1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, 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_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
210 -- Formal_Id is an formal parameter entity. This procedure deals with
211 -- setting the proper validity status for this entity, which depends on
212 -- the kind of parameter and the validity checking mode.
214 ---------------------------------------------
215 -- Analyze_Abstract_Subprogram_Declaration --
216 ---------------------------------------------
218 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
219 Scop : constant Entity_Id := Current_Scope;
220 Subp_Id : constant Entity_Id :=
221 Analyze_Subprogram_Specification (Specification (N));
224 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
226 Generate_Definition (Subp_Id);
228 -- Set the SPARK mode from the current context (may be overwritten later
229 -- with explicit pragma).
231 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
232 Set_SPARK_Pragma_Inherited (Subp_Id);
234 -- Preserve relevant elaboration-related attributes of the context which
235 -- are no longer available or very expensive to recompute once analysis,
236 -- resolution, and expansion are over.
238 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, and itypes whose
370 -- scope is another type (i.e. component subtypes that depend
371 -- on a discriminant),
374 and then (Scope_Within_Or_Same (Scope (Typ), Def_Id)
375 or else Is_Type (Scope (Typ)))
380 -- This provides a better error message than generating
381 -- primitives whose compilation fails much later. Refine
382 -- the error message if possible.
384 Check_Fully_Declared (Typ, Node);
386 if Error_Posted (Node) then
387 if Has_Private_Component (Typ)
388 and then not Is_Private_Type (Typ)
390 Error_Msg_NE ("\type& has private component", Node, Typ);
394 Freeze_Before (N, Typ);
396 end Check_And_Freeze_Type;
398 -- Start of processing for Freeze_Type_Refs
401 -- Check that a type referenced by an entity can be frozen
403 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
404 Check_And_Freeze_Type (Etype (Entity (Node)));
406 -- Check that the enclosing record type can be frozen
408 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
409 Check_And_Freeze_Type (Scope (Entity (Node)));
412 -- Freezing an access type does not freeze the designated type,
413 -- but freezing conversions between access to interfaces requires
414 -- that the interface types themselves be frozen, so that dispatch
415 -- table entities are properly created.
417 -- Unclear whether a more general rule is needed ???
419 elsif Nkind (Node) = N_Type_Conversion
420 and then Is_Access_Type (Etype (Node))
421 and then Is_Interface (Designated_Type (Etype (Node)))
423 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
426 -- An implicit dereference freezes the designated type. In the
427 -- case of a dispatching call whose controlling argument is an
428 -- access type, the dereference is not made explicit, so we must
429 -- check for such a call and freeze the designated type.
431 if Nkind (Node) in N_Has_Etype
432 and then Present (Etype (Node))
433 and then Is_Access_Type (Etype (Node))
434 and then Nkind (Parent (Node)) = N_Function_Call
435 and then Node = Controlling_Argument (Parent (Node))
437 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
440 -- No point in posting several errors on the same expression
442 if Serious_Errors_Detected > 0 then
447 end Freeze_Type_Refs;
449 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs);
453 Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id);
454 Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id);
455 Dup_Expr : constant Node_Id := Cloned_Expression;
457 -- Start of processing for Freeze_Expr_Types
460 -- Preanalyze a duplicate of the expression to have available the
461 -- minimum decoration needed to locate referenced unfrozen types
462 -- without adding any decoration to the function expression.
465 Install_Formals (Def_Id);
467 Preanalyze_Spec_Expression (Dup_Expr, Etype (Def_Id));
470 -- Restore certain attributes of Def_Id since the preanalysis may
471 -- have introduced itypes to this scope, thus modifying attributes
472 -- First_Entity and Last_Entity.
474 Set_First_Entity (Def_Id, Saved_First_Entity);
475 Set_Last_Entity (Def_Id, Saved_Last_Entity);
477 if Present (Last_Entity (Def_Id)) then
478 Set_Next_Entity (Last_Entity (Def_Id), Empty);
481 -- Freeze all types referenced in the expression
483 Freeze_References (Dup_Expr);
484 end Freeze_Expr_Types;
494 Def_Id : Entity_Id := Empty;
496 -- If the expression is a completion, Prev is the entity whose
497 -- declaration is completed. Def_Id is needed to analyze the spec.
499 -- Start of processing for Analyze_Expression_Function
502 -- This is one of the occasions on which we transform the tree during
503 -- semantic analysis. If this is a completion, transform the expression
504 -- function into an equivalent subprogram body, and analyze it.
506 -- Expression functions are inlined unconditionally. The back-end will
507 -- determine whether this is possible.
509 Inline_Processing_Required := True;
511 -- Create a specification for the generated body. This must be done
512 -- prior to the analysis of the initial declaration.
514 New_Spec := Copy_Subprogram_Spec (Spec);
515 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
517 -- If there are previous overloadable entities with the same name,
518 -- check whether any of them is completed by the expression function.
519 -- In a generic context a formal subprogram has no completion.
522 and then Is_Overloadable (Prev)
523 and then not Is_Formal_Subprogram (Prev)
525 Def_Id := Analyze_Subprogram_Specification (Spec);
526 Prev := Find_Corresponding_Spec (N);
528 -- The previous entity may be an expression function as well, in
529 -- which case the redeclaration is illegal.
532 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
533 N_Expression_Function
535 Error_Msg_Sloc := Sloc (Prev);
536 Error_Msg_N ("& conflicts with declaration#", Def_Id);
541 Ret := Make_Simple_Return_Statement (LocX, Expr);
544 Make_Subprogram_Body (Loc,
545 Specification => New_Spec,
546 Declarations => Empty_List,
547 Handled_Statement_Sequence =>
548 Make_Handled_Sequence_Of_Statements (LocX,
549 Statements => New_List (Ret)));
550 Set_Was_Expression_Function (New_Body);
552 -- If the expression completes a generic subprogram, we must create a
553 -- separate node for the body, because at instantiation the original
554 -- node of the generic copy must be a generic subprogram body, and
555 -- cannot be a expression function. Otherwise we just rewrite the
556 -- expression with the non-generic body.
558 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
559 Insert_After (N, New_Body);
561 -- Propagate any aspects or pragmas that apply to the expression
562 -- function to the proper body when the expression function acts
565 if Has_Aspects (N) then
566 Move_Aspects (N, To => New_Body);
569 Relocate_Pragmas_To_Body (New_Body);
571 Rewrite (N, Make_Null_Statement (Loc));
572 Set_Has_Completion (Prev, False);
575 Set_Is_Inlined (Prev);
577 -- If the expression function is a completion, the previous declaration
578 -- must come from source. We know already that it appears in the current
579 -- scope. The entity itself may be internally created if within a body
583 and then Is_Overloadable (Prev)
584 and then not Is_Formal_Subprogram (Prev)
585 and then Comes_From_Source (Parent (Prev))
587 Set_Has_Completion (Prev, False);
588 Set_Is_Inlined (Prev);
590 -- AI12-0103: Expression functions that are a completion freeze their
591 -- expression but don't freeze anything else (unlike regular bodies).
593 -- Note that we cannot defer this freezing to the analysis of the
594 -- expression itself, because a freeze node might appear in a nested
595 -- scope, leading to an elaboration order issue in gigi.
596 -- As elsewhere, we do not emit freeze nodes within a generic unit.
598 if not Inside_A_Generic then
599 Freeze_Expr_Types (Def_Id);
602 -- For navigation purposes, indicate that the function is a body
604 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
605 Rewrite (N, New_Body);
607 -- Remove any existing aspects from the original node because the act
608 -- of rewriting causes the list to be shared between the two nodes.
610 Orig_N := Original_Node (N);
611 Remove_Aspects (Orig_N);
613 -- Propagate any pragmas that apply to expression function to the
614 -- proper body when the expression function acts as a completion.
615 -- Aspects are automatically transfered because of node rewriting.
617 Relocate_Pragmas_To_Body (N);
620 -- Once the aspects of the generated body have been analyzed, create
621 -- a copy for ASIS purposes and associate it with the original node.
623 if Has_Aspects (N) then
624 Set_Aspect_Specifications (Orig_N,
625 New_Copy_List_Tree (Aspect_Specifications (N)));
628 -- Prev is the previous entity with the same name, but it is can
629 -- be an unrelated spec that is not completed by the expression
630 -- function. In that case the relevant entity is the one in the body.
631 -- Not clear that the backend can inline it in this case ???
633 if Has_Completion (Prev) then
635 -- The formals of the expression function are body formals,
636 -- and do not appear in the ali file, which will only contain
637 -- references to the formals of the original subprogram spec.
644 F1 := First_Formal (Def_Id);
645 F2 := First_Formal (Prev);
647 while Present (F1) loop
648 Set_Spec_Entity (F1, F2);
655 Set_Is_Inlined (Defining_Entity (New_Body));
658 -- If this is not a completion, create both a declaration and a body, so
659 -- that the expression can be inlined whenever possible.
662 -- An expression function that is not a completion is not a
663 -- subprogram declaration, and thus cannot appear in a protected
666 if Nkind (Parent (N)) = N_Protected_Definition then
668 ("an expression function is not a legal protected operation", N);
671 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
673 -- Remove any existing aspects from the original node because the act
674 -- of rewriting causes the list to be shared between the two nodes.
676 Orig_N := Original_Node (N);
677 Remove_Aspects (Orig_N);
681 -- Once the aspects of the generated spec have been analyzed, create
682 -- a copy for ASIS purposes and associate it with the original node.
684 if Has_Aspects (N) then
685 Set_Aspect_Specifications (Orig_N,
686 New_Copy_List_Tree (Aspect_Specifications (N)));
689 -- If aspect SPARK_Mode was specified on the body, it needs to be
690 -- repeated both on the generated spec and the body.
692 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
694 if Present (Asp) then
695 Asp := New_Copy_Tree (Asp);
696 Set_Analyzed (Asp, False);
697 Set_Aspect_Specifications (New_Body, New_List (Asp));
700 Def_Id := Defining_Entity (N);
701 Set_Is_Inlined (Def_Id);
703 -- Establish the linkages between the spec and the body. These are
704 -- used when the expression function acts as the prefix of attribute
705 -- 'Access in order to freeze the original expression which has been
706 -- moved to the generated body.
708 Set_Corresponding_Body (N, Defining_Entity (New_Body));
709 Set_Corresponding_Spec (New_Body, Def_Id);
711 -- Within a generic preanalyze the original expression for name
712 -- capture. The body is also generated but plays no role in
713 -- this because it is not part of the original source.
715 if Inside_A_Generic then
716 Set_Has_Completion (Def_Id);
718 Install_Formals (Def_Id);
719 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
723 -- To prevent premature freeze action, insert the new body at the end
724 -- of the current declarations, or at the end of the package spec.
725 -- However, resolve usage names now, to prevent spurious visibility
726 -- on later entities. Note that the function can now be called in
727 -- the current declarative part, which will appear to be prior to
728 -- the presence of the body in the code. There are nevertheless no
729 -- order of elaboration issues because all name resolution has taken
730 -- place at the point of declaration.
733 Decls : List_Id := List_Containing (N);
734 Expr : constant Node_Id := Expression (Ret);
735 Par : constant Node_Id := Parent (Decls);
736 Typ : constant Entity_Id := Etype (Def_Id);
739 -- If this is a wrapper created for in an instance for a formal
740 -- subprogram, insert body after declaration, to be analyzed when
741 -- the enclosing instance is analyzed.
744 and then Is_Generic_Actual_Subprogram (Def_Id)
746 Insert_After (N, New_Body);
749 if Nkind (Par) = N_Package_Specification
750 and then Decls = Visible_Declarations (Par)
751 and then Present (Private_Declarations (Par))
752 and then not Is_Empty_List (Private_Declarations (Par))
754 Decls := Private_Declarations (Par);
757 Insert_After (Last (Decls), New_Body);
759 -- Preanalyze the expression if not already done above
761 if not Inside_A_Generic then
763 Install_Formals (Def_Id);
764 Preanalyze_Spec_Expression (Expr, Typ);
765 Check_Limited_Return (Original_Node (N), Expr, Typ);
772 -- Check incorrect use of dynamically tagged expression. This doesn't
773 -- fall out automatically when analyzing the generated function body,
774 -- because Check_Dynamically_Tagged_Expression deliberately ignores
775 -- nodes that don't come from source.
778 and then Nkind (Def_Id) in N_Has_Etype
779 and then Is_Tagged_Type (Etype (Def_Id))
781 Check_Dynamically_Tagged_Expression
783 Typ => Etype (Def_Id),
784 Related_Nod => Original_Node (N));
787 -- We must enforce checks for unreferenced formals in our newly
788 -- generated function, so we propagate the referenced flag from the
789 -- original spec to the new spec as well as setting Comes_From_Source.
791 if Present (Parameter_Specifications (New_Spec)) then
793 Form_New_Def : Entity_Id;
794 Form_New_Spec : Entity_Id;
795 Form_Old_Def : Entity_Id;
796 Form_Old_Spec : Entity_Id;
799 Form_New_Spec := First (Parameter_Specifications (New_Spec));
800 Form_Old_Spec := First (Parameter_Specifications (Spec));
802 while Present (Form_New_Spec) and then Present (Form_Old_Spec) loop
803 Form_New_Def := Defining_Identifier (Form_New_Spec);
804 Form_Old_Def := Defining_Identifier (Form_Old_Spec);
806 Set_Comes_From_Source (Form_New_Def, True);
808 -- Because of the usefulness of unreferenced controlling
809 -- formals we exempt them from unreferenced warnings by marking
810 -- them as always referenced.
812 Set_Referenced (Form_Old_Def,
813 (Is_Formal (Form_Old_Def)
814 and then Is_Controlling_Formal (Form_Old_Def))
815 or else Referenced (Form_Old_Def));
817 Next (Form_New_Spec);
818 Next (Form_Old_Spec);
822 end Analyze_Expression_Function;
824 ----------------------------------------
825 -- Analyze_Extended_Return_Statement --
826 ----------------------------------------
828 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
830 Check_Compiler_Unit ("extended return statement", N);
831 Analyze_Return_Statement (N);
832 end Analyze_Extended_Return_Statement;
834 ----------------------------
835 -- Analyze_Function_Call --
836 ----------------------------
838 procedure Analyze_Function_Call (N : Node_Id) is
839 Actuals : constant List_Id := Parameter_Associations (N);
840 Func_Nam : constant Node_Id := Name (N);
846 -- A call of the form A.B (X) may be an Ada 2005 call, which is
847 -- rewritten as B (A, X). If the rewriting is successful, the call
848 -- has been analyzed and we just return.
850 if Nkind (Func_Nam) = N_Selected_Component
851 and then Name (N) /= Func_Nam
852 and then Is_Rewrite_Substitution (N)
853 and then Present (Etype (N))
858 -- If error analyzing name, then set Any_Type as result type and return
860 if Etype (Func_Nam) = Any_Type then
861 Set_Etype (N, Any_Type);
865 -- Otherwise analyze the parameters
867 if Present (Actuals) then
868 Actual := First (Actuals);
869 while Present (Actual) loop
871 Check_Parameterless_Call (Actual);
877 end Analyze_Function_Call;
879 -----------------------------
880 -- Analyze_Function_Return --
881 -----------------------------
883 procedure Analyze_Function_Return (N : Node_Id) is
884 Loc : constant Source_Ptr := Sloc (N);
885 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
886 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
888 R_Type : constant Entity_Id := Etype (Scope_Id);
889 -- Function result subtype
891 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
892 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
893 -- aggregate in a return statement.
895 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
896 -- Check that the return_subtype_indication properly matches the result
897 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
899 -----------------------------------
900 -- Check_Aggregate_Accessibility --
901 -----------------------------------
903 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
904 Typ : constant Entity_Id := Etype (Aggr);
911 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
912 Discr := First_Discriminant (Typ);
913 Assoc := First (Component_Associations (Aggr));
914 while Present (Discr) loop
915 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
916 Expr := Expression (Assoc);
918 if Nkind (Expr) = N_Attribute_Reference
919 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
921 Obj := Prefix (Expr);
922 while Nkind_In (Obj, N_Indexed_Component,
923 N_Selected_Component)
928 -- Do not check aliased formals or function calls. A
929 -- run-time check may still be needed ???
931 if Is_Entity_Name (Obj)
932 and then Comes_From_Source (Obj)
934 if Is_Formal (Entity (Obj))
935 and then Is_Aliased (Entity (Obj))
939 elsif Object_Access_Level (Obj) >
940 Scope_Depth (Scope (Scope_Id))
943 ("access discriminant in return aggregate would "
944 & "be a dangling reference", Obj);
950 Next_Discriminant (Discr);
953 end Check_Aggregate_Accessibility;
955 -------------------------------------
956 -- Check_Return_Subtype_Indication --
957 -------------------------------------
959 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
960 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
962 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
963 -- Subtype given in the extended return statement (must match R_Type)
965 Subtype_Ind : constant Node_Id :=
966 Object_Definition (Original_Node (Obj_Decl));
968 procedure Error_No_Match (N : Node_Id);
969 -- Output error messages for case where types do not statically
970 -- match. N is the location for the messages.
976 procedure Error_No_Match (N : Node_Id) is
979 ("subtype must statically match function result subtype", N);
981 if not Predicates_Match (R_Stm_Type, R_Type) then
982 Error_Msg_Node_2 := R_Type;
984 ("\predicate of& does not match predicate of&",
989 -- Start of processing for Check_Return_Subtype_Indication
992 -- First, avoid cascaded errors
994 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
998 -- "return access T" case; check that the return statement also has
999 -- "access T", and that the subtypes statically match:
1000 -- if this is an access to subprogram the signatures must match.
1002 if Is_Anonymous_Access_Type (R_Type) then
1003 if Is_Anonymous_Access_Type (R_Stm_Type) then
1004 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
1006 if Base_Type (Designated_Type (R_Stm_Type)) /=
1007 Base_Type (Designated_Type (R_Type))
1008 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
1010 Error_No_Match (Subtype_Mark (Subtype_Ind));
1014 -- For two anonymous access to subprogram types, the types
1015 -- themselves must be type conformant.
1017 if not Conforming_Types
1018 (R_Stm_Type, R_Type, Fully_Conformant)
1020 Error_No_Match (Subtype_Ind);
1025 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
1028 -- If the return object is of an anonymous access type, then report
1029 -- an error if the function's result type is not also anonymous.
1031 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
1032 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
1034 ("anonymous access not allowed for function with named access "
1035 & "result", Subtype_Ind);
1037 -- Subtype indication case: check that the return object's type is
1038 -- covered by the result type, and that the subtypes statically match
1039 -- when the result subtype is constrained. Also handle record types
1040 -- with unknown discriminants for which we have built the underlying
1041 -- record view. Coverage is needed to allow specific-type return
1042 -- objects when the result type is class-wide (see AI05-32).
1044 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
1045 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1048 (Base_Type (R_Type),
1049 Underlying_Record_View (Base_Type (R_Stm_Type))))
1051 -- A null exclusion may be present on the return type, on the
1052 -- function specification, on the object declaration or on the
1055 if Is_Access_Type (R_Type)
1057 (Can_Never_Be_Null (R_Type)
1058 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1059 Can_Never_Be_Null (R_Stm_Type)
1061 Error_No_Match (Subtype_Ind);
1064 -- AI05-103: for elementary types, subtypes must statically match
1066 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1067 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1068 Error_No_Match (Subtype_Ind);
1072 -- All remaining cases are illegal
1074 -- Note: previous versions of this subprogram allowed the return
1075 -- value to be the ancestor of the return type if the return type
1076 -- was a null extension. This was plainly incorrect.
1080 ("wrong type for return_subtype_indication", Subtype_Ind);
1082 end Check_Return_Subtype_Indication;
1084 ---------------------
1085 -- Local Variables --
1086 ---------------------
1089 Obj_Decl : Node_Id := Empty;
1091 -- Start of processing for Analyze_Function_Return
1094 Set_Return_Present (Scope_Id);
1096 if Nkind (N) = N_Simple_Return_Statement then
1097 Expr := Expression (N);
1099 -- Guard against a malformed expression. The parser may have tried to
1100 -- recover but the node is not analyzable.
1102 if Nkind (Expr) = N_Error then
1103 Set_Etype (Expr, Any_Type);
1104 Expander_Mode_Save_And_Set (False);
1108 -- The resolution of a controlled [extension] aggregate associated
1109 -- with a return statement creates a temporary which needs to be
1110 -- finalized on function exit. Wrap the return statement inside a
1111 -- block so that the finalization machinery can detect this case.
1112 -- This early expansion is done only when the return statement is
1113 -- not part of a handled sequence of statements.
1115 if Nkind_In (Expr, N_Aggregate,
1116 N_Extension_Aggregate)
1117 and then Needs_Finalization (R_Type)
1118 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1121 Make_Block_Statement (Loc,
1122 Handled_Statement_Sequence =>
1123 Make_Handled_Sequence_Of_Statements (Loc,
1124 Statements => New_List (Relocate_Node (N)))));
1132 -- Ada 2005 (AI-251): If the type of the returned object is
1133 -- an access to an interface type then we add an implicit type
1134 -- conversion to force the displacement of the "this" pointer to
1135 -- reference the secondary dispatch table. We cannot delay the
1136 -- generation of this implicit conversion until the expansion
1137 -- because in this case the type resolution changes the decoration
1138 -- of the expression node to match R_Type; by contrast, if the
1139 -- returned object is a class-wide interface type then it is too
1140 -- early to generate here the implicit conversion since the return
1141 -- statement may be rewritten by the expander into an extended
1142 -- return statement whose expansion takes care of adding the
1143 -- implicit type conversion to displace the pointer to the object.
1146 and then Serious_Errors_Detected = 0
1147 and then Is_Access_Type (R_Type)
1148 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1149 and then Is_Interface (Designated_Type (R_Type))
1150 and then Is_Progenitor (Designated_Type (R_Type),
1151 Designated_Type (Etype (Expr)))
1153 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1157 Resolve (Expr, R_Type);
1158 Check_Limited_Return (N, Expr, R_Type);
1160 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
1161 Check_Aggregate_Accessibility (Expr);
1165 -- RETURN only allowed in SPARK as the last statement in function
1167 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1169 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1170 or else Present (Next (N)))
1172 Check_SPARK_05_Restriction
1173 ("RETURN should be the last statement in function", N);
1177 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1178 Obj_Decl := Last (Return_Object_Declarations (N));
1180 -- Analyze parts specific to extended_return_statement:
1183 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1184 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1187 Expr := Expression (Obj_Decl);
1189 -- Note: The check for OK_For_Limited_Init will happen in
1190 -- Analyze_Object_Declaration; we treat it as a normal
1191 -- object declaration.
1193 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1196 Check_Return_Subtype_Indication (Obj_Decl);
1198 if Present (HSS) then
1201 if Present (Exception_Handlers (HSS)) then
1203 -- ???Has_Nested_Block_With_Handler needs to be set.
1204 -- Probably by creating an actual N_Block_Statement.
1205 -- Probably in Expand.
1211 -- Mark the return object as referenced, since the return is an
1212 -- implicit reference of the object.
1214 Set_Referenced (Defining_Identifier (Obj_Decl));
1216 Check_References (Stm_Entity);
1218 -- Check RM 6.5 (5.9/3)
1221 if Ada_Version < Ada_2012 then
1223 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1224 -- Can it really happen (extended return???)
1227 ("aliased only allowed for limited return objects "
1228 & "in Ada 2012??", N);
1230 elsif not Is_Limited_View (R_Type) then
1232 ("aliased only allowed for limited return objects", N);
1238 -- Case of Expr present
1240 if Present (Expr) then
1242 -- Defend against previous errors
1244 if Nkind (Expr) = N_Empty
1245 or else No (Etype (Expr))
1250 -- Apply constraint check. Note that this is done before the implicit
1251 -- conversion of the expression done for anonymous access types to
1252 -- ensure correct generation of the null-excluding check associated
1253 -- with null-excluding expressions found in return statements.
1255 Apply_Constraint_Check (Expr, R_Type);
1257 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1258 -- type, apply an implicit conversion of the expression to that type
1259 -- to force appropriate static and run-time accessibility checks.
1261 if Ada_Version >= Ada_2005
1262 and then Ekind (R_Type) = E_Anonymous_Access_Type
1264 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1265 Analyze_And_Resolve (Expr, R_Type);
1267 -- If this is a local anonymous access to subprogram, the
1268 -- accessibility check can be applied statically. The return is
1269 -- illegal if the access type of the return expression is declared
1270 -- inside of the subprogram (except if it is the subtype indication
1271 -- of an extended return statement).
1273 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1274 if not Comes_From_Source (Current_Scope)
1275 or else Ekind (Current_Scope) = E_Return_Statement
1280 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1282 Error_Msg_N ("cannot return local access to subprogram", N);
1285 -- The expression cannot be of a formal incomplete type
1287 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1288 and then Is_Generic_Type (Etype (Expr))
1291 ("cannot return expression of a formal incomplete type", N);
1294 -- If the result type is class-wide, then check that the return
1295 -- expression's type is not declared at a deeper level than the
1296 -- function (RM05-6.5(5.6/2)).
1298 if Ada_Version >= Ada_2005
1299 and then Is_Class_Wide_Type (R_Type)
1301 if Type_Access_Level (Etype (Expr)) >
1302 Subprogram_Access_Level (Scope_Id)
1305 ("level of return expression type is deeper than "
1306 & "class-wide function!", Expr);
1310 -- Check incorrect use of dynamically tagged expression
1312 if Is_Tagged_Type (R_Type) then
1313 Check_Dynamically_Tagged_Expression
1319 -- ??? A real run-time accessibility check is needed in cases
1320 -- involving dereferences of access parameters. For now we just
1321 -- check the static cases.
1323 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1324 and then Is_Limited_View (Etype (Scope_Id))
1325 and then Object_Access_Level (Expr) >
1326 Subprogram_Access_Level (Scope_Id)
1328 -- Suppress the message in a generic, where the rewriting
1331 if Inside_A_Generic then
1336 Make_Raise_Program_Error (Loc,
1337 Reason => PE_Accessibility_Check_Failed));
1340 Error_Msg_Warn := SPARK_Mode /= On;
1341 Error_Msg_N ("cannot return a local value by reference<<", N);
1342 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1346 if Known_Null (Expr)
1347 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1348 and then Null_Exclusion_Present (Parent (Scope_Id))
1350 Apply_Compile_Time_Constraint_Error
1352 Msg => "(Ada 2005) null not allowed for "
1353 & "null-excluding return??",
1354 Reason => CE_Null_Not_Allowed);
1357 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1358 -- has no initializing expression.
1360 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1361 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1362 Subprogram_Access_Level (Scope_Id)
1365 ("level of return expression type is deeper than "
1366 & "class-wide function!", Obj_Decl);
1369 end Analyze_Function_Return;
1371 -------------------------------------
1372 -- Analyze_Generic_Subprogram_Body --
1373 -------------------------------------
1375 procedure Analyze_Generic_Subprogram_Body
1379 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1380 Kind : constant Entity_Kind := Ekind (Gen_Id);
1381 Body_Id : Entity_Id;
1386 -- Copy body and disable expansion while analyzing the generic For a
1387 -- stub, do not copy the stub (which would load the proper body), this
1388 -- will be done when the proper body is analyzed.
1390 if Nkind (N) /= N_Subprogram_Body_Stub then
1391 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1394 -- Once the contents of the generic copy and the template are
1395 -- swapped, do the same for their respective aspect specifications.
1397 Exchange_Aspects (N, New_N);
1399 -- Collect all contract-related source pragmas found within the
1400 -- template and attach them to the contract of the subprogram body.
1401 -- This contract is used in the capture of global references within
1404 Create_Generic_Contract (N);
1409 Spec := Specification (N);
1411 -- Within the body of the generic, the subprogram is callable, and
1412 -- behaves like the corresponding non-generic unit.
1414 Body_Id := Defining_Entity (Spec);
1416 if Kind = E_Generic_Procedure
1417 and then Nkind (Spec) /= N_Procedure_Specification
1419 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1422 elsif Kind = E_Generic_Function
1423 and then Nkind (Spec) /= N_Function_Specification
1425 Error_Msg_N ("invalid body for generic function ", Body_Id);
1429 Set_Corresponding_Body (Gen_Decl, Body_Id);
1431 if Has_Completion (Gen_Id)
1432 and then Nkind (Parent (N)) /= N_Subunit
1434 Error_Msg_N ("duplicate generic body", N);
1437 Set_Has_Completion (Gen_Id);
1440 if Nkind (N) = N_Subprogram_Body_Stub then
1441 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1443 Set_Corresponding_Spec (N, Gen_Id);
1446 if Nkind (Parent (N)) = N_Compilation_Unit then
1447 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1450 -- Make generic parameters immediately visible in the body. They are
1451 -- needed to process the formals declarations. Then make the formals
1452 -- visible in a separate step.
1454 Push_Scope (Gen_Id);
1458 First_Ent : Entity_Id;
1461 First_Ent := First_Entity (Gen_Id);
1464 while Present (E) and then not Is_Formal (E) loop
1469 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1471 -- Now generic formals are visible, and the specification can be
1472 -- analyzed, for subsequent conformance check.
1474 Body_Id := Analyze_Subprogram_Specification (Spec);
1476 -- Make formal parameters visible
1480 -- E is the first formal parameter, we loop through the formals
1481 -- installing them so that they will be visible.
1483 Set_First_Entity (Gen_Id, E);
1484 while Present (E) loop
1490 -- Visible generic entity is callable within its own body
1492 Set_Ekind (Gen_Id, Ekind (Body_Id));
1493 Set_Ekind (Body_Id, E_Subprogram_Body);
1494 Set_Convention (Body_Id, Convention (Gen_Id));
1495 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1496 Set_Scope (Body_Id, Scope (Gen_Id));
1498 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1500 if Nkind (N) = N_Subprogram_Body_Stub then
1502 -- No body to analyze, so restore state of generic unit
1504 Set_Ekind (Gen_Id, Kind);
1505 Set_Ekind (Body_Id, Kind);
1507 if Present (First_Ent) then
1508 Set_First_Entity (Gen_Id, First_Ent);
1515 -- If this is a compilation unit, it must be made visible explicitly,
1516 -- because the compilation of the declaration, unlike other library
1517 -- unit declarations, does not. If it is not a unit, the following
1518 -- is redundant but harmless.
1520 Set_Is_Immediately_Visible (Gen_Id);
1521 Reference_Body_Formals (Gen_Id, Body_Id);
1523 if Is_Child_Unit (Gen_Id) then
1524 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1527 Set_Actual_Subtypes (N, Current_Scope);
1529 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1530 Set_SPARK_Pragma_Inherited (Body_Id);
1532 -- Analyze any aspect specifications that appear on the generic
1535 if Has_Aspects (N) then
1536 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1539 Analyze_Declarations (Declarations (N));
1542 -- Process the contract of the subprogram body after all declarations
1543 -- have been analyzed. This ensures that any contract-related pragmas
1544 -- are available through the N_Contract node of the body.
1546 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1548 Analyze (Handled_Statement_Sequence (N));
1549 Save_Global_References (Original_Node (N));
1551 -- Prior to exiting the scope, include generic formals again (if any
1552 -- are present) in the set of local entities.
1554 if Present (First_Ent) then
1555 Set_First_Entity (Gen_Id, First_Ent);
1558 Check_References (Gen_Id);
1561 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1562 Update_Use_Clause_Chain;
1563 Validate_Categorization_Dependency (N, Gen_Id);
1565 Check_Subprogram_Order (N);
1567 -- Outside of its body, unit is generic again
1569 Set_Ekind (Gen_Id, Kind);
1570 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1573 Style.Check_Identifier (Body_Id, Gen_Id);
1577 end Analyze_Generic_Subprogram_Body;
1579 ----------------------------
1580 -- Analyze_Null_Procedure --
1581 ----------------------------
1583 procedure Analyze_Null_Procedure
1585 Is_Completion : out Boolean)
1587 Loc : constant Source_Ptr := Sloc (N);
1588 Spec : constant Node_Id := Specification (N);
1589 Designator : Entity_Id;
1591 Null_Body : Node_Id := Empty;
1592 Null_Stmt : Node_Id := Null_Statement (Spec);
1596 -- Capture the profile of the null procedure before analysis, for
1597 -- expansion at the freeze point and at each point of call. The body is
1598 -- used if the procedure has preconditions, or if it is a completion. In
1599 -- the first case the body is analyzed at the freeze point, in the other
1600 -- it replaces the null procedure declaration.
1602 -- For a null procedure that comes from source, a NULL statement is
1603 -- provided by the parser, which carries the source location of the
1604 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1605 -- from expansion, create one now.
1607 if No (Null_Stmt) then
1608 Null_Stmt := Make_Null_Statement (Loc);
1612 Make_Subprogram_Body (Loc,
1613 Specification => New_Copy_Tree (Spec),
1614 Declarations => New_List,
1615 Handled_Statement_Sequence =>
1616 Make_Handled_Sequence_Of_Statements (Loc,
1617 Statements => New_List (Null_Stmt)));
1619 -- Create new entities for body and formals
1621 Set_Defining_Unit_Name (Specification (Null_Body),
1622 Make_Defining_Identifier
1623 (Sloc (Defining_Entity (N)),
1624 Chars (Defining_Entity (N))));
1626 Form := First (Parameter_Specifications (Specification (Null_Body)));
1627 while Present (Form) loop
1628 Set_Defining_Identifier (Form,
1629 Make_Defining_Identifier
1630 (Sloc (Defining_Identifier (Form)),
1631 Chars (Defining_Identifier (Form))));
1635 -- Determine whether the null procedure may be a completion of a generic
1636 -- suprogram, in which case we use the new null body as the completion
1637 -- and set minimal semantic information on the original declaration,
1638 -- which is rewritten as a null statement.
1640 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1642 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1643 Insert_Before (N, Null_Body);
1644 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1646 Rewrite (N, Make_Null_Statement (Loc));
1647 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1648 Is_Completion := True;
1652 -- Resolve the types of the formals now, because the freeze point may
1653 -- appear in a different context, e.g. an instantiation.
1655 Form := First (Parameter_Specifications (Specification (Null_Body)));
1656 while Present (Form) loop
1657 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1658 Find_Type (Parameter_Type (Form));
1660 elsif No (Access_To_Subprogram_Definition
1661 (Parameter_Type (Form)))
1663 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1665 -- The case of a null procedure with a formal that is an
1666 -- access-to-subprogram type, and that is used as an actual
1667 -- in an instantiation is left to the enthusiastic reader.
1677 -- If there are previous overloadable entities with the same name, check
1678 -- whether any of them is completed by the null procedure.
1680 if Present (Prev) and then Is_Overloadable (Prev) then
1681 Designator := Analyze_Subprogram_Specification (Spec);
1682 Prev := Find_Corresponding_Spec (N);
1685 if No (Prev) or else not Comes_From_Source (Prev) then
1686 Designator := Analyze_Subprogram_Specification (Spec);
1687 Set_Has_Completion (Designator);
1689 -- Signal to caller that this is a procedure declaration
1691 Is_Completion := False;
1693 -- Null procedures are always inlined, but generic formal subprograms
1694 -- which appear as such in the internal instance of formal packages,
1695 -- need no completion and are not marked Inline.
1698 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1700 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1701 Set_Body_To_Inline (N, Null_Body);
1702 Set_Is_Inlined (Designator);
1706 -- The null procedure is a completion. We unconditionally rewrite
1707 -- this as a null body (even if expansion is not active), because
1708 -- there are various error checks that are applied on this body
1709 -- when it is analyzed (e.g. correct aspect placement).
1711 if Has_Completion (Prev) then
1712 Error_Msg_Sloc := Sloc (Prev);
1713 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1716 Check_Previous_Null_Procedure (N, Prev);
1718 Is_Completion := True;
1719 Rewrite (N, Null_Body);
1722 end Analyze_Null_Procedure;
1724 -----------------------------
1725 -- Analyze_Operator_Symbol --
1726 -----------------------------
1728 -- An operator symbol such as "+" or "and" may appear in context where the
1729 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1730 -- is just a string, as in (conjunction = "or"). In these cases the parser
1731 -- generates this node, and the semantics does the disambiguation. Other
1732 -- such case are actuals in an instantiation, the generic unit in an
1733 -- instantiation, and pragma arguments.
1735 procedure Analyze_Operator_Symbol (N : Node_Id) is
1736 Par : constant Node_Id := Parent (N);
1739 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1740 or else Nkind (Par) = N_Function_Instantiation
1741 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1742 or else (Nkind (Par) = N_Pragma_Argument_Association
1743 and then not Is_Pragma_String_Literal (Par))
1744 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1745 or else (Nkind (Par) = N_Attribute_Reference
1746 and then Attribute_Name (Par) /= Name_Value)
1748 Find_Direct_Name (N);
1751 Change_Operator_Symbol_To_String_Literal (N);
1754 end Analyze_Operator_Symbol;
1756 -----------------------------------
1757 -- Analyze_Parameter_Association --
1758 -----------------------------------
1760 procedure Analyze_Parameter_Association (N : Node_Id) is
1762 Analyze (Explicit_Actual_Parameter (N));
1763 end Analyze_Parameter_Association;
1765 ----------------------------
1766 -- Analyze_Procedure_Call --
1767 ----------------------------
1769 -- WARNING: This routine manages Ghost regions. Return statements must be
1770 -- replaced by gotos which jump to the end of the routine and restore the
1773 procedure Analyze_Procedure_Call (N : Node_Id) is
1774 procedure Analyze_Call_And_Resolve;
1775 -- Do Analyze and Resolve calls for procedure call. At the end, check
1776 -- for illegal order dependence.
1777 -- ??? where is the check for illegal order dependencies?
1779 ------------------------------
1780 -- Analyze_Call_And_Resolve --
1781 ------------------------------
1783 procedure Analyze_Call_And_Resolve is
1785 if Nkind (N) = N_Procedure_Call_Statement then
1787 Resolve (N, Standard_Void_Type);
1791 end Analyze_Call_And_Resolve;
1795 Actuals : constant List_Id := Parameter_Associations (N);
1796 Loc : constant Source_Ptr := Sloc (N);
1797 P : constant Node_Id := Name (N);
1799 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1800 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1801 -- Save the Ghost-related attributes to restore on exit
1806 -- Start of processing for Analyze_Procedure_Call
1809 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1810 -- a procedure call or an entry call. The prefix may denote an access
1811 -- to subprogram type, in which case an implicit dereference applies.
