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 pre-analyze 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 -- Relocate the aspects and relevant pragmas from the subprogram body
2716 -- to the generated spec because it acts as the initial declaration.
2718 Insert_Before (N, Subp_Decl);
2719 Move_Aspects (N, To => Subp_Decl);
2720 Move_Pragmas (N, To => Subp_Decl);
2722 -- Ensure that the generated corresponding spec and original body
2723 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2724 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2725 -- correctly set for local subprograms.
2727 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2729 Analyze (Subp_Decl);
2731 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2732 -- the body since the expander may generate calls using that entity.
2733 -- Required to ensure that Expand_Call rewrites calls to this
2734 -- function by calls to the built procedure.
2736 if Modify_Tree_For_C
2737 and then Nkind (Body_Spec) = N_Function_Specification
2739 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2741 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2742 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2743 Corresponding_Procedure
2744 (Defining_Entity (Specification (Subp_Decl))));
2747 -- Analyze any relocated source pragmas or pragmas created for aspect
2750 Decl := Next (Subp_Decl);
2751 while Present (Decl) loop
2753 -- Stop the search for pragmas once the body has been reached as
2754 -- this terminates the region where pragmas may appear.
2759 elsif Nkind (Decl) = N_Pragma then
2766 Spec_Id := Defining_Entity (Subp_Decl);
2767 Set_Corresponding_Spec (N, Spec_Id);
2769 -- Mark the generated spec as a source construct to ensure that all
2770 -- calls to it are properly registered in ALI files for GNATprove.
2772 Set_Comes_From_Source (Spec_Id, True);
2774 -- Ensure that the specs of the subprogram declaration and its body
2775 -- are identical, otherwise they will appear non-conformant due to
2776 -- rewritings in the default values of formal parameters.
2778 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2779 Set_Specification (N, Body_Spec);
2780 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2781 end Build_Subprogram_Declaration;
2783 ----------------------------
2784 -- Check_Anonymous_Return --
2785 ----------------------------
2787 procedure Check_Anonymous_Return is
2793 if Present (Spec_Id) then
2799 if Ekind (Scop) = E_Function
2800 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2801 and then not Is_Thunk (Scop)
2803 -- Skip internally built functions which handle the case of
2804 -- a null access (see Expand_Interface_Conversion)
2806 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2807 and then not Comes_From_Source (Parent (Scop)))
2809 and then (Has_Task (Designated_Type (Etype (Scop)))
2811 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2813 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2814 and then Expander_Active
2816 -- Avoid cases with no tasking support
2818 and then RTE_Available (RE_Current_Master)
2819 and then not Restriction_Active (No_Task_Hierarchy)
2822 Make_Object_Declaration (Loc,
2823 Defining_Identifier =>
2824 Make_Defining_Identifier (Loc, Name_uMaster),
2825 Constant_Present => True,
2826 Object_Definition =>
2827 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2829 Make_Explicit_Dereference (Loc,
2830 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2832 if Present (Declarations (N)) then
2833 Prepend (Decl, Declarations (N));
2835 Set_Declarations (N, New_List (Decl));
2838 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2839 Set_Has_Master_Entity (Scop);
2841 -- Now mark the containing scope as a task master
2844 while Nkind (Par) /= N_Compilation_Unit loop
2845 Par := Parent (Par);
2846 pragma Assert (Present (Par));
2848 -- If we fall off the top, we are at the outer level, and
2849 -- the environment task is our effective master, so nothing
2853 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2855 Set_Is_Task_Master (Par, True);
2860 end Check_Anonymous_Return;
2862 -------------------------
2863 -- Check_Inline_Pragma --
2864 -------------------------
2866 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2870 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2871 -- True when N is a pragma Inline or Inline_Always that applies
2872 -- to this subprogram.
2874 -----------------------
2875 -- Is_Inline_Pragma --
2876 -----------------------
2878 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2880 if Nkind (N) = N_Pragma
2882 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2883 or else (Pragma_Name_Unmapped (N) = Name_Inline
2885 (Front_End_Inlining or else Optimization_Level > 0)))
2886 and then Present (Pragma_Argument_Associations (N))
2889 Pragma_Arg : Node_Id :=
2890 Expression (First (Pragma_Argument_Associations (N)));
2892 if Nkind (Pragma_Arg) = N_Selected_Component then
2893 Pragma_Arg := Selector_Name (Pragma_Arg);
2896 return Chars (Pragma_Arg) = Chars (Body_Id);
2902 end Is_Inline_Pragma;
2904 -- Start of processing for Check_Inline_Pragma
2907 if not Expander_Active then
2911 if Is_List_Member (N)
2912 and then Present (Next (N))
2913 and then Is_Inline_Pragma (Next (N))
2917 elsif Nkind (N) /= N_Subprogram_Body_Stub
2918 and then Present (Declarations (N))
2919 and then Is_Inline_Pragma (First (Declarations (N)))
2921 Prag := First (Declarations (N));
2927 if Present (Prag) then
2928 if Present (Spec_Id) then
2929 if Is_List_Member (N)
2930 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2931 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2937 -- Create a subprogram declaration, to make treatment uniform.
2938 -- Make the sloc of the subprogram name that of the entity in
2939 -- the body, so that style checks find identical strings.
2942 Subp : constant Entity_Id :=
2943 Make_Defining_Identifier
2944 (Sloc (Body_Id), Chars (Body_Id));
2945 Decl : constant Node_Id :=
2946 Make_Subprogram_Declaration (Loc,
2948 New_Copy_Tree (Specification (N)));
2951 -- Link the body and the generated spec
2953 Set_Corresponding_Body (Decl, Body_Id);
2954 Set_Corresponding_Spec (N, Subp);
2956 Set_Defining_Unit_Name (Specification (Decl), Subp);
2958 -- To ensure proper coverage when body is inlined, indicate
2959 -- whether the subprogram comes from source.
2961 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2963 if Present (First_Formal (Body_Id)) then
2964 Plist := Copy_Parameter_List (Body_Id);
2965 Set_Parameter_Specifications
2966 (Specification (Decl), Plist);
2969 -- Move aspects to the new spec
2971 if Has_Aspects (N) then
2972 Move_Aspects (N, To => Decl);
2975 Insert_Before (N, Decl);
2978 Set_Has_Pragma_Inline (Subp);
2980 if Pragma_Name (Prag) = Name_Inline_Always then
2981 Set_Is_Inlined (Subp);
2982 Set_Has_Pragma_Inline_Always (Subp);
2985 -- Prior to copying the subprogram body to create a template
2986 -- for it for subsequent inlining, remove the pragma from
2987 -- the current body so that the copy that will produce the
2988 -- new body will start from a completely unanalyzed tree.
2990 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2991 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2998 end Check_Inline_Pragma;
3000 --------------------------
3001 -- Check_Missing_Return --
3002 --------------------------
3004 procedure Check_Missing_Return is
3006 Missing_Ret : Boolean;
3009 if Nkind (Body_Spec) = N_Function_Specification then
3010 if Present (Spec_Id) then
3016 if Return_Present (Id) then
3017 Check_Returns (HSS, 'F', Missing_Ret);
3020 Set_Has_Missing_Return (Id);
3023 -- Within a premature instantiation of a package with no body, we
3024 -- build completions of the functions therein, with a Raise
3025 -- statement. No point in complaining about a missing return in
3028 elsif Ekind (Id) = E_Function
3029 and then In_Instance
3030 and then Present (Statements (HSS))
3031 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3035 elsif Is_Generic_Subprogram (Id)
3036 or else not Is_Machine_Code_Subprogram (Id)
3038 Error_Msg_N ("missing RETURN statement in function body", N);
3041 -- If procedure with No_Return, check returns
3043 elsif Nkind (Body_Spec) = N_Procedure_Specification
3044 and then Present (Spec_Id)
3045 and then No_Return (Spec_Id)
3047 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
3050 -- Special checks in SPARK mode
3052 if Nkind (Body_Spec) = N_Function_Specification then
3054 -- In SPARK mode, last statement of a function should be a return
3057 Stat : constant Node_Id := Last_Source_Statement (HSS);
3060 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3061 N_Extended_Return_Statement)
3063 Check_SPARK_05_Restriction
3064 ("last statement in function should be RETURN", Stat);
3068 -- In SPARK mode, verify that a procedure has no return
3070 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3071 if Present (Spec_Id) then
3077 -- Would be nice to point to return statement here, can we
3078 -- borrow the Check_Returns procedure here ???
3080 if Return_Present (Id) then
3081 Check_SPARK_05_Restriction
3082 ("procedure should not have RETURN", N);
3085 end Check_Missing_Return;
3087 -----------------------
3088 -- Disambiguate_Spec --
3089 -----------------------
3091 function Disambiguate_Spec return Entity_Id is
3092 Priv_Spec : Entity_Id;
3095 procedure Replace_Types (To_Corresponding : Boolean);
3096 -- Depending on the flag, replace the type of formal parameters of
3097 -- Body_Id if it is a concurrent type implementing interfaces with
3098 -- the corresponding record type or the other way around.
3100 procedure Replace_Types (To_Corresponding : Boolean) is
3102 Formal_Typ : Entity_Id;
3105 Formal := First_Formal (Body_Id);
3106 while Present (Formal) loop
3107 Formal_Typ := Etype (Formal);
3109 if Is_Class_Wide_Type (Formal_Typ) then
3110 Formal_Typ := Root_Type (Formal_Typ);
3113 -- From concurrent type to corresponding record
3115 if To_Corresponding then
3116 if Is_Concurrent_Type (Formal_Typ)
3117 and then Present (Corresponding_Record_Type (Formal_Typ))
3120 (Corresponding_Record_Type (Formal_Typ)))
3123 Corresponding_Record_Type (Formal_Typ));
3126 -- From corresponding record to concurrent type
3129 if Is_Concurrent_Record_Type (Formal_Typ)
3130 and then Present (Interfaces (Formal_Typ))
3133 Corresponding_Concurrent_Type (Formal_Typ));
3137 Next_Formal (Formal);
3141 -- Start of processing for Disambiguate_Spec
3144 -- Try to retrieve the specification of the body as is. All error
3145 -- messages are suppressed because the body may not have a spec in
3146 -- its current state.
3148 Spec_N := Find_Corresponding_Spec (N, False);
3150 -- It is possible that this is the body of a primitive declared
3151 -- between a private and a full view of a concurrent type. The
3152 -- controlling parameter of the spec carries the concurrent type,
3153 -- not the corresponding record type as transformed by Analyze_
3154 -- Subprogram_Specification. In such cases, we undo the change
3155 -- made by the analysis of the specification and try to find the
3158 -- Note that wrappers already have their corresponding specs and
3159 -- bodies set during their creation, so if the candidate spec is
3160 -- a wrapper, then we definitely need to swap all types to their
3161 -- original concurrent status.
3164 or else Is_Primitive_Wrapper (Spec_N)
3166 -- Restore all references of corresponding record types to the
3167 -- original concurrent types.
3169 Replace_Types (To_Corresponding => False);
3170 Priv_Spec := Find_Corresponding_Spec (N, False);
3172 -- The current body truly belongs to a primitive declared between
3173 -- a private and a full view. We leave the modified body as is,
3174 -- and return the true spec.
3176 if Present (Priv_Spec)
3177 and then Is_Private_Primitive (Priv_Spec)
3182 -- In case that this is some sort of error, restore the original
3183 -- state of the body.
3185 Replace_Types (To_Corresponding => True);
3189 end Disambiguate_Spec;
3191 ----------------------------
3192 -- Exchange_Limited_Views --
3193 ----------------------------
3195 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3196 Result : Elist_Id := No_Elist;
3198 procedure Detect_And_Exchange (Id : Entity_Id);
3199 -- Determine whether Id's type denotes an incomplete type associated
3200 -- with a limited with clause and exchange the limited view with the
3201 -- non-limited one when available. Note that the non-limited view
3202 -- may exist because of a with_clause in another unit in the context,
3203 -- but cannot be used because the current view of the enclosing unit
3204 -- is still a limited view.
3206 -------------------------
3207 -- Detect_And_Exchange --
3208 -------------------------
3210 procedure Detect_And_Exchange (Id : Entity_Id) is
3211 Typ : constant Entity_Id := Etype (Id);
3213 if From_Limited_With (Typ)
3214 and then Has_Non_Limited_View (Typ)
3215 and then not From_Limited_With (Scope (Typ))
3218 Result := New_Elmt_List;
3221 Prepend_Elmt (Typ, Result);
3222 Prepend_Elmt (Id, Result);
3223 Set_Etype (Id, Non_Limited_View (Typ));
3225 end Detect_And_Exchange;
3231 -- Start of processing for Exchange_Limited_Views
3234 -- Do not process subprogram bodies as they already use the non-
3235 -- limited view of types.
3237 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3241 -- Examine all formals and swap views when applicable
3243 Formal := First_Formal (Subp_Id);
3244 while Present (Formal) loop
3245 Detect_And_Exchange (Formal);
3247 Next_Formal (Formal);
3250 -- Process the return type of a function
3252 if Ekind (Subp_Id) = E_Function then
3253 Detect_And_Exchange (Subp_Id);
3257 end Exchange_Limited_Views;
3259 -------------------------------------
3260 -- Is_Private_Concurrent_Primitive --
3261 -------------------------------------
3263 function Is_Private_Concurrent_Primitive
3264 (Subp_Id : Entity_Id) return Boolean
3266 Formal_Typ : Entity_Id;
3269 if Present (First_Formal (Subp_Id)) then
3270 Formal_Typ := Etype (First_Formal (Subp_Id));
3272 if Is_Concurrent_Record_Type (Formal_Typ) then
3273 if Is_Class_Wide_Type (Formal_Typ) then
3274 Formal_Typ := Root_Type (Formal_Typ);
3277 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3280 -- The type of the first formal is a concurrent tagged type with
3284 Is_Concurrent_Type (Formal_Typ)
3285 and then Is_Tagged_Type (Formal_Typ)
3286 and then Has_Private_Declaration (Formal_Typ);
3290 end Is_Private_Concurrent_Primitive;
3292 -------------------------
3293 -- Mask_Unfrozen_Types --
3294 -------------------------
3296 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3297 Result : Elist_Id := No_Elist;
3299 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3300 -- Mask all types referenced in the subtree rooted at Node
3302 --------------------
3303 -- Mask_Type_Refs --
3304 --------------------
3306 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3307 procedure Mask_Type (Typ : Entity_Id);
3308 -- ??? what does this do?
3314 procedure Mask_Type (Typ : Entity_Id) is
3316 -- Skip Itypes created by the preanalysis
3319 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3324 if not Is_Frozen (Typ) then
3325 Set_Is_Frozen (Typ);
3326 Append_New_Elmt (Typ, Result);
3330 -- Start of processing for Mask_Type_Refs
3333 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3334 Mask_Type (Etype (Entity (Node)));
3336 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3337 Mask_Type (Scope (Entity (Node)));
3340 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3341 and then Present (Etype (Node))
3343 Mask_Type (Etype (Node));
3349 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3353 Return_Stmt : constant Node_Id :=
3354 First (Statements (Handled_Statement_Sequence (N)));
3356 -- Start of processing for Mask_Unfrozen_Types
3359 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3361 Mask_References (Expression (Return_Stmt));
3364 end Mask_Unfrozen_Types;
3366 ---------------------------
3367 -- Restore_Limited_Views --
3368 ---------------------------
3370 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3371 Elmt : Elmt_Id := First_Elmt (Restore_List);
3375 while Present (Elmt) loop
3378 Set_Etype (Id, Node (Elmt));
3381 end Restore_Limited_Views;
3383 ----------------------------
3384 -- Set_Trivial_Subprogram --
3385 ----------------------------
3387 procedure Set_Trivial_Subprogram (N : Node_Id) is
3388 Nxt : constant Node_Id := Next (N);
3391 Set_Is_Trivial_Subprogram (Body_Id);
3393 if Present (Spec_Id) then
3394 Set_Is_Trivial_Subprogram (Spec_Id);
3398 and then Nkind (Nxt) = N_Simple_Return_Statement
3399 and then No (Next (Nxt))
3400 and then Present (Expression (Nxt))
3401 and then Is_Entity_Name (Expression (Nxt))
3403 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3405 end Set_Trivial_Subprogram;
3407 ---------------------------
3408 -- Unmask_Unfrozen_Types --
3409 ---------------------------
3411 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3412 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3415 while Present (Elmt) loop
3416 Set_Is_Frozen (Node (Elmt), False);
3419 end Unmask_Unfrozen_Types;
3421 ---------------------------------
3422 -- Verify_Overriding_Indicator --
3423 ---------------------------------
3425 procedure Verify_Overriding_Indicator is
3427 if Must_Override (Body_Spec) then
3428 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3429 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3433 elsif not Present (Overridden_Operation (Spec_Id)) then
3435 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3437 -- Overriding indicators aren't allowed for protected subprogram
3438 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3439 -- this to a warning if -gnatd.E is enabled.
3441 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3442 Error_Msg_Warn := Error_To_Warning;
3444 ("<<overriding indicator not allowed for protected "
3445 & "subprogram body", Body_Spec);
3448 elsif Must_Not_Override (Body_Spec) then
3449 if Present (Overridden_Operation (Spec_Id)) then
3451 ("subprogram& overrides inherited operation",
3452 Body_Spec, Spec_Id);
3454 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3455 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3458 ("subprogram& overrides predefined operator ",
3459 Body_Spec, Spec_Id);
3461 -- Overriding indicators aren't allowed for protected subprogram
3462 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3463 -- this to a warning if -gnatd.E is enabled.
3465 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3466 Error_Msg_Warn := Error_To_Warning;
3469 ("<<overriding indicator not allowed "
3470 & "for protected subprogram body", Body_Spec);
3472 -- If this is not a primitive operation, then the overriding
3473 -- indicator is altogether illegal.
3475 elsif not Is_Primitive (Spec_Id) then
3477 ("overriding indicator only allowed "
3478 & "if subprogram is primitive", Body_Spec);
3481 -- If checking the style rule and the operation overrides, then
3482 -- issue a warning about a missing overriding_indicator. Protected
3483 -- subprogram bodies are excluded from this style checking, since
3484 -- they aren't primitives (even though their declarations can
3485 -- override) and aren't allowed to have an overriding_indicator.
3488 and then Present (Overridden_Operation (Spec_Id))
3489 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3491 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3492 Style.Missing_Overriding (N, Body_Id);
3495 and then Can_Override_Operator (Spec_Id)
3496 and then not In_Predefined_Unit (Spec_Id)
3498 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3499 Style.Missing_Overriding (N, Body_Id);
3501 end Verify_Overriding_Indicator;
3505 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3506 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3507 Saved_ISMP : constant Boolean :=
3508 Ignore_SPARK_Mode_Pragmas_In_Instance;
3509 -- Save the Ghost and SPARK mode-related data to restore on exit
3511 -- Start of processing for Analyze_Subprogram_Body_Helper
3514 -- A [generic] subprogram body freezes the contract of the nearest
3515 -- enclosing package body and all other contracts encountered in the
3516 -- same declarative part up to and excluding the subprogram body:
3518 -- package body Nearest_Enclosing_Package
3519 -- with Refined_State => (State => Constit)
3523 -- procedure Freezes_Enclosing_Package_Body
3524 -- with Refined_Depends => (Input => Constit) ...
3526 -- This ensures that any annotations referenced by the contract of the
3527 -- [generic] subprogram body are available. This form of freezing is
3528 -- decoupled from the usual Freeze_xxx mechanism because it must also
3529 -- work in the context of generics where normal freezing is disabled.
3531 -- Only bodies coming from source should cause this type of freezing.
3532 -- Expression functions that act as bodies and complete an initial
3533 -- declaration must be included in this category, hence the use of
3536 if Comes_From_Source (Original_Node (N)) then
3537 Freeze_Previous_Contracts (N);
3540 -- Generic subprograms are handled separately. They always have a
3541 -- generic specification. Determine whether current scope has a
3542 -- previous declaration.
3544 -- If the subprogram body is defined within an instance of the same
3545 -- name, the instance appears as a package renaming, and will be hidden
3546 -- within the subprogram.
3548 if Present (Prev_Id)
3549 and then not Is_Overloadable (Prev_Id)
3550 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3551 or else Comes_From_Source (Prev_Id))
3553 if Is_Generic_Subprogram (Prev_Id) then
3556 -- A subprogram body is Ghost when it is stand alone and subject
3557 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3558 -- the mode now to ensure that any nodes generated during analysis
3559 -- and expansion are properly marked as Ghost.
3561 Mark_And_Set_Ghost_Body (N, Spec_Id);
3563 -- If the body completes the initial declaration of a compilation
3564 -- unit which is subject to pragma Elaboration_Checks, set the
3565 -- model specified by the pragma because it applies to all parts
3568 Install_Elaboration_Model (Spec_Id);
3570 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3571 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3573 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3575 if Nkind (N) = N_Subprogram_Body then
3576 HSS := Handled_Statement_Sequence (N);
3577 Check_Missing_Return;
3582 -- Otherwise a previous entity conflicts with the subprogram name.
3583 -- Attempting to enter name will post error.
3586 Enter_Name (Body_Id);
3590 -- Non-generic case, find the subprogram declaration, if one was seen,
3591 -- or enter new overloaded entity in the current scope. If the
3592 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3593 -- part of the context of one of its subunits. No need to redo the
3596 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3600 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3602 if Nkind (N) = N_Subprogram_Body_Stub
3603 or else No (Corresponding_Spec (N))
3605 if Is_Private_Concurrent_Primitive (Body_Id) then
3606 Spec_Id := Disambiguate_Spec;
3608 -- A subprogram body is Ghost when it is stand alone and
3609 -- subject to pragma Ghost or when the corresponding spec is
3610 -- Ghost. Set the mode now to ensure that any nodes generated
3611 -- during analysis and expansion are properly marked as Ghost.
3613 Mark_And_Set_Ghost_Body (N, Spec_Id);
3615 -- If the body completes a compilation unit which is subject
3616 -- to pragma Elaboration_Checks, set the model specified by
3617 -- the pragma because it applies to all parts of the unit.
3619 Install_Elaboration_Model (Spec_Id);
3622 Spec_Id := Find_Corresponding_Spec (N);
3624 -- A subprogram body is Ghost when it is stand alone and
3625 -- subject to pragma Ghost or when the corresponding spec is
3626 -- Ghost. Set the mode now to ensure that any nodes generated
3627 -- during analysis and expansion are properly marked as Ghost.
3629 Mark_And_Set_Ghost_Body (N, Spec_Id);
3631 -- If the body completes a compilation unit which is subject
3632 -- to pragma Elaboration_Checks, set the model specified by
3633 -- the pragma because it applies to all parts of the unit.
3635 Install_Elaboration_Model (Spec_Id);
3637 -- In GNATprove mode, if the body has no previous spec, create
3638 -- one so that the inlining machinery can operate properly.
3639 -- Transfer aspects, if any, to the new spec, so that they
3640 -- are legal and can be processed ahead of the body.
3641 -- We make two copies of the given spec, one for the new
3642 -- declaration, and one for the body.
3644 if No (Spec_Id) and then GNATprove_Mode
3646 -- Inlining does not apply during pre-analysis of code
3648 and then Full_Analysis
3650 -- Inlining only applies to full bodies, not stubs
3652 and then Nkind (N) /= N_Subprogram_Body_Stub
3654 -- Inlining only applies to bodies in the source code, not to
3655 -- those generated by the compiler. In particular, expression
3656 -- functions, whose body is generated by the compiler, are
3657 -- treated specially by GNATprove.
3659 and then Comes_From_Source (Body_Id)
3661 -- This cannot be done for a compilation unit, which is not
3662 -- in a context where we can insert a new spec.
3664 and then Is_List_Member (N)
3666 -- Inlining only applies to subprograms without contracts,
3667 -- as a contract is a sign that GNATprove should perform a
3668 -- modular analysis of the subprogram instead of a contextual
3669 -- analysis at each call site. The same test is performed in
3670 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3671 -- here in another form (because the contract has not been
3672 -- attached to the body) to avoid front-end errors in case
3673 -- pragmas are used instead of aspects, because the
3674 -- corresponding pragmas in the body would not be transferred
3675 -- to the spec, leading to legality errors.
3677 and then not Body_Has_Contract
3678 and then not Inside_A_Generic
3680 Build_Subprogram_Declaration;
3682 -- If this is a function that returns a constrained array, and
3683 -- we are generating SPARK_For_C, create subprogram declaration
3684 -- to simplify subsequent C generation.
3687 and then Modify_Tree_For_C
3688 and then Nkind (Body_Spec) = N_Function_Specification
3689 and then Is_Array_Type (Etype (Body_Id))
3690 and then Is_Constrained (Etype (Body_Id))
3692 Build_Subprogram_Declaration;
3696 -- If this is a duplicate body, no point in analyzing it
3698 if Error_Posted (N) then
3702 -- A subprogram body should cause freezing of its own declaration,
3703 -- but if there was no previous explicit declaration, then the
3704 -- subprogram will get frozen too late (there may be code within
3705 -- the body that depends on the subprogram having been frozen,
3706 -- such as uses of extra formals), so we force it to be frozen
3707 -- here. Same holds if the body and spec are compilation units.
3708 -- Finally, if the return type is an anonymous access to protected
3709 -- subprogram, it must be frozen before the body because its
3710 -- expansion has generated an equivalent type that is used when
3711 -- elaborating the body.
3713 -- An exception in the case of Ada 2012, AI05-177: The bodies
3714 -- created for expression functions do not freeze.
3717 and then Nkind (Original_Node (N)) /= N_Expression_Function
3719 Freeze_Before (N, Body_Id);
3721 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3722 Freeze_Before (N, Spec_Id);
3724 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3725 Freeze_Before (N, Etype (Body_Id));
3729 Spec_Id := Corresponding_Spec (N);
3731 -- A subprogram body is Ghost when it is stand alone and subject
3732 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3733 -- the mode now to ensure that any nodes generated during analysis
3734 -- and expansion are properly marked as Ghost.
3736 Mark_And_Set_Ghost_Body (N, Spec_Id);
3738 -- If the body completes the initial declaration of a compilation
3739 -- unit which is subject to pragma Elaboration_Checks, set the
3740 -- model specified by the pragma because it applies to all parts
3743 Install_Elaboration_Model (Spec_Id);
3747 -- Previously we scanned the body to look for nested subprograms, and
3748 -- rejected an inline directive if nested subprograms were present,
3749 -- because the back-end would generate conflicting symbols for the
3750 -- nested bodies. This is now unnecessary.
3752 -- Look ahead to recognize a pragma Inline that appears after the body
3754 Check_Inline_Pragma (Spec_Id);
3756 -- Deal with special case of a fully private operation in the body of
3757 -- the protected type. We must create a declaration for the subprogram,
3758 -- in order to attach the protected subprogram that will be used in
3759 -- internal calls. We exclude compiler generated bodies from the
3760 -- expander since the issue does not arise for those cases.
3763 and then Comes_From_Source (N)
3764 and then Is_Protected_Type (Current_Scope)
3766 Spec_Id := Build_Private_Protected_Declaration (N);
3769 -- If we are generating C and this is a function returning a constrained
3770 -- array type for which we must create a procedure with an extra out
3771 -- parameter, build and analyze the body now. The procedure declaration
3772 -- has already been created. We reuse the source body of the function,
3773 -- because in an instance it may contain global references that cannot
3774 -- be reanalyzed. The source function itself is not used any further,
3775 -- so we mark it as having a completion. If the subprogram is a stub the
3776 -- transformation is done later, when the proper body is analyzed.
3779 and then Modify_Tree_For_C
3780 and then Present (Spec_Id)
3781 and then Ekind (Spec_Id) = E_Function
3782 and then Nkind (N) /= N_Subprogram_Body_Stub
3783 and then Rewritten_For_C (Spec_Id)
3785 Set_Has_Completion (Spec_Id);
3787 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3790 -- The entity for the created procedure must remain invisible, so it
3791 -- does not participate in resolution of subsequent references to the
3794 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3798 -- If a separate spec is present, then deal with freezing issues
3800 if Present (Spec_Id) then
3801 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3802 Verify_Overriding_Indicator;
3804 -- In general, the spec will be frozen when we start analyzing the
3805 -- body. However, for internally generated operations, such as
3806 -- wrapper functions for inherited operations with controlling
3807 -- results, the spec may not have been frozen by the time we expand
3808 -- the freeze actions that include the bodies. In particular, extra
3809 -- formals for accessibility or for return-in-place may need to be
3810 -- generated. Freeze nodes, if any, are inserted before the current
3811 -- body. These freeze actions are also needed in ASIS mode and in
3812 -- Compile_Only mode to enable the proper back-end type annotations.
3813 -- They are necessary in any case to insure order of elaboration
3816 if not Is_Frozen (Spec_Id)
3817 and then (Expander_Active
3819 or else (Operating_Mode = Check_Semantics
3820 and then Serious_Errors_Detected = 0))
3822 -- The body generated for an expression function that is not a
3823 -- completion is a freeze point neither for the profile nor for
3824 -- anything else. That's why, in order to prevent any freezing
3825 -- during analysis, we need to mask types declared outside the
3826 -- expression that are not yet frozen.
3828 if Nkind (N) = N_Subprogram_Body
3829 and then Was_Expression_Function (N)
3830 and then not Has_Completion (Spec_Id)
3832 Set_Is_Frozen (Spec_Id);
3833 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3835 Set_Has_Delayed_Freeze (Spec_Id);
3836 Freeze_Before (N, Spec_Id);
3841 -- If the subprogram has a class-wide clone, build its body as a copy
3842 -- of the original body, and rewrite body of original subprogram as a
3843 -- wrapper that calls the clone. If N is a stub, this construction will
3844 -- take place when the proper body is analyzed.
3846 if Present (Spec_Id)
3847 and then Present (Class_Wide_Clone (Spec_Id))
3848 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3849 and then Nkind (N) /= N_Subprogram_Body_Stub
3851 Build_Class_Wide_Clone_Body (Spec_Id, N);
3853 -- This is the new body for the existing primitive operation
3855 Rewrite (N, Build_Class_Wide_Clone_Call
3856 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3857 Set_Has_Completion (Spec_Id, False);
3862 -- Place subprogram on scope stack, and make formals visible. If there
3863 -- is a spec, the visible entity remains that of the spec.
