1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
210 -- Formal_Id is an formal parameter entity. This procedure deals with
211 -- setting the proper validity status for this entity, which depends on
212 -- the kind of parameter and the validity checking mode.
214 ---------------------------------------------
215 -- Analyze_Abstract_Subprogram_Declaration --
216 ---------------------------------------------
218 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
219 Scop : constant Entity_Id := Current_Scope;
220 Subp_Id : constant Entity_Id :=
221 Analyze_Subprogram_Specification (Specification (N));
224 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
226 Generate_Definition (Subp_Id);
228 -- Set the SPARK mode from the current context (may be overwritten later
229 -- with explicit pragma).
231 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
232 Set_SPARK_Pragma_Inherited (Subp_Id);
234 -- Preserve relevant elaboration-related attributes of the context which
235 -- are no longer available or very expensive to recompute once analysis,
236 -- resolution, and expansion are over.
238 Mark_Elaboration_Attributes
242 Set_Is_Abstract_Subprogram (Subp_Id);
243 New_Overloaded_Entity (Subp_Id);
244 Check_Delayed_Subprogram (Subp_Id);
246 Set_Categorization_From_Scope (Subp_Id, Scop);
248 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
249 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
251 -- Issue a warning if the abstract subprogram is neither a dispatching
252 -- operation nor an operation that overrides an inherited subprogram or
253 -- predefined operator, since this most likely indicates a mistake.
255 elsif Warn_On_Redundant_Constructs
256 and then not Is_Dispatching_Operation (Subp_Id)
257 and then not Present (Overridden_Operation (Subp_Id))
258 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
259 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
262 ("abstract subprogram is not dispatching or overriding?r?", N);
265 Generate_Reference_To_Formals (Subp_Id);
266 Check_Eliminated (Subp_Id);
268 if Has_Aspects (N) then
269 Analyze_Aspect_Specifications (N, Subp_Id);
271 end Analyze_Abstract_Subprogram_Declaration;
273 ---------------------------------
274 -- Analyze_Expression_Function --
275 ---------------------------------
277 procedure Analyze_Expression_Function (N : Node_Id) is
278 Expr : constant Node_Id := Expression (N);
279 Loc : constant Source_Ptr := Sloc (N);
280 LocX : constant Source_Ptr := Sloc (Expr);
281 Spec : constant Node_Id := Specification (N);
283 procedure Freeze_Expr_Types (Def_Id : Entity_Id);
284 -- N is an expression function that is a completion and Def_Id its
285 -- defining entity. Freeze before N all the types referenced by the
286 -- expression of the function.
288 -----------------------
289 -- Freeze_Expr_Types --
290 -----------------------
292 procedure Freeze_Expr_Types (Def_Id : Entity_Id) is
293 function Cloned_Expression return Node_Id;
294 -- Build a duplicate of the expression of the return statement that
295 -- has no defining entities shared with the original expression.
297 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result;
298 -- Freeze all types referenced in the subtree rooted at Node
300 -----------------------
301 -- Cloned_Expression --
302 -----------------------
304 function Cloned_Expression return Node_Id is
305 function Clone_Id (Node : Node_Id) return Traverse_Result;
306 -- Tree traversal routine that clones the defining identifier of
307 -- iterator and loop parameter specification nodes.
313 function Clone_Id (Node : Node_Id) return Traverse_Result is
315 if Nkind_In (Node, N_Iterator_Specification,
316 N_Loop_Parameter_Specification)
318 Set_Defining_Identifier (Node,
319 New_Copy (Defining_Identifier (Node)));
325 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id);
329 Dup_Expr : constant Node_Id := New_Copy_Tree (Expr);
331 -- Start of processing for Cloned_Expression
334 -- We must duplicate the expression with semantic information to
335 -- inherit the decoration of global entities in generic instances.
336 -- Set the parent of the new node to be the parent of the original
337 -- to get the proper context, which is needed for complete error
338 -- reporting and for semantic analysis.
340 Set_Parent (Dup_Expr, Parent (Expr));
342 -- Replace the defining identifier of iterators and loop param
343 -- specifications by a clone to ensure that the cloned expression
344 -- and the original expression don't have shared identifiers;
345 -- otherwise, as part of the preanalysis of the expression, these
346 -- shared identifiers may be left decorated with itypes which
347 -- will not be available in the tree passed to the backend.
349 Clone_Def_Ids (Dup_Expr);
352 end Cloned_Expression;
354 ----------------------
355 -- Freeze_Type_Refs --
356 ----------------------
358 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is
359 procedure Check_And_Freeze_Type (Typ : Entity_Id);
360 -- Check that Typ is fully declared and freeze it if so
362 ---------------------------
363 -- Check_And_Freeze_Type --
364 ---------------------------
366 procedure Check_And_Freeze_Type (Typ : Entity_Id) is
368 -- Skip Itypes created by the preanalysis, and itypes whose
369 -- scope is another type (i.e. component subtypes that depend
370 -- on a discriminant),
373 and then (Scope_Within_Or_Same (Scope (Typ), Def_Id)
374 or else Is_Type (Scope (Typ)))
379 -- This provides a better error message than generating
380 -- primitives whose compilation fails much later. Refine
381 -- the error message if possible.
383 Check_Fully_Declared (Typ, Node);
385 if Error_Posted (Node) then
386 if Has_Private_Component (Typ)
387 and then not Is_Private_Type (Typ)
389 Error_Msg_NE ("\type& has private component", Node, Typ);
393 Freeze_Before (N, Typ);
395 end Check_And_Freeze_Type;
397 -- Start of processing for Freeze_Type_Refs
400 -- Check that a type referenced by an entity can be frozen
402 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
403 Check_And_Freeze_Type (Etype (Entity (Node)));
405 -- Check that the enclosing record type can be frozen
407 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
408 Check_And_Freeze_Type (Scope (Entity (Node)));
411 -- Freezing an access type does not freeze the designated type,
412 -- but freezing conversions between access to interfaces requires
413 -- that the interface types themselves be frozen, so that dispatch
414 -- table entities are properly created.
416 -- Unclear whether a more general rule is needed ???
418 elsif Nkind (Node) = N_Type_Conversion
419 and then Is_Access_Type (Etype (Node))
420 and then Is_Interface (Designated_Type (Etype (Node)))
422 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
425 -- An implicit dereference freezes the designated type. In the
426 -- case of a dispatching call whose controlling argument is an
427 -- access type, the dereference is not made explicit, so we must
428 -- check for such a call and freeze the designated type.
430 if Nkind (Node) in N_Has_Etype
431 and then Present (Etype (Node))
432 and then Is_Access_Type (Etype (Node))
433 and then Nkind (Parent (Node)) = N_Function_Call
434 and then Node = Controlling_Argument (Parent (Node))
436 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
439 -- No point in posting several errors on the same expression
441 if Serious_Errors_Detected > 0 then
446 end Freeze_Type_Refs;
448 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs);
452 Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id);
453 Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id);
454 Dup_Expr : constant Node_Id := Cloned_Expression;
456 -- Start of processing for Freeze_Expr_Types
459 -- Preanalyze a duplicate of the expression to have available the
460 -- minimum decoration needed to locate referenced unfrozen types
461 -- without adding any decoration to the function expression.
464 Install_Formals (Def_Id);
466 Preanalyze_Spec_Expression (Dup_Expr, Etype (Def_Id));
469 -- Restore certain attributes of Def_Id since the preanalysis may
470 -- have introduced itypes to this scope, thus modifying attributes
471 -- First_Entity and Last_Entity.
473 Set_First_Entity (Def_Id, Saved_First_Entity);
474 Set_Last_Entity (Def_Id, Saved_Last_Entity);
476 if Present (Last_Entity (Def_Id)) then
477 Set_Next_Entity (Last_Entity (Def_Id), Empty);
480 -- Freeze all types referenced in the expression
482 Freeze_References (Dup_Expr);
483 end Freeze_Expr_Types;
493 Def_Id : Entity_Id := Empty;
495 -- If the expression is a completion, Prev is the entity whose
496 -- declaration is completed. Def_Id is needed to analyze the spec.
498 -- Start of processing for Analyze_Expression_Function
501 -- This is one of the occasions on which we transform the tree during
502 -- semantic analysis. If this is a completion, transform the expression
503 -- function into an equivalent subprogram body, and analyze it.
505 -- Expression functions are inlined unconditionally. The back-end will
506 -- determine whether this is possible.
508 Inline_Processing_Required := True;
510 -- Create a specification for the generated body. This must be done
511 -- prior to the analysis of the initial declaration.
513 New_Spec := Copy_Subprogram_Spec (Spec);
514 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
516 -- If there are previous overloadable entities with the same name,
517 -- check whether any of them is completed by the expression function.
518 -- In a generic context a formal subprogram has no completion.
521 and then Is_Overloadable (Prev)
522 and then not Is_Formal_Subprogram (Prev)
524 Def_Id := Analyze_Subprogram_Specification (Spec);
525 Prev := Find_Corresponding_Spec (N);
527 -- The previous entity may be an expression function as well, in
528 -- which case the redeclaration is illegal.
531 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
532 N_Expression_Function
534 Error_Msg_Sloc := Sloc (Prev);
535 Error_Msg_N ("& conflicts with declaration#", Def_Id);
540 Ret := Make_Simple_Return_Statement (LocX, Expr);
543 Make_Subprogram_Body (Loc,
544 Specification => New_Spec,
545 Declarations => Empty_List,
546 Handled_Statement_Sequence =>
547 Make_Handled_Sequence_Of_Statements (LocX,
548 Statements => New_List (Ret)));
549 Set_Was_Expression_Function (New_Body);
551 -- If the expression completes a generic subprogram, we must create a
552 -- separate node for the body, because at instantiation the original
553 -- node of the generic copy must be a generic subprogram body, and
554 -- cannot be a expression function. Otherwise we just rewrite the
555 -- expression with the non-generic body.
557 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
558 Insert_After (N, New_Body);
560 -- Propagate any aspects or pragmas that apply to the expression
561 -- function to the proper body when the expression function acts
564 if Has_Aspects (N) then
565 Move_Aspects (N, To => New_Body);
568 Relocate_Pragmas_To_Body (New_Body);
570 Rewrite (N, Make_Null_Statement (Loc));
571 Set_Has_Completion (Prev, False);
574 Set_Is_Inlined (Prev);
576 -- If the expression function is a completion, the previous declaration
577 -- must come from source. We know already that it appears in the current
578 -- scope. The entity itself may be internally created if within a body
582 and then Is_Overloadable (Prev)
583 and then not Is_Formal_Subprogram (Prev)
584 and then Comes_From_Source (Parent (Prev))
586 Set_Has_Completion (Prev, False);
587 Set_Is_Inlined (Prev);
589 -- AI12-0103: Expression functions that are a completion freeze their
590 -- expression but don't freeze anything else (unlike regular bodies).
592 -- Note that we cannot defer this freezing to the analysis of the
593 -- expression itself, because a freeze node might appear in a nested
594 -- scope, leading to an elaboration order issue in gigi.
595 -- As elsewhere, we do not emit freeze nodes within a generic unit.
597 if not Inside_A_Generic then
598 Freeze_Expr_Types (Def_Id);
601 -- For navigation purposes, indicate that the function is a body
603 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
604 Rewrite (N, New_Body);
606 -- Remove any existing aspects from the original node because the act
607 -- of rewriting causes the list to be shared between the two nodes.
609 Orig_N := Original_Node (N);
610 Remove_Aspects (Orig_N);
612 -- Propagate any pragmas that apply to expression function to the
613 -- proper body when the expression function acts as a completion.
614 -- Aspects are automatically transfered because of node rewriting.
616 Relocate_Pragmas_To_Body (N);
619 -- Once the aspects of the generated body have been analyzed, create
620 -- a copy for ASIS purposes and associate it with the original node.
622 if Has_Aspects (N) then
623 Set_Aspect_Specifications (Orig_N,
624 New_Copy_List_Tree (Aspect_Specifications (N)));
627 -- Prev is the previous entity with the same name, but it is can
628 -- be an unrelated spec that is not completed by the expression
629 -- function. In that case the relevant entity is the one in the body.
630 -- Not clear that the backend can inline it in this case ???
632 if Has_Completion (Prev) then
634 -- The formals of the expression function are body formals,
635 -- and do not appear in the ali file, which will only contain
636 -- references to the formals of the original subprogram spec.
643 F1 := First_Formal (Def_Id);
644 F2 := First_Formal (Prev);
646 while Present (F1) loop
647 Set_Spec_Entity (F1, F2);
654 Set_Is_Inlined (Defining_Entity (New_Body));
657 -- If this is not a completion, create both a declaration and a body, so
658 -- that the expression can be inlined whenever possible.
661 -- An expression function that is not a completion is not a
662 -- subprogram declaration, and thus cannot appear in a protected
665 if Nkind (Parent (N)) = N_Protected_Definition then
667 ("an expression function is not a legal protected operation", N);
670 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
672 -- Remove any existing aspects from the original node because the act
673 -- of rewriting causes the list to be shared between the two nodes.
675 Orig_N := Original_Node (N);
676 Remove_Aspects (Orig_N);
680 -- Once the aspects of the generated spec have been analyzed, create
681 -- a copy for ASIS purposes and associate it with the original node.
683 if Has_Aspects (N) then
684 Set_Aspect_Specifications (Orig_N,
685 New_Copy_List_Tree (Aspect_Specifications (N)));
688 -- If aspect SPARK_Mode was specified on the body, it needs to be
689 -- repeated both on the generated spec and the body.
691 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
693 if Present (Asp) then
694 Asp := New_Copy_Tree (Asp);
695 Set_Analyzed (Asp, False);
696 Set_Aspect_Specifications (New_Body, New_List (Asp));
699 Def_Id := Defining_Entity (N);
700 Set_Is_Inlined (Def_Id);
702 -- Establish the linkages between the spec and the body. These are
703 -- used when the expression function acts as the prefix of attribute
704 -- 'Access in order to freeze the original expression which has been
705 -- moved to the generated body.
707 Set_Corresponding_Body (N, Defining_Entity (New_Body));
708 Set_Corresponding_Spec (New_Body, Def_Id);
710 -- Within a generic pre-analyze the original expression for name
711 -- capture. The body is also generated but plays no role in
712 -- this because it is not part of the original source.
714 if Inside_A_Generic then
715 Set_Has_Completion (Def_Id);
717 Install_Formals (Def_Id);
718 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
722 -- To prevent premature freeze action, insert the new body at the end
723 -- of the current declarations, or at the end of the package spec.
724 -- However, resolve usage names now, to prevent spurious visibility
725 -- on later entities. Note that the function can now be called in
726 -- the current declarative part, which will appear to be prior to
727 -- the presence of the body in the code. There are nevertheless no
728 -- order of elaboration issues because all name resolution has taken
729 -- place at the point of declaration.
732 Decls : List_Id := List_Containing (N);
733 Expr : constant Node_Id := Expression (Ret);
734 Par : constant Node_Id := Parent (Decls);
735 Typ : constant Entity_Id := Etype (Def_Id);
738 -- If this is a wrapper created for in an instance for a formal
739 -- subprogram, insert body after declaration, to be analyzed when
740 -- the enclosing instance is analyzed.
743 and then Is_Generic_Actual_Subprogram (Def_Id)
745 Insert_After (N, New_Body);
748 if Nkind (Par) = N_Package_Specification
749 and then Decls = Visible_Declarations (Par)
750 and then Present (Private_Declarations (Par))
751 and then not Is_Empty_List (Private_Declarations (Par))
753 Decls := Private_Declarations (Par);
756 Insert_After (Last (Decls), New_Body);
758 -- Preanalyze the expression if not already done above
760 if not Inside_A_Generic then
762 Install_Formals (Def_Id);
763 Preanalyze_Spec_Expression (Expr, Typ);
764 Check_Limited_Return (Original_Node (N), Expr, Typ);
771 -- Check incorrect use of dynamically tagged expression. This doesn't
772 -- fall out automatically when analyzing the generated function body,
773 -- because Check_Dynamically_Tagged_Expression deliberately ignores
774 -- nodes that don't come from source.
777 and then Nkind (Def_Id) in N_Has_Etype
778 and then Is_Tagged_Type (Etype (Def_Id))
780 Check_Dynamically_Tagged_Expression
782 Typ => Etype (Def_Id),
783 Related_Nod => Original_Node (N));
786 -- If the return expression is a static constant, we suppress warning
787 -- messages on unused formals, which in most cases will be noise.
789 Set_Is_Trivial_Subprogram
790 (Defining_Entity (New_Body), Is_OK_Static_Expression (Expr));
791 end Analyze_Expression_Function;
793 ----------------------------------------
794 -- Analyze_Extended_Return_Statement --
795 ----------------------------------------
797 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
799 Check_Compiler_Unit ("extended return statement", N);
800 Analyze_Return_Statement (N);
801 end Analyze_Extended_Return_Statement;
803 ----------------------------
804 -- Analyze_Function_Call --
805 ----------------------------
807 procedure Analyze_Function_Call (N : Node_Id) is
808 Actuals : constant List_Id := Parameter_Associations (N);
809 Func_Nam : constant Node_Id := Name (N);
815 -- A call of the form A.B (X) may be an Ada 2005 call, which is
816 -- rewritten as B (A, X). If the rewriting is successful, the call
817 -- has been analyzed and we just return.
819 if Nkind (Func_Nam) = N_Selected_Component
820 and then Name (N) /= Func_Nam
821 and then Is_Rewrite_Substitution (N)
822 and then Present (Etype (N))
827 -- If error analyzing name, then set Any_Type as result type and return
829 if Etype (Func_Nam) = Any_Type then
830 Set_Etype (N, Any_Type);
834 -- Otherwise analyze the parameters
836 if Present (Actuals) then
837 Actual := First (Actuals);
838 while Present (Actual) loop
840 Check_Parameterless_Call (Actual);
846 end Analyze_Function_Call;
848 -----------------------------
849 -- Analyze_Function_Return --
850 -----------------------------
852 procedure Analyze_Function_Return (N : Node_Id) is
853 Loc : constant Source_Ptr := Sloc (N);
854 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
855 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
857 R_Type : constant Entity_Id := Etype (Scope_Id);
858 -- Function result subtype
860 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
861 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
862 -- aggregate in a return statement.
864 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
865 -- Check that the return_subtype_indication properly matches the result
866 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
868 -----------------------------------
869 -- Check_Aggregate_Accessibility --
870 -----------------------------------
872 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
873 Typ : constant Entity_Id := Etype (Aggr);
880 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
881 Discr := First_Discriminant (Typ);
882 Assoc := First (Component_Associations (Aggr));
883 while Present (Discr) loop
884 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
885 Expr := Expression (Assoc);
887 if Nkind (Expr) = N_Attribute_Reference
888 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
890 Obj := Prefix (Expr);
891 while Nkind_In (Obj, N_Indexed_Component,
892 N_Selected_Component)
897 -- Do not check aliased formals or function calls. A
898 -- run-time check may still be needed ???
900 if Is_Entity_Name (Obj)
901 and then Comes_From_Source (Obj)
903 if Is_Formal (Entity (Obj))
904 and then Is_Aliased (Entity (Obj))
908 elsif Object_Access_Level (Obj) >
909 Scope_Depth (Scope (Scope_Id))
912 ("access discriminant in return aggregate would "
913 & "be a dangling reference", Obj);
919 Next_Discriminant (Discr);
922 end Check_Aggregate_Accessibility;
924 -------------------------------------
925 -- Check_Return_Subtype_Indication --
926 -------------------------------------
928 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
929 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
931 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
932 -- Subtype given in the extended return statement (must match R_Type)
934 Subtype_Ind : constant Node_Id :=
935 Object_Definition (Original_Node (Obj_Decl));
937 procedure Error_No_Match (N : Node_Id);
938 -- Output error messages for case where types do not statically
939 -- match. N is the location for the messages.
945 procedure Error_No_Match (N : Node_Id) is
948 ("subtype must statically match function result subtype", N);
950 if not Predicates_Match (R_Stm_Type, R_Type) then
951 Error_Msg_Node_2 := R_Type;
953 ("\predicate of& does not match predicate of&",
958 -- Start of processing for Check_Return_Subtype_Indication
961 -- First, avoid cascaded errors
963 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
967 -- "return access T" case; check that the return statement also has
968 -- "access T", and that the subtypes statically match:
969 -- if this is an access to subprogram the signatures must match.
971 if Is_Anonymous_Access_Type (R_Type) then
972 if Is_Anonymous_Access_Type (R_Stm_Type) then
973 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
975 if Base_Type (Designated_Type (R_Stm_Type)) /=
976 Base_Type (Designated_Type (R_Type))
977 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
979 Error_No_Match (Subtype_Mark (Subtype_Ind));
983 -- For two anonymous access to subprogram types, the types
984 -- themselves must be type conformant.
986 if not Conforming_Types
987 (R_Stm_Type, R_Type, Fully_Conformant)
989 Error_No_Match (Subtype_Ind);
994 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
997 -- If the return object is of an anonymous access type, then report
998 -- an error if the function's result type is not also anonymous.
1000 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
1001 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
1003 ("anonymous access not allowed for function with named access "
1004 & "result", Subtype_Ind);
1006 -- Subtype indication case: check that the return object's type is
1007 -- covered by the result type, and that the subtypes statically match
1008 -- when the result subtype is constrained. Also handle record types
1009 -- with unknown discriminants for which we have built the underlying
1010 -- record view. Coverage is needed to allow specific-type return
1011 -- objects when the result type is class-wide (see AI05-32).
1013 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
1014 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1017 (Base_Type (R_Type),
1018 Underlying_Record_View (Base_Type (R_Stm_Type))))
1020 -- A null exclusion may be present on the return type, on the
1021 -- function specification, on the object declaration or on the
1024 if Is_Access_Type (R_Type)
1026 (Can_Never_Be_Null (R_Type)
1027 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1028 Can_Never_Be_Null (R_Stm_Type)
1030 Error_No_Match (Subtype_Ind);
1033 -- AI05-103: for elementary types, subtypes must statically match
1035 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1036 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1037 Error_No_Match (Subtype_Ind);
1041 -- All remaining cases are illegal
1043 -- Note: previous versions of this subprogram allowed the return
1044 -- value to be the ancestor of the return type if the return type
1045 -- was a null extension. This was plainly incorrect.
1049 ("wrong type for return_subtype_indication", Subtype_Ind);
1051 end Check_Return_Subtype_Indication;
1053 ---------------------
1054 -- Local Variables --
1055 ---------------------
1058 Obj_Decl : Node_Id := Empty;
1060 -- Start of processing for Analyze_Function_Return
1063 Set_Return_Present (Scope_Id);
1065 if Nkind (N) = N_Simple_Return_Statement then
1066 Expr := Expression (N);
1068 -- Guard against a malformed expression. The parser may have tried to
1069 -- recover but the node is not analyzable.
1071 if Nkind (Expr) = N_Error then
1072 Set_Etype (Expr, Any_Type);
1073 Expander_Mode_Save_And_Set (False);
1077 -- The resolution of a controlled [extension] aggregate associated
1078 -- with a return statement creates a temporary which needs to be
1079 -- finalized on function exit. Wrap the return statement inside a
1080 -- block so that the finalization machinery can detect this case.
1081 -- This early expansion is done only when the return statement is
1082 -- not part of a handled sequence of statements.
1084 if Nkind_In (Expr, N_Aggregate,
1085 N_Extension_Aggregate)
1086 and then Needs_Finalization (R_Type)
1087 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1090 Make_Block_Statement (Loc,
1091 Handled_Statement_Sequence =>
1092 Make_Handled_Sequence_Of_Statements (Loc,
1093 Statements => New_List (Relocate_Node (N)))));
1101 -- Ada 2005 (AI-251): If the type of the returned object is
1102 -- an access to an interface type then we add an implicit type
1103 -- conversion to force the displacement of the "this" pointer to
1104 -- reference the secondary dispatch table. We cannot delay the
1105 -- generation of this implicit conversion until the expansion
1106 -- because in this case the type resolution changes the decoration
1107 -- of the expression node to match R_Type; by contrast, if the
1108 -- returned object is a class-wide interface type then it is too
1109 -- early to generate here the implicit conversion since the return
1110 -- statement may be rewritten by the expander into an extended
1111 -- return statement whose expansion takes care of adding the
1112 -- implicit type conversion to displace the pointer to the object.
1115 and then Serious_Errors_Detected = 0
1116 and then Is_Access_Type (R_Type)
1117 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1118 and then Is_Interface (Designated_Type (R_Type))
1119 and then Is_Progenitor (Designated_Type (R_Type),
1120 Designated_Type (Etype (Expr)))
1122 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1126 Resolve (Expr, R_Type);
1127 Check_Limited_Return (N, Expr, R_Type);
1129 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
1130 Check_Aggregate_Accessibility (Expr);
1134 -- RETURN only allowed in SPARK as the last statement in function
1136 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1138 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1139 or else Present (Next (N)))
1141 Check_SPARK_05_Restriction
1142 ("RETURN should be the last statement in function", N);
1146 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1147 Obj_Decl := Last (Return_Object_Declarations (N));
1149 -- Analyze parts specific to extended_return_statement:
1152 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1153 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1156 Expr := Expression (Obj_Decl);
1158 -- Note: The check for OK_For_Limited_Init will happen in
1159 -- Analyze_Object_Declaration; we treat it as a normal
1160 -- object declaration.
1162 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1165 Check_Return_Subtype_Indication (Obj_Decl);
1167 if Present (HSS) then
1170 if Present (Exception_Handlers (HSS)) then
1172 -- ???Has_Nested_Block_With_Handler needs to be set.
1173 -- Probably by creating an actual N_Block_Statement.
1174 -- Probably in Expand.
1180 -- Mark the return object as referenced, since the return is an
1181 -- implicit reference of the object.
1183 Set_Referenced (Defining_Identifier (Obj_Decl));
1185 Check_References (Stm_Entity);
1187 -- Check RM 6.5 (5.9/3)
1190 if Ada_Version < Ada_2012 then
1192 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1193 -- Can it really happen (extended return???)
1196 ("aliased only allowed for limited return objects "
1197 & "in Ada 2012??", N);
1199 elsif not Is_Limited_View (R_Type) then
1201 ("aliased only allowed for limited return objects", N);
1207 -- Case of Expr present
1209 if Present (Expr) then
1211 -- Defend against previous errors
1213 if Nkind (Expr) = N_Empty
1214 or else No (Etype (Expr))
1219 -- Apply constraint check. Note that this is done before the implicit
1220 -- conversion of the expression done for anonymous access types to
1221 -- ensure correct generation of the null-excluding check associated
1222 -- with null-excluding expressions found in return statements.
1224 Apply_Constraint_Check (Expr, R_Type);
1226 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1227 -- type, apply an implicit conversion of the expression to that type
1228 -- to force appropriate static and run-time accessibility checks.
1230 if Ada_Version >= Ada_2005
1231 and then Ekind (R_Type) = E_Anonymous_Access_Type
1233 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1234 Analyze_And_Resolve (Expr, R_Type);
1236 -- If this is a local anonymous access to subprogram, the
1237 -- accessibility check can be applied statically. The return is
1238 -- illegal if the access type of the return expression is declared
1239 -- inside of the subprogram (except if it is the subtype indication
1240 -- of an extended return statement).
1242 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1243 if not Comes_From_Source (Current_Scope)
1244 or else Ekind (Current_Scope) = E_Return_Statement
1249 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1251 Error_Msg_N ("cannot return local access to subprogram", N);
1254 -- The expression cannot be of a formal incomplete type
1256 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1257 and then Is_Generic_Type (Etype (Expr))
1260 ("cannot return expression of a formal incomplete type", N);
1263 -- If the result type is class-wide, then check that the return
1264 -- expression's type is not declared at a deeper level than the
1265 -- function (RM05-6.5(5.6/2)).
1267 if Ada_Version >= Ada_2005
1268 and then Is_Class_Wide_Type (R_Type)
1270 if Type_Access_Level (Etype (Expr)) >
1271 Subprogram_Access_Level (Scope_Id)
1274 ("level of return expression type is deeper than "
1275 & "class-wide function!", Expr);
1279 -- Check incorrect use of dynamically tagged expression
1281 if Is_Tagged_Type (R_Type) then
1282 Check_Dynamically_Tagged_Expression
1288 -- ??? A real run-time accessibility check is needed in cases
1289 -- involving dereferences of access parameters. For now we just
1290 -- check the static cases.
1292 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1293 and then Is_Limited_View (Etype (Scope_Id))
1294 and then Object_Access_Level (Expr) >
1295 Subprogram_Access_Level (Scope_Id)
1297 -- Suppress the message in a generic, where the rewriting
1300 if Inside_A_Generic then
1305 Make_Raise_Program_Error (Loc,
1306 Reason => PE_Accessibility_Check_Failed));
1309 Error_Msg_Warn := SPARK_Mode /= On;
1310 Error_Msg_N ("cannot return a local value by reference<<", N);
1311 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1315 if Known_Null (Expr)
1316 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1317 and then Null_Exclusion_Present (Parent (Scope_Id))
1319 Apply_Compile_Time_Constraint_Error
1321 Msg => "(Ada 2005) null not allowed for "
1322 & "null-excluding return??",
1323 Reason => CE_Null_Not_Allowed);
1326 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1327 -- has no initializing expression.
1329 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1330 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1331 Subprogram_Access_Level (Scope_Id)
1334 ("level of return expression type is deeper than "
1335 & "class-wide function!", Obj_Decl);
1338 end Analyze_Function_Return;
1340 -------------------------------------
1341 -- Analyze_Generic_Subprogram_Body --
1342 -------------------------------------
1344 procedure Analyze_Generic_Subprogram_Body
1348 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1349 Kind : constant Entity_Kind := Ekind (Gen_Id);
1350 Body_Id : Entity_Id;
1355 -- Copy body and disable expansion while analyzing the generic For a
1356 -- stub, do not copy the stub (which would load the proper body), this
1357 -- will be done when the proper body is analyzed.
1359 if Nkind (N) /= N_Subprogram_Body_Stub then
1360 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1363 -- Once the contents of the generic copy and the template are
1364 -- swapped, do the same for their respective aspect specifications.
1366 Exchange_Aspects (N, New_N);
1368 -- Collect all contract-related source pragmas found within the
1369 -- template and attach them to the contract of the subprogram body.
1370 -- This contract is used in the capture of global references within
1373 Create_Generic_Contract (N);
1378 Spec := Specification (N);
1380 -- Within the body of the generic, the subprogram is callable, and
1381 -- behaves like the corresponding non-generic unit.
1383 Body_Id := Defining_Entity (Spec);
1385 if Kind = E_Generic_Procedure
1386 and then Nkind (Spec) /= N_Procedure_Specification
1388 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1391 elsif Kind = E_Generic_Function
1392 and then Nkind (Spec) /= N_Function_Specification
1394 Error_Msg_N ("invalid body for generic function ", Body_Id);
1398 Set_Corresponding_Body (Gen_Decl, Body_Id);
1400 if Has_Completion (Gen_Id)
1401 and then Nkind (Parent (N)) /= N_Subunit
1403 Error_Msg_N ("duplicate generic body", N);
1406 Set_Has_Completion (Gen_Id);
1409 if Nkind (N) = N_Subprogram_Body_Stub then
1410 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1412 Set_Corresponding_Spec (N, Gen_Id);
1415 if Nkind (Parent (N)) = N_Compilation_Unit then
1416 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1419 -- Make generic parameters immediately visible in the body. They are
1420 -- needed to process the formals declarations. Then make the formals
1421 -- visible in a separate step.
1423 Push_Scope (Gen_Id);
1427 First_Ent : Entity_Id;
1430 First_Ent := First_Entity (Gen_Id);
1433 while Present (E) and then not Is_Formal (E) loop
1438 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1440 -- Now generic formals are visible, and the specification can be
1441 -- analyzed, for subsequent conformance check.
1443 Body_Id := Analyze_Subprogram_Specification (Spec);
1445 -- Make formal parameters visible
1449 -- E is the first formal parameter, we loop through the formals
1450 -- installing them so that they will be visible.
1452 Set_First_Entity (Gen_Id, E);
1453 while Present (E) loop
1459 -- Visible generic entity is callable within its own body
1461 Set_Ekind (Gen_Id, Ekind (Body_Id));
1462 Set_Ekind (Body_Id, E_Subprogram_Body);
1463 Set_Convention (Body_Id, Convention (Gen_Id));
1464 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1465 Set_Scope (Body_Id, Scope (Gen_Id));
1467 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1469 if Nkind (N) = N_Subprogram_Body_Stub then
1471 -- No body to analyze, so restore state of generic unit
1473 Set_Ekind (Gen_Id, Kind);
1474 Set_Ekind (Body_Id, Kind);
1476 if Present (First_Ent) then
1477 Set_First_Entity (Gen_Id, First_Ent);
1484 -- If this is a compilation unit, it must be made visible explicitly,
1485 -- because the compilation of the declaration, unlike other library
1486 -- unit declarations, does not. If it is not a unit, the following
1487 -- is redundant but harmless.
1489 Set_Is_Immediately_Visible (Gen_Id);
1490 Reference_Body_Formals (Gen_Id, Body_Id);
1492 if Is_Child_Unit (Gen_Id) then
1493 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1496 Set_Actual_Subtypes (N, Current_Scope);
1498 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1499 Set_SPARK_Pragma_Inherited (Body_Id);
1501 -- Analyze any aspect specifications that appear on the generic
1504 if Has_Aspects (N) then
1505 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
1508 Analyze_Declarations (Declarations (N));
1511 -- Process the contract of the subprogram body after all declarations
1512 -- have been analyzed. This ensures that any contract-related pragmas
1513 -- are available through the N_Contract node of the body.
1515 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1517 Analyze (Handled_Statement_Sequence (N));
1518 Save_Global_References (Original_Node (N));
1520 -- Prior to exiting the scope, include generic formals again (if any
1521 -- are present) in the set of local entities.
1523 if Present (First_Ent) then
1524 Set_First_Entity (Gen_Id, First_Ent);
1527 Check_References (Gen_Id);
1530 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1531 Update_Use_Clause_Chain;
1532 Validate_Categorization_Dependency (N, Gen_Id);
1534 Check_Subprogram_Order (N);
1536 -- Outside of its body, unit is generic again
1538 Set_Ekind (Gen_Id, Kind);
1539 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1542 Style.Check_Identifier (Body_Id, Gen_Id);
1546 end Analyze_Generic_Subprogram_Body;
1548 ----------------------------
1549 -- Analyze_Null_Procedure --
1550 ----------------------------
1552 procedure Analyze_Null_Procedure
1554 Is_Completion : out Boolean)
1556 Loc : constant Source_Ptr := Sloc (N);
1557 Spec : constant Node_Id := Specification (N);
1558 Designator : Entity_Id;
1560 Null_Body : Node_Id := Empty;
1561 Null_Stmt : Node_Id := Null_Statement (Spec);
1565 -- Capture the profile of the null procedure before analysis, for
1566 -- expansion at the freeze point and at each point of call. The body is
1567 -- used if the procedure has preconditions, or if it is a completion. In
1568 -- the first case the body is analyzed at the freeze point, in the other
1569 -- it replaces the null procedure declaration.
1571 -- For a null procedure that comes from source, a NULL statement is
1572 -- provided by the parser, which carries the source location of the
1573 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1574 -- from expansion, create one now.
1576 if No (Null_Stmt) then
1577 Null_Stmt := Make_Null_Statement (Loc);
1581 Make_Subprogram_Body (Loc,
1582 Specification => New_Copy_Tree (Spec),
1583 Declarations => New_List,
1584 Handled_Statement_Sequence =>
1585 Make_Handled_Sequence_Of_Statements (Loc,
1586 Statements => New_List (Null_Stmt)));
1588 -- Create new entities for body and formals
1590 Set_Defining_Unit_Name (Specification (Null_Body),
1591 Make_Defining_Identifier
1592 (Sloc (Defining_Entity (N)),
1593 Chars (Defining_Entity (N))));
1595 Form := First (Parameter_Specifications (Specification (Null_Body)));
1596 while Present (Form) loop
1597 Set_Defining_Identifier (Form,
1598 Make_Defining_Identifier
1599 (Sloc (Defining_Identifier (Form)),
1600 Chars (Defining_Identifier (Form))));
1604 -- Determine whether the null procedure may be a completion of a generic
1605 -- suprogram, in which case we use the new null body as the completion
1606 -- and set minimal semantic information on the original declaration,
1607 -- which is rewritten as a null statement.
1609 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1611 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1612 Insert_Before (N, Null_Body);
1613 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1615 Rewrite (N, Make_Null_Statement (Loc));
1616 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1617 Is_Completion := True;
1621 -- Resolve the types of the formals now, because the freeze point may
1622 -- appear in a different context, e.g. an instantiation.
1624 Form := First (Parameter_Specifications (Specification (Null_Body)));
1625 while Present (Form) loop
1626 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1627 Find_Type (Parameter_Type (Form));
1629 elsif No (Access_To_Subprogram_Definition
1630 (Parameter_Type (Form)))
1632 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1634 -- The case of a null procedure with a formal that is an
1635 -- access-to-subprogram type, and that is used as an actual
1636 -- in an instantiation is left to the enthusiastic reader.
1646 -- If there are previous overloadable entities with the same name, check
1647 -- whether any of them is completed by the null procedure.
1649 if Present (Prev) and then Is_Overloadable (Prev) then
1650 Designator := Analyze_Subprogram_Specification (Spec);
1651 Prev := Find_Corresponding_Spec (N);
1654 if No (Prev) or else not Comes_From_Source (Prev) then
1655 Designator := Analyze_Subprogram_Specification (Spec);
1656 Set_Has_Completion (Designator);
1658 -- Signal to caller that this is a procedure declaration
1660 Is_Completion := False;
1662 -- Null procedures are always inlined, but generic formal subprograms
1663 -- which appear as such in the internal instance of formal packages,
1664 -- need no completion and are not marked Inline.
1667 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1669 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1670 Set_Body_To_Inline (N, Null_Body);
1671 Set_Is_Inlined (Designator);
1675 -- The null procedure is a completion. We unconditionally rewrite
1676 -- this as a null body (even if expansion is not active), because
1677 -- there are various error checks that are applied on this body
1678 -- when it is analyzed (e.g. correct aspect placement).
