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;
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
3237 procedure Mask_Type (Typ : Entity_Id);
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);
3260 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3261 Mask_Type (Etype (Entity (Node)));
3263 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3264 Mask_Type (Scope (Entity (Node)));
3267 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3268 and then Present (Etype (Node))
3270 Mask_Type (Etype (Node));
3276 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3278 Return_Stmt : constant Node_Id :=
3279 First (Statements (Handled_Statement_Sequence (N)));
3281 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3283 Mask_References (Expression (Return_Stmt));
3286 end Mask_Unfrozen_Types;
3288 ---------------------------
3289 -- Restore_Limited_Views --
3290 ---------------------------
3292 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3293 Elmt : Elmt_Id := First_Elmt (Restore_List);
3297 while Present (Elmt) loop
3300 Set_Etype (Id, Node (Elmt));
3303 end Restore_Limited_Views;
3305 ----------------------------
3306 -- Set_Trivial_Subprogram --
3307 ----------------------------
3309 procedure Set_Trivial_Subprogram (N : Node_Id) is
3310 Nxt : constant Node_Id := Next (N);
3313 Set_Is_Trivial_Subprogram (Body_Id);
3315 if Present (Spec_Id) then
3316 Set_Is_Trivial_Subprogram (Spec_Id);
3320 and then Nkind (Nxt) = N_Simple_Return_Statement
3321 and then No (Next (Nxt))
3322 and then Present (Expression (Nxt))
3323 and then Is_Entity_Name (Expression (Nxt))
3325 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3327 end Set_Trivial_Subprogram;
3329 ---------------------------
3330 -- Unmask_Unfrozen_Types --
3331 ---------------------------
3333 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3334 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3337 while Present (Elmt) loop
3338 Set_Is_Frozen (Node (Elmt), False);
3341 end Unmask_Unfrozen_Types;
3343 ---------------------------------
3344 -- Verify_Overriding_Indicator --
3345 ---------------------------------
3347 procedure Verify_Overriding_Indicator is
3349 if Must_Override (Body_Spec) then
3350 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3351 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3355 elsif not Present (Overridden_Operation (Spec_Id)) then
3357 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3359 -- Overriding indicators aren't allowed for protected subprogram
3360 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3361 -- this to a warning if -gnatd.E is enabled.
3363 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3364 Error_Msg_Warn := Error_To_Warning;
3366 ("<<overriding indicator not allowed for protected "
3367 & "subprogram body", Body_Spec);
3370 elsif Must_Not_Override (Body_Spec) then
3371 if Present (Overridden_Operation (Spec_Id)) then
3373 ("subprogram& overrides inherited operation",
3374 Body_Spec, Spec_Id);
3376 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3377 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3380 ("subprogram& overrides predefined operator ",
3381 Body_Spec, Spec_Id);
3383 -- Overriding indicators aren't allowed for protected subprogram
3384 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3385 -- this to a warning if -gnatd.E is enabled.
3387 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3388 Error_Msg_Warn := Error_To_Warning;
3391 ("<<overriding indicator not allowed "
3392 & "for protected subprogram body", Body_Spec);
3394 -- If this is not a primitive operation, then the overriding
3395 -- indicator is altogether illegal.
3397 elsif not Is_Primitive (Spec_Id) then
3399 ("overriding indicator only allowed "
3400 & "if subprogram is primitive", Body_Spec);
3403 -- If checking the style rule and the operation overrides, then
3404 -- issue a warning about a missing overriding_indicator. Protected
3405 -- subprogram bodies are excluded from this style checking, since
3406 -- they aren't primitives (even though their declarations can
3407 -- override) and aren't allowed to have an overriding_indicator.
3410 and then Present (Overridden_Operation (Spec_Id))
3411 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3413 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3414 Style.Missing_Overriding (N, Body_Id);
3417 and then Can_Override_Operator (Spec_Id)
3418 and then not In_Predefined_Unit (Spec_Id)
3420 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3421 Style.Missing_Overriding (N, Body_Id);
3423 end Verify_Overriding_Indicator;
3427 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3428 Saved_ISMP : constant Boolean :=
3429 Ignore_SPARK_Mode_Pragmas_In_Instance;
3430 -- Save the Ghost and SPARK mode-related data to restore on exit
3432 -- Start of processing for Analyze_Subprogram_Body_Helper
3435 -- A [generic] subprogram body "freezes" the contract of the nearest
3436 -- enclosing package body and all other contracts encountered in the
3437 -- same declarative part up to and excluding the subprogram body:
3439 -- package body Nearest_Enclosing_Package
3440 -- with Refined_State => (State => Constit)
3444 -- procedure Freezes_Enclosing_Package_Body
3445 -- with Refined_Depends => (Input => Constit) ...
3447 -- This ensures that any annotations referenced by the contract of the
3448 -- [generic] subprogram body are available. This form of "freezing" is
3449 -- decoupled from the usual Freeze_xxx mechanism because it must also
3450 -- work in the context of generics where normal freezing is disabled.
3452 -- Only bodies coming from source should cause this type of "freezing".
3453 -- Expression functions that act as bodies and complete an initial
3454 -- declaration must be included in this category, hence the use of
3457 if Comes_From_Source (Original_Node (N)) then
3458 Analyze_Previous_Contracts (N);
3461 -- Generic subprograms are handled separately. They always have a
3462 -- generic specification. Determine whether current scope has a
3463 -- previous declaration.
3465 -- If the subprogram body is defined within an instance of the same
3466 -- name, the instance appears as a package renaming, and will be hidden
3467 -- within the subprogram.
3469 if Present (Prev_Id)
3470 and then not Is_Overloadable (Prev_Id)
3471 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3472 or else Comes_From_Source (Prev_Id))
3474 if Is_Generic_Subprogram (Prev_Id) then
3477 -- A subprogram body is Ghost when it is stand alone and subject
3478 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3479 -- the mode now to ensure that any nodes generated during analysis
3480 -- and expansion are properly marked as Ghost.
3482 Mark_And_Set_Ghost_Body (N, Spec_Id);
3484 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3485 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3487 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3489 if Nkind (N) = N_Subprogram_Body then
3490 HSS := Handled_Statement_Sequence (N);
3491 Check_Missing_Return;
3496 -- Otherwise a previous entity conflicts with the subprogram name.
3497 -- Attempting to enter name will post error.
3500 Enter_Name (Body_Id);
3504 -- Non-generic case, find the subprogram declaration, if one was seen,
3505 -- or enter new overloaded entity in the current scope. If the
3506 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3507 -- part of the context of one of its subunits. No need to redo the
3510 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3514 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3516 if Nkind (N) = N_Subprogram_Body_Stub
3517 or else No (Corresponding_Spec (N))
3519 if Is_Private_Concurrent_Primitive (Body_Id) then
3520 Spec_Id := Disambiguate_Spec;
3522 -- A subprogram body is Ghost when it is stand alone and
3523 -- subject to pragma Ghost or when the corresponding spec is
3524 -- Ghost. Set the mode now to ensure that any nodes generated
3525 -- during analysis and expansion are properly marked as Ghost.
3527 Mark_And_Set_Ghost_Body (N, Spec_Id);
3530 Spec_Id := Find_Corresponding_Spec (N);
3532 -- A subprogram body is Ghost when it is stand alone and
3533 -- subject to pragma Ghost or when the corresponding spec is
3534 -- Ghost. Set the mode now to ensure that any nodes generated
3535 -- during analysis and expansion are properly marked as Ghost.
3537 Mark_And_Set_Ghost_Body (N, Spec_Id);
3539 -- In GNATprove mode, if the body has no previous spec, create
3540 -- one so that the inlining machinery can operate properly.
3541 -- Transfer aspects, if any, to the new spec, so that they
3542 -- are legal and can be processed ahead of the body.
3543 -- We make two copies of the given spec, one for the new
3544 -- declaration, and one for the body.
3546 if No (Spec_Id) and then GNATprove_Mode
3548 -- Inlining does not apply during pre-analysis of code
3550 and then Full_Analysis
3552 -- Inlining only applies to full bodies, not stubs
3554 and then Nkind (N) /= N_Subprogram_Body_Stub
3556 -- Inlining only applies to bodies in the source code, not to
3557 -- those generated by the compiler. In particular, expression
3558 -- functions, whose body is generated by the compiler, are
3559 -- treated specially by GNATprove.
3561 and then Comes_From_Source (Body_Id)
3563 -- This cannot be done for a compilation unit, which is not
3564 -- in a context where we can insert a new spec.
3566 and then Is_List_Member (N)
3568 -- Inlining only applies to subprograms without contracts,
3569 -- as a contract is a sign that GNATprove should perform a
3570 -- modular analysis of the subprogram instead of a contextual
3571 -- analysis at each call site. The same test is performed in
3572 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3573 -- here in another form (because the contract has not been
3574 -- attached to the body) to avoid front-end errors in case
3575 -- pragmas are used instead of aspects, because the
3576 -- corresponding pragmas in the body would not be transferred
3577 -- to the spec, leading to legality errors.
3579 and then not Body_Has_Contract
3580 and then not Inside_A_Generic
3582 Build_Subprogram_Declaration;
3584 -- If this is a function that returns a constrained array, and
3585 -- we are generating SPARK_For_C, create subprogram declaration
3586 -- to simplify subsequent C generation.
3589 and then Modify_Tree_For_C
3590 and then Nkind (Body_Spec) = N_Function_Specification
3591 and then Is_Array_Type (Etype (Body_Id))
3592 and then Is_Constrained (Etype (Body_Id))
3594 Build_Subprogram_Declaration;
3598 -- If this is a duplicate body, no point in analyzing it
3600 if Error_Posted (N) then
3604 -- A subprogram body should cause freezing of its own declaration,
3605 -- but if there was no previous explicit declaration, then the
3606 -- subprogram will get frozen too late (there may be code within
3607 -- the body that depends on the subprogram having been frozen,
3608 -- such as uses of extra formals), so we force it to be frozen
3609 -- here. Same holds if the body and spec are compilation units.
3610 -- Finally, if the return type is an anonymous access to protected
3611 -- subprogram, it must be frozen before the body because its
3612 -- expansion has generated an equivalent type that is used when
3613 -- elaborating the body.
3615 -- An exception in the case of Ada 2012, AI05-177: The bodies
3616 -- created for expression functions do not freeze.
3619 and then Nkind (Original_Node (N)) /= N_Expression_Function
3621 Freeze_Before (N, Body_Id);
3623 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3624 Freeze_Before (N, Spec_Id);
3626 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3627 Freeze_Before (N, Etype (Body_Id));
3631 Spec_Id := Corresponding_Spec (N);
3633 -- A subprogram body is Ghost when it is stand alone and subject
3634 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3635 -- the mode now to ensure that any nodes generated during analysis
3636 -- and expansion are properly marked as Ghost.
3638 Mark_And_Set_Ghost_Body (N, Spec_Id);
3642 -- Previously we scanned the body to look for nested subprograms, and
3643 -- rejected an inline directive if nested subprograms were present,
3644 -- because the back-end would generate conflicting symbols for the
3645 -- nested bodies. This is now unnecessary.
3647 -- Look ahead to recognize a pragma Inline that appears after the body
3649 Check_Inline_Pragma (Spec_Id);
3651 -- Deal with special case of a fully private operation in the body of
3652 -- the protected type. We must create a declaration for the subprogram,
3653 -- in order to attach the protected subprogram that will be used in
3654 -- internal calls. We exclude compiler generated bodies from the
3655 -- expander since the issue does not arise for those cases.
3658 and then Comes_From_Source (N)
3659 and then Is_Protected_Type (Current_Scope)
3661 Spec_Id := Build_Private_Protected_Declaration (N);
3664 -- If we are generating C and this is a function returning a constrained
3665 -- array type for which we must create a procedure with an extra out
3666 -- parameter, build and analyze the body now. The procedure declaration
3667 -- has already been created. We reuse the source body of the function,
3668 -- because in an instance it may contain global references that cannot
3669 -- be reanalyzed. The source function itself is not used any further,
3670 -- so we mark it as having a completion. If the subprogram is a stub the
3671 -- transformation is done later, when the proper body is analyzed.
3674 and then Modify_Tree_For_C
3675 and then Present (Spec_Id)
3676 and then Ekind (Spec_Id) = E_Function
3677 and then Nkind (N) /= N_Subprogram_Body_Stub
3678 and then Rewritten_For_C (Spec_Id)
3680 Set_Has_Completion (Spec_Id);
3682 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3685 -- The entity for the created procedure must remain invisible, so it
3686 -- does not participate in resolution of subsequent references to the
3689 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3693 -- If a separate spec is present, then deal with freezing issues
3695 if Present (Spec_Id) then
3696 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3697 Verify_Overriding_Indicator;
3699 -- In general, the spec will be frozen when we start analyzing the
3700 -- body. However, for internally generated operations, such as
3701 -- wrapper functions for inherited operations with controlling
3702 -- results, the spec may not have been frozen by the time we expand
3703 -- the freeze actions that include the bodies. In particular, extra
3704 -- formals for accessibility or for return-in-place may need to be
3705 -- generated. Freeze nodes, if any, are inserted before the current
3706 -- body. These freeze actions are also needed in ASIS mode and in
3707 -- Compile_Only mode to enable the proper back-end type annotations.
3708 -- They are necessary in any case to insure order of elaboration
3711 if not Is_Frozen (Spec_Id)
3712 and then (Expander_Active
3714 or else (Operating_Mode = Check_Semantics
3715 and then Serious_Errors_Detected = 0))
3717 -- The body generated for an expression function that is not a
3718 -- completion is a freeze point neither for the profile nor for
3719 -- anything else. That's why, in order to prevent any freezing
3720 -- during analysis, we need to mask types declared outside the
3721 -- expression that are not yet frozen.
3723 if Nkind (N) = N_Subprogram_Body
3724 and then Was_Expression_Function (N)
3725 and then not Has_Completion (Spec_Id)
3727 Set_Is_Frozen (Spec_Id);
3728 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3730 Set_Has_Delayed_Freeze (Spec_Id);
3731 Freeze_Before (N, Spec_Id);
3736 -- If the subprogram has a class-wide clone, build its body as a copy
3737 -- of the original body, and rewrite body of original subprogram as a
3738 -- wrapper that calls the clone.
3740 if Present (Spec_Id)
3741 and then Present (Class_Wide_Clone (Spec_Id))
3742 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3744 Build_Class_Wide_Clone_Body (Spec_Id, N);
3746 -- This is the new body for the existing primitive operation
3748 Rewrite (N, Build_Class_Wide_Clone_Call
3749 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3750 Set_Has_Completion (Spec_Id, False);
3755 -- Place subprogram on scope stack, and make formals visible. If there
3756 -- is a spec, the visible entity remains that of the spec.
3758 if Present (Spec_Id) then
3759 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3761 if Is_Child_Unit (Spec_Id) then
3762 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3766 Style.Check_Identifier (Body_Id, Spec_Id);
3769 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3770 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3772 if Is_Abstract_Subprogram (Spec_Id) then
3773 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3777 Set_Convention (Body_Id, Convention (Spec_Id));
3778 Set_Has_Completion (Spec_Id);
3780 if Is_Protected_Type (Scope (Spec_Id)) then
3781 Prot_Typ := Scope (Spec_Id);
3784 -- If this is a body generated for a renaming, do not check for
3785 -- full conformance. The check is redundant, because the spec of
3786 -- the body is a copy of the spec in the renaming declaration,
3787 -- and the test can lead to spurious errors on nested defaults.
3789 if Present (Spec_Decl)
3790 and then not Comes_From_Source (N)
3792 (Nkind (Original_Node (Spec_Decl)) =
3793 N_Subprogram_Renaming_Declaration
3794 or else (Present (Corresponding_Body (Spec_Decl))
3796 Nkind (Unit_Declaration_Node
3797 (Corresponding_Body (Spec_Decl))) =
3798 N_Subprogram_Renaming_Declaration))
3802 -- Conversely, the spec may have been generated for specless body
3803 -- with an inline pragma. The entity comes from source, which is
3804 -- both semantically correct and necessary for proper inlining.
3805 -- The subprogram declaration itself is not in the source.
3807 elsif Comes_From_Source (N)
3808 and then Present (Spec_Decl)
3809 and then not Comes_From_Source (Spec_Decl)
3810 and then Has_Pragma_Inline (Spec_Id)
3817 Fully_Conformant, True, Conformant, Body_Id);
3820 -- If the body is not fully conformant, we have to decide if we
3821 -- should analyze it or not. If it has a really messed up profile
3822 -- then we probably should not analyze it, since we will get too
3823 -- many bogus messages.
3825 -- Our decision is to go ahead in the non-fully conformant case
3826 -- only if it is at least mode conformant with the spec. Note
3827 -- that the call to Check_Fully_Conformant has issued the proper
3828 -- error messages to complain about the lack of conformance.
3831 and then not Mode_Conformant (Body_Id, Spec_Id)
3837 if Spec_Id /= Body_Id then
3838 Reference_Body_Formals (Spec_Id, Body_Id);
3841 Set_Ekind (Body_Id, E_Subprogram_Body);
3843 if Nkind (N) = N_Subprogram_Body_Stub then
3844 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3849 Set_Corresponding_Spec (N, Spec_Id);
3851 -- Ada 2005 (AI-345): If the operation is a primitive operation
3852 -- of a concurrent type, the type of the first parameter has been
3853 -- replaced with the corresponding record, which is the proper
3854 -- run-time structure to use. However, within the body there may
3855 -- be uses of the formals that depend on primitive operations
3856 -- of the type (in particular calls in prefixed form) for which
3857 -- we need the original concurrent type. The operation may have
3858 -- several controlling formals, so the replacement must be done
3861 if Comes_From_Source (Spec_Id)
3862 and then Present (First_Entity (Spec_Id))
3863 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3864 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3865 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3866 and then Present (Corresponding_Concurrent_Type
3867 (Etype (First_Entity (Spec_Id))))
3870 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3874 Form := First_Formal (Spec_Id);
3875 while Present (Form) loop
3876 if Etype (Form) = Typ then
3877 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3885 -- Make the formals visible, and place subprogram on scope stack.
3886 -- This is also the point at which we set Last_Real_Spec_Entity
3887 -- to mark the entities which will not be moved to the body.
3889 Install_Formals (Spec_Id);
3890 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3892 -- Within an instance, add local renaming declarations so that
3893 -- gdb can retrieve the values of actuals more easily. This is
3894 -- only relevant if generating code (and indeed we definitely
3895 -- do not want these definitions -gnatc mode, because that would
3898 if Is_Generic_Instance (Spec_Id)
3899 and then Is_Wrapper_Package (Current_Scope)
3900 and then Expander_Active
3902 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3905 Push_Scope (Spec_Id);
3907 -- Make sure that the subprogram is immediately visible. For
3908 -- child units that have no separate spec this is indispensable.
3909 -- Otherwise it is safe albeit redundant.
3911 Set_Is_Immediately_Visible (Spec_Id);
3914 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3915 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3916 Set_Scope (Body_Id, Scope (Spec_Id));
3918 -- Case of subprogram body with no previous spec
3921 -- Check for style warning required
3925 -- Only apply check for source level subprograms for which checks
3926 -- have not been suppressed.
3928 and then Comes_From_Source (Body_Id)
3929 and then not Suppress_Style_Checks (Body_Id)
3931 -- No warnings within an instance
3933 and then not In_Instance
3935 -- No warnings for expression functions
3937 and then Nkind (Original_Node (N)) /= N_Expression_Function
3939 Style.Body_With_No_Spec (N);
3942 New_Overloaded_Entity (Body_Id);
3944 if Nkind (N) /= N_Subprogram_Body_Stub then
3945 Set_Acts_As_Spec (N);
3946 Generate_Definition (Body_Id);
3948 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3950 -- If the body is an entry wrapper created for an entry with
3951 -- preconditions, it must be compiled in the context of the
3952 -- enclosing synchronized object, because it may mention other
3953 -- operations of the type.
3955 if Is_Entry_Wrapper (Body_Id) then
3957 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3960 Install_Declarations (Prot);
3964 Install_Formals (Body_Id);
3966 Push_Scope (Body_Id);
3969 -- For stubs and bodies with no previous spec, generate references to
3972 Generate_Reference_To_Formals (Body_Id);
3975 -- Entry barrier functions are generated outside the protected type and
3976 -- should not carry the SPARK_Mode of the enclosing context.
3978 if Nkind (N) = N_Subprogram_Body
3979 and then Is_Entry_Barrier_Function (N)
3983 -- The body is generated as part of expression function expansion. When
3984 -- the expression function appears in the visible declarations of a
3985 -- package, the body is added to the private declarations. Since both
3986 -- declarative lists may be subject to a different SPARK_Mode, inherit
3987 -- the mode of the spec.
3989 -- package P with SPARK_Mode is
3990 -- function Expr_Func ... is (...); -- original
3991 -- [function Expr_Func ...;] -- generated spec
3994 -- pragma SPARK_Mode (Off);
3995 -- [function Expr_Func ... is return ...;] -- generated body
3996 -- end P; -- mode is ON
3998 elsif not Comes_From_Source (N)
3999 and then Present (Spec_Id)
4000 and then Is_Expression_Function (Spec_Id)
4002 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4003 Set_SPARK_Pragma_Inherited
4004 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4006 -- Set the SPARK_Mode from the current context (may be overwritten later
4007 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4008 -- initially on a stand-alone subprogram body, but is then relocated to
4009 -- a generated corresponding spec. In this scenario the mode is shared
4010 -- between the spec and body.
4012 elsif No (SPARK_Pragma (Body_Id)) then
4013 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4014 Set_SPARK_Pragma_Inherited (Body_Id);
4017 -- A subprogram body may be instantiated or inlined at a later pass.
4018 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4019 -- applied to the initial declaration of the body.
4021 if Present (Spec_Id) then
4022 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4023 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4027 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4028 -- case the body is instantiated or inlined later and out of context.
4029 -- The body uses this attribute to restore the value of the global
4032 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4033 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4035 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4036 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4040 -- If this is the proper body of a stub, we must verify that the stub
4041 -- conforms to the body, and to the previous spec if one was present.
4042 -- We know already that the body conforms to that spec. This test is
4043 -- only required for subprograms that come from source.
4045 if Nkind (Parent (N)) = N_Subunit
4046 and then Comes_From_Source (N)
4047 and then not Error_Posted (Body_Id)
4048 and then Nkind (Corresponding_Stub (Parent (N))) =
4049 N_Subprogram_Body_Stub
4052 Old_Id : constant Entity_Id :=
4054 (Specification (Corresponding_Stub (Parent (N))));
4056 Conformant : Boolean := False;
4059 if No (Spec_Id) then
4060 Check_Fully_Conformant (Body_Id, Old_Id);
4064 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4066 if not Conformant then
4068 -- The stub was taken to be a new declaration. Indicate that
4071 Set_Has_Completion (Old_Id, False);
4077 Set_Has_Completion (Body_Id);
4078 Check_Eliminated (Body_Id);
4080 -- Analyze any aspect specifications that appear on the subprogram body
4081 -- stub. Stop the analysis now as the stub does not have a declarative
4082 -- or a statement part, and it cannot be inlined.
4084 if Nkind (N) = N_Subprogram_Body_Stub then
4085 if Has_Aspects (N) then
4086 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4094 -- Note: Normally we don't do any inlining if expansion is off, since
4095 -- we won't generate code in any case. An exception arises in GNATprove
4096 -- mode where we want to expand some calls in place, even with expansion
4097 -- disabled, since the inlining eases formal verification.
4099 if not GNATprove_Mode
4100 and then Expander_Active
4101 and then Serious_Errors_Detected = 0
4102 and then Present (Spec_Id)
4103 and then Has_Pragma_Inline (Spec_Id)
4105 -- Legacy implementation (relying on front-end inlining)
4107 if not Back_End_Inlining then
4108 if (Has_Pragma_Inline_Always (Spec_Id)
4109 and then not Opt.Disable_FE_Inline_Always)
4110 or else (Front_End_Inlining
4111 and then not Opt.Disable_FE_Inline)
4113 Build_Body_To_Inline (N, Spec_Id);
4116 -- New implementation (relying on back-end inlining)
4119 if Has_Pragma_Inline_Always (Spec_Id)
4120 or else Optimization_Level > 0
4122 -- Handle function returning an unconstrained type
4124 if Comes_From_Source (Body_Id)
4125 and then Ekind (Spec_Id) = E_Function
4126 and then Returns_Unconstrained_Type (Spec_Id)
4128 -- If function builds in place, i.e. returns a limited type,
4129 -- inlining cannot be done.
4131 and then not Is_Limited_Type (Etype (Spec_Id))
4133 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4137 Subp_Body : constant Node_Id :=
4138 Unit_Declaration_Node (Body_Id);
4139 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4142 -- Do not pass inlining to the backend if the subprogram
4143 -- has declarations or statements which cannot be inlined
4144 -- by the backend. This check is done here to emit an
4145 -- error instead of the generic warning message reported
4146 -- by the GCC backend (ie. "function might not be
4149 if Present (Subp_Decl)
4150 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4154 elsif Has_Excluded_Statement
4157 (Handled_Statement_Sequence (Subp_Body)))
4161 -- If the backend inlining is available then at this
4162 -- stage we only have to mark the subprogram as inlined.
4163 -- The expander will take care of registering it in the
4164 -- table of subprograms inlined by the backend a part of
4165 -- processing calls to it (cf. Expand_Call)
4168 Set_Is_Inlined (Spec_Id);
4175 -- In GNATprove mode, inline only when there is a separate subprogram
4176 -- declaration for now, as inlining of subprogram bodies acting as
4177 -- declarations, or subprogram stubs, are not supported by front-end
4178 -- inlining. This inlining should occur after analysis of the body, so
4179 -- that it is known whether the value of SPARK_Mode, which can be
4180 -- defined by a pragma inside the body, is applicable to the body.
4181 -- Inlining can be disabled with switch -gnatdm
4183 elsif GNATprove_Mode
4184 and then Full_Analysis
4185 and then not Inside_A_Generic
4186 and then Present (Spec_Id)
4188 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4189 and then Body_Has_SPARK_Mode_On
4190 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4191 and then not Body_Has_Contract
4192 and then not Debug_Flag_M
4194 Build_Body_To_Inline (N, Spec_Id);
4197 -- When generating code, inherited pre/postconditions are handled when
4198 -- expanding the corresponding contract.
4200 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4201 -- of the specification we have to install the private withed units.
4202 -- This holds for child units as well.
4204 if Is_Compilation_Unit (Body_Id)
4205 or else Nkind (Parent (N)) = N_Compilation_Unit
4207 Install_Private_With_Clauses (Body_Id);
4210 Check_Anonymous_Return;
4212 -- Set the Protected_Formal field of each extra formal of the protected
4213 -- subprogram to reference the corresponding extra formal of the
4214 -- subprogram that implements it. For regular formals this occurs when
4215 -- the protected subprogram's declaration is expanded, but the extra
4216 -- formals don't get created until the subprogram is frozen. We need to
4217 -- do this before analyzing the protected subprogram's body so that any
4218 -- references to the original subprogram's extra formals will be changed
4219 -- refer to the implementing subprogram's formals (see Expand_Formal).
4221 if Present (Spec_Id)
4222 and then Is_Protected_Type (Scope (Spec_Id))
4223 and then Present (Protected_Body_Subprogram (Spec_Id))
4226 Impl_Subp : constant Entity_Id :=
4227 Protected_Body_Subprogram (Spec_Id);
4228 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4229 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4232 while Present (Prot_Ext_Formal) loop
4233 pragma Assert (Present (Impl_Ext_Formal));
4234 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4235 Next_Formal_With_Extras (Prot_Ext_Formal);
4236 Next_Formal_With_Extras (Impl_Ext_Formal);
4241 -- Now we can go on to analyze the body
4243 HSS := Handled_Statement_Sequence (N);
4244 Set_Actual_Subtypes (N, Current_Scope);
4246 -- Add a declaration for the Protection object, renaming declarations
4247 -- for discriminals and privals and finally a declaration for the entry
4248 -- family index (if applicable). This form of early expansion is done
4249 -- when the Expander is active because Install_Private_Data_Declarations
4250 -- references entities which were created during regular expansion. The
4251 -- subprogram entity must come from source, and not be an internally
4252 -- generated subprogram.
