unconstrained array is not allowed",
2190 Result_Definition (N));
2193 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2195 Null_Exclusion_Static_Checks (N);
2197 -- If a null exclusion is imposed on the result type, then create
2198 -- a null-excluding itype (an access subtype) and use it as the
2199 -- function's Etype. Note that the null exclusion checks are done
2200 -- right before this, because they don't get applied to types that
2201 -- do not come from source.
2203 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2204 Set_Etype (Designator,
2205 Create_Null_Excluding_Itype
2208 Scope_Id => Scope (Current_Scope)));
2210 -- The new subtype must be elaborated before use because
2211 -- it is visible outside of the function. However its base
2212 -- type may not be frozen yet, so the reference that will
2213 -- force elaboration must be attached to the freezing of
2216 -- If the return specification appears on a proper body,
2217 -- the subtype will have been created already on the spec.
2219 if Is_Frozen (Typ) then
2220 if Nkind (Parent (N)) = N_Subprogram_Body
2221 and then Nkind (Parent (Parent (N))) = N_Subunit
2225 Build_Itype_Reference (Etype (Designator), Parent (N));
2229 Ensure_Freeze_Node (Typ);
2232 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2234 Set_Itype (IR, Etype (Designator));
2235 Append_Freeze_Actions (Typ, New_List (IR));
2240 Set_Etype (Designator, Typ);
2243 if Ekind (Typ) = E_Incomplete_Type
2244 or else (Is_Class_Wide_Type (Typ)
2245 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2247 -- AI05-0151: Tagged incomplete types are allowed in all formal
2248 -- parts. Untagged incomplete types are not allowed in bodies.
2249 -- As a consequence, limited views cannot appear in a basic
2250 -- declaration that is itself within a body, because there is
2251 -- no point at which the non-limited view will become visible.
2253 if Ada_Version >= Ada_2012 then
2254 if From_Limited_With (Typ) and then In_Package_Body then
2256 ("invalid use of incomplete type&",
2257 Result_Definition (N), Typ);
2259 -- The return type of a subprogram body cannot be of a
2260 -- formal incomplete type.
2262 elsif Is_Generic_Type (Typ)
2263 and then Nkind (Parent (N)) = N_Subprogram_Body
2266 ("return type cannot be a formal incomplete type",
2267 Result_Definition (N));
2269 elsif Is_Class_Wide_Type (Typ)
2270 and then Is_Generic_Type (Root_Type (Typ))
2271 and then Nkind (Parent (N)) = N_Subprogram_Body
2274 ("return type cannot be a formal incomplete type",
2275 Result_Definition (N));
2277 elsif Is_Tagged_Type (Typ) then
2280 -- Use is legal in a thunk generated for an operation
2281 -- inherited from a progenitor.
2283 elsif Is_Thunk (Designator)
2284 and then Present (Non_Limited_View (Typ))
2288 elsif Nkind (Parent (N)) = N_Subprogram_Body
2289 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2293 ("invalid use of untagged incomplete type&",
2297 -- The type must be completed in the current package. This
2298 -- is checked at the end of the package declaration when
2299 -- Taft-amendment types are identified. If the return type
2300 -- is class-wide, there is no required check, the type can
2301 -- be a bona fide TAT.
2303 if Ekind (Scope (Current_Scope)) = E_Package
2304 and then In_Private_Part (Scope (Current_Scope))
2305 and then not Is_Class_Wide_Type (Typ)
2307 Append_Elmt (Designator, Private_Dependents (Typ));
2312 ("invalid use of incomplete type&", Designator, Typ);
2317 -- Case where result definition does indicate an error
2320 Set_Etype (Designator, Any_Type);
2322 end Analyze_Return_Type;
2324 -----------------------------
2325 -- Analyze_Subprogram_Body --
2326 -----------------------------
2328 procedure Analyze_Subprogram_Body (N : Node_Id) is
2329 Loc : constant Source_Ptr := Sloc (N);
2330 Body_Spec : constant Node_Id := Specification (N);
2331 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2334 if Debug_Flag_C then
2335 Write_Str ("==> subprogram body ");
2336 Write_Name (Chars (Body_Id));
2337 Write_Str (" from ");
2338 Write_Location (Loc);
2343 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2345 -- The real work is split out into the helper, so it can do "return;"
2346 -- without skipping the debug output:
2348 Analyze_Subprogram_Body_Helper (N);
2350 if Debug_Flag_C then
2352 Write_Str ("<== subprogram body ");
2353 Write_Name (Chars (Body_Id));
2354 Write_Str (" from ");
2355 Write_Location (Loc);
2358 end Analyze_Subprogram_Body;
2360 ------------------------------------
2361 -- Analyze_Subprogram_Body_Helper --
2362 ------------------------------------
2364 -- This procedure is called for regular subprogram bodies, generic bodies,
2365 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2366 -- specification matters, and is used to create a proper declaration for
2367 -- the subprogram, or to perform conformance checks.
2369 -- WARNING: This routine manages Ghost regions. Return statements must be
2370 -- replaced by gotos which jump to the end of the routine and restore the
2373 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2374 Body_Spec : Node_Id := Specification (N);
2375 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2376 Loc : constant Source_Ptr := Sloc (N);
2377 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2379 Conformant : Boolean;
2380 Desig_View : Entity_Id := Empty;
2381 Exch_Views : Elist_Id := No_Elist;
2383 Mask_Types : Elist_Id := No_Elist;
2384 Prot_Typ : Entity_Id := Empty;
2385 Spec_Decl : Node_Id := Empty;
2386 Spec_Id : Entity_Id;
2388 Last_Real_Spec_Entity : Entity_Id := Empty;
2389 -- When we analyze a separate spec, the entity chain ends up containing
2390 -- the formals, as well as any itypes generated during analysis of the
2391 -- default expressions for parameters, or the arguments of associated
2392 -- precondition/postcondition pragmas (which are analyzed in the context
2393 -- of the spec since they have visibility on formals).
2395 -- These entities belong with the spec and not the body. However we do
2396 -- the analysis of the body in the context of the spec (again to obtain
2397 -- visibility to the formals), and all the entities generated during
2398 -- this analysis end up also chained to the entity chain of the spec.
2399 -- But they really belong to the body, and there is circuitry to move
2400 -- them from the spec to the body.
2402 -- However, when we do this move, we don't want to move the real spec
2403 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2404 -- variable points to the last real spec entity, so we only move those
2405 -- chained beyond that point. It is initialized to Empty to deal with
2406 -- the case where there is no separate spec.
2408 function Body_Has_Contract return Boolean;
2409 -- Check whether unanalyzed body has an aspect or pragma that may
2410 -- generate a SPARK contract.
2412 function Body_Has_SPARK_Mode_On return Boolean;
2413 -- Check whether SPARK_Mode On applies to the subprogram body, either
2414 -- because it is specified directly on the body, or because it is
2415 -- inherited from the enclosing subprogram or package.
2417 procedure Build_Subprogram_Declaration;
2418 -- Create a matching subprogram declaration for subprogram body N
2420 procedure Check_Anonymous_Return;
2421 -- Ada 2005: if a function returns an access type that denotes a task,
2422 -- or a type that contains tasks, we must create a master entity for
2423 -- the anonymous type, which typically will be used in an allocator
2424 -- in the body of the function.
2426 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2427 -- Look ahead to recognize a pragma that may appear after the body.
2428 -- If there is a previous spec, check that it appears in the same
2429 -- declarative part. If the pragma is Inline_Always, perform inlining
2430 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2431 -- If the body acts as a spec, and inlining is required, we create a
2432 -- subprogram declaration for it, in order to attach the body to inline.
2433 -- If pragma does not appear after the body, check whether there is
2434 -- an inline pragma before any local declarations.
2436 procedure Check_Missing_Return;
2437 -- Checks for a function with a no return statements, and also performs
2438 -- the warning checks implemented by Check_Returns. In formal mode, also
2439 -- verify that a function ends with a RETURN and that a procedure does
2440 -- not contain any RETURN.
2442 function Disambiguate_Spec return Entity_Id;
2443 -- When a primitive is declared between the private view and the full
2444 -- view of a concurrent type which implements an interface, a special
2445 -- mechanism is used to find the corresponding spec of the primitive
2448 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2449 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2450 -- incomplete types coming from a limited context and replace their
2451 -- limited views with the non-limited ones. Return the list of changes
2452 -- to be used to undo the transformation.
2454 function Is_Private_Concurrent_Primitive
2455 (Subp_Id : Entity_Id) return Boolean;
2456 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2457 -- type that implements an interface and has a private view.
2459 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2460 -- N is the body generated for an expression function that is not a
2461 -- completion and Spec_Id the defining entity of its spec. Mark all
2462 -- the not-yet-frozen types referenced by the simple return statement
2463 -- of the function as formally frozen.
2465 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2466 -- Undo the transformation done by Exchange_Limited_Views.
2468 procedure Set_Trivial_Subprogram (N : Node_Id);
2469 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2470 -- subprogram whose body is being analyzed. N is the statement node
2471 -- causing the flag to be set, if the following statement is a return
2472 -- of an entity, we mark the entity as set in source to suppress any
2473 -- warning on the stylized use of function stubs with a dummy return.
2475 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2476 -- Undo the transformation done by Mask_Unfrozen_Types
2478 procedure Verify_Overriding_Indicator;
2479 -- If there was a previous spec, the entity has been entered in the
2480 -- current scope previously. If the body itself carries an overriding
2481 -- indicator, check that it is consistent with the known status of the
2484 -----------------------
2485 -- Body_Has_Contract --
2486 -----------------------
2488 function Body_Has_Contract return Boolean is
2489 Decls : constant List_Id := Declarations (N);
2493 -- Check for aspects that may generate a contract
2495 if Present (Aspect_Specifications (N)) then
2496 Item := First (Aspect_Specifications (N));
2497 while Present (Item) loop
2498 if Is_Subprogram_Contract_Annotation (Item) then
2506 -- Check for pragmas that may generate a contract
2508 if Present (Decls) then
2509 Item := First (Decls);
2510 while Present (Item) loop
2511 if Nkind (Item) = N_Pragma
2512 and then Is_Subprogram_Contract_Annotation (Item)
2522 end Body_Has_Contract;
2524 ----------------------------
2525 -- Body_Has_SPARK_Mode_On --
2526 ----------------------------
2528 function Body_Has_SPARK_Mode_On return Boolean is
2529 Decls : constant List_Id := Declarations (N);
2533 -- Check for SPARK_Mode aspect
2535 if Present (Aspect_Specifications (N)) then
2536 Item := First (Aspect_Specifications (N));
2537 while Present (Item) loop
2538 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2539 return Get_SPARK_Mode_From_Annotation (Item) = On;
2546 -- Check for SPARK_Mode pragma
2548 if Present (Decls) then
2549 Item := First (Decls);
2550 while Present (Item) loop
2552 -- Pragmas that apply to a subprogram body are usually grouped
2553 -- together. Look for a potential pragma SPARK_Mode among them.
2555 if Nkind (Item) = N_Pragma then
2556 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2557 return Get_SPARK_Mode_From_Annotation (Item) = On;
2560 -- Otherwise the first non-pragma declarative item terminates
2561 -- the region where pragma SPARK_Mode may appear.
2571 -- Otherwise, the applicable SPARK_Mode is inherited from the
2572 -- enclosing subprogram or package.
2574 return SPARK_Mode = On;
2575 end Body_Has_SPARK_Mode_On;
2577 ----------------------------------
2578 -- Build_Subprogram_Declaration --
2579 ----------------------------------
2581 procedure Build_Subprogram_Declaration is
2582 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2583 -- Relocate certain categorization pragmas from the declarative list
2584 -- of subprogram body From and insert them after node To. The pragmas
2587 -- Volatile_Function
2588 -- Also copy pragma SPARK_Mode if present in the declarative list
2589 -- of subprogram body From and insert it after node To. This pragma
2590 -- should not be moved, as it applies to the body too.
2596 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2598 Next_Decl : Node_Id;
2601 pragma Assert (Nkind (From) = N_Subprogram_Body);
2603 -- The destination node must be part of a list, as the pragmas are
2604 -- inserted after it.
2606 pragma Assert (Is_List_Member (To));
2608 -- Inspect the declarations of the subprogram body looking for
2609 -- specific pragmas.
2611 Decl := First (Declarations (N));
2612 while Present (Decl) loop
2613 Next_Decl := Next (Decl);
2615 if Nkind (Decl) = N_Pragma then
2616 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2617 Insert_After (To, New_Copy_Tree (Decl));
2619 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2621 Name_Volatile_Function)
2624 Insert_After (To, Decl);
2635 Subp_Decl : Node_Id;
2637 -- Start of processing for Build_Subprogram_Declaration
2640 -- Create a matching subprogram spec using the profile of the body.
2641 -- The structure of the tree is identical, but has new entities for
2642 -- the defining unit name and formal parameters.
2645 Make_Subprogram_Declaration (Loc,
2646 Specification => Copy_Subprogram_Spec (Body_Spec));
2647 Set_Comes_From_Source (Subp_Decl, True);
2649 -- Relocate the aspects and relevant pragmas from the subprogram body
2650 -- to the generated spec because it acts as the initial declaration.
2652 Insert_Before (N, Subp_Decl);
2653 Move_Aspects (N, To => Subp_Decl);
2654 Move_Pragmas (N, To => Subp_Decl);
2656 -- Ensure that the generated corresponding spec and original body
2657 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2658 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2659 -- correctly set for local subprograms.
2661 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2663 Analyze (Subp_Decl);
2665 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2666 -- the body since the expander may generate calls using that entity.
2667 -- Required to ensure that Expand_Call rewrites calls to this
2668 -- function by calls to the built procedure.
2670 if Modify_Tree_For_C
2671 and then Nkind (Body_Spec) = N_Function_Specification
2673 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2675 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2676 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2677 Corresponding_Procedure
2678 (Defining_Entity (Specification (Subp_Decl))));
2681 -- Analyze any relocated source pragmas or pragmas created for aspect
2684 Decl := Next (Subp_Decl);
2685 while Present (Decl) loop
2687 -- Stop the search for pragmas once the body has been reached as
2688 -- this terminates the region where pragmas may appear.
2693 elsif Nkind (Decl) = N_Pragma then
2700 Spec_Id := Defining_Entity (Subp_Decl);
2701 Set_Corresponding_Spec (N, Spec_Id);
2703 -- Mark the generated spec as a source construct to ensure that all
2704 -- calls to it are properly registered in ALI files for GNATprove.
2706 Set_Comes_From_Source (Spec_Id, True);
2708 -- Ensure that the specs of the subprogram declaration and its body
2709 -- are identical, otherwise they will appear non-conformant due to
2710 -- rewritings in the default values of formal parameters.
2712 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2713 Set_Specification (N, Body_Spec);
2714 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2715 end Build_Subprogram_Declaration;
2717 ----------------------------
2718 -- Check_Anonymous_Return --
2719 ----------------------------
2721 procedure Check_Anonymous_Return is
2727 if Present (Spec_Id) then
2733 if Ekind (Scop) = E_Function
2734 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2735 and then not Is_Thunk (Scop)
2737 -- Skip internally built functions which handle the case of
2738 -- a null access (see Expand_Interface_Conversion)
2740 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2741 and then not Comes_From_Source (Parent (Scop)))
2743 and then (Has_Task (Designated_Type (Etype (Scop)))
2745 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2747 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2748 and then Expander_Active
2750 -- Avoid cases with no tasking support
2752 and then RTE_Available (RE_Current_Master)
2753 and then not Restriction_Active (No_Task_Hierarchy)
2756 Make_Object_Declaration (Loc,
2757 Defining_Identifier =>
2758 Make_Defining_Identifier (Loc, Name_uMaster),
2759 Constant_Present => True,
2760 Object_Definition =>
2761 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2763 Make_Explicit_Dereference (Loc,
2764 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2766 if Present (Declarations (N)) then
2767 Prepend (Decl, Declarations (N));
2769 Set_Declarations (N, New_List (Decl));
2772 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2773 Set_Has_Master_Entity (Scop);
2775 -- Now mark the containing scope as a task master
2778 while Nkind (Par) /= N_Compilation_Unit loop
2779 Par := Parent (Par);
2780 pragma Assert (Present (Par));
2782 -- If we fall off the top, we are at the outer level, and
2783 -- the environment task is our effective master, so nothing
2787 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2789 Set_Is_Task_Master (Par, True);
2794 end Check_Anonymous_Return;
2796 -------------------------
2797 -- Check_Inline_Pragma --
2798 -------------------------
2800 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2804 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2805 -- True when N is a pragma Inline or Inline_Always that applies
2806 -- to this subprogram.
2808 -----------------------
2809 -- Is_Inline_Pragma --
2810 -----------------------
2812 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2814 if Nkind (N) = N_Pragma
2816 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2817 or else (Pragma_Name_Unmapped (N) = Name_Inline
2819 (Front_End_Inlining or else Optimization_Level > 0)))
2820 and then Present (Pragma_Argument_Associations (N))
2823 Pragma_Arg : Node_Id :=
2824 Expression (First (Pragma_Argument_Associations (N)));
2826 if Nkind (Pragma_Arg) = N_Selected_Component then
2827 Pragma_Arg := Selector_Name (Pragma_Arg);
2830 return Chars (Pragma_Arg) = Chars (Body_Id);
2836 end Is_Inline_Pragma;
2838 -- Start of processing for Check_Inline_Pragma
2841 if not Expander_Active then
2845 if Is_List_Member (N)
2846 and then Present (Next (N))
2847 and then Is_Inline_Pragma (Next (N))
2851 elsif Nkind (N) /= N_Subprogram_Body_Stub
2852 and then Present (Declarations (N))
2853 and then Is_Inline_Pragma (First (Declarations (N)))
2855 Prag := First (Declarations (N));
2861 if Present (Prag) then
2862 if Present (Spec_Id) then
2863 if Is_List_Member (N)
2864 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2865 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2871 -- Create a subprogram declaration, to make treatment uniform.
2872 -- Make the sloc of the subprogram name that of the entity in
2873 -- the body, so that style checks find identical strings.
2876 Subp : constant Entity_Id :=
2877 Make_Defining_Identifier
2878 (Sloc (Body_Id), Chars (Body_Id));
2879 Decl : constant Node_Id :=
2880 Make_Subprogram_Declaration (Loc,
2882 New_Copy_Tree (Specification (N)));
2885 Set_Defining_Unit_Name (Specification (Decl), Subp);
2887 -- To ensure proper coverage when body is inlined, indicate
2888 -- whether the subprogram comes from source.
2890 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2892 if Present (First_Formal (Body_Id)) then
2893 Plist := Copy_Parameter_List (Body_Id);
2894 Set_Parameter_Specifications
2895 (Specification (Decl), Plist);
2898 -- Move aspects to the new spec
2900 if Has_Aspects (N) then
2901 Move_Aspects (N, To => Decl);
2904 Insert_Before (N, Decl);
2907 Set_Has_Pragma_Inline (Subp);
2909 if Pragma_Name (Prag) = Name_Inline_Always then
2910 Set_Is_Inlined (Subp);
2911 Set_Has_Pragma_Inline_Always (Subp);
2914 -- Prior to copying the subprogram body to create a template
2915 -- for it for subsequent inlining, remove the pragma from
2916 -- the current body so that the copy that will produce the
2917 -- new body will start from a completely unanalyzed tree.
2919 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2920 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2927 end Check_Inline_Pragma;
2929 --------------------------
2930 -- Check_Missing_Return --
2931 --------------------------
2933 procedure Check_Missing_Return is
2935 Missing_Ret : Boolean;
2938 if Nkind (Body_Spec) = N_Function_Specification then
2939 if Present (Spec_Id) then
2945 if Return_Present (Id) then
2946 Check_Returns (HSS, 'F', Missing_Ret);
2949 Set_Has_Missing_Return (Id);
2952 -- Within a premature instantiation of a package with no body, we
2953 -- build completions of the functions therein, with a Raise
2954 -- statement. No point in complaining about a missing return in
2957 elsif Ekind (Id) = E_Function
2958 and then In_Instance
2959 and then Present (Statements (HSS))
2960 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2964 elsif Is_Generic_Subprogram (Id)
2965 or else not Is_Machine_Code_Subprogram (Id)
2967 Error_Msg_N ("missing RETURN statement in function body", N);
2970 -- If procedure with No_Return, check returns
2972 elsif Nkind (Body_Spec) = N_Procedure_Specification
2973 and then Present (Spec_Id)
2974 and then No_Return (Spec_Id)
2976 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2979 -- Special checks in SPARK mode
2981 if Nkind (Body_Spec) = N_Function_Specification then
2983 -- In SPARK mode, last statement of a function should be a return
2986 Stat : constant Node_Id := Last_Source_Statement (HSS);
2989 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2990 N_Extended_Return_Statement)
2992 Check_SPARK_05_Restriction
2993 ("last statement in function should be RETURN", Stat);
2997 -- In SPARK mode, verify that a procedure has no return
2999 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3000 if Present (Spec_Id) then
3006 -- Would be nice to point to return statement here, can we
3007 -- borrow the Check_Returns procedure here ???
3009 if Return_Present (Id) then
3010 Check_SPARK_05_Restriction
3011 ("procedure should not have RETURN", N);
3014 end Check_Missing_Return;
3016 -----------------------
3017 -- Disambiguate_Spec --
3018 -----------------------
3020 function Disambiguate_Spec return Entity_Id is
3021 Priv_Spec : Entity_Id;
3024 procedure Replace_Types (To_Corresponding : Boolean);
3025 -- Depending on the flag, replace the type of formal parameters of
3026 -- Body_Id if it is a concurrent type implementing interfaces with
3027 -- the corresponding record type or the other way around.
3029 procedure Replace_Types (To_Corresponding : Boolean) is
3031 Formal_Typ : Entity_Id;
3034 Formal := First_Formal (Body_Id);
3035 while Present (Formal) loop
3036 Formal_Typ := Etype (Formal);
3038 if Is_Class_Wide_Type (Formal_Typ) then
3039 Formal_Typ := Root_Type (Formal_Typ);
3042 -- From concurrent type to corresponding record
3044 if To_Corresponding then
3045 if Is_Concurrent_Type (Formal_Typ)
3046 and then Present (Corresponding_Record_Type (Formal_Typ))
3049 (Corresponding_Record_Type (Formal_Typ)))
3052 Corresponding_Record_Type (Formal_Typ));
3055 -- From corresponding record to concurrent type
3058 if Is_Concurrent_Record_Type (Formal_Typ)
3059 and then Present (Interfaces (Formal_Typ))
3062 Corresponding_Concurrent_Type (Formal_Typ));
3066 Next_Formal (Formal);
3070 -- Start of processing for Disambiguate_Spec
3073 -- Try to retrieve the specification of the body as is. All error
3074 -- messages are suppressed because the body may not have a spec in
3075 -- its current state.
3077 Spec_N := Find_Corresponding_Spec (N, False);
3079 -- It is possible that this is the body of a primitive declared
3080 -- between a private and a full view of a concurrent type. The
3081 -- controlling parameter of the spec carries the concurrent type,
3082 -- not the corresponding record type as transformed by Analyze_
3083 -- Subprogram_Specification. In such cases, we undo the change
3084 -- made by the analysis of the specification and try to find the
3087 -- Note that wrappers already have their corresponding specs and
3088 -- bodies set during their creation, so if the candidate spec is
3089 -- a wrapper, then we definitely need to swap all types to their
3090 -- original concurrent status.
3093 or else Is_Primitive_Wrapper (Spec_N)
3095 -- Restore all references of corresponding record types to the
3096 -- original concurrent types.
3098 Replace_Types (To_Corresponding => False);
3099 Priv_Spec := Find_Corresponding_Spec (N, False);
3101 -- The current body truly belongs to a primitive declared between
3102 -- a private and a full view. We leave the modified body as is,
3103 -- and return the true spec.
3105 if Present (Priv_Spec)
3106 and then Is_Private_Primitive (Priv_Spec)
3111 -- In case that this is some sort of error, restore the original
3112 -- state of the body.
3114 Replace_Types (To_Corresponding => True);
3118 end Disambiguate_Spec;
3120 ----------------------------
3121 -- Exchange_Limited_Views --
3122 ----------------------------
3124 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3125 Result : Elist_Id := No_Elist;
3127 procedure Detect_And_Exchange (Id : Entity_Id);
3128 -- Determine whether Id's type denotes an incomplete type associated
3129 -- with a limited with clause and exchange the limited view with the
3130 -- non-limited one when available. Note that the non-limited view
3131 -- may exist because of a with_clause in another unit in the context,
3132 -- but cannot be used because the current view of the enclosing unit
3133 -- is still a limited view.
3135 -------------------------
3136 -- Detect_And_Exchange --
3137 -------------------------
3139 procedure Detect_And_Exchange (Id : Entity_Id) is
3140 Typ : constant Entity_Id := Etype (Id);
3142 if From_Limited_With (Typ)
3143 and then Has_Non_Limited_View (Typ)
3144 and then not From_Limited_With (Scope (Typ))
3147 Result := New_Elmt_List;
3150 Prepend_Elmt (Typ, Result);
3151 Prepend_Elmt (Id, Result);
3152 Set_Etype (Id, Non_Limited_View (Typ));
3154 end Detect_And_Exchange;
3160 -- Start of processing for Exchange_Limited_Views
3163 -- Do not process subprogram bodies as they already use the non-
3164 -- limited view of types.
3166 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3170 -- Examine all formals and swap views when applicable
3172 Formal := First_Formal (Subp_Id);
3173 while Present (Formal) loop
3174 Detect_And_Exchange (Formal);
3176 Next_Formal (Formal);
3179 -- Process the return type of a function
3181 if Ekind (Subp_Id) = E_Function then
3182 Detect_And_Exchange (Subp_Id);
3186 end Exchange_Limited_Views;
3188 -------------------------------------
3189 -- Is_Private_Concurrent_Primitive --
3190 -------------------------------------
3192 function Is_Private_Concurrent_Primitive
3193 (Subp_Id : Entity_Id) return Boolean
3195 Formal_Typ : Entity_Id;
3198 if Present (First_Formal (Subp_Id)) then
3199 Formal_Typ := Etype (First_Formal (Subp_Id));
3201 if Is_Concurrent_Record_Type (Formal_Typ) then
3202 if Is_Class_Wide_Type (Formal_Typ) then
3203 Formal_Typ := Root_Type (Formal_Typ);
3206 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3209 -- The type of the first formal is a concurrent tagged type with
3213 Is_Concurrent_Type (Formal_Typ)
3214 and then Is_Tagged_Type (Formal_Typ)
3215 and then Has_Private_Declaration (Formal_Typ);
3219 end Is_Private_Concurrent_Primitive;
3221 -------------------------
3222 -- Mask_Unfrozen_Types --
3223 -------------------------
3225 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3226 Result : Elist_Id := No_Elist;
3228 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3229 -- Mask all types referenced in the subtree rooted at Node
3231 --------------------
3232 -- Mask_Type_Refs --
3233 --------------------
3235 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3236 procedure Mask_Type (Typ : Entity_Id);
3237 -- ??? what does this do?
3243 procedure Mask_Type (Typ : Entity_Id) is
3245 -- Skip Itypes created by the preanalysis
3248 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3253 if not Is_Frozen (Typ) then
3254 Set_Is_Frozen (Typ);
3255 Append_New_Elmt (Typ, Result);
3259 -- Start of processing for Mask_Type_Refs
3262 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3263 Mask_Type (Etype (Entity (Node)));
3265 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3266 Mask_Type (Scope (Entity (Node)));
3269 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3270 and then Present (Etype (Node))
3272 Mask_Type (Etype (Node));
3278 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3282 Return_Stmt : constant Node_Id :=
3283 First (Statements (Handled_Statement_Sequence (N)));
3285 -- Start of processing for Mask_Unfrozen_Types
3288 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3290 Mask_References (Expression (Return_Stmt));
3293 end Mask_Unfrozen_Types;
3295 ---------------------------
3296 -- Restore_Limited_Views --
3297 ---------------------------
3299 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3300 Elmt : Elmt_Id := First_Elmt (Restore_List);
3304 while Present (Elmt) loop
3307 Set_Etype (Id, Node (Elmt));
3310 end Restore_Limited_Views;
3312 ----------------------------
3313 -- Set_Trivial_Subprogram --
3314 ----------------------------
3316 procedure Set_Trivial_Subprogram (N : Node_Id) is
3317 Nxt : constant Node_Id := Next (N);
3320 Set_Is_Trivial_Subprogram (Body_Id);
3322 if Present (Spec_Id) then
3323 Set_Is_Trivial_Subprogram (Spec_Id);
3327 and then Nkind (Nxt) = N_Simple_Return_Statement
3328 and then No (Next (Nxt))
3329 and then Present (Expression (Nxt))
3330 and then Is_Entity_Name (Expression (Nxt))
3332 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3334 end Set_Trivial_Subprogram;
3336 ---------------------------
3337 -- Unmask_Unfrozen_Types --
3338 ---------------------------
3340 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3341 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3344 while Present (Elmt) loop
3345 Set_Is_Frozen (Node (Elmt), False);
3348 end Unmask_Unfrozen_Types;
3350 ---------------------------------
3351 -- Verify_Overriding_Indicator --
3352 ---------------------------------
3354 procedure Verify_Overriding_Indicator is
3356 if Must_Override (Body_Spec) then
3357 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3358 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3362 elsif not Present (Overridden_Operation (Spec_Id)) then
3364 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3366 -- Overriding indicators aren't allowed for protected subprogram
3367 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3368 -- this to a warning if -gnatd.E is enabled.
3370 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3371 Error_Msg_Warn := Error_To_Warning;
3373 ("<<overriding indicator not allowed for protected "
3374 & "subprogram body", Body_Spec);
3377 elsif Must_Not_Override (Body_Spec) then
3378 if Present (Overridden_Operation (Spec_Id)) then
3380 ("subprogram& overrides inherited operation",
3381 Body_Spec, Spec_Id);
3383 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3384 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3387 ("subprogram& overrides predefined operator ",
3388 Body_Spec, Spec_Id);
3390 -- Overriding indicators aren't allowed for protected subprogram
3391 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3392 -- this to a warning if -gnatd.E is enabled.
3394 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3395 Error_Msg_Warn := Error_To_Warning;
3398 ("<<overriding indicator not allowed "
3399 & "for protected subprogram body", Body_Spec);
3401 -- If this is not a primitive operation, then the overriding
3402 -- indicator is altogether illegal.
3404 elsif not Is_Primitive (Spec_Id) then
3406 ("overriding indicator only allowed "
3407 & "if subprogram is primitive", Body_Spec);
3410 -- If checking the style rule and the operation overrides, then
3411 -- issue a warning about a missing overriding_indicator. Protected
3412 -- subprogram bodies are excluded from this style checking, since
3413 -- they aren't primitives (even though their declarations can
3414 -- override) and aren't allowed to have an overriding_indicator.
3417 and then Present (Overridden_Operation (Spec_Id))
3418 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3420 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3421 Style.Missing_Overriding (N, Body_Id);
3424 and then Can_Override_Operator (Spec_Id)
3425 and then not In_Predefined_Unit (Spec_Id)
3427 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3428 Style.Missing_Overriding (N, Body_Id);
3430 end Verify_Overriding_Indicator;
3434 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3435 Saved_ISMP : constant Boolean :=
3436 Ignore_SPARK_Mode_Pragmas_In_Instance;
3437 -- Save the Ghost and SPARK mode-related data to restore on exit
3439 -- Start of processing for Analyze_Subprogram_Body_Helper
3442 -- A [generic] subprogram body "freezes" the contract of the nearest
3443 -- enclosing package body and all other contracts encountered in the
3444 -- same declarative part up to and excluding the subprogram body:
3446 -- package body Nearest_Enclosing_Package
3447 -- with Refined_State => (State => Constit)
3451 -- procedure Freezes_Enclosing_Package_Body
3452 -- with Refined_Depends => (Input => Constit) ...