3865 if Present (Spec_Id) then
3866 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3868 if Is_Child_Unit (Spec_Id) then
3869 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3873 Style.Check_Identifier (Body_Id, Spec_Id);
3876 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3877 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3879 if Is_Abstract_Subprogram (Spec_Id) then
3880 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3884 Set_Convention (Body_Id, Convention (Spec_Id));
3885 Set_Has_Completion (Spec_Id);
3887 if Is_Protected_Type (Scope (Spec_Id)) then
3888 Prot_Typ := Scope (Spec_Id);
3891 -- If this is a body generated for a renaming, do not check for
3892 -- full conformance. The check is redundant, because the spec of
3893 -- the body is a copy of the spec in the renaming declaration,
3894 -- and the test can lead to spurious errors on nested defaults.
3896 if Present (Spec_Decl)
3897 and then not Comes_From_Source (N)
3899 (Nkind (Original_Node (Spec_Decl)) =
3900 N_Subprogram_Renaming_Declaration
3901 or else (Present (Corresponding_Body (Spec_Decl))
3903 Nkind (Unit_Declaration_Node
3904 (Corresponding_Body (Spec_Decl))) =
3905 N_Subprogram_Renaming_Declaration))
3909 -- Conversely, the spec may have been generated for specless body
3910 -- with an inline pragma. The entity comes from source, which is
3911 -- both semantically correct and necessary for proper inlining.
3912 -- The subprogram declaration itself is not in the source.
3914 elsif Comes_From_Source (N)
3915 and then Present (Spec_Decl)
3916 and then not Comes_From_Source (Spec_Decl)
3917 and then Has_Pragma_Inline (Spec_Id)
3924 Fully_Conformant, True, Conformant, Body_Id);
3927 -- If the body is not fully conformant, we have to decide if we
3928 -- should analyze it or not. If it has a really messed up profile
3929 -- then we probably should not analyze it, since we will get too
3930 -- many bogus messages.
3932 -- Our decision is to go ahead in the non-fully conformant case
3933 -- only if it is at least mode conformant with the spec. Note
3934 -- that the call to Check_Fully_Conformant has issued the proper
3935 -- error messages to complain about the lack of conformance.
3938 and then not Mode_Conformant (Body_Id, Spec_Id)
3944 -- In the case we are dealing with an expression function we check
3945 -- the formals attached to the spec instead of the body - so we don't
3946 -- reference body formals.
3948 if Spec_Id /= Body_Id
3949 and then not Is_Expression_Function (Spec_Id)
3951 Reference_Body_Formals (Spec_Id, Body_Id);
3954 Set_Ekind (Body_Id, E_Subprogram_Body);
3956 if Nkind (N) = N_Subprogram_Body_Stub then
3957 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3962 Set_Corresponding_Spec (N, Spec_Id);
3964 -- Ada 2005 (AI-345): If the operation is a primitive operation
3965 -- of a concurrent type, the type of the first parameter has been
3966 -- replaced with the corresponding record, which is the proper
3967 -- run-time structure to use. However, within the body there may
3968 -- be uses of the formals that depend on primitive operations
3969 -- of the type (in particular calls in prefixed form) for which
3970 -- we need the original concurrent type. The operation may have
3971 -- several controlling formals, so the replacement must be done
3974 if Comes_From_Source (Spec_Id)
3975 and then Present (First_Entity (Spec_Id))
3976 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3977 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3978 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3979 and then Present (Corresponding_Concurrent_Type
3980 (Etype (First_Entity (Spec_Id))))
3983 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3987 Form := First_Formal (Spec_Id);
3988 while Present (Form) loop
3989 if Etype (Form) = Typ then
3990 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3998 -- Make the formals visible, and place subprogram on scope stack.
3999 -- This is also the point at which we set Last_Real_Spec_Entity
4000 -- to mark the entities which will not be moved to the body.
4002 Install_Formals (Spec_Id);
4003 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
4005 -- Within an instance, add local renaming declarations so that
4006 -- gdb can retrieve the values of actuals more easily. This is
4007 -- only relevant if generating code (and indeed we definitely
4008 -- do not want these definitions -gnatc mode, because that would
4011 if Is_Generic_Instance (Spec_Id)
4012 and then Is_Wrapper_Package (Current_Scope)
4013 and then Expander_Active
4015 Build_Subprogram_Instance_Renamings (N, Current_Scope);
4018 Push_Scope (Spec_Id);
4020 -- Make sure that the subprogram is immediately visible. For
4021 -- child units that have no separate spec this is indispensable.
4022 -- Otherwise it is safe albeit redundant.
4024 Set_Is_Immediately_Visible (Spec_Id);
4027 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
4028 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
4029 Set_Scope (Body_Id, Scope (Spec_Id));
4031 -- Case of subprogram body with no previous spec
4034 -- Check for style warning required
4038 -- Only apply check for source level subprograms for which checks
4039 -- have not been suppressed.
4041 and then Comes_From_Source (Body_Id)
4042 and then not Suppress_Style_Checks (Body_Id)
4044 -- No warnings within an instance
4046 and then not In_Instance
4048 -- No warnings for expression functions
4050 and then Nkind (Original_Node (N)) /= N_Expression_Function
4052 Style.Body_With_No_Spec (N);
4055 New_Overloaded_Entity (Body_Id);
4057 if Nkind (N) /= N_Subprogram_Body_Stub then
4058 Set_Acts_As_Spec (N);
4059 Generate_Definition (Body_Id);
4061 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
4063 -- If the body is an entry wrapper created for an entry with
4064 -- preconditions, it must be compiled in the context of the
4065 -- enclosing synchronized object, because it may mention other
4066 -- operations of the type.
4068 if Is_Entry_Wrapper (Body_Id) then
4070 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4073 Install_Declarations (Prot);
4077 Install_Formals (Body_Id);
4079 Push_Scope (Body_Id);
4082 -- For stubs and bodies with no previous spec, generate references to
4085 Generate_Reference_To_Formals (Body_Id);
4088 -- Entry barrier functions are generated outside the protected type and
4089 -- should not carry the SPARK_Mode of the enclosing context.
4091 if Nkind (N) = N_Subprogram_Body
4092 and then Is_Entry_Barrier_Function (N)
4096 -- The body is generated as part of expression function expansion. When
4097 -- the expression function appears in the visible declarations of a
4098 -- package, the body is added to the private declarations. Since both
4099 -- declarative lists may be subject to a different SPARK_Mode, inherit
4100 -- the mode of the spec.
4102 -- package P with SPARK_Mode is
4103 -- function Expr_Func ... is (...); -- original
4104 -- [function Expr_Func ...;] -- generated spec
4107 -- pragma SPARK_Mode (Off);
4108 -- [function Expr_Func ... is return ...;] -- generated body
4109 -- end P; -- mode is ON
4111 elsif not Comes_From_Source (N)
4112 and then Present (Spec_Id)
4113 and then Is_Expression_Function (Spec_Id)
4115 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4116 Set_SPARK_Pragma_Inherited
4117 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4119 -- Set the SPARK_Mode from the current context (may be overwritten later
4120 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4121 -- initially on a stand-alone subprogram body, but is then relocated to
4122 -- a generated corresponding spec. In this scenario the mode is shared
4123 -- between the spec and body.
4125 elsif No (SPARK_Pragma (Body_Id)) then
4126 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4127 Set_SPARK_Pragma_Inherited (Body_Id);
4130 -- A subprogram body may be instantiated or inlined at a later pass.
4131 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4132 -- applied to the initial declaration of the body.
4134 if Present (Spec_Id) then
4135 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4136 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4140 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4141 -- case the body is instantiated or inlined later and out of context.
4142 -- The body uses this attribute to restore the value of the global
4145 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4146 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4148 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4149 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4153 -- Preserve relevant elaboration-related attributes of the context which
4154 -- are no longer available or very expensive to recompute once analysis,
4155 -- resolution, and expansion are over.
4157 if No (Spec_Id) then
4158 Mark_Elaboration_Attributes
4164 -- If this is the proper body of a stub, we must verify that the stub
4165 -- conforms to the body, and to the previous spec if one was present.
4166 -- We know already that the body conforms to that spec. This test is
4167 -- only required for subprograms that come from source.
4169 if Nkind (Parent (N)) = N_Subunit
4170 and then Comes_From_Source (N)
4171 and then not Error_Posted (Body_Id)
4172 and then Nkind (Corresponding_Stub (Parent (N))) =
4173 N_Subprogram_Body_Stub
4176 Old_Id : constant Entity_Id :=
4178 (Specification (Corresponding_Stub (Parent (N))));
4180 Conformant : Boolean := False;
4183 if No (Spec_Id) then
4184 Check_Fully_Conformant (Body_Id, Old_Id);
4188 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4190 if not Conformant then
4192 -- The stub was taken to be a new declaration. Indicate that
4195 Set_Has_Completion (Old_Id, False);
4201 Set_Has_Completion (Body_Id);
4202 Check_Eliminated (Body_Id);
4204 -- Analyze any aspect specifications that appear on the subprogram body
4205 -- stub. Stop the analysis now as the stub does not have a declarative
4206 -- or a statement part, and it cannot be inlined.
4208 if Nkind (N) = N_Subprogram_Body_Stub then
4209 if Has_Aspects (N) then
4210 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4218 -- Note: Normally we don't do any inlining if expansion is off, since
4219 -- we won't generate code in any case. An exception arises in GNATprove
4220 -- mode where we want to expand some calls in place, even with expansion
4221 -- disabled, since the inlining eases formal verification.
4223 if not GNATprove_Mode
4224 and then Expander_Active
4225 and then Serious_Errors_Detected = 0
4226 and then Present (Spec_Id)
4227 and then Has_Pragma_Inline (Spec_Id)
4229 -- Legacy implementation (relying on front-end inlining)
4231 if not Back_End_Inlining then
4232 if (Has_Pragma_Inline_Always (Spec_Id)
4233 and then not Opt.Disable_FE_Inline_Always)
4234 or else (Front_End_Inlining
4235 and then not Opt.Disable_FE_Inline)
4237 Build_Body_To_Inline (N, Spec_Id);
4240 -- New implementation (relying on back-end inlining)
4243 if Has_Pragma_Inline_Always (Spec_Id)
4244 or else Optimization_Level > 0
4246 -- Handle function returning an unconstrained type
4248 if Comes_From_Source (Body_Id)
4249 and then Ekind (Spec_Id) = E_Function
4250 and then Returns_Unconstrained_Type (Spec_Id)
4252 -- If function builds in place, i.e. returns a limited type,
4253 -- inlining cannot be done.
4255 and then not Is_Limited_Type (Etype (Spec_Id))
4257 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4261 Subp_Body : constant Node_Id :=
4262 Unit_Declaration_Node (Body_Id);
4263 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4266 -- Do not pass inlining to the backend if the subprogram
4267 -- has declarations or statements which cannot be inlined
4268 -- by the backend. This check is done here to emit an
4269 -- error instead of the generic warning message reported
4270 -- by the GCC backend (ie. "function might not be
4273 if Present (Subp_Decl)
4274 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4278 elsif Has_Excluded_Statement
4281 (Handled_Statement_Sequence (Subp_Body)))
4285 -- If the backend inlining is available then at this
4286 -- stage we only have to mark the subprogram as inlined.
4287 -- The expander will take care of registering it in the
4288 -- table of subprograms inlined by the backend a part of
4289 -- processing calls to it (cf. Expand_Call)
4292 Set_Is_Inlined (Spec_Id);
4299 -- In GNATprove mode, inline only when there is a separate subprogram
4300 -- declaration for now, as inlining of subprogram bodies acting as
4301 -- declarations, or subprogram stubs, are not supported by front-end
4302 -- inlining. This inlining should occur after analysis of the body, so
4303 -- that it is known whether the value of SPARK_Mode, which can be
4304 -- defined by a pragma inside the body, is applicable to the body.
4305 -- Inlining can be disabled with switch -gnatdm
4307 elsif GNATprove_Mode
4308 and then Full_Analysis
4309 and then not Inside_A_Generic
4310 and then Present (Spec_Id)
4312 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4313 and then Body_Has_SPARK_Mode_On
4314 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4315 and then not Body_Has_Contract
4316 and then not Debug_Flag_M
4318 Build_Body_To_Inline (N, Spec_Id);
4321 -- When generating code, inherited pre/postconditions are handled when
4322 -- expanding the corresponding contract.
4324 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4325 -- of the specification we have to install the private withed units.
4326 -- This holds for child units as well.
4328 if Is_Compilation_Unit (Body_Id)
4329 or else Nkind (Parent (N)) = N_Compilation_Unit
4331 Install_Private_With_Clauses (Body_Id);
4334 Check_Anonymous_Return;
4336 -- Set the Protected_Formal field of each extra formal of the protected
4337 -- subprogram to reference the corresponding extra formal of the
4338 -- subprogram that implements it. For regular formals this occurs when
4339 -- the protected subprogram's declaration is expanded, but the extra
4340 -- formals don't get created until the subprogram is frozen. We need to
4341 -- do this before analyzing the protected subprogram's body so that any
4342 -- references to the original subprogram's extra formals will be changed
4343 -- refer to the implementing subprogram's formals (see Expand_Formal).
4345 if Present (Spec_Id)
4346 and then Is_Protected_Type (Scope (Spec_Id))
4347 and then Present (Protected_Body_Subprogram (Spec_Id))
4350 Impl_Subp : constant Entity_Id :=
4351 Protected_Body_Subprogram (Spec_Id);
4352 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4353 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4356 while Present (Prot_Ext_Formal) loop
4357 pragma Assert (Present (Impl_Ext_Formal));
4358 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4359 Next_Formal_With_Extras (Prot_Ext_Formal);
4360 Next_Formal_With_Extras (Impl_Ext_Formal);
4365 -- Now we can go on to analyze the body
4367 HSS := Handled_Statement_Sequence (N);
4368 Set_Actual_Subtypes (N, Current_Scope);
4370 -- Add a declaration for the Protection object, renaming declarations
4371 -- for discriminals and privals and finally a declaration for the entry
4372 -- family index (if applicable). This form of early expansion is done
4373 -- when the Expander is active because Install_Private_Data_Declarations
4374 -- references entities which were created during regular expansion. The
4375 -- subprogram entity must come from source, and not be an internally
4376 -- generated subprogram.
4379 and then Present (Prot_Typ)
4380 and then Present (Spec_Id)
4381 and then Comes_From_Source (Spec_Id)
4382 and then not Is_Eliminated (Spec_Id)
4384 Install_Private_Data_Declarations
4385 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4388 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4389 -- may now appear in parameter and result profiles. Since the analysis
4390 -- of a subprogram body may use the parameter and result profile of the
4391 -- spec, swap any limited views with their non-limited counterpart.
4393 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4394 Exch_Views := Exchange_Limited_Views (Spec_Id);
4397 -- If the return type is an anonymous access type whose designated type
4398 -- is the limited view of a class-wide type and the non-limited view is
4399 -- available, update the return type accordingly.
4401 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4407 Rtyp := Etype (Spec_Id);
4409 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4410 Etyp := Directly_Designated_Type (Rtyp);
4412 if Is_Class_Wide_Type (Etyp)
4413 and then From_Limited_With (Etyp)
4416 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4422 -- Analyze any aspect specifications that appear on the subprogram body
4424 if Has_Aspects (N) then
4425 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4428 Analyze_Declarations (Declarations (N));
4430 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4432 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4433 if Present (SPARK_Pragma (Spec_Id)) then
4434 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4436 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4438 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4439 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4440 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4442 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4445 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4449 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4450 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4451 Error_Msg_Sloc := Sloc (Spec_Id);
4453 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4457 -- A subprogram body freezes its own contract. Analyze the contract
4458 -- after the declarations of the body have been processed as pragmas
4459 -- are now chained on the contract of the subprogram body.
4461 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4463 -- Check completion, and analyze the statements
4466 Inspect_Deferred_Constant_Completion (Declarations (N));
4469 -- Deal with end of scope processing for the body
4471 Process_End_Label (HSS, 't', Current_Scope);
4472 Update_Use_Clause_Chain;
4475 -- If we are compiling an entry wrapper, remove the enclosing
4476 -- synchronized object from the stack.
4478 if Is_Entry_Wrapper (Body_Id) then
4482 Check_Subprogram_Order (N);
4483 Set_Analyzed (Body_Id);
4485 -- If we have a separate spec, then the analysis of the declarations
4486 -- caused the entities in the body to be chained to the spec id, but
4487 -- we want them chained to the body id. Only the formal parameters
4488 -- end up chained to the spec id in this case.
4490 if Present (Spec_Id) then
4492 -- We must conform to the categorization of our spec
4494 Validate_Categorization_Dependency (N, Spec_Id);
4496 -- And if this is a child unit, the parent units must conform
4498 if Is_Child_Unit (Spec_Id) then
4499 Validate_Categorization_Dependency
4500 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4503 -- Here is where we move entities from the spec to the body
4505 -- Case where there are entities that stay with the spec
4507 if Present (Last_Real_Spec_Entity) then
4509 -- No body entities (happens when the only real spec entities come
4510 -- from precondition and postcondition pragmas).
4512 if No (Last_Entity (Body_Id)) then
4513 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4515 -- Body entities present (formals), so chain stuff past them
4519 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4522 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4523 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4524 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4526 -- Case where there are no spec entities, in this case there can be
4527 -- no body entities either, so just move everything.
4529 -- If the body is generated for an expression function, it may have
4530 -- been preanalyzed already, if 'access was applied to it.
4533 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4534 N_Expression_Function
4536 pragma Assert (No (Last_Entity (Body_Id)));
4540 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4541 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4542 Set_First_Entity (Spec_Id, Empty);
4543 Set_Last_Entity (Spec_Id, Empty);
4546 -- Otherwise the body does not complete a previous declaration. Check
4547 -- the categorization of the body against the units it withs.
4550 Validate_Categorization_Dependency (N, Body_Id);
4553 Check_Missing_Return;
4555 -- Now we are going to check for variables that are never modified in
4556 -- the body of the procedure. But first we deal with a special case
4557 -- where we want to modify this check. If the body of the subprogram
4558 -- starts with a raise statement or its equivalent, or if the body
4559 -- consists entirely of a null statement, then it is pretty obvious that
4560 -- it is OK to not reference the parameters. For example, this might be
4561 -- the following common idiom for a stubbed function: statement of the
4562 -- procedure raises an exception. In particular this deals with the
4563 -- common idiom of a stubbed function, which appears something like:
4565 -- function F (A : Integer) return Some_Type;
4568 -- raise Program_Error;
4572 -- Here the purpose of X is simply to satisfy the annoying requirement
4573 -- in Ada that there be at least one return, and we certainly do not
4574 -- want to go posting warnings on X that it is not initialized. On
4575 -- the other hand, if X is entirely unreferenced that should still
4578 -- What we do is to detect these cases, and if we find them, flag the
4579 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4580 -- suppress unwanted warnings. For the case of the function stub above
4581 -- we have a special test to set X as apparently assigned to suppress
4588 -- Skip call markers installed by the ABE mechanism, labels, and
4589 -- Push_xxx_Error_Label to find the first real statement.
4591 Stm := First (Statements (HSS));
4592 while Nkind_In (Stm, N_Call_Marker, N_Label)
4593 or else Nkind (Stm) in N_Push_xxx_Label
4598 -- Do the test on the original statement before expansion
4601 Ostm : constant Node_Id := Original_Node (Stm);
4604 -- If explicit raise statement, turn on flag
4606 if Nkind (Ostm) = N_Raise_Statement then
4607 Set_Trivial_Subprogram (Stm);
4609 -- If null statement, and no following statements, turn on flag
4611 elsif Nkind (Stm) = N_Null_Statement
4612 and then Comes_From_Source (Stm)
4613 and then No (Next (Stm))
4615 Set_Trivial_Subprogram (Stm);
4617 -- Check for explicit call cases which likely raise an exception
4619 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4620 if Is_Entity_Name (Name (Ostm)) then
4622 Ent : constant Entity_Id := Entity (Name (Ostm));
4625 -- If the procedure is marked No_Return, then likely it
4626 -- raises an exception, but in any case it is not coming
4627 -- back here, so turn on the flag.
4630 and then Ekind (Ent) = E_Procedure
4631 and then No_Return (Ent)
4633 Set_Trivial_Subprogram (Stm);
4641 -- Check for variables that are never modified
4648 -- If there is a separate spec, then transfer Never_Set_In_Source
4649 -- flags from out parameters to the corresponding entities in the
4650 -- body. The reason we do that is we want to post error flags on
4651 -- the body entities, not the spec entities.
4653 if Present (Spec_Id) then
4654 E1 := First_Entity (Spec_Id);
4655 while Present (E1) loop
4656 if Ekind (E1) = E_Out_Parameter then
4657 E2 := First_Entity (Body_Id);
4658 while Present (E2) loop
4659 exit when Chars (E1) = Chars (E2);
4663 if Present (E2) then
4664 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4672 -- Check references of the subprogram spec when we are dealing with
4673 -- an expression function due to it having a generated body.
4674 -- Otherwise, we simply check the formals of the subprogram body.
4676 if Present (Spec_Id)
4677 and then Is_Expression_Function (Spec_Id)
4679 Check_References (Spec_Id);
4681 Check_References (Body_Id);
4685 -- Check for nested subprogram, and mark outer level subprogram if so
4691 if Present (Spec_Id) then
4698 Ent := Enclosing_Subprogram (Ent);
4699 exit when No (Ent) or else Is_Subprogram (Ent);
4702 if Present (Ent) then
4703 Set_Has_Nested_Subprogram (Ent);
4707 -- Restore the limited views in the spec, if any, to let the back end
4708 -- process it without running into circularities.
4710 if Exch_Views /= No_Elist then
4711 Restore_Limited_Views (Exch_Views);
4714 if Mask_Types /= No_Elist then
4715 Unmask_Unfrozen_Types (Mask_Types);
4718 if Present (Desig_View) then
4719 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4723 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4724 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4725 end Analyze_Subprogram_Body_Helper;
4727 ------------------------------------
4728 -- Analyze_Subprogram_Declaration --
4729 ------------------------------------
4731 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4732 Scop : constant Entity_Id := Current_Scope;
4733 Designator : Entity_Id;
4735 Is_Completion : Boolean;
4736 -- Indicates whether a null procedure declaration is a completion
4739 -- Null procedures are not allowed in SPARK
4741 if Nkind (Specification (N)) = N_Procedure_Specification
4742 and then Null_Present (Specification (N))
4744 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4746 -- Null procedures are allowed in protected types, following the
4747 -- recent AI12-0147.
4749 if Is_Protected_Type (Current_Scope)
4750 and then Ada_Version < Ada_2012
4752 Error_Msg_N ("protected operation cannot be a null procedure", N);
4755 Analyze_Null_Procedure (N, Is_Completion);
4757 -- The null procedure acts as a body, nothing further is needed
4759 if Is_Completion then
4764 Designator := Analyze_Subprogram_Specification (Specification (N));
4766 -- A reference may already have been generated for the unit name, in
4767 -- which case the following call is redundant. However it is needed for
4768 -- declarations that are the rewriting of an expression function.
4770 Generate_Definition (Designator);
4772 -- Set the SPARK mode from the current context (may be overwritten later
4773 -- with explicit pragma). This is not done for entry barrier functions
4774 -- because they are generated outside the protected type and should not
4775 -- carry the mode of the enclosing context.
4777 if Nkind (N) = N_Subprogram_Declaration
4778 and then Is_Entry_Barrier_Function (N)
4783 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4784 Set_SPARK_Pragma_Inherited (Designator);
4787 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4788 -- the body of this subprogram is instantiated or inlined later and out
4789 -- of context. The body uses this attribute to restore the value of the
4792 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4793 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4796 -- Preserve relevant elaboration-related attributes of the context which
4797 -- are no longer available or very expensive to recompute once analysis,
4798 -- resolution, and expansion are over.
4800 Mark_Elaboration_Attributes
4801 (N_Id => Designator,
4805 if Debug_Flag_C then
4806 Write_Str ("==> subprogram spec ");
4807 Write_Name (Chars (Designator));
4808 Write_Str (" from ");
4809 Write_Location (Sloc (N));
4814 Validate_RCI_Subprogram_Declaration (N);
4815 New_Overloaded_Entity (Designator);
4816 Check_Delayed_Subprogram (Designator);
4818 -- If the type of the first formal of the current subprogram is a non-
4819 -- generic tagged private type, mark the subprogram as being a private
4820 -- primitive. Ditto if this is a function with controlling result, and
4821 -- the return type is currently private. In both cases, the type of the
4822 -- controlling argument or result must be in the current scope for the
4823 -- operation to be primitive.
4825 if Has_Controlling_Result (Designator)
4826 and then Is_Private_Type (Etype (Designator))
4827 and then Scope (Etype (Designator)) = Current_Scope
4828 and then not Is_Generic_Actual_Type (Etype (Designator))
4830 Set_Is_Private_Primitive (Designator);
4832 elsif Present (First_Formal (Designator)) then
4834 Formal_Typ : constant Entity_Id :=
4835 Etype (First_Formal (Designator));
4837 Set_Is_Private_Primitive (Designator,
4838 Is_Tagged_Type (Formal_Typ)
4839 and then Scope (Formal_Typ) = Current_Scope
4840 and then Is_Private_Type (Formal_Typ)
4841 and then not Is_Generic_Actual_Type (Formal_Typ));
4845 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4848 if Ada_Version >= Ada_2005
4849 and then Comes_From_Source (N)
4850 and then Is_Dispatching_Operation (Designator)
4857 if Has_Controlling_Result (Designator) then
4858 Etyp := Etype (Designator);
4861 E := First_Entity (Designator);
4863 and then Is_Formal (E)
4864 and then not Is_Controlling_Formal (E)
4872 if Is_Access_Type (Etyp) then
4873 Etyp := Directly_Designated_Type (Etyp);
4876 if Is_Interface (Etyp)
4877 and then not Is_Abstract_Subprogram (Designator)
4878 and then not (Ekind (Designator) = E_Procedure
4879 and then Null_Present (Specification (N)))
4881 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4883 -- Specialize error message based on procedures vs. functions,
4884 -- since functions can't be null subprograms.
4886 if Ekind (Designator) = E_Procedure then
4888 ("interface procedure % must be abstract or null", N);
4891 ("interface function % must be abstract", N);
4897 -- What is the following code for, it used to be
4899 -- ??? Set_Suppress_Elaboration_Checks
4900 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4902 -- The following seems equivalent, but a bit dubious
4904 if Elaboration_Checks_Suppressed (Designator) then
4905 Set_Kill_Elaboration_Checks (Designator);
4908 -- For a compilation unit, set body required. This flag will only be
4909 -- reset if a valid Import or Interface pragma is processed later on.
4911 if Nkind (Parent (N)) = N_Compilation_Unit then
4912 Set_Body_Required (Parent (N), True);
4914 if Ada_Version >= Ada_2005
4915 and then Nkind (Specification (N)) = N_Procedure_Specification
4916 and then Null_Present (Specification (N))
4919 ("null procedure cannot be declared at library level", N);
4923 Generate_Reference_To_Formals (Designator);
4924 Check_Eliminated (Designator);
4926 if Debug_Flag_C then
4928 Write_Str ("<== subprogram spec ");
4929 Write_Name (Chars (Designator));
4930 Write_Str (" from ");
4931 Write_Location (Sloc (N));
4935 -- Indicate that this is a protected operation, because it may be used
4936 -- in subsequent declarations within the protected type.
4938 if Is_Protected_Type (Current_Scope) then
4939 Set_Convention (Designator, Convention_Protected);
4942 List_Inherited_Pre_Post_Aspects (Designator);
4944 -- Process the aspects before establishing the proper categorization in
4945 -- case the subprogram is a compilation unit and one of its aspects is
4946 -- converted into a categorization pragma.
4948 if Has_Aspects (N) then
4949 Analyze_Aspect_Specifications (N, Designator);
4952 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4953 Set_Categorization_From_Scope (Designator, Scop);
4955 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4956 -- proper categorization of the unit based on its pragmas.
4959 Push_Scope (Designator);
4960 Set_Categorization_From_Pragmas (N);
4961 Validate_Categorization_Dependency (N, Designator);
4964 end Analyze_Subprogram_Declaration;
4966 --------------------------------------
4967 -- Analyze_Subprogram_Specification --
4968 --------------------------------------
4970 -- Reminder: N here really is a subprogram specification (not a subprogram
4971 -- declaration). This procedure is called to analyze the specification in
4972 -- both subprogram bodies and subprogram declarations (specs).
4974 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4975 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4976 -- Determine whether entity E denotes the spec or body of an invariant
4979 ------------------------------------
4980 -- Is_Invariant_Procedure_Or_Body --
4981 ------------------------------------
4983 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4984 Decl : constant Node_Id := Unit_Declaration_Node (E);
4988 if Nkind (Decl) = N_Subprogram_Body then
4989 Spec := Corresponding_Spec (Decl);
4996 and then Ekind (Spec) = E_Procedure
4997 and then (Is_Partial_Invariant_Procedure (Spec)
4998 or else Is_Invariant_Procedure (Spec));
4999 end Is_Invariant_Procedure_Or_Body;
5003 Designator : constant Entity_Id := Defining_Entity (N);
5004 Formals : constant List_Id := Parameter_Specifications (N);
5006 -- Start of processing for Analyze_Subprogram_Specification
5009 -- User-defined operator is not allowed in SPARK, except as a renaming
5011 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
5012 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
5014 Check_SPARK_05_Restriction
5015 ("user-defined operator is not allowed", N);
5018 -- Proceed with analysis. Do not emit a cross-reference entry if the
5019 -- specification comes from an expression function, because it may be
5020 -- the completion of a previous declaration. If it is not, the cross-
5021 -- reference entry will be emitted for the new subprogram declaration.
5023 if Nkind (Parent (N)) /= N_Expression_Function then
5024 Generate_Definition (Designator);
5027 if Nkind (N) = N_Function_Specification then
5028 Set_Ekind (Designator, E_Function);
5029 Set_Mechanism (Designator, Default_Mechanism);
5031 Set_Ekind (Designator, E_Procedure);
5032 Set_Etype (Designator, Standard_Void_Type);
5035 -- Flag Is_Inlined_Always is True by default, and reversed to False for
5036 -- those subprograms which could be inlined in GNATprove mode (because
5037 -- Body_To_Inline is non-Empty) but should not be inlined.
