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 the SPARK mode from the current context (may be overwritten later
230 -- with explicit pragma).
232 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
233 Set_SPARK_Pragma_Inherited (Subp_Id);
235 -- Preserve relevant elaboration-related attributes of the context which
236 -- are no longer available or very expensive to recompute once analysis,
237 -- resolution, and expansion are over.
239 Mark_Elaboration_Attributes
243 Set_Is_Abstract_Subprogram (Subp_Id);
244 New_Overloaded_Entity (Subp_Id);
245 Check_Delayed_Subprogram (Subp_Id);
247 Set_Categorization_From_Scope (Subp_Id, Scop);
249 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
250 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
252 -- Issue a warning if the abstract subprogram is neither a dispatching
253 -- operation nor an operation that overrides an inherited subprogram or
254 -- predefined operator, since this most likely indicates a mistake.
256 elsif Warn_On_Redundant_Constructs
257 and then not Is_Dispatching_Operation (Subp_Id)
258 and then not Present (Overridden_Operation (Subp_Id))
259 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
260 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
263 ("abstract subprogram is not dispatching or overriding?r?", N);
266 Generate_Reference_To_Formals (Subp_Id);
267 Check_Eliminated (Subp_Id);
269 if Has_Aspects (N) then
270 Analyze_Aspect_Specifications (N, Subp_Id);
272 end Analyze_Abstract_Subprogram_Declaration;
274 ---------------------------------
275 -- Analyze_Expression_Function --
276 ---------------------------------
278 procedure Analyze_Expression_Function (N : Node_Id) is
279 Expr : constant Node_Id := Expression (N);
280 Loc : constant Source_Ptr := Sloc (N);
281 LocX : constant Source_Ptr := Sloc (Expr);
282 Spec : constant Node_Id := Specification (N);
284 procedure Freeze_Expr_Types (Def_Id : Entity_Id);
285 -- N is an expression function that is a completion and Def_Id its
286 -- defining entity. Freeze before N all the types referenced by the
287 -- expression of the function.
289 -----------------------
290 -- Freeze_Expr_Types --
291 -----------------------
293 procedure Freeze_Expr_Types (Def_Id : Entity_Id) is
294 function Cloned_Expression return Node_Id;
295 -- Build a duplicate of the expression of the return statement that
296 -- has no defining entities shared with the original expression.
298 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result;
299 -- Freeze all types referenced in the subtree rooted at Node
301 -----------------------
302 -- Cloned_Expression --
303 -----------------------
305 function Cloned_Expression return Node_Id is
306 function Clone_Id (Node : Node_Id) return Traverse_Result;
307 -- Tree traversal routine that clones the defining identifier of
308 -- iterator and loop parameter specification nodes.
314 function Clone_Id (Node : Node_Id) return Traverse_Result is
316 if Nkind_In (Node, N_Iterator_Specification,
317 N_Loop_Parameter_Specification)
319 Set_Defining_Identifier (Node,
320 New_Copy (Defining_Identifier (Node)));
326 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id);
330 Dup_Expr : constant Node_Id := New_Copy_Tree (Expr);
332 -- Start of processing for Cloned_Expression
335 -- We must duplicate the expression with semantic information to
336 -- inherit the decoration of global entities in generic instances.
337 -- Set the parent of the new node to be the parent of the original
338 -- to get the proper context, which is needed for complete error
339 -- reporting and for semantic analysis.
341 Set_Parent (Dup_Expr, Parent (Expr));
343 -- Replace the defining identifier of iterators and loop param
344 -- specifications by a clone to ensure that the cloned expression
345 -- and the original expression don't have shared identifiers;
346 -- otherwise, as part of the preanalysis of the expression, these
347 -- shared identifiers may be left decorated with itypes which
348 -- will not be available in the tree passed to the backend.
350 Clone_Def_Ids (Dup_Expr);
353 end Cloned_Expression;
355 ----------------------
356 -- Freeze_Type_Refs --
357 ----------------------
359 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is
360 procedure Check_And_Freeze_Type (Typ : Entity_Id);
361 -- Check that Typ is fully declared and freeze it if so
363 ---------------------------
364 -- Check_And_Freeze_Type --
365 ---------------------------
367 procedure Check_And_Freeze_Type (Typ : Entity_Id) is
369 -- Skip Itypes created by the preanalysis
372 and then Scope_Within_Or_Same (Scope (Typ), Def_Id)
377 -- This provides a better error message than generating
378 -- primitives whose compilation fails much later. Refine
379 -- the error message if possible.
381 Check_Fully_Declared (Typ, Node);
383 if Error_Posted (Node) then
384 if Has_Private_Component (Typ)
385 and then not Is_Private_Type (Typ)
387 Error_Msg_NE ("\type& has private component", Node, Typ);
391 Freeze_Before (N, Typ);
393 end Check_And_Freeze_Type;
395 -- Start of processing for Freeze_Type_Refs
398 -- Check that a type referenced by an entity can be frozen
400 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
401 Check_And_Freeze_Type (Etype (Entity (Node)));
403 -- Check that the enclosing record type can be frozen
405 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
406 Check_And_Freeze_Type (Scope (Entity (Node)));
409 -- Freezing an access type does not freeze the designated type,
410 -- but freezing conversions between access to interfaces requires
411 -- that the interface types themselves be frozen, so that dispatch
412 -- table entities are properly created.
414 -- Unclear whether a more general rule is needed ???
416 elsif Nkind (Node) = N_Type_Conversion
417 and then Is_Access_Type (Etype (Node))
418 and then Is_Interface (Designated_Type (Etype (Node)))
420 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
423 -- No point in posting several errors on the same expression
425 if Serious_Errors_Detected > 0 then
430 end Freeze_Type_Refs;
432 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs);
436 Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id);
437 Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id);
438 Dup_Expr : constant Node_Id := Cloned_Expression;
440 -- Start of processing for Freeze_Expr_Types
443 -- Preanalyze a duplicate of the expression to have available the
444 -- minimum decoration needed to locate referenced unfrozen types
445 -- without adding any decoration to the function expression.
448 Install_Formals (Def_Id);
450 Preanalyze_Spec_Expression (Dup_Expr, Etype (Def_Id));
453 -- Restore certain attributes of Def_Id since the preanalysis may
454 -- have introduced itypes to this scope, thus modifying attributes
455 -- First_Entity and Last_Entity.
457 Set_First_Entity (Def_Id, Saved_First_Entity);
458 Set_Last_Entity (Def_Id, Saved_Last_Entity);
460 if Present (Last_Entity (Def_Id)) then
461 Set_Next_Entity (Last_Entity (Def_Id), Empty);
464 -- Freeze all types referenced in the expression
466 Freeze_References (Dup_Expr);
467 end Freeze_Expr_Types;
477 Def_Id : Entity_Id := Empty;
479 -- If the expression is a completion, Prev is the entity whose
480 -- declaration is completed. Def_Id is needed to analyze the spec.
482 -- Start of processing for Analyze_Expression_Function
485 -- This is one of the occasions on which we transform the tree during
486 -- semantic analysis. If this is a completion, transform the expression
487 -- function into an equivalent subprogram body, and analyze it.
489 -- Expression functions are inlined unconditionally. The back-end will
490 -- determine whether this is possible.
492 Inline_Processing_Required := True;
494 -- Create a specification for the generated body. This must be done
495 -- prior to the analysis of the initial declaration.
497 New_Spec := Copy_Subprogram_Spec (Spec);
498 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
500 -- If there are previous overloadable entities with the same name,
501 -- check whether any of them is completed by the expression function.
502 -- In a generic context a formal subprogram has no completion.
505 and then Is_Overloadable (Prev)
506 and then not Is_Formal_Subprogram (Prev)
508 Def_Id := Analyze_Subprogram_Specification (Spec);
509 Prev := Find_Corresponding_Spec (N);
511 -- The previous entity may be an expression function as well, in
512 -- which case the redeclaration is illegal.
515 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
516 N_Expression_Function
518 Error_Msg_Sloc := Sloc (Prev);
519 Error_Msg_N ("& conflicts with declaration#", Def_Id);
524 Ret := Make_Simple_Return_Statement (LocX, Expr);
527 Make_Subprogram_Body (Loc,
528 Specification => New_Spec,
529 Declarations => Empty_List,
530 Handled_Statement_Sequence =>
531 Make_Handled_Sequence_Of_Statements (LocX,
532 Statements => New_List (Ret)));
533 Set_Was_Expression_Function (New_Body);
535 -- If the expression completes a generic subprogram, we must create a
536 -- separate node for the body, because at instantiation the original
537 -- node of the generic copy must be a generic subprogram body, and
538 -- cannot be a expression function. Otherwise we just rewrite the
539 -- expression with the non-generic body.
541 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
542 Insert_After (N, New_Body);
544 -- Propagate any aspects or pragmas that apply to the expression
545 -- function to the proper body when the expression function acts
548 if Has_Aspects (N) then
549 Move_Aspects (N, To => New_Body);
552 Relocate_Pragmas_To_Body (New_Body);
554 Rewrite (N, Make_Null_Statement (Loc));
555 Set_Has_Completion (Prev, False);
558 Set_Is_Inlined (Prev);
560 -- If the expression function is a completion, the previous declaration
561 -- must come from source. We know already that it appears in the current
562 -- scope. The entity itself may be internally created if within a body
566 and then Is_Overloadable (Prev)
567 and then not Is_Formal_Subprogram (Prev)
568 and then Comes_From_Source (Parent (Prev))
570 Set_Has_Completion (Prev, False);
571 Set_Is_Inlined (Prev);
573 -- AI12-0103: Expression functions that are a completion freeze their
574 -- expression but don't freeze anything else (unlike regular bodies).
576 -- Note that we cannot defer this freezing to the analysis of the
577 -- expression itself, because a freeze node might appear in a nested
578 -- scope, leading to an elaboration order issue in gigi.
579 -- As elsewhere, we do not emit freeze nodes within a generic unit.
581 if not Inside_A_Generic then
582 Freeze_Expr_Types (Def_Id);
585 -- For navigation purposes, indicate that the function is a body
587 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
588 Rewrite (N, New_Body);
590 -- Remove any existing aspects from the original node because the act
591 -- of rewriting causes the list to be shared between the two nodes.
593 Orig_N := Original_Node (N);
594 Remove_Aspects (Orig_N);
596 -- Propagate any pragmas that apply to expression function to the
597 -- proper body when the expression function acts as a completion.
598 -- Aspects are automatically transfered because of node rewriting.
600 Relocate_Pragmas_To_Body (N);
603 -- Once the aspects of the generated body have been analyzed, create
604 -- a copy for ASIS purposes and associate it with the original node.
606 if Has_Aspects (N) then
607 Set_Aspect_Specifications (Orig_N,
608 New_Copy_List_Tree (Aspect_Specifications (N)));
611 -- Prev is the previous entity with the same name, but it is can
612 -- be an unrelated spec that is not completed by the expression
613 -- function. In that case the relevant entity is the one in the body.
614 -- Not clear that the backend can inline it in this case ???
616 if Has_Completion (Prev) then
618 -- The formals of the expression function are body formals,
619 -- and do not appear in the ali file, which will only contain
620 -- references to the formals of the original subprogram spec.
627 F1 := First_Formal (Def_Id);
628 F2 := First_Formal (Prev);
630 while Present (F1) loop
631 Set_Spec_Entity (F1, F2);
638 Set_Is_Inlined (Defining_Entity (New_Body));
641 -- If this is not a completion, create both a declaration and a body, so
642 -- that the expression can be inlined whenever possible.
645 -- An expression function that is not a completion is not a
646 -- subprogram declaration, and thus cannot appear in a protected
649 if Nkind (Parent (N)) = N_Protected_Definition then
651 ("an expression function is not a legal protected operation", N);
654 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
656 -- Remove any existing aspects from the original node because the act
657 -- of rewriting causes the list to be shared between the two nodes.
659 Orig_N := Original_Node (N);
660 Remove_Aspects (Orig_N);
664 -- Once the aspects of the generated spec have been analyzed, create
665 -- a copy for ASIS purposes and associate it with the original node.
667 if Has_Aspects (N) then
668 Set_Aspect_Specifications (Orig_N,
669 New_Copy_List_Tree (Aspect_Specifications (N)));
672 -- If aspect SPARK_Mode was specified on the body, it needs to be
673 -- repeated both on the generated spec and the body.
675 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
677 if Present (Asp) then
678 Asp := New_Copy_Tree (Asp);
679 Set_Analyzed (Asp, False);
680 Set_Aspect_Specifications (New_Body, New_List (Asp));
683 Def_Id := Defining_Entity (N);
684 Set_Is_Inlined (Def_Id);
686 -- Establish the linkages between the spec and the body. These are
687 -- used when the expression function acts as the prefix of attribute
688 -- 'Access in order to freeze the original expression which has been
689 -- moved to the generated body.
691 Set_Corresponding_Body (N, Defining_Entity (New_Body));
692 Set_Corresponding_Spec (New_Body, Def_Id);
694 -- Within a generic pre-analyze the original expression for name
695 -- capture. The body is also generated but plays no role in
696 -- this because it is not part of the original source.
698 if Inside_A_Generic then
699 Set_Has_Completion (Def_Id);
701 Install_Formals (Def_Id);
702 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
706 -- To prevent premature freeze action, insert the new body at the end
707 -- of the current declarations, or at the end of the package spec.
708 -- However, resolve usage names now, to prevent spurious visibility
709 -- on later entities. Note that the function can now be called in
710 -- the current declarative part, which will appear to be prior to
711 -- the presence of the body in the code. There are nevertheless no
712 -- order of elaboration issues because all name resolution has taken
713 -- place at the point of declaration.
716 Decls : List_Id := List_Containing (N);
717 Expr : constant Node_Id := Expression (Ret);
718 Par : constant Node_Id := Parent (Decls);
719 Typ : constant Entity_Id := Etype (Def_Id);
722 -- If this is a wrapper created for in an instance for a formal
723 -- subprogram, insert body after declaration, to be analyzed when
724 -- the enclosing instance is analyzed.
727 and then Is_Generic_Actual_Subprogram (Def_Id)
729 Insert_After (N, New_Body);
732 if Nkind (Par) = N_Package_Specification
733 and then Decls = Visible_Declarations (Par)
734 and then Present (Private_Declarations (Par))
735 and then not Is_Empty_List (Private_Declarations (Par))
737 Decls := Private_Declarations (Par);
740 Insert_After (Last (Decls), New_Body);
742 -- Preanalyze the expression if not already done above
744 if not Inside_A_Generic then
746 Install_Formals (Def_Id);
747 Preanalyze_Spec_Expression (Expr, Typ);
748 Check_Limited_Return (Original_Node (N), Expr, Typ);
755 -- Check incorrect use of dynamically tagged expression. This doesn't
756 -- fall out automatically when analyzing the generated function body,
757 -- because Check_Dynamically_Tagged_Expression deliberately ignores
758 -- nodes that don't come from source.
761 and then Nkind (Def_Id) in N_Has_Etype
762 and then Is_Tagged_Type (Etype (Def_Id))
764 Check_Dynamically_Tagged_Expression
766 Typ => Etype (Def_Id),
767 Related_Nod => Original_Node (N));
770 -- If the return expression is a static constant, we suppress warning
771 -- messages on unused formals, which in most cases will be noise.
773 Set_Is_Trivial_Subprogram
774 (Defining_Entity (New_Body), Is_OK_Static_Expression (Expr));
775 end Analyze_Expression_Function;
777 ----------------------------------------
778 -- Analyze_Extended_Return_Statement --
779 ----------------------------------------
781 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
783 Check_Compiler_Unit ("extended return statement", N);
784 Analyze_Return_Statement (N);
785 end Analyze_Extended_Return_Statement;
787 ----------------------------
788 -- Analyze_Function_Call --
789 ----------------------------
791 procedure Analyze_Function_Call (N : Node_Id) is
792 Actuals : constant List_Id := Parameter_Associations (N);
793 Func_Nam : constant Node_Id := Name (N);
799 -- A call of the form A.B (X) may be an Ada 2005 call, which is
800 -- rewritten as B (A, X). If the rewriting is successful, the call
801 -- has been analyzed and we just return.
803 if Nkind (Func_Nam) = N_Selected_Component
804 and then Name (N) /= Func_Nam
805 and then Is_Rewrite_Substitution (N)
806 and then Present (Etype (N))
811 -- If error analyzing name, then set Any_Type as result type and return
813 if Etype (Func_Nam) = Any_Type then
814 Set_Etype (N, Any_Type);
818 -- Otherwise analyze the parameters
820 if Present (Actuals) then
821 Actual := First (Actuals);
822 while Present (Actual) loop
824 Check_Parameterless_Call (Actual);
830 end Analyze_Function_Call;
832 -----------------------------
833 -- Analyze_Function_Return --
834 -----------------------------
836 procedure Analyze_Function_Return (N : Node_Id) is
837 Loc : constant Source_Ptr := Sloc (N);
838 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
839 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
841 R_Type : constant Entity_Id := Etype (Scope_Id);
842 -- Function result subtype
844 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
845 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
846 -- aggregate in a return statement.
848 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
849 -- Check that the return_subtype_indication properly matches the result
850 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
852 -----------------------------------
853 -- Check_Aggregate_Accessibility --
854 -----------------------------------
856 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
857 Typ : constant Entity_Id := Etype (Aggr);
864 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
865 Discr := First_Discriminant (Typ);
866 Assoc := First (Component_Associations (Aggr));
867 while Present (Discr) loop
868 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
869 Expr := Expression (Assoc);
871 if Nkind (Expr) = N_Attribute_Reference
872 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
874 Obj := Prefix (Expr);
875 while Nkind_In (Obj, N_Indexed_Component,
876 N_Selected_Component)
881 -- Do not check aliased formals or function calls. A
882 -- run-time check may still be needed ???
884 if Is_Entity_Name (Obj)
885 and then Comes_From_Source (Obj)
887 if Is_Formal (Entity (Obj))
888 and then Is_Aliased (Entity (Obj))
892 elsif Object_Access_Level (Obj) >
893 Scope_Depth (Scope (Scope_Id))
896 ("access discriminant in return aggregate would "
897 & "be a dangling reference", Obj);
903 Next_Discriminant (Discr);
906 end Check_Aggregate_Accessibility;
908 -------------------------------------
909 -- Check_Return_Subtype_Indication --
910 -------------------------------------
912 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
913 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
915 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
916 -- Subtype given in the extended return statement (must match R_Type)
918 Subtype_Ind : constant Node_Id :=
919 Object_Definition (Original_Node (Obj_Decl));
921 procedure Error_No_Match (N : Node_Id);
922 -- Output error messages for case where types do not statically
923 -- match. N is the location for the messages.
929 procedure Error_No_Match (N : Node_Id) is
932 ("subtype must statically match function result subtype", N);
934 if not Predicates_Match (R_Stm_Type, R_Type) then
935 Error_Msg_Node_2 := R_Type;
937 ("\predicate of& does not match predicate of&",
942 -- Start of processing for Check_Return_Subtype_Indication
945 -- First, avoid cascaded errors
947 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
951 -- "return access T" case; check that the return statement also has
952 -- "access T", and that the subtypes statically match:
953 -- if this is an access to subprogram the signatures must match.
955 if Is_Anonymous_Access_Type (R_Type) then
956 if Is_Anonymous_Access_Type (R_Stm_Type) then
957 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
959 if Base_Type (Designated_Type (R_Stm_Type)) /=
960 Base_Type (Designated_Type (R_Type))
961 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
963 Error_No_Match (Subtype_Mark (Subtype_Ind));
967 -- For two anonymous access to subprogram types, the types
968 -- themselves must be type conformant.
970 if not Conforming_Types
971 (R_Stm_Type, R_Type, Fully_Conformant)
973 Error_No_Match (Subtype_Ind);
978 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
981 -- If the return object is of an anonymous access type, then report
982 -- an error if the function's result type is not also anonymous.
984 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
985 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
987 ("anonymous access not allowed for function with named access "
988 & "result", Subtype_Ind);
990 -- Subtype indication case: check that the return object's type is
991 -- covered by the result type, and that the subtypes statically match
992 -- when the result subtype is constrained. Also handle record types
993 -- with unknown discriminants for which we have built the underlying
994 -- record view. Coverage is needed to allow specific-type return
995 -- objects when the result type is class-wide (see AI05-32).
997 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
998 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1001 (Base_Type (R_Type),
1002 Underlying_Record_View (Base_Type (R_Stm_Type))))
1004 -- A null exclusion may be present on the return type, on the
1005 -- function specification, on the object declaration or on the
1008 if Is_Access_Type (R_Type)
1010 (Can_Never_Be_Null (R_Type)
1011 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1012 Can_Never_Be_Null (R_Stm_Type)
1014 Error_No_Match (Subtype_Ind);
1017 -- AI05-103: for elementary types, subtypes must statically match
1019 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1020 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1021 Error_No_Match (Subtype_Ind);
1025 -- All remaining cases are illegal
1027 -- Note: previous versions of this subprogram allowed the return
1028 -- value to be the ancestor of the return type if the return type
1029 -- was a null extension. This was plainly incorrect.
1033 ("wrong type for return_subtype_indication", Subtype_Ind);
1035 end Check_Return_Subtype_Indication;
1037 ---------------------
1038 -- Local Variables --
1039 ---------------------
1044 -- Start of processing for Analyze_Function_Return
1047 Set_Return_Present (Scope_Id);
1049 if Nkind (N) = N_Simple_Return_Statement then
1050 Expr := Expression (N);
1052 -- Guard against a malformed expression. The parser may have tried to
1053 -- recover but the node is not analyzable.
1055 if Nkind (Expr) = N_Error then
1056 Set_Etype (Expr, Any_Type);
1057 Expander_Mode_Save_And_Set (False);
1061 -- The resolution of a controlled [extension] aggregate associated
1062 -- with a return statement creates a temporary which needs to be
1063 -- finalized on function exit. Wrap the return statement inside a
1064 -- block so that the finalization machinery can detect this case.
1065 -- This early expansion is done only when the return statement is
1066 -- not part of a handled sequence of statements.
1068 if Nkind_In (Expr, N_Aggregate,
1069 N_Extension_Aggregate)
1070 and then Needs_Finalization (R_Type)
1071 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1074 Make_Block_Statement (Loc,
1075 Handled_Statement_Sequence =>
1076 Make_Handled_Sequence_Of_Statements (Loc,
1077 Statements => New_List (Relocate_Node (N)))));
1085 -- Ada 2005 (AI-251): If the type of the returned object is
1086 -- an access to an interface type then we add an implicit type
1087 -- conversion to force the displacement of the "this" pointer to
1088 -- reference the secondary dispatch table. We cannot delay the
1089 -- generation of this implicit conversion until the expansion
1090 -- because in this case the type resolution changes the decoration
1091 -- of the expression node to match R_Type; by contrast, if the
1092 -- returned object is a class-wide interface type then it is too
1093 -- early to generate here the implicit conversion since the return
1094 -- statement may be rewritten by the expander into an extended
1095 -- return statement whose expansion takes care of adding the
1096 -- implicit type conversion to displace the pointer to the object.
1099 and then Serious_Errors_Detected = 0
1100 and then Is_Access_Type (R_Type)
1101 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1102 and then Is_Interface (Designated_Type (R_Type))
1103 and then Is_Progenitor (Designated_Type (R_Type),
1104 Designated_Type (Etype (Expr)))
1106 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1110 Resolve (Expr, R_Type);
1111 Check_Limited_Return (N, Expr, R_Type);
1113 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
1114 Check_Aggregate_Accessibility (Expr);
1118 -- RETURN only allowed in SPARK as the last statement in function
1120 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1122 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1123 or else Present (Next (N)))
1125 Check_SPARK_05_Restriction
1126 ("RETURN should be the last statement in function", N);
1130 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1131 Obj_Decl := Last (Return_Object_Declarations (N));
1133 -- Analyze parts specific to extended_return_statement:
1136 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1137 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1140 Expr := Expression (Obj_Decl);
1142 -- Note: The check for OK_For_Limited_Init will happen in
1143 -- Analyze_Object_Declaration; we treat it as a normal
1144 -- object declaration.
1146 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1149 Check_Return_Subtype_Indication (Obj_Decl);
1151 if Present (HSS) then
1154 if Present (Exception_Handlers (HSS)) then
1156 -- ???Has_Nested_Block_With_Handler needs to be set.
1157 -- Probably by creating an actual N_Block_Statement.
1158 -- Probably in Expand.
1164 -- Mark the return object as referenced, since the return is an
1165 -- implicit reference of the object.
1167 Set_Referenced (Defining_Identifier (Obj_Decl));
1169 Check_References (Stm_Entity);
1171 -- Check RM 6.5 (5.9/3)
1174 if Ada_Version < Ada_2012 then
1176 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1177 -- Can it really happen (extended return???)
1180 ("aliased only allowed for limited return objects "
1181 & "in Ada 2012??", N);
1183 elsif not Is_Limited_View (R_Type) then
1185 ("aliased only allowed for limited return objects", N);
1191 -- Case of Expr present
1195 -- Defend against previous errors
1197 and then Nkind (Expr) /= N_Empty
1198 and then Present (Etype (Expr))
1200 -- Apply constraint check. Note that this is done before the implicit
1201 -- conversion of the expression done for anonymous access types to
1202 -- ensure correct generation of the null-excluding check associated
1203 -- with null-excluding expressions found in return statements.
1205 Apply_Constraint_Check (Expr, R_Type);
1207 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1208 -- type, apply an implicit conversion of the expression to that type
1209 -- to force appropriate static and run-time accessibility checks.
1211 if Ada_Version >= Ada_2005
1212 and then Ekind (R_Type) = E_Anonymous_Access_Type
1214 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1215 Analyze_And_Resolve (Expr, R_Type);
1217 -- If this is a local anonymous access to subprogram, the
1218 -- accessibility check can be applied statically. The return is
1219 -- illegal if the access type of the return expression is declared
1220 -- inside of the subprogram (except if it is the subtype indication
1221 -- of an extended return statement).
1223 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1224 if not Comes_From_Source (Current_Scope)
1225 or else Ekind (Current_Scope) = E_Return_Statement
1230 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1232 Error_Msg_N ("cannot return local access to subprogram", N);
1235 -- The expression cannot be of a formal incomplete type
1237 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1238 and then Is_Generic_Type (Etype (Expr))
1241 ("cannot return expression of a formal incomplete type", N);
1244 -- If the result type is class-wide, then check that the return
1245 -- expression's type is not declared at a deeper level than the
1246 -- function (RM05-6.5(5.6/2)).
1248 if Ada_Version >= Ada_2005
1249 and then Is_Class_Wide_Type (R_Type)
1251 if Type_Access_Level (Etype (Expr)) >
1252 Subprogram_Access_Level (Scope_Id)
1255 ("level of return expression type is deeper than "
1256 & "class-wide function!", Expr);
1260 -- Check incorrect use of dynamically tagged expression
1262 if Is_Tagged_Type (R_Type) then
1263 Check_Dynamically_Tagged_Expression
1269 -- ??? A real run-time accessibility check is needed in cases
1270 -- involving dereferences of access parameters. For now we just
1271 -- check the static cases.
1273 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1274 and then Is_Limited_View (Etype (Scope_Id))
1275 and then Object_Access_Level (Expr) >
1276 Subprogram_Access_Level (Scope_Id)
1278 -- Suppress the message in a generic, where the rewriting
1281 if Inside_A_Generic then
1286 Make_Raise_Program_Error (Loc,
1287 Reason => PE_Accessibility_Check_Failed));
1290 Error_Msg_Warn := SPARK_Mode /= On;
1291 Error_Msg_N ("cannot return a local value by reference<<", N);
1292 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1296 if Known_Null (Expr)
1297 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1298 and then Null_Exclusion_Present (Parent (Scope_Id))
1300 Apply_Compile_Time_Constraint_Error
1302 Msg => "(Ada 2005) null not allowed for "
1303 & "null-excluding return??",
1304 Reason => CE_Null_Not_Allowed);
1307 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1308 -- has no initializing expression.
1310 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1311 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1312 Subprogram_Access_Level (Scope_Id)
1315 ("level of return expression type is deeper than "
1316 & "class-wide function!", Obj_Decl);
1319 end Analyze_Function_Return;
1321 -------------------------------------
1322 -- Analyze_Generic_Subprogram_Body --
1323 -------------------------------------
1325 procedure Analyze_Generic_Subprogram_Body
1329 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1330 Kind : constant Entity_Kind := Ekind (Gen_Id);
1331 Body_Id : Entity_Id;
1336 -- Copy body and disable expansion while analyzing the generic For a
1337 -- stub, do not copy the stub (which would load the proper body), this
1338 -- will be done when the proper body is analyzed.
1340 if Nkind (N) /= N_Subprogram_Body_Stub then
1341 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1344 -- Once the contents of the generic copy and the template are
1345 -- swapped, do the same for their respective aspect specifications.
1347 Exchange_Aspects (N, New_N);
1349 -- Collect all contract-related source pragmas found within the
1350 -- template and attach them to the contract of the subprogram body.
1351 -- This contract is used in the capture of global references within
1354 Create_Generic_Contract (N);
1359 Spec := Specification (N);
1361 -- Within the body of the generic, the subprogram is callable, and
1362 -- behaves like the corresponding non-generic unit.
1364 Body_Id := Defining_Entity (Spec);
1366 if Kind = E_Generic_Procedure
1367 and then Nkind (Spec) /= N_Procedure_Specification
1369 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1372 elsif Kind = E_Generic_Function
1373 and then Nkind (Spec) /= N_Function_Specification
1375 Error_Msg_N ("invalid body for generic function ", Body_Id);
1379 Set_Corresponding_Body (Gen_Decl, Body_Id);
1381 if Has_Completion (Gen_Id)
1382 and then Nkind (Parent (N)) /= N_Subunit
1384 Error_Msg_N ("duplicate generic body", N);
1387 Set_Has_Completion (Gen_Id);
1390 if Nkind (N) = N_Subprogram_Body_Stub then
1391 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1393 Set_Corresponding_Spec (N, Gen_Id);
1396 if Nkind (Parent (N)) = N_Compilation_Unit then
1397 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1400 -- Make generic parameters immediately visible in the body. They are
1401 -- needed to process the formals declarations. Then make the formals
1402 -- visible in a separate step.
1404 Push_Scope (Gen_Id);
1408 First_Ent : Entity_Id;
1411 First_Ent := First_Entity (Gen_Id);
1414 while Present (E) and then not Is_Formal (E) loop
1419 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1421 -- Now generic formals are visible, and the specification can be
1422 -- analyzed, for subsequent conformance check.
1424 Body_Id := Analyze_Subprogram_Specification (Spec);
1426 -- Make formal parameters visible
1430 -- E is the first formal parameter, we loop through the formals
1431 -- installing them so that they will be visible.
1433 Set_First_Entity (Gen_Id, E);
1434 while Present (E) loop
1440 -- Visible generic entity is callable within its own body
1442 Set_Ekind (Gen_Id, Ekind (Body_Id));
1443 Set_Ekind (Body_Id, E_Subprogram_Body);
1444 Set_Convention (Body_Id, Convention (Gen_Id));
1445 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1446 Set_Scope (Body_Id, Scope (Gen_Id));
1448 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1450 if Nkind (N) = N_Subprogram_Body_Stub then
1452 -- No body to analyze, so restore state of generic unit
1454 Set_Ekind (Gen_Id, Kind);
1455 Set_Ekind (Body_Id, Kind);
1457 if Present (First_Ent) then
1458 Set_First_Entity (Gen_Id, First_Ent);
1465 -- If this is a compilation unit, it must be made visible explicitly,
1466 -- because the compilation of the declaration, unlike other library
1467 -- unit declarations, does not. If it is not a unit, the following
1468 -- is redundant but harmless.
1470 Set_Is_Immediately_Visible (Gen_Id);
1471 Reference_Body_Formals (Gen_Id, Body_Id);
1473 if Is_Child_Unit (Gen_Id) then
1474 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1477 Set_Actual_Subtypes (N, Current_Scope);
1479 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1480 Set_SPARK_Pragma_Inherited (Body_Id);
1482 -- Analyze any aspect specifications that appear on the generic
1485 if Has_Aspects (N) then
1486 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
1489 Analyze_Declarations (Declarations (N));
1492 -- Process the contract of the subprogram body after all declarations
1493 -- have been analyzed. This ensures that any contract-related pragmas
1494 -- are available through the N_Contract node of the body.
1496 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1498 Analyze (Handled_Statement_Sequence (N));
1499 Save_Global_References (Original_Node (N));
1501 -- Prior to exiting the scope, include generic formals again (if any
1502 -- are present) in the set of local entities.
1504 if Present (First_Ent) then
1505 Set_First_Entity (Gen_Id, First_Ent);
1508 Check_References (Gen_Id);
1511 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1512 Update_Use_Clause_Chain;
1513 Validate_Categorization_Dependency (N, Gen_Id);
1515 Check_Subprogram_Order (N);
1517 -- Outside of its body, unit is generic again
1519 Set_Ekind (Gen_Id, Kind);
1520 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1523 Style.Check_Identifier (Body_Id, Gen_Id);
1527 end Analyze_Generic_Subprogram_Body;
1529 ----------------------------
1530 -- Analyze_Null_Procedure --
1531 ----------------------------
1533 procedure Analyze_Null_Procedure
1535 Is_Completion : out Boolean)
1537 Loc : constant Source_Ptr := Sloc (N);
1538 Spec : constant Node_Id := Specification (N);
1539 Designator : Entity_Id;
1541 Null_Body : Node_Id := Empty;
1542 Null_Stmt : Node_Id := Null_Statement (Spec);
1546 -- Capture the profile of the null procedure before analysis, for
1547 -- expansion at the freeze point and at each point of call. The body is
1548 -- used if the procedure has preconditions, or if it is a completion. In
1549 -- the first case the body is analyzed at the freeze point, in the other
1550 -- it replaces the null procedure declaration.
1552 -- For a null procedure that comes from source, a NULL statement is
1553 -- provided by the parser, which carries the source location of the
1554 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1555 -- from expansion, create one now.
1557 if No (Null_Stmt) then
1558 Null_Stmt := Make_Null_Statement (Loc);
1562 Make_Subprogram_Body (Loc,
1563 Specification => New_Copy_Tree (Spec),
1564 Declarations => New_List,
1565 Handled_Statement_Sequence =>
1566 Make_Handled_Sequence_Of_Statements (Loc,
1567 Statements => New_List (Null_Stmt)));
1569 -- Create new entities for body and formals
1571 Set_Defining_Unit_Name (Specification (Null_Body),
1572 Make_Defining_Identifier
1573 (Sloc (Defining_Entity (N)),
1574 Chars (Defining_Entity (N))));
1576 Form := First (Parameter_Specifications (Specification (Null_Body)));
1577 while Present (Form) loop
1578 Set_Defining_Identifier (Form,
1579 Make_Defining_Identifier
1580 (Sloc (Defining_Identifier (Form)),
1581 Chars (Defining_Identifier (Form))));
1585 -- Determine whether the null procedure may be a completion of a generic
1586 -- suprogram, in which case we use the new null body as the completion
1587 -- and set minimal semantic information on the original declaration,
1588 -- which is rewritten as a null statement.
1590 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1592 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1593 Insert_Before (N, Null_Body);
1594 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1596 Rewrite (N, Make_Null_Statement (Loc));
1597 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1598 Is_Completion := True;
1602 -- Resolve the types of the formals now, because the freeze point may
1603 -- appear in a different context, e.g. an instantiation.
1605 Form := First (Parameter_Specifications (Specification (Null_Body)));
1606 while Present (Form) loop
1607 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1608 Find_Type (Parameter_Type (Form));
1610 elsif No (Access_To_Subprogram_Definition
1611 (Parameter_Type (Form)))
1613 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1615 -- The case of a null procedure with a formal that is an
1616 -- access-to-subprogram type, and that is used as an actual
1617 -- in an instantiation is left to the enthusiastic reader.
1627 -- If there are previous overloadable entities with the same name, check
1628 -- whether any of them is completed by the null procedure.
1630 if Present (Prev) and then Is_Overloadable (Prev) then
1631 Designator := Analyze_Subprogram_Specification (Spec);
1632 Prev := Find_Corresponding_Spec (N);
1635 if No (Prev) or else not Comes_From_Source (Prev) then
1636 Designator := Analyze_Subprogram_Specification (Spec);
1637 Set_Has_Completion (Designator);
1639 -- Signal to caller that this is a procedure declaration
1641 Is_Completion := False;
1643 -- Null procedures are always inlined, but generic formal subprograms
1644 -- which appear as such in the internal instance of formal packages,
1645 -- need no completion and are not marked Inline.
1648 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1650 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1651 Set_Body_To_Inline (N, Null_Body);
1652 Set_Is_Inlined (Designator);
1656 -- The null procedure is a completion. We unconditionally rewrite
1657 -- this as a null body (even if expansion is not active), because
1658 -- there are various error checks that are applied on this body
1659 -- when it is analyzed (e.g. correct aspect placement).
1661 if Has_Completion (Prev) then
1662 Error_Msg_Sloc := Sloc (Prev);
1663 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1666 Check_Previous_Null_Procedure (N, Prev);
1668 Is_Completion := True;
1669 Rewrite (N, Null_Body);
1672 end Analyze_Null_Procedure;
1674 -----------------------------
1675 -- Analyze_Operator_Symbol --
1676 -----------------------------
1678 -- An operator symbol such as "+" or "and" may appear in context where the
1679 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1680 -- is just a string, as in (conjunction = "or"). In these cases the parser
1681 -- generates this node, and the semantics does the disambiguation. Other
1682 -- such case are actuals in an instantiation, the generic unit in an
1683 -- instantiation, and pragma arguments.