3454 -- This ensures that any annotations referenced by the contract of the
3455 -- [generic] subprogram body are available. This form of "freezing" is
3456 -- decoupled from the usual Freeze_xxx mechanism because it must also
3457 -- work in the context of generics where normal freezing is disabled.
3459 -- Only bodies coming from source should cause this type of "freezing".
3460 -- Expression functions that act as bodies and complete an initial
3461 -- declaration must be included in this category, hence the use of
3464 if Comes_From_Source (Original_Node (N)) then
3465 Analyze_Previous_Contracts (N);
3468 -- Generic subprograms are handled separately. They always have a
3469 -- generic specification. Determine whether current scope has a
3470 -- previous declaration.
3472 -- If the subprogram body is defined within an instance of the same
3473 -- name, the instance appears as a package renaming, and will be hidden
3474 -- within the subprogram.
3476 if Present (Prev_Id)
3477 and then not Is_Overloadable (Prev_Id)
3478 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3479 or else Comes_From_Source (Prev_Id))
3481 if Is_Generic_Subprogram (Prev_Id) then
3484 -- A subprogram body is Ghost when it is stand alone and subject
3485 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3486 -- the mode now to ensure that any nodes generated during analysis
3487 -- and expansion are properly marked as Ghost.
3489 Mark_And_Set_Ghost_Body (N, Spec_Id);
3491 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3492 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3494 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3496 if Nkind (N) = N_Subprogram_Body then
3497 HSS := Handled_Statement_Sequence (N);
3498 Check_Missing_Return;
3503 -- Otherwise a previous entity conflicts with the subprogram name.
3504 -- Attempting to enter name will post error.
3507 Enter_Name (Body_Id);
3511 -- Non-generic case, find the subprogram declaration, if one was seen,
3512 -- or enter new overloaded entity in the current scope. If the
3513 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3514 -- part of the context of one of its subunits. No need to redo the
3517 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3521 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3523 if Nkind (N) = N_Subprogram_Body_Stub
3524 or else No (Corresponding_Spec (N))
3526 if Is_Private_Concurrent_Primitive (Body_Id) then
3527 Spec_Id := Disambiguate_Spec;
3529 -- A subprogram body is Ghost when it is stand alone and
3530 -- subject to pragma Ghost or when the corresponding spec is
3531 -- Ghost. Set the mode now to ensure that any nodes generated
3532 -- during analysis and expansion are properly marked as Ghost.
3534 Mark_And_Set_Ghost_Body (N, Spec_Id);
3537 Spec_Id := Find_Corresponding_Spec (N);
3539 -- A subprogram body is Ghost when it is stand alone and
3540 -- subject to pragma Ghost or when the corresponding spec is
3541 -- Ghost. Set the mode now to ensure that any nodes generated
3542 -- during analysis and expansion are properly marked as Ghost.
3544 Mark_And_Set_Ghost_Body (N, Spec_Id);
3546 -- In GNATprove mode, if the body has no previous spec, create
3547 -- one so that the inlining machinery can operate properly.
3548 -- Transfer aspects, if any, to the new spec, so that they
3549 -- are legal and can be processed ahead of the body.
3550 -- We make two copies of the given spec, one for the new
3551 -- declaration, and one for the body.
3553 if No (Spec_Id) and then GNATprove_Mode
3555 -- Inlining does not apply during pre-analysis of code
3557 and then Full_Analysis
3559 -- Inlining only applies to full bodies, not stubs
3561 and then Nkind (N) /= N_Subprogram_Body_Stub
3563 -- Inlining only applies to bodies in the source code, not to
3564 -- those generated by the compiler. In particular, expression
3565 -- functions, whose body is generated by the compiler, are
3566 -- treated specially by GNATprove.
3568 and then Comes_From_Source (Body_Id)
3570 -- This cannot be done for a compilation unit, which is not
3571 -- in a context where we can insert a new spec.
3573 and then Is_List_Member (N)
3575 -- Inlining only applies to subprograms without contracts,
3576 -- as a contract is a sign that GNATprove should perform a
3577 -- modular analysis of the subprogram instead of a contextual
3578 -- analysis at each call site. The same test is performed in
3579 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3580 -- here in another form (because the contract has not been
3581 -- attached to the body) to avoid front-end errors in case
3582 -- pragmas are used instead of aspects, because the
3583 -- corresponding pragmas in the body would not be transferred
3584 -- to the spec, leading to legality errors.
3586 and then not Body_Has_Contract
3587 and then not Inside_A_Generic
3589 Build_Subprogram_Declaration;
3591 -- If this is a function that returns a constrained array, and
3592 -- we are generating SPARK_For_C, create subprogram declaration
3593 -- to simplify subsequent C generation.
3596 and then Modify_Tree_For_C
3597 and then Nkind (Body_Spec) = N_Function_Specification
3598 and then Is_Array_Type (Etype (Body_Id))
3599 and then Is_Constrained (Etype (Body_Id))
3601 Build_Subprogram_Declaration;
3605 -- If this is a duplicate body, no point in analyzing it
3607 if Error_Posted (N) then
3611 -- A subprogram body should cause freezing of its own declaration,
3612 -- but if there was no previous explicit declaration, then the
3613 -- subprogram will get frozen too late (there may be code within
3614 -- the body that depends on the subprogram having been frozen,
3615 -- such as uses of extra formals), so we force it to be frozen
3616 -- here. Same holds if the body and spec are compilation units.
3617 -- Finally, if the return type is an anonymous access to protected
3618 -- subprogram, it must be frozen before the body because its
3619 -- expansion has generated an equivalent type that is used when
3620 -- elaborating the body.
3622 -- An exception in the case of Ada 2012, AI05-177: The bodies
3623 -- created for expression functions do not freeze.
3626 and then Nkind (Original_Node (N)) /= N_Expression_Function
3628 Freeze_Before (N, Body_Id);
3630 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3631 Freeze_Before (N, Spec_Id);
3633 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3634 Freeze_Before (N, Etype (Body_Id));
3638 Spec_Id := Corresponding_Spec (N);
3640 -- A subprogram body is Ghost when it is stand alone and subject
3641 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3642 -- the mode now to ensure that any nodes generated during analysis
3643 -- and expansion are properly marked as Ghost.
3645 Mark_And_Set_Ghost_Body (N, Spec_Id);
3649 -- Previously we scanned the body to look for nested subprograms, and
3650 -- rejected an inline directive if nested subprograms were present,
3651 -- because the back-end would generate conflicting symbols for the
3652 -- nested bodies. This is now unnecessary.
3654 -- Look ahead to recognize a pragma Inline that appears after the body
3656 Check_Inline_Pragma (Spec_Id);
3658 -- Deal with special case of a fully private operation in the body of
3659 -- the protected type. We must create a declaration for the subprogram,
3660 -- in order to attach the protected subprogram that will be used in
3661 -- internal calls. We exclude compiler generated bodies from the
3662 -- expander since the issue does not arise for those cases.
3665 and then Comes_From_Source (N)
3666 and then Is_Protected_Type (Current_Scope)
3668 Spec_Id := Build_Private_Protected_Declaration (N);
3671 -- If we are generating C and this is a function returning a constrained
3672 -- array type for which we must create a procedure with an extra out
3673 -- parameter, build and analyze the body now. The procedure declaration
3674 -- has already been created. We reuse the source body of the function,
3675 -- because in an instance it may contain global references that cannot
3676 -- be reanalyzed. The source function itself is not used any further,
3677 -- so we mark it as having a completion. If the subprogram is a stub the
3678 -- transformation is done later, when the proper body is analyzed.
3681 and then Modify_Tree_For_C
3682 and then Present (Spec_Id)
3683 and then Ekind (Spec_Id) = E_Function
3684 and then Nkind (N) /= N_Subprogram_Body_Stub
3685 and then Rewritten_For_C (Spec_Id)
3687 Set_Has_Completion (Spec_Id);
3689 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3692 -- The entity for the created procedure must remain invisible, so it
3693 -- does not participate in resolution of subsequent references to the
3696 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3700 -- If a separate spec is present, then deal with freezing issues
3702 if Present (Spec_Id) then
3703 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3704 Verify_Overriding_Indicator;
3706 -- In general, the spec will be frozen when we start analyzing the
3707 -- body. However, for internally generated operations, such as
3708 -- wrapper functions for inherited operations with controlling
3709 -- results, the spec may not have been frozen by the time we expand
3710 -- the freeze actions that include the bodies. In particular, extra
3711 -- formals for accessibility or for return-in-place may need to be
3712 -- generated. Freeze nodes, if any, are inserted before the current
3713 -- body. These freeze actions are also needed in ASIS mode and in
3714 -- Compile_Only mode to enable the proper back-end type annotations.
3715 -- They are necessary in any case to insure order of elaboration
3718 if not Is_Frozen (Spec_Id)
3719 and then (Expander_Active
3721 or else (Operating_Mode = Check_Semantics
3722 and then Serious_Errors_Detected = 0))
3724 -- The body generated for an expression function that is not a
3725 -- completion is a freeze point neither for the profile nor for
3726 -- anything else. That's why, in order to prevent any freezing
3727 -- during analysis, we need to mask types declared outside the
3728 -- expression that are not yet frozen.
3730 if Nkind (N) = N_Subprogram_Body
3731 and then Was_Expression_Function (N)
3732 and then not Has_Completion (Spec_Id)
3734 Set_Is_Frozen (Spec_Id);
3735 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3737 Set_Has_Delayed_Freeze (Spec_Id);
3738 Freeze_Before (N, Spec_Id);
3743 -- If the subprogram has a class-wide clone, build its body as a copy
3744 -- of the original body, and rewrite body of original subprogram as a
3745 -- wrapper that calls the clone.
3747 if Present (Spec_Id)
3748 and then Present (Class_Wide_Clone (Spec_Id))
3749 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3751 Build_Class_Wide_Clone_Body (Spec_Id, N);
3753 -- This is the new body for the existing primitive operation
3755 Rewrite (N, Build_Class_Wide_Clone_Call
3756 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3757 Set_Has_Completion (Spec_Id, False);
3762 -- Place subprogram on scope stack, and make formals visible. If there
3763 -- is a spec, the visible entity remains that of the spec.
3765 if Present (Spec_Id) then
3766 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3768 if Is_Child_Unit (Spec_Id) then
3769 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3773 Style.Check_Identifier (Body_Id, Spec_Id);
3776 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3777 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3779 if Is_Abstract_Subprogram (Spec_Id) then
3780 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3784 Set_Convention (Body_Id, Convention (Spec_Id));
3785 Set_Has_Completion (Spec_Id);
3787 if Is_Protected_Type (Scope (Spec_Id)) then
3788 Prot_Typ := Scope (Spec_Id);
3791 -- If this is a body generated for a renaming, do not check for
3792 -- full conformance. The check is redundant, because the spec of
3793 -- the body is a copy of the spec in the renaming declaration,
3794 -- and the test can lead to spurious errors on nested defaults.
3796 if Present (Spec_Decl)
3797 and then not Comes_From_Source (N)
3799 (Nkind (Original_Node (Spec_Decl)) =
3800 N_Subprogram_Renaming_Declaration
3801 or else (Present (Corresponding_Body (Spec_Decl))
3803 Nkind (Unit_Declaration_Node
3804 (Corresponding_Body (Spec_Decl))) =
3805 N_Subprogram_Renaming_Declaration))
3809 -- Conversely, the spec may have been generated for specless body
3810 -- with an inline pragma. The entity comes from source, which is
3811 -- both semantically correct and necessary for proper inlining.
3812 -- The subprogram declaration itself is not in the source.
3814 elsif Comes_From_Source (N)
3815 and then Present (Spec_Decl)
3816 and then not Comes_From_Source (Spec_Decl)
3817 and then Has_Pragma_Inline (Spec_Id)
3824 Fully_Conformant, True, Conformant, Body_Id);
3827 -- If the body is not fully conformant, we have to decide if we
3828 -- should analyze it or not. If it has a really messed up profile
3829 -- then we probably should not analyze it, since we will get too
3830 -- many bogus messages.
3832 -- Our decision is to go ahead in the non-fully conformant case
3833 -- only if it is at least mode conformant with the spec. Note
3834 -- that the call to Check_Fully_Conformant has issued the proper
3835 -- error messages to complain about the lack of conformance.
3838 and then not Mode_Conformant (Body_Id, Spec_Id)
3844 if Spec_Id /= Body_Id then
3845 Reference_Body_Formals (Spec_Id, Body_Id);
3848 Set_Ekind (Body_Id, E_Subprogram_Body);
3850 if Nkind (N) = N_Subprogram_Body_Stub then
3851 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3856 Set_Corresponding_Spec (N, Spec_Id);
3858 -- Ada 2005 (AI-345): If the operation is a primitive operation
3859 -- of a concurrent type, the type of the first parameter has been
3860 -- replaced with the corresponding record, which is the proper
3861 -- run-time structure to use. However, within the body there may
3862 -- be uses of the formals that depend on primitive operations
3863 -- of the type (in particular calls in prefixed form) for which
3864 -- we need the original concurrent type. The operation may have
3865 -- several controlling formals, so the replacement must be done
3868 if Comes_From_Source (Spec_Id)
3869 and then Present (First_Entity (Spec_Id))
3870 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3871 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3872 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3873 and then Present (Corresponding_Concurrent_Type
3874 (Etype (First_Entity (Spec_Id))))
3877 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3881 Form := First_Formal (Spec_Id);
3882 while Present (Form) loop
3883 if Etype (Form) = Typ then
3884 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3892 -- Make the formals visible, and place subprogram on scope stack.
3893 -- This is also the point at which we set Last_Real_Spec_Entity
3894 -- to mark the entities which will not be moved to the body.
3896 Install_Formals (Spec_Id);
3897 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3899 -- Within an instance, add local renaming declarations so that
3900 -- gdb can retrieve the values of actuals more easily. This is
3901 -- only relevant if generating code (and indeed we definitely
3902 -- do not want these definitions -gnatc mode, because that would
3905 if Is_Generic_Instance (Spec_Id)
3906 and then Is_Wrapper_Package (Current_Scope)
3907 and then Expander_Active
3909 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3912 Push_Scope (Spec_Id);
3914 -- Make sure that the subprogram is immediately visible. For
3915 -- child units that have no separate spec this is indispensable.
3916 -- Otherwise it is safe albeit redundant.
3918 Set_Is_Immediately_Visible (Spec_Id);
3921 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3922 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3923 Set_Scope (Body_Id, Scope (Spec_Id));
3925 -- Case of subprogram body with no previous spec
3928 -- Check for style warning required
3932 -- Only apply check for source level subprograms for which checks
3933 -- have not been suppressed.
3935 and then Comes_From_Source (Body_Id)
3936 and then not Suppress_Style_Checks (Body_Id)
3938 -- No warnings within an instance
3940 and then not In_Instance
3942 -- No warnings for expression functions
3944 and then Nkind (Original_Node (N)) /= N_Expression_Function
3946 Style.Body_With_No_Spec (N);
3949 New_Overloaded_Entity (Body_Id);
3951 if Nkind (N) /= N_Subprogram_Body_Stub then
3952 Set_Acts_As_Spec (N);
3953 Generate_Definition (Body_Id);
3955 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3957 -- If the body is an entry wrapper created for an entry with
3958 -- preconditions, it must be compiled in the context of the
3959 -- enclosing synchronized object, because it may mention other
3960 -- operations of the type.
3962 if Is_Entry_Wrapper (Body_Id) then
3964 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3967 Install_Declarations (Prot);
3971 Install_Formals (Body_Id);
3973 Push_Scope (Body_Id);
3976 -- For stubs and bodies with no previous spec, generate references to
3979 Generate_Reference_To_Formals (Body_Id);
3982 -- Entry barrier functions are generated outside the protected type and
3983 -- should not carry the SPARK_Mode of the enclosing context.
3985 if Nkind (N) = N_Subprogram_Body
3986 and then Is_Entry_Barrier_Function (N)
3990 -- The body is generated as part of expression function expansion. When
3991 -- the expression function appears in the visible declarations of a
3992 -- package, the body is added to the private declarations. Since both
3993 -- declarative lists may be subject to a different SPARK_Mode, inherit
3994 -- the mode of the spec.
3996 -- package P with SPARK_Mode is
3997 -- function Expr_Func ... is (...); -- original
3998 -- [function Expr_Func ...;] -- generated spec
4001 -- pragma SPARK_Mode (Off);
4002 -- [function Expr_Func ... is return ...;] -- generated body
4003 -- end P; -- mode is ON
4005 elsif not Comes_From_Source (N)
4006 and then Present (Spec_Id)
4007 and then Is_Expression_Function (Spec_Id)
4009 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4010 Set_SPARK_Pragma_Inherited
4011 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4013 -- Set the SPARK_Mode from the current context (may be overwritten later
4014 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4015 -- initially on a stand-alone subprogram body, but is then relocated to
4016 -- a generated corresponding spec. In this scenario the mode is shared
4017 -- between the spec and body.
4019 elsif No (SPARK_Pragma (Body_Id)) then
4020 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4021 Set_SPARK_Pragma_Inherited (Body_Id);
4024 -- A subprogram body may be instantiated or inlined at a later pass.
4025 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4026 -- applied to the initial declaration of the body.
4028 if Present (Spec_Id) then
4029 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4030 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4034 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4035 -- case the body is instantiated or inlined later and out of context.
4036 -- The body uses this attribute to restore the value of the global
4039 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4040 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4042 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4043 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4047 -- If this is the proper body of a stub, we must verify that the stub
4048 -- conforms to the body, and to the previous spec if one was present.
4049 -- We know already that the body conforms to that spec. This test is
4050 -- only required for subprograms that come from source.
4052 if Nkind (Parent (N)) = N_Subunit
4053 and then Comes_From_Source (N)
4054 and then not Error_Posted (Body_Id)
4055 and then Nkind (Corresponding_Stub (Parent (N))) =
4056 N_Subprogram_Body_Stub
4059 Old_Id : constant Entity_Id :=
4061 (Specification (Corresponding_Stub (Parent (N))));
4063 Conformant : Boolean := False;
4066 if No (Spec_Id) then
4067 Check_Fully_Conformant (Body_Id, Old_Id);
4071 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4073 if not Conformant then
4075 -- The stub was taken to be a new declaration. Indicate that
4078 Set_Has_Completion (Old_Id, False);
4084 Set_Has_Completion (Body_Id);
4085 Check_Eliminated (Body_Id);
4087 -- Analyze any aspect specifications that appear on the subprogram body
4088 -- stub. Stop the analysis now as the stub does not have a declarative
4089 -- or a statement part, and it cannot be inlined.
4091 if Nkind (N) = N_Subprogram_Body_Stub then
4092 if Has_Aspects (N) then
4093 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4101 -- Note: Normally we don't do any inlining if expansion is off, since
4102 -- we won't generate code in any case. An exception arises in GNATprove
4103 -- mode where we want to expand some calls in place, even with expansion
4104 -- disabled, since the inlining eases formal verification.
4106 if not GNATprove_Mode
4107 and then Expander_Active
4108 and then Serious_Errors_Detected = 0
4109 and then Present (Spec_Id)
4110 and then Has_Pragma_Inline (Spec_Id)
4112 -- Legacy implementation (relying on front-end inlining)
4114 if not Back_End_Inlining then
4115 if (Has_Pragma_Inline_Always (Spec_Id)
4116 and then not Opt.Disable_FE_Inline_Always)
4117 or else (Front_End_Inlining
4118 and then not Opt.Disable_FE_Inline)
4120 Build_Body_To_Inline (N, Spec_Id);
4123 -- New implementation (relying on back-end inlining)
4126 if Has_Pragma_Inline_Always (Spec_Id)
4127 or else Optimization_Level > 0
4129 -- Handle function returning an unconstrained type
4131 if Comes_From_Source (Body_Id)
4132 and then Ekind (Spec_Id) = E_Function
4133 and then Returns_Unconstrained_Type (Spec_Id)
4135 -- If function builds in place, i.e. returns a limited type,
4136 -- inlining cannot be done.
4138 and then not Is_Limited_Type (Etype (Spec_Id))
4140 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4144 Subp_Body : constant Node_Id :=
4145 Unit_Declaration_Node (Body_Id);
4146 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4149 -- Do not pass inlining to the backend if the subprogram
4150 -- has declarations or statements which cannot be inlined
4151 -- by the backend. This check is done here to emit an
4152 -- error instead of the generic warning message reported
4153 -- by the GCC backend (ie. "function might not be
4156 if Present (Subp_Decl)
4157 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4161 elsif Has_Excluded_Statement
4164 (Handled_Statement_Sequence (Subp_Body)))
4168 -- If the backend inlining is available then at this
4169 -- stage we only have to mark the subprogram as inlined.
4170 -- The expander will take care of registering it in the
4171 -- table of subprograms inlined by the backend a part of
4172 -- processing calls to it (cf. Expand_Call)
4175 Set_Is_Inlined (Spec_Id);
4182 -- In GNATprove mode, inline only when there is a separate subprogram
4183 -- declaration for now, as inlining of subprogram bodies acting as
4184 -- declarations, or subprogram stubs, are not supported by front-end
4185 -- inlining. This inlining should occur after analysis of the body, so
4186 -- that it is known whether the value of SPARK_Mode, which can be
4187 -- defined by a pragma inside the body, is applicable to the body.
4188 -- Inlining can be disabled with switch -gnatdm
4190 elsif GNATprove_Mode
4191 and then Full_Analysis
4192 and then not Inside_A_Generic
4193 and then Present (Spec_Id)
4195 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4196 and then Body_Has_SPARK_Mode_On
4197 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4198 and then not Body_Has_Contract
4199 and then not Debug_Flag_M
4201 Build_Body_To_Inline (N, Spec_Id);
4204 -- When generating code, inherited pre/postconditions are handled when
4205 -- expanding the corresponding contract.
4207 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4208 -- of the specification we have to install the private withed units.
4209 -- This holds for child units as well.
4211 if Is_Compilation_Unit (Body_Id)
4212 or else Nkind (Parent (N)) = N_Compilation_Unit
4214 Install_Private_With_Clauses (Body_Id);
4217 Check_Anonymous_Return;
4219 -- Set the Protected_Formal field of each extra formal of the protected
4220 -- subprogram to reference the corresponding extra formal of the
4221 -- subprogram that implements it. For regular formals this occurs when
4222 -- the protected subprogram's declaration is expanded, but the extra
4223 -- formals don't get created until the subprogram is frozen. We need to
4224 -- do this before analyzing the protected subprogram's body so that any
4225 -- references to the original subprogram's extra formals will be changed
4226 -- refer to the implementing subprogram's formals (see Expand_Formal).
4228 if Present (Spec_Id)
4229 and then Is_Protected_Type (Scope (Spec_Id))
4230 and then Present (Protected_Body_Subprogram (Spec_Id))
4233 Impl_Subp : constant Entity_Id :=
4234 Protected_Body_Subprogram (Spec_Id);
4235 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4236 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4239 while Present (Prot_Ext_Formal) loop
4240 pragma Assert (Present (Impl_Ext_Formal));
4241 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4242 Next_Formal_With_Extras (Prot_Ext_Formal);
4243 Next_Formal_With_Extras (Impl_Ext_Formal);
4248 -- Now we can go on to analyze the body
4250 HSS := Handled_Statement_Sequence (N);
4251 Set_Actual_Subtypes (N, Current_Scope);
4253 -- Add a declaration for the Protection object, renaming declarations
4254 -- for discriminals and privals and finally a declaration for the entry
4255 -- family index (if applicable). This form of early expansion is done
4256 -- when the Expander is active because Install_Private_Data_Declarations
4257 -- references entities which were created during regular expansion. The
4258 -- subprogram entity must come from source, and not be an internally
4259 -- generated subprogram.
4262 and then Present (Prot_Typ)
4263 and then Present (Spec_Id)
4264 and then Comes_From_Source (Spec_Id)
4265 and then not Is_Eliminated (Spec_Id)
4267 Install_Private_Data_Declarations
4268 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4271 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4272 -- may now appear in parameter and result profiles. Since the analysis
4273 -- of a subprogram body may use the parameter and result profile of the
4274 -- spec, swap any limited views with their non-limited counterpart.
4276 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4277 Exch_Views := Exchange_Limited_Views (Spec_Id);
4280 -- If the return type is an anonymous access type whose designated type
4281 -- is the limited view of a class-wide type and the non-limited view is
4282 -- available, update the return type accordingly.
4284 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4290 Rtyp := Etype (Spec_Id);
4292 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4293 Etyp := Directly_Designated_Type (Rtyp);
4295 if Is_Class_Wide_Type (Etyp)
4296 and then From_Limited_With (Etyp)
4299 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4305 -- Analyze any aspect specifications that appear on the subprogram body
4307 if Has_Aspects (N) then
4308 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4311 Analyze_Declarations (Declarations (N));
4313 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4315 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4316 if Present (SPARK_Pragma (Spec_Id)) then
4317 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4319 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4321 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4322 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4323 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4325 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4328 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4332 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4333 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4334 Error_Msg_Sloc := Sloc (Spec_Id);
4336 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4340 -- A subprogram body "freezes" its own contract. Analyze the contract
4341 -- after the declarations of the body have been processed as pragmas
4342 -- are now chained on the contract of the subprogram body.
4344 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4346 -- Check completion, and analyze the statements
4349 Inspect_Deferred_Constant_Completion (Declarations (N));
4352 -- Deal with end of scope processing for the body
4354 Process_End_Label (HSS, 't', Current_Scope);
4357 -- If we are compiling an entry wrapper, remove the enclosing
4358 -- synchronized object from the stack.
4360 if Is_Entry_Wrapper (Body_Id) then
4364 Check_Subprogram_Order (N);
4365 Set_Analyzed (Body_Id);
4367 -- If we have a separate spec, then the analysis of the declarations
4368 -- caused the entities in the body to be chained to the spec id, but
4369 -- we want them chained to the body id. Only the formal parameters
4370 -- end up chained to the spec id in this case.
4372 if Present (Spec_Id) then
4374 -- We must conform to the categorization of our spec
4376 Validate_Categorization_Dependency (N, Spec_Id);
4378 -- And if this is a child unit, the parent units must conform
4380 if Is_Child_Unit (Spec_Id) then
4381 Validate_Categorization_Dependency
4382 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4385 -- Here is where we move entities from the spec to the body
4387 -- Case where there are entities that stay with the spec
4389 if Present (Last_Real_Spec_Entity) then
4391 -- No body entities (happens when the only real spec entities come
4392 -- from precondition and postcondition pragmas).
4394 if No (Last_Entity (Body_Id)) then
4395 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4397 -- Body entities present (formals), so chain stuff past them
4401 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4404 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4405 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4406 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4408 -- Case where there are no spec entities, in this case there can be
4409 -- no body entities either, so just move everything.
4411 -- If the body is generated for an expression function, it may have
4412 -- been preanalyzed already, if 'access was applied to it.
4415 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4416 N_Expression_Function
4418 pragma Assert (No (Last_Entity (Body_Id)));
4422 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4423 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4424 Set_First_Entity (Spec_Id, Empty);
4425 Set_Last_Entity (Spec_Id, Empty);
4429 Check_Missing_Return;
4431 -- Now we are going to check for variables that are never modified in
4432 -- the body of the procedure. But first we deal with a special case
4433 -- where we want to modify this check. If the body of the subprogram
4434 -- starts with a raise statement or its equivalent, or if the body
4435 -- consists entirely of a null statement, then it is pretty obvious that
4436 -- it is OK to not reference the parameters. For example, this might be
4437 -- the following common idiom for a stubbed function: statement of the
4438 -- procedure raises an exception. In particular this deals with the
4439 -- common idiom of a stubbed function, which appears something like:
4441 -- function F (A : Integer) return Some_Type;
4444 -- raise Program_Error;
4448 -- Here the purpose of X is simply to satisfy the annoying requirement
4449 -- in Ada that there be at least one return, and we certainly do not
4450 -- want to go posting warnings on X that it is not initialized. On
4451 -- the other hand, if X is entirely unreferenced that should still
4454 -- What we do is to detect these cases, and if we find them, flag the
4455 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4456 -- suppress unwanted warnings. For the case of the function stub above
4457 -- we have a special test to set X as apparently assigned to suppress
4464 -- Skip initial labels (for one thing this occurs when we are in
4465 -- front-end ZCX mode, but in any case it is irrelevant), and also
4466 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
4468 Stm := First (Statements (HSS));
4469 while Nkind (Stm) = N_Label
4470 or else Nkind (Stm) in N_Push_xxx_Label
4475 -- Do the test on the original statement before expansion
4478 Ostm : constant Node_Id := Original_Node (Stm);
4481 -- If explicit raise statement, turn on flag
4483 if Nkind (Ostm) = N_Raise_Statement then
4484 Set_Trivial_Subprogram (Stm);
4486 -- If null statement, and no following statements, turn on flag
4488 elsif Nkind (Stm) = N_Null_Statement
4489 and then Comes_From_Source (Stm)
4490 and then No (Next (Stm))
4492 Set_Trivial_Subprogram (Stm);
4494 -- Check for explicit call cases which likely raise an exception
4496 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4497 if Is_Entity_Name (Name (Ostm)) then
4499 Ent : constant Entity_Id := Entity (Name (Ostm));
4502 -- If the procedure is marked No_Return, then likely it
4503 -- raises an exception, but in any case it is not coming
4504 -- back here, so turn on the flag.
4507 and then Ekind (Ent) = E_Procedure
4508 and then No_Return (Ent)
4510 Set_Trivial_Subprogram (Stm);
4518 -- Check for variables that are never modified
4525 -- If there is a separate spec, then transfer Never_Set_In_Source
4526 -- flags from out parameters to the corresponding entities in the
4527 -- body. The reason we do that is we want to post error flags on
4528 -- the body entities, not the spec entities.
4530 if Present (Spec_Id) then
4531 E1 := First_Entity (Spec_Id);
4532 while Present (E1) loop
4533 if Ekind (E1) = E_Out_Parameter then
4534 E2 := First_Entity (Body_Id);
4535 while Present (E2) loop
4536 exit when Chars (E1) = Chars (E2);
4540 if Present (E2) then
4541 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4549 -- Check references in body
4551 Check_References (Body_Id);
4554 -- Check for nested subprogram, and mark outer level subprogram if so
4560 if Present (Spec_Id) then
4567 Ent := Enclosing_Subprogram (Ent);
4568 exit when No (Ent) or else Is_Subprogram (Ent);
4571 if Present (Ent) then
4572 Set_Has_Nested_Subprogram (Ent);
4576 -- Restore the limited views in the spec, if any, to let the back end
4577 -- process it without running into circularities.
4579 if Exch_Views /= No_Elist then
4580 Restore_Limited_Views (Exch_Views);
4583 if Mask_Types /= No_Elist then
4584 Unmask_Unfrozen_Types (Mask_Types);
4587 if Present (Desig_View) then
4588 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4592 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4593 Restore_Ghost_Mode (Saved_GM);
4594 end Analyze_Subprogram_Body_Helper;
4596 ------------------------------------
4597 -- Analyze_Subprogram_Declaration --
4598 ------------------------------------
4600 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4601 Scop : constant Entity_Id := Current_Scope;
4602 Designator : Entity_Id;
4604 Is_Completion : Boolean;
4605 -- Indicates whether a null procedure declaration is a completion
4608 -- Null procedures are not allowed in SPARK
4610 if Nkind (Specification (N)) = N_Procedure_Specification
4611 and then Null_Present (Specification (N))
4613 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4615 -- Null procedures are allowed in protected types, following the
4616 -- recent AI12-0147.
