1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Inline; use Inline;
44 with Itypes; use Itypes;
45 with Lib.Xref; use Lib.Xref;
46 with Layout; use Layout;
47 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Output; use Output;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch4; use Sem_Ch4;
61 with Sem_Ch5; use Sem_Ch5;
62 with Sem_Ch8; use Sem_Ch8;
63 with Sem_Ch9; use Sem_Ch9;
64 with Sem_Ch10; use Sem_Ch10;
65 with Sem_Ch12; use Sem_Ch12;
66 with Sem_Ch13; use Sem_Ch13;
67 with Sem_Dim; use Sem_Dim;
68 with Sem_Disp; use Sem_Disp;
69 with Sem_Dist; use Sem_Dist;
70 with Sem_Elim; use Sem_Elim;
71 with Sem_Eval; use Sem_Eval;
72 with Sem_Mech; use Sem_Mech;
73 with Sem_Prag; use Sem_Prag;
74 with Sem_Res; use Sem_Res;
75 with Sem_Util; use Sem_Util;
76 with Sem_Type; use Sem_Type;
77 with Sem_Warn; use Sem_Warn;
78 with Sinput; use Sinput;
79 with Stand; use Stand;
80 with Sinfo; use Sinfo;
81 with Sinfo.CN; use Sinfo.CN;
82 with Snames; use Snames;
83 with Stringt; use Stringt;
85 with Stylesw; use Stylesw;
86 with Tbuild; use Tbuild;
87 with Uintp; use Uintp;
88 with Urealp; use Urealp;
89 with Validsw; use Validsw;
91 package body Sem_Ch6 is
93 May_Hide_Profile : Boolean := False;
94 -- This flag is used to indicate that two formals in two subprograms being
95 -- checked for conformance differ only in that one is an access parameter
96 -- while the other is of a general access type with the same designated
97 -- type. In this case, if the rest of the signatures match, a call to
98 -- either subprogram may be ambiguous, which is worth a warning. The flag
99 -- is set in Compatible_Types, and the warning emitted in
100 -- New_Overloaded_Entity.
102 -----------------------
103 -- Local Subprograms --
104 -----------------------
106 procedure Analyze_Function_Return (N : Node_Id);
107 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
108 -- applies to a [generic] function.
110 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
111 -- Analyze a generic subprogram body. N is the body to be analyzed, and
112 -- Gen_Id is the defining entity Id for the corresponding spec.
114 procedure Analyze_Null_Procedure
116 Is_Completion : out Boolean);
117 -- A null procedure can be a declaration or (Ada 2012) a completion
119 procedure Analyze_Return_Statement (N : Node_Id);
120 -- Common processing for simple and extended return statements
122 procedure Analyze_Return_Type (N : Node_Id);
123 -- Subsidiary to Process_Formals: analyze subtype mark in function
124 -- specification in a context where the formals are visible and hide
127 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
128 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
129 -- that we can use RETURN but not skip the debug output at the end.
131 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
132 -- Returns true if Subp can override a predefined operator.
134 procedure Check_Conformance
137 Ctype : Conformance_Type;
139 Conforms : out Boolean;
140 Err_Loc : Node_Id := Empty;
141 Get_Inst : Boolean := False;
142 Skip_Controlling_Formals : Boolean := False);
143 -- Given two entities, this procedure checks that the profiles associated
144 -- with these entities meet the conformance criterion given by the third
145 -- parameter. If they conform, Conforms is set True and control returns
146 -- to the caller. If they do not conform, Conforms is set to False, and
147 -- in addition, if Errmsg is True on the call, proper messages are output
148 -- to complain about the conformance failure. If Err_Loc is non_Empty
149 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
150 -- error messages are placed on the appropriate part of the construct
151 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
152 -- against a formal access-to-subprogram type so Get_Instance_Of must
155 procedure Check_Limited_Return
159 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning limited
160 -- types. Used only for simple return statements. Expr is the expression
163 procedure Check_Subprogram_Order (N : Node_Id);
164 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
165 -- the alpha ordering rule for N if this ordering requirement applicable.
167 procedure Check_Returns
171 Proc : Entity_Id := Empty);
172 -- Called to check for missing return statements in a function body, or for
173 -- returns present in a procedure body which has No_Return set. HSS is the
174 -- handled statement sequence for the subprogram body. This procedure
175 -- checks all flow paths to make sure they either have return (Mode = 'F',
176 -- used for functions) or do not have a return (Mode = 'P', used for
177 -- No_Return procedures). The flag Err is set if there are any control
178 -- paths not explicitly terminated by a return in the function case, and is
179 -- True otherwise. Proc is the entity for the procedure case and is used
180 -- in posting the warning message.
182 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
183 -- In Ada 2012, a primitive equality operator on an untagged record type
184 -- must appear before the type is frozen, and have the same visibility as
185 -- that of the type. This procedure checks that this rule is met, and
186 -- otherwise emits an error on the subprogram declaration and a warning
187 -- on the earlier freeze point if it is easy to locate. In Ada 2012 mode,
188 -- this routine outputs errors (or warnings if -gnatd.E is set). In earlier
189 -- versions of Ada, warnings are output if Warn_On_Ada_2012_Incompatibility
190 -- is set, otherwise the call has no effect.
192 procedure Enter_Overloaded_Entity (S : Entity_Id);
193 -- This procedure makes S, a new overloaded entity, into the first visible
194 -- entity with that name.
196 function Is_Non_Overriding_Operation
198 New_E : Entity_Id) return Boolean;
199 -- Enforce the rule given in 12.3(18): a private operation in an instance
200 -- overrides an inherited operation only if the corresponding operation
201 -- was overriding in the generic. This needs to be checked for primitive
202 -- operations of types derived (in the generic unit) from formal private
203 -- or formal derived types.
205 procedure Make_Inequality_Operator (S : Entity_Id);
206 -- Create the declaration for an inequality operator that is implicitly
207 -- created by a user-defined equality operator that yields a boolean.
209 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
210 -- Formal_Id is an formal parameter entity. This procedure deals with
211 -- setting the proper validity status for this entity, which depends on
212 -- the kind of parameter and the validity checking mode.
214 ---------------------------------------------
215 -- Analyze_Abstract_Subprogram_Declaration --
216 ---------------------------------------------
218 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
219 Scop : constant Entity_Id := Current_Scope;
220 Subp_Id : constant Entity_Id :=
221 Analyze_Subprogram_Specification (Specification (N));
224 Check_SPARK_05_Restriction ("abstract subprogram is not allowed", N);
226 Generate_Definition (Subp_Id);
228 -- Set the SPARK mode from the current context (may be overwritten later
229 -- with explicit pragma).
231 Set_SPARK_Pragma (Subp_Id, SPARK_Mode_Pragma);
232 Set_SPARK_Pragma_Inherited (Subp_Id);
234 -- Preserve relevant elaboration-related attributes of the context which
235 -- are no longer available or very expensive to recompute once analysis,
236 -- resolution, and expansion are over.
238 Mark_Elaboration_Attributes
242 Set_Is_Abstract_Subprogram (Subp_Id);
243 New_Overloaded_Entity (Subp_Id);
244 Check_Delayed_Subprogram (Subp_Id);
246 Set_Categorization_From_Scope (Subp_Id, Scop);
248 if Ekind (Scope (Subp_Id)) = E_Protected_Type then
249 Error_Msg_N ("abstract subprogram not allowed in protected type", N);
251 -- Issue a warning if the abstract subprogram is neither a dispatching
252 -- operation nor an operation that overrides an inherited subprogram or
253 -- predefined operator, since this most likely indicates a mistake.
255 elsif Warn_On_Redundant_Constructs
256 and then not Is_Dispatching_Operation (Subp_Id)
257 and then not Present (Overridden_Operation (Subp_Id))
258 and then (not Is_Operator_Symbol_Name (Chars (Subp_Id))
259 or else Scop /= Scope (Etype (First_Formal (Subp_Id))))
262 ("abstract subprogram is not dispatching or overriding?r?", N);
265 Generate_Reference_To_Formals (Subp_Id);
266 Check_Eliminated (Subp_Id);
268 if Has_Aspects (N) then
269 Analyze_Aspect_Specifications (N, Subp_Id);
271 end Analyze_Abstract_Subprogram_Declaration;
273 ---------------------------------
274 -- Analyze_Expression_Function --
275 ---------------------------------
277 procedure Analyze_Expression_Function (N : Node_Id) is
278 Expr : constant Node_Id := Expression (N);
279 Loc : constant Source_Ptr := Sloc (N);
280 LocX : constant Source_Ptr := Sloc (Expr);
281 Spec : constant Node_Id := Specification (N);
283 procedure Freeze_Expr_Types (Def_Id : Entity_Id);
284 -- N is an expression function that is a completion and Def_Id its
285 -- defining entity. Freeze before N all the types referenced by the
286 -- expression of the function.
288 -----------------------
289 -- Freeze_Expr_Types --
290 -----------------------
292 procedure Freeze_Expr_Types (Def_Id : Entity_Id) is
293 function Cloned_Expression return Node_Id;
294 -- Build a duplicate of the expression of the return statement that
295 -- has no defining entities shared with the original expression.
297 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result;
298 -- Freeze all types referenced in the subtree rooted at Node
300 -----------------------
301 -- Cloned_Expression --
302 -----------------------
304 function Cloned_Expression return Node_Id is
305 function Clone_Id (Node : Node_Id) return Traverse_Result;
306 -- Tree traversal routine that clones the defining identifier of
307 -- iterator and loop parameter specification nodes.
313 function Clone_Id (Node : Node_Id) return Traverse_Result is
315 if Nkind_In (Node, N_Iterator_Specification,
316 N_Loop_Parameter_Specification)
318 Set_Defining_Identifier (Node,
319 New_Copy (Defining_Identifier (Node)));
325 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id);
329 Dup_Expr : constant Node_Id := New_Copy_Tree (Expr);
331 -- Start of processing for Cloned_Expression
334 -- We must duplicate the expression with semantic information to
335 -- inherit the decoration of global entities in generic instances.
336 -- Set the parent of the new node to be the parent of the original
337 -- to get the proper context, which is needed for complete error
338 -- reporting and for semantic analysis.
340 Set_Parent (Dup_Expr, Parent (Expr));
342 -- Replace the defining identifier of iterators and loop param
343 -- specifications by a clone to ensure that the cloned expression
344 -- and the original expression don't have shared identifiers;
345 -- otherwise, as part of the preanalysis of the expression, these
346 -- shared identifiers may be left decorated with itypes which
347 -- will not be available in the tree passed to the backend.
349 Clone_Def_Ids (Dup_Expr);
352 end Cloned_Expression;
354 ----------------------
355 -- Freeze_Type_Refs --
356 ----------------------
358 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is
359 procedure Check_And_Freeze_Type (Typ : Entity_Id);
360 -- Check that Typ is fully declared and freeze it if so
362 ---------------------------
363 -- Check_And_Freeze_Type --
364 ---------------------------
366 procedure Check_And_Freeze_Type (Typ : Entity_Id) is
368 -- Skip Itypes created by the preanalysis, and itypes whose
369 -- scope is another type (i.e. component subtypes that depend
370 -- on a discriminant),
373 and then (Scope_Within_Or_Same (Scope (Typ), Def_Id)
374 or else Is_Type (Scope (Typ)))
379 -- This provides a better error message than generating
380 -- primitives whose compilation fails much later. Refine
381 -- the error message if possible.
383 Check_Fully_Declared (Typ, Node);
385 if Error_Posted (Node) then
386 if Has_Private_Component (Typ)
387 and then not Is_Private_Type (Typ)
389 Error_Msg_NE ("\type& has private component", Node, Typ);
393 Freeze_Before (N, Typ);
395 end Check_And_Freeze_Type;
397 -- Start of processing for Freeze_Type_Refs
400 -- Check that a type referenced by an entity can be frozen
402 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
403 Check_And_Freeze_Type (Etype (Entity (Node)));
405 -- Check that the enclosing record type can be frozen
407 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
408 Check_And_Freeze_Type (Scope (Entity (Node)));
411 -- Freezing an access type does not freeze the designated type,
412 -- but freezing conversions between access to interfaces requires
413 -- that the interface types themselves be frozen, so that dispatch
414 -- table entities are properly created.
416 -- Unclear whether a more general rule is needed ???
418 elsif Nkind (Node) = N_Type_Conversion
419 and then Is_Access_Type (Etype (Node))
420 and then Is_Interface (Designated_Type (Etype (Node)))
422 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
425 -- An implicit dereference freezes the designated type. In the
426 -- case of a dispatching call whose controlling argument is an
427 -- access type, the dereference is not made explicit, so we must
428 -- check for such a call and freeze the designated type.
430 if Nkind (Node) in N_Has_Etype
431 and then Present (Etype (Node))
432 and then Is_Access_Type (Etype (Node))
433 and then Nkind (Parent (Node)) = N_Function_Call
434 and then Node = Controlling_Argument (Parent (Node))
436 Check_And_Freeze_Type (Designated_Type (Etype (Node)));
439 -- No point in posting several errors on the same expression
441 if Serious_Errors_Detected > 0 then
446 end Freeze_Type_Refs;
448 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs);
452 Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id);
453 Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id);
454 Dup_Expr : constant Node_Id := Cloned_Expression;
456 -- Start of processing for Freeze_Expr_Types
459 -- Preanalyze a duplicate of the expression to have available the
460 -- minimum decoration needed to locate referenced unfrozen types
461 -- without adding any decoration to the function expression.
464 Install_Formals (Def_Id);
466 Preanalyze_Spec_Expression (Dup_Expr, Etype (Def_Id));
469 -- Restore certain attributes of Def_Id since the preanalysis may
470 -- have introduced itypes to this scope, thus modifying attributes
471 -- First_Entity and Last_Entity.
473 Set_First_Entity (Def_Id, Saved_First_Entity);
474 Set_Last_Entity (Def_Id, Saved_Last_Entity);
476 if Present (Last_Entity (Def_Id)) then
477 Set_Next_Entity (Last_Entity (Def_Id), Empty);
480 -- Freeze all types referenced in the expression
482 Freeze_References (Dup_Expr);
483 end Freeze_Expr_Types;
493 Def_Id : Entity_Id := Empty;
495 -- If the expression is a completion, Prev is the entity whose
496 -- declaration is completed. Def_Id is needed to analyze the spec.
498 -- Start of processing for Analyze_Expression_Function
501 -- This is one of the occasions on which we transform the tree during
502 -- semantic analysis. If this is a completion, transform the expression
503 -- function into an equivalent subprogram body, and analyze it.
505 -- Expression functions are inlined unconditionally. The back-end will
506 -- determine whether this is possible.
508 Inline_Processing_Required := True;
510 -- Create a specification for the generated body. This must be done
511 -- prior to the analysis of the initial declaration.
513 New_Spec := Copy_Subprogram_Spec (Spec);
514 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
516 -- If there are previous overloadable entities with the same name,
517 -- check whether any of them is completed by the expression function.
518 -- In a generic context a formal subprogram has no completion.
521 and then Is_Overloadable (Prev)
522 and then not Is_Formal_Subprogram (Prev)
524 Def_Id := Analyze_Subprogram_Specification (Spec);
525 Prev := Find_Corresponding_Spec (N);
527 -- The previous entity may be an expression function as well, in
528 -- which case the redeclaration is illegal.
531 and then Nkind (Original_Node (Unit_Declaration_Node (Prev))) =
532 N_Expression_Function
534 Error_Msg_Sloc := Sloc (Prev);
535 Error_Msg_N ("& conflicts with declaration#", Def_Id);
540 Ret := Make_Simple_Return_Statement (LocX, Expr);
543 Make_Subprogram_Body (Loc,
544 Specification => New_Spec,
545 Declarations => Empty_List,
546 Handled_Statement_Sequence =>
547 Make_Handled_Sequence_Of_Statements (LocX,
548 Statements => New_List (Ret)));
549 Set_Was_Expression_Function (New_Body);
551 -- If the expression completes a generic subprogram, we must create a
552 -- separate node for the body, because at instantiation the original
553 -- node of the generic copy must be a generic subprogram body, and
554 -- cannot be a expression function. Otherwise we just rewrite the
555 -- expression with the non-generic body.
557 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
558 Insert_After (N, New_Body);
560 -- Propagate any aspects or pragmas that apply to the expression
561 -- function to the proper body when the expression function acts
564 if Has_Aspects (N) then
565 Move_Aspects (N, To => New_Body);
568 Relocate_Pragmas_To_Body (New_Body);
570 Rewrite (N, Make_Null_Statement (Loc));
571 Set_Has_Completion (Prev, False);
574 Set_Is_Inlined (Prev);
576 -- If the expression function is a completion, the previous declaration
577 -- must come from source. We know already that it appears in the current
578 -- scope. The entity itself may be internally created if within a body
582 and then Is_Overloadable (Prev)
583 and then not Is_Formal_Subprogram (Prev)
584 and then Comes_From_Source (Parent (Prev))
586 Set_Has_Completion (Prev, False);
587 Set_Is_Inlined (Prev);
589 -- AI12-0103: Expression functions that are a completion freeze their
590 -- expression but don't freeze anything else (unlike regular bodies).
592 -- Note that we cannot defer this freezing to the analysis of the
593 -- expression itself, because a freeze node might appear in a nested
594 -- scope, leading to an elaboration order issue in gigi.
595 -- As elsewhere, we do not emit freeze nodes within a generic unit.
597 if not Inside_A_Generic then
598 Freeze_Expr_Types (Def_Id);
601 -- For navigation purposes, indicate that the function is a body
603 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
604 Rewrite (N, New_Body);
606 -- Remove any existing aspects from the original node because the act
607 -- of rewriting causes the list to be shared between the two nodes.
609 Orig_N := Original_Node (N);
610 Remove_Aspects (Orig_N);
612 -- Propagate any pragmas that apply to expression function to the
613 -- proper body when the expression function acts as a completion.
614 -- Aspects are automatically transfered because of node rewriting.
616 Relocate_Pragmas_To_Body (N);
619 -- Once the aspects of the generated body have been analyzed, create
620 -- a copy for ASIS purposes and associate it with the original node.
622 if Has_Aspects (N) then
623 Set_Aspect_Specifications (Orig_N,
624 New_Copy_List_Tree (Aspect_Specifications (N)));
627 -- Prev is the previous entity with the same name, but it is can
628 -- be an unrelated spec that is not completed by the expression
629 -- function. In that case the relevant entity is the one in the body.
630 -- Not clear that the backend can inline it in this case ???
632 if Has_Completion (Prev) then
634 -- The formals of the expression function are body formals,
635 -- and do not appear in the ali file, which will only contain
636 -- references to the formals of the original subprogram spec.
643 F1 := First_Formal (Def_Id);
644 F2 := First_Formal (Prev);
646 while Present (F1) loop
647 Set_Spec_Entity (F1, F2);
654 Set_Is_Inlined (Defining_Entity (New_Body));
657 -- If this is not a completion, create both a declaration and a body, so
658 -- that the expression can be inlined whenever possible.
661 -- An expression function that is not a completion is not a
662 -- subprogram declaration, and thus cannot appear in a protected
665 if Nkind (Parent (N)) = N_Protected_Definition then
667 ("an expression function is not a legal protected operation", N);
670 Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Spec));
672 -- Remove any existing aspects from the original node because the act
673 -- of rewriting causes the list to be shared between the two nodes.
675 Orig_N := Original_Node (N);
676 Remove_Aspects (Orig_N);
680 -- Once the aspects of the generated spec have been analyzed, create
681 -- a copy for ASIS purposes and associate it with the original node.
683 if Has_Aspects (N) then
684 Set_Aspect_Specifications (Orig_N,
685 New_Copy_List_Tree (Aspect_Specifications (N)));
688 -- If aspect SPARK_Mode was specified on the body, it needs to be
689 -- repeated both on the generated spec and the body.
691 Asp := Find_Aspect (Defining_Unit_Name (Spec), Aspect_SPARK_Mode);
693 if Present (Asp) then
694 Asp := New_Copy_Tree (Asp);
695 Set_Analyzed (Asp, False);
696 Set_Aspect_Specifications (New_Body, New_List (Asp));
699 Def_Id := Defining_Entity (N);
700 Set_Is_Inlined (Def_Id);
702 -- Establish the linkages between the spec and the body. These are
703 -- used when the expression function acts as the prefix of attribute
704 -- 'Access in order to freeze the original expression which has been
705 -- moved to the generated body.
707 Set_Corresponding_Body (N, Defining_Entity (New_Body));
708 Set_Corresponding_Spec (New_Body, Def_Id);
710 -- Within a generic pre-analyze the original expression for name
711 -- capture. The body is also generated but plays no role in
712 -- this because it is not part of the original source.
714 if Inside_A_Generic then
715 Set_Has_Completion (Def_Id);
717 Install_Formals (Def_Id);
718 Preanalyze_Spec_Expression (Expr, Etype (Def_Id));
722 -- To prevent premature freeze action, insert the new body at the end
723 -- of the current declarations, or at the end of the package spec.
724 -- However, resolve usage names now, to prevent spurious visibility
725 -- on later entities. Note that the function can now be called in
726 -- the current declarative part, which will appear to be prior to
727 -- the presence of the body in the code. There are nevertheless no
728 -- order of elaboration issues because all name resolution has taken
729 -- place at the point of declaration.
732 Decls : List_Id := List_Containing (N);
733 Expr : constant Node_Id := Expression (Ret);
734 Par : constant Node_Id := Parent (Decls);
735 Typ : constant Entity_Id := Etype (Def_Id);
738 -- If this is a wrapper created for in an instance for a formal
739 -- subprogram, insert body after declaration, to be analyzed when
740 -- the enclosing instance is analyzed.
743 and then Is_Generic_Actual_Subprogram (Def_Id)
745 Insert_After (N, New_Body);
748 if Nkind (Par) = N_Package_Specification
749 and then Decls = Visible_Declarations (Par)
750 and then Present (Private_Declarations (Par))
751 and then not Is_Empty_List (Private_Declarations (Par))
753 Decls := Private_Declarations (Par);
756 Insert_After (Last (Decls), New_Body);
758 -- Preanalyze the expression if not already done above
760 if not Inside_A_Generic then
762 Install_Formals (Def_Id);
763 Preanalyze_Spec_Expression (Expr, Typ);
764 Check_Limited_Return (Original_Node (N), Expr, Typ);
771 -- Check incorrect use of dynamically tagged expression. This doesn't
772 -- fall out automatically when analyzing the generated function body,
773 -- because Check_Dynamically_Tagged_Expression deliberately ignores
774 -- nodes that don't come from source.
777 and then Nkind (Def_Id) in N_Has_Etype
778 and then Is_Tagged_Type (Etype (Def_Id))
780 Check_Dynamically_Tagged_Expression
782 Typ => Etype (Def_Id),
783 Related_Nod => Original_Node (N));
786 -- If the return expression is a static constant, we suppress warning
787 -- messages on unused formals, which in most cases will be noise.
789 Set_Is_Trivial_Subprogram
790 (Defining_Entity (New_Body), Is_OK_Static_Expression (Expr));
791 end Analyze_Expression_Function;
793 ----------------------------------------
794 -- Analyze_Extended_Return_Statement --
795 ----------------------------------------
797 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
799 Check_Compiler_Unit ("extended return statement", N);
800 Analyze_Return_Statement (N);
801 end Analyze_Extended_Return_Statement;
803 ----------------------------
804 -- Analyze_Function_Call --
805 ----------------------------
807 procedure Analyze_Function_Call (N : Node_Id) is
808 Actuals : constant List_Id := Parameter_Associations (N);
809 Func_Nam : constant Node_Id := Name (N);
815 -- A call of the form A.B (X) may be an Ada 2005 call, which is
816 -- rewritten as B (A, X). If the rewriting is successful, the call
817 -- has been analyzed and we just return.
819 if Nkind (Func_Nam) = N_Selected_Component
820 and then Name (N) /= Func_Nam
821 and then Is_Rewrite_Substitution (N)
822 and then Present (Etype (N))
827 -- If error analyzing name, then set Any_Type as result type and return
829 if Etype (Func_Nam) = Any_Type then
830 Set_Etype (N, Any_Type);
834 -- Otherwise analyze the parameters
836 if Present (Actuals) then
837 Actual := First (Actuals);
838 while Present (Actual) loop
840 Check_Parameterless_Call (Actual);
846 end Analyze_Function_Call;
848 -----------------------------
849 -- Analyze_Function_Return --
850 -----------------------------
852 procedure Analyze_Function_Return (N : Node_Id) is
853 Loc : constant Source_Ptr := Sloc (N);
854 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
855 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
857 R_Type : constant Entity_Id := Etype (Scope_Id);
858 -- Function result subtype
860 procedure Check_Aggregate_Accessibility (Aggr : Node_Id);
861 -- Apply legality rule of 6.5 (5.8) to the access discriminants of an
862 -- aggregate in a return statement.
864 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
865 -- Check that the return_subtype_indication properly matches the result
866 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
868 -----------------------------------
869 -- Check_Aggregate_Accessibility --
870 -----------------------------------
872 procedure Check_Aggregate_Accessibility (Aggr : Node_Id) is
873 Typ : constant Entity_Id := Etype (Aggr);
880 if Is_Record_Type (Typ) and then Has_Discriminants (Typ) then
881 Discr := First_Discriminant (Typ);
882 Assoc := First (Component_Associations (Aggr));
883 while Present (Discr) loop
884 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
885 Expr := Expression (Assoc);
887 if Nkind (Expr) = N_Attribute_Reference
888 and then Attribute_Name (Expr) /= Name_Unrestricted_Access
890 Obj := Prefix (Expr);
891 while Nkind_In (Obj, N_Indexed_Component,
892 N_Selected_Component)
897 -- Do not check aliased formals or function calls. A
898 -- run-time check may still be needed ???
900 if Is_Entity_Name (Obj)
901 and then Comes_From_Source (Obj)
903 if Is_Formal (Entity (Obj))
904 and then Is_Aliased (Entity (Obj))
908 elsif Object_Access_Level (Obj) >
909 Scope_Depth (Scope (Scope_Id))
912 ("access discriminant in return aggregate would "
913 & "be a dangling reference", Obj);
919 Next_Discriminant (Discr);
922 end Check_Aggregate_Accessibility;
924 -------------------------------------
925 -- Check_Return_Subtype_Indication --
926 -------------------------------------
928 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
929 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
931 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
932 -- Subtype given in the extended return statement (must match R_Type)
934 Subtype_Ind : constant Node_Id :=
935 Object_Definition (Original_Node (Obj_Decl));
937 procedure Error_No_Match (N : Node_Id);
938 -- Output error messages for case where types do not statically
939 -- match. N is the location for the messages.
945 procedure Error_No_Match (N : Node_Id) is
948 ("subtype must statically match function result subtype", N);
950 if not Predicates_Match (R_Stm_Type, R_Type) then
951 Error_Msg_Node_2 := R_Type;
953 ("\predicate of& does not match predicate of&",
958 -- Start of processing for Check_Return_Subtype_Indication
961 -- First, avoid cascaded errors
963 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
967 -- "return access T" case; check that the return statement also has
968 -- "access T", and that the subtypes statically match:
969 -- if this is an access to subprogram the signatures must match.
971 if Is_Anonymous_Access_Type (R_Type) then
972 if Is_Anonymous_Access_Type (R_Stm_Type) then
973 if Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
975 if Base_Type (Designated_Type (R_Stm_Type)) /=
976 Base_Type (Designated_Type (R_Type))
977 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
979 Error_No_Match (Subtype_Mark (Subtype_Ind));
983 -- For two anonymous access to subprogram types, the types
984 -- themselves must be type conformant.
986 if not Conforming_Types
987 (R_Stm_Type, R_Type, Fully_Conformant)
989 Error_No_Match (Subtype_Ind);
994 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
997 -- If the return object is of an anonymous access type, then report
998 -- an error if the function's result type is not also anonymous.
1000 elsif Is_Anonymous_Access_Type (R_Stm_Type) then
1001 pragma Assert (not Is_Anonymous_Access_Type (R_Type));
1003 ("anonymous access not allowed for function with named access "
1004 & "result", Subtype_Ind);
1006 -- Subtype indication case: check that the return object's type is
1007 -- covered by the result type, and that the subtypes statically match
1008 -- when the result subtype is constrained. Also handle record types
1009 -- with unknown discriminants for which we have built the underlying
1010 -- record view. Coverage is needed to allow specific-type return
1011 -- objects when the result type is class-wide (see AI05-32).
1013 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
1014 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
1017 (Base_Type (R_Type),
1018 Underlying_Record_View (Base_Type (R_Stm_Type))))
1020 -- A null exclusion may be present on the return type, on the
1021 -- function specification, on the object declaration or on the
1024 if Is_Access_Type (R_Type)
1026 (Can_Never_Be_Null (R_Type)
1027 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
1028 Can_Never_Be_Null (R_Stm_Type)
1030 Error_No_Match (Subtype_Ind);
1033 -- AI05-103: for elementary types, subtypes must statically match
1035 if Is_Constrained (R_Type) or else Is_Access_Type (R_Type) then
1036 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
1037 Error_No_Match (Subtype_Ind);
1041 -- All remaining cases are illegal
1043 -- Note: previous versions of this subprogram allowed the return
1044 -- value to be the ancestor of the return type if the return type
1045 -- was a null extension. This was plainly incorrect.
1049 ("wrong type for return_subtype_indication", Subtype_Ind);
1051 end Check_Return_Subtype_Indication;
1053 ---------------------
1054 -- Local Variables --
1055 ---------------------
1058 Obj_Decl : Node_Id := Empty;
1060 -- Start of processing for Analyze_Function_Return
1063 Set_Return_Present (Scope_Id);
1065 if Nkind (N) = N_Simple_Return_Statement then
1066 Expr := Expression (N);
1068 -- Guard against a malformed expression. The parser may have tried to
1069 -- recover but the node is not analyzable.
1071 if Nkind (Expr) = N_Error then
1072 Set_Etype (Expr, Any_Type);
1073 Expander_Mode_Save_And_Set (False);
1077 -- The resolution of a controlled [extension] aggregate associated
1078 -- with a return statement creates a temporary which needs to be
1079 -- finalized on function exit. Wrap the return statement inside a
1080 -- block so that the finalization machinery can detect this case.
1081 -- This early expansion is done only when the return statement is
1082 -- not part of a handled sequence of statements.
1084 if Nkind_In (Expr, N_Aggregate,
1085 N_Extension_Aggregate)
1086 and then Needs_Finalization (R_Type)
1087 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1090 Make_Block_Statement (Loc,
1091 Handled_Statement_Sequence =>
1092 Make_Handled_Sequence_Of_Statements (Loc,
1093 Statements => New_List (Relocate_Node (N)))));
1101 -- Ada 2005 (AI-251): If the type of the returned object is
1102 -- an access to an interface type then we add an implicit type
1103 -- conversion to force the displacement of the "this" pointer to
1104 -- reference the secondary dispatch table. We cannot delay the
1105 -- generation of this implicit conversion until the expansion
1106 -- because in this case the type resolution changes the decoration
1107 -- of the expression node to match R_Type; by contrast, if the
1108 -- returned object is a class-wide interface type then it is too
1109 -- early to generate here the implicit conversion since the return
1110 -- statement may be rewritten by the expander into an extended
1111 -- return statement whose expansion takes care of adding the
1112 -- implicit type conversion to displace the pointer to the object.
1115 and then Serious_Errors_Detected = 0
1116 and then Is_Access_Type (R_Type)
1117 and then not Nkind_In (Expr, N_Null, N_Raise_Expression)
1118 and then Is_Interface (Designated_Type (R_Type))
1119 and then Is_Progenitor (Designated_Type (R_Type),
1120 Designated_Type (Etype (Expr)))
1122 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1126 Resolve (Expr, R_Type);
1127 Check_Limited_Return (N, Expr, R_Type);
1129 if Present (Expr) and then Nkind (Expr) = N_Aggregate then
1130 Check_Aggregate_Accessibility (Expr);
1134 -- RETURN only allowed in SPARK as the last statement in function
1136 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
1138 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
1139 or else Present (Next (N)))
1141 Check_SPARK_05_Restriction
1142 ("RETURN should be the last statement in function", N);
1146 Check_SPARK_05_Restriction ("extended RETURN is not allowed", N);
1147 Obj_Decl := Last (Return_Object_Declarations (N));
1149 -- Analyze parts specific to extended_return_statement:
1152 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
1153 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1156 Expr := Expression (Obj_Decl);
1158 -- Note: The check for OK_For_Limited_Init will happen in
1159 -- Analyze_Object_Declaration; we treat it as a normal
1160 -- object declaration.
1162 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
1165 Check_Return_Subtype_Indication (Obj_Decl);
1167 if Present (HSS) then
1170 if Present (Exception_Handlers (HSS)) then
1172 -- ???Has_Nested_Block_With_Handler needs to be set.
1173 -- Probably by creating an actual N_Block_Statement.
1174 -- Probably in Expand.
1180 -- Mark the return object as referenced, since the return is an
1181 -- implicit reference of the object.
1183 Set_Referenced (Defining_Identifier (Obj_Decl));
1185 Check_References (Stm_Entity);
1187 -- Check RM 6.5 (5.9/3)
1190 if Ada_Version < Ada_2012 then
1192 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
1193 -- Can it really happen (extended return???)
1196 ("aliased only allowed for limited return objects "
1197 & "in Ada 2012??", N);
1199 elsif not Is_Limited_View (R_Type) then
1201 ("aliased only allowed for limited return objects", N);
1207 -- Case of Expr present
1209 if Present (Expr) then
1211 -- Defend against previous errors
1213 if Nkind (Expr) = N_Empty
1214 or else No (Etype (Expr))
1219 -- Apply constraint check. Note that this is done before the implicit
1220 -- conversion of the expression done for anonymous access types to
1221 -- ensure correct generation of the null-excluding check associated
1222 -- with null-excluding expressions found in return statements.
1224 Apply_Constraint_Check (Expr, R_Type);
1226 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
1227 -- type, apply an implicit conversion of the expression to that type
1228 -- to force appropriate static and run-time accessibility checks.
1230 if Ada_Version >= Ada_2005
1231 and then Ekind (R_Type) = E_Anonymous_Access_Type
1233 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
1234 Analyze_And_Resolve (Expr, R_Type);
1236 -- If this is a local anonymous access to subprogram, the
1237 -- accessibility check can be applied statically. The return is
1238 -- illegal if the access type of the return expression is declared
1239 -- inside of the subprogram (except if it is the subtype indication
1240 -- of an extended return statement).
1242 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
1243 if not Comes_From_Source (Current_Scope)
1244 or else Ekind (Current_Scope) = E_Return_Statement
1249 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
1251 Error_Msg_N ("cannot return local access to subprogram", N);
1254 -- The expression cannot be of a formal incomplete type
1256 elsif Ekind (Etype (Expr)) = E_Incomplete_Type
1257 and then Is_Generic_Type (Etype (Expr))
1260 ("cannot return expression of a formal incomplete type", N);
1263 -- If the result type is class-wide, then check that the return
1264 -- expression's type is not declared at a deeper level than the
1265 -- function (RM05-6.5(5.6/2)).
1267 if Ada_Version >= Ada_2005
1268 and then Is_Class_Wide_Type (R_Type)
1270 if Type_Access_Level (Etype (Expr)) >
1271 Subprogram_Access_Level (Scope_Id)
1274 ("level of return expression type is deeper than "
1275 & "class-wide function!", Expr);
1279 -- Check incorrect use of dynamically tagged expression
1281 if Is_Tagged_Type (R_Type) then
1282 Check_Dynamically_Tagged_Expression
1288 -- ??? A real run-time accessibility check is needed in cases
1289 -- involving dereferences of access parameters. For now we just
1290 -- check the static cases.
1292 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
1293 and then Is_Limited_View (Etype (Scope_Id))
1294 and then Object_Access_Level (Expr) >
1295 Subprogram_Access_Level (Scope_Id)
1297 -- Suppress the message in a generic, where the rewriting
1300 if Inside_A_Generic then
1305 Make_Raise_Program_Error (Loc,
1306 Reason => PE_Accessibility_Check_Failed));
1309 Error_Msg_Warn := SPARK_Mode /= On;
1310 Error_Msg_N ("cannot return a local value by reference<<", N);
1311 Error_Msg_NE ("\& [<<", N, Standard_Program_Error);
1315 if Known_Null (Expr)
1316 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
1317 and then Null_Exclusion_Present (Parent (Scope_Id))
1319 Apply_Compile_Time_Constraint_Error
1321 Msg => "(Ada 2005) null not allowed for "
1322 & "null-excluding return??",
1323 Reason => CE_Null_Not_Allowed);
1326 -- RM 6.5 (5.4/3): accessibility checks also apply if the return object
1327 -- has no initializing expression.
1329 elsif Ada_Version > Ada_2005 and then Is_Class_Wide_Type (R_Type) then
1330 if Type_Access_Level (Etype (Defining_Identifier (Obj_Decl))) >
1331 Subprogram_Access_Level (Scope_Id)
1334 ("level of return expression type is deeper than "
1335 & "class-wide function!", Obj_Decl);
1338 end Analyze_Function_Return;
1340 -------------------------------------
1341 -- Analyze_Generic_Subprogram_Body --
1342 -------------------------------------
1344 procedure Analyze_Generic_Subprogram_Body
1348 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1349 Kind : constant Entity_Kind := Ekind (Gen_Id);
1350 Body_Id : Entity_Id;
1355 -- Copy body and disable expansion while analyzing the generic For a
1356 -- stub, do not copy the stub (which would load the proper body), this
1357 -- will be done when the proper body is analyzed.
1359 if Nkind (N) /= N_Subprogram_Body_Stub then
1360 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1363 -- Once the contents of the generic copy and the template are
1364 -- swapped, do the same for their respective aspect specifications.
1366 Exchange_Aspects (N, New_N);
1368 -- Collect all contract-related source pragmas found within the
1369 -- template and attach them to the contract of the subprogram body.
1370 -- This contract is used in the capture of global references within
1373 Create_Generic_Contract (N);
1378 Spec := Specification (N);
1380 -- Within the body of the generic, the subprogram is callable, and
1381 -- behaves like the corresponding non-generic unit.
1383 Body_Id := Defining_Entity (Spec);
1385 if Kind = E_Generic_Procedure
1386 and then Nkind (Spec) /= N_Procedure_Specification
1388 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1391 elsif Kind = E_Generic_Function
1392 and then Nkind (Spec) /= N_Function_Specification
1394 Error_Msg_N ("invalid body for generic function ", Body_Id);
1398 Set_Corresponding_Body (Gen_Decl, Body_Id);
1400 if Has_Completion (Gen_Id)
1401 and then Nkind (Parent (N)) /= N_Subunit
1403 Error_Msg_N ("duplicate generic body", N);
1406 Set_Has_Completion (Gen_Id);
1409 if Nkind (N) = N_Subprogram_Body_Stub then
1410 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1412 Set_Corresponding_Spec (N, Gen_Id);
1415 if Nkind (Parent (N)) = N_Compilation_Unit then
1416 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1419 -- Make generic parameters immediately visible in the body. They are
1420 -- needed to process the formals declarations. Then make the formals
1421 -- visible in a separate step.
1423 Push_Scope (Gen_Id);
1427 First_Ent : Entity_Id;
1430 First_Ent := First_Entity (Gen_Id);
1433 while Present (E) and then not Is_Formal (E) loop
1438 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1440 -- Now generic formals are visible, and the specification can be
1441 -- analyzed, for subsequent conformance check.
1443 Body_Id := Analyze_Subprogram_Specification (Spec);
1445 -- Make formal parameters visible
1449 -- E is the first formal parameter, we loop through the formals
1450 -- installing them so that they will be visible.
1452 Set_First_Entity (Gen_Id, E);
1453 while Present (E) loop
1459 -- Visible generic entity is callable within its own body
1461 Set_Ekind (Gen_Id, Ekind (Body_Id));
1462 Set_Ekind (Body_Id, E_Subprogram_Body);
1463 Set_Convention (Body_Id, Convention (Gen_Id));
1464 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1465 Set_Scope (Body_Id, Scope (Gen_Id));
1467 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1469 if Nkind (N) = N_Subprogram_Body_Stub then
1471 -- No body to analyze, so restore state of generic unit
1473 Set_Ekind (Gen_Id, Kind);
1474 Set_Ekind (Body_Id, Kind);
1476 if Present (First_Ent) then
1477 Set_First_Entity (Gen_Id, First_Ent);
1484 -- If this is a compilation unit, it must be made visible explicitly,
1485 -- because the compilation of the declaration, unlike other library
1486 -- unit declarations, does not. If it is not a unit, the following
1487 -- is redundant but harmless.
1489 Set_Is_Immediately_Visible (Gen_Id);
1490 Reference_Body_Formals (Gen_Id, Body_Id);
1492 if Is_Child_Unit (Gen_Id) then
1493 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1496 Set_Actual_Subtypes (N, Current_Scope);
1498 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
1499 Set_SPARK_Pragma_Inherited (Body_Id);
1501 -- Analyze any aspect specifications that appear on the generic
1504 if Has_Aspects (N) then
1505 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
1508 Analyze_Declarations (Declarations (N));
1511 -- Process the contract of the subprogram body after all declarations
1512 -- have been analyzed. This ensures that any contract-related pragmas
1513 -- are available through the N_Contract node of the body.