1685 procedure Analyze_Operator_Symbol (N : Node_Id) is
1686 Par : constant Node_Id := Parent (N);
1689 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1690 or else Nkind (Par) = N_Function_Instantiation
1691 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1692 or else (Nkind (Par) = N_Pragma_Argument_Association
1693 and then not Is_Pragma_String_Literal (Par))
1694 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1695 or else (Nkind (Par) = N_Attribute_Reference
1696 and then Attribute_Name (Par) /= Name_Value)
1698 Find_Direct_Name (N);
1701 Change_Operator_Symbol_To_String_Literal (N);
1704 end Analyze_Operator_Symbol;
1706 -----------------------------------
1707 -- Analyze_Parameter_Association --
1708 -----------------------------------
1710 procedure Analyze_Parameter_Association (N : Node_Id) is
1712 Analyze (Explicit_Actual_Parameter (N));
1713 end Analyze_Parameter_Association;
1715 ----------------------------
1716 -- Analyze_Procedure_Call --
1717 ----------------------------
1719 -- WARNING: This routine manages Ghost regions. Return statements must be
1720 -- replaced by gotos which jump to the end of the routine and restore the
1723 procedure Analyze_Procedure_Call (N : Node_Id) is
1724 procedure Analyze_Call_And_Resolve;
1725 -- Do Analyze and Resolve calls for procedure call. At the end, check
1726 -- for illegal order dependence.
1727 -- ??? where is the check for illegal order dependencies?
1729 ------------------------------
1730 -- Analyze_Call_And_Resolve --
1731 ------------------------------
1733 procedure Analyze_Call_And_Resolve is
1735 if Nkind (N) = N_Procedure_Call_Statement then
1737 Resolve (N, Standard_Void_Type);
1741 end Analyze_Call_And_Resolve;
1745 Actuals : constant List_Id := Parameter_Associations (N);
1746 Loc : constant Source_Ptr := Sloc (N);
1747 P : constant Node_Id := Name (N);
1749 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1750 -- Save the Ghost mode to restore on exit
1755 -- Start of processing for Analyze_Procedure_Call
1758 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1759 -- a procedure call or an entry call. The prefix may denote an access
1760 -- to subprogram type, in which case an implicit dereference applies.
1761 -- If the prefix is an indexed component (without implicit dereference)
1762 -- then the construct denotes a call to a member of an entire family.
1763 -- If the prefix is a simple name, it may still denote a call to a
1764 -- parameterless member of an entry family. Resolution of these various
1765 -- interpretations is delicate.
1767 -- Do not analyze machine code statements to avoid rejecting them in
1770 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1771 Set_Etype (P, Standard_Void_Type);
1776 -- If this is a call of the form Obj.Op, the call may have been analyzed
1777 -- and possibly rewritten into a block, in which case we are done.
1779 if Analyzed (N) then
1782 -- If there is an error analyzing the name (which may have been
1783 -- rewritten if the original call was in prefix notation) then error
1784 -- has been emitted already, mark node and return.
1786 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1787 Set_Etype (N, Any_Type);
1791 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1792 -- Set the mode now to ensure that any nodes generated during analysis
1793 -- and expansion are properly marked as Ghost.
1795 Mark_And_Set_Ghost_Procedure_Call (N);
1797 -- Otherwise analyze the parameters
1799 if Present (Actuals) then
1800 Actual := First (Actuals);
1802 while Present (Actual) loop
1804 Check_Parameterless_Call (Actual);
1809 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1811 if Nkind (P) = N_Attribute_Reference
1812 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1814 Name_Elab_Subp_Body)
1816 if Present (Actuals) then
1818 ("no parameters allowed for this call", First (Actuals));
1822 Set_Etype (N, Standard_Void_Type);
1825 elsif Is_Entity_Name (P)
1826 and then Is_Record_Type (Etype (Entity (P)))
1827 and then Remote_AST_I_Dereference (P)
1831 elsif Is_Entity_Name (P)
1832 and then Ekind (Entity (P)) /= E_Entry_Family
1834 if Is_Access_Type (Etype (P))
1835 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1836 and then No (Actuals)
1837 and then Comes_From_Source (N)
1839 Error_Msg_N ("missing explicit dereference in call", N);
1842 Analyze_Call_And_Resolve;
1844 -- If the prefix is the simple name of an entry family, this is a
1845 -- parameterless call from within the task body itself.
1847 elsif Is_Entity_Name (P)
1848 and then Nkind (P) = N_Identifier
1849 and then Ekind (Entity (P)) = E_Entry_Family
1850 and then Present (Actuals)
1851 and then No (Next (First (Actuals)))
1853 -- Can be call to parameterless entry family. What appears to be the
1854 -- sole argument is in fact the entry index. Rewrite prefix of node
1855 -- accordingly. Source representation is unchanged by this
1859 Make_Indexed_Component (Loc,
1861 Make_Selected_Component (Loc,
1862 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1863 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1864 Expressions => Actuals);
1865 Set_Name (N, New_N);
1866 Set_Etype (New_N, Standard_Void_Type);
1867 Set_Parameter_Associations (N, No_List);
1868 Analyze_Call_And_Resolve;
1870 elsif Nkind (P) = N_Explicit_Dereference then
1871 if Ekind (Etype (P)) = E_Subprogram_Type then
1872 Analyze_Call_And_Resolve;
1874 Error_Msg_N ("expect access to procedure in call", P);
1877 -- The name can be a selected component or an indexed component that
1878 -- yields an access to subprogram. Such a prefix is legal if the call
1879 -- has parameter associations.
1881 elsif Is_Access_Type (Etype (P))
1882 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1884 if Present (Actuals) then
1885 Analyze_Call_And_Resolve;
1887 Error_Msg_N ("missing explicit dereference in call ", N);
1890 -- If not an access to subprogram, then the prefix must resolve to the
1891 -- name of an entry, entry family, or protected operation.
1893 -- For the case of a simple entry call, P is a selected component where
1894 -- the prefix is the task and the selector name is the entry. A call to
1895 -- a protected procedure will have the same syntax. If the protected
1896 -- object contains overloaded operations, the entity may appear as a
1897 -- function, the context will select the operation whose type is Void.
1899 elsif Nkind (P) = N_Selected_Component
1900 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1904 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1905 -- in prefix notation may still be missing its controlling argument,
1906 -- so perform the transformation now.
1908 if SPARK_Mode = On and then In_Inlined_Body then
1910 Subp : constant Entity_Id := Entity (Selector_Name (P));
1911 Typ : constant Entity_Id := Etype (Prefix (P));
1914 if Is_Tagged_Type (Typ)
1915 and then Present (First_Formal (Subp))
1916 and then Etype (First_Formal (Subp)) = Typ
1917 and then Try_Object_Operation (P)
1922 Analyze_Call_And_Resolve;
1927 Analyze_Call_And_Resolve;
1930 elsif Nkind (P) = N_Selected_Component
1931 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1932 and then Present (Actuals)
1933 and then No (Next (First (Actuals)))
1935 -- Can be call to parameterless entry family. What appears to be the
1936 -- sole argument is in fact the entry index. Rewrite prefix of node
1937 -- accordingly. Source representation is unchanged by this
1941 Make_Indexed_Component (Loc,
1942 Prefix => New_Copy (P),
1943 Expressions => Actuals);
1944 Set_Name (N, New_N);
1945 Set_Etype (New_N, Standard_Void_Type);
1946 Set_Parameter_Associations (N, No_List);
1947 Analyze_Call_And_Resolve;
1949 -- For the case of a reference to an element of an entry family, P is
1950 -- an indexed component whose prefix is a selected component (task and
1951 -- entry family), and whose index is the entry family index.
1953 elsif Nkind (P) = N_Indexed_Component
1954 and then Nkind (Prefix (P)) = N_Selected_Component
1955 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1957 Analyze_Call_And_Resolve;
1959 -- If the prefix is the name of an entry family, it is a call from
1960 -- within the task body itself.
1962 elsif Nkind (P) = N_Indexed_Component
1963 and then Nkind (Prefix (P)) = N_Identifier
1964 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1967 Make_Selected_Component (Loc,
1969 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1970 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1971 Rewrite (Prefix (P), New_N);
1973 Analyze_Call_And_Resolve;
1975 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1976 -- procedure name, so the construct can only be a qualified expression.
1978 elsif Nkind (P) = N_Qualified_Expression
1979 and then Ada_Version >= Ada_2012
1981 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1984 -- Anything else is an error
1987 Error_Msg_N ("invalid procedure or entry call", N);
1991 Restore_Ghost_Mode (Saved_GM);
1992 end Analyze_Procedure_Call;
1994 ------------------------------
1995 -- Analyze_Return_Statement --
1996 ------------------------------
1998 procedure Analyze_Return_Statement (N : Node_Id) is
1999 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2000 N_Simple_Return_Statement));
2002 Returns_Object : constant Boolean :=
2003 Nkind (N) = N_Extended_Return_Statement
2005 (Nkind (N) = N_Simple_Return_Statement
2006 and then Present (Expression (N)));
2007 -- True if we're returning something; that is, "return <expression>;"
2008 -- or "return Result : T [:= ...]". False for "return;". Used for error
2009 -- checking: If Returns_Object is True, N should apply to a function
2010 -- body; otherwise N should apply to a procedure body, entry body,
2011 -- accept statement, or extended return statement.
2013 function Find_What_It_Applies_To return Entity_Id;
2014 -- Find the entity representing the innermost enclosing body, accept
2015 -- statement, or extended return statement. If the result is a callable
2016 -- construct or extended return statement, then this will be the value
2017 -- of the Return_Applies_To attribute. Otherwise, the program is
2018 -- illegal. See RM-6.5(4/2).
2020 -----------------------------
2021 -- Find_What_It_Applies_To --
2022 -----------------------------
2024 function Find_What_It_Applies_To return Entity_Id is
2025 Result : Entity_Id := Empty;
2028 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2029 -- and postconditions.
2031 for J in reverse 0 .. Scope_Stack.Last loop
2032 Result := Scope_Stack.Table (J).Entity;
2033 exit when not Ekind_In (Result, E_Block, E_Loop)
2034 and then Chars (Result) /= Name_uPostconditions;
2037 pragma Assert (Present (Result));
2039 end Find_What_It_Applies_To;
2041 -- Local declarations
2043 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2044 Kind : constant Entity_Kind := Ekind (Scope_Id);
2045 Loc : constant Source_Ptr := Sloc (N);
2046 Stm_Entity : constant Entity_Id :=
2048 (E_Return_Statement, Current_Scope, Loc, 'R');
2050 -- Start of processing for Analyze_Return_Statement
2053 Set_Return_Statement_Entity (N, Stm_Entity);
2055 Set_Etype (Stm_Entity, Standard_Void_Type);
2056 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2058 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2059 -- (4/2): an inner return statement will apply to this extended return.
2061 if Nkind (N) = N_Extended_Return_Statement then
2062 Push_Scope (Stm_Entity);
2065 -- Check that pragma No_Return is obeyed. Don't complain about the
2066 -- implicitly-generated return that is placed at the end.
2068 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2069 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2072 -- Warn on any unassigned OUT parameters if in procedure
2074 if Ekind (Scope_Id) = E_Procedure then
2075 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2078 -- Check that functions return objects, and other things do not
2080 if Kind = E_Function or else Kind = E_Generic_Function then
2081 if not Returns_Object then
2082 Error_Msg_N ("missing expression in return from function", N);
2085 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2086 if Returns_Object then
2087 Error_Msg_N ("procedure cannot return value (use function)", N);
2090 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2091 if Returns_Object then
2092 if Is_Protected_Type (Scope (Scope_Id)) then
2093 Error_Msg_N ("entry body cannot return value", N);
2095 Error_Msg_N ("accept statement cannot return value", N);
2099 elsif Kind = E_Return_Statement then
2101 -- We are nested within another return statement, which must be an
2102 -- extended_return_statement.
2104 if Returns_Object then
2105 if Nkind (N) = N_Extended_Return_Statement then
2107 ("extended return statement cannot be nested (use `RETURN;`)",
2110 -- Case of a simple return statement with a value inside extended
2111 -- return statement.
2115 ("return nested in extended return statement cannot return "
2116 & "value (use `RETURN;`)", N);
2121 Error_Msg_N ("illegal context for return statement", N);
2124 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2125 Analyze_Function_Return (N);
2127 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2128 Set_Return_Present (Scope_Id);
2131 if Nkind (N) = N_Extended_Return_Statement then
2135 Kill_Current_Values (Last_Assignment_Only => True);
2136 Check_Unreachable_Code (N);
2138 Analyze_Dimension (N);
2139 end Analyze_Return_Statement;
2141 -------------------------------------
2142 -- Analyze_Simple_Return_Statement --
2143 -------------------------------------
2145 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2147 if Present (Expression (N)) then
2148 Mark_Coextensions (N, Expression (N));
2151 Analyze_Return_Statement (N);
2152 end Analyze_Simple_Return_Statement;
2154 -------------------------
2155 -- Analyze_Return_Type --
2156 -------------------------
2158 procedure Analyze_Return_Type (N : Node_Id) is
2159 Designator : constant Entity_Id := Defining_Entity (N);
2160 Typ : Entity_Id := Empty;
2163 -- Normal case where result definition does not indicate an error
2165 if Result_Definition (N) /= Error then
2166 if Nkind (Result_Definition (N)) = N_Access_Definition then
2167 Check_SPARK_05_Restriction
2168 ("access result is not allowed", Result_Definition (N));
2170 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2173 AD : constant Node_Id :=
2174 Access_To_Subprogram_Definition (Result_Definition (N));
2176 if Present (AD) and then Protected_Present (AD) then
2177 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2179 Typ := Access_Definition (N, Result_Definition (N));
2183 Set_Parent (Typ, Result_Definition (N));
2184 Set_Is_Local_Anonymous_Access (Typ);
2185 Set_Etype (Designator, Typ);
2187 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2189 Null_Exclusion_Static_Checks (N);
2191 -- Subtype_Mark case
2194 Find_Type (Result_Definition (N));
2195 Typ := Entity (Result_Definition (N));
2196 Set_Etype (Designator, Typ);
2198 -- Unconstrained array as result is not allowed in SPARK
2200 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2201 Check_SPARK_05_Restriction
2202 ("returning an unconstrained array is not allowed",
2203 Result_Definition (N));
2206 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2208 Null_Exclusion_Static_Checks (N);
2210 -- If a null exclusion is imposed on the result type, then create
2211 -- a null-excluding itype (an access subtype) and use it as the
2212 -- function's Etype. Note that the null exclusion checks are done
2213 -- right before this, because they don't get applied to types that
2214 -- do not come from source.
2216 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2217 Set_Etype (Designator,
2218 Create_Null_Excluding_Itype
2221 Scope_Id => Scope (Current_Scope)));
2223 -- The new subtype must be elaborated before use because
2224 -- it is visible outside of the function. However its base
2225 -- type may not be frozen yet, so the reference that will
2226 -- force elaboration must be attached to the freezing of
2229 -- If the return specification appears on a proper body,
2230 -- the subtype will have been created already on the spec.
2232 if Is_Frozen (Typ) then
2233 if Nkind (Parent (N)) = N_Subprogram_Body
2234 and then Nkind (Parent (Parent (N))) = N_Subunit
2238 Build_Itype_Reference (Etype (Designator), Parent (N));
2242 Ensure_Freeze_Node (Typ);
2245 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2247 Set_Itype (IR, Etype (Designator));
2248 Append_Freeze_Actions (Typ, New_List (IR));
2253 Set_Etype (Designator, Typ);
2256 if Ekind (Typ) = E_Incomplete_Type
2257 or else (Is_Class_Wide_Type (Typ)
2258 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2260 -- AI05-0151: Tagged incomplete types are allowed in all formal
2261 -- parts. Untagged incomplete types are not allowed in bodies.
2262 -- As a consequence, limited views cannot appear in a basic
2263 -- declaration that is itself within a body, because there is
2264 -- no point at which the non-limited view will become visible.
2266 if Ada_Version >= Ada_2012 then
2267 if From_Limited_With (Typ) and then In_Package_Body then
2269 ("invalid use of incomplete type&",
2270 Result_Definition (N), Typ);
2272 -- The return type of a subprogram body cannot be of a
2273 -- formal incomplete type.
2275 elsif Is_Generic_Type (Typ)
2276 and then Nkind (Parent (N)) = N_Subprogram_Body
2279 ("return type cannot be a formal incomplete type",
2280 Result_Definition (N));
2282 elsif Is_Class_Wide_Type (Typ)
2283 and then Is_Generic_Type (Root_Type (Typ))
2284 and then Nkind (Parent (N)) = N_Subprogram_Body
2287 ("return type cannot be a formal incomplete type",
2288 Result_Definition (N));
2290 elsif Is_Tagged_Type (Typ) then
2293 -- Use is legal in a thunk generated for an operation
2294 -- inherited from a progenitor.
2296 elsif Is_Thunk (Designator)
2297 and then Present (Non_Limited_View (Typ))
2301 elsif Nkind (Parent (N)) = N_Subprogram_Body
2302 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2306 ("invalid use of untagged incomplete type&",
2310 -- The type must be completed in the current package. This
2311 -- is checked at the end of the package declaration when
2312 -- Taft-amendment types are identified. If the return type
2313 -- is class-wide, there is no required check, the type can
2314 -- be a bona fide TAT.
2316 if Ekind (Scope (Current_Scope)) = E_Package
2317 and then In_Private_Part (Scope (Current_Scope))
2318 and then not Is_Class_Wide_Type (Typ)
2320 Append_Elmt (Designator, Private_Dependents (Typ));
2325 ("invalid use of incomplete type&", Designator, Typ);
2330 -- Case where result definition does indicate an error
2333 Set_Etype (Designator, Any_Type);
2335 end Analyze_Return_Type;
2337 -----------------------------
2338 -- Analyze_Subprogram_Body --
2339 -----------------------------
2341 procedure Analyze_Subprogram_Body (N : Node_Id) is
2342 Loc : constant Source_Ptr := Sloc (N);
2343 Body_Spec : constant Node_Id := Specification (N);
2344 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2347 if Debug_Flag_C then
2348 Write_Str ("==> subprogram body ");
2349 Write_Name (Chars (Body_Id));
2350 Write_Str (" from ");
2351 Write_Location (Loc);
2356 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2358 -- The real work is split out into the helper, so it can do "return;"
2359 -- without skipping the debug output:
2361 Analyze_Subprogram_Body_Helper (N);
2363 if Debug_Flag_C then
2365 Write_Str ("<== subprogram body ");
2366 Write_Name (Chars (Body_Id));
2367 Write_Str (" from ");
2368 Write_Location (Loc);
2371 end Analyze_Subprogram_Body;
2373 ------------------------------------
2374 -- Analyze_Subprogram_Body_Helper --
2375 ------------------------------------
2377 -- This procedure is called for regular subprogram bodies, generic bodies,
2378 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2379 -- specification matters, and is used to create a proper declaration for
2380 -- the subprogram, or to perform conformance checks.
2382 -- WARNING: This routine manages Ghost regions. Return statements must be
2383 -- replaced by gotos which jump to the end of the routine and restore the
2386 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2387 Body_Spec : Node_Id := Specification (N);
2388 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2389 Loc : constant Source_Ptr := Sloc (N);
2390 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2392 Conformant : Boolean;
2393 Desig_View : Entity_Id := Empty;
2394 Exch_Views : Elist_Id := No_Elist;
2396 Mask_Types : Elist_Id := No_Elist;
2397 Prot_Typ : Entity_Id := Empty;
2398 Spec_Decl : Node_Id := Empty;
2399 Spec_Id : Entity_Id;
2401 Last_Real_Spec_Entity : Entity_Id := Empty;
2402 -- When we analyze a separate spec, the entity chain ends up containing
2403 -- the formals, as well as any itypes generated during analysis of the
2404 -- default expressions for parameters, or the arguments of associated
2405 -- precondition/postcondition pragmas (which are analyzed in the context
2406 -- of the spec since they have visibility on formals).
2408 -- These entities belong with the spec and not the body. However we do
2409 -- the analysis of the body in the context of the spec (again to obtain
2410 -- visibility to the formals), and all the entities generated during
2411 -- this analysis end up also chained to the entity chain of the spec.
2412 -- But they really belong to the body, and there is circuitry to move
2413 -- them from the spec to the body.
2415 -- However, when we do this move, we don't want to move the real spec
2416 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2417 -- variable points to the last real spec entity, so we only move those
2418 -- chained beyond that point. It is initialized to Empty to deal with
2419 -- the case where there is no separate spec.
2421 function Body_Has_Contract return Boolean;
2422 -- Check whether unanalyzed body has an aspect or pragma that may
2423 -- generate a SPARK contract.
2425 function Body_Has_SPARK_Mode_On return Boolean;
2426 -- Check whether SPARK_Mode On applies to the subprogram body, either
2427 -- because it is specified directly on the body, or because it is
2428 -- inherited from the enclosing subprogram or package.
2430 procedure Build_Subprogram_Declaration;
2431 -- Create a matching subprogram declaration for subprogram body N
2433 procedure Check_Anonymous_Return;
2434 -- Ada 2005: if a function returns an access type that denotes a task,
2435 -- or a type that contains tasks, we must create a master entity for
2436 -- the anonymous type, which typically will be used in an allocator
2437 -- in the body of the function.
2439 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2440 -- Look ahead to recognize a pragma that may appear after the body.
2441 -- If there is a previous spec, check that it appears in the same
2442 -- declarative part. If the pragma is Inline_Always, perform inlining
2443 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2444 -- If the body acts as a spec, and inlining is required, we create a
2445 -- subprogram declaration for it, in order to attach the body to inline.
2446 -- If pragma does not appear after the body, check whether there is
2447 -- an inline pragma before any local declarations.
2449 procedure Check_Missing_Return;
2450 -- Checks for a function with a no return statements, and also performs
2451 -- the warning checks implemented by Check_Returns. In formal mode, also
2452 -- verify that a function ends with a RETURN and that a procedure does
2453 -- not contain any RETURN.
2455 function Disambiguate_Spec return Entity_Id;
2456 -- When a primitive is declared between the private view and the full
2457 -- view of a concurrent type which implements an interface, a special
2458 -- mechanism is used to find the corresponding spec of the primitive
2461 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2462 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2463 -- incomplete types coming from a limited context and replace their
2464 -- limited views with the non-limited ones. Return the list of changes
2465 -- to be used to undo the transformation.
2467 function Is_Private_Concurrent_Primitive
2468 (Subp_Id : Entity_Id) return Boolean;
2469 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2470 -- type that implements an interface and has a private view.
2472 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2473 -- N is the body generated for an expression function that is not a
2474 -- completion and Spec_Id the defining entity of its spec. Mark all
2475 -- the not-yet-frozen types referenced by the simple return statement
2476 -- of the function as formally frozen.
2478 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2479 -- Undo the transformation done by Exchange_Limited_Views.
2481 procedure Set_Trivial_Subprogram (N : Node_Id);
2482 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2483 -- subprogram whose body is being analyzed. N is the statement node
2484 -- causing the flag to be set, if the following statement is a return
2485 -- of an entity, we mark the entity as set in source to suppress any
2486 -- warning on the stylized use of function stubs with a dummy return.
2488 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2489 -- Undo the transformation done by Mask_Unfrozen_Types
2491 procedure Verify_Overriding_Indicator;
2492 -- If there was a previous spec, the entity has been entered in the
2493 -- current scope previously. If the body itself carries an overriding
2494 -- indicator, check that it is consistent with the known status of the
2497 -----------------------
2498 -- Body_Has_Contract --
2499 -----------------------
2501 function Body_Has_Contract return Boolean is
2502 Decls : constant List_Id := Declarations (N);
2506 -- Check for aspects that may generate a contract
2508 if Present (Aspect_Specifications (N)) then
2509 Item := First (Aspect_Specifications (N));
2510 while Present (Item) loop
2511 if Is_Subprogram_Contract_Annotation (Item) then
2519 -- Check for pragmas that may generate a contract
2521 if Present (Decls) then
2522 Item := First (Decls);
2523 while Present (Item) loop
2524 if Nkind (Item) = N_Pragma
2525 and then Is_Subprogram_Contract_Annotation (Item)
2535 end Body_Has_Contract;
2537 ----------------------------
2538 -- Body_Has_SPARK_Mode_On --
2539 ----------------------------
2541 function Body_Has_SPARK_Mode_On return Boolean is
2542 Decls : constant List_Id := Declarations (N);
2546 -- Check for SPARK_Mode aspect
2548 if Present (Aspect_Specifications (N)) then
2549 Item := First (Aspect_Specifications (N));
2550 while Present (Item) loop
2551 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2552 return Get_SPARK_Mode_From_Annotation (Item) = On;
2559 -- Check for SPARK_Mode pragma
2561 if Present (Decls) then
2562 Item := First (Decls);
2563 while Present (Item) loop
2565 -- Pragmas that apply to a subprogram body are usually grouped
2566 -- together. Look for a potential pragma SPARK_Mode among them.
2568 if Nkind (Item) = N_Pragma then
2569 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2570 return Get_SPARK_Mode_From_Annotation (Item) = On;
2573 -- Otherwise the first non-pragma declarative item terminates
2574 -- the region where pragma SPARK_Mode may appear.
2584 -- Otherwise, the applicable SPARK_Mode is inherited from the
2585 -- enclosing subprogram or package.
2587 return SPARK_Mode = On;
2588 end Body_Has_SPARK_Mode_On;
2590 ----------------------------------
2591 -- Build_Subprogram_Declaration --
2592 ----------------------------------
2594 procedure Build_Subprogram_Declaration is
2595 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2596 -- Relocate certain categorization pragmas from the declarative list
2597 -- of subprogram body From and insert them after node To. The pragmas
2600 -- Volatile_Function
2601 -- Also copy pragma SPARK_Mode if present in the declarative list
2602 -- of subprogram body From and insert it after node To. This pragma
2603 -- should not be moved, as it applies to the body too.
2609 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2611 Next_Decl : Node_Id;
2614 pragma Assert (Nkind (From) = N_Subprogram_Body);
2616 -- The destination node must be part of a list, as the pragmas are
2617 -- inserted after it.
2619 pragma Assert (Is_List_Member (To));
2621 -- Inspect the declarations of the subprogram body looking for
2622 -- specific pragmas.
2624 Decl := First (Declarations (N));
2625 while Present (Decl) loop
2626 Next_Decl := Next (Decl);
2628 if Nkind (Decl) = N_Pragma then
2629 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2630 Insert_After (To, New_Copy_Tree (Decl));
2632 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2634 Name_Volatile_Function)
2637 Insert_After (To, Decl);
2648 Subp_Decl : Node_Id;
2650 -- Start of processing for Build_Subprogram_Declaration
2653 -- Create a matching subprogram spec using the profile of the body.
2654 -- The structure of the tree is identical, but has new entities for
2655 -- the defining unit name and formal parameters.
2658 Make_Subprogram_Declaration (Loc,
2659 Specification => Copy_Subprogram_Spec (Body_Spec));
2660 Set_Comes_From_Source (Subp_Decl, True);
2662 -- Relocate the aspects and relevant pragmas from the subprogram body
2663 -- to the generated spec because it acts as the initial declaration.
2665 Insert_Before (N, Subp_Decl);
2666 Move_Aspects (N, To => Subp_Decl);
2667 Move_Pragmas (N, To => Subp_Decl);
2669 -- Ensure that the generated corresponding spec and original body
2670 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2671 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2672 -- correctly set for local subprograms.
2674 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2676 Analyze (Subp_Decl);
2678 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2679 -- the body since the expander may generate calls using that entity.
2680 -- Required to ensure that Expand_Call rewrites calls to this
2681 -- function by calls to the built procedure.
2683 if Modify_Tree_For_C
2684 and then Nkind (Body_Spec) = N_Function_Specification
2686 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2688 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2689 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2690 Corresponding_Procedure
2691 (Defining_Entity (Specification (Subp_Decl))));
2694 -- Analyze any relocated source pragmas or pragmas created for aspect
2697 Decl := Next (Subp_Decl);
2698 while Present (Decl) loop
2700 -- Stop the search for pragmas once the body has been reached as
2701 -- this terminates the region where pragmas may appear.
2706 elsif Nkind (Decl) = N_Pragma then
2713 Spec_Id := Defining_Entity (Subp_Decl);
2714 Set_Corresponding_Spec (N, Spec_Id);
2716 -- Mark the generated spec as a source construct to ensure that all
2717 -- calls to it are properly registered in ALI files for GNATprove.
2719 Set_Comes_From_Source (Spec_Id, True);
2721 -- Ensure that the specs of the subprogram declaration and its body
2722 -- are identical, otherwise they will appear non-conformant due to
2723 -- rewritings in the default values of formal parameters.
2725 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2726 Set_Specification (N, Body_Spec);
2727 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2728 end Build_Subprogram_Declaration;
2730 ----------------------------
2731 -- Check_Anonymous_Return --
2732 ----------------------------
2734 procedure Check_Anonymous_Return is
2740 if Present (Spec_Id) then
2746 if Ekind (Scop) = E_Function
2747 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2748 and then not Is_Thunk (Scop)
2750 -- Skip internally built functions which handle the case of
2751 -- a null access (see Expand_Interface_Conversion)
2753 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2754 and then not Comes_From_Source (Parent (Scop)))
2756 and then (Has_Task (Designated_Type (Etype (Scop)))
2758 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2760 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2761 and then Expander_Active
2763 -- Avoid cases with no tasking support
2765 and then RTE_Available (RE_Current_Master)
2766 and then not Restriction_Active (No_Task_Hierarchy)
2769 Make_Object_Declaration (Loc,
2770 Defining_Identifier =>
2771 Make_Defining_Identifier (Loc, Name_uMaster),
2772 Constant_Present => True,
2773 Object_Definition =>
2774 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2776 Make_Explicit_Dereference (Loc,
2777 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2779 if Present (Declarations (N)) then
2780 Prepend (Decl, Declarations (N));
2782 Set_Declarations (N, New_List (Decl));
2785 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2786 Set_Has_Master_Entity (Scop);
2788 -- Now mark the containing scope as a task master
2791 while Nkind (Par) /= N_Compilation_Unit loop
2792 Par := Parent (Par);
2793 pragma Assert (Present (Par));
2795 -- If we fall off the top, we are at the outer level, and
2796 -- the environment task is our effective master, so nothing
2800 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2802 Set_Is_Task_Master (Par, True);
2807 end Check_Anonymous_Return;
2809 -------------------------
2810 -- Check_Inline_Pragma --
2811 -------------------------
2813 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2817 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2818 -- True when N is a pragma Inline or Inline_Always that applies
2819 -- to this subprogram.
2821 -----------------------
2822 -- Is_Inline_Pragma --
2823 -----------------------
2825 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2827 if Nkind (N) = N_Pragma
2829 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2830 or else (Pragma_Name_Unmapped (N) = Name_Inline
2832 (Front_End_Inlining or else Optimization_Level > 0)))
2833 and then Present (Pragma_Argument_Associations (N))
2836 Pragma_Arg : Node_Id :=
2837 Expression (First (Pragma_Argument_Associations (N)));
2839 if Nkind (Pragma_Arg) = N_Selected_Component then
2840 Pragma_Arg := Selector_Name (Pragma_Arg);
2843 return Chars (Pragma_Arg) = Chars (Body_Id);
2849 end Is_Inline_Pragma;
2851 -- Start of processing for Check_Inline_Pragma
2854 if not Expander_Active then
2858 if Is_List_Member (N)
2859 and then Present (Next (N))
2860 and then Is_Inline_Pragma (Next (N))
2864 elsif Nkind (N) /= N_Subprogram_Body_Stub
2865 and then Present (Declarations (N))
2866 and then Is_Inline_Pragma (First (Declarations (N)))
2868 Prag := First (Declarations (N));
2874 if Present (Prag) then
2875 if Present (Spec_Id) then
2876 if Is_List_Member (N)
2877 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2878 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2884 -- Create a subprogram declaration, to make treatment uniform.
2885 -- Make the sloc of the subprogram name that of the entity in
2886 -- the body, so that style checks find identical strings.
2889 Subp : constant Entity_Id :=
2890 Make_Defining_Identifier
2891 (Sloc (Body_Id), Chars (Body_Id));
2892 Decl : constant Node_Id :=
2893 Make_Subprogram_Declaration (Loc,
2895 New_Copy_Tree (Specification (N)));
2898 -- Link the body and the generated spec
2900 Set_Corresponding_Body (Decl, Body_Id);
2901 Set_Corresponding_Spec (N, Subp);
2903 Set_Defining_Unit_Name (Specification (Decl), Subp);
2905 -- To ensure proper coverage when body is inlined, indicate
2906 -- whether the subprogram comes from source.
2908 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2910 if Present (First_Formal (Body_Id)) then
2911 Plist := Copy_Parameter_List (Body_Id);
2912 Set_Parameter_Specifications
2913 (Specification (Decl), Plist);
2916 -- Move aspects to the new spec
2918 if Has_Aspects (N) then
2919 Move_Aspects (N, To => Decl);
2922 Insert_Before (N, Decl);
2925 Set_Has_Pragma_Inline (Subp);
2927 if Pragma_Name (Prag) = Name_Inline_Always then
2928 Set_Is_Inlined (Subp);
2929 Set_Has_Pragma_Inline_Always (Subp);
2932 -- Prior to copying the subprogram body to create a template
2933 -- for it for subsequent inlining, remove the pragma from
2934 -- the current body so that the copy that will produce the
2935 -- new body will start from a completely unanalyzed tree.
2937 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2938 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2945 end Check_Inline_Pragma;
2947 --------------------------
2948 -- Check_Missing_Return --
2949 --------------------------
2951 procedure Check_Missing_Return is
2953 Missing_Ret : Boolean;
2956 if Nkind (Body_Spec) = N_Function_Specification then
2957 if Present (Spec_Id) then
2963 if Return_Present (Id) then
2964 Check_Returns (HSS, 'F', Missing_Ret);
2967 Set_Has_Missing_Return (Id);
2970 -- Within a premature instantiation of a package with no body, we
2971 -- build completions of the functions therein, with a Raise
2972 -- statement. No point in complaining about a missing return in
2975 elsif Ekind (Id) = E_Function
2976 and then In_Instance
2977 and then Present (Statements (HSS))
2978 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2982 elsif Is_Generic_Subprogram (Id)
2983 or else not Is_Machine_Code_Subprogram (Id)
2985 Error_Msg_N ("missing RETURN statement in function body", N);
2988 -- If procedure with No_Return, check returns
2990 elsif Nkind (Body_Spec) = N_Procedure_Specification
2991 and then Present (Spec_Id)
2992 and then No_Return (Spec_Id)
2994 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2997 -- Special checks in SPARK mode
2999 if Nkind (Body_Spec) = N_Function_Specification then
3001 -- In SPARK mode, last statement of a function should be a return
3004 Stat : constant Node_Id := Last_Source_Statement (HSS);
3007 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3008 N_Extended_Return_Statement)
3010 Check_SPARK_05_Restriction
3011 ("last statement in function should be RETURN", Stat);
3015 -- In SPARK mode, verify that a procedure has no return
3017 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3018 if Present (Spec_Id) then
3024 -- Would be nice to point to return statement here, can we
3025 -- borrow the Check_Returns procedure here ???
3027 if Return_Present (Id) then
3028 Check_SPARK_05_Restriction
3029 ("procedure should not have RETURN", N);
3032 end Check_Missing_Return;
3034 -----------------------
3035 -- Disambiguate_Spec --
3036 -----------------------
3038 function Disambiguate_Spec return Entity_Id is
3039 Priv_Spec : Entity_Id;
3042 procedure Replace_Types (To_Corresponding : Boolean);
3043 -- Depending on the flag, replace the type of formal parameters of
3044 -- Body_Id if it is a concurrent type implementing interfaces with
3045 -- the corresponding record type or the other way around.
3047 procedure Replace_Types (To_Corresponding : Boolean) is
3049 Formal_Typ : Entity_Id;
3052 Formal := First_Formal (Body_Id);
3053 while Present (Formal) loop
3054 Formal_Typ := Etype (Formal);
3056 if Is_Class_Wide_Type (Formal_Typ) then
3057 Formal_Typ := Root_Type (Formal_Typ);
3060 -- From concurrent type to corresponding record
3062 if To_Corresponding then
3063 if Is_Concurrent_Type (Formal_Typ)
3064 and then Present (Corresponding_Record_Type (Formal_Typ))
3067 (Corresponding_Record_Type (Formal_Typ)))
3070 Corresponding_Record_Type (Formal_Typ));
3073 -- From corresponding record to concurrent type
3076 if Is_Concurrent_Record_Type (Formal_Typ)
3077 and then Present (Interfaces (Formal_Typ))
3080 Corresponding_Concurrent_Type (Formal_Typ));
3084 Next_Formal (Formal);
3088 -- Start of processing for Disambiguate_Spec
3091 -- Try to retrieve the specification of the body as is. All error
3092 -- messages are suppressed because the body may not have a spec in
3093 -- its current state.
3095 Spec_N := Find_Corresponding_Spec (N, False);
3097 -- It is possible that this is the body of a primitive declared
3098 -- between a private and a full view of a concurrent type. The
3099 -- controlling parameter of the spec carries the concurrent type,
3100 -- not the corresponding record type as transformed by Analyze_
3101 -- Subprogram_Specification. In such cases, we undo the change
3102 -- made by the analysis of the specification and try to find the
3105 -- Note that wrappers already have their corresponding specs and
3106 -- bodies set during their creation, so if the candidate spec is
3107 -- a wrapper, then we definitely need to swap all types to their
3108 -- original concurrent status.
3111 or else Is_Primitive_Wrapper (Spec_N)
3113 -- Restore all references of corresponding record types to the
3114 -- original concurrent types.
3116 Replace_Types (To_Corresponding => False);
3117 Priv_Spec := Find_Corresponding_Spec (N, False);
3119 -- The current body truly belongs to a primitive declared between
3120 -- a private and a full view. We leave the modified body as is,
3121 -- and return the true spec.
3123 if Present (Priv_Spec)
3124 and then Is_Private_Primitive (Priv_Spec)
3129 -- In case that this is some sort of error, restore the original
3130 -- state of the body.
