1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2013, 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 Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Errout; use Errout;
33 with Expander; use Expander;
34 with Exp_Ch6; use Exp_Ch6;
35 with Exp_Ch7; use Exp_Ch7;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Dbug; use Exp_Dbug;
38 with Exp_Disp; use Exp_Disp;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Fname; use Fname;
42 with Freeze; use Freeze;
43 with Itypes; use Itypes;
44 with Lib.Xref; use Lib.Xref;
45 with Layout; use Layout;
46 with Namet; use Namet;
48 with Nlists; use Nlists;
49 with Nmake; use Nmake;
51 with Output; use Output;
52 with Restrict; use Restrict;
53 with Rident; use Rident;
54 with Rtsfind; use Rtsfind;
56 with Sem_Aux; use Sem_Aux;
57 with Sem_Cat; use Sem_Cat;
58 with Sem_Ch3; use Sem_Ch3;
59 with Sem_Ch4; use Sem_Ch4;
60 with Sem_Ch5; use Sem_Ch5;
61 with Sem_Ch8; use Sem_Ch8;
62 with Sem_Ch10; use Sem_Ch10;
63 with Sem_Ch12; use Sem_Ch12;
64 with Sem_Ch13; use Sem_Ch13;
65 with Sem_Dim; use Sem_Dim;
66 with Sem_Disp; use Sem_Disp;
67 with Sem_Dist; use Sem_Dist;
68 with Sem_Elim; use Sem_Elim;
69 with Sem_Eval; use Sem_Eval;
70 with Sem_Mech; use Sem_Mech;
71 with Sem_Prag; use Sem_Prag;
72 with Sem_Res; use Sem_Res;
73 with Sem_Util; use Sem_Util;
74 with Sem_Type; use Sem_Type;
75 with Sem_Warn; use Sem_Warn;
76 with Sinput; use Sinput;
77 with Stand; use Stand;
78 with Sinfo; use Sinfo;
79 with Sinfo.CN; use Sinfo.CN;
80 with Snames; use Snames;
81 with Stringt; use Stringt;
83 with Stylesw; use Stylesw;
84 with Targparm; use Targparm;
85 with Tbuild; use Tbuild;
86 with Uintp; use Uintp;
87 with Urealp; use Urealp;
88 with Validsw; use Validsw;
90 package body Sem_Ch6 is
92 May_Hide_Profile : Boolean := False;
93 -- This flag is used to indicate that two formals in two subprograms being
94 -- checked for conformance differ only in that one is an access parameter
95 -- while the other is of a general access type with the same designated
96 -- type. In this case, if the rest of the signatures match, a call to
97 -- either subprogram may be ambiguous, which is worth a warning. The flag
98 -- is set in Compatible_Types, and the warning emitted in
99 -- New_Overloaded_Entity.
101 -----------------------
102 -- Local Subprograms --
103 -----------------------
105 procedure Analyze_Null_Procedure
107 Is_Completion : out Boolean);
108 -- A null procedure can be a declaration or (Ada 2012) a completion.
110 procedure Analyze_Return_Statement (N : Node_Id);
111 -- Common processing for simple and extended return statements
113 procedure Analyze_Function_Return (N : Node_Id);
114 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
115 -- applies to a [generic] function.
117 procedure Analyze_Return_Type (N : Node_Id);
118 -- Subsidiary to Process_Formals: analyze subtype mark in function
119 -- specification in a context where the formals are visible and hide
122 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
123 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
124 -- that we can use RETURN but not skip the debug output at the end.
126 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
127 -- Analyze a generic subprogram body. N is the body to be analyzed, and
128 -- Gen_Id is the defining entity Id for the corresponding spec.
130 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
131 -- If a subprogram has pragma Inline and inlining is active, use generic
132 -- machinery to build an unexpanded body for the subprogram. This body is
133 -- subsequently used for inline expansions at call sites. If subprogram can
134 -- be inlined (depending on size and nature of local declarations) this
135 -- function returns true. Otherwise subprogram body is treated normally.
136 -- If proper warnings are enabled and the subprogram contains a construct
137 -- that cannot be inlined, the offending construct is flagged accordingly.
139 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
140 -- Returns true if Subp can override a predefined operator.
142 procedure Check_And_Build_Body_To_Inline
145 Body_Id : Entity_Id);
146 -- Spec_Id and Body_Id are the entities of the specification and body of
147 -- the subprogram body N. If N can be inlined by the frontend (supported
148 -- cases documented in Check_Body_To_Inline) then build the body-to-inline
149 -- associated with N and attach it to the declaration node of Spec_Id.
151 procedure Check_Conformance
154 Ctype : Conformance_Type;
156 Conforms : out Boolean;
157 Err_Loc : Node_Id := Empty;
158 Get_Inst : Boolean := False;
159 Skip_Controlling_Formals : Boolean := False);
160 -- Given two entities, this procedure checks that the profiles associated
161 -- with these entities meet the conformance criterion given by the third
162 -- parameter. If they conform, Conforms is set True and control returns
163 -- to the caller. If they do not conform, Conforms is set to False, and
164 -- in addition, if Errmsg is True on the call, proper messages are output
165 -- to complain about the conformance failure. If Err_Loc is non_Empty
166 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
167 -- error messages are placed on the appropriate part of the construct
168 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
169 -- against a formal access-to-subprogram type so Get_Instance_Of must
172 procedure Check_Subprogram_Order (N : Node_Id);
173 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
174 -- the alpha ordering rule for N if this ordering requirement applicable.
176 procedure Check_Returns
180 Proc : Entity_Id := Empty);
181 -- Called to check for missing return statements in a function body, or for
182 -- returns present in a procedure body which has No_Return set. HSS is the
183 -- handled statement sequence for the subprogram body. This procedure
184 -- checks all flow paths to make sure they either have return (Mode = 'F',
185 -- used for functions) or do not have a return (Mode = 'P', used for
186 -- No_Return procedures). The flag Err is set if there are any control
187 -- paths not explicitly terminated by a return in the function case, and is
188 -- True otherwise. Proc is the entity for the procedure case and is used
189 -- in posting the warning message.
191 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
192 -- In Ada 2012, a primitive equality operator on an untagged record type
193 -- must appear before the type is frozen, and have the same visibility as
194 -- that of the type. This procedure checks that this rule is met, and
195 -- otherwise emits an error on the subprogram declaration and a warning
196 -- on the earlier freeze point if it is easy to locate.
198 procedure Enter_Overloaded_Entity (S : Entity_Id);
199 -- This procedure makes S, a new overloaded entity, into the first visible
200 -- entity with that name.
202 function Is_Non_Overriding_Operation
204 New_E : Entity_Id) return Boolean;
205 -- Enforce the rule given in 12.3(18): a private operation in an instance
206 -- overrides an inherited operation only if the corresponding operation
207 -- was overriding in the generic. This needs to be checked for primitive
208 -- operations of types derived (in the generic unit) from formal private
209 -- or formal derived types.
211 procedure Make_Inequality_Operator (S : Entity_Id);
212 -- Create the declaration for an inequality operator that is implicitly
213 -- created by a user-defined equality operator that yields a boolean.
215 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
216 -- Formal_Id is an formal parameter entity. This procedure deals with
217 -- setting the proper validity status for this entity, which depends on
218 -- the kind of parameter and the validity checking mode.
220 ---------------------------------------------
221 -- Analyze_Abstract_Subprogram_Declaration --
222 ---------------------------------------------
224 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
225 Designator : constant Entity_Id :=
226 Analyze_Subprogram_Specification (Specification (N));
227 Scop : constant Entity_Id := Current_Scope;
230 Check_SPARK_Restriction ("abstract subprogram is not allowed", N);
232 Generate_Definition (Designator);
233 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
234 Set_Is_Abstract_Subprogram (Designator);
235 New_Overloaded_Entity (Designator);
236 Check_Delayed_Subprogram (Designator);
238 Set_Categorization_From_Scope (Designator, Scop);
240 if Ekind (Scope (Designator)) = E_Protected_Type then
242 ("abstract subprogram not allowed in protected type", N);
244 -- Issue a warning if the abstract subprogram is neither a dispatching
245 -- operation nor an operation that overrides an inherited subprogram or
246 -- predefined operator, since this most likely indicates a mistake.
248 elsif Warn_On_Redundant_Constructs
249 and then not Is_Dispatching_Operation (Designator)
250 and then not Present (Overridden_Operation (Designator))
251 and then (not Is_Operator_Symbol_Name (Chars (Designator))
252 or else Scop /= Scope (Etype (First_Formal (Designator))))
255 ("abstract subprogram is not dispatching or overriding?r?", N);
258 Generate_Reference_To_Formals (Designator);
259 Check_Eliminated (Designator);
261 if Has_Aspects (N) then
262 Analyze_Aspect_Specifications (N, Designator);
264 end Analyze_Abstract_Subprogram_Declaration;
266 ---------------------------------
267 -- Analyze_Expression_Function --
268 ---------------------------------
270 procedure Analyze_Expression_Function (N : Node_Id) is
271 Loc : constant Source_Ptr := Sloc (N);
272 LocX : constant Source_Ptr := Sloc (Expression (N));
273 Expr : constant Node_Id := Expression (N);
274 Spec : constant Node_Id := Specification (N);
279 -- If the expression is a completion, Prev is the entity whose
280 -- declaration is completed. Def_Id is needed to analyze the spec.
288 -- This is one of the occasions on which we transform the tree during
289 -- semantic analysis. If this is a completion, transform the expression
290 -- function into an equivalent subprogram body, and analyze it.
292 -- Expression functions are inlined unconditionally. The back-end will
293 -- determine whether this is possible.
295 Inline_Processing_Required := True;
297 -- Create a specification for the generated body. Types and defauts in
298 -- the profile are copies of the spec, but new entities must be created
299 -- for the unit name and the formals.
301 New_Spec := New_Copy_Tree (Spec);
302 Set_Defining_Unit_Name (New_Spec,
303 Make_Defining_Identifier (Sloc (Defining_Unit_Name (Spec)),
304 Chars (Defining_Unit_Name (Spec))));
306 if Present (Parameter_Specifications (New_Spec)) then
308 Formal_Spec : Node_Id;
310 Formal_Spec := First (Parameter_Specifications (New_Spec));
311 while Present (Formal_Spec) loop
312 Set_Defining_Identifier
314 Make_Defining_Identifier (Sloc (Formal_Spec),
315 Chars => Chars (Defining_Identifier (Formal_Spec))));
321 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
323 -- If there are previous overloadable entities with the same name,
324 -- check whether any of them is completed by the expression function.
326 if Present (Prev) and then Is_Overloadable (Prev) then
327 Def_Id := Analyze_Subprogram_Specification (Spec);
328 Prev := Find_Corresponding_Spec (N);
331 Ret := Make_Simple_Return_Statement (LocX, Expression (N));
334 Make_Subprogram_Body (Loc,
335 Specification => New_Spec,
336 Declarations => Empty_List,
337 Handled_Statement_Sequence =>
338 Make_Handled_Sequence_Of_Statements (LocX,
339 Statements => New_List (Ret)));
341 -- If the expression completes a generic subprogram, we must create a
342 -- separate node for the body, because at instantiation the original
343 -- node of the generic copy must be a generic subprogram body, and
344 -- cannot be a expression function. Otherwise we just rewrite the
345 -- expression with the non-generic body.
347 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
348 Insert_After (N, New_Body);
350 -- Propagate any aspects or pragmas that apply to the expression
351 -- function to the proper body when the expression function acts
354 if Has_Aspects (N) then
355 Move_Aspects (N, To => New_Body);
358 Relocate_Pragmas_To_Body (New_Body);
360 Rewrite (N, Make_Null_Statement (Loc));
361 Set_Has_Completion (Prev, False);
364 Set_Is_Inlined (Prev);
366 elsif Present (Prev) and then Comes_From_Source (Prev) then
367 Set_Has_Completion (Prev, False);
369 -- For navigation purposes, indicate that the function is a body
371 Generate_Reference (Prev, Defining_Entity (N), 'b', Force => True);
372 Rewrite (N, New_Body);
374 -- Propagate any pragmas that apply to the expression function to the
375 -- proper body when the expression function acts as a completion.
376 -- Aspects are automatically transfered because of node rewriting.
378 Relocate_Pragmas_To_Body (N);
381 -- Prev is the previous entity with the same name, but it is can
382 -- be an unrelated spec that is not completed by the expression
383 -- function. In that case the relevant entity is the one in the body.
384 -- Not clear that the backend can inline it in this case ???
386 if Has_Completion (Prev) then
387 Set_Is_Inlined (Prev);
389 -- The formals of the expression function are body formals,
390 -- and do not appear in the ali file, which will only contain
391 -- references to the formals of the original subprogram spec.
398 F1 := First_Formal (Def_Id);
399 F2 := First_Formal (Prev);
401 while Present (F1) loop
402 Set_Spec_Entity (F1, F2);
409 Set_Is_Inlined (Defining_Entity (New_Body));
412 -- If this is not a completion, create both a declaration and a body, so
413 -- that the expression can be inlined whenever possible.
416 -- An expression function that is not a completion is not a
417 -- subprogram declaration, and thus cannot appear in a protected
420 if Nkind (Parent (N)) = N_Protected_Definition then
422 ("an expression function is not a legal protected operation", N);
426 Make_Subprogram_Declaration (Loc, Specification => Spec);
428 Rewrite (N, New_Decl);
430 Set_Is_Inlined (Defining_Entity (New_Decl));
432 -- To prevent premature freeze action, insert the new body at the end
433 -- of the current declarations, or at the end of the package spec.
434 -- However, resolve usage names now, to prevent spurious visibility
435 -- on later entities.
438 Decls : List_Id := List_Containing (N);
439 Par : constant Node_Id := Parent (Decls);
440 Id : constant Entity_Id := Defining_Entity (New_Decl);
443 if Nkind (Par) = N_Package_Specification
444 and then Decls = Visible_Declarations (Par)
445 and then Present (Private_Declarations (Par))
446 and then not Is_Empty_List (Private_Declarations (Par))
448 Decls := Private_Declarations (Par);
451 Insert_After (Last (Decls), New_Body);
453 Install_Formals (Id);
455 -- Do a preanalysis of the expression on a separate copy, to
456 -- prevent visibility issues later with operators in instances.
457 -- Attach copy to tree so that parent links are available.
460 Expr : constant Node_Id := New_Copy_Tree (Expression (Ret));
462 Set_Parent (Expr, Ret);
463 Preanalyze_Spec_Expression (Expr, Etype (Id));
470 -- If the return expression is a static constant, we suppress warning
471 -- messages on unused formals, which in most cases will be noise.
473 Set_Is_Trivial_Subprogram (Defining_Entity (New_Body),
474 Is_OK_Static_Expression (Expr));
475 end Analyze_Expression_Function;
477 ----------------------------------------
478 -- Analyze_Extended_Return_Statement --
479 ----------------------------------------
481 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
483 Analyze_Return_Statement (N);
484 end Analyze_Extended_Return_Statement;
486 ----------------------------
487 -- Analyze_Function_Call --
488 ----------------------------
490 procedure Analyze_Function_Call (N : Node_Id) is
491 Actuals : constant List_Id := Parameter_Associations (N);
492 Func_Nam : constant Node_Id := Name (N);
498 -- A call of the form A.B (X) may be an Ada 2005 call, which is
499 -- rewritten as B (A, X). If the rewriting is successful, the call
500 -- has been analyzed and we just return.
502 if Nkind (Func_Nam) = N_Selected_Component
503 and then Name (N) /= Func_Nam
504 and then Is_Rewrite_Substitution (N)
505 and then Present (Etype (N))
510 -- If error analyzing name, then set Any_Type as result type and return
512 if Etype (Func_Nam) = Any_Type then
513 Set_Etype (N, Any_Type);
517 -- Otherwise analyze the parameters
519 if Present (Actuals) then
520 Actual := First (Actuals);
521 while Present (Actual) loop
523 Check_Parameterless_Call (Actual);
529 end Analyze_Function_Call;
531 -----------------------------
532 -- Analyze_Function_Return --
533 -----------------------------
535 procedure Analyze_Function_Return (N : Node_Id) is
536 Loc : constant Source_Ptr := Sloc (N);
537 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
538 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
540 R_Type : constant Entity_Id := Etype (Scope_Id);
541 -- Function result subtype
543 procedure Check_Limited_Return (Expr : Node_Id);
544 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
545 -- limited types. Used only for simple return statements.
546 -- Expr is the expression returned.
548 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
549 -- Check that the return_subtype_indication properly matches the result
550 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
552 --------------------------
553 -- Check_Limited_Return --
554 --------------------------
556 procedure Check_Limited_Return (Expr : Node_Id) is
558 -- Ada 2005 (AI-318-02): Return-by-reference types have been
559 -- removed and replaced by anonymous access results. This is an
560 -- incompatibility with Ada 95. Not clear whether this should be
561 -- enforced yet or perhaps controllable with special switch. ???
563 -- A limited interface that is not immutably limited is OK.
565 if Is_Limited_Interface (R_Type)
567 not (Is_Task_Interface (R_Type)
568 or else Is_Protected_Interface (R_Type)
569 or else Is_Synchronized_Interface (R_Type))
573 elsif Is_Limited_Type (R_Type)
574 and then not Is_Interface (R_Type)
575 and then Comes_From_Source (N)
576 and then not In_Instance_Body
577 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
581 if Ada_Version >= Ada_2005
582 and then not Debug_Flag_Dot_L
583 and then not GNAT_Mode
586 ("(Ada 2005) cannot copy object of a limited type " &
587 "(RM-2005 6.5(5.5/2))", Expr);
589 if Is_Immutably_Limited_Type (R_Type) then
591 ("\return by reference not permitted in Ada 2005", Expr);
594 -- Warn in Ada 95 mode, to give folks a heads up about this
597 -- In GNAT mode, this is just a warning, to allow it to be
598 -- evilly turned off. Otherwise it is a real error.
600 -- In a generic context, simplify the warning because it makes
601 -- no sense to discuss pass-by-reference or copy.
603 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
604 if Inside_A_Generic then
606 ("return of limited object not permitted in Ada 2005 "
607 & "(RM-2005 6.5(5.5/2))?y?", Expr);
609 elsif Is_Immutably_Limited_Type (R_Type) then
611 ("return by reference not permitted in Ada 2005 "
612 & "(RM-2005 6.5(5.5/2))?y?", Expr);
615 ("cannot copy object of a limited type in Ada 2005 "
616 & "(RM-2005 6.5(5.5/2))?y?", Expr);
619 -- Ada 95 mode, compatibility warnings disabled
622 return; -- skip continuation messages below
625 if not Inside_A_Generic then
627 ("\consider switching to return of access type", Expr);
628 Explain_Limited_Type (R_Type, Expr);
631 end Check_Limited_Return;
633 -------------------------------------
634 -- Check_Return_Subtype_Indication --
635 -------------------------------------
637 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
638 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
640 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
641 -- Subtype given in the extended return statement (must match R_Type)
643 Subtype_Ind : constant Node_Id :=
644 Object_Definition (Original_Node (Obj_Decl));
646 R_Type_Is_Anon_Access :
648 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
650 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
652 Ekind (R_Type) = E_Anonymous_Access_Type;
653 -- True if return type of the function is an anonymous access type
654 -- Can't we make Is_Anonymous_Access_Type in einfo ???
656 R_Stm_Type_Is_Anon_Access :
658 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
660 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
662 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
663 -- True if type of the return object is an anonymous access type
666 -- First, avoid cascaded errors
668 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
672 -- "return access T" case; check that the return statement also has
673 -- "access T", and that the subtypes statically match:
674 -- if this is an access to subprogram the signatures must match.
676 if R_Type_Is_Anon_Access then
677 if R_Stm_Type_Is_Anon_Access then
679 Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
681 if Base_Type (Designated_Type (R_Stm_Type)) /=
682 Base_Type (Designated_Type (R_Type))
683 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
686 ("subtype must statically match function result subtype",
687 Subtype_Mark (Subtype_Ind));
691 -- For two anonymous access to subprogram types, the
692 -- types themselves must be type conformant.
694 if not Conforming_Types
695 (R_Stm_Type, R_Type, Fully_Conformant)
698 ("subtype must statically match function result subtype",
704 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
707 -- If the return object is of an anonymous access type, then report
708 -- an error if the function's result type is not also anonymous.
710 elsif R_Stm_Type_Is_Anon_Access
711 and then not R_Type_Is_Anon_Access
713 Error_Msg_N ("anonymous access not allowed for function with " &
714 "named access result", Subtype_Ind);
716 -- Subtype indication case: check that the return object's type is
717 -- covered by the result type, and that the subtypes statically match
718 -- when the result subtype is constrained. Also handle record types
719 -- with unknown discriminants for which we have built the underlying
720 -- record view. Coverage is needed to allow specific-type return
721 -- objects when the result type is class-wide (see AI05-32).
723 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
724 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
728 Underlying_Record_View (Base_Type (R_Stm_Type))))
730 -- A null exclusion may be present on the return type, on the
731 -- function specification, on the object declaration or on the
734 if Is_Access_Type (R_Type)
736 (Can_Never_Be_Null (R_Type)
737 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
738 Can_Never_Be_Null (R_Stm_Type)
741 ("subtype must statically match function result subtype",
745 -- AI05-103: for elementary types, subtypes must statically match
747 if Is_Constrained (R_Type)
748 or else Is_Access_Type (R_Type)
750 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
752 ("subtype must statically match function result subtype",
757 elsif Etype (Base_Type (R_Type)) = R_Stm_Type
758 and then Is_Null_Extension (Base_Type (R_Type))
764 ("wrong type for return_subtype_indication", Subtype_Ind);
766 end Check_Return_Subtype_Indication;
768 ---------------------
769 -- Local Variables --
770 ---------------------
774 -- Start of processing for Analyze_Function_Return
777 Set_Return_Present (Scope_Id);
779 if Nkind (N) = N_Simple_Return_Statement then
780 Expr := Expression (N);
782 -- Guard against a malformed expression. The parser may have tried to
783 -- recover but the node is not analyzable.
785 if Nkind (Expr) = N_Error then
786 Set_Etype (Expr, Any_Type);
787 Expander_Mode_Save_And_Set (False);
791 -- The resolution of a controlled [extension] aggregate associated
792 -- with a return statement creates a temporary which needs to be
793 -- finalized on function exit. Wrap the return statement inside a
794 -- block so that the finalization machinery can detect this case.
795 -- This early expansion is done only when the return statement is
796 -- not part of a handled sequence of statements.
798 if Nkind_In (Expr, N_Aggregate,
799 N_Extension_Aggregate)
800 and then Needs_Finalization (R_Type)
801 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
804 Make_Block_Statement (Loc,
805 Handled_Statement_Sequence =>
806 Make_Handled_Sequence_Of_Statements (Loc,
807 Statements => New_List (Relocate_Node (N)))));
813 Analyze_And_Resolve (Expr, R_Type);
814 Check_Limited_Return (Expr);
817 -- RETURN only allowed in SPARK as the last statement in function
819 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
821 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
822 or else Present (Next (N)))
824 Check_SPARK_Restriction
825 ("RETURN should be the last statement in function", N);
829 Check_SPARK_Restriction ("extended RETURN is not allowed", N);
831 -- Analyze parts specific to extended_return_statement:
834 Obj_Decl : constant Node_Id :=
835 Last (Return_Object_Declarations (N));
836 Has_Aliased : constant Boolean := Aliased_Present (Obj_Decl);
837 HSS : constant Node_Id := Handled_Statement_Sequence (N);
840 Expr := Expression (Obj_Decl);
842 -- Note: The check for OK_For_Limited_Init will happen in
843 -- Analyze_Object_Declaration; we treat it as a normal
844 -- object declaration.
846 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
849 Check_Return_Subtype_Indication (Obj_Decl);
851 if Present (HSS) then
854 if Present (Exception_Handlers (HSS)) then
856 -- ???Has_Nested_Block_With_Handler needs to be set.
857 -- Probably by creating an actual N_Block_Statement.
858 -- Probably in Expand.
864 -- Mark the return object as referenced, since the return is an
865 -- implicit reference of the object.
867 Set_Referenced (Defining_Identifier (Obj_Decl));
869 Check_References (Stm_Entity);
871 -- Check RM 6.5 (5.9/3)
874 if Ada_Version < Ada_2012 then
876 -- Shouldn't this test Warn_On_Ada_2012_Compatibility ???
877 -- Can it really happen (extended return???)
880 ("aliased only allowed for limited"
881 & " return objects in Ada 2012?", N);
883 elsif not Is_Immutably_Limited_Type (R_Type) then
884 Error_Msg_N ("aliased only allowed for limited"
885 & " return objects", N);
891 -- Case of Expr present
895 -- Defend against previous errors
897 and then Nkind (Expr) /= N_Empty
898 and then Present (Etype (Expr))
900 -- Apply constraint check. Note that this is done before the implicit
901 -- conversion of the expression done for anonymous access types to
902 -- ensure correct generation of the null-excluding check associated
903 -- with null-excluding expressions found in return statements.
905 Apply_Constraint_Check (Expr, R_Type);
907 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
908 -- type, apply an implicit conversion of the expression to that type
909 -- to force appropriate static and run-time accessibility checks.
911 if Ada_Version >= Ada_2005
912 and then Ekind (R_Type) = E_Anonymous_Access_Type
914 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
915 Analyze_And_Resolve (Expr, R_Type);
917 -- If this is a local anonymous access to subprogram, the
918 -- accessibility check can be applied statically. The return is
919 -- illegal if the access type of the return expression is declared
920 -- inside of the subprogram (except if it is the subtype indication
921 -- of an extended return statement).
923 elsif Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type then
924 if not Comes_From_Source (Current_Scope)
925 or else Ekind (Current_Scope) = E_Return_Statement
930 Scope_Depth (Scope (Etype (Expr))) >= Scope_Depth (Scope_Id)
932 Error_Msg_N ("cannot return local access to subprogram", N);
936 -- If the result type is class-wide, then check that the return
937 -- expression's type is not declared at a deeper level than the
938 -- function (RM05-6.5(5.6/2)).
940 if Ada_Version >= Ada_2005
941 and then Is_Class_Wide_Type (R_Type)
943 if Type_Access_Level (Etype (Expr)) >
944 Subprogram_Access_Level (Scope_Id)
947 ("level of return expression type is deeper than " &
948 "class-wide function!", Expr);
952 -- Check incorrect use of dynamically tagged expression
954 if Is_Tagged_Type (R_Type) then
955 Check_Dynamically_Tagged_Expression
961 -- ??? A real run-time accessibility check is needed in cases
962 -- involving dereferences of access parameters. For now we just
963 -- check the static cases.
965 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
966 and then Is_Immutably_Limited_Type (Etype (Scope_Id))
967 and then Object_Access_Level (Expr) >
968 Subprogram_Access_Level (Scope_Id)
970 -- Suppress the message in a generic, where the rewriting
973 if Inside_A_Generic then
978 Make_Raise_Program_Error (Loc,
979 Reason => PE_Accessibility_Check_Failed));
983 ("cannot return a local value by reference??", N);
985 ("\& will be raised at run time??",
986 N, Standard_Program_Error);
991 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
992 and then Null_Exclusion_Present (Parent (Scope_Id))
994 Apply_Compile_Time_Constraint_Error
996 Msg => "(Ada 2005) null not allowed for "
997 & "null-excluding return??",
998 Reason => CE_Null_Not_Allowed);
1001 end Analyze_Function_Return;
1003 -------------------------------------
1004 -- Analyze_Generic_Subprogram_Body --
1005 -------------------------------------
1007 procedure Analyze_Generic_Subprogram_Body
1011 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
1012 Kind : constant Entity_Kind := Ekind (Gen_Id);
1013 Body_Id : Entity_Id;
1018 -- Copy body and disable expansion while analyzing the generic For a
1019 -- stub, do not copy the stub (which would load the proper body), this
1020 -- will be done when the proper body is analyzed.
1022 if Nkind (N) /= N_Subprogram_Body_Stub then
1023 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
1028 Spec := Specification (N);
1030 -- Within the body of the generic, the subprogram is callable, and
1031 -- behaves like the corresponding non-generic unit.
1033 Body_Id := Defining_Entity (Spec);
1035 if Kind = E_Generic_Procedure
1036 and then Nkind (Spec) /= N_Procedure_Specification
1038 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
1041 elsif Kind = E_Generic_Function
1042 and then Nkind (Spec) /= N_Function_Specification
1044 Error_Msg_N ("invalid body for generic function ", Body_Id);
1048 Set_Corresponding_Body (Gen_Decl, Body_Id);
1050 if Has_Completion (Gen_Id)
1051 and then Nkind (Parent (N)) /= N_Subunit
1053 Error_Msg_N ("duplicate generic body", N);
1056 Set_Has_Completion (Gen_Id);
1059 if Nkind (N) = N_Subprogram_Body_Stub then
1060 Set_Ekind (Defining_Entity (Specification (N)), Kind);
1062 Set_Corresponding_Spec (N, Gen_Id);
1065 if Nkind (Parent (N)) = N_Compilation_Unit then
1066 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
1069 -- Make generic parameters immediately visible in the body. They are
1070 -- needed to process the formals declarations. Then make the formals
1071 -- visible in a separate step.
1073 Push_Scope (Gen_Id);
1077 First_Ent : Entity_Id;
1080 First_Ent := First_Entity (Gen_Id);
1083 while Present (E) and then not Is_Formal (E) loop
1088 Set_Use (Generic_Formal_Declarations (Gen_Decl));
1090 -- Now generic formals are visible, and the specification can be
1091 -- analyzed, for subsequent conformance check.
1093 Body_Id := Analyze_Subprogram_Specification (Spec);
1095 -- Make formal parameters visible
1099 -- E is the first formal parameter, we loop through the formals
1100 -- installing them so that they will be visible.
1102 Set_First_Entity (Gen_Id, E);
1103 while Present (E) loop
1109 -- Visible generic entity is callable within its own body
1111 Set_Ekind (Gen_Id, Ekind (Body_Id));
1112 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
1113 Set_Ekind (Body_Id, E_Subprogram_Body);
1114 Set_Convention (Body_Id, Convention (Gen_Id));
1115 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
1116 Set_Scope (Body_Id, Scope (Gen_Id));
1117 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
1119 if Nkind (N) = N_Subprogram_Body_Stub then
1121 -- No body to analyze, so restore state of generic unit
1123 Set_Ekind (Gen_Id, Kind);
1124 Set_Ekind (Body_Id, Kind);
1126 if Present (First_Ent) then
1127 Set_First_Entity (Gen_Id, First_Ent);
1134 -- If this is a compilation unit, it must be made visible explicitly,
1135 -- because the compilation of the declaration, unlike other library
1136 -- unit declarations, does not. If it is not a unit, the following
1137 -- is redundant but harmless.
1139 Set_Is_Immediately_Visible (Gen_Id);
1140 Reference_Body_Formals (Gen_Id, Body_Id);
1142 if Is_Child_Unit (Gen_Id) then
1143 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1146 Set_Actual_Subtypes (N, Current_Scope);
1148 -- Deal with [refined] preconditions, postconditions, Contract_Cases,
1149 -- invariants and predicates associated with the body and its spec.
1150 -- Note that this is not pure expansion as Expand_Subprogram_Contract
1151 -- prepares the contract assertions for generic subprograms or for
1152 -- ASIS. Do not generate contract checks in SPARK mode.
1154 if not SPARK_Mode then
1155 Expand_Subprogram_Contract (N, Gen_Id, Body_Id);
1158 -- If the generic unit carries pre- or post-conditions, copy them
1159 -- to the original generic tree, so that they are properly added
1160 -- to any instantiation.
1163 Orig : constant Node_Id := Original_Node (N);
1167 Cond := First (Declarations (N));
1168 while Present (Cond) loop
1169 if Nkind (Cond) = N_Pragma
1170 and then Pragma_Name (Cond) = Name_Check
1172 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1174 elsif Nkind (Cond) = N_Pragma
1175 and then Pragma_Name (Cond) = Name_Postcondition
1177 Set_Ekind (Defining_Entity (Orig), Ekind (Gen_Id));
1178 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1187 Analyze_Declarations (Declarations (N));
1189 Analyze (Handled_Statement_Sequence (N));
1191 Save_Global_References (Original_Node (N));
1193 -- Prior to exiting the scope, include generic formals again (if any
1194 -- are present) in the set of local entities.
1196 if Present (First_Ent) then
1197 Set_First_Entity (Gen_Id, First_Ent);
1200 Check_References (Gen_Id);
1203 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1205 Check_Subprogram_Order (N);
1207 -- Outside of its body, unit is generic again
1209 Set_Ekind (Gen_Id, Kind);
1210 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1213 Style.Check_Identifier (Body_Id, Gen_Id);
1217 end Analyze_Generic_Subprogram_Body;
1219 ----------------------------
1220 -- Analyze_Null_Procedure --
1221 ----------------------------
1223 procedure Analyze_Null_Procedure
1225 Is_Completion : out Boolean)
1227 Loc : constant Source_Ptr := Sloc (N);
1228 Spec : constant Node_Id := Specification (N);
1229 Designator : Entity_Id;
1231 Null_Body : Node_Id := Empty;
1235 -- Capture the profile of the null procedure before analysis, for
1236 -- expansion at the freeze point and at each point of call. The body is
1237 -- used if the procedure has preconditions, or if it is a completion. In
1238 -- the first case the body is analyzed at the freeze point, in the other
1239 -- it replaces the null procedure declaration.
1242 Make_Subprogram_Body (Loc,
1243 Specification => New_Copy_Tree (Spec),
1244 Declarations => New_List,
1245 Handled_Statement_Sequence =>
1246 Make_Handled_Sequence_Of_Statements (Loc,
1247 Statements => New_List (Make_Null_Statement (Loc))));
1249 -- Create new entities for body and formals
1251 Set_Defining_Unit_Name (Specification (Null_Body),
1252 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))));
1254 Form := First (Parameter_Specifications (Specification (Null_Body)));
1255 while Present (Form) loop
1256 Set_Defining_Identifier (Form,
1257 Make_Defining_Identifier (Loc, Chars (Defining_Identifier (Form))));
1261 -- Determine whether the null procedure may be a completion of a generic
1262 -- suprogram, in which case we use the new null body as the completion
1263 -- and set minimal semantic information on the original declaration,
1264 -- which is rewritten as a null statement.
1266 Prev := Current_Entity_In_Scope (Defining_Entity (Spec));
1268 if Present (Prev) and then Is_Generic_Subprogram (Prev) then
1269 Insert_Before (N, Null_Body);
1270 Set_Ekind (Defining_Entity (N), Ekind (Prev));
1271 Set_Contract (Defining_Entity (N), Make_Contract (Loc));
1273 Rewrite (N, Make_Null_Statement (Loc));
1274 Analyze_Generic_Subprogram_Body (Null_Body, Prev);
1275 Is_Completion := True;
1280 -- Resolve the types of the formals now, because the freeze point
1281 -- may appear in a different context, e.g. an instantiation.
1283 Form := First (Parameter_Specifications (Specification (Null_Body)));
1284 while Present (Form) loop
1285 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
1286 Find_Type (Parameter_Type (Form));
1289 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
1291 Find_Type (Subtype_Mark (Parameter_Type (Form)));
1294 -- The case of a null procedure with a formal that is an
1295 -- access_to_subprogram type, and that is used as an actual
1296 -- in an instantiation is left to the enthusiastic reader.
1305 -- If there are previous overloadable entities with the same name,
1306 -- check whether any of them is completed by the null procedure.
1308 if Present (Prev) and then Is_Overloadable (Prev) then
1309 Designator := Analyze_Subprogram_Specification (Spec);
1310 Prev := Find_Corresponding_Spec (N);
1313 if No (Prev) or else not Comes_From_Source (Prev) then
1314 Designator := Analyze_Subprogram_Specification (Spec);
1315 Set_Has_Completion (Designator);
1317 -- Signal to caller that this is a procedure declaration
1319 Is_Completion := False;
1321 -- Null procedures are always inlined, but generic formal subprograms
1322 -- which appear as such in the internal instance of formal packages,
1323 -- need no completion and are not marked Inline.
1326 and then Nkind (N) /= N_Formal_Concrete_Subprogram_Declaration
1328 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
1329 Set_Body_To_Inline (N, Null_Body);
1330 Set_Is_Inlined (Designator);
1334 -- The null procedure is a completion
1336 Is_Completion := True;
1338 if Expander_Active then
1339 Rewrite (N, Null_Body);
1343 Designator := Analyze_Subprogram_Specification (Spec);
1344 Set_Has_Completion (Designator);
1345 Set_Has_Completion (Prev);
1348 end Analyze_Null_Procedure;
1350 -----------------------------
1351 -- Analyze_Operator_Symbol --
1352 -----------------------------
1354 -- An operator symbol such as "+" or "and" may appear in context where the
1355 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1356 -- is just a string, as in (conjunction = "or"). In these cases the parser
1357 -- generates this node, and the semantics does the disambiguation. Other
1358 -- such case are actuals in an instantiation, the generic unit in an
1359 -- instantiation, and pragma arguments.
1361 procedure Analyze_Operator_Symbol (N : Node_Id) is
1362 Par : constant Node_Id := Parent (N);
1365 if (Nkind (Par) = N_Function_Call
1366 and then N = Name (Par))
1367 or else Nkind (Par) = N_Function_Instantiation
1368 or else (Nkind (Par) = N_Indexed_Component
1369 and then N = Prefix (Par))
1370 or else (Nkind (Par) = N_Pragma_Argument_Association
1371 and then not Is_Pragma_String_Literal (Par))
1372 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1373 or else (Nkind (Par) = N_Attribute_Reference
1374 and then Attribute_Name (Par) /= Name_Value)
1376 Find_Direct_Name (N);
1379 Change_Operator_Symbol_To_String_Literal (N);
1382 end Analyze_Operator_Symbol;
1384 -----------------------------------
1385 -- Analyze_Parameter_Association --
1386 -----------------------------------
1388 procedure Analyze_Parameter_Association (N : Node_Id) is
1390 Analyze (Explicit_Actual_Parameter (N));
1391 end Analyze_Parameter_Association;
1393 ----------------------------
1394 -- Analyze_Procedure_Call --
1395 ----------------------------
1397 procedure Analyze_Procedure_Call (N : Node_Id) is
1398 Loc : constant Source_Ptr := Sloc (N);
1399 P : constant Node_Id := Name (N);
1400 Actuals : constant List_Id := Parameter_Associations (N);
1404 procedure Analyze_Call_And_Resolve;
1405 -- Do Analyze and Resolve calls for procedure call
1406 -- At end, check illegal order dependence.
1408 ------------------------------
1409 -- Analyze_Call_And_Resolve --
1410 ------------------------------
1412 procedure Analyze_Call_And_Resolve is
1414 if Nkind (N) = N_Procedure_Call_Statement then
1416 Resolve (N, Standard_Void_Type);
1420 end Analyze_Call_And_Resolve;
1422 -- Start of processing for Analyze_Procedure_Call
1425 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1426 -- a procedure call or an entry call. The prefix may denote an access
1427 -- to subprogram type, in which case an implicit dereference applies.
1428 -- If the prefix is an indexed component (without implicit dereference)
1429 -- then the construct denotes a call to a member of an entire family.
1430 -- If the prefix is a simple name, it may still denote a call to a
1431 -- parameterless member of an entry family. Resolution of these various
1432 -- interpretations is delicate.
