1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Disp; use Exp_Disp;
40 with Exp_Tss; use Exp_Tss;
41 with Exp_Util; use Exp_Util;
42 with Freeze; use Freeze;
43 with Ghost; use Ghost;
44 with Inline; use Inline;
45 with Itypes; use Itypes;
46 with Lib.Xref; use Lib.Xref;
47 with Layout; use Layout;
48 with Namet; use Namet;
50 with Nlists; use Nlists;
51 with Nmake; use Nmake;
53 with Output; use Output;
54 with Restrict; use Restrict;
55 with Rident; use Rident;
56 with Rtsfind; use Rtsfind;
58 with Sem_Aux; use Sem_Aux;
59 with Sem_Cat; use Sem_Cat;
60 with Sem_Ch3; use Sem_Ch3;
61 with Sem_Ch4; use Sem_Ch4;
62 with Sem_Ch5; use Sem_Ch5;
63 with Sem_Ch8; use Sem_Ch8;
64 with Sem_Ch9; use Sem_Ch9;
65 with Sem_Ch10; use Sem_Ch10;
66 with Sem_Ch12; use Sem_Ch12;
67 with Sem_Ch13; use Sem_Ch13;
68 with Sem_Dim; use Sem_Dim;
69 with Sem_Disp; use Sem_Disp;
70 with Sem_Dist; use Sem_Dist;
71 with Sem_Elim; use Sem_Elim;
72 with Sem_Eval; use Sem_Eval;
73 with Sem_Mech; use Sem_Mech;
74 with Sem_Prag; use Sem_Prag;
75 with Sem_Res; use Sem_Res;
76 with Sem_Util; use Sem_Util;
77 with Sem_Type; use Sem_Type;
78 with Sem_Warn; use Sem_Warn;
79 with Sinput; use Sinput;
80 with Stand; use Stand;
81 with Sinfo; use Sinfo;
82 with Sinfo.CN; use Sinfo.CN;
83 with Snames; use Snames;
84 with Stringt; use Stringt;
86 with Stylesw; use Stylesw;
87 with Tbuild; use Tbuild;
88 with Uintp; use Uintp;
89 with Urealp; use Urealp;
90 with Validsw; use Validsw;
92 package body Sem_Ch6 is
94 May_Hide_Profile : Boolean := False;
95 -- This flag is used to indicate that two formals in two subprograms being
96 -- checked for conformance differ only in that one is an access parameter
97 -- while the other is of a general access type with the same designated
98 -- type. In this case, if the rest of the signatures match, a call to
99 -- either subprogram may be ambiguous, which is worth a warning. The flag
100 -- is set in Compatible_Types, and the warning emitted in
101 -- New_Overloaded_Entity.
103 -----------------------
104 -- Local Subprograms --
105 -----------------------
107 procedure Analyze_Function_Return (N : Node_Id);
108 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
109 -- applies to a [generic] function.
111 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
112 -- Analyze a generic subprogram body. N is the body to be analyzed, and
113 -- Gen_Id is the defining entity Id for the corresponding spec.
115 procedure Analyze_Null_Procedure
117 Is_Completion : out Boolean);
118 -- A null procedure can be a declaration or (Ada 2012) a completion
120 procedure Analyze_Return_Statement (N : Node_Id);
121 -- Common processing for simple and extended return statements
123 procedure Analyze_Return_Type (N : Node_Id);
124 -- Subsidiary to Process_Formals: analyze subtype mark in function
125 -- specification in a context where the formals are visible and hide
128 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
129 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
130 -- that we can use RETURN but not skip the debug output at the end.
132 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
133 -- Returns true if Subp can override a predefined operator.
135 procedure Check_Conformance
138 Ctype : Conformance_Type;
140 Conforms : out Boolean;
141 Err_Loc : Node_Id := Empty;
142 Get_Inst : Boolean := False;
143 Skip_Controlling_Formals : Boolean := False);
144 -- Given two entities, this procedure checks that the profiles associated
145 -- with these entities meet the conformance criterion given by the third
146 -- parameter. If they conform, Conforms is set True and control returns
147 -- to the caller. If they do not conform, Conforms is set to False, and
148 -- in addition, if Errmsg is True on the call, proper messages are output
149 -- to complain about the conformance failure. If Err_Loc is non_Empty
150 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
151 -- error messages are placed on the appropriate part of the construct
152 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
153 -- against a formal access-to-subprogram type so Get_Instance_Of must
156 procedure Check_Limited_Return
160 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
161 -- types. Used only for simple return statements. Expr is the expression
164 procedure Check_Subprogram_Order (N : Node_Id);
165 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
166 -- the alpha ordering rule for N if this ordering requirement applicable.
168 procedure Check_Returns
172 Proc : Entity_Id := Empty);
173 -- Called to check for missing return statements in a function body, or for
174 -- returns present in a procedure body which has No_Return set. HSS is the
175 -- handled statement sequence for the subprogram body. This procedure
176 -- checks all flow paths to make sure they either have return (Mode = 'F',
177 -- used for functions) or do not have a return (Mode = 'P', used for
178 -- No_Return procedures). The flag Err is set if there are any control
179 -- paths not explicitly terminated by a return in the function case, and is
180 -- True otherwise. Proc is the entity for the procedure case and is used
181 -- in posting the warning message.
183 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
184 -- In Ada 2012, a primitive equality operator on an untagged record type
185 -- must appear before the type is frozen, and have the same visibility as
186 -- that of the type. This procedure checks that this rule is met, and
187 -- otherwise emits an error on the subprogram declaration and a warning
188 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
189 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
190 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
191 -- is set, otherwise the call has no effect.
193 procedure Enter_Overloaded_Entity (S : Entity_Id);
194 -- This procedure makes S, a new overloaded entity, into the first visible
195 -- entity with that name.
197 function Is_Non_Overriding_Operation
199 New_E : Entity_Id) return Boolean;
200 -- Enforce the rule given in 12.3(18): a private operation in an instance
201 -- overrides an inherited operation only if the corresponding operation
202 -- was overriding in the generic. This needs to be checked for primitive
203 -- operations of types derived (in the generic unit) from formal private
204 -- or formal derived types.
206 procedure Make_Inequality_Operator (S : Entity_Id);
207 -- Create the declaration for an inequality operator that is implicitly
208 -- created by a user-defined equality operator that yields a boolean.
210 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
211 -- Formal_Id is an formal parameter entity. This procedure deals with
212 -- setting the proper validity status for this entity, which depends on
213 -- the kind of parameter and the validity checking mode.
215 ---------------------------------------------
216 -- Analyze_Abstract_Subprogram_Declaration --
217 ---------------------------------------------
219 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
220 Scop : constant Entity_Id := Current_Scope;
221 Subp_Id : constant Entity_Id :=
222 Analyze_Subprogram_Specification (Specification (N));
225 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
227 Generate_Definition (Subp_Id);
229 -- Set the SPARK mode from the current context (may be overwritten later
230 -- with explicit pragma).
232 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
233 Set_SPARK_Pragma_Inherited (Subp_Id);
235 -- Preserve relevant elaboration-related attributes of the context which
236 -- are no longer available or very expensive to recompute once analysis,
237 -- resolution, and expansion are over.
239 Mark_Elaboration_Attributes
243 Set_Is_Abstract_Subprogram (Subp_Id);
244 New_Overloaded_Entity (Subp_Id);
245 Check_Delayed_Subprogram (Subp_Id);
247 Set_Categorization_From_Scope (Subp_Id, Scop);
249 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
250 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
252 -- Issue a warning if the abstract subprogram is neither a dispatching
253 -- operation nor an operation that overrides an inherited subprogram or
254 -- predefined operator, since this most likely indicates a mistake.
256 elsif Warn_On_Redundant_Constructs
257 and then not Is_Dispatching_Operation (Subp_Id)
258 and then not Present (Overridden_Operation (Subp_Id))
259 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
260 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
263 ("abstract subprogram is not dispatching or overriding?r?", N);
266 Generate_Reference_To_Formals (Subp_Id);
267 Check_Eliminated (Subp_Id);
269 if Has_Aspects (N) then
270 Analyze_Aspect_Specifications (N, Subp_Id);
272 end Analyze_Abstract_Subprogram_Declaration;
274 ---------------------------------
275 -- Analyze_Expression_Function --
276 ---------------------------------
278 procedure Analyze_Expression_Function (N : Node_Id) is
279 Expr : constant Node_Id := Expression (N);
280 Loc : constant Source_Ptr := Sloc (N);
281 LocX : constant Source_Ptr := Sloc (Expr);
282 Spec : constant Node_Id := Specification (N);
284 procedure Freeze_Expr_Types (Def_Id : Entity_Id);
285 -- N is an expression function that is a completion and Def_Id its
286 -- defining entity. Freeze before N all the types referenced by the
287 -- expression of the function.
289 -----------------------
290 -- Freeze_Expr_Types --
291 -----------------------
293 procedure Freeze_Expr_Types (Def_Id : Entity_Id) is
294 function Cloned_Expression return Node_Id;
295 -- Build a duplicate of the expression of the return statement that
296 -- has no defining entities shared with the original expression.
298 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result;
299 -- Freeze all types referenced in the subtree rooted at Node
301 -----------------------
302 -- Cloned_Expression --
303 -----------------------
305 function Cloned_Expression return Node_Id is
306 function Clone_Id (Node : Node_Id) return Traverse_Result;
307 -- Tree traversal routine that clones the defining identifier of
308 -- iterator and loop parameter specification nodes.
314 function Clone_Id (Node : Node_Id) return Traverse_Result is
316 if Nkind_In (Node, N_Iterator_Specification,
317 N_Loop_Parameter_Specification)
319 Set_Defining_Identifier (Node,
320 New_Copy (Defining_Identifier (Node)));
326 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id);
330 Dup_Expr : constant Node_Id := New_Copy_Tree (Expr);
332 -- Start of processing for Cloned_Expression
335 -- We must duplicate the expression with semantic information to
336 -- inherit the decoration of global entities in generic instances.
337 -- Set the parent of the new node to be the parent of the original
338 -- to get the proper context, which is needed for complete error
339 -- reporting and for semantic analysis.
341 Set_Parent (Dup_Expr, Parent (Expr));
343 -- Replace the defining identifier of iterators and loop param
344 -- specifications by a clone to ensure that the cloned expression
345 -- and the original expression don't have shared identifiers;
346 -- otherwise, as part of the preanalysis of the expression, these
347 -- shared identifiers may be left decorated with itypes which
348 -- will not be available in the tree passed to the backend.
350 Clone_Def_Ids (Dup_Expr);
353 end Cloned_Expression;
355 ----------------------
356 -- Freeze_Type_Refs --
357 ----------------------
359 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is
360 procedure Check_And_Freeze_Type (Typ : Entity_Id);
361 -- Check that Typ is fully declared and freeze it if so
363 ---------------------------
364 -- Check_And_Freeze_Type --
365 ---------------------------
367 procedure Check_And_Freeze_Type (Typ : Entity_Id) is
369 -- Skip Itypes created by the preanalysis, 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 -- If the return expression is a static constant, we suppress warning
788 -- messages on unused formals, which in most cases will be noise.
790 Set_Is_Trivial_Subprogram
791 (Defining_Entity (New_Body), Is_OK_Static_Expression (Expr));
792 end Analyze_Expression_Function;
794 ----------------------------------------
795 -- Analyze_Extended_Return_Statement --
796 ----------------------------------------
798 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
800 Check_Compiler_Unit ("extended return statement", N);
801 Analyze_Return_Statement (N);
802 end Analyze_Extended_Return_Statement;
804 ----------------------------
805 -- Analyze_Function_Call --
806 ----------------------------
808 procedure Analyze_Function_Call (N : Node_Id) is
809 Actuals : constant List_Id := Parameter_Associations (N);
810 Func_Nam : constant Node_Id := Name (N);
816 -- A call of the form A.B (X) may be an Ada 2005 call, which is
817 -- rewritten as B (A, X). If the rewriting is successful, the call
818 -- has been analyzed and we just return.
820 if Nkind (Func_Nam) = N_Selected_Component
821 and then Name (N) /= Func_Nam
822 and then Is_Rewrite_Substitution (N)
823 and then Present (Etype (N))
828 -- If error analyzing name, then set Any_Type as result type and return
830 if Etype (Func_Nam) = Any_Type then
831 Set_Etype (N, Any_Type);
835 -- Otherwise analyze the parameters
837 if Present (Actuals) then
838 Actual := First (Actuals);
839 while Present (Actual) loop
841 Check_Parameterless_Call (Actual);
847 end Analyze_Function_Call;
849 -----------------------------
850 -- Analyze_Function_Return --
851 -----------------------------
853 procedure Analyze_Function_Return (N : Node_Id) is
854 Loc : constant Source_Ptr := Sloc (N);
855 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
856 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
858 R_Type : constant Entity_Id := Etype (Scope_Id);
859 -- Function result subtype
861 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
862 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
863 -- aggregate in a return statement.
865 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
866 -- Check that the return_subtype_indication properly matches the result
867 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
869 -----------------------------------
870 -- Check_Aggregate_Accessibility --
871 -----------------------------------
873 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
874 Typ : constant Entity_Id := Etype (Aggr);
881 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
882 Discr := First_Discriminant (Typ);
883 Assoc := First (Component_Associations (Aggr));
884 while Present (Discr) loop
885 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
886 Expr := Expression (Assoc);
888 if Nkind (Expr) = N_Attribute_Reference
889 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
891 Obj := Prefix (Expr);
892 while Nkind_In (Obj, N_Indexed_Component,
893 N_Selected_Component)
898 -- Do not check aliased formals or function calls. A
899 -- run-time check may still be needed ???
901 if Is_Entity_Name (Obj)
902 and then Comes_From_Source (Obj)
904 if Is_Formal (Entity (Obj))
905 and then Is_Aliased (Entity (Obj))
909 elsif Object_Access_Level (Obj) >
910 Scope_Depth (Scope (Scope_Id))
913 ("access discriminant in return aggregate would "
914 & "be a dangling reference", Obj);
920 Next_Discriminant (Discr);
923 end Check_Aggregate_Accessibility;
925 -------------------------------------
926 -- Check_Return_Subtype_Indication --
927 -------------------------------------
929 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
930 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
932 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
933 -- Subtype given in the extended return statement (must match R_Type)
935 Subtype_Ind : constant Node_Id :=
936 Object_Definition (Original_Node (Obj_Decl));
938 procedure Error_No_Match (N : Node_Id);
939 -- Output error messages for case where types do not statically
940 -- match. N is the location for the messages.
946 procedure Error_No_Match (N : Node_Id) is
949 ("subtype must statically match function result subtype", N);
951 if not Predicates_Match (R_Stm_Type, R_Type) then
952 Error_Msg_Node_2 := R_Type;
954 ("\predicate of& does not match predicate of&",
959 -- Start of processing for Check_Return_Subtype_Indication
962 -- First, avoid cascaded errors
964 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
968 -- "return access T" case; check that the return statement also has
969 -- "access T", and that the subtypes statically match:
970 -- if this is an access to subprogram the signatures must match.
972 if Is_Anonymous_Access_Type (R_Type) then
973 if Is_Anonymous_Access_Type (R_Stm_Type) then
974 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
976 if Base_Type (Designated_Type (R_Stm_Type)) /=
977 Base_Type (Designated_Type (R_Type))
978 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
980 Error_No_Match (Subtype_Mark (Subtype_Ind));
984 -- For two anonymous access to subprogram types, the types
985 -- themselves must be type conformant.
987 if not Conforming_Types
988 (R_Stm_Type, R_Type, Fully_Conformant)
990 Error_No_Match (Subtype_Ind);
995 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
998 -- If the return object is of an anonymous access type, then report
999 -- an error if the function's result type is not also anonymous.
1001 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
1002 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
1004 ("anonymous access not allowed for function with named access "
1005 & "result", Subtype_Ind);
1007 -- Subtype indication case: check that the return object's type is
1008 -- covered by the result type, and that the subtypes statically match
1009 -- when the result subtype is constrained. Also handle record types
1010 -- with unknown discriminants for which we have built the underlying
1011 -- record view. Coverage is needed to allow specific-type return
1012 -- objects when the result type is class-wide (see AI05-32).
1014 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
1015 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1018 (Base_Type (R_Type),
1019 Underlying_Record_View (Base_Type (R_Stm_Type))))
1021 -- A null exclusion may be present on the return type, on the
1022 -- function specification, on the object declaration or on the
1025 if Is_Access_Type (R_Type)
1027 (Can_Never_Be_Null (R_Type)
1028 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1029 Can_Never_Be_Null (R_Stm_Type)
1031 Error_No_Match (Subtype_Ind);
1034 -- AI05-103: for elementary types, subtypes must statically match
1036 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1037 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1038 Error_No_Match (Subtype_Ind);
1042 -- All remaining cases are illegal
1044 -- Note: previous versions of this subprogram allowed the return
1045 -- value to be the ancestor of the return type if the return type
1046 -- was a null extension. This was plainly incorrect.
1050 ("wrong type for return_subtype_indication", Subtype_Ind);
1052 end Check_Return_Subtype_Indication;
1054 ---------------------
1055 -- Local Variables --
1056 ---------------------
1059 Obj_Decl : Node_Id := Empty;
1061 -- Start of processing for Analyze_Function_Return
1064 Set_Return_Present (Scope_Id);
1066 if Nkind (N) = N_Simple_Return_Statement then
1067 Expr := Expression (N);
1069 -- Guard against a malformed expression. The parser may have tried to
1070 -- recover but the node is not analyzable.
1072 if Nkind (Expr) = N_Error then
1073 Set_Etype (Expr, Any_Type);
1074 Expander_Mode_Save_And_Set (False);
1078 -- The resolution of a controlled [extension] aggregate associated
1079 -- with a return statement creates a temporary which needs to be
1080 -- finalized on function exit. Wrap the return statement inside a
1081 -- block so that the finalization machinery can detect this case.
1082 -- This early expansion is done only when the return statement is
1083 -- not part of a handled sequence of statements.
1085 if Nkind_In (Expr, N_Aggregate,
1086 N_Extension_Aggregate)
1087 and then Needs_Finalization (R_Type)
1088 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1091 Make_Block_Statement (Loc,
1092 Handled_Statement_Sequence =>
1093 Make_Handled_Sequence_Of_Statements (Loc,
1094 Statements => New_List (Relocate_Node (N)))));
1102 -- Ada 2005 (AI-251): If the type of the returned object is
1103 -- an access to an interface type then we add an implicit type
1104 -- conversion to force the displacement of the "this" pointer to
1105 -- reference the secondary dispatch table. We cannot delay the
1106 -- generation of this implicit conversion until the expansion
1107 -- because in this case the type resolution changes the decoration
1108 -- of the expression node to match R_Type; by contrast, if the
1109 -- returned object is a class-wide interface type then it is too
1110 -- early to generate here the implicit conversion since the return
1111 -- statement may be rewritten by the expander into an extended
1112 -- return statement whose expansion takes care of adding the
1113 -- implicit type conversion to displace the pointer to the object.
1116 and then Serious_Errors_Detected = 0
1117 and then Is_Access_Type (R_Type)
1118 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1119 and then Is_Interface (Designated_Type (R_Type))
1120 and then Is_Progenitor (Designated_Type (R_Type),
1121 Designated_Type (Etype (Expr)))
1123 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1127 Resolve (Expr, R_Type);
1128 Check_Limited_Return (N, Expr, R_Type);
1130 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
1131 Check_Aggregate_Accessibility (Expr);
1135 -- RETURN only allowed in SPARK as the last statement in function
1137 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1139 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1140 or else Present (Next (N)))
1142 Check_SPARK_05_Restriction
1143 ("RETURN should be the last statement in function", N);
1147 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1148 Obj_Decl := Last (Return_Object_Declarations (N));
1150 -- Analyze parts specific to extended_return_statement:
1153 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1154 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1157 Expr := Expression (Obj_Decl);
1159 -- Note: The check for OK_For_Limited_Init will happen in
1160 -- Analyze_Object_Declaration; we treat it as a normal
1161 -- object declaration.
1163 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1166 Check_Return_Subtype_Indication (Obj_Decl);
1168 if Present (HSS) then
1171 if Present (Exception_Handlers (HSS)) then
1173 -- ???Has_Nested_Block_With_Handler needs to be set.
1174 -- Probably by creating an actual N_Block_Statement.
1175 -- Probably in Expand.
1181 -- Mark the return object as referenced, since the return is an
1182 -- implicit reference of the object.
1184 Set_Referenced (Defining_Identifier (Obj_Decl));
1186 Check_References (Stm_Entity);
1188 -- Check RM 6.5 (5.9/3)
1191 if Ada_Version < Ada_2012 then
1193 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1194 -- Can it really happen (extended return???)
1197 ("aliased only allowed for limited return objects "
1198 & "in Ada 2012??", N);
1200 elsif not Is_Limited_View (R_Type) then
1202 ("aliased only allowed for limited return objects", N);
1208 -- Case of Expr present
1210 if Present (Expr) then
1212 -- Defend against previous errors
1214 if Nkind (Expr) = N_Empty
1215 or else No (Etype (Expr))
1220 -- Apply constraint check. Note that this is done before the implicit
1221 -- conversion of the expression done for anonymous access types to
1222 -- ensure correct generation of the null-excluding check associated
1223 -- with null-excluding expressions found in return statements.
1225 Apply_Constraint_Check (Expr, R_Type);
1227 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1228 -- type, apply an implicit conversion of the expression to that type
1229 -- to force appropriate static and run-time accessibility checks.
1231 if Ada_Version >= Ada_2005
1232 and then Ekind (R_Type) = E_Anonymous_Access_Type
1234 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1235 Analyze_And_Resolve (Expr, R_Type);
1237 -- If this is a local anonymous access to subprogram, the
1238 -- accessibility check can be applied statically. The return is
1239 -- illegal if the access type of the return expression is declared
1240 -- inside of the subprogram (except if it is the subtype indication
1241 -- of an extended return statement).
1243 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1244 if not Comes_From_Source (Current_Scope)
1245 or else Ekind (Current_Scope) = E_Return_Statement
1250 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1252 Error_Msg_N ("cannot return local access to subprogram", N);
1255 -- The expression cannot be of a formal incomplete type
1257 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1258 and then Is_Generic_Type (Etype (Expr))
1261 ("cannot return expression of a formal incomplete type", N);
1264 -- If the result type is class-wide, then check that the return
1265 -- expression's type is not declared at a deeper level than the
1266 -- function (RM05-6.5(5.6/2)).
1268 if Ada_Version >= Ada_2005
1269 and then Is_Class_Wide_Type (R_Type)
1271 if Type_Access_Level (Etype (Expr)) >
1272 Subprogram_Access_Level (Scope_Id)
1275 ("level of return expression type is deeper than "
1276 & "class-wide function!", Expr);
1280 -- Check incorrect use of dynamically tagged expression
1282 if Is_Tagged_Type (R_Type) then
1283 Check_Dynamically_Tagged_Expression
1289 -- ??? A real run-time accessibility check is needed in cases
1290 -- involving dereferences of access parameters. For now we just
1291 -- check the static cases.
1293 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1294 and then Is_Limited_View (Etype (Scope_Id))
1295 and then Object_Access_Level (Expr) >
1296 Subprogram_Access_Level (Scope_Id)
1298 -- Suppress the message in a generic, where the rewriting
1301 if Inside_A_Generic then
1306 Make_Raise_Program_Error (Loc,
1307 Reason => PE_Accessibility_Check_Failed));
1310 Error_Msg_Warn := SPARK_Mode /= On;
1311 Error_Msg_N ("cannot return a local value by reference<<", N);
1312 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1316 if Known_Null (Expr)
1317 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1318 and then Null_Exclusion_Present (Parent (Scope_Id))
1320 Apply_Compile_Time_Constraint_Error
1322 Msg => "(Ada 2005) null not allowed for "
1323 & "null-excluding return??",
1324 Reason => CE_Null_Not_Allowed);
1327 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1328 -- has no initializing expression.
1330 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1331 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1332 Subprogram_Access_Level (Scope_Id)
1335 ("level of return expression type is deeper than "
1336 & "class-wide function!", Obj_Decl);
1339 end Analyze_Function_Return;
1341 -------------------------------------
1342 -- Analyze_Generic_Subprogram_Body --
1343 -------------------------------------
1345 procedure Analyze_Generic_Subprogram_Body
1349 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1350 Kind : constant Entity_Kind := Ekind (Gen_Id);
1351 Body_Id : Entity_Id;
1356 -- Copy body and disable expansion while analyzing the generic For a
1357 -- stub, do not copy the stub (which would load the proper body), this
1358 -- will be done when the proper body is analyzed.
1360 if Nkind (N) /= N_Subprogram_Body_Stub then
1361 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1364 -- Once the contents of the generic copy and the template are
1365 -- swapped, do the same for their respective aspect specifications.
1367 Exchange_Aspects (N, New_N);
1369 -- Collect all contract-related source pragmas found within the
1370 -- template and attach them to the contract of the subprogram body.
1371 -- This contract is used in the capture of global references within
1374 Create_Generic_Contract (N);
1379 Spec := Specification (N);
1381 -- Within the body of the generic, the subprogram is callable, and
1382 -- behaves like the corresponding non-generic unit.
1384 Body_Id := Defining_Entity (Spec);
1386 if Kind = E_Generic_Procedure
1387 and then Nkind (Spec) /= N_Procedure_Specification
1389 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1392 elsif Kind = E_Generic_Function
1393 and then Nkind (Spec) /= N_Function_Specification
1395 Error_Msg_N ("invalid body for generic function ", Body_Id);
1399 Set_Corresponding_Body (Gen_Decl, Body_Id);
1401 if Has_Completion (Gen_Id)
1402 and then Nkind (Parent (N)) /= N_Subunit
1404 Error_Msg_N ("duplicate generic body", N);
1407 Set_Has_Completion (Gen_Id);
1410 if Nkind (N) = N_Subprogram_Body_Stub then
1411 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1413 Set_Corresponding_Spec (N, Gen_Id);
1416 if Nkind (Parent (N)) = N_Compilation_Unit then
1417 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1420 -- Make generic parameters immediately visible in the body. They are
1421 -- needed to process the formals declarations. Then make the formals
1422 -- visible in a separate step.
1424 Push_Scope (Gen_Id);
1428 First_Ent : Entity_Id;
1431 First_Ent := First_Entity (Gen_Id);
1434 while Present (E) and then not Is_Formal (E) loop
1439 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1441 -- Now generic formals are visible, and the specification can be
1442 -- analyzed, for subsequent conformance check.
1444 Body_Id := Analyze_Subprogram_Specification (Spec);
1446 -- Make formal parameters visible
1450 -- E is the first formal parameter, we loop through the formals
1451 -- installing them so that they will be visible.
1453 Set_First_Entity (Gen_Id, E);
1454 while Present (E) loop
1460 -- Visible generic entity is callable within its own body
1462 Set_Ekind (Gen_Id, Ekind (Body_Id));
1463 Set_Ekind (Body_Id, E_Subprogram_Body);
1464 Set_Convention (Body_Id, Convention (Gen_Id));
1465 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1466 Set_Scope (Body_Id, Scope (Gen_Id));
1468 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1470 if Nkind (N) = N_Subprogram_Body_Stub then
1472 -- No body to analyze, so restore state of generic unit
1474 Set_Ekind (Gen_Id, Kind);
1475 Set_Ekind (Body_Id, Kind);
1477 if Present (First_Ent) then
1478 Set_First_Entity (Gen_Id, First_Ent);
1485 -- If this is a compilation unit, it must be made visible explicitly,
1486 -- because the compilation of the declaration, unlike other library
1487 -- unit declarations, does not. If it is not a unit, the following
1488 -- is redundant but harmless.
1490 Set_Is_Immediately_Visible (Gen_Id);
1491 Reference_Body_Formals (Gen_Id, Body_Id);
1493 if Is_Child_Unit (Gen_Id) then
1494 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1497 Set_Actual_Subtypes (N, Current_Scope);
1499 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1500 Set_SPARK_Pragma_Inherited (Body_Id);
1502 -- Analyze any aspect specifications that appear on the generic
1505 if Has_Aspects (N) then
1506 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
1509 Analyze_Declarations (Declarations (N));
1512 -- Process the contract of the subprogram body after all declarations
1513 -- have been analyzed. This ensures that any contract-related pragmas
1514 -- are available through the N_Contract node of the body.
1516 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1518 Analyze (Handled_Statement_Sequence (N));
1519 Save_Global_References (Original_Node (N));
1521 -- Prior to exiting the scope, include generic formals again (if any
1522 -- are present) in the set of local entities.
1524 if Present (First_Ent) then
1525 Set_First_Entity (Gen_Id, First_Ent);
1528 Check_References (Gen_Id);
1531 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1532 Update_Use_Clause_Chain;
1533 Validate_Categorization_Dependency (N, Gen_Id);
1535 Check_Subprogram_Order (N);
1537 -- Outside of its body, unit is generic again
1539 Set_Ekind (Gen_Id, Kind);
1540 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1543 Style.Check_Identifier (Body_Id, Gen_Id);
1547 end Analyze_Generic_Subprogram_Body;
1549 ----------------------------
1550 -- Analyze_Null_Procedure --
1551 ----------------------------
1553 procedure Analyze_Null_Procedure
1555 Is_Completion : out Boolean)
1557 Loc : constant Source_Ptr := Sloc (N);
1558 Spec : constant Node_Id := Specification (N);
1559 Designator : Entity_Id;
1561 Null_Body : Node_Id := Empty;
1562 Null_Stmt : Node_Id := Null_Statement (Spec);
1566 -- Capture the profile of the null procedure before analysis, for
1567 -- expansion at the freeze point and at each point of call. The body is
1568 -- used if the procedure has preconditions, or if it is a completion. In
1569 -- the first case the body is analyzed at the freeze point, in the other
1570 -- it replaces the null procedure declaration.
1572 -- For a null procedure that comes from source, a NULL statement is
1573 -- provided by the parser, which carries the source location of the
1574 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1575 -- from expansion, create one now.
1577 if No (Null_Stmt) then
1578 Null_Stmt := Make_Null_Statement (Loc);
1582 Make_Subprogram_Body (Loc,
1583 Specification => New_Copy_Tree (Spec),
1584 Declarations => New_List,
1585 Handled_Statement_Sequence =>
1586 Make_Handled_Sequence_Of_Statements (Loc,
1587 Statements => New_List (Null_Stmt)));
1589 -- Create new entities for body and formals
1591 Set_Defining_Unit_Name (Specification (Null_Body),
1592 Make_Defining_Identifier
1593 (Sloc (Defining_Entity (N)),
1594 Chars (Defining_Entity (N))));
1596 Form := First (Parameter_Specifications (Specification (Null_Body)));
1597 while Present (Form) loop
1598 Set_Defining_Identifier (Form,
1599 Make_Defining_Identifier
1600 (Sloc (Defining_Identifier (Form)),
1601 Chars (Defining_Identifier (Form))));
1605 -- Determine whether the null procedure may be a completion of a generic
1606 -- suprogram, in which case we use the new null body as the completion
1607 -- and set minimal semantic information on the original declaration,
1608 -- which is rewritten as a null statement.
1610 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1612 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1613 Insert_Before (N, Null_Body);
1614 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1616 Rewrite (N, Make_Null_Statement (Loc));
1617 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1618 Is_Completion := True;
1622 -- Resolve the types of the formals now, because the freeze point may
1623 -- appear in a different context, e.g. an instantiation.
1625 Form := First (Parameter_Specifications (Specification (Null_Body)));
1626 while Present (Form) loop
1627 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1628 Find_Type (Parameter_Type (Form));
1630 elsif No (Access_To_Subprogram_Definition
1631 (Parameter_Type (Form)))
1633 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1635 -- The case of a null procedure with a formal that is an
1636 -- access-to-subprogram type, and that is used as an actual
1637 -- in an instantiation is left to the enthusiastic reader.
1647 -- If there are previous overloadable entities with the same name, check
1648 -- whether any of them is completed by the null procedure.
1650 if Present (Prev) and then Is_Overloadable (Prev) then
1651 Designator := Analyze_Subprogram_Specification (Spec);
1652 Prev := Find_Corresponding_Spec (N);
1655 if No (Prev) or else not Comes_From_Source (Prev) then
1656 Designator := Analyze_Subprogram_Specification (Spec);
1657 Set_Has_Completion (Designator);
1659 -- Signal to caller that this is a procedure declaration
1661 Is_Completion := False;
1663 -- Null procedures are always inlined, but generic formal subprograms
1664 -- which appear as such in the internal instance of formal packages,
1665 -- need no completion and are not marked Inline.
1668 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1670 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1671 Set_Body_To_Inline (N, Null_Body);
1672 Set_Is_Inlined (Designator);
1676 -- The null procedure is a completion. We unconditionally rewrite
1677 -- this as a null body (even if expansion is not active), because
1678 -- there are various error checks that are applied on this body
1679 -- when it is analyzed (e.g. correct aspect placement).
1681 if Has_Completion (Prev) then
1682 Error_Msg_Sloc := Sloc (Prev);
1683 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1686 Check_Previous_Null_Procedure (N, Prev);
1688 Is_Completion := True;
1689 Rewrite (N, Null_Body);
1692 end Analyze_Null_Procedure;
1694 -----------------------------
1695 -- Analyze_Operator_Symbol --
1696 -----------------------------
1698 -- An operator symbol such as "+" or "and" may appear in context where the
1699 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1700 -- is just a string, as in (conjunction = "or"). In these cases the parser
1701 -- generates this node, and the semantics does the disambiguation. Other
1702 -- such case are actuals in an instantiation, the generic unit in an
1703 -- instantiation, and pragma arguments.
1705 procedure Analyze_Operator_Symbol (N : Node_Id) is
1706 Par : constant Node_Id := Parent (N);
1709 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1710 or else Nkind (Par) = N_Function_Instantiation
1711 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1712 or else (Nkind (Par) = N_Pragma_Argument_Association
1713 and then not Is_Pragma_String_Literal (Par))
1714 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1715 or else (Nkind (Par) = N_Attribute_Reference
1716 and then Attribute_Name (Par) /= Name_Value)
1718 Find_Direct_Name (N);
1721 Change_Operator_Symbol_To_String_Literal (N);
1724 end Analyze_Operator_Symbol;
1726 -----------------------------------
1727 -- Analyze_Parameter_Association --
1728 -----------------------------------
1730 procedure Analyze_Parameter_Association (N : Node_Id) is
1732 Analyze (Explicit_Actual_Parameter (N));
1733 end Analyze_Parameter_Association;
1735 ----------------------------
1736 -- Analyze_Procedure_Call --
1737 ----------------------------
1739 -- WARNING: This routine manages Ghost regions. Return statements must be
1740 -- replaced by gotos which jump to the end of the routine and restore the
1743 procedure Analyze_Procedure_Call (N : Node_Id) is
1744 procedure Analyze_Call_And_Resolve;
1745 -- Do Analyze and Resolve calls for procedure call. At the end, check
1746 -- for illegal order dependence.
1747 -- ??? where is the check for illegal order dependencies?
1749 ------------------------------
1750 -- Analyze_Call_And_Resolve --
1751 ------------------------------
1753 procedure Analyze_Call_And_Resolve is
1755 if Nkind (N) = N_Procedure_Call_Statement then
1757 Resolve (N, Standard_Void_Type);
1761 end Analyze_Call_And_Resolve;
1765 Actuals : constant List_Id := Parameter_Associations (N);
1766 Loc : constant Source_Ptr := Sloc (N);
1767 P : constant Node_Id := Name (N);
1769 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1770 -- Save the Ghost mode to restore on exit
1775 -- Start of processing for Analyze_Procedure_Call
1778 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1779 -- a procedure call or an entry call. The prefix may denote an access
1780 -- to subprogram type, in which case an implicit dereference applies.
1781 -- If the prefix is an indexed component (without implicit dereference)
1782 -- then the construct denotes a call to a member of an entire family.
1783 -- If the prefix is a simple name, it may still denote a call to a
1784 -- parameterless member of an entry family. Resolution of these various
1785 -- interpretations is delicate.
1787 -- Do not analyze machine code statements to avoid rejecting them in
1790 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1791 Set_Etype (P, Standard_Void_Type);
1796 -- If this is a call of the form Obj.Op, the call may have been analyzed
1797 -- and possibly rewritten into a block, in which case we are done.
1799 if Analyzed (N) then
1802 -- If there is an error analyzing the name (which may have been
1803 -- rewritten if the original call was in prefix notation) then error
1804 -- has been emitted already, mark node and return.
1806 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1807 Set_Etype (N, Any_Type);
1811 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1812 -- Set the mode now to ensure that any nodes generated during analysis
1813 -- and expansion are properly marked as Ghost.
1815 Mark_And_Set_Ghost_Procedure_Call (N);
1817 -- Otherwise analyze the parameters
1819 if Present (Actuals) then
1820 Actual := First (Actuals);
1822 while Present (Actual) loop
1824 Check_Parameterless_Call (Actual);
1829 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1831 if Nkind (P) = N_Attribute_Reference
1832 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1834 Name_Elab_Subp_Body)
1836 if Present (Actuals) then
1838 ("no parameters allowed for this call", First (Actuals));
1842 Set_Etype (N, Standard_Void_Type);
1845 elsif Is_Entity_Name (P)
1846 and then Is_Record_Type (Etype (Entity (P)))
1847 and then Remote_AST_I_Dereference (P)
1851 elsif Is_Entity_Name (P)
1852 and then Ekind (Entity (P)) /= E_Entry_Family
1854 if Is_Access_Type (Etype (P))
1855 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1856 and then No (Actuals)
1857 and then Comes_From_Source (N)
1859 Error_Msg_N ("missing explicit dereference in call", N);
1862 Analyze_Call_And_Resolve;
1864 -- If the prefix is the simple name of an entry family, this is a
1865 -- parameterless call from within the task body itself.