1515 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
1517 Analyze (Handled_Statement_Sequence (N));
1518 Save_Global_References (Original_Node (N));
1520 -- Prior to exiting the scope, include generic formals again (if any
1521 -- are present) in the set of local entities.
1523 if Present (First_Ent) then
1524 Set_First_Entity (Gen_Id, First_Ent);
1527 Check_References (Gen_Id);
1530 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1531 Update_Use_Clause_Chain;
1532 Validate_Categorization_Dependency (N, Gen_Id);
1534 Check_Subprogram_Order (N);
1536 -- Outside of its body, unit is generic again
1538 Set_Ekind (Gen_Id, Kind);
1539 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1542 Style.Check_Identifier (Body_Id, Gen_Id);
1546 end Analyze_Generic_Subprogram_Body;
1548 ----------------------------
1549 -- Analyze_Null_Procedure --
1550 ----------------------------
1552 procedure Analyze_Null_Procedure
1554 Is_Completion : out Boolean)
1556 Loc : constant Source_Ptr := Sloc (N);
1557 Spec : constant Node_Id := Specification (N);
1558 Designator : Entity_Id;
1560 Null_Body : Node_Id := Empty;
1561 Null_Stmt : Node_Id := Null_Statement (Spec);
1565 -- Capture the profile of the null procedure before analysis, for
1566 -- expansion at the freeze point and at each point of call. The body is
1567 -- used if the procedure has preconditions, or if it is a completion. In
1568 -- the first case the body is analyzed at the freeze point, in the other
1569 -- it replaces the null procedure declaration.
1571 -- For a null procedure that comes from source, a NULL statement is
1572 -- provided by the parser, which carries the source location of the
1573 -- NULL keyword, and has Comes_From_Source set. For a null procedure
1574 -- from expansion, create one now.
1576 if No (Null_Stmt) then
1577 Null_Stmt := Make_Null_Statement (Loc);
1581 Make_Subprogram_Body (Loc,
1582 Specification => New_Copy_Tree (Spec),
1583 Declarations => New_List,
1584 Handled_Statement_Sequence =>
1585 Make_Handled_Sequence_Of_Statements (Loc,
1586 Statements => New_List (Null_Stmt)));
1588 -- Create new entities for body and formals
1590 Set_Defining_Unit_Name (Specification (Null_Body),
1591 Make_Defining_Identifier
1592 (Sloc (Defining_Entity (N)),
1593 Chars (Defining_Entity (N))));
1595 Form := First (Parameter_Specifications (Specification (Null_Body)));
1596 while Present (Form) loop
1597 Set_Defining_Identifier (Form,
1598 Make_Defining_Identifier
1599 (Sloc (Defining_Identifier (Form)),
1600 Chars (Defining_Identifier (Form))));
1604 -- Determine whether the null procedure may be a completion of a generic
1605 -- suprogram, in which case we use the new null body as the completion
1606 -- and set minimal semantic information on the original declaration,
1607 -- which is rewritten as a null statement.
1609 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1611 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1612 Insert_Before (N, Null_Body);
1613 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1615 Rewrite (N, Make_Null_Statement (Loc));
1616 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1617 Is_Completion := True;
1621 -- Resolve the types of the formals now, because the freeze point may
1622 -- appear in a different context, e.g. an instantiation.
1624 Form := First (Parameter_Specifications (Specification (Null_Body)));
1625 while Present (Form) loop
1626 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1627 Find_Type (Parameter_Type (Form));
1629 elsif No (Access_To_Subprogram_Definition
1630 (Parameter_Type (Form)))
1632 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1634 -- The case of a null procedure with a formal that is an
1635 -- access-to-subprogram type, and that is used as an actual
1636 -- in an instantiation is left to the enthusiastic reader.
1646 -- If there are previous overloadable entities with the same name, check
1647 -- whether any of them is completed by the null procedure.
1649 if Present (Prev) and then Is_Overloadable (Prev) then
1650 Designator := Analyze_Subprogram_Specification (Spec);
1651 Prev := Find_Corresponding_Spec (N);
1654 if No (Prev) or else not Comes_From_Source (Prev) then
1655 Designator := Analyze_Subprogram_Specification (Spec);
1656 Set_Has_Completion (Designator);
1658 -- Signal to caller that this is a procedure declaration
1660 Is_Completion := False;
1662 -- Null procedures are always inlined, but generic formal subprograms
1663 -- which appear as such in the internal instance of formal packages,
1664 -- need no completion and are not marked Inline.
1667 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1669 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1670 Set_Body_To_Inline (N, Null_Body);
1671 Set_Is_Inlined (Designator);
1675 -- The null procedure is a completion. We unconditionally rewrite
1676 -- this as a null body (even if expansion is not active), because
1677 -- there are various error checks that are applied on this body
1678 -- when it is analyzed (e.g. correct aspect placement).
1680 if Has_Completion (Prev) then
1681 Error_Msg_Sloc := Sloc (Prev);
1682 Error_Msg_NE ("duplicate body for & declared#", N, Prev);
1685 Check_Previous_Null_Procedure (N, Prev);
1687 Is_Completion := True;
1688 Rewrite (N, Null_Body);
1691 end Analyze_Null_Procedure;
1693 -----------------------------
1694 -- Analyze_Operator_Symbol --
1695 -----------------------------
1697 -- An operator symbol such as "+" or "and" may appear in context where the
1698 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1699 -- is just a string, as in (conjunction = "or"). In these cases the parser
1700 -- generates this node, and the semantics does the disambiguation. Other
1701 -- such case are actuals in an instantiation, the generic unit in an
1702 -- instantiation, and pragma arguments.
1704 procedure Analyze_Operator_Symbol (N : Node_Id) is
1705 Par : constant Node_Id := Parent (N);
1708 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
1709 or else Nkind (Par) = N_Function_Instantiation
1710 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
1711 or else (Nkind (Par) = N_Pragma_Argument_Association
1712 and then not Is_Pragma_String_Literal (Par))
1713 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1714 or else (Nkind (Par) = N_Attribute_Reference
1715 and then Attribute_Name (Par) /= Name_Value)
1717 Find_Direct_Name (N);
1720 Change_Operator_Symbol_To_String_Literal (N);
1723 end Analyze_Operator_Symbol;
1725 -----------------------------------
1726 -- Analyze_Parameter_Association --
1727 -----------------------------------
1729 procedure Analyze_Parameter_Association (N : Node_Id) is
1731 Analyze (Explicit_Actual_Parameter (N));
1732 end Analyze_Parameter_Association;
1734 ----------------------------
1735 -- Analyze_Procedure_Call --
1736 ----------------------------
1738 -- WARNING: This routine manages Ghost regions. Return statements must be
1739 -- replaced by gotos which jump to the end of the routine and restore the
1742 procedure Analyze_Procedure_Call (N : Node_Id) is
1743 procedure Analyze_Call_And_Resolve;
1744 -- Do Analyze and Resolve calls for procedure call. At the end, check
1745 -- for illegal order dependence.
1746 -- ??? where is the check for illegal order dependencies?
1748 ------------------------------
1749 -- Analyze_Call_And_Resolve --
1750 ------------------------------
1752 procedure Analyze_Call_And_Resolve is
1754 if Nkind (N) = N_Procedure_Call_Statement then
1756 Resolve (N, Standard_Void_Type);
1760 end Analyze_Call_And_Resolve;
1764 Actuals : constant List_Id := Parameter_Associations (N);
1765 Loc : constant Source_Ptr := Sloc (N);
1766 P : constant Node_Id := Name (N);
1768 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
1769 -- Save the Ghost mode to restore on exit
1774 -- Start of processing for Analyze_Procedure_Call
1777 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1778 -- a procedure call or an entry call. The prefix may denote an access
1779 -- to subprogram type, in which case an implicit dereference applies.
1780 -- If the prefix is an indexed component (without implicit dereference)
1781 -- then the construct denotes a call to a member of an entire family.
1782 -- If the prefix is a simple name, it may still denote a call to a
1783 -- parameterless member of an entry family. Resolution of these various
1784 -- interpretations is delicate.
1786 -- Do not analyze machine code statements to avoid rejecting them in
1789 if CodePeer_Mode and then Nkind (P) = N_Qualified_Expression then
1790 Set_Etype (P, Standard_Void_Type);
1795 -- If this is a call of the form Obj.Op, the call may have been analyzed
1796 -- and possibly rewritten into a block, in which case we are done.
1798 if Analyzed (N) then
1801 -- If there is an error analyzing the name (which may have been
1802 -- rewritten if the original call was in prefix notation) then error
1803 -- has been emitted already, mark node and return.
1805 elsif Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1806 Set_Etype (N, Any_Type);
1810 -- A procedure call is Ghost when its name denotes a Ghost procedure.
1811 -- Set the mode now to ensure that any nodes generated during analysis
1812 -- and expansion are properly marked as Ghost.
1814 Mark_And_Set_Ghost_Procedure_Call (N);
1816 -- Otherwise analyze the parameters
1818 if Present (Actuals) then
1819 Actual := First (Actuals);
1821 while Present (Actual) loop
1823 Check_Parameterless_Call (Actual);
1828 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1830 if Nkind (P) = N_Attribute_Reference
1831 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1833 Name_Elab_Subp_Body)
1835 if Present (Actuals) then
1837 ("no parameters allowed for this call", First (Actuals));
1841 Set_Etype (N, Standard_Void_Type);
1844 elsif Is_Entity_Name (P)
1845 and then Is_Record_Type (Etype (Entity (P)))
1846 and then Remote_AST_I_Dereference (P)
1850 elsif Is_Entity_Name (P)
1851 and then Ekind (Entity (P)) /= E_Entry_Family
1853 if Is_Access_Type (Etype (P))
1854 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1855 and then No (Actuals)
1856 and then Comes_From_Source (N)
1858 Error_Msg_N ("missing explicit dereference in call", N);
1861 Analyze_Call_And_Resolve;
1863 -- If the prefix is the simple name of an entry family, this is a
1864 -- parameterless call from within the task body itself.
1866 elsif Is_Entity_Name (P)
1867 and then Nkind (P) = N_Identifier
1868 and then Ekind (Entity (P)) = E_Entry_Family
1869 and then Present (Actuals)
1870 and then No (Next (First (Actuals)))
1872 -- Can be call to parameterless entry family. What appears to be the
1873 -- sole argument is in fact the entry index. Rewrite prefix of node
1874 -- accordingly. Source representation is unchanged by this
1878 Make_Indexed_Component (Loc,
1880 Make_Selected_Component (Loc,
1881 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1882 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1883 Expressions => Actuals);
1884 Set_Name (N, New_N);
1885 Set_Etype (New_N, Standard_Void_Type);
1886 Set_Parameter_Associations (N, No_List);
1887 Analyze_Call_And_Resolve;
1889 elsif Nkind (P) = N_Explicit_Dereference then
1890 if Ekind (Etype (P)) = E_Subprogram_Type then
1891 Analyze_Call_And_Resolve;
1893 Error_Msg_N ("expect access to procedure in call", P);
1896 -- The name can be a selected component or an indexed component that
1897 -- yields an access to subprogram. Such a prefix is legal if the call
1898 -- has parameter associations.
1900 elsif Is_Access_Type (Etype (P))
1901 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1903 if Present (Actuals) then
1904 Analyze_Call_And_Resolve;
1906 Error_Msg_N ("missing explicit dereference in call ", N);
1909 -- If not an access to subprogram, then the prefix must resolve to the
1910 -- name of an entry, entry family, or protected operation.
1912 -- For the case of a simple entry call, P is a selected component where
1913 -- the prefix is the task and the selector name is the entry. A call to
1914 -- a protected procedure will have the same syntax. If the protected
1915 -- object contains overloaded operations, the entity may appear as a
1916 -- function, the context will select the operation whose type is Void.
1918 elsif Nkind (P) = N_Selected_Component
1919 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1923 -- When front-end inlining is enabled, as with SPARK_Mode, a call
1924 -- in prefix notation may still be missing its controlling argument,
1925 -- so perform the transformation now.
1927 if SPARK_Mode = On and then In_Inlined_Body then
1929 Subp : constant Entity_Id := Entity (Selector_Name (P));
1930 Typ : constant Entity_Id := Etype (Prefix (P));
1933 if Is_Tagged_Type (Typ)
1934 and then Present (First_Formal (Subp))
1935 and then (Etype (First_Formal (Subp)) = Typ
1937 Class_Wide_Type (Etype (First_Formal (Subp))) = Typ)
1938 and then Try_Object_Operation (P)
1943 Analyze_Call_And_Resolve;
1948 Analyze_Call_And_Resolve;
1951 elsif Nkind (P) = N_Selected_Component
1952 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1953 and then Present (Actuals)
1954 and then No (Next (First (Actuals)))
1956 -- Can be call to parameterless entry family. What appears to be the
1957 -- sole argument is in fact the entry index. Rewrite prefix of node
1958 -- accordingly. Source representation is unchanged by this
1962 Make_Indexed_Component (Loc,
1963 Prefix => New_Copy (P),
1964 Expressions => Actuals);
1965 Set_Name (N, New_N);
1966 Set_Etype (New_N, Standard_Void_Type);
1967 Set_Parameter_Associations (N, No_List);
1968 Analyze_Call_And_Resolve;
1970 -- For the case of a reference to an element of an entry family, P is
1971 -- an indexed component whose prefix is a selected component (task and
1972 -- entry family), and whose index is the entry family index.
1974 elsif Nkind (P) = N_Indexed_Component
1975 and then Nkind (Prefix (P)) = N_Selected_Component
1976 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1978 Analyze_Call_And_Resolve;
1980 -- If the prefix is the name of an entry family, it is a call from
1981 -- within the task body itself.
1983 elsif Nkind (P) = N_Indexed_Component
1984 and then Nkind (Prefix (P)) = N_Identifier
1985 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1988 Make_Selected_Component (Loc,
1990 New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1991 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1992 Rewrite (Prefix (P), New_N);
1994 Analyze_Call_And_Resolve;
1996 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1997 -- procedure name, so the construct can only be a qualified expression.
1999 elsif Nkind (P) = N_Qualified_Expression
2000 and then Ada_Version >= Ada_2012
2002 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
2005 -- Anything else is an error
2008 Error_Msg_N ("invalid procedure or entry call", N);
2012 Restore_Ghost_Mode (Saved_GM);
2013 end Analyze_Procedure_Call;
2015 ------------------------------
2016 -- Analyze_Return_Statement --
2017 ------------------------------
2019 procedure Analyze_Return_Statement (N : Node_Id) is
2020 pragma Assert (Nkind_In (N, N_Extended_Return_Statement,
2021 N_Simple_Return_Statement));
2023 Returns_Object : constant Boolean :=
2024 Nkind (N) = N_Extended_Return_Statement
2026 (Nkind (N) = N_Simple_Return_Statement
2027 and then Present (Expression (N)));
2028 -- True if we're returning something; that is, "return <expression>;"
2029 -- or "return Result : T [:= ...]". False for "return;". Used for error
2030 -- checking: If Returns_Object is True, N should apply to a function
2031 -- body; otherwise N should apply to a procedure body, entry body,
2032 -- accept statement, or extended return statement.
2034 function Find_What_It_Applies_To return Entity_Id;
2035 -- Find the entity representing the innermost enclosing body, accept
2036 -- statement, or extended return statement. If the result is a callable
2037 -- construct or extended return statement, then this will be the value
2038 -- of the Return_Applies_To attribute. Otherwise, the program is
2039 -- illegal. See RM-6.5(4/2).
2041 -----------------------------
2042 -- Find_What_It_Applies_To --
2043 -----------------------------
2045 function Find_What_It_Applies_To return Entity_Id is
2046 Result : Entity_Id := Empty;
2049 -- Loop outward through the Scope_Stack, skipping blocks, loops,
2050 -- and postconditions.
2052 for J in reverse 0 .. Scope_Stack.Last loop
2053 Result := Scope_Stack.Table (J).Entity;
2054 exit when not Ekind_In (Result, E_Block, E_Loop)
2055 and then Chars (Result) /= Name_uPostconditions;
2058 pragma Assert (Present (Result));
2060 end Find_What_It_Applies_To;
2062 -- Local declarations
2064 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
2065 Kind : constant Entity_Kind := Ekind (Scope_Id);
2066 Loc : constant Source_Ptr := Sloc (N);
2067 Stm_Entity : constant Entity_Id :=
2069 (E_Return_Statement, Current_Scope, Loc, 'R');
2071 -- Start of processing for Analyze_Return_Statement
2074 Set_Return_Statement_Entity (N, Stm_Entity);
2076 Set_Etype (Stm_Entity, Standard_Void_Type);
2077 Set_Return_Applies_To (Stm_Entity, Scope_Id);
2079 -- Place Return entity on scope stack, to simplify enforcement of 6.5
2080 -- (4/2): an inner return statement will apply to this extended return.
2082 if Nkind (N) = N_Extended_Return_Statement then
2083 Push_Scope (Stm_Entity);
2086 -- Check that pragma No_Return is obeyed. Don't complain about the
2087 -- implicitly-generated return that is placed at the end.
2089 if No_Return (Scope_Id) and then Comes_From_Source (N) then
2090 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
2093 -- Warn on any unassigned OUT parameters if in procedure
2095 if Ekind (Scope_Id) = E_Procedure then
2096 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
2099 -- Check that functions return objects, and other things do not
2101 if Kind = E_Function or else Kind = E_Generic_Function then
2102 if not Returns_Object then
2103 Error_Msg_N ("missing expression in return from function", N);
2106 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
2107 if Returns_Object then
2108 Error_Msg_N ("procedure cannot return value (use function)", N);
2111 elsif Kind = E_Entry or else Kind = E_Entry_Family then
2112 if Returns_Object then
2113 if Is_Protected_Type (Scope (Scope_Id)) then
2114 Error_Msg_N ("entry body cannot return value", N);
2116 Error_Msg_N ("accept statement cannot return value", N);
2120 elsif Kind = E_Return_Statement then
2122 -- We are nested within another return statement, which must be an
2123 -- extended_return_statement.
2125 if Returns_Object then
2126 if Nkind (N) = N_Extended_Return_Statement then
2128 ("extended return statement cannot be nested (use `RETURN;`)",
2131 -- Case of a simple return statement with a value inside extended
2132 -- return statement.
2136 ("return nested in extended return statement cannot return "
2137 & "value (use `RETURN;`)", N);
2142 Error_Msg_N ("illegal context for return statement", N);
2145 if Ekind_In (Kind, E_Function, E_Generic_Function) then
2146 Analyze_Function_Return (N);
2148 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
2149 Set_Return_Present (Scope_Id);
2152 if Nkind (N) = N_Extended_Return_Statement then
2156 Kill_Current_Values (Last_Assignment_Only => True);
2157 Check_Unreachable_Code (N);
2159 Analyze_Dimension (N);
2160 end Analyze_Return_Statement;
2162 -------------------------------------
2163 -- Analyze_Simple_Return_Statement --
2164 -------------------------------------
2166 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
2168 if Present (Expression (N)) then
2169 Mark_Coextensions (N, Expression (N));
2172 Analyze_Return_Statement (N);
2173 end Analyze_Simple_Return_Statement;
2175 -------------------------
2176 -- Analyze_Return_Type --
2177 -------------------------
2179 procedure Analyze_Return_Type (N : Node_Id) is
2180 Designator : constant Entity_Id := Defining_Entity (N);
2181 Typ : Entity_Id := Empty;
2184 -- Normal case where result definition does not indicate an error
2186 if Result_Definition (N) /= Error then
2187 if Nkind (Result_Definition (N)) = N_Access_Definition then
2188 Check_SPARK_05_Restriction
2189 ("access result is not allowed", Result_Definition (N));
2191 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
2194 AD : constant Node_Id :=
2195 Access_To_Subprogram_Definition (Result_Definition (N));
2197 if Present (AD) and then Protected_Present (AD) then
2198 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2200 Typ := Access_Definition (N, Result_Definition (N));
2204 Set_Parent (Typ, Result_Definition (N));
2205 Set_Is_Local_Anonymous_Access (Typ);
2206 Set_Etype (Designator, Typ);
2208 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2210 Null_Exclusion_Static_Checks (N);
2212 -- Subtype_Mark case
2215 Find_Type (Result_Definition (N));
2216 Typ := Entity (Result_Definition (N));
2217 Set_Etype (Designator, Typ);
2219 -- Unconstrained array as result is not allowed in SPARK
2221 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
2222 Check_SPARK_05_Restriction
2223 ("returning an unconstrained array is not allowed",
2224 Result_Definition (N));
2227 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
2229 Null_Exclusion_Static_Checks (N);
2231 -- If a null exclusion is imposed on the result type, then create
2232 -- a null-excluding itype (an access subtype) and use it as the
2233 -- function's Etype. Note that the null exclusion checks are done
2234 -- right before this, because they don't get applied to types that
2235 -- do not come from source.
2237 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
2238 Set_Etype (Designator,
2239 Create_Null_Excluding_Itype
2242 Scope_Id => Scope (Current_Scope)));
2244 -- The new subtype must be elaborated before use because
2245 -- it is visible outside of the function. However its base
2246 -- type may not be frozen yet, so the reference that will
2247 -- force elaboration must be attached to the freezing of
2250 -- If the return specification appears on a proper body,
2251 -- the subtype will have been created already on the spec.
2253 if Is_Frozen (Typ) then
2254 if Nkind (Parent (N)) = N_Subprogram_Body
2255 and then Nkind (Parent (Parent (N))) = N_Subunit
2259 Build_Itype_Reference (Etype (Designator), Parent (N));
2263 Ensure_Freeze_Node (Typ);
2266 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
2268 Set_Itype (IR, Etype (Designator));
2269 Append_Freeze_Actions (Typ, New_List (IR));
2274 Set_Etype (Designator, Typ);
2277 if Ekind (Typ) = E_Incomplete_Type
2278 or else (Is_Class_Wide_Type (Typ)
2279 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
2281 -- AI05-0151: Tagged incomplete types are allowed in all formal
2282 -- parts. Untagged incomplete types are not allowed in bodies.
2283 -- As a consequence, limited views cannot appear in a basic
2284 -- declaration that is itself within a body, because there is
2285 -- no point at which the non-limited view will become visible.
2287 if Ada_Version >= Ada_2012 then
2288 if From_Limited_With (Typ) and then In_Package_Body then
2290 ("invalid use of incomplete type&",
2291 Result_Definition (N), Typ);
2293 -- The return type of a subprogram body cannot be of a
2294 -- formal incomplete type.
2296 elsif Is_Generic_Type (Typ)
2297 and then Nkind (Parent (N)) = N_Subprogram_Body
2300 ("return type cannot be a formal incomplete type",
2301 Result_Definition (N));
2303 elsif Is_Class_Wide_Type (Typ)
2304 and then Is_Generic_Type (Root_Type (Typ))
2305 and then Nkind (Parent (N)) = N_Subprogram_Body
2308 ("return type cannot be a formal incomplete type",
2309 Result_Definition (N));
2311 elsif Is_Tagged_Type (Typ) then
2314 -- Use is legal in a thunk generated for an operation
2315 -- inherited from a progenitor.
2317 elsif Is_Thunk (Designator)
2318 and then Present (Non_Limited_View (Typ))
2322 elsif Nkind (Parent (N)) = N_Subprogram_Body
2323 or else Nkind_In (Parent (Parent (N)), N_Accept_Statement,
2327 ("invalid use of untagged incomplete type&",
2331 -- The type must be completed in the current package. This
2332 -- is checked at the end of the package declaration when
2333 -- Taft-amendment types are identified. If the return type
2334 -- is class-wide, there is no required check, the type can
2335 -- be a bona fide TAT.
2337 if Ekind (Scope (Current_Scope)) = E_Package
2338 and then In_Private_Part (Scope (Current_Scope))
2339 and then not Is_Class_Wide_Type (Typ)
2341 Append_Elmt (Designator, Private_Dependents (Typ));
2346 ("invalid use of incomplete type&", Designator, Typ);
2351 -- Case where result definition does indicate an error
2354 Set_Etype (Designator, Any_Type);
2356 end Analyze_Return_Type;
2358 -----------------------------
2359 -- Analyze_Subprogram_Body --
2360 -----------------------------
2362 procedure Analyze_Subprogram_Body (N : Node_Id) is
2363 Loc : constant Source_Ptr := Sloc (N);
2364 Body_Spec : constant Node_Id := Specification (N);
2365 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2368 if Debug_Flag_C then
2369 Write_Str ("==> subprogram body ");
2370 Write_Name (Chars (Body_Id));
2371 Write_Str (" from ");
2372 Write_Location (Loc);
2377 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
2379 -- The real work is split out into the helper, so it can do "return;"
2380 -- without skipping the debug output:
2382 Analyze_Subprogram_Body_Helper (N);
2384 if Debug_Flag_C then
2386 Write_Str ("<== subprogram body ");
2387 Write_Name (Chars (Body_Id));
2388 Write_Str (" from ");
2389 Write_Location (Loc);
2392 end Analyze_Subprogram_Body;
2394 ------------------------------------
2395 -- Analyze_Subprogram_Body_Helper --
2396 ------------------------------------
2398 -- This procedure is called for regular subprogram bodies, generic bodies,
2399 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2400 -- specification matters, and is used to create a proper declaration for
2401 -- the subprogram, or to perform conformance checks.
2403 -- WARNING: This routine manages Ghost regions. Return statements must be
2404 -- replaced by gotos which jump to the end of the routine and restore the
2407 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2408 Body_Spec : Node_Id := Specification (N);
2409 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2410 Loc : constant Source_Ptr := Sloc (N);
2411 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2413 Conformant : Boolean;
2414 Desig_View : Entity_Id := Empty;
2415 Exch_Views : Elist_Id := No_Elist;
2417 Mask_Types : Elist_Id := No_Elist;
2418 Prot_Typ : Entity_Id := Empty;
2419 Spec_Decl : Node_Id := Empty;
2420 Spec_Id : Entity_Id;
2422 Last_Real_Spec_Entity : Entity_Id := Empty;
2423 -- When we analyze a separate spec, the entity chain ends up containing
2424 -- the formals, as well as any itypes generated during analysis of the
2425 -- default expressions for parameters, or the arguments of associated
2426 -- precondition/postcondition pragmas (which are analyzed in the context
2427 -- of the spec since they have visibility on formals).
2429 -- These entities belong with the spec and not the body. However we do
2430 -- the analysis of the body in the context of the spec (again to obtain
2431 -- visibility to the formals), and all the entities generated during
2432 -- this analysis end up also chained to the entity chain of the spec.
2433 -- But they really belong to the body, and there is circuitry to move
2434 -- them from the spec to the body.
2436 -- However, when we do this move, we don't want to move the real spec
2437 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2438 -- variable points to the last real spec entity, so we only move those
2439 -- chained beyond that point. It is initialized to Empty to deal with
2440 -- the case where there is no separate spec.
2442 function Body_Has_Contract return Boolean;
2443 -- Check whether unanalyzed body has an aspect or pragma that may
2444 -- generate a SPARK contract.
2446 function Body_Has_SPARK_Mode_On return Boolean;
2447 -- Check whether SPARK_Mode On applies to the subprogram body, either
2448 -- because it is specified directly on the body, or because it is
2449 -- inherited from the enclosing subprogram or package.
2451 procedure Build_Subprogram_Declaration;
2452 -- Create a matching subprogram declaration for subprogram body N
2454 procedure Check_Anonymous_Return;
2455 -- Ada 2005: if a function returns an access type that denotes a task,
2456 -- or a type that contains tasks, we must create a master entity for
2457 -- the anonymous type, which typically will be used in an allocator
2458 -- in the body of the function.
2460 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2461 -- Look ahead to recognize a pragma that may appear after the body.
2462 -- If there is a previous spec, check that it appears in the same
2463 -- declarative part. If the pragma is Inline_Always, perform inlining
2464 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2465 -- If the body acts as a spec, and inlining is required, we create a
2466 -- subprogram declaration for it, in order to attach the body to inline.
2467 -- If pragma does not appear after the body, check whether there is
2468 -- an inline pragma before any local declarations.
2470 procedure Check_Missing_Return;
2471 -- Checks for a function with a no return statements, and also performs
2472 -- the warning checks implemented by Check_Returns. In formal mode, also
2473 -- verify that a function ends with a RETURN and that a procedure does
2474 -- not contain any RETURN.
2476 function Disambiguate_Spec return Entity_Id;
2477 -- When a primitive is declared between the private view and the full
2478 -- view of a concurrent type which implements an interface, a special
2479 -- mechanism is used to find the corresponding spec of the primitive
2482 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id;
2483 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2484 -- incomplete types coming from a limited context and replace their
2485 -- limited views with the non-limited ones. Return the list of changes
2486 -- to be used to undo the transformation.
2488 function Is_Private_Concurrent_Primitive
2489 (Subp_Id : Entity_Id) return Boolean;
2490 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2491 -- type that implements an interface and has a private view.
2493 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id;
2494 -- N is the body generated for an expression function that is not a
2495 -- completion and Spec_Id the defining entity of its spec. Mark all
2496 -- the not-yet-frozen types referenced by the simple return statement
2497 -- of the function as formally frozen.
2499 procedure Restore_Limited_Views (Restore_List : Elist_Id);
2500 -- Undo the transformation done by Exchange_Limited_Views.
2502 procedure Set_Trivial_Subprogram (N : Node_Id);
2503 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2504 -- subprogram whose body is being analyzed. N is the statement node
2505 -- causing the flag to be set, if the following statement is a return
2506 -- of an entity, we mark the entity as set in source to suppress any
2507 -- warning on the stylized use of function stubs with a dummy return.
2509 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id);
2510 -- Undo the transformation done by Mask_Unfrozen_Types
2512 procedure Verify_Overriding_Indicator;
2513 -- If there was a previous spec, the entity has been entered in the
2514 -- current scope previously. If the body itself carries an overriding
2515 -- indicator, check that it is consistent with the known status of the
2518 -----------------------
2519 -- Body_Has_Contract --
2520 -----------------------
2522 function Body_Has_Contract return Boolean is
2523 Decls : constant List_Id := Declarations (N);
2527 -- Check for aspects that may generate a contract
2529 if Present (Aspect_Specifications (N)) then
2530 Item := First (Aspect_Specifications (N));
2531 while Present (Item) loop
2532 if Is_Subprogram_Contract_Annotation (Item) then
2540 -- Check for pragmas that may generate a contract
2542 if Present (Decls) then
2543 Item := First (Decls);
2544 while Present (Item) loop
2545 if Nkind (Item) = N_Pragma
2546 and then Is_Subprogram_Contract_Annotation (Item)
2556 end Body_Has_Contract;
2558 ----------------------------
2559 -- Body_Has_SPARK_Mode_On --
2560 ----------------------------
2562 function Body_Has_SPARK_Mode_On return Boolean is
2563 Decls : constant List_Id := Declarations (N);
2567 -- Check for SPARK_Mode aspect
2569 if Present (Aspect_Specifications (N)) then
2570 Item := First (Aspect_Specifications (N));
2571 while Present (Item) loop
2572 if Get_Aspect_Id (Item) = Aspect_SPARK_Mode then
2573 return Get_SPARK_Mode_From_Annotation (Item) = On;
2580 -- Check for SPARK_Mode pragma
2582 if Present (Decls) then
2583 Item := First (Decls);
2584 while Present (Item) loop
2586 -- Pragmas that apply to a subprogram body are usually grouped
2587 -- together. Look for a potential pragma SPARK_Mode among them.
2589 if Nkind (Item) = N_Pragma then
2590 if Get_Pragma_Id (Item) = Pragma_SPARK_Mode then
2591 return Get_SPARK_Mode_From_Annotation (Item) = On;
2594 -- Otherwise the first non-pragma declarative item terminates
2595 -- the region where pragma SPARK_Mode may appear.
2605 -- Otherwise, the applicable SPARK_Mode is inherited from the
2606 -- enclosing subprogram or package.
2608 return SPARK_Mode = On;
2609 end Body_Has_SPARK_Mode_On;
2611 ----------------------------------
2612 -- Build_Subprogram_Declaration --
2613 ----------------------------------
2615 procedure Build_Subprogram_Declaration is
2616 procedure Move_Pragmas (From : Node_Id; To : Node_Id);
2617 -- Relocate certain categorization pragmas from the declarative list
2618 -- of subprogram body From and insert them after node To. The pragmas
2621 -- Volatile_Function
2622 -- Also copy pragma SPARK_Mode if present in the declarative list
2623 -- of subprogram body From and insert it after node To. This pragma
2624 -- should not be moved, as it applies to the body too.
2630 procedure Move_Pragmas (From : Node_Id; To : Node_Id) is
2632 Next_Decl : Node_Id;
2635 pragma Assert (Nkind (From) = N_Subprogram_Body);
2637 -- The destination node must be part of a list, as the pragmas are
2638 -- inserted after it.
2640 pragma Assert (Is_List_Member (To));
2642 -- Inspect the declarations of the subprogram body looking for
2643 -- specific pragmas.
2645 Decl := First (Declarations (N));
2646 while Present (Decl) loop
2647 Next_Decl := Next (Decl);
2649 if Nkind (Decl) = N_Pragma then
2650 if Pragma_Name_Unmapped (Decl) = Name_SPARK_Mode then
2651 Insert_After (To, New_Copy_Tree (Decl));
2653 elsif Nam_In (Pragma_Name_Unmapped (Decl),
2655 Name_Volatile_Function)
2658 Insert_After (To, Decl);
2669 Subp_Decl : Node_Id;
2671 -- Start of processing for Build_Subprogram_Declaration
2674 -- Create a matching subprogram spec using the profile of the body.
2675 -- The structure of the tree is identical, but has new entities for
2676 -- the defining unit name and formal parameters.
2679 Make_Subprogram_Declaration (Loc,
2680 Specification => Copy_Subprogram_Spec (Body_Spec));
2681 Set_Comes_From_Source (Subp_Decl, True);
2683 -- Relocate the aspects and relevant pragmas from the subprogram body
2684 -- to the generated spec because it acts as the initial declaration.
2686 Insert_Before (N, Subp_Decl);
2687 Move_Aspects (N, To => Subp_Decl);
2688 Move_Pragmas (N, To => Subp_Decl);
2690 -- Ensure that the generated corresponding spec and original body
2691 -- share the same SPARK_Mode pragma or aspect. As a result, both have
2692 -- the same SPARK_Mode attributes, and the global SPARK_Mode value is
2693 -- correctly set for local subprograms.
2695 Copy_SPARK_Mode_Aspect (Subp_Decl, To => N);
2697 Analyze (Subp_Decl);
2699 -- Propagate the attributes Rewritten_For_C and Corresponding_Proc to
2700 -- the body since the expander may generate calls using that entity.
2701 -- Required to ensure that Expand_Call rewrites calls to this
2702 -- function by calls to the built procedure.
2704 if Modify_Tree_For_C
2705 and then Nkind (Body_Spec) = N_Function_Specification
2707 Rewritten_For_C (Defining_Entity (Specification (Subp_Decl)))
2709 Set_Rewritten_For_C (Defining_Entity (Body_Spec));
2710 Set_Corresponding_Procedure (Defining_Entity (Body_Spec),
2711 Corresponding_Procedure
2712 (Defining_Entity (Specification (Subp_Decl))));
2715 -- Analyze any relocated source pragmas or pragmas created for aspect
2718 Decl := Next (Subp_Decl);
2719 while Present (Decl) loop
2721 -- Stop the search for pragmas once the body has been reached as
2722 -- this terminates the region where pragmas may appear.
2727 elsif Nkind (Decl) = N_Pragma then
2734 Spec_Id := Defining_Entity (Subp_Decl);
2735 Set_Corresponding_Spec (N, Spec_Id);
2737 -- Mark the generated spec as a source construct to ensure that all
2738 -- calls to it are properly registered in ALI files for GNATprove.
2740 Set_Comes_From_Source (Spec_Id, True);
2742 -- Ensure that the specs of the subprogram declaration and its body
2743 -- are identical, otherwise they will appear non-conformant due to
2744 -- rewritings in the default values of formal parameters.
2746 Body_Spec := Copy_Subprogram_Spec (Body_Spec);
2747 Set_Specification (N, Body_Spec);
2748 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2749 end Build_Subprogram_Declaration;
2751 ----------------------------
2752 -- Check_Anonymous_Return --
2753 ----------------------------
2755 procedure Check_Anonymous_Return is
2761 if Present (Spec_Id) then
2767 if Ekind (Scop) = E_Function
2768 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2769 and then not Is_Thunk (Scop)
2771 -- Skip internally built functions which handle the case of
2772 -- a null access (see Expand_Interface_Conversion)
2774 and then not (Is_Interface (Designated_Type (Etype (Scop)))
2775 and then not Comes_From_Source (Parent (Scop)))
2777 and then (Has_Task (Designated_Type (Etype (Scop)))
2779 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2781 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2782 and then Expander_Active
2784 -- Avoid cases with no tasking support
2786 and then RTE_Available (RE_Current_Master)
2787 and then not Restriction_Active (No_Task_Hierarchy)
2790 Make_Object_Declaration (Loc,
2791 Defining_Identifier =>
2792 Make_Defining_Identifier (Loc, Name_uMaster),
2793 Constant_Present => True,
2794 Object_Definition =>
2795 New_Occurrence_Of (RTE (RE_Master_Id), Loc),
2797 Make_Explicit_Dereference (Loc,
2798 New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
2800 if Present (Declarations (N)) then
2801 Prepend (Decl, Declarations (N));
2803 Set_Declarations (N, New_List (Decl));
2806 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2807 Set_Has_Master_Entity (Scop);
2809 -- Now mark the containing scope as a task master
2812 while Nkind (Par) /= N_Compilation_Unit loop
2813 Par := Parent (Par);
2814 pragma Assert (Present (Par));
2816 -- If we fall off the top, we are at the outer level, and
2817 -- the environment task is our effective master, so nothing
2821 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2823 Set_Is_Task_Master (Par, True);
2828 end Check_Anonymous_Return;
2830 -------------------------
2831 -- Check_Inline_Pragma --
2832 -------------------------
2834 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2838 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2839 -- True when N is a pragma Inline or Inline_Always that applies
2840 -- to this subprogram.
2842 -----------------------
2843 -- Is_Inline_Pragma --
2844 -----------------------
2846 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2848 if Nkind (N) = N_Pragma
2850 (Pragma_Name_Unmapped (N) = Name_Inline_Always
2851 or else (Pragma_Name_Unmapped (N) = Name_Inline
2853 (Front_End_Inlining or else Optimization_Level > 0)))
2854 and then Present (Pragma_Argument_Associations (N))
2857 Pragma_Arg : Node_Id :=
2858 Expression (First (Pragma_Argument_Associations (N)));
2860 if Nkind (Pragma_Arg) = N_Selected_Component then
2861 Pragma_Arg := Selector_Name (Pragma_Arg);
2864 return Chars (Pragma_Arg) = Chars (Body_Id);
2870 end Is_Inline_Pragma;
2872 -- Start of processing for Check_Inline_Pragma
2875 if not Expander_Active then
2879 if Is_List_Member (N)
2880 and then Present (Next (N))
2881 and then Is_Inline_Pragma (Next (N))
2885 elsif Nkind (N) /= N_Subprogram_Body_Stub
2886 and then Present (Declarations (N))
2887 and then Is_Inline_Pragma (First (Declarations (N)))
2889 Prag := First (Declarations (N));
2895 if Present (Prag) then
2896 if Present (Spec_Id) then
2897 if Is_List_Member (N)
2898 and then Is_List_Member (Unit_Declaration_Node (Spec_Id))
2899 and then In_Same_List (N, Unit_Declaration_Node (Spec_Id))
2905 -- Create a subprogram declaration, to make treatment uniform.
2906 -- Make the sloc of the subprogram name that of the entity in
2907 -- the body, so that style checks find identical strings.
2910 Subp : constant Entity_Id :=
2911 Make_Defining_Identifier
2912 (Sloc (Body_Id), Chars (Body_Id));
2913 Decl : constant Node_Id :=
2914 Make_Subprogram_Declaration (Loc,
2916 New_Copy_Tree (Specification (N)));
2919 -- Link the body and the generated spec
2921 Set_Corresponding_Body (Decl, Body_Id);
2922 Set_Corresponding_Spec (N, Subp);
2924 Set_Defining_Unit_Name (Specification (Decl), Subp);
2926 -- To ensure proper coverage when body is inlined, indicate
2927 -- whether the subprogram comes from source.
2929 Set_Comes_From_Source (Subp, Comes_From_Source (N));
2931 if Present (First_Formal (Body_Id)) then
2932 Plist := Copy_Parameter_List (Body_Id);
2933 Set_Parameter_Specifications
2934 (Specification (Decl), Plist);
2937 -- Move aspects to the new spec
2939 if Has_Aspects (N) then
2940 Move_Aspects (N, To => Decl);
2943 Insert_Before (N, Decl);
2946 Set_Has_Pragma_Inline (Subp);
2948 if Pragma_Name (Prag) = Name_Inline_Always then
2949 Set_Is_Inlined (Subp);
2950 Set_Has_Pragma_Inline_Always (Subp);
2953 -- Prior to copying the subprogram body to create a template
2954 -- for it for subsequent inlining, remove the pragma from
2955 -- the current body so that the copy that will produce the
2956 -- new body will start from a completely unanalyzed tree.