3132 Replace_Types (To_Corresponding => True);
3136 end Disambiguate_Spec;
3138 ----------------------------
3139 -- Exchange_Limited_Views --
3140 ----------------------------
3142 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3143 Result : Elist_Id := No_Elist;
3145 procedure Detect_And_Exchange (Id : Entity_Id);
3146 -- Determine whether Id's type denotes an incomplete type associated
3147 -- with a limited with clause and exchange the limited view with the
3148 -- non-limited one when available. Note that the non-limited view
3149 -- may exist because of a with_clause in another unit in the context,
3150 -- but cannot be used because the current view of the enclosing unit
3151 -- is still a limited view.
3153 -------------------------
3154 -- Detect_And_Exchange --
3155 -------------------------
3157 procedure Detect_And_Exchange (Id : Entity_Id) is
3158 Typ : constant Entity_Id := Etype (Id);
3160 if From_Limited_With (Typ)
3161 and then Has_Non_Limited_View (Typ)
3162 and then not From_Limited_With (Scope (Typ))
3165 Result := New_Elmt_List;
3168 Prepend_Elmt (Typ, Result);
3169 Prepend_Elmt (Id, Result);
3170 Set_Etype (Id, Non_Limited_View (Typ));
3172 end Detect_And_Exchange;
3178 -- Start of processing for Exchange_Limited_Views
3181 -- Do not process subprogram bodies as they already use the non-
3182 -- limited view of types.
3184 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3188 -- Examine all formals and swap views when applicable
3190 Formal := First_Formal (Subp_Id);
3191 while Present (Formal) loop
3192 Detect_And_Exchange (Formal);
3194 Next_Formal (Formal);
3197 -- Process the return type of a function
3199 if Ekind (Subp_Id) = E_Function then
3200 Detect_And_Exchange (Subp_Id);
3204 end Exchange_Limited_Views;
3206 -------------------------------------
3207 -- Is_Private_Concurrent_Primitive --
3208 -------------------------------------
3210 function Is_Private_Concurrent_Primitive
3211 (Subp_Id : Entity_Id) return Boolean
3213 Formal_Typ : Entity_Id;
3216 if Present (First_Formal (Subp_Id)) then
3217 Formal_Typ := Etype (First_Formal (Subp_Id));
3219 if Is_Concurrent_Record_Type (Formal_Typ) then
3220 if Is_Class_Wide_Type (Formal_Typ) then
3221 Formal_Typ := Root_Type (Formal_Typ);
3224 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3227 -- The type of the first formal is a concurrent tagged type with
3231 Is_Concurrent_Type (Formal_Typ)
3232 and then Is_Tagged_Type (Formal_Typ)
3233 and then Has_Private_Declaration (Formal_Typ);
3237 end Is_Private_Concurrent_Primitive;
3239 -------------------------
3240 -- Mask_Unfrozen_Types --
3241 -------------------------
3243 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3244 Result : Elist_Id := No_Elist;
3246 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3247 -- Mask all types referenced in the subtree rooted at Node
3249 --------------------
3250 -- Mask_Type_Refs --
3251 --------------------
3253 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3254 procedure Mask_Type (Typ : Entity_Id);
3255 -- ??? what does this do?
3261 procedure Mask_Type (Typ : Entity_Id) is
3263 -- Skip Itypes created by the preanalysis
3266 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3271 if not Is_Frozen (Typ) then
3272 Set_Is_Frozen (Typ);
3273 Append_New_Elmt (Typ, Result);
3277 -- Start of processing for Mask_Type_Refs
3280 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3281 Mask_Type (Etype (Entity (Node)));
3283 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3284 Mask_Type (Scope (Entity (Node)));
3287 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3288 and then Present (Etype (Node))
3290 Mask_Type (Etype (Node));
3296 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3300 Return_Stmt : constant Node_Id :=
3301 First (Statements (Handled_Statement_Sequence (N)));
3303 -- Start of processing for Mask_Unfrozen_Types
3306 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3308 Mask_References (Expression (Return_Stmt));
3311 end Mask_Unfrozen_Types;
3313 ---------------------------
3314 -- Restore_Limited_Views --
3315 ---------------------------
3317 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3318 Elmt : Elmt_Id := First_Elmt (Restore_List);
3322 while Present (Elmt) loop
3325 Set_Etype (Id, Node (Elmt));
3328 end Restore_Limited_Views;
3330 ----------------------------
3331 -- Set_Trivial_Subprogram --
3332 ----------------------------
3334 procedure Set_Trivial_Subprogram (N : Node_Id) is
3335 Nxt : constant Node_Id := Next (N);
3338 Set_Is_Trivial_Subprogram (Body_Id);
3340 if Present (Spec_Id) then
3341 Set_Is_Trivial_Subprogram (Spec_Id);
3345 and then Nkind (Nxt) = N_Simple_Return_Statement
3346 and then No (Next (Nxt))
3347 and then Present (Expression (Nxt))
3348 and then Is_Entity_Name (Expression (Nxt))
3350 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3352 end Set_Trivial_Subprogram;
3354 ---------------------------
3355 -- Unmask_Unfrozen_Types --
3356 ---------------------------
3358 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3359 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3362 while Present (Elmt) loop
3363 Set_Is_Frozen (Node (Elmt), False);
3366 end Unmask_Unfrozen_Types;
3368 ---------------------------------
3369 -- Verify_Overriding_Indicator --
3370 ---------------------------------
3372 procedure Verify_Overriding_Indicator is
3374 if Must_Override (Body_Spec) then
3375 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3376 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3380 elsif not Present (Overridden_Operation (Spec_Id)) then
3382 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3384 -- Overriding indicators aren't allowed for protected subprogram
3385 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3386 -- this to a warning if -gnatd.E is enabled.
3388 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3389 Error_Msg_Warn := Error_To_Warning;
3391 ("<<overriding indicator not allowed for protected "
3392 & "subprogram body", Body_Spec);
3395 elsif Must_Not_Override (Body_Spec) then
3396 if Present (Overridden_Operation (Spec_Id)) then
3398 ("subprogram& overrides inherited operation",
3399 Body_Spec, Spec_Id);
3401 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3402 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3405 ("subprogram& overrides predefined operator ",
3406 Body_Spec, Spec_Id);
3408 -- Overriding indicators aren't allowed for protected subprogram
3409 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3410 -- this to a warning if -gnatd.E is enabled.
3412 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3413 Error_Msg_Warn := Error_To_Warning;
3416 ("<<overriding indicator not allowed "
3417 & "for protected subprogram body", Body_Spec);
3419 -- If this is not a primitive operation, then the overriding
3420 -- indicator is altogether illegal.
3422 elsif not Is_Primitive (Spec_Id) then
3424 ("overriding indicator only allowed "
3425 & "if subprogram is primitive", Body_Spec);
3428 -- If checking the style rule and the operation overrides, then
3429 -- issue a warning about a missing overriding_indicator. Protected
3430 -- subprogram bodies are excluded from this style checking, since
3431 -- they aren't primitives (even though their declarations can
3432 -- override) and aren't allowed to have an overriding_indicator.
3435 and then Present (Overridden_Operation (Spec_Id))
3436 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3438 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3439 Style.Missing_Overriding (N, Body_Id);
3442 and then Can_Override_Operator (Spec_Id)
3443 and then not In_Predefined_Unit (Spec_Id)
3445 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3446 Style.Missing_Overriding (N, Body_Id);
3448 end Verify_Overriding_Indicator;
3452 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3453 Saved_ISMP : constant Boolean :=
3454 Ignore_SPARK_Mode_Pragmas_In_Instance;
3455 -- Save the Ghost and SPARK mode-related data to restore on exit
3457 -- Start of processing for Analyze_Subprogram_Body_Helper
3460 -- A [generic] subprogram body "freezes" the contract of the nearest
3461 -- enclosing package body and all other contracts encountered in the
3462 -- same declarative part up to and excluding the subprogram body:
3464 -- package body Nearest_Enclosing_Package
3465 -- with Refined_State => (State => Constit)
3469 -- procedure Freezes_Enclosing_Package_Body
3470 -- with Refined_Depends => (Input => Constit) ...
3472 -- This ensures that any annotations referenced by the contract of the
3473 -- [generic] subprogram body are available. This form of "freezing" is
3474 -- decoupled from the usual Freeze_xxx mechanism because it must also
3475 -- work in the context of generics where normal freezing is disabled.
3477 -- Only bodies coming from source should cause this type of "freezing".
3478 -- Expression functions that act as bodies and complete an initial
3479 -- declaration must be included in this category, hence the use of
3482 if Comes_From_Source (Original_Node (N)) then
3483 Analyze_Previous_Contracts (N);
3486 -- Generic subprograms are handled separately. They always have a
3487 -- generic specification. Determine whether current scope has a
3488 -- previous declaration.
3490 -- If the subprogram body is defined within an instance of the same
3491 -- name, the instance appears as a package renaming, and will be hidden
3492 -- within the subprogram.
3494 if Present (Prev_Id)
3495 and then not Is_Overloadable (Prev_Id)
3496 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3497 or else Comes_From_Source (Prev_Id))
3499 if Is_Generic_Subprogram (Prev_Id) then
3502 -- A subprogram body is Ghost when it is stand alone and subject
3503 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3504 -- the mode now to ensure that any nodes generated during analysis
3505 -- and expansion are properly marked as Ghost.
3507 Mark_And_Set_Ghost_Body (N, Spec_Id);
3509 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3510 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3512 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3514 if Nkind (N) = N_Subprogram_Body then
3515 HSS := Handled_Statement_Sequence (N);
3516 Check_Missing_Return;
3521 -- Otherwise a previous entity conflicts with the subprogram name.
3522 -- Attempting to enter name will post error.
3525 Enter_Name (Body_Id);
3529 -- Non-generic case, find the subprogram declaration, if one was seen,
3530 -- or enter new overloaded entity in the current scope. If the
3531 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3532 -- part of the context of one of its subunits. No need to redo the
3535 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3539 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3541 if Nkind (N) = N_Subprogram_Body_Stub
3542 or else No (Corresponding_Spec (N))
3544 if Is_Private_Concurrent_Primitive (Body_Id) then
3545 Spec_Id := Disambiguate_Spec;
3547 -- A subprogram body is Ghost when it is stand alone and
3548 -- subject to pragma Ghost or when the corresponding spec is
3549 -- Ghost. Set the mode now to ensure that any nodes generated
3550 -- during analysis and expansion are properly marked as Ghost.
3552 Mark_And_Set_Ghost_Body (N, Spec_Id);
3555 Spec_Id := Find_Corresponding_Spec (N);
3557 -- A subprogram body is Ghost when it is stand alone and
3558 -- subject to pragma Ghost or when the corresponding spec is
3559 -- Ghost. Set the mode now to ensure that any nodes generated
3560 -- during analysis and expansion are properly marked as Ghost.
3562 Mark_And_Set_Ghost_Body (N, Spec_Id);
3564 -- In GNATprove mode, if the body has no previous spec, create
3565 -- one so that the inlining machinery can operate properly.
3566 -- Transfer aspects, if any, to the new spec, so that they
3567 -- are legal and can be processed ahead of the body.
3568 -- We make two copies of the given spec, one for the new
3569 -- declaration, and one for the body.
3571 if No (Spec_Id) and then GNATprove_Mode
3573 -- Inlining does not apply during pre-analysis of code
3575 and then Full_Analysis
3577 -- Inlining only applies to full bodies, not stubs
3579 and then Nkind (N) /= N_Subprogram_Body_Stub
3581 -- Inlining only applies to bodies in the source code, not to
3582 -- those generated by the compiler. In particular, expression
3583 -- functions, whose body is generated by the compiler, are
3584 -- treated specially by GNATprove.
3586 and then Comes_From_Source (Body_Id)
3588 -- This cannot be done for a compilation unit, which is not
3589 -- in a context where we can insert a new spec.
3591 and then Is_List_Member (N)
3593 -- Inlining only applies to subprograms without contracts,
3594 -- as a contract is a sign that GNATprove should perform a
3595 -- modular analysis of the subprogram instead of a contextual
3596 -- analysis at each call site. The same test is performed in
3597 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3598 -- here in another form (because the contract has not been
3599 -- attached to the body) to avoid front-end errors in case
3600 -- pragmas are used instead of aspects, because the
3601 -- corresponding pragmas in the body would not be transferred
3602 -- to the spec, leading to legality errors.
3604 and then not Body_Has_Contract
3605 and then not Inside_A_Generic
3607 Build_Subprogram_Declaration;
3609 -- If this is a function that returns a constrained array, and
3610 -- we are generating SPARK_For_C, create subprogram declaration
3611 -- to simplify subsequent C generation.
3614 and then Modify_Tree_For_C
3615 and then Nkind (Body_Spec) = N_Function_Specification
3616 and then Is_Array_Type (Etype (Body_Id))
3617 and then Is_Constrained (Etype (Body_Id))
3619 Build_Subprogram_Declaration;
3623 -- If this is a duplicate body, no point in analyzing it
3625 if Error_Posted (N) then
3629 -- A subprogram body should cause freezing of its own declaration,
3630 -- but if there was no previous explicit declaration, then the
3631 -- subprogram will get frozen too late (there may be code within
3632 -- the body that depends on the subprogram having been frozen,
3633 -- such as uses of extra formals), so we force it to be frozen
3634 -- here. Same holds if the body and spec are compilation units.
3635 -- Finally, if the return type is an anonymous access to protected
3636 -- subprogram, it must be frozen before the body because its
3637 -- expansion has generated an equivalent type that is used when
3638 -- elaborating the body.
3640 -- An exception in the case of Ada 2012, AI05-177: The bodies
3641 -- created for expression functions do not freeze.
3644 and then Nkind (Original_Node (N)) /= N_Expression_Function
3646 Freeze_Before (N, Body_Id);
3648 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3649 Freeze_Before (N, Spec_Id);
3651 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3652 Freeze_Before (N, Etype (Body_Id));
3656 Spec_Id := Corresponding_Spec (N);
3658 -- A subprogram body is Ghost when it is stand alone and subject
3659 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3660 -- the mode now to ensure that any nodes generated during analysis
3661 -- and expansion are properly marked as Ghost.
3663 Mark_And_Set_Ghost_Body (N, Spec_Id);
3667 -- Previously we scanned the body to look for nested subprograms, and
3668 -- rejected an inline directive if nested subprograms were present,
3669 -- because the back-end would generate conflicting symbols for the
3670 -- nested bodies. This is now unnecessary.
3672 -- Look ahead to recognize a pragma Inline that appears after the body
3674 Check_Inline_Pragma (Spec_Id);
3676 -- Deal with special case of a fully private operation in the body of
3677 -- the protected type. We must create a declaration for the subprogram,
3678 -- in order to attach the protected subprogram that will be used in
3679 -- internal calls. We exclude compiler generated bodies from the
3680 -- expander since the issue does not arise for those cases.
3683 and then Comes_From_Source (N)
3684 and then Is_Protected_Type (Current_Scope)
3686 Spec_Id := Build_Private_Protected_Declaration (N);
3689 -- If we are generating C and this is a function returning a constrained
3690 -- array type for which we must create a procedure with an extra out
3691 -- parameter, build and analyze the body now. The procedure declaration
3692 -- has already been created. We reuse the source body of the function,
3693 -- because in an instance it may contain global references that cannot
3694 -- be reanalyzed. The source function itself is not used any further,
3695 -- so we mark it as having a completion. If the subprogram is a stub the
3696 -- transformation is done later, when the proper body is analyzed.
3699 and then Modify_Tree_For_C
3700 and then Present (Spec_Id)
3701 and then Ekind (Spec_Id) = E_Function
3702 and then Nkind (N) /= N_Subprogram_Body_Stub
3703 and then Rewritten_For_C (Spec_Id)
3705 Set_Has_Completion (Spec_Id);
3707 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3710 -- The entity for the created procedure must remain invisible, so it
3711 -- does not participate in resolution of subsequent references to the
3714 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3718 -- If a separate spec is present, then deal with freezing issues
3720 if Present (Spec_Id) then
3721 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3722 Verify_Overriding_Indicator;
3724 -- In general, the spec will be frozen when we start analyzing the
3725 -- body. However, for internally generated operations, such as
3726 -- wrapper functions for inherited operations with controlling
3727 -- results, the spec may not have been frozen by the time we expand
3728 -- the freeze actions that include the bodies. In particular, extra
3729 -- formals for accessibility or for return-in-place may need to be
3730 -- generated. Freeze nodes, if any, are inserted before the current
3731 -- body. These freeze actions are also needed in ASIS mode and in
3732 -- Compile_Only mode to enable the proper back-end type annotations.
3733 -- They are necessary in any case to insure order of elaboration
3736 if not Is_Frozen (Spec_Id)
3737 and then (Expander_Active
3739 or else (Operating_Mode = Check_Semantics
3740 and then Serious_Errors_Detected = 0))
3742 -- The body generated for an expression function that is not a
3743 -- completion is a freeze point neither for the profile nor for
3744 -- anything else. That's why, in order to prevent any freezing
3745 -- during analysis, we need to mask types declared outside the
3746 -- expression that are not yet frozen.
3748 if Nkind (N) = N_Subprogram_Body
3749 and then Was_Expression_Function (N)
3750 and then not Has_Completion (Spec_Id)
3752 Set_Is_Frozen (Spec_Id);
3753 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3755 Set_Has_Delayed_Freeze (Spec_Id);
3756 Freeze_Before (N, Spec_Id);
3761 -- If the subprogram has a class-wide clone, build its body as a copy
3762 -- of the original body, and rewrite body of original subprogram as a
3763 -- wrapper that calls the clone.
3765 if Present (Spec_Id)
3766 and then Present (Class_Wide_Clone (Spec_Id))
3767 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3769 Build_Class_Wide_Clone_Body (Spec_Id, N);
3771 -- This is the new body for the existing primitive operation
3773 Rewrite (N, Build_Class_Wide_Clone_Call
3774 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3775 Set_Has_Completion (Spec_Id, False);
3780 -- Place subprogram on scope stack, and make formals visible. If there
3781 -- is a spec, the visible entity remains that of the spec.
3783 if Present (Spec_Id) then
3784 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3786 if Is_Child_Unit (Spec_Id) then
3787 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3791 Style.Check_Identifier (Body_Id, Spec_Id);
3794 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3795 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3797 if Is_Abstract_Subprogram (Spec_Id) then
3798 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3802 Set_Convention (Body_Id, Convention (Spec_Id));
3803 Set_Has_Completion (Spec_Id);
3805 if Is_Protected_Type (Scope (Spec_Id)) then
3806 Prot_Typ := Scope (Spec_Id);
3809 -- If this is a body generated for a renaming, do not check for
3810 -- full conformance. The check is redundant, because the spec of
3811 -- the body is a copy of the spec in the renaming declaration,
3812 -- and the test can lead to spurious errors on nested defaults.
3814 if Present (Spec_Decl)
3815 and then not Comes_From_Source (N)
3817 (Nkind (Original_Node (Spec_Decl)) =
3818 N_Subprogram_Renaming_Declaration
3819 or else (Present (Corresponding_Body (Spec_Decl))
3821 Nkind (Unit_Declaration_Node
3822 (Corresponding_Body (Spec_Decl))) =
3823 N_Subprogram_Renaming_Declaration))
3827 -- Conversely, the spec may have been generated for specless body
3828 -- with an inline pragma. The entity comes from source, which is
3829 -- both semantically correct and necessary for proper inlining.
3830 -- The subprogram declaration itself is not in the source.
3832 elsif Comes_From_Source (N)
3833 and then Present (Spec_Decl)
3834 and then not Comes_From_Source (Spec_Decl)
3835 and then Has_Pragma_Inline (Spec_Id)
3842 Fully_Conformant, True, Conformant, Body_Id);
3845 -- If the body is not fully conformant, we have to decide if we
3846 -- should analyze it or not. If it has a really messed up profile
3847 -- then we probably should not analyze it, since we will get too
3848 -- many bogus messages.
3850 -- Our decision is to go ahead in the non-fully conformant case
3851 -- only if it is at least mode conformant with the spec. Note
3852 -- that the call to Check_Fully_Conformant has issued the proper
3853 -- error messages to complain about the lack of conformance.
3856 and then not Mode_Conformant (Body_Id, Spec_Id)
3862 if Spec_Id /= Body_Id then
3863 Reference_Body_Formals (Spec_Id, Body_Id);
3866 Set_Ekind (Body_Id, E_Subprogram_Body);
3868 if Nkind (N) = N_Subprogram_Body_Stub then
3869 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3874 Set_Corresponding_Spec (N, Spec_Id);
3876 -- Ada 2005 (AI-345): If the operation is a primitive operation
3877 -- of a concurrent type, the type of the first parameter has been
3878 -- replaced with the corresponding record, which is the proper
3879 -- run-time structure to use. However, within the body there may
3880 -- be uses of the formals that depend on primitive operations
3881 -- of the type (in particular calls in prefixed form) for which
3882 -- we need the original concurrent type. The operation may have
3883 -- several controlling formals, so the replacement must be done
3886 if Comes_From_Source (Spec_Id)
3887 and then Present (First_Entity (Spec_Id))
3888 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3889 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3890 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3891 and then Present (Corresponding_Concurrent_Type
3892 (Etype (First_Entity (Spec_Id))))
3895 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3899 Form := First_Formal (Spec_Id);
3900 while Present (Form) loop
3901 if Etype (Form) = Typ then
3902 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3910 -- Make the formals visible, and place subprogram on scope stack.
3911 -- This is also the point at which we set Last_Real_Spec_Entity
3912 -- to mark the entities which will not be moved to the body.
3914 Install_Formals (Spec_Id);
3915 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3917 -- Within an instance, add local renaming declarations so that
3918 -- gdb can retrieve the values of actuals more easily. This is
3919 -- only relevant if generating code (and indeed we definitely
3920 -- do not want these definitions -gnatc mode, because that would
3923 if Is_Generic_Instance (Spec_Id)
3924 and then Is_Wrapper_Package (Current_Scope)
3925 and then Expander_Active
3927 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3930 Push_Scope (Spec_Id);
3932 -- Make sure that the subprogram is immediately visible. For
3933 -- child units that have no separate spec this is indispensable.
3934 -- Otherwise it is safe albeit redundant.
3936 Set_Is_Immediately_Visible (Spec_Id);
3939 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3940 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3941 Set_Scope (Body_Id, Scope (Spec_Id));
3943 -- Case of subprogram body with no previous spec
3946 -- Check for style warning required
3950 -- Only apply check for source level subprograms for which checks
3951 -- have not been suppressed.
3953 and then Comes_From_Source (Body_Id)
3954 and then not Suppress_Style_Checks (Body_Id)
3956 -- No warnings within an instance
3958 and then not In_Instance
3960 -- No warnings for expression functions
3962 and then Nkind (Original_Node (N)) /= N_Expression_Function
3964 Style.Body_With_No_Spec (N);
3967 New_Overloaded_Entity (Body_Id);
3969 if Nkind (N) /= N_Subprogram_Body_Stub then
3970 Set_Acts_As_Spec (N);
3971 Generate_Definition (Body_Id);
3973 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3975 -- If the body is an entry wrapper created for an entry with
3976 -- preconditions, it must be compiled in the context of the
3977 -- enclosing synchronized object, because it may mention other
3978 -- operations of the type.
3980 if Is_Entry_Wrapper (Body_Id) then
3982 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3985 Install_Declarations (Prot);
3989 Install_Formals (Body_Id);
3991 Push_Scope (Body_Id);
3994 -- For stubs and bodies with no previous spec, generate references to
3997 Generate_Reference_To_Formals (Body_Id);
4000 -- Entry barrier functions are generated outside the protected type and
4001 -- should not carry the SPARK_Mode of the enclosing context.
4003 if Nkind (N) = N_Subprogram_Body
4004 and then Is_Entry_Barrier_Function (N)
4008 -- The body is generated as part of expression function expansion. When
4009 -- the expression function appears in the visible declarations of a
4010 -- package, the body is added to the private declarations. Since both
4011 -- declarative lists may be subject to a different SPARK_Mode, inherit
4012 -- the mode of the spec.
4014 -- package P with SPARK_Mode is
4015 -- function Expr_Func ... is (...); -- original
4016 -- [function Expr_Func ...;] -- generated spec
4019 -- pragma SPARK_Mode (Off);
4020 -- [function Expr_Func ... is return ...;] -- generated body
4021 -- end P; -- mode is ON
4023 elsif not Comes_From_Source (N)
4024 and then Present (Spec_Id)
4025 and then Is_Expression_Function (Spec_Id)
4027 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4028 Set_SPARK_Pragma_Inherited
4029 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4031 -- Set the SPARK_Mode from the current context (may be overwritten later
4032 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4033 -- initially on a stand-alone subprogram body, but is then relocated to
4034 -- a generated corresponding spec. In this scenario the mode is shared
4035 -- between the spec and body.
4037 elsif No (SPARK_Pragma (Body_Id)) then
4038 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4039 Set_SPARK_Pragma_Inherited (Body_Id);
4042 -- A subprogram body may be instantiated or inlined at a later pass.
4043 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4044 -- applied to the initial declaration of the body.
4046 if Present (Spec_Id) then
4047 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4048 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4052 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4053 -- case the body is instantiated or inlined later and out of context.
4054 -- The body uses this attribute to restore the value of the global
4057 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4058 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4060 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4061 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4065 -- If this is the proper body of a stub, we must verify that the stub
4066 -- conforms to the body, and to the previous spec if one was present.
4067 -- We know already that the body conforms to that spec. This test is
4068 -- only required for subprograms that come from source.
4070 if Nkind (Parent (N)) = N_Subunit
4071 and then Comes_From_Source (N)
4072 and then not Error_Posted (Body_Id)
4073 and then Nkind (Corresponding_Stub (Parent (N))) =
4074 N_Subprogram_Body_Stub
4077 Old_Id : constant Entity_Id :=
4079 (Specification (Corresponding_Stub (Parent (N))));
4081 Conformant : Boolean := False;
4084 if No (Spec_Id) then
4085 Check_Fully_Conformant (Body_Id, Old_Id);
4089 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4091 if not Conformant then
4093 -- The stub was taken to be a new declaration. Indicate that
4096 Set_Has_Completion (Old_Id, False);
4102 Set_Has_Completion (Body_Id);
4103 Check_Eliminated (Body_Id);
4105 -- Analyze any aspect specifications that appear on the subprogram body
4106 -- stub. Stop the analysis now as the stub does not have a declarative
4107 -- or a statement part, and it cannot be inlined.
4109 if Nkind (N) = N_Subprogram_Body_Stub then
4110 if Has_Aspects (N) then
4111 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4119 -- Note: Normally we don't do any inlining if expansion is off, since
4120 -- we won't generate code in any case. An exception arises in GNATprove
4121 -- mode where we want to expand some calls in place, even with expansion
4122 -- disabled, since the inlining eases formal verification.
4124 if not GNATprove_Mode
4125 and then Expander_Active
4126 and then Serious_Errors_Detected = 0
4127 and then Present (Spec_Id)
4128 and then Has_Pragma_Inline (Spec_Id)
4130 -- Legacy implementation (relying on front-end inlining)
4132 if not Back_End_Inlining then
4133 if (Has_Pragma_Inline_Always (Spec_Id)
4134 and then not Opt.Disable_FE_Inline_Always)
4135 or else (Front_End_Inlining
4136 and then not Opt.Disable_FE_Inline)
4138 Build_Body_To_Inline (N, Spec_Id);
4141 -- New implementation (relying on back-end inlining)
4144 if Has_Pragma_Inline_Always (Spec_Id)
4145 or else Optimization_Level > 0
4147 -- Handle function returning an unconstrained type
4149 if Comes_From_Source (Body_Id)
4150 and then Ekind (Spec_Id) = E_Function
4151 and then Returns_Unconstrained_Type (Spec_Id)
4153 -- If function builds in place, i.e. returns a limited type,
4154 -- inlining cannot be done.
4156 and then not Is_Limited_Type (Etype (Spec_Id))
4158 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4162 Subp_Body : constant Node_Id :=
4163 Unit_Declaration_Node (Body_Id);
4164 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4167 -- Do not pass inlining to the backend if the subprogram
4168 -- has declarations or statements which cannot be inlined
4169 -- by the backend. This check is done here to emit an
4170 -- error instead of the generic warning message reported
4171 -- by the GCC backend (ie. "function might not be
4174 if Present (Subp_Decl)
4175 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4179 elsif Has_Excluded_Statement
4182 (Handled_Statement_Sequence (Subp_Body)))
4186 -- If the backend inlining is available then at this
4187 -- stage we only have to mark the subprogram as inlined.
4188 -- The expander will take care of registering it in the
4189 -- table of subprograms inlined by the backend a part of
4190 -- processing calls to it (cf. Expand_Call)
4193 Set_Is_Inlined (Spec_Id);
4200 -- In GNATprove mode, inline only when there is a separate subprogram
4201 -- declaration for now, as inlining of subprogram bodies acting as
4202 -- declarations, or subprogram stubs, are not supported by front-end
4203 -- inlining. This inlining should occur after analysis of the body, so
4204 -- that it is known whether the value of SPARK_Mode, which can be
4205 -- defined by a pragma inside the body, is applicable to the body.
4206 -- Inlining can be disabled with switch -gnatdm
4208 elsif GNATprove_Mode
4209 and then Full_Analysis
4210 and then not Inside_A_Generic
4211 and then Present (Spec_Id)
4213 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4214 and then Body_Has_SPARK_Mode_On
4215 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4216 and then not Body_Has_Contract
4217 and then not Debug_Flag_M
4219 Build_Body_To_Inline (N, Spec_Id);
4222 -- When generating code, inherited pre/postconditions are handled when
4223 -- expanding the corresponding contract.
4225 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4226 -- of the specification we have to install the private withed units.
4227 -- This holds for child units as well.
4229 if Is_Compilation_Unit (Body_Id)
4230 or else Nkind (Parent (N)) = N_Compilation_Unit
4232 Install_Private_With_Clauses (Body_Id);
4235 Check_Anonymous_Return;
4237 -- Set the Protected_Formal field of each extra formal of the protected
4238 -- subprogram to reference the corresponding extra formal of the
4239 -- subprogram that implements it. For regular formals this occurs when
4240 -- the protected subprogram's declaration is expanded, but the extra
4241 -- formals don't get created until the subprogram is frozen. We need to
4242 -- do this before analyzing the protected subprogram's body so that any
4243 -- references to the original subprogram's extra formals will be changed
4244 -- refer to the implementing subprogram's formals (see Expand_Formal).
4246 if Present (Spec_Id)
4247 and then Is_Protected_Type (Scope (Spec_Id))
4248 and then Present (Protected_Body_Subprogram (Spec_Id))
4251 Impl_Subp : constant Entity_Id :=
4252 Protected_Body_Subprogram (Spec_Id);
4253 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4254 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4257 while Present (Prot_Ext_Formal) loop
4258 pragma Assert (Present (Impl_Ext_Formal));
4259 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4260 Next_Formal_With_Extras (Prot_Ext_Formal);
4261 Next_Formal_With_Extras (Impl_Ext_Formal);
4266 -- Now we can go on to analyze the body
4268 HSS := Handled_Statement_Sequence (N);
4269 Set_Actual_Subtypes (N, Current_Scope);
4271 -- Add a declaration for the Protection object, renaming declarations
4272 -- for discriminals and privals and finally a declaration for the entry
4273 -- family index (if applicable). This form of early expansion is done
4274 -- when the Expander is active because Install_Private_Data_Declarations
4275 -- references entities which were created during regular expansion. The
4276 -- subprogram entity must come from source, and not be an internally
4277 -- generated subprogram.
4280 and then Present (Prot_Typ)
4281 and then Present (Spec_Id)
4282 and then Comes_From_Source (Spec_Id)
4283 and then not Is_Eliminated (Spec_Id)
4285 Install_Private_Data_Declarations
4286 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4289 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4290 -- may now appear in parameter and result profiles. Since the analysis
4291 -- of a subprogram body may use the parameter and result profile of the
4292 -- spec, swap any limited views with their non-limited counterpart.
4294 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4295 Exch_Views := Exchange_Limited_Views (Spec_Id);
4298 -- If the return type is an anonymous access type whose designated type
4299 -- is the limited view of a class-wide type and the non-limited view is
4300 -- available, update the return type accordingly.
4302 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4308 Rtyp := Etype (Spec_Id);
4310 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4311 Etyp := Directly_Designated_Type (Rtyp);
4313 if Is_Class_Wide_Type (Etyp)
4314 and then From_Limited_With (Etyp)
4317 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4323 -- Analyze any aspect specifications that appear on the subprogram body
4325 if Has_Aspects (N) then
4326 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4329 Analyze_Declarations (Declarations (N));
4331 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4333 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4334 if Present (SPARK_Pragma (Spec_Id)) then
4335 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4337 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4339 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4340 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4341 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4343 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4346 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4350 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4351 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4352 Error_Msg_Sloc := Sloc (Spec_Id);
4354 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4358 -- A subprogram body "freezes" its own contract. Analyze the contract
4359 -- after the declarations of the body have been processed as pragmas
4360 -- are now chained on the contract of the subprogram body.
4362 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4364 -- Check completion, and analyze the statements
4367 Inspect_Deferred_Constant_Completion (Declarations (N));
4370 -- Deal with end of scope processing for the body
4372 Process_End_Label (HSS, 't', Current_Scope);
4373 Update_Use_Clause_Chain;
4376 -- If we are compiling an entry wrapper, remove the enclosing
4377 -- synchronized object from the stack.
4379 if Is_Entry_Wrapper (Body_Id) then
4383 Check_Subprogram_Order (N);
4384 Set_Analyzed (Body_Id);
4386 -- If we have a separate spec, then the analysis of the declarations
4387 -- caused the entities in the body to be chained to the spec id, but
4388 -- we want them chained to the body id. Only the formal parameters
4389 -- end up chained to the spec id in this case.
4391 if Present (Spec_Id) then
4393 -- We must conform to the categorization of our spec
4395 Validate_Categorization_Dependency (N, Spec_Id);
4397 -- And if this is a child unit, the parent units must conform
4399 if Is_Child_Unit (Spec_Id) then
4400 Validate_Categorization_Dependency
4401 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4404 -- Here is where we move entities from the spec to the body
4406 -- Case where there are entities that stay with the spec
4408 if Present (Last_Real_Spec_Entity) then
4410 -- No body entities (happens when the only real spec entities come
4411 -- from precondition and postcondition pragmas).
4413 if No (Last_Entity (Body_Id)) then
4414 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4416 -- Body entities present (formals), so chain stuff past them
4420 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4423 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4424 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4425 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4427 -- Case where there are no spec entities, in this case there can be
4428 -- no body entities either, so just move everything.
4430 -- If the body is generated for an expression function, it may have
4431 -- been preanalyzed already, if 'access was applied to it.
4434 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4435 N_Expression_Function
4437 pragma Assert (No (Last_Entity (Body_Id)));
4441 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4442 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4443 Set_First_Entity (Spec_Id, Empty);
4444 Set_Last_Entity (Spec_Id, Empty);
4448 Check_Missing_Return;
4450 -- Now we are going to check for variables that are never modified in
4451 -- the body of the procedure. But first we deal with a special case
4452 -- where we want to modify this check. If the body of the subprogram
4453 -- starts with a raise statement or its equivalent, or if the body
4454 -- consists entirely of a null statement, then it is pretty obvious that
4455 -- it is OK to not reference the parameters. For example, this might be
4456 -- the following common idiom for a stubbed function: statement of the
4457 -- procedure raises an exception. In particular this deals with the
4458 -- common idiom of a stubbed function, which appears something like:
4460 -- function F (A : Integer) return Some_Type;
4463 -- raise Program_Error;
4467 -- Here the purpose of X is simply to satisfy the annoying requirement
4468 -- in Ada that there be at least one return, and we certainly do not
4469 -- want to go posting warnings on X that it is not initialized. On
4470 -- the other hand, if X is entirely unreferenced that should still
4473 -- What we do is to detect these cases, and if we find them, flag the
4474 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4475 -- suppress unwanted warnings. For the case of the function stub above
4476 -- we have a special test to set X as apparently assigned to suppress
4483 -- Skip call markers installed by the ABE mechanism, labels, and
4484 -- Push_xxx_Error_Label to find the first real statement.
4486 Stm := First (Statements (HSS));
4487 while Nkind_In (Stm, N_Call_Marker, N_Label)
4488 or else Nkind (Stm) in N_Push_xxx_Label
4493 -- Do the test on the original statement before expansion
4496 Ostm : constant Node_Id := Original_Node (Stm);
4499 -- If explicit raise statement, turn on flag
4501 if Nkind (Ostm) = N_Raise_Statement then
4502 Set_Trivial_Subprogram (Stm);
4504 -- If null statement, and no following statements, turn on flag
4506 elsif Nkind (Stm) = N_Null_Statement
4507 and then Comes_From_Source (Stm)
4508 and then No (Next (Stm))
4510 Set_Trivial_Subprogram (Stm);
4512 -- Check for explicit call cases which likely raise an exception
4514 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4515 if Is_Entity_Name (Name (Ostm)) then
4517 Ent : constant Entity_Id := Entity (Name (Ostm));
4520 -- If the procedure is marked No_Return, then likely it
4521 -- raises an exception, but in any case it is not coming
4522 -- back here, so turn on the flag.
4525 and then Ekind (Ent) = E_Procedure
4526 and then No_Return (Ent)
4528 Set_Trivial_Subprogram (Stm);
4536 -- Check for variables that are never modified
4543 -- If there is a separate spec, then transfer Never_Set_In_Source
4544 -- flags from out parameters to the corresponding entities in the
4545 -- body. The reason we do that is we want to post error flags on
4546 -- the body entities, not the spec entities.
4548 if Present (Spec_Id) then
4549 E1 := First_Entity (Spec_Id);
4550 while Present (E1) loop
4551 if Ekind (E1) = E_Out_Parameter then
4552 E2 := First_Entity (Body_Id);
4553 while Present (E2) loop
4554 exit when Chars (E1) = Chars (E2);
4558 if Present (E2) then
4559 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4567 -- Check references in body
4569 Check_References (Body_Id);
4572 -- Check for nested subprogram, and mark outer level subprogram if so
4578 if Present (Spec_Id) then
4585 Ent := Enclosing_Subprogram (Ent);
4586 exit when No (Ent) or else Is_Subprogram (Ent);
4589 if Present (Ent) then
4590 Set_Has_Nested_Subprogram (Ent);
4594 -- Restore the limited views in the spec, if any, to let the back end
4595 -- process it without running into circularities.