4255 and then Present (Prot_Typ)
4256 and then Present (Spec_Id)
4257 and then Comes_From_Source (Spec_Id)
4258 and then not Is_Eliminated (Spec_Id)
4260 Install_Private_Data_Declarations
4261 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4264 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4265 -- may now appear in parameter and result profiles. Since the analysis
4266 -- of a subprogram body may use the parameter and result profile of the
4267 -- spec, swap any limited views with their non-limited counterpart.
4269 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4270 Exch_Views := Exchange_Limited_Views (Spec_Id);
4273 -- If the return type is an anonymous access type whose designated type
4274 -- is the limited view of a class-wide type and the non-limited view is
4275 -- available, update the return type accordingly.
4277 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4283 Rtyp := Etype (Spec_Id);
4285 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4286 Etyp := Directly_Designated_Type (Rtyp);
4288 if Is_Class_Wide_Type (Etyp)
4289 and then From_Limited_With (Etyp)
4292 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4298 -- Analyze any aspect specifications that appear on the subprogram body
4300 if Has_Aspects (N) then
4301 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4304 Analyze_Declarations (Declarations (N));
4306 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4308 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4309 if Present (SPARK_Pragma (Spec_Id)) then
4310 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4312 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4314 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4315 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4316 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4318 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4321 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4325 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4326 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4327 Error_Msg_Sloc := Sloc (Spec_Id);
4329 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4333 -- A subprogram body "freezes" its own contract. Analyze the contract
4334 -- after the declarations of the body have been processed as pragmas
4335 -- are now chained on the contract of the subprogram body.
4337 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4339 -- Check completion, and analyze the statements
4342 Inspect_Deferred_Constant_Completion (Declarations (N));
4345 -- Deal with end of scope processing for the body
4347 Process_End_Label (HSS, 't', Current_Scope);
4350 -- If we are compiling an entry wrapper, remove the enclosing
4351 -- synchronized object from the stack.
4353 if Is_Entry_Wrapper (Body_Id) then
4357 Check_Subprogram_Order (N);
4358 Set_Analyzed (Body_Id);
4360 -- If we have a separate spec, then the analysis of the declarations
4361 -- caused the entities in the body to be chained to the spec id, but
4362 -- we want them chained to the body id. Only the formal parameters
4363 -- end up chained to the spec id in this case.
4365 if Present (Spec_Id) then
4367 -- We must conform to the categorization of our spec
4369 Validate_Categorization_Dependency (N, Spec_Id);
4371 -- And if this is a child unit, the parent units must conform
4373 if Is_Child_Unit (Spec_Id) then
4374 Validate_Categorization_Dependency
4375 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4378 -- Here is where we move entities from the spec to the body
4380 -- Case where there are entities that stay with the spec
4382 if Present (Last_Real_Spec_Entity) then
4384 -- No body entities (happens when the only real spec entities come
4385 -- from precondition and postcondition pragmas).
4387 if No (Last_Entity (Body_Id)) then
4388 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4390 -- Body entities present (formals), so chain stuff past them
4394 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4397 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4398 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4399 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4401 -- Case where there are no spec entities, in this case there can be
4402 -- no body entities either, so just move everything.
4404 -- If the body is generated for an expression function, it may have
4405 -- been preanalyzed already, if 'access was applied to it.
4408 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4409 N_Expression_Function
4411 pragma Assert (No (Last_Entity (Body_Id)));
4415 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4416 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4417 Set_First_Entity (Spec_Id, Empty);
4418 Set_Last_Entity (Spec_Id, Empty);
4422 Check_Missing_Return;
4424 -- Now we are going to check for variables that are never modified in
4425 -- the body of the procedure. But first we deal with a special case
4426 -- where we want to modify this check. If the body of the subprogram
4427 -- starts with a raise statement or its equivalent, or if the body
4428 -- consists entirely of a null statement, then it is pretty obvious that
4429 -- it is OK to not reference the parameters. For example, this might be
4430 -- the following common idiom for a stubbed function: statement of the
4431 -- procedure raises an exception. In particular this deals with the
4432 -- common idiom of a stubbed function, which appears something like:
4434 -- function F (A : Integer) return Some_Type;
4437 -- raise Program_Error;
4441 -- Here the purpose of X is simply to satisfy the annoying requirement
4442 -- in Ada that there be at least one return, and we certainly do not
4443 -- want to go posting warnings on X that it is not initialized. On
4444 -- the other hand, if X is entirely unreferenced that should still
4447 -- What we do is to detect these cases, and if we find them, flag the
4448 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4449 -- suppress unwanted warnings. For the case of the function stub above
4450 -- we have a special test to set X as apparently assigned to suppress
4457 -- Skip initial labels (for one thing this occurs when we are in
4458 -- front-end ZCX mode, but in any case it is irrelevant), and also
4459 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
4461 Stm := First (Statements (HSS));
4462 while Nkind (Stm) = N_Label
4463 or else Nkind (Stm) in N_Push_xxx_Label
4468 -- Do the test on the original statement before expansion
4471 Ostm : constant Node_Id := Original_Node (Stm);
4474 -- If explicit raise statement, turn on flag
4476 if Nkind (Ostm) = N_Raise_Statement then
4477 Set_Trivial_Subprogram (Stm);
4479 -- If null statement, and no following statements, turn on flag
4481 elsif Nkind (Stm) = N_Null_Statement
4482 and then Comes_From_Source (Stm)
4483 and then No (Next (Stm))
4485 Set_Trivial_Subprogram (Stm);
4487 -- Check for explicit call cases which likely raise an exception
4489 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4490 if Is_Entity_Name (Name (Ostm)) then
4492 Ent : constant Entity_Id := Entity (Name (Ostm));
4495 -- If the procedure is marked No_Return, then likely it
4496 -- raises an exception, but in any case it is not coming
4497 -- back here, so turn on the flag.
4500 and then Ekind (Ent) = E_Procedure
4501 and then No_Return (Ent)
4503 Set_Trivial_Subprogram (Stm);
4511 -- Check for variables that are never modified
4518 -- If there is a separate spec, then transfer Never_Set_In_Source
4519 -- flags from out parameters to the corresponding entities in the
4520 -- body. The reason we do that is we want to post error flags on
4521 -- the body entities, not the spec entities.
4523 if Present (Spec_Id) then
4524 E1 := First_Entity (Spec_Id);
4525 while Present (E1) loop
4526 if Ekind (E1) = E_Out_Parameter then
4527 E2 := First_Entity (Body_Id);
4528 while Present (E2) loop
4529 exit when Chars (E1) = Chars (E2);
4533 if Present (E2) then
4534 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4542 -- Check references in body
4544 Check_References (Body_Id);
4547 -- Check for nested subprogram, and mark outer level subprogram if so
4553 if Present (Spec_Id) then
4560 Ent := Enclosing_Subprogram (Ent);
4561 exit when No (Ent) or else Is_Subprogram (Ent);
4564 if Present (Ent) then
4565 Set_Has_Nested_Subprogram (Ent);
4569 -- Restore the limited views in the spec, if any, to let the back end
4570 -- process it without running into circularities.
4572 if Exch_Views /= No_Elist then
4573 Restore_Limited_Views (Exch_Views);
4576 if Mask_Types /= No_Elist then
4577 Unmask_Unfrozen_Types (Mask_Types);
4580 if Present (Desig_View) then
4581 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4585 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4586 Restore_Ghost_Mode (Saved_GM);
4587 end Analyze_Subprogram_Body_Helper;
4589 ------------------------------------
4590 -- Analyze_Subprogram_Declaration --
4591 ------------------------------------
4593 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4594 Scop : constant Entity_Id := Current_Scope;
4595 Designator : Entity_Id;
4597 Is_Completion : Boolean;
4598 -- Indicates whether a null procedure declaration is a completion
4601 -- Null procedures are not allowed in SPARK
4603 if Nkind (Specification (N)) = N_Procedure_Specification
4604 and then Null_Present (Specification (N))
4606 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4608 -- Null procedures are allowed in protected types, following the
4609 -- recent AI12-0147.
4611 if Is_Protected_Type (Current_Scope)
4612 and then Ada_Version < Ada_2012
4614 Error_Msg_N ("protected operation cannot be a null procedure", N);
4617 Analyze_Null_Procedure (N, Is_Completion);
4619 -- The null procedure acts as a body, nothing further is needed
4621 if Is_Completion then
4626 Designator := Analyze_Subprogram_Specification (Specification (N));
4628 -- A reference may already have been generated for the unit name, in
4629 -- which case the following call is redundant. However it is needed for
4630 -- declarations that are the rewriting of an expression function.
4632 Generate_Definition (Designator);
4634 -- Set the SPARK mode from the current context (may be overwritten later
4635 -- with explicit pragma). This is not done for entry barrier functions
4636 -- because they are generated outside the protected type and should not
4637 -- carry the mode of the enclosing context.
4639 if Nkind (N) = N_Subprogram_Declaration
4640 and then Is_Entry_Barrier_Function (N)
4644 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4645 Set_SPARK_Pragma_Inherited (Designator);
4648 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4649 -- the body of this subprogram is instantiated or inlined later and out
4650 -- of context. The body uses this attribute to restore the value of the
4653 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4654 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4657 if Debug_Flag_C then
4658 Write_Str ("==> subprogram spec ");
4659 Write_Name (Chars (Designator));
4660 Write_Str (" from ");
4661 Write_Location (Sloc (N));
4666 Validate_RCI_Subprogram_Declaration (N);
4667 New_Overloaded_Entity (Designator);
4668 Check_Delayed_Subprogram (Designator);
4670 -- If the type of the first formal of the current subprogram is a non-
4671 -- generic tagged private type, mark the subprogram as being a private
4672 -- primitive. Ditto if this is a function with controlling result, and
4673 -- the return type is currently private. In both cases, the type of the
4674 -- controlling argument or result must be in the current scope for the
4675 -- operation to be primitive.
4677 if Has_Controlling_Result (Designator)
4678 and then Is_Private_Type (Etype (Designator))
4679 and then Scope (Etype (Designator)) = Current_Scope
4680 and then not Is_Generic_Actual_Type (Etype (Designator))
4682 Set_Is_Private_Primitive (Designator);
4684 elsif Present (First_Formal (Designator)) then
4686 Formal_Typ : constant Entity_Id :=
4687 Etype (First_Formal (Designator));
4689 Set_Is_Private_Primitive (Designator,
4690 Is_Tagged_Type (Formal_Typ)
4691 and then Scope (Formal_Typ) = Current_Scope
4692 and then Is_Private_Type (Formal_Typ)
4693 and then not Is_Generic_Actual_Type (Formal_Typ));
4697 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4700 if Ada_Version >= Ada_2005
4701 and then Comes_From_Source (N)
4702 and then Is_Dispatching_Operation (Designator)
4709 if Has_Controlling_Result (Designator) then
4710 Etyp := Etype (Designator);
4713 E := First_Entity (Designator);
4715 and then Is_Formal (E)
4716 and then not Is_Controlling_Formal (E)
4724 if Is_Access_Type (Etyp) then
4725 Etyp := Directly_Designated_Type (Etyp);
4728 if Is_Interface (Etyp)
4729 and then not Is_Abstract_Subprogram (Designator)
4730 and then not (Ekind (Designator) = E_Procedure
4731 and then Null_Present (Specification (N)))
4733 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4735 -- Specialize error message based on procedures vs. functions,
4736 -- since functions can't be null subprograms.
4738 if Ekind (Designator) = E_Procedure then
4740 ("interface procedure % must be abstract or null", N);
4743 ("interface function % must be abstract", N);
4749 -- What is the following code for, it used to be
4751 -- ??? Set_Suppress_Elaboration_Checks
4752 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4754 -- The following seems equivalent, but a bit dubious
4756 if Elaboration_Checks_Suppressed (Designator) then
4757 Set_Kill_Elaboration_Checks (Designator);
4760 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4761 Set_Categorization_From_Scope (Designator, Scop);
4764 -- For a compilation unit, check for library-unit pragmas
4766 Push_Scope (Designator);
4767 Set_Categorization_From_Pragmas (N);
4768 Validate_Categorization_Dependency (N, Designator);
4772 -- For a compilation unit, set body required. This flag will only be
4773 -- reset if a valid Import or Interface pragma is processed later on.
4775 if Nkind (Parent (N)) = N_Compilation_Unit then
4776 Set_Body_Required (Parent (N), True);
4778 if Ada_Version >= Ada_2005
4779 and then Nkind (Specification (N)) = N_Procedure_Specification
4780 and then Null_Present (Specification (N))
4783 ("null procedure cannot be declared at library level", N);
4787 Generate_Reference_To_Formals (Designator);
4788 Check_Eliminated (Designator);
4790 if Debug_Flag_C then
4792 Write_Str ("<== subprogram spec ");
4793 Write_Name (Chars (Designator));
4794 Write_Str (" from ");
4795 Write_Location (Sloc (N));
4799 if Is_Protected_Type (Current_Scope) then
4801 -- Indicate that this is a protected operation, because it may be
4802 -- used in subsequent declarations within the protected type.
4804 Set_Convention (Designator, Convention_Protected);
4807 List_Inherited_Pre_Post_Aspects (Designator);
4809 if Has_Aspects (N) then
4810 Analyze_Aspect_Specifications (N, Designator);
4812 end Analyze_Subprogram_Declaration;
4814 --------------------------------------
4815 -- Analyze_Subprogram_Specification --
4816 --------------------------------------
4818 -- Reminder: N here really is a subprogram specification (not a subprogram
4819 -- declaration). This procedure is called to analyze the specification in
4820 -- both subprogram bodies and subprogram declarations (specs).
4822 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4823 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4824 -- Determine whether entity E denotes the spec or body of an invariant
4827 ------------------------------------
4828 -- Is_Invariant_Procedure_Or_Body --
4829 ------------------------------------
4831 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4832 Decl : constant Node_Id := Unit_Declaration_Node (E);
4836 if Nkind (Decl) = N_Subprogram_Body then
4837 Spec := Corresponding_Spec (Decl);
4844 and then Ekind (Spec) = E_Procedure
4845 and then (Is_Partial_Invariant_Procedure (Spec)
4846 or else Is_Invariant_Procedure (Spec));
4847 end Is_Invariant_Procedure_Or_Body;
4851 Designator : constant Entity_Id := Defining_Entity (N);
4852 Formals : constant List_Id := Parameter_Specifications (N);
4854 -- Start of processing for Analyze_Subprogram_Specification
4857 -- User-defined operator is not allowed in SPARK, except as a renaming
4859 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4860 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4862 Check_SPARK_05_Restriction
4863 ("user-defined operator is not allowed", N);
4866 -- Proceed with analysis. Do not emit a cross-reference entry if the
4867 -- specification comes from an expression function, because it may be
4868 -- the completion of a previous declaration. It is not, the cross-
4869 -- reference entry will be emitted for the new subprogram declaration.
4871 if Nkind (Parent (N)) /= N_Expression_Function then
4872 Generate_Definition (Designator);
4875 if Nkind (N) = N_Function_Specification then
4876 Set_Ekind (Designator, E_Function);
4877 Set_Mechanism (Designator, Default_Mechanism);
4879 Set_Ekind (Designator, E_Procedure);
4880 Set_Etype (Designator, Standard_Void_Type);
4883 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4884 -- those subprograms which could be inlined in GNATprove mode (because
4885 -- Body_To_Inline is non-Empty) but should not be inlined.
4887 if GNATprove_Mode then
4888 Set_Is_Inlined_Always (Designator);
4891 -- Introduce new scope for analysis of the formals and the return type
4893 Set_Scope (Designator, Current_Scope);
4895 if Present (Formals) then
4896 Push_Scope (Designator);
4897 Process_Formals (Formals, N);
4899 -- Check dimensions in N for formals with default expression
4901 Analyze_Dimension_Formals (N, Formals);
4903 -- Ada 2005 (AI-345): If this is an overriding operation of an
4904 -- inherited interface operation, and the controlling type is
4905 -- a synchronized type, replace the type with its corresponding
4906 -- record, to match the proper signature of an overriding operation.
4907 -- Same processing for an access parameter whose designated type is
4908 -- derived from a synchronized interface.
4910 -- This modification is not done for invariant procedures because
4911 -- the corresponding record may not necessarely be visible when the
4912 -- concurrent type acts as the full view of a private type.
4915 -- type Prot is private with Type_Invariant => ...;
4916 -- procedure ConcInvariant (Obj : Prot);
4918 -- protected type Prot is ...;
4919 -- type Concurrent_Record_Prot is record ...;
4920 -- procedure ConcInvariant (Obj : Prot) is
4922 -- end ConcInvariant;
4925 -- In the example above, both the spec and body of the invariant
4926 -- procedure must utilize the private type as the controlling type.
4928 if Ada_Version >= Ada_2005
4929 and then not Is_Invariant_Procedure_Or_Body (Designator)
4933 Formal_Typ : Entity_Id;
4934 Rec_Typ : Entity_Id;
4935 Desig_Typ : Entity_Id;
4938 Formal := First_Formal (Designator);
4939 while Present (Formal) loop
4940 Formal_Typ := Etype (Formal);
4942 if Is_Concurrent_Type (Formal_Typ)
4943 and then Present (Corresponding_Record_Type (Formal_Typ))
4945 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4947 if Present (Interfaces (Rec_Typ)) then
4948 Set_Etype (Formal, Rec_Typ);
4951 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4952 Desig_Typ := Designated_Type (Formal_Typ);
4954 if Is_Concurrent_Type (Desig_Typ)
4955 and then Present (Corresponding_Record_Type (Desig_Typ))
4957 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4959 if Present (Interfaces (Rec_Typ)) then
4960 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
4965 Next_Formal (Formal);
4972 -- The subprogram scope is pushed and popped around the processing of
4973 -- the return type for consistency with call above to Process_Formals
4974 -- (which itself can call Analyze_Return_Type), and to ensure that any
4975 -- itype created for the return type will be associated with the proper
4978 elsif Nkind (N) = N_Function_Specification then
4979 Push_Scope (Designator);
4980 Analyze_Return_Type (N);
4986 if Nkind (N) = N_Function_Specification then
4988 -- Deal with operator symbol case
4990 if Nkind (Designator) = N_Defining_Operator_Symbol then
4991 Valid_Operator_Definition (Designator);
4994 May_Need_Actuals (Designator);
4996 -- Ada 2005 (AI-251): If the return type is abstract, verify that
4997 -- the subprogram is abstract also. This does not apply to renaming
4998 -- declarations, where abstractness is inherited, and to subprogram
4999 -- bodies generated for stream operations, which become renamings as
5002 -- In case of primitives associated with abstract interface types
5003 -- the check is applied later (see Analyze_Subprogram_Declaration).
5005 if not Nkind_In (Original_Node (Parent (N)),
5006 N_Abstract_Subprogram_Declaration,
5007 N_Formal_Abstract_Subprogram_Declaration,
5008 N_Subprogram_Renaming_Declaration)
5010 if Is_Abstract_Type (Etype (Designator))
5011 and then not Is_Interface (Etype (Designator))
5014 ("function that returns abstract type must be abstract", N);
5016 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5017 -- access result whose designated type is abstract.
5019 elsif Ada_Version >= Ada_2012
5020 and then Nkind (Result_Definition (N)) = N_Access_Definition
5022 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5023 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5026 ("function whose access result designates abstract type "
5027 & "must be abstract", N);
5033 end Analyze_Subprogram_Specification;
5035 -----------------------
5036 -- Check_Conformance --
5037 -----------------------
5039 procedure Check_Conformance
5040 (New_Id : Entity_Id;
5042 Ctype : Conformance_Type;
5044 Conforms : out Boolean;
5045 Err_Loc : Node_Id := Empty;
5046 Get_Inst : Boolean := False;
5047 Skip_Controlling_Formals : Boolean := False)
5049 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5050 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5051 -- If Errmsg is True, then processing continues to post an error message
5052 -- for conformance error on given node. Two messages are output. The
5053 -- first message points to the previous declaration with a general "no
5054 -- conformance" message. The second is the detailed reason, supplied as
5055 -- Msg. The parameter N provide information for a possible & insertion
5056 -- in the message, and also provides the location for posting the
5057 -- message in the absence of a specified Err_Loc location.
5059 function Conventions_Match
5061 Id2 : Entity_Id) return Boolean;
5062 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5065 -----------------------
5066 -- Conformance_Error --
5067 -----------------------
5069 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5076 if No (Err_Loc) then
5082 Error_Msg_Sloc := Sloc (Old_Id);
5085 when Type_Conformant =>
5086 Error_Msg_N -- CODEFIX
5087 ("not type conformant with declaration#!", Enode);
5089 when Mode_Conformant =>
5090 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5092 ("not mode conformant with operation inherited#!",
5096 ("not mode conformant with declaration#!", Enode);
5099 when Subtype_Conformant =>
5100 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5102 ("not subtype conformant with operation inherited#!",
5106 ("not subtype conformant with declaration#!", Enode);
5109 when Fully_Conformant =>
5110 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5111 Error_Msg_N -- CODEFIX
5112 ("not fully conformant with operation inherited#!",
5115 Error_Msg_N -- CODEFIX
5116 ("not fully conformant with declaration#!", Enode);
5120 Error_Msg_NE (Msg, Enode, N);
5122 end Conformance_Error;
5124 -----------------------
5125 -- Conventions_Match --
5126 -----------------------
5128 function Conventions_Match
5130 Id2 : Entity_Id) return Boolean
5133 -- Ignore the conventions of anonymous access-to-subprogram types
5134 -- and subprogram types because these are internally generated and
5135 -- the only way these may receive a convention is if they inherit
5136 -- the convention of a related subprogram.
5138 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5141 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5146 -- Otherwise compare the conventions directly
5149 return Convention (Id1) = Convention (Id2);
5151 end Conventions_Match;
5155 Old_Type : constant Entity_Id := Etype (Old_Id);
5156 New_Type : constant Entity_Id := Etype (New_Id);
5157 Old_Formal : Entity_Id;
5158 New_Formal : Entity_Id;
5159 Access_Types_Match : Boolean;
5160 Old_Formal_Base : Entity_Id;
5161 New_Formal_Base : Entity_Id;
5163 -- Start of processing for Check_Conformance
5168 -- We need a special case for operators, since they don't appear
5171 if Ctype = Type_Conformant then
5172 if Ekind (New_Id) = E_Operator
5173 and then Operator_Matches_Spec (New_Id, Old_Id)
5179 -- If both are functions/operators, check return types conform
5181 if Old_Type /= Standard_Void_Type
5183 New_Type /= Standard_Void_Type
5185 -- If we are checking interface conformance we omit controlling
5186 -- arguments and result, because we are only checking the conformance
5187 -- of the remaining parameters.
5189 if Has_Controlling_Result (Old_Id)
5190 and then Has_Controlling_Result (New_Id)
5191 and then Skip_Controlling_Formals
5195 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5196 if Ctype >= Subtype_Conformant
5197 and then not Predicates_Match (Old_Type, New_Type)
5200 ("\predicate of return type does not match!", New_Id);
5203 ("\return type does not match!", New_Id);
5209 -- Ada 2005 (AI-231): In case of anonymous access types check the
5210 -- null-exclusion and access-to-constant attributes match.
5212 if Ada_Version >= Ada_2005
5213 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5215 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5216 or else Is_Access_Constant (Etype (Old_Type)) /=
5217 Is_Access_Constant (Etype (New_Type)))
5219 Conformance_Error ("\return type does not match!", New_Id);
5223 -- If either is a function/operator and the other isn't, error
5225 elsif Old_Type /= Standard_Void_Type
5226 or else New_Type /= Standard_Void_Type
5228 Conformance_Error ("\functions can only match functions!", New_Id);
5232 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5233 -- If this is a renaming as body, refine error message to indicate that
5234 -- the conflict is with the original declaration. If the entity is not
5235 -- frozen, the conventions don't have to match, the one of the renamed
5236 -- entity is inherited.
5238 if Ctype >= Subtype_Conformant then
5239 if not Conventions_Match (Old_Id, New_Id) then
5240 if not Is_Frozen (New_Id) then
5243 elsif Present (Err_Loc)
5244 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5245 and then Present (Corresponding_Spec (Err_Loc))
5247 Error_Msg_Name_1 := Chars (New_Id);
5249 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5250 Conformance_Error ("\prior declaration for% has convention %!");
5253 Conformance_Error ("\calling conventions do not match!");
5258 elsif Is_Formal_Subprogram (Old_Id)
5259 or else Is_Formal_Subprogram (New_Id)
5261 Conformance_Error ("\formal subprograms not allowed!");
5266 -- Deal with parameters
5268 -- Note: we use the entity information, rather than going directly
5269 -- to the specification in the tree. This is not only simpler, but
5270 -- absolutely necessary for some cases of conformance tests between
5271 -- operators, where the declaration tree simply does not exist.
5273 Old_Formal := First_Formal (Old_Id);
5274 New_Formal := First_Formal (New_Id);
5275 while Present (Old_Formal) and then Present (New_Formal) loop
5276 if Is_Controlling_Formal (Old_Formal)
5277 and then Is_Controlling_Formal (New_Formal)
5278 and then Skip_Controlling_Formals
5280 -- The controlling formals will have different types when
5281 -- comparing an interface operation with its match, but both
5282 -- or neither must be access parameters.
5284 if Is_Access_Type (Etype (Old_Formal))
5286 Is_Access_Type (Etype (New_Formal))
5288 goto Skip_Controlling_Formal;
5291 ("\access parameter does not match!", New_Formal);
5295 -- Ada 2012: Mode conformance also requires that formal parameters
5296 -- be both aliased, or neither.
5298 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5299 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5301 ("\aliased parameter mismatch!", New_Formal);
5305 if Ctype = Fully_Conformant then
5307 -- Names must match. Error message is more accurate if we do
5308 -- this before checking that the types of the formals match.
5310 if Chars (Old_Formal) /= Chars (New_Formal) then
5311 Conformance_Error ("\name& does not match!", New_Formal);
5313 -- Set error posted flag on new formal as well to stop
5314 -- junk cascaded messages in some cases.
5316 Set_Error_Posted (New_Formal);
5320 -- Null exclusion must match
5322 if Null_Exclusion_Present (Parent (Old_Formal))
5324 Null_Exclusion_Present (Parent (New_Formal))
5326 -- Only give error if both come from source. This should be
5327 -- investigated some time, since it should not be needed ???
5329 if Comes_From_Source (Old_Formal)
5331 Comes_From_Source (New_Formal)
5334 ("\null exclusion for& does not match", New_Formal);
5336 -- Mark error posted on the new formal to avoid duplicated
5337 -- complaint about types not matching.
5339 Set_Error_Posted (New_Formal);
5344 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5345 -- case occurs whenever a subprogram is being renamed and one of its
5346 -- parameters imposes a null exclusion. For example:
5348 -- type T is null record;
5349 -- type Acc_T is access T;
5350 -- subtype Acc_T_Sub is Acc_T;
5352 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5353 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5356 Old_Formal_Base := Etype (Old_Formal);
5357 New_Formal_Base := Etype (New_Formal);
5360 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5361 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5364 Access_Types_Match := Ada_Version >= Ada_2005
5366 -- Ensure that this rule is only applied when New_Id is a
5367 -- renaming of Old_Id.
5369 and then Nkind (Parent (Parent (New_Id))) =
5370 N_Subprogram_Renaming_Declaration
5371 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5372 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5373 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5375 -- Now handle the allowed access-type case
5377 and then Is_Access_Type (Old_Formal_Base)
5378 and then Is_Access_Type (New_Formal_Base)
5380 -- The type kinds must match. The only exception occurs with
5381 -- multiple generics of the form:
5384 -- type F is private; type A is private;
5385 -- type F_Ptr is access F; type A_Ptr is access A;
5386 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5387 -- package F_Pack is ... package A_Pack is
5388 -- package F_Inst is
5389 -- new F_Pack (A, A_Ptr, A_P);
5391 -- When checking for conformance between the parameters of A_P
5392 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5393 -- because the compiler has transformed A_Ptr into a subtype of
5394 -- F_Ptr. We catch this case in the code below.