1812 -- If the prefix is an indexed component (without implicit dereference)
1813 -- then the construct denotes a call to a member of an entire family.
1814 -- If the prefix is a simple name, it may still denote a call to a
1815 -- parameterless member of an entry family. Resolution of these various
1816 -- interpretations is delicate.
1818 -- Do not analyze machine code statements to avoid rejecting them in
1821 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1822 Set_Etype (P, Standard_Void_Type);
1827 -- If this is a call of the form Obj.Op, the call may have been analyzed
1828 -- and possibly rewritten into a block, in which case we are done.
1830 if Analyzed (N) then
1833 -- If there is an error analyzing the name (which may have been
1834 -- rewritten if the original call was in prefix notation) then error
1835 -- has been emitted already, mark node and return.
1837 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1838 Set_Etype (N, Any_Type);
1842 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1843 -- Set the mode now to ensure that any nodes generated during analysis
1844 -- and expansion are properly marked as Ghost.
1846 Mark_And_Set_Ghost_Procedure_Call (N);
1848 -- Otherwise analyze the parameters
1850 if Present (Actuals) then
1851 Actual := First (Actuals);
1853 while Present (Actual) loop
1855 Check_Parameterless_Call (Actual);
1860 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1862 if Nkind (P) = N_Attribute_Reference
1863 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1865 Name_Elab_Subp_Body)
1867 if Present (Actuals) then
1869 ("no parameters allowed for this call", First (Actuals));
1873 Set_Etype (N, Standard_Void_Type);
1876 elsif Is_Entity_Name (P)
1877 and then Is_Record_Type (Etype (Entity (P)))
1878 and then Remote_AST_I_Dereference (P)
1882 elsif Is_Entity_Name (P)
1883 and then Ekind (Entity (P)) /= E_Entry_Family
1885 if Is_Access_Type (Etype (P))
1886 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1887 and then No (Actuals)
1888 and then Comes_From_Source (N)
1890 Error_Msg_N ("missing explicit dereference in call", N);
1893 Analyze_Call_And_Resolve;
1895 -- If the prefix is the simple name of an entry family, this is a
1896 -- parameterless call from within the task body itself.
1898 elsif Is_Entity_Name (P)
1899 and then Nkind (P) = N_Identifier
1900 and then Ekind (Entity (P)) = E_Entry_Family
1901 and then Present (Actuals)
1902 and then No (Next (First (Actuals)))
1904 -- Can be call to parameterless entry family. What appears to be the
1905 -- sole argument is in fact the entry index. Rewrite prefix of node
1906 -- accordingly. Source representation is unchanged by this
1910 Make_Indexed_Component (Loc,
1912 Make_Selected_Component (Loc,
1913 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1914 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1915 Expressions => Actuals);
1916 Set_Name (N, New_N);
1917 Set_Etype (New_N, Standard_Void_Type);
1918 Set_Parameter_Associations (N, No_List);
1919 Analyze_Call_And_Resolve;
1921 elsif Nkind (P) = N_Explicit_Dereference then
1922 if Ekind (Etype (P)) = E_Subprogram_Type then
1923 Analyze_Call_And_Resolve;
1925 Error_Msg_N ("expect access to procedure in call", P);
1928 -- The name can be a selected component or an indexed component that
1929 -- yields an access to subprogram. Such a prefix is legal if the call
1930 -- has parameter associations.
1932 elsif Is_Access_Type (Etype (P))
1933 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1935 if Present (Actuals) then
1936 Analyze_Call_And_Resolve;
1938 Error_Msg_N ("missing explicit dereference in call ", N);
1941 -- If not an access to subprogram, then the prefix must resolve to the
1942 -- name of an entry, entry family, or protected operation.
1944 -- For the case of a simple entry call, P is a selected component where
1945 -- the prefix is the task and the selector name is the entry. A call to
1946 -- a protected procedure will have the same syntax. If the protected
1947 -- object contains overloaded operations, the entity may appear as a
1948 -- function, the context will select the operation whose type is Void.
1950 elsif Nkind (P) = N_Selected_Component
1951 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1955 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1956 -- in prefix notation may still be missing its controlling argument,
1957 -- so perform the transformation now.
1959 if SPARK_Mode = On and then In_Inlined_Body then
1961 Subp : constant Entity_Id := Entity (Selector_Name (P));
1962 Typ : constant Entity_Id := Etype (Prefix (P));
1965 if Is_Tagged_Type (Typ)
1966 and then Present (First_Formal (Subp))
1967 and then (Etype (First_Formal (Subp)) = Typ
1969 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1970 and then Try_Object_Operation (P)
1975 Analyze_Call_And_Resolve;
1980 Analyze_Call_And_Resolve;
1983 elsif Nkind (P) = N_Selected_Component
1984 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1985 and then Present (Actuals)
1986 and then No (Next (First (Actuals)))
1988 -- Can be call to parameterless entry family. What appears to be the
1989 -- sole argument is in fact the entry index. Rewrite prefix of node
1990 -- accordingly. Source representation is unchanged by this
1994 Make_Indexed_Component (Loc,
1995 Prefix => New_Copy (P),
1996 Expressions => Actuals);
1997 Set_Name (N, New_N);
1998 Set_Etype (New_N, Standard_Void_Type);
1999 Set_Parameter_Associations (N, No_List);
2000 Analyze_Call_And_Resolve;
2002 -- For the case of a reference to an element of an entry family, P is
2003 -- an indexed component whose prefix is a selected component (task and
2004 -- entry family), and whose index is the entry family index.
2006 elsif Nkind (P) = N_Indexed_Component
2007 and then Nkind (Prefix (P)) = N_Selected_Component
2008 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
2010 Analyze_Call_And_Resolve;
2012 -- If the prefix is the name of an entry family, it is a call from
2013 -- within the task body itself.
2015 elsif Nkind (P) = N_Indexed_Component
2016 and then Nkind (Prefix (P)) = N_Identifier
2017 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
2020 Make_Selected_Component (Loc,
2022 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
2023 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
2024 Rewrite (Prefix (P), New_N);
2026 Analyze_Call_And_Resolve;
2028 -- In Ada 2012. a qualified expression is a name, but it cannot be a
2029 -- procedure name, so the construct can only be a qualified expression.
2031 elsif Nkind (P) = N_Qualified_Expression
2032 and then Ada_Version >= Ada_2012
2034 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
2037 -- Anything else is an error
2040 Error_Msg_N ("invalid procedure or entry call", N);
2044 Restore_Ghost_Region (Saved_GM, Saved_IGR);
2045 end Analyze_Procedure_Call;
2047 ------------------------------
2048 -- Analyze_Return_Statement --
2049 ------------------------------
2051 procedure Analyze_Return_Statement (N : Node_Id) is
2052 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2053 N_Simple_Return_Statement));
2055 Returns_Object : constant Boolean :=
2056 Nkind (N) = N_Extended_Return_Statement
2058 (Nkind (N) = N_Simple_Return_Statement
2059 and then Present (Expression (N)));
2060 -- True if we're returning something; that is, "return <expression>;"
2061 -- or "return Result : T [:= ...]". False for "return;". Used for error
2062 -- checking: If Returns_Object is True, N should apply to a function
2063 -- body; otherwise N should apply to a procedure body, entry body,
2064 -- accept statement, or extended return statement.
2066 function Find_What_It_Applies_To return Entity_Id;
2067 -- Find the entity representing the innermost enclosing body, accept
2068 -- statement, or extended return statement. If the result is a callable
2069 -- construct or extended return statement, then this will be the value
2070 -- of the Return_Applies_To attribute. Otherwise, the program is
2071 -- illegal. See RM-6.5(4/2).
2073 -----------------------------
2074 -- Find_What_It_Applies_To --
2075 -----------------------------
2077 function Find_What_It_Applies_To return Entity_Id is
2078 Result : Entity_Id := Empty;
2081 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2082 -- and postconditions.
2084 for J in reverse 0 .. Scope_Stack.Last loop
2085 Result := Scope_Stack.Table (J).Entity;
2086 exit when not Ekind_In (Result, E_Block, E_Loop)
2087 and then Chars (Result) /= Name_uPostconditions;
2090 pragma Assert (Present (Result));
2092 end Find_What_It_Applies_To;
2094 -- Local declarations
2096 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2097 Kind : constant Entity_Kind := Ekind (Scope_Id);
2098 Loc : constant Source_Ptr := Sloc (N);
2099 Stm_Entity : constant Entity_Id :=
2101 (E_Return_Statement, Current_Scope, Loc, 'R');
2103 -- Start of processing for Analyze_Return_Statement
2106 Set_Return_Statement_Entity (N, Stm_Entity);
2108 Set_Etype (Stm_Entity, Standard_Void_Type);
2109 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2111 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2112 -- (4/2): an inner return statement will apply to this extended return.
2114 if Nkind (N) = N_Extended_Return_Statement then
2115 Push_Scope (Stm_Entity);
2118 -- Check that pragma No_Return is obeyed. Don't complain about the
2119 -- implicitly-generated return that is placed at the end.
2121 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2122 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2125 -- Warn on any unassigned OUT parameters if in procedure
2127 if Ekind (Scope_Id) = E_Procedure then
2128 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2131 -- Check that functions return objects, and other things do not
2133 if Kind = E_Function or else Kind = E_Generic_Function then
2134 if not Returns_Object then
2135 Error_Msg_N ("missing expression in return from function", N);
2138 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2139 if Returns_Object then
2140 Error_Msg_N ("procedure cannot return value (use function)", N);
2143 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2144 if Returns_Object then
2145 if Is_Protected_Type (Scope (Scope_Id)) then
2146 Error_Msg_N ("entry body cannot return value", N);
2148 Error_Msg_N ("accept statement cannot return value", N);
2152 elsif Kind = E_Return_Statement then
2154 -- We are nested within another return statement, which must be an
2155 -- extended_return_statement.
2157 if Returns_Object then
2158 if Nkind (N) = N_Extended_Return_Statement then
2160 ("extended return statement cannot be nested (use `RETURN;`)",
2163 -- Case of a simple return statement with a value inside extended
2164 -- return statement.
2168 ("return nested in extended return statement cannot return "
2169 & "value (use `RETURN;`)", N);
2174 Error_Msg_N ("illegal context for return statement", N);
2177 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2178 Analyze_Function_Return (N);
2180 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2181 Set_Return_Present (Scope_Id);
2184 if Nkind (N) = N_Extended_Return_Statement then
2188 Kill_Current_Values (Last_Assignment_Only => True);
2189 Check_Unreachable_Code (N);
2191 Analyze_Dimension (N);
2192 end Analyze_Return_Statement;
2194 -------------------------------------
2195 -- Analyze_Simple_Return_Statement --
2196 -------------------------------------
2198 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2200 if Present (Expression (N)) then
2201 Mark_Coextensions (N, Expression (N));
2204 Analyze_Return_Statement (N);
2205 end Analyze_Simple_Return_Statement;
2207 -------------------------
2208 -- Analyze_Return_Type --
2209 -------------------------
2211 procedure Analyze_Return_Type (N : Node_Id) is
2212 Designator : constant Entity_Id := Defining_Entity (N);
2213 Typ : Entity_Id := Empty;
2216 -- Normal case where result definition does not indicate an error
2218 if Result_Definition (N) /= Error then
2219 if Nkind (Result_Definition (N)) = N_Access_Definition then
2220 Check_SPARK_05_Restriction
2221 ("access result is not allowed", Result_Definition (N));
2223 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2226 AD : constant Node_Id :=
2227 Access_To_Subprogram_Definition (Result_Definition (N));
2229 if Present (AD) and then Protected_Present (AD) then
2230 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2232 Typ := Access_Definition (N, Result_Definition (N));
2236 Set_Parent (Typ, Result_Definition (N));
2237 Set_Is_Local_Anonymous_Access (Typ);
2238 Set_Etype (Designator, Typ);
2240 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2242 Null_Exclusion_Static_Checks (N);
2244 -- Subtype_Mark case
2247 Find_Type (Result_Definition (N));
2248 Typ := Entity (Result_Definition (N));
2249 Set_Etype (Designator, Typ);
2251 -- Unconstrained array as result is not allowed in SPARK
2253 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2254 Check_SPARK_05_Restriction
2255 ("returning an unconstrained array is not allowed",
2256 Result_Definition (N));
2259 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2261 Null_Exclusion_Static_Checks (N);
2263 -- If a null exclusion is imposed on the result type, then create
2264 -- a null-excluding itype (an access subtype) and use it as the
2265 -- function's Etype. Note that the null exclusion checks are done
2266 -- right before this, because they don't get applied to types that
2267 -- do not come from source.
2269 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2270 Set_Etype (Designator,
2271 Create_Null_Excluding_Itype
2274 Scope_Id => Scope (Current_Scope)));
2276 -- The new subtype must be elaborated before use because
2277 -- it is visible outside of the function. However its base
2278 -- type may not be frozen yet, so the reference that will
2279 -- force elaboration must be attached to the freezing of
2282 -- If the return specification appears on a proper body,
2283 -- the subtype will have been created already on the spec.
2285 if Is_Frozen (Typ) then
2286 if Nkind (Parent (N)) = N_Subprogram_Body
2287 and then Nkind (Parent (Parent (N))) = N_Subunit
2291 Build_Itype_Reference (Etype (Designator), Parent (N));
2295 Ensure_Freeze_Node (Typ);
2298 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2300 Set_Itype (IR, Etype (Designator));
2301 Append_Freeze_Actions (Typ, New_List (IR));
2306 Set_Etype (Designator, Typ);
2309 if Ekind (Typ) = E_Incomplete_Type
2310 or else (Is_Class_Wide_Type (Typ)
2311 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2313 -- AI05-0151: Tagged incomplete types are allowed in all formal
2314 -- parts. Untagged incomplete types are not allowed in bodies.
2315 -- As a consequence, limited views cannot appear in a basic
2316 -- declaration that is itself within a body, because there is
2317 -- no point at which the non-limited view will become visible.
2319 if Ada_Version >= Ada_2012 then
2320 if From_Limited_With (Typ) and then In_Package_Body then
2322 ("invalid use of incomplete type&",
2323 Result_Definition (N), Typ);
2325 -- The return type of a subprogram body cannot be of a
2326 -- formal incomplete type.
2328 elsif Is_Generic_Type (Typ)
2329 and then Nkind (Parent (N)) = N_Subprogram_Body
2332 ("return type cannot be a formal incomplete type",
2333 Result_Definition (N));
2335 elsif Is_Class_Wide_Type (Typ)
2336 and then Is_Generic_Type (Root_Type (Typ))
2337 and then Nkind (Parent (N)) = N_Subprogram_Body
2340 ("return type cannot be a formal incomplete type",
2341 Result_Definition (N));
2343 elsif Is_Tagged_Type (Typ) then
2346 -- Use is legal in a thunk generated for an operation
2347 -- inherited from a progenitor.
2349 elsif Is_Thunk (Designator)
2350 and then Present (Non_Limited_View (Typ))
2354 elsif Nkind (Parent (N)) = N_Subprogram_Body
2355 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2359 ("invalid use of untagged incomplete type&",
2363 -- The type must be completed in the current package. This
2364 -- is checked at the end of the package declaration when
2365 -- Taft-amendment types are identified. If the return type
2366 -- is class-wide, there is no required check, the type can
2367 -- be a bona fide TAT.
2369 if Ekind (Scope (Current_Scope)) = E_Package
2370 and then In_Private_Part (Scope (Current_Scope))
2371 and then not Is_Class_Wide_Type (Typ)
2373 Append_Elmt (Designator, Private_Dependents (Typ));
2378 ("invalid use of incomplete type&", Designator, Typ);
2383 -- Case where result definition does indicate an error
2386 Set_Etype (Designator, Any_Type);
2388 end Analyze_Return_Type;
2390 -----------------------------
2391 -- Analyze_Subprogram_Body --
2392 -----------------------------
2394 procedure Analyze_Subprogram_Body (N : Node_Id) is
2395 Loc : constant Source_Ptr := Sloc (N);
2396 Body_Spec : constant Node_Id := Specification (N);
2397 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2400 if Debug_Flag_C then
2401 Write_Str ("==> subprogram body ");
2402 Write_Name (Chars (Body_Id));
2403 Write_Str (" from ");
2404 Write_Location (Loc);
2409 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2411 -- The real work is split out into the helper, so it can do "return;"
2412 -- without skipping the debug output:
2414 Analyze_Subprogram_Body_Helper (N);
2416 if Debug_Flag_C then
2418 Write_Str ("<== subprogram body ");
2419 Write_Name (Chars (Body_Id));
2420 Write_Str (" from ");
2421 Write_Location (Loc);
2424 end Analyze_Subprogram_Body;
2426 ------------------------------------
2427 -- Analyze_Subprogram_Body_Helper --
2428 ------------------------------------
2430 -- This procedure is called for regular subprogram bodies, generic bodies,
2431 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2432 -- specification matters, and is used to create a proper declaration for
2433 -- the subprogram, or to perform conformance checks.
2435 -- WARNING: This routine manages Ghost regions. Return statements must be
2436 -- replaced by gotos which jump to the end of the routine and restore the
2439 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2440 Body_Spec : Node_Id := Specification (N);
2441 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2442 Loc : constant Source_Ptr := Sloc (N);
2443 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2445 Conformant : Boolean;
2446 Desig_View : Entity_Id := Empty;
2447 Exch_Views : Elist_Id := No_Elist;
2449 Mask_Types : Elist_Id := No_Elist;
2450 Prot_Typ : Entity_Id := Empty;
2451 Spec_Decl : Node_Id := Empty;
2452 Spec_Id : Entity_Id;
2454 Last_Real_Spec_Entity : Entity_Id := Empty;
2455 -- When we analyze a separate spec, the entity chain ends up containing
2456 -- the formals, as well as any itypes generated during analysis of the
2457 -- default expressions for parameters, or the arguments of associated
2458 -- precondition/postcondition pragmas (which are analyzed in the context
2459 -- of the spec since they have visibility on formals).
2461 -- These entities belong with the spec and not the body. However we do
2462 -- the analysis of the body in the context of the spec (again to obtain
2463 -- visibility to the formals), and all the entities generated during
2464 -- this analysis end up also chained to the entity chain of the spec.
2465 -- But they really belong to the body, and there is circuitry to move
2466 -- them from the spec to the body.
2468 -- However, when we do this move, we don't want to move the real spec
2469 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2470 -- variable points to the last real spec entity, so we only move those
2471 -- chained beyond that point. It is initialized to Empty to deal with
2472 -- the case where there is no separate spec.
2474 function Body_Has_Contract return Boolean;
2475 -- Check whether unanalyzed body has an aspect or pragma that may
2476 -- generate a SPARK contract.
2478 function Body_Has_SPARK_Mode_On return Boolean;
2479 -- Check whether SPARK_Mode On applies to the subprogram body, either
2480 -- because it is specified directly on the body, or because it is
2481 -- inherited from the enclosing subprogram or package.
2483 procedure Build_Subprogram_Declaration;
2484 -- Create a matching subprogram declaration for subprogram body N
2486 procedure Check_Anonymous_Return;
2487 -- Ada 2005: if a function returns an access type that denotes a task,
2488 -- or a type that contains tasks, we must create a master entity for
2489 -- the anonymous type, which typically will be used in an allocator
2490 -- in the body of the function.
2492 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2493 -- Look ahead to recognize a pragma that may appear after the body.
2494 -- If there is a previous spec, check that it appears in the same
2495 -- declarative part. If the pragma is Inline_Always, perform inlining
2496 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2497 -- If the body acts as a spec, and inlining is required, we create a
2498 -- subprogram declaration for it, in order to attach the body to inline.
2499 -- If pragma does not appear after the body, check whether there is
2500 -- an inline pragma before any local declarations.
2502 procedure Check_Missing_Return;
2503 -- Checks for a function with a no return statements, and also performs
2504 -- the warning checks implemented by Check_Returns. In formal mode, also
2505 -- verify that a function ends with a RETURN and that a procedure does
2506 -- not contain any RETURN.
2508 function Disambiguate_Spec return Entity_Id;
2509 -- When a primitive is declared between the private view and the full
2510 -- view of a concurrent type which implements an interface, a special
2511 -- mechanism is used to find the corresponding spec of the primitive
2514 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2515 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2516 -- incomplete types coming from a limited context and replace their
2517 -- limited views with the non-limited ones. Return the list of changes
2518 -- to be used to undo the transformation.
2520 function Is_Private_Concurrent_Primitive
2521 (Subp_Id : Entity_Id) return Boolean;
2522 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2523 -- type that implements an interface and has a private view.
2525 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2526 -- N is the body generated for an expression function that is not a
2527 -- completion and Spec_Id the defining entity of its spec. Mark all
2528 -- the not-yet-frozen types referenced by the simple return statement
2529 -- of the function as formally frozen.
2531 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2532 -- Undo the transformation done by Exchange_Limited_Views.
2534 procedure Set_Trivial_Subprogram (N : Node_Id);
2535 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2536 -- subprogram whose body is being analyzed. N is the statement node
2537 -- causing the flag to be set, if the following statement is a return
2538 -- of an entity, we mark the entity as set in source to suppress any
2539 -- warning on the stylized use of function stubs with a dummy return.
2541 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2542 -- Undo the transformation done by Mask_Unfrozen_Types
2544 procedure Verify_Overriding_Indicator;
2545 -- If there was a previous spec, the entity has been entered in the
2546 -- current scope previously. If the body itself carries an overriding
2547 -- indicator, check that it is consistent with the known status of the
2550 -----------------------
2551 -- Body_Has_Contract --
2552 -----------------------
2554 function Body_Has_Contract return Boolean is
2555 Decls : constant List_Id := Declarations (N);
2559 -- Check for aspects that may generate a contract
2561 if Present (Aspect_Specifications (N)) then
2562 Item := First (Aspect_Specifications (N));
2563 while Present (Item) loop
2564 if Is_Subprogram_Contract_Annotation (Item) then
2572 -- Check for pragmas that may generate a contract
2574 if Present (Decls) then
2575 Item := First (Decls);
2576 while Present (Item) loop
2577 if Nkind (Item) = N_Pragma
2578 and then Is_Subprogram_Contract_Annotation (Item)
2588 end Body_Has_Contract;
2590 ----------------------------
2591 -- Body_Has_SPARK_Mode_On --
2592 ----------------------------
2594 function Body_Has_SPARK_Mode_On return Boolean is
2595 Decls : constant List_Id := Declarations (N);
2599 -- Check for SPARK_Mode aspect
2601 if Present (Aspect_Specifications (N)) then
2602 Item := First (Aspect_Specifications (N));
2603 while Present (Item) loop
2604 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2605 return Get_SPARK_Mode_From_Annotation (Item) = On;
2612 -- Check for SPARK_Mode pragma
2614 if Present (Decls) then
2615 Item := First (Decls);
2616 while Present (Item) loop
2618 -- Pragmas that apply to a subprogram body are usually grouped
2619 -- together. Look for a potential pragma SPARK_Mode among them.
2621 if Nkind (Item) = N_Pragma then
2622 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2623 return Get_SPARK_Mode_From_Annotation (Item) = On;
2626 -- Otherwise the first non-pragma declarative item terminates
2627 -- the region where pragma SPARK_Mode may appear.
2637 -- Otherwise, the applicable SPARK_Mode is inherited from the
2638 -- enclosing subprogram or package.
2640 return SPARK_Mode = On;
2641 end Body_Has_SPARK_Mode_On;
2643 ----------------------------------
2644 -- Build_Subprogram_Declaration --
2645 ----------------------------------
2647 procedure Build_Subprogram_Declaration is
2648 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2649 -- Relocate certain categorization pragmas from the declarative list
2650 -- of subprogram body From and insert them after node To. The pragmas
2653 -- Volatile_Function
2654 -- Also copy pragma SPARK_Mode if present in the declarative list
2655 -- of subprogram body From and insert it after node To. This pragma
2656 -- should not be moved, as it applies to the body too.
2662 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2664 Next_Decl : Node_Id;
2667 pragma Assert (Nkind (From) = N_Subprogram_Body);
2669 -- The destination node must be part of a list, as the pragmas are
2670 -- inserted after it.
2672 pragma Assert (Is_List_Member (To));
2674 -- Inspect the declarations of the subprogram body looking for
2675 -- specific pragmas.
2677 Decl := First (Declarations (N));
2678 while Present (Decl) loop
2679 Next_Decl := Next (Decl);
2681 if Nkind (Decl) = N_Pragma then
2682 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2683 Insert_After (To, New_Copy_Tree (Decl));
2685 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2687 Name_Volatile_Function)
2690 Insert_After (To, Decl);
2701 Subp_Decl : Node_Id;
2703 -- Start of processing for Build_Subprogram_Declaration
2706 -- Create a matching subprogram spec using the profile of the body.
2707 -- The structure of the tree is identical, but has new entities for
2708 -- the defining unit name and formal parameters.
2711 Make_Subprogram_Declaration (Loc,
2712 Specification => Copy_Subprogram_Spec (Body_Spec));
2713 Set_Comes_From_Source (Subp_Decl, True);
2715 -- Also mark parameters as coming from source
2717 if Present (Parameter_Specifications (Specification (Subp_Decl))) then
2722 First (Parameter_Specifications (Specification (Subp_Decl)));
2724 while Present (Form) loop
2725 Set_Comes_From_Source (Defining_Identifier (Form), True);
2731 -- Relocate the aspects and relevant pragmas from the subprogram body
2732 -- to the generated spec because it acts as the initial declaration.
2734 Insert_Before (N, Subp_Decl);
2735 Move_Aspects (N, To => Subp_Decl);
2736 Move_Pragmas (N, To => Subp_Decl);
2738 -- Ensure that the generated corresponding spec and original body
2739 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2740 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2741 -- correctly set for local subprograms.
2743 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2745 Analyze (Subp_Decl);
2747 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2748 -- the body since the expander may generate calls using that entity.
2749 -- Required to ensure that Expand_Call rewrites calls to this
2750 -- function by calls to the built procedure.
2752 if Modify_Tree_For_C
2753 and then Nkind (Body_Spec) = N_Function_Specification
2755 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2757 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2758 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2759 Corresponding_Procedure
2760 (Defining_Entity (Specification (Subp_Decl))));
2763 -- Analyze any relocated source pragmas or pragmas created for aspect
2766 Decl := Next (Subp_Decl);
2767 while Present (Decl) loop
2769 -- Stop the search for pragmas once the body has been reached as
2770 -- this terminates the region where pragmas may appear.
2775 elsif Nkind (Decl) = N_Pragma then
2782 Spec_Id := Defining_Entity (Subp_Decl);
2783 Set_Corresponding_Spec (N, Spec_Id);
2785 -- Mark the generated spec as a source construct to ensure that all
2786 -- calls to it are properly registered in ALI files for GNATprove.
2788 Set_Comes_From_Source (Spec_Id, True);
2790 -- Ensure that the specs of the subprogram declaration and its body
2791 -- are identical, otherwise they will appear non-conformant due to
2792 -- rewritings in the default values of formal parameters.
2794 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2795 Set_Specification (N, Body_Spec);
2796 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2797 end Build_Subprogram_Declaration;
2799 ----------------------------
2800 -- Check_Anonymous_Return --
2801 ----------------------------
2803 procedure Check_Anonymous_Return is
2809 if Present (Spec_Id) then
2815 if Ekind (Scop) = E_Function
2816 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2817 and then not Is_Thunk (Scop)
2819 -- Skip internally built functions which handle the case of
2820 -- a null access (see Expand_Interface_Conversion)
2822 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2823 and then not Comes_From_Source (Parent (Scop)))
2825 and then (Has_Task (Designated_Type (Etype (Scop)))
2827 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2829 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2830 and then Expander_Active
2832 -- Avoid cases with no tasking support
2834 and then RTE_Available (RE_Current_Master)
2835 and then not Restriction_Active (No_Task_Hierarchy)
2838 Make_Object_Declaration (Loc,
2839 Defining_Identifier =>
2840 Make_Defining_Identifier (Loc, Name_uMaster),
2841 Constant_Present => True,
2842 Object_Definition =>
2843 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2845 Make_Explicit_Dereference (Loc,
2846 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2848 if Present (Declarations (N)) then
2849 Prepend (Decl, Declarations (N));
2851 Set_Declarations (N, New_List (Decl));
2854 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2855 Set_Has_Master_Entity (Scop);
2857 -- Now mark the containing scope as a task master
2860 while Nkind (Par) /= N_Compilation_Unit loop
2861 Par := Parent (Par);
2862 pragma Assert (Present (Par));
2864 -- If we fall off the top, we are at the outer level, and
2865 -- the environment task is our effective master, so nothing
2869 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2871 Set_Is_Task_Master (Par, True);
2876 end Check_Anonymous_Return;
2878 -------------------------
2879 -- Check_Inline_Pragma --
2880 -------------------------
2882 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2886 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2887 -- True when N is a pragma Inline or Inline_Always that applies
2888 -- to this subprogram.
2890 -----------------------
2891 -- Is_Inline_Pragma --
2892 -----------------------
2894 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2896 if Nkind (N) = N_Pragma
2898 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2899 or else (Pragma_Name_Unmapped (N) = Name_Inline
2901 (Front_End_Inlining or else Optimization_Level > 0)))
2902 and then Present (Pragma_Argument_Associations (N))
2905 Pragma_Arg : Node_Id :=
2906 Expression (First (Pragma_Argument_Associations (N)));
2908 if Nkind (Pragma_Arg) = N_Selected_Component then
2909 Pragma_Arg := Selector_Name (Pragma_Arg);
2912 return Chars (Pragma_Arg) = Chars (Body_Id);
2918 end Is_Inline_Pragma;
2920 -- Start of processing for Check_Inline_Pragma
2923 if not Expander_Active then
2927 if Is_List_Member (N)
2928 and then Present (Next (N))
2929 and then Is_Inline_Pragma (Next (N))
2933 elsif Nkind (N) /= N_Subprogram_Body_Stub
2934 and then Present (Declarations (N))
2935 and then Is_Inline_Pragma (First (Declarations (N)))
2937 Prag := First (Declarations (N));
2943 if Present (Prag) then
2944 if Present (Spec_Id) then
2945 if Is_List_Member (N)
2946 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2947 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2953 -- Create a subprogram declaration, to make treatment uniform.
2954 -- Make the sloc of the subprogram name that of the entity in
2955 -- the body, so that style checks find identical strings.
2958 Subp : constant Entity_Id :=
2959 Make_Defining_Identifier
2960 (Sloc (Body_Id), Chars (Body_Id));
2961 Decl : constant Node_Id :=
2962 Make_Subprogram_Declaration (Loc,
2964 New_Copy_Tree (Specification (N)));
2967 -- Link the body and the generated spec
2969 Set_Corresponding_Body (Decl, Body_Id);
2970 Set_Corresponding_Spec (N, Subp);
2972 Set_Defining_Unit_Name (Specification (Decl), Subp);
2974 -- To ensure proper coverage when body is inlined, indicate
2975 -- whether the subprogram comes from source.
2977 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2979 if Present (First_Formal (Body_Id)) then
2980 Plist := Copy_Parameter_List (Body_Id);
2981 Set_Parameter_Specifications
2982 (Specification (Decl), Plist);
2985 -- Move aspects to the new spec
2987 if Has_Aspects (N) then
2988 Move_Aspects (N, To => Decl);
2991 Insert_Before (N, Decl);
2994 Set_Has_Pragma_Inline (Subp);
2996 if Pragma_Name (Prag) = Name_Inline_Always then
2997 Set_Is_Inlined (Subp);
2998 Set_Has_Pragma_Inline_Always (Subp);
3001 -- Prior to copying the subprogram body to create a template
3002 -- for it for subsequent inlining, remove the pragma from
3003 -- the current body so that the copy that will produce the
3004 -- new body will start from a completely unanalyzed tree.
3006 if Nkind (Parent (Prag)) = N_Subprogram_Body then
3007 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
3014 end Check_Inline_Pragma;
3016 --------------------------
3017 -- Check_Missing_Return --
3018 --------------------------
3020 procedure Check_Missing_Return is
3022 Missing_Ret : Boolean;
3025 if Nkind (Body_Spec) = N_Function_Specification then
3026 if Present (Spec_Id) then
3032 if Return_Present (Id) then
3033 Check_Returns (HSS, 'F', Missing_Ret);
3036 Set_Has_Missing_Return (Id);
3039 -- Within a premature instantiation of a package with no body, we
3040 -- build completions of the functions therein, with a Raise
3041 -- statement. No point in complaining about a missing return in
3044 elsif Ekind (Id) = E_Function
3045 and then In_Instance
3046 and then Present (Statements (HSS))
3047 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3051 elsif Is_Generic_Subprogram (Id)
3052 or else not Is_Machine_Code_Subprogram (Id)
3054 Error_Msg_N ("missing RETURN statement in function body", N);
3057 -- If procedure with No_Return, check returns
3059 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3060 if Present (Spec_Id) then
3066 if No_Return (Id) then
3067 Check_Returns (HSS, 'P', Missing_Ret, Id);
3071 -- Special checks in SPARK mode
3073 if Nkind (Body_Spec) = N_Function_Specification then
3075 -- In SPARK mode, last statement of a function should be a return
3078 Stat : constant Node_Id := Last_Source_Statement (HSS);
3081 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3082 N_Extended_Return_Statement)
3084 Check_SPARK_05_Restriction
3085 ("last statement in function should be RETURN", Stat);
3089 -- In SPARK mode, verify that a procedure has no return
3091 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3092 if Present (Spec_Id) then
3098 -- Would be nice to point to return statement here, can we
3099 -- borrow the Check_Returns procedure here ???
3101 if Return_Present (Id) then
3102 Check_SPARK_05_Restriction
3103 ("procedure should not have RETURN", N);
3106 end Check_Missing_Return;
3108 -----------------------
3109 -- Disambiguate_Spec --
3110 -----------------------
3112 function Disambiguate_Spec return Entity_Id is
3113 Priv_Spec : Entity_Id;
3116 procedure Replace_Types (To_Corresponding : Boolean);
3117 -- Depending on the flag, replace the type of formal parameters of
3118 -- Body_Id if it is a concurrent type implementing interfaces with
3119 -- the corresponding record type or the other way around.
3121 procedure Replace_Types (To_Corresponding : Boolean) is
3123 Formal_Typ : Entity_Id;
3126 Formal := First_Formal (Body_Id);
3127 while Present (Formal) loop
3128 Formal_Typ := Etype (Formal);
3130 if Is_Class_Wide_Type (Formal_Typ) then
3131 Formal_Typ := Root_Type (Formal_Typ);
3134 -- From concurrent type to corresponding record
3136 if To_Corresponding then
3137 if Is_Concurrent_Type (Formal_Typ)
3138 and then Present (Corresponding_Record_Type (Formal_Typ))
3141 (Corresponding_Record_Type (Formal_Typ)))
3144 Corresponding_Record_Type (Formal_Typ));
3147 -- From corresponding record to concurrent type
3150 if Is_Concurrent_Record_Type (Formal_Typ)
3151 and then Present (Interfaces (Formal_Typ))
3154 Corresponding_Concurrent_Type (Formal_Typ));
3158 Next_Formal (Formal);
3162 -- Start of processing for Disambiguate_Spec
3165 -- Try to retrieve the specification of the body as is. All error
3166 -- messages are suppressed because the body may not have a spec in
3167 -- its current state.
3169 Spec_N := Find_Corresponding_Spec (N, False);
3171 -- It is possible that this is the body of a primitive declared
3172 -- between a private and a full view of a concurrent type. The
3173 -- controlling parameter of the spec carries the concurrent type,
3174 -- not the corresponding record type as transformed by Analyze_
3175 -- Subprogram_Specification. In such cases, we undo the change
3176 -- made by the analysis of the specification and try to find the
3179 -- Note that wrappers already have their corresponding specs and
3180 -- bodies set during their creation, so if the candidate spec is
3181 -- a wrapper, then we definitely need to swap all types to their
3182 -- original concurrent status.
3185 or else Is_Primitive_Wrapper (Spec_N)
3187 -- Restore all references of corresponding record types to the
3188 -- original concurrent types.
3190 Replace_Types (To_Corresponding => False);
3191 Priv_Spec := Find_Corresponding_Spec (N, False);
3193 -- The current body truly belongs to a primitive declared between
3194 -- a private and a full view. We leave the modified body as is,
3195 -- and return the true spec.
3197 if Present (Priv_Spec)
3198 and then Is_Private_Primitive (Priv_Spec)
3203 -- In case that this is some sort of error, restore the original
3204 -- state of the body.
3206 Replace_Types (To_Corresponding => True);
3210 end Disambiguate_Spec;
3212 ----------------------------
3213 -- Exchange_Limited_Views --
3214 ----------------------------
3216 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3217 Result : Elist_Id := No_Elist;
3219 procedure Detect_And_Exchange (Id : Entity_Id);
3220 -- Determine whether Id's type denotes an incomplete type associated
3221 -- with a limited with clause and exchange the limited view with the
3222 -- non-limited one when available. Note that the non-limited view
3223 -- may exist because of a with_clause in another unit in the context,
3224 -- but cannot be used because the current view of the enclosing unit
3225 -- is still a limited view.
3227 -------------------------
3228 -- Detect_And_Exchange --
3229 -------------------------
3231 procedure Detect_And_Exchange (Id : Entity_Id) is
3232 Typ : constant Entity_Id := Etype (Id);
3234 if From_Limited_With (Typ)
3235 and then Has_Non_Limited_View (Typ)
3236 and then not From_Limited_With (Scope (Typ))
3239 Result := New_Elmt_List;
3242 Prepend_Elmt (Typ, Result);
3243 Prepend_Elmt (Id, Result);
3244 Set_Etype (Id, Non_Limited_View (Typ));
3246 end Detect_And_Exchange;
3252 -- Start of processing for Exchange_Limited_Views
3255 -- Do not process subprogram bodies as they already use the non-
3256 -- limited view of types.
