1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
210 -- Formal_Id is an formal parameter entity. This procedure deals with
211 -- setting the proper validity status for this entity, which depends on
212 -- the kind of parameter and the validity checking mode.
214 ---------------------------------------------
215 -- Analyze_Abstract_Subprogram_Declaration --
216 ---------------------------------------------
218 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
219 Scop : constant Entity_Id := Current_Scope;
220 Subp_Id : constant Entity_Id :=
221 Analyze_Subprogram_Specification (Specification (N));
224 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
226 Generate_Definition (Subp_Id);
228 -- Set the SPARK mode from the current context (may be overwritten later
229 -- with explicit pragma).
231 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
232 Set_SPARK_Pragma_Inherited (Subp_Id);
234 -- Preserve relevant elaboration-related attributes of the context which
235 -- are no longer available or very expensive to recompute once analysis,
236 -- resolution, and expansion are over.
238 Mark_Elaboration_Attributes
243 Set_Is_Abstract_Subprogram (Subp_Id);
244 New_Overloaded_Entity (Subp_Id);
245 Check_Delayed_Subprogram (Subp_Id);
247 Set_Categorization_From_Scope (Subp_Id, Scop);
249 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
250 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
252 -- Issue a warning if the abstract subprogram is neither a dispatching
253 -- operation nor an operation that overrides an inherited subprogram or
254 -- predefined operator, since this most likely indicates a mistake.
256 elsif Warn_On_Redundant_Constructs
257 and then not Is_Dispatching_Operation (Subp_Id)
258 and then not Present (Overridden_Operation (Subp_Id))
259 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
260 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
263 ("abstract subprogram is not dispatching or overriding?r?", N);
266 Generate_Reference_To_Formals (Subp_Id);
267 Check_Eliminated (Subp_Id);
269 if Has_Aspects (N) then
270 Analyze_Aspect_Specifications (N, Subp_Id);
272 end Analyze_Abstract_Subprogram_Declaration;
274 ---------------------------------
275 -- Analyze_Expression_Function --
276 ---------------------------------
278 procedure Analyze_Expression_Function (N : Node_Id) is
279 Expr : constant Node_Id := Expression (N);
280 Loc : constant Source_Ptr := Sloc (N);
281 LocX : constant Source_Ptr := Sloc (Expr);
282 Spec : constant Node_Id := Specification (N);
284 procedure Freeze_Expr_Types (Def_Id : Entity_Id);
285 -- N is an expression function that is a completion and Def_Id its
286 -- defining entity. Freeze before N all the types referenced by the
287 -- expression of the function.
289 -----------------------
290 -- Freeze_Expr_Types --
291 -----------------------
293 procedure Freeze_Expr_Types (Def_Id : Entity_Id) is
294 function Cloned_Expression return Node_Id;
295 -- Build a duplicate of the expression of the return statement that
296 -- has no defining entities shared with the original expression.
298 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result;
299 -- Freeze all types referenced in the subtree rooted at Node
301 -----------------------
302 -- Cloned_Expression --
303 -----------------------
305 function Cloned_Expression return Node_Id is
306 function Clone_Id (Node : Node_Id) return Traverse_Result;
307 -- Tree traversal routine that clones the defining identifier of
308 -- iterator and loop parameter specification nodes.
314 function Clone_Id (Node : Node_Id) return Traverse_Result is
316 if Nkind_In (Node, N_Iterator_Specification,
317 N_Loop_Parameter_Specification)
319 Set_Defining_Identifier (Node,
320 New_Copy (Defining_Identifier (Node)));
326 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id);
330 Dup_Expr : constant Node_Id := New_Copy_Tree (Expr);
332 -- Start of processing for Cloned_Expression
335 -- We must duplicate the expression with semantic information to
336 -- inherit the decoration of global entities in generic instances.
337 -- Set the parent of the new node to be the parent of the original
338 -- to get the proper context, which is needed for complete error
339 -- reporting and for semantic analysis.
341 Set_Parent (Dup_Expr, Parent (Expr));
343 -- Replace the defining identifier of iterators and loop param
344 -- specifications by a clone to ensure that the cloned expression
345 -- and the original expression don't have shared identifiers;
346 -- otherwise, as part of the preanalysis of the expression, these
347 -- shared identifiers may be left decorated with itypes which
348 -- will not be available in the tree passed to the backend.
350 Clone_Def_Ids (Dup_Expr);
353 end Cloned_Expression;
355 ----------------------
356 -- Freeze_Type_Refs --
357 ----------------------
359 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is
360 procedure Check_And_Freeze_Type (Typ : Entity_Id);
361 -- Check that Typ is fully declared and freeze it if so
363 ---------------------------
364 -- Check_And_Freeze_Type --
365 ---------------------------
367 procedure Check_And_Freeze_Type (Typ : Entity_Id) is
369 -- Skip Itypes created by the preanalysis, and itypes whose
370 -- scope is another type (i.e. component subtypes that depend
371 -- on a discriminant),
374 and then (Scope_Within_Or_Same (Scope (Typ), Def_Id)
375 or else Is_Type (Scope (Typ)))
380 -- This provides a better error message than generating
381 -- primitives whose compilation fails much later. Refine
382 -- the error message if possible.
384 Check_Fully_Declared (Typ, Node);
386 if Error_Posted (Node) then
387 if Has_Private_Component (Typ)
388 and then not Is_Private_Type (Typ)
390 Error_Msg_NE ("\type& has private component", Node, Typ);
394 Freeze_Before (N, Typ);
396 end Check_And_Freeze_Type;
398 -- Start of processing for Freeze_Type_Refs
401 -- Check that a type referenced by an entity can be frozen
403 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
404 Check_And_Freeze_Type (Etype (Entity (Node)));
406 -- Check that the enclosing record type can be frozen
408 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
409 Check_And_Freeze_Type (Scope (Entity (Node)));
412 -- Freezing an access type does not freeze the designated type,
413 -- but freezing conversions between access to interfaces requires
414 -- that the interface types themselves be frozen, so that dispatch
415 -- table entities are properly created.
417 -- Unclear whether a more general rule is needed ???
419 elsif Nkind (Node) = N_Type_Conversion
420 and then Is_Access_Type (Etype (Node))
421 and then Is_Interface (Designated_Type (Etype (Node)))
423 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
426 -- An implicit dereference freezes the designated type. In the
427 -- case of a dispatching call whose controlling argument is an
428 -- access type, the dereference is not made explicit, so we must
429 -- check for such a call and freeze the designated type.
431 if Nkind (Node) in N_Has_Etype
432 and then Present (Etype (Node))
433 and then Is_Access_Type (Etype (Node))
434 and then Nkind (Parent (Node)) = N_Function_Call
435 and then Node = Controlling_Argument (Parent (Node))
437 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
440 -- No point in posting several errors on the same expression
442 if Serious_Errors_Detected > 0 then
447 end Freeze_Type_Refs;
449 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs);
453 Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id);
454 Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id);
455 Dup_Expr : constant Node_Id := Cloned_Expression;
457 -- Start of processing for Freeze_Expr_Types
460 -- Preanalyze a duplicate of the expression to have available the
461 -- minimum decoration needed to locate referenced unfrozen types
462 -- without adding any decoration to the function expression.
465 Install_Formals (Def_Id);
467 Preanalyze_Spec_Expression (Dup_Expr, Etype (Def_Id));
470 -- Restore certain attributes of Def_Id since the preanalysis may
471 -- have introduced itypes to this scope, thus modifying attributes
472 -- First_Entity and Last_Entity.
474 Set_First_Entity (Def_Id, Saved_First_Entity);
475 Set_Last_Entity (Def_Id, Saved_Last_Entity);
477 if Present (Last_Entity (Def_Id)) then
478 Set_Next_Entity (Last_Entity (Def_Id), Empty);
481 -- Freeze all types referenced in the expression
483 Freeze_References (Dup_Expr);
484 end Freeze_Expr_Types;
494 Def_Id : Entity_Id := Empty;
496 -- If the expression is a completion, Prev is the entity whose
497 -- declaration is completed. Def_Id is needed to analyze the spec.
499 -- Start of processing for Analyze_Expression_Function
502 -- This is one of the occasions on which we transform the tree during
503 -- semantic analysis. If this is a completion, transform the expression
504 -- function into an equivalent subprogram body, and analyze it.
506 -- Expression functions are inlined unconditionally. The back-end will
507 -- determine whether this is possible.
509 Inline_Processing_Required := True;
511 -- Create a specification for the generated body. This must be done
512 -- prior to the analysis of the initial declaration.
514 New_Spec := Copy_Subprogram_Spec (Spec);
515 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
517 -- If there are previous overloadable entities with the same name,
518 -- check whether any of them is completed by the expression function.
519 -- In a generic context a formal subprogram has no completion.
522 and then Is_Overloadable (Prev)
523 and then not Is_Formal_Subprogram (Prev)
525 Def_Id := Analyze_Subprogram_Specification (Spec);
526 Prev := Find_Corresponding_Spec (N);
528 -- The previous entity may be an expression function as well, in
529 -- which case the redeclaration is illegal.
532 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
533 N_Expression_Function
535 Error_Msg_Sloc := Sloc (Prev);
536 Error_Msg_N ("& conflicts with declaration#", Def_Id);
541 Ret := Make_Simple_Return_Statement (LocX, Expr);
544 Make_Subprogram_Body (Loc,
545 Specification => New_Spec,
546 Declarations => Empty_List,
547 Handled_Statement_Sequence =>
548 Make_Handled_Sequence_Of_Statements (LocX,
549 Statements => New_List (Ret)));
550 Set_Was_Expression_Function (New_Body);
552 -- If the expression completes a generic subprogram, we must create a
553 -- separate node for the body, because at instantiation the original
554 -- node of the generic copy must be a generic subprogram body, and
555 -- cannot be a expression function. Otherwise we just rewrite the
556 -- expression with the non-generic body.
558 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
559 Insert_After (N, New_Body);
561 -- Propagate any aspects or pragmas that apply to the expression
562 -- function to the proper body when the expression function acts
565 if Has_Aspects (N) then
566 Move_Aspects (N, To => New_Body);
569 Relocate_Pragmas_To_Body (New_Body);
571 Rewrite (N, Make_Null_Statement (Loc));
572 Set_Has_Completion (Prev, False);
575 Set_Is_Inlined (Prev);
577 -- If the expression function is a completion, the previous declaration
578 -- must come from source. We know already that it appears in the current
579 -- scope. The entity itself may be internally created if within a body
583 and then Is_Overloadable (Prev)
584 and then not Is_Formal_Subprogram (Prev)
585 and then Comes_From_Source (Parent (Prev))
587 Set_Has_Completion (Prev, False);
588 Set_Is_Inlined (Prev);
590 -- AI12-0103: Expression functions that are a completion freeze their
591 -- expression but don't freeze anything else (unlike regular bodies).
593 -- Note that we cannot defer this freezing to the analysis of the
594 -- expression itself, because a freeze node might appear in a nested
595 -- scope, leading to an elaboration order issue in gigi.
596 -- As elsewhere, we do not emit freeze nodes within a generic unit.
598 if not Inside_A_Generic then
599 Freeze_Expr_Types (Def_Id);
602 -- For navigation purposes, indicate that the function is a body
604 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
605 Rewrite (N, New_Body);
607 -- Remove any existing aspects from the original node because the act
608 -- of rewriting causes the list to be shared between the two nodes.
610 Orig_N := Original_Node (N);
611 Remove_Aspects (Orig_N);
613 -- Propagate any pragmas that apply to expression function to the
614 -- proper body when the expression function acts as a completion.
615 -- Aspects are automatically transfered because of node rewriting.
617 Relocate_Pragmas_To_Body (N);
620 -- Once the aspects of the generated body have been analyzed, create
621 -- a copy for ASIS purposes and associate it with the original node.
623 if Has_Aspects (N) then
624 Set_Aspect_Specifications (Orig_N,
625 New_Copy_List_Tree (Aspect_Specifications (N)));
628 -- Prev is the previous entity with the same name, but it is can
629 -- be an unrelated spec that is not completed by the expression
630 -- function. In that case the relevant entity is the one in the body.
631 -- Not clear that the backend can inline it in this case ???
633 if Has_Completion (Prev) then
635 -- The formals of the expression function are body formals,
636 -- and do not appear in the ali file, which will only contain
637 -- references to the formals of the original subprogram spec.
644 F1 := First_Formal (Def_Id);
645 F2 := First_Formal (Prev);
647 while Present (F1) loop
648 Set_Spec_Entity (F1, F2);
655 Set_Is_Inlined (Defining_Entity (New_Body));
658 -- If this is not a completion, create both a declaration and a body, so
659 -- that the expression can be inlined whenever possible.
662 -- An expression function that is not a completion is not a
663 -- subprogram declaration, and thus cannot appear in a protected
666 if Nkind (Parent (N)) = N_Protected_Definition then
668 ("an expression function is not a legal protected operation", N);
671 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
673 -- Remove any existing aspects from the original node because the act
674 -- of rewriting causes the list to be shared between the two nodes.
676 Orig_N := Original_Node (N);
677 Remove_Aspects (Orig_N);
681 -- Once the aspects of the generated spec have been analyzed, create
682 -- a copy for ASIS purposes and associate it with the original node.
684 if Has_Aspects (N) then
685 Set_Aspect_Specifications (Orig_N,
686 New_Copy_List_Tree (Aspect_Specifications (N)));
689 -- If aspect SPARK_Mode was specified on the body, it needs to be
690 -- repeated both on the generated spec and the body.
692 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
694 if Present (Asp) then
695 Asp := New_Copy_Tree (Asp);
696 Set_Analyzed (Asp, False);
697 Set_Aspect_Specifications (New_Body, New_List (Asp));
700 Def_Id := Defining_Entity (N);
701 Set_Is_Inlined (Def_Id);
703 -- Establish the linkages between the spec and the body. These are
704 -- used when the expression function acts as the prefix of attribute
705 -- 'Access in order to freeze the original expression which has been
706 -- moved to the generated body.
708 Set_Corresponding_Body (N, Defining_Entity (New_Body));
709 Set_Corresponding_Spec (New_Body, Def_Id);
711 -- Within a generic pre-analyze the original expression for name
712 -- capture. The body is also generated but plays no role in
713 -- this because it is not part of the original source.
715 if Inside_A_Generic then
716 Set_Has_Completion (Def_Id);
718 Install_Formals (Def_Id);
719 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
723 -- To prevent premature freeze action, insert the new body at the end
724 -- of the current declarations, or at the end of the package spec.
725 -- However, resolve usage names now, to prevent spurious visibility
726 -- on later entities. Note that the function can now be called in
727 -- the current declarative part, which will appear to be prior to
728 -- the presence of the body in the code. There are nevertheless no
729 -- order of elaboration issues because all name resolution has taken
730 -- place at the point of declaration.
733 Decls : List_Id := List_Containing (N);
734 Expr : constant Node_Id := Expression (Ret);
735 Par : constant Node_Id := Parent (Decls);
736 Typ : constant Entity_Id := Etype (Def_Id);
739 -- If this is a wrapper created for in an instance for a formal
740 -- subprogram, insert body after declaration, to be analyzed when
741 -- the enclosing instance is analyzed.
744 and then Is_Generic_Actual_Subprogram (Def_Id)
746 Insert_After (N, New_Body);
749 if Nkind (Par) = N_Package_Specification
750 and then Decls = Visible_Declarations (Par)
751 and then Present (Private_Declarations (Par))
752 and then not Is_Empty_List (Private_Declarations (Par))
754 Decls := Private_Declarations (Par);
757 Insert_After (Last (Decls), New_Body);
759 -- Preanalyze the expression if not already done above
761 if not Inside_A_Generic then
763 Install_Formals (Def_Id);
764 Preanalyze_Spec_Expression (Expr, Typ);
765 Check_Limited_Return (Original_Node (N), Expr, Typ);
772 -- Check incorrect use of dynamically tagged expression. This doesn't
773 -- fall out automatically when analyzing the generated function body,
774 -- because Check_Dynamically_Tagged_Expression deliberately ignores
775 -- nodes that don't come from source.
778 and then Nkind (Def_Id) in N_Has_Etype
779 and then Is_Tagged_Type (Etype (Def_Id))
781 Check_Dynamically_Tagged_Expression
783 Typ => Etype (Def_Id),
784 Related_Nod => Original_Node (N));
787 -- We must enforce checks for unreferenced formals in our newly
788 -- generated function, so we propagate the referenced flag from the
789 -- original spec to the new spec as well as setting Comes_From_Source.
791 if Present (Parameter_Specifications (New_Spec)) then
793 Form_New_Def : Entity_Id;
794 Form_New_Spec : Entity_Id;
795 Form_Old_Def : Entity_Id;
796 Form_Old_Spec : Entity_Id;
799 Form_New_Spec := First (Parameter_Specifications (New_Spec));
800 Form_Old_Spec := First (Parameter_Specifications (Spec));
802 while Present (Form_New_Spec) and then Present (Form_Old_Spec) loop
803 Form_New_Def := Defining_Identifier (Form_New_Spec);
804 Form_Old_Def := Defining_Identifier (Form_Old_Spec);
806 Set_Comes_From_Source (Form_New_Def, True);
808 -- Because of the usefulness of unreferenced controlling
809 -- formals we exempt them from unreferenced warnings by marking
810 -- them as always referenced.
814 (Is_Formal (Form_Old_Def)
815 and then Is_Controlling_Formal (Form_Old_Def))
816 or else Referenced (Form_Old_Def));
817 -- or else Is_Dispatching_Operation
818 -- (Corresponding_Spec (New_Body)));
820 Next (Form_New_Spec);
821 Next (Form_Old_Spec);
825 end Analyze_Expression_Function;
827 ----------------------------------------
828 -- Analyze_Extended_Return_Statement --
829 ----------------------------------------
831 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
833 Check_Compiler_Unit ("extended return statement", N);
834 Analyze_Return_Statement (N);
835 end Analyze_Extended_Return_Statement;
837 ----------------------------
838 -- Analyze_Function_Call --
839 ----------------------------
841 procedure Analyze_Function_Call (N : Node_Id) is
842 Actuals : constant List_Id := Parameter_Associations (N);
843 Func_Nam : constant Node_Id := Name (N);
849 -- A call of the form A.B (X) may be an Ada 2005 call, which is
850 -- rewritten as B (A, X). If the rewriting is successful, the call
851 -- has been analyzed and we just return.
853 if Nkind (Func_Nam) = N_Selected_Component
854 and then Name (N) /= Func_Nam
855 and then Is_Rewrite_Substitution (N)
856 and then Present (Etype (N))
861 -- If error analyzing name, then set Any_Type as result type and return
863 if Etype (Func_Nam) = Any_Type then
864 Set_Etype (N, Any_Type);
868 -- Otherwise analyze the parameters
870 if Present (Actuals) then
871 Actual := First (Actuals);
872 while Present (Actual) loop
874 Check_Parameterless_Call (Actual);
880 end Analyze_Function_Call;
882 -----------------------------
883 -- Analyze_Function_Return --
884 -----------------------------
886 procedure Analyze_Function_Return (N : Node_Id) is
887 Loc : constant Source_Ptr := Sloc (N);
888 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
889 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
891 R_Type : constant Entity_Id := Etype (Scope_Id);
892 -- Function result subtype
894 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
895 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
896 -- aggregate in a return statement.
898 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
899 -- Check that the return_subtype_indication properly matches the result
900 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
902 -----------------------------------
903 -- Check_Aggregate_Accessibility --
904 -----------------------------------
906 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
907 Typ : constant Entity_Id := Etype (Aggr);
914 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
915 Discr := First_Discriminant (Typ);
916 Assoc := First (Component_Associations (Aggr));
917 while Present (Discr) loop
918 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
919 Expr := Expression (Assoc);
921 if Nkind (Expr) = N_Attribute_Reference
922 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
924 Obj := Prefix (Expr);
925 while Nkind_In (Obj, N_Indexed_Component,
926 N_Selected_Component)
931 -- Do not check aliased formals or function calls. A
932 -- run-time check may still be needed ???
934 if Is_Entity_Name (Obj)
935 and then Comes_From_Source (Obj)
937 if Is_Formal (Entity (Obj))
938 and then Is_Aliased (Entity (Obj))
942 elsif Object_Access_Level (Obj) >
943 Scope_Depth (Scope (Scope_Id))
946 ("access discriminant in return aggregate would "
947 & "be a dangling reference", Obj);
953 Next_Discriminant (Discr);
956 end Check_Aggregate_Accessibility;
958 -------------------------------------
959 -- Check_Return_Subtype_Indication --
960 -------------------------------------
962 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
963 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
965 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
966 -- Subtype given in the extended return statement (must match R_Type)
968 Subtype_Ind : constant Node_Id :=
969 Object_Definition (Original_Node (Obj_Decl));
971 procedure Error_No_Match (N : Node_Id);
972 -- Output error messages for case where types do not statically
973 -- match. N is the location for the messages.
979 procedure Error_No_Match (N : Node_Id) is
982 ("subtype must statically match function result subtype", N);
984 if not Predicates_Match (R_Stm_Type, R_Type) then
985 Error_Msg_Node_2 := R_Type;
987 ("\predicate of& does not match predicate of&",
992 -- Start of processing for Check_Return_Subtype_Indication
995 -- First, avoid cascaded errors
997 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
1001 -- "return access T" case; check that the return statement also has
1002 -- "access T", and that the subtypes statically match:
1003 -- if this is an access to subprogram the signatures must match.
1005 if Is_Anonymous_Access_Type (R_Type) then
1006 if Is_Anonymous_Access_Type (R_Stm_Type) then
1007 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
1009 if Base_Type (Designated_Type (R_Stm_Type)) /=
1010 Base_Type (Designated_Type (R_Type))
1011 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
1013 Error_No_Match (Subtype_Mark (Subtype_Ind));
1017 -- For two anonymous access to subprogram types, the types
1018 -- themselves must be type conformant.
1020 if not Conforming_Types
1021 (R_Stm_Type, R_Type, Fully_Conformant)
1023 Error_No_Match (Subtype_Ind);
1028 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
1031 -- If the return object is of an anonymous access type, then report
1032 -- an error if the function's result type is not also anonymous.
1034 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
1035 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
1037 ("anonymous access not allowed for function with named access "
1038 & "result", Subtype_Ind);
1040 -- Subtype indication case: check that the return object's type is
1041 -- covered by the result type, and that the subtypes statically match
1042 -- when the result subtype is constrained. Also handle record types
1043 -- with unknown discriminants for which we have built the underlying
1044 -- record view. Coverage is needed to allow specific-type return
1045 -- objects when the result type is class-wide (see AI05-32).
1047 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
1048 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1051 (Base_Type (R_Type),
1052 Underlying_Record_View (Base_Type (R_Stm_Type))))
1054 -- A null exclusion may be present on the return type, on the
1055 -- function specification, on the object declaration or on the
1058 if Is_Access_Type (R_Type)
1060 (Can_Never_Be_Null (R_Type)
1061 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1062 Can_Never_Be_Null (R_Stm_Type)
1064 Error_No_Match (Subtype_Ind);
1067 -- AI05-103: for elementary types, subtypes must statically match
1069 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1070 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1071 Error_No_Match (Subtype_Ind);
1075 -- All remaining cases are illegal
1077 -- Note: previous versions of this subprogram allowed the return
1078 -- value to be the ancestor of the return type if the return type
1079 -- was a null extension. This was plainly incorrect.
1083 ("wrong type for return_subtype_indication", Subtype_Ind);
1085 end Check_Return_Subtype_Indication;
1087 ---------------------
1088 -- Local Variables --
1089 ---------------------
1092 Obj_Decl : Node_Id := Empty;
1094 -- Start of processing for Analyze_Function_Return
1097 Set_Return_Present (Scope_Id);
1099 if Nkind (N) = N_Simple_Return_Statement then
1100 Expr := Expression (N);
1102 -- Guard against a malformed expression. The parser may have tried to
1103 -- recover but the node is not analyzable.
1105 if Nkind (Expr) = N_Error then
1106 Set_Etype (Expr, Any_Type);
1107 Expander_Mode_Save_And_Set (False);
1111 -- The resolution of a controlled [extension] aggregate associated
1112 -- with a return statement creates a temporary which needs to be
1113 -- finalized on function exit. Wrap the return statement inside a
1114 -- block so that the finalization machinery can detect this case.
1115 -- This early expansion is done only when the return statement is
1116 -- not part of a handled sequence of statements.
1118 if Nkind_In (Expr, N_Aggregate,
1119 N_Extension_Aggregate)
1120 and then Needs_Finalization (R_Type)
1121 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1124 Make_Block_Statement (Loc,
1125 Handled_Statement_Sequence =>
1126 Make_Handled_Sequence_Of_Statements (Loc,
1127 Statements => New_List (Relocate_Node (N)))));
1135 -- Ada 2005 (AI-251): If the type of the returned object is
1136 -- an access to an interface type then we add an implicit type
1137 -- conversion to force the displacement of the "this" pointer to
1138 -- reference the secondary dispatch table. We cannot delay the
1139 -- generation of this implicit conversion until the expansion
1140 -- because in this case the type resolution changes the decoration
1141 -- of the expression node to match R_Type; by contrast, if the
1142 -- returned object is a class-wide interface type then it is too
1143 -- early to generate here the implicit conversion since the return
1144 -- statement may be rewritten by the expander into an extended
1145 -- return statement whose expansion takes care of adding the
1146 -- implicit type conversion to displace the pointer to the object.
1149 and then Serious_Errors_Detected = 0
1150 and then Is_Access_Type (R_Type)
1151 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1152 and then Is_Interface (Designated_Type (R_Type))
1153 and then Is_Progenitor (Designated_Type (R_Type),
1154 Designated_Type (Etype (Expr)))
1156 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1160 Resolve (Expr, R_Type);
1161 Check_Limited_Return (N, Expr, R_Type);
1163 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
1164 Check_Aggregate_Accessibility (Expr);
1168 -- RETURN only allowed in SPARK as the last statement in function
1170 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1172 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1173 or else Present (Next (N)))
1175 Check_SPARK_05_Restriction
1176 ("RETURN should be the last statement in function", N);
1180 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1181 Obj_Decl := Last (Return_Object_Declarations (N));
1183 -- Analyze parts specific to extended_return_statement:
1186 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1187 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1190 Expr := Expression (Obj_Decl);
1192 -- Note: The check for OK_For_Limited_Init will happen in
1193 -- Analyze_Object_Declaration; we treat it as a normal
1194 -- object declaration.
1196 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1199 Check_Return_Subtype_Indication (Obj_Decl);
1201 if Present (HSS) then
1204 if Present (Exception_Handlers (HSS)) then
1206 -- ???Has_Nested_Block_With_Handler needs to be set.
1207 -- Probably by creating an actual N_Block_Statement.
1208 -- Probably in Expand.
1214 -- Mark the return object as referenced, since the return is an
1215 -- implicit reference of the object.
1217 Set_Referenced (Defining_Identifier (Obj_Decl));
1219 Check_References (Stm_Entity);
1221 -- Check RM 6.5 (5.9/3)
1224 if Ada_Version < Ada_2012 then
1226 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1227 -- Can it really happen (extended return???)
1230 ("aliased only allowed for limited return objects "
1231 & "in Ada 2012??", N);
1233 elsif not Is_Limited_View (R_Type) then
1235 ("aliased only allowed for limited return objects", N);
1241 -- Case of Expr present
1243 if Present (Expr) then
1245 -- Defend against previous errors
1247 if Nkind (Expr) = N_Empty
1248 or else No (Etype (Expr))
1253 -- Apply constraint check. Note that this is done before the implicit
1254 -- conversion of the expression done for anonymous access types to
1255 -- ensure correct generation of the null-excluding check associated
1256 -- with null-excluding expressions found in return statements.
1258 Apply_Constraint_Check (Expr, R_Type);
1260 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1261 -- type, apply an implicit conversion of the expression to that type
1262 -- to force appropriate static and run-time accessibility checks.
1264 if Ada_Version >= Ada_2005
1265 and then Ekind (R_Type) = E_Anonymous_Access_Type
1267 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1268 Analyze_And_Resolve (Expr, R_Type);
1270 -- If this is a local anonymous access to subprogram, the
1271 -- accessibility check can be applied statically. The return is
1272 -- illegal if the access type of the return expression is declared
1273 -- inside of the subprogram (except if it is the subtype indication
1274 -- of an extended return statement).
1276 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1277 if not Comes_From_Source (Current_Scope)
1278 or else Ekind (Current_Scope) = E_Return_Statement
1283 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1285 Error_Msg_N ("cannot return local access to subprogram", N);
1288 -- The expression cannot be of a formal incomplete type
1290 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1291 and then Is_Generic_Type (Etype (Expr))
1294 ("cannot return expression of a formal incomplete type", N);
1297 -- If the result type is class-wide, then check that the return
1298 -- expression's type is not declared at a deeper level than the
1299 -- function (RM05-6.5(5.6/2)).
1301 if Ada_Version >= Ada_2005
1302 and then Is_Class_Wide_Type (R_Type)
1304 if Type_Access_Level (Etype (Expr)) >
1305 Subprogram_Access_Level (Scope_Id)
1308 ("level of return expression type is deeper than "
1309 & "class-wide function!", Expr);
1313 -- Check incorrect use of dynamically tagged expression
1315 if Is_Tagged_Type (R_Type) then
1316 Check_Dynamically_Tagged_Expression
1322 -- ??? A real run-time accessibility check is needed in cases
1323 -- involving dereferences of access parameters. For now we just
1324 -- check the static cases.
1326 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1327 and then Is_Limited_View (Etype (Scope_Id))
1328 and then Object_Access_Level (Expr) >
1329 Subprogram_Access_Level (Scope_Id)
1331 -- Suppress the message in a generic, where the rewriting
1334 if Inside_A_Generic then
1339 Make_Raise_Program_Error (Loc,
1340 Reason => PE_Accessibility_Check_Failed));
1343 Error_Msg_Warn := SPARK_Mode /= On;
1344 Error_Msg_N ("cannot return a local value by reference<<", N);
1345 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1349 if Known_Null (Expr)
1350 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1351 and then Null_Exclusion_Present (Parent (Scope_Id))
1353 Apply_Compile_Time_Constraint_Error
1355 Msg => "(Ada 2005) null not allowed for "
1356 & "null-excluding return??",
1357 Reason => CE_Null_Not_Allowed);
1360 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1361 -- has no initializing expression.
1363 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1364 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1365 Subprogram_Access_Level (Scope_Id)
1368 ("level of return expression type is deeper than "
1369 & "class-wide function!", Obj_Decl);
1372 end Analyze_Function_Return;
1374 -------------------------------------
1375 -- Analyze_Generic_Subprogram_Body --
1376 -------------------------------------
1378 procedure Analyze_Generic_Subprogram_Body
1382 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1383 Kind : constant Entity_Kind := Ekind (Gen_Id);
1384 Body_Id : Entity_Id;
1389 -- Copy body and disable expansion while analyzing the generic For a
1390 -- stub, do not copy the stub (which would load the proper body), this
1391 -- will be done when the proper body is analyzed.
1393 if Nkind (N) /= N_Subprogram_Body_Stub then
1394 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1397 -- Once the contents of the generic copy and the template are
1398 -- swapped, do the same for their respective aspect specifications.
1400 Exchange_Aspects (N, New_N);
1402 -- Collect all contract-related source pragmas found within the
1403 -- template and attach them to the contract of the subprogram body.
1404 -- This contract is used in the capture of global references within
1407 Create_Generic_Contract (N);
1412 Spec := Specification (N);
1414 -- Within the body of the generic, the subprogram is callable, and
1415 -- behaves like the corresponding non-generic unit.
1417 Body_Id := Defining_Entity (Spec);
1419 if Kind = E_Generic_Procedure
1420 and then Nkind (Spec) /= N_Procedure_Specification
1422 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1425 elsif Kind = E_Generic_Function
1426 and then Nkind (Spec) /= N_Function_Specification
1428 Error_Msg_N ("invalid body for generic function ", Body_Id);
1432 Set_Corresponding_Body (Gen_Decl, Body_Id);
1434 if Has_Completion (Gen_Id)
1435 and then Nkind (Parent (N)) /= N_Subunit
1437 Error_Msg_N ("duplicate generic body", N);
1440 Set_Has_Completion (Gen_Id);
1443 if Nkind (N) = N_Subprogram_Body_Stub then
1444 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1446 Set_Corresponding_Spec (N, Gen_Id);
1449 if Nkind (Parent (N)) = N_Compilation_Unit then
1450 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1453 -- Make generic parameters immediately visible in the body. They are
1454 -- needed to process the formals declarations. Then make the formals
1455 -- visible in a separate step.
1457 Push_Scope (Gen_Id);
1461 First_Ent : Entity_Id;
1464 First_Ent := First_Entity (Gen_Id);
1467 while Present (E) and then not Is_Formal (E) loop
1472 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1474 -- Now generic formals are visible, and the specification can be
1475 -- analyzed, for subsequent conformance check.
1477 Body_Id := Analyze_Subprogram_Specification (Spec);
1479 -- Make formal parameters visible
1483 -- E is the first formal parameter, we loop through the formals
1484 -- installing them so that they will be visible.
1486 Set_First_Entity (Gen_Id, E);
1487 while Present (E) loop
1493 -- Visible generic entity is callable within its own body
1495 Set_Ekind (Gen_Id, Ekind (Body_Id));
1496 Set_Ekind (Body_Id, E_Subprogram_Body);
1497 Set_Convention (Body_Id, Convention (Gen_Id));
1498 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1499 Set_Scope (Body_Id, Scope (Gen_Id));
1501 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1503 if Nkind (N) = N_Subprogram_Body_Stub then
1505 -- No body to analyze, so restore state of generic unit
1507 Set_Ekind (Gen_Id, Kind);
1508 Set_Ekind (Body_Id, Kind);
1510 if Present (First_Ent) then
1511 Set_First_Entity (Gen_Id, First_Ent);
1518 -- If this is a compilation unit, it must be made visible explicitly,
1519 -- because the compilation of the declaration, unlike other library
1520 -- unit declarations, does not. If it is not a unit, the following
1521 -- is redundant but harmless.
1523 Set_Is_Immediately_Visible (Gen_Id);
1524 Reference_Body_Formals (Gen_Id, Body_Id);
1526 if Is_Child_Unit (Gen_Id) then
1527 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1530 Set_Actual_Subtypes (N, Current_Scope);
1532 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1533 Set_SPARK_Pragma_Inherited (Body_Id);
1535 -- Analyze any aspect specifications that appear on the generic
1538 if Has_Aspects (N) then
1539 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1542 Analyze_Declarations (Declarations (N));
1545 -- Process the contract of the subprogram body after all declarations
1546 -- have been analyzed. This ensures that any contract-related pragmas
1547 -- are available through the N_Contract node of the body.
1549 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1551 Analyze (Handled_Statement_Sequence (N));
1552 Save_Global_References (Original_Node (N));
1554 -- Prior to exiting the scope, include generic formals again (if any
1555 -- are present) in the set of local entities.
1557 if Present (First_Ent) then
1558 Set_First_Entity (Gen_Id, First_Ent);
1561 Check_References (Gen_Id);
1564 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1565 Update_Use_Clause_Chain;
1566 Validate_Categorization_Dependency (N, Gen_Id);
1568 Check_Subprogram_Order (N);
1570 -- Outside of its body, unit is generic again
1572 Set_Ekind (Gen_Id, Kind);
1573 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1576 Style.Check_Identifier (Body_Id, Gen_Id);
1580 end Analyze_Generic_Subprogram_Body;
1582 ----------------------------
1583 -- Analyze_Null_Procedure --
1584 ----------------------------
1586 procedure Analyze_Null_Procedure
1588 Is_Completion : out Boolean)
1590 Loc : constant Source_Ptr := Sloc (N);
1591 Spec : constant Node_Id := Specification (N);
1592 Designator : Entity_Id;
1594 Null_Body : Node_Id := Empty;
1595 Null_Stmt : Node_Id := Null_Statement (Spec);
1599 -- Capture the profile of the null procedure before analysis, for
1600 -- expansion at the freeze point and at each point of call. The body is
1601 -- used if the procedure has preconditions, or if it is a completion. In
1602 -- the first case the body is analyzed at the freeze point, in the other
1603 -- it replaces the null procedure declaration.
1605 -- For a null procedure that comes from source, a NULL statement is
1606 -- provided by the parser, which carries the source location of the
1607 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1608 -- from expansion, create one now.
1610 if No (Null_Stmt) then
1611 Null_Stmt := Make_Null_Statement (Loc);
1615 Make_Subprogram_Body (Loc,
1616 Specification => New_Copy_Tree (Spec),
1617 Declarations => New_List,
1618 Handled_Statement_Sequence =>
1619 Make_Handled_Sequence_Of_Statements (Loc,
1620 Statements => New_List (Null_Stmt)));
1622 -- Create new entities for body and formals
1624 Set_Defining_Unit_Name (Specification (Null_Body),
1625 Make_Defining_Identifier
1626 (Sloc (Defining_Entity (N)),
1627 Chars (Defining_Entity (N))));
1629 Form := First (Parameter_Specifications (Specification (Null_Body)));
1630 while Present (Form) loop
1631 Set_Defining_Identifier (Form,
1632 Make_Defining_Identifier
1633 (Sloc (Defining_Identifier (Form)),
1634 Chars (Defining_Identifier (Form))));
1638 -- Determine whether the null procedure may be a completion of a generic
1639 -- suprogram, in which case we use the new null body as the completion
1640 -- and set minimal semantic information on the original declaration,
1641 -- which is rewritten as a null statement.
1643 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1645 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1646 Insert_Before (N, Null_Body);
1647 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1649 Rewrite (N, Make_Null_Statement (Loc));
1650 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1651 Is_Completion := True;
1655 -- Resolve the types of the formals now, because the freeze point may
1656 -- appear in a different context, e.g. an instantiation.
1658 Form := First (Parameter_Specifications (Specification (Null_Body)));
1659 while Present (Form) loop
1660 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1661 Find_Type (Parameter_Type (Form));
1663 elsif No (Access_To_Subprogram_Definition
1664 (Parameter_Type (Form)))
1666 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1668 -- The case of a null procedure with a formal that is an
1669 -- access-to-subprogram type, and that is used as an actual
1670 -- in an instantiation is left to the enthusiastic reader.
1680 -- If there are previous overloadable entities with the same name, check
1681 -- whether any of them is completed by the null procedure.
1683 if Present (Prev) and then Is_Overloadable (Prev) then
1684 Designator := Analyze_Subprogram_Specification (Spec);
1685 Prev := Find_Corresponding_Spec (N);
1688 if No (Prev) or else not Comes_From_Source (Prev) then
1689 Designator := Analyze_Subprogram_Specification (Spec);
1690 Set_Has_Completion (Designator);
1692 -- Signal to caller that this is a procedure declaration
1694 Is_Completion := False;
1696 -- Null procedures are always inlined, but generic formal subprograms
1697 -- which appear as such in the internal instance of formal packages,
1698 -- need no completion and are not marked Inline.