1867 elsif Is_Entity_Name (P)
1868 and then Nkind (P) = N_Identifier
1869 and then Ekind (Entity (P)) = E_Entry_Family
1870 and then Present (Actuals)
1871 and then No (Next (First (Actuals)))
1873 -- Can be call to parameterless entry family. What appears to be the
1874 -- sole argument is in fact the entry index. Rewrite prefix of node
1875 -- accordingly. Source representation is unchanged by this
1879 Make_Indexed_Component (Loc,
1881 Make_Selected_Component (Loc,
1882 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1883 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1884 Expressions => Actuals);
1885 Set_Name (N, New_N);
1886 Set_Etype (New_N, Standard_Void_Type);
1887 Set_Parameter_Associations (N, No_List);
1888 Analyze_Call_And_Resolve;
1890 elsif Nkind (P) = N_Explicit_Dereference then
1891 if Ekind (Etype (P)) = E_Subprogram_Type then
1892 Analyze_Call_And_Resolve;
1894 Error_Msg_N ("expect access to procedure in call", P);
1897 -- The name can be a selected component or an indexed component that
1898 -- yields an access to subprogram. Such a prefix is legal if the call
1899 -- has parameter associations.
1901 elsif Is_Access_Type (Etype (P))
1902 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1904 if Present (Actuals) then
1905 Analyze_Call_And_Resolve;
1907 Error_Msg_N ("missing explicit dereference in call ", N);
1910 -- If not an access to subprogram, then the prefix must resolve to the
1911 -- name of an entry, entry family, or protected operation.
1913 -- For the case of a simple entry call, P is a selected component where
1914 -- the prefix is the task and the selector name is the entry. A call to
1915 -- a protected procedure will have the same syntax. If the protected
1916 -- object contains overloaded operations, the entity may appear as a
1917 -- function, the context will select the operation whose type is Void.
1919 elsif Nkind (P) = N_Selected_Component
1920 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1924 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1925 -- in prefix notation may still be missing its controlling argument,
1926 -- so perform the transformation now.
1928 if SPARK_Mode = On and then In_Inlined_Body then
1930 Subp : constant Entity_Id := Entity (Selector_Name (P));
1931 Typ : constant Entity_Id := Etype (Prefix (P));
1934 if Is_Tagged_Type (Typ)
1935 and then Present (First_Formal (Subp))
1936 and then Etype (First_Formal (Subp)) = Typ
1937 and then Try_Object_Operation (P)
1942 Analyze_Call_And_Resolve;
1947 Analyze_Call_And_Resolve;
1950 elsif Nkind (P) = N_Selected_Component
1951 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1952 and then Present (Actuals)
1953 and then No (Next (First (Actuals)))
1955 -- Can be call to parameterless entry family. What appears to be the
1956 -- sole argument is in fact the entry index. Rewrite prefix of node
1957 -- accordingly. Source representation is unchanged by this
1961 Make_Indexed_Component (Loc,
1962 Prefix => New_Copy (P),
1963 Expressions => Actuals);
1964 Set_Name (N, New_N);
1965 Set_Etype (New_N, Standard_Void_Type);
1966 Set_Parameter_Associations (N, No_List);
1967 Analyze_Call_And_Resolve;
1969 -- For the case of a reference to an element of an entry family, P is
1970 -- an indexed component whose prefix is a selected component (task and
1971 -- entry family), and whose index is the entry family index.
1973 elsif Nkind (P) = N_Indexed_Component
1974 and then Nkind (Prefix (P)) = N_Selected_Component
1975 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1977 Analyze_Call_And_Resolve;
1979 -- If the prefix is the name of an entry family, it is a call from
1980 -- within the task body itself.
1982 elsif Nkind (P) = N_Indexed_Component
1983 and then Nkind (Prefix (P)) = N_Identifier
1984 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1987 Make_Selected_Component (Loc,
1989 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1990 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1991 Rewrite (Prefix (P), New_N);
1993 Analyze_Call_And_Resolve;
1995 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1996 -- procedure name, so the construct can only be a qualified expression.
1998 elsif Nkind (P) = N_Qualified_Expression
1999 and then Ada_Version >= Ada_2012
2001 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
2004 -- Anything else is an error
2007 Error_Msg_N ("invalid procedure or entry call", N);
2011 Restore_Ghost_Mode (Saved_GM);
2012 end Analyze_Procedure_Call;
2014 ------------------------------
2015 -- Analyze_Return_Statement --
2016 ------------------------------
2018 procedure Analyze_Return_Statement (N : Node_Id) is
2019 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2020 N_Simple_Return_Statement));
2022 Returns_Object : constant Boolean :=
2023 Nkind (N) = N_Extended_Return_Statement
2025 (Nkind (N) = N_Simple_Return_Statement
2026 and then Present (Expression (N)));
2027 -- True if we're returning something; that is, "return <expression>;"
2028 -- or "return Result : T [:= ...]". False for "return;". Used for error
2029 -- checking: If Returns_Object is True, N should apply to a function
2030 -- body; otherwise N should apply to a procedure body, entry body,
2031 -- accept statement, or extended return statement.
2033 function Find_What_It_Applies_To return Entity_Id;
2034 -- Find the entity representing the innermost enclosing body, accept
2035 -- statement, or extended return statement. If the result is a callable
2036 -- construct or extended return statement, then this will be the value
2037 -- of the Return_Applies_To attribute. Otherwise, the program is
2038 -- illegal. See RM-6.5(4/2).
2040 -----------------------------
2041 -- Find_What_It_Applies_To --
2042 -----------------------------
2044 function Find_What_It_Applies_To return Entity_Id is
2045 Result : Entity_Id := Empty;
2048 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2049 -- and postconditions.
2051 for J in reverse 0 .. Scope_Stack.Last loop
2052 Result := Scope_Stack.Table (J).Entity;
2053 exit when not Ekind_In (Result, E_Block, E_Loop)
2054 and then Chars (Result) /= Name_uPostconditions;
2057 pragma Assert (Present (Result));
2059 end Find_What_It_Applies_To;
2061 -- Local declarations
2063 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2064 Kind : constant Entity_Kind := Ekind (Scope_Id);
2065 Loc : constant Source_Ptr := Sloc (N);
2066 Stm_Entity : constant Entity_Id :=
2068 (E_Return_Statement, Current_Scope, Loc, 'R');
2070 -- Start of processing for Analyze_Return_Statement
2073 Set_Return_Statement_Entity (N, Stm_Entity);
2075 Set_Etype (Stm_Entity, Standard_Void_Type);
2076 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2078 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2079 -- (4/2): an inner return statement will apply to this extended return.
2081 if Nkind (N) = N_Extended_Return_Statement then
2082 Push_Scope (Stm_Entity);
2085 -- Check that pragma No_Return is obeyed. Don't complain about the
2086 -- implicitly-generated return that is placed at the end.
2088 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2089 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2092 -- Warn on any unassigned OUT parameters if in procedure
2094 if Ekind (Scope_Id) = E_Procedure then
2095 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2098 -- Check that functions return objects, and other things do not
2100 if Kind = E_Function or else Kind = E_Generic_Function then
2101 if not Returns_Object then
2102 Error_Msg_N ("missing expression in return from function", N);
2105 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2106 if Returns_Object then
2107 Error_Msg_N ("procedure cannot return value (use function)", N);
2110 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2111 if Returns_Object then
2112 if Is_Protected_Type (Scope (Scope_Id)) then
2113 Error_Msg_N ("entry body cannot return value", N);
2115 Error_Msg_N ("accept statement cannot return value", N);
2119 elsif Kind = E_Return_Statement then
2121 -- We are nested within another return statement, which must be an
2122 -- extended_return_statement.
2124 if Returns_Object then
2125 if Nkind (N) = N_Extended_Return_Statement then
2127 ("extended return statement cannot be nested (use `RETURN;`)",
2130 -- Case of a simple return statement with a value inside extended
2131 -- return statement.
2135 ("return nested in extended return statement cannot return "
2136 & "value (use `RETURN;`)", N);
2141 Error_Msg_N ("illegal context for return statement", N);
2144 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2145 Analyze_Function_Return (N);
2147 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2148 Set_Return_Present (Scope_Id);
2151 if Nkind (N) = N_Extended_Return_Statement then
2155 Kill_Current_Values (Last_Assignment_Only => True);
2156 Check_Unreachable_Code (N);
2158 Analyze_Dimension (N);
2159 end Analyze_Return_Statement;
2161 -------------------------------------
2162 -- Analyze_Simple_Return_Statement --
2163 -------------------------------------
2165 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2167 if Present (Expression (N)) then
2168 Mark_Coextensions (N, Expression (N));
2171 Analyze_Return_Statement (N);
2172 end Analyze_Simple_Return_Statement;
2174 -------------------------
2175 -- Analyze_Return_Type --
2176 -------------------------
2178 procedure Analyze_Return_Type (N : Node_Id) is
2179 Designator : constant Entity_Id := Defining_Entity (N);
2180 Typ : Entity_Id := Empty;
2183 -- Normal case where result definition does not indicate an error
2185 if Result_Definition (N) /= Error then
2186 if Nkind (Result_Definition (N)) = N_Access_Definition then
2187 Check_SPARK_05_Restriction
2188 ("access result is not allowed", Result_Definition (N));
2190 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2193 AD : constant Node_Id :=
2194 Access_To_Subprogram_Definition (Result_Definition (N));
2196 if Present (AD) and then Protected_Present (AD) then
2197 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2199 Typ := Access_Definition (N, Result_Definition (N));
2203 Set_Parent (Typ, Result_Definition (N));
2204 Set_Is_Local_Anonymous_Access (Typ);
2205 Set_Etype (Designator, Typ);
2207 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2209 Null_Exclusion_Static_Checks (N);
2211 -- Subtype_Mark case
2214 Find_Type (Result_Definition (N));
2215 Typ := Entity (Result_Definition (N));
2216 Set_Etype (Designator, Typ);
2218 -- Unconstrained array as result is not allowed in SPARK
2220 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2221 Check_SPARK_05_Restriction
2222 ("returning an unconstrained array is not allowed",
2223 Result_Definition (N));
2226 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2228 Null_Exclusion_Static_Checks (N);
2230 -- If a null exclusion is imposed on the result type, then create
2231 -- a null-excluding itype (an access subtype) and use it as the
2232 -- function's Etype. Note that the null exclusion checks are done
2233 -- right before this, because they don't get applied to types that
2234 -- do not come from source.
2236 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2237 Set_Etype (Designator,
2238 Create_Null_Excluding_Itype
2241 Scope_Id => Scope (Current_Scope)));
2243 -- The new subtype must be elaborated before use because
2244 -- it is visible outside of the function. However its base
2245 -- type may not be frozen yet, so the reference that will
2246 -- force elaboration must be attached to the freezing of
2249 -- If the return specification appears on a proper body,
2250 -- the subtype will have been created already on the spec.
2252 if Is_Frozen (Typ) then
2253 if Nkind (Parent (N)) = N_Subprogram_Body
2254 and then Nkind (Parent (Parent (N))) = N_Subunit
2258 Build_Itype_Reference (Etype (Designator), Parent (N));
2262 Ensure_Freeze_Node (Typ);
2265 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2267 Set_Itype (IR, Etype (Designator));
2268 Append_Freeze_Actions (Typ, New_List (IR));
2273 Set_Etype (Designator, Typ);
2276 if Ekind (Typ) = E_Incomplete_Type
2277 or else (Is_Class_Wide_Type (Typ)
2278 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2280 -- AI05-0151: Tagged incomplete types are allowed in all formal
2281 -- parts. Untagged incomplete types are not allowed in bodies.
2282 -- As a consequence, limited views cannot appear in a basic
2283 -- declaration that is itself within a body, because there is
2284 -- no point at which the non-limited view will become visible.
2286 if Ada_Version >= Ada_2012 then
2287 if From_Limited_With (Typ) and then In_Package_Body then
2289 ("invalid use of incomplete type&",
2290 Result_Definition (N), Typ);
2292 -- The return type of a subprogram body cannot be of a
2293 -- formal incomplete type.
2295 elsif Is_Generic_Type (Typ)
2296 and then Nkind (Parent (N)) = N_Subprogram_Body
2299 ("return type cannot be a formal incomplete type",
2300 Result_Definition (N));
2302 elsif Is_Class_Wide_Type (Typ)
2303 and then Is_Generic_Type (Root_Type (Typ))
2304 and then Nkind (Parent (N)) = N_Subprogram_Body
2307 ("return type cannot be a formal incomplete type",
2308 Result_Definition (N));
2310 elsif Is_Tagged_Type (Typ) then
2313 -- Use is legal in a thunk generated for an operation
2314 -- inherited from a progenitor.
2316 elsif Is_Thunk (Designator)
2317 and then Present (Non_Limited_View (Typ))
2321 elsif Nkind (Parent (N)) = N_Subprogram_Body
2322 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2326 ("invalid use of untagged incomplete type&",
2330 -- The type must be completed in the current package. This
2331 -- is checked at the end of the package declaration when
2332 -- Taft-amendment types are identified. If the return type
2333 -- is class-wide, there is no required check, the type can
2334 -- be a bona fide TAT.
2336 if Ekind (Scope (Current_Scope)) = E_Package
2337 and then In_Private_Part (Scope (Current_Scope))
2338 and then not Is_Class_Wide_Type (Typ)
2340 Append_Elmt (Designator, Private_Dependents (Typ));
2345 ("invalid use of incomplete type&", Designator, Typ);
2350 -- Case where result definition does indicate an error
2353 Set_Etype (Designator, Any_Type);
2355 end Analyze_Return_Type;
2357 -----------------------------
2358 -- Analyze_Subprogram_Body --
2359 -----------------------------
2361 procedure Analyze_Subprogram_Body (N : Node_Id) is
2362 Loc : constant Source_Ptr := Sloc (N);
2363 Body_Spec : constant Node_Id := Specification (N);
2364 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2367 if Debug_Flag_C then
2368 Write_Str ("==> subprogram body ");
2369 Write_Name (Chars (Body_Id));
2370 Write_Str (" from ");
2371 Write_Location (Loc);
2376 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2378 -- The real work is split out into the helper, so it can do "return;"
2379 -- without skipping the debug output:
2381 Analyze_Subprogram_Body_Helper (N);
2383 if Debug_Flag_C then
2385 Write_Str ("<== subprogram body ");
2386 Write_Name (Chars (Body_Id));
2387 Write_Str (" from ");
2388 Write_Location (Loc);
2391 end Analyze_Subprogram_Body;
2393 ------------------------------------
2394 -- Analyze_Subprogram_Body_Helper --
2395 ------------------------------------
2397 -- This procedure is called for regular subprogram bodies, generic bodies,
2398 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2399 -- specification matters, and is used to create a proper declaration for
2400 -- the subprogram, or to perform conformance checks.
2402 -- WARNING: This routine manages Ghost regions. Return statements must be
2403 -- replaced by gotos which jump to the end of the routine and restore the
2406 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2407 Body_Spec : Node_Id := Specification (N);
2408 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2409 Loc : constant Source_Ptr := Sloc (N);
2410 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2412 Conformant : Boolean;
2413 Desig_View : Entity_Id := Empty;
2414 Exch_Views : Elist_Id := No_Elist;
2416 Mask_Types : Elist_Id := No_Elist;
2417 Prot_Typ : Entity_Id := Empty;
2418 Spec_Decl : Node_Id := Empty;
2419 Spec_Id : Entity_Id;
2421 Last_Real_Spec_Entity : Entity_Id := Empty;
2422 -- When we analyze a separate spec, the entity chain ends up containing
2423 -- the formals, as well as any itypes generated during analysis of the
2424 -- default expressions for parameters, or the arguments of associated
2425 -- precondition/postcondition pragmas (which are analyzed in the context
2426 -- of the spec since they have visibility on formals).
2428 -- These entities belong with the spec and not the body. However we do
2429 -- the analysis of the body in the context of the spec (again to obtain
2430 -- visibility to the formals), and all the entities generated during
2431 -- this analysis end up also chained to the entity chain of the spec.
2432 -- But they really belong to the body, and there is circuitry to move
2433 -- them from the spec to the body.
2435 -- However, when we do this move, we don't want to move the real spec
2436 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2437 -- variable points to the last real spec entity, so we only move those
2438 -- chained beyond that point. It is initialized to Empty to deal with
2439 -- the case where there is no separate spec.
2441 function Body_Has_Contract return Boolean;
2442 -- Check whether unanalyzed body has an aspect or pragma that may
2443 -- generate a SPARK contract.
2445 function Body_Has_SPARK_Mode_On return Boolean;
2446 -- Check whether SPARK_Mode On applies to the subprogram body, either
2447 -- because it is specified directly on the body, or because it is
2448 -- inherited from the enclosing subprogram or package.
2450 procedure Build_Subprogram_Declaration;
2451 -- Create a matching subprogram declaration for subprogram body N
2453 procedure Check_Anonymous_Return;
2454 -- Ada 2005: if a function returns an access type that denotes a task,
2455 -- or a type that contains tasks, we must create a master entity for
2456 -- the anonymous type, which typically will be used in an allocator
2457 -- in the body of the function.
2459 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2460 -- Look ahead to recognize a pragma that may appear after the body.
2461 -- If there is a previous spec, check that it appears in the same
2462 -- declarative part. If the pragma is Inline_Always, perform inlining
2463 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2464 -- If the body acts as a spec, and inlining is required, we create a
2465 -- subprogram declaration for it, in order to attach the body to inline.
2466 -- If pragma does not appear after the body, check whether there is
2467 -- an inline pragma before any local declarations.
2469 procedure Check_Missing_Return;
2470 -- Checks for a function with a no return statements, and also performs
2471 -- the warning checks implemented by Check_Returns. In formal mode, also
2472 -- verify that a function ends with a RETURN and that a procedure does
2473 -- not contain any RETURN.
2475 function Disambiguate_Spec return Entity_Id;
2476 -- When a primitive is declared between the private view and the full
2477 -- view of a concurrent type which implements an interface, a special
2478 -- mechanism is used to find the corresponding spec of the primitive
2481 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2482 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2483 -- incomplete types coming from a limited context and replace their
2484 -- limited views with the non-limited ones. Return the list of changes
2485 -- to be used to undo the transformation.
2487 function Is_Private_Concurrent_Primitive
2488 (Subp_Id : Entity_Id) return Boolean;
2489 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2490 -- type that implements an interface and has a private view.
2492 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2493 -- N is the body generated for an expression function that is not a
2494 -- completion and Spec_Id the defining entity of its spec. Mark all
2495 -- the not-yet-frozen types referenced by the simple return statement
2496 -- of the function as formally frozen.
2498 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2499 -- Undo the transformation done by Exchange_Limited_Views.
2501 procedure Set_Trivial_Subprogram (N : Node_Id);
2502 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2503 -- subprogram whose body is being analyzed. N is the statement node
2504 -- causing the flag to be set, if the following statement is a return
2505 -- of an entity, we mark the entity as set in source to suppress any
2506 -- warning on the stylized use of function stubs with a dummy return.
2508 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2509 -- Undo the transformation done by Mask_Unfrozen_Types
2511 procedure Verify_Overriding_Indicator;
2512 -- If there was a previous spec, the entity has been entered in the
2513 -- current scope previously. If the body itself carries an overriding
2514 -- indicator, check that it is consistent with the known status of the
2517 -----------------------
2518 -- Body_Has_Contract --
2519 -----------------------
2521 function Body_Has_Contract return Boolean is
2522 Decls : constant List_Id := Declarations (N);
2526 -- Check for aspects that may generate a contract
2528 if Present (Aspect_Specifications (N)) then
2529 Item := First (Aspect_Specifications (N));
2530 while Present (Item) loop
2531 if Is_Subprogram_Contract_Annotation (Item) then
2539 -- Check for pragmas that may generate a contract
2541 if Present (Decls) then
2542 Item := First (Decls);
2543 while Present (Item) loop
2544 if Nkind (Item) = N_Pragma
2545 and then Is_Subprogram_Contract_Annotation (Item)
2555 end Body_Has_Contract;
2557 ----------------------------
2558 -- Body_Has_SPARK_Mode_On --
2559 ----------------------------
2561 function Body_Has_SPARK_Mode_On return Boolean is
2562 Decls : constant List_Id := Declarations (N);
2566 -- Check for SPARK_Mode aspect
2568 if Present (Aspect_Specifications (N)) then
2569 Item := First (Aspect_Specifications (N));
2570 while Present (Item) loop
2571 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2572 return Get_SPARK_Mode_From_Annotation (Item) = On;
2579 -- Check for SPARK_Mode pragma
2581 if Present (Decls) then
2582 Item := First (Decls);
2583 while Present (Item) loop
2585 -- Pragmas that apply to a subprogram body are usually grouped
2586 -- together. Look for a potential pragma SPARK_Mode among them.
2588 if Nkind (Item) = N_Pragma then
2589 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2590 return Get_SPARK_Mode_From_Annotation (Item) = On;
2593 -- Otherwise the first non-pragma declarative item terminates
2594 -- the region where pragma SPARK_Mode may appear.
2604 -- Otherwise, the applicable SPARK_Mode is inherited from the
2605 -- enclosing subprogram or package.
2607 return SPARK_Mode = On;
2608 end Body_Has_SPARK_Mode_On;
2610 ----------------------------------
2611 -- Build_Subprogram_Declaration --
2612 ----------------------------------
2614 procedure Build_Subprogram_Declaration is
2615 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2616 -- Relocate certain categorization pragmas from the declarative list
2617 -- of subprogram body From and insert them after node To. The pragmas
2620 -- Volatile_Function
2621 -- Also copy pragma SPARK_Mode if present in the declarative list
2622 -- of subprogram body From and insert it after node To. This pragma
2623 -- should not be moved, as it applies to the body too.
2629 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2631 Next_Decl : Node_Id;
2634 pragma Assert (Nkind (From) = N_Subprogram_Body);
2636 -- The destination node must be part of a list, as the pragmas are
2637 -- inserted after it.
2639 pragma Assert (Is_List_Member (To));
2641 -- Inspect the declarations of the subprogram body looking for
2642 -- specific pragmas.
2644 Decl := First (Declarations (N));
2645 while Present (Decl) loop
2646 Next_Decl := Next (Decl);
2648 if Nkind (Decl) = N_Pragma then
2649 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2650 Insert_After (To, New_Copy_Tree (Decl));
2652 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2654 Name_Volatile_Function)
2657 Insert_After (To, Decl);
2668 Subp_Decl : Node_Id;
2670 -- Start of processing for Build_Subprogram_Declaration
2673 -- Create a matching subprogram spec using the profile of the body.
2674 -- The structure of the tree is identical, but has new entities for
2675 -- the defining unit name and formal parameters.
2678 Make_Subprogram_Declaration (Loc,
2679 Specification => Copy_Subprogram_Spec (Body_Spec));
2680 Set_Comes_From_Source (Subp_Decl, True);
2682 -- Relocate the aspects and relevant pragmas from the subprogram body
2683 -- to the generated spec because it acts as the initial declaration.
2685 Insert_Before (N, Subp_Decl);
2686 Move_Aspects (N, To => Subp_Decl);
2687 Move_Pragmas (N, To => Subp_Decl);
2689 -- Ensure that the generated corresponding spec and original body
2690 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2691 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2692 -- correctly set for local subprograms.
2694 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2696 Analyze (Subp_Decl);
2698 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2699 -- the body since the expander may generate calls using that entity.
2700 -- Required to ensure that Expand_Call rewrites calls to this
2701 -- function by calls to the built procedure.
2703 if Modify_Tree_For_C
2704 and then Nkind (Body_Spec) = N_Function_Specification
2706 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2708 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2709 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2710 Corresponding_Procedure
2711 (Defining_Entity (Specification (Subp_Decl))));
2714 -- Analyze any relocated source pragmas or pragmas created for aspect
2717 Decl := Next (Subp_Decl);
2718 while Present (Decl) loop
2720 -- Stop the search for pragmas once the body has been reached as
2721 -- this terminates the region where pragmas may appear.
2726 elsif Nkind (Decl) = N_Pragma then
2733 Spec_Id := Defining_Entity (Subp_Decl);
2734 Set_Corresponding_Spec (N, Spec_Id);
2736 -- Mark the generated spec as a source construct to ensure that all
2737 -- calls to it are properly registered in ALI files for GNATprove.
2739 Set_Comes_From_Source (Spec_Id, True);
2741 -- Ensure that the specs of the subprogram declaration and its body
2742 -- are identical, otherwise they will appear non-conformant due to
2743 -- rewritings in the default values of formal parameters.
2745 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2746 Set_Specification (N, Body_Spec);
2747 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2748 end Build_Subprogram_Declaration;
2750 ----------------------------
2751 -- Check_Anonymous_Return --
2752 ----------------------------
2754 procedure Check_Anonymous_Return is
2760 if Present (Spec_Id) then
2766 if Ekind (Scop) = E_Function
2767 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2768 and then not Is_Thunk (Scop)
2770 -- Skip internally built functions which handle the case of
2771 -- a null access (see Expand_Interface_Conversion)
2773 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2774 and then not Comes_From_Source (Parent (Scop)))
2776 and then (Has_Task (Designated_Type (Etype (Scop)))
2778 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2780 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2781 and then Expander_Active
2783 -- Avoid cases with no tasking support
2785 and then RTE_Available (RE_Current_Master)
2786 and then not Restriction_Active (No_Task_Hierarchy)
2789 Make_Object_Declaration (Loc,
2790 Defining_Identifier =>
2791 Make_Defining_Identifier (Loc, Name_uMaster),
2792 Constant_Present => True,
2793 Object_Definition =>
2794 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2796 Make_Explicit_Dereference (Loc,
2797 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2799 if Present (Declarations (N)) then
2800 Prepend (Decl, Declarations (N));
2802 Set_Declarations (N, New_List (Decl));
2805 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2806 Set_Has_Master_Entity (Scop);
2808 -- Now mark the containing scope as a task master
2811 while Nkind (Par) /= N_Compilation_Unit loop
2812 Par := Parent (Par);
2813 pragma Assert (Present (Par));
2815 -- If we fall off the top, we are at the outer level, and
2816 -- the environment task is our effective master, so nothing
2820 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2822 Set_Is_Task_Master (Par, True);
2827 end Check_Anonymous_Return;
2829 -------------------------
2830 -- Check_Inline_Pragma --
2831 -------------------------
2833 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2837 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2838 -- True when N is a pragma Inline or Inline_Always that applies
2839 -- to this subprogram.
2841 -----------------------
2842 -- Is_Inline_Pragma --
2843 -----------------------
2845 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2847 if Nkind (N) = N_Pragma
2849 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2850 or else (Pragma_Name_Unmapped (N) = Name_Inline
2852 (Front_End_Inlining or else Optimization_Level > 0)))
2853 and then Present (Pragma_Argument_Associations (N))
2856 Pragma_Arg : Node_Id :=
2857 Expression (First (Pragma_Argument_Associations (N)));
2859 if Nkind (Pragma_Arg) = N_Selected_Component then
2860 Pragma_Arg := Selector_Name (Pragma_Arg);
2863 return Chars (Pragma_Arg) = Chars (Body_Id);
2869 end Is_Inline_Pragma;
2871 -- Start of processing for Check_Inline_Pragma
2874 if not Expander_Active then
2878 if Is_List_Member (N)
2879 and then Present (Next (N))
2880 and then Is_Inline_Pragma (Next (N))
2884 elsif Nkind (N) /= N_Subprogram_Body_Stub
2885 and then Present (Declarations (N))
2886 and then Is_Inline_Pragma (First (Declarations (N)))
2888 Prag := First (Declarations (N));
2894 if Present (Prag) then
2895 if Present (Spec_Id) then
2896 if Is_List_Member (N)
2897 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2898 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2904 -- Create a subprogram declaration, to make treatment uniform.
2905 -- Make the sloc of the subprogram name that of the entity in
2906 -- the body, so that style checks find identical strings.
2909 Subp : constant Entity_Id :=
2910 Make_Defining_Identifier
2911 (Sloc (Body_Id), Chars (Body_Id));
2912 Decl : constant Node_Id :=
2913 Make_Subprogram_Declaration (Loc,
2915 New_Copy_Tree (Specification (N)));
2918 -- Link the body and the generated spec
2920 Set_Corresponding_Body (Decl, Body_Id);
2921 Set_Corresponding_Spec (N, Subp);
2923 Set_Defining_Unit_Name (Specification (Decl), Subp);
2925 -- To ensure proper coverage when body is inlined, indicate
2926 -- whether the subprogram comes from source.
2928 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2930 if Present (First_Formal (Body_Id)) then
2931 Plist := Copy_Parameter_List (Body_Id);
2932 Set_Parameter_Specifications
2933 (Specification (Decl), Plist);
2936 -- Move aspects to the new spec
2938 if Has_Aspects (N) then
2939 Move_Aspects (N, To => Decl);
2942 Insert_Before (N, Decl);
2945 Set_Has_Pragma_Inline (Subp);
2947 if Pragma_Name (Prag) = Name_Inline_Always then
2948 Set_Is_Inlined (Subp);
2949 Set_Has_Pragma_Inline_Always (Subp);
2952 -- Prior to copying the subprogram body to create a template
2953 -- for it for subsequent inlining, remove the pragma from
2954 -- the current body so that the copy that will produce the
2955 -- new body will start from a completely unanalyzed tree.
2957 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2958 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2965 end Check_Inline_Pragma;
2967 --------------------------
2968 -- Check_Missing_Return --
2969 --------------------------
2971 procedure Check_Missing_Return is
2973 Missing_Ret : Boolean;
2976 if Nkind (Body_Spec) = N_Function_Specification then
2977 if Present (Spec_Id) then
2983 if Return_Present (Id) then
2984 Check_Returns (HSS, 'F', Missing_Ret);
2987 Set_Has_Missing_Return (Id);
2990 -- Within a premature instantiation of a package with no body, we
2991 -- build completions of the functions therein, with a Raise
2992 -- statement. No point in complaining about a missing return in
2995 elsif Ekind (Id) = E_Function
2996 and then In_Instance
2997 and then Present (Statements (HSS))
2998 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3002 elsif Is_Generic_Subprogram (Id)
3003 or else not Is_Machine_Code_Subprogram (Id)
3005 Error_Msg_N ("missing RETURN statement in function body", N);
3008 -- If procedure with No_Return, check returns
3010 elsif Nkind (Body_Spec) = N_Procedure_Specification
3011 and then Present (Spec_Id)
3012 and then No_Return (Spec_Id)
3014 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
3017 -- Special checks in SPARK mode
3019 if Nkind (Body_Spec) = N_Function_Specification then
3021 -- In SPARK mode, last statement of a function should be a return
3024 Stat : constant Node_Id := Last_Source_Statement (HSS);
3027 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3028 N_Extended_Return_Statement)
3030 Check_SPARK_05_Restriction
3031 ("last statement in function should be RETURN", Stat);
3035 -- In SPARK mode, verify that a procedure has no return
3037 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3038 if Present (Spec_Id) then
3044 -- Would be nice to point to return statement here, can we
3045 -- borrow the Check_Returns procedure here ???
3047 if Return_Present (Id) then
3048 Check_SPARK_05_Restriction
3049 ("procedure should not have RETURN", N);
3052 end Check_Missing_Return;
3054 -----------------------
3055 -- Disambiguate_Spec --
3056 -----------------------
3058 function Disambiguate_Spec return Entity_Id is
3059 Priv_Spec : Entity_Id;
3062 procedure Replace_Types (To_Corresponding : Boolean);
3063 -- Depending on the flag, replace the type of formal parameters of
3064 -- Body_Id if it is a concurrent type implementing interfaces with
3065 -- the corresponding record type or the other way around.
3067 procedure Replace_Types (To_Corresponding : Boolean) is
3069 Formal_Typ : Entity_Id;
3072 Formal := First_Formal (Body_Id);
3073 while Present (Formal) loop
3074 Formal_Typ := Etype (Formal);
3076 if Is_Class_Wide_Type (Formal_Typ) then
3077 Formal_Typ := Root_Type (Formal_Typ);
3080 -- From concurrent type to corresponding record
3082 if To_Corresponding then
3083 if Is_Concurrent_Type (Formal_Typ)
3084 and then Present (Corresponding_Record_Type (Formal_Typ))
3087 (Corresponding_Record_Type (Formal_Typ)))
3090 Corresponding_Record_Type (Formal_Typ));
3093 -- From corresponding record to concurrent type
3096 if Is_Concurrent_Record_Type (Formal_Typ)
3097 and then Present (Interfaces (Formal_Typ))
3100 Corresponding_Concurrent_Type (Formal_Typ));
3104 Next_Formal (Formal);
3108 -- Start of processing for Disambiguate_Spec
3111 -- Try to retrieve the specification of the body as is. All error
3112 -- messages are suppressed because the body may not have a spec in
3113 -- its current state.
3115 Spec_N := Find_Corresponding_Spec (N, False);
3117 -- It is possible that this is the body of a primitive declared
3118 -- between a private and a full view of a concurrent type. The
3119 -- controlling parameter of the spec carries the concurrent type,
3120 -- not the corresponding record type as transformed by Analyze_
3121 -- Subprogram_Specification. In such cases, we undo the change
3122 -- made by the analysis of the specification and try to find the
3125 -- Note that wrappers already have their corresponding specs and
3126 -- bodies set during their creation, so if the candidate spec is
3127 -- a wrapper, then we definitely need to swap all types to their
3128 -- original concurrent status.
3131 or else Is_Primitive_Wrapper (Spec_N)
3133 -- Restore all references of corresponding record types to the
3134 -- original concurrent types.
3136 Replace_Types (To_Corresponding => False);
3137 Priv_Spec := Find_Corresponding_Spec (N, False);
3139 -- The current body truly belongs to a primitive declared between
3140 -- a private and a full view. We leave the modified body as is,
3141 -- and return the true spec.
3143 if Present (Priv_Spec)
3144 and then Is_Private_Primitive (Priv_Spec)
3149 -- In case that this is some sort of error, restore the original
3150 -- state of the body.
3152 Replace_Types (To_Corresponding => True);
3156 end Disambiguate_Spec;
3158 ----------------------------
3159 -- Exchange_Limited_Views --
3160 ----------------------------
3162 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3163 Result : Elist_Id := No_Elist;
3165 procedure Detect_And_Exchange (Id : Entity_Id);
3166 -- Determine whether Id's type denotes an incomplete type associated
3167 -- with a limited with clause and exchange the limited view with the
3168 -- non-limited one when available. Note that the non-limited view
3169 -- may exist because of a with_clause in another unit in the context,
3170 -- but cannot be used because the current view of the enclosing unit
3171 -- is still a limited view.
3173 -------------------------
3174 -- Detect_And_Exchange --
3175 -------------------------
3177 procedure Detect_And_Exchange (Id : Entity_Id) is
3178 Typ : constant Entity_Id := Etype (Id);
3180 if From_Limited_With (Typ)
3181 and then Has_Non_Limited_View (Typ)
3182 and then not From_Limited_With (Scope (Typ))
3185 Result := New_Elmt_List;
3188 Prepend_Elmt (Typ, Result);
3189 Prepend_Elmt (Id, Result);
3190 Set_Etype (Id, Non_Limited_View (Typ));
3192 end Detect_And_Exchange;
3198 -- Start of processing for Exchange_Limited_Views
3201 -- Do not process subprogram bodies as they already use the non-
3202 -- limited view of types.
3204 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3208 -- Examine all formals and swap views when applicable
3210 Formal := First_Formal (Subp_Id);
3211 while Present (Formal) loop
3212 Detect_And_Exchange (Formal);
3214 Next_Formal (Formal);
3217 -- Process the return type of a function
3219 if Ekind (Subp_Id) = E_Function then
3220 Detect_And_Exchange (Subp_Id);
3224 end Exchange_Limited_Views;
3226 -------------------------------------
3227 -- Is_Private_Concurrent_Primitive --
3228 -------------------------------------
3230 function Is_Private_Concurrent_Primitive
3231 (Subp_Id : Entity_Id) return Boolean
3233 Formal_Typ : Entity_Id;
3236 if Present (First_Formal (Subp_Id)) then
3237 Formal_Typ := Etype (First_Formal (Subp_Id));
3239 if Is_Concurrent_Record_Type (Formal_Typ) then
3240 if Is_Class_Wide_Type (Formal_Typ) then
3241 Formal_Typ := Root_Type (Formal_Typ);
3244 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3247 -- The type of the first formal is a concurrent tagged type with
3251 Is_Concurrent_Type (Formal_Typ)
3252 and then Is_Tagged_Type (Formal_Typ)
3253 and then Has_Private_Declaration (Formal_Typ);
3257 end Is_Private_Concurrent_Primitive;
3259 -------------------------
3260 -- Mask_Unfrozen_Types --
3261 -------------------------
3263 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3264 Result : Elist_Id := No_Elist;
3266 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3267 -- Mask all types referenced in the subtree rooted at Node
3269 --------------------
3270 -- Mask_Type_Refs --
3271 --------------------
3273 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3274 procedure Mask_Type (Typ : Entity_Id);
3275 -- ??? what does this do?