1436 -- If this is a call of the form Obj.Op, the call may have been
1437 -- analyzed and possibly rewritten into a block, in which case
1440 if Analyzed (N) then
1444 -- If there is an error analyzing the name (which may have been
1445 -- rewritten if the original call was in prefix notation) then error
1446 -- has been emitted already, mark node and return.
1448 if Error_Posted (N) or else Etype (Name (N)) = Any_Type then
1449 Set_Etype (N, Any_Type);
1453 -- Otherwise analyze the parameters
1455 if Present (Actuals) then
1456 Actual := First (Actuals);
1458 while Present (Actual) loop
1460 Check_Parameterless_Call (Actual);
1465 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1467 if Nkind (P) = N_Attribute_Reference
1468 and then Nam_In (Attribute_Name (P), Name_Elab_Spec,
1470 Name_Elab_Subp_Body)
1472 if Present (Actuals) then
1474 ("no parameters allowed for this call", First (Actuals));
1478 Set_Etype (N, Standard_Void_Type);
1481 elsif Is_Entity_Name (P)
1482 and then Is_Record_Type (Etype (Entity (P)))
1483 and then Remote_AST_I_Dereference (P)
1487 elsif Is_Entity_Name (P)
1488 and then Ekind (Entity (P)) /= E_Entry_Family
1490 if Is_Access_Type (Etype (P))
1491 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1492 and then No (Actuals)
1493 and then Comes_From_Source (N)
1495 Error_Msg_N ("missing explicit dereference in call", N);
1498 Analyze_Call_And_Resolve;
1500 -- If the prefix is the simple name of an entry family, this is
1501 -- a parameterless call from within the task body itself.
1503 elsif Is_Entity_Name (P)
1504 and then Nkind (P) = N_Identifier
1505 and then Ekind (Entity (P)) = E_Entry_Family
1506 and then Present (Actuals)
1507 and then No (Next (First (Actuals)))
1509 -- Can be call to parameterless entry family. What appears to be the
1510 -- sole argument is in fact the entry index. Rewrite prefix of node
1511 -- accordingly. Source representation is unchanged by this
1515 Make_Indexed_Component (Loc,
1517 Make_Selected_Component (Loc,
1518 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1519 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1520 Expressions => Actuals);
1521 Set_Name (N, New_N);
1522 Set_Etype (New_N, Standard_Void_Type);
1523 Set_Parameter_Associations (N, No_List);
1524 Analyze_Call_And_Resolve;
1526 elsif Nkind (P) = N_Explicit_Dereference then
1527 if Ekind (Etype (P)) = E_Subprogram_Type then
1528 Analyze_Call_And_Resolve;
1530 Error_Msg_N ("expect access to procedure in call", P);
1533 -- The name can be a selected component or an indexed component that
1534 -- yields an access to subprogram. Such a prefix is legal if the call
1535 -- has parameter associations.
1537 elsif Is_Access_Type (Etype (P))
1538 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1540 if Present (Actuals) then
1541 Analyze_Call_And_Resolve;
1543 Error_Msg_N ("missing explicit dereference in call ", N);
1546 -- If not an access to subprogram, then the prefix must resolve to the
1547 -- name of an entry, entry family, or protected operation.
1549 -- For the case of a simple entry call, P is a selected component where
1550 -- the prefix is the task and the selector name is the entry. A call to
1551 -- a protected procedure will have the same syntax. If the protected
1552 -- object contains overloaded operations, the entity may appear as a
1553 -- function, the context will select the operation whose type is Void.
1555 elsif Nkind (P) = N_Selected_Component
1556 and then Ekind_In (Entity (Selector_Name (P)), E_Entry,
1560 Analyze_Call_And_Resolve;
1562 elsif Nkind (P) = N_Selected_Component
1563 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1564 and then Present (Actuals)
1565 and then No (Next (First (Actuals)))
1567 -- Can be call to parameterless entry family. What appears to be the
1568 -- sole argument is in fact the entry index. Rewrite prefix of node
1569 -- accordingly. Source representation is unchanged by this
1573 Make_Indexed_Component (Loc,
1574 Prefix => New_Copy (P),
1575 Expressions => Actuals);
1576 Set_Name (N, New_N);
1577 Set_Etype (New_N, Standard_Void_Type);
1578 Set_Parameter_Associations (N, No_List);
1579 Analyze_Call_And_Resolve;
1581 -- For the case of a reference to an element of an entry family, P is
1582 -- an indexed component whose prefix is a selected component (task and
1583 -- entry family), and whose index is the entry family index.
1585 elsif Nkind (P) = N_Indexed_Component
1586 and then Nkind (Prefix (P)) = N_Selected_Component
1587 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1589 Analyze_Call_And_Resolve;
1591 -- If the prefix is the name of an entry family, it is a call from
1592 -- within the task body itself.
1594 elsif Nkind (P) = N_Indexed_Component
1595 and then Nkind (Prefix (P)) = N_Identifier
1596 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1599 Make_Selected_Component (Loc,
1600 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1601 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1602 Rewrite (Prefix (P), New_N);
1604 Analyze_Call_And_Resolve;
1606 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1607 -- procedure name, so the construct can only be a qualified expression.
1609 elsif Nkind (P) = N_Qualified_Expression
1610 and then Ada_Version >= Ada_2012
1612 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1615 -- Anything else is an error
1618 Error_Msg_N ("invalid procedure or entry call", N);
1620 end Analyze_Procedure_Call;
1622 ------------------------------
1623 -- Analyze_Return_Statement --
1624 ------------------------------
1626 procedure Analyze_Return_Statement (N : Node_Id) is
1628 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
1629 N_Extended_Return_Statement));
1631 Returns_Object : constant Boolean :=
1632 Nkind (N) = N_Extended_Return_Statement
1634 (Nkind (N) = N_Simple_Return_Statement
1635 and then Present (Expression (N)));
1636 -- True if we're returning something; that is, "return <expression>;"
1637 -- or "return Result : T [:= ...]". False for "return;". Used for error
1638 -- checking: If Returns_Object is True, N should apply to a function
1639 -- body; otherwise N should apply to a procedure body, entry body,
1640 -- accept statement, or extended return statement.
1642 function Find_What_It_Applies_To return Entity_Id;
1643 -- Find the entity representing the innermost enclosing body, accept
1644 -- statement, or extended return statement. If the result is a callable
1645 -- construct or extended return statement, then this will be the value
1646 -- of the Return_Applies_To attribute. Otherwise, the program is
1647 -- illegal. See RM-6.5(4/2).
1649 -----------------------------
1650 -- Find_What_It_Applies_To --
1651 -----------------------------
1653 function Find_What_It_Applies_To return Entity_Id is
1654 Result : Entity_Id := Empty;
1657 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1658 -- and postconditions.
1660 for J in reverse 0 .. Scope_Stack.Last loop
1661 Result := Scope_Stack.Table (J).Entity;
1662 exit when not Ekind_In (Result, E_Block, E_Loop)
1663 and then Chars (Result) /= Name_uPostconditions;
1666 pragma Assert (Present (Result));
1668 end Find_What_It_Applies_To;
1670 -- Local declarations
1672 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1673 Kind : constant Entity_Kind := Ekind (Scope_Id);
1674 Loc : constant Source_Ptr := Sloc (N);
1675 Stm_Entity : constant Entity_Id :=
1677 (E_Return_Statement, Current_Scope, Loc, 'R');
1679 -- Start of processing for Analyze_Return_Statement
1682 Set_Return_Statement_Entity (N, Stm_Entity);
1684 Set_Etype (Stm_Entity, Standard_Void_Type);
1685 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1687 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1688 -- (4/2): an inner return statement will apply to this extended return.
1690 if Nkind (N) = N_Extended_Return_Statement then
1691 Push_Scope (Stm_Entity);
1694 -- Check that pragma No_Return is obeyed. Don't complain about the
1695 -- implicitly-generated return that is placed at the end.
1697 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1698 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1701 -- Warn on any unassigned OUT parameters if in procedure
1703 if Ekind (Scope_Id) = E_Procedure then
1704 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1707 -- Check that functions return objects, and other things do not
1709 if Kind = E_Function or else Kind = E_Generic_Function then
1710 if not Returns_Object then
1711 Error_Msg_N ("missing expression in return from function", N);
1714 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1715 if Returns_Object then
1716 Error_Msg_N ("procedure cannot return value (use function)", N);
1719 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1720 if Returns_Object then
1721 if Is_Protected_Type (Scope (Scope_Id)) then
1722 Error_Msg_N ("entry body cannot return value", N);
1724 Error_Msg_N ("accept statement cannot return value", N);
1728 elsif Kind = E_Return_Statement then
1730 -- We are nested within another return statement, which must be an
1731 -- extended_return_statement.
1733 if Returns_Object then
1734 if Nkind (N) = N_Extended_Return_Statement then
1736 ("extended return statement cannot be nested (use `RETURN;`)",
1739 -- Case of a simple return statement with a value inside extended
1740 -- return statement.
1744 ("return nested in extended return statement cannot return " &
1745 "value (use `RETURN;`)", N);
1750 Error_Msg_N ("illegal context for return statement", N);
1753 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1754 Analyze_Function_Return (N);
1756 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1757 Set_Return_Present (Scope_Id);
1760 if Nkind (N) = N_Extended_Return_Statement then
1764 Kill_Current_Values (Last_Assignment_Only => True);
1765 Check_Unreachable_Code (N);
1767 Analyze_Dimension (N);
1768 end Analyze_Return_Statement;
1770 -------------------------------------
1771 -- Analyze_Simple_Return_Statement --
1772 -------------------------------------
1774 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1776 if Present (Expression (N)) then
1777 Mark_Coextensions (N, Expression (N));
1780 Analyze_Return_Statement (N);
1781 end Analyze_Simple_Return_Statement;
1783 -------------------------
1784 -- Analyze_Return_Type --
1785 -------------------------
1787 procedure Analyze_Return_Type (N : Node_Id) is
1788 Designator : constant Entity_Id := Defining_Entity (N);
1789 Typ : Entity_Id := Empty;
1792 -- Normal case where result definition does not indicate an error
1794 if Result_Definition (N) /= Error then
1795 if Nkind (Result_Definition (N)) = N_Access_Definition then
1796 Check_SPARK_Restriction
1797 ("access result is not allowed", Result_Definition (N));
1799 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1802 AD : constant Node_Id :=
1803 Access_To_Subprogram_Definition (Result_Definition (N));
1805 if Present (AD) and then Protected_Present (AD) then
1806 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1808 Typ := Access_Definition (N, Result_Definition (N));
1812 Set_Parent (Typ, Result_Definition (N));
1813 Set_Is_Local_Anonymous_Access (Typ);
1814 Set_Etype (Designator, Typ);
1816 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1818 Null_Exclusion_Static_Checks (N);
1820 -- Subtype_Mark case
1823 Find_Type (Result_Definition (N));
1824 Typ := Entity (Result_Definition (N));
1825 Set_Etype (Designator, Typ);
1827 -- Unconstrained array as result is not allowed in SPARK
1829 if Is_Array_Type (Typ) and then not Is_Constrained (Typ) then
1830 Check_SPARK_Restriction
1831 ("returning an unconstrained array is not allowed",
1832 Result_Definition (N));
1835 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1837 Null_Exclusion_Static_Checks (N);
1839 -- If a null exclusion is imposed on the result type, then create
1840 -- a null-excluding itype (an access subtype) and use it as the
1841 -- function's Etype. Note that the null exclusion checks are done
1842 -- right before this, because they don't get applied to types that
1843 -- do not come from source.
1845 if Is_Access_Type (Typ) and then Null_Exclusion_Present (N) then
1846 Set_Etype (Designator,
1847 Create_Null_Excluding_Itype
1850 Scope_Id => Scope (Current_Scope)));
1852 -- The new subtype must be elaborated before use because
1853 -- it is visible outside of the function. However its base
1854 -- type may not be frozen yet, so the reference that will
1855 -- force elaboration must be attached to the freezing of
1858 -- If the return specification appears on a proper body,
1859 -- the subtype will have been created already on the spec.
1861 if Is_Frozen (Typ) then
1862 if Nkind (Parent (N)) = N_Subprogram_Body
1863 and then Nkind (Parent (Parent (N))) = N_Subunit
1867 Build_Itype_Reference (Etype (Designator), Parent (N));
1871 Ensure_Freeze_Node (Typ);
1874 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
1876 Set_Itype (IR, Etype (Designator));
1877 Append_Freeze_Actions (Typ, New_List (IR));
1882 Set_Etype (Designator, Typ);
1885 if Ekind (Typ) = E_Incomplete_Type
1886 and then Is_Value_Type (Typ)
1890 elsif Ekind (Typ) = E_Incomplete_Type
1891 or else (Is_Class_Wide_Type (Typ)
1892 and then Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1894 -- AI05-0151: Tagged incomplete types are allowed in all formal
1895 -- parts. Untagged incomplete types are not allowed in bodies.
1897 if Ada_Version >= Ada_2012 then
1898 if Is_Tagged_Type (Typ) then
1901 elsif Nkind_In (Parent (Parent (N)),
1907 ("invalid use of untagged incomplete type&",
1911 -- The type must be completed in the current package. This
1912 -- is checked at the end of the package declaraton, when
1913 -- Taft-amendment types are identified. If the return type
1914 -- is class-wide, there is no required check, the type can
1915 -- be a bona fide TAT.
1917 if Ekind (Scope (Current_Scope)) = E_Package
1918 and then In_Private_Part (Scope (Current_Scope))
1919 and then not Is_Class_Wide_Type (Typ)
1921 Append_Elmt (Designator, Private_Dependents (Typ));
1926 ("invalid use of incomplete type&", Designator, Typ);
1931 -- Case where result definition does indicate an error
1934 Set_Etype (Designator, Any_Type);
1936 end Analyze_Return_Type;
1938 -----------------------------
1939 -- Analyze_Subprogram_Body --
1940 -----------------------------
1942 procedure Analyze_Subprogram_Body (N : Node_Id) is
1943 Loc : constant Source_Ptr := Sloc (N);
1944 Body_Spec : constant Node_Id := Specification (N);
1945 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
1948 if Debug_Flag_C then
1949 Write_Str ("==> subprogram body ");
1950 Write_Name (Chars (Body_Id));
1951 Write_Str (" from ");
1952 Write_Location (Loc);
1957 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1959 -- The real work is split out into the helper, so it can do "return;"
1960 -- without skipping the debug output:
1962 Analyze_Subprogram_Body_Helper (N);
1964 if Debug_Flag_C then
1966 Write_Str ("<== subprogram body ");
1967 Write_Name (Chars (Body_Id));
1968 Write_Str (" from ");
1969 Write_Location (Loc);
1972 end Analyze_Subprogram_Body;
1974 --------------------------------------
1975 -- Analyze_Subprogram_Body_Contract --
1976 --------------------------------------
1978 procedure Analyze_Subprogram_Body_Contract (Body_Id : Entity_Id) is
1979 Body_Decl : constant Node_Id := Parent (Parent (Body_Id));
1980 Spec_Id : constant Entity_Id := Corresponding_Spec (Body_Decl);
1983 Has_Refined_Global : Boolean := False;
1986 -- When a subprogram body declaration is erroneous, its defining entity
1987 -- is left unanalyzed. There is nothing left to do in this case because
1988 -- the body lacks a contract.
1990 if not Analyzed (Body_Id) then
1994 Prag := Classifications (Contract (Body_Id));
1995 while Present (Prag) loop
1996 if Pragma_Name (Prag) = Name_Refined_Depends then
1997 Analyze_Refined_Depends_In_Decl_Part (Prag);
1998 elsif Pragma_Name (Prag) = Name_Refined_Global then
1999 Has_Refined_Global := True;
2000 Analyze_Refined_Global_In_Decl_Part (Prag);
2003 Prag := Next_Pragma (Prag);
2006 -- When the corresponding Global aspect/pragma references a state with
2007 -- visible refinement, the body requires Refined_Global.
2009 if not Has_Refined_Global and then Present (Spec_Id) then
2010 Prag := Get_Pragma (Spec_Id, Pragma_Global);
2012 if Present (Prag) and then Contains_Refined_State (Prag) then
2014 ("body of subprogram & requires global refinement",
2015 Body_Decl, Spec_Id);
2018 end Analyze_Subprogram_Body_Contract;
2020 ------------------------------------
2021 -- Analyze_Subprogram_Body_Helper --
2022 ------------------------------------
2024 -- This procedure is called for regular subprogram bodies, generic bodies,
2025 -- and for subprogram stubs of both kinds. In the case of stubs, only the
2026 -- specification matters, and is used to create a proper declaration for
2027 -- the subprogram, or to perform conformance checks.
2029 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
2030 Loc : constant Source_Ptr := Sloc (N);
2031 Body_Spec : constant Node_Id := Specification (N);
2032 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
2033 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
2034 Conformant : Boolean;
2036 Prot_Typ : Entity_Id := Empty;
2037 Spec_Id : Entity_Id;
2038 Spec_Decl : Node_Id := Empty;
2040 Last_Real_Spec_Entity : Entity_Id := Empty;
2041 -- When we analyze a separate spec, the entity chain ends up containing
2042 -- the formals, as well as any itypes generated during analysis of the
2043 -- default expressions for parameters, or the arguments of associated
2044 -- precondition/postcondition pragmas (which are analyzed in the context
2045 -- of the spec since they have visibility on formals).
2047 -- These entities belong with the spec and not the body. However we do
2048 -- the analysis of the body in the context of the spec (again to obtain
2049 -- visibility to the formals), and all the entities generated during
2050 -- this analysis end up also chained to the entity chain of the spec.
2051 -- But they really belong to the body, and there is circuitry to move
2052 -- them from the spec to the body.
2054 -- However, when we do this move, we don't want to move the real spec
2055 -- entities (first para above) to the body. The Last_Real_Spec_Entity
2056 -- variable points to the last real spec entity, so we only move those
2057 -- chained beyond that point. It is initialized to Empty to deal with
2058 -- the case where there is no separate spec.
2060 procedure Check_Anonymous_Return;
2061 -- Ada 2005: if a function returns an access type that denotes a task,
2062 -- or a type that contains tasks, we must create a master entity for
2063 -- the anonymous type, which typically will be used in an allocator
2064 -- in the body of the function.
2066 procedure Check_Inline_Pragma (Spec : in out Node_Id);
2067 -- Look ahead to recognize a pragma that may appear after the body.
2068 -- If there is a previous spec, check that it appears in the same
2069 -- declarative part. If the pragma is Inline_Always, perform inlining
2070 -- unconditionally, otherwise only if Front_End_Inlining is requested.
2071 -- If the body acts as a spec, and inlining is required, we create a
2072 -- subprogram declaration for it, in order to attach the body to inline.
2073 -- If pragma does not appear after the body, check whether there is
2074 -- an inline pragma before any local declarations.
2076 procedure Check_Missing_Return;
2077 -- Checks for a function with a no return statements, and also performs
2078 -- the warning checks implemented by Check_Returns. In formal mode, also
2079 -- verify that a function ends with a RETURN and that a procedure does
2080 -- not contain any RETURN.
2082 function Disambiguate_Spec return Entity_Id;
2083 -- When a primitive is declared between the private view and the full
2084 -- view of a concurrent type which implements an interface, a special
2085 -- mechanism is used to find the corresponding spec of the primitive
2088 procedure Exchange_Limited_Views (Subp_Id : Entity_Id);
2089 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
2090 -- incomplete types coming from a limited context and swap their limited
2091 -- views with the non-limited ones.
2093 function Is_Private_Concurrent_Primitive
2094 (Subp_Id : Entity_Id) return Boolean;
2095 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
2096 -- type that implements an interface and has a private view.
2098 procedure Set_Trivial_Subprogram (N : Node_Id);
2099 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
2100 -- subprogram whose body is being analyzed. N is the statement node
2101 -- causing the flag to be set, if the following statement is a return
2102 -- of an entity, we mark the entity as set in source to suppress any
2103 -- warning on the stylized use of function stubs with a dummy return.
2105 procedure Verify_Overriding_Indicator;
2106 -- If there was a previous spec, the entity has been entered in the
2107 -- current scope previously. If the body itself carries an overriding
2108 -- indicator, check that it is consistent with the known status of the
2111 ----------------------------
2112 -- Check_Anonymous_Return --
2113 ----------------------------
2115 procedure Check_Anonymous_Return is
2121 if Present (Spec_Id) then
2127 if Ekind (Scop) = E_Function
2128 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
2129 and then not Is_Thunk (Scop)
2130 and then (Has_Task (Designated_Type (Etype (Scop)))
2132 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
2134 Is_Limited_Record (Designated_Type (Etype (Scop)))))
2135 and then Expander_Active
2137 -- Avoid cases with no tasking support
2139 and then RTE_Available (RE_Current_Master)
2140 and then not Restriction_Active (No_Task_Hierarchy)
2143 Make_Object_Declaration (Loc,
2144 Defining_Identifier =>
2145 Make_Defining_Identifier (Loc, Name_uMaster),
2146 Constant_Present => True,
2147 Object_Definition =>
2148 New_Reference_To (RTE (RE_Master_Id), Loc),
2150 Make_Explicit_Dereference (Loc,
2151 New_Reference_To (RTE (RE_Current_Master), Loc)));
2153 if Present (Declarations (N)) then
2154 Prepend (Decl, Declarations (N));
2156 Set_Declarations (N, New_List (Decl));
2159 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
2160 Set_Has_Master_Entity (Scop);
2162 -- Now mark the containing scope as a task master
2165 while Nkind (Par) /= N_Compilation_Unit loop
2166 Par := Parent (Par);
2167 pragma Assert (Present (Par));
2169 -- If we fall off the top, we are at the outer level, and
2170 -- the environment task is our effective master, so nothing
2174 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
2176 Set_Is_Task_Master (Par, True);
2181 end Check_Anonymous_Return;
2183 -------------------------
2184 -- Check_Inline_Pragma --
2185 -------------------------
2187 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
2191 function Is_Inline_Pragma (N : Node_Id) return Boolean;
2192 -- True when N is a pragma Inline or Inline_Always that applies
2193 -- to this subprogram.
2195 -----------------------
2196 -- Is_Inline_Pragma --
2197 -----------------------
2199 function Is_Inline_Pragma (N : Node_Id) return Boolean is
2202 Nkind (N) = N_Pragma
2204 (Pragma_Name (N) = Name_Inline_Always
2207 and then Pragma_Name (N) = Name_Inline))
2210 (Expression (First (Pragma_Argument_Associations (N)))) =
2212 end Is_Inline_Pragma;
2214 -- Start of processing for Check_Inline_Pragma
2217 if not Expander_Active then
2221 if Is_List_Member (N)
2222 and then Present (Next (N))
2223 and then Is_Inline_Pragma (Next (N))
2227 elsif Nkind (N) /= N_Subprogram_Body_Stub
2228 and then Present (Declarations (N))
2229 and then Is_Inline_Pragma (First (Declarations (N)))
2231 Prag := First (Declarations (N));
2237 if Present (Prag) then
2238 if Present (Spec_Id) then
2239 if In_Same_List (N, Unit_Declaration_Node (Spec_Id)) then
2244 -- Create a subprogram declaration, to make treatment uniform
2247 Subp : constant Entity_Id :=
2248 Make_Defining_Identifier (Loc, Chars (Body_Id));
2249 Decl : constant Node_Id :=
2250 Make_Subprogram_Declaration (Loc,
2252 New_Copy_Tree (Specification (N)));
2255 Set_Defining_Unit_Name (Specification (Decl), Subp);
2257 if Present (First_Formal (Body_Id)) then
2258 Plist := Copy_Parameter_List (Body_Id);
2259 Set_Parameter_Specifications
2260 (Specification (Decl), Plist);
2263 Insert_Before (N, Decl);
2266 Set_Has_Pragma_Inline (Subp);
2268 if Pragma_Name (Prag) = Name_Inline_Always then
2269 Set_Is_Inlined (Subp);
2270 Set_Has_Pragma_Inline_Always (Subp);
2277 end Check_Inline_Pragma;
2279 --------------------------
2280 -- Check_Missing_Return --
2281 --------------------------
2283 procedure Check_Missing_Return is
2285 Missing_Ret : Boolean;
2288 if Nkind (Body_Spec) = N_Function_Specification then
2289 if Present (Spec_Id) then
2295 if Return_Present (Id) then
2296 Check_Returns (HSS, 'F', Missing_Ret);
2299 Set_Has_Missing_Return (Id);
2302 elsif Is_Generic_Subprogram (Id)
2303 or else not Is_Machine_Code_Subprogram (Id)
2305 Error_Msg_N ("missing RETURN statement in function body", N);
2308 -- If procedure with No_Return, check returns
2310 elsif Nkind (Body_Spec) = N_Procedure_Specification
2311 and then Present (Spec_Id)
2312 and then No_Return (Spec_Id)
2314 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2317 -- Special checks in SPARK mode
2319 if Nkind (Body_Spec) = N_Function_Specification then
2321 -- In SPARK mode, last statement of a function should be a return
2324 Stat : constant Node_Id := Last_Source_Statement (HSS);
2327 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2328 N_Extended_Return_Statement)
2330 Check_SPARK_Restriction
2331 ("last statement in function should be RETURN", Stat);
2335 -- In SPARK mode, verify that a procedure has no return
2337 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2338 if Present (Spec_Id) then
2344 -- Would be nice to point to return statement here, can we
2345 -- borrow the Check_Returns procedure here ???
2347 if Return_Present (Id) then
2348 Check_SPARK_Restriction
2349 ("procedure should not have RETURN", N);
2352 end Check_Missing_Return;
2354 -----------------------
2355 -- Disambiguate_Spec --
2356 -----------------------
2358 function Disambiguate_Spec return Entity_Id is
2359 Priv_Spec : Entity_Id;
2362 procedure Replace_Types (To_Corresponding : Boolean);
2363 -- Depending on the flag, replace the type of formal parameters of
2364 -- Body_Id if it is a concurrent type implementing interfaces with
2365 -- the corresponding record type or the other way around.
2367 procedure Replace_Types (To_Corresponding : Boolean) is
2369 Formal_Typ : Entity_Id;
2372 Formal := First_Formal (Body_Id);
2373 while Present (Formal) loop
2374 Formal_Typ := Etype (Formal);
2376 if Is_Class_Wide_Type (Formal_Typ) then
2377 Formal_Typ := Root_Type (Formal_Typ);
2380 -- From concurrent type to corresponding record
2382 if To_Corresponding then
2383 if Is_Concurrent_Type (Formal_Typ)
2384 and then Present (Corresponding_Record_Type (Formal_Typ))
2385 and then Present (Interfaces (
2386 Corresponding_Record_Type (Formal_Typ)))
2389 Corresponding_Record_Type (Formal_Typ));
2392 -- From corresponding record to concurrent type
2395 if Is_Concurrent_Record_Type (Formal_Typ)
2396 and then Present (Interfaces (Formal_Typ))
2399 Corresponding_Concurrent_Type (Formal_Typ));
2403 Next_Formal (Formal);
2407 -- Start of processing for Disambiguate_Spec
2410 -- Try to retrieve the specification of the body as is. All error
2411 -- messages are suppressed because the body may not have a spec in
2412 -- its current state.
2414 Spec_N := Find_Corresponding_Spec (N, False);
2416 -- It is possible that this is the body of a primitive declared
2417 -- between a private and a full view of a concurrent type. The
2418 -- controlling parameter of the spec carries the concurrent type,
2419 -- not the corresponding record type as transformed by Analyze_
2420 -- Subprogram_Specification. In such cases, we undo the change
2421 -- made by the analysis of the specification and try to find the
2424 -- Note that wrappers already have their corresponding specs and
2425 -- bodies set during their creation, so if the candidate spec is
2426 -- a wrapper, then we definitely need to swap all types to their
2427 -- original concurrent status.
2430 or else Is_Primitive_Wrapper (Spec_N)
2432 -- Restore all references of corresponding record types to the
2433 -- original concurrent types.
2435 Replace_Types (To_Corresponding => False);
2436 Priv_Spec := Find_Corresponding_Spec (N, False);
2438 -- The current body truly belongs to a primitive declared between
2439 -- a private and a full view. We leave the modified body as is,
2440 -- and return the true spec.
2442 if Present (Priv_Spec)
2443 and then Is_Private_Primitive (Priv_Spec)
2448 -- In case that this is some sort of error, restore the original
2449 -- state of the body.
2451 Replace_Types (To_Corresponding => True);
2455 end Disambiguate_Spec;
2457 ----------------------------
2458 -- Exchange_Limited_Views --
2459 ----------------------------
2461 procedure Exchange_Limited_Views (Subp_Id : Entity_Id) is
2462 procedure Detect_And_Exchange (Id : Entity_Id);
2463 -- Determine whether Id's type denotes an incomplete type associated
2464 -- with a limited with clause and exchange the limited view with the
2467 -------------------------
2468 -- Detect_And_Exchange --
2469 -------------------------
2471 procedure Detect_And_Exchange (Id : Entity_Id) is
2472 Typ : constant Entity_Id := Etype (Id);
2475 if Ekind (Typ) = E_Incomplete_Type
2476 and then From_With_Type (Typ)
2477 and then Present (Non_Limited_View (Typ))
2479 Set_Etype (Id, Non_Limited_View (Typ));
2481 end Detect_And_Exchange;
2487 -- Start of processing for Exchange_Limited_Views
2490 if No (Subp_Id) then
2493 -- Do not process subprogram bodies as they already use the non-
2494 -- limited view of types.
2496 elsif not Ekind_In (Subp_Id, E_Function, E_Procedure) then
2500 -- Examine all formals and swap views when applicable
2502 Formal := First_Formal (Subp_Id);
2503 while Present (Formal) loop
2504 Detect_And_Exchange (Formal);
2506 Next_Formal (Formal);
2509 -- Process the return type of a function
2511 if Ekind (Subp_Id) = E_Function then
2512 Detect_And_Exchange (Subp_Id);
2514 end Exchange_Limited_Views;
2516 -------------------------------------
2517 -- Is_Private_Concurrent_Primitive --
2518 -------------------------------------
2520 function Is_Private_Concurrent_Primitive
2521 (Subp_Id : Entity_Id) return Boolean
2523 Formal_Typ : Entity_Id;
2526 if Present (First_Formal (Subp_Id)) then
2527 Formal_Typ := Etype (First_Formal (Subp_Id));
2529 if Is_Concurrent_Record_Type (Formal_Typ) then
2530 if Is_Class_Wide_Type (Formal_Typ) then
2531 Formal_Typ := Root_Type (Formal_Typ);
2534 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
2537 -- The type of the first formal is a concurrent tagged type with
2541 Is_Concurrent_Type (Formal_Typ)
2542 and then Is_Tagged_Type (Formal_Typ)
2543 and then Has_Private_Declaration (Formal_Typ);
2547 end Is_Private_Concurrent_Primitive;
2549 ----------------------------
2550 -- Set_Trivial_Subprogram --
2551 ----------------------------
2553 procedure Set_Trivial_Subprogram (N : Node_Id) is
2554 Nxt : constant Node_Id := Next (N);
2557 Set_Is_Trivial_Subprogram (Body_Id);
2559 if Present (Spec_Id) then
2560 Set_Is_Trivial_Subprogram (Spec_Id);
2564 and then Nkind (Nxt) = N_Simple_Return_Statement
2565 and then No (Next (Nxt))
2566 and then Present (Expression (Nxt))
2567 and then Is_Entity_Name (Expression (Nxt))
2569 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
2571 end Set_Trivial_Subprogram;
2573 ---------------------------------
2574 -- Verify_Overriding_Indicator --
2575 ---------------------------------
2577 procedure Verify_Overriding_Indicator is
2579 if Must_Override (Body_Spec) then
2580 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
2581 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2585 elsif not Present (Overridden_Operation (Spec_Id)) then
2587 ("subprogram& is not overriding", Body_Spec, Spec_Id);
2590 elsif Must_Not_Override (Body_Spec) then
2591 if Present (Overridden_Operation (Spec_Id)) then
2593 ("subprogram& overrides inherited operation",
2594 Body_Spec, Spec_Id);
2596 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
2597 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2600 ("subprogram & overrides predefined operator ",
2601 Body_Spec, Spec_Id);
2603 -- If this is not a primitive operation or protected subprogram,
2604 -- then the overriding indicator is altogether illegal.
2606 elsif not Is_Primitive (Spec_Id)
2607 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
2610 ("overriding indicator only allowed " &
2611 "if subprogram is primitive",
2616 and then Present (Overridden_Operation (Spec_Id))
2618 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2619 Style.Missing_Overriding (N, Body_Id);
2622 and then Can_Override_Operator (Spec_Id)
2623 and then not Is_Predefined_File_Name
2624 (Unit_File_Name (Get_Source_Unit (Spec_Id)))
2626 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2627 Style.Missing_Overriding (N, Body_Id);
2629 end Verify_Overriding_Indicator;
2631 -- Start of processing for Analyze_Subprogram_Body_Helper
2634 -- Generic subprograms are handled separately. They always have a
2635 -- generic specification. Determine whether current scope has a
2636 -- previous declaration.
2638 -- If the subprogram body is defined within an instance of the same
2639 -- name, the instance appears as a package renaming, and will be hidden
2640 -- within the subprogram.
2642 if Present (Prev_Id)
2643 and then not Is_Overloadable (Prev_Id)
2644 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
2645 or else Comes_From_Source (Prev_Id))
2647 if Is_Generic_Subprogram (Prev_Id) then
2649 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2650 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2652 Analyze_Generic_Subprogram_Body (N, Spec_Id);
2654 if Nkind (N) = N_Subprogram_Body then
2655 HSS := Handled_Statement_Sequence (N);
2656 Check_Missing_Return;
2662 -- Previous entity conflicts with subprogram name. Attempting to
2663 -- enter name will post error.
2665 Enter_Name (Body_Id);
2669 -- Non-generic case, find the subprogram declaration, if one was seen,
2670 -- or enter new overloaded entity in the current scope. If the
2671 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
2672 -- part of the context of one of its subunits. No need to redo the
2675 elsif Prev_Id = Body_Id and then Has_Completion (Body_Id) then
2679 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2681 if Nkind (N) = N_Subprogram_Body_Stub
2682 or else No (Corresponding_Spec (N))
2684 if Is_Private_Concurrent_Primitive (Body_Id) then
2685 Spec_Id := Disambiguate_Spec;
2687 Spec_Id := Find_Corresponding_Spec (N);
2690 -- If this is a duplicate body, no point in analyzing it
2692 if Error_Posted (N) then
2696 -- A subprogram body should cause freezing of its own declaration,
2697 -- but if there was no previous explicit declaration, then the
2698 -- subprogram will get frozen too late (there may be code within
2699 -- the body that depends on the subprogram having been frozen,
2700 -- such as uses of extra formals), so we force it to be frozen
2701 -- here. Same holds if the body and spec are compilation units.
2702 -- Finally, if the return type is an anonymous access to protected
2703 -- subprogram, it must be frozen before the body because its
2704 -- expansion has generated an equivalent type that is used when
2705 -- elaborating the body.
2707 -- An exception in the case of Ada 2012, AI05-177: The bodies
2708 -- created for expression functions do not freeze.
2711 and then Nkind (Original_Node (N)) /= N_Expression_Function
2713 Freeze_Before (N, Body_Id);
2715 elsif Nkind (Parent (N)) = N_Compilation_Unit then
2716 Freeze_Before (N, Spec_Id);
2718 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
2719 Freeze_Before (N, Etype (Body_Id));
2723 Spec_Id := Corresponding_Spec (N);
2727 -- Language-defined aspects cannot appear in a subprogram body [stub] if
2728 -- the subprogram has a separate spec. Certainly implementation-defined
2729 -- aspects are allowed to appear (per Aspects_On_Body_Of_Stub_OK).
2731 if Has_Aspects (N) then
2732 if Present (Spec_Id)
2733 and then not Aspects_On_Body_Or_Stub_OK (N)
2735 -- Do not emit an error on a subprogram body stub that act as
2738 and then Nkind (Parent (Parent (Spec_Id))) /= N_Subprogram_Body_Stub
2741 ("aspect specifications must appear in subprogram declaration",
2744 -- Delay the analysis of aspect specifications that apply to a body
2745 -- stub until the proper body is analyzed. If the corresponding body
2746 -- is missing, the aspects are still analyzed in Analyze_Proper_Body.
2748 elsif Nkind (N) in N_Body_Stub then
2752 Analyze_Aspect_Specifications (N, Body_Id);
2756 -- Previously we scanned the body to look for nested subprograms, and
2757 -- rejected an inline directive if nested subprograms were present,
2758 -- because the back-end would generate conflicting symbols for the
2759 -- nested bodies. This is now unnecessary.
2761 -- Look ahead to recognize a pragma Inline that appears after the body
2763 Check_Inline_Pragma (Spec_Id);
2765 -- Deal with special case of a fully private operation in the body of
2766 -- the protected type. We must create a declaration for the subprogram,
2767 -- in order to attach the protected subprogram that will be used in
2768 -- internal calls. We exclude compiler generated bodies from the
2769 -- expander since the issue does not arise for those cases.
2772 and then Comes_From_Source (N)
2773 and then Is_Protected_Type (Current_Scope)
2775 Spec_Id := Build_Private_Protected_Declaration (N);
2778 -- If a separate spec is present, then deal with freezing issues
2780 if Present (Spec_Id) then
2781 Spec_Decl := Unit_Declaration_Node (Spec_Id);
2782 Verify_Overriding_Indicator;
2784 -- In general, the spec will be frozen when we start analyzing the
2785 -- body. However, for internally generated operations, such as
2786 -- wrapper functions for inherited operations with controlling
2787 -- results, the spec may not have been frozen by the time we expand
2788 -- the freeze actions that include the bodies. In particular, extra
2789 -- formals for accessibility or for return-in-place may need to be
2790 -- generated. Freeze nodes, if any, are inserted before the current
2791 -- body. These freeze actions are also needed in ASIS mode to enable
2792 -- the proper back-annotations.
2794 if not Is_Frozen (Spec_Id)
2795 and then (Expander_Active or ASIS_Mode)
2797 -- Force the generation of its freezing node to ensure proper
2798 -- management of access types in the backend.
2800 -- This is definitely needed for some cases, but it is not clear
2801 -- why, to be investigated further???
2803 Set_Has_Delayed_Freeze (Spec_Id);
2804 Freeze_Before (N, Spec_Id);
2808 -- Mark presence of postcondition procedure in current scope and mark
2809 -- the procedure itself as needing debug info. The latter is important
2810 -- when analyzing decision coverage (for example, for MC/DC coverage).
2812 if Chars (Body_Id) = Name_uPostconditions then
2813 Set_Has_Postconditions (Current_Scope);
2814 Set_Debug_Info_Needed (Body_Id);
2817 -- Place subprogram on scope stack, and make formals visible. If there
2818 -- is a spec, the visible entity remains that of the spec.
