1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, 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 Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Ch7; use Exp_Ch7;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Lib.Xref; use Lib.Xref;
43 with Layout; use Layout;
44 with Namet; use Namet;
46 with Nlists; use Nlists;
47 with Nmake; use Nmake;
49 with Output; use Output;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Cat; use Sem_Cat;
56 with Sem_Ch3; use Sem_Ch3;
57 with Sem_Ch4; use Sem_Ch4;
58 with Sem_Ch5; use Sem_Ch5;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch10; use Sem_Ch10;
61 with Sem_Ch12; use Sem_Ch12;
62 with Sem_Ch13; use Sem_Ch13;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Prag; use Sem_Prag;
69 with Sem_Res; use Sem_Res;
70 with Sem_Util; use Sem_Util;
71 with Sem_Type; use Sem_Type;
72 with Sem_Warn; use Sem_Warn;
73 with Sinput; use Sinput;
74 with Stand; use Stand;
75 with Sinfo; use Sinfo;
76 with Sinfo.CN; use Sinfo.CN;
77 with Snames; use Snames;
78 with Stringt; use Stringt;
80 with Stylesw; use Stylesw;
81 with Tbuild; use Tbuild;
82 with Uintp; use Uintp;
83 with Urealp; use Urealp;
84 with Validsw; use Validsw;
86 package body Sem_Ch6 is
88 May_Hide_Profile : Boolean := False;
89 -- This flag is used to indicate that two formals in two subprograms being
90 -- checked for conformance differ only in that one is an access parameter
91 -- while the other is of a general access type with the same designated
92 -- type. In this case, if the rest of the signatures match, a call to
93 -- either subprogram may be ambiguous, which is worth a warning. The flag
94 -- is set in Compatible_Types, and the warning emitted in
95 -- New_Overloaded_Entity.
97 -----------------------
98 -- Local Subprograms --
99 -----------------------
101 procedure Analyze_Return_Statement (N : Node_Id);
102 -- Common processing for simple and extended return statements
104 procedure Analyze_Function_Return (N : Node_Id);
105 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
106 -- applies to a [generic] function.
108 procedure Analyze_Return_Type (N : Node_Id);
109 -- Subsidiary to Process_Formals: analyze subtype mark in function
110 -- specification in a context where the formals are visible and hide
113 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
114 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
115 -- that we can use RETURN but not skip the debug output at the end.
117 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
118 -- Analyze a generic subprogram body. N is the body to be analyzed, and
119 -- Gen_Id is the defining entity Id for the corresponding spec.
121 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
122 -- If a subprogram has pragma Inline and inlining is active, use generic
123 -- machinery to build an unexpanded body for the subprogram. This body is
124 -- subsequently used for inline expansions at call sites. If subprogram can
125 -- be inlined (depending on size and nature of local declarations) this
126 -- function returns true. Otherwise subprogram body is treated normally.
127 -- If proper warnings are enabled and the subprogram contains a construct
128 -- that cannot be inlined, the offending construct is flagged accordingly.
130 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
131 -- Returns true if Subp can override a predefined operator.
133 procedure Check_Conformance
136 Ctype : Conformance_Type;
138 Conforms : out Boolean;
139 Err_Loc : Node_Id := Empty;
140 Get_Inst : Boolean := False;
141 Skip_Controlling_Formals : Boolean := False);
142 -- Given two entities, this procedure checks that the profiles associated
143 -- with these entities meet the conformance criterion given by the third
144 -- parameter. If they conform, Conforms is set True and control returns
145 -- to the caller. If they do not conform, Conforms is set to False, and
146 -- in addition, if Errmsg is True on the call, proper messages are output
147 -- to complain about the conformance failure. If Err_Loc is non_Empty
148 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
149 -- error messages are placed on the appropriate part of the construct
150 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
151 -- against a formal access-to-subprogram type so Get_Instance_Of must
154 procedure Check_Subprogram_Order (N : Node_Id);
155 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
156 -- the alpha ordering rule for N if this ordering requirement applicable.
158 procedure Check_Returns
162 Proc : Entity_Id := Empty);
163 -- Called to check for missing return statements in a function body, or for
164 -- returns present in a procedure body which has No_Return set. HSS is the
165 -- handled statement sequence for the subprogram body. This procedure
166 -- checks all flow paths to make sure they either have return (Mode = 'F',
167 -- used for functions) or do not have a return (Mode = 'P', used for
168 -- No_Return procedures). The flag Err is set if there are any control
169 -- paths not explicitly terminated by a return in the function case, and is
170 -- True otherwise. Proc is the entity for the procedure case and is used
171 -- in posting the warning message.