1701 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1703 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1704 Set_Body_To_Inline (N, Null_Body);
1705 Set_Is_Inlined (Designator);
1709 -- The null procedure is a completion. We unconditionally rewrite
1710 -- this as a null body (even if expansion is not active), because
1711 -- there are various error checks that are applied on this body
1712 -- when it is analyzed (e.g. correct aspect placement).
1714 if Has_Completion (Prev) then
1715 Error_Msg_Sloc := Sloc (Prev);
1716 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1719 Check_Previous_Null_Procedure (N, Prev);
1721 Is_Completion := True;
1722 Rewrite (N, Null_Body);
1725 end Analyze_Null_Procedure;
1727 -----------------------------
1728 -- Analyze_Operator_Symbol --
1729 -----------------------------
1731 -- An operator symbol such as "+" or "and" may appear in context where the
1732 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1733 -- is just a string, as in (conjunction = "or"). In these cases the parser
1734 -- generates this node, and the semantics does the disambiguation. Other
1735 -- such case are actuals in an instantiation, the generic unit in an
1736 -- instantiation, and pragma arguments.
1738 procedure Analyze_Operator_Symbol (N : Node_Id) is
1739 Par : constant Node_Id := Parent (N);
1742 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1743 or else Nkind (Par) = N_Function_Instantiation
1744 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1745 or else (Nkind (Par) = N_Pragma_Argument_Association
1746 and then not Is_Pragma_String_Literal (Par))
1747 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1748 or else (Nkind (Par) = N_Attribute_Reference
1749 and then Attribute_Name (Par) /= Name_Value)
1751 Find_Direct_Name (N);
1754 Change_Operator_Symbol_To_String_Literal (N);
1757 end Analyze_Operator_Symbol;
1759 -----------------------------------
1760 -- Analyze_Parameter_Association --
1761 -----------------------------------
1763 procedure Analyze_Parameter_Association (N : Node_Id) is
1765 Analyze (Explicit_Actual_Parameter (N));
1766 end Analyze_Parameter_Association;
1768 ----------------------------
1769 -- Analyze_Procedure_Call --
1770 ----------------------------
1772 -- WARNING: This routine manages Ghost regions. Return statements must be
1773 -- replaced by gotos which jump to the end of the routine and restore the
1776 procedure Analyze_Procedure_Call (N : Node_Id) is
1777 procedure Analyze_Call_And_Resolve;
1778 -- Do Analyze and Resolve calls for procedure call. At the end, check
1779 -- for illegal order dependence.
1780 -- ??? where is the check for illegal order dependencies?
1782 ------------------------------
1783 -- Analyze_Call_And_Resolve --
1784 ------------------------------
1786 procedure Analyze_Call_And_Resolve is
1788 if Nkind (N) = N_Procedure_Call_Statement then
1790 Resolve (N, Standard_Void_Type);
1794 end Analyze_Call_And_Resolve;
1798 Actuals : constant List_Id := Parameter_Associations (N);
1799 Loc : constant Source_Ptr := Sloc (N);
1800 P : constant Node_Id := Name (N);
1802 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1803 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
1804 -- Save the Ghost-related attributes to restore on exit
1809 -- Start of processing for Analyze_Procedure_Call
1812 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1813 -- a procedure call or an entry call. The prefix may denote an access
1814 -- to subprogram type, in which case an implicit dereference applies.
1815 -- If the prefix is an indexed component (without implicit dereference)
1816 -- then the construct denotes a call to a member of an entire family.
1817 -- If the prefix is a simple name, it may still denote a call to a
1818 -- parameterless member of an entry family. Resolution of these various
1819 -- interpretations is delicate.
1821 -- Do not analyze machine code statements to avoid rejecting them in
1824 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1825 Set_Etype (P, Standard_Void_Type);
1830 -- If this is a call of the form Obj.Op, the call may have been analyzed
1831 -- and possibly rewritten into a block, in which case we are done.
1833 if Analyzed (N) then
1836 -- If there is an error analyzing the name (which may have been
1837 -- rewritten if the original call was in prefix notation) then error
1838 -- has been emitted already, mark node and return.
1840 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1841 Set_Etype (N, Any_Type);
1845 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1846 -- Set the mode now to ensure that any nodes generated during analysis
1847 -- and expansion are properly marked as Ghost.
1849 Mark_And_Set_Ghost_Procedure_Call (N);
1851 -- Otherwise analyze the parameters
1853 if Present (Actuals) then
1854 Actual := First (Actuals);
1856 while Present (Actual) loop
1858 Check_Parameterless_Call (Actual);
1863 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1865 if Nkind (P) = N_Attribute_Reference
1866 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1868 Name_Elab_Subp_Body)
1870 if Present (Actuals) then
1872 ("no parameters allowed for this call", First (Actuals));
1876 Set_Etype (N, Standard_Void_Type);
1879 elsif Is_Entity_Name (P)
1880 and then Is_Record_Type (Etype (Entity (P)))
1881 and then Remote_AST_I_Dereference (P)
1885 elsif Is_Entity_Name (P)
1886 and then Ekind (Entity (P)) /= E_Entry_Family
1888 if Is_Access_Type (Etype (P))
1889 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1890 and then No (Actuals)
1891 and then Comes_From_Source (N)
1893 Error_Msg_N ("missing explicit dereference in call", N);
1896 Analyze_Call_And_Resolve;
1898 -- If the prefix is the simple name of an entry family, this is a
1899 -- parameterless call from within the task body itself.
1901 elsif Is_Entity_Name (P)
1902 and then Nkind (P) = N_Identifier
1903 and then Ekind (Entity (P)) = E_Entry_Family
1904 and then Present (Actuals)
1905 and then No (Next (First (Actuals)))
1907 -- Can be call to parameterless entry family. What appears to be the
1908 -- sole argument is in fact the entry index. Rewrite prefix of node
1909 -- accordingly. Source representation is unchanged by this
1913 Make_Indexed_Component (Loc,
1915 Make_Selected_Component (Loc,
1916 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1917 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1918 Expressions => Actuals);
1919 Set_Name (N, New_N);
1920 Set_Etype (New_N, Standard_Void_Type);
1921 Set_Parameter_Associations (N, No_List);
1922 Analyze_Call_And_Resolve;
1924 elsif Nkind (P) = N_Explicit_Dereference then
1925 if Ekind (Etype (P)) = E_Subprogram_Type then
1926 Analyze_Call_And_Resolve;
1928 Error_Msg_N ("expect access to procedure in call", P);
1931 -- The name can be a selected component or an indexed component that
1932 -- yields an access to subprogram. Such a prefix is legal if the call
1933 -- has parameter associations.
1935 elsif Is_Access_Type (Etype (P))
1936 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1938 if Present (Actuals) then
1939 Analyze_Call_And_Resolve;
1941 Error_Msg_N ("missing explicit dereference in call ", N);
1944 -- If not an access to subprogram, then the prefix must resolve to the
1945 -- name of an entry, entry family, or protected operation.
1947 -- For the case of a simple entry call, P is a selected component where
1948 -- the prefix is the task and the selector name is the entry. A call to
1949 -- a protected procedure will have the same syntax. If the protected
1950 -- object contains overloaded operations, the entity may appear as a
1951 -- function, the context will select the operation whose type is Void.
1953 elsif Nkind (P) = N_Selected_Component
1954 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1958 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1959 -- in prefix notation may still be missing its controlling argument,
1960 -- so perform the transformation now.
1962 if SPARK_Mode = On and then In_Inlined_Body then
1964 Subp : constant Entity_Id := Entity (Selector_Name (P));
1965 Typ : constant Entity_Id := Etype (Prefix (P));
1968 if Is_Tagged_Type (Typ)
1969 and then Present (First_Formal (Subp))
1970 and then (Etype (First_Formal (Subp)) = Typ
1972 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1973 and then Try_Object_Operation (P)
1978 Analyze_Call_And_Resolve;
1983 Analyze_Call_And_Resolve;
1986 elsif Nkind (P) = N_Selected_Component
1987 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1988 and then Present (Actuals)
1989 and then No (Next (First (Actuals)))
1991 -- Can be call to parameterless entry family. What appears to be the
1992 -- sole argument is in fact the entry index. Rewrite prefix of node
1993 -- accordingly. Source representation is unchanged by this
1997 Make_Indexed_Component (Loc,
1998 Prefix => New_Copy (P),
1999 Expressions => Actuals);
2000 Set_Name (N, New_N);
2001 Set_Etype (New_N, Standard_Void_Type);
2002 Set_Parameter_Associations (N, No_List);
2003 Analyze_Call_And_Resolve;
2005 -- For the case of a reference to an element of an entry family, P is
2006 -- an indexed component whose prefix is a selected component (task and
2007 -- entry family), and whose index is the entry family index.
2009 elsif Nkind (P) = N_Indexed_Component
2010 and then Nkind (Prefix (P)) = N_Selected_Component
2011 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
2013 Analyze_Call_And_Resolve;
2015 -- If the prefix is the name of an entry family, it is a call from
2016 -- within the task body itself.
2018 elsif Nkind (P) = N_Indexed_Component
2019 and then Nkind (Prefix (P)) = N_Identifier
2020 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
2023 Make_Selected_Component (Loc,
2025 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
2026 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
2027 Rewrite (Prefix (P), New_N);
2029 Analyze_Call_And_Resolve;
2031 -- In Ada 2012. a qualified expression is a name, but it cannot be a
2032 -- procedure name, so the construct can only be a qualified expression.
2034 elsif Nkind (P) = N_Qualified_Expression
2035 and then Ada_Version >= Ada_2012
2037 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
2040 -- Anything else is an error
2043 Error_Msg_N ("invalid procedure or entry call", N);
2047 Restore_Ghost_Region (Saved_GM, Saved_IGR);
2048 end Analyze_Procedure_Call;
2050 ------------------------------
2051 -- Analyze_Return_Statement --
2052 ------------------------------
2054 procedure Analyze_Return_Statement (N : Node_Id) is
2055 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2056 N_Simple_Return_Statement));
2058 Returns_Object : constant Boolean :=
2059 Nkind (N) = N_Extended_Return_Statement
2061 (Nkind (N) = N_Simple_Return_Statement
2062 and then Present (Expression (N)));
2063 -- True if we're returning something; that is, "return <expression>;"
2064 -- or "return Result : T [:= ...]". False for "return;". Used for error
2065 -- checking: If Returns_Object is True, N should apply to a function
2066 -- body; otherwise N should apply to a procedure body, entry body,
2067 -- accept statement, or extended return statement.
2069 function Find_What_It_Applies_To return Entity_Id;
2070 -- Find the entity representing the innermost enclosing body, accept
2071 -- statement, or extended return statement. If the result is a callable
2072 -- construct or extended return statement, then this will be the value
2073 -- of the Return_Applies_To attribute. Otherwise, the program is
2074 -- illegal. See RM-6.5(4/2).
2076 -----------------------------
2077 -- Find_What_It_Applies_To --
2078 -----------------------------
2080 function Find_What_It_Applies_To return Entity_Id is
2081 Result : Entity_Id := Empty;
2084 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2085 -- and postconditions.
2087 for J in reverse 0 .. Scope_Stack.Last loop
2088 Result := Scope_Stack.Table (J).Entity;
2089 exit when not Ekind_In (Result, E_Block, E_Loop)
2090 and then Chars (Result) /= Name_uPostconditions;
2093 pragma Assert (Present (Result));
2095 end Find_What_It_Applies_To;
2097 -- Local declarations
2099 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2100 Kind : constant Entity_Kind := Ekind (Scope_Id);
2101 Loc : constant Source_Ptr := Sloc (N);
2102 Stm_Entity : constant Entity_Id :=
2104 (E_Return_Statement, Current_Scope, Loc, 'R');
2106 -- Start of processing for Analyze_Return_Statement
2109 Set_Return_Statement_Entity (N, Stm_Entity);
2111 Set_Etype (Stm_Entity, Standard_Void_Type);
2112 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2114 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2115 -- (4/2): an inner return statement will apply to this extended return.
2117 if Nkind (N) = N_Extended_Return_Statement then
2118 Push_Scope (Stm_Entity);
2121 -- Check that pragma No_Return is obeyed. Don't complain about the
2122 -- implicitly-generated return that is placed at the end.
2124 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2125 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2128 -- Warn on any unassigned OUT parameters if in procedure
2130 if Ekind (Scope_Id) = E_Procedure then
2131 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2134 -- Check that functions return objects, and other things do not
2136 if Kind = E_Function or else Kind = E_Generic_Function then
2137 if not Returns_Object then
2138 Error_Msg_N ("missing expression in return from function", N);
2141 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2142 if Returns_Object then
2143 Error_Msg_N ("procedure cannot return value (use function)", N);
2146 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2147 if Returns_Object then
2148 if Is_Protected_Type (Scope (Scope_Id)) then
2149 Error_Msg_N ("entry body cannot return value", N);
2151 Error_Msg_N ("accept statement cannot return value", N);
2155 elsif Kind = E_Return_Statement then
2157 -- We are nested within another return statement, which must be an
2158 -- extended_return_statement.
2160 if Returns_Object then
2161 if Nkind (N) = N_Extended_Return_Statement then
2163 ("extended return statement cannot be nested (use `RETURN;`)",
2166 -- Case of a simple return statement with a value inside extended
2167 -- return statement.
2171 ("return nested in extended return statement cannot return "
2172 & "value (use `RETURN;`)", N);
2177 Error_Msg_N ("illegal context for return statement", N);
2180 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2181 Analyze_Function_Return (N);
2183 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2184 Set_Return_Present (Scope_Id);
2187 if Nkind (N) = N_Extended_Return_Statement then
2191 Kill_Current_Values (Last_Assignment_Only => True);
2192 Check_Unreachable_Code (N);
2194 Analyze_Dimension (N);
2195 end Analyze_Return_Statement;
2197 -------------------------------------
2198 -- Analyze_Simple_Return_Statement --
2199 -------------------------------------
2201 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2203 if Present (Expression (N)) then
2204 Mark_Coextensions (N, Expression (N));
2207 Analyze_Return_Statement (N);
2208 end Analyze_Simple_Return_Statement;
2210 -------------------------
2211 -- Analyze_Return_Type --
2212 -------------------------
2214 procedure Analyze_Return_Type (N : Node_Id) is
2215 Designator : constant Entity_Id := Defining_Entity (N);
2216 Typ : Entity_Id := Empty;
2219 -- Normal case where result definition does not indicate an error
2221 if Result_Definition (N) /= Error then
2222 if Nkind (Result_Definition (N)) = N_Access_Definition then
2223 Check_SPARK_05_Restriction
2224 ("access result is not allowed", Result_Definition (N));
2226 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2229 AD : constant Node_Id :=
2230 Access_To_Subprogram_Definition (Result_Definition (N));
2232 if Present (AD) and then Protected_Present (AD) then
2233 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2235 Typ := Access_Definition (N, Result_Definition (N));
2239 Set_Parent (Typ, Result_Definition (N));
2240 Set_Is_Local_Anonymous_Access (Typ);
2241 Set_Etype (Designator, Typ);
2243 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2245 Null_Exclusion_Static_Checks (N);
2247 -- Subtype_Mark case
2250 Find_Type (Result_Definition (N));
2251 Typ := Entity (Result_Definition (N));
2252 Set_Etype (Designator, Typ);
2254 -- Unconstrained array as result is not allowed in SPARK
2256 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2257 Check_SPARK_05_Restriction
2258 ("returning an unconstrained array is not allowed",
2259 Result_Definition (N));
2262 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2264 Null_Exclusion_Static_Checks (N);
2266 -- If a null exclusion is imposed on the result type, then create
2267 -- a null-excluding itype (an access subtype) and use it as the
2268 -- function's Etype. Note that the null exclusion checks are done
2269 -- right before this, because they don't get applied to types that
2270 -- do not come from source.
2272 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2273 Set_Etype (Designator,
2274 Create_Null_Excluding_Itype
2277 Scope_Id => Scope (Current_Scope)));
2279 -- The new subtype must be elaborated before use because
2280 -- it is visible outside of the function. However its base
2281 -- type may not be frozen yet, so the reference that will
2282 -- force elaboration must be attached to the freezing of
2285 -- If the return specification appears on a proper body,
2286 -- the subtype will have been created already on the spec.
2288 if Is_Frozen (Typ) then
2289 if Nkind (Parent (N)) = N_Subprogram_Body
2290 and then Nkind (Parent (Parent (N))) = N_Subunit
2294 Build_Itype_Reference (Etype (Designator), Parent (N));
2298 Ensure_Freeze_Node (Typ);
2301 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2303 Set_Itype (IR, Etype (Designator));
2304 Append_Freeze_Actions (Typ, New_List (IR));
2309 Set_Etype (Designator, Typ);
2312 if Ekind (Typ) = E_Incomplete_Type
2313 or else (Is_Class_Wide_Type (Typ)
2314 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2316 -- AI05-0151: Tagged incomplete types are allowed in all formal
2317 -- parts. Untagged incomplete types are not allowed in bodies.
2318 -- As a consequence, limited views cannot appear in a basic
2319 -- declaration that is itself within a body, because there is
2320 -- no point at which the non-limited view will become visible.
2322 if Ada_Version >= Ada_2012 then
2323 if From_Limited_With (Typ) and then In_Package_Body then
2325 ("invalid use of incomplete type&",
2326 Result_Definition (N), Typ);
2328 -- The return type of a subprogram body cannot be of a
2329 -- formal incomplete type.
2331 elsif Is_Generic_Type (Typ)
2332 and then Nkind (Parent (N)) = N_Subprogram_Body
2335 ("return type cannot be a formal incomplete type",
2336 Result_Definition (N));
2338 elsif Is_Class_Wide_Type (Typ)
2339 and then Is_Generic_Type (Root_Type (Typ))
2340 and then Nkind (Parent (N)) = N_Subprogram_Body
2343 ("return type cannot be a formal incomplete type",
2344 Result_Definition (N));
2346 elsif Is_Tagged_Type (Typ) then
2349 -- Use is legal in a thunk generated for an operation
2350 -- inherited from a progenitor.
2352 elsif Is_Thunk (Designator)
2353 and then Present (Non_Limited_View (Typ))
2357 elsif Nkind (Parent (N)) = N_Subprogram_Body
2358 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2362 ("invalid use of untagged incomplete type&",
2366 -- The type must be completed in the current package. This
2367 -- is checked at the end of the package declaration when
2368 -- Taft-amendment types are identified. If the return type
2369 -- is class-wide, there is no required check, the type can
2370 -- be a bona fide TAT.
2372 if Ekind (Scope (Current_Scope)) = E_Package
2373 and then In_Private_Part (Scope (Current_Scope))
2374 and then not Is_Class_Wide_Type (Typ)
2376 Append_Elmt (Designator, Private_Dependents (Typ));
2381 ("invalid use of incomplete type&", Designator, Typ);
2386 -- Case where result definition does indicate an error
2389 Set_Etype (Designator, Any_Type);
2391 end Analyze_Return_Type;
2393 -----------------------------
2394 -- Analyze_Subprogram_Body --
2395 -----------------------------
2397 procedure Analyze_Subprogram_Body (N : Node_Id) is
2398 Loc : constant Source_Ptr := Sloc (N);
2399 Body_Spec : constant Node_Id := Specification (N);
2400 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2403 if Debug_Flag_C then
2404 Write_Str ("==> subprogram body ");
2405 Write_Name (Chars (Body_Id));
2406 Write_Str (" from ");
2407 Write_Location (Loc);
2412 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2414 -- The real work is split out into the helper, so it can do "return;"
2415 -- without skipping the debug output:
2417 Analyze_Subprogram_Body_Helper (N);
2419 if Debug_Flag_C then
2421 Write_Str ("<== subprogram body ");
2422 Write_Name (Chars (Body_Id));
2423 Write_Str (" from ");
2424 Write_Location (Loc);
2427 end Analyze_Subprogram_Body;
2429 ------------------------------------
2430 -- Analyze_Subprogram_Body_Helper --
2431 ------------------------------------
2433 -- This procedure is called for regular subprogram bodies, generic bodies,
2434 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2435 -- specification matters, and is used to create a proper declaration for
2436 -- the subprogram, or to perform conformance checks.
2438 -- WARNING: This routine manages Ghost regions. Return statements must be
2439 -- replaced by gotos which jump to the end of the routine and restore the
2442 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2443 Body_Spec : Node_Id := Specification (N);
2444 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2445 Loc : constant Source_Ptr := Sloc (N);
2446 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2448 Conformant : Boolean;
2449 Desig_View : Entity_Id := Empty;
2450 Exch_Views : Elist_Id := No_Elist;
2452 Mask_Types : Elist_Id := No_Elist;
2453 Prot_Typ : Entity_Id := Empty;
2454 Spec_Decl : Node_Id := Empty;
2455 Spec_Id : Entity_Id;
2457 Last_Real_Spec_Entity : Entity_Id := Empty;
2458 -- When we analyze a separate spec, the entity chain ends up containing
2459 -- the formals, as well as any itypes generated during analysis of the
2460 -- default expressions for parameters, or the arguments of associated
2461 -- precondition/postcondition pragmas (which are analyzed in the context
2462 -- of the spec since they have visibility on formals).
2464 -- These entities belong with the spec and not the body. However we do
2465 -- the analysis of the body in the context of the spec (again to obtain
2466 -- visibility to the formals), and all the entities generated during
2467 -- this analysis end up also chained to the entity chain of the spec.
2468 -- But they really belong to the body, and there is circuitry to move
2469 -- them from the spec to the body.
2471 -- However, when we do this move, we don't want to move the real spec
2472 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2473 -- variable points to the last real spec entity, so we only move those
2474 -- chained beyond that point. It is initialized to Empty to deal with
2475 -- the case where there is no separate spec.
2477 function Body_Has_Contract return Boolean;
2478 -- Check whether unanalyzed body has an aspect or pragma that may
2479 -- generate a SPARK contract.
2481 function Body_Has_SPARK_Mode_On return Boolean;
2482 -- Check whether SPARK_Mode On applies to the subprogram body, either
2483 -- because it is specified directly on the body, or because it is
2484 -- inherited from the enclosing subprogram or package.
2486 procedure Build_Subprogram_Declaration;
2487 -- Create a matching subprogram declaration for subprogram body N
2489 procedure Check_Anonymous_Return;
2490 -- Ada 2005: if a function returns an access type that denotes a task,
2491 -- or a type that contains tasks, we must create a master entity for
2492 -- the anonymous type, which typically will be used in an allocator
2493 -- in the body of the function.
2495 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2496 -- Look ahead to recognize a pragma that may appear after the body.
2497 -- If there is a previous spec, check that it appears in the same
2498 -- declarative part. If the pragma is Inline_Always, perform inlining
2499 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2500 -- If the body acts as a spec, and inlining is required, we create a
2501 -- subprogram declaration for it, in order to attach the body to inline.
2502 -- If pragma does not appear after the body, check whether there is
2503 -- an inline pragma before any local declarations.
2505 procedure Check_Missing_Return;
2506 -- Checks for a function with a no return statements, and also performs
2507 -- the warning checks implemented by Check_Returns. In formal mode, also
2508 -- verify that a function ends with a RETURN and that a procedure does
2509 -- not contain any RETURN.
2511 function Disambiguate_Spec return Entity_Id;
2512 -- When a primitive is declared between the private view and the full
2513 -- view of a concurrent type which implements an interface, a special
2514 -- mechanism is used to find the corresponding spec of the primitive
2517 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2518 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2519 -- incomplete types coming from a limited context and replace their
2520 -- limited views with the non-limited ones. Return the list of changes
2521 -- to be used to undo the transformation.
2523 function Is_Private_Concurrent_Primitive
2524 (Subp_Id : Entity_Id) return Boolean;
2525 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2526 -- type that implements an interface and has a private view.
2528 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2529 -- N is the body generated for an expression function that is not a
2530 -- completion and Spec_Id the defining entity of its spec. Mark all
2531 -- the not-yet-frozen types referenced by the simple return statement
2532 -- of the function as formally frozen.
2534 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2535 -- Undo the transformation done by Exchange_Limited_Views.
2537 procedure Set_Trivial_Subprogram (N : Node_Id);
2538 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2539 -- subprogram whose body is being analyzed. N is the statement node
2540 -- causing the flag to be set, if the following statement is a return
2541 -- of an entity, we mark the entity as set in source to suppress any
2542 -- warning on the stylized use of function stubs with a dummy return.
2544 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2545 -- Undo the transformation done by Mask_Unfrozen_Types
2547 procedure Verify_Overriding_Indicator;
2548 -- If there was a previous spec, the entity has been entered in the
2549 -- current scope previously. If the body itself carries an overriding
2550 -- indicator, check that it is consistent with the known status of the
2553 -----------------------
2554 -- Body_Has_Contract --
2555 -----------------------
2557 function Body_Has_Contract return Boolean is
2558 Decls : constant List_Id := Declarations (N);
2562 -- Check for aspects that may generate a contract
2564 if Present (Aspect_Specifications (N)) then
2565 Item := First (Aspect_Specifications (N));
2566 while Present (Item) loop
2567 if Is_Subprogram_Contract_Annotation (Item) then
2575 -- Check for pragmas that may generate a contract
2577 if Present (Decls) then
2578 Item := First (Decls);
2579 while Present (Item) loop
2580 if Nkind (Item) = N_Pragma
2581 and then Is_Subprogram_Contract_Annotation (Item)
2591 end Body_Has_Contract;
2593 ----------------------------
2594 -- Body_Has_SPARK_Mode_On --
2595 ----------------------------
2597 function Body_Has_SPARK_Mode_On return Boolean is
2598 Decls : constant List_Id := Declarations (N);
2602 -- Check for SPARK_Mode aspect
2604 if Present (Aspect_Specifications (N)) then
2605 Item := First (Aspect_Specifications (N));
2606 while Present (Item) loop
2607 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2608 return Get_SPARK_Mode_From_Annotation (Item) = On;
2615 -- Check for SPARK_Mode pragma
2617 if Present (Decls) then
2618 Item := First (Decls);
2619 while Present (Item) loop
2621 -- Pragmas that apply to a subprogram body are usually grouped
2622 -- together. Look for a potential pragma SPARK_Mode among them.
2624 if Nkind (Item) = N_Pragma then
2625 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2626 return Get_SPARK_Mode_From_Annotation (Item) = On;
2629 -- Otherwise the first non-pragma declarative item terminates
2630 -- the region where pragma SPARK_Mode may appear.
2640 -- Otherwise, the applicable SPARK_Mode is inherited from the
2641 -- enclosing subprogram or package.
2643 return SPARK_Mode = On;
2644 end Body_Has_SPARK_Mode_On;
2646 ----------------------------------
2647 -- Build_Subprogram_Declaration --
2648 ----------------------------------
2650 procedure Build_Subprogram_Declaration is
2651 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2652 -- Relocate certain categorization pragmas from the declarative list
2653 -- of subprogram body From and insert them after node To. The pragmas
2656 -- Volatile_Function
2657 -- Also copy pragma SPARK_Mode if present in the declarative list
2658 -- of subprogram body From and insert it after node To. This pragma
2659 -- should not be moved, as it applies to the body too.
2665 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2667 Next_Decl : Node_Id;
2670 pragma Assert (Nkind (From) = N_Subprogram_Body);
2672 -- The destination node must be part of a list, as the pragmas are
2673 -- inserted after it.
2675 pragma Assert (Is_List_Member (To));
2677 -- Inspect the declarations of the subprogram body looking for
2678 -- specific pragmas.
2680 Decl := First (Declarations (N));
2681 while Present (Decl) loop
2682 Next_Decl := Next (Decl);
2684 if Nkind (Decl) = N_Pragma then
2685 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2686 Insert_After (To, New_Copy_Tree (Decl));
2688 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2690 Name_Volatile_Function)
2693 Insert_After (To, Decl);
2704 Subp_Decl : Node_Id;
2706 -- Start of processing for Build_Subprogram_Declaration
2709 -- Create a matching subprogram spec using the profile of the body.
2710 -- The structure of the tree is identical, but has new entities for
2711 -- the defining unit name and formal parameters.
2714 Make_Subprogram_Declaration (Loc,
2715 Specification => Copy_Subprogram_Spec (Body_Spec));
2716 Set_Comes_From_Source (Subp_Decl, True);
2718 -- Relocate the aspects and relevant pragmas from the subprogram body
2719 -- to the generated spec because it acts as the initial declaration.
2721 Insert_Before (N, Subp_Decl);
2722 Move_Aspects (N, To => Subp_Decl);
2723 Move_Pragmas (N, To => Subp_Decl);
2725 -- Ensure that the generated corresponding spec and original body
2726 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2727 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2728 -- correctly set for local subprograms.
2730 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2732 Analyze (Subp_Decl);
2734 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2735 -- the body since the expander may generate calls using that entity.
2736 -- Required to ensure that Expand_Call rewrites calls to this
2737 -- function by calls to the built procedure.
2739 if Modify_Tree_For_C
2740 and then Nkind (Body_Spec) = N_Function_Specification
2742 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2744 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2745 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2746 Corresponding_Procedure
2747 (Defining_Entity (Specification (Subp_Decl))));
2750 -- Analyze any relocated source pragmas or pragmas created for aspect
2753 Decl := Next (Subp_Decl);
2754 while Present (Decl) loop
2756 -- Stop the search for pragmas once the body has been reached as
2757 -- this terminates the region where pragmas may appear.
2762 elsif Nkind (Decl) = N_Pragma then
2769 Spec_Id := Defining_Entity (Subp_Decl);
2770 Set_Corresponding_Spec (N, Spec_Id);
2772 -- Mark the generated spec as a source construct to ensure that all
2773 -- calls to it are properly registered in ALI files for GNATprove.
2775 Set_Comes_From_Source (Spec_Id, True);
2777 -- Ensure that the specs of the subprogram declaration and its body
2778 -- are identical, otherwise they will appear non-conformant due to
2779 -- rewritings in the default values of formal parameters.
2781 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2782 Set_Specification (N, Body_Spec);
2783 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2784 end Build_Subprogram_Declaration;
2786 ----------------------------
2787 -- Check_Anonymous_Return --
2788 ----------------------------
2790 procedure Check_Anonymous_Return is
2796 if Present (Spec_Id) then
2802 if Ekind (Scop) = E_Function
2803 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2804 and then not Is_Thunk (Scop)
2806 -- Skip internally built functions which handle the case of
2807 -- a null access (see Expand_Interface_Conversion)
2809 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2810 and then not Comes_From_Source (Parent (Scop)))
2812 and then (Has_Task (Designated_Type (Etype (Scop)))
2814 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2816 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2817 and then Expander_Active
2819 -- Avoid cases with no tasking support
2821 and then RTE_Available (RE_Current_Master)
2822 and then not Restriction_Active (No_Task_Hierarchy)
2825 Make_Object_Declaration (Loc,
2826 Defining_Identifier =>
2827 Make_Defining_Identifier (Loc, Name_uMaster),
2828 Constant_Present => True,
2829 Object_Definition =>
2830 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2832 Make_Explicit_Dereference (Loc,
2833 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2835 if Present (Declarations (N)) then
2836 Prepend (Decl, Declarations (N));
2838 Set_Declarations (N, New_List (Decl));
2841 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2842 Set_Has_Master_Entity (Scop);
2844 -- Now mark the containing scope as a task master
2847 while Nkind (Par) /= N_Compilation_Unit loop
2848 Par := Parent (Par);
2849 pragma Assert (Present (Par));
2851 -- If we fall off the top, we are at the outer level, and
2852 -- the environment task is our effective master, so nothing
2856 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2858 Set_Is_Task_Master (Par, True);
2863 end Check_Anonymous_Return;
2865 -------------------------
2866 -- Check_Inline_Pragma --
2867 -------------------------
2869 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2873 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2874 -- True when N is a pragma Inline or Inline_Always that applies
2875 -- to this subprogram.
2877 -----------------------
2878 -- Is_Inline_Pragma --
2879 -----------------------
2881 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2883 if Nkind (N) = N_Pragma
2885 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2886 or else (Pragma_Name_Unmapped (N) = Name_Inline
2888 (Front_End_Inlining or else Optimization_Level > 0)))
2889 and then Present (Pragma_Argument_Associations (N))
2892 Pragma_Arg : Node_Id :=
2893 Expression (First (Pragma_Argument_Associations (N)));
2895 if Nkind (Pragma_Arg) = N_Selected_Component then
2896 Pragma_Arg := Selector_Name (Pragma_Arg);
2899 return Chars (Pragma_Arg) = Chars (Body_Id);
2905 end Is_Inline_Pragma;
2907 -- Start of processing for Check_Inline_Pragma
2910 if not Expander_Active then
2914 if Is_List_Member (N)
2915 and then Present (Next (N))
2916 and then Is_Inline_Pragma (Next (N))
2920 elsif Nkind (N) /= N_Subprogram_Body_Stub
2921 and then Present (Declarations (N))
2922 and then Is_Inline_Pragma (First (Declarations (N)))
2924 Prag := First (Declarations (N));
2930 if Present (Prag) then
2931 if Present (Spec_Id) then
2932 if Is_List_Member (N)
2933 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2934 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2940 -- Create a subprogram declaration, to make treatment uniform.
2941 -- Make the sloc of the subprogram name that of the entity in
2942 -- the body, so that style checks find identical strings.
2945 Subp : constant Entity_Id :=
2946 Make_Defining_Identifier
2947 (Sloc (Body_Id), Chars (Body_Id));
2948 Decl : constant Node_Id :=
2949 Make_Subprogram_Declaration (Loc,
2951 New_Copy_Tree (Specification (N)));
2954 -- Link the body and the generated spec
2956 Set_Corresponding_Body (Decl, Body_Id);
2957 Set_Corresponding_Spec (N, Subp);
2959 Set_Defining_Unit_Name (Specification (Decl), Subp);
2961 -- To ensure proper coverage when body is inlined, indicate
2962 -- whether the subprogram comes from source.
2964 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2966 if Present (First_Formal (Body_Id)) then
2967 Plist := Copy_Parameter_List (Body_Id);
2968 Set_Parameter_Specifications
2969 (Specification (Decl), Plist);
2972 -- Move aspects to the new spec
2974 if Has_Aspects (N) then
2975 Move_Aspects (N, To => Decl);
2978 Insert_Before (N, Decl);
2981 Set_Has_Pragma_Inline (Subp);
2983 if Pragma_Name (Prag) = Name_Inline_Always then
2984 Set_Is_Inlined (Subp);
2985 Set_Has_Pragma_Inline_Always (Subp);
2988 -- Prior to copying the subprogram body to create a template
2989 -- for it for subsequent inlining, remove the pragma from
2990 -- the current body so that the copy that will produce the
2991 -- new body will start from a completely unanalyzed tree.
2993 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2994 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
3001 end Check_Inline_Pragma;
3003 --------------------------
3004 -- Check_Missing_Return --
3005 --------------------------
3007 procedure Check_Missing_Return is
3009 Missing_Ret : Boolean;
3012 if Nkind (Body_Spec) = N_Function_Specification then
3013 if Present (Spec_Id) then
3019 if Return_Present (Id) then
3020 Check_Returns (HSS, 'F', Missing_Ret);
3023 Set_Has_Missing_Return (Id);
3026 -- Within a premature instantiation of a package with no body, we
3027 -- build completions of the functions therein, with a Raise
3028 -- statement. No point in complaining about a missing return in
3031 elsif Ekind (Id) = E_Function
3032 and then In_Instance
3033 and then Present (Statements (HSS))
3034 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3038 elsif Is_Generic_Subprogram (Id)
3039 or else not Is_Machine_Code_Subprogram (Id)
3041 Error_Msg_N ("missing RETURN statement in function body", N);
3044 -- If procedure with No_Return, check returns
3046 elsif Nkind (Body_Spec) = N_Procedure_Specification
3047 and then Present (Spec_Id)
3048 and then No_Return (Spec_Id)
3050 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
3053 -- Special checks in SPARK mode
3055 if Nkind (Body_Spec) = N_Function_Specification then
3057 -- In SPARK mode, last statement of a function should be a return
3060 Stat : constant Node_Id := Last_Source_Statement (HSS);
3063 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3064 N_Extended_Return_Statement)
3066 Check_SPARK_05_Restriction
3067 ("last statement in function should be RETURN", Stat);
3071 -- In SPARK mode, verify that a procedure has no return
3073 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3074 if Present (Spec_Id) then
3080 -- Would be nice to point to return statement here, can we
3081 -- borrow the Check_Returns procedure here ???
3083 if Return_Present (Id) then
3084 Check_SPARK_05_Restriction
3085 ("procedure should not have RETURN", N);
3088 end Check_Missing_Return;
3090 -----------------------
3091 -- Disambiguate_Spec --
3092 -----------------------
3094 function Disambiguate_Spec return Entity_Id is
3095 Priv_Spec : Entity_Id;
3098 procedure Replace_Types (To_Corresponding : Boolean);
3099 -- Depending on the flag, replace the type of formal parameters of
3100 -- Body_Id if it is a concurrent type implementing interfaces with
3101 -- the corresponding record type or the other way around.
3103 procedure Replace_Types (To_Corresponding : Boolean) is
3105 Formal_Typ : Entity_Id;
3108 Formal := First_Formal (Body_Id);
3109 while Present (Formal) loop
3110 Formal_Typ := Etype (Formal);
3112 if Is_Class_Wide_Type (Formal_Typ) then
3113 Formal_Typ := Root_Type (Formal_Typ);
3116 -- From concurrent type to corresponding record
3118 if To_Corresponding then
3119 if Is_Concurrent_Type (Formal_Typ)
3120 and then Present (Corresponding_Record_Type (Formal_Typ))
3123 (Corresponding_Record_Type (Formal_Typ)))
3126 Corresponding_Record_Type (Formal_Typ));
3129 -- From corresponding record to concurrent type
3132 if Is_Concurrent_Record_Type (Formal_Typ)
3133 and then Present (Interfaces (Formal_Typ))
3136 Corresponding_Concurrent_Type (Formal_Typ));
3140 Next_Formal (Formal);
3144 -- Start of processing for Disambiguate_Spec
3147 -- Try to retrieve the specification of the body as is. All error
3148 -- messages are suppressed because the body may not have a spec in
3149 -- its current state.
3151 Spec_N := Find_Corresponding_Spec (N, False);
3153 -- It is possible that this is the body of a primitive declared
3154 -- between a private and a full view of a concurrent type. The
3155 -- controlling parameter of the spec carries the concurrent type,
3156 -- not the corresponding record type as transformed by Analyze_
3157 -- Subprogram_Specification. In such cases, we undo the change
3158 -- made by the analysis of the specification and try to find the
3161 -- Note that wrappers already have their corresponding specs and
3162 -- bodies set during their creation, so if the candidate spec is
3163 -- a wrapper, then we definitely need to swap all types to their
3164 -- original concurrent status.