2958 if Nkind (Parent (Prag)) = N_Subprogram_Body then
2959 Rewrite (Prag, Make_Null_Statement (Sloc (Prag)));
2966 end Check_Inline_Pragma;
2968 --------------------------
2969 -- Check_Missing_Return --
2970 --------------------------
2972 procedure Check_Missing_Return is
2974 Missing_Ret : Boolean;
2977 if Nkind (Body_Spec) = N_Function_Specification then
2978 if Present (Spec_Id) then
2984 if Return_Present (Id) then
2985 Check_Returns (HSS, 'F', Missing_Ret);
2988 Set_Has_Missing_Return (Id);
2991 -- Within a premature instantiation of a package with no body, we
2992 -- build completions of the functions therein, with a Raise
2993 -- statement. No point in complaining about a missing return in
2996 elsif Ekind (Id) = E_Function
2997 and then In_Instance
2998 and then Present (Statements (HSS))
2999 and then Nkind (First (Statements (HSS))) = N_Raise_Program_Error
3003 elsif Is_Generic_Subprogram (Id)
3004 or else not Is_Machine_Code_Subprogram (Id)
3006 Error_Msg_N ("missing RETURN statement in function body", N);
3009 -- If procedure with No_Return, check returns
3011 elsif Nkind (Body_Spec) = N_Procedure_Specification
3012 and then Present (Spec_Id)
3013 and then No_Return (Spec_Id)
3015 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
3018 -- Special checks in SPARK mode
3020 if Nkind (Body_Spec) = N_Function_Specification then
3022 -- In SPARK mode, last statement of a function should be a return
3025 Stat : constant Node_Id := Last_Source_Statement (HSS);
3028 and then not Nkind_In (Stat, N_Simple_Return_Statement,
3029 N_Extended_Return_Statement)
3031 Check_SPARK_05_Restriction
3032 ("last statement in function should be RETURN", Stat);
3036 -- In SPARK mode, verify that a procedure has no return
3038 elsif Nkind (Body_Spec) = N_Procedure_Specification then
3039 if Present (Spec_Id) then
3045 -- Would be nice to point to return statement here, can we
3046 -- borrow the Check_Returns procedure here ???
3048 if Return_Present (Id) then
3049 Check_SPARK_05_Restriction
3050 ("procedure should not have RETURN", N);
3053 end Check_Missing_Return;
3055 -----------------------
3056 -- Disambiguate_Spec --
3057 -----------------------
3059 function Disambiguate_Spec return Entity_Id is
3060 Priv_Spec : Entity_Id;
3063 procedure Replace_Types (To_Corresponding : Boolean);
3064 -- Depending on the flag, replace the type of formal parameters of
3065 -- Body_Id if it is a concurrent type implementing interfaces with
3066 -- the corresponding record type or the other way around.
3068 procedure Replace_Types (To_Corresponding : Boolean) is
3070 Formal_Typ : Entity_Id;
3073 Formal := First_Formal (Body_Id);
3074 while Present (Formal) loop
3075 Formal_Typ := Etype (Formal);
3077 if Is_Class_Wide_Type (Formal_Typ) then
3078 Formal_Typ := Root_Type (Formal_Typ);
3081 -- From concurrent type to corresponding record
3083 if To_Corresponding then
3084 if Is_Concurrent_Type (Formal_Typ)
3085 and then Present (Corresponding_Record_Type (Formal_Typ))
3088 (Corresponding_Record_Type (Formal_Typ)))
3091 Corresponding_Record_Type (Formal_Typ));
3094 -- From corresponding record to concurrent type
3097 if Is_Concurrent_Record_Type (Formal_Typ)
3098 and then Present (Interfaces (Formal_Typ))
3101 Corresponding_Concurrent_Type (Formal_Typ));
3105 Next_Formal (Formal);
3109 -- Start of processing for Disambiguate_Spec
3112 -- Try to retrieve the specification of the body as is. All error
3113 -- messages are suppressed because the body may not have a spec in
3114 -- its current state.
3116 Spec_N := Find_Corresponding_Spec (N, False);
3118 -- It is possible that this is the body of a primitive declared
3119 -- between a private and a full view of a concurrent type. The
3120 -- controlling parameter of the spec carries the concurrent type,
3121 -- not the corresponding record type as transformed by Analyze_
3122 -- Subprogram_Specification. In such cases, we undo the change
3123 -- made by the analysis of the specification and try to find the
3126 -- Note that wrappers already have their corresponding specs and
3127 -- bodies set during their creation, so if the candidate spec is
3128 -- a wrapper, then we definitely need to swap all types to their
3129 -- original concurrent status.
3132 or else Is_Primitive_Wrapper (Spec_N)
3134 -- Restore all references of corresponding record types to the
3135 -- original concurrent types.
3137 Replace_Types (To_Corresponding => False);
3138 Priv_Spec := Find_Corresponding_Spec (N, False);
3140 -- The current body truly belongs to a primitive declared between
3141 -- a private and a full view. We leave the modified body as is,
3142 -- and return the true spec.
3144 if Present (Priv_Spec)
3145 and then Is_Private_Primitive (Priv_Spec)
3150 -- In case that this is some sort of error, restore the original
3151 -- state of the body.
3153 Replace_Types (To_Corresponding => True);
3157 end Disambiguate_Spec;
3159 ----------------------------
3160 -- Exchange_Limited_Views --
3161 ----------------------------
3163 function Exchange_Limited_Views (Subp_Id : Entity_Id) return Elist_Id is
3164 Result : Elist_Id := No_Elist;
3166 procedure Detect_And_Exchange (Id : Entity_Id);
3167 -- Determine whether Id's type denotes an incomplete type associated
3168 -- with a limited with clause and exchange the limited view with the
3169 -- non-limited one when available. Note that the non-limited view
3170 -- may exist because of a with_clause in another unit in the context,
3171 -- but cannot be used because the current view of the enclosing unit
3172 -- is still a limited view.
3174 -------------------------
3175 -- Detect_And_Exchange --
3176 -------------------------
3178 procedure Detect_And_Exchange (Id : Entity_Id) is
3179 Typ : constant Entity_Id := Etype (Id);
3181 if From_Limited_With (Typ)
3182 and then Has_Non_Limited_View (Typ)
3183 and then not From_Limited_With (Scope (Typ))
3186 Result := New_Elmt_List;
3189 Prepend_Elmt (Typ, Result);
3190 Prepend_Elmt (Id, Result);
3191 Set_Etype (Id, Non_Limited_View (Typ));
3193 end Detect_And_Exchange;
3199 -- Start of processing for Exchange_Limited_Views
3202 -- Do not process subprogram bodies as they already use the non-
3203 -- limited view of types.
3205 if not Ekind_In (Subp_Id, E_Function, E_Procedure) then
3209 -- Examine all formals and swap views when applicable
3211 Formal := First_Formal (Subp_Id);
3212 while Present (Formal) loop
3213 Detect_And_Exchange (Formal);
3215 Next_Formal (Formal);
3218 -- Process the return type of a function
3220 if Ekind (Subp_Id) = E_Function then
3221 Detect_And_Exchange (Subp_Id);
3225 end Exchange_Limited_Views;
3227 -------------------------------------
3228 -- Is_Private_Concurrent_Primitive --
3229 -------------------------------------
3231 function Is_Private_Concurrent_Primitive
3232 (Subp_Id : Entity_Id) return Boolean
3234 Formal_Typ : Entity_Id;
3237 if Present (First_Formal (Subp_Id)) then
3238 Formal_Typ := Etype (First_Formal (Subp_Id));
3240 if Is_Concurrent_Record_Type (Formal_Typ) then
3241 if Is_Class_Wide_Type (Formal_Typ) then
3242 Formal_Typ := Root_Type (Formal_Typ);
3245 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
3248 -- The type of the first formal is a concurrent tagged type with
3252 Is_Concurrent_Type (Formal_Typ)
3253 and then Is_Tagged_Type (Formal_Typ)
3254 and then Has_Private_Declaration (Formal_Typ);
3258 end Is_Private_Concurrent_Primitive;
3260 -------------------------
3261 -- Mask_Unfrozen_Types --
3262 -------------------------
3264 function Mask_Unfrozen_Types (Spec_Id : Entity_Id) return Elist_Id is
3265 Result : Elist_Id := No_Elist;
3267 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result;
3268 -- Mask all types referenced in the subtree rooted at Node
3270 --------------------
3271 -- Mask_Type_Refs --
3272 --------------------
3274 function Mask_Type_Refs (Node : Node_Id) return Traverse_Result is
3275 procedure Mask_Type (Typ : Entity_Id);
3276 -- ??? what does this do?
3282 procedure Mask_Type (Typ : Entity_Id) is
3284 -- Skip Itypes created by the preanalysis
3287 and then Scope_Within_Or_Same (Scope (Typ), Spec_Id)
3292 if not Is_Frozen (Typ) then
3293 Set_Is_Frozen (Typ);
3294 Append_New_Elmt (Typ, Result);
3298 -- Start of processing for Mask_Type_Refs
3301 if Is_Entity_Name (Node) and then Present (Entity (Node)) then
3302 Mask_Type (Etype (Entity (Node)));
3304 if Ekind_In (Entity (Node), E_Component, E_Discriminant) then
3305 Mask_Type (Scope (Entity (Node)));
3308 elsif Nkind_In (Node, N_Aggregate, N_Null, N_Type_Conversion)
3309 and then Present (Etype (Node))
3311 Mask_Type (Etype (Node));
3317 procedure Mask_References is new Traverse_Proc (Mask_Type_Refs);
3321 Return_Stmt : constant Node_Id :=
3322 First (Statements (Handled_Statement_Sequence (N)));
3324 -- Start of processing for Mask_Unfrozen_Types
3327 pragma Assert (Nkind (Return_Stmt) = N_Simple_Return_Statement);
3329 Mask_References (Expression (Return_Stmt));
3332 end Mask_Unfrozen_Types;
3334 ---------------------------
3335 -- Restore_Limited_Views --
3336 ---------------------------
3338 procedure Restore_Limited_Views (Restore_List : Elist_Id) is
3339 Elmt : Elmt_Id := First_Elmt (Restore_List);
3343 while Present (Elmt) loop
3346 Set_Etype (Id, Node (Elmt));
3349 end Restore_Limited_Views;
3351 ----------------------------
3352 -- Set_Trivial_Subprogram --
3353 ----------------------------
3355 procedure Set_Trivial_Subprogram (N : Node_Id) is
3356 Nxt : constant Node_Id := Next (N);
3359 Set_Is_Trivial_Subprogram (Body_Id);
3361 if Present (Spec_Id) then
3362 Set_Is_Trivial_Subprogram (Spec_Id);
3366 and then Nkind (Nxt) = N_Simple_Return_Statement
3367 and then No (Next (Nxt))
3368 and then Present (Expression (Nxt))
3369 and then Is_Entity_Name (Expression (Nxt))
3371 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
3373 end Set_Trivial_Subprogram;
3375 ---------------------------
3376 -- Unmask_Unfrozen_Types --
3377 ---------------------------
3379 procedure Unmask_Unfrozen_Types (Unmask_List : Elist_Id) is
3380 Elmt : Elmt_Id := First_Elmt (Unmask_List);
3383 while Present (Elmt) loop
3384 Set_Is_Frozen (Node (Elmt), False);
3387 end Unmask_Unfrozen_Types;
3389 ---------------------------------
3390 -- Verify_Overriding_Indicator --
3391 ---------------------------------
3393 procedure Verify_Overriding_Indicator is
3395 if Must_Override (Body_Spec) then
3396 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
3397 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3401 elsif not Present (Overridden_Operation (Spec_Id)) then
3403 ("subprogram& is not overriding", Body_Spec, Spec_Id);
3405 -- Overriding indicators aren't allowed for protected subprogram
3406 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3407 -- this to a warning if -gnatd.E is enabled.
3409 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3410 Error_Msg_Warn := Error_To_Warning;
3412 ("<<overriding indicator not allowed for protected "
3413 & "subprogram body", Body_Spec);
3416 elsif Must_Not_Override (Body_Spec) then
3417 if Present (Overridden_Operation (Spec_Id)) then
3419 ("subprogram& overrides inherited operation",
3420 Body_Spec, Spec_Id);
3422 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
3423 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
3426 ("subprogram& overrides predefined operator ",
3427 Body_Spec, Spec_Id);
3429 -- Overriding indicators aren't allowed for protected subprogram
3430 -- bodies (see the Confirmation in Ada Comment AC95-00213). Change
3431 -- this to a warning if -gnatd.E is enabled.
3433 elsif Ekind (Scope (Spec_Id)) = E_Protected_Type then
3434 Error_Msg_Warn := Error_To_Warning;
3437 ("<<overriding indicator not allowed "
3438 & "for protected subprogram body", Body_Spec);
3440 -- If this is not a primitive operation, then the overriding
3441 -- indicator is altogether illegal.
3443 elsif not Is_Primitive (Spec_Id) then
3445 ("overriding indicator only allowed "
3446 & "if subprogram is primitive", Body_Spec);
3449 -- If checking the style rule and the operation overrides, then
3450 -- issue a warning about a missing overriding_indicator. Protected
3451 -- subprogram bodies are excluded from this style checking, since
3452 -- they aren't primitives (even though their declarations can
3453 -- override) and aren't allowed to have an overriding_indicator.
3456 and then Present (Overridden_Operation (Spec_Id))
3457 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
3459 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3460 Style.Missing_Overriding (N, Body_Id);
3463 and then Can_Override_Operator (Spec_Id)
3464 and then not In_Predefined_Unit (Spec_Id)
3466 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
3467 Style.Missing_Overriding (N, Body_Id);
3469 end Verify_Overriding_Indicator;
3473 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3474 Saved_ISMP : constant Boolean :=
3475 Ignore_SPARK_Mode_Pragmas_In_Instance;
3476 -- Save the Ghost and SPARK mode-related data to restore on exit
3478 -- Start of processing for Analyze_Subprogram_Body_Helper
3481 -- A [generic] subprogram body freezes the contract of the nearest
3482 -- enclosing package body and all other contracts encountered in the
3483 -- same declarative part up to and excluding the subprogram body:
3485 -- package body Nearest_Enclosing_Package
3486 -- with Refined_State => (State => Constit)
3490 -- procedure Freezes_Enclosing_Package_Body
3491 -- with Refined_Depends => (Input => Constit) ...
3493 -- This ensures that any annotations referenced by the contract of the
3494 -- [generic] subprogram body are available. This form of freezing is
3495 -- decoupled from the usual Freeze_xxx mechanism because it must also
3496 -- work in the context of generics where normal freezing is disabled.
3498 -- Only bodies coming from source should cause this type of freezing.
3499 -- Expression functions that act as bodies and complete an initial
3500 -- declaration must be included in this category, hence the use of
3503 if Comes_From_Source (Original_Node (N)) then
3504 Freeze_Previous_Contracts (N);
3507 -- Generic subprograms are handled separately. They always have a
3508 -- generic specification. Determine whether current scope has a
3509 -- previous declaration.
3511 -- If the subprogram body is defined within an instance of the same
3512 -- name, the instance appears as a package renaming, and will be hidden
3513 -- within the subprogram.
3515 if Present (Prev_Id)
3516 and then not Is_Overloadable (Prev_Id)
3517 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
3518 or else Comes_From_Source (Prev_Id))
3520 if Is_Generic_Subprogram (Prev_Id) then
3523 -- A subprogram body is Ghost when it is stand alone and subject
3524 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3525 -- the mode now to ensure that any nodes generated during analysis
3526 -- and expansion are properly marked as Ghost.
3528 Mark_And_Set_Ghost_Body (N, Spec_Id);
3530 -- If the body completes the initial declaration of a compilation
3531 -- unit which is subject to pragma Elaboration_Checks, set the
3532 -- model specified by the pragma because it applies to all parts
3535 Install_Elaboration_Model (Spec_Id);
3537 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3538 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3540 Analyze_Generic_Subprogram_Body (N, Spec_Id);
3542 if Nkind (N) = N_Subprogram_Body then
3543 HSS := Handled_Statement_Sequence (N);
3544 Check_Missing_Return;
3549 -- Otherwise a previous entity conflicts with the subprogram name.
3550 -- Attempting to enter name will post error.
3553 Enter_Name (Body_Id);
3557 -- Non-generic case, find the subprogram declaration, if one was seen,
3558 -- or enter new overloaded entity in the current scope. If the
3559 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
3560 -- part of the context of one of its subunits. No need to redo the
3563 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
3567 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
3569 if Nkind (N) = N_Subprogram_Body_Stub
3570 or else No (Corresponding_Spec (N))
3572 if Is_Private_Concurrent_Primitive (Body_Id) then
3573 Spec_Id := Disambiguate_Spec;
3575 -- A subprogram body is Ghost when it is stand alone and
3576 -- subject to pragma Ghost or when the corresponding spec is
3577 -- Ghost. Set the mode now to ensure that any nodes generated
3578 -- during analysis and expansion are properly marked as Ghost.
3580 Mark_And_Set_Ghost_Body (N, Spec_Id);
3582 -- If the body completes a compilation unit which is subject
3583 -- to pragma Elaboration_Checks, set the model specified by
3584 -- the pragma because it applies to all parts of the unit.
3586 Install_Elaboration_Model (Spec_Id);
3589 Spec_Id := Find_Corresponding_Spec (N);
3591 -- A subprogram body is Ghost when it is stand alone and
3592 -- subject to pragma Ghost or when the corresponding spec is
3593 -- Ghost. Set the mode now to ensure that any nodes generated
3594 -- during analysis and expansion are properly marked as Ghost.
3596 Mark_And_Set_Ghost_Body (N, Spec_Id);
3598 -- If the body completes a compilation unit which is subject
3599 -- to pragma Elaboration_Checks, set the model specified by
3600 -- the pragma because it applies to all parts of the unit.
3602 Install_Elaboration_Model (Spec_Id);
3604 -- In GNATprove mode, if the body has no previous spec, create
3605 -- one so that the inlining machinery can operate properly.
3606 -- Transfer aspects, if any, to the new spec, so that they
3607 -- are legal and can be processed ahead of the body.
3608 -- We make two copies of the given spec, one for the new
3609 -- declaration, and one for the body.
3611 if No (Spec_Id) and then GNATprove_Mode
3613 -- Inlining does not apply during pre-analysis of code
3615 and then Full_Analysis
3617 -- Inlining only applies to full bodies, not stubs
3619 and then Nkind (N) /= N_Subprogram_Body_Stub
3621 -- Inlining only applies to bodies in the source code, not to
3622 -- those generated by the compiler. In particular, expression
3623 -- functions, whose body is generated by the compiler, are
3624 -- treated specially by GNATprove.
3626 and then Comes_From_Source (Body_Id)
3628 -- This cannot be done for a compilation unit, which is not
3629 -- in a context where we can insert a new spec.
3631 and then Is_List_Member (N)
3633 -- Inlining only applies to subprograms without contracts,
3634 -- as a contract is a sign that GNATprove should perform a
3635 -- modular analysis of the subprogram instead of a contextual
3636 -- analysis at each call site. The same test is performed in
3637 -- Inline.Can_Be_Inlined_In_GNATprove_Mode. It is repeated
3638 -- here in another form (because the contract has not been
3639 -- attached to the body) to avoid front-end errors in case
3640 -- pragmas are used instead of aspects, because the
3641 -- corresponding pragmas in the body would not be transferred
3642 -- to the spec, leading to legality errors.
3644 and then not Body_Has_Contract
3645 and then not Inside_A_Generic
3647 Build_Subprogram_Declaration;
3649 -- If this is a function that returns a constrained array, and
3650 -- we are generating SPARK_For_C, create subprogram declaration
3651 -- to simplify subsequent C generation.
3654 and then Modify_Tree_For_C
3655 and then Nkind (Body_Spec) = N_Function_Specification
3656 and then Is_Array_Type (Etype (Body_Id))
3657 and then Is_Constrained (Etype (Body_Id))
3659 Build_Subprogram_Declaration;
3663 -- If this is a duplicate body, no point in analyzing it
3665 if Error_Posted (N) then
3669 -- A subprogram body should cause freezing of its own declaration,
3670 -- but if there was no previous explicit declaration, then the
3671 -- subprogram will get frozen too late (there may be code within
3672 -- the body that depends on the subprogram having been frozen,
3673 -- such as uses of extra formals), so we force it to be frozen
3674 -- here. Same holds if the body and spec are compilation units.
3675 -- Finally, if the return type is an anonymous access to protected
3676 -- subprogram, it must be frozen before the body because its
3677 -- expansion has generated an equivalent type that is used when
3678 -- elaborating the body.
3680 -- An exception in the case of Ada 2012, AI05-177: The bodies
3681 -- created for expression functions do not freeze.
3684 and then Nkind (Original_Node (N)) /= N_Expression_Function
3686 Freeze_Before (N, Body_Id);
3688 elsif Nkind (Parent (N)) = N_Compilation_Unit then
3689 Freeze_Before (N, Spec_Id);
3691 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
3692 Freeze_Before (N, Etype (Body_Id));
3696 Spec_Id := Corresponding_Spec (N);
3698 -- A subprogram body is Ghost when it is stand alone and subject
3699 -- to pragma Ghost or when the corresponding spec is Ghost. Set
3700 -- the mode now to ensure that any nodes generated during analysis
3701 -- and expansion are properly marked as Ghost.
3703 Mark_And_Set_Ghost_Body (N, Spec_Id);
3705 -- If the body completes the initial declaration of a compilation
3706 -- unit which is subject to pragma Elaboration_Checks, set the
3707 -- model specified by the pragma because it applies to all parts
3710 Install_Elaboration_Model (Spec_Id);
3714 -- Previously we scanned the body to look for nested subprograms, and
3715 -- rejected an inline directive if nested subprograms were present,
3716 -- because the back-end would generate conflicting symbols for the
3717 -- nested bodies. This is now unnecessary.
3719 -- Look ahead to recognize a pragma Inline that appears after the body
3721 Check_Inline_Pragma (Spec_Id);
3723 -- Deal with special case of a fully private operation in the body of
3724 -- the protected type. We must create a declaration for the subprogram,
3725 -- in order to attach the protected subprogram that will be used in
3726 -- internal calls. We exclude compiler generated bodies from the
3727 -- expander since the issue does not arise for those cases.
3730 and then Comes_From_Source (N)
3731 and then Is_Protected_Type (Current_Scope)
3733 Spec_Id := Build_Private_Protected_Declaration (N);
3736 -- If we are generating C and this is a function returning a constrained
3737 -- array type for which we must create a procedure with an extra out
3738 -- parameter, build and analyze the body now. The procedure declaration
3739 -- has already been created. We reuse the source body of the function,
3740 -- because in an instance it may contain global references that cannot
3741 -- be reanalyzed. The source function itself is not used any further,
3742 -- so we mark it as having a completion. If the subprogram is a stub the
3743 -- transformation is done later, when the proper body is analyzed.
3746 and then Modify_Tree_For_C
3747 and then Present (Spec_Id)
3748 and then Ekind (Spec_Id) = E_Function
3749 and then Nkind (N) /= N_Subprogram_Body_Stub
3750 and then Rewritten_For_C (Spec_Id)
3752 Set_Has_Completion (Spec_Id);
3754 Rewrite (N, Build_Procedure_Body_Form (Spec_Id, N));
3757 -- The entity for the created procedure must remain invisible, so it
3758 -- does not participate in resolution of subsequent references to the
3761 Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
3765 -- If a separate spec is present, then deal with freezing issues
3767 if Present (Spec_Id) then
3768 Spec_Decl := Unit_Declaration_Node (Spec_Id);
3769 Verify_Overriding_Indicator;
3771 -- In general, the spec will be frozen when we start analyzing the
3772 -- body. However, for internally generated operations, such as
3773 -- wrapper functions for inherited operations with controlling
3774 -- results, the spec may not have been frozen by the time we expand
3775 -- the freeze actions that include the bodies. In particular, extra
3776 -- formals for accessibility or for return-in-place may need to be
3777 -- generated. Freeze nodes, if any, are inserted before the current
3778 -- body. These freeze actions are also needed in ASIS mode and in
3779 -- Compile_Only mode to enable the proper back-end type annotations.
3780 -- They are necessary in any case to insure order of elaboration
3783 if not Is_Frozen (Spec_Id)
3784 and then (Expander_Active
3786 or else (Operating_Mode = Check_Semantics
3787 and then Serious_Errors_Detected = 0))
3789 -- The body generated for an expression function that is not a
3790 -- completion is a freeze point neither for the profile nor for
3791 -- anything else. That's why, in order to prevent any freezing
3792 -- during analysis, we need to mask types declared outside the
3793 -- expression that are not yet frozen.
3795 if Nkind (N) = N_Subprogram_Body
3796 and then Was_Expression_Function (N)
3797 and then not Has_Completion (Spec_Id)
3799 Set_Is_Frozen (Spec_Id);
3800 Mask_Types := Mask_Unfrozen_Types (Spec_Id);
3802 Set_Has_Delayed_Freeze (Spec_Id);
3803 Freeze_Before (N, Spec_Id);
3808 -- If the subprogram has a class-wide clone, build its body as a copy
3809 -- of the original body, and rewrite body of original subprogram as a
3810 -- wrapper that calls the clone.
3812 if Present (Spec_Id)
3813 and then Present (Class_Wide_Clone (Spec_Id))
3814 and then (Comes_From_Source (N) or else Was_Expression_Function (N))
3816 Build_Class_Wide_Clone_Body (Spec_Id, N);
3818 -- This is the new body for the existing primitive operation
3820 Rewrite (N, Build_Class_Wide_Clone_Call
3821 (Sloc (N), New_List, Spec_Id, Parent (Spec_Id)));
3822 Set_Has_Completion (Spec_Id, False);
3827 -- Place subprogram on scope stack, and make formals visible. If there
3828 -- is a spec, the visible entity remains that of the spec.
3830 if Present (Spec_Id) then
3831 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
3833 if Is_Child_Unit (Spec_Id) then
3834 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
3838 Style.Check_Identifier (Body_Id, Spec_Id);
3841 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
3842 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
3844 if Is_Abstract_Subprogram (Spec_Id) then
3845 Error_Msg_N ("an abstract subprogram cannot have a body", N);
3849 Set_Convention (Body_Id, Convention (Spec_Id));
3850 Set_Has_Completion (Spec_Id);
3852 if Is_Protected_Type (Scope (Spec_Id)) then
3853 Prot_Typ := Scope (Spec_Id);
3856 -- If this is a body generated for a renaming, do not check for
3857 -- full conformance. The check is redundant, because the spec of
3858 -- the body is a copy of the spec in the renaming declaration,
3859 -- and the test can lead to spurious errors on nested defaults.
3861 if Present (Spec_Decl)
3862 and then not Comes_From_Source (N)
3864 (Nkind (Original_Node (Spec_Decl)) =
3865 N_Subprogram_Renaming_Declaration
3866 or else (Present (Corresponding_Body (Spec_Decl))
3868 Nkind (Unit_Declaration_Node
3869 (Corresponding_Body (Spec_Decl))) =
3870 N_Subprogram_Renaming_Declaration))
3874 -- Conversely, the spec may have been generated for specless body
3875 -- with an inline pragma. The entity comes from source, which is
3876 -- both semantically correct and necessary for proper inlining.
3877 -- The subprogram declaration itself is not in the source.
3879 elsif Comes_From_Source (N)
3880 and then Present (Spec_Decl)
3881 and then not Comes_From_Source (Spec_Decl)
3882 and then Has_Pragma_Inline (Spec_Id)
3889 Fully_Conformant, True, Conformant, Body_Id);
3892 -- If the body is not fully conformant, we have to decide if we
3893 -- should analyze it or not. If it has a really messed up profile
3894 -- then we probably should not analyze it, since we will get too
3895 -- many bogus messages.
3897 -- Our decision is to go ahead in the non-fully conformant case
3898 -- only if it is at least mode conformant with the spec. Note
3899 -- that the call to Check_Fully_Conformant has issued the proper
3900 -- error messages to complain about the lack of conformance.
3903 and then not Mode_Conformant (Body_Id, Spec_Id)
3909 if Spec_Id /= Body_Id then
3910 Reference_Body_Formals (Spec_Id, Body_Id);
3913 Set_Ekind (Body_Id, E_Subprogram_Body);
3915 if Nkind (N) = N_Subprogram_Body_Stub then
3916 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
3921 Set_Corresponding_Spec (N, Spec_Id);
3923 -- Ada 2005 (AI-345): If the operation is a primitive operation
3924 -- of a concurrent type, the type of the first parameter has been
3925 -- replaced with the corresponding record, which is the proper
3926 -- run-time structure to use. However, within the body there may
3927 -- be uses of the formals that depend on primitive operations
3928 -- of the type (in particular calls in prefixed form) for which
3929 -- we need the original concurrent type. The operation may have
3930 -- several controlling formals, so the replacement must be done
3933 if Comes_From_Source (Spec_Id)
3934 and then Present (First_Entity (Spec_Id))
3935 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
3936 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
3937 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
3938 and then Present (Corresponding_Concurrent_Type
3939 (Etype (First_Entity (Spec_Id))))
3942 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
3946 Form := First_Formal (Spec_Id);
3947 while Present (Form) loop
3948 if Etype (Form) = Typ then
3949 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
3957 -- Make the formals visible, and place subprogram on scope stack.
3958 -- This is also the point at which we set Last_Real_Spec_Entity
3959 -- to mark the entities which will not be moved to the body.
3961 Install_Formals (Spec_Id);
3962 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
3964 -- Within an instance, add local renaming declarations so that
3965 -- gdb can retrieve the values of actuals more easily. This is
3966 -- only relevant if generating code (and indeed we definitely
3967 -- do not want these definitions -gnatc mode, because that would
3970 if Is_Generic_Instance (Spec_Id)
3971 and then Is_Wrapper_Package (Current_Scope)
3972 and then Expander_Active
3974 Build_Subprogram_Instance_Renamings (N, Current_Scope);
3977 Push_Scope (Spec_Id);
3979 -- Make sure that the subprogram is immediately visible. For
3980 -- child units that have no separate spec this is indispensable.
3981 -- Otherwise it is safe albeit redundant.
3983 Set_Is_Immediately_Visible (Spec_Id);
3986 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
3987 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
3988 Set_Scope (Body_Id, Scope (Spec_Id));
3990 -- Case of subprogram body with no previous spec
3993 -- Check for style warning required
3997 -- Only apply check for source level subprograms for which checks
3998 -- have not been suppressed.
4000 and then Comes_From_Source (Body_Id)
4001 and then not Suppress_Style_Checks (Body_Id)
4003 -- No warnings within an instance
4005 and then not In_Instance
4007 -- No warnings for expression functions
4009 and then Nkind (Original_Node (N)) /= N_Expression_Function
4011 Style.Body_With_No_Spec (N);
4014 New_Overloaded_Entity (Body_Id);
4016 if Nkind (N) /= N_Subprogram_Body_Stub then
4017 Set_Acts_As_Spec (N);
4018 Generate_Definition (Body_Id);
4020 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
4022 -- If the body is an entry wrapper created for an entry with
4023 -- preconditions, it must be compiled in the context of the
4024 -- enclosing synchronized object, because it may mention other
4025 -- operations of the type.
4027 if Is_Entry_Wrapper (Body_Id) then
4029 Prot : constant Entity_Id := Etype (First_Entity (Body_Id));
4032 Install_Declarations (Prot);
4036 Install_Formals (Body_Id);
4038 Push_Scope (Body_Id);
4041 -- For stubs and bodies with no previous spec, generate references to
4044 Generate_Reference_To_Formals (Body_Id);
4047 -- Entry barrier functions are generated outside the protected type and
4048 -- should not carry the SPARK_Mode of the enclosing context.
4050 if Nkind (N) = N_Subprogram_Body
4051 and then Is_Entry_Barrier_Function (N)
4055 -- The body is generated as part of expression function expansion. When
4056 -- the expression function appears in the visible declarations of a
4057 -- package, the body is added to the private declarations. Since both
4058 -- declarative lists may be subject to a different SPARK_Mode, inherit
4059 -- the mode of the spec.
4061 -- package P with SPARK_Mode is
4062 -- function Expr_Func ... is (...); -- original
4063 -- [function Expr_Func ...;] -- generated spec
4066 -- pragma SPARK_Mode (Off);
4067 -- [function Expr_Func ... is return ...;] -- generated body
4068 -- end P; -- mode is ON
4070 elsif not Comes_From_Source (N)
4071 and then Present (Spec_Id)
4072 and then Is_Expression_Function (Spec_Id)
4074 Set_SPARK_Pragma (Body_Id, SPARK_Pragma (Spec_Id));
4075 Set_SPARK_Pragma_Inherited
4076 (Body_Id, SPARK_Pragma_Inherited (Spec_Id));
4078 -- Set the SPARK_Mode from the current context (may be overwritten later
4079 -- with explicit pragma). Exclude the case where the SPARK_Mode appears
4080 -- initially on a stand-alone subprogram body, but is then relocated to
4081 -- a generated corresponding spec. In this scenario the mode is shared
4082 -- between the spec and body.
4084 elsif No (SPARK_Pragma (Body_Id)) then
4085 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
4086 Set_SPARK_Pragma_Inherited (Body_Id);
4089 -- A subprogram body may be instantiated or inlined at a later pass.
4090 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when it
4091 -- applied to the initial declaration of the body.
4093 if Present (Spec_Id) then
4094 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
4095 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4099 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in
4100 -- case the body is instantiated or inlined later and out of context.
4101 -- The body uses this attribute to restore the value of the global
4104 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4105 Set_Ignore_SPARK_Mode_Pragmas (Body_Id);
4107 elsif Ignore_SPARK_Mode_Pragmas (Body_Id) then
4108 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
4112 -- If this is the proper body of a stub, we must verify that the stub
4113 -- conforms to the body, and to the previous spec if one was present.
4114 -- We know already that the body conforms to that spec. This test is
4115 -- only required for subprograms that come from source.
4117 if Nkind (Parent (N)) = N_Subunit
4118 and then Comes_From_Source (N)
4119 and then not Error_Posted (Body_Id)
4120 and then Nkind (Corresponding_Stub (Parent (N))) =
4121 N_Subprogram_Body_Stub
4124 Old_Id : constant Entity_Id :=
4126 (Specification (Corresponding_Stub (Parent (N))));
4128 Conformant : Boolean := False;
4131 if No (Spec_Id) then
4132 Check_Fully_Conformant (Body_Id, Old_Id);
4136 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
4138 if not Conformant then
4140 -- The stub was taken to be a new declaration. Indicate that
4143 Set_Has_Completion (Old_Id, False);
4149 Set_Has_Completion (Body_Id);
4150 Check_Eliminated (Body_Id);
4152 -- Analyze any aspect specifications that appear on the subprogram body
4153 -- stub. Stop the analysis now as the stub does not have a declarative
4154 -- or a statement part, and it cannot be inlined.
4156 if Nkind (N) = N_Subprogram_Body_Stub then
4157 if Has_Aspects (N) then
4158 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4166 -- Note: Normally we don't do any inlining if expansion is off, since
4167 -- we won't generate code in any case. An exception arises in GNATprove
4168 -- mode where we want to expand some calls in place, even with expansion
4169 -- disabled, since the inlining eases formal verification.
4171 if not GNATprove_Mode
4172 and then Expander_Active
4173 and then Serious_Errors_Detected = 0
4174 and then Present (Spec_Id)
4175 and then Has_Pragma_Inline (Spec_Id)
4177 -- Legacy implementation (relying on front-end inlining)
4179 if not Back_End_Inlining then
4180 if (Has_Pragma_Inline_Always (Spec_Id)
4181 and then not Opt.Disable_FE_Inline_Always)
4182 or else (Front_End_Inlining
4183 and then not Opt.Disable_FE_Inline)
4185 Build_Body_To_Inline (N, Spec_Id);
4188 -- New implementation (relying on back-end inlining)
4191 if Has_Pragma_Inline_Always (Spec_Id)
4192 or else Optimization_Level > 0
4194 -- Handle function returning an unconstrained type
4196 if Comes_From_Source (Body_Id)
4197 and then Ekind (Spec_Id) = E_Function
4198 and then Returns_Unconstrained_Type (Spec_Id)
4200 -- If function builds in place, i.e. returns a limited type,
4201 -- inlining cannot be done.
4203 and then not Is_Limited_Type (Etype (Spec_Id))
4205 Check_And_Split_Unconstrained_Function (N, Spec_Id, Body_Id);
4209 Subp_Body : constant Node_Id :=
4210 Unit_Declaration_Node (Body_Id);
4211 Subp_Decl : constant List_Id := Declarations (Subp_Body);
4214 -- Do not pass inlining to the backend if the subprogram
4215 -- has declarations or statements which cannot be inlined
4216 -- by the backend. This check is done here to emit an
4217 -- error instead of the generic warning message reported
4218 -- by the GCC backend (ie. "function might not be
4221 if Present (Subp_Decl)
4222 and then Has_Excluded_Declaration (Spec_Id, Subp_Decl)
4226 elsif Has_Excluded_Statement
4229 (Handled_Statement_Sequence (Subp_Body)))
4233 -- If the backend inlining is available then at this
4234 -- stage we only have to mark the subprogram as inlined.
4235 -- The expander will take care of registering it in the
4236 -- table of subprograms inlined by the backend a part of
4237 -- processing calls to it (cf. Expand_Call)
4240 Set_Is_Inlined (Spec_Id);
4247 -- In GNATprove mode, inline only when there is a separate subprogram
4248 -- declaration for now, as inlining of subprogram bodies acting as
4249 -- declarations, or subprogram stubs, are not supported by front-end
4250 -- inlining. This inlining should occur after analysis of the body, so
4251 -- that it is known whether the value of SPARK_Mode, which can be
4252 -- defined by a pragma inside the body, is applicable to the body.
4253 -- Inlining can be disabled with switch -gnatdm
4255 elsif GNATprove_Mode
4256 and then Full_Analysis
4257 and then not Inside_A_Generic
4258 and then Present (Spec_Id)
4260 Nkind (Unit_Declaration_Node (Spec_Id)) = N_Subprogram_Declaration
4261 and then Body_Has_SPARK_Mode_On
4262 and then Can_Be_Inlined_In_GNATprove_Mode (Spec_Id, Body_Id)
4263 and then not Body_Has_Contract
4264 and then not Debug_Flag_M
4266 Build_Body_To_Inline (N, Spec_Id);
4269 -- When generating code, inherited pre/postconditions are handled when
4270 -- expanding the corresponding contract.
4272 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
4273 -- of the specification we have to install the private withed units.
4274 -- This holds for child units as well.
4276 if Is_Compilation_Unit (Body_Id)
4277 or else Nkind (Parent (N)) = N_Compilation_Unit
4279 Install_Private_With_Clauses (Body_Id);
4282 Check_Anonymous_Return;
4284 -- Set the Protected_Formal field of each extra formal of the protected
4285 -- subprogram to reference the corresponding extra formal of the
4286 -- subprogram that implements it. For regular formals this occurs when
4287 -- the protected subprogram's declaration is expanded, but the extra
4288 -- formals don't get created until the subprogram is frozen. We need to
4289 -- do this before analyzing the protected subprogram's body so that any
4290 -- references to the original subprogram's extra formals will be changed
4291 -- refer to the implementing subprogram's formals (see Expand_Formal).
4293 if Present (Spec_Id)
4294 and then Is_Protected_Type (Scope (Spec_Id))
4295 and then Present (Protected_Body_Subprogram (Spec_Id))
4298 Impl_Subp : constant Entity_Id :=
4299 Protected_Body_Subprogram (Spec_Id);
4300 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
4301 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
4304 while Present (Prot_Ext_Formal) loop
4305 pragma Assert (Present (Impl_Ext_Formal));
4306 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
4307 Next_Formal_With_Extras (Prot_Ext_Formal);
4308 Next_Formal_With_Extras (Impl_Ext_Formal);
4313 -- Now we can go on to analyze the body
4315 HSS := Handled_Statement_Sequence (N);
4316 Set_Actual_Subtypes (N, Current_Scope);
4318 -- Add a declaration for the Protection object, renaming declarations
4319 -- for discriminals and privals and finally a declaration for the entry
4320 -- family index (if applicable). This form of early expansion is done
4321 -- when the Expander is active because Install_Private_Data_Declarations
4322 -- references entities which were created during regular expansion. The
4323 -- subprogram entity must come from source, and not be an internally
4324 -- generated subprogram.
4327 and then Present (Prot_Typ)
4328 and then Present (Spec_Id)
4329 and then Comes_From_Source (Spec_Id)
4330 and then not Is_Eliminated (Spec_Id)
4332 Install_Private_Data_Declarations
4333 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
4336 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
4337 -- may now appear in parameter and result profiles. Since the analysis
4338 -- of a subprogram body may use the parameter and result profile of the
4339 -- spec, swap any limited views with their non-limited counterpart.
4341 if Ada_Version >= Ada_2012 and then Present (Spec_Id) then
4342 Exch_Views := Exchange_Limited_Views (Spec_Id);
4345 -- If the return type is an anonymous access type whose designated type
4346 -- is the limited view of a class-wide type and the non-limited view is
4347 -- available, update the return type accordingly.