5039 if GNATprove_Mode then
5040 Set_Is_Inlined_Always (Designator);
5043 -- Introduce new scope for analysis of the formals and the return type
5045 Set_Scope (Designator, Current_Scope);
5047 if Present (Formals) then
5048 Push_Scope (Designator);
5049 Process_Formals (Formals, N);
5051 -- Check dimensions in N for formals with default expression
5053 Analyze_Dimension_Formals (N, Formals);
5055 -- Ada 2005 (AI-345): If this is an overriding operation of an
5056 -- inherited interface operation, and the controlling type is
5057 -- a synchronized type, replace the type with its corresponding
5058 -- record, to match the proper signature of an overriding operation.
5059 -- Same processing for an access parameter whose designated type is
5060 -- derived from a synchronized interface.
5062 -- This modification is not done for invariant procedures because
5063 -- the corresponding record may not necessarely be visible when the
5064 -- concurrent type acts as the full view of a private type.
5067 -- type Prot is private with Type_Invariant => ...;
5068 -- procedure ConcInvariant (Obj : Prot);
5070 -- protected type Prot is ...;
5071 -- type Concurrent_Record_Prot is record ...;
5072 -- procedure ConcInvariant (Obj : Prot) is
5074 -- end ConcInvariant;
5077 -- In the example above, both the spec and body of the invariant
5078 -- procedure must utilize the private type as the controlling type.
5080 if Ada_Version >= Ada_2005
5081 and then not Is_Invariant_Procedure_Or_Body (Designator)
5085 Formal_Typ : Entity_Id;
5086 Rec_Typ : Entity_Id;
5087 Desig_Typ : Entity_Id;
5090 Formal := First_Formal (Designator);
5091 while Present (Formal) loop
5092 Formal_Typ := Etype (Formal);
5094 if Is_Concurrent_Type (Formal_Typ)
5095 and then Present (Corresponding_Record_Type (Formal_Typ))
5097 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5099 if Present (Interfaces (Rec_Typ)) then
5100 Set_Etype (Formal, Rec_Typ);
5103 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5104 Desig_Typ := Designated_Type (Formal_Typ);
5106 if Is_Concurrent_Type (Desig_Typ)
5107 and then Present (Corresponding_Record_Type (Desig_Typ))
5109 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5111 if Present (Interfaces (Rec_Typ)) then
5112 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5117 Next_Formal (Formal);
5124 -- The subprogram scope is pushed and popped around the processing of
5125 -- the return type for consistency with call above to Process_Formals
5126 -- (which itself can call Analyze_Return_Type), and to ensure that any
5127 -- itype created for the return type will be associated with the proper
5130 elsif Nkind (N) = N_Function_Specification then
5131 Push_Scope (Designator);
5132 Analyze_Return_Type (N);
5138 if Nkind (N) = N_Function_Specification then
5140 -- Deal with operator symbol case
5142 if Nkind (Designator) = N_Defining_Operator_Symbol then
5143 Valid_Operator_Definition (Designator);
5146 May_Need_Actuals (Designator);
5148 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5149 -- the subprogram is abstract also. This does not apply to renaming
5150 -- declarations, where abstractness is inherited, and to subprogram
5151 -- bodies generated for stream operations, which become renamings as
5154 -- In case of primitives associated with abstract interface types
5155 -- the check is applied later (see Analyze_Subprogram_Declaration).
5157 if not Nkind_In (Original_Node (Parent (N)),
5158 N_Abstract_Subprogram_Declaration,
5159 N_Formal_Abstract_Subprogram_Declaration,
5160 N_Subprogram_Renaming_Declaration)
5162 if Is_Abstract_Type (Etype (Designator))
5163 and then not Is_Interface (Etype (Designator))
5166 ("function that returns abstract type must be abstract", N);
5168 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5169 -- access result whose designated type is abstract.
5171 elsif Ada_Version >= Ada_2012
5172 and then Nkind (Result_Definition (N)) = N_Access_Definition
5174 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5175 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5178 ("function whose access result designates abstract type "
5179 & "must be abstract", N);
5185 end Analyze_Subprogram_Specification;
5187 -----------------------
5188 -- Check_Conformance --
5189 -----------------------
5191 procedure Check_Conformance
5192 (New_Id : Entity_Id;
5194 Ctype : Conformance_Type;
5196 Conforms : out Boolean;
5197 Err_Loc : Node_Id := Empty;
5198 Get_Inst : Boolean := False;
5199 Skip_Controlling_Formals : Boolean := False)
5201 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5202 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5203 -- If Errmsg is True, then processing continues to post an error message
5204 -- for conformance error on given node. Two messages are output. The
5205 -- first message points to the previous declaration with a general "no
5206 -- conformance" message. The second is the detailed reason, supplied as
5207 -- Msg. The parameter N provide information for a possible & insertion
5208 -- in the message, and also provides the location for posting the
5209 -- message in the absence of a specified Err_Loc location.
5211 function Conventions_Match
5213 Id2 : Entity_Id) return Boolean;
5214 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5217 -----------------------
5218 -- Conformance_Error --
5219 -----------------------
5221 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5228 if No (Err_Loc) then
5234 Error_Msg_Sloc := Sloc (Old_Id);
5237 when Type_Conformant =>
5238 Error_Msg_N -- CODEFIX
5239 ("not type conformant with declaration#!", Enode);
5241 when Mode_Conformant =>
5242 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5244 ("not mode conformant with operation inherited#!",
5248 ("not mode conformant with declaration#!", Enode);
5251 when Subtype_Conformant =>
5252 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5254 ("not subtype conformant with operation inherited#!",
5258 ("not subtype conformant with declaration#!", Enode);
5261 when Fully_Conformant =>
5262 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5263 Error_Msg_N -- CODEFIX
5264 ("not fully conformant with operation inherited#!",
5267 Error_Msg_N -- CODEFIX
5268 ("not fully conformant with declaration#!", Enode);
5272 Error_Msg_NE (Msg, Enode, N);
5274 end Conformance_Error;
5276 -----------------------
5277 -- Conventions_Match --
5278 -----------------------
5280 function Conventions_Match
5282 Id2 : Entity_Id) return Boolean
5285 -- Ignore the conventions of anonymous access-to-subprogram types
5286 -- and subprogram types because these are internally generated and
5287 -- the only way these may receive a convention is if they inherit
5288 -- the convention of a related subprogram.
5290 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5293 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5298 -- Otherwise compare the conventions directly
5301 return Convention (Id1) = Convention (Id2);
5303 end Conventions_Match;
5307 Old_Type : constant Entity_Id := Etype (Old_Id);
5308 New_Type : constant Entity_Id := Etype (New_Id);
5309 Old_Formal : Entity_Id;
5310 New_Formal : Entity_Id;
5311 Access_Types_Match : Boolean;
5312 Old_Formal_Base : Entity_Id;
5313 New_Formal_Base : Entity_Id;
5315 -- Start of processing for Check_Conformance
5320 -- We need a special case for operators, since they don't appear
5323 if Ctype = Type_Conformant then
5324 if Ekind (New_Id) = E_Operator
5325 and then Operator_Matches_Spec (New_Id, Old_Id)
5331 -- If both are functions/operators, check return types conform
5333 if Old_Type /= Standard_Void_Type
5335 New_Type /= Standard_Void_Type
5337 -- If we are checking interface conformance we omit controlling
5338 -- arguments and result, because we are only checking the conformance
5339 -- of the remaining parameters.
5341 if Has_Controlling_Result (Old_Id)
5342 and then Has_Controlling_Result (New_Id)
5343 and then Skip_Controlling_Formals
5347 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5348 if Ctype >= Subtype_Conformant
5349 and then not Predicates_Match (Old_Type, New_Type)
5352 ("\predicate of return type does not match!", New_Id);
5355 ("\return type does not match!", New_Id);
5361 -- Ada 2005 (AI-231): In case of anonymous access types check the
5362 -- null-exclusion and access-to-constant attributes match.
5364 if Ada_Version >= Ada_2005
5365 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5367 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5368 or else Is_Access_Constant (Etype (Old_Type)) /=
5369 Is_Access_Constant (Etype (New_Type)))
5371 Conformance_Error ("\return type does not match!", New_Id);
5375 -- If either is a function/operator and the other isn't, error
5377 elsif Old_Type /= Standard_Void_Type
5378 or else New_Type /= Standard_Void_Type
5380 Conformance_Error ("\functions can only match functions!", New_Id);
5384 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5385 -- If this is a renaming as body, refine error message to indicate that
5386 -- the conflict is with the original declaration. If the entity is not
5387 -- frozen, the conventions don't have to match, the one of the renamed
5388 -- entity is inherited.
5390 if Ctype >= Subtype_Conformant then
5391 if not Conventions_Match (Old_Id, New_Id) then
5392 if not Is_Frozen (New_Id) then
5395 elsif Present (Err_Loc)
5396 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5397 and then Present (Corresponding_Spec (Err_Loc))
5399 Error_Msg_Name_1 := Chars (New_Id);
5401 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5402 Conformance_Error ("\prior declaration for% has convention %!");
5405 Conformance_Error ("\calling conventions do not match!");
5410 elsif Is_Formal_Subprogram (Old_Id)
5411 or else Is_Formal_Subprogram (New_Id)
5412 or else (Is_Subprogram (New_Id)
5413 and then Present (Alias (New_Id))
5414 and then Is_Formal_Subprogram (Alias (New_Id)))
5417 ("\formal subprograms are not subtype conformant "
5418 & "(RM 6.3.1 (17/3))");
5422 -- Deal with parameters
5424 -- Note: we use the entity information, rather than going directly
5425 -- to the specification in the tree. This is not only simpler, but
5426 -- absolutely necessary for some cases of conformance tests between
5427 -- operators, where the declaration tree simply does not exist.
5429 Old_Formal := First_Formal (Old_Id);
5430 New_Formal := First_Formal (New_Id);
5431 while Present (Old_Formal) and then Present (New_Formal) loop
5432 if Is_Controlling_Formal (Old_Formal)
5433 and then Is_Controlling_Formal (New_Formal)
5434 and then Skip_Controlling_Formals
5436 -- The controlling formals will have different types when
5437 -- comparing an interface operation with its match, but both
5438 -- or neither must be access parameters.
5440 if Is_Access_Type (Etype (Old_Formal))
5442 Is_Access_Type (Etype (New_Formal))
5444 goto Skip_Controlling_Formal;
5447 ("\access parameter does not match!", New_Formal);
5451 -- Ada 2012: Mode conformance also requires that formal parameters
5452 -- be both aliased, or neither.
5454 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5455 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5457 ("\aliased parameter mismatch!", New_Formal);
5461 if Ctype = Fully_Conformant then
5463 -- Names must match. Error message is more accurate if we do
5464 -- this before checking that the types of the formals match.
5466 if Chars (Old_Formal) /= Chars (New_Formal) then
5467 Conformance_Error ("\name& does not match!", New_Formal);
5469 -- Set error posted flag on new formal as well to stop
5470 -- junk cascaded messages in some cases.
5472 Set_Error_Posted (New_Formal);
5476 -- Null exclusion must match
5478 if Null_Exclusion_Present (Parent (Old_Formal))
5480 Null_Exclusion_Present (Parent (New_Formal))
5482 -- Only give error if both come from source. This should be
5483 -- investigated some time, since it should not be needed ???
5485 if Comes_From_Source (Old_Formal)
5487 Comes_From_Source (New_Formal)
5490 ("\null exclusion for& does not match", New_Formal);
5492 -- Mark error posted on the new formal to avoid duplicated
5493 -- complaint about types not matching.
5495 Set_Error_Posted (New_Formal);
5500 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5501 -- case occurs whenever a subprogram is being renamed and one of its
5502 -- parameters imposes a null exclusion. For example:
5504 -- type T is null record;
5505 -- type Acc_T is access T;
5506 -- subtype Acc_T_Sub is Acc_T;
5508 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5509 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5512 Old_Formal_Base := Etype (Old_Formal);
5513 New_Formal_Base := Etype (New_Formal);
5516 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5517 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5520 Access_Types_Match := Ada_Version >= Ada_2005
5522 -- Ensure that this rule is only applied when New_Id is a
5523 -- renaming of Old_Id.
5525 and then Nkind (Parent (Parent (New_Id))) =
5526 N_Subprogram_Renaming_Declaration
5527 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5528 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5529 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5531 -- Now handle the allowed access-type case
5533 and then Is_Access_Type (Old_Formal_Base)
5534 and then Is_Access_Type (New_Formal_Base)
5536 -- The type kinds must match. The only exception occurs with
5537 -- multiple generics of the form:
5540 -- type F is private; type A is private;
5541 -- type F_Ptr is access F; type A_Ptr is access A;
5542 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5543 -- package F_Pack is ... package A_Pack is
5544 -- package F_Inst is
5545 -- new F_Pack (A, A_Ptr, A_P);
5547 -- When checking for conformance between the parameters of A_P
5548 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5549 -- because the compiler has transformed A_Ptr into a subtype of
5550 -- F_Ptr. We catch this case in the code below.
5552 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5554 (Is_Generic_Type (Old_Formal_Base)
5555 and then Is_Generic_Type (New_Formal_Base)
5556 and then Is_Internal (New_Formal_Base)
5557 and then Etype (Etype (New_Formal_Base)) =
5559 and then Directly_Designated_Type (Old_Formal_Base) =
5560 Directly_Designated_Type (New_Formal_Base)
5561 and then ((Is_Itype (Old_Formal_Base)
5562 and then Can_Never_Be_Null (Old_Formal_Base))
5564 (Is_Itype (New_Formal_Base)
5565 and then Can_Never_Be_Null (New_Formal_Base)));
5567 -- Types must always match. In the visible part of an instance,
5568 -- usual overloading rules for dispatching operations apply, and
5569 -- we check base types (not the actual subtypes).
5571 if In_Instance_Visible_Part
5572 and then Is_Dispatching_Operation (New_Id)
5574 if not Conforming_Types
5575 (T1 => Base_Type (Etype (Old_Formal)),
5576 T2 => Base_Type (Etype (New_Formal)),
5578 Get_Inst => Get_Inst)
5579 and then not Access_Types_Match
5581 Conformance_Error ("\type of & does not match!", New_Formal);
5585 elsif not Conforming_Types
5586 (T1 => Old_Formal_Base,
5587 T2 => New_Formal_Base,
5589 Get_Inst => Get_Inst)
5590 and then not Access_Types_Match
5592 -- Don't give error message if old type is Any_Type. This test
5593 -- avoids some cascaded errors, e.g. in case of a bad spec.
5595 if Errmsg and then Old_Formal_Base = Any_Type then
5598 if Ctype >= Subtype_Conformant
5600 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5603 ("\predicate of & does not match!", New_Formal);
5606 ("\type of & does not match!", New_Formal);
5608 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5610 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5618 -- For mode conformance, mode must match
5620 if Ctype >= Mode_Conformant then
5621 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5622 if not Ekind_In (New_Id, E_Function, E_Procedure)
5623 or else not Is_Primitive_Wrapper (New_Id)
5625 Conformance_Error ("\mode of & does not match!", New_Formal);
5629 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5631 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5633 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5636 ("\mode of & does not match!", New_Formal);
5643 -- Part of mode conformance for access types is having the same
5644 -- constant modifier.
5646 elsif Access_Types_Match
5647 and then Is_Access_Constant (Old_Formal_Base) /=
5648 Is_Access_Constant (New_Formal_Base)
5651 ("\constant modifier does not match!", New_Formal);
5656 if Ctype >= Subtype_Conformant then
5658 -- Ada 2005 (AI-231): In case of anonymous access types check
5659 -- the null-exclusion and access-to-constant attributes must
5660 -- match. For null exclusion, we test the types rather than the
5661 -- formals themselves, since the attribute is only set reliably
5662 -- on the formals in the Ada 95 case, and we exclude the case
5663 -- where Old_Formal is marked as controlling, to avoid errors
5664 -- when matching completing bodies with dispatching declarations
5665 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5667 if Ada_Version >= Ada_2005
5668 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5669 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5671 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5672 Can_Never_Be_Null (Etype (New_Formal))
5674 not Is_Controlling_Formal (Old_Formal))
5676 Is_Access_Constant (Etype (Old_Formal)) /=
5677 Is_Access_Constant (Etype (New_Formal)))
5679 -- Do not complain if error already posted on New_Formal. This
5680 -- avoids some redundant error messages.
5682 and then not Error_Posted (New_Formal)
5684 -- It is allowed to omit the null-exclusion in case of stream
5685 -- attribute subprograms. We recognize stream subprograms
5686 -- through their TSS-generated suffix.
5689 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5692 if TSS_Name /= TSS_Stream_Read
5693 and then TSS_Name /= TSS_Stream_Write
5694 and then TSS_Name /= TSS_Stream_Input
5695 and then TSS_Name /= TSS_Stream_Output
5697 -- Here we have a definite conformance error. It is worth
5698 -- special casing the error message for the case of a
5699 -- controlling formal (which excludes null).
5701 if Is_Controlling_Formal (New_Formal) then
5702 Error_Msg_Node_2 := Scope (New_Formal);
5704 ("\controlling formal & of & excludes null, "
5705 & "declaration must exclude null as well",
5708 -- Normal case (couldn't we give more detail here???)
5712 ("\type of & does not match!", New_Formal);
5721 -- Full conformance checks
5723 if Ctype = Fully_Conformant then
5725 -- We have checked already that names match
5727 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5729 -- Check default expressions for in parameters
5732 NewD : constant Boolean :=
5733 Present (Default_Value (New_Formal));
5734 OldD : constant Boolean :=
5735 Present (Default_Value (Old_Formal));
5737 if NewD or OldD then
5739 -- The old default value has been analyzed because the
5740 -- current full declaration will have frozen everything
5741 -- before. The new default value has not been analyzed,
5742 -- so analyze it now before we check for conformance.
5745 Push_Scope (New_Id);
5746 Preanalyze_Spec_Expression
5747 (Default_Value (New_Formal), Etype (New_Formal));
5751 if not (NewD and OldD)
5752 or else not Fully_Conformant_Expressions
5753 (Default_Value (Old_Formal),
5754 Default_Value (New_Formal))
5757 ("\default expression for & does not match!",
5766 -- A couple of special checks for Ada 83 mode. These checks are
5767 -- skipped if either entity is an operator in package Standard,
5768 -- or if either old or new instance is not from the source program.
5770 if Ada_Version = Ada_83
5771 and then Sloc (Old_Id) > Standard_Location
5772 and then Sloc (New_Id) > Standard_Location
5773 and then Comes_From_Source (Old_Id)
5774 and then Comes_From_Source (New_Id)
5777 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5778 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5781 -- Explicit IN must be present or absent in both cases. This
5782 -- test is required only in the full conformance case.
5784 if In_Present (Old_Param) /= In_Present (New_Param)
5785 and then Ctype = Fully_Conformant
5788 ("\(Ada 83) IN must appear in both declarations",
5793 -- Grouping (use of comma in param lists) must be the same
5794 -- This is where we catch a misconformance like:
5797 -- A : Integer; B : Integer
5799 -- which are represented identically in the tree except
5800 -- for the setting of the flags More_Ids and Prev_Ids.
5802 if More_Ids (Old_Param) /= More_Ids (New_Param)
5803 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5806 ("\grouping of & does not match!", New_Formal);
5812 -- This label is required when skipping controlling formals
5814 <<Skip_Controlling_Formal>>
5816 Next_Formal (Old_Formal);
5817 Next_Formal (New_Formal);
5820 if Present (Old_Formal) then
5821 Conformance_Error ("\too few parameters!");
5824 elsif Present (New_Formal) then
5825 Conformance_Error ("\too many parameters!", New_Formal);
5828 end Check_Conformance;
5830 -----------------------
5831 -- Check_Conventions --
5832 -----------------------
5834 procedure Check_Conventions (Typ : Entity_Id) is
5835 Ifaces_List : Elist_Id;
5837 procedure Check_Convention (Op : Entity_Id);
5838 -- Verify that the convention of inherited dispatching operation Op is
5839 -- consistent among all subprograms it overrides. In order to minimize
5840 -- the search, Search_From is utilized to designate a specific point in
5841 -- the list rather than iterating over the whole list once more.
5843 ----------------------
5844 -- Check_Convention --
5845 ----------------------
5847 procedure Check_Convention (Op : Entity_Id) is
5848 Op_Conv : constant Convention_Id := Convention (Op);
5849 Iface_Conv : Convention_Id;
5850 Iface_Elmt : Elmt_Id;
5851 Iface_Prim_Elmt : Elmt_Id;
5852 Iface_Prim : Entity_Id;
5855 Iface_Elmt := First_Elmt (Ifaces_List);
5856 while Present (Iface_Elmt) loop
5858 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5859 while Present (Iface_Prim_Elmt) loop
5860 Iface_Prim := Node (Iface_Prim_Elmt);
5861 Iface_Conv := Convention (Iface_Prim);
5863 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5864 and then Iface_Conv /= Op_Conv
5867 ("inconsistent conventions in primitive operations", Typ);
5869 Error_Msg_Name_1 := Chars (Op);
5870 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5871 Error_Msg_Sloc := Sloc (Op);
5873 if Comes_From_Source (Op) or else No (Alias (Op)) then
5874 if not Present (Overridden_Operation (Op)) then
5875 Error_Msg_N ("\\primitive % defined #", Typ);
5878 ("\\overriding operation % with "
5879 & "convention % defined #", Typ);
5882 else pragma Assert (Present (Alias (Op)));
5883 Error_Msg_Sloc := Sloc (Alias (Op));
5884 Error_Msg_N ("\\inherited operation % with "
5885 & "convention % defined #", Typ);
5888 Error_Msg_Name_1 := Chars (Op);
5889 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5890 Error_Msg_Sloc := Sloc (Iface_Prim);
5891 Error_Msg_N ("\\overridden operation % with "
5892 & "convention % defined #", Typ);
5894 -- Avoid cascading errors
5899 Next_Elmt (Iface_Prim_Elmt);
5902 Next_Elmt (Iface_Elmt);
5904 end Check_Convention;
5908 Prim_Op : Entity_Id;
5909 Prim_Op_Elmt : Elmt_Id;
5911 -- Start of processing for Check_Conventions
5914 if not Has_Interfaces (Typ) then
5918 Collect_Interfaces (Typ, Ifaces_List);
5920 -- The algorithm checks every overriding dispatching operation against
5921 -- all the corresponding overridden dispatching operations, detecting
5922 -- differences in conventions.
5924 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5925 while Present (Prim_Op_Elmt) loop
5926 Prim_Op := Node (Prim_Op_Elmt);
5928 -- A small optimization: skip the predefined dispatching operations
5929 -- since they always have the same convention.
5931 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5932 Check_Convention (Prim_Op);
5935 Next_Elmt (Prim_Op_Elmt);
5937 end Check_Conventions;
5939 ------------------------------
5940 -- Check_Delayed_Subprogram --
5941 ------------------------------
5943 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5944 procedure Possible_Freeze (T : Entity_Id);
5945 -- T is the type of either a formal parameter or of the return type. If
5946 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5947 -- itself must be delayed.
5949 ---------------------
5950 -- Possible_Freeze --
5951 ---------------------
5953 procedure Possible_Freeze (T : Entity_Id) is
5954 Scop : constant Entity_Id := Scope (Designator);
5957 -- If the subprogram appears within a package instance (which may be
5958 -- the wrapper package of a subprogram instance) the freeze node for
5959 -- that package will freeze the subprogram at the proper place, so
5960 -- do not emit a freeze node for the subprogram, given that it may
5961 -- appear in the wrong scope.
5963 if Ekind (Scop) = E_Package
5964 and then not Comes_From_Source (Scop)
5965 and then Is_Generic_Instance (Scop)
5969 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5970 Set_Has_Delayed_Freeze (Designator);
5972 elsif Is_Access_Type (T)
5973 and then Has_Delayed_Freeze (Designated_Type (T))
5974 and then not Is_Frozen (Designated_Type (T))
5976 Set_Has_Delayed_Freeze (Designator);
5978 end Possible_Freeze;
5984 -- Start of processing for Check_Delayed_Subprogram
5987 -- All subprograms, including abstract subprograms, may need a freeze
5988 -- node if some formal type or the return type needs one.
5990 Possible_Freeze (Etype (Designator));
5991 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5993 -- Need delayed freeze if any of the formal types themselves need a
5994 -- delayed freeze and are not yet frozen.
5996 F := First_Formal (Designator);
5997 while Present (F) loop
5998 Possible_Freeze (Etype (F));
5999 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
6003 -- Mark functions that return by reference. Note that it cannot be done
6004 -- for delayed_freeze subprograms because the underlying returned type
6005 -- may not be known yet (for private types).
6007 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
6009 Typ : constant Entity_Id := Etype (Designator);
6010 Utyp : constant Entity_Id := Underlying_Type (Typ);
6013 if Is_Limited_View (Typ) then
6014 Set_Returns_By_Ref (Designator);
6016 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
6017 Set_Returns_By_Ref (Designator);
6021 end Check_Delayed_Subprogram;
6023 ------------------------------------
6024 -- Check_Discriminant_Conformance --
6025 ------------------------------------
6027 procedure Check_Discriminant_Conformance
6032 Old_Discr : Entity_Id := First_Discriminant (Prev);
6033 New_Discr : Node_Id := First (Discriminant_Specifications (N));
6034 New_Discr_Id : Entity_Id;
6035 New_Discr_Type : Entity_Id;
6037 procedure Conformance_Error (Msg : String; N : Node_Id);
6038 -- Post error message for conformance error on given node. Two messages
6039 -- are output. The first points to the previous declaration with a
6040 -- general "no conformance" message. The second is the detailed reason,
6041 -- supplied as Msg. The parameter N provide information for a possible
6042 -- & insertion in the message.
6044 -----------------------
6045 -- Conformance_Error --
6046 -----------------------
6048 procedure Conformance_Error (Msg : String; N : Node_Id) is
6050 Error_Msg_Sloc := Sloc (Prev_Loc);
6051 Error_Msg_N -- CODEFIX
6052 ("not fully conformant with declaration#!", N);
6053 Error_Msg_NE (Msg, N, N);
6054 end Conformance_Error;
6056 -- Start of processing for Check_Discriminant_Conformance
6059 while Present (Old_Discr) and then Present (New_Discr) loop
6060 New_Discr_Id := Defining_Identifier (New_Discr);
6062 -- The subtype mark of the discriminant on the full type has not
6063 -- been analyzed so we do it here. For an access discriminant a new
6066 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
6068 Access_Definition (N, Discriminant_Type (New_Discr));
6071 Analyze (Discriminant_Type (New_Discr));
6072 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6074 -- Ada 2005: if the discriminant definition carries a null
6075 -- exclusion, create an itype to check properly for consistency
6076 -- with partial declaration.
6078 if Is_Access_Type (New_Discr_Type)
6079 and then Null_Exclusion_Present (New_Discr)
6082 Create_Null_Excluding_Itype
6083 (T => New_Discr_Type,
6084 Related_Nod => New_Discr,
6085 Scope_Id => Current_Scope);
6089 if not Conforming_Types
6090 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6092 Conformance_Error ("type of & does not match!", New_Discr_Id);
6095 -- Treat the new discriminant as an occurrence of the old one,
6096 -- for navigation purposes, and fill in some semantic
6097 -- information, for completeness.
6099 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6100 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6101 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6106 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6107 Conformance_Error ("name & does not match!", New_Discr_Id);
6111 -- Default expressions must match
6114 NewD : constant Boolean :=
6115 Present (Expression (New_Discr));
6116 OldD : constant Boolean :=
6117 Present (Expression (Parent (Old_Discr)));
6120 if NewD or OldD then
6122 -- The old default value has been analyzed and expanded,
6123 -- because the current full declaration will have frozen
6124 -- everything before. The new default values have not been
6125 -- expanded, so expand now to check conformance.
6128 Preanalyze_Spec_Expression
6129 (Expression (New_Discr), New_Discr_Type);
6132 if not (NewD and OldD)
6133 or else not Fully_Conformant_Expressions
6134 (Expression (Parent (Old_Discr)),
6135 Expression (New_Discr))
6139 ("default expression for & does not match!",
6146 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6148 if Ada_Version = Ada_83 then
6150 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6153 -- Grouping (use of comma in param lists) must be the same
6154 -- This is where we catch a misconformance like:
6157 -- A : Integer; B : Integer
6159 -- which are represented identically in the tree except
6160 -- for the setting of the flags More_Ids and Prev_Ids.
6162 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6163 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6166 ("grouping of & does not match!", New_Discr_Id);
6172 Next_Discriminant (Old_Discr);
6176 if Present (Old_Discr) then
6177 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6180 elsif Present (New_Discr) then
6182 ("too many discriminants!", Defining_Identifier (New_Discr));
6185 end Check_Discriminant_Conformance;
6187 ----------------------------
6188 -- Check_Fully_Conformant --
6189 ----------------------------
6191 procedure Check_Fully_Conformant
6192 (New_Id : Entity_Id;
6194 Err_Loc : Node_Id := Empty)
6197 pragma Warnings (Off, Result);
6200 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6201 end Check_Fully_Conformant;
6203 --------------------------
6204 -- Check_Limited_Return --
6205 --------------------------
6207 procedure Check_Limited_Return
6213 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6214 -- replaced by anonymous access results. This is an incompatibility with
6215 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6216 -- controllable with special switch. ???
6218 -- A limited interface that is not immutably limited is OK
6220 if Is_Limited_Interface (R_Type)
6222 not (Is_Task_Interface (R_Type)
6223 or else Is_Protected_Interface (R_Type)
6224 or else Is_Synchronized_Interface (R_Type))
6228 elsif Is_Limited_Type (R_Type)
6229 and then not Is_Interface (R_Type)
6230 and then Comes_From_Source (N)
6231 and then not In_Instance_Body
6232 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6234 -- Error in Ada 2005
6236 if Ada_Version >= Ada_2005
6237 and then not Debug_Flag_Dot_L
6238 and then not GNAT_Mode
6241 ("(Ada 2005) cannot copy object of a limited type "
6242 & "(RM-2005 6.5(5.5/2))", Expr);
6244 if Is_Limited_View (R_Type) then
6246 ("\return by reference not permitted in Ada 2005", Expr);
6249 -- Warn in Ada 95 mode, to give folks a heads up about this
6252 -- In GNAT mode, this is just a warning, to allow it to be evilly
6253 -- turned off. Otherwise it is a real error.