3281 procedure Mask_Type (Typ : Entity_Id) is
3283 -- Skip Itypes created by the preanalysis
3286 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3291 if not Is_Frozen (Typ) then
3292 Set_Is_Frozen (Typ);
3293 Append_New_Elmt (Typ, Result);
3297 -- Start of processing for Mask_Type_Refs
3300 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3301 Mask_Type (Etype (Entity (Node)));
3303 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3304 Mask_Type (Scope (Entity (Node)));
3307 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3308 and then Present (Etype (Node))
3310 Mask_Type (Etype (Node));
3316 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3320 Return_Stmt : constant Node_Id :=
3321 First (Statements (Handled_Statement_Sequence (N)));
3323 -- Start of processing for Mask_Unfrozen_Types
3326 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3328 Mask_References (Expression (Return_Stmt));
3331 end Mask_Unfrozen_Types;
3333 ---------------------------
3334 -- Restore_Limited_Views --
3335 ---------------------------
3337 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3338 Elmt : Elmt_Id := First_Elmt (Restore_List);
3342 while Present (Elmt) loop
3345 Set_Etype (Id, Node (Elmt));
3348 end Restore_Limited_Views;
3350 ----------------------------
3351 -- Set_Trivial_Subprogram --
3352 ----------------------------
3354 procedure Set_Trivial_Subprogram (N : Node_Id) is
3355 Nxt : constant Node_Id := Next (N);
3358 Set_Is_Trivial_Subprogram (Body_Id);
3360 if Present (Spec_Id) then
3361 Set_Is_Trivial_Subprogram (Spec_Id);
3365 and then Nkind (Nxt) = N_Simple_Return_Statement
3366 and then No (Next (Nxt))
3367 and then Present (Expression (Nxt))
3368 and then Is_Entity_Name (Expression (Nxt))
3370 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3372 end Set_Trivial_Subprogram;
3374 ---------------------------
3375 -- Unmask_Unfrozen_Types --
3376 ---------------------------
3378 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3379 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3382 while Present (Elmt) loop
3383 Set_Is_Frozen (Node (Elmt), False);
3386 end Unmask_Unfrozen_Types;
3388 ---------------------------------
3389 -- Verify_Overriding_Indicator --
3390 ---------------------------------
3392 procedure Verify_Overriding_Indicator is
3394 if Must_Override (Body_Spec) then
3395 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3396 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3400 elsif not Present (Overridden_Operation (Spec_Id)) then
3402 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3404 -- Overriding indicators aren't allowed for protected subprogram
3405 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3406 -- this to a warning if -gnatd.E is enabled.
3408 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3409 Error_Msg_Warn := Error_To_Warning;
3411 ("<<overriding indicator not allowed for protected "
3412 & "subprogram body", Body_Spec);
3415 elsif Must_Not_Override (Body_Spec) then
3416 if Present (Overridden_Operation (Spec_Id)) then
3418 ("subprogram& overrides inherited operation",
3419 Body_Spec, Spec_Id);
3421 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3422 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3425 ("subprogram& overrides predefined operator ",
3426 Body_Spec, Spec_Id);
3428 -- Overriding indicators aren't allowed for protected subprogram
3429 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3430 -- this to a warning if -gnatd.E is enabled.
3432 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3433 Error_Msg_Warn := Error_To_Warning;
3436 ("<<overriding indicator not allowed "
3437 & "for protected subprogram body", Body_Spec);
3439 -- If this is not a primitive operation, then the overriding
3440 -- indicator is altogether illegal.
3442 elsif not Is_Primitive (Spec_Id) then
3444 ("overriding indicator only allowed "
3445 & "if subprogram is primitive", Body_Spec);
3448 -- If checking the style rule and the operation overrides, then
3449 -- issue a warning about a missing overriding_indicator. Protected
3450 -- subprogram bodies are excluded from this style checking, since
3451 -- they aren't primitives (even though their declarations can
3452 -- override) and aren't allowed to have an overriding_indicator.
3455 and then Present (Overridden_Operation (Spec_Id))
3456 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3458 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3459 Style.Missing_Overriding (N, Body_Id);
3462 and then Can_Override_Operator (Spec_Id)
3463 and then not In_Predefined_Unit (Spec_Id)
3465 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3466 Style.Missing_Overriding (N, Body_Id);
3468 end Verify_Overriding_Indicator;
3472 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3473 Saved_ISMP : constant Boolean :=
3474 Ignore_SPARK_Mode_Pragmas_In_Instance;
3475 -- Save the Ghost and SPARK mode-related data to restore on exit
3477 -- Start of processing for Analyze_Subprogram_Body_Helper
3480 -- A [generic] subprogram body freezes the contract of the nearest
3481 -- enclosing package body and all other contracts encountered in the
3482 -- same declarative part up to and excluding the subprogram body:
3484 -- package body Nearest_Enclosing_Package
3485 -- with Refined_State => (State => Constit)
3489 -- procedure Freezes_Enclosing_Package_Body
3490 -- with Refined_Depends => (Input => Constit) ...
3492 -- This ensures that any annotations referenced by the contract of the
3493 -- [generic] subprogram body are available. This form of freezing is
3494 -- decoupled from the usual Freeze_xxx mechanism because it must also
3495 -- work in the context of generics where normal freezing is disabled.
3497 -- Only bodies coming from source should cause this type of freezing.
3498 -- Expression functions that act as bodies and complete an initial
3499 -- declaration must be included in this category, hence the use of
3502 if Comes_From_Source (Original_Node (N)) then
3503 Freeze_Previous_Contracts (N);
3506 -- Generic subprograms are handled separately. They always have a
3507 -- generic specification. Determine whether current scope has a
3508 -- previous declaration.
3510 -- If the subprogram body is defined within an instance of the same
3511 -- name, the instance appears as a package renaming, and will be hidden
3512 -- within the subprogram.
3514 if Present (Prev_Id)
3515 and then not Is_Overloadable (Prev_Id)
3516 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3517 or else Comes_From_Source (Prev_Id))
3519 if Is_Generic_Subprogram (Prev_Id) then
3522 -- A subprogram body is Ghost when it is stand alone and subject
3523 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3524 -- the mode now to ensure that any nodes generated during analysis
3525 -- and expansion are properly marked as Ghost.
3527 Mark_And_Set_Ghost_Body (N, Spec_Id);
3529 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3530 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3532 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3534 if Nkind (N) = N_Subprogram_Body then
3535 HSS := Handled_Statement_Sequence (N);
3536 Check_Missing_Return;
3541 -- Otherwise a previous entity conflicts with the subprogram name.
3542 -- Attempting to enter name will post error.
3545 Enter_Name (Body_Id);
3549 -- Non-generic case, find the subprogram declaration, if one was seen,
3550 -- or enter new overloaded entity in the current scope. If the
3551 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3552 -- part of the context of one of its subunits. No need to redo the
3555 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3559 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3561 if Nkind (N) = N_Subprogram_Body_Stub
3562 or else No (Corresponding_Spec (N))
3564 if Is_Private_Concurrent_Primitive (Body_Id) then
3565 Spec_Id := Disambiguate_Spec;
3567 -- A subprogram body is Ghost when it is stand alone and
3568 -- subject to pragma Ghost or when the corresponding spec is
3569 -- Ghost. Set the mode now to ensure that any nodes generated
3570 -- during analysis and expansion are properly marked as Ghost.
3572 Mark_And_Set_Ghost_Body (N, Spec_Id);
3575 Spec_Id := Find_Corresponding_Spec (N);
3577 -- A subprogram body is Ghost when it is stand alone and
3578 -- subject to pragma Ghost or when the corresponding spec is
3579 -- Ghost. Set the mode now to ensure that any nodes generated
3580 -- during analysis and expansion are properly marked as Ghost.
3582 Mark_And_Set_Ghost_Body (N, Spec_Id);
3584 -- In GNATprove mode, if the body has no previous spec, create
3585 -- one so that the inlining machinery can operate properly.
3586 -- Transfer aspects, if any, to the new spec, so that they
3587 -- are legal and can be processed ahead of the body.
3588 -- We make two copies of the given spec, one for the new
3589 -- declaration, and one for the body.
3591 if No (Spec_Id) and then GNATprove_Mode
3593 -- Inlining does not apply during pre-analysis of code
3595 and then Full_Analysis
3597 -- Inlining only applies to full bodies, not stubs
3599 and then Nkind (N) /= N_Subprogram_Body_Stub
3601 -- Inlining only applies to bodies in the source code, not to
3602 -- those generated by the compiler. In particular, expression
3603 -- functions, whose body is generated by the compiler, are
3604 -- treated specially by GNATprove.
3606 and then Comes_From_Source (Body_Id)
3608 -- This cannot be done for a compilation unit, which is not
3609 -- in a context where we can insert a new spec.
3611 and then Is_List_Member (N)
3613 -- Inlining only applies to subprograms without contracts,
3614 -- as a contract is a sign that GNATprove should perform a
3615 -- modular analysis of the subprogram instead of a contextual
3616 -- analysis at each call site. The same test is performed in
3617 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3618 -- here in another form (because the contract has not been
3619 -- attached to the body) to avoid front-end errors in case
3620 -- pragmas are used instead of aspects, because the
3621 -- corresponding pragmas in the body would not be transferred
3622 -- to the spec, leading to legality errors.
3624 and then not Body_Has_Contract
3625 and then not Inside_A_Generic
3627 Build_Subprogram_Declaration;
3629 -- If this is a function that returns a constrained array, and
3630 -- we are generating SPARK_For_C, create subprogram declaration
3631 -- to simplify subsequent C generation.
3634 and then Modify_Tree_For_C
3635 and then Nkind (Body_Spec) = N_Function_Specification
3636 and then Is_Array_Type (Etype (Body_Id))
3637 and then Is_Constrained (Etype (Body_Id))
3639 Build_Subprogram_Declaration;
3643 -- If this is a duplicate body, no point in analyzing it
3645 if Error_Posted (N) then
3649 -- A subprogram body should cause freezing of its own declaration,
3650 -- but if there was no previous explicit declaration, then the
3651 -- subprogram will get frozen too late (there may be code within
3652 -- the body that depends on the subprogram having been frozen,
3653 -- such as uses of extra formals), so we force it to be frozen
3654 -- here. Same holds if the body and spec are compilation units.
3655 -- Finally, if the return type is an anonymous access to protected
3656 -- subprogram, it must be frozen before the body because its
3657 -- expansion has generated an equivalent type that is used when
3658 -- elaborating the body.
3660 -- An exception in the case of Ada 2012, AI05-177: The bodies
3661 -- created for expression functions do not freeze.
3664 and then Nkind (Original_Node (N)) /= N_Expression_Function
3666 Freeze_Before (N, Body_Id);
3668 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3669 Freeze_Before (N, Spec_Id);
3671 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3672 Freeze_Before (N, Etype (Body_Id));
3676 Spec_Id := Corresponding_Spec (N);
3678 -- A subprogram body is Ghost when it is stand alone and subject
3679 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3680 -- the mode now to ensure that any nodes generated during analysis
3681 -- and expansion are properly marked as Ghost.
3683 Mark_And_Set_Ghost_Body (N, Spec_Id);
3687 -- Previously we scanned the body to look for nested subprograms, and
3688 -- rejected an inline directive if nested subprograms were present,
3689 -- because the back-end would generate conflicting symbols for the
3690 -- nested bodies. This is now unnecessary.
3692 -- Look ahead to recognize a pragma Inline that appears after the body
3694 Check_Inline_Pragma (Spec_Id);
3696 -- Deal with special case of a fully private operation in the body of
3697 -- the protected type. We must create a declaration for the subprogram,
3698 -- in order to attach the protected subprogram that will be used in
3699 -- internal calls. We exclude compiler generated bodies from the
3700 -- expander since the issue does not arise for those cases.
3703 and then Comes_From_Source (N)
3704 and then Is_Protected_Type (Current_Scope)
3706 Spec_Id := Build_Private_Protected_Declaration (N);
3709 -- If we are generating C and this is a function returning a constrained
3710 -- array type for which we must create a procedure with an extra out
3711 -- parameter, build and analyze the body now. The procedure declaration
3712 -- has already been created. We reuse the source body of the function,
3713 -- because in an instance it may contain global references that cannot
3714 -- be reanalyzed. The source function itself is not used any further,
3715 -- so we mark it as having a completion. If the subprogram is a stub the
3716 -- transformation is done later, when the proper body is analyzed.
3719 and then Modify_Tree_For_C
3720 and then Present (Spec_Id)
3721 and then Ekind (Spec_Id) = E_Function
3722 and then Nkind (N) /= N_Subprogram_Body_Stub
3723 and then Rewritten_For_C (Spec_Id)
3725 Set_Has_Completion (Spec_Id);
3727 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3730 -- The entity for the created procedure must remain invisible, so it
3731 -- does not participate in resolution of subsequent references to the
3734 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3738 -- If a separate spec is present, then deal with freezing issues
3740 if Present (Spec_Id) then
3741 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3742 Verify_Overriding_Indicator;
3744 -- In general, the spec will be frozen when we start analyzing the
3745 -- body. However, for internally generated operations, such as
3746 -- wrapper functions for inherited operations with controlling
3747 -- results, the spec may not have been frozen by the time we expand
3748 -- the freeze actions that include the bodies. In particular, extra
3749 -- formals for accessibility or for return-in-place may need to be
3750 -- generated. Freeze nodes, if any, are inserted before the current
3751 -- body. These freeze actions are also needed in ASIS mode and in
3752 -- Compile_Only mode to enable the proper back-end type annotations.
3753 -- They are necessary in any case to insure order of elaboration
3756 if not Is_Frozen (Spec_Id)
3757 and then (Expander_Active
3759 or else (Operating_Mode = Check_Semantics
3760 and then Serious_Errors_Detected = 0))
3762 -- The body generated for an expression function that is not a
3763 -- completion is a freeze point neither for the profile nor for
3764 -- anything else. That's why, in order to prevent any freezing
3765 -- during analysis, we need to mask types declared outside the
3766 -- expression that are not yet frozen.
3768 if Nkind (N) = N_Subprogram_Body
3769 and then Was_Expression_Function (N)
3770 and then not Has_Completion (Spec_Id)
3772 Set_Is_Frozen (Spec_Id);
3773 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3775 Set_Has_Delayed_Freeze (Spec_Id);
3776 Freeze_Before (N, Spec_Id);
3781 -- If the subprogram has a class-wide clone, build its body as a copy
3782 -- of the original body, and rewrite body of original subprogram as a
3783 -- wrapper that calls the clone.
3785 if Present (Spec_Id)
3786 and then Present (Class_Wide_Clone (Spec_Id))
3787 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3789 Build_Class_Wide_Clone_Body (Spec_Id, N);
3791 -- This is the new body for the existing primitive operation
3793 Rewrite (N, Build_Class_Wide_Clone_Call
3794 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3795 Set_Has_Completion (Spec_Id, False);
3800 -- Place subprogram on scope stack, and make formals visible. If there
3801 -- is a spec, the visible entity remains that of the spec.
3803 if Present (Spec_Id) then
3804 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3806 if Is_Child_Unit (Spec_Id) then
3807 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3811 Style.Check_Identifier (Body_Id, Spec_Id);
3814 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3815 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3817 if Is_Abstract_Subprogram (Spec_Id) then
3818 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3822 Set_Convention (Body_Id, Convention (Spec_Id));
3823 Set_Has_Completion (Spec_Id);
3825 if Is_Protected_Type (Scope (Spec_Id)) then
3826 Prot_Typ := Scope (Spec_Id);
3829 -- If this is a body generated for a renaming, do not check for
3830 -- full conformance. The check is redundant, because the spec of
3831 -- the body is a copy of the spec in the renaming declaration,
3832 -- and the test can lead to spurious errors on nested defaults.
3834 if Present (Spec_Decl)
3835 and then not Comes_From_Source (N)
3837 (Nkind (Original_Node (Spec_Decl)) =
3838 N_Subprogram_Renaming_Declaration
3839 or else (Present (Corresponding_Body (Spec_Decl))
3841 Nkind (Unit_Declaration_Node
3842 (Corresponding_Body (Spec_Decl))) =
3843 N_Subprogram_Renaming_Declaration))
3847 -- Conversely, the spec may have been generated for specless body
3848 -- with an inline pragma. The entity comes from source, which is
3849 -- both semantically correct and necessary for proper inlining.
3850 -- The subprogram declaration itself is not in the source.
3852 elsif Comes_From_Source (N)
3853 and then Present (Spec_Decl)
3854 and then not Comes_From_Source (Spec_Decl)
3855 and then Has_Pragma_Inline (Spec_Id)
3862 Fully_Conformant, True, Conformant, Body_Id);
3865 -- If the body is not fully conformant, we have to decide if we
3866 -- should analyze it or not. If it has a really messed up profile
3867 -- then we probably should not analyze it, since we will get too
3868 -- many bogus messages.
3870 -- Our decision is to go ahead in the non-fully conformant case
3871 -- only if it is at least mode conformant with the spec. Note
3872 -- that the call to Check_Fully_Conformant has issued the proper
3873 -- error messages to complain about the lack of conformance.
3876 and then not Mode_Conformant (Body_Id, Spec_Id)
3882 if Spec_Id /= Body_Id then
3883 Reference_Body_Formals (Spec_Id, Body_Id);
3886 Set_Ekind (Body_Id, E_Subprogram_Body);
3888 if Nkind (N) = N_Subprogram_Body_Stub then
3889 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3894 Set_Corresponding_Spec (N, Spec_Id);
3896 -- Ada 2005 (AI-345): If the operation is a primitive operation
3897 -- of a concurrent type, the type of the first parameter has been
3898 -- replaced with the corresponding record, which is the proper
3899 -- run-time structure to use. However, within the body there may
3900 -- be uses of the formals that depend on primitive operations
3901 -- of the type (in particular calls in prefixed form) for which
3902 -- we need the original concurrent type. The operation may have
3903 -- several controlling formals, so the replacement must be done
3906 if Comes_From_Source (Spec_Id)
3907 and then Present (First_Entity (Spec_Id))
3908 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3909 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3910 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3911 and then Present (Corresponding_Concurrent_Type
3912 (Etype (First_Entity (Spec_Id))))
3915 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3919 Form := First_Formal (Spec_Id);
3920 while Present (Form) loop
3921 if Etype (Form) = Typ then
3922 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3930 -- Make the formals visible, and place subprogram on scope stack.
3931 -- This is also the point at which we set Last_Real_Spec_Entity
3932 -- to mark the entities which will not be moved to the body.
3934 Install_Formals (Spec_Id);
3935 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3937 -- Within an instance, add local renaming declarations so that
3938 -- gdb can retrieve the values of actuals more easily. This is
3939 -- only relevant if generating code (and indeed we definitely
3940 -- do not want these definitions -gnatc mode, because that would
3943 if Is_Generic_Instance (Spec_Id)
3944 and then Is_Wrapper_Package (Current_Scope)
3945 and then Expander_Active
3947 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3950 Push_Scope (Spec_Id);
3952 -- Make sure that the subprogram is immediately visible. For
3953 -- child units that have no separate spec this is indispensable.
3954 -- Otherwise it is safe albeit redundant.
3956 Set_Is_Immediately_Visible (Spec_Id);
3959 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3960 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3961 Set_Scope (Body_Id, Scope (Spec_Id));
3963 -- Case of subprogram body with no previous spec
3966 -- Check for style warning required
3970 -- Only apply check for source level subprograms for which checks
3971 -- have not been suppressed.
3973 and then Comes_From_Source (Body_Id)
3974 and then not Suppress_Style_Checks (Body_Id)
3976 -- No warnings within an instance
3978 and then not In_Instance
3980 -- No warnings for expression functions
3982 and then Nkind (Original_Node (N)) /= N_Expression_Function
3984 Style.Body_With_No_Spec (N);
3987 New_Overloaded_Entity (Body_Id);
3989 if Nkind (N) /= N_Subprogram_Body_Stub then
3990 Set_Acts_As_Spec (N);
3991 Generate_Definition (Body_Id);
3993 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3995 -- If the body is an entry wrapper created for an entry with
3996 -- preconditions, it must be compiled in the context of the
3997 -- enclosing synchronized object, because it may mention other
3998 -- operations of the type.
4000 if Is_Entry_Wrapper (Body_Id) then
4002 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4005 Install_Declarations (Prot);
4009 Install_Formals (Body_Id);
4011 Push_Scope (Body_Id);
4014 -- For stubs and bodies with no previous spec, generate references to
4017 Generate_Reference_To_Formals (Body_Id);
4020 -- Entry barrier functions are generated outside the protected type and
4021 -- should not carry the SPARK_Mode of the enclosing context.
4023 if Nkind (N) = N_Subprogram_Body
4024 and then Is_Entry_Barrier_Function (N)
4028 -- The body is generated as part of expression function expansion. When
4029 -- the expression function appears in the visible declarations of a
4030 -- package, the body is added to the private declarations. Since both
4031 -- declarative lists may be subject to a different SPARK_Mode, inherit
4032 -- the mode of the spec.
4034 -- package P with SPARK_Mode is
4035 -- function Expr_Func ... is (...); -- original
4036 -- [function Expr_Func ...;] -- generated spec
4039 -- pragma SPARK_Mode (Off);
4040 -- [function Expr_Func ... is return ...;] -- generated body
4041 -- end P; -- mode is ON
4043 elsif not Comes_From_Source (N)
4044 and then Present (Spec_Id)
4045 and then Is_Expression_Function (Spec_Id)
4047 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4048 Set_SPARK_Pragma_Inherited
4049 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4051 -- Set the SPARK_Mode from the current context (may be overwritten later
4052 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4053 -- initially on a stand-alone subprogram body, but is then relocated to
4054 -- a generated corresponding spec. In this scenario the mode is shared
4055 -- between the spec and body.
4057 elsif No (SPARK_Pragma (Body_Id)) then
4058 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4059 Set_SPARK_Pragma_Inherited (Body_Id);
4062 -- A subprogram body may be instantiated or inlined at a later pass.
4063 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4064 -- applied to the initial declaration of the body.
4066 if Present (Spec_Id) then
4067 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4068 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4072 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4073 -- case the body is instantiated or inlined later and out of context.
4074 -- The body uses this attribute to restore the value of the global
4077 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4078 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4080 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4081 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4085 -- If this is the proper body of a stub, we must verify that the stub
4086 -- conforms to the body, and to the previous spec if one was present.
4087 -- We know already that the body conforms to that spec. This test is
4088 -- only required for subprograms that come from source.
4090 if Nkind (Parent (N)) = N_Subunit
4091 and then Comes_From_Source (N)
4092 and then not Error_Posted (Body_Id)
4093 and then Nkind (Corresponding_Stub (Parent (N))) =
4094 N_Subprogram_Body_Stub
4097 Old_Id : constant Entity_Id :=
4099 (Specification (Corresponding_Stub (Parent (N))));
4101 Conformant : Boolean := False;
4104 if No (Spec_Id) then
4105 Check_Fully_Conformant (Body_Id, Old_Id);
4109 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4111 if not Conformant then
4113 -- The stub was taken to be a new declaration. Indicate that
4116 Set_Has_Completion (Old_Id, False);
4122 Set_Has_Completion (Body_Id);
4123 Check_Eliminated (Body_Id);
4125 -- Analyze any aspect specifications that appear on the subprogram body
4126 -- stub. Stop the analysis now as the stub does not have a declarative
4127 -- or a statement part, and it cannot be inlined.
4129 if Nkind (N) = N_Subprogram_Body_Stub then
4130 if Has_Aspects (N) then
4131 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4139 -- Note: Normally we don't do any inlining if expansion is off, since
4140 -- we won't generate code in any case. An exception arises in GNATprove
4141 -- mode where we want to expand some calls in place, even with expansion
4142 -- disabled, since the inlining eases formal verification.
4144 if not GNATprove_Mode
4145 and then Expander_Active
4146 and then Serious_Errors_Detected = 0
4147 and then Present (Spec_Id)
4148 and then Has_Pragma_Inline (Spec_Id)
4150 -- Legacy implementation (relying on front-end inlining)
4152 if not Back_End_Inlining then
4153 if (Has_Pragma_Inline_Always (Spec_Id)
4154 and then not Opt.Disable_FE_Inline_Always)
4155 or else (Front_End_Inlining
4156 and then not Opt.Disable_FE_Inline)
4158 Build_Body_To_Inline (N, Spec_Id);
4161 -- New implementation (relying on back-end inlining)
4164 if Has_Pragma_Inline_Always (Spec_Id)
4165 or else Optimization_Level > 0
4167 -- Handle function returning an unconstrained type
4169 if Comes_From_Source (Body_Id)
4170 and then Ekind (Spec_Id) = E_Function
4171 and then Returns_Unconstrained_Type (Spec_Id)
4173 -- If function builds in place, i.e. returns a limited type,
4174 -- inlining cannot be done.
4176 and then not Is_Limited_Type (Etype (Spec_Id))
4178 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4182 Subp_Body : constant Node_Id :=
4183 Unit_Declaration_Node (Body_Id);
4184 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4187 -- Do not pass inlining to the backend if the subprogram
4188 -- has declarations or statements which cannot be inlined
4189 -- by the backend. This check is done here to emit an
4190 -- error instead of the generic warning message reported
4191 -- by the GCC backend (ie. "function might not be
4194 if Present (Subp_Decl)
4195 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4199 elsif Has_Excluded_Statement
4202 (Handled_Statement_Sequence (Subp_Body)))
4206 -- If the backend inlining is available then at this
4207 -- stage we only have to mark the subprogram as inlined.
4208 -- The expander will take care of registering it in the
4209 -- table of subprograms inlined by the backend a part of
4210 -- processing calls to it (cf. Expand_Call)
4213 Set_Is_Inlined (Spec_Id);
4220 -- In GNATprove mode, inline only when there is a separate subprogram
4221 -- declaration for now, as inlining of subprogram bodies acting as
4222 -- declarations, or subprogram stubs, are not supported by front-end
4223 -- inlining. This inlining should occur after analysis of the body, so
4224 -- that it is known whether the value of SPARK_Mode, which can be
4225 -- defined by a pragma inside the body, is applicable to the body.
4226 -- Inlining can be disabled with switch -gnatdm
4228 elsif GNATprove_Mode
4229 and then Full_Analysis
4230 and then not Inside_A_Generic
4231 and then Present (Spec_Id)
4233 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4234 and then Body_Has_SPARK_Mode_On
4235 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4236 and then not Body_Has_Contract
4237 and then not Debug_Flag_M
4239 Build_Body_To_Inline (N, Spec_Id);
4242 -- When generating code, inherited pre/postconditions are handled when
4243 -- expanding the corresponding contract.
4245 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4246 -- of the specification we have to install the private withed units.
4247 -- This holds for child units as well.
4249 if Is_Compilation_Unit (Body_Id)
4250 or else Nkind (Parent (N)) = N_Compilation_Unit
4252 Install_Private_With_Clauses (Body_Id);
4255 Check_Anonymous_Return;
4257 -- Set the Protected_Formal field of each extra formal of the protected
4258 -- subprogram to reference the corresponding extra formal of the
4259 -- subprogram that implements it. For regular formals this occurs when
4260 -- the protected subprogram's declaration is expanded, but the extra
4261 -- formals don't get created until the subprogram is frozen. We need to
4262 -- do this before analyzing the protected subprogram's body so that any
4263 -- references to the original subprogram's extra formals will be changed
4264 -- refer to the implementing subprogram's formals (see Expand_Formal).
4266 if Present (Spec_Id)
4267 and then Is_Protected_Type (Scope (Spec_Id))
4268 and then Present (Protected_Body_Subprogram (Spec_Id))
4271 Impl_Subp : constant Entity_Id :=
4272 Protected_Body_Subprogram (Spec_Id);
4273 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4274 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4277 while Present (Prot_Ext_Formal) loop
4278 pragma Assert (Present (Impl_Ext_Formal));
4279 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4280 Next_Formal_With_Extras (Prot_Ext_Formal);
4281 Next_Formal_With_Extras (Impl_Ext_Formal);
4286 -- Now we can go on to analyze the body
4288 HSS := Handled_Statement_Sequence (N);
4289 Set_Actual_Subtypes (N, Current_Scope);
4291 -- Add a declaration for the Protection object, renaming declarations
4292 -- for discriminals and privals and finally a declaration for the entry
4293 -- family index (if applicable). This form of early expansion is done
4294 -- when the Expander is active because Install_Private_Data_Declarations
4295 -- references entities which were created during regular expansion. The
4296 -- subprogram entity must come from source, and not be an internally
4297 -- generated subprogram.
4300 and then Present (Prot_Typ)
4301 and then Present (Spec_Id)
4302 and then Comes_From_Source (Spec_Id)
4303 and then not Is_Eliminated (Spec_Id)
4305 Install_Private_Data_Declarations
4306 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4309 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4310 -- may now appear in parameter and result profiles. Since the analysis
4311 -- of a subprogram body may use the parameter and result profile of the
4312 -- spec, swap any limited views with their non-limited counterpart.
4314 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4315 Exch_Views := Exchange_Limited_Views (Spec_Id);
4318 -- If the return type is an anonymous access type whose designated type
4319 -- is the limited view of a class-wide type and the non-limited view is
4320 -- available, update the return type accordingly.
4322 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4328 Rtyp := Etype (Spec_Id);
4330 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4331 Etyp := Directly_Designated_Type (Rtyp);
4333 if Is_Class_Wide_Type (Etyp)
4334 and then From_Limited_With (Etyp)
4337 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4343 -- Analyze any aspect specifications that appear on the subprogram body
4345 if Has_Aspects (N) then
4346 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4349 Analyze_Declarations (Declarations (N));
4351 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4353 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4354 if Present (SPARK_Pragma (Spec_Id)) then
4355 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4357 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4359 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4360 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4361 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4363 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4366 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4370 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4371 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4372 Error_Msg_Sloc := Sloc (Spec_Id);
4374 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4378 -- A subprogram body freezes its own contract. Analyze the contract
4379 -- after the declarations of the body have been processed as pragmas
4380 -- are now chained on the contract of the subprogram body.
4382 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4384 -- Check completion, and analyze the statements
4387 Inspect_Deferred_Constant_Completion (Declarations (N));
4390 -- Deal with end of scope processing for the body
4392 Process_End_Label (HSS, 't', Current_Scope);
4393 Update_Use_Clause_Chain;
4396 -- If we are compiling an entry wrapper, remove the enclosing
4397 -- synchronized object from the stack.
4399 if Is_Entry_Wrapper (Body_Id) then
4403 Check_Subprogram_Order (N);
4404 Set_Analyzed (Body_Id);
4406 -- If we have a separate spec, then the analysis of the declarations
4407 -- caused the entities in the body to be chained to the spec id, but
4408 -- we want them chained to the body id. Only the formal parameters
4409 -- end up chained to the spec id in this case.
4411 if Present (Spec_Id) then
4413 -- We must conform to the categorization of our spec
4415 Validate_Categorization_Dependency (N, Spec_Id);
4417 -- And if this is a child unit, the parent units must conform
4419 if Is_Child_Unit (Spec_Id) then
4420 Validate_Categorization_Dependency
4421 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4424 -- Here is where we move entities from the spec to the body
4426 -- Case where there are entities that stay with the spec
4428 if Present (Last_Real_Spec_Entity) then
4430 -- No body entities (happens when the only real spec entities come
4431 -- from precondition and postcondition pragmas).
4433 if No (Last_Entity (Body_Id)) then
4434 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4436 -- Body entities present (formals), so chain stuff past them
4440 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4443 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4444 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4445 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4447 -- Case where there are no spec entities, in this case there can be
4448 -- no body entities either, so just move everything.
4450 -- If the body is generated for an expression function, it may have
4451 -- been preanalyzed already, if 'access was applied to it.
4454 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4455 N_Expression_Function
4457 pragma Assert (No (Last_Entity (Body_Id)));
4461 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4462 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4463 Set_First_Entity (Spec_Id, Empty);
4464 Set_Last_Entity (Spec_Id, Empty);
4468 Check_Missing_Return;
4470 -- Now we are going to check for variables that are never modified in
4471 -- the body of the procedure. But first we deal with a special case
4472 -- where we want to modify this check. If the body of the subprogram
4473 -- starts with a raise statement or its equivalent, or if the body
4474 -- consists entirely of a null statement, then it is pretty obvious that
4475 -- it is OK to not reference the parameters. For example, this might be
4476 -- the following common idiom for a stubbed function: statement of the
4477 -- procedure raises an exception. In particular this deals with the
4478 -- common idiom of a stubbed function, which appears something like:
4480 -- function F (A : Integer) return Some_Type;
4483 -- raise Program_Error;
4487 -- Here the purpose of X is simply to satisfy the annoying requirement
4488 -- in Ada that there be at least one return, and we certainly do not
4489 -- want to go posting warnings on X that it is not initialized. On
4490 -- the other hand, if X is entirely unreferenced that should still
4493 -- What we do is to detect these cases, and if we find them, flag the
4494 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4495 -- suppress unwanted warnings. For the case of the function stub above
4496 -- we have a special test to set X as apparently assigned to suppress
4503 -- Skip call markers installed by the ABE mechanism, labels, and
4504 -- Push_xxx_Error_Label to find the first real statement.
4506 Stm := First (Statements (HSS));
4507 while Nkind_In (Stm, N_Call_Marker, N_Label)
4508 or else Nkind (Stm) in N_Push_xxx_Label
4513 -- Do the test on the original statement before expansion
4516 Ostm : constant Node_Id := Original_Node (Stm);
4519 -- If explicit raise statement, turn on flag
4521 if Nkind (Ostm) = N_Raise_Statement then
4522 Set_Trivial_Subprogram (Stm);
4524 -- If null statement, and no following statements, turn on flag
4526 elsif Nkind (Stm) = N_Null_Statement
4527 and then Comes_From_Source (Stm)
4528 and then No (Next (Stm))
4530 Set_Trivial_Subprogram (Stm);
4532 -- Check for explicit call cases which likely raise an exception
4534 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4535 if Is_Entity_Name (Name (Ostm)) then
4537 Ent : constant Entity_Id := Entity (Name (Ostm));
4540 -- If the procedure is marked No_Return, then likely it
4541 -- raises an exception, but in any case it is not coming
4542 -- back here, so turn on the flag.
4545 and then Ekind (Ent) = E_Procedure
4546 and then No_Return (Ent)
4548 Set_Trivial_Subprogram (Stm);
4556 -- Check for variables that are never modified
4563 -- If there is a separate spec, then transfer Never_Set_In_Source
4564 -- flags from out parameters to the corresponding entities in the
4565 -- body. The reason we do that is we want to post error flags on
4566 -- the body entities, not the spec entities.
4568 if Present (Spec_Id) then
4569 E1 := First_Entity (Spec_Id);
4570 while Present (E1) loop
4571 if Ekind (E1) = E_Out_Parameter then
4572 E2 := First_Entity (Body_Id);
4573 while Present (E2) loop
4574 exit when Chars (E1) = Chars (E2);
4578 if Present (E2) then
4579 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4587 -- Check references in body
4589 Check_References (Body_Id);
4592 -- Check for nested subprogram, and mark outer level subprogram if so
4598 if Present (Spec_Id) then
4605 Ent := Enclosing_Subprogram (Ent);
4606 exit when No (Ent) or else Is_Subprogram (Ent);
4609 if Present (Ent) then
4610 Set_Has_Nested_Subprogram (Ent);
4614 -- Restore the limited views in the spec, if any, to let the back end
4615 -- process it without running into circularities.
4617 if Exch_Views /= No_Elist then
4618 Restore_Limited_Views (Exch_Views);
4621 if Mask_Types /= No_Elist then
4622 Unmask_Unfrozen_Types (Mask_Types);
4625 if Present (Desig_View) then
4626 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4630 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4631 Restore_Ghost_Mode (Saved_GM);
4632 end Analyze_Subprogram_Body_Helper;
4634 ------------------------------------
4635 -- Analyze_Subprogram_Declaration --
4636 ------------------------------------
4638 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4639 Scop : constant Entity_Id := Current_Scope;
4640 Designator : Entity_Id;
4642 Is_Completion : Boolean;
4643 -- Indicates whether a null procedure declaration is a completion
4646 -- Null procedures are not allowed in SPARK
4648 if Nkind (Specification (N)) = N_Procedure_Specification
4649 and then Null_Present (Specification (N))
4651 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4653 -- Null procedures are allowed in protected types, following the
4654 -- recent AI12-0147.
4656 if Is_Protected_Type (Current_Scope)
4657 and then Ada_Version < Ada_2012
4659 Error_Msg_N ("protected operation cannot be a null procedure", N);
4662 Analyze_Null_Procedure (N, Is_Completion);
4664 -- The null procedure acts as a body, nothing further is needed
4666 if Is_Completion then
4671 Designator := Analyze_Subprogram_Specification (Specification (N));
4673 -- A reference may already have been generated for the unit name, in
4674 -- which case the following call is redundant. However it is needed for
4675 -- declarations that are the rewriting of an expression function.
4677 Generate_Definition (Designator);
4679 -- Set the SPARK mode from the current context (may be overwritten later
4680 -- with explicit pragma). This is not done for entry barrier functions
4681 -- because they are generated outside the protected type and should not
4682 -- carry the mode of the enclosing context.
4684 if Nkind (N) = N_Subprogram_Declaration
4685 and then Is_Entry_Barrier_Function (N)
4690 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4691 Set_SPARK_Pragma_Inherited (Designator);
4694 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4695 -- the body of this subprogram is instantiated or inlined later and out
4696 -- of context. The body uses this attribute to restore the value of the
4699 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4700 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4703 -- Preserve relevant elaboration-related attributes of the context which
4704 -- are no longer available or very expensive to recompute once analysis,
4705 -- resolution, and expansion are over.