4597 if Exch_Views /= No_Elist then
4598 Restore_Limited_Views (Exch_Views);
4601 if Mask_Types /= No_Elist then
4602 Unmask_Unfrozen_Types (Mask_Types);
4605 if Present (Desig_View) then
4606 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4610 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4611 Restore_Ghost_Mode (Saved_GM);
4612 end Analyze_Subprogram_Body_Helper;
4614 ------------------------------------
4615 -- Analyze_Subprogram_Declaration --
4616 ------------------------------------
4618 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4619 Scop : constant Entity_Id := Current_Scope;
4620 Designator : Entity_Id;
4622 Is_Completion : Boolean;
4623 -- Indicates whether a null procedure declaration is a completion
4626 -- Null procedures are not allowed in SPARK
4628 if Nkind (Specification (N)) = N_Procedure_Specification
4629 and then Null_Present (Specification (N))
4631 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4633 -- Null procedures are allowed in protected types, following the
4634 -- recent AI12-0147.
4636 if Is_Protected_Type (Current_Scope)
4637 and then Ada_Version < Ada_2012
4639 Error_Msg_N ("protected operation cannot be a null procedure", N);
4642 Analyze_Null_Procedure (N, Is_Completion);
4644 -- The null procedure acts as a body, nothing further is needed
4646 if Is_Completion then
4651 Designator := Analyze_Subprogram_Specification (Specification (N));
4653 -- A reference may already have been generated for the unit name, in
4654 -- which case the following call is redundant. However it is needed for
4655 -- declarations that are the rewriting of an expression function.
4657 Generate_Definition (Designator);
4659 -- Set the SPARK mode from the current context (may be overwritten later
4660 -- with explicit pragma). This is not done for entry barrier functions
4661 -- because they are generated outside the protected type and should not
4662 -- carry the mode of the enclosing context.
4664 if Nkind (N) = N_Subprogram_Declaration
4665 and then Is_Entry_Barrier_Function (N)
4670 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4671 Set_SPARK_Pragma_Inherited (Designator);
4674 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4675 -- the body of this subprogram is instantiated or inlined later and out
4676 -- of context. The body uses this attribute to restore the value of the
4679 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4680 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4683 -- Preserve relevant elaboration-related attributes of the context which
4684 -- are no longer available or very expensive to recompute once analysis,
4685 -- resolution, and expansion are over.
4687 Mark_Elaboration_Attributes
4688 (N_Id => Designator,
4691 if Debug_Flag_C then
4692 Write_Str ("==> subprogram spec ");
4693 Write_Name (Chars (Designator));
4694 Write_Str (" from ");
4695 Write_Location (Sloc (N));
4700 Validate_RCI_Subprogram_Declaration (N);
4701 New_Overloaded_Entity (Designator);
4702 Check_Delayed_Subprogram (Designator);
4704 -- If the type of the first formal of the current subprogram is a non-
4705 -- generic tagged private type, mark the subprogram as being a private
4706 -- primitive. Ditto if this is a function with controlling result, and
4707 -- the return type is currently private. In both cases, the type of the
4708 -- controlling argument or result must be in the current scope for the
4709 -- operation to be primitive.
4711 if Has_Controlling_Result (Designator)
4712 and then Is_Private_Type (Etype (Designator))
4713 and then Scope (Etype (Designator)) = Current_Scope
4714 and then not Is_Generic_Actual_Type (Etype (Designator))
4716 Set_Is_Private_Primitive (Designator);
4718 elsif Present (First_Formal (Designator)) then
4720 Formal_Typ : constant Entity_Id :=
4721 Etype (First_Formal (Designator));
4723 Set_Is_Private_Primitive (Designator,
4724 Is_Tagged_Type (Formal_Typ)
4725 and then Scope (Formal_Typ) = Current_Scope
4726 and then Is_Private_Type (Formal_Typ)
4727 and then not Is_Generic_Actual_Type (Formal_Typ));
4731 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4734 if Ada_Version >= Ada_2005
4735 and then Comes_From_Source (N)
4736 and then Is_Dispatching_Operation (Designator)
4743 if Has_Controlling_Result (Designator) then
4744 Etyp := Etype (Designator);
4747 E := First_Entity (Designator);
4749 and then Is_Formal (E)
4750 and then not Is_Controlling_Formal (E)
4758 if Is_Access_Type (Etyp) then
4759 Etyp := Directly_Designated_Type (Etyp);
4762 if Is_Interface (Etyp)
4763 and then not Is_Abstract_Subprogram (Designator)
4764 and then not (Ekind (Designator) = E_Procedure
4765 and then Null_Present (Specification (N)))
4767 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4769 -- Specialize error message based on procedures vs. functions,
4770 -- since functions can't be null subprograms.
4772 if Ekind (Designator) = E_Procedure then
4774 ("interface procedure % must be abstract or null", N);
4777 ("interface function % must be abstract", N);
4783 -- What is the following code for, it used to be
4785 -- ??? Set_Suppress_Elaboration_Checks
4786 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4788 -- The following seems equivalent, but a bit dubious
4790 if Elaboration_Checks_Suppressed (Designator) then
4791 Set_Kill_Elaboration_Checks (Designator);
4794 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4795 Set_Categorization_From_Scope (Designator, Scop);
4798 -- For a compilation unit, check for library-unit pragmas
4800 Push_Scope (Designator);
4801 Set_Categorization_From_Pragmas (N);
4802 Validate_Categorization_Dependency (N, Designator);
4806 -- For a compilation unit, set body required. This flag will only be
4807 -- reset if a valid Import or Interface pragma is processed later on.
4809 if Nkind (Parent (N)) = N_Compilation_Unit then
4810 Set_Body_Required (Parent (N), True);
4812 if Ada_Version >= Ada_2005
4813 and then Nkind (Specification (N)) = N_Procedure_Specification
4814 and then Null_Present (Specification (N))
4817 ("null procedure cannot be declared at library level", N);
4821 Generate_Reference_To_Formals (Designator);
4822 Check_Eliminated (Designator);
4824 if Debug_Flag_C then
4826 Write_Str ("<== subprogram spec ");
4827 Write_Name (Chars (Designator));
4828 Write_Str (" from ");
4829 Write_Location (Sloc (N));
4833 if Is_Protected_Type (Current_Scope) then
4835 -- Indicate that this is a protected operation, because it may be
4836 -- used in subsequent declarations within the protected type.
4838 Set_Convention (Designator, Convention_Protected);
4841 List_Inherited_Pre_Post_Aspects (Designator);
4843 if Has_Aspects (N) then
4844 Analyze_Aspect_Specifications (N, Designator);
4846 end Analyze_Subprogram_Declaration;
4848 --------------------------------------
4849 -- Analyze_Subprogram_Specification --
4850 --------------------------------------
4852 -- Reminder: N here really is a subprogram specification (not a subprogram
4853 -- declaration). This procedure is called to analyze the specification in
4854 -- both subprogram bodies and subprogram declarations (specs).
4856 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4857 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4858 -- Determine whether entity E denotes the spec or body of an invariant
4861 ------------------------------------
4862 -- Is_Invariant_Procedure_Or_Body --
4863 ------------------------------------
4865 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4866 Decl : constant Node_Id := Unit_Declaration_Node (E);
4870 if Nkind (Decl) = N_Subprogram_Body then
4871 Spec := Corresponding_Spec (Decl);
4878 and then Ekind (Spec) = E_Procedure
4879 and then (Is_Partial_Invariant_Procedure (Spec)
4880 or else Is_Invariant_Procedure (Spec));
4881 end Is_Invariant_Procedure_Or_Body;
4885 Designator : constant Entity_Id := Defining_Entity (N);
4886 Formals : constant List_Id := Parameter_Specifications (N);
4888 -- Start of processing for Analyze_Subprogram_Specification
4891 -- User-defined operator is not allowed in SPARK, except as a renaming
4893 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4894 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4896 Check_SPARK_05_Restriction
4897 ("user-defined operator is not allowed", N);
4900 -- Proceed with analysis. Do not emit a cross-reference entry if the
4901 -- specification comes from an expression function, because it may be
4902 -- the completion of a previous declaration. It is not, the cross-
4903 -- reference entry will be emitted for the new subprogram declaration.
4905 if Nkind (Parent (N)) /= N_Expression_Function then
4906 Generate_Definition (Designator);
4909 if Nkind (N) = N_Function_Specification then
4910 Set_Ekind (Designator, E_Function);
4911 Set_Mechanism (Designator, Default_Mechanism);
4913 Set_Ekind (Designator, E_Procedure);
4914 Set_Etype (Designator, Standard_Void_Type);
4917 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4918 -- those subprograms which could be inlined in GNATprove mode (because
4919 -- Body_To_Inline is non-Empty) but should not be inlined.
4921 if GNATprove_Mode then
4922 Set_Is_Inlined_Always (Designator);
4925 -- Introduce new scope for analysis of the formals and the return type
4927 Set_Scope (Designator, Current_Scope);
4929 if Present (Formals) then
4930 Push_Scope (Designator);
4931 Process_Formals (Formals, N);
4933 -- Check dimensions in N for formals with default expression
4935 Analyze_Dimension_Formals (N, Formals);
4937 -- Ada 2005 (AI-345): If this is an overriding operation of an
4938 -- inherited interface operation, and the controlling type is
4939 -- a synchronized type, replace the type with its corresponding
4940 -- record, to match the proper signature of an overriding operation.
4941 -- Same processing for an access parameter whose designated type is
4942 -- derived from a synchronized interface.
4944 -- This modification is not done for invariant procedures because
4945 -- the corresponding record may not necessarely be visible when the
4946 -- concurrent type acts as the full view of a private type.
4949 -- type Prot is private with Type_Invariant => ...;
4950 -- procedure ConcInvariant (Obj : Prot);
4952 -- protected type Prot is ...;
4953 -- type Concurrent_Record_Prot is record ...;
4954 -- procedure ConcInvariant (Obj : Prot) is
4956 -- end ConcInvariant;
4959 -- In the example above, both the spec and body of the invariant
4960 -- procedure must utilize the private type as the controlling type.
4962 if Ada_Version >= Ada_2005
4963 and then not Is_Invariant_Procedure_Or_Body (Designator)
4967 Formal_Typ : Entity_Id;
4968 Rec_Typ : Entity_Id;
4969 Desig_Typ : Entity_Id;
4972 Formal := First_Formal (Designator);
4973 while Present (Formal) loop
4974 Formal_Typ := Etype (Formal);
4976 if Is_Concurrent_Type (Formal_Typ)
4977 and then Present (Corresponding_Record_Type (Formal_Typ))
4979 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4981 if Present (Interfaces (Rec_Typ)) then
4982 Set_Etype (Formal, Rec_Typ);
4985 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4986 Desig_Typ := Designated_Type (Formal_Typ);
4988 if Is_Concurrent_Type (Desig_Typ)
4989 and then Present (Corresponding_Record_Type (Desig_Typ))
4991 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4993 if Present (Interfaces (Rec_Typ)) then
4994 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
4999 Next_Formal (Formal);
5006 -- The subprogram scope is pushed and popped around the processing of
5007 -- the return type for consistency with call above to Process_Formals
5008 -- (which itself can call Analyze_Return_Type), and to ensure that any
5009 -- itype created for the return type will be associated with the proper
5012 elsif Nkind (N) = N_Function_Specification then
5013 Push_Scope (Designator);
5014 Analyze_Return_Type (N);
5020 if Nkind (N) = N_Function_Specification then
5022 -- Deal with operator symbol case
5024 if Nkind (Designator) = N_Defining_Operator_Symbol then
5025 Valid_Operator_Definition (Designator);
5028 May_Need_Actuals (Designator);
5030 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5031 -- the subprogram is abstract also. This does not apply to renaming
5032 -- declarations, where abstractness is inherited, and to subprogram
5033 -- bodies generated for stream operations, which become renamings as
5036 -- In case of primitives associated with abstract interface types
5037 -- the check is applied later (see Analyze_Subprogram_Declaration).
5039 if not Nkind_In (Original_Node (Parent (N)),
5040 N_Abstract_Subprogram_Declaration,
5041 N_Formal_Abstract_Subprogram_Declaration,
5042 N_Subprogram_Renaming_Declaration)
5044 if Is_Abstract_Type (Etype (Designator))
5045 and then not Is_Interface (Etype (Designator))
5048 ("function that returns abstract type must be abstract", N);
5050 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5051 -- access result whose designated type is abstract.
5053 elsif Ada_Version >= Ada_2012
5054 and then Nkind (Result_Definition (N)) = N_Access_Definition
5056 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5057 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5060 ("function whose access result designates abstract type "
5061 & "must be abstract", N);
5067 end Analyze_Subprogram_Specification;
5069 -----------------------
5070 -- Check_Conformance --
5071 -----------------------
5073 procedure Check_Conformance
5074 (New_Id : Entity_Id;
5076 Ctype : Conformance_Type;
5078 Conforms : out Boolean;
5079 Err_Loc : Node_Id := Empty;
5080 Get_Inst : Boolean := False;
5081 Skip_Controlling_Formals : Boolean := False)
5083 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5084 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5085 -- If Errmsg is True, then processing continues to post an error message
5086 -- for conformance error on given node. Two messages are output. The
5087 -- first message points to the previous declaration with a general "no
5088 -- conformance" message. The second is the detailed reason, supplied as
5089 -- Msg. The parameter N provide information for a possible & insertion
5090 -- in the message, and also provides the location for posting the
5091 -- message in the absence of a specified Err_Loc location.
5093 function Conventions_Match
5095 Id2 : Entity_Id) return Boolean;
5096 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5099 -----------------------
5100 -- Conformance_Error --
5101 -----------------------
5103 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5110 if No (Err_Loc) then
5116 Error_Msg_Sloc := Sloc (Old_Id);
5119 when Type_Conformant =>
5120 Error_Msg_N -- CODEFIX
5121 ("not type conformant with declaration#!", Enode);
5123 when Mode_Conformant =>
5124 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5126 ("not mode conformant with operation inherited#!",
5130 ("not mode conformant with declaration#!", Enode);
5133 when Subtype_Conformant =>
5134 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5136 ("not subtype conformant with operation inherited#!",
5140 ("not subtype conformant with declaration#!", Enode);
5143 when Fully_Conformant =>
5144 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5145 Error_Msg_N -- CODEFIX
5146 ("not fully conformant with operation inherited#!",
5149 Error_Msg_N -- CODEFIX
5150 ("not fully conformant with declaration#!", Enode);
5154 Error_Msg_NE (Msg, Enode, N);
5156 end Conformance_Error;
5158 -----------------------
5159 -- Conventions_Match --
5160 -----------------------
5162 function Conventions_Match
5164 Id2 : Entity_Id) return Boolean
5167 -- Ignore the conventions of anonymous access-to-subprogram types
5168 -- and subprogram types because these are internally generated and
5169 -- the only way these may receive a convention is if they inherit
5170 -- the convention of a related subprogram.
5172 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5175 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5180 -- Otherwise compare the conventions directly
5183 return Convention (Id1) = Convention (Id2);
5185 end Conventions_Match;
5189 Old_Type : constant Entity_Id := Etype (Old_Id);
5190 New_Type : constant Entity_Id := Etype (New_Id);
5191 Old_Formal : Entity_Id;
5192 New_Formal : Entity_Id;
5193 Access_Types_Match : Boolean;
5194 Old_Formal_Base : Entity_Id;
5195 New_Formal_Base : Entity_Id;
5197 -- Start of processing for Check_Conformance
5202 -- We need a special case for operators, since they don't appear
5205 if Ctype = Type_Conformant then
5206 if Ekind (New_Id) = E_Operator
5207 and then Operator_Matches_Spec (New_Id, Old_Id)
5213 -- If both are functions/operators, check return types conform
5215 if Old_Type /= Standard_Void_Type
5217 New_Type /= Standard_Void_Type
5219 -- If we are checking interface conformance we omit controlling
5220 -- arguments and result, because we are only checking the conformance
5221 -- of the remaining parameters.
5223 if Has_Controlling_Result (Old_Id)
5224 and then Has_Controlling_Result (New_Id)
5225 and then Skip_Controlling_Formals
5229 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5230 if Ctype >= Subtype_Conformant
5231 and then not Predicates_Match (Old_Type, New_Type)
5234 ("\predicate of return type does not match!", New_Id);
5237 ("\return type does not match!", New_Id);
5243 -- Ada 2005 (AI-231): In case of anonymous access types check the
5244 -- null-exclusion and access-to-constant attributes match.
5246 if Ada_Version >= Ada_2005
5247 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5249 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5250 or else Is_Access_Constant (Etype (Old_Type)) /=
5251 Is_Access_Constant (Etype (New_Type)))
5253 Conformance_Error ("\return type does not match!", New_Id);
5257 -- If either is a function/operator and the other isn't, error
5259 elsif Old_Type /= Standard_Void_Type
5260 or else New_Type /= Standard_Void_Type
5262 Conformance_Error ("\functions can only match functions!", New_Id);
5266 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5267 -- If this is a renaming as body, refine error message to indicate that
5268 -- the conflict is with the original declaration. If the entity is not
5269 -- frozen, the conventions don't have to match, the one of the renamed
5270 -- entity is inherited.
5272 if Ctype >= Subtype_Conformant then
5273 if not Conventions_Match (Old_Id, New_Id) then
5274 if not Is_Frozen (New_Id) then
5277 elsif Present (Err_Loc)
5278 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5279 and then Present (Corresponding_Spec (Err_Loc))
5281 Error_Msg_Name_1 := Chars (New_Id);
5283 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5284 Conformance_Error ("\prior declaration for% has convention %!");
5287 Conformance_Error ("\calling conventions do not match!");
5292 elsif Is_Formal_Subprogram (Old_Id)
5293 or else Is_Formal_Subprogram (New_Id)
5295 Conformance_Error ("\formal subprograms not allowed!");
5300 -- Deal with parameters
5302 -- Note: we use the entity information, rather than going directly
5303 -- to the specification in the tree. This is not only simpler, but
5304 -- absolutely necessary for some cases of conformance tests between
5305 -- operators, where the declaration tree simply does not exist.
5307 Old_Formal := First_Formal (Old_Id);
5308 New_Formal := First_Formal (New_Id);
5309 while Present (Old_Formal) and then Present (New_Formal) loop
5310 if Is_Controlling_Formal (Old_Formal)
5311 and then Is_Controlling_Formal (New_Formal)
5312 and then Skip_Controlling_Formals
5314 -- The controlling formals will have different types when
5315 -- comparing an interface operation with its match, but both
5316 -- or neither must be access parameters.
5318 if Is_Access_Type (Etype (Old_Formal))
5320 Is_Access_Type (Etype (New_Formal))
5322 goto Skip_Controlling_Formal;
5325 ("\access parameter does not match!", New_Formal);
5329 -- Ada 2012: Mode conformance also requires that formal parameters
5330 -- be both aliased, or neither.
5332 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5333 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5335 ("\aliased parameter mismatch!", New_Formal);
5339 if Ctype = Fully_Conformant then
5341 -- Names must match. Error message is more accurate if we do
5342 -- this before checking that the types of the formals match.
5344 if Chars (Old_Formal) /= Chars (New_Formal) then
5345 Conformance_Error ("\name& does not match!", New_Formal);
5347 -- Set error posted flag on new formal as well to stop
5348 -- junk cascaded messages in some cases.
5350 Set_Error_Posted (New_Formal);
5354 -- Null exclusion must match
5356 if Null_Exclusion_Present (Parent (Old_Formal))
5358 Null_Exclusion_Present (Parent (New_Formal))
5360 -- Only give error if both come from source. This should be
5361 -- investigated some time, since it should not be needed ???
5363 if Comes_From_Source (Old_Formal)
5365 Comes_From_Source (New_Formal)
5368 ("\null exclusion for& does not match", New_Formal);
5370 -- Mark error posted on the new formal to avoid duplicated
5371 -- complaint about types not matching.
5373 Set_Error_Posted (New_Formal);
5378 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5379 -- case occurs whenever a subprogram is being renamed and one of its
5380 -- parameters imposes a null exclusion. For example:
5382 -- type T is null record;
5383 -- type Acc_T is access T;
5384 -- subtype Acc_T_Sub is Acc_T;
5386 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5387 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5390 Old_Formal_Base := Etype (Old_Formal);
5391 New_Formal_Base := Etype (New_Formal);
5394 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5395 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5398 Access_Types_Match := Ada_Version >= Ada_2005
5400 -- Ensure that this rule is only applied when New_Id is a
5401 -- renaming of Old_Id.
5403 and then Nkind (Parent (Parent (New_Id))) =
5404 N_Subprogram_Renaming_Declaration
5405 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5406 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5407 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5409 -- Now handle the allowed access-type case
5411 and then Is_Access_Type (Old_Formal_Base)
5412 and then Is_Access_Type (New_Formal_Base)
5414 -- The type kinds must match. The only exception occurs with
5415 -- multiple generics of the form:
5418 -- type F is private; type A is private;
5419 -- type F_Ptr is access F; type A_Ptr is access A;
5420 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5421 -- package F_Pack is ... package A_Pack is
5422 -- package F_Inst is
5423 -- new F_Pack (A, A_Ptr, A_P);
5425 -- When checking for conformance between the parameters of A_P
5426 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5427 -- because the compiler has transformed A_Ptr into a subtype of
5428 -- F_Ptr. We catch this case in the code below.
5430 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5432 (Is_Generic_Type (Old_Formal_Base)
5433 and then Is_Generic_Type (New_Formal_Base)
5434 and then Is_Internal (New_Formal_Base)
5435 and then Etype (Etype (New_Formal_Base)) =
5437 and then Directly_Designated_Type (Old_Formal_Base) =
5438 Directly_Designated_Type (New_Formal_Base)
5439 and then ((Is_Itype (Old_Formal_Base)
5440 and then Can_Never_Be_Null (Old_Formal_Base))
5442 (Is_Itype (New_Formal_Base)
5443 and then Can_Never_Be_Null (New_Formal_Base)));
5445 -- Types must always match. In the visible part of an instance,
5446 -- usual overloading rules for dispatching operations apply, and
5447 -- we check base types (not the actual subtypes).
5449 if In_Instance_Visible_Part
5450 and then Is_Dispatching_Operation (New_Id)
5452 if not Conforming_Types
5453 (T1 => Base_Type (Etype (Old_Formal)),
5454 T2 => Base_Type (Etype (New_Formal)),
5456 Get_Inst => Get_Inst)
5457 and then not Access_Types_Match
5459 Conformance_Error ("\type of & does not match!", New_Formal);
5463 elsif not Conforming_Types
5464 (T1 => Old_Formal_Base,
5465 T2 => New_Formal_Base,
5467 Get_Inst => Get_Inst)
5468 and then not Access_Types_Match
5470 -- Don't give error message if old type is Any_Type. This test
5471 -- avoids some cascaded errors, e.g. in case of a bad spec.
5473 if Errmsg and then Old_Formal_Base = Any_Type then
5476 if Ctype >= Subtype_Conformant
5478 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5481 ("\predicate of & does not match!", New_Formal);
5484 ("\type of & does not match!", New_Formal);
5486 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5488 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5496 -- For mode conformance, mode must match
5498 if Ctype >= Mode_Conformant then
5499 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5500 if not Ekind_In (New_Id, E_Function, E_Procedure)
5501 or else not Is_Primitive_Wrapper (New_Id)
5503 Conformance_Error ("\mode of & does not match!", New_Formal);
5507 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5509 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5511 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5514 ("\mode of & does not match!", New_Formal);
5521 -- Part of mode conformance for access types is having the same
5522 -- constant modifier.
5524 elsif Access_Types_Match
5525 and then Is_Access_Constant (Old_Formal_Base) /=
5526 Is_Access_Constant (New_Formal_Base)
5529 ("\constant modifier does not match!", New_Formal);
5534 if Ctype >= Subtype_Conformant then
5536 -- Ada 2005 (AI-231): In case of anonymous access types check
5537 -- the null-exclusion and access-to-constant attributes must
5538 -- match. For null exclusion, we test the types rather than the
5539 -- formals themselves, since the attribute is only set reliably
5540 -- on the formals in the Ada 95 case, and we exclude the case
5541 -- where Old_Formal is marked as controlling, to avoid errors
5542 -- when matching completing bodies with dispatching declarations
5543 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5545 if Ada_Version >= Ada_2005
5546 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5547 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5549 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5550 Can_Never_Be_Null (Etype (New_Formal))
5552 not Is_Controlling_Formal (Old_Formal))
5554 Is_Access_Constant (Etype (Old_Formal)) /=
5555 Is_Access_Constant (Etype (New_Formal)))
5557 -- Do not complain if error already posted on New_Formal. This
5558 -- avoids some redundant error messages.
5560 and then not Error_Posted (New_Formal)
5562 -- It is allowed to omit the null-exclusion in case of stream
5563 -- attribute subprograms. We recognize stream subprograms
5564 -- through their TSS-generated suffix.
5567 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5570 if TSS_Name /= TSS_Stream_Read
5571 and then TSS_Name /= TSS_Stream_Write
5572 and then TSS_Name /= TSS_Stream_Input
5573 and then TSS_Name /= TSS_Stream_Output
5575 -- Here we have a definite conformance error. It is worth
5576 -- special casing the error message for the case of a
5577 -- controlling formal (which excludes null).
5579 if Is_Controlling_Formal (New_Formal) then
5580 Error_Msg_Node_2 := Scope (New_Formal);
5582 ("\controlling formal & of & excludes null, "
5583 & "declaration must exclude null as well",
5586 -- Normal case (couldn't we give more detail here???)
5590 ("\type of & does not match!", New_Formal);
5599 -- Full conformance checks
5601 if Ctype = Fully_Conformant then
5603 -- We have checked already that names match
5605 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5607 -- Check default expressions for in parameters
5610 NewD : constant Boolean :=
5611 Present (Default_Value (New_Formal));
5612 OldD : constant Boolean :=
5613 Present (Default_Value (Old_Formal));
5615 if NewD or OldD then
5617 -- The old default value has been analyzed because the
5618 -- current full declaration will have frozen everything
5619 -- before. The new default value has not been analyzed,
5620 -- so analyze it now before we check for conformance.
5623 Push_Scope (New_Id);
5624 Preanalyze_Spec_Expression
5625 (Default_Value (New_Formal), Etype (New_Formal));
5629 if not (NewD and OldD)
5630 or else not Fully_Conformant_Expressions
5631 (Default_Value (Old_Formal),
5632 Default_Value (New_Formal))
5635 ("\default expression for & does not match!",
5644 -- A couple of special checks for Ada 83 mode. These checks are
5645 -- skipped if either entity is an operator in package Standard,
5646 -- or if either old or new instance is not from the source program.
5648 if Ada_Version = Ada_83
5649 and then Sloc (Old_Id) > Standard_Location
5650 and then Sloc (New_Id) > Standard_Location
5651 and then Comes_From_Source (Old_Id)
5652 and then Comes_From_Source (New_Id)
5655 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5656 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5659 -- Explicit IN must be present or absent in both cases. This
5660 -- test is required only in the full conformance case.
5662 if In_Present (Old_Param) /= In_Present (New_Param)
5663 and then Ctype = Fully_Conformant
5666 ("\(Ada 83) IN must appear in both declarations",
5671 -- Grouping (use of comma in param lists) must be the same
5672 -- This is where we catch a misconformance like:
5675 -- A : Integer; B : Integer
5677 -- which are represented identically in the tree except
5678 -- for the setting of the flags More_Ids and Prev_Ids.
5680 if More_Ids (Old_Param) /= More_Ids (New_Param)
5681 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5684 ("\grouping of & does not match!", New_Formal);
5690 -- This label is required when skipping controlling formals
5692 <<Skip_Controlling_Formal>>
5694 Next_Formal (Old_Formal);
5695 Next_Formal (New_Formal);
5698 if Present (Old_Formal) then
5699 Conformance_Error ("\too few parameters!");
5702 elsif Present (New_Formal) then
5703 Conformance_Error ("\too many parameters!", New_Formal);
5706 end Check_Conformance;
5708 -----------------------
5709 -- Check_Conventions --
5710 -----------------------
5712 procedure Check_Conventions (Typ : Entity_Id) is
5713 Ifaces_List : Elist_Id;
5715 procedure Check_Convention (Op : Entity_Id);
5716 -- Verify that the convention of inherited dispatching operation Op is
5717 -- consistent among all subprograms it overrides. In order to minimize
5718 -- the search, Search_From is utilized to designate a specific point in
5719 -- the list rather than iterating over the whole list once more.
5721 ----------------------
5722 -- Check_Convention --
5723 ----------------------
5725 procedure Check_Convention (Op : Entity_Id) is
5726 Op_Conv : constant Convention_Id := Convention (Op);
5727 Iface_Conv : Convention_Id;
5728 Iface_Elmt : Elmt_Id;
5729 Iface_Prim_Elmt : Elmt_Id;
5730 Iface_Prim : Entity_Id;
5733 Iface_Elmt := First_Elmt (Ifaces_List);
5734 while Present (Iface_Elmt) loop
5736 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5737 while Present (Iface_Prim_Elmt) loop
5738 Iface_Prim := Node (Iface_Prim_Elmt);
5739 Iface_Conv := Convention (Iface_Prim);
5741 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5742 and then Iface_Conv /= Op_Conv
5745 ("inconsistent conventions in primitive operations", Typ);
5747 Error_Msg_Name_1 := Chars (Op);
5748 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5749 Error_Msg_Sloc := Sloc (Op);
5751 if Comes_From_Source (Op) or else No (Alias (Op)) then
5752 if not Present (Overridden_Operation (Op)) then
5753 Error_Msg_N ("\\primitive % defined #", Typ);
5756 ("\\overriding operation % with "
5757 & "convention % defined #", Typ);
5760 else pragma Assert (Present (Alias (Op)));
5761 Error_Msg_Sloc := Sloc (Alias (Op));
5762 Error_Msg_N ("\\inherited operation % with "
5763 & "convention % defined #", Typ);
5766 Error_Msg_Name_1 := Chars (Op);
5767 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5768 Error_Msg_Sloc := Sloc (Iface_Prim);
5769 Error_Msg_N ("\\overridden operation % with "
5770 & "convention % defined #", Typ);
5772 -- Avoid cascading errors
5777 Next_Elmt (Iface_Prim_Elmt);
5780 Next_Elmt (Iface_Elmt);
5782 end Check_Convention;
5786 Prim_Op : Entity_Id;
5787 Prim_Op_Elmt : Elmt_Id;
5789 -- Start of processing for Check_Conventions
5792 if not Has_Interfaces (Typ) then
5796 Collect_Interfaces (Typ, Ifaces_List);
5798 -- The algorithm checks every overriding dispatching operation against
5799 -- all the corresponding overridden dispatching operations, detecting
5800 -- differences in conventions.
5802 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5803 while Present (Prim_Op_Elmt) loop
5804 Prim_Op := Node (Prim_Op_Elmt);
5806 -- A small optimization: skip the predefined dispatching operations
5807 -- since they always have the same convention.
5809 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5810 Check_Convention (Prim_Op);
5813 Next_Elmt (Prim_Op_Elmt);
5815 end Check_Conventions;
5817 ------------------------------
5818 -- Check_Delayed_Subprogram --
5819 ------------------------------
5821 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5824 procedure Possible_Freeze (T : Entity_Id);
5825 -- T is the type of either a formal parameter or of the return type.
5826 -- If T is not yet frozen and needs a delayed freeze, then the
5827 -- subprogram itself must be delayed.
5829 ---------------------
5830 -- Possible_Freeze --
5831 ---------------------
5833 procedure Possible_Freeze (T : Entity_Id) is
5835 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5836 Set_Has_Delayed_Freeze (Designator);
5838 elsif Is_Access_Type (T)
5839 and then Has_Delayed_Freeze (Designated_Type (T))
5840 and then not Is_Frozen (Designated_Type (T))
5842 Set_Has_Delayed_Freeze (Designator);
5845 end Possible_Freeze;
5847 -- Start of processing for Check_Delayed_Subprogram
5850 -- All subprograms, including abstract subprograms, may need a freeze
5851 -- node if some formal type or the return type needs one.
5853 Possible_Freeze (Etype (Designator));
5854 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5856 -- Need delayed freeze if any of the formal types themselves need
5857 -- a delayed freeze and are not yet frozen.
5859 F := First_Formal (Designator);
5860 while Present (F) loop
5861 Possible_Freeze (Etype (F));
5862 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5866 -- Mark functions that return by reference. Note that it cannot be
5867 -- done for delayed_freeze subprograms because the underlying
5868 -- returned type may not be known yet (for private types)
5870 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5872 Typ : constant Entity_Id := Etype (Designator);
5873 Utyp : constant Entity_Id := Underlying_Type (Typ);
5875 if Is_Limited_View (Typ) then
5876 Set_Returns_By_Ref (Designator);
5877 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5878 Set_Returns_By_Ref (Designator);
5882 end Check_Delayed_Subprogram;
5884 ------------------------------------
5885 -- Check_Discriminant_Conformance --
5886 ------------------------------------
5888 procedure Check_Discriminant_Conformance
5893 Old_Discr : Entity_Id := First_Discriminant (Prev);
5894 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5895 New_Discr_Id : Entity_Id;
5896 New_Discr_Type : Entity_Id;
5898 procedure Conformance_Error (Msg : String; N : Node_Id);
5899 -- Post error message for conformance error on given node. Two messages
5900 -- are output. The first points to the previous declaration with a
5901 -- general "no conformance" message. The second is the detailed reason,
5902 -- supplied as Msg. The parameter N provide information for a possible
5903 -- & insertion in the message.
5905 -----------------------
5906 -- Conformance_Error --
5907 -----------------------
5909 procedure Conformance_Error (Msg : String; N : Node_Id) is
5911 Error_Msg_Sloc := Sloc (Prev_Loc);
5912 Error_Msg_N -- CODEFIX
5913 ("not fully conformant with declaration#!", N);
5914 Error_Msg_NE (Msg, N, N);
5915 end Conformance_Error;
5917 -- Start of processing for Check_Discriminant_Conformance
5920 while Present (Old_Discr) and then Present (New_Discr) loop
5921 New_Discr_Id := Defining_Identifier (New_Discr);
5923 -- The subtype mark of the discriminant on the full type has not
5924 -- been analyzed so we do it here. For an access discriminant a new
5927 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5929 Access_Definition (N, Discriminant_Type (New_Discr));
5932 Analyze (Discriminant_Type (New_Discr));
5933 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5935 -- Ada 2005: if the discriminant definition carries a null
5936 -- exclusion, create an itype to check properly for consistency
5937 -- with partial declaration.
5939 if Is_Access_Type (New_Discr_Type)
5940 and then Null_Exclusion_Present (New_Discr)
5943 Create_Null_Excluding_Itype
5944 (T => New_Discr_Type,
5945 Related_Nod => New_Discr,
5946 Scope_Id => Current_Scope);
5950 if not Conforming_Types
5951 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5953 Conformance_Error ("type of & does not match!", New_Discr_Id);
5956 -- Treat the new discriminant as an occurrence of the old one,
5957 -- for navigation purposes, and fill in some semantic
5958 -- information, for completeness.
5960 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5961 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5962 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5967 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5968 Conformance_Error ("name & does not match!", New_Discr_Id);
5972 -- Default expressions must match
5975 NewD : constant Boolean :=
5976 Present (Expression (New_Discr));
5977 OldD : constant Boolean :=
5978 Present (Expression (Parent (Old_Discr)));
5981 if NewD or OldD then
5983 -- The old default value has been analyzed and expanded,
5984 -- because the current full declaration will have frozen
5985 -- everything before. The new default values have not been
5986 -- expanded, so expand now to check conformance.
5989 Preanalyze_Spec_Expression
5990 (Expression (New_Discr), New_Discr_Type);
5993 if not (NewD and OldD)
5994 or else not Fully_Conformant_Expressions
5995 (Expression (Parent (Old_Discr)),
5996 Expression (New_Discr))
6000 ("default expression for & does not match!",
6007 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6009 if Ada_Version = Ada_83 then
6011 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6014 -- Grouping (use of comma in param lists) must be the same
6015 -- This is where we catch a misconformance like:
6018 -- A : Integer; B : Integer
6020 -- which are represented identically in the tree except
6021 -- for the setting of the flags More_Ids and Prev_Ids.
6023 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6024 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6027 ("grouping of & does not match!", New_Discr_Id);
6033 Next_Discriminant (Old_Discr);
6037 if Present (Old_Discr) then
6038 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6041 elsif Present (New_Discr) then
6043 ("too many discriminants!", Defining_Identifier (New_Discr));
6046 end Check_Discriminant_Conformance;
6048 ----------------------------
6049 -- Check_Fully_Conformant --
6050 ----------------------------
6052 procedure Check_Fully_Conformant
6053 (New_Id : Entity_Id;
6055 Err_Loc : Node_Id := Empty)
6058 pragma Warnings (Off, Result);
6061 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6062 end Check_Fully_Conformant;
6064 --------------------------
6065 -- Check_Limited_Return --
6066 --------------------------
6068 procedure Check_Limited_Return
6074 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6075 -- replaced by anonymous access results. This is an incompatibility with
6076 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6077 -- controllable with special switch. ???
