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 ---------------------
1042 Obj_Decl : Node_Id := Empty;
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
1193 if Present (Expr) then
1195 -- Defend against previous errors
1197 if Nkind (Expr) = N_Empty
1198 or else No (Etype (Expr))
1203 -- Apply constraint check. Note that this is done before the implicit
1204 -- conversion of the expression done for anonymous access types to
1205 -- ensure correct generation of the null-excluding check associated
1206 -- with null-excluding expressions found in return statements.
1208 Apply_Constraint_Check (Expr, R_Type);
1210 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1211 -- type, apply an implicit conversion of the expression to that type
1212 -- to force appropriate static and run-time accessibility checks.
1214 if Ada_Version >= Ada_2005
1215 and then Ekind (R_Type) = E_Anonymous_Access_Type
1217 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1218 Analyze_And_Resolve (Expr, R_Type);
1220 -- If this is a local anonymous access to subprogram, the
1221 -- accessibility check can be applied statically. The return is
1222 -- illegal if the access type of the return expression is declared
1223 -- inside of the subprogram (except if it is the subtype indication
1224 -- of an extended return statement).
1226 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1227 if not Comes_From_Source (Current_Scope)
1228 or else Ekind (Current_Scope) = E_Return_Statement
1233 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1235 Error_Msg_N ("cannot return local access to subprogram", N);
1238 -- The expression cannot be of a formal incomplete type
1240 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1241 and then Is_Generic_Type (Etype (Expr))
1244 ("cannot return expression of a formal incomplete type", N);
1247 -- If the result type is class-wide, then check that the return
1248 -- expression's type is not declared at a deeper level than the
1249 -- function (RM05-6.5(5.6/2)).
1251 if Ada_Version >= Ada_2005
1252 and then Is_Class_Wide_Type (R_Type)
1254 if Type_Access_Level (Etype (Expr)) >
1255 Subprogram_Access_Level (Scope_Id)
1258 ("level of return expression type is deeper than "
1259 & "class-wide function!", Expr);
1263 -- Check incorrect use of dynamically tagged expression
1265 if Is_Tagged_Type (R_Type) then
1266 Check_Dynamically_Tagged_Expression
1272 -- ??? A real run-time accessibility check is needed in cases
1273 -- involving dereferences of access parameters. For now we just
1274 -- check the static cases.
1276 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1277 and then Is_Limited_View (Etype (Scope_Id))
1278 and then Object_Access_Level (Expr) >
1279 Subprogram_Access_Level (Scope_Id)
1281 -- Suppress the message in a generic, where the rewriting
1284 if Inside_A_Generic then
1289 Make_Raise_Program_Error (Loc,
1290 Reason => PE_Accessibility_Check_Failed));
1293 Error_Msg_Warn := SPARK_Mode /= On;
1294 Error_Msg_N ("cannot return a local value by reference<<", N);
1295 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1299 if Known_Null (Expr)
1300 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1301 and then Null_Exclusion_Present (Parent (Scope_Id))
1303 Apply_Compile_Time_Constraint_Error
1305 Msg => "(Ada 2005) null not allowed for "
1306 & "null-excluding return??",
1307 Reason => CE_Null_Not_Allowed);
1310 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1311 -- has no initializing expression.
1313 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1314 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1315 Subprogram_Access_Level (Scope_Id)
1318 ("level of return expression type is deeper than "
1319 & "class-wide function!", Obj_Decl);
1322 end Analyze_Function_Return;
1324 -------------------------------------
1325 -- Analyze_Generic_Subprogram_Body --
1326 -------------------------------------
1328 procedure Analyze_Generic_Subprogram_Body
1332 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1333 Kind : constant Entity_Kind := Ekind (Gen_Id);
1334 Body_Id : Entity_Id;
1339 -- Copy body and disable expansion while analyzing the generic For a
1340 -- stub, do not copy the stub (which would load the proper body), this
1341 -- will be done when the proper body is analyzed.
1343 if Nkind (N) /= N_Subprogram_Body_Stub then
1344 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1347 -- Once the contents of the generic copy and the template are
1348 -- swapped, do the same for their respective aspect specifications.
1350 Exchange_Aspects (N, New_N);
1352 -- Collect all contract-related source pragmas found within the
1353 -- template and attach them to the contract of the subprogram body.
1354 -- This contract is used in the capture of global references within
1357 Create_Generic_Contract (N);
1362 Spec := Specification (N);
1364 -- Within the body of the generic, the subprogram is callable, and
1365 -- behaves like the corresponding non-generic unit.
1367 Body_Id := Defining_Entity (Spec);
1369 if Kind = E_Generic_Procedure
1370 and then Nkind (Spec) /= N_Procedure_Specification
1372 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1375 elsif Kind = E_Generic_Function
1376 and then Nkind (Spec) /= N_Function_Specification
1378 Error_Msg_N ("invalid body for generic function ", Body_Id);
1382 Set_Corresponding_Body (Gen_Decl, Body_Id);
1384 if Has_Completion (Gen_Id)
1385 and then Nkind (Parent (N)) /= N_Subunit
1387 Error_Msg_N ("duplicate generic body", N);
1390 Set_Has_Completion (Gen_Id);
1393 if Nkind (N) = N_Subprogram_Body_Stub then
1394 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1396 Set_Corresponding_Spec (N, Gen_Id);
1399 if Nkind (Parent (N)) = N_Compilation_Unit then
1400 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1403 -- Make generic parameters immediately visible in the body. They are
1404 -- needed to process the formals declarations. Then make the formals
1405 -- visible in a separate step.
1407 Push_Scope (Gen_Id);
1411 First_Ent : Entity_Id;
1414 First_Ent := First_Entity (Gen_Id);
1417 while Present (E) and then not Is_Formal (E) loop
1422 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1424 -- Now generic formals are visible, and the specification can be
1425 -- analyzed, for subsequent conformance check.
1427 Body_Id := Analyze_Subprogram_Specification (Spec);
1429 -- Make formal parameters visible
1433 -- E is the first formal parameter, we loop through the formals
1434 -- installing them so that they will be visible.
1436 Set_First_Entity (Gen_Id, E);
1437 while Present (E) loop
1443 -- Visible generic entity is callable within its own body
1445 Set_Ekind (Gen_Id, Ekind (Body_Id));
1446 Set_Ekind (Body_Id, E_Subprogram_Body);
1447 Set_Convention (Body_Id, Convention (Gen_Id));
1448 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1449 Set_Scope (Body_Id, Scope (Gen_Id));
1451 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1453 if Nkind (N) = N_Subprogram_Body_Stub then
1455 -- No body to analyze, so restore state of generic unit
1457 Set_Ekind (Gen_Id, Kind);
1458 Set_Ekind (Body_Id, Kind);
1460 if Present (First_Ent) then
1461 Set_First_Entity (Gen_Id, First_Ent);
1468 -- If this is a compilation unit, it must be made visible explicitly,
1469 -- because the compilation of the declaration, unlike other library
1470 -- unit declarations, does not. If it is not a unit, the following
1471 -- is redundant but harmless.
1473 Set_Is_Immediately_Visible (Gen_Id);
1474 Reference_Body_Formals (Gen_Id, Body_Id);
1476 if Is_Child_Unit (Gen_Id) then
1477 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1480 Set_Actual_Subtypes (N, Current_Scope);
1482 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1483 Set_SPARK_Pragma_Inherited (Body_Id);
1485 -- Analyze any aspect specifications that appear on the generic
1488 if Has_Aspects (N) then
1489 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
1492 Analyze_Declarations (Declarations (N));
1495 -- Process the contract of the subprogram body after all declarations
1496 -- have been analyzed. This ensures that any contract-related pragmas
1497 -- are available through the N_Contract node of the body.
1499 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1501 Analyze (Handled_Statement_Sequence (N));
1502 Save_Global_References (Original_Node (N));
1504 -- Prior to exiting the scope, include generic formals again (if any
1505 -- are present) in the set of local entities.
1507 if Present (First_Ent) then
1508 Set_First_Entity (Gen_Id, First_Ent);
1511 Check_References (Gen_Id);
1514 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1515 Update_Use_Clause_Chain;
1516 Validate_Categorization_Dependency (N, Gen_Id);
1518 Check_Subprogram_Order (N);
1520 -- Outside of its body, unit is generic again
1522 Set_Ekind (Gen_Id, Kind);
1523 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1526 Style.Check_Identifier (Body_Id, Gen_Id);
1530 end Analyze_Generic_Subprogram_Body;
1532 ----------------------------
1533 -- Analyze_Null_Procedure --
1534 ----------------------------
1536 procedure Analyze_Null_Procedure
1538 Is_Completion : out Boolean)
1540 Loc : constant Source_Ptr := Sloc (N);
1541 Spec : constant Node_Id := Specification (N);
1542 Designator : Entity_Id;
1544 Null_Body : Node_Id := Empty;
1545 Null_Stmt : Node_Id := Null_Statement (Spec);
1549 -- Capture the profile of the null procedure before analysis, for
1550 -- expansion at the freeze point and at each point of call. The body is
1551 -- used if the procedure has preconditions, or if it is a completion. In
1552 -- the first case the body is analyzed at the freeze point, in the other
1553 -- it replaces the null procedure declaration.
1555 -- For a null procedure that comes from source, a NULL statement is
1556 -- provided by the parser, which carries the source location of the
1557 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1558 -- from expansion, create one now.
1560 if No (Null_Stmt) then
1561 Null_Stmt := Make_Null_Statement (Loc);
1565 Make_Subprogram_Body (Loc,
1566 Specification => New_Copy_Tree (Spec),
1567 Declarations => New_List,
1568 Handled_Statement_Sequence =>
1569 Make_Handled_Sequence_Of_Statements (Loc,
1570 Statements => New_List (Null_Stmt)));
1572 -- Create new entities for body and formals
1574 Set_Defining_Unit_Name (Specification (Null_Body),
1575 Make_Defining_Identifier
1576 (Sloc (Defining_Entity (N)),
1577 Chars (Defining_Entity (N))));
1579 Form := First (Parameter_Specifications (Specification (Null_Body)));
1580 while Present (Form) loop
1581 Set_Defining_Identifier (Form,
1582 Make_Defining_Identifier
1583 (Sloc (Defining_Identifier (Form)),
1584 Chars (Defining_Identifier (Form))));
1588 -- Determine whether the null procedure may be a completion of a generic
1589 -- suprogram, in which case we use the new null body as the completion
1590 -- and set minimal semantic information on the original declaration,
1591 -- which is rewritten as a null statement.
1593 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1595 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1596 Insert_Before (N, Null_Body);
1597 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1599 Rewrite (N, Make_Null_Statement (Loc));
1600 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1601 Is_Completion := True;
1605 -- Resolve the types of the formals now, because the freeze point may
1606 -- appear in a different context, e.g. an instantiation.
1608 Form := First (Parameter_Specifications (Specification (Null_Body)));
1609 while Present (Form) loop
1610 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1611 Find_Type (Parameter_Type (Form));
1613 elsif No (Access_To_Subprogram_Definition
1614 (Parameter_Type (Form)))
1616 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1618 -- The case of a null procedure with a formal that is an
1619 -- access-to-subprogram type, and that is used as an actual
1620 -- in an instantiation is left to the enthusiastic reader.
1630 -- If there are previous overloadable entities with the same name, check
1631 -- whether any of them is completed by the null procedure.
1633 if Present (Prev) and then Is_Overloadable (Prev) then
1634 Designator := Analyze_Subprogram_Specification (Spec);
1635 Prev := Find_Corresponding_Spec (N);
1638 if No (Prev) or else not Comes_From_Source (Prev) then
1639 Designator := Analyze_Subprogram_Specification (Spec);
1640 Set_Has_Completion (Designator);
1642 -- Signal to caller that this is a procedure declaration
1644 Is_Completion := False;
1646 -- Null procedures are always inlined, but generic formal subprograms
1647 -- which appear as such in the internal instance of formal packages,
1648 -- need no completion and are not marked Inline.
1651 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1653 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1654 Set_Body_To_Inline (N, Null_Body);
1655 Set_Is_Inlined (Designator);
1659 -- The null procedure is a completion. We unconditionally rewrite
1660 -- this as a null body (even if expansion is not active), because
1661 -- there are various error checks that are applied on this body
1662 -- when it is analyzed (e.g. correct aspect placement).
1664 if Has_Completion (Prev) then
1665 Error_Msg_Sloc := Sloc (Prev);
1666 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1669 Check_Previous_Null_Procedure (N, Prev);
1671 Is_Completion := True;
1672 Rewrite (N, Null_Body);
1675 end Analyze_Null_Procedure;
1677 -----------------------------
1678 -- Analyze_Operator_Symbol --
1679 -----------------------------
1681 -- An operator symbol such as "+" or "and" may appear in context where the
1682 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1683 -- is just a string, as in (conjunction = "or"). In these cases the parser
1684 -- generates this node, and the semantics does the disambiguation. Other
1685 -- such case are actuals in an instantiation, the generic unit in an
1686 -- instantiation, and pragma arguments.
1688 procedure Analyze_Operator_Symbol (N : Node_Id) is
1689 Par : constant Node_Id := Parent (N);
1692 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1693 or else Nkind (Par) = N_Function_Instantiation
1694 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1695 or else (Nkind (Par) = N_Pragma_Argument_Association
1696 and then not Is_Pragma_String_Literal (Par))
1697 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1698 or else (Nkind (Par) = N_Attribute_Reference
1699 and then Attribute_Name (Par) /= Name_Value)
1701 Find_Direct_Name (N);
1704 Change_Operator_Symbol_To_String_Literal (N);
1707 end Analyze_Operator_Symbol;
1709 -----------------------------------
1710 -- Analyze_Parameter_Association --
1711 -----------------------------------
1713 procedure Analyze_Parameter_Association (N : Node_Id) is
1715 Analyze (Explicit_Actual_Parameter (N));
1716 end Analyze_Parameter_Association;
1718 ----------------------------
1719 -- Analyze_Procedure_Call --
1720 ----------------------------
1722 -- WARNING: This routine manages Ghost regions. Return statements must be
1723 -- replaced by gotos which jump to the end of the routine and restore the
1726 procedure Analyze_Procedure_Call (N : Node_Id) is
1727 procedure Analyze_Call_And_Resolve;
1728 -- Do Analyze and Resolve calls for procedure call. At the end, check
1729 -- for illegal order dependence.
1730 -- ??? where is the check for illegal order dependencies?
1732 ------------------------------
1733 -- Analyze_Call_And_Resolve --
1734 ------------------------------
1736 procedure Analyze_Call_And_Resolve is
1738 if Nkind (N) = N_Procedure_Call_Statement then
1740 Resolve (N, Standard_Void_Type);
1744 end Analyze_Call_And_Resolve;
1748 Actuals : constant List_Id := Parameter_Associations (N);
1749 Loc : constant Source_Ptr := Sloc (N);
1750 P : constant Node_Id := Name (N);
1752 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1753 -- Save the Ghost mode to restore on exit
1758 -- Start of processing for Analyze_Procedure_Call
1761 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1762 -- a procedure call or an entry call. The prefix may denote an access
1763 -- to subprogram type, in which case an implicit dereference applies.
1764 -- If the prefix is an indexed component (without implicit dereference)
1765 -- then the construct denotes a call to a member of an entire family.
1766 -- If the prefix is a simple name, it may still denote a call to a
1767 -- parameterless member of an entry family. Resolution of these various
1768 -- interpretations is delicate.
1770 -- Do not analyze machine code statements to avoid rejecting them in
1773 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1774 Set_Etype (P, Standard_Void_Type);
1779 -- If this is a call of the form Obj.Op, the call may have been analyzed
1780 -- and possibly rewritten into a block, in which case we are done.
1782 if Analyzed (N) then
1785 -- If there is an error analyzing the name (which may have been
1786 -- rewritten if the original call was in prefix notation) then error
1787 -- has been emitted already, mark node and return.
1789 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1790 Set_Etype (N, Any_Type);
1794 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1795 -- Set the mode now to ensure that any nodes generated during analysis
1796 -- and expansion are properly marked as Ghost.
1798 Mark_And_Set_Ghost_Procedure_Call (N);
1800 -- Otherwise analyze the parameters
1802 if Present (Actuals) then
1803 Actual := First (Actuals);
1805 while Present (Actual) loop
1807 Check_Parameterless_Call (Actual);
1812 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1814 if Nkind (P) = N_Attribute_Reference
1815 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1817 Name_Elab_Subp_Body)
1819 if Present (Actuals) then
1821 ("no parameters allowed for this call", First (Actuals));
1825 Set_Etype (N, Standard_Void_Type);
1828 elsif Is_Entity_Name (P)
1829 and then Is_Record_Type (Etype (Entity (P)))
1830 and then Remote_AST_I_Dereference (P)
1834 elsif Is_Entity_Name (P)
1835 and then Ekind (Entity (P)) /= E_Entry_Family
1837 if Is_Access_Type (Etype (P))
1838 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1839 and then No (Actuals)
1840 and then Comes_From_Source (N)
1842 Error_Msg_N ("missing explicit dereference in call", N);
1845 Analyze_Call_And_Resolve;
1847 -- If the prefix is the simple name of an entry family, this is a
1848 -- parameterless call from within the task body itself.
1850 elsif Is_Entity_Name (P)
1851 and then Nkind (P) = N_Identifier
1852 and then Ekind (Entity (P)) = E_Entry_Family
1853 and then Present (Actuals)
1854 and then No (Next (First (Actuals)))
1856 -- Can be call to parameterless entry family. What appears to be the
1857 -- sole argument is in fact the entry index. Rewrite prefix of node
1858 -- accordingly. Source representation is unchanged by this
1862 Make_Indexed_Component (Loc,
1864 Make_Selected_Component (Loc,
1865 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1866 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1867 Expressions => Actuals);
1868 Set_Name (N, New_N);
1869 Set_Etype (New_N, Standard_Void_Type);
1870 Set_Parameter_Associations (N, No_List);
1871 Analyze_Call_And_Resolve;
1873 elsif Nkind (P) = N_Explicit_Dereference then
1874 if Ekind (Etype (P)) = E_Subprogram_Type then
1875 Analyze_Call_And_Resolve;
1877 Error_Msg_N ("expect access to procedure in call", P);
1880 -- The name can be a selected component or an indexed component that
1881 -- yields an access to subprogram. Such a prefix is legal if the call
1882 -- has parameter associations.
1884 elsif Is_Access_Type (Etype (P))
1885 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1887 if Present (Actuals) then
1888 Analyze_Call_And_Resolve;
1890 Error_Msg_N ("missing explicit dereference in call ", N);
1893 -- If not an access to subprogram, then the prefix must resolve to the
1894 -- name of an entry, entry family, or protected operation.
1896 -- For the case of a simple entry call, P is a selected component where
1897 -- the prefix is the task and the selector name is the entry. A call to
1898 -- a protected procedure will have the same syntax. If the protected
1899 -- object contains overloaded operations, the entity may appear as a
1900 -- function, the context will select the operation whose type is Void.
1902 elsif Nkind (P) = N_Selected_Component
1903 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1907 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1908 -- in prefix notation may still be missing its controlling argument,
1909 -- so perform the transformation now.
1911 if SPARK_Mode = On and then In_Inlined_Body then
1913 Subp : constant Entity_Id := Entity (Selector_Name (P));
1914 Typ : constant Entity_Id := Etype (Prefix (P));
1917 if Is_Tagged_Type (Typ)
1918 and then Present (First_Formal (Subp))
1919 and then Etype (First_Formal (Subp)) = Typ
1920 and then Try_Object_Operation (P)
1925 Analyze_Call_And_Resolve;
1930 Analyze_Call_And_Resolve;
1933 elsif Nkind (P) = N_Selected_Component
1934 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1935 and then Present (Actuals)
1936 and then No (Next (First (Actuals)))
1938 -- Can be call to parameterless entry family. What appears to be the
1939 -- sole argument is in fact the entry index. Rewrite prefix of node
1940 -- accordingly. Source representation is unchanged by this
1944 Make_Indexed_Component (Loc,
1945 Prefix => New_Copy (P),
1946 Expressions => Actuals);
1947 Set_Name (N, New_N);
1948 Set_Etype (New_N, Standard_Void_Type);
1949 Set_Parameter_Associations (N, No_List);
1950 Analyze_Call_And_Resolve;
1952 -- For the case of a reference to an element of an entry family, P is
1953 -- an indexed component whose prefix is a selected component (task and
1954 -- entry family), and whose index is the entry family index.
1956 elsif Nkind (P) = N_Indexed_Component
1957 and then Nkind (Prefix (P)) = N_Selected_Component
1958 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1960 Analyze_Call_And_Resolve;
1962 -- If the prefix is the name of an entry family, it is a call from
1963 -- within the task body itself.
1965 elsif Nkind (P) = N_Indexed_Component
1966 and then Nkind (Prefix (P)) = N_Identifier
1967 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1970 Make_Selected_Component (Loc,
1972 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1973 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1974 Rewrite (Prefix (P), New_N);
1976 Analyze_Call_And_Resolve;
1978 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1979 -- procedure name, so the construct can only be a qualified expression.
1981 elsif Nkind (P) = N_Qualified_Expression
1982 and then Ada_Version >= Ada_2012
1984 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1987 -- Anything else is an error
1990 Error_Msg_N ("invalid procedure or entry call", N);
1994 Restore_Ghost_Mode (Saved_GM);
1995 end Analyze_Procedure_Call;
1997 ------------------------------
1998 -- Analyze_Return_Statement --
1999 ------------------------------
2001 procedure Analyze_Return_Statement (N : Node_Id) is
2002 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2003 N_Simple_Return_Statement));
2005 Returns_Object : constant Boolean :=
2006 Nkind (N) = N_Extended_Return_Statement
2008 (Nkind (N) = N_Simple_Return_Statement
2009 and then Present (Expression (N)));
2010 -- True if we're returning something; that is, "return <expression>;"
2011 -- or "return Result : T [:= ...]". False for "return;". Used for error
2012 -- checking: If Returns_Object is True, N should apply to a function
2013 -- body; otherwise N should apply to a procedure body, entry body,
2014 -- accept statement, or extended return statement.
2016 function Find_What_It_Applies_To return Entity_Id;
2017 -- Find the entity representing the innermost enclosing body, accept
2018 -- statement, or extended return statement. If the result is a callable
2019 -- construct or extended return statement, then this will be the value
2020 -- of the Return_Applies_To attribute. Otherwise, the program is
2021 -- illegal. See RM-6.5(4/2).
2023 -----------------------------
2024 -- Find_What_It_Applies_To --
2025 -----------------------------
2027 function Find_What_It_Applies_To return Entity_Id is
2028 Result : Entity_Id := Empty;
2031 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2032 -- and postconditions.
2034 for J in reverse 0 .. Scope_Stack.Last loop
2035 Result := Scope_Stack.Table (J).Entity;
2036 exit when not Ekind_In (Result, E_Block, E_Loop)
2037 and then Chars (Result) /= Name_uPostconditions;
2040 pragma Assert (Present (Result));
2042 end Find_What_It_Applies_To;
2044 -- Local declarations
2046 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2047 Kind : constant Entity_Kind := Ekind (Scope_Id);
2048 Loc : constant Source_Ptr := Sloc (N);
2049 Stm_Entity : constant Entity_Id :=
2051 (E_Return_Statement, Current_Scope, Loc, 'R');
2053 -- Start of processing for Analyze_Return_Statement
2056 Set_Return_Statement_Entity (N, Stm_Entity);
2058 Set_Etype (Stm_Entity, Standard_Void_Type);
2059 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2061 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2062 -- (4/2): an inner return statement will apply to this extended return.
2064 if Nkind (N) = N_Extended_Return_Statement then
2065 Push_Scope (Stm_Entity);
2068 -- Check that pragma No_Return is obeyed. Don't complain about the
2069 -- implicitly-generated return that is placed at the end.
2071 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2072 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2075 -- Warn on any unassigned OUT parameters if in procedure
2077 if Ekind (Scope_Id) = E_Procedure then
2078 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2081 -- Check that functions return objects, and other things do not
2083 if Kind = E_Function or else Kind = E_Generic_Function then
2084 if not Returns_Object then
2085 Error_Msg_N ("missing expression in return from function", N);
2088 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2089 if Returns_Object then
2090 Error_Msg_N ("procedure cannot return value (use function)", N);
2093 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2094 if Returns_Object then
2095 if Is_Protected_Type (Scope (Scope_Id)) then
2096 Error_Msg_N ("entry body cannot return value", N);
2098 Error_Msg_N ("accept statement cannot return value", N);
2102 elsif Kind = E_Return_Statement then
2104 -- We are nested within another return statement, which must be an
2105 -- extended_return_statement.
2107 if Returns_Object then
2108 if Nkind (N) = N_Extended_Return_Statement then
2110 ("extended return statement cannot be nested (use `RETURN;`)",
2113 -- Case of a simple return statement with a value inside extended
2114 -- return statement.
2118 ("return nested in extended return statement cannot return "
2119 & "value (use `RETURN;`)", N);
2124 Error_Msg_N ("illegal context for return statement", N);
2127 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2128 Analyze_Function_Return (N);
2130 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2131 Set_Return_Present (Scope_Id);
2134 if Nkind (N) = N_Extended_Return_Statement then
2138 Kill_Current_Values (Last_Assignment_Only => True);
2139 Check_Unreachable_Code (N);
2141 Analyze_Dimension (N);
2142 end Analyze_Return_Statement;
2144 -------------------------------------
2145 -- Analyze_Simple_Return_Statement --
2146 -------------------------------------
2148 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2150 if Present (Expression (N)) then
2151 Mark_Coextensions (N, Expression (N));
2154 Analyze_Return_Statement (N);
2155 end Analyze_Simple_Return_Statement;
2157 -------------------------
2158 -- Analyze_Return_Type --
2159 -------------------------
2161 procedure Analyze_Return_Type (N : Node_Id) is
2162 Designator : constant Entity_Id := Defining_Entity (N);
2163 Typ : Entity_Id := Empty;
2166 -- Normal case where result definition does not indicate an error
2168 if Result_Definition (N) /= Error then
2169 if Nkind (Result_Definition (N)) = N_Access_Definition then
2170 Check_SPARK_05_Restriction
2171 ("access result is not allowed", Result_Definition (N));
2173 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2176 AD : constant Node_Id :=
2177 Access_To_Subprogram_Definition (Result_Definition (N));
2179 if Present (AD) and then Protected_Present (AD) then
2180 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2182 Typ := Access_Definition (N, Result_Definition (N));
2186 Set_Parent (Typ, Result_Definition (N));
2187 Set_Is_Local_Anonymous_Access (Typ);
2188 Set_Etype (Designator, Typ);
2190 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2192 Null_Exclusion_Static_Checks (N);
2194 -- Subtype_Mark case
2197 Find_Type (Result_Definition (N));
2198 Typ := Entity (Result_Definition (N));
2199 Set_Etype (Designator, Typ);
2201 -- Unconstrained array as result is not allowed in SPARK
2203 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2204 Check_SPARK_05_Restriction
2205 ("returning an unconstrained array is not allowed",
2206 Result_Definition (N));
2209 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2211 Null_Exclusion_Static_Checks (N);
2213 -- If a null exclusion is imposed on the result type, then create
2214 -- a null-excluding itype (an access subtype) and use it as the
2215 -- function's Etype. Note that the null exclusion checks are done
2216 -- right before this, because they don't get applied to types that
2217 -- do not come from source.
2219 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2220 Set_Etype (Designator,
2221 Create_Null_Excluding_Itype
2224 Scope_Id => Scope (Current_Scope)));
2226 -- The new subtype must be elaborated before use because
2227 -- it is visible outside of the function. However its base
2228 -- type may not be frozen yet, so the reference that will
2229 -- force elaboration must be attached to the freezing of
2232 -- If the return specification appears on a proper body,
2233 -- the subtype will have been created already on the spec.
2235 if Is_Frozen (Typ) then
2236 if Nkind (Parent (N)) = N_Subprogram_Body
2237 and then Nkind (Parent (Parent (N))) = N_Subunit
2241 Build_Itype_Reference (Etype (Designator), Parent (N));
2245 Ensure_Freeze_Node (Typ);
2248 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2250 Set_Itype (IR, Etype (Designator));
2251 Append_Freeze_Actions (Typ, New_List (IR));
2256 Set_Etype (Designator, Typ);
2259 if Ekind (Typ) = E_Incomplete_Type
2260 or else (Is_Class_Wide_Type (Typ)
2261 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2263 -- AI05-0151: Tagged incomplete types are allowed in all formal
2264 -- parts. Untagged incomplete types are not allowed in bodies.
2265 -- As a consequence, limited views cannot appear in a basic
2266 -- declaration that is itself within a body, because there is
2267 -- no point at which the non-limited view will become visible.
2269 if Ada_Version >= Ada_2012 then
2270 if From_Limited_With (Typ) and then In_Package_Body then
2272 ("invalid use of incomplete type&",
2273 Result_Definition (N), Typ);
2275 -- The return type of a subprogram body cannot be of a
2276 -- formal incomplete type.
2278 elsif Is_Generic_Type (Typ)
2279 and then Nkind (Parent (N)) = N_Subprogram_Body
2282 ("return type cannot be a formal incomplete type",
2283 Result_Definition (N));
2285 elsif Is_Class_Wide_Type (Typ)
2286 and then Is_Generic_Type (Root_Type (Typ))
2287 and then Nkind (Parent (N)) = N_Subprogram_Body
2290 ("return type cannot be a formal incomplete type",
2291 Result_Definition (N));
2293 elsif Is_Tagged_Type (Typ) then
2296 -- Use is legal in a thunk generated for an operation
2297 -- inherited from a progenitor.
2299 elsif Is_Thunk (Designator)
2300 and then Present (Non_Limited_View (Typ))
2304 elsif Nkind (Parent (N)) = N_Subprogram_Body
2305 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2309 ("invalid use of untagged incomplete type&",
2313 -- The type must be completed in the current package. This
2314 -- is checked at the end of the package declaration when
2315 -- Taft-amendment types are identified. If the return type
2316 -- is class-wide, there is no required check, the type can
2317 -- be a bona fide TAT.
2319 if Ekind (Scope (Current_Scope)) = E_Package
2320 and then In_Private_Part (Scope (Current_Scope))
2321 and then not Is_Class_Wide_Type (Typ)
2323 Append_Elmt (Designator, Private_Dependents (Typ));
2328 ("invalid use of incomplete type&", Designator, Typ);
2333 -- Case where result definition does indicate an error
2336 Set_Etype (Designator, Any_Type);
2338 end Analyze_Return_Type;
2340 -----------------------------
2341 -- Analyze_Subprogram_Body --
2342 -----------------------------
2344 procedure Analyze_Subprogram_Body (N : Node_Id) is
2345 Loc : constant Source_Ptr := Sloc (N);
2346 Body_Spec : constant Node_Id := Specification (N);
2347 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2350 if Debug_Flag_C then
2351 Write_Str ("==> subprogram body ");
2352 Write_Name (Chars (Body_Id));
2353 Write_Str (" from ");
2354 Write_Location (Loc);
2359 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2361 -- The real work is split out into the helper, so it can do "return;"
2362 -- without skipping the debug output:
2364 Analyze_Subprogram_Body_Helper (N);
2366 if Debug_Flag_C then
2368 Write_Str ("<== subprogram body ");
2369 Write_Name (Chars (Body_Id));
2370 Write_Str (" from ");
2371 Write_Location (Loc);
2374 end Analyze_Subprogram_Body;
2376 ------------------------------------
2377 -- Analyze_Subprogram_Body_Helper --
2378 ------------------------------------
2380 -- This procedure is called for regular subprogram bodies, generic bodies,
2381 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2382 -- specification matters, and is used to create a proper declaration for
2383 -- the subprogram, or to perform conformance checks.
2385 -- WARNING: This routine manages Ghost regions. Return statements must be
2386 -- replaced by gotos which jump to the end of the routine and restore the
2389 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2390 Body_Spec : Node_Id := Specification (N);
2391 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2392 Loc : constant Source_Ptr := Sloc (N);
2393 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2395 Conformant : Boolean;
2396 Desig_View : Entity_Id := Empty;
2397 Exch_Views : Elist_Id := No_Elist;
2399 Mask_Types : Elist_Id := No_Elist;
2400 Prot_Typ : Entity_Id := Empty;
2401 Spec_Decl : Node_Id := Empty;
2402 Spec_Id : Entity_Id;
2404 Last_Real_Spec_Entity : Entity_Id := Empty;
2405 -- When we analyze a separate spec, the entity chain ends up containing
2406 -- the formals, as well as any itypes generated during analysis of the
2407 -- default expressions for parameters, or the arguments of associated
2408 -- precondition/postcondition pragmas (which are analyzed in the context
2409 -- of the spec since they have visibility on formals).
2411 -- These entities belong with the spec and not the body. However we do
2412 -- the analysis of the body in the context of the spec (again to obtain
2413 -- visibility to the formals), and all the entities generated during
2414 -- this analysis end up also chained to the entity chain of the spec.
2415 -- But they really belong to the body, and there is circuitry to move
2416 -- them from the spec to the body.
2418 -- However, when we do this move, we don't want to move the real spec
2419 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2420 -- variable points to the last real spec entity, so we only move those
2421 -- chained beyond that point. It is initialized to Empty to deal with
2422 -- the case where there is no separate spec.
2424 function Body_Has_Contract return Boolean;
2425 -- Check whether unanalyzed body has an aspect or pragma that may
2426 -- generate a SPARK contract.
2428 function Body_Has_SPARK_Mode_On return Boolean;
2429 -- Check whether SPARK_Mode On applies to the subprogram body, either
2430 -- because it is specified directly on the body, or because it is
2431 -- inherited from the enclosing subprogram or package.
2433 procedure Build_Subprogram_Declaration;
2434 -- Create a matching subprogram declaration for subprogram body N
2436 procedure Check_Anonymous_Return;
2437 -- Ada 2005: if a function returns an access type that denotes a task,
2438 -- or a type that contains tasks, we must create a master entity for
2439 -- the anonymous type, which typically will be used in an allocator
2440 -- in the body of the function.
2442 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2443 -- Look ahead to recognize a pragma that may appear after the body.
2444 -- If there is a previous spec, check that it appears in the same
2445 -- declarative part. If the pragma is Inline_Always, perform inlining
2446 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2447 -- If the body acts as a spec, and inlining is required, we create a
2448 -- subprogram declaration for it, in order to attach the body to inline.
2449 -- If pragma does not appear after the body, check whether there is
2450 -- an inline pragma before any local declarations.
2452 procedure Check_Missing_Return;
2453 -- Checks for a function with a no return statements, and also performs
2454 -- the warning checks implemented by Check_Returns. In formal mode, also
2455 -- verify that a function ends with a RETURN and that a procedure does
2456 -- not contain any RETURN.
2458 function Disambiguate_Spec return Entity_Id;
2459 -- When a primitive is declared between the private view and the full
2460 -- view of a concurrent type which implements an interface, a special
2461 -- mechanism is used to find the corresponding spec of the primitive
2464 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2465 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2466 -- incomplete types coming from a limited context and replace their
2467 -- limited views with the non-limited ones. Return the list of changes
2468 -- to be used to undo the transformation.