5396 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5398 (Is_Generic_Type (Old_Formal_Base)
5399 and then Is_Generic_Type (New_Formal_Base)
5400 and then Is_Internal (New_Formal_Base)
5401 and then Etype (Etype (New_Formal_Base)) =
5403 and then Directly_Designated_Type (Old_Formal_Base) =
5404 Directly_Designated_Type (New_Formal_Base)
5405 and then ((Is_Itype (Old_Formal_Base)
5406 and then Can_Never_Be_Null (Old_Formal_Base))
5408 (Is_Itype (New_Formal_Base)
5409 and then Can_Never_Be_Null (New_Formal_Base)));
5411 -- Types must always match. In the visible part of an instance,
5412 -- usual overloading rules for dispatching operations apply, and
5413 -- we check base types (not the actual subtypes).
5415 if In_Instance_Visible_Part
5416 and then Is_Dispatching_Operation (New_Id)
5418 if not Conforming_Types
5419 (T1 => Base_Type (Etype (Old_Formal)),
5420 T2 => Base_Type (Etype (New_Formal)),
5422 Get_Inst => Get_Inst)
5423 and then not Access_Types_Match
5425 Conformance_Error ("\type of & does not match!", New_Formal);
5429 elsif not Conforming_Types
5430 (T1 => Old_Formal_Base,
5431 T2 => New_Formal_Base,
5433 Get_Inst => Get_Inst)
5434 and then not Access_Types_Match
5436 -- Don't give error message if old type is Any_Type. This test
5437 -- avoids some cascaded errors, e.g. in case of a bad spec.
5439 if Errmsg and then Old_Formal_Base = Any_Type then
5442 if Ctype >= Subtype_Conformant
5444 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5447 ("\predicate of & does not match!", New_Formal);
5450 ("\type of & does not match!", New_Formal);
5452 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5454 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5462 -- For mode conformance, mode must match
5464 if Ctype >= Mode_Conformant then
5465 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5466 if not Ekind_In (New_Id, E_Function, E_Procedure)
5467 or else not Is_Primitive_Wrapper (New_Id)
5469 Conformance_Error ("\mode of & does not match!", New_Formal);
5473 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5475 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5477 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5480 ("\mode of & does not match!", New_Formal);
5487 -- Part of mode conformance for access types is having the same
5488 -- constant modifier.
5490 elsif Access_Types_Match
5491 and then Is_Access_Constant (Old_Formal_Base) /=
5492 Is_Access_Constant (New_Formal_Base)
5495 ("\constant modifier does not match!", New_Formal);
5500 if Ctype >= Subtype_Conformant then
5502 -- Ada 2005 (AI-231): In case of anonymous access types check
5503 -- the null-exclusion and access-to-constant attributes must
5504 -- match. For null exclusion, we test the types rather than the
5505 -- formals themselves, since the attribute is only set reliably
5506 -- on the formals in the Ada 95 case, and we exclude the case
5507 -- where Old_Formal is marked as controlling, to avoid errors
5508 -- when matching completing bodies with dispatching declarations
5509 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5511 if Ada_Version >= Ada_2005
5512 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5513 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5515 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5516 Can_Never_Be_Null (Etype (New_Formal))
5518 not Is_Controlling_Formal (Old_Formal))
5520 Is_Access_Constant (Etype (Old_Formal)) /=
5521 Is_Access_Constant (Etype (New_Formal)))
5523 -- Do not complain if error already posted on New_Formal. This
5524 -- avoids some redundant error messages.
5526 and then not Error_Posted (New_Formal)
5528 -- It is allowed to omit the null-exclusion in case of stream
5529 -- attribute subprograms. We recognize stream subprograms
5530 -- through their TSS-generated suffix.
5533 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5536 if TSS_Name /= TSS_Stream_Read
5537 and then TSS_Name /= TSS_Stream_Write
5538 and then TSS_Name /= TSS_Stream_Input
5539 and then TSS_Name /= TSS_Stream_Output
5541 -- Here we have a definite conformance error. It is worth
5542 -- special casing the error message for the case of a
5543 -- controlling formal (which excludes null).
5545 if Is_Controlling_Formal (New_Formal) then
5546 Error_Msg_Node_2 := Scope (New_Formal);
5548 ("\controlling formal & of & excludes null, "
5549 & "declaration must exclude null as well",
5552 -- Normal case (couldn't we give more detail here???)
5556 ("\type of & does not match!", New_Formal);
5565 -- Full conformance checks
5567 if Ctype = Fully_Conformant then
5569 -- We have checked already that names match
5571 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5573 -- Check default expressions for in parameters
5576 NewD : constant Boolean :=
5577 Present (Default_Value (New_Formal));
5578 OldD : constant Boolean :=
5579 Present (Default_Value (Old_Formal));
5581 if NewD or OldD then
5583 -- The old default value has been analyzed because the
5584 -- current full declaration will have frozen everything
5585 -- before. The new default value has not been analyzed,
5586 -- so analyze it now before we check for conformance.
5589 Push_Scope (New_Id);
5590 Preanalyze_Spec_Expression
5591 (Default_Value (New_Formal), Etype (New_Formal));
5595 if not (NewD and OldD)
5596 or else not Fully_Conformant_Expressions
5597 (Default_Value (Old_Formal),
5598 Default_Value (New_Formal))
5601 ("\default expression for & does not match!",
5610 -- A couple of special checks for Ada 83 mode. These checks are
5611 -- skipped if either entity is an operator in package Standard,
5612 -- or if either old or new instance is not from the source program.
5614 if Ada_Version = Ada_83
5615 and then Sloc (Old_Id) > Standard_Location
5616 and then Sloc (New_Id) > Standard_Location
5617 and then Comes_From_Source (Old_Id)
5618 and then Comes_From_Source (New_Id)
5621 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5622 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5625 -- Explicit IN must be present or absent in both cases. This
5626 -- test is required only in the full conformance case.
5628 if In_Present (Old_Param) /= In_Present (New_Param)
5629 and then Ctype = Fully_Conformant
5632 ("\(Ada 83) IN must appear in both declarations",
5637 -- Grouping (use of comma in param lists) must be the same
5638 -- This is where we catch a misconformance like:
5641 -- A : Integer; B : Integer
5643 -- which are represented identically in the tree except
5644 -- for the setting of the flags More_Ids and Prev_Ids.
5646 if More_Ids (Old_Param) /= More_Ids (New_Param)
5647 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5650 ("\grouping of & does not match!", New_Formal);
5656 -- This label is required when skipping controlling formals
5658 <<Skip_Controlling_Formal>>
5660 Next_Formal (Old_Formal);
5661 Next_Formal (New_Formal);
5664 if Present (Old_Formal) then
5665 Conformance_Error ("\too few parameters!");
5668 elsif Present (New_Formal) then
5669 Conformance_Error ("\too many parameters!", New_Formal);
5672 end Check_Conformance;
5674 -----------------------
5675 -- Check_Conventions --
5676 -----------------------
5678 procedure Check_Conventions (Typ : Entity_Id) is
5679 Ifaces_List : Elist_Id;
5681 procedure Check_Convention (Op : Entity_Id);
5682 -- Verify that the convention of inherited dispatching operation Op is
5683 -- consistent among all subprograms it overrides. In order to minimize
5684 -- the search, Search_From is utilized to designate a specific point in
5685 -- the list rather than iterating over the whole list once more.
5687 ----------------------
5688 -- Check_Convention --
5689 ----------------------
5691 procedure Check_Convention (Op : Entity_Id) is
5692 Op_Conv : constant Convention_Id := Convention (Op);
5693 Iface_Conv : Convention_Id;
5694 Iface_Elmt : Elmt_Id;
5695 Iface_Prim_Elmt : Elmt_Id;
5696 Iface_Prim : Entity_Id;
5699 Iface_Elmt := First_Elmt (Ifaces_List);
5700 while Present (Iface_Elmt) loop
5702 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5703 while Present (Iface_Prim_Elmt) loop
5704 Iface_Prim := Node (Iface_Prim_Elmt);
5705 Iface_Conv := Convention (Iface_Prim);
5707 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5708 and then Iface_Conv /= Op_Conv
5711 ("inconsistent conventions in primitive operations", Typ);
5713 Error_Msg_Name_1 := Chars (Op);
5714 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5715 Error_Msg_Sloc := Sloc (Op);
5717 if Comes_From_Source (Op) or else No (Alias (Op)) then
5718 if not Present (Overridden_Operation (Op)) then
5719 Error_Msg_N ("\\primitive % defined #", Typ);
5722 ("\\overriding operation % with "
5723 & "convention % defined #", Typ);
5726 else pragma Assert (Present (Alias (Op)));
5727 Error_Msg_Sloc := Sloc (Alias (Op));
5728 Error_Msg_N ("\\inherited operation % with "
5729 & "convention % defined #", Typ);
5732 Error_Msg_Name_1 := Chars (Op);
5733 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5734 Error_Msg_Sloc := Sloc (Iface_Prim);
5735 Error_Msg_N ("\\overridden operation % with "
5736 & "convention % defined #", Typ);
5738 -- Avoid cascading errors
5743 Next_Elmt (Iface_Prim_Elmt);
5746 Next_Elmt (Iface_Elmt);
5748 end Check_Convention;
5752 Prim_Op : Entity_Id;
5753 Prim_Op_Elmt : Elmt_Id;
5755 -- Start of processing for Check_Conventions
5758 if not Has_Interfaces (Typ) then
5762 Collect_Interfaces (Typ, Ifaces_List);
5764 -- The algorithm checks every overriding dispatching operation against
5765 -- all the corresponding overridden dispatching operations, detecting
5766 -- differences in conventions.
5768 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5769 while Present (Prim_Op_Elmt) loop
5770 Prim_Op := Node (Prim_Op_Elmt);
5772 -- A small optimization: skip the predefined dispatching operations
5773 -- since they always have the same convention.
5775 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5776 Check_Convention (Prim_Op);
5779 Next_Elmt (Prim_Op_Elmt);
5781 end Check_Conventions;
5783 ------------------------------
5784 -- Check_Delayed_Subprogram --
5785 ------------------------------
5787 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5790 procedure Possible_Freeze (T : Entity_Id);
5791 -- T is the type of either a formal parameter or of the return type.
5792 -- If T is not yet frozen and needs a delayed freeze, then the
5793 -- subprogram itself must be delayed.
5795 ---------------------
5796 -- Possible_Freeze --
5797 ---------------------
5799 procedure Possible_Freeze (T : Entity_Id) is
5801 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5802 Set_Has_Delayed_Freeze (Designator);
5804 elsif Is_Access_Type (T)
5805 and then Has_Delayed_Freeze (Designated_Type (T))
5806 and then not Is_Frozen (Designated_Type (T))
5808 Set_Has_Delayed_Freeze (Designator);
5811 end Possible_Freeze;
5813 -- Start of processing for Check_Delayed_Subprogram
5816 -- All subprograms, including abstract subprograms, may need a freeze
5817 -- node if some formal type or the return type needs one.
5819 Possible_Freeze (Etype (Designator));
5820 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5822 -- Need delayed freeze if any of the formal types themselves need
5823 -- a delayed freeze and are not yet frozen.
5825 F := First_Formal (Designator);
5826 while Present (F) loop
5827 Possible_Freeze (Etype (F));
5828 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5832 -- Mark functions that return by reference. Note that it cannot be
5833 -- done for delayed_freeze subprograms because the underlying
5834 -- returned type may not be known yet (for private types)
5836 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5838 Typ : constant Entity_Id := Etype (Designator);
5839 Utyp : constant Entity_Id := Underlying_Type (Typ);
5841 if Is_Limited_View (Typ) then
5842 Set_Returns_By_Ref (Designator);
5843 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5844 Set_Returns_By_Ref (Designator);
5848 end Check_Delayed_Subprogram;
5850 ------------------------------------
5851 -- Check_Discriminant_Conformance --
5852 ------------------------------------
5854 procedure Check_Discriminant_Conformance
5859 Old_Discr : Entity_Id := First_Discriminant (Prev);
5860 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5861 New_Discr_Id : Entity_Id;
5862 New_Discr_Type : Entity_Id;
5864 procedure Conformance_Error (Msg : String; N : Node_Id);
5865 -- Post error message for conformance error on given node. Two messages
5866 -- are output. The first points to the previous declaration with a
5867 -- general "no conformance" message. The second is the detailed reason,
5868 -- supplied as Msg. The parameter N provide information for a possible
5869 -- & insertion in the message.
5871 -----------------------
5872 -- Conformance_Error --
5873 -----------------------
5875 procedure Conformance_Error (Msg : String; N : Node_Id) is
5877 Error_Msg_Sloc := Sloc (Prev_Loc);
5878 Error_Msg_N -- CODEFIX
5879 ("not fully conformant with declaration#!", N);
5880 Error_Msg_NE (Msg, N, N);
5881 end Conformance_Error;
5883 -- Start of processing for Check_Discriminant_Conformance
5886 while Present (Old_Discr) and then Present (New_Discr) loop
5887 New_Discr_Id := Defining_Identifier (New_Discr);
5889 -- The subtype mark of the discriminant on the full type has not
5890 -- been analyzed so we do it here. For an access discriminant a new
5893 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5895 Access_Definition (N, Discriminant_Type (New_Discr));
5898 Analyze (Discriminant_Type (New_Discr));
5899 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5901 -- Ada 2005: if the discriminant definition carries a null
5902 -- exclusion, create an itype to check properly for consistency
5903 -- with partial declaration.
5905 if Is_Access_Type (New_Discr_Type)
5906 and then Null_Exclusion_Present (New_Discr)
5909 Create_Null_Excluding_Itype
5910 (T => New_Discr_Type,
5911 Related_Nod => New_Discr,
5912 Scope_Id => Current_Scope);
5916 if not Conforming_Types
5917 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5919 Conformance_Error ("type of & does not match!", New_Discr_Id);
5922 -- Treat the new discriminant as an occurrence of the old one,
5923 -- for navigation purposes, and fill in some semantic
5924 -- information, for completeness.
5926 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5927 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5928 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5933 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5934 Conformance_Error ("name & does not match!", New_Discr_Id);
5938 -- Default expressions must match
5941 NewD : constant Boolean :=
5942 Present (Expression (New_Discr));
5943 OldD : constant Boolean :=
5944 Present (Expression (Parent (Old_Discr)));
5947 if NewD or OldD then
5949 -- The old default value has been analyzed and expanded,
5950 -- because the current full declaration will have frozen
5951 -- everything before. The new default values have not been
5952 -- expanded, so expand now to check conformance.
5955 Preanalyze_Spec_Expression
5956 (Expression (New_Discr), New_Discr_Type);
5959 if not (NewD and OldD)
5960 or else not Fully_Conformant_Expressions
5961 (Expression (Parent (Old_Discr)),
5962 Expression (New_Discr))
5966 ("default expression for & does not match!",
5973 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
5975 if Ada_Version = Ada_83 then
5977 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
5980 -- Grouping (use of comma in param lists) must be the same
5981 -- This is where we catch a misconformance like:
5984 -- A : Integer; B : Integer
5986 -- which are represented identically in the tree except
5987 -- for the setting of the flags More_Ids and Prev_Ids.
5989 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
5990 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
5993 ("grouping of & does not match!", New_Discr_Id);
5999 Next_Discriminant (Old_Discr);
6003 if Present (Old_Discr) then
6004 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6007 elsif Present (New_Discr) then
6009 ("too many discriminants!", Defining_Identifier (New_Discr));
6012 end Check_Discriminant_Conformance;
6014 ----------------------------
6015 -- Check_Fully_Conformant --
6016 ----------------------------
6018 procedure Check_Fully_Conformant
6019 (New_Id : Entity_Id;
6021 Err_Loc : Node_Id := Empty)
6024 pragma Warnings (Off, Result);
6027 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6028 end Check_Fully_Conformant;
6030 --------------------------
6031 -- Check_Limited_Return --
6032 --------------------------
6034 procedure Check_Limited_Return
6040 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6041 -- replaced by anonymous access results. This is an incompatibility with
6042 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6043 -- controllable with special switch. ???
6045 -- A limited interface that is not immutably limited is OK
6047 if Is_Limited_Interface (R_Type)
6049 not (Is_Task_Interface (R_Type)
6050 or else Is_Protected_Interface (R_Type)
6051 or else Is_Synchronized_Interface (R_Type))
6055 elsif Is_Limited_Type (R_Type)
6056 and then not Is_Interface (R_Type)
6057 and then Comes_From_Source (N)
6058 and then not In_Instance_Body
6059 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6061 -- Error in Ada 2005
6063 if Ada_Version >= Ada_2005
6064 and then not Debug_Flag_Dot_L
6065 and then not GNAT_Mode
6068 ("(Ada 2005) cannot copy object of a limited type "
6069 & "(RM-2005 6.5(5.5/2))", Expr);
6071 if Is_Limited_View (R_Type) then
6073 ("\return by reference not permitted in Ada 2005", Expr);
6076 -- Warn in Ada 95 mode, to give folks a heads up about this
6079 -- In GNAT mode, this is just a warning, to allow it to be evilly
6080 -- turned off. Otherwise it is a real error.
6082 -- In a generic context, simplify the warning because it makes no
6083 -- sense to discuss pass-by-reference or copy.
6085 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6086 if Inside_A_Generic then
6088 ("return of limited object not permitted in Ada 2005 "
6089 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6091 elsif Is_Limited_View (R_Type) then
6093 ("return by reference not permitted in Ada 2005 "
6094 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6097 ("cannot copy object of a limited type in Ada 2005 "
6098 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6101 -- Ada 95 mode, and compatibility warnings disabled
6104 pragma Assert (Ada_Version <= Ada_95);
6105 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6106 return; -- skip continuation messages below
6109 if not Inside_A_Generic then
6111 ("\consider switching to return of access type", Expr);
6112 Explain_Limited_Type (R_Type, Expr);
6115 end Check_Limited_Return;
6117 ---------------------------
6118 -- Check_Mode_Conformant --
6119 ---------------------------
6121 procedure Check_Mode_Conformant
6122 (New_Id : Entity_Id;
6124 Err_Loc : Node_Id := Empty;
6125 Get_Inst : Boolean := False)
6128 pragma Warnings (Off, Result);
6131 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6132 end Check_Mode_Conformant;
6134 --------------------------------
6135 -- Check_Overriding_Indicator --
6136 --------------------------------
6138 procedure Check_Overriding_Indicator
6140 Overridden_Subp : Entity_Id;
6141 Is_Primitive : Boolean)
6147 -- No overriding indicator for literals
6149 if Ekind (Subp) = E_Enumeration_Literal then
6152 elsif Ekind (Subp) = E_Entry then
6153 Decl := Parent (Subp);
6155 -- No point in analyzing a malformed operator
6157 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6158 and then Error_Posted (Subp)
6163 Decl := Unit_Declaration_Node (Subp);
6166 if Nkind_In (Decl, N_Subprogram_Body,
6167 N_Subprogram_Body_Stub,
6168 N_Subprogram_Declaration,
6169 N_Abstract_Subprogram_Declaration,
6170 N_Subprogram_Renaming_Declaration)
6172 Spec := Specification (Decl);
6174 elsif Nkind (Decl) = N_Entry_Declaration then
6181 -- The overriding operation is type conformant with the overridden one,
6182 -- but the names of the formals are not required to match. If the names
6183 -- appear permuted in the overriding operation, this is a possible
6184 -- source of confusion that is worth diagnosing. Controlling formals
6185 -- often carry names that reflect the type, and it is not worthwhile
6186 -- requiring that their names match.
6188 if Present (Overridden_Subp)
6189 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6196 Form1 := First_Formal (Subp);
6197 Form2 := First_Formal (Overridden_Subp);
6199 -- If the overriding operation is a synchronized operation, skip
6200 -- the first parameter of the overridden operation, which is
6201 -- implicit in the new one. If the operation is declared in the
6202 -- body it is not primitive and all formals must match.
6204 if Is_Concurrent_Type (Scope (Subp))
6205 and then Is_Tagged_Type (Scope (Subp))
6206 and then not Has_Completion (Scope (Subp))
6208 Form2 := Next_Formal (Form2);
6211 if Present (Form1) then
6212 Form1 := Next_Formal (Form1);
6213 Form2 := Next_Formal (Form2);
6216 while Present (Form1) loop
6217 if not Is_Controlling_Formal (Form1)
6218 and then Present (Next_Formal (Form2))
6219 and then Chars (Form1) = Chars (Next_Formal (Form2))
6221 Error_Msg_Node_2 := Alias (Overridden_Subp);
6222 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6224 ("& does not match corresponding formal of&#",
6229 Next_Formal (Form1);
6230 Next_Formal (Form2);
6235 -- If there is an overridden subprogram, then check that there is no
6236 -- "not overriding" indicator, and mark the subprogram as overriding.
6237 -- This is not done if the overridden subprogram is marked as hidden,
6238 -- which can occur for the case of inherited controlled operations
6239 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6240 -- subprogram is not itself hidden. (Note: This condition could probably
6241 -- be simplified, leaving out the testing for the specific controlled
6242 -- cases, but it seems safer and clearer this way, and echoes similar
6243 -- special-case tests of this kind in other places.)
6245 if Present (Overridden_Subp)
6246 and then (not Is_Hidden (Overridden_Subp)
6248 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6251 and then Present (Alias (Overridden_Subp))
6252 and then not Is_Hidden (Alias (Overridden_Subp))))
6254 if Must_Not_Override (Spec) then
6255 Error_Msg_Sloc := Sloc (Overridden_Subp);
6257 if Ekind (Subp) = E_Entry then
6259 ("entry & overrides inherited operation #", Spec, Subp);
6262 ("subprogram & overrides inherited operation #", Spec, Subp);
6265 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6266 -- as an extension of Root_Controlled, and thus has a useless Adjust
6267 -- operation. This operation should not be inherited by other limited
6268 -- controlled types. An explicit Adjust for them is not overriding.
6270 elsif Must_Override (Spec)
6271 and then Chars (Overridden_Subp) = Name_Adjust
6272 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6273 and then Present (Alias (Overridden_Subp))
6274 and then In_Predefined_Unit (Alias (Overridden_Subp))
6277 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6278 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6280 elsif Is_Subprogram (Subp) then
6281 if Is_Init_Proc (Subp) then
6284 elsif No (Overridden_Operation (Subp)) then
6286 -- For entities generated by Derive_Subprograms the overridden
6287 -- operation is the inherited primitive (which is available
6288 -- through the attribute alias)
6290 if (Is_Dispatching_Operation (Subp)
6291 or else Is_Dispatching_Operation (Overridden_Subp))
6292 and then not Comes_From_Source (Overridden_Subp)
6293 and then Find_Dispatching_Type (Overridden_Subp) =
6294 Find_Dispatching_Type (Subp)
6295 and then Present (Alias (Overridden_Subp))
6296 and then Comes_From_Source (Alias (Overridden_Subp))
6298 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6299 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6302 Set_Overridden_Operation (Subp, Overridden_Subp);
6303 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6308 -- If primitive flag is set or this is a protected operation, then
6309 -- the operation is overriding at the point of its declaration, so
6310 -- warn if necessary. Otherwise it may have been declared before the
6311 -- operation it overrides and no check is required.
6314 and then not Must_Override (Spec)
6315 and then (Is_Primitive
6316 or else Ekind (Scope (Subp)) = E_Protected_Type)
6318 Style.Missing_Overriding (Decl, Subp);
6321 -- If Subp is an operator, it may override a predefined operation, if
6322 -- it is defined in the same scope as the type to which it applies.
6323 -- In that case Overridden_Subp is empty because of our implicit
6324 -- representation for predefined operators. We have to check whether the
6325 -- signature of Subp matches that of a predefined operator. Note that
6326 -- first argument provides the name of the operator, and the second
6327 -- argument the signature that may match that of a standard operation.
6328 -- If the indicator is overriding, then the operator must match a
6329 -- predefined signature, because we know already that there is no
6330 -- explicit overridden operation.
6332 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6333 if Must_Not_Override (Spec) then
6335 -- If this is not a primitive or a protected subprogram, then
6336 -- "not overriding" is illegal.
6339 and then Ekind (Scope (Subp)) /= E_Protected_Type
6341 Error_Msg_N ("overriding indicator only allowed "
6342 & "if subprogram is primitive", Subp);
6344 elsif Can_Override_Operator (Subp) then
6346 ("subprogram& overrides predefined operator ", Spec, Subp);
6349 elsif Must_Override (Spec) then
6350 if No (Overridden_Operation (Subp))
6351 and then not Can_Override_Operator (Subp)
6353 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6356 elsif not Error_Posted (Subp)
6357 and then Style_Check
6358 and then Can_Override_Operator (Subp)
6359 and then not In_Predefined_Unit (Subp)
6361 -- If style checks are enabled, indicate that the indicator is
6362 -- missing. However, at the point of declaration, the type of
6363 -- which this is a primitive operation may be private, in which
6364 -- case the indicator would be premature.
6366 if Has_Private_Declaration (Etype (Subp))
6367 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6371 Style.Missing_Overriding (Decl, Subp);
6375 elsif Must_Override (Spec) then
6376 if Ekind (Subp) = E_Entry then
6377 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6379 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6382 -- If the operation is marked "not overriding" and it's not primitive
6383 -- then an error is issued, unless this is an operation of a task or
6384 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6385 -- has been specified have already been checked above.
6387 elsif Must_Not_Override (Spec)
6388 and then not Is_Primitive
6389 and then Ekind (Subp) /= E_Entry
6390 and then Ekind (Scope (Subp)) /= E_Protected_Type
6393 ("overriding indicator only allowed if subprogram is primitive",
6397 end Check_Overriding_Indicator;
6403 -- Note: this procedure needs to know far too much about how the expander
6404 -- messes with exceptions. The use of the flag Exception_Junk and the
6405 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6406 -- works, but is not very clean. It would be better if the expansion
6407 -- routines would leave Original_Node working nicely, and we could use
6408 -- Original_Node here to ignore all the peculiar expander messing ???
6410 procedure Check_Returns
6414 Proc : Entity_Id := Empty)
6418 procedure Check_Statement_Sequence (L : List_Id);
6419 -- Internal recursive procedure to check a list of statements for proper
6420 -- termination by a return statement (or a transfer of control or a
6421 -- compound statement that is itself internally properly terminated).
6423 ------------------------------
6424 -- Check_Statement_Sequence --
6425 ------------------------------
6427 procedure Check_Statement_Sequence (L : List_Id) is
6432 function Assert_False return Boolean;
6433 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6434 -- rewritten as a null statement when assertions are off. The assert
6435 -- is not active, but it is still enough to kill the warning.
6441 function Assert_False return Boolean is
6442 Orig : constant Node_Id := Original_Node (Last_Stm);
6445 if Nkind (Orig) = N_Pragma
6446 and then Pragma_Name (Orig) = Name_Assert
6447 and then not Error_Posted (Orig)
6450 Arg : constant Node_Id :=
6451 First (Pragma_Argument_Associations (Orig));
6452 Exp : constant Node_Id := Expression (Arg);
6454 return Nkind (Exp) = N_Identifier
6455 and then Chars (Exp) = Name_False;
6465 Raise_Exception_Call : Boolean;
6466 -- Set True if statement sequence terminated by Raise_Exception call
6467 -- or a Reraise_Occurrence call.
6469 -- Start of processing for Check_Statement_Sequence
6472 Raise_Exception_Call := False;
6474 -- Get last real statement
6476 Last_Stm := Last (L);
6478 -- Deal with digging out exception handler statement sequences that
6479 -- have been transformed by the local raise to goto optimization.
6480 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6481 -- optimization has occurred, we are looking at something like:
6484 -- original stmts in block
6488 -- goto L1; | omitted if No_Exception_Propagation
6493 -- goto L3; -- skip handler when exception not raised
6495 -- <<L1>> -- target label for local exception
6509 -- and what we have to do is to dig out the estmts1 and estmts2
6510 -- sequences (which were the original sequences of statements in
6511 -- the exception handlers) and check them.