6255 -- In a generic context, simplify the warning because it makes no
6256 -- sense to discuss pass-by-reference or copy.
6258 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6259 if Inside_A_Generic then
6261 ("return of limited object not permitted in Ada 2005 "
6262 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6264 elsif Is_Limited_View (R_Type) then
6266 ("return by reference not permitted in Ada 2005 "
6267 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6270 ("cannot copy object of a limited type in Ada 2005 "
6271 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6274 -- Ada 95 mode, and compatibility warnings disabled
6277 pragma Assert (Ada_Version <= Ada_95);
6278 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6279 return; -- skip continuation messages below
6282 if not Inside_A_Generic then
6284 ("\consider switching to return of access type", Expr);
6285 Explain_Limited_Type (R_Type, Expr);
6288 end Check_Limited_Return;
6290 ---------------------------
6291 -- Check_Mode_Conformant --
6292 ---------------------------
6294 procedure Check_Mode_Conformant
6295 (New_Id : Entity_Id;
6297 Err_Loc : Node_Id := Empty;
6298 Get_Inst : Boolean := False)
6301 pragma Warnings (Off, Result);
6304 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6305 end Check_Mode_Conformant;
6307 --------------------------------
6308 -- Check_Overriding_Indicator --
6309 --------------------------------
6311 procedure Check_Overriding_Indicator
6313 Overridden_Subp : Entity_Id;
6314 Is_Primitive : Boolean)
6320 -- No overriding indicator for literals
6322 if Ekind (Subp) = E_Enumeration_Literal then
6325 elsif Ekind (Subp) = E_Entry then
6326 Decl := Parent (Subp);
6328 -- No point in analyzing a malformed operator
6330 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6331 and then Error_Posted (Subp)
6336 Decl := Unit_Declaration_Node (Subp);
6339 if Nkind_In (Decl, N_Subprogram_Body,
6340 N_Subprogram_Body_Stub,
6341 N_Subprogram_Declaration,
6342 N_Abstract_Subprogram_Declaration,
6343 N_Subprogram_Renaming_Declaration)
6345 Spec := Specification (Decl);
6347 elsif Nkind (Decl) = N_Entry_Declaration then
6354 -- The overriding operation is type conformant with the overridden one,
6355 -- but the names of the formals are not required to match. If the names
6356 -- appear permuted in the overriding operation, this is a possible
6357 -- source of confusion that is worth diagnosing. Controlling formals
6358 -- often carry names that reflect the type, and it is not worthwhile
6359 -- requiring that their names match.
6361 if Present (Overridden_Subp)
6362 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6369 Form1 := First_Formal (Subp);
6370 Form2 := First_Formal (Overridden_Subp);
6372 -- If the overriding operation is a synchronized operation, skip
6373 -- the first parameter of the overridden operation, which is
6374 -- implicit in the new one. If the operation is declared in the
6375 -- body it is not primitive and all formals must match.
6377 if Is_Concurrent_Type (Scope (Subp))
6378 and then Is_Tagged_Type (Scope (Subp))
6379 and then not Has_Completion (Scope (Subp))
6381 Form2 := Next_Formal (Form2);
6384 if Present (Form1) then
6385 Form1 := Next_Formal (Form1);
6386 Form2 := Next_Formal (Form2);
6389 while Present (Form1) loop
6390 if not Is_Controlling_Formal (Form1)
6391 and then Present (Next_Formal (Form2))
6392 and then Chars (Form1) = Chars (Next_Formal (Form2))
6394 Error_Msg_Node_2 := Alias (Overridden_Subp);
6395 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6397 ("& does not match corresponding formal of&#",
6402 Next_Formal (Form1);
6403 Next_Formal (Form2);
6408 -- If there is an overridden subprogram, then check that there is no
6409 -- "not overriding" indicator, and mark the subprogram as overriding.
6410 -- This is not done if the overridden subprogram is marked as hidden,
6411 -- which can occur for the case of inherited controlled operations
6412 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6413 -- subprogram is not itself hidden. (Note: This condition could probably
6414 -- be simplified, leaving out the testing for the specific controlled
6415 -- cases, but it seems safer and clearer this way, and echoes similar
6416 -- special-case tests of this kind in other places.)
6418 if Present (Overridden_Subp)
6419 and then (not Is_Hidden (Overridden_Subp)
6421 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6424 and then Present (Alias (Overridden_Subp))
6425 and then not Is_Hidden (Alias (Overridden_Subp))))
6427 if Must_Not_Override (Spec) then
6428 Error_Msg_Sloc := Sloc (Overridden_Subp);
6430 if Ekind (Subp) = E_Entry then
6432 ("entry & overrides inherited operation #", Spec, Subp);
6435 ("subprogram & overrides inherited operation #", Spec, Subp);
6438 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6439 -- as an extension of Root_Controlled, and thus has a useless Adjust
6440 -- operation. This operation should not be inherited by other limited
6441 -- controlled types. An explicit Adjust for them is not overriding.
6443 elsif Must_Override (Spec)
6444 and then Chars (Overridden_Subp) = Name_Adjust
6445 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6446 and then Present (Alias (Overridden_Subp))
6447 and then In_Predefined_Unit (Alias (Overridden_Subp))
6450 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6451 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6453 elsif Is_Subprogram (Subp) then
6454 if Is_Init_Proc (Subp) then
6457 elsif No (Overridden_Operation (Subp)) then
6459 -- For entities generated by Derive_Subprograms the overridden
6460 -- operation is the inherited primitive (which is available
6461 -- through the attribute alias)
6463 if (Is_Dispatching_Operation (Subp)
6464 or else Is_Dispatching_Operation (Overridden_Subp))
6465 and then not Comes_From_Source (Overridden_Subp)
6466 and then Find_Dispatching_Type (Overridden_Subp) =
6467 Find_Dispatching_Type (Subp)
6468 and then Present (Alias (Overridden_Subp))
6469 and then Comes_From_Source (Alias (Overridden_Subp))
6471 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6472 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6475 Set_Overridden_Operation (Subp, Overridden_Subp);
6476 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6481 -- If primitive flag is set or this is a protected operation, then
6482 -- the operation is overriding at the point of its declaration, so
6483 -- warn if necessary. Otherwise it may have been declared before the
6484 -- operation it overrides and no check is required.
6487 and then not Must_Override (Spec)
6488 and then (Is_Primitive
6489 or else Ekind (Scope (Subp)) = E_Protected_Type)
6491 Style.Missing_Overriding (Decl, Subp);
6494 -- If Subp is an operator, it may override a predefined operation, if
6495 -- it is defined in the same scope as the type to which it applies.
6496 -- In that case Overridden_Subp is empty because of our implicit
6497 -- representation for predefined operators. We have to check whether the
6498 -- signature of Subp matches that of a predefined operator. Note that
6499 -- first argument provides the name of the operator, and the second
6500 -- argument the signature that may match that of a standard operation.
6501 -- If the indicator is overriding, then the operator must match a
6502 -- predefined signature, because we know already that there is no
6503 -- explicit overridden operation.
6505 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6506 if Must_Not_Override (Spec) then
6508 -- If this is not a primitive or a protected subprogram, then
6509 -- "not overriding" is illegal.
6512 and then Ekind (Scope (Subp)) /= E_Protected_Type
6514 Error_Msg_N ("overriding indicator only allowed "
6515 & "if subprogram is primitive", Subp);
6517 elsif Can_Override_Operator (Subp) then
6519 ("subprogram& overrides predefined operator ", Spec, Subp);
6522 elsif Must_Override (Spec) then
6523 if No (Overridden_Operation (Subp))
6524 and then not Can_Override_Operator (Subp)
6526 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6529 elsif not Error_Posted (Subp)
6530 and then Style_Check
6531 and then Can_Override_Operator (Subp)
6532 and then not In_Predefined_Unit (Subp)
6534 -- If style checks are enabled, indicate that the indicator is
6535 -- missing. However, at the point of declaration, the type of
6536 -- which this is a primitive operation may be private, in which
6537 -- case the indicator would be premature.
6539 if Has_Private_Declaration (Etype (Subp))
6540 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6544 Style.Missing_Overriding (Decl, Subp);
6548 elsif Must_Override (Spec) then
6549 if Ekind (Subp) = E_Entry then
6550 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6552 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6555 -- If the operation is marked "not overriding" and it's not primitive
6556 -- then an error is issued, unless this is an operation of a task or
6557 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6558 -- has been specified have already been checked above.
6560 elsif Must_Not_Override (Spec)
6561 and then not Is_Primitive
6562 and then Ekind (Subp) /= E_Entry
6563 and then Ekind (Scope (Subp)) /= E_Protected_Type
6566 ("overriding indicator only allowed if subprogram is primitive",
6570 end Check_Overriding_Indicator;
6576 -- Note: this procedure needs to know far too much about how the expander
6577 -- messes with exceptions. The use of the flag Exception_Junk and the
6578 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6579 -- works, but is not very clean. It would be better if the expansion
6580 -- routines would leave Original_Node working nicely, and we could use
6581 -- Original_Node here to ignore all the peculiar expander messing ???
6583 procedure Check_Returns
6587 Proc : Entity_Id := Empty)
6591 procedure Check_Statement_Sequence (L : List_Id);
6592 -- Internal recursive procedure to check a list of statements for proper
6593 -- termination by a return statement (or a transfer of control or a
6594 -- compound statement that is itself internally properly terminated).
6596 ------------------------------
6597 -- Check_Statement_Sequence --
6598 ------------------------------
6600 procedure Check_Statement_Sequence (L : List_Id) is
6605 function Assert_False return Boolean;
6606 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6607 -- rewritten as a null statement when assertions are off. The assert
6608 -- is not active, but it is still enough to kill the warning.
6614 function Assert_False return Boolean is
6615 Orig : constant Node_Id := Original_Node (Last_Stm);
6618 if Nkind (Orig) = N_Pragma
6619 and then Pragma_Name (Orig) = Name_Assert
6620 and then not Error_Posted (Orig)
6623 Arg : constant Node_Id :=
6624 First (Pragma_Argument_Associations (Orig));
6625 Exp : constant Node_Id := Expression (Arg);
6627 return Nkind (Exp) = N_Identifier
6628 and then Chars (Exp) = Name_False;
6638 Raise_Exception_Call : Boolean;
6639 -- Set True if statement sequence terminated by Raise_Exception call
6640 -- or a Reraise_Occurrence call.
6642 -- Start of processing for Check_Statement_Sequence
6645 Raise_Exception_Call := False;
6647 -- Get last real statement
6649 Last_Stm := Last (L);
6651 -- Deal with digging out exception handler statement sequences that
6652 -- have been transformed by the local raise to goto optimization.
6653 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6654 -- optimization has occurred, we are looking at something like:
6657 -- original stmts in block
6661 -- goto L1; | omitted if No_Exception_Propagation
6666 -- goto L3; -- skip handler when exception not raised
6668 -- <<L1>> -- target label for local exception
6682 -- and what we have to do is to dig out the estmts1 and estmts2
6683 -- sequences (which were the original sequences of statements in
6684 -- the exception handlers) and check them.
6686 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6691 exit when Nkind (Stm) /= N_Block_Statement;
6692 exit when not Exception_Junk (Stm);
6695 exit when Nkind (Stm) /= N_Label;
6696 exit when not Exception_Junk (Stm);
6697 Check_Statement_Sequence
6698 (Statements (Handled_Statement_Sequence (Next (Stm))));
6703 exit when Nkind (Stm) /= N_Goto_Statement;
6704 exit when not Exception_Junk (Stm);
6708 -- Don't count pragmas
6710 while Nkind (Last_Stm) = N_Pragma
6712 -- Don't count call to SS_Release (can happen after Raise_Exception)
6715 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6717 Nkind (Name (Last_Stm)) = N_Identifier
6719 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6721 -- Don't count exception junk
6724 (Nkind_In (Last_Stm, N_Goto_Statement,
6726 N_Object_Declaration)
6727 and then Exception_Junk (Last_Stm))
6728 or else Nkind (Last_Stm) in N_Push_xxx_Label
6729 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6731 -- Inserted code, such as finalization calls, is irrelevant: we only
6732 -- need to check original source.
6734 or else Is_Rewrite_Insertion (Last_Stm)
6739 -- Here we have the "real" last statement
6741 Kind := Nkind (Last_Stm);
6743 -- Transfer of control, OK. Note that in the No_Return procedure
6744 -- case, we already diagnosed any explicit return statements, so
6745 -- we can treat them as OK in this context.
6747 if Is_Transfer (Last_Stm) then
6750 -- Check cases of explicit non-indirect procedure calls
6752 elsif Kind = N_Procedure_Call_Statement
6753 and then Is_Entity_Name (Name (Last_Stm))
6755 -- Check call to Raise_Exception procedure which is treated
6756 -- specially, as is a call to Reraise_Occurrence.
6758 -- We suppress the warning in these cases since it is likely that
6759 -- the programmer really does not expect to deal with the case
6760 -- of Null_Occurrence, and thus would find a warning about a
6761 -- missing return curious, and raising Program_Error does not
6762 -- seem such a bad behavior if this does occur.
6764 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6765 -- behavior will be to raise Constraint_Error (see AI-329).
6767 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6769 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6771 Raise_Exception_Call := True;
6773 -- For Raise_Exception call, test first argument, if it is
6774 -- an attribute reference for a 'Identity call, then we know
6775 -- that the call cannot possibly return.
6778 Arg : constant Node_Id :=
6779 Original_Node (First_Actual (Last_Stm));
6781 if Nkind (Arg) = N_Attribute_Reference
6782 and then Attribute_Name (Arg) = Name_Identity
6789 -- If statement, need to look inside if there is an else and check
6790 -- each constituent statement sequence for proper termination.
6792 elsif Kind = N_If_Statement
6793 and then Present (Else_Statements (Last_Stm))
6795 Check_Statement_Sequence (Then_Statements (Last_Stm));
6796 Check_Statement_Sequence (Else_Statements (Last_Stm));
6798 if Present (Elsif_Parts (Last_Stm)) then
6800 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6803 while Present (Elsif_Part) loop
6804 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6812 -- Case statement, check each case for proper termination
6814 elsif Kind = N_Case_Statement then
6818 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6819 while Present (Case_Alt) loop
6820 Check_Statement_Sequence (Statements (Case_Alt));
6821 Next_Non_Pragma (Case_Alt);
6827 -- Block statement, check its handled sequence of statements
6829 elsif Kind = N_Block_Statement then
6835 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6844 -- Loop statement. If there is an iteration scheme, we can definitely
6845 -- fall out of the loop. Similarly if there is an exit statement, we
6846 -- can fall out. In either case we need a following return.
6848 elsif Kind = N_Loop_Statement then
6849 if Present (Iteration_Scheme (Last_Stm))
6850 or else Has_Exit (Entity (Identifier (Last_Stm)))
6854 -- A loop with no exit statement or iteration scheme is either
6855 -- an infinite loop, or it has some other exit (raise/return).
6856 -- In either case, no warning is required.
6862 -- Timed entry call, check entry call and delay alternatives
6864 -- Note: in expanded code, the timed entry call has been converted
6865 -- to a set of expanded statements on which the check will work
6866 -- correctly in any case.
6868 elsif Kind = N_Timed_Entry_Call then
6870 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6871 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6874 -- If statement sequence of entry call alternative is missing,
6875 -- then we can definitely fall through, and we post the error
6876 -- message on the entry call alternative itself.
6878 if No (Statements (ECA)) then
6881 -- If statement sequence of delay alternative is missing, then
6882 -- we can definitely fall through, and we post the error
6883 -- message on the delay alternative itself.
6885 -- Note: if both ECA and DCA are missing the return, then we
6886 -- post only one message, should be enough to fix the bugs.
6887 -- If not we will get a message next time on the DCA when the
6890 elsif No (Statements (DCA)) then
6893 -- Else check both statement sequences
6896 Check_Statement_Sequence (Statements (ECA));
6897 Check_Statement_Sequence (Statements (DCA));
6902 -- Conditional entry call, check entry call and else part
6904 -- Note: in expanded code, the conditional entry call has been
6905 -- converted to a set of expanded statements on which the check
6906 -- will work correctly in any case.
6908 elsif Kind = N_Conditional_Entry_Call then
6910 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6913 -- If statement sequence of entry call alternative is missing,
6914 -- then we can definitely fall through, and we post the error
6915 -- message on the entry call alternative itself.
6917 if No (Statements (ECA)) then
6920 -- Else check statement sequence and else part
6923 Check_Statement_Sequence (Statements (ECA));
6924 Check_Statement_Sequence (Else_Statements (Last_Stm));
6930 -- If we fall through, issue appropriate message
6934 -- Kill warning if last statement is a raise exception call,
6935 -- or a pragma Assert (False). Note that with assertions enabled,
6936 -- such a pragma has been converted into a raise exception call
6937 -- already, so the Assert_False is for the assertions off case.
6939 if not Raise_Exception_Call and then not Assert_False then
6941 -- In GNATprove mode, it is an error to have a missing return
6943 Error_Msg_Warn := SPARK_Mode /= On;
6945 -- Issue error message or warning
6948 ("RETURN statement missing following this statement<<!",
6951 ("\Program_Error ]<<!", Last_Stm);
6954 -- Note: we set Err even though we have not issued a warning
6955 -- because we still have a case of a missing return. This is
6956 -- an extremely marginal case, probably will never be noticed
6957 -- but we might as well get it right.
6961 -- Otherwise we have the case of a procedure marked No_Return
6964 if not Raise_Exception_Call then
6965 if GNATprove_Mode then
6967 ("implied return after this statement would have raised "
6968 & "Program_Error", Last_Stm);
6970 -- In normal compilation mode, do not warn on a generated call
6971 -- (e.g. in the body of a renaming as completion).
6973 elsif Comes_From_Source (Last_Stm) then
6975 ("implied return after this statement will raise "
6976 & "Program_Error??", Last_Stm);
6979 Error_Msg_Warn := SPARK_Mode /= On;
6981 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6985 RE : constant Node_Id :=
6986 Make_Raise_Program_Error (Sloc (Last_Stm),
6987 Reason => PE_Implicit_Return);
6989 Insert_After (Last_Stm, RE);
6993 end Check_Statement_Sequence;
6995 -- Start of processing for Check_Returns
6999 Check_Statement_Sequence (Statements (HSS));
7001 if Present (Exception_Handlers (HSS)) then
7002 Handler := First_Non_Pragma (Exception_Handlers (HSS));
7003 while Present (Handler) loop
7004 Check_Statement_Sequence (Statements (Handler));
7005 Next_Non_Pragma (Handler);
7010 ----------------------------
7011 -- Check_Subprogram_Order --
7012 ----------------------------
7014 procedure Check_Subprogram_Order (N : Node_Id) is
7016 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
7017 -- This is used to check if S1 > S2 in the sense required by this test,
7018 -- for example nameab < namec, but name2 < name10.
7020 -----------------------------
7021 -- Subprogram_Name_Greater --
7022 -----------------------------
7024 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
7029 -- Deal with special case where names are identical except for a
7030 -- numerical suffix. These are handled specially, taking the numeric
7031 -- ordering from the suffix into account.
7034 while S1 (L1) in '0' .. '9' loop
7039 while S2 (L2) in '0' .. '9' loop
7043 -- If non-numeric parts non-equal, do straight compare
7045 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
7048 -- If non-numeric parts equal, compare suffixed numeric parts. Note
7049 -- that a missing suffix is treated as numeric zero in this test.
7053 while L1 < S1'Last loop
7055 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
7059 while L2 < S2'Last loop
7061 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
7066 end Subprogram_Name_Greater;
7068 -- Start of processing for Check_Subprogram_Order
7071 -- Check body in alpha order if this is option
7074 and then Style_Check_Order_Subprograms
7075 and then Nkind (N) = N_Subprogram_Body
7076 and then Comes_From_Source (N)
7077 and then In_Extended_Main_Source_Unit (N)
7081 renames Scope_Stack.Table
7082 (Scope_Stack.Last).Last_Subprogram_Name;
7084 Body_Id : constant Entity_Id :=
7085 Defining_Entity (Specification (N));
7088 Get_Decoded_Name_String (Chars (Body_Id));
7091 if Subprogram_Name_Greater
7092 (LSN.all, Name_Buffer (1 .. Name_Len))
7094 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7100 LSN := new String'(Name_Buffer (1 .. Name_Len));
7103 end Check_Subprogram_Order;
7105 ------------------------------
7106 -- Check_Subtype_Conformant --
7107 ------------------------------
7109 procedure Check_Subtype_Conformant
7110 (New_Id : Entity_Id;
7112 Err_Loc : Node_Id := Empty;
7113 Skip_Controlling_Formals : Boolean := False;
7114 Get_Inst : Boolean := False)
7117 pragma Warnings (Off, Result);
7120 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7121 Skip_Controlling_Formals => Skip_Controlling_Formals,
7122 Get_Inst => Get_Inst);
7123 end Check_Subtype_Conformant;
7125 -----------------------------------
7126 -- Check_Synchronized_Overriding --
7127 -----------------------------------
7129 procedure Check_Synchronized_Overriding
7130 (Def_Id : Entity_Id;
7131 Overridden_Subp : out Entity_Id)
7133 Ifaces_List : Elist_Id;
7137 function Matches_Prefixed_View_Profile
7138 (Prim_Params : List_Id;
7139 Iface_Params : List_Id) return Boolean;
7140 -- Determine whether a subprogram's parameter profile Prim_Params
7141 -- matches that of a potentially overridden interface subprogram
7142 -- Iface_Params. Also determine if the type of first parameter of
7143 -- Iface_Params is an implemented interface.
7145 -----------------------------------
7146 -- Matches_Prefixed_View_Profile --
7147 -----------------------------------
7149 function Matches_Prefixed_View_Profile
7150 (Prim_Params : List_Id;
7151 Iface_Params : List_Id) return Boolean
7153 function Is_Implemented
7154 (Ifaces_List : Elist_Id;
7155 Iface : Entity_Id) return Boolean;
7156 -- Determine if Iface is implemented by the current task or
7159 --------------------
7160 -- Is_Implemented --
7161 --------------------
7163 function Is_Implemented
7164 (Ifaces_List : Elist_Id;
7165 Iface : Entity_Id) return Boolean
7167 Iface_Elmt : Elmt_Id;
7170 Iface_Elmt := First_Elmt (Ifaces_List);
7171 while Present (Iface_Elmt) loop
7172 if Node (Iface_Elmt) = Iface then
7176 Next_Elmt (Iface_Elmt);
7184 Iface_Id : Entity_Id;
7185 Iface_Param : Node_Id;
7186 Iface_Typ : Entity_Id;
7187 Prim_Id : Entity_Id;
7188 Prim_Param : Node_Id;
7189 Prim_Typ : Entity_Id;
7191 -- Start of processing for Matches_Prefixed_View_Profile
7194 Iface_Param := First (Iface_Params);
7195 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7197 if Is_Access_Type (Iface_Typ) then
7198 Iface_Typ := Designated_Type (Iface_Typ);
7201 Prim_Param := First (Prim_Params);
7203 -- The first parameter of the potentially overridden subprogram must
7204 -- be an interface implemented by Prim.
7206 if not Is_Interface (Iface_Typ)
7207 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7212 -- The checks on the object parameters are done, so move on to the
7213 -- rest of the parameters.
7215 if not In_Scope then
7216 Prim_Param := Next (Prim_Param);
7219 Iface_Param := Next (Iface_Param);
7220 while Present (Iface_Param) and then Present (Prim_Param) loop
7221 Iface_Id := Defining_Identifier (Iface_Param);
7222 Iface_Typ := Find_Parameter_Type (Iface_Param);
7224 Prim_Id := Defining_Identifier (Prim_Param);
7225 Prim_Typ := Find_Parameter_Type (Prim_Param);
7227 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7228 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7229 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7231 Iface_Typ := Designated_Type (Iface_Typ);
7232 Prim_Typ := Designated_Type (Prim_Typ);
7235 -- Case of multiple interface types inside a parameter profile
7237 -- (Obj_Param : in out Iface; ...; Param : Iface)
7239 -- If the interface type is implemented, then the matching type in
7240 -- the primitive should be the implementing record type.
7242 if Ekind (Iface_Typ) = E_Record_Type
7243 and then Is_Interface (Iface_Typ)
7244 and then Is_Implemented (Ifaces_List, Iface_Typ)
7246 if Prim_Typ /= Typ then
7250 -- The two parameters must be both mode and subtype conformant
7252 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7254 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7263 -- One of the two lists contains more parameters than the other
7265 if Present (Iface_Param) or else Present (Prim_Param) then
7270 end Matches_Prefixed_View_Profile;
7272 -- Start of processing for Check_Synchronized_Overriding
7275 Overridden_Subp := Empty;
7277 -- Def_Id must be an entry or a subprogram. We should skip predefined
7278 -- primitives internally generated by the front end; however at this
7279 -- stage predefined primitives are still not fully decorated. As a
7280 -- minor optimization we skip here internally generated subprograms.
7282 if (Ekind (Def_Id) /= E_Entry
7283 and then Ekind (Def_Id) /= E_Function
7284 and then Ekind (Def_Id) /= E_Procedure)
7285 or else not Comes_From_Source (Def_Id)
7290 -- Search for the concurrent declaration since it contains the list of
7291 -- all implemented interfaces. In this case, the subprogram is declared
7292 -- within the scope of a protected or a task type.
7294 if Present (Scope (Def_Id))
7295 and then Is_Concurrent_Type (Scope (Def_Id))
7296 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7298 Typ := Scope (Def_Id);
7301 -- The enclosing scope is not a synchronized type and the subprogram
7304 elsif No (First_Formal (Def_Id)) then
7307 -- The subprogram has formals and hence it may be a primitive of a
7311 Typ := Etype (First_Formal (Def_Id));
7313 if Is_Access_Type (Typ) then
7314 Typ := Directly_Designated_Type (Typ);
7317 if Is_Concurrent_Type (Typ)
7318 and then not Is_Generic_Actual_Type (Typ)
7322 -- This case occurs when the concurrent type is declared within a
7323 -- generic unit. As a result the corresponding record has been built
7324 -- and used as the type of the first formal, we just have to retrieve
7325 -- the corresponding concurrent type.
7327 elsif Is_Concurrent_Record_Type (Typ)
7328 and then not Is_Class_Wide_Type (Typ)
7329 and then Present (Corresponding_Concurrent_Type (Typ))
7331 Typ := Corresponding_Concurrent_Type (Typ);
7339 -- There is no overriding to check if this is an inherited operation in
7340 -- a type derivation for a generic actual.
7342 Collect_Interfaces (Typ, Ifaces_List);
7344 if Is_Empty_Elmt_List (Ifaces_List) then
7348 -- Determine whether entry or subprogram Def_Id overrides a primitive
7349 -- operation that belongs to one of the interfaces in Ifaces_List.
7352 Candidate : Entity_Id := Empty;
7353 Hom : Entity_Id := Empty;
7354 Subp : Entity_Id := Empty;
7357 -- Traverse the homonym chain, looking for a potentially overridden
7358 -- subprogram that belongs to an implemented interface.
7360 Hom := Current_Entity_In_Scope (Def_Id);
7361 while Present (Hom) loop
7365 or else not Is_Overloadable (Subp)
7366 or else not Is_Primitive (Subp)
7367 or else not Is_Dispatching_Operation (Subp)
7368 or else not Present (Find_Dispatching_Type (Subp))
7369 or else not Is_Interface (Find_Dispatching_Type (Subp))
7373 -- Entries and procedures can override abstract or null interface
7376 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7377 and then Ekind (Subp) = E_Procedure
7378 and then Matches_Prefixed_View_Profile
7379 (Parameter_Specifications (Parent (Def_Id)),
7380 Parameter_Specifications (Parent (Subp)))
7384 -- For an overridden subprogram Subp, check whether the mode
7385 -- of its first parameter is correct depending on the kind of
7386 -- synchronized type.
7389 Formal : constant Node_Id := First_Formal (Candidate);
7392 -- In order for an entry or a protected procedure to
7393 -- override, the first parameter of the overridden routine
7394 -- must be of mode "out", "in out", or access-to-variable.
7396 if Ekind_In (Candidate, E_Entry, E_Procedure)
7397 and then Is_Protected_Type (Typ)
7398 and then Ekind (Formal) /= E_In_Out_Parameter
7399 and then Ekind (Formal) /= E_Out_Parameter
7400 and then Nkind (Parameter_Type (Parent (Formal))) /=
7405 -- All other cases are OK since a task entry or routine does
7406 -- not have a restriction on the mode of the first parameter
7407 -- of the overridden interface routine.
7410 Overridden_Subp := Candidate;
7415 -- Functions can override abstract interface functions
7417 elsif Ekind (Def_Id) = E_Function
7418 and then Ekind (Subp) = E_Function
7419 and then Matches_Prefixed_View_Profile
7420 (Parameter_Specifications (Parent (Def_Id)),
7421 Parameter_Specifications (Parent (Subp)))
7422 and then Etype (Def_Id) = Etype (Subp)
7426 -- If an inherited subprogram is implemented by a protected
7427 -- function, then the first parameter of the inherited
7428 -- subprogram shall be of mode in, but not an access-to-
7429 -- variable parameter (RM 9.4(11/9)).
7431 if Present (First_Formal (Subp))
7432 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7434 (not Is_Access_Type (Etype (First_Formal (Subp)))
7436 Is_Access_Constant (Etype (First_Formal (Subp))))
7438 Overridden_Subp := Subp;
7443 Hom := Homonym (Hom);
7446 -- After examining all candidates for overriding, we are left with
7447 -- the best match, which is a mode-incompatible interface routine.