3258 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3262 -- Examine all formals and swap views when applicable
3264 Formal := First_Formal (Subp_Id);
3265 while Present (Formal) loop
3266 Detect_And_Exchange (Formal);
3268 Next_Formal (Formal);
3271 -- Process the return type of a function
3273 if Ekind (Subp_Id) = E_Function then
3274 Detect_And_Exchange (Subp_Id);
3278 end Exchange_Limited_Views;
3280 -------------------------------------
3281 -- Is_Private_Concurrent_Primitive --
3282 -------------------------------------
3284 function Is_Private_Concurrent_Primitive
3285 (Subp_Id : Entity_Id) return Boolean
3287 Formal_Typ : Entity_Id;
3290 if Present (First_Formal (Subp_Id)) then
3291 Formal_Typ := Etype (First_Formal (Subp_Id));
3293 if Is_Concurrent_Record_Type (Formal_Typ) then
3294 if Is_Class_Wide_Type (Formal_Typ) then
3295 Formal_Typ := Root_Type (Formal_Typ);
3298 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3301 -- The type of the first formal is a concurrent tagged type with
3305 Is_Concurrent_Type (Formal_Typ)
3306 and then Is_Tagged_Type (Formal_Typ)
3307 and then Has_Private_Declaration (Formal_Typ);
3311 end Is_Private_Concurrent_Primitive;
3313 -------------------------
3314 -- Mask_Unfrozen_Types --
3315 -------------------------
3317 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3318 Result : Elist_Id := No_Elist;
3320 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3321 -- Mask all types referenced in the subtree rooted at Node
3323 --------------------
3324 -- Mask_Type_Refs --
3325 --------------------
3327 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3328 procedure Mask_Type (Typ : Entity_Id);
3329 -- ??? what does this do?
3335 procedure Mask_Type (Typ : Entity_Id) is
3337 -- Skip Itypes created by the preanalysis
3340 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3345 if not Is_Frozen (Typ) then
3346 Set_Is_Frozen (Typ);
3347 Append_New_Elmt (Typ, Result);
3351 -- Start of processing for Mask_Type_Refs
3354 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3355 Mask_Type (Etype (Entity (Node)));
3357 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3358 Mask_Type (Scope (Entity (Node)));
3361 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3362 and then Present (Etype (Node))
3364 Mask_Type (Etype (Node));
3370 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3374 Return_Stmt : constant Node_Id :=
3375 First (Statements (Handled_Statement_Sequence (N)));
3377 -- Start of processing for Mask_Unfrozen_Types
3380 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3382 Mask_References (Expression (Return_Stmt));
3385 end Mask_Unfrozen_Types;
3387 ---------------------------
3388 -- Restore_Limited_Views --
3389 ---------------------------
3391 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3392 Elmt : Elmt_Id := First_Elmt (Restore_List);
3396 while Present (Elmt) loop
3399 Set_Etype (Id, Node (Elmt));
3402 end Restore_Limited_Views;
3404 ----------------------------
3405 -- Set_Trivial_Subprogram --
3406 ----------------------------
3408 procedure Set_Trivial_Subprogram (N : Node_Id) is
3409 Nxt : constant Node_Id := Next (N);
3412 Set_Is_Trivial_Subprogram (Body_Id);
3414 if Present (Spec_Id) then
3415 Set_Is_Trivial_Subprogram (Spec_Id);
3419 and then Nkind (Nxt) = N_Simple_Return_Statement
3420 and then No (Next (Nxt))
3421 and then Present (Expression (Nxt))
3422 and then Is_Entity_Name (Expression (Nxt))
3424 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3426 end Set_Trivial_Subprogram;
3428 ---------------------------
3429 -- Unmask_Unfrozen_Types --
3430 ---------------------------
3432 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3433 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3436 while Present (Elmt) loop
3437 Set_Is_Frozen (Node (Elmt), False);
3440 end Unmask_Unfrozen_Types;
3442 ---------------------------------
3443 -- Verify_Overriding_Indicator --
3444 ---------------------------------
3446 procedure Verify_Overriding_Indicator is
3448 if Must_Override (Body_Spec) then
3449 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3450 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3454 elsif not Present (Overridden_Operation (Spec_Id)) then
3456 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3458 -- Overriding indicators aren't allowed for protected subprogram
3459 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3460 -- this to a warning if -gnatd.E is enabled.
3462 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3463 Error_Msg_Warn := Error_To_Warning;
3465 ("<<overriding indicator not allowed for protected "
3466 & "subprogram body", Body_Spec);
3469 elsif Must_Not_Override (Body_Spec) then
3470 if Present (Overridden_Operation (Spec_Id)) then
3472 ("subprogram& overrides inherited operation",
3473 Body_Spec, Spec_Id);
3475 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3476 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3479 ("subprogram& overrides predefined operator ",
3480 Body_Spec, Spec_Id);
3482 -- Overriding indicators aren't allowed for protected subprogram
3483 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3484 -- this to a warning if -gnatd.E is enabled.
3486 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3487 Error_Msg_Warn := Error_To_Warning;
3490 ("<<overriding indicator not allowed "
3491 & "for protected subprogram body", Body_Spec);
3493 -- If this is not a primitive operation, then the overriding
3494 -- indicator is altogether illegal.
3496 elsif not Is_Primitive (Spec_Id) then
3498 ("overriding indicator only allowed "
3499 & "if subprogram is primitive", Body_Spec);
3502 -- If checking the style rule and the operation overrides, then
3503 -- issue a warning about a missing overriding_indicator. Protected
3504 -- subprogram bodies are excluded from this style checking, since
3505 -- they aren't primitives (even though their declarations can
3506 -- override) and aren't allowed to have an overriding_indicator.
3509 and then Present (Overridden_Operation (Spec_Id))
3510 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3512 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3513 Style.Missing_Overriding (N, Body_Id);
3516 and then Can_Override_Operator (Spec_Id)
3517 and then not In_Predefined_Unit (Spec_Id)
3519 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3520 Style.Missing_Overriding (N, Body_Id);
3522 end Verify_Overriding_Indicator;
3526 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3527 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3528 Saved_ISMP : constant Boolean :=
3529 Ignore_SPARK_Mode_Pragmas_In_Instance;
3530 -- Save the Ghost and SPARK mode-related data to restore on exit
3532 -- Start of processing for Analyze_Subprogram_Body_Helper
3535 -- A [generic] subprogram body freezes the contract of the nearest
3536 -- enclosing package body and all other contracts encountered in the
3537 -- same declarative part up to and excluding the subprogram body:
3539 -- package body Nearest_Enclosing_Package
3540 -- with Refined_State => (State => Constit)
3544 -- procedure Freezes_Enclosing_Package_Body
3545 -- with Refined_Depends => (Input => Constit) ...
3547 -- This ensures that any annotations referenced by the contract of the
3548 -- [generic] subprogram body are available. This form of freezing is
3549 -- decoupled from the usual Freeze_xxx mechanism because it must also
3550 -- work in the context of generics where normal freezing is disabled.
3552 -- Only bodies coming from source should cause this type of freezing.
3553 -- Expression functions that act as bodies and complete an initial
3554 -- declaration must be included in this category, hence the use of
3557 if Comes_From_Source (Original_Node (N)) then
3558 Freeze_Previous_Contracts (N);
3561 -- Generic subprograms are handled separately. They always have a
3562 -- generic specification. Determine whether current scope has a
3563 -- previous declaration.
3565 -- If the subprogram body is defined within an instance of the same
3566 -- name, the instance appears as a package renaming, and will be hidden
3567 -- within the subprogram.
3569 if Present (Prev_Id)
3570 and then not Is_Overloadable (Prev_Id)
3571 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3572 or else Comes_From_Source (Prev_Id))
3574 if Is_Generic_Subprogram (Prev_Id) then
3577 -- A subprogram body is Ghost when it is stand alone and subject
3578 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3579 -- the mode now to ensure that any nodes generated during analysis
3580 -- and expansion are properly marked as Ghost.
3582 Mark_And_Set_Ghost_Body (N, Spec_Id);
3584 -- If the body completes the initial declaration of a compilation
3585 -- unit which is subject to pragma Elaboration_Checks, set the
3586 -- model specified by the pragma because it applies to all parts
3589 Install_Elaboration_Model (Spec_Id);
3591 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3592 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3594 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3596 if Nkind (N) = N_Subprogram_Body then
3597 HSS := Handled_Statement_Sequence (N);
3598 Check_Missing_Return;
3603 -- Otherwise a previous entity conflicts with the subprogram name.
3604 -- Attempting to enter name will post error.
3607 Enter_Name (Body_Id);
3611 -- Non-generic case, find the subprogram declaration, if one was seen,
3612 -- or enter new overloaded entity in the current scope. If the
3613 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3614 -- part of the context of one of its subunits. No need to redo the
3617 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3621 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3623 if Nkind (N) = N_Subprogram_Body_Stub
3624 or else No (Corresponding_Spec (N))
3626 if Is_Private_Concurrent_Primitive (Body_Id) then
3627 Spec_Id := Disambiguate_Spec;
3629 -- A subprogram body is Ghost when it is stand alone and
3630 -- subject to pragma Ghost or when the corresponding spec is
3631 -- Ghost. Set the mode now to ensure that any nodes generated
3632 -- during analysis and expansion are properly marked as Ghost.
3634 Mark_And_Set_Ghost_Body (N, Spec_Id);
3636 -- If the body completes a compilation unit which is subject
3637 -- to pragma Elaboration_Checks, set the model specified by
3638 -- the pragma because it applies to all parts of the unit.
3640 Install_Elaboration_Model (Spec_Id);
3643 Spec_Id := Find_Corresponding_Spec (N);
3645 -- A subprogram body is Ghost when it is stand alone and
3646 -- subject to pragma Ghost or when the corresponding spec is
3647 -- Ghost. Set the mode now to ensure that any nodes generated
3648 -- during analysis and expansion are properly marked as Ghost.
3650 Mark_And_Set_Ghost_Body (N, Spec_Id);
3652 -- If the body completes a compilation unit which is subject
3653 -- to pragma Elaboration_Checks, set the model specified by
3654 -- the pragma because it applies to all parts of the unit.
3656 Install_Elaboration_Model (Spec_Id);
3658 -- In GNATprove mode, if the body has no previous spec, create
3659 -- one so that the inlining machinery can operate properly.
3660 -- Transfer aspects, if any, to the new spec, so that they
3661 -- are legal and can be processed ahead of the body.
3662 -- We make two copies of the given spec, one for the new
3663 -- declaration, and one for the body.
3665 if No (Spec_Id) and then GNATprove_Mode
3667 -- Inlining does not apply during preanalysis of code
3669 and then Full_Analysis
3671 -- Inlining only applies to full bodies, not stubs
3673 and then Nkind (N) /= N_Subprogram_Body_Stub
3675 -- Inlining only applies to bodies in the source code, not to
3676 -- those generated by the compiler. In particular, expression
3677 -- functions, whose body is generated by the compiler, are
3678 -- treated specially by GNATprove.
3680 and then Comes_From_Source (Body_Id)
3682 -- This cannot be done for a compilation unit, which is not
3683 -- in a context where we can insert a new spec.
3685 and then Is_List_Member (N)
3687 -- Inlining only applies to subprograms without contracts,
3688 -- as a contract is a sign that GNATprove should perform a
3689 -- modular analysis of the subprogram instead of a contextual
3690 -- analysis at each call site. The same test is performed in
3691 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3692 -- here in another form (because the contract has not been
3693 -- attached to the body) to avoid front-end errors in case
3694 -- pragmas are used instead of aspects, because the
3695 -- corresponding pragmas in the body would not be transferred
3696 -- to the spec, leading to legality errors.
3698 and then not Body_Has_Contract
3699 and then not Inside_A_Generic
3701 Build_Subprogram_Declaration;
3703 -- If this is a function that returns a constrained array, and
3704 -- we are generating SPARK_For_C, create subprogram declaration
3705 -- to simplify subsequent C generation.
3708 and then Modify_Tree_For_C
3709 and then Nkind (Body_Spec) = N_Function_Specification
3710 and then Is_Array_Type (Etype (Body_Id))
3711 and then Is_Constrained (Etype (Body_Id))
3713 Build_Subprogram_Declaration;
3717 -- If this is a duplicate body, no point in analyzing it
3719 if Error_Posted (N) then
3723 -- A subprogram body should cause freezing of its own declaration,
3724 -- but if there was no previous explicit declaration, then the
3725 -- subprogram will get frozen too late (there may be code within
3726 -- the body that depends on the subprogram having been frozen,
3727 -- such as uses of extra formals), so we force it to be frozen
3728 -- here. Same holds if the body and spec are compilation units.
3729 -- Finally, if the return type is an anonymous access to protected
3730 -- subprogram, it must be frozen before the body because its
3731 -- expansion has generated an equivalent type that is used when
3732 -- elaborating the body.
3734 -- An exception in the case of Ada 2012, AI05-177: The bodies
3735 -- created for expression functions do not freeze.
3738 and then Nkind (Original_Node (N)) /= N_Expression_Function
3740 Freeze_Before (N, Body_Id);
3742 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3743 Freeze_Before (N, Spec_Id);
3745 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3746 Freeze_Before (N, Etype (Body_Id));
3750 Spec_Id := Corresponding_Spec (N);
3752 -- A subprogram body is Ghost when it is stand alone and subject
3753 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3754 -- the mode now to ensure that any nodes generated during analysis
3755 -- and expansion are properly marked as Ghost.
3757 Mark_And_Set_Ghost_Body (N, Spec_Id);
3759 -- If the body completes the initial declaration of a compilation
3760 -- unit which is subject to pragma Elaboration_Checks, set the
3761 -- model specified by the pragma because it applies to all parts
3764 Install_Elaboration_Model (Spec_Id);
3768 -- Previously we scanned the body to look for nested subprograms, and
3769 -- rejected an inline directive if nested subprograms were present,
3770 -- because the back-end would generate conflicting symbols for the
3771 -- nested bodies. This is now unnecessary.
3773 -- Look ahead to recognize a pragma Inline that appears after the body
3775 Check_Inline_Pragma (Spec_Id);
3777 -- Deal with special case of a fully private operation in the body of
3778 -- the protected type. We must create a declaration for the subprogram,
3779 -- in order to attach the protected subprogram that will be used in
3780 -- internal calls. We exclude compiler generated bodies from the
3781 -- expander since the issue does not arise for those cases.
3784 and then Comes_From_Source (N)
3785 and then Is_Protected_Type (Current_Scope)
3787 Spec_Id := Build_Private_Protected_Declaration (N);
3790 -- If we are generating C and this is a function returning a constrained
3791 -- array type for which we must create a procedure with an extra out
3792 -- parameter, build and analyze the body now. The procedure declaration
3793 -- has already been created. We reuse the source body of the function,
3794 -- because in an instance it may contain global references that cannot
3795 -- be reanalyzed. The source function itself is not used any further,
3796 -- so we mark it as having a completion. If the subprogram is a stub the
3797 -- transformation is done later, when the proper body is analyzed.
3800 and then Modify_Tree_For_C
3801 and then Present (Spec_Id)
3802 and then Ekind (Spec_Id) = E_Function
3803 and then Nkind (N) /= N_Subprogram_Body_Stub
3804 and then Rewritten_For_C (Spec_Id)
3806 Set_Has_Completion (Spec_Id);
3808 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3811 -- The entity for the created procedure must remain invisible, so it
3812 -- does not participate in resolution of subsequent references to the
3815 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3819 -- If a separate spec is present, then deal with freezing issues
3821 if Present (Spec_Id) then
3822 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3823 Verify_Overriding_Indicator;
3825 -- In general, the spec will be frozen when we start analyzing the
3826 -- body. However, for internally generated operations, such as
3827 -- wrapper functions for inherited operations with controlling
3828 -- results, the spec may not have been frozen by the time we expand
3829 -- the freeze actions that include the bodies. In particular, extra
3830 -- formals for accessibility or for return-in-place may need to be
3831 -- generated. Freeze nodes, if any, are inserted before the current
3832 -- body. These freeze actions are also needed in ASIS mode and in
3833 -- Compile_Only mode to enable the proper back-end type annotations.
3834 -- They are necessary in any case to insure order of elaboration
3837 if not Is_Frozen (Spec_Id)
3838 and then (Expander_Active
3840 or else (Operating_Mode = Check_Semantics
3841 and then Serious_Errors_Detected = 0))
3843 -- The body generated for an expression function that is not a
3844 -- completion is a freeze point neither for the profile nor for
3845 -- anything else. That's why, in order to prevent any freezing
3846 -- during analysis, we need to mask types declared outside the
3847 -- expression that are not yet frozen.
3849 if Nkind (N) = N_Subprogram_Body
3850 and then Was_Expression_Function (N)
3851 and then not Has_Completion (Spec_Id)
3853 Set_Is_Frozen (Spec_Id);
3854 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3856 Set_Has_Delayed_Freeze (Spec_Id);
3857 Freeze_Before (N, Spec_Id);
3862 -- If the subprogram has a class-wide clone, build its body as a copy
3863 -- of the original body, and rewrite body of original subprogram as a
3864 -- wrapper that calls the clone. If N is a stub, this construction will
3865 -- take place when the proper body is analyzed.
3867 if Present (Spec_Id)
3868 and then Present (Class_Wide_Clone (Spec_Id))
3869 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3870 and then Nkind (N) /= N_Subprogram_Body_Stub
3872 Build_Class_Wide_Clone_Body (Spec_Id, N);
3874 -- This is the new body for the existing primitive operation
3876 Rewrite (N, Build_Class_Wide_Clone_Call
3877 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3878 Set_Has_Completion (Spec_Id, False);
3883 -- Place subprogram on scope stack, and make formals visible. If there
3884 -- is a spec, the visible entity remains that of the spec.
3886 if Present (Spec_Id) then
3887 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3889 if Is_Child_Unit (Spec_Id) then
3890 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3894 Style.Check_Identifier (Body_Id, Spec_Id);
3897 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3898 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3900 if Is_Abstract_Subprogram (Spec_Id) then
3901 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3905 Set_Convention (Body_Id, Convention (Spec_Id));
3906 Set_Has_Completion (Spec_Id);
3908 if Is_Protected_Type (Scope (Spec_Id)) then
3909 Prot_Typ := Scope (Spec_Id);
3912 -- If this is a body generated for a renaming, do not check for
3913 -- full conformance. The check is redundant, because the spec of
3914 -- the body is a copy of the spec in the renaming declaration,
3915 -- and the test can lead to spurious errors on nested defaults.
3917 if Present (Spec_Decl)
3918 and then not Comes_From_Source (N)
3920 (Nkind (Original_Node (Spec_Decl)) =
3921 N_Subprogram_Renaming_Declaration
3922 or else (Present (Corresponding_Body (Spec_Decl))
3924 Nkind (Unit_Declaration_Node
3925 (Corresponding_Body (Spec_Decl))) =
3926 N_Subprogram_Renaming_Declaration))
3930 -- Conversely, the spec may have been generated for specless body
3931 -- with an inline pragma. The entity comes from source, which is
3932 -- both semantically correct and necessary for proper inlining.
3933 -- The subprogram declaration itself is not in the source.
3935 elsif Comes_From_Source (N)
3936 and then Present (Spec_Decl)
3937 and then not Comes_From_Source (Spec_Decl)
3938 and then Has_Pragma_Inline (Spec_Id)
3945 Fully_Conformant, True, Conformant, Body_Id);
3948 -- If the body is not fully conformant, we have to decide if we
3949 -- should analyze it or not. If it has a really messed up profile
3950 -- then we probably should not analyze it, since we will get too
3951 -- many bogus messages.
3953 -- Our decision is to go ahead in the non-fully conformant case
3954 -- only if it is at least mode conformant with the spec. Note
3955 -- that the call to Check_Fully_Conformant has issued the proper
3956 -- error messages to complain about the lack of conformance.
3959 and then not Mode_Conformant (Body_Id, Spec_Id)
3965 -- In the case we are dealing with an expression function we check
3966 -- the formals attached to the spec instead of the body - so we don't
3967 -- reference body formals.
3969 if Spec_Id /= Body_Id
3970 and then not Is_Expression_Function (Spec_Id)
3972 Reference_Body_Formals (Spec_Id, Body_Id);
3975 Set_Ekind (Body_Id, E_Subprogram_Body);
3977 if Nkind (N) = N_Subprogram_Body_Stub then
3978 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3983 Set_Corresponding_Spec (N, Spec_Id);
3985 -- Ada 2005 (AI-345): If the operation is a primitive operation
3986 -- of a concurrent type, the type of the first parameter has been
3987 -- replaced with the corresponding record, which is the proper
3988 -- run-time structure to use. However, within the body there may
3989 -- be uses of the formals that depend on primitive operations
3990 -- of the type (in particular calls in prefixed form) for which
3991 -- we need the original concurrent type. The operation may have
3992 -- several controlling formals, so the replacement must be done
3995 if Comes_From_Source (Spec_Id)
3996 and then Present (First_Entity (Spec_Id))
3997 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3998 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3999 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
4000 and then Present (Corresponding_Concurrent_Type
4001 (Etype (First_Entity (Spec_Id))))
4004 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
4008 Form := First_Formal (Spec_Id);
4009 while Present (Form) loop
4010 if Etype (Form) = Typ then
4011 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
4019 -- Make the formals visible, and place subprogram on scope stack.
4020 -- This is also the point at which we set Last_Real_Spec_Entity
4021 -- to mark the entities which will not be moved to the body.
4023 Install_Formals (Spec_Id);
4024 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
4026 -- Within an instance, add local renaming declarations so that
4027 -- gdb can retrieve the values of actuals more easily. This is
4028 -- only relevant if generating code (and indeed we definitely
4029 -- do not want these definitions -gnatc mode, because that would
4032 if Is_Generic_Instance (Spec_Id)
4033 and then Is_Wrapper_Package (Current_Scope)
4034 and then Expander_Active
4036 Build_Subprogram_Instance_Renamings (N, Current_Scope);
4039 Push_Scope (Spec_Id);
4041 -- Make sure that the subprogram is immediately visible. For
4042 -- child units that have no separate spec this is indispensable.
4043 -- Otherwise it is safe albeit redundant.
4045 Set_Is_Immediately_Visible (Spec_Id);
4048 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
4049 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
4050 Set_Scope (Body_Id, Scope (Spec_Id));
4052 -- Case of subprogram body with no previous spec
4055 -- Check for style warning required
4059 -- Only apply check for source level subprograms for which checks
4060 -- have not been suppressed.
4062 and then Comes_From_Source (Body_Id)
4063 and then not Suppress_Style_Checks (Body_Id)
4065 -- No warnings within an instance
4067 and then not In_Instance
4069 -- No warnings for expression functions
4071 and then Nkind (Original_Node (N)) /= N_Expression_Function
4073 Style.Body_With_No_Spec (N);
4076 New_Overloaded_Entity (Body_Id);
4078 if Nkind (N) /= N_Subprogram_Body_Stub then
4079 Set_Acts_As_Spec (N);
4080 Generate_Definition (Body_Id);
4082 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
4084 -- If the body is an entry wrapper created for an entry with
4085 -- preconditions, it must be compiled in the context of the
4086 -- enclosing synchronized object, because it may mention other
4087 -- operations of the type.
4089 if Is_Entry_Wrapper (Body_Id) then
4091 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4094 Install_Declarations (Prot);
4098 Install_Formals (Body_Id);
4100 Push_Scope (Body_Id);
4103 -- For stubs and bodies with no previous spec, generate references to
4106 Generate_Reference_To_Formals (Body_Id);
4109 -- Entry barrier functions are generated outside the protected type and
4110 -- should not carry the SPARK_Mode of the enclosing context.
4112 if Nkind (N) = N_Subprogram_Body
4113 and then Is_Entry_Barrier_Function (N)
4117 -- The body is generated as part of expression function expansion. When
4118 -- the expression function appears in the visible declarations of a
4119 -- package, the body is added to the private declarations. Since both
4120 -- declarative lists may be subject to a different SPARK_Mode, inherit
4121 -- the mode of the spec.
4123 -- package P with SPARK_Mode is
4124 -- function Expr_Func ... is (...); -- original
4125 -- [function Expr_Func ...;] -- generated spec
4128 -- pragma SPARK_Mode (Off);
4129 -- [function Expr_Func ... is return ...;] -- generated body
4130 -- end P; -- mode is ON
4132 elsif not Comes_From_Source (N)
4133 and then Present (Spec_Id)
4134 and then Is_Expression_Function (Spec_Id)
4136 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4137 Set_SPARK_Pragma_Inherited
4138 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4140 -- Set the SPARK_Mode from the current context (may be overwritten later
4141 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4142 -- initially on a stand-alone subprogram body, but is then relocated to
4143 -- a generated corresponding spec. In this scenario the mode is shared
4144 -- between the spec and body.
4146 elsif No (SPARK_Pragma (Body_Id)) then
4147 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4148 Set_SPARK_Pragma_Inherited (Body_Id);
4151 -- A subprogram body may be instantiated or inlined at a later pass.
4152 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4153 -- applied to the initial declaration of the body.
4155 if Present (Spec_Id) then
4156 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4157 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4161 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4162 -- case the body is instantiated or inlined later and out of context.
4163 -- The body uses this attribute to restore the value of the global
4166 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4167 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4169 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4170 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4174 -- Preserve relevant elaboration-related attributes of the context which
4175 -- are no longer available or very expensive to recompute once analysis,
4176 -- resolution, and expansion are over.
4178 if No (Spec_Id) then
4179 Mark_Elaboration_Attributes
4185 -- If this is the proper body of a stub, we must verify that the stub
4186 -- conforms to the body, and to the previous spec if one was present.
4187 -- We know already that the body conforms to that spec. This test is
4188 -- only required for subprograms that come from source.
4190 if Nkind (Parent (N)) = N_Subunit
4191 and then Comes_From_Source (N)
4192 and then not Error_Posted (Body_Id)
4193 and then Nkind (Corresponding_Stub (Parent (N))) =
4194 N_Subprogram_Body_Stub
4197 Old_Id : constant Entity_Id :=
4199 (Specification (Corresponding_Stub (Parent (N))));
4201 Conformant : Boolean := False;
4204 if No (Spec_Id) then
4205 Check_Fully_Conformant (Body_Id, Old_Id);
4209 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4211 if not Conformant then
4213 -- The stub was taken to be a new declaration. Indicate that
4216 Set_Has_Completion (Old_Id, False);
4222 Set_Has_Completion (Body_Id);
4223 Check_Eliminated (Body_Id);
4225 -- Analyze any aspect specifications that appear on the subprogram body
4226 -- stub. Stop the analysis now as the stub does not have a declarative
4227 -- or a statement part, and it cannot be inlined.
4229 if Nkind (N) = N_Subprogram_Body_Stub then
4230 if Has_Aspects (N) then
4231 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4239 -- Note: Normally we don't do any inlining if expansion is off, since
4240 -- we won't generate code in any case. An exception arises in GNATprove
4241 -- mode where we want to expand some calls in place, even with expansion
4242 -- disabled, since the inlining eases formal verification.
4244 if not GNATprove_Mode
4245 and then Expander_Active
4246 and then Serious_Errors_Detected = 0
4247 and then Present (Spec_Id)
4248 and then Has_Pragma_Inline (Spec_Id)
4250 -- Legacy implementation (relying on front-end inlining)
4252 if not Back_End_Inlining then
4253 if (Has_Pragma_Inline_Always (Spec_Id)
4254 and then not Opt.Disable_FE_Inline_Always)
4255 or else (Front_End_Inlining
4256 and then not Opt.Disable_FE_Inline)
4258 Build_Body_To_Inline (N, Spec_Id);
4261 -- New implementation (relying on back-end inlining)
4264 if Has_Pragma_Inline_Always (Spec_Id)
4265 or else Optimization_Level > 0
4267 -- Handle function returning an unconstrained type
4269 if Comes_From_Source (Body_Id)
4270 and then Ekind (Spec_Id) = E_Function
4271 and then Returns_Unconstrained_Type (Spec_Id)
4273 -- If function builds in place, i.e. returns a limited type,
4274 -- inlining cannot be done.
4276 and then not Is_Limited_Type (Etype (Spec_Id))
4278 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4282 Subp_Body : constant Node_Id :=
4283 Unit_Declaration_Node (Body_Id);
4284 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4287 -- Do not pass inlining to the backend if the subprogram
4288 -- has declarations or statements which cannot be inlined
4289 -- by the backend. This check is done here to emit an
4290 -- error instead of the generic warning message reported
4291 -- by the GCC backend (ie. "function might not be
4294 if Present (Subp_Decl)
4295 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4299 elsif Has_Excluded_Statement
4302 (Handled_Statement_Sequence (Subp_Body)))
4306 -- If the backend inlining is available then at this
4307 -- stage we only have to mark the subprogram as inlined.
4308 -- The expander will take care of registering it in the
4309 -- table of subprograms inlined by the backend a part of
4310 -- processing calls to it (cf. Expand_Call)
4313 Set_Is_Inlined (Spec_Id);
4320 -- In GNATprove mode, inline only when there is a separate subprogram
4321 -- declaration for now, as inlining of subprogram bodies acting as
4322 -- declarations, or subprogram stubs, are not supported by front-end
4323 -- inlining. This inlining should occur after analysis of the body, so
4324 -- that it is known whether the value of SPARK_Mode, which can be
4325 -- defined by a pragma inside the body, is applicable to the body.
4326 -- Inlining can be disabled with switch -gnatdm
4328 elsif GNATprove_Mode
4329 and then Full_Analysis
4330 and then not Inside_A_Generic
4331 and then Present (Spec_Id)
4333 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4334 and then Body_Has_SPARK_Mode_On
4335 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4336 and then not Body_Has_Contract
4337 and then not Debug_Flag_M
4339 Build_Body_To_Inline (N, Spec_Id);
4342 -- When generating code, inherited pre/postconditions are handled when
4343 -- expanding the corresponding contract.
4345 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4346 -- of the specification we have to install the private withed units.
4347 -- This holds for child units as well.
4349 if Is_Compilation_Unit (Body_Id)
4350 or else Nkind (Parent (N)) = N_Compilation_Unit
4352 Install_Private_With_Clauses (Body_Id);
4355 Check_Anonymous_Return;
4357 -- Set the Protected_Formal field of each extra formal of the protected
4358 -- subprogram to reference the corresponding extra formal of the
4359 -- subprogram that implements it. For regular formals this occurs when
4360 -- the protected subprogram's declaration is expanded, but the extra
4361 -- formals don't get created until the subprogram is frozen. We need to
4362 -- do this before analyzing the protected subprogram's body so that any
4363 -- references to the original subprogram's extra formals will be changed
4364 -- refer to the implementing subprogram's formals (see Expand_Formal).
4366 if Present (Spec_Id)
4367 and then Is_Protected_Type (Scope (Spec_Id))
4368 and then Present (Protected_Body_Subprogram (Spec_Id))
4371 Impl_Subp : constant Entity_Id :=
4372 Protected_Body_Subprogram (Spec_Id);
4373 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4374 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4377 while Present (Prot_Ext_Formal) loop
4378 pragma Assert (Present (Impl_Ext_Formal));
4379 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4380 Next_Formal_With_Extras (Prot_Ext_Formal);
4381 Next_Formal_With_Extras (Impl_Ext_Formal);
4386 -- Now we can go on to analyze the body
4388 HSS := Handled_Statement_Sequence (N);
4389 Set_Actual_Subtypes (N, Current_Scope);
4391 -- Add a declaration for the Protection object, renaming declarations
4392 -- for discriminals and privals and finally a declaration for the entry
4393 -- family index (if applicable). This form of early expansion is done
4394 -- when the Expander is active because Install_Private_Data_Declarations
4395 -- references entities which were created during regular expansion. The
4396 -- subprogram entity must come from source, and not be an internally
4397 -- generated subprogram.
4400 and then Present (Prot_Typ)
4401 and then Present (Spec_Id)
4402 and then Comes_From_Source (Spec_Id)
4403 and then not Is_Eliminated (Spec_Id)
4405 Install_Private_Data_Declarations
4406 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4409 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4410 -- may now appear in parameter and result profiles. Since the analysis
4411 -- of a subprogram body may use the parameter and result profile of the
4412 -- spec, swap any limited views with their non-limited counterpart.
4414 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4415 Exch_Views := Exchange_Limited_Views (Spec_Id);
4418 -- If the return type is an anonymous access type whose designated type
4419 -- is the limited view of a class-wide type and the non-limited view is
4420 -- available, update the return type accordingly.
4422 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4428 Rtyp := Etype (Spec_Id);
4430 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4431 Etyp := Directly_Designated_Type (Rtyp);
4433 if Is_Class_Wide_Type (Etyp)
4434 and then From_Limited_With (Etyp)
4437 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4443 -- Analyze any aspect specifications that appear on the subprogram body
4445 if Has_Aspects (N) then
4446 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4449 Analyze_Declarations (Declarations (N));
4451 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4453 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4454 if Present (SPARK_Pragma (Spec_Id)) then
4455 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4457 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4459 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4460 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4461 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4463 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4466 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4470 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4471 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4472 Error_Msg_Sloc := Sloc (Spec_Id);
4474 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4478 -- A subprogram body freezes its own contract. Analyze the contract
4479 -- after the declarations of the body have been processed as pragmas
4480 -- are now chained on the contract of the subprogram body.
4482 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4484 -- Check completion, and analyze the statements
4487 Inspect_Deferred_Constant_Completion (Declarations (N));
4490 -- Deal with end of scope processing for the body
4492 Process_End_Label (HSS, 't', Current_Scope);
4493 Update_Use_Clause_Chain;
4496 -- If we are compiling an entry wrapper, remove the enclosing
4497 -- synchronized object from the stack.
4499 if Is_Entry_Wrapper (Body_Id) then
4503 Check_Subprogram_Order (N);
4504 Set_Analyzed (Body_Id);
4506 -- If we have a separate spec, then the analysis of the declarations
4507 -- caused the entities in the body to be chained to the spec id, but
4508 -- we want them chained to the body id. Only the formal parameters
4509 -- end up chained to the spec id in this case.
4511 if Present (Spec_Id) then
4513 -- We must conform to the categorization of our spec
4515 Validate_Categorization_Dependency (N, Spec_Id);
4517 -- And if this is a child unit, the parent units must conform
4519 if Is_Child_Unit (Spec_Id) then
4520 Validate_Categorization_Dependency
4521 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4524 -- Here is where we move entities from the spec to the body
4526 -- Case where there are entities that stay with the spec
4528 if Present (Last_Real_Spec_Entity) then
4530 -- No body entities (happens when the only real spec entities come
4531 -- from precondition and postcondition pragmas).
4533 if No (Last_Entity (Body_Id)) then
4534 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4536 -- Body entities present (formals), so chain stuff past them
4540 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4543 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4544 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4545 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4547 -- Case where there are no spec entities, in this case there can be
4548 -- no body entities either, so just move everything.
4550 -- If the body is generated for an expression function, it may have
4551 -- been preanalyzed already, if 'access was applied to it.
4554 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4555 N_Expression_Function
4557 pragma Assert (No (Last_Entity (Body_Id)));
4561 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4562 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4563 Set_First_Entity (Spec_Id, Empty);
4564 Set_Last_Entity (Spec_Id, Empty);
4567 -- Otherwise the body does not complete a previous declaration. Check
4568 -- the categorization of the body against the units it withs.
4571 Validate_Categorization_Dependency (N, Body_Id);
4574 Check_Missing_Return;
4576 -- Now we are going to check for variables that are never modified in
4577 -- the body of the procedure. But first we deal with a special case
4578 -- where we want to modify this check. If the body of the subprogram
4579 -- starts with a raise statement or its equivalent, or if the body
4580 -- consists entirely of a null statement, then it is pretty obvious that
4581 -- it is OK to not reference the parameters. For example, this might be
4582 -- the following common idiom for a stubbed function: statement of the
4583 -- procedure raises an exception. In particular this deals with the
4584 -- common idiom of a stubbed function, which appears something like:
4586 -- function F (A : Integer) return Some_Type;
4589 -- raise Program_Error;
4593 -- Here the purpose of X is simply to satisfy the annoying requirement
4594 -- in Ada that there be at least one return, and we certainly do not
4595 -- want to go posting warnings on X that it is not initialized. On
4596 -- the other hand, if X is entirely unreferenced that should still
4599 -- What we do is to detect these cases, and if we find them, flag the
4600 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4601 -- suppress unwanted warnings. For the case of the function stub above
4602 -- we have a special test to set X as apparently assigned to suppress
4609 -- Skip call markers installed by the ABE mechanism, labels, and
4610 -- Push_xxx_Error_Label to find the first real statement.
4612 Stm := First (Statements (HSS));
4613 while Nkind_In (Stm, N_Call_Marker, N_Label)
4614 or else Nkind (Stm) in N_Push_xxx_Label
4619 -- Do the test on the original statement before expansion
4622 Ostm : constant Node_Id := Original_Node (Stm);
4625 -- If explicit raise statement, turn on flag
4627 if Nkind (Ostm) = N_Raise_Statement then
4628 Set_Trivial_Subprogram (Stm);
4630 -- If null statement, and no following statements, turn on flag
4632 elsif Nkind (Stm) = N_Null_Statement
4633 and then Comes_From_Source (Stm)
4634 and then No (Next (Stm))
4636 Set_Trivial_Subprogram (Stm);
4638 -- Check for explicit call cases which likely raise an exception
4640 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4641 if Is_Entity_Name (Name (Ostm)) then
4643 Ent : constant Entity_Id := Entity (Name (Ostm));
4646 -- If the procedure is marked No_Return, then likely it
4647 -- raises an exception, but in any case it is not coming
4648 -- back here, so turn on the flag.
4651 and then Ekind (Ent) = E_Procedure
4652 and then No_Return (Ent)
4654 Set_Trivial_Subprogram (Stm);
4662 -- Check for variables that are never modified
4669 -- If there is a separate spec, then transfer Never_Set_In_Source
4670 -- flags from out parameters to the corresponding entities in the
4671 -- body. The reason we do that is we want to post error flags on
4672 -- the body entities, not the spec entities.
4674 if Present (Spec_Id) then
4675 E1 := First_Entity (Spec_Id);
4676 while Present (E1) loop
4677 if Ekind (E1) = E_Out_Parameter then
4678 E2 := First_Entity (Body_Id);
4679 while Present (E2) loop
4680 exit when Chars (E1) = Chars (E2);
4684 if Present (E2) then
4685 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4693 -- Check references of the subprogram spec when we are dealing with
4694 -- an expression function due to it having a generated body.