2470 function Is_Private_Concurrent_Primitive
2471 (Subp_Id : Entity_Id) return Boolean;
2472 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2473 -- type that implements an interface and has a private view.
2475 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2476 -- N is the body generated for an expression function that is not a
2477 -- completion and Spec_Id the defining entity of its spec. Mark all
2478 -- the not-yet-frozen types referenced by the simple return statement
2479 -- of the function as formally frozen.
2481 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2482 -- Undo the transformation done by Exchange_Limited_Views.
2484 procedure Set_Trivial_Subprogram (N : Node_Id);
2485 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2486 -- subprogram whose body is being analyzed. N is the statement node
2487 -- causing the flag to be set, if the following statement is a return
2488 -- of an entity, we mark the entity as set in source to suppress any
2489 -- warning on the stylized use of function stubs with a dummy return.
2491 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2492 -- Undo the transformation done by Mask_Unfrozen_Types
2494 procedure Verify_Overriding_Indicator;
2495 -- If there was a previous spec, the entity has been entered in the
2496 -- current scope previously. If the body itself carries an overriding
2497 -- indicator, check that it is consistent with the known status of the
2500 -----------------------
2501 -- Body_Has_Contract --
2502 -----------------------
2504 function Body_Has_Contract return Boolean is
2505 Decls : constant List_Id := Declarations (N);
2509 -- Check for aspects that may generate a contract
2511 if Present (Aspect_Specifications (N)) then
2512 Item := First (Aspect_Specifications (N));
2513 while Present (Item) loop
2514 if Is_Subprogram_Contract_Annotation (Item) then
2522 -- Check for pragmas that may generate a contract
2524 if Present (Decls) then
2525 Item := First (Decls);
2526 while Present (Item) loop
2527 if Nkind (Item) = N_Pragma
2528 and then Is_Subprogram_Contract_Annotation (Item)
2538 end Body_Has_Contract;
2540 ----------------------------
2541 -- Body_Has_SPARK_Mode_On --
2542 ----------------------------
2544 function Body_Has_SPARK_Mode_On return Boolean is
2545 Decls : constant List_Id := Declarations (N);
2549 -- Check for SPARK_Mode aspect
2551 if Present (Aspect_Specifications (N)) then
2552 Item := First (Aspect_Specifications (N));
2553 while Present (Item) loop
2554 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2555 return Get_SPARK_Mode_From_Annotation (Item) = On;
2562 -- Check for SPARK_Mode pragma
2564 if Present (Decls) then
2565 Item := First (Decls);
2566 while Present (Item) loop
2568 -- Pragmas that apply to a subprogram body are usually grouped
2569 -- together. Look for a potential pragma SPARK_Mode among them.
2571 if Nkind (Item) = N_Pragma then
2572 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2573 return Get_SPARK_Mode_From_Annotation (Item) = On;
2576 -- Otherwise the first non-pragma declarative item terminates
2577 -- the region where pragma SPARK_Mode may appear.
2587 -- Otherwise, the applicable SPARK_Mode is inherited from the
2588 -- enclosing subprogram or package.
2590 return SPARK_Mode = On;
2591 end Body_Has_SPARK_Mode_On;
2593 ----------------------------------
2594 -- Build_Subprogram_Declaration --
2595 ----------------------------------
2597 procedure Build_Subprogram_Declaration is
2598 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2599 -- Relocate certain categorization pragmas from the declarative list
2600 -- of subprogram body From and insert them after node To. The pragmas
2603 -- Volatile_Function
2604 -- Also copy pragma SPARK_Mode if present in the declarative list
2605 -- of subprogram body From and insert it after node To. This pragma
2606 -- should not be moved, as it applies to the body too.
2612 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2614 Next_Decl : Node_Id;
2617 pragma Assert (Nkind (From) = N_Subprogram_Body);
2619 -- The destination node must be part of a list, as the pragmas are
2620 -- inserted after it.
2622 pragma Assert (Is_List_Member (To));
2624 -- Inspect the declarations of the subprogram body looking for
2625 -- specific pragmas.
2627 Decl := First (Declarations (N));
2628 while Present (Decl) loop
2629 Next_Decl := Next (Decl);
2631 if Nkind (Decl) = N_Pragma then
2632 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2633 Insert_After (To, New_Copy_Tree (Decl));
2635 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2637 Name_Volatile_Function)
2640 Insert_After (To, Decl);
2651 Subp_Decl : Node_Id;
2653 -- Start of processing for Build_Subprogram_Declaration
2656 -- Create a matching subprogram spec using the profile of the body.
2657 -- The structure of the tree is identical, but has new entities for
2658 -- the defining unit name and formal parameters.
2661 Make_Subprogram_Declaration (Loc,
2662 Specification => Copy_Subprogram_Spec (Body_Spec));
2663 Set_Comes_From_Source (Subp_Decl, True);
2665 -- Relocate the aspects and relevant pragmas from the subprogram body
2666 -- to the generated spec because it acts as the initial declaration.
2668 Insert_Before (N, Subp_Decl);
2669 Move_Aspects (N, To => Subp_Decl);
2670 Move_Pragmas (N, To => Subp_Decl);
2672 -- Ensure that the generated corresponding spec and original body
2673 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2674 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2675 -- correctly set for local subprograms.
2677 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2679 Analyze (Subp_Decl);
2681 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2682 -- the body since the expander may generate calls using that entity.
2683 -- Required to ensure that Expand_Call rewrites calls to this
2684 -- function by calls to the built procedure.
2686 if Modify_Tree_For_C
2687 and then Nkind (Body_Spec) = N_Function_Specification
2689 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2691 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2692 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2693 Corresponding_Procedure
2694 (Defining_Entity (Specification (Subp_Decl))));
2697 -- Analyze any relocated source pragmas or pragmas created for aspect
2700 Decl := Next (Subp_Decl);
2701 while Present (Decl) loop
2703 -- Stop the search for pragmas once the body has been reached as
2704 -- this terminates the region where pragmas may appear.
2709 elsif Nkind (Decl) = N_Pragma then
2716 Spec_Id := Defining_Entity (Subp_Decl);
2717 Set_Corresponding_Spec (N, Spec_Id);
2719 -- Mark the generated spec as a source construct to ensure that all
2720 -- calls to it are properly registered in ALI files for GNATprove.
2722 Set_Comes_From_Source (Spec_Id, True);
2724 -- Ensure that the specs of the subprogram declaration and its body
2725 -- are identical, otherwise they will appear non-conformant due to
2726 -- rewritings in the default values of formal parameters.
2728 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2729 Set_Specification (N, Body_Spec);
2730 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2731 end Build_Subprogram_Declaration;
2733 ----------------------------
2734 -- Check_Anonymous_Return --
2735 ----------------------------
2737 procedure Check_Anonymous_Return is
2743 if Present (Spec_Id) then
2749 if Ekind (Scop) = E_Function
2750 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2751 and then not Is_Thunk (Scop)
2753 -- Skip internally built functions which handle the case of
2754 -- a null access (see Expand_Interface_Conversion)
2756 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2757 and then not Comes_From_Source (Parent (Scop)))
2759 and then (Has_Task (Designated_Type (Etype (Scop)))
2761 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2763 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2764 and then Expander_Active
2766 -- Avoid cases with no tasking support
2768 and then RTE_Available (RE_Current_Master)
2769 and then not Restriction_Active (No_Task_Hierarchy)
2772 Make_Object_Declaration (Loc,
2773 Defining_Identifier =>
2774 Make_Defining_Identifier (Loc, Name_uMaster),
2775 Constant_Present => True,
2776 Object_Definition =>
2777 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2779 Make_Explicit_Dereference (Loc,
2780 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2782 if Present (Declarations (N)) then
2783 Prepend (Decl, Declarations (N));
2785 Set_Declarations (N, New_List (Decl));
2788 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2789 Set_Has_Master_Entity (Scop);
2791 -- Now mark the containing scope as a task master
2794 while Nkind (Par) /= N_Compilation_Unit loop
2795 Par := Parent (Par);
2796 pragma Assert (Present (Par));
2798 -- If we fall off the top, we are at the outer level, and
2799 -- the environment task is our effective master, so nothing
2803 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2805 Set_Is_Task_Master (Par, True);
2810 end Check_Anonymous_Return;
2812 -------------------------
2813 -- Check_Inline_Pragma --
2814 -------------------------
2816 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2820 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2821 -- True when N is a pragma Inline or Inline_Always that applies
2822 -- to this subprogram.
2824 -----------------------
2825 -- Is_Inline_Pragma --
2826 -----------------------
2828 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2830 if Nkind (N) = N_Pragma
2832 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2833 or else (Pragma_Name_Unmapped (N) = Name_Inline
2835 (Front_End_Inlining or else Optimization_Level > 0)))
2836 and then Present (Pragma_Argument_Associations (N))
2839 Pragma_Arg : Node_Id :=
2840 Expression (First (Pragma_Argument_Associations (N)));
2842 if Nkind (Pragma_Arg) = N_Selected_Component then
2843 Pragma_Arg := Selector_Name (Pragma_Arg);
2846 return Chars (Pragma_Arg) = Chars (Body_Id);
2852 end Is_Inline_Pragma;
2854 -- Start of processing for Check_Inline_Pragma
2857 if not Expander_Active then
2861 if Is_List_Member (N)
2862 and then Present (Next (N))
2863 and then Is_Inline_Pragma (Next (N))
2867 elsif Nkind (N) /= N_Subprogram_Body_Stub
2868 and then Present (Declarations (N))
2869 and then Is_Inline_Pragma (First (Declarations (N)))
2871 Prag := First (Declarations (N));
2877 if Present (Prag) then
2878 if Present (Spec_Id) then
2879 if Is_List_Member (N)
2880 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2881 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2887 -- Create a subprogram declaration, to make treatment uniform.
2888 -- Make the sloc of the subprogram name that of the entity in
2889 -- the body, so that style checks find identical strings.
2892 Subp : constant Entity_Id :=
2893 Make_Defining_Identifier
2894 (Sloc (Body_Id), Chars (Body_Id));
2895 Decl : constant Node_Id :=
2896 Make_Subprogram_Declaration (Loc,
2898 New_Copy_Tree (Specification (N)));
2901 -- Link the body and the generated spec
2903 Set_Corresponding_Body (Decl, Body_Id);
2904 Set_Corresponding_Spec (N, Subp);
2906 Set_Defining_Unit_Name (Specification (Decl), Subp);
2908 -- To ensure proper coverage when body is inlined, indicate
2909 -- whether the subprogram comes from source.
2911 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2913 if Present (First_Formal (Body_Id)) then
2914 Plist := Copy_Parameter_List (Body_Id);
2915 Set_Parameter_Specifications
2916 (Specification (Decl), Plist);
2919 -- Move aspects to the new spec
2921 if Has_Aspects (N) then
2922 Move_Aspects (N, To => Decl);
2925 Insert_Before (N, Decl);
2928 Set_Has_Pragma_Inline (Subp);
2930 if Pragma_Name (Prag) = Name_Inline_Always then
2931 Set_Is_Inlined (Subp);
2932 Set_Has_Pragma_Inline_Always (Subp);
2935 -- Prior to copying the subprogram body to create a template
2936 -- for it for subsequent inlining, remove the pragma from
2937 -- the current body so that the copy that will produce the
2938 -- new body will start from a completely unanalyzed tree.
2940 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2941 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2948 end Check_Inline_Pragma;
2950 --------------------------
2951 -- Check_Missing_Return --
2952 --------------------------
2954 procedure Check_Missing_Return is
2956 Missing_Ret : Boolean;
2959 if Nkind (Body_Spec) = N_Function_Specification then
2960 if Present (Spec_Id) then
2966 if Return_Present (Id) then
2967 Check_Returns (HSS, 'F', Missing_Ret);
2970 Set_Has_Missing_Return (Id);
2973 -- Within a premature instantiation of a package with no body, we
2974 -- build completions of the functions therein, with a Raise
2975 -- statement. No point in complaining about a missing return in
2978 elsif Ekind (Id) = E_Function
2979 and then In_Instance
2980 and then Present (Statements (HSS))
2981 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
2985 elsif Is_Generic_Subprogram (Id)
2986 or else not Is_Machine_Code_Subprogram (Id)
2988 Error_Msg_N ("missing RETURN statement in function body", N);
2991 -- If procedure with No_Return, check returns
2993 elsif Nkind (Body_Spec) = N_Procedure_Specification
2994 and then Present (Spec_Id)
2995 and then No_Return (Spec_Id)
2997 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
3000 -- Special checks in SPARK mode
3002 if Nkind (Body_Spec) = N_Function_Specification then
3004 -- In SPARK mode, last statement of a function should be a return
3007 Stat : constant Node_Id := Last_Source_Statement (HSS);
3010 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3011 N_Extended_Return_Statement)
3013 Check_SPARK_05_Restriction
3014 ("last statement in function should be RETURN", Stat);
3018 -- In SPARK mode, verify that a procedure has no return
3020 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3021 if Present (Spec_Id) then
3027 -- Would be nice to point to return statement here, can we
3028 -- borrow the Check_Returns procedure here ???
3030 if Return_Present (Id) then
3031 Check_SPARK_05_Restriction
3032 ("procedure should not have RETURN", N);
3035 end Check_Missing_Return;
3037 -----------------------
3038 -- Disambiguate_Spec --
3039 -----------------------
3041 function Disambiguate_Spec return Entity_Id is
3042 Priv_Spec : Entity_Id;
3045 procedure Replace_Types (To_Corresponding : Boolean);
3046 -- Depending on the flag, replace the type of formal parameters of
3047 -- Body_Id if it is a concurrent type implementing interfaces with
3048 -- the corresponding record type or the other way around.
3050 procedure Replace_Types (To_Corresponding : Boolean) is
3052 Formal_Typ : Entity_Id;
3055 Formal := First_Formal (Body_Id);
3056 while Present (Formal) loop
3057 Formal_Typ := Etype (Formal);
3059 if Is_Class_Wide_Type (Formal_Typ) then
3060 Formal_Typ := Root_Type (Formal_Typ);
3063 -- From concurrent type to corresponding record
3065 if To_Corresponding then
3066 if Is_Concurrent_Type (Formal_Typ)
3067 and then Present (Corresponding_Record_Type (Formal_Typ))
3070 (Corresponding_Record_Type (Formal_Typ)))
3073 Corresponding_Record_Type (Formal_Typ));
3076 -- From corresponding record to concurrent type
3079 if Is_Concurrent_Record_Type (Formal_Typ)
3080 and then Present (Interfaces (Formal_Typ))
3083 Corresponding_Concurrent_Type (Formal_Typ));
3087 Next_Formal (Formal);
3091 -- Start of processing for Disambiguate_Spec
3094 -- Try to retrieve the specification of the body as is. All error
3095 -- messages are suppressed because the body may not have a spec in
3096 -- its current state.
3098 Spec_N := Find_Corresponding_Spec (N, False);
3100 -- It is possible that this is the body of a primitive declared
3101 -- between a private and a full view of a concurrent type. The
3102 -- controlling parameter of the spec carries the concurrent type,
3103 -- not the corresponding record type as transformed by Analyze_
3104 -- Subprogram_Specification. In such cases, we undo the change
3105 -- made by the analysis of the specification and try to find the
3108 -- Note that wrappers already have their corresponding specs and
3109 -- bodies set during their creation, so if the candidate spec is
3110 -- a wrapper, then we definitely need to swap all types to their
3111 -- original concurrent status.
3114 or else Is_Primitive_Wrapper (Spec_N)
3116 -- Restore all references of corresponding record types to the
3117 -- original concurrent types.
3119 Replace_Types (To_Corresponding => False);
3120 Priv_Spec := Find_Corresponding_Spec (N, False);
3122 -- The current body truly belongs to a primitive declared between
3123 -- a private and a full view. We leave the modified body as is,
3124 -- and return the true spec.
3126 if Present (Priv_Spec)
3127 and then Is_Private_Primitive (Priv_Spec)
3132 -- In case that this is some sort of error, restore the original
3133 -- state of the body.
3135 Replace_Types (To_Corresponding => True);
3139 end Disambiguate_Spec;
3141 ----------------------------
3142 -- Exchange_Limited_Views --
3143 ----------------------------
3145 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3146 Result : Elist_Id := No_Elist;
3148 procedure Detect_And_Exchange (Id : Entity_Id);
3149 -- Determine whether Id's type denotes an incomplete type associated
3150 -- with a limited with clause and exchange the limited view with the
3151 -- non-limited one when available. Note that the non-limited view
3152 -- may exist because of a with_clause in another unit in the context,
3153 -- but cannot be used because the current view of the enclosing unit
3154 -- is still a limited view.
3156 -------------------------
3157 -- Detect_And_Exchange --
3158 -------------------------
3160 procedure Detect_And_Exchange (Id : Entity_Id) is
3161 Typ : constant Entity_Id := Etype (Id);
3163 if From_Limited_With (Typ)
3164 and then Has_Non_Limited_View (Typ)
3165 and then not From_Limited_With (Scope (Typ))
3168 Result := New_Elmt_List;
3171 Prepend_Elmt (Typ, Result);
3172 Prepend_Elmt (Id, Result);
3173 Set_Etype (Id, Non_Limited_View (Typ));
3175 end Detect_And_Exchange;
3181 -- Start of processing for Exchange_Limited_Views
3184 -- Do not process subprogram bodies as they already use the non-
3185 -- limited view of types.
3187 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3191 -- Examine all formals and swap views when applicable
3193 Formal := First_Formal (Subp_Id);
3194 while Present (Formal) loop
3195 Detect_And_Exchange (Formal);
3197 Next_Formal (Formal);
3200 -- Process the return type of a function
3202 if Ekind (Subp_Id) = E_Function then
3203 Detect_And_Exchange (Subp_Id);
3207 end Exchange_Limited_Views;
3209 -------------------------------------
3210 -- Is_Private_Concurrent_Primitive --
3211 -------------------------------------
3213 function Is_Private_Concurrent_Primitive
3214 (Subp_Id : Entity_Id) return Boolean
3216 Formal_Typ : Entity_Id;
3219 if Present (First_Formal (Subp_Id)) then
3220 Formal_Typ := Etype (First_Formal (Subp_Id));
3222 if Is_Concurrent_Record_Type (Formal_Typ) then
3223 if Is_Class_Wide_Type (Formal_Typ) then
3224 Formal_Typ := Root_Type (Formal_Typ);
3227 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3230 -- The type of the first formal is a concurrent tagged type with
3234 Is_Concurrent_Type (Formal_Typ)
3235 and then Is_Tagged_Type (Formal_Typ)
3236 and then Has_Private_Declaration (Formal_Typ);
3240 end Is_Private_Concurrent_Primitive;
3242 -------------------------
3243 -- Mask_Unfrozen_Types --
3244 -------------------------
3246 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3247 Result : Elist_Id := No_Elist;
3249 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3250 -- Mask all types referenced in the subtree rooted at Node
3252 --------------------
3253 -- Mask_Type_Refs --
3254 --------------------
3256 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3257 procedure Mask_Type (Typ : Entity_Id);
3258 -- ??? what does this do?
3264 procedure Mask_Type (Typ : Entity_Id) is
3266 -- Skip Itypes created by the preanalysis
3269 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3274 if not Is_Frozen (Typ) then
3275 Set_Is_Frozen (Typ);
3276 Append_New_Elmt (Typ, Result);
3280 -- Start of processing for Mask_Type_Refs
3283 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3284 Mask_Type (Etype (Entity (Node)));
3286 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3287 Mask_Type (Scope (Entity (Node)));
3290 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3291 and then Present (Etype (Node))
3293 Mask_Type (Etype (Node));
3299 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3303 Return_Stmt : constant Node_Id :=
3304 First (Statements (Handled_Statement_Sequence (N)));
3306 -- Start of processing for Mask_Unfrozen_Types
3309 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3311 Mask_References (Expression (Return_Stmt));
3314 end Mask_Unfrozen_Types;
3316 ---------------------------
3317 -- Restore_Limited_Views --
3318 ---------------------------
3320 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3321 Elmt : Elmt_Id := First_Elmt (Restore_List);
3325 while Present (Elmt) loop
3328 Set_Etype (Id, Node (Elmt));
3331 end Restore_Limited_Views;
3333 ----------------------------
3334 -- Set_Trivial_Subprogram --
3335 ----------------------------
3337 procedure Set_Trivial_Subprogram (N : Node_Id) is
3338 Nxt : constant Node_Id := Next (N);
3341 Set_Is_Trivial_Subprogram (Body_Id);
3343 if Present (Spec_Id) then
3344 Set_Is_Trivial_Subprogram (Spec_Id);
3348 and then Nkind (Nxt) = N_Simple_Return_Statement
3349 and then No (Next (Nxt))
3350 and then Present (Expression (Nxt))
3351 and then Is_Entity_Name (Expression (Nxt))
3353 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3355 end Set_Trivial_Subprogram;
3357 ---------------------------
3358 -- Unmask_Unfrozen_Types --
3359 ---------------------------
3361 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3362 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3365 while Present (Elmt) loop
3366 Set_Is_Frozen (Node (Elmt), False);
3369 end Unmask_Unfrozen_Types;
3371 ---------------------------------
3372 -- Verify_Overriding_Indicator --
3373 ---------------------------------
3375 procedure Verify_Overriding_Indicator is
3377 if Must_Override (Body_Spec) then
3378 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3379 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3383 elsif not Present (Overridden_Operation (Spec_Id)) then
3385 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3387 -- Overriding indicators aren't allowed for protected subprogram
3388 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3389 -- this to a warning if -gnatd.E is enabled.
3391 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3392 Error_Msg_Warn := Error_To_Warning;
3394 ("<<overriding indicator not allowed for protected "
3395 & "subprogram body", Body_Spec);
3398 elsif Must_Not_Override (Body_Spec) then
3399 if Present (Overridden_Operation (Spec_Id)) then
3401 ("subprogram& overrides inherited operation",
3402 Body_Spec, Spec_Id);
3404 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3405 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3408 ("subprogram& overrides predefined operator ",
3409 Body_Spec, Spec_Id);
3411 -- Overriding indicators aren't allowed for protected subprogram
3412 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3413 -- this to a warning if -gnatd.E is enabled.
3415 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3416 Error_Msg_Warn := Error_To_Warning;
3419 ("<<overriding indicator not allowed "
3420 & "for protected subprogram body", Body_Spec);
3422 -- If this is not a primitive operation, then the overriding
3423 -- indicator is altogether illegal.
3425 elsif not Is_Primitive (Spec_Id) then
3427 ("overriding indicator only allowed "
3428 & "if subprogram is primitive", Body_Spec);
3431 -- If checking the style rule and the operation overrides, then
3432 -- issue a warning about a missing overriding_indicator. Protected
3433 -- subprogram bodies are excluded from this style checking, since
3434 -- they aren't primitives (even though their declarations can
3435 -- override) and aren't allowed to have an overriding_indicator.
3438 and then Present (Overridden_Operation (Spec_Id))
3439 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3441 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3442 Style.Missing_Overriding (N, Body_Id);
3445 and then Can_Override_Operator (Spec_Id)
3446 and then not In_Predefined_Unit (Spec_Id)
3448 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3449 Style.Missing_Overriding (N, Body_Id);
3451 end Verify_Overriding_Indicator;
3455 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3456 Saved_ISMP : constant Boolean :=
3457 Ignore_SPARK_Mode_Pragmas_In_Instance;
3458 -- Save the Ghost and SPARK mode-related data to restore on exit
3460 -- Start of processing for Analyze_Subprogram_Body_Helper
3463 -- A [generic] subprogram body freezes the contract of the nearest
3464 -- enclosing package body and all other contracts encountered in the
3465 -- same declarative part up to and excluding the subprogram body:
3467 -- package body Nearest_Enclosing_Package
3468 -- with Refined_State => (State => Constit)
3472 -- procedure Freezes_Enclosing_Package_Body
3473 -- with Refined_Depends => (Input => Constit) ...
3475 -- This ensures that any annotations referenced by the contract of the
3476 -- [generic] subprogram body are available. This form of freezing is
3477 -- decoupled from the usual Freeze_xxx mechanism because it must also
3478 -- work in the context of generics where normal freezing is disabled.
3480 -- Only bodies coming from source should cause this type of freezing.
3481 -- Expression functions that act as bodies and complete an initial
3482 -- declaration must be included in this category, hence the use of
3485 if Comes_From_Source (Original_Node (N)) then
3486 Freeze_Previous_Contracts (N);
3489 -- Generic subprograms are handled separately. They always have a
3490 -- generic specification. Determine whether current scope has a
3491 -- previous declaration.
3493 -- If the subprogram body is defined within an instance of the same
3494 -- name, the instance appears as a package renaming, and will be hidden
3495 -- within the subprogram.
3497 if Present (Prev_Id)
3498 and then not Is_Overloadable (Prev_Id)
3499 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3500 or else Comes_From_Source (Prev_Id))
3502 if Is_Generic_Subprogram (Prev_Id) then
3505 -- A subprogram body is Ghost when it is stand alone and subject
3506 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3507 -- the mode now to ensure that any nodes generated during analysis
3508 -- and expansion are properly marked as Ghost.
3510 Mark_And_Set_Ghost_Body (N, Spec_Id);
3512 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3513 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3515 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3517 if Nkind (N) = N_Subprogram_Body then
3518 HSS := Handled_Statement_Sequence (N);
3519 Check_Missing_Return;
3524 -- Otherwise a previous entity conflicts with the subprogram name.
3525 -- Attempting to enter name will post error.
3528 Enter_Name (Body_Id);
3532 -- Non-generic case, find the subprogram declaration, if one was seen,
3533 -- or enter new overloaded entity in the current scope. If the
3534 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3535 -- part of the context of one of its subunits. No need to redo the
3538 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3542 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3544 if Nkind (N) = N_Subprogram_Body_Stub
3545 or else No (Corresponding_Spec (N))
3547 if Is_Private_Concurrent_Primitive (Body_Id) then
3548 Spec_Id := Disambiguate_Spec;
3550 -- A subprogram body is Ghost when it is stand alone and
3551 -- subject to pragma Ghost or when the corresponding spec is
3552 -- Ghost. Set the mode now to ensure that any nodes generated
3553 -- during analysis and expansion are properly marked as Ghost.
3555 Mark_And_Set_Ghost_Body (N, Spec_Id);
3558 Spec_Id := Find_Corresponding_Spec (N);
3560 -- A subprogram body is Ghost when it is stand alone and
3561 -- subject to pragma Ghost or when the corresponding spec is
3562 -- Ghost. Set the mode now to ensure that any nodes generated
3563 -- during analysis and expansion are properly marked as Ghost.
3565 Mark_And_Set_Ghost_Body (N, Spec_Id);
3567 -- In GNATprove mode, if the body has no previous spec, create
3568 -- one so that the inlining machinery can operate properly.
3569 -- Transfer aspects, if any, to the new spec, so that they
3570 -- are legal and can be processed ahead of the body.
3571 -- We make two copies of the given spec, one for the new
3572 -- declaration, and one for the body.
3574 if No (Spec_Id) and then GNATprove_Mode
3576 -- Inlining does not apply during pre-analysis of code
3578 and then Full_Analysis
3580 -- Inlining only applies to full bodies, not stubs
3582 and then Nkind (N) /= N_Subprogram_Body_Stub
3584 -- Inlining only applies to bodies in the source code, not to
3585 -- those generated by the compiler. In particular, expression
3586 -- functions, whose body is generated by the compiler, are
3587 -- treated specially by GNATprove.
3589 and then Comes_From_Source (Body_Id)
3591 -- This cannot be done for a compilation unit, which is not
3592 -- in a context where we can insert a new spec.
3594 and then Is_List_Member (N)
3596 -- Inlining only applies to subprograms without contracts,
3597 -- as a contract is a sign that GNATprove should perform a
3598 -- modular analysis of the subprogram instead of a contextual
3599 -- analysis at each call site. The same test is performed in
3600 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3601 -- here in another form (because the contract has not been
3602 -- attached to the body) to avoid front-end errors in case
3603 -- pragmas are used instead of aspects, because the
3604 -- corresponding pragmas in the body would not be transferred
3605 -- to the spec, leading to legality errors.
3607 and then not Body_Has_Contract
3608 and then not Inside_A_Generic
3610 Build_Subprogram_Declaration;
3612 -- If this is a function that returns a constrained array, and
3613 -- we are generating SPARK_For_C, create subprogram declaration
3614 -- to simplify subsequent C generation.
3617 and then Modify_Tree_For_C
3618 and then Nkind (Body_Spec) = N_Function_Specification
3619 and then Is_Array_Type (Etype (Body_Id))
3620 and then Is_Constrained (Etype (Body_Id))
3622 Build_Subprogram_Declaration;
3626 -- If this is a duplicate body, no point in analyzing it
3628 if Error_Posted (N) then
3632 -- A subprogram body should cause freezing of its own declaration,
3633 -- but if there was no previous explicit declaration, then the
3634 -- subprogram will get frozen too late (there may be code within
3635 -- the body that depends on the subprogram having been frozen,
3636 -- such as uses of extra formals), so we force it to be frozen
3637 -- here. Same holds if the body and spec are compilation units.
3638 -- Finally, if the return type is an anonymous access to protected
3639 -- subprogram, it must be frozen before the body because its
3640 -- expansion has generated an equivalent type that is used when
3641 -- elaborating the body.
3643 -- An exception in the case of Ada 2012, AI05-177: The bodies
3644 -- created for expression functions do not freeze.
3647 and then Nkind (Original_Node (N)) /= N_Expression_Function
3649 Freeze_Before (N, Body_Id);
3651 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3652 Freeze_Before (N, Spec_Id);
3654 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3655 Freeze_Before (N, Etype (Body_Id));
3659 Spec_Id := Corresponding_Spec (N);
3661 -- A subprogram body is Ghost when it is stand alone and subject
3662 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3663 -- the mode now to ensure that any nodes generated during analysis
3664 -- and expansion are properly marked as Ghost.
3666 Mark_And_Set_Ghost_Body (N, Spec_Id);
3670 -- Previously we scanned the body to look for nested subprograms, and
3671 -- rejected an inline directive if nested subprograms were present,
3672 -- because the back-end would generate conflicting symbols for the
3673 -- nested bodies. This is now unnecessary.
3675 -- Look ahead to recognize a pragma Inline that appears after the body
3677 Check_Inline_Pragma (Spec_Id);
3679 -- Deal with special case of a fully private operation in the body of
3680 -- the protected type. We must create a declaration for the subprogram,
3681 -- in order to attach the protected subprogram that will be used in
3682 -- internal calls. We exclude compiler generated bodies from the
3683 -- expander since the issue does not arise for those cases.
3686 and then Comes_From_Source (N)
3687 and then Is_Protected_Type (Current_Scope)
3689 Spec_Id := Build_Private_Protected_Declaration (N);
3692 -- If we are generating C and this is a function returning a constrained
3693 -- array type for which we must create a procedure with an extra out
3694 -- parameter, build and analyze the body now. The procedure declaration
3695 -- has already been created. We reuse the source body of the function,
3696 -- because in an instance it may contain global references that cannot
3697 -- be reanalyzed. The source function itself is not used any further,
3698 -- so we mark it as having a completion. If the subprogram is a stub the
3699 -- transformation is done later, when the proper body is analyzed.
3702 and then Modify_Tree_For_C
3703 and then Present (Spec_Id)
3704 and then Ekind (Spec_Id) = E_Function
3705 and then Nkind (N) /= N_Subprogram_Body_Stub
3706 and then Rewritten_For_C (Spec_Id)
3708 Set_Has_Completion (Spec_Id);
3710 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3713 -- The entity for the created procedure must remain invisible, so it
3714 -- does not participate in resolution of subsequent references to the
3717 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3721 -- If a separate spec is present, then deal with freezing issues
3723 if Present (Spec_Id) then
3724 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3725 Verify_Overriding_Indicator;
3727 -- In general, the spec will be frozen when we start analyzing the
3728 -- body. However, for internally generated operations, such as
3729 -- wrapper functions for inherited operations with controlling
3730 -- results, the spec may not have been frozen by the time we expand
3731 -- the freeze actions that include the bodies. In particular, extra
3732 -- formals for accessibility or for return-in-place may need to be
3733 -- generated. Freeze nodes, if any, are inserted before the current
3734 -- body. These freeze actions are also needed in ASIS mode and in
3735 -- Compile_Only mode to enable the proper back-end type annotations.
3736 -- They are necessary in any case to insure order of elaboration
3739 if not Is_Frozen (Spec_Id)
3740 and then (Expander_Active
3742 or else (Operating_Mode = Check_Semantics
3743 and then Serious_Errors_Detected = 0))
3745 -- The body generated for an expression function that is not a
3746 -- completion is a freeze point neither for the profile nor for
3747 -- anything else. That's why, in order to prevent any freezing
3748 -- during analysis, we need to mask types declared outside the
3749 -- expression that are not yet frozen.
3751 if Nkind (N) = N_Subprogram_Body
3752 and then Was_Expression_Function (N)
3753 and then not Has_Completion (Spec_Id)
3755 Set_Is_Frozen (Spec_Id);
3756 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3758 Set_Has_Delayed_Freeze (Spec_Id);
3759 Freeze_Before (N, Spec_Id);
3764 -- If the subprogram has a class-wide clone, build its body as a copy
3765 -- of the original body, and rewrite body of original subprogram as a
3766 -- wrapper that calls the clone.
3768 if Present (Spec_Id)
3769 and then Present (Class_Wide_Clone (Spec_Id))
3770 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3772 Build_Class_Wide_Clone_Body (Spec_Id, N);
3774 -- This is the new body for the existing primitive operation
3776 Rewrite (N, Build_Class_Wide_Clone_Call
3777 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3778 Set_Has_Completion (Spec_Id, False);
3783 -- Place subprogram on scope stack, and make formals visible. If there
3784 -- is a spec, the visible entity remains that of the spec.
3786 if Present (Spec_Id) then
3787 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3789 if Is_Child_Unit (Spec_Id) then
3790 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3794 Style.Check_Identifier (Body_Id, Spec_Id);
3797 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3798 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3800 if Is_Abstract_Subprogram (Spec_Id) then
3801 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3805 Set_Convention (Body_Id, Convention (Spec_Id));
3806 Set_Has_Completion (Spec_Id);
3808 if Is_Protected_Type (Scope (Spec_Id)) then
3809 Prot_Typ := Scope (Spec_Id);
3812 -- If this is a body generated for a renaming, do not check for
3813 -- full conformance. The check is redundant, because the spec of
3814 -- the body is a copy of the spec in the renaming declaration,
3815 -- and the test can lead to spurious errors on nested defaults.