1680 if Has_Completion (Prev) then
1681 Error_Msg_Sloc := Sloc (Prev);
1682 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1685 Check_Previous_Null_Procedure (N, Prev);
1687 Is_Completion := True;
1688 Rewrite (N, Null_Body);
1691 end Analyze_Null_Procedure;
1693 -----------------------------
1694 -- Analyze_Operator_Symbol --
1695 -----------------------------
1697 -- An operator symbol such as "+" or "and" may appear in context where the
1698 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1699 -- is just a string, as in (conjunction = "or"). In these cases the parser
1700 -- generates this node, and the semantics does the disambiguation. Other
1701 -- such case are actuals in an instantiation, the generic unit in an
1702 -- instantiation, and pragma arguments.
1704 procedure Analyze_Operator_Symbol (N : Node_Id) is
1705 Par : constant Node_Id := Parent (N);
1708 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1709 or else Nkind (Par) = N_Function_Instantiation
1710 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1711 or else (Nkind (Par) = N_Pragma_Argument_Association
1712 and then not Is_Pragma_String_Literal (Par))
1713 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1714 or else (Nkind (Par) = N_Attribute_Reference
1715 and then Attribute_Name (Par) /= Name_Value)
1717 Find_Direct_Name (N);
1720 Change_Operator_Symbol_To_String_Literal (N);
1723 end Analyze_Operator_Symbol;
1725 -----------------------------------
1726 -- Analyze_Parameter_Association --
1727 -----------------------------------
1729 procedure Analyze_Parameter_Association (N : Node_Id) is
1731 Analyze (Explicit_Actual_Parameter (N));
1732 end Analyze_Parameter_Association;
1734 ----------------------------
1735 -- Analyze_Procedure_Call --
1736 ----------------------------
1738 -- WARNING: This routine manages Ghost regions. Return statements must be
1739 -- replaced by gotos which jump to the end of the routine and restore the
1742 procedure Analyze_Procedure_Call (N : Node_Id) is
1743 procedure Analyze_Call_And_Resolve;
1744 -- Do Analyze and Resolve calls for procedure call. At the end, check
1745 -- for illegal order dependence.
1746 -- ??? where is the check for illegal order dependencies?
1748 ------------------------------
1749 -- Analyze_Call_And_Resolve --
1750 ------------------------------
1752 procedure Analyze_Call_And_Resolve is
1754 if Nkind (N) = N_Procedure_Call_Statement then
1756 Resolve (N, Standard_Void_Type);
1760 end Analyze_Call_And_Resolve;
1764 Actuals : constant List_Id := Parameter_Associations (N);
1765 Loc : constant Source_Ptr := Sloc (N);
1766 P : constant Node_Id := Name (N);
1768 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1769 -- Save the Ghost mode to restore on exit
1774 -- Start of processing for Analyze_Procedure_Call
1777 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1778 -- a procedure call or an entry call. The prefix may denote an access
1779 -- to subprogram type, in which case an implicit dereference applies.
1780 -- If the prefix is an indexed component (without implicit dereference)
1781 -- then the construct denotes a call to a member of an entire family.
1782 -- If the prefix is a simple name, it may still denote a call to a
1783 -- parameterless member of an entry family. Resolution of these various
1784 -- interpretations is delicate.
1786 -- Do not analyze machine code statements to avoid rejecting them in
1789 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1790 Set_Etype (P, Standard_Void_Type);
1795 -- If this is a call of the form Obj.Op, the call may have been analyzed
1796 -- and possibly rewritten into a block, in which case we are done.
1798 if Analyzed (N) then
1801 -- If there is an error analyzing the name (which may have been
1802 -- rewritten if the original call was in prefix notation) then error
1803 -- has been emitted already, mark node and return.
1805 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1806 Set_Etype (N, Any_Type);
1810 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1811 -- Set the mode now to ensure that any nodes generated during analysis
1812 -- and expansion are properly marked as Ghost.
1814 Mark_And_Set_Ghost_Procedure_Call (N);
1816 -- Otherwise analyze the parameters
1818 if Present (Actuals) then
1819 Actual := First (Actuals);
1821 while Present (Actual) loop
1823 Check_Parameterless_Call (Actual);
1828 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1830 if Nkind (P) = N_Attribute_Reference
1831 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1833 Name_Elab_Subp_Body)
1835 if Present (Actuals) then
1837 ("no parameters allowed for this call", First (Actuals));
1841 Set_Etype (N, Standard_Void_Type);
1844 elsif Is_Entity_Name (P)
1845 and then Is_Record_Type (Etype (Entity (P)))
1846 and then Remote_AST_I_Dereference (P)
1850 elsif Is_Entity_Name (P)
1851 and then Ekind (Entity (P)) /= E_Entry_Family
1853 if Is_Access_Type (Etype (P))
1854 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1855 and then No (Actuals)
1856 and then Comes_From_Source (N)
1858 Error_Msg_N ("missing explicit dereference in call", N);
1861 Analyze_Call_And_Resolve;
1863 -- If the prefix is the simple name of an entry family, this is a
1864 -- parameterless call from within the task body itself.
1866 elsif Is_Entity_Name (P)
1867 and then Nkind (P) = N_Identifier
1868 and then Ekind (Entity (P)) = E_Entry_Family
1869 and then Present (Actuals)
1870 and then No (Next (First (Actuals)))
1872 -- Can be call to parameterless entry family. What appears to be the
1873 -- sole argument is in fact the entry index. Rewrite prefix of node
1874 -- accordingly. Source representation is unchanged by this
1878 Make_Indexed_Component (Loc,
1880 Make_Selected_Component (Loc,
1881 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1882 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1883 Expressions => Actuals);
1884 Set_Name (N, New_N);
1885 Set_Etype (New_N, Standard_Void_Type);
1886 Set_Parameter_Associations (N, No_List);
1887 Analyze_Call_And_Resolve;
1889 elsif Nkind (P) = N_Explicit_Dereference then
1890 if Ekind (Etype (P)) = E_Subprogram_Type then
1891 Analyze_Call_And_Resolve;
1893 Error_Msg_N ("expect access to procedure in call", P);
1896 -- The name can be a selected component or an indexed component that
1897 -- yields an access to subprogram. Such a prefix is legal if the call
1898 -- has parameter associations.
1900 elsif Is_Access_Type (Etype (P))
1901 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1903 if Present (Actuals) then
1904 Analyze_Call_And_Resolve;
1906 Error_Msg_N ("missing explicit dereference in call ", N);
1909 -- If not an access to subprogram, then the prefix must resolve to the
1910 -- name of an entry, entry family, or protected operation.
1912 -- For the case of a simple entry call, P is a selected component where
1913 -- the prefix is the task and the selector name is the entry. A call to
1914 -- a protected procedure will have the same syntax. If the protected
1915 -- object contains overloaded operations, the entity may appear as a
1916 -- function, the context will select the operation whose type is Void.
1918 elsif Nkind (P) = N_Selected_Component
1919 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1923 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1924 -- in prefix notation may still be missing its controlling argument,
1925 -- so perform the transformation now.
1927 if SPARK_Mode = On and then In_Inlined_Body then
1929 Subp : constant Entity_Id := Entity (Selector_Name (P));
1930 Typ : constant Entity_Id := Etype (Prefix (P));
1933 if Is_Tagged_Type (Typ)
1934 and then Present (First_Formal (Subp))
1935 and then (Etype (First_Formal (Subp)) = Typ
1937 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1938 and then Try_Object_Operation (P)
1943 Analyze_Call_And_Resolve;
1948 Analyze_Call_And_Resolve;
1951 elsif Nkind (P) = N_Selected_Component
1952 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1953 and then Present (Actuals)
1954 and then No (Next (First (Actuals)))
1956 -- Can be call to parameterless entry family. What appears to be the
1957 -- sole argument is in fact the entry index. Rewrite prefix of node
1958 -- accordingly. Source representation is unchanged by this
1962 Make_Indexed_Component (Loc,
1963 Prefix => New_Copy (P),
1964 Expressions => Actuals);
1965 Set_Name (N, New_N);
1966 Set_Etype (New_N, Standard_Void_Type);
1967 Set_Parameter_Associations (N, No_List);
1968 Analyze_Call_And_Resolve;
1970 -- For the case of a reference to an element of an entry family, P is
1971 -- an indexed component whose prefix is a selected component (task and
1972 -- entry family), and whose index is the entry family index.
1974 elsif Nkind (P) = N_Indexed_Component
1975 and then Nkind (Prefix (P)) = N_Selected_Component
1976 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1978 Analyze_Call_And_Resolve;
1980 -- If the prefix is the name of an entry family, it is a call from
1981 -- within the task body itself.
1983 elsif Nkind (P) = N_Indexed_Component
1984 and then Nkind (Prefix (P)) = N_Identifier
1985 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1988 Make_Selected_Component (Loc,
1990 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1991 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1992 Rewrite (Prefix (P), New_N);
1994 Analyze_Call_And_Resolve;
1996 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1997 -- procedure name, so the construct can only be a qualified expression.
1999 elsif Nkind (P) = N_Qualified_Expression
2000 and then Ada_Version >= Ada_2012
2002 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
2005 -- Anything else is an error
2008 Error_Msg_N ("invalid procedure or entry call", N);
2012 Restore_Ghost_Mode (Saved_GM);
2013 end Analyze_Procedure_Call;
2015 ------------------------------
2016 -- Analyze_Return_Statement --
2017 ------------------------------
2019 procedure Analyze_Return_Statement (N : Node_Id) is
2020 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2021 N_Simple_Return_Statement));
2023 Returns_Object : constant Boolean :=
2024 Nkind (N) = N_Extended_Return_Statement
2026 (Nkind (N) = N_Simple_Return_Statement
2027 and then Present (Expression (N)));
2028 -- True if we're returning something; that is, "return <expression>;"
2029 -- or "return Result : T [:= ...]". False for "return;". Used for error
2030 -- checking: If Returns_Object is True, N should apply to a function
2031 -- body; otherwise N should apply to a procedure body, entry body,
2032 -- accept statement, or extended return statement.
2034 function Find_What_It_Applies_To return Entity_Id;
2035 -- Find the entity representing the innermost enclosing body, accept
2036 -- statement, or extended return statement. If the result is a callable
2037 -- construct or extended return statement, then this will be the value
2038 -- of the Return_Applies_To attribute. Otherwise, the program is
2039 -- illegal. See RM-6.5(4/2).
2041 -----------------------------
2042 -- Find_What_It_Applies_To --
2043 -----------------------------
2045 function Find_What_It_Applies_To return Entity_Id is
2046 Result : Entity_Id := Empty;
2049 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2050 -- and postconditions.
2052 for J in reverse 0 .. Scope_Stack.Last loop
2053 Result := Scope_Stack.Table (J).Entity;
2054 exit when not Ekind_In (Result, E_Block, E_Loop)
2055 and then Chars (Result) /= Name_uPostconditions;
2058 pragma Assert (Present (Result));
2060 end Find_What_It_Applies_To;
2062 -- Local declarations
2064 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2065 Kind : constant Entity_Kind := Ekind (Scope_Id);
2066 Loc : constant Source_Ptr := Sloc (N);
2067 Stm_Entity : constant Entity_Id :=
2069 (E_Return_Statement, Current_Scope, Loc, 'R');
2071 -- Start of processing for Analyze_Return_Statement
2074 Set_Return_Statement_Entity (N, Stm_Entity);
2076 Set_Etype (Stm_Entity, Standard_Void_Type);
2077 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2079 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2080 -- (4/2): an inner return statement will apply to this extended return.
2082 if Nkind (N) = N_Extended_Return_Statement then
2083 Push_Scope (Stm_Entity);
2086 -- Check that pragma No_Return is obeyed. Don't complain about the
2087 -- implicitly-generated return that is placed at the end.
2089 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2090 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2093 -- Warn on any unassigned OUT parameters if in procedure
2095 if Ekind (Scope_Id) = E_Procedure then
2096 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2099 -- Check that functions return objects, and other things do not
2101 if Kind = E_Function or else Kind = E_Generic_Function then
2102 if not Returns_Object then
2103 Error_Msg_N ("missing expression in return from function", N);
2106 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2107 if Returns_Object then
2108 Error_Msg_N ("procedure cannot return value (use function)", N);
2111 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2112 if Returns_Object then
2113 if Is_Protected_Type (Scope (Scope_Id)) then
2114 Error_Msg_N ("entry body cannot return value", N);
2116 Error_Msg_N ("accept statement cannot return value", N);
2120 elsif Kind = E_Return_Statement then
2122 -- We are nested within another return statement, which must be an
2123 -- extended_return_statement.
2125 if Returns_Object then
2126 if Nkind (N) = N_Extended_Return_Statement then
2128 ("extended return statement cannot be nested (use `RETURN;`)",
2131 -- Case of a simple return statement with a value inside extended
2132 -- return statement.
2136 ("return nested in extended return statement cannot return "
2137 & "value (use `RETURN;`)", N);
2142 Error_Msg_N ("illegal context for return statement", N);
2145 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2146 Analyze_Function_Return (N);
2148 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2149 Set_Return_Present (Scope_Id);
2152 if Nkind (N) = N_Extended_Return_Statement then
2156 Kill_Current_Values (Last_Assignment_Only => True);
2157 Check_Unreachable_Code (N);
2159 Analyze_Dimension (N);
2160 end Analyze_Return_Statement;
2162 -------------------------------------
2163 -- Analyze_Simple_Return_Statement --
2164 -------------------------------------
2166 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2168 if Present (Expression (N)) then
2169 Mark_Coextensions (N, Expression (N));
2172 Analyze_Return_Statement (N);
2173 end Analyze_Simple_Return_Statement;
2175 -------------------------
2176 -- Analyze_Return_Type --
2177 -------------------------
2179 procedure Analyze_Return_Type (N : Node_Id) is
2180 Designator : constant Entity_Id := Defining_Entity (N);
2181 Typ : Entity_Id := Empty;
2184 -- Normal case where result definition does not indicate an error
2186 if Result_Definition (N) /= Error then
2187 if Nkind (Result_Definition (N)) = N_Access_Definition then
2188 Check_SPARK_05_Restriction
2189 ("access result is not allowed", Result_Definition (N));
2191 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2194 AD : constant Node_Id :=
2195 Access_To_Subprogram_Definition (Result_Definition (N));
2197 if Present (AD) and then Protected_Present (AD) then
2198 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2200 Typ := Access_Definition (N, Result_Definition (N));
2204 Set_Parent (Typ, Result_Definition (N));
2205 Set_Is_Local_Anonymous_Access (Typ);
2206 Set_Etype (Designator, Typ);
2208 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2210 Null_Exclusion_Static_Checks (N);
2212 -- Subtype_Mark case
2215 Find_Type (Result_Definition (N));
2216 Typ := Entity (Result_Definition (N));
2217 Set_Etype (Designator, Typ);
2219 -- Unconstrained array as result is not allowed in SPARK
2221 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2222 Check_SPARK_05_Restriction
2223 ("returning an unconstrained array is not allowed",
2224 Result_Definition (N));
2227 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2229 Null_Exclusion_Static_Checks (N);
2231 -- If a null exclusion is imposed on the result type, then create
2232 -- a null-excluding itype (an access subtype) and use it as the
2233 -- function's Etype. Note that the null exclusion checks are done
2234 -- right before this, because they don't get applied to types that
2235 -- do not come from source.
2237 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2238 Set_Etype (Designator,
2239 Create_Null_Excluding_Itype
2242 Scope_Id => Scope (Current_Scope)));
2244 -- The new subtype must be elaborated before use because
2245 -- it is visible outside of the function. However its base
2246 -- type may not be frozen yet, so the reference that will
2247 -- force elaboration must be attached to the freezing of
2250 -- If the return specification appears on a proper body,
2251 -- the subtype will have been created already on the spec.
2253 if Is_Frozen (Typ) then
2254 if Nkind (Parent (N)) = N_Subprogram_Body
2255 and then Nkind (Parent (Parent (N))) = N_Subunit
2259 Build_Itype_Reference (Etype (Designator), Parent (N));
2263 Ensure_Freeze_Node (Typ);
2266 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2268 Set_Itype (IR, Etype (Designator));
2269 Append_Freeze_Actions (Typ, New_List (IR));
2274 Set_Etype (Designator, Typ);
2277 if Ekind (Typ) = E_Incomplete_Type
2278 or else (Is_Class_Wide_Type (Typ)
2279 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2281 -- AI05-0151: Tagged incomplete types are allowed in all formal
2282 -- parts. Untagged incomplete types are not allowed in bodies.
2283 -- As a consequence, limited views cannot appear in a basic
2284 -- declaration that is itself within a body, because there is
2285 -- no point at which the non-limited view will become visible.
2287 if Ada_Version >= Ada_2012 then
2288 if From_Limited_With (Typ) and then In_Package_Body then
2290 ("invalid use of incomplete type&",
2291 Result_Definition (N), Typ);
2293 -- The return type of a subprogram body cannot be of a
2294 -- formal incomplete type.
2296 elsif Is_Generic_Type (Typ)
2297 and then Nkind (Parent (N)) = N_Subprogram_Body
2300 ("return type cannot be a formal incomplete type",
2301 Result_Definition (N));
2303 elsif Is_Class_Wide_Type (Typ)
2304 and then Is_Generic_Type (Root_Type (Typ))
2305 and then Nkind (Parent (N)) = N_Subprogram_Body
2308 ("return type cannot be a formal incomplete type",
2309 Result_Definition (N));
2311 elsif Is_Tagged_Type (Typ) then
2314 -- Use is legal in a thunk generated for an operation
2315 -- inherited from a progenitor.
2317 elsif Is_Thunk (Designator)
2318 and then Present (Non_Limited_View (Typ))
2322 elsif Nkind (Parent (N)) = N_Subprogram_Body
2323 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2327 ("invalid use of untagged incomplete type&",
2331 -- The type must be completed in the current package. This
2332 -- is checked at the end of the package declaration when
2333 -- Taft-amendment types are identified. If the return type
2334 -- is class-wide, there is no required check, the type can
2335 -- be a bona fide TAT.
2337 if Ekind (Scope (Current_Scope)) = E_Package
2338 and then In_Private_Part (Scope (Current_Scope))
2339 and then not Is_Class_Wide_Type (Typ)
2341 Append_Elmt (Designator, Private_Dependents (Typ));
2346 ("invalid use of incomplete type&", Designator, Typ);
2351 -- Case where result definition does indicate an error
2354 Set_Etype (Designator, Any_Type);
2356 end Analyze_Return_Type;
2358 -----------------------------
2359 -- Analyze_Subprogram_Body --
2360 -----------------------------
2362 procedure Analyze_Subprogram_Body (N : Node_Id) is
2363 Loc : constant Source_Ptr := Sloc (N);
2364 Body_Spec : constant Node_Id := Specification (N);
2365 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2368 if Debug_Flag_C then
2369 Write_Str ("==> subprogram body ");
2370 Write_Name (Chars (Body_Id));
2371 Write_Str (" from ");
2372 Write_Location (Loc);
2377 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2379 -- The real work is split out into the helper, so it can do "return;"
2380 -- without skipping the debug output:
2382 Analyze_Subprogram_Body_Helper (N);
2384 if Debug_Flag_C then
2386 Write_Str ("<== subprogram body ");
2387 Write_Name (Chars (Body_Id));
2388 Write_Str (" from ");
2389 Write_Location (Loc);
2392 end Analyze_Subprogram_Body;
2394 ------------------------------------
2395 -- Analyze_Subprogram_Body_Helper --
2396 ------------------------------------
2398 -- This procedure is called for regular subprogram bodies, generic bodies,
2399 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2400 -- specification matters, and is used to create a proper declaration for
2401 -- the subprogram, or to perform conformance checks.
2403 -- WARNING: This routine manages Ghost regions. Return statements must be
2404 -- replaced by gotos which jump to the end of the routine and restore the
2407 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2408 Body_Spec : Node_Id := Specification (N);
2409 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2410 Loc : constant Source_Ptr := Sloc (N);
2411 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2413 Conformant : Boolean;
2414 Desig_View : Entity_Id := Empty;
2415 Exch_Views : Elist_Id := No_Elist;
2417 Mask_Types : Elist_Id := No_Elist;
2418 Prot_Typ : Entity_Id := Empty;
2419 Spec_Decl : Node_Id := Empty;
2420 Spec_Id : Entity_Id;
2422 Last_Real_Spec_Entity : Entity_Id := Empty;
2423 -- When we analyze a separate spec, the entity chain ends up containing
2424 -- the formals, as well as any itypes generated during analysis of the
2425 -- default expressions for parameters, or the arguments of associated
2426 -- precondition/postcondition pragmas (which are analyzed in the context
2427 -- of the spec since they have visibility on formals).
2429 -- These entities belong with the spec and not the body. However we do
2430 -- the analysis of the body in the context of the spec (again to obtain
2431 -- visibility to the formals), and all the entities generated during
2432 -- this analysis end up also chained to the entity chain of the spec.
2433 -- But they really belong to the body, and there is circuitry to move
2434 -- them from the spec to the body.
2436 -- However, when we do this move, we don't want to move the real spec
2437 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2438 -- variable points to the last real spec entity, so we only move those
2439 -- chained beyond that point. It is initialized to Empty to deal with
2440 -- the case where there is no separate spec.
2442 function Body_Has_Contract return Boolean;
2443 -- Check whether unanalyzed body has an aspect or pragma that may
2444 -- generate a SPARK contract.
2446 function Body_Has_SPARK_Mode_On return Boolean;
2447 -- Check whether SPARK_Mode On applies to the subprogram body, either
2448 -- because it is specified directly on the body, or because it is
2449 -- inherited from the enclosing subprogram or package.
2451 procedure Build_Subprogram_Declaration;
2452 -- Create a matching subprogram declaration for subprogram body N
2454 procedure Check_Anonymous_Return;
2455 -- Ada 2005: if a function returns an access type that denotes a task,
2456 -- or a type that contains tasks, we must create a master entity for
2457 -- the anonymous type, which typically will be used in an allocator
2458 -- in the body of the function.
2460 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2461 -- Look ahead to recognize a pragma that may appear after the body.
2462 -- If there is a previous spec, check that it appears in the same
2463 -- declarative part. If the pragma is Inline_Always, perform inlining
2464 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2465 -- If the body acts as a spec, and inlining is required, we create a
2466 -- subprogram declaration for it, in order to attach the body to inline.
2467 -- If pragma does not appear after the body, check whether there is
2468 -- an inline pragma before any local declarations.
2470 procedure Check_Missing_Return;
2471 -- Checks for a function with a no return statements, and also performs
2472 -- the warning checks implemented by Check_Returns. In formal mode, also
2473 -- verify that a function ends with a RETURN and that a procedure does
2474 -- not contain any RETURN.
2476 function Disambiguate_Spec return Entity_Id;
2477 -- When a primitive is declared between the private view and the full
2478 -- view of a concurrent type which implements an interface, a special
2479 -- mechanism is used to find the corresponding spec of the primitive
2482 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2483 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2484 -- incomplete types coming from a limited context and replace their
2485 -- limited views with the non-limited ones. Return the list of changes
2486 -- to be used to undo the transformation.
2488 function Is_Private_Concurrent_Primitive
2489 (Subp_Id : Entity_Id) return Boolean;
2490 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2491 -- type that implements an interface and has a private view.
2493 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2494 -- N is the body generated for an expression function that is not a
2495 -- completion and Spec_Id the defining entity of its spec. Mark all
2496 -- the not-yet-frozen types referenced by the simple return statement
2497 -- of the function as formally frozen.
2499 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2500 -- Undo the transformation done by Exchange_Limited_Views.
2502 procedure Set_Trivial_Subprogram (N : Node_Id);
2503 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2504 -- subprogram whose body is being analyzed. N is the statement node
2505 -- causing the flag to be set, if the following statement is a return
2506 -- of an entity, we mark the entity as set in source to suppress any
2507 -- warning on the stylized use of function stubs with a dummy return.
2509 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2510 -- Undo the transformation done by Mask_Unfrozen_Types
2512 procedure Verify_Overriding_Indicator;
2513 -- If there was a previous spec, the entity has been entered in the
2514 -- current scope previously. If the body itself carries an overriding
2515 -- indicator, check that it is consistent with the known status of the
2518 -----------------------
2519 -- Body_Has_Contract --
2520 -----------------------
2522 function Body_Has_Contract return Boolean is
2523 Decls : constant List_Id := Declarations (N);
2527 -- Check for aspects that may generate a contract
2529 if Present (Aspect_Specifications (N)) then
2530 Item := First (Aspect_Specifications (N));
2531 while Present (Item) loop
2532 if Is_Subprogram_Contract_Annotation (Item) then
2540 -- Check for pragmas that may generate a contract
2542 if Present (Decls) then
2543 Item := First (Decls);
2544 while Present (Item) loop
2545 if Nkind (Item) = N_Pragma
2546 and then Is_Subprogram_Contract_Annotation (Item)
2556 end Body_Has_Contract;
2558 ----------------------------
2559 -- Body_Has_SPARK_Mode_On --
2560 ----------------------------
2562 function Body_Has_SPARK_Mode_On return Boolean is
2563 Decls : constant List_Id := Declarations (N);
2567 -- Check for SPARK_Mode aspect
2569 if Present (Aspect_Specifications (N)) then
2570 Item := First (Aspect_Specifications (N));
2571 while Present (Item) loop
2572 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2573 return Get_SPARK_Mode_From_Annotation (Item) = On;
2580 -- Check for SPARK_Mode pragma
2582 if Present (Decls) then
2583 Item := First (Decls);
2584 while Present (Item) loop
2586 -- Pragmas that apply to a subprogram body are usually grouped
2587 -- together. Look for a potential pragma SPARK_Mode among them.
2589 if Nkind (Item) = N_Pragma then
2590 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2591 return Get_SPARK_Mode_From_Annotation (Item) = On;
2594 -- Otherwise the first non-pragma declarative item terminates
2595 -- the region where pragma SPARK_Mode may appear.
2605 -- Otherwise, the applicable SPARK_Mode is inherited from the
2606 -- enclosing subprogram or package.
2608 return SPARK_Mode = On;
2609 end Body_Has_SPARK_Mode_On;
2611 ----------------------------------
2612 -- Build_Subprogram_Declaration --
2613 ----------------------------------
2615 procedure Build_Subprogram_Declaration is
2616 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2617 -- Relocate certain categorization pragmas from the declarative list
2618 -- of subprogram body From and insert them after node To. The pragmas
2621 -- Volatile_Function
2622 -- Also copy pragma SPARK_Mode if present in the declarative list
2623 -- of subprogram body From and insert it after node To. This pragma
2624 -- should not be moved, as it applies to the body too.
2630 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2632 Next_Decl : Node_Id;
2635 pragma Assert (Nkind (From) = N_Subprogram_Body);
2637 -- The destination node must be part of a list, as the pragmas are
2638 -- inserted after it.
2640 pragma Assert (Is_List_Member (To));
2642 -- Inspect the declarations of the subprogram body looking for
2643 -- specific pragmas.
2645 Decl := First (Declarations (N));
2646 while Present (Decl) loop
2647 Next_Decl := Next (Decl);
2649 if Nkind (Decl) = N_Pragma then
2650 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2651 Insert_After (To, New_Copy_Tree (Decl));
2653 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2655 Name_Volatile_Function)
2658 Insert_After (To, Decl);
2669 Subp_Decl : Node_Id;
2671 -- Start of processing for Build_Subprogram_Declaration
2674 -- Create a matching subprogram spec using the profile of the body.
2675 -- The structure of the tree is identical, but has new entities for
2676 -- the defining unit name and formal parameters.
2679 Make_Subprogram_Declaration (Loc,
2680 Specification => Copy_Subprogram_Spec (Body_Spec));
2681 Set_Comes_From_Source (Subp_Decl, True);
2683 -- Relocate the aspects and relevant pragmas from the subprogram body
2684 -- to the generated spec because it acts as the initial declaration.
2686 Insert_Before (N, Subp_Decl);
2687 Move_Aspects (N, To => Subp_Decl);
2688 Move_Pragmas (N, To => Subp_Decl);
2690 -- Ensure that the generated corresponding spec and original body
2691 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2692 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2693 -- correctly set for local subprograms.
2695 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2697 Analyze (Subp_Decl);
2699 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2700 -- the body since the expander may generate calls using that entity.
2701 -- Required to ensure that Expand_Call rewrites calls to this
2702 -- function by calls to the built procedure.
2704 if Modify_Tree_For_C
2705 and then Nkind (Body_Spec) = N_Function_Specification
2707 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2709 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2710 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2711 Corresponding_Procedure
2712 (Defining_Entity (Specification (Subp_Decl))));
2715 -- Analyze any relocated source pragmas or pragmas created for aspect
2718 Decl := Next (Subp_Decl);
2719 while Present (Decl) loop
2721 -- Stop the search for pragmas once the body has been reached as
2722 -- this terminates the region where pragmas may appear.
2727 elsif Nkind (Decl) = N_Pragma then
2734 Spec_Id := Defining_Entity (Subp_Decl);
2735 Set_Corresponding_Spec (N, Spec_Id);
2737 -- Mark the generated spec as a source construct to ensure that all
2738 -- calls to it are properly registered in ALI files for GNATprove.
2740 Set_Comes_From_Source (Spec_Id, True);
2742 -- Ensure that the specs of the subprogram declaration and its body
2743 -- are identical, otherwise they will appear non-conformant due to
2744 -- rewritings in the default values of formal parameters.
2746 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2747 Set_Specification (N, Body_Spec);
2748 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2749 end Build_Subprogram_Declaration;
2751 ----------------------------
2752 -- Check_Anonymous_Return --
2753 ----------------------------
2755 procedure Check_Anonymous_Return is
2761 if Present (Spec_Id) then
2767 if Ekind (Scop) = E_Function
2768 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2769 and then not Is_Thunk (Scop)
2771 -- Skip internally built functions which handle the case of
2772 -- a null access (see Expand_Interface_Conversion)
2774 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2775 and then not Comes_From_Source (Parent (Scop)))
2777 and then (Has_Task (Designated_Type (Etype (Scop)))
2779 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2781 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2782 and then Expander_Active
2784 -- Avoid cases with no tasking support
2786 and then RTE_Available (RE_Current_Master)
2787 and then not Restriction_Active (No_Task_Hierarchy)
2790 Make_Object_Declaration (Loc,
2791 Defining_Identifier =>
2792 Make_Defining_Identifier (Loc, Name_uMaster),
2793 Constant_Present => True,
2794 Object_Definition =>
2795 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2797 Make_Explicit_Dereference (Loc,
2798 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2800 if Present (Declarations (N)) then
2801 Prepend (Decl, Declarations (N));
2803 Set_Declarations (N, New_List (Decl));
2806 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2807 Set_Has_Master_Entity (Scop);
2809 -- Now mark the containing scope as a task master
2812 while Nkind (Par) /= N_Compilation_Unit loop
2813 Par := Parent (Par);
2814 pragma Assert (Present (Par));
2816 -- If we fall off the top, we are at the outer level, and
2817 -- the environment task is our effective master, so nothing
2821 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2823 Set_Is_Task_Master (Par, True);
2828 end Check_Anonymous_Return;
2830 -------------------------
2831 -- Check_Inline_Pragma --
2832 -------------------------
2834 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2838 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2839 -- True when N is a pragma Inline or Inline_Always that applies
2840 -- to this subprogram.
2842 -----------------------
2843 -- Is_Inline_Pragma --
2844 -----------------------
2846 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2848 if Nkind (N) = N_Pragma
2850 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2851 or else (Pragma_Name_Unmapped (N) = Name_Inline
2853 (Front_End_Inlining or else Optimization_Level > 0)))
2854 and then Present (Pragma_Argument_Associations (N))
2857 Pragma_Arg : Node_Id :=
2858 Expression (First (Pragma_Argument_Associations (N)));
2860 if Nkind (Pragma_Arg) = N_Selected_Component then
2861 Pragma_Arg := Selector_Name (Pragma_Arg);
2864 return Chars (Pragma_Arg) = Chars (Body_Id);
2870 end Is_Inline_Pragma;
2872 -- Start of processing for Check_Inline_Pragma
2875 if not Expander_Active then
2879 if Is_List_Member (N)
2880 and then Present (Next (N))
2881 and then Is_Inline_Pragma (Next (N))
2885 elsif Nkind (N) /= N_Subprogram_Body_Stub
2886 and then Present (Declarations (N))
2887 and then Is_Inline_Pragma (First (Declarations (N)))
2889 Prag := First (Declarations (N));
2895 if Present (Prag) then
2896 if Present (Spec_Id) then
2897 if Is_List_Member (N)
2898 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2899 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2905 -- Create a subprogram declaration, to make treatment uniform.
2906 -- Make the sloc of the subprogram name that of the entity in
2907 -- the body, so that style checks find identical strings.
2910 Subp : constant Entity_Id :=
2911 Make_Defining_Identifier
2912 (Sloc (Body_Id), Chars (Body_Id));
2913 Decl : constant Node_Id :=
2914 Make_Subprogram_Declaration (Loc,
2916 New_Copy_Tree (Specification (N)));
2919 -- Link the body and the generated spec
2921 Set_Corresponding_Body (Decl, Body_Id);
2922 Set_Corresponding_Spec (N, Subp);
2924 Set_Defining_Unit_Name (Specification (Decl), Subp);
2926 -- To ensure proper coverage when body is inlined, indicate
2927 -- whether the subprogram comes from source.
2929 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2931 if Present (First_Formal (Body_Id)) then
2932 Plist := Copy_Parameter_List (Body_Id);
2933 Set_Parameter_Specifications
2934 (Specification (Decl), Plist);
2937 -- Move aspects to the new spec
2939 if Has_Aspects (N) then
2940 Move_Aspects (N, To => Decl);
2943 Insert_Before (N, Decl);
2946 Set_Has_Pragma_Inline (Subp);
2948 if Pragma_Name (Prag) = Name_Inline_Always then
2949 Set_Is_Inlined (Subp);
2950 Set_Has_Pragma_Inline_Always (Subp);
2953 -- Prior to copying the subprogram body to create a template
2954 -- for it for subsequent inlining, remove the pragma from
2955 -- the current body so that the copy that will produce the
2956 -- new body will start from a completely unanalyzed tree.
2958 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2959 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2966 end Check_Inline_Pragma;
2968 --------------------------
2969 -- Check_Missing_Return --
2970 --------------------------
2972 procedure Check_Missing_Return is
2974 Missing_Ret : Boolean;
2977 if Nkind (Body_Spec) = N_Function_Specification then
2978 if Present (Spec_Id) then
2984 if Return_Present (Id) then
2985 Check_Returns (HSS, 'F', Missing_Ret);
2988 Set_Has_Missing_Return (Id);
2991 -- Within a premature instantiation of a package with no body, we
2992 -- build completions of the functions therein, with a Raise
2993 -- statement. No point in complaining about a missing return in
2996 elsif Ekind (Id) = E_Function
2997 and then In_Instance
2998 and then Present (Statements (HSS))
2999 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3003 elsif Is_Generic_Subprogram (Id)
3004 or else not Is_Machine_Code_Subprogram (Id)
3006 Error_Msg_N ("missing RETURN statement in function body", N);
3009 -- If procedure with No_Return, check returns
3011 elsif Nkind (Body_Spec) = N_Procedure_Specification
3012 and then Present (Spec_Id)
3013 and then No_Return (Spec_Id)
3015 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
3018 -- Special checks in SPARK mode
3020 if Nkind (Body_Spec) = N_Function_Specification then
3022 -- In SPARK mode, last statement of a function should be a return
3025 Stat : constant Node_Id := Last_Source_Statement (HSS);
3028 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3029 N_Extended_Return_Statement)
3031 Check_SPARK_05_Restriction
3032 ("last statement in function should be RETURN", Stat);
3036 -- In SPARK mode, verify that a procedure has no return
3038 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3039 if Present (Spec_Id) then
3045 -- Would be nice to point to return statement here, can we
3046 -- borrow the Check_Returns procedure here ???
3048 if Return_Present (Id) then
3049 Check_SPARK_05_Restriction
3050 ("procedure should not have RETURN", N);
3053 end Check_Missing_Return;
3055 -----------------------
3056 -- Disambiguate_Spec --
3057 -----------------------
3059 function Disambiguate_Spec return Entity_Id is
3060 Priv_Spec : Entity_Id;
3063 procedure Replace_Types (To_Corresponding : Boolean);
3064 -- Depending on the flag, replace the type of formal parameters of
3065 -- Body_Id if it is a concurrent type implementing interfaces with
3066 -- the corresponding record type or the other way around.
3068 procedure Replace_Types (To_Corresponding : Boolean) is
3070 Formal_Typ : Entity_Id;
3073 Formal := First_Formal (Body_Id);
3074 while Present (Formal) loop
3075 Formal_Typ := Etype (Formal);
3077 if Is_Class_Wide_Type (Formal_Typ) then
3078 Formal_Typ := Root_Type (Formal_Typ);
3081 -- From concurrent type to corresponding record
3083 if To_Corresponding then
3084 if Is_Concurrent_Type (Formal_Typ)
3085 and then Present (Corresponding_Record_Type (Formal_Typ))
3088 (Corresponding_Record_Type (Formal_Typ)))
3091 Corresponding_Record_Type (Formal_Typ));
3094 -- From corresponding record to concurrent type
3097 if Is_Concurrent_Record_Type (Formal_Typ)
3098 and then Present (Interfaces (Formal_Typ))
3101 Corresponding_Concurrent_Type (Formal_Typ));
3105 Next_Formal (Formal);
3109 -- Start of processing for Disambiguate_Spec
3112 -- Try to retrieve the specification of the body as is. All error
3113 -- messages are suppressed because the body may not have a spec in
3114 -- its current state.
3116 Spec_N := Find_Corresponding_Spec (N, False);
3118 -- It is possible that this is the body of a primitive declared
3119 -- between a private and a full view of a concurrent type. The
3120 -- controlling parameter of the spec carries the concurrent type,
3121 -- not the corresponding record type as transformed by Analyze_
3122 -- Subprogram_Specification. In such cases, we undo the change
3123 -- made by the analysis of the specification and try to find the
3126 -- Note that wrappers already have their corresponding specs and
3127 -- bodies set during their creation, so if the candidate spec is
3128 -- a wrapper, then we definitely need to swap all types to their
3129 -- original concurrent status.
3132 or else Is_Primitive_Wrapper (Spec_N)
3134 -- Restore all references of corresponding record types to the
3135 -- original concurrent types.