3167 or else Is_Primitive_Wrapper (Spec_N)
3169 -- Restore all references of corresponding record types to the
3170 -- original concurrent types.
3172 Replace_Types (To_Corresponding => False);
3173 Priv_Spec := Find_Corresponding_Spec (N, False);
3175 -- The current body truly belongs to a primitive declared between
3176 -- a private and a full view. We leave the modified body as is,
3177 -- and return the true spec.
3179 if Present (Priv_Spec)
3180 and then Is_Private_Primitive (Priv_Spec)
3185 -- In case that this is some sort of error, restore the original
3186 -- state of the body.
3188 Replace_Types (To_Corresponding => True);
3192 end Disambiguate_Spec;
3194 ----------------------------
3195 -- Exchange_Limited_Views --
3196 ----------------------------
3198 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3199 Result : Elist_Id := No_Elist;
3201 procedure Detect_And_Exchange (Id : Entity_Id);
3202 -- Determine whether Id's type denotes an incomplete type associated
3203 -- with a limited with clause and exchange the limited view with the
3204 -- non-limited one when available. Note that the non-limited view
3205 -- may exist because of a with_clause in another unit in the context,
3206 -- but cannot be used because the current view of the enclosing unit
3207 -- is still a limited view.
3209 -------------------------
3210 -- Detect_And_Exchange --
3211 -------------------------
3213 procedure Detect_And_Exchange (Id : Entity_Id) is
3214 Typ : constant Entity_Id := Etype (Id);
3216 if From_Limited_With (Typ)
3217 and then Has_Non_Limited_View (Typ)
3218 and then not From_Limited_With (Scope (Typ))
3221 Result := New_Elmt_List;
3224 Prepend_Elmt (Typ, Result);
3225 Prepend_Elmt (Id, Result);
3226 Set_Etype (Id, Non_Limited_View (Typ));
3228 end Detect_And_Exchange;
3234 -- Start of processing for Exchange_Limited_Views
3237 -- Do not process subprogram bodies as they already use the non-
3238 -- limited view of types.
3240 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3244 -- Examine all formals and swap views when applicable
3246 Formal := First_Formal (Subp_Id);
3247 while Present (Formal) loop
3248 Detect_And_Exchange (Formal);
3250 Next_Formal (Formal);
3253 -- Process the return type of a function
3255 if Ekind (Subp_Id) = E_Function then
3256 Detect_And_Exchange (Subp_Id);
3260 end Exchange_Limited_Views;
3262 -------------------------------------
3263 -- Is_Private_Concurrent_Primitive --
3264 -------------------------------------
3266 function Is_Private_Concurrent_Primitive
3267 (Subp_Id : Entity_Id) return Boolean
3269 Formal_Typ : Entity_Id;
3272 if Present (First_Formal (Subp_Id)) then
3273 Formal_Typ := Etype (First_Formal (Subp_Id));
3275 if Is_Concurrent_Record_Type (Formal_Typ) then
3276 if Is_Class_Wide_Type (Formal_Typ) then
3277 Formal_Typ := Root_Type (Formal_Typ);
3280 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3283 -- The type of the first formal is a concurrent tagged type with
3287 Is_Concurrent_Type (Formal_Typ)
3288 and then Is_Tagged_Type (Formal_Typ)
3289 and then Has_Private_Declaration (Formal_Typ);
3293 end Is_Private_Concurrent_Primitive;
3295 -------------------------
3296 -- Mask_Unfrozen_Types --
3297 -------------------------
3299 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3300 Result : Elist_Id := No_Elist;
3302 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3303 -- Mask all types referenced in the subtree rooted at Node
3305 --------------------
3306 -- Mask_Type_Refs --
3307 --------------------
3309 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3310 procedure Mask_Type (Typ : Entity_Id);
3311 -- ??? what does this do?
3317 procedure Mask_Type (Typ : Entity_Id) is
3319 -- Skip Itypes created by the preanalysis
3322 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3327 if not Is_Frozen (Typ) then
3328 Set_Is_Frozen (Typ);
3329 Append_New_Elmt (Typ, Result);
3333 -- Start of processing for Mask_Type_Refs
3336 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3337 Mask_Type (Etype (Entity (Node)));
3339 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3340 Mask_Type (Scope (Entity (Node)));
3343 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3344 and then Present (Etype (Node))
3346 Mask_Type (Etype (Node));
3352 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3356 Return_Stmt : constant Node_Id :=
3357 First (Statements (Handled_Statement_Sequence (N)));
3359 -- Start of processing for Mask_Unfrozen_Types
3362 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3364 Mask_References (Expression (Return_Stmt));
3367 end Mask_Unfrozen_Types;
3369 ---------------------------
3370 -- Restore_Limited_Views --
3371 ---------------------------
3373 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3374 Elmt : Elmt_Id := First_Elmt (Restore_List);
3378 while Present (Elmt) loop
3381 Set_Etype (Id, Node (Elmt));
3384 end Restore_Limited_Views;
3386 ----------------------------
3387 -- Set_Trivial_Subprogram --
3388 ----------------------------
3390 procedure Set_Trivial_Subprogram (N : Node_Id) is
3391 Nxt : constant Node_Id := Next (N);
3394 Set_Is_Trivial_Subprogram (Body_Id);
3396 if Present (Spec_Id) then
3397 Set_Is_Trivial_Subprogram (Spec_Id);
3401 and then Nkind (Nxt) = N_Simple_Return_Statement
3402 and then No (Next (Nxt))
3403 and then Present (Expression (Nxt))
3404 and then Is_Entity_Name (Expression (Nxt))
3406 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3408 end Set_Trivial_Subprogram;
3410 ---------------------------
3411 -- Unmask_Unfrozen_Types --
3412 ---------------------------
3414 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3415 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3418 while Present (Elmt) loop
3419 Set_Is_Frozen (Node (Elmt), False);
3422 end Unmask_Unfrozen_Types;
3424 ---------------------------------
3425 -- Verify_Overriding_Indicator --
3426 ---------------------------------
3428 procedure Verify_Overriding_Indicator is
3430 if Must_Override (Body_Spec) then
3431 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3432 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3436 elsif not Present (Overridden_Operation (Spec_Id)) then
3438 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3440 -- Overriding indicators aren't allowed for protected subprogram
3441 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3442 -- this to a warning if -gnatd.E is enabled.
3444 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3445 Error_Msg_Warn := Error_To_Warning;
3447 ("<<overriding indicator not allowed for protected "
3448 & "subprogram body", Body_Spec);
3451 elsif Must_Not_Override (Body_Spec) then
3452 if Present (Overridden_Operation (Spec_Id)) then
3454 ("subprogram& overrides inherited operation",
3455 Body_Spec, Spec_Id);
3457 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3458 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3461 ("subprogram& overrides predefined operator ",
3462 Body_Spec, Spec_Id);
3464 -- Overriding indicators aren't allowed for protected subprogram
3465 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3466 -- this to a warning if -gnatd.E is enabled.
3468 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3469 Error_Msg_Warn := Error_To_Warning;
3472 ("<<overriding indicator not allowed "
3473 & "for protected subprogram body", Body_Spec);
3475 -- If this is not a primitive operation, then the overriding
3476 -- indicator is altogether illegal.
3478 elsif not Is_Primitive (Spec_Id) then
3480 ("overriding indicator only allowed "
3481 & "if subprogram is primitive", Body_Spec);
3484 -- If checking the style rule and the operation overrides, then
3485 -- issue a warning about a missing overriding_indicator. Protected
3486 -- subprogram bodies are excluded from this style checking, since
3487 -- they aren't primitives (even though their declarations can
3488 -- override) and aren't allowed to have an overriding_indicator.
3491 and then Present (Overridden_Operation (Spec_Id))
3492 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3494 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3495 Style.Missing_Overriding (N, Body_Id);
3498 and then Can_Override_Operator (Spec_Id)
3499 and then not In_Predefined_Unit (Spec_Id)
3501 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3502 Style.Missing_Overriding (N, Body_Id);
3504 end Verify_Overriding_Indicator;
3508 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3509 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
3510 Saved_ISMP : constant Boolean :=
3511 Ignore_SPARK_Mode_Pragmas_In_Instance;
3512 -- Save the Ghost and SPARK mode-related data to restore on exit
3514 -- Start of processing for Analyze_Subprogram_Body_Helper
3517 -- A [generic] subprogram body freezes the contract of the nearest
3518 -- enclosing package body and all other contracts encountered in the
3519 -- same declarative part up to and excluding the subprogram body:
3521 -- package body Nearest_Enclosing_Package
3522 -- with Refined_State => (State => Constit)
3526 -- procedure Freezes_Enclosing_Package_Body
3527 -- with Refined_Depends => (Input => Constit) ...
3529 -- This ensures that any annotations referenced by the contract of the
3530 -- [generic] subprogram body are available. This form of freezing is
3531 -- decoupled from the usual Freeze_xxx mechanism because it must also
3532 -- work in the context of generics where normal freezing is disabled.
3534 -- Only bodies coming from source should cause this type of freezing.
3535 -- Expression functions that act as bodies and complete an initial
3536 -- declaration must be included in this category, hence the use of
3539 if Comes_From_Source (Original_Node (N)) then
3540 Freeze_Previous_Contracts (N);
3543 -- Generic subprograms are handled separately. They always have a
3544 -- generic specification. Determine whether current scope has a
3545 -- previous declaration.
3547 -- If the subprogram body is defined within an instance of the same
3548 -- name, the instance appears as a package renaming, and will be hidden
3549 -- within the subprogram.
3551 if Present (Prev_Id)
3552 and then not Is_Overloadable (Prev_Id)
3553 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3554 or else Comes_From_Source (Prev_Id))
3556 if Is_Generic_Subprogram (Prev_Id) then
3559 -- A subprogram body is Ghost when it is stand alone and subject
3560 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3561 -- the mode now to ensure that any nodes generated during analysis
3562 -- and expansion are properly marked as Ghost.
3564 Mark_And_Set_Ghost_Body (N, Spec_Id);
3566 -- If the body completes the initial declaration of a compilation
3567 -- unit which is subject to pragma Elaboration_Checks, set the
3568 -- model specified by the pragma because it applies to all parts
3571 Install_Elaboration_Model (Spec_Id);
3573 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3574 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3576 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3578 if Nkind (N) = N_Subprogram_Body then
3579 HSS := Handled_Statement_Sequence (N);
3580 Check_Missing_Return;
3585 -- Otherwise a previous entity conflicts with the subprogram name.
3586 -- Attempting to enter name will post error.
3589 Enter_Name (Body_Id);
3593 -- Non-generic case, find the subprogram declaration, if one was seen,
3594 -- or enter new overloaded entity in the current scope. If the
3595 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3596 -- part of the context of one of its subunits. No need to redo the
3599 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3603 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3605 if Nkind (N) = N_Subprogram_Body_Stub
3606 or else No (Corresponding_Spec (N))
3608 if Is_Private_Concurrent_Primitive (Body_Id) then
3609 Spec_Id := Disambiguate_Spec;
3611 -- A subprogram body is Ghost when it is stand alone and
3612 -- subject to pragma Ghost or when the corresponding spec is
3613 -- Ghost. Set the mode now to ensure that any nodes generated
3614 -- during analysis and expansion are properly marked as Ghost.
3616 Mark_And_Set_Ghost_Body (N, Spec_Id);
3618 -- If the body completes a compilation unit which is subject
3619 -- to pragma Elaboration_Checks, set the model specified by
3620 -- the pragma because it applies to all parts of the unit.
3622 Install_Elaboration_Model (Spec_Id);
3625 Spec_Id := Find_Corresponding_Spec (N);
3627 -- A subprogram body is Ghost when it is stand alone and
3628 -- subject to pragma Ghost or when the corresponding spec is
3629 -- Ghost. Set the mode now to ensure that any nodes generated
3630 -- during analysis and expansion are properly marked as Ghost.
3632 Mark_And_Set_Ghost_Body (N, Spec_Id);
3634 -- If the body completes a compilation unit which is subject
3635 -- to pragma Elaboration_Checks, set the model specified by
3636 -- the pragma because it applies to all parts of the unit.
3638 Install_Elaboration_Model (Spec_Id);
3640 -- In GNATprove mode, if the body has no previous spec, create
3641 -- one so that the inlining machinery can operate properly.
3642 -- Transfer aspects, if any, to the new spec, so that they
3643 -- are legal and can be processed ahead of the body.
3644 -- We make two copies of the given spec, one for the new
3645 -- declaration, and one for the body.
3647 if No (Spec_Id) and then GNATprove_Mode
3649 -- Inlining does not apply during pre-analysis of code
3651 and then Full_Analysis
3653 -- Inlining only applies to full bodies, not stubs
3655 and then Nkind (N) /= N_Subprogram_Body_Stub
3657 -- Inlining only applies to bodies in the source code, not to
3658 -- those generated by the compiler. In particular, expression
3659 -- functions, whose body is generated by the compiler, are
3660 -- treated specially by GNATprove.
3662 and then Comes_From_Source (Body_Id)
3664 -- This cannot be done for a compilation unit, which is not
3665 -- in a context where we can insert a new spec.
3667 and then Is_List_Member (N)
3669 -- Inlining only applies to subprograms without contracts,
3670 -- as a contract is a sign that GNATprove should perform a
3671 -- modular analysis of the subprogram instead of a contextual
3672 -- analysis at each call site. The same test is performed in
3673 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3674 -- here in another form (because the contract has not been
3675 -- attached to the body) to avoid front-end errors in case
3676 -- pragmas are used instead of aspects, because the
3677 -- corresponding pragmas in the body would not be transferred
3678 -- to the spec, leading to legality errors.
3680 and then not Body_Has_Contract
3681 and then not Inside_A_Generic
3683 Build_Subprogram_Declaration;
3685 -- If this is a function that returns a constrained array, and
3686 -- we are generating SPARK_For_C, create subprogram declaration
3687 -- to simplify subsequent C generation.
3690 and then Modify_Tree_For_C
3691 and then Nkind (Body_Spec) = N_Function_Specification
3692 and then Is_Array_Type (Etype (Body_Id))
3693 and then Is_Constrained (Etype (Body_Id))
3695 Build_Subprogram_Declaration;
3699 -- If this is a duplicate body, no point in analyzing it
3701 if Error_Posted (N) then
3705 -- A subprogram body should cause freezing of its own declaration,
3706 -- but if there was no previous explicit declaration, then the
3707 -- subprogram will get frozen too late (there may be code within
3708 -- the body that depends on the subprogram having been frozen,
3709 -- such as uses of extra formals), so we force it to be frozen
3710 -- here. Same holds if the body and spec are compilation units.
3711 -- Finally, if the return type is an anonymous access to protected
3712 -- subprogram, it must be frozen before the body because its
3713 -- expansion has generated an equivalent type that is used when
3714 -- elaborating the body.
3716 -- An exception in the case of Ada 2012, AI05-177: The bodies
3717 -- created for expression functions do not freeze.
3720 and then Nkind (Original_Node (N)) /= N_Expression_Function
3722 Freeze_Before (N, Body_Id);
3724 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3725 Freeze_Before (N, Spec_Id);
3727 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3728 Freeze_Before (N, Etype (Body_Id));
3732 Spec_Id := Corresponding_Spec (N);
3734 -- A subprogram body is Ghost when it is stand alone and subject
3735 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3736 -- the mode now to ensure that any nodes generated during analysis
3737 -- and expansion are properly marked as Ghost.
3739 Mark_And_Set_Ghost_Body (N, Spec_Id);
3741 -- If the body completes the initial declaration of a compilation
3742 -- unit which is subject to pragma Elaboration_Checks, set the
3743 -- model specified by the pragma because it applies to all parts
3746 Install_Elaboration_Model (Spec_Id);
3750 -- Previously we scanned the body to look for nested subprograms, and
3751 -- rejected an inline directive if nested subprograms were present,
3752 -- because the back-end would generate conflicting symbols for the
3753 -- nested bodies. This is now unnecessary.
3755 -- Look ahead to recognize a pragma Inline that appears after the body
3757 Check_Inline_Pragma (Spec_Id);
3759 -- Deal with special case of a fully private operation in the body of
3760 -- the protected type. We must create a declaration for the subprogram,
3761 -- in order to attach the protected subprogram that will be used in
3762 -- internal calls. We exclude compiler generated bodies from the
3763 -- expander since the issue does not arise for those cases.
3766 and then Comes_From_Source (N)
3767 and then Is_Protected_Type (Current_Scope)
3769 Spec_Id := Build_Private_Protected_Declaration (N);
3772 -- If we are generating C and this is a function returning a constrained
3773 -- array type for which we must create a procedure with an extra out
3774 -- parameter, build and analyze the body now. The procedure declaration
3775 -- has already been created. We reuse the source body of the function,
3776 -- because in an instance it may contain global references that cannot
3777 -- be reanalyzed. The source function itself is not used any further,
3778 -- so we mark it as having a completion. If the subprogram is a stub the
3779 -- transformation is done later, when the proper body is analyzed.
3782 and then Modify_Tree_For_C
3783 and then Present (Spec_Id)
3784 and then Ekind (Spec_Id) = E_Function
3785 and then Nkind (N) /= N_Subprogram_Body_Stub
3786 and then Rewritten_For_C (Spec_Id)
3788 Set_Has_Completion (Spec_Id);
3790 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3793 -- The entity for the created procedure must remain invisible, so it
3794 -- does not participate in resolution of subsequent references to the
3797 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3801 -- If a separate spec is present, then deal with freezing issues
3803 if Present (Spec_Id) then
3804 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3805 Verify_Overriding_Indicator;
3807 -- In general, the spec will be frozen when we start analyzing the
3808 -- body. However, for internally generated operations, such as
3809 -- wrapper functions for inherited operations with controlling
3810 -- results, the spec may not have been frozen by the time we expand
3811 -- the freeze actions that include the bodies. In particular, extra
3812 -- formals for accessibility or for return-in-place may need to be
3813 -- generated. Freeze nodes, if any, are inserted before the current
3814 -- body. These freeze actions are also needed in ASIS mode and in
3815 -- Compile_Only mode to enable the proper back-end type annotations.
3816 -- They are necessary in any case to insure order of elaboration
3819 if not Is_Frozen (Spec_Id)
3820 and then (Expander_Active
3822 or else (Operating_Mode = Check_Semantics
3823 and then Serious_Errors_Detected = 0))
3825 -- The body generated for an expression function that is not a
3826 -- completion is a freeze point neither for the profile nor for
3827 -- anything else. That's why, in order to prevent any freezing
3828 -- during analysis, we need to mask types declared outside the
3829 -- expression that are not yet frozen.
3831 if Nkind (N) = N_Subprogram_Body
3832 and then Was_Expression_Function (N)
3833 and then not Has_Completion (Spec_Id)
3835 Set_Is_Frozen (Spec_Id);
3836 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3838 Set_Has_Delayed_Freeze (Spec_Id);
3839 Freeze_Before (N, Spec_Id);
3844 -- If the subprogram has a class-wide clone, build its body as a copy
3845 -- of the original body, and rewrite body of original subprogram as a
3846 -- wrapper that calls the clone.
3848 if Present (Spec_Id)
3849 and then Present (Class_Wide_Clone (Spec_Id))
3850 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3852 Build_Class_Wide_Clone_Body (Spec_Id, N);
3854 -- This is the new body for the existing primitive operation
3856 Rewrite (N, Build_Class_Wide_Clone_Call
3857 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3858 Set_Has_Completion (Spec_Id, False);
3863 -- Place subprogram on scope stack, and make formals visible. If there
3864 -- is a spec, the visible entity remains that of the spec.
3866 if Present (Spec_Id) then
3867 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3869 if Is_Child_Unit (Spec_Id) then
3870 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3874 Style.Check_Identifier (Body_Id, Spec_Id);
3877 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3878 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3880 if Is_Abstract_Subprogram (Spec_Id) then
3881 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3885 Set_Convention (Body_Id, Convention (Spec_Id));
3886 Set_Has_Completion (Spec_Id);
3888 if Is_Protected_Type (Scope (Spec_Id)) then
3889 Prot_Typ := Scope (Spec_Id);
3892 -- If this is a body generated for a renaming, do not check for
3893 -- full conformance. The check is redundant, because the spec of
3894 -- the body is a copy of the spec in the renaming declaration,
3895 -- and the test can lead to spurious errors on nested defaults.
3897 if Present (Spec_Decl)
3898 and then not Comes_From_Source (N)
3900 (Nkind (Original_Node (Spec_Decl)) =
3901 N_Subprogram_Renaming_Declaration
3902 or else (Present (Corresponding_Body (Spec_Decl))
3904 Nkind (Unit_Declaration_Node
3905 (Corresponding_Body (Spec_Decl))) =
3906 N_Subprogram_Renaming_Declaration))
3910 -- Conversely, the spec may have been generated for specless body
3911 -- with an inline pragma. The entity comes from source, which is
3912 -- both semantically correct and necessary for proper inlining.
3913 -- The subprogram declaration itself is not in the source.
3915 elsif Comes_From_Source (N)
3916 and then Present (Spec_Decl)
3917 and then not Comes_From_Source (Spec_Decl)
3918 and then Has_Pragma_Inline (Spec_Id)
3925 Fully_Conformant, True, Conformant, Body_Id);
3928 -- If the body is not fully conformant, we have to decide if we
3929 -- should analyze it or not. If it has a really messed up profile
3930 -- then we probably should not analyze it, since we will get too
3931 -- many bogus messages.
3933 -- Our decision is to go ahead in the non-fully conformant case
3934 -- only if it is at least mode conformant with the spec. Note
3935 -- that the call to Check_Fully_Conformant has issued the proper
3936 -- error messages to complain about the lack of conformance.
3939 and then not Mode_Conformant (Body_Id, Spec_Id)
3945 -- In the case we are dealing with an expression function we check
3946 -- the formals attached to the spec instead of the body - so we don't
3947 -- reference body formals.
3949 if Spec_Id /= Body_Id
3950 and then not Is_Expression_Function (Spec_Id)
3952 Reference_Body_Formals (Spec_Id, Body_Id);
3955 Set_Ekind (Body_Id, E_Subprogram_Body);
3957 if Nkind (N) = N_Subprogram_Body_Stub then
3958 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3963 Set_Corresponding_Spec (N, Spec_Id);
3965 -- Ada 2005 (AI-345): If the operation is a primitive operation
3966 -- of a concurrent type, the type of the first parameter has been
3967 -- replaced with the corresponding record, which is the proper
3968 -- run-time structure to use. However, within the body there may
3969 -- be uses of the formals that depend on primitive operations
3970 -- of the type (in particular calls in prefixed form) for which
3971 -- we need the original concurrent type. The operation may have
3972 -- several controlling formals, so the replacement must be done
3975 if Comes_From_Source (Spec_Id)
3976 and then Present (First_Entity (Spec_Id))
3977 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3978 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3979 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3980 and then Present (Corresponding_Concurrent_Type
3981 (Etype (First_Entity (Spec_Id))))
3984 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3988 Form := First_Formal (Spec_Id);
3989 while Present (Form) loop
3990 if Etype (Form) = Typ then
3991 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3999 -- Make the formals visible, and place subprogram on scope stack.
4000 -- This is also the point at which we set Last_Real_Spec_Entity
4001 -- to mark the entities which will not be moved to the body.
4003 Install_Formals (Spec_Id);
4004 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
4006 -- Within an instance, add local renaming declarations so that
4007 -- gdb can retrieve the values of actuals more easily. This is
4008 -- only relevant if generating code (and indeed we definitely
4009 -- do not want these definitions -gnatc mode, because that would
4012 if Is_Generic_Instance (Spec_Id)
4013 and then Is_Wrapper_Package (Current_Scope)
4014 and then Expander_Active
4016 Build_Subprogram_Instance_Renamings (N, Current_Scope);
4019 Push_Scope (Spec_Id);
4021 -- Make sure that the subprogram is immediately visible. For
4022 -- child units that have no separate spec this is indispensable.
4023 -- Otherwise it is safe albeit redundant.
4025 Set_Is_Immediately_Visible (Spec_Id);
4028 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
4029 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
4030 Set_Scope (Body_Id, Scope (Spec_Id));
4032 -- Case of subprogram body with no previous spec
4035 -- Check for style warning required
4039 -- Only apply check for source level subprograms for which checks
4040 -- have not been suppressed.
4042 and then Comes_From_Source (Body_Id)
4043 and then not Suppress_Style_Checks (Body_Id)
4045 -- No warnings within an instance
4047 and then not In_Instance
4049 -- No warnings for expression functions
4051 and then Nkind (Original_Node (N)) /= N_Expression_Function
4053 Style.Body_With_No_Spec (N);
4056 New_Overloaded_Entity (Body_Id);
4058 if Nkind (N) /= N_Subprogram_Body_Stub then
4059 Set_Acts_As_Spec (N);
4060 Generate_Definition (Body_Id);
4062 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
4064 -- If the body is an entry wrapper created for an entry with
4065 -- preconditions, it must be compiled in the context of the
4066 -- enclosing synchronized object, because it may mention other
4067 -- operations of the type.
4069 if Is_Entry_Wrapper (Body_Id) then
4071 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4074 Install_Declarations (Prot);
4078 Install_Formals (Body_Id);
4080 Push_Scope (Body_Id);
4083 -- For stubs and bodies with no previous spec, generate references to
4086 Generate_Reference_To_Formals (Body_Id);
4089 -- Entry barrier functions are generated outside the protected type and
4090 -- should not carry the SPARK_Mode of the enclosing context.
4092 if Nkind (N) = N_Subprogram_Body
4093 and then Is_Entry_Barrier_Function (N)
4097 -- The body is generated as part of expression function expansion. When
4098 -- the expression function appears in the visible declarations of a
4099 -- package, the body is added to the private declarations. Since both
4100 -- declarative lists may be subject to a different SPARK_Mode, inherit
4101 -- the mode of the spec.
4103 -- package P with SPARK_Mode is
4104 -- function Expr_Func ... is (...); -- original
4105 -- [function Expr_Func ...;] -- generated spec
4108 -- pragma SPARK_Mode (Off);
4109 -- [function Expr_Func ... is return ...;] -- generated body
4110 -- end P; -- mode is ON
4112 elsif not Comes_From_Source (N)
4113 and then Present (Spec_Id)
4114 and then Is_Expression_Function (Spec_Id)
4116 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4117 Set_SPARK_Pragma_Inherited
4118 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4120 -- Set the SPARK_Mode from the current context (may be overwritten later
4121 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4122 -- initially on a stand-alone subprogram body, but is then relocated to
4123 -- a generated corresponding spec. In this scenario the mode is shared
4124 -- between the spec and body.
4126 elsif No (SPARK_Pragma (Body_Id)) then
4127 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4128 Set_SPARK_Pragma_Inherited (Body_Id);
4131 -- A subprogram body may be instantiated or inlined at a later pass.
4132 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4133 -- applied to the initial declaration of the body.
4135 if Present (Spec_Id) then
4136 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4137 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4141 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4142 -- case the body is instantiated or inlined later and out of context.
4143 -- The body uses this attribute to restore the value of the global
4146 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4147 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4149 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4150 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4154 -- Preserve relevant elaboration-related attributes of the context which
4155 -- are no longer available or very expensive to recompute once analysis,
4156 -- resolution, and expansion are over.
4158 if No (Spec_Id) then
4159 Mark_Elaboration_Attributes
4165 -- If this is the proper body of a stub, we must verify that the stub
4166 -- conforms to the body, and to the previous spec if one was present.
4167 -- We know already that the body conforms to that spec. This test is
4168 -- only required for subprograms that come from source.
4170 if Nkind (Parent (N)) = N_Subunit
4171 and then Comes_From_Source (N)
4172 and then not Error_Posted (Body_Id)
4173 and then Nkind (Corresponding_Stub (Parent (N))) =
4174 N_Subprogram_Body_Stub
4177 Old_Id : constant Entity_Id :=
4179 (Specification (Corresponding_Stub (Parent (N))));
4181 Conformant : Boolean := False;
4184 if No (Spec_Id) then
4185 Check_Fully_Conformant (Body_Id, Old_Id);
4189 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4191 if not Conformant then
4193 -- The stub was taken to be a new declaration. Indicate that
4196 Set_Has_Completion (Old_Id, False);
4202 Set_Has_Completion (Body_Id);
4203 Check_Eliminated (Body_Id);
4205 -- Analyze any aspect specifications that appear on the subprogram body
4206 -- stub. Stop the analysis now as the stub does not have a declarative
4207 -- or a statement part, and it cannot be inlined.
4209 if Nkind (N) = N_Subprogram_Body_Stub then
4210 if Has_Aspects (N) then
4211 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4219 -- Note: Normally we don't do any inlining if expansion is off, since
4220 -- we won't generate code in any case. An exception arises in GNATprove
4221 -- mode where we want to expand some calls in place, even with expansion
4222 -- disabled, since the inlining eases formal verification.
4224 if not GNATprove_Mode
4225 and then Expander_Active
4226 and then Serious_Errors_Detected = 0
4227 and then Present (Spec_Id)
4228 and then Has_Pragma_Inline (Spec_Id)
4230 -- Legacy implementation (relying on front-end inlining)
4232 if not Back_End_Inlining then
4233 if (Has_Pragma_Inline_Always (Spec_Id)
4234 and then not Opt.Disable_FE_Inline_Always)
4235 or else (Front_End_Inlining
4236 and then not Opt.Disable_FE_Inline)
4238 Build_Body_To_Inline (N, Spec_Id);
4241 -- New implementation (relying on back-end inlining)
4244 if Has_Pragma_Inline_Always (Spec_Id)
4245 or else Optimization_Level > 0
4247 -- Handle function returning an unconstrained type
4249 if Comes_From_Source (Body_Id)
4250 and then Ekind (Spec_Id) = E_Function
4251 and then Returns_Unconstrained_Type (Spec_Id)
4253 -- If function builds in place, i.e. returns a limited type,
4254 -- inlining cannot be done.
4256 and then not Is_Limited_Type (Etype (Spec_Id))
4258 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4262 Subp_Body : constant Node_Id :=
4263 Unit_Declaration_Node (Body_Id);
4264 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4267 -- Do not pass inlining to the backend if the subprogram
4268 -- has declarations or statements which cannot be inlined
4269 -- by the backend. This check is done here to emit an
4270 -- error instead of the generic warning message reported
4271 -- by the GCC backend (ie. "function might not be
4274 if Present (Subp_Decl)
4275 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4279 elsif Has_Excluded_Statement
4282 (Handled_Statement_Sequence (Subp_Body)))
4286 -- If the backend inlining is available then at this
4287 -- stage we only have to mark the subprogram as inlined.
4288 -- The expander will take care of registering it in the
4289 -- table of subprograms inlined by the backend a part of
4290 -- processing calls to it (cf. Expand_Call)
4293 Set_Is_Inlined (Spec_Id);
4300 -- In GNATprove mode, inline only when there is a separate subprogram
4301 -- declaration for now, as inlining of subprogram bodies acting as
4302 -- declarations, or subprogram stubs, are not supported by front-end
4303 -- inlining. This inlining should occur after analysis of the body, so
4304 -- that it is known whether the value of SPARK_Mode, which can be
4305 -- defined by a pragma inside the body, is applicable to the body.
4306 -- Inlining can be disabled with switch -gnatdm
4308 elsif GNATprove_Mode
4309 and then Full_Analysis
4310 and then not Inside_A_Generic
4311 and then Present (Spec_Id)
4313 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4314 and then Body_Has_SPARK_Mode_On
4315 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4316 and then not Body_Has_Contract
4317 and then not Debug_Flag_M
4319 Build_Body_To_Inline (N, Spec_Id);
4322 -- When generating code, inherited pre/postconditions are handled when
4323 -- expanding the corresponding contract.
4325 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4326 -- of the specification we have to install the private withed units.
4327 -- This holds for child units as well.
4329 if Is_Compilation_Unit (Body_Id)
4330 or else Nkind (Parent (N)) = N_Compilation_Unit
4332 Install_Private_With_Clauses (Body_Id);
4335 Check_Anonymous_Return;
4337 -- Set the Protected_Formal field of each extra formal of the protected
4338 -- subprogram to reference the corresponding extra formal of the
4339 -- subprogram that implements it. For regular formals this occurs when
4340 -- the protected subprogram's declaration is expanded, but the extra
4341 -- formals don't get created until the subprogram is frozen. We need to
4342 -- do this before analyzing the protected subprogram's body so that any
4343 -- references to the original subprogram's extra formals will be changed
4344 -- refer to the implementing subprogram's formals (see Expand_Formal).
4346 if Present (Spec_Id)
4347 and then Is_Protected_Type (Scope (Spec_Id))
4348 and then Present (Protected_Body_Subprogram (Spec_Id))
4351 Impl_Subp : constant Entity_Id :=
4352 Protected_Body_Subprogram (Spec_Id);
4353 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4354 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4357 while Present (Prot_Ext_Formal) loop
4358 pragma Assert (Present (Impl_Ext_Formal));
4359 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4360 Next_Formal_With_Extras (Prot_Ext_Formal);
4361 Next_Formal_With_Extras (Impl_Ext_Formal);
4366 -- Now we can go on to analyze the body
4368 HSS := Handled_Statement_Sequence (N);
4369 Set_Actual_Subtypes (N, Current_Scope);
4371 -- Add a declaration for the Protection object, renaming declarations
4372 -- for discriminals and privals and finally a declaration for the entry
4373 -- family index (if applicable). This form of early expansion is done
4374 -- when the Expander is active because Install_Private_Data_Declarations
4375 -- references entities which were created during regular expansion. The
4376 -- subprogram entity must come from source, and not be an internally
4377 -- generated subprogram.
4380 and then Present (Prot_Typ)
4381 and then Present (Spec_Id)
4382 and then Comes_From_Source (Spec_Id)
4383 and then not Is_Eliminated (Spec_Id)
4385 Install_Private_Data_Declarations
4386 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4389 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4390 -- may now appear in parameter and result profiles. Since the analysis
4391 -- of a subprogram body may use the parameter and result profile of the
4392 -- spec, swap any limited views with their non-limited counterpart.
4394 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4395 Exch_Views := Exchange_Limited_Views (Spec_Id);
4398 -- If the return type is an anonymous access type whose designated type
4399 -- is the limited view of a class-wide type and the non-limited view is
4400 -- available, update the return type accordingly.
4402 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4408 Rtyp := Etype (Spec_Id);
4410 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4411 Etyp := Directly_Designated_Type (Rtyp);
4413 if Is_Class_Wide_Type (Etyp)
4414 and then From_Limited_With (Etyp)
4417 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4423 -- Analyze any aspect specifications that appear on the subprogram body
4425 if Has_Aspects (N) then
4426 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4429 Analyze_Declarations (Declarations (N));
4431 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4433 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4434 if Present (SPARK_Pragma (Spec_Id)) then
4435 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4437 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4439 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4440 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4441 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4443 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4446 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4450 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4451 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4452 Error_Msg_Sloc := Sloc (Spec_Id);
4454 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4458 -- A subprogram body freezes its own contract. Analyze the contract
4459 -- after the declarations of the body have been processed as pragmas
4460 -- are now chained on the contract of the subprogram body.
4462 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4464 -- Check completion, and analyze the statements
4467 Inspect_Deferred_Constant_Completion (Declarations (N));
4470 -- Deal with end of scope processing for the body
4472 Process_End_Label (HSS, 't', Current_Scope);
4473 Update_Use_Clause_Chain;
4476 -- If we are compiling an entry wrapper, remove the enclosing
4477 -- synchronized object from the stack.
4479 if Is_Entry_Wrapper (Body_Id) then
4483 Check_Subprogram_Order (N);
4484 Set_Analyzed (Body_Id);
4486 -- If we have a separate spec, then the analysis of the declarations
4487 -- caused the entities in the body to be chained to the spec id, but
4488 -- we want them chained to the body id. Only the formal parameters
4489 -- end up chained to the spec id in this case.
4491 if Present (Spec_Id) then
4493 -- We must conform to the categorization of our spec
4495 Validate_Categorization_Dependency (N, Spec_Id);
4497 -- And if this is a child unit, the parent units must conform
4499 if Is_Child_Unit (Spec_Id) then
4500 Validate_Categorization_Dependency
4501 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4504 -- Here is where we move entities from the spec to the body
4506 -- Case where there are entities that stay with the spec
4508 if Present (Last_Real_Spec_Entity) then
4510 -- No body entities (happens when the only real spec entities come
4511 -- from precondition and postcondition pragmas).
4513 if No (Last_Entity (Body_Id)) then
4514 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4516 -- Body entities present (formals), so chain stuff past them
4520 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4523 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4524 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4525 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4527 -- Case where there are no spec entities, in this case there can be
4528 -- no body entities either, so just move everything.
4530 -- If the body is generated for an expression function, it may have
4531 -- been preanalyzed already, if 'access was applied to it.
4534 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4535 N_Expression_Function
4537 pragma Assert (No (Last_Entity (Body_Id)));
4541 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4542 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4543 Set_First_Entity (Spec_Id, Empty);
4544 Set_Last_Entity (Spec_Id, Empty);
4547 -- Otherwise the body does not complete a previous declaration. Check
4548 -- the categorization of the body against the units it withs.
4551 Validate_Categorization_Dependency (N, Body_Id);
4554 Check_Missing_Return;
4556 -- Now we are going to check for variables that are never modified in
4557 -- the body of the procedure. But first we deal with a special case
4558 -- where we want to modify this check. If the body of the subprogram
4559 -- starts with a raise statement or its equivalent, or if the body
4560 -- consists entirely of a null statement, then it is pretty obvious that
4561 -- it is OK to not reference the parameters. For example, this might be
4562 -- the following common idiom for a stubbed function: statement of the
4563 -- procedure raises an exception. In particular this deals with the
4564 -- common idiom of a stubbed function, which appears something like:
4566 -- function F (A : Integer) return Some_Type;
4569 -- raise Program_Error;
4573 -- Here the purpose of X is simply to satisfy the annoying requirement
4574 -- in Ada that there be at least one return, and we certainly do not
4575 -- want to go posting warnings on X that it is not initialized. On
4576 -- the other hand, if X is entirely unreferenced that should still
4579 -- What we do is to detect these cases, and if we find them, flag the
4580 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4581 -- suppress unwanted warnings. For the case of the function stub above
4582 -- we have a special test to set X as apparently assigned to suppress
4589 -- Skip call markers installed by the ABE mechanism, labels, and
4590 -- Push_xxx_Error_Label to find the first real statement.