3817 if Present (Spec_Decl)
3818 and then not Comes_From_Source (N)
3820 (Nkind (Original_Node (Spec_Decl)) =
3821 N_Subprogram_Renaming_Declaration
3822 or else (Present (Corresponding_Body (Spec_Decl))
3824 Nkind (Unit_Declaration_Node
3825 (Corresponding_Body (Spec_Decl))) =
3826 N_Subprogram_Renaming_Declaration))
3830 -- Conversely, the spec may have been generated for specless body
3831 -- with an inline pragma. The entity comes from source, which is
3832 -- both semantically correct and necessary for proper inlining.
3833 -- The subprogram declaration itself is not in the source.
3835 elsif Comes_From_Source (N)
3836 and then Present (Spec_Decl)
3837 and then not Comes_From_Source (Spec_Decl)
3838 and then Has_Pragma_Inline (Spec_Id)
3845 Fully_Conformant, True, Conformant, Body_Id);
3848 -- If the body is not fully conformant, we have to decide if we
3849 -- should analyze it or not. If it has a really messed up profile
3850 -- then we probably should not analyze it, since we will get too
3851 -- many bogus messages.
3853 -- Our decision is to go ahead in the non-fully conformant case
3854 -- only if it is at least mode conformant with the spec. Note
3855 -- that the call to Check_Fully_Conformant has issued the proper
3856 -- error messages to complain about the lack of conformance.
3859 and then not Mode_Conformant (Body_Id, Spec_Id)
3865 if Spec_Id /= Body_Id then
3866 Reference_Body_Formals (Spec_Id, Body_Id);
3869 Set_Ekind (Body_Id, E_Subprogram_Body);
3871 if Nkind (N) = N_Subprogram_Body_Stub then
3872 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3877 Set_Corresponding_Spec (N, Spec_Id);
3879 -- Ada 2005 (AI-345): If the operation is a primitive operation
3880 -- of a concurrent type, the type of the first parameter has been
3881 -- replaced with the corresponding record, which is the proper
3882 -- run-time structure to use. However, within the body there may
3883 -- be uses of the formals that depend on primitive operations
3884 -- of the type (in particular calls in prefixed form) for which
3885 -- we need the original concurrent type. The operation may have
3886 -- several controlling formals, so the replacement must be done
3889 if Comes_From_Source (Spec_Id)
3890 and then Present (First_Entity (Spec_Id))
3891 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3892 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3893 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3894 and then Present (Corresponding_Concurrent_Type
3895 (Etype (First_Entity (Spec_Id))))
3898 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3902 Form := First_Formal (Spec_Id);
3903 while Present (Form) loop
3904 if Etype (Form) = Typ then
3905 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3913 -- Make the formals visible, and place subprogram on scope stack.
3914 -- This is also the point at which we set Last_Real_Spec_Entity
3915 -- to mark the entities which will not be moved to the body.
3917 Install_Formals (Spec_Id);
3918 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3920 -- Within an instance, add local renaming declarations so that
3921 -- gdb can retrieve the values of actuals more easily. This is
3922 -- only relevant if generating code (and indeed we definitely
3923 -- do not want these definitions -gnatc mode, because that would
3926 if Is_Generic_Instance (Spec_Id)
3927 and then Is_Wrapper_Package (Current_Scope)
3928 and then Expander_Active
3930 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3933 Push_Scope (Spec_Id);
3935 -- Make sure that the subprogram is immediately visible. For
3936 -- child units that have no separate spec this is indispensable.
3937 -- Otherwise it is safe albeit redundant.
3939 Set_Is_Immediately_Visible (Spec_Id);
3942 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3943 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3944 Set_Scope (Body_Id, Scope (Spec_Id));
3946 -- Case of subprogram body with no previous spec
3949 -- Check for style warning required
3953 -- Only apply check for source level subprograms for which checks
3954 -- have not been suppressed.
3956 and then Comes_From_Source (Body_Id)
3957 and then not Suppress_Style_Checks (Body_Id)
3959 -- No warnings within an instance
3961 and then not In_Instance
3963 -- No warnings for expression functions
3965 and then Nkind (Original_Node (N)) /= N_Expression_Function
3967 Style.Body_With_No_Spec (N);
3970 New_Overloaded_Entity (Body_Id);
3972 if Nkind (N) /= N_Subprogram_Body_Stub then
3973 Set_Acts_As_Spec (N);
3974 Generate_Definition (Body_Id);
3976 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3978 -- If the body is an entry wrapper created for an entry with
3979 -- preconditions, it must be compiled in the context of the
3980 -- enclosing synchronized object, because it may mention other
3981 -- operations of the type.
3983 if Is_Entry_Wrapper (Body_Id) then
3985 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
3988 Install_Declarations (Prot);
3992 Install_Formals (Body_Id);
3994 Push_Scope (Body_Id);
3997 -- For stubs and bodies with no previous spec, generate references to
4000 Generate_Reference_To_Formals (Body_Id);
4003 -- Entry barrier functions are generated outside the protected type and
4004 -- should not carry the SPARK_Mode of the enclosing context.
4006 if Nkind (N) = N_Subprogram_Body
4007 and then Is_Entry_Barrier_Function (N)
4011 -- The body is generated as part of expression function expansion. When
4012 -- the expression function appears in the visible declarations of a
4013 -- package, the body is added to the private declarations. Since both
4014 -- declarative lists may be subject to a different SPARK_Mode, inherit
4015 -- the mode of the spec.
4017 -- package P with SPARK_Mode is
4018 -- function Expr_Func ... is (...); -- original
4019 -- [function Expr_Func ...;] -- generated spec
4022 -- pragma SPARK_Mode (Off);
4023 -- [function Expr_Func ... is return ...;] -- generated body
4024 -- end P; -- mode is ON
4026 elsif not Comes_From_Source (N)
4027 and then Present (Spec_Id)
4028 and then Is_Expression_Function (Spec_Id)
4030 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4031 Set_SPARK_Pragma_Inherited
4032 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4034 -- Set the SPARK_Mode from the current context (may be overwritten later
4035 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4036 -- initially on a stand-alone subprogram body, but is then relocated to
4037 -- a generated corresponding spec. In this scenario the mode is shared
4038 -- between the spec and body.
4040 elsif No (SPARK_Pragma (Body_Id)) then
4041 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4042 Set_SPARK_Pragma_Inherited (Body_Id);
4045 -- A subprogram body may be instantiated or inlined at a later pass.
4046 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4047 -- applied to the initial declaration of the body.
4049 if Present (Spec_Id) then
4050 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4051 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4055 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4056 -- case the body is instantiated or inlined later and out of context.
4057 -- The body uses this attribute to restore the value of the global
4060 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4061 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4063 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4064 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4068 -- If this is the proper body of a stub, we must verify that the stub
4069 -- conforms to the body, and to the previous spec if one was present.
4070 -- We know already that the body conforms to that spec. This test is
4071 -- only required for subprograms that come from source.
4073 if Nkind (Parent (N)) = N_Subunit
4074 and then Comes_From_Source (N)
4075 and then not Error_Posted (Body_Id)
4076 and then Nkind (Corresponding_Stub (Parent (N))) =
4077 N_Subprogram_Body_Stub
4080 Old_Id : constant Entity_Id :=
4082 (Specification (Corresponding_Stub (Parent (N))));
4084 Conformant : Boolean := False;
4087 if No (Spec_Id) then
4088 Check_Fully_Conformant (Body_Id, Old_Id);
4092 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4094 if not Conformant then
4096 -- The stub was taken to be a new declaration. Indicate that
4099 Set_Has_Completion (Old_Id, False);
4105 Set_Has_Completion (Body_Id);
4106 Check_Eliminated (Body_Id);
4108 -- Analyze any aspect specifications that appear on the subprogram body
4109 -- stub. Stop the analysis now as the stub does not have a declarative
4110 -- or a statement part, and it cannot be inlined.
4112 if Nkind (N) = N_Subprogram_Body_Stub then
4113 if Has_Aspects (N) then
4114 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4122 -- Note: Normally we don't do any inlining if expansion is off, since
4123 -- we won't generate code in any case. An exception arises in GNATprove
4124 -- mode where we want to expand some calls in place, even with expansion
4125 -- disabled, since the inlining eases formal verification.
4127 if not GNATprove_Mode
4128 and then Expander_Active
4129 and then Serious_Errors_Detected = 0
4130 and then Present (Spec_Id)
4131 and then Has_Pragma_Inline (Spec_Id)
4133 -- Legacy implementation (relying on front-end inlining)
4135 if not Back_End_Inlining then
4136 if (Has_Pragma_Inline_Always (Spec_Id)
4137 and then not Opt.Disable_FE_Inline_Always)
4138 or else (Front_End_Inlining
4139 and then not Opt.Disable_FE_Inline)
4141 Build_Body_To_Inline (N, Spec_Id);
4144 -- New implementation (relying on back-end inlining)
4147 if Has_Pragma_Inline_Always (Spec_Id)
4148 or else Optimization_Level > 0
4150 -- Handle function returning an unconstrained type
4152 if Comes_From_Source (Body_Id)
4153 and then Ekind (Spec_Id) = E_Function
4154 and then Returns_Unconstrained_Type (Spec_Id)
4156 -- If function builds in place, i.e. returns a limited type,
4157 -- inlining cannot be done.
4159 and then not Is_Limited_Type (Etype (Spec_Id))
4161 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4165 Subp_Body : constant Node_Id :=
4166 Unit_Declaration_Node (Body_Id);
4167 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4170 -- Do not pass inlining to the backend if the subprogram
4171 -- has declarations or statements which cannot be inlined
4172 -- by the backend. This check is done here to emit an
4173 -- error instead of the generic warning message reported
4174 -- by the GCC backend (ie. "function might not be
4177 if Present (Subp_Decl)
4178 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4182 elsif Has_Excluded_Statement
4185 (Handled_Statement_Sequence (Subp_Body)))
4189 -- If the backend inlining is available then at this
4190 -- stage we only have to mark the subprogram as inlined.
4191 -- The expander will take care of registering it in the
4192 -- table of subprograms inlined by the backend a part of
4193 -- processing calls to it (cf. Expand_Call)
4196 Set_Is_Inlined (Spec_Id);
4203 -- In GNATprove mode, inline only when there is a separate subprogram
4204 -- declaration for now, as inlining of subprogram bodies acting as
4205 -- declarations, or subprogram stubs, are not supported by front-end
4206 -- inlining. This inlining should occur after analysis of the body, so
4207 -- that it is known whether the value of SPARK_Mode, which can be
4208 -- defined by a pragma inside the body, is applicable to the body.
4209 -- Inlining can be disabled with switch -gnatdm
4211 elsif GNATprove_Mode
4212 and then Full_Analysis
4213 and then not Inside_A_Generic
4214 and then Present (Spec_Id)
4216 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4217 and then Body_Has_SPARK_Mode_On
4218 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4219 and then not Body_Has_Contract
4220 and then not Debug_Flag_M
4222 Build_Body_To_Inline (N, Spec_Id);
4225 -- When generating code, inherited pre/postconditions are handled when
4226 -- expanding the corresponding contract.
4228 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4229 -- of the specification we have to install the private withed units.
4230 -- This holds for child units as well.
4232 if Is_Compilation_Unit (Body_Id)
4233 or else Nkind (Parent (N)) = N_Compilation_Unit
4235 Install_Private_With_Clauses (Body_Id);
4238 Check_Anonymous_Return;
4240 -- Set the Protected_Formal field of each extra formal of the protected
4241 -- subprogram to reference the corresponding extra formal of the
4242 -- subprogram that implements it. For regular formals this occurs when
4243 -- the protected subprogram's declaration is expanded, but the extra
4244 -- formals don't get created until the subprogram is frozen. We need to
4245 -- do this before analyzing the protected subprogram's body so that any
4246 -- references to the original subprogram's extra formals will be changed
4247 -- refer to the implementing subprogram's formals (see Expand_Formal).
4249 if Present (Spec_Id)
4250 and then Is_Protected_Type (Scope (Spec_Id))
4251 and then Present (Protected_Body_Subprogram (Spec_Id))
4254 Impl_Subp : constant Entity_Id :=
4255 Protected_Body_Subprogram (Spec_Id);
4256 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4257 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4260 while Present (Prot_Ext_Formal) loop
4261 pragma Assert (Present (Impl_Ext_Formal));
4262 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4263 Next_Formal_With_Extras (Prot_Ext_Formal);
4264 Next_Formal_With_Extras (Impl_Ext_Formal);
4269 -- Now we can go on to analyze the body
4271 HSS := Handled_Statement_Sequence (N);
4272 Set_Actual_Subtypes (N, Current_Scope);
4274 -- Add a declaration for the Protection object, renaming declarations
4275 -- for discriminals and privals and finally a declaration for the entry
4276 -- family index (if applicable). This form of early expansion is done
4277 -- when the Expander is active because Install_Private_Data_Declarations
4278 -- references entities which were created during regular expansion. The
4279 -- subprogram entity must come from source, and not be an internally
4280 -- generated subprogram.
4283 and then Present (Prot_Typ)
4284 and then Present (Spec_Id)
4285 and then Comes_From_Source (Spec_Id)
4286 and then not Is_Eliminated (Spec_Id)
4288 Install_Private_Data_Declarations
4289 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4292 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4293 -- may now appear in parameter and result profiles. Since the analysis
4294 -- of a subprogram body may use the parameter and result profile of the
4295 -- spec, swap any limited views with their non-limited counterpart.
4297 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4298 Exch_Views := Exchange_Limited_Views (Spec_Id);
4301 -- If the return type is an anonymous access type whose designated type
4302 -- is the limited view of a class-wide type and the non-limited view is
4303 -- available, update the return type accordingly.
4305 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4311 Rtyp := Etype (Spec_Id);
4313 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4314 Etyp := Directly_Designated_Type (Rtyp);
4316 if Is_Class_Wide_Type (Etyp)
4317 and then From_Limited_With (Etyp)
4320 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4326 -- Analyze any aspect specifications that appear on the subprogram body
4328 if Has_Aspects (N) then
4329 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4332 Analyze_Declarations (Declarations (N));
4334 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4336 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4337 if Present (SPARK_Pragma (Spec_Id)) then
4338 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4340 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4342 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4343 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4344 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4346 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4349 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4353 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4354 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4355 Error_Msg_Sloc := Sloc (Spec_Id);
4357 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4361 -- A subprogram body freezes its own contract. Analyze the contract
4362 -- after the declarations of the body have been processed as pragmas
4363 -- are now chained on the contract of the subprogram body.
4365 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4367 -- Check completion, and analyze the statements
4370 Inspect_Deferred_Constant_Completion (Declarations (N));
4373 -- Deal with end of scope processing for the body
4375 Process_End_Label (HSS, 't', Current_Scope);
4376 Update_Use_Clause_Chain;
4379 -- If we are compiling an entry wrapper, remove the enclosing
4380 -- synchronized object from the stack.
4382 if Is_Entry_Wrapper (Body_Id) then
4386 Check_Subprogram_Order (N);
4387 Set_Analyzed (Body_Id);
4389 -- If we have a separate spec, then the analysis of the declarations
4390 -- caused the entities in the body to be chained to the spec id, but
4391 -- we want them chained to the body id. Only the formal parameters
4392 -- end up chained to the spec id in this case.
4394 if Present (Spec_Id) then
4396 -- We must conform to the categorization of our spec
4398 Validate_Categorization_Dependency (N, Spec_Id);
4400 -- And if this is a child unit, the parent units must conform
4402 if Is_Child_Unit (Spec_Id) then
4403 Validate_Categorization_Dependency
4404 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4407 -- Here is where we move entities from the spec to the body
4409 -- Case where there are entities that stay with the spec
4411 if Present (Last_Real_Spec_Entity) then
4413 -- No body entities (happens when the only real spec entities come
4414 -- from precondition and postcondition pragmas).
4416 if No (Last_Entity (Body_Id)) then
4417 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4419 -- Body entities present (formals), so chain stuff past them
4423 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4426 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4427 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4428 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4430 -- Case where there are no spec entities, in this case there can be
4431 -- no body entities either, so just move everything.
4433 -- If the body is generated for an expression function, it may have
4434 -- been preanalyzed already, if 'access was applied to it.
4437 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4438 N_Expression_Function
4440 pragma Assert (No (Last_Entity (Body_Id)));
4444 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4445 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4446 Set_First_Entity (Spec_Id, Empty);
4447 Set_Last_Entity (Spec_Id, Empty);
4451 Check_Missing_Return;
4453 -- Now we are going to check for variables that are never modified in
4454 -- the body of the procedure. But first we deal with a special case
4455 -- where we want to modify this check. If the body of the subprogram
4456 -- starts with a raise statement or its equivalent, or if the body
4457 -- consists entirely of a null statement, then it is pretty obvious that
4458 -- it is OK to not reference the parameters. For example, this might be
4459 -- the following common idiom for a stubbed function: statement of the
4460 -- procedure raises an exception. In particular this deals with the
4461 -- common idiom of a stubbed function, which appears something like:
4463 -- function F (A : Integer) return Some_Type;
4466 -- raise Program_Error;
4470 -- Here the purpose of X is simply to satisfy the annoying requirement
4471 -- in Ada that there be at least one return, and we certainly do not
4472 -- want to go posting warnings on X that it is not initialized. On
4473 -- the other hand, if X is entirely unreferenced that should still
4476 -- What we do is to detect these cases, and if we find them, flag the
4477 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4478 -- suppress unwanted warnings. For the case of the function stub above
4479 -- we have a special test to set X as apparently assigned to suppress
4486 -- Skip call markers installed by the ABE mechanism, labels, and
4487 -- Push_xxx_Error_Label to find the first real statement.
4489 Stm := First (Statements (HSS));
4490 while Nkind_In (Stm, N_Call_Marker, N_Label)
4491 or else Nkind (Stm) in N_Push_xxx_Label
4496 -- Do the test on the original statement before expansion
4499 Ostm : constant Node_Id := Original_Node (Stm);
4502 -- If explicit raise statement, turn on flag
4504 if Nkind (Ostm) = N_Raise_Statement then
4505 Set_Trivial_Subprogram (Stm);
4507 -- If null statement, and no following statements, turn on flag
4509 elsif Nkind (Stm) = N_Null_Statement
4510 and then Comes_From_Source (Stm)
4511 and then No (Next (Stm))
4513 Set_Trivial_Subprogram (Stm);
4515 -- Check for explicit call cases which likely raise an exception
4517 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4518 if Is_Entity_Name (Name (Ostm)) then
4520 Ent : constant Entity_Id := Entity (Name (Ostm));
4523 -- If the procedure is marked No_Return, then likely it
4524 -- raises an exception, but in any case it is not coming
4525 -- back here, so turn on the flag.
4528 and then Ekind (Ent) = E_Procedure
4529 and then No_Return (Ent)
4531 Set_Trivial_Subprogram (Stm);
4539 -- Check for variables that are never modified
4546 -- If there is a separate spec, then transfer Never_Set_In_Source
4547 -- flags from out parameters to the corresponding entities in the
4548 -- body. The reason we do that is we want to post error flags on
4549 -- the body entities, not the spec entities.
4551 if Present (Spec_Id) then
4552 E1 := First_Entity (Spec_Id);
4553 while Present (E1) loop
4554 if Ekind (E1) = E_Out_Parameter then
4555 E2 := First_Entity (Body_Id);
4556 while Present (E2) loop
4557 exit when Chars (E1) = Chars (E2);
4561 if Present (E2) then
4562 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4570 -- Check references in body
4572 Check_References (Body_Id);
4575 -- Check for nested subprogram, and mark outer level subprogram if so
4581 if Present (Spec_Id) then
4588 Ent := Enclosing_Subprogram (Ent);
4589 exit when No (Ent) or else Is_Subprogram (Ent);
4592 if Present (Ent) then
4593 Set_Has_Nested_Subprogram (Ent);
4597 -- Restore the limited views in the spec, if any, to let the back end
4598 -- process it without running into circularities.
4600 if Exch_Views /= No_Elist then
4601 Restore_Limited_Views (Exch_Views);
4604 if Mask_Types /= No_Elist then
4605 Unmask_Unfrozen_Types (Mask_Types);
4608 if Present (Desig_View) then
4609 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4613 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4614 Restore_Ghost_Mode (Saved_GM);
4615 end Analyze_Subprogram_Body_Helper;
4617 ------------------------------------
4618 -- Analyze_Subprogram_Declaration --
4619 ------------------------------------
4621 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4622 Scop : constant Entity_Id := Current_Scope;
4623 Designator : Entity_Id;
4625 Is_Completion : Boolean;
4626 -- Indicates whether a null procedure declaration is a completion
4629 -- Null procedures are not allowed in SPARK
4631 if Nkind (Specification (N)) = N_Procedure_Specification
4632 and then Null_Present (Specification (N))
4634 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4636 -- Null procedures are allowed in protected types, following the
4637 -- recent AI12-0147.
4639 if Is_Protected_Type (Current_Scope)
4640 and then Ada_Version < Ada_2012
4642 Error_Msg_N ("protected operation cannot be a null procedure", N);
4645 Analyze_Null_Procedure (N, Is_Completion);
4647 -- The null procedure acts as a body, nothing further is needed
4649 if Is_Completion then
4654 Designator := Analyze_Subprogram_Specification (Specification (N));
4656 -- A reference may already have been generated for the unit name, in
4657 -- which case the following call is redundant. However it is needed for
4658 -- declarations that are the rewriting of an expression function.
4660 Generate_Definition (Designator);
4662 -- Set the SPARK mode from the current context (may be overwritten later
4663 -- with explicit pragma). This is not done for entry barrier functions
4664 -- because they are generated outside the protected type and should not
4665 -- carry the mode of the enclosing context.
4667 if Nkind (N) = N_Subprogram_Declaration
4668 and then Is_Entry_Barrier_Function (N)
4673 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4674 Set_SPARK_Pragma_Inherited (Designator);
4677 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4678 -- the body of this subprogram is instantiated or inlined later and out
4679 -- of context. The body uses this attribute to restore the value of the
4682 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4683 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4686 -- Preserve relevant elaboration-related attributes of the context which
4687 -- are no longer available or very expensive to recompute once analysis,
4688 -- resolution, and expansion are over.
4690 Mark_Elaboration_Attributes
4691 (N_Id => Designator,
4694 if Debug_Flag_C then
4695 Write_Str ("==> subprogram spec ");
4696 Write_Name (Chars (Designator));
4697 Write_Str (" from ");
4698 Write_Location (Sloc (N));
4703 Validate_RCI_Subprogram_Declaration (N);
4704 New_Overloaded_Entity (Designator);
4705 Check_Delayed_Subprogram (Designator);
4707 -- If the type of the first formal of the current subprogram is a non-
4708 -- generic tagged private type, mark the subprogram as being a private
4709 -- primitive. Ditto if this is a function with controlling result, and
4710 -- the return type is currently private. In both cases, the type of the
4711 -- controlling argument or result must be in the current scope for the
4712 -- operation to be primitive.
4714 if Has_Controlling_Result (Designator)
4715 and then Is_Private_Type (Etype (Designator))
4716 and then Scope (Etype (Designator)) = Current_Scope
4717 and then not Is_Generic_Actual_Type (Etype (Designator))
4719 Set_Is_Private_Primitive (Designator);
4721 elsif Present (First_Formal (Designator)) then
4723 Formal_Typ : constant Entity_Id :=
4724 Etype (First_Formal (Designator));
4726 Set_Is_Private_Primitive (Designator,
4727 Is_Tagged_Type (Formal_Typ)
4728 and then Scope (Formal_Typ) = Current_Scope
4729 and then Is_Private_Type (Formal_Typ)
4730 and then not Is_Generic_Actual_Type (Formal_Typ));
4734 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4737 if Ada_Version >= Ada_2005
4738 and then Comes_From_Source (N)
4739 and then Is_Dispatching_Operation (Designator)
4746 if Has_Controlling_Result (Designator) then
4747 Etyp := Etype (Designator);
4750 E := First_Entity (Designator);
4752 and then Is_Formal (E)
4753 and then not Is_Controlling_Formal (E)
4761 if Is_Access_Type (Etyp) then
4762 Etyp := Directly_Designated_Type (Etyp);
4765 if Is_Interface (Etyp)
4766 and then not Is_Abstract_Subprogram (Designator)
4767 and then not (Ekind (Designator) = E_Procedure
4768 and then Null_Present (Specification (N)))
4770 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4772 -- Specialize error message based on procedures vs. functions,
4773 -- since functions can't be null subprograms.
4775 if Ekind (Designator) = E_Procedure then
4777 ("interface procedure % must be abstract or null", N);
4780 ("interface function % must be abstract", N);
4786 -- What is the following code for, it used to be
4788 -- ??? Set_Suppress_Elaboration_Checks
4789 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4791 -- The following seems equivalent, but a bit dubious
4793 if Elaboration_Checks_Suppressed (Designator) then
4794 Set_Kill_Elaboration_Checks (Designator);
4797 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4798 Set_Categorization_From_Scope (Designator, Scop);
4801 -- For a compilation unit, check for library-unit pragmas
4803 Push_Scope (Designator);
4804 Set_Categorization_From_Pragmas (N);
4805 Validate_Categorization_Dependency (N, Designator);
4809 -- For a compilation unit, set body required. This flag will only be
4810 -- reset if a valid Import or Interface pragma is processed later on.
4812 if Nkind (Parent (N)) = N_Compilation_Unit then
4813 Set_Body_Required (Parent (N), True);
4815 if Ada_Version >= Ada_2005
4816 and then Nkind (Specification (N)) = N_Procedure_Specification
4817 and then Null_Present (Specification (N))
4820 ("null procedure cannot be declared at library level", N);
4824 Generate_Reference_To_Formals (Designator);
4825 Check_Eliminated (Designator);
4827 if Debug_Flag_C then
4829 Write_Str ("<== subprogram spec ");
4830 Write_Name (Chars (Designator));
4831 Write_Str (" from ");
4832 Write_Location (Sloc (N));
4836 if Is_Protected_Type (Current_Scope) then
4838 -- Indicate that this is a protected operation, because it may be
4839 -- used in subsequent declarations within the protected type.
4841 Set_Convention (Designator, Convention_Protected);
4844 List_Inherited_Pre_Post_Aspects (Designator);
4846 if Has_Aspects (N) then
4847 Analyze_Aspect_Specifications (N, Designator);
4849 end Analyze_Subprogram_Declaration;
4851 --------------------------------------
4852 -- Analyze_Subprogram_Specification --
4853 --------------------------------------
4855 -- Reminder: N here really is a subprogram specification (not a subprogram
4856 -- declaration). This procedure is called to analyze the specification in
4857 -- both subprogram bodies and subprogram declarations (specs).
4859 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4860 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4861 -- Determine whether entity E denotes the spec or body of an invariant
4864 ------------------------------------
4865 -- Is_Invariant_Procedure_Or_Body --
4866 ------------------------------------
4868 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4869 Decl : constant Node_Id := Unit_Declaration_Node (E);
4873 if Nkind (Decl) = N_Subprogram_Body then
4874 Spec := Corresponding_Spec (Decl);
4881 and then Ekind (Spec) = E_Procedure
4882 and then (Is_Partial_Invariant_Procedure (Spec)
4883 or else Is_Invariant_Procedure (Spec));
4884 end Is_Invariant_Procedure_Or_Body;
4888 Designator : constant Entity_Id := Defining_Entity (N);
4889 Formals : constant List_Id := Parameter_Specifications (N);
4891 -- Start of processing for Analyze_Subprogram_Specification
4894 -- User-defined operator is not allowed in SPARK, except as a renaming
4896 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4897 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4899 Check_SPARK_05_Restriction
4900 ("user-defined operator is not allowed", N);
4903 -- Proceed with analysis. Do not emit a cross-reference entry if the
4904 -- specification comes from an expression function, because it may be
4905 -- the completion of a previous declaration. If it is not, the cross-
4906 -- reference entry will be emitted for the new subprogram declaration.
4908 if Nkind (Parent (N)) /= N_Expression_Function then
4909 Generate_Definition (Designator);
4912 if Nkind (N) = N_Function_Specification then
4913 Set_Ekind (Designator, E_Function);
4914 Set_Mechanism (Designator, Default_Mechanism);
4916 Set_Ekind (Designator, E_Procedure);
4917 Set_Etype (Designator, Standard_Void_Type);
4920 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4921 -- those subprograms which could be inlined in GNATprove mode (because
4922 -- Body_To_Inline is non-Empty) but should not be inlined.
4924 if GNATprove_Mode then
4925 Set_Is_Inlined_Always (Designator);
4928 -- Introduce new scope for analysis of the formals and the return type
4930 Set_Scope (Designator, Current_Scope);
4932 if Present (Formals) then
4933 Push_Scope (Designator);
4934 Process_Formals (Formals, N);
4936 -- Check dimensions in N for formals with default expression
4938 Analyze_Dimension_Formals (N, Formals);
4940 -- Ada 2005 (AI-345): If this is an overriding operation of an
4941 -- inherited interface operation, and the controlling type is
4942 -- a synchronized type, replace the type with its corresponding
4943 -- record, to match the proper signature of an overriding operation.
4944 -- Same processing for an access parameter whose designated type is
4945 -- derived from a synchronized interface.
4947 -- This modification is not done for invariant procedures because
4948 -- the corresponding record may not necessarely be visible when the
4949 -- concurrent type acts as the full view of a private type.
4952 -- type Prot is private with Type_Invariant => ...;
4953 -- procedure ConcInvariant (Obj : Prot);
4955 -- protected type Prot is ...;
4956 -- type Concurrent_Record_Prot is record ...;
4957 -- procedure ConcInvariant (Obj : Prot) is
4959 -- end ConcInvariant;
4962 -- In the example above, both the spec and body of the invariant
4963 -- procedure must utilize the private type as the controlling type.
4965 if Ada_Version >= Ada_2005
4966 and then not Is_Invariant_Procedure_Or_Body (Designator)
4970 Formal_Typ : Entity_Id;
4971 Rec_Typ : Entity_Id;
4972 Desig_Typ : Entity_Id;
4975 Formal := First_Formal (Designator);
4976 while Present (Formal) loop
4977 Formal_Typ := Etype (Formal);
4979 if Is_Concurrent_Type (Formal_Typ)
4980 and then Present (Corresponding_Record_Type (Formal_Typ))
4982 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
4984 if Present (Interfaces (Rec_Typ)) then
4985 Set_Etype (Formal, Rec_Typ);
4988 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
4989 Desig_Typ := Designated_Type (Formal_Typ);
4991 if Is_Concurrent_Type (Desig_Typ)
4992 and then Present (Corresponding_Record_Type (Desig_Typ))
4994 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
4996 if Present (Interfaces (Rec_Typ)) then
4997 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5002 Next_Formal (Formal);
5009 -- The subprogram scope is pushed and popped around the processing of
5010 -- the return type for consistency with call above to Process_Formals
5011 -- (which itself can call Analyze_Return_Type), and to ensure that any
5012 -- itype created for the return type will be associated with the proper
5015 elsif Nkind (N) = N_Function_Specification then
5016 Push_Scope (Designator);
5017 Analyze_Return_Type (N);
5023 if Nkind (N) = N_Function_Specification then
5025 -- Deal with operator symbol case
5027 if Nkind (Designator) = N_Defining_Operator_Symbol then
5028 Valid_Operator_Definition (Designator);
5031 May_Need_Actuals (Designator);
5033 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5034 -- the subprogram is abstract also. This does not apply to renaming
5035 -- declarations, where abstractness is inherited, and to subprogram
5036 -- bodies generated for stream operations, which become renamings as
5039 -- In case of primitives associated with abstract interface types
5040 -- the check is applied later (see Analyze_Subprogram_Declaration).
5042 if not Nkind_In (Original_Node (Parent (N)),
5043 N_Abstract_Subprogram_Declaration,
5044 N_Formal_Abstract_Subprogram_Declaration,
5045 N_Subprogram_Renaming_Declaration)
5047 if Is_Abstract_Type (Etype (Designator))
5048 and then not Is_Interface (Etype (Designator))
5051 ("function that returns abstract type must be abstract", N);
5053 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5054 -- access result whose designated type is abstract.
5056 elsif Ada_Version >= Ada_2012
5057 and then Nkind (Result_Definition (N)) = N_Access_Definition
5059 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5060 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5063 ("function whose access result designates abstract type "
5064 & "must be abstract", N);
5070 end Analyze_Subprogram_Specification;
5072 -----------------------
5073 -- Check_Conformance --
5074 -----------------------
5076 procedure Check_Conformance
5077 (New_Id : Entity_Id;
5079 Ctype : Conformance_Type;
5081 Conforms : out Boolean;
5082 Err_Loc : Node_Id := Empty;
5083 Get_Inst : Boolean := False;
5084 Skip_Controlling_Formals : Boolean := False)
5086 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5087 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5088 -- If Errmsg is True, then processing continues to post an error message
5089 -- for conformance error on given node. Two messages are output. The
5090 -- first message points to the previous declaration with a general "no
5091 -- conformance" message. The second is the detailed reason, supplied as
5092 -- Msg. The parameter N provide information for a possible & insertion
5093 -- in the message, and also provides the location for posting the
5094 -- message in the absence of a specified Err_Loc location.
5096 function Conventions_Match
5098 Id2 : Entity_Id) return Boolean;
5099 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5102 -----------------------
5103 -- Conformance_Error --
5104 -----------------------
5106 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5113 if No (Err_Loc) then
5119 Error_Msg_Sloc := Sloc (Old_Id);
5122 when Type_Conformant =>
5123 Error_Msg_N -- CODEFIX
5124 ("not type conformant with declaration#!", Enode);
5126 when Mode_Conformant =>
5127 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5129 ("not mode conformant with operation inherited#!",
5133 ("not mode conformant with declaration#!", Enode);
5136 when Subtype_Conformant =>
5137 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5139 ("not subtype conformant with operation inherited#!",
5143 ("not subtype conformant with declaration#!", Enode);
5146 when Fully_Conformant =>
5147 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5148 Error_Msg_N -- CODEFIX
5149 ("not fully conformant with operation inherited#!",
5152 Error_Msg_N -- CODEFIX
5153 ("not fully conformant with declaration#!", Enode);
5157 Error_Msg_NE (Msg, Enode, N);
5159 end Conformance_Error;
5161 -----------------------
5162 -- Conventions_Match --
5163 -----------------------
5165 function Conventions_Match
5167 Id2 : Entity_Id) return Boolean
5170 -- Ignore the conventions of anonymous access-to-subprogram types
5171 -- and subprogram types because these are internally generated and
5172 -- the only way these may receive a convention is if they inherit
5173 -- the convention of a related subprogram.
5175 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5178 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5183 -- Otherwise compare the conventions directly
5186 return Convention (Id1) = Convention (Id2);
5188 end Conventions_Match;
5192 Old_Type : constant Entity_Id := Etype (Old_Id);
5193 New_Type : constant Entity_Id := Etype (New_Id);
5194 Old_Formal : Entity_Id;
5195 New_Formal : Entity_Id;
5196 Access_Types_Match : Boolean;
5197 Old_Formal_Base : Entity_Id;
5198 New_Formal_Base : Entity_Id;
5200 -- Start of processing for Check_Conformance
5205 -- We need a special case for operators, since they don't appear
5208 if Ctype = Type_Conformant then
5209 if Ekind (New_Id) = E_Operator
5210 and then Operator_Matches_Spec (New_Id, Old_Id)
5216 -- If both are functions/operators, check return types conform
5218 if Old_Type /= Standard_Void_Type
5220 New_Type /= Standard_Void_Type
5222 -- If we are checking interface conformance we omit controlling
5223 -- arguments and result, because we are only checking the conformance
5224 -- of the remaining parameters.