4618 if Is_Protected_Type (Current_Scope)
4619 and then Ada_Version < Ada_2012
4621 Error_Msg_N ("protected operation cannot be a null procedure", N);
4624 Analyze_Null_Procedure (N, Is_Completion);
4626 -- The null procedure acts as a body, nothing further is needed
4628 if Is_Completion then
4633 Designator := Analyze_Subprogram_Specification (Specification (N));
4635 -- A reference may already have been generated for the unit name, in
4636 -- which case the following call is redundant. However it is needed for
4637 -- declarations that are the rewriting of an expression function.
4639 Generate_Definition (Designator);
4641 -- Set the SPARK mode from the current context (may be overwritten later
4642 -- with explicit pragma). This is not done for entry barrier functions
4643 -- because they are generated outside the protected type and should not
4644 -- carry the mode of the enclosing context.
4646 if Nkind (N) = N_Subprogram_Declaration
4647 and then Is_Entry_Barrier_Function (N)
4651 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4652 Set_SPARK_Pragma_Inherited (Designator);
4655 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4656 -- the body of this subprogram is instantiated or inlined later and out
4657 -- of context. The body uses this attribute to restore the value of the
4660 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4661 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4664 if Debug_Flag_C then
4665 Write_Str ("==> subprogram spec ");
4666 Write_Name (Chars (Designator));
4667 Write_Str (" from ");
4668 Write_Location (Sloc (N));
4673 Validate_RCI_Subprogram_Declaration (N);
4674 New_Overloaded_Entity (Designator);
4675 Check_Delayed_Subprogram (Designator);
4677 -- If the type of the first formal of the current subprogram is a non-
4678 -- generic tagged private type, mark the subprogram as being a private
4679 -- primitive. Ditto if this is a function with controlling result, and
4680 -- the return type is currently private. In both cases, the type of the
4681 -- controlling argument or result must be in the current scope for the
4682 -- operation to be primitive.
4684 if Has_Controlling_Result (Designator)
4685 and then Is_Private_Type (Etype (Designator))
4686 and then Scope (Etype (Designator)) = Current_Scope
4687 and then not Is_Generic_Actual_Type (Etype (Designator))
4689 Set_Is_Private_Primitive (Designator);
4691 elsif Present (First_Formal (Designator)) then
4693 Formal_Typ : constant Entity_Id :=
4694 Etype (First_Formal (Designator));
4696 Set_Is_Private_Primitive (Designator,
4697 Is_Tagged_Type (Formal_Typ)
4698 and then Scope (Formal_Typ) = Current_Scope
4699 and then Is_Private_Type (Formal_Typ)
4700 and then not Is_Generic_Actual_Type (Formal_Typ));
4704 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4707 if Ada_Version >= Ada_2005
4708 and then Comes_From_Source (N)
4709 and then Is_Dispatching_Operation (Designator)
4716 if Has_Controlling_Result (Designator) then
4717 Etyp := Etype (Designator);
4720 E := First_Entity (Designator);
4722 and then Is_Formal (E)
4723 and then not Is_Controlling_Formal (E)
4731 if Is_Access_Type (Etyp) then
4732 Etyp := Directly_Designated_Type (Etyp);
4735 if Is_Interface (Etyp)
4736 and then not Is_Abstract_Subprogram (Designator)
4737 and then not (Ekind (Designator) = E_Procedure
4738 and then Null_Present (Specification (N)))
4740 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4742 -- Specialize error message based on procedures vs. functions,
4743 -- since functions can't be null subprograms.
4745 if Ekind (Designator) = E_Procedure then
4747 ("interface procedure % must be abstract or null", N);
4750 ("interface function % must be abstract", N);
4756 -- What is the following code for, it used to be
4758 -- ??? Set_Suppress_Elaboration_Checks
4759 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4761 -- The following seems equivalent, but a bit dubious
4763 if Elaboration_Checks_Suppressed (Designator) then
4764 Set_Kill_Elaboration_Checks (Designator);
4767 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4768 Set_Categorization_From_Scope (Designator, Scop);
4771 -- For a compilation unit, check for library-unit pragmas
4773 Push_Scope (Designator);
4774 Set_Categorization_From_Pragmas (N);
4775 Validate_Categorization_Dependency (N, Designator);
4779 -- For a compilation unit, set body required. This flag will only be
4780 -- reset if a valid Import or Interface pragma is processed later on.
4782 if Nkind (Parent (N)) = N_Compilation_Unit then
4783 Set_Body_Required (Parent (N), True);
4785 if Ada_Version >= Ada_2005
4786 and then Nkind (Specification (N)) = N_Procedure_Specification
4787 and then Null_Present (Specification (N))
4790 ("null procedure cannot be declared at library level", N);
4794 Generate_Reference_To_Formals (Designator);
4795 Check_Eliminated (Designator);
4797 if Debug_Flag_C then
4799 Write_Str ("<== subprogram spec ");
4800 Write_Name (Chars (Designator));
4801 Write_Str (" from ");
4802 Write_Location (Sloc (N));
4806 if Is_Protected_Type (Current_Scope) then
4808 -- Indicate that this is a protected operation, because it may be
4809 -- used in subsequent declarations within the protected type.
4811 Set_Convention (Designator, Convention_Protected);
4814 List_Inherited_Pre_Post_Aspects (Designator);
4816 if Has_Aspects (N) then
4817 Analyze_Aspect_Specifications (N, Designator);
4819 end Analyze_Subprogram_Declaration;
4821 --------------------------------------
4822 -- Analyze_Subprogram_Specification --
4823 --------------------------------------
4825 -- Reminder: N here really is a subprogram specification (not a subprogram
4826 -- declaration). This procedure is called to analyze the specification in
4827 -- both subprogram bodies and subprogram declarations (specs).
4829 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4830 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4831 -- Determine whether entity E denotes the spec or body of an invariant
4834 ------------------------------------
4835 -- Is_Invariant_Procedure_Or_Body --
4836 ------------------------------------
4838 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4839 Decl : constant Node_Id := Unit_Declaration_Node (E);
4843 if Nkind (Decl) = N_Subprogram_Body then
4844 Spec := Corresponding_Spec (Decl);
4851 and then Ekind (Spec) = E_Procedure
4852 and then (Is_Partial_Invariant_Procedure (Spec)
4853 or else Is_Invariant_Procedure (Spec));
4854 end Is_Invariant_Procedure_Or_Body;
4858 Designator : constant Entity_Id := Defining_Entity (N);
4859 Formals : constant List_Id := Parameter_Specifications (N);
4861 -- Start of processing for Analyze_Subprogram_Specification
4864 -- User-defined operator is not allowed in SPARK, except as a renaming
4866 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4867 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4869 Check_SPARK_05_Restriction
4870 ("user-defined operator is not allowed", N);
4873 -- Proceed with analysis. Do not emit a cross-reference entry if the
4874 -- specification comes from an expression function, because it may be
4875 -- the completion of a previous declaration. It is not, the cross-
4876 -- reference entry will be emitted for the new subprogram declaration.
4878 if Nkind (Parent (N)) /= N_Expression_Function then
4879 Generate_Definition (Designator);
4882 if Nkind (N) = N_Function_Specification then
4883 Set_Ekind (Designator, E_Function);
4884 Set_Mechanism (Designator, Default_Mechanism);
4886 Set_Ekind (Designator, E_Procedure);
4887 Set_Etype (Designator, Standard_Void_Type);
4890 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4891 -- those subprograms which could be inlined in GNATprove mode (because
4892 -- Body_To_Inline is non-Empty) but should not be inlined.
4894 if GNATprove_Mode then
4895 Set_Is_Inlined_Always (Designator);
4898 -- Introduce new scope for analysis of the formals and the return type
4900 Set_Scope (Designator, Current_Scope);
4902 if Present (Formals) then
4903 Push_Scope (Designator);
4904 Process_Formals (Formals, N);
4906 -- Check dimensions in N for formals with default expression
4908 Analyze_Dimension_Formals (N, Formals);
4910 -- Ada 2005 (AI-345): If this is an overriding operation of an
4911 -- inherited interface operation, and the controlling type is
4912 -- a synchronized type, replace the type with its corresponding
4913 -- record, to match the proper signature of an overriding operation.
4914 -- Same processing for an access parameter whose designated type is
4915 -- derived from a synchronized interface.
4917 -- This modification is not done for invariant procedures because
4918 -- the corresponding record may not necessarely be visible when the
4919 -- concurrent type acts as the full view of a private type.
4922 -- type Prot is private with Type_Invariant => ...;
4923 -- procedure ConcInvariant (Obj : Prot);
4925 -- protected type Prot is ...;
4926 -- type Concurrent_Record_Prot is record ...;
4927 -- procedure ConcInvariant (Obj : Prot) is
4929 -- end ConcInvariant;
4932 -- In the example above, both the spec and body of the invariant
4933 -- procedure must utilize the private type as the controlling type.
4935 if Ada_Version >= Ada_2005
4936 and then not Is_Invariant_Procedure_Or_Body (Designator)
4940 Formal_Typ : Entity_Id;
4941 Rec_Typ : Entity_Id;
4942 Desig_Typ : Entity_Id;
4945 Formal := First_Formal (Designator);
4946 while Present (Formal) loop
4947 Formal_Typ := Etype (Formal);
4949 if Is_Concurrent_Type (Formal_Typ)
4950 and then Present (Corresponding_Record_Type (Formal_Typ))
4952 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4954 if Present (Interfaces (Rec_Typ)) then
4955 Set_Etype (Formal, Rec_Typ);
4958 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4959 Desig_Typ := Designated_Type (Formal_Typ);
4961 if Is_Concurrent_Type (Desig_Typ)
4962 and then Present (Corresponding_Record_Type (Desig_Typ))
4964 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4966 if Present (Interfaces (Rec_Typ)) then
4967 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
4972 Next_Formal (Formal);
4979 -- The subprogram scope is pushed and popped around the processing of
4980 -- the return type for consistency with call above to Process_Formals
4981 -- (which itself can call Analyze_Return_Type), and to ensure that any
4982 -- itype created for the return type will be associated with the proper
4985 elsif Nkind (N) = N_Function_Specification then
4986 Push_Scope (Designator);
4987 Analyze_Return_Type (N);
4993 if Nkind (N) = N_Function_Specification then
4995 -- Deal with operator symbol case
4997 if Nkind (Designator) = N_Defining_Operator_Symbol then
4998 Valid_Operator_Definition (Designator);
5001 May_Need_Actuals (Designator);
5003 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5004 -- the subprogram is abstract also. This does not apply to renaming
5005 -- declarations, where abstractness is inherited, and to subprogram
5006 -- bodies generated for stream operations, which become renamings as
5009 -- In case of primitives associated with abstract interface types
5010 -- the check is applied later (see Analyze_Subprogram_Declaration).
5012 if not Nkind_In (Original_Node (Parent (N)),
5013 N_Abstract_Subprogram_Declaration,
5014 N_Formal_Abstract_Subprogram_Declaration,
5015 N_Subprogram_Renaming_Declaration)
5017 if Is_Abstract_Type (Etype (Designator))
5018 and then not Is_Interface (Etype (Designator))
5021 ("function that returns abstract type must be abstract", N);
5023 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5024 -- access result whose designated type is abstract.
5026 elsif Ada_Version >= Ada_2012
5027 and then Nkind (Result_Definition (N)) = N_Access_Definition
5029 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5030 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5033 ("function whose access result designates abstract type "
5034 & "must be abstract", N);
5040 end Analyze_Subprogram_Specification;
5042 -----------------------
5043 -- Check_Conformance --
5044 -----------------------
5046 procedure Check_Conformance
5047 (New_Id : Entity_Id;
5049 Ctype : Conformance_Type;
5051 Conforms : out Boolean;
5052 Err_Loc : Node_Id := Empty;
5053 Get_Inst : Boolean := False;
5054 Skip_Controlling_Formals : Boolean := False)
5056 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5057 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5058 -- If Errmsg is True, then processing continues to post an error message
5059 -- for conformance error on given node. Two messages are output. The
5060 -- first message points to the previous declaration with a general "no
5061 -- conformance" message. The second is the detailed reason, supplied as
5062 -- Msg. The parameter N provide information for a possible & insertion
5063 -- in the message, and also provides the location for posting the
5064 -- message in the absence of a specified Err_Loc location.
5066 function Conventions_Match
5068 Id2 : Entity_Id) return Boolean;
5069 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5072 -----------------------
5073 -- Conformance_Error --
5074 -----------------------
5076 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5083 if No (Err_Loc) then
5089 Error_Msg_Sloc := Sloc (Old_Id);
5092 when Type_Conformant =>
5093 Error_Msg_N -- CODEFIX
5094 ("not type conformant with declaration#!", Enode);
5096 when Mode_Conformant =>
5097 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5099 ("not mode conformant with operation inherited#!",
5103 ("not mode conformant with declaration#!", Enode);
5106 when Subtype_Conformant =>
5107 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5109 ("not subtype conformant with operation inherited#!",
5113 ("not subtype conformant with declaration#!", Enode);
5116 when Fully_Conformant =>
5117 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5118 Error_Msg_N -- CODEFIX
5119 ("not fully conformant with operation inherited#!",
5122 Error_Msg_N -- CODEFIX
5123 ("not fully conformant with declaration#!", Enode);
5127 Error_Msg_NE (Msg, Enode, N);
5129 end Conformance_Error;
5131 -----------------------
5132 -- Conventions_Match --
5133 -----------------------
5135 function Conventions_Match
5137 Id2 : Entity_Id) return Boolean
5140 -- Ignore the conventions of anonymous access-to-subprogram types
5141 -- and subprogram types because these are internally generated and
5142 -- the only way these may receive a convention is if they inherit
5143 -- the convention of a related subprogram.
5145 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5148 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5153 -- Otherwise compare the conventions directly
5156 return Convention (Id1) = Convention (Id2);
5158 end Conventions_Match;
5162 Old_Type : constant Entity_Id := Etype (Old_Id);
5163 New_Type : constant Entity_Id := Etype (New_Id);
5164 Old_Formal : Entity_Id;
5165 New_Formal : Entity_Id;
5166 Access_Types_Match : Boolean;
5167 Old_Formal_Base : Entity_Id;
5168 New_Formal_Base : Entity_Id;
5170 -- Start of processing for Check_Conformance
5175 -- We need a special case for operators, since they don't appear
5178 if Ctype = Type_Conformant then
5179 if Ekind (New_Id) = E_Operator
5180 and then Operator_Matches_Spec (New_Id, Old_Id)
5186 -- If both are functions/operators, check return types conform
5188 if Old_Type /= Standard_Void_Type
5190 New_Type /= Standard_Void_Type
5192 -- If we are checking interface conformance we omit controlling
5193 -- arguments and result, because we are only checking the conformance
5194 -- of the remaining parameters.
5196 if Has_Controlling_Result (Old_Id)
5197 and then Has_Controlling_Result (New_Id)
5198 and then Skip_Controlling_Formals
5202 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5203 if Ctype >= Subtype_Conformant
5204 and then not Predicates_Match (Old_Type, New_Type)
5207 ("\predicate of return type does not match!", New_Id);
5210 ("\return type does not match!", New_Id);
5216 -- Ada 2005 (AI-231): In case of anonymous access types check the
5217 -- null-exclusion and access-to-constant attributes match.
5219 if Ada_Version >= Ada_2005
5220 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5222 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5223 or else Is_Access_Constant (Etype (Old_Type)) /=
5224 Is_Access_Constant (Etype (New_Type)))
5226 Conformance_Error ("\return type does not match!", New_Id);
5230 -- If either is a function/operator and the other isn't, error
5232 elsif Old_Type /= Standard_Void_Type
5233 or else New_Type /= Standard_Void_Type
5235 Conformance_Error ("\functions can only match functions!", New_Id);
5239 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5240 -- If this is a renaming as body, refine error message to indicate that
5241 -- the conflict is with the original declaration. If the entity is not
5242 -- frozen, the conventions don't have to match, the one of the renamed
5243 -- entity is inherited.
5245 if Ctype >= Subtype_Conformant then
5246 if not Conventions_Match (Old_Id, New_Id) then
5247 if not Is_Frozen (New_Id) then
5250 elsif Present (Err_Loc)
5251 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5252 and then Present (Corresponding_Spec (Err_Loc))
5254 Error_Msg_Name_1 := Chars (New_Id);
5256 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5257 Conformance_Error ("\prior declaration for% has convention %!");
5260 Conformance_Error ("\calling conventions do not match!");
5265 elsif Is_Formal_Subprogram (Old_Id)
5266 or else Is_Formal_Subprogram (New_Id)
5268 Conformance_Error ("\formal subprograms not allowed!");
5273 -- Deal with parameters
5275 -- Note: we use the entity information, rather than going directly
5276 -- to the specification in the tree. This is not only simpler, but
5277 -- absolutely necessary for some cases of conformance tests between
5278 -- operators, where the declaration tree simply does not exist.
5280 Old_Formal := First_Formal (Old_Id);
5281 New_Formal := First_Formal (New_Id);
5282 while Present (Old_Formal) and then Present (New_Formal) loop
5283 if Is_Controlling_Formal (Old_Formal)
5284 and then Is_Controlling_Formal (New_Formal)
5285 and then Skip_Controlling_Formals
5287 -- The controlling formals will have different types when
5288 -- comparing an interface operation with its match, but both
5289 -- or neither must be access parameters.
5291 if Is_Access_Type (Etype (Old_Formal))
5293 Is_Access_Type (Etype (New_Formal))
5295 goto Skip_Controlling_Formal;
5298 ("\access parameter does not match!", New_Formal);
5302 -- Ada 2012: Mode conformance also requires that formal parameters
5303 -- be both aliased, or neither.
5305 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5306 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5308 ("\aliased parameter mismatch!", New_Formal);
5312 if Ctype = Fully_Conformant then
5314 -- Names must match. Error message is more accurate if we do
5315 -- this before checking that the types of the formals match.
5317 if Chars (Old_Formal) /= Chars (New_Formal) then
5318 Conformance_Error ("\name& does not match!", New_Formal);
5320 -- Set error posted flag on new formal as well to stop
5321 -- junk cascaded messages in some cases.
5323 Set_Error_Posted (New_Formal);
5327 -- Null exclusion must match
5329 if Null_Exclusion_Present (Parent (Old_Formal))
5331 Null_Exclusion_Present (Parent (New_Formal))
5333 -- Only give error if both come from source. This should be
5334 -- investigated some time, since it should not be needed ???
5336 if Comes_From_Source (Old_Formal)
5338 Comes_From_Source (New_Formal)
5341 ("\null exclusion for& does not match", New_Formal);
5343 -- Mark error posted on the new formal to avoid duplicated
5344 -- complaint about types not matching.
5346 Set_Error_Posted (New_Formal);
5351 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5352 -- case occurs whenever a subprogram is being renamed and one of its
5353 -- parameters imposes a null exclusion. For example:
5355 -- type T is null record;
5356 -- type Acc_T is access T;
5357 -- subtype Acc_T_Sub is Acc_T;
5359 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5360 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5363 Old_Formal_Base := Etype (Old_Formal);
5364 New_Formal_Base := Etype (New_Formal);
5367 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5368 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5371 Access_Types_Match := Ada_Version >= Ada_2005
5373 -- Ensure that this rule is only applied when New_Id is a
5374 -- renaming of Old_Id.
5376 and then Nkind (Parent (Parent (New_Id))) =
5377 N_Subprogram_Renaming_Declaration
5378 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5379 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5380 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5382 -- Now handle the allowed access-type case
5384 and then Is_Access_Type (Old_Formal_Base)
5385 and then Is_Access_Type (New_Formal_Base)
5387 -- The type kinds must match. The only exception occurs with
5388 -- multiple generics of the form:
5391 -- type F is private; type A is private;
5392 -- type F_Ptr is access F; type A_Ptr is access A;
5393 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5394 -- package F_Pack is ... package A_Pack is
5395 -- package F_Inst is
5396 -- new F_Pack (A, A_Ptr, A_P);
5398 -- When checking for conformance between the parameters of A_P
5399 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5400 -- because the compiler has transformed A_Ptr into a subtype of
5401 -- F_Ptr. We catch this case in the code below.
5403 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5405 (Is_Generic_Type (Old_Formal_Base)
5406 and then Is_Generic_Type (New_Formal_Base)
5407 and then Is_Internal (New_Formal_Base)
5408 and then Etype (Etype (New_Formal_Base)) =
5410 and then Directly_Designated_Type (Old_Formal_Base) =
5411 Directly_Designated_Type (New_Formal_Base)
5412 and then ((Is_Itype (Old_Formal_Base)
5413 and then Can_Never_Be_Null (Old_Formal_Base))
5415 (Is_Itype (New_Formal_Base)
5416 and then Can_Never_Be_Null (New_Formal_Base)));
5418 -- Types must always match. In the visible part of an instance,
5419 -- usual overloading rules for dispatching operations apply, and
5420 -- we check base types (not the actual subtypes).
5422 if In_Instance_Visible_Part
5423 and then Is_Dispatching_Operation (New_Id)
5425 if not Conforming_Types
5426 (T1 => Base_Type (Etype (Old_Formal)),
5427 T2 => Base_Type (Etype (New_Formal)),
5429 Get_Inst => Get_Inst)
5430 and then not Access_Types_Match
5432 Conformance_Error ("\type of & does not match!", New_Formal);
5436 elsif not Conforming_Types
5437 (T1 => Old_Formal_Base,
5438 T2 => New_Formal_Base,
5440 Get_Inst => Get_Inst)
5441 and then not Access_Types_Match
5443 -- Don't give error message if old type is Any_Type. This test
5444 -- avoids some cascaded errors, e.g. in case of a bad spec.
5446 if Errmsg and then Old_Formal_Base = Any_Type then
5449 if Ctype >= Subtype_Conformant
5451 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5454 ("\predicate of & does not match!", New_Formal);
5457 ("\type of & does not match!", New_Formal);
5459 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5461 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5469 -- For mode conformance, mode must match
5471 if Ctype >= Mode_Conformant then
5472 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5473 if not Ekind_In (New_Id, E_Function, E_Procedure)
5474 or else not Is_Primitive_Wrapper (New_Id)
5476 Conformance_Error ("\mode of & does not match!", New_Formal);
5480 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5482 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5484 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5487 ("\mode of & does not match!", New_Formal);
5494 -- Part of mode conformance for access types is having the same
5495 -- constant modifier.
5497 elsif Access_Types_Match
5498 and then Is_Access_Constant (Old_Formal_Base) /=
5499 Is_Access_Constant (New_Formal_Base)
5502 ("\constant modifier does not match!", New_Formal);
5507 if Ctype >= Subtype_Conformant then
5509 -- Ada 2005 (AI-231): In case of anonymous access types check
5510 -- the null-exclusion and access-to-constant attributes must
5511 -- match. For null exclusion, we test the types rather than the
5512 -- formals themselves, since the attribute is only set reliably
5513 -- on the formals in the Ada 95 case, and we exclude the case
5514 -- where Old_Formal is marked as controlling, to avoid errors
5515 -- when matching completing bodies with dispatching declarations
5516 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5518 if Ada_Version >= Ada_2005
5519 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5520 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5522 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5523 Can_Never_Be_Null (Etype (New_Formal))
5525 not Is_Controlling_Formal (Old_Formal))
5527 Is_Access_Constant (Etype (Old_Formal)) /=
5528 Is_Access_Constant (Etype (New_Formal)))
5530 -- Do not complain if error already posted on New_Formal. This
5531 -- avoids some redundant error messages.
5533 and then not Error_Posted (New_Formal)
5535 -- It is allowed to omit the null-exclusion in case of stream
5536 -- attribute subprograms. We recognize stream subprograms
5537 -- through their TSS-generated suffix.
5540 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5543 if TSS_Name /= TSS_Stream_Read
5544 and then TSS_Name /= TSS_Stream_Write
5545 and then TSS_Name /= TSS_Stream_Input
5546 and then TSS_Name /= TSS_Stream_Output
5548 -- Here we have a definite conformance error. It is worth
5549 -- special casing the error message for the case of a
5550 -- controlling formal (which excludes null).
5552 if Is_Controlling_Formal (New_Formal) then
5553 Error_Msg_Node_2 := Scope (New_Formal);
5555 ("\controlling formal & of & excludes null, "
5556 & "declaration must exclude null as well",
5559 -- Normal case (couldn't we give more detail here???)
5563 ("\type of & does not match!", New_Formal);
5572 -- Full conformance checks
5574 if Ctype = Fully_Conformant then
5576 -- We have checked already that names match
5578 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5580 -- Check default expressions for in parameters
5583 NewD : constant Boolean :=
5584 Present (Default_Value (New_Formal));
5585 OldD : constant Boolean :=
5586 Present (Default_Value (Old_Formal));
5588 if NewD or OldD then
5590 -- The old default value has been analyzed because the
5591 -- current full declaration will have frozen everything
5592 -- before. The new default value has not been analyzed,
5593 -- so analyze it now before we check for conformance.
5596 Push_Scope (New_Id);
5597 Preanalyze_Spec_Expression
5598 (Default_Value (New_Formal), Etype (New_Formal));
5602 if not (NewD and OldD)
5603 or else not Fully_Conformant_Expressions
5604 (Default_Value (Old_Formal),
5605 Default_Value (New_Formal))
5608 ("\default expression for & does not match!",
5617 -- A couple of special checks for Ada 83 mode. These checks are
5618 -- skipped if either entity is an operator in package Standard,
5619 -- or if either old or new instance is not from the source program.
5621 if Ada_Version = Ada_83
5622 and then Sloc (Old_Id) > Standard_Location
5623 and then Sloc (New_Id) > Standard_Location
5624 and then Comes_From_Source (Old_Id)
5625 and then Comes_From_Source (New_Id)
5628 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5629 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5632 -- Explicit IN must be present or absent in both cases. This
5633 -- test is required only in the full conformance case.
5635 if In_Present (Old_Param) /= In_Present (New_Param)
5636 and then Ctype = Fully_Conformant
5639 ("\(Ada 83) IN must appear in both declarations",
5644 -- Grouping (use of comma in param lists) must be the same
5645 -- This is where we catch a misconformance like:
5648 -- A : Integer; B : Integer
5650 -- which are represented identically in the tree except
5651 -- for the setting of the flags More_Ids and Prev_Ids.
5653 if More_Ids (Old_Param) /= More_Ids (New_Param)
5654 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5657 ("\grouping of & does not match!", New_Formal);
5663 -- This label is required when skipping controlling formals
5665 <<Skip_Controlling_Formal>>
5667 Next_Formal (Old_Formal);
5668 Next_Formal (New_Formal);
5671 if Present (Old_Formal) then
5672 Conformance_Error ("\too few parameters!");
5675 elsif Present (New_Formal) then
5676 Conformance_Error ("\too many parameters!", New_Formal);
5679 end Check_Conformance;
5681 -----------------------
5682 -- Check_Conventions --
5683 -----------------------
5685 procedure Check_Conventions (Typ : Entity_Id) is
5686 Ifaces_List : Elist_Id;
5688 procedure Check_Convention (Op : Entity_Id);
5689 -- Verify that the convention of inherited dispatching operation Op is
5690 -- consistent among all subprograms it overrides. In order to minimize
5691 -- the search, Search_From is utilized to designate a specific point in
5692 -- the list rather than iterating over the whole list once more.
5694 ----------------------
5695 -- Check_Convention --
5696 ----------------------
5698 procedure Check_Convention (Op : Entity_Id) is
5699 Op_Conv : constant Convention_Id := Convention (Op);
5700 Iface_Conv : Convention_Id;
5701 Iface_Elmt : Elmt_Id;
5702 Iface_Prim_Elmt : Elmt_Id;
5703 Iface_Prim : Entity_Id;
5706 Iface_Elmt := First_Elmt (Ifaces_List);
5707 while Present (Iface_Elmt) loop
5709 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5710 while Present (Iface_Prim_Elmt) loop
5711 Iface_Prim := Node (Iface_Prim_Elmt);
5712 Iface_Conv := Convention (Iface_Prim);
5714 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5715 and then Iface_Conv /= Op_Conv
5718 ("inconsistent conventions in primitive operations", Typ);
5720 Error_Msg_Name_1 := Chars (Op);
5721 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5722 Error_Msg_Sloc := Sloc (Op);
5724 if Comes_From_Source (Op) or else No (Alias (Op)) then
5725 if not Present (Overridden_Operation (Op)) then
5726 Error_Msg_N ("\\primitive % defined #", Typ);
5729 ("\\overriding operation % with "
5730 & "convention % defined #", Typ);
5733 else pragma Assert (Present (Alias (Op)));
5734 Error_Msg_Sloc := Sloc (Alias (Op));
5735 Error_Msg_N ("\\inherited operation % with "
5736 & "convention % defined #", Typ);
5739 Error_Msg_Name_1 := Chars (Op);
5740 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5741 Error_Msg_Sloc := Sloc (Iface_Prim);
5742 Error_Msg_N ("\\overridden operation % with "
5743 & "convention % defined #", Typ);
5745 -- Avoid cascading errors
5750 Next_Elmt (Iface_Prim_Elmt);
5753 Next_Elmt (Iface_Elmt);
5755 end Check_Convention;
5759 Prim_Op : Entity_Id;
5760 Prim_Op_Elmt : Elmt_Id;
5762 -- Start of processing for Check_Conventions
5765 if not Has_Interfaces (Typ) then
5769 Collect_Interfaces (Typ, Ifaces_List);
5771 -- The algorithm checks every overriding dispatching operation against
5772 -- all the corresponding overridden dispatching operations, detecting
5773 -- differences in conventions.
5775 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5776 while Present (Prim_Op_Elmt) loop
5777 Prim_Op := Node (Prim_Op_Elmt);
5779 -- A small optimization: skip the predefined dispatching operations
5780 -- since they always have the same convention.
5782 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5783 Check_Convention (Prim_Op);
5786 Next_Elmt (Prim_Op_Elmt);
5788 end Check_Conventions;
5790 ------------------------------
5791 -- Check_Delayed_Subprogram --
5792 ------------------------------
5794 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5797 procedure Possible_Freeze (T : Entity_Id);
5798 -- T is the type of either a formal parameter or of the return type.
5799 -- If T is not yet frozen and needs a delayed freeze, then the
5800 -- subprogram itself must be delayed.
5802 ---------------------
5803 -- Possible_Freeze --
5804 ---------------------
5806 procedure Possible_Freeze (T : Entity_Id) is
5808 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5809 Set_Has_Delayed_Freeze (Designator);
5811 elsif Is_Access_Type (T)
5812 and then Has_Delayed_Freeze (Designated_Type (T))
5813 and then not Is_Frozen (Designated_Type (T))
5815 Set_Has_Delayed_Freeze (Designator);
5818 end Possible_Freeze;
5820 -- Start of processing for Check_Delayed_Subprogram
5823 -- All subprograms, including abstract subprograms, may need a freeze
5824 -- node if some formal type or the return type needs one.
5826 Possible_Freeze (Etype (Designator));
5827 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5829 -- Need delayed freeze if any of the formal types themselves need
5830 -- a delayed freeze and are not yet frozen.