4349 if Ada_Version >= Ada_2005 and then Present (Spec_Id) then
4355 Rtyp := Etype (Spec_Id);
4357 if Ekind (Rtyp) = E_Anonymous_Access_Type then
4358 Etyp := Directly_Designated_Type (Rtyp);
4360 if Is_Class_Wide_Type (Etyp)
4361 and then From_Limited_With (Etyp)
4364 Set_Directly_Designated_Type (Rtyp, Available_View (Etyp));
4370 -- Analyze any aspect specifications that appear on the subprogram body
4372 if Has_Aspects (N) then
4373 Analyze_Aspects_On_Subprogram_Body_Or_Stub (N);
4376 Analyze_Declarations (Declarations (N));
4378 -- Verify that the SPARK_Mode of the body agrees with that of its spec
4380 if Present (Spec_Id) and then Present (SPARK_Pragma (Body_Id)) then
4381 if Present (SPARK_Pragma (Spec_Id)) then
4382 if Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) = Off
4384 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
4386 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4387 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
4388 Error_Msg_Sloc := Sloc (SPARK_Pragma (Spec_Id));
4390 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
4393 elsif Nkind (Parent (Parent (Spec_Id))) = N_Subprogram_Body_Stub then
4397 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
4398 Error_Msg_N ("incorrect application of SPARK_Mode #", N);
4399 Error_Msg_Sloc := Sloc (Spec_Id);
4401 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
4405 -- A subprogram body freezes its own contract. Analyze the contract
4406 -- after the declarations of the body have been processed as pragmas
4407 -- are now chained on the contract of the subprogram body.
4409 Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id);
4411 -- Check completion, and analyze the statements
4414 Inspect_Deferred_Constant_Completion (Declarations (N));
4417 -- Deal with end of scope processing for the body
4419 Process_End_Label (HSS, 't', Current_Scope);
4420 Update_Use_Clause_Chain;
4423 -- If we are compiling an entry wrapper, remove the enclosing
4424 -- synchronized object from the stack.
4426 if Is_Entry_Wrapper (Body_Id) then
4430 Check_Subprogram_Order (N);
4431 Set_Analyzed (Body_Id);
4433 -- If we have a separate spec, then the analysis of the declarations
4434 -- caused the entities in the body to be chained to the spec id, but
4435 -- we want them chained to the body id. Only the formal parameters
4436 -- end up chained to the spec id in this case.
4438 if Present (Spec_Id) then
4440 -- We must conform to the categorization of our spec
4442 Validate_Categorization_Dependency (N, Spec_Id);
4444 -- And if this is a child unit, the parent units must conform
4446 if Is_Child_Unit (Spec_Id) then
4447 Validate_Categorization_Dependency
4448 (Unit_Declaration_Node (Spec_Id), Spec_Id);
4451 -- Here is where we move entities from the spec to the body
4453 -- Case where there are entities that stay with the spec
4455 if Present (Last_Real_Spec_Entity) then
4457 -- No body entities (happens when the only real spec entities come
4458 -- from precondition and postcondition pragmas).
4460 if No (Last_Entity (Body_Id)) then
4461 Set_First_Entity (Body_Id, Next_Entity (Last_Real_Spec_Entity));
4463 -- Body entities present (formals), so chain stuff past them
4467 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
4470 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
4471 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4472 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
4474 -- Case where there are no spec entities, in this case there can be
4475 -- no body entities either, so just move everything.
4477 -- If the body is generated for an expression function, it may have
4478 -- been preanalyzed already, if 'access was applied to it.
4481 if Nkind (Original_Node (Unit_Declaration_Node (Spec_Id))) /=
4482 N_Expression_Function
4484 pragma Assert (No (Last_Entity (Body_Id)));
4488 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
4489 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
4490 Set_First_Entity (Spec_Id, Empty);
4491 Set_Last_Entity (Spec_Id, Empty);
4494 -- Otherwise the body does not complete a previous declaration. Check
4495 -- the categorization of the body against the units it withs.
4498 Validate_Categorization_Dependency (N, Body_Id);
4501 Check_Missing_Return;
4503 -- Now we are going to check for variables that are never modified in
4504 -- the body of the procedure. But first we deal with a special case
4505 -- where we want to modify this check. If the body of the subprogram
4506 -- starts with a raise statement or its equivalent, or if the body
4507 -- consists entirely of a null statement, then it is pretty obvious that
4508 -- it is OK to not reference the parameters. For example, this might be
4509 -- the following common idiom for a stubbed function: statement of the
4510 -- procedure raises an exception. In particular this deals with the
4511 -- common idiom of a stubbed function, which appears something like:
4513 -- function F (A : Integer) return Some_Type;
4516 -- raise Program_Error;
4520 -- Here the purpose of X is simply to satisfy the annoying requirement
4521 -- in Ada that there be at least one return, and we certainly do not
4522 -- want to go posting warnings on X that it is not initialized. On
4523 -- the other hand, if X is entirely unreferenced that should still
4526 -- What we do is to detect these cases, and if we find them, flag the
4527 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
4528 -- suppress unwanted warnings. For the case of the function stub above
4529 -- we have a special test to set X as apparently assigned to suppress
4536 -- Skip call markers installed by the ABE mechanism, labels, and
4537 -- Push_xxx_Error_Label to find the first real statement.
4539 Stm := First (Statements (HSS));
4540 while Nkind_In (Stm, N_Call_Marker, N_Label)
4541 or else Nkind (Stm) in N_Push_xxx_Label
4546 -- Do the test on the original statement before expansion
4549 Ostm : constant Node_Id := Original_Node (Stm);
4552 -- If explicit raise statement, turn on flag
4554 if Nkind (Ostm) = N_Raise_Statement then
4555 Set_Trivial_Subprogram (Stm);
4557 -- If null statement, and no following statements, turn on flag
4559 elsif Nkind (Stm) = N_Null_Statement
4560 and then Comes_From_Source (Stm)
4561 and then No (Next (Stm))
4563 Set_Trivial_Subprogram (Stm);
4565 -- Check for explicit call cases which likely raise an exception
4567 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
4568 if Is_Entity_Name (Name (Ostm)) then
4570 Ent : constant Entity_Id := Entity (Name (Ostm));
4573 -- If the procedure is marked No_Return, then likely it
4574 -- raises an exception, but in any case it is not coming
4575 -- back here, so turn on the flag.
4578 and then Ekind (Ent) = E_Procedure
4579 and then No_Return (Ent)
4581 Set_Trivial_Subprogram (Stm);
4589 -- Check for variables that are never modified
4596 -- If there is a separate spec, then transfer Never_Set_In_Source
4597 -- flags from out parameters to the corresponding entities in the
4598 -- body. The reason we do that is we want to post error flags on
4599 -- the body entities, not the spec entities.
4601 if Present (Spec_Id) then
4602 E1 := First_Entity (Spec_Id);
4603 while Present (E1) loop
4604 if Ekind (E1) = E_Out_Parameter then
4605 E2 := First_Entity (Body_Id);
4606 while Present (E2) loop
4607 exit when Chars (E1) = Chars (E2);
4611 if Present (E2) then
4612 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
4620 -- Check references in body
4622 Check_References (Body_Id);
4625 -- Check for nested subprogram, and mark outer level subprogram if so
4631 if Present (Spec_Id) then
4638 Ent := Enclosing_Subprogram (Ent);
4639 exit when No (Ent) or else Is_Subprogram (Ent);
4642 if Present (Ent) then
4643 Set_Has_Nested_Subprogram (Ent);
4647 -- Restore the limited views in the spec, if any, to let the back end
4648 -- process it without running into circularities.
4650 if Exch_Views /= No_Elist then
4651 Restore_Limited_Views (Exch_Views);
4654 if Mask_Types /= No_Elist then
4655 Unmask_Unfrozen_Types (Mask_Types);
4658 if Present (Desig_View) then
4659 Set_Directly_Designated_Type (Etype (Spec_Id), Desig_View);
4663 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
4664 Restore_Ghost_Mode (Saved_GM);
4665 end Analyze_Subprogram_Body_Helper;
4667 ------------------------------------
4668 -- Analyze_Subprogram_Declaration --
4669 ------------------------------------
4671 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
4672 Scop : constant Entity_Id := Current_Scope;
4673 Designator : Entity_Id;
4675 Is_Completion : Boolean;
4676 -- Indicates whether a null procedure declaration is a completion
4679 -- Null procedures are not allowed in SPARK
4681 if Nkind (Specification (N)) = N_Procedure_Specification
4682 and then Null_Present (Specification (N))
4684 Check_SPARK_05_Restriction ("null procedure is not allowed", N);
4686 -- Null procedures are allowed in protected types, following the
4687 -- recent AI12-0147.
4689 if Is_Protected_Type (Current_Scope)
4690 and then Ada_Version < Ada_2012
4692 Error_Msg_N ("protected operation cannot be a null procedure", N);
4695 Analyze_Null_Procedure (N, Is_Completion);
4697 -- The null procedure acts as a body, nothing further is needed
4699 if Is_Completion then
4704 Designator := Analyze_Subprogram_Specification (Specification (N));
4706 -- A reference may already have been generated for the unit name, in
4707 -- which case the following call is redundant. However it is needed for
4708 -- declarations that are the rewriting of an expression function.
4710 Generate_Definition (Designator);
4712 -- Set the SPARK mode from the current context (may be overwritten later
4713 -- with explicit pragma). This is not done for entry barrier functions
4714 -- because they are generated outside the protected type and should not
4715 -- carry the mode of the enclosing context.
4717 if Nkind (N) = N_Subprogram_Declaration
4718 and then Is_Entry_Barrier_Function (N)
4723 Set_SPARK_Pragma (Designator, SPARK_Mode_Pragma);
4724 Set_SPARK_Pragma_Inherited (Designator);
4727 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
4728 -- the body of this subprogram is instantiated or inlined later and out
4729 -- of context. The body uses this attribute to restore the value of the
4732 if Ignore_SPARK_Mode_Pragmas_In_Instance then
4733 Set_Ignore_SPARK_Mode_Pragmas (Designator);
4736 -- Preserve relevant elaboration-related attributes of the context which
4737 -- are no longer available or very expensive to recompute once analysis,
4738 -- resolution, and expansion are over.
4740 Mark_Elaboration_Attributes
4741 (N_Id => Designator,
4744 if Debug_Flag_C then
4745 Write_Str ("==> subprogram spec ");
4746 Write_Name (Chars (Designator));
4747 Write_Str (" from ");
4748 Write_Location (Sloc (N));
4753 Validate_RCI_Subprogram_Declaration (N);
4754 New_Overloaded_Entity (Designator);
4755 Check_Delayed_Subprogram (Designator);
4757 -- If the type of the first formal of the current subprogram is a non-
4758 -- generic tagged private type, mark the subprogram as being a private
4759 -- primitive. Ditto if this is a function with controlling result, and
4760 -- the return type is currently private. In both cases, the type of the
4761 -- controlling argument or result must be in the current scope for the
4762 -- operation to be primitive.
4764 if Has_Controlling_Result (Designator)
4765 and then Is_Private_Type (Etype (Designator))
4766 and then Scope (Etype (Designator)) = Current_Scope
4767 and then not Is_Generic_Actual_Type (Etype (Designator))
4769 Set_Is_Private_Primitive (Designator);
4771 elsif Present (First_Formal (Designator)) then
4773 Formal_Typ : constant Entity_Id :=
4774 Etype (First_Formal (Designator));
4776 Set_Is_Private_Primitive (Designator,
4777 Is_Tagged_Type (Formal_Typ)
4778 and then Scope (Formal_Typ) = Current_Scope
4779 and then Is_Private_Type (Formal_Typ)
4780 and then not Is_Generic_Actual_Type (Formal_Typ));
4784 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
4787 if Ada_Version >= Ada_2005
4788 and then Comes_From_Source (N)
4789 and then Is_Dispatching_Operation (Designator)
4796 if Has_Controlling_Result (Designator) then
4797 Etyp := Etype (Designator);
4800 E := First_Entity (Designator);
4802 and then Is_Formal (E)
4803 and then not Is_Controlling_Formal (E)
4811 if Is_Access_Type (Etyp) then
4812 Etyp := Directly_Designated_Type (Etyp);
4815 if Is_Interface (Etyp)
4816 and then not Is_Abstract_Subprogram (Designator)
4817 and then not (Ekind (Designator) = E_Procedure
4818 and then Null_Present (Specification (N)))
4820 Error_Msg_Name_1 := Chars (Defining_Entity (N));
4822 -- Specialize error message based on procedures vs. functions,
4823 -- since functions can't be null subprograms.
4825 if Ekind (Designator) = E_Procedure then
4827 ("interface procedure % must be abstract or null", N);
4830 ("interface function % must be abstract", N);
4836 -- What is the following code for, it used to be
4838 -- ??? Set_Suppress_Elaboration_Checks
4839 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
4841 -- The following seems equivalent, but a bit dubious
4843 if Elaboration_Checks_Suppressed (Designator) then
4844 Set_Kill_Elaboration_Checks (Designator);
4847 -- For a compilation unit, set body required. This flag will only be
4848 -- reset if a valid Import or Interface pragma is processed later on.
4850 if Nkind (Parent (N)) = N_Compilation_Unit then
4851 Set_Body_Required (Parent (N), True);
4853 if Ada_Version >= Ada_2005
4854 and then Nkind (Specification (N)) = N_Procedure_Specification
4855 and then Null_Present (Specification (N))
4858 ("null procedure cannot be declared at library level", N);
4862 Generate_Reference_To_Formals (Designator);
4863 Check_Eliminated (Designator);
4865 if Debug_Flag_C then
4867 Write_Str ("<== subprogram spec ");
4868 Write_Name (Chars (Designator));
4869 Write_Str (" from ");
4870 Write_Location (Sloc (N));
4874 -- Indicate that this is a protected operation, because it may be used
4875 -- in subsequent declarations within the protected type.
4877 if Is_Protected_Type (Current_Scope) then
4878 Set_Convention (Designator, Convention_Protected);
4881 List_Inherited_Pre_Post_Aspects (Designator);
4883 -- Process the aspects before establishing the proper categorization in
4884 -- case the subprogram is a compilation unit and one of its aspects is
4885 -- converted into a categorization pragma.
4887 if Has_Aspects (N) then
4888 Analyze_Aspect_Specifications (N, Designator);
4891 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
4892 Set_Categorization_From_Scope (Designator, Scop);
4894 -- Otherwise the unit is a compilation unit and/or a child unit. Set the
4895 -- proper categorization of the unit based on its pragmas.
4898 Push_Scope (Designator);
4899 Set_Categorization_From_Pragmas (N);
4900 Validate_Categorization_Dependency (N, Designator);
4903 end Analyze_Subprogram_Declaration;
4905 --------------------------------------
4906 -- Analyze_Subprogram_Specification --
4907 --------------------------------------
4909 -- Reminder: N here really is a subprogram specification (not a subprogram
4910 -- declaration). This procedure is called to analyze the specification in
4911 -- both subprogram bodies and subprogram declarations (specs).
4913 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
4914 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean;
4915 -- Determine whether entity E denotes the spec or body of an invariant
4918 ------------------------------------
4919 -- Is_Invariant_Procedure_Or_Body --
4920 ------------------------------------
4922 function Is_Invariant_Procedure_Or_Body (E : Entity_Id) return Boolean is
4923 Decl : constant Node_Id := Unit_Declaration_Node (E);
4927 if Nkind (Decl) = N_Subprogram_Body then
4928 Spec := Corresponding_Spec (Decl);
4935 and then Ekind (Spec) = E_Procedure
4936 and then (Is_Partial_Invariant_Procedure (Spec)
4937 or else Is_Invariant_Procedure (Spec));
4938 end Is_Invariant_Procedure_Or_Body;
4942 Designator : constant Entity_Id := Defining_Entity (N);
4943 Formals : constant List_Id := Parameter_Specifications (N);
4945 -- Start of processing for Analyze_Subprogram_Specification
4948 -- User-defined operator is not allowed in SPARK, except as a renaming
4950 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
4951 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
4953 Check_SPARK_05_Restriction
4954 ("user-defined operator is not allowed", N);
4957 -- Proceed with analysis. Do not emit a cross-reference entry if the
4958 -- specification comes from an expression function, because it may be
4959 -- the completion of a previous declaration. If it is not, the cross-
4960 -- reference entry will be emitted for the new subprogram declaration.
4962 if Nkind (Parent (N)) /= N_Expression_Function then
4963 Generate_Definition (Designator);
4966 if Nkind (N) = N_Function_Specification then
4967 Set_Ekind (Designator, E_Function);
4968 Set_Mechanism (Designator, Default_Mechanism);
4970 Set_Ekind (Designator, E_Procedure);
4971 Set_Etype (Designator, Standard_Void_Type);
4974 -- Flag Is_Inlined_Always is True by default, and reversed to False for
4975 -- those subprograms which could be inlined in GNATprove mode (because
4976 -- Body_To_Inline is non-Empty) but should not be inlined.
4978 if GNATprove_Mode then
4979 Set_Is_Inlined_Always (Designator);
4982 -- Introduce new scope for analysis of the formals and the return type
4984 Set_Scope (Designator, Current_Scope);
4986 if Present (Formals) then
4987 Push_Scope (Designator);
4988 Process_Formals (Formals, N);
4990 -- Check dimensions in N for formals with default expression
4992 Analyze_Dimension_Formals (N, Formals);
4994 -- Ada 2005 (AI-345): If this is an overriding operation of an
4995 -- inherited interface operation, and the controlling type is
4996 -- a synchronized type, replace the type with its corresponding
4997 -- record, to match the proper signature of an overriding operation.
4998 -- Same processing for an access parameter whose designated type is
4999 -- derived from a synchronized interface.
5001 -- This modification is not done for invariant procedures because
5002 -- the corresponding record may not necessarely be visible when the
5003 -- concurrent type acts as the full view of a private type.
5006 -- type Prot is private with Type_Invariant => ...;
5007 -- procedure ConcInvariant (Obj : Prot);
5009 -- protected type Prot is ...;
5010 -- type Concurrent_Record_Prot is record ...;
5011 -- procedure ConcInvariant (Obj : Prot) is
5013 -- end ConcInvariant;
5016 -- In the example above, both the spec and body of the invariant
5017 -- procedure must utilize the private type as the controlling type.
5019 if Ada_Version >= Ada_2005
5020 and then not Is_Invariant_Procedure_Or_Body (Designator)
5024 Formal_Typ : Entity_Id;
5025 Rec_Typ : Entity_Id;
5026 Desig_Typ : Entity_Id;
5029 Formal := First_Formal (Designator);
5030 while Present (Formal) loop
5031 Formal_Typ := Etype (Formal);
5033 if Is_Concurrent_Type (Formal_Typ)
5034 and then Present (Corresponding_Record_Type (Formal_Typ))
5036 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
5038 if Present (Interfaces (Rec_Typ)) then
5039 Set_Etype (Formal, Rec_Typ);
5042 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
5043 Desig_Typ := Designated_Type (Formal_Typ);
5045 if Is_Concurrent_Type (Desig_Typ)
5046 and then Present (Corresponding_Record_Type (Desig_Typ))
5048 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
5050 if Present (Interfaces (Rec_Typ)) then
5051 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
5056 Next_Formal (Formal);
5063 -- The subprogram scope is pushed and popped around the processing of
5064 -- the return type for consistency with call above to Process_Formals
5065 -- (which itself can call Analyze_Return_Type), and to ensure that any
5066 -- itype created for the return type will be associated with the proper
5069 elsif Nkind (N) = N_Function_Specification then
5070 Push_Scope (Designator);
5071 Analyze_Return_Type (N);
5077 if Nkind (N) = N_Function_Specification then
5079 -- Deal with operator symbol case
5081 if Nkind (Designator) = N_Defining_Operator_Symbol then
5082 Valid_Operator_Definition (Designator);
5085 May_Need_Actuals (Designator);
5087 -- Ada 2005 (AI-251): If the return type is abstract, verify that
5088 -- the subprogram is abstract also. This does not apply to renaming
5089 -- declarations, where abstractness is inherited, and to subprogram
5090 -- bodies generated for stream operations, which become renamings as
5093 -- In case of primitives associated with abstract interface types
5094 -- the check is applied later (see Analyze_Subprogram_Declaration).
5096 if not Nkind_In (Original_Node (Parent (N)),
5097 N_Abstract_Subprogram_Declaration,
5098 N_Formal_Abstract_Subprogram_Declaration,
5099 N_Subprogram_Renaming_Declaration)
5101 if Is_Abstract_Type (Etype (Designator))
5102 and then not Is_Interface (Etype (Designator))
5105 ("function that returns abstract type must be abstract", N);
5107 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
5108 -- access result whose designated type is abstract.
5110 elsif Ada_Version >= Ada_2012
5111 and then Nkind (Result_Definition (N)) = N_Access_Definition
5113 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
5114 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
5117 ("function whose access result designates abstract type "
5118 & "must be abstract", N);
5124 end Analyze_Subprogram_Specification;
5126 -----------------------
5127 -- Check_Conformance --
5128 -----------------------
5130 procedure Check_Conformance
5131 (New_Id : Entity_Id;
5133 Ctype : Conformance_Type;
5135 Conforms : out Boolean;
5136 Err_Loc : Node_Id := Empty;
5137 Get_Inst : Boolean := False;
5138 Skip_Controlling_Formals : Boolean := False)
5140 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5141 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5142 -- If Errmsg is True, then processing continues to post an error message
5143 -- for conformance error on given node. Two messages are output. The
5144 -- first message points to the previous declaration with a general "no
5145 -- conformance" message. The second is the detailed reason, supplied as
5146 -- Msg. The parameter N provide information for a possible & insertion
5147 -- in the message, and also provides the location for posting the
5148 -- message in the absence of a specified Err_Loc location.
5150 function Conventions_Match
5152 Id2 : Entity_Id) return Boolean;
5153 -- Determine whether the conventions of arbitrary entities Id1 and Id2
5156 -----------------------
5157 -- Conformance_Error --
5158 -----------------------
5160 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5167 if No (Err_Loc) then
5173 Error_Msg_Sloc := Sloc (Old_Id);
5176 when Type_Conformant =>
5177 Error_Msg_N -- CODEFIX
5178 ("not type conformant with declaration#!", Enode);
5180 when Mode_Conformant =>
5181 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5183 ("not mode conformant with operation inherited#!",
5187 ("not mode conformant with declaration#!", Enode);
5190 when Subtype_Conformant =>
5191 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5193 ("not subtype conformant with operation inherited#!",
5197 ("not subtype conformant with declaration#!", Enode);
5200 when Fully_Conformant =>
5201 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5202 Error_Msg_N -- CODEFIX
5203 ("not fully conformant with operation inherited#!",
5206 Error_Msg_N -- CODEFIX
5207 ("not fully conformant with declaration#!", Enode);
5211 Error_Msg_NE (Msg, Enode, N);
5213 end Conformance_Error;
5215 -----------------------
5216 -- Conventions_Match --
5217 -----------------------
5219 function Conventions_Match
5221 Id2 : Entity_Id) return Boolean
5224 -- Ignore the conventions of anonymous access-to-subprogram types
5225 -- and subprogram types because these are internally generated and
5226 -- the only way these may receive a convention is if they inherit
5227 -- the convention of a related subprogram.
5229 if Ekind_In (Id1, E_Anonymous_Access_Subprogram_Type,
5232 Ekind_In (Id2, E_Anonymous_Access_Subprogram_Type,
5237 -- Otherwise compare the conventions directly
5240 return Convention (Id1) = Convention (Id2);
5242 end Conventions_Match;
5246 Old_Type : constant Entity_Id := Etype (Old_Id);
5247 New_Type : constant Entity_Id := Etype (New_Id);
5248 Old_Formal : Entity_Id;
5249 New_Formal : Entity_Id;
5250 Access_Types_Match : Boolean;
5251 Old_Formal_Base : Entity_Id;
5252 New_Formal_Base : Entity_Id;
5254 -- Start of processing for Check_Conformance
5259 -- We need a special case for operators, since they don't appear
5262 if Ctype = Type_Conformant then
5263 if Ekind (New_Id) = E_Operator
5264 and then Operator_Matches_Spec (New_Id, Old_Id)
5270 -- If both are functions/operators, check return types conform
5272 if Old_Type /= Standard_Void_Type
5274 New_Type /= Standard_Void_Type
5276 -- If we are checking interface conformance we omit controlling
5277 -- arguments and result, because we are only checking the conformance
5278 -- of the remaining parameters.
5280 if Has_Controlling_Result (Old_Id)
5281 and then Has_Controlling_Result (New_Id)
5282 and then Skip_Controlling_Formals
5286 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5287 if Ctype >= Subtype_Conformant
5288 and then not Predicates_Match (Old_Type, New_Type)
5291 ("\predicate of return type does not match!", New_Id);
5294 ("\return type does not match!", New_Id);
5300 -- Ada 2005 (AI-231): In case of anonymous access types check the
5301 -- null-exclusion and access-to-constant attributes match.
5303 if Ada_Version >= Ada_2005
5304 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5306 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5307 or else Is_Access_Constant (Etype (Old_Type)) /=
5308 Is_Access_Constant (Etype (New_Type)))
5310 Conformance_Error ("\return type does not match!", New_Id);
5314 -- If either is a function/operator and the other isn't, error
5316 elsif Old_Type /= Standard_Void_Type
5317 or else New_Type /= Standard_Void_Type
5319 Conformance_Error ("\functions can only match functions!", New_Id);
5323 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5324 -- If this is a renaming as body, refine error message to indicate that
5325 -- the conflict is with the original declaration. If the entity is not
5326 -- frozen, the conventions don't have to match, the one of the renamed
5327 -- entity is inherited.
5329 if Ctype >= Subtype_Conformant then
5330 if not Conventions_Match (Old_Id, New_Id) then
5331 if not Is_Frozen (New_Id) then
5334 elsif Present (Err_Loc)
5335 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5336 and then Present (Corresponding_Spec (Err_Loc))
5338 Error_Msg_Name_1 := Chars (New_Id);
5340 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5341 Conformance_Error ("\prior declaration for% has convention %!");
5344 Conformance_Error ("\calling conventions do not match!");
5349 elsif Is_Formal_Subprogram (Old_Id)
5350 or else Is_Formal_Subprogram (New_Id)
5351 or else (Is_Subprogram (New_Id)
5352 and then Present (Alias (New_Id))
5353 and then Is_Formal_Subprogram (Alias (New_Id)))
5356 ("\formal subprograms are not subtype conformant "
5357 & "(RM 6.3.1 (17/3))");
5361 -- Deal with parameters
5363 -- Note: we use the entity information, rather than going directly
5364 -- to the specification in the tree. This is not only simpler, but
5365 -- absolutely necessary for some cases of conformance tests between
5366 -- operators, where the declaration tree simply does not exist.
5368 Old_Formal := First_Formal (Old_Id);
5369 New_Formal := First_Formal (New_Id);
5370 while Present (Old_Formal) and then Present (New_Formal) loop
5371 if Is_Controlling_Formal (Old_Formal)
5372 and then Is_Controlling_Formal (New_Formal)
5373 and then Skip_Controlling_Formals
5375 -- The controlling formals will have different types when
5376 -- comparing an interface operation with its match, but both
5377 -- or neither must be access parameters.
5379 if Is_Access_Type (Etype (Old_Formal))
5381 Is_Access_Type (Etype (New_Formal))
5383 goto Skip_Controlling_Formal;
5386 ("\access parameter does not match!", New_Formal);
5390 -- Ada 2012: Mode conformance also requires that formal parameters
5391 -- be both aliased, or neither.
5393 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5394 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5396 ("\aliased parameter mismatch!", New_Formal);
5400 if Ctype = Fully_Conformant then
5402 -- Names must match. Error message is more accurate if we do
5403 -- this before checking that the types of the formals match.
5405 if Chars (Old_Formal) /= Chars (New_Formal) then
5406 Conformance_Error ("\name& does not match!", New_Formal);
5408 -- Set error posted flag on new formal as well to stop
5409 -- junk cascaded messages in some cases.
5411 Set_Error_Posted (New_Formal);
5415 -- Null exclusion must match
5417 if Null_Exclusion_Present (Parent (Old_Formal))
5419 Null_Exclusion_Present (Parent (New_Formal))
5421 -- Only give error if both come from source. This should be
5422 -- investigated some time, since it should not be needed ???
5424 if Comes_From_Source (Old_Formal)
5426 Comes_From_Source (New_Formal)
5429 ("\null exclusion for& does not match", New_Formal);
5431 -- Mark error posted on the new formal to avoid duplicated
5432 -- complaint about types not matching.
5434 Set_Error_Posted (New_Formal);
5439 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
5440 -- case occurs whenever a subprogram is being renamed and one of its
5441 -- parameters imposes a null exclusion. For example:
5443 -- type T is null record;
5444 -- type Acc_T is access T;
5445 -- subtype Acc_T_Sub is Acc_T;
5447 -- procedure P (Obj : not null Acc_T_Sub); -- itype
5448 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
5451 Old_Formal_Base := Etype (Old_Formal);
5452 New_Formal_Base := Etype (New_Formal);
5455 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
5456 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
5459 Access_Types_Match := Ada_Version >= Ada_2005
5461 -- Ensure that this rule is only applied when New_Id is a
5462 -- renaming of Old_Id.
5464 and then Nkind (Parent (Parent (New_Id))) =
5465 N_Subprogram_Renaming_Declaration
5466 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
5467 and then Present (Entity (Name (Parent (Parent (New_Id)))))
5468 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
5470 -- Now handle the allowed access-type case
5472 and then Is_Access_Type (Old_Formal_Base)
5473 and then Is_Access_Type (New_Formal_Base)
5475 -- The type kinds must match. The only exception occurs with
5476 -- multiple generics of the form:
5479 -- type F is private; type A is private;
5480 -- type F_Ptr is access F; type A_Ptr is access A;
5481 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
5482 -- package F_Pack is ... package A_Pack is
5483 -- package F_Inst is
5484 -- new F_Pack (A, A_Ptr, A_P);
5486 -- When checking for conformance between the parameters of A_P
5487 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
5488 -- because the compiler has transformed A_Ptr into a subtype of
5489 -- F_Ptr. We catch this case in the code below.
5491 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
5493 (Is_Generic_Type (Old_Formal_Base)
5494 and then Is_Generic_Type (New_Formal_Base)
5495 and then Is_Internal (New_Formal_Base)
5496 and then Etype (Etype (New_Formal_Base)) =
5498 and then Directly_Designated_Type (Old_Formal_Base) =
5499 Directly_Designated_Type (New_Formal_Base)
5500 and then ((Is_Itype (Old_Formal_Base)
5501 and then Can_Never_Be_Null (Old_Formal_Base))
5503 (Is_Itype (New_Formal_Base)
5504 and then Can_Never_Be_Null (New_Formal_Base)));
5506 -- Types must always match. In the visible part of an instance,
5507 -- usual overloading rules for dispatching operations apply, and
5508 -- we check base types (not the actual subtypes).
5510 if In_Instance_Visible_Part
5511 and then Is_Dispatching_Operation (New_Id)
5513 if not Conforming_Types
5514 (T1 => Base_Type (Etype (Old_Formal)),
5515 T2 => Base_Type (Etype (New_Formal)),
5517 Get_Inst => Get_Inst)
5518 and then not Access_Types_Match
5520 Conformance_Error ("\type of & does not match!", New_Formal);
5524 elsif not Conforming_Types
5525 (T1 => Old_Formal_Base,
5526 T2 => New_Formal_Base,
5528 Get_Inst => Get_Inst)
5529 and then not Access_Types_Match
5531 -- Don't give error message if old type is Any_Type. This test
5532 -- avoids some cascaded errors, e.g. in case of a bad spec.
5534 if Errmsg and then Old_Formal_Base = Any_Type then
5537 if Ctype >= Subtype_Conformant
5539 not Predicates_Match (Old_Formal_Base, New_Formal_Base)
5542 ("\predicate of & does not match!", New_Formal);
5545 ("\type of & does not match!", New_Formal);
5547 if not Dimensions_Match (Old_Formal_Base, New_Formal_Base)
5549 Error_Msg_N ("\dimensions mismatch!", New_Formal);
5557 -- For mode conformance, mode must match
5559 if Ctype >= Mode_Conformant then
5560 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
5561 if not Ekind_In (New_Id, E_Function, E_Procedure)
5562 or else not Is_Primitive_Wrapper (New_Id)
5564 Conformance_Error ("\mode of & does not match!", New_Formal);
5568 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
5570 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
5572 Error_Msg_PT (New_Id, Ultimate_Alias (Old_Id));
5575 ("\mode of & does not match!", New_Formal);
5582 -- Part of mode conformance for access types is having the same
5583 -- constant modifier.
5585 elsif Access_Types_Match
5586 and then Is_Access_Constant (Old_Formal_Base) /=
5587 Is_Access_Constant (New_Formal_Base)
5590 ("\constant modifier does not match!", New_Formal);
5595 if Ctype >= Subtype_Conformant then
5597 -- Ada 2005 (AI-231): In case of anonymous access types check
5598 -- the null-exclusion and access-to-constant attributes must
5599 -- match. For null exclusion, we test the types rather than the
5600 -- formals themselves, since the attribute is only set reliably
5601 -- on the formals in the Ada 95 case, and we exclude the case
5602 -- where Old_Formal is marked as controlling, to avoid errors
5603 -- when matching completing bodies with dispatching declarations
5604 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
5606 if Ada_Version >= Ada_2005
5607 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
5608 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
5610 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
5611 Can_Never_Be_Null (Etype (New_Formal))
5613 not Is_Controlling_Formal (Old_Formal))
5615 Is_Access_Constant (Etype (Old_Formal)) /=
5616 Is_Access_Constant (Etype (New_Formal)))
5618 -- Do not complain if error already posted on New_Formal. This
5619 -- avoids some redundant error messages.
5621 and then not Error_Posted (New_Formal)
5623 -- It is allowed to omit the null-exclusion in case of stream
5624 -- attribute subprograms. We recognize stream subprograms
5625 -- through their TSS-generated suffix.
5628 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
5631 if TSS_Name /= TSS_Stream_Read
5632 and then TSS_Name /= TSS_Stream_Write
5633 and then TSS_Name /= TSS_Stream_Input
5634 and then TSS_Name /= TSS_Stream_Output
5636 -- Here we have a definite conformance error. It is worth
5637 -- special casing the error message for the case of a
5638 -- controlling formal (which excludes null).
5640 if Is_Controlling_Formal (New_Formal) then
5641 Error_Msg_Node_2 := Scope (New_Formal);
5643 ("\controlling formal & of & excludes null, "
5644 & "declaration must exclude null as well",
5647 -- Normal case (couldn't we give more detail here???)
5651 ("\type of & does not match!", New_Formal);
5660 -- Full conformance checks
5662 if Ctype = Fully_Conformant then
5664 -- We have checked already that names match
5666 if Parameter_Mode (Old_Formal) = E_In_Parameter then
5668 -- Check default expressions for in parameters
5671 NewD : constant Boolean :=
5672 Present (Default_Value (New_Formal));
5673 OldD : constant Boolean :=
5674 Present (Default_Value (Old_Formal));
5676 if NewD or OldD then
5678 -- The old default value has been analyzed because the
5679 -- current full declaration will have frozen everything
5680 -- before. The new default value has not been analyzed,
5681 -- so analyze it now before we check for conformance.
5684 Push_Scope (New_Id);
5685 Preanalyze_Spec_Expression
5686 (Default_Value (New_Formal), Etype (New_Formal));
5690 if not (NewD and OldD)
5691 or else not Fully_Conformant_Expressions
5692 (Default_Value (Old_Formal),
5693 Default_Value (New_Formal))
5696 ("\default expression for & does not match!",
5705 -- A couple of special checks for Ada 83 mode. These checks are
5706 -- skipped if either entity is an operator in package Standard,
5707 -- or if either old or new instance is not from the source program.
5709 if Ada_Version = Ada_83
5710 and then Sloc (Old_Id) > Standard_Location
5711 and then Sloc (New_Id) > Standard_Location
5712 and then Comes_From_Source (Old_Id)
5713 and then Comes_From_Source (New_Id)
5716 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
5717 New_Param : constant Node_Id := Declaration_Node (New_Formal);
5720 -- Explicit IN must be present or absent in both cases. This
5721 -- test is required only in the full conformance case.
5723 if In_Present (Old_Param) /= In_Present (New_Param)
5724 and then Ctype = Fully_Conformant
5727 ("\(Ada 83) IN must appear in both declarations",
5732 -- Grouping (use of comma in param lists) must be the same
5733 -- This is where we catch a misconformance like:
5736 -- A : Integer; B : Integer
5738 -- which are represented identically in the tree except
5739 -- for the setting of the flags More_Ids and Prev_Ids.
5741 if More_Ids (Old_Param) /= More_Ids (New_Param)
5742 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
5745 ("\grouping of & does not match!", New_Formal);
5751 -- This label is required when skipping controlling formals
5753 <<Skip_Controlling_Formal>>
5755 Next_Formal (Old_Formal);
5756 Next_Formal (New_Formal);
5759 if Present (Old_Formal) then
5760 Conformance_Error ("\too few parameters!");
5763 elsif Present (New_Formal) then
5764 Conformance_Error ("\too many parameters!", New_Formal);
5767 end Check_Conformance;
5769 -----------------------
5770 -- Check_Conventions --
5771 -----------------------
5773 procedure Check_Conventions (Typ : Entity_Id) is
5774 Ifaces_List : Elist_Id;
5776 procedure Check_Convention (Op : Entity_Id);
5777 -- Verify that the convention of inherited dispatching operation Op is
5778 -- consistent among all subprograms it overrides. In order to minimize
5779 -- the search, Search_From is utilized to designate a specific point in
5780 -- the list rather than iterating over the whole list once more.
5782 ----------------------
5783 -- Check_Convention --
5784 ----------------------
5786 procedure Check_Convention (Op : Entity_Id) is
5787 Op_Conv : constant Convention_Id := Convention (Op);
5788 Iface_Conv : Convention_Id;
5789 Iface_Elmt : Elmt_Id;
5790 Iface_Prim_Elmt : Elmt_Id;
5791 Iface_Prim : Entity_Id;
5794 Iface_Elmt := First_Elmt (Ifaces_List);
5795 while Present (Iface_Elmt) loop
5797 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
5798 while Present (Iface_Prim_Elmt) loop
5799 Iface_Prim := Node (Iface_Prim_Elmt);
5800 Iface_Conv := Convention (Iface_Prim);
5802 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
5803 and then Iface_Conv /= Op_Conv
5806 ("inconsistent conventions in primitive operations", Typ);
5808 Error_Msg_Name_1 := Chars (Op);
5809 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
5810 Error_Msg_Sloc := Sloc (Op);
5812 if Comes_From_Source (Op) or else No (Alias (Op)) then
5813 if not Present (Overridden_Operation (Op)) then
5814 Error_Msg_N ("\\primitive % defined #", Typ);
5817 ("\\overriding operation % with "
5818 & "convention % defined #", Typ);
5821 else pragma Assert (Present (Alias (Op)));
5822 Error_Msg_Sloc := Sloc (Alias (Op));
5823 Error_Msg_N ("\\inherited operation % with "
5824 & "convention % defined #", Typ);
5827 Error_Msg_Name_1 := Chars (Op);
5828 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
5829 Error_Msg_Sloc := Sloc (Iface_Prim);
5830 Error_Msg_N ("\\overridden operation % with "
5831 & "convention % defined #", Typ);
5833 -- Avoid cascading errors
5838 Next_Elmt (Iface_Prim_Elmt);
5841 Next_Elmt (Iface_Elmt);
5843 end Check_Convention;
5847 Prim_Op : Entity_Id;
5848 Prim_Op_Elmt : Elmt_Id;
5850 -- Start of processing for Check_Conventions
5853 if not Has_Interfaces (Typ) then
5857 Collect_Interfaces (Typ, Ifaces_List);
5859 -- The algorithm checks every overriding dispatching operation against
5860 -- all the corresponding overridden dispatching operations, detecting
5861 -- differences in conventions.
5863 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
5864 while Present (Prim_Op_Elmt) loop
5865 Prim_Op := Node (Prim_Op_Elmt);
5867 -- A small optimization: skip the predefined dispatching operations
5868 -- since they always have the same convention.
5870 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
5871 Check_Convention (Prim_Op);
5874 Next_Elmt (Prim_Op_Elmt);
5876 end Check_Conventions;
5878 ------------------------------
5879 -- Check_Delayed_Subprogram --
5880 ------------------------------
5882 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
5883 procedure Possible_Freeze (T : Entity_Id);
5884 -- T is the type of either a formal parameter or of the return type. If
5885 -- T is not yet frozen and needs a delayed freeze, then the subprogram
5886 -- itself must be delayed.
5888 ---------------------
5889 -- Possible_Freeze --
5890 ---------------------
5892 procedure Possible_Freeze (T : Entity_Id) is
5893 Scop : constant Entity_Id := Scope (Designator);
5896 -- If the subprogram appears within a package instance (which may be
5897 -- the wrapper package of a subprogram instance) the freeze node for
5898 -- that package will freeze the subprogram at the proper place, so
5899 -- do not emit a freeze node for the subprogram, given that it may
5900 -- appear in the wrong scope.