5226 if Has_Controlling_Result (Old_Id)
5227 and then Has_Controlling_Result (New_Id)
5228 and then Skip_Controlling_Formals
5232 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5233 if Ctype >= Subtype_Conformant
5234 and then not Predicates_Match (Old_Type, New_Type)
5237 ("\predicate of return type does not match!", New_Id);
5240 ("\return type does not match!", New_Id);
5246 -- Ada 2005 (AI-231): In case of anonymous access types check the
5247 -- null-exclusion and access-to-constant attributes match.
5249 if Ada_Version >= Ada_2005
5250 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5252 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5253 or else Is_Access_Constant (Etype (Old_Type)) /=
5254 Is_Access_Constant (Etype (New_Type)))
5256 Conformance_Error ("\return type does not match!", New_Id);
5260 -- If either is a function/operator and the other isn't, error
5262 elsif Old_Type /= Standard_Void_Type
5263 or else New_Type /= Standard_Void_Type
5265 Conformance_Error ("\functions can only match functions!", New_Id);
5269 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5270 -- If this is a renaming as body, refine error message to indicate that
5271 -- the conflict is with the original declaration. If the entity is not
5272 -- frozen, the conventions don't have to match, the one of the renamed
5273 -- entity is inherited.
5275 if Ctype >= Subtype_Conformant then
5276 if not Conventions_Match (Old_Id, New_Id) then
5277 if not Is_Frozen (New_Id) then
5280 elsif Present (Err_Loc)
5281 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5282 and then Present (Corresponding_Spec (Err_Loc))
5284 Error_Msg_Name_1 := Chars (New_Id);
5286 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5287 Conformance_Error ("\prior declaration for% has convention %!");
5290 Conformance_Error ("\calling conventions do not match!");
5295 elsif Is_Formal_Subprogram (Old_Id)
5296 or else Is_Formal_Subprogram (New_Id)
5298 Conformance_Error ("\formal subprograms not allowed!");
5303 -- Deal with parameters
5305 -- Note: we use the entity information, rather than going directly
5306 -- to the specification in the tree. This is not only simpler, but
5307 -- absolutely necessary for some cases of conformance tests between
5308 -- operators, where the declaration tree simply does not exist.
5310 Old_Formal := First_Formal (Old_Id);
5311 New_Formal := First_Formal (New_Id);
5312 while Present (Old_Formal) and then Present (New_Formal) loop
5313 if Is_Controlling_Formal (Old_Formal)
5314 and then Is_Controlling_Formal (New_Formal)
5315 and then Skip_Controlling_Formals
5317 -- The controlling formals will have different types when
5318 -- comparing an interface operation with its match, but both
5319 -- or neither must be access parameters.
5321 if Is_Access_Type (Etype (Old_Formal))
5323 Is_Access_Type (Etype (New_Formal))
5325 goto Skip_Controlling_Formal;
5328 ("\access parameter does not match!", New_Formal);
5332 -- Ada 2012: Mode conformance also requires that formal parameters
5333 -- be both aliased, or neither.
5335 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5336 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5338 ("\aliased parameter mismatch!", New_Formal);
5342 if Ctype = Fully_Conformant then
5344 -- Names must match. Error message is more accurate if we do
5345 -- this before checking that the types of the formals match.
5347 if Chars (Old_Formal) /= Chars (New_Formal) then
5348 Conformance_Error ("\name& does not match!", New_Formal);
5350 -- Set error posted flag on new formal as well to stop
5351 -- junk cascaded messages in some cases.
5353 Set_Error_Posted (New_Formal);
5357 -- Null exclusion must match
5359 if Null_Exclusion_Present (Parent (Old_Formal))
5361 Null_Exclusion_Present (Parent (New_Formal))
5363 -- Only give error if both come from source. This should be
5364 -- investigated some time, since it should not be needed ???
5366 if Comes_From_Source (Old_Formal)
5368 Comes_From_Source (New_Formal)
5371 ("\null exclusion for& does not match", New_Formal);
5373 -- Mark error posted on the new formal to avoid duplicated
5374 -- complaint about types not matching.
5376 Set_Error_Posted (New_Formal);
5381 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5382 -- case occurs whenever a subprogram is being renamed and one of its
5383 -- parameters imposes a null exclusion. For example:
5385 -- type T is null record;
5386 -- type Acc_T is access T;
5387 -- subtype Acc_T_Sub is Acc_T;
5389 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5390 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5393 Old_Formal_Base := Etype (Old_Formal);
5394 New_Formal_Base := Etype (New_Formal);
5397 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5398 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5401 Access_Types_Match := Ada_Version >= Ada_2005
5403 -- Ensure that this rule is only applied when New_Id is a
5404 -- renaming of Old_Id.
5406 and then Nkind (Parent (Parent (New_Id))) =
5407 N_Subprogram_Renaming_Declaration
5408 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5409 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5410 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5412 -- Now handle the allowed access-type case
5414 and then Is_Access_Type (Old_Formal_Base)
5415 and then Is_Access_Type (New_Formal_Base)
5417 -- The type kinds must match. The only exception occurs with
5418 -- multiple generics of the form:
5421 -- type F is private; type A is private;
5422 -- type F_Ptr is access F; type A_Ptr is access A;
5423 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5424 -- package F_Pack is ... package A_Pack is
5425 -- package F_Inst is
5426 -- new F_Pack (A, A_Ptr, A_P);
5428 -- When checking for conformance between the parameters of A_P
5429 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5430 -- because the compiler has transformed A_Ptr into a subtype of
5431 -- F_Ptr. We catch this case in the code below.
5433 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5435 (Is_Generic_Type (Old_Formal_Base)
5436 and then Is_Generic_Type (New_Formal_Base)
5437 and then Is_Internal (New_Formal_Base)
5438 and then Etype (Etype (New_Formal_Base)) =
5440 and then Directly_Designated_Type (Old_Formal_Base) =
5441 Directly_Designated_Type (New_Formal_Base)
5442 and then ((Is_Itype (Old_Formal_Base)
5443 and then Can_Never_Be_Null (Old_Formal_Base))
5445 (Is_Itype (New_Formal_Base)
5446 and then Can_Never_Be_Null (New_Formal_Base)));
5448 -- Types must always match. In the visible part of an instance,
5449 -- usual overloading rules for dispatching operations apply, and
5450 -- we check base types (not the actual subtypes).
5452 if In_Instance_Visible_Part
5453 and then Is_Dispatching_Operation (New_Id)
5455 if not Conforming_Types
5456 (T1 => Base_Type (Etype (Old_Formal)),
5457 T2 => Base_Type (Etype (New_Formal)),
5459 Get_Inst => Get_Inst)
5460 and then not Access_Types_Match
5462 Conformance_Error ("\type of & does not match!", New_Formal);
5466 elsif not Conforming_Types
5467 (T1 => Old_Formal_Base,
5468 T2 => New_Formal_Base,
5470 Get_Inst => Get_Inst)
5471 and then not Access_Types_Match
5473 -- Don't give error message if old type is Any_Type. This test
5474 -- avoids some cascaded errors, e.g. in case of a bad spec.
5476 if Errmsg and then Old_Formal_Base = Any_Type then
5479 if Ctype >= Subtype_Conformant
5481 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5484 ("\predicate of & does not match!", New_Formal);
5487 ("\type of & does not match!", New_Formal);
5489 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5491 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5499 -- For mode conformance, mode must match
5501 if Ctype >= Mode_Conformant then
5502 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5503 if not Ekind_In (New_Id, E_Function, E_Procedure)
5504 or else not Is_Primitive_Wrapper (New_Id)
5506 Conformance_Error ("\mode of & does not match!", New_Formal);
5510 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5512 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5514 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5517 ("\mode of & does not match!", New_Formal);
5524 -- Part of mode conformance for access types is having the same
5525 -- constant modifier.
5527 elsif Access_Types_Match
5528 and then Is_Access_Constant (Old_Formal_Base) /=
5529 Is_Access_Constant (New_Formal_Base)
5532 ("\constant modifier does not match!", New_Formal);
5537 if Ctype >= Subtype_Conformant then
5539 -- Ada 2005 (AI-231): In case of anonymous access types check
5540 -- the null-exclusion and access-to-constant attributes must
5541 -- match. For null exclusion, we test the types rather than the
5542 -- formals themselves, since the attribute is only set reliably
5543 -- on the formals in the Ada 95 case, and we exclude the case
5544 -- where Old_Formal is marked as controlling, to avoid errors
5545 -- when matching completing bodies with dispatching declarations
5546 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5548 if Ada_Version >= Ada_2005
5549 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5550 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5552 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5553 Can_Never_Be_Null (Etype (New_Formal))
5555 not Is_Controlling_Formal (Old_Formal))
5557 Is_Access_Constant (Etype (Old_Formal)) /=
5558 Is_Access_Constant (Etype (New_Formal)))
5560 -- Do not complain if error already posted on New_Formal. This
5561 -- avoids some redundant error messages.
5563 and then not Error_Posted (New_Formal)
5565 -- It is allowed to omit the null-exclusion in case of stream
5566 -- attribute subprograms. We recognize stream subprograms
5567 -- through their TSS-generated suffix.
5570 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5573 if TSS_Name /= TSS_Stream_Read
5574 and then TSS_Name /= TSS_Stream_Write
5575 and then TSS_Name /= TSS_Stream_Input
5576 and then TSS_Name /= TSS_Stream_Output
5578 -- Here we have a definite conformance error. It is worth
5579 -- special casing the error message for the case of a
5580 -- controlling formal (which excludes null).
5582 if Is_Controlling_Formal (New_Formal) then
5583 Error_Msg_Node_2 := Scope (New_Formal);
5585 ("\controlling formal & of & excludes null, "
5586 & "declaration must exclude null as well",
5589 -- Normal case (couldn't we give more detail here???)
5593 ("\type of & does not match!", New_Formal);
5602 -- Full conformance checks
5604 if Ctype = Fully_Conformant then
5606 -- We have checked already that names match
5608 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5610 -- Check default expressions for in parameters
5613 NewD : constant Boolean :=
5614 Present (Default_Value (New_Formal));
5615 OldD : constant Boolean :=
5616 Present (Default_Value (Old_Formal));
5618 if NewD or OldD then
5620 -- The old default value has been analyzed because the
5621 -- current full declaration will have frozen everything
5622 -- before. The new default value has not been analyzed,
5623 -- so analyze it now before we check for conformance.
5626 Push_Scope (New_Id);
5627 Preanalyze_Spec_Expression
5628 (Default_Value (New_Formal), Etype (New_Formal));
5632 if not (NewD and OldD)
5633 or else not Fully_Conformant_Expressions
5634 (Default_Value (Old_Formal),
5635 Default_Value (New_Formal))
5638 ("\default expression for & does not match!",
5647 -- A couple of special checks for Ada 83 mode. These checks are
5648 -- skipped if either entity is an operator in package Standard,
5649 -- or if either old or new instance is not from the source program.
5651 if Ada_Version = Ada_83
5652 and then Sloc (Old_Id) > Standard_Location
5653 and then Sloc (New_Id) > Standard_Location
5654 and then Comes_From_Source (Old_Id)
5655 and then Comes_From_Source (New_Id)
5658 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5659 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5662 -- Explicit IN must be present or absent in both cases. This
5663 -- test is required only in the full conformance case.
5665 if In_Present (Old_Param) /= In_Present (New_Param)
5666 and then Ctype = Fully_Conformant
5669 ("\(Ada 83) IN must appear in both declarations",
5674 -- Grouping (use of comma in param lists) must be the same
5675 -- This is where we catch a misconformance like:
5678 -- A : Integer; B : Integer
5680 -- which are represented identically in the tree except
5681 -- for the setting of the flags More_Ids and Prev_Ids.
5683 if More_Ids (Old_Param) /= More_Ids (New_Param)
5684 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5687 ("\grouping of & does not match!", New_Formal);
5693 -- This label is required when skipping controlling formals
5695 <<Skip_Controlling_Formal>>
5697 Next_Formal (Old_Formal);
5698 Next_Formal (New_Formal);
5701 if Present (Old_Formal) then
5702 Conformance_Error ("\too few parameters!");
5705 elsif Present (New_Formal) then
5706 Conformance_Error ("\too many parameters!", New_Formal);
5709 end Check_Conformance;
5711 -----------------------
5712 -- Check_Conventions --
5713 -----------------------
5715 procedure Check_Conventions (Typ : Entity_Id) is
5716 Ifaces_List : Elist_Id;
5718 procedure Check_Convention (Op : Entity_Id);
5719 -- Verify that the convention of inherited dispatching operation Op is
5720 -- consistent among all subprograms it overrides. In order to minimize
5721 -- the search, Search_From is utilized to designate a specific point in
5722 -- the list rather than iterating over the whole list once more.
5724 ----------------------
5725 -- Check_Convention --
5726 ----------------------
5728 procedure Check_Convention (Op : Entity_Id) is
5729 Op_Conv : constant Convention_Id := Convention (Op);
5730 Iface_Conv : Convention_Id;
5731 Iface_Elmt : Elmt_Id;
5732 Iface_Prim_Elmt : Elmt_Id;
5733 Iface_Prim : Entity_Id;
5736 Iface_Elmt := First_Elmt (Ifaces_List);
5737 while Present (Iface_Elmt) loop
5739 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5740 while Present (Iface_Prim_Elmt) loop
5741 Iface_Prim := Node (Iface_Prim_Elmt);
5742 Iface_Conv := Convention (Iface_Prim);
5744 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5745 and then Iface_Conv /= Op_Conv
5748 ("inconsistent conventions in primitive operations", Typ);
5750 Error_Msg_Name_1 := Chars (Op);
5751 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5752 Error_Msg_Sloc := Sloc (Op);
5754 if Comes_From_Source (Op) or else No (Alias (Op)) then
5755 if not Present (Overridden_Operation (Op)) then
5756 Error_Msg_N ("\\primitive % defined #", Typ);
5759 ("\\overriding operation % with "
5760 & "convention % defined #", Typ);
5763 else pragma Assert (Present (Alias (Op)));
5764 Error_Msg_Sloc := Sloc (Alias (Op));
5765 Error_Msg_N ("\\inherited operation % with "
5766 & "convention % defined #", Typ);
5769 Error_Msg_Name_1 := Chars (Op);
5770 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5771 Error_Msg_Sloc := Sloc (Iface_Prim);
5772 Error_Msg_N ("\\overridden operation % with "
5773 & "convention % defined #", Typ);
5775 -- Avoid cascading errors
5780 Next_Elmt (Iface_Prim_Elmt);
5783 Next_Elmt (Iface_Elmt);
5785 end Check_Convention;
5789 Prim_Op : Entity_Id;
5790 Prim_Op_Elmt : Elmt_Id;
5792 -- Start of processing for Check_Conventions
5795 if not Has_Interfaces (Typ) then
5799 Collect_Interfaces (Typ, Ifaces_List);
5801 -- The algorithm checks every overriding dispatching operation against
5802 -- all the corresponding overridden dispatching operations, detecting
5803 -- differences in conventions.
5805 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5806 while Present (Prim_Op_Elmt) loop
5807 Prim_Op := Node (Prim_Op_Elmt);
5809 -- A small optimization: skip the predefined dispatching operations
5810 -- since they always have the same convention.
5812 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5813 Check_Convention (Prim_Op);
5816 Next_Elmt (Prim_Op_Elmt);
5818 end Check_Conventions;
5820 ------------------------------
5821 -- Check_Delayed_Subprogram --
5822 ------------------------------
5824 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5827 procedure Possible_Freeze (T : Entity_Id);
5828 -- T is the type of either a formal parameter or of the return type.
5829 -- If T is not yet frozen and needs a delayed freeze, then the
5830 -- subprogram itself must be delayed.
5832 ---------------------
5833 -- Possible_Freeze --
5834 ---------------------
5836 procedure Possible_Freeze (T : Entity_Id) is
5837 Scop : constant Entity_Id := Scope (Designator);
5839 -- If the subprogram appears within a package instance (which
5840 -- may be the wrapper package of a subprogram instance) the
5841 -- freeze node for that package will freeze the subprogram at
5842 -- the proper place, so do not emit a freeze node for the
5843 -- subprogram, given that it may appear in the wrong scope.
5845 if Ekind (Scop) = E_Package
5846 and then not Comes_From_Source (Scop)
5847 and then Is_Generic_Instance (Scop)
5851 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5852 Set_Has_Delayed_Freeze (Designator);
5854 elsif Is_Access_Type (T)
5855 and then Has_Delayed_Freeze (Designated_Type (T))
5856 and then not Is_Frozen (Designated_Type (T))
5858 Set_Has_Delayed_Freeze (Designator);
5861 end Possible_Freeze;
5863 -- Start of processing for Check_Delayed_Subprogram
5866 -- All subprograms, including abstract subprograms, may need a freeze
5867 -- node if some formal type or the return type needs one.
5869 Possible_Freeze (Etype (Designator));
5870 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5872 -- Need delayed freeze if any of the formal types themselves need
5873 -- a delayed freeze and are not yet frozen.
5875 F := First_Formal (Designator);
5876 while Present (F) loop
5877 Possible_Freeze (Etype (F));
5878 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5882 -- Mark functions that return by reference. Note that it cannot be
5883 -- done for delayed_freeze subprograms because the underlying
5884 -- returned type may not be known yet (for private types)
5886 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5888 Typ : constant Entity_Id := Etype (Designator);
5889 Utyp : constant Entity_Id := Underlying_Type (Typ);
5891 if Is_Limited_View (Typ) then
5892 Set_Returns_By_Ref (Designator);
5893 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5894 Set_Returns_By_Ref (Designator);
5898 end Check_Delayed_Subprogram;
5900 ------------------------------------
5901 -- Check_Discriminant_Conformance --
5902 ------------------------------------
5904 procedure Check_Discriminant_Conformance
5909 Old_Discr : Entity_Id := First_Discriminant (Prev);
5910 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5911 New_Discr_Id : Entity_Id;
5912 New_Discr_Type : Entity_Id;
5914 procedure Conformance_Error (Msg : String; N : Node_Id);
5915 -- Post error message for conformance error on given node. Two messages
5916 -- are output. The first points to the previous declaration with a
5917 -- general "no conformance" message. The second is the detailed reason,
5918 -- supplied as Msg. The parameter N provide information for a possible
5919 -- & insertion in the message.
5921 -----------------------
5922 -- Conformance_Error --
5923 -----------------------
5925 procedure Conformance_Error (Msg : String; N : Node_Id) is
5927 Error_Msg_Sloc := Sloc (Prev_Loc);
5928 Error_Msg_N -- CODEFIX
5929 ("not fully conformant with declaration#!", N);
5930 Error_Msg_NE (Msg, N, N);
5931 end Conformance_Error;
5933 -- Start of processing for Check_Discriminant_Conformance
5936 while Present (Old_Discr) and then Present (New_Discr) loop
5937 New_Discr_Id := Defining_Identifier (New_Discr);
5939 -- The subtype mark of the discriminant on the full type has not
5940 -- been analyzed so we do it here. For an access discriminant a new
5943 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5945 Access_Definition (N, Discriminant_Type (New_Discr));
5948 Analyze (Discriminant_Type (New_Discr));
5949 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5951 -- Ada 2005: if the discriminant definition carries a null
5952 -- exclusion, create an itype to check properly for consistency
5953 -- with partial declaration.
5955 if Is_Access_Type (New_Discr_Type)
5956 and then Null_Exclusion_Present (New_Discr)
5959 Create_Null_Excluding_Itype
5960 (T => New_Discr_Type,
5961 Related_Nod => New_Discr,
5962 Scope_Id => Current_Scope);
5966 if not Conforming_Types
5967 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5969 Conformance_Error ("type of & does not match!", New_Discr_Id);
5972 -- Treat the new discriminant as an occurrence of the old one,
5973 -- for navigation purposes, and fill in some semantic
5974 -- information, for completeness.
5976 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5977 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5978 Set_Scope (New_Discr_Id, Scope (Old_Discr));
5983 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
5984 Conformance_Error ("name & does not match!", New_Discr_Id);
5988 -- Default expressions must match
5991 NewD : constant Boolean :=
5992 Present (Expression (New_Discr));
5993 OldD : constant Boolean :=
5994 Present (Expression (Parent (Old_Discr)));
5997 if NewD or OldD then
5999 -- The old default value has been analyzed and expanded,
6000 -- because the current full declaration will have frozen
6001 -- everything before. The new default values have not been
6002 -- expanded, so expand now to check conformance.
6005 Preanalyze_Spec_Expression
6006 (Expression (New_Discr), New_Discr_Type);
6009 if not (NewD and OldD)
6010 or else not Fully_Conformant_Expressions
6011 (Expression (Parent (Old_Discr)),
6012 Expression (New_Discr))
6016 ("default expression for & does not match!",
6023 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6025 if Ada_Version = Ada_83 then
6027 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6030 -- Grouping (use of comma in param lists) must be the same
6031 -- This is where we catch a misconformance like:
6034 -- A : Integer; B : Integer
6036 -- which are represented identically in the tree except
6037 -- for the setting of the flags More_Ids and Prev_Ids.
6039 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6040 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6043 ("grouping of & does not match!", New_Discr_Id);
6049 Next_Discriminant (Old_Discr);
6053 if Present (Old_Discr) then
6054 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6057 elsif Present (New_Discr) then
6059 ("too many discriminants!", Defining_Identifier (New_Discr));
6062 end Check_Discriminant_Conformance;
6064 ----------------------------
6065 -- Check_Fully_Conformant --
6066 ----------------------------
6068 procedure Check_Fully_Conformant
6069 (New_Id : Entity_Id;
6071 Err_Loc : Node_Id := Empty)
6074 pragma Warnings (Off, Result);
6077 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6078 end Check_Fully_Conformant;
6080 --------------------------
6081 -- Check_Limited_Return --
6082 --------------------------
6084 procedure Check_Limited_Return
6090 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6091 -- replaced by anonymous access results. This is an incompatibility with
6092 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6093 -- controllable with special switch. ???
6095 -- A limited interface that is not immutably limited is OK
6097 if Is_Limited_Interface (R_Type)
6099 not (Is_Task_Interface (R_Type)
6100 or else Is_Protected_Interface (R_Type)
6101 or else Is_Synchronized_Interface (R_Type))
6105 elsif Is_Limited_Type (R_Type)
6106 and then not Is_Interface (R_Type)
6107 and then Comes_From_Source (N)
6108 and then not In_Instance_Body
6109 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6111 -- Error in Ada 2005
6113 if Ada_Version >= Ada_2005
6114 and then not Debug_Flag_Dot_L
6115 and then not GNAT_Mode
6118 ("(Ada 2005) cannot copy object of a limited type "
6119 & "(RM-2005 6.5(5.5/2))", Expr);
6121 if Is_Limited_View (R_Type) then
6123 ("\return by reference not permitted in Ada 2005", Expr);
6126 -- Warn in Ada 95 mode, to give folks a heads up about this
6129 -- In GNAT mode, this is just a warning, to allow it to be evilly
6130 -- turned off. Otherwise it is a real error.
6132 -- In a generic context, simplify the warning because it makes no
6133 -- sense to discuss pass-by-reference or copy.
6135 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6136 if Inside_A_Generic then
6138 ("return of limited object not permitted in Ada 2005 "
6139 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6141 elsif Is_Limited_View (R_Type) then
6143 ("return by reference not permitted in Ada 2005 "
6144 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6147 ("cannot copy object of a limited type in Ada 2005 "
6148 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6151 -- Ada 95 mode, and compatibility warnings disabled
6154 pragma Assert (Ada_Version <= Ada_95);
6155 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6156 return; -- skip continuation messages below
6159 if not Inside_A_Generic then
6161 ("\consider switching to return of access type", Expr);
6162 Explain_Limited_Type (R_Type, Expr);
6165 end Check_Limited_Return;
6167 ---------------------------
6168 -- Check_Mode_Conformant --
6169 ---------------------------
6171 procedure Check_Mode_Conformant
6172 (New_Id : Entity_Id;
6174 Err_Loc : Node_Id := Empty;
6175 Get_Inst : Boolean := False)
6178 pragma Warnings (Off, Result);
6181 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6182 end Check_Mode_Conformant;
6184 --------------------------------
6185 -- Check_Overriding_Indicator --
6186 --------------------------------
6188 procedure Check_Overriding_Indicator
6190 Overridden_Subp : Entity_Id;
6191 Is_Primitive : Boolean)
6197 -- No overriding indicator for literals
6199 if Ekind (Subp) = E_Enumeration_Literal then
6202 elsif Ekind (Subp) = E_Entry then
6203 Decl := Parent (Subp);
6205 -- No point in analyzing a malformed operator
6207 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6208 and then Error_Posted (Subp)
6213 Decl := Unit_Declaration_Node (Subp);
6216 if Nkind_In (Decl, N_Subprogram_Body,
6217 N_Subprogram_Body_Stub,
6218 N_Subprogram_Declaration,
6219 N_Abstract_Subprogram_Declaration,
6220 N_Subprogram_Renaming_Declaration)
6222 Spec := Specification (Decl);
6224 elsif Nkind (Decl) = N_Entry_Declaration then
6231 -- The overriding operation is type conformant with the overridden one,
6232 -- but the names of the formals are not required to match. If the names
6233 -- appear permuted in the overriding operation, this is a possible
6234 -- source of confusion that is worth diagnosing. Controlling formals
6235 -- often carry names that reflect the type, and it is not worthwhile
6236 -- requiring that their names match.
6238 if Present (Overridden_Subp)
6239 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6246 Form1 := First_Formal (Subp);
6247 Form2 := First_Formal (Overridden_Subp);
6249 -- If the overriding operation is a synchronized operation, skip
6250 -- the first parameter of the overridden operation, which is
6251 -- implicit in the new one. If the operation is declared in the
6252 -- body it is not primitive and all formals must match.
6254 if Is_Concurrent_Type (Scope (Subp))
6255 and then Is_Tagged_Type (Scope (Subp))
6256 and then not Has_Completion (Scope (Subp))
6258 Form2 := Next_Formal (Form2);
6261 if Present (Form1) then
6262 Form1 := Next_Formal (Form1);
6263 Form2 := Next_Formal (Form2);
6266 while Present (Form1) loop
6267 if not Is_Controlling_Formal (Form1)
6268 and then Present (Next_Formal (Form2))
6269 and then Chars (Form1) = Chars (Next_Formal (Form2))
6271 Error_Msg_Node_2 := Alias (Overridden_Subp);
6272 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6274 ("& does not match corresponding formal of&#",
6279 Next_Formal (Form1);
6280 Next_Formal (Form2);
6285 -- If there is an overridden subprogram, then check that there is no
6286 -- "not overriding" indicator, and mark the subprogram as overriding.
6287 -- This is not done if the overridden subprogram is marked as hidden,
6288 -- which can occur for the case of inherited controlled operations
6289 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6290 -- subprogram is not itself hidden. (Note: This condition could probably
6291 -- be simplified, leaving out the testing for the specific controlled
6292 -- cases, but it seems safer and clearer this way, and echoes similar
6293 -- special-case tests of this kind in other places.)
6295 if Present (Overridden_Subp)
6296 and then (not Is_Hidden (Overridden_Subp)
6298 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6301 and then Present (Alias (Overridden_Subp))
6302 and then not Is_Hidden (Alias (Overridden_Subp))))
6304 if Must_Not_Override (Spec) then
6305 Error_Msg_Sloc := Sloc (Overridden_Subp);
6307 if Ekind (Subp) = E_Entry then
6309 ("entry & overrides inherited operation #", Spec, Subp);
6312 ("subprogram & overrides inherited operation #", Spec, Subp);
6315 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6316 -- as an extension of Root_Controlled, and thus has a useless Adjust
6317 -- operation. This operation should not be inherited by other limited
6318 -- controlled types. An explicit Adjust for them is not overriding.
6320 elsif Must_Override (Spec)
6321 and then Chars (Overridden_Subp) = Name_Adjust
6322 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6323 and then Present (Alias (Overridden_Subp))
6324 and then In_Predefined_Unit (Alias (Overridden_Subp))
6327 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6328 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6330 elsif Is_Subprogram (Subp) then
6331 if Is_Init_Proc (Subp) then
6334 elsif No (Overridden_Operation (Subp)) then
6336 -- For entities generated by Derive_Subprograms the overridden
6337 -- operation is the inherited primitive (which is available
6338 -- through the attribute alias)
6340 if (Is_Dispatching_Operation (Subp)
6341 or else Is_Dispatching_Operation (Overridden_Subp))
6342 and then not Comes_From_Source (Overridden_Subp)
6343 and then Find_Dispatching_Type (Overridden_Subp) =
6344 Find_Dispatching_Type (Subp)
6345 and then Present (Alias (Overridden_Subp))
6346 and then Comes_From_Source (Alias (Overridden_Subp))
6348 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6349 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6352 Set_Overridden_Operation (Subp, Overridden_Subp);
6353 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6358 -- If primitive flag is set or this is a protected operation, then
6359 -- the operation is overriding at the point of its declaration, so
6360 -- warn if necessary. Otherwise it may have been declared before the
6361 -- operation it overrides and no check is required.
6364 and then not Must_Override (Spec)
6365 and then (Is_Primitive
6366 or else Ekind (Scope (Subp)) = E_Protected_Type)
6368 Style.Missing_Overriding (Decl, Subp);
6371 -- If Subp is an operator, it may override a predefined operation, if
6372 -- it is defined in the same scope as the type to which it applies.
6373 -- In that case Overridden_Subp is empty because of our implicit
6374 -- representation for predefined operators. We have to check whether the
6375 -- signature of Subp matches that of a predefined operator. Note that
6376 -- first argument provides the name of the operator, and the second
6377 -- argument the signature that may match that of a standard operation.
6378 -- If the indicator is overriding, then the operator must match a
6379 -- predefined signature, because we know already that there is no
6380 -- explicit overridden operation.
6382 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6383 if Must_Not_Override (Spec) then
6385 -- If this is not a primitive or a protected subprogram, then
6386 -- "not overriding" is illegal.
6389 and then Ekind (Scope (Subp)) /= E_Protected_Type
6391 Error_Msg_N ("overriding indicator only allowed "
6392 & "if subprogram is primitive", Subp);
6394 elsif Can_Override_Operator (Subp) then
6396 ("subprogram& overrides predefined operator ", Spec, Subp);
6399 elsif Must_Override (Spec) then
6400 if No (Overridden_Operation (Subp))
6401 and then not Can_Override_Operator (Subp)
6403 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6406 elsif not Error_Posted (Subp)
6407 and then Style_Check
6408 and then Can_Override_Operator (Subp)
6409 and then not In_Predefined_Unit (Subp)
6411 -- If style checks are enabled, indicate that the indicator is
6412 -- missing. However, at the point of declaration, the type of
6413 -- which this is a primitive operation may be private, in which
6414 -- case the indicator would be premature.
6416 if Has_Private_Declaration (Etype (Subp))
6417 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6421 Style.Missing_Overriding (Decl, Subp);
6425 elsif Must_Override (Spec) then
6426 if Ekind (Subp) = E_Entry then
6427 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6429 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6432 -- If the operation is marked "not overriding" and it's not primitive
6433 -- then an error is issued, unless this is an operation of a task or
6434 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6435 -- has been specified have already been checked above.
6437 elsif Must_Not_Override (Spec)
6438 and then not Is_Primitive
6439 and then Ekind (Subp) /= E_Entry
6440 and then Ekind (Scope (Subp)) /= E_Protected_Type
6443 ("overriding indicator only allowed if subprogram is primitive",
6447 end Check_Overriding_Indicator;
6453 -- Note: this procedure needs to know far too much about how the expander
6454 -- messes with exceptions. The use of the flag Exception_Junk and the
6455 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6456 -- works, but is not very clean. It would be better if the expansion
6457 -- routines would leave Original_Node working nicely, and we could use
6458 -- Original_Node here to ignore all the peculiar expander messing ???
6460 procedure Check_Returns
6464 Proc : Entity_Id := Empty)
6468 procedure Check_Statement_Sequence (L : List_Id);
6469 -- Internal recursive procedure to check a list of statements for proper
6470 -- termination by a return statement (or a transfer of control or a
6471 -- compound statement that is itself internally properly terminated).
6473 ------------------------------
6474 -- Check_Statement_Sequence --
6475 ------------------------------
6477 procedure Check_Statement_Sequence (L : List_Id) is
6482 function Assert_False return Boolean;
6483 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6484 -- rewritten as a null statement when assertions are off. The assert
6485 -- is not active, but it is still enough to kill the warning.
6491 function Assert_False return Boolean is
6492 Orig : constant Node_Id := Original_Node (Last_Stm);
6495 if Nkind (Orig) = N_Pragma
6496 and then Pragma_Name (Orig) = Name_Assert
6497 and then not Error_Posted (Orig)
6500 Arg : constant Node_Id :=
6501 First (Pragma_Argument_Associations (Orig));
6502 Exp : constant Node_Id := Expression (Arg);
6504 return Nkind (Exp) = N_Identifier
6505 and then Chars (Exp) = Name_False;
6515 Raise_Exception_Call : Boolean;
6516 -- Set True if statement sequence terminated by Raise_Exception call
6517 -- or a Reraise_Occurrence call.
6519 -- Start of processing for Check_Statement_Sequence
6522 Raise_Exception_Call := False;
6524 -- Get last real statement
6526 Last_Stm := Last (L);
6528 -- Deal with digging out exception handler statement sequences that
6529 -- have been transformed by the local raise to goto optimization.
6530 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6531 -- optimization has occurred, we are looking at something like:
6534 -- original stmts in block
6538 -- goto L1; | omitted if No_Exception_Propagation
6543 -- goto L3; -- skip handler when exception not raised
6545 -- <<L1>> -- target label for local exception
6559 -- and what we have to do is to dig out the estmts1 and estmts2
6560 -- sequences (which were the original sequences of statements in
6561 -- the exception handlers) and check them.
6563 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6568 exit when Nkind (Stm) /= N_Block_Statement;
6569 exit when not Exception_Junk (Stm);
6572 exit when Nkind (Stm) /= N_Label;
6573 exit when not Exception_Junk (Stm);
6574 Check_Statement_Sequence
6575 (Statements (Handled_Statement_Sequence (Next (Stm))));
6580 exit when Nkind (Stm) /= N_Goto_Statement;
6581 exit when not Exception_Junk (Stm);
6585 -- Don't count pragmas
6587 while Nkind (Last_Stm) = N_Pragma
6589 -- Don't count call to SS_Release (can happen after Raise_Exception)
6592 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6594 Nkind (Name (Last_Stm)) = N_Identifier
6596 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6598 -- Don't count exception junk
6601 (Nkind_In (Last_Stm, N_Goto_Statement,
6603 N_Object_Declaration)
6604 and then Exception_Junk (Last_Stm))
6605 or else Nkind (Last_Stm) in N_Push_xxx_Label
6606 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6608 -- Inserted code, such as finalization calls, is irrelevant: we only
6609 -- need to check original source.