5832 F := First_Formal (Designator);
5833 while Present (F) loop
5834 Possible_Freeze (Etype (F));
5835 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5839 -- Mark functions that return by reference. Note that it cannot be
5840 -- done for delayed_freeze subprograms because the underlying
5841 -- returned type may not be known yet (for private types)
5843 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5845 Typ : constant Entity_Id := Etype (Designator);
5846 Utyp : constant Entity_Id := Underlying_Type (Typ);
5848 if Is_Limited_View (Typ) then
5849 Set_Returns_By_Ref (Designator);
5850 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5851 Set_Returns_By_Ref (Designator);
5855 end Check_Delayed_Subprogram;
5857 ------------------------------------
5858 -- Check_Discriminant_Conformance --
5859 ------------------------------------
5861 procedure Check_Discriminant_Conformance
5866 Old_Discr : Entity_Id := First_Discriminant (Prev);
5867 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5868 New_Discr_Id : Entity_Id;
5869 New_Discr_Type : Entity_Id;
5871 procedure Conformance_Error (Msg : String; N : Node_Id);
5872 -- Post error message for conformance error on given node. Two messages
5873 -- are output. The first points to the previous declaration with a
5874 -- general "no conformance" message. The second is the detailed reason,
5875 -- supplied as Msg. The parameter N provide information for a possible
5876 -- & insertion in the message.
5878 -----------------------
5879 -- Conformance_Error --
5880 -----------------------
5882 procedure Conformance_Error (Msg : String; N : Node_Id) is
5884 Error_Msg_Sloc := Sloc (Prev_Loc);
5885 Error_Msg_N -- CODEFIX
5886 ("not fully conformant with declaration#!", N);
5887 Error_Msg_NE (Msg, N, N);
5888 end Conformance_Error;
5890 -- Start of processing for Check_Discriminant_Conformance
5893 while Present (Old_Discr) and then Present (New_Discr) loop
5894 New_Discr_Id := Defining_Identifier (New_Discr);
5896 -- The subtype mark of the discriminant on the full type has not
5897 -- been analyzed so we do it here. For an access discriminant a new
5900 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5902 Access_Definition (N, Discriminant_Type (New_Discr));
5905 Analyze (Discriminant_Type (New_Discr));
5906 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5908 -- Ada 2005: if the discriminant definition carries a null
5909 -- exclusion, create an itype to check properly for consistency
5910 -- with partial declaration.
5912 if Is_Access_Type (New_Discr_Type)
5913 and then Null_Exclusion_Present (New_Discr)
5916 Create_Null_Excluding_Itype
5917 (T => New_Discr_Type,
5918 Related_Nod => New_Discr,
5919 Scope_Id => Current_Scope);
5923 if not Conforming_Types
5924 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5926 Conformance_Error ("type of & does not match!", New_Discr_Id);
5929 -- Treat the new discriminant as an occurrence of the old one,
5930 -- for navigation purposes, and fill in some semantic
5931 -- information, for completeness.
5933 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5934 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5935 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5940 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5941 Conformance_Error ("name & does not match!", New_Discr_Id);
5945 -- Default expressions must match
5948 NewD : constant Boolean :=
5949 Present (Expression (New_Discr));
5950 OldD : constant Boolean :=
5951 Present (Expression (Parent (Old_Discr)));
5954 if NewD or OldD then
5956 -- The old default value has been analyzed and expanded,
5957 -- because the current full declaration will have frozen
5958 -- everything before. The new default values have not been
5959 -- expanded, so expand now to check conformance.
5962 Preanalyze_Spec_Expression
5963 (Expression (New_Discr), New_Discr_Type);
5966 if not (NewD and OldD)
5967 or else not Fully_Conformant_Expressions
5968 (Expression (Parent (Old_Discr)),
5969 Expression (New_Discr))
5973 ("default expression for & does not match!",
5980 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
5982 if Ada_Version = Ada_83 then
5984 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
5987 -- Grouping (use of comma in param lists) must be the same
5988 -- This is where we catch a misconformance like:
5991 -- A : Integer; B : Integer
5993 -- which are represented identically in the tree except
5994 -- for the setting of the flags More_Ids and Prev_Ids.
5996 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
5997 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6000 ("grouping of & does not match!", New_Discr_Id);
6006 Next_Discriminant (Old_Discr);
6010 if Present (Old_Discr) then
6011 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6014 elsif Present (New_Discr) then
6016 ("too many discriminants!", Defining_Identifier (New_Discr));
6019 end Check_Discriminant_Conformance;
6021 ----------------------------
6022 -- Check_Fully_Conformant --
6023 ----------------------------
6025 procedure Check_Fully_Conformant
6026 (New_Id : Entity_Id;
6028 Err_Loc : Node_Id := Empty)
6031 pragma Warnings (Off, Result);
6034 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6035 end Check_Fully_Conformant;
6037 --------------------------
6038 -- Check_Limited_Return --
6039 --------------------------
6041 procedure Check_Limited_Return
6047 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6048 -- replaced by anonymous access results. This is an incompatibility with
6049 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6050 -- controllable with special switch. ???
6052 -- A limited interface that is not immutably limited is OK
6054 if Is_Limited_Interface (R_Type)
6056 not (Is_Task_Interface (R_Type)
6057 or else Is_Protected_Interface (R_Type)
6058 or else Is_Synchronized_Interface (R_Type))
6062 elsif Is_Limited_Type (R_Type)
6063 and then not Is_Interface (R_Type)
6064 and then Comes_From_Source (N)
6065 and then not In_Instance_Body
6066 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6068 -- Error in Ada 2005
6070 if Ada_Version >= Ada_2005
6071 and then not Debug_Flag_Dot_L
6072 and then not GNAT_Mode
6075 ("(Ada 2005) cannot copy object of a limited type "
6076 & "(RM-2005 6.5(5.5/2))", Expr);
6078 if Is_Limited_View (R_Type) then
6080 ("\return by reference not permitted in Ada 2005", Expr);
6083 -- Warn in Ada 95 mode, to give folks a heads up about this
6086 -- In GNAT mode, this is just a warning, to allow it to be evilly
6087 -- turned off. Otherwise it is a real error.
6089 -- In a generic context, simplify the warning because it makes no
6090 -- sense to discuss pass-by-reference or copy.
6092 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6093 if Inside_A_Generic then
6095 ("return of limited object not permitted in Ada 2005 "
6096 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6098 elsif Is_Limited_View (R_Type) then
6100 ("return by reference not permitted in Ada 2005 "
6101 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6104 ("cannot copy object of a limited type in Ada 2005 "
6105 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6108 -- Ada 95 mode, and compatibility warnings disabled
6111 pragma Assert (Ada_Version <= Ada_95);
6112 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6113 return; -- skip continuation messages below
6116 if not Inside_A_Generic then
6118 ("\consider switching to return of access type", Expr);
6119 Explain_Limited_Type (R_Type, Expr);
6122 end Check_Limited_Return;
6124 ---------------------------
6125 -- Check_Mode_Conformant --
6126 ---------------------------
6128 procedure Check_Mode_Conformant
6129 (New_Id : Entity_Id;
6131 Err_Loc : Node_Id := Empty;
6132 Get_Inst : Boolean := False)
6135 pragma Warnings (Off, Result);
6138 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6139 end Check_Mode_Conformant;
6141 --------------------------------
6142 -- Check_Overriding_Indicator --
6143 --------------------------------
6145 procedure Check_Overriding_Indicator
6147 Overridden_Subp : Entity_Id;
6148 Is_Primitive : Boolean)
6154 -- No overriding indicator for literals
6156 if Ekind (Subp) = E_Enumeration_Literal then
6159 elsif Ekind (Subp) = E_Entry then
6160 Decl := Parent (Subp);
6162 -- No point in analyzing a malformed operator
6164 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6165 and then Error_Posted (Subp)
6170 Decl := Unit_Declaration_Node (Subp);
6173 if Nkind_In (Decl, N_Subprogram_Body,
6174 N_Subprogram_Body_Stub,
6175 N_Subprogram_Declaration,
6176 N_Abstract_Subprogram_Declaration,
6177 N_Subprogram_Renaming_Declaration)
6179 Spec := Specification (Decl);
6181 elsif Nkind (Decl) = N_Entry_Declaration then
6188 -- The overriding operation is type conformant with the overridden one,
6189 -- but the names of the formals are not required to match. If the names
6190 -- appear permuted in the overriding operation, this is a possible
6191 -- source of confusion that is worth diagnosing. Controlling formals
6192 -- often carry names that reflect the type, and it is not worthwhile
6193 -- requiring that their names match.
6195 if Present (Overridden_Subp)
6196 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6203 Form1 := First_Formal (Subp);
6204 Form2 := First_Formal (Overridden_Subp);
6206 -- If the overriding operation is a synchronized operation, skip
6207 -- the first parameter of the overridden operation, which is
6208 -- implicit in the new one. If the operation is declared in the
6209 -- body it is not primitive and all formals must match.
6211 if Is_Concurrent_Type (Scope (Subp))
6212 and then Is_Tagged_Type (Scope (Subp))
6213 and then not Has_Completion (Scope (Subp))
6215 Form2 := Next_Formal (Form2);
6218 if Present (Form1) then
6219 Form1 := Next_Formal (Form1);
6220 Form2 := Next_Formal (Form2);
6223 while Present (Form1) loop
6224 if not Is_Controlling_Formal (Form1)
6225 and then Present (Next_Formal (Form2))
6226 and then Chars (Form1) = Chars (Next_Formal (Form2))
6228 Error_Msg_Node_2 := Alias (Overridden_Subp);
6229 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6231 ("& does not match corresponding formal of&#",
6236 Next_Formal (Form1);
6237 Next_Formal (Form2);
6242 -- If there is an overridden subprogram, then check that there is no
6243 -- "not overriding" indicator, and mark the subprogram as overriding.
6244 -- This is not done if the overridden subprogram is marked as hidden,
6245 -- which can occur for the case of inherited controlled operations
6246 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6247 -- subprogram is not itself hidden. (Note: This condition could probably
6248 -- be simplified, leaving out the testing for the specific controlled
6249 -- cases, but it seems safer and clearer this way, and echoes similar
6250 -- special-case tests of this kind in other places.)
6252 if Present (Overridden_Subp)
6253 and then (not Is_Hidden (Overridden_Subp)
6255 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6258 and then Present (Alias (Overridden_Subp))
6259 and then not Is_Hidden (Alias (Overridden_Subp))))
6261 if Must_Not_Override (Spec) then
6262 Error_Msg_Sloc := Sloc (Overridden_Subp);
6264 if Ekind (Subp) = E_Entry then
6266 ("entry & overrides inherited operation #", Spec, Subp);
6269 ("subprogram & overrides inherited operation #", Spec, Subp);
6272 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6273 -- as an extension of Root_Controlled, and thus has a useless Adjust
6274 -- operation. This operation should not be inherited by other limited
6275 -- controlled types. An explicit Adjust for them is not overriding.
6277 elsif Must_Override (Spec)
6278 and then Chars (Overridden_Subp) = Name_Adjust
6279 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6280 and then Present (Alias (Overridden_Subp))
6281 and then In_Predefined_Unit (Alias (Overridden_Subp))
6284 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6285 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6287 elsif Is_Subprogram (Subp) then
6288 if Is_Init_Proc (Subp) then
6291 elsif No (Overridden_Operation (Subp)) then
6293 -- For entities generated by Derive_Subprograms the overridden
6294 -- operation is the inherited primitive (which is available
6295 -- through the attribute alias)
6297 if (Is_Dispatching_Operation (Subp)
6298 or else Is_Dispatching_Operation (Overridden_Subp))
6299 and then not Comes_From_Source (Overridden_Subp)
6300 and then Find_Dispatching_Type (Overridden_Subp) =
6301 Find_Dispatching_Type (Subp)
6302 and then Present (Alias (Overridden_Subp))
6303 and then Comes_From_Source (Alias (Overridden_Subp))
6305 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6306 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6309 Set_Overridden_Operation (Subp, Overridden_Subp);
6310 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6315 -- If primitive flag is set or this is a protected operation, then
6316 -- the operation is overriding at the point of its declaration, so
6317 -- warn if necessary. Otherwise it may have been declared before the
6318 -- operation it overrides and no check is required.
6321 and then not Must_Override (Spec)
6322 and then (Is_Primitive
6323 or else Ekind (Scope (Subp)) = E_Protected_Type)
6325 Style.Missing_Overriding (Decl, Subp);
6328 -- If Subp is an operator, it may override a predefined operation, if
6329 -- it is defined in the same scope as the type to which it applies.
6330 -- In that case Overridden_Subp is empty because of our implicit
6331 -- representation for predefined operators. We have to check whether the
6332 -- signature of Subp matches that of a predefined operator. Note that
6333 -- first argument provides the name of the operator, and the second
6334 -- argument the signature that may match that of a standard operation.
6335 -- If the indicator is overriding, then the operator must match a
6336 -- predefined signature, because we know already that there is no
6337 -- explicit overridden operation.
6339 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6340 if Must_Not_Override (Spec) then
6342 -- If this is not a primitive or a protected subprogram, then
6343 -- "not overriding" is illegal.
6346 and then Ekind (Scope (Subp)) /= E_Protected_Type
6348 Error_Msg_N ("overriding indicator only allowed "
6349 & "if subprogram is primitive", Subp);
6351 elsif Can_Override_Operator (Subp) then
6353 ("subprogram& overrides predefined operator ", Spec, Subp);
6356 elsif Must_Override (Spec) then
6357 if No (Overridden_Operation (Subp))
6358 and then not Can_Override_Operator (Subp)
6360 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6363 elsif not Error_Posted (Subp)
6364 and then Style_Check
6365 and then Can_Override_Operator (Subp)
6366 and then not In_Predefined_Unit (Subp)
6368 -- If style checks are enabled, indicate that the indicator is
6369 -- missing. However, at the point of declaration, the type of
6370 -- which this is a primitive operation may be private, in which
6371 -- case the indicator would be premature.
6373 if Has_Private_Declaration (Etype (Subp))
6374 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6378 Style.Missing_Overriding (Decl, Subp);
6382 elsif Must_Override (Spec) then
6383 if Ekind (Subp) = E_Entry then
6384 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6386 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6389 -- If the operation is marked "not overriding" and it's not primitive
6390 -- then an error is issued, unless this is an operation of a task or
6391 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6392 -- has been specified have already been checked above.
6394 elsif Must_Not_Override (Spec)
6395 and then not Is_Primitive
6396 and then Ekind (Subp) /= E_Entry
6397 and then Ekind (Scope (Subp)) /= E_Protected_Type
6400 ("overriding indicator only allowed if subprogram is primitive",
6404 end Check_Overriding_Indicator;
6410 -- Note: this procedure needs to know far too much about how the expander
6411 -- messes with exceptions. The use of the flag Exception_Junk and the
6412 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6413 -- works, but is not very clean. It would be better if the expansion
6414 -- routines would leave Original_Node working nicely, and we could use
6415 -- Original_Node here to ignore all the peculiar expander messing ???
6417 procedure Check_Returns
6421 Proc : Entity_Id := Empty)
6425 procedure Check_Statement_Sequence (L : List_Id);
6426 -- Internal recursive procedure to check a list of statements for proper
6427 -- termination by a return statement (or a transfer of control or a
6428 -- compound statement that is itself internally properly terminated).
6430 ------------------------------
6431 -- Check_Statement_Sequence --
6432 ------------------------------
6434 procedure Check_Statement_Sequence (L : List_Id) is
6439 function Assert_False return Boolean;
6440 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6441 -- rewritten as a null statement when assertions are off. The assert
6442 -- is not active, but it is still enough to kill the warning.
6448 function Assert_False return Boolean is
6449 Orig : constant Node_Id := Original_Node (Last_Stm);
6452 if Nkind (Orig) = N_Pragma
6453 and then Pragma_Name (Orig) = Name_Assert
6454 and then not Error_Posted (Orig)
6457 Arg : constant Node_Id :=
6458 First (Pragma_Argument_Associations (Orig));
6459 Exp : constant Node_Id := Expression (Arg);
6461 return Nkind (Exp) = N_Identifier
6462 and then Chars (Exp) = Name_False;
6472 Raise_Exception_Call : Boolean;
6473 -- Set True if statement sequence terminated by Raise_Exception call
6474 -- or a Reraise_Occurrence call.
6476 -- Start of processing for Check_Statement_Sequence
6479 Raise_Exception_Call := False;
6481 -- Get last real statement
6483 Last_Stm := Last (L);
6485 -- Deal with digging out exception handler statement sequences that
6486 -- have been transformed by the local raise to goto optimization.
6487 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6488 -- optimization has occurred, we are looking at something like:
6491 -- original stmts in block
6495 -- goto L1; | omitted if No_Exception_Propagation
6500 -- goto L3; -- skip handler when exception not raised
6502 -- <<L1>> -- target label for local exception
6516 -- and what we have to do is to dig out the estmts1 and estmts2
6517 -- sequences (which were the original sequences of statements in
6518 -- the exception handlers) and check them.
6520 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6525 exit when Nkind (Stm) /= N_Block_Statement;
6526 exit when not Exception_Junk (Stm);
6529 exit when Nkind (Stm) /= N_Label;
6530 exit when not Exception_Junk (Stm);
6531 Check_Statement_Sequence
6532 (Statements (Handled_Statement_Sequence (Next (Stm))));
6537 exit when Nkind (Stm) /= N_Goto_Statement;
6538 exit when not Exception_Junk (Stm);
6542 -- Don't count pragmas
6544 while Nkind (Last_Stm) = N_Pragma
6546 -- Don't count call to SS_Release (can happen after Raise_Exception)
6549 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6551 Nkind (Name (Last_Stm)) = N_Identifier
6553 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6555 -- Don't count exception junk
6558 (Nkind_In (Last_Stm, N_Goto_Statement,
6560 N_Object_Declaration)
6561 and then Exception_Junk (Last_Stm))
6562 or else Nkind (Last_Stm) in N_Push_xxx_Label
6563 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6565 -- Inserted code, such as finalization calls, is irrelevant: we only
6566 -- need to check original source.
6568 or else Is_Rewrite_Insertion (Last_Stm)
6573 -- Here we have the "real" last statement
6575 Kind := Nkind (Last_Stm);
6577 -- Transfer of control, OK. Note that in the No_Return procedure
6578 -- case, we already diagnosed any explicit return statements, so
6579 -- we can treat them as OK in this context.
6581 if Is_Transfer (Last_Stm) then
6584 -- Check cases of explicit non-indirect procedure calls
6586 elsif Kind = N_Procedure_Call_Statement
6587 and then Is_Entity_Name (Name (Last_Stm))
6589 -- Check call to Raise_Exception procedure which is treated
6590 -- specially, as is a call to Reraise_Occurrence.
6592 -- We suppress the warning in these cases since it is likely that
6593 -- the programmer really does not expect to deal with the case
6594 -- of Null_Occurrence, and thus would find a warning about a
6595 -- missing return curious, and raising Program_Error does not
6596 -- seem such a bad behavior if this does occur.
6598 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6599 -- behavior will be to raise Constraint_Error (see AI-329).
6601 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6603 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6605 Raise_Exception_Call := True;
6607 -- For Raise_Exception call, test first argument, if it is
6608 -- an attribute reference for a 'Identity call, then we know
6609 -- that the call cannot possibly return.
6612 Arg : constant Node_Id :=
6613 Original_Node (First_Actual (Last_Stm));
6615 if Nkind (Arg) = N_Attribute_Reference
6616 and then Attribute_Name (Arg) = Name_Identity
6623 -- If statement, need to look inside if there is an else and check
6624 -- each constituent statement sequence for proper termination.
6626 elsif Kind = N_If_Statement
6627 and then Present (Else_Statements (Last_Stm))
6629 Check_Statement_Sequence (Then_Statements (Last_Stm));
6630 Check_Statement_Sequence (Else_Statements (Last_Stm));
6632 if Present (Elsif_Parts (Last_Stm)) then
6634 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6637 while Present (Elsif_Part) loop
6638 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6646 -- Case statement, check each case for proper termination
6648 elsif Kind = N_Case_Statement then
6652 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6653 while Present (Case_Alt) loop
6654 Check_Statement_Sequence (Statements (Case_Alt));
6655 Next_Non_Pragma (Case_Alt);
6661 -- Block statement, check its handled sequence of statements
6663 elsif Kind = N_Block_Statement then
6669 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6678 -- Loop statement. If there is an iteration scheme, we can definitely
6679 -- fall out of the loop. Similarly if there is an exit statement, we
6680 -- can fall out. In either case we need a following return.
6682 elsif Kind = N_Loop_Statement then
6683 if Present (Iteration_Scheme (Last_Stm))
6684 or else Has_Exit (Entity (Identifier (Last_Stm)))
6688 -- A loop with no exit statement or iteration scheme is either
6689 -- an infinite loop, or it has some other exit (raise/return).
6690 -- In either case, no warning is required.
6696 -- Timed entry call, check entry call and delay alternatives
6698 -- Note: in expanded code, the timed entry call has been converted
6699 -- to a set of expanded statements on which the check will work
6700 -- correctly in any case.
6702 elsif Kind = N_Timed_Entry_Call then
6704 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6705 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6708 -- If statement sequence of entry call alternative is missing,
6709 -- then we can definitely fall through, and we post the error
6710 -- message on the entry call alternative itself.
6712 if No (Statements (ECA)) then
6715 -- If statement sequence of delay alternative is missing, then
6716 -- we can definitely fall through, and we post the error
6717 -- message on the delay alternative itself.
6719 -- Note: if both ECA and DCA are missing the return, then we
6720 -- post only one message, should be enough to fix the bugs.
6721 -- If not we will get a message next time on the DCA when the
6724 elsif No (Statements (DCA)) then
6727 -- Else check both statement sequences
6730 Check_Statement_Sequence (Statements (ECA));
6731 Check_Statement_Sequence (Statements (DCA));
6736 -- Conditional entry call, check entry call and else part
6738 -- Note: in expanded code, the conditional entry call has been
6739 -- converted to a set of expanded statements on which the check
6740 -- will work correctly in any case.
6742 elsif Kind = N_Conditional_Entry_Call then
6744 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6747 -- If statement sequence of entry call alternative is missing,
6748 -- then we can definitely fall through, and we post the error
6749 -- message on the entry call alternative itself.
6751 if No (Statements (ECA)) then
6754 -- Else check statement sequence and else part
6757 Check_Statement_Sequence (Statements (ECA));
6758 Check_Statement_Sequence (Else_Statements (Last_Stm));
6764 -- If we fall through, issue appropriate message
6768 -- Kill warning if last statement is a raise exception call,
6769 -- or a pragma Assert (False). Note that with assertions enabled,
6770 -- such a pragma has been converted into a raise exception call
6771 -- already, so the Assert_False is for the assertions off case.
6773 if not Raise_Exception_Call and then not Assert_False then
6775 -- In GNATprove mode, it is an error to have a missing return
6777 Error_Msg_Warn := SPARK_Mode /= On;
6779 -- Issue error message or warning
6782 ("RETURN statement missing following this statement<<!",
6785 ("\Program_Error ]<<!", Last_Stm);
6788 -- Note: we set Err even though we have not issued a warning
6789 -- because we still have a case of a missing return. This is
6790 -- an extremely marginal case, probably will never be noticed
6791 -- but we might as well get it right.
6795 -- Otherwise we have the case of a procedure marked No_Return
6798 if not Raise_Exception_Call then
6799 if GNATprove_Mode then
6801 ("implied return after this statement would have raised "
6802 & "Program_Error", Last_Stm);
6804 -- In normal compilation mode, do not warn on a generated call
6805 -- (e.g. in the body of a renaming as completion).
6807 elsif Comes_From_Source (Last_Stm) then
6809 ("implied return after this statement will raise "
6810 & "Program_Error??", Last_Stm);
6813 Error_Msg_Warn := SPARK_Mode /= On;
6815 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6819 RE : constant Node_Id :=
6820 Make_Raise_Program_Error (Sloc (Last_Stm),
6821 Reason => PE_Implicit_Return);
6823 Insert_After (Last_Stm, RE);
6827 end Check_Statement_Sequence;
6829 -- Start of processing for Check_Returns
6833 Check_Statement_Sequence (Statements (HSS));
6835 if Present (Exception_Handlers (HSS)) then
6836 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6837 while Present (Handler) loop
6838 Check_Statement_Sequence (Statements (Handler));
6839 Next_Non_Pragma (Handler);
6844 ----------------------------
6845 -- Check_Subprogram_Order --
6846 ----------------------------
6848 procedure Check_Subprogram_Order (N : Node_Id) is
6850 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6851 -- This is used to check if S1 > S2 in the sense required by this test,
6852 -- for example nameab < namec, but name2 < name10.
6854 -----------------------------
6855 -- Subprogram_Name_Greater --
6856 -----------------------------
6858 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6863 -- Deal with special case where names are identical except for a
6864 -- numerical suffix. These are handled specially, taking the numeric
6865 -- ordering from the suffix into account.
6868 while S1 (L1) in '0' .. '9' loop
6873 while S2 (L2) in '0' .. '9' loop
6877 -- If non-numeric parts non-equal, do straight compare
6879 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6882 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6883 -- that a missing suffix is treated as numeric zero in this test.
6887 while L1 < S1'Last loop
6889 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6893 while L2 < S2'Last loop
6895 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6900 end Subprogram_Name_Greater;
6902 -- Start of processing for Check_Subprogram_Order
6905 -- Check body in alpha order if this is option
6908 and then Style_Check_Order_Subprograms
6909 and then Nkind (N) = N_Subprogram_Body
6910 and then Comes_From_Source (N)
6911 and then In_Extended_Main_Source_Unit (N)
6915 renames Scope_Stack.Table
6916 (Scope_Stack.Last).Last_Subprogram_Name;
6918 Body_Id : constant Entity_Id :=
6919 Defining_Entity (Specification (N));
6922 Get_Decoded_Name_String (Chars (Body_Id));
6925 if Subprogram_Name_Greater
6926 (LSN.all, Name_Buffer (1 .. Name_Len))
6928 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6934 LSN := new String'(Name_Buffer (1 .. Name_Len));
6937 end Check_Subprogram_Order;
6939 ------------------------------
6940 -- Check_Subtype_Conformant --
6941 ------------------------------
6943 procedure Check_Subtype_Conformant
6944 (New_Id : Entity_Id;
6946 Err_Loc : Node_Id := Empty;
6947 Skip_Controlling_Formals : Boolean := False;
6948 Get_Inst : Boolean := False)
6951 pragma Warnings (Off, Result);
6954 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6955 Skip_Controlling_Formals => Skip_Controlling_Formals,
6956 Get_Inst => Get_Inst);
6957 end Check_Subtype_Conformant;
6959 -----------------------------------
6960 -- Check_Synchronized_Overriding --
6961 -----------------------------------
6963 procedure Check_Synchronized_Overriding
6964 (Def_Id : Entity_Id;
6965 Overridden_Subp : out Entity_Id)
6967 Ifaces_List : Elist_Id;
6971 function Matches_Prefixed_View_Profile
6972 (Prim_Params : List_Id;
6973 Iface_Params : List_Id) return Boolean;
6974 -- Determine whether a subprogram's parameter profile Prim_Params
6975 -- matches that of a potentially overridden interface subprogram
6976 -- Iface_Params. Also determine if the type of first parameter of
6977 -- Iface_Params is an implemented interface.
6979 -----------------------------------
6980 -- Matches_Prefixed_View_Profile --
6981 -----------------------------------
6983 function Matches_Prefixed_View_Profile
6984 (Prim_Params : List_Id;
6985 Iface_Params : List_Id) return Boolean
6987 function Is_Implemented
6988 (Ifaces_List : Elist_Id;
6989 Iface : Entity_Id) return Boolean;
6990 -- Determine if Iface is implemented by the current task or
6993 --------------------
6994 -- Is_Implemented --
6995 --------------------
6997 function Is_Implemented
6998 (Ifaces_List : Elist_Id;
6999 Iface : Entity_Id) return Boolean
7001 Iface_Elmt : Elmt_Id;
7004 Iface_Elmt := First_Elmt (Ifaces_List);
7005 while Present (Iface_Elmt) loop
7006 if Node (Iface_Elmt) = Iface then
7010 Next_Elmt (Iface_Elmt);
7018 Iface_Id : Entity_Id;
7019 Iface_Param : Node_Id;
7020 Iface_Typ : Entity_Id;
7021 Prim_Id : Entity_Id;
7022 Prim_Param : Node_Id;
7023 Prim_Typ : Entity_Id;
7025 -- Start of processing for Matches_Prefixed_View_Profile
7028 Iface_Param := First (Iface_Params);
7029 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7031 if Is_Access_Type (Iface_Typ) then
7032 Iface_Typ := Designated_Type (Iface_Typ);
7035 Prim_Param := First (Prim_Params);
7037 -- The first parameter of the potentially overridden subprogram must
7038 -- be an interface implemented by Prim.
7040 if not Is_Interface (Iface_Typ)
7041 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7046 -- The checks on the object parameters are done, so move on to the
7047 -- rest of the parameters.
7049 if not In_Scope then
7050 Prim_Param := Next (Prim_Param);
7053 Iface_Param := Next (Iface_Param);
7054 while Present (Iface_Param) and then Present (Prim_Param) loop
7055 Iface_Id := Defining_Identifier (Iface_Param);
7056 Iface_Typ := Find_Parameter_Type (Iface_Param);
7058 Prim_Id := Defining_Identifier (Prim_Param);
7059 Prim_Typ := Find_Parameter_Type (Prim_Param);
7061 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7062 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7063 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7065 Iface_Typ := Designated_Type (Iface_Typ);
7066 Prim_Typ := Designated_Type (Prim_Typ);
7069 -- Case of multiple interface types inside a parameter profile
7071 -- (Obj_Param : in out Iface; ...; Param : Iface)
7073 -- If the interface type is implemented, then the matching type in
7074 -- the primitive should be the implementing record type.
7076 if Ekind (Iface_Typ) = E_Record_Type
7077 and then Is_Interface (Iface_Typ)
7078 and then Is_Implemented (Ifaces_List, Iface_Typ)
7080 if Prim_Typ /= Typ then
7084 -- The two parameters must be both mode and subtype conformant
7086 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7088 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7097 -- One of the two lists contains more parameters than the other
7099 if Present (Iface_Param) or else Present (Prim_Param) then
7104 end Matches_Prefixed_View_Profile;
7106 -- Start of processing for Check_Synchronized_Overriding
7109 Overridden_Subp := Empty;
7111 -- Def_Id must be an entry or a subprogram. We should skip predefined
7112 -- primitives internally generated by the front end; however at this
7113 -- stage predefined primitives are still not fully decorated. As a
7114 -- minor optimization we skip here internally generated subprograms.
7116 if (Ekind (Def_Id) /= E_Entry
7117 and then Ekind (Def_Id) /= E_Function
7118 and then Ekind (Def_Id) /= E_Procedure)
7119 or else not Comes_From_Source (Def_Id)
7124 -- Search for the concurrent declaration since it contains the list of
7125 -- all implemented interfaces. In this case, the subprogram is declared
7126 -- within the scope of a protected or a task type.
7128 if Present (Scope (Def_Id))
7129 and then Is_Concurrent_Type (Scope (Def_Id))
7130 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7132 Typ := Scope (Def_Id);
7135 -- The enclosing scope is not a synchronized type and the subprogram
7138 elsif No (First_Formal (Def_Id)) then
7141 -- The subprogram has formals and hence it may be a primitive of a
7145 Typ := Etype (First_Formal (Def_Id));
7147 if Is_Access_Type (Typ) then
7148 Typ := Directly_Designated_Type (Typ);
7151 if Is_Concurrent_Type (Typ)
7152 and then not Is_Generic_Actual_Type (Typ)
7156 -- This case occurs when the concurrent type is declared within a
7157 -- generic unit. As a result the corresponding record has been built
7158 -- and used as the type of the first formal, we just have to retrieve
7159 -- the corresponding concurrent type.