3137 Replace_Types (To_Corresponding => False);
3138 Priv_Spec := Find_Corresponding_Spec (N, False);
3140 -- The current body truly belongs to a primitive declared between
3141 -- a private and a full view. We leave the modified body as is,
3142 -- and return the true spec.
3144 if Present (Priv_Spec)
3145 and then Is_Private_Primitive (Priv_Spec)
3150 -- In case that this is some sort of error, restore the original
3151 -- state of the body.
3153 Replace_Types (To_Corresponding => True);
3157 end Disambiguate_Spec;
3159 ----------------------------
3160 -- Exchange_Limited_Views --
3161 ----------------------------
3163 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3164 Result : Elist_Id := No_Elist;
3166 procedure Detect_And_Exchange (Id : Entity_Id);
3167 -- Determine whether Id's type denotes an incomplete type associated
3168 -- with a limited with clause and exchange the limited view with the
3169 -- non-limited one when available. Note that the non-limited view
3170 -- may exist because of a with_clause in another unit in the context,
3171 -- but cannot be used because the current view of the enclosing unit
3172 -- is still a limited view.
3174 -------------------------
3175 -- Detect_And_Exchange --
3176 -------------------------
3178 procedure Detect_And_Exchange (Id : Entity_Id) is
3179 Typ : constant Entity_Id := Etype (Id);
3181 if From_Limited_With (Typ)
3182 and then Has_Non_Limited_View (Typ)
3183 and then not From_Limited_With (Scope (Typ))
3186 Result := New_Elmt_List;
3189 Prepend_Elmt (Typ, Result);
3190 Prepend_Elmt (Id, Result);
3191 Set_Etype (Id, Non_Limited_View (Typ));
3193 end Detect_And_Exchange;
3199 -- Start of processing for Exchange_Limited_Views
3202 -- Do not process subprogram bodies as they already use the non-
3203 -- limited view of types.
3205 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3209 -- Examine all formals and swap views when applicable
3211 Formal := First_Formal (Subp_Id);
3212 while Present (Formal) loop
3213 Detect_And_Exchange (Formal);
3215 Next_Formal (Formal);
3218 -- Process the return type of a function
3220 if Ekind (Subp_Id) = E_Function then
3221 Detect_And_Exchange (Subp_Id);
3225 end Exchange_Limited_Views;
3227 -------------------------------------
3228 -- Is_Private_Concurrent_Primitive --
3229 -------------------------------------
3231 function Is_Private_Concurrent_Primitive
3232 (Subp_Id : Entity_Id) return Boolean
3234 Formal_Typ : Entity_Id;
3237 if Present (First_Formal (Subp_Id)) then
3238 Formal_Typ := Etype (First_Formal (Subp_Id));
3240 if Is_Concurrent_Record_Type (Formal_Typ) then
3241 if Is_Class_Wide_Type (Formal_Typ) then
3242 Formal_Typ := Root_Type (Formal_Typ);
3245 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3248 -- The type of the first formal is a concurrent tagged type with
3252 Is_Concurrent_Type (Formal_Typ)
3253 and then Is_Tagged_Type (Formal_Typ)
3254 and then Has_Private_Declaration (Formal_Typ);
3258 end Is_Private_Concurrent_Primitive;
3260 -------------------------
3261 -- Mask_Unfrozen_Types --
3262 -------------------------
3264 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3265 Result : Elist_Id := No_Elist;
3267 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3268 -- Mask all types referenced in the subtree rooted at Node
3270 --------------------
3271 -- Mask_Type_Refs --
3272 --------------------
3274 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3275 procedure Mask_Type (Typ : Entity_Id);
3276 -- ??? what does this do?
3282 procedure Mask_Type (Typ : Entity_Id) is
3284 -- Skip Itypes created by the preanalysis
3287 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3292 if not Is_Frozen (Typ) then
3293 Set_Is_Frozen (Typ);
3294 Append_New_Elmt (Typ, Result);
3298 -- Start of processing for Mask_Type_Refs
3301 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3302 Mask_Type (Etype (Entity (Node)));
3304 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3305 Mask_Type (Scope (Entity (Node)));
3308 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3309 and then Present (Etype (Node))
3311 Mask_Type (Etype (Node));
3317 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3321 Return_Stmt : constant Node_Id :=
3322 First (Statements (Handled_Statement_Sequence (N)));
3324 -- Start of processing for Mask_Unfrozen_Types
3327 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3329 Mask_References (Expression (Return_Stmt));
3332 end Mask_Unfrozen_Types;
3334 ---------------------------
3335 -- Restore_Limited_Views --
3336 ---------------------------
3338 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3339 Elmt : Elmt_Id := First_Elmt (Restore_List);
3343 while Present (Elmt) loop
3346 Set_Etype (Id, Node (Elmt));
3349 end Restore_Limited_Views;
3351 ----------------------------
3352 -- Set_Trivial_Subprogram --
3353 ----------------------------
3355 procedure Set_Trivial_Subprogram (N : Node_Id) is
3356 Nxt : constant Node_Id := Next (N);
3359 Set_Is_Trivial_Subprogram (Body_Id);
3361 if Present (Spec_Id) then
3362 Set_Is_Trivial_Subprogram (Spec_Id);
3366 and then Nkind (Nxt) = N_Simple_Return_Statement
3367 and then No (Next (Nxt))
3368 and then Present (Expression (Nxt))
3369 and then Is_Entity_Name (Expression (Nxt))
3371 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3373 end Set_Trivial_Subprogram;
3375 ---------------------------
3376 -- Unmask_Unfrozen_Types --
3377 ---------------------------
3379 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3380 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3383 while Present (Elmt) loop
3384 Set_Is_Frozen (Node (Elmt), False);
3387 end Unmask_Unfrozen_Types;
3389 ---------------------------------
3390 -- Verify_Overriding_Indicator --
3391 ---------------------------------
3393 procedure Verify_Overriding_Indicator is
3395 if Must_Override (Body_Spec) then
3396 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3397 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3401 elsif not Present (Overridden_Operation (Spec_Id)) then
3403 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3405 -- Overriding indicators aren't allowed for protected subprogram
3406 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3407 -- this to a warning if -gnatd.E is enabled.
3409 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3410 Error_Msg_Warn := Error_To_Warning;
3412 ("<<overriding indicator not allowed for protected "
3413 & "subprogram body", Body_Spec);
3416 elsif Must_Not_Override (Body_Spec) then
3417 if Present (Overridden_Operation (Spec_Id)) then
3419 ("subprogram& overrides inherited operation",
3420 Body_Spec, Spec_Id);
3422 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3423 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3426 ("subprogram& overrides predefined operator ",
3427 Body_Spec, Spec_Id);
3429 -- Overriding indicators aren't allowed for protected subprogram
3430 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3431 -- this to a warning if -gnatd.E is enabled.
3433 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3434 Error_Msg_Warn := Error_To_Warning;
3437 ("<<overriding indicator not allowed "
3438 & "for protected subprogram body", Body_Spec);
3440 -- If this is not a primitive operation, then the overriding
3441 -- indicator is altogether illegal.
3443 elsif not Is_Primitive (Spec_Id) then
3445 ("overriding indicator only allowed "
3446 & "if subprogram is primitive", Body_Spec);
3449 -- If checking the style rule and the operation overrides, then
3450 -- issue a warning about a missing overriding_indicator. Protected
3451 -- subprogram bodies are excluded from this style checking, since
3452 -- they aren't primitives (even though their declarations can
3453 -- override) and aren't allowed to have an overriding_indicator.
3456 and then Present (Overridden_Operation (Spec_Id))
3457 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3459 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3460 Style.Missing_Overriding (N, Body_Id);
3463 and then Can_Override_Operator (Spec_Id)
3464 and then not In_Predefined_Unit (Spec_Id)
3466 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3467 Style.Missing_Overriding (N, Body_Id);
3469 end Verify_Overriding_Indicator;
3473 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3474 Saved_ISMP : constant Boolean :=
3475 Ignore_SPARK_Mode_Pragmas_In_Instance;
3476 -- Save the Ghost and SPARK mode-related data to restore on exit
3478 -- Start of processing for Analyze_Subprogram_Body_Helper
3481 -- A [generic] subprogram body freezes the contract of the nearest
3482 -- enclosing package body and all other contracts encountered in the
3483 -- same declarative part up to and excluding the subprogram body:
3485 -- package body Nearest_Enclosing_Package
3486 -- with Refined_State => (State => Constit)
3490 -- procedure Freezes_Enclosing_Package_Body
3491 -- with Refined_Depends => (Input => Constit) ...
3493 -- This ensures that any annotations referenced by the contract of the
3494 -- [generic] subprogram body are available. This form of freezing is
3495 -- decoupled from the usual Freeze_xxx mechanism because it must also
3496 -- work in the context of generics where normal freezing is disabled.
3498 -- Only bodies coming from source should cause this type of freezing.
3499 -- Expression functions that act as bodies and complete an initial
3500 -- declaration must be included in this category, hence the use of
3503 if Comes_From_Source (Original_Node (N)) then
3504 Freeze_Previous_Contracts (N);
3507 -- Generic subprograms are handled separately. They always have a
3508 -- generic specification. Determine whether current scope has a
3509 -- previous declaration.
3511 -- If the subprogram body is defined within an instance of the same
3512 -- name, the instance appears as a package renaming, and will be hidden
3513 -- within the subprogram.
3515 if Present (Prev_Id)
3516 and then not Is_Overloadable (Prev_Id)
3517 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3518 or else Comes_From_Source (Prev_Id))
3520 if Is_Generic_Subprogram (Prev_Id) then
3523 -- A subprogram body is Ghost when it is stand alone and subject
3524 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3525 -- the mode now to ensure that any nodes generated during analysis
3526 -- and expansion are properly marked as Ghost.
3528 Mark_And_Set_Ghost_Body (N, Spec_Id);
3530 -- If the body completes the initial declaration of a compilation
3531 -- unit which is subject to pragma Elaboration_Checks, set the
3532 -- model specified by the pragma because it applies to all parts
3535 Install_Elaboration_Model (Spec_Id);
3537 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3538 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3540 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3542 if Nkind (N) = N_Subprogram_Body then
3543 HSS := Handled_Statement_Sequence (N);
3544 Check_Missing_Return;
3549 -- Otherwise a previous entity conflicts with the subprogram name.
3550 -- Attempting to enter name will post error.
3553 Enter_Name (Body_Id);
3557 -- Non-generic case, find the subprogram declaration, if one was seen,
3558 -- or enter new overloaded entity in the current scope. If the
3559 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3560 -- part of the context of one of its subunits. No need to redo the
3563 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3567 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3569 if Nkind (N) = N_Subprogram_Body_Stub
3570 or else No (Corresponding_Spec (N))
3572 if Is_Private_Concurrent_Primitive (Body_Id) then
3573 Spec_Id := Disambiguate_Spec;
3575 -- A subprogram body is Ghost when it is stand alone and
3576 -- subject to pragma Ghost or when the corresponding spec is
3577 -- Ghost. Set the mode now to ensure that any nodes generated
3578 -- during analysis and expansion are properly marked as Ghost.
3580 Mark_And_Set_Ghost_Body (N, Spec_Id);
3582 -- If the body completes a compilation unit which is subject
3583 -- to pragma Elaboration_Checks, set the model specified by
3584 -- the pragma because it applies to all parts of the unit.
3586 Install_Elaboration_Model (Spec_Id);
3589 Spec_Id := Find_Corresponding_Spec (N);
3591 -- A subprogram body is Ghost when it is stand alone and
3592 -- subject to pragma Ghost or when the corresponding spec is
3593 -- Ghost. Set the mode now to ensure that any nodes generated
3594 -- during analysis and expansion are properly marked as Ghost.
3596 Mark_And_Set_Ghost_Body (N, Spec_Id);
3598 -- If the body completes a compilation unit which is subject
3599 -- to pragma Elaboration_Checks, set the model specified by
3600 -- the pragma because it applies to all parts of the unit.
3602 Install_Elaboration_Model (Spec_Id);
3604 -- In GNATprove mode, if the body has no previous spec, create
3605 -- one so that the inlining machinery can operate properly.
3606 -- Transfer aspects, if any, to the new spec, so that they
3607 -- are legal and can be processed ahead of the body.
3608 -- We make two copies of the given spec, one for the new
3609 -- declaration, and one for the body.
3611 if No (Spec_Id) and then GNATprove_Mode
3613 -- Inlining does not apply during pre-analysis of code
3615 and then Full_Analysis
3617 -- Inlining only applies to full bodies, not stubs
3619 and then Nkind (N) /= N_Subprogram_Body_Stub
3621 -- Inlining only applies to bodies in the source code, not to
3622 -- those generated by the compiler. In particular, expression
3623 -- functions, whose body is generated by the compiler, are
3624 -- treated specially by GNATprove.
3626 and then Comes_From_Source (Body_Id)
3628 -- This cannot be done for a compilation unit, which is not
3629 -- in a context where we can insert a new spec.
3631 and then Is_List_Member (N)
3633 -- Inlining only applies to subprograms without contracts,
3634 -- as a contract is a sign that GNATprove should perform a
3635 -- modular analysis of the subprogram instead of a contextual
3636 -- analysis at each call site. The same test is performed in
3637 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3638 -- here in another form (because the contract has not been
3639 -- attached to the body) to avoid front-end errors in case
3640 -- pragmas are used instead of aspects, because the
3641 -- corresponding pragmas in the body would not be transferred
3642 -- to the spec, leading to legality errors.
3644 and then not Body_Has_Contract
3645 and then not Inside_A_Generic
3647 Build_Subprogram_Declaration;
3649 -- If this is a function that returns a constrained array, and
3650 -- we are generating SPARK_For_C, create subprogram declaration
3651 -- to simplify subsequent C generation.
3654 and then Modify_Tree_For_C
3655 and then Nkind (Body_Spec) = N_Function_Specification
3656 and then Is_Array_Type (Etype (Body_Id))
3657 and then Is_Constrained (Etype (Body_Id))
3659 Build_Subprogram_Declaration;
3663 -- If this is a duplicate body, no point in analyzing it
3665 if Error_Posted (N) then
3669 -- A subprogram body should cause freezing of its own declaration,
3670 -- but if there was no previous explicit declaration, then the
3671 -- subprogram will get frozen too late (there may be code within
3672 -- the body that depends on the subprogram having been frozen,
3673 -- such as uses of extra formals), so we force it to be frozen
3674 -- here. Same holds if the body and spec are compilation units.
3675 -- Finally, if the return type is an anonymous access to protected
3676 -- subprogram, it must be frozen before the body because its
3677 -- expansion has generated an equivalent type that is used when
3678 -- elaborating the body.
3680 -- An exception in the case of Ada 2012, AI05-177: The bodies
3681 -- created for expression functions do not freeze.
3684 and then Nkind (Original_Node (N)) /= N_Expression_Function
3686 Freeze_Before (N, Body_Id);
3688 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3689 Freeze_Before (N, Spec_Id);
3691 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3692 Freeze_Before (N, Etype (Body_Id));
3696 Spec_Id := Corresponding_Spec (N);
3698 -- A subprogram body is Ghost when it is stand alone and subject
3699 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3700 -- the mode now to ensure that any nodes generated during analysis
3701 -- and expansion are properly marked as Ghost.
3703 Mark_And_Set_Ghost_Body (N, Spec_Id);
3705 -- If the body completes the initial declaration of a compilation
3706 -- unit which is subject to pragma Elaboration_Checks, set the
3707 -- model specified by the pragma because it applies to all parts
3710 Install_Elaboration_Model (Spec_Id);
3714 -- Previously we scanned the body to look for nested subprograms, and
3715 -- rejected an inline directive if nested subprograms were present,
3716 -- because the back-end would generate conflicting symbols for the
3717 -- nested bodies. This is now unnecessary.
3719 -- Look ahead to recognize a pragma Inline that appears after the body
3721 Check_Inline_Pragma (Spec_Id);
3723 -- Deal with special case of a fully private operation in the body of
3724 -- the protected type. We must create a declaration for the subprogram,
3725 -- in order to attach the protected subprogram that will be used in
3726 -- internal calls. We exclude compiler generated bodies from the
3727 -- expander since the issue does not arise for those cases.
3730 and then Comes_From_Source (N)
3731 and then Is_Protected_Type (Current_Scope)
3733 Spec_Id := Build_Private_Protected_Declaration (N);
3736 -- If we are generating C and this is a function returning a constrained
3737 -- array type for which we must create a procedure with an extra out
3738 -- parameter, build and analyze the body now. The procedure declaration
3739 -- has already been created. We reuse the source body of the function,
3740 -- because in an instance it may contain global references that cannot
3741 -- be reanalyzed. The source function itself is not used any further,
3742 -- so we mark it as having a completion. If the subprogram is a stub the
3743 -- transformation is done later, when the proper body is analyzed.
3746 and then Modify_Tree_For_C
3747 and then Present (Spec_Id)
3748 and then Ekind (Spec_Id) = E_Function
3749 and then Nkind (N) /= N_Subprogram_Body_Stub
3750 and then Rewritten_For_C (Spec_Id)
3752 Set_Has_Completion (Spec_Id);
3754 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3757 -- The entity for the created procedure must remain invisible, so it
3758 -- does not participate in resolution of subsequent references to the
3761 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3765 -- If a separate spec is present, then deal with freezing issues
3767 if Present (Spec_Id) then
3768 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3769 Verify_Overriding_Indicator;
3771 -- In general, the spec will be frozen when we start analyzing the
3772 -- body. However, for internally generated operations, such as
3773 -- wrapper functions for inherited operations with controlling
3774 -- results, the spec may not have been frozen by the time we expand
3775 -- the freeze actions that include the bodies. In particular, extra
3776 -- formals for accessibility or for return-in-place may need to be
3777 -- generated. Freeze nodes, if any, are inserted before the current
3778 -- body. These freeze actions are also needed in ASIS mode and in
3779 -- Compile_Only mode to enable the proper back-end type annotations.
3780 -- They are necessary in any case to insure order of elaboration
3783 if not Is_Frozen (Spec_Id)
3784 and then (Expander_Active
3786 or else (Operating_Mode = Check_Semantics
3787 and then Serious_Errors_Detected = 0))
3789 -- The body generated for an expression function that is not a
3790 -- completion is a freeze point neither for the profile nor for
3791 -- anything else. That's why, in order to prevent any freezing
3792 -- during analysis, we need to mask types declared outside the
3793 -- expression that are not yet frozen.
3795 if Nkind (N) = N_Subprogram_Body
3796 and then Was_Expression_Function (N)
3797 and then not Has_Completion (Spec_Id)
3799 Set_Is_Frozen (Spec_Id);
3800 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3802 Set_Has_Delayed_Freeze (Spec_Id);
3803 Freeze_Before (N, Spec_Id);
3808 -- If the subprogram has a class-wide clone, build its body as a copy
3809 -- of the original body, and rewrite body of original subprogram as a
3810 -- wrapper that calls the clone.
3812 if Present (Spec_Id)
3813 and then Present (Class_Wide_Clone (Spec_Id))
3814 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3816 Build_Class_Wide_Clone_Body (Spec_Id, N);
3818 -- This is the new body for the existing primitive operation
3820 Rewrite (N, Build_Class_Wide_Clone_Call
3821 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3822 Set_Has_Completion (Spec_Id, False);
3827 -- Place subprogram on scope stack, and make formals visible. If there
3828 -- is a spec, the visible entity remains that of the spec.
3830 if Present (Spec_Id) then
3831 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3833 if Is_Child_Unit (Spec_Id) then
3834 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3838 Style.Check_Identifier (Body_Id, Spec_Id);
3841 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3842 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3844 if Is_Abstract_Subprogram (Spec_Id) then
3845 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3849 Set_Convention (Body_Id, Convention (Spec_Id));
3850 Set_Has_Completion (Spec_Id);
3852 if Is_Protected_Type (Scope (Spec_Id)) then
3853 Prot_Typ := Scope (Spec_Id);
3856 -- If this is a body generated for a renaming, do not check for
3857 -- full conformance. The check is redundant, because the spec of
3858 -- the body is a copy of the spec in the renaming declaration,
3859 -- and the test can lead to spurious errors on nested defaults.
3861 if Present (Spec_Decl)
3862 and then not Comes_From_Source (N)
3864 (Nkind (Original_Node (Spec_Decl)) =
3865 N_Subprogram_Renaming_Declaration
3866 or else (Present (Corresponding_Body (Spec_Decl))
3868 Nkind (Unit_Declaration_Node
3869 (Corresponding_Body (Spec_Decl))) =
3870 N_Subprogram_Renaming_Declaration))
3874 -- Conversely, the spec may have been generated for specless body
3875 -- with an inline pragma. The entity comes from source, which is
3876 -- both semantically correct and necessary for proper inlining.
3877 -- The subprogram declaration itself is not in the source.
3879 elsif Comes_From_Source (N)
3880 and then Present (Spec_Decl)
3881 and then not Comes_From_Source (Spec_Decl)
3882 and then Has_Pragma_Inline (Spec_Id)
3889 Fully_Conformant, True, Conformant, Body_Id);
3892 -- If the body is not fully conformant, we have to decide if we
3893 -- should analyze it or not. If it has a really messed up profile
3894 -- then we probably should not analyze it, since we will get too
3895 -- many bogus messages.
3897 -- Our decision is to go ahead in the non-fully conformant case
3898 -- only if it is at least mode conformant with the spec. Note
3899 -- that the call to Check_Fully_Conformant has issued the proper
3900 -- error messages to complain about the lack of conformance.
3903 and then not Mode_Conformant (Body_Id, Spec_Id)
3909 if Spec_Id /= Body_Id then
3910 Reference_Body_Formals (Spec_Id, Body_Id);
3913 Set_Ekind (Body_Id, E_Subprogram_Body);
3915 if Nkind (N) = N_Subprogram_Body_Stub then
3916 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3921 Set_Corresponding_Spec (N, Spec_Id);
3923 -- Ada 2005 (AI-345): If the operation is a primitive operation
3924 -- of a concurrent type, the type of the first parameter has been
3925 -- replaced with the corresponding record, which is the proper
3926 -- run-time structure to use. However, within the body there may
3927 -- be uses of the formals that depend on primitive operations
3928 -- of the type (in particular calls in prefixed form) for which
3929 -- we need the original concurrent type. The operation may have
3930 -- several controlling formals, so the replacement must be done
3933 if Comes_From_Source (Spec_Id)
3934 and then Present (First_Entity (Spec_Id))
3935 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3936 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3937 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3938 and then Present (Corresponding_Concurrent_Type
3939 (Etype (First_Entity (Spec_Id))))
3942 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3946 Form := First_Formal (Spec_Id);
3947 while Present (Form) loop
3948 if Etype (Form) = Typ then
3949 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3957 -- Make the formals visible, and place subprogram on scope stack.
3958 -- This is also the point at which we set Last_Real_Spec_Entity
3959 -- to mark the entities which will not be moved to the body.
3961 Install_Formals (Spec_Id);
3962 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3964 -- Within an instance, add local renaming declarations so that
3965 -- gdb can retrieve the values of actuals more easily. This is
3966 -- only relevant if generating code (and indeed we definitely
3967 -- do not want these definitions -gnatc mode, because that would
3970 if Is_Generic_Instance (Spec_Id)
3971 and then Is_Wrapper_Package (Current_Scope)
3972 and then Expander_Active
3974 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3977 Push_Scope (Spec_Id);
3979 -- Make sure that the subprogram is immediately visible. For
3980 -- child units that have no separate spec this is indispensable.
3981 -- Otherwise it is safe albeit redundant.
3983 Set_Is_Immediately_Visible (Spec_Id);
3986 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3987 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3988 Set_Scope (Body_Id, Scope (Spec_Id));
3990 -- Case of subprogram body with no previous spec
3993 -- Check for style warning required
3997 -- Only apply check for source level subprograms for which checks
3998 -- have not been suppressed.
4000 and then Comes_From_Source (Body_Id)
4001 and then not Suppress_Style_Checks (Body_Id)
4003 -- No warnings within an instance
4005 and then not In_Instance
4007 -- No warnings for expression functions
4009 and then Nkind (Original_Node (N)) /= N_Expression_Function
4011 Style.Body_With_No_Spec (N);
4014 New_Overloaded_Entity (Body_Id);
4016 if Nkind (N) /= N_Subprogram_Body_Stub then
4017 Set_Acts_As_Spec (N);
4018 Generate_Definition (Body_Id);
4020 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
4022 -- If the body is an entry wrapper created for an entry with
4023 -- preconditions, it must be compiled in the context of the
4024 -- enclosing synchronized object, because it may mention other
4025 -- operations of the type.
4027 if Is_Entry_Wrapper (Body_Id) then
4029 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4032 Install_Declarations (Prot);
4036 Install_Formals (Body_Id);
4038 Push_Scope (Body_Id);
4041 -- For stubs and bodies with no previous spec, generate references to
4044 Generate_Reference_To_Formals (Body_Id);
4047 -- Entry barrier functions are generated outside the protected type and
4048 -- should not carry the SPARK_Mode of the enclosing context.
4050 if Nkind (N) = N_Subprogram_Body
4051 and then Is_Entry_Barrier_Function (N)
4055 -- The body is generated as part of expression function expansion. When
4056 -- the expression function appears in the visible declarations of a
4057 -- package, the body is added to the private declarations. Since both
4058 -- declarative lists may be subject to a different SPARK_Mode, inherit
4059 -- the mode of the spec.
4061 -- package P with SPARK_Mode is
4062 -- function Expr_Func ... is (...); -- original
4063 -- [function Expr_Func ...;] -- generated spec
4066 -- pragma SPARK_Mode (Off);
4067 -- [function Expr_Func ... is return ...;] -- generated body
4068 -- end P; -- mode is ON
4070 elsif not Comes_From_Source (N)
4071 and then Present (Spec_Id)
4072 and then Is_Expression_Function (Spec_Id)
4074 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4075 Set_SPARK_Pragma_Inherited
4076 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4078 -- Set the SPARK_Mode from the current context (may be overwritten later
4079 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4080 -- initially on a stand-alone subprogram body, but is then relocated to
4081 -- a generated corresponding spec. In this scenario the mode is shared
4082 -- between the spec and body.
4084 elsif No (SPARK_Pragma (Body_Id)) then
4085 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4086 Set_SPARK_Pragma_Inherited (Body_Id);
4089 -- A subprogram body may be instantiated or inlined at a later pass.
4090 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4091 -- applied to the initial declaration of the body.
4093 if Present (Spec_Id) then
4094 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4095 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4099 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4100 -- case the body is instantiated or inlined later and out of context.
4101 -- The body uses this attribute to restore the value of the global
4104 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4105 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4107 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4108 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4112 -- If this is the proper body of a stub, we must verify that the stub
4113 -- conforms to the body, and to the previous spec if one was present.
4114 -- We know already that the body conforms to that spec. This test is
4115 -- only required for subprograms that come from source.
4117 if Nkind (Parent (N)) = N_Subunit
4118 and then Comes_From_Source (N)
4119 and then not Error_Posted (Body_Id)
4120 and then Nkind (Corresponding_Stub (Parent (N))) =
4121 N_Subprogram_Body_Stub
4124 Old_Id : constant Entity_Id :=
4126 (Specification (Corresponding_Stub (Parent (N))));
4128 Conformant : Boolean := False;
4131 if No (Spec_Id) then
4132 Check_Fully_Conformant (Body_Id, Old_Id);
4136 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4138 if not Conformant then
4140 -- The stub was taken to be a new declaration. Indicate that
4143 Set_Has_Completion (Old_Id, False);
4149 Set_Has_Completion (Body_Id);
4150 Check_Eliminated (Body_Id);
4152 -- Analyze any aspect specifications that appear on the subprogram body
4153 -- stub. Stop the analysis now as the stub does not have a declarative
4154 -- or a statement part, and it cannot be inlined.
4156 if Nkind (N) = N_Subprogram_Body_Stub then
4157 if Has_Aspects (N) then
4158 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4166 -- Note: Normally we don't do any inlining if expansion is off, since
4167 -- we won't generate code in any case. An exception arises in GNATprove
4168 -- mode where we want to expand some calls in place, even with expansion
4169 -- disabled, since the inlining eases formal verification.
4171 if not GNATprove_Mode
4172 and then Expander_Active
4173 and then Serious_Errors_Detected = 0
4174 and then Present (Spec_Id)
4175 and then Has_Pragma_Inline (Spec_Id)
4177 -- Legacy implementation (relying on front-end inlining)
4179 if not Back_End_Inlining then
4180 if (Has_Pragma_Inline_Always (Spec_Id)
4181 and then not Opt.Disable_FE_Inline_Always)
4182 or else (Front_End_Inlining
4183 and then not Opt.Disable_FE_Inline)
4185 Build_Body_To_Inline (N, Spec_Id);
4188 -- New implementation (relying on back-end inlining)
4191 if Has_Pragma_Inline_Always (Spec_Id)
4192 or else Optimization_Level > 0
4194 -- Handle function returning an unconstrained type
4196 if Comes_From_Source (Body_Id)
4197 and then Ekind (Spec_Id) = E_Function
4198 and then Returns_Unconstrained_Type (Spec_Id)
4200 -- If function builds in place, i.e. returns a limited type,
4201 -- inlining cannot be done.
4203 and then not Is_Limited_Type (Etype (Spec_Id))
4205 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4209 Subp_Body : constant Node_Id :=
4210 Unit_Declaration_Node (Body_Id);
4211 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4214 -- Do not pass inlining to the backend if the subprogram
4215 -- has declarations or statements which cannot be inlined
4216 -- by the backend. This check is done here to emit an
4217 -- error instead of the generic warning message reported
4218 -- by the GCC backend (ie. "function might not be
4221 if Present (Subp_Decl)
4222 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4226 elsif Has_Excluded_Statement
4229 (Handled_Statement_Sequence (Subp_Body)))
4233 -- If the backend inlining is available then at this
4234 -- stage we only have to mark the subprogram as inlined.
4235 -- The expander will take care of registering it in the
4236 -- table of subprograms inlined by the backend a part of
4237 -- processing calls to it (cf. Expand_Call)
4240 Set_Is_Inlined (Spec_Id);
4247 -- In GNATprove mode, inline only when there is a separate subprogram
4248 -- declaration for now, as inlining of subprogram bodies acting as
4249 -- declarations, or subprogram stubs, are not supported by front-end
4250 -- inlining. This inlining should occur after analysis of the body, so
4251 -- that it is known whether the value of SPARK_Mode, which can be
4252 -- defined by a pragma inside the body, is applicable to the body.
4253 -- Inlining can be disabled with switch -gnatdm
4255 elsif GNATprove_Mode
4256 and then Full_Analysis
4257 and then not Inside_A_Generic
4258 and then Present (Spec_Id)
4260 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4261 and then Body_Has_SPARK_Mode_On
4262 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4263 and then not Body_Has_Contract
4264 and then not Debug_Flag_M
4266 Build_Body_To_Inline (N, Spec_Id);
4269 -- When generating code, inherited pre/postconditions are handled when
4270 -- expanding the corresponding contract.
4272 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4273 -- of the specification we have to install the private withed units.
4274 -- This holds for child units as well.
4276 if Is_Compilation_Unit (Body_Id)
4277 or else Nkind (Parent (N)) = N_Compilation_Unit
4279 Install_Private_With_Clauses (Body_Id);
4282 Check_Anonymous_Return;
4284 -- Set the Protected_Formal field of each extra formal of the protected
4285 -- subprogram to reference the corresponding extra formal of the
4286 -- subprogram that implements it. For regular formals this occurs when
4287 -- the protected subprogram's declaration is expanded, but the extra
4288 -- formals don't get created until the subprogram is frozen. We need to
4289 -- do this before analyzing the protected subprogram's body so that any
4290 -- references to the original subprogram's extra formals will be changed
4291 -- refer to the implementing subprogram's formals (see Expand_Formal).
4293 if Present (Spec_Id)
4294 and then Is_Protected_Type (Scope (Spec_Id))
4295 and then Present (Protected_Body_Subprogram (Spec_Id))
4298 Impl_Subp : constant Entity_Id :=
4299 Protected_Body_Subprogram (Spec_Id);
4300 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4301 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4304 while Present (Prot_Ext_Formal) loop
4305 pragma Assert (Present (Impl_Ext_Formal));
4306 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4307 Next_Formal_With_Extras (Prot_Ext_Formal);
4308 Next_Formal_With_Extras (Impl_Ext_Formal);
4313 -- Now we can go on to analyze the body
4315 HSS := Handled_Statement_Sequence (N);
4316 Set_Actual_Subtypes (N, Current_Scope);
4318 -- Add a declaration for the Protection object, renaming declarations
4319 -- for discriminals and privals and finally a declaration for the entry
4320 -- family index (if applicable). This form of early expansion is done
4321 -- when the Expander is active because Install_Private_Data_Declarations
4322 -- references entities which were created during regular expansion. The
4323 -- subprogram entity must come from source, and not be an internally
4324 -- generated subprogram.
4327 and then Present (Prot_Typ)
4328 and then Present (Spec_Id)
4329 and then Comes_From_Source (Spec_Id)
4330 and then not Is_Eliminated (Spec_Id)
4332 Install_Private_Data_Declarations
4333 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4336 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4337 -- may now appear in parameter and result profiles. Since the analysis
4338 -- of a subprogram body may use the parameter and result profile of the
4339 -- spec, swap any limited views with their non-limited counterpart.
4341 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4342 Exch_Views := Exchange_Limited_Views (Spec_Id);
4345 -- If the return type is an anonymous access type whose designated type
4346 -- is the limited view of a class-wide type and the non-limited view is
4347 -- available, update the return type accordingly.
4349 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4355 Rtyp := Etype (Spec_Id);
4357 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4358 Etyp := Directly_Designated_Type (Rtyp);
4360 if Is_Class_Wide_Type (Etyp)
4361 and then From_Limited_With (Etyp)
4364 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4370 -- Analyze any aspect specifications that appear on the subprogram body
4372 if Has_Aspects (N) then
4373 Analyze_Aspect_Specifications_On_Body_Or_Stub (N);
4376 Analyze_Declarations (Declarations (N));
4378 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4380 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4381 if Present (SPARK_Pragma (Spec_Id)) then
4382 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4384 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4386 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4387 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4388 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4390 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4393 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4397 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4398 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4399 Error_Msg_Sloc := Sloc (Spec_Id);
4401 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4405 -- A subprogram body freezes its own contract. Analyze the contract
4406 -- after the declarations of the body have been processed as pragmas
4407 -- are now chained on the contract of the subprogram body.
4409 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4411 -- Check completion, and analyze the statements
4414 Inspect_Deferred_Constant_Completion (Declarations (N));
4417 -- Deal with end of scope processing for the body
4419 Process_End_Label (HSS, 't', Current_Scope);
4420 Update_Use_Clause_Chain;
4423 -- If we are compiling an entry wrapper, remove the enclosing
4424 -- synchronized object from the stack.
4426 if Is_Entry_Wrapper (Body_Id) then
4430 Check_Subprogram_Order (N);
4431 Set_Analyzed (Body_Id);
4433 -- If we have a separate spec, then the analysis of the declarations
4434 -- caused the entities in the body to be chained to the spec id, but
4435 -- we want them chained to the body id. Only the formal parameters
4436 -- end up chained to the spec id in this case.
4438 if Present (Spec_Id) then
4440 -- We must conform to the categorization of our spec
4442 Validate_Categorization_Dependency (N, Spec_Id);
4444 -- And if this is a child unit, the parent units must conform
4446 if Is_Child_Unit (Spec_Id) then
4447 Validate_Categorization_Dependency
4448 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4451 -- Here is where we move entities from the spec to the body
4453 -- Case where there are entities that stay with the spec
4455 if Present (Last_Real_Spec_Entity) then
4457 -- No body entities (happens when the only real spec entities come
4458 -- from precondition and postcondition pragmas).
4460 if No (Last_Entity (Body_Id)) then
4461 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4463 -- Body entities present (formals), so chain stuff past them
4467 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4470 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4471 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4472 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4474 -- Case where there are no spec entities, in this case there can be
4475 -- no body entities either, so just move everything.
4477 -- If the body is generated for an expression function, it may have
4478 -- been preanalyzed already, if 'access was applied to it.
4481 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4482 N_Expression_Function
4484 pragma Assert (No (Last_Entity (Body_Id)));
4488 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4489 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4490 Set_First_Entity (Spec_Id, Empty);
4491 Set_Last_Entity (Spec_Id, Empty);
4494 -- Otherwise the body does not complete a previous declaration. Check
4495 -- the categorization of the body against the units it withs.
4498 Validate_Categorization_Dependency (N, Body_Id);
4501 Check_Missing_Return;
4503 -- Now we are going to check for variables that are never modified in
4504 -- the body of the procedure. But first we deal with a special case
4505 -- where we want to modify this check. If the body of the subprogram
4506 -- starts with a raise statement or its equivalent, or if the body
4507 -- consists entirely of a null statement, then it is pretty obvious that
4508 -- it is OK to not reference the parameters. For example, this might be
4509 -- the following common idiom for a stubbed function: statement of the
4510 -- procedure raises an exception. In particular this deals with the
4511 -- common idiom of a stubbed function, which appears something like:
4513 -- function F (A : Integer) return Some_Type;
4516 -- raise Program_Error;
4520 -- Here the purpose of X is simply to satisfy the annoying requirement
4521 -- in Ada that there be at least one return, and we certainly do not
4522 -- want to go posting warnings on X that it is not initialized. On
4523 -- the other hand, if X is entirely unreferenced that should still
4526 -- What we do is to detect these cases, and if we find them, flag the
4527 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4528 -- suppress unwanted warnings. For the case of the function stub above
4529 -- we have a special test to set X as apparently assigned to suppress
4536 -- Skip call markers installed by the ABE mechanism, labels, and
4537 -- Push_xxx_Error_Label to find the first real statement.