6079 -- A limited interface that is not immutably limited is OK
6081 if Is_Limited_Interface (R_Type)
6083 not (Is_Task_Interface (R_Type)
6084 or else Is_Protected_Interface (R_Type)
6085 or else Is_Synchronized_Interface (R_Type))
6089 elsif Is_Limited_Type (R_Type)
6090 and then not Is_Interface (R_Type)
6091 and then Comes_From_Source (N)
6092 and then not In_Instance_Body
6093 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6095 -- Error in Ada 2005
6097 if Ada_Version >= Ada_2005
6098 and then not Debug_Flag_Dot_L
6099 and then not GNAT_Mode
6102 ("(Ada 2005) cannot copy object of a limited type "
6103 & "(RM-2005 6.5(5.5/2))", Expr);
6105 if Is_Limited_View (R_Type) then
6107 ("\return by reference not permitted in Ada 2005", Expr);
6110 -- Warn in Ada 95 mode, to give folks a heads up about this
6113 -- In GNAT mode, this is just a warning, to allow it to be evilly
6114 -- turned off. Otherwise it is a real error.
6116 -- In a generic context, simplify the warning because it makes no
6117 -- sense to discuss pass-by-reference or copy.
6119 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6120 if Inside_A_Generic then
6122 ("return of limited object not permitted in Ada 2005 "
6123 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6125 elsif Is_Limited_View (R_Type) then
6127 ("return by reference not permitted in Ada 2005 "
6128 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6131 ("cannot copy object of a limited type in Ada 2005 "
6132 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6135 -- Ada 95 mode, and compatibility warnings disabled
6138 pragma Assert (Ada_Version <= Ada_95);
6139 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6140 return; -- skip continuation messages below
6143 if not Inside_A_Generic then
6145 ("\consider switching to return of access type", Expr);
6146 Explain_Limited_Type (R_Type, Expr);
6149 end Check_Limited_Return;
6151 ---------------------------
6152 -- Check_Mode_Conformant --
6153 ---------------------------
6155 procedure Check_Mode_Conformant
6156 (New_Id : Entity_Id;
6158 Err_Loc : Node_Id := Empty;
6159 Get_Inst : Boolean := False)
6162 pragma Warnings (Off, Result);
6165 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6166 end Check_Mode_Conformant;
6168 --------------------------------
6169 -- Check_Overriding_Indicator --
6170 --------------------------------
6172 procedure Check_Overriding_Indicator
6174 Overridden_Subp : Entity_Id;
6175 Is_Primitive : Boolean)
6181 -- No overriding indicator for literals
6183 if Ekind (Subp) = E_Enumeration_Literal then
6186 elsif Ekind (Subp) = E_Entry then
6187 Decl := Parent (Subp);
6189 -- No point in analyzing a malformed operator
6191 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6192 and then Error_Posted (Subp)
6197 Decl := Unit_Declaration_Node (Subp);
6200 if Nkind_In (Decl, N_Subprogram_Body,
6201 N_Subprogram_Body_Stub,
6202 N_Subprogram_Declaration,
6203 N_Abstract_Subprogram_Declaration,
6204 N_Subprogram_Renaming_Declaration)
6206 Spec := Specification (Decl);
6208 elsif Nkind (Decl) = N_Entry_Declaration then
6215 -- The overriding operation is type conformant with the overridden one,
6216 -- but the names of the formals are not required to match. If the names
6217 -- appear permuted in the overriding operation, this is a possible
6218 -- source of confusion that is worth diagnosing. Controlling formals
6219 -- often carry names that reflect the type, and it is not worthwhile
6220 -- requiring that their names match.
6222 if Present (Overridden_Subp)
6223 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6230 Form1 := First_Formal (Subp);
6231 Form2 := First_Formal (Overridden_Subp);
6233 -- If the overriding operation is a synchronized operation, skip
6234 -- the first parameter of the overridden operation, which is
6235 -- implicit in the new one. If the operation is declared in the
6236 -- body it is not primitive and all formals must match.
6238 if Is_Concurrent_Type (Scope (Subp))
6239 and then Is_Tagged_Type (Scope (Subp))
6240 and then not Has_Completion (Scope (Subp))
6242 Form2 := Next_Formal (Form2);
6245 if Present (Form1) then
6246 Form1 := Next_Formal (Form1);
6247 Form2 := Next_Formal (Form2);
6250 while Present (Form1) loop
6251 if not Is_Controlling_Formal (Form1)
6252 and then Present (Next_Formal (Form2))
6253 and then Chars (Form1) = Chars (Next_Formal (Form2))
6255 Error_Msg_Node_2 := Alias (Overridden_Subp);
6256 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6258 ("& does not match corresponding formal of&#",
6263 Next_Formal (Form1);
6264 Next_Formal (Form2);
6269 -- If there is an overridden subprogram, then check that there is no
6270 -- "not overriding" indicator, and mark the subprogram as overriding.
6271 -- This is not done if the overridden subprogram is marked as hidden,
6272 -- which can occur for the case of inherited controlled operations
6273 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6274 -- subprogram is not itself hidden. (Note: This condition could probably
6275 -- be simplified, leaving out the testing for the specific controlled
6276 -- cases, but it seems safer and clearer this way, and echoes similar
6277 -- special-case tests of this kind in other places.)
6279 if Present (Overridden_Subp)
6280 and then (not Is_Hidden (Overridden_Subp)
6282 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6285 and then Present (Alias (Overridden_Subp))
6286 and then not Is_Hidden (Alias (Overridden_Subp))))
6288 if Must_Not_Override (Spec) then
6289 Error_Msg_Sloc := Sloc (Overridden_Subp);
6291 if Ekind (Subp) = E_Entry then
6293 ("entry & overrides inherited operation #", Spec, Subp);
6296 ("subprogram & overrides inherited operation #", Spec, Subp);
6299 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6300 -- as an extension of Root_Controlled, and thus has a useless Adjust
6301 -- operation. This operation should not be inherited by other limited
6302 -- controlled types. An explicit Adjust for them is not overriding.
6304 elsif Must_Override (Spec)
6305 and then Chars (Overridden_Subp) = Name_Adjust
6306 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6307 and then Present (Alias (Overridden_Subp))
6308 and then In_Predefined_Unit (Alias (Overridden_Subp))
6311 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6312 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6314 elsif Is_Subprogram (Subp) then
6315 if Is_Init_Proc (Subp) then
6318 elsif No (Overridden_Operation (Subp)) then
6320 -- For entities generated by Derive_Subprograms the overridden
6321 -- operation is the inherited primitive (which is available
6322 -- through the attribute alias)
6324 if (Is_Dispatching_Operation (Subp)
6325 or else Is_Dispatching_Operation (Overridden_Subp))
6326 and then not Comes_From_Source (Overridden_Subp)
6327 and then Find_Dispatching_Type (Overridden_Subp) =
6328 Find_Dispatching_Type (Subp)
6329 and then Present (Alias (Overridden_Subp))
6330 and then Comes_From_Source (Alias (Overridden_Subp))
6332 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6333 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6336 Set_Overridden_Operation (Subp, Overridden_Subp);
6337 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6342 -- If primitive flag is set or this is a protected operation, then
6343 -- the operation is overriding at the point of its declaration, so
6344 -- warn if necessary. Otherwise it may have been declared before the
6345 -- operation it overrides and no check is required.
6348 and then not Must_Override (Spec)
6349 and then (Is_Primitive
6350 or else Ekind (Scope (Subp)) = E_Protected_Type)
6352 Style.Missing_Overriding (Decl, Subp);
6355 -- If Subp is an operator, it may override a predefined operation, if
6356 -- it is defined in the same scope as the type to which it applies.
6357 -- In that case Overridden_Subp is empty because of our implicit
6358 -- representation for predefined operators. We have to check whether the
6359 -- signature of Subp matches that of a predefined operator. Note that
6360 -- first argument provides the name of the operator, and the second
6361 -- argument the signature that may match that of a standard operation.
6362 -- If the indicator is overriding, then the operator must match a
6363 -- predefined signature, because we know already that there is no
6364 -- explicit overridden operation.
6366 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6367 if Must_Not_Override (Spec) then
6369 -- If this is not a primitive or a protected subprogram, then
6370 -- "not overriding" is illegal.
6373 and then Ekind (Scope (Subp)) /= E_Protected_Type
6375 Error_Msg_N ("overriding indicator only allowed "
6376 & "if subprogram is primitive", Subp);
6378 elsif Can_Override_Operator (Subp) then
6380 ("subprogram& overrides predefined operator ", Spec, Subp);
6383 elsif Must_Override (Spec) then
6384 if No (Overridden_Operation (Subp))
6385 and then not Can_Override_Operator (Subp)
6387 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6390 elsif not Error_Posted (Subp)
6391 and then Style_Check
6392 and then Can_Override_Operator (Subp)
6393 and then not In_Predefined_Unit (Subp)
6395 -- If style checks are enabled, indicate that the indicator is
6396 -- missing. However, at the point of declaration, the type of
6397 -- which this is a primitive operation may be private, in which
6398 -- case the indicator would be premature.
6400 if Has_Private_Declaration (Etype (Subp))
6401 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6405 Style.Missing_Overriding (Decl, Subp);
6409 elsif Must_Override (Spec) then
6410 if Ekind (Subp) = E_Entry then
6411 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6413 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6416 -- If the operation is marked "not overriding" and it's not primitive
6417 -- then an error is issued, unless this is an operation of a task or
6418 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6419 -- has been specified have already been checked above.
6421 elsif Must_Not_Override (Spec)
6422 and then not Is_Primitive
6423 and then Ekind (Subp) /= E_Entry
6424 and then Ekind (Scope (Subp)) /= E_Protected_Type
6427 ("overriding indicator only allowed if subprogram is primitive",
6431 end Check_Overriding_Indicator;
6437 -- Note: this procedure needs to know far too much about how the expander
6438 -- messes with exceptions. The use of the flag Exception_Junk and the
6439 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6440 -- works, but is not very clean. It would be better if the expansion
6441 -- routines would leave Original_Node working nicely, and we could use
6442 -- Original_Node here to ignore all the peculiar expander messing ???
6444 procedure Check_Returns
6448 Proc : Entity_Id := Empty)
6452 procedure Check_Statement_Sequence (L : List_Id);
6453 -- Internal recursive procedure to check a list of statements for proper
6454 -- termination by a return statement (or a transfer of control or a
6455 -- compound statement that is itself internally properly terminated).
6457 ------------------------------
6458 -- Check_Statement_Sequence --
6459 ------------------------------
6461 procedure Check_Statement_Sequence (L : List_Id) is
6466 function Assert_False return Boolean;
6467 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6468 -- rewritten as a null statement when assertions are off. The assert
6469 -- is not active, but it is still enough to kill the warning.
6475 function Assert_False return Boolean is
6476 Orig : constant Node_Id := Original_Node (Last_Stm);
6479 if Nkind (Orig) = N_Pragma
6480 and then Pragma_Name (Orig) = Name_Assert
6481 and then not Error_Posted (Orig)
6484 Arg : constant Node_Id :=
6485 First (Pragma_Argument_Associations (Orig));
6486 Exp : constant Node_Id := Expression (Arg);
6488 return Nkind (Exp) = N_Identifier
6489 and then Chars (Exp) = Name_False;
6499 Raise_Exception_Call : Boolean;
6500 -- Set True if statement sequence terminated by Raise_Exception call
6501 -- or a Reraise_Occurrence call.
6503 -- Start of processing for Check_Statement_Sequence
6506 Raise_Exception_Call := False;
6508 -- Get last real statement
6510 Last_Stm := Last (L);
6512 -- Deal with digging out exception handler statement sequences that
6513 -- have been transformed by the local raise to goto optimization.
6514 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6515 -- optimization has occurred, we are looking at something like:
6518 -- original stmts in block
6522 -- goto L1; | omitted if No_Exception_Propagation
6527 -- goto L3; -- skip handler when exception not raised
6529 -- <<L1>> -- target label for local exception
6543 -- and what we have to do is to dig out the estmts1 and estmts2
6544 -- sequences (which were the original sequences of statements in
6545 -- the exception handlers) and check them.
6547 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6552 exit when Nkind (Stm) /= N_Block_Statement;
6553 exit when not Exception_Junk (Stm);
6556 exit when Nkind (Stm) /= N_Label;
6557 exit when not Exception_Junk (Stm);
6558 Check_Statement_Sequence
6559 (Statements (Handled_Statement_Sequence (Next (Stm))));
6564 exit when Nkind (Stm) /= N_Goto_Statement;
6565 exit when not Exception_Junk (Stm);
6569 -- Don't count pragmas
6571 while Nkind (Last_Stm) = N_Pragma
6573 -- Don't count call to SS_Release (can happen after Raise_Exception)
6576 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6578 Nkind (Name (Last_Stm)) = N_Identifier
6580 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6582 -- Don't count exception junk
6585 (Nkind_In (Last_Stm, N_Goto_Statement,
6587 N_Object_Declaration)
6588 and then Exception_Junk (Last_Stm))
6589 or else Nkind (Last_Stm) in N_Push_xxx_Label
6590 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6592 -- Inserted code, such as finalization calls, is irrelevant: we only
6593 -- need to check original source.
6595 or else Is_Rewrite_Insertion (Last_Stm)
6600 -- Here we have the "real" last statement
6602 Kind := Nkind (Last_Stm);
6604 -- Transfer of control, OK. Note that in the No_Return procedure
6605 -- case, we already diagnosed any explicit return statements, so
6606 -- we can treat them as OK in this context.
6608 if Is_Transfer (Last_Stm) then
6611 -- Check cases of explicit non-indirect procedure calls
6613 elsif Kind = N_Procedure_Call_Statement
6614 and then Is_Entity_Name (Name (Last_Stm))
6616 -- Check call to Raise_Exception procedure which is treated
6617 -- specially, as is a call to Reraise_Occurrence.
6619 -- We suppress the warning in these cases since it is likely that
6620 -- the programmer really does not expect to deal with the case
6621 -- of Null_Occurrence, and thus would find a warning about a
6622 -- missing return curious, and raising Program_Error does not
6623 -- seem such a bad behavior if this does occur.
6625 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6626 -- behavior will be to raise Constraint_Error (see AI-329).
6628 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6630 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6632 Raise_Exception_Call := True;
6634 -- For Raise_Exception call, test first argument, if it is
6635 -- an attribute reference for a 'Identity call, then we know
6636 -- that the call cannot possibly return.
6639 Arg : constant Node_Id :=
6640 Original_Node (First_Actual (Last_Stm));
6642 if Nkind (Arg) = N_Attribute_Reference
6643 and then Attribute_Name (Arg) = Name_Identity
6650 -- If statement, need to look inside if there is an else and check
6651 -- each constituent statement sequence for proper termination.
6653 elsif Kind = N_If_Statement
6654 and then Present (Else_Statements (Last_Stm))
6656 Check_Statement_Sequence (Then_Statements (Last_Stm));
6657 Check_Statement_Sequence (Else_Statements (Last_Stm));
6659 if Present (Elsif_Parts (Last_Stm)) then
6661 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6664 while Present (Elsif_Part) loop
6665 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6673 -- Case statement, check each case for proper termination
6675 elsif Kind = N_Case_Statement then
6679 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6680 while Present (Case_Alt) loop
6681 Check_Statement_Sequence (Statements (Case_Alt));
6682 Next_Non_Pragma (Case_Alt);
6688 -- Block statement, check its handled sequence of statements
6690 elsif Kind = N_Block_Statement then
6696 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6705 -- Loop statement. If there is an iteration scheme, we can definitely
6706 -- fall out of the loop. Similarly if there is an exit statement, we
6707 -- can fall out. In either case we need a following return.
6709 elsif Kind = N_Loop_Statement then
6710 if Present (Iteration_Scheme (Last_Stm))
6711 or else Has_Exit (Entity (Identifier (Last_Stm)))
6715 -- A loop with no exit statement or iteration scheme is either
6716 -- an infinite loop, or it has some other exit (raise/return).
6717 -- In either case, no warning is required.
6723 -- Timed entry call, check entry call and delay alternatives
6725 -- Note: in expanded code, the timed entry call has been converted
6726 -- to a set of expanded statements on which the check will work
6727 -- correctly in any case.
6729 elsif Kind = N_Timed_Entry_Call then
6731 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6732 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6735 -- If statement sequence of entry call alternative is missing,
6736 -- then we can definitely fall through, and we post the error
6737 -- message on the entry call alternative itself.
6739 if No (Statements (ECA)) then
6742 -- If statement sequence of delay alternative is missing, then
6743 -- we can definitely fall through, and we post the error
6744 -- message on the delay alternative itself.
6746 -- Note: if both ECA and DCA are missing the return, then we
6747 -- post only one message, should be enough to fix the bugs.
6748 -- If not we will get a message next time on the DCA when the
6751 elsif No (Statements (DCA)) then
6754 -- Else check both statement sequences
6757 Check_Statement_Sequence (Statements (ECA));
6758 Check_Statement_Sequence (Statements (DCA));
6763 -- Conditional entry call, check entry call and else part
6765 -- Note: in expanded code, the conditional entry call has been
6766 -- converted to a set of expanded statements on which the check
6767 -- will work correctly in any case.
6769 elsif Kind = N_Conditional_Entry_Call then
6771 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6774 -- If statement sequence of entry call alternative is missing,
6775 -- then we can definitely fall through, and we post the error
6776 -- message on the entry call alternative itself.
6778 if No (Statements (ECA)) then
6781 -- Else check statement sequence and else part
6784 Check_Statement_Sequence (Statements (ECA));
6785 Check_Statement_Sequence (Else_Statements (Last_Stm));
6791 -- If we fall through, issue appropriate message
6795 -- Kill warning if last statement is a raise exception call,
6796 -- or a pragma Assert (False). Note that with assertions enabled,
6797 -- such a pragma has been converted into a raise exception call
6798 -- already, so the Assert_False is for the assertions off case.
6800 if not Raise_Exception_Call and then not Assert_False then
6802 -- In GNATprove mode, it is an error to have a missing return
6804 Error_Msg_Warn := SPARK_Mode /= On;
6806 -- Issue error message or warning
6809 ("RETURN statement missing following this statement<<!",
6812 ("\Program_Error ]<<!", Last_Stm);
6815 -- Note: we set Err even though we have not issued a warning
6816 -- because we still have a case of a missing return. This is
6817 -- an extremely marginal case, probably will never be noticed
6818 -- but we might as well get it right.
6822 -- Otherwise we have the case of a procedure marked No_Return
6825 if not Raise_Exception_Call then
6826 if GNATprove_Mode then
6828 ("implied return after this statement would have raised "
6829 & "Program_Error", Last_Stm);
6831 -- In normal compilation mode, do not warn on a generated call
6832 -- (e.g. in the body of a renaming as completion).
6834 elsif Comes_From_Source (Last_Stm) then
6836 ("implied return after this statement will raise "
6837 & "Program_Error??", Last_Stm);
6840 Error_Msg_Warn := SPARK_Mode /= On;
6842 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6846 RE : constant Node_Id :=
6847 Make_Raise_Program_Error (Sloc (Last_Stm),
6848 Reason => PE_Implicit_Return);
6850 Insert_After (Last_Stm, RE);
6854 end Check_Statement_Sequence;
6856 -- Start of processing for Check_Returns
6860 Check_Statement_Sequence (Statements (HSS));
6862 if Present (Exception_Handlers (HSS)) then
6863 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6864 while Present (Handler) loop
6865 Check_Statement_Sequence (Statements (Handler));
6866 Next_Non_Pragma (Handler);
6871 ----------------------------
6872 -- Check_Subprogram_Order --
6873 ----------------------------
6875 procedure Check_Subprogram_Order (N : Node_Id) is
6877 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6878 -- This is used to check if S1 > S2 in the sense required by this test,
6879 -- for example nameab < namec, but name2 < name10.
6881 -----------------------------
6882 -- Subprogram_Name_Greater --
6883 -----------------------------
6885 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6890 -- Deal with special case where names are identical except for a
6891 -- numerical suffix. These are handled specially, taking the numeric
6892 -- ordering from the suffix into account.
6895 while S1 (L1) in '0' .. '9' loop
6900 while S2 (L2) in '0' .. '9' loop
6904 -- If non-numeric parts non-equal, do straight compare
6906 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6909 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6910 -- that a missing suffix is treated as numeric zero in this test.
6914 while L1 < S1'Last loop
6916 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6920 while L2 < S2'Last loop
6922 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6927 end Subprogram_Name_Greater;
6929 -- Start of processing for Check_Subprogram_Order
6932 -- Check body in alpha order if this is option
6935 and then Style_Check_Order_Subprograms
6936 and then Nkind (N) = N_Subprogram_Body
6937 and then Comes_From_Source (N)
6938 and then In_Extended_Main_Source_Unit (N)
6942 renames Scope_Stack.Table
6943 (Scope_Stack.Last).Last_Subprogram_Name;
6945 Body_Id : constant Entity_Id :=
6946 Defining_Entity (Specification (N));
6949 Get_Decoded_Name_String (Chars (Body_Id));
6952 if Subprogram_Name_Greater
6953 (LSN.all, Name_Buffer (1 .. Name_Len))
6955 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6961 LSN := new String'(Name_Buffer (1 .. Name_Len));
6964 end Check_Subprogram_Order;
6966 ------------------------------
6967 -- Check_Subtype_Conformant --
6968 ------------------------------
6970 procedure Check_Subtype_Conformant
6971 (New_Id : Entity_Id;
6973 Err_Loc : Node_Id := Empty;
6974 Skip_Controlling_Formals : Boolean := False;
6975 Get_Inst : Boolean := False)
6978 pragma Warnings (Off, Result);
6981 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6982 Skip_Controlling_Formals => Skip_Controlling_Formals,
6983 Get_Inst => Get_Inst);
6984 end Check_Subtype_Conformant;
6986 -----------------------------------
6987 -- Check_Synchronized_Overriding --
6988 -----------------------------------
6990 procedure Check_Synchronized_Overriding
6991 (Def_Id : Entity_Id;
6992 Overridden_Subp : out Entity_Id)
6994 Ifaces_List : Elist_Id;
6998 function Matches_Prefixed_View_Profile
6999 (Prim_Params : List_Id;
7000 Iface_Params : List_Id) return Boolean;
7001 -- Determine whether a subprogram's parameter profile Prim_Params
7002 -- matches that of a potentially overridden interface subprogram
7003 -- Iface_Params. Also determine if the type of first parameter of
7004 -- Iface_Params is an implemented interface.
7006 -----------------------------------
7007 -- Matches_Prefixed_View_Profile --
7008 -----------------------------------
7010 function Matches_Prefixed_View_Profile
7011 (Prim_Params : List_Id;
7012 Iface_Params : List_Id) return Boolean
7014 function Is_Implemented
7015 (Ifaces_List : Elist_Id;
7016 Iface : Entity_Id) return Boolean;
7017 -- Determine if Iface is implemented by the current task or
7020 --------------------
7021 -- Is_Implemented --
7022 --------------------
7024 function Is_Implemented
7025 (Ifaces_List : Elist_Id;
7026 Iface : Entity_Id) return Boolean
7028 Iface_Elmt : Elmt_Id;
7031 Iface_Elmt := First_Elmt (Ifaces_List);
7032 while Present (Iface_Elmt) loop
7033 if Node (Iface_Elmt) = Iface then
7037 Next_Elmt (Iface_Elmt);
7045 Iface_Id : Entity_Id;
7046 Iface_Param : Node_Id;
7047 Iface_Typ : Entity_Id;
7048 Prim_Id : Entity_Id;
7049 Prim_Param : Node_Id;
7050 Prim_Typ : Entity_Id;
7052 -- Start of processing for Matches_Prefixed_View_Profile
7055 Iface_Param := First (Iface_Params);
7056 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7058 if Is_Access_Type (Iface_Typ) then
7059 Iface_Typ := Designated_Type (Iface_Typ);
7062 Prim_Param := First (Prim_Params);
7064 -- The first parameter of the potentially overridden subprogram must
7065 -- be an interface implemented by Prim.
7067 if not Is_Interface (Iface_Typ)
7068 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7073 -- The checks on the object parameters are done, so move on to the
7074 -- rest of the parameters.
7076 if not In_Scope then
7077 Prim_Param := Next (Prim_Param);
7080 Iface_Param := Next (Iface_Param);
7081 while Present (Iface_Param) and then Present (Prim_Param) loop
7082 Iface_Id := Defining_Identifier (Iface_Param);
7083 Iface_Typ := Find_Parameter_Type (Iface_Param);
7085 Prim_Id := Defining_Identifier (Prim_Param);
7086 Prim_Typ := Find_Parameter_Type (Prim_Param);
7088 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7089 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7090 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7092 Iface_Typ := Designated_Type (Iface_Typ);
7093 Prim_Typ := Designated_Type (Prim_Typ);
7096 -- Case of multiple interface types inside a parameter profile
7098 -- (Obj_Param : in out Iface; ...; Param : Iface)
7100 -- If the interface type is implemented, then the matching type in
7101 -- the primitive should be the implementing record type.
7103 if Ekind (Iface_Typ) = E_Record_Type
7104 and then Is_Interface (Iface_Typ)
7105 and then Is_Implemented (Ifaces_List, Iface_Typ)
7107 if Prim_Typ /= Typ then
7111 -- The two parameters must be both mode and subtype conformant
7113 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7115 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7124 -- One of the two lists contains more parameters than the other
7126 if Present (Iface_Param) or else Present (Prim_Param) then
7131 end Matches_Prefixed_View_Profile;
7133 -- Start of processing for Check_Synchronized_Overriding
7136 Overridden_Subp := Empty;
7138 -- Def_Id must be an entry or a subprogram. We should skip predefined
7139 -- primitives internally generated by the front end; however at this
7140 -- stage predefined primitives are still not fully decorated. As a
7141 -- minor optimization we skip here internally generated subprograms.
7143 if (Ekind (Def_Id) /= E_Entry
7144 and then Ekind (Def_Id) /= E_Function
7145 and then Ekind (Def_Id) /= E_Procedure)
7146 or else not Comes_From_Source (Def_Id)
7151 -- Search for the concurrent declaration since it contains the list of
7152 -- all implemented interfaces. In this case, the subprogram is declared
7153 -- within the scope of a protected or a task type.
7155 if Present (Scope (Def_Id))
7156 and then Is_Concurrent_Type (Scope (Def_Id))
7157 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7159 Typ := Scope (Def_Id);
7162 -- The enclosing scope is not a synchronized type and the subprogram
7165 elsif No (First_Formal (Def_Id)) then
7168 -- The subprogram has formals and hence it may be a primitive of a
7172 Typ := Etype (First_Formal (Def_Id));
7174 if Is_Access_Type (Typ) then
7175 Typ := Directly_Designated_Type (Typ);
7178 if Is_Concurrent_Type (Typ)
7179 and then not Is_Generic_Actual_Type (Typ)
7183 -- This case occurs when the concurrent type is declared within a
7184 -- generic unit. As a result the corresponding record has been built
7185 -- and used as the type of the first formal, we just have to retrieve
7186 -- the corresponding concurrent type.
7188 elsif Is_Concurrent_Record_Type (Typ)
7189 and then not Is_Class_Wide_Type (Typ)
7190 and then Present (Corresponding_Concurrent_Type (Typ))
7192 Typ := Corresponding_Concurrent_Type (Typ);
7200 -- There is no overriding to check if this is an inherited operation in
7201 -- a type derivation for a generic actual.
7203 Collect_Interfaces (Typ, Ifaces_List);
7205 if Is_Empty_Elmt_List (Ifaces_List) then
7209 -- Determine whether entry or subprogram Def_Id overrides a primitive
7210 -- operation that belongs to one of the interfaces in Ifaces_List.
7213 Candidate : Entity_Id := Empty;
7214 Hom : Entity_Id := Empty;
7215 Subp : Entity_Id := Empty;
7218 -- Traverse the homonym chain, looking for a potentially overridden
7219 -- subprogram that belongs to an implemented interface.
7221 Hom := Current_Entity_In_Scope (Def_Id);
7222 while Present (Hom) loop
7226 or else not Is_Overloadable (Subp)
7227 or else not Is_Primitive (Subp)
7228 or else not Is_Dispatching_Operation (Subp)
7229 or else not Present (Find_Dispatching_Type (Subp))
7230 or else not Is_Interface (Find_Dispatching_Type (Subp))
7234 -- Entries and procedures can override abstract or null interface
7237 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7238 and then Ekind (Subp) = E_Procedure
7239 and then Matches_Prefixed_View_Profile
7240 (Parameter_Specifications (Parent (Def_Id)),
7241 Parameter_Specifications (Parent (Subp)))
7245 -- For an overridden subprogram Subp, check whether the mode
7246 -- of its first parameter is correct depending on the kind of
7247 -- synchronized type.
7250 Formal : constant Node_Id := First_Formal (Candidate);
7253 -- In order for an entry or a protected procedure to
7254 -- override, the first parameter of the overridden routine
7255 -- must be of mode "out", "in out", or access-to-variable.
7257 if Ekind_In (Candidate, E_Entry, E_Procedure)
7258 and then Is_Protected_Type (Typ)
7259 and then Ekind (Formal) /= E_In_Out_Parameter
7260 and then Ekind (Formal) /= E_Out_Parameter
7261 and then Nkind (Parameter_Type (Parent (Formal))) /=
7266 -- All other cases are OK since a task entry or routine does
7267 -- not have a restriction on the mode of the first parameter
7268 -- of the overridden interface routine.
7271 Overridden_Subp := Candidate;
7276 -- Functions can override abstract interface functions
7278 elsif Ekind (Def_Id) = E_Function
7279 and then Ekind (Subp) = E_Function
7280 and then Matches_Prefixed_View_Profile
7281 (Parameter_Specifications (Parent (Def_Id)),
7282 Parameter_Specifications (Parent (Subp)))
7283 and then Etype (Def_Id) = Etype (Subp)
7287 -- If an inherited subprogram is implemented by a protected
7288 -- function, then the first parameter of the inherited
7289 -- subprogram shall be of mode in, but not an access-to-
7290 -- variable parameter (RM 9.4(11/9)).
7292 if Present (First_Formal (Subp))
7293 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7295 (not Is_Access_Type (Etype (First_Formal (Subp)))
7297 Is_Access_Constant (Etype (First_Formal (Subp))))
7299 Overridden_Subp := Subp;
7304 Hom := Homonym (Hom);
7307 -- After examining all candidates for overriding, we are left with
7308 -- the best match, which is a mode-incompatible interface routine.
7310 if In_Scope and then Present (Candidate) then
7311 Error_Msg_PT (Def_Id, Candidate);
7314 Overridden_Subp := Candidate;
7317 end Check_Synchronized_Overriding;
7319 ---------------------------
7320 -- Check_Type_Conformant --
7321 ---------------------------
7323 procedure Check_Type_Conformant
7324 (New_Id : Entity_Id;
7326 Err_Loc : Node_Id := Empty)
7329 pragma Warnings (Off, Result);
7332 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7333 end Check_Type_Conformant;
7335 ---------------------------
7336 -- Can_Override_Operator --
7337 ---------------------------
7339 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7343 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7347 Typ := Base_Type (Etype (First_Formal (Subp)));
7349 -- Check explicitly that the operation is a primitive of the type
7351 return Operator_Matches_Spec (Subp, Subp)
7352 and then not Is_Generic_Type (Typ)
7353 and then Scope (Subp) = Scope (Typ)
7354 and then not Is_Class_Wide_Type (Typ);
7356 end Can_Override_Operator;
7358 ----------------------
7359 -- Conforming_Types --
7360 ----------------------
7362 function Conforming_Types
7365 Ctype : Conformance_Type;
7366 Get_Inst : Boolean := False) return Boolean
7368 function Base_Types_Match
7370 Typ_2 : Entity_Id) return Boolean;
7371 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7372 -- in different scopes (e.g. parent and child instances), then verify
7373 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7374 -- the same subtype chain. The whole purpose of this procedure is to
7375 -- prevent spurious ambiguities in an instantiation that may arise if
7376 -- two distinct generic types are instantiated with the same actual.
7378 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7379 -- An access parameter can designate an incomplete type. If the
7380 -- incomplete type is the limited view of a type from a limited_
7381 -- with_clause, check whether the non-limited view is available.
7382 -- If it is a (non-limited) incomplete type, get the full view.
7384 function Matches_Limited_With_View
7386 Typ_2 : Entity_Id) return Boolean;
7387 -- Returns True if and only if either Typ_1 denotes a limited view of
7388 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7389 -- the limited with view of a type is used in a subprogram declaration
7390 -- and the subprogram body is in the scope of a regular with clause for
7391 -- the same unit. In such a case, the two type entities are considered
7392 -- identical for purposes of conformance checking.
7394 ----------------------
7395 -- Base_Types_Match --
7396 ----------------------
7398 function Base_Types_Match
7400 Typ_2 : Entity_Id) return Boolean
7402 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7403 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7406 if Typ_1 = Typ_2 then
7409 elsif Base_1 = Base_2 then
7411 -- The following is too permissive. A more precise test should
7412 -- check that the generic actual is an ancestor subtype of the
7415 -- See code in Find_Corresponding_Spec that applies an additional
7416 -- filter to handle accidental amiguities in instances.
7419 not Is_Generic_Actual_Type (Typ_1)
7420 or else not Is_Generic_Actual_Type (Typ_2)
7421 or else Scope (Typ_1) /= Scope (Typ_2);
7423 -- If Typ_2 is a generic actual type it is declared as the subtype of
7424 -- the actual. If that actual is itself a subtype we need to use its
7425 -- own base type to check for compatibility.
7427 elsif Ekind (Base_2) = Ekind (Typ_2)
7428 and then Base_1 = Base_Type (Base_2)
7432 elsif Ekind (Base_1) = Ekind (Typ_1)
7433 and then Base_2 = Base_Type (Base_1)
7440 end Base_Types_Match;
7442 --------------------------
7443 -- Find_Designated_Type --
7444 --------------------------
7446 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7450 Desig := Directly_Designated_Type (Typ);
7452 if Ekind (Desig) = E_Incomplete_Type then
7454 -- If regular incomplete type, get full view if available
7456 if Present (Full_View (Desig)) then
7457 Desig := Full_View (Desig);
7459 -- If limited view of a type, get non-limited view if available,
7460 -- and check again for a regular incomplete type.
7462 elsif Present (Non_Limited_View (Desig)) then
7463 Desig := Get_Full_View (Non_Limited_View (Desig));
7468 end Find_Designated_Type;
7470 -------------------------------
7471 -- Matches_Limited_With_View --
7472 -------------------------------
7474 function Matches_Limited_With_View
7476 Typ_2 : Entity_Id) return Boolean
7478 function Is_Matching_Limited_View
7480 View : Entity_Id) return Boolean;
7481 -- Determine whether non-limited view View denotes type Typ in some
7482 -- conformant fashion.
7484 ------------------------------
7485 -- Is_Matching_Limited_View --
7486 ------------------------------
7488 function Is_Matching_Limited_View
7490 View : Entity_Id) return Boolean
7492 Root_Typ : Entity_Id;
7493 Root_View : Entity_Id;
7496 -- The non-limited view directly denotes the type
7501 -- The type is a subtype of the non-limited view
7503 elsif Is_Subtype_Of (Typ, View) then
7506 -- Both the non-limited view and the type denote class-wide types
7508 elsif Is_Class_Wide_Type (Typ)
7509 and then Is_Class_Wide_Type (View)
7511 Root_Typ := Root_Type (Typ);
7512 Root_View := Root_Type (View);
7514 if Root_Typ = Root_View then
7517 -- An incomplete tagged type and its full view may receive two
7518 -- distinct class-wide types when the related package has not
7519 -- been analyzed yet.
7522 -- type T is tagged; -- CW_1
7523 -- type T is tagged null record; -- CW_2
7526 -- This is because the package lacks any semantic information
7527 -- that may eventually link both views of T. As a consequence,
7528 -- a client of the limited view of Pack will see CW_2 while a
7529 -- client of the non-limited view of Pack will see CW_1.
7531 elsif Is_Incomplete_Type (Root_Typ)
7532 and then Present (Full_View (Root_Typ))
7533 and then Full_View (Root_Typ) = Root_View
7537 elsif Is_Incomplete_Type (Root_View)
7538 and then Present (Full_View (Root_View))
7539 and then Full_View (Root_View) = Root_Typ
7546 end Is_Matching_Limited_View;
7548 -- Start of processing for Matches_Limited_With_View
7551 -- In some cases a type imported through a limited_with clause, and
7552 -- its non-limited view are both visible, for example in an anonymous
7553 -- access-to-class-wide type in a formal, or when building the body
7554 -- for a subprogram renaming after the subprogram has been frozen.
7555 -- In these cases both entities designate the same type. In addition,
7556 -- if one of them is an actual in an instance, it may be a subtype of
7557 -- the non-limited view of the other.
7559 if From_Limited_With (Typ_1)
7560 and then From_Limited_With (Typ_2)
7561 and then Available_View (Typ_1) = Available_View (Typ_2)
7565 elsif From_Limited_With (Typ_1) then
7566 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7568 elsif From_Limited_With (Typ_2) then
7569 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7574 end Matches_Limited_With_View;
7578 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7580 Type_1 : Entity_Id := T1;
7581 Type_2 : Entity_Id := T2;
7583 -- Start of processing for Conforming_Types
7586 -- The context is an instance association for a formal access-to-
7587 -- subprogram type; the formal parameter types require mapping because
7588 -- they may denote other formal parameters of the generic unit.
7591 Type_1 := Get_Instance_Of (T1);
7592 Type_2 := Get_Instance_Of (T2);
7595 -- If one of the types is a view of the other introduced by a limited
7596 -- with clause, treat these as conforming for all purposes.
7598 if Matches_Limited_With_View (T1, T2) then
7601 elsif Base_Types_Match (Type_1, Type_2) then
7602 if Ctype <= Mode_Conformant then
7607 Subtypes_Statically_Match (Type_1, Type_2)
7608 and then Dimensions_Match (Type_1, Type_2);
7611 elsif Is_Incomplete_Or_Private_Type (Type_1)
7612 and then Present (Full_View (Type_1))
7613 and then Base_Types_Match (Full_View (Type_1), Type_2)
7616 Ctype <= Mode_Conformant
7617 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7619 elsif Ekind (Type_2) = E_Incomplete_Type
7620 and then Present (Full_View (Type_2))
7621 and then Base_Types_Match (Type_1, Full_View (Type_2))
7624 Ctype <= Mode_Conformant
7625 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7627 elsif Is_Private_Type (Type_2)
7628 and then In_Instance
7629 and then Present (Full_View (Type_2))
7630 and then Base_Types_Match (Type_1, Full_View (Type_2))
7633 Ctype <= Mode_Conformant
7634 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7636 -- Another confusion between views in a nested instance with an
7637 -- actual private type whose full view is not in scope.