4707 Mark_Elaboration_Attributes
4708 (N_Id => Designator,
4711 if Debug_Flag_C then
4712 Write_Str ("==> subprogram spec ");
4713 Write_Name (Chars (Designator));
4714 Write_Str (" from ");
4715 Write_Location (Sloc (N));
4720 Validate_RCI_Subprogram_Declaration (N);
4721 New_Overloaded_Entity (Designator);
4722 Check_Delayed_Subprogram (Designator);
4724 -- If the type of the first formal of the current subprogram is a non-
4725 -- generic tagged private type, mark the subprogram as being a private
4726 -- primitive. Ditto if this is a function with controlling result, and
4727 -- the return type is currently private. In both cases, the type of the
4728 -- controlling argument or result must be in the current scope for the
4729 -- operation to be primitive.
4731 if Has_Controlling_Result (Designator)
4732 and then Is_Private_Type (Etype (Designator))
4733 and then Scope (Etype (Designator)) = Current_Scope
4734 and then not Is_Generic_Actual_Type (Etype (Designator))
4736 Set_Is_Private_Primitive (Designator);
4738 elsif Present (First_Formal (Designator)) then
4740 Formal_Typ : constant Entity_Id :=
4741 Etype (First_Formal (Designator));
4743 Set_Is_Private_Primitive (Designator,
4744 Is_Tagged_Type (Formal_Typ)
4745 and then Scope (Formal_Typ) = Current_Scope
4746 and then Is_Private_Type (Formal_Typ)
4747 and then not Is_Generic_Actual_Type (Formal_Typ));
4751 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4754 if Ada_Version >= Ada_2005
4755 and then Comes_From_Source (N)
4756 and then Is_Dispatching_Operation (Designator)
4763 if Has_Controlling_Result (Designator) then
4764 Etyp := Etype (Designator);
4767 E := First_Entity (Designator);
4769 and then Is_Formal (E)
4770 and then not Is_Controlling_Formal (E)
4778 if Is_Access_Type (Etyp) then
4779 Etyp := Directly_Designated_Type (Etyp);
4782 if Is_Interface (Etyp)
4783 and then not Is_Abstract_Subprogram (Designator)
4784 and then not (Ekind (Designator) = E_Procedure
4785 and then Null_Present (Specification (N)))
4787 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4789 -- Specialize error message based on procedures vs. functions,
4790 -- since functions can't be null subprograms.
4792 if Ekind (Designator) = E_Procedure then
4794 ("interface procedure % must be abstract or null", N);
4797 ("interface function % must be abstract", N);
4803 -- What is the following code for, it used to be
4805 -- ??? Set_Suppress_Elaboration_Checks
4806 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4808 -- The following seems equivalent, but a bit dubious
4810 if Elaboration_Checks_Suppressed (Designator) then
4811 Set_Kill_Elaboration_Checks (Designator);
4814 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4815 Set_Categorization_From_Scope (Designator, Scop);
4818 -- For a compilation unit, check for library-unit pragmas
4820 Push_Scope (Designator);
4821 Set_Categorization_From_Pragmas (N);
4822 Validate_Categorization_Dependency (N, Designator);
4826 -- For a compilation unit, set body required. This flag will only be
4827 -- reset if a valid Import or Interface pragma is processed later on.
4829 if Nkind (Parent (N)) = N_Compilation_Unit then
4830 Set_Body_Required (Parent (N), True);
4832 if Ada_Version >= Ada_2005
4833 and then Nkind (Specification (N)) = N_Procedure_Specification
4834 and then Null_Present (Specification (N))
4837 ("null procedure cannot be declared at library level", N);
4841 Generate_Reference_To_Formals (Designator);
4842 Check_Eliminated (Designator);
4844 if Debug_Flag_C then
4846 Write_Str ("<== subprogram spec ");
4847 Write_Name (Chars (Designator));
4848 Write_Str (" from ");
4849 Write_Location (Sloc (N));
4853 if Is_Protected_Type (Current_Scope) then
4855 -- Indicate that this is a protected operation, because it may be
4856 -- used in subsequent declarations within the protected type.
4858 Set_Convention (Designator, Convention_Protected);
4861 List_Inherited_Pre_Post_Aspects (Designator);
4863 if Has_Aspects (N) then
4864 Analyze_Aspect_Specifications (N, Designator);
4866 end Analyze_Subprogram_Declaration;
4868 --------------------------------------
4869 -- Analyze_Subprogram_Specification --
4870 --------------------------------------
4872 -- Reminder: N here really is a subprogram specification (not a subprogram
4873 -- declaration). This procedure is called to analyze the specification in
4874 -- both subprogram bodies and subprogram declarations (specs).
4876 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4877 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4878 -- Determine whether entity E denotes the spec or body of an invariant
4881 ------------------------------------
4882 -- Is_Invariant_Procedure_Or_Body --
4883 ------------------------------------
4885 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4886 Decl : constant Node_Id := Unit_Declaration_Node (E);
4890 if Nkind (Decl) = N_Subprogram_Body then
4891 Spec := Corresponding_Spec (Decl);
4898 and then Ekind (Spec) = E_Procedure
4899 and then (Is_Partial_Invariant_Procedure (Spec)
4900 or else Is_Invariant_Procedure (Spec));
4901 end Is_Invariant_Procedure_Or_Body;
4905 Designator : constant Entity_Id := Defining_Entity (N);
4906 Formals : constant List_Id := Parameter_Specifications (N);
4908 -- Start of processing for Analyze_Subprogram_Specification
4911 -- User-defined operator is not allowed in SPARK, except as a renaming
4913 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4914 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4916 Check_SPARK_05_Restriction
4917 ("user-defined operator is not allowed", N);
4920 -- Proceed with analysis. Do not emit a cross-reference entry if the
4921 -- specification comes from an expression function, because it may be
4922 -- the completion of a previous declaration. If it is not, the cross-
4923 -- reference entry will be emitted for the new subprogram declaration.
4925 if Nkind (Parent (N)) /= N_Expression_Function then
4926 Generate_Definition (Designator);
4929 if Nkind (N) = N_Function_Specification then
4930 Set_Ekind (Designator, E_Function);
4931 Set_Mechanism (Designator, Default_Mechanism);
4933 Set_Ekind (Designator, E_Procedure);
4934 Set_Etype (Designator, Standard_Void_Type);
4937 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4938 -- those subprograms which could be inlined in GNATprove mode (because
4939 -- Body_To_Inline is non-Empty) but should not be inlined.
4941 if GNATprove_Mode then
4942 Set_Is_Inlined_Always (Designator);
4945 -- Introduce new scope for analysis of the formals and the return type
4947 Set_Scope (Designator, Current_Scope);
4949 if Present (Formals) then
4950 Push_Scope (Designator);
4951 Process_Formals (Formals, N);
4953 -- Check dimensions in N for formals with default expression
4955 Analyze_Dimension_Formals (N, Formals);
4957 -- Ada 2005 (AI-345): If this is an overriding operation of an
4958 -- inherited interface operation, and the controlling type is
4959 -- a synchronized type, replace the type with its corresponding
4960 -- record, to match the proper signature of an overriding operation.
4961 -- Same processing for an access parameter whose designated type is
4962 -- derived from a synchronized interface.
4964 -- This modification is not done for invariant procedures because
4965 -- the corresponding record may not necessarely be visible when the
4966 -- concurrent type acts as the full view of a private type.
4969 -- type Prot is private with Type_Invariant => ...;
4970 -- procedure ConcInvariant (Obj : Prot);
4972 -- protected type Prot is ...;
4973 -- type Concurrent_Record_Prot is record ...;
4974 -- procedure ConcInvariant (Obj : Prot) is
4976 -- end ConcInvariant;
4979 -- In the example above, both the spec and body of the invariant
4980 -- procedure must utilize the private type as the controlling type.
4982 if Ada_Version >= Ada_2005
4983 and then not Is_Invariant_Procedure_Or_Body (Designator)
4987 Formal_Typ : Entity_Id;
4988 Rec_Typ : Entity_Id;
4989 Desig_Typ : Entity_Id;
4992 Formal := First_Formal (Designator);
4993 while Present (Formal) loop
4994 Formal_Typ := Etype (Formal);
4996 if Is_Concurrent_Type (Formal_Typ)
4997 and then Present (Corresponding_Record_Type (Formal_Typ))
4999 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5001 if Present (Interfaces (Rec_Typ)) then
5002 Set_Etype (Formal, Rec_Typ);
5005 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5006 Desig_Typ := Designated_Type (Formal_Typ);
5008 if Is_Concurrent_Type (Desig_Typ)
5009 and then Present (Corresponding_Record_Type (Desig_Typ))
5011 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5013 if Present (Interfaces (Rec_Typ)) then
5014 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5019 Next_Formal (Formal);
5026 -- The subprogram scope is pushed and popped around the processing of
5027 -- the return type for consistency with call above to Process_Formals
5028 -- (which itself can call Analyze_Return_Type), and to ensure that any
5029 -- itype created for the return type will be associated with the proper
5032 elsif Nkind (N) = N_Function_Specification then
5033 Push_Scope (Designator);
5034 Analyze_Return_Type (N);
5040 if Nkind (N) = N_Function_Specification then
5042 -- Deal with operator symbol case
5044 if Nkind (Designator) = N_Defining_Operator_Symbol then
5045 Valid_Operator_Definition (Designator);
5048 May_Need_Actuals (Designator);
5050 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5051 -- the subprogram is abstract also. This does not apply to renaming
5052 -- declarations, where abstractness is inherited, and to subprogram
5053 -- bodies generated for stream operations, which become renamings as
5056 -- In case of primitives associated with abstract interface types
5057 -- the check is applied later (see Analyze_Subprogram_Declaration).
5059 if not Nkind_In (Original_Node (Parent (N)),
5060 N_Abstract_Subprogram_Declaration,
5061 N_Formal_Abstract_Subprogram_Declaration,
5062 N_Subprogram_Renaming_Declaration)
5064 if Is_Abstract_Type (Etype (Designator))
5065 and then not Is_Interface (Etype (Designator))
5068 ("function that returns abstract type must be abstract", N);
5070 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5071 -- access result whose designated type is abstract.
5073 elsif Ada_Version >= Ada_2012
5074 and then Nkind (Result_Definition (N)) = N_Access_Definition
5076 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5077 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5080 ("function whose access result designates abstract type "
5081 & "must be abstract", N);
5087 end Analyze_Subprogram_Specification;
5089 -----------------------
5090 -- Check_Conformance --
5091 -----------------------
5093 procedure Check_Conformance
5094 (New_Id : Entity_Id;
5096 Ctype : Conformance_Type;
5098 Conforms : out Boolean;
5099 Err_Loc : Node_Id := Empty;
5100 Get_Inst : Boolean := False;
5101 Skip_Controlling_Formals : Boolean := False)
5103 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5104 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5105 -- If Errmsg is True, then processing continues to post an error message
5106 -- for conformance error on given node. Two messages are output. The
5107 -- first message points to the previous declaration with a general "no
5108 -- conformance" message. The second is the detailed reason, supplied as
5109 -- Msg. The parameter N provide information for a possible & insertion
5110 -- in the message, and also provides the location for posting the
5111 -- message in the absence of a specified Err_Loc location.
5113 function Conventions_Match
5115 Id2 : Entity_Id) return Boolean;
5116 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5119 -----------------------
5120 -- Conformance_Error --
5121 -----------------------
5123 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5130 if No (Err_Loc) then
5136 Error_Msg_Sloc := Sloc (Old_Id);
5139 when Type_Conformant =>
5140 Error_Msg_N -- CODEFIX
5141 ("not type conformant with declaration#!", Enode);
5143 when Mode_Conformant =>
5144 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5146 ("not mode conformant with operation inherited#!",
5150 ("not mode conformant with declaration#!", Enode);
5153 when Subtype_Conformant =>
5154 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5156 ("not subtype conformant with operation inherited#!",
5160 ("not subtype conformant with declaration#!", Enode);
5163 when Fully_Conformant =>
5164 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5165 Error_Msg_N -- CODEFIX
5166 ("not fully conformant with operation inherited#!",
5169 Error_Msg_N -- CODEFIX
5170 ("not fully conformant with declaration#!", Enode);
5174 Error_Msg_NE (Msg, Enode, N);
5176 end Conformance_Error;
5178 -----------------------
5179 -- Conventions_Match --
5180 -----------------------
5182 function Conventions_Match
5184 Id2 : Entity_Id) return Boolean
5187 -- Ignore the conventions of anonymous access-to-subprogram types
5188 -- and subprogram types because these are internally generated and
5189 -- the only way these may receive a convention is if they inherit
5190 -- the convention of a related subprogram.
5192 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5195 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5200 -- Otherwise compare the conventions directly
5203 return Convention (Id1) = Convention (Id2);
5205 end Conventions_Match;
5209 Old_Type : constant Entity_Id := Etype (Old_Id);
5210 New_Type : constant Entity_Id := Etype (New_Id);
5211 Old_Formal : Entity_Id;
5212 New_Formal : Entity_Id;
5213 Access_Types_Match : Boolean;
5214 Old_Formal_Base : Entity_Id;
5215 New_Formal_Base : Entity_Id;
5217 -- Start of processing for Check_Conformance
5222 -- We need a special case for operators, since they don't appear
5225 if Ctype = Type_Conformant then
5226 if Ekind (New_Id) = E_Operator
5227 and then Operator_Matches_Spec (New_Id, Old_Id)
5233 -- If both are functions/operators, check return types conform
5235 if Old_Type /= Standard_Void_Type
5237 New_Type /= Standard_Void_Type
5239 -- If we are checking interface conformance we omit controlling
5240 -- arguments and result, because we are only checking the conformance
5241 -- of the remaining parameters.
5243 if Has_Controlling_Result (Old_Id)
5244 and then Has_Controlling_Result (New_Id)
5245 and then Skip_Controlling_Formals
5249 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5250 if Ctype >= Subtype_Conformant
5251 and then not Predicates_Match (Old_Type, New_Type)
5254 ("\predicate of return type does not match!", New_Id);
5257 ("\return type does not match!", New_Id);
5263 -- Ada 2005 (AI-231): In case of anonymous access types check the
5264 -- null-exclusion and access-to-constant attributes match.
5266 if Ada_Version >= Ada_2005
5267 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5269 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5270 or else Is_Access_Constant (Etype (Old_Type)) /=
5271 Is_Access_Constant (Etype (New_Type)))
5273 Conformance_Error ("\return type does not match!", New_Id);
5277 -- If either is a function/operator and the other isn't, error
5279 elsif Old_Type /= Standard_Void_Type
5280 or else New_Type /= Standard_Void_Type
5282 Conformance_Error ("\functions can only match functions!", New_Id);
5286 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5287 -- If this is a renaming as body, refine error message to indicate that
5288 -- the conflict is with the original declaration. If the entity is not
5289 -- frozen, the conventions don't have to match, the one of the renamed
5290 -- entity is inherited.
5292 if Ctype >= Subtype_Conformant then
5293 if not Conventions_Match (Old_Id, New_Id) then
5294 if not Is_Frozen (New_Id) then
5297 elsif Present (Err_Loc)
5298 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5299 and then Present (Corresponding_Spec (Err_Loc))
5301 Error_Msg_Name_1 := Chars (New_Id);
5303 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5304 Conformance_Error ("\prior declaration for% has convention %!");
5307 Conformance_Error ("\calling conventions do not match!");
5312 elsif Is_Formal_Subprogram (Old_Id)
5313 or else Is_Formal_Subprogram (New_Id)
5315 Conformance_Error ("\formal subprograms not allowed!");
5320 -- Deal with parameters
5322 -- Note: we use the entity information, rather than going directly
5323 -- to the specification in the tree. This is not only simpler, but
5324 -- absolutely necessary for some cases of conformance tests between
5325 -- operators, where the declaration tree simply does not exist.
5327 Old_Formal := First_Formal (Old_Id);
5328 New_Formal := First_Formal (New_Id);
5329 while Present (Old_Formal) and then Present (New_Formal) loop
5330 if Is_Controlling_Formal (Old_Formal)
5331 and then Is_Controlling_Formal (New_Formal)
5332 and then Skip_Controlling_Formals
5334 -- The controlling formals will have different types when
5335 -- comparing an interface operation with its match, but both
5336 -- or neither must be access parameters.
5338 if Is_Access_Type (Etype (Old_Formal))
5340 Is_Access_Type (Etype (New_Formal))
5342 goto Skip_Controlling_Formal;
5345 ("\access parameter does not match!", New_Formal);
5349 -- Ada 2012: Mode conformance also requires that formal parameters
5350 -- be both aliased, or neither.
5352 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5353 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5355 ("\aliased parameter mismatch!", New_Formal);
5359 if Ctype = Fully_Conformant then
5361 -- Names must match. Error message is more accurate if we do
5362 -- this before checking that the types of the formals match.
5364 if Chars (Old_Formal) /= Chars (New_Formal) then
5365 Conformance_Error ("\name& does not match!", New_Formal);
5367 -- Set error posted flag on new formal as well to stop
5368 -- junk cascaded messages in some cases.
5370 Set_Error_Posted (New_Formal);
5374 -- Null exclusion must match
5376 if Null_Exclusion_Present (Parent (Old_Formal))
5378 Null_Exclusion_Present (Parent (New_Formal))
5380 -- Only give error if both come from source. This should be
5381 -- investigated some time, since it should not be needed ???
5383 if Comes_From_Source (Old_Formal)
5385 Comes_From_Source (New_Formal)
5388 ("\null exclusion for& does not match", New_Formal);
5390 -- Mark error posted on the new formal to avoid duplicated
5391 -- complaint about types not matching.
5393 Set_Error_Posted (New_Formal);
5398 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5399 -- case occurs whenever a subprogram is being renamed and one of its
5400 -- parameters imposes a null exclusion. For example:
5402 -- type T is null record;
5403 -- type Acc_T is access T;
5404 -- subtype Acc_T_Sub is Acc_T;
5406 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5407 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5410 Old_Formal_Base := Etype (Old_Formal);
5411 New_Formal_Base := Etype (New_Formal);
5414 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5415 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5418 Access_Types_Match := Ada_Version >= Ada_2005
5420 -- Ensure that this rule is only applied when New_Id is a
5421 -- renaming of Old_Id.
5423 and then Nkind (Parent (Parent (New_Id))) =
5424 N_Subprogram_Renaming_Declaration
5425 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5426 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5427 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5429 -- Now handle the allowed access-type case
5431 and then Is_Access_Type (Old_Formal_Base)
5432 and then Is_Access_Type (New_Formal_Base)
5434 -- The type kinds must match. The only exception occurs with
5435 -- multiple generics of the form:
5438 -- type F is private; type A is private;
5439 -- type F_Ptr is access F; type A_Ptr is access A;
5440 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5441 -- package F_Pack is ... package A_Pack is
5442 -- package F_Inst is
5443 -- new F_Pack (A, A_Ptr, A_P);
5445 -- When checking for conformance between the parameters of A_P
5446 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5447 -- because the compiler has transformed A_Ptr into a subtype of
5448 -- F_Ptr. We catch this case in the code below.
5450 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5452 (Is_Generic_Type (Old_Formal_Base)
5453 and then Is_Generic_Type (New_Formal_Base)
5454 and then Is_Internal (New_Formal_Base)
5455 and then Etype (Etype (New_Formal_Base)) =
5457 and then Directly_Designated_Type (Old_Formal_Base) =
5458 Directly_Designated_Type (New_Formal_Base)
5459 and then ((Is_Itype (Old_Formal_Base)
5460 and then Can_Never_Be_Null (Old_Formal_Base))
5462 (Is_Itype (New_Formal_Base)
5463 and then Can_Never_Be_Null (New_Formal_Base)));
5465 -- Types must always match. In the visible part of an instance,
5466 -- usual overloading rules for dispatching operations apply, and
5467 -- we check base types (not the actual subtypes).
5469 if In_Instance_Visible_Part
5470 and then Is_Dispatching_Operation (New_Id)
5472 if not Conforming_Types
5473 (T1 => Base_Type (Etype (Old_Formal)),
5474 T2 => Base_Type (Etype (New_Formal)),
5476 Get_Inst => Get_Inst)
5477 and then not Access_Types_Match
5479 Conformance_Error ("\type of & does not match!", New_Formal);
5483 elsif not Conforming_Types
5484 (T1 => Old_Formal_Base,
5485 T2 => New_Formal_Base,
5487 Get_Inst => Get_Inst)
5488 and then not Access_Types_Match
5490 -- Don't give error message if old type is Any_Type. This test
5491 -- avoids some cascaded errors, e.g. in case of a bad spec.
5493 if Errmsg and then Old_Formal_Base = Any_Type then
5496 if Ctype >= Subtype_Conformant
5498 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5501 ("\predicate of & does not match!", New_Formal);
5504 ("\type of & does not match!", New_Formal);
5506 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5508 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5516 -- For mode conformance, mode must match
5518 if Ctype >= Mode_Conformant then
5519 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5520 if not Ekind_In (New_Id, E_Function, E_Procedure)
5521 or else not Is_Primitive_Wrapper (New_Id)
5523 Conformance_Error ("\mode of & does not match!", New_Formal);
5527 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5529 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5531 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5534 ("\mode of & does not match!", New_Formal);
5541 -- Part of mode conformance for access types is having the same
5542 -- constant modifier.
5544 elsif Access_Types_Match
5545 and then Is_Access_Constant (Old_Formal_Base) /=
5546 Is_Access_Constant (New_Formal_Base)
5549 ("\constant modifier does not match!", New_Formal);
5554 if Ctype >= Subtype_Conformant then
5556 -- Ada 2005 (AI-231): In case of anonymous access types check
5557 -- the null-exclusion and access-to-constant attributes must
5558 -- match. For null exclusion, we test the types rather than the
5559 -- formals themselves, since the attribute is only set reliably
5560 -- on the formals in the Ada 95 case, and we exclude the case
5561 -- where Old_Formal is marked as controlling, to avoid errors
5562 -- when matching completing bodies with dispatching declarations
5563 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5565 if Ada_Version >= Ada_2005
5566 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5567 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5569 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5570 Can_Never_Be_Null (Etype (New_Formal))
5572 not Is_Controlling_Formal (Old_Formal))
5574 Is_Access_Constant (Etype (Old_Formal)) /=
5575 Is_Access_Constant (Etype (New_Formal)))
5577 -- Do not complain if error already posted on New_Formal. This
5578 -- avoids some redundant error messages.
5580 and then not Error_Posted (New_Formal)
5582 -- It is allowed to omit the null-exclusion in case of stream
5583 -- attribute subprograms. We recognize stream subprograms
5584 -- through their TSS-generated suffix.
5587 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5590 if TSS_Name /= TSS_Stream_Read
5591 and then TSS_Name /= TSS_Stream_Write
5592 and then TSS_Name /= TSS_Stream_Input
5593 and then TSS_Name /= TSS_Stream_Output
5595 -- Here we have a definite conformance error. It is worth
5596 -- special casing the error message for the case of a
5597 -- controlling formal (which excludes null).
5599 if Is_Controlling_Formal (New_Formal) then
5600 Error_Msg_Node_2 := Scope (New_Formal);
5602 ("\controlling formal & of & excludes null, "
5603 & "declaration must exclude null as well",
5606 -- Normal case (couldn't we give more detail here???)
5610 ("\type of & does not match!", New_Formal);
5619 -- Full conformance checks
5621 if Ctype = Fully_Conformant then
5623 -- We have checked already that names match
5625 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5627 -- Check default expressions for in parameters
5630 NewD : constant Boolean :=
5631 Present (Default_Value (New_Formal));
5632 OldD : constant Boolean :=
5633 Present (Default_Value (Old_Formal));
5635 if NewD or OldD then
5637 -- The old default value has been analyzed because the
5638 -- current full declaration will have frozen everything
5639 -- before. The new default value has not been analyzed,
5640 -- so analyze it now before we check for conformance.
5643 Push_Scope (New_Id);
5644 Preanalyze_Spec_Expression
5645 (Default_Value (New_Formal), Etype (New_Formal));
5649 if not (NewD and OldD)
5650 or else not Fully_Conformant_Expressions
5651 (Default_Value (Old_Formal),
5652 Default_Value (New_Formal))
5655 ("\default expression for & does not match!",
5664 -- A couple of special checks for Ada 83 mode. These checks are
5665 -- skipped if either entity is an operator in package Standard,
5666 -- or if either old or new instance is not from the source program.
5668 if Ada_Version = Ada_83
5669 and then Sloc (Old_Id) > Standard_Location
5670 and then Sloc (New_Id) > Standard_Location
5671 and then Comes_From_Source (Old_Id)
5672 and then Comes_From_Source (New_Id)
5675 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5676 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5679 -- Explicit IN must be present or absent in both cases. This
5680 -- test is required only in the full conformance case.
5682 if In_Present (Old_Param) /= In_Present (New_Param)
5683 and then Ctype = Fully_Conformant
5686 ("\(Ada 83) IN must appear in both declarations",
5691 -- Grouping (use of comma in param lists) must be the same
5692 -- This is where we catch a misconformance like:
5695 -- A : Integer; B : Integer
5697 -- which are represented identically in the tree except
5698 -- for the setting of the flags More_Ids and Prev_Ids.
5700 if More_Ids (Old_Param) /= More_Ids (New_Param)
5701 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5704 ("\grouping of & does not match!", New_Formal);
5710 -- This label is required when skipping controlling formals
5712 <<Skip_Controlling_Formal>>
5714 Next_Formal (Old_Formal);
5715 Next_Formal (New_Formal);
5718 if Present (Old_Formal) then
5719 Conformance_Error ("\too few parameters!");
5722 elsif Present (New_Formal) then
5723 Conformance_Error ("\too many parameters!", New_Formal);
5726 end Check_Conformance;
5728 -----------------------
5729 -- Check_Conventions --
5730 -----------------------
5732 procedure Check_Conventions (Typ : Entity_Id) is
5733 Ifaces_List : Elist_Id;
5735 procedure Check_Convention (Op : Entity_Id);
5736 -- Verify that the convention of inherited dispatching operation Op is
5737 -- consistent among all subprograms it overrides. In order to minimize
5738 -- the search, Search_From is utilized to designate a specific point in
5739 -- the list rather than iterating over the whole list once more.
5741 ----------------------
5742 -- Check_Convention --
5743 ----------------------
5745 procedure Check_Convention (Op : Entity_Id) is
5746 Op_Conv : constant Convention_Id := Convention (Op);
5747 Iface_Conv : Convention_Id;
5748 Iface_Elmt : Elmt_Id;
5749 Iface_Prim_Elmt : Elmt_Id;
5750 Iface_Prim : Entity_Id;
5753 Iface_Elmt := First_Elmt (Ifaces_List);
5754 while Present (Iface_Elmt) loop
5756 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5757 while Present (Iface_Prim_Elmt) loop
5758 Iface_Prim := Node (Iface_Prim_Elmt);
5759 Iface_Conv := Convention (Iface_Prim);
5761 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5762 and then Iface_Conv /= Op_Conv
5765 ("inconsistent conventions in primitive operations", Typ);
5767 Error_Msg_Name_1 := Chars (Op);
5768 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5769 Error_Msg_Sloc := Sloc (Op);
5771 if Comes_From_Source (Op) or else No (Alias (Op)) then
5772 if not Present (Overridden_Operation (Op)) then
5773 Error_Msg_N ("\\primitive % defined #", Typ);
5776 ("\\overriding operation % with "
5777 & "convention % defined #", Typ);
5780 else pragma Assert (Present (Alias (Op)));
5781 Error_Msg_Sloc := Sloc (Alias (Op));
5782 Error_Msg_N ("\\inherited operation % with "
5783 & "convention % defined #", Typ);
5786 Error_Msg_Name_1 := Chars (Op);
5787 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5788 Error_Msg_Sloc := Sloc (Iface_Prim);
5789 Error_Msg_N ("\\overridden operation % with "
5790 & "convention % defined #", Typ);
5792 -- Avoid cascading errors
5797 Next_Elmt (Iface_Prim_Elmt);
5800 Next_Elmt (Iface_Elmt);
5802 end Check_Convention;
5806 Prim_Op : Entity_Id;
5807 Prim_Op_Elmt : Elmt_Id;
5809 -- Start of processing for Check_Conventions
5812 if not Has_Interfaces (Typ) then
5816 Collect_Interfaces (Typ, Ifaces_List);
5818 -- The algorithm checks every overriding dispatching operation against
5819 -- all the corresponding overridden dispatching operations, detecting
5820 -- differences in conventions.
5822 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5823 while Present (Prim_Op_Elmt) loop
5824 Prim_Op := Node (Prim_Op_Elmt);
5826 -- A small optimization: skip the predefined dispatching operations
5827 -- since they always have the same convention.
5829 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5830 Check_Convention (Prim_Op);
5833 Next_Elmt (Prim_Op_Elmt);
5835 end Check_Conventions;
5837 ------------------------------
5838 -- Check_Delayed_Subprogram --
5839 ------------------------------
5841 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5842 procedure Possible_Freeze (T : Entity_Id);
5843 -- T is the type of either a formal parameter or of the return type. If
5844 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5845 -- itself must be delayed.
5847 ---------------------
5848 -- Possible_Freeze --
5849 ---------------------
5851 procedure Possible_Freeze (T : Entity_Id) is
5852 Scop : constant Entity_Id := Scope (Designator);
5855 -- If the subprogram appears within a package instance (which may be
5856 -- the wrapper package of a subprogram instance) the freeze node for
5857 -- that package will freeze the subprogram at the proper place, so
5858 -- do not emit a freeze node for the subprogram, given that it may
5859 -- appear in the wrong scope.
5861 if Ekind (Scop) = E_Package
5862 and then not Comes_From_Source (Scop)
5863 and then Is_Generic_Instance (Scop)
5867 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5868 Set_Has_Delayed_Freeze (Designator);
5870 elsif Is_Access_Type (T)
5871 and then Has_Delayed_Freeze (Designated_Type (T))
5872 and then not Is_Frozen (Designated_Type (T))
5874 Set_Has_Delayed_Freeze (Designator);
5876 end Possible_Freeze;
5882 -- Start of processing for Check_Delayed_Subprogram
5885 -- All subprograms, including abstract subprograms, may need a freeze
5886 -- node if some formal type or the return type needs one.
5888 Possible_Freeze (Etype (Designator));
5889 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5891 -- Need delayed freeze if any of the formal types themselves need a
5892 -- delayed freeze and are not yet frozen.
5894 F := First_Formal (Designator);
5895 while Present (F) loop
5896 Possible_Freeze (Etype (F));
5897 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5901 -- Mark functions that return by reference. Note that it cannot be done
5902 -- for delayed_freeze subprograms because the underlying returned type
5903 -- may not be known yet (for private types).
5905 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5907 Typ : constant Entity_Id := Etype (Designator);
5908 Utyp : constant Entity_Id := Underlying_Type (Typ);
5911 if Is_Limited_View (Typ) then
5912 Set_Returns_By_Ref (Designator);
5914 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5915 Set_Returns_By_Ref (Designator);
5919 end Check_Delayed_Subprogram;
5921 ------------------------------------
5922 -- Check_Discriminant_Conformance --
5923 ------------------------------------
5925 procedure Check_Discriminant_Conformance
5930 Old_Discr : Entity_Id := First_Discriminant (Prev);
5931 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5932 New_Discr_Id : Entity_Id;
5933 New_Discr_Type : Entity_Id;
5935 procedure Conformance_Error (Msg : String; N : Node_Id);
5936 -- Post error message for conformance error on given node. Two messages
5937 -- are output. The first points to the previous declaration with a
5938 -- general "no conformance" message. The second is the detailed reason,
5939 -- supplied as Msg. The parameter N provide information for a possible
5940 -- & insertion in the message.
5942 -----------------------
5943 -- Conformance_Error --
5944 -----------------------
5946 procedure Conformance_Error (Msg : String; N : Node_Id) is
5948 Error_Msg_Sloc := Sloc (Prev_Loc);
5949 Error_Msg_N -- CODEFIX
5950 ("not fully conformant with declaration#!", N);
5951 Error_Msg_NE (Msg, N, N);
5952 end Conformance_Error;
5954 -- Start of processing for Check_Discriminant_Conformance
5957 while Present (Old_Discr) and then Present (New_Discr) loop
5958 New_Discr_Id := Defining_Identifier (New_Discr);
5960 -- The subtype mark of the discriminant on the full type has not
5961 -- been analyzed so we do it here. For an access discriminant a new
5964 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5966 Access_Definition (N, Discriminant_Type (New_Discr));
5969 Analyze (Discriminant_Type (New_Discr));
5970 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
5972 -- Ada 2005: if the discriminant definition carries a null
5973 -- exclusion, create an itype to check properly for consistency
5974 -- with partial declaration.
5976 if Is_Access_Type (New_Discr_Type)
5977 and then Null_Exclusion_Present (New_Discr)
5980 Create_Null_Excluding_Itype
5981 (T => New_Discr_Type,
5982 Related_Nod => New_Discr,
5983 Scope_Id => Current_Scope);
5987 if not Conforming_Types
5988 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
5990 Conformance_Error ("type of & does not match!", New_Discr_Id);
5993 -- Treat the new discriminant as an occurrence of the old one,
5994 -- for navigation purposes, and fill in some semantic
5995 -- information, for completeness.
5997 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
5998 Set_Etype (New_Discr_Id, Etype (Old_Discr));
5999 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6004 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6005 Conformance_Error ("name & does not match!", New_Discr_Id);
6009 -- Default expressions must match
6012 NewD : constant Boolean :=
6013 Present (Expression (New_Discr));
6014 OldD : constant Boolean :=
6015 Present (Expression (Parent (Old_Discr)));
6018 if NewD or OldD then
6020 -- The old default value has been analyzed and expanded,
6021 -- because the current full declaration will have frozen
6022 -- everything before. The new default values have not been
6023 -- expanded, so expand now to check conformance.
6026 Preanalyze_Spec_Expression
6027 (Expression (New_Discr), New_Discr_Type);
6030 if not (NewD and OldD)
6031 or else not Fully_Conformant_Expressions
6032 (Expression (Parent (Old_Discr)),
6033 Expression (New_Discr))
6037 ("default expression for & does not match!",
6044 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6046 if Ada_Version = Ada_83 then
6048 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6051 -- Grouping (use of comma in param lists) must be the same
6052 -- This is where we catch a misconformance like:
6055 -- A : Integer; B : Integer
6057 -- which are represented identically in the tree except
6058 -- for the setting of the flags More_Ids and Prev_Ids.
6060 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6061 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6064 ("grouping of & does not match!", New_Discr_Id);
6070 Next_Discriminant (Old_Discr);
6074 if Present (Old_Discr) then
6075 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6078 elsif Present (New_Discr) then
6080 ("too many discriminants!", Defining_Identifier (New_Discr));
6083 end Check_Discriminant_Conformance;
6085 ----------------------------
6086 -- Check_Fully_Conformant --
6087 ----------------------------
6089 procedure Check_Fully_Conformant
6090 (New_Id : Entity_Id;
6092 Err_Loc : Node_Id := Empty)
6095 pragma Warnings (Off, Result);
6098 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6099 end Check_Fully_Conformant;
6101 --------------------------
6102 -- Check_Limited_Return --
6103 --------------------------
6105 procedure Check_Limited_Return
6111 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6112 -- replaced by anonymous access results. This is an incompatibility with
6113 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6114 -- controllable with special switch. ???
6116 -- A limited interface that is not immutably limited is OK
6118 if Is_Limited_Interface (R_Type)
6120 not (Is_Task_Interface (R_Type)
6121 or else Is_Protected_Interface (R_Type)
6122 or else Is_Synchronized_Interface (R_Type))
6126 elsif Is_Limited_Type (R_Type)
6127 and then not Is_Interface (R_Type)
6128 and then Comes_From_Source (N)
6129 and then not In_Instance_Body
6130 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6132 -- Error in Ada 2005
6134 if Ada_Version >= Ada_2005
6135 and then not Debug_Flag_Dot_L
6136 and then not GNAT_Mode
6139 ("(Ada 2005) cannot copy object of a limited type "
6140 & "(RM-2005 6.5(5.5/2))", Expr);
6142 if Is_Limited_View (R_Type) then
6144 ("\return by reference not permitted in Ada 2005", Expr);
6147 -- Warn in Ada 95 mode, to give folks a heads up about this
6150 -- In GNAT mode, this is just a warning, to allow it to be evilly
6151 -- turned off. Otherwise it is a real error.
6153 -- In a generic context, simplify the warning because it makes no
6154 -- sense to discuss pass-by-reference or copy.
6156 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6157 if Inside_A_Generic then
6159 ("return of limited object not permitted in Ada 2005 "
6160 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6162 elsif Is_Limited_View (R_Type) then
6164 ("return by reference not permitted in Ada 2005 "
6165 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6168 ("cannot copy object of a limited type in Ada 2005 "
6169 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6172 -- Ada 95 mode, and compatibility warnings disabled
6175 pragma Assert (Ada_Version <= Ada_95);
6176 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6177 return; -- skip continuation messages below
6180 if not Inside_A_Generic then
6182 ("\consider switching to return of access type", Expr);
6183 Explain_Limited_Type (R_Type, Expr);
6186 end Check_Limited_Return;
6188 ---------------------------
6189 -- Check_Mode_Conformant --
6190 ---------------------------
6192 procedure Check_Mode_Conformant
6193 (New_Id : Entity_Id;
6195 Err_Loc : Node_Id := Empty;
6196 Get_Inst : Boolean := False)
6199 pragma Warnings (Off, Result);
6202 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6203 end Check_Mode_Conformant;
6205 --------------------------------
6206 -- Check_Overriding_Indicator --
6207 --------------------------------
6209 procedure Check_Overriding_Indicator
6211 Overridden_Subp : Entity_Id;
6212 Is_Primitive : Boolean)
6218 -- No overriding indicator for literals
6220 if Ekind (Subp) = E_Enumeration_Literal then
6223 elsif Ekind (Subp) = E_Entry then
6224 Decl := Parent (Subp);
6226 -- No point in analyzing a malformed operator
6228 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6229 and then Error_Posted (Subp)
6234 Decl := Unit_Declaration_Node (Subp);
6237 if Nkind_In (Decl, N_Subprogram_Body,
6238 N_Subprogram_Body_Stub,
6239 N_Subprogram_Declaration,
6240 N_Abstract_Subprogram_Declaration,
6241 N_Subprogram_Renaming_Declaration)
6243 Spec := Specification (Decl);
6245 elsif Nkind (Decl) = N_Entry_Declaration then
6252 -- The overriding operation is type conformant with the overridden one,
6253 -- but the names of the formals are not required to match. If the names
6254 -- appear permuted in the overriding operation, this is a possible
6255 -- source of confusion that is worth diagnosing. Controlling formals
6256 -- often carry names that reflect the type, and it is not worthwhile
6257 -- requiring that their names match.