4539 Stm := First (Statements (HSS));
4540 while Nkind_In (Stm, N_Call_Marker, N_Label)
4541 or else Nkind (Stm) in N_Push_xxx_Label
4546 -- Do the test on the original statement before expansion
4549 Ostm : constant Node_Id := Original_Node (Stm);
4552 -- If explicit raise statement, turn on flag
4554 if Nkind (Ostm) = N_Raise_Statement then
4555 Set_Trivial_Subprogram (Stm);
4557 -- If null statement, and no following statements, turn on flag
4559 elsif Nkind (Stm) = N_Null_Statement
4560 and then Comes_From_Source (Stm)
4561 and then No (Next (Stm))
4563 Set_Trivial_Subprogram (Stm);
4565 -- Check for explicit call cases which likely raise an exception
4567 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4568 if Is_Entity_Name (Name (Ostm)) then
4570 Ent : constant Entity_Id := Entity (Name (Ostm));
4573 -- If the procedure is marked No_Return, then likely it
4574 -- raises an exception, but in any case it is not coming
4575 -- back here, so turn on the flag.
4578 and then Ekind (Ent) = E_Procedure
4579 and then No_Return (Ent)
4581 Set_Trivial_Subprogram (Stm);
4589 -- Check for variables that are never modified
4596 -- If there is a separate spec, then transfer Never_Set_In_Source
4597 -- flags from out parameters to the corresponding entities in the
4598 -- body. The reason we do that is we want to post error flags on
4599 -- the body entities, not the spec entities.
4601 if Present (Spec_Id) then
4602 E1 := First_Entity (Spec_Id);
4603 while Present (E1) loop
4604 if Ekind (E1) = E_Out_Parameter then
4605 E2 := First_Entity (Body_Id);
4606 while Present (E2) loop
4607 exit when Chars (E1) = Chars (E2);
4611 if Present (E2) then
4612 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4620 -- Check references in body
4622 Check_References (Body_Id);
4625 -- Check for nested subprogram, and mark outer level subprogram if so
4631 if Present (Spec_Id) then
4638 Ent := Enclosing_Subprogram (Ent);
4639 exit when No (Ent) or else Is_Subprogram (Ent);
4642 if Present (Ent) then
4643 Set_Has_Nested_Subprogram (Ent);
4647 -- Restore the limited views in the spec, if any, to let the back end
4648 -- process it without running into circularities.
4650 if Exch_Views /= No_Elist then
4651 Restore_Limited_Views (Exch_Views);
4654 if Mask_Types /= No_Elist then
4655 Unmask_Unfrozen_Types (Mask_Types);
4658 if Present (Desig_View) then
4659 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4663 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4664 Restore_Ghost_Mode (Saved_GM);
4665 end Analyze_Subprogram_Body_Helper;
4667 ------------------------------------
4668 -- Analyze_Subprogram_Declaration --
4669 ------------------------------------
4671 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4672 Scop : constant Entity_Id := Current_Scope;
4673 Designator : Entity_Id;
4675 Is_Completion : Boolean;
4676 -- Indicates whether a null procedure declaration is a completion
4679 -- Null procedures are not allowed in SPARK
4681 if Nkind (Specification (N)) = N_Procedure_Specification
4682 and then Null_Present (Specification (N))
4684 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4686 -- Null procedures are allowed in protected types, following the
4687 -- recent AI12-0147.
4689 if Is_Protected_Type (Current_Scope)
4690 and then Ada_Version < Ada_2012
4692 Error_Msg_N ("protected operation cannot be a null procedure", N);
4695 Analyze_Null_Procedure (N, Is_Completion);
4697 -- The null procedure acts as a body, nothing further is needed
4699 if Is_Completion then
4704 Designator := Analyze_Subprogram_Specification (Specification (N));
4706 -- A reference may already have been generated for the unit name, in
4707 -- which case the following call is redundant. However it is needed for
4708 -- declarations that are the rewriting of an expression function.
4710 Generate_Definition (Designator);
4712 -- Set the SPARK mode from the current context (may be overwritten later
4713 -- with explicit pragma). This is not done for entry barrier functions
4714 -- because they are generated outside the protected type and should not
4715 -- carry the mode of the enclosing context.
4717 if Nkind (N) = N_Subprogram_Declaration
4718 and then Is_Entry_Barrier_Function (N)
4723 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4724 Set_SPARK_Pragma_Inherited (Designator);
4727 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4728 -- the body of this subprogram is instantiated or inlined later and out
4729 -- of context. The body uses this attribute to restore the value of the
4732 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4733 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4736 -- Preserve relevant elaboration-related attributes of the context which
4737 -- are no longer available or very expensive to recompute once analysis,
4738 -- resolution, and expansion are over.
4740 Mark_Elaboration_Attributes
4741 (N_Id => Designator,
4744 if Debug_Flag_C then
4745 Write_Str ("==> subprogram spec ");
4746 Write_Name (Chars (Designator));
4747 Write_Str (" from ");
4748 Write_Location (Sloc (N));
4753 Validate_RCI_Subprogram_Declaration (N);
4754 New_Overloaded_Entity (Designator);
4755 Check_Delayed_Subprogram (Designator);
4757 -- If the type of the first formal of the current subprogram is a non-
4758 -- generic tagged private type, mark the subprogram as being a private
4759 -- primitive. Ditto if this is a function with controlling result, and
4760 -- the return type is currently private. In both cases, the type of the
4761 -- controlling argument or result must be in the current scope for the
4762 -- operation to be primitive.
4764 if Has_Controlling_Result (Designator)
4765 and then Is_Private_Type (Etype (Designator))
4766 and then Scope (Etype (Designator)) = Current_Scope
4767 and then not Is_Generic_Actual_Type (Etype (Designator))
4769 Set_Is_Private_Primitive (Designator);
4771 elsif Present (First_Formal (Designator)) then
4773 Formal_Typ : constant Entity_Id :=
4774 Etype (First_Formal (Designator));
4776 Set_Is_Private_Primitive (Designator,
4777 Is_Tagged_Type (Formal_Typ)
4778 and then Scope (Formal_Typ) = Current_Scope
4779 and then Is_Private_Type (Formal_Typ)
4780 and then not Is_Generic_Actual_Type (Formal_Typ));
4784 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4787 if Ada_Version >= Ada_2005
4788 and then Comes_From_Source (N)
4789 and then Is_Dispatching_Operation (Designator)
4796 if Has_Controlling_Result (Designator) then
4797 Etyp := Etype (Designator);
4800 E := First_Entity (Designator);
4802 and then Is_Formal (E)
4803 and then not Is_Controlling_Formal (E)
4811 if Is_Access_Type (Etyp) then
4812 Etyp := Directly_Designated_Type (Etyp);
4815 if Is_Interface (Etyp)
4816 and then not Is_Abstract_Subprogram (Designator)
4817 and then not (Ekind (Designator) = E_Procedure
4818 and then Null_Present (Specification (N)))
4820 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4822 -- Specialize error message based on procedures vs. functions,
4823 -- since functions can't be null subprograms.
4825 if Ekind (Designator) = E_Procedure then
4827 ("interface procedure % must be abstract or null", N);
4830 ("interface function % must be abstract", N);
4836 -- What is the following code for, it used to be
4838 -- ??? Set_Suppress_Elaboration_Checks
4839 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4841 -- The following seems equivalent, but a bit dubious
4843 if Elaboration_Checks_Suppressed (Designator) then
4844 Set_Kill_Elaboration_Checks (Designator);
4847 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4848 Set_Categorization_From_Scope (Designator, Scop);
4851 -- For a compilation unit, check for library-unit pragmas
4853 Push_Scope (Designator);
4854 Set_Categorization_From_Pragmas (N);
4855 Validate_Categorization_Dependency (N, Designator);
4859 -- For a compilation unit, set body required. This flag will only be
4860 -- reset if a valid Import or Interface pragma is processed later on.
4862 if Nkind (Parent (N)) = N_Compilation_Unit then
4863 Set_Body_Required (Parent (N), True);
4865 if Ada_Version >= Ada_2005
4866 and then Nkind (Specification (N)) = N_Procedure_Specification
4867 and then Null_Present (Specification (N))
4870 ("null procedure cannot be declared at library level", N);
4874 Generate_Reference_To_Formals (Designator);
4875 Check_Eliminated (Designator);
4877 if Debug_Flag_C then
4879 Write_Str ("<== subprogram spec ");
4880 Write_Name (Chars (Designator));
4881 Write_Str (" from ");
4882 Write_Location (Sloc (N));
4886 if Is_Protected_Type (Current_Scope) then
4888 -- Indicate that this is a protected operation, because it may be
4889 -- used in subsequent declarations within the protected type.
4891 Set_Convention (Designator, Convention_Protected);
4894 List_Inherited_Pre_Post_Aspects (Designator);
4896 if Has_Aspects (N) then
4897 Analyze_Aspect_Specifications (N, Designator);
4899 end Analyze_Subprogram_Declaration;
4901 --------------------------------------
4902 -- Analyze_Subprogram_Specification --
4903 --------------------------------------
4905 -- Reminder: N here really is a subprogram specification (not a subprogram
4906 -- declaration). This procedure is called to analyze the specification in
4907 -- both subprogram bodies and subprogram declarations (specs).
4909 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4910 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4911 -- Determine whether entity E denotes the spec or body of an invariant
4914 ------------------------------------
4915 -- Is_Invariant_Procedure_Or_Body --
4916 ------------------------------------
4918 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4919 Decl : constant Node_Id := Unit_Declaration_Node (E);
4923 if Nkind (Decl) = N_Subprogram_Body then
4924 Spec := Corresponding_Spec (Decl);
4931 and then Ekind (Spec) = E_Procedure
4932 and then (Is_Partial_Invariant_Procedure (Spec)
4933 or else Is_Invariant_Procedure (Spec));
4934 end Is_Invariant_Procedure_Or_Body;
4938 Designator : constant Entity_Id := Defining_Entity (N);
4939 Formals : constant List_Id := Parameter_Specifications (N);
4941 -- Start of processing for Analyze_Subprogram_Specification
4944 -- User-defined operator is not allowed in SPARK, except as a renaming
4946 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4947 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4949 Check_SPARK_05_Restriction
4950 ("user-defined operator is not allowed", N);
4953 -- Proceed with analysis. Do not emit a cross-reference entry if the
4954 -- specification comes from an expression function, because it may be
4955 -- the completion of a previous declaration. If it is not, the cross-
4956 -- reference entry will be emitted for the new subprogram declaration.
4958 if Nkind (Parent (N)) /= N_Expression_Function then
4959 Generate_Definition (Designator);
4962 if Nkind (N) = N_Function_Specification then
4963 Set_Ekind (Designator, E_Function);
4964 Set_Mechanism (Designator, Default_Mechanism);
4966 Set_Ekind (Designator, E_Procedure);
4967 Set_Etype (Designator, Standard_Void_Type);
4970 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4971 -- those subprograms which could be inlined in GNATprove mode (because
4972 -- Body_To_Inline is non-Empty) but should not be inlined.
4974 if GNATprove_Mode then
4975 Set_Is_Inlined_Always (Designator);
4978 -- Introduce new scope for analysis of the formals and the return type
4980 Set_Scope (Designator, Current_Scope);
4982 if Present (Formals) then
4983 Push_Scope (Designator);
4984 Process_Formals (Formals, N);
4986 -- Check dimensions in N for formals with default expression
4988 Analyze_Dimension_Formals (N, Formals);
4990 -- Ada 2005 (AI-345): If this is an overriding operation of an
4991 -- inherited interface operation, and the controlling type is
4992 -- a synchronized type, replace the type with its corresponding
4993 -- record, to match the proper signature of an overriding operation.
4994 -- Same processing for an access parameter whose designated type is
4995 -- derived from a synchronized interface.
4997 -- This modification is not done for invariant procedures because
4998 -- the corresponding record may not necessarely be visible when the
4999 -- concurrent type acts as the full view of a private type.
5002 -- type Prot is private with Type_Invariant => ...;
5003 -- procedure ConcInvariant (Obj : Prot);
5005 -- protected type Prot is ...;
5006 -- type Concurrent_Record_Prot is record ...;
5007 -- procedure ConcInvariant (Obj : Prot) is
5009 -- end ConcInvariant;
5012 -- In the example above, both the spec and body of the invariant
5013 -- procedure must utilize the private type as the controlling type.
5015 if Ada_Version >= Ada_2005
5016 and then not Is_Invariant_Procedure_Or_Body (Designator)
5020 Formal_Typ : Entity_Id;
5021 Rec_Typ : Entity_Id;
5022 Desig_Typ : Entity_Id;
5025 Formal := First_Formal (Designator);
5026 while Present (Formal) loop
5027 Formal_Typ := Etype (Formal);
5029 if Is_Concurrent_Type (Formal_Typ)
5030 and then Present (Corresponding_Record_Type (Formal_Typ))
5032 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5034 if Present (Interfaces (Rec_Typ)) then
5035 Set_Etype (Formal, Rec_Typ);
5038 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5039 Desig_Typ := Designated_Type (Formal_Typ);
5041 if Is_Concurrent_Type (Desig_Typ)
5042 and then Present (Corresponding_Record_Type (Desig_Typ))
5044 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5046 if Present (Interfaces (Rec_Typ)) then
5047 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5052 Next_Formal (Formal);
5059 -- The subprogram scope is pushed and popped around the processing of
5060 -- the return type for consistency with call above to Process_Formals
5061 -- (which itself can call Analyze_Return_Type), and to ensure that any
5062 -- itype created for the return type will be associated with the proper
5065 elsif Nkind (N) = N_Function_Specification then
5066 Push_Scope (Designator);
5067 Analyze_Return_Type (N);
5073 if Nkind (N) = N_Function_Specification then
5075 -- Deal with operator symbol case
5077 if Nkind (Designator) = N_Defining_Operator_Symbol then
5078 Valid_Operator_Definition (Designator);
5081 May_Need_Actuals (Designator);
5083 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5084 -- the subprogram is abstract also. This does not apply to renaming
5085 -- declarations, where abstractness is inherited, and to subprogram
5086 -- bodies generated for stream operations, which become renamings as
5089 -- In case of primitives associated with abstract interface types
5090 -- the check is applied later (see Analyze_Subprogram_Declaration).
5092 if not Nkind_In (Original_Node (Parent (N)),
5093 N_Abstract_Subprogram_Declaration,
5094 N_Formal_Abstract_Subprogram_Declaration,
5095 N_Subprogram_Renaming_Declaration)
5097 if Is_Abstract_Type (Etype (Designator))
5098 and then not Is_Interface (Etype (Designator))
5101 ("function that returns abstract type must be abstract", N);
5103 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5104 -- access result whose designated type is abstract.
5106 elsif Ada_Version >= Ada_2012
5107 and then Nkind (Result_Definition (N)) = N_Access_Definition
5109 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5110 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5113 ("function whose access result designates abstract type "
5114 & "must be abstract", N);
5120 end Analyze_Subprogram_Specification;
5122 -----------------------
5123 -- Check_Conformance --
5124 -----------------------
5126 procedure Check_Conformance
5127 (New_Id : Entity_Id;
5129 Ctype : Conformance_Type;
5131 Conforms : out Boolean;
5132 Err_Loc : Node_Id := Empty;
5133 Get_Inst : Boolean := False;
5134 Skip_Controlling_Formals : Boolean := False)
5136 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5137 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5138 -- If Errmsg is True, then processing continues to post an error message
5139 -- for conformance error on given node. Two messages are output. The
5140 -- first message points to the previous declaration with a general "no
5141 -- conformance" message. The second is the detailed reason, supplied as
5142 -- Msg. The parameter N provide information for a possible & insertion
5143 -- in the message, and also provides the location for posting the
5144 -- message in the absence of a specified Err_Loc location.
5146 function Conventions_Match
5148 Id2 : Entity_Id) return Boolean;
5149 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5152 -----------------------
5153 -- Conformance_Error --
5154 -----------------------
5156 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5163 if No (Err_Loc) then
5169 Error_Msg_Sloc := Sloc (Old_Id);
5172 when Type_Conformant =>
5173 Error_Msg_N -- CODEFIX
5174 ("not type conformant with declaration#!", Enode);
5176 when Mode_Conformant =>
5177 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5179 ("not mode conformant with operation inherited#!",
5183 ("not mode conformant with declaration#!", Enode);
5186 when Subtype_Conformant =>
5187 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5189 ("not subtype conformant with operation inherited#!",
5193 ("not subtype conformant with declaration#!", Enode);
5196 when Fully_Conformant =>
5197 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5198 Error_Msg_N -- CODEFIX
5199 ("not fully conformant with operation inherited#!",
5202 Error_Msg_N -- CODEFIX
5203 ("not fully conformant with declaration#!", Enode);
5207 Error_Msg_NE (Msg, Enode, N);
5209 end Conformance_Error;
5211 -----------------------
5212 -- Conventions_Match --
5213 -----------------------
5215 function Conventions_Match
5217 Id2 : Entity_Id) return Boolean
5220 -- Ignore the conventions of anonymous access-to-subprogram types
5221 -- and subprogram types because these are internally generated and
5222 -- the only way these may receive a convention is if they inherit
5223 -- the convention of a related subprogram.
5225 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5228 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5233 -- Otherwise compare the conventions directly
5236 return Convention (Id1) = Convention (Id2);
5238 end Conventions_Match;
5242 Old_Type : constant Entity_Id := Etype (Old_Id);
5243 New_Type : constant Entity_Id := Etype (New_Id);
5244 Old_Formal : Entity_Id;
5245 New_Formal : Entity_Id;
5246 Access_Types_Match : Boolean;
5247 Old_Formal_Base : Entity_Id;
5248 New_Formal_Base : Entity_Id;
5250 -- Start of processing for Check_Conformance
5255 -- We need a special case for operators, since they don't appear
5258 if Ctype = Type_Conformant then
5259 if Ekind (New_Id) = E_Operator
5260 and then Operator_Matches_Spec (New_Id, Old_Id)
5266 -- If both are functions/operators, check return types conform
5268 if Old_Type /= Standard_Void_Type
5270 New_Type /= Standard_Void_Type
5272 -- If we are checking interface conformance we omit controlling
5273 -- arguments and result, because we are only checking the conformance
5274 -- of the remaining parameters.
5276 if Has_Controlling_Result (Old_Id)
5277 and then Has_Controlling_Result (New_Id)
5278 and then Skip_Controlling_Formals
5282 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5283 if Ctype >= Subtype_Conformant
5284 and then not Predicates_Match (Old_Type, New_Type)
5287 ("\predicate of return type does not match!", New_Id);
5290 ("\return type does not match!", New_Id);
5296 -- Ada 2005 (AI-231): In case of anonymous access types check the
5297 -- null-exclusion and access-to-constant attributes match.
5299 if Ada_Version >= Ada_2005
5300 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5302 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5303 or else Is_Access_Constant (Etype (Old_Type)) /=
5304 Is_Access_Constant (Etype (New_Type)))
5306 Conformance_Error ("\return type does not match!", New_Id);
5310 -- If either is a function/operator and the other isn't, error
5312 elsif Old_Type /= Standard_Void_Type
5313 or else New_Type /= Standard_Void_Type
5315 Conformance_Error ("\functions can only match functions!", New_Id);
5319 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5320 -- If this is a renaming as body, refine error message to indicate that
5321 -- the conflict is with the original declaration. If the entity is not
5322 -- frozen, the conventions don't have to match, the one of the renamed
5323 -- entity is inherited.
5325 if Ctype >= Subtype_Conformant then
5326 if not Conventions_Match (Old_Id, New_Id) then
5327 if not Is_Frozen (New_Id) then
5330 elsif Present (Err_Loc)
5331 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5332 and then Present (Corresponding_Spec (Err_Loc))
5334 Error_Msg_Name_1 := Chars (New_Id);
5336 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5337 Conformance_Error ("\prior declaration for% has convention %!");
5340 Conformance_Error ("\calling conventions do not match!");
5345 elsif Is_Formal_Subprogram (Old_Id)
5346 or else Is_Formal_Subprogram (New_Id)
5348 Conformance_Error ("\formal subprograms not allowed!");
5353 -- Deal with parameters
5355 -- Note: we use the entity information, rather than going directly
5356 -- to the specification in the tree. This is not only simpler, but
5357 -- absolutely necessary for some cases of conformance tests between
5358 -- operators, where the declaration tree simply does not exist.
5360 Old_Formal := First_Formal (Old_Id);
5361 New_Formal := First_Formal (New_Id);
5362 while Present (Old_Formal) and then Present (New_Formal) loop
5363 if Is_Controlling_Formal (Old_Formal)
5364 and then Is_Controlling_Formal (New_Formal)
5365 and then Skip_Controlling_Formals
5367 -- The controlling formals will have different types when
5368 -- comparing an interface operation with its match, but both
5369 -- or neither must be access parameters.
5371 if Is_Access_Type (Etype (Old_Formal))
5373 Is_Access_Type (Etype (New_Formal))
5375 goto Skip_Controlling_Formal;
5378 ("\access parameter does not match!", New_Formal);
5382 -- Ada 2012: Mode conformance also requires that formal parameters
5383 -- be both aliased, or neither.
5385 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5386 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5388 ("\aliased parameter mismatch!", New_Formal);
5392 if Ctype = Fully_Conformant then
5394 -- Names must match. Error message is more accurate if we do
5395 -- this before checking that the types of the formals match.
5397 if Chars (Old_Formal) /= Chars (New_Formal) then
5398 Conformance_Error ("\name& does not match!", New_Formal);
5400 -- Set error posted flag on new formal as well to stop
5401 -- junk cascaded messages in some cases.
5403 Set_Error_Posted (New_Formal);
5407 -- Null exclusion must match
5409 if Null_Exclusion_Present (Parent (Old_Formal))
5411 Null_Exclusion_Present (Parent (New_Formal))
5413 -- Only give error if both come from source. This should be
5414 -- investigated some time, since it should not be needed ???
5416 if Comes_From_Source (Old_Formal)
5418 Comes_From_Source (New_Formal)
5421 ("\null exclusion for& does not match", New_Formal);
5423 -- Mark error posted on the new formal to avoid duplicated
5424 -- complaint about types not matching.
5426 Set_Error_Posted (New_Formal);
5431 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5432 -- case occurs whenever a subprogram is being renamed and one of its
5433 -- parameters imposes a null exclusion. For example:
5435 -- type T is null record;
5436 -- type Acc_T is access T;
5437 -- subtype Acc_T_Sub is Acc_T;
5439 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5440 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5443 Old_Formal_Base := Etype (Old_Formal);
5444 New_Formal_Base := Etype (New_Formal);
5447 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5448 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5451 Access_Types_Match := Ada_Version >= Ada_2005
5453 -- Ensure that this rule is only applied when New_Id is a
5454 -- renaming of Old_Id.
5456 and then Nkind (Parent (Parent (New_Id))) =
5457 N_Subprogram_Renaming_Declaration
5458 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5459 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5460 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5462 -- Now handle the allowed access-type case
5464 and then Is_Access_Type (Old_Formal_Base)
5465 and then Is_Access_Type (New_Formal_Base)
5467 -- The type kinds must match. The only exception occurs with
5468 -- multiple generics of the form:
5471 -- type F is private; type A is private;
5472 -- type F_Ptr is access F; type A_Ptr is access A;
5473 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5474 -- package F_Pack is ... package A_Pack is
5475 -- package F_Inst is
5476 -- new F_Pack (A, A_Ptr, A_P);
5478 -- When checking for conformance between the parameters of A_P
5479 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5480 -- because the compiler has transformed A_Ptr into a subtype of
5481 -- F_Ptr. We catch this case in the code below.
5483 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5485 (Is_Generic_Type (Old_Formal_Base)
5486 and then Is_Generic_Type (New_Formal_Base)
5487 and then Is_Internal (New_Formal_Base)
5488 and then Etype (Etype (New_Formal_Base)) =
5490 and then Directly_Designated_Type (Old_Formal_Base) =
5491 Directly_Designated_Type (New_Formal_Base)
5492 and then ((Is_Itype (Old_Formal_Base)
5493 and then Can_Never_Be_Null (Old_Formal_Base))
5495 (Is_Itype (New_Formal_Base)
5496 and then Can_Never_Be_Null (New_Formal_Base)));
5498 -- Types must always match. In the visible part of an instance,
5499 -- usual overloading rules for dispatching operations apply, and
5500 -- we check base types (not the actual subtypes).
5502 if In_Instance_Visible_Part
5503 and then Is_Dispatching_Operation (New_Id)
5505 if not Conforming_Types
5506 (T1 => Base_Type (Etype (Old_Formal)),
5507 T2 => Base_Type (Etype (New_Formal)),
5509 Get_Inst => Get_Inst)
5510 and then not Access_Types_Match
5512 Conformance_Error ("\type of & does not match!", New_Formal);
5516 elsif not Conforming_Types
5517 (T1 => Old_Formal_Base,
5518 T2 => New_Formal_Base,
5520 Get_Inst => Get_Inst)
5521 and then not Access_Types_Match
5523 -- Don't give error message if old type is Any_Type. This test
5524 -- avoids some cascaded errors, e.g. in case of a bad spec.
5526 if Errmsg and then Old_Formal_Base = Any_Type then
5529 if Ctype >= Subtype_Conformant
5531 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5534 ("\predicate of & does not match!", New_Formal);
5537 ("\type of & does not match!", New_Formal);
5539 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5541 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5549 -- For mode conformance, mode must match
5551 if Ctype >= Mode_Conformant then
5552 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5553 if not Ekind_In (New_Id, E_Function, E_Procedure)
5554 or else not Is_Primitive_Wrapper (New_Id)
5556 Conformance_Error ("\mode of & does not match!", New_Formal);
5560 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5562 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5564 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5567 ("\mode of & does not match!", New_Formal);
5574 -- Part of mode conformance for access types is having the same
5575 -- constant modifier.
5577 elsif Access_Types_Match
5578 and then Is_Access_Constant (Old_Formal_Base) /=
5579 Is_Access_Constant (New_Formal_Base)
5582 ("\constant modifier does not match!", New_Formal);
5587 if Ctype >= Subtype_Conformant then
5589 -- Ada 2005 (AI-231): In case of anonymous access types check
5590 -- the null-exclusion and access-to-constant attributes must
5591 -- match. For null exclusion, we test the types rather than the
5592 -- formals themselves, since the attribute is only set reliably
5593 -- on the formals in the Ada 95 case, and we exclude the case
5594 -- where Old_Formal is marked as controlling, to avoid errors
5595 -- when matching completing bodies with dispatching declarations
5596 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5598 if Ada_Version >= Ada_2005
5599 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5600 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5602 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5603 Can_Never_Be_Null (Etype (New_Formal))
5605 not Is_Controlling_Formal (Old_Formal))
5607 Is_Access_Constant (Etype (Old_Formal)) /=
5608 Is_Access_Constant (Etype (New_Formal)))
5610 -- Do not complain if error already posted on New_Formal. This
5611 -- avoids some redundant error messages.
5613 and then not Error_Posted (New_Formal)
5615 -- It is allowed to omit the null-exclusion in case of stream
5616 -- attribute subprograms. We recognize stream subprograms
5617 -- through their TSS-generated suffix.
5620 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5623 if TSS_Name /= TSS_Stream_Read
5624 and then TSS_Name /= TSS_Stream_Write
5625 and then TSS_Name /= TSS_Stream_Input
5626 and then TSS_Name /= TSS_Stream_Output
5628 -- Here we have a definite conformance error. It is worth
5629 -- special casing the error message for the case of a
5630 -- controlling formal (which excludes null).
5632 if Is_Controlling_Formal (New_Formal) then
5633 Error_Msg_Node_2 := Scope (New_Formal);
5635 ("\controlling formal & of & excludes null, "
5636 & "declaration must exclude null as well",
5639 -- Normal case (couldn't we give more detail here???)
5643 ("\type of & does not match!", New_Formal);
5652 -- Full conformance checks
5654 if Ctype = Fully_Conformant then
5656 -- We have checked already that names match
5658 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5660 -- Check default expressions for in parameters
5663 NewD : constant Boolean :=
5664 Present (Default_Value (New_Formal));
5665 OldD : constant Boolean :=
5666 Present (Default_Value (Old_Formal));
5668 if NewD or OldD then
5670 -- The old default value has been analyzed because the
5671 -- current full declaration will have frozen everything
5672 -- before. The new default value has not been analyzed,
5673 -- so analyze it now before we check for conformance.
5676 Push_Scope (New_Id);
5677 Preanalyze_Spec_Expression
5678 (Default_Value (New_Formal), Etype (New_Formal));
5682 if not (NewD and OldD)
5683 or else not Fully_Conformant_Expressions
5684 (Default_Value (Old_Formal),
5685 Default_Value (New_Formal))
5688 ("\default expression for & does not match!",
5697 -- A couple of special checks for Ada 83 mode. These checks are
5698 -- skipped if either entity is an operator in package Standard,
5699 -- or if either old or new instance is not from the source program.
5701 if Ada_Version = Ada_83
5702 and then Sloc (Old_Id) > Standard_Location
5703 and then Sloc (New_Id) > Standard_Location
5704 and then Comes_From_Source (Old_Id)
5705 and then Comes_From_Source (New_Id)
5708 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5709 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5712 -- Explicit IN must be present or absent in both cases. This
5713 -- test is required only in the full conformance case.
5715 if In_Present (Old_Param) /= In_Present (New_Param)
5716 and then Ctype = Fully_Conformant
5719 ("\(Ada 83) IN must appear in both declarations",
5724 -- Grouping (use of comma in param lists) must be the same
5725 -- This is where we catch a misconformance like:
5728 -- A : Integer; B : Integer
5730 -- which are represented identically in the tree except
5731 -- for the setting of the flags More_Ids and Prev_Ids.
5733 if More_Ids (Old_Param) /= More_Ids (New_Param)
5734 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5737 ("\grouping of & does not match!", New_Formal);
5743 -- This label is required when skipping controlling formals
5745 <<Skip_Controlling_Formal>>
5747 Next_Formal (Old_Formal);
5748 Next_Formal (New_Formal);
5751 if Present (Old_Formal) then
5752 Conformance_Error ("\too few parameters!");
5755 elsif Present (New_Formal) then
5756 Conformance_Error ("\too many parameters!", New_Formal);
5759 end Check_Conformance;
5761 -----------------------
5762 -- Check_Conventions --
5763 -----------------------
5765 procedure Check_Conventions (Typ : Entity_Id) is
5766 Ifaces_List : Elist_Id;
5768 procedure Check_Convention (Op : Entity_Id);
5769 -- Verify that the convention of inherited dispatching operation Op is
5770 -- consistent among all subprograms it overrides. In order to minimize
5771 -- the search, Search_From is utilized to designate a specific point in
5772 -- the list rather than iterating over the whole list once more.
5774 ----------------------
5775 -- Check_Convention --
5776 ----------------------
5778 procedure Check_Convention (Op : Entity_Id) is
5779 Op_Conv : constant Convention_Id := Convention (Op);
5780 Iface_Conv : Convention_Id;
5781 Iface_Elmt : Elmt_Id;
5782 Iface_Prim_Elmt : Elmt_Id;
5783 Iface_Prim : Entity_Id;
5786 Iface_Elmt := First_Elmt (Ifaces_List);
5787 while Present (Iface_Elmt) loop
5789 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5790 while Present (Iface_Prim_Elmt) loop
5791 Iface_Prim := Node (Iface_Prim_Elmt);
5792 Iface_Conv := Convention (Iface_Prim);
5794 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5795 and then Iface_Conv /= Op_Conv
5798 ("inconsistent conventions in primitive operations", Typ);
5800 Error_Msg_Name_1 := Chars (Op);
5801 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5802 Error_Msg_Sloc := Sloc (Op);
5804 if Comes_From_Source (Op) or else No (Alias (Op)) then
5805 if not Present (Overridden_Operation (Op)) then
5806 Error_Msg_N ("\\primitive % defined #", Typ);
5809 ("\\overriding operation % with "
5810 & "convention % defined #", Typ);
5813 else pragma Assert (Present (Alias (Op)));
5814 Error_Msg_Sloc := Sloc (Alias (Op));
5815 Error_Msg_N ("\\inherited operation % with "
5816 & "convention % defined #", Typ);
5819 Error_Msg_Name_1 := Chars (Op);
5820 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5821 Error_Msg_Sloc := Sloc (Iface_Prim);
5822 Error_Msg_N ("\\overridden operation % with "
5823 & "convention % defined #", Typ);
5825 -- Avoid cascading errors
5830 Next_Elmt (Iface_Prim_Elmt);
5833 Next_Elmt (Iface_Elmt);
5835 end Check_Convention;
5839 Prim_Op : Entity_Id;
5840 Prim_Op_Elmt : Elmt_Id;
5842 -- Start of processing for Check_Conventions
5845 if not Has_Interfaces (Typ) then
5849 Collect_Interfaces (Typ, Ifaces_List);
5851 -- The algorithm checks every overriding dispatching operation against
5852 -- all the corresponding overridden dispatching operations, detecting
5853 -- differences in conventions.
5855 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5856 while Present (Prim_Op_Elmt) loop
5857 Prim_Op := Node (Prim_Op_Elmt);
5859 -- A small optimization: skip the predefined dispatching operations
5860 -- since they always have the same convention.
5862 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5863 Check_Convention (Prim_Op);
5866 Next_Elmt (Prim_Op_Elmt);
5868 end Check_Conventions;
5870 ------------------------------
5871 -- Check_Delayed_Subprogram --
5872 ------------------------------
5874 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5875 procedure Possible_Freeze (T : Entity_Id);
5876 -- T is the type of either a formal parameter or of the return type. If
5877 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5878 -- itself must be delayed.
5880 ---------------------
5881 -- Possible_Freeze --
5882 ---------------------
5884 procedure Possible_Freeze (T : Entity_Id) is
5885 Scop : constant Entity_Id := Scope (Designator);
5888 -- If the subprogram appears within a package instance (which may be
5889 -- the wrapper package of a subprogram instance) the freeze node for
5890 -- that package will freeze the subprogram at the proper place, so
5891 -- do not emit a freeze node for the subprogram, given that it may
5892 -- appear in the wrong scope.
5894 if Ekind (Scop) = E_Package
5895 and then not Comes_From_Source (Scop)
5896 and then Is_Generic_Instance (Scop)
5900 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5901 Set_Has_Delayed_Freeze (Designator);
5903 elsif Is_Access_Type (T)
5904 and then Has_Delayed_Freeze (Designated_Type (T))
5905 and then not Is_Frozen (Designated_Type (T))
5907 Set_Has_Delayed_Freeze (Designator);
5909 end Possible_Freeze;
5915 -- Start of processing for Check_Delayed_Subprogram
5918 -- All subprograms, including abstract subprograms, may need a freeze
5919 -- node if some formal type or the return type needs one.
5921 Possible_Freeze (Etype (Designator));
5922 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5924 -- Need delayed freeze if any of the formal types themselves need a
5925 -- delayed freeze and are not yet frozen.
5927 F := First_Formal (Designator);
5928 while Present (F) loop
5929 Possible_Freeze (Etype (F));
5930 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5934 -- Mark functions that return by reference. Note that it cannot be done
5935 -- for delayed_freeze subprograms because the underlying returned type
5936 -- may not be known yet (for private types).
5938 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5940 Typ : constant Entity_Id := Etype (Designator);
5941 Utyp : constant Entity_Id := Underlying_Type (Typ);
5944 if Is_Limited_View (Typ) then
5945 Set_Returns_By_Ref (Designator);
5947 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5948 Set_Returns_By_Ref (Designator);
5952 end Check_Delayed_Subprogram;
5954 ------------------------------------
5955 -- Check_Discriminant_Conformance --
5956 ------------------------------------
5958 procedure Check_Discriminant_Conformance
5963 Old_Discr : Entity_Id := First_Discriminant (Prev);
5964 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5965 New_Discr_Id : Entity_Id;
5966 New_Discr_Type : Entity_Id;
5968 procedure Conformance_Error (Msg : String; N : Node_Id);
5969 -- Post error message for conformance error on given node. Two messages
5970 -- are output. The first points to the previous declaration with a
5971 -- general "no conformance" message. The second is the detailed reason,
5972 -- supplied as Msg. The parameter N provide information for a possible
5973 -- & insertion in the message.
5975 -----------------------
5976 -- Conformance_Error --
5977 -----------------------
5979 procedure Conformance_Error (Msg : String; N : Node_Id) is
5981 Error_Msg_Sloc := Sloc (Prev_Loc);
5982 Error_Msg_N -- CODEFIX
5983 ("not fully conformant with declaration#!", N);
5984 Error_Msg_NE (Msg, N, N);
5985 end Conformance_Error;
5987 -- Start of processing for Check_Discriminant_Conformance
5990 while Present (Old_Discr) and then Present (New_Discr) loop
5991 New_Discr_Id := Defining_Identifier (New_Discr);
5993 -- The subtype mark of the discriminant on the full type has not
5994 -- been analyzed so we do it here. For an access discriminant a new
5997 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
5999 Access_Definition (N, Discriminant_Type (New_Discr));
6002 Analyze (Discriminant_Type (New_Discr));
6003 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6005 -- Ada 2005: if the discriminant definition carries a null
6006 -- exclusion, create an itype to check properly for consistency
6007 -- with partial declaration.
6009 if Is_Access_Type (New_Discr_Type)
6010 and then Null_Exclusion_Present (New_Discr)
6013 Create_Null_Excluding_Itype
6014 (T => New_Discr_Type,
6015 Related_Nod => New_Discr,
6016 Scope_Id => Current_Scope);
6020 if not Conforming_Types
6021 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6023 Conformance_Error ("type of & does not match!", New_Discr_Id);
6026 -- Treat the new discriminant as an occurrence of the old one,
6027 -- for navigation purposes, and fill in some semantic
6028 -- information, for completeness.
6030 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6031 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6032 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6037 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6038 Conformance_Error ("name & does not match!", New_Discr_Id);
6042 -- Default expressions must match
6045 NewD : constant Boolean :=
6046 Present (Expression (New_Discr));
6047 OldD : constant Boolean :=
6048 Present (Expression (Parent (Old_Discr)));
6051 if NewD or OldD then
6053 -- The old default value has been analyzed and expanded,
6054 -- because the current full declaration will have frozen
6055 -- everything before. The new default values have not been
6056 -- expanded, so expand now to check conformance.
6059 Preanalyze_Spec_Expression
6060 (Expression (New_Discr), New_Discr_Type);
6063 if not (NewD and OldD)
6064 or else not Fully_Conformant_Expressions
6065 (Expression (Parent (Old_Discr)),
6066 Expression (New_Discr))
6070 ("default expression for & does not match!",
6077 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6079 if Ada_Version = Ada_83 then
6081 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6084 -- Grouping (use of comma in param lists) must be the same
6085 -- This is where we catch a misconformance like:
6088 -- A : Integer; B : Integer
6090 -- which are represented identically in the tree except
6091 -- for the setting of the flags More_Ids and Prev_Ids.