7639 elsif Ekind (Type_2) = E_Private_Subtype
7640 and then In_Instance
7641 and then Etype (Type_2) = Type_1
7645 -- In Ada 2012, incomplete types (including limited views) can appear
7646 -- as actuals in instantiations.
7648 elsif Is_Incomplete_Type (Type_1)
7649 and then Is_Incomplete_Type (Type_2)
7650 and then (Used_As_Generic_Actual (Type_1)
7651 or else Used_As_Generic_Actual (Type_2))
7656 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7657 -- treated recursively because they carry a signature. As far as
7658 -- conformance is concerned, convention plays no role, and either
7659 -- or both could be access to protected subprograms.
7661 Are_Anonymous_Access_To_Subprogram_Types :=
7662 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7663 E_Anonymous_Access_Protected_Subprogram_Type)
7665 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7666 E_Anonymous_Access_Protected_Subprogram_Type);
7668 -- Test anonymous access type case. For this case, static subtype
7669 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7670 -- the base types because we may have built internal subtype entities
7671 -- to handle null-excluding types (see Process_Formals).
7673 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7675 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7677 -- Ada 2005 (AI-254)
7679 or else Are_Anonymous_Access_To_Subprogram_Types
7682 Desig_1 : Entity_Id;
7683 Desig_2 : Entity_Id;
7686 -- In Ada 2005, access constant indicators must match for
7687 -- subtype conformance.
7689 if Ada_Version >= Ada_2005
7690 and then Ctype >= Subtype_Conformant
7692 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7697 Desig_1 := Find_Designated_Type (Type_1);
7698 Desig_2 := Find_Designated_Type (Type_2);
7700 -- If the context is an instance association for a formal
7701 -- access-to-subprogram type; formal access parameter designated
7702 -- types require mapping because they may denote other formal
7703 -- parameters of the generic unit.
7706 Desig_1 := Get_Instance_Of (Desig_1);
7707 Desig_2 := Get_Instance_Of (Desig_2);
7710 -- It is possible for a Class_Wide_Type to be introduced for an
7711 -- incomplete type, in which case there is a separate class_ wide
7712 -- type for the full view. The types conform if their Etypes
7713 -- conform, i.e. one may be the full view of the other. This can
7714 -- only happen in the context of an access parameter, other uses
7715 -- of an incomplete Class_Wide_Type are illegal.
7717 if Is_Class_Wide_Type (Desig_1)
7719 Is_Class_Wide_Type (Desig_2)
7723 (Etype (Base_Type (Desig_1)),
7724 Etype (Base_Type (Desig_2)), Ctype);
7726 elsif Are_Anonymous_Access_To_Subprogram_Types then
7727 if Ada_Version < Ada_2005 then
7729 Ctype = Type_Conformant
7730 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7732 -- We must check the conformance of the signatures themselves
7736 Conformant : Boolean;
7739 (Desig_1, Desig_2, Ctype, False, Conformant);
7744 -- A limited view of an actual matches the corresponding
7745 -- incomplete formal.
7747 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7748 and then From_Limited_With (Desig_2)
7749 and then Used_As_Generic_Actual (Etype (Desig_2))
7754 return Base_Type (Desig_1) = Base_Type (Desig_2)
7755 and then (Ctype = Type_Conformant
7757 Subtypes_Statically_Match (Desig_1, Desig_2));
7761 -- Otherwise definitely no match
7764 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7765 and then Is_Access_Type (Type_2))
7766 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7767 and then Is_Access_Type (Type_1)))
7770 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7772 May_Hide_Profile := True;
7777 end Conforming_Types;
7779 --------------------------
7780 -- Create_Extra_Formals --
7781 --------------------------
7783 procedure Create_Extra_Formals (E : Entity_Id) is
7784 First_Extra : Entity_Id := Empty;
7786 Last_Extra : Entity_Id := Empty;
7788 function Add_Extra_Formal
7789 (Assoc_Entity : Entity_Id;
7792 Suffix : String) return Entity_Id;
7793 -- Add an extra formal to the current list of formals and extra formals.
7794 -- The extra formal is added to the end of the list of extra formals,
7795 -- and also returned as the result. These formals are always of mode IN.
7796 -- The new formal has the type Typ, is declared in Scope, and its name
7797 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7798 -- The following suffixes are currently used. They should not be changed
7799 -- without coordinating with CodePeer, which makes use of these to
7800 -- provide better messages.
7802 -- O denotes the Constrained bit.
7803 -- L denotes the accessibility level.
7804 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7805 -- the full list in exp_ch6.BIP_Formal_Kind.
7807 ----------------------
7808 -- Add_Extra_Formal --
7809 ----------------------
7811 function Add_Extra_Formal
7812 (Assoc_Entity : Entity_Id;
7815 Suffix : String) return Entity_Id
7817 EF : constant Entity_Id :=
7818 Make_Defining_Identifier (Sloc (Assoc_Entity),
7819 Chars => New_External_Name (Chars (Assoc_Entity),
7823 -- A little optimization. Never generate an extra formal for the
7824 -- _init operand of an initialization procedure, since it could
7827 if Chars (Formal) = Name_uInit then
7831 Set_Ekind (EF, E_In_Parameter);
7832 Set_Actual_Subtype (EF, Typ);
7833 Set_Etype (EF, Typ);
7834 Set_Scope (EF, Scope);
7835 Set_Mechanism (EF, Default_Mechanism);
7836 Set_Formal_Validity (EF);
7838 if No (First_Extra) then
7840 Set_Extra_Formals (Scope, First_Extra);
7843 if Present (Last_Extra) then
7844 Set_Extra_Formal (Last_Extra, EF);
7850 end Add_Extra_Formal;
7854 Formal_Type : Entity_Id;
7855 P_Formal : Entity_Id := Empty;
7857 -- Start of processing for Create_Extra_Formals
7860 -- We never generate extra formals if expansion is not active because we
7861 -- don't need them unless we are generating code.
7863 if not Expander_Active then
7867 -- No need to generate extra formals in interface thunks whose target
7868 -- primitive has no extra formals.
7870 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7874 -- If this is a derived subprogram then the subtypes of the parent
7875 -- subprogram's formal parameters will be used to determine the need
7876 -- for extra formals.
7878 if Is_Overloadable (E) and then Present (Alias (E)) then
7879 P_Formal := First_Formal (Alias (E));
7882 Formal := First_Formal (E);
7883 while Present (Formal) loop
7884 Last_Extra := Formal;
7885 Next_Formal (Formal);
7888 -- If Extra_Formals were already created, don't do it again. This
7889 -- situation may arise for subprogram types created as part of
7890 -- dispatching calls (see Expand_Dispatching_Call)
7892 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7896 -- If the subprogram is a predefined dispatching subprogram then don't
7897 -- generate any extra constrained or accessibility level formals. In
7898 -- general we suppress these for internal subprograms (by not calling
7899 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7900 -- generated stream attributes do get passed through because extra
7901 -- build-in-place formals are needed in some cases (limited 'Input).
7903 if Is_Predefined_Internal_Operation (E) then
7904 goto Test_For_Func_Result_Extras;
7907 Formal := First_Formal (E);
7908 while Present (Formal) loop
7910 -- Create extra formal for supporting the attribute 'Constrained.
7911 -- The case of a private type view without discriminants also
7912 -- requires the extra formal if the underlying type has defaulted
7915 if Ekind (Formal) /= E_In_Parameter then
7916 if Present (P_Formal) then
7917 Formal_Type := Etype (P_Formal);
7919 Formal_Type := Etype (Formal);
7922 -- Do not produce extra formals for Unchecked_Union parameters.
7923 -- Jump directly to the end of the loop.
7925 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7926 goto Skip_Extra_Formal_Generation;
7929 if not Has_Discriminants (Formal_Type)
7930 and then Ekind (Formal_Type) in Private_Kind
7931 and then Present (Underlying_Type (Formal_Type))
7933 Formal_Type := Underlying_Type (Formal_Type);
7936 -- Suppress the extra formal if formal's subtype is constrained or
7937 -- indefinite, or we're compiling for Ada 2012 and the underlying
7938 -- type is tagged and limited. In Ada 2012, a limited tagged type
7939 -- can have defaulted discriminants, but 'Constrained is required
7940 -- to return True, so the formal is never needed (see AI05-0214).
7941 -- Note that this ensures consistency of calling sequences for
7942 -- dispatching operations when some types in a class have defaults
7943 -- on discriminants and others do not (and requiring the extra
7944 -- formal would introduce distributed overhead).
7946 -- If the type does not have a completion yet, treat as prior to
7947 -- Ada 2012 for consistency.
7949 if Has_Discriminants (Formal_Type)
7950 and then not Is_Constrained (Formal_Type)
7951 and then Is_Definite_Subtype (Formal_Type)
7952 and then (Ada_Version < Ada_2012
7953 or else No (Underlying_Type (Formal_Type))
7955 (Is_Limited_Type (Formal_Type)
7958 (Underlying_Type (Formal_Type)))))
7960 Set_Extra_Constrained
7961 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7965 -- Create extra formal for supporting accessibility checking. This
7966 -- is done for both anonymous access formals and formals of named
7967 -- access types that are marked as controlling formals. The latter
7968 -- case can occur when Expand_Dispatching_Call creates a subprogram
7969 -- type and substitutes the types of access-to-class-wide actuals
7970 -- for the anonymous access-to-specific-type of controlling formals.
7971 -- Base_Type is applied because in cases where there is a null
7972 -- exclusion the formal may have an access subtype.
7974 -- This is suppressed if we specifically suppress accessibility
7975 -- checks at the package level for either the subprogram, or the
7976 -- package in which it resides. However, we do not suppress it
7977 -- simply if the scope has accessibility checks suppressed, since
7978 -- this could cause trouble when clients are compiled with a
7979 -- different suppression setting. The explicit checks at the
7980 -- package level are safe from this point of view.
7982 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7983 or else (Is_Controlling_Formal (Formal)
7984 and then Is_Access_Type (Base_Type (Etype (Formal)))))
7986 (Explicit_Suppress (E, Accessibility_Check)
7988 Explicit_Suppress (Scope (E), Accessibility_Check))
7991 or else Present (Extra_Accessibility (P_Formal)))
7993 Set_Extra_Accessibility
7994 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
7997 -- This label is required when skipping extra formal generation for
7998 -- Unchecked_Union parameters.
8000 <<Skip_Extra_Formal_Generation>>
8002 if Present (P_Formal) then
8003 Next_Formal (P_Formal);
8006 Next_Formal (Formal);
8009 <<Test_For_Func_Result_Extras>>
8011 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8012 -- function call is ... determined by the point of call ...".
8014 if Needs_Result_Accessibility_Level (E) then
8015 Set_Extra_Accessibility_Of_Result
8016 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8019 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8020 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8022 if Is_Build_In_Place_Function (E) then
8024 Result_Subt : constant Entity_Id := Etype (E);
8025 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8026 Formal_Typ : Entity_Id;
8027 Subp_Decl : Node_Id;
8029 Discard : Entity_Id;
8030 pragma Warnings (Off, Discard);
8033 -- In the case of functions with unconstrained result subtypes,
8034 -- add a 4-state formal indicating whether the return object is
8035 -- allocated by the caller (1), or should be allocated by the
8036 -- callee on the secondary stack (2), in the global heap (3), or
8037 -- in a user-defined storage pool (4). For the moment we just use
8038 -- Natural for the type of this formal. Note that this formal
8039 -- isn't usually needed in the case where the result subtype is
8040 -- constrained, but it is needed when the function has a tagged
8041 -- result, because generally such functions can be called in a
8042 -- dispatching context and such calls must be handled like calls
8043 -- to a class-wide function.
8045 if Needs_BIP_Alloc_Form (E) then
8048 (E, Standard_Natural,
8049 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8051 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8052 -- use a user-defined pool. This formal is not added on
8053 -- ZFP as those targets do not support pools.
8055 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8058 (E, RTE (RE_Root_Storage_Pool_Ptr),
8059 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8063 -- In the case of functions whose result type needs finalization,
8064 -- add an extra formal which represents the finalization master.
8066 if Needs_BIP_Finalization_Master (E) then
8069 (E, RTE (RE_Finalization_Master_Ptr),
8070 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8073 -- When the result type contains tasks, add two extra formals: the
8074 -- master of the tasks to be created, and the caller's activation
8077 if Has_Task (Full_Subt) then
8080 (E, RTE (RE_Master_Id),
8081 E, BIP_Formal_Suffix (BIP_Task_Master));
8084 (E, RTE (RE_Activation_Chain_Access),
8085 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8088 -- All build-in-place functions get an extra formal that will be
8089 -- passed the address of the return object within the caller.
8092 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8094 Set_Directly_Designated_Type (Formal_Typ, Result_Subt);
8095 Set_Etype (Formal_Typ, Formal_Typ);
8096 Set_Depends_On_Private
8097 (Formal_Typ, Has_Private_Component (Formal_Typ));
8098 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8099 Set_Is_Access_Constant (Formal_Typ, False);
8101 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8102 -- the designated type comes from the limited view (for back-end
8105 Set_From_Limited_With
8106 (Formal_Typ, From_Limited_With (Result_Subt));
8108 Layout_Type (Formal_Typ);
8110 -- Force the definition of the Itype in case of internal function
8111 -- calls within the same or nested scope.
8113 if Is_Subprogram_Or_Generic_Subprogram (E) then
8114 Subp_Decl := Parent (E);
8116 -- The insertion point for an Itype reference should be after
8117 -- the unit declaration node of the subprogram. An exception
8118 -- to this are inherited operations from a parent type in which
8119 -- case the derived type acts as their parent.
8121 if Nkind_In (Subp_Decl, N_Function_Specification,
8122 N_Procedure_Specification)
8124 Subp_Decl := Parent (Subp_Decl);
8127 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8132 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8135 end Create_Extra_Formals;
8137 -----------------------------
8138 -- Enter_Overloaded_Entity --
8139 -----------------------------
8141 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8142 function Matches_Predefined_Op return Boolean;
8143 -- This returns an approximation of whether S matches a predefined
8144 -- operator, based on the operator symbol, and the parameter and result
8145 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8147 ---------------------------
8148 -- Matches_Predefined_Op --
8149 ---------------------------
8151 function Matches_Predefined_Op return Boolean is
8152 Formal_1 : constant Entity_Id := First_Formal (S);
8153 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8154 Op : constant Name_Id := Chars (S);
8155 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8156 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8161 if Present (Formal_2) then
8163 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8166 -- All but "&" and "**" have same-types parameters
8175 if Type_1 /= Type_2 then
8180 -- Check parameter and result types
8188 Is_Boolean_Type (Result_Type)
8189 and then Result_Type = Type_1;
8195 Is_Integer_Type (Result_Type)
8196 and then Result_Type = Type_1;
8204 Is_Numeric_Type (Result_Type)
8205 and then Result_Type = Type_1;
8211 Is_Boolean_Type (Result_Type)
8212 and then not Is_Limited_Type (Type_1);
8220 Is_Boolean_Type (Result_Type)
8221 and then (Is_Array_Type (Type_1)
8222 or else Is_Scalar_Type (Type_1));
8224 when Name_Op_Concat =>
8225 return Is_Array_Type (Result_Type);
8227 when Name_Op_Expon =>
8229 (Is_Integer_Type (Result_Type)
8230 or else Is_Floating_Point_Type (Result_Type))
8231 and then Result_Type = Type_1
8232 and then Type_2 = Standard_Integer;
8235 raise Program_Error;
8248 Is_Numeric_Type (Result_Type)
8249 and then Result_Type = Type_1;
8253 Is_Boolean_Type (Result_Type)
8254 and then Result_Type = Type_1;
8257 raise Program_Error;
8260 end Matches_Predefined_Op;
8264 E : Entity_Id := Current_Entity_In_Scope (S);
8265 C_E : Entity_Id := Current_Entity (S);
8267 -- Start of processing for Enter_Overloaded_Entity
8271 Set_Has_Homonym (E);
8272 Set_Has_Homonym (S);
8275 Set_Is_Immediately_Visible (S);
8276 Set_Scope (S, Current_Scope);
8278 -- Chain new entity if front of homonym in current scope, so that
8279 -- homonyms are contiguous.
8281 if Present (E) and then E /= C_E then
8282 while Homonym (C_E) /= E loop
8283 C_E := Homonym (C_E);
8286 Set_Homonym (C_E, S);
8290 Set_Current_Entity (S);
8295 if Is_Inherited_Operation (S) then
8296 Append_Inherited_Subprogram (S);
8298 Append_Entity (S, Current_Scope);
8301 Set_Public_Status (S);
8303 if Debug_Flag_E then
8304 Write_Str ("New overloaded entity chain: ");
8305 Write_Name (Chars (S));
8308 while Present (E) loop
8309 Write_Str (" "); Write_Int (Int (E));
8316 -- Generate warning for hiding
8319 and then Comes_From_Source (S)
8320 and then In_Extended_Main_Source_Unit (S)
8327 -- Warn unless genuine overloading. Do not emit warning on
8328 -- hiding predefined operators in Standard (these are either an
8329 -- (artifact of our implicit declarations, or simple noise) but
8330 -- keep warning on a operator defined on a local subtype, because
8331 -- of the real danger that different operators may be applied in
8332 -- various parts of the program.
8334 -- Note that if E and S have the same scope, there is never any
8335 -- hiding. Either the two conflict, and the program is illegal,
8336 -- or S is overriding an implicit inherited subprogram.
8338 if Scope (E) /= Scope (S)
8339 and then (not Is_Overloadable (E)
8340 or else Subtype_Conformant (E, S))
8341 and then (Is_Immediately_Visible (E)
8342 or else Is_Potentially_Use_Visible (S))
8344 if Scope (E) = Standard_Standard then
8345 if Nkind (S) = N_Defining_Operator_Symbol
8346 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8348 and then Matches_Predefined_Op
8351 ("declaration of & hides predefined operator?h?", S);
8354 -- E not immediately within Standard
8357 Error_Msg_Sloc := Sloc (E);
8358 Error_Msg_N ("declaration of & hides one #?h?", S);
8363 end Enter_Overloaded_Entity;
8365 -----------------------------
8366 -- Check_Untagged_Equality --
8367 -----------------------------
8369 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8370 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8371 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8375 -- This check applies only if we have a subprogram declaration with an
8376 -- untagged record type.
8378 if Nkind (Decl) /= N_Subprogram_Declaration
8379 or else not Is_Record_Type (Typ)
8380 or else Is_Tagged_Type (Typ)
8385 -- In Ada 2012 case, we will output errors or warnings depending on
8386 -- the setting of debug flag -gnatd.E.
8388 if Ada_Version >= Ada_2012 then
8389 Error_Msg_Warn := Debug_Flag_Dot_EE;
8391 -- In earlier versions of Ada, nothing to do unless we are warning on
8392 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8395 if not Warn_On_Ada_2012_Compatibility then
8400 -- Cases where the type has already been frozen
8402 if Is_Frozen (Typ) then
8404 -- If the type is not declared in a package, or if we are in the body
8405 -- of the package or in some other scope, the new operation is not
8406 -- primitive, and therefore legal, though suspicious. Should we
8407 -- generate a warning in this case ???
8409 if Ekind (Scope (Typ)) /= E_Package
8410 or else Scope (Typ) /= Current_Scope
8414 -- If the type is a generic actual (sub)type, the operation is not
8415 -- primitive either because the base type is declared elsewhere.
8417 elsif Is_Generic_Actual_Type (Typ) then
8420 -- Here we have a definite error of declaration after freezing
8423 if Ada_Version >= Ada_2012 then
8425 ("equality operator must be declared before type & is "
8426 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8428 -- In Ada 2012 mode with error turned to warning, output one
8429 -- more warning to warn that the equality operation may not
8430 -- compose. This is the consequence of ignoring the error.
8432 if Error_Msg_Warn then
8433 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8438 ("equality operator must be declared before type& is "
8439 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8442 -- If we are in the package body, we could just move the
8443 -- declaration to the package spec, so add a message saying that.
8445 if In_Package_Body (Scope (Typ)) then
8446 if Ada_Version >= Ada_2012 then
8448 ("\move declaration to package spec<<", Eq_Op);
8451 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8454 -- Otherwise try to find the freezing point
8457 Obj_Decl := Next (Parent (Typ));
8458 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8459 if Nkind (Obj_Decl) = N_Object_Declaration
8460 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8462 -- Freezing point, output warnings
8464 if Ada_Version >= Ada_2012 then
8466 ("type& is frozen by declaration??", Obj_Decl, Typ);
8468 ("\an equality operator cannot be declared after "
8473 ("type& is frozen by declaration (Ada 2012)?y?",
8476 ("\an equality operator cannot be declared after "
8477 & "this point (Ada 2012)?y?",
8489 -- Here if type is not frozen yet. It is illegal to have a primitive
8490 -- equality declared in the private part if the type is visible.
8492 elsif not In_Same_List (Parent (Typ), Decl)
8493 and then not Is_Limited_Type (Typ)
8495 -- Shouldn't we give an RM reference here???
8497 if Ada_Version >= Ada_2012 then
8499 ("equality operator appears too late<<", Eq_Op);
8502 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8505 -- No error detected
8510 end Check_Untagged_Equality;
8512 -----------------------------
8513 -- Find_Corresponding_Spec --
8514 -----------------------------
8516 function Find_Corresponding_Spec
8518 Post_Error : Boolean := True) return Entity_Id
8520 Spec : constant Node_Id := Specification (N);
8521 Designator : constant Entity_Id := Defining_Entity (Spec);
8525 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8526 -- Even if fully conformant, a body may depend on a generic actual when
8527 -- the spec does not, or vice versa, in which case they were distinct
8528 -- entities in the generic.
8530 -------------------------------
8531 -- Different_Generic_Profile --
8532 -------------------------------
8534 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8537 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8538 -- Check that the types of corresponding formals have the same
8539 -- generic actual if any. We have to account for subtypes of a
8540 -- generic formal, declared between a spec and a body, which may
8541 -- appear distinct in an instance but matched in the generic, and
8542 -- the subtype may be used either in the spec or the body of the
8543 -- subprogram being checked.
8545 -------------------------
8546 -- Same_Generic_Actual --
8547 -------------------------
8549 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8551 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8552 -- Predicate to check whether S1 is a subtype of S2 in the source
8555 -------------------------
8556 -- Is_Declared_Subtype --
8557 -------------------------
8559 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8561 return Comes_From_Source (Parent (S1))
8562 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8563 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8564 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8565 end Is_Declared_Subtype;
8567 -- Start of processing for Same_Generic_Actual
8570 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8571 or else Is_Declared_Subtype (T1, T2)
8572 or else Is_Declared_Subtype (T2, T1);
8573 end Same_Generic_Actual;
8575 -- Start of processing for Different_Generic_Profile
8578 if not In_Instance then
8581 elsif Ekind (E) = E_Function
8582 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8587 F1 := First_Formal (Designator);
8588 F2 := First_Formal (E);
8589 while Present (F1) loop
8590 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8599 end Different_Generic_Profile;
8601 -- Start of processing for Find_Corresponding_Spec
8604 E := Current_Entity (Designator);
8605 while Present (E) loop
8607 -- We are looking for a matching spec. It must have the same scope,
8608 -- and the same name, and either be type conformant, or be the case
8609 -- of a library procedure spec and its body (which belong to one
8610 -- another regardless of whether they are type conformant or not).
8612 if Scope (E) = Current_Scope then
8613 if Current_Scope = Standard_Standard
8614 or else (Ekind (E) = Ekind (Designator)
8615 and then Type_Conformant (E, Designator))
8617 -- Within an instantiation, we know that spec and body are
8618 -- subtype conformant, because they were subtype conformant in
8619 -- the generic. We choose the subtype-conformant entity here as
8620 -- well, to resolve spurious ambiguities in the instance that
8621 -- were not present in the generic (i.e. when two different
8622 -- types are given the same actual). If we are looking for a
8623 -- spec to match a body, full conformance is expected.
8627 -- Inherit the convention and "ghostness" of the matching
8628 -- spec to ensure proper full and subtype conformance.
8630 Set_Convention (Designator, Convention (E));
8632 -- Skip past subprogram bodies and subprogram renamings that
8633 -- may appear to have a matching spec, but that aren't fully
8634 -- conformant with it. That can occur in cases where an
8635 -- actual type causes unrelated homographs in the instance.
8637 if Nkind_In (N, N_Subprogram_Body,
8638 N_Subprogram_Renaming_Declaration)
8639 and then Present (Homonym (E))
8640 and then not Fully_Conformant (Designator, E)
8644 elsif not Subtype_Conformant (Designator, E) then
8647 elsif Different_Generic_Profile (E) then
8652 -- Ada 2012 (AI05-0165): For internally generated bodies of
8653 -- null procedures locate the internally generated spec. We
8654 -- enforce mode conformance since a tagged type may inherit
8655 -- from interfaces several null primitives which differ only
8656 -- in the mode of the formals.
8658 if not (Comes_From_Source (E))
8659 and then Is_Null_Procedure (E)
8660 and then not Mode_Conformant (Designator, E)
8664 -- For null procedures coming from source that are completions,
8665 -- analysis of the generated body will establish the link.
8667 elsif Comes_From_Source (E)
8668 and then Nkind (Spec) = N_Procedure_Specification
8669 and then Null_Present (Spec)
8673 -- Expression functions can be completions, but cannot be
8674 -- completed by an explicit body.
8676 elsif Comes_From_Source (E)
8677 and then Comes_From_Source (N)
8678 and then Nkind (N) = N_Subprogram_Body
8679 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8680 N_Expression_Function
8682 Error_Msg_Sloc := Sloc (E);
8683 Error_Msg_N ("body conflicts with expression function#", N);
8686 elsif not Has_Completion (E) then
8687 if Nkind (N) /= N_Subprogram_Body_Stub then
8688 Set_Corresponding_Spec (N, E);
8691 Set_Has_Completion (E);
8694 elsif Nkind (Parent (N)) = N_Subunit then
8696 -- If this is the proper body of a subunit, the completion
8697 -- flag is set when analyzing the stub.
8701 -- If E is an internal function with a controlling result that
8702 -- was created for an operation inherited by a null extension,
8703 -- it may be overridden by a body without a previous spec (one
8704 -- more reason why these should be shunned). In that case we
8705 -- remove the generated body if present, because the current
8706 -- one is the explicit overriding.
8708 elsif Ekind (E) = E_Function
8709 and then Ada_Version >= Ada_2005
8710 and then not Comes_From_Source (E)
8711 and then Has_Controlling_Result (E)
8712 and then Is_Null_Extension (Etype (E))
8713 and then Comes_From_Source (Spec)
8715 Set_Has_Completion (E, False);
8718 and then Nkind (Parent (E)) = N_Function_Specification
8721 (Unit_Declaration_Node
8722 (Corresponding_Body (Unit_Declaration_Node (E))));
8726 -- If expansion is disabled, or if the wrapper function has
8727 -- not been generated yet, this a late body overriding an
8728 -- inherited operation, or it is an overriding by some other
8729 -- declaration before the controlling result is frozen. In
8730 -- either case this is a declaration of a new entity.
8736 -- If the body already exists, then this is an error unless
8737 -- the previous declaration is the implicit declaration of a
8738 -- derived subprogram. It is also legal for an instance to
8739 -- contain type conformant overloadable declarations (but the
8740 -- generic declaration may not), per 8.3(26/2).
8742 elsif No (Alias (E))
8743 and then not Is_Intrinsic_Subprogram (E)
8744 and then not In_Instance
8747 Error_Msg_Sloc := Sloc (E);
8749 if Is_Imported (E) then
8751 ("body not allowed for imported subprogram & declared#",
8754 Error_Msg_NE ("duplicate body for & declared#", N, E);
8758 -- Child units cannot be overloaded, so a conformance mismatch
8759 -- between body and a previous spec is an error.
8761 elsif Is_Child_Unit (E)
8763 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8765 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8770 ("body of child unit does not match previous declaration", N);
8778 -- On exit, we know that no previous declaration of subprogram exists
8781 end Find_Corresponding_Spec;
8783 ----------------------
8784 -- Fully_Conformant --
8785 ----------------------
8787 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8790 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8792 end Fully_Conformant;
8794 ----------------------------------
8795 -- Fully_Conformant_Expressions --
8796 ----------------------------------
8798 function Fully_Conformant_Expressions
8799 (Given_E1 : Node_Id;
8800 Given_E2 : Node_Id) return Boolean
8802 E1 : constant Node_Id := Original_Node (Given_E1);
8803 E2 : constant Node_Id := Original_Node (Given_E2);
8804 -- We always test conformance on original nodes, since it is possible
8805 -- for analysis and/or expansion to make things look as though they
8806 -- conform when they do not, e.g. by converting 1+2 into 3.
8808 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8809 renames Fully_Conformant_Expressions;
8811 function FCL (L1, L2 : List_Id) return Boolean;
8812 -- Compare elements of two lists for conformance. Elements have to be
8813 -- conformant, and actuals inserted as default parameters do not match
8814 -- explicit actuals with the same value.
8816 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8817 -- Compare an operator node with a function call
8823 function FCL (L1, L2 : List_Id) return Boolean is
8827 if L1 = No_List then
8833 if L2 = No_List then
8839 -- Compare two lists, skipping rewrite insertions (we want to compare
8840 -- the original trees, not the expanded versions).
8843 if Is_Rewrite_Insertion (N1) then
8845 elsif Is_Rewrite_Insertion (N2) then
8851 elsif not FCE (N1, N2) then
8864 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8865 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8870 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8875 Act := First (Actuals);
8877 if Nkind (Op_Node) in N_Binary_Op then
8878 if not FCE (Left_Opnd (Op_Node), Act) then
8885 return Present (Act)
8886 and then FCE (Right_Opnd (Op_Node), Act)
8887 and then No (Next (Act));
8891 -- Start of processing for Fully_Conformant_Expressions
8894 -- Nonconformant if paren count does not match. Note: if some idiot
8895 -- complains that we don't do this right for more than 3 levels of
8896 -- parentheses, they will be treated with the respect they deserve.
8898 if Paren_Count (E1) /= Paren_Count (E2) then
8901 -- If same entities are referenced, then they are conformant even if
8902 -- they have different forms (RM 8.3.1(19-20)).
8904 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8905 if Present (Entity (E1)) then
8906 return Entity (E1) = Entity (E2)
8908 -- One may be a discriminant that has been replaced by the
8909 -- corresponding discriminal.
8912 (Chars (Entity (E1)) = Chars (Entity (E2))
8913 and then Ekind (Entity (E1)) = E_Discriminant
8914 and then Ekind (Entity (E2)) = E_In_Parameter)
8916 -- The discriminant of a protected type is transformed into
8917 -- a local constant and then into a parameter of a protected
8921 (Ekind (Entity (E1)) = E_Constant
8922 and then Ekind (Entity (E2)) = E_In_Parameter
8923 and then Present (Discriminal_Link (Entity (E1)))
8924 and then Discriminal_Link (Entity (E1)) =
8925 Discriminal_Link (Entity (E2)))
8927 -- AI12-050: The loop variables of quantified expressions
8928 -- match if they have the same identifier, even though they
8929 -- are different entities.
8932 (Chars (Entity (E1)) = Chars (Entity (E2))
8933 and then Ekind (Entity (E1)) = E_Loop_Parameter
8934 and then Ekind (Entity (E2)) = E_Loop_Parameter);
8936 elsif Nkind (E1) = N_Expanded_Name
8937 and then Nkind (E2) = N_Expanded_Name
8938 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8939 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8941 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8944 -- Identifiers in component associations don't always have
8945 -- entities, but their names must conform.
8947 return Nkind (E1) = N_Identifier
8948 and then Nkind (E2) = N_Identifier
8949 and then Chars (E1) = Chars (E2);
8952 elsif Nkind (E1) = N_Character_Literal
8953 and then Nkind (E2) = N_Expanded_Name
8955 return Nkind (Selector_Name (E2)) = N_Character_Literal
8956 and then Chars (E1) = Chars (Selector_Name (E2));
8958 elsif Nkind (E2) = N_Character_Literal
8959 and then Nkind (E1) = N_Expanded_Name
8961 return Nkind (Selector_Name (E1)) = N_Character_Literal
8962 and then Chars (E2) = Chars (Selector_Name (E1));
8964 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8965 return FCO (E1, E2);
8967 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8968 return FCO (E2, E1);
8970 -- Otherwise we must have the same syntactic entity
8972 elsif Nkind (E1) /= Nkind (E2) then
8975 -- At this point, we specialize by node type
8981 FCL (Expressions (E1), Expressions (E2))
8983 FCL (Component_Associations (E1),
8984 Component_Associations (E2));
8987 if Nkind (Expression (E1)) = N_Qualified_Expression
8989 Nkind (Expression (E2)) = N_Qualified_Expression
8991 return FCE (Expression (E1), Expression (E2));
8993 -- Check that the subtype marks and any constraints
8998 Indic1 : constant Node_Id := Expression (E1);
8999 Indic2 : constant Node_Id := Expression (E2);
9004 if Nkind (Indic1) /= N_Subtype_Indication then
9006 Nkind (Indic2) /= N_Subtype_Indication
9007 and then Entity (Indic1) = Entity (Indic2);
9009 elsif Nkind (Indic2) /= N_Subtype_Indication then
9011 Nkind (Indic1) /= N_Subtype_Indication
9012 and then Entity (Indic1) = Entity (Indic2);
9015 if Entity (Subtype_Mark (Indic1)) /=
9016 Entity (Subtype_Mark (Indic2))
9021 Elt1 := First (Constraints (Constraint (Indic1)));
9022 Elt2 := First (Constraints (Constraint (Indic2)));
9023 while Present (Elt1) and then Present (Elt2) loop
9024 if not FCE (Elt1, Elt2) then
9037 when N_Attribute_Reference =>
9039 Attribute_Name (E1) = Attribute_Name (E2)
9040 and then FCL (Expressions (E1), Expressions (E2));
9044 Entity (E1) = Entity (E2)
9045 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9046 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9048 when N_Membership_Test
9052 FCE (Left_Opnd (E1), Left_Opnd (E2))
9054 FCE (Right_Opnd (E1), Right_Opnd (E2));
9056 when N_Case_Expression =>
9062 if not FCE (Expression (E1), Expression (E2)) then
9066 Alt1 := First (Alternatives (E1));
9067 Alt2 := First (Alternatives (E2));
9069 if Present (Alt1) /= Present (Alt2) then
9071 elsif No (Alt1) then
9075 if not FCE (Expression (Alt1), Expression (Alt2))
9076 or else not FCL (Discrete_Choices (Alt1),
9077 Discrete_Choices (Alt2))
9088 when N_Character_Literal =>
9090 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9092 when N_Component_Association =>
9094 FCL (Choices (E1), Choices (E2))
9096 FCE (Expression (E1), Expression (E2));
9098 when N_Explicit_Dereference =>
9100 FCE (Prefix (E1), Prefix (E2));
9102 when N_Extension_Aggregate =>
9104 FCL (Expressions (E1), Expressions (E2))
9105 and then Null_Record_Present (E1) =
9106 Null_Record_Present (E2)
9107 and then FCL (Component_Associations (E1),
9108 Component_Associations (E2));
9110 when N_Function_Call =>
9112 FCE (Name (E1), Name (E2))
9114 FCL (Parameter_Associations (E1),
9115 Parameter_Associations (E2));
9117 when N_If_Expression =>
9119 FCL (Expressions (E1), Expressions (E2));
9121 when N_Indexed_Component =>
9123 FCE (Prefix (E1), Prefix (E2))
9125 FCL (Expressions (E1), Expressions (E2));
9127 when N_Integer_Literal =>
9128 return (Intval (E1) = Intval (E2));
9133 when N_Operator_Symbol =>
9135 Chars (E1) = Chars (E2);
9137 when N_Others_Choice =>
9140 when N_Parameter_Association =>
9142 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9143 and then FCE (Explicit_Actual_Parameter (E1),
9144 Explicit_Actual_Parameter (E2));
9146 when N_Qualified_Expression
9148 | N_Unchecked_Type_Conversion
9151 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9153 FCE (Expression (E1), Expression (E2));
9155 when N_Quantified_Expression =>
9156 if not FCE (Condition (E1), Condition (E2)) then
9160 if Present (Loop_Parameter_Specification (E1))
9161 and then Present (Loop_Parameter_Specification (E2))
9164 L1 : constant Node_Id :=
9165 Loop_Parameter_Specification (E1);
9166 L2 : constant Node_Id :=
9167 Loop_Parameter_Specification (E2);
9171 Reverse_Present (L1) = Reverse_Present (L2)
9173 FCE (Defining_Identifier (L1),
9174 Defining_Identifier (L2))
9176 FCE (Discrete_Subtype_Definition (L1),
9177 Discrete_Subtype_Definition (L2));
9180 elsif Present (Iterator_Specification (E1))
9181 and then Present (Iterator_Specification (E2))
9184 I1 : constant Node_Id := Iterator_Specification (E1);
9185 I2 : constant Node_Id := Iterator_Specification (E2);
9189 FCE (Defining_Identifier (I1),
9190 Defining_Identifier (I2))
9192 Of_Present (I1) = Of_Present (I2)
9194 Reverse_Present (I1) = Reverse_Present (I2)
9195 and then FCE (Name (I1), Name (I2))
9196 and then FCE (Subtype_Indication (I1),
9197 Subtype_Indication (I2));
9200 -- The quantified expressions used different specifications to
9201 -- walk their respective ranges.