4592 Stm := First (Statements (HSS));
4593 while Nkind_In (Stm, N_Call_Marker, N_Label)
4594 or else Nkind (Stm) in N_Push_xxx_Label
4599 -- Do the test on the original statement before expansion
4602 Ostm : constant Node_Id := Original_Node (Stm);
4605 -- If explicit raise statement, turn on flag
4607 if Nkind (Ostm) = N_Raise_Statement then
4608 Set_Trivial_Subprogram (Stm);
4610 -- If null statement, and no following statements, turn on flag
4612 elsif Nkind (Stm) = N_Null_Statement
4613 and then Comes_From_Source (Stm)
4614 and then No (Next (Stm))
4616 Set_Trivial_Subprogram (Stm);
4618 -- Check for explicit call cases which likely raise an exception
4620 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4621 if Is_Entity_Name (Name (Ostm)) then
4623 Ent : constant Entity_Id := Entity (Name (Ostm));
4626 -- If the procedure is marked No_Return, then likely it
4627 -- raises an exception, but in any case it is not coming
4628 -- back here, so turn on the flag.
4631 and then Ekind (Ent) = E_Procedure
4632 and then No_Return (Ent)
4634 Set_Trivial_Subprogram (Stm);
4642 -- Check for variables that are never modified
4649 -- If there is a separate spec, then transfer Never_Set_In_Source
4650 -- flags from out parameters to the corresponding entities in the
4651 -- body. The reason we do that is we want to post error flags on
4652 -- the body entities, not the spec entities.
4654 if Present (Spec_Id) then
4655 E1 := First_Entity (Spec_Id);
4656 while Present (E1) loop
4657 if Ekind (E1) = E_Out_Parameter then
4658 E2 := First_Entity (Body_Id);
4659 while Present (E2) loop
4660 exit when Chars (E1) = Chars (E2);
4664 if Present (E2) then
4665 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4673 -- Check references of the subprogram spec when we are dealing with
4674 -- an expression function due to it having a generated body.
4675 -- Otherwise, we simply check the formals of the subprogram body.
4677 if Present (Spec_Id)
4678 and then Is_Expression_Function (Spec_Id)
4680 Check_References (Spec_Id);
4682 Check_References (Body_Id);
4686 -- Check for nested subprogram, and mark outer level subprogram if so
4692 if Present (Spec_Id) then
4699 Ent := Enclosing_Subprogram (Ent);
4700 exit when No (Ent) or else Is_Subprogram (Ent);
4703 if Present (Ent) then
4704 Set_Has_Nested_Subprogram (Ent);
4708 -- Restore the limited views in the spec, if any, to let the back end
4709 -- process it without running into circularities.
4711 if Exch_Views /= No_Elist then
4712 Restore_Limited_Views (Exch_Views);
4715 if Mask_Types /= No_Elist then
4716 Unmask_Unfrozen_Types (Mask_Types);
4719 if Present (Desig_View) then
4720 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4724 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4725 Restore_Ghost_Region (Saved_GM, Saved_IGR);
4726 end Analyze_Subprogram_Body_Helper;
4728 ------------------------------------
4729 -- Analyze_Subprogram_Declaration --
4730 ------------------------------------
4732 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4733 Scop : constant Entity_Id := Current_Scope;
4734 Designator : Entity_Id;
4736 Is_Completion : Boolean;
4737 -- Indicates whether a null procedure declaration is a completion
4740 -- Null procedures are not allowed in SPARK
4742 if Nkind (Specification (N)) = N_Procedure_Specification
4743 and then Null_Present (Specification (N))
4745 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4747 -- Null procedures are allowed in protected types, following the
4748 -- recent AI12-0147.
4750 if Is_Protected_Type (Current_Scope)
4751 and then Ada_Version < Ada_2012
4753 Error_Msg_N ("protected operation cannot be a null procedure", N);
4756 Analyze_Null_Procedure (N, Is_Completion);
4758 -- The null procedure acts as a body, nothing further is needed
4760 if Is_Completion then
4765 Designator := Analyze_Subprogram_Specification (Specification (N));
4767 -- A reference may already have been generated for the unit name, in
4768 -- which case the following call is redundant. However it is needed for
4769 -- declarations that are the rewriting of an expression function.
4771 Generate_Definition (Designator);
4773 -- Set the SPARK mode from the current context (may be overwritten later
4774 -- with explicit pragma). This is not done for entry barrier functions
4775 -- because they are generated outside the protected type and should not
4776 -- carry the mode of the enclosing context.
4778 if Nkind (N) = N_Subprogram_Declaration
4779 and then Is_Entry_Barrier_Function (N)
4784 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4785 Set_SPARK_Pragma_Inherited (Designator);
4788 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4789 -- the body of this subprogram is instantiated or inlined later and out
4790 -- of context. The body uses this attribute to restore the value of the
4793 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4794 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4797 -- Preserve relevant elaboration-related attributes of the context which
4798 -- are no longer available or very expensive to recompute once analysis,
4799 -- resolution, and expansion are over.
4801 Mark_Elaboration_Attributes
4802 (N_Id => Designator,
4806 if Debug_Flag_C then
4807 Write_Str ("==> subprogram spec ");
4808 Write_Name (Chars (Designator));
4809 Write_Str (" from ");
4810 Write_Location (Sloc (N));
4815 Validate_RCI_Subprogram_Declaration (N);
4816 New_Overloaded_Entity (Designator);
4817 Check_Delayed_Subprogram (Designator);
4819 -- If the type of the first formal of the current subprogram is a non-
4820 -- generic tagged private type, mark the subprogram as being a private
4821 -- primitive. Ditto if this is a function with controlling result, and
4822 -- the return type is currently private. In both cases, the type of the
4823 -- controlling argument or result must be in the current scope for the
4824 -- operation to be primitive.
4826 if Has_Controlling_Result (Designator)
4827 and then Is_Private_Type (Etype (Designator))
4828 and then Scope (Etype (Designator)) = Current_Scope
4829 and then not Is_Generic_Actual_Type (Etype (Designator))
4831 Set_Is_Private_Primitive (Designator);
4833 elsif Present (First_Formal (Designator)) then
4835 Formal_Typ : constant Entity_Id :=
4836 Etype (First_Formal (Designator));
4838 Set_Is_Private_Primitive (Designator,
4839 Is_Tagged_Type (Formal_Typ)
4840 and then Scope (Formal_Typ) = Current_Scope
4841 and then Is_Private_Type (Formal_Typ)
4842 and then not Is_Generic_Actual_Type (Formal_Typ));
4846 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4849 if Ada_Version >= Ada_2005
4850 and then Comes_From_Source (N)
4851 and then Is_Dispatching_Operation (Designator)
4858 if Has_Controlling_Result (Designator) then
4859 Etyp := Etype (Designator);
4862 E := First_Entity (Designator);
4864 and then Is_Formal (E)
4865 and then not Is_Controlling_Formal (E)
4873 if Is_Access_Type (Etyp) then
4874 Etyp := Directly_Designated_Type (Etyp);
4877 if Is_Interface (Etyp)
4878 and then not Is_Abstract_Subprogram (Designator)
4879 and then not (Ekind (Designator) = E_Procedure
4880 and then Null_Present (Specification (N)))
4882 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4884 -- Specialize error message based on procedures vs. functions,
4885 -- since functions can't be null subprograms.
4887 if Ekind (Designator) = E_Procedure then
4889 ("interface procedure % must be abstract or null", N);
4892 ("interface function % must be abstract", N);
4898 -- What is the following code for, it used to be
4900 -- ??? Set_Suppress_Elaboration_Checks
4901 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4903 -- The following seems equivalent, but a bit dubious
4905 if Elaboration_Checks_Suppressed (Designator) then
4906 Set_Kill_Elaboration_Checks (Designator);
4909 -- For a compilation unit, set body required. This flag will only be
4910 -- reset if a valid Import or Interface pragma is processed later on.
4912 if Nkind (Parent (N)) = N_Compilation_Unit then
4913 Set_Body_Required (Parent (N), True);
4915 if Ada_Version >= Ada_2005
4916 and then Nkind (Specification (N)) = N_Procedure_Specification
4917 and then Null_Present (Specification (N))
4920 ("null procedure cannot be declared at library level", N);
4924 Generate_Reference_To_Formals (Designator);
4925 Check_Eliminated (Designator);
4927 if Debug_Flag_C then
4929 Write_Str ("<== subprogram spec ");
4930 Write_Name (Chars (Designator));
4931 Write_Str (" from ");
4932 Write_Location (Sloc (N));
4936 -- Indicate that this is a protected operation, because it may be used
4937 -- in subsequent declarations within the protected type.
4939 if Is_Protected_Type (Current_Scope) then
4940 Set_Convention (Designator, Convention_Protected);
4943 List_Inherited_Pre_Post_Aspects (Designator);
4945 -- Process the aspects before establishing the proper categorization in
4946 -- case the subprogram is a compilation unit and one of its aspects is
4947 -- converted into a categorization pragma.
4949 if Has_Aspects (N) then
4950 Analyze_Aspect_Specifications (N, Designator);
4953 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4954 Set_Categorization_From_Scope (Designator, Scop);
4956 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4957 -- proper categorization of the unit based on its pragmas.
4960 Push_Scope (Designator);
4961 Set_Categorization_From_Pragmas (N);
4962 Validate_Categorization_Dependency (N, Designator);
4965 end Analyze_Subprogram_Declaration;
4967 --------------------------------------
4968 -- Analyze_Subprogram_Specification --
4969 --------------------------------------
4971 -- Reminder: N here really is a subprogram specification (not a subprogram
4972 -- declaration). This procedure is called to analyze the specification in
4973 -- both subprogram bodies and subprogram declarations (specs).
4975 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4976 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4977 -- Determine whether entity E denotes the spec or body of an invariant
4980 ------------------------------------
4981 -- Is_Invariant_Procedure_Or_Body --
4982 ------------------------------------
4984 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4985 Decl : constant Node_Id := Unit_Declaration_Node (E);
4989 if Nkind (Decl) = N_Subprogram_Body then
4990 Spec := Corresponding_Spec (Decl);
4997 and then Ekind (Spec) = E_Procedure
4998 and then (Is_Partial_Invariant_Procedure (Spec)
4999 or else Is_Invariant_Procedure (Spec));
5000 end Is_Invariant_Procedure_Or_Body;
5004 Designator : constant Entity_Id := Defining_Entity (N);
5005 Formals : constant List_Id := Parameter_Specifications (N);
5007 -- Start of processing for Analyze_Subprogram_Specification
5010 -- User-defined operator is not allowed in SPARK, except as a renaming
5012 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
5013 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
5015 Check_SPARK_05_Restriction
5016 ("user-defined operator is not allowed", N);
5019 -- Proceed with analysis. Do not emit a cross-reference entry if the
5020 -- specification comes from an expression function, because it may be
5021 -- the completion of a previous declaration. If it is not, the cross-
5022 -- reference entry will be emitted for the new subprogram declaration.
5024 if Nkind (Parent (N)) /= N_Expression_Function then
5025 Generate_Definition (Designator);
5028 if Nkind (N) = N_Function_Specification then
5029 Set_Ekind (Designator, E_Function);
5030 Set_Mechanism (Designator, Default_Mechanism);
5032 Set_Ekind (Designator, E_Procedure);
5033 Set_Etype (Designator, Standard_Void_Type);
5036 -- Flag Is_Inlined_Always is True by default, and reversed to False for
5037 -- those subprograms which could be inlined in GNATprove mode (because
5038 -- Body_To_Inline is non-Empty) but should not be inlined.
5040 if GNATprove_Mode then
5041 Set_Is_Inlined_Always (Designator);
5044 -- Introduce new scope for analysis of the formals and the return type
5046 Set_Scope (Designator, Current_Scope);
5048 if Present (Formals) then
5049 Push_Scope (Designator);
5050 Process_Formals (Formals, N);
5052 -- Check dimensions in N for formals with default expression
5054 Analyze_Dimension_Formals (N, Formals);
5056 -- Ada 2005 (AI-345): If this is an overriding operation of an
5057 -- inherited interface operation, and the controlling type is
5058 -- a synchronized type, replace the type with its corresponding
5059 -- record, to match the proper signature of an overriding operation.
5060 -- Same processing for an access parameter whose designated type is
5061 -- derived from a synchronized interface.
5063 -- This modification is not done for invariant procedures because
5064 -- the corresponding record may not necessarely be visible when the
5065 -- concurrent type acts as the full view of a private type.
5068 -- type Prot is private with Type_Invariant => ...;
5069 -- procedure ConcInvariant (Obj : Prot);
5071 -- protected type Prot is ...;
5072 -- type Concurrent_Record_Prot is record ...;
5073 -- procedure ConcInvariant (Obj : Prot) is
5075 -- end ConcInvariant;
5078 -- In the example above, both the spec and body of the invariant
5079 -- procedure must utilize the private type as the controlling type.
5081 if Ada_Version >= Ada_2005
5082 and then not Is_Invariant_Procedure_Or_Body (Designator)
5086 Formal_Typ : Entity_Id;
5087 Rec_Typ : Entity_Id;
5088 Desig_Typ : Entity_Id;
5091 Formal := First_Formal (Designator);
5092 while Present (Formal) loop
5093 Formal_Typ := Etype (Formal);
5095 if Is_Concurrent_Type (Formal_Typ)
5096 and then Present (Corresponding_Record_Type (Formal_Typ))
5098 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5100 if Present (Interfaces (Rec_Typ)) then
5101 Set_Etype (Formal, Rec_Typ);
5104 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5105 Desig_Typ := Designated_Type (Formal_Typ);
5107 if Is_Concurrent_Type (Desig_Typ)
5108 and then Present (Corresponding_Record_Type (Desig_Typ))
5110 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5112 if Present (Interfaces (Rec_Typ)) then
5113 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5118 Next_Formal (Formal);
5125 -- The subprogram scope is pushed and popped around the processing of
5126 -- the return type for consistency with call above to Process_Formals
5127 -- (which itself can call Analyze_Return_Type), and to ensure that any
5128 -- itype created for the return type will be associated with the proper
5131 elsif Nkind (N) = N_Function_Specification then
5132 Push_Scope (Designator);
5133 Analyze_Return_Type (N);
5139 if Nkind (N) = N_Function_Specification then
5141 -- Deal with operator symbol case
5143 if Nkind (Designator) = N_Defining_Operator_Symbol then
5144 Valid_Operator_Definition (Designator);
5147 May_Need_Actuals (Designator);
5149 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5150 -- the subprogram is abstract also. This does not apply to renaming
5151 -- declarations, where abstractness is inherited, and to subprogram
5152 -- bodies generated for stream operations, which become renamings as
5155 -- In case of primitives associated with abstract interface types
5156 -- the check is applied later (see Analyze_Subprogram_Declaration).
5158 if not Nkind_In (Original_Node (Parent (N)),
5159 N_Abstract_Subprogram_Declaration,
5160 N_Formal_Abstract_Subprogram_Declaration,
5161 N_Subprogram_Renaming_Declaration)
5163 if Is_Abstract_Type (Etype (Designator))
5164 and then not Is_Interface (Etype (Designator))
5167 ("function that returns abstract type must be abstract", N);
5169 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5170 -- access result whose designated type is abstract.
5172 elsif Ada_Version >= Ada_2012
5173 and then Nkind (Result_Definition (N)) = N_Access_Definition
5175 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5176 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5179 ("function whose access result designates abstract type "
5180 & "must be abstract", N);
5186 end Analyze_Subprogram_Specification;
5188 -----------------------
5189 -- Check_Conformance --
5190 -----------------------
5192 procedure Check_Conformance
5193 (New_Id : Entity_Id;
5195 Ctype : Conformance_Type;
5197 Conforms : out Boolean;
5198 Err_Loc : Node_Id := Empty;
5199 Get_Inst : Boolean := False;
5200 Skip_Controlling_Formals : Boolean := False)
5202 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5203 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5204 -- If Errmsg is True, then processing continues to post an error message
5205 -- for conformance error on given node. Two messages are output. The
5206 -- first message points to the previous declaration with a general "no
5207 -- conformance" message. The second is the detailed reason, supplied as
5208 -- Msg. The parameter N provide information for a possible & insertion
5209 -- in the message, and also provides the location for posting the
5210 -- message in the absence of a specified Err_Loc location.
5212 function Conventions_Match
5214 Id2 : Entity_Id) return Boolean;
5215 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5218 -----------------------
5219 -- Conformance_Error --
5220 -----------------------
5222 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5229 if No (Err_Loc) then
5235 Error_Msg_Sloc := Sloc (Old_Id);
5238 when Type_Conformant =>
5239 Error_Msg_N -- CODEFIX
5240 ("not type conformant with declaration#!", Enode);
5242 when Mode_Conformant =>
5243 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5245 ("not mode conformant with operation inherited#!",
5249 ("not mode conformant with declaration#!", Enode);
5252 when Subtype_Conformant =>
5253 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5255 ("not subtype conformant with operation inherited#!",
5259 ("not subtype conformant with declaration#!", Enode);
5262 when Fully_Conformant =>
5263 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5264 Error_Msg_N -- CODEFIX
5265 ("not fully conformant with operation inherited#!",
5268 Error_Msg_N -- CODEFIX
5269 ("not fully conformant with declaration#!", Enode);
5273 Error_Msg_NE (Msg, Enode, N);
5275 end Conformance_Error;
5277 -----------------------
5278 -- Conventions_Match --
5279 -----------------------
5281 function Conventions_Match
5283 Id2 : Entity_Id) return Boolean
5286 -- Ignore the conventions of anonymous access-to-subprogram types
5287 -- and subprogram types because these are internally generated and
5288 -- the only way these may receive a convention is if they inherit
5289 -- the convention of a related subprogram.
5291 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5294 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5299 -- Otherwise compare the conventions directly
5302 return Convention (Id1) = Convention (Id2);
5304 end Conventions_Match;
5308 Old_Type : constant Entity_Id := Etype (Old_Id);
5309 New_Type : constant Entity_Id := Etype (New_Id);
5310 Old_Formal : Entity_Id;
5311 New_Formal : Entity_Id;
5312 Access_Types_Match : Boolean;
5313 Old_Formal_Base : Entity_Id;
5314 New_Formal_Base : Entity_Id;
5316 -- Start of processing for Check_Conformance
5321 -- We need a special case for operators, since they don't appear
5324 if Ctype = Type_Conformant then
5325 if Ekind (New_Id) = E_Operator
5326 and then Operator_Matches_Spec (New_Id, Old_Id)
5332 -- If both are functions/operators, check return types conform
5334 if Old_Type /= Standard_Void_Type
5336 New_Type /= Standard_Void_Type
5338 -- If we are checking interface conformance we omit controlling
5339 -- arguments and result, because we are only checking the conformance
5340 -- of the remaining parameters.
5342 if Has_Controlling_Result (Old_Id)
5343 and then Has_Controlling_Result (New_Id)
5344 and then Skip_Controlling_Formals
5348 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5349 if Ctype >= Subtype_Conformant
5350 and then not Predicates_Match (Old_Type, New_Type)
5353 ("\predicate of return type does not match!", New_Id);
5356 ("\return type does not match!", New_Id);
5362 -- Ada 2005 (AI-231): In case of anonymous access types check the
5363 -- null-exclusion and access-to-constant attributes match.
5365 if Ada_Version >= Ada_2005
5366 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5368 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5369 or else Is_Access_Constant (Etype (Old_Type)) /=
5370 Is_Access_Constant (Etype (New_Type)))
5372 Conformance_Error ("\return type does not match!", New_Id);
5376 -- If either is a function/operator and the other isn't, error
5378 elsif Old_Type /= Standard_Void_Type
5379 or else New_Type /= Standard_Void_Type
5381 Conformance_Error ("\functions can only match functions!", New_Id);
5385 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5386 -- If this is a renaming as body, refine error message to indicate that
5387 -- the conflict is with the original declaration. If the entity is not
5388 -- frozen, the conventions don't have to match, the one of the renamed
5389 -- entity is inherited.
5391 if Ctype >= Subtype_Conformant then
5392 if not Conventions_Match (Old_Id, New_Id) then
5393 if not Is_Frozen (New_Id) then
5396 elsif Present (Err_Loc)
5397 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5398 and then Present (Corresponding_Spec (Err_Loc))
5400 Error_Msg_Name_1 := Chars (New_Id);
5402 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5403 Conformance_Error ("\prior declaration for% has convention %!");
5406 Conformance_Error ("\calling conventions do not match!");
5411 elsif Is_Formal_Subprogram (Old_Id)
5412 or else Is_Formal_Subprogram (New_Id)
5413 or else (Is_Subprogram (New_Id)
5414 and then Present (Alias (New_Id))
5415 and then Is_Formal_Subprogram (Alias (New_Id)))
5418 ("\formal subprograms are not subtype conformant "
5419 & "(RM 6.3.1 (17/3))");
5423 -- Deal with parameters
5425 -- Note: we use the entity information, rather than going directly
5426 -- to the specification in the tree. This is not only simpler, but
5427 -- absolutely necessary for some cases of conformance tests between
5428 -- operators, where the declaration tree simply does not exist.
5430 Old_Formal := First_Formal (Old_Id);
5431 New_Formal := First_Formal (New_Id);
5432 while Present (Old_Formal) and then Present (New_Formal) loop
5433 if Is_Controlling_Formal (Old_Formal)
5434 and then Is_Controlling_Formal (New_Formal)
5435 and then Skip_Controlling_Formals
5437 -- The controlling formals will have different types when
5438 -- comparing an interface operation with its match, but both
5439 -- or neither must be access parameters.
5441 if Is_Access_Type (Etype (Old_Formal))
5443 Is_Access_Type (Etype (New_Formal))
5445 goto Skip_Controlling_Formal;
5448 ("\access parameter does not match!", New_Formal);
5452 -- Ada 2012: Mode conformance also requires that formal parameters
5453 -- be both aliased, or neither.
5455 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5456 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5458 ("\aliased parameter mismatch!", New_Formal);
5462 if Ctype = Fully_Conformant then
5464 -- Names must match. Error message is more accurate if we do
5465 -- this before checking that the types of the formals match.
5467 if Chars (Old_Formal) /= Chars (New_Formal) then
5468 Conformance_Error ("\name& does not match!", New_Formal);
5470 -- Set error posted flag on new formal as well to stop
5471 -- junk cascaded messages in some cases.
5473 Set_Error_Posted (New_Formal);
5477 -- Null exclusion must match
5479 if Null_Exclusion_Present (Parent (Old_Formal))
5481 Null_Exclusion_Present (Parent (New_Formal))
5483 -- Only give error if both come from source. This should be
5484 -- investigated some time, since it should not be needed ???
5486 if Comes_From_Source (Old_Formal)
5488 Comes_From_Source (New_Formal)
5491 ("\null exclusion for& does not match", New_Formal);
5493 -- Mark error posted on the new formal to avoid duplicated
5494 -- complaint about types not matching.
5496 Set_Error_Posted (New_Formal);
5501 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5502 -- case occurs whenever a subprogram is being renamed and one of its
5503 -- parameters imposes a null exclusion. For example:
5505 -- type T is null record;
5506 -- type Acc_T is access T;
5507 -- subtype Acc_T_Sub is Acc_T;
5509 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5510 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5513 Old_Formal_Base := Etype (Old_Formal);
5514 New_Formal_Base := Etype (New_Formal);
5517 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5518 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5521 Access_Types_Match := Ada_Version >= Ada_2005
5523 -- Ensure that this rule is only applied when New_Id is a
5524 -- renaming of Old_Id.
5526 and then Nkind (Parent (Parent (New_Id))) =
5527 N_Subprogram_Renaming_Declaration
5528 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5529 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5530 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5532 -- Now handle the allowed access-type case
5534 and then Is_Access_Type (Old_Formal_Base)
5535 and then Is_Access_Type (New_Formal_Base)
5537 -- The type kinds must match. The only exception occurs with
5538 -- multiple generics of the form:
5541 -- type F is private; type A is private;
5542 -- type F_Ptr is access F; type A_Ptr is access A;
5543 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5544 -- package F_Pack is ... package A_Pack is
5545 -- package F_Inst is
5546 -- new F_Pack (A, A_Ptr, A_P);
5548 -- When checking for conformance between the parameters of A_P
5549 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5550 -- because the compiler has transformed A_Ptr into a subtype of
5551 -- F_Ptr. We catch this case in the code below.
5553 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5555 (Is_Generic_Type (Old_Formal_Base)
5556 and then Is_Generic_Type (New_Formal_Base)
5557 and then Is_Internal (New_Formal_Base)
5558 and then Etype (Etype (New_Formal_Base)) =
5560 and then Directly_Designated_Type (Old_Formal_Base) =
5561 Directly_Designated_Type (New_Formal_Base)
5562 and then ((Is_Itype (Old_Formal_Base)
5563 and then Can_Never_Be_Null (Old_Formal_Base))
5565 (Is_Itype (New_Formal_Base)
5566 and then Can_Never_Be_Null (New_Formal_Base)));
5568 -- Types must always match. In the visible part of an instance,
5569 -- usual overloading rules for dispatching operations apply, and
5570 -- we check base types (not the actual subtypes).
5572 if In_Instance_Visible_Part
5573 and then Is_Dispatching_Operation (New_Id)
5575 if not Conforming_Types
5576 (T1 => Base_Type (Etype (Old_Formal)),
5577 T2 => Base_Type (Etype (New_Formal)),
5579 Get_Inst => Get_Inst)
5580 and then not Access_Types_Match
5582 Conformance_Error ("\type of & does not match!", New_Formal);
5586 elsif not Conforming_Types
5587 (T1 => Old_Formal_Base,
5588 T2 => New_Formal_Base,
5590 Get_Inst => Get_Inst)
5591 and then not Access_Types_Match
5593 -- Don't give error message if old type is Any_Type. This test
5594 -- avoids some cascaded errors, e.g. in case of a bad spec.
5596 if Errmsg and then Old_Formal_Base = Any_Type then
5599 if Ctype >= Subtype_Conformant
5601 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5604 ("\predicate of & does not match!", New_Formal);
5607 ("\type of & does not match!", New_Formal);
5609 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5611 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5619 -- For mode conformance, mode must match
5621 if Ctype >= Mode_Conformant then
5622 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5623 if not Ekind_In (New_Id, E_Function, E_Procedure)
5624 or else not Is_Primitive_Wrapper (New_Id)
5626 Conformance_Error ("\mode of & does not match!", New_Formal);
5630 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5632 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5634 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5637 ("\mode of & does not match!", New_Formal);
5644 -- Part of mode conformance for access types is having the same
5645 -- constant modifier.
5647 elsif Access_Types_Match
5648 and then Is_Access_Constant (Old_Formal_Base) /=
5649 Is_Access_Constant (New_Formal_Base)
5652 ("\constant modifier does not match!", New_Formal);
5657 if Ctype >= Subtype_Conformant then
5659 -- Ada 2005 (AI-231): In case of anonymous access types check
5660 -- the null-exclusion and access-to-constant attributes must
5661 -- match. For null exclusion, we test the types rather than the
5662 -- formals themselves, since the attribute is only set reliably
5663 -- on the formals in the Ada 95 case, and we exclude the case
5664 -- where Old_Formal is marked as controlling, to avoid errors
5665 -- when matching completing bodies with dispatching declarations
5666 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5668 if Ada_Version >= Ada_2005
5669 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5670 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5672 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5673 Can_Never_Be_Null (Etype (New_Formal))
5675 not Is_Controlling_Formal (Old_Formal))
5677 Is_Access_Constant (Etype (Old_Formal)) /=
5678 Is_Access_Constant (Etype (New_Formal)))
5680 -- Do not complain if error already posted on New_Formal. This
5681 -- avoids some redundant error messages.
5683 and then not Error_Posted (New_Formal)
5685 -- It is allowed to omit the null-exclusion in case of stream
5686 -- attribute subprograms. We recognize stream subprograms
5687 -- through their TSS-generated suffix.
5690 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5693 if TSS_Name /= TSS_Stream_Read
5694 and then TSS_Name /= TSS_Stream_Write
5695 and then TSS_Name /= TSS_Stream_Input
5696 and then TSS_Name /= TSS_Stream_Output
5698 -- Here we have a definite conformance error. It is worth
5699 -- special casing the error message for the case of a
5700 -- controlling formal (which excludes null).
5702 if Is_Controlling_Formal (New_Formal) then
5703 Error_Msg_Node_2 := Scope (New_Formal);
5705 ("\controlling formal & of & excludes null, "
5706 & "declaration must exclude null as well",
5709 -- Normal case (couldn't we give more detail here???)
5713 ("\type of & does not match!", New_Formal);
5722 -- Full conformance checks
5724 if Ctype = Fully_Conformant then
5726 -- We have checked already that names match
5728 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5730 -- Check default expressions for in parameters
5733 NewD : constant Boolean :=
5734 Present (Default_Value (New_Formal));
5735 OldD : constant Boolean :=
5736 Present (Default_Value (Old_Formal));
5738 if NewD or OldD then
5740 -- The old default value has been analyzed because the
5741 -- current full declaration will have frozen everything
5742 -- before. The new default value has not been analyzed,
5743 -- so analyze it now before we check for conformance.
5746 Push_Scope (New_Id);
5747 Preanalyze_Spec_Expression
5748 (Default_Value (New_Formal), Etype (New_Formal));
5752 if not (NewD and OldD)
5753 or else not Fully_Conformant_Expressions
5754 (Default_Value (Old_Formal),
5755 Default_Value (New_Formal))
5758 ("\default expression for & does not match!",
5767 -- A couple of special checks for Ada 83 mode. These checks are
5768 -- skipped if either entity is an operator in package Standard,
5769 -- or if either old or new instance is not from the source program.
5771 if Ada_Version = Ada_83
5772 and then Sloc (Old_Id) > Standard_Location
5773 and then Sloc (New_Id) > Standard_Location
5774 and then Comes_From_Source (Old_Id)
5775 and then Comes_From_Source (New_Id)
5778 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5779 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5782 -- Explicit IN must be present or absent in both cases. This
5783 -- test is required only in the full conformance case.
5785 if In_Present (Old_Param) /= In_Present (New_Param)
5786 and then Ctype = Fully_Conformant
5789 ("\(Ada 83) IN must appear in both declarations",
5794 -- Grouping (use of comma in param lists) must be the same
5795 -- This is where we catch a misconformance like:
5798 -- A : Integer; B : Integer
5800 -- which are represented identically in the tree except
5801 -- for the setting of the flags More_Ids and Prev_Ids.
5803 if More_Ids (Old_Param) /= More_Ids (New_Param)
5804 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5807 ("\grouping of & does not match!", New_Formal);
5813 -- This label is required when skipping controlling formals
5815 <<Skip_Controlling_Formal>>
5817 Next_Formal (Old_Formal);
5818 Next_Formal (New_Formal);
5821 if Present (Old_Formal) then
5822 Conformance_Error ("\too few parameters!");
5825 elsif Present (New_Formal) then
5826 Conformance_Error ("\too many parameters!", New_Formal);
5829 end Check_Conformance;
5831 -----------------------
5832 -- Check_Conventions --
5833 -----------------------
5835 procedure Check_Conventions (Typ : Entity_Id) is
5836 Ifaces_List : Elist_Id;
5838 procedure Check_Convention (Op : Entity_Id);
5839 -- Verify that the convention of inherited dispatching operation Op is
5840 -- consistent among all subprograms it overrides. In order to minimize
5841 -- the search, Search_From is utilized to designate a specific point in
5842 -- the list rather than iterating over the whole list once more.
5844 ----------------------
5845 -- Check_Convention --
5846 ----------------------
5848 procedure Check_Convention (Op : Entity_Id) is
5849 Op_Conv : constant Convention_Id := Convention (Op);
5850 Iface_Conv : Convention_Id;
5851 Iface_Elmt : Elmt_Id;
5852 Iface_Prim_Elmt : Elmt_Id;
5853 Iface_Prim : Entity_Id;
5856 Iface_Elmt := First_Elmt (Ifaces_List);
5857 while Present (Iface_Elmt) loop
5859 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5860 while Present (Iface_Prim_Elmt) loop
5861 Iface_Prim := Node (Iface_Prim_Elmt);
5862 Iface_Conv := Convention (Iface_Prim);
5864 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5865 and then Iface_Conv /= Op_Conv
5868 ("inconsistent conventions in primitive operations", Typ);
5870 Error_Msg_Name_1 := Chars (Op);
5871 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5872 Error_Msg_Sloc := Sloc (Op);
5874 if Comes_From_Source (Op) or else No (Alias (Op)) then
5875 if not Present (Overridden_Operation (Op)) then
5876 Error_Msg_N ("\\primitive % defined #", Typ);
5879 ("\\overriding operation % with "
5880 & "convention % defined #", Typ);
5883 else pragma Assert (Present (Alias (Op)));
5884 Error_Msg_Sloc := Sloc (Alias (Op));
5885 Error_Msg_N ("\\inherited operation % with "
5886 & "convention % defined #", Typ);
5889 Error_Msg_Name_1 := Chars (Op);
5890 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5891 Error_Msg_Sloc := Sloc (Iface_Prim);
5892 Error_Msg_N ("\\overridden operation % with "
5893 & "convention % defined #", Typ);
5895 -- Avoid cascading errors
5900 Next_Elmt (Iface_Prim_Elmt);
5903 Next_Elmt (Iface_Elmt);
5905 end Check_Convention;
5909 Prim_Op : Entity_Id;
5910 Prim_Op_Elmt : Elmt_Id;
5912 -- Start of processing for Check_Conventions
5915 if not Has_Interfaces (Typ) then
5919 Collect_Interfaces (Typ, Ifaces_List);
5921 -- The algorithm checks every overriding dispatching operation against
5922 -- all the corresponding overridden dispatching operations, detecting
5923 -- differences in conventions.
5925 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5926 while Present (Prim_Op_Elmt) loop
5927 Prim_Op := Node (Prim_Op_Elmt);
5929 -- A small optimization: skip the predefined dispatching operations
5930 -- since they always have the same convention.
5932 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5933 Check_Convention (Prim_Op);
5936 Next_Elmt (Prim_Op_Elmt);
5938 end Check_Conventions;
5940 ------------------------------
5941 -- Check_Delayed_Subprogram --
5942 ------------------------------
5944 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5945 procedure Possible_Freeze (T : Entity_Id);
5946 -- T is the type of either a formal parameter or of the return type. If
5947 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5948 -- itself must be delayed.
5950 ---------------------
5951 -- Possible_Freeze --
5952 ---------------------
5954 procedure Possible_Freeze (T : Entity_Id) is
5955 Scop : constant Entity_Id := Scope (Designator);
5958 -- If the subprogram appears within a package instance (which may be
5959 -- the wrapper package of a subprogram instance) the freeze node for
5960 -- that package will freeze the subprogram at the proper place, so
5961 -- do not emit a freeze node for the subprogram, given that it may
5962 -- appear in the wrong scope.
5964 if Ekind (Scop) = E_Package
5965 and then not Comes_From_Source (Scop)
5966 and then Is_Generic_Instance (Scop)
5970 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5971 Set_Has_Delayed_Freeze (Designator);
5973 elsif Is_Access_Type (T)
5974 and then Has_Delayed_Freeze (Designated_Type (T))
5975 and then not Is_Frozen (Designated_Type (T))
5977 Set_Has_Delayed_Freeze (Designator);
5979 end Possible_Freeze;
5985 -- Start of processing for Check_Delayed_Subprogram
5988 -- All subprograms, including abstract subprograms, may need a freeze
5989 -- node if some formal type or the return type needs one.
5991 Possible_Freeze (Etype (Designator));
5992 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5994 -- Need delayed freeze if any of the formal types themselves need a
5995 -- delayed freeze and are not yet frozen.
5997 F := First_Formal (Designator);
5998 while Present (F) loop
5999 Possible_Freeze (Etype (F));
6000 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
6004 -- Mark functions that return by reference. Note that it cannot be done
6005 -- for delayed_freeze subprograms because the underlying returned type
6006 -- may not be known yet (for private types).
6008 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
6010 Typ : constant Entity_Id := Etype (Designator);
6011 Utyp : constant Entity_Id := Underlying_Type (Typ);
6014 if Is_Limited_View (Typ) then
6015 Set_Returns_By_Ref (Designator);
6017 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
6018 Set_Returns_By_Ref (Designator);
6022 end Check_Delayed_Subprogram;
6024 ------------------------------------
6025 -- Check_Discriminant_Conformance --
6026 ------------------------------------
6028 procedure Check_Discriminant_Conformance
6033 Old_Discr : Entity_Id := First_Discriminant (Prev);
6034 New_Discr : Node_Id := First (Discriminant_Specifications (N));
6035 New_Discr_Id : Entity_Id;
6036 New_Discr_Type : Entity_Id;
6038 procedure Conformance_Error (Msg : String; N : Node_Id);
6039 -- Post error message for conformance error on given node. Two messages
6040 -- are output. The first points to the previous declaration with a
6041 -- general "no conformance" message. The second is the detailed reason,
6042 -- supplied as Msg. The parameter N provide information for a possible
6043 -- & insertion in the message.
6045 -----------------------
6046 -- Conformance_Error --
6047 -----------------------
6049 procedure Conformance_Error (Msg : String; N : Node_Id) is
6051 Error_Msg_Sloc := Sloc (Prev_Loc);
6052 Error_Msg_N -- CODEFIX
6053 ("not fully conformant with declaration#!", N);
6054 Error_Msg_NE (Msg, N, N);
6055 end Conformance_Error;
6057 -- Start of processing for Check_Discriminant_Conformance
6060 while Present (Old_Discr) and then Present (New_Discr) loop
6061 New_Discr_Id := Defining_Identifier (New_Discr);
6063 -- The subtype mark of the discriminant on the full type has not
6064 -- been analyzed so we do it here. For an access discriminant a new
6067 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
6069 Access_Definition (N, Discriminant_Type (New_Discr));
6072 Analyze (Discriminant_Type (New_Discr));
6073 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6075 -- Ada 2005: if the discriminant definition carries a null
6076 -- exclusion, create an itype to check properly for consistency
6077 -- with partial declaration.
6079 if Is_Access_Type (New_Discr_Type)
6080 and then Null_Exclusion_Present (New_Discr)
6083 Create_Null_Excluding_Itype
6084 (T => New_Discr_Type,
6085 Related_Nod => New_Discr,
6086 Scope_Id => Current_Scope);
6090 if not Conforming_Types
6091 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6093 Conformance_Error ("type of & does not match!", New_Discr_Id);
6096 -- Treat the new discriminant as an occurrence of the old one,
6097 -- for navigation purposes, and fill in some semantic
6098 -- information, for completeness.
6100 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6101 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6102 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6107 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6108 Conformance_Error ("name & does not match!", New_Discr_Id);
6112 -- Default expressions must match
6115 NewD : constant Boolean :=
6116 Present (Expression (New_Discr));
6117 OldD : constant Boolean :=
6118 Present (Expression (Parent (Old_Discr)));
6121 if NewD or OldD then
6123 -- The old default value has been analyzed and expanded,
6124 -- because the current full declaration will have frozen
6125 -- everything before. The new default values have not been
6126 -- expanded, so expand now to check conformance.