6093 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6094 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6097 ("grouping of & does not match!", New_Discr_Id);
6103 Next_Discriminant (Old_Discr);
6107 if Present (Old_Discr) then
6108 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6111 elsif Present (New_Discr) then
6113 ("too many discriminants!", Defining_Identifier (New_Discr));
6116 end Check_Discriminant_Conformance;
6118 ----------------------------
6119 -- Check_Fully_Conformant --
6120 ----------------------------
6122 procedure Check_Fully_Conformant
6123 (New_Id : Entity_Id;
6125 Err_Loc : Node_Id := Empty)
6128 pragma Warnings (Off, Result);
6131 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6132 end Check_Fully_Conformant;
6134 --------------------------
6135 -- Check_Limited_Return --
6136 --------------------------
6138 procedure Check_Limited_Return
6144 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6145 -- replaced by anonymous access results. This is an incompatibility with
6146 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6147 -- controllable with special switch. ???
6149 -- A limited interface that is not immutably limited is OK
6151 if Is_Limited_Interface (R_Type)
6153 not (Is_Task_Interface (R_Type)
6154 or else Is_Protected_Interface (R_Type)
6155 or else Is_Synchronized_Interface (R_Type))
6159 elsif Is_Limited_Type (R_Type)
6160 and then not Is_Interface (R_Type)
6161 and then Comes_From_Source (N)
6162 and then not In_Instance_Body
6163 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6165 -- Error in Ada 2005
6167 if Ada_Version >= Ada_2005
6168 and then not Debug_Flag_Dot_L
6169 and then not GNAT_Mode
6172 ("(Ada 2005) cannot copy object of a limited type "
6173 & "(RM-2005 6.5(5.5/2))", Expr);
6175 if Is_Limited_View (R_Type) then
6177 ("\return by reference not permitted in Ada 2005", Expr);
6180 -- Warn in Ada 95 mode, to give folks a heads up about this
6183 -- In GNAT mode, this is just a warning, to allow it to be evilly
6184 -- turned off. Otherwise it is a real error.
6186 -- In a generic context, simplify the warning because it makes no
6187 -- sense to discuss pass-by-reference or copy.
6189 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6190 if Inside_A_Generic then
6192 ("return of limited object not permitted in Ada 2005 "
6193 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6195 elsif Is_Limited_View (R_Type) then
6197 ("return by reference not permitted in Ada 2005 "
6198 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6201 ("cannot copy object of a limited type in Ada 2005 "
6202 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6205 -- Ada 95 mode, and compatibility warnings disabled
6208 pragma Assert (Ada_Version <= Ada_95);
6209 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6210 return; -- skip continuation messages below
6213 if not Inside_A_Generic then
6215 ("\consider switching to return of access type", Expr);
6216 Explain_Limited_Type (R_Type, Expr);
6219 end Check_Limited_Return;
6221 ---------------------------
6222 -- Check_Mode_Conformant --
6223 ---------------------------
6225 procedure Check_Mode_Conformant
6226 (New_Id : Entity_Id;
6228 Err_Loc : Node_Id := Empty;
6229 Get_Inst : Boolean := False)
6232 pragma Warnings (Off, Result);
6235 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6236 end Check_Mode_Conformant;
6238 --------------------------------
6239 -- Check_Overriding_Indicator --
6240 --------------------------------
6242 procedure Check_Overriding_Indicator
6244 Overridden_Subp : Entity_Id;
6245 Is_Primitive : Boolean)
6251 -- No overriding indicator for literals
6253 if Ekind (Subp) = E_Enumeration_Literal then
6256 elsif Ekind (Subp) = E_Entry then
6257 Decl := Parent (Subp);
6259 -- No point in analyzing a malformed operator
6261 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6262 and then Error_Posted (Subp)
6267 Decl := Unit_Declaration_Node (Subp);
6270 if Nkind_In (Decl, N_Subprogram_Body,
6271 N_Subprogram_Body_Stub,
6272 N_Subprogram_Declaration,
6273 N_Abstract_Subprogram_Declaration,
6274 N_Subprogram_Renaming_Declaration)
6276 Spec := Specification (Decl);
6278 elsif Nkind (Decl) = N_Entry_Declaration then
6285 -- The overriding operation is type conformant with the overridden one,
6286 -- but the names of the formals are not required to match. If the names
6287 -- appear permuted in the overriding operation, this is a possible
6288 -- source of confusion that is worth diagnosing. Controlling formals
6289 -- often carry names that reflect the type, and it is not worthwhile
6290 -- requiring that their names match.
6292 if Present (Overridden_Subp)
6293 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6300 Form1 := First_Formal (Subp);
6301 Form2 := First_Formal (Overridden_Subp);
6303 -- If the overriding operation is a synchronized operation, skip
6304 -- the first parameter of the overridden operation, which is
6305 -- implicit in the new one. If the operation is declared in the
6306 -- body it is not primitive and all formals must match.
6308 if Is_Concurrent_Type (Scope (Subp))
6309 and then Is_Tagged_Type (Scope (Subp))
6310 and then not Has_Completion (Scope (Subp))
6312 Form2 := Next_Formal (Form2);
6315 if Present (Form1) then
6316 Form1 := Next_Formal (Form1);
6317 Form2 := Next_Formal (Form2);
6320 while Present (Form1) loop
6321 if not Is_Controlling_Formal (Form1)
6322 and then Present (Next_Formal (Form2))
6323 and then Chars (Form1) = Chars (Next_Formal (Form2))
6325 Error_Msg_Node_2 := Alias (Overridden_Subp);
6326 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6328 ("& does not match corresponding formal of&#",
6333 Next_Formal (Form1);
6334 Next_Formal (Form2);
6339 -- If there is an overridden subprogram, then check that there is no
6340 -- "not overriding" indicator, and mark the subprogram as overriding.
6341 -- This is not done if the overridden subprogram is marked as hidden,
6342 -- which can occur for the case of inherited controlled operations
6343 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6344 -- subprogram is not itself hidden. (Note: This condition could probably
6345 -- be simplified, leaving out the testing for the specific controlled
6346 -- cases, but it seems safer and clearer this way, and echoes similar
6347 -- special-case tests of this kind in other places.)
6349 if Present (Overridden_Subp)
6350 and then (not Is_Hidden (Overridden_Subp)
6352 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6355 and then Present (Alias (Overridden_Subp))
6356 and then not Is_Hidden (Alias (Overridden_Subp))))
6358 if Must_Not_Override (Spec) then
6359 Error_Msg_Sloc := Sloc (Overridden_Subp);
6361 if Ekind (Subp) = E_Entry then
6363 ("entry & overrides inherited operation #", Spec, Subp);
6366 ("subprogram & overrides inherited operation #", Spec, Subp);
6369 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6370 -- as an extension of Root_Controlled, and thus has a useless Adjust
6371 -- operation. This operation should not be inherited by other limited
6372 -- controlled types. An explicit Adjust for them is not overriding.
6374 elsif Must_Override (Spec)
6375 and then Chars (Overridden_Subp) = Name_Adjust
6376 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6377 and then Present (Alias (Overridden_Subp))
6378 and then In_Predefined_Unit (Alias (Overridden_Subp))
6381 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6382 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6384 elsif Is_Subprogram (Subp) then
6385 if Is_Init_Proc (Subp) then
6388 elsif No (Overridden_Operation (Subp)) then
6390 -- For entities generated by Derive_Subprograms the overridden
6391 -- operation is the inherited primitive (which is available
6392 -- through the attribute alias)
6394 if (Is_Dispatching_Operation (Subp)
6395 or else Is_Dispatching_Operation (Overridden_Subp))
6396 and then not Comes_From_Source (Overridden_Subp)
6397 and then Find_Dispatching_Type (Overridden_Subp) =
6398 Find_Dispatching_Type (Subp)
6399 and then Present (Alias (Overridden_Subp))
6400 and then Comes_From_Source (Alias (Overridden_Subp))
6402 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6403 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6406 Set_Overridden_Operation (Subp, Overridden_Subp);
6407 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6412 -- If primitive flag is set or this is a protected operation, then
6413 -- the operation is overriding at the point of its declaration, so
6414 -- warn if necessary. Otherwise it may have been declared before the
6415 -- operation it overrides and no check is required.
6418 and then not Must_Override (Spec)
6419 and then (Is_Primitive
6420 or else Ekind (Scope (Subp)) = E_Protected_Type)
6422 Style.Missing_Overriding (Decl, Subp);
6425 -- If Subp is an operator, it may override a predefined operation, if
6426 -- it is defined in the same scope as the type to which it applies.
6427 -- In that case Overridden_Subp is empty because of our implicit
6428 -- representation for predefined operators. We have to check whether the
6429 -- signature of Subp matches that of a predefined operator. Note that
6430 -- first argument provides the name of the operator, and the second
6431 -- argument the signature that may match that of a standard operation.
6432 -- If the indicator is overriding, then the operator must match a
6433 -- predefined signature, because we know already that there is no
6434 -- explicit overridden operation.
6436 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6437 if Must_Not_Override (Spec) then
6439 -- If this is not a primitive or a protected subprogram, then
6440 -- "not overriding" is illegal.
6443 and then Ekind (Scope (Subp)) /= E_Protected_Type
6445 Error_Msg_N ("overriding indicator only allowed "
6446 & "if subprogram is primitive", Subp);
6448 elsif Can_Override_Operator (Subp) then
6450 ("subprogram& overrides predefined operator ", Spec, Subp);
6453 elsif Must_Override (Spec) then
6454 if No (Overridden_Operation (Subp))
6455 and then not Can_Override_Operator (Subp)
6457 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6460 elsif not Error_Posted (Subp)
6461 and then Style_Check
6462 and then Can_Override_Operator (Subp)
6463 and then not In_Predefined_Unit (Subp)
6465 -- If style checks are enabled, indicate that the indicator is
6466 -- missing. However, at the point of declaration, the type of
6467 -- which this is a primitive operation may be private, in which
6468 -- case the indicator would be premature.
6470 if Has_Private_Declaration (Etype (Subp))
6471 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6475 Style.Missing_Overriding (Decl, Subp);
6479 elsif Must_Override (Spec) then
6480 if Ekind (Subp) = E_Entry then
6481 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6483 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6486 -- If the operation is marked "not overriding" and it's not primitive
6487 -- then an error is issued, unless this is an operation of a task or
6488 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6489 -- has been specified have already been checked above.
6491 elsif Must_Not_Override (Spec)
6492 and then not Is_Primitive
6493 and then Ekind (Subp) /= E_Entry
6494 and then Ekind (Scope (Subp)) /= E_Protected_Type
6497 ("overriding indicator only allowed if subprogram is primitive",
6501 end Check_Overriding_Indicator;
6507 -- Note: this procedure needs to know far too much about how the expander
6508 -- messes with exceptions. The use of the flag Exception_Junk and the
6509 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6510 -- works, but is not very clean. It would be better if the expansion
6511 -- routines would leave Original_Node working nicely, and we could use
6512 -- Original_Node here to ignore all the peculiar expander messing ???
6514 procedure Check_Returns
6518 Proc : Entity_Id := Empty)
6522 procedure Check_Statement_Sequence (L : List_Id);
6523 -- Internal recursive procedure to check a list of statements for proper
6524 -- termination by a return statement (or a transfer of control or a
6525 -- compound statement that is itself internally properly terminated).
6527 ------------------------------
6528 -- Check_Statement_Sequence --
6529 ------------------------------
6531 procedure Check_Statement_Sequence (L : List_Id) is
6536 function Assert_False return Boolean;
6537 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6538 -- rewritten as a null statement when assertions are off. The assert
6539 -- is not active, but it is still enough to kill the warning.
6545 function Assert_False return Boolean is
6546 Orig : constant Node_Id := Original_Node (Last_Stm);
6549 if Nkind (Orig) = N_Pragma
6550 and then Pragma_Name (Orig) = Name_Assert
6551 and then not Error_Posted (Orig)
6554 Arg : constant Node_Id :=
6555 First (Pragma_Argument_Associations (Orig));
6556 Exp : constant Node_Id := Expression (Arg);
6558 return Nkind (Exp) = N_Identifier
6559 and then Chars (Exp) = Name_False;
6569 Raise_Exception_Call : Boolean;
6570 -- Set True if statement sequence terminated by Raise_Exception call
6571 -- or a Reraise_Occurrence call.
6573 -- Start of processing for Check_Statement_Sequence
6576 Raise_Exception_Call := False;
6578 -- Get last real statement
6580 Last_Stm := Last (L);
6582 -- Deal with digging out exception handler statement sequences that
6583 -- have been transformed by the local raise to goto optimization.
6584 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6585 -- optimization has occurred, we are looking at something like:
6588 -- original stmts in block
6592 -- goto L1; | omitted if No_Exception_Propagation
6597 -- goto L3; -- skip handler when exception not raised
6599 -- <<L1>> -- target label for local exception
6613 -- and what we have to do is to dig out the estmts1 and estmts2
6614 -- sequences (which were the original sequences of statements in
6615 -- the exception handlers) and check them.
6617 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6622 exit when Nkind (Stm) /= N_Block_Statement;
6623 exit when not Exception_Junk (Stm);
6626 exit when Nkind (Stm) /= N_Label;
6627 exit when not Exception_Junk (Stm);
6628 Check_Statement_Sequence
6629 (Statements (Handled_Statement_Sequence (Next (Stm))));
6634 exit when Nkind (Stm) /= N_Goto_Statement;
6635 exit when not Exception_Junk (Stm);
6639 -- Don't count pragmas
6641 while Nkind (Last_Stm) = N_Pragma
6643 -- Don't count call to SS_Release (can happen after Raise_Exception)
6646 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6648 Nkind (Name (Last_Stm)) = N_Identifier
6650 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6652 -- Don't count exception junk
6655 (Nkind_In (Last_Stm, N_Goto_Statement,
6657 N_Object_Declaration)
6658 and then Exception_Junk (Last_Stm))
6659 or else Nkind (Last_Stm) in N_Push_xxx_Label
6660 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6662 -- Inserted code, such as finalization calls, is irrelevant: we only
6663 -- need to check original source.
6665 or else Is_Rewrite_Insertion (Last_Stm)
6670 -- Here we have the "real" last statement
6672 Kind := Nkind (Last_Stm);
6674 -- Transfer of control, OK. Note that in the No_Return procedure
6675 -- case, we already diagnosed any explicit return statements, so
6676 -- we can treat them as OK in this context.
6678 if Is_Transfer (Last_Stm) then
6681 -- Check cases of explicit non-indirect procedure calls
6683 elsif Kind = N_Procedure_Call_Statement
6684 and then Is_Entity_Name (Name (Last_Stm))
6686 -- Check call to Raise_Exception procedure which is treated
6687 -- specially, as is a call to Reraise_Occurrence.
6689 -- We suppress the warning in these cases since it is likely that
6690 -- the programmer really does not expect to deal with the case
6691 -- of Null_Occurrence, and thus would find a warning about a
6692 -- missing return curious, and raising Program_Error does not
6693 -- seem such a bad behavior if this does occur.
6695 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6696 -- behavior will be to raise Constraint_Error (see AI-329).
6698 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6700 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6702 Raise_Exception_Call := True;
6704 -- For Raise_Exception call, test first argument, if it is
6705 -- an attribute reference for a 'Identity call, then we know
6706 -- that the call cannot possibly return.
6709 Arg : constant Node_Id :=
6710 Original_Node (First_Actual (Last_Stm));
6712 if Nkind (Arg) = N_Attribute_Reference
6713 and then Attribute_Name (Arg) = Name_Identity
6720 -- If statement, need to look inside if there is an else and check
6721 -- each constituent statement sequence for proper termination.
6723 elsif Kind = N_If_Statement
6724 and then Present (Else_Statements (Last_Stm))
6726 Check_Statement_Sequence (Then_Statements (Last_Stm));
6727 Check_Statement_Sequence (Else_Statements (Last_Stm));
6729 if Present (Elsif_Parts (Last_Stm)) then
6731 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6734 while Present (Elsif_Part) loop
6735 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6743 -- Case statement, check each case for proper termination
6745 elsif Kind = N_Case_Statement then
6749 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6750 while Present (Case_Alt) loop
6751 Check_Statement_Sequence (Statements (Case_Alt));
6752 Next_Non_Pragma (Case_Alt);
6758 -- Block statement, check its handled sequence of statements
6760 elsif Kind = N_Block_Statement then
6766 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6775 -- Loop statement. If there is an iteration scheme, we can definitely
6776 -- fall out of the loop. Similarly if there is an exit statement, we
6777 -- can fall out. In either case we need a following return.
6779 elsif Kind = N_Loop_Statement then
6780 if Present (Iteration_Scheme (Last_Stm))
6781 or else Has_Exit (Entity (Identifier (Last_Stm)))
6785 -- A loop with no exit statement or iteration scheme is either
6786 -- an infinite loop, or it has some other exit (raise/return).
6787 -- In either case, no warning is required.
6793 -- Timed entry call, check entry call and delay alternatives
6795 -- Note: in expanded code, the timed entry call has been converted
6796 -- to a set of expanded statements on which the check will work
6797 -- correctly in any case.
6799 elsif Kind = N_Timed_Entry_Call then
6801 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6802 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6805 -- If statement sequence of entry call alternative is missing,
6806 -- then we can definitely fall through, and we post the error
6807 -- message on the entry call alternative itself.
6809 if No (Statements (ECA)) then
6812 -- If statement sequence of delay alternative is missing, then
6813 -- we can definitely fall through, and we post the error
6814 -- message on the delay alternative itself.
6816 -- Note: if both ECA and DCA are missing the return, then we
6817 -- post only one message, should be enough to fix the bugs.
6818 -- If not we will get a message next time on the DCA when the
6821 elsif No (Statements (DCA)) then
6824 -- Else check both statement sequences
6827 Check_Statement_Sequence (Statements (ECA));
6828 Check_Statement_Sequence (Statements (DCA));
6833 -- Conditional entry call, check entry call and else part
6835 -- Note: in expanded code, the conditional entry call has been
6836 -- converted to a set of expanded statements on which the check
6837 -- will work correctly in any case.
6839 elsif Kind = N_Conditional_Entry_Call then
6841 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6844 -- If statement sequence of entry call alternative is missing,
6845 -- then we can definitely fall through, and we post the error
6846 -- message on the entry call alternative itself.
6848 if No (Statements (ECA)) then
6851 -- Else check statement sequence and else part
6854 Check_Statement_Sequence (Statements (ECA));
6855 Check_Statement_Sequence (Else_Statements (Last_Stm));
6861 -- If we fall through, issue appropriate message
6865 -- Kill warning if last statement is a raise exception call,
6866 -- or a pragma Assert (False). Note that with assertions enabled,
6867 -- such a pragma has been converted into a raise exception call
6868 -- already, so the Assert_False is for the assertions off case.
6870 if not Raise_Exception_Call and then not Assert_False then
6872 -- In GNATprove mode, it is an error to have a missing return
6874 Error_Msg_Warn := SPARK_Mode /= On;
6876 -- Issue error message or warning
6879 ("RETURN statement missing following this statement<<!",
6882 ("\Program_Error ]<<!", Last_Stm);
6885 -- Note: we set Err even though we have not issued a warning
6886 -- because we still have a case of a missing return. This is
6887 -- an extremely marginal case, probably will never be noticed
6888 -- but we might as well get it right.
6892 -- Otherwise we have the case of a procedure marked No_Return
6895 if not Raise_Exception_Call then
6896 if GNATprove_Mode then
6898 ("implied return after this statement would have raised "
6899 & "Program_Error", Last_Stm);
6901 -- In normal compilation mode, do not warn on a generated call
6902 -- (e.g. in the body of a renaming as completion).
6904 elsif Comes_From_Source (Last_Stm) then
6906 ("implied return after this statement will raise "
6907 & "Program_Error??", Last_Stm);
6910 Error_Msg_Warn := SPARK_Mode /= On;
6912 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6916 RE : constant Node_Id :=
6917 Make_Raise_Program_Error (Sloc (Last_Stm),
6918 Reason => PE_Implicit_Return);
6920 Insert_After (Last_Stm, RE);
6924 end Check_Statement_Sequence;
6926 -- Start of processing for Check_Returns
6930 Check_Statement_Sequence (Statements (HSS));
6932 if Present (Exception_Handlers (HSS)) then
6933 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6934 while Present (Handler) loop
6935 Check_Statement_Sequence (Statements (Handler));
6936 Next_Non_Pragma (Handler);
6941 ----------------------------
6942 -- Check_Subprogram_Order --
6943 ----------------------------
6945 procedure Check_Subprogram_Order (N : Node_Id) is
6947 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6948 -- This is used to check if S1 > S2 in the sense required by this test,
6949 -- for example nameab < namec, but name2 < name10.
6951 -----------------------------
6952 -- Subprogram_Name_Greater --
6953 -----------------------------
6955 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6960 -- Deal with special case where names are identical except for a
6961 -- numerical suffix. These are handled specially, taking the numeric
6962 -- ordering from the suffix into account.
6965 while S1 (L1) in '0' .. '9' loop
6970 while S2 (L2) in '0' .. '9' loop
6974 -- If non-numeric parts non-equal, do straight compare
6976 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6979 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6980 -- that a missing suffix is treated as numeric zero in this test.
6984 while L1 < S1'Last loop
6986 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6990 while L2 < S2'Last loop
6992 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
6997 end Subprogram_Name_Greater;
6999 -- Start of processing for Check_Subprogram_Order
7002 -- Check body in alpha order if this is option
7005 and then Style_Check_Order_Subprograms
7006 and then Nkind (N) = N_Subprogram_Body
7007 and then Comes_From_Source (N)
7008 and then In_Extended_Main_Source_Unit (N)
7012 renames Scope_Stack.Table
7013 (Scope_Stack.Last).Last_Subprogram_Name;
7015 Body_Id : constant Entity_Id :=
7016 Defining_Entity (Specification (N));
7019 Get_Decoded_Name_String (Chars (Body_Id));
7022 if Subprogram_Name_Greater
7023 (LSN.all, Name_Buffer (1 .. Name_Len))
7025 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7031 LSN := new String'(Name_Buffer (1 .. Name_Len));
7034 end Check_Subprogram_Order;
7036 ------------------------------
7037 -- Check_Subtype_Conformant --
7038 ------------------------------
7040 procedure Check_Subtype_Conformant
7041 (New_Id : Entity_Id;
7043 Err_Loc : Node_Id := Empty;
7044 Skip_Controlling_Formals : Boolean := False;
7045 Get_Inst : Boolean := False)
7048 pragma Warnings (Off, Result);
7051 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7052 Skip_Controlling_Formals => Skip_Controlling_Formals,
7053 Get_Inst => Get_Inst);
7054 end Check_Subtype_Conformant;
7056 -----------------------------------
7057 -- Check_Synchronized_Overriding --
7058 -----------------------------------
7060 procedure Check_Synchronized_Overriding
7061 (Def_Id : Entity_Id;
7062 Overridden_Subp : out Entity_Id)
7064 Ifaces_List : Elist_Id;
7068 function Matches_Prefixed_View_Profile
7069 (Prim_Params : List_Id;
7070 Iface_Params : List_Id) return Boolean;
7071 -- Determine whether a subprogram's parameter profile Prim_Params
7072 -- matches that of a potentially overridden interface subprogram
7073 -- Iface_Params. Also determine if the type of first parameter of
7074 -- Iface_Params is an implemented interface.
7076 -----------------------------------
7077 -- Matches_Prefixed_View_Profile --
7078 -----------------------------------
7080 function Matches_Prefixed_View_Profile
7081 (Prim_Params : List_Id;
7082 Iface_Params : List_Id) return Boolean
7084 function Is_Implemented
7085 (Ifaces_List : Elist_Id;
7086 Iface : Entity_Id) return Boolean;
7087 -- Determine if Iface is implemented by the current task or
7090 --------------------
7091 -- Is_Implemented --
7092 --------------------
7094 function Is_Implemented
7095 (Ifaces_List : Elist_Id;
7096 Iface : Entity_Id) return Boolean
7098 Iface_Elmt : Elmt_Id;
7101 Iface_Elmt := First_Elmt (Ifaces_List);
7102 while Present (Iface_Elmt) loop
7103 if Node (Iface_Elmt) = Iface then
7107 Next_Elmt (Iface_Elmt);
7115 Iface_Id : Entity_Id;
7116 Iface_Param : Node_Id;
7117 Iface_Typ : Entity_Id;
7118 Prim_Id : Entity_Id;
7119 Prim_Param : Node_Id;
7120 Prim_Typ : Entity_Id;
7122 -- Start of processing for Matches_Prefixed_View_Profile
7125 Iface_Param := First (Iface_Params);
7126 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7128 if Is_Access_Type (Iface_Typ) then
7129 Iface_Typ := Designated_Type (Iface_Typ);
7132 Prim_Param := First (Prim_Params);
7134 -- The first parameter of the potentially overridden subprogram must
7135 -- be an interface implemented by Prim.
7137 if not Is_Interface (Iface_Typ)
7138 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7143 -- The checks on the object parameters are done, so move on to the
7144 -- rest of the parameters.
7146 if not In_Scope then
7147 Prim_Param := Next (Prim_Param);
7150 Iface_Param := Next (Iface_Param);
7151 while Present (Iface_Param) and then Present (Prim_Param) loop
7152 Iface_Id := Defining_Identifier (Iface_Param);
7153 Iface_Typ := Find_Parameter_Type (Iface_Param);
7155 Prim_Id := Defining_Identifier (Prim_Param);
7156 Prim_Typ := Find_Parameter_Type (Prim_Param);
7158 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7159 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7160 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7162 Iface_Typ := Designated_Type (Iface_Typ);
7163 Prim_Typ := Designated_Type (Prim_Typ);
7166 -- Case of multiple interface types inside a parameter profile
7168 -- (Obj_Param : in out Iface; ...; Param : Iface)
7170 -- If the interface type is implemented, then the matching type in
7171 -- the primitive should be the implementing record type.
7173 if Ekind (Iface_Typ) = E_Record_Type
7174 and then Is_Interface (Iface_Typ)
7175 and then Is_Implemented (Ifaces_List, Iface_Typ)
7177 if Prim_Typ /= Typ then
7181 -- The two parameters must be both mode and subtype conformant
7183 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7185 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7194 -- One of the two lists contains more parameters than the other
7196 if Present (Iface_Param) or else Present (Prim_Param) then
7201 end Matches_Prefixed_View_Profile;
7203 -- Start of processing for Check_Synchronized_Overriding
7206 Overridden_Subp := Empty;
7208 -- Def_Id must be an entry or a subprogram. We should skip predefined
7209 -- primitives internally generated by the front end; however at this
7210 -- stage predefined primitives are still not fully decorated. As a
7211 -- minor optimization we skip here internally generated subprograms.
7213 if (Ekind (Def_Id) /= E_Entry
7214 and then Ekind (Def_Id) /= E_Function
7215 and then Ekind (Def_Id) /= E_Procedure)
7216 or else not Comes_From_Source (Def_Id)
7221 -- Search for the concurrent declaration since it contains the list of
7222 -- all implemented interfaces. In this case, the subprogram is declared
7223 -- within the scope of a protected or a task type.
7225 if Present (Scope (Def_Id))
7226 and then Is_Concurrent_Type (Scope (Def_Id))
7227 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7229 Typ := Scope (Def_Id);
7232 -- The enclosing scope is not a synchronized type and the subprogram
7235 elsif No (First_Formal (Def_Id)) then
7238 -- The subprogram has formals and hence it may be a primitive of a
7242 Typ := Etype (First_Formal (Def_Id));
7244 if Is_Access_Type (Typ) then
7245 Typ := Directly_Designated_Type (Typ);
7248 if Is_Concurrent_Type (Typ)
7249 and then not Is_Generic_Actual_Type (Typ)
7253 -- This case occurs when the concurrent type is declared within a
7254 -- generic unit. As a result the corresponding record has been built
7255 -- and used as the type of the first formal, we just have to retrieve
7256 -- the corresponding concurrent type.
7258 elsif Is_Concurrent_Record_Type (Typ)
7259 and then not Is_Class_Wide_Type (Typ)
7260 and then Present (Corresponding_Concurrent_Type (Typ))
7262 Typ := Corresponding_Concurrent_Type (Typ);
7270 -- There is no overriding to check if this is an inherited operation in
7271 -- a type derivation for a generic actual.
7273 Collect_Interfaces (Typ, Ifaces_List);
7275 if Is_Empty_Elmt_List (Ifaces_List) then
7279 -- Determine whether entry or subprogram Def_Id overrides a primitive
7280 -- operation that belongs to one of the interfaces in Ifaces_List.
7283 Candidate : Entity_Id := Empty;
7284 Hom : Entity_Id := Empty;
7285 Subp : Entity_Id := Empty;
7288 -- Traverse the homonym chain, looking for a potentially overridden
7289 -- subprogram that belongs to an implemented interface.
7291 Hom := Current_Entity_In_Scope (Def_Id);
7292 while Present (Hom) loop
7296 or else not Is_Overloadable (Subp)
7297 or else not Is_Primitive (Subp)
7298 or else not Is_Dispatching_Operation (Subp)
7299 or else not Present (Find_Dispatching_Type (Subp))
7300 or else not Is_Interface (Find_Dispatching_Type (Subp))
7304 -- Entries and procedures can override abstract or null interface
7307 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7308 and then Ekind (Subp) = E_Procedure
7309 and then Matches_Prefixed_View_Profile
7310 (Parameter_Specifications (Parent (Def_Id)),
7311 Parameter_Specifications (Parent (Subp)))
7315 -- For an overridden subprogram Subp, check whether the mode
7316 -- of its first parameter is correct depending on the kind of
7317 -- synchronized type.
7320 Formal : constant Node_Id := First_Formal (Candidate);
7323 -- In order for an entry or a protected procedure to
7324 -- override, the first parameter of the overridden routine
7325 -- must be of mode "out", "in out", or access-to-variable.
7327 if Ekind_In (Candidate, E_Entry, E_Procedure)
7328 and then Is_Protected_Type (Typ)
7329 and then Ekind (Formal) /= E_In_Out_Parameter
7330 and then Ekind (Formal) /= E_Out_Parameter
7331 and then Nkind (Parameter_Type (Parent (Formal))) /=
7336 -- All other cases are OK since a task entry or routine does
7337 -- not have a restriction on the mode of the first parameter
7338 -- of the overridden interface routine.
7341 Overridden_Subp := Candidate;
7346 -- Functions can override abstract interface functions
7348 elsif Ekind (Def_Id) = E_Function
7349 and then Ekind (Subp) = E_Function
7350 and then Matches_Prefixed_View_Profile
7351 (Parameter_Specifications (Parent (Def_Id)),
7352 Parameter_Specifications (Parent (Subp)))
7353 and then Etype (Def_Id) = Etype (Subp)
7357 -- If an inherited subprogram is implemented by a protected
7358 -- function, then the first parameter of the inherited
7359 -- subprogram shall be of mode in, but not an access-to-
7360 -- variable parameter (RM 9.4(11/9)).
7362 if Present (First_Formal (Subp))
7363 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7365 (not Is_Access_Type (Etype (First_Formal (Subp)))
7367 Is_Access_Constant (Etype (First_Formal (Subp))))
7369 Overridden_Subp := Subp;
7374 Hom := Homonym (Hom);
7377 -- After examining all candidates for overriding, we are left with
7378 -- the best match, which is a mode-incompatible interface routine.
7380 if In_Scope and then Present (Candidate) then
7381 Error_Msg_PT (Def_Id, Candidate);
7384 Overridden_Subp := Candidate;
7387 end Check_Synchronized_Overriding;
7389 ---------------------------
7390 -- Check_Type_Conformant --
7391 ---------------------------
7393 procedure Check_Type_Conformant
7394 (New_Id : Entity_Id;
7396 Err_Loc : Node_Id := Empty)
7399 pragma Warnings (Off, Result);
7402 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7403 end Check_Type_Conformant;
7405 ---------------------------
7406 -- Can_Override_Operator --
7407 ---------------------------
7409 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7413 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7417 Typ := Base_Type (Etype (First_Formal (Subp)));
7419 -- Check explicitly that the operation is a primitive of the type
7421 return Operator_Matches_Spec (Subp, Subp)
7422 and then not Is_Generic_Type (Typ)
7423 and then Scope (Subp) = Scope (Typ)
7424 and then not Is_Class_Wide_Type (Typ);
7426 end Can_Override_Operator;
7428 ----------------------
7429 -- Conforming_Types --
7430 ----------------------
7432 function Conforming_Types
7435 Ctype : Conformance_Type;
7436 Get_Inst : Boolean := False) return Boolean
7438 function Base_Types_Match
7440 Typ_2 : Entity_Id) return Boolean;
7441 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7442 -- in different scopes (e.g. parent and child instances), then verify
7443 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7444 -- the same subtype chain. The whole purpose of this procedure is to
7445 -- prevent spurious ambiguities in an instantiation that may arise if
7446 -- two distinct generic types are instantiated with the same actual.
7448 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7449 -- An access parameter can designate an incomplete type. If the
7450 -- incomplete type is the limited view of a type from a limited_
7451 -- with_clause, check whether the non-limited view is available.
7452 -- If it is a (non-limited) incomplete type, get the full view.
7454 function Matches_Limited_With_View
7456 Typ_2 : Entity_Id) return Boolean;
7457 -- Returns True if and only if either Typ_1 denotes a limited view of
7458 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7459 -- the limited with view of a type is used in a subprogram declaration
7460 -- and the subprogram body is in the scope of a regular with clause for
7461 -- the same unit. In such a case, the two type entities are considered
7462 -- identical for purposes of conformance checking.
7464 ----------------------
7465 -- Base_Types_Match --
7466 ----------------------
7468 function Base_Types_Match
7470 Typ_2 : Entity_Id) return Boolean
7472 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7473 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7476 if Typ_1 = Typ_2 then
7479 elsif Base_1 = Base_2 then
7481 -- The following is too permissive. A more precise test should
7482 -- check that the generic actual is an ancestor subtype of the
7485 -- See code in Find_Corresponding_Spec that applies an additional
7486 -- filter to handle accidental amiguities in instances.
7489 not Is_Generic_Actual_Type (Typ_1)
7490 or else not Is_Generic_Actual_Type (Typ_2)
7491 or else Scope (Typ_1) /= Scope (Typ_2);
7493 -- If Typ_2 is a generic actual type it is declared as the subtype of
7494 -- the actual. If that actual is itself a subtype we need to use its
7495 -- own base type to check for compatibility.
7497 elsif Ekind (Base_2) = Ekind (Typ_2)
7498 and then Base_1 = Base_Type (Base_2)
7502 elsif Ekind (Base_1) = Ekind (Typ_1)
7503 and then Base_2 = Base_Type (Base_1)
7510 end Base_Types_Match;
7512 --------------------------
7513 -- Find_Designated_Type --
7514 --------------------------
7516 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7520 Desig := Directly_Designated_Type (Typ);
7522 if Ekind (Desig) = E_Incomplete_Type then
7524 -- If regular incomplete type, get full view if available
7526 if Present (Full_View (Desig)) then
7527 Desig := Full_View (Desig);
7529 -- If limited view of a type, get non-limited view if available,
7530 -- and check again for a regular incomplete type.
7532 elsif Present (Non_Limited_View (Desig)) then
7533 Desig := Get_Full_View (Non_Limited_View (Desig));
7538 end Find_Designated_Type;
7540 -------------------------------
7541 -- Matches_Limited_With_View --
7542 -------------------------------
7544 function Matches_Limited_With_View
7546 Typ_2 : Entity_Id) return Boolean
7548 function Is_Matching_Limited_View
7550 View : Entity_Id) return Boolean;
7551 -- Determine whether non-limited view View denotes type Typ in some
7552 -- conformant fashion.
7554 ------------------------------
7555 -- Is_Matching_Limited_View --
7556 ------------------------------
7558 function Is_Matching_Limited_View
7560 View : Entity_Id) return Boolean
7562 Root_Typ : Entity_Id;
7563 Root_View : Entity_Id;
7566 -- The non-limited view directly denotes the type
7571 -- The type is a subtype of the non-limited view
7573 elsif Is_Subtype_Of (Typ, View) then
7576 -- Both the non-limited view and the type denote class-wide types
7578 elsif Is_Class_Wide_Type (Typ)
7579 and then Is_Class_Wide_Type (View)
7581 Root_Typ := Root_Type (Typ);
7582 Root_View := Root_Type (View);
7584 if Root_Typ = Root_View then
7587 -- An incomplete tagged type and its full view may receive two
7588 -- distinct class-wide types when the related package has not
7589 -- been analyzed yet.
7592 -- type T is tagged; -- CW_1
7593 -- type T is tagged null record; -- CW_2
7596 -- This is because the package lacks any semantic information
7597 -- that may eventually link both views of T. As a consequence,
7598 -- a client of the limited view of Pack will see CW_2 while a
7599 -- client of the non-limited view of Pack will see CW_1.
7601 elsif Is_Incomplete_Type (Root_Typ)
7602 and then Present (Full_View (Root_Typ))
7603 and then Full_View (Root_Typ) = Root_View
7607 elsif Is_Incomplete_Type (Root_View)
7608 and then Present (Full_View (Root_View))
7609 and then Full_View (Root_View) = Root_Typ
7616 end Is_Matching_Limited_View;
7618 -- Start of processing for Matches_Limited_With_View
7621 -- In some cases a type imported through a limited_with clause, and
7622 -- its non-limited view are both visible, for example in an anonymous
7623 -- access-to-class-wide type in a formal, or when building the body
7624 -- for a subprogram renaming after the subprogram has been frozen.
7625 -- In these cases both entities designate the same type. In addition,
7626 -- if one of them is an actual in an instance, it may be a subtype of
7627 -- the non-limited view of the other.
7629 if From_Limited_With (Typ_1)
7630 and then From_Limited_With (Typ_2)
7631 and then Available_View (Typ_1) = Available_View (Typ_2)
7635 elsif From_Limited_With (Typ_1) then
7636 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7638 elsif From_Limited_With (Typ_2) then
7639 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7644 end Matches_Limited_With_View;
7648 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7650 Type_1 : Entity_Id := T1;
7651 Type_2 : Entity_Id := T2;
7653 -- Start of processing for Conforming_Types
7656 -- The context is an instance association for a formal access-to-
7657 -- subprogram type; the formal parameter types require mapping because
7658 -- they may denote other formal parameters of the generic unit.