7161 elsif Is_Concurrent_Record_Type (Typ)
7162 and then not Is_Class_Wide_Type (Typ)
7163 and then Present (Corresponding_Concurrent_Type (Typ))
7165 Typ := Corresponding_Concurrent_Type (Typ);
7173 -- There is no overriding to check if this is an inherited operation in
7174 -- a type derivation for a generic actual.
7176 Collect_Interfaces (Typ, Ifaces_List);
7178 if Is_Empty_Elmt_List (Ifaces_List) then
7182 -- Determine whether entry or subprogram Def_Id overrides a primitive
7183 -- operation that belongs to one of the interfaces in Ifaces_List.
7186 Candidate : Entity_Id := Empty;
7187 Hom : Entity_Id := Empty;
7188 Subp : Entity_Id := Empty;
7191 -- Traverse the homonym chain, looking for a potentially overridden
7192 -- subprogram that belongs to an implemented interface.
7194 Hom := Current_Entity_In_Scope (Def_Id);
7195 while Present (Hom) loop
7199 or else not Is_Overloadable (Subp)
7200 or else not Is_Primitive (Subp)
7201 or else not Is_Dispatching_Operation (Subp)
7202 or else not Present (Find_Dispatching_Type (Subp))
7203 or else not Is_Interface (Find_Dispatching_Type (Subp))
7207 -- Entries and procedures can override abstract or null interface
7210 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7211 and then Ekind (Subp) = E_Procedure
7212 and then Matches_Prefixed_View_Profile
7213 (Parameter_Specifications (Parent (Def_Id)),
7214 Parameter_Specifications (Parent (Subp)))
7218 -- For an overridden subprogram Subp, check whether the mode
7219 -- of its first parameter is correct depending on the kind of
7220 -- synchronized type.
7223 Formal : constant Node_Id := First_Formal (Candidate);
7226 -- In order for an entry or a protected procedure to
7227 -- override, the first parameter of the overridden routine
7228 -- must be of mode "out", "in out", or access-to-variable.
7230 if Ekind_In (Candidate, E_Entry, E_Procedure)
7231 and then Is_Protected_Type (Typ)
7232 and then Ekind (Formal) /= E_In_Out_Parameter
7233 and then Ekind (Formal) /= E_Out_Parameter
7234 and then Nkind (Parameter_Type (Parent (Formal))) /=
7239 -- All other cases are OK since a task entry or routine does
7240 -- not have a restriction on the mode of the first parameter
7241 -- of the overridden interface routine.
7244 Overridden_Subp := Candidate;
7249 -- Functions can override abstract interface functions
7251 elsif Ekind (Def_Id) = E_Function
7252 and then Ekind (Subp) = E_Function
7253 and then Matches_Prefixed_View_Profile
7254 (Parameter_Specifications (Parent (Def_Id)),
7255 Parameter_Specifications (Parent (Subp)))
7256 and then Etype (Def_Id) = Etype (Subp)
7260 -- If an inherited subprogram is implemented by a protected
7261 -- function, then the first parameter of the inherited
7262 -- subprogram shall be of mode in, but not an access-to-
7263 -- variable parameter (RM 9.4(11/9)).
7265 if Present (First_Formal (Subp))
7266 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7268 (not Is_Access_Type (Etype (First_Formal (Subp)))
7270 Is_Access_Constant (Etype (First_Formal (Subp))))
7272 Overridden_Subp := Subp;
7277 Hom := Homonym (Hom);
7280 -- After examining all candidates for overriding, we are left with
7281 -- the best match, which is a mode-incompatible interface routine.
7283 if In_Scope and then Present (Candidate) then
7284 Error_Msg_PT (Def_Id, Candidate);
7287 Overridden_Subp := Candidate;
7290 end Check_Synchronized_Overriding;
7292 ---------------------------
7293 -- Check_Type_Conformant --
7294 ---------------------------
7296 procedure Check_Type_Conformant
7297 (New_Id : Entity_Id;
7299 Err_Loc : Node_Id := Empty)
7302 pragma Warnings (Off, Result);
7305 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7306 end Check_Type_Conformant;
7308 ---------------------------
7309 -- Can_Override_Operator --
7310 ---------------------------
7312 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7316 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7320 Typ := Base_Type (Etype (First_Formal (Subp)));
7322 -- Check explicitly that the operation is a primitive of the type
7324 return Operator_Matches_Spec (Subp, Subp)
7325 and then not Is_Generic_Type (Typ)
7326 and then Scope (Subp) = Scope (Typ)
7327 and then not Is_Class_Wide_Type (Typ);
7329 end Can_Override_Operator;
7331 ----------------------
7332 -- Conforming_Types --
7333 ----------------------
7335 function Conforming_Types
7338 Ctype : Conformance_Type;
7339 Get_Inst : Boolean := False) return Boolean
7341 function Base_Types_Match
7343 Typ_2 : Entity_Id) return Boolean;
7344 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7345 -- in different scopes (e.g. parent and child instances), then verify
7346 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7347 -- the same subtype chain. The whole purpose of this procedure is to
7348 -- prevent spurious ambiguities in an instantiation that may arise if
7349 -- two distinct generic types are instantiated with the same actual.
7351 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7352 -- An access parameter can designate an incomplete type. If the
7353 -- incomplete type is the limited view of a type from a limited_
7354 -- with_clause, check whether the non-limited view is available.
7355 -- If it is a (non-limited) incomplete type, get the full view.
7357 function Matches_Limited_With_View
7359 Typ_2 : Entity_Id) return Boolean;
7360 -- Returns True if and only if either Typ_1 denotes a limited view of
7361 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7362 -- the limited with view of a type is used in a subprogram declaration
7363 -- and the subprogram body is in the scope of a regular with clause for
7364 -- the same unit. In such a case, the two type entities are considered
7365 -- identical for purposes of conformance checking.
7367 ----------------------
7368 -- Base_Types_Match --
7369 ----------------------
7371 function Base_Types_Match
7373 Typ_2 : Entity_Id) return Boolean
7375 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7376 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7379 if Typ_1 = Typ_2 then
7382 elsif Base_1 = Base_2 then
7384 -- The following is too permissive. A more precise test should
7385 -- check that the generic actual is an ancestor subtype of the
7388 -- See code in Find_Corresponding_Spec that applies an additional
7389 -- filter to handle accidental amiguities in instances.
7392 not Is_Generic_Actual_Type (Typ_1)
7393 or else not Is_Generic_Actual_Type (Typ_2)
7394 or else Scope (Typ_1) /= Scope (Typ_2);
7396 -- If Typ_2 is a generic actual type it is declared as the subtype of
7397 -- the actual. If that actual is itself a subtype we need to use its
7398 -- own base type to check for compatibility.
7400 elsif Ekind (Base_2) = Ekind (Typ_2)
7401 and then Base_1 = Base_Type (Base_2)
7405 elsif Ekind (Base_1) = Ekind (Typ_1)
7406 and then Base_2 = Base_Type (Base_1)
7413 end Base_Types_Match;
7415 --------------------------
7416 -- Find_Designated_Type --
7417 --------------------------
7419 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7423 Desig := Directly_Designated_Type (Typ);
7425 if Ekind (Desig) = E_Incomplete_Type then
7427 -- If regular incomplete type, get full view if available
7429 if Present (Full_View (Desig)) then
7430 Desig := Full_View (Desig);
7432 -- If limited view of a type, get non-limited view if available,
7433 -- and check again for a regular incomplete type.
7435 elsif Present (Non_Limited_View (Desig)) then
7436 Desig := Get_Full_View (Non_Limited_View (Desig));
7441 end Find_Designated_Type;
7443 -------------------------------
7444 -- Matches_Limited_With_View --
7445 -------------------------------
7447 function Matches_Limited_With_View
7449 Typ_2 : Entity_Id) return Boolean
7451 function Is_Matching_Limited_View
7453 View : Entity_Id) return Boolean;
7454 -- Determine whether non-limited view View denotes type Typ in some
7455 -- conformant fashion.
7457 ------------------------------
7458 -- Is_Matching_Limited_View --
7459 ------------------------------
7461 function Is_Matching_Limited_View
7463 View : Entity_Id) return Boolean
7465 Root_Typ : Entity_Id;
7466 Root_View : Entity_Id;
7469 -- The non-limited view directly denotes the type
7474 -- The type is a subtype of the non-limited view
7476 elsif Is_Subtype_Of (Typ, View) then
7479 -- Both the non-limited view and the type denote class-wide types
7481 elsif Is_Class_Wide_Type (Typ)
7482 and then Is_Class_Wide_Type (View)
7484 Root_Typ := Root_Type (Typ);
7485 Root_View := Root_Type (View);
7487 if Root_Typ = Root_View then
7490 -- An incomplete tagged type and its full view may receive two
7491 -- distinct class-wide types when the related package has not
7492 -- been analyzed yet.
7495 -- type T is tagged; -- CW_1
7496 -- type T is tagged null record; -- CW_2
7499 -- This is because the package lacks any semantic information
7500 -- that may eventually link both views of T. As a consequence,
7501 -- a client of the limited view of Pack will see CW_2 while a
7502 -- client of the non-limited view of Pack will see CW_1.
7504 elsif Is_Incomplete_Type (Root_Typ)
7505 and then Present (Full_View (Root_Typ))
7506 and then Full_View (Root_Typ) = Root_View
7510 elsif Is_Incomplete_Type (Root_View)
7511 and then Present (Full_View (Root_View))
7512 and then Full_View (Root_View) = Root_Typ
7519 end Is_Matching_Limited_View;
7521 -- Start of processing for Matches_Limited_With_View
7524 -- In some cases a type imported through a limited_with clause, and
7525 -- its non-limited view are both visible, for example in an anonymous
7526 -- access-to-class-wide type in a formal, or when building the body
7527 -- for a subprogram renaming after the subprogram has been frozen.
7528 -- In these cases both entities designate the same type. In addition,
7529 -- if one of them is an actual in an instance, it may be a subtype of
7530 -- the non-limited view of the other.
7532 if From_Limited_With (Typ_1)
7533 and then From_Limited_With (Typ_2)
7534 and then Available_View (Typ_1) = Available_View (Typ_2)
7538 elsif From_Limited_With (Typ_1) then
7539 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7541 elsif From_Limited_With (Typ_2) then
7542 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7547 end Matches_Limited_With_View;
7551 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7553 Type_1 : Entity_Id := T1;
7554 Type_2 : Entity_Id := T2;
7556 -- Start of processing for Conforming_Types
7559 -- The context is an instance association for a formal access-to-
7560 -- subprogram type; the formal parameter types require mapping because
7561 -- they may denote other formal parameters of the generic unit.
7564 Type_1 := Get_Instance_Of (T1);
7565 Type_2 := Get_Instance_Of (T2);
7568 -- If one of the types is a view of the other introduced by a limited
7569 -- with clause, treat these as conforming for all purposes.
7571 if Matches_Limited_With_View (T1, T2) then
7574 elsif Base_Types_Match (Type_1, Type_2) then
7575 if Ctype <= Mode_Conformant then
7580 Subtypes_Statically_Match (Type_1, Type_2)
7581 and then Dimensions_Match (Type_1, Type_2);
7584 elsif Is_Incomplete_Or_Private_Type (Type_1)
7585 and then Present (Full_View (Type_1))
7586 and then Base_Types_Match (Full_View (Type_1), Type_2)
7589 Ctype <= Mode_Conformant
7590 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7592 elsif Ekind (Type_2) = E_Incomplete_Type
7593 and then Present (Full_View (Type_2))
7594 and then Base_Types_Match (Type_1, Full_View (Type_2))
7597 Ctype <= Mode_Conformant
7598 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7600 elsif Is_Private_Type (Type_2)
7601 and then In_Instance
7602 and then Present (Full_View (Type_2))
7603 and then Base_Types_Match (Type_1, Full_View (Type_2))
7606 Ctype <= Mode_Conformant
7607 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7609 -- Another confusion between views in a nested instance with an
7610 -- actual private type whose full view is not in scope.
7612 elsif Ekind (Type_2) = E_Private_Subtype
7613 and then In_Instance
7614 and then Etype (Type_2) = Type_1
7618 -- In Ada 2012, incomplete types (including limited views) can appear
7619 -- as actuals in instantiations.
7621 elsif Is_Incomplete_Type (Type_1)
7622 and then Is_Incomplete_Type (Type_2)
7623 and then (Used_As_Generic_Actual (Type_1)
7624 or else Used_As_Generic_Actual (Type_2))
7629 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7630 -- treated recursively because they carry a signature. As far as
7631 -- conformance is concerned, convention plays no role, and either
7632 -- or both could be access to protected subprograms.
7634 Are_Anonymous_Access_To_Subprogram_Types :=
7635 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7636 E_Anonymous_Access_Protected_Subprogram_Type)
7638 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7639 E_Anonymous_Access_Protected_Subprogram_Type);
7641 -- Test anonymous access type case. For this case, static subtype
7642 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7643 -- the base types because we may have built internal subtype entities
7644 -- to handle null-excluding types (see Process_Formals).
7646 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7648 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7650 -- Ada 2005 (AI-254)
7652 or else Are_Anonymous_Access_To_Subprogram_Types
7655 Desig_1 : Entity_Id;
7656 Desig_2 : Entity_Id;
7659 -- In Ada 2005, access constant indicators must match for
7660 -- subtype conformance.
7662 if Ada_Version >= Ada_2005
7663 and then Ctype >= Subtype_Conformant
7665 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7670 Desig_1 := Find_Designated_Type (Type_1);
7671 Desig_2 := Find_Designated_Type (Type_2);
7673 -- If the context is an instance association for a formal
7674 -- access-to-subprogram type; formal access parameter designated
7675 -- types require mapping because they may denote other formal
7676 -- parameters of the generic unit.
7679 Desig_1 := Get_Instance_Of (Desig_1);
7680 Desig_2 := Get_Instance_Of (Desig_2);
7683 -- It is possible for a Class_Wide_Type to be introduced for an
7684 -- incomplete type, in which case there is a separate class_ wide
7685 -- type for the full view. The types conform if their Etypes
7686 -- conform, i.e. one may be the full view of the other. This can
7687 -- only happen in the context of an access parameter, other uses
7688 -- of an incomplete Class_Wide_Type are illegal.
7690 if Is_Class_Wide_Type (Desig_1)
7692 Is_Class_Wide_Type (Desig_2)
7696 (Etype (Base_Type (Desig_1)),
7697 Etype (Base_Type (Desig_2)), Ctype);
7699 elsif Are_Anonymous_Access_To_Subprogram_Types then
7700 if Ada_Version < Ada_2005 then
7702 Ctype = Type_Conformant
7703 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7705 -- We must check the conformance of the signatures themselves
7709 Conformant : Boolean;
7712 (Desig_1, Desig_2, Ctype, False, Conformant);
7717 -- A limited view of an actual matches the corresponding
7718 -- incomplete formal.
7720 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7721 and then From_Limited_With (Desig_2)
7722 and then Used_As_Generic_Actual (Etype (Desig_2))
7727 return Base_Type (Desig_1) = Base_Type (Desig_2)
7728 and then (Ctype = Type_Conformant
7730 Subtypes_Statically_Match (Desig_1, Desig_2));
7734 -- Otherwise definitely no match
7737 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7738 and then Is_Access_Type (Type_2))
7739 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7740 and then Is_Access_Type (Type_1)))
7743 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7745 May_Hide_Profile := True;
7750 end Conforming_Types;
7752 --------------------------
7753 -- Create_Extra_Formals --
7754 --------------------------
7756 procedure Create_Extra_Formals (E : Entity_Id) is
7757 First_Extra : Entity_Id := Empty;
7759 Last_Extra : Entity_Id := Empty;
7761 function Add_Extra_Formal
7762 (Assoc_Entity : Entity_Id;
7765 Suffix : String) return Entity_Id;
7766 -- Add an extra formal to the current list of formals and extra formals.
7767 -- The extra formal is added to the end of the list of extra formals,
7768 -- and also returned as the result. These formals are always of mode IN.
7769 -- The new formal has the type Typ, is declared in Scope, and its name
7770 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7771 -- The following suffixes are currently used. They should not be changed
7772 -- without coordinating with CodePeer, which makes use of these to
7773 -- provide better messages.
7775 -- O denotes the Constrained bit.
7776 -- L denotes the accessibility level.
7777 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7778 -- the full list in exp_ch6.BIP_Formal_Kind.
7780 ----------------------
7781 -- Add_Extra_Formal --
7782 ----------------------
7784 function Add_Extra_Formal
7785 (Assoc_Entity : Entity_Id;
7788 Suffix : String) return Entity_Id
7790 EF : constant Entity_Id :=
7791 Make_Defining_Identifier (Sloc (Assoc_Entity),
7792 Chars => New_External_Name (Chars (Assoc_Entity),
7796 -- A little optimization. Never generate an extra formal for the
7797 -- _init operand of an initialization procedure, since it could
7800 if Chars (Formal) = Name_uInit then
7804 Set_Ekind (EF, E_In_Parameter);
7805 Set_Actual_Subtype (EF, Typ);
7806 Set_Etype (EF, Typ);
7807 Set_Scope (EF, Scope);
7808 Set_Mechanism (EF, Default_Mechanism);
7809 Set_Formal_Validity (EF);
7811 if No (First_Extra) then
7813 Set_Extra_Formals (Scope, First_Extra);
7816 if Present (Last_Extra) then
7817 Set_Extra_Formal (Last_Extra, EF);
7823 end Add_Extra_Formal;
7827 Formal_Type : Entity_Id;
7828 P_Formal : Entity_Id := Empty;
7830 -- Start of processing for Create_Extra_Formals
7833 -- We never generate extra formals if expansion is not active because we
7834 -- don't need them unless we are generating code.
7836 if not Expander_Active then
7840 -- No need to generate extra formals in interface thunks whose target
7841 -- primitive has no extra formals.
7843 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7847 -- If this is a derived subprogram then the subtypes of the parent
7848 -- subprogram's formal parameters will be used to determine the need
7849 -- for extra formals.
7851 if Is_Overloadable (E) and then Present (Alias (E)) then
7852 P_Formal := First_Formal (Alias (E));
7855 Formal := First_Formal (E);
7856 while Present (Formal) loop
7857 Last_Extra := Formal;
7858 Next_Formal (Formal);
7861 -- If Extra_Formals were already created, don't do it again. This
7862 -- situation may arise for subprogram types created as part of
7863 -- dispatching calls (see Expand_Dispatching_Call)
7865 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7869 -- If the subprogram is a predefined dispatching subprogram then don't
7870 -- generate any extra constrained or accessibility level formals. In
7871 -- general we suppress these for internal subprograms (by not calling
7872 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7873 -- generated stream attributes do get passed through because extra
7874 -- build-in-place formals are needed in some cases (limited 'Input).
7876 if Is_Predefined_Internal_Operation (E) then
7877 goto Test_For_Func_Result_Extras;
7880 Formal := First_Formal (E);
7881 while Present (Formal) loop
7883 -- Create extra formal for supporting the attribute 'Constrained.
7884 -- The case of a private type view without discriminants also
7885 -- requires the extra formal if the underlying type has defaulted
7888 if Ekind (Formal) /= E_In_Parameter then
7889 if Present (P_Formal) then
7890 Formal_Type := Etype (P_Formal);
7892 Formal_Type := Etype (Formal);
7895 -- Do not produce extra formals for Unchecked_Union parameters.
7896 -- Jump directly to the end of the loop.
7898 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7899 goto Skip_Extra_Formal_Generation;
7902 if not Has_Discriminants (Formal_Type)
7903 and then Ekind (Formal_Type) in Private_Kind
7904 and then Present (Underlying_Type (Formal_Type))
7906 Formal_Type := Underlying_Type (Formal_Type);
7909 -- Suppress the extra formal if formal's subtype is constrained or
7910 -- indefinite, or we're compiling for Ada 2012 and the underlying
7911 -- type is tagged and limited. In Ada 2012, a limited tagged type
7912 -- can have defaulted discriminants, but 'Constrained is required
7913 -- to return True, so the formal is never needed (see AI05-0214).
7914 -- Note that this ensures consistency of calling sequences for
7915 -- dispatching operations when some types in a class have defaults
7916 -- on discriminants and others do not (and requiring the extra
7917 -- formal would introduce distributed overhead).
7919 -- If the type does not have a completion yet, treat as prior to
7920 -- Ada 2012 for consistency.
7922 if Has_Discriminants (Formal_Type)
7923 and then not Is_Constrained (Formal_Type)
7924 and then Is_Definite_Subtype (Formal_Type)
7925 and then (Ada_Version < Ada_2012
7926 or else No (Underlying_Type (Formal_Type))
7928 (Is_Limited_Type (Formal_Type)
7931 (Underlying_Type (Formal_Type)))))
7933 Set_Extra_Constrained
7934 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7938 -- Create extra formal for supporting accessibility checking. This
7939 -- is done for both anonymous access formals and formals of named
7940 -- access types that are marked as controlling formals. The latter
7941 -- case can occur when Expand_Dispatching_Call creates a subprogram
7942 -- type and substitutes the types of access-to-class-wide actuals
7943 -- for the anonymous access-to-specific-type of controlling formals.
7944 -- Base_Type is applied because in cases where there is a null
7945 -- exclusion the formal may have an access subtype.
7947 -- This is suppressed if we specifically suppress accessibility
7948 -- checks at the package level for either the subprogram, or the
7949 -- package in which it resides. However, we do not suppress it
7950 -- simply if the scope has accessibility checks suppressed, since
7951 -- this could cause trouble when clients are compiled with a
7952 -- different suppression setting. The explicit checks at the
7953 -- package level are safe from this point of view.
7955 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7956 or else (Is_Controlling_Formal (Formal)
7957 and then Is_Access_Type (Base_Type (Etype (Formal)))))
7959 (Explicit_Suppress (E, Accessibility_Check)
7961 Explicit_Suppress (Scope (E), Accessibility_Check))
7964 or else Present (Extra_Accessibility (P_Formal)))
7966 Set_Extra_Accessibility
7967 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
7970 -- This label is required when skipping extra formal generation for
7971 -- Unchecked_Union parameters.
7973 <<Skip_Extra_Formal_Generation>>
7975 if Present (P_Formal) then
7976 Next_Formal (P_Formal);
7979 Next_Formal (Formal);
7982 <<Test_For_Func_Result_Extras>>
7984 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
7985 -- function call is ... determined by the point of call ...".
7987 if Needs_Result_Accessibility_Level (E) then
7988 Set_Extra_Accessibility_Of_Result
7989 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
7992 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
7993 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
7995 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
7997 Result_Subt : constant Entity_Id := Etype (E);
7998 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
7999 Formal_Typ : Entity_Id;
8000 Subp_Decl : Node_Id;
8002 Discard : Entity_Id;
8003 pragma Warnings (Off, Discard);
8006 -- In the case of functions with unconstrained result subtypes,
8007 -- add a 4-state formal indicating whether the return object is
8008 -- allocated by the caller (1), or should be allocated by the
8009 -- callee on the secondary stack (2), in the global heap (3), or
8010 -- in a user-defined storage pool (4). For the moment we just use
8011 -- Natural for the type of this formal. Note that this formal
8012 -- isn't usually needed in the case where the result subtype is
8013 -- constrained, but it is needed when the function has a tagged
8014 -- result, because generally such functions can be called in a
8015 -- dispatching context and such calls must be handled like calls
8016 -- to a class-wide function.
8018 if Needs_BIP_Alloc_Form (E) then
8021 (E, Standard_Natural,
8022 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8024 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8025 -- use a user-defined pool. This formal is not added on
8026 -- ZFP as those targets do not support pools.
8028 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8031 (E, RTE (RE_Root_Storage_Pool_Ptr),
8032 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8036 -- In the case of functions whose result type needs finalization,
8037 -- add an extra formal which represents the finalization master.
8039 if Needs_BIP_Finalization_Master (E) then
8042 (E, RTE (RE_Finalization_Master_Ptr),
8043 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8046 -- When the result type contains tasks, add two extra formals: the
8047 -- master of the tasks to be created, and the caller's activation
8050 if Has_Task (Full_Subt) then
8053 (E, RTE (RE_Master_Id),
8054 E, BIP_Formal_Suffix (BIP_Task_Master));
8057 (E, RTE (RE_Activation_Chain_Access),
8058 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8061 -- All build-in-place functions get an extra formal that will be
8062 -- passed the address of the return object within the caller.
8065 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8067 Set_Directly_Designated_Type (Formal_Typ, Result_Subt);
8068 Set_Etype (Formal_Typ, Formal_Typ);
8069 Set_Depends_On_Private
8070 (Formal_Typ, Has_Private_Component (Formal_Typ));
8071 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8072 Set_Is_Access_Constant (Formal_Typ, False);
8074 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8075 -- the designated type comes from the limited view (for back-end
8078 Set_From_Limited_With
8079 (Formal_Typ, From_Limited_With (Result_Subt));
8081 Layout_Type (Formal_Typ);
8083 -- Force the definition of the Itype in case of internal function
8084 -- calls within the same or nested scope.
8086 if Is_Subprogram_Or_Generic_Subprogram (E) then
8087 Subp_Decl := Parent (E);
8089 -- The insertion point for an Itype reference should be after
8090 -- the unit declaration node of the subprogram. An exception
8091 -- to this are inherited operations from a parent type in which
8092 -- case the derived type acts as their parent.
8094 if Nkind_In (Subp_Decl, N_Function_Specification,
8095 N_Procedure_Specification)
8097 Subp_Decl := Parent (Subp_Decl);
8100 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8105 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8108 end Create_Extra_Formals;
8110 -----------------------------
8111 -- Enter_Overloaded_Entity --
8112 -----------------------------
8114 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8115 function Matches_Predefined_Op return Boolean;
8116 -- This returns an approximation of whether S matches a predefined
8117 -- operator, based on the operator symbol, and the parameter and result
8118 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8120 ---------------------------
8121 -- Matches_Predefined_Op --
8122 ---------------------------
8124 function Matches_Predefined_Op return Boolean is
8125 Formal_1 : constant Entity_Id := First_Formal (S);
8126 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8127 Op : constant Name_Id := Chars (S);
8128 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8129 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8134 if Present (Formal_2) then
8136 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8139 -- All but "&" and "**" have same-types parameters
8148 if Type_1 /= Type_2 then
8153 -- Check parameter and result types
8161 Is_Boolean_Type (Result_Type)
8162 and then Result_Type = Type_1;
8168 Is_Integer_Type (Result_Type)
8169 and then Result_Type = Type_1;
8177 Is_Numeric_Type (Result_Type)
8178 and then Result_Type = Type_1;
8184 Is_Boolean_Type (Result_Type)
8185 and then not Is_Limited_Type (Type_1);
8193 Is_Boolean_Type (Result_Type)
8194 and then (Is_Array_Type (Type_1)
8195 or else Is_Scalar_Type (Type_1));
8197 when Name_Op_Concat =>
8198 return Is_Array_Type (Result_Type);
8200 when Name_Op_Expon =>
8202 (Is_Integer_Type (Result_Type)
8203 or else Is_Floating_Point_Type (Result_Type))
8204 and then Result_Type = Type_1
8205 and then Type_2 = Standard_Integer;
8208 raise Program_Error;
8221 Is_Numeric_Type (Result_Type)
8222 and then Result_Type = Type_1;
8226 Is_Boolean_Type (Result_Type)
8227 and then Result_Type = Type_1;
8230 raise Program_Error;
8233 end Matches_Predefined_Op;
8237 E : Entity_Id := Current_Entity_In_Scope (S);
8238 C_E : Entity_Id := Current_Entity (S);
8240 -- Start of processing for Enter_Overloaded_Entity
8244 Set_Has_Homonym (E);
8245 Set_Has_Homonym (S);
8248 Set_Is_Immediately_Visible (S);
8249 Set_Scope (S, Current_Scope);
8251 -- Chain new entity if front of homonym in current scope, so that
8252 -- homonyms are contiguous.
8254 if Present (E) and then E /= C_E then
8255 while Homonym (C_E) /= E loop
8256 C_E := Homonym (C_E);
8259 Set_Homonym (C_E, S);
8263 Set_Current_Entity (S);
8268 if Is_Inherited_Operation (S) then
8269 Append_Inherited_Subprogram (S);
8271 Append_Entity (S, Current_Scope);
8274 Set_Public_Status (S);
8276 if Debug_Flag_E then
8277 Write_Str ("New overloaded entity chain: ");
8278 Write_Name (Chars (S));
8281 while Present (E) loop
8282 Write_Str (" "); Write_Int (Int (E));
8289 -- Generate warning for hiding
8292 and then Comes_From_Source (S)
8293 and then In_Extended_Main_Source_Unit (S)
8300 -- Warn unless genuine overloading. Do not emit warning on
8301 -- hiding predefined operators in Standard (these are either an
8302 -- (artifact of our implicit declarations, or simple noise) but
8303 -- keep warning on a operator defined on a local subtype, because
8304 -- of the real danger that different operators may be applied in
8305 -- various parts of the program.
8307 -- Note that if E and S have the same scope, there is never any
8308 -- hiding. Either the two conflict, and the program is illegal,
8309 -- or S is overriding an implicit inherited subprogram.
8311 if Scope (E) /= Scope (S)
8312 and then (not Is_Overloadable (E)
8313 or else Subtype_Conformant (E, S))
8314 and then (Is_Immediately_Visible (E)
8315 or else Is_Potentially_Use_Visible (S))
8317 if Scope (E) = Standard_Standard then
8318 if Nkind (S) = N_Defining_Operator_Symbol
8319 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8321 and then Matches_Predefined_Op
8324 ("declaration of & hides predefined operator?h?", S);
8327 -- E not immediately within Standard
8330 Error_Msg_Sloc := Sloc (E);
8331 Error_Msg_N ("declaration of & hides one #?h?", S);
8336 end Enter_Overloaded_Entity;
8338 -----------------------------
8339 -- Check_Untagged_Equality --
8340 -----------------------------
8342 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8343 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8344 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8348 -- This check applies only if we have a subprogram declaration with an
8349 -- untagged record type.
8351 if Nkind (Decl) /= N_Subprogram_Declaration
8352 or else not Is_Record_Type (Typ)
8353 or else Is_Tagged_Type (Typ)
8358 -- In Ada 2012 case, we will output errors or warnings depending on
8359 -- the setting of debug flag -gnatd.E.
8361 if Ada_Version >= Ada_2012 then
8362 Error_Msg_Warn := Debug_Flag_Dot_EE;
8364 -- In earlier versions of Ada, nothing to do unless we are warning on
8365 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8368 if not Warn_On_Ada_2012_Compatibility then
8373 -- Cases where the type has already been frozen
8375 if Is_Frozen (Typ) then
8377 -- If the type is not declared in a package, or if we are in the body
8378 -- of the package or in some other scope, the new operation is not
8379 -- primitive, and therefore legal, though suspicious. Should we
8380 -- generate a warning in this case ???
8382 if Ekind (Scope (Typ)) /= E_Package
8383 or else Scope (Typ) /= Current_Scope
8387 -- If the type is a generic actual (sub)type, the operation is not
8388 -- primitive either because the base type is declared elsewhere.
8390 elsif Is_Generic_Actual_Type (Typ) then
8393 -- Here we have a definite error of declaration after freezing
8396 if Ada_Version >= Ada_2012 then
8398 ("equality operator must be declared before type & is "
8399 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8401 -- In Ada 2012 mode with error turned to warning, output one
8402 -- more warning to warn that the equality operation may not
8403 -- compose. This is the consequence of ignoring the error.