6259 if Present (Overridden_Subp)
6260 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6267 Form1 := First_Formal (Subp);
6268 Form2 := First_Formal (Overridden_Subp);
6270 -- If the overriding operation is a synchronized operation, skip
6271 -- the first parameter of the overridden operation, which is
6272 -- implicit in the new one. If the operation is declared in the
6273 -- body it is not primitive and all formals must match.
6275 if Is_Concurrent_Type (Scope (Subp))
6276 and then Is_Tagged_Type (Scope (Subp))
6277 and then not Has_Completion (Scope (Subp))
6279 Form2 := Next_Formal (Form2);
6282 if Present (Form1) then
6283 Form1 := Next_Formal (Form1);
6284 Form2 := Next_Formal (Form2);
6287 while Present (Form1) loop
6288 if not Is_Controlling_Formal (Form1)
6289 and then Present (Next_Formal (Form2))
6290 and then Chars (Form1) = Chars (Next_Formal (Form2))
6292 Error_Msg_Node_2 := Alias (Overridden_Subp);
6293 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6295 ("& does not match corresponding formal of&#",
6300 Next_Formal (Form1);
6301 Next_Formal (Form2);
6306 -- If there is an overridden subprogram, then check that there is no
6307 -- "not overriding" indicator, and mark the subprogram as overriding.
6308 -- This is not done if the overridden subprogram is marked as hidden,
6309 -- which can occur for the case of inherited controlled operations
6310 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6311 -- subprogram is not itself hidden. (Note: This condition could probably
6312 -- be simplified, leaving out the testing for the specific controlled
6313 -- cases, but it seems safer and clearer this way, and echoes similar
6314 -- special-case tests of this kind in other places.)
6316 if Present (Overridden_Subp)
6317 and then (not Is_Hidden (Overridden_Subp)
6319 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6322 and then Present (Alias (Overridden_Subp))
6323 and then not Is_Hidden (Alias (Overridden_Subp))))
6325 if Must_Not_Override (Spec) then
6326 Error_Msg_Sloc := Sloc (Overridden_Subp);
6328 if Ekind (Subp) = E_Entry then
6330 ("entry & overrides inherited operation #", Spec, Subp);
6333 ("subprogram & overrides inherited operation #", Spec, Subp);
6336 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6337 -- as an extension of Root_Controlled, and thus has a useless Adjust
6338 -- operation. This operation should not be inherited by other limited
6339 -- controlled types. An explicit Adjust for them is not overriding.
6341 elsif Must_Override (Spec)
6342 and then Chars (Overridden_Subp) = Name_Adjust
6343 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6344 and then Present (Alias (Overridden_Subp))
6345 and then In_Predefined_Unit (Alias (Overridden_Subp))
6348 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6349 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6351 elsif Is_Subprogram (Subp) then
6352 if Is_Init_Proc (Subp) then
6355 elsif No (Overridden_Operation (Subp)) then
6357 -- For entities generated by Derive_Subprograms the overridden
6358 -- operation is the inherited primitive (which is available
6359 -- through the attribute alias)
6361 if (Is_Dispatching_Operation (Subp)
6362 or else Is_Dispatching_Operation (Overridden_Subp))
6363 and then not Comes_From_Source (Overridden_Subp)
6364 and then Find_Dispatching_Type (Overridden_Subp) =
6365 Find_Dispatching_Type (Subp)
6366 and then Present (Alias (Overridden_Subp))
6367 and then Comes_From_Source (Alias (Overridden_Subp))
6369 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6370 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6373 Set_Overridden_Operation (Subp, Overridden_Subp);
6374 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6379 -- If primitive flag is set or this is a protected operation, then
6380 -- the operation is overriding at the point of its declaration, so
6381 -- warn if necessary. Otherwise it may have been declared before the
6382 -- operation it overrides and no check is required.
6385 and then not Must_Override (Spec)
6386 and then (Is_Primitive
6387 or else Ekind (Scope (Subp)) = E_Protected_Type)
6389 Style.Missing_Overriding (Decl, Subp);
6392 -- If Subp is an operator, it may override a predefined operation, if
6393 -- it is defined in the same scope as the type to which it applies.
6394 -- In that case Overridden_Subp is empty because of our implicit
6395 -- representation for predefined operators. We have to check whether the
6396 -- signature of Subp matches that of a predefined operator. Note that
6397 -- first argument provides the name of the operator, and the second
6398 -- argument the signature that may match that of a standard operation.
6399 -- If the indicator is overriding, then the operator must match a
6400 -- predefined signature, because we know already that there is no
6401 -- explicit overridden operation.
6403 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6404 if Must_Not_Override (Spec) then
6406 -- If this is not a primitive or a protected subprogram, then
6407 -- "not overriding" is illegal.
6410 and then Ekind (Scope (Subp)) /= E_Protected_Type
6412 Error_Msg_N ("overriding indicator only allowed "
6413 & "if subprogram is primitive", Subp);
6415 elsif Can_Override_Operator (Subp) then
6417 ("subprogram& overrides predefined operator ", Spec, Subp);
6420 elsif Must_Override (Spec) then
6421 if No (Overridden_Operation (Subp))
6422 and then not Can_Override_Operator (Subp)
6424 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6427 elsif not Error_Posted (Subp)
6428 and then Style_Check
6429 and then Can_Override_Operator (Subp)
6430 and then not In_Predefined_Unit (Subp)
6432 -- If style checks are enabled, indicate that the indicator is
6433 -- missing. However, at the point of declaration, the type of
6434 -- which this is a primitive operation may be private, in which
6435 -- case the indicator would be premature.
6437 if Has_Private_Declaration (Etype (Subp))
6438 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6442 Style.Missing_Overriding (Decl, Subp);
6446 elsif Must_Override (Spec) then
6447 if Ekind (Subp) = E_Entry then
6448 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6450 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6453 -- If the operation is marked "not overriding" and it's not primitive
6454 -- then an error is issued, unless this is an operation of a task or
6455 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6456 -- has been specified have already been checked above.
6458 elsif Must_Not_Override (Spec)
6459 and then not Is_Primitive
6460 and then Ekind (Subp) /= E_Entry
6461 and then Ekind (Scope (Subp)) /= E_Protected_Type
6464 ("overriding indicator only allowed if subprogram is primitive",
6468 end Check_Overriding_Indicator;
6474 -- Note: this procedure needs to know far too much about how the expander
6475 -- messes with exceptions. The use of the flag Exception_Junk and the
6476 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6477 -- works, but is not very clean. It would be better if the expansion
6478 -- routines would leave Original_Node working nicely, and we could use
6479 -- Original_Node here to ignore all the peculiar expander messing ???
6481 procedure Check_Returns
6485 Proc : Entity_Id := Empty)
6489 procedure Check_Statement_Sequence (L : List_Id);
6490 -- Internal recursive procedure to check a list of statements for proper
6491 -- termination by a return statement (or a transfer of control or a
6492 -- compound statement that is itself internally properly terminated).
6494 ------------------------------
6495 -- Check_Statement_Sequence --
6496 ------------------------------
6498 procedure Check_Statement_Sequence (L : List_Id) is
6503 function Assert_False return Boolean;
6504 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6505 -- rewritten as a null statement when assertions are off. The assert
6506 -- is not active, but it is still enough to kill the warning.
6512 function Assert_False return Boolean is
6513 Orig : constant Node_Id := Original_Node (Last_Stm);
6516 if Nkind (Orig) = N_Pragma
6517 and then Pragma_Name (Orig) = Name_Assert
6518 and then not Error_Posted (Orig)
6521 Arg : constant Node_Id :=
6522 First (Pragma_Argument_Associations (Orig));
6523 Exp : constant Node_Id := Expression (Arg);
6525 return Nkind (Exp) = N_Identifier
6526 and then Chars (Exp) = Name_False;
6536 Raise_Exception_Call : Boolean;
6537 -- Set True if statement sequence terminated by Raise_Exception call
6538 -- or a Reraise_Occurrence call.
6540 -- Start of processing for Check_Statement_Sequence
6543 Raise_Exception_Call := False;
6545 -- Get last real statement
6547 Last_Stm := Last (L);
6549 -- Deal with digging out exception handler statement sequences that
6550 -- have been transformed by the local raise to goto optimization.
6551 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6552 -- optimization has occurred, we are looking at something like:
6555 -- original stmts in block
6559 -- goto L1; | omitted if No_Exception_Propagation
6564 -- goto L3; -- skip handler when exception not raised
6566 -- <<L1>> -- target label for local exception
6580 -- and what we have to do is to dig out the estmts1 and estmts2
6581 -- sequences (which were the original sequences of statements in
6582 -- the exception handlers) and check them.
6584 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6589 exit when Nkind (Stm) /= N_Block_Statement;
6590 exit when not Exception_Junk (Stm);
6593 exit when Nkind (Stm) /= N_Label;
6594 exit when not Exception_Junk (Stm);
6595 Check_Statement_Sequence
6596 (Statements (Handled_Statement_Sequence (Next (Stm))));
6601 exit when Nkind (Stm) /= N_Goto_Statement;
6602 exit when not Exception_Junk (Stm);
6606 -- Don't count pragmas
6608 while Nkind (Last_Stm) = N_Pragma
6610 -- Don't count call to SS_Release (can happen after Raise_Exception)
6613 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6615 Nkind (Name (Last_Stm)) = N_Identifier
6617 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6619 -- Don't count exception junk
6622 (Nkind_In (Last_Stm, N_Goto_Statement,
6624 N_Object_Declaration)
6625 and then Exception_Junk (Last_Stm))
6626 or else Nkind (Last_Stm) in N_Push_xxx_Label
6627 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6629 -- Inserted code, such as finalization calls, is irrelevant: we only
6630 -- need to check original source.
6632 or else Is_Rewrite_Insertion (Last_Stm)
6637 -- Here we have the "real" last statement
6639 Kind := Nkind (Last_Stm);
6641 -- Transfer of control, OK. Note that in the No_Return procedure
6642 -- case, we already diagnosed any explicit return statements, so
6643 -- we can treat them as OK in this context.
6645 if Is_Transfer (Last_Stm) then
6648 -- Check cases of explicit non-indirect procedure calls
6650 elsif Kind = N_Procedure_Call_Statement
6651 and then Is_Entity_Name (Name (Last_Stm))
6653 -- Check call to Raise_Exception procedure which is treated
6654 -- specially, as is a call to Reraise_Occurrence.
6656 -- We suppress the warning in these cases since it is likely that
6657 -- the programmer really does not expect to deal with the case
6658 -- of Null_Occurrence, and thus would find a warning about a
6659 -- missing return curious, and raising Program_Error does not
6660 -- seem such a bad behavior if this does occur.
6662 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6663 -- behavior will be to raise Constraint_Error (see AI-329).
6665 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6667 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6669 Raise_Exception_Call := True;
6671 -- For Raise_Exception call, test first argument, if it is
6672 -- an attribute reference for a 'Identity call, then we know
6673 -- that the call cannot possibly return.
6676 Arg : constant Node_Id :=
6677 Original_Node (First_Actual (Last_Stm));
6679 if Nkind (Arg) = N_Attribute_Reference
6680 and then Attribute_Name (Arg) = Name_Identity
6687 -- If statement, need to look inside if there is an else and check
6688 -- each constituent statement sequence for proper termination.
6690 elsif Kind = N_If_Statement
6691 and then Present (Else_Statements (Last_Stm))
6693 Check_Statement_Sequence (Then_Statements (Last_Stm));
6694 Check_Statement_Sequence (Else_Statements (Last_Stm));
6696 if Present (Elsif_Parts (Last_Stm)) then
6698 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6701 while Present (Elsif_Part) loop
6702 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6710 -- Case statement, check each case for proper termination
6712 elsif Kind = N_Case_Statement then
6716 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6717 while Present (Case_Alt) loop
6718 Check_Statement_Sequence (Statements (Case_Alt));
6719 Next_Non_Pragma (Case_Alt);
6725 -- Block statement, check its handled sequence of statements
6727 elsif Kind = N_Block_Statement then
6733 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6742 -- Loop statement. If there is an iteration scheme, we can definitely
6743 -- fall out of the loop. Similarly if there is an exit statement, we
6744 -- can fall out. In either case we need a following return.
6746 elsif Kind = N_Loop_Statement then
6747 if Present (Iteration_Scheme (Last_Stm))
6748 or else Has_Exit (Entity (Identifier (Last_Stm)))
6752 -- A loop with no exit statement or iteration scheme is either
6753 -- an infinite loop, or it has some other exit (raise/return).
6754 -- In either case, no warning is required.
6760 -- Timed entry call, check entry call and delay alternatives
6762 -- Note: in expanded code, the timed entry call has been converted
6763 -- to a set of expanded statements on which the check will work
6764 -- correctly in any case.
6766 elsif Kind = N_Timed_Entry_Call then
6768 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6769 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6772 -- If statement sequence of entry call alternative is missing,
6773 -- then we can definitely fall through, and we post the error
6774 -- message on the entry call alternative itself.
6776 if No (Statements (ECA)) then
6779 -- If statement sequence of delay alternative is missing, then
6780 -- we can definitely fall through, and we post the error
6781 -- message on the delay alternative itself.
6783 -- Note: if both ECA and DCA are missing the return, then we
6784 -- post only one message, should be enough to fix the bugs.
6785 -- If not we will get a message next time on the DCA when the
6788 elsif No (Statements (DCA)) then
6791 -- Else check both statement sequences
6794 Check_Statement_Sequence (Statements (ECA));
6795 Check_Statement_Sequence (Statements (DCA));
6800 -- Conditional entry call, check entry call and else part
6802 -- Note: in expanded code, the conditional entry call has been
6803 -- converted to a set of expanded statements on which the check
6804 -- will work correctly in any case.
6806 elsif Kind = N_Conditional_Entry_Call then
6808 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6811 -- If statement sequence of entry call alternative is missing,
6812 -- then we can definitely fall through, and we post the error
6813 -- message on the entry call alternative itself.
6815 if No (Statements (ECA)) then
6818 -- Else check statement sequence and else part
6821 Check_Statement_Sequence (Statements (ECA));
6822 Check_Statement_Sequence (Else_Statements (Last_Stm));
6828 -- If we fall through, issue appropriate message
6832 -- Kill warning if last statement is a raise exception call,
6833 -- or a pragma Assert (False). Note that with assertions enabled,
6834 -- such a pragma has been converted into a raise exception call
6835 -- already, so the Assert_False is for the assertions off case.
6837 if not Raise_Exception_Call and then not Assert_False then
6839 -- In GNATprove mode, it is an error to have a missing return
6841 Error_Msg_Warn := SPARK_Mode /= On;
6843 -- Issue error message or warning
6846 ("RETURN statement missing following this statement<<!",
6849 ("\Program_Error ]<<!", Last_Stm);
6852 -- Note: we set Err even though we have not issued a warning
6853 -- because we still have a case of a missing return. This is
6854 -- an extremely marginal case, probably will never be noticed
6855 -- but we might as well get it right.
6859 -- Otherwise we have the case of a procedure marked No_Return
6862 if not Raise_Exception_Call then
6863 if GNATprove_Mode then
6865 ("implied return after this statement would have raised "
6866 & "Program_Error", Last_Stm);
6868 -- In normal compilation mode, do not warn on a generated call
6869 -- (e.g. in the body of a renaming as completion).
6871 elsif Comes_From_Source (Last_Stm) then
6873 ("implied return after this statement will raise "
6874 & "Program_Error??", Last_Stm);
6877 Error_Msg_Warn := SPARK_Mode /= On;
6879 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6883 RE : constant Node_Id :=
6884 Make_Raise_Program_Error (Sloc (Last_Stm),
6885 Reason => PE_Implicit_Return);
6887 Insert_After (Last_Stm, RE);
6891 end Check_Statement_Sequence;
6893 -- Start of processing for Check_Returns
6897 Check_Statement_Sequence (Statements (HSS));
6899 if Present (Exception_Handlers (HSS)) then
6900 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6901 while Present (Handler) loop
6902 Check_Statement_Sequence (Statements (Handler));
6903 Next_Non_Pragma (Handler);
6908 ----------------------------
6909 -- Check_Subprogram_Order --
6910 ----------------------------
6912 procedure Check_Subprogram_Order (N : Node_Id) is
6914 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6915 -- This is used to check if S1 > S2 in the sense required by this test,
6916 -- for example nameab < namec, but name2 < name10.
6918 -----------------------------
6919 -- Subprogram_Name_Greater --
6920 -----------------------------
6922 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6927 -- Deal with special case where names are identical except for a
6928 -- numerical suffix. These are handled specially, taking the numeric
6929 -- ordering from the suffix into account.
6932 while S1 (L1) in '0' .. '9' loop
6937 while S2 (L2) in '0' .. '9' loop
6941 -- If non-numeric parts non-equal, do straight compare
6943 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6946 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6947 -- that a missing suffix is treated as numeric zero in this test.
6951 while L1 < S1'Last loop
6953 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6957 while L2 < S2'Last loop
6959 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6964 end Subprogram_Name_Greater;
6966 -- Start of processing for Check_Subprogram_Order
6969 -- Check body in alpha order if this is option
6972 and then Style_Check_Order_Subprograms
6973 and then Nkind (N) = N_Subprogram_Body
6974 and then Comes_From_Source (N)
6975 and then In_Extended_Main_Source_Unit (N)
6979 renames Scope_Stack.Table
6980 (Scope_Stack.Last).Last_Subprogram_Name;
6982 Body_Id : constant Entity_Id :=
6983 Defining_Entity (Specification (N));
6986 Get_Decoded_Name_String (Chars (Body_Id));
6989 if Subprogram_Name_Greater
6990 (LSN.all, Name_Buffer (1 .. Name_Len))
6992 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
6998 LSN := new String'(Name_Buffer (1 .. Name_Len));
7001 end Check_Subprogram_Order;
7003 ------------------------------
7004 -- Check_Subtype_Conformant --
7005 ------------------------------
7007 procedure Check_Subtype_Conformant
7008 (New_Id : Entity_Id;
7010 Err_Loc : Node_Id := Empty;
7011 Skip_Controlling_Formals : Boolean := False;
7012 Get_Inst : Boolean := False)
7015 pragma Warnings (Off, Result);
7018 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7019 Skip_Controlling_Formals => Skip_Controlling_Formals,
7020 Get_Inst => Get_Inst);
7021 end Check_Subtype_Conformant;
7023 -----------------------------------
7024 -- Check_Synchronized_Overriding --
7025 -----------------------------------
7027 procedure Check_Synchronized_Overriding
7028 (Def_Id : Entity_Id;
7029 Overridden_Subp : out Entity_Id)
7031 Ifaces_List : Elist_Id;
7035 function Matches_Prefixed_View_Profile
7036 (Prim_Params : List_Id;
7037 Iface_Params : List_Id) return Boolean;
7038 -- Determine whether a subprogram's parameter profile Prim_Params
7039 -- matches that of a potentially overridden interface subprogram
7040 -- Iface_Params. Also determine if the type of first parameter of
7041 -- Iface_Params is an implemented interface.
7043 -----------------------------------
7044 -- Matches_Prefixed_View_Profile --
7045 -----------------------------------
7047 function Matches_Prefixed_View_Profile
7048 (Prim_Params : List_Id;
7049 Iface_Params : List_Id) return Boolean
7051 function Is_Implemented
7052 (Ifaces_List : Elist_Id;
7053 Iface : Entity_Id) return Boolean;
7054 -- Determine if Iface is implemented by the current task or
7057 --------------------
7058 -- Is_Implemented --
7059 --------------------
7061 function Is_Implemented
7062 (Ifaces_List : Elist_Id;
7063 Iface : Entity_Id) return Boolean
7065 Iface_Elmt : Elmt_Id;
7068 Iface_Elmt := First_Elmt (Ifaces_List);
7069 while Present (Iface_Elmt) loop
7070 if Node (Iface_Elmt) = Iface then
7074 Next_Elmt (Iface_Elmt);
7082 Iface_Id : Entity_Id;
7083 Iface_Param : Node_Id;
7084 Iface_Typ : Entity_Id;
7085 Prim_Id : Entity_Id;
7086 Prim_Param : Node_Id;
7087 Prim_Typ : Entity_Id;
7089 -- Start of processing for Matches_Prefixed_View_Profile
7092 Iface_Param := First (Iface_Params);
7093 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7095 if Is_Access_Type (Iface_Typ) then
7096 Iface_Typ := Designated_Type (Iface_Typ);
7099 Prim_Param := First (Prim_Params);
7101 -- The first parameter of the potentially overridden subprogram must
7102 -- be an interface implemented by Prim.
7104 if not Is_Interface (Iface_Typ)
7105 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7110 -- The checks on the object parameters are done, so move on to the
7111 -- rest of the parameters.
7113 if not In_Scope then
7114 Prim_Param := Next (Prim_Param);
7117 Iface_Param := Next (Iface_Param);
7118 while Present (Iface_Param) and then Present (Prim_Param) loop
7119 Iface_Id := Defining_Identifier (Iface_Param);
7120 Iface_Typ := Find_Parameter_Type (Iface_Param);
7122 Prim_Id := Defining_Identifier (Prim_Param);
7123 Prim_Typ := Find_Parameter_Type (Prim_Param);
7125 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7126 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7127 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7129 Iface_Typ := Designated_Type (Iface_Typ);
7130 Prim_Typ := Designated_Type (Prim_Typ);
7133 -- Case of multiple interface types inside a parameter profile
7135 -- (Obj_Param : in out Iface; ...; Param : Iface)
7137 -- If the interface type is implemented, then the matching type in
7138 -- the primitive should be the implementing record type.
7140 if Ekind (Iface_Typ) = E_Record_Type
7141 and then Is_Interface (Iface_Typ)
7142 and then Is_Implemented (Ifaces_List, Iface_Typ)
7144 if Prim_Typ /= Typ then
7148 -- The two parameters must be both mode and subtype conformant
7150 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7152 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7161 -- One of the two lists contains more parameters than the other
7163 if Present (Iface_Param) or else Present (Prim_Param) then
7168 end Matches_Prefixed_View_Profile;
7170 -- Start of processing for Check_Synchronized_Overriding
7173 Overridden_Subp := Empty;
7175 -- Def_Id must be an entry or a subprogram. We should skip predefined
7176 -- primitives internally generated by the front end; however at this
7177 -- stage predefined primitives are still not fully decorated. As a
7178 -- minor optimization we skip here internally generated subprograms.
7180 if (Ekind (Def_Id) /= E_Entry
7181 and then Ekind (Def_Id) /= E_Function
7182 and then Ekind (Def_Id) /= E_Procedure)
7183 or else not Comes_From_Source (Def_Id)
7188 -- Search for the concurrent declaration since it contains the list of
7189 -- all implemented interfaces. In this case, the subprogram is declared
7190 -- within the scope of a protected or a task type.
7192 if Present (Scope (Def_Id))
7193 and then Is_Concurrent_Type (Scope (Def_Id))
7194 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7196 Typ := Scope (Def_Id);
7199 -- The enclosing scope is not a synchronized type and the subprogram
7202 elsif No (First_Formal (Def_Id)) then
7205 -- The subprogram has formals and hence it may be a primitive of a
7209 Typ := Etype (First_Formal (Def_Id));
7211 if Is_Access_Type (Typ) then
7212 Typ := Directly_Designated_Type (Typ);
7215 if Is_Concurrent_Type (Typ)
7216 and then not Is_Generic_Actual_Type (Typ)
7220 -- This case occurs when the concurrent type is declared within a
7221 -- generic unit. As a result the corresponding record has been built
7222 -- and used as the type of the first formal, we just have to retrieve
7223 -- the corresponding concurrent type.
7225 elsif Is_Concurrent_Record_Type (Typ)
7226 and then not Is_Class_Wide_Type (Typ)
7227 and then Present (Corresponding_Concurrent_Type (Typ))
7229 Typ := Corresponding_Concurrent_Type (Typ);
7237 -- There is no overriding to check if this is an inherited operation in
7238 -- a type derivation for a generic actual.
7240 Collect_Interfaces (Typ, Ifaces_List);
7242 if Is_Empty_Elmt_List (Ifaces_List) then
7246 -- Determine whether entry or subprogram Def_Id overrides a primitive
7247 -- operation that belongs to one of the interfaces in Ifaces_List.
7250 Candidate : Entity_Id := Empty;
7251 Hom : Entity_Id := Empty;
7252 Subp : Entity_Id := Empty;
7255 -- Traverse the homonym chain, looking for a potentially overridden
7256 -- subprogram that belongs to an implemented interface.
7258 Hom := Current_Entity_In_Scope (Def_Id);
7259 while Present (Hom) loop
7263 or else not Is_Overloadable (Subp)
7264 or else not Is_Primitive (Subp)
7265 or else not Is_Dispatching_Operation (Subp)
7266 or else not Present (Find_Dispatching_Type (Subp))
7267 or else not Is_Interface (Find_Dispatching_Type (Subp))
7271 -- Entries and procedures can override abstract or null interface
7274 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7275 and then Ekind (Subp) = E_Procedure
7276 and then Matches_Prefixed_View_Profile
7277 (Parameter_Specifications (Parent (Def_Id)),
7278 Parameter_Specifications (Parent (Subp)))
7282 -- For an overridden subprogram Subp, check whether the mode
7283 -- of its first parameter is correct depending on the kind of
7284 -- synchronized type.
7287 Formal : constant Node_Id := First_Formal (Candidate);
7290 -- In order for an entry or a protected procedure to
7291 -- override, the first parameter of the overridden routine
7292 -- must be of mode "out", "in out", or access-to-variable.
7294 if Ekind_In (Candidate, E_Entry, E_Procedure)
7295 and then Is_Protected_Type (Typ)
7296 and then Ekind (Formal) /= E_In_Out_Parameter
7297 and then Ekind (Formal) /= E_Out_Parameter
7298 and then Nkind (Parameter_Type (Parent (Formal))) /=
7303 -- All other cases are OK since a task entry or routine does
7304 -- not have a restriction on the mode of the first parameter
7305 -- of the overridden interface routine.
7308 Overridden_Subp := Candidate;
7313 -- Functions can override abstract interface functions
7315 elsif Ekind (Def_Id) = E_Function
7316 and then Ekind (Subp) = E_Function
7317 and then Matches_Prefixed_View_Profile
7318 (Parameter_Specifications (Parent (Def_Id)),
7319 Parameter_Specifications (Parent (Subp)))
7320 and then Etype (Def_Id) = Etype (Subp)
7324 -- If an inherited subprogram is implemented by a protected
7325 -- function, then the first parameter of the inherited
7326 -- subprogram shall be of mode in, but not an access-to-
7327 -- variable parameter (RM 9.4(11/9)).
7329 if Present (First_Formal (Subp))
7330 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7332 (not Is_Access_Type (Etype (First_Formal (Subp)))
7334 Is_Access_Constant (Etype (First_Formal (Subp))))
7336 Overridden_Subp := Subp;
7341 Hom := Homonym (Hom);
7344 -- After examining all candidates for overriding, we are left with
7345 -- the best match, which is a mode-incompatible interface routine.
7347 if In_Scope and then Present (Candidate) then
7348 Error_Msg_PT (Def_Id, Candidate);
7351 Overridden_Subp := Candidate;
7354 end Check_Synchronized_Overriding;
7356 ---------------------------
7357 -- Check_Type_Conformant --
7358 ---------------------------
7360 procedure Check_Type_Conformant
7361 (New_Id : Entity_Id;
7363 Err_Loc : Node_Id := Empty)
7366 pragma Warnings (Off, Result);
7369 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7370 end Check_Type_Conformant;
7372 ---------------------------
7373 -- Can_Override_Operator --
7374 ---------------------------
7376 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7380 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7384 Typ := Base_Type (Etype (First_Formal (Subp)));
7386 -- Check explicitly that the operation is a primitive of the type
7388 return Operator_Matches_Spec (Subp, Subp)
7389 and then not Is_Generic_Type (Typ)
7390 and then Scope (Subp) = Scope (Typ)
7391 and then not Is_Class_Wide_Type (Typ);
7393 end Can_Override_Operator;
7395 ----------------------
7396 -- Conforming_Types --
7397 ----------------------
7399 function Conforming_Types
7402 Ctype : Conformance_Type;
7403 Get_Inst : Boolean := False) return Boolean
7405 function Base_Types_Match
7407 Typ_2 : Entity_Id) return Boolean;
7408 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7409 -- in different scopes (e.g. parent and child instances), then verify
7410 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7411 -- the same subtype chain. The whole purpose of this procedure is to
7412 -- prevent spurious ambiguities in an instantiation that may arise if
7413 -- two distinct generic types are instantiated with the same actual.
7415 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7416 -- An access parameter can designate an incomplete type. If the
7417 -- incomplete type is the limited view of a type from a limited_
7418 -- with_clause, check whether the non-limited view is available.
7419 -- If it is a (non-limited) incomplete type, get the full view.
7421 function Matches_Limited_With_View
7423 Typ_2 : Entity_Id) return Boolean;
7424 -- Returns True if and only if either Typ_1 denotes a limited view of
7425 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7426 -- the limited with view of a type is used in a subprogram declaration
7427 -- and the subprogram body is in the scope of a regular with clause for
7428 -- the same unit. In such a case, the two type entities are considered
7429 -- identical for purposes of conformance checking.
7431 ----------------------
7432 -- Base_Types_Match --
7433 ----------------------
7435 function Base_Types_Match
7437 Typ_2 : Entity_Id) return Boolean
7439 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7440 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7443 if Typ_1 = Typ_2 then
7446 elsif Base_1 = Base_2 then
7448 -- The following is too permissive. A more precise test should
7449 -- check that the generic actual is an ancestor subtype of the
7452 -- See code in Find_Corresponding_Spec that applies an additional
7453 -- filter to handle accidental amiguities in instances.
7456 not Is_Generic_Actual_Type (Typ_1)
7457 or else not Is_Generic_Actual_Type (Typ_2)
7458 or else Scope (Typ_1) /= Scope (Typ_2);
7460 -- If Typ_2 is a generic actual type it is declared as the subtype of
7461 -- the actual. If that actual is itself a subtype we need to use its
7462 -- own base type to check for compatibility.
7464 elsif Ekind (Base_2) = Ekind (Typ_2)
7465 and then Base_1 = Base_Type (Base_2)
7469 elsif Ekind (Base_1) = Ekind (Typ_1)
7470 and then Base_2 = Base_Type (Base_1)
7477 end Base_Types_Match;
7479 --------------------------
7480 -- Find_Designated_Type --
7481 --------------------------
7483 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7487 Desig := Directly_Designated_Type (Typ);
7489 if Ekind (Desig) = E_Incomplete_Type then
7491 -- If regular incomplete type, get full view if available
7493 if Present (Full_View (Desig)) then
7494 Desig := Full_View (Desig);
7496 -- If limited view of a type, get non-limited view if available,
7497 -- and check again for a regular incomplete type.
7499 elsif Present (Non_Limited_View (Desig)) then
7500 Desig := Get_Full_View (Non_Limited_View (Desig));
7505 end Find_Designated_Type;
7507 -------------------------------
7508 -- Matches_Limited_With_View --
7509 -------------------------------
7511 function Matches_Limited_With_View
7513 Typ_2 : Entity_Id) return Boolean
7515 function Is_Matching_Limited_View
7517 View : Entity_Id) return Boolean;
7518 -- Determine whether non-limited view View denotes type Typ in some
7519 -- conformant fashion.
7521 ------------------------------
7522 -- Is_Matching_Limited_View --
7523 ------------------------------
7525 function Is_Matching_Limited_View
7527 View : Entity_Id) return Boolean
7529 Root_Typ : Entity_Id;
7530 Root_View : Entity_Id;
7533 -- The non-limited view directly denotes the type
7538 -- The type is a subtype of the non-limited view
7540 elsif Is_Subtype_Of (Typ, View) then
7543 -- Both the non-limited view and the type denote class-wide types
7545 elsif Is_Class_Wide_Type (Typ)
7546 and then Is_Class_Wide_Type (View)
7548 Root_Typ := Root_Type (Typ);
7549 Root_View := Root_Type (View);
7551 if Root_Typ = Root_View then
7554 -- An incomplete tagged type and its full view may receive two
7555 -- distinct class-wide types when the related package has not
7556 -- been analyzed yet.
7559 -- type T is tagged; -- CW_1
7560 -- type T is tagged null record; -- CW_2
7563 -- This is because the package lacks any semantic information
7564 -- that may eventually link both views of T. As a consequence,
7565 -- a client of the limited view of Pack will see CW_2 while a
7566 -- client of the non-limited view of Pack will see CW_1.
7568 elsif Is_Incomplete_Type (Root_Typ)
7569 and then Present (Full_View (Root_Typ))
7570 and then Full_View (Root_Typ) = Root_View
7574 elsif Is_Incomplete_Type (Root_View)
7575 and then Present (Full_View (Root_View))
7576 and then Full_View (Root_View) = Root_Typ
7583 end Is_Matching_Limited_View;
7585 -- Start of processing for Matches_Limited_With_View
7588 -- In some cases a type imported through a limited_with clause, and
7589 -- its non-limited view are both visible, for example in an anonymous
7590 -- access-to-class-wide type in a formal, or when building the body
7591 -- for a subprogram renaming after the subprogram has been frozen.
7592 -- In these cases both entities designate the same type. In addition,
7593 -- if one of them is an actual in an instance, it may be a subtype of
7594 -- the non-limited view of the other.
7596 if From_Limited_With (Typ_1)
7597 and then From_Limited_With (Typ_2)
7598 and then Available_View (Typ_1) = Available_View (Typ_2)
7602 elsif From_Limited_With (Typ_1) then
7603 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7605 elsif From_Limited_With (Typ_2) then
7606 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7611 end Matches_Limited_With_View;
7615 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7617 Type_1 : Entity_Id := T1;
7618 Type_2 : Entity_Id := T2;
7620 -- Start of processing for Conforming_Types
7623 -- The context is an instance association for a formal access-to-
7624 -- subprogram type; the formal parameter types require mapping because
7625 -- they may denote other formal parameters of the generic unit.
7628 Type_1 := Get_Instance_Of (T1);
7629 Type_2 := Get_Instance_Of (T2);
7632 -- If one of the types is a view of the other introduced by a limited
7633 -- with clause, treat these as conforming for all purposes.
7635 if Matches_Limited_With_View (T1, T2) then
7638 elsif Base_Types_Match (Type_1, Type_2) then
7639 if Ctype <= Mode_Conformant then
7644 Subtypes_Statically_Match (Type_1, Type_2)
7645 and then Dimensions_Match (Type_1, Type_2);
7648 elsif Is_Incomplete_Or_Private_Type (Type_1)
7649 and then Present (Full_View (Type_1))
7650 and then Base_Types_Match (Full_View (Type_1), Type_2)
7653 Ctype <= Mode_Conformant
7654 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7656 elsif Ekind (Type_2) = E_Incomplete_Type
7657 and then Present (Full_View (Type_2))
7658 and then Base_Types_Match (Type_1, Full_View (Type_2))
7661 Ctype <= Mode_Conformant
7662 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7664 elsif Is_Private_Type (Type_2)
7665 and then In_Instance
7666 and then Present (Full_View (Type_2))
7667 and then Base_Types_Match (Type_1, Full_View (Type_2))
7670 Ctype <= Mode_Conformant
7671 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7673 -- Another confusion between views in a nested instance with an
7674 -- actual private type whose full view is not in scope.
7676 elsif Ekind (Type_2) = E_Private_Subtype
7677 and then In_Instance
7678 and then Etype (Type_2) = Type_1
7682 -- In Ada 2012, incomplete types (including limited views) can appear
7683 -- as actuals in instantiations, where they are conformant to the
7684 -- corresponding incomplete formal.
7686 elsif Is_Incomplete_Type (Type_1)
7687 and then Is_Incomplete_Type (Type_2)
7688 and then In_Instance
7689 and then (Used_As_Generic_Actual (Type_1)
7690 or else Used_As_Generic_Actual (Type_2))
7695 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7696 -- treated recursively because they carry a signature. As far as
7697 -- conformance is concerned, convention plays no role, and either
7698 -- or both could be access to protected subprograms.
7700 Are_Anonymous_Access_To_Subprogram_Types :=
7701 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7702 E_Anonymous_Access_Protected_Subprogram_Type)
7704 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7705 E_Anonymous_Access_Protected_Subprogram_Type);
7707 -- Test anonymous access type case. For this case, static subtype
7708 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7709 -- the base types because we may have built internal subtype entities
7710 -- to handle null-excluding types (see Process_Formals).