4695 -- Otherwise, we simply check the formals of the subprogram body.
4697 if Present (Spec_Id)
4698 and then Is_Expression_Function (Spec_Id)
4700 Check_References (Spec_Id);
4702 Check_References (Body_Id);
4706 -- Check for nested subprogram, and mark outer level subprogram if so
4712 if Present (Spec_Id) then
4719 Ent := Enclosing_Subprogram (Ent);
4720 exit when No (Ent) or else Is_Subprogram (Ent);
4723 if Present (Ent) then
4724 Set_Has_Nested_Subprogram (Ent);
4728 -- Restore the limited views in the spec, if any, to let the back end
4729 -- process it without running into circularities.
4731 if Exch_Views /= No_Elist then
4732 Restore_Limited_Views (Exch_Views);
4735 if Mask_Types /= No_Elist then
4736 Unmask_Unfrozen_Types (Mask_Types);
4739 if Present (Desig_View) then
4740 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4744 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4745 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4746 end Analyze_Subprogram_Body_Helper;
4748 ------------------------------------
4749 -- Analyze_Subprogram_Declaration --
4750 ------------------------------------
4752 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4753 Scop : constant Entity_Id := Current_Scope;
4754 Designator : Entity_Id;
4756 Is_Completion : Boolean;
4757 -- Indicates whether a null procedure declaration is a completion
4760 -- Null procedures are not allowed in SPARK
4762 if Nkind (Specification (N)) = N_Procedure_Specification
4763 and then Null_Present (Specification (N))
4765 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4767 -- Null procedures are allowed in protected types, following the
4768 -- recent AI12-0147.
4770 if Is_Protected_Type (Current_Scope)
4771 and then Ada_Version < Ada_2012
4773 Error_Msg_N ("protected operation cannot be a null procedure", N);
4776 Analyze_Null_Procedure (N, Is_Completion);
4778 -- The null procedure acts as a body, nothing further is needed
4780 if Is_Completion then
4785 Designator := Analyze_Subprogram_Specification (Specification (N));
4787 -- A reference may already have been generated for the unit name, in
4788 -- which case the following call is redundant. However it is needed for
4789 -- declarations that are the rewriting of an expression function.
4791 Generate_Definition (Designator);
4793 -- Set the SPARK mode from the current context (may be overwritten later
4794 -- with explicit pragma). This is not done for entry barrier functions
4795 -- because they are generated outside the protected type and should not
4796 -- carry the mode of the enclosing context.
4798 if Nkind (N) = N_Subprogram_Declaration
4799 and then Is_Entry_Barrier_Function (N)
4804 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4805 Set_SPARK_Pragma_Inherited (Designator);
4808 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4809 -- the body of this subprogram is instantiated or inlined later and out
4810 -- of context. The body uses this attribute to restore the value of the
4813 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4814 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4817 -- Preserve relevant elaboration-related attributes of the context which
4818 -- are no longer available or very expensive to recompute once analysis,
4819 -- resolution, and expansion are over.
4821 Mark_Elaboration_Attributes
4822 (N_Id => Designator,
4826 if Debug_Flag_C then
4827 Write_Str ("==> subprogram spec ");
4828 Write_Name (Chars (Designator));
4829 Write_Str (" from ");
4830 Write_Location (Sloc (N));
4835 Validate_RCI_Subprogram_Declaration (N);
4836 New_Overloaded_Entity (Designator);
4837 Check_Delayed_Subprogram (Designator);
4839 -- If the type of the first formal of the current subprogram is a non-
4840 -- generic tagged private type, mark the subprogram as being a private
4841 -- primitive. Ditto if this is a function with controlling result, and
4842 -- the return type is currently private. In both cases, the type of the
4843 -- controlling argument or result must be in the current scope for the
4844 -- operation to be primitive.
4846 if Has_Controlling_Result (Designator)
4847 and then Is_Private_Type (Etype (Designator))
4848 and then Scope (Etype (Designator)) = Current_Scope
4849 and then not Is_Generic_Actual_Type (Etype (Designator))
4851 Set_Is_Private_Primitive (Designator);
4853 elsif Present (First_Formal (Designator)) then
4855 Formal_Typ : constant Entity_Id :=
4856 Etype (First_Formal (Designator));
4858 Set_Is_Private_Primitive (Designator,
4859 Is_Tagged_Type (Formal_Typ)
4860 and then Scope (Formal_Typ) = Current_Scope
4861 and then Is_Private_Type (Formal_Typ)
4862 and then not Is_Generic_Actual_Type (Formal_Typ));
4866 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4869 if Ada_Version >= Ada_2005
4870 and then Comes_From_Source (N)
4871 and then Is_Dispatching_Operation (Designator)
4878 if Has_Controlling_Result (Designator) then
4879 Etyp := Etype (Designator);
4882 E := First_Entity (Designator);
4884 and then Is_Formal (E)
4885 and then not Is_Controlling_Formal (E)
4893 if Is_Access_Type (Etyp) then
4894 Etyp := Directly_Designated_Type (Etyp);
4897 if Is_Interface (Etyp)
4898 and then not Is_Abstract_Subprogram (Designator)
4899 and then not (Ekind (Designator) = E_Procedure
4900 and then Null_Present (Specification (N)))
4902 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4904 -- Specialize error message based on procedures vs. functions,
4905 -- since functions can't be null subprograms.
4907 if Ekind (Designator) = E_Procedure then
4909 ("interface procedure % must be abstract or null", N);
4912 ("interface function % must be abstract", N);
4918 -- What is the following code for, it used to be
4920 -- ??? Set_Suppress_Elaboration_Checks
4921 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4923 -- The following seems equivalent, but a bit dubious
4925 if Elaboration_Checks_Suppressed (Designator) then
4926 Set_Kill_Elaboration_Checks (Designator);
4929 -- For a compilation unit, set body required. This flag will only be
4930 -- reset if a valid Import or Interface pragma is processed later on.
4932 if Nkind (Parent (N)) = N_Compilation_Unit then
4933 Set_Body_Required (Parent (N), True);
4935 if Ada_Version >= Ada_2005
4936 and then Nkind (Specification (N)) = N_Procedure_Specification
4937 and then Null_Present (Specification (N))
4940 ("null procedure cannot be declared at library level", N);
4944 Generate_Reference_To_Formals (Designator);
4945 Check_Eliminated (Designator);
4947 if Debug_Flag_C then
4949 Write_Str ("<== subprogram spec ");
4950 Write_Name (Chars (Designator));
4951 Write_Str (" from ");
4952 Write_Location (Sloc (N));
4956 -- Indicate that this is a protected operation, because it may be used
4957 -- in subsequent declarations within the protected type.
4959 if Is_Protected_Type (Current_Scope) then
4960 Set_Convention (Designator, Convention_Protected);
4963 List_Inherited_Pre_Post_Aspects (Designator);
4965 -- Process the aspects before establishing the proper categorization in
4966 -- case the subprogram is a compilation unit and one of its aspects is
4967 -- converted into a categorization pragma.
4969 if Has_Aspects (N) then
4970 Analyze_Aspect_Specifications (N, Designator);
4973 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4974 Set_Categorization_From_Scope (Designator, Scop);
4976 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4977 -- proper categorization of the unit based on its pragmas.
4980 Push_Scope (Designator);
4981 Set_Categorization_From_Pragmas (N);
4982 Validate_Categorization_Dependency (N, Designator);
4985 end Analyze_Subprogram_Declaration;
4987 --------------------------------------
4988 -- Analyze_Subprogram_Specification --
4989 --------------------------------------
4991 -- Reminder: N here really is a subprogram specification (not a subprogram
4992 -- declaration). This procedure is called to analyze the specification in
4993 -- both subprogram bodies and subprogram declarations (specs).
4995 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4996 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4997 -- Determine whether entity E denotes the spec or body of an invariant
5000 ------------------------------------
5001 -- Is_Invariant_Procedure_Or_Body --
5002 ------------------------------------
5004 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
5005 Decl : constant Node_Id := Unit_Declaration_Node (E);
5009 if Nkind (Decl) = N_Subprogram_Body then
5010 Spec := Corresponding_Spec (Decl);
5017 and then Ekind (Spec) = E_Procedure
5018 and then (Is_Partial_Invariant_Procedure (Spec)
5019 or else Is_Invariant_Procedure (Spec));
5020 end Is_Invariant_Procedure_Or_Body;
5024 Designator : constant Entity_Id := Defining_Entity (N);
5025 Formals : constant List_Id := Parameter_Specifications (N);
5027 -- Start of processing for Analyze_Subprogram_Specification
5030 -- User-defined operator is not allowed in SPARK, except as a renaming
5032 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
5033 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
5035 Check_SPARK_05_Restriction
5036 ("user-defined operator is not allowed", N);
5039 -- Proceed with analysis. Do not emit a cross-reference entry if the
5040 -- specification comes from an expression function, because it may be
5041 -- the completion of a previous declaration. If it is not, the cross-
5042 -- reference entry will be emitted for the new subprogram declaration.
5044 if Nkind (Parent (N)) /= N_Expression_Function then
5045 Generate_Definition (Designator);
5048 if Nkind (N) = N_Function_Specification then
5049 Set_Ekind (Designator, E_Function);
5050 Set_Mechanism (Designator, Default_Mechanism);
5052 Set_Ekind (Designator, E_Procedure);
5053 Set_Etype (Designator, Standard_Void_Type);
5056 -- Flag Is_Inlined_Always is True by default, and reversed to False for
5057 -- those subprograms which could be inlined in GNATprove mode (because
5058 -- Body_To_Inline is non-Empty) but should not be inlined.
5060 if GNATprove_Mode then
5061 Set_Is_Inlined_Always (Designator);
5064 -- Introduce new scope for analysis of the formals and the return type
5066 Set_Scope (Designator, Current_Scope);
5068 if Present (Formals) then
5069 Push_Scope (Designator);
5070 Process_Formals (Formals, N);
5072 -- Check dimensions in N for formals with default expression
5074 Analyze_Dimension_Formals (N, Formals);
5076 -- Ada 2005 (AI-345): If this is an overriding operation of an
5077 -- inherited interface operation, and the controlling type is
5078 -- a synchronized type, replace the type with its corresponding
5079 -- record, to match the proper signature of an overriding operation.
5080 -- Same processing for an access parameter whose designated type is
5081 -- derived from a synchronized interface.
5083 -- This modification is not done for invariant procedures because
5084 -- the corresponding record may not necessarely be visible when the
5085 -- concurrent type acts as the full view of a private type.
5088 -- type Prot is private with Type_Invariant => ...;
5089 -- procedure ConcInvariant (Obj : Prot);
5091 -- protected type Prot is ...;
5092 -- type Concurrent_Record_Prot is record ...;
5093 -- procedure ConcInvariant (Obj : Prot) is
5095 -- end ConcInvariant;
5098 -- In the example above, both the spec and body of the invariant
5099 -- procedure must utilize the private type as the controlling type.
5101 if Ada_Version >= Ada_2005
5102 and then not Is_Invariant_Procedure_Or_Body (Designator)
5106 Formal_Typ : Entity_Id;
5107 Rec_Typ : Entity_Id;
5108 Desig_Typ : Entity_Id;
5111 Formal := First_Formal (Designator);
5112 while Present (Formal) loop
5113 Formal_Typ := Etype (Formal);
5115 if Is_Concurrent_Type (Formal_Typ)
5116 and then Present (Corresponding_Record_Type (Formal_Typ))
5118 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5120 if Present (Interfaces (Rec_Typ)) then
5121 Set_Etype (Formal, Rec_Typ);
5124 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5125 Desig_Typ := Designated_Type (Formal_Typ);
5127 if Is_Concurrent_Type (Desig_Typ)
5128 and then Present (Corresponding_Record_Type (Desig_Typ))
5130 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5132 if Present (Interfaces (Rec_Typ)) then
5133 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5138 Next_Formal (Formal);
5145 -- The subprogram scope is pushed and popped around the processing of
5146 -- the return type for consistency with call above to Process_Formals
5147 -- (which itself can call Analyze_Return_Type), and to ensure that any
5148 -- itype created for the return type will be associated with the proper
5151 elsif Nkind (N) = N_Function_Specification then
5152 Push_Scope (Designator);
5153 Analyze_Return_Type (N);
5159 if Nkind (N) = N_Function_Specification then
5161 -- Deal with operator symbol case
5163 if Nkind (Designator) = N_Defining_Operator_Symbol then
5164 Valid_Operator_Definition (Designator);
5167 May_Need_Actuals (Designator);
5169 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5170 -- the subprogram is abstract also. This does not apply to renaming
5171 -- declarations, where abstractness is inherited, and to subprogram
5172 -- bodies generated for stream operations, which become renamings as
5175 -- In case of primitives associated with abstract interface types
5176 -- the check is applied later (see Analyze_Subprogram_Declaration).
5178 if not Nkind_In (Original_Node (Parent (N)),
5179 N_Abstract_Subprogram_Declaration,
5180 N_Formal_Abstract_Subprogram_Declaration,
5181 N_Subprogram_Renaming_Declaration)
5183 if Is_Abstract_Type (Etype (Designator))
5184 and then not Is_Interface (Etype (Designator))
5187 ("function that returns abstract type must be abstract", N);
5189 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5190 -- access result whose designated type is abstract.
5192 elsif Ada_Version >= Ada_2012
5193 and then Nkind (Result_Definition (N)) = N_Access_Definition
5195 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5196 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5199 ("function whose access result designates abstract type "
5200 & "must be abstract", N);
5206 end Analyze_Subprogram_Specification;
5208 -----------------------
5209 -- Check_Conformance --
5210 -----------------------
5212 procedure Check_Conformance
5213 (New_Id : Entity_Id;
5215 Ctype : Conformance_Type;
5217 Conforms : out Boolean;
5218 Err_Loc : Node_Id := Empty;
5219 Get_Inst : Boolean := False;
5220 Skip_Controlling_Formals : Boolean := False)
5222 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5223 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5224 -- If Errmsg is True, then processing continues to post an error message
5225 -- for conformance error on given node. Two messages are output. The
5226 -- first message points to the previous declaration with a general "no
5227 -- conformance" message. The second is the detailed reason, supplied as
5228 -- Msg. The parameter N provide information for a possible & insertion
5229 -- in the message, and also provides the location for posting the
5230 -- message in the absence of a specified Err_Loc location.
5232 function Conventions_Match
5234 Id2 : Entity_Id) return Boolean;
5235 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5238 -----------------------
5239 -- Conformance_Error --
5240 -----------------------
5242 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5249 if No (Err_Loc) then
5255 Error_Msg_Sloc := Sloc (Old_Id);
5258 when Type_Conformant =>
5259 Error_Msg_N -- CODEFIX
5260 ("not type conformant with declaration#!", Enode);
5262 when Mode_Conformant =>
5263 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5265 ("not mode conformant with operation inherited#!",
5269 ("not mode conformant with declaration#!", Enode);
5272 when Subtype_Conformant =>
5273 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5275 ("not subtype conformant with operation inherited#!",
5279 ("not subtype conformant with declaration#!", Enode);
5282 when Fully_Conformant =>
5283 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5284 Error_Msg_N -- CODEFIX
5285 ("not fully conformant with operation inherited#!",
5288 Error_Msg_N -- CODEFIX
5289 ("not fully conformant with declaration#!", Enode);
5293 Error_Msg_NE (Msg, Enode, N);
5295 end Conformance_Error;
5297 -----------------------
5298 -- Conventions_Match --
5299 -----------------------
5301 function Conventions_Match
5303 Id2 : Entity_Id) return Boolean
5306 -- Ignore the conventions of anonymous access-to-subprogram types
5307 -- and subprogram types because these are internally generated and
5308 -- the only way these may receive a convention is if they inherit
5309 -- the convention of a related subprogram.
5311 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5314 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5319 -- Otherwise compare the conventions directly
5322 return Convention (Id1) = Convention (Id2);
5324 end Conventions_Match;
5328 Old_Type : constant Entity_Id := Etype (Old_Id);
5329 New_Type : constant Entity_Id := Etype (New_Id);
5330 Old_Formal : Entity_Id;
5331 New_Formal : Entity_Id;
5332 Access_Types_Match : Boolean;
5333 Old_Formal_Base : Entity_Id;
5334 New_Formal_Base : Entity_Id;
5336 -- Start of processing for Check_Conformance
5341 -- We need a special case for operators, since they don't appear
5344 if Ctype = Type_Conformant then
5345 if Ekind (New_Id) = E_Operator
5346 and then Operator_Matches_Spec (New_Id, Old_Id)
5352 -- If both are functions/operators, check return types conform
5354 if Old_Type /= Standard_Void_Type
5356 New_Type /= Standard_Void_Type
5358 -- If we are checking interface conformance we omit controlling
5359 -- arguments and result, because we are only checking the conformance
5360 -- of the remaining parameters.
5362 if Has_Controlling_Result (Old_Id)
5363 and then Has_Controlling_Result (New_Id)
5364 and then Skip_Controlling_Formals
5368 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5369 if Ctype >= Subtype_Conformant
5370 and then not Predicates_Match (Old_Type, New_Type)
5373 ("\predicate of return type does not match!", New_Id);
5376 ("\return type does not match!", New_Id);
5382 -- Ada 2005 (AI-231): In case of anonymous access types check the
5383 -- null-exclusion and access-to-constant attributes match.
5385 if Ada_Version >= Ada_2005
5386 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5388 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5389 or else Is_Access_Constant (Etype (Old_Type)) /=
5390 Is_Access_Constant (Etype (New_Type)))
5392 Conformance_Error ("\return type does not match!", New_Id);
5396 -- If either is a function/operator and the other isn't, error
5398 elsif Old_Type /= Standard_Void_Type
5399 or else New_Type /= Standard_Void_Type
5401 Conformance_Error ("\functions can only match functions!", New_Id);
5405 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5406 -- If this is a renaming as body, refine error message to indicate that
5407 -- the conflict is with the original declaration. If the entity is not
5408 -- frozen, the conventions don't have to match, the one of the renamed
5409 -- entity is inherited.
5411 if Ctype >= Subtype_Conformant then
5412 if not Conventions_Match (Old_Id, New_Id) then
5413 if not Is_Frozen (New_Id) then
5416 elsif Present (Err_Loc)
5417 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5418 and then Present (Corresponding_Spec (Err_Loc))
5420 Error_Msg_Name_1 := Chars (New_Id);
5422 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5423 Conformance_Error ("\prior declaration for% has convention %!");
5426 Conformance_Error ("\calling conventions do not match!");
5431 elsif Is_Formal_Subprogram (Old_Id)
5432 or else Is_Formal_Subprogram (New_Id)
5433 or else (Is_Subprogram (New_Id)
5434 and then Present (Alias (New_Id))
5435 and then Is_Formal_Subprogram (Alias (New_Id)))
5438 ("\formal subprograms are not subtype conformant "
5439 & "(RM 6.3.1 (17/3))");
5443 -- Deal with parameters
5445 -- Note: we use the entity information, rather than going directly
5446 -- to the specification in the tree. This is not only simpler, but
5447 -- absolutely necessary for some cases of conformance tests between
5448 -- operators, where the declaration tree simply does not exist.
5450 Old_Formal := First_Formal (Old_Id);
5451 New_Formal := First_Formal (New_Id);
5452 while Present (Old_Formal) and then Present (New_Formal) loop
5453 if Is_Controlling_Formal (Old_Formal)
5454 and then Is_Controlling_Formal (New_Formal)
5455 and then Skip_Controlling_Formals
5457 -- The controlling formals will have different types when
5458 -- comparing an interface operation with its match, but both
5459 -- or neither must be access parameters.
5461 if Is_Access_Type (Etype (Old_Formal))
5463 Is_Access_Type (Etype (New_Formal))
5465 goto Skip_Controlling_Formal;
5468 ("\access parameter does not match!", New_Formal);
5472 -- Ada 2012: Mode conformance also requires that formal parameters
5473 -- be both aliased, or neither.
5475 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5476 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5478 ("\aliased parameter mismatch!", New_Formal);
5482 if Ctype = Fully_Conformant then
5484 -- Names must match. Error message is more accurate if we do
5485 -- this before checking that the types of the formals match.
5487 if Chars (Old_Formal) /= Chars (New_Formal) then
5488 Conformance_Error ("\name& does not match!", New_Formal);
5490 -- Set error posted flag on new formal as well to stop
5491 -- junk cascaded messages in some cases.
5493 Set_Error_Posted (New_Formal);
5497 -- Null exclusion must match
5499 if Null_Exclusion_Present (Parent (Old_Formal))
5501 Null_Exclusion_Present (Parent (New_Formal))
5503 -- Only give error if both come from source. This should be
5504 -- investigated some time, since it should not be needed ???
5506 if Comes_From_Source (Old_Formal)
5508 Comes_From_Source (New_Formal)
5511 ("\null exclusion for& does not match", New_Formal);
5513 -- Mark error posted on the new formal to avoid duplicated
5514 -- complaint about types not matching.
5516 Set_Error_Posted (New_Formal);
5521 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5522 -- case occurs whenever a subprogram is being renamed and one of its
5523 -- parameters imposes a null exclusion. For example:
5525 -- type T is null record;
5526 -- type Acc_T is access T;
5527 -- subtype Acc_T_Sub is Acc_T;
5529 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5530 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5533 Old_Formal_Base := Etype (Old_Formal);
5534 New_Formal_Base := Etype (New_Formal);
5537 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5538 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5541 Access_Types_Match := Ada_Version >= Ada_2005
5543 -- Ensure that this rule is only applied when New_Id is a
5544 -- renaming of Old_Id.
5546 and then Nkind (Parent (Parent (New_Id))) =
5547 N_Subprogram_Renaming_Declaration
5548 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5549 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5550 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5552 -- Now handle the allowed access-type case
5554 and then Is_Access_Type (Old_Formal_Base)
5555 and then Is_Access_Type (New_Formal_Base)
5557 -- The type kinds must match. The only exception occurs with
5558 -- multiple generics of the form:
5561 -- type F is private; type A is private;
5562 -- type F_Ptr is access F; type A_Ptr is access A;
5563 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5564 -- package F_Pack is ... package A_Pack is
5565 -- package F_Inst is
5566 -- new F_Pack (A, A_Ptr, A_P);
5568 -- When checking for conformance between the parameters of A_P
5569 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5570 -- because the compiler has transformed A_Ptr into a subtype of
5571 -- F_Ptr. We catch this case in the code below.
5573 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5575 (Is_Generic_Type (Old_Formal_Base)
5576 and then Is_Generic_Type (New_Formal_Base)
5577 and then Is_Internal (New_Formal_Base)
5578 and then Etype (Etype (New_Formal_Base)) =
5580 and then Directly_Designated_Type (Old_Formal_Base) =
5581 Directly_Designated_Type (New_Formal_Base)
5582 and then ((Is_Itype (Old_Formal_Base)
5583 and then Can_Never_Be_Null (Old_Formal_Base))
5585 (Is_Itype (New_Formal_Base)
5586 and then Can_Never_Be_Null (New_Formal_Base)));
5588 -- Types must always match. In the visible part of an instance,
5589 -- usual overloading rules for dispatching operations apply, and
5590 -- we check base types (not the actual subtypes).
5592 if In_Instance_Visible_Part
5593 and then Is_Dispatching_Operation (New_Id)
5595 if not Conforming_Types
5596 (T1 => Base_Type (Etype (Old_Formal)),
5597 T2 => Base_Type (Etype (New_Formal)),
5599 Get_Inst => Get_Inst)
5600 and then not Access_Types_Match
5602 Conformance_Error ("\type of & does not match!", New_Formal);
5606 elsif not Conforming_Types
5607 (T1 => Old_Formal_Base,
5608 T2 => New_Formal_Base,
5610 Get_Inst => Get_Inst)
5611 and then not Access_Types_Match
5613 -- Don't give error message if old type is Any_Type. This test
5614 -- avoids some cascaded errors, e.g. in case of a bad spec.
5616 if Errmsg and then Old_Formal_Base = Any_Type then
5619 if Ctype >= Subtype_Conformant
5621 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5624 ("\predicate of & does not match!", New_Formal);
5627 ("\type of & does not match!", New_Formal);
5629 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5631 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5639 -- For mode conformance, mode must match
5641 if Ctype >= Mode_Conformant then
5642 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5643 if not Ekind_In (New_Id, E_Function, E_Procedure)
5644 or else not Is_Primitive_Wrapper (New_Id)
5646 Conformance_Error ("\mode of & does not match!", New_Formal);
5650 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5652 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5654 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5657 ("\mode of & does not match!", New_Formal);
5664 -- Part of mode conformance for access types is having the same
5665 -- constant modifier.
5667 elsif Access_Types_Match
5668 and then Is_Access_Constant (Old_Formal_Base) /=
5669 Is_Access_Constant (New_Formal_Base)
5672 ("\constant modifier does not match!", New_Formal);
5677 if Ctype >= Subtype_Conformant then
5679 -- Ada 2005 (AI-231): In case of anonymous access types check
5680 -- the null-exclusion and access-to-constant attributes must
5681 -- match. For null exclusion, we test the types rather than the
5682 -- formals themselves, since the attribute is only set reliably
5683 -- on the formals in the Ada 95 case, and we exclude the case
5684 -- where Old_Formal is marked as controlling, to avoid errors
5685 -- when matching completing bodies with dispatching declarations
5686 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5688 if Ada_Version >= Ada_2005
5689 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5690 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5692 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5693 Can_Never_Be_Null (Etype (New_Formal))
5695 not Is_Controlling_Formal (Old_Formal))
5697 Is_Access_Constant (Etype (Old_Formal)) /=
5698 Is_Access_Constant (Etype (New_Formal)))
5700 -- Do not complain if error already posted on New_Formal. This
5701 -- avoids some redundant error messages.
5703 and then not Error_Posted (New_Formal)
5705 -- It is allowed to omit the null-exclusion in case of stream
5706 -- attribute subprograms. We recognize stream subprograms
5707 -- through their TSS-generated suffix.
5710 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5713 if TSS_Name /= TSS_Stream_Read
5714 and then TSS_Name /= TSS_Stream_Write
5715 and then TSS_Name /= TSS_Stream_Input
5716 and then TSS_Name /= TSS_Stream_Output
5718 -- Here we have a definite conformance error. It is worth
5719 -- special casing the error message for the case of a
5720 -- controlling formal (which excludes null).
5722 if Is_Controlling_Formal (New_Formal) then
5723 Error_Msg_Node_2 := Scope (New_Formal);
5725 ("\controlling formal & of & excludes null, "
5726 & "declaration must exclude null as well",
5729 -- Normal case (couldn't we give more detail here???)
5733 ("\type of & does not match!", New_Formal);
5742 -- Full conformance checks
5744 if Ctype = Fully_Conformant then
5746 -- We have checked already that names match
5748 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5750 -- Check default expressions for in parameters
5753 NewD : constant Boolean :=
5754 Present (Default_Value (New_Formal));
5755 OldD : constant Boolean :=
5756 Present (Default_Value (Old_Formal));
5758 if NewD or OldD then
5760 -- The old default value has been analyzed because the
5761 -- current full declaration will have frozen everything
5762 -- before. The new default value has not been analyzed,
5763 -- so analyze it now before we check for conformance.
5766 Push_Scope (New_Id);
5767 Preanalyze_Spec_Expression
5768 (Default_Value (New_Formal), Etype (New_Formal));
5772 if not (NewD and OldD)
5773 or else not Fully_Conformant_Expressions
5774 (Default_Value (Old_Formal),
5775 Default_Value (New_Formal))
5778 ("\default expression for & does not match!",
5787 -- A couple of special checks for Ada 83 mode. These checks are
5788 -- skipped if either entity is an operator in package Standard,
5789 -- or if either old or new instance is not from the source program.
5791 if Ada_Version = Ada_83
5792 and then Sloc (Old_Id) > Standard_Location
5793 and then Sloc (New_Id) > Standard_Location
5794 and then Comes_From_Source (Old_Id)
5795 and then Comes_From_Source (New_Id)
5798 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5799 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5802 -- Explicit IN must be present or absent in both cases. This
5803 -- test is required only in the full conformance case.
5805 if In_Present (Old_Param) /= In_Present (New_Param)
5806 and then Ctype = Fully_Conformant
5809 ("\(Ada 83) IN must appear in both declarations",
5814 -- Grouping (use of comma in param lists) must be the same
5815 -- This is where we catch a misconformance like:
5818 -- A : Integer; B : Integer
5820 -- which are represented identically in the tree except
5821 -- for the setting of the flags More_Ids and Prev_Ids.
5823 if More_Ids (Old_Param) /= More_Ids (New_Param)
5824 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5827 ("\grouping of & does not match!", New_Formal);
5833 -- This label is required when skipping controlling formals
5835 <<Skip_Controlling_Formal>>
5837 Next_Formal (Old_Formal);
5838 Next_Formal (New_Formal);
5841 if Present (Old_Formal) then
5842 Conformance_Error ("\too few parameters!");
5845 elsif Present (New_Formal) then
5846 Conformance_Error ("\too many parameters!", New_Formal);
5849 end Check_Conformance;
5851 -----------------------
5852 -- Check_Conventions --
5853 -----------------------
5855 procedure Check_Conventions (Typ : Entity_Id) is
5856 Ifaces_List : Elist_Id;
5858 procedure Check_Convention (Op : Entity_Id);
5859 -- Verify that the convention of inherited dispatching operation Op is
5860 -- consistent among all subprograms it overrides. In order to minimize
5861 -- the search, Search_From is utilized to designate a specific point in
5862 -- the list rather than iterating over the whole list once more.
5864 ----------------------
5865 -- Check_Convention --
5866 ----------------------
5868 procedure Check_Convention (Op : Entity_Id) is
5869 Op_Conv : constant Convention_Id := Convention (Op);
5870 Iface_Conv : Convention_Id;
5871 Iface_Elmt : Elmt_Id;
5872 Iface_Prim_Elmt : Elmt_Id;
5873 Iface_Prim : Entity_Id;
5876 Iface_Elmt := First_Elmt (Ifaces_List);
5877 while Present (Iface_Elmt) loop
5879 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5880 while Present (Iface_Prim_Elmt) loop
5881 Iface_Prim := Node (Iface_Prim_Elmt);
5882 Iface_Conv := Convention (Iface_Prim);
5884 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5885 and then Iface_Conv /= Op_Conv
5888 ("inconsistent conventions in primitive operations", Typ);
5890 Error_Msg_Name_1 := Chars (Op);
5891 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5892 Error_Msg_Sloc := Sloc (Op);
5894 if Comes_From_Source (Op) or else No (Alias (Op)) then
5895 if not Present (Overridden_Operation (Op)) then
5896 Error_Msg_N ("\\primitive % defined #", Typ);
5899 ("\\overriding operation % with "
5900 & "convention % defined #", Typ);
5903 else pragma Assert (Present (Alias (Op)));
5904 Error_Msg_Sloc := Sloc (Alias (Op));
5905 Error_Msg_N ("\\inherited operation % with "
5906 & "convention % defined #", Typ);
5909 Error_Msg_Name_1 := Chars (Op);
5910 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5911 Error_Msg_Sloc := Sloc (Iface_Prim);
5912 Error_Msg_N ("\\overridden operation % with "
5913 & "convention % defined #", Typ);
5915 -- Avoid cascading errors
5920 Next_Elmt (Iface_Prim_Elmt);
5923 Next_Elmt (Iface_Elmt);
5925 end Check_Convention;
5929 Prim_Op : Entity_Id;
5930 Prim_Op_Elmt : Elmt_Id;
5932 -- Start of processing for Check_Conventions
5935 if not Has_Interfaces (Typ) then
5939 Collect_Interfaces (Typ, Ifaces_List);
5941 -- The algorithm checks every overriding dispatching operation against
5942 -- all the corresponding overridden dispatching operations, detecting
5943 -- differences in conventions.
5945 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5946 while Present (Prim_Op_Elmt) loop
5947 Prim_Op := Node (Prim_Op_Elmt);
5949 -- A small optimization: skip the predefined dispatching operations
5950 -- since they always have the same convention.
5952 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5953 Check_Convention (Prim_Op);
5956 Next_Elmt (Prim_Op_Elmt);
5958 end Check_Conventions;
5960 ------------------------------
5961 -- Check_Delayed_Subprogram --
5962 ------------------------------
5964 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5965 procedure Possible_Freeze (T : Entity_Id);
5966 -- T is the type of either a formal parameter or of the return type. If
5967 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5968 -- itself must be delayed.
5970 ---------------------
5971 -- Possible_Freeze --
5972 ---------------------
5974 procedure Possible_Freeze (T : Entity_Id) is
5975 Scop : constant Entity_Id := Scope (Designator);
5978 -- If the subprogram appears within a package instance (which may be
5979 -- the wrapper package of a subprogram instance) the freeze node for
5980 -- that package will freeze the subprogram at the proper place, so
5981 -- do not emit a freeze node for the subprogram, given that it may
5982 -- appear in the wrong scope.
5984 if Ekind (Scop) = E_Package
5985 and then not Comes_From_Source (Scop)
5986 and then Is_Generic_Instance (Scop)
5990 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5991 Set_Has_Delayed_Freeze (Designator);
5993 elsif Is_Access_Type (T)
5994 and then Has_Delayed_Freeze (Designated_Type (T))
5995 and then not Is_Frozen (Designated_Type (T))
5997 Set_Has_Delayed_Freeze (Designator);
5999 end Possible_Freeze;
6005 -- Start of processing for Check_Delayed_Subprogram
6008 -- All subprograms, including abstract subprograms, may need a freeze
6009 -- node if some formal type or the return type needs one.
6011 Possible_Freeze (Etype (Designator));
6012 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
6014 -- Need delayed freeze if any of the formal types themselves need a
6015 -- delayed freeze and are not yet frozen.
6017 F := First_Formal (Designator);
6018 while Present (F) loop
6019 Possible_Freeze (Etype (F));
6020 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
6024 -- Mark functions that return by reference. Note that it cannot be done
6025 -- for delayed_freeze subprograms because the underlying returned type
6026 -- may not be known yet (for private types).
6028 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
6030 Typ : constant Entity_Id := Etype (Designator);
6031 Utyp : constant Entity_Id := Underlying_Type (Typ);
6034 if Is_Limited_View (Typ) then
6035 Set_Returns_By_Ref (Designator);
6037 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
6038 Set_Returns_By_Ref (Designator);
6042 end Check_Delayed_Subprogram;
6044 ------------------------------------
6045 -- Check_Discriminant_Conformance --
6046 ------------------------------------
6048 procedure Check_Discriminant_Conformance
6053 Old_Discr : Entity_Id := First_Discriminant (Prev);
6054 New_Discr : Node_Id := First (Discriminant_Specifications (N));
6055 New_Discr_Id : Entity_Id;
6056 New_Discr_Type : Entity_Id;
6058 procedure Conformance_Error (Msg : String; N : Node_Id);
6059 -- Post error message for conformance error on given node. Two messages
6060 -- are output. The first points to the previous declaration with a
6061 -- general "no conformance" message. The second is the detailed reason,
6062 -- supplied as Msg. The parameter N provide information for a possible
6063 -- & insertion in the message.
6065 -----------------------
6066 -- Conformance_Error --
6067 -----------------------
6069 procedure Conformance_Error (Msg : String; N : Node_Id) is
6071 Error_Msg_Sloc := Sloc (Prev_Loc);
6072 Error_Msg_N -- CODEFIX
6073 ("not fully conformant with declaration#!", N);
6074 Error_Msg_NE (Msg, N, N);
6075 end Conformance_Error;
6077 -- Start of processing for Check_Discriminant_Conformance
6080 while Present (Old_Discr) and then Present (New_Discr) loop
6081 New_Discr_Id := Defining_Identifier (New_Discr);
6083 -- The subtype mark of the discriminant on the full type has not
6084 -- been analyzed so we do it here. For an access discriminant a new
6087 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
6089 Access_Definition (N, Discriminant_Type (New_Discr));
6092 Analyze (Discriminant_Type (New_Discr));
6093 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6095 -- Ada 2005: if the discriminant definition carries a null
6096 -- exclusion, create an itype to check properly for consistency
6097 -- with partial declaration.
6099 if Is_Access_Type (New_Discr_Type)
6100 and then Null_Exclusion_Present (New_Discr)
6103 Create_Null_Excluding_Itype
6104 (T => New_Discr_Type,
6105 Related_Nod => New_Discr,
6106 Scope_Id => Current_Scope);
6110 if not Conforming_Types
6111 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6113 Conformance_Error ("type of & does not match!", New_Discr_Id);
6116 -- Treat the new discriminant as an occurrence of the old one,
6117 -- for navigation purposes, and fill in some semantic
6118 -- information, for completeness.
6120 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6121 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6122 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6127 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6128 Conformance_Error ("name & does not match!", New_Discr_Id);
6132 -- Default expressions must match
6135 NewD : constant Boolean :=
6136 Present (Expression (New_Discr));
6137 OldD : constant Boolean :=
6138 Present (Expression (Parent (Old_Discr)));
6141 if NewD or OldD then
6143 -- The old default value has been analyzed and expanded,
6144 -- because the current full declaration will have frozen
6145 -- everything before. The new default values have not been
6146 -- expanded, so expand now to check conformance.
6149 Preanalyze_Spec_Expression
6150 (Expression (New_Discr), New_Discr_Type);
6153 if not (NewD and OldD)
6154 or else not Fully_Conformant_Expressions
6155 (Expression (Parent (Old_Discr)),
6156 Expression (New_Discr))
6160 ("default expression for & does not match!",
6167 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6169 if Ada_Version = Ada_83 then
6171 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6174 -- Grouping (use of comma in param lists) must be the same
6175 -- This is where we catch a misconformance like:
6178 -- A : Integer; B : Integer
6180 -- which are represented identically in the tree except
6181 -- for the setting of the flags More_Ids and Prev_Ids.
6183 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6184 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6187 ("grouping of & does not match!", New_Discr_Id);
6193 Next_Discriminant (Old_Discr);
6197 if Present (Old_Discr) then
6198 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6201 elsif Present (New_Discr) then
6203 ("too many discriminants!", Defining_Identifier (New_Discr));
6206 end Check_Discriminant_Conformance;
6208 ----------------------------
6209 -- Check_Fully_Conformant --
6210 ----------------------------
6212 procedure Check_Fully_Conformant
6213 (New_Id : Entity_Id;
6215 Err_Loc : Node_Id := Empty)
6218 pragma Warnings (Off, Result);
6221 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6222 end Check_Fully_Conformant;
6224 --------------------------
6225 -- Check_Limited_Return --
6226 --------------------------
6228 procedure Check_Limited_Return
6234 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6235 -- replaced by anonymous access results. This is an incompatibility with
6236 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6237 -- controllable with special switch. ???