7449 if In_Scope and then Present (Candidate) then
7450 Error_Msg_PT (Def_Id, Candidate);
7453 Overridden_Subp := Candidate;
7456 end Check_Synchronized_Overriding;
7458 ---------------------------
7459 -- Check_Type_Conformant --
7460 ---------------------------
7462 procedure Check_Type_Conformant
7463 (New_Id : Entity_Id;
7465 Err_Loc : Node_Id := Empty)
7468 pragma Warnings (Off, Result);
7471 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7472 end Check_Type_Conformant;
7474 ---------------------------
7475 -- Can_Override_Operator --
7476 ---------------------------
7478 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7482 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7486 Typ := Base_Type (Etype (First_Formal (Subp)));
7488 -- Check explicitly that the operation is a primitive of the type
7490 return Operator_Matches_Spec (Subp, Subp)
7491 and then not Is_Generic_Type (Typ)
7492 and then Scope (Subp) = Scope (Typ)
7493 and then not Is_Class_Wide_Type (Typ);
7495 end Can_Override_Operator;
7497 ----------------------
7498 -- Conforming_Types --
7499 ----------------------
7501 function Conforming_Types
7504 Ctype : Conformance_Type;
7505 Get_Inst : Boolean := False) return Boolean
7507 function Base_Types_Match
7509 Typ_2 : Entity_Id) return Boolean;
7510 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7511 -- in different scopes (e.g. parent and child instances), then verify
7512 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7513 -- the same subtype chain. The whole purpose of this procedure is to
7514 -- prevent spurious ambiguities in an instantiation that may arise if
7515 -- two distinct generic types are instantiated with the same actual.
7517 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7518 -- An access parameter can designate an incomplete type. If the
7519 -- incomplete type is the limited view of a type from a limited_
7520 -- with_clause, check whether the non-limited view is available.
7521 -- If it is a (non-limited) incomplete type, get the full view.
7523 function Matches_Limited_With_View
7525 Typ_2 : Entity_Id) return Boolean;
7526 -- Returns True if and only if either Typ_1 denotes a limited view of
7527 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7528 -- the limited with view of a type is used in a subprogram declaration
7529 -- and the subprogram body is in the scope of a regular with clause for
7530 -- the same unit. In such a case, the two type entities are considered
7531 -- identical for purposes of conformance checking.
7533 ----------------------
7534 -- Base_Types_Match --
7535 ----------------------
7537 function Base_Types_Match
7539 Typ_2 : Entity_Id) return Boolean
7541 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7542 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7545 if Typ_1 = Typ_2 then
7548 elsif Base_1 = Base_2 then
7550 -- The following is too permissive. A more precise test should
7551 -- check that the generic actual is an ancestor subtype of the
7554 -- See code in Find_Corresponding_Spec that applies an additional
7555 -- filter to handle accidental amiguities in instances.
7558 not Is_Generic_Actual_Type (Typ_1)
7559 or else not Is_Generic_Actual_Type (Typ_2)
7560 or else Scope (Typ_1) /= Scope (Typ_2);
7562 -- If Typ_2 is a generic actual type it is declared as the subtype of
7563 -- the actual. If that actual is itself a subtype we need to use its
7564 -- own base type to check for compatibility.
7566 elsif Ekind (Base_2) = Ekind (Typ_2)
7567 and then Base_1 = Base_Type (Base_2)
7571 elsif Ekind (Base_1) = Ekind (Typ_1)
7572 and then Base_2 = Base_Type (Base_1)
7579 end Base_Types_Match;
7581 --------------------------
7582 -- Find_Designated_Type --
7583 --------------------------
7585 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7589 Desig := Directly_Designated_Type (Typ);
7591 if Ekind (Desig) = E_Incomplete_Type then
7593 -- If regular incomplete type, get full view if available
7595 if Present (Full_View (Desig)) then
7596 Desig := Full_View (Desig);
7598 -- If limited view of a type, get non-limited view if available,
7599 -- and check again for a regular incomplete type.
7601 elsif Present (Non_Limited_View (Desig)) then
7602 Desig := Get_Full_View (Non_Limited_View (Desig));
7607 end Find_Designated_Type;
7609 -------------------------------
7610 -- Matches_Limited_With_View --
7611 -------------------------------
7613 function Matches_Limited_With_View
7615 Typ_2 : Entity_Id) return Boolean
7617 function Is_Matching_Limited_View
7619 View : Entity_Id) return Boolean;
7620 -- Determine whether non-limited view View denotes type Typ in some
7621 -- conformant fashion.
7623 ------------------------------
7624 -- Is_Matching_Limited_View --
7625 ------------------------------
7627 function Is_Matching_Limited_View
7629 View : Entity_Id) return Boolean
7631 Root_Typ : Entity_Id;
7632 Root_View : Entity_Id;
7635 -- The non-limited view directly denotes the type
7640 -- The type is a subtype of the non-limited view
7642 elsif Is_Subtype_Of (Typ, View) then
7645 -- Both the non-limited view and the type denote class-wide types
7647 elsif Is_Class_Wide_Type (Typ)
7648 and then Is_Class_Wide_Type (View)
7650 Root_Typ := Root_Type (Typ);
7651 Root_View := Root_Type (View);
7653 if Root_Typ = Root_View then
7656 -- An incomplete tagged type and its full view may receive two
7657 -- distinct class-wide types when the related package has not
7658 -- been analyzed yet.
7661 -- type T is tagged; -- CW_1
7662 -- type T is tagged null record; -- CW_2
7665 -- This is because the package lacks any semantic information
7666 -- that may eventually link both views of T. As a consequence,
7667 -- a client of the limited view of Pack will see CW_2 while a
7668 -- client of the non-limited view of Pack will see CW_1.
7670 elsif Is_Incomplete_Type (Root_Typ)
7671 and then Present (Full_View (Root_Typ))
7672 and then Full_View (Root_Typ) = Root_View
7676 elsif Is_Incomplete_Type (Root_View)
7677 and then Present (Full_View (Root_View))
7678 and then Full_View (Root_View) = Root_Typ
7685 end Is_Matching_Limited_View;
7687 -- Start of processing for Matches_Limited_With_View
7690 -- In some cases a type imported through a limited_with clause, and
7691 -- its non-limited view are both visible, for example in an anonymous
7692 -- access-to-class-wide type in a formal, or when building the body
7693 -- for a subprogram renaming after the subprogram has been frozen.
7694 -- In these cases both entities designate the same type. In addition,
7695 -- if one of them is an actual in an instance, it may be a subtype of
7696 -- the non-limited view of the other.
7698 if From_Limited_With (Typ_1)
7699 and then From_Limited_With (Typ_2)
7700 and then Available_View (Typ_1) = Available_View (Typ_2)
7704 elsif From_Limited_With (Typ_1) then
7705 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7707 elsif From_Limited_With (Typ_2) then
7708 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7713 end Matches_Limited_With_View;
7717 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7719 Type_1 : Entity_Id := T1;
7720 Type_2 : Entity_Id := T2;
7722 -- Start of processing for Conforming_Types
7725 -- The context is an instance association for a formal access-to-
7726 -- subprogram type; the formal parameter types require mapping because
7727 -- they may denote other formal parameters of the generic unit.
7730 Type_1 := Get_Instance_Of (T1);
7731 Type_2 := Get_Instance_Of (T2);
7734 -- If one of the types is a view of the other introduced by a limited
7735 -- with clause, treat these as conforming for all purposes.
7737 if Matches_Limited_With_View (T1, T2) then
7740 elsif Base_Types_Match (Type_1, Type_2) then
7741 if Ctype <= Mode_Conformant then
7746 Subtypes_Statically_Match (Type_1, Type_2)
7747 and then Dimensions_Match (Type_1, Type_2);
7750 elsif Is_Incomplete_Or_Private_Type (Type_1)
7751 and then Present (Full_View (Type_1))
7752 and then Base_Types_Match (Full_View (Type_1), Type_2)
7755 Ctype <= Mode_Conformant
7756 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7758 elsif Ekind (Type_2) = E_Incomplete_Type
7759 and then Present (Full_View (Type_2))
7760 and then Base_Types_Match (Type_1, Full_View (Type_2))
7763 Ctype <= Mode_Conformant
7764 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7766 elsif Is_Private_Type (Type_2)
7767 and then In_Instance
7768 and then Present (Full_View (Type_2))
7769 and then Base_Types_Match (Type_1, Full_View (Type_2))
7772 Ctype <= Mode_Conformant
7773 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7775 -- Another confusion between views in a nested instance with an
7776 -- actual private type whose full view is not in scope.
7778 elsif Ekind (Type_2) = E_Private_Subtype
7779 and then In_Instance
7780 and then Etype (Type_2) = Type_1
7784 -- In Ada 2012, incomplete types (including limited views) can appear
7785 -- as actuals in instantiations, where they are conformant to the
7786 -- corresponding incomplete formal.
7788 elsif Is_Incomplete_Type (Type_1)
7789 and then Is_Incomplete_Type (Type_2)
7790 and then In_Instance
7791 and then (Used_As_Generic_Actual (Type_1)
7792 or else Used_As_Generic_Actual (Type_2))
7797 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7798 -- treated recursively because they carry a signature. As far as
7799 -- conformance is concerned, convention plays no role, and either
7800 -- or both could be access to protected subprograms.
7802 Are_Anonymous_Access_To_Subprogram_Types :=
7803 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7804 E_Anonymous_Access_Protected_Subprogram_Type)
7806 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7807 E_Anonymous_Access_Protected_Subprogram_Type);
7809 -- Test anonymous access type case. For this case, static subtype
7810 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7811 -- the base types because we may have built internal subtype entities
7812 -- to handle null-excluding types (see Process_Formals).
7814 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7816 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7818 -- Ada 2005 (AI-254)
7820 or else Are_Anonymous_Access_To_Subprogram_Types
7823 Desig_1 : Entity_Id;
7824 Desig_2 : Entity_Id;
7827 -- In Ada 2005, access constant indicators must match for
7828 -- subtype conformance.
7830 if Ada_Version >= Ada_2005
7831 and then Ctype >= Subtype_Conformant
7833 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7838 Desig_1 := Find_Designated_Type (Type_1);
7839 Desig_2 := Find_Designated_Type (Type_2);
7841 -- If the context is an instance association for a formal
7842 -- access-to-subprogram type; formal access parameter designated
7843 -- types require mapping because they may denote other formal
7844 -- parameters of the generic unit.
7847 Desig_1 := Get_Instance_Of (Desig_1);
7848 Desig_2 := Get_Instance_Of (Desig_2);
7851 -- It is possible for a Class_Wide_Type to be introduced for an
7852 -- incomplete type, in which case there is a separate class_ wide
7853 -- type for the full view. The types conform if their Etypes
7854 -- conform, i.e. one may be the full view of the other. This can
7855 -- only happen in the context of an access parameter, other uses
7856 -- of an incomplete Class_Wide_Type are illegal.
7858 if Is_Class_Wide_Type (Desig_1)
7860 Is_Class_Wide_Type (Desig_2)
7864 (Etype (Base_Type (Desig_1)),
7865 Etype (Base_Type (Desig_2)), Ctype);
7867 elsif Are_Anonymous_Access_To_Subprogram_Types then
7868 if Ada_Version < Ada_2005 then
7870 Ctype = Type_Conformant
7871 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7873 -- We must check the conformance of the signatures themselves
7877 Conformant : Boolean;
7880 (Desig_1, Desig_2, Ctype, False, Conformant);
7885 -- A limited view of an actual matches the corresponding
7886 -- incomplete formal.
7888 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7889 and then From_Limited_With (Desig_2)
7890 and then Used_As_Generic_Actual (Etype (Desig_2))
7895 return Base_Type (Desig_1) = Base_Type (Desig_2)
7896 and then (Ctype = Type_Conformant
7898 Subtypes_Statically_Match (Desig_1, Desig_2));
7902 -- Otherwise definitely no match
7905 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7906 and then Is_Access_Type (Type_2))
7907 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7908 and then Is_Access_Type (Type_1)))
7911 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7913 May_Hide_Profile := True;
7918 end Conforming_Types;
7920 --------------------------
7921 -- Create_Extra_Formals --
7922 --------------------------
7924 procedure Create_Extra_Formals (E : Entity_Id) is
7925 First_Extra : Entity_Id := Empty;
7927 Last_Extra : Entity_Id := Empty;
7929 function Add_Extra_Formal
7930 (Assoc_Entity : Entity_Id;
7933 Suffix : String) return Entity_Id;
7934 -- Add an extra formal to the current list of formals and extra formals.
7935 -- The extra formal is added to the end of the list of extra formals,
7936 -- and also returned as the result. These formals are always of mode IN.
7937 -- The new formal has the type Typ, is declared in Scope, and its name
7938 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7939 -- The following suffixes are currently used. They should not be changed
7940 -- without coordinating with CodePeer, which makes use of these to
7941 -- provide better messages.
7943 -- O denotes the Constrained bit.
7944 -- L denotes the accessibility level.
7945 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7946 -- the full list in exp_ch6.BIP_Formal_Kind.
7948 ----------------------
7949 -- Add_Extra_Formal --
7950 ----------------------
7952 function Add_Extra_Formal
7953 (Assoc_Entity : Entity_Id;
7956 Suffix : String) return Entity_Id
7958 EF : constant Entity_Id :=
7959 Make_Defining_Identifier (Sloc (Assoc_Entity),
7960 Chars => New_External_Name (Chars (Assoc_Entity),
7964 -- A little optimization. Never generate an extra formal for the
7965 -- _init operand of an initialization procedure, since it could
7968 if Chars (Formal) = Name_uInit then
7972 Set_Ekind (EF, E_In_Parameter);
7973 Set_Actual_Subtype (EF, Typ);
7974 Set_Etype (EF, Typ);
7975 Set_Scope (EF, Scope);
7976 Set_Mechanism (EF, Default_Mechanism);
7977 Set_Formal_Validity (EF);
7979 if No (First_Extra) then
7981 Set_Extra_Formals (Scope, EF);
7984 if Present (Last_Extra) then
7985 Set_Extra_Formal (Last_Extra, EF);
7991 end Add_Extra_Formal;
7995 Formal_Type : Entity_Id;
7996 P_Formal : Entity_Id := Empty;
7998 -- Start of processing for Create_Extra_Formals
8001 -- We never generate extra formals if expansion is not active because we
8002 -- don't need them unless we are generating code.
8004 if not Expander_Active then
8008 -- No need to generate extra formals in interface thunks whose target
8009 -- primitive has no extra formals.
8011 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
8015 -- If this is a derived subprogram then the subtypes of the parent
8016 -- subprogram's formal parameters will be used to determine the need
8017 -- for extra formals.
8019 if Is_Overloadable (E) and then Present (Alias (E)) then
8020 P_Formal := First_Formal (Alias (E));
8023 Formal := First_Formal (E);
8024 while Present (Formal) loop
8025 Last_Extra := Formal;
8026 Next_Formal (Formal);
8029 -- If Extra_Formals were already created, don't do it again. This
8030 -- situation may arise for subprogram types created as part of
8031 -- dispatching calls (see Expand_Dispatching_Call).
8033 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
8037 -- If the subprogram is a predefined dispatching subprogram then don't
8038 -- generate any extra constrained or accessibility level formals. In
8039 -- general we suppress these for internal subprograms (by not calling
8040 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
8041 -- generated stream attributes do get passed through because extra
8042 -- build-in-place formals are needed in some cases (limited 'Input).
8044 if Is_Predefined_Internal_Operation (E) then
8045 goto Test_For_Func_Result_Extras;
8048 Formal := First_Formal (E);
8049 while Present (Formal) loop
8051 -- Create extra formal for supporting the attribute 'Constrained.
8052 -- The case of a private type view without discriminants also
8053 -- requires the extra formal if the underlying type has defaulted
8056 if Ekind (Formal) /= E_In_Parameter then
8057 if Present (P_Formal) then
8058 Formal_Type := Etype (P_Formal);
8060 Formal_Type := Etype (Formal);
8063 -- Do not produce extra formals for Unchecked_Union parameters.
8064 -- Jump directly to the end of the loop.
8066 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
8067 goto Skip_Extra_Formal_Generation;
8070 if not Has_Discriminants (Formal_Type)
8071 and then Ekind (Formal_Type) in Private_Kind
8072 and then Present (Underlying_Type (Formal_Type))
8074 Formal_Type := Underlying_Type (Formal_Type);
8077 -- Suppress the extra formal if formal's subtype is constrained or
8078 -- indefinite, or we're compiling for Ada 2012 and the underlying
8079 -- type is tagged and limited. In Ada 2012, a limited tagged type
8080 -- can have defaulted discriminants, but 'Constrained is required
8081 -- to return True, so the formal is never needed (see AI05-0214).
8082 -- Note that this ensures consistency of calling sequences for
8083 -- dispatching operations when some types in a class have defaults
8084 -- on discriminants and others do not (and requiring the extra
8085 -- formal would introduce distributed overhead).
8087 -- If the type does not have a completion yet, treat as prior to
8088 -- Ada 2012 for consistency.
8090 if Has_Discriminants (Formal_Type)
8091 and then not Is_Constrained (Formal_Type)
8092 and then Is_Definite_Subtype (Formal_Type)
8093 and then (Ada_Version < Ada_2012
8094 or else No (Underlying_Type (Formal_Type))
8096 (Is_Limited_Type (Formal_Type)
8099 (Underlying_Type (Formal_Type)))))
8101 Set_Extra_Constrained
8102 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8106 -- Create extra formal for supporting accessibility checking. This
8107 -- is done for both anonymous access formals and formals of named
8108 -- access types that are marked as controlling formals. The latter
8109 -- case can occur when Expand_Dispatching_Call creates a subprogram
8110 -- type and substitutes the types of access-to-class-wide actuals
8111 -- for the anonymous access-to-specific-type of controlling formals.
8112 -- Base_Type is applied because in cases where there is a null
8113 -- exclusion the formal may have an access subtype.
8115 -- This is suppressed if we specifically suppress accessibility
8116 -- checks at the package level for either the subprogram, or the
8117 -- package in which it resides. However, we do not suppress it
8118 -- simply if the scope has accessibility checks suppressed, since
8119 -- this could cause trouble when clients are compiled with a
8120 -- different suppression setting. The explicit checks at the
8121 -- package level are safe from this point of view.
8123 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8124 or else (Is_Controlling_Formal (Formal)
8125 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8127 (Explicit_Suppress (E, Accessibility_Check)
8129 Explicit_Suppress (Scope (E), Accessibility_Check))
8132 or else Present (Extra_Accessibility (P_Formal)))
8134 Set_Extra_Accessibility
8135 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8138 -- This label is required when skipping extra formal generation for
8139 -- Unchecked_Union parameters.
8141 <<Skip_Extra_Formal_Generation>>
8143 if Present (P_Formal) then
8144 Next_Formal (P_Formal);
8147 Next_Formal (Formal);
8150 <<Test_For_Func_Result_Extras>>
8152 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8153 -- function call is ... determined by the point of call ...".
8155 if Needs_Result_Accessibility_Level (E) then
8156 Set_Extra_Accessibility_Of_Result
8157 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8160 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8161 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8163 if Is_Build_In_Place_Function (E) then
8165 Result_Subt : constant Entity_Id := Etype (E);
8166 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8167 Formal_Typ : Entity_Id;
8168 Subp_Decl : Node_Id;
8169 Discard : Entity_Id;
8172 -- In the case of functions with unconstrained result subtypes,
8173 -- add a 4-state formal indicating whether the return object is
8174 -- allocated by the caller (1), or should be allocated by the
8175 -- callee on the secondary stack (2), in the global heap (3), or
8176 -- in a user-defined storage pool (4). For the moment we just use
8177 -- Natural for the type of this formal. Note that this formal
8178 -- isn't usually needed in the case where the result subtype is
8179 -- constrained, but it is needed when the function has a tagged
8180 -- result, because generally such functions can be called in a
8181 -- dispatching context and such calls must be handled like calls
8182 -- to a class-wide function.
8184 if Needs_BIP_Alloc_Form (E) then
8187 (E, Standard_Natural,
8188 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8190 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8191 -- use a user-defined pool. This formal is not added on
8192 -- ZFP as those targets do not support pools.
8194 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8197 (E, RTE (RE_Root_Storage_Pool_Ptr),
8198 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8202 -- In the case of functions whose result type needs finalization,
8203 -- add an extra formal which represents the finalization master.
8205 if Needs_BIP_Finalization_Master (E) then
8208 (E, RTE (RE_Finalization_Master_Ptr),
8209 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8212 -- When the result type contains tasks, add two extra formals: the
8213 -- master of the tasks to be created, and the caller's activation
8216 if Has_Task (Full_Subt) then
8219 (E, RTE (RE_Master_Id),
8220 E, BIP_Formal_Suffix (BIP_Task_Master));
8223 (E, RTE (RE_Activation_Chain_Access),
8224 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8227 -- All build-in-place functions get an extra formal that will be
8228 -- passed the address of the return object within the caller.
8231 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8233 -- Incomplete_View_From_Limited_With is needed here because
8234 -- gigi gets confused if the designated type is the full view
8235 -- coming from a limited-with'ed package. In the normal case,
8236 -- (no limited with) Incomplete_View_From_Limited_With
8237 -- returns Result_Subt.
8239 Set_Directly_Designated_Type
8240 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8241 Set_Etype (Formal_Typ, Formal_Typ);
8242 Set_Depends_On_Private
8243 (Formal_Typ, Has_Private_Component (Formal_Typ));
8244 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8245 Set_Is_Access_Constant (Formal_Typ, False);
8247 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8248 -- the designated type comes from the limited view (for back-end
8251 Set_From_Limited_With
8252 (Formal_Typ, From_Limited_With (Result_Subt));
8254 Layout_Type (Formal_Typ);
8256 -- Force the definition of the Itype in case of internal function
8257 -- calls within the same or nested scope.
8259 if Is_Subprogram_Or_Generic_Subprogram (E) then
8260 Subp_Decl := Parent (E);
8262 -- The insertion point for an Itype reference should be after
8263 -- the unit declaration node of the subprogram. An exception
8264 -- to this are inherited operations from a parent type in which
8265 -- case the derived type acts as their parent.
8267 if Nkind_In (Subp_Decl, N_Function_Specification,
8268 N_Procedure_Specification)
8270 Subp_Decl := Parent (Subp_Decl);
8273 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8278 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8282 -- If this is an instance of a generic, we need to have extra formals
8285 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8286 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8288 end Create_Extra_Formals;
8290 -----------------------------
8291 -- Enter_Overloaded_Entity --
8292 -----------------------------
8294 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8295 function Matches_Predefined_Op return Boolean;
8296 -- This returns an approximation of whether S matches a predefined
8297 -- operator, based on the operator symbol, and the parameter and result
8298 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8300 ---------------------------
8301 -- Matches_Predefined_Op --
8302 ---------------------------
8304 function Matches_Predefined_Op return Boolean is
8305 Formal_1 : constant Entity_Id := First_Formal (S);
8306 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8307 Op : constant Name_Id := Chars (S);
8308 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8309 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8314 if Present (Formal_2) then
8316 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8319 -- All but "&" and "**" have same-types parameters
8328 if Type_1 /= Type_2 then
8333 -- Check parameter and result types
8341 Is_Boolean_Type (Result_Type)
8342 and then Result_Type = Type_1;
8348 Is_Integer_Type (Result_Type)
8349 and then Result_Type = Type_1;
8357 Is_Numeric_Type (Result_Type)
8358 and then Result_Type = Type_1;
8364 Is_Boolean_Type (Result_Type)
8365 and then not Is_Limited_Type (Type_1);
8373 Is_Boolean_Type (Result_Type)
8374 and then (Is_Array_Type (Type_1)
8375 or else Is_Scalar_Type (Type_1));
8377 when Name_Op_Concat =>
8378 return Is_Array_Type (Result_Type);
8380 when Name_Op_Expon =>
8382 (Is_Integer_Type (Result_Type)
8383 or else Is_Floating_Point_Type (Result_Type))
8384 and then Result_Type = Type_1
8385 and then Type_2 = Standard_Integer;
8388 raise Program_Error;
8401 Is_Numeric_Type (Result_Type)
8402 and then Result_Type = Type_1;
8406 Is_Boolean_Type (Result_Type)
8407 and then Result_Type = Type_1;
8410 raise Program_Error;
8413 end Matches_Predefined_Op;
8417 E : Entity_Id := Current_Entity_In_Scope (S);
8418 C_E : Entity_Id := Current_Entity (S);
8420 -- Start of processing for Enter_Overloaded_Entity
8424 Set_Has_Homonym (E);
8425 Set_Has_Homonym (S);
8428 Set_Is_Immediately_Visible (S);
8429 Set_Scope (S, Current_Scope);
8431 -- Chain new entity if front of homonym in current scope, so that
8432 -- homonyms are contiguous.
8434 if Present (E) and then E /= C_E then
8435 while Homonym (C_E) /= E loop
8436 C_E := Homonym (C_E);
8439 Set_Homonym (C_E, S);
8443 Set_Current_Entity (S);
8448 if Is_Inherited_Operation (S) then
8449 Append_Inherited_Subprogram (S);
8451 Append_Entity (S, Current_Scope);
8454 Set_Public_Status (S);
8456 if Debug_Flag_E then
8457 Write_Str ("New overloaded entity chain: ");
8458 Write_Name (Chars (S));
8461 while Present (E) loop
8462 Write_Str (" "); Write_Int (Int (E));
8469 -- Generate warning for hiding
8472 and then Comes_From_Source (S)
8473 and then In_Extended_Main_Source_Unit (S)
8480 -- Warn unless genuine overloading. Do not emit warning on
8481 -- hiding predefined operators in Standard (these are either an
8482 -- (artifact of our implicit declarations, or simple noise) but
8483 -- keep warning on a operator defined on a local subtype, because
8484 -- of the real danger that different operators may be applied in
8485 -- various parts of the program.
8487 -- Note that if E and S have the same scope, there is never any
8488 -- hiding. Either the two conflict, and the program is illegal,
8489 -- or S is overriding an implicit inherited subprogram.
8491 if Scope (E) /= Scope (S)
8492 and then (not Is_Overloadable (E)
8493 or else Subtype_Conformant (E, S))
8494 and then (Is_Immediately_Visible (E)
8495 or else Is_Potentially_Use_Visible (S))
8497 if Scope (E) = Standard_Standard then
8498 if Nkind (S) = N_Defining_Operator_Symbol
8499 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8501 and then Matches_Predefined_Op
8504 ("declaration of & hides predefined operator?h?", S);
8507 -- E not immediately within Standard
8510 Error_Msg_Sloc := Sloc (E);
8511 Error_Msg_N ("declaration of & hides one #?h?", S);
8516 end Enter_Overloaded_Entity;
8518 -----------------------------
8519 -- Check_Untagged_Equality --
8520 -----------------------------
8522 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8523 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8524 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8528 -- This check applies only if we have a subprogram declaration with an
8529 -- untagged record type.
8531 if Nkind (Decl) /= N_Subprogram_Declaration
8532 or else not Is_Record_Type (Typ)
8533 or else Is_Tagged_Type (Typ)
8538 -- In Ada 2012 case, we will output errors or warnings depending on
8539 -- the setting of debug flag -gnatd.E.
8541 if Ada_Version >= Ada_2012 then
8542 Error_Msg_Warn := Debug_Flag_Dot_EE;
8544 -- In earlier versions of Ada, nothing to do unless we are warning on
8545 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8548 if not Warn_On_Ada_2012_Compatibility then
8553 -- Cases where the type has already been frozen
8555 if Is_Frozen (Typ) then
8557 -- If the type is not declared in a package, or if we are in the body
8558 -- of the package or in some other scope, the new operation is not
8559 -- primitive, and therefore legal, though suspicious. Should we
8560 -- generate a warning in this case ???
8562 if Ekind (Scope (Typ)) /= E_Package
8563 or else Scope (Typ) /= Current_Scope
8567 -- If the type is a generic actual (sub)type, the operation is not
8568 -- primitive either because the base type is declared elsewhere.
8570 elsif Is_Generic_Actual_Type (Typ) then
8573 -- Here we have a definite error of declaration after freezing
8576 if Ada_Version >= Ada_2012 then
8578 ("equality operator must be declared before type & is "
8579 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8581 -- In Ada 2012 mode with error turned to warning, output one
8582 -- more warning to warn that the equality operation may not
8583 -- compose. This is the consequence of ignoring the error.
8585 if Error_Msg_Warn then
8586 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8591 ("equality operator must be declared before type& is "
8592 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8595 -- If we are in the package body, we could just move the
8596 -- declaration to the package spec, so add a message saying that.
8598 if In_Package_Body (Scope (Typ)) then
8599 if Ada_Version >= Ada_2012 then
8601 ("\move declaration to package spec<<", Eq_Op);
8604 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8607 -- Otherwise try to find the freezing point
8610 Obj_Decl := Next (Parent (Typ));
8611 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8612 if Nkind (Obj_Decl) = N_Object_Declaration
8613 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8615 -- Freezing point, output warnings
8617 if Ada_Version >= Ada_2012 then
8619 ("type& is frozen by declaration??", Obj_Decl, Typ);
8621 ("\an equality operator cannot be declared after "
8626 ("type& is frozen by declaration (Ada 2012)?y?",
8629 ("\an equality operator cannot be declared after "
8630 & "this point (Ada 2012)?y?",
8642 -- Here if type is not frozen yet. It is illegal to have a primitive
8643 -- equality declared in the private part if the type is visible.
8645 elsif not In_Same_List (Parent (Typ), Decl)
8646 and then not Is_Limited_Type (Typ)
8648 -- Shouldn't we give an RM reference here???
8650 if Ada_Version >= Ada_2012 then
8652 ("equality operator appears too late<<", Eq_Op);
8655 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8658 -- No error detected
8663 end Check_Untagged_Equality;
8665 -----------------------------
8666 -- Find_Corresponding_Spec --
8667 -----------------------------
8669 function Find_Corresponding_Spec
8671 Post_Error : Boolean := True) return Entity_Id
8673 Spec : constant Node_Id := Specification (N);
8674 Designator : constant Entity_Id := Defining_Entity (Spec);
8678 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8679 -- Even if fully conformant, a body may depend on a generic actual when
8680 -- the spec does not, or vice versa, in which case they were distinct
8681 -- entities in the generic.
8683 -------------------------------
8684 -- Different_Generic_Profile --
8685 -------------------------------
8687 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8690 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8691 -- Check that the types of corresponding formals have the same
8692 -- generic actual if any. We have to account for subtypes of a
8693 -- generic formal, declared between a spec and a body, which may
8694 -- appear distinct in an instance but matched in the generic, and
8695 -- the subtype may be used either in the spec or the body of the
8696 -- subprogram being checked.