9209 FCE (Low_Bound (E1), Low_Bound (E2))
9211 FCE (High_Bound (E1), High_Bound (E2));
9213 when N_Real_Literal =>
9214 return (Realval (E1) = Realval (E2));
9216 when N_Selected_Component =>
9218 FCE (Prefix (E1), Prefix (E2))
9220 FCE (Selector_Name (E1), Selector_Name (E2));
9224 FCE (Prefix (E1), Prefix (E2))
9226 FCE (Discrete_Range (E1), Discrete_Range (E2));
9228 when N_String_Literal =>
9230 S1 : constant String_Id := Strval (E1);
9231 S2 : constant String_Id := Strval (E2);
9232 L1 : constant Nat := String_Length (S1);
9233 L2 : constant Nat := String_Length (S2);
9240 for J in 1 .. L1 loop
9241 if Get_String_Char (S1, J) /=
9242 Get_String_Char (S2, J)
9254 Entity (E1) = Entity (E2)
9256 FCE (Right_Opnd (E1), Right_Opnd (E2));
9258 -- All other node types cannot appear in this context. Strictly
9259 -- we should raise a fatal internal error. Instead we just ignore
9260 -- the nodes. This means that if anyone makes a mistake in the
9261 -- expander and mucks an expression tree irretrievably, the result
9262 -- will be a failure to detect a (probably very obscure) case
9263 -- of non-conformance, which is better than bombing on some
9264 -- case where two expressions do in fact conform.
9270 end Fully_Conformant_Expressions;
9272 ----------------------------------------
9273 -- Fully_Conformant_Discrete_Subtypes --
9274 ----------------------------------------
9276 function Fully_Conformant_Discrete_Subtypes
9277 (Given_S1 : Node_Id;
9278 Given_S2 : Node_Id) return Boolean
9280 S1 : constant Node_Id := Original_Node (Given_S1);
9281 S2 : constant Node_Id := Original_Node (Given_S2);
9283 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9284 -- Special-case for a bound given by a discriminant, which in the body
9285 -- is replaced with the discriminal of the enclosing type.
9287 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9288 -- Check both bounds
9290 -----------------------
9291 -- Conforming_Bounds --
9292 -----------------------
9294 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9296 if Is_Entity_Name (B1)
9297 and then Is_Entity_Name (B2)
9298 and then Ekind (Entity (B1)) = E_Discriminant
9300 return Chars (B1) = Chars (B2);
9303 return Fully_Conformant_Expressions (B1, B2);
9305 end Conforming_Bounds;
9307 -----------------------
9308 -- Conforming_Ranges --
9309 -----------------------
9311 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9314 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9316 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9317 end Conforming_Ranges;
9319 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9322 if Nkind (S1) /= Nkind (S2) then
9325 elsif Is_Entity_Name (S1) then
9326 return Entity (S1) = Entity (S2);
9328 elsif Nkind (S1) = N_Range then
9329 return Conforming_Ranges (S1, S2);
9331 elsif Nkind (S1) = N_Subtype_Indication then
9333 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9336 (Range_Expression (Constraint (S1)),
9337 Range_Expression (Constraint (S2)));
9341 end Fully_Conformant_Discrete_Subtypes;
9343 --------------------
9344 -- Install_Entity --
9345 --------------------
9347 procedure Install_Entity (E : Entity_Id) is
9348 Prev : constant Entity_Id := Current_Entity (E);
9350 Set_Is_Immediately_Visible (E);
9351 Set_Current_Entity (E);
9352 Set_Homonym (E, Prev);
9355 ---------------------
9356 -- Install_Formals --
9357 ---------------------
9359 procedure Install_Formals (Id : Entity_Id) is
9362 F := First_Formal (Id);
9363 while Present (F) loop
9367 end Install_Formals;
9369 -----------------------------
9370 -- Is_Interface_Conformant --
9371 -----------------------------
9373 function Is_Interface_Conformant
9374 (Tagged_Type : Entity_Id;
9375 Iface_Prim : Entity_Id;
9376 Prim : Entity_Id) return Boolean
9378 -- The operation may in fact be an inherited (implicit) operation
9379 -- rather than the original interface primitive, so retrieve the
9380 -- ultimate ancestor.
9382 Iface : constant Entity_Id :=
9383 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9384 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9386 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9387 -- Return the controlling formal of Prim
9389 ------------------------
9390 -- Controlling_Formal --
9391 ------------------------
9393 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9397 E := First_Entity (Prim);
9398 while Present (E) loop
9399 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9407 end Controlling_Formal;
9411 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9412 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9414 -- Start of processing for Is_Interface_Conformant
9417 pragma Assert (Is_Subprogram (Iface_Prim)
9418 and then Is_Subprogram (Prim)
9419 and then Is_Dispatching_Operation (Iface_Prim)
9420 and then Is_Dispatching_Operation (Prim));
9422 pragma Assert (Is_Interface (Iface)
9423 or else (Present (Alias (Iface_Prim))
9426 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9428 if Prim = Iface_Prim
9429 or else not Is_Subprogram (Prim)
9430 or else Ekind (Prim) /= Ekind (Iface_Prim)
9431 or else not Is_Dispatching_Operation (Prim)
9432 or else Scope (Prim) /= Scope (Tagged_Type)
9434 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9435 or else not Primitive_Names_Match (Iface_Prim, Prim)
9439 -- The mode of the controlling formals must match
9441 elsif Present (Iface_Ctrl_F)
9442 and then Present (Prim_Ctrl_F)
9443 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9447 -- Case of a procedure, or a function whose result type matches the
9448 -- result type of the interface primitive, or a function that has no
9449 -- controlling result (I or access I).
9451 elsif Ekind (Iface_Prim) = E_Procedure
9452 or else Etype (Prim) = Etype (Iface_Prim)
9453 or else not Has_Controlling_Result (Prim)
9455 return Type_Conformant
9456 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9458 -- Case of a function returning an interface, or an access to one. Check
9459 -- that the return types correspond.
9461 elsif Implements_Interface (Typ, Iface) then
9462 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9464 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9469 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9470 Skip_Controlling_Formals => True);
9476 end Is_Interface_Conformant;
9478 ---------------------------------
9479 -- Is_Non_Overriding_Operation --
9480 ---------------------------------
9482 function Is_Non_Overriding_Operation
9483 (Prev_E : Entity_Id;
9484 New_E : Entity_Id) return Boolean
9488 G_Typ : Entity_Id := Empty;
9490 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9491 -- If F_Type is a derived type associated with a generic actual subtype,
9492 -- then return its Generic_Parent_Type attribute, else return Empty.
9494 function Types_Correspond
9495 (P_Type : Entity_Id;
9496 N_Type : Entity_Id) return Boolean;
9497 -- Returns true if and only if the types (or designated types in the
9498 -- case of anonymous access types) are the same or N_Type is derived
9499 -- directly or indirectly from P_Type.
9501 -----------------------------
9502 -- Get_Generic_Parent_Type --
9503 -----------------------------
9505 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9511 if Is_Derived_Type (F_Typ)
9512 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9514 -- The tree must be traversed to determine the parent subtype in
9515 -- the generic unit, which unfortunately isn't always available
9516 -- via semantic attributes. ??? (Note: The use of Original_Node
9517 -- is needed for cases where a full derived type has been
9520 -- If the parent type is a scalar type, the derivation creates
9521 -- an anonymous base type for it, and the source type is its
9524 if Is_Scalar_Type (F_Typ)
9525 and then not Comes_From_Source (F_Typ)
9529 (Original_Node (Parent (First_Subtype (F_Typ))));
9531 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9533 if Nkind (Defn) = N_Derived_Type_Definition then
9534 Indic := Subtype_Indication (Defn);
9536 if Nkind (Indic) = N_Subtype_Indication then
9537 G_Typ := Entity (Subtype_Mark (Indic));
9539 G_Typ := Entity (Indic);
9542 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9543 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9545 return Generic_Parent_Type (Parent (G_Typ));
9551 end Get_Generic_Parent_Type;
9553 ----------------------
9554 -- Types_Correspond --
9555 ----------------------
9557 function Types_Correspond
9558 (P_Type : Entity_Id;
9559 N_Type : Entity_Id) return Boolean
9561 Prev_Type : Entity_Id := Base_Type (P_Type);
9562 New_Type : Entity_Id := Base_Type (N_Type);
9565 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9566 Prev_Type := Designated_Type (Prev_Type);
9569 if Ekind (New_Type) = E_Anonymous_Access_Type then
9570 New_Type := Designated_Type (New_Type);
9573 if Prev_Type = New_Type then
9576 elsif not Is_Class_Wide_Type (New_Type) then
9577 while Etype (New_Type) /= New_Type loop
9578 New_Type := Etype (New_Type);
9580 if New_Type = Prev_Type then
9586 end Types_Correspond;
9588 -- Start of processing for Is_Non_Overriding_Operation
9591 -- In the case where both operations are implicit derived subprograms
9592 -- then neither overrides the other. This can only occur in certain
9593 -- obscure cases (e.g., derivation from homographs created in a generic
9596 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9599 elsif Ekind (Current_Scope) = E_Package
9600 and then Is_Generic_Instance (Current_Scope)
9601 and then In_Private_Part (Current_Scope)
9602 and then Comes_From_Source (New_E)
9604 -- We examine the formals and result type of the inherited operation,
9605 -- to determine whether their type is derived from (the instance of)
9606 -- a generic type. The first such formal or result type is the one
9609 Formal := First_Formal (Prev_E);
9611 while Present (Formal) loop
9612 F_Typ := Base_Type (Etype (Formal));
9614 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9615 F_Typ := Designated_Type (F_Typ);
9618 G_Typ := Get_Generic_Parent_Type (F_Typ);
9619 exit when Present (G_Typ);
9621 Next_Formal (Formal);
9624 -- If the function dispatches on result check the result type
9626 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9627 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9634 -- If the generic type is a private type, then the original operation
9635 -- was not overriding in the generic, because there was no primitive
9636 -- operation to override.
9638 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9639 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9640 N_Formal_Private_Type_Definition
9644 -- The generic parent type is the ancestor of a formal derived
9645 -- type declaration. We need to check whether it has a primitive
9646 -- operation that should be overridden by New_E in the generic.
9650 P_Formal : Entity_Id;
9651 N_Formal : Entity_Id;
9655 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9658 while Present (Prim_Elt) loop
9659 P_Prim := Node (Prim_Elt);
9661 if Chars (P_Prim) = Chars (New_E)
9662 and then Ekind (P_Prim) = Ekind (New_E)
9664 P_Formal := First_Formal (P_Prim);
9665 N_Formal := First_Formal (New_E);
9666 while Present (P_Formal) and then Present (N_Formal) loop
9667 P_Typ := Etype (P_Formal);
9668 N_Typ := Etype (N_Formal);
9670 if not Types_Correspond (P_Typ, N_Typ) then
9674 Next_Entity (P_Formal);
9675 Next_Entity (N_Formal);
9678 -- Found a matching primitive operation belonging to the
9679 -- formal ancestor type, so the new subprogram is
9683 and then No (N_Formal)
9684 and then (Ekind (New_E) /= E_Function
9687 (Etype (P_Prim), Etype (New_E)))
9693 Next_Elmt (Prim_Elt);
9696 -- If no match found, then the new subprogram does not override
9697 -- in the generic (nor in the instance).
9699 -- If the type in question is not abstract, and the subprogram
9700 -- is, this will be an error if the new operation is in the
9701 -- private part of the instance. Emit a warning now, which will
9702 -- make the subsequent error message easier to understand.
9704 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9705 and then Is_Abstract_Subprogram (Prev_E)
9706 and then In_Private_Part (Current_Scope)
9708 Error_Msg_Node_2 := F_Typ;
9710 ("private operation& in generic unit does not override "
9711 & "any primitive operation of& (RM 12.3 (18))??",
9721 end Is_Non_Overriding_Operation;
9723 -------------------------------------
9724 -- List_Inherited_Pre_Post_Aspects --
9725 -------------------------------------
9727 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9729 if Opt.List_Inherited_Aspects
9730 and then Is_Subprogram_Or_Generic_Subprogram (E)
9733 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9738 for Index in Subps'Range loop
9739 Items := Contract (Subps (Index));
9741 if Present (Items) then
9742 Prag := Pre_Post_Conditions (Items);
9743 while Present (Prag) loop
9744 Error_Msg_Sloc := Sloc (Prag);
9746 if Class_Present (Prag)
9747 and then not Split_PPC (Prag)
9749 if Pragma_Name (Prag) = Name_Precondition then
9751 ("info: & inherits `Pre''Class` aspect from "
9755 ("info: & inherits `Post''Class` aspect from "
9760 Prag := Next_Pragma (Prag);
9766 end List_Inherited_Pre_Post_Aspects;
9768 ------------------------------
9769 -- Make_Inequality_Operator --
9770 ------------------------------
9772 -- S is the defining identifier of an equality operator. We build a
9773 -- subprogram declaration with the right signature. This operation is
9774 -- intrinsic, because it is always expanded as the negation of the
9775 -- call to the equality function.
9777 procedure Make_Inequality_Operator (S : Entity_Id) is
9778 Loc : constant Source_Ptr := Sloc (S);
9781 Op_Name : Entity_Id;
9783 FF : constant Entity_Id := First_Formal (S);
9784 NF : constant Entity_Id := Next_Formal (FF);
9787 -- Check that equality was properly defined, ignore call if not
9794 A : constant Entity_Id :=
9795 Make_Defining_Identifier (Sloc (FF),
9796 Chars => Chars (FF));
9798 B : constant Entity_Id :=
9799 Make_Defining_Identifier (Sloc (NF),
9800 Chars => Chars (NF));
9803 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9805 Formals := New_List (
9806 Make_Parameter_Specification (Loc,
9807 Defining_Identifier => A,
9809 New_Occurrence_Of (Etype (First_Formal (S)),
9810 Sloc (Etype (First_Formal (S))))),
9812 Make_Parameter_Specification (Loc,
9813 Defining_Identifier => B,
9815 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9816 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9819 Make_Subprogram_Declaration (Loc,
9821 Make_Function_Specification (Loc,
9822 Defining_Unit_Name => Op_Name,
9823 Parameter_Specifications => Formals,
9824 Result_Definition =>
9825 New_Occurrence_Of (Standard_Boolean, Loc)));
9827 -- Insert inequality right after equality if it is explicit or after
9828 -- the derived type when implicit. These entities are created only
9829 -- for visibility purposes, and eventually replaced in the course
9830 -- of expansion, so they do not need to be attached to the tree and
9831 -- seen by the back-end. Keeping them internal also avoids spurious
9832 -- freezing problems. The declaration is inserted in the tree for
9833 -- analysis, and removed afterwards. If the equality operator comes
9834 -- from an explicit declaration, attach the inequality immediately
9835 -- after. Else the equality is inherited from a derived type
9836 -- declaration, so insert inequality after that declaration.
9838 if No (Alias (S)) then
9839 Insert_After (Unit_Declaration_Node (S), Decl);
9840 elsif Is_List_Member (Parent (S)) then
9841 Insert_After (Parent (S), Decl);
9843 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9846 Mark_Rewrite_Insertion (Decl);
9847 Set_Is_Intrinsic_Subprogram (Op_Name);
9850 Set_Has_Completion (Op_Name);
9851 Set_Corresponding_Equality (Op_Name, S);
9852 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9854 end Make_Inequality_Operator;
9856 ----------------------
9857 -- May_Need_Actuals --
9858 ----------------------
9860 procedure May_Need_Actuals (Fun : Entity_Id) is
9865 F := First_Formal (Fun);
9867 while Present (F) loop
9868 if No (Default_Value (F)) then
9876 Set_Needs_No_Actuals (Fun, B);
9877 end May_Need_Actuals;
9879 ---------------------
9880 -- Mode_Conformant --
9881 ---------------------
9883 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9886 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9888 end Mode_Conformant;
9890 ---------------------------
9891 -- New_Overloaded_Entity --
9892 ---------------------------
9894 procedure New_Overloaded_Entity
9896 Derived_Type : Entity_Id := Empty)
9898 Overridden_Subp : Entity_Id := Empty;
9899 -- Set if the current scope has an operation that is type-conformant
9900 -- with S, and becomes hidden by S.
9902 Is_Primitive_Subp : Boolean;
9903 -- Set to True if the new subprogram is primitive
9906 -- Entity that S overrides
9908 Prev_Vis : Entity_Id := Empty;
9909 -- Predecessor of E in Homonym chain
9911 procedure Check_For_Primitive_Subprogram
9912 (Is_Primitive : out Boolean;
9913 Is_Overriding : Boolean := False);
9914 -- If the subprogram being analyzed is a primitive operation of the type
9915 -- of a formal or result, set the Has_Primitive_Operations flag on the
9916 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9917 -- corresponding flag on the entity itself for later use.
9919 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9920 -- True if a) E is a subprogram whose first formal is a concurrent type
9921 -- defined in the scope of E that has some entry or subprogram whose
9922 -- profile matches E, or b) E is an internally built dispatching
9923 -- subprogram of a protected type and there is a matching subprogram
9924 -- defined in the enclosing scope of the protected type, or c) E is
9925 -- an entry of a synchronized type and a matching procedure has been
9926 -- previously defined in the enclosing scope of the synchronized type.
9928 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9929 -- Check that E is declared in the private part of the current package,
9930 -- or in the package body, where it may hide a previous declaration.
9931 -- We can't use In_Private_Part by itself because this flag is also
9932 -- set when freezing entities, so we must examine the place of the
9933 -- declaration in the tree, and recognize wrapper packages as well.
9935 function Is_Overriding_Alias
9937 New_E : Entity_Id) return Boolean;
9938 -- Check whether new subprogram and old subprogram are both inherited
9939 -- from subprograms that have distinct dispatch table entries. This can
9940 -- occur with derivations from instances with accidental homonyms. The
9941 -- function is conservative given that the converse is only true within
9942 -- instances that contain accidental overloadings.
9944 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9945 -- Report conflict between entities S and E
9947 ------------------------------------
9948 -- Check_For_Primitive_Subprogram --
9949 ------------------------------------
9951 procedure Check_For_Primitive_Subprogram
9952 (Is_Primitive : out Boolean;
9953 Is_Overriding : Boolean := False)
9959 function Visible_Part_Type (T : Entity_Id) return Boolean;
9960 -- Returns true if T is declared in the visible part of the current
9961 -- package scope; otherwise returns false. Assumes that T is declared
9964 procedure Check_Private_Overriding (T : Entity_Id);
9965 -- Checks that if a primitive abstract subprogram of a visible
9966 -- abstract type is declared in a private part, then it must override
9967 -- an abstract subprogram declared in the visible part. Also checks
9968 -- that if a primitive function with a controlling result is declared
9969 -- in a private part, then it must override a function declared in
9970 -- the visible part.
9972 ------------------------------
9973 -- Check_Private_Overriding --
9974 ------------------------------
9976 procedure Check_Private_Overriding (T : Entity_Id) is
9977 function Overrides_Private_Part_Op return Boolean;
9978 -- This detects the special case where the overriding subprogram
9979 -- is overriding a subprogram that was declared in the same
9980 -- private part. That case is illegal by 3.9.3(10).
9982 function Overrides_Visible_Function
9983 (Partial_View : Entity_Id) return Boolean;
9984 -- True if S overrides a function in the visible part. The
9985 -- overridden function could be explicitly or implicitly declared.
9987 -------------------------------
9988 -- Overrides_Private_Part_Op --
9989 -------------------------------
9991 function Overrides_Private_Part_Op return Boolean is
9992 Over_Decl : constant Node_Id :=
9993 Unit_Declaration_Node (Overridden_Operation (S));
9994 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
9997 pragma Assert (Is_Overriding);
9999 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10001 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10003 return In_Same_List (Over_Decl, Subp_Decl);
10004 end Overrides_Private_Part_Op;
10006 --------------------------------
10007 -- Overrides_Visible_Function --
10008 --------------------------------
10010 function Overrides_Visible_Function
10011 (Partial_View : Entity_Id) return Boolean
10014 if not Is_Overriding or else not Has_Homonym (S) then
10018 if not Present (Partial_View) then
10022 -- Search through all the homonyms H of S in the current
10023 -- package spec, and return True if we find one that matches.
10024 -- Note that Parent (H) will be the declaration of the
10025 -- partial view of T for a match.
10028 H : Entity_Id := S;
10032 exit when not Present (H) or else Scope (H) /= Scope (S);
10036 N_Private_Extension_Declaration,
10037 N_Private_Type_Declaration)
10038 and then Defining_Identifier (Parent (H)) = Partial_View
10046 end Overrides_Visible_Function;
10048 -- Start of processing for Check_Private_Overriding
10051 if Is_Package_Or_Generic_Package (Current_Scope)
10052 and then In_Private_Part (Current_Scope)
10053 and then Visible_Part_Type (T)
10054 and then not In_Instance
10056 if Is_Abstract_Type (T)
10057 and then Is_Abstract_Subprogram (S)
10058 and then (not Is_Overriding
10059 or else not Is_Abstract_Subprogram (E)
10060 or else Overrides_Private_Part_Op)
10063 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10066 elsif Ekind (S) = E_Function then
10068 Partial_View : constant Entity_Id :=
10069 Incomplete_Or_Partial_View (T);
10072 if not Overrides_Visible_Function (Partial_View) then
10074 -- Here, S is "function ... return T;" declared in
10075 -- the private part, not overriding some visible
10076 -- operation. That's illegal in the tagged case
10077 -- (but not if the private type is untagged).
10079 if ((Present (Partial_View)
10080 and then Is_Tagged_Type (Partial_View))
10081 or else (not Present (Partial_View)
10082 and then Is_Tagged_Type (T)))
10083 and then T = Base_Type (Etype (S))
10086 ("private function with tagged result must"
10087 & " override visible-part function", S);
10089 ("\move subprogram to the visible part"
10090 & " (RM 3.9.3(10))", S);
10092 -- AI05-0073: extend this test to the case of a
10093 -- function with a controlling access result.
10095 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10096 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10098 not Is_Class_Wide_Type
10099 (Designated_Type (Etype (S)))
10100 and then Ada_Version >= Ada_2012
10103 ("private function with controlling access "
10104 & "result must override visible-part function",
10107 ("\move subprogram to the visible part"
10108 & " (RM 3.9.3(10))", S);
10114 end Check_Private_Overriding;
10116 -----------------------
10117 -- Visible_Part_Type --
10118 -----------------------
10120 function Visible_Part_Type (T : Entity_Id) return Boolean is
10121 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10124 -- If the entity is a private type, then it must be declared in a
10127 if Ekind (T) in Private_Kind then
10130 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10133 elsif Is_List_Member (Declaration_Node (T))
10134 and then List_Containing (Declaration_Node (T)) =
10135 Visible_Declarations (Specification (P))
10142 end Visible_Part_Type;
10144 -- Start of processing for Check_For_Primitive_Subprogram
10147 Is_Primitive := False;
10149 if not Comes_From_Source (S) then
10152 -- If subprogram is at library level, it is not primitive operation
10154 elsif Current_Scope = Standard_Standard then
10157 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10158 and then not In_Package_Body (Current_Scope))
10159 or else Is_Overriding
10161 -- For function, check return type
10163 if Ekind (S) = E_Function then
10164 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10165 F_Typ := Designated_Type (Etype (S));
10167 F_Typ := Etype (S);
10170 B_Typ := Base_Type (F_Typ);
10172 if Scope (B_Typ) = Current_Scope
10173 and then not Is_Class_Wide_Type (B_Typ)
10174 and then not Is_Generic_Type (B_Typ)
10176 Is_Primitive := True;
10177 Set_Has_Primitive_Operations (B_Typ);
10178 Set_Is_Primitive (S);
10179 Check_Private_Overriding (B_Typ);
10181 -- The Ghost policy in effect at the point of declaration
10182 -- or a tagged type and a primitive operation must match
10183 -- (SPARK RM 6.9(16)).
10185 Check_Ghost_Primitive (S, B_Typ);
10189 -- For all subprograms, check formals
10191 Formal := First_Formal (S);
10192 while Present (Formal) loop
10193 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10194 F_Typ := Designated_Type (Etype (Formal));
10196 F_Typ := Etype (Formal);
10199 B_Typ := Base_Type (F_Typ);
10201 if Ekind (B_Typ) = E_Access_Subtype then
10202 B_Typ := Base_Type (B_Typ);
10205 if Scope (B_Typ) = Current_Scope
10206 and then not Is_Class_Wide_Type (B_Typ)
10207 and then not Is_Generic_Type (B_Typ)
10209 Is_Primitive := True;
10210 Set_Is_Primitive (S);
10211 Set_Has_Primitive_Operations (B_Typ);
10212 Check_Private_Overriding (B_Typ);
10214 -- The Ghost policy in effect at the point of declaration
10215 -- of a tagged type and a primitive operation must match
10216 -- (SPARK RM 6.9(16)).
10218 Check_Ghost_Primitive (S, B_Typ);
10221 Next_Formal (Formal);
10224 -- Special case: An equality function can be redefined for a type
10225 -- occurring in a declarative part, and won't otherwise be treated as
10226 -- a primitive because it doesn't occur in a package spec and doesn't
10227 -- override an inherited subprogram. It's important that we mark it
10228 -- primitive so it can be returned by Collect_Primitive_Operations
10229 -- and be used in composing the equality operation of later types
10230 -- that have a component of the type.
10232 elsif Chars (S) = Name_Op_Eq
10233 and then Etype (S) = Standard_Boolean
10235 B_Typ := Base_Type (Etype (First_Formal (S)));
10237 if Scope (B_Typ) = Current_Scope
10239 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10240 and then not Is_Limited_Type (B_Typ)
10242 Is_Primitive := True;
10243 Set_Is_Primitive (S);
10244 Set_Has_Primitive_Operations (B_Typ);
10245 Check_Private_Overriding (B_Typ);
10247 -- The Ghost policy in effect at the point of declaration of a
10248 -- tagged type and a primitive operation must match
10249 -- (SPARK RM 6.9(16)).
10251 Check_Ghost_Primitive (S, B_Typ);
10254 end Check_For_Primitive_Subprogram;
10256 --------------------------------------
10257 -- Has_Matching_Entry_Or_Subprogram --
10258 --------------------------------------
10260 function Has_Matching_Entry_Or_Subprogram
10261 (E : Entity_Id) return Boolean
10263 function Check_Conforming_Parameters
10264 (E1_Param : Node_Id;
10265 E2_Param : Node_Id) return Boolean;
10266 -- Starting from the given parameters, check that all the parameters
10267 -- of two entries or subprograms are subtype conformant. Used to skip
10268 -- the check on the controlling argument.
10270 function Matching_Entry_Or_Subprogram
10271 (Conc_Typ : Entity_Id;
10272 Subp : Entity_Id) return Entity_Id;
10273 -- Return the first entry or subprogram of the given concurrent type
10274 -- whose name matches the name of Subp and has a profile conformant
10275 -- with Subp; return Empty if not found.
10277 function Matching_Dispatching_Subprogram
10278 (Conc_Typ : Entity_Id;
10279 Ent : Entity_Id) return Entity_Id;
10280 -- Return the first dispatching primitive of Conc_Type defined in the
10281 -- enclosing scope of Conc_Type (i.e. before the full definition of
10282 -- this concurrent type) whose name matches the entry Ent and has a
10283 -- profile conformant with the profile of the corresponding (not yet
10284 -- built) dispatching primitive of Ent; return Empty if not found.
10286 function Matching_Original_Protected_Subprogram
10287 (Prot_Typ : Entity_Id;
10288 Subp : Entity_Id) return Entity_Id;
10289 -- Return the first subprogram defined in the enclosing scope of
10290 -- Prot_Typ (before the full definition of this protected type)
10291 -- whose name matches the original name of Subp and has a profile
10292 -- conformant with the profile of Subp; return Empty if not found.
10294 ---------------------------------
10295 -- Check_Confirming_Parameters --
10296 ---------------------------------
10298 function Check_Conforming_Parameters
10299 (E1_Param : Node_Id;
10300 E2_Param : Node_Id) return Boolean
10302 Param_E1 : Node_Id := E1_Param;
10303 Param_E2 : Node_Id := E2_Param;
10306 while Present (Param_E1) and then Present (Param_E2) loop
10307 if Ekind (Defining_Identifier (Param_E1)) /=
10308 Ekind (Defining_Identifier (Param_E2))
10311 (Find_Parameter_Type (Param_E1),
10312 Find_Parameter_Type (Param_E2),
10313 Subtype_Conformant)
10322 -- The candidate is not valid if one of the two lists contains
10323 -- more parameters than the other
10325 return No (Param_E1) and then No (Param_E2);
10326 end Check_Conforming_Parameters;
10328 ----------------------------------
10329 -- Matching_Entry_Or_Subprogram --
10330 ----------------------------------
10332 function Matching_Entry_Or_Subprogram
10333 (Conc_Typ : Entity_Id;
10334 Subp : Entity_Id) return Entity_Id
10339 E := First_Entity (Conc_Typ);
10340 while Present (E) loop
10341 if Chars (Subp) = Chars (E)
10342 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10344 Check_Conforming_Parameters
10345 (First (Parameter_Specifications (Parent (E))),
10346 Next (First (Parameter_Specifications (Parent (Subp)))))
10355 end Matching_Entry_Or_Subprogram;
10357 -------------------------------------
10358 -- Matching_Dispatching_Subprogram --
10359 -------------------------------------
10361 function Matching_Dispatching_Subprogram
10362 (Conc_Typ : Entity_Id;
10363 Ent : Entity_Id) return Entity_Id
10368 -- Search for entities in the enclosing scope of this synchonized
10371 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10372 Push_Scope (Scope (Conc_Typ));
10373 E := Current_Entity_In_Scope (Ent);
10376 while Present (E) loop
10377 if Scope (E) = Scope (Conc_Typ)
10378 and then Comes_From_Source (E)
10379 and then Ekind (E) = E_Procedure
10380 and then Present (First_Entity (E))
10381 and then Is_Controlling_Formal (First_Entity (E))
10382 and then Etype (First_Entity (E)) = Conc_Typ
10384 Check_Conforming_Parameters
10385 (First (Parameter_Specifications (Parent (Ent))),
10386 Next (First (Parameter_Specifications (Parent (E)))))
10395 end Matching_Dispatching_Subprogram;
10397 --------------------------------------------
10398 -- Matching_Original_Protected_Subprogram --
10399 --------------------------------------------
10401 function Matching_Original_Protected_Subprogram
10402 (Prot_Typ : Entity_Id;
10403 Subp : Entity_Id) return Entity_Id
10405 ICF : constant Boolean :=
10406 Is_Controlling_Formal (First_Entity (Subp));
10410 -- Temporarily decorate the first parameter of Subp as controlling
10411 -- formal, required to invoke Subtype_Conformant.
10413 Set_Is_Controlling_Formal (First_Entity (Subp));
10416 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10418 while Present (E) loop
10419 if Scope (E) = Scope (Prot_Typ)
10420 and then Comes_From_Source (E)
10421 and then Ekind (Subp) = Ekind (E)
10422 and then Present (First_Entity (E))
10423 and then Is_Controlling_Formal (First_Entity (E))
10424 and then Etype (First_Entity (E)) = Prot_Typ
10425 and then Subtype_Conformant (Subp, E,
10426 Skip_Controlling_Formals => True)
10428 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10435 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10438 end Matching_Original_Protected_Subprogram;
10440 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10443 -- Case 1: E is a subprogram whose first formal is a concurrent type
10444 -- defined in the scope of E that has an entry or subprogram whose
10445 -- profile matches E.
10447 if Comes_From_Source (E)
10448 and then Is_Subprogram (E)
10449 and then Present (First_Entity (E))
10450 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10453 Scope (Corresponding_Concurrent_Type
10454 (Etype (First_Entity (E))))
10457 (Matching_Entry_Or_Subprogram
10458 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10461 Report_Conflict (E,
10462 Matching_Entry_Or_Subprogram
10463 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10468 -- Case 2: E is an internally built dispatching subprogram of a
10469 -- protected type and there is a subprogram defined in the enclosing
10470 -- scope of the protected type that has the original name of E and
10471 -- its profile is conformant with the profile of E. We check the
10472 -- name of the original protected subprogram associated with E since
10473 -- the expander builds dispatching primitives of protected functions
10474 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10476 elsif not Comes_From_Source (E)
10477 and then Is_Subprogram (E)
10478 and then Present (First_Entity (E))
10479 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10480 and then Present (Original_Protected_Subprogram (E))
10483 (Matching_Original_Protected_Subprogram
10484 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10487 Report_Conflict (E,
10488 Matching_Original_Protected_Subprogram
10489 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10493 -- Case 3: E is an entry of a synchronized type and a matching
10494 -- procedure has been previously defined in the enclosing scope
10495 -- of the synchronized type.
10497 elsif Comes_From_Source (E)
10498 and then Ekind (E) = E_Entry
10500 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10502 Report_Conflict (E,
10503 Matching_Dispatching_Subprogram (Current_Scope, E));
10508 end Has_Matching_Entry_Or_Subprogram;
10510 ----------------------------
10511 -- Is_Private_Declaration --
10512 ----------------------------
10514 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10515 Decl : constant Node_Id := Unit_Declaration_Node (E);
10516 Priv_Decls : List_Id;
10519 if Is_Package_Or_Generic_Package (Current_Scope)
10520 and then In_Private_Part (Current_Scope)
10523 Private_Declarations (Package_Specification (Current_Scope));
10525 return In_Package_Body (Current_Scope)
10527 (Is_List_Member (Decl)
10528 and then List_Containing (Decl) = Priv_Decls)
10529 or else (Nkind (Parent (Decl)) = N_Package_Specification
10531 Is_Compilation_Unit
10532 (Defining_Entity (Parent (Decl)))
10533 and then List_Containing (Parent (Parent (Decl))) =
10538 end Is_Private_Declaration;
10540 --------------------------
10541 -- Is_Overriding_Alias --
10542 --------------------------
10544 function Is_Overriding_Alias
10545 (Old_E : Entity_Id;
10546 New_E : Entity_Id) return Boolean
10548 AO : constant Entity_Id := Alias (Old_E);
10549 AN : constant Entity_Id := Alias (New_E);
10552 return Scope (AO) /= Scope (AN)
10553 or else No (DTC_Entity (AO))
10554 or else No (DTC_Entity (AN))
10555 or else DT_Position (AO) = DT_Position (AN);
10556 end Is_Overriding_Alias;
10558 ---------------------
10559 -- Report_Conflict --
10560 ---------------------
10562 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10564 Error_Msg_Sloc := Sloc (E);
10566 -- Generate message, with useful additional warning if in generic
10568 if Is_Generic_Unit (E) then
10569 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10570 Error_Msg_N ("\& conflicts with declaration#", S);
10572 Error_Msg_N ("& conflicts with declaration#", S);
10574 end Report_Conflict;
10576 -- Start of processing for New_Overloaded_Entity
10579 -- We need to look for an entity that S may override. This must be a
10580 -- homonym in the current scope, so we look for the first homonym of
10581 -- S in the current scope as the starting point for the search.
10583 E := Current_Entity_In_Scope (S);
10585 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10586 -- They are directly added to the list of primitive operations of
10587 -- Derived_Type, unless this is a rederivation in the private part
10588 -- of an operation that was already derived in the visible part of
10589 -- the current package.
10591 if Ada_Version >= Ada_2005
10592 and then Present (Derived_Type)
10593 and then Present (Alias (S))
10594 and then Is_Dispatching_Operation (Alias (S))
10595 and then Present (Find_Dispatching_Type (Alias (S)))
10596 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10598 -- For private types, when the full-view is processed we propagate to
10599 -- the full view the non-overridden entities whose attribute "alias"
10600 -- references an interface primitive. These entities were added by
10601 -- Derive_Subprograms to ensure that interface primitives are
10604 -- Inside_Freeze_Actions is non zero when S corresponds with an
10605 -- internal entity that links an interface primitive with its
10606 -- covering primitive through attribute Interface_Alias (see
10607 -- Add_Internal_Interface_Entities).
10609 if Inside_Freezing_Actions = 0
10610 and then Is_Package_Or_Generic_Package (Current_Scope)
10611 and then In_Private_Part (Current_Scope)
10612 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10613 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10614 and then Full_View (Defining_Identifier (Parent (E)))
10615 = Defining_Identifier (Parent (S))
10616 and then Alias (E) = Alias (S)
10618 Check_Operation_From_Private_View (S, E);
10619 Set_Is_Dispatching_Operation (S);
10624 Enter_Overloaded_Entity (S);
10625 Check_Dispatching_Operation (S, Empty);
10626 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10632 -- For synchronized types check conflicts of this entity with previously
10633 -- defined entities.
10635 if Ada_Version >= Ada_2005
10636 and then Has_Matching_Entry_Or_Subprogram (S)
10641 -- If there is no homonym then this is definitely not overriding
10644 Enter_Overloaded_Entity (S);
10645 Check_Dispatching_Operation (S, Empty);
10646 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10648 -- If subprogram has an explicit declaration, check whether it has an
10649 -- overriding indicator.
10651 if Comes_From_Source (S) then
10652 Check_Synchronized_Overriding (S, Overridden_Subp);
10654 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10655 -- it may have overridden some hidden inherited primitive. Update
10656 -- Overridden_Subp to avoid spurious errors when checking the
10657 -- overriding indicator.
10659 if Ada_Version >= Ada_2012
10660 and then No (Overridden_Subp)
10661 and then Is_Dispatching_Operation (S)
10662 and then Present (Overridden_Operation (S))
10664 Overridden_Subp := Overridden_Operation (S);
10667 Check_Overriding_Indicator
10668 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10670 -- The Ghost policy in effect at the point of declaration of a
10671 -- parent subprogram and an overriding subprogram must match
10672 -- (SPARK RM 6.9(17)).
10674 Check_Ghost_Overriding (S, Overridden_Subp);
10677 -- If there is a homonym that is not overloadable, then we have an
10678 -- error, except for the special cases checked explicitly below.
10680 elsif not Is_Overloadable (E) then
10682 -- Check for spurious conflict produced by a subprogram that has the
10683 -- same name as that of the enclosing generic package. The conflict
10684 -- occurs within an instance, between the subprogram and the renaming
10685 -- declaration for the package. After the subprogram, the package
10686 -- renaming declaration becomes hidden.