6611 or else Is_Rewrite_Insertion (Last_Stm)
6616 -- Here we have the "real" last statement
6618 Kind := Nkind (Last_Stm);
6620 -- Transfer of control, OK. Note that in the No_Return procedure
6621 -- case, we already diagnosed any explicit return statements, so
6622 -- we can treat them as OK in this context.
6624 if Is_Transfer (Last_Stm) then
6627 -- Check cases of explicit non-indirect procedure calls
6629 elsif Kind = N_Procedure_Call_Statement
6630 and then Is_Entity_Name (Name (Last_Stm))
6632 -- Check call to Raise_Exception procedure which is treated
6633 -- specially, as is a call to Reraise_Occurrence.
6635 -- We suppress the warning in these cases since it is likely that
6636 -- the programmer really does not expect to deal with the case
6637 -- of Null_Occurrence, and thus would find a warning about a
6638 -- missing return curious, and raising Program_Error does not
6639 -- seem such a bad behavior if this does occur.
6641 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6642 -- behavior will be to raise Constraint_Error (see AI-329).
6644 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6646 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6648 Raise_Exception_Call := True;
6650 -- For Raise_Exception call, test first argument, if it is
6651 -- an attribute reference for a 'Identity call, then we know
6652 -- that the call cannot possibly return.
6655 Arg : constant Node_Id :=
6656 Original_Node (First_Actual (Last_Stm));
6658 if Nkind (Arg) = N_Attribute_Reference
6659 and then Attribute_Name (Arg) = Name_Identity
6666 -- If statement, need to look inside if there is an else and check
6667 -- each constituent statement sequence for proper termination.
6669 elsif Kind = N_If_Statement
6670 and then Present (Else_Statements (Last_Stm))
6672 Check_Statement_Sequence (Then_Statements (Last_Stm));
6673 Check_Statement_Sequence (Else_Statements (Last_Stm));
6675 if Present (Elsif_Parts (Last_Stm)) then
6677 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6680 while Present (Elsif_Part) loop
6681 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6689 -- Case statement, check each case for proper termination
6691 elsif Kind = N_Case_Statement then
6695 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6696 while Present (Case_Alt) loop
6697 Check_Statement_Sequence (Statements (Case_Alt));
6698 Next_Non_Pragma (Case_Alt);
6704 -- Block statement, check its handled sequence of statements
6706 elsif Kind = N_Block_Statement then
6712 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6721 -- Loop statement. If there is an iteration scheme, we can definitely
6722 -- fall out of the loop. Similarly if there is an exit statement, we
6723 -- can fall out. In either case we need a following return.
6725 elsif Kind = N_Loop_Statement then
6726 if Present (Iteration_Scheme (Last_Stm))
6727 or else Has_Exit (Entity (Identifier (Last_Stm)))
6731 -- A loop with no exit statement or iteration scheme is either
6732 -- an infinite loop, or it has some other exit (raise/return).
6733 -- In either case, no warning is required.
6739 -- Timed entry call, check entry call and delay alternatives
6741 -- Note: in expanded code, the timed entry call has been converted
6742 -- to a set of expanded statements on which the check will work
6743 -- correctly in any case.
6745 elsif Kind = N_Timed_Entry_Call then
6747 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6748 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6751 -- If statement sequence of entry call alternative is missing,
6752 -- then we can definitely fall through, and we post the error
6753 -- message on the entry call alternative itself.
6755 if No (Statements (ECA)) then
6758 -- If statement sequence of delay alternative is missing, then
6759 -- we can definitely fall through, and we post the error
6760 -- message on the delay alternative itself.
6762 -- Note: if both ECA and DCA are missing the return, then we
6763 -- post only one message, should be enough to fix the bugs.
6764 -- If not we will get a message next time on the DCA when the
6767 elsif No (Statements (DCA)) then
6770 -- Else check both statement sequences
6773 Check_Statement_Sequence (Statements (ECA));
6774 Check_Statement_Sequence (Statements (DCA));
6779 -- Conditional entry call, check entry call and else part
6781 -- Note: in expanded code, the conditional entry call has been
6782 -- converted to a set of expanded statements on which the check
6783 -- will work correctly in any case.
6785 elsif Kind = N_Conditional_Entry_Call then
6787 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6790 -- If statement sequence of entry call alternative is missing,
6791 -- then we can definitely fall through, and we post the error
6792 -- message on the entry call alternative itself.
6794 if No (Statements (ECA)) then
6797 -- Else check statement sequence and else part
6800 Check_Statement_Sequence (Statements (ECA));
6801 Check_Statement_Sequence (Else_Statements (Last_Stm));
6807 -- If we fall through, issue appropriate message
6811 -- Kill warning if last statement is a raise exception call,
6812 -- or a pragma Assert (False). Note that with assertions enabled,
6813 -- such a pragma has been converted into a raise exception call
6814 -- already, so the Assert_False is for the assertions off case.
6816 if not Raise_Exception_Call and then not Assert_False then
6818 -- In GNATprove mode, it is an error to have a missing return
6820 Error_Msg_Warn := SPARK_Mode /= On;
6822 -- Issue error message or warning
6825 ("RETURN statement missing following this statement<<!",
6828 ("\Program_Error ]<<!", Last_Stm);
6831 -- Note: we set Err even though we have not issued a warning
6832 -- because we still have a case of a missing return. This is
6833 -- an extremely marginal case, probably will never be noticed
6834 -- but we might as well get it right.
6838 -- Otherwise we have the case of a procedure marked No_Return
6841 if not Raise_Exception_Call then
6842 if GNATprove_Mode then
6844 ("implied return after this statement would have raised "
6845 & "Program_Error", Last_Stm);
6847 -- In normal compilation mode, do not warn on a generated call
6848 -- (e.g. in the body of a renaming as completion).
6850 elsif Comes_From_Source (Last_Stm) then
6852 ("implied return after this statement will raise "
6853 & "Program_Error??", Last_Stm);
6856 Error_Msg_Warn := SPARK_Mode /= On;
6858 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6862 RE : constant Node_Id :=
6863 Make_Raise_Program_Error (Sloc (Last_Stm),
6864 Reason => PE_Implicit_Return);
6866 Insert_After (Last_Stm, RE);
6870 end Check_Statement_Sequence;
6872 -- Start of processing for Check_Returns
6876 Check_Statement_Sequence (Statements (HSS));
6878 if Present (Exception_Handlers (HSS)) then
6879 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6880 while Present (Handler) loop
6881 Check_Statement_Sequence (Statements (Handler));
6882 Next_Non_Pragma (Handler);
6887 ----------------------------
6888 -- Check_Subprogram_Order --
6889 ----------------------------
6891 procedure Check_Subprogram_Order (N : Node_Id) is
6893 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6894 -- This is used to check if S1 > S2 in the sense required by this test,
6895 -- for example nameab < namec, but name2 < name10.
6897 -----------------------------
6898 -- Subprogram_Name_Greater --
6899 -----------------------------
6901 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6906 -- Deal with special case where names are identical except for a
6907 -- numerical suffix. These are handled specially, taking the numeric
6908 -- ordering from the suffix into account.
6911 while S1 (L1) in '0' .. '9' loop
6916 while S2 (L2) in '0' .. '9' loop
6920 -- If non-numeric parts non-equal, do straight compare
6922 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6925 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6926 -- that a missing suffix is treated as numeric zero in this test.
6930 while L1 < S1'Last loop
6932 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6936 while L2 < S2'Last loop
6938 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6943 end Subprogram_Name_Greater;
6945 -- Start of processing for Check_Subprogram_Order
6948 -- Check body in alpha order if this is option
6951 and then Style_Check_Order_Subprograms
6952 and then Nkind (N) = N_Subprogram_Body
6953 and then Comes_From_Source (N)
6954 and then In_Extended_Main_Source_Unit (N)
6958 renames Scope_Stack.Table
6959 (Scope_Stack.Last).Last_Subprogram_Name;
6961 Body_Id : constant Entity_Id :=
6962 Defining_Entity (Specification (N));
6965 Get_Decoded_Name_String (Chars (Body_Id));
6968 if Subprogram_Name_Greater
6969 (LSN.all, Name_Buffer (1 .. Name_Len))
6971 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6977 LSN := new String'(Name_Buffer (1 .. Name_Len));
6980 end Check_Subprogram_Order;
6982 ------------------------------
6983 -- Check_Subtype_Conformant --
6984 ------------------------------
6986 procedure Check_Subtype_Conformant
6987 (New_Id : Entity_Id;
6989 Err_Loc : Node_Id := Empty;
6990 Skip_Controlling_Formals : Boolean := False;
6991 Get_Inst : Boolean := False)
6994 pragma Warnings (Off, Result);
6997 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
6998 Skip_Controlling_Formals => Skip_Controlling_Formals,
6999 Get_Inst => Get_Inst);
7000 end Check_Subtype_Conformant;
7002 -----------------------------------
7003 -- Check_Synchronized_Overriding --
7004 -----------------------------------
7006 procedure Check_Synchronized_Overriding
7007 (Def_Id : Entity_Id;
7008 Overridden_Subp : out Entity_Id)
7010 Ifaces_List : Elist_Id;
7014 function Matches_Prefixed_View_Profile
7015 (Prim_Params : List_Id;
7016 Iface_Params : List_Id) return Boolean;
7017 -- Determine whether a subprogram's parameter profile Prim_Params
7018 -- matches that of a potentially overridden interface subprogram
7019 -- Iface_Params. Also determine if the type of first parameter of
7020 -- Iface_Params is an implemented interface.
7022 -----------------------------------
7023 -- Matches_Prefixed_View_Profile --
7024 -----------------------------------
7026 function Matches_Prefixed_View_Profile
7027 (Prim_Params : List_Id;
7028 Iface_Params : List_Id) return Boolean
7030 function Is_Implemented
7031 (Ifaces_List : Elist_Id;
7032 Iface : Entity_Id) return Boolean;
7033 -- Determine if Iface is implemented by the current task or
7036 --------------------
7037 -- Is_Implemented --
7038 --------------------
7040 function Is_Implemented
7041 (Ifaces_List : Elist_Id;
7042 Iface : Entity_Id) return Boolean
7044 Iface_Elmt : Elmt_Id;
7047 Iface_Elmt := First_Elmt (Ifaces_List);
7048 while Present (Iface_Elmt) loop
7049 if Node (Iface_Elmt) = Iface then
7053 Next_Elmt (Iface_Elmt);
7061 Iface_Id : Entity_Id;
7062 Iface_Param : Node_Id;
7063 Iface_Typ : Entity_Id;
7064 Prim_Id : Entity_Id;
7065 Prim_Param : Node_Id;
7066 Prim_Typ : Entity_Id;
7068 -- Start of processing for Matches_Prefixed_View_Profile
7071 Iface_Param := First (Iface_Params);
7072 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7074 if Is_Access_Type (Iface_Typ) then
7075 Iface_Typ := Designated_Type (Iface_Typ);
7078 Prim_Param := First (Prim_Params);
7080 -- The first parameter of the potentially overridden subprogram must
7081 -- be an interface implemented by Prim.
7083 if not Is_Interface (Iface_Typ)
7084 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7089 -- The checks on the object parameters are done, so move on to the
7090 -- rest of the parameters.
7092 if not In_Scope then
7093 Prim_Param := Next (Prim_Param);
7096 Iface_Param := Next (Iface_Param);
7097 while Present (Iface_Param) and then Present (Prim_Param) loop
7098 Iface_Id := Defining_Identifier (Iface_Param);
7099 Iface_Typ := Find_Parameter_Type (Iface_Param);
7101 Prim_Id := Defining_Identifier (Prim_Param);
7102 Prim_Typ := Find_Parameter_Type (Prim_Param);
7104 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7105 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7106 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7108 Iface_Typ := Designated_Type (Iface_Typ);
7109 Prim_Typ := Designated_Type (Prim_Typ);
7112 -- Case of multiple interface types inside a parameter profile
7114 -- (Obj_Param : in out Iface; ...; Param : Iface)
7116 -- If the interface type is implemented, then the matching type in
7117 -- the primitive should be the implementing record type.
7119 if Ekind (Iface_Typ) = E_Record_Type
7120 and then Is_Interface (Iface_Typ)
7121 and then Is_Implemented (Ifaces_List, Iface_Typ)
7123 if Prim_Typ /= Typ then
7127 -- The two parameters must be both mode and subtype conformant
7129 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7131 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7140 -- One of the two lists contains more parameters than the other
7142 if Present (Iface_Param) or else Present (Prim_Param) then
7147 end Matches_Prefixed_View_Profile;
7149 -- Start of processing for Check_Synchronized_Overriding
7152 Overridden_Subp := Empty;
7154 -- Def_Id must be an entry or a subprogram. We should skip predefined
7155 -- primitives internally generated by the front end; however at this
7156 -- stage predefined primitives are still not fully decorated. As a
7157 -- minor optimization we skip here internally generated subprograms.
7159 if (Ekind (Def_Id) /= E_Entry
7160 and then Ekind (Def_Id) /= E_Function
7161 and then Ekind (Def_Id) /= E_Procedure)
7162 or else not Comes_From_Source (Def_Id)
7167 -- Search for the concurrent declaration since it contains the list of
7168 -- all implemented interfaces. In this case, the subprogram is declared
7169 -- within the scope of a protected or a task type.
7171 if Present (Scope (Def_Id))
7172 and then Is_Concurrent_Type (Scope (Def_Id))
7173 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7175 Typ := Scope (Def_Id);
7178 -- The enclosing scope is not a synchronized type and the subprogram
7181 elsif No (First_Formal (Def_Id)) then
7184 -- The subprogram has formals and hence it may be a primitive of a
7188 Typ := Etype (First_Formal (Def_Id));
7190 if Is_Access_Type (Typ) then
7191 Typ := Directly_Designated_Type (Typ);
7194 if Is_Concurrent_Type (Typ)
7195 and then not Is_Generic_Actual_Type (Typ)
7199 -- This case occurs when the concurrent type is declared within a
7200 -- generic unit. As a result the corresponding record has been built
7201 -- and used as the type of the first formal, we just have to retrieve
7202 -- the corresponding concurrent type.
7204 elsif Is_Concurrent_Record_Type (Typ)
7205 and then not Is_Class_Wide_Type (Typ)
7206 and then Present (Corresponding_Concurrent_Type (Typ))
7208 Typ := Corresponding_Concurrent_Type (Typ);
7216 -- There is no overriding to check if this is an inherited operation in
7217 -- a type derivation for a generic actual.
7219 Collect_Interfaces (Typ, Ifaces_List);
7221 if Is_Empty_Elmt_List (Ifaces_List) then
7225 -- Determine whether entry or subprogram Def_Id overrides a primitive
7226 -- operation that belongs to one of the interfaces in Ifaces_List.
7229 Candidate : Entity_Id := Empty;
7230 Hom : Entity_Id := Empty;
7231 Subp : Entity_Id := Empty;
7234 -- Traverse the homonym chain, looking for a potentially overridden
7235 -- subprogram that belongs to an implemented interface.
7237 Hom := Current_Entity_In_Scope (Def_Id);
7238 while Present (Hom) loop
7242 or else not Is_Overloadable (Subp)
7243 or else not Is_Primitive (Subp)
7244 or else not Is_Dispatching_Operation (Subp)
7245 or else not Present (Find_Dispatching_Type (Subp))
7246 or else not Is_Interface (Find_Dispatching_Type (Subp))
7250 -- Entries and procedures can override abstract or null interface
7253 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7254 and then Ekind (Subp) = E_Procedure
7255 and then Matches_Prefixed_View_Profile
7256 (Parameter_Specifications (Parent (Def_Id)),
7257 Parameter_Specifications (Parent (Subp)))
7261 -- For an overridden subprogram Subp, check whether the mode
7262 -- of its first parameter is correct depending on the kind of
7263 -- synchronized type.
7266 Formal : constant Node_Id := First_Formal (Candidate);
7269 -- In order for an entry or a protected procedure to
7270 -- override, the first parameter of the overridden routine
7271 -- must be of mode "out", "in out", or access-to-variable.
7273 if Ekind_In (Candidate, E_Entry, E_Procedure)
7274 and then Is_Protected_Type (Typ)
7275 and then Ekind (Formal) /= E_In_Out_Parameter
7276 and then Ekind (Formal) /= E_Out_Parameter
7277 and then Nkind (Parameter_Type (Parent (Formal))) /=
7282 -- All other cases are OK since a task entry or routine does
7283 -- not have a restriction on the mode of the first parameter
7284 -- of the overridden interface routine.
7287 Overridden_Subp := Candidate;
7292 -- Functions can override abstract interface functions
7294 elsif Ekind (Def_Id) = E_Function
7295 and then Ekind (Subp) = E_Function
7296 and then Matches_Prefixed_View_Profile
7297 (Parameter_Specifications (Parent (Def_Id)),
7298 Parameter_Specifications (Parent (Subp)))
7299 and then Etype (Def_Id) = Etype (Subp)
7303 -- If an inherited subprogram is implemented by a protected
7304 -- function, then the first parameter of the inherited
7305 -- subprogram shall be of mode in, but not an access-to-
7306 -- variable parameter (RM 9.4(11/9)).
7308 if Present (First_Formal (Subp))
7309 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7311 (not Is_Access_Type (Etype (First_Formal (Subp)))
7313 Is_Access_Constant (Etype (First_Formal (Subp))))
7315 Overridden_Subp := Subp;
7320 Hom := Homonym (Hom);
7323 -- After examining all candidates for overriding, we are left with
7324 -- the best match, which is a mode-incompatible interface routine.
7326 if In_Scope and then Present (Candidate) then
7327 Error_Msg_PT (Def_Id, Candidate);
7330 Overridden_Subp := Candidate;
7333 end Check_Synchronized_Overriding;
7335 ---------------------------
7336 -- Check_Type_Conformant --
7337 ---------------------------
7339 procedure Check_Type_Conformant
7340 (New_Id : Entity_Id;
7342 Err_Loc : Node_Id := Empty)
7345 pragma Warnings (Off, Result);
7348 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7349 end Check_Type_Conformant;
7351 ---------------------------
7352 -- Can_Override_Operator --
7353 ---------------------------
7355 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7359 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7363 Typ := Base_Type (Etype (First_Formal (Subp)));
7365 -- Check explicitly that the operation is a primitive of the type
7367 return Operator_Matches_Spec (Subp, Subp)
7368 and then not Is_Generic_Type (Typ)
7369 and then Scope (Subp) = Scope (Typ)
7370 and then not Is_Class_Wide_Type (Typ);
7372 end Can_Override_Operator;
7374 ----------------------
7375 -- Conforming_Types --
7376 ----------------------
7378 function Conforming_Types
7381 Ctype : Conformance_Type;
7382 Get_Inst : Boolean := False) return Boolean
7384 function Base_Types_Match
7386 Typ_2 : Entity_Id) return Boolean;
7387 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7388 -- in different scopes (e.g. parent and child instances), then verify
7389 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7390 -- the same subtype chain. The whole purpose of this procedure is to
7391 -- prevent spurious ambiguities in an instantiation that may arise if
7392 -- two distinct generic types are instantiated with the same actual.
7394 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7395 -- An access parameter can designate an incomplete type. If the
7396 -- incomplete type is the limited view of a type from a limited_
7397 -- with_clause, check whether the non-limited view is available.
7398 -- If it is a (non-limited) incomplete type, get the full view.
7400 function Matches_Limited_With_View
7402 Typ_2 : Entity_Id) return Boolean;
7403 -- Returns True if and only if either Typ_1 denotes a limited view of
7404 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7405 -- the limited with view of a type is used in a subprogram declaration
7406 -- and the subprogram body is in the scope of a regular with clause for
7407 -- the same unit. In such a case, the two type entities are considered
7408 -- identical for purposes of conformance checking.
7410 ----------------------
7411 -- Base_Types_Match --
7412 ----------------------
7414 function Base_Types_Match
7416 Typ_2 : Entity_Id) return Boolean
7418 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7419 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7422 if Typ_1 = Typ_2 then
7425 elsif Base_1 = Base_2 then
7427 -- The following is too permissive. A more precise test should
7428 -- check that the generic actual is an ancestor subtype of the
7431 -- See code in Find_Corresponding_Spec that applies an additional
7432 -- filter to handle accidental amiguities in instances.
7435 not Is_Generic_Actual_Type (Typ_1)
7436 or else not Is_Generic_Actual_Type (Typ_2)
7437 or else Scope (Typ_1) /= Scope (Typ_2);
7439 -- If Typ_2 is a generic actual type it is declared as the subtype of
7440 -- the actual. If that actual is itself a subtype we need to use its
7441 -- own base type to check for compatibility.
7443 elsif Ekind (Base_2) = Ekind (Typ_2)
7444 and then Base_1 = Base_Type (Base_2)
7448 elsif Ekind (Base_1) = Ekind (Typ_1)
7449 and then Base_2 = Base_Type (Base_1)
7456 end Base_Types_Match;
7458 --------------------------
7459 -- Find_Designated_Type --
7460 --------------------------
7462 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7466 Desig := Directly_Designated_Type (Typ);
7468 if Ekind (Desig) = E_Incomplete_Type then
7470 -- If regular incomplete type, get full view if available
7472 if Present (Full_View (Desig)) then
7473 Desig := Full_View (Desig);
7475 -- If limited view of a type, get non-limited view if available,
7476 -- and check again for a regular incomplete type.
7478 elsif Present (Non_Limited_View (Desig)) then
7479 Desig := Get_Full_View (Non_Limited_View (Desig));
7484 end Find_Designated_Type;
7486 -------------------------------
7487 -- Matches_Limited_With_View --
7488 -------------------------------
7490 function Matches_Limited_With_View
7492 Typ_2 : Entity_Id) return Boolean
7494 function Is_Matching_Limited_View
7496 View : Entity_Id) return Boolean;
7497 -- Determine whether non-limited view View denotes type Typ in some
7498 -- conformant fashion.
7500 ------------------------------
7501 -- Is_Matching_Limited_View --
7502 ------------------------------
7504 function Is_Matching_Limited_View
7506 View : Entity_Id) return Boolean
7508 Root_Typ : Entity_Id;
7509 Root_View : Entity_Id;
7512 -- The non-limited view directly denotes the type
7517 -- The type is a subtype of the non-limited view
7519 elsif Is_Subtype_Of (Typ, View) then
7522 -- Both the non-limited view and the type denote class-wide types
7524 elsif Is_Class_Wide_Type (Typ)
7525 and then Is_Class_Wide_Type (View)
7527 Root_Typ := Root_Type (Typ);
7528 Root_View := Root_Type (View);
7530 if Root_Typ = Root_View then
7533 -- An incomplete tagged type and its full view may receive two
7534 -- distinct class-wide types when the related package has not
7535 -- been analyzed yet.
7538 -- type T is tagged; -- CW_1
7539 -- type T is tagged null record; -- CW_2
7542 -- This is because the package lacks any semantic information
7543 -- that may eventually link both views of T. As a consequence,
7544 -- a client of the limited view of Pack will see CW_2 while a
7545 -- client of the non-limited view of Pack will see CW_1.
7547 elsif Is_Incomplete_Type (Root_Typ)
7548 and then Present (Full_View (Root_Typ))
7549 and then Full_View (Root_Typ) = Root_View
7553 elsif Is_Incomplete_Type (Root_View)
7554 and then Present (Full_View (Root_View))
7555 and then Full_View (Root_View) = Root_Typ
7562 end Is_Matching_Limited_View;
7564 -- Start of processing for Matches_Limited_With_View
7567 -- In some cases a type imported through a limited_with clause, and
7568 -- its non-limited view are both visible, for example in an anonymous
7569 -- access-to-class-wide type in a formal, or when building the body
7570 -- for a subprogram renaming after the subprogram has been frozen.
7571 -- In these cases both entities designate the same type. In addition,
7572 -- if one of them is an actual in an instance, it may be a subtype of
7573 -- the non-limited view of the other.
7575 if From_Limited_With (Typ_1)
7576 and then From_Limited_With (Typ_2)
7577 and then Available_View (Typ_1) = Available_View (Typ_2)
7581 elsif From_Limited_With (Typ_1) then
7582 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7584 elsif From_Limited_With (Typ_2) then
7585 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7590 end Matches_Limited_With_View;
7594 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7596 Type_1 : Entity_Id := T1;
7597 Type_2 : Entity_Id := T2;
7599 -- Start of processing for Conforming_Types
7602 -- The context is an instance association for a formal access-to-
7603 -- subprogram type; the formal parameter types require mapping because
7604 -- they may denote other formal parameters of the generic unit.
7607 Type_1 := Get_Instance_Of (T1);
7608 Type_2 := Get_Instance_Of (T2);
7611 -- If one of the types is a view of the other introduced by a limited
7612 -- with clause, treat these as conforming for all purposes.
7614 if Matches_Limited_With_View (T1, T2) then
7617 elsif Base_Types_Match (Type_1, Type_2) then
7618 if Ctype <= Mode_Conformant then
7623 Subtypes_Statically_Match (Type_1, Type_2)
7624 and then Dimensions_Match (Type_1, Type_2);
7627 elsif Is_Incomplete_Or_Private_Type (Type_1)
7628 and then Present (Full_View (Type_1))
7629 and then Base_Types_Match (Full_View (Type_1), Type_2)
7632 Ctype <= Mode_Conformant
7633 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7635 elsif Ekind (Type_2) = E_Incomplete_Type
7636 and then Present (Full_View (Type_2))
7637 and then Base_Types_Match (Type_1, Full_View (Type_2))
7640 Ctype <= Mode_Conformant
7641 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7643 elsif Is_Private_Type (Type_2)
7644 and then In_Instance
7645 and then Present (Full_View (Type_2))
7646 and then Base_Types_Match (Type_1, Full_View (Type_2))
7649 Ctype <= Mode_Conformant
7650 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7652 -- Another confusion between views in a nested instance with an
7653 -- actual private type whose full view is not in scope.
7655 elsif Ekind (Type_2) = E_Private_Subtype
7656 and then In_Instance
7657 and then Etype (Type_2) = Type_1
7661 -- In Ada 2012, incomplete types (including limited views) can appear
7662 -- as actuals in instantiations.
7664 elsif Is_Incomplete_Type (Type_1)
7665 and then Is_Incomplete_Type (Type_2)
7666 and then (Used_As_Generic_Actual (Type_1)
7667 or else Used_As_Generic_Actual (Type_2))
7672 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7673 -- treated recursively because they carry a signature. As far as
7674 -- conformance is concerned, convention plays no role, and either
7675 -- or both could be access to protected subprograms.
7677 Are_Anonymous_Access_To_Subprogram_Types :=
7678 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7679 E_Anonymous_Access_Protected_Subprogram_Type)
7681 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7682 E_Anonymous_Access_Protected_Subprogram_Type);
7684 -- Test anonymous access type case. For this case, static subtype
7685 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7686 -- the base types because we may have built internal subtype entities
7687 -- to handle null-excluding types (see Process_Formals).
7689 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7691 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7693 -- Ada 2005 (AI-254)
7695 or else Are_Anonymous_Access_To_Subprogram_Types
7698 Desig_1 : Entity_Id;
7699 Desig_2 : Entity_Id;
7702 -- In Ada 2005, access constant indicators must match for
7703 -- subtype conformance.
7705 if Ada_Version >= Ada_2005
7706 and then Ctype >= Subtype_Conformant
7708 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7713 Desig_1 := Find_Designated_Type (Type_1);
7714 Desig_2 := Find_Designated_Type (Type_2);
7716 -- If the context is an instance association for a formal
7717 -- access-to-subprogram type; formal access parameter designated
7718 -- types require mapping because they may denote other formal
7719 -- parameters of the generic unit.
7722 Desig_1 := Get_Instance_Of (Desig_1);
7723 Desig_2 := Get_Instance_Of (Desig_2);
7726 -- It is possible for a Class_Wide_Type to be introduced for an
7727 -- incomplete type, in which case there is a separate class_ wide
7728 -- type for the full view. The types conform if their Etypes
7729 -- conform, i.e. one may be the full view of the other. This can
7730 -- only happen in the context of an access parameter, other uses
7731 -- of an incomplete Class_Wide_Type are illegal.
7733 if Is_Class_Wide_Type (Desig_1)
7735 Is_Class_Wide_Type (Desig_2)
7739 (Etype (Base_Type (Desig_1)),
7740 Etype (Base_Type (Desig_2)), Ctype);
7742 elsif Are_Anonymous_Access_To_Subprogram_Types then
7743 if Ada_Version < Ada_2005 then
7745 Ctype = Type_Conformant
7746 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7748 -- We must check the conformance of the signatures themselves
7752 Conformant : Boolean;
7755 (Desig_1, Desig_2, Ctype, False, Conformant);
7760 -- A limited view of an actual matches the corresponding
7761 -- incomplete formal.
7763 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7764 and then From_Limited_With (Desig_2)
7765 and then Used_As_Generic_Actual (Etype (Desig_2))
7770 return Base_Type (Desig_1) = Base_Type (Desig_2)
7771 and then (Ctype = Type_Conformant
7773 Subtypes_Statically_Match (Desig_1, Desig_2));
7777 -- Otherwise definitely no match
7780 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7781 and then Is_Access_Type (Type_2))
7782 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7783 and then Is_Access_Type (Type_1)))
7786 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7788 May_Hide_Profile := True;
7793 end Conforming_Types;
7795 --------------------------
7796 -- Create_Extra_Formals --
7797 --------------------------
7799 procedure Create_Extra_Formals (E : Entity_Id) is
7800 First_Extra : Entity_Id := Empty;
7802 Last_Extra : Entity_Id := Empty;
7804 function Add_Extra_Formal
7805 (Assoc_Entity : Entity_Id;
7808 Suffix : String) return Entity_Id;
7809 -- Add an extra formal to the current list of formals and extra formals.
7810 -- The extra formal is added to the end of the list of extra formals,
7811 -- and also returned as the result. These formals are always of mode IN.
7812 -- The new formal has the type Typ, is declared in Scope, and its name
7813 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7814 -- The following suffixes are currently used. They should not be changed
7815 -- without coordinating with CodePeer, which makes use of these to
7816 -- provide better messages.
7818 -- O denotes the Constrained bit.
7819 -- L denotes the accessibility level.
7820 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7821 -- the full list in exp_ch6.BIP_Formal_Kind.
7823 ----------------------
7824 -- Add_Extra_Formal --
7825 ----------------------
7827 function Add_Extra_Formal
7828 (Assoc_Entity : Entity_Id;
7831 Suffix : String) return Entity_Id
7833 EF : constant Entity_Id :=
7834 Make_Defining_Identifier (Sloc (Assoc_Entity),
7835 Chars => New_External_Name (Chars (Assoc_Entity),
7839 -- A little optimization. Never generate an extra formal for the
7840 -- _init operand of an initialization procedure, since it could
7843 if Chars (Formal) = Name_uInit then
7847 Set_Ekind (EF, E_In_Parameter);
7848 Set_Actual_Subtype (EF, Typ);
7849 Set_Etype (EF, Typ);
7850 Set_Scope (EF, Scope);
7851 Set_Mechanism (EF, Default_Mechanism);
7852 Set_Formal_Validity (EF);
7854 if No (First_Extra) then
7856 Set_Extra_Formals (Scope, EF);
7859 if Present (Last_Extra) then
7860 Set_Extra_Formal (Last_Extra, EF);
7866 end Add_Extra_Formal;
7870 Formal_Type : Entity_Id;
7871 P_Formal : Entity_Id := Empty;
7873 -- Start of processing for Create_Extra_Formals
7876 -- We never generate extra formals if expansion is not active because we
7877 -- don't need them unless we are generating code.
7879 if not Expander_Active then
7883 -- No need to generate extra formals in interface thunks whose target
7884 -- primitive has no extra formals.
7886 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7890 -- If this is a derived subprogram then the subtypes of the parent
7891 -- subprogram's formal parameters will be used to determine the need
7892 -- for extra formals.
7894 if Is_Overloadable (E) and then Present (Alias (E)) then
7895 P_Formal := First_Formal (Alias (E));
7898 Formal := First_Formal (E);
7899 while Present (Formal) loop
7900 Last_Extra := Formal;
7901 Next_Formal (Formal);
7904 -- If Extra_Formals were already created, don't do it again. This
7905 -- situation may arise for subprogram types created as part of
7906 -- dispatching calls (see Expand_Dispatching_Call).
7908 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7912 -- If the subprogram is a predefined dispatching subprogram then don't
7913 -- generate any extra constrained or accessibility level formals. In
7914 -- general we suppress these for internal subprograms (by not calling
7915 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7916 -- generated stream attributes do get passed through because extra
7917 -- build-in-place formals are needed in some cases (limited 'Input).
7919 if Is_Predefined_Internal_Operation (E) then
7920 goto Test_For_Func_Result_Extras;
7923 Formal := First_Formal (E);
7924 while Present (Formal) loop
7926 -- Create extra formal for supporting the attribute 'Constrained.
7927 -- The case of a private type view without discriminants also
7928 -- requires the extra formal if the underlying type has defaulted
7931 if Ekind (Formal) /= E_In_Parameter then
7932 if Present (P_Formal) then
7933 Formal_Type := Etype (P_Formal);
7935 Formal_Type := Etype (Formal);
7938 -- Do not produce extra formals for Unchecked_Union parameters.
7939 -- Jump directly to the end of the loop.
7941 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7942 goto Skip_Extra_Formal_Generation;
7945 if not Has_Discriminants (Formal_Type)
7946 and then Ekind (Formal_Type) in Private_Kind
7947 and then Present (Underlying_Type (Formal_Type))
7949 Formal_Type := Underlying_Type (Formal_Type);
7952 -- Suppress the extra formal if formal's subtype is constrained or
7953 -- indefinite, or we're compiling for Ada 2012 and the underlying
7954 -- type is tagged and limited. In Ada 2012, a limited tagged type
7955 -- can have defaulted discriminants, but 'Constrained is required
7956 -- to return True, so the formal is never needed (see AI05-0214).
7957 -- Note that this ensures consistency of calling sequences for
7958 -- dispatching operations when some types in a class have defaults
7959 -- on discriminants and others do not (and requiring the extra
7960 -- formal would introduce distributed overhead).
7962 -- If the type does not have a completion yet, treat as prior to
7963 -- Ada 2012 for consistency.
7965 if Has_Discriminants (Formal_Type)
7966 and then not Is_Constrained (Formal_Type)
7967 and then Is_Definite_Subtype (Formal_Type)
7968 and then (Ada_Version < Ada_2012
7969 or else No (Underlying_Type (Formal_Type))
7971 (Is_Limited_Type (Formal_Type)
7974 (Underlying_Type (Formal_Type)))))
7976 Set_Extra_Constrained
7977 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
7981 -- Create extra formal for supporting accessibility checking. This
7982 -- is done for both anonymous access formals and formals of named
7983 -- access types that are marked as controlling formals. The latter
7984 -- case can occur when Expand_Dispatching_Call creates a subprogram
7985 -- type and substitutes the types of access-to-class-wide actuals
7986 -- for the anonymous access-to-specific-type of controlling formals.