6513 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6518 exit when Nkind (Stm) /= N_Block_Statement;
6519 exit when not Exception_Junk (Stm);
6522 exit when Nkind (Stm) /= N_Label;
6523 exit when not Exception_Junk (Stm);
6524 Check_Statement_Sequence
6525 (Statements (Handled_Statement_Sequence (Next (Stm))));
6530 exit when Nkind (Stm) /= N_Goto_Statement;
6531 exit when not Exception_Junk (Stm);
6535 -- Don't count pragmas
6537 while Nkind (Last_Stm) = N_Pragma
6539 -- Don't count call to SS_Release (can happen after Raise_Exception)
6542 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6544 Nkind (Name (Last_Stm)) = N_Identifier
6546 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6548 -- Don't count exception junk
6551 (Nkind_In (Last_Stm, N_Goto_Statement,
6553 N_Object_Declaration)
6554 and then Exception_Junk (Last_Stm))
6555 or else Nkind (Last_Stm) in N_Push_xxx_Label
6556 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6558 -- Inserted code, such as finalization calls, is irrelevant: we only
6559 -- need to check original source.
6561 or else Is_Rewrite_Insertion (Last_Stm)
6566 -- Here we have the "real" last statement
6568 Kind := Nkind (Last_Stm);
6570 -- Transfer of control, OK. Note that in the No_Return procedure
6571 -- case, we already diagnosed any explicit return statements, so
6572 -- we can treat them as OK in this context.
6574 if Is_Transfer (Last_Stm) then
6577 -- Check cases of explicit non-indirect procedure calls
6579 elsif Kind = N_Procedure_Call_Statement
6580 and then Is_Entity_Name (Name (Last_Stm))
6582 -- Check call to Raise_Exception procedure which is treated
6583 -- specially, as is a call to Reraise_Occurrence.
6585 -- We suppress the warning in these cases since it is likely that
6586 -- the programmer really does not expect to deal with the case
6587 -- of Null_Occurrence, and thus would find a warning about a
6588 -- missing return curious, and raising Program_Error does not
6589 -- seem such a bad behavior if this does occur.
6591 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6592 -- behavior will be to raise Constraint_Error (see AI-329).
6594 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6596 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6598 Raise_Exception_Call := True;
6600 -- For Raise_Exception call, test first argument, if it is
6601 -- an attribute reference for a 'Identity call, then we know
6602 -- that the call cannot possibly return.
6605 Arg : constant Node_Id :=
6606 Original_Node (First_Actual (Last_Stm));
6608 if Nkind (Arg) = N_Attribute_Reference
6609 and then Attribute_Name (Arg) = Name_Identity
6616 -- If statement, need to look inside if there is an else and check
6617 -- each constituent statement sequence for proper termination.
6619 elsif Kind = N_If_Statement
6620 and then Present (Else_Statements (Last_Stm))
6622 Check_Statement_Sequence (Then_Statements (Last_Stm));
6623 Check_Statement_Sequence (Else_Statements (Last_Stm));
6625 if Present (Elsif_Parts (Last_Stm)) then
6627 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6630 while Present (Elsif_Part) loop
6631 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6639 -- Case statement, check each case for proper termination
6641 elsif Kind = N_Case_Statement then
6645 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6646 while Present (Case_Alt) loop
6647 Check_Statement_Sequence (Statements (Case_Alt));
6648 Next_Non_Pragma (Case_Alt);
6654 -- Block statement, check its handled sequence of statements
6656 elsif Kind = N_Block_Statement then
6662 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6671 -- Loop statement. If there is an iteration scheme, we can definitely
6672 -- fall out of the loop. Similarly if there is an exit statement, we
6673 -- can fall out. In either case we need a following return.
6675 elsif Kind = N_Loop_Statement then
6676 if Present (Iteration_Scheme (Last_Stm))
6677 or else Has_Exit (Entity (Identifier (Last_Stm)))
6681 -- A loop with no exit statement or iteration scheme is either
6682 -- an infinite loop, or it has some other exit (raise/return).
6683 -- In either case, no warning is required.
6689 -- Timed entry call, check entry call and delay alternatives
6691 -- Note: in expanded code, the timed entry call has been converted
6692 -- to a set of expanded statements on which the check will work
6693 -- correctly in any case.
6695 elsif Kind = N_Timed_Entry_Call then
6697 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6698 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6701 -- If statement sequence of entry call alternative is missing,
6702 -- then we can definitely fall through, and we post the error
6703 -- message on the entry call alternative itself.
6705 if No (Statements (ECA)) then
6708 -- If statement sequence of delay alternative is missing, then
6709 -- we can definitely fall through, and we post the error
6710 -- message on the delay alternative itself.
6712 -- Note: if both ECA and DCA are missing the return, then we
6713 -- post only one message, should be enough to fix the bugs.
6714 -- If not we will get a message next time on the DCA when the
6717 elsif No (Statements (DCA)) then
6720 -- Else check both statement sequences
6723 Check_Statement_Sequence (Statements (ECA));
6724 Check_Statement_Sequence (Statements (DCA));
6729 -- Conditional entry call, check entry call and else part
6731 -- Note: in expanded code, the conditional entry call has been
6732 -- converted to a set of expanded statements on which the check
6733 -- will work correctly in any case.
6735 elsif Kind = N_Conditional_Entry_Call then
6737 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6740 -- If statement sequence of entry call alternative is missing,
6741 -- then we can definitely fall through, and we post the error
6742 -- message on the entry call alternative itself.
6744 if No (Statements (ECA)) then
6747 -- Else check statement sequence and else part
6750 Check_Statement_Sequence (Statements (ECA));
6751 Check_Statement_Sequence (Else_Statements (Last_Stm));
6757 -- If we fall through, issue appropriate message
6761 -- Kill warning if last statement is a raise exception call,
6762 -- or a pragma Assert (False). Note that with assertions enabled,
6763 -- such a pragma has been converted into a raise exception call
6764 -- already, so the Assert_False is for the assertions off case.
6766 if not Raise_Exception_Call and then not Assert_False then
6768 -- In GNATprove mode, it is an error to have a missing return
6770 Error_Msg_Warn := SPARK_Mode /= On;
6772 -- Issue error message or warning
6775 ("RETURN statement missing following this statement<<!",
6778 ("\Program_Error ]<<!", Last_Stm);
6781 -- Note: we set Err even though we have not issued a warning
6782 -- because we still have a case of a missing return. This is
6783 -- an extremely marginal case, probably will never be noticed
6784 -- but we might as well get it right.
6788 -- Otherwise we have the case of a procedure marked No_Return
6791 if not Raise_Exception_Call then
6792 if GNATprove_Mode then
6794 ("implied return after this statement would have raised "
6795 & "Program_Error", Last_Stm);
6797 -- In normal compilation mode, do not warn on a generated call
6798 -- (e.g. in the body of a renaming as completion).
6800 elsif Comes_From_Source (Last_Stm) then
6802 ("implied return after this statement will raise "
6803 & "Program_Error??", Last_Stm);
6806 Error_Msg_Warn := SPARK_Mode /= On;
6808 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6812 RE : constant Node_Id :=
6813 Make_Raise_Program_Error (Sloc (Last_Stm),
6814 Reason => PE_Implicit_Return);
6816 Insert_After (Last_Stm, RE);
6820 end Check_Statement_Sequence;
6822 -- Start of processing for Check_Returns
6826 Check_Statement_Sequence (Statements (HSS));
6828 if Present (Exception_Handlers (HSS)) then
6829 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6830 while Present (Handler) loop
6831 Check_Statement_Sequence (Statements (Handler));
6832 Next_Non_Pragma (Handler);
6837 ----------------------------
6838 -- Check_Subprogram_Order --
6839 ----------------------------
6841 procedure Check_Subprogram_Order (N : Node_Id) is
6843 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6844 -- This is used to check if S1 > S2 in the sense required by this test,
6845 -- for example nameab < namec, but name2 < name10.
6847 -----------------------------
6848 -- Subprogram_Name_Greater --
6849 -----------------------------
6851 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6856 -- Deal with special case where names are identical except for a
6857 -- numerical suffix. These are handled specially, taking the numeric
6858 -- ordering from the suffix into account.
6861 while S1 (L1) in '0' .. '9' loop
6866 while S2 (L2) in '0' .. '9' loop
6870 -- If non-numeric parts non-equal, do straight compare
6872 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6875 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6876 -- that a missing suffix is treated as numeric zero in this test.
6880 while L1 < S1'Last loop
6882 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6886 while L2 < S2'Last loop
6888 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6893 end Subprogram_Name_Greater;
6895 -- Start of processing for Check_Subprogram_Order
6898 -- Check body in alpha order if this is option
6901 and then Style_Check_Order_Subprograms
6902 and then Nkind (N) = N_Subprogram_Body
6903 and then Comes_From_Source (N)
6904 and then In_Extended_Main_Source_Unit (N)
6908 renames Scope_Stack.Table
6909 (Scope_Stack.Last).Last_Subprogram_Name;
6911 Body_Id : constant Entity_Id :=
6912 Defining_Entity (Specification (N));
6915 Get_Decoded_Name_String (Chars (Body_Id));
6918 if Subprogram_Name_Greater
6919 (LSN.all, Name_Buffer (1 .. Name_Len))
6921 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6927 LSN := new String'(Name_Buffer (1 .. Name_Len));
6930 end Check_Subprogram_Order;
6932 ------------------------------
6933 -- Check_Subtype_Conformant --
6934 ------------------------------
6936 procedure Check_Subtype_Conformant
6937 (New_Id : Entity_Id;
6939 Err_Loc : Node_Id := Empty;
6940 Skip_Controlling_Formals : Boolean := False;
6941 Get_Inst : Boolean := False)
6944 pragma Warnings (Off, Result);
6947 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6948 Skip_Controlling_Formals => Skip_Controlling_Formals,
6949 Get_Inst => Get_Inst);
6950 end Check_Subtype_Conformant;
6952 -----------------------------------
6953 -- Check_Synchronized_Overriding --
6954 -----------------------------------
6956 procedure Check_Synchronized_Overriding
6957 (Def_Id : Entity_Id;
6958 Overridden_Subp : out Entity_Id)
6960 Ifaces_List : Elist_Id;
6964 function Matches_Prefixed_View_Profile
6965 (Prim_Params : List_Id;
6966 Iface_Params : List_Id) return Boolean;
6967 -- Determine whether a subprogram's parameter profile Prim_Params
6968 -- matches that of a potentially overridden interface subprogram
6969 -- Iface_Params. Also determine if the type of first parameter of
6970 -- Iface_Params is an implemented interface.
6972 -----------------------------------
6973 -- Matches_Prefixed_View_Profile --
6974 -----------------------------------
6976 function Matches_Prefixed_View_Profile
6977 (Prim_Params : List_Id;
6978 Iface_Params : List_Id) return Boolean
6980 function Is_Implemented
6981 (Ifaces_List : Elist_Id;
6982 Iface : Entity_Id) return Boolean;
6983 -- Determine if Iface is implemented by the current task or
6986 --------------------
6987 -- Is_Implemented --
6988 --------------------
6990 function Is_Implemented
6991 (Ifaces_List : Elist_Id;
6992 Iface : Entity_Id) return Boolean
6994 Iface_Elmt : Elmt_Id;
6997 Iface_Elmt := First_Elmt (Ifaces_List);
6998 while Present (Iface_Elmt) loop
6999 if Node (Iface_Elmt) = Iface then
7003 Next_Elmt (Iface_Elmt);
7011 Iface_Id : Entity_Id;
7012 Iface_Param : Node_Id;
7013 Iface_Typ : Entity_Id;
7014 Prim_Id : Entity_Id;
7015 Prim_Param : Node_Id;
7016 Prim_Typ : Entity_Id;
7018 -- Start of processing for Matches_Prefixed_View_Profile
7021 Iface_Param := First (Iface_Params);
7022 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7024 if Is_Access_Type (Iface_Typ) then
7025 Iface_Typ := Designated_Type (Iface_Typ);
7028 Prim_Param := First (Prim_Params);
7030 -- The first parameter of the potentially overridden subprogram must
7031 -- be an interface implemented by Prim.
7033 if not Is_Interface (Iface_Typ)
7034 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7039 -- The checks on the object parameters are done, so move on to the
7040 -- rest of the parameters.
7042 if not In_Scope then
7043 Prim_Param := Next (Prim_Param);
7046 Iface_Param := Next (Iface_Param);
7047 while Present (Iface_Param) and then Present (Prim_Param) loop
7048 Iface_Id := Defining_Identifier (Iface_Param);
7049 Iface_Typ := Find_Parameter_Type (Iface_Param);
7051 Prim_Id := Defining_Identifier (Prim_Param);
7052 Prim_Typ := Find_Parameter_Type (Prim_Param);
7054 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7055 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7056 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7058 Iface_Typ := Designated_Type (Iface_Typ);
7059 Prim_Typ := Designated_Type (Prim_Typ);
7062 -- Case of multiple interface types inside a parameter profile
7064 -- (Obj_Param : in out Iface; ...; Param : Iface)
7066 -- If the interface type is implemented, then the matching type in
7067 -- the primitive should be the implementing record type.
7069 if Ekind (Iface_Typ) = E_Record_Type
7070 and then Is_Interface (Iface_Typ)
7071 and then Is_Implemented (Ifaces_List, Iface_Typ)
7073 if Prim_Typ /= Typ then
7077 -- The two parameters must be both mode and subtype conformant
7079 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7081 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7090 -- One of the two lists contains more parameters than the other
7092 if Present (Iface_Param) or else Present (Prim_Param) then
7097 end Matches_Prefixed_View_Profile;
7099 -- Start of processing for Check_Synchronized_Overriding
7102 Overridden_Subp := Empty;
7104 -- Def_Id must be an entry or a subprogram. We should skip predefined
7105 -- primitives internally generated by the front end; however at this
7106 -- stage predefined primitives are still not fully decorated. As a
7107 -- minor optimization we skip here internally generated subprograms.
7109 if (Ekind (Def_Id) /= E_Entry
7110 and then Ekind (Def_Id) /= E_Function
7111 and then Ekind (Def_Id) /= E_Procedure)
7112 or else not Comes_From_Source (Def_Id)
7117 -- Search for the concurrent declaration since it contains the list of
7118 -- all implemented interfaces. In this case, the subprogram is declared
7119 -- within the scope of a protected or a task type.
7121 if Present (Scope (Def_Id))
7122 and then Is_Concurrent_Type (Scope (Def_Id))
7123 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7125 Typ := Scope (Def_Id);
7128 -- The enclosing scope is not a synchronized type and the subprogram
7131 elsif No (First_Formal (Def_Id)) then
7134 -- The subprogram has formals and hence it may be a primitive of a
7138 Typ := Etype (First_Formal (Def_Id));
7140 if Is_Access_Type (Typ) then
7141 Typ := Directly_Designated_Type (Typ);
7144 if Is_Concurrent_Type (Typ)
7145 and then not Is_Generic_Actual_Type (Typ)
7149 -- This case occurs when the concurrent type is declared within a
7150 -- generic unit. As a result the corresponding record has been built
7151 -- and used as the type of the first formal, we just have to retrieve
7152 -- the corresponding concurrent type.
7154 elsif Is_Concurrent_Record_Type (Typ)
7155 and then not Is_Class_Wide_Type (Typ)
7156 and then Present (Corresponding_Concurrent_Type (Typ))
7158 Typ := Corresponding_Concurrent_Type (Typ);
7166 -- There is no overriding to check if this is an inherited operation in
7167 -- a type derivation for a generic actual.
7169 Collect_Interfaces (Typ, Ifaces_List);
7171 if Is_Empty_Elmt_List (Ifaces_List) then
7175 -- Determine whether entry or subprogram Def_Id overrides a primitive
7176 -- operation that belongs to one of the interfaces in Ifaces_List.
7179 Candidate : Entity_Id := Empty;
7180 Hom : Entity_Id := Empty;
7181 Subp : Entity_Id := Empty;
7184 -- Traverse the homonym chain, looking for a potentially overridden
7185 -- subprogram that belongs to an implemented interface.
7187 Hom := Current_Entity_In_Scope (Def_Id);
7188 while Present (Hom) loop
7192 or else not Is_Overloadable (Subp)
7193 or else not Is_Primitive (Subp)
7194 or else not Is_Dispatching_Operation (Subp)
7195 or else not Present (Find_Dispatching_Type (Subp))
7196 or else not Is_Interface (Find_Dispatching_Type (Subp))
7200 -- Entries and procedures can override abstract or null interface
7203 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7204 and then Ekind (Subp) = E_Procedure
7205 and then Matches_Prefixed_View_Profile
7206 (Parameter_Specifications (Parent (Def_Id)),
7207 Parameter_Specifications (Parent (Subp)))
7211 -- For an overridden subprogram Subp, check whether the mode
7212 -- of its first parameter is correct depending on the kind of
7213 -- synchronized type.
7216 Formal : constant Node_Id := First_Formal (Candidate);
7219 -- In order for an entry or a protected procedure to
7220 -- override, the first parameter of the overridden routine
7221 -- must be of mode "out", "in out", or access-to-variable.
7223 if Ekind_In (Candidate, E_Entry, E_Procedure)
7224 and then Is_Protected_Type (Typ)
7225 and then Ekind (Formal) /= E_In_Out_Parameter
7226 and then Ekind (Formal) /= E_Out_Parameter
7227 and then Nkind (Parameter_Type (Parent (Formal))) /=
7232 -- All other cases are OK since a task entry or routine does
7233 -- not have a restriction on the mode of the first parameter
7234 -- of the overridden interface routine.
7237 Overridden_Subp := Candidate;
7242 -- Functions can override abstract interface functions
7244 elsif Ekind (Def_Id) = E_Function
7245 and then Ekind (Subp) = E_Function
7246 and then Matches_Prefixed_View_Profile
7247 (Parameter_Specifications (Parent (Def_Id)),
7248 Parameter_Specifications (Parent (Subp)))
7249 and then Etype (Def_Id) = Etype (Subp)
7253 -- If an inherited subprogram is implemented by a protected
7254 -- function, then the first parameter of the inherited
7255 -- subprogram shall be of mode in, but not an access-to-
7256 -- variable parameter (RM 9.4(11/9)).
7258 if Present (First_Formal (Subp))
7259 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7261 (not Is_Access_Type (Etype (First_Formal (Subp)))
7263 Is_Access_Constant (Etype (First_Formal (Subp))))
7265 Overridden_Subp := Subp;
7270 Hom := Homonym (Hom);
7273 -- After examining all candidates for overriding, we are left with
7274 -- the best match, which is a mode-incompatible interface routine.
7276 if In_Scope and then Present (Candidate) then
7277 Error_Msg_PT (Def_Id, Candidate);
7280 Overridden_Subp := Candidate;
7283 end Check_Synchronized_Overriding;
7285 ---------------------------
7286 -- Check_Type_Conformant --
7287 ---------------------------
7289 procedure Check_Type_Conformant
7290 (New_Id : Entity_Id;
7292 Err_Loc : Node_Id := Empty)
7295 pragma Warnings (Off, Result);
7298 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7299 end Check_Type_Conformant;
7301 ---------------------------
7302 -- Can_Override_Operator --
7303 ---------------------------
7305 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7309 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7313 Typ := Base_Type (Etype (First_Formal (Subp)));
7315 -- Check explicitly that the operation is a primitive of the type
7317 return Operator_Matches_Spec (Subp, Subp)
7318 and then not Is_Generic_Type (Typ)
7319 and then Scope (Subp) = Scope (Typ)
7320 and then not Is_Class_Wide_Type (Typ);
7322 end Can_Override_Operator;
7324 ----------------------
7325 -- Conforming_Types --
7326 ----------------------
7328 function Conforming_Types
7331 Ctype : Conformance_Type;
7332 Get_Inst : Boolean := False) return Boolean
7334 function Base_Types_Match
7336 Typ_2 : Entity_Id) return Boolean;
7337 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7338 -- in different scopes (e.g. parent and child instances), then verify
7339 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7340 -- the same subtype chain. The whole purpose of this procedure is to
7341 -- prevent spurious ambiguities in an instantiation that may arise if
7342 -- two distinct generic types are instantiated with the same actual.
7344 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7345 -- An access parameter can designate an incomplete type. If the
7346 -- incomplete type is the limited view of a type from a limited_
7347 -- with_clause, check whether the non-limited view is available.
7348 -- If it is a (non-limited) incomplete type, get the full view.
7350 function Matches_Limited_With_View
7352 Typ_2 : Entity_Id) return Boolean;
7353 -- Returns True if and only if either Typ_1 denotes a limited view of
7354 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7355 -- the limited with view of a type is used in a subprogram declaration
7356 -- and the subprogram body is in the scope of a regular with clause for
7357 -- the same unit. In such a case, the two type entities are considered
7358 -- identical for purposes of conformance checking.
7360 ----------------------
7361 -- Base_Types_Match --
7362 ----------------------
7364 function Base_Types_Match
7366 Typ_2 : Entity_Id) return Boolean
7368 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7369 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7372 if Typ_1 = Typ_2 then
7375 elsif Base_1 = Base_2 then
7377 -- The following is too permissive. A more precise test should
7378 -- check that the generic actual is an ancestor subtype of the
7381 -- See code in Find_Corresponding_Spec that applies an additional
7382 -- filter to handle accidental amiguities in instances.
7385 not Is_Generic_Actual_Type (Typ_1)
7386 or else not Is_Generic_Actual_Type (Typ_2)
7387 or else Scope (Typ_1) /= Scope (Typ_2);
7389 -- If Typ_2 is a generic actual type it is declared as the subtype of
7390 -- the actual. If that actual is itself a subtype we need to use its
7391 -- own base type to check for compatibility.
7393 elsif Ekind (Base_2) = Ekind (Typ_2)
7394 and then Base_1 = Base_Type (Base_2)
7398 elsif Ekind (Base_1) = Ekind (Typ_1)
7399 and then Base_2 = Base_Type (Base_1)
7406 end Base_Types_Match;
7408 --------------------------
7409 -- Find_Designated_Type --
7410 --------------------------
7412 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7416 Desig := Directly_Designated_Type (Typ);
7418 if Ekind (Desig) = E_Incomplete_Type then
7420 -- If regular incomplete type, get full view if available
7422 if Present (Full_View (Desig)) then
7423 Desig := Full_View (Desig);
7425 -- If limited view of a type, get non-limited view if available,
7426 -- and check again for a regular incomplete type.
7428 elsif Present (Non_Limited_View (Desig)) then
7429 Desig := Get_Full_View (Non_Limited_View (Desig));
7434 end Find_Designated_Type;
7436 -------------------------------
7437 -- Matches_Limited_With_View --
7438 -------------------------------
7440 function Matches_Limited_With_View
7442 Typ_2 : Entity_Id) return Boolean
7444 function Is_Matching_Limited_View
7446 View : Entity_Id) return Boolean;
7447 -- Determine whether non-limited view View denotes type Typ in some
7448 -- conformant fashion.
7450 ------------------------------
7451 -- Is_Matching_Limited_View --
7452 ------------------------------
7454 function Is_Matching_Limited_View
7456 View : Entity_Id) return Boolean
7458 Root_Typ : Entity_Id;
7459 Root_View : Entity_Id;
7462 -- The non-limited view directly denotes the type
7467 -- The type is a subtype of the non-limited view
7469 elsif Is_Subtype_Of (Typ, View) then
7472 -- Both the non-limited view and the type denote class-wide types
7474 elsif Is_Class_Wide_Type (Typ)
7475 and then Is_Class_Wide_Type (View)
7477 Root_Typ := Root_Type (Typ);
7478 Root_View := Root_Type (View);
7480 if Root_Typ = Root_View then
7483 -- An incomplete tagged type and its full view may receive two
7484 -- distinct class-wide types when the related package has not
7485 -- been analyzed yet.
7488 -- type T is tagged; -- CW_1
7489 -- type T is tagged null record; -- CW_2
7492 -- This is because the package lacks any semantic information
7493 -- that may eventually link both views of T. As a consequence,
7494 -- a client of the limited view of Pack will see CW_2 while a
7495 -- client of the non-limited view of Pack will see CW_1.
7497 elsif Is_Incomplete_Type (Root_Typ)
7498 and then Present (Full_View (Root_Typ))
7499 and then Full_View (Root_Typ) = Root_View
7503 elsif Is_Incomplete_Type (Root_View)
7504 and then Present (Full_View (Root_View))
7505 and then Full_View (Root_View) = Root_Typ
7512 end Is_Matching_Limited_View;
7514 -- Start of processing for Matches_Limited_With_View
7517 -- In some cases a type imported through a limited_with clause, and
7518 -- its non-limited view are both visible, for example in an anonymous
7519 -- access-to-class-wide type in a formal, or when building the body
7520 -- for a subprogram renaming after the subprogram has been frozen.
7521 -- In these cases both entities designate the same type. In addition,
7522 -- if one of them is an actual in an instance, it may be a subtype of
7523 -- the non-limited view of the other.
7525 if From_Limited_With (Typ_1)
7526 and then From_Limited_With (Typ_2)
7527 and then Available_View (Typ_1) = Available_View (Typ_2)
7531 elsif From_Limited_With (Typ_1) then
7532 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7534 elsif From_Limited_With (Typ_2) then
7535 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7540 end Matches_Limited_With_View;
7544 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7546 Type_1 : Entity_Id := T1;
7547 Type_2 : Entity_Id := T2;
7549 -- Start of processing for Conforming_Types
7552 -- The context is an instance association for a formal access-to-
7553 -- subprogram type; the formal parameter types require mapping because
7554 -- they may denote other formal parameters of the generic unit.
7557 Type_1 := Get_Instance_Of (T1);
7558 Type_2 := Get_Instance_Of (T2);
7561 -- If one of the types is a view of the other introduced by a limited
7562 -- with clause, treat these as conforming for all purposes.
7564 if Matches_Limited_With_View (T1, T2) then
7567 elsif Base_Types_Match (Type_1, Type_2) then
7568 if Ctype <= Mode_Conformant then
7573 Subtypes_Statically_Match (Type_1, Type_2)
7574 and then Dimensions_Match (Type_1, Type_2);
7577 elsif Is_Incomplete_Or_Private_Type (Type_1)
7578 and then Present (Full_View (Type_1))
7579 and then Base_Types_Match (Full_View (Type_1), Type_2)
7582 Ctype <= Mode_Conformant
7583 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7585 elsif Ekind (Type_2) = E_Incomplete_Type
7586 and then Present (Full_View (Type_2))
7587 and then Base_Types_Match (Type_1, Full_View (Type_2))
7590 Ctype <= Mode_Conformant
7591 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7593 elsif Is_Private_Type (Type_2)
7594 and then In_Instance
7595 and then Present (Full_View (Type_2))
7596 and then Base_Types_Match (Type_1, Full_View (Type_2))
7599 Ctype <= Mode_Conformant
7600 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7602 -- Another confusion between views in a nested instance with an
7603 -- actual private type whose full view is not in scope.
7605 elsif Ekind (Type_2) = E_Private_Subtype
7606 and then In_Instance
7607 and then Etype (Type_2) = Type_1
7611 -- In Ada 2012, incomplete types (including limited views) can appear
7612 -- as actuals in instantiations.
7614 elsif Is_Incomplete_Type (Type_1)
7615 and then Is_Incomplete_Type (Type_2)
7616 and then (Used_As_Generic_Actual (Type_1)
7617 or else Used_As_Generic_Actual (Type_2))
7622 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7623 -- treated recursively because they carry a signature. As far as
7624 -- conformance is concerned, convention plays no role, and either
7625 -- or both could be access to protected subprograms.
7627 Are_Anonymous_Access_To_Subprogram_Types :=
7628 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7629 E_Anonymous_Access_Protected_Subprogram_Type)
7631 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7632 E_Anonymous_Access_Protected_Subprogram_Type);
7634 -- Test anonymous access type case. For this case, static subtype
7635 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7636 -- the base types because we may have built internal subtype entities
7637 -- to handle null-excluding types (see Process_Formals).
7639 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7641 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7643 -- Ada 2005 (AI-254)
7645 or else Are_Anonymous_Access_To_Subprogram_Types
7648 Desig_1 : Entity_Id;
7649 Desig_2 : Entity_Id;
7652 -- In Ada 2005, access constant indicators must match for
7653 -- subtype conformance.
7655 if Ada_Version >= Ada_2005
7656 and then Ctype >= Subtype_Conformant
7658 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7663 Desig_1 := Find_Designated_Type (Type_1);
7664 Desig_2 := Find_Designated_Type (Type_2);
7666 -- If the context is an instance association for a formal
7667 -- access-to-subprogram type; formal access parameter designated
7668 -- types require mapping because they may denote other formal
7669 -- parameters of the generic unit.