8698 -------------------------
8699 -- Same_Generic_Actual --
8700 -------------------------
8702 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8704 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8705 -- Predicate to check whether S1 is a subtype of S2 in the source
8708 -------------------------
8709 -- Is_Declared_Subtype --
8710 -------------------------
8712 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8714 return Comes_From_Source (Parent (S1))
8715 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8716 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8717 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8718 end Is_Declared_Subtype;
8720 -- Start of processing for Same_Generic_Actual
8723 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8724 or else Is_Declared_Subtype (T1, T2)
8725 or else Is_Declared_Subtype (T2, T1);
8726 end Same_Generic_Actual;
8728 -- Start of processing for Different_Generic_Profile
8731 if not In_Instance then
8734 elsif Ekind (E) = E_Function
8735 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8740 F1 := First_Formal (Designator);
8741 F2 := First_Formal (E);
8742 while Present (F1) loop
8743 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8752 end Different_Generic_Profile;
8754 -- Start of processing for Find_Corresponding_Spec
8757 E := Current_Entity (Designator);
8758 while Present (E) loop
8760 -- We are looking for a matching spec. It must have the same scope,
8761 -- and the same name, and either be type conformant, or be the case
8762 -- of a library procedure spec and its body (which belong to one
8763 -- another regardless of whether they are type conformant or not).
8765 if Scope (E) = Current_Scope then
8766 if Current_Scope = Standard_Standard
8767 or else (Ekind (E) = Ekind (Designator)
8768 and then Type_Conformant (E, Designator))
8770 -- Within an instantiation, we know that spec and body are
8771 -- subtype conformant, because they were subtype conformant in
8772 -- the generic. We choose the subtype-conformant entity here as
8773 -- well, to resolve spurious ambiguities in the instance that
8774 -- were not present in the generic (i.e. when two different
8775 -- types are given the same actual). If we are looking for a
8776 -- spec to match a body, full conformance is expected.
8780 -- Inherit the convention and "ghostness" of the matching
8781 -- spec to ensure proper full and subtype conformance.
8783 Set_Convention (Designator, Convention (E));
8785 -- Skip past subprogram bodies and subprogram renamings that
8786 -- may appear to have a matching spec, but that aren't fully
8787 -- conformant with it. That can occur in cases where an
8788 -- actual type causes unrelated homographs in the instance.
8790 if Nkind_In (N, N_Subprogram_Body,
8791 N_Subprogram_Renaming_Declaration)
8792 and then Present (Homonym (E))
8793 and then not Fully_Conformant (Designator, E)
8797 elsif not Subtype_Conformant (Designator, E) then
8800 elsif Different_Generic_Profile (E) then
8805 -- Ada 2012 (AI05-0165): For internally generated bodies of
8806 -- null procedures locate the internally generated spec. We
8807 -- enforce mode conformance since a tagged type may inherit
8808 -- from interfaces several null primitives which differ only
8809 -- in the mode of the formals.
8811 if not (Comes_From_Source (E))
8812 and then Is_Null_Procedure (E)
8813 and then not Mode_Conformant (Designator, E)
8817 -- For null procedures coming from source that are completions,
8818 -- analysis of the generated body will establish the link.
8820 elsif Comes_From_Source (E)
8821 and then Nkind (Spec) = N_Procedure_Specification
8822 and then Null_Present (Spec)
8826 -- Expression functions can be completions, but cannot be
8827 -- completed by an explicit body.
8829 elsif Comes_From_Source (E)
8830 and then Comes_From_Source (N)
8831 and then Nkind (N) = N_Subprogram_Body
8832 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8833 N_Expression_Function
8835 Error_Msg_Sloc := Sloc (E);
8836 Error_Msg_N ("body conflicts with expression function#", N);
8839 elsif not Has_Completion (E) then
8840 if Nkind (N) /= N_Subprogram_Body_Stub then
8841 Set_Corresponding_Spec (N, E);
8844 Set_Has_Completion (E);
8847 elsif Nkind (Parent (N)) = N_Subunit then
8849 -- If this is the proper body of a subunit, the completion
8850 -- flag is set when analyzing the stub.
8854 -- If E is an internal function with a controlling result that
8855 -- was created for an operation inherited by a null extension,
8856 -- it may be overridden by a body without a previous spec (one
8857 -- more reason why these should be shunned). In that case we
8858 -- remove the generated body if present, because the current
8859 -- one is the explicit overriding.
8861 elsif Ekind (E) = E_Function
8862 and then Ada_Version >= Ada_2005
8863 and then not Comes_From_Source (E)
8864 and then Has_Controlling_Result (E)
8865 and then Is_Null_Extension (Etype (E))
8866 and then Comes_From_Source (Spec)
8868 Set_Has_Completion (E, False);
8871 and then Nkind (Parent (E)) = N_Function_Specification
8874 (Unit_Declaration_Node
8875 (Corresponding_Body (Unit_Declaration_Node (E))));
8879 -- If expansion is disabled, or if the wrapper function has
8880 -- not been generated yet, this a late body overriding an
8881 -- inherited operation, or it is an overriding by some other
8882 -- declaration before the controlling result is frozen. In
8883 -- either case this is a declaration of a new entity.
8889 -- If the body already exists, then this is an error unless
8890 -- the previous declaration is the implicit declaration of a
8891 -- derived subprogram. It is also legal for an instance to
8892 -- contain type conformant overloadable declarations (but the
8893 -- generic declaration may not), per 8.3(26/2).
8895 elsif No (Alias (E))
8896 and then not Is_Intrinsic_Subprogram (E)
8897 and then not In_Instance
8900 Error_Msg_Sloc := Sloc (E);
8902 if Is_Imported (E) then
8904 ("body not allowed for imported subprogram & declared#",
8907 Error_Msg_NE ("duplicate body for & declared#", N, E);
8911 -- Child units cannot be overloaded, so a conformance mismatch
8912 -- between body and a previous spec is an error.
8914 elsif Is_Child_Unit (E)
8916 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8918 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8923 ("body of child unit does not match previous declaration", N);
8931 -- On exit, we know that no previous declaration of subprogram exists
8934 end Find_Corresponding_Spec;
8936 ----------------------
8937 -- Fully_Conformant --
8938 ----------------------
8940 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8943 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8945 end Fully_Conformant;
8947 ----------------------------------
8948 -- Fully_Conformant_Expressions --
8949 ----------------------------------
8951 function Fully_Conformant_Expressions
8952 (Given_E1 : Node_Id;
8953 Given_E2 : Node_Id) return Boolean
8955 E1 : constant Node_Id := Original_Node (Given_E1);
8956 E2 : constant Node_Id := Original_Node (Given_E2);
8957 -- We always test conformance on original nodes, since it is possible
8958 -- for analysis and/or expansion to make things look as though they
8959 -- conform when they do not, e.g. by converting 1+2 into 3.
8961 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8962 renames Fully_Conformant_Expressions;
8964 function FCL (L1, L2 : List_Id) return Boolean;
8965 -- Compare elements of two lists for conformance. Elements have to be
8966 -- conformant, and actuals inserted as default parameters do not match
8967 -- explicit actuals with the same value.
8969 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8970 -- Compare an operator node with a function call
8976 function FCL (L1, L2 : List_Id) return Boolean is
8980 if L1 = No_List then
8986 if L2 = No_List then
8992 -- Compare two lists, skipping rewrite insertions (we want to compare
8993 -- the original trees, not the expanded versions).
8996 if Is_Rewrite_Insertion (N1) then
8998 elsif Is_Rewrite_Insertion (N2) then
9004 elsif not FCE (N1, N2) then
9017 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
9018 Actuals : constant List_Id := Parameter_Associations (Call_Node);
9023 or else Entity (Op_Node) /= Entity (Name (Call_Node))
9028 Act := First (Actuals);
9030 if Nkind (Op_Node) in N_Binary_Op then
9031 if not FCE (Left_Opnd (Op_Node), Act) then
9038 return Present (Act)
9039 and then FCE (Right_Opnd (Op_Node), Act)
9040 and then No (Next (Act));
9044 -- Start of processing for Fully_Conformant_Expressions
9047 -- Nonconformant if paren count does not match. Note: if some idiot
9048 -- complains that we don't do this right for more than 3 levels of
9049 -- parentheses, they will be treated with the respect they deserve.
9051 if Paren_Count (E1) /= Paren_Count (E2) then
9054 -- If same entities are referenced, then they are conformant even if
9055 -- they have different forms (RM 8.3.1(19-20)).
9057 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
9058 if Present (Entity (E1)) then
9059 return Entity (E1) = Entity (E2)
9061 -- One may be a discriminant that has been replaced by the
9062 -- corresponding discriminal.
9065 (Chars (Entity (E1)) = Chars (Entity (E2))
9066 and then Ekind (Entity (E1)) = E_Discriminant
9067 and then Ekind (Entity (E2)) = E_In_Parameter)
9069 -- The discriminant of a protected type is transformed into
9070 -- a local constant and then into a parameter of a protected
9074 (Ekind (Entity (E1)) = E_Constant
9075 and then Ekind (Entity (E2)) = E_In_Parameter
9076 and then Present (Discriminal_Link (Entity (E1)))
9077 and then Discriminal_Link (Entity (E1)) =
9078 Discriminal_Link (Entity (E2)))
9080 -- AI12-050: The loop variables of quantified expressions
9081 -- match if they have the same identifier, even though they
9082 -- are different entities.
9085 (Chars (Entity (E1)) = Chars (Entity (E2))
9086 and then Ekind (Entity (E1)) = E_Loop_Parameter
9087 and then Ekind (Entity (E2)) = E_Loop_Parameter);
9089 elsif Nkind (E1) = N_Expanded_Name
9090 and then Nkind (E2) = N_Expanded_Name
9091 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9092 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9094 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9097 -- Identifiers in component associations don't always have
9098 -- entities, but their names must conform.
9100 return Nkind (E1) = N_Identifier
9101 and then Nkind (E2) = N_Identifier
9102 and then Chars (E1) = Chars (E2);
9105 elsif Nkind (E1) = N_Character_Literal
9106 and then Nkind (E2) = N_Expanded_Name
9108 return Nkind (Selector_Name (E2)) = N_Character_Literal
9109 and then Chars (E1) = Chars (Selector_Name (E2));
9111 elsif Nkind (E2) = N_Character_Literal
9112 and then Nkind (E1) = N_Expanded_Name
9114 return Nkind (Selector_Name (E1)) = N_Character_Literal
9115 and then Chars (E2) = Chars (Selector_Name (E1));
9117 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9118 return FCO (E1, E2);
9120 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9121 return FCO (E2, E1);
9123 -- Otherwise we must have the same syntactic entity
9125 elsif Nkind (E1) /= Nkind (E2) then
9128 -- At this point, we specialize by node type
9134 FCL (Expressions (E1), Expressions (E2))
9136 FCL (Component_Associations (E1),
9137 Component_Associations (E2));
9140 if Nkind (Expression (E1)) = N_Qualified_Expression
9142 Nkind (Expression (E2)) = N_Qualified_Expression
9144 return FCE (Expression (E1), Expression (E2));
9146 -- Check that the subtype marks and any constraints
9151 Indic1 : constant Node_Id := Expression (E1);
9152 Indic2 : constant Node_Id := Expression (E2);
9157 if Nkind (Indic1) /= N_Subtype_Indication then
9159 Nkind (Indic2) /= N_Subtype_Indication
9160 and then Entity (Indic1) = Entity (Indic2);
9162 elsif Nkind (Indic2) /= N_Subtype_Indication then
9164 Nkind (Indic1) /= N_Subtype_Indication
9165 and then Entity (Indic1) = Entity (Indic2);
9168 if Entity (Subtype_Mark (Indic1)) /=
9169 Entity (Subtype_Mark (Indic2))
9174 Elt1 := First (Constraints (Constraint (Indic1)));
9175 Elt2 := First (Constraints (Constraint (Indic2)));
9176 while Present (Elt1) and then Present (Elt2) loop
9177 if not FCE (Elt1, Elt2) then
9190 when N_Attribute_Reference =>
9192 Attribute_Name (E1) = Attribute_Name (E2)
9193 and then FCL (Expressions (E1), Expressions (E2));
9197 Entity (E1) = Entity (E2)
9198 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9199 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9201 when N_Membership_Test
9205 FCE (Left_Opnd (E1), Left_Opnd (E2))
9207 FCE (Right_Opnd (E1), Right_Opnd (E2));
9209 when N_Case_Expression =>
9215 if not FCE (Expression (E1), Expression (E2)) then
9219 Alt1 := First (Alternatives (E1));
9220 Alt2 := First (Alternatives (E2));
9222 if Present (Alt1) /= Present (Alt2) then
9224 elsif No (Alt1) then
9228 if not FCE (Expression (Alt1), Expression (Alt2))
9229 or else not FCL (Discrete_Choices (Alt1),
9230 Discrete_Choices (Alt2))
9241 when N_Character_Literal =>
9243 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9245 when N_Component_Association =>
9247 FCL (Choices (E1), Choices (E2))
9249 FCE (Expression (E1), Expression (E2));
9251 when N_Explicit_Dereference =>
9253 FCE (Prefix (E1), Prefix (E2));
9255 when N_Extension_Aggregate =>
9257 FCL (Expressions (E1), Expressions (E2))
9258 and then Null_Record_Present (E1) =
9259 Null_Record_Present (E2)
9260 and then FCL (Component_Associations (E1),
9261 Component_Associations (E2));
9263 when N_Function_Call =>
9265 FCE (Name (E1), Name (E2))
9267 FCL (Parameter_Associations (E1),
9268 Parameter_Associations (E2));
9270 when N_If_Expression =>
9272 FCL (Expressions (E1), Expressions (E2));
9274 when N_Indexed_Component =>
9276 FCE (Prefix (E1), Prefix (E2))
9278 FCL (Expressions (E1), Expressions (E2));
9280 when N_Integer_Literal =>
9281 return (Intval (E1) = Intval (E2));
9286 when N_Operator_Symbol =>
9288 Chars (E1) = Chars (E2);
9290 when N_Others_Choice =>
9293 when N_Parameter_Association =>
9295 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9296 and then FCE (Explicit_Actual_Parameter (E1),
9297 Explicit_Actual_Parameter (E2));
9299 when N_Qualified_Expression
9301 | N_Unchecked_Type_Conversion
9304 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9306 FCE (Expression (E1), Expression (E2));
9308 when N_Quantified_Expression =>
9309 if not FCE (Condition (E1), Condition (E2)) then
9313 if Present (Loop_Parameter_Specification (E1))
9314 and then Present (Loop_Parameter_Specification (E2))
9317 L1 : constant Node_Id :=
9318 Loop_Parameter_Specification (E1);
9319 L2 : constant Node_Id :=
9320 Loop_Parameter_Specification (E2);
9324 Reverse_Present (L1) = Reverse_Present (L2)
9326 FCE (Defining_Identifier (L1),
9327 Defining_Identifier (L2))
9329 FCE (Discrete_Subtype_Definition (L1),
9330 Discrete_Subtype_Definition (L2));
9333 elsif Present (Iterator_Specification (E1))
9334 and then Present (Iterator_Specification (E2))
9337 I1 : constant Node_Id := Iterator_Specification (E1);
9338 I2 : constant Node_Id := Iterator_Specification (E2);
9342 FCE (Defining_Identifier (I1),
9343 Defining_Identifier (I2))
9345 Of_Present (I1) = Of_Present (I2)
9347 Reverse_Present (I1) = Reverse_Present (I2)
9348 and then FCE (Name (I1), Name (I2))
9349 and then FCE (Subtype_Indication (I1),
9350 Subtype_Indication (I2));
9353 -- The quantified expressions used different specifications to
9354 -- walk their respective ranges.
9362 FCE (Low_Bound (E1), Low_Bound (E2))
9364 FCE (High_Bound (E1), High_Bound (E2));
9366 when N_Real_Literal =>
9367 return (Realval (E1) = Realval (E2));
9369 when N_Selected_Component =>
9371 FCE (Prefix (E1), Prefix (E2))
9373 FCE (Selector_Name (E1), Selector_Name (E2));
9377 FCE (Prefix (E1), Prefix (E2))
9379 FCE (Discrete_Range (E1), Discrete_Range (E2));
9381 when N_String_Literal =>
9383 S1 : constant String_Id := Strval (E1);
9384 S2 : constant String_Id := Strval (E2);
9385 L1 : constant Nat := String_Length (S1);
9386 L2 : constant Nat := String_Length (S2);
9393 for J in 1 .. L1 loop
9394 if Get_String_Char (S1, J) /=
9395 Get_String_Char (S2, J)
9407 Entity (E1) = Entity (E2)
9409 FCE (Right_Opnd (E1), Right_Opnd (E2));
9411 -- All other node types cannot appear in this context. Strictly
9412 -- we should raise a fatal internal error. Instead we just ignore
9413 -- the nodes. This means that if anyone makes a mistake in the
9414 -- expander and mucks an expression tree irretrievably, the result
9415 -- will be a failure to detect a (probably very obscure) case
9416 -- of non-conformance, which is better than bombing on some
9417 -- case where two expressions do in fact conform.
9423 end Fully_Conformant_Expressions;
9425 ----------------------------------------
9426 -- Fully_Conformant_Discrete_Subtypes --
9427 ----------------------------------------
9429 function Fully_Conformant_Discrete_Subtypes
9430 (Given_S1 : Node_Id;
9431 Given_S2 : Node_Id) return Boolean
9433 S1 : constant Node_Id := Original_Node (Given_S1);
9434 S2 : constant Node_Id := Original_Node (Given_S2);
9436 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9437 -- Special-case for a bound given by a discriminant, which in the body
9438 -- is replaced with the discriminal of the enclosing type.
9440 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9441 -- Check both bounds
9443 -----------------------
9444 -- Conforming_Bounds --
9445 -----------------------
9447 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9449 if Is_Entity_Name (B1)
9450 and then Is_Entity_Name (B2)
9451 and then Ekind (Entity (B1)) = E_Discriminant
9453 return Chars (B1) = Chars (B2);
9456 return Fully_Conformant_Expressions (B1, B2);
9458 end Conforming_Bounds;
9460 -----------------------
9461 -- Conforming_Ranges --
9462 -----------------------
9464 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9467 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9469 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9470 end Conforming_Ranges;
9472 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9475 if Nkind (S1) /= Nkind (S2) then
9478 elsif Is_Entity_Name (S1) then
9479 return Entity (S1) = Entity (S2);
9481 elsif Nkind (S1) = N_Range then
9482 return Conforming_Ranges (S1, S2);
9484 elsif Nkind (S1) = N_Subtype_Indication then
9486 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9489 (Range_Expression (Constraint (S1)),
9490 Range_Expression (Constraint (S2)));
9494 end Fully_Conformant_Discrete_Subtypes;
9496 --------------------
9497 -- Install_Entity --
9498 --------------------
9500 procedure Install_Entity (E : Entity_Id) is
9501 Prev : constant Entity_Id := Current_Entity (E);
9503 Set_Is_Immediately_Visible (E);
9504 Set_Current_Entity (E);
9505 Set_Homonym (E, Prev);
9508 ---------------------
9509 -- Install_Formals --
9510 ---------------------
9512 procedure Install_Formals (Id : Entity_Id) is
9515 F := First_Formal (Id);
9516 while Present (F) loop
9520 end Install_Formals;
9522 -----------------------------
9523 -- Is_Interface_Conformant --
9524 -----------------------------
9526 function Is_Interface_Conformant
9527 (Tagged_Type : Entity_Id;
9528 Iface_Prim : Entity_Id;
9529 Prim : Entity_Id) return Boolean
9531 -- The operation may in fact be an inherited (implicit) operation
9532 -- rather than the original interface primitive, so retrieve the
9533 -- ultimate ancestor.
9535 Iface : constant Entity_Id :=
9536 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9537 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9539 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9540 -- Return the controlling formal of Prim
9542 ------------------------
9543 -- Controlling_Formal --
9544 ------------------------
9546 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9550 E := First_Entity (Prim);
9551 while Present (E) loop
9552 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9560 end Controlling_Formal;
9564 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9565 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9567 -- Start of processing for Is_Interface_Conformant
9570 pragma Assert (Is_Subprogram (Iface_Prim)
9571 and then Is_Subprogram (Prim)
9572 and then Is_Dispatching_Operation (Iface_Prim)
9573 and then Is_Dispatching_Operation (Prim));
9575 pragma Assert (Is_Interface (Iface)
9576 or else (Present (Alias (Iface_Prim))
9579 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9581 if Prim = Iface_Prim
9582 or else not Is_Subprogram (Prim)
9583 or else Ekind (Prim) /= Ekind (Iface_Prim)
9584 or else not Is_Dispatching_Operation (Prim)
9585 or else Scope (Prim) /= Scope (Tagged_Type)
9587 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9588 or else not Primitive_Names_Match (Iface_Prim, Prim)
9592 -- The mode of the controlling formals must match
9594 elsif Present (Iface_Ctrl_F)
9595 and then Present (Prim_Ctrl_F)
9596 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9600 -- Case of a procedure, or a function whose result type matches the
9601 -- result type of the interface primitive, or a function that has no
9602 -- controlling result (I or access I).
9604 elsif Ekind (Iface_Prim) = E_Procedure
9605 or else Etype (Prim) = Etype (Iface_Prim)
9606 or else not Has_Controlling_Result (Prim)
9608 return Type_Conformant
9609 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9611 -- Case of a function returning an interface, or an access to one. Check
9612 -- that the return types correspond.
9614 elsif Implements_Interface (Typ, Iface) then
9615 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9617 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9622 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9623 Skip_Controlling_Formals => True);
9629 end Is_Interface_Conformant;
9631 ---------------------------------
9632 -- Is_Non_Overriding_Operation --
9633 ---------------------------------
9635 function Is_Non_Overriding_Operation
9636 (Prev_E : Entity_Id;
9637 New_E : Entity_Id) return Boolean
9641 G_Typ : Entity_Id := Empty;
9643 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9644 -- If F_Type is a derived type associated with a generic actual subtype,
9645 -- then return its Generic_Parent_Type attribute, else return Empty.
9647 function Types_Correspond
9648 (P_Type : Entity_Id;
9649 N_Type : Entity_Id) return Boolean;
9650 -- Returns true if and only if the types (or designated types in the
9651 -- case of anonymous access types) are the same or N_Type is derived
9652 -- directly or indirectly from P_Type.
9654 -----------------------------
9655 -- Get_Generic_Parent_Type --
9656 -----------------------------
9658 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9664 if Is_Derived_Type (F_Typ)
9665 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9667 -- The tree must be traversed to determine the parent subtype in
9668 -- the generic unit, which unfortunately isn't always available
9669 -- via semantic attributes. ??? (Note: The use of Original_Node
9670 -- is needed for cases where a full derived type has been
9673 -- If the parent type is a scalar type, the derivation creates
9674 -- an anonymous base type for it, and the source type is its
9677 if Is_Scalar_Type (F_Typ)
9678 and then not Comes_From_Source (F_Typ)
9682 (Original_Node (Parent (First_Subtype (F_Typ))));
9684 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9686 if Nkind (Defn) = N_Derived_Type_Definition then
9687 Indic := Subtype_Indication (Defn);
9689 if Nkind (Indic) = N_Subtype_Indication then
9690 G_Typ := Entity (Subtype_Mark (Indic));
9692 G_Typ := Entity (Indic);
9695 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9696 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9698 return Generic_Parent_Type (Parent (G_Typ));
9704 end Get_Generic_Parent_Type;
9706 ----------------------
9707 -- Types_Correspond --
9708 ----------------------
9710 function Types_Correspond
9711 (P_Type : Entity_Id;
9712 N_Type : Entity_Id) return Boolean
9714 Prev_Type : Entity_Id := Base_Type (P_Type);
9715 New_Type : Entity_Id := Base_Type (N_Type);
9718 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9719 Prev_Type := Designated_Type (Prev_Type);
9722 if Ekind (New_Type) = E_Anonymous_Access_Type then
9723 New_Type := Designated_Type (New_Type);
9726 if Prev_Type = New_Type then
9729 elsif not Is_Class_Wide_Type (New_Type) then
9730 while Etype (New_Type) /= New_Type loop
9731 New_Type := Etype (New_Type);
9733 if New_Type = Prev_Type then
9739 end Types_Correspond;
9741 -- Start of processing for Is_Non_Overriding_Operation
9744 -- In the case where both operations are implicit derived subprograms
9745 -- then neither overrides the other. This can only occur in certain
9746 -- obscure cases (e.g., derivation from homographs created in a generic
9749 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9752 elsif Ekind (Current_Scope) = E_Package
9753 and then Is_Generic_Instance (Current_Scope)
9754 and then In_Private_Part (Current_Scope)
9755 and then Comes_From_Source (New_E)
9757 -- We examine the formals and result type of the inherited operation,
9758 -- to determine whether their type is derived from (the instance of)
9759 -- a generic type. The first such formal or result type is the one
9762 Formal := First_Formal (Prev_E);
9764 while Present (Formal) loop
9765 F_Typ := Base_Type (Etype (Formal));
9767 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9768 F_Typ := Designated_Type (F_Typ);
9771 G_Typ := Get_Generic_Parent_Type (F_Typ);
9772 exit when Present (G_Typ);
9774 Next_Formal (Formal);
9777 -- If the function dispatches on result check the result type
9779 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9780 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9787 -- If the generic type is a private type, then the original operation
9788 -- was not overriding in the generic, because there was no primitive
9789 -- operation to override.
9791 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9792 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9793 N_Formal_Private_Type_Definition
9797 -- The generic parent type is the ancestor of a formal derived
9798 -- type declaration. We need to check whether it has a primitive
9799 -- operation that should be overridden by New_E in the generic.
9803 P_Formal : Entity_Id;
9804 N_Formal : Entity_Id;
9808 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9811 while Present (Prim_Elt) loop
9812 P_Prim := Node (Prim_Elt);
9814 if Chars (P_Prim) = Chars (New_E)
9815 and then Ekind (P_Prim) = Ekind (New_E)
9817 P_Formal := First_Formal (P_Prim);
9818 N_Formal := First_Formal (New_E);
9819 while Present (P_Formal) and then Present (N_Formal) loop
9820 P_Typ := Etype (P_Formal);
9821 N_Typ := Etype (N_Formal);
9823 if not Types_Correspond (P_Typ, N_Typ) then
9827 Next_Entity (P_Formal);
9828 Next_Entity (N_Formal);
9831 -- Found a matching primitive operation belonging to the
9832 -- formal ancestor type, so the new subprogram is
9836 and then No (N_Formal)
9837 and then (Ekind (New_E) /= E_Function
9840 (Etype (P_Prim), Etype (New_E)))
9846 Next_Elmt (Prim_Elt);
9849 -- If no match found, then the new subprogram does not override
9850 -- in the generic (nor in the instance).
9852 -- If the type in question is not abstract, and the subprogram
9853 -- is, this will be an error if the new operation is in the
9854 -- private part of the instance. Emit a warning now, which will
9855 -- make the subsequent error message easier to understand.
9857 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9858 and then Is_Abstract_Subprogram (Prev_E)
9859 and then In_Private_Part (Current_Scope)
9861 Error_Msg_Node_2 := F_Typ;
9863 ("private operation& in generic unit does not override "
9864 & "any primitive operation of& (RM 12.3 (18))??",
9874 end Is_Non_Overriding_Operation;
9876 -------------------------------------
9877 -- List_Inherited_Pre_Post_Aspects --
9878 -------------------------------------
9880 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9882 if Opt.List_Inherited_Aspects
9883 and then Is_Subprogram_Or_Generic_Subprogram (E)
9886 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9891 for Index in Subps'Range loop
9892 Items := Contract (Subps (Index));
9894 if Present (Items) then
9895 Prag := Pre_Post_Conditions (Items);
9896 while Present (Prag) loop
9897 Error_Msg_Sloc := Sloc (Prag);
9899 if Class_Present (Prag)
9900 and then not Split_PPC (Prag)
9902 if Pragma_Name (Prag) = Name_Precondition then
9904 ("info: & inherits `Pre''Class` aspect from "
9908 ("info: & inherits `Post''Class` aspect from "
9913 Prag := Next_Pragma (Prag);
9919 end List_Inherited_Pre_Post_Aspects;
9921 ------------------------------
9922 -- Make_Inequality_Operator --
9923 ------------------------------
9925 -- S is the defining identifier of an equality operator. We build a
9926 -- subprogram declaration with the right signature. This operation is
9927 -- intrinsic, because it is always expanded as the negation of the
9928 -- call to the equality function.
9930 procedure Make_Inequality_Operator (S : Entity_Id) is
9931 Loc : constant Source_Ptr := Sloc (S);
9934 Op_Name : Entity_Id;
9936 FF : constant Entity_Id := First_Formal (S);
9937 NF : constant Entity_Id := Next_Formal (FF);
9940 -- Check that equality was properly defined, ignore call if not
9947 A : constant Entity_Id :=
9948 Make_Defining_Identifier (Sloc (FF),
9949 Chars => Chars (FF));
9951 B : constant Entity_Id :=
9952 Make_Defining_Identifier (Sloc (NF),
9953 Chars => Chars (NF));
9956 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9958 Formals := New_List (
9959 Make_Parameter_Specification (Loc,
9960 Defining_Identifier => A,
9962 New_Occurrence_Of (Etype (First_Formal (S)),
9963 Sloc (Etype (First_Formal (S))))),
9965 Make_Parameter_Specification (Loc,
9966 Defining_Identifier => B,
9968 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9969 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9972 Make_Subprogram_Declaration (Loc,
9974 Make_Function_Specification (Loc,
9975 Defining_Unit_Name => Op_Name,
9976 Parameter_Specifications => Formals,
9977 Result_Definition =>
9978 New_Occurrence_Of (Standard_Boolean, Loc)));
9980 -- Insert inequality right after equality if it is explicit or after
9981 -- the derived type when implicit. These entities are created only
9982 -- for visibility purposes, and eventually replaced in the course
9983 -- of expansion, so they do not need to be attached to the tree and
9984 -- seen by the back-end. Keeping them internal also avoids spurious
9985 -- freezing problems. The declaration is inserted in the tree for
9986 -- analysis, and removed afterwards. If the equality operator comes
9987 -- from an explicit declaration, attach the inequality immediately
9988 -- after. Else the equality is inherited from a derived type
9989 -- declaration, so insert inequality after that declaration.