7661 Type_1 := Get_Instance_Of (T1);
7662 Type_2 := Get_Instance_Of (T2);
7665 -- If one of the types is a view of the other introduced by a limited
7666 -- with clause, treat these as conforming for all purposes.
7668 if Matches_Limited_With_View (T1, T2) then
7671 elsif Base_Types_Match (Type_1, Type_2) then
7672 if Ctype <= Mode_Conformant then
7677 Subtypes_Statically_Match (Type_1, Type_2)
7678 and then Dimensions_Match (Type_1, Type_2);
7681 elsif Is_Incomplete_Or_Private_Type (Type_1)
7682 and then Present (Full_View (Type_1))
7683 and then Base_Types_Match (Full_View (Type_1), Type_2)
7686 Ctype <= Mode_Conformant
7687 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7689 elsif Ekind (Type_2) = E_Incomplete_Type
7690 and then Present (Full_View (Type_2))
7691 and then Base_Types_Match (Type_1, Full_View (Type_2))
7694 Ctype <= Mode_Conformant
7695 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7697 elsif Is_Private_Type (Type_2)
7698 and then In_Instance
7699 and then Present (Full_View (Type_2))
7700 and then Base_Types_Match (Type_1, Full_View (Type_2))
7703 Ctype <= Mode_Conformant
7704 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7706 -- Another confusion between views in a nested instance with an
7707 -- actual private type whose full view is not in scope.
7709 elsif Ekind (Type_2) = E_Private_Subtype
7710 and then In_Instance
7711 and then Etype (Type_2) = Type_1
7715 -- In Ada 2012, incomplete types (including limited views) can appear
7716 -- as actuals in instantiations, where they are conformant to the
7717 -- corresponding incomplete formal.
7719 elsif Is_Incomplete_Type (Type_1)
7720 and then Is_Incomplete_Type (Type_2)
7721 and then In_Instance
7722 and then (Used_As_Generic_Actual (Type_1)
7723 or else Used_As_Generic_Actual (Type_2))
7728 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7729 -- treated recursively because they carry a signature. As far as
7730 -- conformance is concerned, convention plays no role, and either
7731 -- or both could be access to protected subprograms.
7733 Are_Anonymous_Access_To_Subprogram_Types :=
7734 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7735 E_Anonymous_Access_Protected_Subprogram_Type)
7737 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7738 E_Anonymous_Access_Protected_Subprogram_Type);
7740 -- Test anonymous access type case. For this case, static subtype
7741 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7742 -- the base types because we may have built internal subtype entities
7743 -- to handle null-excluding types (see Process_Formals).
7745 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7747 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7749 -- Ada 2005 (AI-254)
7751 or else Are_Anonymous_Access_To_Subprogram_Types
7754 Desig_1 : Entity_Id;
7755 Desig_2 : Entity_Id;
7758 -- In Ada 2005, access constant indicators must match for
7759 -- subtype conformance.
7761 if Ada_Version >= Ada_2005
7762 and then Ctype >= Subtype_Conformant
7764 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7769 Desig_1 := Find_Designated_Type (Type_1);
7770 Desig_2 := Find_Designated_Type (Type_2);
7772 -- If the context is an instance association for a formal
7773 -- access-to-subprogram type; formal access parameter designated
7774 -- types require mapping because they may denote other formal
7775 -- parameters of the generic unit.
7778 Desig_1 := Get_Instance_Of (Desig_1);
7779 Desig_2 := Get_Instance_Of (Desig_2);
7782 -- It is possible for a Class_Wide_Type to be introduced for an
7783 -- incomplete type, in which case there is a separate class_ wide
7784 -- type for the full view. The types conform if their Etypes
7785 -- conform, i.e. one may be the full view of the other. This can
7786 -- only happen in the context of an access parameter, other uses
7787 -- of an incomplete Class_Wide_Type are illegal.
7789 if Is_Class_Wide_Type (Desig_1)
7791 Is_Class_Wide_Type (Desig_2)
7795 (Etype (Base_Type (Desig_1)),
7796 Etype (Base_Type (Desig_2)), Ctype);
7798 elsif Are_Anonymous_Access_To_Subprogram_Types then
7799 if Ada_Version < Ada_2005 then
7801 Ctype = Type_Conformant
7802 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7804 -- We must check the conformance of the signatures themselves
7808 Conformant : Boolean;
7811 (Desig_1, Desig_2, Ctype, False, Conformant);
7816 -- A limited view of an actual matches the corresponding
7817 -- incomplete formal.
7819 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7820 and then From_Limited_With (Desig_2)
7821 and then Used_As_Generic_Actual (Etype (Desig_2))
7826 return Base_Type (Desig_1) = Base_Type (Desig_2)
7827 and then (Ctype = Type_Conformant
7829 Subtypes_Statically_Match (Desig_1, Desig_2));
7833 -- Otherwise definitely no match
7836 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7837 and then Is_Access_Type (Type_2))
7838 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7839 and then Is_Access_Type (Type_1)))
7842 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7844 May_Hide_Profile := True;
7849 end Conforming_Types;
7851 --------------------------
7852 -- Create_Extra_Formals --
7853 --------------------------
7855 procedure Create_Extra_Formals (E : Entity_Id) is
7856 First_Extra : Entity_Id := Empty;
7858 Last_Extra : Entity_Id := Empty;
7860 function Add_Extra_Formal
7861 (Assoc_Entity : Entity_Id;
7864 Suffix : String) return Entity_Id;
7865 -- Add an extra formal to the current list of formals and extra formals.
7866 -- The extra formal is added to the end of the list of extra formals,
7867 -- and also returned as the result. These formals are always of mode IN.
7868 -- The new formal has the type Typ, is declared in Scope, and its name
7869 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7870 -- The following suffixes are currently used. They should not be changed
7871 -- without coordinating with CodePeer, which makes use of these to
7872 -- provide better messages.
7874 -- O denotes the Constrained bit.
7875 -- L denotes the accessibility level.
7876 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7877 -- the full list in exp_ch6.BIP_Formal_Kind.
7879 ----------------------
7880 -- Add_Extra_Formal --
7881 ----------------------
7883 function Add_Extra_Formal
7884 (Assoc_Entity : Entity_Id;
7887 Suffix : String) return Entity_Id
7889 EF : constant Entity_Id :=
7890 Make_Defining_Identifier (Sloc (Assoc_Entity),
7891 Chars => New_External_Name (Chars (Assoc_Entity),
7895 -- A little optimization. Never generate an extra formal for the
7896 -- _init operand of an initialization procedure, since it could
7899 if Chars (Formal) = Name_uInit then
7903 Set_Ekind (EF, E_In_Parameter);
7904 Set_Actual_Subtype (EF, Typ);
7905 Set_Etype (EF, Typ);
7906 Set_Scope (EF, Scope);
7907 Set_Mechanism (EF, Default_Mechanism);
7908 Set_Formal_Validity (EF);
7910 if No (First_Extra) then
7912 Set_Extra_Formals (Scope, EF);
7915 if Present (Last_Extra) then
7916 Set_Extra_Formal (Last_Extra, EF);
7922 end Add_Extra_Formal;
7926 Formal_Type : Entity_Id;
7927 P_Formal : Entity_Id := Empty;
7929 -- Start of processing for Create_Extra_Formals
7932 -- We never generate extra formals if expansion is not active because we
7933 -- don't need them unless we are generating code.
7935 if not Expander_Active then
7939 -- No need to generate extra formals in interface thunks whose target
7940 -- primitive has no extra formals.
7942 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7946 -- If this is a derived subprogram then the subtypes of the parent
7947 -- subprogram's formal parameters will be used to determine the need
7948 -- for extra formals.
7950 if Is_Overloadable (E) and then Present (Alias (E)) then
7951 P_Formal := First_Formal (Alias (E));
7954 Formal := First_Formal (E);
7955 while Present (Formal) loop
7956 Last_Extra := Formal;
7957 Next_Formal (Formal);
7960 -- If Extra_Formals were already created, don't do it again. This
7961 -- situation may arise for subprogram types created as part of
7962 -- dispatching calls (see Expand_Dispatching_Call).
7964 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7968 -- If the subprogram is a predefined dispatching subprogram then don't
7969 -- generate any extra constrained or accessibility level formals. In
7970 -- general we suppress these for internal subprograms (by not calling
7971 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7972 -- generated stream attributes do get passed through because extra
7973 -- build-in-place formals are needed in some cases (limited 'Input).
7975 if Is_Predefined_Internal_Operation (E) then
7976 goto Test_For_Func_Result_Extras;
7979 Formal := First_Formal (E);
7980 while Present (Formal) loop
7982 -- Create extra formal for supporting the attribute 'Constrained.
7983 -- The case of a private type view without discriminants also
7984 -- requires the extra formal if the underlying type has defaulted
7987 if Ekind (Formal) /= E_In_Parameter then
7988 if Present (P_Formal) then
7989 Formal_Type := Etype (P_Formal);
7991 Formal_Type := Etype (Formal);
7994 -- Do not produce extra formals for Unchecked_Union parameters.
7995 -- Jump directly to the end of the loop.
7997 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7998 goto Skip_Extra_Formal_Generation;
8001 if not Has_Discriminants (Formal_Type)
8002 and then Ekind (Formal_Type) in Private_Kind
8003 and then Present (Underlying_Type (Formal_Type))
8005 Formal_Type := Underlying_Type (Formal_Type);
8008 -- Suppress the extra formal if formal's subtype is constrained or
8009 -- indefinite, or we're compiling for Ada 2012 and the underlying
8010 -- type is tagged and limited. In Ada 2012, a limited tagged type
8011 -- can have defaulted discriminants, but 'Constrained is required
8012 -- to return True, so the formal is never needed (see AI05-0214).
8013 -- Note that this ensures consistency of calling sequences for
8014 -- dispatching operations when some types in a class have defaults
8015 -- on discriminants and others do not (and requiring the extra
8016 -- formal would introduce distributed overhead).
8018 -- If the type does not have a completion yet, treat as prior to
8019 -- Ada 2012 for consistency.
8021 if Has_Discriminants (Formal_Type)
8022 and then not Is_Constrained (Formal_Type)
8023 and then Is_Definite_Subtype (Formal_Type)
8024 and then (Ada_Version < Ada_2012
8025 or else No (Underlying_Type (Formal_Type))
8027 (Is_Limited_Type (Formal_Type)
8030 (Underlying_Type (Formal_Type)))))
8032 Set_Extra_Constrained
8033 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8037 -- Create extra formal for supporting accessibility checking. This
8038 -- is done for both anonymous access formals and formals of named
8039 -- access types that are marked as controlling formals. The latter
8040 -- case can occur when Expand_Dispatching_Call creates a subprogram
8041 -- type and substitutes the types of access-to-class-wide actuals
8042 -- for the anonymous access-to-specific-type of controlling formals.
8043 -- Base_Type is applied because in cases where there is a null
8044 -- exclusion the formal may have an access subtype.
8046 -- This is suppressed if we specifically suppress accessibility
8047 -- checks at the package level for either the subprogram, or the
8048 -- package in which it resides. However, we do not suppress it
8049 -- simply if the scope has accessibility checks suppressed, since
8050 -- this could cause trouble when clients are compiled with a
8051 -- different suppression setting. The explicit checks at the
8052 -- package level are safe from this point of view.
8054 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8055 or else (Is_Controlling_Formal (Formal)
8056 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8058 (Explicit_Suppress (E, Accessibility_Check)
8060 Explicit_Suppress (Scope (E), Accessibility_Check))
8063 or else Present (Extra_Accessibility (P_Formal)))
8065 Set_Extra_Accessibility
8066 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8069 -- This label is required when skipping extra formal generation for
8070 -- Unchecked_Union parameters.
8072 <<Skip_Extra_Formal_Generation>>
8074 if Present (P_Formal) then
8075 Next_Formal (P_Formal);
8078 Next_Formal (Formal);
8081 <<Test_For_Func_Result_Extras>>
8083 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8084 -- function call is ... determined by the point of call ...".
8086 if Needs_Result_Accessibility_Level (E) then
8087 Set_Extra_Accessibility_Of_Result
8088 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8091 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8092 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8094 if Is_Build_In_Place_Function (E) then
8096 Result_Subt : constant Entity_Id := Etype (E);
8097 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8098 Formal_Typ : Entity_Id;
8099 Subp_Decl : Node_Id;
8100 Discard : Entity_Id;
8103 -- In the case of functions with unconstrained result subtypes,
8104 -- add a 4-state formal indicating whether the return object is
8105 -- allocated by the caller (1), or should be allocated by the
8106 -- callee on the secondary stack (2), in the global heap (3), or
8107 -- in a user-defined storage pool (4). For the moment we just use
8108 -- Natural for the type of this formal. Note that this formal
8109 -- isn't usually needed in the case where the result subtype is
8110 -- constrained, but it is needed when the function has a tagged
8111 -- result, because generally such functions can be called in a
8112 -- dispatching context and such calls must be handled like calls
8113 -- to a class-wide function.
8115 if Needs_BIP_Alloc_Form (E) then
8118 (E, Standard_Natural,
8119 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8121 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8122 -- use a user-defined pool. This formal is not added on
8123 -- ZFP as those targets do not support pools.
8125 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8128 (E, RTE (RE_Root_Storage_Pool_Ptr),
8129 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8133 -- In the case of functions whose result type needs finalization,
8134 -- add an extra formal which represents the finalization master.
8136 if Needs_BIP_Finalization_Master (E) then
8139 (E, RTE (RE_Finalization_Master_Ptr),
8140 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8143 -- When the result type contains tasks, add two extra formals: the
8144 -- master of the tasks to be created, and the caller's activation
8147 if Has_Task (Full_Subt) then
8150 (E, RTE (RE_Master_Id),
8151 E, BIP_Formal_Suffix (BIP_Task_Master));
8154 (E, RTE (RE_Activation_Chain_Access),
8155 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8158 -- All build-in-place functions get an extra formal that will be
8159 -- passed the address of the return object within the caller.
8162 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8164 -- Incomplete_View_From_Limited_With is needed here because
8165 -- gigi gets confused if the designated type is the full view
8166 -- coming from a limited-with'ed package. In the normal case,
8167 -- (no limited with) Incomplete_View_From_Limited_With
8168 -- returns Result_Subt.
8170 Set_Directly_Designated_Type
8171 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8172 Set_Etype (Formal_Typ, Formal_Typ);
8173 Set_Depends_On_Private
8174 (Formal_Typ, Has_Private_Component (Formal_Typ));
8175 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8176 Set_Is_Access_Constant (Formal_Typ, False);
8178 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8179 -- the designated type comes from the limited view (for back-end
8182 Set_From_Limited_With
8183 (Formal_Typ, From_Limited_With (Result_Subt));
8185 Layout_Type (Formal_Typ);
8187 -- Force the definition of the Itype in case of internal function
8188 -- calls within the same or nested scope.
8190 if Is_Subprogram_Or_Generic_Subprogram (E) then
8191 Subp_Decl := Parent (E);
8193 -- The insertion point for an Itype reference should be after
8194 -- the unit declaration node of the subprogram. An exception
8195 -- to this are inherited operations from a parent type in which
8196 -- case the derived type acts as their parent.
8198 if Nkind_In (Subp_Decl, N_Function_Specification,
8199 N_Procedure_Specification)
8201 Subp_Decl := Parent (Subp_Decl);
8204 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8209 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8213 -- If this is an instance of a generic, we need to have extra formals
8216 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8217 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8219 end Create_Extra_Formals;
8221 -----------------------------
8222 -- Enter_Overloaded_Entity --
8223 -----------------------------
8225 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8226 function Matches_Predefined_Op return Boolean;
8227 -- This returns an approximation of whether S matches a predefined
8228 -- operator, based on the operator symbol, and the parameter and result
8229 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8231 ---------------------------
8232 -- Matches_Predefined_Op --
8233 ---------------------------
8235 function Matches_Predefined_Op return Boolean is
8236 Formal_1 : constant Entity_Id := First_Formal (S);
8237 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8238 Op : constant Name_Id := Chars (S);
8239 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8240 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8245 if Present (Formal_2) then
8247 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8250 -- All but "&" and "**" have same-types parameters
8259 if Type_1 /= Type_2 then
8264 -- Check parameter and result types
8272 Is_Boolean_Type (Result_Type)
8273 and then Result_Type = Type_1;
8279 Is_Integer_Type (Result_Type)
8280 and then Result_Type = Type_1;
8288 Is_Numeric_Type (Result_Type)
8289 and then Result_Type = Type_1;
8295 Is_Boolean_Type (Result_Type)
8296 and then not Is_Limited_Type (Type_1);
8304 Is_Boolean_Type (Result_Type)
8305 and then (Is_Array_Type (Type_1)
8306 or else Is_Scalar_Type (Type_1));
8308 when Name_Op_Concat =>
8309 return Is_Array_Type (Result_Type);
8311 when Name_Op_Expon =>
8313 (Is_Integer_Type (Result_Type)
8314 or else Is_Floating_Point_Type (Result_Type))
8315 and then Result_Type = Type_1
8316 and then Type_2 = Standard_Integer;
8319 raise Program_Error;
8332 Is_Numeric_Type (Result_Type)
8333 and then Result_Type = Type_1;
8337 Is_Boolean_Type (Result_Type)
8338 and then Result_Type = Type_1;
8341 raise Program_Error;
8344 end Matches_Predefined_Op;
8348 E : Entity_Id := Current_Entity_In_Scope (S);
8349 C_E : Entity_Id := Current_Entity (S);
8351 -- Start of processing for Enter_Overloaded_Entity
8355 Set_Has_Homonym (E);
8356 Set_Has_Homonym (S);
8359 Set_Is_Immediately_Visible (S);
8360 Set_Scope (S, Current_Scope);
8362 -- Chain new entity if front of homonym in current scope, so that
8363 -- homonyms are contiguous.
8365 if Present (E) and then E /= C_E then
8366 while Homonym (C_E) /= E loop
8367 C_E := Homonym (C_E);
8370 Set_Homonym (C_E, S);
8374 Set_Current_Entity (S);
8379 if Is_Inherited_Operation (S) then
8380 Append_Inherited_Subprogram (S);
8382 Append_Entity (S, Current_Scope);
8385 Set_Public_Status (S);
8387 if Debug_Flag_E then
8388 Write_Str ("New overloaded entity chain: ");
8389 Write_Name (Chars (S));
8392 while Present (E) loop
8393 Write_Str (" "); Write_Int (Int (E));
8400 -- Generate warning for hiding
8403 and then Comes_From_Source (S)
8404 and then In_Extended_Main_Source_Unit (S)
8411 -- Warn unless genuine overloading. Do not emit warning on
8412 -- hiding predefined operators in Standard (these are either an
8413 -- (artifact of our implicit declarations, or simple noise) but
8414 -- keep warning on a operator defined on a local subtype, because
8415 -- of the real danger that different operators may be applied in
8416 -- various parts of the program.
8418 -- Note that if E and S have the same scope, there is never any
8419 -- hiding. Either the two conflict, and the program is illegal,
8420 -- or S is overriding an implicit inherited subprogram.
8422 if Scope (E) /= Scope (S)
8423 and then (not Is_Overloadable (E)
8424 or else Subtype_Conformant (E, S))
8425 and then (Is_Immediately_Visible (E)
8426 or else Is_Potentially_Use_Visible (S))
8428 if Scope (E) = Standard_Standard then
8429 if Nkind (S) = N_Defining_Operator_Symbol
8430 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8432 and then Matches_Predefined_Op
8435 ("declaration of & hides predefined operator?h?", S);
8438 -- E not immediately within Standard
8441 Error_Msg_Sloc := Sloc (E);
8442 Error_Msg_N ("declaration of & hides one #?h?", S);
8447 end Enter_Overloaded_Entity;
8449 -----------------------------
8450 -- Check_Untagged_Equality --
8451 -----------------------------
8453 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8454 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8455 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8459 -- This check applies only if we have a subprogram declaration with an
8460 -- untagged record type.
8462 if Nkind (Decl) /= N_Subprogram_Declaration
8463 or else not Is_Record_Type (Typ)
8464 or else Is_Tagged_Type (Typ)
8469 -- In Ada 2012 case, we will output errors or warnings depending on
8470 -- the setting of debug flag -gnatd.E.
8472 if Ada_Version >= Ada_2012 then
8473 Error_Msg_Warn := Debug_Flag_Dot_EE;
8475 -- In earlier versions of Ada, nothing to do unless we are warning on
8476 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8479 if not Warn_On_Ada_2012_Compatibility then
8484 -- Cases where the type has already been frozen
8486 if Is_Frozen (Typ) then
8488 -- If the type is not declared in a package, or if we are in the body
8489 -- of the package or in some other scope, the new operation is not
8490 -- primitive, and therefore legal, though suspicious. Should we
8491 -- generate a warning in this case ???
8493 if Ekind (Scope (Typ)) /= E_Package
8494 or else Scope (Typ) /= Current_Scope
8498 -- If the type is a generic actual (sub)type, the operation is not
8499 -- primitive either because the base type is declared elsewhere.
8501 elsif Is_Generic_Actual_Type (Typ) then
8504 -- Here we have a definite error of declaration after freezing
8507 if Ada_Version >= Ada_2012 then
8509 ("equality operator must be declared before type & is "
8510 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8512 -- In Ada 2012 mode with error turned to warning, output one
8513 -- more warning to warn that the equality operation may not
8514 -- compose. This is the consequence of ignoring the error.
8516 if Error_Msg_Warn then
8517 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8522 ("equality operator must be declared before type& is "
8523 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8526 -- If we are in the package body, we could just move the
8527 -- declaration to the package spec, so add a message saying that.
8529 if In_Package_Body (Scope (Typ)) then
8530 if Ada_Version >= Ada_2012 then
8532 ("\move declaration to package spec<<", Eq_Op);
8535 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8538 -- Otherwise try to find the freezing point
8541 Obj_Decl := Next (Parent (Typ));
8542 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8543 if Nkind (Obj_Decl) = N_Object_Declaration
8544 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8546 -- Freezing point, output warnings
8548 if Ada_Version >= Ada_2012 then
8550 ("type& is frozen by declaration??", Obj_Decl, Typ);
8552 ("\an equality operator cannot be declared after "
8557 ("type& is frozen by declaration (Ada 2012)?y?",
8560 ("\an equality operator cannot be declared after "
8561 & "this point (Ada 2012)?y?",
8573 -- Here if type is not frozen yet. It is illegal to have a primitive
8574 -- equality declared in the private part if the type is visible.
8576 elsif not In_Same_List (Parent (Typ), Decl)
8577 and then not Is_Limited_Type (Typ)
8579 -- Shouldn't we give an RM reference here???
8581 if Ada_Version >= Ada_2012 then
8583 ("equality operator appears too late<<", Eq_Op);
8586 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8589 -- No error detected
8594 end Check_Untagged_Equality;
8596 -----------------------------
8597 -- Find_Corresponding_Spec --
8598 -----------------------------
8600 function Find_Corresponding_Spec
8602 Post_Error : Boolean := True) return Entity_Id
8604 Spec : constant Node_Id := Specification (N);
8605 Designator : constant Entity_Id := Defining_Entity (Spec);
8609 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8610 -- Even if fully conformant, a body may depend on a generic actual when
8611 -- the spec does not, or vice versa, in which case they were distinct
8612 -- entities in the generic.
8614 -------------------------------
8615 -- Different_Generic_Profile --
8616 -------------------------------
8618 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8621 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8622 -- Check that the types of corresponding formals have the same
8623 -- generic actual if any. We have to account for subtypes of a
8624 -- generic formal, declared between a spec and a body, which may
8625 -- appear distinct in an instance but matched in the generic, and
8626 -- the subtype may be used either in the spec or the body of the
8627 -- subprogram being checked.
8629 -------------------------
8630 -- Same_Generic_Actual --
8631 -------------------------
8633 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8635 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8636 -- Predicate to check whether S1 is a subtype of S2 in the source
8639 -------------------------
8640 -- Is_Declared_Subtype --
8641 -------------------------
8643 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8645 return Comes_From_Source (Parent (S1))
8646 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8647 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8648 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8649 end Is_Declared_Subtype;
8651 -- Start of processing for Same_Generic_Actual
8654 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8655 or else Is_Declared_Subtype (T1, T2)
8656 or else Is_Declared_Subtype (T2, T1);
8657 end Same_Generic_Actual;
8659 -- Start of processing for Different_Generic_Profile
8662 if not In_Instance then
8665 elsif Ekind (E) = E_Function
8666 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8671 F1 := First_Formal (Designator);
8672 F2 := First_Formal (E);
8673 while Present (F1) loop
8674 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8683 end Different_Generic_Profile;
8685 -- Start of processing for Find_Corresponding_Spec
8688 E := Current_Entity (Designator);
8689 while Present (E) loop
8691 -- We are looking for a matching spec. It must have the same scope,
8692 -- and the same name, and either be type conformant, or be the case
8693 -- of a library procedure spec and its body (which belong to one
8694 -- another regardless of whether they are type conformant or not).
8696 if Scope (E) = Current_Scope then
8697 if Current_Scope = Standard_Standard
8698 or else (Ekind (E) = Ekind (Designator)
8699 and then Type_Conformant (E, Designator))
8701 -- Within an instantiation, we know that spec and body are
8702 -- subtype conformant, because they were subtype conformant in
8703 -- the generic. We choose the subtype-conformant entity here as
8704 -- well, to resolve spurious ambiguities in the instance that
8705 -- were not present in the generic (i.e. when two different
8706 -- types are given the same actual). If we are looking for a
8707 -- spec to match a body, full conformance is expected.
8711 -- Inherit the convention and "ghostness" of the matching
8712 -- spec to ensure proper full and subtype conformance.
8714 Set_Convention (Designator, Convention (E));
8716 -- Skip past subprogram bodies and subprogram renamings that
8717 -- may appear to have a matching spec, but that aren't fully
8718 -- conformant with it. That can occur in cases where an
8719 -- actual type causes unrelated homographs in the instance.
8721 if Nkind_In (N, N_Subprogram_Body,
8722 N_Subprogram_Renaming_Declaration)
8723 and then Present (Homonym (E))
8724 and then not Fully_Conformant (Designator, E)
8728 elsif not Subtype_Conformant (Designator, E) then
8731 elsif Different_Generic_Profile (E) then
8736 -- Ada 2012 (AI05-0165): For internally generated bodies of
8737 -- null procedures locate the internally generated spec. We
8738 -- enforce mode conformance since a tagged type may inherit
8739 -- from interfaces several null primitives which differ only
8740 -- in the mode of the formals.
8742 if not (Comes_From_Source (E))
8743 and then Is_Null_Procedure (E)
8744 and then not Mode_Conformant (Designator, E)
8748 -- For null procedures coming from source that are completions,
8749 -- analysis of the generated body will establish the link.
8751 elsif Comes_From_Source (E)
8752 and then Nkind (Spec) = N_Procedure_Specification
8753 and then Null_Present (Spec)
8757 -- Expression functions can be completions, but cannot be
8758 -- completed by an explicit body.
8760 elsif Comes_From_Source (E)
8761 and then Comes_From_Source (N)
8762 and then Nkind (N) = N_Subprogram_Body
8763 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8764 N_Expression_Function
8766 Error_Msg_Sloc := Sloc (E);
8767 Error_Msg_N ("body conflicts with expression function#", N);
8770 elsif not Has_Completion (E) then
8771 if Nkind (N) /= N_Subprogram_Body_Stub then
8772 Set_Corresponding_Spec (N, E);
8775 Set_Has_Completion (E);
8778 elsif Nkind (Parent (N)) = N_Subunit then
8780 -- If this is the proper body of a subunit, the completion
8781 -- flag is set when analyzing the stub.
8785 -- If E is an internal function with a controlling result that
8786 -- was created for an operation inherited by a null extension,
8787 -- it may be overridden by a body without a previous spec (one
8788 -- more reason why these should be shunned). In that case we
8789 -- remove the generated body if present, because the current
8790 -- one is the explicit overriding.
8792 elsif Ekind (E) = E_Function
8793 and then Ada_Version >= Ada_2005
8794 and then not Comes_From_Source (E)
8795 and then Has_Controlling_Result (E)
8796 and then Is_Null_Extension (Etype (E))
8797 and then Comes_From_Source (Spec)
8799 Set_Has_Completion (E, False);
8802 and then Nkind (Parent (E)) = N_Function_Specification
8805 (Unit_Declaration_Node
8806 (Corresponding_Body (Unit_Declaration_Node (E))));
8810 -- If expansion is disabled, or if the wrapper function has
8811 -- not been generated yet, this a late body overriding an
8812 -- inherited operation, or it is an overriding by some other
8813 -- declaration before the controlling result is frozen. In
8814 -- either case this is a declaration of a new entity.
8820 -- If the body already exists, then this is an error unless
8821 -- the previous declaration is the implicit declaration of a
8822 -- derived subprogram. It is also legal for an instance to
8823 -- contain type conformant overloadable declarations (but the
8824 -- generic declaration may not), per 8.3(26/2).
8826 elsif No (Alias (E))
8827 and then not Is_Intrinsic_Subprogram (E)
8828 and then not In_Instance
8831 Error_Msg_Sloc := Sloc (E);
8833 if Is_Imported (E) then
8835 ("body not allowed for imported subprogram & declared#",
8838 Error_Msg_NE ("duplicate body for & declared#", N, E);
8842 -- Child units cannot be overloaded, so a conformance mismatch
8843 -- between body and a previous spec is an error.
8845 elsif Is_Child_Unit (E)
8847 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8849 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8854 ("body of child unit does not match previous declaration", N);
8862 -- On exit, we know that no previous declaration of subprogram exists
8865 end Find_Corresponding_Spec;
8867 ----------------------
8868 -- Fully_Conformant --
8869 ----------------------
8871 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8874 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8876 end Fully_Conformant;
8878 ----------------------------------
8879 -- Fully_Conformant_Expressions --
8880 ----------------------------------
8882 function Fully_Conformant_Expressions
8883 (Given_E1 : Node_Id;
8884 Given_E2 : Node_Id) return Boolean
8886 E1 : constant Node_Id := Original_Node (Given_E1);
8887 E2 : constant Node_Id := Original_Node (Given_E2);
8888 -- We always test conformance on original nodes, since it is possible
8889 -- for analysis and/or expansion to make things look as though they
8890 -- conform when they do not, e.g. by converting 1+2 into 3.
8892 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8893 renames Fully_Conformant_Expressions;
8895 function FCL (L1, L2 : List_Id) return Boolean;
8896 -- Compare elements of two lists for conformance. Elements have to be
8897 -- conformant, and actuals inserted as default parameters do not match
8898 -- explicit actuals with the same value.
8900 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8901 -- Compare an operator node with a function call
8907 function FCL (L1, L2 : List_Id) return Boolean is
8911 if L1 = No_List then
8917 if L2 = No_List then
8923 -- Compare two lists, skipping rewrite insertions (we want to compare
8924 -- the original trees, not the expanded versions).
8927 if Is_Rewrite_Insertion (N1) then
8929 elsif Is_Rewrite_Insertion (N2) then
8935 elsif not FCE (N1, N2) then
8948 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8949 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8954 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8959 Act := First (Actuals);
8961 if Nkind (Op_Node) in N_Binary_Op then
8962 if not FCE (Left_Opnd (Op_Node), Act) then
8969 return Present (Act)
8970 and then FCE (Right_Opnd (Op_Node), Act)
8971 and then No (Next (Act));
8975 -- Start of processing for Fully_Conformant_Expressions
8978 -- Nonconformant if paren count does not match. Note: if some idiot
8979 -- complains that we don't do this right for more than 3 levels of
8980 -- parentheses, they will be treated with the respect they deserve.
8982 if Paren_Count (E1) /= Paren_Count (E2) then
8985 -- If same entities are referenced, then they are conformant even if
8986 -- they have different forms (RM 8.3.1(19-20)).
8988 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8989 if Present (Entity (E1)) then
8990 return Entity (E1) = Entity (E2)
8992 -- One may be a discriminant that has been replaced by the
8993 -- corresponding discriminal.
8996 (Chars (Entity (E1)) = Chars (Entity (E2))
8997 and then Ekind (Entity (E1)) = E_Discriminant
8998 and then Ekind (Entity (E2)) = E_In_Parameter)
9000 -- The discriminant of a protected type is transformed into
9001 -- a local constant and then into a parameter of a protected
9005 (Ekind (Entity (E1)) = E_Constant
9006 and then Ekind (Entity (E2)) = E_In_Parameter
9007 and then Present (Discriminal_Link (Entity (E1)))
9008 and then Discriminal_Link (Entity (E1)) =
9009 Discriminal_Link (Entity (E2)))
9011 -- AI12-050: The loop variables of quantified expressions
9012 -- match if they have the same identifier, even though they
9013 -- are different entities.
9016 (Chars (Entity (E1)) = Chars (Entity (E2))
9017 and then Ekind (Entity (E1)) = E_Loop_Parameter
9018 and then Ekind (Entity (E2)) = E_Loop_Parameter);
9020 elsif Nkind (E1) = N_Expanded_Name
9021 and then Nkind (E2) = N_Expanded_Name
9022 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9023 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9025 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9028 -- Identifiers in component associations don't always have
9029 -- entities, but their names must conform.
9031 return Nkind (E1) = N_Identifier
9032 and then Nkind (E2) = N_Identifier
9033 and then Chars (E1) = Chars (E2);
9036 elsif Nkind (E1) = N_Character_Literal
9037 and then Nkind (E2) = N_Expanded_Name
9039 return Nkind (Selector_Name (E2)) = N_Character_Literal
9040 and then Chars (E1) = Chars (Selector_Name (E2));
9042 elsif Nkind (E2) = N_Character_Literal
9043 and then Nkind (E1) = N_Expanded_Name
9045 return Nkind (Selector_Name (E1)) = N_Character_Literal
9046 and then Chars (E2) = Chars (Selector_Name (E1));
9048 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9049 return FCO (E1, E2);
9051 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9052 return FCO (E2, E1);
9054 -- Otherwise we must have the same syntactic entity
9056 elsif Nkind (E1) /= Nkind (E2) then
9059 -- At this point, we specialize by node type
9065 FCL (Expressions (E1), Expressions (E2))
9067 FCL (Component_Associations (E1),
9068 Component_Associations (E2));
9071 if Nkind (Expression (E1)) = N_Qualified_Expression
9073 Nkind (Expression (E2)) = N_Qualified_Expression
9075 return FCE (Expression (E1), Expression (E2));
9077 -- Check that the subtype marks and any constraints
9082 Indic1 : constant Node_Id := Expression (E1);
9083 Indic2 : constant Node_Id := Expression (E2);
9088 if Nkind (Indic1) /= N_Subtype_Indication then
9090 Nkind (Indic2) /= N_Subtype_Indication
9091 and then Entity (Indic1) = Entity (Indic2);
9093 elsif Nkind (Indic2) /= N_Subtype_Indication then
9095 Nkind (Indic1) /= N_Subtype_Indication
9096 and then Entity (Indic1) = Entity (Indic2);
9099 if Entity (Subtype_Mark (Indic1)) /=
9100 Entity (Subtype_Mark (Indic2))
9105 Elt1 := First (Constraints (Constraint (Indic1)));
9106 Elt2 := First (Constraints (Constraint (Indic2)));
9107 while Present (Elt1) and then Present (Elt2) loop
9108 if not FCE (Elt1, Elt2) then
9121 when N_Attribute_Reference =>
9123 Attribute_Name (E1) = Attribute_Name (E2)
9124 and then FCL (Expressions (E1), Expressions (E2));
9128 Entity (E1) = Entity (E2)
9129 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9130 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9132 when N_Membership_Test
9136 FCE (Left_Opnd (E1), Left_Opnd (E2))
9138 FCE (Right_Opnd (E1), Right_Opnd (E2));
9140 when N_Case_Expression =>
9146 if not FCE (Expression (E1), Expression (E2)) then
9150 Alt1 := First (Alternatives (E1));
9151 Alt2 := First (Alternatives (E2));
9153 if Present (Alt1) /= Present (Alt2) then
9155 elsif No (Alt1) then
9159 if not FCE (Expression (Alt1), Expression (Alt2))
9160 or else not FCL (Discrete_Choices (Alt1),
9161 Discrete_Choices (Alt2))
9172 when N_Character_Literal =>
9174 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9176 when N_Component_Association =>
9178 FCL (Choices (E1), Choices (E2))
9180 FCE (Expression (E1), Expression (E2));
9182 when N_Explicit_Dereference =>
9184 FCE (Prefix (E1), Prefix (E2));
9186 when N_Extension_Aggregate =>
9188 FCL (Expressions (E1), Expressions (E2))
9189 and then Null_Record_Present (E1) =
9190 Null_Record_Present (E2)
9191 and then FCL (Component_Associations (E1),
9192 Component_Associations (E2));
9194 when N_Function_Call =>
9196 FCE (Name (E1), Name (E2))
9198 FCL (Parameter_Associations (E1),
9199 Parameter_Associations (E2));
9201 when N_If_Expression =>
9203 FCL (Expressions (E1), Expressions (E2));
9205 when N_Indexed_Component =>
9207 FCE (Prefix (E1), Prefix (E2))
9209 FCL (Expressions (E1), Expressions (E2));
9211 when N_Integer_Literal =>
9212 return (Intval (E1) = Intval (E2));
9217 when N_Operator_Symbol =>
9219 Chars (E1) = Chars (E2);
9221 when N_Others_Choice =>
9224 when N_Parameter_Association =>
9226 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9227 and then FCE (Explicit_Actual_Parameter (E1),
9228 Explicit_Actual_Parameter (E2));
9230 when N_Qualified_Expression
9232 | N_Unchecked_Type_Conversion
9235 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9237 FCE (Expression (E1), Expression (E2));
9239 when N_Quantified_Expression =>
9240 if not FCE (Condition (E1), Condition (E2)) then
9244 if Present (Loop_Parameter_Specification (E1))
9245 and then Present (Loop_Parameter_Specification (E2))
9248 L1 : constant Node_Id :=
9249 Loop_Parameter_Specification (E1);
9250 L2 : constant Node_Id :=
9251 Loop_Parameter_Specification (E2);
9255 Reverse_Present (L1) = Reverse_Present (L2)
9257 FCE (Defining_Identifier (L1),
9258 Defining_Identifier (L2))
9260 FCE (Discrete_Subtype_Definition (L1),
9261 Discrete_Subtype_Definition (L2));
9264 elsif Present (Iterator_Specification (E1))
9265 and then Present (Iterator_Specification (E2))
9268 I1 : constant Node_Id := Iterator_Specification (E1);
9269 I2 : constant Node_Id := Iterator_Specification (E2);
9273 FCE (Defining_Identifier (I1),
9274 Defining_Identifier (I2))
9276 Of_Present (I1) = Of_Present (I2)
9278 Reverse_Present (I1) = Reverse_Present (I2)
9279 and then FCE (Name (I1), Name (I2))
9280 and then FCE (Subtype_Indication (I1),
9281 Subtype_Indication (I2));
9284 -- The quantified expressions used different specifications to
9285 -- walk their respective ranges.