2820 if Present (Spec_Id) then
2821 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
2823 if Is_Child_Unit (Spec_Id) then
2824 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
2828 Style.Check_Identifier (Body_Id, Spec_Id);
2831 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2832 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2834 if Is_Abstract_Subprogram (Spec_Id) then
2835 Error_Msg_N ("an abstract subprogram cannot have a body", N);
2839 Set_Convention (Body_Id, Convention (Spec_Id));
2840 Set_Has_Completion (Spec_Id);
2842 if Is_Protected_Type (Scope (Spec_Id)) then
2843 Prot_Typ := Scope (Spec_Id);
2846 -- If this is a body generated for a renaming, do not check for
2847 -- full conformance. The check is redundant, because the spec of
2848 -- the body is a copy of the spec in the renaming declaration,
2849 -- and the test can lead to spurious errors on nested defaults.
2851 if Present (Spec_Decl)
2852 and then not Comes_From_Source (N)
2854 (Nkind (Original_Node (Spec_Decl)) =
2855 N_Subprogram_Renaming_Declaration
2856 or else (Present (Corresponding_Body (Spec_Decl))
2858 Nkind (Unit_Declaration_Node
2859 (Corresponding_Body (Spec_Decl))) =
2860 N_Subprogram_Renaming_Declaration))
2864 -- Conversely, the spec may have been generated for specless body
2865 -- with an inline pragma.
2867 elsif Comes_From_Source (N)
2868 and then not Comes_From_Source (Spec_Id)
2869 and then Has_Pragma_Inline (Spec_Id)
2876 Fully_Conformant, True, Conformant, Body_Id);
2879 -- If the body is not fully conformant, we have to decide if we
2880 -- should analyze it or not. If it has a really messed up profile
2881 -- then we probably should not analyze it, since we will get too
2882 -- many bogus messages.
2884 -- Our decision is to go ahead in the non-fully conformant case
2885 -- only if it is at least mode conformant with the spec. Note
2886 -- that the call to Check_Fully_Conformant has issued the proper
2887 -- error messages to complain about the lack of conformance.
2890 and then not Mode_Conformant (Body_Id, Spec_Id)
2896 if Spec_Id /= Body_Id then
2897 Reference_Body_Formals (Spec_Id, Body_Id);
2900 if Nkind (N) = N_Subprogram_Body_Stub then
2901 Set_Corresponding_Spec_Of_Stub (N, Spec_Id);
2906 Set_Corresponding_Spec (N, Spec_Id);
2908 -- Ada 2005 (AI-345): If the operation is a primitive operation
2909 -- of a concurrent type, the type of the first parameter has been
2910 -- replaced with the corresponding record, which is the proper
2911 -- run-time structure to use. However, within the body there may
2912 -- be uses of the formals that depend on primitive operations
2913 -- of the type (in particular calls in prefixed form) for which
2914 -- we need the original concurrent type. The operation may have
2915 -- several controlling formals, so the replacement must be done
2918 if Comes_From_Source (Spec_Id)
2919 and then Present (First_Entity (Spec_Id))
2920 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2921 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2922 and then Present (Interfaces (Etype (First_Entity (Spec_Id))))
2923 and then Present (Corresponding_Concurrent_Type
2924 (Etype (First_Entity (Spec_Id))))
2927 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2931 Form := First_Formal (Spec_Id);
2932 while Present (Form) loop
2933 if Etype (Form) = Typ then
2934 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2942 -- Make the formals visible, and place subprogram on scope stack.
2943 -- This is also the point at which we set Last_Real_Spec_Entity
2944 -- to mark the entities which will not be moved to the body.
2946 Install_Formals (Spec_Id);
2947 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2949 -- Within an instance, add local renaming declarations so that
2950 -- gdb can retrieve the values of actuals more easily. This is
2951 -- only relevant if generating code (and indeed we definitely
2952 -- do not want these definitions -gnatc mode, because that would
2955 if Is_Generic_Instance (Spec_Id)
2956 and then Is_Wrapper_Package (Current_Scope)
2957 and then Expander_Active
2959 Build_Subprogram_Instance_Renamings (N, Current_Scope);
2962 Push_Scope (Spec_Id);
2964 -- Make sure that the subprogram is immediately visible. For
2965 -- child units that have no separate spec this is indispensable.
2966 -- Otherwise it is safe albeit redundant.
2968 Set_Is_Immediately_Visible (Spec_Id);
2971 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2972 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
2973 Set_Ekind (Body_Id, E_Subprogram_Body);
2974 Set_Scope (Body_Id, Scope (Spec_Id));
2975 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2977 -- Case of subprogram body with no previous spec
2980 -- Check for style warning required
2984 -- Only apply check for source level subprograms for which checks
2985 -- have not been suppressed.
2987 and then Comes_From_Source (Body_Id)
2988 and then not Suppress_Style_Checks (Body_Id)
2990 -- No warnings within an instance
2992 and then not In_Instance
2994 -- No warnings for expression functions
2996 and then Nkind (Original_Node (N)) /= N_Expression_Function
2998 Style.Body_With_No_Spec (N);
3001 New_Overloaded_Entity (Body_Id);
3003 if Nkind (N) /= N_Subprogram_Body_Stub then
3004 Set_Acts_As_Spec (N);
3005 Generate_Definition (Body_Id);
3006 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
3008 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
3009 Install_Formals (Body_Id);
3010 Push_Scope (Body_Id);
3013 -- For stubs and bodies with no previous spec, generate references to
3016 Generate_Reference_To_Formals (Body_Id);
3019 -- If the return type is an anonymous access type whose designated type
3020 -- is the limited view of a class-wide type and the non-limited view is
3021 -- available, update the return type accordingly.
3023 if Ada_Version >= Ada_2005 and then Comes_From_Source (N) then
3029 Rtyp := Etype (Current_Scope);
3031 if Ekind (Rtyp) = E_Anonymous_Access_Type then
3032 Etyp := Directly_Designated_Type (Rtyp);
3034 if Is_Class_Wide_Type (Etyp) and then From_With_Type (Etyp) then
3035 Set_Directly_Designated_Type
3036 (Etype (Current_Scope), Available_View (Etyp));
3042 -- If this is the proper body of a stub, we must verify that the stub
3043 -- conforms to the body, and to the previous spec if one was present.
3044 -- We know already that the body conforms to that spec. This test is
3045 -- only required for subprograms that come from source.
3047 if Nkind (Parent (N)) = N_Subunit
3048 and then Comes_From_Source (N)
3049 and then not Error_Posted (Body_Id)
3050 and then Nkind (Corresponding_Stub (Parent (N))) =
3051 N_Subprogram_Body_Stub
3054 Old_Id : constant Entity_Id :=
3056 (Specification (Corresponding_Stub (Parent (N))));
3058 Conformant : Boolean := False;
3061 if No (Spec_Id) then
3062 Check_Fully_Conformant (Body_Id, Old_Id);
3066 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
3068 if not Conformant then
3070 -- The stub was taken to be a new declaration. Indicate that
3073 Set_Has_Completion (Old_Id, False);
3079 Set_Has_Completion (Body_Id);
3080 Check_Eliminated (Body_Id);
3082 if Nkind (N) = N_Subprogram_Body_Stub then
3086 -- Handle frontend inlining. There is no need to prepare us for inlining
3087 -- if we will not generate the code.
3091 if not Debug_Flag_Dot_K then
3092 if Present (Spec_Id)
3093 and then Expander_Active
3095 (Has_Pragma_Inline_Always (Spec_Id)
3096 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
3098 Build_Body_To_Inline (N, Spec_Id);
3103 elsif Expander_Active
3104 and then Serious_Errors_Detected = 0
3105 and then Present (Spec_Id)
3106 and then Has_Pragma_Inline (Spec_Id)
3108 Check_And_Build_Body_To_Inline (N, Spec_Id, Body_Id);
3111 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
3112 -- of the specification we have to install the private withed units.
3113 -- This holds for child units as well.
3115 if Is_Compilation_Unit (Body_Id)
3116 or else Nkind (Parent (N)) = N_Compilation_Unit
3118 Install_Private_With_Clauses (Body_Id);
3121 Check_Anonymous_Return;
3123 -- Set the Protected_Formal field of each extra formal of the protected
3124 -- subprogram to reference the corresponding extra formal of the
3125 -- subprogram that implements it. For regular formals this occurs when
3126 -- the protected subprogram's declaration is expanded, but the extra
3127 -- formals don't get created until the subprogram is frozen. We need to
3128 -- do this before analyzing the protected subprogram's body so that any
3129 -- references to the original subprogram's extra formals will be changed
3130 -- refer to the implementing subprogram's formals (see Expand_Formal).
3132 if Present (Spec_Id)
3133 and then Is_Protected_Type (Scope (Spec_Id))
3134 and then Present (Protected_Body_Subprogram (Spec_Id))
3137 Impl_Subp : constant Entity_Id :=
3138 Protected_Body_Subprogram (Spec_Id);
3139 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
3140 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
3142 while Present (Prot_Ext_Formal) loop
3143 pragma Assert (Present (Impl_Ext_Formal));
3144 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
3145 Next_Formal_With_Extras (Prot_Ext_Formal);
3146 Next_Formal_With_Extras (Impl_Ext_Formal);
3151 -- Now we can go on to analyze the body
3153 HSS := Handled_Statement_Sequence (N);
3154 Set_Actual_Subtypes (N, Current_Scope);
3156 -- Deal with [refined] preconditions, postconditions, Contract_Cases,
3157 -- invariants and predicates associated with the body and its spec.
3158 -- Note that this is not pure expansion as Expand_Subprogram_Contract
3159 -- prepares the contract assertions for generic subprograms or for ASIS.
3160 -- Do not generate contract checks in SPARK mode.
3162 if not SPARK_Mode then
3163 Expand_Subprogram_Contract (N, Spec_Id, Body_Id);
3166 -- Add a declaration for the Protection object, renaming declarations
3167 -- for discriminals and privals and finally a declaration for the entry
3168 -- family index (if applicable). This form of early expansion is done
3169 -- when the Expander is active because Install_Private_Data_Declarations
3170 -- references entities which were created during regular expansion. The
3171 -- body may be the rewritting of an expression function, and we need to
3172 -- verify that the original node is in the source.
3174 if Full_Expander_Active
3175 and then Comes_From_Source (Original_Node (N))
3176 and then Present (Prot_Typ)
3177 and then Present (Spec_Id)
3178 and then not Is_Eliminated (Spec_Id)
3180 Install_Private_Data_Declarations
3181 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
3184 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
3185 -- may now appear in parameter and result profiles. Since the analysis
3186 -- of a subprogram body may use the parameter and result profile of the
3187 -- spec, swap any limited views with their non-limited counterpart.
3189 if Ada_Version >= Ada_2012 then
3190 Exchange_Limited_Views (Spec_Id);
3193 -- Analyze the declarations (this call will analyze the precondition
3194 -- Check pragmas we prepended to the list, as well as the declaration
3195 -- of the _Postconditions procedure).
3197 Analyze_Declarations (Declarations (N));
3199 -- Check completion, and analyze the statements
3202 Inspect_Deferred_Constant_Completion (Declarations (N));
3205 -- Deal with end of scope processing for the body
3207 Process_End_Label (HSS, 't', Current_Scope);
3209 Check_Subprogram_Order (N);
3210 Set_Analyzed (Body_Id);
3212 -- If we have a separate spec, then the analysis of the declarations
3213 -- caused the entities in the body to be chained to the spec id, but
3214 -- we want them chained to the body id. Only the formal parameters
3215 -- end up chained to the spec id in this case.
3217 if Present (Spec_Id) then
3219 -- We must conform to the categorization of our spec
3221 Validate_Categorization_Dependency (N, Spec_Id);
3223 -- And if this is a child unit, the parent units must conform
3225 if Is_Child_Unit (Spec_Id) then
3226 Validate_Categorization_Dependency
3227 (Unit_Declaration_Node (Spec_Id), Spec_Id);
3230 -- Here is where we move entities from the spec to the body
3232 -- Case where there are entities that stay with the spec
3234 if Present (Last_Real_Spec_Entity) then
3236 -- No body entities (happens when the only real spec entities come
3237 -- from precondition and postcondition pragmas).
3239 if No (Last_Entity (Body_Id)) then
3241 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
3243 -- Body entities present (formals), so chain stuff past them
3247 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
3250 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
3251 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
3252 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
3254 -- Case where there are no spec entities, in this case there can be
3255 -- no body entities either, so just move everything.
3258 pragma Assert (No (Last_Entity (Body_Id)));
3259 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
3260 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
3261 Set_First_Entity (Spec_Id, Empty);
3262 Set_Last_Entity (Spec_Id, Empty);
3266 Check_Missing_Return;
3268 -- Now we are going to check for variables that are never modified in
3269 -- the body of the procedure. But first we deal with a special case
3270 -- where we want to modify this check. If the body of the subprogram
3271 -- starts with a raise statement or its equivalent, or if the body
3272 -- consists entirely of a null statement, then it is pretty obvious
3273 -- that it is OK to not reference the parameters. For example, this
3274 -- might be the following common idiom for a stubbed function:
3275 -- statement of the procedure raises an exception. In particular this
3276 -- deals with the common idiom of a stubbed function, which might
3277 -- appear as something like:
3279 -- function F (A : Integer) return Some_Type;
3282 -- raise Program_Error;
3286 -- Here the purpose of X is simply to satisfy the annoying requirement
3287 -- in Ada that there be at least one return, and we certainly do not
3288 -- want to go posting warnings on X that it is not initialized! On
3289 -- the other hand, if X is entirely unreferenced that should still
3292 -- What we do is to detect these cases, and if we find them, flag the
3293 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
3294 -- suppress unwanted warnings. For the case of the function stub above
3295 -- we have a special test to set X as apparently assigned to suppress
3302 -- Skip initial labels (for one thing this occurs when we are in
3303 -- front end ZCX mode, but in any case it is irrelevant), and also
3304 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
3306 Stm := First (Statements (HSS));
3307 while Nkind (Stm) = N_Label
3308 or else Nkind (Stm) in N_Push_xxx_Label
3313 -- Do the test on the original statement before expansion
3316 Ostm : constant Node_Id := Original_Node (Stm);
3319 -- If explicit raise statement, turn on flag
3321 if Nkind (Ostm) = N_Raise_Statement then
3322 Set_Trivial_Subprogram (Stm);
3324 -- If null statement, and no following statements, turn on flag
3326 elsif Nkind (Stm) = N_Null_Statement
3327 and then Comes_From_Source (Stm)
3328 and then No (Next (Stm))
3330 Set_Trivial_Subprogram (Stm);
3332 -- Check for explicit call cases which likely raise an exception
3334 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
3335 if Is_Entity_Name (Name (Ostm)) then
3337 Ent : constant Entity_Id := Entity (Name (Ostm));
3340 -- If the procedure is marked No_Return, then likely it
3341 -- raises an exception, but in any case it is not coming
3342 -- back here, so turn on the flag.
3345 and then Ekind (Ent) = E_Procedure
3346 and then No_Return (Ent)
3348 Set_Trivial_Subprogram (Stm);
3356 -- Check for variables that are never modified
3362 -- If there is a separate spec, then transfer Never_Set_In_Source
3363 -- flags from out parameters to the corresponding entities in the
3364 -- body. The reason we do that is we want to post error flags on
3365 -- the body entities, not the spec entities.
3367 if Present (Spec_Id) then
3368 E1 := First_Entity (Spec_Id);
3369 while Present (E1) loop
3370 if Ekind (E1) = E_Out_Parameter then
3371 E2 := First_Entity (Body_Id);
3372 while Present (E2) loop
3373 exit when Chars (E1) = Chars (E2);
3377 if Present (E2) then
3378 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
3386 -- Check references in body
3388 Check_References (Body_Id);
3390 end Analyze_Subprogram_Body_Helper;
3392 ---------------------------------
3393 -- Analyze_Subprogram_Contract --
3394 ---------------------------------
3396 procedure Analyze_Subprogram_Contract (Subp : Entity_Id) is
3397 Result_Seen : Boolean := False;
3398 -- A flag which keeps track of whether at least one postcondition or
3399 -- contract-case mentions attribute 'Result (set True if so).
3401 procedure Check_Result_And_Post_State
3403 Error_Nod : in out Node_Id);
3404 -- Determine whether pragma Prag mentions attribute 'Result and whether
3405 -- the pragma contains an expression that evaluates differently in pre-
3406 -- and post-state. Prag is a postcondition or a contract-cases pragma.
3407 -- Error_Nod denotes the proper error node.
3409 ---------------------------------
3410 -- Check_Result_And_Post_State --
3411 ---------------------------------
3413 procedure Check_Result_And_Post_State
3415 Error_Nod : in out Node_Id)
3417 procedure Check_Expression (Expr : Node_Id);
3418 -- Perform the 'Result and post-state checks on a given expression
3420 function Is_Function_Result (N : Node_Id) return Traverse_Result;
3421 -- Attempt to find attribute 'Result in a subtree denoted by N
3423 function Is_Trivial_Boolean (N : Node_Id) return Boolean;
3424 -- Determine whether source node N denotes "True" or "False"
3426 function Mentions_Post_State (N : Node_Id) return Boolean;
3427 -- Determine whether a subtree denoted by N mentions any construct
3428 -- that denotes a post-state.
3430 procedure Check_Function_Result is
3431 new Traverse_Proc (Is_Function_Result);
3433 ----------------------
3434 -- Check_Expression --
3435 ----------------------
3437 procedure Check_Expression (Expr : Node_Id) is
3439 if not Is_Trivial_Boolean (Expr) then
3440 Check_Function_Result (Expr);
3442 if not Mentions_Post_State (Expr) then
3443 if Pragma_Name (Prag) = Name_Contract_Cases then
3445 ("contract case refers only to pre-state?T?", Expr);
3448 ("postcondition refers only to pre-state?T?", Prag);
3452 end Check_Expression;
3454 ------------------------
3455 -- Is_Function_Result --
3456 ------------------------
3458 function Is_Function_Result (N : Node_Id) return Traverse_Result is
3460 if Nkind (N) = N_Attribute_Reference
3461 and then Attribute_Name (N) = Name_Result
3463 Result_Seen := True;
3466 -- Continue the traversal
3471 end Is_Function_Result;
3473 ------------------------
3474 -- Is_Trivial_Boolean --
3475 ------------------------
3477 function Is_Trivial_Boolean (N : Node_Id) return Boolean is
3480 Comes_From_Source (N)
3481 and then Is_Entity_Name (N)
3482 and then (Entity (N) = Standard_True
3483 or else Entity (N) = Standard_False);
3484 end Is_Trivial_Boolean;
3486 -------------------------
3487 -- Mentions_Post_State --
3488 -------------------------
3490 function Mentions_Post_State (N : Node_Id) return Boolean is
3491 Post_State_Seen : Boolean := False;
3493 function Is_Post_State (N : Node_Id) return Traverse_Result;
3494 -- Attempt to find a construct that denotes a post-state. If this
3495 -- is the case, set flag Post_State_Seen.
3501 function Is_Post_State (N : Node_Id) return Traverse_Result is
3505 if Nkind_In (N, N_Explicit_Dereference, N_Function_Call) then
3506 Post_State_Seen := True;
3509 elsif Nkind_In (N, N_Expanded_Name, N_Identifier) then
3512 if No (Ent) or else Ekind (Ent) in Assignable_Kind then
3513 Post_State_Seen := True;
3517 elsif Nkind (N) = N_Attribute_Reference then
3518 if Attribute_Name (N) = Name_Old then
3520 elsif Attribute_Name (N) = Name_Result then
3521 Post_State_Seen := True;
3529 procedure Find_Post_State is new Traverse_Proc (Is_Post_State);
3531 -- Start of processing for Mentions_Post_State
3534 Find_Post_State (N);
3535 return Post_State_Seen;
3536 end Mentions_Post_State;
3540 Expr : constant Node_Id :=
3541 Expression (First (Pragma_Argument_Associations (Prag)));
3542 Nam : constant Name_Id := Pragma_Name (Prag);
3545 -- Start of processing for Check_Result_And_Post_State
3548 if No (Error_Nod) then
3552 -- Examine all consequences
3554 if Nam = Name_Contract_Cases then
3555 CCase := First (Component_Associations (Expr));
3556 while Present (CCase) loop
3557 Check_Expression (Expression (CCase));
3562 -- Examine the expression of a postcondition
3565 pragma Assert (Nam = Name_Postcondition);
3566 Check_Expression (Expr);
3568 end Check_Result_And_Post_State;
3572 Items : constant Node_Id := Contract (Subp);
3573 Error_CCase : Node_Id;
3574 Error_Post : Node_Id;
3578 -- Start of processing for Analyze_Subprogram_Contract
3581 Error_CCase := Empty;
3582 Error_Post := Empty;
3584 if Present (Items) then
3586 -- Analyze pre- and postconditions
3588 Prag := Pre_Post_Conditions (Items);
3589 while Present (Prag) loop
3590 Analyze_Pre_Post_Condition_In_Decl_Part (Prag, Subp);
3592 -- Verify whether a postcondition mentions attribute 'Result and
3593 -- its expression introduces a post-state.
3595 if Warn_On_Suspicious_Contract
3596 and then Pragma_Name (Prag) = Name_Postcondition
3598 Check_Result_And_Post_State (Prag, Error_Post);
3601 Prag := Next_Pragma (Prag);
3604 -- Analyze contract-cases and test-cases
3606 Prag := Contract_Test_Cases (Items);
3607 while Present (Prag) loop
3608 Nam := Pragma_Name (Prag);
3610 if Nam = Name_Contract_Cases then
3611 Analyze_Contract_Cases_In_Decl_Part (Prag);
3613 -- Verify whether contract-cases mention attribute 'Result and
3614 -- its expression introduces a post-state. Perform the check
3615 -- only when the pragma is legal.
3617 if Warn_On_Suspicious_Contract
3618 and then not Error_Posted (Prag)
3620 Check_Result_And_Post_State (Prag, Error_CCase);
3624 pragma Assert (Nam = Name_Test_Case);
3625 Analyze_Test_Case_In_Decl_Part (Prag, Subp);
3628 Prag := Next_Pragma (Prag);
3631 -- Analyze classification pragmas
3633 Prag := Classifications (Contract (Subp));
3634 while Present (Prag) loop
3635 Nam := Pragma_Name (Prag);
3637 if Nam = Name_Depends then
3638 Analyze_Depends_In_Decl_Part (Prag);
3640 pragma Assert (Nam = Name_Global);
3641 Analyze_Global_In_Decl_Part (Prag);
3644 Prag := Next_Pragma (Prag);
3648 -- Emit an error when none of the postconditions or contract-cases
3649 -- mention attribute 'Result in the context of a function.
3651 if Warn_On_Suspicious_Contract
3652 and then Ekind_In (Subp, E_Function, E_Generic_Function)
3653 and then not Result_Seen
3655 if Present (Error_Post) and then Present (Error_CCase) then
3657 ("neither function postcondition nor contract cases mention "
3658 & "result?T?", Error_Post);
3660 elsif Present (Error_Post) then
3662 ("function postcondition does not mention result?T?",
3665 elsif Present (Error_CCase) then
3667 ("contract cases do not mention result?T?", Error_CCase);
3670 end Analyze_Subprogram_Contract;
3672 ------------------------------------
3673 -- Analyze_Subprogram_Declaration --
3674 ------------------------------------
3676 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
3677 Scop : constant Entity_Id := Current_Scope;
3678 Designator : Entity_Id;
3679 Is_Completion : Boolean;
3680 -- Indicates whether a null procedure declaration is a completion
3683 -- Null procedures are not allowed in SPARK
3685 if Nkind (Specification (N)) = N_Procedure_Specification
3686 and then Null_Present (Specification (N))
3688 Check_SPARK_Restriction ("null procedure is not allowed", N);
3690 if Is_Protected_Type (Current_Scope) then
3691 Error_Msg_N ("protected operation cannot be a null procedure", N);
3694 Analyze_Null_Procedure (N, Is_Completion);
3696 if Is_Completion then
3698 -- The null procedure acts as a body, nothing further is needed.
3704 Designator := Analyze_Subprogram_Specification (Specification (N));
3706 -- A reference may already have been generated for the unit name, in
3707 -- which case the following call is redundant. However it is needed for
3708 -- declarations that are the rewriting of an expression function.
3710 Generate_Definition (Designator);
3712 if Debug_Flag_C then
3713 Write_Str ("==> subprogram spec ");
3714 Write_Name (Chars (Designator));
3715 Write_Str (" from ");
3716 Write_Location (Sloc (N));
3721 Validate_RCI_Subprogram_Declaration (N);
3722 New_Overloaded_Entity (Designator);
3723 Check_Delayed_Subprogram (Designator);
3725 -- If the type of the first formal of the current subprogram is a
3726 -- non-generic tagged private type, mark the subprogram as being a
3727 -- private primitive. Ditto if this is a function with controlling
3728 -- result, and the return type is currently private. In both cases,
3729 -- the type of the controlling argument or result must be in the
3730 -- current scope for the operation to be primitive.
3732 if Has_Controlling_Result (Designator)
3733 and then Is_Private_Type (Etype (Designator))
3734 and then Scope (Etype (Designator)) = Current_Scope
3735 and then not Is_Generic_Actual_Type (Etype (Designator))
3737 Set_Is_Private_Primitive (Designator);
3739 elsif Present (First_Formal (Designator)) then
3741 Formal_Typ : constant Entity_Id :=
3742 Etype (First_Formal (Designator));
3744 Set_Is_Private_Primitive (Designator,
3745 Is_Tagged_Type (Formal_Typ)
3746 and then Scope (Formal_Typ) = Current_Scope
3747 and then Is_Private_Type (Formal_Typ)
3748 and then not Is_Generic_Actual_Type (Formal_Typ));
3752 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
3755 if Ada_Version >= Ada_2005
3756 and then Comes_From_Source (N)
3757 and then Is_Dispatching_Operation (Designator)
3764 if Has_Controlling_Result (Designator) then
3765 Etyp := Etype (Designator);
3768 E := First_Entity (Designator);
3770 and then Is_Formal (E)
3771 and then not Is_Controlling_Formal (E)
3779 if Is_Access_Type (Etyp) then
3780 Etyp := Directly_Designated_Type (Etyp);
3783 if Is_Interface (Etyp)
3784 and then not Is_Abstract_Subprogram (Designator)
3785 and then not (Ekind (Designator) = E_Procedure
3786 and then Null_Present (Specification (N)))
3788 Error_Msg_Name_1 := Chars (Defining_Entity (N));
3790 -- Specialize error message based on procedures vs. functions,
3791 -- since functions can't be null subprograms.
3793 if Ekind (Designator) = E_Procedure then
3795 ("interface procedure % must be abstract or null", N);
3797 Error_Msg_N ("interface function % must be abstract", N);
3803 -- What is the following code for, it used to be
3805 -- ??? Set_Suppress_Elaboration_Checks
3806 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
3808 -- The following seems equivalent, but a bit dubious
3810 if Elaboration_Checks_Suppressed (Designator) then
3811 Set_Kill_Elaboration_Checks (Designator);
3814 if Scop /= Standard_Standard and then not Is_Child_Unit (Designator) then
3815 Set_Categorization_From_Scope (Designator, Scop);
3818 -- For a compilation unit, check for library-unit pragmas
3820 Push_Scope (Designator);
3821 Set_Categorization_From_Pragmas (N);
3822 Validate_Categorization_Dependency (N, Designator);
3826 -- For a compilation unit, set body required. This flag will only be
3827 -- reset if a valid Import or Interface pragma is processed later on.
3829 if Nkind (Parent (N)) = N_Compilation_Unit then
3830 Set_Body_Required (Parent (N), True);
3832 if Ada_Version >= Ada_2005
3833 and then Nkind (Specification (N)) = N_Procedure_Specification
3834 and then Null_Present (Specification (N))
3837 ("null procedure cannot be declared at library level", N);
3841 Generate_Reference_To_Formals (Designator);
3842 Check_Eliminated (Designator);
3844 if Debug_Flag_C then
3846 Write_Str ("<== subprogram spec ");
3847 Write_Name (Chars (Designator));
3848 Write_Str (" from ");
3849 Write_Location (Sloc (N));
3853 if Is_Protected_Type (Current_Scope) then
3855 -- Indicate that this is a protected operation, because it may be
3856 -- used in subsequent declarations within the protected type.
3858 Set_Convention (Designator, Convention_Protected);
3861 List_Inherited_Pre_Post_Aspects (Designator);
3863 if Has_Aspects (N) then
3864 Analyze_Aspect_Specifications (N, Designator);
3866 end Analyze_Subprogram_Declaration;
3868 --------------------------------------
3869 -- Analyze_Subprogram_Specification --
3870 --------------------------------------
3872 -- Reminder: N here really is a subprogram specification (not a subprogram
3873 -- declaration). This procedure is called to analyze the specification in
3874 -- both subprogram bodies and subprogram declarations (specs).
3876 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
3877 Designator : constant Entity_Id := Defining_Entity (N);
3878 Formals : constant List_Id := Parameter_Specifications (N);
3880 -- Start of processing for Analyze_Subprogram_Specification
3883 -- User-defined operator is not allowed in SPARK, except as a renaming
3885 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
3886 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
3888 Check_SPARK_Restriction ("user-defined operator is not allowed", N);
3891 -- Proceed with analysis. Do not emit a cross-reference entry if the
3892 -- specification comes from an expression function, because it may be
3893 -- the completion of a previous declaration. It is is not, the cross-
3894 -- reference entry will be emitted for the new subprogram declaration.
3896 if Nkind (Parent (N)) /= N_Expression_Function then
3897 Generate_Definition (Designator);
3900 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
3902 if Nkind (N) = N_Function_Specification then
3903 Set_Ekind (Designator, E_Function);
3904 Set_Mechanism (Designator, Default_Mechanism);
3906 Set_Ekind (Designator, E_Procedure);
3907 Set_Etype (Designator, Standard_Void_Type);
3910 -- Introduce new scope for analysis of the formals and the return type
3912 Set_Scope (Designator, Current_Scope);
3914 if Present (Formals) then
3915 Push_Scope (Designator);
3916 Process_Formals (Formals, N);
3918 -- Check dimensions in N for formals with default expression
3920 Analyze_Dimension_Formals (N, Formals);
3922 -- Ada 2005 (AI-345): If this is an overriding operation of an
3923 -- inherited interface operation, and the controlling type is
3924 -- a synchronized type, replace the type with its corresponding
3925 -- record, to match the proper signature of an overriding operation.
3926 -- Same processing for an access parameter whose designated type is
3927 -- derived from a synchronized interface.
3929 if Ada_Version >= Ada_2005 then
3932 Formal_Typ : Entity_Id;
3933 Rec_Typ : Entity_Id;
3934 Desig_Typ : Entity_Id;
3937 Formal := First_Formal (Designator);
3938 while Present (Formal) loop
3939 Formal_Typ := Etype (Formal);
3941 if Is_Concurrent_Type (Formal_Typ)
3942 and then Present (Corresponding_Record_Type (Formal_Typ))
3944 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
3946 if Present (Interfaces (Rec_Typ)) then
3947 Set_Etype (Formal, Rec_Typ);
3950 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
3951 Desig_Typ := Designated_Type (Formal_Typ);
3953 if Is_Concurrent_Type (Desig_Typ)
3954 and then Present (Corresponding_Record_Type (Desig_Typ))
3956 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
3958 if Present (Interfaces (Rec_Typ)) then
3959 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
3964 Next_Formal (Formal);
3971 -- The subprogram scope is pushed and popped around the processing of
3972 -- the return type for consistency with call above to Process_Formals
3973 -- (which itself can call Analyze_Return_Type), and to ensure that any
3974 -- itype created for the return type will be associated with the proper
3977 elsif Nkind (N) = N_Function_Specification then
3978 Push_Scope (Designator);
3979 Analyze_Return_Type (N);
3985 if Nkind (N) = N_Function_Specification then
3987 -- Deal with operator symbol case
3989 if Nkind (Designator) = N_Defining_Operator_Symbol then
3990 Valid_Operator_Definition (Designator);
3993 May_Need_Actuals (Designator);
3995 -- Ada 2005 (AI-251): If the return type is abstract, verify that
3996 -- the subprogram is abstract also. This does not apply to renaming
3997 -- declarations, where abstractness is inherited, and to subprogram
3998 -- bodies generated for stream operations, which become renamings as
4001 -- In case of primitives associated with abstract interface types
4002 -- the check is applied later (see Analyze_Subprogram_Declaration).
4004 if not Nkind_In (Original_Node (Parent (N)),
4005 N_Subprogram_Renaming_Declaration,
4006 N_Abstract_Subprogram_Declaration,
4007 N_Formal_Abstract_Subprogram_Declaration)
4009 if Is_Abstract_Type (Etype (Designator))
4010 and then not Is_Interface (Etype (Designator))
4013 ("function that returns abstract type must be abstract", N);
4015 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
4016 -- access result whose designated type is abstract.
4018 elsif Nkind (Result_Definition (N)) = N_Access_Definition
4020 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
4021 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
4022 and then Ada_Version >= Ada_2012
4024 Error_Msg_N ("function whose access result designates "
4025 & "abstract type must be abstract", N);
4031 end Analyze_Subprogram_Specification;
4033 --------------------------
4034 -- Build_Body_To_Inline --
4035 --------------------------
4037 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
4038 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
4039 Original_Body : Node_Id;
4040 Body_To_Analyze : Node_Id;
4041 Max_Size : constant := 10;
4042 Stat_Count : Integer := 0;
4044 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
4045 -- Check for declarations that make inlining not worthwhile
4047 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
4048 -- Check for statements that make inlining not worthwhile: any tasking
4049 -- statement, nested at any level. Keep track of total number of
4050 -- elementary statements, as a measure of acceptable size.
4052 function Has_Pending_Instantiation return Boolean;
4053 -- If some enclosing body contains instantiations that appear before the
4054 -- corresponding generic body, the enclosing body has a freeze node so
4055 -- that it can be elaborated after the generic itself. This might
4056 -- conflict with subsequent inlinings, so that it is unsafe to try to
4057 -- inline in such a case.
4059 function Has_Single_Return return Boolean;
4060 -- In general we cannot inline functions that return unconstrained type.
4061 -- However, we can handle such functions if all return statements return
4062 -- a local variable that is the only declaration in the body of the
4063 -- function. In that case the call can be replaced by that local
4064 -- variable as is done for other inlined calls.
4066 procedure Remove_Pragmas;
4067 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
4068 -- parameter has no meaning when the body is inlined and the formals
4069 -- are rewritten. Remove it from body to inline. The analysis of the
4070 -- non-inlined body will handle the pragma properly.
4072 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
4073 -- If the body of the subprogram includes a call that returns an
4074 -- unconstrained type, the secondary stack is involved, and it
4075 -- is not worth inlining.
4077 ------------------------------
4078 -- Has_Excluded_Declaration --
4079 ------------------------------
4081 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
4084 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
4085 -- Nested subprograms make a given body ineligible for inlining, but
4086 -- we make an exception for instantiations of unchecked conversion.
4087 -- The body has not been analyzed yet, so check the name, and verify
4088 -- that the visible entity with that name is the predefined unit.
4090 -----------------------------
4091 -- Is_Unchecked_Conversion --
4092 -----------------------------
4094 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
4095 Id : constant Node_Id := Name (D);
4099 if Nkind (Id) = N_Identifier
4100 and then Chars (Id) = Name_Unchecked_Conversion
4102 Conv := Current_Entity (Id);
4104 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
4105 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
4107 Conv := Current_Entity (Selector_Name (Id));
4112 return Present (Conv)
4113 and then Is_Predefined_File_Name
4114 (Unit_File_Name (Get_Source_Unit (Conv)))
4115 and then Is_Intrinsic_Subprogram (Conv);
4116 end Is_Unchecked_Conversion;
4118 -- Start of processing for Has_Excluded_Declaration
4122 while Present (D) loop
4123 if (Nkind (D) = N_Function_Instantiation
4124 and then not Is_Unchecked_Conversion (D))
4125 or else Nkind_In (D, N_Protected_Type_Declaration,
4126 N_Package_Declaration,
4127 N_Package_Instantiation,
4129 N_Procedure_Instantiation,
4130 N_Task_Type_Declaration)
4133 ("cannot inline & (non-allowed declaration)?", D, Subp);
4141 end Has_Excluded_Declaration;
4143 ----------------------------
4144 -- Has_Excluded_Statement --
4145 ----------------------------
4147 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
4153 while Present (S) loop
4154 Stat_Count := Stat_Count + 1;
4156 if Nkind_In (S, N_Abort_Statement,
4157 N_Asynchronous_Select,
4158 N_Conditional_Entry_Call,
4159 N_Delay_Relative_Statement,
4160 N_Delay_Until_Statement,
4165 ("cannot inline & (non-allowed statement)?", S, Subp);
4168 elsif Nkind (S) = N_Block_Statement then
4169 if Present (Declarations (S))
4170 and then Has_Excluded_Declaration (Declarations (S))
4174 elsif Present (Handled_Statement_Sequence (S))
4177 (Exception_Handlers (Handled_Statement_Sequence (S)))
4179 Has_Excluded_Statement
4180 (Statements (Handled_Statement_Sequence (S))))
4185 elsif Nkind (S) = N_Case_Statement then
4186 E := First (Alternatives (S));
4187 while Present (E) loop
4188 if Has_Excluded_Statement (Statements (E)) then
4195 elsif Nkind (S) = N_If_Statement then
4196 if Has_Excluded_Statement (Then_Statements (S)) then
4200 if Present (Elsif_Parts (S)) then
4201 E := First (Elsif_Parts (S));
4202 while Present (E) loop
4203 if Has_Excluded_Statement (Then_Statements (E)) then
4211 if Present (Else_Statements (S))
4212 and then Has_Excluded_Statement (Else_Statements (S))
4217 elsif Nkind (S) = N_Loop_Statement
4218 and then Has_Excluded_Statement (Statements (S))
4222 elsif Nkind (S) = N_Extended_Return_Statement then
4223 if Has_Excluded_Statement
4224 (Statements (Handled_Statement_Sequence (S)))
4226 (Exception_Handlers (Handled_Statement_Sequence (S)))
4236 end Has_Excluded_Statement;
4238 -------------------------------
4239 -- Has_Pending_Instantiation --
4240 -------------------------------
4242 function Has_Pending_Instantiation return Boolean is
4247 while Present (S) loop
4248 if Is_Compilation_Unit (S)
4249 or else Is_Child_Unit (S)
4253 elsif Ekind (S) = E_Package
4254 and then Has_Forward_Instantiation (S)
4263 end Has_Pending_Instantiation;
4265 ------------------------
4266 -- Has_Single_Return --
4267 ------------------------
4269 function Has_Single_Return return Boolean is
4270 Return_Statement : Node_Id := Empty;
4272 function Check_Return (N : Node_Id) return Traverse_Result;
4278 function Check_Return (N : Node_Id) return Traverse_Result is
4280 if Nkind (N) = N_Simple_Return_Statement then
4281 if Present (Expression (N))
4282 and then Is_Entity_Name (Expression (N))
4284 if No (Return_Statement) then
4285 Return_Statement := N;
4288 elsif Chars (Expression (N)) =
4289 Chars (Expression (Return_Statement))
4297 -- A return statement within an extended return is a noop
4300 elsif No (Expression (N))
4301 and then Nkind (Parent (Parent (N))) =
4302 N_Extended_Return_Statement
4307 -- Expression has wrong form
4312 -- We can only inline a build-in-place function if
4313 -- it has a single extended return.