6239 -- A limited interface that is not immutably limited is OK
6241 if Is_Limited_Interface (R_Type)
6243 not (Is_Task_Interface (R_Type)
6244 or else Is_Protected_Interface (R_Type)
6245 or else Is_Synchronized_Interface (R_Type))
6249 elsif Is_Limited_Type (R_Type)
6250 and then not Is_Interface (R_Type)
6251 and then Comes_From_Source (N)
6252 and then not In_Instance_Body
6253 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6255 -- Error in Ada 2005
6257 if Ada_Version >= Ada_2005
6258 and then not Debug_Flag_Dot_L
6259 and then not GNAT_Mode
6262 ("(Ada 2005) cannot copy object of a limited type "
6263 & "(RM-2005 6.5(5.5/2))", Expr);
6265 if Is_Limited_View (R_Type) then
6267 ("\return by reference not permitted in Ada 2005", Expr);
6270 -- Warn in Ada 95 mode, to give folks a heads up about this
6273 -- In GNAT mode, this is just a warning, to allow it to be evilly
6274 -- turned off. Otherwise it is a real error.
6276 -- In a generic context, simplify the warning because it makes no
6277 -- sense to discuss pass-by-reference or copy.
6279 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6280 if Inside_A_Generic then
6282 ("return of limited object not permitted in Ada 2005 "
6283 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6285 elsif Is_Limited_View (R_Type) then
6287 ("return by reference not permitted in Ada 2005 "
6288 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6291 ("cannot copy object of a limited type in Ada 2005 "
6292 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6295 -- Ada 95 mode, and compatibility warnings disabled
6298 pragma Assert (Ada_Version <= Ada_95);
6299 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6300 return; -- skip continuation messages below
6303 if not Inside_A_Generic then
6305 ("\consider switching to return of access type", Expr);
6306 Explain_Limited_Type (R_Type, Expr);
6309 end Check_Limited_Return;
6311 ---------------------------
6312 -- Check_Mode_Conformant --
6313 ---------------------------
6315 procedure Check_Mode_Conformant
6316 (New_Id : Entity_Id;
6318 Err_Loc : Node_Id := Empty;
6319 Get_Inst : Boolean := False)
6322 pragma Warnings (Off, Result);
6325 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6326 end Check_Mode_Conformant;
6328 --------------------------------
6329 -- Check_Overriding_Indicator --
6330 --------------------------------
6332 procedure Check_Overriding_Indicator
6334 Overridden_Subp : Entity_Id;
6335 Is_Primitive : Boolean)
6341 -- No overriding indicator for literals
6343 if Ekind (Subp) = E_Enumeration_Literal then
6346 elsif Ekind (Subp) = E_Entry then
6347 Decl := Parent (Subp);
6349 -- No point in analyzing a malformed operator
6351 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6352 and then Error_Posted (Subp)
6357 Decl := Unit_Declaration_Node (Subp);
6360 if Nkind_In (Decl, N_Subprogram_Body,
6361 N_Subprogram_Body_Stub,
6362 N_Subprogram_Declaration,
6363 N_Abstract_Subprogram_Declaration,
6364 N_Subprogram_Renaming_Declaration)
6366 Spec := Specification (Decl);
6368 elsif Nkind (Decl) = N_Entry_Declaration then
6375 -- The overriding operation is type conformant with the overridden one,
6376 -- but the names of the formals are not required to match. If the names
6377 -- appear permuted in the overriding operation, this is a possible
6378 -- source of confusion that is worth diagnosing. Controlling formals
6379 -- often carry names that reflect the type, and it is not worthwhile
6380 -- requiring that their names match.
6382 if Present (Overridden_Subp)
6383 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6390 Form1 := First_Formal (Subp);
6391 Form2 := First_Formal (Overridden_Subp);
6393 -- If the overriding operation is a synchronized operation, skip
6394 -- the first parameter of the overridden operation, which is
6395 -- implicit in the new one. If the operation is declared in the
6396 -- body it is not primitive and all formals must match.
6398 if Is_Concurrent_Type (Scope (Subp))
6399 and then Is_Tagged_Type (Scope (Subp))
6400 and then not Has_Completion (Scope (Subp))
6402 Form2 := Next_Formal (Form2);
6405 if Present (Form1) then
6406 Form1 := Next_Formal (Form1);
6407 Form2 := Next_Formal (Form2);
6410 while Present (Form1) loop
6411 if not Is_Controlling_Formal (Form1)
6412 and then Present (Next_Formal (Form2))
6413 and then Chars (Form1) = Chars (Next_Formal (Form2))
6415 Error_Msg_Node_2 := Alias (Overridden_Subp);
6416 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6418 ("& does not match corresponding formal of&#",
6423 Next_Formal (Form1);
6424 Next_Formal (Form2);
6429 -- If there is an overridden subprogram, then check that there is no
6430 -- "not overriding" indicator, and mark the subprogram as overriding.
6431 -- This is not done if the overridden subprogram is marked as hidden,
6432 -- which can occur for the case of inherited controlled operations
6433 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6434 -- subprogram is not itself hidden. (Note: This condition could probably
6435 -- be simplified, leaving out the testing for the specific controlled
6436 -- cases, but it seems safer and clearer this way, and echoes similar
6437 -- special-case tests of this kind in other places.)
6439 if Present (Overridden_Subp)
6440 and then (not Is_Hidden (Overridden_Subp)
6442 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6445 and then Present (Alias (Overridden_Subp))
6446 and then not Is_Hidden (Alias (Overridden_Subp))))
6448 if Must_Not_Override (Spec) then
6449 Error_Msg_Sloc := Sloc (Overridden_Subp);
6451 if Ekind (Subp) = E_Entry then
6453 ("entry & overrides inherited operation #", Spec, Subp);
6456 ("subprogram & overrides inherited operation #", Spec, Subp);
6459 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6460 -- as an extension of Root_Controlled, and thus has a useless Adjust
6461 -- operation. This operation should not be inherited by other limited
6462 -- controlled types. An explicit Adjust for them is not overriding.
6464 elsif Must_Override (Spec)
6465 and then Chars (Overridden_Subp) = Name_Adjust
6466 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6467 and then Present (Alias (Overridden_Subp))
6468 and then In_Predefined_Unit (Alias (Overridden_Subp))
6471 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6472 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6474 elsif Is_Subprogram (Subp) then
6475 if Is_Init_Proc (Subp) then
6478 elsif No (Overridden_Operation (Subp)) then
6480 -- For entities generated by Derive_Subprograms the overridden
6481 -- operation is the inherited primitive (which is available
6482 -- through the attribute alias)
6484 if (Is_Dispatching_Operation (Subp)
6485 or else Is_Dispatching_Operation (Overridden_Subp))
6486 and then not Comes_From_Source (Overridden_Subp)
6487 and then Find_Dispatching_Type (Overridden_Subp) =
6488 Find_Dispatching_Type (Subp)
6489 and then Present (Alias (Overridden_Subp))
6490 and then Comes_From_Source (Alias (Overridden_Subp))
6492 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6493 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6496 Set_Overridden_Operation (Subp, Overridden_Subp);
6497 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6502 -- If primitive flag is set or this is a protected operation, then
6503 -- the operation is overriding at the point of its declaration, so
6504 -- warn if necessary. Otherwise it may have been declared before the
6505 -- operation it overrides and no check is required.
6508 and then not Must_Override (Spec)
6509 and then (Is_Primitive
6510 or else Ekind (Scope (Subp)) = E_Protected_Type)
6512 Style.Missing_Overriding (Decl, Subp);
6515 -- If Subp is an operator, it may override a predefined operation, if
6516 -- it is defined in the same scope as the type to which it applies.
6517 -- In that case Overridden_Subp is empty because of our implicit
6518 -- representation for predefined operators. We have to check whether the
6519 -- signature of Subp matches that of a predefined operator. Note that
6520 -- first argument provides the name of the operator, and the second
6521 -- argument the signature that may match that of a standard operation.
6522 -- If the indicator is overriding, then the operator must match a
6523 -- predefined signature, because we know already that there is no
6524 -- explicit overridden operation.
6526 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6527 if Must_Not_Override (Spec) then
6529 -- If this is not a primitive or a protected subprogram, then
6530 -- "not overriding" is illegal.
6533 and then Ekind (Scope (Subp)) /= E_Protected_Type
6535 Error_Msg_N ("overriding indicator only allowed "
6536 & "if subprogram is primitive", Subp);
6538 elsif Can_Override_Operator (Subp) then
6540 ("subprogram& overrides predefined operator ", Spec, Subp);
6543 elsif Must_Override (Spec) then
6544 if No (Overridden_Operation (Subp))
6545 and then not Can_Override_Operator (Subp)
6547 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6550 elsif not Error_Posted (Subp)
6551 and then Style_Check
6552 and then Can_Override_Operator (Subp)
6553 and then not In_Predefined_Unit (Subp)
6555 -- If style checks are enabled, indicate that the indicator is
6556 -- missing. However, at the point of declaration, the type of
6557 -- which this is a primitive operation may be private, in which
6558 -- case the indicator would be premature.
6560 if Has_Private_Declaration (Etype (Subp))
6561 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6565 Style.Missing_Overriding (Decl, Subp);
6569 elsif Must_Override (Spec) then
6570 if Ekind (Subp) = E_Entry then
6571 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6573 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6576 -- If the operation is marked "not overriding" and it's not primitive
6577 -- then an error is issued, unless this is an operation of a task or
6578 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6579 -- has been specified have already been checked above.
6581 elsif Must_Not_Override (Spec)
6582 and then not Is_Primitive
6583 and then Ekind (Subp) /= E_Entry
6584 and then Ekind (Scope (Subp)) /= E_Protected_Type
6587 ("overriding indicator only allowed if subprogram is primitive",
6591 end Check_Overriding_Indicator;
6597 -- Note: this procedure needs to know far too much about how the expander
6598 -- messes with exceptions. The use of the flag Exception_Junk and the
6599 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6600 -- works, but is not very clean. It would be better if the expansion
6601 -- routines would leave Original_Node working nicely, and we could use
6602 -- Original_Node here to ignore all the peculiar expander messing ???
6604 procedure Check_Returns
6608 Proc : Entity_Id := Empty)
6612 procedure Check_Statement_Sequence (L : List_Id);
6613 -- Internal recursive procedure to check a list of statements for proper
6614 -- termination by a return statement (or a transfer of control or a
6615 -- compound statement that is itself internally properly terminated).
6617 ------------------------------
6618 -- Check_Statement_Sequence --
6619 ------------------------------
6621 procedure Check_Statement_Sequence (L : List_Id) is
6626 function Assert_False return Boolean;
6627 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6628 -- rewritten as a null statement when assertions are off. The assert
6629 -- is not active, but it is still enough to kill the warning.
6635 function Assert_False return Boolean is
6636 Orig : constant Node_Id := Original_Node (Last_Stm);
6639 if Nkind (Orig) = N_Pragma
6640 and then Pragma_Name (Orig) = Name_Assert
6641 and then not Error_Posted (Orig)
6644 Arg : constant Node_Id :=
6645 First (Pragma_Argument_Associations (Orig));
6646 Exp : constant Node_Id := Expression (Arg);
6648 return Nkind (Exp) = N_Identifier
6649 and then Chars (Exp) = Name_False;
6659 Raise_Exception_Call : Boolean;
6660 -- Set True if statement sequence terminated by Raise_Exception call
6661 -- or a Reraise_Occurrence call.
6663 -- Start of processing for Check_Statement_Sequence
6666 Raise_Exception_Call := False;
6668 -- Get last real statement
6670 Last_Stm := Last (L);
6672 -- Deal with digging out exception handler statement sequences that
6673 -- have been transformed by the local raise to goto optimization.
6674 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6675 -- optimization has occurred, we are looking at something like:
6678 -- original stmts in block
6682 -- goto L1; | omitted if No_Exception_Propagation
6687 -- goto L3; -- skip handler when exception not raised
6689 -- <<L1>> -- target label for local exception
6703 -- and what we have to do is to dig out the estmts1 and estmts2
6704 -- sequences (which were the original sequences of statements in
6705 -- the exception handlers) and check them.
6707 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6712 exit when Nkind (Stm) /= N_Block_Statement;
6713 exit when not Exception_Junk (Stm);
6716 exit when Nkind (Stm) /= N_Label;
6717 exit when not Exception_Junk (Stm);
6718 Check_Statement_Sequence
6719 (Statements (Handled_Statement_Sequence (Next (Stm))));
6724 exit when Nkind (Stm) /= N_Goto_Statement;
6725 exit when not Exception_Junk (Stm);
6729 -- Don't count pragmas
6731 while Nkind (Last_Stm) = N_Pragma
6733 -- Don't count call to SS_Release (can happen after Raise_Exception)
6736 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6738 Nkind (Name (Last_Stm)) = N_Identifier
6740 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6742 -- Don't count exception junk
6745 (Nkind_In (Last_Stm, N_Goto_Statement,
6747 N_Object_Declaration)
6748 and then Exception_Junk (Last_Stm))
6749 or else Nkind (Last_Stm) in N_Push_xxx_Label
6750 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6752 -- Inserted code, such as finalization calls, is irrelevant: we only
6753 -- need to check original source.
6755 or else Is_Rewrite_Insertion (Last_Stm)
6760 -- Here we have the "real" last statement
6762 Kind := Nkind (Last_Stm);
6764 -- Transfer of control, OK. Note that in the No_Return procedure
6765 -- case, we already diagnosed any explicit return statements, so
6766 -- we can treat them as OK in this context.
6768 if Is_Transfer (Last_Stm) then
6771 -- Check cases of explicit non-indirect procedure calls
6773 elsif Kind = N_Procedure_Call_Statement
6774 and then Is_Entity_Name (Name (Last_Stm))
6776 -- Check call to Raise_Exception procedure which is treated
6777 -- specially, as is a call to Reraise_Occurrence.
6779 -- We suppress the warning in these cases since it is likely that
6780 -- the programmer really does not expect to deal with the case
6781 -- of Null_Occurrence, and thus would find a warning about a
6782 -- missing return curious, and raising Program_Error does not
6783 -- seem such a bad behavior if this does occur.
6785 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6786 -- behavior will be to raise Constraint_Error (see AI-329).
6788 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6790 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6792 Raise_Exception_Call := True;
6794 -- For Raise_Exception call, test first argument, if it is
6795 -- an attribute reference for a 'Identity call, then we know
6796 -- that the call cannot possibly return.
6799 Arg : constant Node_Id :=
6800 Original_Node (First_Actual (Last_Stm));
6802 if Nkind (Arg) = N_Attribute_Reference
6803 and then Attribute_Name (Arg) = Name_Identity
6810 -- If statement, need to look inside if there is an else and check
6811 -- each constituent statement sequence for proper termination.
6813 elsif Kind = N_If_Statement
6814 and then Present (Else_Statements (Last_Stm))
6816 Check_Statement_Sequence (Then_Statements (Last_Stm));
6817 Check_Statement_Sequence (Else_Statements (Last_Stm));
6819 if Present (Elsif_Parts (Last_Stm)) then
6821 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6824 while Present (Elsif_Part) loop
6825 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6833 -- Case statement, check each case for proper termination
6835 elsif Kind = N_Case_Statement then
6839 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6840 while Present (Case_Alt) loop
6841 Check_Statement_Sequence (Statements (Case_Alt));
6842 Next_Non_Pragma (Case_Alt);
6848 -- Block statement, check its handled sequence of statements
6850 elsif Kind = N_Block_Statement then
6856 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6865 -- Loop statement. If there is an iteration scheme, we can definitely
6866 -- fall out of the loop. Similarly if there is an exit statement, we
6867 -- can fall out. In either case we need a following return.
6869 elsif Kind = N_Loop_Statement then
6870 if Present (Iteration_Scheme (Last_Stm))
6871 or else Has_Exit (Entity (Identifier (Last_Stm)))
6875 -- A loop with no exit statement or iteration scheme is either
6876 -- an infinite loop, or it has some other exit (raise/return).
6877 -- In either case, no warning is required.
6883 -- Timed entry call, check entry call and delay alternatives
6885 -- Note: in expanded code, the timed entry call has been converted
6886 -- to a set of expanded statements on which the check will work
6887 -- correctly in any case.
6889 elsif Kind = N_Timed_Entry_Call then
6891 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6892 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6895 -- If statement sequence of entry call alternative is missing,
6896 -- then we can definitely fall through, and we post the error
6897 -- message on the entry call alternative itself.
6899 if No (Statements (ECA)) then
6902 -- If statement sequence of delay alternative is missing, then
6903 -- we can definitely fall through, and we post the error
6904 -- message on the delay alternative itself.
6906 -- Note: if both ECA and DCA are missing the return, then we
6907 -- post only one message, should be enough to fix the bugs.
6908 -- If not we will get a message next time on the DCA when the
6911 elsif No (Statements (DCA)) then
6914 -- Else check both statement sequences
6917 Check_Statement_Sequence (Statements (ECA));
6918 Check_Statement_Sequence (Statements (DCA));
6923 -- Conditional entry call, check entry call and else part
6925 -- Note: in expanded code, the conditional entry call has been
6926 -- converted to a set of expanded statements on which the check
6927 -- will work correctly in any case.
6929 elsif Kind = N_Conditional_Entry_Call then
6931 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6934 -- If statement sequence of entry call alternative is missing,
6935 -- then we can definitely fall through, and we post the error
6936 -- message on the entry call alternative itself.
6938 if No (Statements (ECA)) then
6941 -- Else check statement sequence and else part
6944 Check_Statement_Sequence (Statements (ECA));
6945 Check_Statement_Sequence (Else_Statements (Last_Stm));
6951 -- If we fall through, issue appropriate message
6955 -- Kill warning if last statement is a raise exception call,
6956 -- or a pragma Assert (False). Note that with assertions enabled,
6957 -- such a pragma has been converted into a raise exception call
6958 -- already, so the Assert_False is for the assertions off case.
6960 if not Raise_Exception_Call and then not Assert_False then
6962 -- In GNATprove mode, it is an error to have a missing return
6964 Error_Msg_Warn := SPARK_Mode /= On;
6966 -- Issue error message or warning
6969 ("RETURN statement missing following this statement<<!",
6972 ("\Program_Error ]<<!", Last_Stm);
6975 -- Note: we set Err even though we have not issued a warning
6976 -- because we still have a case of a missing return. This is
6977 -- an extremely marginal case, probably will never be noticed
6978 -- but we might as well get it right.
6982 -- Otherwise we have the case of a procedure marked No_Return
6985 if not Raise_Exception_Call then
6986 if GNATprove_Mode then
6988 ("implied return after this statement would have raised "
6989 & "Program_Error", Last_Stm);
6991 -- In normal compilation mode, do not warn on a generated call
6992 -- (e.g. in the body of a renaming as completion).
6994 elsif Comes_From_Source (Last_Stm) then
6996 ("implied return after this statement will raise "
6997 & "Program_Error??", Last_Stm);
7000 Error_Msg_Warn := SPARK_Mode /= On;
7002 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
7006 RE : constant Node_Id :=
7007 Make_Raise_Program_Error (Sloc (Last_Stm),
7008 Reason => PE_Implicit_Return);
7010 Insert_After (Last_Stm, RE);
7014 end Check_Statement_Sequence;
7016 -- Start of processing for Check_Returns
7020 Check_Statement_Sequence (Statements (HSS));
7022 if Present (Exception_Handlers (HSS)) then
7023 Handler := First_Non_Pragma (Exception_Handlers (HSS));
7024 while Present (Handler) loop
7025 Check_Statement_Sequence (Statements (Handler));
7026 Next_Non_Pragma (Handler);
7031 ----------------------------
7032 -- Check_Subprogram_Order --
7033 ----------------------------
7035 procedure Check_Subprogram_Order (N : Node_Id) is
7037 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
7038 -- This is used to check if S1 > S2 in the sense required by this test,
7039 -- for example nameab < namec, but name2 < name10.
7041 -----------------------------
7042 -- Subprogram_Name_Greater --
7043 -----------------------------
7045 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
7050 -- Deal with special case where names are identical except for a
7051 -- numerical suffix. These are handled specially, taking the numeric
7052 -- ordering from the suffix into account.
7055 while S1 (L1) in '0' .. '9' loop
7060 while S2 (L2) in '0' .. '9' loop
7064 -- If non-numeric parts non-equal, do straight compare
7066 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
7069 -- If non-numeric parts equal, compare suffixed numeric parts. Note
7070 -- that a missing suffix is treated as numeric zero in this test.
7074 while L1 < S1'Last loop
7076 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
7080 while L2 < S2'Last loop
7082 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
7087 end Subprogram_Name_Greater;
7089 -- Start of processing for Check_Subprogram_Order
7092 -- Check body in alpha order if this is option
7095 and then Style_Check_Order_Subprograms
7096 and then Nkind (N) = N_Subprogram_Body
7097 and then Comes_From_Source (N)
7098 and then In_Extended_Main_Source_Unit (N)
7102 renames Scope_Stack.Table
7103 (Scope_Stack.Last).Last_Subprogram_Name;
7105 Body_Id : constant Entity_Id :=
7106 Defining_Entity (Specification (N));
7109 Get_Decoded_Name_String (Chars (Body_Id));
7112 if Subprogram_Name_Greater
7113 (LSN.all, Name_Buffer (1 .. Name_Len))
7115 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7121 LSN := new String'(Name_Buffer (1 .. Name_Len));
7124 end Check_Subprogram_Order;
7126 ------------------------------
7127 -- Check_Subtype_Conformant --
7128 ------------------------------
7130 procedure Check_Subtype_Conformant
7131 (New_Id : Entity_Id;
7133 Err_Loc : Node_Id := Empty;
7134 Skip_Controlling_Formals : Boolean := False;
7135 Get_Inst : Boolean := False)
7138 pragma Warnings (Off, Result);
7141 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7142 Skip_Controlling_Formals => Skip_Controlling_Formals,
7143 Get_Inst => Get_Inst);
7144 end Check_Subtype_Conformant;
7146 -----------------------------------
7147 -- Check_Synchronized_Overriding --
7148 -----------------------------------
7150 procedure Check_Synchronized_Overriding
7151 (Def_Id : Entity_Id;
7152 Overridden_Subp : out Entity_Id)
7154 Ifaces_List : Elist_Id;
7158 function Matches_Prefixed_View_Profile
7159 (Prim_Params : List_Id;
7160 Iface_Params : List_Id) return Boolean;
7161 -- Determine whether a subprogram's parameter profile Prim_Params
7162 -- matches that of a potentially overridden interface subprogram
7163 -- Iface_Params. Also determine if the type of first parameter of
7164 -- Iface_Params is an implemented interface.
7166 -----------------------------------
7167 -- Matches_Prefixed_View_Profile --
7168 -----------------------------------
7170 function Matches_Prefixed_View_Profile
7171 (Prim_Params : List_Id;
7172 Iface_Params : List_Id) return Boolean
7174 function Is_Implemented
7175 (Ifaces_List : Elist_Id;
7176 Iface : Entity_Id) return Boolean;
7177 -- Determine if Iface is implemented by the current task or
7180 --------------------
7181 -- Is_Implemented --
7182 --------------------
7184 function Is_Implemented
7185 (Ifaces_List : Elist_Id;
7186 Iface : Entity_Id) return Boolean
7188 Iface_Elmt : Elmt_Id;
7191 Iface_Elmt := First_Elmt (Ifaces_List);
7192 while Present (Iface_Elmt) loop
7193 if Node (Iface_Elmt) = Iface then
7197 Next_Elmt (Iface_Elmt);
7205 Iface_Id : Entity_Id;
7206 Iface_Param : Node_Id;
7207 Iface_Typ : Entity_Id;
7208 Prim_Id : Entity_Id;
7209 Prim_Param : Node_Id;
7210 Prim_Typ : Entity_Id;
7212 -- Start of processing for Matches_Prefixed_View_Profile
7215 Iface_Param := First (Iface_Params);
7216 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7218 if Is_Access_Type (Iface_Typ) then
7219 Iface_Typ := Designated_Type (Iface_Typ);
7222 Prim_Param := First (Prim_Params);
7224 -- The first parameter of the potentially overridden subprogram must
7225 -- be an interface implemented by Prim.
7227 if not Is_Interface (Iface_Typ)
7228 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7233 -- The checks on the object parameters are done, so move on to the
7234 -- rest of the parameters.
7236 if not In_Scope then
7237 Prim_Param := Next (Prim_Param);
7240 Iface_Param := Next (Iface_Param);
7241 while Present (Iface_Param) and then Present (Prim_Param) loop
7242 Iface_Id := Defining_Identifier (Iface_Param);
7243 Iface_Typ := Find_Parameter_Type (Iface_Param);
7245 Prim_Id := Defining_Identifier (Prim_Param);
7246 Prim_Typ := Find_Parameter_Type (Prim_Param);
7248 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7249 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7250 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7252 Iface_Typ := Designated_Type (Iface_Typ);
7253 Prim_Typ := Designated_Type (Prim_Typ);
7256 -- Case of multiple interface types inside a parameter profile
7258 -- (Obj_Param : in out Iface; ...; Param : Iface)
7260 -- If the interface type is implemented, then the matching type in
7261 -- the primitive should be the implementing record type.
7263 if Ekind (Iface_Typ) = E_Record_Type
7264 and then Is_Interface (Iface_Typ)
7265 and then Is_Implemented (Ifaces_List, Iface_Typ)
7267 if Prim_Typ /= Typ then
7271 -- The two parameters must be both mode and subtype conformant
7273 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7275 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7284 -- One of the two lists contains more parameters than the other
7286 if Present (Iface_Param) or else Present (Prim_Param) then
7291 end Matches_Prefixed_View_Profile;
7293 -- Start of processing for Check_Synchronized_Overriding
7296 Overridden_Subp := Empty;
7298 -- Def_Id must be an entry or a subprogram. We should skip predefined
7299 -- primitives internally generated by the front end; however at this
7300 -- stage predefined primitives are still not fully decorated. As a
7301 -- minor optimization we skip here internally generated subprograms.
7303 if (Ekind (Def_Id) /= E_Entry
7304 and then Ekind (Def_Id) /= E_Function
7305 and then Ekind (Def_Id) /= E_Procedure)
7306 or else not Comes_From_Source (Def_Id)
7311 -- Search for the concurrent declaration since it contains the list of
7312 -- all implemented interfaces. In this case, the subprogram is declared
7313 -- within the scope of a protected or a task type.
7315 if Present (Scope (Def_Id))
7316 and then Is_Concurrent_Type (Scope (Def_Id))
7317 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7319 Typ := Scope (Def_Id);
7322 -- The enclosing scope is not a synchronized type and the subprogram
7325 elsif No (First_Formal (Def_Id)) then
7328 -- The subprogram has formals and hence it may be a primitive of a
7332 Typ := Etype (First_Formal (Def_Id));
7334 if Is_Access_Type (Typ) then
7335 Typ := Directly_Designated_Type (Typ);
7338 if Is_Concurrent_Type (Typ)
7339 and then not Is_Generic_Actual_Type (Typ)
7343 -- This case occurs when the concurrent type is declared within a
7344 -- generic unit. As a result the corresponding record has been built
7345 -- and used as the type of the first formal, we just have to retrieve
7346 -- the corresponding concurrent type.
7348 elsif Is_Concurrent_Record_Type (Typ)
7349 and then not Is_Class_Wide_Type (Typ)
7350 and then Present (Corresponding_Concurrent_Type (Typ))
7352 Typ := Corresponding_Concurrent_Type (Typ);
7360 -- There is no overriding to check if this is an inherited operation in
7361 -- a type derivation for a generic actual.
7363 Collect_Interfaces (Typ, Ifaces_List);
7365 if Is_Empty_Elmt_List (Ifaces_List) then
7369 -- Determine whether entry or subprogram Def_Id overrides a primitive
7370 -- operation that belongs to one of the interfaces in Ifaces_List.
7373 Candidate : Entity_Id := Empty;
7374 Hom : Entity_Id := Empty;
7375 Subp : Entity_Id := Empty;
7378 -- Traverse the homonym chain, looking for a potentially overridden
7379 -- subprogram that belongs to an implemented interface.
7381 Hom := Current_Entity_In_Scope (Def_Id);
7382 while Present (Hom) loop
7386 or else not Is_Overloadable (Subp)
7387 or else not Is_Primitive (Subp)
7388 or else not Is_Dispatching_Operation (Subp)
7389 or else not Present (Find_Dispatching_Type (Subp))
7390 or else not Is_Interface (Find_Dispatching_Type (Subp))
7394 -- Entries and procedures can override abstract or null interface
7397 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7398 and then Ekind (Subp) = E_Procedure
7399 and then Matches_Prefixed_View_Profile
7400 (Parameter_Specifications (Parent (Def_Id)),
7401 Parameter_Specifications (Parent (Subp)))
7405 -- For an overridden subprogram Subp, check whether the mode
7406 -- of its first parameter is correct depending on the kind of
7407 -- synchronized type.
7410 Formal : constant Node_Id := First_Formal (Candidate);
7413 -- In order for an entry or a protected procedure to
7414 -- override, the first parameter of the overridden routine
7415 -- must be of mode "out", "in out", or access-to-variable.
7417 if Ekind_In (Candidate, E_Entry, E_Procedure)
7418 and then Is_Protected_Type (Typ)
7419 and then Ekind (Formal) /= E_In_Out_Parameter
7420 and then Ekind (Formal) /= E_Out_Parameter
7421 and then Nkind (Parameter_Type (Parent (Formal))) /=
7426 -- All other cases are OK since a task entry or routine does
7427 -- not have a restriction on the mode of the first parameter
7428 -- of the overridden interface routine.
7431 Overridden_Subp := Candidate;
7436 -- Functions can override abstract interface functions
7438 elsif Ekind (Def_Id) = E_Function
7439 and then Ekind (Subp) = E_Function
7440 and then Matches_Prefixed_View_Profile
7441 (Parameter_Specifications (Parent (Def_Id)),
7442 Parameter_Specifications (Parent (Subp)))
7443 and then Etype (Def_Id) = Etype (Subp)
7447 -- If an inherited subprogram is implemented by a protected
7448 -- function, then the first parameter of the inherited
7449 -- subprogram shall be of mode in, but not an access-to-
7450 -- variable parameter (RM 9.4(11/9)).
7452 if Present (First_Formal (Subp))
7453 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7455 (not Is_Access_Type (Etype (First_Formal (Subp)))
7457 Is_Access_Constant (Etype (First_Formal (Subp))))
7459 Overridden_Subp := Subp;
7464 Hom := Homonym (Hom);
7467 -- After examining all candidates for overriding, we are left with
7468 -- the best match, which is a mode-incompatible interface routine.
7470 if In_Scope and then Present (Candidate) then
7471 Error_Msg_PT (Def_Id, Candidate);
7474 Overridden_Subp := Candidate;
7477 end Check_Synchronized_Overriding;
7479 ---------------------------
7480 -- Check_Type_Conformant --
7481 ---------------------------
7483 procedure Check_Type_Conformant
7484 (New_Id : Entity_Id;
7486 Err_Loc : Node_Id := Empty)
7489 pragma Warnings (Off, Result);
7492 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7493 end Check_Type_Conformant;
7495 ---------------------------
7496 -- Can_Override_Operator --
7497 ---------------------------
7499 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7503 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7507 Typ := Base_Type (Etype (First_Formal (Subp)));
7509 -- Check explicitly that the operation is a primitive of the type
7511 return Operator_Matches_Spec (Subp, Subp)
7512 and then not Is_Generic_Type (Typ)
7513 and then Scope (Subp) = Scope (Typ)
7514 and then not Is_Class_Wide_Type (Typ);
7516 end Can_Override_Operator;
7518 ----------------------
7519 -- Conforming_Types --
7520 ----------------------
7522 function Conforming_Types
7525 Ctype : Conformance_Type;
7526 Get_Inst : Boolean := False) return Boolean
7528 function Base_Types_Match
7530 Typ_2 : Entity_Id) return Boolean;
7531 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7532 -- in different scopes (e.g. parent and child instances), then verify
7533 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7534 -- the same subtype chain. The whole purpose of this procedure is to
7535 -- prevent spurious ambiguities in an instantiation that may arise if
7536 -- two distinct generic types are instantiated with the same actual.
7538 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7539 -- An access parameter can designate an incomplete type. If the
7540 -- incomplete type is the limited view of a type from a limited_
7541 -- with_clause, check whether the non-limited view is available.
7542 -- If it is a (non-limited) incomplete type, get the full view.
7544 function Matches_Limited_With_View
7546 Typ_2 : Entity_Id) return Boolean;
7547 -- Returns True if and only if either Typ_1 denotes a limited view of
7548 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7549 -- the limited with view of a type is used in a subprogram declaration
7550 -- and the subprogram body is in the scope of a regular with clause for
7551 -- the same unit. In such a case, the two type entities are considered
7552 -- identical for purposes of conformance checking.
7554 ----------------------
7555 -- Base_Types_Match --
7556 ----------------------
7558 function Base_Types_Match
7560 Typ_2 : Entity_Id) return Boolean
7562 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7563 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7566 if Typ_1 = Typ_2 then
7569 elsif Base_1 = Base_2 then
7571 -- The following is too permissive. A more precise test should
7572 -- check that the generic actual is an ancestor subtype of the
7575 -- See code in Find_Corresponding_Spec that applies an additional
7576 -- filter to handle accidental amiguities in instances.
7579 not Is_Generic_Actual_Type (Typ_1)
7580 or else not Is_Generic_Actual_Type (Typ_2)
7581 or else Scope (Typ_1) /= Scope (Typ_2);
7583 -- If Typ_2 is a generic actual type it is declared as the subtype of
7584 -- the actual. If that actual is itself a subtype we need to use its
7585 -- own base type to check for compatibility.
7587 elsif Ekind (Base_2) = Ekind (Typ_2)
7588 and then Base_1 = Base_Type (Base_2)
7592 elsif Ekind (Base_1) = Ekind (Typ_1)
7593 and then Base_2 = Base_Type (Base_1)
7600 end Base_Types_Match;
7602 --------------------------
7603 -- Find_Designated_Type --
7604 --------------------------
7606 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7610 Desig := Directly_Designated_Type (Typ);
7612 if Ekind (Desig) = E_Incomplete_Type then
7614 -- If regular incomplete type, get full view if available
7616 if Present (Full_View (Desig)) then
7617 Desig := Full_View (Desig);
7619 -- If limited view of a type, get non-limited view if available,
7620 -- and check again for a regular incomplete type.
7622 elsif Present (Non_Limited_View (Desig)) then
7623 Desig := Get_Full_View (Non_Limited_View (Desig));
7628 end Find_Designated_Type;
7630 -------------------------------
7631 -- Matches_Limited_With_View --
7632 -------------------------------
7634 function Matches_Limited_With_View
7636 Typ_2 : Entity_Id) return Boolean
7638 function Is_Matching_Limited_View
7640 View : Entity_Id) return Boolean;
7641 -- Determine whether non-limited view View denotes type Typ in some
7642 -- conformant fashion.
7644 ------------------------------
7645 -- Is_Matching_Limited_View --
7646 ------------------------------
7648 function Is_Matching_Limited_View
7650 View : Entity_Id) return Boolean
7652 Root_Typ : Entity_Id;
7653 Root_View : Entity_Id;
7656 -- The non-limited view directly denotes the type
7661 -- The type is a subtype of the non-limited view
7663 elsif Is_Subtype_Of (Typ, View) then
7666 -- Both the non-limited view and the type denote class-wide types
7668 elsif Is_Class_Wide_Type (Typ)
7669 and then Is_Class_Wide_Type (View)
7671 Root_Typ := Root_Type (Typ);
7672 Root_View := Root_Type (View);
7674 if Root_Typ = Root_View then
7677 -- An incomplete tagged type and its full view may receive two
7678 -- distinct class-wide types when the related package has not
7679 -- been analyzed yet.
7682 -- type T is tagged; -- CW_1
7683 -- type T is tagged null record; -- CW_2
7686 -- This is because the package lacks any semantic information
7687 -- that may eventually link both views of T. As a consequence,
7688 -- a client of the limited view of Pack will see CW_2 while a
7689 -- client of the non-limited view of Pack will see CW_1.
7691 elsif Is_Incomplete_Type (Root_Typ)
7692 and then Present (Full_View (Root_Typ))
7693 and then Full_View (Root_Typ) = Root_View
7697 elsif Is_Incomplete_Type (Root_View)
7698 and then Present (Full_View (Root_View))
7699 and then Full_View (Root_View) = Root_Typ
7706 end Is_Matching_Limited_View;
7708 -- Start of processing for Matches_Limited_With_View
7711 -- In some cases a type imported through a limited_with clause, and
7712 -- its non-limited view are both visible, for example in an anonymous
7713 -- access-to-class-wide type in a formal, or when building the body
7714 -- for a subprogram renaming after the subprogram has been frozen.
7715 -- In these cases both entities designate the same type. In addition,
7716 -- if one of them is an actual in an instance, it may be a subtype of
7717 -- the non-limited view of the other.
7719 if From_Limited_With (Typ_1)
7720 and then From_Limited_With (Typ_2)
7721 and then Available_View (Typ_1) = Available_View (Typ_2)
7725 elsif From_Limited_With (Typ_1) then
7726 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7728 elsif From_Limited_With (Typ_2) then
7729 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7734 end Matches_Limited_With_View;
7738 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7740 Type_1 : Entity_Id := T1;
7741 Type_2 : Entity_Id := T2;
7743 -- Start of processing for Conforming_Types
7746 -- The context is an instance association for a formal access-to-
7747 -- subprogram type; the formal parameter types require mapping because
7748 -- they may denote other formal parameters of the generic unit.
7751 Type_1 := Get_Instance_Of (T1);
7752 Type_2 := Get_Instance_Of (T2);
7755 -- If one of the types is a view of the other introduced by a limited
7756 -- with clause, treat these as conforming for all purposes.