9293 FCE (Low_Bound (E1), Low_Bound (E2))
9295 FCE (High_Bound (E1), High_Bound (E2));
9297 when N_Real_Literal =>
9298 return (Realval (E1) = Realval (E2));
9300 when N_Selected_Component =>
9302 FCE (Prefix (E1), Prefix (E2))
9304 FCE (Selector_Name (E1), Selector_Name (E2));
9308 FCE (Prefix (E1), Prefix (E2))
9310 FCE (Discrete_Range (E1), Discrete_Range (E2));
9312 when N_String_Literal =>
9314 S1 : constant String_Id := Strval (E1);
9315 S2 : constant String_Id := Strval (E2);
9316 L1 : constant Nat := String_Length (S1);
9317 L2 : constant Nat := String_Length (S2);
9324 for J in 1 .. L1 loop
9325 if Get_String_Char (S1, J) /=
9326 Get_String_Char (S2, J)
9338 Entity (E1) = Entity (E2)
9340 FCE (Right_Opnd (E1), Right_Opnd (E2));
9342 -- All other node types cannot appear in this context. Strictly
9343 -- we should raise a fatal internal error. Instead we just ignore
9344 -- the nodes. This means that if anyone makes a mistake in the
9345 -- expander and mucks an expression tree irretrievably, the result
9346 -- will be a failure to detect a (probably very obscure) case
9347 -- of non-conformance, which is better than bombing on some
9348 -- case where two expressions do in fact conform.
9354 end Fully_Conformant_Expressions;
9356 ----------------------------------------
9357 -- Fully_Conformant_Discrete_Subtypes --
9358 ----------------------------------------
9360 function Fully_Conformant_Discrete_Subtypes
9361 (Given_S1 : Node_Id;
9362 Given_S2 : Node_Id) return Boolean
9364 S1 : constant Node_Id := Original_Node (Given_S1);
9365 S2 : constant Node_Id := Original_Node (Given_S2);
9367 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9368 -- Special-case for a bound given by a discriminant, which in the body
9369 -- is replaced with the discriminal of the enclosing type.
9371 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9372 -- Check both bounds
9374 -----------------------
9375 -- Conforming_Bounds --
9376 -----------------------
9378 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9380 if Is_Entity_Name (B1)
9381 and then Is_Entity_Name (B2)
9382 and then Ekind (Entity (B1)) = E_Discriminant
9384 return Chars (B1) = Chars (B2);
9387 return Fully_Conformant_Expressions (B1, B2);
9389 end Conforming_Bounds;
9391 -----------------------
9392 -- Conforming_Ranges --
9393 -----------------------
9395 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9398 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9400 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9401 end Conforming_Ranges;
9403 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9406 if Nkind (S1) /= Nkind (S2) then
9409 elsif Is_Entity_Name (S1) then
9410 return Entity (S1) = Entity (S2);
9412 elsif Nkind (S1) = N_Range then
9413 return Conforming_Ranges (S1, S2);
9415 elsif Nkind (S1) = N_Subtype_Indication then
9417 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9420 (Range_Expression (Constraint (S1)),
9421 Range_Expression (Constraint (S2)));
9425 end Fully_Conformant_Discrete_Subtypes;
9427 --------------------
9428 -- Install_Entity --
9429 --------------------
9431 procedure Install_Entity (E : Entity_Id) is
9432 Prev : constant Entity_Id := Current_Entity (E);
9434 Set_Is_Immediately_Visible (E);
9435 Set_Current_Entity (E);
9436 Set_Homonym (E, Prev);
9439 ---------------------
9440 -- Install_Formals --
9441 ---------------------
9443 procedure Install_Formals (Id : Entity_Id) is
9446 F := First_Formal (Id);
9447 while Present (F) loop
9451 end Install_Formals;
9453 -----------------------------
9454 -- Is_Interface_Conformant --
9455 -----------------------------
9457 function Is_Interface_Conformant
9458 (Tagged_Type : Entity_Id;
9459 Iface_Prim : Entity_Id;
9460 Prim : Entity_Id) return Boolean
9462 -- The operation may in fact be an inherited (implicit) operation
9463 -- rather than the original interface primitive, so retrieve the
9464 -- ultimate ancestor.
9466 Iface : constant Entity_Id :=
9467 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9468 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9470 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9471 -- Return the controlling formal of Prim
9473 ------------------------
9474 -- Controlling_Formal --
9475 ------------------------
9477 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9481 E := First_Entity (Prim);
9482 while Present (E) loop
9483 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9491 end Controlling_Formal;
9495 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9496 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9498 -- Start of processing for Is_Interface_Conformant
9501 pragma Assert (Is_Subprogram (Iface_Prim)
9502 and then Is_Subprogram (Prim)
9503 and then Is_Dispatching_Operation (Iface_Prim)
9504 and then Is_Dispatching_Operation (Prim));
9506 pragma Assert (Is_Interface (Iface)
9507 or else (Present (Alias (Iface_Prim))
9510 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9512 if Prim = Iface_Prim
9513 or else not Is_Subprogram (Prim)
9514 or else Ekind (Prim) /= Ekind (Iface_Prim)
9515 or else not Is_Dispatching_Operation (Prim)
9516 or else Scope (Prim) /= Scope (Tagged_Type)
9518 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9519 or else not Primitive_Names_Match (Iface_Prim, Prim)
9523 -- The mode of the controlling formals must match
9525 elsif Present (Iface_Ctrl_F)
9526 and then Present (Prim_Ctrl_F)
9527 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9531 -- Case of a procedure, or a function whose result type matches the
9532 -- result type of the interface primitive, or a function that has no
9533 -- controlling result (I or access I).
9535 elsif Ekind (Iface_Prim) = E_Procedure
9536 or else Etype (Prim) = Etype (Iface_Prim)
9537 or else not Has_Controlling_Result (Prim)
9539 return Type_Conformant
9540 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9542 -- Case of a function returning an interface, or an access to one. Check
9543 -- that the return types correspond.
9545 elsif Implements_Interface (Typ, Iface) then
9546 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9548 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9553 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9554 Skip_Controlling_Formals => True);
9560 end Is_Interface_Conformant;
9562 ---------------------------------
9563 -- Is_Non_Overriding_Operation --
9564 ---------------------------------
9566 function Is_Non_Overriding_Operation
9567 (Prev_E : Entity_Id;
9568 New_E : Entity_Id) return Boolean
9572 G_Typ : Entity_Id := Empty;
9574 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9575 -- If F_Type is a derived type associated with a generic actual subtype,
9576 -- then return its Generic_Parent_Type attribute, else return Empty.
9578 function Types_Correspond
9579 (P_Type : Entity_Id;
9580 N_Type : Entity_Id) return Boolean;
9581 -- Returns true if and only if the types (or designated types in the
9582 -- case of anonymous access types) are the same or N_Type is derived
9583 -- directly or indirectly from P_Type.
9585 -----------------------------
9586 -- Get_Generic_Parent_Type --
9587 -----------------------------
9589 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9595 if Is_Derived_Type (F_Typ)
9596 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9598 -- The tree must be traversed to determine the parent subtype in
9599 -- the generic unit, which unfortunately isn't always available
9600 -- via semantic attributes. ??? (Note: The use of Original_Node
9601 -- is needed for cases where a full derived type has been
9604 -- If the parent type is a scalar type, the derivation creates
9605 -- an anonymous base type for it, and the source type is its
9608 if Is_Scalar_Type (F_Typ)
9609 and then not Comes_From_Source (F_Typ)
9613 (Original_Node (Parent (First_Subtype (F_Typ))));
9615 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9617 if Nkind (Defn) = N_Derived_Type_Definition then
9618 Indic := Subtype_Indication (Defn);
9620 if Nkind (Indic) = N_Subtype_Indication then
9621 G_Typ := Entity (Subtype_Mark (Indic));
9623 G_Typ := Entity (Indic);
9626 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9627 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9629 return Generic_Parent_Type (Parent (G_Typ));
9635 end Get_Generic_Parent_Type;
9637 ----------------------
9638 -- Types_Correspond --
9639 ----------------------
9641 function Types_Correspond
9642 (P_Type : Entity_Id;
9643 N_Type : Entity_Id) return Boolean
9645 Prev_Type : Entity_Id := Base_Type (P_Type);
9646 New_Type : Entity_Id := Base_Type (N_Type);
9649 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9650 Prev_Type := Designated_Type (Prev_Type);
9653 if Ekind (New_Type) = E_Anonymous_Access_Type then
9654 New_Type := Designated_Type (New_Type);
9657 if Prev_Type = New_Type then
9660 elsif not Is_Class_Wide_Type (New_Type) then
9661 while Etype (New_Type) /= New_Type loop
9662 New_Type := Etype (New_Type);
9664 if New_Type = Prev_Type then
9670 end Types_Correspond;
9672 -- Start of processing for Is_Non_Overriding_Operation
9675 -- In the case where both operations are implicit derived subprograms
9676 -- then neither overrides the other. This can only occur in certain
9677 -- obscure cases (e.g., derivation from homographs created in a generic
9680 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9683 elsif Ekind (Current_Scope) = E_Package
9684 and then Is_Generic_Instance (Current_Scope)
9685 and then In_Private_Part (Current_Scope)
9686 and then Comes_From_Source (New_E)
9688 -- We examine the formals and result type of the inherited operation,
9689 -- to determine whether their type is derived from (the instance of)
9690 -- a generic type. The first such formal or result type is the one
9693 Formal := First_Formal (Prev_E);
9695 while Present (Formal) loop
9696 F_Typ := Base_Type (Etype (Formal));
9698 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9699 F_Typ := Designated_Type (F_Typ);
9702 G_Typ := Get_Generic_Parent_Type (F_Typ);
9703 exit when Present (G_Typ);
9705 Next_Formal (Formal);
9708 -- If the function dispatches on result check the result type
9710 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9711 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9718 -- If the generic type is a private type, then the original operation
9719 -- was not overriding in the generic, because there was no primitive
9720 -- operation to override.
9722 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9723 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9724 N_Formal_Private_Type_Definition
9728 -- The generic parent type is the ancestor of a formal derived
9729 -- type declaration. We need to check whether it has a primitive
9730 -- operation that should be overridden by New_E in the generic.
9734 P_Formal : Entity_Id;
9735 N_Formal : Entity_Id;
9739 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9742 while Present (Prim_Elt) loop
9743 P_Prim := Node (Prim_Elt);
9745 if Chars (P_Prim) = Chars (New_E)
9746 and then Ekind (P_Prim) = Ekind (New_E)
9748 P_Formal := First_Formal (P_Prim);
9749 N_Formal := First_Formal (New_E);
9750 while Present (P_Formal) and then Present (N_Formal) loop
9751 P_Typ := Etype (P_Formal);
9752 N_Typ := Etype (N_Formal);
9754 if not Types_Correspond (P_Typ, N_Typ) then
9758 Next_Entity (P_Formal);
9759 Next_Entity (N_Formal);
9762 -- Found a matching primitive operation belonging to the
9763 -- formal ancestor type, so the new subprogram is
9767 and then No (N_Formal)
9768 and then (Ekind (New_E) /= E_Function
9771 (Etype (P_Prim), Etype (New_E)))
9777 Next_Elmt (Prim_Elt);
9780 -- If no match found, then the new subprogram does not override
9781 -- in the generic (nor in the instance).
9783 -- If the type in question is not abstract, and the subprogram
9784 -- is, this will be an error if the new operation is in the
9785 -- private part of the instance. Emit a warning now, which will
9786 -- make the subsequent error message easier to understand.
9788 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9789 and then Is_Abstract_Subprogram (Prev_E)
9790 and then In_Private_Part (Current_Scope)
9792 Error_Msg_Node_2 := F_Typ;
9794 ("private operation& in generic unit does not override "
9795 & "any primitive operation of& (RM 12.3 (18))??",
9805 end Is_Non_Overriding_Operation;
9807 -------------------------------------
9808 -- List_Inherited_Pre_Post_Aspects --
9809 -------------------------------------
9811 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9813 if Opt.List_Inherited_Aspects
9814 and then Is_Subprogram_Or_Generic_Subprogram (E)
9817 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9822 for Index in Subps'Range loop
9823 Items := Contract (Subps (Index));
9825 if Present (Items) then
9826 Prag := Pre_Post_Conditions (Items);
9827 while Present (Prag) loop
9828 Error_Msg_Sloc := Sloc (Prag);
9830 if Class_Present (Prag)
9831 and then not Split_PPC (Prag)
9833 if Pragma_Name (Prag) = Name_Precondition then
9835 ("info: & inherits `Pre''Class` aspect from "
9839 ("info: & inherits `Post''Class` aspect from "
9844 Prag := Next_Pragma (Prag);
9850 end List_Inherited_Pre_Post_Aspects;
9852 ------------------------------
9853 -- Make_Inequality_Operator --
9854 ------------------------------
9856 -- S is the defining identifier of an equality operator. We build a
9857 -- subprogram declaration with the right signature. This operation is
9858 -- intrinsic, because it is always expanded as the negation of the
9859 -- call to the equality function.
9861 procedure Make_Inequality_Operator (S : Entity_Id) is
9862 Loc : constant Source_Ptr := Sloc (S);
9865 Op_Name : Entity_Id;
9867 FF : constant Entity_Id := First_Formal (S);
9868 NF : constant Entity_Id := Next_Formal (FF);
9871 -- Check that equality was properly defined, ignore call if not
9878 A : constant Entity_Id :=
9879 Make_Defining_Identifier (Sloc (FF),
9880 Chars => Chars (FF));
9882 B : constant Entity_Id :=
9883 Make_Defining_Identifier (Sloc (NF),
9884 Chars => Chars (NF));
9887 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9889 Formals := New_List (
9890 Make_Parameter_Specification (Loc,
9891 Defining_Identifier => A,
9893 New_Occurrence_Of (Etype (First_Formal (S)),
9894 Sloc (Etype (First_Formal (S))))),
9896 Make_Parameter_Specification (Loc,
9897 Defining_Identifier => B,
9899 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9900 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9903 Make_Subprogram_Declaration (Loc,
9905 Make_Function_Specification (Loc,
9906 Defining_Unit_Name => Op_Name,
9907 Parameter_Specifications => Formals,
9908 Result_Definition =>
9909 New_Occurrence_Of (Standard_Boolean, Loc)));
9911 -- Insert inequality right after equality if it is explicit or after
9912 -- the derived type when implicit. These entities are created only
9913 -- for visibility purposes, and eventually replaced in the course
9914 -- of expansion, so they do not need to be attached to the tree and
9915 -- seen by the back-end. Keeping them internal also avoids spurious
9916 -- freezing problems. The declaration is inserted in the tree for
9917 -- analysis, and removed afterwards. If the equality operator comes
9918 -- from an explicit declaration, attach the inequality immediately
9919 -- after. Else the equality is inherited from a derived type
9920 -- declaration, so insert inequality after that declaration.
9922 if No (Alias (S)) then
9923 Insert_After (Unit_Declaration_Node (S), Decl);
9924 elsif Is_List_Member (Parent (S)) then
9925 Insert_After (Parent (S), Decl);
9927 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9930 Mark_Rewrite_Insertion (Decl);
9931 Set_Is_Intrinsic_Subprogram (Op_Name);
9934 Set_Has_Completion (Op_Name);
9935 Set_Corresponding_Equality (Op_Name, S);
9936 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9938 end Make_Inequality_Operator;
9940 ----------------------
9941 -- May_Need_Actuals --
9942 ----------------------
9944 procedure May_Need_Actuals (Fun : Entity_Id) is
9949 F := First_Formal (Fun);
9951 while Present (F) loop
9952 if No (Default_Value (F)) then
9960 Set_Needs_No_Actuals (Fun, B);
9961 end May_Need_Actuals;
9963 ---------------------
9964 -- Mode_Conformant --
9965 ---------------------
9967 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9970 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9972 end Mode_Conformant;
9974 ---------------------------
9975 -- New_Overloaded_Entity --
9976 ---------------------------
9978 procedure New_Overloaded_Entity
9980 Derived_Type : Entity_Id := Empty)
9982 Overridden_Subp : Entity_Id := Empty;
9983 -- Set if the current scope has an operation that is type-conformant
9984 -- with S, and becomes hidden by S.
9986 Is_Primitive_Subp : Boolean;
9987 -- Set to True if the new subprogram is primitive
9990 -- Entity that S overrides
9992 Prev_Vis : Entity_Id := Empty;
9993 -- Predecessor of E in Homonym chain
9995 procedure Check_For_Primitive_Subprogram
9996 (Is_Primitive : out Boolean;
9997 Is_Overriding : Boolean := False);
9998 -- If the subprogram being analyzed is a primitive operation of the type
9999 -- of a formal or result, set the Has_Primitive_Operations flag on the
10000 -- type, and set Is_Primitive to True (otherwise set to False). Set the
10001 -- corresponding flag on the entity itself for later use.
10003 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10004 -- True if a) E is a subprogram whose first formal is a concurrent type
10005 -- defined in the scope of E that has some entry or subprogram whose
10006 -- profile matches E, or b) E is an internally built dispatching
10007 -- subprogram of a protected type and there is a matching subprogram
10008 -- defined in the enclosing scope of the protected type, or c) E is
10009 -- an entry of a synchronized type and a matching procedure has been
10010 -- previously defined in the enclosing scope of the synchronized type.
10012 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10013 -- Check that E is declared in the private part of the current package,
10014 -- or in the package body, where it may hide a previous declaration.
10015 -- We can't use In_Private_Part by itself because this flag is also
10016 -- set when freezing entities, so we must examine the place of the
10017 -- declaration in the tree, and recognize wrapper packages as well.
10019 function Is_Overriding_Alias
10020 (Old_E : Entity_Id;
10021 New_E : Entity_Id) return Boolean;
10022 -- Check whether new subprogram and old subprogram are both inherited
10023 -- from subprograms that have distinct dispatch table entries. This can
10024 -- occur with derivations from instances with accidental homonyms. The
10025 -- function is conservative given that the converse is only true within
10026 -- instances that contain accidental overloadings.
10028 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10029 -- Report conflict between entities S and E
10031 ------------------------------------
10032 -- Check_For_Primitive_Subprogram --
10033 ------------------------------------
10035 procedure Check_For_Primitive_Subprogram
10036 (Is_Primitive : out Boolean;
10037 Is_Overriding : Boolean := False)
10039 Formal : Entity_Id;
10043 function Visible_Part_Type (T : Entity_Id) return Boolean;
10044 -- Returns true if T is declared in the visible part of the current
10045 -- package scope; otherwise returns false. Assumes that T is declared
10048 procedure Check_Private_Overriding (T : Entity_Id);
10049 -- Checks that if a primitive abstract subprogram of a visible
10050 -- abstract type is declared in a private part, then it must override
10051 -- an abstract subprogram declared in the visible part. Also checks
10052 -- that if a primitive function with a controlling result is declared
10053 -- in a private part, then it must override a function declared in
10054 -- the visible part.
10056 ------------------------------
10057 -- Check_Private_Overriding --
10058 ------------------------------
10060 procedure Check_Private_Overriding (T : Entity_Id) is
10061 function Overrides_Private_Part_Op return Boolean;
10062 -- This detects the special case where the overriding subprogram
10063 -- is overriding a subprogram that was declared in the same
10064 -- private part. That case is illegal by 3.9.3(10).
10066 function Overrides_Visible_Function
10067 (Partial_View : Entity_Id) return Boolean;
10068 -- True if S overrides a function in the visible part. The
10069 -- overridden function could be explicitly or implicitly declared.
10071 -------------------------------
10072 -- Overrides_Private_Part_Op --
10073 -------------------------------
10075 function Overrides_Private_Part_Op return Boolean is
10076 Over_Decl : constant Node_Id :=
10077 Unit_Declaration_Node (Overridden_Operation (S));
10078 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10081 pragma Assert (Is_Overriding);
10083 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10085 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10087 return In_Same_List (Over_Decl, Subp_Decl);
10088 end Overrides_Private_Part_Op;
10090 --------------------------------
10091 -- Overrides_Visible_Function --
10092 --------------------------------
10094 function Overrides_Visible_Function
10095 (Partial_View : Entity_Id) return Boolean
10098 if not Is_Overriding or else not Has_Homonym (S) then
10102 if not Present (Partial_View) then
10106 -- Search through all the homonyms H of S in the current
10107 -- package spec, and return True if we find one that matches.
10108 -- Note that Parent (H) will be the declaration of the
10109 -- partial view of T for a match.
10112 H : Entity_Id := S;
10116 exit when not Present (H) or else Scope (H) /= Scope (S);
10120 N_Private_Extension_Declaration,
10121 N_Private_Type_Declaration)
10122 and then Defining_Identifier (Parent (H)) = Partial_View
10130 end Overrides_Visible_Function;
10132 -- Start of processing for Check_Private_Overriding
10135 if Is_Package_Or_Generic_Package (Current_Scope)
10136 and then In_Private_Part (Current_Scope)
10137 and then Visible_Part_Type (T)
10138 and then not In_Instance
10140 if Is_Abstract_Type (T)
10141 and then Is_Abstract_Subprogram (S)
10142 and then (not Is_Overriding
10143 or else not Is_Abstract_Subprogram (E)
10144 or else Overrides_Private_Part_Op)
10147 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10150 elsif Ekind (S) = E_Function then
10152 Partial_View : constant Entity_Id :=
10153 Incomplete_Or_Partial_View (T);
10156 if not Overrides_Visible_Function (Partial_View) then
10158 -- Here, S is "function ... return T;" declared in
10159 -- the private part, not overriding some visible
10160 -- operation. That's illegal in the tagged case
10161 -- (but not if the private type is untagged).
10163 if ((Present (Partial_View)
10164 and then Is_Tagged_Type (Partial_View))
10165 or else (not Present (Partial_View)
10166 and then Is_Tagged_Type (T)))
10167 and then T = Base_Type (Etype (S))
10170 ("private function with tagged result must"
10171 & " override visible-part function", S);
10173 ("\move subprogram to the visible part"
10174 & " (RM 3.9.3(10))", S);
10176 -- AI05-0073: extend this test to the case of a
10177 -- function with a controlling access result.
10179 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10180 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10182 not Is_Class_Wide_Type
10183 (Designated_Type (Etype (S)))
10184 and then Ada_Version >= Ada_2012
10187 ("private function with controlling access "
10188 & "result must override visible-part function",
10191 ("\move subprogram to the visible part"
10192 & " (RM 3.9.3(10))", S);
10198 end Check_Private_Overriding;
10200 -----------------------
10201 -- Visible_Part_Type --
10202 -----------------------
10204 function Visible_Part_Type (T : Entity_Id) return Boolean is
10205 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10208 -- If the entity is a private type, then it must be declared in a
10211 if Ekind (T) in Private_Kind then
10214 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10217 elsif Is_List_Member (Declaration_Node (T))
10218 and then List_Containing (Declaration_Node (T)) =
10219 Visible_Declarations (Specification (P))
10226 end Visible_Part_Type;
10228 -- Start of processing for Check_For_Primitive_Subprogram
10231 Is_Primitive := False;
10233 if not Comes_From_Source (S) then
10236 -- If subprogram is at library level, it is not primitive operation
10238 elsif Current_Scope = Standard_Standard then
10241 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10242 and then not In_Package_Body (Current_Scope))
10243 or else Is_Overriding
10245 -- For function, check return type
10247 if Ekind (S) = E_Function then
10248 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10249 F_Typ := Designated_Type (Etype (S));
10251 F_Typ := Etype (S);
10254 B_Typ := Base_Type (F_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_Has_Primitive_Operations (B_Typ);
10262 Set_Is_Primitive (S);
10263 Check_Private_Overriding (B_Typ);
10265 -- The Ghost policy in effect at the point of declaration
10266 -- or a tagged type and a primitive operation must match
10267 -- (SPARK RM 6.9(16)).
10269 Check_Ghost_Primitive (S, B_Typ);
10273 -- For all subprograms, check formals
10275 Formal := First_Formal (S);
10276 while Present (Formal) loop
10277 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10278 F_Typ := Designated_Type (Etype (Formal));
10280 F_Typ := Etype (Formal);
10283 B_Typ := Base_Type (F_Typ);
10285 if Ekind (B_Typ) = E_Access_Subtype then
10286 B_Typ := Base_Type (B_Typ);
10289 if Scope (B_Typ) = Current_Scope
10290 and then not Is_Class_Wide_Type (B_Typ)
10291 and then not Is_Generic_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
10299 -- of a tagged type and a primitive operation must match
10300 -- (SPARK RM 6.9(16)).
10302 Check_Ghost_Primitive (S, B_Typ);
10305 Next_Formal (Formal);
10308 -- Special case: An equality function can be redefined for a type
10309 -- occurring in a declarative part, and won't otherwise be treated as
10310 -- a primitive because it doesn't occur in a package spec and doesn't
10311 -- override an inherited subprogram. It's important that we mark it
10312 -- primitive so it can be returned by Collect_Primitive_Operations
10313 -- and be used in composing the equality operation of later types
10314 -- that have a component of the type.
10316 elsif Chars (S) = Name_Op_Eq
10317 and then Etype (S) = Standard_Boolean
10319 B_Typ := Base_Type (Etype (First_Formal (S)));
10321 if Scope (B_Typ) = Current_Scope
10323 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10324 and then not Is_Limited_Type (B_Typ)
10326 Is_Primitive := True;
10327 Set_Is_Primitive (S);
10328 Set_Has_Primitive_Operations (B_Typ);
10329 Check_Private_Overriding (B_Typ);
10331 -- The Ghost policy in effect at the point of declaration of a
10332 -- tagged type and a primitive operation must match
10333 -- (SPARK RM 6.9(16)).
10335 Check_Ghost_Primitive (S, B_Typ);
10338 end Check_For_Primitive_Subprogram;
10340 --------------------------------------
10341 -- Has_Matching_Entry_Or_Subprogram --
10342 --------------------------------------
10344 function Has_Matching_Entry_Or_Subprogram
10345 (E : Entity_Id) return Boolean
10347 function Check_Conforming_Parameters
10348 (E1_Param : Node_Id;
10349 E2_Param : Node_Id) return Boolean;
10350 -- Starting from the given parameters, check that all the parameters
10351 -- of two entries or subprograms are subtype conformant. Used to skip
10352 -- the check on the controlling argument.
10354 function Matching_Entry_Or_Subprogram
10355 (Conc_Typ : Entity_Id;
10356 Subp : Entity_Id) return Entity_Id;
10357 -- Return the first entry or subprogram of the given concurrent type
10358 -- whose name matches the name of Subp and has a profile conformant
10359 -- with Subp; return Empty if not found.
10361 function Matching_Dispatching_Subprogram
10362 (Conc_Typ : Entity_Id;
10363 Ent : Entity_Id) return Entity_Id;
10364 -- Return the first dispatching primitive of Conc_Type defined in the
10365 -- enclosing scope of Conc_Type (i.e. before the full definition of
10366 -- this concurrent type) whose name matches the entry Ent and has a
10367 -- profile conformant with the profile of the corresponding (not yet
10368 -- built) dispatching primitive of Ent; return Empty if not found.
10370 function Matching_Original_Protected_Subprogram
10371 (Prot_Typ : Entity_Id;
10372 Subp : Entity_Id) return Entity_Id;
10373 -- Return the first subprogram defined in the enclosing scope of
10374 -- Prot_Typ (before the full definition of this protected type)
10375 -- whose name matches the original name of Subp and has a profile
10376 -- conformant with the profile of Subp; return Empty if not found.
10378 ---------------------------------
10379 -- Check_Conforming_Parameters --
10380 ---------------------------------
10382 function Check_Conforming_Parameters
10383 (E1_Param : Node_Id;
10384 E2_Param : Node_Id) return Boolean
10386 Param_E1 : Node_Id := E1_Param;
10387 Param_E2 : Node_Id := E2_Param;
10390 while Present (Param_E1) and then Present (Param_E2) loop
10391 if Ekind (Defining_Identifier (Param_E1)) /=
10392 Ekind (Defining_Identifier (Param_E2))
10395 (Find_Parameter_Type (Param_E1),
10396 Find_Parameter_Type (Param_E2),
10397 Subtype_Conformant)
10406 -- The candidate is not valid if one of the two lists contains
10407 -- more parameters than the other
10409 return No (Param_E1) and then No (Param_E2);
10410 end Check_Conforming_Parameters;
10412 ----------------------------------
10413 -- Matching_Entry_Or_Subprogram --
10414 ----------------------------------
10416 function Matching_Entry_Or_Subprogram
10417 (Conc_Typ : Entity_Id;
10418 Subp : Entity_Id) return Entity_Id
10423 E := First_Entity (Conc_Typ);
10424 while Present (E) loop
10425 if Chars (Subp) = Chars (E)
10426 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10428 Check_Conforming_Parameters
10429 (First (Parameter_Specifications (Parent (E))),
10430 Next (First (Parameter_Specifications (Parent (Subp)))))
10439 end Matching_Entry_Or_Subprogram;
10441 -------------------------------------
10442 -- Matching_Dispatching_Subprogram --
10443 -------------------------------------
10445 function Matching_Dispatching_Subprogram
10446 (Conc_Typ : Entity_Id;
10447 Ent : Entity_Id) return Entity_Id
10452 -- Search for entities in the enclosing scope of this synchonized
10455 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10456 Push_Scope (Scope (Conc_Typ));
10457 E := Current_Entity_In_Scope (Ent);
10460 while Present (E) loop
10461 if Scope (E) = Scope (Conc_Typ)
10462 and then Comes_From_Source (E)
10463 and then Ekind (E) = E_Procedure
10464 and then Present (First_Entity (E))
10465 and then Is_Controlling_Formal (First_Entity (E))
10466 and then Etype (First_Entity (E)) = Conc_Typ
10468 Check_Conforming_Parameters
10469 (First (Parameter_Specifications (Parent (Ent))),
10470 Next (First (Parameter_Specifications (Parent (E)))))
10479 end Matching_Dispatching_Subprogram;
10481 --------------------------------------------
10482 -- Matching_Original_Protected_Subprogram --
10483 --------------------------------------------
10485 function Matching_Original_Protected_Subprogram
10486 (Prot_Typ : Entity_Id;
10487 Subp : Entity_Id) return Entity_Id
10489 ICF : constant Boolean :=
10490 Is_Controlling_Formal (First_Entity (Subp));
10494 -- Temporarily decorate the first parameter of Subp as controlling
10495 -- formal, required to invoke Subtype_Conformant.
10497 Set_Is_Controlling_Formal (First_Entity (Subp));
10500 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10502 while Present (E) loop
10503 if Scope (E) = Scope (Prot_Typ)
10504 and then Comes_From_Source (E)
10505 and then Ekind (Subp) = Ekind (E)
10506 and then Present (First_Entity (E))
10507 and then Is_Controlling_Formal (First_Entity (E))
10508 and then Etype (First_Entity (E)) = Prot_Typ
10509 and then Subtype_Conformant (Subp, E,
10510 Skip_Controlling_Formals => True)
10512 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10519 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10522 end Matching_Original_Protected_Subprogram;
10524 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10527 -- Case 1: E is a subprogram whose first formal is a concurrent type
10528 -- defined in the scope of E that has an entry or subprogram whose
10529 -- profile matches E.
10531 if Comes_From_Source (E)
10532 and then Is_Subprogram (E)
10533 and then Present (First_Entity (E))
10534 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10537 Scope (Corresponding_Concurrent_Type
10538 (Etype (First_Entity (E))))
10541 (Matching_Entry_Or_Subprogram
10542 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10545 Report_Conflict (E,
10546 Matching_Entry_Or_Subprogram
10547 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10552 -- Case 2: E is an internally built dispatching subprogram of a
10553 -- protected type and there is a subprogram defined in the enclosing
10554 -- scope of the protected type that has the original name of E and
10555 -- its profile is conformant with the profile of E. We check the
10556 -- name of the original protected subprogram associated with E since
10557 -- the expander builds dispatching primitives of protected functions
10558 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10560 elsif not Comes_From_Source (E)
10561 and then Is_Subprogram (E)
10562 and then Present (First_Entity (E))
10563 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10564 and then Present (Original_Protected_Subprogram (E))
10567 (Matching_Original_Protected_Subprogram
10568 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10571 Report_Conflict (E,
10572 Matching_Original_Protected_Subprogram
10573 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10577 -- Case 3: E is an entry of a synchronized type and a matching
10578 -- procedure has been previously defined in the enclosing scope
10579 -- of the synchronized type.
10581 elsif Comes_From_Source (E)
10582 and then Ekind (E) = E_Entry
10584 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10586 Report_Conflict (E,
10587 Matching_Dispatching_Subprogram (Current_Scope, E));
10592 end Has_Matching_Entry_Or_Subprogram;
10594 ----------------------------
10595 -- Is_Private_Declaration --
10596 ----------------------------
10598 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10599 Decl : constant Node_Id := Unit_Declaration_Node (E);
10600 Priv_Decls : List_Id;
10603 if Is_Package_Or_Generic_Package (Current_Scope)
10604 and then In_Private_Part (Current_Scope)
10607 Private_Declarations (Package_Specification (Current_Scope));
10609 return In_Package_Body (Current_Scope)
10611 (Is_List_Member (Decl)
10612 and then List_Containing (Decl) = Priv_Decls)
10613 or else (Nkind (Parent (Decl)) = N_Package_Specification
10615 Is_Compilation_Unit
10616 (Defining_Entity (Parent (Decl)))
10617 and then List_Containing (Parent (Parent (Decl))) =
10622 end Is_Private_Declaration;
10624 --------------------------
10625 -- Is_Overriding_Alias --
10626 --------------------------
10628 function Is_Overriding_Alias
10629 (Old_E : Entity_Id;
10630 New_E : Entity_Id) return Boolean
10632 AO : constant Entity_Id := Alias (Old_E);
10633 AN : constant Entity_Id := Alias (New_E);
10636 return Scope (AO) /= Scope (AN)
10637 or else No (DTC_Entity (AO))
10638 or else No (DTC_Entity (AN))
10639 or else DT_Position (AO) = DT_Position (AN);
10640 end Is_Overriding_Alias;
10642 ---------------------
10643 -- Report_Conflict --
10644 ---------------------
10646 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10648 Error_Msg_Sloc := Sloc (E);
10650 -- Generate message, with useful additional warning if in generic
10652 if Is_Generic_Unit (E) then
10653 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10654 Error_Msg_N ("\& conflicts with declaration#", S);
10656 Error_Msg_N ("& conflicts with declaration#", S);
10658 end Report_Conflict;
10660 -- Start of processing for New_Overloaded_Entity
10663 -- We need to look for an entity that S may override. This must be a
10664 -- homonym in the current scope, so we look for the first homonym of
10665 -- S in the current scope as the starting point for the search.
10667 E := Current_Entity_In_Scope (S);
10669 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10670 -- They are directly added to the list of primitive operations of
10671 -- Derived_Type, unless this is a rederivation in the private part
10672 -- of an operation that was already derived in the visible part of
10673 -- the current package.
10675 if Ada_Version >= Ada_2005
10676 and then Present (Derived_Type)
10677 and then Present (Alias (S))
10678 and then Is_Dispatching_Operation (Alias (S))
10679 and then Present (Find_Dispatching_Type (Alias (S)))
10680 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10682 -- For private types, when the full-view is processed we propagate to
10683 -- the full view the non-overridden entities whose attribute "alias"
10684 -- references an interface primitive. These entities were added by
10685 -- Derive_Subprograms to ensure that interface primitives are
10688 -- Inside_Freeze_Actions is non zero when S corresponds with an
10689 -- internal entity that links an interface primitive with its
10690 -- covering primitive through attribute Interface_Alias (see
10691 -- Add_Internal_Interface_Entities).
10693 if Inside_Freezing_Actions = 0
10694 and then Is_Package_Or_Generic_Package (Current_Scope)
10695 and then In_Private_Part (Current_Scope)
10696 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10697 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10698 and then Full_View (Defining_Identifier (Parent (E)))
10699 = Defining_Identifier (Parent (S))
10700 and then Alias (E) = Alias (S)
10702 Check_Operation_From_Private_View (S, E);
10703 Set_Is_Dispatching_Operation (S);
10708 Enter_Overloaded_Entity (S);
10709 Check_Dispatching_Operation (S, Empty);
10710 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10716 -- For synchronized types check conflicts of this entity with previously
10717 -- defined entities.
10719 if Ada_Version >= Ada_2005
10720 and then Has_Matching_Entry_Or_Subprogram (S)
10725 -- If there is no homonym then this is definitely not overriding
10728 Enter_Overloaded_Entity (S);
10729 Check_Dispatching_Operation (S, Empty);
10730 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10732 -- If subprogram has an explicit declaration, check whether it has an
10733 -- overriding indicator.
10735 if Comes_From_Source (S) then
10736 Check_Synchronized_Overriding (S, Overridden_Subp);
10738 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10739 -- it may have overridden some hidden inherited primitive. Update
10740 -- Overridden_Subp to avoid spurious errors when checking the
10741 -- overriding indicator.
10743 if Ada_Version >= Ada_2012
10744 and then No (Overridden_Subp)
10745 and then Is_Dispatching_Operation (S)
10746 and then Present (Overridden_Operation (S))
10748 Overridden_Subp := Overridden_Operation (S);
10751 Check_Overriding_Indicator
10752 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10754 -- The Ghost policy in effect at the point of declaration of a
10755 -- parent subprogram and an overriding subprogram must match
10756 -- (SPARK RM 6.9(17)).
10758 Check_Ghost_Overriding (S, Overridden_Subp);
10761 -- If there is a homonym that is not overloadable, then we have an
10762 -- error, except for the special cases checked explicitly below.