7672 Desig_1 := Get_Instance_Of (Desig_1);
7673 Desig_2 := Get_Instance_Of (Desig_2);
7676 -- It is possible for a Class_Wide_Type to be introduced for an
7677 -- incomplete type, in which case there is a separate class_ wide
7678 -- type for the full view. The types conform if their Etypes
7679 -- conform, i.e. one may be the full view of the other. This can
7680 -- only happen in the context of an access parameter, other uses
7681 -- of an incomplete Class_Wide_Type are illegal.
7683 if Is_Class_Wide_Type (Desig_1)
7685 Is_Class_Wide_Type (Desig_2)
7689 (Etype (Base_Type (Desig_1)),
7690 Etype (Base_Type (Desig_2)), Ctype);
7692 elsif Are_Anonymous_Access_To_Subprogram_Types then
7693 if Ada_Version < Ada_2005 then
7695 Ctype = Type_Conformant
7696 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7698 -- We must check the conformance of the signatures themselves
7702 Conformant : Boolean;
7705 (Desig_1, Desig_2, Ctype, False, Conformant);
7710 -- A limited view of an actual matches the corresponding
7711 -- incomplete formal.
7713 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7714 and then From_Limited_With (Desig_2)
7715 and then Used_As_Generic_Actual (Etype (Desig_2))
7720 return Base_Type (Desig_1) = Base_Type (Desig_2)
7721 and then (Ctype = Type_Conformant
7723 Subtypes_Statically_Match (Desig_1, Desig_2));
7727 -- Otherwise definitely no match
7730 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7731 and then Is_Access_Type (Type_2))
7732 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7733 and then Is_Access_Type (Type_1)))
7736 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7738 May_Hide_Profile := True;
7743 end Conforming_Types;
7745 --------------------------
7746 -- Create_Extra_Formals --
7747 --------------------------
7749 procedure Create_Extra_Formals (E : Entity_Id) is
7750 First_Extra : Entity_Id := Empty;
7752 Last_Extra : Entity_Id := Empty;
7754 function Add_Extra_Formal
7755 (Assoc_Entity : Entity_Id;
7758 Suffix : String) return Entity_Id;
7759 -- Add an extra formal to the current list of formals and extra formals.
7760 -- The extra formal is added to the end of the list of extra formals,
7761 -- and also returned as the result. These formals are always of mode IN.
7762 -- The new formal has the type Typ, is declared in Scope, and its name
7763 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7764 -- The following suffixes are currently used. They should not be changed
7765 -- without coordinating with CodePeer, which makes use of these to
7766 -- provide better messages.
7768 -- O denotes the Constrained bit.
7769 -- L denotes the accessibility level.
7770 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7771 -- the full list in exp_ch6.BIP_Formal_Kind.
7773 ----------------------
7774 -- Add_Extra_Formal --
7775 ----------------------
7777 function Add_Extra_Formal
7778 (Assoc_Entity : Entity_Id;
7781 Suffix : String) return Entity_Id
7783 EF : constant Entity_Id :=
7784 Make_Defining_Identifier (Sloc (Assoc_Entity),
7785 Chars => New_External_Name (Chars (Assoc_Entity),
7789 -- A little optimization. Never generate an extra formal for the
7790 -- _init operand of an initialization procedure, since it could
7793 if Chars (Formal) = Name_uInit then
7797 Set_Ekind (EF, E_In_Parameter);
7798 Set_Actual_Subtype (EF, Typ);
7799 Set_Etype (EF, Typ);
7800 Set_Scope (EF, Scope);
7801 Set_Mechanism (EF, Default_Mechanism);
7802 Set_Formal_Validity (EF);
7804 if No (First_Extra) then
7806 Set_Extra_Formals (Scope, First_Extra);
7809 if Present (Last_Extra) then
7810 Set_Extra_Formal (Last_Extra, EF);
7816 end Add_Extra_Formal;
7820 Formal_Type : Entity_Id;
7821 P_Formal : Entity_Id := Empty;
7823 -- Start of processing for Create_Extra_Formals
7826 -- We never generate extra formals if expansion is not active because we
7827 -- don't need them unless we are generating code.
7829 if not Expander_Active then
7833 -- No need to generate extra formals in interface thunks whose target
7834 -- primitive has no extra formals.
7836 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7840 -- If this is a derived subprogram then the subtypes of the parent
7841 -- subprogram's formal parameters will be used to determine the need
7842 -- for extra formals.
7844 if Is_Overloadable (E) and then Present (Alias (E)) then
7845 P_Formal := First_Formal (Alias (E));
7848 Formal := First_Formal (E);
7849 while Present (Formal) loop
7850 Last_Extra := Formal;
7851 Next_Formal (Formal);
7854 -- If Extra_Formals were already created, don't do it again. This
7855 -- situation may arise for subprogram types created as part of
7856 -- dispatching calls (see Expand_Dispatching_Call)
7858 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7862 -- If the subprogram is a predefined dispatching subprogram then don't
7863 -- generate any extra constrained or accessibility level formals. In
7864 -- general we suppress these for internal subprograms (by not calling
7865 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7866 -- generated stream attributes do get passed through because extra
7867 -- build-in-place formals are needed in some cases (limited 'Input).
7869 if Is_Predefined_Internal_Operation (E) then
7870 goto Test_For_Func_Result_Extras;
7873 Formal := First_Formal (E);
7874 while Present (Formal) loop
7876 -- Create extra formal for supporting the attribute 'Constrained.
7877 -- The case of a private type view without discriminants also
7878 -- requires the extra formal if the underlying type has defaulted
7881 if Ekind (Formal) /= E_In_Parameter then
7882 if Present (P_Formal) then
7883 Formal_Type := Etype (P_Formal);
7885 Formal_Type := Etype (Formal);
7888 -- Do not produce extra formals for Unchecked_Union parameters.
7889 -- Jump directly to the end of the loop.
7891 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7892 goto Skip_Extra_Formal_Generation;
7895 if not Has_Discriminants (Formal_Type)
7896 and then Ekind (Formal_Type) in Private_Kind
7897 and then Present (Underlying_Type (Formal_Type))
7899 Formal_Type := Underlying_Type (Formal_Type);
7902 -- Suppress the extra formal if formal's subtype is constrained or
7903 -- indefinite, or we're compiling for Ada 2012 and the underlying
7904 -- type is tagged and limited. In Ada 2012, a limited tagged type
7905 -- can have defaulted discriminants, but 'Constrained is required
7906 -- to return True, so the formal is never needed (see AI05-0214).
7907 -- Note that this ensures consistency of calling sequences for
7908 -- dispatching operations when some types in a class have defaults
7909 -- on discriminants and others do not (and requiring the extra
7910 -- formal would introduce distributed overhead).
7912 -- If the type does not have a completion yet, treat as prior to
7913 -- Ada 2012 for consistency.
7915 if Has_Discriminants (Formal_Type)
7916 and then not Is_Constrained (Formal_Type)
7917 and then Is_Definite_Subtype (Formal_Type)
7918 and then (Ada_Version < Ada_2012
7919 or else No (Underlying_Type (Formal_Type))
7921 (Is_Limited_Type (Formal_Type)
7924 (Underlying_Type (Formal_Type)))))
7926 Set_Extra_Constrained
7927 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7931 -- Create extra formal for supporting accessibility checking. This
7932 -- is done for both anonymous access formals and formals of named
7933 -- access types that are marked as controlling formals. The latter
7934 -- case can occur when Expand_Dispatching_Call creates a subprogram
7935 -- type and substitutes the types of access-to-class-wide actuals
7936 -- for the anonymous access-to-specific-type of controlling formals.
7937 -- Base_Type is applied because in cases where there is a null
7938 -- exclusion the formal may have an access subtype.
7940 -- This is suppressed if we specifically suppress accessibility
7941 -- checks at the package level for either the subprogram, or the
7942 -- package in which it resides. However, we do not suppress it
7943 -- simply if the scope has accessibility checks suppressed, since
7944 -- this could cause trouble when clients are compiled with a
7945 -- different suppression setting. The explicit checks at the
7946 -- package level are safe from this point of view.
7948 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7949 or else (Is_Controlling_Formal (Formal)
7950 and then Is_Access_Type (Base_Type (Etype (Formal)))))
7952 (Explicit_Suppress (E, Accessibility_Check)
7954 Explicit_Suppress (Scope (E), Accessibility_Check))
7957 or else Present (Extra_Accessibility (P_Formal)))
7959 Set_Extra_Accessibility
7960 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
7963 -- This label is required when skipping extra formal generation for
7964 -- Unchecked_Union parameters.
7966 <<Skip_Extra_Formal_Generation>>
7968 if Present (P_Formal) then
7969 Next_Formal (P_Formal);
7972 Next_Formal (Formal);
7975 <<Test_For_Func_Result_Extras>>
7977 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
7978 -- function call is ... determined by the point of call ...".
7980 if Needs_Result_Accessibility_Level (E) then
7981 Set_Extra_Accessibility_Of_Result
7982 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
7985 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
7986 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
7988 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
7990 Result_Subt : constant Entity_Id := Etype (E);
7991 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
7992 Formal_Typ : Entity_Id;
7993 Subp_Decl : Node_Id;
7995 Discard : Entity_Id;
7996 pragma Warnings (Off, Discard);
7999 -- In the case of functions with unconstrained result subtypes,
8000 -- add a 4-state formal indicating whether the return object is
8001 -- allocated by the caller (1), or should be allocated by the
8002 -- callee on the secondary stack (2), in the global heap (3), or
8003 -- in a user-defined storage pool (4). For the moment we just use
8004 -- Natural for the type of this formal. Note that this formal
8005 -- isn't usually needed in the case where the result subtype is
8006 -- constrained, but it is needed when the function has a tagged
8007 -- result, because generally such functions can be called in a
8008 -- dispatching context and such calls must be handled like calls
8009 -- to a class-wide function.
8011 if Needs_BIP_Alloc_Form (E) then
8014 (E, Standard_Natural,
8015 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8017 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8018 -- use a user-defined pool. This formal is not added on
8019 -- ZFP as those targets do not support pools.
8021 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8024 (E, RTE (RE_Root_Storage_Pool_Ptr),
8025 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8029 -- In the case of functions whose result type needs finalization,
8030 -- add an extra formal which represents the finalization master.
8032 if Needs_BIP_Finalization_Master (E) then
8035 (E, RTE (RE_Finalization_Master_Ptr),
8036 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8039 -- When the result type contains tasks, add two extra formals: the
8040 -- master of the tasks to be created, and the caller's activation
8043 if Has_Task (Full_Subt) then
8046 (E, RTE (RE_Master_Id),
8047 E, BIP_Formal_Suffix (BIP_Task_Master));
8050 (E, RTE (RE_Activation_Chain_Access),
8051 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8054 -- All build-in-place functions get an extra formal that will be
8055 -- passed the address of the return object within the caller.
8058 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8060 Set_Directly_Designated_Type (Formal_Typ, Result_Subt);
8061 Set_Etype (Formal_Typ, Formal_Typ);
8062 Set_Depends_On_Private
8063 (Formal_Typ, Has_Private_Component (Formal_Typ));
8064 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8065 Set_Is_Access_Constant (Formal_Typ, False);
8067 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8068 -- the designated type comes from the limited view (for back-end
8071 Set_From_Limited_With
8072 (Formal_Typ, From_Limited_With (Result_Subt));
8074 Layout_Type (Formal_Typ);
8076 -- Force the definition of the Itype in case of internal function
8077 -- calls within the same or nested scope.
8079 if Is_Subprogram_Or_Generic_Subprogram (E) then
8080 Subp_Decl := Parent (E);
8082 -- The insertion point for an Itype reference should be after
8083 -- the unit declaration node of the subprogram. An exception
8084 -- to this are inherited operations from a parent type in which
8085 -- case the derived type acts as their parent.
8087 if Nkind_In (Subp_Decl, N_Function_Specification,
8088 N_Procedure_Specification)
8090 Subp_Decl := Parent (Subp_Decl);
8093 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8098 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8101 end Create_Extra_Formals;
8103 -----------------------------
8104 -- Enter_Overloaded_Entity --
8105 -----------------------------
8107 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8108 function Matches_Predefined_Op return Boolean;
8109 -- This returns an approximation of whether S matches a predefined
8110 -- operator, based on the operator symbol, and the parameter and result
8111 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8113 ---------------------------
8114 -- Matches_Predefined_Op --
8115 ---------------------------
8117 function Matches_Predefined_Op return Boolean is
8118 Formal_1 : constant Entity_Id := First_Formal (S);
8119 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8120 Op : constant Name_Id := Chars (S);
8121 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8122 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8127 if Present (Formal_2) then
8129 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8132 -- All but "&" and "**" have same-types parameters
8141 if Type_1 /= Type_2 then
8146 -- Check parameter and result types
8154 Is_Boolean_Type (Result_Type)
8155 and then Result_Type = Type_1;
8161 Is_Integer_Type (Result_Type)
8162 and then Result_Type = Type_1;
8170 Is_Numeric_Type (Result_Type)
8171 and then Result_Type = Type_1;
8177 Is_Boolean_Type (Result_Type)
8178 and then not Is_Limited_Type (Type_1);
8186 Is_Boolean_Type (Result_Type)
8187 and then (Is_Array_Type (Type_1)
8188 or else Is_Scalar_Type (Type_1));
8190 when Name_Op_Concat =>
8191 return Is_Array_Type (Result_Type);
8193 when Name_Op_Expon =>
8195 (Is_Integer_Type (Result_Type)
8196 or else Is_Floating_Point_Type (Result_Type))
8197 and then Result_Type = Type_1
8198 and then Type_2 = Standard_Integer;
8201 raise Program_Error;
8214 Is_Numeric_Type (Result_Type)
8215 and then Result_Type = Type_1;
8219 Is_Boolean_Type (Result_Type)
8220 and then Result_Type = Type_1;
8223 raise Program_Error;
8226 end Matches_Predefined_Op;
8230 E : Entity_Id := Current_Entity_In_Scope (S);
8231 C_E : Entity_Id := Current_Entity (S);
8233 -- Start of processing for Enter_Overloaded_Entity
8237 Set_Has_Homonym (E);
8238 Set_Has_Homonym (S);
8241 Set_Is_Immediately_Visible (S);
8242 Set_Scope (S, Current_Scope);
8244 -- Chain new entity if front of homonym in current scope, so that
8245 -- homonyms are contiguous.
8247 if Present (E) and then E /= C_E then
8248 while Homonym (C_E) /= E loop
8249 C_E := Homonym (C_E);
8252 Set_Homonym (C_E, S);
8256 Set_Current_Entity (S);
8261 if Is_Inherited_Operation (S) then
8262 Append_Inherited_Subprogram (S);
8264 Append_Entity (S, Current_Scope);
8267 Set_Public_Status (S);
8269 if Debug_Flag_E then
8270 Write_Str ("New overloaded entity chain: ");
8271 Write_Name (Chars (S));
8274 while Present (E) loop
8275 Write_Str (" "); Write_Int (Int (E));
8282 -- Generate warning for hiding
8285 and then Comes_From_Source (S)
8286 and then In_Extended_Main_Source_Unit (S)
8293 -- Warn unless genuine overloading. Do not emit warning on
8294 -- hiding predefined operators in Standard (these are either an
8295 -- (artifact of our implicit declarations, or simple noise) but
8296 -- keep warning on a operator defined on a local subtype, because
8297 -- of the real danger that different operators may be applied in
8298 -- various parts of the program.
8300 -- Note that if E and S have the same scope, there is never any
8301 -- hiding. Either the two conflict, and the program is illegal,
8302 -- or S is overriding an implicit inherited subprogram.
8304 if Scope (E) /= Scope (S)
8305 and then (not Is_Overloadable (E)
8306 or else Subtype_Conformant (E, S))
8307 and then (Is_Immediately_Visible (E)
8308 or else Is_Potentially_Use_Visible (S))
8310 if Scope (E) = Standard_Standard then
8311 if Nkind (S) = N_Defining_Operator_Symbol
8312 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8314 and then Matches_Predefined_Op
8317 ("declaration of & hides predefined operator?h?", S);
8320 -- E not immediately within Standard
8323 Error_Msg_Sloc := Sloc (E);
8324 Error_Msg_N ("declaration of & hides one #?h?", S);
8329 end Enter_Overloaded_Entity;
8331 -----------------------------
8332 -- Check_Untagged_Equality --
8333 -----------------------------
8335 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8336 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8337 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8341 -- This check applies only if we have a subprogram declaration with an
8342 -- untagged record type.
8344 if Nkind (Decl) /= N_Subprogram_Declaration
8345 or else not Is_Record_Type (Typ)
8346 or else Is_Tagged_Type (Typ)
8351 -- In Ada 2012 case, we will output errors or warnings depending on
8352 -- the setting of debug flag -gnatd.E.
8354 if Ada_Version >= Ada_2012 then
8355 Error_Msg_Warn := Debug_Flag_Dot_EE;
8357 -- In earlier versions of Ada, nothing to do unless we are warning on
8358 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8361 if not Warn_On_Ada_2012_Compatibility then
8366 -- Cases where the type has already been frozen
8368 if Is_Frozen (Typ) then
8370 -- If the type is not declared in a package, or if we are in the body
8371 -- of the package or in some other scope, the new operation is not
8372 -- primitive, and therefore legal, though suspicious. Should we
8373 -- generate a warning in this case ???
8375 if Ekind (Scope (Typ)) /= E_Package
8376 or else Scope (Typ) /= Current_Scope
8380 -- If the type is a generic actual (sub)type, the operation is not
8381 -- primitive either because the base type is declared elsewhere.
8383 elsif Is_Generic_Actual_Type (Typ) then
8386 -- Here we have a definite error of declaration after freezing
8389 if Ada_Version >= Ada_2012 then
8391 ("equality operator must be declared before type & is "
8392 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8394 -- In Ada 2012 mode with error turned to warning, output one
8395 -- more warning to warn that the equality operation may not
8396 -- compose. This is the consequence of ignoring the error.
8398 if Error_Msg_Warn then
8399 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8404 ("equality operator must be declared before type& is "
8405 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8408 -- If we are in the package body, we could just move the
8409 -- declaration to the package spec, so add a message saying that.
8411 if In_Package_Body (Scope (Typ)) then
8412 if Ada_Version >= Ada_2012 then
8414 ("\move declaration to package spec<<", Eq_Op);
8417 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8420 -- Otherwise try to find the freezing point
8423 Obj_Decl := Next (Parent (Typ));
8424 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8425 if Nkind (Obj_Decl) = N_Object_Declaration
8426 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8428 -- Freezing point, output warnings
8430 if Ada_Version >= Ada_2012 then
8432 ("type& is frozen by declaration??", Obj_Decl, Typ);
8434 ("\an equality operator cannot be declared after "
8439 ("type& is frozen by declaration (Ada 2012)?y?",
8442 ("\an equality operator cannot be declared after "
8443 & "this point (Ada 2012)?y?",
8455 -- Here if type is not frozen yet. It is illegal to have a primitive
8456 -- equality declared in the private part if the type is visible.
8458 elsif not In_Same_List (Parent (Typ), Decl)
8459 and then not Is_Limited_Type (Typ)
8461 -- Shouldn't we give an RM reference here???
8463 if Ada_Version >= Ada_2012 then
8465 ("equality operator appears too late<<", Eq_Op);
8468 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8471 -- No error detected
8476 end Check_Untagged_Equality;
8478 -----------------------------
8479 -- Find_Corresponding_Spec --
8480 -----------------------------
8482 function Find_Corresponding_Spec
8484 Post_Error : Boolean := True) return Entity_Id
8486 Spec : constant Node_Id := Specification (N);
8487 Designator : constant Entity_Id := Defining_Entity (Spec);
8491 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8492 -- Even if fully conformant, a body may depend on a generic actual when
8493 -- the spec does not, or vice versa, in which case they were distinct
8494 -- entities in the generic.
8496 -------------------------------
8497 -- Different_Generic_Profile --
8498 -------------------------------
8500 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8503 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8504 -- Check that the types of corresponding formals have the same
8505 -- generic actual if any. We have to account for subtypes of a
8506 -- generic formal, declared between a spec and a body, which may
8507 -- appear distinct in an instance but matched in the generic, and
8508 -- the subtype may be used either in the spec or the body of the
8509 -- subprogram being checked.
8511 -------------------------
8512 -- Same_Generic_Actual --
8513 -------------------------
8515 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8517 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8518 -- Predicate to check whether S1 is a subtype of S2 in the source
8521 -------------------------
8522 -- Is_Declared_Subtype --
8523 -------------------------
8525 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8527 return Comes_From_Source (Parent (S1))
8528 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8529 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8530 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8531 end Is_Declared_Subtype;
8533 -- Start of processing for Same_Generic_Actual
8536 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8537 or else Is_Declared_Subtype (T1, T2)
8538 or else Is_Declared_Subtype (T2, T1);
8539 end Same_Generic_Actual;
8541 -- Start of processing for Different_Generic_Profile
8544 if not In_Instance then
8547 elsif Ekind (E) = E_Function
8548 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8553 F1 := First_Formal (Designator);
8554 F2 := First_Formal (E);
8555 while Present (F1) loop
8556 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8565 end Different_Generic_Profile;
8567 -- Start of processing for Find_Corresponding_Spec
8570 E := Current_Entity (Designator);
8571 while Present (E) loop
8573 -- We are looking for a matching spec. It must have the same scope,
8574 -- and the same name, and either be type conformant, or be the case
8575 -- of a library procedure spec and its body (which belong to one
8576 -- another regardless of whether they are type conformant or not).
8578 if Scope (E) = Current_Scope then
8579 if Current_Scope = Standard_Standard
8580 or else (Ekind (E) = Ekind (Designator)
8581 and then Type_Conformant (E, Designator))
8583 -- Within an instantiation, we know that spec and body are
8584 -- subtype conformant, because they were subtype conformant in
8585 -- the generic. We choose the subtype-conformant entity here as
8586 -- well, to resolve spurious ambiguities in the instance that
8587 -- were not present in the generic (i.e. when two different
8588 -- types are given the same actual). If we are looking for a
8589 -- spec to match a body, full conformance is expected.
8593 -- Inherit the convention and "ghostness" of the matching
8594 -- spec to ensure proper full and subtype conformance.
8596 Set_Convention (Designator, Convention (E));
8598 -- Skip past subprogram bodies and subprogram renamings that
8599 -- may appear to have a matching spec, but that aren't fully
8600 -- conformant with it. That can occur in cases where an
8601 -- actual type causes unrelated homographs in the instance.
8603 if Nkind_In (N, N_Subprogram_Body,
8604 N_Subprogram_Renaming_Declaration)
8605 and then Present (Homonym (E))
8606 and then not Fully_Conformant (Designator, E)
8610 elsif not Subtype_Conformant (Designator, E) then
8613 elsif Different_Generic_Profile (E) then
8618 -- Ada 2012 (AI05-0165): For internally generated bodies of
8619 -- null procedures locate the internally generated spec. We
8620 -- enforce mode conformance since a tagged type may inherit
8621 -- from interfaces several null primitives which differ only
8622 -- in the mode of the formals.
8624 if not (Comes_From_Source (E))
8625 and then Is_Null_Procedure (E)
8626 and then not Mode_Conformant (Designator, E)
8630 -- For null procedures coming from source that are completions,
8631 -- analysis of the generated body will establish the link.
8633 elsif Comes_From_Source (E)
8634 and then Nkind (Spec) = N_Procedure_Specification
8635 and then Null_Present (Spec)
8639 -- Expression functions can be completions, but cannot be
8640 -- completed by an explicit body.
8642 elsif Comes_From_Source (E)
8643 and then Comes_From_Source (N)
8644 and then Nkind (N) = N_Subprogram_Body
8645 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8646 N_Expression_Function
8648 Error_Msg_Sloc := Sloc (E);
8649 Error_Msg_N ("body conflicts with expression function#", N);
8652 elsif not Has_Completion (E) then
8653 if Nkind (N) /= N_Subprogram_Body_Stub then
8654 Set_Corresponding_Spec (N, E);
8657 Set_Has_Completion (E);
8660 elsif Nkind (Parent (N)) = N_Subunit then
8662 -- If this is the proper body of a subunit, the completion
8663 -- flag is set when analyzing the stub.
8667 -- If E is an internal function with a controlling result that
8668 -- was created for an operation inherited by a null extension,
8669 -- it may be overridden by a body without a previous spec (one
8670 -- more reason why these should be shunned). In that case we
8671 -- remove the generated body if present, because the current
8672 -- one is the explicit overriding.
8674 elsif Ekind (E) = E_Function
8675 and then Ada_Version >= Ada_2005
8676 and then not Comes_From_Source (E)
8677 and then Has_Controlling_Result (E)
8678 and then Is_Null_Extension (Etype (E))
8679 and then Comes_From_Source (Spec)
8681 Set_Has_Completion (E, False);
8684 and then Nkind (Parent (E)) = N_Function_Specification
8687 (Unit_Declaration_Node
8688 (Corresponding_Body (Unit_Declaration_Node (E))));
8692 -- If expansion is disabled, or if the wrapper function has
8693 -- not been generated yet, this a late body overriding an
8694 -- inherited operation, or it is an overriding by some other
8695 -- declaration before the controlling result is frozen. In
8696 -- either case this is a declaration of a new entity.
8702 -- If the body already exists, then this is an error unless
8703 -- the previous declaration is the implicit declaration of a
8704 -- derived subprogram. It is also legal for an instance to
8705 -- contain type conformant overloadable declarations (but the
8706 -- generic declaration may not), per 8.3(26/2).
8708 elsif No (Alias (E))
8709 and then not Is_Intrinsic_Subprogram (E)
8710 and then not In_Instance
8713 Error_Msg_Sloc := Sloc (E);
8715 if Is_Imported (E) then
8717 ("body not allowed for imported subprogram & declared#",
8720 Error_Msg_NE ("duplicate body for & declared#", N, E);
8724 -- Child units cannot be overloaded, so a conformance mismatch
8725 -- between body and a previous spec is an error.
8727 elsif Is_Child_Unit (E)
8729 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8731 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8736 ("body of child unit does not match previous declaration", N);
8744 -- On exit, we know that no previous declaration of subprogram exists
8747 end Find_Corresponding_Spec;
8749 ----------------------
8750 -- Fully_Conformant --
8751 ----------------------
8753 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8756 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8758 end Fully_Conformant;
8760 ----------------------------------
8761 -- Fully_Conformant_Expressions --
8762 ----------------------------------
8764 function Fully_Conformant_Expressions
8765 (Given_E1 : Node_Id;
8766 Given_E2 : Node_Id) return Boolean
8768 E1 : constant Node_Id := Original_Node (Given_E1);
8769 E2 : constant Node_Id := Original_Node (Given_E2);
8770 -- We always test conformance on original nodes, since it is possible
8771 -- for analysis and/or expansion to make things look as though they
8772 -- conform when they do not, e.g. by converting 1+2 into 3.
8774 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8775 renames Fully_Conformant_Expressions;
8777 function FCL (L1, L2 : List_Id) return Boolean;
8778 -- Compare elements of two lists for conformance. Elements have to be
8779 -- conformant, and actuals inserted as default parameters do not match
8780 -- explicit actuals with the same value.
8782 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8783 -- Compare an operator node with a function call
8789 function FCL (L1, L2 : List_Id) return Boolean is
8793 if L1 = No_List then
8799 if L2 = No_List then
8805 -- Compare two lists, skipping rewrite insertions (we want to compare
8806 -- the original trees, not the expanded versions).
8809 if Is_Rewrite_Insertion (N1) then
8811 elsif Is_Rewrite_Insertion (N2) then
8817 elsif not FCE (N1, N2) then
8830 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8831 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8836 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8841 Act := First (Actuals);
8843 if Nkind (Op_Node) in N_Binary_Op then
8844 if not FCE (Left_Opnd (Op_Node), Act) then
8851 return Present (Act)
8852 and then FCE (Right_Opnd (Op_Node), Act)
8853 and then No (Next (Act));
8857 -- Start of processing for Fully_Conformant_Expressions
8860 -- Nonconformant if paren count does not match. Note: if some idiot
8861 -- complains that we don't do this right for more than 3 levels of
8862 -- parentheses, they will be treated with the respect they deserve.