9991 if No (Alias (S)) then
9992 Insert_After (Unit_Declaration_Node (S), Decl);
9993 elsif Is_List_Member (Parent (S)) then
9994 Insert_After (Parent (S), Decl);
9996 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9999 Mark_Rewrite_Insertion (Decl);
10000 Set_Is_Intrinsic_Subprogram (Op_Name);
10003 Set_Has_Completion (Op_Name);
10004 Set_Corresponding_Equality (Op_Name, S);
10005 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
10007 end Make_Inequality_Operator;
10009 ----------------------
10010 -- May_Need_Actuals --
10011 ----------------------
10013 procedure May_Need_Actuals (Fun : Entity_Id) is
10018 F := First_Formal (Fun);
10020 while Present (F) loop
10021 if No (Default_Value (F)) then
10029 Set_Needs_No_Actuals (Fun, B);
10030 end May_Need_Actuals;
10032 ---------------------
10033 -- Mode_Conformant --
10034 ---------------------
10036 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
10039 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
10041 end Mode_Conformant;
10043 ---------------------------
10044 -- New_Overloaded_Entity --
10045 ---------------------------
10047 procedure New_Overloaded_Entity
10049 Derived_Type : Entity_Id := Empty)
10051 Overridden_Subp : Entity_Id := Empty;
10052 -- Set if the current scope has an operation that is type-conformant
10053 -- with S, and becomes hidden by S.
10055 Is_Primitive_Subp : Boolean;
10056 -- Set to True if the new subprogram is primitive
10059 -- Entity that S overrides
10061 procedure Check_For_Primitive_Subprogram
10062 (Is_Primitive : out Boolean;
10063 Is_Overriding : Boolean := False);
10064 -- If the subprogram being analyzed is a primitive operation of the type
10065 -- of a formal or result, set the Has_Primitive_Operations flag on the
10066 -- type, and set Is_Primitive to True (otherwise set to False). Set the
10067 -- corresponding flag on the entity itself for later use.
10069 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10070 -- True if a) E is a subprogram whose first formal is a concurrent type
10071 -- defined in the scope of E that has some entry or subprogram whose
10072 -- profile matches E, or b) E is an internally built dispatching
10073 -- subprogram of a protected type and there is a matching subprogram
10074 -- defined in the enclosing scope of the protected type, or c) E is
10075 -- an entry of a synchronized type and a matching procedure has been
10076 -- previously defined in the enclosing scope of the synchronized type.
10078 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10079 -- Check that E is declared in the private part of the current package,
10080 -- or in the package body, where it may hide a previous declaration.
10081 -- We can't use In_Private_Part by itself because this flag is also
10082 -- set when freezing entities, so we must examine the place of the
10083 -- declaration in the tree, and recognize wrapper packages as well.
10085 function Is_Overriding_Alias
10086 (Old_E : Entity_Id;
10087 New_E : Entity_Id) return Boolean;
10088 -- Check whether new subprogram and old subprogram are both inherited
10089 -- from subprograms that have distinct dispatch table entries. This can
10090 -- occur with derivations from instances with accidental homonyms. The
10091 -- function is conservative given that the converse is only true within
10092 -- instances that contain accidental overloadings.
10094 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10095 -- Report conflict between entities S and E
10097 ------------------------------------
10098 -- Check_For_Primitive_Subprogram --
10099 ------------------------------------
10101 procedure Check_For_Primitive_Subprogram
10102 (Is_Primitive : out Boolean;
10103 Is_Overriding : Boolean := False)
10105 Formal : Entity_Id;
10109 function Visible_Part_Type (T : Entity_Id) return Boolean;
10110 -- Returns true if T is declared in the visible part of the current
10111 -- package scope; otherwise returns false. Assumes that T is declared
10114 procedure Check_Private_Overriding (T : Entity_Id);
10115 -- Checks that if a primitive abstract subprogram of a visible
10116 -- abstract type is declared in a private part, then it must override
10117 -- an abstract subprogram declared in the visible part. Also checks
10118 -- that if a primitive function with a controlling result is declared
10119 -- in a private part, then it must override a function declared in
10120 -- the visible part.
10122 ------------------------------
10123 -- Check_Private_Overriding --
10124 ------------------------------
10126 procedure Check_Private_Overriding (T : Entity_Id) is
10127 function Overrides_Private_Part_Op return Boolean;
10128 -- This detects the special case where the overriding subprogram
10129 -- is overriding a subprogram that was declared in the same
10130 -- private part. That case is illegal by 3.9.3(10).
10132 function Overrides_Visible_Function
10133 (Partial_View : Entity_Id) return Boolean;
10134 -- True if S overrides a function in the visible part. The
10135 -- overridden function could be explicitly or implicitly declared.
10137 -------------------------------
10138 -- Overrides_Private_Part_Op --
10139 -------------------------------
10141 function Overrides_Private_Part_Op return Boolean is
10142 Over_Decl : constant Node_Id :=
10143 Unit_Declaration_Node (Overridden_Operation (S));
10144 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10147 pragma Assert (Is_Overriding);
10149 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10151 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10153 return In_Same_List (Over_Decl, Subp_Decl);
10154 end Overrides_Private_Part_Op;
10156 --------------------------------
10157 -- Overrides_Visible_Function --
10158 --------------------------------
10160 function Overrides_Visible_Function
10161 (Partial_View : Entity_Id) return Boolean
10164 if not Is_Overriding or else not Has_Homonym (S) then
10168 if not Present (Partial_View) then
10172 -- Search through all the homonyms H of S in the current
10173 -- package spec, and return True if we find one that matches.
10174 -- Note that Parent (H) will be the declaration of the
10175 -- partial view of T for a match.
10178 H : Entity_Id := S;
10182 exit when not Present (H) or else Scope (H) /= Scope (S);
10186 N_Private_Extension_Declaration,
10187 N_Private_Type_Declaration)
10188 and then Defining_Identifier (Parent (H)) = Partial_View
10196 end Overrides_Visible_Function;
10198 -- Start of processing for Check_Private_Overriding
10201 if Is_Package_Or_Generic_Package (Current_Scope)
10202 and then In_Private_Part (Current_Scope)
10203 and then Visible_Part_Type (T)
10204 and then not In_Instance
10206 if Is_Abstract_Type (T)
10207 and then Is_Abstract_Subprogram (S)
10208 and then (not Is_Overriding
10209 or else not Is_Abstract_Subprogram (E)
10210 or else Overrides_Private_Part_Op)
10213 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10216 elsif Ekind (S) = E_Function then
10218 Partial_View : constant Entity_Id :=
10219 Incomplete_Or_Partial_View (T);
10222 if not Overrides_Visible_Function (Partial_View) then
10224 -- Here, S is "function ... return T;" declared in
10225 -- the private part, not overriding some visible
10226 -- operation. That's illegal in the tagged case
10227 -- (but not if the private type is untagged).
10229 if ((Present (Partial_View)
10230 and then Is_Tagged_Type (Partial_View))
10231 or else (not Present (Partial_View)
10232 and then Is_Tagged_Type (T)))
10233 and then T = Base_Type (Etype (S))
10236 ("private function with tagged result must"
10237 & " override visible-part function", S);
10239 ("\move subprogram to the visible part"
10240 & " (RM 3.9.3(10))", S);
10242 -- AI05-0073: extend this test to the case of a
10243 -- function with a controlling access result.
10245 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10246 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10248 not Is_Class_Wide_Type
10249 (Designated_Type (Etype (S)))
10250 and then Ada_Version >= Ada_2012
10253 ("private function with controlling access "
10254 & "result must override visible-part function",
10257 ("\move subprogram to the visible part"
10258 & " (RM 3.9.3(10))", S);
10264 end Check_Private_Overriding;
10266 -----------------------
10267 -- Visible_Part_Type --
10268 -----------------------
10270 function Visible_Part_Type (T : Entity_Id) return Boolean is
10271 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10274 -- If the entity is a private type, then it must be declared in a
10277 if Ekind (T) in Private_Kind then
10280 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10283 elsif Is_List_Member (Declaration_Node (T))
10284 and then List_Containing (Declaration_Node (T)) =
10285 Visible_Declarations (Specification (P))
10292 end Visible_Part_Type;
10294 -- Start of processing for Check_For_Primitive_Subprogram
10297 Is_Primitive := False;
10299 if not Comes_From_Source (S) then
10302 -- If subprogram is at library level, it is not primitive operation
10304 elsif Current_Scope = Standard_Standard then
10307 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10308 and then not In_Package_Body (Current_Scope))
10309 or else Is_Overriding
10311 -- For function, check return type
10313 if Ekind (S) = E_Function then
10314 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10315 F_Typ := Designated_Type (Etype (S));
10317 F_Typ := Etype (S);
10320 B_Typ := Base_Type (F_Typ);
10322 if Scope (B_Typ) = Current_Scope
10323 and then not Is_Class_Wide_Type (B_Typ)
10324 and then not Is_Generic_Type (B_Typ)
10326 Is_Primitive := True;
10327 Set_Has_Primitive_Operations (B_Typ);
10328 Set_Is_Primitive (S);
10329 Check_Private_Overriding (B_Typ);
10331 -- The Ghost policy in effect at the point of declaration
10332 -- or a tagged type and a primitive operation must match
10333 -- (SPARK RM 6.9(16)).
10335 Check_Ghost_Primitive (S, B_Typ);
10339 -- For all subprograms, check formals
10341 Formal := First_Formal (S);
10342 while Present (Formal) loop
10343 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10344 F_Typ := Designated_Type (Etype (Formal));
10346 F_Typ := Etype (Formal);
10349 B_Typ := Base_Type (F_Typ);
10351 if Ekind (B_Typ) = E_Access_Subtype then
10352 B_Typ := Base_Type (B_Typ);
10355 if Scope (B_Typ) = Current_Scope
10356 and then not Is_Class_Wide_Type (B_Typ)
10357 and then not Is_Generic_Type (B_Typ)
10359 Is_Primitive := True;
10360 Set_Is_Primitive (S);
10361 Set_Has_Primitive_Operations (B_Typ);
10362 Check_Private_Overriding (B_Typ);
10364 -- The Ghost policy in effect at the point of declaration
10365 -- of a tagged type and a primitive operation must match
10366 -- (SPARK RM 6.9(16)).
10368 Check_Ghost_Primitive (S, B_Typ);
10371 Next_Formal (Formal);
10374 -- Special case: An equality function can be redefined for a type
10375 -- occurring in a declarative part, and won't otherwise be treated as
10376 -- a primitive because it doesn't occur in a package spec and doesn't
10377 -- override an inherited subprogram. It's important that we mark it
10378 -- primitive so it can be returned by Collect_Primitive_Operations
10379 -- and be used in composing the equality operation of later types
10380 -- that have a component of the type.
10382 elsif Chars (S) = Name_Op_Eq
10383 and then Etype (S) = Standard_Boolean
10385 B_Typ := Base_Type (Etype (First_Formal (S)));
10387 if Scope (B_Typ) = Current_Scope
10389 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10390 and then not Is_Limited_Type (B_Typ)
10392 Is_Primitive := True;
10393 Set_Is_Primitive (S);
10394 Set_Has_Primitive_Operations (B_Typ);
10395 Check_Private_Overriding (B_Typ);
10397 -- The Ghost policy in effect at the point of declaration of a
10398 -- tagged type and a primitive operation must match
10399 -- (SPARK RM 6.9(16)).
10401 Check_Ghost_Primitive (S, B_Typ);
10404 end Check_For_Primitive_Subprogram;
10406 --------------------------------------
10407 -- Has_Matching_Entry_Or_Subprogram --
10408 --------------------------------------
10410 function Has_Matching_Entry_Or_Subprogram
10411 (E : Entity_Id) return Boolean
10413 function Check_Conforming_Parameters
10414 (E1_Param : Node_Id;
10415 E2_Param : Node_Id) return Boolean;
10416 -- Starting from the given parameters, check that all the parameters
10417 -- of two entries or subprograms are subtype conformant. Used to skip
10418 -- the check on the controlling argument.
10420 function Matching_Entry_Or_Subprogram
10421 (Conc_Typ : Entity_Id;
10422 Subp : Entity_Id) return Entity_Id;
10423 -- Return the first entry or subprogram of the given concurrent type
10424 -- whose name matches the name of Subp and has a profile conformant
10425 -- with Subp; return Empty if not found.
10427 function Matching_Dispatching_Subprogram
10428 (Conc_Typ : Entity_Id;
10429 Ent : Entity_Id) return Entity_Id;
10430 -- Return the first dispatching primitive of Conc_Type defined in the
10431 -- enclosing scope of Conc_Type (i.e. before the full definition of
10432 -- this concurrent type) whose name matches the entry Ent and has a
10433 -- profile conformant with the profile of the corresponding (not yet
10434 -- built) dispatching primitive of Ent; return Empty if not found.
10436 function Matching_Original_Protected_Subprogram
10437 (Prot_Typ : Entity_Id;
10438 Subp : Entity_Id) return Entity_Id;
10439 -- Return the first subprogram defined in the enclosing scope of
10440 -- Prot_Typ (before the full definition of this protected type)
10441 -- whose name matches the original name of Subp and has a profile
10442 -- conformant with the profile of Subp; return Empty if not found.
10444 ---------------------------------
10445 -- Check_Conforming_Parameters --
10446 ---------------------------------
10448 function Check_Conforming_Parameters
10449 (E1_Param : Node_Id;
10450 E2_Param : Node_Id) return Boolean
10452 Param_E1 : Node_Id := E1_Param;
10453 Param_E2 : Node_Id := E2_Param;
10456 while Present (Param_E1) and then Present (Param_E2) loop
10457 if Ekind (Defining_Identifier (Param_E1)) /=
10458 Ekind (Defining_Identifier (Param_E2))
10461 (Find_Parameter_Type (Param_E1),
10462 Find_Parameter_Type (Param_E2),
10463 Subtype_Conformant)
10472 -- The candidate is not valid if one of the two lists contains
10473 -- more parameters than the other
10475 return No (Param_E1) and then No (Param_E2);
10476 end Check_Conforming_Parameters;
10478 ----------------------------------
10479 -- Matching_Entry_Or_Subprogram --
10480 ----------------------------------
10482 function Matching_Entry_Or_Subprogram
10483 (Conc_Typ : Entity_Id;
10484 Subp : Entity_Id) return Entity_Id
10489 E := First_Entity (Conc_Typ);
10490 while Present (E) loop
10491 if Chars (Subp) = Chars (E)
10492 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10494 Check_Conforming_Parameters
10495 (First (Parameter_Specifications (Parent (E))),
10496 Next (First (Parameter_Specifications (Parent (Subp)))))
10505 end Matching_Entry_Or_Subprogram;
10507 -------------------------------------
10508 -- Matching_Dispatching_Subprogram --
10509 -------------------------------------
10511 function Matching_Dispatching_Subprogram
10512 (Conc_Typ : Entity_Id;
10513 Ent : Entity_Id) return Entity_Id
10518 -- Search for entities in the enclosing scope of this synchonized
10521 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10522 Push_Scope (Scope (Conc_Typ));
10523 E := Current_Entity_In_Scope (Ent);
10526 while Present (E) loop
10527 if Scope (E) = Scope (Conc_Typ)
10528 and then Comes_From_Source (E)
10529 and then Ekind (E) = E_Procedure
10530 and then Present (First_Entity (E))
10531 and then Is_Controlling_Formal (First_Entity (E))
10532 and then Etype (First_Entity (E)) = Conc_Typ
10534 Check_Conforming_Parameters
10535 (First (Parameter_Specifications (Parent (Ent))),
10536 Next (First (Parameter_Specifications (Parent (E)))))
10545 end Matching_Dispatching_Subprogram;
10547 --------------------------------------------
10548 -- Matching_Original_Protected_Subprogram --
10549 --------------------------------------------
10551 function Matching_Original_Protected_Subprogram
10552 (Prot_Typ : Entity_Id;
10553 Subp : Entity_Id) return Entity_Id
10555 ICF : constant Boolean :=
10556 Is_Controlling_Formal (First_Entity (Subp));
10560 -- Temporarily decorate the first parameter of Subp as controlling
10561 -- formal, required to invoke Subtype_Conformant.
10563 Set_Is_Controlling_Formal (First_Entity (Subp));
10566 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10568 while Present (E) loop
10569 if Scope (E) = Scope (Prot_Typ)
10570 and then Comes_From_Source (E)
10571 and then Ekind (Subp) = Ekind (E)
10572 and then Present (First_Entity (E))
10573 and then Is_Controlling_Formal (First_Entity (E))
10574 and then Etype (First_Entity (E)) = Prot_Typ
10575 and then Subtype_Conformant (Subp, E,
10576 Skip_Controlling_Formals => True)
10578 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10585 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10588 end Matching_Original_Protected_Subprogram;
10590 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10593 -- Case 1: E is a subprogram whose first formal is a concurrent type
10594 -- defined in the scope of E that has an entry or subprogram whose
10595 -- profile matches E.
10597 if Comes_From_Source (E)
10598 and then Is_Subprogram (E)
10599 and then Present (First_Entity (E))
10600 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10603 Scope (Corresponding_Concurrent_Type
10604 (Etype (First_Entity (E))))
10607 (Matching_Entry_Or_Subprogram
10608 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10611 Report_Conflict (E,
10612 Matching_Entry_Or_Subprogram
10613 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10618 -- Case 2: E is an internally built dispatching subprogram of a
10619 -- protected type and there is a subprogram defined in the enclosing
10620 -- scope of the protected type that has the original name of E and
10621 -- its profile is conformant with the profile of E. We check the
10622 -- name of the original protected subprogram associated with E since
10623 -- the expander builds dispatching primitives of protected functions
10624 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10626 elsif not Comes_From_Source (E)
10627 and then Is_Subprogram (E)
10628 and then Present (First_Entity (E))
10629 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10630 and then Present (Original_Protected_Subprogram (E))
10633 (Matching_Original_Protected_Subprogram
10634 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10637 Report_Conflict (E,
10638 Matching_Original_Protected_Subprogram
10639 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10643 -- Case 3: E is an entry of a synchronized type and a matching
10644 -- procedure has been previously defined in the enclosing scope
10645 -- of the synchronized type.
10647 elsif Comes_From_Source (E)
10648 and then Ekind (E) = E_Entry
10650 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10652 Report_Conflict (E,
10653 Matching_Dispatching_Subprogram (Current_Scope, E));
10658 end Has_Matching_Entry_Or_Subprogram;
10660 ----------------------------
10661 -- Is_Private_Declaration --
10662 ----------------------------
10664 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10665 Decl : constant Node_Id := Unit_Declaration_Node (E);
10666 Priv_Decls : List_Id;
10669 if Is_Package_Or_Generic_Package (Current_Scope)
10670 and then In_Private_Part (Current_Scope)
10673 Private_Declarations (Package_Specification (Current_Scope));
10675 return In_Package_Body (Current_Scope)
10677 (Is_List_Member (Decl)
10678 and then List_Containing (Decl) = Priv_Decls)
10679 or else (Nkind (Parent (Decl)) = N_Package_Specification
10681 Is_Compilation_Unit
10682 (Defining_Entity (Parent (Decl)))
10683 and then List_Containing (Parent (Parent (Decl))) =
10688 end Is_Private_Declaration;
10690 --------------------------
10691 -- Is_Overriding_Alias --
10692 --------------------------
10694 function Is_Overriding_Alias
10695 (Old_E : Entity_Id;
10696 New_E : Entity_Id) return Boolean
10698 AO : constant Entity_Id := Alias (Old_E);
10699 AN : constant Entity_Id := Alias (New_E);
10702 return Scope (AO) /= Scope (AN)
10703 or else No (DTC_Entity (AO))
10704 or else No (DTC_Entity (AN))
10705 or else DT_Position (AO) = DT_Position (AN);
10706 end Is_Overriding_Alias;
10708 ---------------------
10709 -- Report_Conflict --
10710 ---------------------
10712 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10714 Error_Msg_Sloc := Sloc (E);
10716 -- Generate message, with useful additional warning if in generic
10718 if Is_Generic_Unit (E) then
10719 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10720 Error_Msg_N ("\& conflicts with declaration#", S);
10722 Error_Msg_N ("& conflicts with declaration#", S);
10724 end Report_Conflict;
10726 -- Start of processing for New_Overloaded_Entity
10729 -- We need to look for an entity that S may override. This must be a
10730 -- homonym in the current scope, so we look for the first homonym of
10731 -- S in the current scope as the starting point for the search.
10733 E := Current_Entity_In_Scope (S);
10735 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10736 -- They are directly added to the list of primitive operations of
10737 -- Derived_Type, unless this is a rederivation in the private part
10738 -- of an operation that was already derived in the visible part of
10739 -- the current package.
10741 if Ada_Version >= Ada_2005
10742 and then Present (Derived_Type)
10743 and then Present (Alias (S))
10744 and then Is_Dispatching_Operation (Alias (S))
10745 and then Present (Find_Dispatching_Type (Alias (S)))
10746 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10748 -- For private types, when the full-view is processed we propagate to
10749 -- the full view the non-overridden entities whose attribute "alias"
10750 -- references an interface primitive. These entities were added by
10751 -- Derive_Subprograms to ensure that interface primitives are
10754 -- Inside_Freeze_Actions is non zero when S corresponds with an
10755 -- internal entity that links an interface primitive with its
10756 -- covering primitive through attribute Interface_Alias (see
10757 -- Add_Internal_Interface_Entities).
10759 if Inside_Freezing_Actions = 0
10760 and then Is_Package_Or_Generic_Package (Current_Scope)
10761 and then In_Private_Part (Current_Scope)
10762 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10763 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10764 and then Full_View (Defining_Identifier (Parent (E)))
10765 = Defining_Identifier (Parent (S))
10766 and then Alias (E) = Alias (S)
10768 Check_Operation_From_Private_View (S, E);
10769 Set_Is_Dispatching_Operation (S);
10774 Enter_Overloaded_Entity (S);
10775 Check_Dispatching_Operation (S, Empty);
10776 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10782 -- For synchronized types check conflicts of this entity with previously
10783 -- defined entities.
10785 if Ada_Version >= Ada_2005
10786 and then Has_Matching_Entry_Or_Subprogram (S)
10791 -- If there is no homonym then this is definitely not overriding
10794 Enter_Overloaded_Entity (S);
10795 Check_Dispatching_Operation (S, Empty);
10796 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10798 -- If subprogram has an explicit declaration, check whether it has an
10799 -- overriding indicator.
10801 if Comes_From_Source (S) then
10802 Check_Synchronized_Overriding (S, Overridden_Subp);
10804 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10805 -- it may have overridden some hidden inherited primitive. Update
10806 -- Overridden_Subp to avoid spurious errors when checking the
10807 -- overriding indicator.
10809 if Ada_Version >= Ada_2012
10810 and then No (Overridden_Subp)
10811 and then Is_Dispatching_Operation (S)
10812 and then Present (Overridden_Operation (S))
10814 Overridden_Subp := Overridden_Operation (S);
10817 Check_Overriding_Indicator
10818 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10820 -- The Ghost policy in effect at the point of declaration of a
10821 -- parent subprogram and an overriding subprogram must match
10822 -- (SPARK RM 6.9(17)).
10824 Check_Ghost_Overriding (S, Overridden_Subp);
10827 -- If there is a homonym that is not overloadable, then we have an
10828 -- error, except for the special cases checked explicitly below.
10830 elsif not Is_Overloadable (E) then
10832 -- Check for spurious conflict produced by a subprogram that has the
10833 -- same name as that of the enclosing generic package. The conflict
10834 -- occurs within an instance, between the subprogram and the renaming
10835 -- declaration for the package. After the subprogram, the package
10836 -- renaming declaration becomes hidden.
10838 if Ekind (E) = E_Package
10839 and then Present (Renamed_Object (E))
10840 and then Renamed_Object (E) = Current_Scope
10841 and then Nkind (Parent (Renamed_Object (E))) =
10842 N_Package_Specification
10843 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10846 Set_Is_Immediately_Visible (E, False);
10847 Enter_Overloaded_Entity (S);
10848 Set_Homonym (S, Homonym (E));
10849 Check_Dispatching_Operation (S, Empty);
10850 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10852 -- If the subprogram is implicit it is hidden by the previous
10853 -- declaration. However if it is dispatching, it must appear in the
10854 -- dispatch table anyway, because it can be dispatched to even if it
10855 -- cannot be called directly.
10857 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10858 Set_Scope (S, Current_Scope);
10860 if Is_Dispatching_Operation (Alias (S)) then
10861 Check_Dispatching_Operation (S, Empty);
10867 Report_Conflict (S, E);
10871 -- E exists and is overloadable
10874 Check_Synchronized_Overriding (S, Overridden_Subp);
10876 -- Loop through E and its homonyms to determine if any of them is
10877 -- the candidate for overriding by S.
10879 while Present (E) loop
10881 -- Definitely not interesting if not in the current scope
10883 if Scope (E) /= Current_Scope then
10886 -- A function can overload the name of an abstract state. The
10887 -- state can be viewed as a function with a profile that cannot
10888 -- be matched by anything.
10890 elsif Ekind (S) = E_Function
10891 and then Ekind (E) = E_Abstract_State
10893 Enter_Overloaded_Entity (S);
10896 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10897 -- procedures locate the internally generated spec. We enforce
10898 -- mode conformance since a tagged type may inherit from
10899 -- interfaces several null primitives which differ only in
10900 -- the mode of the formals.
10902 elsif not Comes_From_Source (S)
10903 and then Is_Null_Procedure (S)
10904 and then not Mode_Conformant (E, S)
10908 -- Check if we have type conformance
10910 elsif Type_Conformant (E, S) then
10912 -- If the old and new entities have the same profile and one
10913 -- is not the body of the other, then this is an error, unless
10914 -- one of them is implicitly declared.
10916 -- There are some cases when both can be implicit, for example
10917 -- when both a literal and a function that overrides it are
10918 -- inherited in a derivation, or when an inherited operation
10919 -- of a tagged full type overrides the inherited operation of
10920 -- a private extension. Ada 83 had a special rule for the
10921 -- literal case. In Ada 95, the later implicit operation hides
10922 -- the former, and the literal is always the former. In the
10923 -- odd case where both are derived operations declared at the
10924 -- same point, both operations should be declared, and in that
10925 -- case we bypass the following test and proceed to the next
10926 -- part. This can only occur for certain obscure cases in
10927 -- instances, when an operation on a type derived from a formal
10928 -- private type does not override a homograph inherited from
10929 -- the actual. In subsequent derivations of such a type, the
10930 -- DT positions of these operations remain distinct, if they
10933 if Present (Alias (S))
10934 and then (No (Alias (E))
10935 or else Comes_From_Source (E)
10936 or else Is_Abstract_Subprogram (S)
10938 (Is_Dispatching_Operation (E)
10939 and then Is_Overriding_Alias (E, S)))
10940 and then Ekind (E) /= E_Enumeration_Literal
10942 -- When an derived operation is overloaded it may be due to
10943 -- the fact that the full view of a private extension
10944 -- re-inherits. It has to be dealt with.
10946 if Is_Package_Or_Generic_Package (Current_Scope)
10947 and then In_Private_Part (Current_Scope)
10949 Check_Operation_From_Private_View (S, E);
10952 -- In any case the implicit operation remains hidden by the
10953 -- existing declaration, which is overriding. Indicate that
10954 -- E overrides the operation from which S is inherited.
10956 if Present (Alias (S)) then
10957 Set_Overridden_Operation (E, Alias (S));
10958 Inherit_Subprogram_Contract (E, Alias (S));
10961 Set_Overridden_Operation (E, S);
10962 Inherit_Subprogram_Contract (E, S);
10965 if Comes_From_Source (E) then
10966 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10968 -- The Ghost policy in effect at the point of declaration
10969 -- of a parent subprogram and an overriding subprogram
10970 -- must match (SPARK RM 6.9(17)).
10972 Check_Ghost_Overriding (E, S);
10977 -- Within an instance, the renaming declarations for actual
10978 -- subprograms may become ambiguous, but they do not hide each
10981 elsif Ekind (E) /= E_Entry
10982 and then not Comes_From_Source (E)
10983 and then not Is_Generic_Instance (E)
10984 and then (Present (Alias (E))
10985 or else Is_Intrinsic_Subprogram (E))
10986 and then (not In_Instance
10987 or else No (Parent (E))
10988 or else Nkind (Unit_Declaration_Node (E)) /=
10989 N_Subprogram_Renaming_Declaration)
10991 -- A subprogram child unit is not allowed to override an
10992 -- inherited subprogram (10.1.1(20)).
10994 if Is_Child_Unit (S) then
10996 ("child unit overrides inherited subprogram in parent",
11001 if Is_Non_Overriding_Operation (E, S) then
11002 Enter_Overloaded_Entity (S);
11004 if No (Derived_Type)
11005 or else Is_Tagged_Type (Derived_Type)
11007 Check_Dispatching_Operation (S, Empty);
11013 -- E is a derived operation or an internal operator which
11014 -- is being overridden. Remove E from further visibility.
11015 -- Furthermore, if E is a dispatching operation, it must be
11016 -- replaced in the list of primitive operations of its type
11017 -- (see Override_Dispatching_Operation).
11019 Overridden_Subp := E;
11021 -- It is possible for E to be in the current scope and
11022 -- yet not in the entity chain. This can only occur in a
11023 -- generic context where E is an implicit concatenation
11024 -- in the formal part, because in a generic body the
11025 -- entity chain starts with the formals.
11027 -- In GNATprove mode, a wrapper for an operation with
11028 -- axiomatization may be a homonym of another declaration
11029 -- for an actual subprogram (needs refinement ???).
11031 if No (Prev_Entity (E)) then
11033 and then GNATprove_Mode
11035 Nkind (Original_Node (Unit_Declaration_Node (S))) =
11036 N_Subprogram_Renaming_Declaration
11040 pragma Assert (Chars (E) = Name_Op_Concat);
11045 -- E must be removed both from the entity_list of the
11046 -- current scope, and from the visibility chain.
11048 if Debug_Flag_E then
11049 Write_Str ("Override implicit operation ");
11050 Write_Int (Int (E));
11054 -- If E is a predefined concatenation, it stands for four
11055 -- different operations. As a result, a single explicit
11056 -- declaration does not hide it. In a possible ambiguous
11057 -- situation, Disambiguate chooses the user-defined op,
11058 -- so it is correct to retain the previous internal one.