8405 if Error_Msg_Warn then
8406 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8411 ("equality operator must be declared before type& is "
8412 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8415 -- If we are in the package body, we could just move the
8416 -- declaration to the package spec, so add a message saying that.
8418 if In_Package_Body (Scope (Typ)) then
8419 if Ada_Version >= Ada_2012 then
8421 ("\move declaration to package spec<<", Eq_Op);
8424 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8427 -- Otherwise try to find the freezing point
8430 Obj_Decl := Next (Parent (Typ));
8431 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8432 if Nkind (Obj_Decl) = N_Object_Declaration
8433 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8435 -- Freezing point, output warnings
8437 if Ada_Version >= Ada_2012 then
8439 ("type& is frozen by declaration??", Obj_Decl, Typ);
8441 ("\an equality operator cannot be declared after "
8446 ("type& is frozen by declaration (Ada 2012)?y?",
8449 ("\an equality operator cannot be declared after "
8450 & "this point (Ada 2012)?y?",
8462 -- Here if type is not frozen yet. It is illegal to have a primitive
8463 -- equality declared in the private part if the type is visible.
8465 elsif not In_Same_List (Parent (Typ), Decl)
8466 and then not Is_Limited_Type (Typ)
8468 -- Shouldn't we give an RM reference here???
8470 if Ada_Version >= Ada_2012 then
8472 ("equality operator appears too late<<", Eq_Op);
8475 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8478 -- No error detected
8483 end Check_Untagged_Equality;
8485 -----------------------------
8486 -- Find_Corresponding_Spec --
8487 -----------------------------
8489 function Find_Corresponding_Spec
8491 Post_Error : Boolean := True) return Entity_Id
8493 Spec : constant Node_Id := Specification (N);
8494 Designator : constant Entity_Id := Defining_Entity (Spec);
8498 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8499 -- Even if fully conformant, a body may depend on a generic actual when
8500 -- the spec does not, or vice versa, in which case they were distinct
8501 -- entities in the generic.
8503 -------------------------------
8504 -- Different_Generic_Profile --
8505 -------------------------------
8507 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8510 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8511 -- Check that the types of corresponding formals have the same
8512 -- generic actual if any. We have to account for subtypes of a
8513 -- generic formal, declared between a spec and a body, which may
8514 -- appear distinct in an instance but matched in the generic, and
8515 -- the subtype may be used either in the spec or the body of the
8516 -- subprogram being checked.
8518 -------------------------
8519 -- Same_Generic_Actual --
8520 -------------------------
8522 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8524 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8525 -- Predicate to check whether S1 is a subtype of S2 in the source
8528 -------------------------
8529 -- Is_Declared_Subtype --
8530 -------------------------
8532 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8534 return Comes_From_Source (Parent (S1))
8535 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8536 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8537 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8538 end Is_Declared_Subtype;
8540 -- Start of processing for Same_Generic_Actual
8543 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8544 or else Is_Declared_Subtype (T1, T2)
8545 or else Is_Declared_Subtype (T2, T1);
8546 end Same_Generic_Actual;
8548 -- Start of processing for Different_Generic_Profile
8551 if not In_Instance then
8554 elsif Ekind (E) = E_Function
8555 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8560 F1 := First_Formal (Designator);
8561 F2 := First_Formal (E);
8562 while Present (F1) loop
8563 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8572 end Different_Generic_Profile;
8574 -- Start of processing for Find_Corresponding_Spec
8577 E := Current_Entity (Designator);
8578 while Present (E) loop
8580 -- We are looking for a matching spec. It must have the same scope,
8581 -- and the same name, and either be type conformant, or be the case
8582 -- of a library procedure spec and its body (which belong to one
8583 -- another regardless of whether they are type conformant or not).
8585 if Scope (E) = Current_Scope then
8586 if Current_Scope = Standard_Standard
8587 or else (Ekind (E) = Ekind (Designator)
8588 and then Type_Conformant (E, Designator))
8590 -- Within an instantiation, we know that spec and body are
8591 -- subtype conformant, because they were subtype conformant in
8592 -- the generic. We choose the subtype-conformant entity here as
8593 -- well, to resolve spurious ambiguities in the instance that
8594 -- were not present in the generic (i.e. when two different
8595 -- types are given the same actual). If we are looking for a
8596 -- spec to match a body, full conformance is expected.
8600 -- Inherit the convention and "ghostness" of the matching
8601 -- spec to ensure proper full and subtype conformance.
8603 Set_Convention (Designator, Convention (E));
8605 -- Skip past subprogram bodies and subprogram renamings that
8606 -- may appear to have a matching spec, but that aren't fully
8607 -- conformant with it. That can occur in cases where an
8608 -- actual type causes unrelated homographs in the instance.
8610 if Nkind_In (N, N_Subprogram_Body,
8611 N_Subprogram_Renaming_Declaration)
8612 and then Present (Homonym (E))
8613 and then not Fully_Conformant (Designator, E)
8617 elsif not Subtype_Conformant (Designator, E) then
8620 elsif Different_Generic_Profile (E) then
8625 -- Ada 2012 (AI05-0165): For internally generated bodies of
8626 -- null procedures locate the internally generated spec. We
8627 -- enforce mode conformance since a tagged type may inherit
8628 -- from interfaces several null primitives which differ only
8629 -- in the mode of the formals.
8631 if not (Comes_From_Source (E))
8632 and then Is_Null_Procedure (E)
8633 and then not Mode_Conformant (Designator, E)
8637 -- For null procedures coming from source that are completions,
8638 -- analysis of the generated body will establish the link.
8640 elsif Comes_From_Source (E)
8641 and then Nkind (Spec) = N_Procedure_Specification
8642 and then Null_Present (Spec)
8646 -- Expression functions can be completions, but cannot be
8647 -- completed by an explicit body.
8649 elsif Comes_From_Source (E)
8650 and then Comes_From_Source (N)
8651 and then Nkind (N) = N_Subprogram_Body
8652 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8653 N_Expression_Function
8655 Error_Msg_Sloc := Sloc (E);
8656 Error_Msg_N ("body conflicts with expression function#", N);
8659 elsif not Has_Completion (E) then
8660 if Nkind (N) /= N_Subprogram_Body_Stub then
8661 Set_Corresponding_Spec (N, E);
8664 Set_Has_Completion (E);
8667 elsif Nkind (Parent (N)) = N_Subunit then
8669 -- If this is the proper body of a subunit, the completion
8670 -- flag is set when analyzing the stub.
8674 -- If E is an internal function with a controlling result that
8675 -- was created for an operation inherited by a null extension,
8676 -- it may be overridden by a body without a previous spec (one
8677 -- more reason why these should be shunned). In that case we
8678 -- remove the generated body if present, because the current
8679 -- one is the explicit overriding.
8681 elsif Ekind (E) = E_Function
8682 and then Ada_Version >= Ada_2005
8683 and then not Comes_From_Source (E)
8684 and then Has_Controlling_Result (E)
8685 and then Is_Null_Extension (Etype (E))
8686 and then Comes_From_Source (Spec)
8688 Set_Has_Completion (E, False);
8691 and then Nkind (Parent (E)) = N_Function_Specification
8694 (Unit_Declaration_Node
8695 (Corresponding_Body (Unit_Declaration_Node (E))));
8699 -- If expansion is disabled, or if the wrapper function has
8700 -- not been generated yet, this a late body overriding an
8701 -- inherited operation, or it is an overriding by some other
8702 -- declaration before the controlling result is frozen. In
8703 -- either case this is a declaration of a new entity.
8709 -- If the body already exists, then this is an error unless
8710 -- the previous declaration is the implicit declaration of a
8711 -- derived subprogram. It is also legal for an instance to
8712 -- contain type conformant overloadable declarations (but the
8713 -- generic declaration may not), per 8.3(26/2).
8715 elsif No (Alias (E))
8716 and then not Is_Intrinsic_Subprogram (E)
8717 and then not In_Instance
8720 Error_Msg_Sloc := Sloc (E);
8722 if Is_Imported (E) then
8724 ("body not allowed for imported subprogram & declared#",
8727 Error_Msg_NE ("duplicate body for & declared#", N, E);
8731 -- Child units cannot be overloaded, so a conformance mismatch
8732 -- between body and a previous spec is an error.
8734 elsif Is_Child_Unit (E)
8736 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8738 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8743 ("body of child unit does not match previous declaration", N);
8751 -- On exit, we know that no previous declaration of subprogram exists
8754 end Find_Corresponding_Spec;
8756 ----------------------
8757 -- Fully_Conformant --
8758 ----------------------
8760 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8763 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8765 end Fully_Conformant;
8767 ----------------------------------
8768 -- Fully_Conformant_Expressions --
8769 ----------------------------------
8771 function Fully_Conformant_Expressions
8772 (Given_E1 : Node_Id;
8773 Given_E2 : Node_Id) return Boolean
8775 E1 : constant Node_Id := Original_Node (Given_E1);
8776 E2 : constant Node_Id := Original_Node (Given_E2);
8777 -- We always test conformance on original nodes, since it is possible
8778 -- for analysis and/or expansion to make things look as though they
8779 -- conform when they do not, e.g. by converting 1+2 into 3.
8781 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8782 renames Fully_Conformant_Expressions;
8784 function FCL (L1, L2 : List_Id) return Boolean;
8785 -- Compare elements of two lists for conformance. Elements have to be
8786 -- conformant, and actuals inserted as default parameters do not match
8787 -- explicit actuals with the same value.
8789 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8790 -- Compare an operator node with a function call
8796 function FCL (L1, L2 : List_Id) return Boolean is
8800 if L1 = No_List then
8806 if L2 = No_List then
8812 -- Compare two lists, skipping rewrite insertions (we want to compare
8813 -- the original trees, not the expanded versions).
8816 if Is_Rewrite_Insertion (N1) then
8818 elsif Is_Rewrite_Insertion (N2) then
8824 elsif not FCE (N1, N2) then
8837 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8838 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8843 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8848 Act := First (Actuals);
8850 if Nkind (Op_Node) in N_Binary_Op then
8851 if not FCE (Left_Opnd (Op_Node), Act) then
8858 return Present (Act)
8859 and then FCE (Right_Opnd (Op_Node), Act)
8860 and then No (Next (Act));
8864 -- Start of processing for Fully_Conformant_Expressions
8867 -- Nonconformant if paren count does not match. Note: if some idiot
8868 -- complains that we don't do this right for more than 3 levels of
8869 -- parentheses, they will be treated with the respect they deserve.
8871 if Paren_Count (E1) /= Paren_Count (E2) then
8874 -- If same entities are referenced, then they are conformant even if
8875 -- they have different forms (RM 8.3.1(19-20)).
8877 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8878 if Present (Entity (E1)) then
8879 return Entity (E1) = Entity (E2)
8881 -- One may be a discriminant that has been replaced by the
8882 -- corresponding discriminal.
8885 (Chars (Entity (E1)) = Chars (Entity (E2))
8886 and then Ekind (Entity (E1)) = E_Discriminant
8887 and then Ekind (Entity (E2)) = E_In_Parameter)
8889 -- The discriminant of a protected type is transformed into
8890 -- a local constant and then into a parameter of a protected
8894 (Ekind (Entity (E1)) = E_Constant
8895 and then Ekind (Entity (E2)) = E_In_Parameter
8896 and then Present (Discriminal_Link (Entity (E1)))
8897 and then Discriminal_Link (Entity (E1)) =
8898 Discriminal_Link (Entity (E2)))
8900 -- AI12-050: The loop variables of quantified expressions
8901 -- match if they have the same identifier, even though they
8902 -- are different entities.
8905 (Chars (Entity (E1)) = Chars (Entity (E2))
8906 and then Ekind (Entity (E1)) = E_Loop_Parameter
8907 and then Ekind (Entity (E2)) = E_Loop_Parameter);
8909 elsif Nkind (E1) = N_Expanded_Name
8910 and then Nkind (E2) = N_Expanded_Name
8911 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8912 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8914 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8917 -- Identifiers in component associations don't always have
8918 -- entities, but their names must conform.
8920 return Nkind (E1) = N_Identifier
8921 and then Nkind (E2) = N_Identifier
8922 and then Chars (E1) = Chars (E2);
8925 elsif Nkind (E1) = N_Character_Literal
8926 and then Nkind (E2) = N_Expanded_Name
8928 return Nkind (Selector_Name (E2)) = N_Character_Literal
8929 and then Chars (E1) = Chars (Selector_Name (E2));
8931 elsif Nkind (E2) = N_Character_Literal
8932 and then Nkind (E1) = N_Expanded_Name
8934 return Nkind (Selector_Name (E1)) = N_Character_Literal
8935 and then Chars (E2) = Chars (Selector_Name (E1));
8937 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8938 return FCO (E1, E2);
8940 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8941 return FCO (E2, E1);
8943 -- Otherwise we must have the same syntactic entity
8945 elsif Nkind (E1) /= Nkind (E2) then
8948 -- At this point, we specialize by node type
8954 FCL (Expressions (E1), Expressions (E2))
8956 FCL (Component_Associations (E1),
8957 Component_Associations (E2));
8960 if Nkind (Expression (E1)) = N_Qualified_Expression
8962 Nkind (Expression (E2)) = N_Qualified_Expression
8964 return FCE (Expression (E1), Expression (E2));
8966 -- Check that the subtype marks and any constraints
8971 Indic1 : constant Node_Id := Expression (E1);
8972 Indic2 : constant Node_Id := Expression (E2);
8977 if Nkind (Indic1) /= N_Subtype_Indication then
8979 Nkind (Indic2) /= N_Subtype_Indication
8980 and then Entity (Indic1) = Entity (Indic2);
8982 elsif Nkind (Indic2) /= N_Subtype_Indication then
8984 Nkind (Indic1) /= N_Subtype_Indication
8985 and then Entity (Indic1) = Entity (Indic2);
8988 if Entity (Subtype_Mark (Indic1)) /=
8989 Entity (Subtype_Mark (Indic2))
8994 Elt1 := First (Constraints (Constraint (Indic1)));
8995 Elt2 := First (Constraints (Constraint (Indic2)));
8996 while Present (Elt1) and then Present (Elt2) loop
8997 if not FCE (Elt1, Elt2) then
9010 when N_Attribute_Reference =>
9012 Attribute_Name (E1) = Attribute_Name (E2)
9013 and then FCL (Expressions (E1), Expressions (E2));
9017 Entity (E1) = Entity (E2)
9018 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9019 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9021 when N_Membership_Test
9025 FCE (Left_Opnd (E1), Left_Opnd (E2))
9027 FCE (Right_Opnd (E1), Right_Opnd (E2));
9029 when N_Case_Expression =>
9035 if not FCE (Expression (E1), Expression (E2)) then
9039 Alt1 := First (Alternatives (E1));
9040 Alt2 := First (Alternatives (E2));
9042 if Present (Alt1) /= Present (Alt2) then
9044 elsif No (Alt1) then
9048 if not FCE (Expression (Alt1), Expression (Alt2))
9049 or else not FCL (Discrete_Choices (Alt1),
9050 Discrete_Choices (Alt2))
9061 when N_Character_Literal =>
9063 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9065 when N_Component_Association =>
9067 FCL (Choices (E1), Choices (E2))
9069 FCE (Expression (E1), Expression (E2));
9071 when N_Explicit_Dereference =>
9073 FCE (Prefix (E1), Prefix (E2));
9075 when N_Extension_Aggregate =>
9077 FCL (Expressions (E1), Expressions (E2))
9078 and then Null_Record_Present (E1) =
9079 Null_Record_Present (E2)
9080 and then FCL (Component_Associations (E1),
9081 Component_Associations (E2));
9083 when N_Function_Call =>
9085 FCE (Name (E1), Name (E2))
9087 FCL (Parameter_Associations (E1),
9088 Parameter_Associations (E2));
9090 when N_If_Expression =>
9092 FCL (Expressions (E1), Expressions (E2));
9094 when N_Indexed_Component =>
9096 FCE (Prefix (E1), Prefix (E2))
9098 FCL (Expressions (E1), Expressions (E2));
9100 when N_Integer_Literal =>
9101 return (Intval (E1) = Intval (E2));
9106 when N_Operator_Symbol =>
9108 Chars (E1) = Chars (E2);
9110 when N_Others_Choice =>
9113 when N_Parameter_Association =>
9115 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9116 and then FCE (Explicit_Actual_Parameter (E1),
9117 Explicit_Actual_Parameter (E2));
9119 when N_Qualified_Expression
9121 | N_Unchecked_Type_Conversion
9124 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9126 FCE (Expression (E1), Expression (E2));
9128 when N_Quantified_Expression =>
9129 if not FCE (Condition (E1), Condition (E2)) then
9133 if Present (Loop_Parameter_Specification (E1))
9134 and then Present (Loop_Parameter_Specification (E2))
9137 L1 : constant Node_Id :=
9138 Loop_Parameter_Specification (E1);
9139 L2 : constant Node_Id :=
9140 Loop_Parameter_Specification (E2);
9144 Reverse_Present (L1) = Reverse_Present (L2)
9146 FCE (Defining_Identifier (L1),
9147 Defining_Identifier (L2))
9149 FCE (Discrete_Subtype_Definition (L1),
9150 Discrete_Subtype_Definition (L2));
9153 elsif Present (Iterator_Specification (E1))
9154 and then Present (Iterator_Specification (E2))
9157 I1 : constant Node_Id := Iterator_Specification (E1);
9158 I2 : constant Node_Id := Iterator_Specification (E2);
9162 FCE (Defining_Identifier (I1),
9163 Defining_Identifier (I2))
9165 Of_Present (I1) = Of_Present (I2)
9167 Reverse_Present (I1) = Reverse_Present (I2)
9168 and then FCE (Name (I1), Name (I2))
9169 and then FCE (Subtype_Indication (I1),
9170 Subtype_Indication (I2));
9173 -- The quantified expressions used different specifications to
9174 -- walk their respective ranges.
9182 FCE (Low_Bound (E1), Low_Bound (E2))
9184 FCE (High_Bound (E1), High_Bound (E2));
9186 when N_Real_Literal =>
9187 return (Realval (E1) = Realval (E2));
9189 when N_Selected_Component =>
9191 FCE (Prefix (E1), Prefix (E2))
9193 FCE (Selector_Name (E1), Selector_Name (E2));
9197 FCE (Prefix (E1), Prefix (E2))
9199 FCE (Discrete_Range (E1), Discrete_Range (E2));
9201 when N_String_Literal =>
9203 S1 : constant String_Id := Strval (E1);
9204 S2 : constant String_Id := Strval (E2);
9205 L1 : constant Nat := String_Length (S1);
9206 L2 : constant Nat := String_Length (S2);
9213 for J in 1 .. L1 loop
9214 if Get_String_Char (S1, J) /=
9215 Get_String_Char (S2, J)
9227 Entity (E1) = Entity (E2)
9229 FCE (Right_Opnd (E1), Right_Opnd (E2));
9231 -- All other node types cannot appear in this context. Strictly
9232 -- we should raise a fatal internal error. Instead we just ignore
9233 -- the nodes. This means that if anyone makes a mistake in the
9234 -- expander and mucks an expression tree irretrievably, the result
9235 -- will be a failure to detect a (probably very obscure) case
9236 -- of non-conformance, which is better than bombing on some
9237 -- case where two expressions do in fact conform.
9243 end Fully_Conformant_Expressions;
9245 ----------------------------------------
9246 -- Fully_Conformant_Discrete_Subtypes --
9247 ----------------------------------------
9249 function Fully_Conformant_Discrete_Subtypes
9250 (Given_S1 : Node_Id;
9251 Given_S2 : Node_Id) return Boolean
9253 S1 : constant Node_Id := Original_Node (Given_S1);
9254 S2 : constant Node_Id := Original_Node (Given_S2);
9256 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9257 -- Special-case for a bound given by a discriminant, which in the body
9258 -- is replaced with the discriminal of the enclosing type.
9260 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9261 -- Check both bounds
9263 -----------------------
9264 -- Conforming_Bounds --
9265 -----------------------
9267 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9269 if Is_Entity_Name (B1)
9270 and then Is_Entity_Name (B2)
9271 and then Ekind (Entity (B1)) = E_Discriminant
9273 return Chars (B1) = Chars (B2);
9276 return Fully_Conformant_Expressions (B1, B2);
9278 end Conforming_Bounds;
9280 -----------------------
9281 -- Conforming_Ranges --
9282 -----------------------
9284 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9287 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9289 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9290 end Conforming_Ranges;
9292 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9295 if Nkind (S1) /= Nkind (S2) then
9298 elsif Is_Entity_Name (S1) then
9299 return Entity (S1) = Entity (S2);
9301 elsif Nkind (S1) = N_Range then
9302 return Conforming_Ranges (S1, S2);
9304 elsif Nkind (S1) = N_Subtype_Indication then
9306 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9309 (Range_Expression (Constraint (S1)),
9310 Range_Expression (Constraint (S2)));
9314 end Fully_Conformant_Discrete_Subtypes;
9316 --------------------
9317 -- Install_Entity --
9318 --------------------
9320 procedure Install_Entity (E : Entity_Id) is
9321 Prev : constant Entity_Id := Current_Entity (E);
9323 Set_Is_Immediately_Visible (E);
9324 Set_Current_Entity (E);
9325 Set_Homonym (E, Prev);
9328 ---------------------
9329 -- Install_Formals --
9330 ---------------------
9332 procedure Install_Formals (Id : Entity_Id) is
9335 F := First_Formal (Id);
9336 while Present (F) loop
9340 end Install_Formals;
9342 -----------------------------
9343 -- Is_Interface_Conformant --
9344 -----------------------------
9346 function Is_Interface_Conformant
9347 (Tagged_Type : Entity_Id;
9348 Iface_Prim : Entity_Id;
9349 Prim : Entity_Id) return Boolean
9351 -- The operation may in fact be an inherited (implicit) operation
9352 -- rather than the original interface primitive, so retrieve the
9353 -- ultimate ancestor.
9355 Iface : constant Entity_Id :=
9356 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9357 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9359 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9360 -- Return the controlling formal of Prim
9362 ------------------------
9363 -- Controlling_Formal --
9364 ------------------------
9366 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9370 E := First_Entity (Prim);
9371 while Present (E) loop
9372 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9380 end Controlling_Formal;
9384 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9385 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9387 -- Start of processing for Is_Interface_Conformant
9390 pragma Assert (Is_Subprogram (Iface_Prim)
9391 and then Is_Subprogram (Prim)
9392 and then Is_Dispatching_Operation (Iface_Prim)
9393 and then Is_Dispatching_Operation (Prim));
9395 pragma Assert (Is_Interface (Iface)
9396 or else (Present (Alias (Iface_Prim))
9399 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9401 if Prim = Iface_Prim
9402 or else not Is_Subprogram (Prim)
9403 or else Ekind (Prim) /= Ekind (Iface_Prim)
9404 or else not Is_Dispatching_Operation (Prim)
9405 or else Scope (Prim) /= Scope (Tagged_Type)
9407 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9408 or else not Primitive_Names_Match (Iface_Prim, Prim)
9412 -- The mode of the controlling formals must match
9414 elsif Present (Iface_Ctrl_F)
9415 and then Present (Prim_Ctrl_F)
9416 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9420 -- Case of a procedure, or a function whose result type matches the
9421 -- result type of the interface primitive, or a function that has no
9422 -- controlling result (I or access I).
9424 elsif Ekind (Iface_Prim) = E_Procedure
9425 or else Etype (Prim) = Etype (Iface_Prim)
9426 or else not Has_Controlling_Result (Prim)
9428 return Type_Conformant
9429 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9431 -- Case of a function returning an interface, or an access to one. Check
9432 -- that the return types correspond.
9434 elsif Implements_Interface (Typ, Iface) then
9435 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9437 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9442 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9443 Skip_Controlling_Formals => True);
9449 end Is_Interface_Conformant;
9451 ---------------------------------
9452 -- Is_Non_Overriding_Operation --
9453 ---------------------------------
9455 function Is_Non_Overriding_Operation
9456 (Prev_E : Entity_Id;
9457 New_E : Entity_Id) return Boolean
9461 G_Typ : Entity_Id := Empty;
9463 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9464 -- If F_Type is a derived type associated with a generic actual subtype,
9465 -- then return its Generic_Parent_Type attribute, else return Empty.
9467 function Types_Correspond
9468 (P_Type : Entity_Id;
9469 N_Type : Entity_Id) return Boolean;
9470 -- Returns true if and only if the types (or designated types in the
9471 -- case of anonymous access types) are the same or N_Type is derived
9472 -- directly or indirectly from P_Type.
9474 -----------------------------
9475 -- Get_Generic_Parent_Type --
9476 -----------------------------
9478 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9484 if Is_Derived_Type (F_Typ)
9485 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9487 -- The tree must be traversed to determine the parent subtype in
9488 -- the generic unit, which unfortunately isn't always available
9489 -- via semantic attributes. ??? (Note: The use of Original_Node
9490 -- is needed for cases where a full derived type has been
9493 -- If the parent type is a scalar type, the derivation creates
9494 -- an anonymous base type for it, and the source type is its
9497 if Is_Scalar_Type (F_Typ)
9498 and then not Comes_From_Source (F_Typ)
9502 (Original_Node (Parent (First_Subtype (F_Typ))));
9504 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9506 if Nkind (Defn) = N_Derived_Type_Definition then
9507 Indic := Subtype_Indication (Defn);
9509 if Nkind (Indic) = N_Subtype_Indication then
9510 G_Typ := Entity (Subtype_Mark (Indic));
9512 G_Typ := Entity (Indic);
9515 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9516 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9518 return Generic_Parent_Type (Parent (G_Typ));
9524 end Get_Generic_Parent_Type;
9526 ----------------------
9527 -- Types_Correspond --
9528 ----------------------
9530 function Types_Correspond
9531 (P_Type : Entity_Id;
9532 N_Type : Entity_Id) return Boolean
9534 Prev_Type : Entity_Id := Base_Type (P_Type);
9535 New_Type : Entity_Id := Base_Type (N_Type);
9538 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9539 Prev_Type := Designated_Type (Prev_Type);
9542 if Ekind (New_Type) = E_Anonymous_Access_Type then
9543 New_Type := Designated_Type (New_Type);
9546 if Prev_Type = New_Type then
9549 elsif not Is_Class_Wide_Type (New_Type) then
9550 while Etype (New_Type) /= New_Type loop
9551 New_Type := Etype (New_Type);
9553 if New_Type = Prev_Type then
9559 end Types_Correspond;
9561 -- Start of processing for Is_Non_Overriding_Operation
9564 -- In the case where both operations are implicit derived subprograms
9565 -- then neither overrides the other. This can only occur in certain
9566 -- obscure cases (e.g., derivation from homographs created in a generic
9569 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9572 elsif Ekind (Current_Scope) = E_Package
9573 and then Is_Generic_Instance (Current_Scope)
9574 and then In_Private_Part (Current_Scope)
9575 and then Comes_From_Source (New_E)
9577 -- We examine the formals and result type of the inherited operation,
9578 -- to determine whether their type is derived from (the instance of)
9579 -- a generic type. The first such formal or result type is the one
9582 Formal := First_Formal (Prev_E);
9584 while Present (Formal) loop
9585 F_Typ := Base_Type (Etype (Formal));
9587 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9588 F_Typ := Designated_Type (F_Typ);
9591 G_Typ := Get_Generic_Parent_Type (F_Typ);
9592 exit when Present (G_Typ);
9594 Next_Formal (Formal);
9597 -- If the function dispatches on result check the result type
9599 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9600 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9607 -- If the generic type is a private type, then the original operation
9608 -- was not overriding in the generic, because there was no primitive
9609 -- operation to override.
9611 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9612 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9613 N_Formal_Private_Type_Definition
9617 -- The generic parent type is the ancestor of a formal derived
9618 -- type declaration. We need to check whether it has a primitive
9619 -- operation that should be overridden by New_E in the generic.
9623 P_Formal : Entity_Id;
9624 N_Formal : Entity_Id;
9628 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9631 while Present (Prim_Elt) loop
9632 P_Prim := Node (Prim_Elt);
9634 if Chars (P_Prim) = Chars (New_E)
9635 and then Ekind (P_Prim) = Ekind (New_E)
9637 P_Formal := First_Formal (P_Prim);
9638 N_Formal := First_Formal (New_E);
9639 while Present (P_Formal) and then Present (N_Formal) loop
9640 P_Typ := Etype (P_Formal);
9641 N_Typ := Etype (N_Formal);
9643 if not Types_Correspond (P_Typ, N_Typ) then
9647 Next_Entity (P_Formal);
9648 Next_Entity (N_Formal);
9651 -- Found a matching primitive operation belonging to the
9652 -- formal ancestor type, so the new subprogram is
9656 and then No (N_Formal)
9657 and then (Ekind (New_E) /= E_Function
9660 (Etype (P_Prim), Etype (New_E)))
9666 Next_Elmt (Prim_Elt);
9669 -- If no match found, then the new subprogram does not override
9670 -- in the generic (nor in the instance).
9672 -- If the type in question is not abstract, and the subprogram
9673 -- is, this will be an error if the new operation is in the
9674 -- private part of the instance. Emit a warning now, which will
9675 -- make the subsequent error message easier to understand.
9677 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9678 and then Is_Abstract_Subprogram (Prev_E)
9679 and then In_Private_Part (Current_Scope)
9681 Error_Msg_Node_2 := F_Typ;
9683 ("private operation& in generic unit does not override "
9684 & "any primitive operation of& (RM 12.3 (18))??",
9694 end Is_Non_Overriding_Operation;
9696 -------------------------------------
9697 -- List_Inherited_Pre_Post_Aspects --
9698 -------------------------------------
9700 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9702 if Opt.List_Inherited_Aspects
9703 and then Is_Subprogram_Or_Generic_Subprogram (E)
9706 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9711 for Index in Subps'Range loop
9712 Items := Contract (Subps (Index));
9714 if Present (Items) then
9715 Prag := Pre_Post_Conditions (Items);
9716 while Present (Prag) loop
9717 Error_Msg_Sloc := Sloc (Prag);
9719 if Class_Present (Prag)
9720 and then not Split_PPC (Prag)
9722 if Pragma_Name (Prag) = Name_Precondition then
9724 ("info: & inherits `Pre''Class` aspect from "
9728 ("info: & inherits `Post''Class` aspect from "
9733 Prag := Next_Pragma (Prag);
9739 end List_Inherited_Pre_Post_Aspects;
9741 ------------------------------
9742 -- Make_Inequality_Operator --
9743 ------------------------------
9745 -- S is the defining identifier of an equality operator. We build a
9746 -- subprogram declaration with the right signature. This operation is
9747 -- intrinsic, because it is always expanded as the negation of the
9748 -- call to the equality function.