8864 if Paren_Count (E1) /= Paren_Count (E2) then
8867 -- If same entities are referenced, then they are conformant even if
8868 -- they have different forms (RM 8.3.1(19-20)).
8870 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8871 if Present (Entity (E1)) then
8872 return Entity (E1) = Entity (E2)
8874 -- One may be a discriminant that has been replaced by the
8875 -- corresponding discriminal.
8878 (Chars (Entity (E1)) = Chars (Entity (E2))
8879 and then Ekind (Entity (E1)) = E_Discriminant
8880 and then Ekind (Entity (E2)) = E_In_Parameter)
8882 -- The discriminant of a protected type is transformed into
8883 -- a local constant and then into a parameter of a protected
8887 (Ekind (Entity (E1)) = E_Constant
8888 and then Ekind (Entity (E2)) = E_In_Parameter
8889 and then Present (Discriminal_Link (Entity (E1)))
8890 and then Discriminal_Link (Entity (E1)) =
8891 Discriminal_Link (Entity (E2)))
8893 -- AI12-050: The loop variables of quantified expressions
8894 -- match if they have the same identifier, even though they
8895 -- are different entities.
8898 (Chars (Entity (E1)) = Chars (Entity (E2))
8899 and then Ekind (Entity (E1)) = E_Loop_Parameter
8900 and then Ekind (Entity (E2)) = E_Loop_Parameter);
8902 elsif Nkind (E1) = N_Expanded_Name
8903 and then Nkind (E2) = N_Expanded_Name
8904 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8905 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8907 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8910 -- Identifiers in component associations don't always have
8911 -- entities, but their names must conform.
8913 return Nkind (E1) = N_Identifier
8914 and then Nkind (E2) = N_Identifier
8915 and then Chars (E1) = Chars (E2);
8918 elsif Nkind (E1) = N_Character_Literal
8919 and then Nkind (E2) = N_Expanded_Name
8921 return Nkind (Selector_Name (E2)) = N_Character_Literal
8922 and then Chars (E1) = Chars (Selector_Name (E2));
8924 elsif Nkind (E2) = N_Character_Literal
8925 and then Nkind (E1) = N_Expanded_Name
8927 return Nkind (Selector_Name (E1)) = N_Character_Literal
8928 and then Chars (E2) = Chars (Selector_Name (E1));
8930 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8931 return FCO (E1, E2);
8933 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8934 return FCO (E2, E1);
8936 -- Otherwise we must have the same syntactic entity
8938 elsif Nkind (E1) /= Nkind (E2) then
8941 -- At this point, we specialize by node type
8947 FCL (Expressions (E1), Expressions (E2))
8949 FCL (Component_Associations (E1),
8950 Component_Associations (E2));
8953 if Nkind (Expression (E1)) = N_Qualified_Expression
8955 Nkind (Expression (E2)) = N_Qualified_Expression
8957 return FCE (Expression (E1), Expression (E2));
8959 -- Check that the subtype marks and any constraints
8964 Indic1 : constant Node_Id := Expression (E1);
8965 Indic2 : constant Node_Id := Expression (E2);
8970 if Nkind (Indic1) /= N_Subtype_Indication then
8972 Nkind (Indic2) /= N_Subtype_Indication
8973 and then Entity (Indic1) = Entity (Indic2);
8975 elsif Nkind (Indic2) /= N_Subtype_Indication then
8977 Nkind (Indic1) /= N_Subtype_Indication
8978 and then Entity (Indic1) = Entity (Indic2);
8981 if Entity (Subtype_Mark (Indic1)) /=
8982 Entity (Subtype_Mark (Indic2))
8987 Elt1 := First (Constraints (Constraint (Indic1)));
8988 Elt2 := First (Constraints (Constraint (Indic2)));
8989 while Present (Elt1) and then Present (Elt2) loop
8990 if not FCE (Elt1, Elt2) then
9003 when N_Attribute_Reference =>
9005 Attribute_Name (E1) = Attribute_Name (E2)
9006 and then FCL (Expressions (E1), Expressions (E2));
9010 Entity (E1) = Entity (E2)
9011 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9012 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9014 when N_Membership_Test
9018 FCE (Left_Opnd (E1), Left_Opnd (E2))
9020 FCE (Right_Opnd (E1), Right_Opnd (E2));
9022 when N_Case_Expression =>
9028 if not FCE (Expression (E1), Expression (E2)) then
9032 Alt1 := First (Alternatives (E1));
9033 Alt2 := First (Alternatives (E2));
9035 if Present (Alt1) /= Present (Alt2) then
9037 elsif No (Alt1) then
9041 if not FCE (Expression (Alt1), Expression (Alt2))
9042 or else not FCL (Discrete_Choices (Alt1),
9043 Discrete_Choices (Alt2))
9054 when N_Character_Literal =>
9056 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9058 when N_Component_Association =>
9060 FCL (Choices (E1), Choices (E2))
9062 FCE (Expression (E1), Expression (E2));
9064 when N_Explicit_Dereference =>
9066 FCE (Prefix (E1), Prefix (E2));
9068 when N_Extension_Aggregate =>
9070 FCL (Expressions (E1), Expressions (E2))
9071 and then Null_Record_Present (E1) =
9072 Null_Record_Present (E2)
9073 and then FCL (Component_Associations (E1),
9074 Component_Associations (E2));
9076 when N_Function_Call =>
9078 FCE (Name (E1), Name (E2))
9080 FCL (Parameter_Associations (E1),
9081 Parameter_Associations (E2));
9083 when N_If_Expression =>
9085 FCL (Expressions (E1), Expressions (E2));
9087 when N_Indexed_Component =>
9089 FCE (Prefix (E1), Prefix (E2))
9091 FCL (Expressions (E1), Expressions (E2));
9093 when N_Integer_Literal =>
9094 return (Intval (E1) = Intval (E2));
9099 when N_Operator_Symbol =>
9101 Chars (E1) = Chars (E2);
9103 when N_Others_Choice =>
9106 when N_Parameter_Association =>
9108 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9109 and then FCE (Explicit_Actual_Parameter (E1),
9110 Explicit_Actual_Parameter (E2));
9112 when N_Qualified_Expression
9114 | N_Unchecked_Type_Conversion
9117 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9119 FCE (Expression (E1), Expression (E2));
9121 when N_Quantified_Expression =>
9122 if not FCE (Condition (E1), Condition (E2)) then
9126 if Present (Loop_Parameter_Specification (E1))
9127 and then Present (Loop_Parameter_Specification (E2))
9130 L1 : constant Node_Id :=
9131 Loop_Parameter_Specification (E1);
9132 L2 : constant Node_Id :=
9133 Loop_Parameter_Specification (E2);
9137 Reverse_Present (L1) = Reverse_Present (L2)
9139 FCE (Defining_Identifier (L1),
9140 Defining_Identifier (L2))
9142 FCE (Discrete_Subtype_Definition (L1),
9143 Discrete_Subtype_Definition (L2));
9146 elsif Present (Iterator_Specification (E1))
9147 and then Present (Iterator_Specification (E2))
9150 I1 : constant Node_Id := Iterator_Specification (E1);
9151 I2 : constant Node_Id := Iterator_Specification (E2);
9155 FCE (Defining_Identifier (I1),
9156 Defining_Identifier (I2))
9158 Of_Present (I1) = Of_Present (I2)
9160 Reverse_Present (I1) = Reverse_Present (I2)
9161 and then FCE (Name (I1), Name (I2))
9162 and then FCE (Subtype_Indication (I1),
9163 Subtype_Indication (I2));
9166 -- The quantified expressions used different specifications to
9167 -- walk their respective ranges.
9175 FCE (Low_Bound (E1), Low_Bound (E2))
9177 FCE (High_Bound (E1), High_Bound (E2));
9179 when N_Real_Literal =>
9180 return (Realval (E1) = Realval (E2));
9182 when N_Selected_Component =>
9184 FCE (Prefix (E1), Prefix (E2))
9186 FCE (Selector_Name (E1), Selector_Name (E2));
9190 FCE (Prefix (E1), Prefix (E2))
9192 FCE (Discrete_Range (E1), Discrete_Range (E2));
9194 when N_String_Literal =>
9196 S1 : constant String_Id := Strval (E1);
9197 S2 : constant String_Id := Strval (E2);
9198 L1 : constant Nat := String_Length (S1);
9199 L2 : constant Nat := String_Length (S2);
9206 for J in 1 .. L1 loop
9207 if Get_String_Char (S1, J) /=
9208 Get_String_Char (S2, J)
9220 Entity (E1) = Entity (E2)
9222 FCE (Right_Opnd (E1), Right_Opnd (E2));
9224 -- All other node types cannot appear in this context. Strictly
9225 -- we should raise a fatal internal error. Instead we just ignore
9226 -- the nodes. This means that if anyone makes a mistake in the
9227 -- expander and mucks an expression tree irretrievably, the result
9228 -- will be a failure to detect a (probably very obscure) case
9229 -- of non-conformance, which is better than bombing on some
9230 -- case where two expressions do in fact conform.
9236 end Fully_Conformant_Expressions;
9238 ----------------------------------------
9239 -- Fully_Conformant_Discrete_Subtypes --
9240 ----------------------------------------
9242 function Fully_Conformant_Discrete_Subtypes
9243 (Given_S1 : Node_Id;
9244 Given_S2 : Node_Id) return Boolean
9246 S1 : constant Node_Id := Original_Node (Given_S1);
9247 S2 : constant Node_Id := Original_Node (Given_S2);
9249 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9250 -- Special-case for a bound given by a discriminant, which in the body
9251 -- is replaced with the discriminal of the enclosing type.
9253 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9254 -- Check both bounds
9256 -----------------------
9257 -- Conforming_Bounds --
9258 -----------------------
9260 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9262 if Is_Entity_Name (B1)
9263 and then Is_Entity_Name (B2)
9264 and then Ekind (Entity (B1)) = E_Discriminant
9266 return Chars (B1) = Chars (B2);
9269 return Fully_Conformant_Expressions (B1, B2);
9271 end Conforming_Bounds;
9273 -----------------------
9274 -- Conforming_Ranges --
9275 -----------------------
9277 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9280 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9282 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9283 end Conforming_Ranges;
9285 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9288 if Nkind (S1) /= Nkind (S2) then
9291 elsif Is_Entity_Name (S1) then
9292 return Entity (S1) = Entity (S2);
9294 elsif Nkind (S1) = N_Range then
9295 return Conforming_Ranges (S1, S2);
9297 elsif Nkind (S1) = N_Subtype_Indication then
9299 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9302 (Range_Expression (Constraint (S1)),
9303 Range_Expression (Constraint (S2)));
9307 end Fully_Conformant_Discrete_Subtypes;
9309 --------------------
9310 -- Install_Entity --
9311 --------------------
9313 procedure Install_Entity (E : Entity_Id) is
9314 Prev : constant Entity_Id := Current_Entity (E);
9316 Set_Is_Immediately_Visible (E);
9317 Set_Current_Entity (E);
9318 Set_Homonym (E, Prev);
9321 ---------------------
9322 -- Install_Formals --
9323 ---------------------
9325 procedure Install_Formals (Id : Entity_Id) is
9328 F := First_Formal (Id);
9329 while Present (F) loop
9333 end Install_Formals;
9335 -----------------------------
9336 -- Is_Interface_Conformant --
9337 -----------------------------
9339 function Is_Interface_Conformant
9340 (Tagged_Type : Entity_Id;
9341 Iface_Prim : Entity_Id;
9342 Prim : Entity_Id) return Boolean
9344 -- The operation may in fact be an inherited (implicit) operation
9345 -- rather than the original interface primitive, so retrieve the
9346 -- ultimate ancestor.
9348 Iface : constant Entity_Id :=
9349 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9350 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9352 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9353 -- Return the controlling formal of Prim
9355 ------------------------
9356 -- Controlling_Formal --
9357 ------------------------
9359 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9363 E := First_Entity (Prim);
9364 while Present (E) loop
9365 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9373 end Controlling_Formal;
9377 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9378 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9380 -- Start of processing for Is_Interface_Conformant
9383 pragma Assert (Is_Subprogram (Iface_Prim)
9384 and then Is_Subprogram (Prim)
9385 and then Is_Dispatching_Operation (Iface_Prim)
9386 and then Is_Dispatching_Operation (Prim));
9388 pragma Assert (Is_Interface (Iface)
9389 or else (Present (Alias (Iface_Prim))
9392 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9394 if Prim = Iface_Prim
9395 or else not Is_Subprogram (Prim)
9396 or else Ekind (Prim) /= Ekind (Iface_Prim)
9397 or else not Is_Dispatching_Operation (Prim)
9398 or else Scope (Prim) /= Scope (Tagged_Type)
9400 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9401 or else not Primitive_Names_Match (Iface_Prim, Prim)
9405 -- The mode of the controlling formals must match
9407 elsif Present (Iface_Ctrl_F)
9408 and then Present (Prim_Ctrl_F)
9409 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9413 -- Case of a procedure, or a function whose result type matches the
9414 -- result type of the interface primitive, or a function that has no
9415 -- controlling result (I or access I).
9417 elsif Ekind (Iface_Prim) = E_Procedure
9418 or else Etype (Prim) = Etype (Iface_Prim)
9419 or else not Has_Controlling_Result (Prim)
9421 return Type_Conformant
9422 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9424 -- Case of a function returning an interface, or an access to one. Check
9425 -- that the return types correspond.
9427 elsif Implements_Interface (Typ, Iface) then
9428 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9430 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9435 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9436 Skip_Controlling_Formals => True);
9442 end Is_Interface_Conformant;
9444 ---------------------------------
9445 -- Is_Non_Overriding_Operation --
9446 ---------------------------------
9448 function Is_Non_Overriding_Operation
9449 (Prev_E : Entity_Id;
9450 New_E : Entity_Id) return Boolean
9454 G_Typ : Entity_Id := Empty;
9456 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9457 -- If F_Type is a derived type associated with a generic actual subtype,
9458 -- then return its Generic_Parent_Type attribute, else return Empty.
9460 function Types_Correspond
9461 (P_Type : Entity_Id;
9462 N_Type : Entity_Id) return Boolean;
9463 -- Returns true if and only if the types (or designated types in the
9464 -- case of anonymous access types) are the same or N_Type is derived
9465 -- directly or indirectly from P_Type.
9467 -----------------------------
9468 -- Get_Generic_Parent_Type --
9469 -----------------------------
9471 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9477 if Is_Derived_Type (F_Typ)
9478 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9480 -- The tree must be traversed to determine the parent subtype in
9481 -- the generic unit, which unfortunately isn't always available
9482 -- via semantic attributes. ??? (Note: The use of Original_Node
9483 -- is needed for cases where a full derived type has been
9486 -- If the parent type is a scalar type, the derivation creates
9487 -- an anonymous base type for it, and the source type is its
9490 if Is_Scalar_Type (F_Typ)
9491 and then not Comes_From_Source (F_Typ)
9495 (Original_Node (Parent (First_Subtype (F_Typ))));
9497 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9499 if Nkind (Defn) = N_Derived_Type_Definition then
9500 Indic := Subtype_Indication (Defn);
9502 if Nkind (Indic) = N_Subtype_Indication then
9503 G_Typ := Entity (Subtype_Mark (Indic));
9505 G_Typ := Entity (Indic);
9508 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9509 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9511 return Generic_Parent_Type (Parent (G_Typ));
9517 end Get_Generic_Parent_Type;
9519 ----------------------
9520 -- Types_Correspond --
9521 ----------------------
9523 function Types_Correspond
9524 (P_Type : Entity_Id;
9525 N_Type : Entity_Id) return Boolean
9527 Prev_Type : Entity_Id := Base_Type (P_Type);
9528 New_Type : Entity_Id := Base_Type (N_Type);
9531 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9532 Prev_Type := Designated_Type (Prev_Type);
9535 if Ekind (New_Type) = E_Anonymous_Access_Type then
9536 New_Type := Designated_Type (New_Type);
9539 if Prev_Type = New_Type then
9542 elsif not Is_Class_Wide_Type (New_Type) then
9543 while Etype (New_Type) /= New_Type loop
9544 New_Type := Etype (New_Type);
9546 if New_Type = Prev_Type then
9552 end Types_Correspond;
9554 -- Start of processing for Is_Non_Overriding_Operation
9557 -- In the case where both operations are implicit derived subprograms
9558 -- then neither overrides the other. This can only occur in certain
9559 -- obscure cases (e.g., derivation from homographs created in a generic
9562 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9565 elsif Ekind (Current_Scope) = E_Package
9566 and then Is_Generic_Instance (Current_Scope)
9567 and then In_Private_Part (Current_Scope)
9568 and then Comes_From_Source (New_E)
9570 -- We examine the formals and result type of the inherited operation,
9571 -- to determine whether their type is derived from (the instance of)
9572 -- a generic type. The first such formal or result type is the one
9575 Formal := First_Formal (Prev_E);
9577 while Present (Formal) loop
9578 F_Typ := Base_Type (Etype (Formal));
9580 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9581 F_Typ := Designated_Type (F_Typ);
9584 G_Typ := Get_Generic_Parent_Type (F_Typ);
9585 exit when Present (G_Typ);
9587 Next_Formal (Formal);
9590 -- If the function dispatches on result check the result type
9592 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9593 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9600 -- If the generic type is a private type, then the original operation
9601 -- was not overriding in the generic, because there was no primitive
9602 -- operation to override.
9604 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9605 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9606 N_Formal_Private_Type_Definition
9610 -- The generic parent type is the ancestor of a formal derived
9611 -- type declaration. We need to check whether it has a primitive
9612 -- operation that should be overridden by New_E in the generic.
9616 P_Formal : Entity_Id;
9617 N_Formal : Entity_Id;
9621 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9624 while Present (Prim_Elt) loop
9625 P_Prim := Node (Prim_Elt);
9627 if Chars (P_Prim) = Chars (New_E)
9628 and then Ekind (P_Prim) = Ekind (New_E)
9630 P_Formal := First_Formal (P_Prim);
9631 N_Formal := First_Formal (New_E);
9632 while Present (P_Formal) and then Present (N_Formal) loop
9633 P_Typ := Etype (P_Formal);
9634 N_Typ := Etype (N_Formal);
9636 if not Types_Correspond (P_Typ, N_Typ) then
9640 Next_Entity (P_Formal);
9641 Next_Entity (N_Formal);
9644 -- Found a matching primitive operation belonging to the
9645 -- formal ancestor type, so the new subprogram is
9649 and then No (N_Formal)
9650 and then (Ekind (New_E) /= E_Function
9653 (Etype (P_Prim), Etype (New_E)))
9659 Next_Elmt (Prim_Elt);
9662 -- If no match found, then the new subprogram does not override
9663 -- in the generic (nor in the instance).
9665 -- If the type in question is not abstract, and the subprogram
9666 -- is, this will be an error if the new operation is in the
9667 -- private part of the instance. Emit a warning now, which will
9668 -- make the subsequent error message easier to understand.
9670 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9671 and then Is_Abstract_Subprogram (Prev_E)
9672 and then In_Private_Part (Current_Scope)
9674 Error_Msg_Node_2 := F_Typ;
9676 ("private operation& in generic unit does not override "
9677 & "any primitive operation of& (RM 12.3 (18))??",
9687 end Is_Non_Overriding_Operation;
9689 -------------------------------------
9690 -- List_Inherited_Pre_Post_Aspects --
9691 -------------------------------------
9693 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9695 if Opt.List_Inherited_Aspects
9696 and then Is_Subprogram_Or_Generic_Subprogram (E)
9699 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9704 for Index in Subps'Range loop
9705 Items := Contract (Subps (Index));
9707 if Present (Items) then
9708 Prag := Pre_Post_Conditions (Items);
9709 while Present (Prag) loop
9710 Error_Msg_Sloc := Sloc (Prag);
9712 if Class_Present (Prag)
9713 and then not Split_PPC (Prag)
9715 if Pragma_Name (Prag) = Name_Precondition then
9717 ("info: & inherits `Pre''Class` aspect from "
9721 ("info: & inherits `Post''Class` aspect from "
9726 Prag := Next_Pragma (Prag);
9732 end List_Inherited_Pre_Post_Aspects;
9734 ------------------------------
9735 -- Make_Inequality_Operator --
9736 ------------------------------
9738 -- S is the defining identifier of an equality operator. We build a
9739 -- subprogram declaration with the right signature. This operation is
9740 -- intrinsic, because it is always expanded as the negation of the
9741 -- call to the equality function.
9743 procedure Make_Inequality_Operator (S : Entity_Id) is
9744 Loc : constant Source_Ptr := Sloc (S);
9747 Op_Name : Entity_Id;
9749 FF : constant Entity_Id := First_Formal (S);
9750 NF : constant Entity_Id := Next_Formal (FF);
9753 -- Check that equality was properly defined, ignore call if not
9760 A : constant Entity_Id :=
9761 Make_Defining_Identifier (Sloc (FF),
9762 Chars => Chars (FF));
9764 B : constant Entity_Id :=
9765 Make_Defining_Identifier (Sloc (NF),
9766 Chars => Chars (NF));
9769 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9771 Formals := New_List (
9772 Make_Parameter_Specification (Loc,
9773 Defining_Identifier => A,
9775 New_Occurrence_Of (Etype (First_Formal (S)),
9776 Sloc (Etype (First_Formal (S))))),
9778 Make_Parameter_Specification (Loc,
9779 Defining_Identifier => B,
9781 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9782 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9785 Make_Subprogram_Declaration (Loc,
9787 Make_Function_Specification (Loc,
9788 Defining_Unit_Name => Op_Name,
9789 Parameter_Specifications => Formals,
9790 Result_Definition =>
9791 New_Occurrence_Of (Standard_Boolean, Loc)));
9793 -- Insert inequality right after equality if it is explicit or after
9794 -- the derived type when implicit. These entities are created only
9795 -- for visibility purposes, and eventually replaced in the course
9796 -- of expansion, so they do not need to be attached to the tree and
9797 -- seen by the back-end. Keeping them internal also avoids spurious
9798 -- freezing problems. The declaration is inserted in the tree for
9799 -- analysis, and removed afterwards. If the equality operator comes
9800 -- from an explicit declaration, attach the inequality immediately
9801 -- after. Else the equality is inherited from a derived type
9802 -- declaration, so insert inequality after that declaration.
9804 if No (Alias (S)) then
9805 Insert_After (Unit_Declaration_Node (S), Decl);
9806 elsif Is_List_Member (Parent (S)) then
9807 Insert_After (Parent (S), Decl);
9809 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9812 Mark_Rewrite_Insertion (Decl);
9813 Set_Is_Intrinsic_Subprogram (Op_Name);
9816 Set_Has_Completion (Op_Name);
9817 Set_Corresponding_Equality (Op_Name, S);
9818 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9820 end Make_Inequality_Operator;
9822 ----------------------
9823 -- May_Need_Actuals --
9824 ----------------------
9826 procedure May_Need_Actuals (Fun : Entity_Id) is
9831 F := First_Formal (Fun);
9833 while Present (F) loop
9834 if No (Default_Value (F)) then
9842 Set_Needs_No_Actuals (Fun, B);
9843 end May_Need_Actuals;
9845 ---------------------
9846 -- Mode_Conformant --
9847 ---------------------
9849 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9852 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9854 end Mode_Conformant;
9856 ---------------------------
9857 -- New_Overloaded_Entity --
9858 ---------------------------
9860 procedure New_Overloaded_Entity
9862 Derived_Type : Entity_Id := Empty)
9864 Overridden_Subp : Entity_Id := Empty;
9865 -- Set if the current scope has an operation that is type-conformant
9866 -- with S, and becomes hidden by S.
9868 Is_Primitive_Subp : Boolean;
9869 -- Set to True if the new subprogram is primitive
9872 -- Entity that S overrides
9874 Prev_Vis : Entity_Id := Empty;
9875 -- Predecessor of E in Homonym chain
9877 procedure Check_For_Primitive_Subprogram
9878 (Is_Primitive : out Boolean;
9879 Is_Overriding : Boolean := False);
9880 -- If the subprogram being analyzed is a primitive operation of the type
9881 -- of a formal or result, set the Has_Primitive_Operations flag on the
9882 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9883 -- corresponding flag on the entity itself for later use.
9885 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9886 -- True if a) E is a subprogram whose first formal is a concurrent type
9887 -- defined in the scope of E that has some entry or subprogram whose
9888 -- profile matches E, or b) E is an internally built dispatching
9889 -- subprogram of a protected type and there is a matching subprogram
9890 -- defined in the enclosing scope of the protected type, or c) E is
9891 -- an entry of a synchronized type and a matching procedure has been
9892 -- previously defined in the enclosing scope of the synchronized type.
9894 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9895 -- Check that E is declared in the private part of the current package,
9896 -- or in the package body, where it may hide a previous declaration.
9897 -- We can't use In_Private_Part by itself because this flag is also
9898 -- set when freezing entities, so we must examine the place of the
9899 -- declaration in the tree, and recognize wrapper packages as well.
9901 function Is_Overriding_Alias
9903 New_E : Entity_Id) return Boolean;
9904 -- Check whether new subprogram and old subprogram are both inherited
9905 -- from subprograms that have distinct dispatch table entries. This can
9906 -- occur with derivations from instances with accidental homonyms. The
9907 -- function is conservative given that the converse is only true within
9908 -- instances that contain accidental overloadings.
9910 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9911 -- Report conflict between entities S and E
9913 ------------------------------------
9914 -- Check_For_Primitive_Subprogram --
9915 ------------------------------------
9917 procedure Check_For_Primitive_Subprogram
9918 (Is_Primitive : out Boolean;
9919 Is_Overriding : Boolean := False)
9925 function Visible_Part_Type (T : Entity_Id) return Boolean;
9926 -- Returns true if T is declared in the visible part of the current
9927 -- package scope; otherwise returns false. Assumes that T is declared
9930 procedure Check_Private_Overriding (T : Entity_Id);
9931 -- Checks that if a primitive abstract subprogram of a visible
9932 -- abstract type is declared in a private part, then it must override
9933 -- an abstract subprogram declared in the visible part. Also checks
9934 -- that if a primitive function with a controlling result is declared
9935 -- in a private part, then it must override a function declared in
9936 -- the visible part.
9938 ------------------------------
9939 -- Check_Private_Overriding --
9940 ------------------------------
9942 procedure Check_Private_Overriding (T : Entity_Id) is
9943 function Overrides_Private_Part_Op return Boolean;
9944 -- This detects the special case where the overriding subprogram
9945 -- is overriding a subprogram that was declared in the same
9946 -- private part. That case is illegal by 3.9.3(10).
9948 function Overrides_Visible_Function
9949 (Partial_View : Entity_Id) return Boolean;
9950 -- True if S overrides a function in the visible part. The
9951 -- overridden function could be explicitly or implicitly declared.
9953 -------------------------------
9954 -- Overrides_Private_Part_Op --
9955 -------------------------------
9957 function Overrides_Private_Part_Op return Boolean is
9958 Over_Decl : constant Node_Id :=
9959 Unit_Declaration_Node (Overridden_Operation (S));
9960 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
9963 pragma Assert (Is_Overriding);
9965 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
9967 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
9969 return In_Same_List (Over_Decl, Subp_Decl);
9970 end Overrides_Private_Part_Op;
9972 --------------------------------
9973 -- Overrides_Visible_Function --
9974 --------------------------------
9976 function Overrides_Visible_Function
9977 (Partial_View : Entity_Id) return Boolean
9980 if not Is_Overriding or else not Has_Homonym (S) then
9984 if not Present (Partial_View) then
9988 -- Search through all the homonyms H of S in the current
9989 -- package spec, and return True if we find one that matches.
9990 -- Note that Parent (H) will be the declaration of the
9991 -- partial view of T for a match.