7987 -- Base_Type is applied because in cases where there is a null
7988 -- exclusion the formal may have an access subtype.
7990 -- This is suppressed if we specifically suppress accessibility
7991 -- checks at the package level for either the subprogram, or the
7992 -- package in which it resides. However, we do not suppress it
7993 -- simply if the scope has accessibility checks suppressed, since
7994 -- this could cause trouble when clients are compiled with a
7995 -- different suppression setting. The explicit checks at the
7996 -- package level are safe from this point of view.
7998 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
7999 or else (Is_Controlling_Formal (Formal)
8000 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8002 (Explicit_Suppress (E, Accessibility_Check)
8004 Explicit_Suppress (Scope (E), Accessibility_Check))
8007 or else Present (Extra_Accessibility (P_Formal)))
8009 Set_Extra_Accessibility
8010 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8013 -- This label is required when skipping extra formal generation for
8014 -- Unchecked_Union parameters.
8016 <<Skip_Extra_Formal_Generation>>
8018 if Present (P_Formal) then
8019 Next_Formal (P_Formal);
8022 Next_Formal (Formal);
8025 <<Test_For_Func_Result_Extras>>
8027 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8028 -- function call is ... determined by the point of call ...".
8030 if Needs_Result_Accessibility_Level (E) then
8031 Set_Extra_Accessibility_Of_Result
8032 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8035 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8036 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8038 if Is_Build_In_Place_Function (E) then
8040 Result_Subt : constant Entity_Id := Etype (E);
8041 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8042 Formal_Typ : Entity_Id;
8043 Subp_Decl : Node_Id;
8044 Discard : Entity_Id;
8047 -- In the case of functions with unconstrained result subtypes,
8048 -- add a 4-state formal indicating whether the return object is
8049 -- allocated by the caller (1), or should be allocated by the
8050 -- callee on the secondary stack (2), in the global heap (3), or
8051 -- in a user-defined storage pool (4). For the moment we just use
8052 -- Natural for the type of this formal. Note that this formal
8053 -- isn't usually needed in the case where the result subtype is
8054 -- constrained, but it is needed when the function has a tagged
8055 -- result, because generally such functions can be called in a
8056 -- dispatching context and such calls must be handled like calls
8057 -- to a class-wide function.
8059 if Needs_BIP_Alloc_Form (E) then
8062 (E, Standard_Natural,
8063 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8065 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8066 -- use a user-defined pool. This formal is not added on
8067 -- ZFP as those targets do not support pools.
8069 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8072 (E, RTE (RE_Root_Storage_Pool_Ptr),
8073 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8077 -- In the case of functions whose result type needs finalization,
8078 -- add an extra formal which represents the finalization master.
8080 if Needs_BIP_Finalization_Master (E) then
8083 (E, RTE (RE_Finalization_Master_Ptr),
8084 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8087 -- When the result type contains tasks, add two extra formals: the
8088 -- master of the tasks to be created, and the caller's activation
8091 if Has_Task (Full_Subt) then
8094 (E, RTE (RE_Master_Id),
8095 E, BIP_Formal_Suffix (BIP_Task_Master));
8098 (E, RTE (RE_Activation_Chain_Access),
8099 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8102 -- All build-in-place functions get an extra formal that will be
8103 -- passed the address of the return object within the caller.
8106 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8108 -- Incomplete_View_From_Limited_With is needed here because
8109 -- gigi gets confused if the designated type is the full view
8110 -- coming from a limited-with'ed package. In the normal case,
8111 -- (no limited with) Incomplete_View_From_Limited_With
8112 -- returns Result_Subt.
8114 Set_Directly_Designated_Type
8115 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8116 Set_Etype (Formal_Typ, Formal_Typ);
8117 Set_Depends_On_Private
8118 (Formal_Typ, Has_Private_Component (Formal_Typ));
8119 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8120 Set_Is_Access_Constant (Formal_Typ, False);
8122 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8123 -- the designated type comes from the limited view (for back-end
8126 Set_From_Limited_With
8127 (Formal_Typ, From_Limited_With (Result_Subt));
8129 Layout_Type (Formal_Typ);
8131 -- Force the definition of the Itype in case of internal function
8132 -- calls within the same or nested scope.
8134 if Is_Subprogram_Or_Generic_Subprogram (E) then
8135 Subp_Decl := Parent (E);
8137 -- The insertion point for an Itype reference should be after
8138 -- the unit declaration node of the subprogram. An exception
8139 -- to this are inherited operations from a parent type in which
8140 -- case the derived type acts as their parent.
8142 if Nkind_In (Subp_Decl, N_Function_Specification,
8143 N_Procedure_Specification)
8145 Subp_Decl := Parent (Subp_Decl);
8148 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8153 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8157 -- If this is an instance of a generic, we need to have extra formals
8160 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8161 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8163 end Create_Extra_Formals;
8165 -----------------------------
8166 -- Enter_Overloaded_Entity --
8167 -----------------------------
8169 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8170 function Matches_Predefined_Op return Boolean;
8171 -- This returns an approximation of whether S matches a predefined
8172 -- operator, based on the operator symbol, and the parameter and result
8173 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8175 ---------------------------
8176 -- Matches_Predefined_Op --
8177 ---------------------------
8179 function Matches_Predefined_Op return Boolean is
8180 Formal_1 : constant Entity_Id := First_Formal (S);
8181 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8182 Op : constant Name_Id := Chars (S);
8183 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8184 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8189 if Present (Formal_2) then
8191 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8194 -- All but "&" and "**" have same-types parameters
8203 if Type_1 /= Type_2 then
8208 -- Check parameter and result types
8216 Is_Boolean_Type (Result_Type)
8217 and then Result_Type = Type_1;
8223 Is_Integer_Type (Result_Type)
8224 and then Result_Type = Type_1;
8232 Is_Numeric_Type (Result_Type)
8233 and then Result_Type = Type_1;
8239 Is_Boolean_Type (Result_Type)
8240 and then not Is_Limited_Type (Type_1);
8248 Is_Boolean_Type (Result_Type)
8249 and then (Is_Array_Type (Type_1)
8250 or else Is_Scalar_Type (Type_1));
8252 when Name_Op_Concat =>
8253 return Is_Array_Type (Result_Type);
8255 when Name_Op_Expon =>
8257 (Is_Integer_Type (Result_Type)
8258 or else Is_Floating_Point_Type (Result_Type))
8259 and then Result_Type = Type_1
8260 and then Type_2 = Standard_Integer;
8263 raise Program_Error;
8276 Is_Numeric_Type (Result_Type)
8277 and then Result_Type = Type_1;
8281 Is_Boolean_Type (Result_Type)
8282 and then Result_Type = Type_1;
8285 raise Program_Error;
8288 end Matches_Predefined_Op;
8292 E : Entity_Id := Current_Entity_In_Scope (S);
8293 C_E : Entity_Id := Current_Entity (S);
8295 -- Start of processing for Enter_Overloaded_Entity
8299 Set_Has_Homonym (E);
8300 Set_Has_Homonym (S);
8303 Set_Is_Immediately_Visible (S);
8304 Set_Scope (S, Current_Scope);
8306 -- Chain new entity if front of homonym in current scope, so that
8307 -- homonyms are contiguous.
8309 if Present (E) and then E /= C_E then
8310 while Homonym (C_E) /= E loop
8311 C_E := Homonym (C_E);
8314 Set_Homonym (C_E, S);
8318 Set_Current_Entity (S);
8323 if Is_Inherited_Operation (S) then
8324 Append_Inherited_Subprogram (S);
8326 Append_Entity (S, Current_Scope);
8329 Set_Public_Status (S);
8331 if Debug_Flag_E then
8332 Write_Str ("New overloaded entity chain: ");
8333 Write_Name (Chars (S));
8336 while Present (E) loop
8337 Write_Str (" "); Write_Int (Int (E));
8344 -- Generate warning for hiding
8347 and then Comes_From_Source (S)
8348 and then In_Extended_Main_Source_Unit (S)
8355 -- Warn unless genuine overloading. Do not emit warning on
8356 -- hiding predefined operators in Standard (these are either an
8357 -- (artifact of our implicit declarations, or simple noise) but
8358 -- keep warning on a operator defined on a local subtype, because
8359 -- of the real danger that different operators may be applied in
8360 -- various parts of the program.
8362 -- Note that if E and S have the same scope, there is never any
8363 -- hiding. Either the two conflict, and the program is illegal,
8364 -- or S is overriding an implicit inherited subprogram.
8366 if Scope (E) /= Scope (S)
8367 and then (not Is_Overloadable (E)
8368 or else Subtype_Conformant (E, S))
8369 and then (Is_Immediately_Visible (E)
8370 or else Is_Potentially_Use_Visible (S))
8372 if Scope (E) = Standard_Standard then
8373 if Nkind (S) = N_Defining_Operator_Symbol
8374 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8376 and then Matches_Predefined_Op
8379 ("declaration of & hides predefined operator?h?", S);
8382 -- E not immediately within Standard
8385 Error_Msg_Sloc := Sloc (E);
8386 Error_Msg_N ("declaration of & hides one #?h?", S);
8391 end Enter_Overloaded_Entity;
8393 -----------------------------
8394 -- Check_Untagged_Equality --
8395 -----------------------------
8397 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8398 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8399 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8403 -- This check applies only if we have a subprogram declaration with an
8404 -- untagged record type.
8406 if Nkind (Decl) /= N_Subprogram_Declaration
8407 or else not Is_Record_Type (Typ)
8408 or else Is_Tagged_Type (Typ)
8413 -- In Ada 2012 case, we will output errors or warnings depending on
8414 -- the setting of debug flag -gnatd.E.
8416 if Ada_Version >= Ada_2012 then
8417 Error_Msg_Warn := Debug_Flag_Dot_EE;
8419 -- In earlier versions of Ada, nothing to do unless we are warning on
8420 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8423 if not Warn_On_Ada_2012_Compatibility then
8428 -- Cases where the type has already been frozen
8430 if Is_Frozen (Typ) then
8432 -- If the type is not declared in a package, or if we are in the body
8433 -- of the package or in some other scope, the new operation is not
8434 -- primitive, and therefore legal, though suspicious. Should we
8435 -- generate a warning in this case ???
8437 if Ekind (Scope (Typ)) /= E_Package
8438 or else Scope (Typ) /= Current_Scope
8442 -- If the type is a generic actual (sub)type, the operation is not
8443 -- primitive either because the base type is declared elsewhere.
8445 elsif Is_Generic_Actual_Type (Typ) then
8448 -- Here we have a definite error of declaration after freezing
8451 if Ada_Version >= Ada_2012 then
8453 ("equality operator must be declared before type & is "
8454 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8456 -- In Ada 2012 mode with error turned to warning, output one
8457 -- more warning to warn that the equality operation may not
8458 -- compose. This is the consequence of ignoring the error.
8460 if Error_Msg_Warn then
8461 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8466 ("equality operator must be declared before type& is "
8467 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8470 -- If we are in the package body, we could just move the
8471 -- declaration to the package spec, so add a message saying that.
8473 if In_Package_Body (Scope (Typ)) then
8474 if Ada_Version >= Ada_2012 then
8476 ("\move declaration to package spec<<", Eq_Op);
8479 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8482 -- Otherwise try to find the freezing point
8485 Obj_Decl := Next (Parent (Typ));
8486 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8487 if Nkind (Obj_Decl) = N_Object_Declaration
8488 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8490 -- Freezing point, output warnings
8492 if Ada_Version >= Ada_2012 then
8494 ("type& is frozen by declaration??", Obj_Decl, Typ);
8496 ("\an equality operator cannot be declared after "
8501 ("type& is frozen by declaration (Ada 2012)?y?",
8504 ("\an equality operator cannot be declared after "
8505 & "this point (Ada 2012)?y?",
8517 -- Here if type is not frozen yet. It is illegal to have a primitive
8518 -- equality declared in the private part if the type is visible.
8520 elsif not In_Same_List (Parent (Typ), Decl)
8521 and then not Is_Limited_Type (Typ)
8523 -- Shouldn't we give an RM reference here???
8525 if Ada_Version >= Ada_2012 then
8527 ("equality operator appears too late<<", Eq_Op);
8530 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8533 -- No error detected
8538 end Check_Untagged_Equality;
8540 -----------------------------
8541 -- Find_Corresponding_Spec --
8542 -----------------------------
8544 function Find_Corresponding_Spec
8546 Post_Error : Boolean := True) return Entity_Id
8548 Spec : constant Node_Id := Specification (N);
8549 Designator : constant Entity_Id := Defining_Entity (Spec);
8553 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8554 -- Even if fully conformant, a body may depend on a generic actual when
8555 -- the spec does not, or vice versa, in which case they were distinct
8556 -- entities in the generic.
8558 -------------------------------
8559 -- Different_Generic_Profile --
8560 -------------------------------
8562 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8565 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8566 -- Check that the types of corresponding formals have the same
8567 -- generic actual if any. We have to account for subtypes of a
8568 -- generic formal, declared between a spec and a body, which may
8569 -- appear distinct in an instance but matched in the generic, and
8570 -- the subtype may be used either in the spec or the body of the
8571 -- subprogram being checked.
8573 -------------------------
8574 -- Same_Generic_Actual --
8575 -------------------------
8577 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8579 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8580 -- Predicate to check whether S1 is a subtype of S2 in the source
8583 -------------------------
8584 -- Is_Declared_Subtype --
8585 -------------------------
8587 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8589 return Comes_From_Source (Parent (S1))
8590 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8591 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8592 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8593 end Is_Declared_Subtype;
8595 -- Start of processing for Same_Generic_Actual
8598 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8599 or else Is_Declared_Subtype (T1, T2)
8600 or else Is_Declared_Subtype (T2, T1);
8601 end Same_Generic_Actual;
8603 -- Start of processing for Different_Generic_Profile
8606 if not In_Instance then
8609 elsif Ekind (E) = E_Function
8610 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8615 F1 := First_Formal (Designator);
8616 F2 := First_Formal (E);
8617 while Present (F1) loop
8618 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8627 end Different_Generic_Profile;
8629 -- Start of processing for Find_Corresponding_Spec
8632 E := Current_Entity (Designator);
8633 while Present (E) loop
8635 -- We are looking for a matching spec. It must have the same scope,
8636 -- and the same name, and either be type conformant, or be the case
8637 -- of a library procedure spec and its body (which belong to one
8638 -- another regardless of whether they are type conformant or not).
8640 if Scope (E) = Current_Scope then
8641 if Current_Scope = Standard_Standard
8642 or else (Ekind (E) = Ekind (Designator)
8643 and then Type_Conformant (E, Designator))
8645 -- Within an instantiation, we know that spec and body are
8646 -- subtype conformant, because they were subtype conformant in
8647 -- the generic. We choose the subtype-conformant entity here as
8648 -- well, to resolve spurious ambiguities in the instance that
8649 -- were not present in the generic (i.e. when two different
8650 -- types are given the same actual). If we are looking for a
8651 -- spec to match a body, full conformance is expected.
8655 -- Inherit the convention and "ghostness" of the matching
8656 -- spec to ensure proper full and subtype conformance.
8658 Set_Convention (Designator, Convention (E));
8660 -- Skip past subprogram bodies and subprogram renamings that
8661 -- may appear to have a matching spec, but that aren't fully
8662 -- conformant with it. That can occur in cases where an
8663 -- actual type causes unrelated homographs in the instance.
8665 if Nkind_In (N, N_Subprogram_Body,
8666 N_Subprogram_Renaming_Declaration)
8667 and then Present (Homonym (E))
8668 and then not Fully_Conformant (Designator, E)
8672 elsif not Subtype_Conformant (Designator, E) then
8675 elsif Different_Generic_Profile (E) then
8680 -- Ada 2012 (AI05-0165): For internally generated bodies of
8681 -- null procedures locate the internally generated spec. We
8682 -- enforce mode conformance since a tagged type may inherit
8683 -- from interfaces several null primitives which differ only
8684 -- in the mode of the formals.
8686 if not (Comes_From_Source (E))
8687 and then Is_Null_Procedure (E)
8688 and then not Mode_Conformant (Designator, E)
8692 -- For null procedures coming from source that are completions,
8693 -- analysis of the generated body will establish the link.
8695 elsif Comes_From_Source (E)
8696 and then Nkind (Spec) = N_Procedure_Specification
8697 and then Null_Present (Spec)
8701 -- Expression functions can be completions, but cannot be
8702 -- completed by an explicit body.
8704 elsif Comes_From_Source (E)
8705 and then Comes_From_Source (N)
8706 and then Nkind (N) = N_Subprogram_Body
8707 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8708 N_Expression_Function
8710 Error_Msg_Sloc := Sloc (E);
8711 Error_Msg_N ("body conflicts with expression function#", N);
8714 elsif not Has_Completion (E) then
8715 if Nkind (N) /= N_Subprogram_Body_Stub then
8716 Set_Corresponding_Spec (N, E);
8719 Set_Has_Completion (E);
8722 elsif Nkind (Parent (N)) = N_Subunit then
8724 -- If this is the proper body of a subunit, the completion
8725 -- flag is set when analyzing the stub.
8729 -- If E is an internal function with a controlling result that
8730 -- was created for an operation inherited by a null extension,
8731 -- it may be overridden by a body without a previous spec (one
8732 -- more reason why these should be shunned). In that case we
8733 -- remove the generated body if present, because the current
8734 -- one is the explicit overriding.
8736 elsif Ekind (E) = E_Function
8737 and then Ada_Version >= Ada_2005
8738 and then not Comes_From_Source (E)
8739 and then Has_Controlling_Result (E)
8740 and then Is_Null_Extension (Etype (E))
8741 and then Comes_From_Source (Spec)
8743 Set_Has_Completion (E, False);
8746 and then Nkind (Parent (E)) = N_Function_Specification
8749 (Unit_Declaration_Node
8750 (Corresponding_Body (Unit_Declaration_Node (E))));
8754 -- If expansion is disabled, or if the wrapper function has
8755 -- not been generated yet, this a late body overriding an
8756 -- inherited operation, or it is an overriding by some other
8757 -- declaration before the controlling result is frozen. In
8758 -- either case this is a declaration of a new entity.
8764 -- If the body already exists, then this is an error unless
8765 -- the previous declaration is the implicit declaration of a
8766 -- derived subprogram. It is also legal for an instance to
8767 -- contain type conformant overloadable declarations (but the
8768 -- generic declaration may not), per 8.3(26/2).
8770 elsif No (Alias (E))
8771 and then not Is_Intrinsic_Subprogram (E)
8772 and then not In_Instance
8775 Error_Msg_Sloc := Sloc (E);
8777 if Is_Imported (E) then
8779 ("body not allowed for imported subprogram & declared#",
8782 Error_Msg_NE ("duplicate body for & declared#", N, E);
8786 -- Child units cannot be overloaded, so a conformance mismatch
8787 -- between body and a previous spec is an error.
8789 elsif Is_Child_Unit (E)
8791 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8793 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8798 ("body of child unit does not match previous declaration", N);
8806 -- On exit, we know that no previous declaration of subprogram exists
8809 end Find_Corresponding_Spec;
8811 ----------------------
8812 -- Fully_Conformant --
8813 ----------------------
8815 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8818 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8820 end Fully_Conformant;
8822 ----------------------------------
8823 -- Fully_Conformant_Expressions --
8824 ----------------------------------
8826 function Fully_Conformant_Expressions
8827 (Given_E1 : Node_Id;
8828 Given_E2 : Node_Id) return Boolean
8830 E1 : constant Node_Id := Original_Node (Given_E1);
8831 E2 : constant Node_Id := Original_Node (Given_E2);
8832 -- We always test conformance on original nodes, since it is possible
8833 -- for analysis and/or expansion to make things look as though they
8834 -- conform when they do not, e.g. by converting 1+2 into 3.
8836 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8837 renames Fully_Conformant_Expressions;
8839 function FCL (L1, L2 : List_Id) return Boolean;
8840 -- Compare elements of two lists for conformance. Elements have to be
8841 -- conformant, and actuals inserted as default parameters do not match
8842 -- explicit actuals with the same value.
8844 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8845 -- Compare an operator node with a function call
8851 function FCL (L1, L2 : List_Id) return Boolean is
8855 if L1 = No_List then
8861 if L2 = No_List then
8867 -- Compare two lists, skipping rewrite insertions (we want to compare
8868 -- the original trees, not the expanded versions).
8871 if Is_Rewrite_Insertion (N1) then
8873 elsif Is_Rewrite_Insertion (N2) then
8879 elsif not FCE (N1, N2) then
8892 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8893 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8898 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8903 Act := First (Actuals);
8905 if Nkind (Op_Node) in N_Binary_Op then
8906 if not FCE (Left_Opnd (Op_Node), Act) then
8913 return Present (Act)
8914 and then FCE (Right_Opnd (Op_Node), Act)
8915 and then No (Next (Act));
8919 -- Start of processing for Fully_Conformant_Expressions
8922 -- Nonconformant if paren count does not match. Note: if some idiot
8923 -- complains that we don't do this right for more than 3 levels of
8924 -- parentheses, they will be treated with the respect they deserve.
8926 if Paren_Count (E1) /= Paren_Count (E2) then
8929 -- If same entities are referenced, then they are conformant even if
8930 -- they have different forms (RM 8.3.1(19-20)).
8932 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8933 if Present (Entity (E1)) then
8934 return Entity (E1) = Entity (E2)
8936 -- One may be a discriminant that has been replaced by the
8937 -- corresponding discriminal.
8940 (Chars (Entity (E1)) = Chars (Entity (E2))
8941 and then Ekind (Entity (E1)) = E_Discriminant
8942 and then Ekind (Entity (E2)) = E_In_Parameter)
8944 -- The discriminant of a protected type is transformed into
8945 -- a local constant and then into a parameter of a protected
8949 (Ekind (Entity (E1)) = E_Constant
8950 and then Ekind (Entity (E2)) = E_In_Parameter
8951 and then Present (Discriminal_Link (Entity (E1)))
8952 and then Discriminal_Link (Entity (E1)) =
8953 Discriminal_Link (Entity (E2)))
8955 -- AI12-050: The loop variables of quantified expressions
8956 -- match if they have the same identifier, even though they
8957 -- are different entities.
8960 (Chars (Entity (E1)) = Chars (Entity (E2))
8961 and then Ekind (Entity (E1)) = E_Loop_Parameter
8962 and then Ekind (Entity (E2)) = E_Loop_Parameter);
8964 elsif Nkind (E1) = N_Expanded_Name
8965 and then Nkind (E2) = N_Expanded_Name
8966 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8967 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8969 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8972 -- Identifiers in component associations don't always have
8973 -- entities, but their names must conform.
8975 return Nkind (E1) = N_Identifier
8976 and then Nkind (E2) = N_Identifier
8977 and then Chars (E1) = Chars (E2);
8980 elsif Nkind (E1) = N_Character_Literal
8981 and then Nkind (E2) = N_Expanded_Name
8983 return Nkind (Selector_Name (E2)) = N_Character_Literal
8984 and then Chars (E1) = Chars (Selector_Name (E2));
8986 elsif Nkind (E2) = N_Character_Literal
8987 and then Nkind (E1) = N_Expanded_Name
8989 return Nkind (Selector_Name (E1)) = N_Character_Literal
8990 and then Chars (E2) = Chars (Selector_Name (E1));
8992 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8993 return FCO (E1, E2);
8995 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8996 return FCO (E2, E1);
8998 -- Otherwise we must have the same syntactic entity
9000 elsif Nkind (E1) /= Nkind (E2) then
9003 -- At this point, we specialize by node type
9009 FCL (Expressions (E1), Expressions (E2))
9011 FCL (Component_Associations (E1),
9012 Component_Associations (E2));
9015 if Nkind (Expression (E1)) = N_Qualified_Expression
9017 Nkind (Expression (E2)) = N_Qualified_Expression
9019 return FCE (Expression (E1), Expression (E2));
9021 -- Check that the subtype marks and any constraints
9026 Indic1 : constant Node_Id := Expression (E1);
9027 Indic2 : constant Node_Id := Expression (E2);
9032 if Nkind (Indic1) /= N_Subtype_Indication then
9034 Nkind (Indic2) /= N_Subtype_Indication
9035 and then Entity (Indic1) = Entity (Indic2);
9037 elsif Nkind (Indic2) /= N_Subtype_Indication then
9039 Nkind (Indic1) /= N_Subtype_Indication
9040 and then Entity (Indic1) = Entity (Indic2);
9043 if Entity (Subtype_Mark (Indic1)) /=
9044 Entity (Subtype_Mark (Indic2))
9049 Elt1 := First (Constraints (Constraint (Indic1)));
9050 Elt2 := First (Constraints (Constraint (Indic2)));
9051 while Present (Elt1) and then Present (Elt2) loop
9052 if not FCE (Elt1, Elt2) then
9065 when N_Attribute_Reference =>
9067 Attribute_Name (E1) = Attribute_Name (E2)
9068 and then FCL (Expressions (E1), Expressions (E2));
9072 Entity (E1) = Entity (E2)
9073 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9074 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9076 when N_Membership_Test
9080 FCE (Left_Opnd (E1), Left_Opnd (E2))
9082 FCE (Right_Opnd (E1), Right_Opnd (E2));
9084 when N_Case_Expression =>
9090 if not FCE (Expression (E1), Expression (E2)) then
9094 Alt1 := First (Alternatives (E1));
9095 Alt2 := First (Alternatives (E2));
9097 if Present (Alt1) /= Present (Alt2) then
9099 elsif No (Alt1) then
9103 if not FCE (Expression (Alt1), Expression (Alt2))
9104 or else not FCL (Discrete_Choices (Alt1),
9105 Discrete_Choices (Alt2))
9116 when N_Character_Literal =>
9118 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9120 when N_Component_Association =>
9122 FCL (Choices (E1), Choices (E2))
9124 FCE (Expression (E1), Expression (E2));
9126 when N_Explicit_Dereference =>
9128 FCE (Prefix (E1), Prefix (E2));
9130 when N_Extension_Aggregate =>
9132 FCL (Expressions (E1), Expressions (E2))
9133 and then Null_Record_Present (E1) =
9134 Null_Record_Present (E2)
9135 and then FCL (Component_Associations (E1),
9136 Component_Associations (E2));
9138 when N_Function_Call =>
9140 FCE (Name (E1), Name (E2))
9142 FCL (Parameter_Associations (E1),
9143 Parameter_Associations (E2));
9145 when N_If_Expression =>
9147 FCL (Expressions (E1), Expressions (E2));
9149 when N_Indexed_Component =>
9151 FCE (Prefix (E1), Prefix (E2))
9153 FCL (Expressions (E1), Expressions (E2));
9155 when N_Integer_Literal =>
9156 return (Intval (E1) = Intval (E2));
9161 when N_Operator_Symbol =>
9163 Chars (E1) = Chars (E2);
9165 when N_Others_Choice =>
9168 when N_Parameter_Association =>
9170 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9171 and then FCE (Explicit_Actual_Parameter (E1),
9172 Explicit_Actual_Parameter (E2));
9174 when N_Qualified_Expression
9176 | N_Unchecked_Type_Conversion
9179 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9181 FCE (Expression (E1), Expression (E2));
9183 when N_Quantified_Expression =>
9184 if not FCE (Condition (E1), Condition (E2)) then
9188 if Present (Loop_Parameter_Specification (E1))
9189 and then Present (Loop_Parameter_Specification (E2))
9192 L1 : constant Node_Id :=
9193 Loop_Parameter_Specification (E1);
9194 L2 : constant Node_Id :=
9195 Loop_Parameter_Specification (E2);
9199 Reverse_Present (L1) = Reverse_Present (L2)
9201 FCE (Defining_Identifier (L1),
9202 Defining_Identifier (L2))
9204 FCE (Discrete_Subtype_Definition (L1),
9205 Discrete_Subtype_Definition (L2));
9208 elsif Present (Iterator_Specification (E1))
9209 and then Present (Iterator_Specification (E2))
9212 I1 : constant Node_Id := Iterator_Specification (E1);
9213 I2 : constant Node_Id := Iterator_Specification (E2);
9217 FCE (Defining_Identifier (I1),
9218 Defining_Identifier (I2))
9220 Of_Present (I1) = Of_Present (I2)
9222 Reverse_Present (I1) = Reverse_Present (I2)
9223 and then FCE (Name (I1), Name (I2))
9224 and then FCE (Subtype_Indication (I1),
9225 Subtype_Indication (I2));
9228 -- The quantified expressions used different specifications to
9229 -- walk their respective ranges.
9237 FCE (Low_Bound (E1), Low_Bound (E2))
9239 FCE (High_Bound (E1), High_Bound (E2));
9241 when N_Real_Literal =>
9242 return (Realval (E1) = Realval (E2));
9244 when N_Selected_Component =>
9246 FCE (Prefix (E1), Prefix (E2))
9248 FCE (Selector_Name (E1), Selector_Name (E2));
9252 FCE (Prefix (E1), Prefix (E2))
9254 FCE (Discrete_Range (E1), Discrete_Range (E2));
9256 when N_String_Literal =>
9258 S1 : constant String_Id := Strval (E1);
9259 S2 : constant String_Id := Strval (E2);
9260 L1 : constant Nat := String_Length (S1);
9261 L2 : constant Nat := String_Length (S2);
9268 for J in 1 .. L1 loop
9269 if Get_String_Char (S1, J) /=
9270 Get_String_Char (S2, J)
9282 Entity (E1) = Entity (E2)
9284 FCE (Right_Opnd (E1), Right_Opnd (E2));
9286 -- All other node types cannot appear in this context. Strictly
9287 -- we should raise a fatal internal error. Instead we just ignore
9288 -- the nodes. This means that if anyone makes a mistake in the
9289 -- expander and mucks an expression tree irretrievably, the result
9290 -- will be a failure to detect a (probably very obscure) case
9291 -- of non-conformance, which is better than bombing on some
9292 -- case where two expressions do in fact conform.
9298 end Fully_Conformant_Expressions;
9300 ----------------------------------------
9301 -- Fully_Conformant_Discrete_Subtypes --
9302 ----------------------------------------
9304 function Fully_Conformant_Discrete_Subtypes
9305 (Given_S1 : Node_Id;
9306 Given_S2 : Node_Id) return Boolean
9308 S1 : constant Node_Id := Original_Node (Given_S1);
9309 S2 : constant Node_Id := Original_Node (Given_S2);
9311 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9312 -- Special-case for a bound given by a discriminant, which in the body
9313 -- is replaced with the discriminal of the enclosing type.
9315 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9316 -- Check both bounds
9318 -----------------------
9319 -- Conforming_Bounds --
9320 -----------------------
9322 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9324 if Is_Entity_Name (B1)
9325 and then Is_Entity_Name (B2)
9326 and then Ekind (Entity (B1)) = E_Discriminant
9328 return Chars (B1) = Chars (B2);
9331 return Fully_Conformant_Expressions (B1, B2);
9333 end Conforming_Bounds;
9335 -----------------------
9336 -- Conforming_Ranges --
9337 -----------------------
9339 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9342 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9344 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9345 end Conforming_Ranges;
9347 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9350 if Nkind (S1) /= Nkind (S2) then
9353 elsif Is_Entity_Name (S1) then
9354 return Entity (S1) = Entity (S2);
9356 elsif Nkind (S1) = N_Range then
9357 return Conforming_Ranges (S1, S2);
9359 elsif Nkind (S1) = N_Subtype_Indication then
9361 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9364 (Range_Expression (Constraint (S1)),
9365 Range_Expression (Constraint (S2)));
9369 end Fully_Conformant_Discrete_Subtypes;
9371 --------------------
9372 -- Install_Entity --
9373 --------------------
9375 procedure Install_Entity (E : Entity_Id) is
9376 Prev : constant Entity_Id := Current_Entity (E);
9378 Set_Is_Immediately_Visible (E);
9379 Set_Current_Entity (E);
9380 Set_Homonym (E, Prev);
9383 ---------------------
9384 -- Install_Formals --
9385 ---------------------
9387 procedure Install_Formals (Id : Entity_Id) is
9390 F := First_Formal (Id);
9391 while Present (F) loop
9395 end Install_Formals;
9397 -----------------------------
9398 -- Is_Interface_Conformant --
9399 -----------------------------
9401 function Is_Interface_Conformant
9402 (Tagged_Type : Entity_Id;
9403 Iface_Prim : Entity_Id;
9404 Prim : Entity_Id) return Boolean
9406 -- The operation may in fact be an inherited (implicit) operation
9407 -- rather than the original interface primitive, so retrieve the
9408 -- ultimate ancestor.
9410 Iface : constant Entity_Id :=
9411 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9412 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9414 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9415 -- Return the controlling formal of Prim
9417 ------------------------
9418 -- Controlling_Formal --
9419 ------------------------
9421 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9425 E := First_Entity (Prim);
9426 while Present (E) loop
9427 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9435 end Controlling_Formal;
9439 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9440 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9442 -- Start of processing for Is_Interface_Conformant
9445 pragma Assert (Is_Subprogram (Iface_Prim)
9446 and then Is_Subprogram (Prim)
9447 and then Is_Dispatching_Operation (Iface_Prim)
9448 and then Is_Dispatching_Operation (Prim));
9450 pragma Assert (Is_Interface (Iface)
9451 or else (Present (Alias (Iface_Prim))
9454 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9456 if Prim = Iface_Prim
9457 or else not Is_Subprogram (Prim)
9458 or else Ekind (Prim) /= Ekind (Iface_Prim)
9459 or else not Is_Dispatching_Operation (Prim)
9460 or else Scope (Prim) /= Scope (Tagged_Type)
9462 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9463 or else not Primitive_Names_Match (Iface_Prim, Prim)
9467 -- The mode of the controlling formals must match
9469 elsif Present (Iface_Ctrl_F)
9470 and then Present (Prim_Ctrl_F)
9471 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9475 -- Case of a procedure, or a function whose result type matches the
9476 -- result type of the interface primitive, or a function that has no
9477 -- controlling result (I or access I).
9479 elsif Ekind (Iface_Prim) = E_Procedure
9480 or else Etype (Prim) = Etype (Iface_Prim)
9481 or else not Has_Controlling_Result (Prim)
9483 return Type_Conformant
9484 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9486 -- Case of a function returning an interface, or an access to one. Check
9487 -- that the return types correspond.
9489 elsif Implements_Interface (Typ, Iface) then
9490 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9492 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9497 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9498 Skip_Controlling_Formals => True);
9504 end Is_Interface_Conformant;
9506 ---------------------------------
9507 -- Is_Non_Overriding_Operation --
9508 ---------------------------------
9510 function Is_Non_Overriding_Operation
9511 (Prev_E : Entity_Id;
9512 New_E : Entity_Id) return Boolean
9516 G_Typ : Entity_Id := Empty;
9518 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9519 -- If F_Type is a derived type associated with a generic actual subtype,
9520 -- then return its Generic_Parent_Type attribute, else return Empty.