6129 Preanalyze_Spec_Expression
6130 (Expression (New_Discr), New_Discr_Type);
6133 if not (NewD and OldD)
6134 or else not Fully_Conformant_Expressions
6135 (Expression (Parent (Old_Discr)),
6136 Expression (New_Discr))
6140 ("default expression for & does not match!",
6147 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6149 if Ada_Version = Ada_83 then
6151 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6154 -- Grouping (use of comma in param lists) must be the same
6155 -- This is where we catch a misconformance like:
6158 -- A : Integer; B : Integer
6160 -- which are represented identically in the tree except
6161 -- for the setting of the flags More_Ids and Prev_Ids.
6163 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6164 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6167 ("grouping of & does not match!", New_Discr_Id);
6173 Next_Discriminant (Old_Discr);
6177 if Present (Old_Discr) then
6178 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6181 elsif Present (New_Discr) then
6183 ("too many discriminants!", Defining_Identifier (New_Discr));
6186 end Check_Discriminant_Conformance;
6188 ----------------------------
6189 -- Check_Fully_Conformant --
6190 ----------------------------
6192 procedure Check_Fully_Conformant
6193 (New_Id : Entity_Id;
6195 Err_Loc : Node_Id := Empty)
6198 pragma Warnings (Off, Result);
6201 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6202 end Check_Fully_Conformant;
6204 --------------------------
6205 -- Check_Limited_Return --
6206 --------------------------
6208 procedure Check_Limited_Return
6214 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6215 -- replaced by anonymous access results. This is an incompatibility with
6216 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6217 -- controllable with special switch. ???
6219 -- A limited interface that is not immutably limited is OK
6221 if Is_Limited_Interface (R_Type)
6223 not (Is_Task_Interface (R_Type)
6224 or else Is_Protected_Interface (R_Type)
6225 or else Is_Synchronized_Interface (R_Type))
6229 elsif Is_Limited_Type (R_Type)
6230 and then not Is_Interface (R_Type)
6231 and then Comes_From_Source (N)
6232 and then not In_Instance_Body
6233 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6235 -- Error in Ada 2005
6237 if Ada_Version >= Ada_2005
6238 and then not Debug_Flag_Dot_L
6239 and then not GNAT_Mode
6242 ("(Ada 2005) cannot copy object of a limited type "
6243 & "(RM-2005 6.5(5.5/2))", Expr);
6245 if Is_Limited_View (R_Type) then
6247 ("\return by reference not permitted in Ada 2005", Expr);
6250 -- Warn in Ada 95 mode, to give folks a heads up about this
6253 -- In GNAT mode, this is just a warning, to allow it to be evilly
6254 -- turned off. Otherwise it is a real error.
6256 -- In a generic context, simplify the warning because it makes no
6257 -- sense to discuss pass-by-reference or copy.
6259 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6260 if Inside_A_Generic then
6262 ("return of limited object not permitted in Ada 2005 "
6263 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6265 elsif Is_Limited_View (R_Type) then
6267 ("return by reference not permitted in Ada 2005 "
6268 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6271 ("cannot copy object of a limited type in Ada 2005 "
6272 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6275 -- Ada 95 mode, and compatibility warnings disabled
6278 pragma Assert (Ada_Version <= Ada_95);
6279 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6280 return; -- skip continuation messages below
6283 if not Inside_A_Generic then
6285 ("\consider switching to return of access type", Expr);
6286 Explain_Limited_Type (R_Type, Expr);
6289 end Check_Limited_Return;
6291 ---------------------------
6292 -- Check_Mode_Conformant --
6293 ---------------------------
6295 procedure Check_Mode_Conformant
6296 (New_Id : Entity_Id;
6298 Err_Loc : Node_Id := Empty;
6299 Get_Inst : Boolean := False)
6302 pragma Warnings (Off, Result);
6305 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6306 end Check_Mode_Conformant;
6308 --------------------------------
6309 -- Check_Overriding_Indicator --
6310 --------------------------------
6312 procedure Check_Overriding_Indicator
6314 Overridden_Subp : Entity_Id;
6315 Is_Primitive : Boolean)
6321 -- No overriding indicator for literals
6323 if Ekind (Subp) = E_Enumeration_Literal then
6326 elsif Ekind (Subp) = E_Entry then
6327 Decl := Parent (Subp);
6329 -- No point in analyzing a malformed operator
6331 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6332 and then Error_Posted (Subp)
6337 Decl := Unit_Declaration_Node (Subp);
6340 if Nkind_In (Decl, N_Subprogram_Body,
6341 N_Subprogram_Body_Stub,
6342 N_Subprogram_Declaration,
6343 N_Abstract_Subprogram_Declaration,
6344 N_Subprogram_Renaming_Declaration)
6346 Spec := Specification (Decl);
6348 elsif Nkind (Decl) = N_Entry_Declaration then
6355 -- The overriding operation is type conformant with the overridden one,
6356 -- but the names of the formals are not required to match. If the names
6357 -- appear permuted in the overriding operation, this is a possible
6358 -- source of confusion that is worth diagnosing. Controlling formals
6359 -- often carry names that reflect the type, and it is not worthwhile
6360 -- requiring that their names match.
6362 if Present (Overridden_Subp)
6363 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6370 Form1 := First_Formal (Subp);
6371 Form2 := First_Formal (Overridden_Subp);
6373 -- If the overriding operation is a synchronized operation, skip
6374 -- the first parameter of the overridden operation, which is
6375 -- implicit in the new one. If the operation is declared in the
6376 -- body it is not primitive and all formals must match.
6378 if Is_Concurrent_Type (Scope (Subp))
6379 and then Is_Tagged_Type (Scope (Subp))
6380 and then not Has_Completion (Scope (Subp))
6382 Form2 := Next_Formal (Form2);
6385 if Present (Form1) then
6386 Form1 := Next_Formal (Form1);
6387 Form2 := Next_Formal (Form2);
6390 while Present (Form1) loop
6391 if not Is_Controlling_Formal (Form1)
6392 and then Present (Next_Formal (Form2))
6393 and then Chars (Form1) = Chars (Next_Formal (Form2))
6395 Error_Msg_Node_2 := Alias (Overridden_Subp);
6396 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6398 ("& does not match corresponding formal of&#",
6403 Next_Formal (Form1);
6404 Next_Formal (Form2);
6409 -- If there is an overridden subprogram, then check that there is no
6410 -- "not overriding" indicator, and mark the subprogram as overriding.
6411 -- This is not done if the overridden subprogram is marked as hidden,
6412 -- which can occur for the case of inherited controlled operations
6413 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6414 -- subprogram is not itself hidden. (Note: This condition could probably
6415 -- be simplified, leaving out the testing for the specific controlled
6416 -- cases, but it seems safer and clearer this way, and echoes similar
6417 -- special-case tests of this kind in other places.)
6419 if Present (Overridden_Subp)
6420 and then (not Is_Hidden (Overridden_Subp)
6422 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6425 and then Present (Alias (Overridden_Subp))
6426 and then not Is_Hidden (Alias (Overridden_Subp))))
6428 if Must_Not_Override (Spec) then
6429 Error_Msg_Sloc := Sloc (Overridden_Subp);
6431 if Ekind (Subp) = E_Entry then
6433 ("entry & overrides inherited operation #", Spec, Subp);
6436 ("subprogram & overrides inherited operation #", Spec, Subp);
6439 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6440 -- as an extension of Root_Controlled, and thus has a useless Adjust
6441 -- operation. This operation should not be inherited by other limited
6442 -- controlled types. An explicit Adjust for them is not overriding.
6444 elsif Must_Override (Spec)
6445 and then Chars (Overridden_Subp) = Name_Adjust
6446 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6447 and then Present (Alias (Overridden_Subp))
6448 and then In_Predefined_Unit (Alias (Overridden_Subp))
6451 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6452 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6454 elsif Is_Subprogram (Subp) then
6455 if Is_Init_Proc (Subp) then
6458 elsif No (Overridden_Operation (Subp)) then
6460 -- For entities generated by Derive_Subprograms the overridden
6461 -- operation is the inherited primitive (which is available
6462 -- through the attribute alias)
6464 if (Is_Dispatching_Operation (Subp)
6465 or else Is_Dispatching_Operation (Overridden_Subp))
6466 and then not Comes_From_Source (Overridden_Subp)
6467 and then Find_Dispatching_Type (Overridden_Subp) =
6468 Find_Dispatching_Type (Subp)
6469 and then Present (Alias (Overridden_Subp))
6470 and then Comes_From_Source (Alias (Overridden_Subp))
6472 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6473 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6476 Set_Overridden_Operation (Subp, Overridden_Subp);
6477 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6482 -- If primitive flag is set or this is a protected operation, then
6483 -- the operation is overriding at the point of its declaration, so
6484 -- warn if necessary. Otherwise it may have been declared before the
6485 -- operation it overrides and no check is required.
6488 and then not Must_Override (Spec)
6489 and then (Is_Primitive
6490 or else Ekind (Scope (Subp)) = E_Protected_Type)
6492 Style.Missing_Overriding (Decl, Subp);
6495 -- If Subp is an operator, it may override a predefined operation, if
6496 -- it is defined in the same scope as the type to which it applies.
6497 -- In that case Overridden_Subp is empty because of our implicit
6498 -- representation for predefined operators. We have to check whether the
6499 -- signature of Subp matches that of a predefined operator. Note that
6500 -- first argument provides the name of the operator, and the second
6501 -- argument the signature that may match that of a standard operation.
6502 -- If the indicator is overriding, then the operator must match a
6503 -- predefined signature, because we know already that there is no
6504 -- explicit overridden operation.
6506 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6507 if Must_Not_Override (Spec) then
6509 -- If this is not a primitive or a protected subprogram, then
6510 -- "not overriding" is illegal.
6513 and then Ekind (Scope (Subp)) /= E_Protected_Type
6515 Error_Msg_N ("overriding indicator only allowed "
6516 & "if subprogram is primitive", Subp);
6518 elsif Can_Override_Operator (Subp) then
6520 ("subprogram& overrides predefined operator ", Spec, Subp);
6523 elsif Must_Override (Spec) then
6524 if No (Overridden_Operation (Subp))
6525 and then not Can_Override_Operator (Subp)
6527 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6530 elsif not Error_Posted (Subp)
6531 and then Style_Check
6532 and then Can_Override_Operator (Subp)
6533 and then not In_Predefined_Unit (Subp)
6535 -- If style checks are enabled, indicate that the indicator is
6536 -- missing. However, at the point of declaration, the type of
6537 -- which this is a primitive operation may be private, in which
6538 -- case the indicator would be premature.
6540 if Has_Private_Declaration (Etype (Subp))
6541 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6545 Style.Missing_Overriding (Decl, Subp);
6549 elsif Must_Override (Spec) then
6550 if Ekind (Subp) = E_Entry then
6551 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6553 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6556 -- If the operation is marked "not overriding" and it's not primitive
6557 -- then an error is issued, unless this is an operation of a task or
6558 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6559 -- has been specified have already been checked above.
6561 elsif Must_Not_Override (Spec)
6562 and then not Is_Primitive
6563 and then Ekind (Subp) /= E_Entry
6564 and then Ekind (Scope (Subp)) /= E_Protected_Type
6567 ("overriding indicator only allowed if subprogram is primitive",
6571 end Check_Overriding_Indicator;
6577 -- Note: this procedure needs to know far too much about how the expander
6578 -- messes with exceptions. The use of the flag Exception_Junk and the
6579 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6580 -- works, but is not very clean. It would be better if the expansion
6581 -- routines would leave Original_Node working nicely, and we could use
6582 -- Original_Node here to ignore all the peculiar expander messing ???
6584 procedure Check_Returns
6588 Proc : Entity_Id := Empty)
6592 procedure Check_Statement_Sequence (L : List_Id);
6593 -- Internal recursive procedure to check a list of statements for proper
6594 -- termination by a return statement (or a transfer of control or a
6595 -- compound statement that is itself internally properly terminated).
6597 ------------------------------
6598 -- Check_Statement_Sequence --
6599 ------------------------------
6601 procedure Check_Statement_Sequence (L : List_Id) is
6606 function Assert_False return Boolean;
6607 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6608 -- rewritten as a null statement when assertions are off. The assert
6609 -- is not active, but it is still enough to kill the warning.
6615 function Assert_False return Boolean is
6616 Orig : constant Node_Id := Original_Node (Last_Stm);
6619 if Nkind (Orig) = N_Pragma
6620 and then Pragma_Name (Orig) = Name_Assert
6621 and then not Error_Posted (Orig)
6624 Arg : constant Node_Id :=
6625 First (Pragma_Argument_Associations (Orig));
6626 Exp : constant Node_Id := Expression (Arg);
6628 return Nkind (Exp) = N_Identifier
6629 and then Chars (Exp) = Name_False;
6639 Raise_Exception_Call : Boolean;
6640 -- Set True if statement sequence terminated by Raise_Exception call
6641 -- or a Reraise_Occurrence call.
6643 -- Start of processing for Check_Statement_Sequence
6646 Raise_Exception_Call := False;
6648 -- Get last real statement
6650 Last_Stm := Last (L);
6652 -- Deal with digging out exception handler statement sequences that
6653 -- have been transformed by the local raise to goto optimization.
6654 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6655 -- optimization has occurred, we are looking at something like:
6658 -- original stmts in block
6662 -- goto L1; | omitted if No_Exception_Propagation
6667 -- goto L3; -- skip handler when exception not raised
6669 -- <<L1>> -- target label for local exception
6683 -- and what we have to do is to dig out the estmts1 and estmts2
6684 -- sequences (which were the original sequences of statements in
6685 -- the exception handlers) and check them.
6687 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6692 exit when Nkind (Stm) /= N_Block_Statement;
6693 exit when not Exception_Junk (Stm);
6696 exit when Nkind (Stm) /= N_Label;
6697 exit when not Exception_Junk (Stm);
6698 Check_Statement_Sequence
6699 (Statements (Handled_Statement_Sequence (Next (Stm))));
6704 exit when Nkind (Stm) /= N_Goto_Statement;
6705 exit when not Exception_Junk (Stm);
6709 -- Don't count pragmas
6711 while Nkind (Last_Stm) = N_Pragma
6713 -- Don't count call to SS_Release (can happen after Raise_Exception)
6716 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6718 Nkind (Name (Last_Stm)) = N_Identifier
6720 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6722 -- Don't count exception junk
6725 (Nkind_In (Last_Stm, N_Goto_Statement,
6727 N_Object_Declaration)
6728 and then Exception_Junk (Last_Stm))
6729 or else Nkind (Last_Stm) in N_Push_xxx_Label
6730 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6732 -- Inserted code, such as finalization calls, is irrelevant: we only
6733 -- need to check original source.
6735 or else Is_Rewrite_Insertion (Last_Stm)
6740 -- Here we have the "real" last statement
6742 Kind := Nkind (Last_Stm);
6744 -- Transfer of control, OK. Note that in the No_Return procedure
6745 -- case, we already diagnosed any explicit return statements, so
6746 -- we can treat them as OK in this context.
6748 if Is_Transfer (Last_Stm) then
6751 -- Check cases of explicit non-indirect procedure calls
6753 elsif Kind = N_Procedure_Call_Statement
6754 and then Is_Entity_Name (Name (Last_Stm))
6756 -- Check call to Raise_Exception procedure which is treated
6757 -- specially, as is a call to Reraise_Occurrence.
6759 -- We suppress the warning in these cases since it is likely that
6760 -- the programmer really does not expect to deal with the case
6761 -- of Null_Occurrence, and thus would find a warning about a
6762 -- missing return curious, and raising Program_Error does not
6763 -- seem such a bad behavior if this does occur.
6765 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6766 -- behavior will be to raise Constraint_Error (see AI-329).
6768 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6770 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6772 Raise_Exception_Call := True;
6774 -- For Raise_Exception call, test first argument, if it is
6775 -- an attribute reference for a 'Identity call, then we know
6776 -- that the call cannot possibly return.
6779 Arg : constant Node_Id :=
6780 Original_Node (First_Actual (Last_Stm));
6782 if Nkind (Arg) = N_Attribute_Reference
6783 and then Attribute_Name (Arg) = Name_Identity
6790 -- If statement, need to look inside if there is an else and check
6791 -- each constituent statement sequence for proper termination.
6793 elsif Kind = N_If_Statement
6794 and then Present (Else_Statements (Last_Stm))
6796 Check_Statement_Sequence (Then_Statements (Last_Stm));
6797 Check_Statement_Sequence (Else_Statements (Last_Stm));
6799 if Present (Elsif_Parts (Last_Stm)) then
6801 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6804 while Present (Elsif_Part) loop
6805 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6813 -- Case statement, check each case for proper termination
6815 elsif Kind = N_Case_Statement then
6819 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6820 while Present (Case_Alt) loop
6821 Check_Statement_Sequence (Statements (Case_Alt));
6822 Next_Non_Pragma (Case_Alt);
6828 -- Block statement, check its handled sequence of statements
6830 elsif Kind = N_Block_Statement then
6836 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6845 -- Loop statement. If there is an iteration scheme, we can definitely
6846 -- fall out of the loop. Similarly if there is an exit statement, we
6847 -- can fall out. In either case we need a following return.
6849 elsif Kind = N_Loop_Statement then
6850 if Present (Iteration_Scheme (Last_Stm))
6851 or else Has_Exit (Entity (Identifier (Last_Stm)))
6855 -- A loop with no exit statement or iteration scheme is either
6856 -- an infinite loop, or it has some other exit (raise/return).
6857 -- In either case, no warning is required.
6863 -- Timed entry call, check entry call and delay alternatives
6865 -- Note: in expanded code, the timed entry call has been converted
6866 -- to a set of expanded statements on which the check will work
6867 -- correctly in any case.
6869 elsif Kind = N_Timed_Entry_Call then
6871 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6872 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6875 -- If statement sequence of entry call alternative is missing,
6876 -- then we can definitely fall through, and we post the error
6877 -- message on the entry call alternative itself.
6879 if No (Statements (ECA)) then
6882 -- If statement sequence of delay alternative is missing, then
6883 -- we can definitely fall through, and we post the error
6884 -- message on the delay alternative itself.
6886 -- Note: if both ECA and DCA are missing the return, then we
6887 -- post only one message, should be enough to fix the bugs.
6888 -- If not we will get a message next time on the DCA when the
6891 elsif No (Statements (DCA)) then
6894 -- Else check both statement sequences
6897 Check_Statement_Sequence (Statements (ECA));
6898 Check_Statement_Sequence (Statements (DCA));
6903 -- Conditional entry call, check entry call and else part
6905 -- Note: in expanded code, the conditional entry call has been
6906 -- converted to a set of expanded statements on which the check
6907 -- will work correctly in any case.
6909 elsif Kind = N_Conditional_Entry_Call then
6911 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6914 -- If statement sequence of entry call alternative is missing,
6915 -- then we can definitely fall through, and we post the error
6916 -- message on the entry call alternative itself.
6918 if No (Statements (ECA)) then
6921 -- Else check statement sequence and else part
6924 Check_Statement_Sequence (Statements (ECA));
6925 Check_Statement_Sequence (Else_Statements (Last_Stm));
6931 -- If we fall through, issue appropriate message
6935 -- Kill warning if last statement is a raise exception call,
6936 -- or a pragma Assert (False). Note that with assertions enabled,
6937 -- such a pragma has been converted into a raise exception call
6938 -- already, so the Assert_False is for the assertions off case.
6940 if not Raise_Exception_Call and then not Assert_False then
6942 -- In GNATprove mode, it is an error to have a missing return
6944 Error_Msg_Warn := SPARK_Mode /= On;
6946 -- Issue error message or warning
6949 ("RETURN statement missing following this statement<<!",
6952 ("\Program_Error ]<<!", Last_Stm);
6955 -- Note: we set Err even though we have not issued a warning
6956 -- because we still have a case of a missing return. This is
6957 -- an extremely marginal case, probably will never be noticed
6958 -- but we might as well get it right.
6962 -- Otherwise we have the case of a procedure marked No_Return
6965 if not Raise_Exception_Call then
6966 if GNATprove_Mode then
6968 ("implied return after this statement would have raised "
6969 & "Program_Error", Last_Stm);
6971 -- In normal compilation mode, do not warn on a generated call
6972 -- (e.g. in the body of a renaming as completion).
6974 elsif Comes_From_Source (Last_Stm) then
6976 ("implied return after this statement will raise "
6977 & "Program_Error??", Last_Stm);
6980 Error_Msg_Warn := SPARK_Mode /= On;
6982 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6986 RE : constant Node_Id :=
6987 Make_Raise_Program_Error (Sloc (Last_Stm),
6988 Reason => PE_Implicit_Return);
6990 Insert_After (Last_Stm, RE);
6994 end Check_Statement_Sequence;
6996 -- Start of processing for Check_Returns
7000 Check_Statement_Sequence (Statements (HSS));
7002 if Present (Exception_Handlers (HSS)) then
7003 Handler := First_Non_Pragma (Exception_Handlers (HSS));
7004 while Present (Handler) loop
7005 Check_Statement_Sequence (Statements (Handler));
7006 Next_Non_Pragma (Handler);
7011 ----------------------------
7012 -- Check_Subprogram_Order --
7013 ----------------------------
7015 procedure Check_Subprogram_Order (N : Node_Id) is
7017 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
7018 -- This is used to check if S1 > S2 in the sense required by this test,
7019 -- for example nameab < namec, but name2 < name10.
7021 -----------------------------
7022 -- Subprogram_Name_Greater --
7023 -----------------------------
7025 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
7030 -- Deal with special case where names are identical except for a
7031 -- numerical suffix. These are handled specially, taking the numeric
7032 -- ordering from the suffix into account.
7035 while S1 (L1) in '0' .. '9' loop
7040 while S2 (L2) in '0' .. '9' loop
7044 -- If non-numeric parts non-equal, do straight compare
7046 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
7049 -- If non-numeric parts equal, compare suffixed numeric parts. Note
7050 -- that a missing suffix is treated as numeric zero in this test.
7054 while L1 < S1'Last loop
7056 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
7060 while L2 < S2'Last loop
7062 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
7067 end Subprogram_Name_Greater;
7069 -- Start of processing for Check_Subprogram_Order
7072 -- Check body in alpha order if this is option
7075 and then Style_Check_Order_Subprograms
7076 and then Nkind (N) = N_Subprogram_Body
7077 and then Comes_From_Source (N)
7078 and then In_Extended_Main_Source_Unit (N)
7082 renames Scope_Stack.Table
7083 (Scope_Stack.Last).Last_Subprogram_Name;
7085 Body_Id : constant Entity_Id :=
7086 Defining_Entity (Specification (N));
7089 Get_Decoded_Name_String (Chars (Body_Id));
7092 if Subprogram_Name_Greater
7093 (LSN.all, Name_Buffer (1 .. Name_Len))
7095 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7101 LSN := new String'(Name_Buffer (1 .. Name_Len));
7104 end Check_Subprogram_Order;
7106 ------------------------------
7107 -- Check_Subtype_Conformant --
7108 ------------------------------
7110 procedure Check_Subtype_Conformant
7111 (New_Id : Entity_Id;
7113 Err_Loc : Node_Id := Empty;
7114 Skip_Controlling_Formals : Boolean := False;
7115 Get_Inst : Boolean := False)
7118 pragma Warnings (Off, Result);
7121 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7122 Skip_Controlling_Formals => Skip_Controlling_Formals,
7123 Get_Inst => Get_Inst);
7124 end Check_Subtype_Conformant;
7126 -----------------------------------
7127 -- Check_Synchronized_Overriding --
7128 -----------------------------------
7130 procedure Check_Synchronized_Overriding
7131 (Def_Id : Entity_Id;
7132 Overridden_Subp : out Entity_Id)
7134 Ifaces_List : Elist_Id;
7138 function Matches_Prefixed_View_Profile
7139 (Prim_Params : List_Id;
7140 Iface_Params : List_Id) return Boolean;
7141 -- Determine whether a subprogram's parameter profile Prim_Params
7142 -- matches that of a potentially overridden interface subprogram
7143 -- Iface_Params. Also determine if the type of first parameter of
7144 -- Iface_Params is an implemented interface.
7146 -----------------------------------
7147 -- Matches_Prefixed_View_Profile --
7148 -----------------------------------
7150 function Matches_Prefixed_View_Profile
7151 (Prim_Params : List_Id;
7152 Iface_Params : List_Id) return Boolean
7154 function Is_Implemented
7155 (Ifaces_List : Elist_Id;
7156 Iface : Entity_Id) return Boolean;
7157 -- Determine if Iface is implemented by the current task or
7160 --------------------
7161 -- Is_Implemented --
7162 --------------------
7164 function Is_Implemented
7165 (Ifaces_List : Elist_Id;
7166 Iface : Entity_Id) return Boolean
7168 Iface_Elmt : Elmt_Id;
7171 Iface_Elmt := First_Elmt (Ifaces_List);
7172 while Present (Iface_Elmt) loop
7173 if Node (Iface_Elmt) = Iface then
7177 Next_Elmt (Iface_Elmt);
7185 Iface_Id : Entity_Id;
7186 Iface_Param : Node_Id;
7187 Iface_Typ : Entity_Id;
7188 Prim_Id : Entity_Id;
7189 Prim_Param : Node_Id;
7190 Prim_Typ : Entity_Id;
7192 -- Start of processing for Matches_Prefixed_View_Profile
7195 Iface_Param := First (Iface_Params);
7196 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7198 if Is_Access_Type (Iface_Typ) then
7199 Iface_Typ := Designated_Type (Iface_Typ);
7202 Prim_Param := First (Prim_Params);
7204 -- The first parameter of the potentially overridden subprogram must
7205 -- be an interface implemented by Prim.
7207 if not Is_Interface (Iface_Typ)
7208 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7213 -- The checks on the object parameters are done, so move on to the
7214 -- rest of the parameters.
7216 if not In_Scope then
7217 Prim_Param := Next (Prim_Param);
7220 Iface_Param := Next (Iface_Param);
7221 while Present (Iface_Param) and then Present (Prim_Param) loop
7222 Iface_Id := Defining_Identifier (Iface_Param);
7223 Iface_Typ := Find_Parameter_Type (Iface_Param);
7225 Prim_Id := Defining_Identifier (Prim_Param);
7226 Prim_Typ := Find_Parameter_Type (Prim_Param);
7228 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7229 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7230 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7232 Iface_Typ := Designated_Type (Iface_Typ);
7233 Prim_Typ := Designated_Type (Prim_Typ);
7236 -- Case of multiple interface types inside a parameter profile
7238 -- (Obj_Param : in out Iface; ...; Param : Iface)
7240 -- If the interface type is implemented, then the matching type in
7241 -- the primitive should be the implementing record type.
7243 if Ekind (Iface_Typ) = E_Record_Type
7244 and then Is_Interface (Iface_Typ)
7245 and then Is_Implemented (Ifaces_List, Iface_Typ)
7247 if Prim_Typ /= Typ then
7251 -- The two parameters must be both mode and subtype conformant
7253 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7255 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7264 -- One of the two lists contains more parameters than the other
7266 if Present (Iface_Param) or else Present (Prim_Param) then
7271 end Matches_Prefixed_View_Profile;
7273 -- Start of processing for Check_Synchronized_Overriding
7276 Overridden_Subp := Empty;
7278 -- Def_Id must be an entry or a subprogram. We should skip predefined
7279 -- primitives internally generated by the front end; however at this
7280 -- stage predefined primitives are still not fully decorated. As a
7281 -- minor optimization we skip here internally generated subprograms.
7283 if (Ekind (Def_Id) /= E_Entry
7284 and then Ekind (Def_Id) /= E_Function
7285 and then Ekind (Def_Id) /= E_Procedure)
7286 or else not Comes_From_Source (Def_Id)
7291 -- Search for the concurrent declaration since it contains the list of
7292 -- all implemented interfaces. In this case, the subprogram is declared
7293 -- within the scope of a protected or a task type.
7295 if Present (Scope (Def_Id))
7296 and then Is_Concurrent_Type (Scope (Def_Id))
7297 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7299 Typ := Scope (Def_Id);
7302 -- The enclosing scope is not a synchronized type and the subprogram
7305 elsif No (First_Formal (Def_Id)) then
7308 -- The subprogram has formals and hence it may be a primitive of a
7312 Typ := Etype (First_Formal (Def_Id));
7314 if Is_Access_Type (Typ) then
7315 Typ := Directly_Designated_Type (Typ);
7318 if Is_Concurrent_Type (Typ)
7319 and then not Is_Generic_Actual_Type (Typ)
7323 -- This case occurs when the concurrent type is declared within a
7324 -- generic unit. As a result the corresponding record has been built
7325 -- and used as the type of the first formal, we just have to retrieve
7326 -- the corresponding concurrent type.
7328 elsif Is_Concurrent_Record_Type (Typ)
7329 and then not Is_Class_Wide_Type (Typ)
7330 and then Present (Corresponding_Concurrent_Type (Typ))
7332 Typ := Corresponding_Concurrent_Type (Typ);
7340 -- There is no overriding to check if this is an inherited operation in
7341 -- a type derivation for a generic actual.
7343 Collect_Interfaces (Typ, Ifaces_List);
7345 if Is_Empty_Elmt_List (Ifaces_List) then
7349 -- Determine whether entry or subprogram Def_Id overrides a primitive
7350 -- operation that belongs to one of the interfaces in Ifaces_List.
7353 Candidate : Entity_Id := Empty;
7354 Hom : Entity_Id := Empty;
7355 Subp : Entity_Id := Empty;
7358 -- Traverse the homonym chain, looking for a potentially overridden
7359 -- subprogram that belongs to an implemented interface.
7361 Hom := Current_Entity_In_Scope (Def_Id);
7362 while Present (Hom) loop
7366 or else not Is_Overloadable (Subp)
7367 or else not Is_Primitive (Subp)
7368 or else not Is_Dispatching_Operation (Subp)
7369 or else not Present (Find_Dispatching_Type (Subp))
7370 or else not Is_Interface (Find_Dispatching_Type (Subp))
7374 -- Entries and procedures can override abstract or null interface
7377 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7378 and then Ekind (Subp) = E_Procedure
7379 and then Matches_Prefixed_View_Profile
7380 (Parameter_Specifications (Parent (Def_Id)),
7381 Parameter_Specifications (Parent (Subp)))
7385 -- For an overridden subprogram Subp, check whether the mode
7386 -- of its first parameter is correct depending on the kind of
7387 -- synchronized type.
7390 Formal : constant Node_Id := First_Formal (Candidate);
7393 -- In order for an entry or a protected procedure to
7394 -- override, the first parameter of the overridden routine
7395 -- must be of mode "out", "in out", or access-to-variable.
7397 if Ekind_In (Candidate, E_Entry, E_Procedure)
7398 and then Is_Protected_Type (Typ)
7399 and then Ekind (Formal) /= E_In_Out_Parameter
7400 and then Ekind (Formal) /= E_Out_Parameter
7401 and then Nkind (Parameter_Type (Parent (Formal))) /=
7406 -- All other cases are OK since a task entry or routine does
7407 -- not have a restriction on the mode of the first parameter
7408 -- of the overridden interface routine.
7411 Overridden_Subp := Candidate;
7416 -- Functions can override abstract interface functions
7418 elsif Ekind (Def_Id) = E_Function
7419 and then Ekind (Subp) = E_Function
7420 and then Matches_Prefixed_View_Profile
7421 (Parameter_Specifications (Parent (Def_Id)),
7422 Parameter_Specifications (Parent (Subp)))
7423 and then Etype (Def_Id) = Etype (Subp)
7427 -- If an inherited subprogram is implemented by a protected
7428 -- function, then the first parameter of the inherited
7429 -- subprogram shall be of mode in, but not an access-to-
7430 -- variable parameter (RM 9.4(11/9)).
7432 if Present (First_Formal (Subp))
7433 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7435 (not Is_Access_Type (Etype (First_Formal (Subp)))
7437 Is_Access_Constant (Etype (First_Formal (Subp))))
7439 Overridden_Subp := Subp;
7444 Hom := Homonym (Hom);
7447 -- After examining all candidates for overriding, we are left with
7448 -- the best match, which is a mode-incompatible interface routine.
7450 if In_Scope and then Present (Candidate) then
7451 Error_Msg_PT (Def_Id, Candidate);
7454 Overridden_Subp := Candidate;
7457 end Check_Synchronized_Overriding;
7459 ---------------------------
7460 -- Check_Type_Conformant --
7461 ---------------------------
7463 procedure Check_Type_Conformant
7464 (New_Id : Entity_Id;
7466 Err_Loc : Node_Id := Empty)
7469 pragma Warnings (Off, Result);
7472 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7473 end Check_Type_Conformant;
7475 ---------------------------
7476 -- Can_Override_Operator --
7477 ---------------------------
7479 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7483 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7487 Typ := Base_Type (Etype (First_Formal (Subp)));
7489 -- Check explicitly that the operation is a primitive of the type
7491 return Operator_Matches_Spec (Subp, Subp)
7492 and then not Is_Generic_Type (Typ)
7493 and then Scope (Subp) = Scope (Typ)
7494 and then not Is_Class_Wide_Type (Typ);
7496 end Can_Override_Operator;
7498 ----------------------
7499 -- Conforming_Types --
7500 ----------------------
7502 function Conforming_Types
7505 Ctype : Conformance_Type;
7506 Get_Inst : Boolean := False) return Boolean
7508 function Base_Types_Match
7510 Typ_2 : Entity_Id) return Boolean;
7511 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7512 -- in different scopes (e.g. parent and child instances), then verify
7513 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7514 -- the same subtype chain. The whole purpose of this procedure is to
7515 -- prevent spurious ambiguities in an instantiation that may arise if
7516 -- two distinct generic types are instantiated with the same actual.
7518 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7519 -- An access parameter can designate an incomplete type. If the
7520 -- incomplete type is the limited view of a type from a limited_
7521 -- with_clause, check whether the non-limited view is available.
7522 -- If it is a (non-limited) incomplete type, get the full view.
7524 function Matches_Limited_With_View
7526 Typ_2 : Entity_Id) return Boolean;
7527 -- Returns True if and only if either Typ_1 denotes a limited view of
7528 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7529 -- the limited with view of a type is used in a subprogram declaration
7530 -- and the subprogram body is in the scope of a regular with clause for
7531 -- the same unit. In such a case, the two type entities are considered
7532 -- identical for purposes of conformance checking.
7534 ----------------------
7535 -- Base_Types_Match --
7536 ----------------------
7538 function Base_Types_Match
7540 Typ_2 : Entity_Id) return Boolean
7542 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7543 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7546 if Typ_1 = Typ_2 then
7549 elsif Base_1 = Base_2 then
7551 -- The following is too permissive. A more precise test should
7552 -- check that the generic actual is an ancestor subtype of the
7555 -- See code in Find_Corresponding_Spec that applies an additional
7556 -- filter to handle accidental amiguities in instances.
7559 not Is_Generic_Actual_Type (Typ_1)
7560 or else not Is_Generic_Actual_Type (Typ_2)
7561 or else Scope (Typ_1) /= Scope (Typ_2);
7563 -- If Typ_2 is a generic actual type it is declared as the subtype of
7564 -- the actual. If that actual is itself a subtype we need to use its
7565 -- own base type to check for compatibility.
7567 elsif Ekind (Base_2) = Ekind (Typ_2)
7568 and then Base_1 = Base_Type (Base_2)
7572 elsif Ekind (Base_1) = Ekind (Typ_1)
7573 and then Base_2 = Base_Type (Base_1)
7580 end Base_Types_Match;
7582 --------------------------
7583 -- Find_Designated_Type --
7584 --------------------------
7586 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7590 Desig := Directly_Designated_Type (Typ);
7592 if Ekind (Desig) = E_Incomplete_Type then
7594 -- If regular incomplete type, get full view if available
7596 if Present (Full_View (Desig)) then
7597 Desig := Full_View (Desig);
7599 -- If limited view of a type, get non-limited view if available,
7600 -- and check again for a regular incomplete type.
7602 elsif Present (Non_Limited_View (Desig)) then
7603 Desig := Get_Full_View (Non_Limited_View (Desig));
7608 end Find_Designated_Type;
7610 -------------------------------
7611 -- Matches_Limited_With_View --
7612 -------------------------------
7614 function Matches_Limited_With_View
7616 Typ_2 : Entity_Id) return Boolean
7618 function Is_Matching_Limited_View
7620 View : Entity_Id) return Boolean;
7621 -- Determine whether non-limited view View denotes type Typ in some
7622 -- conformant fashion.
7624 ------------------------------
7625 -- Is_Matching_Limited_View --
7626 ------------------------------
7628 function Is_Matching_Limited_View
7630 View : Entity_Id) return Boolean
7632 Root_Typ : Entity_Id;
7633 Root_View : Entity_Id;
7636 -- The non-limited view directly denotes the type
7641 -- The type is a subtype of the non-limited view
7643 elsif Is_Subtype_Of (Typ, View) then
7646 -- Both the non-limited view and the type denote class-wide types
7648 elsif Is_Class_Wide_Type (Typ)
7649 and then Is_Class_Wide_Type (View)
7651 Root_Typ := Root_Type (Typ);
7652 Root_View := Root_Type (View);
7654 if Root_Typ = Root_View then
7657 -- An incomplete tagged type and its full view may receive two
7658 -- distinct class-wide types when the related package has not
7659 -- been analyzed yet.
7662 -- type T is tagged; -- CW_1
7663 -- type T is tagged null record; -- CW_2
7666 -- This is because the package lacks any semantic information
7667 -- that may eventually link both views of T. As a consequence,
7668 -- a client of the limited view of Pack will see CW_2 while a
7669 -- client of the non-limited view of Pack will see CW_1.
7671 elsif Is_Incomplete_Type (Root_Typ)
7672 and then Present (Full_View (Root_Typ))
7673 and then Full_View (Root_Typ) = Root_View
7677 elsif Is_Incomplete_Type (Root_View)
7678 and then Present (Full_View (Root_View))
7679 and then Full_View (Root_View) = Root_Typ
7686 end Is_Matching_Limited_View;
7688 -- Start of processing for Matches_Limited_With_View
7691 -- In some cases a type imported through a limited_with clause, and
7692 -- its non-limited view are both visible, for example in an anonymous
7693 -- access-to-class-wide type in a formal, or when building the body
7694 -- for a subprogram renaming after the subprogram has been frozen.
7695 -- In these cases both entities designate the same type. In addition,
7696 -- if one of them is an actual in an instance, it may be a subtype of
7697 -- the non-limited view of the other.