9998 exit when not Present (H) or else Scope (H) /= Scope (S);
10002 N_Private_Extension_Declaration,
10003 N_Private_Type_Declaration)
10004 and then Defining_Identifier (Parent (H)) = Partial_View
10012 end Overrides_Visible_Function;
10014 -- Start of processing for Check_Private_Overriding
10017 if Is_Package_Or_Generic_Package (Current_Scope)
10018 and then In_Private_Part (Current_Scope)
10019 and then Visible_Part_Type (T)
10020 and then not In_Instance
10022 if Is_Abstract_Type (T)
10023 and then Is_Abstract_Subprogram (S)
10024 and then (not Is_Overriding
10025 or else not Is_Abstract_Subprogram (E)
10026 or else Overrides_Private_Part_Op)
10029 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10032 elsif Ekind (S) = E_Function then
10034 Partial_View : constant Entity_Id :=
10035 Incomplete_Or_Partial_View (T);
10038 if not Overrides_Visible_Function (Partial_View) then
10040 -- Here, S is "function ... return T;" declared in
10041 -- the private part, not overriding some visible
10042 -- operation. That's illegal in the tagged case
10043 -- (but not if the private type is untagged).
10045 if ((Present (Partial_View)
10046 and then Is_Tagged_Type (Partial_View))
10047 or else (not Present (Partial_View)
10048 and then Is_Tagged_Type (T)))
10049 and then T = Base_Type (Etype (S))
10052 ("private function with tagged result must"
10053 & " override visible-part function", S);
10055 ("\move subprogram to the visible part"
10056 & " (RM 3.9.3(10))", S);
10058 -- AI05-0073: extend this test to the case of a
10059 -- function with a controlling access result.
10061 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10062 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10064 not Is_Class_Wide_Type
10065 (Designated_Type (Etype (S)))
10066 and then Ada_Version >= Ada_2012
10069 ("private function with controlling access "
10070 & "result must override visible-part function",
10073 ("\move subprogram to the visible part"
10074 & " (RM 3.9.3(10))", S);
10080 end Check_Private_Overriding;
10082 -----------------------
10083 -- Visible_Part_Type --
10084 -----------------------
10086 function Visible_Part_Type (T : Entity_Id) return Boolean is
10087 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10091 -- If the entity is a private type, then it must be declared in a
10094 if Ekind (T) in Private_Kind then
10098 -- Otherwise, we traverse the visible part looking for its
10099 -- corresponding declaration. We cannot use the declaration
10100 -- node directly because in the private part the entity of a
10101 -- private type is the one in the full view, which does not
10102 -- indicate that it is the completion of something visible.
10104 N := First (Visible_Declarations (Specification (P)));
10105 while Present (N) loop
10106 if Nkind (N) = N_Full_Type_Declaration
10107 and then Present (Defining_Identifier (N))
10108 and then T = Defining_Identifier (N)
10112 elsif Nkind_In (N, N_Private_Type_Declaration,
10113 N_Private_Extension_Declaration)
10114 and then Present (Defining_Identifier (N))
10115 and then T = Full_View (Defining_Identifier (N))
10124 end Visible_Part_Type;
10126 -- Start of processing for Check_For_Primitive_Subprogram
10129 Is_Primitive := False;
10131 if not Comes_From_Source (S) then
10134 -- If subprogram is at library level, it is not primitive operation
10136 elsif Current_Scope = Standard_Standard then
10139 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10140 and then not In_Package_Body (Current_Scope))
10141 or else Is_Overriding
10143 -- For function, check return type
10145 if Ekind (S) = E_Function then
10146 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10147 F_Typ := Designated_Type (Etype (S));
10149 F_Typ := Etype (S);
10152 B_Typ := Base_Type (F_Typ);
10154 if Scope (B_Typ) = Current_Scope
10155 and then not Is_Class_Wide_Type (B_Typ)
10156 and then not Is_Generic_Type (B_Typ)
10158 Is_Primitive := True;
10159 Set_Has_Primitive_Operations (B_Typ);
10160 Set_Is_Primitive (S);
10161 Check_Private_Overriding (B_Typ);
10163 -- The Ghost policy in effect at the point of declaration
10164 -- or a tagged type and a primitive operation must match
10165 -- (SPARK RM 6.9(16)).
10167 Check_Ghost_Primitive (S, B_Typ);
10171 -- For all subprograms, check formals
10173 Formal := First_Formal (S);
10174 while Present (Formal) loop
10175 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10176 F_Typ := Designated_Type (Etype (Formal));
10178 F_Typ := Etype (Formal);
10181 B_Typ := Base_Type (F_Typ);
10183 if Ekind (B_Typ) = E_Access_Subtype then
10184 B_Typ := Base_Type (B_Typ);
10187 if Scope (B_Typ) = Current_Scope
10188 and then not Is_Class_Wide_Type (B_Typ)
10189 and then not Is_Generic_Type (B_Typ)
10191 Is_Primitive := True;
10192 Set_Is_Primitive (S);
10193 Set_Has_Primitive_Operations (B_Typ);
10194 Check_Private_Overriding (B_Typ);
10196 -- The Ghost policy in effect at the point of declaration
10197 -- of a tagged type and a primitive operation must match
10198 -- (SPARK RM 6.9(16)).
10200 Check_Ghost_Primitive (S, B_Typ);
10203 Next_Formal (Formal);
10206 -- Special case: An equality function can be redefined for a type
10207 -- occurring in a declarative part, and won't otherwise be treated as
10208 -- a primitive because it doesn't occur in a package spec and doesn't
10209 -- override an inherited subprogram. It's important that we mark it
10210 -- primitive so it can be returned by Collect_Primitive_Operations
10211 -- and be used in composing the equality operation of later types
10212 -- that have a component of the type.
10214 elsif Chars (S) = Name_Op_Eq
10215 and then Etype (S) = Standard_Boolean
10217 B_Typ := Base_Type (Etype (First_Formal (S)));
10219 if Scope (B_Typ) = Current_Scope
10221 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10222 and then not Is_Limited_Type (B_Typ)
10224 Is_Primitive := True;
10225 Set_Is_Primitive (S);
10226 Set_Has_Primitive_Operations (B_Typ);
10227 Check_Private_Overriding (B_Typ);
10229 -- The Ghost policy in effect at the point of declaration of a
10230 -- tagged type and a primitive operation must match
10231 -- (SPARK RM 6.9(16)).
10233 Check_Ghost_Primitive (S, B_Typ);
10236 end Check_For_Primitive_Subprogram;
10238 --------------------------------------
10239 -- Has_Matching_Entry_Or_Subprogram --
10240 --------------------------------------
10242 function Has_Matching_Entry_Or_Subprogram
10243 (E : Entity_Id) return Boolean
10245 function Check_Conforming_Parameters
10246 (E1_Param : Node_Id;
10247 E2_Param : Node_Id) return Boolean;
10248 -- Starting from the given parameters, check that all the parameters
10249 -- of two entries or subprograms are subtype conformant. Used to skip
10250 -- the check on the controlling argument.
10252 function Matching_Entry_Or_Subprogram
10253 (Conc_Typ : Entity_Id;
10254 Subp : Entity_Id) return Entity_Id;
10255 -- Return the first entry or subprogram of the given concurrent type
10256 -- whose name matches the name of Subp and has a profile conformant
10257 -- with Subp; return Empty if not found.
10259 function Matching_Dispatching_Subprogram
10260 (Conc_Typ : Entity_Id;
10261 Ent : Entity_Id) return Entity_Id;
10262 -- Return the first dispatching primitive of Conc_Type defined in the
10263 -- enclosing scope of Conc_Type (i.e. before the full definition of
10264 -- this concurrent type) whose name matches the entry Ent and has a
10265 -- profile conformant with the profile of the corresponding (not yet
10266 -- built) dispatching primitive of Ent; return Empty if not found.
10268 function Matching_Original_Protected_Subprogram
10269 (Prot_Typ : Entity_Id;
10270 Subp : Entity_Id) return Entity_Id;
10271 -- Return the first subprogram defined in the enclosing scope of
10272 -- Prot_Typ (before the full definition of this protected type)
10273 -- whose name matches the original name of Subp and has a profile
10274 -- conformant with the profile of Subp; return Empty if not found.
10276 ---------------------------------
10277 -- Check_Confirming_Parameters --
10278 ---------------------------------
10280 function Check_Conforming_Parameters
10281 (E1_Param : Node_Id;
10282 E2_Param : Node_Id) return Boolean
10284 Param_E1 : Node_Id := E1_Param;
10285 Param_E2 : Node_Id := E2_Param;
10288 while Present (Param_E1) and then Present (Param_E2) loop
10289 if Ekind (Defining_Identifier (Param_E1)) /=
10290 Ekind (Defining_Identifier (Param_E2))
10293 (Find_Parameter_Type (Param_E1),
10294 Find_Parameter_Type (Param_E2),
10295 Subtype_Conformant)
10304 -- The candidate is not valid if one of the two lists contains
10305 -- more parameters than the other
10307 return No (Param_E1) and then No (Param_E2);
10308 end Check_Conforming_Parameters;
10310 ----------------------------------
10311 -- Matching_Entry_Or_Subprogram --
10312 ----------------------------------
10314 function Matching_Entry_Or_Subprogram
10315 (Conc_Typ : Entity_Id;
10316 Subp : Entity_Id) return Entity_Id
10321 E := First_Entity (Conc_Typ);
10322 while Present (E) loop
10323 if Chars (Subp) = Chars (E)
10324 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10326 Check_Conforming_Parameters
10327 (First (Parameter_Specifications (Parent (E))),
10328 Next (First (Parameter_Specifications (Parent (Subp)))))
10337 end Matching_Entry_Or_Subprogram;
10339 -------------------------------------
10340 -- Matching_Dispatching_Subprogram --
10341 -------------------------------------
10343 function Matching_Dispatching_Subprogram
10344 (Conc_Typ : Entity_Id;
10345 Ent : Entity_Id) return Entity_Id
10350 -- Search for entities in the enclosing scope of this synchonized
10353 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10354 Push_Scope (Scope (Conc_Typ));
10355 E := Current_Entity_In_Scope (Ent);
10358 while Present (E) loop
10359 if Scope (E) = Scope (Conc_Typ)
10360 and then Comes_From_Source (E)
10361 and then Ekind (E) = E_Procedure
10362 and then Present (First_Entity (E))
10363 and then Is_Controlling_Formal (First_Entity (E))
10364 and then Etype (First_Entity (E)) = Conc_Typ
10366 Check_Conforming_Parameters
10367 (First (Parameter_Specifications (Parent (Ent))),
10368 Next (First (Parameter_Specifications (Parent (E)))))
10377 end Matching_Dispatching_Subprogram;
10379 --------------------------------------------
10380 -- Matching_Original_Protected_Subprogram --
10381 --------------------------------------------
10383 function Matching_Original_Protected_Subprogram
10384 (Prot_Typ : Entity_Id;
10385 Subp : Entity_Id) return Entity_Id
10387 ICF : constant Boolean :=
10388 Is_Controlling_Formal (First_Entity (Subp));
10392 -- Temporarily decorate the first parameter of Subp as controlling
10393 -- formal, required to invoke Subtype_Conformant.
10395 Set_Is_Controlling_Formal (First_Entity (Subp));
10398 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10400 while Present (E) loop
10401 if Scope (E) = Scope (Prot_Typ)
10402 and then Comes_From_Source (E)
10403 and then Ekind (Subp) = Ekind (E)
10404 and then Present (First_Entity (E))
10405 and then Is_Controlling_Formal (First_Entity (E))
10406 and then Etype (First_Entity (E)) = Prot_Typ
10407 and then Subtype_Conformant (Subp, E,
10408 Skip_Controlling_Formals => True)
10410 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10417 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10420 end Matching_Original_Protected_Subprogram;
10422 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10425 -- Case 1: E is a subprogram whose first formal is a concurrent type
10426 -- defined in the scope of E that has an entry or subprogram whose
10427 -- profile matches E.
10429 if Comes_From_Source (E)
10430 and then Is_Subprogram (E)
10431 and then Present (First_Entity (E))
10432 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10435 Scope (Corresponding_Concurrent_Type
10436 (Etype (First_Entity (E))))
10439 (Matching_Entry_Or_Subprogram
10440 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10443 Report_Conflict (E,
10444 Matching_Entry_Or_Subprogram
10445 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10450 -- Case 2: E is an internally built dispatching subprogram of a
10451 -- protected type and there is a subprogram defined in the enclosing
10452 -- scope of the protected type that has the original name of E and
10453 -- its profile is conformant with the profile of E. We check the
10454 -- name of the original protected subprogram associated with E since
10455 -- the expander builds dispatching primitives of protected functions
10456 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10458 elsif not Comes_From_Source (E)
10459 and then Is_Subprogram (E)
10460 and then Present (First_Entity (E))
10461 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10462 and then Present (Original_Protected_Subprogram (E))
10465 (Matching_Original_Protected_Subprogram
10466 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10469 Report_Conflict (E,
10470 Matching_Original_Protected_Subprogram
10471 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10475 -- Case 3: E is an entry of a synchronized type and a matching
10476 -- procedure has been previously defined in the enclosing scope
10477 -- of the synchronized type.
10479 elsif Comes_From_Source (E)
10480 and then Ekind (E) = E_Entry
10482 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10484 Report_Conflict (E,
10485 Matching_Dispatching_Subprogram (Current_Scope, E));
10490 end Has_Matching_Entry_Or_Subprogram;
10492 ----------------------------
10493 -- Is_Private_Declaration --
10494 ----------------------------
10496 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10497 Decl : constant Node_Id := Unit_Declaration_Node (E);
10498 Priv_Decls : List_Id;
10501 if Is_Package_Or_Generic_Package (Current_Scope)
10502 and then In_Private_Part (Current_Scope)
10505 Private_Declarations (Package_Specification (Current_Scope));
10507 return In_Package_Body (Current_Scope)
10509 (Is_List_Member (Decl)
10510 and then List_Containing (Decl) = Priv_Decls)
10511 or else (Nkind (Parent (Decl)) = N_Package_Specification
10513 Is_Compilation_Unit
10514 (Defining_Entity (Parent (Decl)))
10515 and then List_Containing (Parent (Parent (Decl))) =
10520 end Is_Private_Declaration;
10522 --------------------------
10523 -- Is_Overriding_Alias --
10524 --------------------------
10526 function Is_Overriding_Alias
10527 (Old_E : Entity_Id;
10528 New_E : Entity_Id) return Boolean
10530 AO : constant Entity_Id := Alias (Old_E);
10531 AN : constant Entity_Id := Alias (New_E);
10534 return Scope (AO) /= Scope (AN)
10535 or else No (DTC_Entity (AO))
10536 or else No (DTC_Entity (AN))
10537 or else DT_Position (AO) = DT_Position (AN);
10538 end Is_Overriding_Alias;
10540 ---------------------
10541 -- Report_Conflict --
10542 ---------------------
10544 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10546 Error_Msg_Sloc := Sloc (E);
10548 -- Generate message, with useful additional warning if in generic
10550 if Is_Generic_Unit (E) then
10551 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10552 Error_Msg_N ("\& conflicts with declaration#", S);
10554 Error_Msg_N ("& conflicts with declaration#", S);
10556 end Report_Conflict;
10558 -- Start of processing for New_Overloaded_Entity
10561 -- We need to look for an entity that S may override. This must be a
10562 -- homonym in the current scope, so we look for the first homonym of
10563 -- S in the current scope as the starting point for the search.
10565 E := Current_Entity_In_Scope (S);
10567 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10568 -- They are directly added to the list of primitive operations of
10569 -- Derived_Type, unless this is a rederivation in the private part
10570 -- of an operation that was already derived in the visible part of
10571 -- the current package.
10573 if Ada_Version >= Ada_2005
10574 and then Present (Derived_Type)
10575 and then Present (Alias (S))
10576 and then Is_Dispatching_Operation (Alias (S))
10577 and then Present (Find_Dispatching_Type (Alias (S)))
10578 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10580 -- For private types, when the full-view is processed we propagate to
10581 -- the full view the non-overridden entities whose attribute "alias"
10582 -- references an interface primitive. These entities were added by
10583 -- Derive_Subprograms to ensure that interface primitives are
10586 -- Inside_Freeze_Actions is non zero when S corresponds with an
10587 -- internal entity that links an interface primitive with its
10588 -- covering primitive through attribute Interface_Alias (see
10589 -- Add_Internal_Interface_Entities).
10591 if Inside_Freezing_Actions = 0
10592 and then Is_Package_Or_Generic_Package (Current_Scope)
10593 and then In_Private_Part (Current_Scope)
10594 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10595 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10596 and then Full_View (Defining_Identifier (Parent (E)))
10597 = Defining_Identifier (Parent (S))
10598 and then Alias (E) = Alias (S)
10600 Check_Operation_From_Private_View (S, E);
10601 Set_Is_Dispatching_Operation (S);
10606 Enter_Overloaded_Entity (S);
10607 Check_Dispatching_Operation (S, Empty);
10608 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10614 -- For synchronized types check conflicts of this entity with previously
10615 -- defined entities.
10617 if Ada_Version >= Ada_2005
10618 and then Has_Matching_Entry_Or_Subprogram (S)
10623 -- If there is no homonym then this is definitely not overriding
10626 Enter_Overloaded_Entity (S);
10627 Check_Dispatching_Operation (S, Empty);
10628 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10630 -- If subprogram has an explicit declaration, check whether it has an
10631 -- overriding indicator.
10633 if Comes_From_Source (S) then
10634 Check_Synchronized_Overriding (S, Overridden_Subp);
10636 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10637 -- it may have overridden some hidden inherited primitive. Update
10638 -- Overridden_Subp to avoid spurious errors when checking the
10639 -- overriding indicator.
10641 if Ada_Version >= Ada_2012
10642 and then No (Overridden_Subp)
10643 and then Is_Dispatching_Operation (S)
10644 and then Present (Overridden_Operation (S))
10646 Overridden_Subp := Overridden_Operation (S);
10649 Check_Overriding_Indicator
10650 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10652 -- The Ghost policy in effect at the point of declaration of a
10653 -- parent subprogram and an overriding subprogram must match
10654 -- (SPARK RM 6.9(17)).
10656 Check_Ghost_Overriding (S, Overridden_Subp);
10659 -- If there is a homonym that is not overloadable, then we have an
10660 -- error, except for the special cases checked explicitly below.
10662 elsif not Is_Overloadable (E) then
10664 -- Check for spurious conflict produced by a subprogram that has the
10665 -- same name as that of the enclosing generic package. The conflict
10666 -- occurs within an instance, between the subprogram and the renaming
10667 -- declaration for the package. After the subprogram, the package
10668 -- renaming declaration becomes hidden.
10670 if Ekind (E) = E_Package
10671 and then Present (Renamed_Object (E))
10672 and then Renamed_Object (E) = Current_Scope
10673 and then Nkind (Parent (Renamed_Object (E))) =
10674 N_Package_Specification
10675 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10678 Set_Is_Immediately_Visible (E, False);
10679 Enter_Overloaded_Entity (S);
10680 Set_Homonym (S, Homonym (E));
10681 Check_Dispatching_Operation (S, Empty);
10682 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10684 -- If the subprogram is implicit it is hidden by the previous
10685 -- declaration. However if it is dispatching, it must appear in the
10686 -- dispatch table anyway, because it can be dispatched to even if it
10687 -- cannot be called directly.
10689 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10690 Set_Scope (S, Current_Scope);
10692 if Is_Dispatching_Operation (Alias (S)) then
10693 Check_Dispatching_Operation (S, Empty);
10699 Report_Conflict (S, E);
10703 -- E exists and is overloadable
10706 Check_Synchronized_Overriding (S, Overridden_Subp);
10708 -- Loop through E and its homonyms to determine if any of them is
10709 -- the candidate for overriding by S.
10711 while Present (E) loop
10713 -- Definitely not interesting if not in the current scope
10715 if Scope (E) /= Current_Scope then
10718 -- A function can overload the name of an abstract state. The
10719 -- state can be viewed as a function with a profile that cannot
10720 -- be matched by anything.
10722 elsif Ekind (S) = E_Function
10723 and then Ekind (E) = E_Abstract_State
10725 Enter_Overloaded_Entity (S);
10728 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10729 -- procedures locate the internally generated spec. We enforce
10730 -- mode conformance since a tagged type may inherit from
10731 -- interfaces several null primitives which differ only in
10732 -- the mode of the formals.
10734 elsif not Comes_From_Source (S)
10735 and then Is_Null_Procedure (S)
10736 and then not Mode_Conformant (E, S)
10740 -- Check if we have type conformance
10742 elsif Type_Conformant (E, S) then
10744 -- If the old and new entities have the same profile and one
10745 -- is not the body of the other, then this is an error, unless
10746 -- one of them is implicitly declared.
10748 -- There are some cases when both can be implicit, for example
10749 -- when both a literal and a function that overrides it are
10750 -- inherited in a derivation, or when an inherited operation
10751 -- of a tagged full type overrides the inherited operation of
10752 -- a private extension. Ada 83 had a special rule for the
10753 -- literal case. In Ada 95, the later implicit operation hides
10754 -- the former, and the literal is always the former. In the
10755 -- odd case where both are derived operations declared at the
10756 -- same point, both operations should be declared, and in that
10757 -- case we bypass the following test and proceed to the next
10758 -- part. This can only occur for certain obscure cases in
10759 -- instances, when an operation on a type derived from a formal
10760 -- private type does not override a homograph inherited from
10761 -- the actual. In subsequent derivations of such a type, the
10762 -- DT positions of these operations remain distinct, if they
10765 if Present (Alias (S))
10766 and then (No (Alias (E))
10767 or else Comes_From_Source (E)
10768 or else Is_Abstract_Subprogram (S)
10770 (Is_Dispatching_Operation (E)
10771 and then Is_Overriding_Alias (E, S)))
10772 and then Ekind (E) /= E_Enumeration_Literal
10774 -- When an derived operation is overloaded it may be due to
10775 -- the fact that the full view of a private extension
10776 -- re-inherits. It has to be dealt with.
10778 if Is_Package_Or_Generic_Package (Current_Scope)
10779 and then In_Private_Part (Current_Scope)
10781 Check_Operation_From_Private_View (S, E);
10784 -- In any case the implicit operation remains hidden by the
10785 -- existing declaration, which is overriding. Indicate that
10786 -- E overrides the operation from which S is inherited.
10788 if Present (Alias (S)) then
10789 Set_Overridden_Operation (E, Alias (S));
10790 Inherit_Subprogram_Contract (E, Alias (S));
10793 Set_Overridden_Operation (E, S);
10794 Inherit_Subprogram_Contract (E, S);
10797 if Comes_From_Source (E) then
10798 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10800 -- The Ghost policy in effect at the point of declaration
10801 -- of a parent subprogram and an overriding subprogram
10802 -- must match (SPARK RM 6.9(17)).
10804 Check_Ghost_Overriding (E, S);
10809 -- Within an instance, the renaming declarations for actual
10810 -- subprograms may become ambiguous, but they do not hide each
10813 elsif Ekind (E) /= E_Entry
10814 and then not Comes_From_Source (E)
10815 and then not Is_Generic_Instance (E)
10816 and then (Present (Alias (E))
10817 or else Is_Intrinsic_Subprogram (E))
10818 and then (not In_Instance
10819 or else No (Parent (E))
10820 or else Nkind (Unit_Declaration_Node (E)) /=
10821 N_Subprogram_Renaming_Declaration)
10823 -- A subprogram child unit is not allowed to override an
10824 -- inherited subprogram (10.1.1(20)).
10826 if Is_Child_Unit (S) then
10828 ("child unit overrides inherited subprogram in parent",
10833 if Is_Non_Overriding_Operation (E, S) then
10834 Enter_Overloaded_Entity (S);
10836 if No (Derived_Type)
10837 or else Is_Tagged_Type (Derived_Type)
10839 Check_Dispatching_Operation (S, Empty);
10845 -- E is a derived operation or an internal operator which
10846 -- is being overridden. Remove E from further visibility.
10847 -- Furthermore, if E is a dispatching operation, it must be
10848 -- replaced in the list of primitive operations of its type
10849 -- (see Override_Dispatching_Operation).
10851 Overridden_Subp := E;
10857 Prev := First_Entity (Current_Scope);
10858 while Present (Prev) and then Next_Entity (Prev) /= E loop
10859 Next_Entity (Prev);
10862 -- It is possible for E to be in the current scope and
10863 -- yet not in the entity chain. This can only occur in a
10864 -- generic context where E is an implicit concatenation
10865 -- in the formal part, because in a generic body the
10866 -- entity chain starts with the formals.
10868 -- In GNATprove mode, a wrapper for an operation with
10869 -- axiomatization may be a homonym of another declaration
10870 -- for an actual subprogram (needs refinement ???).
10874 and then GNATprove_Mode
10876 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10877 N_Subprogram_Renaming_Declaration
10881 pragma Assert (Chars (E) = Name_Op_Concat);
10886 -- E must be removed both from the entity_list of the
10887 -- current scope, and from the visibility chain.
10889 if Debug_Flag_E then
10890 Write_Str ("Override implicit operation ");
10891 Write_Int (Int (E));
10895 -- If E is a predefined concatenation, it stands for four
10896 -- different operations. As a result, a single explicit
10897 -- declaration does not hide it. In a possible ambiguous
10898 -- situation, Disambiguate chooses the user-defined op,
10899 -- so it is correct to retain the previous internal one.
10901 if Chars (E) /= Name_Op_Concat
10902 or else Ekind (E) /= E_Operator
10904 -- For nondispatching derived operations that are
10905 -- overridden by a subprogram declared in the private
10906 -- part of a package, we retain the derived subprogram
10907 -- but mark it as not immediately visible. If the
10908 -- derived operation was declared in the visible part
10909 -- then this ensures that it will still be visible
10910 -- outside the package with the proper signature
10911 -- (calls from outside must also be directed to this
10912 -- version rather than the overriding one, unlike the
10913 -- dispatching case). Calls from inside the package
10914 -- will still resolve to the overriding subprogram
10915 -- since the derived one is marked as not visible
10916 -- within the package.
10918 -- If the private operation is dispatching, we achieve
10919 -- the overriding by keeping the implicit operation
10920 -- but setting its alias to be the overriding one. In
10921 -- this fashion the proper body is executed in all
10922 -- cases, but the original signature is used outside
10925 -- If the overriding is not in the private part, we
10926 -- remove the implicit operation altogether.
10928 if Is_Private_Declaration (S) then
10929 if not Is_Dispatching_Operation (E) then
10930 Set_Is_Immediately_Visible (E, False);
10932 -- Work done in Override_Dispatching_Operation,
10933 -- so nothing else needs to be done here.
10939 -- Find predecessor of E in Homonym chain
10941 if E = Current_Entity (E) then
10944 Prev_Vis := Current_Entity (E);
10945 while Homonym (Prev_Vis) /= E loop
10946 Prev_Vis := Homonym (Prev_Vis);
10950 if Prev_Vis /= Empty then
10952 -- Skip E in the visibility chain
10954 Set_Homonym (Prev_Vis, Homonym (E));
10957 Set_Name_Entity_Id (Chars (E), Homonym (E));
10960 Set_Next_Entity (Prev, Next_Entity (E));
10962 if No (Next_Entity (Prev)) then
10963 Set_Last_Entity (Current_Scope, Prev);
10968 Enter_Overloaded_Entity (S);
10970 -- For entities generated by Derive_Subprograms the
10971 -- overridden operation is the inherited primitive
10972 -- (which is available through the attribute alias).
10974 if not (Comes_From_Source (E))
10975 and then Is_Dispatching_Operation (E)
10976 and then Find_Dispatching_Type (E) =
10977 Find_Dispatching_Type (S)
10978 and then Present (Alias (E))
10979 and then Comes_From_Source (Alias (E))
10981 Set_Overridden_Operation (S, Alias (E));
10982 Inherit_Subprogram_Contract (S, Alias (E));
10984 -- Normal case of setting entity as overridden
10986 -- Note: Static_Initialization and Overridden_Operation
10987 -- attributes use the same field in subprogram entities.
10988 -- Static_Initialization is only defined for internal
10989 -- initialization procedures, where Overridden_Operation
10990 -- is irrelevant. Therefore the setting of this attribute
10991 -- must check whether the target is an init_proc.
10993 elsif not Is_Init_Proc (S) then
10994 Set_Overridden_Operation (S, E);
10995 Inherit_Subprogram_Contract (S, E);
10998 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11000 -- The Ghost policy in effect at the point of declaration
11001 -- of a parent subprogram and an overriding subprogram
11002 -- must match (SPARK RM 6.9(17)).