7758 if Matches_Limited_With_View (T1, T2) then
7761 elsif Base_Types_Match (Type_1, Type_2) then
7762 if Ctype <= Mode_Conformant then
7767 Subtypes_Statically_Match (Type_1, Type_2)
7768 and then Dimensions_Match (Type_1, Type_2);
7771 elsif Is_Incomplete_Or_Private_Type (Type_1)
7772 and then Present (Full_View (Type_1))
7773 and then Base_Types_Match (Full_View (Type_1), Type_2)
7776 Ctype <= Mode_Conformant
7777 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7779 elsif Ekind (Type_2) = E_Incomplete_Type
7780 and then Present (Full_View (Type_2))
7781 and then Base_Types_Match (Type_1, Full_View (Type_2))
7784 Ctype <= Mode_Conformant
7785 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7787 elsif Is_Private_Type (Type_2)
7788 and then In_Instance
7789 and then Present (Full_View (Type_2))
7790 and then Base_Types_Match (Type_1, Full_View (Type_2))
7793 Ctype <= Mode_Conformant
7794 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7796 -- Another confusion between views in a nested instance with an
7797 -- actual private type whose full view is not in scope.
7799 elsif Ekind (Type_2) = E_Private_Subtype
7800 and then In_Instance
7801 and then Etype (Type_2) = Type_1
7805 -- In Ada 2012, incomplete types (including limited views) can appear
7806 -- as actuals in instantiations, where they are conformant to the
7807 -- corresponding incomplete formal.
7809 elsif Is_Incomplete_Type (Type_1)
7810 and then Is_Incomplete_Type (Type_2)
7811 and then In_Instance
7812 and then (Used_As_Generic_Actual (Type_1)
7813 or else Used_As_Generic_Actual (Type_2))
7818 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7819 -- treated recursively because they carry a signature. As far as
7820 -- conformance is concerned, convention plays no role, and either
7821 -- or both could be access to protected subprograms.
7823 Are_Anonymous_Access_To_Subprogram_Types :=
7824 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7825 E_Anonymous_Access_Protected_Subprogram_Type)
7827 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7828 E_Anonymous_Access_Protected_Subprogram_Type);
7830 -- Test anonymous access type case. For this case, static subtype
7831 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7832 -- the base types because we may have built internal subtype entities
7833 -- to handle null-excluding types (see Process_Formals).
7835 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7837 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7839 -- Ada 2005 (AI-254)
7841 or else Are_Anonymous_Access_To_Subprogram_Types
7844 Desig_1 : Entity_Id;
7845 Desig_2 : Entity_Id;
7848 -- In Ada 2005, access constant indicators must match for
7849 -- subtype conformance.
7851 if Ada_Version >= Ada_2005
7852 and then Ctype >= Subtype_Conformant
7854 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7859 Desig_1 := Find_Designated_Type (Type_1);
7860 Desig_2 := Find_Designated_Type (Type_2);
7862 -- If the context is an instance association for a formal
7863 -- access-to-subprogram type; formal access parameter designated
7864 -- types require mapping because they may denote other formal
7865 -- parameters of the generic unit.
7868 Desig_1 := Get_Instance_Of (Desig_1);
7869 Desig_2 := Get_Instance_Of (Desig_2);
7872 -- It is possible for a Class_Wide_Type to be introduced for an
7873 -- incomplete type, in which case there is a separate class_ wide
7874 -- type for the full view. The types conform if their Etypes
7875 -- conform, i.e. one may be the full view of the other. This can
7876 -- only happen in the context of an access parameter, other uses
7877 -- of an incomplete Class_Wide_Type are illegal.
7879 if Is_Class_Wide_Type (Desig_1)
7881 Is_Class_Wide_Type (Desig_2)
7885 (Etype (Base_Type (Desig_1)),
7886 Etype (Base_Type (Desig_2)), Ctype);
7888 elsif Are_Anonymous_Access_To_Subprogram_Types then
7889 if Ada_Version < Ada_2005 then
7891 Ctype = Type_Conformant
7892 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7894 -- We must check the conformance of the signatures themselves
7898 Conformant : Boolean;
7901 (Desig_1, Desig_2, Ctype, False, Conformant);
7906 -- A limited view of an actual matches the corresponding
7907 -- incomplete formal.
7909 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7910 and then From_Limited_With (Desig_2)
7911 and then Used_As_Generic_Actual (Etype (Desig_2))
7916 return Base_Type (Desig_1) = Base_Type (Desig_2)
7917 and then (Ctype = Type_Conformant
7919 Subtypes_Statically_Match (Desig_1, Desig_2));
7923 -- Otherwise definitely no match
7926 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7927 and then Is_Access_Type (Type_2))
7928 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7929 and then Is_Access_Type (Type_1)))
7932 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7934 May_Hide_Profile := True;
7939 end Conforming_Types;
7941 --------------------------
7942 -- Create_Extra_Formals --
7943 --------------------------
7945 procedure Create_Extra_Formals (E : Entity_Id) is
7946 First_Extra : Entity_Id := Empty;
7948 Last_Extra : Entity_Id := Empty;
7950 function Add_Extra_Formal
7951 (Assoc_Entity : Entity_Id;
7954 Suffix : String) return Entity_Id;
7955 -- Add an extra formal to the current list of formals and extra formals.
7956 -- The extra formal is added to the end of the list of extra formals,
7957 -- and also returned as the result. These formals are always of mode IN.
7958 -- The new formal has the type Typ, is declared in Scope, and its name
7959 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7960 -- The following suffixes are currently used. They should not be changed
7961 -- without coordinating with CodePeer, which makes use of these to
7962 -- provide better messages.
7964 -- O denotes the Constrained bit.
7965 -- L denotes the accessibility level.
7966 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7967 -- the full list in exp_ch6.BIP_Formal_Kind.
7969 ----------------------
7970 -- Add_Extra_Formal --
7971 ----------------------
7973 function Add_Extra_Formal
7974 (Assoc_Entity : Entity_Id;
7977 Suffix : String) return Entity_Id
7979 EF : constant Entity_Id :=
7980 Make_Defining_Identifier (Sloc (Assoc_Entity),
7981 Chars => New_External_Name (Chars (Assoc_Entity),
7985 -- A little optimization. Never generate an extra formal for the
7986 -- _init operand of an initialization procedure, since it could
7989 if Chars (Formal) = Name_uInit then
7993 Set_Ekind (EF, E_In_Parameter);
7994 Set_Actual_Subtype (EF, Typ);
7995 Set_Etype (EF, Typ);
7996 Set_Scope (EF, Scope);
7997 Set_Mechanism (EF, Default_Mechanism);
7998 Set_Formal_Validity (EF);
8000 if No (First_Extra) then
8002 Set_Extra_Formals (Scope, EF);
8005 if Present (Last_Extra) then
8006 Set_Extra_Formal (Last_Extra, EF);
8012 end Add_Extra_Formal;
8016 Formal_Type : Entity_Id;
8017 P_Formal : Entity_Id := Empty;
8019 -- Start of processing for Create_Extra_Formals
8022 -- We never generate extra formals if expansion is not active because we
8023 -- don't need them unless we are generating code.
8025 if not Expander_Active then
8029 -- No need to generate extra formals in interface thunks whose target
8030 -- primitive has no extra formals.
8032 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
8036 -- If this is a derived subprogram then the subtypes of the parent
8037 -- subprogram's formal parameters will be used to determine the need
8038 -- for extra formals.
8040 if Is_Overloadable (E) and then Present (Alias (E)) then
8041 P_Formal := First_Formal (Alias (E));
8044 Formal := First_Formal (E);
8045 while Present (Formal) loop
8046 Last_Extra := Formal;
8047 Next_Formal (Formal);
8050 -- If Extra_Formals were already created, don't do it again. This
8051 -- situation may arise for subprogram types created as part of
8052 -- dispatching calls (see Expand_Dispatching_Call).
8054 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
8058 -- If the subprogram is a predefined dispatching subprogram then don't
8059 -- generate any extra constrained or accessibility level formals. In
8060 -- general we suppress these for internal subprograms (by not calling
8061 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
8062 -- generated stream attributes do get passed through because extra
8063 -- build-in-place formals are needed in some cases (limited 'Input).
8065 if Is_Predefined_Internal_Operation (E) then
8066 goto Test_For_Func_Result_Extras;
8069 Formal := First_Formal (E);
8070 while Present (Formal) loop
8072 -- Create extra formal for supporting the attribute 'Constrained.
8073 -- The case of a private type view without discriminants also
8074 -- requires the extra formal if the underlying type has defaulted
8077 if Ekind (Formal) /= E_In_Parameter then
8078 if Present (P_Formal) then
8079 Formal_Type := Etype (P_Formal);
8081 Formal_Type := Etype (Formal);
8084 -- Do not produce extra formals for Unchecked_Union parameters.
8085 -- Jump directly to the end of the loop.
8087 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
8088 goto Skip_Extra_Formal_Generation;
8091 if not Has_Discriminants (Formal_Type)
8092 and then Ekind (Formal_Type) in Private_Kind
8093 and then Present (Underlying_Type (Formal_Type))
8095 Formal_Type := Underlying_Type (Formal_Type);
8098 -- Suppress the extra formal if formal's subtype is constrained or
8099 -- indefinite, or we're compiling for Ada 2012 and the underlying
8100 -- type is tagged and limited. In Ada 2012, a limited tagged type
8101 -- can have defaulted discriminants, but 'Constrained is required
8102 -- to return True, so the formal is never needed (see AI05-0214).
8103 -- Note that this ensures consistency of calling sequences for
8104 -- dispatching operations when some types in a class have defaults
8105 -- on discriminants and others do not (and requiring the extra
8106 -- formal would introduce distributed overhead).
8108 -- If the type does not have a completion yet, treat as prior to
8109 -- Ada 2012 for consistency.
8111 if Has_Discriminants (Formal_Type)
8112 and then not Is_Constrained (Formal_Type)
8113 and then Is_Definite_Subtype (Formal_Type)
8114 and then (Ada_Version < Ada_2012
8115 or else No (Underlying_Type (Formal_Type))
8117 (Is_Limited_Type (Formal_Type)
8120 (Underlying_Type (Formal_Type)))))
8122 Set_Extra_Constrained
8123 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8127 -- Create extra formal for supporting accessibility checking. This
8128 -- is done for both anonymous access formals and formals of named
8129 -- access types that are marked as controlling formals. The latter
8130 -- case can occur when Expand_Dispatching_Call creates a subprogram
8131 -- type and substitutes the types of access-to-class-wide actuals
8132 -- for the anonymous access-to-specific-type of controlling formals.
8133 -- Base_Type is applied because in cases where there is a null
8134 -- exclusion the formal may have an access subtype.
8136 -- This is suppressed if we specifically suppress accessibility
8137 -- checks at the package level for either the subprogram, or the
8138 -- package in which it resides. However, we do not suppress it
8139 -- simply if the scope has accessibility checks suppressed, since
8140 -- this could cause trouble when clients are compiled with a
8141 -- different suppression setting. The explicit checks at the
8142 -- package level are safe from this point of view.
8144 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8145 or else (Is_Controlling_Formal (Formal)
8146 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8148 (Explicit_Suppress (E, Accessibility_Check)
8150 Explicit_Suppress (Scope (E), Accessibility_Check))
8153 or else Present (Extra_Accessibility (P_Formal)))
8155 Set_Extra_Accessibility
8156 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8159 -- This label is required when skipping extra formal generation for
8160 -- Unchecked_Union parameters.
8162 <<Skip_Extra_Formal_Generation>>
8164 if Present (P_Formal) then
8165 Next_Formal (P_Formal);
8168 Next_Formal (Formal);
8171 <<Test_For_Func_Result_Extras>>
8173 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8174 -- function call is ... determined by the point of call ...".
8176 if Needs_Result_Accessibility_Level (E) then
8177 Set_Extra_Accessibility_Of_Result
8178 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8181 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8182 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8184 if Is_Build_In_Place_Function (E) then
8186 Result_Subt : constant Entity_Id := Etype (E);
8187 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8188 Formal_Typ : Entity_Id;
8189 Subp_Decl : Node_Id;
8190 Discard : Entity_Id;
8193 -- In the case of functions with unconstrained result subtypes,
8194 -- add a 4-state formal indicating whether the return object is
8195 -- allocated by the caller (1), or should be allocated by the
8196 -- callee on the secondary stack (2), in the global heap (3), or
8197 -- in a user-defined storage pool (4). For the moment we just use
8198 -- Natural for the type of this formal. Note that this formal
8199 -- isn't usually needed in the case where the result subtype is
8200 -- constrained, but it is needed when the function has a tagged
8201 -- result, because generally such functions can be called in a
8202 -- dispatching context and such calls must be handled like calls
8203 -- to a class-wide function.
8205 if Needs_BIP_Alloc_Form (E) then
8208 (E, Standard_Natural,
8209 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8211 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8212 -- use a user-defined pool. This formal is not added on
8213 -- ZFP as those targets do not support pools.
8215 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8218 (E, RTE (RE_Root_Storage_Pool_Ptr),
8219 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8223 -- In the case of functions whose result type needs finalization,
8224 -- add an extra formal which represents the finalization master.
8226 if Needs_BIP_Finalization_Master (E) then
8229 (E, RTE (RE_Finalization_Master_Ptr),
8230 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8233 -- When the result type contains tasks, add two extra formals: the
8234 -- master of the tasks to be created, and the caller's activation
8237 if Has_Task (Full_Subt) then
8240 (E, RTE (RE_Master_Id),
8241 E, BIP_Formal_Suffix (BIP_Task_Master));
8244 (E, RTE (RE_Activation_Chain_Access),
8245 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8248 -- All build-in-place functions get an extra formal that will be
8249 -- passed the address of the return object within the caller.
8252 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8254 -- Incomplete_View_From_Limited_With is needed here because
8255 -- gigi gets confused if the designated type is the full view
8256 -- coming from a limited-with'ed package. In the normal case,
8257 -- (no limited with) Incomplete_View_From_Limited_With
8258 -- returns Result_Subt.
8260 Set_Directly_Designated_Type
8261 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8262 Set_Etype (Formal_Typ, Formal_Typ);
8263 Set_Depends_On_Private
8264 (Formal_Typ, Has_Private_Component (Formal_Typ));
8265 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8266 Set_Is_Access_Constant (Formal_Typ, False);
8268 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8269 -- the designated type comes from the limited view (for back-end
8272 Set_From_Limited_With
8273 (Formal_Typ, From_Limited_With (Result_Subt));
8275 Layout_Type (Formal_Typ);
8277 -- Force the definition of the Itype in case of internal function
8278 -- calls within the same or nested scope.
8280 if Is_Subprogram_Or_Generic_Subprogram (E) then
8281 Subp_Decl := Parent (E);
8283 -- The insertion point for an Itype reference should be after
8284 -- the unit declaration node of the subprogram. An exception
8285 -- to this are inherited operations from a parent type in which
8286 -- case the derived type acts as their parent.
8288 if Nkind_In (Subp_Decl, N_Function_Specification,
8289 N_Procedure_Specification)
8291 Subp_Decl := Parent (Subp_Decl);
8294 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8299 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8303 -- If this is an instance of a generic, we need to have extra formals
8306 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8307 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8309 end Create_Extra_Formals;
8311 -----------------------------
8312 -- Enter_Overloaded_Entity --
8313 -----------------------------
8315 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8316 function Matches_Predefined_Op return Boolean;
8317 -- This returns an approximation of whether S matches a predefined
8318 -- operator, based on the operator symbol, and the parameter and result
8319 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8321 ---------------------------
8322 -- Matches_Predefined_Op --
8323 ---------------------------
8325 function Matches_Predefined_Op return Boolean is
8326 Formal_1 : constant Entity_Id := First_Formal (S);
8327 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8328 Op : constant Name_Id := Chars (S);
8329 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8330 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8335 if Present (Formal_2) then
8337 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8340 -- All but "&" and "**" have same-types parameters
8349 if Type_1 /= Type_2 then
8354 -- Check parameter and result types
8362 Is_Boolean_Type (Result_Type)
8363 and then Result_Type = Type_1;
8369 Is_Integer_Type (Result_Type)
8370 and then Result_Type = Type_1;
8378 Is_Numeric_Type (Result_Type)
8379 and then Result_Type = Type_1;
8385 Is_Boolean_Type (Result_Type)
8386 and then not Is_Limited_Type (Type_1);
8394 Is_Boolean_Type (Result_Type)
8395 and then (Is_Array_Type (Type_1)
8396 or else Is_Scalar_Type (Type_1));
8398 when Name_Op_Concat =>
8399 return Is_Array_Type (Result_Type);
8401 when Name_Op_Expon =>
8403 (Is_Integer_Type (Result_Type)
8404 or else Is_Floating_Point_Type (Result_Type))
8405 and then Result_Type = Type_1
8406 and then Type_2 = Standard_Integer;
8409 raise Program_Error;
8422 Is_Numeric_Type (Result_Type)
8423 and then Result_Type = Type_1;
8427 Is_Boolean_Type (Result_Type)
8428 and then Result_Type = Type_1;
8431 raise Program_Error;
8434 end Matches_Predefined_Op;
8438 E : Entity_Id := Current_Entity_In_Scope (S);
8439 C_E : Entity_Id := Current_Entity (S);
8441 -- Start of processing for Enter_Overloaded_Entity
8445 Set_Has_Homonym (E);
8446 Set_Has_Homonym (S);
8449 Set_Is_Immediately_Visible (S);
8450 Set_Scope (S, Current_Scope);
8452 -- Chain new entity if front of homonym in current scope, so that
8453 -- homonyms are contiguous.
8455 if Present (E) and then E /= C_E then
8456 while Homonym (C_E) /= E loop
8457 C_E := Homonym (C_E);
8460 Set_Homonym (C_E, S);
8464 Set_Current_Entity (S);
8469 if Is_Inherited_Operation (S) then
8470 Append_Inherited_Subprogram (S);
8472 Append_Entity (S, Current_Scope);
8475 Set_Public_Status (S);
8477 if Debug_Flag_E then
8478 Write_Str ("New overloaded entity chain: ");
8479 Write_Name (Chars (S));
8482 while Present (E) loop
8483 Write_Str (" "); Write_Int (Int (E));
8490 -- Generate warning for hiding
8493 and then Comes_From_Source (S)
8494 and then In_Extended_Main_Source_Unit (S)
8501 -- Warn unless genuine overloading. Do not emit warning on
8502 -- hiding predefined operators in Standard (these are either an
8503 -- (artifact of our implicit declarations, or simple noise) but
8504 -- keep warning on a operator defined on a local subtype, because
8505 -- of the real danger that different operators may be applied in
8506 -- various parts of the program.
8508 -- Note that if E and S have the same scope, there is never any
8509 -- hiding. Either the two conflict, and the program is illegal,
8510 -- or S is overriding an implicit inherited subprogram.
8512 if Scope (E) /= Scope (S)
8513 and then (not Is_Overloadable (E)
8514 or else Subtype_Conformant (E, S))
8515 and then (Is_Immediately_Visible (E)
8516 or else Is_Potentially_Use_Visible (S))
8518 if Scope (E) = Standard_Standard then
8519 if Nkind (S) = N_Defining_Operator_Symbol
8520 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8522 and then Matches_Predefined_Op
8525 ("declaration of & hides predefined operator?h?", S);
8528 -- E not immediately within Standard
8531 Error_Msg_Sloc := Sloc (E);
8532 Error_Msg_N ("declaration of & hides one #?h?", S);
8537 end Enter_Overloaded_Entity;
8539 -----------------------------
8540 -- Check_Untagged_Equality --
8541 -----------------------------
8543 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8544 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8545 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8549 -- This check applies only if we have a subprogram declaration with an
8550 -- untagged record type.
8552 if Nkind (Decl) /= N_Subprogram_Declaration
8553 or else not Is_Record_Type (Typ)
8554 or else Is_Tagged_Type (Typ)
8559 -- In Ada 2012 case, we will output errors or warnings depending on
8560 -- the setting of debug flag -gnatd.E.
8562 if Ada_Version >= Ada_2012 then
8563 Error_Msg_Warn := Debug_Flag_Dot_EE;
8565 -- In earlier versions of Ada, nothing to do unless we are warning on
8566 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8569 if not Warn_On_Ada_2012_Compatibility then
8574 -- Cases where the type has already been frozen
8576 if Is_Frozen (Typ) then
8578 -- If the type is not declared in a package, or if we are in the body
8579 -- of the package or in some other scope, the new operation is not
8580 -- primitive, and therefore legal, though suspicious. Should we
8581 -- generate a warning in this case ???
8583 if Ekind (Scope (Typ)) /= E_Package
8584 or else Scope (Typ) /= Current_Scope
8588 -- If the type is a generic actual (sub)type, the operation is not
8589 -- primitive either because the base type is declared elsewhere.
8591 elsif Is_Generic_Actual_Type (Typ) then
8594 -- Here we have a definite error of declaration after freezing
8597 if Ada_Version >= Ada_2012 then
8599 ("equality operator must be declared before type & is "
8600 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8602 -- In Ada 2012 mode with error turned to warning, output one
8603 -- more warning to warn that the equality operation may not
8604 -- compose. This is the consequence of ignoring the error.
8606 if Error_Msg_Warn then
8607 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8612 ("equality operator must be declared before type& is "
8613 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8616 -- If we are in the package body, we could just move the
8617 -- declaration to the package spec, so add a message saying that.
8619 if In_Package_Body (Scope (Typ)) then
8620 if Ada_Version >= Ada_2012 then
8622 ("\move declaration to package spec<<", Eq_Op);
8625 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8628 -- Otherwise try to find the freezing point
8631 Obj_Decl := Next (Parent (Typ));
8632 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8633 if Nkind (Obj_Decl) = N_Object_Declaration
8634 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8636 -- Freezing point, output warnings
8638 if Ada_Version >= Ada_2012 then
8640 ("type& is frozen by declaration??", Obj_Decl, Typ);
8642 ("\an equality operator cannot be declared after "
8647 ("type& is frozen by declaration (Ada 2012)?y?",
8650 ("\an equality operator cannot be declared after "
8651 & "this point (Ada 2012)?y?",
8663 -- Here if type is not frozen yet. It is illegal to have a primitive
8664 -- equality declared in the private part if the type is visible.
8666 elsif not In_Same_List (Parent (Typ), Decl)
8667 and then not Is_Limited_Type (Typ)
8669 -- Shouldn't we give an RM reference here???
8671 if Ada_Version >= Ada_2012 then
8673 ("equality operator appears too late<<", Eq_Op);
8676 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8679 -- No error detected
8684 end Check_Untagged_Equality;
8686 -----------------------------
8687 -- Find_Corresponding_Spec --
8688 -----------------------------
8690 function Find_Corresponding_Spec
8692 Post_Error : Boolean := True) return Entity_Id
8694 Spec : constant Node_Id := Specification (N);
8695 Designator : constant Entity_Id := Defining_Entity (Spec);
8699 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8700 -- Even if fully conformant, a body may depend on a generic actual when
8701 -- the spec does not, or vice versa, in which case they were distinct
8702 -- entities in the generic.
8704 -------------------------------
8705 -- Different_Generic_Profile --
8706 -------------------------------
8708 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8711 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8712 -- Check that the types of corresponding formals have the same
8713 -- generic actual if any. We have to account for subtypes of a
8714 -- generic formal, declared between a spec and a body, which may
8715 -- appear distinct in an instance but matched in the generic, and
8716 -- the subtype may be used either in the spec or the body of the
8717 -- subprogram being checked.
8719 -------------------------
8720 -- Same_Generic_Actual --
8721 -------------------------
8723 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8725 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8726 -- Predicate to check whether S1 is a subtype of S2 in the source
8729 -------------------------
8730 -- Is_Declared_Subtype --
8731 -------------------------
8733 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8735 return Comes_From_Source (Parent (S1))
8736 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8737 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8738 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8739 end Is_Declared_Subtype;
8741 -- Start of processing for Same_Generic_Actual
8744 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8745 or else Is_Declared_Subtype (T1, T2)
8746 or else Is_Declared_Subtype (T2, T1);
8747 end Same_Generic_Actual;
8749 -- Start of processing for Different_Generic_Profile
8752 if not In_Instance then
8755 elsif Ekind (E) = E_Function
8756 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8761 F1 := First_Formal (Designator);
8762 F2 := First_Formal (E);
8763 while Present (F1) loop
8764 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8773 end Different_Generic_Profile;
8775 -- Start of processing for Find_Corresponding_Spec
8778 E := Current_Entity (Designator);
8779 while Present (E) loop
8781 -- We are looking for a matching spec. It must have the same scope,
8782 -- and the same name, and either be type conformant, or be the case
8783 -- of a library procedure spec and its body (which belong to one
8784 -- another regardless of whether they are type conformant or not).
8786 if Scope (E) = Current_Scope then
8787 if Current_Scope = Standard_Standard
8788 or else (Ekind (E) = Ekind (Designator)
8789 and then Type_Conformant (E, Designator))
8791 -- Within an instantiation, we know that spec and body are
8792 -- subtype conformant, because they were subtype conformant in
8793 -- the generic. We choose the subtype-conformant entity here as
8794 -- well, to resolve spurious ambiguities in the instance that
8795 -- were not present in the generic (i.e. when two different
8796 -- types are given the same actual). If we are looking for a
8797 -- spec to match a body, full conformance is expected.
8801 -- Inherit the convention and "ghostness" of the matching
8802 -- spec to ensure proper full and subtype conformance.
8804 Set_Convention (Designator, Convention (E));
8806 -- Skip past subprogram bodies and subprogram renamings that
8807 -- may appear to have a matching spec, but that aren't fully
8808 -- conformant with it. That can occur in cases where an
8809 -- actual type causes unrelated homographs in the instance.
8811 if Nkind_In (N, N_Subprogram_Body,
8812 N_Subprogram_Renaming_Declaration)
8813 and then Present (Homonym (E))
8814 and then not Fully_Conformant (Designator, E)
8818 elsif not Subtype_Conformant (Designator, E) then
8821 elsif Different_Generic_Profile (E) then
8826 -- Ada 2012 (AI05-0165): For internally generated bodies of
8827 -- null procedures locate the internally generated spec. We
8828 -- enforce mode conformance since a tagged type may inherit
8829 -- from interfaces several null primitives which differ only
8830 -- in the mode of the formals.
8832 if not (Comes_From_Source (E))
8833 and then Is_Null_Procedure (E)
8834 and then not Mode_Conformant (Designator, E)
8838 -- For null procedures coming from source that are completions,
8839 -- analysis of the generated body will establish the link.
8841 elsif Comes_From_Source (E)
8842 and then Nkind (Spec) = N_Procedure_Specification
8843 and then Null_Present (Spec)
8847 -- Expression functions can be completions, but cannot be
8848 -- completed by an explicit body.
8850 elsif Comes_From_Source (E)
8851 and then Comes_From_Source (N)
8852 and then Nkind (N) = N_Subprogram_Body
8853 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8854 N_Expression_Function
8856 Error_Msg_Sloc := Sloc (E);
8857 Error_Msg_N ("body conflicts with expression function#", N);
8860 elsif not Has_Completion (E) then
8861 if Nkind (N) /= N_Subprogram_Body_Stub then
8862 Set_Corresponding_Spec (N, E);
8865 Set_Has_Completion (E);
8868 elsif Nkind (Parent (N)) = N_Subunit then
8870 -- If this is the proper body of a subunit, the completion
8871 -- flag is set when analyzing the stub.
8875 -- If E is an internal function with a controlling result that
8876 -- was created for an operation inherited by a null extension,
8877 -- it may be overridden by a body without a previous spec (one
8878 -- more reason why these should be shunned). In that case we
8879 -- remove the generated body if present, because the current
8880 -- one is the explicit overriding.
8882 elsif Ekind (E) = E_Function
8883 and then Ada_Version >= Ada_2005
8884 and then not Comes_From_Source (E)
8885 and then Has_Controlling_Result (E)
8886 and then Is_Null_Extension (Etype (E))
8887 and then Comes_From_Source (Spec)
8889 Set_Has_Completion (E, False);
8892 and then Nkind (Parent (E)) = N_Function_Specification
8895 (Unit_Declaration_Node
8896 (Corresponding_Body (Unit_Declaration_Node (E))));
8900 -- If expansion is disabled, or if the wrapper function has
8901 -- not been generated yet, this a late body overriding an
8902 -- inherited operation, or it is an overriding by some other
8903 -- declaration before the controlling result is frozen. In
8904 -- either case this is a declaration of a new entity.
8910 -- If the body already exists, then this is an error unless
8911 -- the previous declaration is the implicit declaration of a
8912 -- derived subprogram. It is also legal for an instance to
8913 -- contain type conformant overloadable declarations (but the
8914 -- generic declaration may not), per 8.3(26/2).
8916 elsif No (Alias (E))
8917 and then not Is_Intrinsic_Subprogram (E)
8918 and then not In_Instance
8921 Error_Msg_Sloc := Sloc (E);
8923 if Is_Imported (E) then
8925 ("body not allowed for imported subprogram & declared#",
8928 Error_Msg_NE ("duplicate body for & declared#", N, E);
8932 -- Child units cannot be overloaded, so a conformance mismatch
8933 -- between body and a previous spec is an error.
8935 elsif Is_Child_Unit (E)
8937 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8939 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8944 ("body of child unit does not match previous declaration", N);
8952 -- On exit, we know that no previous declaration of subprogram exists
8955 end Find_Corresponding_Spec;
8957 ----------------------
8958 -- Fully_Conformant --
8959 ----------------------
8961 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8964 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8966 end Fully_Conformant;
8968 ----------------------------------
8969 -- Fully_Conformant_Expressions --
8970 ----------------------------------
8972 function Fully_Conformant_Expressions
8973 (Given_E1 : Node_Id;
8974 Given_E2 : Node_Id) return Boolean
8976 E1 : constant Node_Id := Original_Node (Given_E1);
8977 E2 : constant Node_Id := Original_Node (Given_E2);
8978 -- We always test conformance on original nodes, since it is possible
8979 -- for analysis and/or expansion to make things look as though they
8980 -- conform when they do not, e.g. by converting 1+2 into 3.
8982 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8983 renames Fully_Conformant_Expressions;
8985 function FCL (L1, L2 : List_Id) return Boolean;
8986 -- Compare elements of two lists for conformance. Elements have to be
8987 -- conformant, and actuals inserted as default parameters do not match
8988 -- explicit actuals with the same value.
8990 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8991 -- Compare an operator node with a function call
8997 function FCL (L1, L2 : List_Id) return Boolean is
9001 if L1 = No_List then
9007 if L2 = No_List then
9013 -- Compare two lists, skipping rewrite insertions (we want to compare
9014 -- the original trees, not the expanded versions).
9017 if Is_Rewrite_Insertion (N1) then
9019 elsif Is_Rewrite_Insertion (N2) then
9025 elsif not FCE (N1, N2) then
9038 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
9039 Actuals : constant List_Id := Parameter_Associations (Call_Node);
9044 or else Entity (Op_Node) /= Entity (Name (Call_Node))
9049 Act := First (Actuals);
9051 if Nkind (Op_Node) in N_Binary_Op then
9052 if not FCE (Left_Opnd (Op_Node), Act) then
9059 return Present (Act)
9060 and then FCE (Right_Opnd (Op_Node), Act)
9061 and then No (Next (Act));
9065 -- Start of processing for Fully_Conformant_Expressions
9068 -- Nonconformant if paren count does not match. Note: if some idiot
9069 -- complains that we don't do this right for more than 3 levels of
9070 -- parentheses, they will be treated with the respect they deserve.
9072 if Paren_Count (E1) /= Paren_Count (E2) then
9075 -- If same entities are referenced, then they are conformant even if
9076 -- they have different forms (RM 8.3.1(19-20)).
9078 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
9079 if Present (Entity (E1)) then
9080 return Entity (E1) = Entity (E2)
9082 -- One may be a discriminant that has been replaced by the
9083 -- corresponding discriminal.
9086 (Chars (Entity (E1)) = Chars (Entity (E2))
9087 and then Ekind (Entity (E1)) = E_Discriminant
9088 and then Ekind (Entity (E2)) = E_In_Parameter)
9090 -- The discriminant of a protected type is transformed into
9091 -- a local constant and then into a parameter of a protected
9095 (Ekind (Entity (E1)) = E_Constant
9096 and then Ekind (Entity (E2)) = E_In_Parameter
9097 and then Present (Discriminal_Link (Entity (E1)))
9098 and then Discriminal_Link (Entity (E1)) =
9099 Discriminal_Link (Entity (E2)))
9101 -- AI12-050: The loop variables of quantified expressions
9102 -- match if they have the same identifier, even though they
9103 -- are different entities.
9106 (Chars (Entity (E1)) = Chars (Entity (E2))
9107 and then Ekind (Entity (E1)) = E_Loop_Parameter
9108 and then Ekind (Entity (E2)) = E_Loop_Parameter);
9110 elsif Nkind (E1) = N_Expanded_Name
9111 and then Nkind (E2) = N_Expanded_Name
9112 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9113 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9115 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9118 -- Identifiers in component associations don't always have
9119 -- entities, but their names must conform.
9121 return Nkind (E1) = N_Identifier
9122 and then Nkind (E2) = N_Identifier
9123 and then Chars (E1) = Chars (E2);
9126 elsif Nkind (E1) = N_Character_Literal
9127 and then Nkind (E2) = N_Expanded_Name
9129 return Nkind (Selector_Name (E2)) = N_Character_Literal
9130 and then Chars (E1) = Chars (Selector_Name (E2));
9132 elsif Nkind (E2) = N_Character_Literal
9133 and then Nkind (E1) = N_Expanded_Name
9135 return Nkind (Selector_Name (E1)) = N_Character_Literal
9136 and then Chars (E2) = Chars (Selector_Name (E1));
9138 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9139 return FCO (E1, E2);
9141 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9142 return FCO (E2, E1);
9144 -- Otherwise we must have the same syntactic entity
9146 elsif Nkind (E1) /= Nkind (E2) then
9149 -- At this point, we specialize by node type
9155 FCL (Expressions (E1), Expressions (E2))
9157 FCL (Component_Associations (E1),
9158 Component_Associations (E2));
9161 if Nkind (Expression (E1)) = N_Qualified_Expression
9163 Nkind (Expression (E2)) = N_Qualified_Expression
9165 return FCE (Expression (E1), Expression (E2));
9167 -- Check that the subtype marks and any constraints
9172 Indic1 : constant Node_Id := Expression (E1);
9173 Indic2 : constant Node_Id := Expression (E2);
9178 if Nkind (Indic1) /= N_Subtype_Indication then
9180 Nkind (Indic2) /= N_Subtype_Indication
9181 and then Entity (Indic1) = Entity (Indic2);
9183 elsif Nkind (Indic2) /= N_Subtype_Indication then
9185 Nkind (Indic1) /= N_Subtype_Indication
9186 and then Entity (Indic1) = Entity (Indic2);
9189 if Entity (Subtype_Mark (Indic1)) /=
9190 Entity (Subtype_Mark (Indic2))
9195 Elt1 := First (Constraints (Constraint (Indic1)));
9196 Elt2 := First (Constraints (Constraint (Indic2)));
9197 while Present (Elt1) and then Present (Elt2) loop
9198 if not FCE (Elt1, Elt2) then
9211 when N_Attribute_Reference =>
9213 Attribute_Name (E1) = Attribute_Name (E2)
9214 and then FCL (Expressions (E1), Expressions (E2));
9218 Entity (E1) = Entity (E2)
9219 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9220 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9222 when N_Membership_Test
9226 FCE (Left_Opnd (E1), Left_Opnd (E2))
9228 FCE (Right_Opnd (E1), Right_Opnd (E2));
9230 when N_Case_Expression =>
9236 if not FCE (Expression (E1), Expression (E2)) then
9240 Alt1 := First (Alternatives (E1));
9241 Alt2 := First (Alternatives (E2));
9243 if Present (Alt1) /= Present (Alt2) then
9245 elsif No (Alt1) then
9249 if not FCE (Expression (Alt1), Expression (Alt2))
9250 or else not FCL (Discrete_Choices (Alt1),
9251 Discrete_Choices (Alt2))
9262 when N_Character_Literal =>
9264 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9266 when N_Component_Association =>
9268 FCL (Choices (E1), Choices (E2))
9270 FCE (Expression (E1), Expression (E2));
9272 when N_Explicit_Dereference =>
9274 FCE (Prefix (E1), Prefix (E2));
9276 when N_Extension_Aggregate =>
9278 FCL (Expressions (E1), Expressions (E2))
9279 and then Null_Record_Present (E1) =
9280 Null_Record_Present (E2)
9281 and then FCL (Component_Associations (E1),
9282 Component_Associations (E2));
9284 when N_Function_Call =>
9286 FCE (Name (E1), Name (E2))
9288 FCL (Parameter_Associations (E1),
9289 Parameter_Associations (E2));
9291 when N_If_Expression =>
9293 FCL (Expressions (E1), Expressions (E2));
9295 when N_Indexed_Component =>
9297 FCE (Prefix (E1), Prefix (E2))
9299 FCL (Expressions (E1), Expressions (E2));
9301 when N_Integer_Literal =>
9302 return (Intval (E1) = Intval (E2));
9307 when N_Operator_Symbol =>
9309 Chars (E1) = Chars (E2);
9311 when N_Others_Choice =>
9314 when N_Parameter_Association =>
9316 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9317 and then FCE (Explicit_Actual_Parameter (E1),
9318 Explicit_Actual_Parameter (E2));
9320 when N_Qualified_Expression
9322 | N_Unchecked_Type_Conversion
9325 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9327 FCE (Expression (E1), Expression (E2));
9329 when N_Quantified_Expression =>
9330 if not FCE (Condition (E1), Condition (E2)) then
9334 if Present (Loop_Parameter_Specification (E1))
9335 and then Present (Loop_Parameter_Specification (E2))
9338 L1 : constant Node_Id :=
9339 Loop_Parameter_Specification (E1);
9340 L2 : constant Node_Id :=
9341 Loop_Parameter_Specification (E2);
9345 Reverse_Present (L1) = Reverse_Present (L2)
9347 FCE (Defining_Identifier (L1),
9348 Defining_Identifier (L2))
9350 FCE (Discrete_Subtype_Definition (L1),
9351 Discrete_Subtype_Definition (L2));
9354 elsif Present (Iterator_Specification (E1))
9355 and then Present (Iterator_Specification (E2))
9358 I1 : constant Node_Id := Iterator_Specification (E1);
9359 I2 : constant Node_Id := Iterator_Specification (E2);
9363 FCE (Defining_Identifier (I1),
9364 Defining_Identifier (I2))
9366 Of_Present (I1) = Of_Present (I2)
9368 Reverse_Present (I1) = Reverse_Present (I2)
9369 and then FCE (Name (I1), Name (I2))
9370 and then FCE (Subtype_Indication (I1),
9371 Subtype_Indication (I2));
9374 -- The quantified expressions used different specifications to
9375 -- walk their respective ranges.