5902 if Ekind (Scop) = E_Package
5903 and then not Comes_From_Source (Scop)
5904 and then Is_Generic_Instance (Scop)
5908 elsif Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
5909 Set_Has_Delayed_Freeze (Designator);
5911 elsif Is_Access_Type (T)
5912 and then Has_Delayed_Freeze (Designated_Type (T))
5913 and then not Is_Frozen (Designated_Type (T))
5915 Set_Has_Delayed_Freeze (Designator);
5917 end Possible_Freeze;
5923 -- Start of processing for Check_Delayed_Subprogram
5926 -- All subprograms, including abstract subprograms, may need a freeze
5927 -- node if some formal type or the return type needs one.
5929 Possible_Freeze (Etype (Designator));
5930 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
5932 -- Need delayed freeze if any of the formal types themselves need a
5933 -- delayed freeze and are not yet frozen.
5935 F := First_Formal (Designator);
5936 while Present (F) loop
5937 Possible_Freeze (Etype (F));
5938 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
5942 -- Mark functions that return by reference. Note that it cannot be done
5943 -- for delayed_freeze subprograms because the underlying returned type
5944 -- may not be known yet (for private types).
5946 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
5948 Typ : constant Entity_Id := Etype (Designator);
5949 Utyp : constant Entity_Id := Underlying_Type (Typ);
5952 if Is_Limited_View (Typ) then
5953 Set_Returns_By_Ref (Designator);
5955 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
5956 Set_Returns_By_Ref (Designator);
5960 end Check_Delayed_Subprogram;
5962 ------------------------------------
5963 -- Check_Discriminant_Conformance --
5964 ------------------------------------
5966 procedure Check_Discriminant_Conformance
5971 Old_Discr : Entity_Id := First_Discriminant (Prev);
5972 New_Discr : Node_Id := First (Discriminant_Specifications (N));
5973 New_Discr_Id : Entity_Id;
5974 New_Discr_Type : Entity_Id;
5976 procedure Conformance_Error (Msg : String; N : Node_Id);
5977 -- Post error message for conformance error on given node. Two messages
5978 -- are output. The first points to the previous declaration with a
5979 -- general "no conformance" message. The second is the detailed reason,
5980 -- supplied as Msg. The parameter N provide information for a possible
5981 -- & insertion in the message.
5983 -----------------------
5984 -- Conformance_Error --
5985 -----------------------
5987 procedure Conformance_Error (Msg : String; N : Node_Id) is
5989 Error_Msg_Sloc := Sloc (Prev_Loc);
5990 Error_Msg_N -- CODEFIX
5991 ("not fully conformant with declaration#!", N);
5992 Error_Msg_NE (Msg, N, N);
5993 end Conformance_Error;
5995 -- Start of processing for Check_Discriminant_Conformance
5998 while Present (Old_Discr) and then Present (New_Discr) loop
5999 New_Discr_Id := Defining_Identifier (New_Discr);
6001 -- The subtype mark of the discriminant on the full type has not
6002 -- been analyzed so we do it here. For an access discriminant a new
6005 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
6007 Access_Definition (N, Discriminant_Type (New_Discr));
6010 Analyze (Discriminant_Type (New_Discr));
6011 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6013 -- Ada 2005: if the discriminant definition carries a null
6014 -- exclusion, create an itype to check properly for consistency
6015 -- with partial declaration.
6017 if Is_Access_Type (New_Discr_Type)
6018 and then Null_Exclusion_Present (New_Discr)
6021 Create_Null_Excluding_Itype
6022 (T => New_Discr_Type,
6023 Related_Nod => New_Discr,
6024 Scope_Id => Current_Scope);
6028 if not Conforming_Types
6029 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6031 Conformance_Error ("type of & does not match!", New_Discr_Id);
6034 -- Treat the new discriminant as an occurrence of the old one,
6035 -- for navigation purposes, and fill in some semantic
6036 -- information, for completeness.
6038 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6039 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6040 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6045 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6046 Conformance_Error ("name & does not match!", New_Discr_Id);
6050 -- Default expressions must match
6053 NewD : constant Boolean :=
6054 Present (Expression (New_Discr));
6055 OldD : constant Boolean :=
6056 Present (Expression (Parent (Old_Discr)));
6059 if NewD or OldD then
6061 -- The old default value has been analyzed and expanded,
6062 -- because the current full declaration will have frozen
6063 -- everything before. The new default values have not been
6064 -- expanded, so expand now to check conformance.
6067 Preanalyze_Spec_Expression
6068 (Expression (New_Discr), New_Discr_Type);
6071 if not (NewD and OldD)
6072 or else not Fully_Conformant_Expressions
6073 (Expression (Parent (Old_Discr)),
6074 Expression (New_Discr))
6078 ("default expression for & does not match!",
6085 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6087 if Ada_Version = Ada_83 then
6089 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6092 -- Grouping (use of comma in param lists) must be the same
6093 -- This is where we catch a misconformance like:
6096 -- A : Integer; B : Integer
6098 -- which are represented identically in the tree except
6099 -- for the setting of the flags More_Ids and Prev_Ids.
6101 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6102 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6105 ("grouping of & does not match!", New_Discr_Id);
6111 Next_Discriminant (Old_Discr);
6115 if Present (Old_Discr) then
6116 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6119 elsif Present (New_Discr) then
6121 ("too many discriminants!", Defining_Identifier (New_Discr));
6124 end Check_Discriminant_Conformance;
6126 ----------------------------
6127 -- Check_Fully_Conformant --
6128 ----------------------------
6130 procedure Check_Fully_Conformant
6131 (New_Id : Entity_Id;
6133 Err_Loc : Node_Id := Empty)
6136 pragma Warnings (Off, Result);
6139 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6140 end Check_Fully_Conformant;
6142 --------------------------
6143 -- Check_Limited_Return --
6144 --------------------------
6146 procedure Check_Limited_Return
6152 -- Ada 2005 (AI-318-02): Return-by-reference types have been removed and
6153 -- replaced by anonymous access results. This is an incompatibility with
6154 -- Ada 95. Not clear whether this should be enforced yet or perhaps
6155 -- controllable with special switch. ???
6157 -- A limited interface that is not immutably limited is OK
6159 if Is_Limited_Interface (R_Type)
6161 not (Is_Task_Interface (R_Type)
6162 or else Is_Protected_Interface (R_Type)
6163 or else Is_Synchronized_Interface (R_Type))
6167 elsif Is_Limited_Type (R_Type)
6168 and then not Is_Interface (R_Type)
6169 and then Comes_From_Source (N)
6170 and then not In_Instance_Body
6171 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
6173 -- Error in Ada 2005
6175 if Ada_Version >= Ada_2005
6176 and then not Debug_Flag_Dot_L
6177 and then not GNAT_Mode
6180 ("(Ada 2005) cannot copy object of a limited type "
6181 & "(RM-2005 6.5(5.5/2))", Expr);
6183 if Is_Limited_View (R_Type) then
6185 ("\return by reference not permitted in Ada 2005", Expr);
6188 -- Warn in Ada 95 mode, to give folks a heads up about this
6191 -- In GNAT mode, this is just a warning, to allow it to be evilly
6192 -- turned off. Otherwise it is a real error.
6194 -- In a generic context, simplify the warning because it makes no
6195 -- sense to discuss pass-by-reference or copy.
6197 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
6198 if Inside_A_Generic then
6200 ("return of limited object not permitted in Ada 2005 "
6201 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6203 elsif Is_Limited_View (R_Type) then
6205 ("return by reference not permitted in Ada 2005 "
6206 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6209 ("cannot copy object of a limited type in Ada 2005 "
6210 & "(RM-2005 6.5(5.5/2))?y?", Expr);
6213 -- Ada 95 mode, and compatibility warnings disabled
6216 pragma Assert (Ada_Version <= Ada_95);
6217 pragma Assert (not (Warn_On_Ada_2005_Compatibility or GNAT_Mode));
6218 return; -- skip continuation messages below
6221 if not Inside_A_Generic then
6223 ("\consider switching to return of access type", Expr);
6224 Explain_Limited_Type (R_Type, Expr);
6227 end Check_Limited_Return;
6229 ---------------------------
6230 -- Check_Mode_Conformant --
6231 ---------------------------
6233 procedure Check_Mode_Conformant
6234 (New_Id : Entity_Id;
6236 Err_Loc : Node_Id := Empty;
6237 Get_Inst : Boolean := False)
6240 pragma Warnings (Off, Result);
6243 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6244 end Check_Mode_Conformant;
6246 --------------------------------
6247 -- Check_Overriding_Indicator --
6248 --------------------------------
6250 procedure Check_Overriding_Indicator
6252 Overridden_Subp : Entity_Id;
6253 Is_Primitive : Boolean)
6259 -- No overriding indicator for literals
6261 if Ekind (Subp) = E_Enumeration_Literal then
6264 elsif Ekind (Subp) = E_Entry then
6265 Decl := Parent (Subp);
6267 -- No point in analyzing a malformed operator
6269 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6270 and then Error_Posted (Subp)
6275 Decl := Unit_Declaration_Node (Subp);
6278 if Nkind_In (Decl, N_Subprogram_Body,
6279 N_Subprogram_Body_Stub,
6280 N_Subprogram_Declaration,
6281 N_Abstract_Subprogram_Declaration,
6282 N_Subprogram_Renaming_Declaration)
6284 Spec := Specification (Decl);
6286 elsif Nkind (Decl) = N_Entry_Declaration then
6293 -- The overriding operation is type conformant with the overridden one,
6294 -- but the names of the formals are not required to match. If the names
6295 -- appear permuted in the overriding operation, this is a possible
6296 -- source of confusion that is worth diagnosing. Controlling formals
6297 -- often carry names that reflect the type, and it is not worthwhile
6298 -- requiring that their names match.
6300 if Present (Overridden_Subp)
6301 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6308 Form1 := First_Formal (Subp);
6309 Form2 := First_Formal (Overridden_Subp);
6311 -- If the overriding operation is a synchronized operation, skip
6312 -- the first parameter of the overridden operation, which is
6313 -- implicit in the new one. If the operation is declared in the
6314 -- body it is not primitive and all formals must match.
6316 if Is_Concurrent_Type (Scope (Subp))
6317 and then Is_Tagged_Type (Scope (Subp))
6318 and then not Has_Completion (Scope (Subp))
6320 Form2 := Next_Formal (Form2);
6323 if Present (Form1) then
6324 Form1 := Next_Formal (Form1);
6325 Form2 := Next_Formal (Form2);
6328 while Present (Form1) loop
6329 if not Is_Controlling_Formal (Form1)
6330 and then Present (Next_Formal (Form2))
6331 and then Chars (Form1) = Chars (Next_Formal (Form2))
6333 Error_Msg_Node_2 := Alias (Overridden_Subp);
6334 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6336 ("& does not match corresponding formal of&#",
6341 Next_Formal (Form1);
6342 Next_Formal (Form2);
6347 -- If there is an overridden subprogram, then check that there is no
6348 -- "not overriding" indicator, and mark the subprogram as overriding.
6349 -- This is not done if the overridden subprogram is marked as hidden,
6350 -- which can occur for the case of inherited controlled operations
6351 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6352 -- subprogram is not itself hidden. (Note: This condition could probably
6353 -- be simplified, leaving out the testing for the specific controlled
6354 -- cases, but it seems safer and clearer this way, and echoes similar
6355 -- special-case tests of this kind in other places.)
6357 if Present (Overridden_Subp)
6358 and then (not Is_Hidden (Overridden_Subp)
6360 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6363 and then Present (Alias (Overridden_Subp))
6364 and then not Is_Hidden (Alias (Overridden_Subp))))
6366 if Must_Not_Override (Spec) then
6367 Error_Msg_Sloc := Sloc (Overridden_Subp);
6369 if Ekind (Subp) = E_Entry then
6371 ("entry & overrides inherited operation #", Spec, Subp);
6374 ("subprogram & overrides inherited operation #", Spec, Subp);
6377 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6378 -- as an extension of Root_Controlled, and thus has a useless Adjust
6379 -- operation. This operation should not be inherited by other limited
6380 -- controlled types. An explicit Adjust for them is not overriding.
6382 elsif Must_Override (Spec)
6383 and then Chars (Overridden_Subp) = Name_Adjust
6384 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6385 and then Present (Alias (Overridden_Subp))
6386 and then In_Predefined_Unit (Alias (Overridden_Subp))
6389 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))));
6390 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6392 elsif Is_Subprogram (Subp) then
6393 if Is_Init_Proc (Subp) then
6396 elsif No (Overridden_Operation (Subp)) then
6398 -- For entities generated by Derive_Subprograms the overridden
6399 -- operation is the inherited primitive (which is available
6400 -- through the attribute alias)
6402 if (Is_Dispatching_Operation (Subp)
6403 or else Is_Dispatching_Operation (Overridden_Subp))
6404 and then not Comes_From_Source (Overridden_Subp)
6405 and then Find_Dispatching_Type (Overridden_Subp) =
6406 Find_Dispatching_Type (Subp)
6407 and then Present (Alias (Overridden_Subp))
6408 and then Comes_From_Source (Alias (Overridden_Subp))
6410 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6411 Inherit_Subprogram_Contract (Subp, Alias (Overridden_Subp));
6414 Set_Overridden_Operation (Subp, Overridden_Subp);
6415 Inherit_Subprogram_Contract (Subp, Overridden_Subp);
6420 -- If primitive flag is set or this is a protected operation, then
6421 -- the operation is overriding at the point of its declaration, so
6422 -- warn if necessary. Otherwise it may have been declared before the
6423 -- operation it overrides and no check is required.
6426 and then not Must_Override (Spec)
6427 and then (Is_Primitive
6428 or else Ekind (Scope (Subp)) = E_Protected_Type)
6430 Style.Missing_Overriding (Decl, Subp);
6433 -- If Subp is an operator, it may override a predefined operation, if
6434 -- it is defined in the same scope as the type to which it applies.
6435 -- In that case Overridden_Subp is empty because of our implicit
6436 -- representation for predefined operators. We have to check whether the
6437 -- signature of Subp matches that of a predefined operator. Note that
6438 -- first argument provides the name of the operator, and the second
6439 -- argument the signature that may match that of a standard operation.
6440 -- If the indicator is overriding, then the operator must match a
6441 -- predefined signature, because we know already that there is no
6442 -- explicit overridden operation.
6444 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6445 if Must_Not_Override (Spec) then
6447 -- If this is not a primitive or a protected subprogram, then
6448 -- "not overriding" is illegal.
6451 and then Ekind (Scope (Subp)) /= E_Protected_Type
6453 Error_Msg_N ("overriding indicator only allowed "
6454 & "if subprogram is primitive", Subp);
6456 elsif Can_Override_Operator (Subp) then
6458 ("subprogram& overrides predefined operator ", Spec, Subp);
6461 elsif Must_Override (Spec) then
6462 if No (Overridden_Operation (Subp))
6463 and then not Can_Override_Operator (Subp)
6465 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6468 elsif not Error_Posted (Subp)
6469 and then Style_Check
6470 and then Can_Override_Operator (Subp)
6471 and then not In_Predefined_Unit (Subp)
6473 -- If style checks are enabled, indicate that the indicator is
6474 -- missing. However, at the point of declaration, the type of
6475 -- which this is a primitive operation may be private, in which
6476 -- case the indicator would be premature.
6478 if Has_Private_Declaration (Etype (Subp))
6479 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6483 Style.Missing_Overriding (Decl, Subp);
6487 elsif Must_Override (Spec) then
6488 if Ekind (Subp) = E_Entry then
6489 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
6491 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6494 -- If the operation is marked "not overriding" and it's not primitive
6495 -- then an error is issued, unless this is an operation of a task or
6496 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
6497 -- has been specified have already been checked above.
6499 elsif Must_Not_Override (Spec)
6500 and then not Is_Primitive
6501 and then Ekind (Subp) /= E_Entry
6502 and then Ekind (Scope (Subp)) /= E_Protected_Type
6505 ("overriding indicator only allowed if subprogram is primitive",
6509 end Check_Overriding_Indicator;
6515 -- Note: this procedure needs to know far too much about how the expander
6516 -- messes with exceptions. The use of the flag Exception_Junk and the
6517 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
6518 -- works, but is not very clean. It would be better if the expansion
6519 -- routines would leave Original_Node working nicely, and we could use
6520 -- Original_Node here to ignore all the peculiar expander messing ???
6522 procedure Check_Returns
6526 Proc : Entity_Id := Empty)
6530 procedure Check_Statement_Sequence (L : List_Id);
6531 -- Internal recursive procedure to check a list of statements for proper
6532 -- termination by a return statement (or a transfer of control or a
6533 -- compound statement that is itself internally properly terminated).
6535 ------------------------------
6536 -- Check_Statement_Sequence --
6537 ------------------------------
6539 procedure Check_Statement_Sequence (L : List_Id) is
6544 function Assert_False return Boolean;
6545 -- Returns True if Last_Stm is a pragma Assert (False) that has been
6546 -- rewritten as a null statement when assertions are off. The assert
6547 -- is not active, but it is still enough to kill the warning.
6553 function Assert_False return Boolean is
6554 Orig : constant Node_Id := Original_Node (Last_Stm);
6557 if Nkind (Orig) = N_Pragma
6558 and then Pragma_Name (Orig) = Name_Assert
6559 and then not Error_Posted (Orig)
6562 Arg : constant Node_Id :=
6563 First (Pragma_Argument_Associations (Orig));
6564 Exp : constant Node_Id := Expression (Arg);
6566 return Nkind (Exp) = N_Identifier
6567 and then Chars (Exp) = Name_False;
6577 Raise_Exception_Call : Boolean;
6578 -- Set True if statement sequence terminated by Raise_Exception call
6579 -- or a Reraise_Occurrence call.
6581 -- Start of processing for Check_Statement_Sequence
6584 Raise_Exception_Call := False;
6586 -- Get last real statement
6588 Last_Stm := Last (L);
6590 -- Deal with digging out exception handler statement sequences that
6591 -- have been transformed by the local raise to goto optimization.
6592 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
6593 -- optimization has occurred, we are looking at something like:
6596 -- original stmts in block
6600 -- goto L1; | omitted if No_Exception_Propagation
6605 -- goto L3; -- skip handler when exception not raised
6607 -- <<L1>> -- target label for local exception
6621 -- and what we have to do is to dig out the estmts1 and estmts2
6622 -- sequences (which were the original sequences of statements in
6623 -- the exception handlers) and check them.
6625 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
6630 exit when Nkind (Stm) /= N_Block_Statement;
6631 exit when not Exception_Junk (Stm);
6634 exit when Nkind (Stm) /= N_Label;
6635 exit when not Exception_Junk (Stm);
6636 Check_Statement_Sequence
6637 (Statements (Handled_Statement_Sequence (Next (Stm))));
6642 exit when Nkind (Stm) /= N_Goto_Statement;
6643 exit when not Exception_Junk (Stm);
6647 -- Don't count pragmas
6649 while Nkind (Last_Stm) = N_Pragma
6651 -- Don't count call to SS_Release (can happen after Raise_Exception)
6654 (Nkind (Last_Stm) = N_Procedure_Call_Statement
6656 Nkind (Name (Last_Stm)) = N_Identifier
6658 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
6660 -- Don't count exception junk
6663 (Nkind_In (Last_Stm, N_Goto_Statement,
6665 N_Object_Declaration)
6666 and then Exception_Junk (Last_Stm))
6667 or else Nkind (Last_Stm) in N_Push_xxx_Label
6668 or else Nkind (Last_Stm) in N_Pop_xxx_Label
6670 -- Inserted code, such as finalization calls, is irrelevant: we only
6671 -- need to check original source.
6673 or else Is_Rewrite_Insertion (Last_Stm)
6678 -- Here we have the "real" last statement
6680 Kind := Nkind (Last_Stm);
6682 -- Transfer of control, OK. Note that in the No_Return procedure
6683 -- case, we already diagnosed any explicit return statements, so
6684 -- we can treat them as OK in this context.
6686 if Is_Transfer (Last_Stm) then
6689 -- Check cases of explicit non-indirect procedure calls
6691 elsif Kind = N_Procedure_Call_Statement
6692 and then Is_Entity_Name (Name (Last_Stm))
6694 -- Check call to Raise_Exception procedure which is treated
6695 -- specially, as is a call to Reraise_Occurrence.
6697 -- We suppress the warning in these cases since it is likely that
6698 -- the programmer really does not expect to deal with the case
6699 -- of Null_Occurrence, and thus would find a warning about a
6700 -- missing return curious, and raising Program_Error does not
6701 -- seem such a bad behavior if this does occur.
6703 -- Note that in the Ada 2005 case for Raise_Exception, the actual
6704 -- behavior will be to raise Constraint_Error (see AI-329).
6706 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
6708 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
6710 Raise_Exception_Call := True;
6712 -- For Raise_Exception call, test first argument, if it is
6713 -- an attribute reference for a 'Identity call, then we know
6714 -- that the call cannot possibly return.
6717 Arg : constant Node_Id :=
6718 Original_Node (First_Actual (Last_Stm));
6720 if Nkind (Arg) = N_Attribute_Reference
6721 and then Attribute_Name (Arg) = Name_Identity
6728 -- If statement, need to look inside if there is an else and check
6729 -- each constituent statement sequence for proper termination.
6731 elsif Kind = N_If_Statement
6732 and then Present (Else_Statements (Last_Stm))
6734 Check_Statement_Sequence (Then_Statements (Last_Stm));
6735 Check_Statement_Sequence (Else_Statements (Last_Stm));
6737 if Present (Elsif_Parts (Last_Stm)) then
6739 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
6742 while Present (Elsif_Part) loop
6743 Check_Statement_Sequence (Then_Statements (Elsif_Part));
6751 -- Case statement, check each case for proper termination
6753 elsif Kind = N_Case_Statement then
6757 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
6758 while Present (Case_Alt) loop
6759 Check_Statement_Sequence (Statements (Case_Alt));
6760 Next_Non_Pragma (Case_Alt);
6766 -- Block statement, check its handled sequence of statements
6768 elsif Kind = N_Block_Statement then
6774 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
6783 -- Loop statement. If there is an iteration scheme, we can definitely
6784 -- fall out of the loop. Similarly if there is an exit statement, we
6785 -- can fall out. In either case we need a following return.
6787 elsif Kind = N_Loop_Statement then
6788 if Present (Iteration_Scheme (Last_Stm))
6789 or else Has_Exit (Entity (Identifier (Last_Stm)))
6793 -- A loop with no exit statement or iteration scheme is either
6794 -- an infinite loop, or it has some other exit (raise/return).
6795 -- In either case, no warning is required.
6801 -- Timed entry call, check entry call and delay alternatives
6803 -- Note: in expanded code, the timed entry call has been converted
6804 -- to a set of expanded statements on which the check will work
6805 -- correctly in any case.
6807 elsif Kind = N_Timed_Entry_Call then
6809 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6810 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
6813 -- If statement sequence of entry call alternative is missing,
6814 -- then we can definitely fall through, and we post the error
6815 -- message on the entry call alternative itself.
6817 if No (Statements (ECA)) then
6820 -- If statement sequence of delay alternative is missing, then
6821 -- we can definitely fall through, and we post the error
6822 -- message on the delay alternative itself.
6824 -- Note: if both ECA and DCA are missing the return, then we
6825 -- post only one message, should be enough to fix the bugs.
6826 -- If not we will get a message next time on the DCA when the
6829 elsif No (Statements (DCA)) then
6832 -- Else check both statement sequences
6835 Check_Statement_Sequence (Statements (ECA));
6836 Check_Statement_Sequence (Statements (DCA));
6841 -- Conditional entry call, check entry call and else part
6843 -- Note: in expanded code, the conditional entry call has been
6844 -- converted to a set of expanded statements on which the check
6845 -- will work correctly in any case.
6847 elsif Kind = N_Conditional_Entry_Call then
6849 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
6852 -- If statement sequence of entry call alternative is missing,
6853 -- then we can definitely fall through, and we post the error
6854 -- message on the entry call alternative itself.
6856 if No (Statements (ECA)) then
6859 -- Else check statement sequence and else part
6862 Check_Statement_Sequence (Statements (ECA));
6863 Check_Statement_Sequence (Else_Statements (Last_Stm));
6869 -- If we fall through, issue appropriate message
6873 -- Kill warning if last statement is a raise exception call,
6874 -- or a pragma Assert (False). Note that with assertions enabled,
6875 -- such a pragma has been converted into a raise exception call
6876 -- already, so the Assert_False is for the assertions off case.
6878 if not Raise_Exception_Call and then not Assert_False then
6880 -- In GNATprove mode, it is an error to have a missing return
6882 Error_Msg_Warn := SPARK_Mode /= On;
6884 -- Issue error message or warning
6887 ("RETURN statement missing following this statement<<!",
6890 ("\Program_Error ]<<!", Last_Stm);
6893 -- Note: we set Err even though we have not issued a warning
6894 -- because we still have a case of a missing return. This is
6895 -- an extremely marginal case, probably will never be noticed
6896 -- but we might as well get it right.
6900 -- Otherwise we have the case of a procedure marked No_Return
6903 if not Raise_Exception_Call then
6904 if GNATprove_Mode then
6906 ("implied return after this statement would have raised "
6907 & "Program_Error", Last_Stm);
6909 -- In normal compilation mode, do not warn on a generated call
6910 -- (e.g. in the body of a renaming as completion).
6912 elsif Comes_From_Source (Last_Stm) then
6914 ("implied return after this statement will raise "
6915 & "Program_Error??", Last_Stm);
6918 Error_Msg_Warn := SPARK_Mode /= On;
6920 ("\procedure & is marked as No_Return<<!", Last_Stm, Proc);
6924 RE : constant Node_Id :=
6925 Make_Raise_Program_Error (Sloc (Last_Stm),
6926 Reason => PE_Implicit_Return);
6928 Insert_After (Last_Stm, RE);
6932 end Check_Statement_Sequence;
6934 -- Start of processing for Check_Returns
6938 Check_Statement_Sequence (Statements (HSS));
6940 if Present (Exception_Handlers (HSS)) then
6941 Handler := First_Non_Pragma (Exception_Handlers (HSS));
6942 while Present (Handler) loop
6943 Check_Statement_Sequence (Statements (Handler));
6944 Next_Non_Pragma (Handler);
6949 ----------------------------
6950 -- Check_Subprogram_Order --
6951 ----------------------------
6953 procedure Check_Subprogram_Order (N : Node_Id) is
6955 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
6956 -- This is used to check if S1 > S2 in the sense required by this test,
6957 -- for example nameab < namec, but name2 < name10.
6959 -----------------------------
6960 -- Subprogram_Name_Greater --
6961 -----------------------------
6963 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
6968 -- Deal with special case where names are identical except for a
6969 -- numerical suffix. These are handled specially, taking the numeric
6970 -- ordering from the suffix into account.
6973 while S1 (L1) in '0' .. '9' loop
6978 while S2 (L2) in '0' .. '9' loop
6982 -- If non-numeric parts non-equal, do straight compare
6984 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
6987 -- If non-numeric parts equal, compare suffixed numeric parts. Note
6988 -- that a missing suffix is treated as numeric zero in this test.
6992 while L1 < S1'Last loop
6994 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
6998 while L2 < S2'Last loop
7000 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
7005 end Subprogram_Name_Greater;
7007 -- Start of processing for Check_Subprogram_Order
7010 -- Check body in alpha order if this is option
7013 and then Style_Check_Order_Subprograms
7014 and then Nkind (N) = N_Subprogram_Body
7015 and then Comes_From_Source (N)
7016 and then In_Extended_Main_Source_Unit (N)
7020 renames Scope_Stack.Table
7021 (Scope_Stack.Last).Last_Subprogram_Name;
7023 Body_Id : constant Entity_Id :=
7024 Defining_Entity (Specification (N));
7027 Get_Decoded_Name_String (Chars (Body_Id));
7030 if Subprogram_Name_Greater
7031 (LSN.all, Name_Buffer (1 .. Name_Len))
7033 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7039 LSN := new String'(Name_Buffer (1 .. Name_Len));
7042 end Check_Subprogram_Order;
7044 ------------------------------
7045 -- Check_Subtype_Conformant --
7046 ------------------------------
7048 procedure Check_Subtype_Conformant
7049 (New_Id : Entity_Id;
7051 Err_Loc : Node_Id := Empty;
7052 Skip_Controlling_Formals : Boolean := False;
7053 Get_Inst : Boolean := False)
7056 pragma Warnings (Off, Result);
7059 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7060 Skip_Controlling_Formals => Skip_Controlling_Formals,
7061 Get_Inst => Get_Inst);
7062 end Check_Subtype_Conformant;
7064 -----------------------------------
7065 -- Check_Synchronized_Overriding --
7066 -----------------------------------
7068 procedure Check_Synchronized_Overriding
7069 (Def_Id : Entity_Id;
7070 Overridden_Subp : out Entity_Id)
7072 Ifaces_List : Elist_Id;
7076 function Matches_Prefixed_View_Profile
7077 (Prim_Params : List_Id;
7078 Iface_Params : List_Id) return Boolean;
7079 -- Determine whether a subprogram's parameter profile Prim_Params
7080 -- matches that of a potentially overridden interface subprogram
7081 -- Iface_Params. Also determine if the type of first parameter of
7082 -- Iface_Params is an implemented interface.
7084 -----------------------------------
7085 -- Matches_Prefixed_View_Profile --
7086 -----------------------------------
7088 function Matches_Prefixed_View_Profile
7089 (Prim_Params : List_Id;
7090 Iface_Params : List_Id) return Boolean
7092 function Is_Implemented
7093 (Ifaces_List : Elist_Id;
7094 Iface : Entity_Id) return Boolean;
7095 -- Determine if Iface is implemented by the current task or
7098 --------------------
7099 -- Is_Implemented --
7100 --------------------
7102 function Is_Implemented
7103 (Ifaces_List : Elist_Id;
7104 Iface : Entity_Id) return Boolean
7106 Iface_Elmt : Elmt_Id;
7109 Iface_Elmt := First_Elmt (Ifaces_List);
7110 while Present (Iface_Elmt) loop
7111 if Node (Iface_Elmt) = Iface then
7115 Next_Elmt (Iface_Elmt);
7123 Iface_Id : Entity_Id;
7124 Iface_Param : Node_Id;
7125 Iface_Typ : Entity_Id;
7126 Prim_Id : Entity_Id;
7127 Prim_Param : Node_Id;
7128 Prim_Typ : Entity_Id;
7130 -- Start of processing for Matches_Prefixed_View_Profile
7133 Iface_Param := First (Iface_Params);
7134 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7136 if Is_Access_Type (Iface_Typ) then
7137 Iface_Typ := Designated_Type (Iface_Typ);
7140 Prim_Param := First (Prim_Params);
7142 -- The first parameter of the potentially overridden subprogram must
7143 -- be an interface implemented by Prim.
7145 if not Is_Interface (Iface_Typ)
7146 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7151 -- The checks on the object parameters are done, so move on to the
7152 -- rest of the parameters.
7154 if not In_Scope then
7155 Prim_Param := Next (Prim_Param);
7158 Iface_Param := Next (Iface_Param);
7159 while Present (Iface_Param) and then Present (Prim_Param) loop
7160 Iface_Id := Defining_Identifier (Iface_Param);
7161 Iface_Typ := Find_Parameter_Type (Iface_Param);
7163 Prim_Id := Defining_Identifier (Prim_Param);
7164 Prim_Typ := Find_Parameter_Type (Prim_Param);
7166 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7167 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7168 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7170 Iface_Typ := Designated_Type (Iface_Typ);
7171 Prim_Typ := Designated_Type (Prim_Typ);
7174 -- Case of multiple interface types inside a parameter profile
7176 -- (Obj_Param : in out Iface; ...; Param : Iface)
7178 -- If the interface type is implemented, then the matching type in
7179 -- the primitive should be the implementing record type.
7181 if Ekind (Iface_Typ) = E_Record_Type
7182 and then Is_Interface (Iface_Typ)
7183 and then Is_Implemented (Ifaces_List, Iface_Typ)
7185 if Prim_Typ /= Typ then
7189 -- The two parameters must be both mode and subtype conformant
7191 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7193 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7202 -- One of the two lists contains more parameters than the other
7204 if Present (Iface_Param) or else Present (Prim_Param) then
7209 end Matches_Prefixed_View_Profile;
7211 -- Start of processing for Check_Synchronized_Overriding
7214 Overridden_Subp := Empty;
7216 -- Def_Id must be an entry or a subprogram. We should skip predefined
7217 -- primitives internally generated by the front end; however at this
7218 -- stage predefined primitives are still not fully decorated. As a
7219 -- minor optimization we skip here internally generated subprograms.
7221 if (Ekind (Def_Id) /= E_Entry
7222 and then Ekind (Def_Id) /= E_Function
7223 and then Ekind (Def_Id) /= E_Procedure)
7224 or else not Comes_From_Source (Def_Id)
7229 -- Search for the concurrent declaration since it contains the list of
7230 -- all implemented interfaces. In this case, the subprogram is declared
7231 -- within the scope of a protected or a task type.
7233 if Present (Scope (Def_Id))
7234 and then Is_Concurrent_Type (Scope (Def_Id))
7235 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7237 Typ := Scope (Def_Id);
7240 -- The enclosing scope is not a synchronized type and the subprogram
7243 elsif No (First_Formal (Def_Id)) then
7246 -- The subprogram has formals and hence it may be a primitive of a
7250 Typ := Etype (First_Formal (Def_Id));
7252 if Is_Access_Type (Typ) then
7253 Typ := Directly_Designated_Type (Typ);
7256 if Is_Concurrent_Type (Typ)
7257 and then not Is_Generic_Actual_Type (Typ)
7261 -- This case occurs when the concurrent type is declared within a
7262 -- generic unit. As a result the corresponding record has been built
7263 -- and used as the type of the first formal, we just have to retrieve
7264 -- the corresponding concurrent type.
7266 elsif Is_Concurrent_Record_Type (Typ)
7267 and then not Is_Class_Wide_Type (Typ)
7268 and then Present (Corresponding_Concurrent_Type (Typ))
7270 Typ := Corresponding_Concurrent_Type (Typ);
7278 -- There is no overriding to check if this is an inherited operation in
7279 -- a type derivation for a generic actual.
7281 Collect_Interfaces (Typ, Ifaces_List);
7283 if Is_Empty_Elmt_List (Ifaces_List) then
7287 -- Determine whether entry or subprogram Def_Id overrides a primitive
7288 -- operation that belongs to one of the interfaces in Ifaces_List.
7291 Candidate : Entity_Id := Empty;
7292 Hom : Entity_Id := Empty;
7293 Subp : Entity_Id := Empty;
7296 -- Traverse the homonym chain, looking for a potentially overridden
7297 -- subprogram that belongs to an implemented interface.
7299 Hom := Current_Entity_In_Scope (Def_Id);
7300 while Present (Hom) loop
7304 or else not Is_Overloadable (Subp)
7305 or else not Is_Primitive (Subp)
7306 or else not Is_Dispatching_Operation (Subp)
7307 or else not Present (Find_Dispatching_Type (Subp))
7308 or else not Is_Interface (Find_Dispatching_Type (Subp))
7312 -- Entries and procedures can override abstract or null interface
7315 elsif Ekind_In (Def_Id, E_Entry, E_Procedure)
7316 and then Ekind (Subp) = E_Procedure
7317 and then Matches_Prefixed_View_Profile
7318 (Parameter_Specifications (Parent (Def_Id)),
7319 Parameter_Specifications (Parent (Subp)))
7323 -- For an overridden subprogram Subp, check whether the mode
7324 -- of its first parameter is correct depending on the kind of
7325 -- synchronized type.
7328 Formal : constant Node_Id := First_Formal (Candidate);
7331 -- In order for an entry or a protected procedure to
7332 -- override, the first parameter of the overridden routine
7333 -- must be of mode "out", "in out", or access-to-variable.
7335 if Ekind_In (Candidate, E_Entry, E_Procedure)
7336 and then Is_Protected_Type (Typ)
7337 and then Ekind (Formal) /= E_In_Out_Parameter
7338 and then Ekind (Formal) /= E_Out_Parameter
7339 and then Nkind (Parameter_Type (Parent (Formal))) /=
7344 -- All other cases are OK since a task entry or routine does
7345 -- not have a restriction on the mode of the first parameter
7346 -- of the overridden interface routine.
7349 Overridden_Subp := Candidate;
7354 -- Functions can override abstract interface functions
7356 elsif Ekind (Def_Id) = E_Function
7357 and then Ekind (Subp) = E_Function
7358 and then Matches_Prefixed_View_Profile
7359 (Parameter_Specifications (Parent (Def_Id)),
7360 Parameter_Specifications (Parent (Subp)))
7361 and then Etype (Def_Id) = Etype (Subp)
7365 -- If an inherited subprogram is implemented by a protected
7366 -- function, then the first parameter of the inherited
7367 -- subprogram shall be of mode in, but not an access-to-
7368 -- variable parameter (RM 9.4(11/9)).
7370 if Present (First_Formal (Subp))
7371 and then Ekind (First_Formal (Subp)) = E_In_Parameter
7373 (not Is_Access_Type (Etype (First_Formal (Subp)))
7375 Is_Access_Constant (Etype (First_Formal (Subp))))
7377 Overridden_Subp := Subp;
7382 Hom := Homonym (Hom);
7385 -- After examining all candidates for overriding, we are left with
7386 -- the best match, which is a mode-incompatible interface routine.
7388 if In_Scope and then Present (Candidate) then
7389 Error_Msg_PT (Def_Id, Candidate);
7392 Overridden_Subp := Candidate;
7395 end Check_Synchronized_Overriding;
7397 ---------------------------
7398 -- Check_Type_Conformant --
7399 ---------------------------
7401 procedure Check_Type_Conformant
7402 (New_Id : Entity_Id;
7404 Err_Loc : Node_Id := Empty)
7407 pragma Warnings (Off, Result);
7410 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7411 end Check_Type_Conformant;
7413 ---------------------------
7414 -- Can_Override_Operator --
7415 ---------------------------
7417 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7421 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7425 Typ := Base_Type (Etype (First_Formal (Subp)));
7427 -- Check explicitly that the operation is a primitive of the type
7429 return Operator_Matches_Spec (Subp, Subp)
7430 and then not Is_Generic_Type (Typ)
7431 and then Scope (Subp) = Scope (Typ)
7432 and then not Is_Class_Wide_Type (Typ);
7434 end Can_Override_Operator;
7436 ----------------------
7437 -- Conforming_Types --
7438 ----------------------
7440 function Conforming_Types
7443 Ctype : Conformance_Type;
7444 Get_Inst : Boolean := False) return Boolean
7446 function Base_Types_Match
7448 Typ_2 : Entity_Id) return Boolean;
7449 -- If neither Typ_1 nor Typ_2 are generic actual types, or if they are
7450 -- in different scopes (e.g. parent and child instances), then verify
7451 -- that the base types are equal. Otherwise Typ_1 and Typ_2 must be on
7452 -- the same subtype chain. The whole purpose of this procedure is to
7453 -- prevent spurious ambiguities in an instantiation that may arise if
7454 -- two distinct generic types are instantiated with the same actual.
7456 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id;
7457 -- An access parameter can designate an incomplete type. If the
7458 -- incomplete type is the limited view of a type from a limited_
7459 -- with_clause, check whether the non-limited view is available.
7460 -- If it is a (non-limited) incomplete type, get the full view.
7462 function Matches_Limited_With_View
7464 Typ_2 : Entity_Id) return Boolean;
7465 -- Returns True if and only if either Typ_1 denotes a limited view of
7466 -- Typ_2 or Typ_2 denotes a limited view of Typ_1. This can arise when
7467 -- the limited with view of a type is used in a subprogram declaration
7468 -- and the subprogram body is in the scope of a regular with clause for
7469 -- the same unit. In such a case, the two type entities are considered
7470 -- identical for purposes of conformance checking.
7472 ----------------------
7473 -- Base_Types_Match --
7474 ----------------------
7476 function Base_Types_Match
7478 Typ_2 : Entity_Id) return Boolean
7480 Base_1 : constant Entity_Id := Base_Type (Typ_1);
7481 Base_2 : constant Entity_Id := Base_Type (Typ_2);
7484 if Typ_1 = Typ_2 then
7487 elsif Base_1 = Base_2 then
7489 -- The following is too permissive. A more precise test should
7490 -- check that the generic actual is an ancestor subtype of the
7493 -- See code in Find_Corresponding_Spec that applies an additional
7494 -- filter to handle accidental amiguities in instances.
7497 not Is_Generic_Actual_Type (Typ_1)
7498 or else not Is_Generic_Actual_Type (Typ_2)
7499 or else Scope (Typ_1) /= Scope (Typ_2);
7501 -- If Typ_2 is a generic actual type it is declared as the subtype of
7502 -- the actual. If that actual is itself a subtype we need to use its
7503 -- own base type to check for compatibility.