4315 elsif Nkind (N) = N_Extended_Return_Statement then
4316 if No (Return_Statement) then
4317 Return_Statement := N;
4329 function Check_All_Returns is new Traverse_Func (Check_Return);
4331 -- Start of processing for Has_Single_Return
4334 if Check_All_Returns (N) /= OK then
4337 elsif Nkind (Return_Statement) = N_Extended_Return_Statement then
4341 return Present (Declarations (N))
4342 and then Present (First (Declarations (N)))
4343 and then Chars (Expression (Return_Statement)) =
4344 Chars (Defining_Identifier (First (Declarations (N))));
4346 end Has_Single_Return;
4348 --------------------
4349 -- Remove_Pragmas --
4350 --------------------
4352 procedure Remove_Pragmas is
4357 Decl := First (Declarations (Body_To_Analyze));
4358 while Present (Decl) loop
4361 if Nkind (Decl) = N_Pragma
4362 and then Nam_In (Pragma_Name (Decl), Name_Unreferenced,
4372 --------------------------
4373 -- Uses_Secondary_Stack --
4374 --------------------------
4376 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
4377 function Check_Call (N : Node_Id) return Traverse_Result;
4378 -- Look for function calls that return an unconstrained type
4384 function Check_Call (N : Node_Id) return Traverse_Result is
4386 if Nkind (N) = N_Function_Call
4387 and then Is_Entity_Name (Name (N))
4388 and then Is_Composite_Type (Etype (Entity (Name (N))))
4389 and then not Is_Constrained (Etype (Entity (Name (N))))
4392 ("cannot inline & (call returns unconstrained type)?",
4400 function Check_Calls is new Traverse_Func (Check_Call);
4403 return Check_Calls (Bod) = Abandon;
4404 end Uses_Secondary_Stack;
4406 -- Start of processing for Build_Body_To_Inline
4409 -- Return immediately if done already
4411 if Nkind (Decl) = N_Subprogram_Declaration
4412 and then Present (Body_To_Inline (Decl))
4416 -- Functions that return unconstrained composite types require
4417 -- secondary stack handling, and cannot currently be inlined, unless
4418 -- all return statements return a local variable that is the first
4419 -- local declaration in the body.
4421 elsif Ekind (Subp) = E_Function
4422 and then not Is_Scalar_Type (Etype (Subp))
4423 and then not Is_Access_Type (Etype (Subp))
4424 and then not Is_Constrained (Etype (Subp))
4426 if not Has_Single_Return then
4428 ("cannot inline & (unconstrained return type)?", N, Subp);
4432 -- Ditto for functions that return controlled types, where controlled
4433 -- actions interfere in complex ways with inlining.
4435 elsif Ekind (Subp) = E_Function
4436 and then Needs_Finalization (Etype (Subp))
4439 ("cannot inline & (controlled return type)?", N, Subp);
4443 if Present (Declarations (N))
4444 and then Has_Excluded_Declaration (Declarations (N))
4449 if Present (Handled_Statement_Sequence (N)) then
4450 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
4452 ("cannot inline& (exception handler)?",
4453 First (Exception_Handlers (Handled_Statement_Sequence (N))),
4457 Has_Excluded_Statement
4458 (Statements (Handled_Statement_Sequence (N)))
4464 -- We do not inline a subprogram that is too large, unless it is
4465 -- marked Inline_Always. This pragma does not suppress the other
4466 -- checks on inlining (forbidden declarations, handlers, etc).
4468 if Stat_Count > Max_Size
4469 and then not Has_Pragma_Inline_Always (Subp)
4471 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
4475 if Has_Pending_Instantiation then
4477 ("cannot inline& (forward instance within enclosing body)?",
4482 -- Within an instance, the body to inline must be treated as a nested
4483 -- generic, so that the proper global references are preserved.
4485 -- Note that we do not do this at the library level, because it is not
4486 -- needed, and furthermore this causes trouble if front end inlining
4487 -- is activated (-gnatN).
4489 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
4490 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
4491 Original_Body := Copy_Generic_Node (N, Empty, True);
4493 Original_Body := Copy_Separate_Tree (N);
4496 -- We need to capture references to the formals in order to substitute
4497 -- the actuals at the point of inlining, i.e. instantiation. To treat
4498 -- the formals as globals to the body to inline, we nest it within
4499 -- a dummy parameterless subprogram, declared within the real one.
4500 -- To avoid generating an internal name (which is never public, and
4501 -- which affects serial numbers of other generated names), we use
4502 -- an internal symbol that cannot conflict with user declarations.
4504 Set_Parameter_Specifications (Specification (Original_Body), No_List);
4505 Set_Defining_Unit_Name
4506 (Specification (Original_Body),
4507 Make_Defining_Identifier (Sloc (N), Name_uParent));
4508 Set_Corresponding_Spec (Original_Body, Empty);
4510 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
4512 -- Set return type of function, which is also global and does not need
4515 if Ekind (Subp) = E_Function then
4516 Set_Result_Definition (Specification (Body_To_Analyze),
4517 New_Occurrence_Of (Etype (Subp), Sloc (N)));
4520 if No (Declarations (N)) then
4521 Set_Declarations (N, New_List (Body_To_Analyze));
4523 Append (Body_To_Analyze, Declarations (N));
4526 Expander_Mode_Save_And_Set (False);
4529 Analyze (Body_To_Analyze);
4530 Push_Scope (Defining_Entity (Body_To_Analyze));
4531 Save_Global_References (Original_Body);
4533 Remove (Body_To_Analyze);
4535 Expander_Mode_Restore;
4537 -- Restore environment if previously saved
4539 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
4543 -- If secondary stk used there is no point in inlining. We have
4544 -- already issued the warning in this case, so nothing to do.
4546 if Uses_Secondary_Stack (Body_To_Analyze) then
4550 Set_Body_To_Inline (Decl, Original_Body);
4551 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
4552 Set_Is_Inlined (Subp);
4553 end Build_Body_To_Inline;
4559 procedure Cannot_Inline
4563 Is_Serious : Boolean := False)
4566 pragma Assert (Msg (Msg'Last) = '?');
4570 if not Debug_Flag_Dot_K then
4572 -- Do not emit warning if this is a predefined unit which is not
4573 -- the main unit. With validity checks enabled, some predefined
4574 -- subprograms may contain nested subprograms and become ineligible
4577 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
4578 and then not In_Extended_Main_Source_Unit (Subp)
4582 elsif Has_Pragma_Inline_Always (Subp) then
4584 -- Remove last character (question mark) to make this into an
4585 -- error, because the Inline_Always pragma cannot be obeyed.
4587 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
4589 elsif Ineffective_Inline_Warnings then
4590 Error_Msg_NE (Msg & "p?", N, Subp);
4597 elsif Is_Serious then
4599 -- Remove last character (question mark) to make this into an error.
4601 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
4603 elsif Optimization_Level = 0 then
4605 -- Do not emit warning if this is a predefined unit which is not
4606 -- the main unit. This behavior is currently provided for backward
4607 -- compatibility but it will be removed when we enforce the
4608 -- strictness of the new rules.
4610 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
4611 and then not In_Extended_Main_Source_Unit (Subp)
4615 elsif Has_Pragma_Inline_Always (Subp) then
4617 -- Emit a warning if this is a call to a runtime subprogram
4618 -- which is located inside a generic. Previously this call
4619 -- was silently skipped!
4621 if Is_Generic_Instance (Subp) then
4623 Gen_P : constant Entity_Id := Generic_Parent (Parent (Subp));
4625 if Is_Predefined_File_Name
4626 (Unit_File_Name (Get_Source_Unit (Gen_P)))
4628 Set_Is_Inlined (Subp, False);
4629 Error_Msg_NE (Msg & "p?", N, Subp);
4635 -- Remove last character (question mark) to make this into an
4636 -- error, because the Inline_Always pragma cannot be obeyed.
4638 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
4640 else pragma Assert (Front_End_Inlining);
4641 Set_Is_Inlined (Subp, False);
4643 -- When inlining cannot take place we must issue an error.
4644 -- For backward compatibility we still report a warning.
4646 if Ineffective_Inline_Warnings then
4647 Error_Msg_NE (Msg & "p?", N, Subp);
4651 -- Compiling with optimizations enabled it is too early to report
4652 -- problems since the backend may still perform inlining. In order
4653 -- to report unhandled inlinings the program must be compiled with
4654 -- -Winline and the error is reported by the backend.
4661 ------------------------------------
4662 -- Check_And_Build_Body_To_Inline --
4663 ------------------------------------
4665 procedure Check_And_Build_Body_To_Inline
4667 Spec_Id : Entity_Id;
4668 Body_Id : Entity_Id)
4670 procedure Build_Body_To_Inline (N : Node_Id; Spec_Id : Entity_Id);
4671 -- Use generic machinery to build an unexpanded body for the subprogram.
4672 -- This body is subsequently used for inline expansions at call sites.
4674 function Can_Split_Unconstrained_Function (N : Node_Id) return Boolean;
4675 -- Return true if we generate code for the function body N, the function
4676 -- body N has no local declarations and its unique statement is a single
4677 -- extended return statement with a handled statements sequence.
4679 function Check_Body_To_Inline
4681 Subp : Entity_Id) return Boolean;
4682 -- N is the N_Subprogram_Body of Subp. Return true if Subp can be
4683 -- inlined by the frontend. These are the rules:
4684 -- * At -O0 use fe inlining when inline_always is specified except if
4685 -- the function returns a controlled type.
4686 -- * At other optimization levels use the fe inlining for both inline
4687 -- and inline_always in the following cases:
4688 -- - function returning a known at compile time constant
4689 -- - function returning a call to an intrinsic function
4690 -- - function returning an unconstrained type (see Can_Split
4691 -- Unconstrained_Function).
4692 -- - function returning a call to a frontend-inlined function
4693 -- Use the back-end mechanism otherwise
4695 -- In addition, in the following cases the function cannot be inlined by
4697 -- - functions that uses the secondary stack
4698 -- - functions that have declarations of:
4699 -- - Concurrent types
4703 -- - functions that have some of the following statements:
4705 -- - asynchronous-select
4706 -- - conditional-entry-call
4709 -- - selective-accept
4710 -- - timed-entry-call
4711 -- - functions that have exception handlers
4712 -- - functions that have some enclosing body containing instantiations
4713 -- that appear before the corresponding generic body.
4715 procedure Generate_Body_To_Inline
4717 Body_To_Inline : out Node_Id);
4718 -- Generate a parameterless duplicate of subprogram body N. Occurrences
4719 -- of pragmas referencing the formals are removed since they have no
4720 -- meaning when the body is inlined and the formals are rewritten (the
4721 -- analysis of the non-inlined body will handle these pragmas properly).
4722 -- A new internal name is associated with Body_To_Inline.
4724 procedure Split_Unconstrained_Function
4726 Spec_Id : Entity_Id);
4727 -- N is an inlined function body that returns an unconstrained type and
4728 -- has a single extended return statement. Split N in two subprograms:
4729 -- a procedure P' and a function F'. The formals of P' duplicate the
4730 -- formals of N plus an extra formal which is used return a value;
4731 -- its body is composed by the declarations and list of statements
4732 -- of the extended return statement of N.
4734 --------------------------
4735 -- Build_Body_To_Inline --
4736 --------------------------
4738 procedure Build_Body_To_Inline (N : Node_Id; Spec_Id : Entity_Id) is
4739 Decl : constant Node_Id := Unit_Declaration_Node (Spec_Id);
4740 Original_Body : Node_Id;
4741 Body_To_Analyze : Node_Id;
4744 pragma Assert (Current_Scope = Spec_Id);
4746 -- Within an instance, the body to inline must be treated as a nested
4747 -- generic, so that the proper global references are preserved. We
4748 -- do not do this at the library level, because it is not needed, and
4749 -- furthermore this causes trouble if front end inlining is activated
4753 and then Scope (Current_Scope) /= Standard_Standard
4755 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
4758 -- We need to capture references to the formals in order
4759 -- to substitute the actuals at the point of inlining, i.e.
4760 -- instantiation. To treat the formals as globals to the body to
4761 -- inline, we nest it within a dummy parameterless subprogram,
4762 -- declared within the real one.
4764 Generate_Body_To_Inline (N, Original_Body);
4765 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
4767 -- Set return type of function, which is also global and does not
4768 -- need to be resolved.
4770 if Ekind (Spec_Id) = E_Function then
4771 Set_Result_Definition (Specification (Body_To_Analyze),
4772 New_Occurrence_Of (Etype (Spec_Id), Sloc (N)));
4775 if No (Declarations (N)) then
4776 Set_Declarations (N, New_List (Body_To_Analyze));
4778 Append_To (Declarations (N), Body_To_Analyze);
4781 Preanalyze (Body_To_Analyze);
4783 Push_Scope (Defining_Entity (Body_To_Analyze));
4784 Save_Global_References (Original_Body);
4786 Remove (Body_To_Analyze);
4788 -- Restore environment if previously saved
4791 and then Scope (Current_Scope) /= Standard_Standard
4796 pragma Assert (No (Body_To_Inline (Decl)));
4797 Set_Body_To_Inline (Decl, Original_Body);
4798 Set_Ekind (Defining_Entity (Original_Body), Ekind (Spec_Id));
4799 end Build_Body_To_Inline;
4801 --------------------------
4802 -- Check_Body_To_Inline --
4803 --------------------------
4805 function Check_Body_To_Inline
4807 Subp : Entity_Id) return Boolean
4809 Max_Size : constant := 10;
4810 Stat_Count : Integer := 0;
4812 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
4813 -- Check for declarations that make inlining not worthwhile
4815 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
4816 -- Check for statements that make inlining not worthwhile: any
4817 -- tasking statement, nested at any level. Keep track of total
4818 -- number of elementary statements, as a measure of acceptable size.
4820 function Has_Pending_Instantiation return Boolean;
4821 -- Return True if some enclosing body contains instantiations that
4822 -- appear before the corresponding generic body.
4824 function Returns_Compile_Time_Constant (N : Node_Id) return Boolean;
4825 -- Return True if all the return statements of the function body N
4826 -- are simple return statements and return a compile time constant
4828 function Returns_Intrinsic_Function_Call (N : Node_Id) return Boolean;
4829 -- Return True if all the return statements of the function body N
4830 -- are simple return statements and return an intrinsic function call
4832 function Uses_Secondary_Stack (N : Node_Id) return Boolean;
4833 -- If the body of the subprogram includes a call that returns an
4834 -- unconstrained type, the secondary stack is involved, and it
4835 -- is not worth inlining.
4837 ------------------------------
4838 -- Has_Excluded_Declaration --
4839 ------------------------------
4841 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
4844 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
4845 -- Nested subprograms make a given body ineligible for inlining,
4846 -- but we make an exception for instantiations of unchecked
4847 -- conversion. The body has not been analyzed yet, so check the
4848 -- name, and verify that the visible entity with that name is the
4851 -----------------------------
4852 -- Is_Unchecked_Conversion --
4853 -----------------------------
4855 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
4856 Id : constant Node_Id := Name (D);
4860 if Nkind (Id) = N_Identifier
4861 and then Chars (Id) = Name_Unchecked_Conversion
4863 Conv := Current_Entity (Id);
4865 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
4867 Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
4869 Conv := Current_Entity (Selector_Name (Id));
4874 return Present (Conv)
4875 and then Is_Predefined_File_Name
4876 (Unit_File_Name (Get_Source_Unit (Conv)))
4877 and then Is_Intrinsic_Subprogram (Conv);
4878 end Is_Unchecked_Conversion;
4880 -- Start of processing for Has_Excluded_Declaration
4884 while Present (D) loop
4885 if (Nkind (D) = N_Function_Instantiation
4886 and then not Is_Unchecked_Conversion (D))
4887 or else Nkind_In (D, N_Protected_Type_Declaration,
4888 N_Package_Declaration,
4889 N_Package_Instantiation,
4891 N_Procedure_Instantiation,
4892 N_Task_Type_Declaration)
4895 ("cannot inline & (non-allowed declaration)?", D, Subp);
4904 end Has_Excluded_Declaration;
4906 ----------------------------
4907 -- Has_Excluded_Statement --
4908 ----------------------------
4910 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
4916 while Present (S) loop
4917 Stat_Count := Stat_Count + 1;
4919 if Nkind_In (S, N_Abort_Statement,
4920 N_Asynchronous_Select,
4921 N_Conditional_Entry_Call,
4922 N_Delay_Relative_Statement,
4923 N_Delay_Until_Statement,
4928 ("cannot inline & (non-allowed statement)?", S, Subp);
4931 elsif Nkind (S) = N_Block_Statement then
4932 if Present (Declarations (S))
4933 and then Has_Excluded_Declaration (Declarations (S))
4937 elsif Present (Handled_Statement_Sequence (S)) then
4939 (Exception_Handlers (Handled_Statement_Sequence (S)))
4942 ("cannot inline& (exception handler)?",
4943 First (Exception_Handlers
4944 (Handled_Statement_Sequence (S))),
4948 elsif Has_Excluded_Statement
4949 (Statements (Handled_Statement_Sequence (S)))
4955 elsif Nkind (S) = N_Case_Statement then
4956 E := First (Alternatives (S));
4957 while Present (E) loop
4958 if Has_Excluded_Statement (Statements (E)) then
4965 elsif Nkind (S) = N_If_Statement then
4966 if Has_Excluded_Statement (Then_Statements (S)) then
4970 if Present (Elsif_Parts (S)) then
4971 E := First (Elsif_Parts (S));
4972 while Present (E) loop
4973 if Has_Excluded_Statement (Then_Statements (E)) then
4980 if Present (Else_Statements (S))
4981 and then Has_Excluded_Statement (Else_Statements (S))
4986 elsif Nkind (S) = N_Loop_Statement
4987 and then Has_Excluded_Statement (Statements (S))
4991 elsif Nkind (S) = N_Extended_Return_Statement then
4992 if Present (Handled_Statement_Sequence (S))
4994 Has_Excluded_Statement
4995 (Statements (Handled_Statement_Sequence (S)))
4999 elsif Present (Handled_Statement_Sequence (S))
5001 Present (Exception_Handlers
5002 (Handled_Statement_Sequence (S)))
5005 ("cannot inline& (exception handler)?",
5006 First (Exception_Handlers
5007 (Handled_Statement_Sequence (S))),
5017 end Has_Excluded_Statement;
5019 -------------------------------
5020 -- Has_Pending_Instantiation --
5021 -------------------------------
5023 function Has_Pending_Instantiation return Boolean is
5028 while Present (S) loop
5029 if Is_Compilation_Unit (S)
5030 or else Is_Child_Unit (S)
5034 elsif Ekind (S) = E_Package
5035 and then Has_Forward_Instantiation (S)
5044 end Has_Pending_Instantiation;
5046 ------------------------------------
5047 -- Returns_Compile_Time_Constant --
5048 ------------------------------------
5050 function Returns_Compile_Time_Constant (N : Node_Id) return Boolean is
5052 function Check_Return (N : Node_Id) return Traverse_Result;
5058 function Check_Return (N : Node_Id) return Traverse_Result is
5060 if Nkind (N) = N_Extended_Return_Statement then
5063 elsif Nkind (N) = N_Simple_Return_Statement then
5064 if Present (Expression (N)) then
5066 Orig_Expr : constant Node_Id :=
5067 Original_Node (Expression (N));
5070 if Nkind_In (Orig_Expr, N_Integer_Literal,
5072 N_Character_Literal)
5076 elsif Is_Entity_Name (Orig_Expr)
5077 and then Ekind (Entity (Orig_Expr)) = E_Constant
5078 and then Is_Static_Expression (Orig_Expr)
5086 -- Expression has wrong form
5092 -- Continue analyzing statements
5099 function Check_All_Returns is new Traverse_Func (Check_Return);
5101 -- Start of processing for Returns_Compile_Time_Constant
5104 return Check_All_Returns (N) = OK;
5105 end Returns_Compile_Time_Constant;
5107 --------------------------------------
5108 -- Returns_Intrinsic_Function_Call --
5109 --------------------------------------
5111 function Returns_Intrinsic_Function_Call
5112 (N : Node_Id) return Boolean
5114 function Check_Return (N : Node_Id) return Traverse_Result;
5120 function Check_Return (N : Node_Id) return Traverse_Result is
5122 if Nkind (N) = N_Extended_Return_Statement then
5125 elsif Nkind (N) = N_Simple_Return_Statement then
5126 if Present (Expression (N)) then
5128 Orig_Expr : constant Node_Id :=
5129 Original_Node (Expression (N));
5132 if Nkind (Orig_Expr) in N_Op
5133 and then Is_Intrinsic_Subprogram (Entity (Orig_Expr))
5137 elsif Nkind (Orig_Expr) in N_Has_Entity
5138 and then Present (Entity (Orig_Expr))
5139 and then Ekind (Entity (Orig_Expr)) = E_Function
5140 and then Is_Inlined (Entity (Orig_Expr))
5144 elsif Nkind (Orig_Expr) in N_Has_Entity
5145 and then Present (Entity (Orig_Expr))
5146 and then Is_Intrinsic_Subprogram (Entity (Orig_Expr))
5155 -- Expression has wrong form
5161 -- Continue analyzing statements
5168 function Check_All_Returns is new Traverse_Func (Check_Return);
5170 -- Start of processing for Returns_Intrinsic_Function_Call
5173 return Check_All_Returns (N) = OK;
5174 end Returns_Intrinsic_Function_Call;
5176 --------------------------
5177 -- Uses_Secondary_Stack --
5178 --------------------------
5180 function Uses_Secondary_Stack (N : Node_Id) return Boolean is
5182 function Check_Call (N : Node_Id) return Traverse_Result;
5183 -- Look for function calls that return an unconstrained type
5189 function Check_Call (N : Node_Id) return Traverse_Result is
5191 if Nkind (N) = N_Function_Call
5192 and then Is_Entity_Name (Name (N))
5193 and then Is_Composite_Type (Etype (Entity (Name (N))))
5194 and then not Is_Constrained (Etype (Entity (Name (N))))
5197 ("cannot inline & (call returns unconstrained type)?",
5206 function Check_Calls is new Traverse_Func (Check_Call);
5208 -- Start of processing for Uses_Secondary_Stack
5211 return Check_Calls (N) = Abandon;
5212 end Uses_Secondary_Stack;
5216 Decl : constant Node_Id := Unit_Declaration_Node (Spec_Id);
5217 May_Inline : constant Boolean :=
5218 Has_Pragma_Inline_Always (Spec_Id)
5219 or else (Has_Pragma_Inline (Spec_Id)
5220 and then ((Optimization_Level > 0
5221 and then Ekind (Spec_Id)
5223 or else Front_End_Inlining));
5224 Body_To_Analyze : Node_Id;
5226 -- Start of processing for Check_Body_To_Inline
5229 -- No action needed in stubs since the attribute Body_To_Inline
5232 if Nkind (Decl) = N_Subprogram_Body_Stub then
5235 -- Cannot build the body to inline if the attribute is already set.
5236 -- This attribute may have been set if this is a subprogram renaming
5237 -- declarations (see Freeze.Build_Renamed_Body).
5239 elsif Present (Body_To_Inline (Decl)) then
5242 -- No action needed if the subprogram does not fulfill the minimum
5243 -- conditions to be inlined by the frontend
5245 elsif not May_Inline then
5249 -- Check excluded declarations
5251 if Present (Declarations (N))
5252 and then Has_Excluded_Declaration (Declarations (N))
5257 -- Check excluded statements
5259 if Present (Handled_Statement_Sequence (N)) then
5261 (Exception_Handlers (Handled_Statement_Sequence (N)))
5264 ("cannot inline& (exception handler)?",
5266 (Exception_Handlers (Handled_Statement_Sequence (N))),
5271 elsif Has_Excluded_Statement
5272 (Statements (Handled_Statement_Sequence (N)))
5278 -- For backward compatibility, compiling under -gnatN we do not
5279 -- inline a subprogram that is too large, unless it is marked
5280 -- Inline_Always. This pragma does not suppress the other checks
5281 -- on inlining (forbidden declarations, handlers, etc).
5283 if Front_End_Inlining
5284 and then not Has_Pragma_Inline_Always (Subp)
5285 and then Stat_Count > Max_Size
5287 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
5291 -- If some enclosing body contains instantiations that appear before
5292 -- the corresponding generic body, the enclosing body has a freeze
5293 -- node so that it can be elaborated after the generic itself. This
5294 -- might conflict with subsequent inlinings, so that it is unsafe to
5295 -- try to inline in such a case.
5297 if Has_Pending_Instantiation then
5299 ("cannot inline& (forward instance within enclosing body)?",
5305 -- Generate and preanalyze the body to inline (needed to perform
5306 -- the rest of the checks)
5308 Generate_Body_To_Inline (N, Body_To_Analyze);
5310 if Ekind (Subp) = E_Function then
5311 Set_Result_Definition (Specification (Body_To_Analyze),
5312 New_Occurrence_Of (Etype (Subp), Sloc (N)));
5315 -- Nest the body to analyze within the real one
5317 if No (Declarations (N)) then
5318 Set_Declarations (N, New_List (Body_To_Analyze));
5320 Append_To (Declarations (N), Body_To_Analyze);
5323 Preanalyze (Body_To_Analyze);
5324 Remove (Body_To_Analyze);
5326 -- Keep separate checks needed when compiling without optimizations
5328 if Optimization_Level = 0
5330 -- AAMP and VM targets have no support for inlining in the backend
5331 -- and hence we use frontend inlining at all optimization levels.
5333 or else AAMP_On_Target
5334 or else VM_Target /= No_VM
5336 -- Cannot inline functions whose body has a call that returns an
5337 -- unconstrained type since the secondary stack is involved, and
5338 -- it is not worth inlining.
5340 if Uses_Secondary_Stack (Body_To_Analyze) then
5343 -- Cannot inline functions that return controlled types since
5344 -- controlled actions interfere in complex ways with inlining.
5346 elsif Ekind (Subp) = E_Function
5347 and then Needs_Finalization (Etype (Subp))
5350 ("cannot inline & (controlled return type)?", N, Subp);
5353 elsif Returns_Unconstrained_Type (Subp) then
5355 ("cannot inline & (unconstrained return type)?", N, Subp);
5359 -- Compiling with optimizations enabled
5362 -- Procedures are never frontend inlined in this case!
5364 if Ekind (Subp) /= E_Function then
5367 -- Functions returning unconstrained types are tested
5368 -- separately (see Can_Split_Unconstrained_Function).
5370 elsif Returns_Unconstrained_Type (Subp) then
5373 -- Check supported cases
5375 elsif not Returns_Compile_Time_Constant (Body_To_Analyze)
5376 and then Convention (Subp) /= Convention_Intrinsic
5377 and then not Returns_Intrinsic_Function_Call (Body_To_Analyze)
5384 end Check_Body_To_Inline;
5386 --------------------------------------
5387 -- Can_Split_Unconstrained_Function --
5388 --------------------------------------
5390 function Can_Split_Unconstrained_Function (N : Node_Id) return Boolean
5392 Ret_Node : constant Node_Id :=
5393 First (Statements (Handled_Statement_Sequence (N)));
5397 -- No user defined declarations allowed in the function except inside
5398 -- the unique return statement; implicit labels are the only allowed
5401 if not Is_Empty_List (Declarations (N)) then
5402 D := First (Declarations (N));
5403 while Present (D) loop
5404 if Nkind (D) /= N_Implicit_Label_Declaration then
5412 -- We only split the inlined function when we are generating the code
5413 -- of its body; otherwise we leave duplicated split subprograms in
5414 -- the tree which (if referenced) generate wrong references at link
5417 return In_Extended_Main_Code_Unit (N)
5418 and then Present (Ret_Node)
5419 and then Nkind (Ret_Node) = N_Extended_Return_Statement
5420 and then No (Next (Ret_Node))
5421 and then Present (Handled_Statement_Sequence (Ret_Node));
5422 end Can_Split_Unconstrained_Function;
5424 -----------------------------
5425 -- Generate_Body_To_Inline --
5426 -----------------------------
5428 procedure Generate_Body_To_Inline
5430 Body_To_Inline : out Node_Id)
5432 procedure Remove_Pragmas (N : Node_Id);
5433 -- Remove occurrences of pragmas that may reference the formals of
5434 -- N. The analysis of the non-inlined body will handle these pragmas
5437 --------------------
5438 -- Remove_Pragmas --
5439 --------------------
5441 procedure Remove_Pragmas (N : Node_Id) is
5446 Decl := First (Declarations (N));
5447 while Present (Decl) loop
5450 if Nkind (Decl) = N_Pragma
5451 and then Nam_In (Pragma_Name (Decl), Name_Unreferenced,
5461 -- Start of processing for Generate_Body_To_Inline
5464 -- Within an instance, the body to inline must be treated as a nested
5465 -- generic, so that the proper global references are preserved.
5467 -- Note that we do not do this at the library level, because it
5468 -- is not needed, and furthermore this causes trouble if front
5469 -- end inlining is activated (-gnatN).
5472 and then Scope (Current_Scope) /= Standard_Standard
5474 Body_To_Inline := Copy_Generic_Node (N, Empty, True);
5476 Body_To_Inline := Copy_Separate_Tree (N);
5479 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
5480 -- parameter has no meaning when the body is inlined and the formals
5481 -- are rewritten. Remove it from body to inline. The analysis of the
5482 -- non-inlined body will handle the pragma properly.
5484 Remove_Pragmas (Body_To_Inline);
5486 -- We need to capture references to the formals in order
5487 -- to substitute the actuals at the point of inlining, i.e.
5488 -- instantiation. To treat the formals as globals to the body to
5489 -- inline, we nest it within a dummy parameterless subprogram,
5490 -- declared within the real one.
5492 Set_Parameter_Specifications
5493 (Specification (Body_To_Inline), No_List);
5495 -- A new internal name is associated with Body_To_Inline to avoid
5496 -- conflicts when the non-inlined body N is analyzed.
5498 Set_Defining_Unit_Name (Specification (Body_To_Inline),
5499 Make_Defining_Identifier (Sloc (N), New_Internal_Name ('P')));
5500 Set_Corresponding_Spec (Body_To_Inline, Empty);
5501 end Generate_Body_To_Inline;
5503 ----------------------------------
5504 -- Split_Unconstrained_Function --
5505 ----------------------------------
5507 procedure Split_Unconstrained_Function
5509 Spec_Id : Entity_Id)
5511 Loc : constant Source_Ptr := Sloc (N);
5512 Ret_Node : constant Node_Id :=
5513 First (Statements (Handled_Statement_Sequence (N)));
5514 Ret_Obj : constant Node_Id :=
5515 First (Return_Object_Declarations (Ret_Node));
5517 procedure Build_Procedure
5518 (Proc_Id : out Entity_Id;
5519 Decl_List : out List_Id);
5520 -- Build a procedure containing the statements found in the extended
5521 -- return statement of the unconstrained function body N.
5523 procedure Build_Procedure
5524 (Proc_Id : out Entity_Id;
5525 Decl_List : out List_Id)
5528 Formal_List : constant List_Id := New_List;
5529 Proc_Spec : Node_Id;
5530 Proc_Body : Node_Id;
5531 Subp_Name : constant Name_Id := New_Internal_Name ('F');
5532 Body_Decl_List : List_Id := No_List;
5533 Param_Type : Node_Id;
5536 if Nkind (Object_Definition (Ret_Obj)) = N_Identifier then
5537 Param_Type := New_Copy (Object_Definition (Ret_Obj));
5540 New_Copy (Subtype_Mark (Object_Definition (Ret_Obj)));
5543 Append_To (Formal_List,
5544 Make_Parameter_Specification (Loc,
5545 Defining_Identifier =>
5546 Make_Defining_Identifier (Loc,
5547 Chars => Chars (Defining_Identifier (Ret_Obj))),
5548 In_Present => False,
5549 Out_Present => True,
5550 Null_Exclusion_Present => False,
5551 Parameter_Type => Param_Type));
5553 Formal := First_Formal (Spec_Id);
5554 while Present (Formal) loop
5555 Append_To (Formal_List,
5556 Make_Parameter_Specification (Loc,
5557 Defining_Identifier =>
5558 Make_Defining_Identifier (Sloc (Formal),
5559 Chars => Chars (Formal)),
5560 In_Present => In_Present (Parent (Formal)),
5561 Out_Present => Out_Present (Parent (Formal)),
5562 Null_Exclusion_Present =>
5563 Null_Exclusion_Present (Parent (Formal)),
5565 New_Reference_To (Etype (Formal), Loc),
5567 Copy_Separate_Tree (Expression (Parent (Formal)))));
5569 Next_Formal (Formal);
5573 Make_Defining_Identifier (Loc, Chars => Subp_Name);
5576 Make_Procedure_Specification (Loc,
5577 Defining_Unit_Name => Proc_Id,
5578 Parameter_Specifications => Formal_List);
5580 Decl_List := New_List;
5582 Append_To (Decl_List,
5583 Make_Subprogram_Declaration (Loc, Proc_Spec));
5585 -- Can_Convert_Unconstrained_Function checked that the function
5586 -- has no local declarations except implicit label declarations.
5587 -- Copy these declarations to the built procedure.
5589 if Present (Declarations (N)) then
5590 Body_Decl_List := New_List;
5597 D := First (Declarations (N));
5598 while Present (D) loop
5599 pragma Assert (Nkind (D) = N_Implicit_Label_Declaration);
5602 Make_Implicit_Label_Declaration (Loc,
5603 Make_Defining_Identifier (Loc,
5604 Chars => Chars (Defining_Identifier (D))),
5605 Label_Construct => Empty);
5606 Append_To (Body_Decl_List, New_D);
5613 pragma Assert (Present (Handled_Statement_Sequence (Ret_Node)));
5616 Make_Subprogram_Body (Loc,
5617 Specification => Copy_Separate_Tree (Proc_Spec),
5618 Declarations => Body_Decl_List,
5619 Handled_Statement_Sequence =>
5620 Copy_Separate_Tree (Handled_Statement_Sequence (Ret_Node)));
5622 Set_Defining_Unit_Name (Specification (Proc_Body),
5623 Make_Defining_Identifier (Loc, Subp_Name));
5625 Append_To (Decl_List, Proc_Body);
5626 end Build_Procedure;
5630 New_Obj : constant Node_Id := Copy_Separate_Tree (Ret_Obj);
5632 Proc_Id : Entity_Id;
5633 Proc_Call : Node_Id;
5635 -- Start of processing for Split_Unconstrained_Function
5638 -- Build the associated procedure, analyze it and insert it before
5639 -- the function body N
5642 Scope : constant Entity_Id := Current_Scope;
5643 Decl_List : List_Id;
5646 Build_Procedure (Proc_Id, Decl_List);
5647 Insert_Actions (N, Decl_List);
5651 -- Build the call to the generated procedure
5654 Actual_List : constant List_Id := New_List;
5658 Append_To (Actual_List,
5659 New_Reference_To (Defining_Identifier (New_Obj), Loc));
5661 Formal := First_Formal (Spec_Id);
5662 while Present (Formal) loop
5663 Append_To (Actual_List, New_Reference_To (Formal, Loc));
5665 -- Avoid spurious warning on unreferenced formals
5667 Set_Referenced (Formal);
5668 Next_Formal (Formal);
5672 Make_Procedure_Call_Statement (Loc,
5673 Name => New_Reference_To (Proc_Id, Loc),
5674 Parameter_Associations => Actual_List);
5682 -- main_1__F1b (New_Obj, ...);
5687 Make_Block_Statement (Loc,
5688 Declarations => New_List (New_Obj),
5689 Handled_Statement_Sequence =>
5690 Make_Handled_Sequence_Of_Statements (Loc,
5691 Statements => New_List (
5695 Make_Simple_Return_Statement (Loc,
5698 (Defining_Identifier (New_Obj), Loc)))));
5700 Rewrite (Ret_Node, Blk_Stmt);
5701 end Split_Unconstrained_Function;
5703 -- Start of processing for Check_And_Build_Body_To_Inline
5706 -- Do not inline any subprogram that contains nested subprograms, since
5707 -- the backend inlining circuit seems to generate uninitialized
5708 -- references in this case. We know this happens in the case of front
5709 -- end ZCX support, but it also appears it can happen in other cases as
5710 -- well. The backend often rejects attempts to inline in the case of
5711 -- nested procedures anyway, so little if anything is lost by this.
5712 -- Note that this is test is for the benefit of the back-end. There is
5713 -- a separate test for front-end inlining that also rejects nested
5716 -- Do not do this test if errors have been detected, because in some
5717 -- error cases, this code blows up, and we don't need it anyway if
5718 -- there have been errors, since we won't get to the linker anyway.
5720 if Comes_From_Source (Body_Id)
5721 and then (Has_Pragma_Inline_Always (Spec_Id)
5722 or else Optimization_Level > 0)
5723 and then Serious_Errors_Detected = 0
5731 P_Ent := Scope (P_Ent);
5732 exit when No (P_Ent) or else P_Ent = Standard_Standard;
5734 if Is_Subprogram (P_Ent) then
5735 Set_Is_Inlined (P_Ent, False);
5737 if Comes_From_Source (P_Ent)
5738 and then Has_Pragma_Inline (P_Ent)
5741 ("cannot inline& (nested subprogram)?", N, P_Ent,
5742 Is_Serious => True);
5749 -- Build the body to inline only if really needed!
5751 if Check_Body_To_Inline (N, Spec_Id)
5752 and then Serious_Errors_Detected = 0
5754 if Returns_Unconstrained_Type (Spec_Id) then
5755 if Can_Split_Unconstrained_Function (N) then
5756 Split_Unconstrained_Function (N, Spec_Id);
5757 Build_Body_To_Inline (N, Spec_Id);
5758 Set_Is_Inlined (Spec_Id);
5761 Build_Body_To_Inline (N, Spec_Id);
5762 Set_Is_Inlined (Spec_Id);
5765 end Check_And_Build_Body_To_Inline;
5767 -----------------------
5768 -- Check_Conformance --
5769 -----------------------
5771 procedure Check_Conformance
5772 (New_Id : Entity_Id;
5774 Ctype : Conformance_Type;
5776 Conforms : out Boolean;
5777 Err_Loc : Node_Id := Empty;
5778 Get_Inst : Boolean := False;
5779 Skip_Controlling_Formals : Boolean := False)
5781 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
5782 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
5783 -- If Errmsg is True, then processing continues to post an error message
5784 -- for conformance error on given node. Two messages are output. The
5785 -- first message points to the previous declaration with a general "no
5786 -- conformance" message. The second is the detailed reason, supplied as
5787 -- Msg. The parameter N provide information for a possible & insertion
5788 -- in the message, and also provides the location for posting the
5789 -- message in the absence of a specified Err_Loc location.