7699 if From_Limited_With (Typ_1)
7700 and then From_Limited_With (Typ_2)
7701 and then Available_View (Typ_1) = Available_View (Typ_2)
7705 elsif From_Limited_With (Typ_1) then
7706 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7708 elsif From_Limited_With (Typ_2) then
7709 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7714 end Matches_Limited_With_View;
7718 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7720 Type_1 : Entity_Id := T1;
7721 Type_2 : Entity_Id := T2;
7723 -- Start of processing for Conforming_Types
7726 -- The context is an instance association for a formal access-to-
7727 -- subprogram type; the formal parameter types require mapping because
7728 -- they may denote other formal parameters of the generic unit.
7731 Type_1 := Get_Instance_Of (T1);
7732 Type_2 := Get_Instance_Of (T2);
7735 -- If one of the types is a view of the other introduced by a limited
7736 -- with clause, treat these as conforming for all purposes.
7738 if Matches_Limited_With_View (T1, T2) then
7741 elsif Base_Types_Match (Type_1, Type_2) then
7742 if Ctype <= Mode_Conformant then
7747 Subtypes_Statically_Match (Type_1, Type_2)
7748 and then Dimensions_Match (Type_1, Type_2);
7751 elsif Is_Incomplete_Or_Private_Type (Type_1)
7752 and then Present (Full_View (Type_1))
7753 and then Base_Types_Match (Full_View (Type_1), Type_2)
7756 Ctype <= Mode_Conformant
7757 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7759 elsif Ekind (Type_2) = E_Incomplete_Type
7760 and then Present (Full_View (Type_2))
7761 and then Base_Types_Match (Type_1, Full_View (Type_2))
7764 Ctype <= Mode_Conformant
7765 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7767 elsif Is_Private_Type (Type_2)
7768 and then In_Instance
7769 and then Present (Full_View (Type_2))
7770 and then Base_Types_Match (Type_1, Full_View (Type_2))
7773 Ctype <= Mode_Conformant
7774 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7776 -- Another confusion between views in a nested instance with an
7777 -- actual private type whose full view is not in scope.
7779 elsif Ekind (Type_2) = E_Private_Subtype
7780 and then In_Instance
7781 and then Etype (Type_2) = Type_1
7785 -- In Ada 2012, incomplete types (including limited views) can appear
7786 -- as actuals in instantiations, where they are conformant to the
7787 -- corresponding incomplete formal.
7789 elsif Is_Incomplete_Type (Type_1)
7790 and then Is_Incomplete_Type (Type_2)
7791 and then In_Instance
7792 and then (Used_As_Generic_Actual (Type_1)
7793 or else Used_As_Generic_Actual (Type_2))
7798 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7799 -- treated recursively because they carry a signature. As far as
7800 -- conformance is concerned, convention plays no role, and either
7801 -- or both could be access to protected subprograms.
7803 Are_Anonymous_Access_To_Subprogram_Types :=
7804 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7805 E_Anonymous_Access_Protected_Subprogram_Type)
7807 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7808 E_Anonymous_Access_Protected_Subprogram_Type);
7810 -- Test anonymous access type case. For this case, static subtype
7811 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7812 -- the base types because we may have built internal subtype entities
7813 -- to handle null-excluding types (see Process_Formals).
7815 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7817 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7819 -- Ada 2005 (AI-254)
7821 or else Are_Anonymous_Access_To_Subprogram_Types
7824 Desig_1 : Entity_Id;
7825 Desig_2 : Entity_Id;
7828 -- In Ada 2005, access constant indicators must match for
7829 -- subtype conformance.
7831 if Ada_Version >= Ada_2005
7832 and then Ctype >= Subtype_Conformant
7834 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7839 Desig_1 := Find_Designated_Type (Type_1);
7840 Desig_2 := Find_Designated_Type (Type_2);
7842 -- If the context is an instance association for a formal
7843 -- access-to-subprogram type; formal access parameter designated
7844 -- types require mapping because they may denote other formal
7845 -- parameters of the generic unit.
7848 Desig_1 := Get_Instance_Of (Desig_1);
7849 Desig_2 := Get_Instance_Of (Desig_2);
7852 -- It is possible for a Class_Wide_Type to be introduced for an
7853 -- incomplete type, in which case there is a separate class_ wide
7854 -- type for the full view. The types conform if their Etypes
7855 -- conform, i.e. one may be the full view of the other. This can
7856 -- only happen in the context of an access parameter, other uses
7857 -- of an incomplete Class_Wide_Type are illegal.
7859 if Is_Class_Wide_Type (Desig_1)
7861 Is_Class_Wide_Type (Desig_2)
7865 (Etype (Base_Type (Desig_1)),
7866 Etype (Base_Type (Desig_2)), Ctype);
7868 elsif Are_Anonymous_Access_To_Subprogram_Types then
7869 if Ada_Version < Ada_2005 then
7871 Ctype = Type_Conformant
7872 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7874 -- We must check the conformance of the signatures themselves
7878 Conformant : Boolean;
7881 (Desig_1, Desig_2, Ctype, False, Conformant);
7886 -- A limited view of an actual matches the corresponding
7887 -- incomplete formal.
7889 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7890 and then From_Limited_With (Desig_2)
7891 and then Used_As_Generic_Actual (Etype (Desig_2))
7896 return Base_Type (Desig_1) = Base_Type (Desig_2)
7897 and then (Ctype = Type_Conformant
7899 Subtypes_Statically_Match (Desig_1, Desig_2));
7903 -- Otherwise definitely no match
7906 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7907 and then Is_Access_Type (Type_2))
7908 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7909 and then Is_Access_Type (Type_1)))
7912 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7914 May_Hide_Profile := True;
7919 end Conforming_Types;
7921 --------------------------
7922 -- Create_Extra_Formals --
7923 --------------------------
7925 procedure Create_Extra_Formals (E : Entity_Id) is
7926 First_Extra : Entity_Id := Empty;
7928 Last_Extra : Entity_Id := Empty;
7930 function Add_Extra_Formal
7931 (Assoc_Entity : Entity_Id;
7934 Suffix : String) return Entity_Id;
7935 -- Add an extra formal to the current list of formals and extra formals.
7936 -- The extra formal is added to the end of the list of extra formals,
7937 -- and also returned as the result. These formals are always of mode IN.
7938 -- The new formal has the type Typ, is declared in Scope, and its name
7939 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7940 -- The following suffixes are currently used. They should not be changed
7941 -- without coordinating with CodePeer, which makes use of these to
7942 -- provide better messages.
7944 -- O denotes the Constrained bit.
7945 -- L denotes the accessibility level.
7946 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7947 -- the full list in exp_ch6.BIP_Formal_Kind.
7949 ----------------------
7950 -- Add_Extra_Formal --
7951 ----------------------
7953 function Add_Extra_Formal
7954 (Assoc_Entity : Entity_Id;
7957 Suffix : String) return Entity_Id
7959 EF : constant Entity_Id :=
7960 Make_Defining_Identifier (Sloc (Assoc_Entity),
7961 Chars => New_External_Name (Chars (Assoc_Entity),
7965 -- A little optimization. Never generate an extra formal for the
7966 -- _init operand of an initialization procedure, since it could
7969 if Chars (Formal) = Name_uInit then
7973 Set_Ekind (EF, E_In_Parameter);
7974 Set_Actual_Subtype (EF, Typ);
7975 Set_Etype (EF, Typ);
7976 Set_Scope (EF, Scope);
7977 Set_Mechanism (EF, Default_Mechanism);
7978 Set_Formal_Validity (EF);
7980 if No (First_Extra) then
7982 Set_Extra_Formals (Scope, EF);
7985 if Present (Last_Extra) then
7986 Set_Extra_Formal (Last_Extra, EF);
7992 end Add_Extra_Formal;
7996 Formal_Type : Entity_Id;
7997 P_Formal : Entity_Id := Empty;
7999 -- Start of processing for Create_Extra_Formals
8002 -- We never generate extra formals if expansion is not active because we
8003 -- don't need them unless we are generating code.
8005 if not Expander_Active then
8009 -- No need to generate extra formals in interface thunks whose target
8010 -- primitive has no extra formals.
8012 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
8016 -- If this is a derived subprogram then the subtypes of the parent
8017 -- subprogram's formal parameters will be used to determine the need
8018 -- for extra formals.
8020 if Is_Overloadable (E) and then Present (Alias (E)) then
8021 P_Formal := First_Formal (Alias (E));
8024 Formal := First_Formal (E);
8025 while Present (Formal) loop
8026 Last_Extra := Formal;
8027 Next_Formal (Formal);
8030 -- If Extra_Formals were already created, don't do it again. This
8031 -- situation may arise for subprogram types created as part of
8032 -- dispatching calls (see Expand_Dispatching_Call).
8034 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
8038 -- If the subprogram is a predefined dispatching subprogram then don't
8039 -- generate any extra constrained or accessibility level formals. In
8040 -- general we suppress these for internal subprograms (by not calling
8041 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
8042 -- generated stream attributes do get passed through because extra
8043 -- build-in-place formals are needed in some cases (limited 'Input).
8045 if Is_Predefined_Internal_Operation (E) then
8046 goto Test_For_Func_Result_Extras;
8049 Formal := First_Formal (E);
8050 while Present (Formal) loop
8052 -- Create extra formal for supporting the attribute 'Constrained.
8053 -- The case of a private type view without discriminants also
8054 -- requires the extra formal if the underlying type has defaulted
8057 if Ekind (Formal) /= E_In_Parameter then
8058 if Present (P_Formal) then
8059 Formal_Type := Etype (P_Formal);
8061 Formal_Type := Etype (Formal);
8064 -- Do not produce extra formals for Unchecked_Union parameters.
8065 -- Jump directly to the end of the loop.
8067 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
8068 goto Skip_Extra_Formal_Generation;
8071 if not Has_Discriminants (Formal_Type)
8072 and then Ekind (Formal_Type) in Private_Kind
8073 and then Present (Underlying_Type (Formal_Type))
8075 Formal_Type := Underlying_Type (Formal_Type);
8078 -- Suppress the extra formal if formal's subtype is constrained or
8079 -- indefinite, or we're compiling for Ada 2012 and the underlying
8080 -- type is tagged and limited. In Ada 2012, a limited tagged type
8081 -- can have defaulted discriminants, but 'Constrained is required
8082 -- to return True, so the formal is never needed (see AI05-0214).
8083 -- Note that this ensures consistency of calling sequences for
8084 -- dispatching operations when some types in a class have defaults
8085 -- on discriminants and others do not (and requiring the extra
8086 -- formal would introduce distributed overhead).
8088 -- If the type does not have a completion yet, treat as prior to
8089 -- Ada 2012 for consistency.
8091 if Has_Discriminants (Formal_Type)
8092 and then not Is_Constrained (Formal_Type)
8093 and then Is_Definite_Subtype (Formal_Type)
8094 and then (Ada_Version < Ada_2012
8095 or else No (Underlying_Type (Formal_Type))
8097 (Is_Limited_Type (Formal_Type)
8100 (Underlying_Type (Formal_Type)))))
8102 Set_Extra_Constrained
8103 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8107 -- Create extra formal for supporting accessibility checking. This
8108 -- is done for both anonymous access formals and formals of named
8109 -- access types that are marked as controlling formals. The latter
8110 -- case can occur when Expand_Dispatching_Call creates a subprogram
8111 -- type and substitutes the types of access-to-class-wide actuals
8112 -- for the anonymous access-to-specific-type of controlling formals.
8113 -- Base_Type is applied because in cases where there is a null
8114 -- exclusion the formal may have an access subtype.
8116 -- This is suppressed if we specifically suppress accessibility
8117 -- checks at the package level for either the subprogram, or the
8118 -- package in which it resides. However, we do not suppress it
8119 -- simply if the scope has accessibility checks suppressed, since
8120 -- this could cause trouble when clients are compiled with a
8121 -- different suppression setting. The explicit checks at the
8122 -- package level are safe from this point of view.
8124 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8125 or else (Is_Controlling_Formal (Formal)
8126 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8128 (Explicit_Suppress (E, Accessibility_Check)
8130 Explicit_Suppress (Scope (E), Accessibility_Check))
8133 or else Present (Extra_Accessibility (P_Formal)))
8135 Set_Extra_Accessibility
8136 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8139 -- This label is required when skipping extra formal generation for
8140 -- Unchecked_Union parameters.
8142 <<Skip_Extra_Formal_Generation>>
8144 if Present (P_Formal) then
8145 Next_Formal (P_Formal);
8148 Next_Formal (Formal);
8151 <<Test_For_Func_Result_Extras>>
8153 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8154 -- function call is ... determined by the point of call ...".
8156 if Needs_Result_Accessibility_Level (E) then
8157 Set_Extra_Accessibility_Of_Result
8158 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8161 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8162 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8164 if Is_Build_In_Place_Function (E) then
8166 Result_Subt : constant Entity_Id := Etype (E);
8167 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8168 Formal_Typ : Entity_Id;
8169 Subp_Decl : Node_Id;
8170 Discard : Entity_Id;
8173 -- In the case of functions with unconstrained result subtypes,
8174 -- add a 4-state formal indicating whether the return object is
8175 -- allocated by the caller (1), or should be allocated by the
8176 -- callee on the secondary stack (2), in the global heap (3), or
8177 -- in a user-defined storage pool (4). For the moment we just use
8178 -- Natural for the type of this formal. Note that this formal
8179 -- isn't usually needed in the case where the result subtype is
8180 -- constrained, but it is needed when the function has a tagged
8181 -- result, because generally such functions can be called in a
8182 -- dispatching context and such calls must be handled like calls
8183 -- to a class-wide function.
8185 if Needs_BIP_Alloc_Form (E) then
8188 (E, Standard_Natural,
8189 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8191 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8192 -- use a user-defined pool. This formal is not added on
8193 -- ZFP as those targets do not support pools.
8195 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8198 (E, RTE (RE_Root_Storage_Pool_Ptr),
8199 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8203 -- In the case of functions whose result type needs finalization,
8204 -- add an extra formal which represents the finalization master.
8206 if Needs_BIP_Finalization_Master (E) then
8209 (E, RTE (RE_Finalization_Master_Ptr),
8210 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8213 -- When the result type contains tasks, add two extra formals: the
8214 -- master of the tasks to be created, and the caller's activation
8217 if Has_Task (Full_Subt) then
8220 (E, RTE (RE_Master_Id),
8221 E, BIP_Formal_Suffix (BIP_Task_Master));
8224 (E, RTE (RE_Activation_Chain_Access),
8225 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8228 -- All build-in-place functions get an extra formal that will be
8229 -- passed the address of the return object within the caller.
8232 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8234 -- Incomplete_View_From_Limited_With is needed here because
8235 -- gigi gets confused if the designated type is the full view
8236 -- coming from a limited-with'ed package. In the normal case,
8237 -- (no limited with) Incomplete_View_From_Limited_With
8238 -- returns Result_Subt.
8240 Set_Directly_Designated_Type
8241 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8242 Set_Etype (Formal_Typ, Formal_Typ);
8243 Set_Depends_On_Private
8244 (Formal_Typ, Has_Private_Component (Formal_Typ));
8245 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8246 Set_Is_Access_Constant (Formal_Typ, False);
8248 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8249 -- the designated type comes from the limited view (for back-end
8252 Set_From_Limited_With
8253 (Formal_Typ, From_Limited_With (Result_Subt));
8255 Layout_Type (Formal_Typ);
8257 -- Force the definition of the Itype in case of internal function
8258 -- calls within the same or nested scope.
8260 if Is_Subprogram_Or_Generic_Subprogram (E) then
8261 Subp_Decl := Parent (E);
8263 -- The insertion point for an Itype reference should be after
8264 -- the unit declaration node of the subprogram. An exception
8265 -- to this are inherited operations from a parent type in which
8266 -- case the derived type acts as their parent.
8268 if Nkind_In (Subp_Decl, N_Function_Specification,
8269 N_Procedure_Specification)
8271 Subp_Decl := Parent (Subp_Decl);
8274 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8279 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8283 -- If this is an instance of a generic, we need to have extra formals
8286 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8287 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8289 end Create_Extra_Formals;
8291 -----------------------------
8292 -- Enter_Overloaded_Entity --
8293 -----------------------------
8295 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8296 function Matches_Predefined_Op return Boolean;
8297 -- This returns an approximation of whether S matches a predefined
8298 -- operator, based on the operator symbol, and the parameter and result
8299 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8301 ---------------------------
8302 -- Matches_Predefined_Op --
8303 ---------------------------
8305 function Matches_Predefined_Op return Boolean is
8306 Formal_1 : constant Entity_Id := First_Formal (S);
8307 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8308 Op : constant Name_Id := Chars (S);
8309 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8310 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8315 if Present (Formal_2) then
8317 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8320 -- All but "&" and "**" have same-types parameters
8329 if Type_1 /= Type_2 then
8334 -- Check parameter and result types
8342 Is_Boolean_Type (Result_Type)
8343 and then Result_Type = Type_1;
8349 Is_Integer_Type (Result_Type)
8350 and then Result_Type = Type_1;
8358 Is_Numeric_Type (Result_Type)
8359 and then Result_Type = Type_1;
8365 Is_Boolean_Type (Result_Type)
8366 and then not Is_Limited_Type (Type_1);
8374 Is_Boolean_Type (Result_Type)
8375 and then (Is_Array_Type (Type_1)
8376 or else Is_Scalar_Type (Type_1));
8378 when Name_Op_Concat =>
8379 return Is_Array_Type (Result_Type);
8381 when Name_Op_Expon =>
8383 (Is_Integer_Type (Result_Type)
8384 or else Is_Floating_Point_Type (Result_Type))
8385 and then Result_Type = Type_1
8386 and then Type_2 = Standard_Integer;
8389 raise Program_Error;
8402 Is_Numeric_Type (Result_Type)
8403 and then Result_Type = Type_1;
8407 Is_Boolean_Type (Result_Type)
8408 and then Result_Type = Type_1;
8411 raise Program_Error;
8414 end Matches_Predefined_Op;
8418 E : Entity_Id := Current_Entity_In_Scope (S);
8419 C_E : Entity_Id := Current_Entity (S);
8421 -- Start of processing for Enter_Overloaded_Entity
8425 Set_Has_Homonym (E);
8426 Set_Has_Homonym (S);
8429 Set_Is_Immediately_Visible (S);
8430 Set_Scope (S, Current_Scope);
8432 -- Chain new entity if front of homonym in current scope, so that
8433 -- homonyms are contiguous.
8435 if Present (E) and then E /= C_E then
8436 while Homonym (C_E) /= E loop
8437 C_E := Homonym (C_E);
8440 Set_Homonym (C_E, S);
8444 Set_Current_Entity (S);
8449 if Is_Inherited_Operation (S) then
8450 Append_Inherited_Subprogram (S);
8452 Append_Entity (S, Current_Scope);
8455 Set_Public_Status (S);
8457 if Debug_Flag_E then
8458 Write_Str ("New overloaded entity chain: ");
8459 Write_Name (Chars (S));
8462 while Present (E) loop
8463 Write_Str (" "); Write_Int (Int (E));
8470 -- Generate warning for hiding
8473 and then Comes_From_Source (S)
8474 and then In_Extended_Main_Source_Unit (S)
8481 -- Warn unless genuine overloading. Do not emit warning on
8482 -- hiding predefined operators in Standard (these are either an
8483 -- (artifact of our implicit declarations, or simple noise) but
8484 -- keep warning on a operator defined on a local subtype, because
8485 -- of the real danger that different operators may be applied in
8486 -- various parts of the program.
8488 -- Note that if E and S have the same scope, there is never any
8489 -- hiding. Either the two conflict, and the program is illegal,
8490 -- or S is overriding an implicit inherited subprogram.
8492 if Scope (E) /= Scope (S)
8493 and then (not Is_Overloadable (E)
8494 or else Subtype_Conformant (E, S))
8495 and then (Is_Immediately_Visible (E)
8496 or else Is_Potentially_Use_Visible (S))
8498 if Scope (E) = Standard_Standard then
8499 if Nkind (S) = N_Defining_Operator_Symbol
8500 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8502 and then Matches_Predefined_Op
8505 ("declaration of & hides predefined operator?h?", S);
8508 -- E not immediately within Standard
8511 Error_Msg_Sloc := Sloc (E);
8512 Error_Msg_N ("declaration of & hides one #?h?", S);
8517 end Enter_Overloaded_Entity;
8519 -----------------------------
8520 -- Check_Untagged_Equality --
8521 -----------------------------
8523 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8524 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8525 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8529 -- This check applies only if we have a subprogram declaration with an
8530 -- untagged record type.
8532 if Nkind (Decl) /= N_Subprogram_Declaration
8533 or else not Is_Record_Type (Typ)
8534 or else Is_Tagged_Type (Typ)
8539 -- In Ada 2012 case, we will output errors or warnings depending on
8540 -- the setting of debug flag -gnatd.E.
8542 if Ada_Version >= Ada_2012 then
8543 Error_Msg_Warn := Debug_Flag_Dot_EE;
8545 -- In earlier versions of Ada, nothing to do unless we are warning on
8546 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8549 if not Warn_On_Ada_2012_Compatibility then
8554 -- Cases where the type has already been frozen
8556 if Is_Frozen (Typ) then
8558 -- If the type is not declared in a package, or if we are in the body
8559 -- of the package or in some other scope, the new operation is not
8560 -- primitive, and therefore legal, though suspicious. Should we
8561 -- generate a warning in this case ???
8563 if Ekind (Scope (Typ)) /= E_Package
8564 or else Scope (Typ) /= Current_Scope
8568 -- If the type is a generic actual (sub)type, the operation is not
8569 -- primitive either because the base type is declared elsewhere.
8571 elsif Is_Generic_Actual_Type (Typ) then
8574 -- Here we have a definite error of declaration after freezing
8577 if Ada_Version >= Ada_2012 then
8579 ("equality operator must be declared before type & is "
8580 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8582 -- In Ada 2012 mode with error turned to warning, output one
8583 -- more warning to warn that the equality operation may not
8584 -- compose. This is the consequence of ignoring the error.
8586 if Error_Msg_Warn then
8587 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8592 ("equality operator must be declared before type& is "
8593 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8596 -- If we are in the package body, we could just move the
8597 -- declaration to the package spec, so add a message saying that.
8599 if In_Package_Body (Scope (Typ)) then
8600 if Ada_Version >= Ada_2012 then
8602 ("\move declaration to package spec<<", Eq_Op);
8605 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8608 -- Otherwise try to find the freezing point
8611 Obj_Decl := Next (Parent (Typ));
8612 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8613 if Nkind (Obj_Decl) = N_Object_Declaration
8614 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8616 -- Freezing point, output warnings
8618 if Ada_Version >= Ada_2012 then
8620 ("type& is frozen by declaration??", Obj_Decl, Typ);
8622 ("\an equality operator cannot be declared after "
8627 ("type& is frozen by declaration (Ada 2012)?y?",
8630 ("\an equality operator cannot be declared after "
8631 & "this point (Ada 2012)?y?",
8643 -- Here if type is not frozen yet. It is illegal to have a primitive
8644 -- equality declared in the private part if the type is visible.
8646 elsif not In_Same_List (Parent (Typ), Decl)
8647 and then not Is_Limited_Type (Typ)
8649 -- Shouldn't we give an RM reference here???
8651 if Ada_Version >= Ada_2012 then
8653 ("equality operator appears too late<<", Eq_Op);
8656 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8659 -- No error detected
8664 end Check_Untagged_Equality;
8666 -----------------------------
8667 -- Find_Corresponding_Spec --
8668 -----------------------------
8670 function Find_Corresponding_Spec
8672 Post_Error : Boolean := True) return Entity_Id
8674 Spec : constant Node_Id := Specification (N);
8675 Designator : constant Entity_Id := Defining_Entity (Spec);
8679 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8680 -- Even if fully conformant, a body may depend on a generic actual when
8681 -- the spec does not, or vice versa, in which case they were distinct
8682 -- entities in the generic.
8684 -------------------------------
8685 -- Different_Generic_Profile --
8686 -------------------------------
8688 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8691 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8692 -- Check that the types of corresponding formals have the same
8693 -- generic actual if any. We have to account for subtypes of a
8694 -- generic formal, declared between a spec and a body, which may
8695 -- appear distinct in an instance but matched in the generic, and
8696 -- the subtype may be used either in the spec or the body of the
8697 -- subprogram being checked.
8699 -------------------------
8700 -- Same_Generic_Actual --
8701 -------------------------
8703 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8705 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8706 -- Predicate to check whether S1 is a subtype of S2 in the source
8709 -------------------------
8710 -- Is_Declared_Subtype --
8711 -------------------------
8713 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8715 return Comes_From_Source (Parent (S1))
8716 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8717 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8718 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8719 end Is_Declared_Subtype;
8721 -- Start of processing for Same_Generic_Actual
8724 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8725 or else Is_Declared_Subtype (T1, T2)
8726 or else Is_Declared_Subtype (T2, T1);
8727 end Same_Generic_Actual;
8729 -- Start of processing for Different_Generic_Profile
8732 if not In_Instance then
8735 elsif Ekind (E) = E_Function
8736 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8741 F1 := First_Formal (Designator);
8742 F2 := First_Formal (E);
8743 while Present (F1) loop
8744 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8753 end Different_Generic_Profile;
8755 -- Start of processing for Find_Corresponding_Spec
8758 E := Current_Entity (Designator);
8759 while Present (E) loop
8761 -- We are looking for a matching spec. It must have the same scope,
8762 -- and the same name, and either be type conformant, or be the case
8763 -- of a library procedure spec and its body (which belong to one
8764 -- another regardless of whether they are type conformant or not).
8766 if Scope (E) = Current_Scope then
8767 if Current_Scope = Standard_Standard
8768 or else (Ekind (E) = Ekind (Designator)
8769 and then Type_Conformant (E, Designator))
8771 -- Within an instantiation, we know that spec and body are
8772 -- subtype conformant, because they were subtype conformant in
8773 -- the generic. We choose the subtype-conformant entity here as
8774 -- well, to resolve spurious ambiguities in the instance that
8775 -- were not present in the generic (i.e. when two different
8776 -- types are given the same actual). If we are looking for a
8777 -- spec to match a body, full conformance is expected.
8781 -- Inherit the convention and "ghostness" of the matching
8782 -- spec to ensure proper full and subtype conformance.
8784 Set_Convention (Designator, Convention (E));
8786 -- Skip past subprogram bodies and subprogram renamings that
8787 -- may appear to have a matching spec, but that aren't fully
8788 -- conformant with it. That can occur in cases where an
8789 -- actual type causes unrelated homographs in the instance.
8791 if Nkind_In (N, N_Subprogram_Body,
8792 N_Subprogram_Renaming_Declaration)
8793 and then Present (Homonym (E))
8794 and then not Fully_Conformant (Designator, E)
8798 elsif not Subtype_Conformant (Designator, E) then
8801 elsif Different_Generic_Profile (E) then
8806 -- Ada 2012 (AI05-0165): For internally generated bodies of
8807 -- null procedures locate the internally generated spec. We
8808 -- enforce mode conformance since a tagged type may inherit
8809 -- from interfaces several null primitives which differ only
8810 -- in the mode of the formals.
8812 if not (Comes_From_Source (E))
8813 and then Is_Null_Procedure (E)
8814 and then not Mode_Conformant (Designator, E)
8818 -- For null procedures coming from source that are completions,
8819 -- analysis of the generated body will establish the link.
8821 elsif Comes_From_Source (E)
8822 and then Nkind (Spec) = N_Procedure_Specification
8823 and then Null_Present (Spec)
8827 -- Expression functions can be completions, but cannot be
8828 -- completed by an explicit body.
8830 elsif Comes_From_Source (E)
8831 and then Comes_From_Source (N)
8832 and then Nkind (N) = N_Subprogram_Body
8833 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8834 N_Expression_Function
8836 Error_Msg_Sloc := Sloc (E);
8837 Error_Msg_N ("body conflicts with expression function#", N);
8840 elsif not Has_Completion (E) then
8841 if Nkind (N) /= N_Subprogram_Body_Stub then
8842 Set_Corresponding_Spec (N, E);
8845 Set_Has_Completion (E);
8848 elsif Nkind (Parent (N)) = N_Subunit then
8850 -- If this is the proper body of a subunit, the completion
8851 -- flag is set when analyzing the stub.
8855 -- If E is an internal function with a controlling result that
8856 -- was created for an operation inherited by a null extension,
8857 -- it may be overridden by a body without a previous spec (one
8858 -- more reason why these should be shunned). In that case we
8859 -- remove the generated body if present, because the current
8860 -- one is the explicit overriding.
8862 elsif Ekind (E) = E_Function
8863 and then Ada_Version >= Ada_2005
8864 and then not Comes_From_Source (E)
8865 and then Has_Controlling_Result (E)
8866 and then Is_Null_Extension (Etype (E))
8867 and then Comes_From_Source (Spec)
8869 Set_Has_Completion (E, False);
8872 and then Nkind (Parent (E)) = N_Function_Specification
8875 (Unit_Declaration_Node
8876 (Corresponding_Body (Unit_Declaration_Node (E))));
8880 -- If expansion is disabled, or if the wrapper function has
8881 -- not been generated yet, this a late body overriding an
8882 -- inherited operation, or it is an overriding by some other
8883 -- declaration before the controlling result is frozen. In
8884 -- either case this is a declaration of a new entity.
8890 -- If the body already exists, then this is an error unless
8891 -- the previous declaration is the implicit declaration of a
8892 -- derived subprogram. It is also legal for an instance to
8893 -- contain type conformant overloadable declarations (but the
8894 -- generic declaration may not), per 8.3(26/2).
8896 elsif No (Alias (E))
8897 and then not Is_Intrinsic_Subprogram (E)
8898 and then not In_Instance
8901 Error_Msg_Sloc := Sloc (E);
8903 if Is_Imported (E) then
8905 ("body not allowed for imported subprogram & declared#",
8908 Error_Msg_NE ("duplicate body for & declared#", N, E);
8912 -- Child units cannot be overloaded, so a conformance mismatch
8913 -- between body and a previous spec is an error.
8915 elsif Is_Child_Unit (E)
8917 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8919 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8924 ("body of child unit does not match previous declaration", N);
8932 -- On exit, we know that no previous declaration of subprogram exists
8935 end Find_Corresponding_Spec;
8937 ----------------------
8938 -- Fully_Conformant --
8939 ----------------------
8941 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8944 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8946 end Fully_Conformant;
8948 ----------------------------------
8949 -- Fully_Conformant_Expressions --
8950 ----------------------------------
8952 function Fully_Conformant_Expressions
8953 (Given_E1 : Node_Id;
8954 Given_E2 : Node_Id) return Boolean
8956 E1 : constant Node_Id := Original_Node (Given_E1);
8957 E2 : constant Node_Id := Original_Node (Given_E2);
8958 -- We always test conformance on original nodes, since it is possible
8959 -- for analysis and/or expansion to make things look as though they
8960 -- conform when they do not, e.g. by converting 1+2 into 3.
8962 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8963 renames Fully_Conformant_Expressions;
8965 function FCL (L1, L2 : List_Id) return Boolean;
8966 -- Compare elements of two lists for conformance. Elements have to be
8967 -- conformant, and actuals inserted as default parameters do not match
8968 -- explicit actuals with the same value.
8970 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8971 -- Compare an operator node with a function call
8977 function FCL (L1, L2 : List_Id) return Boolean is
8981 if L1 = No_List then
8987 if L2 = No_List then
8993 -- Compare two lists, skipping rewrite insertions (we want to compare
8994 -- the original trees, not the expanded versions).
8997 if Is_Rewrite_Insertion (N1) then
8999 elsif Is_Rewrite_Insertion (N2) then
9005 elsif not FCE (N1, N2) then
9018 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
9019 Actuals : constant List_Id := Parameter_Associations (Call_Node);
9024 or else Entity (Op_Node) /= Entity (Name (Call_Node))
9029 Act := First (Actuals);
9031 if Nkind (Op_Node) in N_Binary_Op then
9032 if not FCE (Left_Opnd (Op_Node), Act) then
9039 return Present (Act)
9040 and then FCE (Right_Opnd (Op_Node), Act)
9041 and then No (Next (Act));
9045 -- Start of processing for Fully_Conformant_Expressions
9048 -- Nonconformant if paren count does not match. Note: if some idiot
9049 -- complains that we don't do this right for more than 3 levels of
9050 -- parentheses, they will be treated with the respect they deserve.
9052 if Paren_Count (E1) /= Paren_Count (E2) then
9055 -- If same entities are referenced, then they are conformant even if
9056 -- they have different forms (RM 8.3.1(19-20)).
9058 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
9059 if Present (Entity (E1)) then
9060 return Entity (E1) = Entity (E2)
9062 -- One may be a discriminant that has been replaced by the
9063 -- corresponding discriminal.
9066 (Chars (Entity (E1)) = Chars (Entity (E2))
9067 and then Ekind (Entity (E1)) = E_Discriminant
9068 and then Ekind (Entity (E2)) = E_In_Parameter)
9070 -- The discriminant of a protected type is transformed into
9071 -- a local constant and then into a parameter of a protected
9075 (Ekind (Entity (E1)) = E_Constant
9076 and then Ekind (Entity (E2)) = E_In_Parameter
9077 and then Present (Discriminal_Link (Entity (E1)))
9078 and then Discriminal_Link (Entity (E1)) =
9079 Discriminal_Link (Entity (E2)))
9081 -- AI12-050: The loop variables of quantified expressions
9082 -- match if they have the same identifier, even though they
9083 -- are different entities.
9086 (Chars (Entity (E1)) = Chars (Entity (E2))
9087 and then Ekind (Entity (E1)) = E_Loop_Parameter
9088 and then Ekind (Entity (E2)) = E_Loop_Parameter);
9090 elsif Nkind (E1) = N_Expanded_Name
9091 and then Nkind (E2) = N_Expanded_Name
9092 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9093 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9095 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9098 -- Identifiers in component associations don't always have
9099 -- entities, but their names must conform.
9101 return Nkind (E1) = N_Identifier
9102 and then Nkind (E2) = N_Identifier
9103 and then Chars (E1) = Chars (E2);
9106 elsif Nkind (E1) = N_Character_Literal
9107 and then Nkind (E2) = N_Expanded_Name
9109 return Nkind (Selector_Name (E2)) = N_Character_Literal
9110 and then Chars (E1) = Chars (Selector_Name (E2));
9112 elsif Nkind (E2) = N_Character_Literal
9113 and then Nkind (E1) = N_Expanded_Name
9115 return Nkind (Selector_Name (E1)) = N_Character_Literal
9116 and then Chars (E2) = Chars (Selector_Name (E1));
9118 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9119 return FCO (E1, E2);
9121 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9122 return FCO (E2, E1);
9124 -- Otherwise we must have the same syntactic entity
9126 elsif Nkind (E1) /= Nkind (E2) then
9129 -- At this point, we specialize by node type
9135 FCL (Expressions (E1), Expressions (E2))
9137 FCL (Component_Associations (E1),
9138 Component_Associations (E2));
9141 if Nkind (Expression (E1)) = N_Qualified_Expression
9143 Nkind (Expression (E2)) = N_Qualified_Expression
9145 return FCE (Expression (E1), Expression (E2));
9147 -- Check that the subtype marks and any constraints
9152 Indic1 : constant Node_Id := Expression (E1);
9153 Indic2 : constant Node_Id := Expression (E2);
9158 if Nkind (Indic1) /= N_Subtype_Indication then
9160 Nkind (Indic2) /= N_Subtype_Indication
9161 and then Entity (Indic1) = Entity (Indic2);
9163 elsif Nkind (Indic2) /= N_Subtype_Indication then
9165 Nkind (Indic1) /= N_Subtype_Indication
9166 and then Entity (Indic1) = Entity (Indic2);
9169 if Entity (Subtype_Mark (Indic1)) /=
9170 Entity (Subtype_Mark (Indic2))
9175 Elt1 := First (Constraints (Constraint (Indic1)));
9176 Elt2 := First (Constraints (Constraint (Indic2)));
9177 while Present (Elt1) and then Present (Elt2) loop
9178 if not FCE (Elt1, Elt2) then
9191 when N_Attribute_Reference =>
9193 Attribute_Name (E1) = Attribute_Name (E2)
9194 and then FCL (Expressions (E1), Expressions (E2));
9198 Entity (E1) = Entity (E2)
9199 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9200 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9202 when N_Membership_Test
9206 FCE (Left_Opnd (E1), Left_Opnd (E2))
9208 FCE (Right_Opnd (E1), Right_Opnd (E2));
9210 when N_Case_Expression =>
9216 if not FCE (Expression (E1), Expression (E2)) then
9220 Alt1 := First (Alternatives (E1));
9221 Alt2 := First (Alternatives (E2));
9223 if Present (Alt1) /= Present (Alt2) then
9225 elsif No (Alt1) then
9229 if not FCE (Expression (Alt1), Expression (Alt2))
9230 or else not FCL (Discrete_Choices (Alt1),
9231 Discrete_Choices (Alt2))
9242 when N_Character_Literal =>
9244 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9246 when N_Component_Association =>
9248 FCL (Choices (E1), Choices (E2))
9250 FCE (Expression (E1), Expression (E2));
9252 when N_Explicit_Dereference =>
9254 FCE (Prefix (E1), Prefix (E2));
9256 when N_Extension_Aggregate =>
9258 FCL (Expressions (E1), Expressions (E2))
9259 and then Null_Record_Present (E1) =
9260 Null_Record_Present (E2)
9261 and then FCL (Component_Associations (E1),
9262 Component_Associations (E2));
9264 when N_Function_Call =>
9266 FCE (Name (E1), Name (E2))
9268 FCL (Parameter_Associations (E1),
9269 Parameter_Associations (E2));
9271 when N_If_Expression =>
9273 FCL (Expressions (E1), Expressions (E2));
9275 when N_Indexed_Component =>
9277 FCE (Prefix (E1), Prefix (E2))
9279 FCL (Expressions (E1), Expressions (E2));
9281 when N_Integer_Literal =>
9282 return (Intval (E1) = Intval (E2));
9287 when N_Operator_Symbol =>
9289 Chars (E1) = Chars (E2);
9291 when N_Others_Choice =>
9294 when N_Parameter_Association =>
9296 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9297 and then FCE (Explicit_Actual_Parameter (E1),
9298 Explicit_Actual_Parameter (E2));
9300 when N_Qualified_Expression
9302 | N_Unchecked_Type_Conversion
9305 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9307 FCE (Expression (E1), Expression (E2));
9309 when N_Quantified_Expression =>
9310 if not FCE (Condition (E1), Condition (E2)) then
9314 if Present (Loop_Parameter_Specification (E1))
9315 and then Present (Loop_Parameter_Specification (E2))
9318 L1 : constant Node_Id :=
9319 Loop_Parameter_Specification (E1);
9320 L2 : constant Node_Id :=
9321 Loop_Parameter_Specification (E2);
9325 Reverse_Present (L1) = Reverse_Present (L2)
9327 FCE (Defining_Identifier (L1),
9328 Defining_Identifier (L2))
9330 FCE (Discrete_Subtype_Definition (L1),
9331 Discrete_Subtype_Definition (L2));
9334 elsif Present (Iterator_Specification (E1))
9335 and then Present (Iterator_Specification (E2))
9338 I1 : constant Node_Id := Iterator_Specification (E1);
9339 I2 : constant Node_Id := Iterator_Specification (E2);
9343 FCE (Defining_Identifier (I1),
9344 Defining_Identifier (I2))
9346 Of_Present (I1) = Of_Present (I2)
9348 Reverse_Present (I1) = Reverse_Present (I2)
9349 and then FCE (Name (I1), Name (I2))
9350 and then FCE (Subtype_Indication (I1),
9351 Subtype_Indication (I2));
9354 -- The quantified expressions used different specifications to
9355 -- walk their respective ranges.