9383 FCE (Low_Bound (E1), Low_Bound (E2))
9385 FCE (High_Bound (E1), High_Bound (E2));
9387 when N_Real_Literal =>
9388 return (Realval (E1) = Realval (E2));
9390 when N_Selected_Component =>
9392 FCE (Prefix (E1), Prefix (E2))
9394 FCE (Selector_Name (E1), Selector_Name (E2));
9398 FCE (Prefix (E1), Prefix (E2))
9400 FCE (Discrete_Range (E1), Discrete_Range (E2));
9402 when N_String_Literal =>
9404 S1 : constant String_Id := Strval (E1);
9405 S2 : constant String_Id := Strval (E2);
9406 L1 : constant Nat := String_Length (S1);
9407 L2 : constant Nat := String_Length (S2);
9414 for J in 1 .. L1 loop
9415 if Get_String_Char (S1, J) /=
9416 Get_String_Char (S2, J)
9428 Entity (E1) = Entity (E2)
9430 FCE (Right_Opnd (E1), Right_Opnd (E2));
9432 -- All other node types cannot appear in this context. Strictly
9433 -- we should raise a fatal internal error. Instead we just ignore
9434 -- the nodes. This means that if anyone makes a mistake in the
9435 -- expander and mucks an expression tree irretrievably, the result
9436 -- will be a failure to detect a (probably very obscure) case
9437 -- of non-conformance, which is better than bombing on some
9438 -- case where two expressions do in fact conform.
9444 end Fully_Conformant_Expressions;
9446 ----------------------------------------
9447 -- Fully_Conformant_Discrete_Subtypes --
9448 ----------------------------------------
9450 function Fully_Conformant_Discrete_Subtypes
9451 (Given_S1 : Node_Id;
9452 Given_S2 : Node_Id) return Boolean
9454 S1 : constant Node_Id := Original_Node (Given_S1);
9455 S2 : constant Node_Id := Original_Node (Given_S2);
9457 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9458 -- Special-case for a bound given by a discriminant, which in the body
9459 -- is replaced with the discriminal of the enclosing type.
9461 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9462 -- Check both bounds
9464 -----------------------
9465 -- Conforming_Bounds --
9466 -----------------------
9468 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9470 if Is_Entity_Name (B1)
9471 and then Is_Entity_Name (B2)
9472 and then Ekind (Entity (B1)) = E_Discriminant
9474 return Chars (B1) = Chars (B2);
9477 return Fully_Conformant_Expressions (B1, B2);
9479 end Conforming_Bounds;
9481 -----------------------
9482 -- Conforming_Ranges --
9483 -----------------------
9485 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9488 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9490 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9491 end Conforming_Ranges;
9493 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9496 if Nkind (S1) /= Nkind (S2) then
9499 elsif Is_Entity_Name (S1) then
9500 return Entity (S1) = Entity (S2);
9502 elsif Nkind (S1) = N_Range then
9503 return Conforming_Ranges (S1, S2);
9505 elsif Nkind (S1) = N_Subtype_Indication then
9507 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9510 (Range_Expression (Constraint (S1)),
9511 Range_Expression (Constraint (S2)));
9515 end Fully_Conformant_Discrete_Subtypes;
9517 --------------------
9518 -- Install_Entity --
9519 --------------------
9521 procedure Install_Entity (E : Entity_Id) is
9522 Prev : constant Entity_Id := Current_Entity (E);
9524 Set_Is_Immediately_Visible (E);
9525 Set_Current_Entity (E);
9526 Set_Homonym (E, Prev);
9529 ---------------------
9530 -- Install_Formals --
9531 ---------------------
9533 procedure Install_Formals (Id : Entity_Id) is
9536 F := First_Formal (Id);
9537 while Present (F) loop
9541 end Install_Formals;
9543 -----------------------------
9544 -- Is_Interface_Conformant --
9545 -----------------------------
9547 function Is_Interface_Conformant
9548 (Tagged_Type : Entity_Id;
9549 Iface_Prim : Entity_Id;
9550 Prim : Entity_Id) return Boolean
9552 -- The operation may in fact be an inherited (implicit) operation
9553 -- rather than the original interface primitive, so retrieve the
9554 -- ultimate ancestor.
9556 Iface : constant Entity_Id :=
9557 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9558 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9560 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9561 -- Return the controlling formal of Prim
9563 ------------------------
9564 -- Controlling_Formal --
9565 ------------------------
9567 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9571 E := First_Entity (Prim);
9572 while Present (E) loop
9573 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9581 end Controlling_Formal;
9585 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9586 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9588 -- Start of processing for Is_Interface_Conformant
9591 pragma Assert (Is_Subprogram (Iface_Prim)
9592 and then Is_Subprogram (Prim)
9593 and then Is_Dispatching_Operation (Iface_Prim)
9594 and then Is_Dispatching_Operation (Prim));
9596 pragma Assert (Is_Interface (Iface)
9597 or else (Present (Alias (Iface_Prim))
9600 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9602 if Prim = Iface_Prim
9603 or else not Is_Subprogram (Prim)
9604 or else Ekind (Prim) /= Ekind (Iface_Prim)
9605 or else not Is_Dispatching_Operation (Prim)
9606 or else Scope (Prim) /= Scope (Tagged_Type)
9608 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9609 or else not Primitive_Names_Match (Iface_Prim, Prim)
9613 -- The mode of the controlling formals must match
9615 elsif Present (Iface_Ctrl_F)
9616 and then Present (Prim_Ctrl_F)
9617 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9621 -- Case of a procedure, or a function whose result type matches the
9622 -- result type of the interface primitive, or a function that has no
9623 -- controlling result (I or access I).
9625 elsif Ekind (Iface_Prim) = E_Procedure
9626 or else Etype (Prim) = Etype (Iface_Prim)
9627 or else not Has_Controlling_Result (Prim)
9629 return Type_Conformant
9630 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9632 -- Case of a function returning an interface, or an access to one. Check
9633 -- that the return types correspond.
9635 elsif Implements_Interface (Typ, Iface) then
9636 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9638 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9643 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9644 Skip_Controlling_Formals => True);
9650 end Is_Interface_Conformant;
9652 ---------------------------------
9653 -- Is_Non_Overriding_Operation --
9654 ---------------------------------
9656 function Is_Non_Overriding_Operation
9657 (Prev_E : Entity_Id;
9658 New_E : Entity_Id) return Boolean
9662 G_Typ : Entity_Id := Empty;
9664 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9665 -- If F_Type is a derived type associated with a generic actual subtype,
9666 -- then return its Generic_Parent_Type attribute, else return Empty.
9668 function Types_Correspond
9669 (P_Type : Entity_Id;
9670 N_Type : Entity_Id) return Boolean;
9671 -- Returns true if and only if the types (or designated types in the
9672 -- case of anonymous access types) are the same or N_Type is derived
9673 -- directly or indirectly from P_Type.
9675 -----------------------------
9676 -- Get_Generic_Parent_Type --
9677 -----------------------------
9679 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9685 if Is_Derived_Type (F_Typ)
9686 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9688 -- The tree must be traversed to determine the parent subtype in
9689 -- the generic unit, which unfortunately isn't always available
9690 -- via semantic attributes. ??? (Note: The use of Original_Node
9691 -- is needed for cases where a full derived type has been
9694 -- If the parent type is a scalar type, the derivation creates
9695 -- an anonymous base type for it, and the source type is its
9698 if Is_Scalar_Type (F_Typ)
9699 and then not Comes_From_Source (F_Typ)
9703 (Original_Node (Parent (First_Subtype (F_Typ))));
9705 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9707 if Nkind (Defn) = N_Derived_Type_Definition then
9708 Indic := Subtype_Indication (Defn);
9710 if Nkind (Indic) = N_Subtype_Indication then
9711 G_Typ := Entity (Subtype_Mark (Indic));
9713 G_Typ := Entity (Indic);
9716 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9717 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9719 return Generic_Parent_Type (Parent (G_Typ));
9725 end Get_Generic_Parent_Type;
9727 ----------------------
9728 -- Types_Correspond --
9729 ----------------------
9731 function Types_Correspond
9732 (P_Type : Entity_Id;
9733 N_Type : Entity_Id) return Boolean
9735 Prev_Type : Entity_Id := Base_Type (P_Type);
9736 New_Type : Entity_Id := Base_Type (N_Type);
9739 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9740 Prev_Type := Designated_Type (Prev_Type);
9743 if Ekind (New_Type) = E_Anonymous_Access_Type then
9744 New_Type := Designated_Type (New_Type);
9747 if Prev_Type = New_Type then
9750 elsif not Is_Class_Wide_Type (New_Type) then
9751 while Etype (New_Type) /= New_Type loop
9752 New_Type := Etype (New_Type);
9754 if New_Type = Prev_Type then
9760 end Types_Correspond;
9762 -- Start of processing for Is_Non_Overriding_Operation
9765 -- In the case where both operations are implicit derived subprograms
9766 -- then neither overrides the other. This can only occur in certain
9767 -- obscure cases (e.g., derivation from homographs created in a generic
9770 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9773 elsif Ekind (Current_Scope) = E_Package
9774 and then Is_Generic_Instance (Current_Scope)
9775 and then In_Private_Part (Current_Scope)
9776 and then Comes_From_Source (New_E)
9778 -- We examine the formals and result type of the inherited operation,
9779 -- to determine whether their type is derived from (the instance of)
9780 -- a generic type. The first such formal or result type is the one
9783 Formal := First_Formal (Prev_E);
9785 while Present (Formal) loop
9786 F_Typ := Base_Type (Etype (Formal));
9788 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9789 F_Typ := Designated_Type (F_Typ);
9792 G_Typ := Get_Generic_Parent_Type (F_Typ);
9793 exit when Present (G_Typ);
9795 Next_Formal (Formal);
9798 -- If the function dispatches on result check the result type
9800 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9801 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9808 -- If the generic type is a private type, then the original operation
9809 -- was not overriding in the generic, because there was no primitive
9810 -- operation to override.
9812 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9813 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9814 N_Formal_Private_Type_Definition
9818 -- The generic parent type is the ancestor of a formal derived
9819 -- type declaration. We need to check whether it has a primitive
9820 -- operation that should be overridden by New_E in the generic.
9824 P_Formal : Entity_Id;
9825 N_Formal : Entity_Id;
9829 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9832 while Present (Prim_Elt) loop
9833 P_Prim := Node (Prim_Elt);
9835 if Chars (P_Prim) = Chars (New_E)
9836 and then Ekind (P_Prim) = Ekind (New_E)
9838 P_Formal := First_Formal (P_Prim);
9839 N_Formal := First_Formal (New_E);
9840 while Present (P_Formal) and then Present (N_Formal) loop
9841 P_Typ := Etype (P_Formal);
9842 N_Typ := Etype (N_Formal);
9844 if not Types_Correspond (P_Typ, N_Typ) then
9848 Next_Entity (P_Formal);
9849 Next_Entity (N_Formal);
9852 -- Found a matching primitive operation belonging to the
9853 -- formal ancestor type, so the new subprogram is
9857 and then No (N_Formal)
9858 and then (Ekind (New_E) /= E_Function
9861 (Etype (P_Prim), Etype (New_E)))
9867 Next_Elmt (Prim_Elt);
9870 -- If no match found, then the new subprogram does not override
9871 -- in the generic (nor in the instance).
9873 -- If the type in question is not abstract, and the subprogram
9874 -- is, this will be an error if the new operation is in the
9875 -- private part of the instance. Emit a warning now, which will
9876 -- make the subsequent error message easier to understand.
9878 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9879 and then Is_Abstract_Subprogram (Prev_E)
9880 and then In_Private_Part (Current_Scope)
9882 Error_Msg_Node_2 := F_Typ;
9884 ("private operation& in generic unit does not override "
9885 & "any primitive operation of& (RM 12.3 (18))??",
9895 end Is_Non_Overriding_Operation;
9897 -------------------------------------
9898 -- List_Inherited_Pre_Post_Aspects --
9899 -------------------------------------
9901 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9903 if Opt.List_Inherited_Aspects
9904 and then Is_Subprogram_Or_Generic_Subprogram (E)
9907 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9912 for Index in Subps'Range loop
9913 Items := Contract (Subps (Index));
9915 if Present (Items) then
9916 Prag := Pre_Post_Conditions (Items);
9917 while Present (Prag) loop
9918 Error_Msg_Sloc := Sloc (Prag);
9920 if Class_Present (Prag)
9921 and then not Split_PPC (Prag)
9923 if Pragma_Name (Prag) = Name_Precondition then
9925 ("info: & inherits `Pre''Class` aspect from "
9929 ("info: & inherits `Post''Class` aspect from "
9934 Prag := Next_Pragma (Prag);
9940 end List_Inherited_Pre_Post_Aspects;
9942 ------------------------------
9943 -- Make_Inequality_Operator --
9944 ------------------------------
9946 -- S is the defining identifier of an equality operator. We build a
9947 -- subprogram declaration with the right signature. This operation is
9948 -- intrinsic, because it is always expanded as the negation of the
9949 -- call to the equality function.
9951 procedure Make_Inequality_Operator (S : Entity_Id) is
9952 Loc : constant Source_Ptr := Sloc (S);
9955 Op_Name : Entity_Id;
9957 FF : constant Entity_Id := First_Formal (S);
9958 NF : constant Entity_Id := Next_Formal (FF);
9961 -- Check that equality was properly defined, ignore call if not
9968 A : constant Entity_Id :=
9969 Make_Defining_Identifier (Sloc (FF),
9970 Chars => Chars (FF));
9972 B : constant Entity_Id :=
9973 Make_Defining_Identifier (Sloc (NF),
9974 Chars => Chars (NF));
9977 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9979 Formals := New_List (
9980 Make_Parameter_Specification (Loc,
9981 Defining_Identifier => A,
9983 New_Occurrence_Of (Etype (First_Formal (S)),
9984 Sloc (Etype (First_Formal (S))))),
9986 Make_Parameter_Specification (Loc,
9987 Defining_Identifier => B,
9989 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9990 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9993 Make_Subprogram_Declaration (Loc,
9995 Make_Function_Specification (Loc,
9996 Defining_Unit_Name => Op_Name,
9997 Parameter_Specifications => Formals,
9998 Result_Definition =>
9999 New_Occurrence_Of (Standard_Boolean, Loc)));
10001 -- Insert inequality right after equality if it is explicit or after
10002 -- the derived type when implicit. These entities are created only
10003 -- for visibility purposes, and eventually replaced in the course
10004 -- of expansion, so they do not need to be attached to the tree and
10005 -- seen by the back-end. Keeping them internal also avoids spurious
10006 -- freezing problems. The declaration is inserted in the tree for
10007 -- analysis, and removed afterwards. If the equality operator comes
10008 -- from an explicit declaration, attach the inequality immediately
10009 -- after. Else the equality is inherited from a derived type
10010 -- declaration, so insert inequality after that declaration.
10012 if No (Alias (S)) then
10013 Insert_After (Unit_Declaration_Node (S), Decl);
10014 elsif Is_List_Member (Parent (S)) then
10015 Insert_After (Parent (S), Decl);
10017 Insert_After (Parent (Etype (First_Formal (S))), Decl);
10020 Mark_Rewrite_Insertion (Decl);
10021 Set_Is_Intrinsic_Subprogram (Op_Name);
10024 Set_Has_Completion (Op_Name);
10025 Set_Corresponding_Equality (Op_Name, S);
10026 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
10028 end Make_Inequality_Operator;
10030 ----------------------
10031 -- May_Need_Actuals --
10032 ----------------------
10034 procedure May_Need_Actuals (Fun : Entity_Id) is
10039 F := First_Formal (Fun);
10041 while Present (F) loop
10042 if No (Default_Value (F)) then
10050 Set_Needs_No_Actuals (Fun, B);
10051 end May_Need_Actuals;
10053 ---------------------
10054 -- Mode_Conformant --
10055 ---------------------
10057 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
10060 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
10062 end Mode_Conformant;
10064 ---------------------------
10065 -- New_Overloaded_Entity --
10066 ---------------------------
10068 procedure New_Overloaded_Entity
10070 Derived_Type : Entity_Id := Empty)
10072 Overridden_Subp : Entity_Id := Empty;
10073 -- Set if the current scope has an operation that is type-conformant
10074 -- with S, and becomes hidden by S.
10076 Is_Primitive_Subp : Boolean;
10077 -- Set to True if the new subprogram is primitive
10080 -- Entity that S overrides
10082 procedure Check_For_Primitive_Subprogram
10083 (Is_Primitive : out Boolean;
10084 Is_Overriding : Boolean := False);
10085 -- If the subprogram being analyzed is a primitive operation of the type
10086 -- of a formal or result, set the Has_Primitive_Operations flag on the
10087 -- type, and set Is_Primitive to True (otherwise set to False). Set the
10088 -- corresponding flag on the entity itself for later use.
10090 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10091 -- True if a) E is a subprogram whose first formal is a concurrent type
10092 -- defined in the scope of E that has some entry or subprogram whose
10093 -- profile matches E, or b) E is an internally built dispatching
10094 -- subprogram of a protected type and there is a matching subprogram
10095 -- defined in the enclosing scope of the protected type, or c) E is
10096 -- an entry of a synchronized type and a matching procedure has been
10097 -- previously defined in the enclosing scope of the synchronized type.
10099 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10100 -- Check that E is declared in the private part of the current package,
10101 -- or in the package body, where it may hide a previous declaration.
10102 -- We can't use In_Private_Part by itself because this flag is also
10103 -- set when freezing entities, so we must examine the place of the
10104 -- declaration in the tree, and recognize wrapper packages as well.
10106 function Is_Overriding_Alias
10107 (Old_E : Entity_Id;
10108 New_E : Entity_Id) return Boolean;
10109 -- Check whether new subprogram and old subprogram are both inherited
10110 -- from subprograms that have distinct dispatch table entries. This can
10111 -- occur with derivations from instances with accidental homonyms. The
10112 -- function is conservative given that the converse is only true within
10113 -- instances that contain accidental overloadings.
10115 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10116 -- Report conflict between entities S and E
10118 ------------------------------------
10119 -- Check_For_Primitive_Subprogram --
10120 ------------------------------------
10122 procedure Check_For_Primitive_Subprogram
10123 (Is_Primitive : out Boolean;
10124 Is_Overriding : Boolean := False)
10126 Formal : Entity_Id;
10130 function Visible_Part_Type (T : Entity_Id) return Boolean;
10131 -- Returns true if T is declared in the visible part of the current
10132 -- package scope; otherwise returns false. Assumes that T is declared
10135 procedure Check_Private_Overriding (T : Entity_Id);
10136 -- Checks that if a primitive abstract subprogram of a visible
10137 -- abstract type is declared in a private part, then it must override
10138 -- an abstract subprogram declared in the visible part. Also checks
10139 -- that if a primitive function with a controlling result is declared
10140 -- in a private part, then it must override a function declared in
10141 -- the visible part.
10143 ------------------------------
10144 -- Check_Private_Overriding --
10145 ------------------------------
10147 procedure Check_Private_Overriding (T : Entity_Id) is
10148 function Overrides_Private_Part_Op return Boolean;
10149 -- This detects the special case where the overriding subprogram
10150 -- is overriding a subprogram that was declared in the same
10151 -- private part. That case is illegal by 3.9.3(10).
10153 function Overrides_Visible_Function
10154 (Partial_View : Entity_Id) return Boolean;
10155 -- True if S overrides a function in the visible part. The
10156 -- overridden function could be explicitly or implicitly declared.
10158 -------------------------------
10159 -- Overrides_Private_Part_Op --
10160 -------------------------------
10162 function Overrides_Private_Part_Op return Boolean is
10163 Over_Decl : constant Node_Id :=
10164 Unit_Declaration_Node (Overridden_Operation (S));
10165 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10168 pragma Assert (Is_Overriding);
10170 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10172 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10174 return In_Same_List (Over_Decl, Subp_Decl);
10175 end Overrides_Private_Part_Op;
10177 --------------------------------
10178 -- Overrides_Visible_Function --
10179 --------------------------------
10181 function Overrides_Visible_Function
10182 (Partial_View : Entity_Id) return Boolean
10185 if not Is_Overriding or else not Has_Homonym (S) then
10189 if not Present (Partial_View) then
10193 -- Search through all the homonyms H of S in the current
10194 -- package spec, and return True if we find one that matches.
10195 -- Note that Parent (H) will be the declaration of the
10196 -- partial view of T for a match.
10199 H : Entity_Id := S;
10203 exit when not Present (H) or else Scope (H) /= Scope (S);
10207 N_Private_Extension_Declaration,
10208 N_Private_Type_Declaration)
10209 and then Defining_Identifier (Parent (H)) = Partial_View
10217 end Overrides_Visible_Function;
10219 -- Start of processing for Check_Private_Overriding
10222 if Is_Package_Or_Generic_Package (Current_Scope)
10223 and then In_Private_Part (Current_Scope)
10224 and then Visible_Part_Type (T)
10225 and then not In_Instance
10227 if Is_Abstract_Type (T)
10228 and then Is_Abstract_Subprogram (S)
10229 and then (not Is_Overriding
10230 or else not Is_Abstract_Subprogram (E)
10231 or else Overrides_Private_Part_Op)
10234 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10237 elsif Ekind (S) = E_Function then
10239 Partial_View : constant Entity_Id :=
10240 Incomplete_Or_Partial_View (T);
10243 if not Overrides_Visible_Function (Partial_View) then
10245 -- Here, S is "function ... return T;" declared in
10246 -- the private part, not overriding some visible
10247 -- operation. That's illegal in the tagged case
10248 -- (but not if the private type is untagged).
10250 if ((Present (Partial_View)
10251 and then Is_Tagged_Type (Partial_View))
10252 or else (not Present (Partial_View)
10253 and then Is_Tagged_Type (T)))
10254 and then T = Base_Type (Etype (S))
10257 ("private function with tagged result must"
10258 & " override visible-part function", S);
10260 ("\move subprogram to the visible part"
10261 & " (RM 3.9.3(10))", S);
10263 -- AI05-0073: extend this test to the case of a
10264 -- function with a controlling access result.
10266 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10267 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10269 not Is_Class_Wide_Type
10270 (Designated_Type (Etype (S)))
10271 and then Ada_Version >= Ada_2012
10274 ("private function with controlling access "
10275 & "result must override visible-part function",
10278 ("\move subprogram to the visible part"
10279 & " (RM 3.9.3(10))", S);
10285 end Check_Private_Overriding;
10287 -----------------------
10288 -- Visible_Part_Type --
10289 -----------------------
10291 function Visible_Part_Type (T : Entity_Id) return Boolean is
10292 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10295 -- If the entity is a private type, then it must be declared in a
10298 if Ekind (T) in Private_Kind then
10301 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10304 elsif Is_List_Member (Declaration_Node (T))
10305 and then List_Containing (Declaration_Node (T)) =
10306 Visible_Declarations (Specification (P))
10313 end Visible_Part_Type;
10315 -- Start of processing for Check_For_Primitive_Subprogram
10318 Is_Primitive := False;
10320 if not Comes_From_Source (S) then
10323 -- If subprogram is at library level, it is not primitive operation
10325 elsif Current_Scope = Standard_Standard then
10328 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10329 and then not In_Package_Body (Current_Scope))
10330 or else Is_Overriding
10332 -- For function, check return type
10334 if Ekind (S) = E_Function then
10335 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10336 F_Typ := Designated_Type (Etype (S));
10338 F_Typ := Etype (S);
10341 B_Typ := Base_Type (F_Typ);
10343 if Scope (B_Typ) = Current_Scope
10344 and then not Is_Class_Wide_Type (B_Typ)
10345 and then not Is_Generic_Type (B_Typ)
10347 Is_Primitive := True;
10348 Set_Has_Primitive_Operations (B_Typ);
10349 Set_Is_Primitive (S);
10350 Check_Private_Overriding (B_Typ);
10352 -- The Ghost policy in effect at the point of declaration
10353 -- or a tagged type and a primitive operation must match
10354 -- (SPARK RM 6.9(16)).
10356 Check_Ghost_Primitive (S, B_Typ);
10360 -- For all subprograms, check formals
10362 Formal := First_Formal (S);
10363 while Present (Formal) loop
10364 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10365 F_Typ := Designated_Type (Etype (Formal));
10367 F_Typ := Etype (Formal);
10370 B_Typ := Base_Type (F_Typ);
10372 if Ekind (B_Typ) = E_Access_Subtype then
10373 B_Typ := Base_Type (B_Typ);
10376 if Scope (B_Typ) = Current_Scope
10377 and then not Is_Class_Wide_Type (B_Typ)
10378 and then not Is_Generic_Type (B_Typ)
10380 Is_Primitive := True;
10381 Set_Is_Primitive (S);
10382 Set_Has_Primitive_Operations (B_Typ);
10383 Check_Private_Overriding (B_Typ);
10385 -- The Ghost policy in effect at the point of declaration
10386 -- of a tagged type and a primitive operation must match
10387 -- (SPARK RM 6.9(16)).
10389 Check_Ghost_Primitive (S, B_Typ);
10392 Next_Formal (Formal);
10395 -- Special case: An equality function can be redefined for a type
10396 -- occurring in a declarative part, and won't otherwise be treated as
10397 -- a primitive because it doesn't occur in a package spec and doesn't
10398 -- override an inherited subprogram. It's important that we mark it
10399 -- primitive so it can be returned by Collect_Primitive_Operations
10400 -- and be used in composing the equality operation of later types
10401 -- that have a component of the type.
10403 elsif Chars (S) = Name_Op_Eq
10404 and then Etype (S) = Standard_Boolean
10406 B_Typ := Base_Type (Etype (First_Formal (S)));
10408 if Scope (B_Typ) = Current_Scope
10410 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10411 and then not Is_Limited_Type (B_Typ)
10413 Is_Primitive := True;
10414 Set_Is_Primitive (S);
10415 Set_Has_Primitive_Operations (B_Typ);
10416 Check_Private_Overriding (B_Typ);
10418 -- The Ghost policy in effect at the point of declaration of a
10419 -- tagged type and a primitive operation must match
10420 -- (SPARK RM 6.9(16)).
10422 Check_Ghost_Primitive (S, B_Typ);
10425 end Check_For_Primitive_Subprogram;
10427 --------------------------------------
10428 -- Has_Matching_Entry_Or_Subprogram --
10429 --------------------------------------
10431 function Has_Matching_Entry_Or_Subprogram
10432 (E : Entity_Id) return Boolean
10434 function Check_Conforming_Parameters
10435 (E1_Param : Node_Id;
10436 E2_Param : Node_Id) return Boolean;
10437 -- Starting from the given parameters, check that all the parameters
10438 -- of two entries or subprograms are subtype conformant. Used to skip
10439 -- the check on the controlling argument.
10441 function Matching_Entry_Or_Subprogram
10442 (Conc_Typ : Entity_Id;
10443 Subp : Entity_Id) return Entity_Id;
10444 -- Return the first entry or subprogram of the given concurrent type
10445 -- whose name matches the name of Subp and has a profile conformant
10446 -- with Subp; return Empty if not found.
10448 function Matching_Dispatching_Subprogram
10449 (Conc_Typ : Entity_Id;
10450 Ent : Entity_Id) return Entity_Id;
10451 -- Return the first dispatching primitive of Conc_Type defined in the
10452 -- enclosing scope of Conc_Type (i.e. before the full definition of
10453 -- this concurrent type) whose name matches the entry Ent and has a
10454 -- profile conformant with the profile of the corresponding (not yet
10455 -- built) dispatching primitive of Ent; return Empty if not found.
10457 function Matching_Original_Protected_Subprogram
10458 (Prot_Typ : Entity_Id;
10459 Subp : Entity_Id) return Entity_Id;
10460 -- Return the first subprogram defined in the enclosing scope of
10461 -- Prot_Typ (before the full definition of this protected type)
10462 -- whose name matches the original name of Subp and has a profile
10463 -- conformant with the profile of Subp; return Empty if not found.
10465 ---------------------------------
10466 -- Check_Conforming_Parameters --
10467 ---------------------------------
10469 function Check_Conforming_Parameters
10470 (E1_Param : Node_Id;
10471 E2_Param : Node_Id) return Boolean
10473 Param_E1 : Node_Id := E1_Param;
10474 Param_E2 : Node_Id := E2_Param;
10477 while Present (Param_E1) and then Present (Param_E2) loop
10478 if Ekind (Defining_Identifier (Param_E1)) /=
10479 Ekind (Defining_Identifier (Param_E2))
10482 (Find_Parameter_Type (Param_E1),
10483 Find_Parameter_Type (Param_E2),
10484 Subtype_Conformant)
10493 -- The candidate is not valid if one of the two lists contains
10494 -- more parameters than the other
10496 return No (Param_E1) and then No (Param_E2);
10497 end Check_Conforming_Parameters;
10499 ----------------------------------
10500 -- Matching_Entry_Or_Subprogram --
10501 ----------------------------------
10503 function Matching_Entry_Or_Subprogram
10504 (Conc_Typ : Entity_Id;
10505 Subp : Entity_Id) return Entity_Id
10510 E := First_Entity (Conc_Typ);
10511 while Present (E) loop
10512 if Chars (Subp) = Chars (E)
10513 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10515 Check_Conforming_Parameters
10516 (First (Parameter_Specifications (Parent (E))),
10517 Next (First (Parameter_Specifications (Parent (Subp)))))
10526 end Matching_Entry_Or_Subprogram;
10528 -------------------------------------
10529 -- Matching_Dispatching_Subprogram --
10530 -------------------------------------
10532 function Matching_Dispatching_Subprogram
10533 (Conc_Typ : Entity_Id;
10534 Ent : Entity_Id) return Entity_Id
10539 -- Search for entities in the enclosing scope of this synchonized
10542 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10543 Push_Scope (Scope (Conc_Typ));
10544 E := Current_Entity_In_Scope (Ent);
10547 while Present (E) loop
10548 if Scope (E) = Scope (Conc_Typ)
10549 and then Comes_From_Source (E)
10550 and then Ekind (E) = E_Procedure
10551 and then Present (First_Entity (E))
10552 and then Is_Controlling_Formal (First_Entity (E))
10553 and then Etype (First_Entity (E)) = Conc_Typ
10555 Check_Conforming_Parameters
10556 (First (Parameter_Specifications (Parent (Ent))),
10557 Next (First (Parameter_Specifications (Parent (E)))))
10566 end Matching_Dispatching_Subprogram;
10568 --------------------------------------------
10569 -- Matching_Original_Protected_Subprogram --
10570 --------------------------------------------
10572 function Matching_Original_Protected_Subprogram
10573 (Prot_Typ : Entity_Id;
10574 Subp : Entity_Id) return Entity_Id
10576 ICF : constant Boolean :=
10577 Is_Controlling_Formal (First_Entity (Subp));
10581 -- Temporarily decorate the first parameter of Subp as controlling
10582 -- formal, required to invoke Subtype_Conformant.
10584 Set_Is_Controlling_Formal (First_Entity (Subp));
10587 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10589 while Present (E) loop
10590 if Scope (E) = Scope (Prot_Typ)
10591 and then Comes_From_Source (E)
10592 and then Ekind (Subp) = Ekind (E)
10593 and then Present (First_Entity (E))
10594 and then Is_Controlling_Formal (First_Entity (E))
10595 and then Etype (First_Entity (E)) = Prot_Typ
10596 and then Subtype_Conformant (Subp, E,
10597 Skip_Controlling_Formals => True)
10599 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10606 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10609 end Matching_Original_Protected_Subprogram;
10611 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10614 -- Case 1: E is a subprogram whose first formal is a concurrent type
10615 -- defined in the scope of E that has an entry or subprogram whose
10616 -- profile matches E.
10618 if Comes_From_Source (E)
10619 and then Is_Subprogram (E)
10620 and then Present (First_Entity (E))
10621 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10624 Scope (Corresponding_Concurrent_Type
10625 (Etype (First_Entity (E))))
10628 (Matching_Entry_Or_Subprogram
10629 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10632 Report_Conflict (E,
10633 Matching_Entry_Or_Subprogram
10634 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10639 -- Case 2: E is an internally built dispatching subprogram of a
10640 -- protected type and there is a subprogram defined in the enclosing
10641 -- scope of the protected type that has the original name of E and
10642 -- its profile is conformant with the profile of E. We check the
10643 -- name of the original protected subprogram associated with E since
10644 -- the expander builds dispatching primitives of protected functions
10645 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10647 elsif not Comes_From_Source (E)
10648 and then Is_Subprogram (E)
10649 and then Present (First_Entity (E))
10650 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10651 and then Present (Original_Protected_Subprogram (E))
10654 (Matching_Original_Protected_Subprogram
10655 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10658 Report_Conflict (E,
10659 Matching_Original_Protected_Subprogram
10660 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10664 -- Case 3: E is an entry of a synchronized type and a matching
10665 -- procedure has been previously defined in the enclosing scope
10666 -- of the synchronized type.
10668 elsif Comes_From_Source (E)
10669 and then Ekind (E) = E_Entry
10671 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10673 Report_Conflict (E,
10674 Matching_Dispatching_Subprogram (Current_Scope, E));
10679 end Has_Matching_Entry_Or_Subprogram;
10681 ----------------------------
10682 -- Is_Private_Declaration --
10683 ----------------------------
10685 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10686 Decl : constant Node_Id := Unit_Declaration_Node (E);
10687 Priv_Decls : List_Id;
10690 if Is_Package_Or_Generic_Package (Current_Scope)
10691 and then In_Private_Part (Current_Scope)
10694 Private_Declarations (Package_Specification (Current_Scope));
10696 return In_Package_Body (Current_Scope)
10698 (Is_List_Member (Decl)
10699 and then List_Containing (Decl) = Priv_Decls)
10700 or else (Nkind (Parent (Decl)) = N_Package_Specification
10702 Is_Compilation_Unit
10703 (Defining_Entity (Parent (Decl)))
10704 and then List_Containing (Parent (Parent (Decl))) =
10709 end Is_Private_Declaration;
10711 --------------------------
10712 -- Is_Overriding_Alias --
10713 --------------------------
10715 function Is_Overriding_Alias
10716 (Old_E : Entity_Id;
10717 New_E : Entity_Id) return Boolean
10719 AO : constant Entity_Id := Alias (Old_E);
10720 AN : constant Entity_Id := Alias (New_E);
10723 return Scope (AO) /= Scope (AN)
10724 or else No (DTC_Entity (AO))
10725 or else No (DTC_Entity (AN))
10726 or else DT_Position (AO) = DT_Position (AN);
10727 end Is_Overriding_Alias;
10729 ---------------------
10730 -- Report_Conflict --
10731 ---------------------
10733 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10735 Error_Msg_Sloc := Sloc (E);
10737 -- Generate message, with useful additional warning if in generic
10739 if Is_Generic_Unit (E) then
10740 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10741 Error_Msg_N ("\& conflicts with declaration#", S);
10743 Error_Msg_N ("& conflicts with declaration#", S);
10745 end Report_Conflict;
10747 -- Start of processing for New_Overloaded_Entity
10750 -- We need to look for an entity that S may override. This must be a
10751 -- homonym in the current scope, so we look for the first homonym of
10752 -- S in the current scope as the starting point for the search.
10754 E := Current_Entity_In_Scope (S);
10756 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10757 -- They are directly added to the list of primitive operations of
10758 -- Derived_Type, unless this is a rederivation in the private part
10759 -- of an operation that was already derived in the visible part of
10760 -- the current package.
10762 if Ada_Version >= Ada_2005
10763 and then Present (Derived_Type)
10764 and then Present (Alias (S))
10765 and then Is_Dispatching_Operation (Alias (S))
10766 and then Present (Find_Dispatching_Type (Alias (S)))
10767 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10769 -- For private types, when the full-view is processed we propagate to
10770 -- the full view the non-overridden entities whose attribute "alias"
10771 -- references an interface primitive. These entities were added by
10772 -- Derive_Subprograms to ensure that interface primitives are
10775 -- Inside_Freeze_Actions is non zero when S corresponds with an
10776 -- internal entity that links an interface primitive with its
10777 -- covering primitive through attribute Interface_Alias (see
10778 -- Add_Internal_Interface_Entities).
10780 if Inside_Freezing_Actions = 0
10781 and then Is_Package_Or_Generic_Package (Current_Scope)
10782 and then In_Private_Part (Current_Scope)
10783 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10784 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10785 and then Full_View (Defining_Identifier (Parent (E)))
10786 = Defining_Identifier (Parent (S))
10787 and then Alias (E) = Alias (S)
10789 Check_Operation_From_Private_View (S, E);
10790 Set_Is_Dispatching_Operation (S);
10795 Enter_Overloaded_Entity (S);
10796 Check_Dispatching_Operation (S, Empty);
10797 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10803 -- For synchronized types check conflicts of this entity with previously
10804 -- defined entities.
10806 if Ada_Version >= Ada_2005
10807 and then Has_Matching_Entry_Or_Subprogram (S)
10812 -- If there is no homonym then this is definitely not overriding
10815 Enter_Overloaded_Entity (S);
10816 Check_Dispatching_Operation (S, Empty);
10817 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10819 -- If subprogram has an explicit declaration, check whether it has an
10820 -- overriding indicator.
10822 if Comes_From_Source (S) then
10823 Check_Synchronized_Overriding (S, Overridden_Subp);
10825 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10826 -- it may have overridden some hidden inherited primitive. Update
10827 -- Overridden_Subp to avoid spurious errors when checking the
10828 -- overriding indicator.