7505 elsif Ekind (Base_2) = Ekind (Typ_2)
7506 and then Base_1 = Base_Type (Base_2)
7510 elsif Ekind (Base_1) = Ekind (Typ_1)
7511 and then Base_2 = Base_Type (Base_1)
7518 end Base_Types_Match;
7520 --------------------------
7521 -- Find_Designated_Type --
7522 --------------------------
7524 function Find_Designated_Type (Typ : Entity_Id) return Entity_Id is
7528 Desig := Directly_Designated_Type (Typ);
7530 if Ekind (Desig) = E_Incomplete_Type then
7532 -- If regular incomplete type, get full view if available
7534 if Present (Full_View (Desig)) then
7535 Desig := Full_View (Desig);
7537 -- If limited view of a type, get non-limited view if available,
7538 -- and check again for a regular incomplete type.
7540 elsif Present (Non_Limited_View (Desig)) then
7541 Desig := Get_Full_View (Non_Limited_View (Desig));
7546 end Find_Designated_Type;
7548 -------------------------------
7549 -- Matches_Limited_With_View --
7550 -------------------------------
7552 function Matches_Limited_With_View
7554 Typ_2 : Entity_Id) return Boolean
7556 function Is_Matching_Limited_View
7558 View : Entity_Id) return Boolean;
7559 -- Determine whether non-limited view View denotes type Typ in some
7560 -- conformant fashion.
7562 ------------------------------
7563 -- Is_Matching_Limited_View --
7564 ------------------------------
7566 function Is_Matching_Limited_View
7568 View : Entity_Id) return Boolean
7570 Root_Typ : Entity_Id;
7571 Root_View : Entity_Id;
7574 -- The non-limited view directly denotes the type
7579 -- The type is a subtype of the non-limited view
7581 elsif Is_Subtype_Of (Typ, View) then
7584 -- Both the non-limited view and the type denote class-wide types
7586 elsif Is_Class_Wide_Type (Typ)
7587 and then Is_Class_Wide_Type (View)
7589 Root_Typ := Root_Type (Typ);
7590 Root_View := Root_Type (View);
7592 if Root_Typ = Root_View then
7595 -- An incomplete tagged type and its full view may receive two
7596 -- distinct class-wide types when the related package has not
7597 -- been analyzed yet.
7600 -- type T is tagged; -- CW_1
7601 -- type T is tagged null record; -- CW_2
7604 -- This is because the package lacks any semantic information
7605 -- that may eventually link both views of T. As a consequence,
7606 -- a client of the limited view of Pack will see CW_2 while a
7607 -- client of the non-limited view of Pack will see CW_1.
7609 elsif Is_Incomplete_Type (Root_Typ)
7610 and then Present (Full_View (Root_Typ))
7611 and then Full_View (Root_Typ) = Root_View
7615 elsif Is_Incomplete_Type (Root_View)
7616 and then Present (Full_View (Root_View))
7617 and then Full_View (Root_View) = Root_Typ
7624 end Is_Matching_Limited_View;
7626 -- Start of processing for Matches_Limited_With_View
7629 -- In some cases a type imported through a limited_with clause, and
7630 -- its non-limited view are both visible, for example in an anonymous
7631 -- access-to-class-wide type in a formal, or when building the body
7632 -- for a subprogram renaming after the subprogram has been frozen.
7633 -- In these cases both entities designate the same type. In addition,
7634 -- if one of them is an actual in an instance, it may be a subtype of
7635 -- the non-limited view of the other.
7637 if From_Limited_With (Typ_1)
7638 and then From_Limited_With (Typ_2)
7639 and then Available_View (Typ_1) = Available_View (Typ_2)
7643 elsif From_Limited_With (Typ_1) then
7644 return Is_Matching_Limited_View (Typ_2, Available_View (Typ_1));
7646 elsif From_Limited_With (Typ_2) then
7647 return Is_Matching_Limited_View (Typ_1, Available_View (Typ_2));
7652 end Matches_Limited_With_View;
7656 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7658 Type_1 : Entity_Id := T1;
7659 Type_2 : Entity_Id := T2;
7661 -- Start of processing for Conforming_Types
7664 -- The context is an instance association for a formal access-to-
7665 -- subprogram type; the formal parameter types require mapping because
7666 -- they may denote other formal parameters of the generic unit.
7669 Type_1 := Get_Instance_Of (T1);
7670 Type_2 := Get_Instance_Of (T2);
7673 -- If one of the types is a view of the other introduced by a limited
7674 -- with clause, treat these as conforming for all purposes.
7676 if Matches_Limited_With_View (T1, T2) then
7679 elsif Base_Types_Match (Type_1, Type_2) then
7680 if Ctype <= Mode_Conformant then
7685 Subtypes_Statically_Match (Type_1, Type_2)
7686 and then Dimensions_Match (Type_1, Type_2);
7689 elsif Is_Incomplete_Or_Private_Type (Type_1)
7690 and then Present (Full_View (Type_1))
7691 and then Base_Types_Match (Full_View (Type_1), Type_2)
7694 Ctype <= Mode_Conformant
7695 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7697 elsif Ekind (Type_2) = E_Incomplete_Type
7698 and then Present (Full_View (Type_2))
7699 and then Base_Types_Match (Type_1, Full_View (Type_2))
7702 Ctype <= Mode_Conformant
7703 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7705 elsif Is_Private_Type (Type_2)
7706 and then In_Instance
7707 and then Present (Full_View (Type_2))
7708 and then Base_Types_Match (Type_1, Full_View (Type_2))
7711 Ctype <= Mode_Conformant
7712 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7714 -- Another confusion between views in a nested instance with an
7715 -- actual private type whose full view is not in scope.
7717 elsif Ekind (Type_2) = E_Private_Subtype
7718 and then In_Instance
7719 and then Etype (Type_2) = Type_1
7723 -- In Ada 2012, incomplete types (including limited views) can appear
7724 -- as actuals in instantiations, where they are conformant to the
7725 -- corresponding incomplete formal.
7727 elsif Is_Incomplete_Type (Type_1)
7728 and then Is_Incomplete_Type (Type_2)
7729 and then In_Instance
7730 and then (Used_As_Generic_Actual (Type_1)
7731 or else Used_As_Generic_Actual (Type_2))
7736 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7737 -- treated recursively because they carry a signature. As far as
7738 -- conformance is concerned, convention plays no role, and either
7739 -- or both could be access to protected subprograms.
7741 Are_Anonymous_Access_To_Subprogram_Types :=
7742 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7743 E_Anonymous_Access_Protected_Subprogram_Type)
7745 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7746 E_Anonymous_Access_Protected_Subprogram_Type);
7748 -- Test anonymous access type case. For this case, static subtype
7749 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7750 -- the base types because we may have built internal subtype entities
7751 -- to handle null-excluding types (see Process_Formals).
7753 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7755 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7757 -- Ada 2005 (AI-254)
7759 or else Are_Anonymous_Access_To_Subprogram_Types
7762 Desig_1 : Entity_Id;
7763 Desig_2 : Entity_Id;
7766 -- In Ada 2005, access constant indicators must match for
7767 -- subtype conformance.
7769 if Ada_Version >= Ada_2005
7770 and then Ctype >= Subtype_Conformant
7772 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7777 Desig_1 := Find_Designated_Type (Type_1);
7778 Desig_2 := Find_Designated_Type (Type_2);
7780 -- If the context is an instance association for a formal
7781 -- access-to-subprogram type; formal access parameter designated
7782 -- types require mapping because they may denote other formal
7783 -- parameters of the generic unit.
7786 Desig_1 := Get_Instance_Of (Desig_1);
7787 Desig_2 := Get_Instance_Of (Desig_2);
7790 -- It is possible for a Class_Wide_Type to be introduced for an
7791 -- incomplete type, in which case there is a separate class_ wide
7792 -- type for the full view. The types conform if their Etypes
7793 -- conform, i.e. one may be the full view of the other. This can
7794 -- only happen in the context of an access parameter, other uses
7795 -- of an incomplete Class_Wide_Type are illegal.
7797 if Is_Class_Wide_Type (Desig_1)
7799 Is_Class_Wide_Type (Desig_2)
7803 (Etype (Base_Type (Desig_1)),
7804 Etype (Base_Type (Desig_2)), Ctype);
7806 elsif Are_Anonymous_Access_To_Subprogram_Types then
7807 if Ada_Version < Ada_2005 then
7809 Ctype = Type_Conformant
7810 or else Subtypes_Statically_Match (Desig_1, Desig_2);
7812 -- We must check the conformance of the signatures themselves
7816 Conformant : Boolean;
7819 (Desig_1, Desig_2, Ctype, False, Conformant);
7824 -- A limited view of an actual matches the corresponding
7825 -- incomplete formal.
7827 elsif Ekind (Desig_2) = E_Incomplete_Subtype
7828 and then From_Limited_With (Desig_2)
7829 and then Used_As_Generic_Actual (Etype (Desig_2))
7834 return Base_Type (Desig_1) = Base_Type (Desig_2)
7835 and then (Ctype = Type_Conformant
7837 Subtypes_Statically_Match (Desig_1, Desig_2));
7841 -- Otherwise definitely no match
7844 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7845 and then Is_Access_Type (Type_2))
7846 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7847 and then Is_Access_Type (Type_1)))
7850 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7852 May_Hide_Profile := True;
7857 end Conforming_Types;
7859 --------------------------
7860 -- Create_Extra_Formals --
7861 --------------------------
7863 procedure Create_Extra_Formals (E : Entity_Id) is
7864 First_Extra : Entity_Id := Empty;
7866 Last_Extra : Entity_Id := Empty;
7868 function Add_Extra_Formal
7869 (Assoc_Entity : Entity_Id;
7872 Suffix : String) return Entity_Id;
7873 -- Add an extra formal to the current list of formals and extra formals.
7874 -- The extra formal is added to the end of the list of extra formals,
7875 -- and also returned as the result. These formals are always of mode IN.
7876 -- The new formal has the type Typ, is declared in Scope, and its name
7877 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7878 -- The following suffixes are currently used. They should not be changed
7879 -- without coordinating with CodePeer, which makes use of these to
7880 -- provide better messages.
7882 -- O denotes the Constrained bit.
7883 -- L denotes the accessibility level.
7884 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7885 -- the full list in exp_ch6.BIP_Formal_Kind.
7887 ----------------------
7888 -- Add_Extra_Formal --
7889 ----------------------
7891 function Add_Extra_Formal
7892 (Assoc_Entity : Entity_Id;
7895 Suffix : String) return Entity_Id
7897 EF : constant Entity_Id :=
7898 Make_Defining_Identifier (Sloc (Assoc_Entity),
7899 Chars => New_External_Name (Chars (Assoc_Entity),
7903 -- A little optimization. Never generate an extra formal for the
7904 -- _init operand of an initialization procedure, since it could
7907 if Chars (Formal) = Name_uInit then
7911 Set_Ekind (EF, E_In_Parameter);
7912 Set_Actual_Subtype (EF, Typ);
7913 Set_Etype (EF, Typ);
7914 Set_Scope (EF, Scope);
7915 Set_Mechanism (EF, Default_Mechanism);
7916 Set_Formal_Validity (EF);
7918 if No (First_Extra) then
7920 Set_Extra_Formals (Scope, EF);
7923 if Present (Last_Extra) then
7924 Set_Extra_Formal (Last_Extra, EF);
7930 end Add_Extra_Formal;
7934 Formal_Type : Entity_Id;
7935 P_Formal : Entity_Id := Empty;
7937 -- Start of processing for Create_Extra_Formals
7940 -- We never generate extra formals if expansion is not active because we
7941 -- don't need them unless we are generating code.
7943 if not Expander_Active then
7947 -- No need to generate extra formals in interface thunks whose target
7948 -- primitive has no extra formals.
7950 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7954 -- If this is a derived subprogram then the subtypes of the parent
7955 -- subprogram's formal parameters will be used to determine the need
7956 -- for extra formals.
7958 if Is_Overloadable (E) and then Present (Alias (E)) then
7959 P_Formal := First_Formal (Alias (E));
7962 Formal := First_Formal (E);
7963 while Present (Formal) loop
7964 Last_Extra := Formal;
7965 Next_Formal (Formal);
7968 -- If Extra_Formals were already created, don't do it again. This
7969 -- situation may arise for subprogram types created as part of
7970 -- dispatching calls (see Expand_Dispatching_Call).
7972 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7976 -- If the subprogram is a predefined dispatching subprogram then don't
7977 -- generate any extra constrained or accessibility level formals. In
7978 -- general we suppress these for internal subprograms (by not calling
7979 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7980 -- generated stream attributes do get passed through because extra
7981 -- build-in-place formals are needed in some cases (limited 'Input).
7983 if Is_Predefined_Internal_Operation (E) then
7984 goto Test_For_Func_Result_Extras;
7987 Formal := First_Formal (E);
7988 while Present (Formal) loop
7990 -- Create extra formal for supporting the attribute 'Constrained.
7991 -- The case of a private type view without discriminants also
7992 -- requires the extra formal if the underlying type has defaulted
7995 if Ekind (Formal) /= E_In_Parameter then
7996 if Present (P_Formal) then
7997 Formal_Type := Etype (P_Formal);
7999 Formal_Type := Etype (Formal);
8002 -- Do not produce extra formals for Unchecked_Union parameters.
8003 -- Jump directly to the end of the loop.
8005 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
8006 goto Skip_Extra_Formal_Generation;
8009 if not Has_Discriminants (Formal_Type)
8010 and then Ekind (Formal_Type) in Private_Kind
8011 and then Present (Underlying_Type (Formal_Type))
8013 Formal_Type := Underlying_Type (Formal_Type);
8016 -- Suppress the extra formal if formal's subtype is constrained or
8017 -- indefinite, or we're compiling for Ada 2012 and the underlying
8018 -- type is tagged and limited. In Ada 2012, a limited tagged type
8019 -- can have defaulted discriminants, but 'Constrained is required
8020 -- to return True, so the formal is never needed (see AI05-0214).
8021 -- Note that this ensures consistency of calling sequences for
8022 -- dispatching operations when some types in a class have defaults
8023 -- on discriminants and others do not (and requiring the extra
8024 -- formal would introduce distributed overhead).
8026 -- If the type does not have a completion yet, treat as prior to
8027 -- Ada 2012 for consistency.
8029 if Has_Discriminants (Formal_Type)
8030 and then not Is_Constrained (Formal_Type)
8031 and then Is_Definite_Subtype (Formal_Type)
8032 and then (Ada_Version < Ada_2012
8033 or else No (Underlying_Type (Formal_Type))
8035 (Is_Limited_Type (Formal_Type)
8038 (Underlying_Type (Formal_Type)))))
8040 Set_Extra_Constrained
8041 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8045 -- Create extra formal for supporting accessibility checking. This
8046 -- is done for both anonymous access formals and formals of named
8047 -- access types that are marked as controlling formals. The latter
8048 -- case can occur when Expand_Dispatching_Call creates a subprogram
8049 -- type and substitutes the types of access-to-class-wide actuals
8050 -- for the anonymous access-to-specific-type of controlling formals.
8051 -- Base_Type is applied because in cases where there is a null
8052 -- exclusion the formal may have an access subtype.
8054 -- This is suppressed if we specifically suppress accessibility
8055 -- checks at the package level for either the subprogram, or the
8056 -- package in which it resides. However, we do not suppress it
8057 -- simply if the scope has accessibility checks suppressed, since
8058 -- this could cause trouble when clients are compiled with a
8059 -- different suppression setting. The explicit checks at the
8060 -- package level are safe from this point of view.
8062 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8063 or else (Is_Controlling_Formal (Formal)
8064 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8066 (Explicit_Suppress (E, Accessibility_Check)
8068 Explicit_Suppress (Scope (E), Accessibility_Check))
8071 or else Present (Extra_Accessibility (P_Formal)))
8073 Set_Extra_Accessibility
8074 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8077 -- This label is required when skipping extra formal generation for
8078 -- Unchecked_Union parameters.
8080 <<Skip_Extra_Formal_Generation>>
8082 if Present (P_Formal) then
8083 Next_Formal (P_Formal);
8086 Next_Formal (Formal);
8089 <<Test_For_Func_Result_Extras>>
8091 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8092 -- function call is ... determined by the point of call ...".
8094 if Needs_Result_Accessibility_Level (E) then
8095 Set_Extra_Accessibility_Of_Result
8096 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8099 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8100 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8102 if Is_Build_In_Place_Function (E) then
8104 Result_Subt : constant Entity_Id := Etype (E);
8105 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8106 Formal_Typ : Entity_Id;
8107 Subp_Decl : Node_Id;
8108 Discard : Entity_Id;
8111 -- In the case of functions with unconstrained result subtypes,
8112 -- add a 4-state formal indicating whether the return object is
8113 -- allocated by the caller (1), or should be allocated by the
8114 -- callee on the secondary stack (2), in the global heap (3), or
8115 -- in a user-defined storage pool (4). For the moment we just use
8116 -- Natural for the type of this formal. Note that this formal
8117 -- isn't usually needed in the case where the result subtype is
8118 -- constrained, but it is needed when the function has a tagged
8119 -- result, because generally such functions can be called in a
8120 -- dispatching context and such calls must be handled like calls
8121 -- to a class-wide function.
8123 if Needs_BIP_Alloc_Form (E) then
8126 (E, Standard_Natural,
8127 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8129 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8130 -- use a user-defined pool. This formal is not added on
8131 -- ZFP as those targets do not support pools.
8133 if RTE_Available (RE_Root_Storage_Pool_Ptr) then
8136 (E, RTE (RE_Root_Storage_Pool_Ptr),
8137 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8141 -- In the case of functions whose result type needs finalization,
8142 -- add an extra formal which represents the finalization master.
8144 if Needs_BIP_Finalization_Master (E) then
8147 (E, RTE (RE_Finalization_Master_Ptr),
8148 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8151 -- When the result type contains tasks, add two extra formals: the
8152 -- master of the tasks to be created, and the caller's activation
8155 if Has_Task (Full_Subt) then
8158 (E, RTE (RE_Master_Id),
8159 E, BIP_Formal_Suffix (BIP_Task_Master));
8162 (E, RTE (RE_Activation_Chain_Access),
8163 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8166 -- All build-in-place functions get an extra formal that will be
8167 -- passed the address of the return object within the caller.
8170 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8172 -- Incomplete_View_From_Limited_With is needed here because
8173 -- gigi gets confused if the designated type is the full view
8174 -- coming from a limited-with'ed package. In the normal case,
8175 -- (no limited with) Incomplete_View_From_Limited_With
8176 -- returns Result_Subt.
8178 Set_Directly_Designated_Type
8179 (Formal_Typ, Incomplete_View_From_Limited_With (Result_Subt));
8180 Set_Etype (Formal_Typ, Formal_Typ);
8181 Set_Depends_On_Private
8182 (Formal_Typ, Has_Private_Component (Formal_Typ));
8183 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8184 Set_Is_Access_Constant (Formal_Typ, False);
8186 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8187 -- the designated type comes from the limited view (for back-end
8190 Set_From_Limited_With
8191 (Formal_Typ, From_Limited_With (Result_Subt));
8193 Layout_Type (Formal_Typ);
8195 -- Force the definition of the Itype in case of internal function
8196 -- calls within the same or nested scope.
8198 if Is_Subprogram_Or_Generic_Subprogram (E) then
8199 Subp_Decl := Parent (E);
8201 -- The insertion point for an Itype reference should be after
8202 -- the unit declaration node of the subprogram. An exception
8203 -- to this are inherited operations from a parent type in which
8204 -- case the derived type acts as their parent.
8206 if Nkind_In (Subp_Decl, N_Function_Specification,
8207 N_Procedure_Specification)
8209 Subp_Decl := Parent (Subp_Decl);
8212 Build_Itype_Reference (Formal_Typ, Subp_Decl);
8217 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8221 -- If this is an instance of a generic, we need to have extra formals
8224 if Is_Generic_Instance (E) and then Present (Alias (E)) then
8225 Set_Extra_Formals (Alias (E), Extra_Formals (E));
8227 end Create_Extra_Formals;
8229 -----------------------------
8230 -- Enter_Overloaded_Entity --
8231 -----------------------------
8233 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8234 function Matches_Predefined_Op return Boolean;
8235 -- This returns an approximation of whether S matches a predefined
8236 -- operator, based on the operator symbol, and the parameter and result
8237 -- types. The rules are scattered throughout chapter 4 of the Ada RM.
8239 ---------------------------
8240 -- Matches_Predefined_Op --
8241 ---------------------------
8243 function Matches_Predefined_Op return Boolean is
8244 Formal_1 : constant Entity_Id := First_Formal (S);
8245 Formal_2 : constant Entity_Id := Next_Formal (Formal_1);
8246 Op : constant Name_Id := Chars (S);
8247 Result_Type : constant Entity_Id := Base_Type (Etype (S));
8248 Type_1 : constant Entity_Id := Base_Type (Etype (Formal_1));
8253 if Present (Formal_2) then
8255 Type_2 : constant Entity_Id := Base_Type (Etype (Formal_2));
8258 -- All but "&" and "**" have same-types parameters
8267 if Type_1 /= Type_2 then
8272 -- Check parameter and result types
8280 Is_Boolean_Type (Result_Type)
8281 and then Result_Type = Type_1;
8287 Is_Integer_Type (Result_Type)
8288 and then Result_Type = Type_1;
8296 Is_Numeric_Type (Result_Type)
8297 and then Result_Type = Type_1;
8303 Is_Boolean_Type (Result_Type)
8304 and then not Is_Limited_Type (Type_1);
8312 Is_Boolean_Type (Result_Type)
8313 and then (Is_Array_Type (Type_1)
8314 or else Is_Scalar_Type (Type_1));
8316 when Name_Op_Concat =>
8317 return Is_Array_Type (Result_Type);
8319 when Name_Op_Expon =>
8321 (Is_Integer_Type (Result_Type)
8322 or else Is_Floating_Point_Type (Result_Type))
8323 and then Result_Type = Type_1
8324 and then Type_2 = Standard_Integer;
8327 raise Program_Error;
8340 Is_Numeric_Type (Result_Type)
8341 and then Result_Type = Type_1;
8345 Is_Boolean_Type (Result_Type)
8346 and then Result_Type = Type_1;
8349 raise Program_Error;
8352 end Matches_Predefined_Op;
8356 E : Entity_Id := Current_Entity_In_Scope (S);
8357 C_E : Entity_Id := Current_Entity (S);
8359 -- Start of processing for Enter_Overloaded_Entity
8363 Set_Has_Homonym (E);
8364 Set_Has_Homonym (S);
8367 Set_Is_Immediately_Visible (S);
8368 Set_Scope (S, Current_Scope);
8370 -- Chain new entity if front of homonym in current scope, so that
8371 -- homonyms are contiguous.
8373 if Present (E) and then E /= C_E then
8374 while Homonym (C_E) /= E loop
8375 C_E := Homonym (C_E);
8378 Set_Homonym (C_E, S);
8382 Set_Current_Entity (S);
8387 if Is_Inherited_Operation (S) then
8388 Append_Inherited_Subprogram (S);
8390 Append_Entity (S, Current_Scope);
8393 Set_Public_Status (S);
8395 if Debug_Flag_E then
8396 Write_Str ("New overloaded entity chain: ");
8397 Write_Name (Chars (S));
8400 while Present (E) loop
8401 Write_Str (" "); Write_Int (Int (E));
8408 -- Generate warning for hiding
8411 and then Comes_From_Source (S)
8412 and then In_Extended_Main_Source_Unit (S)
8419 -- Warn unless genuine overloading. Do not emit warning on
8420 -- hiding predefined operators in Standard (these are either an
8421 -- (artifact of our implicit declarations, or simple noise) but
8422 -- keep warning on a operator defined on a local subtype, because
8423 -- of the real danger that different operators may be applied in
8424 -- various parts of the program.
8426 -- Note that if E and S have the same scope, there is never any
8427 -- hiding. Either the two conflict, and the program is illegal,
8428 -- or S is overriding an implicit inherited subprogram.
8430 if Scope (E) /= Scope (S)
8431 and then (not Is_Overloadable (E)
8432 or else Subtype_Conformant (E, S))
8433 and then (Is_Immediately_Visible (E)
8434 or else Is_Potentially_Use_Visible (S))
8436 if Scope (E) = Standard_Standard then
8437 if Nkind (S) = N_Defining_Operator_Symbol
8438 and then Scope (Base_Type (Etype (First_Formal (S)))) /=
8440 and then Matches_Predefined_Op
8443 ("declaration of & hides predefined operator?h?", S);
8446 -- E not immediately within Standard
8449 Error_Msg_Sloc := Sloc (E);
8450 Error_Msg_N ("declaration of & hides one #?h?", S);
8455 end Enter_Overloaded_Entity;
8457 -----------------------------
8458 -- Check_Untagged_Equality --
8459 -----------------------------
8461 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8462 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8463 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8467 -- This check applies only if we have a subprogram declaration with an
8468 -- untagged record type.
8470 if Nkind (Decl) /= N_Subprogram_Declaration
8471 or else not Is_Record_Type (Typ)
8472 or else Is_Tagged_Type (Typ)
8477 -- In Ada 2012 case, we will output errors or warnings depending on
8478 -- the setting of debug flag -gnatd.E.
8480 if Ada_Version >= Ada_2012 then
8481 Error_Msg_Warn := Debug_Flag_Dot_EE;
8483 -- In earlier versions of Ada, nothing to do unless we are warning on
8484 -- Ada 2012 incompatibilities (Warn_On_Ada_2012_Incompatibility set).
8487 if not Warn_On_Ada_2012_Compatibility then
8492 -- Cases where the type has already been frozen
8494 if Is_Frozen (Typ) then
8496 -- If the type is not declared in a package, or if we are in the body
8497 -- of the package or in some other scope, the new operation is not
8498 -- primitive, and therefore legal, though suspicious. Should we
8499 -- generate a warning in this case ???
8501 if Ekind (Scope (Typ)) /= E_Package
8502 or else Scope (Typ) /= Current_Scope
8506 -- If the type is a generic actual (sub)type, the operation is not
8507 -- primitive either because the base type is declared elsewhere.
8509 elsif Is_Generic_Actual_Type (Typ) then
8512 -- Here we have a definite error of declaration after freezing
8515 if Ada_Version >= Ada_2012 then
8517 ("equality operator must be declared before type & is "
8518 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)<<", Eq_Op, Typ);
8520 -- In Ada 2012 mode with error turned to warning, output one
8521 -- more warning to warn that the equality operation may not
8522 -- compose. This is the consequence of ignoring the error.
8524 if Error_Msg_Warn then
8525 Error_Msg_N ("\equality operation may not compose??", Eq_Op);
8530 ("equality operator must be declared before type& is "
8531 & "frozen (RM 4.5.2 (9.8)) (Ada 2012)?y?", Eq_Op, Typ);
8534 -- If we are in the package body, we could just move the
8535 -- declaration to the package spec, so add a message saying that.
8537 if In_Package_Body (Scope (Typ)) then
8538 if Ada_Version >= Ada_2012 then
8540 ("\move declaration to package spec<<", Eq_Op);
8543 ("\move declaration to package spec (Ada 2012)?y?", Eq_Op);
8546 -- Otherwise try to find the freezing point
8549 Obj_Decl := Next (Parent (Typ));
8550 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8551 if Nkind (Obj_Decl) = N_Object_Declaration
8552 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8554 -- Freezing point, output warnings
8556 if Ada_Version >= Ada_2012 then
8558 ("type& is frozen by declaration??", Obj_Decl, Typ);
8560 ("\an equality operator cannot be declared after "
8565 ("type& is frozen by declaration (Ada 2012)?y?",
8568 ("\an equality operator cannot be declared after "
8569 & "this point (Ada 2012)?y?",
8581 -- Here if type is not frozen yet. It is illegal to have a primitive
8582 -- equality declared in the private part if the type is visible.
8584 elsif not In_Same_List (Parent (Typ), Decl)
8585 and then not Is_Limited_Type (Typ)
8587 -- Shouldn't we give an RM reference here???
8589 if Ada_Version >= Ada_2012 then
8591 ("equality operator appears too late<<", Eq_Op);
8594 ("equality operator appears too late (Ada 2012)?y?", Eq_Op);
8597 -- No error detected
8602 end Check_Untagged_Equality;
8604 -----------------------------
8605 -- Find_Corresponding_Spec --
8606 -----------------------------
8608 function Find_Corresponding_Spec
8610 Post_Error : Boolean := True) return Entity_Id
8612 Spec : constant Node_Id := Specification (N);
8613 Designator : constant Entity_Id := Defining_Entity (Spec);
8617 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8618 -- Even if fully conformant, a body may depend on a generic actual when
8619 -- the spec does not, or vice versa, in which case they were distinct
8620 -- entities in the generic.
8622 -------------------------------
8623 -- Different_Generic_Profile --
8624 -------------------------------
8626 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8629 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8630 -- Check that the types of corresponding formals have the same
8631 -- generic actual if any. We have to account for subtypes of a
8632 -- generic formal, declared between a spec and a body, which may
8633 -- appear distinct in an instance but matched in the generic, and
8634 -- the subtype may be used either in the spec or the body of the
8635 -- subprogram being checked.
8637 -------------------------
8638 -- Same_Generic_Actual --
8639 -------------------------
8641 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8643 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean;
8644 -- Predicate to check whether S1 is a subtype of S2 in the source
8647 -------------------------
8648 -- Is_Declared_Subtype --
8649 -------------------------
8651 function Is_Declared_Subtype (S1, S2 : Entity_Id) return Boolean is
8653 return Comes_From_Source (Parent (S1))
8654 and then Nkind (Parent (S1)) = N_Subtype_Declaration
8655 and then Is_Entity_Name (Subtype_Indication (Parent (S1)))
8656 and then Entity (Subtype_Indication (Parent (S1))) = S2;
8657 end Is_Declared_Subtype;
8659 -- Start of processing for Same_Generic_Actual
8662 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8663 or else Is_Declared_Subtype (T1, T2)
8664 or else Is_Declared_Subtype (T2, T1);
8665 end Same_Generic_Actual;
8667 -- Start of processing for Different_Generic_Profile
8670 if not In_Instance then
8673 elsif Ekind (E) = E_Function
8674 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8679 F1 := First_Formal (Designator);
8680 F2 := First_Formal (E);
8681 while Present (F1) loop
8682 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8691 end Different_Generic_Profile;
8693 -- Start of processing for Find_Corresponding_Spec
8696 E := Current_Entity (Designator);
8697 while Present (E) loop
8699 -- We are looking for a matching spec. It must have the same scope,
8700 -- and the same name, and either be type conformant, or be the case
8701 -- of a library procedure spec and its body (which belong to one
8702 -- another regardless of whether they are type conformant or not).
8704 if Scope (E) = Current_Scope then
8705 if Current_Scope = Standard_Standard
8706 or else (Ekind (E) = Ekind (Designator)
8707 and then Type_Conformant (E, Designator))
8709 -- Within an instantiation, we know that spec and body are
8710 -- subtype conformant, because they were subtype conformant in
8711 -- the generic. We choose the subtype-conformant entity here as
8712 -- well, to resolve spurious ambiguities in the instance that
8713 -- were not present in the generic (i.e. when two different
8714 -- types are given the same actual). If we are looking for a
8715 -- spec to match a body, full conformance is expected.
8719 -- Inherit the convention and "ghostness" of the matching
8720 -- spec to ensure proper full and subtype conformance.
8722 Set_Convention (Designator, Convention (E));
8724 -- Skip past subprogram bodies and subprogram renamings that
8725 -- may appear to have a matching spec, but that aren't fully
8726 -- conformant with it. That can occur in cases where an
8727 -- actual type causes unrelated homographs in the instance.
8729 if Nkind_In (N, N_Subprogram_Body,
8730 N_Subprogram_Renaming_Declaration)
8731 and then Present (Homonym (E))
8732 and then not Fully_Conformant (Designator, E)
8736 elsif not Subtype_Conformant (Designator, E) then
8739 elsif Different_Generic_Profile (E) then
8744 -- Ada 2012 (AI05-0165): For internally generated bodies of
8745 -- null procedures locate the internally generated spec. We
8746 -- enforce mode conformance since a tagged type may inherit
8747 -- from interfaces several null primitives which differ only
8748 -- in the mode of the formals.
8750 if not (Comes_From_Source (E))
8751 and then Is_Null_Procedure (E)
8752 and then not Mode_Conformant (Designator, E)
8756 -- For null procedures coming from source that are completions,
8757 -- analysis of the generated body will establish the link.
8759 elsif Comes_From_Source (E)
8760 and then Nkind (Spec) = N_Procedure_Specification
8761 and then Null_Present (Spec)
8765 -- Expression functions can be completions, but cannot be
8766 -- completed by an explicit body.
8768 elsif Comes_From_Source (E)
8769 and then Comes_From_Source (N)
8770 and then Nkind (N) = N_Subprogram_Body
8771 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
8772 N_Expression_Function
8774 Error_Msg_Sloc := Sloc (E);
8775 Error_Msg_N ("body conflicts with expression function#", N);
8778 elsif not Has_Completion (E) then
8779 if Nkind (N) /= N_Subprogram_Body_Stub then
8780 Set_Corresponding_Spec (N, E);
8783 Set_Has_Completion (E);
8786 elsif Nkind (Parent (N)) = N_Subunit then
8788 -- If this is the proper body of a subunit, the completion
8789 -- flag is set when analyzing the stub.
8793 -- If E is an internal function with a controlling result that
8794 -- was created for an operation inherited by a null extension,
8795 -- it may be overridden by a body without a previous spec (one
8796 -- more reason why these should be shunned). In that case we
8797 -- remove the generated body if present, because the current
8798 -- one is the explicit overriding.
8800 elsif Ekind (E) = E_Function
8801 and then Ada_Version >= Ada_2005
8802 and then not Comes_From_Source (E)
8803 and then Has_Controlling_Result (E)
8804 and then Is_Null_Extension (Etype (E))
8805 and then Comes_From_Source (Spec)
8807 Set_Has_Completion (E, False);
8810 and then Nkind (Parent (E)) = N_Function_Specification
8813 (Unit_Declaration_Node
8814 (Corresponding_Body (Unit_Declaration_Node (E))));
8818 -- If expansion is disabled, or if the wrapper function has
8819 -- not been generated yet, this a late body overriding an
8820 -- inherited operation, or it is an overriding by some other
8821 -- declaration before the controlling result is frozen. In
8822 -- either case this is a declaration of a new entity.
8828 -- If the body already exists, then this is an error unless
8829 -- the previous declaration is the implicit declaration of a
8830 -- derived subprogram. It is also legal for an instance to
8831 -- contain type conformant overloadable declarations (but the
8832 -- generic declaration may not), per 8.3(26/2).
8834 elsif No (Alias (E))
8835 and then not Is_Intrinsic_Subprogram (E)
8836 and then not In_Instance
8839 Error_Msg_Sloc := Sloc (E);
8841 if Is_Imported (E) then
8843 ("body not allowed for imported subprogram & declared#",
8846 Error_Msg_NE ("duplicate body for & declared#", N, E);
8850 -- Child units cannot be overloaded, so a conformance mismatch
8851 -- between body and a previous spec is an error.
8853 elsif Is_Child_Unit (E)
8855 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8857 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8862 ("body of child unit does not match previous declaration", N);
8870 -- On exit, we know that no previous declaration of subprogram exists
8873 end Find_Corresponding_Spec;
8875 ----------------------
8876 -- Fully_Conformant --
8877 ----------------------
8879 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8882 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8884 end Fully_Conformant;
8886 ----------------------------------
8887 -- Fully_Conformant_Expressions --
8888 ----------------------------------
8890 function Fully_Conformant_Expressions
8891 (Given_E1 : Node_Id;
8892 Given_E2 : Node_Id) return Boolean
8894 E1 : constant Node_Id := Original_Node (Given_E1);
8895 E2 : constant Node_Id := Original_Node (Given_E2);
8896 -- We always test conformance on original nodes, since it is possible
8897 -- for analysis and/or expansion to make things look as though they
8898 -- conform when they do not, e.g. by converting 1+2 into 3.
8900 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8901 renames Fully_Conformant_Expressions;
8903 function FCL (L1, L2 : List_Id) return Boolean;
8904 -- Compare elements of two lists for conformance. Elements have to be
8905 -- conformant, and actuals inserted as default parameters do not match
8906 -- explicit actuals with the same value.
8908 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8909 -- Compare an operator node with a function call
8915 function FCL (L1, L2 : List_Id) return Boolean is
8919 if L1 = No_List then
8925 if L2 = No_List then
8931 -- Compare two lists, skipping rewrite insertions (we want to compare
8932 -- the original trees, not the expanded versions).
8935 if Is_Rewrite_Insertion (N1) then
8937 elsif Is_Rewrite_Insertion (N2) then
8943 elsif not FCE (N1, N2) then
8956 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8957 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8962 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8967 Act := First (Actuals);
8969 if Nkind (Op_Node) in N_Binary_Op then
8970 if not FCE (Left_Opnd (Op_Node), Act) then
8977 return Present (Act)
8978 and then FCE (Right_Opnd (Op_Node), Act)
8979 and then No (Next (Act));
8983 -- Start of processing for Fully_Conformant_Expressions
8986 -- Nonconformant if paren count does not match. Note: if some idiot
8987 -- complains that we don't do this right for more than 3 levels of
8988 -- parentheses, they will be treated with the respect they deserve.
8990 if Paren_Count (E1) /= Paren_Count (E2) then
8993 -- If same entities are referenced, then they are conformant even if
8994 -- they have different forms (RM 8.3.1(19-20)).
8996 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8997 if Present (Entity (E1)) then
8998 return Entity (E1) = Entity (E2)
9000 -- One may be a discriminant that has been replaced by the
9001 -- corresponding discriminal.
9004 (Chars (Entity (E1)) = Chars (Entity (E2))
9005 and then Ekind (Entity (E1)) = E_Discriminant
9006 and then Ekind (Entity (E2)) = E_In_Parameter)
9008 -- The discriminant of a protected type is transformed into
9009 -- a local constant and then into a parameter of a protected
9013 (Ekind (Entity (E1)) = E_Constant
9014 and then Ekind (Entity (E2)) = E_In_Parameter
9015 and then Present (Discriminal_Link (Entity (E1)))
9016 and then Discriminal_Link (Entity (E1)) =
9017 Discriminal_Link (Entity (E2)))
9019 -- AI12-050: The loop variables of quantified expressions
9020 -- match if they have the same identifier, even though they
9021 -- are different entities.
9024 (Chars (Entity (E1)) = Chars (Entity (E2))
9025 and then Ekind (Entity (E1)) = E_Loop_Parameter
9026 and then Ekind (Entity (E2)) = E_Loop_Parameter);
9028 elsif Nkind (E1) = N_Expanded_Name
9029 and then Nkind (E2) = N_Expanded_Name
9030 and then Nkind (Selector_Name (E1)) = N_Character_Literal
9031 and then Nkind (Selector_Name (E2)) = N_Character_Literal
9033 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
9036 -- Identifiers in component associations don't always have
9037 -- entities, but their names must conform.