9363 FCE (Low_Bound (E1), Low_Bound (E2))
9365 FCE (High_Bound (E1), High_Bound (E2));
9367 when N_Real_Literal =>
9368 return (Realval (E1) = Realval (E2));
9370 when N_Selected_Component =>
9372 FCE (Prefix (E1), Prefix (E2))
9374 FCE (Selector_Name (E1), Selector_Name (E2));
9378 FCE (Prefix (E1), Prefix (E2))
9380 FCE (Discrete_Range (E1), Discrete_Range (E2));
9382 when N_String_Literal =>
9384 S1 : constant String_Id := Strval (E1);
9385 S2 : constant String_Id := Strval (E2);
9386 L1 : constant Nat := String_Length (S1);
9387 L2 : constant Nat := String_Length (S2);
9394 for J in 1 .. L1 loop
9395 if Get_String_Char (S1, J) /=
9396 Get_String_Char (S2, J)
9408 Entity (E1) = Entity (E2)
9410 FCE (Right_Opnd (E1), Right_Opnd (E2));
9412 -- All other node types cannot appear in this context. Strictly
9413 -- we should raise a fatal internal error. Instead we just ignore
9414 -- the nodes. This means that if anyone makes a mistake in the
9415 -- expander and mucks an expression tree irretrievably, the result
9416 -- will be a failure to detect a (probably very obscure) case
9417 -- of non-conformance, which is better than bombing on some
9418 -- case where two expressions do in fact conform.
9424 end Fully_Conformant_Expressions;
9426 ----------------------------------------
9427 -- Fully_Conformant_Discrete_Subtypes --
9428 ----------------------------------------
9430 function Fully_Conformant_Discrete_Subtypes
9431 (Given_S1 : Node_Id;
9432 Given_S2 : Node_Id) return Boolean
9434 S1 : constant Node_Id := Original_Node (Given_S1);
9435 S2 : constant Node_Id := Original_Node (Given_S2);
9437 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9438 -- Special-case for a bound given by a discriminant, which in the body
9439 -- is replaced with the discriminal of the enclosing type.
9441 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9442 -- Check both bounds
9444 -----------------------
9445 -- Conforming_Bounds --
9446 -----------------------
9448 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9450 if Is_Entity_Name (B1)
9451 and then Is_Entity_Name (B2)
9452 and then Ekind (Entity (B1)) = E_Discriminant
9454 return Chars (B1) = Chars (B2);
9457 return Fully_Conformant_Expressions (B1, B2);
9459 end Conforming_Bounds;
9461 -----------------------
9462 -- Conforming_Ranges --
9463 -----------------------
9465 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9468 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9470 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9471 end Conforming_Ranges;
9473 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9476 if Nkind (S1) /= Nkind (S2) then
9479 elsif Is_Entity_Name (S1) then
9480 return Entity (S1) = Entity (S2);
9482 elsif Nkind (S1) = N_Range then
9483 return Conforming_Ranges (S1, S2);
9485 elsif Nkind (S1) = N_Subtype_Indication then
9487 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9490 (Range_Expression (Constraint (S1)),
9491 Range_Expression (Constraint (S2)));
9495 end Fully_Conformant_Discrete_Subtypes;
9497 --------------------
9498 -- Install_Entity --
9499 --------------------
9501 procedure Install_Entity (E : Entity_Id) is
9502 Prev : constant Entity_Id := Current_Entity (E);
9504 Set_Is_Immediately_Visible (E);
9505 Set_Current_Entity (E);
9506 Set_Homonym (E, Prev);
9509 ---------------------
9510 -- Install_Formals --
9511 ---------------------
9513 procedure Install_Formals (Id : Entity_Id) is
9516 F := First_Formal (Id);
9517 while Present (F) loop
9521 end Install_Formals;
9523 -----------------------------
9524 -- Is_Interface_Conformant --
9525 -----------------------------
9527 function Is_Interface_Conformant
9528 (Tagged_Type : Entity_Id;
9529 Iface_Prim : Entity_Id;
9530 Prim : Entity_Id) return Boolean
9532 -- The operation may in fact be an inherited (implicit) operation
9533 -- rather than the original interface primitive, so retrieve the
9534 -- ultimate ancestor.
9536 Iface : constant Entity_Id :=
9537 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9538 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9540 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9541 -- Return the controlling formal of Prim
9543 ------------------------
9544 -- Controlling_Formal --
9545 ------------------------
9547 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9551 E := First_Entity (Prim);
9552 while Present (E) loop
9553 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9561 end Controlling_Formal;
9565 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9566 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9568 -- Start of processing for Is_Interface_Conformant
9571 pragma Assert (Is_Subprogram (Iface_Prim)
9572 and then Is_Subprogram (Prim)
9573 and then Is_Dispatching_Operation (Iface_Prim)
9574 and then Is_Dispatching_Operation (Prim));
9576 pragma Assert (Is_Interface (Iface)
9577 or else (Present (Alias (Iface_Prim))
9580 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9582 if Prim = Iface_Prim
9583 or else not Is_Subprogram (Prim)
9584 or else Ekind (Prim) /= Ekind (Iface_Prim)
9585 or else not Is_Dispatching_Operation (Prim)
9586 or else Scope (Prim) /= Scope (Tagged_Type)
9588 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9589 or else not Primitive_Names_Match (Iface_Prim, Prim)
9593 -- The mode of the controlling formals must match
9595 elsif Present (Iface_Ctrl_F)
9596 and then Present (Prim_Ctrl_F)
9597 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9601 -- Case of a procedure, or a function whose result type matches the
9602 -- result type of the interface primitive, or a function that has no
9603 -- controlling result (I or access I).
9605 elsif Ekind (Iface_Prim) = E_Procedure
9606 or else Etype (Prim) = Etype (Iface_Prim)
9607 or else not Has_Controlling_Result (Prim)
9609 return Type_Conformant
9610 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9612 -- Case of a function returning an interface, or an access to one. Check
9613 -- that the return types correspond.
9615 elsif Implements_Interface (Typ, Iface) then
9616 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9618 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9623 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9624 Skip_Controlling_Formals => True);
9630 end Is_Interface_Conformant;
9632 ---------------------------------
9633 -- Is_Non_Overriding_Operation --
9634 ---------------------------------
9636 function Is_Non_Overriding_Operation
9637 (Prev_E : Entity_Id;
9638 New_E : Entity_Id) return Boolean
9642 G_Typ : Entity_Id := Empty;
9644 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9645 -- If F_Type is a derived type associated with a generic actual subtype,
9646 -- then return its Generic_Parent_Type attribute, else return Empty.
9648 function Types_Correspond
9649 (P_Type : Entity_Id;
9650 N_Type : Entity_Id) return Boolean;
9651 -- Returns true if and only if the types (or designated types in the
9652 -- case of anonymous access types) are the same or N_Type is derived
9653 -- directly or indirectly from P_Type.
9655 -----------------------------
9656 -- Get_Generic_Parent_Type --
9657 -----------------------------
9659 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9665 if Is_Derived_Type (F_Typ)
9666 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9668 -- The tree must be traversed to determine the parent subtype in
9669 -- the generic unit, which unfortunately isn't always available
9670 -- via semantic attributes. ??? (Note: The use of Original_Node
9671 -- is needed for cases where a full derived type has been
9674 -- If the parent type is a scalar type, the derivation creates
9675 -- an anonymous base type for it, and the source type is its
9678 if Is_Scalar_Type (F_Typ)
9679 and then not Comes_From_Source (F_Typ)
9683 (Original_Node (Parent (First_Subtype (F_Typ))));
9685 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9687 if Nkind (Defn) = N_Derived_Type_Definition then
9688 Indic := Subtype_Indication (Defn);
9690 if Nkind (Indic) = N_Subtype_Indication then
9691 G_Typ := Entity (Subtype_Mark (Indic));
9693 G_Typ := Entity (Indic);
9696 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9697 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9699 return Generic_Parent_Type (Parent (G_Typ));
9705 end Get_Generic_Parent_Type;
9707 ----------------------
9708 -- Types_Correspond --
9709 ----------------------
9711 function Types_Correspond
9712 (P_Type : Entity_Id;
9713 N_Type : Entity_Id) return Boolean
9715 Prev_Type : Entity_Id := Base_Type (P_Type);
9716 New_Type : Entity_Id := Base_Type (N_Type);
9719 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9720 Prev_Type := Designated_Type (Prev_Type);
9723 if Ekind (New_Type) = E_Anonymous_Access_Type then
9724 New_Type := Designated_Type (New_Type);
9727 if Prev_Type = New_Type then
9730 elsif not Is_Class_Wide_Type (New_Type) then
9731 while Etype (New_Type) /= New_Type loop
9732 New_Type := Etype (New_Type);
9734 if New_Type = Prev_Type then
9740 end Types_Correspond;
9742 -- Start of processing for Is_Non_Overriding_Operation
9745 -- In the case where both operations are implicit derived subprograms
9746 -- then neither overrides the other. This can only occur in certain
9747 -- obscure cases (e.g., derivation from homographs created in a generic
9750 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9753 elsif Ekind (Current_Scope) = E_Package
9754 and then Is_Generic_Instance (Current_Scope)
9755 and then In_Private_Part (Current_Scope)
9756 and then Comes_From_Source (New_E)
9758 -- We examine the formals and result type of the inherited operation,
9759 -- to determine whether their type is derived from (the instance of)
9760 -- a generic type. The first such formal or result type is the one
9763 Formal := First_Formal (Prev_E);
9765 while Present (Formal) loop
9766 F_Typ := Base_Type (Etype (Formal));
9768 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9769 F_Typ := Designated_Type (F_Typ);
9772 G_Typ := Get_Generic_Parent_Type (F_Typ);
9773 exit when Present (G_Typ);
9775 Next_Formal (Formal);
9778 -- If the function dispatches on result check the result type
9780 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9781 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9788 -- If the generic type is a private type, then the original operation
9789 -- was not overriding in the generic, because there was no primitive
9790 -- operation to override.
9792 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9793 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9794 N_Formal_Private_Type_Definition
9798 -- The generic parent type is the ancestor of a formal derived
9799 -- type declaration. We need to check whether it has a primitive
9800 -- operation that should be overridden by New_E in the generic.
9804 P_Formal : Entity_Id;
9805 N_Formal : Entity_Id;
9809 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9812 while Present (Prim_Elt) loop
9813 P_Prim := Node (Prim_Elt);
9815 if Chars (P_Prim) = Chars (New_E)
9816 and then Ekind (P_Prim) = Ekind (New_E)
9818 P_Formal := First_Formal (P_Prim);
9819 N_Formal := First_Formal (New_E);
9820 while Present (P_Formal) and then Present (N_Formal) loop
9821 P_Typ := Etype (P_Formal);
9822 N_Typ := Etype (N_Formal);
9824 if not Types_Correspond (P_Typ, N_Typ) then
9828 Next_Entity (P_Formal);
9829 Next_Entity (N_Formal);
9832 -- Found a matching primitive operation belonging to the
9833 -- formal ancestor type, so the new subprogram is
9837 and then No (N_Formal)
9838 and then (Ekind (New_E) /= E_Function
9841 (Etype (P_Prim), Etype (New_E)))
9847 Next_Elmt (Prim_Elt);
9850 -- If no match found, then the new subprogram does not override
9851 -- in the generic (nor in the instance).
9853 -- If the type in question is not abstract, and the subprogram
9854 -- is, this will be an error if the new operation is in the
9855 -- private part of the instance. Emit a warning now, which will
9856 -- make the subsequent error message easier to understand.
9858 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9859 and then Is_Abstract_Subprogram (Prev_E)
9860 and then In_Private_Part (Current_Scope)
9862 Error_Msg_Node_2 := F_Typ;
9864 ("private operation& in generic unit does not override "
9865 & "any primitive operation of& (RM 12.3 (18))??",
9875 end Is_Non_Overriding_Operation;
9877 -------------------------------------
9878 -- List_Inherited_Pre_Post_Aspects --
9879 -------------------------------------
9881 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9883 if Opt.List_Inherited_Aspects
9884 and then Is_Subprogram_Or_Generic_Subprogram (E)
9887 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9892 for Index in Subps'Range loop
9893 Items := Contract (Subps (Index));
9895 if Present (Items) then
9896 Prag := Pre_Post_Conditions (Items);
9897 while Present (Prag) loop
9898 Error_Msg_Sloc := Sloc (Prag);
9900 if Class_Present (Prag)
9901 and then not Split_PPC (Prag)
9903 if Pragma_Name (Prag) = Name_Precondition then
9905 ("info: & inherits `Pre''Class` aspect from "
9909 ("info: & inherits `Post''Class` aspect from "
9914 Prag := Next_Pragma (Prag);
9920 end List_Inherited_Pre_Post_Aspects;
9922 ------------------------------
9923 -- Make_Inequality_Operator --
9924 ------------------------------
9926 -- S is the defining identifier of an equality operator. We build a
9927 -- subprogram declaration with the right signature. This operation is
9928 -- intrinsic, because it is always expanded as the negation of the
9929 -- call to the equality function.
9931 procedure Make_Inequality_Operator (S : Entity_Id) is
9932 Loc : constant Source_Ptr := Sloc (S);
9935 Op_Name : Entity_Id;
9937 FF : constant Entity_Id := First_Formal (S);
9938 NF : constant Entity_Id := Next_Formal (FF);
9941 -- Check that equality was properly defined, ignore call if not
9948 A : constant Entity_Id :=
9949 Make_Defining_Identifier (Sloc (FF),
9950 Chars => Chars (FF));
9952 B : constant Entity_Id :=
9953 Make_Defining_Identifier (Sloc (NF),
9954 Chars => Chars (NF));
9957 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9959 Formals := New_List (
9960 Make_Parameter_Specification (Loc,
9961 Defining_Identifier => A,
9963 New_Occurrence_Of (Etype (First_Formal (S)),
9964 Sloc (Etype (First_Formal (S))))),
9966 Make_Parameter_Specification (Loc,
9967 Defining_Identifier => B,
9969 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9970 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9973 Make_Subprogram_Declaration (Loc,
9975 Make_Function_Specification (Loc,
9976 Defining_Unit_Name => Op_Name,
9977 Parameter_Specifications => Formals,
9978 Result_Definition =>
9979 New_Occurrence_Of (Standard_Boolean, Loc)));
9981 -- Insert inequality right after equality if it is explicit or after
9982 -- the derived type when implicit. These entities are created only
9983 -- for visibility purposes, and eventually replaced in the course
9984 -- of expansion, so they do not need to be attached to the tree and
9985 -- seen by the back-end. Keeping them internal also avoids spurious
9986 -- freezing problems. The declaration is inserted in the tree for
9987 -- analysis, and removed afterwards. If the equality operator comes
9988 -- from an explicit declaration, attach the inequality immediately
9989 -- after. Else the equality is inherited from a derived type
9990 -- declaration, so insert inequality after that declaration.
9992 if No (Alias (S)) then
9993 Insert_After (Unit_Declaration_Node (S), Decl);
9994 elsif Is_List_Member (Parent (S)) then
9995 Insert_After (Parent (S), Decl);
9997 Insert_After (Parent (Etype (First_Formal (S))), Decl);
10000 Mark_Rewrite_Insertion (Decl);
10001 Set_Is_Intrinsic_Subprogram (Op_Name);
10004 Set_Has_Completion (Op_Name);
10005 Set_Corresponding_Equality (Op_Name, S);
10006 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
10008 end Make_Inequality_Operator;
10010 ----------------------
10011 -- May_Need_Actuals --
10012 ----------------------
10014 procedure May_Need_Actuals (Fun : Entity_Id) is
10019 F := First_Formal (Fun);
10021 while Present (F) loop
10022 if No (Default_Value (F)) then
10030 Set_Needs_No_Actuals (Fun, B);
10031 end May_Need_Actuals;
10033 ---------------------
10034 -- Mode_Conformant --
10035 ---------------------
10037 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
10040 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
10042 end Mode_Conformant;
10044 ---------------------------
10045 -- New_Overloaded_Entity --
10046 ---------------------------
10048 procedure New_Overloaded_Entity
10050 Derived_Type : Entity_Id := Empty)
10052 Overridden_Subp : Entity_Id := Empty;
10053 -- Set if the current scope has an operation that is type-conformant
10054 -- with S, and becomes hidden by S.
10056 Is_Primitive_Subp : Boolean;
10057 -- Set to True if the new subprogram is primitive
10060 -- Entity that S overrides
10062 Prev_Vis : Entity_Id := Empty;
10063 -- Predecessor of E in Homonym chain
10065 procedure Check_For_Primitive_Subprogram
10066 (Is_Primitive : out Boolean;
10067 Is_Overriding : Boolean := False);
10068 -- If the subprogram being analyzed is a primitive operation of the type
10069 -- of a formal or result, set the Has_Primitive_Operations flag on the
10070 -- type, and set Is_Primitive to True (otherwise set to False). Set the
10071 -- corresponding flag on the entity itself for later use.
10073 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10074 -- True if a) E is a subprogram whose first formal is a concurrent type
10075 -- defined in the scope of E that has some entry or subprogram whose
10076 -- profile matches E, or b) E is an internally built dispatching
10077 -- subprogram of a protected type and there is a matching subprogram
10078 -- defined in the enclosing scope of the protected type, or c) E is
10079 -- an entry of a synchronized type and a matching procedure has been
10080 -- previously defined in the enclosing scope of the synchronized type.
10082 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10083 -- Check that E is declared in the private part of the current package,
10084 -- or in the package body, where it may hide a previous declaration.
10085 -- We can't use In_Private_Part by itself because this flag is also
10086 -- set when freezing entities, so we must examine the place of the
10087 -- declaration in the tree, and recognize wrapper packages as well.
10089 function Is_Overriding_Alias
10090 (Old_E : Entity_Id;
10091 New_E : Entity_Id) return Boolean;
10092 -- Check whether new subprogram and old subprogram are both inherited
10093 -- from subprograms that have distinct dispatch table entries. This can
10094 -- occur with derivations from instances with accidental homonyms. The
10095 -- function is conservative given that the converse is only true within
10096 -- instances that contain accidental overloadings.
10098 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10099 -- Report conflict between entities S and E
10101 ------------------------------------
10102 -- Check_For_Primitive_Subprogram --
10103 ------------------------------------
10105 procedure Check_For_Primitive_Subprogram
10106 (Is_Primitive : out Boolean;
10107 Is_Overriding : Boolean := False)
10109 Formal : Entity_Id;
10113 function Visible_Part_Type (T : Entity_Id) return Boolean;
10114 -- Returns true if T is declared in the visible part of the current
10115 -- package scope; otherwise returns false. Assumes that T is declared
10118 procedure Check_Private_Overriding (T : Entity_Id);
10119 -- Checks that if a primitive abstract subprogram of a visible
10120 -- abstract type is declared in a private part, then it must override
10121 -- an abstract subprogram declared in the visible part. Also checks
10122 -- that if a primitive function with a controlling result is declared
10123 -- in a private part, then it must override a function declared in
10124 -- the visible part.
10126 ------------------------------
10127 -- Check_Private_Overriding --
10128 ------------------------------
10130 procedure Check_Private_Overriding (T : Entity_Id) is
10131 function Overrides_Private_Part_Op return Boolean;
10132 -- This detects the special case where the overriding subprogram
10133 -- is overriding a subprogram that was declared in the same
10134 -- private part. That case is illegal by 3.9.3(10).
10136 function Overrides_Visible_Function
10137 (Partial_View : Entity_Id) return Boolean;
10138 -- True if S overrides a function in the visible part. The
10139 -- overridden function could be explicitly or implicitly declared.
10141 -------------------------------
10142 -- Overrides_Private_Part_Op --
10143 -------------------------------
10145 function Overrides_Private_Part_Op return Boolean is
10146 Over_Decl : constant Node_Id :=
10147 Unit_Declaration_Node (Overridden_Operation (S));
10148 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10151 pragma Assert (Is_Overriding);
10153 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10155 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10157 return In_Same_List (Over_Decl, Subp_Decl);
10158 end Overrides_Private_Part_Op;
10160 --------------------------------
10161 -- Overrides_Visible_Function --
10162 --------------------------------
10164 function Overrides_Visible_Function
10165 (Partial_View : Entity_Id) return Boolean
10168 if not Is_Overriding or else not Has_Homonym (S) then
10172 if not Present (Partial_View) then
10176 -- Search through all the homonyms H of S in the current
10177 -- package spec, and return True if we find one that matches.
10178 -- Note that Parent (H) will be the declaration of the
10179 -- partial view of T for a match.
10182 H : Entity_Id := S;
10186 exit when not Present (H) or else Scope (H) /= Scope (S);
10190 N_Private_Extension_Declaration,
10191 N_Private_Type_Declaration)
10192 and then Defining_Identifier (Parent (H)) = Partial_View
10200 end Overrides_Visible_Function;
10202 -- Start of processing for Check_Private_Overriding
10205 if Is_Package_Or_Generic_Package (Current_Scope)
10206 and then In_Private_Part (Current_Scope)
10207 and then Visible_Part_Type (T)
10208 and then not In_Instance
10210 if Is_Abstract_Type (T)
10211 and then Is_Abstract_Subprogram (S)
10212 and then (not Is_Overriding
10213 or else not Is_Abstract_Subprogram (E)
10214 or else Overrides_Private_Part_Op)
10217 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10220 elsif Ekind (S) = E_Function then
10222 Partial_View : constant Entity_Id :=
10223 Incomplete_Or_Partial_View (T);
10226 if not Overrides_Visible_Function (Partial_View) then
10228 -- Here, S is "function ... return T;" declared in
10229 -- the private part, not overriding some visible
10230 -- operation. That's illegal in the tagged case
10231 -- (but not if the private type is untagged).
10233 if ((Present (Partial_View)
10234 and then Is_Tagged_Type (Partial_View))
10235 or else (not Present (Partial_View)
10236 and then Is_Tagged_Type (T)))
10237 and then T = Base_Type (Etype (S))
10240 ("private function with tagged result must"
10241 & " override visible-part function", S);
10243 ("\move subprogram to the visible part"
10244 & " (RM 3.9.3(10))", S);
10246 -- AI05-0073: extend this test to the case of a
10247 -- function with a controlling access result.
10249 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10250 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10252 not Is_Class_Wide_Type
10253 (Designated_Type (Etype (S)))
10254 and then Ada_Version >= Ada_2012
10257 ("private function with controlling access "
10258 & "result must override visible-part function",
10261 ("\move subprogram to the visible part"
10262 & " (RM 3.9.3(10))", S);
10268 end Check_Private_Overriding;
10270 -----------------------
10271 -- Visible_Part_Type --
10272 -----------------------
10274 function Visible_Part_Type (T : Entity_Id) return Boolean is
10275 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10278 -- If the entity is a private type, then it must be declared in a
10281 if Ekind (T) in Private_Kind then
10284 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10287 elsif Is_List_Member (Declaration_Node (T))
10288 and then List_Containing (Declaration_Node (T)) =
10289 Visible_Declarations (Specification (P))
10296 end Visible_Part_Type;
10298 -- Start of processing for Check_For_Primitive_Subprogram
10301 Is_Primitive := False;
10303 if not Comes_From_Source (S) then
10306 -- If subprogram is at library level, it is not primitive operation
10308 elsif Current_Scope = Standard_Standard then
10311 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10312 and then not In_Package_Body (Current_Scope))
10313 or else Is_Overriding
10315 -- For function, check return type
10317 if Ekind (S) = E_Function then
10318 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10319 F_Typ := Designated_Type (Etype (S));
10321 F_Typ := Etype (S);
10324 B_Typ := Base_Type (F_Typ);
10326 if Scope (B_Typ) = Current_Scope
10327 and then not Is_Class_Wide_Type (B_Typ)
10328 and then not Is_Generic_Type (B_Typ)
10330 Is_Primitive := True;
10331 Set_Has_Primitive_Operations (B_Typ);
10332 Set_Is_Primitive (S);
10333 Check_Private_Overriding (B_Typ);
10335 -- The Ghost policy in effect at the point of declaration
10336 -- or a tagged type and a primitive operation must match
10337 -- (SPARK RM 6.9(16)).
10339 Check_Ghost_Primitive (S, B_Typ);
10343 -- For all subprograms, check formals
10345 Formal := First_Formal (S);
10346 while Present (Formal) loop
10347 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10348 F_Typ := Designated_Type (Etype (Formal));
10350 F_Typ := Etype (Formal);
10353 B_Typ := Base_Type (F_Typ);
10355 if Ekind (B_Typ) = E_Access_Subtype then
10356 B_Typ := Base_Type (B_Typ);
10359 if Scope (B_Typ) = Current_Scope
10360 and then not Is_Class_Wide_Type (B_Typ)
10361 and then not Is_Generic_Type (B_Typ)
10363 Is_Primitive := True;
10364 Set_Is_Primitive (S);
10365 Set_Has_Primitive_Operations (B_Typ);
10366 Check_Private_Overriding (B_Typ);
10368 -- The Ghost policy in effect at the point of declaration
10369 -- of a tagged type and a primitive operation must match
10370 -- (SPARK RM 6.9(16)).
10372 Check_Ghost_Primitive (S, B_Typ);
10375 Next_Formal (Formal);
10378 -- Special case: An equality function can be redefined for a type
10379 -- occurring in a declarative part, and won't otherwise be treated as
10380 -- a primitive because it doesn't occur in a package spec and doesn't
10381 -- override an inherited subprogram. It's important that we mark it
10382 -- primitive so it can be returned by Collect_Primitive_Operations
10383 -- and be used in composing the equality operation of later types
10384 -- that have a component of the type.
10386 elsif Chars (S) = Name_Op_Eq
10387 and then Etype (S) = Standard_Boolean
10389 B_Typ := Base_Type (Etype (First_Formal (S)));
10391 if Scope (B_Typ) = Current_Scope
10393 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10394 and then not Is_Limited_Type (B_Typ)
10396 Is_Primitive := True;
10397 Set_Is_Primitive (S);
10398 Set_Has_Primitive_Operations (B_Typ);
10399 Check_Private_Overriding (B_Typ);
10401 -- The Ghost policy in effect at the point of declaration of a
10402 -- tagged type and a primitive operation must match
10403 -- (SPARK RM 6.9(16)).
10405 Check_Ghost_Primitive (S, B_Typ);
10408 end Check_For_Primitive_Subprogram;
10410 --------------------------------------
10411 -- Has_Matching_Entry_Or_Subprogram --
10412 --------------------------------------
10414 function Has_Matching_Entry_Or_Subprogram
10415 (E : Entity_Id) return Boolean
10417 function Check_Conforming_Parameters
10418 (E1_Param : Node_Id;
10419 E2_Param : Node_Id) return Boolean;
10420 -- Starting from the given parameters, check that all the parameters
10421 -- of two entries or subprograms are subtype conformant. Used to skip
10422 -- the check on the controlling argument.
10424 function Matching_Entry_Or_Subprogram
10425 (Conc_Typ : Entity_Id;
10426 Subp : Entity_Id) return Entity_Id;
10427 -- Return the first entry or subprogram of the given concurrent type
10428 -- whose name matches the name of Subp and has a profile conformant
10429 -- with Subp; return Empty if not found.
10431 function Matching_Dispatching_Subprogram
10432 (Conc_Typ : Entity_Id;
10433 Ent : Entity_Id) return Entity_Id;
10434 -- Return the first dispatching primitive of Conc_Type defined in the
10435 -- enclosing scope of Conc_Type (i.e. before the full definition of
10436 -- this concurrent type) whose name matches the entry Ent and has a
10437 -- profile conformant with the profile of the corresponding (not yet
10438 -- built) dispatching primitive of Ent; return Empty if not found.
10440 function Matching_Original_Protected_Subprogram
10441 (Prot_Typ : Entity_Id;
10442 Subp : Entity_Id) return Entity_Id;
10443 -- Return the first subprogram defined in the enclosing scope of
10444 -- Prot_Typ (before the full definition of this protected type)
10445 -- whose name matches the original name of Subp and has a profile
10446 -- conformant with the profile of Subp; return Empty if not found.
10448 ---------------------------------
10449 -- Check_Conforming_Parameters --
10450 ---------------------------------
10452 function Check_Conforming_Parameters
10453 (E1_Param : Node_Id;
10454 E2_Param : Node_Id) return Boolean
10456 Param_E1 : Node_Id := E1_Param;
10457 Param_E2 : Node_Id := E2_Param;
10460 while Present (Param_E1) and then Present (Param_E2) loop
10461 if Ekind (Defining_Identifier (Param_E1)) /=
10462 Ekind (Defining_Identifier (Param_E2))
10465 (Find_Parameter_Type (Param_E1),
10466 Find_Parameter_Type (Param_E2),
10467 Subtype_Conformant)
10476 -- The candidate is not valid if one of the two lists contains
10477 -- more parameters than the other
10479 return No (Param_E1) and then No (Param_E2);
10480 end Check_Conforming_Parameters;
10482 ----------------------------------
10483 -- Matching_Entry_Or_Subprogram --
10484 ----------------------------------
10486 function Matching_Entry_Or_Subprogram
10487 (Conc_Typ : Entity_Id;
10488 Subp : Entity_Id) return Entity_Id
10493 E := First_Entity (Conc_Typ);
10494 while Present (E) loop
10495 if Chars (Subp) = Chars (E)
10496 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10498 Check_Conforming_Parameters
10499 (First (Parameter_Specifications (Parent (E))),
10500 Next (First (Parameter_Specifications (Parent (Subp)))))
10509 end Matching_Entry_Or_Subprogram;
10511 -------------------------------------
10512 -- Matching_Dispatching_Subprogram --
10513 -------------------------------------
10515 function Matching_Dispatching_Subprogram
10516 (Conc_Typ : Entity_Id;
10517 Ent : Entity_Id) return Entity_Id
10522 -- Search for entities in the enclosing scope of this synchonized
10525 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10526 Push_Scope (Scope (Conc_Typ));
10527 E := Current_Entity_In_Scope (Ent);
10530 while Present (E) loop
10531 if Scope (E) = Scope (Conc_Typ)
10532 and then Comes_From_Source (E)
10533 and then Ekind (E) = E_Procedure
10534 and then Present (First_Entity (E))
10535 and then Is_Controlling_Formal (First_Entity (E))
10536 and then Etype (First_Entity (E)) = Conc_Typ
10538 Check_Conforming_Parameters
10539 (First (Parameter_Specifications (Parent (Ent))),
10540 Next (First (Parameter_Specifications (Parent (E)))))
10549 end Matching_Dispatching_Subprogram;
10551 --------------------------------------------
10552 -- Matching_Original_Protected_Subprogram --
10553 --------------------------------------------
10555 function Matching_Original_Protected_Subprogram
10556 (Prot_Typ : Entity_Id;
10557 Subp : Entity_Id) return Entity_Id
10559 ICF : constant Boolean :=
10560 Is_Controlling_Formal (First_Entity (Subp));
10564 -- Temporarily decorate the first parameter of Subp as controlling
10565 -- formal, required to invoke Subtype_Conformant.
10567 Set_Is_Controlling_Formal (First_Entity (Subp));
10570 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10572 while Present (E) loop
10573 if Scope (E) = Scope (Prot_Typ)
10574 and then Comes_From_Source (E)
10575 and then Ekind (Subp) = Ekind (E)
10576 and then Present (First_Entity (E))
10577 and then Is_Controlling_Formal (First_Entity (E))
10578 and then Etype (First_Entity (E)) = Prot_Typ
10579 and then Subtype_Conformant (Subp, E,
10580 Skip_Controlling_Formals => True)
10582 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10589 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10592 end Matching_Original_Protected_Subprogram;
10594 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10597 -- Case 1: E is a subprogram whose first formal is a concurrent type
10598 -- defined in the scope of E that has an entry or subprogram whose
10599 -- profile matches E.
10601 if Comes_From_Source (E)
10602 and then Is_Subprogram (E)
10603 and then Present (First_Entity (E))
10604 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10607 Scope (Corresponding_Concurrent_Type
10608 (Etype (First_Entity (E))))
10611 (Matching_Entry_Or_Subprogram
10612 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10615 Report_Conflict (E,
10616 Matching_Entry_Or_Subprogram
10617 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10622 -- Case 2: E is an internally built dispatching subprogram of a
10623 -- protected type and there is a subprogram defined in the enclosing
10624 -- scope of the protected type that has the original name of E and
10625 -- its profile is conformant with the profile of E. We check the
10626 -- name of the original protected subprogram associated with E since
10627 -- the expander builds dispatching primitives of protected functions
10628 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10630 elsif not Comes_From_Source (E)
10631 and then Is_Subprogram (E)
10632 and then Present (First_Entity (E))
10633 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10634 and then Present (Original_Protected_Subprogram (E))
10637 (Matching_Original_Protected_Subprogram
10638 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10641 Report_Conflict (E,
10642 Matching_Original_Protected_Subprogram
10643 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10647 -- Case 3: E is an entry of a synchronized type and a matching
10648 -- procedure has been previously defined in the enclosing scope
10649 -- of the synchronized type.
10651 elsif Comes_From_Source (E)
10652 and then Ekind (E) = E_Entry
10654 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10656 Report_Conflict (E,
10657 Matching_Dispatching_Subprogram (Current_Scope, E));
10662 end Has_Matching_Entry_Or_Subprogram;
10664 ----------------------------
10665 -- Is_Private_Declaration --
10666 ----------------------------
10668 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10669 Decl : constant Node_Id := Unit_Declaration_Node (E);
10670 Priv_Decls : List_Id;
10673 if Is_Package_Or_Generic_Package (Current_Scope)
10674 and then In_Private_Part (Current_Scope)
10677 Private_Declarations (Package_Specification (Current_Scope));
10679 return In_Package_Body (Current_Scope)
10681 (Is_List_Member (Decl)
10682 and then List_Containing (Decl) = Priv_Decls)
10683 or else (Nkind (Parent (Decl)) = N_Package_Specification
10685 Is_Compilation_Unit
10686 (Defining_Entity (Parent (Decl)))
10687 and then List_Containing (Parent (Parent (Decl))) =
10692 end Is_Private_Declaration;
10694 --------------------------
10695 -- Is_Overriding_Alias --
10696 --------------------------
10698 function Is_Overriding_Alias
10699 (Old_E : Entity_Id;
10700 New_E : Entity_Id) return Boolean
10702 AO : constant Entity_Id := Alias (Old_E);
10703 AN : constant Entity_Id := Alias (New_E);
10706 return Scope (AO) /= Scope (AN)
10707 or else No (DTC_Entity (AO))
10708 or else No (DTC_Entity (AN))
10709 or else DT_Position (AO) = DT_Position (AN);
10710 end Is_Overriding_Alias;
10712 ---------------------
10713 -- Report_Conflict --
10714 ---------------------
10716 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10718 Error_Msg_Sloc := Sloc (E);
10720 -- Generate message, with useful additional warning if in generic
10722 if Is_Generic_Unit (E) then
10723 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10724 Error_Msg_N ("\& conflicts with declaration#", S);
10726 Error_Msg_N ("& conflicts with declaration#", S);
10728 end Report_Conflict;
10730 -- Start of processing for New_Overloaded_Entity
10733 -- We need to look for an entity that S may override. This must be a
10734 -- homonym in the current scope, so we look for the first homonym of
10735 -- S in the current scope as the starting point for the search.
10737 E := Current_Entity_In_Scope (S);
10739 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10740 -- They are directly added to the list of primitive operations of
10741 -- Derived_Type, unless this is a rederivation in the private part
10742 -- of an operation that was already derived in the visible part of
10743 -- the current package.
10745 if Ada_Version >= Ada_2005
10746 and then Present (Derived_Type)
10747 and then Present (Alias (S))
10748 and then Is_Dispatching_Operation (Alias (S))
10749 and then Present (Find_Dispatching_Type (Alias (S)))
10750 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10752 -- For private types, when the full-view is processed we propagate to
10753 -- the full view the non-overridden entities whose attribute "alias"
10754 -- references an interface primitive. These entities were added by
10755 -- Derive_Subprograms to ensure that interface primitives are
10758 -- Inside_Freeze_Actions is non zero when S corresponds with an
10759 -- internal entity that links an interface primitive with its
10760 -- covering primitive through attribute Interface_Alias (see
10761 -- Add_Internal_Interface_Entities).
10763 if Inside_Freezing_Actions = 0
10764 and then Is_Package_Or_Generic_Package (Current_Scope)
10765 and then In_Private_Part (Current_Scope)
10766 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10767 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10768 and then Full_View (Defining_Identifier (Parent (E)))
10769 = Defining_Identifier (Parent (S))
10770 and then Alias (E) = Alias (S)
10772 Check_Operation_From_Private_View (S, E);
10773 Set_Is_Dispatching_Operation (S);
10778 Enter_Overloaded_Entity (S);
10779 Check_Dispatching_Operation (S, Empty);
10780 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10786 -- For synchronized types check conflicts of this entity with previously
10787 -- defined entities.
10789 if Ada_Version >= Ada_2005
10790 and then Has_Matching_Entry_Or_Subprogram (S)
10795 -- If there is no homonym then this is definitely not overriding
10798 Enter_Overloaded_Entity (S);
10799 Check_Dispatching_Operation (S, Empty);
10800 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10802 -- If subprogram has an explicit declaration, check whether it has an
10803 -- overriding indicator.
10805 if Comes_From_Source (S) then
10806 Check_Synchronized_Overriding (S, Overridden_Subp);
10808 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10809 -- it may have overridden some hidden inherited primitive. Update
10810 -- Overridden_Subp to avoid spurious errors when checking the
10811 -- overriding indicator.
10813 if Ada_Version >= Ada_2012
10814 and then No (Overridden_Subp)
10815 and then Is_Dispatching_Operation (S)
10816 and then Present (Overridden_Operation (S))
10818 Overridden_Subp := Overridden_Operation (S);
10821 Check_Overriding_Indicator
10822 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10824 -- The Ghost policy in effect at the point of declaration of a
10825 -- parent subprogram and an overriding subprogram must match
10826 -- (SPARK RM 6.9(17)).