9522 function Types_Correspond
9523 (P_Type : Entity_Id;
9524 N_Type : Entity_Id) return Boolean;
9525 -- Returns true if and only if the types (or designated types in the
9526 -- case of anonymous access types) are the same or N_Type is derived
9527 -- directly or indirectly from P_Type.
9529 -----------------------------
9530 -- Get_Generic_Parent_Type --
9531 -----------------------------
9533 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9539 if Is_Derived_Type (F_Typ)
9540 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9542 -- The tree must be traversed to determine the parent subtype in
9543 -- the generic unit, which unfortunately isn't always available
9544 -- via semantic attributes. ??? (Note: The use of Original_Node
9545 -- is needed for cases where a full derived type has been
9548 -- If the parent type is a scalar type, the derivation creates
9549 -- an anonymous base type for it, and the source type is its
9552 if Is_Scalar_Type (F_Typ)
9553 and then not Comes_From_Source (F_Typ)
9557 (Original_Node (Parent (First_Subtype (F_Typ))));
9559 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9561 if Nkind (Defn) = N_Derived_Type_Definition then
9562 Indic := Subtype_Indication (Defn);
9564 if Nkind (Indic) = N_Subtype_Indication then
9565 G_Typ := Entity (Subtype_Mark (Indic));
9567 G_Typ := Entity (Indic);
9570 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9571 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9573 return Generic_Parent_Type (Parent (G_Typ));
9579 end Get_Generic_Parent_Type;
9581 ----------------------
9582 -- Types_Correspond --
9583 ----------------------
9585 function Types_Correspond
9586 (P_Type : Entity_Id;
9587 N_Type : Entity_Id) return Boolean
9589 Prev_Type : Entity_Id := Base_Type (P_Type);
9590 New_Type : Entity_Id := Base_Type (N_Type);
9593 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9594 Prev_Type := Designated_Type (Prev_Type);
9597 if Ekind (New_Type) = E_Anonymous_Access_Type then
9598 New_Type := Designated_Type (New_Type);
9601 if Prev_Type = New_Type then
9604 elsif not Is_Class_Wide_Type (New_Type) then
9605 while Etype (New_Type) /= New_Type loop
9606 New_Type := Etype (New_Type);
9608 if New_Type = Prev_Type then
9614 end Types_Correspond;
9616 -- Start of processing for Is_Non_Overriding_Operation
9619 -- In the case where both operations are implicit derived subprograms
9620 -- then neither overrides the other. This can only occur in certain
9621 -- obscure cases (e.g., derivation from homographs created in a generic
9624 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9627 elsif Ekind (Current_Scope) = E_Package
9628 and then Is_Generic_Instance (Current_Scope)
9629 and then In_Private_Part (Current_Scope)
9630 and then Comes_From_Source (New_E)
9632 -- We examine the formals and result type of the inherited operation,
9633 -- to determine whether their type is derived from (the instance of)
9634 -- a generic type. The first such formal or result type is the one
9637 Formal := First_Formal (Prev_E);
9639 while Present (Formal) loop
9640 F_Typ := Base_Type (Etype (Formal));
9642 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9643 F_Typ := Designated_Type (F_Typ);
9646 G_Typ := Get_Generic_Parent_Type (F_Typ);
9647 exit when Present (G_Typ);
9649 Next_Formal (Formal);
9652 -- If the function dispatches on result check the result type
9654 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9655 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9662 -- If the generic type is a private type, then the original operation
9663 -- was not overriding in the generic, because there was no primitive
9664 -- operation to override.
9666 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9667 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9668 N_Formal_Private_Type_Definition
9672 -- The generic parent type is the ancestor of a formal derived
9673 -- type declaration. We need to check whether it has a primitive
9674 -- operation that should be overridden by New_E in the generic.
9678 P_Formal : Entity_Id;
9679 N_Formal : Entity_Id;
9683 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9686 while Present (Prim_Elt) loop
9687 P_Prim := Node (Prim_Elt);
9689 if Chars (P_Prim) = Chars (New_E)
9690 and then Ekind (P_Prim) = Ekind (New_E)
9692 P_Formal := First_Formal (P_Prim);
9693 N_Formal := First_Formal (New_E);
9694 while Present (P_Formal) and then Present (N_Formal) loop
9695 P_Typ := Etype (P_Formal);
9696 N_Typ := Etype (N_Formal);
9698 if not Types_Correspond (P_Typ, N_Typ) then
9702 Next_Entity (P_Formal);
9703 Next_Entity (N_Formal);
9706 -- Found a matching primitive operation belonging to the
9707 -- formal ancestor type, so the new subprogram is
9711 and then No (N_Formal)
9712 and then (Ekind (New_E) /= E_Function
9715 (Etype (P_Prim), Etype (New_E)))
9721 Next_Elmt (Prim_Elt);
9724 -- If no match found, then the new subprogram does not override
9725 -- in the generic (nor in the instance).
9727 -- If the type in question is not abstract, and the subprogram
9728 -- is, this will be an error if the new operation is in the
9729 -- private part of the instance. Emit a warning now, which will
9730 -- make the subsequent error message easier to understand.
9732 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9733 and then Is_Abstract_Subprogram (Prev_E)
9734 and then In_Private_Part (Current_Scope)
9736 Error_Msg_Node_2 := F_Typ;
9738 ("private operation& in generic unit does not override "
9739 & "any primitive operation of& (RM 12.3 (18))??",
9749 end Is_Non_Overriding_Operation;
9751 -------------------------------------
9752 -- List_Inherited_Pre_Post_Aspects --
9753 -------------------------------------
9755 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9757 if Opt.List_Inherited_Aspects
9758 and then Is_Subprogram_Or_Generic_Subprogram (E)
9761 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9766 for Index in Subps'Range loop
9767 Items := Contract (Subps (Index));
9769 if Present (Items) then
9770 Prag := Pre_Post_Conditions (Items);
9771 while Present (Prag) loop
9772 Error_Msg_Sloc := Sloc (Prag);
9774 if Class_Present (Prag)
9775 and then not Split_PPC (Prag)
9777 if Pragma_Name (Prag) = Name_Precondition then
9779 ("info: & inherits `Pre''Class` aspect from "
9783 ("info: & inherits `Post''Class` aspect from "
9788 Prag := Next_Pragma (Prag);
9794 end List_Inherited_Pre_Post_Aspects;
9796 ------------------------------
9797 -- Make_Inequality_Operator --
9798 ------------------------------
9800 -- S is the defining identifier of an equality operator. We build a
9801 -- subprogram declaration with the right signature. This operation is
9802 -- intrinsic, because it is always expanded as the negation of the
9803 -- call to the equality function.
9805 procedure Make_Inequality_Operator (S : Entity_Id) is
9806 Loc : constant Source_Ptr := Sloc (S);
9809 Op_Name : Entity_Id;
9811 FF : constant Entity_Id := First_Formal (S);
9812 NF : constant Entity_Id := Next_Formal (FF);
9815 -- Check that equality was properly defined, ignore call if not
9822 A : constant Entity_Id :=
9823 Make_Defining_Identifier (Sloc (FF),
9824 Chars => Chars (FF));
9826 B : constant Entity_Id :=
9827 Make_Defining_Identifier (Sloc (NF),
9828 Chars => Chars (NF));
9831 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9833 Formals := New_List (
9834 Make_Parameter_Specification (Loc,
9835 Defining_Identifier => A,
9837 New_Occurrence_Of (Etype (First_Formal (S)),
9838 Sloc (Etype (First_Formal (S))))),
9840 Make_Parameter_Specification (Loc,
9841 Defining_Identifier => B,
9843 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9844 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9847 Make_Subprogram_Declaration (Loc,
9849 Make_Function_Specification (Loc,
9850 Defining_Unit_Name => Op_Name,
9851 Parameter_Specifications => Formals,
9852 Result_Definition =>
9853 New_Occurrence_Of (Standard_Boolean, Loc)));
9855 -- Insert inequality right after equality if it is explicit or after
9856 -- the derived type when implicit. These entities are created only
9857 -- for visibility purposes, and eventually replaced in the course
9858 -- of expansion, so they do not need to be attached to the tree and
9859 -- seen by the back-end. Keeping them internal also avoids spurious
9860 -- freezing problems. The declaration is inserted in the tree for
9861 -- analysis, and removed afterwards. If the equality operator comes
9862 -- from an explicit declaration, attach the inequality immediately
9863 -- after. Else the equality is inherited from a derived type
9864 -- declaration, so insert inequality after that declaration.
9866 if No (Alias (S)) then
9867 Insert_After (Unit_Declaration_Node (S), Decl);
9868 elsif Is_List_Member (Parent (S)) then
9869 Insert_After (Parent (S), Decl);
9871 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9874 Mark_Rewrite_Insertion (Decl);
9875 Set_Is_Intrinsic_Subprogram (Op_Name);
9878 Set_Has_Completion (Op_Name);
9879 Set_Corresponding_Equality (Op_Name, S);
9880 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9882 end Make_Inequality_Operator;
9884 ----------------------
9885 -- May_Need_Actuals --
9886 ----------------------
9888 procedure May_Need_Actuals (Fun : Entity_Id) is
9893 F := First_Formal (Fun);
9895 while Present (F) loop
9896 if No (Default_Value (F)) then
9904 Set_Needs_No_Actuals (Fun, B);
9905 end May_Need_Actuals;
9907 ---------------------
9908 -- Mode_Conformant --
9909 ---------------------
9911 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9914 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9916 end Mode_Conformant;
9918 ---------------------------
9919 -- New_Overloaded_Entity --
9920 ---------------------------
9922 procedure New_Overloaded_Entity
9924 Derived_Type : Entity_Id := Empty)
9926 Overridden_Subp : Entity_Id := Empty;
9927 -- Set if the current scope has an operation that is type-conformant
9928 -- with S, and becomes hidden by S.
9930 Is_Primitive_Subp : Boolean;
9931 -- Set to True if the new subprogram is primitive
9934 -- Entity that S overrides
9936 Prev_Vis : Entity_Id := Empty;
9937 -- Predecessor of E in Homonym chain
9939 procedure Check_For_Primitive_Subprogram
9940 (Is_Primitive : out Boolean;
9941 Is_Overriding : Boolean := False);
9942 -- If the subprogram being analyzed is a primitive operation of the type
9943 -- of a formal or result, set the Has_Primitive_Operations flag on the
9944 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9945 -- corresponding flag on the entity itself for later use.
9947 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9948 -- True if a) E is a subprogram whose first formal is a concurrent type
9949 -- defined in the scope of E that has some entry or subprogram whose
9950 -- profile matches E, or b) E is an internally built dispatching
9951 -- subprogram of a protected type and there is a matching subprogram
9952 -- defined in the enclosing scope of the protected type, or c) E is
9953 -- an entry of a synchronized type and a matching procedure has been
9954 -- previously defined in the enclosing scope of the synchronized type.
9956 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9957 -- Check that E is declared in the private part of the current package,
9958 -- or in the package body, where it may hide a previous declaration.
9959 -- We can't use In_Private_Part by itself because this flag is also
9960 -- set when freezing entities, so we must examine the place of the
9961 -- declaration in the tree, and recognize wrapper packages as well.
9963 function Is_Overriding_Alias
9965 New_E : Entity_Id) return Boolean;
9966 -- Check whether new subprogram and old subprogram are both inherited
9967 -- from subprograms that have distinct dispatch table entries. This can
9968 -- occur with derivations from instances with accidental homonyms. The
9969 -- function is conservative given that the converse is only true within
9970 -- instances that contain accidental overloadings.
9972 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9973 -- Report conflict between entities S and E
9975 ------------------------------------
9976 -- Check_For_Primitive_Subprogram --
9977 ------------------------------------
9979 procedure Check_For_Primitive_Subprogram
9980 (Is_Primitive : out Boolean;
9981 Is_Overriding : Boolean := False)
9987 function Visible_Part_Type (T : Entity_Id) return Boolean;
9988 -- Returns true if T is declared in the visible part of the current
9989 -- package scope; otherwise returns false. Assumes that T is declared
9992 procedure Check_Private_Overriding (T : Entity_Id);
9993 -- Checks that if a primitive abstract subprogram of a visible
9994 -- abstract type is declared in a private part, then it must override
9995 -- an abstract subprogram declared in the visible part. Also checks
9996 -- that if a primitive function with a controlling result is declared
9997 -- in a private part, then it must override a function declared in
9998 -- the visible part.
10000 ------------------------------
10001 -- Check_Private_Overriding --
10002 ------------------------------
10004 procedure Check_Private_Overriding (T : Entity_Id) is
10005 function Overrides_Private_Part_Op return Boolean;
10006 -- This detects the special case where the overriding subprogram
10007 -- is overriding a subprogram that was declared in the same
10008 -- private part. That case is illegal by 3.9.3(10).
10010 function Overrides_Visible_Function
10011 (Partial_View : Entity_Id) return Boolean;
10012 -- True if S overrides a function in the visible part. The
10013 -- overridden function could be explicitly or implicitly declared.
10015 -------------------------------
10016 -- Overrides_Private_Part_Op --
10017 -------------------------------
10019 function Overrides_Private_Part_Op return Boolean is
10020 Over_Decl : constant Node_Id :=
10021 Unit_Declaration_Node (Overridden_Operation (S));
10022 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10025 pragma Assert (Is_Overriding);
10027 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10029 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10031 return In_Same_List (Over_Decl, Subp_Decl);
10032 end Overrides_Private_Part_Op;
10034 --------------------------------
10035 -- Overrides_Visible_Function --
10036 --------------------------------
10038 function Overrides_Visible_Function
10039 (Partial_View : Entity_Id) return Boolean
10042 if not Is_Overriding or else not Has_Homonym (S) then
10046 if not Present (Partial_View) then
10050 -- Search through all the homonyms H of S in the current
10051 -- package spec, and return True if we find one that matches.
10052 -- Note that Parent (H) will be the declaration of the
10053 -- partial view of T for a match.
10056 H : Entity_Id := S;
10060 exit when not Present (H) or else Scope (H) /= Scope (S);
10064 N_Private_Extension_Declaration,
10065 N_Private_Type_Declaration)
10066 and then Defining_Identifier (Parent (H)) = Partial_View
10074 end Overrides_Visible_Function;
10076 -- Start of processing for Check_Private_Overriding
10079 if Is_Package_Or_Generic_Package (Current_Scope)
10080 and then In_Private_Part (Current_Scope)
10081 and then Visible_Part_Type (T)
10082 and then not In_Instance
10084 if Is_Abstract_Type (T)
10085 and then Is_Abstract_Subprogram (S)
10086 and then (not Is_Overriding
10087 or else not Is_Abstract_Subprogram (E)
10088 or else Overrides_Private_Part_Op)
10091 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10094 elsif Ekind (S) = E_Function then
10096 Partial_View : constant Entity_Id :=
10097 Incomplete_Or_Partial_View (T);
10100 if not Overrides_Visible_Function (Partial_View) then
10102 -- Here, S is "function ... return T;" declared in
10103 -- the private part, not overriding some visible
10104 -- operation. That's illegal in the tagged case
10105 -- (but not if the private type is untagged).
10107 if ((Present (Partial_View)
10108 and then Is_Tagged_Type (Partial_View))
10109 or else (not Present (Partial_View)
10110 and then Is_Tagged_Type (T)))
10111 and then T = Base_Type (Etype (S))
10114 ("private function with tagged result must"
10115 & " override visible-part function", S);
10117 ("\move subprogram to the visible part"
10118 & " (RM 3.9.3(10))", S);
10120 -- AI05-0073: extend this test to the case of a
10121 -- function with a controlling access result.
10123 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10124 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10126 not Is_Class_Wide_Type
10127 (Designated_Type (Etype (S)))
10128 and then Ada_Version >= Ada_2012
10131 ("private function with controlling access "
10132 & "result must override visible-part function",
10135 ("\move subprogram to the visible part"
10136 & " (RM 3.9.3(10))", S);
10142 end Check_Private_Overriding;
10144 -----------------------
10145 -- Visible_Part_Type --
10146 -----------------------
10148 function Visible_Part_Type (T : Entity_Id) return Boolean is
10149 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10152 -- If the entity is a private type, then it must be declared in a
10155 if Ekind (T) in Private_Kind then
10158 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10161 elsif Is_List_Member (Declaration_Node (T))
10162 and then List_Containing (Declaration_Node (T)) =
10163 Visible_Declarations (Specification (P))
10170 end Visible_Part_Type;
10172 -- Start of processing for Check_For_Primitive_Subprogram
10175 Is_Primitive := False;
10177 if not Comes_From_Source (S) then
10180 -- If subprogram is at library level, it is not primitive operation
10182 elsif Current_Scope = Standard_Standard then
10185 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10186 and then not In_Package_Body (Current_Scope))
10187 or else Is_Overriding
10189 -- For function, check return type
10191 if Ekind (S) = E_Function then
10192 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10193 F_Typ := Designated_Type (Etype (S));
10195 F_Typ := Etype (S);
10198 B_Typ := Base_Type (F_Typ);
10200 if Scope (B_Typ) = Current_Scope
10201 and then not Is_Class_Wide_Type (B_Typ)
10202 and then not Is_Generic_Type (B_Typ)
10204 Is_Primitive := True;
10205 Set_Has_Primitive_Operations (B_Typ);
10206 Set_Is_Primitive (S);
10207 Check_Private_Overriding (B_Typ);
10209 -- The Ghost policy in effect at the point of declaration
10210 -- or a tagged type and a primitive operation must match
10211 -- (SPARK RM 6.9(16)).
10213 Check_Ghost_Primitive (S, B_Typ);
10217 -- For all subprograms, check formals
10219 Formal := First_Formal (S);
10220 while Present (Formal) loop
10221 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10222 F_Typ := Designated_Type (Etype (Formal));
10224 F_Typ := Etype (Formal);
10227 B_Typ := Base_Type (F_Typ);
10229 if Ekind (B_Typ) = E_Access_Subtype then
10230 B_Typ := Base_Type (B_Typ);
10233 if Scope (B_Typ) = Current_Scope
10234 and then not Is_Class_Wide_Type (B_Typ)
10235 and then not Is_Generic_Type (B_Typ)
10237 Is_Primitive := True;
10238 Set_Is_Primitive (S);
10239 Set_Has_Primitive_Operations (B_Typ);
10240 Check_Private_Overriding (B_Typ);
10242 -- The Ghost policy in effect at the point of declaration
10243 -- of a tagged type and a primitive operation must match
10244 -- (SPARK RM 6.9(16)).
10246 Check_Ghost_Primitive (S, B_Typ);
10249 Next_Formal (Formal);
10252 -- Special case: An equality function can be redefined for a type
10253 -- occurring in a declarative part, and won't otherwise be treated as
10254 -- a primitive because it doesn't occur in a package spec and doesn't
10255 -- override an inherited subprogram. It's important that we mark it
10256 -- primitive so it can be returned by Collect_Primitive_Operations
10257 -- and be used in composing the equality operation of later types
10258 -- that have a component of the type.
10260 elsif Chars (S) = Name_Op_Eq
10261 and then Etype (S) = Standard_Boolean
10263 B_Typ := Base_Type (Etype (First_Formal (S)));
10265 if Scope (B_Typ) = Current_Scope
10267 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10268 and then not Is_Limited_Type (B_Typ)
10270 Is_Primitive := True;
10271 Set_Is_Primitive (S);
10272 Set_Has_Primitive_Operations (B_Typ);
10273 Check_Private_Overriding (B_Typ);
10275 -- The Ghost policy in effect at the point of declaration of a
10276 -- tagged type and a primitive operation must match
10277 -- (SPARK RM 6.9(16)).
10279 Check_Ghost_Primitive (S, B_Typ);
10282 end Check_For_Primitive_Subprogram;
10284 --------------------------------------
10285 -- Has_Matching_Entry_Or_Subprogram --
10286 --------------------------------------
10288 function Has_Matching_Entry_Or_Subprogram
10289 (E : Entity_Id) return Boolean
10291 function Check_Conforming_Parameters
10292 (E1_Param : Node_Id;
10293 E2_Param : Node_Id) return Boolean;
10294 -- Starting from the given parameters, check that all the parameters
10295 -- of two entries or subprograms are subtype conformant. Used to skip
10296 -- the check on the controlling argument.
10298 function Matching_Entry_Or_Subprogram
10299 (Conc_Typ : Entity_Id;
10300 Subp : Entity_Id) return Entity_Id;
10301 -- Return the first entry or subprogram of the given concurrent type
10302 -- whose name matches the name of Subp and has a profile conformant
10303 -- with Subp; return Empty if not found.
10305 function Matching_Dispatching_Subprogram
10306 (Conc_Typ : Entity_Id;
10307 Ent : Entity_Id) return Entity_Id;
10308 -- Return the first dispatching primitive of Conc_Type defined in the
10309 -- enclosing scope of Conc_Type (i.e. before the full definition of
10310 -- this concurrent type) whose name matches the entry Ent and has a
10311 -- profile conformant with the profile of the corresponding (not yet
10312 -- built) dispatching primitive of Ent; return Empty if not found.
10314 function Matching_Original_Protected_Subprogram
10315 (Prot_Typ : Entity_Id;
10316 Subp : Entity_Id) return Entity_Id;
10317 -- Return the first subprogram defined in the enclosing scope of
10318 -- Prot_Typ (before the full definition of this protected type)
10319 -- whose name matches the original name of Subp and has a profile
10320 -- conformant with the profile of Subp; return Empty if not found.
10322 ---------------------------------
10323 -- Check_Confirming_Parameters --
10324 ---------------------------------
10326 function Check_Conforming_Parameters
10327 (E1_Param : Node_Id;
10328 E2_Param : Node_Id) return Boolean
10330 Param_E1 : Node_Id := E1_Param;
10331 Param_E2 : Node_Id := E2_Param;
10334 while Present (Param_E1) and then Present (Param_E2) loop
10335 if Ekind (Defining_Identifier (Param_E1)) /=
10336 Ekind (Defining_Identifier (Param_E2))
10339 (Find_Parameter_Type (Param_E1),
10340 Find_Parameter_Type (Param_E2),
10341 Subtype_Conformant)
10350 -- The candidate is not valid if one of the two lists contains
10351 -- more parameters than the other
10353 return No (Param_E1) and then No (Param_E2);
10354 end Check_Conforming_Parameters;
10356 ----------------------------------
10357 -- Matching_Entry_Or_Subprogram --
10358 ----------------------------------
10360 function Matching_Entry_Or_Subprogram
10361 (Conc_Typ : Entity_Id;
10362 Subp : Entity_Id) return Entity_Id
10367 E := First_Entity (Conc_Typ);
10368 while Present (E) loop
10369 if Chars (Subp) = Chars (E)
10370 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10372 Check_Conforming_Parameters
10373 (First (Parameter_Specifications (Parent (E))),
10374 Next (First (Parameter_Specifications (Parent (Subp)))))
10383 end Matching_Entry_Or_Subprogram;
10385 -------------------------------------
10386 -- Matching_Dispatching_Subprogram --
10387 -------------------------------------
10389 function Matching_Dispatching_Subprogram
10390 (Conc_Typ : Entity_Id;
10391 Ent : Entity_Id) return Entity_Id
10396 -- Search for entities in the enclosing scope of this synchonized
10399 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10400 Push_Scope (Scope (Conc_Typ));
10401 E := Current_Entity_In_Scope (Ent);
10404 while Present (E) loop
10405 if Scope (E) = Scope (Conc_Typ)
10406 and then Comes_From_Source (E)
10407 and then Ekind (E) = E_Procedure
10408 and then Present (First_Entity (E))
10409 and then Is_Controlling_Formal (First_Entity (E))
10410 and then Etype (First_Entity (E)) = Conc_Typ
10412 Check_Conforming_Parameters
10413 (First (Parameter_Specifications (Parent (Ent))),
10414 Next (First (Parameter_Specifications (Parent (E)))))
10423 end Matching_Dispatching_Subprogram;
10425 --------------------------------------------
10426 -- Matching_Original_Protected_Subprogram --
10427 --------------------------------------------
10429 function Matching_Original_Protected_Subprogram
10430 (Prot_Typ : Entity_Id;
10431 Subp : Entity_Id) return Entity_Id
10433 ICF : constant Boolean :=
10434 Is_Controlling_Formal (First_Entity (Subp));
10438 -- Temporarily decorate the first parameter of Subp as controlling
10439 -- formal, required to invoke Subtype_Conformant.
10441 Set_Is_Controlling_Formal (First_Entity (Subp));
10444 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10446 while Present (E) loop
10447 if Scope (E) = Scope (Prot_Typ)
10448 and then Comes_From_Source (E)
10449 and then Ekind (Subp) = Ekind (E)
10450 and then Present (First_Entity (E))
10451 and then Is_Controlling_Formal (First_Entity (E))
10452 and then Etype (First_Entity (E)) = Prot_Typ
10453 and then Subtype_Conformant (Subp, E,
10454 Skip_Controlling_Formals => True)
10456 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10463 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10466 end Matching_Original_Protected_Subprogram;
10468 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10471 -- Case 1: E is a subprogram whose first formal is a concurrent type
10472 -- defined in the scope of E that has an entry or subprogram whose
10473 -- profile matches E.
10475 if Comes_From_Source (E)
10476 and then Is_Subprogram (E)
10477 and then Present (First_Entity (E))
10478 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10481 Scope (Corresponding_Concurrent_Type
10482 (Etype (First_Entity (E))))
10485 (Matching_Entry_Or_Subprogram
10486 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10489 Report_Conflict (E,
10490 Matching_Entry_Or_Subprogram
10491 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10496 -- Case 2: E is an internally built dispatching subprogram of a
10497 -- protected type and there is a subprogram defined in the enclosing
10498 -- scope of the protected type that has the original name of E and
10499 -- its profile is conformant with the profile of E. We check the
10500 -- name of the original protected subprogram associated with E since
10501 -- the expander builds dispatching primitives of protected functions
10502 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10504 elsif not Comes_From_Source (E)
10505 and then Is_Subprogram (E)
10506 and then Present (First_Entity (E))
10507 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10508 and then Present (Original_Protected_Subprogram (E))
10511 (Matching_Original_Protected_Subprogram
10512 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10515 Report_Conflict (E,
10516 Matching_Original_Protected_Subprogram
10517 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10521 -- Case 3: E is an entry of a synchronized type and a matching
10522 -- procedure has been previously defined in the enclosing scope
10523 -- of the synchronized type.
10525 elsif Comes_From_Source (E)
10526 and then Ekind (E) = E_Entry
10528 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10530 Report_Conflict (E,
10531 Matching_Dispatching_Subprogram (Current_Scope, E));
10536 end Has_Matching_Entry_Or_Subprogram;
10538 ----------------------------
10539 -- Is_Private_Declaration --
10540 ----------------------------
10542 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10543 Decl : constant Node_Id := Unit_Declaration_Node (E);
10544 Priv_Decls : List_Id;
10547 if Is_Package_Or_Generic_Package (Current_Scope)
10548 and then In_Private_Part (Current_Scope)
10551 Private_Declarations (Package_Specification (Current_Scope));
10553 return In_Package_Body (Current_Scope)
10555 (Is_List_Member (Decl)
10556 and then List_Containing (Decl) = Priv_Decls)
10557 or else (Nkind (Parent (Decl)) = N_Package_Specification
10559 Is_Compilation_Unit
10560 (Defining_Entity (Parent (Decl)))
10561 and then List_Containing (Parent (Parent (Decl))) =
10566 end Is_Private_Declaration;
10568 --------------------------
10569 -- Is_Overriding_Alias --
10570 --------------------------
10572 function Is_Overriding_Alias
10573 (Old_E : Entity_Id;
10574 New_E : Entity_Id) return Boolean
10576 AO : constant Entity_Id := Alias (Old_E);
10577 AN : constant Entity_Id := Alias (New_E);
10580 return Scope (AO) /= Scope (AN)
10581 or else No (DTC_Entity (AO))
10582 or else No (DTC_Entity (AN))
10583 or else DT_Position (AO) = DT_Position (AN);
10584 end Is_Overriding_Alias;
10586 ---------------------
10587 -- Report_Conflict --
10588 ---------------------
10590 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10592 Error_Msg_Sloc := Sloc (E);
10594 -- Generate message, with useful additional warning if in generic
10596 if Is_Generic_Unit (E) then
10597 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10598 Error_Msg_N ("\& conflicts with declaration#", S);
10600 Error_Msg_N ("& conflicts with declaration#", S);
10602 end Report_Conflict;
10604 -- Start of processing for New_Overloaded_Entity
10607 -- We need to look for an entity that S may override. This must be a
10608 -- homonym in the current scope, so we look for the first homonym of
10609 -- S in the current scope as the starting point for the search.
10611 E := Current_Entity_In_Scope (S);
10613 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10614 -- They are directly added to the list of primitive operations of
10615 -- Derived_Type, unless this is a rederivation in the private part
10616 -- of an operation that was already derived in the visible part of
10617 -- the current package.
10619 if Ada_Version >= Ada_2005
10620 and then Present (Derived_Type)
10621 and then Present (Alias (S))
10622 and then Is_Dispatching_Operation (Alias (S))
10623 and then Present (Find_Dispatching_Type (Alias (S)))
10624 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10626 -- For private types, when the full-view is processed we propagate to
10627 -- the full view the non-overridden entities whose attribute "alias"
10628 -- references an interface primitive. These entities were added by
10629 -- Derive_Subprograms to ensure that interface primitives are
10632 -- Inside_Freeze_Actions is non zero when S corresponds with an
10633 -- internal entity that links an interface primitive with its
10634 -- covering primitive through attribute Interface_Alias (see
10635 -- Add_Internal_Interface_Entities).
10637 if Inside_Freezing_Actions = 0
10638 and then Is_Package_Or_Generic_Package (Current_Scope)
10639 and then In_Private_Part (Current_Scope)
10640 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10641 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10642 and then Full_View (Defining_Identifier (Parent (E)))
10643 = Defining_Identifier (Parent (S))
10644 and then Alias (E) = Alias (S)
10646 Check_Operation_From_Private_View (S, E);
10647 Set_Is_Dispatching_Operation (S);
10652 Enter_Overloaded_Entity (S);
10653 Check_Dispatching_Operation (S, Empty);
10654 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10660 -- For synchronized types check conflicts of this entity with previously
10661 -- defined entities.
10663 if Ada_Version >= Ada_2005
10664 and then Has_Matching_Entry_Or_Subprogram (S)
10669 -- If there is no homonym then this is definitely not overriding
10672 Enter_Overloaded_Entity (S);
10673 Check_Dispatching_Operation (S, Empty);
10674 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10676 -- If subprogram has an explicit declaration, check whether it has an
10677 -- overriding indicator.
10679 if Comes_From_Source (S) then
10680 Check_Synchronized_Overriding (S, Overridden_Subp);
10682 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10683 -- it may have overridden some hidden inherited primitive. Update
10684 -- Overridden_Subp to avoid spurious errors when checking the
10685 -- overriding indicator.
10687 if Ada_Version >= Ada_2012
10688 and then No (Overridden_Subp)
10689 and then Is_Dispatching_Operation (S)
10690 and then Present (Overridden_Operation (S))
10692 Overridden_Subp := Overridden_Operation (S);
10695 Check_Overriding_Indicator
10696 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10698 -- The Ghost policy in effect at the point of declaration of a
10699 -- parent subprogram and an overriding subprogram must match
10700 -- (SPARK RM 6.9(17)).
10702 Check_Ghost_Overriding (S, Overridden_Subp);
10705 -- If there is a homonym that is not overloadable, then we have an
10706 -- error, except for the special cases checked explicitly below.
10708 elsif not Is_Overloadable (E) then
10710 -- Check for spurious conflict produced by a subprogram that has the
10711 -- same name as that of the enclosing generic package. The conflict
10712 -- occurs within an instance, between the subprogram and the renaming
10713 -- declaration for the package. After the subprogram, the package
10714 -- renaming declaration becomes hidden.
10716 if Ekind (E) = E_Package
10717 and then Present (Renamed_Object (E))
10718 and then Renamed_Object (E) = Current_Scope
10719 and then Nkind (Parent (Renamed_Object (E))) =
10720 N_Package_Specification
10721 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10724 Set_Is_Immediately_Visible (E, False);
10725 Enter_Overloaded_Entity (S);
10726 Set_Homonym (S, Homonym (E));
10727 Check_Dispatching_Operation (S, Empty);
10728 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10730 -- If the subprogram is implicit it is hidden by the previous
10731 -- declaration. However if it is dispatching, it must appear in the
10732 -- dispatch table anyway, because it can be dispatched to even if it
10733 -- cannot be called directly.
10735 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10736 Set_Scope (S, Current_Scope);
10738 if Is_Dispatching_Operation (Alias (S)) then
10739 Check_Dispatching_Operation (S, Empty);
10745 Report_Conflict (S, E);
10749 -- E exists and is overloadable
10752 Check_Synchronized_Overriding (S, Overridden_Subp);
10754 -- Loop through E and its homonyms to determine if any of them is
10755 -- the candidate for overriding by S.
10757 while Present (E) loop
10759 -- Definitely not interesting if not in the current scope
10761 if Scope (E) /= Current_Scope then
10764 -- A function can overload the name of an abstract state. The
10765 -- state can be viewed as a function with a profile that cannot
10766 -- be matched by anything.
10768 elsif Ekind (S) = E_Function
10769 and then Ekind (E) = E_Abstract_State
10771 Enter_Overloaded_Entity (S);
10774 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10775 -- procedures locate the internally generated spec. We enforce
10776 -- mode conformance since a tagged type may inherit from
10777 -- interfaces several null primitives which differ only in
10778 -- the mode of the formals.
10780 elsif not Comes_From_Source (S)
10781 and then Is_Null_Procedure (S)
10782 and then not Mode_Conformant (E, S)
10786 -- Check if we have type conformance
10788 elsif Type_Conformant (E, S) then
10790 -- If the old and new entities have the same profile and one
10791 -- is not the body of the other, then this is an error, unless
10792 -- one of them is implicitly declared.
10794 -- There are some cases when both can be implicit, for example
10795 -- when both a literal and a function that overrides it are
10796 -- inherited in a derivation, or when an inherited operation
10797 -- of a tagged full type overrides the inherited operation of
10798 -- a private extension. Ada 83 had a special rule for the
10799 -- literal case. In Ada 95, the later implicit operation hides
10800 -- the former, and the literal is always the former. In the
10801 -- odd case where both are derived operations declared at the
10802 -- same point, both operations should be declared, and in that
10803 -- case we bypass the following test and proceed to the next
10804 -- part. This can only occur for certain obscure cases in
10805 -- instances, when an operation on a type derived from a formal
10806 -- private type does not override a homograph inherited from
10807 -- the actual. In subsequent derivations of such a type, the
10808 -- DT positions of these operations remain distinct, if they
10811 if Present (Alias (S))
10812 and then (No (Alias (E))
10813 or else Comes_From_Source (E)
10814 or else Is_Abstract_Subprogram (S)
10816 (Is_Dispatching_Operation (E)
10817 and then Is_Overriding_Alias (E, S)))
10818 and then Ekind (E) /= E_Enumeration_Literal
10820 -- When an derived operation is overloaded it may be due to
10821 -- the fact that the full view of a private extension
10822 -- re-inherits. It has to be dealt with.