9039 return Nkind (E1) = N_Identifier
9040 and then Nkind (E2) = N_Identifier
9041 and then Chars (E1) = Chars (E2);
9044 elsif Nkind (E1) = N_Character_Literal
9045 and then Nkind (E2) = N_Expanded_Name
9047 return Nkind (Selector_Name (E2)) = N_Character_Literal
9048 and then Chars (E1) = Chars (Selector_Name (E2));
9050 elsif Nkind (E2) = N_Character_Literal
9051 and then Nkind (E1) = N_Expanded_Name
9053 return Nkind (Selector_Name (E1)) = N_Character_Literal
9054 and then Chars (E2) = Chars (Selector_Name (E1));
9056 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
9057 return FCO (E1, E2);
9059 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
9060 return FCO (E2, E1);
9062 -- Otherwise we must have the same syntactic entity
9064 elsif Nkind (E1) /= Nkind (E2) then
9067 -- At this point, we specialize by node type
9073 FCL (Expressions (E1), Expressions (E2))
9075 FCL (Component_Associations (E1),
9076 Component_Associations (E2));
9079 if Nkind (Expression (E1)) = N_Qualified_Expression
9081 Nkind (Expression (E2)) = N_Qualified_Expression
9083 return FCE (Expression (E1), Expression (E2));
9085 -- Check that the subtype marks and any constraints
9090 Indic1 : constant Node_Id := Expression (E1);
9091 Indic2 : constant Node_Id := Expression (E2);
9096 if Nkind (Indic1) /= N_Subtype_Indication then
9098 Nkind (Indic2) /= N_Subtype_Indication
9099 and then Entity (Indic1) = Entity (Indic2);
9101 elsif Nkind (Indic2) /= N_Subtype_Indication then
9103 Nkind (Indic1) /= N_Subtype_Indication
9104 and then Entity (Indic1) = Entity (Indic2);
9107 if Entity (Subtype_Mark (Indic1)) /=
9108 Entity (Subtype_Mark (Indic2))
9113 Elt1 := First (Constraints (Constraint (Indic1)));
9114 Elt2 := First (Constraints (Constraint (Indic2)));
9115 while Present (Elt1) and then Present (Elt2) loop
9116 if not FCE (Elt1, Elt2) then
9129 when N_Attribute_Reference =>
9131 Attribute_Name (E1) = Attribute_Name (E2)
9132 and then FCL (Expressions (E1), Expressions (E2));
9136 Entity (E1) = Entity (E2)
9137 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
9138 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
9140 when N_Membership_Test
9144 FCE (Left_Opnd (E1), Left_Opnd (E2))
9146 FCE (Right_Opnd (E1), Right_Opnd (E2));
9148 when N_Case_Expression =>
9154 if not FCE (Expression (E1), Expression (E2)) then
9158 Alt1 := First (Alternatives (E1));
9159 Alt2 := First (Alternatives (E2));
9161 if Present (Alt1) /= Present (Alt2) then
9163 elsif No (Alt1) then
9167 if not FCE (Expression (Alt1), Expression (Alt2))
9168 or else not FCL (Discrete_Choices (Alt1),
9169 Discrete_Choices (Alt2))
9180 when N_Character_Literal =>
9182 Char_Literal_Value (E1) = Char_Literal_Value (E2);
9184 when N_Component_Association =>
9186 FCL (Choices (E1), Choices (E2))
9188 FCE (Expression (E1), Expression (E2));
9190 when N_Explicit_Dereference =>
9192 FCE (Prefix (E1), Prefix (E2));
9194 when N_Extension_Aggregate =>
9196 FCL (Expressions (E1), Expressions (E2))
9197 and then Null_Record_Present (E1) =
9198 Null_Record_Present (E2)
9199 and then FCL (Component_Associations (E1),
9200 Component_Associations (E2));
9202 when N_Function_Call =>
9204 FCE (Name (E1), Name (E2))
9206 FCL (Parameter_Associations (E1),
9207 Parameter_Associations (E2));
9209 when N_If_Expression =>
9211 FCL (Expressions (E1), Expressions (E2));
9213 when N_Indexed_Component =>
9215 FCE (Prefix (E1), Prefix (E2))
9217 FCL (Expressions (E1), Expressions (E2));
9219 when N_Integer_Literal =>
9220 return (Intval (E1) = Intval (E2));
9225 when N_Operator_Symbol =>
9227 Chars (E1) = Chars (E2);
9229 when N_Others_Choice =>
9232 when N_Parameter_Association =>
9234 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
9235 and then FCE (Explicit_Actual_Parameter (E1),
9236 Explicit_Actual_Parameter (E2));
9238 when N_Qualified_Expression
9240 | N_Unchecked_Type_Conversion
9243 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9245 FCE (Expression (E1), Expression (E2));
9247 when N_Quantified_Expression =>
9248 if not FCE (Condition (E1), Condition (E2)) then
9252 if Present (Loop_Parameter_Specification (E1))
9253 and then Present (Loop_Parameter_Specification (E2))
9256 L1 : constant Node_Id :=
9257 Loop_Parameter_Specification (E1);
9258 L2 : constant Node_Id :=
9259 Loop_Parameter_Specification (E2);
9263 Reverse_Present (L1) = Reverse_Present (L2)
9265 FCE (Defining_Identifier (L1),
9266 Defining_Identifier (L2))
9268 FCE (Discrete_Subtype_Definition (L1),
9269 Discrete_Subtype_Definition (L2));
9272 elsif Present (Iterator_Specification (E1))
9273 and then Present (Iterator_Specification (E2))
9276 I1 : constant Node_Id := Iterator_Specification (E1);
9277 I2 : constant Node_Id := Iterator_Specification (E2);
9281 FCE (Defining_Identifier (I1),
9282 Defining_Identifier (I2))
9284 Of_Present (I1) = Of_Present (I2)
9286 Reverse_Present (I1) = Reverse_Present (I2)
9287 and then FCE (Name (I1), Name (I2))
9288 and then FCE (Subtype_Indication (I1),
9289 Subtype_Indication (I2));
9292 -- The quantified expressions used different specifications to
9293 -- walk their respective ranges.
9301 FCE (Low_Bound (E1), Low_Bound (E2))
9303 FCE (High_Bound (E1), High_Bound (E2));
9305 when N_Real_Literal =>
9306 return (Realval (E1) = Realval (E2));
9308 when N_Selected_Component =>
9310 FCE (Prefix (E1), Prefix (E2))
9312 FCE (Selector_Name (E1), Selector_Name (E2));
9316 FCE (Prefix (E1), Prefix (E2))
9318 FCE (Discrete_Range (E1), Discrete_Range (E2));
9320 when N_String_Literal =>
9322 S1 : constant String_Id := Strval (E1);
9323 S2 : constant String_Id := Strval (E2);
9324 L1 : constant Nat := String_Length (S1);
9325 L2 : constant Nat := String_Length (S2);
9332 for J in 1 .. L1 loop
9333 if Get_String_Char (S1, J) /=
9334 Get_String_Char (S2, J)
9346 Entity (E1) = Entity (E2)
9348 FCE (Right_Opnd (E1), Right_Opnd (E2));
9350 -- All other node types cannot appear in this context. Strictly
9351 -- we should raise a fatal internal error. Instead we just ignore
9352 -- the nodes. This means that if anyone makes a mistake in the
9353 -- expander and mucks an expression tree irretrievably, the result
9354 -- will be a failure to detect a (probably very obscure) case
9355 -- of non-conformance, which is better than bombing on some
9356 -- case where two expressions do in fact conform.
9362 end Fully_Conformant_Expressions;
9364 ----------------------------------------
9365 -- Fully_Conformant_Discrete_Subtypes --
9366 ----------------------------------------
9368 function Fully_Conformant_Discrete_Subtypes
9369 (Given_S1 : Node_Id;
9370 Given_S2 : Node_Id) return Boolean
9372 S1 : constant Node_Id := Original_Node (Given_S1);
9373 S2 : constant Node_Id := Original_Node (Given_S2);
9375 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9376 -- Special-case for a bound given by a discriminant, which in the body
9377 -- is replaced with the discriminal of the enclosing type.
9379 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9380 -- Check both bounds
9382 -----------------------
9383 -- Conforming_Bounds --
9384 -----------------------
9386 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9388 if Is_Entity_Name (B1)
9389 and then Is_Entity_Name (B2)
9390 and then Ekind (Entity (B1)) = E_Discriminant
9392 return Chars (B1) = Chars (B2);
9395 return Fully_Conformant_Expressions (B1, B2);
9397 end Conforming_Bounds;
9399 -----------------------
9400 -- Conforming_Ranges --
9401 -----------------------
9403 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9406 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9408 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9409 end Conforming_Ranges;
9411 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9414 if Nkind (S1) /= Nkind (S2) then
9417 elsif Is_Entity_Name (S1) then
9418 return Entity (S1) = Entity (S2);
9420 elsif Nkind (S1) = N_Range then
9421 return Conforming_Ranges (S1, S2);
9423 elsif Nkind (S1) = N_Subtype_Indication then
9425 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9428 (Range_Expression (Constraint (S1)),
9429 Range_Expression (Constraint (S2)));
9433 end Fully_Conformant_Discrete_Subtypes;
9435 --------------------
9436 -- Install_Entity --
9437 --------------------
9439 procedure Install_Entity (E : Entity_Id) is
9440 Prev : constant Entity_Id := Current_Entity (E);
9442 Set_Is_Immediately_Visible (E);
9443 Set_Current_Entity (E);
9444 Set_Homonym (E, Prev);
9447 ---------------------
9448 -- Install_Formals --
9449 ---------------------
9451 procedure Install_Formals (Id : Entity_Id) is
9454 F := First_Formal (Id);
9455 while Present (F) loop
9459 end Install_Formals;
9461 -----------------------------
9462 -- Is_Interface_Conformant --
9463 -----------------------------
9465 function Is_Interface_Conformant
9466 (Tagged_Type : Entity_Id;
9467 Iface_Prim : Entity_Id;
9468 Prim : Entity_Id) return Boolean
9470 -- The operation may in fact be an inherited (implicit) operation
9471 -- rather than the original interface primitive, so retrieve the
9472 -- ultimate ancestor.
9474 Iface : constant Entity_Id :=
9475 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9476 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9478 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9479 -- Return the controlling formal of Prim
9481 ------------------------
9482 -- Controlling_Formal --
9483 ------------------------
9485 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9489 E := First_Entity (Prim);
9490 while Present (E) loop
9491 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9499 end Controlling_Formal;
9503 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9504 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9506 -- Start of processing for Is_Interface_Conformant
9509 pragma Assert (Is_Subprogram (Iface_Prim)
9510 and then Is_Subprogram (Prim)
9511 and then Is_Dispatching_Operation (Iface_Prim)
9512 and then Is_Dispatching_Operation (Prim));
9514 pragma Assert (Is_Interface (Iface)
9515 or else (Present (Alias (Iface_Prim))
9518 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9520 if Prim = Iface_Prim
9521 or else not Is_Subprogram (Prim)
9522 or else Ekind (Prim) /= Ekind (Iface_Prim)
9523 or else not Is_Dispatching_Operation (Prim)
9524 or else Scope (Prim) /= Scope (Tagged_Type)
9526 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9527 or else not Primitive_Names_Match (Iface_Prim, Prim)
9531 -- The mode of the controlling formals must match
9533 elsif Present (Iface_Ctrl_F)
9534 and then Present (Prim_Ctrl_F)
9535 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9539 -- Case of a procedure, or a function whose result type matches the
9540 -- result type of the interface primitive, or a function that has no
9541 -- controlling result (I or access I).
9543 elsif Ekind (Iface_Prim) = E_Procedure
9544 or else Etype (Prim) = Etype (Iface_Prim)
9545 or else not Has_Controlling_Result (Prim)
9547 return Type_Conformant
9548 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9550 -- Case of a function returning an interface, or an access to one. Check
9551 -- that the return types correspond.
9553 elsif Implements_Interface (Typ, Iface) then
9554 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9556 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9561 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9562 Skip_Controlling_Formals => True);
9568 end Is_Interface_Conformant;
9570 ---------------------------------
9571 -- Is_Non_Overriding_Operation --
9572 ---------------------------------
9574 function Is_Non_Overriding_Operation
9575 (Prev_E : Entity_Id;
9576 New_E : Entity_Id) return Boolean
9580 G_Typ : Entity_Id := Empty;
9582 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9583 -- If F_Type is a derived type associated with a generic actual subtype,
9584 -- then return its Generic_Parent_Type attribute, else return Empty.
9586 function Types_Correspond
9587 (P_Type : Entity_Id;
9588 N_Type : Entity_Id) return Boolean;
9589 -- Returns true if and only if the types (or designated types in the
9590 -- case of anonymous access types) are the same or N_Type is derived
9591 -- directly or indirectly from P_Type.
9593 -----------------------------
9594 -- Get_Generic_Parent_Type --
9595 -----------------------------
9597 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9603 if Is_Derived_Type (F_Typ)
9604 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9606 -- The tree must be traversed to determine the parent subtype in
9607 -- the generic unit, which unfortunately isn't always available
9608 -- via semantic attributes. ??? (Note: The use of Original_Node
9609 -- is needed for cases where a full derived type has been
9612 -- If the parent type is a scalar type, the derivation creates
9613 -- an anonymous base type for it, and the source type is its
9616 if Is_Scalar_Type (F_Typ)
9617 and then not Comes_From_Source (F_Typ)
9621 (Original_Node (Parent (First_Subtype (F_Typ))));
9623 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9625 if Nkind (Defn) = N_Derived_Type_Definition then
9626 Indic := Subtype_Indication (Defn);
9628 if Nkind (Indic) = N_Subtype_Indication then
9629 G_Typ := Entity (Subtype_Mark (Indic));
9631 G_Typ := Entity (Indic);
9634 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9635 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9637 return Generic_Parent_Type (Parent (G_Typ));
9643 end Get_Generic_Parent_Type;
9645 ----------------------
9646 -- Types_Correspond --
9647 ----------------------
9649 function Types_Correspond
9650 (P_Type : Entity_Id;
9651 N_Type : Entity_Id) return Boolean
9653 Prev_Type : Entity_Id := Base_Type (P_Type);
9654 New_Type : Entity_Id := Base_Type (N_Type);
9657 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9658 Prev_Type := Designated_Type (Prev_Type);
9661 if Ekind (New_Type) = E_Anonymous_Access_Type then
9662 New_Type := Designated_Type (New_Type);
9665 if Prev_Type = New_Type then
9668 elsif not Is_Class_Wide_Type (New_Type) then
9669 while Etype (New_Type) /= New_Type loop
9670 New_Type := Etype (New_Type);
9672 if New_Type = Prev_Type then
9678 end Types_Correspond;
9680 -- Start of processing for Is_Non_Overriding_Operation
9683 -- In the case where both operations are implicit derived subprograms
9684 -- then neither overrides the other. This can only occur in certain
9685 -- obscure cases (e.g., derivation from homographs created in a generic
9688 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9691 elsif Ekind (Current_Scope) = E_Package
9692 and then Is_Generic_Instance (Current_Scope)
9693 and then In_Private_Part (Current_Scope)
9694 and then Comes_From_Source (New_E)
9696 -- We examine the formals and result type of the inherited operation,
9697 -- to determine whether their type is derived from (the instance of)
9698 -- a generic type. The first such formal or result type is the one
9701 Formal := First_Formal (Prev_E);
9703 while Present (Formal) loop
9704 F_Typ := Base_Type (Etype (Formal));
9706 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9707 F_Typ := Designated_Type (F_Typ);
9710 G_Typ := Get_Generic_Parent_Type (F_Typ);
9711 exit when Present (G_Typ);
9713 Next_Formal (Formal);
9716 -- If the function dispatches on result check the result type
9718 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9719 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9726 -- If the generic type is a private type, then the original operation
9727 -- was not overriding in the generic, because there was no primitive
9728 -- operation to override.
9730 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9731 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9732 N_Formal_Private_Type_Definition
9736 -- The generic parent type is the ancestor of a formal derived
9737 -- type declaration. We need to check whether it has a primitive
9738 -- operation that should be overridden by New_E in the generic.
9742 P_Formal : Entity_Id;
9743 N_Formal : Entity_Id;
9747 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9750 while Present (Prim_Elt) loop
9751 P_Prim := Node (Prim_Elt);
9753 if Chars (P_Prim) = Chars (New_E)
9754 and then Ekind (P_Prim) = Ekind (New_E)
9756 P_Formal := First_Formal (P_Prim);
9757 N_Formal := First_Formal (New_E);
9758 while Present (P_Formal) and then Present (N_Formal) loop
9759 P_Typ := Etype (P_Formal);
9760 N_Typ := Etype (N_Formal);
9762 if not Types_Correspond (P_Typ, N_Typ) then
9766 Next_Entity (P_Formal);
9767 Next_Entity (N_Formal);
9770 -- Found a matching primitive operation belonging to the
9771 -- formal ancestor type, so the new subprogram is
9775 and then No (N_Formal)
9776 and then (Ekind (New_E) /= E_Function
9779 (Etype (P_Prim), Etype (New_E)))
9785 Next_Elmt (Prim_Elt);
9788 -- If no match found, then the new subprogram does not override
9789 -- in the generic (nor in the instance).
9791 -- If the type in question is not abstract, and the subprogram
9792 -- is, this will be an error if the new operation is in the
9793 -- private part of the instance. Emit a warning now, which will
9794 -- make the subsequent error message easier to understand.
9796 if Present (F_Typ) and then not Is_Abstract_Type (F_Typ)
9797 and then Is_Abstract_Subprogram (Prev_E)
9798 and then In_Private_Part (Current_Scope)
9800 Error_Msg_Node_2 := F_Typ;
9802 ("private operation& in generic unit does not override "
9803 & "any primitive operation of& (RM 12.3 (18))??",
9813 end Is_Non_Overriding_Operation;
9815 -------------------------------------
9816 -- List_Inherited_Pre_Post_Aspects --
9817 -------------------------------------
9819 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9821 if Opt.List_Inherited_Aspects
9822 and then Is_Subprogram_Or_Generic_Subprogram (E)
9825 Subps : constant Subprogram_List := Inherited_Subprograms (E);
9830 for Index in Subps'Range loop
9831 Items := Contract (Subps (Index));
9833 if Present (Items) then
9834 Prag := Pre_Post_Conditions (Items);
9835 while Present (Prag) loop
9836 Error_Msg_Sloc := Sloc (Prag);
9838 if Class_Present (Prag)
9839 and then not Split_PPC (Prag)
9841 if Pragma_Name (Prag) = Name_Precondition then
9843 ("info: & inherits `Pre''Class` aspect from "
9847 ("info: & inherits `Post''Class` aspect from "
9852 Prag := Next_Pragma (Prag);
9858 end List_Inherited_Pre_Post_Aspects;
9860 ------------------------------
9861 -- Make_Inequality_Operator --
9862 ------------------------------
9864 -- S is the defining identifier of an equality operator. We build a
9865 -- subprogram declaration with the right signature. This operation is
9866 -- intrinsic, because it is always expanded as the negation of the
9867 -- call to the equality function.
9869 procedure Make_Inequality_Operator (S : Entity_Id) is
9870 Loc : constant Source_Ptr := Sloc (S);
9873 Op_Name : Entity_Id;
9875 FF : constant Entity_Id := First_Formal (S);
9876 NF : constant Entity_Id := Next_Formal (FF);
9879 -- Check that equality was properly defined, ignore call if not
9886 A : constant Entity_Id :=
9887 Make_Defining_Identifier (Sloc (FF),
9888 Chars => Chars (FF));
9890 B : constant Entity_Id :=
9891 Make_Defining_Identifier (Sloc (NF),
9892 Chars => Chars (NF));
9895 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9897 Formals := New_List (
9898 Make_Parameter_Specification (Loc,
9899 Defining_Identifier => A,
9901 New_Occurrence_Of (Etype (First_Formal (S)),
9902 Sloc (Etype (First_Formal (S))))),
9904 Make_Parameter_Specification (Loc,
9905 Defining_Identifier => B,
9907 New_Occurrence_Of (Etype (Next_Formal (First_Formal (S))),
9908 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9911 Make_Subprogram_Declaration (Loc,
9913 Make_Function_Specification (Loc,
9914 Defining_Unit_Name => Op_Name,
9915 Parameter_Specifications => Formals,
9916 Result_Definition =>
9917 New_Occurrence_Of (Standard_Boolean, Loc)));
9919 -- Insert inequality right after equality if it is explicit or after
9920 -- the derived type when implicit. These entities are created only
9921 -- for visibility purposes, and eventually replaced in the course
9922 -- of expansion, so they do not need to be attached to the tree and
9923 -- seen by the back-end. Keeping them internal also avoids spurious
9924 -- freezing problems. The declaration is inserted in the tree for
9925 -- analysis, and removed afterwards. If the equality operator comes
9926 -- from an explicit declaration, attach the inequality immediately
9927 -- after. Else the equality is inherited from a derived type
9928 -- declaration, so insert inequality after that declaration.
9930 if No (Alias (S)) then
9931 Insert_After (Unit_Declaration_Node (S), Decl);
9932 elsif Is_List_Member (Parent (S)) then
9933 Insert_After (Parent (S), Decl);
9935 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9938 Mark_Rewrite_Insertion (Decl);
9939 Set_Is_Intrinsic_Subprogram (Op_Name);
9942 Set_Has_Completion (Op_Name);
9943 Set_Corresponding_Equality (Op_Name, S);
9944 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9946 end Make_Inequality_Operator;
9948 ----------------------
9949 -- May_Need_Actuals --
9950 ----------------------
9952 procedure May_Need_Actuals (Fun : Entity_Id) is
9957 F := First_Formal (Fun);
9959 while Present (F) loop
9960 if No (Default_Value (F)) then
9968 Set_Needs_No_Actuals (Fun, B);
9969 end May_Need_Actuals;
9971 ---------------------
9972 -- Mode_Conformant --
9973 ---------------------
9975 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9978 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9980 end Mode_Conformant;
9982 ---------------------------
9983 -- New_Overloaded_Entity --
9984 ---------------------------
9986 procedure New_Overloaded_Entity
9988 Derived_Type : Entity_Id := Empty)
9990 Overridden_Subp : Entity_Id := Empty;
9991 -- Set if the current scope has an operation that is type-conformant
9992 -- with S, and becomes hidden by S.
9994 Is_Primitive_Subp : Boolean;
9995 -- Set to True if the new subprogram is primitive
9998 -- Entity that S overrides
10000 Prev_Vis : Entity_Id := Empty;
10001 -- Predecessor of E in Homonym chain
10003 procedure Check_For_Primitive_Subprogram
10004 (Is_Primitive : out Boolean;
10005 Is_Overriding : Boolean := False);
10006 -- If the subprogram being analyzed is a primitive operation of the type
10007 -- of a formal or result, set the Has_Primitive_Operations flag on the
10008 -- type, and set Is_Primitive to True (otherwise set to False). Set the
10009 -- corresponding flag on the entity itself for later use.
10011 function Has_Matching_Entry_Or_Subprogram (E : Entity_Id) return Boolean;
10012 -- True if a) E is a subprogram whose first formal is a concurrent type
10013 -- defined in the scope of E that has some entry or subprogram whose
10014 -- profile matches E, or b) E is an internally built dispatching
10015 -- subprogram of a protected type and there is a matching subprogram
10016 -- defined in the enclosing scope of the protected type, or c) E is
10017 -- an entry of a synchronized type and a matching procedure has been
10018 -- previously defined in the enclosing scope of the synchronized type.
10020 function Is_Private_Declaration (E : Entity_Id) return Boolean;
10021 -- Check that E is declared in the private part of the current package,
10022 -- or in the package body, where it may hide a previous declaration.
10023 -- We can't use In_Private_Part by itself because this flag is also
10024 -- set when freezing entities, so we must examine the place of the
10025 -- declaration in the tree, and recognize wrapper packages as well.
10027 function Is_Overriding_Alias
10028 (Old_E : Entity_Id;
10029 New_E : Entity_Id) return Boolean;
10030 -- Check whether new subprogram and old subprogram are both inherited
10031 -- from subprograms that have distinct dispatch table entries. This can
10032 -- occur with derivations from instances with accidental homonyms. The
10033 -- function is conservative given that the converse is only true within
10034 -- instances that contain accidental overloadings.
10036 procedure Report_Conflict (S : Entity_Id; E : Entity_Id);
10037 -- Report conflict between entities S and E
10039 ------------------------------------
10040 -- Check_For_Primitive_Subprogram --
10041 ------------------------------------
10043 procedure Check_For_Primitive_Subprogram
10044 (Is_Primitive : out Boolean;
10045 Is_Overriding : Boolean := False)
10047 Formal : Entity_Id;
10051 function Visible_Part_Type (T : Entity_Id) return Boolean;
10052 -- Returns true if T is declared in the visible part of the current
10053 -- package scope; otherwise returns false. Assumes that T is declared
10056 procedure Check_Private_Overriding (T : Entity_Id);
10057 -- Checks that if a primitive abstract subprogram of a visible
10058 -- abstract type is declared in a private part, then it must override
10059 -- an abstract subprogram declared in the visible part. Also checks
10060 -- that if a primitive function with a controlling result is declared
10061 -- in a private part, then it must override a function declared in
10062 -- the visible part.
10064 ------------------------------
10065 -- Check_Private_Overriding --
10066 ------------------------------
10068 procedure Check_Private_Overriding (T : Entity_Id) is
10069 function Overrides_Private_Part_Op return Boolean;
10070 -- This detects the special case where the overriding subprogram
10071 -- is overriding a subprogram that was declared in the same
10072 -- private part. That case is illegal by 3.9.3(10).
10074 function Overrides_Visible_Function
10075 (Partial_View : Entity_Id) return Boolean;
10076 -- True if S overrides a function in the visible part. The
10077 -- overridden function could be explicitly or implicitly declared.
10079 -------------------------------
10080 -- Overrides_Private_Part_Op --
10081 -------------------------------
10083 function Overrides_Private_Part_Op return Boolean is
10084 Over_Decl : constant Node_Id :=
10085 Unit_Declaration_Node (Overridden_Operation (S));
10086 Subp_Decl : constant Node_Id := Unit_Declaration_Node (S);
10089 pragma Assert (Is_Overriding);
10091 (Nkind (Over_Decl) = N_Abstract_Subprogram_Declaration);
10093 (Nkind (Subp_Decl) = N_Abstract_Subprogram_Declaration);
10095 return In_Same_List (Over_Decl, Subp_Decl);
10096 end Overrides_Private_Part_Op;
10098 --------------------------------
10099 -- Overrides_Visible_Function --
10100 --------------------------------
10102 function Overrides_Visible_Function
10103 (Partial_View : Entity_Id) return Boolean
10106 if not Is_Overriding or else not Has_Homonym (S) then
10110 if not Present (Partial_View) then
10114 -- Search through all the homonyms H of S in the current
10115 -- package spec, and return True if we find one that matches.
10116 -- Note that Parent (H) will be the declaration of the
10117 -- partial view of T for a match.
10120 H : Entity_Id := S;
10124 exit when not Present (H) or else Scope (H) /= Scope (S);
10128 N_Private_Extension_Declaration,
10129 N_Private_Type_Declaration)
10130 and then Defining_Identifier (Parent (H)) = Partial_View
10138 end Overrides_Visible_Function;
10140 -- Start of processing for Check_Private_Overriding
10143 if Is_Package_Or_Generic_Package (Current_Scope)
10144 and then In_Private_Part (Current_Scope)
10145 and then Visible_Part_Type (T)
10146 and then not In_Instance
10148 if Is_Abstract_Type (T)
10149 and then Is_Abstract_Subprogram (S)
10150 and then (not Is_Overriding
10151 or else not Is_Abstract_Subprogram (E)
10152 or else Overrides_Private_Part_Op)
10155 ("abstract subprograms must be visible (RM 3.9.3(10))!",
10158 elsif Ekind (S) = E_Function then
10160 Partial_View : constant Entity_Id :=
10161 Incomplete_Or_Partial_View (T);
10164 if not Overrides_Visible_Function (Partial_View) then
10166 -- Here, S is "function ... return T;" declared in
10167 -- the private part, not overriding some visible
10168 -- operation. That's illegal in the tagged case
10169 -- (but not if the private type is untagged).
10171 if ((Present (Partial_View)
10172 and then Is_Tagged_Type (Partial_View))
10173 or else (not Present (Partial_View)
10174 and then Is_Tagged_Type (T)))
10175 and then T = Base_Type (Etype (S))
10178 ("private function with tagged result must"
10179 & " override visible-part function", S);
10181 ("\move subprogram to the visible part"
10182 & " (RM 3.9.3(10))", S);
10184 -- AI05-0073: extend this test to the case of a
10185 -- function with a controlling access result.
10187 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
10188 and then Is_Tagged_Type (Designated_Type (Etype (S)))
10190 not Is_Class_Wide_Type
10191 (Designated_Type (Etype (S)))
10192 and then Ada_Version >= Ada_2012
10195 ("private function with controlling access "
10196 & "result must override visible-part function",
10199 ("\move subprogram to the visible part"
10200 & " (RM 3.9.3(10))", S);
10206 end Check_Private_Overriding;
10208 -----------------------
10209 -- Visible_Part_Type --
10210 -----------------------
10212 function Visible_Part_Type (T : Entity_Id) return Boolean is
10213 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
10216 -- If the entity is a private type, then it must be declared in a
10219 if Ekind (T) in Private_Kind then
10222 elsif Is_Type (T) and then Has_Private_Declaration (T) then
10225 elsif Is_List_Member (Declaration_Node (T))
10226 and then List_Containing (Declaration_Node (T)) =
10227 Visible_Declarations (Specification (P))
10234 end Visible_Part_Type;
10236 -- Start of processing for Check_For_Primitive_Subprogram
10239 Is_Primitive := False;
10241 if not Comes_From_Source (S) then
10244 -- If subprogram is at library level, it is not primitive operation
10246 elsif Current_Scope = Standard_Standard then
10249 elsif (Is_Package_Or_Generic_Package (Current_Scope)
10250 and then not In_Package_Body (Current_Scope))
10251 or else Is_Overriding
10253 -- For function, check return type
10255 if Ekind (S) = E_Function then
10256 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
10257 F_Typ := Designated_Type (Etype (S));
10259 F_Typ := Etype (S);
10262 B_Typ := Base_Type (F_Typ);
10264 if Scope (B_Typ) = Current_Scope
10265 and then not Is_Class_Wide_Type (B_Typ)
10266 and then not Is_Generic_Type (B_Typ)
10268 Is_Primitive := True;
10269 Set_Has_Primitive_Operations (B_Typ);
10270 Set_Is_Primitive (S);
10271 Check_Private_Overriding (B_Typ);
10273 -- The Ghost policy in effect at the point of declaration
10274 -- or a tagged type and a primitive operation must match
10275 -- (SPARK RM 6.9(16)).
10277 Check_Ghost_Primitive (S, B_Typ);
10281 -- For all subprograms, check formals
10283 Formal := First_Formal (S);
10284 while Present (Formal) loop
10285 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
10286 F_Typ := Designated_Type (Etype (Formal));
10288 F_Typ := Etype (Formal);
10291 B_Typ := Base_Type (F_Typ);
10293 if Ekind (B_Typ) = E_Access_Subtype then
10294 B_Typ := Base_Type (B_Typ);
10297 if Scope (B_Typ) = Current_Scope
10298 and then not Is_Class_Wide_Type (B_Typ)
10299 and then not Is_Generic_Type (B_Typ)
10301 Is_Primitive := True;
10302 Set_Is_Primitive (S);
10303 Set_Has_Primitive_Operations (B_Typ);
10304 Check_Private_Overriding (B_Typ);
10306 -- The Ghost policy in effect at the point of declaration
10307 -- of a tagged type and a primitive operation must match
10308 -- (SPARK RM 6.9(16)).
10310 Check_Ghost_Primitive (S, B_Typ);
10313 Next_Formal (Formal);
10316 -- Special case: An equality function can be redefined for a type
10317 -- occurring in a declarative part, and won't otherwise be treated as
10318 -- a primitive because it doesn't occur in a package spec and doesn't
10319 -- override an inherited subprogram. It's important that we mark it
10320 -- primitive so it can be returned by Collect_Primitive_Operations
10321 -- and be used in composing the equality operation of later types
10322 -- that have a component of the type.
10324 elsif Chars (S) = Name_Op_Eq
10325 and then Etype (S) = Standard_Boolean
10327 B_Typ := Base_Type (Etype (First_Formal (S)));
10329 if Scope (B_Typ) = Current_Scope
10331 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
10332 and then not Is_Limited_Type (B_Typ)
10334 Is_Primitive := True;
10335 Set_Is_Primitive (S);
10336 Set_Has_Primitive_Operations (B_Typ);
10337 Check_Private_Overriding (B_Typ);
10339 -- The Ghost policy in effect at the point of declaration of a
10340 -- tagged type and a primitive operation must match
10341 -- (SPARK RM 6.9(16)).
10343 Check_Ghost_Primitive (S, B_Typ);
10346 end Check_For_Primitive_Subprogram;
10348 --------------------------------------
10349 -- Has_Matching_Entry_Or_Subprogram --
10350 --------------------------------------
10352 function Has_Matching_Entry_Or_Subprogram
10353 (E : Entity_Id) return Boolean
10355 function Check_Conforming_Parameters
10356 (E1_Param : Node_Id;
10357 E2_Param : Node_Id) return Boolean;
10358 -- Starting from the given parameters, check that all the parameters
10359 -- of two entries or subprograms are subtype conformant. Used to skip
10360 -- the check on the controlling argument.
10362 function Matching_Entry_Or_Subprogram
10363 (Conc_Typ : Entity_Id;
10364 Subp : Entity_Id) return Entity_Id;
10365 -- Return the first entry or subprogram of the given concurrent type
10366 -- whose name matches the name of Subp and has a profile conformant
10367 -- with Subp; return Empty if not found.
10369 function Matching_Dispatching_Subprogram
10370 (Conc_Typ : Entity_Id;
10371 Ent : Entity_Id) return Entity_Id;
10372 -- Return the first dispatching primitive of Conc_Type defined in the
10373 -- enclosing scope of Conc_Type (i.e. before the full definition of
10374 -- this concurrent type) whose name matches the entry Ent and has a
10375 -- profile conformant with the profile of the corresponding (not yet
10376 -- built) dispatching primitive of Ent; return Empty if not found.
10378 function Matching_Original_Protected_Subprogram
10379 (Prot_Typ : Entity_Id;
10380 Subp : Entity_Id) return Entity_Id;
10381 -- Return the first subprogram defined in the enclosing scope of
10382 -- Prot_Typ (before the full definition of this protected type)
10383 -- whose name matches the original name of Subp and has a profile
10384 -- conformant with the profile of Subp; return Empty if not found.
10386 ---------------------------------
10387 -- Check_Conforming_Parameters --
10388 ---------------------------------
10390 function Check_Conforming_Parameters
10391 (E1_Param : Node_Id;
10392 E2_Param : Node_Id) return Boolean
10394 Param_E1 : Node_Id := E1_Param;
10395 Param_E2 : Node_Id := E2_Param;
10398 while Present (Param_E1) and then Present (Param_E2) loop
10399 if Ekind (Defining_Identifier (Param_E1)) /=
10400 Ekind (Defining_Identifier (Param_E2))
10403 (Find_Parameter_Type (Param_E1),
10404 Find_Parameter_Type (Param_E2),
10405 Subtype_Conformant)
10414 -- The candidate is not valid if one of the two lists contains
10415 -- more parameters than the other
10417 return No (Param_E1) and then No (Param_E2);
10418 end Check_Conforming_Parameters;
10420 ----------------------------------
10421 -- Matching_Entry_Or_Subprogram --
10422 ----------------------------------
10424 function Matching_Entry_Or_Subprogram
10425 (Conc_Typ : Entity_Id;
10426 Subp : Entity_Id) return Entity_Id
10431 E := First_Entity (Conc_Typ);
10432 while Present (E) loop
10433 if Chars (Subp) = Chars (E)
10434 and then (Ekind (E) = E_Entry or else Is_Subprogram (E))
10436 Check_Conforming_Parameters
10437 (First (Parameter_Specifications (Parent (E))),
10438 Next (First (Parameter_Specifications (Parent (Subp)))))
10447 end Matching_Entry_Or_Subprogram;
10449 -------------------------------------
10450 -- Matching_Dispatching_Subprogram --
10451 -------------------------------------
10453 function Matching_Dispatching_Subprogram
10454 (Conc_Typ : Entity_Id;
10455 Ent : Entity_Id) return Entity_Id
10460 -- Search for entities in the enclosing scope of this synchonized
10463 pragma Assert (Is_Concurrent_Type (Conc_Typ));
10464 Push_Scope (Scope (Conc_Typ));
10465 E := Current_Entity_In_Scope (Ent);
10468 while Present (E) loop
10469 if Scope (E) = Scope (Conc_Typ)
10470 and then Comes_From_Source (E)
10471 and then Ekind (E) = E_Procedure
10472 and then Present (First_Entity (E))
10473 and then Is_Controlling_Formal (First_Entity (E))
10474 and then Etype (First_Entity (E)) = Conc_Typ
10476 Check_Conforming_Parameters
10477 (First (Parameter_Specifications (Parent (Ent))),
10478 Next (First (Parameter_Specifications (Parent (E)))))
10487 end Matching_Dispatching_Subprogram;
10489 --------------------------------------------
10490 -- Matching_Original_Protected_Subprogram --
10491 --------------------------------------------
10493 function Matching_Original_Protected_Subprogram
10494 (Prot_Typ : Entity_Id;
10495 Subp : Entity_Id) return Entity_Id
10497 ICF : constant Boolean :=
10498 Is_Controlling_Formal (First_Entity (Subp));
10502 -- Temporarily decorate the first parameter of Subp as controlling
10503 -- formal, required to invoke Subtype_Conformant.
10505 Set_Is_Controlling_Formal (First_Entity (Subp));
10508 Current_Entity_In_Scope (Original_Protected_Subprogram (Subp));
10510 while Present (E) loop
10511 if Scope (E) = Scope (Prot_Typ)
10512 and then Comes_From_Source (E)
10513 and then Ekind (Subp) = Ekind (E)
10514 and then Present (First_Entity (E))
10515 and then Is_Controlling_Formal (First_Entity (E))
10516 and then Etype (First_Entity (E)) = Prot_Typ
10517 and then Subtype_Conformant (Subp, E,
10518 Skip_Controlling_Formals => True)
10520 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10527 Set_Is_Controlling_Formal (First_Entity (Subp), ICF);
10530 end Matching_Original_Protected_Subprogram;
10532 -- Start of processing for Has_Matching_Entry_Or_Subprogram
10535 -- Case 1: E is a subprogram whose first formal is a concurrent type
10536 -- defined in the scope of E that has an entry or subprogram whose
10537 -- profile matches E.
10539 if Comes_From_Source (E)
10540 and then Is_Subprogram (E)
10541 and then Present (First_Entity (E))
10542 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10545 Scope (Corresponding_Concurrent_Type
10546 (Etype (First_Entity (E))))
10549 (Matching_Entry_Or_Subprogram
10550 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10553 Report_Conflict (E,
10554 Matching_Entry_Or_Subprogram
10555 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10560 -- Case 2: E is an internally built dispatching subprogram of a
10561 -- protected type and there is a subprogram defined in the enclosing
10562 -- scope of the protected type that has the original name of E and
10563 -- its profile is conformant with the profile of E. We check the
10564 -- name of the original protected subprogram associated with E since
10565 -- the expander builds dispatching primitives of protected functions
10566 -- and procedures with other names (see Exp_Ch9.Build_Selected_Name).
10568 elsif not Comes_From_Source (E)
10569 and then Is_Subprogram (E)
10570 and then Present (First_Entity (E))
10571 and then Is_Concurrent_Record_Type (Etype (First_Entity (E)))
10572 and then Present (Original_Protected_Subprogram (E))
10575 (Matching_Original_Protected_Subprogram
10576 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10579 Report_Conflict (E,
10580 Matching_Original_Protected_Subprogram
10581 (Corresponding_Concurrent_Type (Etype (First_Entity (E))),
10585 -- Case 3: E is an entry of a synchronized type and a matching
10586 -- procedure has been previously defined in the enclosing scope
10587 -- of the synchronized type.
10589 elsif Comes_From_Source (E)
10590 and then Ekind (E) = E_Entry
10592 Present (Matching_Dispatching_Subprogram (Current_Scope, E))
10594 Report_Conflict (E,
10595 Matching_Dispatching_Subprogram (Current_Scope, E));
10600 end Has_Matching_Entry_Or_Subprogram;
10602 ----------------------------
10603 -- Is_Private_Declaration --
10604 ----------------------------
10606 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10607 Decl : constant Node_Id := Unit_Declaration_Node (E);
10608 Priv_Decls : List_Id;
10611 if Is_Package_Or_Generic_Package (Current_Scope)
10612 and then In_Private_Part (Current_Scope)
10615 Private_Declarations (Package_Specification (Current_Scope));
10617 return In_Package_Body (Current_Scope)
10619 (Is_List_Member (Decl)
10620 and then List_Containing (Decl) = Priv_Decls)
10621 or else (Nkind (Parent (Decl)) = N_Package_Specification
10623 Is_Compilation_Unit
10624 (Defining_Entity (Parent (Decl)))
10625 and then List_Containing (Parent (Parent (Decl))) =
10630 end Is_Private_Declaration;
10632 --------------------------
10633 -- Is_Overriding_Alias --
10634 --------------------------
10636 function Is_Overriding_Alias
10637 (Old_E : Entity_Id;
10638 New_E : Entity_Id) return Boolean
10640 AO : constant Entity_Id := Alias (Old_E);
10641 AN : constant Entity_Id := Alias (New_E);
10644 return Scope (AO) /= Scope (AN)
10645 or else No (DTC_Entity (AO))
10646 or else No (DTC_Entity (AN))
10647 or else DT_Position (AO) = DT_Position (AN);
10648 end Is_Overriding_Alias;
10650 ---------------------
10651 -- Report_Conflict --
10652 ---------------------
10654 procedure Report_Conflict (S : Entity_Id; E : Entity_Id) is
10656 Error_Msg_Sloc := Sloc (E);
10658 -- Generate message, with useful additional warning if in generic
10660 if Is_Generic_Unit (E) then
10661 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10662 Error_Msg_N ("\& conflicts with declaration#", S);
10664 Error_Msg_N ("& conflicts with declaration#", S);
10666 end Report_Conflict;
10668 -- Start of processing for New_Overloaded_Entity
10671 -- We need to look for an entity that S may override. This must be a
10672 -- homonym in the current scope, so we look for the first homonym of
10673 -- S in the current scope as the starting point for the search.
10675 E := Current_Entity_In_Scope (S);
10677 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10678 -- They are directly added to the list of primitive operations of
10679 -- Derived_Type, unless this is a rederivation in the private part
10680 -- of an operation that was already derived in the visible part of
10681 -- the current package.
10683 if Ada_Version >= Ada_2005
10684 and then Present (Derived_Type)
10685 and then Present (Alias (S))
10686 and then Is_Dispatching_Operation (Alias (S))
10687 and then Present (Find_Dispatching_Type (Alias (S)))
10688 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10690 -- For private types, when the full-view is processed we propagate to
10691 -- the full view the non-overridden entities whose attribute "alias"
10692 -- references an interface primitive. These entities were added by
10693 -- Derive_Subprograms to ensure that interface primitives are
10696 -- Inside_Freeze_Actions is non zero when S corresponds with an
10697 -- internal entity that links an interface primitive with its
10698 -- covering primitive through attribute Interface_Alias (see
10699 -- Add_Internal_Interface_Entities).