5791 -----------------------
5792 -- Conformance_Error --
5793 -----------------------
5795 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
5802 if No (Err_Loc) then
5808 Error_Msg_Sloc := Sloc (Old_Id);
5811 when Type_Conformant =>
5812 Error_Msg_N -- CODEFIX
5813 ("not type conformant with declaration#!", Enode);
5815 when Mode_Conformant =>
5816 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5818 ("not mode conformant with operation inherited#!",
5822 ("not mode conformant with declaration#!", Enode);
5825 when Subtype_Conformant =>
5826 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5828 ("not subtype conformant with operation inherited#!",
5832 ("not subtype conformant with declaration#!", Enode);
5835 when Fully_Conformant =>
5836 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
5837 Error_Msg_N -- CODEFIX
5838 ("not fully conformant with operation inherited#!",
5841 Error_Msg_N -- CODEFIX
5842 ("not fully conformant with declaration#!", Enode);
5846 Error_Msg_NE (Msg, Enode, N);
5848 end Conformance_Error;
5852 Old_Type : constant Entity_Id := Etype (Old_Id);
5853 New_Type : constant Entity_Id := Etype (New_Id);
5854 Old_Formal : Entity_Id;
5855 New_Formal : Entity_Id;
5856 Access_Types_Match : Boolean;
5857 Old_Formal_Base : Entity_Id;
5858 New_Formal_Base : Entity_Id;
5860 -- Start of processing for Check_Conformance
5865 -- We need a special case for operators, since they don't appear
5868 if Ctype = Type_Conformant then
5869 if Ekind (New_Id) = E_Operator
5870 and then Operator_Matches_Spec (New_Id, Old_Id)
5876 -- If both are functions/operators, check return types conform
5878 if Old_Type /= Standard_Void_Type
5879 and then New_Type /= Standard_Void_Type
5882 -- If we are checking interface conformance we omit controlling
5883 -- arguments and result, because we are only checking the conformance
5884 -- of the remaining parameters.
5886 if Has_Controlling_Result (Old_Id)
5887 and then Has_Controlling_Result (New_Id)
5888 and then Skip_Controlling_Formals
5892 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
5893 Conformance_Error ("\return type does not match!", New_Id);
5897 -- Ada 2005 (AI-231): In case of anonymous access types check the
5898 -- null-exclusion and access-to-constant attributes match.
5900 if Ada_Version >= Ada_2005
5901 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
5903 (Can_Never_Be_Null (Old_Type) /= Can_Never_Be_Null (New_Type)
5904 or else Is_Access_Constant (Etype (Old_Type)) /=
5905 Is_Access_Constant (Etype (New_Type)))
5907 Conformance_Error ("\return type does not match!", New_Id);
5911 -- If either is a function/operator and the other isn't, error
5913 elsif Old_Type /= Standard_Void_Type
5914 or else New_Type /= Standard_Void_Type
5916 Conformance_Error ("\functions can only match functions!", New_Id);
5920 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
5921 -- If this is a renaming as body, refine error message to indicate that
5922 -- the conflict is with the original declaration. If the entity is not
5923 -- frozen, the conventions don't have to match, the one of the renamed
5924 -- entity is inherited.
5926 if Ctype >= Subtype_Conformant then
5927 if Convention (Old_Id) /= Convention (New_Id) then
5928 if not Is_Frozen (New_Id) then
5931 elsif Present (Err_Loc)
5932 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
5933 and then Present (Corresponding_Spec (Err_Loc))
5935 Error_Msg_Name_1 := Chars (New_Id);
5937 Name_Ada + Convention_Id'Pos (Convention (New_Id));
5938 Conformance_Error ("\prior declaration for% has convention %!");
5941 Conformance_Error ("\calling conventions do not match!");
5946 elsif Is_Formal_Subprogram (Old_Id)
5947 or else Is_Formal_Subprogram (New_Id)
5949 Conformance_Error ("\formal subprograms not allowed!");
5954 -- Deal with parameters
5956 -- Note: we use the entity information, rather than going directly
5957 -- to the specification in the tree. This is not only simpler, but
5958 -- absolutely necessary for some cases of conformance tests between
5959 -- operators, where the declaration tree simply does not exist!
5961 Old_Formal := First_Formal (Old_Id);
5962 New_Formal := First_Formal (New_Id);
5963 while Present (Old_Formal) and then Present (New_Formal) loop
5964 if Is_Controlling_Formal (Old_Formal)
5965 and then Is_Controlling_Formal (New_Formal)
5966 and then Skip_Controlling_Formals
5968 -- The controlling formals will have different types when
5969 -- comparing an interface operation with its match, but both
5970 -- or neither must be access parameters.
5972 if Is_Access_Type (Etype (Old_Formal))
5974 Is_Access_Type (Etype (New_Formal))
5976 goto Skip_Controlling_Formal;
5979 ("\access parameter does not match!", New_Formal);
5983 -- Ada 2012: Mode conformance also requires that formal parameters
5984 -- be both aliased, or neither.
5986 if Ctype >= Mode_Conformant and then Ada_Version >= Ada_2012 then
5987 if Is_Aliased (Old_Formal) /= Is_Aliased (New_Formal) then
5989 ("\aliased parameter mismatch!", New_Formal);
5993 if Ctype = Fully_Conformant then
5995 -- Names must match. Error message is more accurate if we do
5996 -- this before checking that the types of the formals match.
5998 if Chars (Old_Formal) /= Chars (New_Formal) then
5999 Conformance_Error ("\name & does not match!", New_Formal);
6001 -- Set error posted flag on new formal as well to stop
6002 -- junk cascaded messages in some cases.
6004 Set_Error_Posted (New_Formal);
6008 -- Null exclusion must match
6010 if Null_Exclusion_Present (Parent (Old_Formal))
6012 Null_Exclusion_Present (Parent (New_Formal))
6014 -- Only give error if both come from source. This should be
6015 -- investigated some time, since it should not be needed ???
6017 if Comes_From_Source (Old_Formal)
6019 Comes_From_Source (New_Formal)
6022 ("\null exclusion for & does not match", New_Formal);
6024 -- Mark error posted on the new formal to avoid duplicated
6025 -- complaint about types not matching.
6027 Set_Error_Posted (New_Formal);
6032 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
6033 -- case occurs whenever a subprogram is being renamed and one of its
6034 -- parameters imposes a null exclusion. For example:
6036 -- type T is null record;
6037 -- type Acc_T is access T;
6038 -- subtype Acc_T_Sub is Acc_T;
6040 -- procedure P (Obj : not null Acc_T_Sub); -- itype
6041 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
6044 Old_Formal_Base := Etype (Old_Formal);
6045 New_Formal_Base := Etype (New_Formal);
6048 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
6049 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
6052 Access_Types_Match := Ada_Version >= Ada_2005
6054 -- Ensure that this rule is only applied when New_Id is a
6055 -- renaming of Old_Id.
6057 and then Nkind (Parent (Parent (New_Id))) =
6058 N_Subprogram_Renaming_Declaration
6059 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
6060 and then Present (Entity (Name (Parent (Parent (New_Id)))))
6061 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
6063 -- Now handle the allowed access-type case
6065 and then Is_Access_Type (Old_Formal_Base)
6066 and then Is_Access_Type (New_Formal_Base)
6068 -- The type kinds must match. The only exception occurs with
6069 -- multiple generics of the form:
6072 -- type F is private; type A is private;
6073 -- type F_Ptr is access F; type A_Ptr is access A;
6074 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
6075 -- package F_Pack is ... package A_Pack is
6076 -- package F_Inst is
6077 -- new F_Pack (A, A_Ptr, A_P);
6079 -- When checking for conformance between the parameters of A_P
6080 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
6081 -- because the compiler has transformed A_Ptr into a subtype of
6082 -- F_Ptr. We catch this case in the code below.
6084 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
6086 (Is_Generic_Type (Old_Formal_Base)
6087 and then Is_Generic_Type (New_Formal_Base)
6088 and then Is_Internal (New_Formal_Base)
6089 and then Etype (Etype (New_Formal_Base)) =
6091 and then Directly_Designated_Type (Old_Formal_Base) =
6092 Directly_Designated_Type (New_Formal_Base)
6093 and then ((Is_Itype (Old_Formal_Base)
6094 and then Can_Never_Be_Null (Old_Formal_Base))
6096 (Is_Itype (New_Formal_Base)
6097 and then Can_Never_Be_Null (New_Formal_Base)));
6099 -- Types must always match. In the visible part of an instance,
6100 -- usual overloading rules for dispatching operations apply, and
6101 -- we check base types (not the actual subtypes).
6103 if In_Instance_Visible_Part
6104 and then Is_Dispatching_Operation (New_Id)
6106 if not Conforming_Types
6107 (T1 => Base_Type (Etype (Old_Formal)),
6108 T2 => Base_Type (Etype (New_Formal)),
6110 Get_Inst => Get_Inst)
6111 and then not Access_Types_Match
6113 Conformance_Error ("\type of & does not match!", New_Formal);
6117 elsif not Conforming_Types
6118 (T1 => Old_Formal_Base,
6119 T2 => New_Formal_Base,
6121 Get_Inst => Get_Inst)
6122 and then not Access_Types_Match
6124 -- Don't give error message if old type is Any_Type. This test
6125 -- avoids some cascaded errors, e.g. in case of a bad spec.
6127 if Errmsg and then Old_Formal_Base = Any_Type then
6130 Conformance_Error ("\type of & does not match!", New_Formal);
6136 -- For mode conformance, mode must match
6138 if Ctype >= Mode_Conformant then
6139 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
6140 if not Ekind_In (New_Id, E_Function, E_Procedure)
6141 or else not Is_Primitive_Wrapper (New_Id)
6143 Conformance_Error ("\mode of & does not match!", New_Formal);
6147 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
6149 if Is_Protected_Type
6150 (Corresponding_Concurrent_Type (T))
6152 Error_Msg_PT (T, New_Id);
6155 ("\mode of & does not match!", New_Formal);
6162 -- Part of mode conformance for access types is having the same
6163 -- constant modifier.
6165 elsif Access_Types_Match
6166 and then Is_Access_Constant (Old_Formal_Base) /=
6167 Is_Access_Constant (New_Formal_Base)
6170 ("\constant modifier does not match!", New_Formal);
6175 if Ctype >= Subtype_Conformant then
6177 -- Ada 2005 (AI-231): In case of anonymous access types check
6178 -- the null-exclusion and access-to-constant attributes must
6179 -- match. For null exclusion, we test the types rather than the
6180 -- formals themselves, since the attribute is only set reliably
6181 -- on the formals in the Ada 95 case, and we exclude the case
6182 -- where Old_Formal is marked as controlling, to avoid errors
6183 -- when matching completing bodies with dispatching declarations
6184 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
6186 if Ada_Version >= Ada_2005
6187 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
6188 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
6190 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
6191 Can_Never_Be_Null (Etype (New_Formal))
6193 not Is_Controlling_Formal (Old_Formal))
6195 Is_Access_Constant (Etype (Old_Formal)) /=
6196 Is_Access_Constant (Etype (New_Formal)))
6198 -- Do not complain if error already posted on New_Formal. This
6199 -- avoids some redundant error messages.
6201 and then not Error_Posted (New_Formal)
6203 -- It is allowed to omit the null-exclusion in case of stream
6204 -- attribute subprograms. We recognize stream subprograms
6205 -- through their TSS-generated suffix.
6208 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
6211 if TSS_Name /= TSS_Stream_Read
6212 and then TSS_Name /= TSS_Stream_Write
6213 and then TSS_Name /= TSS_Stream_Input
6214 and then TSS_Name /= TSS_Stream_Output
6216 -- Here we have a definite conformance error. It is worth
6217 -- special casing the error message for the case of a
6218 -- controlling formal (which excludes null).
6220 if Is_Controlling_Formal (New_Formal) then
6221 Error_Msg_Node_2 := Scope (New_Formal);
6223 ("\controlling formal& of& excludes null, "
6224 & "declaration must exclude null as well",
6227 -- Normal case (couldn't we give more detail here???)
6231 ("\type of & does not match!", New_Formal);
6240 -- Full conformance checks
6242 if Ctype = Fully_Conformant then
6244 -- We have checked already that names match
6246 if Parameter_Mode (Old_Formal) = E_In_Parameter then
6248 -- Check default expressions for in parameters
6251 NewD : constant Boolean :=
6252 Present (Default_Value (New_Formal));
6253 OldD : constant Boolean :=
6254 Present (Default_Value (Old_Formal));
6256 if NewD or OldD then
6258 -- The old default value has been analyzed because the
6259 -- current full declaration will have frozen everything
6260 -- before. The new default value has not been analyzed,
6261 -- so analyze it now before we check for conformance.
6264 Push_Scope (New_Id);
6265 Preanalyze_Spec_Expression
6266 (Default_Value (New_Formal), Etype (New_Formal));
6270 if not (NewD and OldD)
6271 or else not Fully_Conformant_Expressions
6272 (Default_Value (Old_Formal),
6273 Default_Value (New_Formal))
6276 ("\default expression for & does not match!",
6285 -- A couple of special checks for Ada 83 mode. These checks are
6286 -- skipped if either entity is an operator in package Standard,
6287 -- or if either old or new instance is not from the source program.
6289 if Ada_Version = Ada_83
6290 and then Sloc (Old_Id) > Standard_Location
6291 and then Sloc (New_Id) > Standard_Location
6292 and then Comes_From_Source (Old_Id)
6293 and then Comes_From_Source (New_Id)
6296 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
6297 New_Param : constant Node_Id := Declaration_Node (New_Formal);
6300 -- Explicit IN must be present or absent in both cases. This
6301 -- test is required only in the full conformance case.
6303 if In_Present (Old_Param) /= In_Present (New_Param)
6304 and then Ctype = Fully_Conformant
6307 ("\(Ada 83) IN must appear in both declarations",
6312 -- Grouping (use of comma in param lists) must be the same
6313 -- This is where we catch a misconformance like:
6316 -- A : Integer; B : Integer
6318 -- which are represented identically in the tree except
6319 -- for the setting of the flags More_Ids and Prev_Ids.
6321 if More_Ids (Old_Param) /= More_Ids (New_Param)
6322 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
6325 ("\grouping of & does not match!", New_Formal);
6331 -- This label is required when skipping controlling formals
6333 <<Skip_Controlling_Formal>>
6335 Next_Formal (Old_Formal);
6336 Next_Formal (New_Formal);
6339 if Present (Old_Formal) then
6340 Conformance_Error ("\too few parameters!");
6343 elsif Present (New_Formal) then
6344 Conformance_Error ("\too many parameters!", New_Formal);
6347 end Check_Conformance;
6349 -----------------------
6350 -- Check_Conventions --
6351 -----------------------
6353 procedure Check_Conventions (Typ : Entity_Id) is
6354 Ifaces_List : Elist_Id;
6356 procedure Check_Convention (Op : Entity_Id);
6357 -- Verify that the convention of inherited dispatching operation Op is
6358 -- consistent among all subprograms it overrides. In order to minimize
6359 -- the search, Search_From is utilized to designate a specific point in
6360 -- the list rather than iterating over the whole list once more.
6362 ----------------------
6363 -- Check_Convention --
6364 ----------------------
6366 procedure Check_Convention (Op : Entity_Id) is
6367 function Convention_Of (Id : Entity_Id) return Convention_Id;
6368 -- Given an entity, return its convention. The function treats Ghost
6369 -- as convention Ada because the two have the same dynamic semantics.
6375 function Convention_Of (Id : Entity_Id) return Convention_Id is
6376 Conv : constant Convention_Id := Convention (Id);
6378 if Conv = Convention_Ghost then
6379 return Convention_Ada;
6387 Op_Conv : constant Convention_Id := Convention_Of (Op);
6388 Iface_Conv : Convention_Id;
6389 Iface_Elmt : Elmt_Id;
6390 Iface_Prim_Elmt : Elmt_Id;
6391 Iface_Prim : Entity_Id;
6393 -- Start of processing for Check_Convention
6396 Iface_Elmt := First_Elmt (Ifaces_List);
6397 while Present (Iface_Elmt) loop
6399 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
6400 while Present (Iface_Prim_Elmt) loop
6401 Iface_Prim := Node (Iface_Prim_Elmt);
6402 Iface_Conv := Convention_Of (Iface_Prim);
6404 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
6405 and then Iface_Conv /= Op_Conv
6408 ("inconsistent conventions in primitive operations", Typ);
6410 Error_Msg_Name_1 := Chars (Op);
6411 Error_Msg_Name_2 := Get_Convention_Name (Op_Conv);
6412 Error_Msg_Sloc := Sloc (Op);
6414 if Comes_From_Source (Op) or else No (Alias (Op)) then
6415 if not Present (Overridden_Operation (Op)) then
6416 Error_Msg_N ("\\primitive % defined #", Typ);
6419 ("\\overriding operation % with " &
6420 "convention % defined #", Typ);
6423 else pragma Assert (Present (Alias (Op)));
6424 Error_Msg_Sloc := Sloc (Alias (Op));
6426 ("\\inherited operation % with " &
6427 "convention % defined #", Typ);
6430 Error_Msg_Name_1 := Chars (Op);
6431 Error_Msg_Name_2 := Get_Convention_Name (Iface_Conv);
6432 Error_Msg_Sloc := Sloc (Iface_Prim);
6434 ("\\overridden operation % with " &
6435 "convention % defined #", Typ);
6437 -- Avoid cascading errors
6442 Next_Elmt (Iface_Prim_Elmt);
6445 Next_Elmt (Iface_Elmt);
6447 end Check_Convention;
6451 Prim_Op : Entity_Id;
6452 Prim_Op_Elmt : Elmt_Id;
6454 -- Start of processing for Check_Conventions
6457 if not Has_Interfaces (Typ) then
6461 Collect_Interfaces (Typ, Ifaces_List);
6463 -- The algorithm checks every overriding dispatching operation against
6464 -- all the corresponding overridden dispatching operations, detecting
6465 -- differences in conventions.
6467 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
6468 while Present (Prim_Op_Elmt) loop
6469 Prim_Op := Node (Prim_Op_Elmt);
6471 -- A small optimization: skip the predefined dispatching operations
6472 -- since they always have the same convention.
6474 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
6475 Check_Convention (Prim_Op);
6478 Next_Elmt (Prim_Op_Elmt);
6480 end Check_Conventions;
6482 ------------------------------
6483 -- Check_Delayed_Subprogram --
6484 ------------------------------
6486 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
6489 procedure Possible_Freeze (T : Entity_Id);
6490 -- T is the type of either a formal parameter or of the return type.
6491 -- If T is not yet frozen and needs a delayed freeze, then the
6492 -- subprogram itself must be delayed. If T is the limited view of an
6493 -- incomplete type the subprogram must be frozen as well, because
6494 -- T may depend on local types that have not been frozen yet.
6496 ---------------------
6497 -- Possible_Freeze --
6498 ---------------------
6500 procedure Possible_Freeze (T : Entity_Id) is
6502 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
6503 Set_Has_Delayed_Freeze (Designator);
6505 elsif Is_Access_Type (T)
6506 and then Has_Delayed_Freeze (Designated_Type (T))
6507 and then not Is_Frozen (Designated_Type (T))
6509 Set_Has_Delayed_Freeze (Designator);
6511 elsif Ekind (T) = E_Incomplete_Type and then From_With_Type (T) then
6512 Set_Has_Delayed_Freeze (Designator);
6514 -- AI05-0151: In Ada 2012, Incomplete types can appear in the profile
6515 -- of a subprogram or entry declaration.
6517 elsif Ekind (T) = E_Incomplete_Type
6518 and then Ada_Version >= Ada_2012
6520 Set_Has_Delayed_Freeze (Designator);
6523 end Possible_Freeze;
6525 -- Start of processing for Check_Delayed_Subprogram
6528 -- All subprograms, including abstract subprograms, may need a freeze
6529 -- node if some formal type or the return type needs one.
6531 Possible_Freeze (Etype (Designator));
6532 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
6534 -- Need delayed freeze if any of the formal types themselves need
6535 -- a delayed freeze and are not yet frozen.
6537 F := First_Formal (Designator);
6538 while Present (F) loop
6539 Possible_Freeze (Etype (F));
6540 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
6544 -- Mark functions that return by reference. Note that it cannot be
6545 -- done for delayed_freeze subprograms because the underlying
6546 -- returned type may not be known yet (for private types)
6548 if not Has_Delayed_Freeze (Designator) and then Expander_Active then
6550 Typ : constant Entity_Id := Etype (Designator);
6551 Utyp : constant Entity_Id := Underlying_Type (Typ);
6553 if Is_Immutably_Limited_Type (Typ) then
6554 Set_Returns_By_Ref (Designator);
6555 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
6556 Set_Returns_By_Ref (Designator);
6560 end Check_Delayed_Subprogram;
6562 ------------------------------------
6563 -- Check_Discriminant_Conformance --
6564 ------------------------------------
6566 procedure Check_Discriminant_Conformance
6571 Old_Discr : Entity_Id := First_Discriminant (Prev);
6572 New_Discr : Node_Id := First (Discriminant_Specifications (N));
6573 New_Discr_Id : Entity_Id;
6574 New_Discr_Type : Entity_Id;
6576 procedure Conformance_Error (Msg : String; N : Node_Id);
6577 -- Post error message for conformance error on given node. Two messages
6578 -- are output. The first points to the previous declaration with a
6579 -- general "no conformance" message. The second is the detailed reason,
6580 -- supplied as Msg. The parameter N provide information for a possible
6581 -- & insertion in the message.
6583 -----------------------
6584 -- Conformance_Error --
6585 -----------------------
6587 procedure Conformance_Error (Msg : String; N : Node_Id) is
6589 Error_Msg_Sloc := Sloc (Prev_Loc);
6590 Error_Msg_N -- CODEFIX
6591 ("not fully conformant with declaration#!", N);
6592 Error_Msg_NE (Msg, N, N);
6593 end Conformance_Error;
6595 -- Start of processing for Check_Discriminant_Conformance
6598 while Present (Old_Discr) and then Present (New_Discr) loop
6599 New_Discr_Id := Defining_Identifier (New_Discr);
6601 -- The subtype mark of the discriminant on the full type has not
6602 -- been analyzed so we do it here. For an access discriminant a new
6605 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
6607 Access_Definition (N, Discriminant_Type (New_Discr));
6610 Analyze (Discriminant_Type (New_Discr));
6611 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
6613 -- Ada 2005: if the discriminant definition carries a null
6614 -- exclusion, create an itype to check properly for consistency
6615 -- with partial declaration.
6617 if Is_Access_Type (New_Discr_Type)
6618 and then Null_Exclusion_Present (New_Discr)
6621 Create_Null_Excluding_Itype
6622 (T => New_Discr_Type,
6623 Related_Nod => New_Discr,
6624 Scope_Id => Current_Scope);
6628 if not Conforming_Types
6629 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
6631 Conformance_Error ("type of & does not match!", New_Discr_Id);
6634 -- Treat the new discriminant as an occurrence of the old one,
6635 -- for navigation purposes, and fill in some semantic
6636 -- information, for completeness.
6638 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
6639 Set_Etype (New_Discr_Id, Etype (Old_Discr));
6640 Set_Scope (New_Discr_Id, Scope (Old_Discr));
6645 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
6646 Conformance_Error ("name & does not match!", New_Discr_Id);
6650 -- Default expressions must match
6653 NewD : constant Boolean :=
6654 Present (Expression (New_Discr));
6655 OldD : constant Boolean :=
6656 Present (Expression (Parent (Old_Discr)));
6659 if NewD or OldD then
6661 -- The old default value has been analyzed and expanded,
6662 -- because the current full declaration will have frozen
6663 -- everything before. The new default values have not been
6664 -- expanded, so expand now to check conformance.
6667 Preanalyze_Spec_Expression
6668 (Expression (New_Discr), New_Discr_Type);
6671 if not (NewD and OldD)
6672 or else not Fully_Conformant_Expressions
6673 (Expression (Parent (Old_Discr)),
6674 Expression (New_Discr))
6678 ("default expression for & does not match!",
6685 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
6687 if Ada_Version = Ada_83 then
6689 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
6692 -- Grouping (use of comma in param lists) must be the same
6693 -- This is where we catch a misconformance like:
6696 -- A : Integer; B : Integer
6698 -- which are represented identically in the tree except
6699 -- for the setting of the flags More_Ids and Prev_Ids.
6701 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
6702 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
6705 ("grouping of & does not match!", New_Discr_Id);
6711 Next_Discriminant (Old_Discr);
6715 if Present (Old_Discr) then
6716 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
6719 elsif Present (New_Discr) then
6721 ("too many discriminants!", Defining_Identifier (New_Discr));
6724 end Check_Discriminant_Conformance;
6726 ----------------------------
6727 -- Check_Fully_Conformant --
6728 ----------------------------
6730 procedure Check_Fully_Conformant
6731 (New_Id : Entity_Id;
6733 Err_Loc : Node_Id := Empty)
6736 pragma Warnings (Off, Result);
6739 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
6740 end Check_Fully_Conformant;
6742 ---------------------------
6743 -- Check_Mode_Conformant --
6744 ---------------------------
6746 procedure Check_Mode_Conformant
6747 (New_Id : Entity_Id;
6749 Err_Loc : Node_Id := Empty;
6750 Get_Inst : Boolean := False)
6753 pragma Warnings (Off, Result);
6756 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
6757 end Check_Mode_Conformant;
6759 --------------------------------
6760 -- Check_Overriding_Indicator --
6761 --------------------------------
6763 procedure Check_Overriding_Indicator
6765 Overridden_Subp : Entity_Id;
6766 Is_Primitive : Boolean)
6772 -- No overriding indicator for literals
6774 if Ekind (Subp) = E_Enumeration_Literal then
6777 elsif Ekind (Subp) = E_Entry then
6778 Decl := Parent (Subp);
6780 -- No point in analyzing a malformed operator
6782 elsif Nkind (Subp) = N_Defining_Operator_Symbol
6783 and then Error_Posted (Subp)
6788 Decl := Unit_Declaration_Node (Subp);
6791 if Nkind_In (Decl, N_Subprogram_Body,
6792 N_Subprogram_Body_Stub,
6793 N_Subprogram_Declaration,
6794 N_Abstract_Subprogram_Declaration,
6795 N_Subprogram_Renaming_Declaration)
6797 Spec := Specification (Decl);
6799 elsif Nkind (Decl) = N_Entry_Declaration then
6806 -- The overriding operation is type conformant with the overridden one,
6807 -- but the names of the formals are not required to match. If the names
6808 -- appear permuted in the overriding operation, this is a possible
6809 -- source of confusion that is worth diagnosing. Controlling formals
6810 -- often carry names that reflect the type, and it is not worthwhile
6811 -- requiring that their names match.
6813 if Present (Overridden_Subp)
6814 and then Nkind (Subp) /= N_Defining_Operator_Symbol
6821 Form1 := First_Formal (Subp);
6822 Form2 := First_Formal (Overridden_Subp);
6824 -- If the overriding operation is a synchronized operation, skip
6825 -- the first parameter of the overridden operation, which is
6826 -- implicit in the new one. If the operation is declared in the
6827 -- body it is not primitive and all formals must match.
6829 if Is_Concurrent_Type (Scope (Subp))
6830 and then Is_Tagged_Type (Scope (Subp))
6831 and then not Has_Completion (Scope (Subp))
6833 Form2 := Next_Formal (Form2);
6836 if Present (Form1) then
6837 Form1 := Next_Formal (Form1);
6838 Form2 := Next_Formal (Form2);
6841 while Present (Form1) loop
6842 if not Is_Controlling_Formal (Form1)
6843 and then Present (Next_Formal (Form2))
6844 and then Chars (Form1) = Chars (Next_Formal (Form2))
6846 Error_Msg_Node_2 := Alias (Overridden_Subp);
6847 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6849 ("& does not match corresponding formal of&#",
6854 Next_Formal (Form1);
6855 Next_Formal (Form2);
6860 -- If there is an overridden subprogram, then check that there is no
6861 -- "not overriding" indicator, and mark the subprogram as overriding.
6862 -- This is not done if the overridden subprogram is marked as hidden,
6863 -- which can occur for the case of inherited controlled operations
6864 -- (see Derive_Subprogram), unless the inherited subprogram's parent
6865 -- subprogram is not itself hidden. (Note: This condition could probably
6866 -- be simplified, leaving out the testing for the specific controlled
6867 -- cases, but it seems safer and clearer this way, and echoes similar
6868 -- special-case tests of this kind in other places.)
6870 if Present (Overridden_Subp)
6871 and then (not Is_Hidden (Overridden_Subp)
6873 (Nam_In (Chars (Overridden_Subp), Name_Initialize,
6876 and then Present (Alias (Overridden_Subp))
6877 and then not Is_Hidden (Alias (Overridden_Subp))))
6879 if Must_Not_Override (Spec) then
6880 Error_Msg_Sloc := Sloc (Overridden_Subp);
6882 if Ekind (Subp) = E_Entry then
6884 ("entry & overrides inherited operation #", Spec, Subp);
6887 ("subprogram & overrides inherited operation #", Spec, Subp);
6890 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
6891 -- as an extension of Root_Controlled, and thus has a useless Adjust
6892 -- operation. This operation should not be inherited by other limited
6893 -- controlled types. An explicit Adjust for them is not overriding.
6895 elsif Must_Override (Spec)
6896 and then Chars (Overridden_Subp) = Name_Adjust
6897 and then Is_Limited_Type (Etype (First_Formal (Subp)))
6898 and then Present (Alias (Overridden_Subp))
6900 Is_Predefined_File_Name
6901 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))))
6903 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6905 elsif Is_Subprogram (Subp) then
6906 if Is_Init_Proc (Subp) then
6909 elsif No (Overridden_Operation (Subp)) then
6911 -- For entities generated by Derive_Subprograms the overridden
6912 -- operation is the inherited primitive (which is available
6913 -- through the attribute alias)
6915 if (Is_Dispatching_Operation (Subp)
6916 or else Is_Dispatching_Operation (Overridden_Subp))
6917 and then not Comes_From_Source (Overridden_Subp)
6918 and then Find_Dispatching_Type (Overridden_Subp) =
6919 Find_Dispatching_Type (Subp)
6920 and then Present (Alias (Overridden_Subp))
6921 and then Comes_From_Source (Alias (Overridden_Subp))
6923 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
6926 Set_Overridden_Operation (Subp, Overridden_Subp);
6931 -- If primitive flag is set or this is a protected operation, then
6932 -- the operation is overriding at the point of its declaration, so
6933 -- warn if necessary. Otherwise it may have been declared before the
6934 -- operation it overrides and no check is required.
6937 and then not Must_Override (Spec)
6938 and then (Is_Primitive
6939 or else Ekind (Scope (Subp)) = E_Protected_Type)
6941 Style.Missing_Overriding (Decl, Subp);
6944 -- If Subp is an operator, it may override a predefined operation, if
6945 -- it is defined in the same scope as the type to which it applies.
6946 -- In that case Overridden_Subp is empty because of our implicit
6947 -- representation for predefined operators. We have to check whether the
6948 -- signature of Subp matches that of a predefined operator. Note that
6949 -- first argument provides the name of the operator, and the second
6950 -- argument the signature that may match that of a standard operation.
6951 -- If the indicator is overriding, then the operator must match a
6952 -- predefined signature, because we know already that there is no
6953 -- explicit overridden operation.
6955 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
6956 if Must_Not_Override (Spec) then
6958 -- If this is not a primitive or a protected subprogram, then
6959 -- "not overriding" is illegal.
6962 and then Ekind (Scope (Subp)) /= E_Protected_Type
6965 ("overriding indicator only allowed "
6966 & "if subprogram is primitive", Subp);
6968 elsif Can_Override_Operator (Subp) then
6970 ("subprogram& overrides predefined operator ", Spec, Subp);
6973 elsif Must_Override (Spec) then
6974 if No (Overridden_Operation (Subp))
6975 and then not Can_Override_Operator (Subp)
6977 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
6980 elsif not Error_Posted (Subp)
6981 and then Style_Check
6982 and then Can_Override_Operator (Subp)
6984 not Is_Predefined_File_Name
6985 (Unit_File_Name (Get_Source_Unit (Subp)))
6987 -- If style checks are enabled, indicate that the indicator is
6988 -- missing. However, at the point of declaration, the type of
6989 -- which this is a primitive operation may be private, in which
6990 -- case the indicator would be premature.
6992 if Has_Private_Declaration (Etype (Subp))
6993 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
6997 Style.Missing_Overriding (Decl, Subp);
7001 elsif Must_Override (Spec) then
7002 if Ekind (Subp) = E_Entry then
7003 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
7005 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
7008 -- If the operation is marked "not overriding" and it's not primitive
7009 -- then an error is issued, unless this is an operation of a task or
7010 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
7011 -- has been specified have already been checked above.
7013 elsif Must_Not_Override (Spec)
7014 and then not Is_Primitive
7015 and then Ekind (Subp) /= E_Entry
7016 and then Ekind (Scope (Subp)) /= E_Protected_Type
7019 ("overriding indicator only allowed if subprogram is primitive",
7023 end Check_Overriding_Indicator;
7029 -- Note: this procedure needs to know far too much about how the expander
7030 -- messes with exceptions. The use of the flag Exception_Junk and the
7031 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
7032 -- works, but is not very clean. It would be better if the expansion
7033 -- routines would leave Original_Node working nicely, and we could use
7034 -- Original_Node here to ignore all the peculiar expander messing ???
7036 procedure Check_Returns
7040 Proc : Entity_Id := Empty)
7044 procedure Check_Statement_Sequence (L : List_Id);
7045 -- Internal recursive procedure to check a list of statements for proper
7046 -- termination by a return statement (or a transfer of control or a
7047 -- compound statement that is itself internally properly terminated).
7049 ------------------------------
7050 -- Check_Statement_Sequence --
7051 ------------------------------
7053 procedure Check_Statement_Sequence (L : List_Id) is
7058 Raise_Exception_Call : Boolean;
7059 -- Set True if statement sequence terminated by Raise_Exception call
7060 -- or a Reraise_Occurrence call.
7063 Raise_Exception_Call := False;
7065 -- Get last real statement
7067 Last_Stm := Last (L);
7069 -- Deal with digging out exception handler statement sequences that
7070 -- have been transformed by the local raise to goto optimization.
7071 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
7072 -- optimization has occurred, we are looking at something like:
7075 -- original stmts in block
7079 -- goto L1; | omitted if No_Exception_Propagation
7084 -- goto L3; -- skip handler when exception not raised
7086 -- <<L1>> -- target label for local exception
7100 -- and what we have to do is to dig out the estmts1 and estmts2
7101 -- sequences (which were the original sequences of statements in
7102 -- the exception handlers) and check them.
7104 if Nkind (Last_Stm) = N_Label and then Exception_Junk (Last_Stm) then
7109 exit when Nkind (Stm) /= N_Block_Statement;
7110 exit when not Exception_Junk (Stm);
7113 exit when Nkind (Stm) /= N_Label;
7114 exit when not Exception_Junk (Stm);
7115 Check_Statement_Sequence
7116 (Statements (Handled_Statement_Sequence (Next (Stm))));
7121 exit when Nkind (Stm) /= N_Goto_Statement;
7122 exit when not Exception_Junk (Stm);
7126 -- Don't count pragmas
7128 while Nkind (Last_Stm) = N_Pragma
7130 -- Don't count call to SS_Release (can happen after Raise_Exception)
7133 (Nkind (Last_Stm) = N_Procedure_Call_Statement
7135 Nkind (Name (Last_Stm)) = N_Identifier
7137 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
7139 -- Don't count exception junk
7142 (Nkind_In (Last_Stm, N_Goto_Statement,
7144 N_Object_Declaration)
7145 and then Exception_Junk (Last_Stm))
7146 or else Nkind (Last_Stm) in N_Push_xxx_Label
7147 or else Nkind (Last_Stm) in N_Pop_xxx_Label
7149 -- Inserted code, such as finalization calls, is irrelevant: we only
7150 -- need to check original source.
7152 or else Is_Rewrite_Insertion (Last_Stm)
7157 -- Here we have the "real" last statement
7159 Kind := Nkind (Last_Stm);
7161 -- Transfer of control, OK. Note that in the No_Return procedure
7162 -- case, we already diagnosed any explicit return statements, so
7163 -- we can treat them as OK in this context.
7165 if Is_Transfer (Last_Stm) then
7168 -- Check cases of explicit non-indirect procedure calls
7170 elsif Kind = N_Procedure_Call_Statement
7171 and then Is_Entity_Name (Name (Last_Stm))
7173 -- Check call to Raise_Exception procedure which is treated
7174 -- specially, as is a call to Reraise_Occurrence.
7176 -- We suppress the warning in these cases since it is likely that
7177 -- the programmer really does not expect to deal with the case
7178 -- of Null_Occurrence, and thus would find a warning about a
7179 -- missing return curious, and raising Program_Error does not
7180 -- seem such a bad behavior if this does occur.
7182 -- Note that in the Ada 2005 case for Raise_Exception, the actual
7183 -- behavior will be to raise Constraint_Error (see AI-329).
7185 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
7187 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
7189 Raise_Exception_Call := True;
7191 -- For Raise_Exception call, test first argument, if it is
7192 -- an attribute reference for a 'Identity call, then we know
7193 -- that the call cannot possibly return.
7196 Arg : constant Node_Id :=
7197 Original_Node (First_Actual (Last_Stm));
7199 if Nkind (Arg) = N_Attribute_Reference
7200 and then Attribute_Name (Arg) = Name_Identity
7207 -- If statement, need to look inside if there is an else and check
7208 -- each constituent statement sequence for proper termination.
7210 elsif Kind = N_If_Statement
7211 and then Present (Else_Statements (Last_Stm))
7213 Check_Statement_Sequence (Then_Statements (Last_Stm));
7214 Check_Statement_Sequence (Else_Statements (Last_Stm));
7216 if Present (Elsif_Parts (Last_Stm)) then
7218 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
7221 while Present (Elsif_Part) loop
7222 Check_Statement_Sequence (Then_Statements (Elsif_Part));
7230 -- Case statement, check each case for proper termination
7232 elsif Kind = N_Case_Statement then
7236 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
7237 while Present (Case_Alt) loop
7238 Check_Statement_Sequence (Statements (Case_Alt));
7239 Next_Non_Pragma (Case_Alt);
7245 -- Block statement, check its handled sequence of statements
7247 elsif Kind = N_Block_Statement then
7253 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
7262 -- Loop statement. If there is an iteration scheme, we can definitely
7263 -- fall out of the loop. Similarly if there is an exit statement, we
7264 -- can fall out. In either case we need a following return.
7266 elsif Kind = N_Loop_Statement then
7267 if Present (Iteration_Scheme (Last_Stm))
7268 or else Has_Exit (Entity (Identifier (Last_Stm)))
7272 -- A loop with no exit statement or iteration scheme is either
7273 -- an infinite loop, or it has some other exit (raise/return).
7274 -- In either case, no warning is required.
7280 -- Timed entry call, check entry call and delay alternatives
7282 -- Note: in expanded code, the timed entry call has been converted
7283 -- to a set of expanded statements on which the check will work
7284 -- correctly in any case.
7286 elsif Kind = N_Timed_Entry_Call then
7288 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
7289 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
7292 -- If statement sequence of entry call alternative is missing,
7293 -- then we can definitely fall through, and we post the error
7294 -- message on the entry call alternative itself.
7296 if No (Statements (ECA)) then
7299 -- If statement sequence of delay alternative is missing, then
7300 -- we can definitely fall through, and we post the error
7301 -- message on the delay alternative itself.
7303 -- Note: if both ECA and DCA are missing the return, then we
7304 -- post only one message, should be enough to fix the bugs.
7305 -- If not we will get a message next time on the DCA when the
7308 elsif No (Statements (DCA)) then
7311 -- Else check both statement sequences
7314 Check_Statement_Sequence (Statements (ECA));
7315 Check_Statement_Sequence (Statements (DCA));
7320 -- Conditional entry call, check entry call and else part
7322 -- Note: in expanded code, the conditional entry call has been
7323 -- converted to a set of expanded statements on which the check
7324 -- will work correctly in any case.