10830 if Ada_Version >= Ada_2012
10831 and then No (Overridden_Subp)
10832 and then Is_Dispatching_Operation (S)
10833 and then Present (Overridden_Operation (S))
10835 Overridden_Subp := Overridden_Operation (S);
10838 Check_Overriding_Indicator
10839 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10841 -- The Ghost policy in effect at the point of declaration of a
10842 -- parent subprogram and an overriding subprogram must match
10843 -- (SPARK RM 6.9(17)).
10845 Check_Ghost_Overriding (S, Overridden_Subp);
10848 -- If there is a homonym that is not overloadable, then we have an
10849 -- error, except for the special cases checked explicitly below.
10851 elsif not Is_Overloadable (E) then
10853 -- Check for spurious conflict produced by a subprogram that has the
10854 -- same name as that of the enclosing generic package. The conflict
10855 -- occurs within an instance, between the subprogram and the renaming
10856 -- declaration for the package. After the subprogram, the package
10857 -- renaming declaration becomes hidden.
10859 if Ekind (E) = E_Package
10860 and then Present (Renamed_Object (E))
10861 and then Renamed_Object (E) = Current_Scope
10862 and then Nkind (Parent (Renamed_Object (E))) =
10863 N_Package_Specification
10864 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10867 Set_Is_Immediately_Visible (E, False);
10868 Enter_Overloaded_Entity (S);
10869 Set_Homonym (S, Homonym (E));
10870 Check_Dispatching_Operation (S, Empty);
10871 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10873 -- If the subprogram is implicit it is hidden by the previous
10874 -- declaration. However if it is dispatching, it must appear in the
10875 -- dispatch table anyway, because it can be dispatched to even if it
10876 -- cannot be called directly.
10878 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10879 Set_Scope (S, Current_Scope);
10881 if Is_Dispatching_Operation (Alias (S)) then
10882 Check_Dispatching_Operation (S, Empty);
10888 Report_Conflict (S, E);
10892 -- E exists and is overloadable
10895 Check_Synchronized_Overriding (S, Overridden_Subp);
10897 -- Loop through E and its homonyms to determine if any of them is
10898 -- the candidate for overriding by S.
10900 while Present (E) loop
10902 -- Definitely not interesting if not in the current scope
10904 if Scope (E) /= Current_Scope then
10907 -- A function can overload the name of an abstract state. The
10908 -- state can be viewed as a function with a profile that cannot
10909 -- be matched by anything.
10911 elsif Ekind (S) = E_Function
10912 and then Ekind (E) = E_Abstract_State
10914 Enter_Overloaded_Entity (S);
10917 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10918 -- procedures locate the internally generated spec. We enforce
10919 -- mode conformance since a tagged type may inherit from
10920 -- interfaces several null primitives which differ only in
10921 -- the mode of the formals.
10923 elsif not Comes_From_Source (S)
10924 and then Is_Null_Procedure (S)
10925 and then not Mode_Conformant (E, S)
10929 -- Check if we have type conformance
10931 elsif Type_Conformant (E, S) then
10933 -- If the old and new entities have the same profile and one
10934 -- is not the body of the other, then this is an error, unless
10935 -- one of them is implicitly declared.
10937 -- There are some cases when both can be implicit, for example
10938 -- when both a literal and a function that overrides it are
10939 -- inherited in a derivation, or when an inherited operation
10940 -- of a tagged full type overrides the inherited operation of
10941 -- a private extension. Ada 83 had a special rule for the
10942 -- literal case. In Ada 95, the later implicit operation hides
10943 -- the former, and the literal is always the former. In the
10944 -- odd case where both are derived operations declared at the
10945 -- same point, both operations should be declared, and in that
10946 -- case we bypass the following test and proceed to the next
10947 -- part. This can only occur for certain obscure cases in
10948 -- instances, when an operation on a type derived from a formal
10949 -- private type does not override a homograph inherited from
10950 -- the actual. In subsequent derivations of such a type, the
10951 -- DT positions of these operations remain distinct, if they
10954 if Present (Alias (S))
10955 and then (No (Alias (E))
10956 or else Comes_From_Source (E)
10957 or else Is_Abstract_Subprogram (S)
10959 (Is_Dispatching_Operation (E)
10960 and then Is_Overriding_Alias (E, S)))
10961 and then Ekind (E) /= E_Enumeration_Literal
10963 -- When an derived operation is overloaded it may be due to
10964 -- the fact that the full view of a private extension
10965 -- re-inherits. It has to be dealt with.
10967 if Is_Package_Or_Generic_Package (Current_Scope)
10968 and then In_Private_Part (Current_Scope)
10970 Check_Operation_From_Private_View (S, E);
10973 -- In any case the implicit operation remains hidden by the
10974 -- existing declaration, which is overriding. Indicate that
10975 -- E overrides the operation from which S is inherited.
10977 if Present (Alias (S)) then
10978 Set_Overridden_Operation (E, Alias (S));
10979 Inherit_Subprogram_Contract (E, Alias (S));
10982 Set_Overridden_Operation (E, S);
10983 Inherit_Subprogram_Contract (E, S);
10986 if Comes_From_Source (E) then
10987 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10989 -- The Ghost policy in effect at the point of declaration
10990 -- of a parent subprogram and an overriding subprogram
10991 -- must match (SPARK RM 6.9(17)).
10993 Check_Ghost_Overriding (E, S);
10998 -- Within an instance, the renaming declarations for actual
10999 -- subprograms may become ambiguous, but they do not hide each
11002 elsif Ekind (E) /= E_Entry
11003 and then not Comes_From_Source (E)
11004 and then not Is_Generic_Instance (E)
11005 and then (Present (Alias (E))
11006 or else Is_Intrinsic_Subprogram (E))
11007 and then (not In_Instance
11008 or else No (Parent (E))
11009 or else Nkind (Unit_Declaration_Node (E)) /=
11010 N_Subprogram_Renaming_Declaration)
11012 -- A subprogram child unit is not allowed to override an
11013 -- inherited subprogram (10.1.1(20)).
11015 if Is_Child_Unit (S) then
11017 ("child unit overrides inherited subprogram in parent",
11022 if Is_Non_Overriding_Operation (E, S) then
11023 Enter_Overloaded_Entity (S);
11025 if No (Derived_Type)
11026 or else Is_Tagged_Type (Derived_Type)
11028 Check_Dispatching_Operation (S, Empty);
11034 -- E is a derived operation or an internal operator which
11035 -- is being overridden. Remove E from further visibility.
11036 -- Furthermore, if E is a dispatching operation, it must be
11037 -- replaced in the list of primitive operations of its type
11038 -- (see Override_Dispatching_Operation).
11040 Overridden_Subp := E;
11042 -- It is possible for E to be in the current scope and
11043 -- yet not in the entity chain. This can only occur in a
11044 -- generic context where E is an implicit concatenation
11045 -- in the formal part, because in a generic body the
11046 -- entity chain starts with the formals.
11048 -- In GNATprove mode, a wrapper for an operation with
11049 -- axiomatization may be a homonym of another declaration
11050 -- for an actual subprogram (needs refinement ???).
11052 if No (Prev_Entity (E)) then
11054 and then GNATprove_Mode
11056 Nkind (Original_Node (Unit_Declaration_Node (S))) =
11057 N_Subprogram_Renaming_Declaration
11061 pragma Assert (Chars (E) = Name_Op_Concat);
11066 -- E must be removed both from the entity_list of the
11067 -- current scope, and from the visibility chain.
11069 if Debug_Flag_E then
11070 Write_Str ("Override implicit operation ");
11071 Write_Int (Int (E));
11075 -- If E is a predefined concatenation, it stands for four
11076 -- different operations. As a result, a single explicit
11077 -- declaration does not hide it. In a possible ambiguous
11078 -- situation, Disambiguate chooses the user-defined op,
11079 -- so it is correct to retain the previous internal one.
11081 if Chars (E) /= Name_Op_Concat
11082 or else Ekind (E) /= E_Operator
11084 -- For nondispatching derived operations that are
11085 -- overridden by a subprogram declared in the private
11086 -- part of a package, we retain the derived subprogram
11087 -- but mark it as not immediately visible. If the
11088 -- derived operation was declared in the visible part
11089 -- then this ensures that it will still be visible
11090 -- outside the package with the proper signature
11091 -- (calls from outside must also be directed to this
11092 -- version rather than the overriding one, unlike the
11093 -- dispatching case). Calls from inside the package
11094 -- will still resolve to the overriding subprogram
11095 -- since the derived one is marked as not visible
11096 -- within the package.
11098 -- If the private operation is dispatching, we achieve
11099 -- the overriding by keeping the implicit operation
11100 -- but setting its alias to be the overriding one. In
11101 -- this fashion the proper body is executed in all
11102 -- cases, but the original signature is used outside
11105 -- If the overriding is not in the private part, we
11106 -- remove the implicit operation altogether.
11108 if Is_Private_Declaration (S) then
11109 if not Is_Dispatching_Operation (E) then
11110 Set_Is_Immediately_Visible (E, False);
11112 -- Work done in Override_Dispatching_Operation, so
11113 -- nothing else needs to be done here.
11119 Remove_Entity_And_Homonym (E);
11123 Enter_Overloaded_Entity (S);
11125 -- For entities generated by Derive_Subprograms the
11126 -- overridden operation is the inherited primitive
11127 -- (which is available through the attribute alias).
11129 if not (Comes_From_Source (E))
11130 and then Is_Dispatching_Operation (E)
11131 and then Find_Dispatching_Type (E) =
11132 Find_Dispatching_Type (S)
11133 and then Present (Alias (E))
11134 and then Comes_From_Source (Alias (E))
11136 Set_Overridden_Operation (S, Alias (E));
11137 Inherit_Subprogram_Contract (S, Alias (E));
11139 -- Normal case of setting entity as overridden
11141 -- Note: Static_Initialization and Overridden_Operation
11142 -- attributes use the same field in subprogram entities.
11143 -- Static_Initialization is only defined for internal
11144 -- initialization procedures, where Overridden_Operation
11145 -- is irrelevant. Therefore the setting of this attribute
11146 -- must check whether the target is an init_proc.
11148 elsif not Is_Init_Proc (S) then
11149 Set_Overridden_Operation (S, E);
11150 Inherit_Subprogram_Contract (S, E);
11153 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11155 -- The Ghost policy in effect at the point of declaration
11156 -- of a parent subprogram and an overriding subprogram
11157 -- must match (SPARK RM 6.9(17)).
11159 Check_Ghost_Overriding (S, E);
11161 -- If S is a user-defined subprogram or a null procedure
11162 -- expanded to override an inherited null procedure, or a
11163 -- predefined dispatching primitive then indicate that E
11164 -- overrides the operation from which S is inherited.
11166 if Comes_From_Source (S)
11168 (Present (Parent (S))
11169 and then Nkind (Parent (S)) = N_Procedure_Specification
11170 and then Null_Present (Parent (S)))
11172 (Present (Alias (E))
11174 Is_Predefined_Dispatching_Operation (Alias (E)))
11176 if Present (Alias (E)) then
11177 Set_Overridden_Operation (S, Alias (E));
11178 Inherit_Subprogram_Contract (S, Alias (E));
11182 if Is_Dispatching_Operation (E) then
11184 -- An overriding dispatching subprogram inherits the
11185 -- convention of the overridden subprogram (AI-117).
11187 Set_Convention (S, Convention (E));
11188 Check_Dispatching_Operation (S, E);
11191 Check_Dispatching_Operation (S, Empty);
11194 Check_For_Primitive_Subprogram
11195 (Is_Primitive_Subp, Is_Overriding => True);
11196 goto Check_Inequality;
11198 -- Apparent redeclarations in instances can occur when two
11199 -- formal types get the same actual type. The subprograms in
11200 -- in the instance are legal, even if not callable from the
11201 -- outside. Calls from within are disambiguated elsewhere.
11202 -- For dispatching operations in the visible part, the usual
11203 -- rules apply, and operations with the same profile are not
11204 -- legal (B830001).
11206 elsif (In_Instance_Visible_Part
11207 and then not Is_Dispatching_Operation (E))
11208 or else In_Instance_Not_Visible
11212 -- Here we have a real error (identical profile)
11215 Error_Msg_Sloc := Sloc (E);
11217 -- Avoid cascaded errors if the entity appears in
11218 -- subsequent calls.
11220 Set_Scope (S, Current_Scope);
11222 -- Generate error, with extra useful warning for the case
11223 -- of a generic instance with no completion.
11225 if Is_Generic_Instance (S)
11226 and then not Has_Completion (E)
11229 ("instantiation cannot provide body for&", S);
11230 Error_Msg_N ("\& conflicts with declaration#", S);
11232 Error_Msg_N ("& conflicts with declaration#", S);
11239 -- If one subprogram has an access parameter and the other
11240 -- a parameter of an access type, calls to either might be
11241 -- ambiguous. Verify that parameters match except for the
11242 -- access parameter.
11244 if May_Hide_Profile then
11250 F1 := First_Formal (S);
11251 F2 := First_Formal (E);
11252 while Present (F1) and then Present (F2) loop
11253 if Is_Access_Type (Etype (F1)) then
11254 if not Is_Access_Type (Etype (F2))
11255 or else not Conforming_Types
11256 (Designated_Type (Etype (F1)),
11257 Designated_Type (Etype (F2)),
11260 May_Hide_Profile := False;
11264 not Conforming_Types
11265 (Etype (F1), Etype (F2), Type_Conformant)
11267 May_Hide_Profile := False;
11274 if May_Hide_Profile
11278 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11287 -- On exit, we know that S is a new entity
11289 Enter_Overloaded_Entity (S);
11290 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11291 Check_Overriding_Indicator
11292 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11294 -- The Ghost policy in effect at the point of declaration of a parent
11295 -- subprogram and an overriding subprogram must match
11296 -- (SPARK RM 6.9(17)).
11298 Check_Ghost_Overriding (S, Overridden_Subp);
11300 -- Overloading is not allowed in SPARK, except for operators
11302 if Nkind (S) /= N_Defining_Operator_Symbol then
11303 Error_Msg_Sloc := Sloc (Homonym (S));
11304 Check_SPARK_05_Restriction
11305 ("overloading not allowed with entity#", S);
11308 -- If S is a derived operation for an untagged type then by
11309 -- definition it's not a dispatching operation (even if the parent
11310 -- operation was dispatching), so Check_Dispatching_Operation is not
11311 -- called in that case.
11313 if No (Derived_Type)
11314 or else Is_Tagged_Type (Derived_Type)
11316 Check_Dispatching_Operation (S, Empty);
11320 -- If this is a user-defined equality operator that is not a derived
11321 -- subprogram, create the corresponding inequality. If the operation is
11322 -- dispatching, the expansion is done elsewhere, and we do not create
11323 -- an explicit inequality operation.
11325 <<Check_Inequality>>
11326 if Chars (S) = Name_Op_Eq
11327 and then Etype (S) = Standard_Boolean
11328 and then Present (Parent (S))
11329 and then not Is_Dispatching_Operation (S)
11331 Make_Inequality_Operator (S);
11332 Check_Untagged_Equality (S);
11334 end New_Overloaded_Entity;
11336 ---------------------
11337 -- Process_Formals --
11338 ---------------------
11340 procedure Process_Formals
11342 Related_Nod : Node_Id)
11344 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11345 -- Determine whether an access type designates a type coming from a
11348 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11349 -- Check whether the default has a class-wide type. After analysis the
11350 -- default has the type of the formal, so we must also check explicitly
11351 -- for an access attribute.
11353 ----------------------------------
11354 -- Designates_From_Limited_With --
11355 ----------------------------------
11357 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11358 Desig : Entity_Id := Typ;
11361 if Is_Access_Type (Desig) then
11362 Desig := Directly_Designated_Type (Desig);
11365 if Is_Class_Wide_Type (Desig) then
11366 Desig := Root_Type (Desig);
11370 Ekind (Desig) = E_Incomplete_Type
11371 and then From_Limited_With (Desig);
11372 end Designates_From_Limited_With;
11374 ---------------------------
11375 -- Is_Class_Wide_Default --
11376 ---------------------------
11378 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11380 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11381 or else (Nkind (D) = N_Attribute_Reference
11382 and then Attribute_Name (D) = Name_Access
11383 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11384 end Is_Class_Wide_Default;
11388 Context : constant Node_Id := Parent (Parent (T));
11390 Formal : Entity_Id;
11391 Formal_Type : Entity_Id;
11392 Param_Spec : Node_Id;
11395 Num_Out_Params : Nat := 0;
11396 First_Out_Param : Entity_Id := Empty;
11397 -- Used for setting Is_Only_Out_Parameter
11399 -- Start of processing for Process_Formals
11402 -- In order to prevent premature use of the formals in the same formal
11403 -- part, the Ekind is left undefined until all default expressions are
11404 -- analyzed. The Ekind is established in a separate loop at the end.
11406 Param_Spec := First (T);
11407 while Present (Param_Spec) loop
11408 Formal := Defining_Identifier (Param_Spec);
11409 Set_Never_Set_In_Source (Formal, True);
11410 Enter_Name (Formal);
11412 -- Case of ordinary parameters
11414 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11415 Find_Type (Parameter_Type (Param_Spec));
11416 Ptype := Parameter_Type (Param_Spec);
11418 if Ptype = Error then
11422 Formal_Type := Entity (Ptype);
11424 if Is_Incomplete_Type (Formal_Type)
11426 (Is_Class_Wide_Type (Formal_Type)
11427 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11429 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11430 -- primitive operations, as long as their completion is
11431 -- in the same declarative part. If in the private part
11432 -- this means that the type cannot be a Taft-amendment type.
11433 -- Check is done on package exit. For access to subprograms,
11434 -- the use is legal for Taft-amendment types.
11436 -- Ada 2012: tagged incomplete types are allowed as generic
11437 -- formal types. They do not introduce dependencies and the
11438 -- corresponding generic subprogram does not have a delayed
11439 -- freeze, because it does not need a freeze node. However,
11440 -- it is still the case that untagged incomplete types cannot
11441 -- be Taft-amendment types and must be completed in private
11442 -- part, so the subprogram must appear in the list of private
11443 -- dependents of the type.
11445 if Is_Tagged_Type (Formal_Type)
11446 or else (Ada_Version >= Ada_2012
11447 and then not From_Limited_With (Formal_Type)
11448 and then not Is_Generic_Type (Formal_Type))
11450 if Ekind (Scope (Current_Scope)) = E_Package
11451 and then not Is_Generic_Type (Formal_Type)
11452 and then not Is_Class_Wide_Type (Formal_Type)
11455 (Parent (T), N_Access_Function_Definition,
11456 N_Access_Procedure_Definition)
11458 Append_Elmt (Current_Scope,
11459 Private_Dependents (Base_Type (Formal_Type)));
11461 -- Freezing is delayed to ensure that Register_Prim
11462 -- will get called for this operation, which is needed
11463 -- in cases where static dispatch tables aren't built.
11464 -- (Note that the same is done for controlling access
11465 -- parameter cases in function Access_Definition.)
11467 if not Is_Thunk (Current_Scope) then
11468 Set_Has_Delayed_Freeze (Current_Scope);
11473 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11474 N_Access_Procedure_Definition)
11476 -- AI05-0151: Tagged incomplete types are allowed in all
11477 -- formal parts. Untagged incomplete types are not allowed
11478 -- in bodies. Limited views of either kind are not allowed
11479 -- if there is no place at which the non-limited view can
11480 -- become available.
11482 -- Incomplete formal untagged types are not allowed in
11483 -- subprogram bodies (but are legal in their declarations).
11484 -- This excludes bodies created for null procedures, which
11485 -- are basic declarations.
11487 if Is_Generic_Type (Formal_Type)
11488 and then not Is_Tagged_Type (Formal_Type)
11489 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11492 ("invalid use of formal incomplete type", Param_Spec);
11494 elsif Ada_Version >= Ada_2012 then
11495 if Is_Tagged_Type (Formal_Type)
11496 and then (not From_Limited_With (Formal_Type)
11497 or else not In_Package_Body)
11501 elsif Nkind_In (Context, N_Accept_Statement,
11502 N_Accept_Alternative,
11504 or else (Nkind (Context) = N_Subprogram_Body
11505 and then Comes_From_Source (Context))
11508 ("invalid use of untagged incomplete type &",
11509 Ptype, Formal_Type);
11514 ("invalid use of incomplete type&",
11515 Param_Spec, Formal_Type);
11517 -- Further checks on the legality of incomplete types
11518 -- in formal parts are delayed until the freeze point
11519 -- of the enclosing subprogram or access to subprogram.
11523 elsif Ekind (Formal_Type) = E_Void then
11525 ("premature use of&",
11526 Parameter_Type (Param_Spec), Formal_Type);
11529 -- Ada 2012 (AI-142): Handle aliased parameters
11531 if Ada_Version >= Ada_2012
11532 and then Aliased_Present (Param_Spec)
11534 Set_Is_Aliased (Formal);
11537 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11538 -- declaration corresponding to the null-excluding type of the
11539 -- formal in the enclosing scope. Finally, replace the parameter
11540 -- type of the formal with the internal subtype.
11542 if Ada_Version >= Ada_2005
11543 and then Null_Exclusion_Present (Param_Spec)
11545 if not Is_Access_Type (Formal_Type) then
11547 ("`NOT NULL` allowed only for an access type", Param_Spec);
11550 if Can_Never_Be_Null (Formal_Type)
11551 and then Comes_From_Source (Related_Nod)
11554 ("`NOT NULL` not allowed (& already excludes null)",
11555 Param_Spec, Formal_Type);
11559 Create_Null_Excluding_Itype
11561 Related_Nod => Related_Nod,
11562 Scope_Id => Scope (Current_Scope));
11564 -- If the designated type of the itype is an itype that is
11565 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11566 -- on the access subtype, to prevent order-of-elaboration
11567 -- issues in the backend.
11570 -- type T is access procedure;
11571 -- procedure Op (O : not null T);
11573 if Is_Itype (Directly_Designated_Type (Formal_Type))
11575 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11577 Set_Has_Delayed_Freeze (Formal_Type);
11582 -- An access formal type
11586 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11588 -- No need to continue if we already notified errors
11590 if not Present (Formal_Type) then
11594 -- Ada 2005 (AI-254)
11597 AD : constant Node_Id :=
11598 Access_To_Subprogram_Definition
11599 (Parameter_Type (Param_Spec));
11601 if Present (AD) and then Protected_Present (AD) then
11603 Replace_Anonymous_Access_To_Protected_Subprogram
11609 Set_Etype (Formal, Formal_Type);
11611 -- Deal with default expression if present
11613 Default := Expression (Param_Spec);
11615 if Present (Default) then
11616 Check_SPARK_05_Restriction
11617 ("default expression is not allowed", Default);
11619 if Out_Present (Param_Spec) then
11621 ("default initialization only allowed for IN parameters",
11625 -- Do the special preanalysis of the expression (see section on
11626 -- "Handling of Default Expressions" in the spec of package Sem).
11628 Preanalyze_Spec_Expression (Default, Formal_Type);
11630 -- An access to constant cannot be the default for
11631 -- an access parameter that is an access to variable.
11633 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11634 and then not Is_Access_Constant (Formal_Type)
11635 and then Is_Access_Type (Etype (Default))
11636 and then Is_Access_Constant (Etype (Default))
11639 ("formal that is access to variable cannot be initialized "
11640 & "with an access-to-constant expression", Default);
11643 -- Check that the designated type of an access parameter's default
11644 -- is not a class-wide type unless the parameter's designated type
11645 -- is also class-wide.
11647 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11648 and then not Designates_From_Limited_With (Formal_Type)
11649 and then Is_Class_Wide_Default (Default)
11650 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11653 ("access to class-wide expression not allowed here", Default);
11656 -- Check incorrect use of dynamically tagged expressions
11658 if Is_Tagged_Type (Formal_Type) then
11659 Check_Dynamically_Tagged_Expression
11661 Typ => Formal_Type,
11662 Related_Nod => Default);
11666 -- Ada 2005 (AI-231): Static checks
11668 if Ada_Version >= Ada_2005
11669 and then Is_Access_Type (Etype (Formal))
11670 and then Can_Never_Be_Null (Etype (Formal))
11672 Null_Exclusion_Static_Checks (Param_Spec);
11675 -- The following checks are relevant only when SPARK_Mode is on as
11676 -- these are not standard Ada legality rules.
11678 if SPARK_Mode = On then
11679 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11681 -- A function cannot have a parameter of mode IN OUT or OUT
11684 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11686 ("function cannot have parameter of mode `OUT` or "
11687 & "`IN OUT`", Formal);
11690 -- A procedure cannot have an effectively volatile formal
11691 -- parameter of mode IN because it behaves as a constant
11692 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11694 elsif Ekind (Scope (Formal)) = E_Procedure
11695 and then Ekind (Formal) = E_In_Parameter
11696 and then Is_Effectively_Volatile (Formal)
11699 ("formal parameter of mode `IN` cannot be volatile", Formal);
11707 -- If this is the formal part of a function specification, analyze the
11708 -- subtype mark in the context where the formals are visible but not
11709 -- yet usable, and may hide outer homographs.
11711 if Nkind (Related_Nod) = N_Function_Specification then
11712 Analyze_Return_Type (Related_Nod);
11715 -- Now set the kind (mode) of each formal
11717 Param_Spec := First (T);
11718 while Present (Param_Spec) loop
11719 Formal := Defining_Identifier (Param_Spec);
11720 Set_Formal_Mode (Formal);
11722 if Ekind (Formal) = E_In_Parameter then
11723 Set_Default_Value (Formal, Expression (Param_Spec));
11725 if Present (Expression (Param_Spec)) then
11726 Default := Expression (Param_Spec);
11728 if Is_Scalar_Type (Etype (Default)) then
11729 if Nkind (Parameter_Type (Param_Spec)) /=
11730 N_Access_Definition
11732 Formal_Type := Entity (Parameter_Type (Param_Spec));
11736 (Related_Nod, Parameter_Type (Param_Spec));
11739 Apply_Scalar_Range_Check (Default, Formal_Type);
11743 elsif Ekind (Formal) = E_Out_Parameter then
11744 Num_Out_Params := Num_Out_Params + 1;
11746 if Num_Out_Params = 1 then
11747 First_Out_Param := Formal;
11750 elsif Ekind (Formal) = E_In_Out_Parameter then
11751 Num_Out_Params := Num_Out_Params + 1;
11754 -- Skip remaining processing if formal type was in error
11756 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11757 goto Next_Parameter;
11760 -- Force call by reference if aliased
11763 Conv : constant Convention_Id := Convention (Etype (Formal));
11765 if Is_Aliased (Formal) then
11766 Set_Mechanism (Formal, By_Reference);
11768 -- Warn if user asked this to be passed by copy
11770 if Conv = Convention_Ada_Pass_By_Copy then
11772 ("cannot pass aliased parameter & by copy??", Formal);
11775 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11777 elsif Conv = Convention_Ada_Pass_By_Copy then
11778 Set_Mechanism (Formal, By_Copy);
11780 elsif Conv = Convention_Ada_Pass_By_Reference then
11781 Set_Mechanism (Formal, By_Reference);
11789 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11790 Set_Is_Only_Out_Parameter (First_Out_Param);
11792 end Process_Formals;
11794 ----------------------------
11795 -- Reference_Body_Formals --
11796 ----------------------------
11798 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11803 if Error_Posted (Spec) then
11807 -- Iterate over both lists. They may be of different lengths if the two
11808 -- specs are not conformant.
11810 Fs := First_Formal (Spec);
11811 Fb := First_Formal (Bod);
11812 while Present (Fs) and then Present (Fb) loop
11813 Generate_Reference (Fs, Fb, 'b');
11815 if Style_Check then
11816 Style.Check_Identifier (Fb, Fs);
11819 Set_Spec_Entity (Fb, Fs);
11820 Set_Referenced (Fs, False);
11824 end Reference_Body_Formals;
11826 -------------------------
11827 -- Set_Actual_Subtypes --
11828 -------------------------
11830 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11832 Formal : Entity_Id;
11834 First_Stmt : Node_Id := Empty;
11835 AS_Needed : Boolean;
11838 -- If this is an empty initialization procedure, no need to create
11839 -- actual subtypes (small optimization).
11841 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11844 -- Within a predicate function we do not want to generate local
11845 -- subtypes that may generate nested predicate functions.
11847 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11851 -- The subtype declarations may freeze the formals. The body generated
11852 -- for an expression function is not a freeze point, so do not emit
11853 -- these declarations (small loss of efficiency in rare cases).
11855 if Nkind (N) = N_Subprogram_Body
11856 and then Was_Expression_Function (N)
11861 Formal := First_Formal (Subp);
11862 while Present (Formal) loop
11863 T := Etype (Formal);
11865 -- We never need an actual subtype for a constrained formal
11867 if Is_Constrained (T) then
11868 AS_Needed := False;
11870 -- If we have unknown discriminants, then we do not need an actual
11871 -- subtype, or more accurately we cannot figure it out. Note that
11872 -- all class-wide types have unknown discriminants.
11874 elsif Has_Unknown_Discriminants (T) then
11875 AS_Needed := False;
11877 -- At this stage we have an unconstrained type that may need an
11878 -- actual subtype. For sure the actual subtype is needed if we have
11879 -- an unconstrained array type. However, in an instance, the type
11880 -- may appear as a subtype of the full view, while the actual is
11881 -- in fact private (in which case no actual subtype is needed) so
11882 -- check the kind of the base type.
11884 elsif Is_Array_Type (Base_Type (T)) then
11887 -- The only other case needing an actual subtype is an unconstrained
11888 -- record type which is an IN parameter (we cannot generate actual
11889 -- subtypes for the OUT or IN OUT case, since an assignment can
11890 -- change the discriminant values. However we exclude the case of
11891 -- initialization procedures, since discriminants are handled very
11892 -- specially in this context, see the section entitled "Handling of
11893 -- Discriminants" in Einfo.
11895 -- We also exclude the case of Discrim_SO_Functions (functions used
11896 -- in front-end layout mode for size/offset values), since in such
11897 -- functions only discriminants are referenced, and not only are such
11898 -- subtypes not needed, but they cannot always be generated, because
11899 -- of order of elaboration issues.
11901 elsif Is_Record_Type (T)
11902 and then Ekind (Formal) = E_In_Parameter
11903 and then Chars (Formal) /= Name_uInit
11904 and then not Is_Unchecked_Union (T)
11905 and then not Is_Discrim_SO_Function (Subp)
11909 -- All other cases do not need an actual subtype
11912 AS_Needed := False;
11915 -- Generate actual subtypes for unconstrained arrays and
11916 -- unconstrained discriminated records.
11919 if Nkind (N) = N_Accept_Statement then
11921 -- If expansion is active, the formal is replaced by a local
11922 -- variable that renames the corresponding entry of the
11923 -- parameter block, and it is this local variable that may
11924 -- require an actual subtype.
11926 if Expander_Active then
11927 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11929 Decl := Build_Actual_Subtype (T, Formal);
11932 if Present (Handled_Statement_Sequence (N)) then
11934 First (Statements (Handled_Statement_Sequence (N)));
11935 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11936 Mark_Rewrite_Insertion (Decl);
11938 -- If the accept statement has no body, there will be no
11939 -- reference to the actuals, so no need to compute actual
11946 Decl := Build_Actual_Subtype (T, Formal);
11947 Prepend (Decl, Declarations (N));
11948 Mark_Rewrite_Insertion (Decl);
11951 -- The declaration uses the bounds of an existing object, and
11952 -- therefore needs no constraint checks.
11954 Analyze (Decl, Suppress => All_Checks);
11955 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11957 -- We need to freeze manually the generated type when it is
11958 -- inserted anywhere else than in a declarative part.
11960 if Present (First_Stmt) then
11961 Insert_List_Before_And_Analyze (First_Stmt,
11962 Freeze_Entity (Defining_Identifier (Decl), N));
11964 -- Ditto if the type has a dynamic predicate, because the
11965 -- generated function will mention the actual subtype. The
11966 -- predicate may come from an explicit aspect of be inherited.
11968 elsif Has_Predicates (T) then
11969 Insert_List_Before_And_Analyze (Decl,
11970 Freeze_Entity (Defining_Identifier (Decl), N));
11973 if Nkind (N) = N_Accept_Statement
11974 and then Expander_Active
11976 Set_Actual_Subtype (Renamed_Object (Formal),
11977 Defining_Identifier (Decl));
11979 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11983 Next_Formal (Formal);
11985 end Set_Actual_Subtypes;
11987 ---------------------
11988 -- Set_Formal_Mode --
11989 ---------------------
11991 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11992 Spec : constant Node_Id := Parent (Formal_Id);
11993 Id : constant Entity_Id := Scope (Formal_Id);
11996 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11997 -- since we ensure that corresponding actuals are always valid at the
11998 -- point of the call.
12000 if Out_Present (Spec) then
12001 if Ekind_In (Id, E_Entry, E_Entry_Family)
12002 or else Is_Subprogram_Or_Generic_Subprogram (Id)
12004 Set_Has_Out_Or_In_Out_Parameter (Id, True);
12007 if Ekind_In (Id, E_Function, E_Generic_Function) then
12009 -- [IN] OUT parameters allowed for functions in Ada 2012
12011 if Ada_Version >= Ada_2012 then
12013 -- Even in Ada 2012 operators can only have IN parameters
12015 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
12016 Error_Msg_N ("operators can only have IN parameters", Spec);
12019 if In_Present (Spec) then
12020 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12022 Set_Ekind (Formal_Id, E_Out_Parameter);
12025 -- But not in earlier versions of Ada
12028 Error_Msg_N ("functions can only have IN parameters", Spec);
12029 Set_Ekind (Formal_Id, E_In_Parameter);
12032 elsif In_Present (Spec) then
12033 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12036 Set_Ekind (Formal_Id, E_Out_Parameter);
12037 Set_Never_Set_In_Source (Formal_Id, True);
12038 Set_Is_True_Constant (Formal_Id, False);
12039 Set_Current_Value (Formal_Id, Empty);
12043 Set_Ekind (Formal_Id, E_In_Parameter);
12046 -- Set Is_Known_Non_Null for access parameters since the language
12047 -- guarantees that access parameters are always non-null. We also set
12048 -- Can_Never_Be_Null, since there is no way to change the value.
12050 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
12052 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
12053 -- null; In Ada 2005, only if then null_exclusion is explicit.
12055 if Ada_Version < Ada_2005
12056 or else Can_Never_Be_Null (Etype (Formal_Id))
12058 Set_Is_Known_Non_Null (Formal_Id);
12059 Set_Can_Never_Be_Null (Formal_Id);
12062 -- Ada 2005 (AI-231): Null-exclusion access subtype
12064 elsif Is_Access_Type (Etype (Formal_Id))
12065 and then Can_Never_Be_Null (Etype (Formal_Id))
12067 Set_Is_Known_Non_Null (Formal_Id);
12069 -- We can also set Can_Never_Be_Null (thus preventing some junk
12070 -- access checks) for the case of an IN parameter, which cannot
12071 -- be changed, or for an IN OUT parameter, which can be changed but
12072 -- not to a null value. But for an OUT parameter, the initial value
12073 -- passed in can be null, so we can't set this flag in that case.
12075 if Ekind (Formal_Id) /= E_Out_Parameter then
12076 Set_Can_Never_Be_Null (Formal_Id);
12080 Set_Mechanism (Formal_Id, Default_Mechanism);
12081 Set_Formal_Validity (Formal_Id);
12082 end Set_Formal_Mode;
12084 -------------------------
12085 -- Set_Formal_Validity --
12086 -------------------------
12088 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12090 -- If no validity checking, then we cannot assume anything about the
12091 -- validity of parameters, since we do not know there is any checking
12092 -- of the validity on the call side.
12094 if not Validity_Checks_On then
12097 -- If validity checking for parameters is enabled, this means we are
12098 -- not supposed to make any assumptions about argument values.
12100 elsif Validity_Check_Parameters then
12103 -- If we are checking in parameters, we will assume that the caller is
12104 -- also checking parameters, so we can assume the parameter is valid.
12106 elsif Ekind (Formal_Id) = E_In_Parameter
12107 and then Validity_Check_In_Params
12109 Set_Is_Known_Valid (Formal_Id, True);
12111 -- Similar treatment for IN OUT parameters
12113 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12114 and then Validity_Check_In_Out_Params
12116 Set_Is_Known_Valid (Formal_Id, True);
12118 end Set_Formal_Validity;
12120 ------------------------
12121 -- Subtype_Conformant --
12122 ------------------------
12124 function Subtype_Conformant
12125 (New_Id : Entity_Id;
12126 Old_Id : Entity_Id;
12127 Skip_Controlling_Formals : Boolean := False) return Boolean
12131 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12132 Skip_Controlling_Formals => Skip_Controlling_Formals);
12134 end Subtype_Conformant;
12136 ---------------------
12137 -- Type_Conformant --
12138 ---------------------
12140 function Type_Conformant
12141 (New_Id : Entity_Id;
12142 Old_Id : Entity_Id;
12143 Skip_Controlling_Formals : Boolean := False) return Boolean
12147 May_Hide_Profile := False;
12149 (New_Id, Old_Id, Type_Conformant, False, Result,
12150 Skip_Controlling_Formals => Skip_Controlling_Formals);
12152 end Type_Conformant;
12154 -------------------------------
12155 -- Valid_Operator_Definition --
12156 -------------------------------
12158 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12161 Id : constant Name_Id := Chars (Designator);
12165 F := First_Formal (Designator);
12166 while Present (F) loop
12169 if Present (Default_Value (F)) then
12171 ("default values not allowed for operator parameters",
12174 -- For function instantiations that are operators, we must check
12175 -- separately that the corresponding generic only has in-parameters.
12176 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12177 -- an error could not arise in earlier versions of the language.
12179 elsif Ekind (F) /= E_In_Parameter then
12180 Error_Msg_N ("operators can only have IN parameters", F);
12186 -- Verify that user-defined operators have proper number of arguments
12187 -- First case of operators which can only be unary
12189 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12192 -- Case of operators which can be unary or binary
12194 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12195 N_OK := (N in 1 .. 2);
12197 -- All other operators can only be binary
12205 ("incorrect number of arguments for operator", Designator);
12209 and then Base_Type (Etype (Designator)) = Standard_Boolean
12210 and then not Is_Intrinsic_Subprogram (Designator)
12213 ("explicit definition of inequality not allowed", Designator);
12215 end Valid_Operator_Definition;