10701 if Inside_Freezing_Actions = 0
10702 and then Is_Package_Or_Generic_Package (Current_Scope)
10703 and then In_Private_Part (Current_Scope)
10704 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10705 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10706 and then Full_View (Defining_Identifier (Parent (E)))
10707 = Defining_Identifier (Parent (S))
10708 and then Alias (E) = Alias (S)
10710 Check_Operation_From_Private_View (S, E);
10711 Set_Is_Dispatching_Operation (S);
10716 Enter_Overloaded_Entity (S);
10717 Check_Dispatching_Operation (S, Empty);
10718 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10724 -- For synchronized types check conflicts of this entity with previously
10725 -- defined entities.
10727 if Ada_Version >= Ada_2005
10728 and then Has_Matching_Entry_Or_Subprogram (S)
10733 -- If there is no homonym then this is definitely not overriding
10736 Enter_Overloaded_Entity (S);
10737 Check_Dispatching_Operation (S, Empty);
10738 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10740 -- If subprogram has an explicit declaration, check whether it has an
10741 -- overriding indicator.
10743 if Comes_From_Source (S) then
10744 Check_Synchronized_Overriding (S, Overridden_Subp);
10746 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10747 -- it may have overridden some hidden inherited primitive. Update
10748 -- Overridden_Subp to avoid spurious errors when checking the
10749 -- overriding indicator.
10751 if Ada_Version >= Ada_2012
10752 and then No (Overridden_Subp)
10753 and then Is_Dispatching_Operation (S)
10754 and then Present (Overridden_Operation (S))
10756 Overridden_Subp := Overridden_Operation (S);
10759 Check_Overriding_Indicator
10760 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10762 -- The Ghost policy in effect at the point of declaration of a
10763 -- parent subprogram and an overriding subprogram must match
10764 -- (SPARK RM 6.9(17)).
10766 Check_Ghost_Overriding (S, Overridden_Subp);
10769 -- If there is a homonym that is not overloadable, then we have an
10770 -- error, except for the special cases checked explicitly below.
10772 elsif not Is_Overloadable (E) then
10774 -- Check for spurious conflict produced by a subprogram that has the
10775 -- same name as that of the enclosing generic package. The conflict
10776 -- occurs within an instance, between the subprogram and the renaming
10777 -- declaration for the package. After the subprogram, the package
10778 -- renaming declaration becomes hidden.
10780 if Ekind (E) = E_Package
10781 and then Present (Renamed_Object (E))
10782 and then Renamed_Object (E) = Current_Scope
10783 and then Nkind (Parent (Renamed_Object (E))) =
10784 N_Package_Specification
10785 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10788 Set_Is_Immediately_Visible (E, False);
10789 Enter_Overloaded_Entity (S);
10790 Set_Homonym (S, Homonym (E));
10791 Check_Dispatching_Operation (S, Empty);
10792 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10794 -- If the subprogram is implicit it is hidden by the previous
10795 -- declaration. However if it is dispatching, it must appear in the
10796 -- dispatch table anyway, because it can be dispatched to even if it
10797 -- cannot be called directly.
10799 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10800 Set_Scope (S, Current_Scope);
10802 if Is_Dispatching_Operation (Alias (S)) then
10803 Check_Dispatching_Operation (S, Empty);
10809 Report_Conflict (S, E);
10813 -- E exists and is overloadable
10816 Check_Synchronized_Overriding (S, Overridden_Subp);
10818 -- Loop through E and its homonyms to determine if any of them is
10819 -- the candidate for overriding by S.
10821 while Present (E) loop
10823 -- Definitely not interesting if not in the current scope
10825 if Scope (E) /= Current_Scope then
10828 -- A function can overload the name of an abstract state. The
10829 -- state can be viewed as a function with a profile that cannot
10830 -- be matched by anything.
10832 elsif Ekind (S) = E_Function
10833 and then Ekind (E) = E_Abstract_State
10835 Enter_Overloaded_Entity (S);
10838 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10839 -- procedures locate the internally generated spec. We enforce
10840 -- mode conformance since a tagged type may inherit from
10841 -- interfaces several null primitives which differ only in
10842 -- the mode of the formals.
10844 elsif not Comes_From_Source (S)
10845 and then Is_Null_Procedure (S)
10846 and then not Mode_Conformant (E, S)
10850 -- Check if we have type conformance
10852 elsif Type_Conformant (E, S) then
10854 -- If the old and new entities have the same profile and one
10855 -- is not the body of the other, then this is an error, unless
10856 -- one of them is implicitly declared.
10858 -- There are some cases when both can be implicit, for example
10859 -- when both a literal and a function that overrides it are
10860 -- inherited in a derivation, or when an inherited operation
10861 -- of a tagged full type overrides the inherited operation of
10862 -- a private extension. Ada 83 had a special rule for the
10863 -- literal case. In Ada 95, the later implicit operation hides
10864 -- the former, and the literal is always the former. In the
10865 -- odd case where both are derived operations declared at the
10866 -- same point, both operations should be declared, and in that
10867 -- case we bypass the following test and proceed to the next
10868 -- part. This can only occur for certain obscure cases in
10869 -- instances, when an operation on a type derived from a formal
10870 -- private type does not override a homograph inherited from
10871 -- the actual. In subsequent derivations of such a type, the
10872 -- DT positions of these operations remain distinct, if they
10875 if Present (Alias (S))
10876 and then (No (Alias (E))
10877 or else Comes_From_Source (E)
10878 or else Is_Abstract_Subprogram (S)
10880 (Is_Dispatching_Operation (E)
10881 and then Is_Overriding_Alias (E, S)))
10882 and then Ekind (E) /= E_Enumeration_Literal
10884 -- When an derived operation is overloaded it may be due to
10885 -- the fact that the full view of a private extension
10886 -- re-inherits. It has to be dealt with.
10888 if Is_Package_Or_Generic_Package (Current_Scope)
10889 and then In_Private_Part (Current_Scope)
10891 Check_Operation_From_Private_View (S, E);
10894 -- In any case the implicit operation remains hidden by the
10895 -- existing declaration, which is overriding. Indicate that
10896 -- E overrides the operation from which S is inherited.
10898 if Present (Alias (S)) then
10899 Set_Overridden_Operation (E, Alias (S));
10900 Inherit_Subprogram_Contract (E, Alias (S));
10903 Set_Overridden_Operation (E, S);
10904 Inherit_Subprogram_Contract (E, S);
10907 if Comes_From_Source (E) then
10908 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10910 -- The Ghost policy in effect at the point of declaration
10911 -- of a parent subprogram and an overriding subprogram
10912 -- must match (SPARK RM 6.9(17)).
10914 Check_Ghost_Overriding (E, S);
10919 -- Within an instance, the renaming declarations for actual
10920 -- subprograms may become ambiguous, but they do not hide each
10923 elsif Ekind (E) /= E_Entry
10924 and then not Comes_From_Source (E)
10925 and then not Is_Generic_Instance (E)
10926 and then (Present (Alias (E))
10927 or else Is_Intrinsic_Subprogram (E))
10928 and then (not In_Instance
10929 or else No (Parent (E))
10930 or else Nkind (Unit_Declaration_Node (E)) /=
10931 N_Subprogram_Renaming_Declaration)
10933 -- A subprogram child unit is not allowed to override an
10934 -- inherited subprogram (10.1.1(20)).
10936 if Is_Child_Unit (S) then
10938 ("child unit overrides inherited subprogram in parent",
10943 if Is_Non_Overriding_Operation (E, S) then
10944 Enter_Overloaded_Entity (S);
10946 if No (Derived_Type)
10947 or else Is_Tagged_Type (Derived_Type)
10949 Check_Dispatching_Operation (S, Empty);
10955 -- E is a derived operation or an internal operator which
10956 -- is being overridden. Remove E from further visibility.
10957 -- Furthermore, if E is a dispatching operation, it must be
10958 -- replaced in the list of primitive operations of its type
10959 -- (see Override_Dispatching_Operation).
10961 Overridden_Subp := E;
10967 Prev := First_Entity (Current_Scope);
10968 while Present (Prev) and then Next_Entity (Prev) /= E loop
10969 Next_Entity (Prev);
10972 -- It is possible for E to be in the current scope and
10973 -- yet not in the entity chain. This can only occur in a
10974 -- generic context where E is an implicit concatenation
10975 -- in the formal part, because in a generic body the
10976 -- entity chain starts with the formals.
10978 -- In GNATprove mode, a wrapper for an operation with
10979 -- axiomatization may be a homonym of another declaration
10980 -- for an actual subprogram (needs refinement ???).
10984 and then GNATprove_Mode
10986 Nkind (Original_Node (Unit_Declaration_Node (S))) =
10987 N_Subprogram_Renaming_Declaration
10991 pragma Assert (Chars (E) = Name_Op_Concat);
10996 -- E must be removed both from the entity_list of the
10997 -- current scope, and from the visibility chain.
10999 if Debug_Flag_E then
11000 Write_Str ("Override implicit operation ");
11001 Write_Int (Int (E));
11005 -- If E is a predefined concatenation, it stands for four
11006 -- different operations. As a result, a single explicit
11007 -- declaration does not hide it. In a possible ambiguous
11008 -- situation, Disambiguate chooses the user-defined op,
11009 -- so it is correct to retain the previous internal one.
11011 if Chars (E) /= Name_Op_Concat
11012 or else Ekind (E) /= E_Operator
11014 -- For nondispatching derived operations that are
11015 -- overridden by a subprogram declared in the private
11016 -- part of a package, we retain the derived subprogram
11017 -- but mark it as not immediately visible. If the
11018 -- derived operation was declared in the visible part
11019 -- then this ensures that it will still be visible
11020 -- outside the package with the proper signature
11021 -- (calls from outside must also be directed to this
11022 -- version rather than the overriding one, unlike the
11023 -- dispatching case). Calls from inside the package
11024 -- will still resolve to the overriding subprogram
11025 -- since the derived one is marked as not visible
11026 -- within the package.
11028 -- If the private operation is dispatching, we achieve
11029 -- the overriding by keeping the implicit operation
11030 -- but setting its alias to be the overriding one. In
11031 -- this fashion the proper body is executed in all
11032 -- cases, but the original signature is used outside
11035 -- If the overriding is not in the private part, we
11036 -- remove the implicit operation altogether.
11038 if Is_Private_Declaration (S) then
11039 if not Is_Dispatching_Operation (E) then
11040 Set_Is_Immediately_Visible (E, False);
11042 -- Work done in Override_Dispatching_Operation,
11043 -- so nothing else needs to be done here.
11049 -- Find predecessor of E in Homonym chain
11051 if E = Current_Entity (E) then
11054 Prev_Vis := Current_Entity (E);
11055 while Homonym (Prev_Vis) /= E loop
11056 Prev_Vis := Homonym (Prev_Vis);
11060 if Prev_Vis /= Empty then
11062 -- Skip E in the visibility chain
11064 Set_Homonym (Prev_Vis, Homonym (E));
11067 Set_Name_Entity_Id (Chars (E), Homonym (E));
11070 Set_Next_Entity (Prev, Next_Entity (E));
11072 if No (Next_Entity (Prev)) then
11073 Set_Last_Entity (Current_Scope, Prev);
11078 Enter_Overloaded_Entity (S);
11080 -- For entities generated by Derive_Subprograms the
11081 -- overridden operation is the inherited primitive
11082 -- (which is available through the attribute alias).
11084 if not (Comes_From_Source (E))
11085 and then Is_Dispatching_Operation (E)
11086 and then Find_Dispatching_Type (E) =
11087 Find_Dispatching_Type (S)
11088 and then Present (Alias (E))
11089 and then Comes_From_Source (Alias (E))
11091 Set_Overridden_Operation (S, Alias (E));
11092 Inherit_Subprogram_Contract (S, Alias (E));
11094 -- Normal case of setting entity as overridden
11096 -- Note: Static_Initialization and Overridden_Operation
11097 -- attributes use the same field in subprogram entities.
11098 -- Static_Initialization is only defined for internal
11099 -- initialization procedures, where Overridden_Operation
11100 -- is irrelevant. Therefore the setting of this attribute
11101 -- must check whether the target is an init_proc.
11103 elsif not Is_Init_Proc (S) then
11104 Set_Overridden_Operation (S, E);
11105 Inherit_Subprogram_Contract (S, E);
11108 Check_Overriding_Indicator (S, E, Is_Primitive => True);
11110 -- The Ghost policy in effect at the point of declaration
11111 -- of a parent subprogram and an overriding subprogram
11112 -- must match (SPARK RM 6.9(17)).
11114 Check_Ghost_Overriding (S, E);
11116 -- If S is a user-defined subprogram or a null procedure
11117 -- expanded to override an inherited null procedure, or a
11118 -- predefined dispatching primitive then indicate that E
11119 -- overrides the operation from which S is inherited.
11121 if Comes_From_Source (S)
11123 (Present (Parent (S))
11125 Nkind (Parent (S)) = N_Procedure_Specification
11127 Null_Present (Parent (S)))
11129 (Present (Alias (E))
11131 Is_Predefined_Dispatching_Operation (Alias (E)))
11133 if Present (Alias (E)) then
11134 Set_Overridden_Operation (S, Alias (E));
11135 Inherit_Subprogram_Contract (S, Alias (E));
11139 if Is_Dispatching_Operation (E) then
11141 -- An overriding dispatching subprogram inherits the
11142 -- convention of the overridden subprogram (AI-117).
11144 Set_Convention (S, Convention (E));
11145 Check_Dispatching_Operation (S, E);
11148 Check_Dispatching_Operation (S, Empty);
11151 Check_For_Primitive_Subprogram
11152 (Is_Primitive_Subp, Is_Overriding => True);
11153 goto Check_Inequality;
11156 -- Apparent redeclarations in instances can occur when two
11157 -- formal types get the same actual type. The subprograms in
11158 -- in the instance are legal, even if not callable from the
11159 -- outside. Calls from within are disambiguated elsewhere.
11160 -- For dispatching operations in the visible part, the usual
11161 -- rules apply, and operations with the same profile are not
11162 -- legal (B830001).
11164 elsif (In_Instance_Visible_Part
11165 and then not Is_Dispatching_Operation (E))
11166 or else In_Instance_Not_Visible
11170 -- Here we have a real error (identical profile)
11173 Error_Msg_Sloc := Sloc (E);
11175 -- Avoid cascaded errors if the entity appears in
11176 -- subsequent calls.
11178 Set_Scope (S, Current_Scope);
11180 -- Generate error, with extra useful warning for the case
11181 -- of a generic instance with no completion.
11183 if Is_Generic_Instance (S)
11184 and then not Has_Completion (E)
11187 ("instantiation cannot provide body for&", S);
11188 Error_Msg_N ("\& conflicts with declaration#", S);
11190 Error_Msg_N ("& conflicts with declaration#", S);
11197 -- If one subprogram has an access parameter and the other
11198 -- a parameter of an access type, calls to either might be
11199 -- ambiguous. Verify that parameters match except for the
11200 -- access parameter.
11202 if May_Hide_Profile then
11208 F1 := First_Formal (S);
11209 F2 := First_Formal (E);
11210 while Present (F1) and then Present (F2) loop
11211 if Is_Access_Type (Etype (F1)) then
11212 if not Is_Access_Type (Etype (F2))
11213 or else not Conforming_Types
11214 (Designated_Type (Etype (F1)),
11215 Designated_Type (Etype (F2)),
11218 May_Hide_Profile := False;
11222 not Conforming_Types
11223 (Etype (F1), Etype (F2), Type_Conformant)
11225 May_Hide_Profile := False;
11232 if May_Hide_Profile
11236 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
11245 -- On exit, we know that S is a new entity
11247 Enter_Overloaded_Entity (S);
11248 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
11249 Check_Overriding_Indicator
11250 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
11252 -- The Ghost policy in effect at the point of declaration of a parent
11253 -- subprogram and an overriding subprogram must match
11254 -- (SPARK RM 6.9(17)).
11256 Check_Ghost_Overriding (S, Overridden_Subp);
11258 -- Overloading is not allowed in SPARK, except for operators
11260 if Nkind (S) /= N_Defining_Operator_Symbol then
11261 Error_Msg_Sloc := Sloc (Homonym (S));
11262 Check_SPARK_05_Restriction
11263 ("overloading not allowed with entity#", S);
11266 -- If S is a derived operation for an untagged type then by
11267 -- definition it's not a dispatching operation (even if the parent
11268 -- operation was dispatching), so Check_Dispatching_Operation is not
11269 -- called in that case.
11271 if No (Derived_Type)
11272 or else Is_Tagged_Type (Derived_Type)
11274 Check_Dispatching_Operation (S, Empty);
11278 -- If this is a user-defined equality operator that is not a derived
11279 -- subprogram, create the corresponding inequality. If the operation is
11280 -- dispatching, the expansion is done elsewhere, and we do not create
11281 -- an explicit inequality operation.
11283 <<Check_Inequality>>
11284 if Chars (S) = Name_Op_Eq
11285 and then Etype (S) = Standard_Boolean
11286 and then Present (Parent (S))
11287 and then not Is_Dispatching_Operation (S)
11289 Make_Inequality_Operator (S);
11290 Check_Untagged_Equality (S);
11292 end New_Overloaded_Entity;
11294 ---------------------
11295 -- Process_Formals --
11296 ---------------------
11298 procedure Process_Formals
11300 Related_Nod : Node_Id)
11302 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean;
11303 -- Determine whether an access type designates a type coming from a
11306 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
11307 -- Check whether the default has a class-wide type. After analysis the
11308 -- default has the type of the formal, so we must also check explicitly
11309 -- for an access attribute.
11311 ----------------------------------
11312 -- Designates_From_Limited_With --
11313 ----------------------------------
11315 function Designates_From_Limited_With (Typ : Entity_Id) return Boolean is
11316 Desig : Entity_Id := Typ;
11319 if Is_Access_Type (Desig) then
11320 Desig := Directly_Designated_Type (Desig);
11323 if Is_Class_Wide_Type (Desig) then
11324 Desig := Root_Type (Desig);
11328 Ekind (Desig) = E_Incomplete_Type
11329 and then From_Limited_With (Desig);
11330 end Designates_From_Limited_With;
11332 ---------------------------
11333 -- Is_Class_Wide_Default --
11334 ---------------------------
11336 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
11338 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
11339 or else (Nkind (D) = N_Attribute_Reference
11340 and then Attribute_Name (D) = Name_Access
11341 and then Is_Class_Wide_Type (Etype (Prefix (D))));
11342 end Is_Class_Wide_Default;
11346 Context : constant Node_Id := Parent (Parent (T));
11348 Formal : Entity_Id;
11349 Formal_Type : Entity_Id;
11350 Param_Spec : Node_Id;
11353 Num_Out_Params : Nat := 0;
11354 First_Out_Param : Entity_Id := Empty;
11355 -- Used for setting Is_Only_Out_Parameter
11357 -- Start of processing for Process_Formals
11360 -- In order to prevent premature use of the formals in the same formal
11361 -- part, the Ekind is left undefined until all default expressions are
11362 -- analyzed. The Ekind is established in a separate loop at the end.
11364 Param_Spec := First (T);
11365 while Present (Param_Spec) loop
11366 Formal := Defining_Identifier (Param_Spec);
11367 Set_Never_Set_In_Source (Formal, True);
11368 Enter_Name (Formal);
11370 -- Case of ordinary parameters
11372 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
11373 Find_Type (Parameter_Type (Param_Spec));
11374 Ptype := Parameter_Type (Param_Spec);
11376 if Ptype = Error then
11380 Formal_Type := Entity (Ptype);
11382 if Is_Incomplete_Type (Formal_Type)
11384 (Is_Class_Wide_Type (Formal_Type)
11385 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
11387 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
11388 -- primitive operations, as long as their completion is
11389 -- in the same declarative part. If in the private part
11390 -- this means that the type cannot be a Taft-amendment type.
11391 -- Check is done on package exit. For access to subprograms,
11392 -- the use is legal for Taft-amendment types.
11394 -- Ada 2012: tagged incomplete types are allowed as generic
11395 -- formal types. They do not introduce dependencies and the
11396 -- corresponding generic subprogram does not have a delayed
11397 -- freeze, because it does not need a freeze node. However,
11398 -- it is still the case that untagged incomplete types cannot
11399 -- be Taft-amendment types and must be completed in private
11400 -- part, so the subprogram must appear in the list of private
11401 -- dependents of the type.
11403 if Is_Tagged_Type (Formal_Type)
11404 or else (Ada_Version >= Ada_2012
11405 and then not From_Limited_With (Formal_Type)
11406 and then not Is_Generic_Type (Formal_Type))
11408 if Ekind (Scope (Current_Scope)) = E_Package
11409 and then not Is_Generic_Type (Formal_Type)
11410 and then not Is_Class_Wide_Type (Formal_Type)
11413 (Parent (T), N_Access_Function_Definition,
11414 N_Access_Procedure_Definition)
11416 Append_Elmt (Current_Scope,
11417 Private_Dependents (Base_Type (Formal_Type)));
11419 -- Freezing is delayed to ensure that Register_Prim
11420 -- will get called for this operation, which is needed
11421 -- in cases where static dispatch tables aren't built.
11422 -- (Note that the same is done for controlling access
11423 -- parameter cases in function Access_Definition.)
11425 if not Is_Thunk (Current_Scope) then
11426 Set_Has_Delayed_Freeze (Current_Scope);
11431 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11432 N_Access_Procedure_Definition)
11434 -- AI05-0151: Tagged incomplete types are allowed in all
11435 -- formal parts. Untagged incomplete types are not allowed
11436 -- in bodies. Limited views of either kind are not allowed
11437 -- if there is no place at which the non-limited view can
11438 -- become available.
11440 -- Incomplete formal untagged types are not allowed in
11441 -- subprogram bodies (but are legal in their declarations).
11442 -- This excludes bodies created for null procedures, which
11443 -- are basic declarations.
11445 if Is_Generic_Type (Formal_Type)
11446 and then not Is_Tagged_Type (Formal_Type)
11447 and then Nkind (Parent (Related_Nod)) = N_Subprogram_Body
11450 ("invalid use of formal incomplete type", Param_Spec);
11452 elsif Ada_Version >= Ada_2012 then
11453 if Is_Tagged_Type (Formal_Type)
11454 and then (not From_Limited_With (Formal_Type)
11455 or else not In_Package_Body)
11459 elsif Nkind_In (Context, N_Accept_Statement,
11460 N_Accept_Alternative,
11462 or else (Nkind (Context) = N_Subprogram_Body
11463 and then Comes_From_Source (Context))
11466 ("invalid use of untagged incomplete type &",
11467 Ptype, Formal_Type);
11472 ("invalid use of incomplete type&",
11473 Param_Spec, Formal_Type);
11475 -- Further checks on the legality of incomplete types
11476 -- in formal parts are delayed until the freeze point
11477 -- of the enclosing subprogram or access to subprogram.
11481 elsif Ekind (Formal_Type) = E_Void then
11483 ("premature use of&",
11484 Parameter_Type (Param_Spec), Formal_Type);
11487 -- Ada 2012 (AI-142): Handle aliased parameters
11489 if Ada_Version >= Ada_2012
11490 and then Aliased_Present (Param_Spec)
11492 Set_Is_Aliased (Formal);
11495 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11496 -- declaration corresponding to the null-excluding type of the
11497 -- formal in the enclosing scope. Finally, replace the parameter
11498 -- type of the formal with the internal subtype.
11500 if Ada_Version >= Ada_2005
11501 and then Null_Exclusion_Present (Param_Spec)
11503 if not Is_Access_Type (Formal_Type) then
11505 ("`NOT NULL` allowed only for an access type", Param_Spec);
11508 if Can_Never_Be_Null (Formal_Type)
11509 and then Comes_From_Source (Related_Nod)
11512 ("`NOT NULL` not allowed (& already excludes null)",
11513 Param_Spec, Formal_Type);
11517 Create_Null_Excluding_Itype
11519 Related_Nod => Related_Nod,
11520 Scope_Id => Scope (Current_Scope));
11522 -- If the designated type of the itype is an itype that is
11523 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11524 -- on the access subtype, to prevent order-of-elaboration
11525 -- issues in the backend.
11528 -- type T is access procedure;
11529 -- procedure Op (O : not null T);
11531 if Is_Itype (Directly_Designated_Type (Formal_Type))
11533 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11535 Set_Has_Delayed_Freeze (Formal_Type);
11540 -- An access formal type
11544 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11546 -- No need to continue if we already notified errors
11548 if not Present (Formal_Type) then
11552 -- Ada 2005 (AI-254)
11555 AD : constant Node_Id :=
11556 Access_To_Subprogram_Definition
11557 (Parameter_Type (Param_Spec));
11559 if Present (AD) and then Protected_Present (AD) then
11561 Replace_Anonymous_Access_To_Protected_Subprogram
11567 Set_Etype (Formal, Formal_Type);
11569 -- Deal with default expression if present
11571 Default := Expression (Param_Spec);
11573 if Present (Default) then
11574 Check_SPARK_05_Restriction
11575 ("default expression is not allowed", Default);
11577 if Out_Present (Param_Spec) then
11579 ("default initialization only allowed for IN parameters",
11583 -- Do the special preanalysis of the expression (see section on
11584 -- "Handling of Default Expressions" in the spec of package Sem).
11586 Preanalyze_Spec_Expression (Default, Formal_Type);
11588 -- An access to constant cannot be the default for
11589 -- an access parameter that is an access to variable.
11591 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11592 and then not Is_Access_Constant (Formal_Type)
11593 and then Is_Access_Type (Etype (Default))
11594 and then Is_Access_Constant (Etype (Default))
11597 ("formal that is access to variable cannot be initialized "
11598 & "with an access-to-constant expression", Default);
11601 -- Check that the designated type of an access parameter's default
11602 -- is not a class-wide type unless the parameter's designated type
11603 -- is also class-wide.
11605 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11606 and then not Designates_From_Limited_With (Formal_Type)
11607 and then Is_Class_Wide_Default (Default)
11608 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11611 ("access to class-wide expression not allowed here", Default);
11614 -- Check incorrect use of dynamically tagged expressions
11616 if Is_Tagged_Type (Formal_Type) then
11617 Check_Dynamically_Tagged_Expression
11619 Typ => Formal_Type,
11620 Related_Nod => Default);
11624 -- Ada 2005 (AI-231): Static checks
11626 if Ada_Version >= Ada_2005
11627 and then Is_Access_Type (Etype (Formal))
11628 and then Can_Never_Be_Null (Etype (Formal))
11630 Null_Exclusion_Static_Checks (Param_Spec);
11633 -- The following checks are relevant only when SPARK_Mode is on as
11634 -- these are not standard Ada legality rules.
11636 if SPARK_Mode = On then
11637 if Ekind_In (Scope (Formal), E_Function, E_Generic_Function) then
11639 -- A function cannot have a parameter of mode IN OUT or OUT
11642 if Ekind_In (Formal, E_In_Out_Parameter, E_Out_Parameter) then
11644 ("function cannot have parameter of mode `OUT` or "
11645 & "`IN OUT`", Formal);
11648 -- A procedure cannot have an effectively volatile formal
11649 -- parameter of mode IN because it behaves as a constant
11650 -- (SPARK RM 7.1.3(6)). -- ??? maybe 7.1.3(4)
11652 elsif Ekind (Scope (Formal)) = E_Procedure
11653 and then Ekind (Formal) = E_In_Parameter
11654 and then Is_Effectively_Volatile (Formal)
11657 ("formal parameter of mode `IN` cannot be volatile", Formal);
11665 -- If this is the formal part of a function specification, analyze the
11666 -- subtype mark in the context where the formals are visible but not
11667 -- yet usable, and may hide outer homographs.
11669 if Nkind (Related_Nod) = N_Function_Specification then
11670 Analyze_Return_Type (Related_Nod);
11673 -- Now set the kind (mode) of each formal
11675 Param_Spec := First (T);
11676 while Present (Param_Spec) loop
11677 Formal := Defining_Identifier (Param_Spec);
11678 Set_Formal_Mode (Formal);
11680 if Ekind (Formal) = E_In_Parameter then
11681 Set_Default_Value (Formal, Expression (Param_Spec));
11683 if Present (Expression (Param_Spec)) then
11684 Default := Expression (Param_Spec);
11686 if Is_Scalar_Type (Etype (Default)) then
11687 if Nkind (Parameter_Type (Param_Spec)) /=
11688 N_Access_Definition
11690 Formal_Type := Entity (Parameter_Type (Param_Spec));
11694 (Related_Nod, Parameter_Type (Param_Spec));
11697 Apply_Scalar_Range_Check (Default, Formal_Type);
11701 elsif Ekind (Formal) = E_Out_Parameter then
11702 Num_Out_Params := Num_Out_Params + 1;
11704 if Num_Out_Params = 1 then
11705 First_Out_Param := Formal;
11708 elsif Ekind (Formal) = E_In_Out_Parameter then
11709 Num_Out_Params := Num_Out_Params + 1;
11712 -- Skip remaining processing if formal type was in error
11714 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11715 goto Next_Parameter;
11718 -- Force call by reference if aliased
11721 Conv : constant Convention_Id := Convention (Etype (Formal));
11723 if Is_Aliased (Formal) then
11724 Set_Mechanism (Formal, By_Reference);
11726 -- Warn if user asked this to be passed by copy
11728 if Conv = Convention_Ada_Pass_By_Copy then
11730 ("cannot pass aliased parameter & by copy??", Formal);
11733 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11735 elsif Conv = Convention_Ada_Pass_By_Copy then
11736 Set_Mechanism (Formal, By_Copy);
11738 elsif Conv = Convention_Ada_Pass_By_Reference then
11739 Set_Mechanism (Formal, By_Reference);
11747 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11748 Set_Is_Only_Out_Parameter (First_Out_Param);
11750 end Process_Formals;
11752 ----------------------------
11753 -- Reference_Body_Formals --
11754 ----------------------------
11756 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11761 if Error_Posted (Spec) then
11765 -- Iterate over both lists. They may be of different lengths if the two
11766 -- specs are not conformant.
11768 Fs := First_Formal (Spec);
11769 Fb := First_Formal (Bod);
11770 while Present (Fs) and then Present (Fb) loop
11771 Generate_Reference (Fs, Fb, 'b');
11773 if Style_Check then
11774 Style.Check_Identifier (Fb, Fs);
11777 Set_Spec_Entity (Fb, Fs);
11778 Set_Referenced (Fs, False);
11782 end Reference_Body_Formals;
11784 -------------------------
11785 -- Set_Actual_Subtypes --
11786 -------------------------
11788 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11790 Formal : Entity_Id;
11792 First_Stmt : Node_Id := Empty;
11793 AS_Needed : Boolean;
11796 -- If this is an empty initialization procedure, no need to create
11797 -- actual subtypes (small optimization).
11799 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11802 -- Within a predicate function we do not want to generate local
11803 -- subtypes that may generate nested predicate functions.
11805 elsif Is_Subprogram (Subp) and then Is_Predicate_Function (Subp) then
11809 -- The subtype declarations may freeze the formals. The body generated
11810 -- for an expression function is not a freeze point, so do not emit
11811 -- these declarations (small loss of efficiency in rare cases).
11813 if Nkind (N) = N_Subprogram_Body
11814 and then Was_Expression_Function (N)
11819 Formal := First_Formal (Subp);
11820 while Present (Formal) loop
11821 T := Etype (Formal);
11823 -- We never need an actual subtype for a constrained formal
11825 if Is_Constrained (T) then
11826 AS_Needed := False;
11828 -- If we have unknown discriminants, then we do not need an actual
11829 -- subtype, or more accurately we cannot figure it out. Note that
11830 -- all class-wide types have unknown discriminants.
11832 elsif Has_Unknown_Discriminants (T) then
11833 AS_Needed := False;
11835 -- At this stage we have an unconstrained type that may need an
11836 -- actual subtype. For sure the actual subtype is needed if we have
11837 -- an unconstrained array type. However, in an instance, the type
11838 -- may appear as a subtype of the full view, while the actual is
11839 -- in fact private (in which case no actual subtype is needed) so
11840 -- check the kind of the base type.
11842 elsif Is_Array_Type (Base_Type (T)) then
11845 -- The only other case needing an actual subtype is an unconstrained
11846 -- record type which is an IN parameter (we cannot generate actual
11847 -- subtypes for the OUT or IN OUT case, since an assignment can
11848 -- change the discriminant values. However we exclude the case of
11849 -- initialization procedures, since discriminants are handled very
11850 -- specially in this context, see the section entitled "Handling of
11851 -- Discriminants" in Einfo.
11853 -- We also exclude the case of Discrim_SO_Functions (functions used
11854 -- in front-end layout mode for size/offset values), since in such
11855 -- functions only discriminants are referenced, and not only are such
11856 -- subtypes not needed, but they cannot always be generated, because
11857 -- of order of elaboration issues.
11859 elsif Is_Record_Type (T)
11860 and then Ekind (Formal) = E_In_Parameter
11861 and then Chars (Formal) /= Name_uInit
11862 and then not Is_Unchecked_Union (T)
11863 and then not Is_Discrim_SO_Function (Subp)
11867 -- All other cases do not need an actual subtype
11870 AS_Needed := False;
11873 -- Generate actual subtypes for unconstrained arrays and
11874 -- unconstrained discriminated records.
11877 if Nkind (N) = N_Accept_Statement then
11879 -- If expansion is active, the formal is replaced by a local
11880 -- variable that renames the corresponding entry of the
11881 -- parameter block, and it is this local variable that may
11882 -- require an actual subtype.
11884 if Expander_Active then
11885 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11887 Decl := Build_Actual_Subtype (T, Formal);
11890 if Present (Handled_Statement_Sequence (N)) then
11892 First (Statements (Handled_Statement_Sequence (N)));
11893 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11894 Mark_Rewrite_Insertion (Decl);
11896 -- If the accept statement has no body, there will be no
11897 -- reference to the actuals, so no need to compute actual
11904 Decl := Build_Actual_Subtype (T, Formal);
11905 Prepend (Decl, Declarations (N));
11906 Mark_Rewrite_Insertion (Decl);
11909 -- The declaration uses the bounds of an existing object, and
11910 -- therefore needs no constraint checks.
11912 Analyze (Decl, Suppress => All_Checks);
11913 Set_Is_Actual_Subtype (Defining_Identifier (Decl));
11915 -- We need to freeze manually the generated type when it is
11916 -- inserted anywhere else than in a declarative part.
11918 if Present (First_Stmt) then
11919 Insert_List_Before_And_Analyze (First_Stmt,
11920 Freeze_Entity (Defining_Identifier (Decl), N));
11922 -- Ditto if the type has a dynamic predicate, because the
11923 -- generated function will mention the actual subtype. The
11924 -- predicate may come from an explicit aspect of be inherited.
11926 elsif Has_Predicates (T) then
11927 Insert_List_Before_And_Analyze (Decl,
11928 Freeze_Entity (Defining_Identifier (Decl), N));
11931 if Nkind (N) = N_Accept_Statement
11932 and then Expander_Active
11934 Set_Actual_Subtype (Renamed_Object (Formal),
11935 Defining_Identifier (Decl));
11937 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11941 Next_Formal (Formal);
11943 end Set_Actual_Subtypes;
11945 ---------------------
11946 -- Set_Formal_Mode --
11947 ---------------------
11949 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11950 Spec : constant Node_Id := Parent (Formal_Id);
11951 Id : constant Entity_Id := Scope (Formal_Id);
11954 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11955 -- since we ensure that corresponding actuals are always valid at the
11956 -- point of the call.
11958 if Out_Present (Spec) then
11959 if Ekind_In (Id, E_Entry, E_Entry_Family)
11960 or else Is_Subprogram_Or_Generic_Subprogram (Id)
11962 Set_Has_Out_Or_In_Out_Parameter (Id, True);
11965 if Ekind_In (Id, E_Function, E_Generic_Function) then
11967 -- [IN] OUT parameters allowed for functions in Ada 2012
11969 if Ada_Version >= Ada_2012 then
11971 -- Even in Ada 2012 operators can only have IN parameters
11973 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11974 Error_Msg_N ("operators can only have IN parameters", Spec);
11977 if In_Present (Spec) then
11978 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11980 Set_Ekind (Formal_Id, E_Out_Parameter);
11983 -- But not in earlier versions of Ada
11986 Error_Msg_N ("functions can only have IN parameters", Spec);
11987 Set_Ekind (Formal_Id, E_In_Parameter);
11990 elsif In_Present (Spec) then
11991 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11994 Set_Ekind (Formal_Id, E_Out_Parameter);
11995 Set_Never_Set_In_Source (Formal_Id, True);
11996 Set_Is_True_Constant (Formal_Id, False);
11997 Set_Current_Value (Formal_Id, Empty);
12001 Set_Ekind (Formal_Id, E_In_Parameter);
12004 -- Set Is_Known_Non_Null for access parameters since the language
12005 -- guarantees that access parameters are always non-null. We also set
12006 -- Can_Never_Be_Null, since there is no way to change the value.
12008 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
12010 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
12011 -- null; In Ada 2005, only if then null_exclusion is explicit.
12013 if Ada_Version < Ada_2005
12014 or else Can_Never_Be_Null (Etype (Formal_Id))
12016 Set_Is_Known_Non_Null (Formal_Id);
12017 Set_Can_Never_Be_Null (Formal_Id);
12020 -- Ada 2005 (AI-231): Null-exclusion access subtype
12022 elsif Is_Access_Type (Etype (Formal_Id))
12023 and then Can_Never_Be_Null (Etype (Formal_Id))
12025 Set_Is_Known_Non_Null (Formal_Id);
12027 -- We can also set Can_Never_Be_Null (thus preventing some junk
12028 -- access checks) for the case of an IN parameter, which cannot
12029 -- be changed, or for an IN OUT parameter, which can be changed but
12030 -- not to a null value. But for an OUT parameter, the initial value
12031 -- passed in can be null, so we can't set this flag in that case.
12033 if Ekind (Formal_Id) /= E_Out_Parameter then
12034 Set_Can_Never_Be_Null (Formal_Id);
12038 Set_Mechanism (Formal_Id, Default_Mechanism);
12039 Set_Formal_Validity (Formal_Id);
12040 end Set_Formal_Mode;
12042 -------------------------
12043 -- Set_Formal_Validity --
12044 -------------------------
12046 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
12048 -- If no validity checking, then we cannot assume anything about the
12049 -- validity of parameters, since we do not know there is any checking
12050 -- of the validity on the call side.
12052 if not Validity_Checks_On then
12055 -- If validity checking for parameters is enabled, this means we are
12056 -- not supposed to make any assumptions about argument values.
12058 elsif Validity_Check_Parameters then
12061 -- If we are checking in parameters, we will assume that the caller is
12062 -- also checking parameters, so we can assume the parameter is valid.
12064 elsif Ekind (Formal_Id) = E_In_Parameter
12065 and then Validity_Check_In_Params
12067 Set_Is_Known_Valid (Formal_Id, True);
12069 -- Similar treatment for IN OUT parameters
12071 elsif Ekind (Formal_Id) = E_In_Out_Parameter
12072 and then Validity_Check_In_Out_Params
12074 Set_Is_Known_Valid (Formal_Id, True);
12076 end Set_Formal_Validity;
12078 ------------------------
12079 -- Subtype_Conformant --
12080 ------------------------
12082 function Subtype_Conformant
12083 (New_Id : Entity_Id;
12084 Old_Id : Entity_Id;
12085 Skip_Controlling_Formals : Boolean := False) return Boolean
12089 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
12090 Skip_Controlling_Formals => Skip_Controlling_Formals);
12092 end Subtype_Conformant;
12094 ---------------------
12095 -- Type_Conformant --
12096 ---------------------
12098 function Type_Conformant
12099 (New_Id : Entity_Id;
12100 Old_Id : Entity_Id;
12101 Skip_Controlling_Formals : Boolean := False) return Boolean
12105 May_Hide_Profile := False;
12107 (New_Id, Old_Id, Type_Conformant, False, Result,
12108 Skip_Controlling_Formals => Skip_Controlling_Formals);
12110 end Type_Conformant;
12112 -------------------------------
12113 -- Valid_Operator_Definition --
12114 -------------------------------
12116 procedure Valid_Operator_Definition (Designator : Entity_Id) is
12119 Id : constant Name_Id := Chars (Designator);
12123 F := First_Formal (Designator);
12124 while Present (F) loop
12127 if Present (Default_Value (F)) then
12129 ("default values not allowed for operator parameters",
12132 -- For function instantiations that are operators, we must check
12133 -- separately that the corresponding generic only has in-parameters.
12134 -- For subprogram declarations this is done in Set_Formal_Mode. Such
12135 -- an error could not arise in earlier versions of the language.
12137 elsif Ekind (F) /= E_In_Parameter then
12138 Error_Msg_N ("operators can only have IN parameters", F);
12144 -- Verify that user-defined operators have proper number of arguments
12145 -- First case of operators which can only be unary
12147 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
12150 -- Case of operators which can be unary or binary
12152 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
12153 N_OK := (N in 1 .. 2);
12155 -- All other operators can only be binary
12163 ("incorrect number of arguments for operator", Designator);
12167 and then Base_Type (Etype (Designator)) = Standard_Boolean
12168 and then not Is_Intrinsic_Subprogram (Designator)
12171 ("explicit definition of inequality not allowed", Designator);
12173 end Valid_Operator_Definition;