7326 elsif Kind = N_Conditional_Entry_Call then
7328 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
7331 -- If statement sequence of entry call alternative is missing,
7332 -- then we can definitely fall through, and we post the error
7333 -- message on the entry call alternative itself.
7335 if No (Statements (ECA)) then
7338 -- Else check statement sequence and else part
7341 Check_Statement_Sequence (Statements (ECA));
7342 Check_Statement_Sequence (Else_Statements (Last_Stm));
7348 -- If we fall through, issue appropriate message
7351 if not Raise_Exception_Call then
7353 ("RETURN statement missing following this statement??!",
7356 ("\Program_Error may be raised at run time??!",
7360 -- Note: we set Err even though we have not issued a warning
7361 -- because we still have a case of a missing return. This is
7362 -- an extremely marginal case, probably will never be noticed
7363 -- but we might as well get it right.
7367 -- Otherwise we have the case of a procedure marked No_Return
7370 if not Raise_Exception_Call then
7372 ("implied return after this statement " &
7373 "will raise Program_Error??",
7376 ("\procedure & is marked as No_Return??!",
7381 RE : constant Node_Id :=
7382 Make_Raise_Program_Error (Sloc (Last_Stm),
7383 Reason => PE_Implicit_Return);
7385 Insert_After (Last_Stm, RE);
7389 end Check_Statement_Sequence;
7391 -- Start of processing for Check_Returns
7395 Check_Statement_Sequence (Statements (HSS));
7397 if Present (Exception_Handlers (HSS)) then
7398 Handler := First_Non_Pragma (Exception_Handlers (HSS));
7399 while Present (Handler) loop
7400 Check_Statement_Sequence (Statements (Handler));
7401 Next_Non_Pragma (Handler);
7406 ----------------------------
7407 -- Check_Subprogram_Order --
7408 ----------------------------
7410 procedure Check_Subprogram_Order (N : Node_Id) is
7412 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
7413 -- This is used to check if S1 > S2 in the sense required by this test,
7414 -- for example nameab < namec, but name2 < name10.
7416 -----------------------------
7417 -- Subprogram_Name_Greater --
7418 -----------------------------
7420 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
7425 -- Deal with special case where names are identical except for a
7426 -- numerical suffix. These are handled specially, taking the numeric
7427 -- ordering from the suffix into account.
7430 while S1 (L1) in '0' .. '9' loop
7435 while S2 (L2) in '0' .. '9' loop
7439 -- If non-numeric parts non-equal, do straight compare
7441 if S1 (S1'First .. L1) /= S2 (S2'First .. L2) then
7444 -- If non-numeric parts equal, compare suffixed numeric parts. Note
7445 -- that a missing suffix is treated as numeric zero in this test.
7449 while L1 < S1'Last loop
7451 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
7455 while L2 < S2'Last loop
7457 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
7462 end Subprogram_Name_Greater;
7464 -- Start of processing for Check_Subprogram_Order
7467 -- Check body in alpha order if this is option
7470 and then Style_Check_Order_Subprograms
7471 and then Nkind (N) = N_Subprogram_Body
7472 and then Comes_From_Source (N)
7473 and then In_Extended_Main_Source_Unit (N)
7477 renames Scope_Stack.Table
7478 (Scope_Stack.Last).Last_Subprogram_Name;
7480 Body_Id : constant Entity_Id :=
7481 Defining_Entity (Specification (N));
7484 Get_Decoded_Name_String (Chars (Body_Id));
7487 if Subprogram_Name_Greater
7488 (LSN.all, Name_Buffer (1 .. Name_Len))
7490 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
7496 LSN := new String'(Name_Buffer (1 .. Name_Len));
7499 end Check_Subprogram_Order;
7501 ------------------------------
7502 -- Check_Subtype_Conformant --
7503 ------------------------------
7505 procedure Check_Subtype_Conformant
7506 (New_Id : Entity_Id;
7508 Err_Loc : Node_Id := Empty;
7509 Skip_Controlling_Formals : Boolean := False;
7510 Get_Inst : Boolean := False)
7513 pragma Warnings (Off, Result);
7516 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
7517 Skip_Controlling_Formals => Skip_Controlling_Formals,
7518 Get_Inst => Get_Inst);
7519 end Check_Subtype_Conformant;
7521 ---------------------------
7522 -- Check_Type_Conformant --
7523 ---------------------------
7525 procedure Check_Type_Conformant
7526 (New_Id : Entity_Id;
7528 Err_Loc : Node_Id := Empty)
7531 pragma Warnings (Off, Result);
7534 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
7535 end Check_Type_Conformant;
7537 ---------------------------
7538 -- Can_Override_Operator --
7539 ---------------------------
7541 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
7545 if Nkind (Subp) /= N_Defining_Operator_Symbol then
7549 Typ := Base_Type (Etype (First_Formal (Subp)));
7551 -- Check explicitly that the operation is a primitive of the type
7553 return Operator_Matches_Spec (Subp, Subp)
7554 and then not Is_Generic_Type (Typ)
7555 and then Scope (Subp) = Scope (Typ)
7556 and then not Is_Class_Wide_Type (Typ);
7558 end Can_Override_Operator;
7560 ----------------------
7561 -- Conforming_Types --
7562 ----------------------
7564 function Conforming_Types
7567 Ctype : Conformance_Type;
7568 Get_Inst : Boolean := False) return Boolean
7570 Type_1 : Entity_Id := T1;
7571 Type_2 : Entity_Id := T2;
7572 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
7574 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
7575 -- If neither T1 nor T2 are generic actual types, or if they are in
7576 -- different scopes (e.g. parent and child instances), then verify that
7577 -- the base types are equal. Otherwise T1 and T2 must be on the same
7578 -- subtype chain. The whole purpose of this procedure is to prevent
7579 -- spurious ambiguities in an instantiation that may arise if two
7580 -- distinct generic types are instantiated with the same actual.
7582 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
7583 -- An access parameter can designate an incomplete type. If the
7584 -- incomplete type is the limited view of a type from a limited_
7585 -- with_clause, check whether the non-limited view is available. If
7586 -- it is a (non-limited) incomplete type, get the full view.
7588 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
7589 -- Returns True if and only if either T1 denotes a limited view of T2
7590 -- or T2 denotes a limited view of T1. This can arise when the limited
7591 -- with view of a type is used in a subprogram declaration and the
7592 -- subprogram body is in the scope of a regular with clause for the
7593 -- same unit. In such a case, the two type entities can be considered
7594 -- identical for purposes of conformance checking.
7596 ----------------------
7597 -- Base_Types_Match --
7598 ----------------------
7600 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
7601 BT1 : constant Entity_Id := Base_Type (T1);
7602 BT2 : constant Entity_Id := Base_Type (T2);
7608 elsif BT1 = BT2 then
7610 -- The following is too permissive. A more precise test should
7611 -- check that the generic actual is an ancestor subtype of the
7614 -- See code in Find_Corresponding_Spec that applies an additional
7615 -- filter to handle accidental amiguities in instances.
7617 return not Is_Generic_Actual_Type (T1)
7618 or else not Is_Generic_Actual_Type (T2)
7619 or else Scope (T1) /= Scope (T2);
7621 -- If T2 is a generic actual type it is declared as the subtype of
7622 -- the actual. If that actual is itself a subtype we need to use its
7623 -- own base type to check for compatibility.
7625 elsif Ekind (BT2) = Ekind (T2) and then BT1 = Base_Type (BT2) then
7628 elsif Ekind (BT1) = Ekind (T1) and then BT2 = Base_Type (BT1) then
7634 end Base_Types_Match;
7636 --------------------------
7637 -- Find_Designated_Type --
7638 --------------------------
7640 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
7644 Desig := Directly_Designated_Type (T);
7646 if Ekind (Desig) = E_Incomplete_Type then
7648 -- If regular incomplete type, get full view if available
7650 if Present (Full_View (Desig)) then
7651 Desig := Full_View (Desig);
7653 -- If limited view of a type, get non-limited view if available,
7654 -- and check again for a regular incomplete type.
7656 elsif Present (Non_Limited_View (Desig)) then
7657 Desig := Get_Full_View (Non_Limited_View (Desig));
7662 end Find_Designated_Type;
7664 -------------------------------
7665 -- Matches_Limited_With_View --
7666 -------------------------------
7668 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
7670 -- In some cases a type imported through a limited_with clause, and
7671 -- its nonlimited view are both visible, for example in an anonymous
7672 -- access-to-class-wide type in a formal. Both entities designate the
7675 if From_With_Type (T1) and then T2 = Available_View (T1) then
7678 elsif From_With_Type (T2) and then T1 = Available_View (T2) then
7681 elsif From_With_Type (T1)
7682 and then From_With_Type (T2)
7683 and then Available_View (T1) = Available_View (T2)
7690 end Matches_Limited_With_View;
7692 -- Start of processing for Conforming_Types
7695 -- The context is an instance association for a formal access-to-
7696 -- subprogram type; the formal parameter types require mapping because
7697 -- they may denote other formal parameters of the generic unit.
7700 Type_1 := Get_Instance_Of (T1);
7701 Type_2 := Get_Instance_Of (T2);
7704 -- If one of the types is a view of the other introduced by a limited
7705 -- with clause, treat these as conforming for all purposes.
7707 if Matches_Limited_With_View (T1, T2) then
7710 elsif Base_Types_Match (Type_1, Type_2) then
7711 return Ctype <= Mode_Conformant
7712 or else Subtypes_Statically_Match (Type_1, Type_2);
7714 elsif Is_Incomplete_Or_Private_Type (Type_1)
7715 and then Present (Full_View (Type_1))
7716 and then Base_Types_Match (Full_View (Type_1), Type_2)
7718 return Ctype <= Mode_Conformant
7719 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
7721 elsif Ekind (Type_2) = E_Incomplete_Type
7722 and then Present (Full_View (Type_2))
7723 and then Base_Types_Match (Type_1, Full_View (Type_2))
7725 return Ctype <= Mode_Conformant
7726 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7728 elsif Is_Private_Type (Type_2)
7729 and then In_Instance
7730 and then Present (Full_View (Type_2))
7731 and then Base_Types_Match (Type_1, Full_View (Type_2))
7733 return Ctype <= Mode_Conformant
7734 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
7737 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
7738 -- treated recursively because they carry a signature. As far as
7739 -- conformance is concerned, convention plays no role, and either
7740 -- or both could be access to protected subprograms.
7742 Are_Anonymous_Access_To_Subprogram_Types :=
7743 Ekind_In (Type_1, E_Anonymous_Access_Subprogram_Type,
7744 E_Anonymous_Access_Protected_Subprogram_Type)
7746 Ekind_In (Type_2, E_Anonymous_Access_Subprogram_Type,
7747 E_Anonymous_Access_Protected_Subprogram_Type);
7749 -- Test anonymous access type case. For this case, static subtype
7750 -- matching is required for mode conformance (RM 6.3.1(15)). We check
7751 -- the base types because we may have built internal subtype entities
7752 -- to handle null-excluding types (see Process_Formals).
7754 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
7756 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
7758 -- Ada 2005 (AI-254)
7760 or else Are_Anonymous_Access_To_Subprogram_Types
7763 Desig_1 : Entity_Id;
7764 Desig_2 : Entity_Id;
7767 -- In Ada 2005, access constant indicators must match for
7768 -- subtype conformance.
7770 if Ada_Version >= Ada_2005
7771 and then Ctype >= Subtype_Conformant
7773 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
7778 Desig_1 := Find_Designated_Type (Type_1);
7779 Desig_2 := Find_Designated_Type (Type_2);
7781 -- If the context is an instance association for a formal
7782 -- access-to-subprogram type; formal access parameter designated
7783 -- types require mapping because they may denote other formal
7784 -- parameters of the generic unit.
7787 Desig_1 := Get_Instance_Of (Desig_1);
7788 Desig_2 := Get_Instance_Of (Desig_2);
7791 -- It is possible for a Class_Wide_Type to be introduced for an
7792 -- incomplete type, in which case there is a separate class_ wide
7793 -- type for the full view. The types conform if their Etypes
7794 -- conform, i.e. one may be the full view of the other. This can
7795 -- only happen in the context of an access parameter, other uses
7796 -- of an incomplete Class_Wide_Type are illegal.
7798 if Is_Class_Wide_Type (Desig_1)
7800 Is_Class_Wide_Type (Desig_2)
7804 (Etype (Base_Type (Desig_1)),
7805 Etype (Base_Type (Desig_2)), Ctype);
7807 elsif Are_Anonymous_Access_To_Subprogram_Types then
7808 if Ada_Version < Ada_2005 then
7809 return Ctype = Type_Conformant
7811 Subtypes_Statically_Match (Desig_1, Desig_2);
7813 -- We must check the conformance of the signatures themselves
7817 Conformant : Boolean;
7820 (Desig_1, Desig_2, Ctype, False, Conformant);
7826 return Base_Type (Desig_1) = Base_Type (Desig_2)
7827 and then (Ctype = Type_Conformant
7829 Subtypes_Statically_Match (Desig_1, Desig_2));
7833 -- Otherwise definitely no match
7836 if ((Ekind (Type_1) = E_Anonymous_Access_Type
7837 and then Is_Access_Type (Type_2))
7838 or else (Ekind (Type_2) = E_Anonymous_Access_Type
7839 and then Is_Access_Type (Type_1)))
7842 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
7844 May_Hide_Profile := True;
7849 end Conforming_Types;
7851 --------------------------
7852 -- Create_Extra_Formals --
7853 --------------------------
7855 procedure Create_Extra_Formals (E : Entity_Id) is
7857 First_Extra : Entity_Id := Empty;
7858 Last_Extra : Entity_Id;
7859 Formal_Type : Entity_Id;
7860 P_Formal : Entity_Id := Empty;
7862 function Add_Extra_Formal
7863 (Assoc_Entity : Entity_Id;
7866 Suffix : String) return Entity_Id;
7867 -- Add an extra formal to the current list of formals and extra formals.
7868 -- The extra formal is added to the end of the list of extra formals,
7869 -- and also returned as the result. These formals are always of mode IN.
7870 -- The new formal has the type Typ, is declared in Scope, and its name
7871 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
7872 -- The following suffixes are currently used. They should not be changed
7873 -- without coordinating with CodePeer, which makes use of these to
7874 -- provide better messages.
7876 -- O denotes the Constrained bit.
7877 -- L denotes the accessibility level.
7878 -- BIP_xxx denotes an extra formal for a build-in-place function. See
7879 -- the full list in exp_ch6.BIP_Formal_Kind.
7881 ----------------------
7882 -- Add_Extra_Formal --
7883 ----------------------
7885 function Add_Extra_Formal
7886 (Assoc_Entity : Entity_Id;
7889 Suffix : String) return Entity_Id
7891 EF : constant Entity_Id :=
7892 Make_Defining_Identifier (Sloc (Assoc_Entity),
7893 Chars => New_External_Name (Chars (Assoc_Entity),
7897 -- A little optimization. Never generate an extra formal for the
7898 -- _init operand of an initialization procedure, since it could
7901 if Chars (Formal) = Name_uInit then
7905 Set_Ekind (EF, E_In_Parameter);
7906 Set_Actual_Subtype (EF, Typ);
7907 Set_Etype (EF, Typ);
7908 Set_Scope (EF, Scope);
7909 Set_Mechanism (EF, Default_Mechanism);
7910 Set_Formal_Validity (EF);
7912 if No (First_Extra) then
7914 Set_Extra_Formals (Scope, First_Extra);
7917 if Present (Last_Extra) then
7918 Set_Extra_Formal (Last_Extra, EF);
7924 end Add_Extra_Formal;
7926 -- Start of processing for Create_Extra_Formals
7929 -- We never generate extra formals if expansion is not active because we
7930 -- don't need them unless we are generating code.
7932 if not Expander_Active then
7936 -- No need to generate extra formals in interface thunks whose target
7937 -- primitive has no extra formals.
7939 if Is_Thunk (E) and then No (Extra_Formals (Thunk_Entity (E))) then
7943 -- If this is a derived subprogram then the subtypes of the parent
7944 -- subprogram's formal parameters will be used to determine the need
7945 -- for extra formals.
7947 if Is_Overloadable (E) and then Present (Alias (E)) then
7948 P_Formal := First_Formal (Alias (E));
7951 Last_Extra := Empty;
7952 Formal := First_Formal (E);
7953 while Present (Formal) loop
7954 Last_Extra := Formal;
7955 Next_Formal (Formal);
7958 -- If Extra_formals were already created, don't do it again. This
7959 -- situation may arise for subprogram types created as part of
7960 -- dispatching calls (see Expand_Dispatching_Call)
7962 if Present (Last_Extra) and then Present (Extra_Formal (Last_Extra)) then
7966 -- If the subprogram is a predefined dispatching subprogram then don't
7967 -- generate any extra constrained or accessibility level formals. In
7968 -- general we suppress these for internal subprograms (by not calling
7969 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
7970 -- generated stream attributes do get passed through because extra
7971 -- build-in-place formals are needed in some cases (limited 'Input).
7973 if Is_Predefined_Internal_Operation (E) then
7974 goto Test_For_Func_Result_Extras;
7977 Formal := First_Formal (E);
7978 while Present (Formal) loop
7980 -- Create extra formal for supporting the attribute 'Constrained.
7981 -- The case of a private type view without discriminants also
7982 -- requires the extra formal if the underlying type has defaulted
7985 if Ekind (Formal) /= E_In_Parameter then
7986 if Present (P_Formal) then
7987 Formal_Type := Etype (P_Formal);
7989 Formal_Type := Etype (Formal);
7992 -- Do not produce extra formals for Unchecked_Union parameters.
7993 -- Jump directly to the end of the loop.
7995 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
7996 goto Skip_Extra_Formal_Generation;
7999 if not Has_Discriminants (Formal_Type)
8000 and then Ekind (Formal_Type) in Private_Kind
8001 and then Present (Underlying_Type (Formal_Type))
8003 Formal_Type := Underlying_Type (Formal_Type);
8006 -- Suppress the extra formal if formal's subtype is constrained or
8007 -- indefinite, or we're compiling for Ada 2012 and the underlying
8008 -- type is tagged and limited. In Ada 2012, a limited tagged type
8009 -- can have defaulted discriminants, but 'Constrained is required
8010 -- to return True, so the formal is never needed (see AI05-0214).
8011 -- Note that this ensures consistency of calling sequences for
8012 -- dispatching operations when some types in a class have defaults
8013 -- on discriminants and others do not (and requiring the extra
8014 -- formal would introduce distributed overhead).
8016 -- If the type does not have a completion yet, treat as prior to
8017 -- Ada 2012 for consistency.
8019 if Has_Discriminants (Formal_Type)
8020 and then not Is_Constrained (Formal_Type)
8021 and then not Is_Indefinite_Subtype (Formal_Type)
8022 and then (Ada_Version < Ada_2012
8023 or else No (Underlying_Type (Formal_Type))
8025 (Is_Limited_Type (Formal_Type)
8028 (Underlying_Type (Formal_Type)))))
8030 Set_Extra_Constrained
8031 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
8035 -- Create extra formal for supporting accessibility checking. This
8036 -- is done for both anonymous access formals and formals of named
8037 -- access types that are marked as controlling formals. The latter
8038 -- case can occur when Expand_Dispatching_Call creates a subprogram
8039 -- type and substitutes the types of access-to-class-wide actuals
8040 -- for the anonymous access-to-specific-type of controlling formals.
8041 -- Base_Type is applied because in cases where there is a null
8042 -- exclusion the formal may have an access subtype.
8044 -- This is suppressed if we specifically suppress accessibility
8045 -- checks at the package level for either the subprogram, or the
8046 -- package in which it resides. However, we do not suppress it
8047 -- simply if the scope has accessibility checks suppressed, since
8048 -- this could cause trouble when clients are compiled with a
8049 -- different suppression setting. The explicit checks at the
8050 -- package level are safe from this point of view.
8052 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
8053 or else (Is_Controlling_Formal (Formal)
8054 and then Is_Access_Type (Base_Type (Etype (Formal)))))
8056 (Explicit_Suppress (E, Accessibility_Check)
8058 Explicit_Suppress (Scope (E), Accessibility_Check))
8061 or else Present (Extra_Accessibility (P_Formal)))
8063 Set_Extra_Accessibility
8064 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
8067 -- This label is required when skipping extra formal generation for
8068 -- Unchecked_Union parameters.
8070 <<Skip_Extra_Formal_Generation>>
8072 if Present (P_Formal) then
8073 Next_Formal (P_Formal);
8076 Next_Formal (Formal);
8079 <<Test_For_Func_Result_Extras>>
8081 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
8082 -- function call is ... determined by the point of call ...".
8084 if Needs_Result_Accessibility_Level (E) then
8085 Set_Extra_Accessibility_Of_Result
8086 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
8089 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
8090 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
8092 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
8094 Result_Subt : constant Entity_Id := Etype (E);
8095 Full_Subt : constant Entity_Id := Available_View (Result_Subt);
8096 Formal_Typ : Entity_Id;
8098 Discard : Entity_Id;
8099 pragma Warnings (Off, Discard);
8102 -- In the case of functions with unconstrained result subtypes,
8103 -- add a 4-state formal indicating whether the return object is
8104 -- allocated by the caller (1), or should be allocated by the
8105 -- callee on the secondary stack (2), in the global heap (3), or
8106 -- in a user-defined storage pool (4). For the moment we just use
8107 -- Natural for the type of this formal. Note that this formal
8108 -- isn't usually needed in the case where the result subtype is
8109 -- constrained, but it is needed when the function has a tagged
8110 -- result, because generally such functions can be called in a
8111 -- dispatching context and such calls must be handled like calls
8112 -- to a class-wide function.
8114 if Needs_BIP_Alloc_Form (E) then
8117 (E, Standard_Natural,
8118 E, BIP_Formal_Suffix (BIP_Alloc_Form));
8120 -- Add BIP_Storage_Pool, in case BIP_Alloc_Form indicates to
8121 -- use a user-defined pool. This formal is not added on
8122 -- .NET/JVM/ZFP as those targets do not support pools.
8124 if VM_Target = No_VM
8125 and then RTE_Available (RE_Root_Storage_Pool_Ptr)
8129 (E, RTE (RE_Root_Storage_Pool_Ptr),
8130 E, BIP_Formal_Suffix (BIP_Storage_Pool));
8134 -- In the case of functions whose result type needs finalization,
8135 -- add an extra formal which represents the finalization master.
8137 if Needs_BIP_Finalization_Master (E) then
8140 (E, RTE (RE_Finalization_Master_Ptr),
8141 E, BIP_Formal_Suffix (BIP_Finalization_Master));
8144 -- When the result type contains tasks, add two extra formals: the
8145 -- master of the tasks to be created, and the caller's activation
8148 if Has_Task (Full_Subt) then
8151 (E, RTE (RE_Master_Id),
8152 E, BIP_Formal_Suffix (BIP_Task_Master));
8155 (E, RTE (RE_Activation_Chain_Access),
8156 E, BIP_Formal_Suffix (BIP_Activation_Chain));
8159 -- All build-in-place functions get an extra formal that will be
8160 -- passed the address of the return object within the caller.
8163 Create_Itype (E_Anonymous_Access_Type, E, Scope_Id => Scope (E));
8165 Set_Directly_Designated_Type (Formal_Typ, Result_Subt);
8166 Set_Etype (Formal_Typ, Formal_Typ);
8167 Set_Depends_On_Private
8168 (Formal_Typ, Has_Private_Component (Formal_Typ));
8169 Set_Is_Public (Formal_Typ, Is_Public (Scope (Formal_Typ)));
8170 Set_Is_Access_Constant (Formal_Typ, False);
8172 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
8173 -- the designated type comes from the limited view (for back-end
8176 Set_From_With_Type (Formal_Typ, From_With_Type (Result_Subt));
8178 Layout_Type (Formal_Typ);
8182 (E, Formal_Typ, E, BIP_Formal_Suffix (BIP_Object_Access));
8185 end Create_Extra_Formals;
8187 -----------------------------
8188 -- Enter_Overloaded_Entity --
8189 -----------------------------
8191 procedure Enter_Overloaded_Entity (S : Entity_Id) is
8192 E : Entity_Id := Current_Entity_In_Scope (S);
8193 C_E : Entity_Id := Current_Entity (S);
8197 Set_Has_Homonym (E);
8198 Set_Has_Homonym (S);
8201 Set_Is_Immediately_Visible (S);
8202 Set_Scope (S, Current_Scope);
8204 -- Chain new entity if front of homonym in current scope, so that
8205 -- homonyms are contiguous.
8207 if Present (E) and then E /= C_E then
8208 while Homonym (C_E) /= E loop
8209 C_E := Homonym (C_E);
8212 Set_Homonym (C_E, S);
8216 Set_Current_Entity (S);
8221 if Is_Inherited_Operation (S) then
8222 Append_Inherited_Subprogram (S);
8224 Append_Entity (S, Current_Scope);
8227 Set_Public_Status (S);
8229 if Debug_Flag_E then
8230 Write_Str ("New overloaded entity chain: ");
8231 Write_Name (Chars (S));
8234 while Present (E) loop
8235 Write_Str (" "); Write_Int (Int (E));
8242 -- Generate warning for hiding
8245 and then Comes_From_Source (S)
8246 and then In_Extended_Main_Source_Unit (S)
8253 -- Warn unless genuine overloading. Do not emit warning on
8254 -- hiding predefined operators in Standard (these are either an
8255 -- (artifact of our implicit declarations, or simple noise) but
8256 -- keep warning on a operator defined on a local subtype, because
8257 -- of the real danger that different operators may be applied in
8258 -- various parts of the program.
8260 -- Note that if E and S have the same scope, there is never any
8261 -- hiding. Either the two conflict, and the program is illegal,
8262 -- or S is overriding an implicit inherited subprogram.
8264 if Scope (E) /= Scope (S)
8265 and then (not Is_Overloadable (E)
8266 or else Subtype_Conformant (E, S))
8267 and then (Is_Immediately_Visible (E)
8269 Is_Potentially_Use_Visible (S))
8271 if Scope (E) /= Standard_Standard then
8272 Error_Msg_Sloc := Sloc (E);
8273 Error_Msg_N ("declaration of & hides one#?h?", S);
8275 elsif Nkind (S) = N_Defining_Operator_Symbol
8277 Scope (Base_Type (Etype (First_Formal (S)))) /= Scope (S)
8280 ("declaration of & hides predefined operator?h?", S);
8285 end Enter_Overloaded_Entity;
8287 -----------------------------
8288 -- Check_Untagged_Equality --
8289 -----------------------------
8291 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
8292 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
8293 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
8297 if Nkind (Decl) = N_Subprogram_Declaration
8298 and then Is_Record_Type (Typ)
8299 and then not Is_Tagged_Type (Typ)
8301 -- If the type is not declared in a package, or if we are in the
8302 -- body of the package or in some other scope, the new operation is
8303 -- not primitive, and therefore legal, though suspicious. If the
8304 -- type is a generic actual (sub)type, the operation is not primitive
8305 -- either because the base type is declared elsewhere.
8307 if Is_Frozen (Typ) then
8308 if Ekind (Scope (Typ)) /= E_Package
8309 or else Scope (Typ) /= Current_Scope
8313 elsif Is_Generic_Actual_Type (Typ) then
8316 elsif In_Package_Body (Scope (Typ)) then
8318 ("equality operator must be declared "
8319 & "before type& is frozen", Eq_Op, Typ);
8321 ("\move declaration to package spec", Eq_Op);
8325 ("equality operator must be declared "
8326 & "before type& is frozen", Eq_Op, Typ);
8328 Obj_Decl := Next (Parent (Typ));
8329 while Present (Obj_Decl) and then Obj_Decl /= Decl loop
8330 if Nkind (Obj_Decl) = N_Object_Declaration
8331 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
8334 ("type& is frozen by declaration??", Obj_Decl, Typ);
8336 ("\an equality operator cannot be declared after this "
8337 & "point (RM 4.5.2 (9.8)) (Ada 2012))??", Obj_Decl);
8345 elsif not In_Same_List (Parent (Typ), Decl)
8346 and then not Is_Limited_Type (Typ)
8349 -- This makes it illegal to have a primitive equality declared in
8350 -- the private part if the type is visible.
8352 Error_Msg_N ("equality operator appears too late", Eq_Op);
8355 end Check_Untagged_Equality;
8357 -----------------------------
8358 -- Find_Corresponding_Spec --
8359 -----------------------------
8361 function Find_Corresponding_Spec
8363 Post_Error : Boolean := True) return Entity_Id
8365 Spec : constant Node_Id := Specification (N);
8366 Designator : constant Entity_Id := Defining_Entity (Spec);
8370 function Different_Generic_Profile (E : Entity_Id) return Boolean;
8371 -- Even if fully conformant, a body may depend on a generic actual when
8372 -- the spec does not, or vice versa, in which case they were distinct
8373 -- entities in the generic.
8375 -------------------------------
8376 -- Different_Generic_Profile --
8377 -------------------------------
8379 function Different_Generic_Profile (E : Entity_Id) return Boolean is
8382 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean;
8383 -- Check that the types of corresponding formals have the same
8384 -- generic actual if any. We have to account for subtypes of a
8385 -- generic formal, declared between a spec and a body, which may
8386 -- appear distinct in an instance but matched in the generic.
8388 -------------------------
8389 -- Same_Generic_Actual --
8390 -------------------------
8392 function Same_Generic_Actual (T1, T2 : Entity_Id) return Boolean is
8394 return Is_Generic_Actual_Type (T1) = Is_Generic_Actual_Type (T2)
8396 (Present (Parent (T1))
8397 and then Comes_From_Source (Parent (T1))
8398 and then Nkind (Parent (T1)) = N_Subtype_Declaration
8399 and then Is_Entity_Name (Subtype_Indication (Parent (T1)))
8400 and then Entity (Subtype_Indication (Parent (T1))) = T2);
8401 end Same_Generic_Actual;
8403 -- Start of processing for Different_Generic_Profile
8406 if not In_Instance then
8409 elsif Ekind (E) = E_Function
8410 and then not Same_Generic_Actual (Etype (E), Etype (Designator))
8415 F1 := First_Formal (Designator);
8416 F2 := First_Formal (E);
8417 while Present (F1) loop
8418 if not Same_Generic_Actual (Etype (F1), Etype (F2)) then
8427 end Different_Generic_Profile;
8429 -- Start of processing for Find_Corresponding_Spec
8432 E := Current_Entity (Designator);
8433 while Present (E) loop
8435 -- We are looking for a matching spec. It must have the same scope,
8436 -- and the same name, and either be type conformant, or be the case
8437 -- of a library procedure spec and its body (which belong to one
8438 -- another regardless of whether they are type conformant or not).
8440 if Scope (E) = Current_Scope then
8441 if Current_Scope = Standard_Standard
8442 or else (Ekind (E) = Ekind (Designator)
8443 and then Type_Conformant (E, Designator))
8445 -- Within an instantiation, we know that spec and body are
8446 -- subtype conformant, because they were subtype conformant in
8447 -- the generic. We choose the subtype-conformant entity here as
8448 -- well, to resolve spurious ambiguities in the instance that
8449 -- were not present in the generic (i.e. when two different
8450 -- types are given the same actual). If we are looking for a
8451 -- spec to match a body, full conformance is expected.
8454 Set_Convention (Designator, Convention (E));
8456 -- Skip past subprogram bodies and subprogram renamings that
8457 -- may appear to have a matching spec, but that aren't fully
8458 -- conformant with it. That can occur in cases where an
8459 -- actual type causes unrelated homographs in the instance.
8461 if Nkind_In (N, N_Subprogram_Body,
8462 N_Subprogram_Renaming_Declaration)
8463 and then Present (Homonym (E))
8464 and then not Fully_Conformant (Designator, E)
8468 elsif not Subtype_Conformant (Designator, E) then
8471 elsif Different_Generic_Profile (E) then
8476 -- Ada 2012 (AI05-0165): For internally generated bodies of
8477 -- null procedures locate the internally generated spec. We
8478 -- enforce mode conformance since a tagged type may inherit
8479 -- from interfaces several null primitives which differ only
8480 -- in the mode of the formals.
8482 if not (Comes_From_Source (E))
8483 and then Is_Null_Procedure (E)
8484 and then not Mode_Conformant (Designator, E)
8488 -- For null procedures coming from source that are completions,
8489 -- analysis of the generated body will establish the link.
8491 elsif Comes_From_Source (E)
8492 and then Nkind (Spec) = N_Procedure_Specification
8493 and then Null_Present (Spec)
8497 elsif not Has_Completion (E) then
8498 if Nkind (N) /= N_Subprogram_Body_Stub then
8499 Set_Corresponding_Spec (N, E);
8502 Set_Has_Completion (E);
8505 elsif Nkind (Parent (N)) = N_Subunit then
8507 -- If this is the proper body of a subunit, the completion
8508 -- flag is set when analyzing the stub.
8512 -- If E is an internal function with a controlling result that
8513 -- was created for an operation inherited by a null extension,
8514 -- it may be overridden by a body without a previous spec (one
8515 -- more reason why these should be shunned). In that case we
8516 -- remove the generated body if present, because the current
8517 -- one is the explicit overriding.
8519 elsif Ekind (E) = E_Function
8520 and then Ada_Version >= Ada_2005
8521 and then not Comes_From_Source (E)
8522 and then Has_Controlling_Result (E)
8523 and then Is_Null_Extension (Etype (E))
8524 and then Comes_From_Source (Spec)
8526 Set_Has_Completion (E, False);
8529 and then Nkind (Parent (E)) = N_Function_Specification
8532 (Unit_Declaration_Node
8533 (Corresponding_Body (Unit_Declaration_Node (E))));
8537 -- If expansion is disabled, or if the wrapper function has
8538 -- not been generated yet, this a late body overriding an
8539 -- inherited operation, or it is an overriding by some other
8540 -- declaration before the controlling result is frozen. In
8541 -- either case this is a declaration of a new entity.
8547 -- If the body already exists, then this is an error unless
8548 -- the previous declaration is the implicit declaration of a
8549 -- derived subprogram. It is also legal for an instance to
8550 -- contain type conformant overloadable declarations (but the
8551 -- generic declaration may not), per 8.3(26/2).
8553 elsif No (Alias (E))
8554 and then not Is_Intrinsic_Subprogram (E)
8555 and then not In_Instance
8558 Error_Msg_Sloc := Sloc (E);
8560 if Is_Imported (E) then
8562 ("body not allowed for imported subprogram & declared#",
8565 Error_Msg_NE ("duplicate body for & declared#", N, E);
8569 -- Child units cannot be overloaded, so a conformance mismatch
8570 -- between body and a previous spec is an error.
8572 elsif Is_Child_Unit (E)
8574 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
8576 Nkind (Parent (Unit_Declaration_Node (Designator))) =
8581 ("body of child unit does not match previous declaration", N);
8589 -- On exit, we know that no previous declaration of subprogram exists
8592 end Find_Corresponding_Spec;
8594 ----------------------
8595 -- Fully_Conformant --
8596 ----------------------
8598 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
8601 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
8603 end Fully_Conformant;
8605 ----------------------------------
8606 -- Fully_Conformant_Expressions --
8607 ----------------------------------
8609 function Fully_Conformant_Expressions
8610 (Given_E1 : Node_Id;
8611 Given_E2 : Node_Id) return Boolean
8613 E1 : constant Node_Id := Original_Node (Given_E1);
8614 E2 : constant Node_Id := Original_Node (Given_E2);
8615 -- We always test conformance on original nodes, since it is possible
8616 -- for analysis and/or expansion to make things look as though they
8617 -- conform when they do not, e.g. by converting 1+2 into 3.
8619 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
8620 renames Fully_Conformant_Expressions;
8622 function FCL (L1, L2 : List_Id) return Boolean;
8623 -- Compare elements of two lists for conformance. Elements have to be
8624 -- conformant, and actuals inserted as default parameters do not match
8625 -- explicit actuals with the same value.
8627 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
8628 -- Compare an operator node with a function call
8634 function FCL (L1, L2 : List_Id) return Boolean is
8638 if L1 = No_List then
8644 if L2 = No_List then
8650 -- Compare two lists, skipping rewrite insertions (we want to compare
8651 -- the original trees, not the expanded versions!)
8654 if Is_Rewrite_Insertion (N1) then
8656 elsif Is_Rewrite_Insertion (N2) then
8662 elsif not FCE (N1, N2) then
8675 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
8676 Actuals : constant List_Id := Parameter_Associations (Call_Node);
8681 or else Entity (Op_Node) /= Entity (Name (Call_Node))
8686 Act := First (Actuals);
8688 if Nkind (Op_Node) in N_Binary_Op then
8689 if not FCE (Left_Opnd (Op_Node), Act) then
8696 return Present (Act)
8697 and then FCE (Right_Opnd (Op_Node), Act)
8698 and then No (Next (Act));
8702 -- Start of processing for Fully_Conformant_Expressions
8705 -- Non-conformant if paren count does not match. Note: if some idiot
8706 -- complains that we don't do this right for more than 3 levels of
8707 -- parentheses, they will be treated with the respect they deserve!
8709 if Paren_Count (E1) /= Paren_Count (E2) then
8712 -- If same entities are referenced, then they are conformant even if
8713 -- they have different forms (RM 8.3.1(19-20)).
8715 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
8716 if Present (Entity (E1)) then
8717 return Entity (E1) = Entity (E2)
8718 or else (Chars (Entity (E1)) = Chars (Entity (E2))
8719 and then Ekind (Entity (E1)) = E_Discriminant
8720 and then Ekind (Entity (E2)) = E_In_Parameter);
8722 elsif Nkind (E1) = N_Expanded_Name
8723 and then Nkind (E2) = N_Expanded_Name
8724 and then Nkind (Selector_Name (E1)) = N_Character_Literal
8725 and then Nkind (Selector_Name (E2)) = N_Character_Literal
8727 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
8730 -- Identifiers in component associations don't always have
8731 -- entities, but their names must conform.