9750 procedure Make_Inequality_Operator (S : Entity_Id) is
9751 Loc : constant Source_Ptr := Sloc (S);
9754 Op_Name : Entity_Id;
9756 FF : constant Entity_Id := First_Formal (S);
9757 NF : constant Entity_Id := Next_Formal (FF);
9760 -- Check that equality was properly defined, ignore call if not
9767 A : constant Entity_Id :=
9768 Make_Defining_Identifier (Sloc (FF),
9769 Chars => Chars (FF));
9771 B : constant Entity_Id :=
9772 Make_Defining_Identifier (Sloc (NF),
9773 Chars => Chars (NF));
9776 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9778 Formals := New_List (
9779 Make_Parameter_Specification (Loc,
9780 Defining_Identifier => A,
9782 New_Occurrence_Of (Etype (First_Formal (S)),
9783 Sloc (Etype (First_Formal (S))))),
9785 Make_Parameter_Specification (Loc,
9786 Defining_Identifier => B,
9788 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9789 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9792 Make_Subprogram_Declaration (Loc,
9794 Make_Function_Specification (Loc,
9795 Defining_Unit_Name => Op_Name,
9796 Parameter_Specifications => Formals,
9797 Result_Definition =>
9798 New_Occurrence_Of (Standard_Boolean, Loc)));
9800 -- Insert inequality right after equality if it is explicit or after
9801 -- the derived type when implicit. These entities are created only
9802 -- for visibility purposes, and eventually replaced in the course
9803 -- of expansion, so they do not need to be attached to the tree and
9804 -- seen by the back-end. Keeping them internal also avoids spurious
9805 -- freezing problems. The declaration is inserted in the tree for
9806 -- analysis, and removed afterwards. If the equality operator comes
9807 -- from an explicit declaration, attach the inequality immediately
9808 -- after. Else the equality is inherited from a derived type
9809 -- declaration, so insert inequality after that declaration.
9811 if No (Alias (S)) then
9812 Insert_After (Unit_Declaration_Node (S), Decl);
9813 elsif Is_List_Member (Parent (S)) then
9814 Insert_After (Parent (S), Decl);
9816 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9819 Mark_Rewrite_Insertion (Decl);
9820 Set_Is_Intrinsic_Subprogram (Op_Name);
9823 Set_Has_Completion (Op_Name);
9824 Set_Corresponding_Equality (Op_Name, S);
9825 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9827 end Make_Inequality_Operator;
9829 ----------------------
9830 -- May_Need_Actuals --
9831 ----------------------
9833 procedure May_Need_Actuals (Fun : Entity_Id) is
9838 F := First_Formal (Fun);
9840 while Present (F) loop
9841 if No (Default_Value (F)) then
9849 Set_Needs_No_Actuals (Fun, B);
9850 end May_Need_Actuals;
9852 ---------------------
9853 -- Mode_Conformant --
9854 ---------------------
9856 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9859 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9861 end Mode_Conformant;
9863 ---------------------------
9864 -- New_Overloaded_Entity --
9865 ---------------------------
9867 procedure New_Overloaded_Entity
9869 Derived_Type : Entity_Id := Empty)
9871 Overridden_Subp : Entity_Id := Empty;
9872 -- Set if the current scope has an operation that is type-conformant
9873 -- with S, and becomes hidden by S.
9875 Is_Primitive_Subp : Boolean;
9876 -- Set to True if the new subprogram is primitive
9879 -- Entity that S overrides
9881 Prev_Vis : Entity_Id := Empty;
9882 -- Predecessor of E in Homonym chain
9884 procedure Check_For_Primitive_Subprogram
9885 (Is_Primitive : out Boolean;
9886 Is_Overriding : Boolean := False);
9887 -- If the subprogram being analyzed is a primitive operation of the type
9888 -- of a formal or result, set the Has_Primitive_Operations flag on the
9889 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9890 -- corresponding flag on the entity itself for later use.
9892 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9893 -- True if a) E is a subprogram whose first formal is a concurrent type
9894 -- defined in the scope of E that has some entry or subprogram whose
9895 -- profile matches E, or b) E is an internally built dispatching
9896 -- subprogram of a protected type and there is a matching subprogram
9897 -- defined in the enclosing scope of the protected type, or c) E is
9898 -- an entry of a synchronized type and a matching procedure has been
9899 -- previously defined in the enclosing scope of the synchronized type.
9901 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9902 -- Check that E is declared in the private part of the current package,
9903 -- or in the package body, where it may hide a previous declaration.
9904 -- We can't use In_Private_Part by itself because this flag is also
9905 -- set when freezing entities, so we must examine the place of the
9906 -- declaration in the tree, and recognize wrapper packages as well.
9908 function Is_Overriding_Alias
9910 New_E : Entity_Id) return Boolean;
9911 -- Check whether new subprogram and old subprogram are both inherited
9912 -- from subprograms that have distinct dispatch table entries. This can
9913 -- occur with derivations from instances with accidental homonyms. The
9914 -- function is conservative given that the converse is only true within
9915 -- instances that contain accidental overloadings.
9917 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9918 -- Report conflict between entities S and E
9920 ------------------------------------
9921 -- Check_For_Primitive_Subprogram --
9922 ------------------------------------
9924 procedure Check_For_Primitive_Subprogram
9925 (Is_Primitive : out Boolean;
9926 Is_Overriding : Boolean := False)
9932 function Visible_Part_Type (T : Entity_Id) return Boolean;
9933 -- Returns true if T is declared in the visible part of the current
9934 -- package scope; otherwise returns false. Assumes that T is declared
9937 procedure Check_Private_Overriding (T : Entity_Id);
9938 -- Checks that if a primitive abstract subprogram of a visible
9939 -- abstract type is declared in a private part, then it must override
9940 -- an abstract subprogram declared in the visible part. Also checks
9941 -- that if a primitive function with a controlling result is declared
9942 -- in a private part, then it must override a function declared in
9943 -- the visible part.
9945 ------------------------------
9946 -- Check_Private_Overriding --
9947 ------------------------------
9949 procedure Check_Private_Overriding (T : Entity_Id) is
9950 function Overrides_Private_Part_Op return Boolean;
9951 -- This detects the special case where the overriding subprogram
9952 -- is overriding a subprogram that was declared in the same
9953 -- private part. That case is illegal by 3.9.3(10).
9955 function Overrides_Visible_Function
9956 (Partial_View : Entity_Id) return Boolean;
9957 -- True if S overrides a function in the visible part. The
9958 -- overridden function could be explicitly or implicitly declared.
9960 -------------------------------
9961 -- Overrides_Private_Part_Op --
9962 -------------------------------
9964 function Overrides_Private_Part_Op return Boolean is
9965 Over_Decl : constant Node_Id :=
9966 Unit_Declaration_Node (Overridden_Operation (S));
9967 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
9970 pragma Assert (Is_Overriding);
9972 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
9974 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
9976 return In_Same_List (Over_Decl, Subp_Decl);
9977 end Overrides_Private_Part_Op;
9979 --------------------------------
9980 -- Overrides_Visible_Function --
9981 --------------------------------
9983 function Overrides_Visible_Function
9984 (Partial_View : Entity_Id) return Boolean
9987 if not Is_Overriding or else not Has_Homonym (S) then
9991 if not Present (Partial_View) then
9995 -- Search through all the homonyms H of S in the current
9996 -- package spec, and return True if we find one that matches.
9997 -- Note that Parent (H) will be the declaration of the
9998 -- partial view of T for a match.
10001 H : Entity_Id := S;
10005 exit when not Present (H) or else Scope (H) /= Scope (S);
10009 N_Private_Extension_Declaration,
10010 N_Private_Type_Declaration)
10011 and then Defining_Identifier (Parent (H)) = Partial_View
10019 end Overrides_Visible_Function;
10021 -- Start of processing for Check_Private_Overriding
10024 if Is_Package_Or_Generic_Package (Current_Scope)
10025 and then In_Private_Part (Current_Scope)
10026 and then Visible_Part_Type (T)
10027 and then not In_Instance
10029 if Is_Abstract_Type (T)
10030 and then Is_Abstract_Subprogram (S)
10031 and then (not Is_Overriding
10032 or else not Is_Abstract_Subprogram (E)
10033 or else Overrides_Private_Part_Op)
10036 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10039 elsif Ekind (S) = E_Function then
10041 Partial_View : constant Entity_Id :=
10042 Incomplete_Or_Partial_View (T);
10045 if not Overrides_Visible_Function (Partial_View) then
10047 -- Here, S is "function ... return T;" declared in
10048 -- the private part, not overriding some visible
10049 -- operation. That's illegal in the tagged case
10050 -- (but not if the private type is untagged).
10052 if ((Present (Partial_View)
10053 and then Is_Tagged_Type (Partial_View))
10054 or else (not Present (Partial_View)
10055 and then Is_Tagged_Type (T)))
10056 and then T = Base_Type (Etype (S))
10059 ("private function with tagged result must"
10060 & " override visible-part function", S);
10062 ("\move subprogram to the visible part"
10063 & " (RM 3.9.3(10))", S);
10065 -- AI05-0073: extend this test to the case of a
10066 -- function with a controlling access result.
10068 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10069 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10071 not Is_Class_Wide_Type
10072 (Designated_Type (Etype (S)))
10073 and then Ada_Version >= Ada_2012
10076 ("private function with controlling access "
10077 & "result must override visible-part function",
10080 ("\move subprogram to the visible part"
10081 & " (RM 3.9.3(10))", S);
10087 end Check_Private_Overriding;
10089 -----------------------
10090 -- Visible_Part_Type --
10091 -----------------------
10093 function Visible_Part_Type (T : Entity_Id) return Boolean is
10094 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10098 -- If the entity is a private type, then it must be declared in a
10101 if Ekind (T) in Private_Kind then
10105 -- Otherwise, we traverse the visible part looking for its
10106 -- corresponding declaration. We cannot use the declaration
10107 -- node directly because in the private part the entity of a
10108 -- private type is the one in the full view, which does not
10109 -- indicate that it is the completion of something visible.
10111 N := First (Visible_Declarations (Specification (P)));
10112 while Present (N) loop
10113 if Nkind (N) = N_Full_Type_Declaration
10114 and then Present (Defining_Identifier (N))
10115 and then T = Defining_Identifier (N)
10119 elsif Nkind_In (N, N_Private_Type_Declaration,
10120 N_Private_Extension_Declaration)
10121 and then Present (Defining_Identifier (N))
10122 and then T = Full_View (Defining_Identifier (N))
10131 end Visible_Part_Type;
10133 -- Start of processing for Check_For_Primitive_Subprogram
10136 Is_Primitive := False;
10138 if not Comes_From_Source (S) then
10141 -- If subprogram is at library level, it is not primitive operation
10143 elsif Current_Scope = Standard_Standard then
10146 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10147 and then not In_Package_Body (Current_Scope))
10148 or else Is_Overriding
10150 -- For function, check return type
10152 if Ekind (S) = E_Function then
10153 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10154 F_Typ := Designated_Type (Etype (S));
10156 F_Typ := Etype (S);
10159 B_Typ := Base_Type (F_Typ);
10161 if Scope (B_Typ) = Current_Scope
10162 and then not Is_Class_Wide_Type (B_Typ)
10163 and then not Is_Generic_Type (B_Typ)
10165 Is_Primitive := True;
10166 Set_Has_Primitive_Operations (B_Typ);
10167 Set_Is_Primitive (S);
10168 Check_Private_Overriding (B_Typ);
10170 -- The Ghost policy in effect at the point of declaration
10171 -- or a tagged type and a primitive operation must match
10172 -- (SPARK RM 6.9(16)).
10174 Check_Ghost_Primitive (S, B_Typ);
10178 -- For all subprograms, check formals
10180 Formal := First_Formal (S);
10181 while Present (Formal) loop
10182 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10183 F_Typ := Designated_Type (Etype (Formal));
10185 F_Typ := Etype (Formal);
10188 B_Typ := Base_Type (F_Typ);
10190 if Ekind (B_Typ) = E_Access_Subtype then
10191 B_Typ := Base_Type (B_Typ);
10194 if Scope (B_Typ) = Current_Scope
10195 and then not Is_Class_Wide_Type (B_Typ)
10196 and then not Is_Generic_Type (B_Typ)
10198 Is_Primitive := True;
10199 Set_Is_Primitive (S);
10200 Set_Has_Primitive_Operations (B_Typ);
10201 Check_Private_Overriding (B_Typ);
10203 -- The Ghost policy in effect at the point of declaration
10204 -- of a tagged type and a primitive operation must match
10205 -- (SPARK RM 6.9(16)).
10207 Check_Ghost_Primitive (S, B_Typ);
10210 Next_Formal (Formal);
10213 -- Special case: An equality function can be redefined for a type
10214 -- occurring in a declarative part, and won't otherwise be treated as
10215 -- a primitive because it doesn't occur in a package spec and doesn't
10216 -- override an inherited subprogram. It's important that we mark it
10217 -- primitive so it can be returned by Collect_Primitive_Operations
10218 -- and be used in composing the equality operation of later types
10219 -- that have a component of the type.
10221 elsif Chars (S) = Name_Op_Eq
10222 and then Etype (S) = Standard_Boolean
10224 B_Typ := Base_Type (Etype (First_Formal (S)));
10226 if Scope (B_Typ) = Current_Scope
10228 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10229 and then not Is_Limited_Type (B_Typ)
10231 Is_Primitive := True;
10232 Set_Is_Primitive (S);
10233 Set_Has_Primitive_Operations (B_Typ);
10234 Check_Private_Overriding (B_Typ);
10236 -- The Ghost policy in effect at the point of declaration of a
10237 -- tagged type and a primitive operation must match
10238 -- (SPARK RM 6.9(16)).
10240 Check_Ghost_Primitive (S, B_Typ);
10243 end Check_For_Primitive_Subprogram;
10245 --------------------------------------
10246 -- Has_Matching_Entry_Or_Subprogram --
10247 --------------------------------------
10249 function Has_Matching_Entry_Or_Subprogram
10250 (E : Entity_Id) return Boolean
10252 function Check_Conforming_Parameters
10253 (E1_Param : Node_Id;
10254 E2_Param : Node_Id) return Boolean;
10255 -- Starting from the given parameters, check that all the parameters
10256 -- of two entries or subprograms are subtype conformant. Used to skip
10257 -- the check on the controlling argument.
10259 function Matching_Entry_Or_Subprogram
10260 (Conc_Typ : Entity_Id;
10261 Subp : Entity_Id) return Entity_Id;
10262 -- Return the first entry or subprogram of the given concurrent type
10263 -- whose name matches the name of Subp and has a profile conformant
10264 -- with Subp; return Empty if not found.
10266 function Matching_Dispatching_Subprogram
10267 (Conc_Typ : Entity_Id;
10268 Ent : Entity_Id) return Entity_Id;
10269 -- Return the first dispatching primitive of Conc_Type defined in the
10270 -- enclosing scope of Conc_Type (i.e. before the full definition of
10271 -- this concurrent type) whose name matches the entry Ent and has a
10272 -- profile conformant with the profile of the corresponding (not yet
10273 -- built) dispatching primitive of Ent; return Empty if not found.
10275 function Matching_Original_Protected_Subprogram
10276 (Prot_Typ : Entity_Id;
10277 Subp : Entity_Id) return Entity_Id;
10278 -- Return the first subprogram defined in the enclosing scope of
10279 -- Prot_Typ (before the full definition of this protected type)
10280 -- whose name matches the original name of Subp and has a profile
10281 -- conformant with the profile of Subp; return Empty if not found.
10283 ---------------------------------
10284 -- Check_Confirming_Parameters --
10285 ---------------------------------
10287 function Check_Conforming_Parameters
10288 (E1_Param : Node_Id;
10289 E2_Param : Node_Id) return Boolean
10291 Param_E1 : Node_Id := E1_Param;
10292 Param_E2 : Node_Id := E2_Param;
10295 while Present (Param_E1) and then Present (Param_E2) loop
10296 if Ekind (Defining_Identifier (Param_E1)) /=
10297 Ekind (Defining_Identifier (Param_E2))
10300 (Find_Parameter_Type (Param_E1),
10301 Find_Parameter_Type (Param_E2),
10302 Subtype_Conformant)
10311 -- The candidate is not valid if one of the two lists contains
10312 -- more parameters than the other
10314 return No (Param_E1) and then No (Param_E2);
10315 end Check_Conforming_Parameters;
10317 ----------------------------------
10318 -- Matching_Entry_Or_Subprogram --
10319 ----------------------------------
10321 function Matching_Entry_Or_Subprogram
10322 (Conc_Typ : Entity_Id;
10323 Subp : Entity_Id) return Entity_Id
10328 E := First_Entity (Conc_Typ);
10329 while Present (E) loop
10330 if Chars (Subp) = Chars (E)
10331 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10333 Check_Conforming_Parameters
10334 (First (Parameter_Specifications (Parent (E))),
10335 Next (First (Parameter_Specifications (Parent (Subp)))))
10344 end Matching_Entry_Or_Subprogram;
10346 -------------------------------------
10347 -- Matching_Dispatching_Subprogram --
10348 -------------------------------------
10350 function Matching_Dispatching_Subprogram
10351 (Conc_Typ : Entity_Id;
10352 Ent : Entity_Id) return Entity_Id
10357 -- Search for entities in the enclosing scope of this synchonized
10360 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10361 Push_Scope (Scope (Conc_Typ));
10362 E := Current_Entity_In_Scope (Ent);
10365 while Present (E) loop
10366 if Scope (E) = Scope (Conc_Typ)
10367 and then Comes_From_Source (E)
10368 and then Ekind (E) = E_Procedure
10369 and then Present (First_Entity (E))
10370 and then Is_Controlling_Formal (First_Entity (E))
10371 and then Etype (First_Entity (E)) = Conc_Typ
10373 Check_Conforming_Parameters
10374 (First (Parameter_Specifications (Parent (Ent))),
10375 Next (First (Parameter_Specifications (Parent (E)))))
10384 end Matching_Dispatching_Subprogram;
10386 --------------------------------------------
10387 -- Matching_Original_Protected_Subprogram --
10388 --------------------------------------------
10390 function Matching_Original_Protected_Subprogram
10391 (Prot_Typ : Entity_Id;
10392 Subp : Entity_Id) return Entity_Id
10394 ICF : constant Boolean :=
10395 Is_Controlling_Formal (First_Entity (Subp));
10399 -- Temporarily decorate the first parameter of Subp as controlling
10400 -- formal, required to invoke Subtype_Conformant.
10402 Set_Is_Controlling_Formal (First_Entity (Subp));
10405 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10407 while Present (E) loop
10408 if Scope (E) = Scope (Prot_Typ)
10409 and then Comes_From_Source (E)
10410 and then Ekind (Subp) = Ekind (E)
10411 and then Present (First_Entity (E))
10412 and then Is_Controlling_Formal (First_Entity (E))
10413 and then Etype (First_Entity (E)) = Prot_Typ
10414 and then Subtype_Conformant (Subp, E,
10415 Skip_Controlling_Formals => True)
10417 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10424 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10427 end Matching_Original_Protected_Subprogram;
10429 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10432 -- Case 1: E is a subprogram whose first formal is a concurrent type
10433 -- defined in the scope of E that has an entry or subprogram whose
10434 -- profile matches E.
10436 if Comes_From_Source (E)
10437 and then Is_Subprogram (E)
10438 and then Present (First_Entity (E))
10439 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10442 Scope (Corresponding_Concurrent_Type
10443 (Etype (First_Entity (E))))
10446 (Matching_Entry_Or_Subprogram
10447 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10450 Report_Conflict (E,
10451 Matching_Entry_Or_Subprogram
10452 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10457 -- Case 2: E is an internally built dispatching subprogram of a
10458 -- protected type and there is a subprogram defined in the enclosing
10459 -- scope of the protected type that has the original name of E and
10460 -- its profile is conformant with the profile of E. We check the
10461 -- name of the original protected subprogram associated with E since
10462 -- the expander builds dispatching primitives of protected functions
10463 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10465 elsif not Comes_From_Source (E)
10466 and then Is_Subprogram (E)
10467 and then Present (First_Entity (E))
10468 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10469 and then Present (Original_Protected_Subprogram (E))
10472 (Matching_Original_Protected_Subprogram
10473 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10476 Report_Conflict (E,
10477 Matching_Original_Protected_Subprogram
10478 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10482 -- Case 3: E is an entry of a synchronized type and a matching
10483 -- procedure has been previously defined in the enclosing scope
10484 -- of the synchronized type.
10486 elsif Comes_From_Source (E)
10487 and then Ekind (E) = E_Entry
10489 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10491 Report_Conflict (E,
10492 Matching_Dispatching_Subprogram (Current_Scope, E));
10497 end Has_Matching_Entry_Or_Subprogram;
10499 ----------------------------
10500 -- Is_Private_Declaration --
10501 ----------------------------
10503 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10504 Decl : constant Node_Id := Unit_Declaration_Node (E);
10505 Priv_Decls : List_Id;
10508 if Is_Package_Or_Generic_Package (Current_Scope)
10509 and then In_Private_Part (Current_Scope)
10512 Private_Declarations (Package_Specification (Current_Scope));
10514 return In_Package_Body (Current_Scope)
10516 (Is_List_Member (Decl)
10517 and then List_Containing (Decl) = Priv_Decls)
10518 or else (Nkind (Parent (Decl)) = N_Package_Specification
10520 Is_Compilation_Unit
10521 (Defining_Entity (Parent (Decl)))
10522 and then List_Containing (Parent (Parent (Decl))) =
10527 end Is_Private_Declaration;
10529 --------------------------
10530 -- Is_Overriding_Alias --
10531 --------------------------
10533 function Is_Overriding_Alias
10534 (Old_E : Entity_Id;
10535 New_E : Entity_Id) return Boolean
10537 AO : constant Entity_Id := Alias (Old_E);
10538 AN : constant Entity_Id := Alias (New_E);
10541 return Scope (AO) /= Scope (AN)
10542 or else No (DTC_Entity (AO))
10543 or else No (DTC_Entity (AN))
10544 or else DT_Position (AO) = DT_Position (AN);
10545 end Is_Overriding_Alias;
10547 ---------------------
10548 -- Report_Conflict --
10549 ---------------------
10551 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10553 Error_Msg_Sloc := Sloc (E);
10555 -- Generate message, with useful additional warning if in generic
10557 if Is_Generic_Unit (E) then
10558 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10559 Error_Msg_N ("\& conflicts with declaration#", S);
10561 Error_Msg_N ("& conflicts with declaration#", S);
10563 end Report_Conflict;
10565 -- Start of processing for New_Overloaded_Entity
10568 -- We need to look for an entity that S may override. This must be a
10569 -- homonym in the current scope, so we look for the first homonym of
10570 -- S in the current scope as the starting point for the search.
10572 E := Current_Entity_In_Scope (S);
10574 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10575 -- They are directly added to the list of primitive operations of
10576 -- Derived_Type, unless this is a rederivation in the private part
10577 -- of an operation that was already derived in the visible part of
10578 -- the current package.
10580 if Ada_Version >= Ada_2005
10581 and then Present (Derived_Type)
10582 and then Present (Alias (S))
10583 and then Is_Dispatching_Operation (Alias (S))
10584 and then Present (Find_Dispatching_Type (Alias (S)))
10585 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10587 -- For private types, when the full-view is processed we propagate to
10588 -- the full view the non-overridden entities whose attribute "alias"
10589 -- references an interface primitive. These entities were added by
10590 -- Derive_Subprograms to ensure that interface primitives are
10593 -- Inside_Freeze_Actions is non zero when S corresponds with an
10594 -- internal entity that links an interface primitive with its
10595 -- covering primitive through attribute Interface_Alias (see
10596 -- Add_Internal_Interface_Entities).
10598 if Inside_Freezing_Actions = 0
10599 and then Is_Package_Or_Generic_Package (Current_Scope)
10600 and then In_Private_Part (Current_Scope)
10601 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10602 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10603 and then Full_View (Defining_Identifier (Parent (E)))
10604 = Defining_Identifier (Parent (S))
10605 and then Alias (E) = Alias (S)
10607 Check_Operation_From_Private_View (S, E);
10608 Set_Is_Dispatching_Operation (S);
10613 Enter_Overloaded_Entity (S);
10614 Check_Dispatching_Operation (S, Empty);
10615 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10621 -- For synchronized types check conflicts of this entity with previously
10622 -- defined entities.
10624 if Ada_Version >= Ada_2005
10625 and then Has_Matching_Entry_Or_Subprogram (S)
10630 -- If there is no homonym then this is definitely not overriding
10633 Enter_Overloaded_Entity (S);
10634 Check_Dispatching_Operation (S, Empty);
10635 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10637 -- If subprogram has an explicit declaration, check whether it has an
10638 -- overriding indicator.
10640 if Comes_From_Source (S) then
10641 Check_Synchronized_Overriding (S, Overridden_Subp);
10643 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10644 -- it may have overridden some hidden inherited primitive. Update
10645 -- Overridden_Subp to avoid spurious errors when checking the
10646 -- overriding indicator.
10648 if Ada_Version >= Ada_2012
10649 and then No (Overridden_Subp)
10650 and then Is_Dispatching_Operation (S)
10651 and then Present (Overridden_Operation (S))
10653 Overridden_Subp := Overridden_Operation (S);
10656 Check_Overriding_Indicator
10657 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10659 -- The Ghost policy in effect at the point of declaration of a
10660 -- parent subprogram and an overriding subprogram must match
10661 -- (SPARK RM 6.9(17)).
10663 Check_Ghost_Overriding (S, Overridden_Subp);
10666 -- If there is a homonym that is not overloadable, then we have an
10667 -- error, except for the special cases checked explicitly below.
10669 elsif not Is_Overloadable (E) then
10671 -- Check for spurious conflict produced by a subprogram that has the
10672 -- same name as that of the enclosing generic package. The conflict
10673 -- occurs within an instance, between the subprogram and the renaming
10674 -- declaration for the package. After the subprogram, the package
10675 -- renaming declaration becomes hidden.
10677 if Ekind (E) = E_Package
10678 and then Present (Renamed_Object (E))
10679 and then Renamed_Object (E) = Current_Scope
10680 and then Nkind (Parent (Renamed_Object (E))) =
10681 N_Package_Specification
10682 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10685 Set_Is_Immediately_Visible (E, False);
10686 Enter_Overloaded_Entity (S);
10687 Set_Homonym (S, Homonym (E));
10688 Check_Dispatching_Operation (S, Empty);
10689 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10691 -- If the subprogram is implicit it is hidden by the previous
10692 -- declaration. However if it is dispatching, it must appear in the
10693 -- dispatch table anyway, because it can be dispatched to even if it
10694 -- cannot be called directly.
10696 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10697 Set_Scope (S, Current_Scope);
10699 if Is_Dispatching_Operation (Alias (S)) then
10700 Check_Dispatching_Operation (S, Empty);
10706 Report_Conflict (S, E);
10710 -- E exists and is overloadable
10713 Check_Synchronized_Overriding (S, Overridden_Subp);
10715 -- Loop through E and its homonyms to determine if any of them is
10716 -- the candidate for overriding by S.
10718 while Present (E) loop
10720 -- Definitely not interesting if not in the current scope
10722 if Scope (E) /= Current_Scope then
10725 -- A function can overload the name of an abstract state. The
10726 -- state can be viewed as a function with a profile that cannot
10727 -- be matched by anything.
10729 elsif Ekind (S) = E_Function
10730 and then Ekind (E) = E_Abstract_State
10732 Enter_Overloaded_Entity (S);
10735 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10736 -- procedures locate the internally generated spec. We enforce
10737 -- mode conformance since a tagged type may inherit from
10738 -- interfaces several null primitives which differ only in
10739 -- the mode of the formals.
10741 elsif not Comes_From_Source (S)
10742 and then Is_Null_Procedure (S)
10743 and then not Mode_Conformant (E, S)
10747 -- Check if we have type conformance
10749 elsif Type_Conformant (E, S) then
10751 -- If the old and new entities have the same profile and one
10752 -- is not the body of the other, then this is an error, unless
10753 -- one of them is implicitly declared.
10755 -- There are some cases when both can be implicit, for example
10756 -- when both a literal and a function that overrides it are
10757 -- inherited in a derivation, or when an inherited operation
10758 -- of a tagged full type overrides the inherited operation of
10759 -- a private extension. Ada 83 had a special rule for the
10760 -- literal case. In Ada 95, the later implicit operation hides
10761 -- the former, and the literal is always the former. In the
10762 -- odd case where both are derived operations declared at the
10763 -- same point, both operations should be declared, and in that
10764 -- case we bypass the following test and proceed to the next
10765 -- part. This can only occur for certain obscure cases in
10766 -- instances, when an operation on a type derived from a formal
10767 -- private type does not override a homograph inherited from
10768 -- the actual. In subsequent derivations of such a type, the
10769 -- DT positions of these operations remain distinct, if they
10772 if Present (Alias (S))
10773 and then (No (Alias (E))
10774 or else Comes_From_Source (E)
10775 or else Is_Abstract_Subprogram (S)
10777 (Is_Dispatching_Operation (E)
10778 and then Is_Overriding_Alias (E, S)))
10779 and then Ekind (E) /= E_Enumeration_Literal
10781 -- When an derived operation is overloaded it may be due to
10782 -- the fact that the full view of a private extension
10783 -- re-inherits. It has to be dealt with.
10785 if Is_Package_Or_Generic_Package (Current_Scope)
10786 and then In_Private_Part (Current_Scope)
10788 Check_Operation_From_Private_View (S, E);
10791 -- In any case the implicit operation remains hidden by the
10792 -- existing declaration, which is overriding. Indicate that
10793 -- E overrides the operation from which S is inherited.
10795 if Present (Alias (S)) then
10796 Set_Overridden_Operation (E, Alias (S));
10797 Inherit_Subprogram_Contract (E, Alias (S));
10800 Set_Overridden_Operation (E, S);
10801 Inherit_Subprogram_Contract (E, S);
10804 if Comes_From_Source (E) then
10805 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10807 -- The Ghost policy in effect at the point of declaration
10808 -- of a parent subprogram and an overriding subprogram
10809 -- must match (SPARK RM 6.9(17)).
10811 Check_Ghost_Overriding (E, S);
10816 -- Within an instance, the renaming declarations for actual
10817 -- subprograms may become ambiguous, but they do not hide each
10820 elsif Ekind (E) /= E_Entry
10821 and then not Comes_From_Source (E)
10822 and then not Is_Generic_Instance (E)
10823 and then (Present (Alias (E))
10824 or else Is_Intrinsic_Subprogram (E))
10825 and then (not In_Instance
10826 or else No (Parent (E))
10827 or else Nkind (Unit_Declaration_Node (E)) /=
10828 N_Subprogram_Renaming_Declaration)
10830 -- A subprogram child unit is not allowed to override an
10831 -- inherited subprogram (10.1.1(20)).
10833 if Is_Child_Unit (S) then
10835 ("child unit overrides inherited subprogram in parent",
10840 if Is_Non_Overriding_Operation (E, S) then
10841 Enter_Overloaded_Entity (S);
10843 if No (Derived_Type)
10844 or else Is_Tagged_Type (Derived_Type)
10846 Check_Dispatching_Operation (S, Empty);
10852 -- E is a derived operation or an internal operator which
10853 -- is being overridden. Remove E from further visibility.
10854 -- Furthermore, if E is a dispatching operation, it must be
10855 -- replaced in the list of primitive operations of its type
10856 -- (see Override_Dispatching_Operation).
10858 Overridden_Subp := E;
10864 Prev := First_Entity (Current_Scope);
10865 while Present (Prev) and then Next_Entity (Prev) /= E loop
10866 Next_Entity (Prev);
10869 -- It is possible for E to be in the current scope and
10870 -- yet not in the entity chain. This can only occur in a
10871 -- generic context where E is an implicit concatenation
10872 -- in the formal part, because in a generic body the
10873 -- entity chain starts with the formals.
10875 -- In GNATprove mode, a wrapper for an operation with
10876 -- axiomatization may be a homonym of another declaration
10877 -- for an actual subprogram (needs refinement ???).
10881 and then GNATprove_Mode
10883 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10884 N_Subprogram_Renaming_Declaration
10888 pragma Assert (Chars (E) = Name_Op_Concat);
10893 -- E must be removed both from the entity_list of the
10894 -- current scope, and from the visibility chain.