7712 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7714 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7716 -- Ada 2005 (AI-254)
7718 or else Are_Anonymous_Access_To_Subprogram_Types
7721 Desig_1 : Entity_Id;
7722 Desig_2 : Entity_Id;
7725 -- In Ada 2005, access constant indicators must match for
7726 -- subtype conformance.
7728 if Ada_Version >= Ada_2005
7729 and then Ctype >= Subtype_Conformant
7731 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7736 Desig_1 := Find_Designated_Type (Type_1);
7737 Desig_2 := Find_Designated_Type (Type_2);
7739 -- If the context is an instance association for a formal
7740 -- access-to-subprogram type; formal access parameter designated
7741 -- types require mapping because they may denote other formal
7742 -- parameters of the generic unit.
7745 Desig_1 := Get_Instance_Of (Desig_1);
7746 Desig_2 := Get_Instance_Of (Desig_2);
7749 -- It is possible for a Class_Wide_Type to be introduced for an
7750 -- incomplete type, in which case there is a separate class_ wide
7751 -- type for the full view. The types conform if their Etypes
7752 -- conform, i.e. one may be the full view of the other. This can
7753 -- only happen in the context of an access parameter, other uses
7754 -- of an incomplete Class_Wide_Type are illegal.
7756 if Is_Class_Wide_Type (Desig_1)
7758 Is_Class_Wide_Type (Desig_2)
7762 (Etype (Base_Type (Desig_1)),
7763 Etype (Base_Type (Desig_2)), Ctype);
7765 elsif Are_Anonymous_Access_To_Subprogram_Types then
7766 if Ada_Version < Ada_2005 then
7768 Ctype = Type_Conformant
7769 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7771 -- We must check the conformance of the signatures themselves
7775 Conformant : Boolean;
7778 (Desig_1, Desig_2, Ctype, False, Conformant);
7783 -- A limited view of an actual matches the corresponding
7784 -- incomplete formal.
7786 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7787 and then From_Limited_With (Desig_2)
7788 and then Used_As_Generic_Actual (Etype (Desig_2))
7793 return Base_Type (Desig_1) = Base_Type (Desig_2)
7794 and then (Ctype = Type_Conformant
7796 Subtypes_Statically_Match (Desig_1, Desig_2));
7800 -- Otherwise definitely no match
7803 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7804 and then Is_Access_Type (Type_2))
7805 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7806 and then Is_Access_Type (Type_1)))
7809 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7811 May_Hide_Profile := True;
7816 end Conforming_Types;
7818 --------------------------
7819 -- Create_Extra_Formals --
7820 --------------------------
7822 procedure Create_Extra_Formals (E : Entity_Id) is
7823 First_Extra : Entity_Id := Empty;
7825 Last_Extra : Entity_Id := Empty;
7827 function Add_Extra_Formal
7828 (Assoc_Entity : Entity_Id;
7831 Suffix : String) return Entity_Id;
7832 -- Add an extra formal to the current list of formals and extra formals.
7833 -- The extra formal is added to the end of the list of extra formals,
7834 -- and also returned as the result. These formals are always of mode IN.
7835 -- The new formal has the type Typ, is declared in Scope, and its name
7836 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7837 -- The following suffixes are currently used. They should not be changed
7838 -- without coordinating with CodePeer, which makes use of these to
7839 -- provide better messages.
7841 -- O denotes the Constrained bit.
7842 -- L denotes the accessibility level.
7843 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7844 -- the full list in exp_ch6.BIP_Formal_Kind.
7846 ----------------------
7847 -- Add_Extra_Formal --
7848 ----------------------
7850 function Add_Extra_Formal
7851 (Assoc_Entity : Entity_Id;
7854 Suffix : String) return Entity_Id
7856 EF : constant Entity_Id :=
7857 Make_Defining_Identifier (Sloc (Assoc_Entity),
7858 Chars => New_External_Name (Chars (Assoc_Entity),
7862 -- A little optimization. Never generate an extra formal for the
7863 -- _init operand of an initialization procedure, since it could
7866 if Chars (Formal) = Name_uInit then
7870 Set_Ekind (EF, E_In_Parameter);
7871 Set_Actual_Subtype (EF, Typ);
7872 Set_Etype (EF, Typ);
7873 Set_Scope (EF, Scope);
7874 Set_Mechanism (EF, Default_Mechanism);
7875 Set_Formal_Validity (EF);
7877 if No (First_Extra) then
7879 Set_Extra_Formals (Scope, EF);
7882 if Present (Last_Extra) then
7883 Set_Extra_Formal (Last_Extra, EF);
7889 end Add_Extra_Formal;
7893 Formal_Type : Entity_Id;
7894 P_Formal : Entity_Id := Empty;
7896 -- Start of processing for Create_Extra_Formals
7899 -- We never generate extra formals if expansion is not active because we
7900 -- don't need them unless we are generating code.
7902 if not Expander_Active then
7906 -- No need to generate extra formals in interface thunks whose target
7907 -- primitive has no extra formals.
7909 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7913 -- If this is a derived subprogram then the subtypes of the parent
7914 -- subprogram's formal parameters will be used to determine the need
7915 -- for extra formals.
7917 if Is_Overloadable (E) and then Present (Alias (E)) then
7918 P_Formal := First_Formal (Alias (E));
7921 Formal := First_Formal (E);
7922 while Present (Formal) loop
7923 Last_Extra := Formal;
7924 Next_Formal (Formal);
7927 -- If Extra_Formals were already created, don't do it again. This
7928 -- situation may arise for subprogram types created as part of
7929 -- dispatching calls (see Expand_Dispatching_Call).
7931 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7935 -- If the subprogram is a predefined dispatching subprogram then don't
7936 -- generate any extra constrained or accessibility level formals. In
7937 -- general we suppress these for internal subprograms (by not calling
7938 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7939 -- generated stream attributes do get passed through because extra
7940 -- build-in-place formals are needed in some cases (limited 'Input).
7942 if Is_Predefined_Internal_Operation (E) then
7943 goto Test_For_Func_Result_Extras;
7946 Formal := First_Formal (E);
7947 while Present (Formal) loop
7949 -- Create extra formal for supporting the attribute 'Constrained.
7950 -- The case of a private type view without discriminants also
7951 -- requires the extra formal if the underlying type has defaulted
7954 if Ekind (Formal) /= E_In_Parameter then
7955 if Present (P_Formal) then
7956 Formal_Type := Etype (P_Formal);
7958 Formal_Type := Etype (Formal);
7961 -- Do not produce extra formals for Unchecked_Union parameters.
7962 -- Jump directly to the end of the loop.
7964 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7965 goto Skip_Extra_Formal_Generation;
7968 if not Has_Discriminants (Formal_Type)
7969 and then Ekind (Formal_Type) in Private_Kind
7970 and then Present (Underlying_Type (Formal_Type))
7972 Formal_Type := Underlying_Type (Formal_Type);
7975 -- Suppress the extra formal if formal's subtype is constrained or
7976 -- indefinite, or we're compiling for Ada 2012 and the underlying
7977 -- type is tagged and limited. In Ada 2012, a limited tagged type
7978 -- can have defaulted discriminants, but 'Constrained is required
7979 -- to return True, so the formal is never needed (see AI05-0214).
7980 -- Note that this ensures consistency of calling sequences for
7981 -- dispatching operations when some types in a class have defaults
7982 -- on discriminants and others do not (and requiring the extra
7983 -- formal would introduce distributed overhead).
7985 -- If the type does not have a completion yet, treat as prior to
7986 -- Ada 2012 for consistency.
7988 if Has_Discriminants (Formal_Type)
7989 and then not Is_Constrained (Formal_Type)
7990 and then Is_Definite_Subtype (Formal_Type)
7991 and then (Ada_Version < Ada_2012
7992 or else No (Underlying_Type (Formal_Type))
7994 (Is_Limited_Type (Formal_Type)
7997 (Underlying_Type (Formal_Type)))))
7999 Set_Extra_Constrained
8000 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8004 -- Create extra formal for supporting accessibility checking. This
8005 -- is done for both anonymous access formals and formals of named
8006 -- access types that are marked as controlling formals. The latter
8007 -- case can occur when Expand_Dispatching_Call creates a subprogram
8008 -- type and substitutes the types of access-to-class-wide actuals
8009 -- for the anonymous access-to-specific-type of controlling formals.
8010 -- Base_Type is applied because in cases where there is a null
8011 -- exclusion the formal may have an access subtype.
8013 -- This is suppressed if we specifically suppress accessibility
8014 -- checks at the package level for either the subprogram, or the
8015 -- package in which it resides. However, we do not suppress it
8016 -- simply if the scope has accessibility checks suppressed, since
8017 -- this could cause trouble when clients are compiled with a
8018 -- different suppression setting. The explicit checks at the
8019 -- package level are safe from this point of view.
8021 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8022 or else (Is_Controlling_Formal (Formal)
8023 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8025 (Explicit_Suppress (E, Accessibility_Check)
8027 Explicit_Suppress (Scope (E), Accessibility_Check))
8030 or else Present (Extra_Accessibility (P_Formal)))
8032 Set_Extra_Accessibility
8033 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8036 -- This label is required when skipping extra formal generation for
8037 -- Unchecked_Union parameters.
8039 <<Skip_Extra_Formal_Generation>>
8041 if Present (P_Formal) then
8042 Next_Formal (P_Formal);
8045 Next_Formal (Formal);
8048 <<Test_For_Func_Result_Extras>>
8050 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8051 -- function call is ... determined by the point of call ...".
8053 if Needs_Result_Accessibility_Level (E) then
8054 Set_Extra_Accessibility_Of_Result
8055 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8058 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8059 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8061 if Is_Build_In_Place_Function (E) then
8063 Result_Subt : constant Entity_Id := Etype (E);
8064 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8065 Formal_Typ : Entity_Id;
8066 Subp_Decl : Node_Id;
8067 Discard : Entity_Id;
8070 -- In the case of functions with unconstrained result subtypes,
8071 -- add a 4-state formal indicating whether the return object is
8072 -- allocated by the caller (1), or should be allocated by the
8073 -- callee on the secondary stack (2), in the global heap (3), or
8074 -- in a user-defined storage pool (4). For the moment we just use
8075 -- Natural for the type of this formal. Note that this formal
8076 -- isn't usually needed in the case where the result subtype is
8077 -- constrained, but it is needed when the function has a tagged
8078 -- result, because generally such functions can be called in a
8079 -- dispatching context and such calls must be handled like calls
8080 -- to a class-wide function.
8082 if Needs_BIP_Alloc_Form (E) then
8085 (E, Standard_Natural,
8086 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8088 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8089 -- use a user-defined pool. This formal is not added on
8090 -- ZFP as those targets do not support pools.
8092 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8095 (E, RTE (RE_Root_Storage_Pool_Ptr),
8096 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8100 -- In the case of functions whose result type needs finalization,
8101 -- add an extra formal which represents the finalization master.
8103 if Needs_BIP_Finalization_Master (E) then
8106 (E, RTE (RE_Finalization_Master_Ptr),
8107 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8110 -- When the result type contains tasks, add two extra formals: the
8111 -- master of the tasks to be created, and the caller's activation
8114 if Has_Task (Full_Subt) then
8117 (E, RTE (RE_Master_Id),
8118 E, BIP_Formal_Suffix (BIP_Task_Master));
8121 (E, RTE (RE_Activation_Chain_Access),
8122 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8125 -- All build-in-place functions get an extra formal that will be
8126 -- passed the address of the return object within the caller.
8129 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8131 -- Incomplete_View_From_Limited_With is needed here because
8132 -- gigi gets confused if the designated type is the full view
8133 -- coming from a limited-with'ed package. In the normal case,
8134 -- (no limited with) Incomplete_View_From_Limited_With
8135 -- returns Result_Subt.
8137 Set_Directly_Designated_Type
8138 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8139 Set_Etype (Formal_Typ, Formal_Typ);
8140 Set_Depends_On_Private
8141 (Formal_Typ, Has_Private_Component (Formal_Typ));
8142 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8143 Set_Is_Access_Constant (Formal_Typ, False);
8145 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8146 -- the designated type comes from the limited view (for back-end
8149 Set_From_Limited_With
8150 (Formal_Typ, From_Limited_With (Result_Subt));
8152 Layout_Type (Formal_Typ);
8154 -- Force the definition of the Itype in case of internal function
8155 -- calls within the same or nested scope.
8157 if Is_Subprogram_Or_Generic_Subprogram (E) then
8158 Subp_Decl := Parent (E);
8160 -- The insertion point for an Itype reference should be after
8161 -- the unit declaration node of the subprogram. An exception
8162 -- to this are inherited operations from a parent type in which
8163 -- case the derived type acts as their parent.
8165 if Nkind_In (Subp_Decl, N_Function_Specification,
8166 N_Procedure_Specification)
8168 Subp_Decl := Parent (Subp_Decl);
8171 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8176 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8180 -- If this is an instance of a generic, we need to have extra formals
8183 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8184 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8186 end Create_Extra_Formals;
8188 -----------------------------
8189 -- Enter_Overloaded_Entity --
8190 -----------------------------
8192 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8193 function Matches_Predefined_Op return Boolean;
8194 -- This returns an approximation of whether S matches a predefined
8195 -- operator, based on the operator symbol, and the parameter and result
8196 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8198 ---------------------------
8199 -- Matches_Predefined_Op --
8200 ---------------------------
8202 function Matches_Predefined_Op return Boolean is
8203 Formal_1 : constant Entity_Id := First_Formal (S);
8204 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8205 Op : constant Name_Id := Chars (S);
8206 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8207 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8212 if Present (Formal_2) then
8214 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8217 -- All but "&" and "**" have same-types parameters
8226 if Type_1 /= Type_2 then
8231 -- Check parameter and result types
8239 Is_Boolean_Type (Result_Type)
8240 and then Result_Type = Type_1;
8246 Is_Integer_Type (Result_Type)
8247 and then Result_Type = Type_1;
8255 Is_Numeric_Type (Result_Type)
8256 and then Result_Type = Type_1;
8262 Is_Boolean_Type (Result_Type)
8263 and then not Is_Limited_Type (Type_1);
8271 Is_Boolean_Type (Result_Type)
8272 and then (Is_Array_Type (Type_1)
8273 or else Is_Scalar_Type (Type_1));
8275 when Name_Op_Concat =>
8276 return Is_Array_Type (Result_Type);
8278 when Name_Op_Expon =>
8280 (Is_Integer_Type (Result_Type)
8281 or else Is_Floating_Point_Type (Result_Type))
8282 and then Result_Type = Type_1
8283 and then Type_2 = Standard_Integer;
8286 raise Program_Error;
8299 Is_Numeric_Type (Result_Type)
8300 and then Result_Type = Type_1;
8304 Is_Boolean_Type (Result_Type)
8305 and then Result_Type = Type_1;
8308 raise Program_Error;
8311 end Matches_Predefined_Op;
8315 E : Entity_Id := Current_Entity_In_Scope (S);
8316 C_E : Entity_Id := Current_Entity (S);
8318 -- Start of processing for Enter_Overloaded_Entity
8322 Set_Has_Homonym (E);
8323 Set_Has_Homonym (S);
8326 Set_Is_Immediately_Visible (S);
8327 Set_Scope (S, Current_Scope);
8329 -- Chain new entity if front of homonym in current scope, so that
8330 -- homonyms are contiguous.
8332 if Present (E) and then E /= C_E then
8333 while Homonym (C_E) /= E loop
8334 C_E := Homonym (C_E);
8337 Set_Homonym (C_E, S);
8341 Set_Current_Entity (S);
8346 if Is_Inherited_Operation (S) then
8347 Append_Inherited_Subprogram (S);
8349 Append_Entity (S, Current_Scope);
8352 Set_Public_Status (S);
8354 if Debug_Flag_E then
8355 Write_Str ("New overloaded entity chain: ");
8356 Write_Name (Chars (S));
8359 while Present (E) loop
8360 Write_Str (" "); Write_Int (Int (E));
8367 -- Generate warning for hiding
8370 and then Comes_From_Source (S)
8371 and then In_Extended_Main_Source_Unit (S)
8378 -- Warn unless genuine overloading. Do not emit warning on
8379 -- hiding predefined operators in Standard (these are either an
8380 -- (artifact of our implicit declarations, or simple noise) but
8381 -- keep warning on a operator defined on a local subtype, because
8382 -- of the real danger that different operators may be applied in
8383 -- various parts of the program.
8385 -- Note that if E and S have the same scope, there is never any
8386 -- hiding. Either the two conflict, and the program is illegal,
8387 -- or S is overriding an implicit inherited subprogram.
8389 if Scope (E) /= Scope (S)
8390 and then (not Is_Overloadable (E)
8391 or else Subtype_Conformant (E, S))
8392 and then (Is_Immediately_Visible (E)
8393 or else Is_Potentially_Use_Visible (S))
8395 if Scope (E) = Standard_Standard then
8396 if Nkind (S) = N_Defining_Operator_Symbol
8397 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8399 and then Matches_Predefined_Op
8402 ("declaration of & hides predefined operator?h?", S);
8405 -- E not immediately within Standard
8408 Error_Msg_Sloc := Sloc (E);
8409 Error_Msg_N ("declaration of & hides one #?h?", S);
8414 end Enter_Overloaded_Entity;
8416 -----------------------------
8417 -- Check_Untagged_Equality --
8418 -----------------------------
8420 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8421 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8422 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8426 -- This check applies only if we have a subprogram declaration with an
8427 -- untagged record type.
8429 if Nkind (Decl) /= N_Subprogram_Declaration
8430 or else not Is_Record_Type (Typ)
8431 or else Is_Tagged_Type (Typ)
8436 -- In Ada 2012 case, we will output errors or warnings depending on
8437 -- the setting of debug flag -gnatd.E.
8439 if Ada_Version >= Ada_2012 then
8440 Error_Msg_Warn := Debug_Flag_Dot_EE;
8442 -- In earlier versions of Ada, nothing to do unless we are warning on
8443 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8446 if not Warn_On_Ada_2012_Compatibility then
8451 -- Cases where the type has already been frozen
8453 if Is_Frozen (Typ) then
8455 -- If the type is not declared in a package, or if we are in the body
8456 -- of the package or in some other scope, the new operation is not
8457 -- primitive, and therefore legal, though suspicious. Should we
8458 -- generate a warning in this case ???
8460 if Ekind (Scope (Typ)) /= E_Package
8461 or else Scope (Typ) /= Current_Scope
8465 -- If the type is a generic actual (sub)type, the operation is not
8466 -- primitive either because the base type is declared elsewhere.
8468 elsif Is_Generic_Actual_Type (Typ) then
8471 -- Here we have a definite error of declaration after freezing
8474 if Ada_Version >= Ada_2012 then
8476 ("equality operator must be declared before type & is "
8477 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8479 -- In Ada 2012 mode with error turned to warning, output one
8480 -- more warning to warn that the equality operation may not
8481 -- compose. This is the consequence of ignoring the error.
8483 if Error_Msg_Warn then
8484 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8489 ("equality operator must be declared before type& is "
8490 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8493 -- If we are in the package body, we could just move the
8494 -- declaration to the package spec, so add a message saying that.
8496 if In_Package_Body (Scope (Typ)) then
8497 if Ada_Version >= Ada_2012 then
8499 ("\move declaration to package spec<<", Eq_Op);
8502 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8505 -- Otherwise try to find the freezing point
8508 Obj_Decl := Next (Parent (Typ));
8509 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8510 if Nkind (Obj_Decl) = N_Object_Declaration
8511 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8513 -- Freezing point, output warnings
8515 if Ada_Version >= Ada_2012 then
8517 ("type& is frozen by declaration??", Obj_Decl, Typ);
8519 ("\an equality operator cannot be declared after "
8524 ("type& is frozen by declaration (Ada 2012)?y?",
8527 ("\an equality operator cannot be declared after "
8528 & "this point (Ada 2012)?y?",
8540 -- Here if type is not frozen yet. It is illegal to have a primitive
8541 -- equality declared in the private part if the type is visible.
8543 elsif not In_Same_List (Parent (Typ), Decl)
8544 and then not Is_Limited_Type (Typ)
8546 -- Shouldn't we give an RM reference here???
8548 if Ada_Version >= Ada_2012 then
8550 ("equality operator appears too late<<", Eq_Op);
8553 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8556 -- No error detected
8561 end Check_Untagged_Equality;
8563 -----------------------------
8564 -- Find_Corresponding_Spec --
8565 -----------------------------
8567 function Find_Corresponding_Spec
8569 Post_Error : Boolean := True) return Entity_Id
8571 Spec : constant Node_Id := Specification (N);
8572 Designator : constant Entity_Id := Defining_Entity (Spec);
8576 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8577 -- Even if fully conformant, a body may depend on a generic actual when
8578 -- the spec does not, or vice versa, in which case they were distinct
8579 -- entities in the generic.
8581 -------------------------------
8582 -- Different_Generic_Profile --
8583 -------------------------------
8585 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8588 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8589 -- Check that the types of corresponding formals have the same
8590 -- generic actual if any. We have to account for subtypes of a
8591 -- generic formal, declared between a spec and a body, which may
8592 -- appear distinct in an instance but matched in the generic, and
8593 -- the subtype may be used either in the spec or the body of the
8594 -- subprogram being checked.
8596 -------------------------
8597 -- Same_Generic_Actual --
8598 -------------------------
8600 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8602 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8603 -- Predicate to check whether S1 is a subtype of S2 in the source
8606 -------------------------
8607 -- Is_Declared_Subtype --
8608 -------------------------
8610 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8612 return Comes_From_Source (Parent (S1))
8613 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8614 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8615 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8616 end Is_Declared_Subtype;
8618 -- Start of processing for Same_Generic_Actual
8621 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8622 or else Is_Declared_Subtype (T1, T2)
8623 or else Is_Declared_Subtype (T2, T1);
8624 end Same_Generic_Actual;
8626 -- Start of processing for Different_Generic_Profile
8629 if not In_Instance then
8632 elsif Ekind (E) = E_Function
8633 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8638 F1 := First_Formal (Designator);
8639 F2 := First_Formal (E);
8640 while Present (F1) loop
8641 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8650 end Different_Generic_Profile;
8652 -- Start of processing for Find_Corresponding_Spec
8655 E := Current_Entity (Designator);
8656 while Present (E) loop
8658 -- We are looking for a matching spec. It must have the same scope,
8659 -- and the same name, and either be type conformant, or be the case
8660 -- of a library procedure spec and its body (which belong to one
8661 -- another regardless of whether they are type conformant or not).
8663 if Scope (E) = Current_Scope then
8664 if Current_Scope = Standard_Standard
8665 or else (Ekind (E) = Ekind (Designator)
8666 and then Type_Conformant (E, Designator))
8668 -- Within an instantiation, we know that spec and body are
8669 -- subtype conformant, because they were subtype conformant in
8670 -- the generic. We choose the subtype-conformant entity here as
8671 -- well, to resolve spurious ambiguities in the instance that
8672 -- were not present in the generic (i.e. when two different
8673 -- types are given the same actual). If we are looking for a
8674 -- spec to match a body, full conformance is expected.
8678 -- Inherit the convention and "ghostness" of the matching
8679 -- spec to ensure proper full and subtype conformance.
8681 Set_Convention (Designator, Convention (E));
8683 -- Skip past subprogram bodies and subprogram renamings that
8684 -- may appear to have a matching spec, but that aren't fully
8685 -- conformant with it. That can occur in cases where an
8686 -- actual type causes unrelated homographs in the instance.
8688 if Nkind_In (N, N_Subprogram_Body,
8689 N_Subprogram_Renaming_Declaration)
8690 and then Present (Homonym (E))
8691 and then not Fully_Conformant (Designator, E)
8695 elsif not Subtype_Conformant (Designator, E) then
8698 elsif Different_Generic_Profile (E) then
8703 -- Ada 2012 (AI05-0165): For internally generated bodies of
8704 -- null procedures locate the internally generated spec. We
8705 -- enforce mode conformance since a tagged type may inherit
8706 -- from interfaces several null primitives which differ only
8707 -- in the mode of the formals.
8709 if not (Comes_From_Source (E))
8710 and then Is_Null_Procedure (E)
8711 and then not Mode_Conformant (Designator, E)
8715 -- For null procedures coming from source that are completions,
8716 -- analysis of the generated body will establish the link.
8718 elsif Comes_From_Source (E)
8719 and then Nkind (Spec) = N_Procedure_Specification
8720 and then Null_Present (Spec)
8724 -- Expression functions can be completions, but cannot be
8725 -- completed by an explicit body.
8727 elsif Comes_From_Source (E)
8728 and then Comes_From_Source (N)
8729 and then Nkind (N) = N_Subprogram_Body
8730 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8731 N_Expression_Function
8733 Error_Msg_Sloc := Sloc (E);
8734 Error_Msg_N ("body conflicts with expression function#", N);
8737 elsif not Has_Completion (E) then
8738 if Nkind (N) /= N_Subprogram_Body_Stub then
8739 Set_Corresponding_Spec (N, E);
8742 Set_Has_Completion (E);
8745 elsif Nkind (Parent (N)) = N_Subunit then
8747 -- If this is the proper body of a subunit, the completion
8748 -- flag is set when analyzing the stub.
8752 -- If E is an internal function with a controlling result that
8753 -- was created for an operation inherited by a null extension,
8754 -- it may be overridden by a body without a previous spec (one
8755 -- more reason why these should be shunned). In that case we
8756 -- remove the generated body if present, because the current
8757 -- one is the explicit overriding.
8759 elsif Ekind (E) = E_Function
8760 and then Ada_Version >= Ada_2005
8761 and then not Comes_From_Source (E)
8762 and then Has_Controlling_Result (E)
8763 and then Is_Null_Extension (Etype (E))
8764 and then Comes_From_Source (Spec)
8766 Set_Has_Completion (E, False);
8769 and then Nkind (Parent (E)) = N_Function_Specification
8772 (Unit_Declaration_Node
8773 (Corresponding_Body (Unit_Declaration_Node (E))));
8777 -- If expansion is disabled, or if the wrapper function has
8778 -- not been generated yet, this a late body overriding an
8779 -- inherited operation, or it is an overriding by some other
8780 -- declaration before the controlling result is frozen. In
8781 -- either case this is a declaration of a new entity.
8787 -- If the body already exists, then this is an error unless
8788 -- the previous declaration is the implicit declaration of a
8789 -- derived subprogram. It is also legal for an instance to
8790 -- contain type conformant overloadable declarations (but the
8791 -- generic declaration may not), per 8.3(26/2).
8793 elsif No (Alias (E))
8794 and then not Is_Intrinsic_Subprogram (E)
8795 and then not In_Instance
8798 Error_Msg_Sloc := Sloc (E);
8800 if Is_Imported (E) then
8802 ("body not allowed for imported subprogram & declared#",
8805 Error_Msg_NE ("duplicate body for & declared#", N, E);
8809 -- Child units cannot be overloaded, so a conformance mismatch
8810 -- between body and a previous spec is an error.
8812 elsif Is_Child_Unit (E)
8814 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8816 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8821 ("body of child unit does not match previous declaration", N);
8829 -- On exit, we know that no previous declaration of subprogram exists
8832 end Find_Corresponding_Spec;
8834 ----------------------
8835 -- Fully_Conformant --
8836 ----------------------
8838 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8841 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8843 end Fully_Conformant;
8845 ----------------------------------
8846 -- Fully_Conformant_Expressions --
8847 ----------------------------------
8849 function Fully_Conformant_Expressions
8850 (Given_E1 : Node_Id;
8851 Given_E2 : Node_Id) return Boolean
8853 E1 : constant Node_Id := Original_Node (Given_E1);
8854 E2 : constant Node_Id := Original_Node (Given_E2);
8855 -- We always test conformance on original nodes, since it is possible
8856 -- for analysis and/or expansion to make things look as though they
8857 -- conform when they do not, e.g. by converting 1+2 into 3.
8859 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8860 renames Fully_Conformant_Expressions;
8862 function FCL (L1, L2 : List_Id) return Boolean;
8863 -- Compare elements of two lists for conformance. Elements have to be
8864 -- conformant, and actuals inserted as default parameters do not match
8865 -- explicit actuals with the same value.
8867 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8868 -- Compare an operator node with a function call
8874 function FCL (L1, L2 : List_Id) return Boolean is
8878 if L1 = No_List then
8884 if L2 = No_List then
8890 -- Compare two lists, skipping rewrite insertions (we want to compare
8891 -- the original trees, not the expanded versions).
8894 if Is_Rewrite_Insertion (N1) then
8896 elsif Is_Rewrite_Insertion (N2) then
8902 elsif not FCE (N1, N2) then
8915 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8916 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8921 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8926 Act := First (Actuals);
8928 if Nkind (Op_Node) in N_Binary_Op then
8929 if not FCE (Left_Opnd (Op_Node), Act) then
8936 return Present (Act)
8937 and then FCE (Right_Opnd (Op_Node), Act)
8938 and then No (Next (Act));
8942 -- Start of processing for Fully_Conformant_Expressions
8945 -- Nonconformant if paren count does not match. Note: if some idiot
8946 -- complains that we don't do this right for more than 3 levels of
8947 -- parentheses, they will be treated with the respect they deserve.
8949 if Paren_Count (E1) /= Paren_Count (E2) then
8952 -- If same entities are referenced, then they are conformant even if
8953 -- they have different forms (RM 8.3.1(19-20)).
8955 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8956 if Present (Entity (E1)) then
8957 return Entity (E1) = Entity (E2)
8959 -- One may be a discriminant that has been replaced by the
8960 -- corresponding discriminal.
8963 (Chars (Entity (E1)) = Chars (Entity (E2))
8964 and then Ekind (Entity (E1)) = E_Discriminant
8965 and then Ekind (Entity (E2)) = E_In_Parameter)
8967 -- The discriminant of a protected type is transformed into
8968 -- a local constant and then into a parameter of a protected
8972 (Ekind (Entity (E1)) = E_Constant
8973 and then Ekind (Entity (E2)) = E_In_Parameter
8974 and then Present (Discriminal_Link (Entity (E1)))
8975 and then Discriminal_Link (Entity (E1)) =
8976 Discriminal_Link (Entity (E2)))
8978 -- AI12-050: The loop variables of quantified expressions
8979 -- match if they have the same identifier, even though they
8980 -- are different entities.
8983 (Chars (Entity (E1)) = Chars (Entity (E2))
8984 and then Ekind (Entity (E1)) = E_Loop_Parameter
8985 and then Ekind (Entity (E2)) = E_Loop_Parameter);
8987 elsif Nkind (E1) = N_Expanded_Name
8988 and then Nkind (E2) = N_Expanded_Name
8989 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8990 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8992 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8995 -- Identifiers in component associations don't always have
8996 -- entities, but their names must conform.
8998 return Nkind (E1) = N_Identifier
8999 and then Nkind (E2) = N_Identifier
9000 and then Chars (E1) = Chars (E2);
9003 elsif Nkind (E1) = N_Character_Literal
9004 and then Nkind (E2) = N_Expanded_Name
9006 return Nkind (Selector_Name (E2)) = N_Character_Literal
9007 and then Chars (E1) = Chars (Selector_Name (E2));
9009 elsif Nkind (E2) = N_Character_Literal
9010 and then Nkind (E1) = N_Expanded_Name
9012 return Nkind (Selector_Name (E1)) = N_Character_Literal
9013 and then Chars (E2) = Chars (Selector_Name (E1));
9015 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9016 return FCO (E1, E2);
9018 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9019 return FCO (E2, E1);
9021 -- Otherwise we must have the same syntactic entity
9023 elsif Nkind (E1) /= Nkind (E2) then
9026 -- At this point, we specialize by node type
9032 FCL (Expressions (E1), Expressions (E2))
9034 FCL (Component_Associations (E1),
9035 Component_Associations (E2));
9038 if Nkind (Expression (E1)) = N_Qualified_Expression
9040 Nkind (Expression (E2)) = N_Qualified_Expression
9042 return FCE (Expression (E1), Expression (E2));
9044 -- Check that the subtype marks and any constraints
9049 Indic1 : constant Node_Id := Expression (E1);
9050 Indic2 : constant Node_Id := Expression (E2);
9055 if Nkind (Indic1) /= N_Subtype_Indication then
9057 Nkind (Indic2) /= N_Subtype_Indication
9058 and then Entity (Indic1) = Entity (Indic2);
9060 elsif Nkind (Indic2) /= N_Subtype_Indication then
9062 Nkind (Indic1) /= N_Subtype_Indication
9063 and then Entity (Indic1) = Entity (Indic2);
9066 if Entity (Subtype_Mark (Indic1)) /=
9067 Entity (Subtype_Mark (Indic2))
9072 Elt1 := First (Constraints (Constraint (Indic1)));
9073 Elt2 := First (Constraints (Constraint (Indic2)));
9074 while Present (Elt1) and then Present (Elt2) loop
9075 if not FCE (Elt1, Elt2) then
9088 when N_Attribute_Reference =>
9090 Attribute_Name (E1) = Attribute_Name (E2)
9091 and then FCL (Expressions (E1), Expressions (E2));
9095 Entity (E1) = Entity (E2)
9096 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9097 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9099 when N_Membership_Test
9103 FCE (Left_Opnd (E1), Left_Opnd (E2))
9105 FCE (Right_Opnd (E1), Right_Opnd (E2));
9107 when N_Case_Expression =>
9113 if not FCE (Expression (E1), Expression (E2)) then
9117 Alt1 := First (Alternatives (E1));
9118 Alt2 := First (Alternatives (E2));
9120 if Present (Alt1) /= Present (Alt2) then
9122 elsif No (Alt1) then
9126 if not FCE (Expression (Alt1), Expression (Alt2))
9127 or else not FCL (Discrete_Choices (Alt1),
9128 Discrete_Choices (Alt2))
9139 when N_Character_Literal =>
9141 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9143 when N_Component_Association =>
9145 FCL (Choices (E1), Choices (E2))
9147 FCE (Expression (E1), Expression (E2));
9149 when N_Explicit_Dereference =>
9151 FCE (Prefix (E1), Prefix (E2));
9153 when N_Extension_Aggregate =>
9155 FCL (Expressions (E1), Expressions (E2))
9156 and then Null_Record_Present (E1) =
9157 Null_Record_Present (E2)
9158 and then FCL (Component_Associations (E1),
9159 Component_Associations (E2));
9161 when N_Function_Call =>
9163 FCE (Name (E1), Name (E2))
9165 FCL (Parameter_Associations (E1),
9166 Parameter_Associations (E2));
9168 when N_If_Expression =>
9170 FCL (Expressions (E1), Expressions (E2));
9172 when N_Indexed_Component =>
9174 FCE (Prefix (E1), Prefix (E2))
9176 FCL (Expressions (E1), Expressions (E2));
9178 when N_Integer_Literal =>
9179 return (Intval (E1) = Intval (E2));
9184 when N_Operator_Symbol =>
9186 Chars (E1) = Chars (E2);
9188 when N_Others_Choice =>
9191 when N_Parameter_Association =>
9193 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9194 and then FCE (Explicit_Actual_Parameter (E1),
9195 Explicit_Actual_Parameter (E2));
9197 when N_Qualified_Expression
9199 | N_Unchecked_Type_Conversion
9202 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9204 FCE (Expression (E1), Expression (E2));
9206 when N_Quantified_Expression =>
9207 if not FCE (Condition (E1), Condition (E2)) then
9211 if Present (Loop_Parameter_Specification (E1))
9212 and then Present (Loop_Parameter_Specification (E2))
9215 L1 : constant Node_Id :=
9216 Loop_Parameter_Specification (E1);
9217 L2 : constant Node_Id :=
9218 Loop_Parameter_Specification (E2);
9222 Reverse_Present (L1) = Reverse_Present (L2)
9224 FCE (Defining_Identifier (L1),
9225 Defining_Identifier (L2))
9227 FCE (Discrete_Subtype_Definition (L1),
9228 Discrete_Subtype_Definition (L2));
9231 elsif Present (Iterator_Specification (E1))
9232 and then Present (Iterator_Specification (E2))
9235 I1 : constant Node_Id := Iterator_Specification (E1);
9236 I2 : constant Node_Id := Iterator_Specification (E2);
9240 FCE (Defining_Identifier (I1),
9241 Defining_Identifier (I2))
9243 Of_Present (I1) = Of_Present (I2)
9245 Reverse_Present (I1) = Reverse_Present (I2)
9246 and then FCE (Name (I1), Name (I2))
9247 and then FCE (Subtype_Indication (I1),
9248 Subtype_Indication (I2));
9251 -- The quantified expressions used different specifications to
9252 -- walk their respective ranges.
9260 FCE (Low_Bound (E1), Low_Bound (E2))
9262 FCE (High_Bound (E1), High_Bound (E2));
9264 when N_Real_Literal =>
9265 return (Realval (E1) = Realval (E2));
9267 when N_Selected_Component =>
9269 FCE (Prefix (E1), Prefix (E2))
9271 FCE (Selector_Name (E1), Selector_Name (E2));
9275 FCE (Prefix (E1), Prefix (E2))
9277 FCE (Discrete_Range (E1), Discrete_Range (E2));
9279 when N_String_Literal =>
9281 S1 : constant String_Id := Strval (E1);
9282 S2 : constant String_Id := Strval (E2);
9283 L1 : constant Nat := String_Length (S1);
9284 L2 : constant Nat := String_Length (S2);
9291 for J in 1 .. L1 loop
9292 if Get_String_Char (S1, J) /=
9293 Get_String_Char (S2, J)
9305 Entity (E1) = Entity (E2)
9307 FCE (Right_Opnd (E1), Right_Opnd (E2));
9309 -- All other node types cannot appear in this context. Strictly
9310 -- we should raise a fatal internal error. Instead we just ignore
9311 -- the nodes. This means that if anyone makes a mistake in the
9312 -- expander and mucks an expression tree irretrievably, the result
9313 -- will be a failure to detect a (probably very obscure) case
9314 -- of non-conformance, which is better than bombing on some
9315 -- case where two expressions do in fact conform.