10688 if Ekind (E) = E_Package
10689 and then Present (Renamed_Object (E))
10690 and then Renamed_Object (E) = Current_Scope
10691 and then Nkind (Parent (Renamed_Object (E))) =
10692 N_Package_Specification
10693 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10696 Set_Is_Immediately_Visible (E, False);
10697 Enter_Overloaded_Entity (S);
10698 Set_Homonym (S, Homonym (E));
10699 Check_Dispatching_Operation (S, Empty);
10700 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10702 -- If the subprogram is implicit it is hidden by the previous
10703 -- declaration. However if it is dispatching, it must appear in the
10704 -- dispatch table anyway, because it can be dispatched to even if it
10705 -- cannot be called directly.
10707 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10708 Set_Scope (S, Current_Scope);
10710 if Is_Dispatching_Operation (Alias (S)) then
10711 Check_Dispatching_Operation (S, Empty);
10717 Report_Conflict (S, E);
10721 -- E exists and is overloadable
10724 Check_Synchronized_Overriding (S, Overridden_Subp);
10726 -- Loop through E and its homonyms to determine if any of them is
10727 -- the candidate for overriding by S.
10729 while Present (E) loop
10731 -- Definitely not interesting if not in the current scope
10733 if Scope (E) /= Current_Scope then
10736 -- A function can overload the name of an abstract state. The
10737 -- state can be viewed as a function with a profile that cannot
10738 -- be matched by anything.
10740 elsif Ekind (S) = E_Function
10741 and then Ekind (E) = E_Abstract_State
10743 Enter_Overloaded_Entity (S);
10746 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10747 -- procedures locate the internally generated spec. We enforce
10748 -- mode conformance since a tagged type may inherit from
10749 -- interfaces several null primitives which differ only in
10750 -- the mode of the formals.
10752 elsif not Comes_From_Source (S)
10753 and then Is_Null_Procedure (S)
10754 and then not Mode_Conformant (E, S)
10758 -- Check if we have type conformance
10760 elsif Type_Conformant (E, S) then
10762 -- If the old and new entities have the same profile and one
10763 -- is not the body of the other, then this is an error, unless
10764 -- one of them is implicitly declared.
10766 -- There are some cases when both can be implicit, for example
10767 -- when both a literal and a function that overrides it are
10768 -- inherited in a derivation, or when an inherited operation
10769 -- of a tagged full type overrides the inherited operation of
10770 -- a private extension. Ada 83 had a special rule for the
10771 -- literal case. In Ada 95, the later implicit operation hides
10772 -- the former, and the literal is always the former. In the
10773 -- odd case where both are derived operations declared at the
10774 -- same point, both operations should be declared, and in that
10775 -- case we bypass the following test and proceed to the next
10776 -- part. This can only occur for certain obscure cases in
10777 -- instances, when an operation on a type derived from a formal
10778 -- private type does not override a homograph inherited from
10779 -- the actual. In subsequent derivations of such a type, the
10780 -- DT positions of these operations remain distinct, if they
10783 if Present (Alias (S))
10784 and then (No (Alias (E))
10785 or else Comes_From_Source (E)
10786 or else Is_Abstract_Subprogram (S)
10788 (Is_Dispatching_Operation (E)
10789 and then Is_Overriding_Alias (E, S)))
10790 and then Ekind (E) /= E_Enumeration_Literal
10792 -- When an derived operation is overloaded it may be due to
10793 -- the fact that the full view of a private extension
10794 -- re-inherits. It has to be dealt with.
10796 if Is_Package_Or_Generic_Package (Current_Scope)
10797 and then In_Private_Part (Current_Scope)
10799 Check_Operation_From_Private_View (S, E);
10802 -- In any case the implicit operation remains hidden by the
10803 -- existing declaration, which is overriding. Indicate that
10804 -- E overrides the operation from which S is inherited.
10806 if Present (Alias (S)) then
10807 Set_Overridden_Operation (E, Alias (S));
10808 Inherit_Subprogram_Contract (E, Alias (S));
10811 Set_Overridden_Operation (E, S);
10812 Inherit_Subprogram_Contract (E, S);
10815 if Comes_From_Source (E) then
10816 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10818 -- The Ghost policy in effect at the point of declaration
10819 -- of a parent subprogram and an overriding subprogram
10820 -- must match (SPARK RM 6.9(17)).
10822 Check_Ghost_Overriding (E, S);
10827 -- Within an instance, the renaming declarations for actual
10828 -- subprograms may become ambiguous, but they do not hide each
10831 elsif Ekind (E) /= E_Entry
10832 and then not Comes_From_Source (E)
10833 and then not Is_Generic_Instance (E)
10834 and then (Present (Alias (E))
10835 or else Is_Intrinsic_Subprogram (E))
10836 and then (not In_Instance
10837 or else No (Parent (E))
10838 or else Nkind (Unit_Declaration_Node (E)) /=
10839 N_Subprogram_Renaming_Declaration)
10841 -- A subprogram child unit is not allowed to override an
10842 -- inherited subprogram (10.1.1(20)).
10844 if Is_Child_Unit (S) then
10846 ("child unit overrides inherited subprogram in parent",
10851 if Is_Non_Overriding_Operation (E, S) then
10852 Enter_Overloaded_Entity (S);
10854 if No (Derived_Type)
10855 or else Is_Tagged_Type (Derived_Type)
10857 Check_Dispatching_Operation (S, Empty);
10863 -- E is a derived operation or an internal operator which
10864 -- is being overridden. Remove E from further visibility.
10865 -- Furthermore, if E is a dispatching operation, it must be
10866 -- replaced in the list of primitive operations of its type
10867 -- (see Override_Dispatching_Operation).
10869 Overridden_Subp := E;
10875 Prev := First_Entity (Current_Scope);
10876 while Present (Prev) and then Next_Entity (Prev) /= E loop
10877 Next_Entity (Prev);
10880 -- It is possible for E to be in the current scope and
10881 -- yet not in the entity chain. This can only occur in a
10882 -- generic context where E is an implicit concatenation
10883 -- in the formal part, because in a generic body the
10884 -- entity chain starts with the formals.
10886 -- In GNATprove mode, a wrapper for an operation with
10887 -- axiomatization may be a homonym of another declaration
10888 -- for an actual subprogram (needs refinement ???).
10892 and then GNATprove_Mode
10894 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10895 N_Subprogram_Renaming_Declaration
10899 pragma Assert (Chars (E) = Name_Op_Concat);
10904 -- E must be removed both from the entity_list of the
10905 -- current scope, and from the visibility chain.
10907 if Debug_Flag_E then
10908 Write_Str ("Override implicit operation ");
10909 Write_Int (Int (E));
10913 -- If E is a predefined concatenation, it stands for four
10914 -- different operations. As a result, a single explicit
10915 -- declaration does not hide it. In a possible ambiguous
10916 -- situation, Disambiguate chooses the user-defined op,
10917 -- so it is correct to retain the previous internal one.
10919 if Chars (E) /= Name_Op_Concat
10920 or else Ekind (E) /= E_Operator
10922 -- For nondispatching derived operations that are
10923 -- overridden by a subprogram declared in the private
10924 -- part of a package, we retain the derived subprogram
10925 -- but mark it as not immediately visible. If the
10926 -- derived operation was declared in the visible part
10927 -- then this ensures that it will still be visible
10928 -- outside the package with the proper signature
10929 -- (calls from outside must also be directed to this
10930 -- version rather than the overriding one, unlike the
10931 -- dispatching case). Calls from inside the package
10932 -- will still resolve to the overriding subprogram
10933 -- since the derived one is marked as not visible
10934 -- within the package.
10936 -- If the private operation is dispatching, we achieve
10937 -- the overriding by keeping the implicit operation
10938 -- but setting its alias to be the overriding one. In
10939 -- this fashion the proper body is executed in all
10940 -- cases, but the original signature is used outside
10943 -- If the overriding is not in the private part, we
10944 -- remove the implicit operation altogether.
10946 if Is_Private_Declaration (S) then
10947 if not Is_Dispatching_Operation (E) then
10948 Set_Is_Immediately_Visible (E, False);
10950 -- Work done in Override_Dispatching_Operation,
10951 -- so nothing else needs to be done here.
10957 -- Find predecessor of E in Homonym chain
10959 if E = Current_Entity (E) then
10962 Prev_Vis := Current_Entity (E);
10963 while Homonym (Prev_Vis) /= E loop
10964 Prev_Vis := Homonym (Prev_Vis);
10968 if Prev_Vis /= Empty then
10970 -- Skip E in the visibility chain
10972 Set_Homonym (Prev_Vis, Homonym (E));
10975 Set_Name_Entity_Id (Chars (E), Homonym (E));
10978 Set_Next_Entity (Prev, Next_Entity (E));
10980 if No (Next_Entity (Prev)) then
10981 Set_Last_Entity (Current_Scope, Prev);
10986 Enter_Overloaded_Entity (S);
10988 -- For entities generated by Derive_Subprograms the
10989 -- overridden operation is the inherited primitive
10990 -- (which is available through the attribute alias).
10992 if not (Comes_From_Source (E))
10993 and then Is_Dispatching_Operation (E)
10994 and then Find_Dispatching_Type (E) =
10995 Find_Dispatching_Type (S)
10996 and then Present (Alias (E))
10997 and then Comes_From_Source (Alias (E))
10999 Set_Overridden_Operation (S, Alias (E));
11000 Inherit_Subprogram_Contract (S, Alias (E));
11002 -- Normal case of setting entity as overridden
11004 -- Note: Static_Initialization and Overridden_Operation
11005 -- attributes use the same field in subprogram entities.
11006 -- Static_Initialization is only defined for internal
11007 -- initialization procedures, where Overridden_Operation
11008 -- is irrelevant. Therefore the setting of this attribute
11009 -- must check whether the target is an init_proc.
11011 elsif not Is_Init_Proc (S) then
11012 Set_Overridden_Operation (S, E);
11013 Inherit_Subprogram_Contract (S, E);
11016 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11018 -- The Ghost policy in effect at the point of declaration
11019 -- of a parent subprogram and an overriding subprogram
11020 -- must match (SPARK RM 6.9(17)).
11022 Check_Ghost_Overriding (S, E);
11024 -- If S is a user-defined subprogram or a null procedure
11025 -- expanded to override an inherited null procedure, or a
11026 -- predefined dispatching primitive then indicate that E
11027 -- overrides the operation from which S is inherited.
11029 if Comes_From_Source (S)
11031 (Present (Parent (S))
11033 Nkind (Parent (S)) = N_Procedure_Specification
11035 Null_Present (Parent (S)))
11037 (Present (Alias (E))
11039 Is_Predefined_Dispatching_Operation (Alias (E)))
11041 if Present (Alias (E)) then
11042 Set_Overridden_Operation (S, Alias (E));
11043 Inherit_Subprogram_Contract (S, Alias (E));
11047 if Is_Dispatching_Operation (E) then
11049 -- An overriding dispatching subprogram inherits the
11050 -- convention of the overridden subprogram (AI-117).
11052 Set_Convention (S, Convention (E));
11053 Check_Dispatching_Operation (S, E);
11056 Check_Dispatching_Operation (S, Empty);
11059 Check_For_Primitive_Subprogram
11060 (Is_Primitive_Subp, Is_Overriding => True);
11061 goto Check_Inequality;
11064 -- Apparent redeclarations in instances can occur when two
11065 -- formal types get the same actual type. The subprograms in
11066 -- in the instance are legal, even if not callable from the
11067 -- outside. Calls from within are disambiguated elsewhere.
11068 -- For dispatching operations in the visible part, the usual
11069 -- rules apply, and operations with the same profile are not
11070 -- legal (B830001).
11072 elsif (In_Instance_Visible_Part
11073 and then not Is_Dispatching_Operation (E))
11074 or else In_Instance_Not_Visible
11078 -- Here we have a real error (identical profile)
11081 Error_Msg_Sloc := Sloc (E);
11083 -- Avoid cascaded errors if the entity appears in
11084 -- subsequent calls.
11086 Set_Scope (S, Current_Scope);
11088 -- Generate error, with extra useful warning for the case
11089 -- of a generic instance with no completion.
11091 if Is_Generic_Instance (S)
11092 and then not Has_Completion (E)
11095 ("instantiation cannot provide body for&", S);
11096 Error_Msg_N ("\& conflicts with declaration#", S);
11098 Error_Msg_N ("& conflicts with declaration#", S);
11105 -- If one subprogram has an access parameter and the other
11106 -- a parameter of an access type, calls to either might be
11107 -- ambiguous. Verify that parameters match except for the
11108 -- access parameter.
11110 if May_Hide_Profile then
11116 F1 := First_Formal (S);
11117 F2 := First_Formal (E);
11118 while Present (F1) and then Present (F2) loop
11119 if Is_Access_Type (Etype (F1)) then
11120 if not Is_Access_Type (Etype (F2))
11121 or else not Conforming_Types
11122 (Designated_Type (Etype (F1)),
11123 Designated_Type (Etype (F2)),
11126 May_Hide_Profile := False;
11130 not Conforming_Types
11131 (Etype (F1), Etype (F2), Type_Conformant)
11133 May_Hide_Profile := False;
11140 if May_Hide_Profile
11144 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11153 -- On exit, we know that S is a new entity
11155 Enter_Overloaded_Entity (S);
11156 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11157 Check_Overriding_Indicator
11158 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11160 -- The Ghost policy in effect at the point of declaration of a parent
11161 -- subprogram and an overriding subprogram must match
11162 -- (SPARK RM 6.9(17)).
11164 Check_Ghost_Overriding (S, Overridden_Subp);
11166 -- Overloading is not allowed in SPARK, except for operators
11168 if Nkind (S) /= N_Defining_Operator_Symbol then
11169 Error_Msg_Sloc := Sloc (Homonym (S));
11170 Check_SPARK_05_Restriction
11171 ("overloading not allowed with entity#", S);
11174 -- If S is a derived operation for an untagged type then by
11175 -- definition it's not a dispatching operation (even if the parent
11176 -- operation was dispatching), so Check_Dispatching_Operation is not
11177 -- called in that case.
11179 if No (Derived_Type)
11180 or else Is_Tagged_Type (Derived_Type)
11182 Check_Dispatching_Operation (S, Empty);
11186 -- If this is a user-defined equality operator that is not a derived
11187 -- subprogram, create the corresponding inequality. If the operation is
11188 -- dispatching, the expansion is done elsewhere, and we do not create
11189 -- an explicit inequality operation.
11191 <<Check_Inequality>>
11192 if Chars (S) = Name_Op_Eq
11193 and then Etype (S) = Standard_Boolean
11194 and then Present (Parent (S))
11195 and then not Is_Dispatching_Operation (S)
11197 Make_Inequality_Operator (S);
11198 Check_Untagged_Equality (S);
11200 end New_Overloaded_Entity;
11202 ---------------------
11203 -- Process_Formals --
11204 ---------------------
11206 procedure Process_Formals
11208 Related_Nod : Node_Id)
11210 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11211 -- Determine whether an access type designates a type coming from a
11214 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11215 -- Check whether the default has a class-wide type. After analysis the
11216 -- default has the type of the formal, so we must also check explicitly
11217 -- for an access attribute.
11219 ----------------------------------
11220 -- Designates_From_Limited_With --
11221 ----------------------------------
11223 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11224 Desig : Entity_Id := Typ;
11227 if Is_Access_Type (Desig) then
11228 Desig := Directly_Designated_Type (Desig);
11231 if Is_Class_Wide_Type (Desig) then
11232 Desig := Root_Type (Desig);
11236 Ekind (Desig) = E_Incomplete_Type
11237 and then From_Limited_With (Desig);
11238 end Designates_From_Limited_With;
11240 ---------------------------
11241 -- Is_Class_Wide_Default --
11242 ---------------------------
11244 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11246 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11247 or else (Nkind (D) = N_Attribute_Reference
11248 and then Attribute_Name (D) = Name_Access
11249 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11250 end Is_Class_Wide_Default;
11254 Context : constant Node_Id := Parent (Parent (T));
11256 Formal : Entity_Id;
11257 Formal_Type : Entity_Id;
11258 Param_Spec : Node_Id;
11261 Num_Out_Params : Nat := 0;
11262 First_Out_Param : Entity_Id := Empty;
11263 -- Used for setting Is_Only_Out_Parameter
11265 -- Start of processing for Process_Formals
11268 -- In order to prevent premature use of the formals in the same formal
11269 -- part, the Ekind is left undefined until all default expressions are
11270 -- analyzed. The Ekind is established in a separate loop at the end.
11272 Param_Spec := First (T);
11273 while Present (Param_Spec) loop
11274 Formal := Defining_Identifier (Param_Spec);
11275 Set_Never_Set_In_Source (Formal, True);
11276 Enter_Name (Formal);
11278 -- Case of ordinary parameters
11280 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11281 Find_Type (Parameter_Type (Param_Spec));
11282 Ptype := Parameter_Type (Param_Spec);
11284 if Ptype = Error then
11288 Formal_Type := Entity (Ptype);
11290 if Is_Incomplete_Type (Formal_Type)
11292 (Is_Class_Wide_Type (Formal_Type)
11293 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11295 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11296 -- primitive operations, as long as their completion is
11297 -- in the same declarative part. If in the private part
11298 -- this means that the type cannot be a Taft-amendment type.
11299 -- Check is done on package exit. For access to subprograms,
11300 -- the use is legal for Taft-amendment types.
11302 -- Ada 2012: tagged incomplete types are allowed as generic
11303 -- formal types. They do not introduce dependencies and the
11304 -- corresponding generic subprogram does not have a delayed
11305 -- freeze, because it does not need a freeze node. However,
11306 -- it is still the case that untagged incomplete types cannot
11307 -- be Taft-amendment types and must be completed in private
11308 -- part, so the subprogram must appear in the list of private
11309 -- dependents of the type.
11311 if Is_Tagged_Type (Formal_Type)
11312 or else (Ada_Version >= Ada_2012
11313 and then not From_Limited_With (Formal_Type)
11314 and then not Is_Generic_Type (Formal_Type))
11316 if Ekind (Scope (Current_Scope)) = E_Package
11317 and then not Is_Generic_Type (Formal_Type)
11318 and then not Is_Class_Wide_Type (Formal_Type)
11321 (Parent (T), N_Access_Function_Definition,
11322 N_Access_Procedure_Definition)
11324 Append_Elmt (Current_Scope,
11325 Private_Dependents (Base_Type (Formal_Type)));
11327 -- Freezing is delayed to ensure that Register_Prim
11328 -- will get called for this operation, which is needed
11329 -- in cases where static dispatch tables aren't built.
11330 -- (Note that the same is done for controlling access
11331 -- parameter cases in function Access_Definition.)
11333 if not Is_Thunk (Current_Scope) then
11334 Set_Has_Delayed_Freeze (Current_Scope);
11339 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11340 N_Access_Procedure_Definition)
11342 -- AI05-0151: Tagged incomplete types are allowed in all
11343 -- formal parts. Untagged incomplete types are not allowed
11344 -- in bodies. Limited views of either kind are not allowed
11345 -- if there is no place at which the non-limited view can
11346 -- become available.
11348 -- Incomplete formal untagged types are not allowed in
11349 -- subprogram bodies (but are legal in their declarations).
11350 -- This excludes bodies created for null procedures, which
11351 -- are basic declarations.
11353 if Is_Generic_Type (Formal_Type)
11354 and then not Is_Tagged_Type (Formal_Type)
11355 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11358 ("invalid use of formal incomplete type", Param_Spec);
11360 elsif Ada_Version >= Ada_2012 then
11361 if Is_Tagged_Type (Formal_Type)
11362 and then (not From_Limited_With (Formal_Type)
11363 or else not In_Package_Body)
11367 elsif Nkind_In (Context, N_Accept_Statement,
11368 N_Accept_Alternative,
11370 or else (Nkind (Context) = N_Subprogram_Body
11371 and then Comes_From_Source (Context))
11374 ("invalid use of untagged incomplete type &",
11375 Ptype, Formal_Type);
11380 ("invalid use of incomplete type&",
11381 Param_Spec, Formal_Type);
11383 -- Further checks on the legality of incomplete types
11384 -- in formal parts are delayed until the freeze point
11385 -- of the enclosing subprogram or access to subprogram.
11389 elsif Ekind (Formal_Type) = E_Void then
11391 ("premature use of&",
11392 Parameter_Type (Param_Spec), Formal_Type);
11395 -- Ada 2012 (AI-142): Handle aliased parameters
11397 if Ada_Version >= Ada_2012
11398 and then Aliased_Present (Param_Spec)
11400 Set_Is_Aliased (Formal);
11403 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11404 -- declaration corresponding to the null-excluding type of the
11405 -- formal in the enclosing scope. Finally, replace the parameter
11406 -- type of the formal with the internal subtype.
11408 if Ada_Version >= Ada_2005
11409 and then Null_Exclusion_Present (Param_Spec)
11411 if not Is_Access_Type (Formal_Type) then
11413 ("`NOT NULL` allowed only for an access type", Param_Spec);
11416 if Can_Never_Be_Null (Formal_Type)
11417 and then Comes_From_Source (Related_Nod)
11420 ("`NOT NULL` not allowed (& already excludes null)",
11421 Param_Spec, Formal_Type);
11425 Create_Null_Excluding_Itype
11427 Related_Nod => Related_Nod,
11428 Scope_Id => Scope (Current_Scope));
11430 -- If the designated type of the itype is an itype that is
11431 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11432 -- on the access subtype, to prevent order-of-elaboration
11433 -- issues in the backend.
11436 -- type T is access procedure;
11437 -- procedure Op (O : not null T);
11439 if Is_Itype (Directly_Designated_Type (Formal_Type))
11441 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11443 Set_Has_Delayed_Freeze (Formal_Type);
11448 -- An access formal type
11452 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11454 -- No need to continue if we already notified errors
11456 if not Present (Formal_Type) then
11460 -- Ada 2005 (AI-254)
11463 AD : constant Node_Id :=
11464 Access_To_Subprogram_Definition
11465 (Parameter_Type (Param_Spec));
11467 if Present (AD) and then Protected_Present (AD) then
11469 Replace_Anonymous_Access_To_Protected_Subprogram
11475 Set_Etype (Formal, Formal_Type);
11477 -- Deal with default expression if present
11479 Default := Expression (Param_Spec);
11481 if Present (Default) then
11482 Check_SPARK_05_Restriction
11483 ("default expression is not allowed", Default);
11485 if Out_Present (Param_Spec) then
11487 ("default initialization only allowed for IN parameters",
11491 -- Do the special preanalysis of the expression (see section on
11492 -- "Handling of Default Expressions" in the spec of package Sem).
11494 Preanalyze_Spec_Expression (Default, Formal_Type);
11496 -- An access to constant cannot be the default for
11497 -- an access parameter that is an access to variable.
11499 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11500 and then not Is_Access_Constant (Formal_Type)
11501 and then Is_Access_Type (Etype (Default))
11502 and then Is_Access_Constant (Etype (Default))
11505 ("formal that is access to variable cannot be initialized "
11506 & "with an access-to-constant expression", Default);
11509 -- Check that the designated type of an access parameter's default
11510 -- is not a class-wide type unless the parameter's designated type
11511 -- is also class-wide.
11513 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11514 and then not Designates_From_Limited_With (Formal_Type)
11515 and then Is_Class_Wide_Default (Default)
11516 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11519 ("access to class-wide expression not allowed here", Default);
11522 -- Check incorrect use of dynamically tagged expressions
11524 if Is_Tagged_Type (Formal_Type) then
11525 Check_Dynamically_Tagged_Expression
11527 Typ => Formal_Type,
11528 Related_Nod => Default);
11532 -- Ada 2005 (AI-231): Static checks
11534 if Ada_Version >= Ada_2005
11535 and then Is_Access_Type (Etype (Formal))
11536 and then Can_Never_Be_Null (Etype (Formal))
11538 Null_Exclusion_Static_Checks (Param_Spec);
11541 -- The following checks are relevant only when SPARK_Mode is on as
11542 -- these are not standard Ada legality rules.
11544 if SPARK_Mode = On then
11545 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11547 -- A function cannot have a parameter of mode IN OUT or OUT
11550 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11552 ("function cannot have parameter of mode `OUT` or "
11553 & "`IN OUT`", Formal);
11556 -- A procedure cannot have an effectively volatile formal
11557 -- parameter of mode IN because it behaves as a constant
11558 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11560 elsif Ekind (Scope (Formal)) = E_Procedure
11561 and then Ekind (Formal) = E_In_Parameter
11562 and then Is_Effectively_Volatile (Formal)
11565 ("formal parameter of mode `IN` cannot be volatile", Formal);
11573 -- If this is the formal part of a function specification, analyze the
11574 -- subtype mark in the context where the formals are visible but not
11575 -- yet usable, and may hide outer homographs.
11577 if Nkind (Related_Nod) = N_Function_Specification then
11578 Analyze_Return_Type (Related_Nod);
11581 -- Now set the kind (mode) of each formal
11583 Param_Spec := First (T);
11584 while Present (Param_Spec) loop
11585 Formal := Defining_Identifier (Param_Spec);
11586 Set_Formal_Mode (Formal);
11588 if Ekind (Formal) = E_In_Parameter then
11589 Set_Default_Value (Formal, Expression (Param_Spec));
11591 if Present (Expression (Param_Spec)) then
11592 Default := Expression (Param_Spec);
11594 if Is_Scalar_Type (Etype (Default)) then
11595 if Nkind (Parameter_Type (Param_Spec)) /=
11596 N_Access_Definition
11598 Formal_Type := Entity (Parameter_Type (Param_Spec));
11602 (Related_Nod, Parameter_Type (Param_Spec));
11605 Apply_Scalar_Range_Check (Default, Formal_Type);
11609 elsif Ekind (Formal) = E_Out_Parameter then
11610 Num_Out_Params := Num_Out_Params + 1;
11612 if Num_Out_Params = 1 then
11613 First_Out_Param := Formal;
11616 elsif Ekind (Formal) = E_In_Out_Parameter then
11617 Num_Out_Params := Num_Out_Params + 1;
11620 -- Skip remaining processing if formal type was in error
11622 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11623 goto Next_Parameter;
11626 -- Force call by reference if aliased
11629 Conv : constant Convention_Id := Convention (Etype (Formal));
11631 if Is_Aliased (Formal) then
11632 Set_Mechanism (Formal, By_Reference);
11634 -- Warn if user asked this to be passed by copy
11636 if Conv = Convention_Ada_Pass_By_Copy then
11638 ("cannot pass aliased parameter & by copy??", Formal);
11641 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11643 elsif Conv = Convention_Ada_Pass_By_Copy then
11644 Set_Mechanism (Formal, By_Copy);
11646 elsif Conv = Convention_Ada_Pass_By_Reference then
11647 Set_Mechanism (Formal, By_Reference);
11655 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11656 Set_Is_Only_Out_Parameter (First_Out_Param);
11658 end Process_Formals;
11660 ----------------------------
11661 -- Reference_Body_Formals --
11662 ----------------------------
11664 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11669 if Error_Posted (Spec) then
11673 -- Iterate over both lists. They may be of different lengths if the two
11674 -- specs are not conformant.
11676 Fs := First_Formal (Spec);
11677 Fb := First_Formal (Bod);
11678 while Present (Fs) and then Present (Fb) loop
11679 Generate_Reference (Fs, Fb, 'b');
11681 if Style_Check then
11682 Style.Check_Identifier (Fb, Fs);
11685 Set_Spec_Entity (Fb, Fs);
11686 Set_Referenced (Fs, False);
11690 end Reference_Body_Formals;
11692 -------------------------
11693 -- Set_Actual_Subtypes --
11694 -------------------------
11696 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11698 Formal : Entity_Id;
11700 First_Stmt : Node_Id := Empty;
11701 AS_Needed : Boolean;
11704 -- If this is an empty initialization procedure, no need to create
11705 -- actual subtypes (small optimization).
11707 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11710 -- Within a predicate function we do not want to generate local
11711 -- subtypes that may generate nested predicate functions.
11713 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11717 -- The subtype declarations may freeze the formals. The body generated
11718 -- for an expression function is not a freeze point, so do not emit
11719 -- these declarations (small loss of efficiency in rare cases).
11721 if Nkind (N) = N_Subprogram_Body
11722 and then Was_Expression_Function (N)
11727 Formal := First_Formal (Subp);
11728 while Present (Formal) loop
11729 T := Etype (Formal);
11731 -- We never need an actual subtype for a constrained formal
11733 if Is_Constrained (T) then
11734 AS_Needed := False;
11736 -- If we have unknown discriminants, then we do not need an actual
11737 -- subtype, or more accurately we cannot figure it out. Note that
11738 -- all class-wide types have unknown discriminants.
11740 elsif Has_Unknown_Discriminants (T) then
11741 AS_Needed := False;
11743 -- At this stage we have an unconstrained type that may need an
11744 -- actual subtype. For sure the actual subtype is needed if we have
11745 -- an unconstrained array type. However, in an instance, the type
11746 -- may appear as a subtype of the full view, while the actual is
11747 -- in fact private (in which case no actual subtype is needed) so
11748 -- check the kind of the base type.
11750 elsif Is_Array_Type (Base_Type (T)) then
11753 -- The only other case needing an actual subtype is an unconstrained
11754 -- record type which is an IN parameter (we cannot generate actual
11755 -- subtypes for the OUT or IN OUT case, since an assignment can
11756 -- change the discriminant values. However we exclude the case of
11757 -- initialization procedures, since discriminants are handled very
11758 -- specially in this context, see the section entitled "Handling of
11759 -- Discriminants" in Einfo.
11761 -- We also exclude the case of Discrim_SO_Functions (functions used
11762 -- in front-end layout mode for size/offset values), since in such
11763 -- functions only discriminants are referenced, and not only are such
11764 -- subtypes not needed, but they cannot always be generated, because
11765 -- of order of elaboration issues.
11767 elsif Is_Record_Type (T)
11768 and then Ekind (Formal) = E_In_Parameter
11769 and then Chars (Formal) /= Name_uInit
11770 and then not Is_Unchecked_Union (T)
11771 and then not Is_Discrim_SO_Function (Subp)
11775 -- All other cases do not need an actual subtype
11778 AS_Needed := False;
11781 -- Generate actual subtypes for unconstrained arrays and
11782 -- unconstrained discriminated records.
11785 if Nkind (N) = N_Accept_Statement then
11787 -- If expansion is active, the formal is replaced by a local
11788 -- variable that renames the corresponding entry of the
11789 -- parameter block, and it is this local variable that may
11790 -- require an actual subtype.
11792 if Expander_Active then
11793 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11795 Decl := Build_Actual_Subtype (T, Formal);
11798 if Present (Handled_Statement_Sequence (N)) then
11800 First (Statements (Handled_Statement_Sequence (N)));
11801 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11802 Mark_Rewrite_Insertion (Decl);
11804 -- If the accept statement has no body, there will be no
11805 -- reference to the actuals, so no need to compute actual
11812 Decl := Build_Actual_Subtype (T, Formal);
11813 Prepend (Decl, Declarations (N));
11814 Mark_Rewrite_Insertion (Decl);
11817 -- The declaration uses the bounds of an existing object, and
11818 -- therefore needs no constraint checks.
11820 Analyze (Decl, Suppress => All_Checks);
11821 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11823 -- We need to freeze manually the generated type when it is
11824 -- inserted anywhere else than in a declarative part.
11826 if Present (First_Stmt) then
11827 Insert_List_Before_And_Analyze (First_Stmt,
11828 Freeze_Entity (Defining_Identifier (Decl), N));
11830 -- Ditto if the type has a dynamic predicate, because the
11831 -- generated function will mention the actual subtype. The
11832 -- predicate may come from an explicit aspect of be inherited.
11834 elsif Has_Predicates (T) then
11835 Insert_List_Before_And_Analyze (Decl,
11836 Freeze_Entity (Defining_Identifier (Decl), N));
11839 if Nkind (N) = N_Accept_Statement
11840 and then Expander_Active
11842 Set_Actual_Subtype (Renamed_Object (Formal),
11843 Defining_Identifier (Decl));
11845 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11849 Next_Formal (Formal);
11851 end Set_Actual_Subtypes;
11853 ---------------------
11854 -- Set_Formal_Mode --
11855 ---------------------
11857 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11858 Spec : constant Node_Id := Parent (Formal_Id);
11859 Id : constant Entity_Id := Scope (Formal_Id);
11862 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11863 -- since we ensure that corresponding actuals are always valid at the
11864 -- point of the call.
11866 if Out_Present (Spec) then
11867 if Ekind_In (Id, E_Entry, E_Entry_Family)
11868 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11870 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11873 if Ekind_In (Id, E_Function, E_Generic_Function) then
11875 -- [IN] OUT parameters allowed for functions in Ada 2012
11877 if Ada_Version >= Ada_2012 then
11879 -- Even in Ada 2012 operators can only have IN parameters
11881 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11882 Error_Msg_N ("operators can only have IN parameters", Spec);
11885 if In_Present (Spec) then
11886 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11888 Set_Ekind (Formal_Id, E_Out_Parameter);
11891 -- But not in earlier versions of Ada
11894 Error_Msg_N ("functions can only have IN parameters", Spec);
11895 Set_Ekind (Formal_Id, E_In_Parameter);
11898 elsif In_Present (Spec) then
11899 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11902 Set_Ekind (Formal_Id, E_Out_Parameter);
11903 Set_Never_Set_In_Source (Formal_Id, True);
11904 Set_Is_True_Constant (Formal_Id, False);
11905 Set_Current_Value (Formal_Id, Empty);
11909 Set_Ekind (Formal_Id, E_In_Parameter);
11912 -- Set Is_Known_Non_Null for access parameters since the language
11913 -- guarantees that access parameters are always non-null. We also set
11914 -- Can_Never_Be_Null, since there is no way to change the value.
11916 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11918 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11919 -- null; In Ada 2005, only if then null_exclusion is explicit.
11921 if Ada_Version < Ada_2005
11922 or else Can_Never_Be_Null (Etype (Formal_Id))
11924 Set_Is_Known_Non_Null (Formal_Id);
11925 Set_Can_Never_Be_Null (Formal_Id);
11928 -- Ada 2005 (AI-231): Null-exclusion access subtype
11930 elsif Is_Access_Type (Etype (Formal_Id))
11931 and then Can_Never_Be_Null (Etype (Formal_Id))
11933 Set_Is_Known_Non_Null (Formal_Id);
11935 -- We can also set Can_Never_Be_Null (thus preventing some junk
11936 -- access checks) for the case of an IN parameter, which cannot
11937 -- be changed, or for an IN OUT parameter, which can be changed but
11938 -- not to a null value. But for an OUT parameter, the initial value
11939 -- passed in can be null, so we can't set this flag in that case.
11941 if Ekind (Formal_Id) /= E_Out_Parameter then
11942 Set_Can_Never_Be_Null (Formal_Id);
11946 Set_Mechanism (Formal_Id, Default_Mechanism);
11947 Set_Formal_Validity (Formal_Id);
11948 end Set_Formal_Mode;
11950 -------------------------
11951 -- Set_Formal_Validity --
11952 -------------------------
11954 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11956 -- If no validity checking, then we cannot assume anything about the
11957 -- validity of parameters, since we do not know there is any checking
11958 -- of the validity on the call side.
11960 if not Validity_Checks_On then
11963 -- If validity checking for parameters is enabled, this means we are
11964 -- not supposed to make any assumptions about argument values.
11966 elsif Validity_Check_Parameters then
11969 -- If we are checking in parameters, we will assume that the caller is
11970 -- also checking parameters, so we can assume the parameter is valid.
11972 elsif Ekind (Formal_Id) = E_In_Parameter
11973 and then Validity_Check_In_Params
11975 Set_Is_Known_Valid (Formal_Id, True);
11977 -- Similar treatment for IN OUT parameters
11979 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11980 and then Validity_Check_In_Out_Params
11982 Set_Is_Known_Valid (Formal_Id, True);
11984 end Set_Formal_Validity;
11986 ------------------------
11987 -- Subtype_Conformant --
11988 ------------------------
11990 function Subtype_Conformant
11991 (New_Id : Entity_Id;
11992 Old_Id : Entity_Id;
11993 Skip_Controlling_Formals : Boolean := False) return Boolean
11997 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
11998 Skip_Controlling_Formals => Skip_Controlling_Formals);
12000 end Subtype_Conformant;
12002 ---------------------
12003 -- Type_Conformant --
12004 ---------------------
12006 function Type_Conformant
12007 (New_Id : Entity_Id;
12008 Old_Id : Entity_Id;
12009 Skip_Controlling_Formals : Boolean := False) return Boolean
12013 May_Hide_Profile := False;
12015 (New_Id, Old_Id, Type_Conformant, False, Result,
12016 Skip_Controlling_Formals => Skip_Controlling_Formals);
12018 end Type_Conformant;
12020 -------------------------------
12021 -- Valid_Operator_Definition --
12022 -------------------------------
12024 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12027 Id : constant Name_Id := Chars (Designator);
12031 F := First_Formal (Designator);
12032 while Present (F) loop
12035 if Present (Default_Value (F)) then
12037 ("default values not allowed for operator parameters",
12040 -- For function instantiations that are operators, we must check
12041 -- separately that the corresponding generic only has in-parameters.
12042 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12043 -- an error could not arise in earlier versions of the language.
12045 elsif Ekind (F) /= E_In_Parameter then
12046 Error_Msg_N ("operators can only have IN parameters", F);
12052 -- Verify that user-defined operators have proper number of arguments
12053 -- First case of operators which can only be unary
12055 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12058 -- Case of operators which can be unary or binary
12060 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12061 N_OK := (N in 1 .. 2);
12063 -- All other operators can only be binary
12071 ("incorrect number of arguments for operator", Designator);
12075 and then Base_Type (Etype (Designator)) = Standard_Boolean
12076 and then not Is_Intrinsic_Subprogram (Designator)
12079 ("explicit definition of inequality not allowed", Designator);
12081 end Valid_Operator_Definition;