11004 Check_Ghost_Overriding (S, E);
11006 -- If S is a user-defined subprogram or a null procedure
11007 -- expanded to override an inherited null procedure, or a
11008 -- predefined dispatching primitive then indicate that E
11009 -- overrides the operation from which S is inherited.
11011 if Comes_From_Source (S)
11013 (Present (Parent (S))
11015 Nkind (Parent (S)) = N_Procedure_Specification
11017 Null_Present (Parent (S)))
11019 (Present (Alias (E))
11021 Is_Predefined_Dispatching_Operation (Alias (E)))
11023 if Present (Alias (E)) then
11024 Set_Overridden_Operation (S, Alias (E));
11025 Inherit_Subprogram_Contract (S, Alias (E));
11029 if Is_Dispatching_Operation (E) then
11031 -- An overriding dispatching subprogram inherits the
11032 -- convention of the overridden subprogram (AI-117).
11034 Set_Convention (S, Convention (E));
11035 Check_Dispatching_Operation (S, E);
11038 Check_Dispatching_Operation (S, Empty);
11041 Check_For_Primitive_Subprogram
11042 (Is_Primitive_Subp, Is_Overriding => True);
11043 goto Check_Inequality;
11046 -- Apparent redeclarations in instances can occur when two
11047 -- formal types get the same actual type. The subprograms in
11048 -- in the instance are legal, even if not callable from the
11049 -- outside. Calls from within are disambiguated elsewhere.
11050 -- For dispatching operations in the visible part, the usual
11051 -- rules apply, and operations with the same profile are not
11052 -- legal (B830001).
11054 elsif (In_Instance_Visible_Part
11055 and then not Is_Dispatching_Operation (E))
11056 or else In_Instance_Not_Visible
11060 -- Here we have a real error (identical profile)
11063 Error_Msg_Sloc := Sloc (E);
11065 -- Avoid cascaded errors if the entity appears in
11066 -- subsequent calls.
11068 Set_Scope (S, Current_Scope);
11070 -- Generate error, with extra useful warning for the case
11071 -- of a generic instance with no completion.
11073 if Is_Generic_Instance (S)
11074 and then not Has_Completion (E)
11077 ("instantiation cannot provide body for&", S);
11078 Error_Msg_N ("\& conflicts with declaration#", S);
11080 Error_Msg_N ("& conflicts with declaration#", S);
11087 -- If one subprogram has an access parameter and the other
11088 -- a parameter of an access type, calls to either might be
11089 -- ambiguous. Verify that parameters match except for the
11090 -- access parameter.
11092 if May_Hide_Profile then
11098 F1 := First_Formal (S);
11099 F2 := First_Formal (E);
11100 while Present (F1) and then Present (F2) loop
11101 if Is_Access_Type (Etype (F1)) then
11102 if not Is_Access_Type (Etype (F2))
11103 or else not Conforming_Types
11104 (Designated_Type (Etype (F1)),
11105 Designated_Type (Etype (F2)),
11108 May_Hide_Profile := False;
11112 not Conforming_Types
11113 (Etype (F1), Etype (F2), Type_Conformant)
11115 May_Hide_Profile := False;
11122 if May_Hide_Profile
11126 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11135 -- On exit, we know that S is a new entity
11137 Enter_Overloaded_Entity (S);
11138 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11139 Check_Overriding_Indicator
11140 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11142 -- The Ghost policy in effect at the point of declaration of a parent
11143 -- subprogram and an overriding subprogram must match
11144 -- (SPARK RM 6.9(17)).
11146 Check_Ghost_Overriding (S, Overridden_Subp);
11148 -- Overloading is not allowed in SPARK, except for operators
11150 if Nkind (S) /= N_Defining_Operator_Symbol then
11151 Error_Msg_Sloc := Sloc (Homonym (S));
11152 Check_SPARK_05_Restriction
11153 ("overloading not allowed with entity#", S);
11156 -- If S is a derived operation for an untagged type then by
11157 -- definition it's not a dispatching operation (even if the parent
11158 -- operation was dispatching), so Check_Dispatching_Operation is not
11159 -- called in that case.
11161 if No (Derived_Type)
11162 or else Is_Tagged_Type (Derived_Type)
11164 Check_Dispatching_Operation (S, Empty);
11168 -- If this is a user-defined equality operator that is not a derived
11169 -- subprogram, create the corresponding inequality. If the operation is
11170 -- dispatching, the expansion is done elsewhere, and we do not create
11171 -- an explicit inequality operation.
11173 <<Check_Inequality>>
11174 if Chars (S) = Name_Op_Eq
11175 and then Etype (S) = Standard_Boolean
11176 and then Present (Parent (S))
11177 and then not Is_Dispatching_Operation (S)
11179 Make_Inequality_Operator (S);
11180 Check_Untagged_Equality (S);
11182 end New_Overloaded_Entity;
11184 ---------------------
11185 -- Process_Formals --
11186 ---------------------
11188 procedure Process_Formals
11190 Related_Nod : Node_Id)
11192 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11193 -- Determine whether an access type designates a type coming from a
11196 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11197 -- Check whether the default has a class-wide type. After analysis the
11198 -- default has the type of the formal, so we must also check explicitly
11199 -- for an access attribute.
11201 ----------------------------------
11202 -- Designates_From_Limited_With --
11203 ----------------------------------
11205 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11206 Desig : Entity_Id := Typ;
11209 if Is_Access_Type (Desig) then
11210 Desig := Directly_Designated_Type (Desig);
11213 if Is_Class_Wide_Type (Desig) then
11214 Desig := Root_Type (Desig);
11218 Ekind (Desig) = E_Incomplete_Type
11219 and then From_Limited_With (Desig);
11220 end Designates_From_Limited_With;
11222 ---------------------------
11223 -- Is_Class_Wide_Default --
11224 ---------------------------
11226 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11228 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11229 or else (Nkind (D) = N_Attribute_Reference
11230 and then Attribute_Name (D) = Name_Access
11231 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11232 end Is_Class_Wide_Default;
11236 Context : constant Node_Id := Parent (Parent (T));
11238 Formal : Entity_Id;
11239 Formal_Type : Entity_Id;
11240 Param_Spec : Node_Id;
11243 Num_Out_Params : Nat := 0;
11244 First_Out_Param : Entity_Id := Empty;
11245 -- Used for setting Is_Only_Out_Parameter
11247 -- Start of processing for Process_Formals
11250 -- In order to prevent premature use of the formals in the same formal
11251 -- part, the Ekind is left undefined until all default expressions are
11252 -- analyzed. The Ekind is established in a separate loop at the end.
11254 Param_Spec := First (T);
11255 while Present (Param_Spec) loop
11256 Formal := Defining_Identifier (Param_Spec);
11257 Set_Never_Set_In_Source (Formal, True);
11258 Enter_Name (Formal);
11260 -- Case of ordinary parameters
11262 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11263 Find_Type (Parameter_Type (Param_Spec));
11264 Ptype := Parameter_Type (Param_Spec);
11266 if Ptype = Error then
11270 Formal_Type := Entity (Ptype);
11272 if Is_Incomplete_Type (Formal_Type)
11274 (Is_Class_Wide_Type (Formal_Type)
11275 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11277 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11278 -- primitive operations, as long as their completion is
11279 -- in the same declarative part. If in the private part
11280 -- this means that the type cannot be a Taft-amendment type.
11281 -- Check is done on package exit. For access to subprograms,
11282 -- the use is legal for Taft-amendment types.
11284 -- Ada 2012: tagged incomplete types are allowed as generic
11285 -- formal types. They do not introduce dependencies and the
11286 -- corresponding generic subprogram does not have a delayed
11287 -- freeze, because it does not need a freeze node. However,
11288 -- it is still the case that untagged incomplete types cannot
11289 -- be Taft-amendment types and must be completed in private
11290 -- part, so the subprogram must appear in the list of private
11291 -- dependents of the type.
11293 if Is_Tagged_Type (Formal_Type)
11294 or else (Ada_Version >= Ada_2012
11295 and then not From_Limited_With (Formal_Type)
11296 and then not Is_Generic_Type (Formal_Type))
11298 if Ekind (Scope (Current_Scope)) = E_Package
11299 and then not Is_Generic_Type (Formal_Type)
11300 and then not Is_Class_Wide_Type (Formal_Type)
11303 (Parent (T), N_Access_Function_Definition,
11304 N_Access_Procedure_Definition)
11306 Append_Elmt (Current_Scope,
11307 Private_Dependents (Base_Type (Formal_Type)));
11309 -- Freezing is delayed to ensure that Register_Prim
11310 -- will get called for this operation, which is needed
11311 -- in cases where static dispatch tables aren't built.
11312 -- (Note that the same is done for controlling access
11313 -- parameter cases in function Access_Definition.)
11315 if not Is_Thunk (Current_Scope) then
11316 Set_Has_Delayed_Freeze (Current_Scope);
11321 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11322 N_Access_Procedure_Definition)
11324 -- AI05-0151: Tagged incomplete types are allowed in all
11325 -- formal parts. Untagged incomplete types are not allowed
11326 -- in bodies. Limited views of either kind are not allowed
11327 -- if there is no place at which the non-limited view can
11328 -- become available.
11330 -- Incomplete formal untagged types are not allowed in
11331 -- subprogram bodies (but are legal in their declarations).
11332 -- This excludes bodies created for null procedures, which
11333 -- are basic declarations.
11335 if Is_Generic_Type (Formal_Type)
11336 and then not Is_Tagged_Type (Formal_Type)
11337 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11340 ("invalid use of formal incomplete type", Param_Spec);
11342 elsif Ada_Version >= Ada_2012 then
11343 if Is_Tagged_Type (Formal_Type)
11344 and then (not From_Limited_With (Formal_Type)
11345 or else not In_Package_Body)
11349 elsif Nkind_In (Context, N_Accept_Statement,
11350 N_Accept_Alternative,
11352 or else (Nkind (Context) = N_Subprogram_Body
11353 and then Comes_From_Source (Context))
11356 ("invalid use of untagged incomplete type &",
11357 Ptype, Formal_Type);
11362 ("invalid use of incomplete type&",
11363 Param_Spec, Formal_Type);
11365 -- Further checks on the legality of incomplete types
11366 -- in formal parts are delayed until the freeze point
11367 -- of the enclosing subprogram or access to subprogram.
11371 elsif Ekind (Formal_Type) = E_Void then
11373 ("premature use of&",
11374 Parameter_Type (Param_Spec), Formal_Type);
11377 -- Ada 2012 (AI-142): Handle aliased parameters
11379 if Ada_Version >= Ada_2012
11380 and then Aliased_Present (Param_Spec)
11382 Set_Is_Aliased (Formal);
11385 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11386 -- declaration corresponding to the null-excluding type of the
11387 -- formal in the enclosing scope. Finally, replace the parameter
11388 -- type of the formal with the internal subtype.
11390 if Ada_Version >= Ada_2005
11391 and then Null_Exclusion_Present (Param_Spec)
11393 if not Is_Access_Type (Formal_Type) then
11395 ("`NOT NULL` allowed only for an access type", Param_Spec);
11398 if Can_Never_Be_Null (Formal_Type)
11399 and then Comes_From_Source (Related_Nod)
11402 ("`NOT NULL` not allowed (& already excludes null)",
11403 Param_Spec, Formal_Type);
11407 Create_Null_Excluding_Itype
11409 Related_Nod => Related_Nod,
11410 Scope_Id => Scope (Current_Scope));
11412 -- If the designated type of the itype is an itype that is
11413 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11414 -- on the access subtype, to prevent order-of-elaboration
11415 -- issues in the backend.
11418 -- type T is access procedure;
11419 -- procedure Op (O : not null T);
11421 if Is_Itype (Directly_Designated_Type (Formal_Type))
11423 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11425 Set_Has_Delayed_Freeze (Formal_Type);
11430 -- An access formal type
11434 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11436 -- No need to continue if we already notified errors
11438 if not Present (Formal_Type) then
11442 -- Ada 2005 (AI-254)
11445 AD : constant Node_Id :=
11446 Access_To_Subprogram_Definition
11447 (Parameter_Type (Param_Spec));
11449 if Present (AD) and then Protected_Present (AD) then
11451 Replace_Anonymous_Access_To_Protected_Subprogram
11457 Set_Etype (Formal, Formal_Type);
11459 -- Deal with default expression if present
11461 Default := Expression (Param_Spec);
11463 if Present (Default) then
11464 Check_SPARK_05_Restriction
11465 ("default expression is not allowed", Default);
11467 if Out_Present (Param_Spec) then
11469 ("default initialization only allowed for IN parameters",
11473 -- Do the special preanalysis of the expression (see section on
11474 -- "Handling of Default Expressions" in the spec of package Sem).
11476 Preanalyze_Spec_Expression (Default, Formal_Type);
11478 -- An access to constant cannot be the default for
11479 -- an access parameter that is an access to variable.
11481 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11482 and then not Is_Access_Constant (Formal_Type)
11483 and then Is_Access_Type (Etype (Default))
11484 and then Is_Access_Constant (Etype (Default))
11487 ("formal that is access to variable cannot be initialized "
11488 & "with an access-to-constant expression", Default);
11491 -- Check that the designated type of an access parameter's default
11492 -- is not a class-wide type unless the parameter's designated type
11493 -- is also class-wide.
11495 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11496 and then not Designates_From_Limited_With (Formal_Type)
11497 and then Is_Class_Wide_Default (Default)
11498 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11501 ("access to class-wide expression not allowed here", Default);
11504 -- Check incorrect use of dynamically tagged expressions
11506 if Is_Tagged_Type (Formal_Type) then
11507 Check_Dynamically_Tagged_Expression
11509 Typ => Formal_Type,
11510 Related_Nod => Default);
11514 -- Ada 2005 (AI-231): Static checks
11516 if Ada_Version >= Ada_2005
11517 and then Is_Access_Type (Etype (Formal))
11518 and then Can_Never_Be_Null (Etype (Formal))
11520 Null_Exclusion_Static_Checks (Param_Spec);
11523 -- The following checks are relevant only when SPARK_Mode is on as
11524 -- these are not standard Ada legality rules.
11526 if SPARK_Mode = On then
11527 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11529 -- A function cannot have a parameter of mode IN OUT or OUT
11532 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11534 ("function cannot have parameter of mode `OUT` or "
11535 & "`IN OUT`", Formal);
11538 -- A procedure cannot have an effectively volatile formal
11539 -- parameter of mode IN because it behaves as a constant
11540 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11542 elsif Ekind (Scope (Formal)) = E_Procedure
11543 and then Ekind (Formal) = E_In_Parameter
11544 and then Is_Effectively_Volatile (Formal)
11547 ("formal parameter of mode `IN` cannot be volatile", Formal);
11555 -- If this is the formal part of a function specification, analyze the
11556 -- subtype mark in the context where the formals are visible but not
11557 -- yet usable, and may hide outer homographs.
11559 if Nkind (Related_Nod) = N_Function_Specification then
11560 Analyze_Return_Type (Related_Nod);
11563 -- Now set the kind (mode) of each formal
11565 Param_Spec := First (T);
11566 while Present (Param_Spec) loop
11567 Formal := Defining_Identifier (Param_Spec);
11568 Set_Formal_Mode (Formal);
11570 if Ekind (Formal) = E_In_Parameter then
11571 Set_Default_Value (Formal, Expression (Param_Spec));
11573 if Present (Expression (Param_Spec)) then
11574 Default := Expression (Param_Spec);
11576 if Is_Scalar_Type (Etype (Default)) then
11577 if Nkind (Parameter_Type (Param_Spec)) /=
11578 N_Access_Definition
11580 Formal_Type := Entity (Parameter_Type (Param_Spec));
11584 (Related_Nod, Parameter_Type (Param_Spec));
11587 Apply_Scalar_Range_Check (Default, Formal_Type);
11591 elsif Ekind (Formal) = E_Out_Parameter then
11592 Num_Out_Params := Num_Out_Params + 1;
11594 if Num_Out_Params = 1 then
11595 First_Out_Param := Formal;
11598 elsif Ekind (Formal) = E_In_Out_Parameter then
11599 Num_Out_Params := Num_Out_Params + 1;
11602 -- Skip remaining processing if formal type was in error
11604 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11605 goto Next_Parameter;
11608 -- Force call by reference if aliased
11611 Conv : constant Convention_Id := Convention (Etype (Formal));
11613 if Is_Aliased (Formal) then
11614 Set_Mechanism (Formal, By_Reference);
11616 -- Warn if user asked this to be passed by copy
11618 if Conv = Convention_Ada_Pass_By_Copy then
11620 ("cannot pass aliased parameter & by copy??", Formal);
11623 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11625 elsif Conv = Convention_Ada_Pass_By_Copy then
11626 Set_Mechanism (Formal, By_Copy);
11628 elsif Conv = Convention_Ada_Pass_By_Reference then
11629 Set_Mechanism (Formal, By_Reference);
11637 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11638 Set_Is_Only_Out_Parameter (First_Out_Param);
11640 end Process_Formals;
11642 ----------------------------
11643 -- Reference_Body_Formals --
11644 ----------------------------
11646 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11651 if Error_Posted (Spec) then
11655 -- Iterate over both lists. They may be of different lengths if the two
11656 -- specs are not conformant.
11658 Fs := First_Formal (Spec);
11659 Fb := First_Formal (Bod);
11660 while Present (Fs) and then Present (Fb) loop
11661 Generate_Reference (Fs, Fb, 'b');
11663 if Style_Check then
11664 Style.Check_Identifier (Fb, Fs);
11667 Set_Spec_Entity (Fb, Fs);
11668 Set_Referenced (Fs, False);
11672 end Reference_Body_Formals;
11674 -------------------------
11675 -- Set_Actual_Subtypes --
11676 -------------------------
11678 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11680 Formal : Entity_Id;
11682 First_Stmt : Node_Id := Empty;
11683 AS_Needed : Boolean;
11686 -- If this is an empty initialization procedure, no need to create
11687 -- actual subtypes (small optimization).
11689 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11692 -- Within a predicate function we do not want to generate local
11693 -- subtypes that may generate nested predicate functions.
11695 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11699 -- The subtype declarations may freeze the formals. The body generated
11700 -- for an expression function is not a freeze point, so do not emit
11701 -- these declarations (small loss of efficiency in rare cases).
11703 if Nkind (N) = N_Subprogram_Body
11704 and then Was_Expression_Function (N)
11709 Formal := First_Formal (Subp);
11710 while Present (Formal) loop
11711 T := Etype (Formal);
11713 -- We never need an actual subtype for a constrained formal
11715 if Is_Constrained (T) then
11716 AS_Needed := False;
11718 -- If we have unknown discriminants, then we do not need an actual
11719 -- subtype, or more accurately we cannot figure it out. Note that
11720 -- all class-wide types have unknown discriminants.
11722 elsif Has_Unknown_Discriminants (T) then
11723 AS_Needed := False;
11725 -- At this stage we have an unconstrained type that may need an
11726 -- actual subtype. For sure the actual subtype is needed if we have
11727 -- an unconstrained array type. However, in an instance, the type
11728 -- may appear as a subtype of the full view, while the actual is
11729 -- in fact private (in which case no actual subtype is needed) so
11730 -- check the kind of the base type.
11732 elsif Is_Array_Type (Base_Type (T)) then
11735 -- The only other case needing an actual subtype is an unconstrained
11736 -- record type which is an IN parameter (we cannot generate actual
11737 -- subtypes for the OUT or IN OUT case, since an assignment can
11738 -- change the discriminant values. However we exclude the case of
11739 -- initialization procedures, since discriminants are handled very
11740 -- specially in this context, see the section entitled "Handling of
11741 -- Discriminants" in Einfo.
11743 -- We also exclude the case of Discrim_SO_Functions (functions used
11744 -- in front-end layout mode for size/offset values), since in such
11745 -- functions only discriminants are referenced, and not only are such
11746 -- subtypes not needed, but they cannot always be generated, because
11747 -- of order of elaboration issues.
11749 elsif Is_Record_Type (T)
11750 and then Ekind (Formal) = E_In_Parameter
11751 and then Chars (Formal) /= Name_uInit
11752 and then not Is_Unchecked_Union (T)
11753 and then not Is_Discrim_SO_Function (Subp)
11757 -- All other cases do not need an actual subtype
11760 AS_Needed := False;
11763 -- Generate actual subtypes for unconstrained arrays and
11764 -- unconstrained discriminated records.
11767 if Nkind (N) = N_Accept_Statement then
11769 -- If expansion is active, the formal is replaced by a local
11770 -- variable that renames the corresponding entry of the
11771 -- parameter block, and it is this local variable that may
11772 -- require an actual subtype.
11774 if Expander_Active then
11775 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11777 Decl := Build_Actual_Subtype (T, Formal);
11780 if Present (Handled_Statement_Sequence (N)) then
11782 First (Statements (Handled_Statement_Sequence (N)));
11783 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11784 Mark_Rewrite_Insertion (Decl);
11786 -- If the accept statement has no body, there will be no
11787 -- reference to the actuals, so no need to compute actual
11794 Decl := Build_Actual_Subtype (T, Formal);
11795 Prepend (Decl, Declarations (N));
11796 Mark_Rewrite_Insertion (Decl);
11799 -- The declaration uses the bounds of an existing object, and
11800 -- therefore needs no constraint checks.
11802 Analyze (Decl, Suppress => All_Checks);
11803 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11805 -- We need to freeze manually the generated type when it is
11806 -- inserted anywhere else than in a declarative part.
11808 if Present (First_Stmt) then
11809 Insert_List_Before_And_Analyze (First_Stmt,
11810 Freeze_Entity (Defining_Identifier (Decl), N));
11812 -- Ditto if the type has a dynamic predicate, because the
11813 -- generated function will mention the actual subtype. The
11814 -- predicate may come from an explicit aspect of be inherited.
11816 elsif Has_Predicates (T) then
11817 Insert_List_Before_And_Analyze (Decl,
11818 Freeze_Entity (Defining_Identifier (Decl), N));
11821 if Nkind (N) = N_Accept_Statement
11822 and then Expander_Active
11824 Set_Actual_Subtype (Renamed_Object (Formal),
11825 Defining_Identifier (Decl));
11827 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11831 Next_Formal (Formal);
11833 end Set_Actual_Subtypes;
11835 ---------------------
11836 -- Set_Formal_Mode --
11837 ---------------------
11839 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11840 Spec : constant Node_Id := Parent (Formal_Id);
11841 Id : constant Entity_Id := Scope (Formal_Id);
11844 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11845 -- since we ensure that corresponding actuals are always valid at the
11846 -- point of the call.
11848 if Out_Present (Spec) then
11849 if Ekind_In (Id, E_Entry, E_Entry_Family)
11850 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11852 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11855 if Ekind_In (Id, E_Function, E_Generic_Function) then
11857 -- [IN] OUT parameters allowed for functions in Ada 2012
11859 if Ada_Version >= Ada_2012 then
11861 -- Even in Ada 2012 operators can only have IN parameters
11863 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11864 Error_Msg_N ("operators can only have IN parameters", Spec);
11867 if In_Present (Spec) then
11868 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11870 Set_Ekind (Formal_Id, E_Out_Parameter);
11873 -- But not in earlier versions of Ada
11876 Error_Msg_N ("functions can only have IN parameters", Spec);
11877 Set_Ekind (Formal_Id, E_In_Parameter);
11880 elsif In_Present (Spec) then
11881 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11884 Set_Ekind (Formal_Id, E_Out_Parameter);
11885 Set_Never_Set_In_Source (Formal_Id, True);
11886 Set_Is_True_Constant (Formal_Id, False);
11887 Set_Current_Value (Formal_Id, Empty);
11891 Set_Ekind (Formal_Id, E_In_Parameter);
11894 -- Set Is_Known_Non_Null for access parameters since the language
11895 -- guarantees that access parameters are always non-null. We also set
11896 -- Can_Never_Be_Null, since there is no way to change the value.
11898 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11900 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11901 -- null; In Ada 2005, only if then null_exclusion is explicit.
11903 if Ada_Version < Ada_2005
11904 or else Can_Never_Be_Null (Etype (Formal_Id))
11906 Set_Is_Known_Non_Null (Formal_Id);
11907 Set_Can_Never_Be_Null (Formal_Id);
11910 -- Ada 2005 (AI-231): Null-exclusion access subtype
11912 elsif Is_Access_Type (Etype (Formal_Id))
11913 and then Can_Never_Be_Null (Etype (Formal_Id))
11915 Set_Is_Known_Non_Null (Formal_Id);
11917 -- We can also set Can_Never_Be_Null (thus preventing some junk
11918 -- access checks) for the case of an IN parameter, which cannot
11919 -- be changed, or for an IN OUT parameter, which can be changed but
11920 -- not to a null value. But for an OUT parameter, the initial value
11921 -- passed in can be null, so we can't set this flag in that case.
11923 if Ekind (Formal_Id) /= E_Out_Parameter then
11924 Set_Can_Never_Be_Null (Formal_Id);
11928 Set_Mechanism (Formal_Id, Default_Mechanism);
11929 Set_Formal_Validity (Formal_Id);
11930 end Set_Formal_Mode;
11932 -------------------------
11933 -- Set_Formal_Validity --
11934 -------------------------
11936 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11938 -- If no validity checking, then we cannot assume anything about the
11939 -- validity of parameters, since we do not know there is any checking
11940 -- of the validity on the call side.
11942 if not Validity_Checks_On then
11945 -- If validity checking for parameters is enabled, this means we are
11946 -- not supposed to make any assumptions about argument values.
11948 elsif Validity_Check_Parameters then
11951 -- If we are checking in parameters, we will assume that the caller is
11952 -- also checking parameters, so we can assume the parameter is valid.
11954 elsif Ekind (Formal_Id) = E_In_Parameter
11955 and then Validity_Check_In_Params
11957 Set_Is_Known_Valid (Formal_Id, True);
11959 -- Similar treatment for IN OUT parameters
11961 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11962 and then Validity_Check_In_Out_Params
11964 Set_Is_Known_Valid (Formal_Id, True);
11966 end Set_Formal_Validity;
11968 ------------------------
11969 -- Subtype_Conformant --
11970 ------------------------
11972 function Subtype_Conformant
11973 (New_Id : Entity_Id;
11974 Old_Id : Entity_Id;
11975 Skip_Controlling_Formals : Boolean := False) return Boolean
11979 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
11980 Skip_Controlling_Formals => Skip_Controlling_Formals);
11982 end Subtype_Conformant;
11984 ---------------------
11985 -- Type_Conformant --
11986 ---------------------
11988 function Type_Conformant
11989 (New_Id : Entity_Id;
11990 Old_Id : Entity_Id;
11991 Skip_Controlling_Formals : Boolean := False) return Boolean
11995 May_Hide_Profile := False;
11997 (New_Id, Old_Id, Type_Conformant, False, Result,
11998 Skip_Controlling_Formals => Skip_Controlling_Formals);
12000 end Type_Conformant;
12002 -------------------------------
12003 -- Valid_Operator_Definition --
12004 -------------------------------
12006 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12009 Id : constant Name_Id := Chars (Designator);
12013 F := First_Formal (Designator);
12014 while Present (F) loop
12017 if Present (Default_Value (F)) then
12019 ("default values not allowed for operator parameters",
12022 -- For function instantiations that are operators, we must check
12023 -- separately that the corresponding generic only has in-parameters.
12024 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12025 -- an error could not arise in earlier versions of the language.
12027 elsif Ekind (F) /= E_In_Parameter then
12028 Error_Msg_N ("operators can only have IN parameters", F);
12034 -- Verify that user-defined operators have proper number of arguments
12035 -- First case of operators which can only be unary
12037 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12040 -- Case of operators which can be unary or binary
12042 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12043 N_OK := (N in 1 .. 2);
12045 -- All other operators can only be binary
12053 ("incorrect number of arguments for operator", Designator);
12057 and then Base_Type (Etype (Designator)) = Standard_Boolean
12058 and then not Is_Intrinsic_Subprogram (Designator)
12061 ("explicit definition of inequality not allowed", Designator);
12063 end Valid_Operator_Definition;