9321 end Fully_Conformant_Expressions;
9323 ----------------------------------------
9324 -- Fully_Conformant_Discrete_Subtypes --
9325 ----------------------------------------
9327 function Fully_Conformant_Discrete_Subtypes
9328 (Given_S1 : Node_Id;
9329 Given_S2 : Node_Id) return Boolean
9331 S1 : constant Node_Id := Original_Node (Given_S1);
9332 S2 : constant Node_Id := Original_Node (Given_S2);
9334 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9335 -- Special-case for a bound given by a discriminant, which in the body
9336 -- is replaced with the discriminal of the enclosing type.
9338 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9339 -- Check both bounds
9341 -----------------------
9342 -- Conforming_Bounds --
9343 -----------------------
9345 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9347 if Is_Entity_Name (B1)
9348 and then Is_Entity_Name (B2)
9349 and then Ekind (Entity (B1)) = E_Discriminant
9351 return Chars (B1) = Chars (B2);
9354 return Fully_Conformant_Expressions (B1, B2);
9356 end Conforming_Bounds;
9358 -----------------------
9359 -- Conforming_Ranges --
9360 -----------------------
9362 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9365 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9367 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9368 end Conforming_Ranges;
9370 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9373 if Nkind (S1) /= Nkind (S2) then
9376 elsif Is_Entity_Name (S1) then
9377 return Entity (S1) = Entity (S2);
9379 elsif Nkind (S1) = N_Range then
9380 return Conforming_Ranges (S1, S2);
9382 elsif Nkind (S1) = N_Subtype_Indication then
9384 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9387 (Range_Expression (Constraint (S1)),
9388 Range_Expression (Constraint (S2)));
9392 end Fully_Conformant_Discrete_Subtypes;
9394 --------------------
9395 -- Install_Entity --
9396 --------------------
9398 procedure Install_Entity (E : Entity_Id) is
9399 Prev : constant Entity_Id := Current_Entity (E);
9401 Set_Is_Immediately_Visible (E);
9402 Set_Current_Entity (E);
9403 Set_Homonym (E, Prev);
9406 ---------------------
9407 -- Install_Formals --
9408 ---------------------
9410 procedure Install_Formals (Id : Entity_Id) is
9413 F := First_Formal (Id);
9414 while Present (F) loop
9418 end Install_Formals;
9420 -----------------------------
9421 -- Is_Interface_Conformant --
9422 -----------------------------
9424 function Is_Interface_Conformant
9425 (Tagged_Type : Entity_Id;
9426 Iface_Prim : Entity_Id;
9427 Prim : Entity_Id) return Boolean
9429 -- The operation may in fact be an inherited (implicit) operation
9430 -- rather than the original interface primitive, so retrieve the
9431 -- ultimate ancestor.
9433 Iface : constant Entity_Id :=
9434 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9435 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9437 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9438 -- Return the controlling formal of Prim
9440 ------------------------
9441 -- Controlling_Formal --
9442 ------------------------
9444 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9448 E := First_Entity (Prim);
9449 while Present (E) loop
9450 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9458 end Controlling_Formal;
9462 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9463 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9465 -- Start of processing for Is_Interface_Conformant
9468 pragma Assert (Is_Subprogram (Iface_Prim)
9469 and then Is_Subprogram (Prim)
9470 and then Is_Dispatching_Operation (Iface_Prim)
9471 and then Is_Dispatching_Operation (Prim));
9473 pragma Assert (Is_Interface (Iface)
9474 or else (Present (Alias (Iface_Prim))
9477 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9479 if Prim = Iface_Prim
9480 or else not Is_Subprogram (Prim)
9481 or else Ekind (Prim) /= Ekind (Iface_Prim)
9482 or else not Is_Dispatching_Operation (Prim)
9483 or else Scope (Prim) /= Scope (Tagged_Type)
9485 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9486 or else not Primitive_Names_Match (Iface_Prim, Prim)
9490 -- The mode of the controlling formals must match
9492 elsif Present (Iface_Ctrl_F)
9493 and then Present (Prim_Ctrl_F)
9494 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9498 -- Case of a procedure, or a function whose result type matches the
9499 -- result type of the interface primitive, or a function that has no
9500 -- controlling result (I or access I).
9502 elsif Ekind (Iface_Prim) = E_Procedure
9503 or else Etype (Prim) = Etype (Iface_Prim)
9504 or else not Has_Controlling_Result (Prim)
9506 return Type_Conformant
9507 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9509 -- Case of a function returning an interface, or an access to one. Check
9510 -- that the return types correspond.
9512 elsif Implements_Interface (Typ, Iface) then
9513 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9515 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9520 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9521 Skip_Controlling_Formals => True);
9527 end Is_Interface_Conformant;
9529 ---------------------------------
9530 -- Is_Non_Overriding_Operation --
9531 ---------------------------------
9533 function Is_Non_Overriding_Operation
9534 (Prev_E : Entity_Id;
9535 New_E : Entity_Id) return Boolean
9539 G_Typ : Entity_Id := Empty;
9541 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9542 -- If F_Type is a derived type associated with a generic actual subtype,
9543 -- then return its Generic_Parent_Type attribute, else return Empty.
9545 function Types_Correspond
9546 (P_Type : Entity_Id;
9547 N_Type : Entity_Id) return Boolean;
9548 -- Returns true if and only if the types (or designated types in the
9549 -- case of anonymous access types) are the same or N_Type is derived
9550 -- directly or indirectly from P_Type.
9552 -----------------------------
9553 -- Get_Generic_Parent_Type --
9554 -----------------------------
9556 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9562 if Is_Derived_Type (F_Typ)
9563 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9565 -- The tree must be traversed to determine the parent subtype in
9566 -- the generic unit, which unfortunately isn't always available
9567 -- via semantic attributes. ??? (Note: The use of Original_Node
9568 -- is needed for cases where a full derived type has been
9571 -- If the parent type is a scalar type, the derivation creates
9572 -- an anonymous base type for it, and the source type is its
9575 if Is_Scalar_Type (F_Typ)
9576 and then not Comes_From_Source (F_Typ)
9580 (Original_Node (Parent (First_Subtype (F_Typ))));
9582 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9584 if Nkind (Defn) = N_Derived_Type_Definition then
9585 Indic := Subtype_Indication (Defn);
9587 if Nkind (Indic) = N_Subtype_Indication then
9588 G_Typ := Entity (Subtype_Mark (Indic));
9590 G_Typ := Entity (Indic);
9593 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9594 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9596 return Generic_Parent_Type (Parent (G_Typ));
9602 end Get_Generic_Parent_Type;
9604 ----------------------
9605 -- Types_Correspond --
9606 ----------------------
9608 function Types_Correspond
9609 (P_Type : Entity_Id;
9610 N_Type : Entity_Id) return Boolean
9612 Prev_Type : Entity_Id := Base_Type (P_Type);
9613 New_Type : Entity_Id := Base_Type (N_Type);
9616 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9617 Prev_Type := Designated_Type (Prev_Type);
9620 if Ekind (New_Type) = E_Anonymous_Access_Type then
9621 New_Type := Designated_Type (New_Type);
9624 if Prev_Type = New_Type then
9627 elsif not Is_Class_Wide_Type (New_Type) then
9628 while Etype (New_Type) /= New_Type loop
9629 New_Type := Etype (New_Type);
9631 if New_Type = Prev_Type then
9637 end Types_Correspond;
9639 -- Start of processing for Is_Non_Overriding_Operation
9642 -- In the case where both operations are implicit derived subprograms
9643 -- then neither overrides the other. This can only occur in certain
9644 -- obscure cases (e.g., derivation from homographs created in a generic
9647 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9650 elsif Ekind (Current_Scope) = E_Package
9651 and then Is_Generic_Instance (Current_Scope)
9652 and then In_Private_Part (Current_Scope)
9653 and then Comes_From_Source (New_E)
9655 -- We examine the formals and result type of the inherited operation,
9656 -- to determine whether their type is derived from (the instance of)
9657 -- a generic type. The first such formal or result type is the one
9660 Formal := First_Formal (Prev_E);
9662 while Present (Formal) loop
9663 F_Typ := Base_Type (Etype (Formal));
9665 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9666 F_Typ := Designated_Type (F_Typ);
9669 G_Typ := Get_Generic_Parent_Type (F_Typ);
9670 exit when Present (G_Typ);
9672 Next_Formal (Formal);
9675 -- If the function dispatches on result check the result type
9677 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9678 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9685 -- If the generic type is a private type, then the original operation
9686 -- was not overriding in the generic, because there was no primitive
9687 -- operation to override.
9689 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9690 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9691 N_Formal_Private_Type_Definition
9695 -- The generic parent type is the ancestor of a formal derived
9696 -- type declaration. We need to check whether it has a primitive
9697 -- operation that should be overridden by New_E in the generic.
9701 P_Formal : Entity_Id;
9702 N_Formal : Entity_Id;
9706 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9709 while Present (Prim_Elt) loop
9710 P_Prim := Node (Prim_Elt);
9712 if Chars (P_Prim) = Chars (New_E)
9713 and then Ekind (P_Prim) = Ekind (New_E)
9715 P_Formal := First_Formal (P_Prim);
9716 N_Formal := First_Formal (New_E);
9717 while Present (P_Formal) and then Present (N_Formal) loop
9718 P_Typ := Etype (P_Formal);
9719 N_Typ := Etype (N_Formal);
9721 if not Types_Correspond (P_Typ, N_Typ) then
9725 Next_Entity (P_Formal);
9726 Next_Entity (N_Formal);
9729 -- Found a matching primitive operation belonging to the
9730 -- formal ancestor type, so the new subprogram is
9734 and then No (N_Formal)
9735 and then (Ekind (New_E) /= E_Function
9738 (Etype (P_Prim), Etype (New_E)))
9744 Next_Elmt (Prim_Elt);
9747 -- If no match found, then the new subprogram does not override
9748 -- in the generic (nor in the instance).
9750 -- If the type in question is not abstract, and the subprogram
9751 -- is, this will be an error if the new operation is in the
9752 -- private part of the instance. Emit a warning now, which will
9753 -- make the subsequent error message easier to understand.
9755 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9756 and then Is_Abstract_Subprogram (Prev_E)
9757 and then In_Private_Part (Current_Scope)
9759 Error_Msg_Node_2 := F_Typ;
9761 ("private operation& in generic unit does not override "
9762 & "any primitive operation of& (RM 12.3 (18))??",
9772 end Is_Non_Overriding_Operation;
9774 -------------------------------------
9775 -- List_Inherited_Pre_Post_Aspects --
9776 -------------------------------------
9778 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9780 if Opt.List_Inherited_Aspects
9781 and then Is_Subprogram_Or_Generic_Subprogram (E)
9784 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9789 for Index in Subps'Range loop
9790 Items := Contract (Subps (Index));
9792 if Present (Items) then
9793 Prag := Pre_Post_Conditions (Items);
9794 while Present (Prag) loop
9795 Error_Msg_Sloc := Sloc (Prag);
9797 if Class_Present (Prag)
9798 and then not Split_PPC (Prag)
9800 if Pragma_Name (Prag) = Name_Precondition then
9802 ("info: & inherits `Pre''Class` aspect from "
9806 ("info: & inherits `Post''Class` aspect from "
9811 Prag := Next_Pragma (Prag);
9817 end List_Inherited_Pre_Post_Aspects;
9819 ------------------------------
9820 -- Make_Inequality_Operator --
9821 ------------------------------
9823 -- S is the defining identifier of an equality operator. We build a
9824 -- subprogram declaration with the right signature. This operation is
9825 -- intrinsic, because it is always expanded as the negation of the
9826 -- call to the equality function.
9828 procedure Make_Inequality_Operator (S : Entity_Id) is
9829 Loc : constant Source_Ptr := Sloc (S);
9832 Op_Name : Entity_Id;
9834 FF : constant Entity_Id := First_Formal (S);
9835 NF : constant Entity_Id := Next_Formal (FF);
9838 -- Check that equality was properly defined, ignore call if not
9845 A : constant Entity_Id :=
9846 Make_Defining_Identifier (Sloc (FF),
9847 Chars => Chars (FF));
9849 B : constant Entity_Id :=
9850 Make_Defining_Identifier (Sloc (NF),
9851 Chars => Chars (NF));
9854 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9856 Formals := New_List (
9857 Make_Parameter_Specification (Loc,
9858 Defining_Identifier => A,
9860 New_Occurrence_Of (Etype (First_Formal (S)),
9861 Sloc (Etype (First_Formal (S))))),
9863 Make_Parameter_Specification (Loc,
9864 Defining_Identifier => B,
9866 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9867 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9870 Make_Subprogram_Declaration (Loc,
9872 Make_Function_Specification (Loc,
9873 Defining_Unit_Name => Op_Name,
9874 Parameter_Specifications => Formals,
9875 Result_Definition =>
9876 New_Occurrence_Of (Standard_Boolean, Loc)));
9878 -- Insert inequality right after equality if it is explicit or after
9879 -- the derived type when implicit. These entities are created only
9880 -- for visibility purposes, and eventually replaced in the course
9881 -- of expansion, so they do not need to be attached to the tree and
9882 -- seen by the back-end. Keeping them internal also avoids spurious
9883 -- freezing problems. The declaration is inserted in the tree for
9884 -- analysis, and removed afterwards. If the equality operator comes
9885 -- from an explicit declaration, attach the inequality immediately
9886 -- after. Else the equality is inherited from a derived type
9887 -- declaration, so insert inequality after that declaration.
9889 if No (Alias (S)) then
9890 Insert_After (Unit_Declaration_Node (S), Decl);
9891 elsif Is_List_Member (Parent (S)) then
9892 Insert_After (Parent (S), Decl);
9894 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9897 Mark_Rewrite_Insertion (Decl);
9898 Set_Is_Intrinsic_Subprogram (Op_Name);
9901 Set_Has_Completion (Op_Name);
9902 Set_Corresponding_Equality (Op_Name, S);
9903 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9905 end Make_Inequality_Operator;
9907 ----------------------
9908 -- May_Need_Actuals --
9909 ----------------------
9911 procedure May_Need_Actuals (Fun : Entity_Id) is
9916 F := First_Formal (Fun);
9918 while Present (F) loop
9919 if No (Default_Value (F)) then
9927 Set_Needs_No_Actuals (Fun, B);
9928 end May_Need_Actuals;
9930 ---------------------
9931 -- Mode_Conformant --
9932 ---------------------
9934 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9937 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9939 end Mode_Conformant;
9941 ---------------------------
9942 -- New_Overloaded_Entity --
9943 ---------------------------
9945 procedure New_Overloaded_Entity
9947 Derived_Type : Entity_Id := Empty)
9949 Overridden_Subp : Entity_Id := Empty;
9950 -- Set if the current scope has an operation that is type-conformant
9951 -- with S, and becomes hidden by S.
9953 Is_Primitive_Subp : Boolean;
9954 -- Set to True if the new subprogram is primitive
9957 -- Entity that S overrides
9959 Prev_Vis : Entity_Id := Empty;
9960 -- Predecessor of E in Homonym chain
9962 procedure Check_For_Primitive_Subprogram
9963 (Is_Primitive : out Boolean;
9964 Is_Overriding : Boolean := False);
9965 -- If the subprogram being analyzed is a primitive operation of the type
9966 -- of a formal or result, set the Has_Primitive_Operations flag on the
9967 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9968 -- corresponding flag on the entity itself for later use.
9970 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
9971 -- True if a) E is a subprogram whose first formal is a concurrent type
9972 -- defined in the scope of E that has some entry or subprogram whose
9973 -- profile matches E, or b) E is an internally built dispatching
9974 -- subprogram of a protected type and there is a matching subprogram
9975 -- defined in the enclosing scope of the protected type, or c) E is
9976 -- an entry of a synchronized type and a matching procedure has been
9977 -- previously defined in the enclosing scope of the synchronized type.
9979 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9980 -- Check that E is declared in the private part of the current package,
9981 -- or in the package body, where it may hide a previous declaration.
9982 -- We can't use In_Private_Part by itself because this flag is also
9983 -- set when freezing entities, so we must examine the place of the
9984 -- declaration in the tree, and recognize wrapper packages as well.
9986 function Is_Overriding_Alias
9988 New_E : Entity_Id) return Boolean;
9989 -- Check whether new subprogram and old subprogram are both inherited
9990 -- from subprograms that have distinct dispatch table entries. This can
9991 -- occur with derivations from instances with accidental homonyms. The
9992 -- function is conservative given that the converse is only true within
9993 -- instances that contain accidental overloadings.
9995 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
9996 -- Report conflict between entities S and E
9998 ------------------------------------
9999 -- Check_For_Primitive_Subprogram --
10000 ------------------------------------
10002 procedure Check_For_Primitive_Subprogram
10003 (Is_Primitive : out Boolean;
10004 Is_Overriding : Boolean := False)
10006 Formal : Entity_Id;
10010 function Visible_Part_Type (T : Entity_Id) return Boolean;
10011 -- Returns true if T is declared in the visible part of the current
10012 -- package scope; otherwise returns false. Assumes that T is declared
10015 procedure Check_Private_Overriding (T : Entity_Id);
10016 -- Checks that if a primitive abstract subprogram of a visible
10017 -- abstract type is declared in a private part, then it must override
10018 -- an abstract subprogram declared in the visible part. Also checks
10019 -- that if a primitive function with a controlling result is declared
10020 -- in a private part, then it must override a function declared in
10021 -- the visible part.
10023 ------------------------------
10024 -- Check_Private_Overriding --
10025 ------------------------------
10027 procedure Check_Private_Overriding (T : Entity_Id) is
10028 function Overrides_Private_Part_Op return Boolean;
10029 -- This detects the special case where the overriding subprogram
10030 -- is overriding a subprogram that was declared in the same
10031 -- private part. That case is illegal by 3.9.3(10).
10033 function Overrides_Visible_Function
10034 (Partial_View : Entity_Id) return Boolean;
10035 -- True if S overrides a function in the visible part. The
10036 -- overridden function could be explicitly or implicitly declared.
10038 -------------------------------
10039 -- Overrides_Private_Part_Op --
10040 -------------------------------
10042 function Overrides_Private_Part_Op return Boolean is
10043 Over_Decl : constant Node_Id :=
10044 Unit_Declaration_Node (Overridden_Operation (S));
10045 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10048 pragma Assert (Is_Overriding);
10050 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10052 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10054 return In_Same_List (Over_Decl, Subp_Decl);
10055 end Overrides_Private_Part_Op;
10057 --------------------------------
10058 -- Overrides_Visible_Function --
10059 --------------------------------
10061 function Overrides_Visible_Function
10062 (Partial_View : Entity_Id) return Boolean
10065 if not Is_Overriding or else not Has_Homonym (S) then
10069 if not Present (Partial_View) then
10073 -- Search through all the homonyms H of S in the current
10074 -- package spec, and return True if we find one that matches.
10075 -- Note that Parent (H) will be the declaration of the
10076 -- partial view of T for a match.
10079 H : Entity_Id := S;
10083 exit when not Present (H) or else Scope (H) /= Scope (S);
10087 N_Private_Extension_Declaration,
10088 N_Private_Type_Declaration)
10089 and then Defining_Identifier (Parent (H)) = Partial_View
10097 end Overrides_Visible_Function;
10099 -- Start of processing for Check_Private_Overriding
10102 if Is_Package_Or_Generic_Package (Current_Scope)
10103 and then In_Private_Part (Current_Scope)
10104 and then Visible_Part_Type (T)
10105 and then not In_Instance
10107 if Is_Abstract_Type (T)
10108 and then Is_Abstract_Subprogram (S)
10109 and then (not Is_Overriding
10110 or else not Is_Abstract_Subprogram (E)
10111 or else Overrides_Private_Part_Op)
10114 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10117 elsif Ekind (S) = E_Function then
10119 Partial_View : constant Entity_Id :=
10120 Incomplete_Or_Partial_View (T);
10123 if not Overrides_Visible_Function (Partial_View) then
10125 -- Here, S is "function ... return T;" declared in
10126 -- the private part, not overriding some visible
10127 -- operation. That's illegal in the tagged case
10128 -- (but not if the private type is untagged).
10130 if ((Present (Partial_View)
10131 and then Is_Tagged_Type (Partial_View))
10132 or else (not Present (Partial_View)
10133 and then Is_Tagged_Type (T)))
10134 and then T = Base_Type (Etype (S))
10137 ("private function with tagged result must"
10138 & " override visible-part function", S);
10140 ("\move subprogram to the visible part"
10141 & " (RM 3.9.3(10))", S);
10143 -- AI05-0073: extend this test to the case of a
10144 -- function with a controlling access result.
10146 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10147 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10149 not Is_Class_Wide_Type
10150 (Designated_Type (Etype (S)))
10151 and then Ada_Version >= Ada_2012
10154 ("private function with controlling access "
10155 & "result must override visible-part function",
10158 ("\move subprogram to the visible part"
10159 & " (RM 3.9.3(10))", S);
10165 end Check_Private_Overriding;
10167 -----------------------
10168 -- Visible_Part_Type --
10169 -----------------------
10171 function Visible_Part_Type (T : Entity_Id) return Boolean is
10172 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10175 -- If the entity is a private type, then it must be declared in a
10178 if Ekind (T) in Private_Kind then
10181 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10184 elsif Is_List_Member (Declaration_Node (T))
10185 and then List_Containing (Declaration_Node (T)) =
10186 Visible_Declarations (Specification (P))
10193 end Visible_Part_Type;
10195 -- Start of processing for Check_For_Primitive_Subprogram
10198 Is_Primitive := False;
10200 if not Comes_From_Source (S) then
10203 -- If subprogram is at library level, it is not primitive operation
10205 elsif Current_Scope = Standard_Standard then
10208 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10209 and then not In_Package_Body (Current_Scope))
10210 or else Is_Overriding
10212 -- For function, check return type
10214 if Ekind (S) = E_Function then
10215 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10216 F_Typ := Designated_Type (Etype (S));
10218 F_Typ := Etype (S);
10221 B_Typ := Base_Type (F_Typ);
10223 if Scope (B_Typ) = Current_Scope
10224 and then not Is_Class_Wide_Type (B_Typ)
10225 and then not Is_Generic_Type (B_Typ)
10227 Is_Primitive := True;
10228 Set_Has_Primitive_Operations (B_Typ);
10229 Set_Is_Primitive (S);
10230 Check_Private_Overriding (B_Typ);
10232 -- The Ghost policy in effect at the point of declaration
10233 -- or a tagged type and a primitive operation must match
10234 -- (SPARK RM 6.9(16)).
10236 Check_Ghost_Primitive (S, B_Typ);
10240 -- For all subprograms, check formals
10242 Formal := First_Formal (S);
10243 while Present (Formal) loop
10244 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10245 F_Typ := Designated_Type (Etype (Formal));
10247 F_Typ := Etype (Formal);
10250 B_Typ := Base_Type (F_Typ);
10252 if Ekind (B_Typ) = E_Access_Subtype then
10253 B_Typ := Base_Type (B_Typ);
10256 if Scope (B_Typ) = Current_Scope
10257 and then not Is_Class_Wide_Type (B_Typ)
10258 and then not Is_Generic_Type (B_Typ)
10260 Is_Primitive := True;
10261 Set_Is_Primitive (S);
10262 Set_Has_Primitive_Operations (B_Typ);
10263 Check_Private_Overriding (B_Typ);
10265 -- The Ghost policy in effect at the point of declaration
10266 -- of a tagged type and a primitive operation must match
10267 -- (SPARK RM 6.9(16)).
10269 Check_Ghost_Primitive (S, B_Typ);
10272 Next_Formal (Formal);
10275 -- Special case: An equality function can be redefined for a type
10276 -- occurring in a declarative part, and won't otherwise be treated as
10277 -- a primitive because it doesn't occur in a package spec and doesn't
10278 -- override an inherited subprogram. It's important that we mark it
10279 -- primitive so it can be returned by Collect_Primitive_Operations
10280 -- and be used in composing the equality operation of later types
10281 -- that have a component of the type.
10283 elsif Chars (S) = Name_Op_Eq
10284 and then Etype (S) = Standard_Boolean
10286 B_Typ := Base_Type (Etype (First_Formal (S)));
10288 if Scope (B_Typ) = Current_Scope
10290 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10291 and then not Is_Limited_Type (B_Typ)
10293 Is_Primitive := True;
10294 Set_Is_Primitive (S);
10295 Set_Has_Primitive_Operations (B_Typ);
10296 Check_Private_Overriding (B_Typ);
10298 -- The Ghost policy in effect at the point of declaration of a
10299 -- tagged type and a primitive operation must match
10300 -- (SPARK RM 6.9(16)).
10302 Check_Ghost_Primitive (S, B_Typ);
10305 end Check_For_Primitive_Subprogram;
10307 --------------------------------------
10308 -- Has_Matching_Entry_Or_Subprogram --
10309 --------------------------------------
10311 function Has_Matching_Entry_Or_Subprogram
10312 (E : Entity_Id) return Boolean
10314 function Check_Conforming_Parameters
10315 (E1_Param : Node_Id;
10316 E2_Param : Node_Id) return Boolean;
10317 -- Starting from the given parameters, check that all the parameters
10318 -- of two entries or subprograms are subtype conformant. Used to skip
10319 -- the check on the controlling argument.
10321 function Matching_Entry_Or_Subprogram
10322 (Conc_Typ : Entity_Id;
10323 Subp : Entity_Id) return Entity_Id;
10324 -- Return the first entry or subprogram of the given concurrent type
10325 -- whose name matches the name of Subp and has a profile conformant
10326 -- with Subp; return Empty if not found.
10328 function Matching_Dispatching_Subprogram
10329 (Conc_Typ : Entity_Id;
10330 Ent : Entity_Id) return Entity_Id;
10331 -- Return the first dispatching primitive of Conc_Type defined in the
10332 -- enclosing scope of Conc_Type (i.e. before the full definition of
10333 -- this concurrent type) whose name matches the entry Ent and has a
10334 -- profile conformant with the profile of the corresponding (not yet
10335 -- built) dispatching primitive of Ent; return Empty if not found.
10337 function Matching_Original_Protected_Subprogram
10338 (Prot_Typ : Entity_Id;
10339 Subp : Entity_Id) return Entity_Id;
10340 -- Return the first subprogram defined in the enclosing scope of
10341 -- Prot_Typ (before the full definition of this protected type)
10342 -- whose name matches the original name of Subp and has a profile
10343 -- conformant with the profile of Subp; return Empty if not found.
10345 ---------------------------------
10346 -- Check_Confirming_Parameters --
10347 ---------------------------------
10349 function Check_Conforming_Parameters
10350 (E1_Param : Node_Id;
10351 E2_Param : Node_Id) return Boolean
10353 Param_E1 : Node_Id := E1_Param;
10354 Param_E2 : Node_Id := E2_Param;
10357 while Present (Param_E1) and then Present (Param_E2) loop
10358 if Ekind (Defining_Identifier (Param_E1)) /=
10359 Ekind (Defining_Identifier (Param_E2))
10362 (Find_Parameter_Type (Param_E1),
10363 Find_Parameter_Type (Param_E2),
10364 Subtype_Conformant)
10373 -- The candidate is not valid if one of the two lists contains
10374 -- more parameters than the other
10376 return No (Param_E1) and then No (Param_E2);
10377 end Check_Conforming_Parameters;
10379 ----------------------------------
10380 -- Matching_Entry_Or_Subprogram --
10381 ----------------------------------
10383 function Matching_Entry_Or_Subprogram
10384 (Conc_Typ : Entity_Id;
10385 Subp : Entity_Id) return Entity_Id
10390 E := First_Entity (Conc_Typ);
10391 while Present (E) loop
10392 if Chars (Subp) = Chars (E)
10393 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10395 Check_Conforming_Parameters
10396 (First (Parameter_Specifications (Parent (E))),
10397 Next (First (Parameter_Specifications (Parent (Subp)))))
10406 end Matching_Entry_Or_Subprogram;
10408 -------------------------------------
10409 -- Matching_Dispatching_Subprogram --
10410 -------------------------------------
10412 function Matching_Dispatching_Subprogram
10413 (Conc_Typ : Entity_Id;
10414 Ent : Entity_Id) return Entity_Id
10419 -- Search for entities in the enclosing scope of this synchonized
10422 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10423 Push_Scope (Scope (Conc_Typ));
10424 E := Current_Entity_In_Scope (Ent);
10427 while Present (E) loop
10428 if Scope (E) = Scope (Conc_Typ)
10429 and then Comes_From_Source (E)
10430 and then Ekind (E) = E_Procedure
10431 and then Present (First_Entity (E))
10432 and then Is_Controlling_Formal (First_Entity (E))
10433 and then Etype (First_Entity (E)) = Conc_Typ
10435 Check_Conforming_Parameters
10436 (First (Parameter_Specifications (Parent (Ent))),
10437 Next (First (Parameter_Specifications (Parent (E)))))
10446 end Matching_Dispatching_Subprogram;
10448 --------------------------------------------
10449 -- Matching_Original_Protected_Subprogram --
10450 --------------------------------------------
10452 function Matching_Original_Protected_Subprogram
10453 (Prot_Typ : Entity_Id;
10454 Subp : Entity_Id) return Entity_Id
10456 ICF : constant Boolean :=
10457 Is_Controlling_Formal (First_Entity (Subp));
10461 -- Temporarily decorate the first parameter of Subp as controlling
10462 -- formal, required to invoke Subtype_Conformant.
10464 Set_Is_Controlling_Formal (First_Entity (Subp));
10467 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10469 while Present (E) loop
10470 if Scope (E) = Scope (Prot_Typ)
10471 and then Comes_From_Source (E)
10472 and then Ekind (Subp) = Ekind (E)
10473 and then Present (First_Entity (E))
10474 and then Is_Controlling_Formal (First_Entity (E))
10475 and then Etype (First_Entity (E)) = Prot_Typ
10476 and then Subtype_Conformant (Subp, E,
10477 Skip_Controlling_Formals => True)
10479 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10486 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10489 end Matching_Original_Protected_Subprogram;
10491 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10494 -- Case 1: E is a subprogram whose first formal is a concurrent type
10495 -- defined in the scope of E that has an entry or subprogram whose
10496 -- profile matches E.
10498 if Comes_From_Source (E)
10499 and then Is_Subprogram (E)
10500 and then Present (First_Entity (E))
10501 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10504 Scope (Corresponding_Concurrent_Type
10505 (Etype (First_Entity (E))))
10508 (Matching_Entry_Or_Subprogram
10509 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10512 Report_Conflict (E,
10513 Matching_Entry_Or_Subprogram
10514 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10519 -- Case 2: E is an internally built dispatching subprogram of a
10520 -- protected type and there is a subprogram defined in the enclosing
10521 -- scope of the protected type that has the original name of E and
10522 -- its profile is conformant with the profile of E. We check the
10523 -- name of the original protected subprogram associated with E since
10524 -- the expander builds dispatching primitives of protected functions
10525 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10527 elsif not Comes_From_Source (E)
10528 and then Is_Subprogram (E)
10529 and then Present (First_Entity (E))
10530 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10531 and then Present (Original_Protected_Subprogram (E))
10534 (Matching_Original_Protected_Subprogram
10535 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10538 Report_Conflict (E,
10539 Matching_Original_Protected_Subprogram
10540 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10544 -- Case 3: E is an entry of a synchronized type and a matching
10545 -- procedure has been previously defined in the enclosing scope
10546 -- of the synchronized type.
10548 elsif Comes_From_Source (E)
10549 and then Ekind (E) = E_Entry
10551 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10553 Report_Conflict (E,
10554 Matching_Dispatching_Subprogram (Current_Scope, E));
10559 end Has_Matching_Entry_Or_Subprogram;
10561 ----------------------------
10562 -- Is_Private_Declaration --
10563 ----------------------------
10565 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10566 Decl : constant Node_Id := Unit_Declaration_Node (E);
10567 Priv_Decls : List_Id;
10570 if Is_Package_Or_Generic_Package (Current_Scope)
10571 and then In_Private_Part (Current_Scope)
10574 Private_Declarations (Package_Specification (Current_Scope));
10576 return In_Package_Body (Current_Scope)
10578 (Is_List_Member (Decl)
10579 and then List_Containing (Decl) = Priv_Decls)
10580 or else (Nkind (Parent (Decl)) = N_Package_Specification
10582 Is_Compilation_Unit
10583 (Defining_Entity (Parent (Decl)))
10584 and then List_Containing (Parent (Parent (Decl))) =
10589 end Is_Private_Declaration;
10591 --------------------------
10592 -- Is_Overriding_Alias --
10593 --------------------------
10595 function Is_Overriding_Alias
10596 (Old_E : Entity_Id;
10597 New_E : Entity_Id) return Boolean
10599 AO : constant Entity_Id := Alias (Old_E);
10600 AN : constant Entity_Id := Alias (New_E);
10603 return Scope (AO) /= Scope (AN)
10604 or else No (DTC_Entity (AO))
10605 or else No (DTC_Entity (AN))
10606 or else DT_Position (AO) = DT_Position (AN);
10607 end Is_Overriding_Alias;
10609 ---------------------
10610 -- Report_Conflict --
10611 ---------------------
10613 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10615 Error_Msg_Sloc := Sloc (E);
10617 -- Generate message, with useful additional warning if in generic
10619 if Is_Generic_Unit (E) then
10620 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10621 Error_Msg_N ("\& conflicts with declaration#", S);
10623 Error_Msg_N ("& conflicts with declaration#", S);
10625 end Report_Conflict;
10627 -- Start of processing for New_Overloaded_Entity
10630 -- We need to look for an entity that S may override. This must be a
10631 -- homonym in the current scope, so we look for the first homonym of
10632 -- S in the current scope as the starting point for the search.
10634 E := Current_Entity_In_Scope (S);
10636 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10637 -- They are directly added to the list of primitive operations of
10638 -- Derived_Type, unless this is a rederivation in the private part
10639 -- of an operation that was already derived in the visible part of
10640 -- the current package.
10642 if Ada_Version >= Ada_2005
10643 and then Present (Derived_Type)
10644 and then Present (Alias (S))
10645 and then Is_Dispatching_Operation (Alias (S))
10646 and then Present (Find_Dispatching_Type (Alias (S)))
10647 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10649 -- For private types, when the full-view is processed we propagate to
10650 -- the full view the non-overridden entities whose attribute "alias"
10651 -- references an interface primitive. These entities were added by
10652 -- Derive_Subprograms to ensure that interface primitives are
10655 -- Inside_Freeze_Actions is non zero when S corresponds with an
10656 -- internal entity that links an interface primitive with its
10657 -- covering primitive through attribute Interface_Alias (see
10658 -- Add_Internal_Interface_Entities).
10660 if Inside_Freezing_Actions = 0
10661 and then Is_Package_Or_Generic_Package (Current_Scope)
10662 and then In_Private_Part (Current_Scope)
10663 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10664 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10665 and then Full_View (Defining_Identifier (Parent (E)))
10666 = Defining_Identifier (Parent (S))
10667 and then Alias (E) = Alias (S)
10669 Check_Operation_From_Private_View (S, E);
10670 Set_Is_Dispatching_Operation (S);
10675 Enter_Overloaded_Entity (S);
10676 Check_Dispatching_Operation (S, Empty);
10677 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10683 -- For synchronized types check conflicts of this entity with previously
10684 -- defined entities.
10686 if Ada_Version >= Ada_2005
10687 and then Has_Matching_Entry_Or_Subprogram (S)
10692 -- If there is no homonym then this is definitely not overriding
10695 Enter_Overloaded_Entity (S);
10696 Check_Dispatching_Operation (S, Empty);
10697 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10699 -- If subprogram has an explicit declaration, check whether it has an
10700 -- overriding indicator.
10702 if Comes_From_Source (S) then
10703 Check_Synchronized_Overriding (S, Overridden_Subp);
10705 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10706 -- it may have overridden some hidden inherited primitive. Update
10707 -- Overridden_Subp to avoid spurious errors when checking the
10708 -- overriding indicator.
10710 if Ada_Version >= Ada_2012
10711 and then No (Overridden_Subp)
10712 and then Is_Dispatching_Operation (S)
10713 and then Present (Overridden_Operation (S))
10715 Overridden_Subp := Overridden_Operation (S);
10718 Check_Overriding_Indicator
10719 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10721 -- The Ghost policy in effect at the point of declaration of a
10722 -- parent subprogram and an overriding subprogram must match
10723 -- (SPARK RM 6.9(17)).
10725 Check_Ghost_Overriding (S, Overridden_Subp);
10728 -- If there is a homonym that is not overloadable, then we have an
10729 -- error, except for the special cases checked explicitly below.
10731 elsif not Is_Overloadable (E) then
10733 -- Check for spurious conflict produced by a subprogram that has the
10734 -- same name as that of the enclosing generic package. The conflict
10735 -- occurs within an instance, between the subprogram and the renaming
10736 -- declaration for the package. After the subprogram, the package
10737 -- renaming declaration becomes hidden.
10739 if Ekind (E) = E_Package
10740 and then Present (Renamed_Object (E))
10741 and then Renamed_Object (E) = Current_Scope
10742 and then Nkind (Parent (Renamed_Object (E))) =
10743 N_Package_Specification
10744 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10747 Set_Is_Immediately_Visible (E, False);
10748 Enter_Overloaded_Entity (S);
10749 Set_Homonym (S, Homonym (E));
10750 Check_Dispatching_Operation (S, Empty);
10751 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10753 -- If the subprogram is implicit it is hidden by the previous
10754 -- declaration. However if it is dispatching, it must appear in the
10755 -- dispatch table anyway, because it can be dispatched to even if it
10756 -- cannot be called directly.