173 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
174 -- In Ada 2012, a primitive equality operator on an untagged record type
175 -- must appear before the type is frozen, and have the same visibility as
176 -- that of the type. This procedure checks that this rule is met, and
177 -- otherwise emits an error on the subprogram declaration and a warning
178 -- on the earlier freeze point if it is easy to locate.
180 procedure Enter_Overloaded_Entity (S : Entity_Id);
181 -- This procedure makes S, a new overloaded entity, into the first visible
182 -- entity with that name.
184 procedure Install_Entity (E : Entity_Id);
185 -- Make single entity visible (used for generic formals as well)
187 function Is_Non_Overriding_Operation
189 New_E : Entity_Id) return Boolean;
190 -- Enforce the rule given in 12.3(18): a private operation in an instance
191 -- overrides an inherited operation only if the corresponding operation
192 -- was overriding in the generic. This can happen for primitive operations
193 -- of types derived (in the generic unit) from formal private or formal
196 procedure Make_Inequality_Operator (S : Entity_Id);
197 -- Create the declaration for an inequality operator that is implicitly
198 -- created by a user-defined equality operator that yields a boolean.
200 procedure May_Need_Actuals (Fun : Entity_Id);
201 -- Flag functions that can be called without parameters, i.e. those that
202 -- have no parameters, or those for which defaults exist for all parameters
204 procedure Process_PPCs
207 Body_Id : Entity_Id);
208 -- Called from Analyze[_Generic]_Subprogram_Body to deal with scanning post
209 -- conditions for the body and assembling and inserting the _postconditions
210 -- procedure. N is the node for the subprogram body and Body_Id/Spec_Id are
211 -- the entities for the body and separate spec (if there is no separate
212 -- spec, Spec_Id is Empty). Note that invariants and predicates may also
213 -- provide postconditions, and are also handled in this procedure.
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", 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 Def_Id : constant Entity_Id := Defining_Entity (Specification (N));
277 Prev : constant Entity_Id := Current_Entity_In_Scope (Def_Id);
278 -- If the expression is a completion, Prev is the entity whose
279 -- declaration is completed.
282 -- This is one of the occasions on which we transform the tree during
283 -- semantic analysis. If this is a completion, transform the expression
284 -- function into an equivalent subprogram body, and analyze it.
286 -- Expression functions are inlined unconditionally. The back-end will
287 -- determine whether this is possible.
289 Inline_Processing_Required := True;
292 Make_Subprogram_Body (Loc,
293 Specification => Specification (N),
294 Declarations => Empty_List,
295 Handled_Statement_Sequence =>
296 Make_Handled_Sequence_Of_Statements (LocX,
297 Statements => New_List (
298 Make_Simple_Return_Statement (LocX,
299 Expression => Expression (N)))));
302 and then Ekind (Prev) = E_Generic_Function
304 -- If the expression completes a generic subprogram, we must create a
305 -- separate node for the body, because at instantiation the original
306 -- node of the generic copy must be a generic subprogram body, and
307 -- cannot be a expression function. Otherwise we just rewrite the
308 -- expression with the non-generic body.
310 Insert_After (N, New_Body);
311 Rewrite (N, Make_Null_Statement (Loc));
314 Set_Is_Inlined (Prev);
316 elsif Present (Prev) then
317 Rewrite (N, New_Body);
318 Set_Is_Inlined (Prev);
321 -- If this is not a completion, create both a declaration and a body,
322 -- so that the expression can be inlined whenever possible.
326 Make_Subprogram_Declaration (Loc,
327 Specification => Specification (N));
328 Rewrite (N, New_Decl);
330 Set_Is_Inlined (Defining_Entity (New_Decl));
332 -- Create new set of formals for specification in body.
334 Set_Specification (New_Body,
335 Make_Function_Specification (Loc,
336 Defining_Unit_Name =>
337 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))),
338 Parameter_Specifications =>
339 Copy_Parameter_List (Defining_Entity (New_Decl)),
341 New_Copy_Tree (Result_Definition (Specification (New_Decl)))));
343 Insert_After (N, New_Body);
346 end Analyze_Expression_Function;
348 ----------------------------------------
349 -- Analyze_Extended_Return_Statement --
350 ----------------------------------------
352 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
354 Analyze_Return_Statement (N);
355 end Analyze_Extended_Return_Statement;
357 ----------------------------
358 -- Analyze_Function_Call --
359 ----------------------------
361 procedure Analyze_Function_Call (N : Node_Id) is
362 P : constant Node_Id := Name (N);
363 Actuals : constant List_Id := Parameter_Associations (N);
369 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
370 -- as B (A, X). If the rewriting is successful, the call has been
371 -- analyzed and we just return.