11060 if Chars (E) /= Name_Op_Concat
11061 or else Ekind (E) /= E_Operator
11063 -- For nondispatching derived operations that are
11064 -- overridden by a subprogram declared in the private
11065 -- part of a package, we retain the derived subprogram
11066 -- but mark it as not immediately visible. If the
11067 -- derived operation was declared in the visible part
11068 -- then this ensures that it will still be visible
11069 -- outside the package with the proper signature
11070 -- (calls from outside must also be directed to this
11071 -- version rather than the overriding one, unlike the
11072 -- dispatching case). Calls from inside the package
11073 -- will still resolve to the overriding subprogram
11074 -- since the derived one is marked as not visible
11075 -- within the package.
11077 -- If the private operation is dispatching, we achieve
11078 -- the overriding by keeping the implicit operation
11079 -- but setting its alias to be the overriding one. In
11080 -- this fashion the proper body is executed in all
11081 -- cases, but the original signature is used outside
11084 -- If the overriding is not in the private part, we
11085 -- remove the implicit operation altogether.
11087 if Is_Private_Declaration (S) then
11088 if not Is_Dispatching_Operation (E) then
11089 Set_Is_Immediately_Visible (E, False);
11091 -- Work done in Override_Dispatching_Operation, so
11092 -- nothing else needs to be done here.
11098 Remove_Entity_And_Homonym (E);
11102 Enter_Overloaded_Entity (S);
11104 -- For entities generated by Derive_Subprograms the
11105 -- overridden operation is the inherited primitive
11106 -- (which is available through the attribute alias).
11108 if not (Comes_From_Source (E))
11109 and then Is_Dispatching_Operation (E)
11110 and then Find_Dispatching_Type (E) =
11111 Find_Dispatching_Type (S)
11112 and then Present (Alias (E))
11113 and then Comes_From_Source (Alias (E))
11115 Set_Overridden_Operation (S, Alias (E));
11116 Inherit_Subprogram_Contract (S, Alias (E));
11118 -- Normal case of setting entity as overridden
11120 -- Note: Static_Initialization and Overridden_Operation
11121 -- attributes use the same field in subprogram entities.
11122 -- Static_Initialization is only defined for internal
11123 -- initialization procedures, where Overridden_Operation
11124 -- is irrelevant. Therefore the setting of this attribute
11125 -- must check whether the target is an init_proc.
11127 elsif not Is_Init_Proc (S) then
11128 Set_Overridden_Operation (S, E);
11129 Inherit_Subprogram_Contract (S, E);
11132 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11134 -- The Ghost policy in effect at the point of declaration
11135 -- of a parent subprogram and an overriding subprogram
11136 -- must match (SPARK RM 6.9(17)).
11138 Check_Ghost_Overriding (S, E);
11140 -- If S is a user-defined subprogram or a null procedure
11141 -- expanded to override an inherited null procedure, or a
11142 -- predefined dispatching primitive then indicate that E
11143 -- overrides the operation from which S is inherited.
11145 if Comes_From_Source (S)
11147 (Present (Parent (S))
11148 and then Nkind (Parent (S)) = N_Procedure_Specification
11149 and then Null_Present (Parent (S)))
11151 (Present (Alias (E))
11153 Is_Predefined_Dispatching_Operation (Alias (E)))
11155 if Present (Alias (E)) then
11156 Set_Overridden_Operation (S, Alias (E));
11157 Inherit_Subprogram_Contract (S, Alias (E));
11161 if Is_Dispatching_Operation (E) then
11163 -- An overriding dispatching subprogram inherits the
11164 -- convention of the overridden subprogram (AI-117).
11166 Set_Convention (S, Convention (E));
11167 Check_Dispatching_Operation (S, E);
11170 Check_Dispatching_Operation (S, Empty);
11173 Check_For_Primitive_Subprogram
11174 (Is_Primitive_Subp, Is_Overriding => True);
11175 goto Check_Inequality;
11177 -- Apparent redeclarations in instances can occur when two
11178 -- formal types get the same actual type. The subprograms in
11179 -- in the instance are legal, even if not callable from the
11180 -- outside. Calls from within are disambiguated elsewhere.
11181 -- For dispatching operations in the visible part, the usual
11182 -- rules apply, and operations with the same profile are not
11183 -- legal (B830001).
11185 elsif (In_Instance_Visible_Part
11186 and then not Is_Dispatching_Operation (E))
11187 or else In_Instance_Not_Visible
11191 -- Here we have a real error (identical profile)
11194 Error_Msg_Sloc := Sloc (E);
11196 -- Avoid cascaded errors if the entity appears in
11197 -- subsequent calls.
11199 Set_Scope (S, Current_Scope);
11201 -- Generate error, with extra useful warning for the case
11202 -- of a generic instance with no completion.
11204 if Is_Generic_Instance (S)
11205 and then not Has_Completion (E)
11208 ("instantiation cannot provide body for&", S);
11209 Error_Msg_N ("\& conflicts with declaration#", S);
11211 Error_Msg_N ("& conflicts with declaration#", S);
11218 -- If one subprogram has an access parameter and the other
11219 -- a parameter of an access type, calls to either might be
11220 -- ambiguous. Verify that parameters match except for the
11221 -- access parameter.
11223 if May_Hide_Profile then
11229 F1 := First_Formal (S);
11230 F2 := First_Formal (E);
11231 while Present (F1) and then Present (F2) loop
11232 if Is_Access_Type (Etype (F1)) then
11233 if not Is_Access_Type (Etype (F2))
11234 or else not Conforming_Types
11235 (Designated_Type (Etype (F1)),
11236 Designated_Type (Etype (F2)),
11239 May_Hide_Profile := False;
11243 not Conforming_Types
11244 (Etype (F1), Etype (F2), Type_Conformant)
11246 May_Hide_Profile := False;
11253 if May_Hide_Profile
11257 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11266 -- On exit, we know that S is a new entity
11268 Enter_Overloaded_Entity (S);
11269 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11270 Check_Overriding_Indicator
11271 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11273 -- The Ghost policy in effect at the point of declaration of a parent
11274 -- subprogram and an overriding subprogram must match
11275 -- (SPARK RM 6.9(17)).
11277 Check_Ghost_Overriding (S, Overridden_Subp);
11279 -- Overloading is not allowed in SPARK, except for operators
11281 if Nkind (S) /= N_Defining_Operator_Symbol then
11282 Error_Msg_Sloc := Sloc (Homonym (S));
11283 Check_SPARK_05_Restriction
11284 ("overloading not allowed with entity#", S);
11287 -- If S is a derived operation for an untagged type then by
11288 -- definition it's not a dispatching operation (even if the parent
11289 -- operation was dispatching), so Check_Dispatching_Operation is not
11290 -- called in that case.
11292 if No (Derived_Type)
11293 or else Is_Tagged_Type (Derived_Type)
11295 Check_Dispatching_Operation (S, Empty);
11299 -- If this is a user-defined equality operator that is not a derived
11300 -- subprogram, create the corresponding inequality. If the operation is
11301 -- dispatching, the expansion is done elsewhere, and we do not create
11302 -- an explicit inequality operation.
11304 <<Check_Inequality>>
11305 if Chars (S) = Name_Op_Eq
11306 and then Etype (S) = Standard_Boolean
11307 and then Present (Parent (S))
11308 and then not Is_Dispatching_Operation (S)
11310 Make_Inequality_Operator (S);
11311 Check_Untagged_Equality (S);
11313 end New_Overloaded_Entity;
11315 ---------------------
11316 -- Process_Formals --
11317 ---------------------
11319 procedure Process_Formals
11321 Related_Nod : Node_Id)
11323 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11324 -- Determine whether an access type designates a type coming from a
11327 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11328 -- Check whether the default has a class-wide type. After analysis the
11329 -- default has the type of the formal, so we must also check explicitly
11330 -- for an access attribute.
11332 ----------------------------------
11333 -- Designates_From_Limited_With --
11334 ----------------------------------
11336 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11337 Desig : Entity_Id := Typ;
11340 if Is_Access_Type (Desig) then
11341 Desig := Directly_Designated_Type (Desig);
11344 if Is_Class_Wide_Type (Desig) then
11345 Desig := Root_Type (Desig);
11349 Ekind (Desig) = E_Incomplete_Type
11350 and then From_Limited_With (Desig);
11351 end Designates_From_Limited_With;
11353 ---------------------------
11354 -- Is_Class_Wide_Default --
11355 ---------------------------
11357 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11359 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11360 or else (Nkind (D) = N_Attribute_Reference
11361 and then Attribute_Name (D) = Name_Access
11362 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11363 end Is_Class_Wide_Default;
11367 Context : constant Node_Id := Parent (Parent (T));
11369 Formal : Entity_Id;
11370 Formal_Type : Entity_Id;
11371 Param_Spec : Node_Id;
11374 Num_Out_Params : Nat := 0;
11375 First_Out_Param : Entity_Id := Empty;
11376 -- Used for setting Is_Only_Out_Parameter
11378 -- Start of processing for Process_Formals
11381 -- In order to prevent premature use of the formals in the same formal
11382 -- part, the Ekind is left undefined until all default expressions are
11383 -- analyzed. The Ekind is established in a separate loop at the end.
11385 Param_Spec := First (T);
11386 while Present (Param_Spec) loop
11387 Formal := Defining_Identifier (Param_Spec);
11388 Set_Never_Set_In_Source (Formal, True);
11389 Enter_Name (Formal);
11391 -- Case of ordinary parameters
11393 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11394 Find_Type (Parameter_Type (Param_Spec));
11395 Ptype := Parameter_Type (Param_Spec);
11397 if Ptype = Error then
11401 Formal_Type := Entity (Ptype);
11403 if Is_Incomplete_Type (Formal_Type)
11405 (Is_Class_Wide_Type (Formal_Type)
11406 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11408 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11409 -- primitive operations, as long as their completion is
11410 -- in the same declarative part. If in the private part
11411 -- this means that the type cannot be a Taft-amendment type.
11412 -- Check is done on package exit. For access to subprograms,
11413 -- the use is legal for Taft-amendment types.
11415 -- Ada 2012: tagged incomplete types are allowed as generic
11416 -- formal types. They do not introduce dependencies and the
11417 -- corresponding generic subprogram does not have a delayed
11418 -- freeze, because it does not need a freeze node. However,
11419 -- it is still the case that untagged incomplete types cannot
11420 -- be Taft-amendment types and must be completed in private
11421 -- part, so the subprogram must appear in the list of private
11422 -- dependents of the type.
11424 if Is_Tagged_Type (Formal_Type)
11425 or else (Ada_Version >= Ada_2012
11426 and then not From_Limited_With (Formal_Type)
11427 and then not Is_Generic_Type (Formal_Type))
11429 if Ekind (Scope (Current_Scope)) = E_Package
11430 and then not Is_Generic_Type (Formal_Type)
11431 and then not Is_Class_Wide_Type (Formal_Type)
11434 (Parent (T), N_Access_Function_Definition,
11435 N_Access_Procedure_Definition)
11437 Append_Elmt (Current_Scope,
11438 Private_Dependents (Base_Type (Formal_Type)));
11440 -- Freezing is delayed to ensure that Register_Prim
11441 -- will get called for this operation, which is needed
11442 -- in cases where static dispatch tables aren't built.
11443 -- (Note that the same is done for controlling access
11444 -- parameter cases in function Access_Definition.)
11446 if not Is_Thunk (Current_Scope) then
11447 Set_Has_Delayed_Freeze (Current_Scope);
11452 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11453 N_Access_Procedure_Definition)
11455 -- AI05-0151: Tagged incomplete types are allowed in all
11456 -- formal parts. Untagged incomplete types are not allowed
11457 -- in bodies. Limited views of either kind are not allowed
11458 -- if there is no place at which the non-limited view can
11459 -- become available.
11461 -- Incomplete formal untagged types are not allowed in
11462 -- subprogram bodies (but are legal in their declarations).
11463 -- This excludes bodies created for null procedures, which
11464 -- are basic declarations.
11466 if Is_Generic_Type (Formal_Type)
11467 and then not Is_Tagged_Type (Formal_Type)
11468 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11471 ("invalid use of formal incomplete type", Param_Spec);
11473 elsif Ada_Version >= Ada_2012 then
11474 if Is_Tagged_Type (Formal_Type)
11475 and then (not From_Limited_With (Formal_Type)
11476 or else not In_Package_Body)
11480 elsif Nkind_In (Context, N_Accept_Statement,
11481 N_Accept_Alternative,
11483 or else (Nkind (Context) = N_Subprogram_Body
11484 and then Comes_From_Source (Context))
11487 ("invalid use of untagged incomplete type &",
11488 Ptype, Formal_Type);
11493 ("invalid use of incomplete type&",
11494 Param_Spec, Formal_Type);
11496 -- Further checks on the legality of incomplete types
11497 -- in formal parts are delayed until the freeze point
11498 -- of the enclosing subprogram or access to subprogram.
11502 elsif Ekind (Formal_Type) = E_Void then
11504 ("premature use of&",
11505 Parameter_Type (Param_Spec), Formal_Type);
11508 -- Ada 2012 (AI-142): Handle aliased parameters
11510 if Ada_Version >= Ada_2012
11511 and then Aliased_Present (Param_Spec)
11513 Set_Is_Aliased (Formal);
11516 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11517 -- declaration corresponding to the null-excluding type of the
11518 -- formal in the enclosing scope. Finally, replace the parameter
11519 -- type of the formal with the internal subtype.
11521 if Ada_Version >= Ada_2005
11522 and then Null_Exclusion_Present (Param_Spec)
11524 if not Is_Access_Type (Formal_Type) then
11526 ("`NOT NULL` allowed only for an access type", Param_Spec);
11529 if Can_Never_Be_Null (Formal_Type)
11530 and then Comes_From_Source (Related_Nod)
11533 ("`NOT NULL` not allowed (& already excludes null)",
11534 Param_Spec, Formal_Type);
11538 Create_Null_Excluding_Itype
11540 Related_Nod => Related_Nod,
11541 Scope_Id => Scope (Current_Scope));
11543 -- If the designated type of the itype is an itype that is
11544 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11545 -- on the access subtype, to prevent order-of-elaboration
11546 -- issues in the backend.
11549 -- type T is access procedure;
11550 -- procedure Op (O : not null T);
11552 if Is_Itype (Directly_Designated_Type (Formal_Type))
11554 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11556 Set_Has_Delayed_Freeze (Formal_Type);
11561 -- An access formal type
11565 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11567 -- No need to continue if we already notified errors
11569 if not Present (Formal_Type) then
11573 -- Ada 2005 (AI-254)
11576 AD : constant Node_Id :=
11577 Access_To_Subprogram_Definition
11578 (Parameter_Type (Param_Spec));
11580 if Present (AD) and then Protected_Present (AD) then
11582 Replace_Anonymous_Access_To_Protected_Subprogram
11588 Set_Etype (Formal, Formal_Type);
11590 -- Deal with default expression if present
11592 Default := Expression (Param_Spec);
11594 if Present (Default) then
11595 Check_SPARK_05_Restriction
11596 ("default expression is not allowed", Default);
11598 if Out_Present (Param_Spec) then
11600 ("default initialization only allowed for IN parameters",
11604 -- Do the special preanalysis of the expression (see section on
11605 -- "Handling of Default Expressions" in the spec of package Sem).
11607 Preanalyze_Spec_Expression (Default, Formal_Type);
11609 -- An access to constant cannot be the default for
11610 -- an access parameter that is an access to variable.
11612 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11613 and then not Is_Access_Constant (Formal_Type)
11614 and then Is_Access_Type (Etype (Default))
11615 and then Is_Access_Constant (Etype (Default))
11618 ("formal that is access to variable cannot be initialized "
11619 & "with an access-to-constant expression", Default);
11622 -- Check that the designated type of an access parameter's default
11623 -- is not a class-wide type unless the parameter's designated type
11624 -- is also class-wide.
11626 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11627 and then not Designates_From_Limited_With (Formal_Type)
11628 and then Is_Class_Wide_Default (Default)
11629 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11632 ("access to class-wide expression not allowed here", Default);
11635 -- Check incorrect use of dynamically tagged expressions
11637 if Is_Tagged_Type (Formal_Type) then
11638 Check_Dynamically_Tagged_Expression
11640 Typ => Formal_Type,
11641 Related_Nod => Default);
11645 -- Ada 2005 (AI-231): Static checks
11647 if Ada_Version >= Ada_2005
11648 and then Is_Access_Type (Etype (Formal))
11649 and then Can_Never_Be_Null (Etype (Formal))
11651 Null_Exclusion_Static_Checks (Param_Spec);
11654 -- The following checks are relevant only when SPARK_Mode is on as
11655 -- these are not standard Ada legality rules.
11657 if SPARK_Mode = On then
11658 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11660 -- A function cannot have a parameter of mode IN OUT or OUT
11663 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11665 ("function cannot have parameter of mode `OUT` or "
11666 & "`IN OUT`", Formal);
11669 -- A procedure cannot have an effectively volatile formal
11670 -- parameter of mode IN because it behaves as a constant
11671 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11673 elsif Ekind (Scope (Formal)) = E_Procedure
11674 and then Ekind (Formal) = E_In_Parameter
11675 and then Is_Effectively_Volatile (Formal)
11678 ("formal parameter of mode `IN` cannot be volatile", Formal);
11686 -- If this is the formal part of a function specification, analyze the
11687 -- subtype mark in the context where the formals are visible but not
11688 -- yet usable, and may hide outer homographs.
11690 if Nkind (Related_Nod) = N_Function_Specification then
11691 Analyze_Return_Type (Related_Nod);
11694 -- Now set the kind (mode) of each formal
11696 Param_Spec := First (T);
11697 while Present (Param_Spec) loop
11698 Formal := Defining_Identifier (Param_Spec);
11699 Set_Formal_Mode (Formal);
11701 if Ekind (Formal) = E_In_Parameter then
11702 Set_Default_Value (Formal, Expression (Param_Spec));
11704 if Present (Expression (Param_Spec)) then
11705 Default := Expression (Param_Spec);
11707 if Is_Scalar_Type (Etype (Default)) then
11708 if Nkind (Parameter_Type (Param_Spec)) /=
11709 N_Access_Definition
11711 Formal_Type := Entity (Parameter_Type (Param_Spec));
11715 (Related_Nod, Parameter_Type (Param_Spec));
11718 Apply_Scalar_Range_Check (Default, Formal_Type);
11722 elsif Ekind (Formal) = E_Out_Parameter then
11723 Num_Out_Params := Num_Out_Params + 1;
11725 if Num_Out_Params = 1 then
11726 First_Out_Param := Formal;
11729 elsif Ekind (Formal) = E_In_Out_Parameter then
11730 Num_Out_Params := Num_Out_Params + 1;
11733 -- Skip remaining processing if formal type was in error
11735 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11736 goto Next_Parameter;
11739 -- Force call by reference if aliased
11742 Conv : constant Convention_Id := Convention (Etype (Formal));
11744 if Is_Aliased (Formal) then
11745 Set_Mechanism (Formal, By_Reference);
11747 -- Warn if user asked this to be passed by copy
11749 if Conv = Convention_Ada_Pass_By_Copy then
11751 ("cannot pass aliased parameter & by copy??", Formal);
11754 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11756 elsif Conv = Convention_Ada_Pass_By_Copy then
11757 Set_Mechanism (Formal, By_Copy);
11759 elsif Conv = Convention_Ada_Pass_By_Reference then
11760 Set_Mechanism (Formal, By_Reference);
11768 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11769 Set_Is_Only_Out_Parameter (First_Out_Param);
11771 end Process_Formals;
11773 ----------------------------
11774 -- Reference_Body_Formals --
11775 ----------------------------
11777 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11782 if Error_Posted (Spec) then
11786 -- Iterate over both lists. They may be of different lengths if the two
11787 -- specs are not conformant.
11789 Fs := First_Formal (Spec);
11790 Fb := First_Formal (Bod);
11791 while Present (Fs) and then Present (Fb) loop
11792 Generate_Reference (Fs, Fb, 'b');
11794 if Style_Check then
11795 Style.Check_Identifier (Fb, Fs);
11798 Set_Spec_Entity (Fb, Fs);
11799 Set_Referenced (Fs, False);
11803 end Reference_Body_Formals;
11805 -------------------------
11806 -- Set_Actual_Subtypes --
11807 -------------------------
11809 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11811 Formal : Entity_Id;
11813 First_Stmt : Node_Id := Empty;
11814 AS_Needed : Boolean;
11817 -- If this is an empty initialization procedure, no need to create
11818 -- actual subtypes (small optimization).
11820 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11823 -- Within a predicate function we do not want to generate local
11824 -- subtypes that may generate nested predicate functions.
11826 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11830 -- The subtype declarations may freeze the formals. The body generated
11831 -- for an expression function is not a freeze point, so do not emit
11832 -- these declarations (small loss of efficiency in rare cases).
11834 if Nkind (N) = N_Subprogram_Body
11835 and then Was_Expression_Function (N)
11840 Formal := First_Formal (Subp);
11841 while Present (Formal) loop
11842 T := Etype (Formal);
11844 -- We never need an actual subtype for a constrained formal
11846 if Is_Constrained (T) then
11847 AS_Needed := False;
11849 -- If we have unknown discriminants, then we do not need an actual
11850 -- subtype, or more accurately we cannot figure it out. Note that
11851 -- all class-wide types have unknown discriminants.
11853 elsif Has_Unknown_Discriminants (T) then
11854 AS_Needed := False;
11856 -- At this stage we have an unconstrained type that may need an
11857 -- actual subtype. For sure the actual subtype is needed if we have
11858 -- an unconstrained array type. However, in an instance, the type
11859 -- may appear as a subtype of the full view, while the actual is
11860 -- in fact private (in which case no actual subtype is needed) so
11861 -- check the kind of the base type.
11863 elsif Is_Array_Type (Base_Type (T)) then
11866 -- The only other case needing an actual subtype is an unconstrained
11867 -- record type which is an IN parameter (we cannot generate actual
11868 -- subtypes for the OUT or IN OUT case, since an assignment can
11869 -- change the discriminant values. However we exclude the case of
11870 -- initialization procedures, since discriminants are handled very
11871 -- specially in this context, see the section entitled "Handling of
11872 -- Discriminants" in Einfo.
11874 -- We also exclude the case of Discrim_SO_Functions (functions used
11875 -- in front-end layout mode for size/offset values), since in such
11876 -- functions only discriminants are referenced, and not only are such
11877 -- subtypes not needed, but they cannot always be generated, because
11878 -- of order of elaboration issues.
11880 elsif Is_Record_Type (T)
11881 and then Ekind (Formal) = E_In_Parameter
11882 and then Chars (Formal) /= Name_uInit
11883 and then not Is_Unchecked_Union (T)
11884 and then not Is_Discrim_SO_Function (Subp)
11888 -- All other cases do not need an actual subtype
11891 AS_Needed := False;
11894 -- Generate actual subtypes for unconstrained arrays and
11895 -- unconstrained discriminated records.
11898 if Nkind (N) = N_Accept_Statement then
11900 -- If expansion is active, the formal is replaced by a local
11901 -- variable that renames the corresponding entry of the
11902 -- parameter block, and it is this local variable that may
11903 -- require an actual subtype.
11905 if Expander_Active then
11906 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11908 Decl := Build_Actual_Subtype (T, Formal);
11911 if Present (Handled_Statement_Sequence (N)) then
11913 First (Statements (Handled_Statement_Sequence (N)));
11914 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11915 Mark_Rewrite_Insertion (Decl);
11917 -- If the accept statement has no body, there will be no
11918 -- reference to the actuals, so no need to compute actual
11925 Decl := Build_Actual_Subtype (T, Formal);
11926 Prepend (Decl, Declarations (N));
11927 Mark_Rewrite_Insertion (Decl);
11930 -- The declaration uses the bounds of an existing object, and
11931 -- therefore needs no constraint checks.
11933 Analyze (Decl, Suppress => All_Checks);
11934 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11936 -- We need to freeze manually the generated type when it is
11937 -- inserted anywhere else than in a declarative part.
11939 if Present (First_Stmt) then
11940 Insert_List_Before_And_Analyze (First_Stmt,
11941 Freeze_Entity (Defining_Identifier (Decl), N));
11943 -- Ditto if the type has a dynamic predicate, because the
11944 -- generated function will mention the actual subtype. The
11945 -- predicate may come from an explicit aspect of be inherited.
11947 elsif Has_Predicates (T) then
11948 Insert_List_Before_And_Analyze (Decl,
11949 Freeze_Entity (Defining_Identifier (Decl), N));
11952 if Nkind (N) = N_Accept_Statement
11953 and then Expander_Active
11955 Set_Actual_Subtype (Renamed_Object (Formal),
11956 Defining_Identifier (Decl));
11958 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11962 Next_Formal (Formal);
11964 end Set_Actual_Subtypes;
11966 ---------------------
11967 -- Set_Formal_Mode --
11968 ---------------------
11970 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11971 Spec : constant Node_Id := Parent (Formal_Id);
11972 Id : constant Entity_Id := Scope (Formal_Id);
11975 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11976 -- since we ensure that corresponding actuals are always valid at the
11977 -- point of the call.
11979 if Out_Present (Spec) then
11980 if Ekind_In (Id, E_Entry, E_Entry_Family)
11981 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11983 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11986 if Ekind_In (Id, E_Function, E_Generic_Function) then
11988 -- [IN] OUT parameters allowed for functions in Ada 2012
11990 if Ada_Version >= Ada_2012 then
11992 -- Even in Ada 2012 operators can only have IN parameters
11994 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11995 Error_Msg_N ("operators can only have IN parameters", Spec);
11998 if In_Present (Spec) then
11999 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12001 Set_Ekind (Formal_Id, E_Out_Parameter);
12004 -- But not in earlier versions of Ada
12007 Error_Msg_N ("functions can only have IN parameters", Spec);
12008 Set_Ekind (Formal_Id, E_In_Parameter);
12011 elsif In_Present (Spec) then
12012 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12015 Set_Ekind (Formal_Id, E_Out_Parameter);
12016 Set_Never_Set_In_Source (Formal_Id, True);
12017 Set_Is_True_Constant (Formal_Id, False);
12018 Set_Current_Value (Formal_Id, Empty);
12022 Set_Ekind (Formal_Id, E_In_Parameter);
12025 -- Set Is_Known_Non_Null for access parameters since the language
12026 -- guarantees that access parameters are always non-null. We also set
12027 -- Can_Never_Be_Null, since there is no way to change the value.
12029 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
12031 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
12032 -- null; In Ada 2005, only if then null_exclusion is explicit.
12034 if Ada_Version < Ada_2005
12035 or else Can_Never_Be_Null (Etype (Formal_Id))
12037 Set_Is_Known_Non_Null (Formal_Id);
12038 Set_Can_Never_Be_Null (Formal_Id);
12041 -- Ada 2005 (AI-231): Null-exclusion access subtype
12043 elsif Is_Access_Type (Etype (Formal_Id))
12044 and then Can_Never_Be_Null (Etype (Formal_Id))
12046 Set_Is_Known_Non_Null (Formal_Id);
12048 -- We can also set Can_Never_Be_Null (thus preventing some junk
12049 -- access checks) for the case of an IN parameter, which cannot
12050 -- be changed, or for an IN OUT parameter, which can be changed but
12051 -- not to a null value. But for an OUT parameter, the initial value
12052 -- passed in can be null, so we can't set this flag in that case.
12054 if Ekind (Formal_Id) /= E_Out_Parameter then
12055 Set_Can_Never_Be_Null (Formal_Id);
12059 Set_Mechanism (Formal_Id, Default_Mechanism);
12060 Set_Formal_Validity (Formal_Id);
12061 end Set_Formal_Mode;
12063 -------------------------
12064 -- Set_Formal_Validity --
12065 -------------------------
12067 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12069 -- If no validity checking, then we cannot assume anything about the
12070 -- validity of parameters, since we do not know there is any checking
12071 -- of the validity on the call side.
12073 if not Validity_Checks_On then
12076 -- If validity checking for parameters is enabled, this means we are
12077 -- not supposed to make any assumptions about argument values.
12079 elsif Validity_Check_Parameters then
12082 -- If we are checking in parameters, we will assume that the caller is
12083 -- also checking parameters, so we can assume the parameter is valid.
12085 elsif Ekind (Formal_Id) = E_In_Parameter
12086 and then Validity_Check_In_Params
12088 Set_Is_Known_Valid (Formal_Id, True);
12090 -- Similar treatment for IN OUT parameters
12092 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12093 and then Validity_Check_In_Out_Params
12095 Set_Is_Known_Valid (Formal_Id, True);
12097 end Set_Formal_Validity;
12099 ------------------------
12100 -- Subtype_Conformant --
12101 ------------------------
12103 function Subtype_Conformant
12104 (New_Id : Entity_Id;
12105 Old_Id : Entity_Id;
12106 Skip_Controlling_Formals : Boolean := False) return Boolean
12110 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12111 Skip_Controlling_Formals => Skip_Controlling_Formals);
12113 end Subtype_Conformant;
12115 ---------------------
12116 -- Type_Conformant --
12117 ---------------------
12119 function Type_Conformant
12120 (New_Id : Entity_Id;
12121 Old_Id : Entity_Id;
12122 Skip_Controlling_Formals : Boolean := False) return Boolean
12126 May_Hide_Profile := False;
12128 (New_Id, Old_Id, Type_Conformant, False, Result,
12129 Skip_Controlling_Formals => Skip_Controlling_Formals);
12131 end Type_Conformant;
12133 -------------------------------
12134 -- Valid_Operator_Definition --
12135 -------------------------------
12137 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12140 Id : constant Name_Id := Chars (Designator);
12144 F := First_Formal (Designator);
12145 while Present (F) loop
12148 if Present (Default_Value (F)) then
12150 ("default values not allowed for operator parameters",
12153 -- For function instantiations that are operators, we must check
12154 -- separately that the corresponding generic only has in-parameters.
12155 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12156 -- an error could not arise in earlier versions of the language.
12158 elsif Ekind (F) /= E_In_Parameter then
12159 Error_Msg_N ("operators can only have IN parameters", F);
12165 -- Verify that user-defined operators have proper number of arguments
12166 -- First case of operators which can only be unary
12168 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12171 -- Case of operators which can be unary or binary
12173 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12174 N_OK := (N in 1 .. 2);
12176 -- All other operators can only be binary
12184 ("incorrect number of arguments for operator", Designator);
12188 and then Base_Type (Etype (Designator)) = Standard_Boolean
12189 and then not Is_Intrinsic_Subprogram (Designator)
12192 ("explicit definition of inequality not allowed", Designator);
12194 end Valid_Operator_Definition;