8733 return Nkind (E1) = N_Identifier
8734 and then Nkind (E2) = N_Identifier
8735 and then Chars (E1) = Chars (E2);
8738 elsif Nkind (E1) = N_Character_Literal
8739 and then Nkind (E2) = N_Expanded_Name
8741 return Nkind (Selector_Name (E2)) = N_Character_Literal
8742 and then Chars (E1) = Chars (Selector_Name (E2));
8744 elsif Nkind (E2) = N_Character_Literal
8745 and then Nkind (E1) = N_Expanded_Name
8747 return Nkind (Selector_Name (E1)) = N_Character_Literal
8748 and then Chars (E2) = Chars (Selector_Name (E1));
8750 elsif Nkind (E1) in N_Op and then Nkind (E2) = N_Function_Call then
8751 return FCO (E1, E2);
8753 elsif Nkind (E2) in N_Op and then Nkind (E1) = N_Function_Call then
8754 return FCO (E2, E1);
8756 -- Otherwise we must have the same syntactic entity
8758 elsif Nkind (E1) /= Nkind (E2) then
8761 -- At this point, we specialize by node type
8768 FCL (Expressions (E1), Expressions (E2))
8770 FCL (Component_Associations (E1),
8771 Component_Associations (E2));
8774 if Nkind (Expression (E1)) = N_Qualified_Expression
8776 Nkind (Expression (E2)) = N_Qualified_Expression
8778 return FCE (Expression (E1), Expression (E2));
8780 -- Check that the subtype marks and any constraints
8785 Indic1 : constant Node_Id := Expression (E1);
8786 Indic2 : constant Node_Id := Expression (E2);
8791 if Nkind (Indic1) /= N_Subtype_Indication then
8793 Nkind (Indic2) /= N_Subtype_Indication
8794 and then Entity (Indic1) = Entity (Indic2);
8796 elsif Nkind (Indic2) /= N_Subtype_Indication then
8798 Nkind (Indic1) /= N_Subtype_Indication
8799 and then Entity (Indic1) = Entity (Indic2);
8802 if Entity (Subtype_Mark (Indic1)) /=
8803 Entity (Subtype_Mark (Indic2))
8808 Elt1 := First (Constraints (Constraint (Indic1)));
8809 Elt2 := First (Constraints (Constraint (Indic2)));
8810 while Present (Elt1) and then Present (Elt2) loop
8811 if not FCE (Elt1, Elt2) then
8824 when N_Attribute_Reference =>
8826 Attribute_Name (E1) = Attribute_Name (E2)
8827 and then FCL (Expressions (E1), Expressions (E2));
8831 Entity (E1) = Entity (E2)
8832 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
8833 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
8835 when N_Short_Circuit | N_Membership_Test =>
8837 FCE (Left_Opnd (E1), Left_Opnd (E2))
8839 FCE (Right_Opnd (E1), Right_Opnd (E2));
8841 when N_Case_Expression =>
8847 if not FCE (Expression (E1), Expression (E2)) then
8851 Alt1 := First (Alternatives (E1));
8852 Alt2 := First (Alternatives (E2));
8854 if Present (Alt1) /= Present (Alt2) then
8856 elsif No (Alt1) then
8860 if not FCE (Expression (Alt1), Expression (Alt2))
8861 or else not FCL (Discrete_Choices (Alt1),
8862 Discrete_Choices (Alt2))
8873 when N_Character_Literal =>
8875 Char_Literal_Value (E1) = Char_Literal_Value (E2);
8877 when N_Component_Association =>
8879 FCL (Choices (E1), Choices (E2))
8881 FCE (Expression (E1), Expression (E2));
8883 when N_Explicit_Dereference =>
8885 FCE (Prefix (E1), Prefix (E2));
8887 when N_Extension_Aggregate =>
8889 FCL (Expressions (E1), Expressions (E2))
8890 and then Null_Record_Present (E1) =
8891 Null_Record_Present (E2)
8892 and then FCL (Component_Associations (E1),
8893 Component_Associations (E2));
8895 when N_Function_Call =>
8897 FCE (Name (E1), Name (E2))
8899 FCL (Parameter_Associations (E1),
8900 Parameter_Associations (E2));
8902 when N_If_Expression =>
8904 FCL (Expressions (E1), Expressions (E2));
8906 when N_Indexed_Component =>
8908 FCE (Prefix (E1), Prefix (E2))
8910 FCL (Expressions (E1), Expressions (E2));
8912 when N_Integer_Literal =>
8913 return (Intval (E1) = Intval (E2));
8918 when N_Operator_Symbol =>
8920 Chars (E1) = Chars (E2);
8922 when N_Others_Choice =>
8925 when N_Parameter_Association =>
8927 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
8928 and then FCE (Explicit_Actual_Parameter (E1),
8929 Explicit_Actual_Parameter (E2));
8931 when N_Qualified_Expression =>
8933 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
8935 FCE (Expression (E1), Expression (E2));
8937 when N_Quantified_Expression =>
8938 if not FCE (Condition (E1), Condition (E2)) then
8942 if Present (Loop_Parameter_Specification (E1))
8943 and then Present (Loop_Parameter_Specification (E2))
8946 L1 : constant Node_Id :=
8947 Loop_Parameter_Specification (E1);
8948 L2 : constant Node_Id :=
8949 Loop_Parameter_Specification (E2);
8953 Reverse_Present (L1) = Reverse_Present (L2)
8955 FCE (Defining_Identifier (L1),
8956 Defining_Identifier (L2))
8958 FCE (Discrete_Subtype_Definition (L1),
8959 Discrete_Subtype_Definition (L2));
8962 elsif Present (Iterator_Specification (E1))
8963 and then Present (Iterator_Specification (E2))
8966 I1 : constant Node_Id := Iterator_Specification (E1);
8967 I2 : constant Node_Id := Iterator_Specification (E2);
8971 FCE (Defining_Identifier (I1),
8972 Defining_Identifier (I2))
8974 Of_Present (I1) = Of_Present (I2)
8976 Reverse_Present (I1) = Reverse_Present (I2)
8977 and then FCE (Name (I1), Name (I2))
8978 and then FCE (Subtype_Indication (I1),
8979 Subtype_Indication (I2));
8982 -- The quantified expressions used different specifications to
8983 -- walk their respective ranges.
8991 FCE (Low_Bound (E1), Low_Bound (E2))
8993 FCE (High_Bound (E1), High_Bound (E2));
8995 when N_Real_Literal =>
8996 return (Realval (E1) = Realval (E2));
8998 when N_Selected_Component =>
9000 FCE (Prefix (E1), Prefix (E2))
9002 FCE (Selector_Name (E1), Selector_Name (E2));
9006 FCE (Prefix (E1), Prefix (E2))
9008 FCE (Discrete_Range (E1), Discrete_Range (E2));
9010 when N_String_Literal =>
9012 S1 : constant String_Id := Strval (E1);
9013 S2 : constant String_Id := Strval (E2);
9014 L1 : constant Nat := String_Length (S1);
9015 L2 : constant Nat := String_Length (S2);
9022 for J in 1 .. L1 loop
9023 if Get_String_Char (S1, J) /=
9024 Get_String_Char (S2, J)
9034 when N_Type_Conversion =>
9036 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9038 FCE (Expression (E1), Expression (E2));
9042 Entity (E1) = Entity (E2)
9044 FCE (Right_Opnd (E1), Right_Opnd (E2));
9046 when N_Unchecked_Type_Conversion =>
9048 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
9050 FCE (Expression (E1), Expression (E2));
9052 -- All other node types cannot appear in this context. Strictly
9053 -- we should raise a fatal internal error. Instead we just ignore
9054 -- the nodes. This means that if anyone makes a mistake in the
9055 -- expander and mucks an expression tree irretrievably, the result
9056 -- will be a failure to detect a (probably very obscure) case
9057 -- of non-conformance, which is better than bombing on some
9058 -- case where two expressions do in fact conform.
9065 end Fully_Conformant_Expressions;
9067 ----------------------------------------
9068 -- Fully_Conformant_Discrete_Subtypes --
9069 ----------------------------------------
9071 function Fully_Conformant_Discrete_Subtypes
9072 (Given_S1 : Node_Id;
9073 Given_S2 : Node_Id) return Boolean
9075 S1 : constant Node_Id := Original_Node (Given_S1);
9076 S2 : constant Node_Id := Original_Node (Given_S2);
9078 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
9079 -- Special-case for a bound given by a discriminant, which in the body
9080 -- is replaced with the discriminal of the enclosing type.
9082 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
9083 -- Check both bounds
9085 -----------------------
9086 -- Conforming_Bounds --
9087 -----------------------
9089 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
9091 if Is_Entity_Name (B1)
9092 and then Is_Entity_Name (B2)
9093 and then Ekind (Entity (B1)) = E_Discriminant
9095 return Chars (B1) = Chars (B2);
9098 return Fully_Conformant_Expressions (B1, B2);
9100 end Conforming_Bounds;
9102 -----------------------
9103 -- Conforming_Ranges --
9104 -----------------------
9106 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
9109 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
9111 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
9112 end Conforming_Ranges;
9114 -- Start of processing for Fully_Conformant_Discrete_Subtypes
9117 if Nkind (S1) /= Nkind (S2) then
9120 elsif Is_Entity_Name (S1) then
9121 return Entity (S1) = Entity (S2);
9123 elsif Nkind (S1) = N_Range then
9124 return Conforming_Ranges (S1, S2);
9126 elsif Nkind (S1) = N_Subtype_Indication then
9128 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
9131 (Range_Expression (Constraint (S1)),
9132 Range_Expression (Constraint (S2)));
9136 end Fully_Conformant_Discrete_Subtypes;
9138 --------------------
9139 -- Install_Entity --
9140 --------------------
9142 procedure Install_Entity (E : Entity_Id) is
9143 Prev : constant Entity_Id := Current_Entity (E);
9145 Set_Is_Immediately_Visible (E);
9146 Set_Current_Entity (E);
9147 Set_Homonym (E, Prev);
9150 ---------------------
9151 -- Install_Formals --
9152 ---------------------
9154 procedure Install_Formals (Id : Entity_Id) is
9157 F := First_Formal (Id);
9158 while Present (F) loop
9162 end Install_Formals;
9164 -----------------------------
9165 -- Is_Interface_Conformant --
9166 -----------------------------
9168 function Is_Interface_Conformant
9169 (Tagged_Type : Entity_Id;
9170 Iface_Prim : Entity_Id;
9171 Prim : Entity_Id) return Boolean
9173 -- The operation may in fact be an inherited (implicit) operation
9174 -- rather than the original interface primitive, so retrieve the
9175 -- ultimate ancestor.
9177 Iface : constant Entity_Id :=
9178 Find_Dispatching_Type (Ultimate_Alias (Iface_Prim));
9179 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
9181 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
9182 -- Return the controlling formal of Prim
9184 ------------------------
9185 -- Controlling_Formal --
9186 ------------------------
9188 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
9192 E := First_Entity (Prim);
9193 while Present (E) loop
9194 if Is_Formal (E) and then Is_Controlling_Formal (E) then
9202 end Controlling_Formal;
9206 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
9207 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
9209 -- Start of processing for Is_Interface_Conformant
9212 pragma Assert (Is_Subprogram (Iface_Prim)
9213 and then Is_Subprogram (Prim)
9214 and then Is_Dispatching_Operation (Iface_Prim)
9215 and then Is_Dispatching_Operation (Prim));
9217 pragma Assert (Is_Interface (Iface)
9218 or else (Present (Alias (Iface_Prim))
9221 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
9223 if Prim = Iface_Prim
9224 or else not Is_Subprogram (Prim)
9225 or else Ekind (Prim) /= Ekind (Iface_Prim)
9226 or else not Is_Dispatching_Operation (Prim)
9227 or else Scope (Prim) /= Scope (Tagged_Type)
9229 or else Base_Type (Typ) /= Base_Type (Tagged_Type)
9230 or else not Primitive_Names_Match (Iface_Prim, Prim)
9234 -- The mode of the controlling formals must match
9236 elsif Present (Iface_Ctrl_F)
9237 and then Present (Prim_Ctrl_F)
9238 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
9242 -- Case of a procedure, or a function whose result type matches the
9243 -- result type of the interface primitive, or a function that has no
9244 -- controlling result (I or access I).
9246 elsif Ekind (Iface_Prim) = E_Procedure
9247 or else Etype (Prim) = Etype (Iface_Prim)
9248 or else not Has_Controlling_Result (Prim)
9250 return Type_Conformant
9251 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
9253 -- Case of a function returning an interface, or an access to one. Check
9254 -- that the return types correspond.
9256 elsif Implements_Interface (Typ, Iface) then
9257 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
9259 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
9264 Type_Conformant (Prim, Ultimate_Alias (Iface_Prim),
9265 Skip_Controlling_Formals => True);
9271 end Is_Interface_Conformant;
9273 ---------------------------------
9274 -- Is_Non_Overriding_Operation --
9275 ---------------------------------
9277 function Is_Non_Overriding_Operation
9278 (Prev_E : Entity_Id;
9279 New_E : Entity_Id) return Boolean
9283 G_Typ : Entity_Id := Empty;
9285 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
9286 -- If F_Type is a derived type associated with a generic actual subtype,
9287 -- then return its Generic_Parent_Type attribute, else return Empty.
9289 function Types_Correspond
9290 (P_Type : Entity_Id;
9291 N_Type : Entity_Id) return Boolean;
9292 -- Returns true if and only if the types (or designated types in the
9293 -- case of anonymous access types) are the same or N_Type is derived
9294 -- directly or indirectly from P_Type.
9296 -----------------------------
9297 -- Get_Generic_Parent_Type --
9298 -----------------------------
9300 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
9306 if Is_Derived_Type (F_Typ)
9307 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
9309 -- The tree must be traversed to determine the parent subtype in
9310 -- the generic unit, which unfortunately isn't always available
9311 -- via semantic attributes. ??? (Note: The use of Original_Node
9312 -- is needed for cases where a full derived type has been
9315 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
9316 if Nkind (Defn) = N_Derived_Type_Definition then
9317 Indic := Subtype_Indication (Defn);
9319 if Nkind (Indic) = N_Subtype_Indication then
9320 G_Typ := Entity (Subtype_Mark (Indic));
9322 G_Typ := Entity (Indic);
9325 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
9326 and then Present (Generic_Parent_Type (Parent (G_Typ)))
9328 return Generic_Parent_Type (Parent (G_Typ));
9334 end Get_Generic_Parent_Type;
9336 ----------------------
9337 -- Types_Correspond --
9338 ----------------------
9340 function Types_Correspond
9341 (P_Type : Entity_Id;
9342 N_Type : Entity_Id) return Boolean
9344 Prev_Type : Entity_Id := Base_Type (P_Type);
9345 New_Type : Entity_Id := Base_Type (N_Type);
9348 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
9349 Prev_Type := Designated_Type (Prev_Type);
9352 if Ekind (New_Type) = E_Anonymous_Access_Type then
9353 New_Type := Designated_Type (New_Type);
9356 if Prev_Type = New_Type then
9359 elsif not Is_Class_Wide_Type (New_Type) then
9360 while Etype (New_Type) /= New_Type loop
9361 New_Type := Etype (New_Type);
9362 if New_Type = Prev_Type then
9368 end Types_Correspond;
9370 -- Start of processing for Is_Non_Overriding_Operation
9373 -- In the case where both operations are implicit derived subprograms
9374 -- then neither overrides the other. This can only occur in certain
9375 -- obscure cases (e.g., derivation from homographs created in a generic
9378 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
9381 elsif Ekind (Current_Scope) = E_Package
9382 and then Is_Generic_Instance (Current_Scope)
9383 and then In_Private_Part (Current_Scope)
9384 and then Comes_From_Source (New_E)
9386 -- We examine the formals and result type of the inherited operation,
9387 -- to determine whether their type is derived from (the instance of)
9388 -- a generic type. The first such formal or result type is the one
9391 Formal := First_Formal (Prev_E);
9392 while Present (Formal) loop
9393 F_Typ := Base_Type (Etype (Formal));
9395 if Ekind (F_Typ) = E_Anonymous_Access_Type then
9396 F_Typ := Designated_Type (F_Typ);
9399 G_Typ := Get_Generic_Parent_Type (F_Typ);
9400 exit when Present (G_Typ);
9402 Next_Formal (Formal);
9405 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
9406 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
9413 -- If the generic type is a private type, then the original operation
9414 -- was not overriding in the generic, because there was no primitive
9415 -- operation to override.
9417 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
9418 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
9419 N_Formal_Private_Type_Definition
9423 -- The generic parent type is the ancestor of a formal derived
9424 -- type declaration. We need to check whether it has a primitive
9425 -- operation that should be overridden by New_E in the generic.
9429 P_Formal : Entity_Id;
9430 N_Formal : Entity_Id;
9434 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
9437 while Present (Prim_Elt) loop
9438 P_Prim := Node (Prim_Elt);
9440 if Chars (P_Prim) = Chars (New_E)
9441 and then Ekind (P_Prim) = Ekind (New_E)
9443 P_Formal := First_Formal (P_Prim);
9444 N_Formal := First_Formal (New_E);
9445 while Present (P_Formal) and then Present (N_Formal) loop
9446 P_Typ := Etype (P_Formal);
9447 N_Typ := Etype (N_Formal);
9449 if not Types_Correspond (P_Typ, N_Typ) then
9453 Next_Entity (P_Formal);
9454 Next_Entity (N_Formal);
9457 -- Found a matching primitive operation belonging to the
9458 -- formal ancestor type, so the new subprogram is
9462 and then No (N_Formal)
9463 and then (Ekind (New_E) /= E_Function
9466 (Etype (P_Prim), Etype (New_E)))
9472 Next_Elmt (Prim_Elt);
9475 -- If no match found, then the new subprogram does not override
9476 -- in the generic (nor in the instance).
9478 -- If the type in question is not abstract, and the subprogram
9479 -- is, this will be an error if the new operation is in the
9480 -- private part of the instance. Emit a warning now, which will
9481 -- make the subsequent error message easier to understand.
9483 if not Is_Abstract_Type (F_Typ)
9484 and then Is_Abstract_Subprogram (Prev_E)
9485 and then In_Private_Part (Current_Scope)
9487 Error_Msg_Node_2 := F_Typ;
9489 ("private operation& in generic unit does not override " &
9490 "any primitive operation of& (RM 12.3 (18))??",
9500 end Is_Non_Overriding_Operation;
9502 -------------------------------------
9503 -- List_Inherited_Pre_Post_Aspects --
9504 -------------------------------------
9506 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
9508 if Opt.List_Inherited_Aspects
9509 and then (Is_Subprogram (E) or else Is_Generic_Subprogram (E))
9512 Inherited : constant Subprogram_List := Inherited_Subprograms (E);
9516 for J in Inherited'Range loop
9517 P := Pre_Post_Conditions (Contract (Inherited (J)));
9518 while Present (P) loop
9519 Error_Msg_Sloc := Sloc (P);
9521 if Class_Present (P) and then not Split_PPC (P) then
9522 if Pragma_Name (P) = Name_Precondition then
9524 ("info: & inherits `Pre''Class` aspect from #?L?",
9528 ("info: & inherits `Post''Class` aspect from #?L?",
9533 P := Next_Pragma (P);
9538 end List_Inherited_Pre_Post_Aspects;
9540 ------------------------------
9541 -- Make_Inequality_Operator --
9542 ------------------------------
9544 -- S is the defining identifier of an equality operator. We build a
9545 -- subprogram declaration with the right signature. This operation is
9546 -- intrinsic, because it is always expanded as the negation of the
9547 -- call to the equality function.
9549 procedure Make_Inequality_Operator (S : Entity_Id) is
9550 Loc : constant Source_Ptr := Sloc (S);
9553 Op_Name : Entity_Id;
9555 FF : constant Entity_Id := First_Formal (S);
9556 NF : constant Entity_Id := Next_Formal (FF);
9559 -- Check that equality was properly defined, ignore call if not
9566 A : constant Entity_Id :=
9567 Make_Defining_Identifier (Sloc (FF),
9568 Chars => Chars (FF));
9570 B : constant Entity_Id :=
9571 Make_Defining_Identifier (Sloc (NF),
9572 Chars => Chars (NF));
9575 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
9577 Formals := New_List (
9578 Make_Parameter_Specification (Loc,
9579 Defining_Identifier => A,
9581 New_Reference_To (Etype (First_Formal (S)),
9582 Sloc (Etype (First_Formal (S))))),
9584 Make_Parameter_Specification (Loc,
9585 Defining_Identifier => B,
9587 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
9588 Sloc (Etype (Next_Formal (First_Formal (S)))))));
9591 Make_Subprogram_Declaration (Loc,
9593 Make_Function_Specification (Loc,
9594 Defining_Unit_Name => Op_Name,
9595 Parameter_Specifications => Formals,
9596 Result_Definition =>
9597 New_Reference_To (Standard_Boolean, Loc)));
9599 -- Insert inequality right after equality if it is explicit or after
9600 -- the derived type when implicit. These entities are created only
9601 -- for visibility purposes, and eventually replaced in the course
9602 -- of expansion, so they do not need to be attached to the tree and
9603 -- seen by the back-end. Keeping them internal also avoids spurious
9604 -- freezing problems. The declaration is inserted in the tree for
9605 -- analysis, and removed afterwards. If the equality operator comes
9606 -- from an explicit declaration, attach the inequality immediately
9607 -- after. Else the equality is inherited from a derived type
9608 -- declaration, so insert inequality after that declaration.
9610 if No (Alias (S)) then
9611 Insert_After (Unit_Declaration_Node (S), Decl);
9612 elsif Is_List_Member (Parent (S)) then
9613 Insert_After (Parent (S), Decl);
9615 Insert_After (Parent (Etype (First_Formal (S))), Decl);
9618 Mark_Rewrite_Insertion (Decl);
9619 Set_Is_Intrinsic_Subprogram (Op_Name);
9622 Set_Has_Completion (Op_Name);
9623 Set_Corresponding_Equality (Op_Name, S);
9624 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
9626 end Make_Inequality_Operator;
9628 ----------------------
9629 -- May_Need_Actuals --
9630 ----------------------
9632 procedure May_Need_Actuals (Fun : Entity_Id) is
9637 F := First_Formal (Fun);
9639 while Present (F) loop
9640 if No (Default_Value (F)) then
9648 Set_Needs_No_Actuals (Fun, B);
9649 end May_Need_Actuals;
9651 ---------------------
9652 -- Mode_Conformant --
9653 ---------------------
9655 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
9658 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
9660 end Mode_Conformant;
9662 ---------------------------
9663 -- New_Overloaded_Entity --
9664 ---------------------------
9666 procedure New_Overloaded_Entity
9668 Derived_Type : Entity_Id := Empty)
9670 Overridden_Subp : Entity_Id := Empty;
9671 -- Set if the current scope has an operation that is type-conformant
9672 -- with S, and becomes hidden by S.
9674 Is_Primitive_Subp : Boolean;
9675 -- Set to True if the new subprogram is primitive
9678 -- Entity that S overrides
9680 Prev_Vis : Entity_Id := Empty;
9681 -- Predecessor of E in Homonym chain
9683 procedure Check_For_Primitive_Subprogram
9684 (Is_Primitive : out Boolean;
9685 Is_Overriding : Boolean := False);
9686 -- If the subprogram being analyzed is a primitive operation of the type
9687 -- of a formal or result, set the Has_Primitive_Operations flag on the
9688 -- type, and set Is_Primitive to True (otherwise set to False). Set the
9689 -- corresponding flag on the entity itself for later use.
9691 procedure Check_Synchronized_Overriding
9692 (Def_Id : Entity_Id;
9693 Overridden_Subp : out Entity_Id);
9694 -- First determine if Def_Id is an entry or a subprogram either defined
9695 -- in the scope of a task or protected type, or is a primitive of such
9696 -- a type. Check whether Def_Id overrides a subprogram of an interface
9697 -- implemented by the synchronized type, return the overridden entity
9700 function Is_Private_Declaration (E : Entity_Id) return Boolean;
9701 -- Check that E is declared in the private part of the current package,
9702 -- or in the package body, where it may hide a previous declaration.
9703 -- We can't use In_Private_Part by itself because this flag is also
9704 -- set when freezing entities, so we must examine the place of the
9705 -- declaration in the tree, and recognize wrapper packages as well.
9707 function Is_Overriding_Alias
9709 New_E : Entity_Id) return Boolean;
9710 -- Check whether new subprogram and old subprogram are both inherited
9711 -- from subprograms that have distinct dispatch table entries. This can
9712 -- occur with derivations from instances with accidental homonyms. The
9713 -- function is conservative given that the converse is only true within
9714 -- instances that contain accidental overloadings.
9716 ------------------------------------
9717 -- Check_For_Primitive_Subprogram --
9718 ------------------------------------
9720 procedure Check_For_Primitive_Subprogram
9721 (Is_Primitive : out Boolean;
9722 Is_Overriding : Boolean := False)
9728 function Visible_Part_Type (T : Entity_Id) return Boolean;
9729 -- Returns true if T is declared in the visible part of the current
9730 -- package scope; otherwise returns false. Assumes that T is declared
9733 procedure Check_Private_Overriding (T : Entity_Id);
9734 -- Checks that if a primitive abstract subprogram of a visible
9735 -- abstract type is declared in a private part, then it must override
9736 -- an abstract subprogram declared in the visible part. Also checks
9737 -- that if a primitive function with a controlling result is declared
9738 -- in a private part, then it must override a function declared in
9739 -- the visible part.
9741 ------------------------------
9742 -- Check_Private_Overriding --
9743 ------------------------------
9745 procedure Check_Private_Overriding (T : Entity_Id) is
9747 if Is_Package_Or_Generic_Package (Current_Scope)
9748 and then In_Private_Part (Current_Scope)
9749 and then Visible_Part_Type (T)
9750 and then not In_Instance
9752 if Is_Abstract_Type (T)
9753 and then Is_Abstract_Subprogram (S)
9754 and then (not Is_Overriding
9755 or else not Is_Abstract_Subprogram (E))
9758 ("abstract subprograms must be visible "
9759 & "(RM 3.9.3(10))!", S);
9761 elsif Ekind (S) = E_Function and then not Is_Overriding then
9762 if Is_Tagged_Type (T) and then T = Base_Type (Etype (S)) then
9764 ("private function with tagged result must"
9765 & " override visible-part function", S);
9767 ("\move subprogram to the visible part"
9768 & " (RM 3.9.3(10))", S);
9770 -- AI05-0073: extend this test to the case of a function
9771 -- with a controlling access result.
9773 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
9774 and then Is_Tagged_Type (Designated_Type (Etype (S)))
9776 not Is_Class_Wide_Type (Designated_Type (Etype (S)))
9777 and then Ada_Version >= Ada_2012
9780 ("private function with controlling access result "
9781 & "must override visible-part function", S);
9783 ("\move subprogram to the visible part"
9784 & " (RM 3.9.3(10))", S);
9788 end Check_Private_Overriding;
9790 -----------------------
9791 -- Visible_Part_Type --
9792 -----------------------
9794 function Visible_Part_Type (T : Entity_Id) return Boolean is
9795 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
9799 -- If the entity is a private type, then it must be declared in a
9802 if Ekind (T) in Private_Kind then
9806 -- Otherwise, we traverse the visible part looking for its
9807 -- corresponding declaration. We cannot use the declaration
9808 -- node directly because in the private part the entity of a
9809 -- private type is the one in the full view, which does not
9810 -- indicate that it is the completion of something visible.
9812 N := First (Visible_Declarations (Specification (P)));
9813 while Present (N) loop
9814 if Nkind (N) = N_Full_Type_Declaration
9815 and then Present (Defining_Identifier (N))
9816 and then T = Defining_Identifier (N)
9820 elsif Nkind_In (N, N_Private_Type_Declaration,
9821 N_Private_Extension_Declaration)
9822 and then Present (Defining_Identifier (N))
9823 and then T = Full_View (Defining_Identifier (N))
9832 end Visible_Part_Type;
9834 -- Start of processing for Check_For_Primitive_Subprogram
9837 Is_Primitive := False;
9839 if not Comes_From_Source (S) then
9842 -- If subprogram is at library level, it is not primitive operation
9844 elsif Current_Scope = Standard_Standard then
9847 elsif (Is_Package_Or_Generic_Package (Current_Scope)
9848 and then not In_Package_Body (Current_Scope))
9849 or else Is_Overriding
9851 -- For function, check return type
9853 if Ekind (S) = E_Function then
9854 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
9855 F_Typ := Designated_Type (Etype (S));
9860 B_Typ := Base_Type (F_Typ);
9862 if Scope (B_Typ) = Current_Scope
9863 and then not Is_Class_Wide_Type (B_Typ)
9864 and then not Is_Generic_Type (B_Typ)
9866 Is_Primitive := True;
9867 Set_Has_Primitive_Operations (B_Typ);
9868 Set_Is_Primitive (S);
9869 Check_Private_Overriding (B_Typ);
9873 -- For all subprograms, check formals
9875 Formal := First_Formal (S);
9876 while Present (Formal) loop
9877 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
9878 F_Typ := Designated_Type (Etype (Formal));
9880 F_Typ := Etype (Formal);
9883 B_Typ := Base_Type (F_Typ);
9885 if Ekind (B_Typ) = E_Access_Subtype then
9886 B_Typ := Base_Type (B_Typ);
9889 if Scope (B_Typ) = Current_Scope
9890 and then not Is_Class_Wide_Type (B_Typ)
9891 and then not Is_Generic_Type (B_Typ)
9893 Is_Primitive := True;
9894 Set_Is_Primitive (S);
9895 Set_Has_Primitive_Operations (B_Typ);
9896 Check_Private_Overriding (B_Typ);
9899 Next_Formal (Formal);
9902 -- Special case: An equality function can be redefined for a type
9903 -- occurring in a declarative part, and won't otherwise be treated as
9904 -- a primitive because it doesn't occur in a package spec and doesn't
9905 -- override an inherited subprogram. It's important that we mark it
9906 -- primitive so it can be returned by Collect_Primitive_Operations
9907 -- and be used in composing the equality operation of later types
9908 -- that have a component of the type.
9910 elsif Chars (S) = Name_Op_Eq
9911 and then Etype (S) = Standard_Boolean
9913 B_Typ := Base_Type (Etype (First_Formal (S)));
9915 if Scope (B_Typ) = Current_Scope
9917 Base_Type (Etype (Next_Formal (First_Formal (S)))) = B_Typ
9918 and then not Is_Limited_Type (B_Typ)
9920 Is_Primitive := True;
9921 Set_Is_Primitive (S);
9922 Set_Has_Primitive_Operations (B_Typ);
9923 Check_Private_Overriding (B_Typ);
9926 end Check_For_Primitive_Subprogram;
9928 -----------------------------------
9929 -- Check_Synchronized_Overriding --
9930 -----------------------------------
9932 procedure Check_Synchronized_Overriding
9933 (Def_Id : Entity_Id;
9934 Overridden_Subp : out Entity_Id)
9936 Ifaces_List : Elist_Id;
9940 function Matches_Prefixed_View_Profile
9941 (Prim_Params : List_Id;
9942 Iface_Params : List_Id) return Boolean;
9943 -- Determine whether a subprogram's parameter profile Prim_Params
9944 -- matches that of a potentially overridden interface subprogram
9945 -- Iface_Params. Also determine if the type of first parameter of
9946 -- Iface_Params is an implemented interface.
9948 -----------------------------------
9949 -- Matches_Prefixed_View_Profile --
9950 -----------------------------------
9952 function Matches_Prefixed_View_Profile
9953 (Prim_Params : List_Id;
9954 Iface_Params : List_Id) return Boolean
9956 Iface_Id : Entity_Id;
9957 Iface_Param : Node_Id;
9958 Iface_Typ : Entity_Id;
9959 Prim_Id : Entity_Id;
9960 Prim_Param : Node_Id;
9961 Prim_Typ : Entity_Id;
9963 function Is_Implemented
9964 (Ifaces_List : Elist_Id;
9965 Iface : Entity_Id) return Boolean;
9966 -- Determine if Iface is implemented by the current task or
9969 --------------------
9970 -- Is_Implemented --
9971 --------------------
9973 function Is_Implemented
9974 (Ifaces_List : Elist_Id;
9975 Iface : Entity_Id) return Boolean
9977 Iface_Elmt : Elmt_Id;
9980 Iface_Elmt := First_Elmt (Ifaces_List);
9981 while Present (Iface_Elmt) loop
9982 if Node (Iface_Elmt) = Iface then
9986 Next_Elmt (Iface_Elmt);
9992 -- Start of processing for Matches_Prefixed_View_Profile
9995 Iface_Param := First (Iface_Params);
9996 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
9998 if Is_Access_Type (Iface_Typ) then
9999 Iface_Typ := Designated_Type (Iface_Typ);
10002 Prim_Param := First (Prim_Params);
10004 -- The first parameter of the potentially overridden subprogram
10005 -- must be an interface implemented by Prim.
10007 if not Is_Interface (Iface_Typ)
10008 or else not Is_Implemented (Ifaces_List, Iface_Typ)
10013 -- The checks on the object parameters are done, move onto the
10014 -- rest of the parameters.
10016 if not In_Scope then
10017 Prim_Param := Next (Prim_Param);
10020 Iface_Param := Next (Iface_Param);
10021 while Present (Iface_Param) and then Present (Prim_Param) loop
10022 Iface_Id := Defining_Identifier (Iface_Param);
10023 Iface_Typ := Find_Parameter_Type (Iface_Param);
10025 Prim_Id := Defining_Identifier (Prim_Param);
10026 Prim_Typ := Find_Parameter_Type (Prim_Param);
10028 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
10029 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
10030 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
10032 Iface_Typ := Designated_Type (Iface_Typ);
10033 Prim_Typ := Designated_Type (Prim_Typ);
10036 -- Case of multiple interface types inside a parameter profile
10038 -- (Obj_Param : in out Iface; ...; Param : Iface)
10040 -- If the interface type is implemented, then the matching type
10041 -- in the primitive should be the implementing record type.
10043 if Ekind (Iface_Typ) = E_Record_Type
10044 and then Is_Interface (Iface_Typ)
10045 and then Is_Implemented (Ifaces_List, Iface_Typ)
10047 if Prim_Typ /= Typ then
10051 -- The two parameters must be both mode and subtype conformant
10053 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
10055 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
10060 Next (Iface_Param);
10064 -- One of the two lists contains more parameters than the other
10066 if Present (Iface_Param) or else Present (Prim_Param) then
10071 end Matches_Prefixed_View_Profile;
10073 -- Start of processing for Check_Synchronized_Overriding
10076 Overridden_Subp := Empty;
10078 -- Def_Id must be an entry or a subprogram. We should skip predefined
10079 -- primitives internally generated by the frontend; however at this
10080 -- stage predefined primitives are still not fully decorated. As a
10081 -- minor optimization we skip here internally generated subprograms.
10083 if (Ekind (Def_Id) /= E_Entry
10084 and then Ekind (Def_Id) /= E_Function
10085 and then Ekind (Def_Id) /= E_Procedure)
10086 or else not Comes_From_Source (Def_Id)
10091 -- Search for the concurrent declaration since it contains the list
10092 -- of all implemented interfaces. In this case, the subprogram is
10093 -- declared within the scope of a protected or a task type.
10095 if Present (Scope (Def_Id))
10096 and then Is_Concurrent_Type (Scope (Def_Id))
10097 and then not Is_Generic_Actual_Type (Scope (Def_Id))
10099 Typ := Scope (Def_Id);
10102 -- The enclosing scope is not a synchronized type and the subprogram
10105 elsif No (First_Formal (Def_Id)) then
10108 -- The subprogram has formals and hence it may be a primitive of a
10109 -- concurrent type.
10112 Typ := Etype (First_Formal (Def_Id));
10114 if Is_Access_Type (Typ) then
10115 Typ := Directly_Designated_Type (Typ);
10118 if Is_Concurrent_Type (Typ)
10119 and then not Is_Generic_Actual_Type (Typ)
10123 -- This case occurs when the concurrent type is declared within
10124 -- a generic unit. As a result the corresponding record has been
10125 -- built and used as the type of the first formal, we just have
10126 -- to retrieve the corresponding concurrent type.
10128 elsif Is_Concurrent_Record_Type (Typ)
10129 and then not Is_Class_Wide_Type (Typ)
10130 and then Present (Corresponding_Concurrent_Type (Typ))
10132 Typ := Corresponding_Concurrent_Type (Typ);
10140 -- There is no overriding to check if is an inherited operation in a
10141 -- type derivation on for a generic actual.
10143 Collect_Interfaces (Typ, Ifaces_List);
10145 if Is_Empty_Elmt_List (Ifaces_List) then
10149 -- Determine whether entry or subprogram Def_Id overrides a primitive
10150 -- operation that belongs to one of the interfaces in Ifaces_List.
10153 Candidate : Entity_Id := Empty;
10154 Hom : Entity_Id := Empty;
10155 Iface_Typ : Entity_Id;
10156 Subp : Entity_Id := Empty;
10159 -- Traverse the homonym chain, looking for a potentially
10160 -- overridden subprogram that belongs to an implemented
10163 Hom := Current_Entity_In_Scope (Def_Id);
10164 while Present (Hom) loop
10168 or else not Is_Overloadable (Subp)
10169 or else not Is_Primitive (Subp)
10170 or else not Is_Dispatching_Operation (Subp)
10171 or else not Present (Find_Dispatching_Type (Subp))
10172 or else not Is_Interface (Find_Dispatching_Type (Subp))
10176 -- Entries and procedures can override abstract or null
10177 -- interface procedures.
10179 elsif (Ekind (Def_Id) = E_Procedure
10180 or else Ekind (Def_Id) = E_Entry)
10181 and then Ekind (Subp) = E_Procedure
10182 and then Matches_Prefixed_View_Profile
10183 (Parameter_Specifications (Parent (Def_Id)),
10184 Parameter_Specifications (Parent (Subp)))
10188 -- For an overridden subprogram Subp, check whether the mode
10189 -- of its first parameter is correct depending on the kind
10190 -- of synchronized type.
10193 Formal : constant Node_Id := First_Formal (Candidate);
10196 -- In order for an entry or a protected procedure to
10197 -- override, the first parameter of the overridden
10198 -- routine must be of mode "out", "in out" or
10199 -- access-to-variable.
10201 if Ekind_In (Candidate, E_Entry, E_Procedure)
10202 and then Is_Protected_Type (Typ)
10203 and then Ekind (Formal) /= E_In_Out_Parameter
10204 and then Ekind (Formal) /= E_Out_Parameter
10205 and then Nkind (Parameter_Type (Parent (Formal))) /=
10206 N_Access_Definition
10210 -- All other cases are OK since a task entry or routine
10211 -- does not have a restriction on the mode of the first
10212 -- parameter of the overridden interface routine.
10215 Overridden_Subp := Candidate;
10220 -- Functions can override abstract interface functions
10222 elsif Ekind (Def_Id) = E_Function
10223 and then Ekind (Subp) = E_Function
10224 and then Matches_Prefixed_View_Profile
10225 (Parameter_Specifications (Parent (Def_Id)),
10226 Parameter_Specifications (Parent (Subp)))
10227 and then Etype (Result_Definition (Parent (Def_Id))) =
10228 Etype (Result_Definition (Parent (Subp)))
10230 Overridden_Subp := Subp;
10234 Hom := Homonym (Hom);
10237 -- After examining all candidates for overriding, we are left with
10238 -- the best match which is a mode incompatible interface routine.
10239 -- Do not emit an error if the Expander is active since this error
10240 -- will be detected later on after all concurrent types are
10241 -- expanded and all wrappers are built. This check is meant for
10242 -- spec-only compilations.
10244 if Present (Candidate) and then not Expander_Active then
10246 Find_Parameter_Type (Parent (First_Formal (Candidate)));
10248 -- Def_Id is primitive of a protected type, declared inside the
10249 -- type, and the candidate is primitive of a limited or
10250 -- synchronized interface.