10764 elsif not Is_Overloadable (E) then
10766 -- Check for spurious conflict produced by a subprogram that has the
10767 -- same name as that of the enclosing generic package. The conflict
10768 -- occurs within an instance, between the subprogram and the renaming
10769 -- declaration for the package. After the subprogram, the package
10770 -- renaming declaration becomes hidden.
10772 if Ekind (E) = E_Package
10773 and then Present (Renamed_Object (E))
10774 and then Renamed_Object (E) = Current_Scope
10775 and then Nkind (Parent (Renamed_Object (E))) =
10776 N_Package_Specification
10777 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10780 Set_Is_Immediately_Visible (E, False);
10781 Enter_Overloaded_Entity (S);
10782 Set_Homonym (S, Homonym (E));
10783 Check_Dispatching_Operation (S, Empty);
10784 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10786 -- If the subprogram is implicit it is hidden by the previous
10787 -- declaration. However if it is dispatching, it must appear in the
10788 -- dispatch table anyway, because it can be dispatched to even if it
10789 -- cannot be called directly.
10791 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10792 Set_Scope (S, Current_Scope);
10794 if Is_Dispatching_Operation (Alias (S)) then
10795 Check_Dispatching_Operation (S, Empty);
10801 Report_Conflict (S, E);
10805 -- E exists and is overloadable
10808 Check_Synchronized_Overriding (S, Overridden_Subp);
10810 -- Loop through E and its homonyms to determine if any of them is
10811 -- the candidate for overriding by S.
10813 while Present (E) loop
10815 -- Definitely not interesting if not in the current scope
10817 if Scope (E) /= Current_Scope then
10820 -- A function can overload the name of an abstract state. The
10821 -- state can be viewed as a function with a profile that cannot
10822 -- be matched by anything.
10824 elsif Ekind (S) = E_Function
10825 and then Ekind (E) = E_Abstract_State
10827 Enter_Overloaded_Entity (S);
10830 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10831 -- procedures locate the internally generated spec. We enforce
10832 -- mode conformance since a tagged type may inherit from
10833 -- interfaces several null primitives which differ only in
10834 -- the mode of the formals.
10836 elsif not Comes_From_Source (S)
10837 and then Is_Null_Procedure (S)
10838 and then not Mode_Conformant (E, S)
10842 -- Check if we have type conformance
10844 elsif Type_Conformant (E, S) then
10846 -- If the old and new entities have the same profile and one
10847 -- is not the body of the other, then this is an error, unless
10848 -- one of them is implicitly declared.
10850 -- There are some cases when both can be implicit, for example
10851 -- when both a literal and a function that overrides it are
10852 -- inherited in a derivation, or when an inherited operation
10853 -- of a tagged full type overrides the inherited operation of
10854 -- a private extension. Ada 83 had a special rule for the
10855 -- literal case. In Ada 95, the later implicit operation hides
10856 -- the former, and the literal is always the former. In the
10857 -- odd case where both are derived operations declared at the
10858 -- same point, both operations should be declared, and in that
10859 -- case we bypass the following test and proceed to the next
10860 -- part. This can only occur for certain obscure cases in
10861 -- instances, when an operation on a type derived from a formal
10862 -- private type does not override a homograph inherited from
10863 -- the actual. In subsequent derivations of such a type, the
10864 -- DT positions of these operations remain distinct, if they
10867 if Present (Alias (S))
10868 and then (No (Alias (E))
10869 or else Comes_From_Source (E)
10870 or else Is_Abstract_Subprogram (S)
10872 (Is_Dispatching_Operation (E)
10873 and then Is_Overriding_Alias (E, S)))
10874 and then Ekind (E) /= E_Enumeration_Literal
10876 -- When an derived operation is overloaded it may be due to
10877 -- the fact that the full view of a private extension
10878 -- re-inherits. It has to be dealt with.
10880 if Is_Package_Or_Generic_Package (Current_Scope)
10881 and then In_Private_Part (Current_Scope)
10883 Check_Operation_From_Private_View (S, E);
10886 -- In any case the implicit operation remains hidden by the
10887 -- existing declaration, which is overriding. Indicate that
10888 -- E overrides the operation from which S is inherited.
10890 if Present (Alias (S)) then
10891 Set_Overridden_Operation (E, Alias (S));
10892 Inherit_Subprogram_Contract (E, Alias (S));
10895 Set_Overridden_Operation (E, S);
10896 Inherit_Subprogram_Contract (E, S);
10899 if Comes_From_Source (E) then
10900 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10902 -- The Ghost policy in effect at the point of declaration
10903 -- of a parent subprogram and an overriding subprogram
10904 -- must match (SPARK RM 6.9(17)).
10906 Check_Ghost_Overriding (E, S);
10911 -- Within an instance, the renaming declarations for actual
10912 -- subprograms may become ambiguous, but they do not hide each
10915 elsif Ekind (E) /= E_Entry
10916 and then not Comes_From_Source (E)
10917 and then not Is_Generic_Instance (E)
10918 and then (Present (Alias (E))
10919 or else Is_Intrinsic_Subprogram (E))
10920 and then (not In_Instance
10921 or else No (Parent (E))
10922 or else Nkind (Unit_Declaration_Node (E)) /=
10923 N_Subprogram_Renaming_Declaration)
10925 -- A subprogram child unit is not allowed to override an
10926 -- inherited subprogram (10.1.1(20)).
10928 if Is_Child_Unit (S) then
10930 ("child unit overrides inherited subprogram in parent",
10935 if Is_Non_Overriding_Operation (E, S) then
10936 Enter_Overloaded_Entity (S);
10938 if No (Derived_Type)
10939 or else Is_Tagged_Type (Derived_Type)
10941 Check_Dispatching_Operation (S, Empty);
10947 -- E is a derived operation or an internal operator which
10948 -- is being overridden. Remove E from further visibility.
10949 -- Furthermore, if E is a dispatching operation, it must be
10950 -- replaced in the list of primitive operations of its type
10951 -- (see Override_Dispatching_Operation).
10953 Overridden_Subp := E;
10959 Prev := First_Entity (Current_Scope);
10960 while Present (Prev) and then Next_Entity (Prev) /= E loop
10961 Next_Entity (Prev);
10964 -- It is possible for E to be in the current scope and
10965 -- yet not in the entity chain. This can only occur in a
10966 -- generic context where E is an implicit concatenation
10967 -- in the formal part, because in a generic body the
10968 -- entity chain starts with the formals.
10970 -- In GNATprove mode, a wrapper for an operation with
10971 -- axiomatization may be a homonym of another declaration
10972 -- for an actual subprogram (needs refinement ???).
10976 and then GNATprove_Mode
10978 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10979 N_Subprogram_Renaming_Declaration
10983 pragma Assert (Chars (E) = Name_Op_Concat);
10988 -- E must be removed both from the entity_list of the
10989 -- current scope, and from the visibility chain.
10991 if Debug_Flag_E then
10992 Write_Str ("Override implicit operation ");
10993 Write_Int (Int (E));
10997 -- If E is a predefined concatenation, it stands for four
10998 -- different operations. As a result, a single explicit
10999 -- declaration does not hide it. In a possible ambiguous
11000 -- situation, Disambiguate chooses the user-defined op,
11001 -- so it is correct to retain the previous internal one.
11003 if Chars (E) /= Name_Op_Concat
11004 or else Ekind (E) /= E_Operator
11006 -- For nondispatching derived operations that are
11007 -- overridden by a subprogram declared in the private
11008 -- part of a package, we retain the derived subprogram
11009 -- but mark it as not immediately visible. If the
11010 -- derived operation was declared in the visible part
11011 -- then this ensures that it will still be visible
11012 -- outside the package with the proper signature
11013 -- (calls from outside must also be directed to this
11014 -- version rather than the overriding one, unlike the
11015 -- dispatching case). Calls from inside the package
11016 -- will still resolve to the overriding subprogram
11017 -- since the derived one is marked as not visible
11018 -- within the package.
11020 -- If the private operation is dispatching, we achieve
11021 -- the overriding by keeping the implicit operation
11022 -- but setting its alias to be the overriding one. In
11023 -- this fashion the proper body is executed in all
11024 -- cases, but the original signature is used outside
11027 -- If the overriding is not in the private part, we
11028 -- remove the implicit operation altogether.
11030 if Is_Private_Declaration (S) then
11031 if not Is_Dispatching_Operation (E) then
11032 Set_Is_Immediately_Visible (E, False);
11034 -- Work done in Override_Dispatching_Operation,
11035 -- so nothing else needs to be done here.
11041 -- Find predecessor of E in Homonym chain
11043 if E = Current_Entity (E) then
11046 Prev_Vis := Current_Entity (E);
11047 while Homonym (Prev_Vis) /= E loop
11048 Prev_Vis := Homonym (Prev_Vis);
11052 if Prev_Vis /= Empty then
11054 -- Skip E in the visibility chain
11056 Set_Homonym (Prev_Vis, Homonym (E));
11059 Set_Name_Entity_Id (Chars (E), Homonym (E));
11062 Set_Next_Entity (Prev, Next_Entity (E));
11064 if No (Next_Entity (Prev)) then
11065 Set_Last_Entity (Current_Scope, Prev);
11070 Enter_Overloaded_Entity (S);
11072 -- For entities generated by Derive_Subprograms the
11073 -- overridden operation is the inherited primitive
11074 -- (which is available through the attribute alias).
11076 if not (Comes_From_Source (E))
11077 and then Is_Dispatching_Operation (E)
11078 and then Find_Dispatching_Type (E) =
11079 Find_Dispatching_Type (S)
11080 and then Present (Alias (E))
11081 and then Comes_From_Source (Alias (E))
11083 Set_Overridden_Operation (S, Alias (E));
11084 Inherit_Subprogram_Contract (S, Alias (E));
11086 -- Normal case of setting entity as overridden
11088 -- Note: Static_Initialization and Overridden_Operation
11089 -- attributes use the same field in subprogram entities.
11090 -- Static_Initialization is only defined for internal
11091 -- initialization procedures, where Overridden_Operation
11092 -- is irrelevant. Therefore the setting of this attribute
11093 -- must check whether the target is an init_proc.
11095 elsif not Is_Init_Proc (S) then
11096 Set_Overridden_Operation (S, E);
11097 Inherit_Subprogram_Contract (S, E);
11100 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11102 -- The Ghost policy in effect at the point of declaration
11103 -- of a parent subprogram and an overriding subprogram
11104 -- must match (SPARK RM 6.9(17)).
11106 Check_Ghost_Overriding (S, E);
11108 -- If S is a user-defined subprogram or a null procedure
11109 -- expanded to override an inherited null procedure, or a
11110 -- predefined dispatching primitive then indicate that E
11111 -- overrides the operation from which S is inherited.
11113 if Comes_From_Source (S)
11115 (Present (Parent (S))
11117 Nkind (Parent (S)) = N_Procedure_Specification
11119 Null_Present (Parent (S)))
11121 (Present (Alias (E))
11123 Is_Predefined_Dispatching_Operation (Alias (E)))
11125 if Present (Alias (E)) then
11126 Set_Overridden_Operation (S, Alias (E));
11127 Inherit_Subprogram_Contract (S, Alias (E));
11131 if Is_Dispatching_Operation (E) then
11133 -- An overriding dispatching subprogram inherits the
11134 -- convention of the overridden subprogram (AI-117).
11136 Set_Convention (S, Convention (E));
11137 Check_Dispatching_Operation (S, E);
11140 Check_Dispatching_Operation (S, Empty);
11143 Check_For_Primitive_Subprogram
11144 (Is_Primitive_Subp, Is_Overriding => True);
11145 goto Check_Inequality;
11148 -- Apparent redeclarations in instances can occur when two
11149 -- formal types get the same actual type. The subprograms in
11150 -- in the instance are legal, even if not callable from the
11151 -- outside. Calls from within are disambiguated elsewhere.
11152 -- For dispatching operations in the visible part, the usual
11153 -- rules apply, and operations with the same profile are not
11154 -- legal (B830001).
11156 elsif (In_Instance_Visible_Part
11157 and then not Is_Dispatching_Operation (E))
11158 or else In_Instance_Not_Visible
11162 -- Here we have a real error (identical profile)
11165 Error_Msg_Sloc := Sloc (E);
11167 -- Avoid cascaded errors if the entity appears in
11168 -- subsequent calls.
11170 Set_Scope (S, Current_Scope);
11172 -- Generate error, with extra useful warning for the case
11173 -- of a generic instance with no completion.
11175 if Is_Generic_Instance (S)
11176 and then not Has_Completion (E)
11179 ("instantiation cannot provide body for&", S);
11180 Error_Msg_N ("\& conflicts with declaration#", S);
11182 Error_Msg_N ("& conflicts with declaration#", S);
11189 -- If one subprogram has an access parameter and the other
11190 -- a parameter of an access type, calls to either might be
11191 -- ambiguous. Verify that parameters match except for the
11192 -- access parameter.
11194 if May_Hide_Profile then
11200 F1 := First_Formal (S);
11201 F2 := First_Formal (E);
11202 while Present (F1) and then Present (F2) loop
11203 if Is_Access_Type (Etype (F1)) then
11204 if not Is_Access_Type (Etype (F2))
11205 or else not Conforming_Types
11206 (Designated_Type (Etype (F1)),
11207 Designated_Type (Etype (F2)),
11210 May_Hide_Profile := False;
11214 not Conforming_Types
11215 (Etype (F1), Etype (F2), Type_Conformant)
11217 May_Hide_Profile := False;
11224 if May_Hide_Profile
11228 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11237 -- On exit, we know that S is a new entity
11239 Enter_Overloaded_Entity (S);
11240 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11241 Check_Overriding_Indicator
11242 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11244 -- The Ghost policy in effect at the point of declaration of a parent
11245 -- subprogram and an overriding subprogram must match
11246 -- (SPARK RM 6.9(17)).
11248 Check_Ghost_Overriding (S, Overridden_Subp);
11250 -- Overloading is not allowed in SPARK, except for operators
11252 if Nkind (S) /= N_Defining_Operator_Symbol then
11253 Error_Msg_Sloc := Sloc (Homonym (S));
11254 Check_SPARK_05_Restriction
11255 ("overloading not allowed with entity#", S);
11258 -- If S is a derived operation for an untagged type then by
11259 -- definition it's not a dispatching operation (even if the parent
11260 -- operation was dispatching), so Check_Dispatching_Operation is not
11261 -- called in that case.
11263 if No (Derived_Type)
11264 or else Is_Tagged_Type (Derived_Type)
11266 Check_Dispatching_Operation (S, Empty);
11270 -- If this is a user-defined equality operator that is not a derived
11271 -- subprogram, create the corresponding inequality. If the operation is
11272 -- dispatching, the expansion is done elsewhere, and we do not create
11273 -- an explicit inequality operation.
11275 <<Check_Inequality>>
11276 if Chars (S) = Name_Op_Eq
11277 and then Etype (S) = Standard_Boolean
11278 and then Present (Parent (S))
11279 and then not Is_Dispatching_Operation (S)
11281 Make_Inequality_Operator (S);
11282 Check_Untagged_Equality (S);
11284 end New_Overloaded_Entity;
11286 ---------------------
11287 -- Process_Formals --
11288 ---------------------
11290 procedure Process_Formals
11292 Related_Nod : Node_Id)
11294 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11295 -- Determine whether an access type designates a type coming from a
11298 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11299 -- Check whether the default has a class-wide type. After analysis the
11300 -- default has the type of the formal, so we must also check explicitly
11301 -- for an access attribute.
11303 ----------------------------------
11304 -- Designates_From_Limited_With --
11305 ----------------------------------
11307 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11308 Desig : Entity_Id := Typ;
11311 if Is_Access_Type (Desig) then
11312 Desig := Directly_Designated_Type (Desig);
11315 if Is_Class_Wide_Type (Desig) then
11316 Desig := Root_Type (Desig);
11320 Ekind (Desig) = E_Incomplete_Type
11321 and then From_Limited_With (Desig);
11322 end Designates_From_Limited_With;
11324 ---------------------------
11325 -- Is_Class_Wide_Default --
11326 ---------------------------
11328 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11330 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11331 or else (Nkind (D) = N_Attribute_Reference
11332 and then Attribute_Name (D) = Name_Access
11333 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11334 end Is_Class_Wide_Default;
11338 Context : constant Node_Id := Parent (Parent (T));
11340 Formal : Entity_Id;
11341 Formal_Type : Entity_Id;
11342 Param_Spec : Node_Id;
11345 Num_Out_Params : Nat := 0;
11346 First_Out_Param : Entity_Id := Empty;
11347 -- Used for setting Is_Only_Out_Parameter
11349 -- Start of processing for Process_Formals
11352 -- In order to prevent premature use of the formals in the same formal
11353 -- part, the Ekind is left undefined until all default expressions are
11354 -- analyzed. The Ekind is established in a separate loop at the end.
11356 Param_Spec := First (T);
11357 while Present (Param_Spec) loop
11358 Formal := Defining_Identifier (Param_Spec);
11359 Set_Never_Set_In_Source (Formal, True);
11360 Enter_Name (Formal);
11362 -- Case of ordinary parameters
11364 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11365 Find_Type (Parameter_Type (Param_Spec));
11366 Ptype := Parameter_Type (Param_Spec);
11368 if Ptype = Error then
11372 Formal_Type := Entity (Ptype);
11374 if Is_Incomplete_Type (Formal_Type)
11376 (Is_Class_Wide_Type (Formal_Type)
11377 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11379 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11380 -- primitive operations, as long as their completion is
11381 -- in the same declarative part. If in the private part
11382 -- this means that the type cannot be a Taft-amendment type.
11383 -- Check is done on package exit. For access to subprograms,
11384 -- the use is legal for Taft-amendment types.
11386 -- Ada 2012: tagged incomplete types are allowed as generic
11387 -- formal types. They do not introduce dependencies and the
11388 -- corresponding generic subprogram does not have a delayed
11389 -- freeze, because it does not need a freeze node. However,
11390 -- it is still the case that untagged incomplete types cannot
11391 -- be Taft-amendment types and must be completed in private
11392 -- part, so the subprogram must appear in the list of private
11393 -- dependents of the type.
11395 if Is_Tagged_Type (Formal_Type)
11396 or else (Ada_Version >= Ada_2012
11397 and then not From_Limited_With (Formal_Type)
11398 and then not Is_Generic_Type (Formal_Type))
11400 if Ekind (Scope (Current_Scope)) = E_Package
11401 and then not Is_Generic_Type (Formal_Type)
11402 and then not Is_Class_Wide_Type (Formal_Type)
11405 (Parent (T), N_Access_Function_Definition,
11406 N_Access_Procedure_Definition)
11408 Append_Elmt (Current_Scope,
11409 Private_Dependents (Base_Type (Formal_Type)));
11411 -- Freezing is delayed to ensure that Register_Prim
11412 -- will get called for this operation, which is needed
11413 -- in cases where static dispatch tables aren't built.
11414 -- (Note that the same is done for controlling access
11415 -- parameter cases in function Access_Definition.)
11417 if not Is_Thunk (Current_Scope) then
11418 Set_Has_Delayed_Freeze (Current_Scope);
11423 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11424 N_Access_Procedure_Definition)
11426 -- AI05-0151: Tagged incomplete types are allowed in all
11427 -- formal parts. Untagged incomplete types are not allowed
11428 -- in bodies. Limited views of either kind are not allowed
11429 -- if there is no place at which the non-limited view can
11430 -- become available.
11432 -- Incomplete formal untagged types are not allowed in
11433 -- subprogram bodies (but are legal in their declarations).
11434 -- This excludes bodies created for null procedures, which
11435 -- are basic declarations.
11437 if Is_Generic_Type (Formal_Type)
11438 and then not Is_Tagged_Type (Formal_Type)
11439 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11442 ("invalid use of formal incomplete type", Param_Spec);
11444 elsif Ada_Version >= Ada_2012 then
11445 if Is_Tagged_Type (Formal_Type)
11446 and then (not From_Limited_With (Formal_Type)
11447 or else not In_Package_Body)
11451 elsif Nkind_In (Context, N_Accept_Statement,
11452 N_Accept_Alternative,
11454 or else (Nkind (Context) = N_Subprogram_Body
11455 and then Comes_From_Source (Context))
11458 ("invalid use of untagged incomplete type &",
11459 Ptype, Formal_Type);
11464 ("invalid use of incomplete type&",
11465 Param_Spec, Formal_Type);
11467 -- Further checks on the legality of incomplete types
11468 -- in formal parts are delayed until the freeze point
11469 -- of the enclosing subprogram or access to subprogram.
11473 elsif Ekind (Formal_Type) = E_Void then
11475 ("premature use of&",
11476 Parameter_Type (Param_Spec), Formal_Type);
11479 -- Ada 2012 (AI-142): Handle aliased parameters
11481 if Ada_Version >= Ada_2012
11482 and then Aliased_Present (Param_Spec)
11484 Set_Is_Aliased (Formal);
11487 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11488 -- declaration corresponding to the null-excluding type of the
11489 -- formal in the enclosing scope. Finally, replace the parameter
11490 -- type of the formal with the internal subtype.
11492 if Ada_Version >= Ada_2005
11493 and then Null_Exclusion_Present (Param_Spec)
11495 if not Is_Access_Type (Formal_Type) then
11497 ("`NOT NULL` allowed only for an access type", Param_Spec);
11500 if Can_Never_Be_Null (Formal_Type)
11501 and then Comes_From_Source (Related_Nod)
11504 ("`NOT NULL` not allowed (& already excludes null)",
11505 Param_Spec, Formal_Type);
11509 Create_Null_Excluding_Itype
11511 Related_Nod => Related_Nod,
11512 Scope_Id => Scope (Current_Scope));
11514 -- If the designated type of the itype is an itype that is
11515 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11516 -- on the access subtype, to prevent order-of-elaboration
11517 -- issues in the backend.
11520 -- type T is access procedure;
11521 -- procedure Op (O : not null T);
11523 if Is_Itype (Directly_Designated_Type (Formal_Type))
11525 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11527 Set_Has_Delayed_Freeze (Formal_Type);
11532 -- An access formal type
11536 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11538 -- No need to continue if we already notified errors
11540 if not Present (Formal_Type) then
11544 -- Ada 2005 (AI-254)
11547 AD : constant Node_Id :=
11548 Access_To_Subprogram_Definition
11549 (Parameter_Type (Param_Spec));
11551 if Present (AD) and then Protected_Present (AD) then
11553 Replace_Anonymous_Access_To_Protected_Subprogram
11559 Set_Etype (Formal, Formal_Type);
11561 -- Deal with default expression if present
11563 Default := Expression (Param_Spec);
11565 if Present (Default) then
11566 Check_SPARK_05_Restriction
11567 ("default expression is not allowed", Default);
11569 if Out_Present (Param_Spec) then
11571 ("default initialization only allowed for IN parameters",
11575 -- Do the special preanalysis of the expression (see section on
11576 -- "Handling of Default Expressions" in the spec of package Sem).
11578 Preanalyze_Spec_Expression (Default, Formal_Type);
11580 -- An access to constant cannot be the default for
11581 -- an access parameter that is an access to variable.
11583 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11584 and then not Is_Access_Constant (Formal_Type)
11585 and then Is_Access_Type (Etype (Default))
11586 and then Is_Access_Constant (Etype (Default))
11589 ("formal that is access to variable cannot be initialized "
11590 & "with an access-to-constant expression", Default);
11593 -- Check that the designated type of an access parameter's default
11594 -- is not a class-wide type unless the parameter's designated type
11595 -- is also class-wide.
11597 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11598 and then not Designates_From_Limited_With (Formal_Type)
11599 and then Is_Class_Wide_Default (Default)
11600 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11603 ("access to class-wide expression not allowed here", Default);
11606 -- Check incorrect use of dynamically tagged expressions
11608 if Is_Tagged_Type (Formal_Type) then
11609 Check_Dynamically_Tagged_Expression
11611 Typ => Formal_Type,
11612 Related_Nod => Default);
11616 -- Ada 2005 (AI-231): Static checks
11618 if Ada_Version >= Ada_2005
11619 and then Is_Access_Type (Etype (Formal))
11620 and then Can_Never_Be_Null (Etype (Formal))
11622 Null_Exclusion_Static_Checks (Param_Spec);
11625 -- The following checks are relevant only when SPARK_Mode is on as
11626 -- these are not standard Ada legality rules.
11628 if SPARK_Mode = On then
11629 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11631 -- A function cannot have a parameter of mode IN OUT or OUT
11634 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11636 ("function cannot have parameter of mode `OUT` or "
11637 & "`IN OUT`", Formal);
11640 -- A procedure cannot have an effectively volatile formal
11641 -- parameter of mode IN because it behaves as a constant
11642 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11644 elsif Ekind (Scope (Formal)) = E_Procedure
11645 and then Ekind (Formal) = E_In_Parameter
11646 and then Is_Effectively_Volatile (Formal)
11649 ("formal parameter of mode `IN` cannot be volatile", Formal);
11657 -- If this is the formal part of a function specification, analyze the
11658 -- subtype mark in the context where the formals are visible but not
11659 -- yet usable, and may hide outer homographs.
11661 if Nkind (Related_Nod) = N_Function_Specification then
11662 Analyze_Return_Type (Related_Nod);
11665 -- Now set the kind (mode) of each formal
11667 Param_Spec := First (T);
11668 while Present (Param_Spec) loop
11669 Formal := Defining_Identifier (Param_Spec);
11670 Set_Formal_Mode (Formal);
11672 if Ekind (Formal) = E_In_Parameter then
11673 Set_Default_Value (Formal, Expression (Param_Spec));
11675 if Present (Expression (Param_Spec)) then
11676 Default := Expression (Param_Spec);
11678 if Is_Scalar_Type (Etype (Default)) then
11679 if Nkind (Parameter_Type (Param_Spec)) /=
11680 N_Access_Definition
11682 Formal_Type := Entity (Parameter_Type (Param_Spec));
11686 (Related_Nod, Parameter_Type (Param_Spec));
11689 Apply_Scalar_Range_Check (Default, Formal_Type);
11693 elsif Ekind (Formal) = E_Out_Parameter then
11694 Num_Out_Params := Num_Out_Params + 1;
11696 if Num_Out_Params = 1 then
11697 First_Out_Param := Formal;
11700 elsif Ekind (Formal) = E_In_Out_Parameter then
11701 Num_Out_Params := Num_Out_Params + 1;
11704 -- Skip remaining processing if formal type was in error
11706 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11707 goto Next_Parameter;
11710 -- Force call by reference if aliased
11713 Conv : constant Convention_Id := Convention (Etype (Formal));
11715 if Is_Aliased (Formal) then
11716 Set_Mechanism (Formal, By_Reference);
11718 -- Warn if user asked this to be passed by copy
11720 if Conv = Convention_Ada_Pass_By_Copy then
11722 ("cannot pass aliased parameter & by copy??", Formal);
11725 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11727 elsif Conv = Convention_Ada_Pass_By_Copy then
11728 Set_Mechanism (Formal, By_Copy);
11730 elsif Conv = Convention_Ada_Pass_By_Reference then
11731 Set_Mechanism (Formal, By_Reference);
11739 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11740 Set_Is_Only_Out_Parameter (First_Out_Param);
11742 end Process_Formals;
11744 ----------------------------
11745 -- Reference_Body_Formals --
11746 ----------------------------
11748 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11753 if Error_Posted (Spec) then
11757 -- Iterate over both lists. They may be of different lengths if the two
11758 -- specs are not conformant.
11760 Fs := First_Formal (Spec);
11761 Fb := First_Formal (Bod);
11762 while Present (Fs) and then Present (Fb) loop
11763 Generate_Reference (Fs, Fb, 'b');
11765 if Style_Check then
11766 Style.Check_Identifier (Fb, Fs);
11769 Set_Spec_Entity (Fb, Fs);
11770 Set_Referenced (Fs, False);
11774 end Reference_Body_Formals;
11776 -------------------------
11777 -- Set_Actual_Subtypes --
11778 -------------------------
11780 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11782 Formal : Entity_Id;
11784 First_Stmt : Node_Id := Empty;
11785 AS_Needed : Boolean;
11788 -- If this is an empty initialization procedure, no need to create
11789 -- actual subtypes (small optimization).
11791 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11794 -- Within a predicate function we do not want to generate local
11795 -- subtypes that may generate nested predicate functions.
11797 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11801 -- The subtype declarations may freeze the formals. The body generated
11802 -- for an expression function is not a freeze point, so do not emit
11803 -- these declarations (small loss of efficiency in rare cases).
11805 if Nkind (N) = N_Subprogram_Body
11806 and then Was_Expression_Function (N)
11811 Formal := First_Formal (Subp);
11812 while Present (Formal) loop
11813 T := Etype (Formal);
11815 -- We never need an actual subtype for a constrained formal
11817 if Is_Constrained (T) then
11818 AS_Needed := False;
11820 -- If we have unknown discriminants, then we do not need an actual
11821 -- subtype, or more accurately we cannot figure it out. Note that
11822 -- all class-wide types have unknown discriminants.
11824 elsif Has_Unknown_Discriminants (T) then
11825 AS_Needed := False;
11827 -- At this stage we have an unconstrained type that may need an
11828 -- actual subtype. For sure the actual subtype is needed if we have
11829 -- an unconstrained array type. However, in an instance, the type
11830 -- may appear as a subtype of the full view, while the actual is
11831 -- in fact private (in which case no actual subtype is needed) so
11832 -- check the kind of the base type.
11834 elsif Is_Array_Type (Base_Type (T)) then
11837 -- The only other case needing an actual subtype is an unconstrained
11838 -- record type which is an IN parameter (we cannot generate actual
11839 -- subtypes for the OUT or IN OUT case, since an assignment can
11840 -- change the discriminant values. However we exclude the case of
11841 -- initialization procedures, since discriminants are handled very
11842 -- specially in this context, see the section entitled "Handling of
11843 -- Discriminants" in Einfo.
11845 -- We also exclude the case of Discrim_SO_Functions (functions used
11846 -- in front-end layout mode for size/offset values), since in such
11847 -- functions only discriminants are referenced, and not only are such
11848 -- subtypes not needed, but they cannot always be generated, because
11849 -- of order of elaboration issues.
11851 elsif Is_Record_Type (T)
11852 and then Ekind (Formal) = E_In_Parameter
11853 and then Chars (Formal) /= Name_uInit
11854 and then not Is_Unchecked_Union (T)
11855 and then not Is_Discrim_SO_Function (Subp)
11859 -- All other cases do not need an actual subtype
11862 AS_Needed := False;
11865 -- Generate actual subtypes for unconstrained arrays and
11866 -- unconstrained discriminated records.
11869 if Nkind (N) = N_Accept_Statement then
11871 -- If expansion is active, the formal is replaced by a local
11872 -- variable that renames the corresponding entry of the
11873 -- parameter block, and it is this local variable that may
11874 -- require an actual subtype.
11876 if Expander_Active then
11877 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11879 Decl := Build_Actual_Subtype (T, Formal);
11882 if Present (Handled_Statement_Sequence (N)) then
11884 First (Statements (Handled_Statement_Sequence (N)));
11885 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11886 Mark_Rewrite_Insertion (Decl);
11888 -- If the accept statement has no body, there will be no
11889 -- reference to the actuals, so no need to compute actual
11896 Decl := Build_Actual_Subtype (T, Formal);
11897 Prepend (Decl, Declarations (N));
11898 Mark_Rewrite_Insertion (Decl);
11901 -- The declaration uses the bounds of an existing object, and
11902 -- therefore needs no constraint checks.
11904 Analyze (Decl, Suppress => All_Checks);
11905 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11907 -- We need to freeze manually the generated type when it is
11908 -- inserted anywhere else than in a declarative part.
11910 if Present (First_Stmt) then
11911 Insert_List_Before_And_Analyze (First_Stmt,
11912 Freeze_Entity (Defining_Identifier (Decl), N));
11914 -- Ditto if the type has a dynamic predicate, because the
11915 -- generated function will mention the actual subtype. The
11916 -- predicate may come from an explicit aspect of be inherited.
11918 elsif Has_Predicates (T) then
11919 Insert_List_Before_And_Analyze (Decl,
11920 Freeze_Entity (Defining_Identifier (Decl), N));
11923 if Nkind (N) = N_Accept_Statement
11924 and then Expander_Active
11926 Set_Actual_Subtype (Renamed_Object (Formal),
11927 Defining_Identifier (Decl));
11929 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11933 Next_Formal (Formal);
11935 end Set_Actual_Subtypes;
11937 ---------------------
11938 -- Set_Formal_Mode --
11939 ---------------------
11941 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11942 Spec : constant Node_Id := Parent (Formal_Id);
11943 Id : constant Entity_Id := Scope (Formal_Id);
11946 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11947 -- since we ensure that corresponding actuals are always valid at the
11948 -- point of the call.
11950 if Out_Present (Spec) then
11951 if Ekind_In (Id, E_Entry, E_Entry_Family)
11952 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11954 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11957 if Ekind_In (Id, E_Function, E_Generic_Function) then
11959 -- [IN] OUT parameters allowed for functions in Ada 2012
11961 if Ada_Version >= Ada_2012 then
11963 -- Even in Ada 2012 operators can only have IN parameters
11965 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11966 Error_Msg_N ("operators can only have IN parameters", Spec);
11969 if In_Present (Spec) then
11970 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11972 Set_Ekind (Formal_Id, E_Out_Parameter);
11975 -- But not in earlier versions of Ada
11978 Error_Msg_N ("functions can only have IN parameters", Spec);
11979 Set_Ekind (Formal_Id, E_In_Parameter);
11982 elsif In_Present (Spec) then
11983 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11986 Set_Ekind (Formal_Id, E_Out_Parameter);
11987 Set_Never_Set_In_Source (Formal_Id, True);
11988 Set_Is_True_Constant (Formal_Id, False);
11989 Set_Current_Value (Formal_Id, Empty);
11993 Set_Ekind (Formal_Id, E_In_Parameter);
11996 -- Set Is_Known_Non_Null for access parameters since the language
11997 -- guarantees that access parameters are always non-null. We also set
11998 -- Can_Never_Be_Null, since there is no way to change the value.
12000 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
12002 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
12003 -- null; In Ada 2005, only if then null_exclusion is explicit.
12005 if Ada_Version < Ada_2005
12006 or else Can_Never_Be_Null (Etype (Formal_Id))
12008 Set_Is_Known_Non_Null (Formal_Id);
12009 Set_Can_Never_Be_Null (Formal_Id);
12012 -- Ada 2005 (AI-231): Null-exclusion access subtype
12014 elsif Is_Access_Type (Etype (Formal_Id))
12015 and then Can_Never_Be_Null (Etype (Formal_Id))
12017 Set_Is_Known_Non_Null (Formal_Id);
12019 -- We can also set Can_Never_Be_Null (thus preventing some junk
12020 -- access checks) for the case of an IN parameter, which cannot
12021 -- be changed, or for an IN OUT parameter, which can be changed but
12022 -- not to a null value. But for an OUT parameter, the initial value
12023 -- passed in can be null, so we can't set this flag in that case.
12025 if Ekind (Formal_Id) /= E_Out_Parameter then
12026 Set_Can_Never_Be_Null (Formal_Id);
12030 Set_Mechanism (Formal_Id, Default_Mechanism);
12031 Set_Formal_Validity (Formal_Id);
12032 end Set_Formal_Mode;
12034 -------------------------
12035 -- Set_Formal_Validity --
12036 -------------------------
12038 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12040 -- If no validity checking, then we cannot assume anything about the
12041 -- validity of parameters, since we do not know there is any checking
12042 -- of the validity on the call side.
12044 if not Validity_Checks_On then
12047 -- If validity checking for parameters is enabled, this means we are
12048 -- not supposed to make any assumptions about argument values.
12050 elsif Validity_Check_Parameters then
12053 -- If we are checking in parameters, we will assume that the caller is
12054 -- also checking parameters, so we can assume the parameter is valid.
12056 elsif Ekind (Formal_Id) = E_In_Parameter
12057 and then Validity_Check_In_Params
12059 Set_Is_Known_Valid (Formal_Id, True);
12061 -- Similar treatment for IN OUT parameters
12063 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12064 and then Validity_Check_In_Out_Params
12066 Set_Is_Known_Valid (Formal_Id, True);
12068 end Set_Formal_Validity;
12070 ------------------------
12071 -- Subtype_Conformant --
12072 ------------------------
12074 function Subtype_Conformant
12075 (New_Id : Entity_Id;
12076 Old_Id : Entity_Id;
12077 Skip_Controlling_Formals : Boolean := False) return Boolean
12081 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12082 Skip_Controlling_Formals => Skip_Controlling_Formals);
12084 end Subtype_Conformant;
12086 ---------------------
12087 -- Type_Conformant --
12088 ---------------------
12090 function Type_Conformant
12091 (New_Id : Entity_Id;
12092 Old_Id : Entity_Id;
12093 Skip_Controlling_Formals : Boolean := False) return Boolean
12097 May_Hide_Profile := False;
12099 (New_Id, Old_Id, Type_Conformant, False, Result,
12100 Skip_Controlling_Formals => Skip_Controlling_Formals);
12102 end Type_Conformant;
12104 -------------------------------
12105 -- Valid_Operator_Definition --
12106 -------------------------------
12108 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12111 Id : constant Name_Id := Chars (Designator);
12115 F := First_Formal (Designator);
12116 while Present (F) loop
12119 if Present (Default_Value (F)) then
12121 ("default values not allowed for operator parameters",
12124 -- For function instantiations that are operators, we must check
12125 -- separately that the corresponding generic only has in-parameters.
12126 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12127 -- an error could not arise in earlier versions of the language.
12129 elsif Ekind (F) /= E_In_Parameter then
12130 Error_Msg_N ("operators can only have IN parameters", F);
12136 -- Verify that user-defined operators have proper number of arguments
12137 -- First case of operators which can only be unary
12139 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12142 -- Case of operators which can be unary or binary
12144 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12145 N_OK := (N in 1 .. 2);
12147 -- All other operators can only be binary
12155 ("incorrect number of arguments for operator", Designator);
12159 and then Base_Type (Etype (Designator)) = Standard_Boolean
12160 and then not Is_Intrinsic_Subprogram (Designator)
12163 ("explicit definition of inequality not allowed", Designator);
12165 end Valid_Operator_Definition;