10824 if Is_Package_Or_Generic_Package (Current_Scope)
10825 and then In_Private_Part (Current_Scope)
10827 Check_Operation_From_Private_View (S, E);
10830 -- In any case the implicit operation remains hidden by the
10831 -- existing declaration, which is overriding. Indicate that
10832 -- E overrides the operation from which S is inherited.
10834 if Present (Alias (S)) then
10835 Set_Overridden_Operation (E, Alias (S));
10836 Inherit_Subprogram_Contract (E, Alias (S));
10839 Set_Overridden_Operation (E, S);
10840 Inherit_Subprogram_Contract (E, S);
10843 if Comes_From_Source (E) then
10844 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10846 -- The Ghost policy in effect at the point of declaration
10847 -- of a parent subprogram and an overriding subprogram
10848 -- must match (SPARK RM 6.9(17)).
10850 Check_Ghost_Overriding (E, S);
10855 -- Within an instance, the renaming declarations for actual
10856 -- subprograms may become ambiguous, but they do not hide each
10859 elsif Ekind (E) /= E_Entry
10860 and then not Comes_From_Source (E)
10861 and then not Is_Generic_Instance (E)
10862 and then (Present (Alias (E))
10863 or else Is_Intrinsic_Subprogram (E))
10864 and then (not In_Instance
10865 or else No (Parent (E))
10866 or else Nkind (Unit_Declaration_Node (E)) /=
10867 N_Subprogram_Renaming_Declaration)
10869 -- A subprogram child unit is not allowed to override an
10870 -- inherited subprogram (10.1.1(20)).
10872 if Is_Child_Unit (S) then
10874 ("child unit overrides inherited subprogram in parent",
10879 if Is_Non_Overriding_Operation (E, S) then
10880 Enter_Overloaded_Entity (S);
10882 if No (Derived_Type)
10883 or else Is_Tagged_Type (Derived_Type)
10885 Check_Dispatching_Operation (S, Empty);
10891 -- E is a derived operation or an internal operator which
10892 -- is being overridden. Remove E from further visibility.
10893 -- Furthermore, if E is a dispatching operation, it must be
10894 -- replaced in the list of primitive operations of its type
10895 -- (see Override_Dispatching_Operation).
10897 Overridden_Subp := E;
10903 Prev := First_Entity (Current_Scope);
10904 while Present (Prev) and then Next_Entity (Prev) /= E loop
10905 Next_Entity (Prev);
10908 -- It is possible for E to be in the current scope and
10909 -- yet not in the entity chain. This can only occur in a
10910 -- generic context where E is an implicit concatenation
10911 -- in the formal part, because in a generic body the
10912 -- entity chain starts with the formals.
10914 -- In GNATprove mode, a wrapper for an operation with
10915 -- axiomatization may be a homonym of another declaration
10916 -- for an actual subprogram (needs refinement ???).
10920 and then GNATprove_Mode
10922 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10923 N_Subprogram_Renaming_Declaration
10927 pragma Assert (Chars (E) = Name_Op_Concat);
10932 -- E must be removed both from the entity_list of the
10933 -- current scope, and from the visibility chain.
10935 if Debug_Flag_E then
10936 Write_Str ("Override implicit operation ");
10937 Write_Int (Int (E));
10941 -- If E is a predefined concatenation, it stands for four
10942 -- different operations. As a result, a single explicit
10943 -- declaration does not hide it. In a possible ambiguous
10944 -- situation, Disambiguate chooses the user-defined op,
10945 -- so it is correct to retain the previous internal one.
10947 if Chars (E) /= Name_Op_Concat
10948 or else Ekind (E) /= E_Operator
10950 -- For nondispatching derived operations that are
10951 -- overridden by a subprogram declared in the private
10952 -- part of a package, we retain the derived subprogram
10953 -- but mark it as not immediately visible. If the
10954 -- derived operation was declared in the visible part
10955 -- then this ensures that it will still be visible
10956 -- outside the package with the proper signature
10957 -- (calls from outside must also be directed to this
10958 -- version rather than the overriding one, unlike the
10959 -- dispatching case). Calls from inside the package
10960 -- will still resolve to the overriding subprogram
10961 -- since the derived one is marked as not visible
10962 -- within the package.
10964 -- If the private operation is dispatching, we achieve
10965 -- the overriding by keeping the implicit operation
10966 -- but setting its alias to be the overriding one. In
10967 -- this fashion the proper body is executed in all
10968 -- cases, but the original signature is used outside
10971 -- If the overriding is not in the private part, we
10972 -- remove the implicit operation altogether.
10974 if Is_Private_Declaration (S) then
10975 if not Is_Dispatching_Operation (E) then
10976 Set_Is_Immediately_Visible (E, False);
10978 -- Work done in Override_Dispatching_Operation,
10979 -- so nothing else needs to be done here.
10985 -- Find predecessor of E in Homonym chain
10987 if E = Current_Entity (E) then
10990 Prev_Vis := Current_Entity (E);
10991 while Homonym (Prev_Vis) /= E loop
10992 Prev_Vis := Homonym (Prev_Vis);
10996 if Prev_Vis /= Empty then
10998 -- Skip E in the visibility chain
11000 Set_Homonym (Prev_Vis, Homonym (E));
11003 Set_Name_Entity_Id (Chars (E), Homonym (E));
11006 Set_Next_Entity (Prev, Next_Entity (E));
11008 if No (Next_Entity (Prev)) then
11009 Set_Last_Entity (Current_Scope, Prev);
11014 Enter_Overloaded_Entity (S);
11016 -- For entities generated by Derive_Subprograms the
11017 -- overridden operation is the inherited primitive
11018 -- (which is available through the attribute alias).
11020 if not (Comes_From_Source (E))
11021 and then Is_Dispatching_Operation (E)
11022 and then Find_Dispatching_Type (E) =
11023 Find_Dispatching_Type (S)
11024 and then Present (Alias (E))
11025 and then Comes_From_Source (Alias (E))
11027 Set_Overridden_Operation (S, Alias (E));
11028 Inherit_Subprogram_Contract (S, Alias (E));
11030 -- Normal case of setting entity as overridden
11032 -- Note: Static_Initialization and Overridden_Operation
11033 -- attributes use the same field in subprogram entities.
11034 -- Static_Initialization is only defined for internal
11035 -- initialization procedures, where Overridden_Operation
11036 -- is irrelevant. Therefore the setting of this attribute
11037 -- must check whether the target is an init_proc.
11039 elsif not Is_Init_Proc (S) then
11040 Set_Overridden_Operation (S, E);
11041 Inherit_Subprogram_Contract (S, E);
11044 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11046 -- The Ghost policy in effect at the point of declaration
11047 -- of a parent subprogram and an overriding subprogram
11048 -- must match (SPARK RM 6.9(17)).
11050 Check_Ghost_Overriding (S, E);
11052 -- If S is a user-defined subprogram or a null procedure
11053 -- expanded to override an inherited null procedure, or a
11054 -- predefined dispatching primitive then indicate that E
11055 -- overrides the operation from which S is inherited.
11057 if Comes_From_Source (S)
11059 (Present (Parent (S))
11061 Nkind (Parent (S)) = N_Procedure_Specification
11063 Null_Present (Parent (S)))
11065 (Present (Alias (E))
11067 Is_Predefined_Dispatching_Operation (Alias (E)))
11069 if Present (Alias (E)) then
11070 Set_Overridden_Operation (S, Alias (E));
11071 Inherit_Subprogram_Contract (S, Alias (E));
11075 if Is_Dispatching_Operation (E) then
11077 -- An overriding dispatching subprogram inherits the
11078 -- convention of the overridden subprogram (AI-117).
11080 Set_Convention (S, Convention (E));
11081 Check_Dispatching_Operation (S, E);
11084 Check_Dispatching_Operation (S, Empty);
11087 Check_For_Primitive_Subprogram
11088 (Is_Primitive_Subp, Is_Overriding => True);
11089 goto Check_Inequality;
11092 -- Apparent redeclarations in instances can occur when two
11093 -- formal types get the same actual type. The subprograms in
11094 -- in the instance are legal, even if not callable from the
11095 -- outside. Calls from within are disambiguated elsewhere.
11096 -- For dispatching operations in the visible part, the usual
11097 -- rules apply, and operations with the same profile are not
11098 -- legal (B830001).
11100 elsif (In_Instance_Visible_Part
11101 and then not Is_Dispatching_Operation (E))
11102 or else In_Instance_Not_Visible
11106 -- Here we have a real error (identical profile)
11109 Error_Msg_Sloc := Sloc (E);
11111 -- Avoid cascaded errors if the entity appears in
11112 -- subsequent calls.
11114 Set_Scope (S, Current_Scope);
11116 -- Generate error, with extra useful warning for the case
11117 -- of a generic instance with no completion.
11119 if Is_Generic_Instance (S)
11120 and then not Has_Completion (E)
11123 ("instantiation cannot provide body for&", S);
11124 Error_Msg_N ("\& conflicts with declaration#", S);
11126 Error_Msg_N ("& conflicts with declaration#", S);
11133 -- If one subprogram has an access parameter and the other
11134 -- a parameter of an access type, calls to either might be
11135 -- ambiguous. Verify that parameters match except for the
11136 -- access parameter.
11138 if May_Hide_Profile then
11144 F1 := First_Formal (S);
11145 F2 := First_Formal (E);
11146 while Present (F1) and then Present (F2) loop
11147 if Is_Access_Type (Etype (F1)) then
11148 if not Is_Access_Type (Etype (F2))
11149 or else not Conforming_Types
11150 (Designated_Type (Etype (F1)),
11151 Designated_Type (Etype (F2)),
11154 May_Hide_Profile := False;
11158 not Conforming_Types
11159 (Etype (F1), Etype (F2), Type_Conformant)
11161 May_Hide_Profile := False;
11168 if May_Hide_Profile
11172 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11181 -- On exit, we know that S is a new entity
11183 Enter_Overloaded_Entity (S);
11184 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11185 Check_Overriding_Indicator
11186 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11188 -- The Ghost policy in effect at the point of declaration of a parent
11189 -- subprogram and an overriding subprogram must match
11190 -- (SPARK RM 6.9(17)).
11192 Check_Ghost_Overriding (S, Overridden_Subp);
11194 -- Overloading is not allowed in SPARK, except for operators
11196 if Nkind (S) /= N_Defining_Operator_Symbol then
11197 Error_Msg_Sloc := Sloc (Homonym (S));
11198 Check_SPARK_05_Restriction
11199 ("overloading not allowed with entity#", S);
11202 -- If S is a derived operation for an untagged type then by
11203 -- definition it's not a dispatching operation (even if the parent
11204 -- operation was dispatching), so Check_Dispatching_Operation is not
11205 -- called in that case.
11207 if No (Derived_Type)
11208 or else Is_Tagged_Type (Derived_Type)
11210 Check_Dispatching_Operation (S, Empty);
11214 -- If this is a user-defined equality operator that is not a derived
11215 -- subprogram, create the corresponding inequality. If the operation is
11216 -- dispatching, the expansion is done elsewhere, and we do not create
11217 -- an explicit inequality operation.
11219 <<Check_Inequality>>
11220 if Chars (S) = Name_Op_Eq
11221 and then Etype (S) = Standard_Boolean
11222 and then Present (Parent (S))
11223 and then not Is_Dispatching_Operation (S)
11225 Make_Inequality_Operator (S);
11226 Check_Untagged_Equality (S);
11228 end New_Overloaded_Entity;
11230 ---------------------
11231 -- Process_Formals --
11232 ---------------------
11234 procedure Process_Formals
11236 Related_Nod : Node_Id)
11238 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11239 -- Determine whether an access type designates a type coming from a
11242 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11243 -- Check whether the default has a class-wide type. After analysis the
11244 -- default has the type of the formal, so we must also check explicitly
11245 -- for an access attribute.
11247 ----------------------------------
11248 -- Designates_From_Limited_With --
11249 ----------------------------------
11251 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11252 Desig : Entity_Id := Typ;
11255 if Is_Access_Type (Desig) then
11256 Desig := Directly_Designated_Type (Desig);
11259 if Is_Class_Wide_Type (Desig) then
11260 Desig := Root_Type (Desig);
11264 Ekind (Desig) = E_Incomplete_Type
11265 and then From_Limited_With (Desig);
11266 end Designates_From_Limited_With;
11268 ---------------------------
11269 -- Is_Class_Wide_Default --
11270 ---------------------------
11272 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11274 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11275 or else (Nkind (D) = N_Attribute_Reference
11276 and then Attribute_Name (D) = Name_Access
11277 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11278 end Is_Class_Wide_Default;
11282 Context : constant Node_Id := Parent (Parent (T));
11284 Formal : Entity_Id;
11285 Formal_Type : Entity_Id;
11286 Param_Spec : Node_Id;
11289 Num_Out_Params : Nat := 0;
11290 First_Out_Param : Entity_Id := Empty;
11291 -- Used for setting Is_Only_Out_Parameter
11293 -- Start of processing for Process_Formals
11296 -- In order to prevent premature use of the formals in the same formal
11297 -- part, the Ekind is left undefined until all default expressions are
11298 -- analyzed. The Ekind is established in a separate loop at the end.
11300 Param_Spec := First (T);
11301 while Present (Param_Spec) loop
11302 Formal := Defining_Identifier (Param_Spec);
11303 Set_Never_Set_In_Source (Formal, True);
11304 Enter_Name (Formal);
11306 -- Case of ordinary parameters
11308 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11309 Find_Type (Parameter_Type (Param_Spec));
11310 Ptype := Parameter_Type (Param_Spec);
11312 if Ptype = Error then
11316 Formal_Type := Entity (Ptype);
11318 if Is_Incomplete_Type (Formal_Type)
11320 (Is_Class_Wide_Type (Formal_Type)
11321 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11323 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11324 -- primitive operations, as long as their completion is
11325 -- in the same declarative part. If in the private part
11326 -- this means that the type cannot be a Taft-amendment type.
11327 -- Check is done on package exit. For access to subprograms,
11328 -- the use is legal for Taft-amendment types.
11330 -- Ada 2012: tagged incomplete types are allowed as generic
11331 -- formal types. They do not introduce dependencies and the
11332 -- corresponding generic subprogram does not have a delayed
11333 -- freeze, because it does not need a freeze node. However,
11334 -- it is still the case that untagged incomplete types cannot
11335 -- be Taft-amendment types and must be completed in private
11336 -- part, so the subprogram must appear in the list of private
11337 -- dependents of the type.
11339 if Is_Tagged_Type (Formal_Type)
11340 or else (Ada_Version >= Ada_2012
11341 and then not From_Limited_With (Formal_Type)
11342 and then not Is_Generic_Type (Formal_Type))
11344 if Ekind (Scope (Current_Scope)) = E_Package
11345 and then not Is_Generic_Type (Formal_Type)
11346 and then not Is_Class_Wide_Type (Formal_Type)
11349 (Parent (T), N_Access_Function_Definition,
11350 N_Access_Procedure_Definition)
11352 Append_Elmt (Current_Scope,
11353 Private_Dependents (Base_Type (Formal_Type)));
11355 -- Freezing is delayed to ensure that Register_Prim
11356 -- will get called for this operation, which is needed
11357 -- in cases where static dispatch tables aren't built.
11358 -- (Note that the same is done for controlling access
11359 -- parameter cases in function Access_Definition.)
11361 if not Is_Thunk (Current_Scope) then
11362 Set_Has_Delayed_Freeze (Current_Scope);
11367 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11368 N_Access_Procedure_Definition)
11370 -- AI05-0151: Tagged incomplete types are allowed in all
11371 -- formal parts. Untagged incomplete types are not allowed
11372 -- in bodies. Limited views of either kind are not allowed
11373 -- if there is no place at which the non-limited view can
11374 -- become available.
11376 -- Incomplete formal untagged types are not allowed in
11377 -- subprogram bodies (but are legal in their declarations).
11378 -- This excludes bodies created for null procedures, which
11379 -- are basic declarations.
11381 if Is_Generic_Type (Formal_Type)
11382 and then not Is_Tagged_Type (Formal_Type)
11383 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11386 ("invalid use of formal incomplete type", Param_Spec);
11388 elsif Ada_Version >= Ada_2012 then
11389 if Is_Tagged_Type (Formal_Type)
11390 and then (not From_Limited_With (Formal_Type)
11391 or else not In_Package_Body)
11395 elsif Nkind_In (Context, N_Accept_Statement,
11396 N_Accept_Alternative,
11398 or else (Nkind (Context) = N_Subprogram_Body
11399 and then Comes_From_Source (Context))
11402 ("invalid use of untagged incomplete type &",
11403 Ptype, Formal_Type);
11408 ("invalid use of incomplete type&",
11409 Param_Spec, Formal_Type);
11411 -- Further checks on the legality of incomplete types
11412 -- in formal parts are delayed until the freeze point
11413 -- of the enclosing subprogram or access to subprogram.
11417 elsif Ekind (Formal_Type) = E_Void then
11419 ("premature use of&",
11420 Parameter_Type (Param_Spec), Formal_Type);
11423 -- Ada 2012 (AI-142): Handle aliased parameters
11425 if Ada_Version >= Ada_2012
11426 and then Aliased_Present (Param_Spec)
11428 Set_Is_Aliased (Formal);
11431 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11432 -- declaration corresponding to the null-excluding type of the
11433 -- formal in the enclosing scope. Finally, replace the parameter
11434 -- type of the formal with the internal subtype.
11436 if Ada_Version >= Ada_2005
11437 and then Null_Exclusion_Present (Param_Spec)
11439 if not Is_Access_Type (Formal_Type) then
11441 ("`NOT NULL` allowed only for an access type", Param_Spec);
11444 if Can_Never_Be_Null (Formal_Type)
11445 and then Comes_From_Source (Related_Nod)
11448 ("`NOT NULL` not allowed (& already excludes null)",
11449 Param_Spec, Formal_Type);
11453 Create_Null_Excluding_Itype
11455 Related_Nod => Related_Nod,
11456 Scope_Id => Scope (Current_Scope));
11458 -- If the designated type of the itype is an itype that is
11459 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11460 -- on the access subtype, to prevent order-of-elaboration
11461 -- issues in the backend.
11464 -- type T is access procedure;
11465 -- procedure Op (O : not null T);
11467 if Is_Itype (Directly_Designated_Type (Formal_Type))
11469 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11471 Set_Has_Delayed_Freeze (Formal_Type);
11476 -- An access formal type
11480 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11482 -- No need to continue if we already notified errors
11484 if not Present (Formal_Type) then
11488 -- Ada 2005 (AI-254)
11491 AD : constant Node_Id :=
11492 Access_To_Subprogram_Definition
11493 (Parameter_Type (Param_Spec));
11495 if Present (AD) and then Protected_Present (AD) then
11497 Replace_Anonymous_Access_To_Protected_Subprogram
11503 Set_Etype (Formal, Formal_Type);
11505 -- Deal with default expression if present
11507 Default := Expression (Param_Spec);
11509 if Present (Default) then
11510 Check_SPARK_05_Restriction
11511 ("default expression is not allowed", Default);
11513 if Out_Present (Param_Spec) then
11515 ("default initialization only allowed for IN parameters",
11519 -- Do the special preanalysis of the expression (see section on
11520 -- "Handling of Default Expressions" in the spec of package Sem).
11522 Preanalyze_Spec_Expression (Default, Formal_Type);
11524 -- An access to constant cannot be the default for
11525 -- an access parameter that is an access to variable.
11527 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11528 and then not Is_Access_Constant (Formal_Type)
11529 and then Is_Access_Type (Etype (Default))
11530 and then Is_Access_Constant (Etype (Default))
11533 ("formal that is access to variable cannot be initialized "
11534 & "with an access-to-constant expression", Default);
11537 -- Check that the designated type of an access parameter's default
11538 -- is not a class-wide type unless the parameter's designated type
11539 -- is also class-wide.
11541 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11542 and then not Designates_From_Limited_With (Formal_Type)
11543 and then Is_Class_Wide_Default (Default)
11544 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11547 ("access to class-wide expression not allowed here", Default);
11550 -- Check incorrect use of dynamically tagged expressions
11552 if Is_Tagged_Type (Formal_Type) then
11553 Check_Dynamically_Tagged_Expression
11555 Typ => Formal_Type,
11556 Related_Nod => Default);
11560 -- Ada 2005 (AI-231): Static checks
11562 if Ada_Version >= Ada_2005
11563 and then Is_Access_Type (Etype (Formal))
11564 and then Can_Never_Be_Null (Etype (Formal))
11566 Null_Exclusion_Static_Checks (Param_Spec);
11569 -- The following checks are relevant only when SPARK_Mode is on as
11570 -- these are not standard Ada legality rules.
11572 if SPARK_Mode = On then
11573 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11575 -- A function cannot have a parameter of mode IN OUT or OUT
11578 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11580 ("function cannot have parameter of mode `OUT` or "
11581 & "`IN OUT`", Formal);
11584 -- A procedure cannot have an effectively volatile formal
11585 -- parameter of mode IN because it behaves as a constant
11586 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11588 elsif Ekind (Scope (Formal)) = E_Procedure
11589 and then Ekind (Formal) = E_In_Parameter
11590 and then Is_Effectively_Volatile (Formal)
11593 ("formal parameter of mode `IN` cannot be volatile", Formal);
11601 -- If this is the formal part of a function specification, analyze the
11602 -- subtype mark in the context where the formals are visible but not
11603 -- yet usable, and may hide outer homographs.
11605 if Nkind (Related_Nod) = N_Function_Specification then
11606 Analyze_Return_Type (Related_Nod);
11609 -- Now set the kind (mode) of each formal
11611 Param_Spec := First (T);
11612 while Present (Param_Spec) loop
11613 Formal := Defining_Identifier (Param_Spec);
11614 Set_Formal_Mode (Formal);
11616 if Ekind (Formal) = E_In_Parameter then
11617 Set_Default_Value (Formal, Expression (Param_Spec));
11619 if Present (Expression (Param_Spec)) then
11620 Default := Expression (Param_Spec);
11622 if Is_Scalar_Type (Etype (Default)) then
11623 if Nkind (Parameter_Type (Param_Spec)) /=
11624 N_Access_Definition
11626 Formal_Type := Entity (Parameter_Type (Param_Spec));
11630 (Related_Nod, Parameter_Type (Param_Spec));
11633 Apply_Scalar_Range_Check (Default, Formal_Type);
11637 elsif Ekind (Formal) = E_Out_Parameter then
11638 Num_Out_Params := Num_Out_Params + 1;
11640 if Num_Out_Params = 1 then
11641 First_Out_Param := Formal;
11644 elsif Ekind (Formal) = E_In_Out_Parameter then
11645 Num_Out_Params := Num_Out_Params + 1;
11648 -- Skip remaining processing if formal type was in error
11650 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11651 goto Next_Parameter;
11654 -- Force call by reference if aliased
11657 Conv : constant Convention_Id := Convention (Etype (Formal));
11659 if Is_Aliased (Formal) then
11660 Set_Mechanism (Formal, By_Reference);
11662 -- Warn if user asked this to be passed by copy
11664 if Conv = Convention_Ada_Pass_By_Copy then
11666 ("cannot pass aliased parameter & by copy??", Formal);
11669 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11671 elsif Conv = Convention_Ada_Pass_By_Copy then
11672 Set_Mechanism (Formal, By_Copy);
11674 elsif Conv = Convention_Ada_Pass_By_Reference then
11675 Set_Mechanism (Formal, By_Reference);
11683 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11684 Set_Is_Only_Out_Parameter (First_Out_Param);
11686 end Process_Formals;
11688 ----------------------------
11689 -- Reference_Body_Formals --
11690 ----------------------------
11692 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11697 if Error_Posted (Spec) then
11701 -- Iterate over both lists. They may be of different lengths if the two
11702 -- specs are not conformant.
11704 Fs := First_Formal (Spec);
11705 Fb := First_Formal (Bod);
11706 while Present (Fs) and then Present (Fb) loop
11707 Generate_Reference (Fs, Fb, 'b');
11709 if Style_Check then
11710 Style.Check_Identifier (Fb, Fs);
11713 Set_Spec_Entity (Fb, Fs);
11714 Set_Referenced (Fs, False);
11718 end Reference_Body_Formals;
11720 -------------------------
11721 -- Set_Actual_Subtypes --
11722 -------------------------
11724 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11726 Formal : Entity_Id;
11728 First_Stmt : Node_Id := Empty;
11729 AS_Needed : Boolean;
11732 -- If this is an empty initialization procedure, no need to create
11733 -- actual subtypes (small optimization).
11735 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11738 -- Within a predicate function we do not want to generate local
11739 -- subtypes that may generate nested predicate functions.
11741 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11745 -- The subtype declarations may freeze the formals. The body generated
11746 -- for an expression function is not a freeze point, so do not emit
11747 -- these declarations (small loss of efficiency in rare cases).
11749 if Nkind (N) = N_Subprogram_Body
11750 and then Was_Expression_Function (N)
11755 Formal := First_Formal (Subp);
11756 while Present (Formal) loop
11757 T := Etype (Formal);
11759 -- We never need an actual subtype for a constrained formal
11761 if Is_Constrained (T) then
11762 AS_Needed := False;
11764 -- If we have unknown discriminants, then we do not need an actual
11765 -- subtype, or more accurately we cannot figure it out. Note that
11766 -- all class-wide types have unknown discriminants.
11768 elsif Has_Unknown_Discriminants (T) then
11769 AS_Needed := False;
11771 -- At this stage we have an unconstrained type that may need an
11772 -- actual subtype. For sure the actual subtype is needed if we have
11773 -- an unconstrained array type. However, in an instance, the type
11774 -- may appear as a subtype of the full view, while the actual is
11775 -- in fact private (in which case no actual subtype is needed) so
11776 -- check the kind of the base type.
11778 elsif Is_Array_Type (Base_Type (T)) then
11781 -- The only other case needing an actual subtype is an unconstrained
11782 -- record type which is an IN parameter (we cannot generate actual
11783 -- subtypes for the OUT or IN OUT case, since an assignment can
11784 -- change the discriminant values. However we exclude the case of
11785 -- initialization procedures, since discriminants are handled very
11786 -- specially in this context, see the section entitled "Handling of
11787 -- Discriminants" in Einfo.
11789 -- We also exclude the case of Discrim_SO_Functions (functions used
11790 -- in front-end layout mode for size/offset values), since in such
11791 -- functions only discriminants are referenced, and not only are such
11792 -- subtypes not needed, but they cannot always be generated, because
11793 -- of order of elaboration issues.
11795 elsif Is_Record_Type (T)
11796 and then Ekind (Formal) = E_In_Parameter
11797 and then Chars (Formal) /= Name_uInit
11798 and then not Is_Unchecked_Union (T)
11799 and then not Is_Discrim_SO_Function (Subp)
11803 -- All other cases do not need an actual subtype
11806 AS_Needed := False;
11809 -- Generate actual subtypes for unconstrained arrays and
11810 -- unconstrained discriminated records.
11813 if Nkind (N) = N_Accept_Statement then
11815 -- If expansion is active, the formal is replaced by a local
11816 -- variable that renames the corresponding entry of the
11817 -- parameter block, and it is this local variable that may
11818 -- require an actual subtype.
11820 if Expander_Active then
11821 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11823 Decl := Build_Actual_Subtype (T, Formal);
11826 if Present (Handled_Statement_Sequence (N)) then
11828 First (Statements (Handled_Statement_Sequence (N)));
11829 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11830 Mark_Rewrite_Insertion (Decl);
11832 -- If the accept statement has no body, there will be no
11833 -- reference to the actuals, so no need to compute actual
11840 Decl := Build_Actual_Subtype (T, Formal);
11841 Prepend (Decl, Declarations (N));
11842 Mark_Rewrite_Insertion (Decl);
11845 -- The declaration uses the bounds of an existing object, and
11846 -- therefore needs no constraint checks.
11848 Analyze (Decl, Suppress => All_Checks);
11849 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11851 -- We need to freeze manually the generated type when it is
11852 -- inserted anywhere else than in a declarative part.
11854 if Present (First_Stmt) then
11855 Insert_List_Before_And_Analyze (First_Stmt,
11856 Freeze_Entity (Defining_Identifier (Decl), N));
11858 -- Ditto if the type has a dynamic predicate, because the
11859 -- generated function will mention the actual subtype. The
11860 -- predicate may come from an explicit aspect of be inherited.
11862 elsif Has_Predicates (T) then
11863 Insert_List_Before_And_Analyze (Decl,
11864 Freeze_Entity (Defining_Identifier (Decl), N));
11867 if Nkind (N) = N_Accept_Statement
11868 and then Expander_Active
11870 Set_Actual_Subtype (Renamed_Object (Formal),
11871 Defining_Identifier (Decl));
11873 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11877 Next_Formal (Formal);
11879 end Set_Actual_Subtypes;
11881 ---------------------
11882 -- Set_Formal_Mode --
11883 ---------------------
11885 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11886 Spec : constant Node_Id := Parent (Formal_Id);
11887 Id : constant Entity_Id := Scope (Formal_Id);
11890 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11891 -- since we ensure that corresponding actuals are always valid at the
11892 -- point of the call.
11894 if Out_Present (Spec) then
11895 if Ekind_In (Id, E_Entry, E_Entry_Family)
11896 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11898 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11901 if Ekind_In (Id, E_Function, E_Generic_Function) then
11903 -- [IN] OUT parameters allowed for functions in Ada 2012
11905 if Ada_Version >= Ada_2012 then
11907 -- Even in Ada 2012 operators can only have IN parameters
11909 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11910 Error_Msg_N ("operators can only have IN parameters", Spec);
11913 if In_Present (Spec) then
11914 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11916 Set_Ekind (Formal_Id, E_Out_Parameter);
11919 -- But not in earlier versions of Ada
11922 Error_Msg_N ("functions can only have IN parameters", Spec);
11923 Set_Ekind (Formal_Id, E_In_Parameter);
11926 elsif In_Present (Spec) then
11927 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11930 Set_Ekind (Formal_Id, E_Out_Parameter);
11931 Set_Never_Set_In_Source (Formal_Id, True);
11932 Set_Is_True_Constant (Formal_Id, False);
11933 Set_Current_Value (Formal_Id, Empty);
11937 Set_Ekind (Formal_Id, E_In_Parameter);
11940 -- Set Is_Known_Non_Null for access parameters since the language
11941 -- guarantees that access parameters are always non-null. We also set
11942 -- Can_Never_Be_Null, since there is no way to change the value.
11944 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11946 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11947 -- null; In Ada 2005, only if then null_exclusion is explicit.
11949 if Ada_Version < Ada_2005
11950 or else Can_Never_Be_Null (Etype (Formal_Id))
11952 Set_Is_Known_Non_Null (Formal_Id);
11953 Set_Can_Never_Be_Null (Formal_Id);
11956 -- Ada 2005 (AI-231): Null-exclusion access subtype
11958 elsif Is_Access_Type (Etype (Formal_Id))
11959 and then Can_Never_Be_Null (Etype (Formal_Id))
11961 Set_Is_Known_Non_Null (Formal_Id);
11963 -- We can also set Can_Never_Be_Null (thus preventing some junk
11964 -- access checks) for the case of an IN parameter, which cannot
11965 -- be changed, or for an IN OUT parameter, which can be changed but
11966 -- not to a null value. But for an OUT parameter, the initial value
11967 -- passed in can be null, so we can't set this flag in that case.
11969 if Ekind (Formal_Id) /= E_Out_Parameter then
11970 Set_Can_Never_Be_Null (Formal_Id);
11974 Set_Mechanism (Formal_Id, Default_Mechanism);
11975 Set_Formal_Validity (Formal_Id);
11976 end Set_Formal_Mode;
11978 -------------------------
11979 -- Set_Formal_Validity --
11980 -------------------------
11982 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11984 -- If no validity checking, then we cannot assume anything about the
11985 -- validity of parameters, since we do not know there is any checking
11986 -- of the validity on the call side.
11988 if not Validity_Checks_On then
11991 -- If validity checking for parameters is enabled, this means we are
11992 -- not supposed to make any assumptions about argument values.
11994 elsif Validity_Check_Parameters then
11997 -- If we are checking in parameters, we will assume that the caller is
11998 -- also checking parameters, so we can assume the parameter is valid.
12000 elsif Ekind (Formal_Id) = E_In_Parameter
12001 and then Validity_Check_In_Params
12003 Set_Is_Known_Valid (Formal_Id, True);
12005 -- Similar treatment for IN OUT parameters
12007 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12008 and then Validity_Check_In_Out_Params
12010 Set_Is_Known_Valid (Formal_Id, True);
12012 end Set_Formal_Validity;
12014 ------------------------
12015 -- Subtype_Conformant --
12016 ------------------------
12018 function Subtype_Conformant
12019 (New_Id : Entity_Id;
12020 Old_Id : Entity_Id;
12021 Skip_Controlling_Formals : Boolean := False) return Boolean
12025 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12026 Skip_Controlling_Formals => Skip_Controlling_Formals);
12028 end Subtype_Conformant;
12030 ---------------------
12031 -- Type_Conformant --
12032 ---------------------
12034 function Type_Conformant
12035 (New_Id : Entity_Id;
12036 Old_Id : Entity_Id;
12037 Skip_Controlling_Formals : Boolean := False) return Boolean
12041 May_Hide_Profile := False;
12043 (New_Id, Old_Id, Type_Conformant, False, Result,
12044 Skip_Controlling_Formals => Skip_Controlling_Formals);
12046 end Type_Conformant;
12048 -------------------------------
12049 -- Valid_Operator_Definition --
12050 -------------------------------
12052 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12055 Id : constant Name_Id := Chars (Designator);
12059 F := First_Formal (Designator);
12060 while Present (F) loop
12063 if Present (Default_Value (F)) then
12065 ("default values not allowed for operator parameters",
12068 -- For function instantiations that are operators, we must check
12069 -- separately that the corresponding generic only has in-parameters.
12070 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12071 -- an error could not arise in earlier versions of the language.
12073 elsif Ekind (F) /= E_In_Parameter then
12074 Error_Msg_N ("operators can only have IN parameters", F);
12080 -- Verify that user-defined operators have proper number of arguments
12081 -- First case of operators which can only be unary
12083 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12086 -- Case of operators which can be unary or binary
12088 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12089 N_OK := (N in 1 .. 2);
12091 -- All other operators can only be binary
12099 ("incorrect number of arguments for operator", Designator);
12103 and then Base_Type (Etype (Designator)) = Standard_Boolean
12104 and then not Is_Intrinsic_Subprogram (Designator)
12107 ("explicit definition of inequality not allowed", Designator);
12109 end Valid_Operator_Definition;