10253 and then Is_Protected_Type (Typ)
10255 (Is_Limited_Interface (Iface_Typ)
10256 or else Is_Protected_Interface (Iface_Typ)
10257 or else Is_Synchronized_Interface (Iface_Typ)
10258 or else Is_Task_Interface (Iface_Typ))
10260 Error_Msg_PT (Parent (Typ), Candidate);
10264 Overridden_Subp := Candidate;
10267 end Check_Synchronized_Overriding;
10269 ----------------------------
10270 -- Is_Private_Declaration --
10271 ----------------------------
10273 function Is_Private_Declaration (E : Entity_Id) return Boolean is
10274 Priv_Decls : List_Id;
10275 Decl : constant Node_Id := Unit_Declaration_Node (E);
10278 if Is_Package_Or_Generic_Package (Current_Scope)
10279 and then In_Private_Part (Current_Scope)
10282 Private_Declarations
10283 (Specification (Unit_Declaration_Node (Current_Scope)));
10285 return In_Package_Body (Current_Scope)
10287 (Is_List_Member (Decl)
10288 and then List_Containing (Decl) = Priv_Decls)
10289 or else (Nkind (Parent (Decl)) = N_Package_Specification
10291 Is_Compilation_Unit
10292 (Defining_Entity (Parent (Decl)))
10293 and then List_Containing (Parent (Parent (Decl))) =
10298 end Is_Private_Declaration;
10300 --------------------------
10301 -- Is_Overriding_Alias --
10302 --------------------------
10304 function Is_Overriding_Alias
10305 (Old_E : Entity_Id;
10306 New_E : Entity_Id) return Boolean
10308 AO : constant Entity_Id := Alias (Old_E);
10309 AN : constant Entity_Id := Alias (New_E);
10312 return Scope (AO) /= Scope (AN)
10313 or else No (DTC_Entity (AO))
10314 or else No (DTC_Entity (AN))
10315 or else DT_Position (AO) = DT_Position (AN);
10316 end Is_Overriding_Alias;
10318 -- Start of processing for New_Overloaded_Entity
10321 -- We need to look for an entity that S may override. This must be a
10322 -- homonym in the current scope, so we look for the first homonym of
10323 -- S in the current scope as the starting point for the search.
10325 E := Current_Entity_In_Scope (S);
10327 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
10328 -- They are directly added to the list of primitive operations of
10329 -- Derived_Type, unless this is a rederivation in the private part
10330 -- of an operation that was already derived in the visible part of
10331 -- the current package.
10333 if Ada_Version >= Ada_2005
10334 and then Present (Derived_Type)
10335 and then Present (Alias (S))
10336 and then Is_Dispatching_Operation (Alias (S))
10337 and then Present (Find_Dispatching_Type (Alias (S)))
10338 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
10340 -- For private types, when the full-view is processed we propagate to
10341 -- the full view the non-overridden entities whose attribute "alias"
10342 -- references an interface primitive. These entities were added by
10343 -- Derive_Subprograms to ensure that interface primitives are
10346 -- Inside_Freeze_Actions is non zero when S corresponds with an
10347 -- internal entity that links an interface primitive with its
10348 -- covering primitive through attribute Interface_Alias (see
10349 -- Add_Internal_Interface_Entities).
10351 if Inside_Freezing_Actions = 0
10352 and then Is_Package_Or_Generic_Package (Current_Scope)
10353 and then In_Private_Part (Current_Scope)
10354 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
10355 and then Nkind (Parent (S)) = N_Full_Type_Declaration
10356 and then Full_View (Defining_Identifier (Parent (E)))
10357 = Defining_Identifier (Parent (S))
10358 and then Alias (E) = Alias (S)
10360 Check_Operation_From_Private_View (S, E);
10361 Set_Is_Dispatching_Operation (S);
10366 Enter_Overloaded_Entity (S);
10367 Check_Dispatching_Operation (S, Empty);
10368 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10374 -- If there is no homonym then this is definitely not overriding
10377 Enter_Overloaded_Entity (S);
10378 Check_Dispatching_Operation (S, Empty);
10379 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10381 -- If subprogram has an explicit declaration, check whether it has an
10382 -- overriding indicator.
10384 if Comes_From_Source (S) then
10385 Check_Synchronized_Overriding (S, Overridden_Subp);
10387 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
10388 -- it may have overridden some hidden inherited primitive. Update
10389 -- Overridden_Subp to avoid spurious errors when checking the
10390 -- overriding indicator.
10392 if Ada_Version >= Ada_2012
10393 and then No (Overridden_Subp)
10394 and then Is_Dispatching_Operation (S)
10395 and then Present (Overridden_Operation (S))
10397 Overridden_Subp := Overridden_Operation (S);
10400 Check_Overriding_Indicator
10401 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10404 -- If there is a homonym that is not overloadable, then we have an
10405 -- error, except for the special cases checked explicitly below.
10407 elsif not Is_Overloadable (E) then
10409 -- Check for spurious conflict produced by a subprogram that has the
10410 -- same name as that of the enclosing generic package. The conflict
10411 -- occurs within an instance, between the subprogram and the renaming
10412 -- declaration for the package. After the subprogram, the package
10413 -- renaming declaration becomes hidden.
10415 if Ekind (E) = E_Package
10416 and then Present (Renamed_Object (E))
10417 and then Renamed_Object (E) = Current_Scope
10418 and then Nkind (Parent (Renamed_Object (E))) =
10419 N_Package_Specification
10420 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
10423 Set_Is_Immediately_Visible (E, False);
10424 Enter_Overloaded_Entity (S);
10425 Set_Homonym (S, Homonym (E));
10426 Check_Dispatching_Operation (S, Empty);
10427 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
10429 -- If the subprogram is implicit it is hidden by the previous
10430 -- declaration. However if it is dispatching, it must appear in the
10431 -- dispatch table anyway, because it can be dispatched to even if it
10432 -- cannot be called directly.
10434 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
10435 Set_Scope (S, Current_Scope);
10437 if Is_Dispatching_Operation (Alias (S)) then
10438 Check_Dispatching_Operation (S, Empty);
10444 Error_Msg_Sloc := Sloc (E);
10446 -- Generate message, with useful additional warning if in generic
10448 if Is_Generic_Unit (E) then
10449 Error_Msg_N ("previous generic unit cannot be overloaded", S);
10450 Error_Msg_N ("\& conflicts with declaration#", S);
10452 Error_Msg_N ("& conflicts with declaration#", S);
10458 -- E exists and is overloadable
10461 Check_Synchronized_Overriding (S, Overridden_Subp);
10463 -- Loop through E and its homonyms to determine if any of them is
10464 -- the candidate for overriding by S.
10466 while Present (E) loop
10468 -- Definitely not interesting if not in the current scope
10470 if Scope (E) /= Current_Scope then
10473 -- Ada 2012 (AI05-0165): For internally generated bodies of null
10474 -- procedures locate the internally generated spec. We enforce
10475 -- mode conformance since a tagged type may inherit from
10476 -- interfaces several null primitives which differ only in
10477 -- the mode of the formals.
10479 elsif not Comes_From_Source (S)
10480 and then Is_Null_Procedure (S)
10481 and then not Mode_Conformant (E, S)
10485 -- Check if we have type conformance
10487 elsif Type_Conformant (E, S) then
10489 -- If the old and new entities have the same profile and one
10490 -- is not the body of the other, then this is an error, unless
10491 -- one of them is implicitly declared.
10493 -- There are some cases when both can be implicit, for example
10494 -- when both a literal and a function that overrides it are
10495 -- inherited in a derivation, or when an inherited operation
10496 -- of a tagged full type overrides the inherited operation of
10497 -- a private extension. Ada 83 had a special rule for the
10498 -- literal case. In Ada 95, the later implicit operation hides
10499 -- the former, and the literal is always the former. In the
10500 -- odd case where both are derived operations declared at the
10501 -- same point, both operations should be declared, and in that
10502 -- case we bypass the following test and proceed to the next
10503 -- part. This can only occur for certain obscure cases in
10504 -- instances, when an operation on a type derived from a formal
10505 -- private type does not override a homograph inherited from
10506 -- the actual. In subsequent derivations of such a type, the
10507 -- DT positions of these operations remain distinct, if they
10510 if Present (Alias (S))
10511 and then (No (Alias (E))
10512 or else Comes_From_Source (E)
10513 or else Is_Abstract_Subprogram (S)
10515 (Is_Dispatching_Operation (E)
10516 and then Is_Overriding_Alias (E, S)))
10517 and then Ekind (E) /= E_Enumeration_Literal
10519 -- When an derived operation is overloaded it may be due to
10520 -- the fact that the full view of a private extension
10521 -- re-inherits. It has to be dealt with.
10523 if Is_Package_Or_Generic_Package (Current_Scope)
10524 and then In_Private_Part (Current_Scope)
10526 Check_Operation_From_Private_View (S, E);
10529 -- In any case the implicit operation remains hidden by the
10530 -- existing declaration, which is overriding. Indicate that
10531 -- E overrides the operation from which S is inherited.
10533 if Present (Alias (S)) then
10534 Set_Overridden_Operation (E, Alias (S));
10536 Set_Overridden_Operation (E, S);
10539 if Comes_From_Source (E) then
10540 Check_Overriding_Indicator (E, S, Is_Primitive => False);
10545 -- Within an instance, the renaming declarations for actual
10546 -- subprograms may become ambiguous, but they do not hide each
10549 elsif Ekind (E) /= E_Entry
10550 and then not Comes_From_Source (E)
10551 and then not Is_Generic_Instance (E)
10552 and then (Present (Alias (E))
10553 or else Is_Intrinsic_Subprogram (E))
10554 and then (not In_Instance
10555 or else No (Parent (E))
10556 or else Nkind (Unit_Declaration_Node (E)) /=
10557 N_Subprogram_Renaming_Declaration)
10559 -- A subprogram child unit is not allowed to override an
10560 -- inherited subprogram (10.1.1(20)).
10562 if Is_Child_Unit (S) then
10564 ("child unit overrides inherited subprogram in parent",
10569 if Is_Non_Overriding_Operation (E, S) then
10570 Enter_Overloaded_Entity (S);
10572 if No (Derived_Type)
10573 or else Is_Tagged_Type (Derived_Type)
10575 Check_Dispatching_Operation (S, Empty);
10581 -- E is a derived operation or an internal operator which
10582 -- is being overridden. Remove E from further visibility.
10583 -- Furthermore, if E is a dispatching operation, it must be
10584 -- replaced in the list of primitive operations of its type
10585 -- (see Override_Dispatching_Operation).
10587 Overridden_Subp := E;
10593 Prev := First_Entity (Current_Scope);
10594 while Present (Prev) and then Next_Entity (Prev) /= E loop
10595 Next_Entity (Prev);
10598 -- It is possible for E to be in the current scope and
10599 -- yet not in the entity chain. This can only occur in a
10600 -- generic context where E is an implicit concatenation
10601 -- in the formal part, because in a generic body the
10602 -- entity chain starts with the formals.
10605 (Present (Prev) or else Chars (E) = Name_Op_Concat);
10607 -- E must be removed both from the entity_list of the
10608 -- current scope, and from the visibility chain
10610 if Debug_Flag_E then
10611 Write_Str ("Override implicit operation ");
10612 Write_Int (Int (E));
10616 -- If E is a predefined concatenation, it stands for four
10617 -- different operations. As a result, a single explicit
10618 -- declaration does not hide it. In a possible ambiguous
10619 -- situation, Disambiguate chooses the user-defined op,
10620 -- so it is correct to retain the previous internal one.
10622 if Chars (E) /= Name_Op_Concat
10623 or else Ekind (E) /= E_Operator
10625 -- For nondispatching derived operations that are
10626 -- overridden by a subprogram declared in the private
10627 -- part of a package, we retain the derived subprogram
10628 -- but mark it as not immediately visible. If the
10629 -- derived operation was declared in the visible part
10630 -- then this ensures that it will still be visible
10631 -- outside the package with the proper signature
10632 -- (calls from outside must also be directed to this
10633 -- version rather than the overriding one, unlike the
10634 -- dispatching case). Calls from inside the package
10635 -- will still resolve to the overriding subprogram
10636 -- since the derived one is marked as not visible
10637 -- within the package.
10639 -- If the private operation is dispatching, we achieve
10640 -- the overriding by keeping the implicit operation
10641 -- but setting its alias to be the overriding one. In
10642 -- this fashion the proper body is executed in all
10643 -- cases, but the original signature is used outside
10646 -- If the overriding is not in the private part, we
10647 -- remove the implicit operation altogether.
10649 if Is_Private_Declaration (S) then
10650 if not Is_Dispatching_Operation (E) then
10651 Set_Is_Immediately_Visible (E, False);
10653 -- Work done in Override_Dispatching_Operation,
10654 -- so nothing else needs to be done here.
10660 -- Find predecessor of E in Homonym chain
10662 if E = Current_Entity (E) then
10665 Prev_Vis := Current_Entity (E);
10666 while Homonym (Prev_Vis) /= E loop
10667 Prev_Vis := Homonym (Prev_Vis);
10671 if Prev_Vis /= Empty then
10673 -- Skip E in the visibility chain
10675 Set_Homonym (Prev_Vis, Homonym (E));
10678 Set_Name_Entity_Id (Chars (E), Homonym (E));
10681 Set_Next_Entity (Prev, Next_Entity (E));
10683 if No (Next_Entity (Prev)) then
10684 Set_Last_Entity (Current_Scope, Prev);
10689 Enter_Overloaded_Entity (S);
10691 -- For entities generated by Derive_Subprograms the
10692 -- overridden operation is the inherited primitive
10693 -- (which is available through the attribute alias).
10695 if not (Comes_From_Source (E))
10696 and then Is_Dispatching_Operation (E)
10697 and then Find_Dispatching_Type (E) =
10698 Find_Dispatching_Type (S)
10699 and then Present (Alias (E))
10700 and then Comes_From_Source (Alias (E))
10702 Set_Overridden_Operation (S, Alias (E));
10704 -- Normal case of setting entity as overridden
10706 -- Note: Static_Initialization and Overridden_Operation
10707 -- attributes use the same field in subprogram entities.
10708 -- Static_Initialization is only defined for internal
10709 -- initialization procedures, where Overridden_Operation
10710 -- is irrelevant. Therefore the setting of this attribute
10711 -- must check whether the target is an init_proc.
10713 elsif not Is_Init_Proc (S) then
10714 Set_Overridden_Operation (S, E);
10717 Check_Overriding_Indicator (S, E, Is_Primitive => True);
10719 -- If S is a user-defined subprogram or a null procedure
10720 -- expanded to override an inherited null procedure, or a
10721 -- predefined dispatching primitive then indicate that E
10722 -- overrides the operation from which S is inherited.
10724 if Comes_From_Source (S)
10726 (Present (Parent (S))
10728 Nkind (Parent (S)) = N_Procedure_Specification
10730 Null_Present (Parent (S)))
10732 (Present (Alias (E))
10734 Is_Predefined_Dispatching_Operation (Alias (E)))
10736 if Present (Alias (E)) then
10737 Set_Overridden_Operation (S, Alias (E));
10741 if Is_Dispatching_Operation (E) then
10743 -- An overriding dispatching subprogram inherits the
10744 -- convention of the overridden subprogram (AI-117).
10746 Set_Convention (S, Convention (E));
10747 Check_Dispatching_Operation (S, E);
10750 Check_Dispatching_Operation (S, Empty);
10753 Check_For_Primitive_Subprogram
10754 (Is_Primitive_Subp, Is_Overriding => True);
10755 goto Check_Inequality;
10758 -- Apparent redeclarations in instances can occur when two
10759 -- formal types get the same actual type. The subprograms in
10760 -- in the instance are legal, even if not callable from the
10761 -- outside. Calls from within are disambiguated elsewhere.
10762 -- For dispatching operations in the visible part, the usual
10763 -- rules apply, and operations with the same profile are not
10764 -- legal (B830001).
10766 elsif (In_Instance_Visible_Part
10767 and then not Is_Dispatching_Operation (E))
10768 or else In_Instance_Not_Visible
10772 -- Here we have a real error (identical profile)
10775 Error_Msg_Sloc := Sloc (E);
10777 -- Avoid cascaded errors if the entity appears in
10778 -- subsequent calls.
10780 Set_Scope (S, Current_Scope);
10782 -- Generate error, with extra useful warning for the case
10783 -- of a generic instance with no completion.
10785 if Is_Generic_Instance (S)
10786 and then not Has_Completion (E)
10789 ("instantiation cannot provide body for&", S);
10790 Error_Msg_N ("\& conflicts with declaration#", S);
10792 Error_Msg_N ("& conflicts with declaration#", S);
10799 -- If one subprogram has an access parameter and the other
10800 -- a parameter of an access type, calls to either might be
10801 -- ambiguous. Verify that parameters match except for the
10802 -- access parameter.
10804 if May_Hide_Profile then
10810 F1 := First_Formal (S);
10811 F2 := First_Formal (E);
10812 while Present (F1) and then Present (F2) loop
10813 if Is_Access_Type (Etype (F1)) then
10814 if not Is_Access_Type (Etype (F2))
10815 or else not Conforming_Types
10816 (Designated_Type (Etype (F1)),
10817 Designated_Type (Etype (F2)),
10820 May_Hide_Profile := False;
10824 not Conforming_Types
10825 (Etype (F1), Etype (F2), Type_Conformant)
10827 May_Hide_Profile := False;
10834 if May_Hide_Profile
10838 Error_Msg_NE ("calls to& may be ambiguous??", S, S);
10847 -- On exit, we know that S is a new entity
10849 Enter_Overloaded_Entity (S);
10850 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
10851 Check_Overriding_Indicator
10852 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
10854 -- Overloading is not allowed in SPARK, except for operators
10856 if Nkind (S) /= N_Defining_Operator_Symbol then
10857 Error_Msg_Sloc := Sloc (Homonym (S));
10858 Check_SPARK_Restriction
10859 ("overloading not allowed with entity#", S);
10862 -- If S is a derived operation for an untagged type then by
10863 -- definition it's not a dispatching operation (even if the parent
10864 -- operation was dispatching), so Check_Dispatching_Operation is not
10865 -- called in that case.
10867 if No (Derived_Type)
10868 or else Is_Tagged_Type (Derived_Type)
10870 Check_Dispatching_Operation (S, Empty);
10874 -- If this is a user-defined equality operator that is not a derived
10875 -- subprogram, create the corresponding inequality. If the operation is
10876 -- dispatching, the expansion is done elsewhere, and we do not create
10877 -- an explicit inequality operation.
10879 <<Check_Inequality>>
10880 if Chars (S) = Name_Op_Eq
10881 and then Etype (S) = Standard_Boolean
10882 and then Present (Parent (S))
10883 and then not Is_Dispatching_Operation (S)
10885 Make_Inequality_Operator (S);
10887 if Ada_Version >= Ada_2012 then
10888 Check_Untagged_Equality (S);
10891 end New_Overloaded_Entity;
10893 ---------------------
10894 -- Process_Formals --
10895 ---------------------
10897 procedure Process_Formals
10899 Related_Nod : Node_Id)
10901 Param_Spec : Node_Id;
10902 Formal : Entity_Id;
10903 Formal_Type : Entity_Id;
10907 Num_Out_Params : Nat := 0;
10908 First_Out_Param : Entity_Id := Empty;
10909 -- Used for setting Is_Only_Out_Parameter
10911 function Designates_From_With_Type (Typ : Entity_Id) return Boolean;
10912 -- Determine whether an access type designates a type coming from a
10915 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
10916 -- Check whether the default has a class-wide type. After analysis the
10917 -- default has the type of the formal, so we must also check explicitly
10918 -- for an access attribute.
10920 -------------------------------
10921 -- Designates_From_With_Type --
10922 -------------------------------
10924 function Designates_From_With_Type (Typ : Entity_Id) return Boolean is
10925 Desig : Entity_Id := Typ;
10928 if Is_Access_Type (Desig) then
10929 Desig := Directly_Designated_Type (Desig);
10932 if Is_Class_Wide_Type (Desig) then
10933 Desig := Root_Type (Desig);
10937 Ekind (Desig) = E_Incomplete_Type and then From_With_Type (Desig);
10938 end Designates_From_With_Type;
10940 ---------------------------
10941 -- Is_Class_Wide_Default --
10942 ---------------------------
10944 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
10946 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
10947 or else (Nkind (D) = N_Attribute_Reference
10948 and then Attribute_Name (D) = Name_Access
10949 and then Is_Class_Wide_Type (Etype (Prefix (D))));
10950 end Is_Class_Wide_Default;
10952 -- Start of processing for Process_Formals
10955 -- In order to prevent premature use of the formals in the same formal
10956 -- part, the Ekind is left undefined until all default expressions are
10957 -- analyzed. The Ekind is established in a separate loop at the end.
10959 Param_Spec := First (T);
10960 while Present (Param_Spec) loop
10961 Formal := Defining_Identifier (Param_Spec);
10962 Set_Never_Set_In_Source (Formal, True);
10963 Enter_Name (Formal);
10965 -- Case of ordinary parameters
10967 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
10968 Find_Type (Parameter_Type (Param_Spec));
10969 Ptype := Parameter_Type (Param_Spec);
10971 if Ptype = Error then
10975 Formal_Type := Entity (Ptype);
10977 if Is_Incomplete_Type (Formal_Type)
10979 (Is_Class_Wide_Type (Formal_Type)
10980 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
10982 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
10983 -- primitive operations, as long as their completion is
10984 -- in the same declarative part. If in the private part
10985 -- this means that the type cannot be a Taft-amendment type.
10986 -- Check is done on package exit. For access to subprograms,
10987 -- the use is legal for Taft-amendment types.
10989 -- Ada 2012: tagged incomplete types are allowed as generic
10990 -- formal types. They do not introduce dependencies and the
10991 -- corresponding generic subprogram does not have a delayed
10992 -- freeze, because it does not need a freeze node.
10994 if Is_Tagged_Type (Formal_Type) then
10995 if Ekind (Scope (Current_Scope)) = E_Package
10996 and then not From_With_Type (Formal_Type)
10997 and then not Is_Generic_Type (Formal_Type)
10998 and then not Is_Class_Wide_Type (Formal_Type)
11001 (Parent (T), N_Access_Function_Definition,
11002 N_Access_Procedure_Definition)
11006 Private_Dependents (Base_Type (Formal_Type)));
11008 -- Freezing is delayed to ensure that Register_Prim
11009 -- will get called for this operation, which is needed
11010 -- in cases where static dispatch tables aren't built.
11011 -- (Note that the same is done for controlling access
11012 -- parameter cases in function Access_Definition.)
11014 Set_Has_Delayed_Freeze (Current_Scope);
11018 -- Special handling of Value_Type for CIL case
11020 elsif Is_Value_Type (Formal_Type) then
11023 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
11024 N_Access_Procedure_Definition)
11026 -- AI05-0151: Tagged incomplete types are allowed in all
11027 -- formal parts. Untagged incomplete types are not allowed
11030 if Ada_Version >= Ada_2012 then
11031 if Is_Tagged_Type (Formal_Type) then
11034 elsif Nkind_In (Parent (Parent (T)), N_Accept_Statement,
11039 ("invalid use of untagged incomplete type&",
11040 Ptype, Formal_Type);
11045 ("invalid use of incomplete type&",
11046 Param_Spec, Formal_Type);
11048 -- Further checks on the legality of incomplete types
11049 -- in formal parts are delayed until the freeze point
11050 -- of the enclosing subprogram or access to subprogram.
11054 elsif Ekind (Formal_Type) = E_Void then
11056 ("premature use of&",
11057 Parameter_Type (Param_Spec), Formal_Type);
11060 -- Ada 2012 (AI-142): Handle aliased parameters
11062 if Ada_Version >= Ada_2012
11063 and then Aliased_Present (Param_Spec)
11065 Set_Is_Aliased (Formal);
11068 -- Ada 2005 (AI-231): Create and decorate an internal subtype
11069 -- declaration corresponding to the null-excluding type of the
11070 -- formal in the enclosing scope. Finally, replace the parameter
11071 -- type of the formal with the internal subtype.
11073 if Ada_Version >= Ada_2005
11074 and then Null_Exclusion_Present (Param_Spec)
11076 if not Is_Access_Type (Formal_Type) then
11078 ("`NOT NULL` allowed only for an access type", Param_Spec);
11081 if Can_Never_Be_Null (Formal_Type)
11082 and then Comes_From_Source (Related_Nod)
11085 ("`NOT NULL` not allowed (& already excludes null)",
11086 Param_Spec, Formal_Type);
11090 Create_Null_Excluding_Itype
11092 Related_Nod => Related_Nod,
11093 Scope_Id => Scope (Current_Scope));
11095 -- If the designated type of the itype is an itype that is
11096 -- not frozen yet, we set the Has_Delayed_Freeze attribute
11097 -- on the access subtype, to prevent order-of-elaboration
11098 -- issues in the backend.
11101 -- type T is access procedure;
11102 -- procedure Op (O : not null T);
11104 if Is_Itype (Directly_Designated_Type (Formal_Type))
11106 not Is_Frozen (Directly_Designated_Type (Formal_Type))
11108 Set_Has_Delayed_Freeze (Formal_Type);
11113 -- An access formal type
11117 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
11119 -- No need to continue if we already notified errors
11121 if not Present (Formal_Type) then
11125 -- Ada 2005 (AI-254)
11128 AD : constant Node_Id :=
11129 Access_To_Subprogram_Definition
11130 (Parameter_Type (Param_Spec));
11132 if Present (AD) and then Protected_Present (AD) then
11134 Replace_Anonymous_Access_To_Protected_Subprogram
11140 Set_Etype (Formal, Formal_Type);
11142 -- Deal with default expression if present
11144 Default := Expression (Param_Spec);
11146 if Present (Default) then
11147 Check_SPARK_Restriction
11148 ("default expression is not allowed", Default);
11150 if Out_Present (Param_Spec) then
11152 ("default initialization only allowed for IN parameters",
11156 -- Do the special preanalysis of the expression (see section on
11157 -- "Handling of Default Expressions" in the spec of package Sem).
11159 Preanalyze_Spec_Expression (Default, Formal_Type);
11161 -- An access to constant cannot be the default for
11162 -- an access parameter that is an access to variable.
11164 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11165 and then not Is_Access_Constant (Formal_Type)
11166 and then Is_Access_Type (Etype (Default))
11167 and then Is_Access_Constant (Etype (Default))
11170 ("formal that is access to variable cannot be initialized " &
11171 "with an access-to-constant expression", Default);
11174 -- Check that the designated type of an access parameter's default
11175 -- is not a class-wide type unless the parameter's designated type
11176 -- is also class-wide.
11178 if Ekind (Formal_Type) = E_Anonymous_Access_Type
11179 and then not Designates_From_With_Type (Formal_Type)
11180 and then Is_Class_Wide_Default (Default)
11181 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
11184 ("access to class-wide expression not allowed here", Default);
11187 -- Check incorrect use of dynamically tagged expressions
11189 if Is_Tagged_Type (Formal_Type) then
11190 Check_Dynamically_Tagged_Expression
11192 Typ => Formal_Type,
11193 Related_Nod => Default);
11197 -- Ada 2005 (AI-231): Static checks
11199 if Ada_Version >= Ada_2005
11200 and then Is_Access_Type (Etype (Formal))
11201 and then Can_Never_Be_Null (Etype (Formal))
11203 Null_Exclusion_Static_Checks (Param_Spec);
11210 -- If this is the formal part of a function specification, analyze the
11211 -- subtype mark in the context where the formals are visible but not
11212 -- yet usable, and may hide outer homographs.
11214 if Nkind (Related_Nod) = N_Function_Specification then
11215 Analyze_Return_Type (Related_Nod);
11218 -- Now set the kind (mode) of each formal
11220 Param_Spec := First (T);
11221 while Present (Param_Spec) loop
11222 Formal := Defining_Identifier (Param_Spec);
11223 Set_Formal_Mode (Formal);
11225 if Ekind (Formal) = E_In_Parameter then
11226 Set_Default_Value (Formal, Expression (Param_Spec));
11228 if Present (Expression (Param_Spec)) then
11229 Default := Expression (Param_Spec);
11231 if Is_Scalar_Type (Etype (Default)) then
11232 if Nkind (Parameter_Type (Param_Spec)) /=
11233 N_Access_Definition
11235 Formal_Type := Entity (Parameter_Type (Param_Spec));
11239 (Related_Nod, Parameter_Type (Param_Spec));
11242 Apply_Scalar_Range_Check (Default, Formal_Type);
11246 elsif Ekind (Formal) = E_Out_Parameter then
11247 Num_Out_Params := Num_Out_Params + 1;
11249 if Num_Out_Params = 1 then
11250 First_Out_Param := Formal;
11253 elsif Ekind (Formal) = E_In_Out_Parameter then
11254 Num_Out_Params := Num_Out_Params + 1;
11257 -- Skip remaining processing if formal type was in error
11259 if Etype (Formal) = Any_Type or else Error_Posted (Formal) then
11260 goto Next_Parameter;
11263 -- Force call by reference if aliased
11265 if Is_Aliased (Formal) then
11266 Set_Mechanism (Formal, By_Reference);
11268 -- Warn if user asked this to be passed by copy
11270 if Convention (Formal_Type) = Convention_Ada_Pass_By_Copy then
11272 ("cannot pass aliased parameter & by copy?", Formal);
11275 -- Force mechanism if type has Convention Ada_Pass_By_Ref/Copy
11277 elsif Convention (Formal_Type) = Convention_Ada_Pass_By_Copy then
11278 Set_Mechanism (Formal, By_Copy);
11280 elsif Convention (Formal_Type) = Convention_Ada_Pass_By_Reference then
11281 Set_Mechanism (Formal, By_Reference);
11288 if Present (First_Out_Param) and then Num_Out_Params = 1 then
11289 Set_Is_Only_Out_Parameter (First_Out_Param);
11291 end Process_Formals;
11293 ----------------------------
11294 -- Reference_Body_Formals --
11295 ----------------------------
11297 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
11302 if Error_Posted (Spec) then
11306 -- Iterate over both lists. They may be of different lengths if the two
11307 -- specs are not conformant.
11309 Fs := First_Formal (Spec);
11310 Fb := First_Formal (Bod);
11311 while Present (Fs) and then Present (Fb) loop
11312 Generate_Reference (Fs, Fb, 'b');
11314 if Style_Check then
11315 Style.Check_Identifier (Fb, Fs);
11318 Set_Spec_Entity (Fb, Fs);
11319 Set_Referenced (Fs, False);
11323 end Reference_Body_Formals;
11325 -------------------------
11326 -- Set_Actual_Subtypes --
11327 -------------------------
11329 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
11331 Formal : Entity_Id;
11333 First_Stmt : Node_Id := Empty;
11334 AS_Needed : Boolean;
11337 -- If this is an empty initialization procedure, no need to create
11338 -- actual subtypes (small optimization).
11340 if Ekind (Subp) = E_Procedure and then Is_Null_Init_Proc (Subp) then
11344 Formal := First_Formal (Subp);
11345 while Present (Formal) loop
11346 T := Etype (Formal);
11348 -- We never need an actual subtype for a constrained formal
11350 if Is_Constrained (T) then
11351 AS_Needed := False;
11353 -- If we have unknown discriminants, then we do not need an actual
11354 -- subtype, or more accurately we cannot figure it out! Note that
11355 -- all class-wide types have unknown discriminants.
11357 elsif Has_Unknown_Discriminants (T) then
11358 AS_Needed := False;
11360 -- At this stage we have an unconstrained type that may need an
11361 -- actual subtype. For sure the actual subtype is needed if we have
11362 -- an unconstrained array type.
11364 elsif Is_Array_Type (T) then
11367 -- The only other case needing an actual subtype is an unconstrained
11368 -- record type which is an IN parameter (we cannot generate actual
11369 -- subtypes for the OUT or IN OUT case, since an assignment can
11370 -- change the discriminant values. However we exclude the case of
11371 -- initialization procedures, since discriminants are handled very
11372 -- specially in this context, see the section entitled "Handling of
11373 -- Discriminants" in Einfo.
11375 -- We also exclude the case of Discrim_SO_Functions (functions used
11376 -- in front end layout mode for size/offset values), since in such
11377 -- functions only discriminants are referenced, and not only are such
11378 -- subtypes not needed, but they cannot always be generated, because
11379 -- of order of elaboration issues.
11381 elsif Is_Record_Type (T)
11382 and then Ekind (Formal) = E_In_Parameter
11383 and then Chars (Formal) /= Name_uInit
11384 and then not Is_Unchecked_Union (T)
11385 and then not Is_Discrim_SO_Function (Subp)
11389 -- All other cases do not need an actual subtype
11392 AS_Needed := False;
11395 -- Generate actual subtypes for unconstrained arrays and
11396 -- unconstrained discriminated records.
11399 if Nkind (N) = N_Accept_Statement then
11401 -- If expansion is active, the formal is replaced by a local
11402 -- variable that renames the corresponding entry of the
11403 -- parameter block, and it is this local variable that may
11404 -- require an actual subtype.
11406 if Full_Expander_Active then
11407 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
11409 Decl := Build_Actual_Subtype (T, Formal);
11412 if Present (Handled_Statement_Sequence (N)) then
11414 First (Statements (Handled_Statement_Sequence (N)));
11415 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
11416 Mark_Rewrite_Insertion (Decl);
11418 -- If the accept statement has no body, there will be no
11419 -- reference to the actuals, so no need to compute actual
11426 Decl := Build_Actual_Subtype (T, Formal);
11427 Prepend (Decl, Declarations (N));
11428 Mark_Rewrite_Insertion (Decl);
11431 -- The declaration uses the bounds of an existing object, and
11432 -- therefore needs no constraint checks.
11434 Analyze (Decl, Suppress => All_Checks);
11436 -- We need to freeze manually the generated type when it is
11437 -- inserted anywhere else than in a declarative part.
11439 if Present (First_Stmt) then
11440 Insert_List_Before_And_Analyze (First_Stmt,
11441 Freeze_Entity (Defining_Identifier (Decl), N));
11444 if Nkind (N) = N_Accept_Statement
11445 and then Full_Expander_Active
11447 Set_Actual_Subtype (Renamed_Object (Formal),
11448 Defining_Identifier (Decl));
11450 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
11454 Next_Formal (Formal);
11456 end Set_Actual_Subtypes;
11458 ---------------------
11459 -- Set_Formal_Mode --
11460 ---------------------
11462 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
11463 Spec : constant Node_Id := Parent (Formal_Id);
11466 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
11467 -- since we ensure that corresponding actuals are always valid at the
11468 -- point of the call.
11470 if Out_Present (Spec) then
11471 if Ekind (Scope (Formal_Id)) = E_Function
11472 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
11474 -- [IN] OUT parameters allowed for functions in Ada 2012
11476 if Ada_Version >= Ada_2012 then
11478 -- Even in Ada 2012 operators can only have IN parameters
11480 if Is_Operator_Symbol_Name (Chars (Scope (Formal_Id))) then
11481 Error_Msg_N ("operators can only have IN parameters", Spec);
11484 if In_Present (Spec) then
11485 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11487 Set_Ekind (Formal_Id, E_Out_Parameter);
11490 -- But not in earlier versions of Ada
11493 Error_Msg_N ("functions can only have IN parameters", Spec);
11494 Set_Ekind (Formal_Id, E_In_Parameter);
11497 elsif In_Present (Spec) then
11498 Set_Ekind (Formal_Id, E_In_Out_Parameter);
11501 Set_Ekind (Formal_Id, E_Out_Parameter);
11502 Set_Never_Set_In_Source (Formal_Id, True);
11503 Set_Is_True_Constant (Formal_Id, False);
11504 Set_Current_Value (Formal_Id, Empty);
11508 Set_Ekind (Formal_Id, E_In_Parameter);
11511 -- Set Is_Known_Non_Null for access parameters since the language
11512 -- guarantees that access parameters are always non-null. We also set
11513 -- Can_Never_Be_Null, since there is no way to change the value.
11515 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
11517 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
11518 -- null; In Ada 2005, only if then null_exclusion is explicit.
11520 if Ada_Version < Ada_2005
11521 or else Can_Never_Be_Null (Etype (Formal_Id))
11523 Set_Is_Known_Non_Null (Formal_Id);
11524 Set_Can_Never_Be_Null (Formal_Id);
11527 -- Ada 2005 (AI-231): Null-exclusion access subtype
11529 elsif Is_Access_Type (Etype (Formal_Id))
11530 and then Can_Never_Be_Null (Etype (Formal_Id))
11532 Set_Is_Known_Non_Null (Formal_Id);
11534 -- We can also set Can_Never_Be_Null (thus preventing some junk
11535 -- access checks) for the case of an IN parameter, which cannot
11536 -- be changed, or for an IN OUT parameter, which can be changed but
11537 -- not to a null value. But for an OUT parameter, the initial value
11538 -- passed in can be null, so we can't set this flag in that case.
11540 if Ekind (Formal_Id) /= E_Out_Parameter then
11541 Set_Can_Never_Be_Null (Formal_Id);
11545 Set_Mechanism (Formal_Id, Default_Mechanism);
11546 Set_Formal_Validity (Formal_Id);
11547 end Set_Formal_Mode;
11549 -------------------------
11550 -- Set_Formal_Validity --
11551 -------------------------
11553 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
11555 -- If no validity checking, then we cannot assume anything about the
11556 -- validity of parameters, since we do not know there is any checking
11557 -- of the validity on the call side.
11559 if not Validity_Checks_On then
11562 -- If validity checking for parameters is enabled, this means we are
11563 -- not supposed to make any assumptions about argument values.
11565 elsif Validity_Check_Parameters then
11568 -- If we are checking in parameters, we will assume that the caller is
11569 -- also checking parameters, so we can assume the parameter is valid.
11571 elsif Ekind (Formal_Id) = E_In_Parameter
11572 and then Validity_Check_In_Params
11574 Set_Is_Known_Valid (Formal_Id, True);
11576 -- Similar treatment for IN OUT parameters
11578 elsif Ekind (Formal_Id) = E_In_Out_Parameter
11579 and then Validity_Check_In_Out_Params
11581 Set_Is_Known_Valid (Formal_Id, True);
11583 end Set_Formal_Validity;
11585 ------------------------
11586 -- Subtype_Conformant --
11587 ------------------------
11589 function Subtype_Conformant
11590 (New_Id : Entity_Id;
11591 Old_Id : Entity_Id;
11592 Skip_Controlling_Formals : Boolean := False) return Boolean
11596 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
11597 Skip_Controlling_Formals => Skip_Controlling_Formals);
11599 end Subtype_Conformant;
11601 ---------------------
11602 -- Type_Conformant --
11603 ---------------------
11605 function Type_Conformant
11606 (New_Id : Entity_Id;
11607 Old_Id : Entity_Id;
11608 Skip_Controlling_Formals : Boolean := False) return Boolean
11612 May_Hide_Profile := False;
11615 (New_Id, Old_Id, Type_Conformant, False, Result,
11616 Skip_Controlling_Formals => Skip_Controlling_Formals);
11618 end Type_Conformant;
11620 -------------------------------
11621 -- Valid_Operator_Definition --
11622 -------------------------------
11624 procedure Valid_Operator_Definition (Designator : Entity_Id) is
11627 Id : constant Name_Id := Chars (Designator);
11631 F := First_Formal (Designator);
11632 while Present (F) loop
11635 if Present (Default_Value (F)) then
11637 ("default values not allowed for operator parameters",
11644 -- Verify that user-defined operators have proper number of arguments
11645 -- First case of operators which can only be unary
11647 if Nam_In (Id, Name_Op_Not, Name_Op_Abs) then
11650 -- Case of operators which can be unary or binary
11652 elsif Nam_In (Id, Name_Op_Add, Name_Op_Subtract) then
11653 N_OK := (N in 1 .. 2);
11655 -- All other operators can only be binary
11663 ("incorrect number of arguments for operator", Designator);
11667 and then Base_Type (Etype (Designator)) = Standard_Boolean
11668 and then not Is_Intrinsic_Subprogram (Designator)
11671 ("explicit definition of inequality not allowed", Designator);
11673 end Valid_Operator_Definition;