10758 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10759 Set_Scope (S, Current_Scope);
10761 if Is_Dispatching_Operation (Alias (S)) then
10762 Check_Dispatching_Operation (S, Empty);
10768 Report_Conflict (S, E);
10772 -- E exists and is overloadable
10775 Check_Synchronized_Overriding (S, Overridden_Subp);
10777 -- Loop through E and its homonyms to determine if any of them is
10778 -- the candidate for overriding by S.
10780 while Present (E) loop
10782 -- Definitely not interesting if not in the current scope
10784 if Scope (E) /= Current_Scope then
10787 -- A function can overload the name of an abstract state. The
10788 -- state can be viewed as a function with a profile that cannot
10789 -- be matched by anything.
10791 elsif Ekind (S) = E_Function
10792 and then Ekind (E) = E_Abstract_State
10794 Enter_Overloaded_Entity (S);
10797 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10798 -- procedures locate the internally generated spec. We enforce
10799 -- mode conformance since a tagged type may inherit from
10800 -- interfaces several null primitives which differ only in
10801 -- the mode of the formals.
10803 elsif not Comes_From_Source (S)
10804 and then Is_Null_Procedure (S)
10805 and then not Mode_Conformant (E, S)
10809 -- Check if we have type conformance
10811 elsif Type_Conformant (E, S) then
10813 -- If the old and new entities have the same profile and one
10814 -- is not the body of the other, then this is an error, unless
10815 -- one of them is implicitly declared.
10817 -- There are some cases when both can be implicit, for example
10818 -- when both a literal and a function that overrides it are
10819 -- inherited in a derivation, or when an inherited operation
10820 -- of a tagged full type overrides the inherited operation of
10821 -- a private extension. Ada 83 had a special rule for the
10822 -- literal case. In Ada 95, the later implicit operation hides
10823 -- the former, and the literal is always the former. In the
10824 -- odd case where both are derived operations declared at the
10825 -- same point, both operations should be declared, and in that
10826 -- case we bypass the following test and proceed to the next
10827 -- part. This can only occur for certain obscure cases in
10828 -- instances, when an operation on a type derived from a formal
10829 -- private type does not override a homograph inherited from
10830 -- the actual. In subsequent derivations of such a type, the
10831 -- DT positions of these operations remain distinct, if they
10834 if Present (Alias (S))
10835 and then (No (Alias (E))
10836 or else Comes_From_Source (E)
10837 or else Is_Abstract_Subprogram (S)
10839 (Is_Dispatching_Operation (E)
10840 and then Is_Overriding_Alias (E, S)))
10841 and then Ekind (E) /= E_Enumeration_Literal
10843 -- When an derived operation is overloaded it may be due to
10844 -- the fact that the full view of a private extension
10845 -- re-inherits. It has to be dealt with.
10847 if Is_Package_Or_Generic_Package (Current_Scope)
10848 and then In_Private_Part (Current_Scope)
10850 Check_Operation_From_Private_View (S, E);
10853 -- In any case the implicit operation remains hidden by the
10854 -- existing declaration, which is overriding. Indicate that
10855 -- E overrides the operation from which S is inherited.
10857 if Present (Alias (S)) then
10858 Set_Overridden_Operation (E, Alias (S));
10859 Inherit_Subprogram_Contract (E, Alias (S));
10862 Set_Overridden_Operation (E, S);
10863 Inherit_Subprogram_Contract (E, S);
10866 if Comes_From_Source (E) then
10867 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10869 -- The Ghost policy in effect at the point of declaration
10870 -- of a parent subprogram and an overriding subprogram
10871 -- must match (SPARK RM 6.9(17)).
10873 Check_Ghost_Overriding (E, S);
10878 -- Within an instance, the renaming declarations for actual
10879 -- subprograms may become ambiguous, but they do not hide each
10882 elsif Ekind (E) /= E_Entry
10883 and then not Comes_From_Source (E)
10884 and then not Is_Generic_Instance (E)
10885 and then (Present (Alias (E))
10886 or else Is_Intrinsic_Subprogram (E))
10887 and then (not In_Instance
10888 or else No (Parent (E))
10889 or else Nkind (Unit_Declaration_Node (E)) /=
10890 N_Subprogram_Renaming_Declaration)
10892 -- A subprogram child unit is not allowed to override an
10893 -- inherited subprogram (10.1.1(20)).
10895 if Is_Child_Unit (S) then
10897 ("child unit overrides inherited subprogram in parent",
10902 if Is_Non_Overriding_Operation (E, S) then
10903 Enter_Overloaded_Entity (S);
10905 if No (Derived_Type)
10906 or else Is_Tagged_Type (Derived_Type)
10908 Check_Dispatching_Operation (S, Empty);
10914 -- E is a derived operation or an internal operator which
10915 -- is being overridden. Remove E from further visibility.
10916 -- Furthermore, if E is a dispatching operation, it must be
10917 -- replaced in the list of primitive operations of its type
10918 -- (see Override_Dispatching_Operation).
10920 Overridden_Subp := E;
10926 Prev := First_Entity (Current_Scope);
10927 while Present (Prev) and then Next_Entity (Prev) /= E loop
10928 Next_Entity (Prev);
10931 -- It is possible for E to be in the current scope and
10932 -- yet not in the entity chain. This can only occur in a
10933 -- generic context where E is an implicit concatenation
10934 -- in the formal part, because in a generic body the
10935 -- entity chain starts with the formals.
10937 -- In GNATprove mode, a wrapper for an operation with
10938 -- axiomatization may be a homonym of another declaration
10939 -- for an actual subprogram (needs refinement ???).
10943 and then GNATprove_Mode
10945 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10946 N_Subprogram_Renaming_Declaration
10950 pragma Assert (Chars (E) = Name_Op_Concat);
10955 -- E must be removed both from the entity_list of the
10956 -- current scope, and from the visibility chain.
10958 if Debug_Flag_E then
10959 Write_Str ("Override implicit operation ");
10960 Write_Int (Int (E));
10964 -- If E is a predefined concatenation, it stands for four
10965 -- different operations. As a result, a single explicit
10966 -- declaration does not hide it. In a possible ambiguous
10967 -- situation, Disambiguate chooses the user-defined op,
10968 -- so it is correct to retain the previous internal one.
10970 if Chars (E) /= Name_Op_Concat
10971 or else Ekind (E) /= E_Operator
10973 -- For nondispatching derived operations that are
10974 -- overridden by a subprogram declared in the private
10975 -- part of a package, we retain the derived subprogram
10976 -- but mark it as not immediately visible. If the
10977 -- derived operation was declared in the visible part
10978 -- then this ensures that it will still be visible
10979 -- outside the package with the proper signature
10980 -- (calls from outside must also be directed to this
10981 -- version rather than the overriding one, unlike the
10982 -- dispatching case). Calls from inside the package
10983 -- will still resolve to the overriding subprogram
10984 -- since the derived one is marked as not visible
10985 -- within the package.
10987 -- If the private operation is dispatching, we achieve
10988 -- the overriding by keeping the implicit operation
10989 -- but setting its alias to be the overriding one. In
10990 -- this fashion the proper body is executed in all
10991 -- cases, but the original signature is used outside
10994 -- If the overriding is not in the private part, we
10995 -- remove the implicit operation altogether.
10997 if Is_Private_Declaration (S) then
10998 if not Is_Dispatching_Operation (E) then
10999 Set_Is_Immediately_Visible (E, False);
11001 -- Work done in Override_Dispatching_Operation,
11002 -- so nothing else needs to be done here.
11008 -- Find predecessor of E in Homonym chain
11010 if E = Current_Entity (E) then
11013 Prev_Vis := Current_Entity (E);
11014 while Homonym (Prev_Vis) /= E loop
11015 Prev_Vis := Homonym (Prev_Vis);
11019 if Prev_Vis /= Empty then
11021 -- Skip E in the visibility chain
11023 Set_Homonym (Prev_Vis, Homonym (E));
11026 Set_Name_Entity_Id (Chars (E), Homonym (E));
11029 Set_Next_Entity (Prev, Next_Entity (E));
11031 if No (Next_Entity (Prev)) then
11032 Set_Last_Entity (Current_Scope, Prev);
11037 Enter_Overloaded_Entity (S);
11039 -- For entities generated by Derive_Subprograms the
11040 -- overridden operation is the inherited primitive
11041 -- (which is available through the attribute alias).
11043 if not (Comes_From_Source (E))
11044 and then Is_Dispatching_Operation (E)
11045 and then Find_Dispatching_Type (E) =
11046 Find_Dispatching_Type (S)
11047 and then Present (Alias (E))
11048 and then Comes_From_Source (Alias (E))
11050 Set_Overridden_Operation (S, Alias (E));
11051 Inherit_Subprogram_Contract (S, Alias (E));
11053 -- Normal case of setting entity as overridden
11055 -- Note: Static_Initialization and Overridden_Operation
11056 -- attributes use the same field in subprogram entities.
11057 -- Static_Initialization is only defined for internal
11058 -- initialization procedures, where Overridden_Operation
11059 -- is irrelevant. Therefore the setting of this attribute
11060 -- must check whether the target is an init_proc.
11062 elsif not Is_Init_Proc (S) then
11063 Set_Overridden_Operation (S, E);
11064 Inherit_Subprogram_Contract (S, E);
11067 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11069 -- The Ghost policy in effect at the point of declaration
11070 -- of a parent subprogram and an overriding subprogram
11071 -- must match (SPARK RM 6.9(17)).
11073 Check_Ghost_Overriding (S, E);
11075 -- If S is a user-defined subprogram or a null procedure
11076 -- expanded to override an inherited null procedure, or a
11077 -- predefined dispatching primitive then indicate that E
11078 -- overrides the operation from which S is inherited.
11080 if Comes_From_Source (S)
11082 (Present (Parent (S))
11084 Nkind (Parent (S)) = N_Procedure_Specification
11086 Null_Present (Parent (S)))
11088 (Present (Alias (E))
11090 Is_Predefined_Dispatching_Operation (Alias (E)))
11092 if Present (Alias (E)) then
11093 Set_Overridden_Operation (S, Alias (E));
11094 Inherit_Subprogram_Contract (S, Alias (E));
11098 if Is_Dispatching_Operation (E) then
11100 -- An overriding dispatching subprogram inherits the
11101 -- convention of the overridden subprogram (AI-117).
11103 Set_Convention (S, Convention (E));
11104 Check_Dispatching_Operation (S, E);
11107 Check_Dispatching_Operation (S, Empty);
11110 Check_For_Primitive_Subprogram
11111 (Is_Primitive_Subp, Is_Overriding => True);
11112 goto Check_Inequality;
11115 -- Apparent redeclarations in instances can occur when two
11116 -- formal types get the same actual type. The subprograms in
11117 -- in the instance are legal, even if not callable from the
11118 -- outside. Calls from within are disambiguated elsewhere.
11119 -- For dispatching operations in the visible part, the usual
11120 -- rules apply, and operations with the same profile are not
11121 -- legal (B830001).
11123 elsif (In_Instance_Visible_Part
11124 and then not Is_Dispatching_Operation (E))
11125 or else In_Instance_Not_Visible
11129 -- Here we have a real error (identical profile)
11132 Error_Msg_Sloc := Sloc (E);
11134 -- Avoid cascaded errors if the entity appears in
11135 -- subsequent calls.
11137 Set_Scope (S, Current_Scope);
11139 -- Generate error, with extra useful warning for the case
11140 -- of a generic instance with no completion.
11142 if Is_Generic_Instance (S)
11143 and then not Has_Completion (E)
11146 ("instantiation cannot provide body for&", S);
11147 Error_Msg_N ("\& conflicts with declaration#", S);
11149 Error_Msg_N ("& conflicts with declaration#", S);
11156 -- If one subprogram has an access parameter and the other
11157 -- a parameter of an access type, calls to either might be
11158 -- ambiguous. Verify that parameters match except for the
11159 -- access parameter.
11161 if May_Hide_Profile then
11167 F1 := First_Formal (S);
11168 F2 := First_Formal (E);
11169 while Present (F1) and then Present (F2) loop
11170 if Is_Access_Type (Etype (F1)) then
11171 if not Is_Access_Type (Etype (F2))
11172 or else not Conforming_Types
11173 (Designated_Type (Etype (F1)),
11174 Designated_Type (Etype (F2)),
11177 May_Hide_Profile := False;
11181 not Conforming_Types
11182 (Etype (F1), Etype (F2), Type_Conformant)
11184 May_Hide_Profile := False;
11191 if May_Hide_Profile
11195 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11204 -- On exit, we know that S is a new entity
11206 Enter_Overloaded_Entity (S);
11207 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11208 Check_Overriding_Indicator
11209 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11211 -- The Ghost policy in effect at the point of declaration of a parent
11212 -- subprogram and an overriding subprogram must match
11213 -- (SPARK RM 6.9(17)).
11215 Check_Ghost_Overriding (S, Overridden_Subp);
11217 -- Overloading is not allowed in SPARK, except for operators
11219 if Nkind (S) /= N_Defining_Operator_Symbol then
11220 Error_Msg_Sloc := Sloc (Homonym (S));
11221 Check_SPARK_05_Restriction
11222 ("overloading not allowed with entity#", S);
11225 -- If S is a derived operation for an untagged type then by
11226 -- definition it's not a dispatching operation (even if the parent
11227 -- operation was dispatching), so Check_Dispatching_Operation is not
11228 -- called in that case.
11230 if No (Derived_Type)
11231 or else Is_Tagged_Type (Derived_Type)
11233 Check_Dispatching_Operation (S, Empty);
11237 -- If this is a user-defined equality operator that is not a derived
11238 -- subprogram, create the corresponding inequality. If the operation is
11239 -- dispatching, the expansion is done elsewhere, and we do not create
11240 -- an explicit inequality operation.
11242 <<Check_Inequality>>
11243 if Chars (S) = Name_Op_Eq
11244 and then Etype (S) = Standard_Boolean
11245 and then Present (Parent (S))
11246 and then not Is_Dispatching_Operation (S)
11248 Make_Inequality_Operator (S);
11249 Check_Untagged_Equality (S);
11251 end New_Overloaded_Entity;
11253 ---------------------
11254 -- Process_Formals --
11255 ---------------------
11257 procedure Process_Formals
11259 Related_Nod : Node_Id)
11261 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11262 -- Determine whether an access type designates a type coming from a
11265 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11266 -- Check whether the default has a class-wide type. After analysis the
11267 -- default has the type of the formal, so we must also check explicitly
11268 -- for an access attribute.
11270 ----------------------------------
11271 -- Designates_From_Limited_With --
11272 ----------------------------------
11274 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11275 Desig : Entity_Id := Typ;
11278 if Is_Access_Type (Desig) then
11279 Desig := Directly_Designated_Type (Desig);
11282 if Is_Class_Wide_Type (Desig) then
11283 Desig := Root_Type (Desig);
11287 Ekind (Desig) = E_Incomplete_Type
11288 and then From_Limited_With (Desig);
11289 end Designates_From_Limited_With;
11291 ---------------------------
11292 -- Is_Class_Wide_Default --
11293 ---------------------------
11295 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11297 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11298 or else (Nkind (D) = N_Attribute_Reference
11299 and then Attribute_Name (D) = Name_Access
11300 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11301 end Is_Class_Wide_Default;
11305 Context : constant Node_Id := Parent (Parent (T));
11307 Formal : Entity_Id;
11308 Formal_Type : Entity_Id;
11309 Param_Spec : Node_Id;
11312 Num_Out_Params : Nat := 0;
11313 First_Out_Param : Entity_Id := Empty;
11314 -- Used for setting Is_Only_Out_Parameter
11316 -- Start of processing for Process_Formals
11319 -- In order to prevent premature use of the formals in the same formal
11320 -- part, the Ekind is left undefined until all default expressions are
11321 -- analyzed. The Ekind is established in a separate loop at the end.
11323 Param_Spec := First (T);
11324 while Present (Param_Spec) loop
11325 Formal := Defining_Identifier (Param_Spec);
11326 Set_Never_Set_In_Source (Formal, True);
11327 Enter_Name (Formal);
11329 -- Case of ordinary parameters
11331 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11332 Find_Type (Parameter_Type (Param_Spec));
11333 Ptype := Parameter_Type (Param_Spec);
11335 if Ptype = Error then
11339 Formal_Type := Entity (Ptype);
11341 if Is_Incomplete_Type (Formal_Type)
11343 (Is_Class_Wide_Type (Formal_Type)
11344 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11346 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11347 -- primitive operations, as long as their completion is
11348 -- in the same declarative part. If in the private part
11349 -- this means that the type cannot be a Taft-amendment type.
11350 -- Check is done on package exit. For access to subprograms,
11351 -- the use is legal for Taft-amendment types.
11353 -- Ada 2012: tagged incomplete types are allowed as generic
11354 -- formal types. They do not introduce dependencies and the
11355 -- corresponding generic subprogram does not have a delayed
11356 -- freeze, because it does not need a freeze node. However,
11357 -- it is still the case that untagged incomplete types cannot
11358 -- be Taft-amendment types and must be completed in private
11359 -- part, so the subprogram must appear in the list of private
11360 -- dependents of the type.
11362 if Is_Tagged_Type (Formal_Type)
11363 or else (Ada_Version >= Ada_2012
11364 and then not From_Limited_With (Formal_Type)
11365 and then not Is_Generic_Type (Formal_Type))
11367 if Ekind (Scope (Current_Scope)) = E_Package
11368 and then not Is_Generic_Type (Formal_Type)
11369 and then not Is_Class_Wide_Type (Formal_Type)
11372 (Parent (T), N_Access_Function_Definition,
11373 N_Access_Procedure_Definition)
11375 Append_Elmt (Current_Scope,
11376 Private_Dependents (Base_Type (Formal_Type)));
11378 -- Freezing is delayed to ensure that Register_Prim
11379 -- will get called for this operation, which is needed
11380 -- in cases where static dispatch tables aren't built.
11381 -- (Note that the same is done for controlling access
11382 -- parameter cases in function Access_Definition.)
11384 if not Is_Thunk (Current_Scope) then
11385 Set_Has_Delayed_Freeze (Current_Scope);
11390 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11391 N_Access_Procedure_Definition)
11393 -- AI05-0151: Tagged incomplete types are allowed in all
11394 -- formal parts. Untagged incomplete types are not allowed
11395 -- in bodies. Limited views of either kind are not allowed
11396 -- if there is no place at which the non-limited view can
11397 -- become available.
11399 -- Incomplete formal untagged types are not allowed in
11400 -- subprogram bodies (but are legal in their declarations).
11401 -- This excludes bodies created for null procedures, which
11402 -- are basic declarations.
11404 if Is_Generic_Type (Formal_Type)
11405 and then not Is_Tagged_Type (Formal_Type)
11406 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11409 ("invalid use of formal incomplete type", Param_Spec);
11411 elsif Ada_Version >= Ada_2012 then
11412 if Is_Tagged_Type (Formal_Type)
11413 and then (not From_Limited_With (Formal_Type)
11414 or else not In_Package_Body)
11418 elsif Nkind_In (Context, N_Accept_Statement,
11419 N_Accept_Alternative,
11421 or else (Nkind (Context) = N_Subprogram_Body
11422 and then Comes_From_Source (Context))
11425 ("invalid use of untagged incomplete type &",
11426 Ptype, Formal_Type);
11431 ("invalid use of incomplete type&",
11432 Param_Spec, Formal_Type);
11434 -- Further checks on the legality of incomplete types
11435 -- in formal parts are delayed until the freeze point
11436 -- of the enclosing subprogram or access to subprogram.
11440 elsif Ekind (Formal_Type) = E_Void then
11442 ("premature use of&",
11443 Parameter_Type (Param_Spec), Formal_Type);
11446 -- Ada 2012 (AI-142): Handle aliased parameters
11448 if Ada_Version >= Ada_2012
11449 and then Aliased_Present (Param_Spec)
11451 Set_Is_Aliased (Formal);
11454 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11455 -- declaration corresponding to the null-excluding type of the
11456 -- formal in the enclosing scope. Finally, replace the parameter
11457 -- type of the formal with the internal subtype.
11459 if Ada_Version >= Ada_2005
11460 and then Null_Exclusion_Present (Param_Spec)
11462 if not Is_Access_Type (Formal_Type) then
11464 ("`NOT NULL` allowed only for an access type", Param_Spec);
11467 if Can_Never_Be_Null (Formal_Type)
11468 and then Comes_From_Source (Related_Nod)
11471 ("`NOT NULL` not allowed (& already excludes null)",
11472 Param_Spec, Formal_Type);
11476 Create_Null_Excluding_Itype
11478 Related_Nod => Related_Nod,
11479 Scope_Id => Scope (Current_Scope));
11481 -- If the designated type of the itype is an itype that is
11482 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11483 -- on the access subtype, to prevent order-of-elaboration
11484 -- issues in the backend.
11487 -- type T is access procedure;
11488 -- procedure Op (O : not null T);
11490 if Is_Itype (Directly_Designated_Type (Formal_Type))
11492 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11494 Set_Has_Delayed_Freeze (Formal_Type);
11499 -- An access formal type
11503 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11505 -- No need to continue if we already notified errors
11507 if not Present (Formal_Type) then
11511 -- Ada 2005 (AI-254)
11514 AD : constant Node_Id :=
11515 Access_To_Subprogram_Definition
11516 (Parameter_Type (Param_Spec));
11518 if Present (AD) and then Protected_Present (AD) then
11520 Replace_Anonymous_Access_To_Protected_Subprogram
11526 Set_Etype (Formal, Formal_Type);
11528 -- Deal with default expression if present
11530 Default := Expression (Param_Spec);
11532 if Present (Default) then
11533 Check_SPARK_05_Restriction
11534 ("default expression is not allowed", Default);
11536 if Out_Present (Param_Spec) then
11538 ("default initialization only allowed for IN parameters",
11542 -- Do the special preanalysis of the expression (see section on
11543 -- "Handling of Default Expressions" in the spec of package Sem).
11545 Preanalyze_Spec_Expression (Default, Formal_Type);
11547 -- An access to constant cannot be the default for
11548 -- an access parameter that is an access to variable.
11550 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11551 and then not Is_Access_Constant (Formal_Type)
11552 and then Is_Access_Type (Etype (Default))
11553 and then Is_Access_Constant (Etype (Default))
11556 ("formal that is access to variable cannot be initialized "
11557 & "with an access-to-constant expression", Default);
11560 -- Check that the designated type of an access parameter's default
11561 -- is not a class-wide type unless the parameter's designated type
11562 -- is also class-wide.
11564 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11565 and then not Designates_From_Limited_With (Formal_Type)
11566 and then Is_Class_Wide_Default (Default)
11567 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11570 ("access to class-wide expression not allowed here", Default);
11573 -- Check incorrect use of dynamically tagged expressions
11575 if Is_Tagged_Type (Formal_Type) then
11576 Check_Dynamically_Tagged_Expression
11578 Typ => Formal_Type,
11579 Related_Nod => Default);
11583 -- Ada 2005 (AI-231): Static checks
11585 if Ada_Version >= Ada_2005
11586 and then Is_Access_Type (Etype (Formal))
11587 and then Can_Never_Be_Null (Etype (Formal))
11589 Null_Exclusion_Static_Checks (Param_Spec);
11592 -- The following checks are relevant only when SPARK_Mode is on as
11593 -- these are not standard Ada legality rules.
11595 if SPARK_Mode = On then
11596 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11598 -- A function cannot have a parameter of mode IN OUT or OUT
11601 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11603 ("function cannot have parameter of mode `OUT` or "
11604 & "`IN OUT`", Formal);
11607 -- A procedure cannot have an effectively volatile formal
11608 -- parameter of mode IN because it behaves as a constant
11609 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11611 elsif Ekind (Scope (Formal)) = E_Procedure
11612 and then Ekind (Formal) = E_In_Parameter
11613 and then Is_Effectively_Volatile (Formal)
11616 ("formal parameter of mode `IN` cannot be volatile", Formal);
11624 -- If this is the formal part of a function specification, analyze the
11625 -- subtype mark in the context where the formals are visible but not
11626 -- yet usable, and may hide outer homographs.
11628 if Nkind (Related_Nod) = N_Function_Specification then
11629 Analyze_Return_Type (Related_Nod);
11632 -- Now set the kind (mode) of each formal
11634 Param_Spec := First (T);
11635 while Present (Param_Spec) loop
11636 Formal := Defining_Identifier (Param_Spec);
11637 Set_Formal_Mode (Formal);
11639 if Ekind (Formal) = E_In_Parameter then
11640 Set_Default_Value (Formal, Expression (Param_Spec));
11642 if Present (Expression (Param_Spec)) then
11643 Default := Expression (Param_Spec);
11645 if Is_Scalar_Type (Etype (Default)) then
11646 if Nkind (Parameter_Type (Param_Spec)) /=
11647 N_Access_Definition
11649 Formal_Type := Entity (Parameter_Type (Param_Spec));
11653 (Related_Nod, Parameter_Type (Param_Spec));
11656 Apply_Scalar_Range_Check (Default, Formal_Type);
11660 elsif Ekind (Formal) = E_Out_Parameter then
11661 Num_Out_Params := Num_Out_Params + 1;
11663 if Num_Out_Params = 1 then
11664 First_Out_Param := Formal;
11667 elsif Ekind (Formal) = E_In_Out_Parameter then
11668 Num_Out_Params := Num_Out_Params + 1;
11671 -- Skip remaining processing if formal type was in error
11673 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11674 goto Next_Parameter;
11677 -- Force call by reference if aliased
11680 Conv : constant Convention_Id := Convention (Etype (Formal));
11682 if Is_Aliased (Formal) then
11683 Set_Mechanism (Formal, By_Reference);
11685 -- Warn if user asked this to be passed by copy
11687 if Conv = Convention_Ada_Pass_By_Copy then
11689 ("cannot pass aliased parameter & by copy??", Formal);
11692 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11694 elsif Conv = Convention_Ada_Pass_By_Copy then
11695 Set_Mechanism (Formal, By_Copy);
11697 elsif Conv = Convention_Ada_Pass_By_Reference then
11698 Set_Mechanism (Formal, By_Reference);
11706 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11707 Set_Is_Only_Out_Parameter (First_Out_Param);
11709 end Process_Formals;
11711 ----------------------------
11712 -- Reference_Body_Formals --
11713 ----------------------------
11715 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11720 if Error_Posted (Spec) then
11724 -- Iterate over both lists. They may be of different lengths if the two
11725 -- specs are not conformant.
11727 Fs := First_Formal (Spec);
11728 Fb := First_Formal (Bod);
11729 while Present (Fs) and then Present (Fb) loop
11730 Generate_Reference (Fs, Fb, 'b');
11732 if Style_Check then
11733 Style.Check_Identifier (Fb, Fs);
11736 Set_Spec_Entity (Fb, Fs);
11737 Set_Referenced (Fs, False);
11741 end Reference_Body_Formals;
11743 -------------------------
11744 -- Set_Actual_Subtypes --
11745 -------------------------
11747 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11749 Formal : Entity_Id;
11751 First_Stmt : Node_Id := Empty;
11752 AS_Needed : Boolean;
11755 -- If this is an empty initialization procedure, no need to create
11756 -- actual subtypes (small optimization).
11758 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11761 -- Within a predicate function we do not want to generate local
11762 -- subtypes that may generate nested predicate functions.
11764 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11768 -- The subtype declarations may freeze the formals. The body generated
11769 -- for an expression function is not a freeze point, so do not emit
11770 -- these declarations (small loss of efficiency in rare cases).
11772 if Nkind (N) = N_Subprogram_Body
11773 and then Was_Expression_Function (N)
11778 Formal := First_Formal (Subp);
11779 while Present (Formal) loop
11780 T := Etype (Formal);
11782 -- We never need an actual subtype for a constrained formal
11784 if Is_Constrained (T) then
11785 AS_Needed := False;
11787 -- If we have unknown discriminants, then we do not need an actual
11788 -- subtype, or more accurately we cannot figure it out. Note that
11789 -- all class-wide types have unknown discriminants.
11791 elsif Has_Unknown_Discriminants (T) then
11792 AS_Needed := False;
11794 -- At this stage we have an unconstrained type that may need an
11795 -- actual subtype. For sure the actual subtype is needed if we have
11796 -- an unconstrained array type. However, in an instance, the type
11797 -- may appear as a subtype of the full view, while the actual is
11798 -- in fact private (in which case no actual subtype is needed) so
11799 -- check the kind of the base type.
11801 elsif Is_Array_Type (Base_Type (T)) then
11804 -- The only other case needing an actual subtype is an unconstrained
11805 -- record type which is an IN parameter (we cannot generate actual
11806 -- subtypes for the OUT or IN OUT case, since an assignment can
11807 -- change the discriminant values. However we exclude the case of
11808 -- initialization procedures, since discriminants are handled very
11809 -- specially in this context, see the section entitled "Handling of
11810 -- Discriminants" in Einfo.
11812 -- We also exclude the case of Discrim_SO_Functions (functions used
11813 -- in front-end layout mode for size/offset values), since in such
11814 -- functions only discriminants are referenced, and not only are such
11815 -- subtypes not needed, but they cannot always be generated, because
11816 -- of order of elaboration issues.
11818 elsif Is_Record_Type (T)
11819 and then Ekind (Formal) = E_In_Parameter
11820 and then Chars (Formal) /= Name_uInit
11821 and then not Is_Unchecked_Union (T)
11822 and then not Is_Discrim_SO_Function (Subp)
11826 -- All other cases do not need an actual subtype
11829 AS_Needed := False;
11832 -- Generate actual subtypes for unconstrained arrays and
11833 -- unconstrained discriminated records.
11836 if Nkind (N) = N_Accept_Statement then
11838 -- If expansion is active, the formal is replaced by a local
11839 -- variable that renames the corresponding entry of the
11840 -- parameter block, and it is this local variable that may
11841 -- require an actual subtype.
11843 if Expander_Active then
11844 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11846 Decl := Build_Actual_Subtype (T, Formal);
11849 if Present (Handled_Statement_Sequence (N)) then
11851 First (Statements (Handled_Statement_Sequence (N)));
11852 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11853 Mark_Rewrite_Insertion (Decl);
11855 -- If the accept statement has no body, there will be no
11856 -- reference to the actuals, so no need to compute actual
11863 Decl := Build_Actual_Subtype (T, Formal);
11864 Prepend (Decl, Declarations (N));
11865 Mark_Rewrite_Insertion (Decl);
11868 -- The declaration uses the bounds of an existing object, and
11869 -- therefore needs no constraint checks.
11871 Analyze (Decl, Suppress => All_Checks);
11872 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11874 -- We need to freeze manually the generated type when it is
11875 -- inserted anywhere else than in a declarative part.
11877 if Present (First_Stmt) then
11878 Insert_List_Before_And_Analyze (First_Stmt,
11879 Freeze_Entity (Defining_Identifier (Decl), N));
11881 -- Ditto if the type has a dynamic predicate, because the
11882 -- generated function will mention the actual subtype. The
11883 -- predicate may come from an explicit aspect of be inherited.
11885 elsif Has_Predicates (T) then
11886 Insert_List_Before_And_Analyze (Decl,
11887 Freeze_Entity (Defining_Identifier (Decl), N));
11890 if Nkind (N) = N_Accept_Statement
11891 and then Expander_Active
11893 Set_Actual_Subtype (Renamed_Object (Formal),
11894 Defining_Identifier (Decl));
11896 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11900 Next_Formal (Formal);
11902 end Set_Actual_Subtypes;
11904 ---------------------
11905 -- Set_Formal_Mode --
11906 ---------------------
11908 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11909 Spec : constant Node_Id := Parent (Formal_Id);
11910 Id : constant Entity_Id := Scope (Formal_Id);
11913 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11914 -- since we ensure that corresponding actuals are always valid at the
11915 -- point of the call.
11917 if Out_Present (Spec) then
11918 if Ekind_In (Id, E_Entry, E_Entry_Family)
11919 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11921 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11924 if Ekind_In (Id, E_Function, E_Generic_Function) then
11926 -- [IN] OUT parameters allowed for functions in Ada 2012
11928 if Ada_Version >= Ada_2012 then
11930 -- Even in Ada 2012 operators can only have IN parameters
11932 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11933 Error_Msg_N ("operators can only have IN parameters", Spec);
11936 if In_Present (Spec) then
11937 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11939 Set_Ekind (Formal_Id, E_Out_Parameter);
11942 -- But not in earlier versions of Ada
11945 Error_Msg_N ("functions can only have IN parameters", Spec);
11946 Set_Ekind (Formal_Id, E_In_Parameter);
11949 elsif In_Present (Spec) then
11950 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11953 Set_Ekind (Formal_Id, E_Out_Parameter);
11954 Set_Never_Set_In_Source (Formal_Id, True);
11955 Set_Is_True_Constant (Formal_Id, False);
11956 Set_Current_Value (Formal_Id, Empty);
11960 Set_Ekind (Formal_Id, E_In_Parameter);
11963 -- Set Is_Known_Non_Null for access parameters since the language
11964 -- guarantees that access parameters are always non-null. We also set
11965 -- Can_Never_Be_Null, since there is no way to change the value.
11967 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11969 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11970 -- null; In Ada 2005, only if then null_exclusion is explicit.
11972 if Ada_Version < Ada_2005
11973 or else Can_Never_Be_Null (Etype (Formal_Id))
11975 Set_Is_Known_Non_Null (Formal_Id);
11976 Set_Can_Never_Be_Null (Formal_Id);
11979 -- Ada 2005 (AI-231): Null-exclusion access subtype
11981 elsif Is_Access_Type (Etype (Formal_Id))
11982 and then Can_Never_Be_Null (Etype (Formal_Id))
11984 Set_Is_Known_Non_Null (Formal_Id);
11986 -- We can also set Can_Never_Be_Null (thus preventing some junk
11987 -- access checks) for the case of an IN parameter, which cannot
11988 -- be changed, or for an IN OUT parameter, which can be changed but
11989 -- not to a null value. But for an OUT parameter, the initial value
11990 -- passed in can be null, so we can't set this flag in that case.
11992 if Ekind (Formal_Id) /= E_Out_Parameter then
11993 Set_Can_Never_Be_Null (Formal_Id);
11997 Set_Mechanism (Formal_Id, Default_Mechanism);
11998 Set_Formal_Validity (Formal_Id);
11999 end Set_Formal_Mode;
12001 -------------------------
12002 -- Set_Formal_Validity --
12003 -------------------------
12005 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12007 -- If no validity checking, then we cannot assume anything about the
12008 -- validity of parameters, since we do not know there is any checking
12009 -- of the validity on the call side.
12011 if not Validity_Checks_On then
12014 -- If validity checking for parameters is enabled, this means we are
12015 -- not supposed to make any assumptions about argument values.
12017 elsif Validity_Check_Parameters then
12020 -- If we are checking in parameters, we will assume that the caller is
12021 -- also checking parameters, so we can assume the parameter is valid.
12023 elsif Ekind (Formal_Id) = E_In_Parameter
12024 and then Validity_Check_In_Params
12026 Set_Is_Known_Valid (Formal_Id, True);
12028 -- Similar treatment for IN OUT parameters
12030 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12031 and then Validity_Check_In_Out_Params
12033 Set_Is_Known_Valid (Formal_Id, True);
12035 end Set_Formal_Validity;
12037 ------------------------
12038 -- Subtype_Conformant --
12039 ------------------------
12041 function Subtype_Conformant
12042 (New_Id : Entity_Id;
12043 Old_Id : Entity_Id;
12044 Skip_Controlling_Formals : Boolean := False) return Boolean
12048 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12049 Skip_Controlling_Formals => Skip_Controlling_Formals);
12051 end Subtype_Conformant;
12053 ---------------------
12054 -- Type_Conformant --
12055 ---------------------
12057 function Type_Conformant
12058 (New_Id : Entity_Id;
12059 Old_Id : Entity_Id;
12060 Skip_Controlling_Formals : Boolean := False) return Boolean
12064 May_Hide_Profile := False;
12066 (New_Id, Old_Id, Type_Conformant, False, Result,
12067 Skip_Controlling_Formals => Skip_Controlling_Formals);
12069 end Type_Conformant;
12071 -------------------------------
12072 -- Valid_Operator_Definition --
12073 -------------------------------
12075 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12078 Id : constant Name_Id := Chars (Designator);
12082 F := First_Formal (Designator);
12083 while Present (F) loop
12086 if Present (Default_Value (F)) then
12088 ("default values not allowed for operator parameters",
12091 -- For function instantiations that are operators, we must check
12092 -- separately that the corresponding generic only has in-parameters.
12093 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12094 -- an error could not arise in earlier versions of the language.
12096 elsif Ekind (F) /= E_In_Parameter then
12097 Error_Msg_N ("operators can only have IN parameters", F);
12103 -- Verify that user-defined operators have proper number of arguments
12104 -- First case of operators which can only be unary
12106 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12109 -- Case of operators which can be unary or binary
12111 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12112 N_OK := (N in 1 .. 2);
12114 -- All other operators can only be binary
12122 ("incorrect number of arguments for operator", Designator);
12126 and then Base_Type (Etype (Designator)) = Standard_Boolean
12127 and then not Is_Intrinsic_Subprogram (Designator)
12130 ("explicit definition of inequality not allowed", Designator);
12132 end Valid_Operator_Definition;