10828 Check_Ghost_Overriding (S, Overridden_Subp);
10831 -- If there is a homonym that is not overloadable, then we have an
10832 -- error, except for the special cases checked explicitly below.
10834 elsif not Is_Overloadable (E) then
10836 -- Check for spurious conflict produced by a subprogram that has the
10837 -- same name as that of the enclosing generic package. The conflict
10838 -- occurs within an instance, between the subprogram and the renaming
10839 -- declaration for the package. After the subprogram, the package
10840 -- renaming declaration becomes hidden.
10842 if Ekind (E) = E_Package
10843 and then Present (Renamed_Object (E))
10844 and then Renamed_Object (E) = Current_Scope
10845 and then Nkind (Parent (Renamed_Object (E))) =
10846 N_Package_Specification
10847 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10850 Set_Is_Immediately_Visible (E, False);
10851 Enter_Overloaded_Entity (S);
10852 Set_Homonym (S, Homonym (E));
10853 Check_Dispatching_Operation (S, Empty);
10854 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10856 -- If the subprogram is implicit it is hidden by the previous
10857 -- declaration. However if it is dispatching, it must appear in the
10858 -- dispatch table anyway, because it can be dispatched to even if it
10859 -- cannot be called directly.
10861 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10862 Set_Scope (S, Current_Scope);
10864 if Is_Dispatching_Operation (Alias (S)) then
10865 Check_Dispatching_Operation (S, Empty);
10871 Report_Conflict (S, E);
10875 -- E exists and is overloadable
10878 Check_Synchronized_Overriding (S, Overridden_Subp);
10880 -- Loop through E and its homonyms to determine if any of them is
10881 -- the candidate for overriding by S.
10883 while Present (E) loop
10885 -- Definitely not interesting if not in the current scope
10887 if Scope (E) /= Current_Scope then
10890 -- A function can overload the name of an abstract state. The
10891 -- state can be viewed as a function with a profile that cannot
10892 -- be matched by anything.
10894 elsif Ekind (S) = E_Function
10895 and then Ekind (E) = E_Abstract_State
10897 Enter_Overloaded_Entity (S);
10900 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10901 -- procedures locate the internally generated spec. We enforce
10902 -- mode conformance since a tagged type may inherit from
10903 -- interfaces several null primitives which differ only in
10904 -- the mode of the formals.
10906 elsif not Comes_From_Source (S)
10907 and then Is_Null_Procedure (S)
10908 and then not Mode_Conformant (E, S)
10912 -- Check if we have type conformance
10914 elsif Type_Conformant (E, S) then
10916 -- If the old and new entities have the same profile and one
10917 -- is not the body of the other, then this is an error, unless
10918 -- one of them is implicitly declared.
10920 -- There are some cases when both can be implicit, for example
10921 -- when both a literal and a function that overrides it are
10922 -- inherited in a derivation, or when an inherited operation
10923 -- of a tagged full type overrides the inherited operation of
10924 -- a private extension. Ada 83 had a special rule for the
10925 -- literal case. In Ada 95, the later implicit operation hides
10926 -- the former, and the literal is always the former. In the
10927 -- odd case where both are derived operations declared at the
10928 -- same point, both operations should be declared, and in that
10929 -- case we bypass the following test and proceed to the next
10930 -- part. This can only occur for certain obscure cases in
10931 -- instances, when an operation on a type derived from a formal
10932 -- private type does not override a homograph inherited from
10933 -- the actual. In subsequent derivations of such a type, the
10934 -- DT positions of these operations remain distinct, if they
10937 if Present (Alias (S))
10938 and then (No (Alias (E))
10939 or else Comes_From_Source (E)
10940 or else Is_Abstract_Subprogram (S)
10942 (Is_Dispatching_Operation (E)
10943 and then Is_Overriding_Alias (E, S)))
10944 and then Ekind (E) /= E_Enumeration_Literal
10946 -- When an derived operation is overloaded it may be due to
10947 -- the fact that the full view of a private extension
10948 -- re-inherits. It has to be dealt with.
10950 if Is_Package_Or_Generic_Package (Current_Scope)
10951 and then In_Private_Part (Current_Scope)
10953 Check_Operation_From_Private_View (S, E);
10956 -- In any case the implicit operation remains hidden by the
10957 -- existing declaration, which is overriding. Indicate that
10958 -- E overrides the operation from which S is inherited.
10960 if Present (Alias (S)) then
10961 Set_Overridden_Operation (E, Alias (S));
10962 Inherit_Subprogram_Contract (E, Alias (S));
10965 Set_Overridden_Operation (E, S);
10966 Inherit_Subprogram_Contract (E, S);
10969 if Comes_From_Source (E) then
10970 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10972 -- The Ghost policy in effect at the point of declaration
10973 -- of a parent subprogram and an overriding subprogram
10974 -- must match (SPARK RM 6.9(17)).
10976 Check_Ghost_Overriding (E, S);
10981 -- Within an instance, the renaming declarations for actual
10982 -- subprograms may become ambiguous, but they do not hide each
10985 elsif Ekind (E) /= E_Entry
10986 and then not Comes_From_Source (E)
10987 and then not Is_Generic_Instance (E)
10988 and then (Present (Alias (E))
10989 or else Is_Intrinsic_Subprogram (E))
10990 and then (not In_Instance
10991 or else No (Parent (E))
10992 or else Nkind (Unit_Declaration_Node (E)) /=
10993 N_Subprogram_Renaming_Declaration)
10995 -- A subprogram child unit is not allowed to override an
10996 -- inherited subprogram (10.1.1(20)).
10998 if Is_Child_Unit (S) then
11000 ("child unit overrides inherited subprogram in parent",
11005 if Is_Non_Overriding_Operation (E, S) then
11006 Enter_Overloaded_Entity (S);
11008 if No (Derived_Type)
11009 or else Is_Tagged_Type (Derived_Type)
11011 Check_Dispatching_Operation (S, Empty);
11017 -- E is a derived operation or an internal operator which
11018 -- is being overridden. Remove E from further visibility.
11019 -- Furthermore, if E is a dispatching operation, it must be
11020 -- replaced in the list of primitive operations of its type
11021 -- (see Override_Dispatching_Operation).
11023 Overridden_Subp := E;
11029 Prev := First_Entity (Current_Scope);
11030 while Present (Prev) and then Next_Entity (Prev) /= E loop
11031 Next_Entity (Prev);
11034 -- It is possible for E to be in the current scope and
11035 -- yet not in the entity chain. This can only occur in a
11036 -- generic context where E is an implicit concatenation
11037 -- in the formal part, because in a generic body the
11038 -- entity chain starts with the formals.
11040 -- In GNATprove mode, a wrapper for an operation with
11041 -- axiomatization may be a homonym of another declaration
11042 -- for an actual subprogram (needs refinement ???).
11046 and then GNATprove_Mode
11048 Nkind (Original_Node (Unit_Declaration_Node (S))) =
11049 N_Subprogram_Renaming_Declaration
11053 pragma Assert (Chars (E) = Name_Op_Concat);
11058 -- E must be removed both from the entity_list of the
11059 -- current scope, and from the visibility chain.
11061 if Debug_Flag_E then
11062 Write_Str ("Override implicit operation ");
11063 Write_Int (Int (E));
11067 -- If E is a predefined concatenation, it stands for four
11068 -- different operations. As a result, a single explicit
11069 -- declaration does not hide it. In a possible ambiguous
11070 -- situation, Disambiguate chooses the user-defined op,
11071 -- so it is correct to retain the previous internal one.
11073 if Chars (E) /= Name_Op_Concat
11074 or else Ekind (E) /= E_Operator
11076 -- For nondispatching derived operations that are
11077 -- overridden by a subprogram declared in the private
11078 -- part of a package, we retain the derived subprogram
11079 -- but mark it as not immediately visible. If the
11080 -- derived operation was declared in the visible part
11081 -- then this ensures that it will still be visible
11082 -- outside the package with the proper signature
11083 -- (calls from outside must also be directed to this
11084 -- version rather than the overriding one, unlike the
11085 -- dispatching case). Calls from inside the package
11086 -- will still resolve to the overriding subprogram
11087 -- since the derived one is marked as not visible
11088 -- within the package.
11090 -- If the private operation is dispatching, we achieve
11091 -- the overriding by keeping the implicit operation
11092 -- but setting its alias to be the overriding one. In
11093 -- this fashion the proper body is executed in all
11094 -- cases, but the original signature is used outside
11097 -- If the overriding is not in the private part, we
11098 -- remove the implicit operation altogether.
11100 if Is_Private_Declaration (S) then
11101 if not Is_Dispatching_Operation (E) then
11102 Set_Is_Immediately_Visible (E, False);
11104 -- Work done in Override_Dispatching_Operation,
11105 -- so nothing else needs to be done here.
11111 -- Find predecessor of E in Homonym chain
11113 if E = Current_Entity (E) then
11116 Prev_Vis := Current_Entity (E);
11117 while Homonym (Prev_Vis) /= E loop
11118 Prev_Vis := Homonym (Prev_Vis);
11122 if Prev_Vis /= Empty then
11124 -- Skip E in the visibility chain
11126 Set_Homonym (Prev_Vis, Homonym (E));
11129 Set_Name_Entity_Id (Chars (E), Homonym (E));
11132 Set_Next_Entity (Prev, Next_Entity (E));
11134 if No (Next_Entity (Prev)) then
11135 Set_Last_Entity (Current_Scope, Prev);
11140 Enter_Overloaded_Entity (S);
11142 -- For entities generated by Derive_Subprograms the
11143 -- overridden operation is the inherited primitive
11144 -- (which is available through the attribute alias).
11146 if not (Comes_From_Source (E))
11147 and then Is_Dispatching_Operation (E)
11148 and then Find_Dispatching_Type (E) =
11149 Find_Dispatching_Type (S)
11150 and then Present (Alias (E))
11151 and then Comes_From_Source (Alias (E))
11153 Set_Overridden_Operation (S, Alias (E));
11154 Inherit_Subprogram_Contract (S, Alias (E));
11156 -- Normal case of setting entity as overridden
11158 -- Note: Static_Initialization and Overridden_Operation
11159 -- attributes use the same field in subprogram entities.
11160 -- Static_Initialization is only defined for internal
11161 -- initialization procedures, where Overridden_Operation
11162 -- is irrelevant. Therefore the setting of this attribute
11163 -- must check whether the target is an init_proc.
11165 elsif not Is_Init_Proc (S) then
11166 Set_Overridden_Operation (S, E);
11167 Inherit_Subprogram_Contract (S, E);
11170 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11172 -- The Ghost policy in effect at the point of declaration
11173 -- of a parent subprogram and an overriding subprogram
11174 -- must match (SPARK RM 6.9(17)).
11176 Check_Ghost_Overriding (S, E);
11178 -- If S is a user-defined subprogram or a null procedure
11179 -- expanded to override an inherited null procedure, or a
11180 -- predefined dispatching primitive then indicate that E
11181 -- overrides the operation from which S is inherited.
11183 if Comes_From_Source (S)
11185 (Present (Parent (S))
11187 Nkind (Parent (S)) = N_Procedure_Specification
11189 Null_Present (Parent (S)))
11191 (Present (Alias (E))
11193 Is_Predefined_Dispatching_Operation (Alias (E)))
11195 if Present (Alias (E)) then
11196 Set_Overridden_Operation (S, Alias (E));
11197 Inherit_Subprogram_Contract (S, Alias (E));
11201 if Is_Dispatching_Operation (E) then
11203 -- An overriding dispatching subprogram inherits the
11204 -- convention of the overridden subprogram (AI-117).
11206 Set_Convention (S, Convention (E));
11207 Check_Dispatching_Operation (S, E);
11210 Check_Dispatching_Operation (S, Empty);
11213 Check_For_Primitive_Subprogram
11214 (Is_Primitive_Subp, Is_Overriding => True);
11215 goto Check_Inequality;
11218 -- Apparent redeclarations in instances can occur when two
11219 -- formal types get the same actual type. The subprograms in
11220 -- in the instance are legal, even if not callable from the
11221 -- outside. Calls from within are disambiguated elsewhere.
11222 -- For dispatching operations in the visible part, the usual
11223 -- rules apply, and operations with the same profile are not
11224 -- legal (B830001).
11226 elsif (In_Instance_Visible_Part
11227 and then not Is_Dispatching_Operation (E))
11228 or else In_Instance_Not_Visible
11232 -- Here we have a real error (identical profile)
11235 Error_Msg_Sloc := Sloc (E);
11237 -- Avoid cascaded errors if the entity appears in
11238 -- subsequent calls.
11240 Set_Scope (S, Current_Scope);
11242 -- Generate error, with extra useful warning for the case
11243 -- of a generic instance with no completion.
11245 if Is_Generic_Instance (S)
11246 and then not Has_Completion (E)
11249 ("instantiation cannot provide body for&", S);
11250 Error_Msg_N ("\& conflicts with declaration#", S);
11252 Error_Msg_N ("& conflicts with declaration#", S);
11259 -- If one subprogram has an access parameter and the other
11260 -- a parameter of an access type, calls to either might be
11261 -- ambiguous. Verify that parameters match except for the
11262 -- access parameter.
11264 if May_Hide_Profile then
11270 F1 := First_Formal (S);
11271 F2 := First_Formal (E);
11272 while Present (F1) and then Present (F2) loop
11273 if Is_Access_Type (Etype (F1)) then
11274 if not Is_Access_Type (Etype (F2))
11275 or else not Conforming_Types
11276 (Designated_Type (Etype (F1)),
11277 Designated_Type (Etype (F2)),
11280 May_Hide_Profile := False;
11284 not Conforming_Types
11285 (Etype (F1), Etype (F2), Type_Conformant)
11287 May_Hide_Profile := False;
11294 if May_Hide_Profile
11298 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11307 -- On exit, we know that S is a new entity
11309 Enter_Overloaded_Entity (S);
11310 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11311 Check_Overriding_Indicator
11312 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11314 -- The Ghost policy in effect at the point of declaration of a parent
11315 -- subprogram and an overriding subprogram must match
11316 -- (SPARK RM 6.9(17)).
11318 Check_Ghost_Overriding (S, Overridden_Subp);
11320 -- Overloading is not allowed in SPARK, except for operators
11322 if Nkind (S) /= N_Defining_Operator_Symbol then
11323 Error_Msg_Sloc := Sloc (Homonym (S));
11324 Check_SPARK_05_Restriction
11325 ("overloading not allowed with entity#", S);
11328 -- If S is a derived operation for an untagged type then by
11329 -- definition it's not a dispatching operation (even if the parent
11330 -- operation was dispatching), so Check_Dispatching_Operation is not
11331 -- called in that case.
11333 if No (Derived_Type)
11334 or else Is_Tagged_Type (Derived_Type)
11336 Check_Dispatching_Operation (S, Empty);
11340 -- If this is a user-defined equality operator that is not a derived
11341 -- subprogram, create the corresponding inequality. If the operation is
11342 -- dispatching, the expansion is done elsewhere, and we do not create
11343 -- an explicit inequality operation.
11345 <<Check_Inequality>>
11346 if Chars (S) = Name_Op_Eq
11347 and then Etype (S) = Standard_Boolean
11348 and then Present (Parent (S))
11349 and then not Is_Dispatching_Operation (S)
11351 Make_Inequality_Operator (S);
11352 Check_Untagged_Equality (S);
11354 end New_Overloaded_Entity;
11356 ---------------------
11357 -- Process_Formals --
11358 ---------------------
11360 procedure Process_Formals
11362 Related_Nod : Node_Id)
11364 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11365 -- Determine whether an access type designates a type coming from a
11368 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11369 -- Check whether the default has a class-wide type. After analysis the
11370 -- default has the type of the formal, so we must also check explicitly
11371 -- for an access attribute.
11373 ----------------------------------
11374 -- Designates_From_Limited_With --
11375 ----------------------------------
11377 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11378 Desig : Entity_Id := Typ;
11381 if Is_Access_Type (Desig) then
11382 Desig := Directly_Designated_Type (Desig);
11385 if Is_Class_Wide_Type (Desig) then
11386 Desig := Root_Type (Desig);
11390 Ekind (Desig) = E_Incomplete_Type
11391 and then From_Limited_With (Desig);
11392 end Designates_From_Limited_With;
11394 ---------------------------
11395 -- Is_Class_Wide_Default --
11396 ---------------------------
11398 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11400 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11401 or else (Nkind (D) = N_Attribute_Reference
11402 and then Attribute_Name (D) = Name_Access
11403 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11404 end Is_Class_Wide_Default;
11408 Context : constant Node_Id := Parent (Parent (T));
11410 Formal : Entity_Id;
11411 Formal_Type : Entity_Id;
11412 Param_Spec : Node_Id;
11415 Num_Out_Params : Nat := 0;
11416 First_Out_Param : Entity_Id := Empty;
11417 -- Used for setting Is_Only_Out_Parameter
11419 -- Start of processing for Process_Formals
11422 -- In order to prevent premature use of the formals in the same formal
11423 -- part, the Ekind is left undefined until all default expressions are
11424 -- analyzed. The Ekind is established in a separate loop at the end.
11426 Param_Spec := First (T);
11427 while Present (Param_Spec) loop
11428 Formal := Defining_Identifier (Param_Spec);
11429 Set_Never_Set_In_Source (Formal, True);
11430 Enter_Name (Formal);
11432 -- Case of ordinary parameters
11434 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11435 Find_Type (Parameter_Type (Param_Spec));
11436 Ptype := Parameter_Type (Param_Spec);
11438 if Ptype = Error then
11442 Formal_Type := Entity (Ptype);
11444 if Is_Incomplete_Type (Formal_Type)
11446 (Is_Class_Wide_Type (Formal_Type)
11447 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11449 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11450 -- primitive operations, as long as their completion is
11451 -- in the same declarative part. If in the private part
11452 -- this means that the type cannot be a Taft-amendment type.
11453 -- Check is done on package exit. For access to subprograms,
11454 -- the use is legal for Taft-amendment types.
11456 -- Ada 2012: tagged incomplete types are allowed as generic
11457 -- formal types. They do not introduce dependencies and the
11458 -- corresponding generic subprogram does not have a delayed
11459 -- freeze, because it does not need a freeze node. However,
11460 -- it is still the case that untagged incomplete types cannot
11461 -- be Taft-amendment types and must be completed in private
11462 -- part, so the subprogram must appear in the list of private
11463 -- dependents of the type.
11465 if Is_Tagged_Type (Formal_Type)
11466 or else (Ada_Version >= Ada_2012
11467 and then not From_Limited_With (Formal_Type)
11468 and then not Is_Generic_Type (Formal_Type))
11470 if Ekind (Scope (Current_Scope)) = E_Package
11471 and then not Is_Generic_Type (Formal_Type)
11472 and then not Is_Class_Wide_Type (Formal_Type)
11475 (Parent (T), N_Access_Function_Definition,
11476 N_Access_Procedure_Definition)
11478 Append_Elmt (Current_Scope,
11479 Private_Dependents (Base_Type (Formal_Type)));
11481 -- Freezing is delayed to ensure that Register_Prim
11482 -- will get called for this operation, which is needed
11483 -- in cases where static dispatch tables aren't built.
11484 -- (Note that the same is done for controlling access
11485 -- parameter cases in function Access_Definition.)
11487 if not Is_Thunk (Current_Scope) then
11488 Set_Has_Delayed_Freeze (Current_Scope);
11493 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11494 N_Access_Procedure_Definition)
11496 -- AI05-0151: Tagged incomplete types are allowed in all
11497 -- formal parts. Untagged incomplete types are not allowed
11498 -- in bodies. Limited views of either kind are not allowed
11499 -- if there is no place at which the non-limited view can
11500 -- become available.
11502 -- Incomplete formal untagged types are not allowed in
11503 -- subprogram bodies (but are legal in their declarations).
11504 -- This excludes bodies created for null procedures, which
11505 -- are basic declarations.
11507 if Is_Generic_Type (Formal_Type)
11508 and then not Is_Tagged_Type (Formal_Type)
11509 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11512 ("invalid use of formal incomplete type", Param_Spec);
11514 elsif Ada_Version >= Ada_2012 then
11515 if Is_Tagged_Type (Formal_Type)
11516 and then (not From_Limited_With (Formal_Type)
11517 or else not In_Package_Body)
11521 elsif Nkind_In (Context, N_Accept_Statement,
11522 N_Accept_Alternative,
11524 or else (Nkind (Context) = N_Subprogram_Body
11525 and then Comes_From_Source (Context))
11528 ("invalid use of untagged incomplete type &",
11529 Ptype, Formal_Type);
11534 ("invalid use of incomplete type&",
11535 Param_Spec, Formal_Type);
11537 -- Further checks on the legality of incomplete types
11538 -- in formal parts are delayed until the freeze point
11539 -- of the enclosing subprogram or access to subprogram.
11543 elsif Ekind (Formal_Type) = E_Void then
11545 ("premature use of&",
11546 Parameter_Type (Param_Spec), Formal_Type);
11549 -- Ada 2012 (AI-142): Handle aliased parameters
11551 if Ada_Version >= Ada_2012
11552 and then Aliased_Present (Param_Spec)
11554 Set_Is_Aliased (Formal);
11557 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11558 -- declaration corresponding to the null-excluding type of the
11559 -- formal in the enclosing scope. Finally, replace the parameter
11560 -- type of the formal with the internal subtype.
11562 if Ada_Version >= Ada_2005
11563 and then Null_Exclusion_Present (Param_Spec)
11565 if not Is_Access_Type (Formal_Type) then
11567 ("`NOT NULL` allowed only for an access type", Param_Spec);
11570 if Can_Never_Be_Null (Formal_Type)
11571 and then Comes_From_Source (Related_Nod)
11574 ("`NOT NULL` not allowed (& already excludes null)",
11575 Param_Spec, Formal_Type);
11579 Create_Null_Excluding_Itype
11581 Related_Nod => Related_Nod,
11582 Scope_Id => Scope (Current_Scope));
11584 -- If the designated type of the itype is an itype that is
11585 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11586 -- on the access subtype, to prevent order-of-elaboration
11587 -- issues in the backend.
11590 -- type T is access procedure;
11591 -- procedure Op (O : not null T);
11593 if Is_Itype (Directly_Designated_Type (Formal_Type))
11595 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11597 Set_Has_Delayed_Freeze (Formal_Type);
11602 -- An access formal type
11606 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11608 -- No need to continue if we already notified errors
11610 if not Present (Formal_Type) then
11614 -- Ada 2005 (AI-254)
11617 AD : constant Node_Id :=
11618 Access_To_Subprogram_Definition
11619 (Parameter_Type (Param_Spec));
11621 if Present (AD) and then Protected_Present (AD) then
11623 Replace_Anonymous_Access_To_Protected_Subprogram
11629 Set_Etype (Formal, Formal_Type);
11631 -- Deal with default expression if present
11633 Default := Expression (Param_Spec);
11635 if Present (Default) then
11636 Check_SPARK_05_Restriction
11637 ("default expression is not allowed", Default);
11639 if Out_Present (Param_Spec) then
11641 ("default initialization only allowed for IN parameters",
11645 -- Do the special preanalysis of the expression (see section on
11646 -- "Handling of Default Expressions" in the spec of package Sem).
11648 Preanalyze_Spec_Expression (Default, Formal_Type);
11650 -- An access to constant cannot be the default for
11651 -- an access parameter that is an access to variable.
11653 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11654 and then not Is_Access_Constant (Formal_Type)
11655 and then Is_Access_Type (Etype (Default))
11656 and then Is_Access_Constant (Etype (Default))
11659 ("formal that is access to variable cannot be initialized "
11660 & "with an access-to-constant expression", Default);
11663 -- Check that the designated type of an access parameter's default
11664 -- is not a class-wide type unless the parameter's designated type
11665 -- is also class-wide.
11667 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11668 and then not Designates_From_Limited_With (Formal_Type)
11669 and then Is_Class_Wide_Default (Default)
11670 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11673 ("access to class-wide expression not allowed here", Default);
11676 -- Check incorrect use of dynamically tagged expressions
11678 if Is_Tagged_Type (Formal_Type) then
11679 Check_Dynamically_Tagged_Expression
11681 Typ => Formal_Type,
11682 Related_Nod => Default);
11686 -- Ada 2005 (AI-231): Static checks
11688 if Ada_Version >= Ada_2005
11689 and then Is_Access_Type (Etype (Formal))
11690 and then Can_Never_Be_Null (Etype (Formal))
11692 Null_Exclusion_Static_Checks (Param_Spec);
11695 -- The following checks are relevant only when SPARK_Mode is on as
11696 -- these are not standard Ada legality rules.
11698 if SPARK_Mode = On then
11699 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11701 -- A function cannot have a parameter of mode IN OUT or OUT
11704 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11706 ("function cannot have parameter of mode `OUT` or "
11707 & "`IN OUT`", Formal);
11710 -- A procedure cannot have an effectively volatile formal
11711 -- parameter of mode IN because it behaves as a constant
11712 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11714 elsif Ekind (Scope (Formal)) = E_Procedure
11715 and then Ekind (Formal) = E_In_Parameter
11716 and then Is_Effectively_Volatile (Formal)
11719 ("formal parameter of mode `IN` cannot be volatile", Formal);
11727 -- If this is the formal part of a function specification, analyze the
11728 -- subtype mark in the context where the formals are visible but not
11729 -- yet usable, and may hide outer homographs.
11731 if Nkind (Related_Nod) = N_Function_Specification then
11732 Analyze_Return_Type (Related_Nod);
11735 -- Now set the kind (mode) of each formal
11737 Param_Spec := First (T);
11738 while Present (Param_Spec) loop
11739 Formal := Defining_Identifier (Param_Spec);
11740 Set_Formal_Mode (Formal);
11742 if Ekind (Formal) = E_In_Parameter then
11743 Set_Default_Value (Formal, Expression (Param_Spec));
11745 if Present (Expression (Param_Spec)) then
11746 Default := Expression (Param_Spec);
11748 if Is_Scalar_Type (Etype (Default)) then
11749 if Nkind (Parameter_Type (Param_Spec)) /=
11750 N_Access_Definition
11752 Formal_Type := Entity (Parameter_Type (Param_Spec));
11756 (Related_Nod, Parameter_Type (Param_Spec));
11759 Apply_Scalar_Range_Check (Default, Formal_Type);
11763 elsif Ekind (Formal) = E_Out_Parameter then
11764 Num_Out_Params := Num_Out_Params + 1;
11766 if Num_Out_Params = 1 then
11767 First_Out_Param := Formal;
11770 elsif Ekind (Formal) = E_In_Out_Parameter then
11771 Num_Out_Params := Num_Out_Params + 1;
11774 -- Skip remaining processing if formal type was in error
11776 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11777 goto Next_Parameter;
11780 -- Force call by reference if aliased
11783 Conv : constant Convention_Id := Convention (Etype (Formal));
11785 if Is_Aliased (Formal) then
11786 Set_Mechanism (Formal, By_Reference);
11788 -- Warn if user asked this to be passed by copy
11790 if Conv = Convention_Ada_Pass_By_Copy then
11792 ("cannot pass aliased parameter & by copy??", Formal);
11795 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11797 elsif Conv = Convention_Ada_Pass_By_Copy then
11798 Set_Mechanism (Formal, By_Copy);
11800 elsif Conv = Convention_Ada_Pass_By_Reference then
11801 Set_Mechanism (Formal, By_Reference);
11809 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11810 Set_Is_Only_Out_Parameter (First_Out_Param);
11812 end Process_Formals;
11814 ----------------------------
11815 -- Reference_Body_Formals --
11816 ----------------------------
11818 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11823 if Error_Posted (Spec) then
11827 -- Iterate over both lists. They may be of different lengths if the two
11828 -- specs are not conformant.
11830 Fs := First_Formal (Spec);
11831 Fb := First_Formal (Bod);
11832 while Present (Fs) and then Present (Fb) loop
11833 Generate_Reference (Fs, Fb, 'b');
11835 if Style_Check then
11836 Style.Check_Identifier (Fb, Fs);
11839 Set_Spec_Entity (Fb, Fs);
11840 Set_Referenced (Fs, False);
11844 end Reference_Body_Formals;
11846 -------------------------
11847 -- Set_Actual_Subtypes --
11848 -------------------------
11850 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11852 Formal : Entity_Id;
11854 First_Stmt : Node_Id := Empty;
11855 AS_Needed : Boolean;
11858 -- If this is an empty initialization procedure, no need to create
11859 -- actual subtypes (small optimization).
11861 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11864 -- Within a predicate function we do not want to generate local
11865 -- subtypes that may generate nested predicate functions.
11867 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11871 -- The subtype declarations may freeze the formals. The body generated
11872 -- for an expression function is not a freeze point, so do not emit
11873 -- these declarations (small loss of efficiency in rare cases).
11875 if Nkind (N) = N_Subprogram_Body
11876 and then Was_Expression_Function (N)
11881 Formal := First_Formal (Subp);
11882 while Present (Formal) loop
11883 T := Etype (Formal);
11885 -- We never need an actual subtype for a constrained formal
11887 if Is_Constrained (T) then
11888 AS_Needed := False;
11890 -- If we have unknown discriminants, then we do not need an actual
11891 -- subtype, or more accurately we cannot figure it out. Note that
11892 -- all class-wide types have unknown discriminants.
11894 elsif Has_Unknown_Discriminants (T) then
11895 AS_Needed := False;
11897 -- At this stage we have an unconstrained type that may need an
11898 -- actual subtype. For sure the actual subtype is needed if we have
11899 -- an unconstrained array type. However, in an instance, the type
11900 -- may appear as a subtype of the full view, while the actual is
11901 -- in fact private (in which case no actual subtype is needed) so
11902 -- check the kind of the base type.
11904 elsif Is_Array_Type (Base_Type (T)) then
11907 -- The only other case needing an actual subtype is an unconstrained
11908 -- record type which is an IN parameter (we cannot generate actual
11909 -- subtypes for the OUT or IN OUT case, since an assignment can
11910 -- change the discriminant values. However we exclude the case of
11911 -- initialization procedures, since discriminants are handled very
11912 -- specially in this context, see the section entitled "Handling of
11913 -- Discriminants" in Einfo.
11915 -- We also exclude the case of Discrim_SO_Functions (functions used
11916 -- in front-end layout mode for size/offset values), since in such
11917 -- functions only discriminants are referenced, and not only are such
11918 -- subtypes not needed, but they cannot always be generated, because
11919 -- of order of elaboration issues.
11921 elsif Is_Record_Type (T)
11922 and then Ekind (Formal) = E_In_Parameter
11923 and then Chars (Formal) /= Name_uInit
11924 and then not Is_Unchecked_Union (T)
11925 and then not Is_Discrim_SO_Function (Subp)
11929 -- All other cases do not need an actual subtype
11932 AS_Needed := False;
11935 -- Generate actual subtypes for unconstrained arrays and
11936 -- unconstrained discriminated records.
11939 if Nkind (N) = N_Accept_Statement then
11941 -- If expansion is active, the formal is replaced by a local
11942 -- variable that renames the corresponding entry of the
11943 -- parameter block, and it is this local variable that may
11944 -- require an actual subtype.
11946 if Expander_Active then
11947 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11949 Decl := Build_Actual_Subtype (T, Formal);
11952 if Present (Handled_Statement_Sequence (N)) then
11954 First (Statements (Handled_Statement_Sequence (N)));
11955 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11956 Mark_Rewrite_Insertion (Decl);
11958 -- If the accept statement has no body, there will be no
11959 -- reference to the actuals, so no need to compute actual
11966 Decl := Build_Actual_Subtype (T, Formal);
11967 Prepend (Decl, Declarations (N));
11968 Mark_Rewrite_Insertion (Decl);
11971 -- The declaration uses the bounds of an existing object, and
11972 -- therefore needs no constraint checks.
11974 Analyze (Decl, Suppress => All_Checks);
11975 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11977 -- We need to freeze manually the generated type when it is
11978 -- inserted anywhere else than in a declarative part.
11980 if Present (First_Stmt) then
11981 Insert_List_Before_And_Analyze (First_Stmt,
11982 Freeze_Entity (Defining_Identifier (Decl), N));
11984 -- Ditto if the type has a dynamic predicate, because the
11985 -- generated function will mention the actual subtype. The
11986 -- predicate may come from an explicit aspect of be inherited.
11988 elsif Has_Predicates (T) then
11989 Insert_List_Before_And_Analyze (Decl,
11990 Freeze_Entity (Defining_Identifier (Decl), N));
11993 if Nkind (N) = N_Accept_Statement
11994 and then Expander_Active
11996 Set_Actual_Subtype (Renamed_Object (Formal),
11997 Defining_Identifier (Decl));
11999 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
12003 Next_Formal (Formal);
12005 end Set_Actual_Subtypes;
12007 ---------------------
12008 -- Set_Formal_Mode --
12009 ---------------------
12011 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
12012 Spec : constant Node_Id := Parent (Formal_Id);
12013 Id : constant Entity_Id := Scope (Formal_Id);
12016 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
12017 -- since we ensure that corresponding actuals are always valid at the
12018 -- point of the call.
12020 if Out_Present (Spec) then
12021 if Ekind_In (Id, E_Entry, E_Entry_Family)
12022 or else Is_Subprogram_Or_Generic_Subprogram (Id)
12024 Set_Has_Out_Or_In_Out_Parameter (Id, True);
12027 if Ekind_In (Id, E_Function, E_Generic_Function) then
12029 -- [IN] OUT parameters allowed for functions in Ada 2012
12031 if Ada_Version >= Ada_2012 then
12033 -- Even in Ada 2012 operators can only have IN parameters
12035 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
12036 Error_Msg_N ("operators can only have IN parameters", Spec);
12039 if In_Present (Spec) then
12040 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12042 Set_Ekind (Formal_Id, E_Out_Parameter);
12045 -- But not in earlier versions of Ada
12048 Error_Msg_N ("functions can only have IN parameters", Spec);
12049 Set_Ekind (Formal_Id, E_In_Parameter);
12052 elsif In_Present (Spec) then
12053 Set_Ekind (Formal_Id, E_In_Out_Parameter);
12056 Set_Ekind (Formal_Id, E_Out_Parameter);
12057 Set_Never_Set_In_Source (Formal_Id, True);
12058 Set_Is_True_Constant (Formal_Id, False);
12059 Set_Current_Value (Formal_Id, Empty);
12063 Set_Ekind (Formal_Id, E_In_Parameter);
12066 -- Set Is_Known_Non_Null for access parameters since the language
12067 -- guarantees that access parameters are always non-null. We also set
12068 -- Can_Never_Be_Null, since there is no way to change the value.
12070 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
12072 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
12073 -- null; In Ada 2005, only if then null_exclusion is explicit.
12075 if Ada_Version < Ada_2005
12076 or else Can_Never_Be_Null (Etype (Formal_Id))
12078 Set_Is_Known_Non_Null (Formal_Id);
12079 Set_Can_Never_Be_Null (Formal_Id);
12082 -- Ada 2005 (AI-231): Null-exclusion access subtype
12084 elsif Is_Access_Type (Etype (Formal_Id))
12085 and then Can_Never_Be_Null (Etype (Formal_Id))
12087 Set_Is_Known_Non_Null (Formal_Id);
12089 -- We can also set Can_Never_Be_Null (thus preventing some junk
12090 -- access checks) for the case of an IN parameter, which cannot
12091 -- be changed, or for an IN OUT parameter, which can be changed but
12092 -- not to a null value. But for an OUT parameter, the initial value
12093 -- passed in can be null, so we can't set this flag in that case.
12095 if Ekind (Formal_Id) /= E_Out_Parameter then
12096 Set_Can_Never_Be_Null (Formal_Id);
12100 Set_Mechanism (Formal_Id, Default_Mechanism);
12101 Set_Formal_Validity (Formal_Id);
12102 end Set_Formal_Mode;
12104 -------------------------
12105 -- Set_Formal_Validity --
12106 -------------------------
12108 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12110 -- If no validity checking, then we cannot assume anything about the
12111 -- validity of parameters, since we do not know there is any checking
12112 -- of the validity on the call side.
12114 if not Validity_Checks_On then
12117 -- If validity checking for parameters is enabled, this means we are
12118 -- not supposed to make any assumptions about argument values.
12120 elsif Validity_Check_Parameters then
12123 -- If we are checking in parameters, we will assume that the caller is
12124 -- also checking parameters, so we can assume the parameter is valid.
12126 elsif Ekind (Formal_Id) = E_In_Parameter
12127 and then Validity_Check_In_Params
12129 Set_Is_Known_Valid (Formal_Id, True);
12131 -- Similar treatment for IN OUT parameters
12133 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12134 and then Validity_Check_In_Out_Params
12136 Set_Is_Known_Valid (Formal_Id, True);
12138 end Set_Formal_Validity;
12140 ------------------------
12141 -- Subtype_Conformant --
12142 ------------------------
12144 function Subtype_Conformant
12145 (New_Id : Entity_Id;
12146 Old_Id : Entity_Id;
12147 Skip_Controlling_Formals : Boolean := False) return Boolean
12151 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12152 Skip_Controlling_Formals => Skip_Controlling_Formals);
12154 end Subtype_Conformant;
12156 ---------------------
12157 -- Type_Conformant --
12158 ---------------------
12160 function Type_Conformant
12161 (New_Id : Entity_Id;
12162 Old_Id : Entity_Id;
12163 Skip_Controlling_Formals : Boolean := False) return Boolean
12167 May_Hide_Profile := False;
12169 (New_Id, Old_Id, Type_Conformant, False, Result,
12170 Skip_Controlling_Formals => Skip_Controlling_Formals);
12172 end Type_Conformant;
12174 -------------------------------
12175 -- Valid_Operator_Definition --
12176 -------------------------------
12178 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12181 Id : constant Name_Id := Chars (Designator);
12185 F := First_Formal (Designator);
12186 while Present (F) loop
12189 if Present (Default_Value (F)) then
12191 ("default values not allowed for operator parameters",
12194 -- For function instantiations that are operators, we must check
12195 -- separately that the corresponding generic only has in-parameters.
12196 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12197 -- an error could not arise in earlier versions of the language.
12199 elsif Ekind (F) /= E_In_Parameter then
12200 Error_Msg_N ("operators can only have IN parameters", F);
12206 -- Verify that user-defined operators have proper number of arguments
12207 -- First case of operators which can only be unary
12209 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12212 -- Case of operators which can be unary or binary
12214 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12215 N_OK := (N in 1 .. 2);
12217 -- All other operators can only be binary
12225 ("incorrect number of arguments for operator", Designator);
12229 and then Base_Type (Etype (Designator)) = Standard_Boolean
12230 and then not Is_Intrinsic_Subprogram (Designator)
12233 ("explicit definition of inequality not allowed", Designator);
12235 end Valid_Operator_Definition;