10896 if Debug_Flag_E then
10897 Write_Str ("Override implicit operation ");
10898 Write_Int (Int (E));
10902 -- If E is a predefined concatenation, it stands for four
10903 -- different operations. As a result, a single explicit
10904 -- declaration does not hide it. In a possible ambiguous
10905 -- situation, Disambiguate chooses the user-defined op,
10906 -- so it is correct to retain the previous internal one.
10908 if Chars (E) /= Name_Op_Concat
10909 or else Ekind (E) /= E_Operator
10911 -- For nondispatching derived operations that are
10912 -- overridden by a subprogram declared in the private
10913 -- part of a package, we retain the derived subprogram
10914 -- but mark it as not immediately visible. If the
10915 -- derived operation was declared in the visible part
10916 -- then this ensures that it will still be visible
10917 -- outside the package with the proper signature
10918 -- (calls from outside must also be directed to this
10919 -- version rather than the overriding one, unlike the
10920 -- dispatching case). Calls from inside the package
10921 -- will still resolve to the overriding subprogram
10922 -- since the derived one is marked as not visible
10923 -- within the package.
10925 -- If the private operation is dispatching, we achieve
10926 -- the overriding by keeping the implicit operation
10927 -- but setting its alias to be the overriding one. In
10928 -- this fashion the proper body is executed in all
10929 -- cases, but the original signature is used outside
10932 -- If the overriding is not in the private part, we
10933 -- remove the implicit operation altogether.
10935 if Is_Private_Declaration (S) then
10936 if not Is_Dispatching_Operation (E) then
10937 Set_Is_Immediately_Visible (E, False);
10939 -- Work done in Override_Dispatching_Operation,
10940 -- so nothing else needs to be done here.
10946 -- Find predecessor of E in Homonym chain
10948 if E = Current_Entity (E) then
10951 Prev_Vis := Current_Entity (E);
10952 while Homonym (Prev_Vis) /= E loop
10953 Prev_Vis := Homonym (Prev_Vis);
10957 if Prev_Vis /= Empty then
10959 -- Skip E in the visibility chain
10961 Set_Homonym (Prev_Vis, Homonym (E));
10964 Set_Name_Entity_Id (Chars (E), Homonym (E));
10967 Set_Next_Entity (Prev, Next_Entity (E));
10969 if No (Next_Entity (Prev)) then
10970 Set_Last_Entity (Current_Scope, Prev);
10975 Enter_Overloaded_Entity (S);
10977 -- For entities generated by Derive_Subprograms the
10978 -- overridden operation is the inherited primitive
10979 -- (which is available through the attribute alias).
10981 if not (Comes_From_Source (E))
10982 and then Is_Dispatching_Operation (E)
10983 and then Find_Dispatching_Type (E) =
10984 Find_Dispatching_Type (S)
10985 and then Present (Alias (E))
10986 and then Comes_From_Source (Alias (E))
10988 Set_Overridden_Operation (S, Alias (E));
10989 Inherit_Subprogram_Contract (S, Alias (E));
10991 -- Normal case of setting entity as overridden
10993 -- Note: Static_Initialization and Overridden_Operation
10994 -- attributes use the same field in subprogram entities.
10995 -- Static_Initialization is only defined for internal
10996 -- initialization procedures, where Overridden_Operation
10997 -- is irrelevant. Therefore the setting of this attribute
10998 -- must check whether the target is an init_proc.
11000 elsif not Is_Init_Proc (S) then
11001 Set_Overridden_Operation (S, E);
11002 Inherit_Subprogram_Contract (S, E);
11005 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11007 -- The Ghost policy in effect at the point of declaration
11008 -- of a parent subprogram and an overriding subprogram
11009 -- must match (SPARK RM 6.9(17)).
11011 Check_Ghost_Overriding (S, E);
11013 -- If S is a user-defined subprogram or a null procedure
11014 -- expanded to override an inherited null procedure, or a
11015 -- predefined dispatching primitive then indicate that E
11016 -- overrides the operation from which S is inherited.
11018 if Comes_From_Source (S)
11020 (Present (Parent (S))
11022 Nkind (Parent (S)) = N_Procedure_Specification
11024 Null_Present (Parent (S)))
11026 (Present (Alias (E))
11028 Is_Predefined_Dispatching_Operation (Alias (E)))
11030 if Present (Alias (E)) then
11031 Set_Overridden_Operation (S, Alias (E));
11032 Inherit_Subprogram_Contract (S, Alias (E));
11036 if Is_Dispatching_Operation (E) then
11038 -- An overriding dispatching subprogram inherits the
11039 -- convention of the overridden subprogram (AI-117).
11041 Set_Convention (S, Convention (E));
11042 Check_Dispatching_Operation (S, E);
11045 Check_Dispatching_Operation (S, Empty);
11048 Check_For_Primitive_Subprogram
11049 (Is_Primitive_Subp, Is_Overriding => True);
11050 goto Check_Inequality;
11053 -- Apparent redeclarations in instances can occur when two
11054 -- formal types get the same actual type. The subprograms in
11055 -- in the instance are legal, even if not callable from the
11056 -- outside. Calls from within are disambiguated elsewhere.
11057 -- For dispatching operations in the visible part, the usual
11058 -- rules apply, and operations with the same profile are not
11059 -- legal (B830001).
11061 elsif (In_Instance_Visible_Part
11062 and then not Is_Dispatching_Operation (E))
11063 or else In_Instance_Not_Visible
11067 -- Here we have a real error (identical profile)
11070 Error_Msg_Sloc := Sloc (E);
11072 -- Avoid cascaded errors if the entity appears in
11073 -- subsequent calls.
11075 Set_Scope (S, Current_Scope);
11077 -- Generate error, with extra useful warning for the case
11078 -- of a generic instance with no completion.
11080 if Is_Generic_Instance (S)
11081 and then not Has_Completion (E)
11084 ("instantiation cannot provide body for&", S);
11085 Error_Msg_N ("\& conflicts with declaration#", S);
11087 Error_Msg_N ("& conflicts with declaration#", S);
11094 -- If one subprogram has an access parameter and the other
11095 -- a parameter of an access type, calls to either might be
11096 -- ambiguous. Verify that parameters match except for the
11097 -- access parameter.
11099 if May_Hide_Profile then
11105 F1 := First_Formal (S);
11106 F2 := First_Formal (E);
11107 while Present (F1) and then Present (F2) loop
11108 if Is_Access_Type (Etype (F1)) then
11109 if not Is_Access_Type (Etype (F2))
11110 or else not Conforming_Types
11111 (Designated_Type (Etype (F1)),
11112 Designated_Type (Etype (F2)),
11115 May_Hide_Profile := False;
11119 not Conforming_Types
11120 (Etype (F1), Etype (F2), Type_Conformant)
11122 May_Hide_Profile := False;
11129 if May_Hide_Profile
11133 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11142 -- On exit, we know that S is a new entity
11144 Enter_Overloaded_Entity (S);
11145 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11146 Check_Overriding_Indicator
11147 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11149 -- The Ghost policy in effect at the point of declaration of a parent
11150 -- subprogram and an overriding subprogram must match
11151 -- (SPARK RM 6.9(17)).
11153 Check_Ghost_Overriding (S, Overridden_Subp);
11155 -- Overloading is not allowed in SPARK, except for operators
11157 if Nkind (S) /= N_Defining_Operator_Symbol then
11158 Error_Msg_Sloc := Sloc (Homonym (S));
11159 Check_SPARK_05_Restriction
11160 ("overloading not allowed with entity#", S);
11163 -- If S is a derived operation for an untagged type then by
11164 -- definition it's not a dispatching operation (even if the parent
11165 -- operation was dispatching), so Check_Dispatching_Operation is not
11166 -- called in that case.
11168 if No (Derived_Type)
11169 or else Is_Tagged_Type (Derived_Type)
11171 Check_Dispatching_Operation (S, Empty);
11175 -- If this is a user-defined equality operator that is not a derived
11176 -- subprogram, create the corresponding inequality. If the operation is
11177 -- dispatching, the expansion is done elsewhere, and we do not create
11178 -- an explicit inequality operation.
11180 <<Check_Inequality>>
11181 if Chars (S) = Name_Op_Eq
11182 and then Etype (S) = Standard_Boolean
11183 and then Present (Parent (S))
11184 and then not Is_Dispatching_Operation (S)
11186 Make_Inequality_Operator (S);
11187 Check_Untagged_Equality (S);
11189 end New_Overloaded_Entity;
11191 ---------------------
11192 -- Process_Formals --
11193 ---------------------
11195 procedure Process_Formals
11197 Related_Nod : Node_Id)
11199 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11200 -- Determine whether an access type designates a type coming from a
11203 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11204 -- Check whether the default has a class-wide type. After analysis the
11205 -- default has the type of the formal, so we must also check explicitly
11206 -- for an access attribute.
11208 ----------------------------------
11209 -- Designates_From_Limited_With --
11210 ----------------------------------
11212 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11213 Desig : Entity_Id := Typ;
11216 if Is_Access_Type (Desig) then
11217 Desig := Directly_Designated_Type (Desig);
11220 if Is_Class_Wide_Type (Desig) then
11221 Desig := Root_Type (Desig);
11225 Ekind (Desig) = E_Incomplete_Type
11226 and then From_Limited_With (Desig);
11227 end Designates_From_Limited_With;
11229 ---------------------------
11230 -- Is_Class_Wide_Default --
11231 ---------------------------
11233 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11235 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11236 or else (Nkind (D) = N_Attribute_Reference
11237 and then Attribute_Name (D) = Name_Access
11238 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11239 end Is_Class_Wide_Default;
11243 Context : constant Node_Id := Parent (Parent (T));
11245 Formal : Entity_Id;
11246 Formal_Type : Entity_Id;
11247 Param_Spec : Node_Id;
11250 Num_Out_Params : Nat := 0;
11251 First_Out_Param : Entity_Id := Empty;
11252 -- Used for setting Is_Only_Out_Parameter
11254 -- Start of processing for Process_Formals
11257 -- In order to prevent premature use of the formals in the same formal
11258 -- part, the Ekind is left undefined until all default expressions are
11259 -- analyzed. The Ekind is established in a separate loop at the end.
11261 Param_Spec := First (T);
11262 while Present (Param_Spec) loop
11263 Formal := Defining_Identifier (Param_Spec);
11264 Set_Never_Set_In_Source (Formal, True);
11265 Enter_Name (Formal);
11267 -- Case of ordinary parameters
11269 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11270 Find_Type (Parameter_Type (Param_Spec));
11271 Ptype := Parameter_Type (Param_Spec);
11273 if Ptype = Error then
11277 Formal_Type := Entity (Ptype);
11279 if Is_Incomplete_Type (Formal_Type)
11281 (Is_Class_Wide_Type (Formal_Type)
11282 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11284 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11285 -- primitive operations, as long as their completion is
11286 -- in the same declarative part. If in the private part
11287 -- this means that the type cannot be a Taft-amendment type.
11288 -- Check is done on package exit. For access to subprograms,
11289 -- the use is legal for Taft-amendment types.
11291 -- Ada 2012: tagged incomplete types are allowed as generic
11292 -- formal types. They do not introduce dependencies and the
11293 -- corresponding generic subprogram does not have a delayed
11294 -- freeze, because it does not need a freeze node. However,
11295 -- it is still the case that untagged incomplete types cannot
11296 -- be Taft-amendment types and must be completed in private
11297 -- part, so the subprogram must appear in the list of private
11298 -- dependents of the type.
11300 if Is_Tagged_Type (Formal_Type)
11301 or else (Ada_Version >= Ada_2012
11302 and then not From_Limited_With (Formal_Type)
11303 and then not Is_Generic_Type (Formal_Type))
11305 if Ekind (Scope (Current_Scope)) = E_Package
11306 and then not Is_Generic_Type (Formal_Type)
11307 and then not Is_Class_Wide_Type (Formal_Type)
11310 (Parent (T), N_Access_Function_Definition,
11311 N_Access_Procedure_Definition)
11313 Append_Elmt (Current_Scope,
11314 Private_Dependents (Base_Type (Formal_Type)));
11316 -- Freezing is delayed to ensure that Register_Prim
11317 -- will get called for this operation, which is needed
11318 -- in cases where static dispatch tables aren't built.
11319 -- (Note that the same is done for controlling access
11320 -- parameter cases in function Access_Definition.)
11322 if not Is_Thunk (Current_Scope) then
11323 Set_Has_Delayed_Freeze (Current_Scope);
11328 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11329 N_Access_Procedure_Definition)
11331 -- AI05-0151: Tagged incomplete types are allowed in all
11332 -- formal parts. Untagged incomplete types are not allowed
11333 -- in bodies. Limited views of either kind are not allowed
11334 -- if there is no place at which the non-limited view can
11335 -- become available.
11337 -- Incomplete formal untagged types are not allowed in
11338 -- subprogram bodies (but are legal in their declarations).
11339 -- This excludes bodies created for null procedures, which
11340 -- are basic declarations.
11342 if Is_Generic_Type (Formal_Type)
11343 and then not Is_Tagged_Type (Formal_Type)
11344 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11347 ("invalid use of formal incomplete type", Param_Spec);
11349 elsif Ada_Version >= Ada_2012 then
11350 if Is_Tagged_Type (Formal_Type)
11351 and then (not From_Limited_With (Formal_Type)
11352 or else not In_Package_Body)
11356 elsif Nkind_In (Context, N_Accept_Statement,
11357 N_Accept_Alternative,
11359 or else (Nkind (Context) = N_Subprogram_Body
11360 and then Comes_From_Source (Context))
11363 ("invalid use of untagged incomplete type &",
11364 Ptype, Formal_Type);
11369 ("invalid use of incomplete type&",
11370 Param_Spec, Formal_Type);
11372 -- Further checks on the legality of incomplete types
11373 -- in formal parts are delayed until the freeze point
11374 -- of the enclosing subprogram or access to subprogram.
11378 elsif Ekind (Formal_Type) = E_Void then
11380 ("premature use of&",
11381 Parameter_Type (Param_Spec), Formal_Type);
11384 -- Ada 2012 (AI-142): Handle aliased parameters
11386 if Ada_Version >= Ada_2012
11387 and then Aliased_Present (Param_Spec)
11389 Set_Is_Aliased (Formal);
11392 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11393 -- declaration corresponding to the null-excluding type of the
11394 -- formal in the enclosing scope. Finally, replace the parameter
11395 -- type of the formal with the internal subtype.
11397 if Ada_Version >= Ada_2005
11398 and then Null_Exclusion_Present (Param_Spec)
11400 if not Is_Access_Type (Formal_Type) then
11402 ("`NOT NULL` allowed only for an access type", Param_Spec);
11405 if Can_Never_Be_Null (Formal_Type)
11406 and then Comes_From_Source (Related_Nod)
11409 ("`NOT NULL` not allowed (& already excludes null)",
11410 Param_Spec, Formal_Type);
11414 Create_Null_Excluding_Itype
11416 Related_Nod => Related_Nod,
11417 Scope_Id => Scope (Current_Scope));
11419 -- If the designated type of the itype is an itype that is
11420 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11421 -- on the access subtype, to prevent order-of-elaboration
11422 -- issues in the backend.
11425 -- type T is access procedure;
11426 -- procedure Op (O : not null T);
11428 if Is_Itype (Directly_Designated_Type (Formal_Type))
11430 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11432 Set_Has_Delayed_Freeze (Formal_Type);
11437 -- An access formal type
11441 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11443 -- No need to continue if we already notified errors
11445 if not Present (Formal_Type) then
11449 -- Ada 2005 (AI-254)
11452 AD : constant Node_Id :=
11453 Access_To_Subprogram_Definition
11454 (Parameter_Type (Param_Spec));
11456 if Present (AD) and then Protected_Present (AD) then
11458 Replace_Anonymous_Access_To_Protected_Subprogram
11464 Set_Etype (Formal, Formal_Type);
11466 -- Deal with default expression if present
11468 Default := Expression (Param_Spec);
11470 if Present (Default) then
11471 Check_SPARK_05_Restriction
11472 ("default expression is not allowed", Default);
11474 if Out_Present (Param_Spec) then
11476 ("default initialization only allowed for IN parameters",
11480 -- Do the special preanalysis of the expression (see section on
11481 -- "Handling of Default Expressions" in the spec of package Sem).
11483 Preanalyze_Spec_Expression (Default, Formal_Type);
11485 -- An access to constant cannot be the default for
11486 -- an access parameter that is an access to variable.
11488 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11489 and then not Is_Access_Constant (Formal_Type)
11490 and then Is_Access_Type (Etype (Default))
11491 and then Is_Access_Constant (Etype (Default))
11494 ("formal that is access to variable cannot be initialized "
11495 & "with an access-to-constant expression", Default);
11498 -- Check that the designated type of an access parameter's default
11499 -- is not a class-wide type unless the parameter's designated type
11500 -- is also class-wide.
11502 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11503 and then not Designates_From_Limited_With (Formal_Type)
11504 and then Is_Class_Wide_Default (Default)
11505 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11508 ("access to class-wide expression not allowed here", Default);
11511 -- Check incorrect use of dynamically tagged expressions
11513 if Is_Tagged_Type (Formal_Type) then
11514 Check_Dynamically_Tagged_Expression
11516 Typ => Formal_Type,
11517 Related_Nod => Default);
11521 -- Ada 2005 (AI-231): Static checks
11523 if Ada_Version >= Ada_2005
11524 and then Is_Access_Type (Etype (Formal))
11525 and then Can_Never_Be_Null (Etype (Formal))
11527 Null_Exclusion_Static_Checks (Param_Spec);
11530 -- The following checks are relevant only when SPARK_Mode is on as
11531 -- these are not standard Ada legality rules.
11533 if SPARK_Mode = On then
11534 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11536 -- A function cannot have a parameter of mode IN OUT or OUT
11539 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11541 ("function cannot have parameter of mode `OUT` or "
11542 & "`IN OUT`", Formal);
11545 -- A procedure cannot have an effectively volatile formal
11546 -- parameter of mode IN because it behaves as a constant
11547 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11549 elsif Ekind (Scope (Formal)) = E_Procedure
11550 and then Ekind (Formal) = E_In_Parameter
11551 and then Is_Effectively_Volatile (Formal)
11554 ("formal parameter of mode `IN` cannot be volatile", Formal);
11562 -- If this is the formal part of a function specification, analyze the
11563 -- subtype mark in the context where the formals are visible but not
11564 -- yet usable, and may hide outer homographs.
11566 if Nkind (Related_Nod) = N_Function_Specification then
11567 Analyze_Return_Type (Related_Nod);
11570 -- Now set the kind (mode) of each formal
11572 Param_Spec := First (T);
11573 while Present (Param_Spec) loop
11574 Formal := Defining_Identifier (Param_Spec);
11575 Set_Formal_Mode (Formal);
11577 if Ekind (Formal) = E_In_Parameter then
11578 Set_Default_Value (Formal, Expression (Param_Spec));
11580 if Present (Expression (Param_Spec)) then
11581 Default := Expression (Param_Spec);
11583 if Is_Scalar_Type (Etype (Default)) then
11584 if Nkind (Parameter_Type (Param_Spec)) /=
11585 N_Access_Definition
11587 Formal_Type := Entity (Parameter_Type (Param_Spec));
11591 (Related_Nod, Parameter_Type (Param_Spec));
11594 Apply_Scalar_Range_Check (Default, Formal_Type);
11598 elsif Ekind (Formal) = E_Out_Parameter then
11599 Num_Out_Params := Num_Out_Params + 1;
11601 if Num_Out_Params = 1 then
11602 First_Out_Param := Formal;
11605 elsif Ekind (Formal) = E_In_Out_Parameter then
11606 Num_Out_Params := Num_Out_Params + 1;
11609 -- Skip remaining processing if formal type was in error
11611 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11612 goto Next_Parameter;
11615 -- Force call by reference if aliased
11618 Conv : constant Convention_Id := Convention (Etype (Formal));
11620 if Is_Aliased (Formal) then
11621 Set_Mechanism (Formal, By_Reference);
11623 -- Warn if user asked this to be passed by copy
11625 if Conv = Convention_Ada_Pass_By_Copy then
11627 ("cannot pass aliased parameter & by copy??", Formal);
11630 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11632 elsif Conv = Convention_Ada_Pass_By_Copy then
11633 Set_Mechanism (Formal, By_Copy);
11635 elsif Conv = Convention_Ada_Pass_By_Reference then
11636 Set_Mechanism (Formal, By_Reference);
11644 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11645 Set_Is_Only_Out_Parameter (First_Out_Param);
11647 end Process_Formals;
11649 ----------------------------
11650 -- Reference_Body_Formals --
11651 ----------------------------
11653 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11658 if Error_Posted (Spec) then
11662 -- Iterate over both lists. They may be of different lengths if the two
11663 -- specs are not conformant.
11665 Fs := First_Formal (Spec);
11666 Fb := First_Formal (Bod);
11667 while Present (Fs) and then Present (Fb) loop
11668 Generate_Reference (Fs, Fb, 'b');
11670 if Style_Check then
11671 Style.Check_Identifier (Fb, Fs);
11674 Set_Spec_Entity (Fb, Fs);
11675 Set_Referenced (Fs, False);
11679 end Reference_Body_Formals;
11681 -------------------------
11682 -- Set_Actual_Subtypes --
11683 -------------------------
11685 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11687 Formal : Entity_Id;
11689 First_Stmt : Node_Id := Empty;
11690 AS_Needed : Boolean;
11693 -- If this is an empty initialization procedure, no need to create
11694 -- actual subtypes (small optimization).
11696 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11699 -- Within a predicate function we do not want to generate local
11700 -- subtypes that may generate nested predicate functions.
11702 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11706 -- The subtype declarations may freeze the formals. The body generated
11707 -- for an expression function is not a freeze point, so do not emit
11708 -- these declarations (small loss of efficiency in rare cases).
11710 if Nkind (N) = N_Subprogram_Body
11711 and then Was_Expression_Function (N)
11716 Formal := First_Formal (Subp);
11717 while Present (Formal) loop
11718 T := Etype (Formal);
11720 -- We never need an actual subtype for a constrained formal
11722 if Is_Constrained (T) then
11723 AS_Needed := False;
11725 -- If we have unknown discriminants, then we do not need an actual
11726 -- subtype, or more accurately we cannot figure it out. Note that
11727 -- all class-wide types have unknown discriminants.
11729 elsif Has_Unknown_Discriminants (T) then
11730 AS_Needed := False;
11732 -- At this stage we have an unconstrained type that may need an
11733 -- actual subtype. For sure the actual subtype is needed if we have
11734 -- an unconstrained array type. However, in an instance, the type
11735 -- may appear as a subtype of the full view, while the actual is
11736 -- in fact private (in which case no actual subtype is needed) so
11737 -- check the kind of the base type.
11739 elsif Is_Array_Type (Base_Type (T)) then
11742 -- The only other case needing an actual subtype is an unconstrained
11743 -- record type which is an IN parameter (we cannot generate actual
11744 -- subtypes for the OUT or IN OUT case, since an assignment can
11745 -- change the discriminant values. However we exclude the case of
11746 -- initialization procedures, since discriminants are handled very
11747 -- specially in this context, see the section entitled "Handling of
11748 -- Discriminants" in Einfo.
11750 -- We also exclude the case of Discrim_SO_Functions (functions used
11751 -- in front-end layout mode for size/offset values), since in such
11752 -- functions only discriminants are referenced, and not only are such
11753 -- subtypes not needed, but they cannot always be generated, because
11754 -- of order of elaboration issues.
11756 elsif Is_Record_Type (T)
11757 and then Ekind (Formal) = E_In_Parameter
11758 and then Chars (Formal) /= Name_uInit
11759 and then not Is_Unchecked_Union (T)
11760 and then not Is_Discrim_SO_Function (Subp)
11764 -- All other cases do not need an actual subtype
11767 AS_Needed := False;
11770 -- Generate actual subtypes for unconstrained arrays and
11771 -- unconstrained discriminated records.
11774 if Nkind (N) = N_Accept_Statement then
11776 -- If expansion is active, the formal is replaced by a local
11777 -- variable that renames the corresponding entry of the
11778 -- parameter block, and it is this local variable that may
11779 -- require an actual subtype.
11781 if Expander_Active then
11782 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11784 Decl := Build_Actual_Subtype (T, Formal);
11787 if Present (Handled_Statement_Sequence (N)) then
11789 First (Statements (Handled_Statement_Sequence (N)));
11790 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11791 Mark_Rewrite_Insertion (Decl);
11793 -- If the accept statement has no body, there will be no
11794 -- reference to the actuals, so no need to compute actual
11801 Decl := Build_Actual_Subtype (T, Formal);
11802 Prepend (Decl, Declarations (N));
11803 Mark_Rewrite_Insertion (Decl);
11806 -- The declaration uses the bounds of an existing object, and
11807 -- therefore needs no constraint checks.
11809 Analyze (Decl, Suppress => All_Checks);
11810 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11812 -- We need to freeze manually the generated type when it is
11813 -- inserted anywhere else than in a declarative part.
11815 if Present (First_Stmt) then
11816 Insert_List_Before_And_Analyze (First_Stmt,
11817 Freeze_Entity (Defining_Identifier (Decl), N));
11819 -- Ditto if the type has a dynamic predicate, because the
11820 -- generated function will mention the actual subtype. The
11821 -- predicate may come from an explicit aspect of be inherited.
11823 elsif Has_Predicates (T) then
11824 Insert_List_Before_And_Analyze (Decl,
11825 Freeze_Entity (Defining_Identifier (Decl), N));
11828 if Nkind (N) = N_Accept_Statement
11829 and then Expander_Active
11831 Set_Actual_Subtype (Renamed_Object (Formal),
11832 Defining_Identifier (Decl));
11834 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11838 Next_Formal (Formal);
11840 end Set_Actual_Subtypes;
11842 ---------------------
11843 -- Set_Formal_Mode --
11844 ---------------------
11846 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11847 Spec : constant Node_Id := Parent (Formal_Id);
11848 Id : constant Entity_Id := Scope (Formal_Id);
11851 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11852 -- since we ensure that corresponding actuals are always valid at the
11853 -- point of the call.
11855 if Out_Present (Spec) then
11856 if Ekind_In (Id, E_Entry, E_Entry_Family)
11857 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11859 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11862 if Ekind_In (Id, E_Function, E_Generic_Function) then
11864 -- [IN] OUT parameters allowed for functions in Ada 2012
11866 if Ada_Version >= Ada_2012 then
11868 -- Even in Ada 2012 operators can only have IN parameters
11870 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11871 Error_Msg_N ("operators can only have IN parameters", Spec);
11874 if In_Present (Spec) then
11875 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11877 Set_Ekind (Formal_Id, E_Out_Parameter);
11880 -- But not in earlier versions of Ada
11883 Error_Msg_N ("functions can only have IN parameters", Spec);
11884 Set_Ekind (Formal_Id, E_In_Parameter);
11887 elsif In_Present (Spec) then
11888 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11891 Set_Ekind (Formal_Id, E_Out_Parameter);
11892 Set_Never_Set_In_Source (Formal_Id, True);
11893 Set_Is_True_Constant (Formal_Id, False);
11894 Set_Current_Value (Formal_Id, Empty);
11898 Set_Ekind (Formal_Id, E_In_Parameter);
11901 -- Set Is_Known_Non_Null for access parameters since the language
11902 -- guarantees that access parameters are always non-null. We also set
11903 -- Can_Never_Be_Null, since there is no way to change the value.
11905 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11907 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11908 -- null; In Ada 2005, only if then null_exclusion is explicit.
11910 if Ada_Version < Ada_2005
11911 or else Can_Never_Be_Null (Etype (Formal_Id))
11913 Set_Is_Known_Non_Null (Formal_Id);
11914 Set_Can_Never_Be_Null (Formal_Id);
11917 -- Ada 2005 (AI-231): Null-exclusion access subtype
11919 elsif Is_Access_Type (Etype (Formal_Id))
11920 and then Can_Never_Be_Null (Etype (Formal_Id))
11922 Set_Is_Known_Non_Null (Formal_Id);
11924 -- We can also set Can_Never_Be_Null (thus preventing some junk
11925 -- access checks) for the case of an IN parameter, which cannot
11926 -- be changed, or for an IN OUT parameter, which can be changed but
11927 -- not to a null value. But for an OUT parameter, the initial value
11928 -- passed in can be null, so we can't set this flag in that case.
11930 if Ekind (Formal_Id) /= E_Out_Parameter then
11931 Set_Can_Never_Be_Null (Formal_Id);
11935 Set_Mechanism (Formal_Id, Default_Mechanism);
11936 Set_Formal_Validity (Formal_Id);
11937 end Set_Formal_Mode;
11939 -------------------------
11940 -- Set_Formal_Validity --
11941 -------------------------
11943 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11945 -- If no validity checking, then we cannot assume anything about the
11946 -- validity of parameters, since we do not know there is any checking
11947 -- of the validity on the call side.
11949 if not Validity_Checks_On then
11952 -- If validity checking for parameters is enabled, this means we are
11953 -- not supposed to make any assumptions about argument values.
11955 elsif Validity_Check_Parameters then
11958 -- If we are checking in parameters, we will assume that the caller is
11959 -- also checking parameters, so we can assume the parameter is valid.
11961 elsif Ekind (Formal_Id) = E_In_Parameter
11962 and then Validity_Check_In_Params
11964 Set_Is_Known_Valid (Formal_Id, True);
11966 -- Similar treatment for IN OUT parameters
11968 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11969 and then Validity_Check_In_Out_Params
11971 Set_Is_Known_Valid (Formal_Id, True);
11973 end Set_Formal_Validity;
11975 ------------------------
11976 -- Subtype_Conformant --
11977 ------------------------
11979 function Subtype_Conformant
11980 (New_Id : Entity_Id;
11981 Old_Id : Entity_Id;
11982 Skip_Controlling_Formals : Boolean := False) return Boolean
11986 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
11987 Skip_Controlling_Formals => Skip_Controlling_Formals);
11989 end Subtype_Conformant;
11991 ---------------------
11992 -- Type_Conformant --
11993 ---------------------
11995 function Type_Conformant
11996 (New_Id : Entity_Id;
11997 Old_Id : Entity_Id;
11998 Skip_Controlling_Formals : Boolean := False) return Boolean
12002 May_Hide_Profile := False;
12004 (New_Id, Old_Id, Type_Conformant, False, Result,
12005 Skip_Controlling_Formals => Skip_Controlling_Formals);
12007 end Type_Conformant;
12009 -------------------------------
12010 -- Valid_Operator_Definition --
12011 -------------------------------
12013 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12016 Id : constant Name_Id := Chars (Designator);
12020 F := First_Formal (Designator);
12021 while Present (F) loop
12024 if Present (Default_Value (F)) then
12026 ("default values not allowed for operator parameters",
12029 -- For function instantiations that are operators, we must check
12030 -- separately that the corresponding generic only has in-parameters.
12031 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12032 -- an error could not arise in earlier versions of the language.
12034 elsif Ekind (F) /= E_In_Parameter then
12035 Error_Msg_N ("operators can only have IN parameters", F);
12041 -- Verify that user-defined operators have proper number of arguments
12042 -- First case of operators which can only be unary
12044 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12047 -- Case of operators which can be unary or binary
12049 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12050 N_OK := (N in 1 .. 2);
12052 -- All other operators can only be binary
12060 ("incorrect number of arguments for operator", Designator);
12064 and then Base_Type (Etype (Designator)) = Standard_Boolean
12065 and then not Is_Intrinsic_Subprogram (Designator)
12068 ("explicit definition of inequality not allowed", Designator);
12070 end Valid_Operator_Definition;