373 if Nkind (P) = N_Selected_Component
374 and then Name (N) /= P
375 and then Is_Rewrite_Substitution (N)
376 and then Present (Etype (N))
381 -- If error analyzing name, then set Any_Type as result type and return
383 if Etype (P) = Any_Type then
384 Set_Etype (N, Any_Type);
388 -- Otherwise analyze the parameters
390 if Present (Actuals) then
391 Actual := First (Actuals);
392 while Present (Actual) loop
394 Check_Parameterless_Call (Actual);
400 end Analyze_Function_Call;
402 -----------------------------
403 -- Analyze_Function_Return --
404 -----------------------------
406 procedure Analyze_Function_Return (N : Node_Id) is
407 Loc : constant Source_Ptr := Sloc (N);
408 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
409 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
411 R_Type : constant Entity_Id := Etype (Scope_Id);
412 -- Function result subtype
414 procedure Check_Limited_Return (Expr : Node_Id);
415 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
416 -- limited types. Used only for simple return statements.
417 -- Expr is the expression returned.
419 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
420 -- Check that the return_subtype_indication properly matches the result
421 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
423 --------------------------
424 -- Check_Limited_Return --
425 --------------------------
427 procedure Check_Limited_Return (Expr : Node_Id) is
429 -- Ada 2005 (AI-318-02): Return-by-reference types have been
430 -- removed and replaced by anonymous access results. This is an
431 -- incompatibility with Ada 95. Not clear whether this should be
432 -- enforced yet or perhaps controllable with special switch. ???
434 if Is_Limited_Type (R_Type)
435 and then Comes_From_Source (N)
436 and then not In_Instance_Body
437 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
441 if Ada_Version >= Ada_2005
442 and then not Debug_Flag_Dot_L
443 and then not GNAT_Mode
446 ("(Ada 2005) cannot copy object of a limited type " &
447 "(RM-2005 6.5(5.5/2))", Expr);
449 if Is_Immutably_Limited_Type (R_Type) then
451 ("\return by reference not permitted in Ada 2005", Expr);
454 -- Warn in Ada 95 mode, to give folks a heads up about this
457 -- In GNAT mode, this is just a warning, to allow it to be
458 -- evilly turned off. Otherwise it is a real error.
460 -- In a generic context, simplify the warning because it makes
461 -- no sense to discuss pass-by-reference or copy.
463 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
464 if Inside_A_Generic then
466 ("return of limited object not permitted in Ada2005 "
467 & "(RM-2005 6.5(5.5/2))?", Expr);
469 elsif Is_Immutably_Limited_Type (R_Type) then
471 ("return by reference not permitted in Ada 2005 "
472 & "(RM-2005 6.5(5.5/2))?", Expr);
475 ("cannot copy object of a limited type in Ada 2005 "
476 & "(RM-2005 6.5(5.5/2))?", Expr);
479 -- Ada 95 mode, compatibility warnings disabled
482 return; -- skip continuation messages below
485 if not Inside_A_Generic then
487 ("\consider switching to return of access type", Expr);
488 Explain_Limited_Type (R_Type, Expr);
491 end Check_Limited_Return;
493 -------------------------------------
494 -- Check_Return_Subtype_Indication --
495 -------------------------------------
497 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
498 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
500 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
501 -- Subtype given in the extended return statement (must match R_Type)
503 Subtype_Ind : constant Node_Id :=
504 Object_Definition (Original_Node (Obj_Decl));
506 R_Type_Is_Anon_Access :
508 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
510 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
512 Ekind (R_Type) = E_Anonymous_Access_Type;
513 -- True if return type of the function is an anonymous access type
514 -- Can't we make Is_Anonymous_Access_Type in einfo ???
516 R_Stm_Type_Is_Anon_Access :
518 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
520 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
522 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
523 -- True if type of the return object is an anonymous access type
526 -- First, avoid cascaded errors
528 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
532 -- "return access T" case; check that the return statement also has
533 -- "access T", and that the subtypes statically match:
534 -- if this is an access to subprogram the signatures must match.
536 if R_Type_Is_Anon_Access then
537 if R_Stm_Type_Is_Anon_Access then
539 Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
541 if Base_Type (Designated_Type (R_Stm_Type)) /=
542 Base_Type (Designated_Type (R_Type))
543 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
546 ("subtype must statically match function result subtype",
547 Subtype_Mark (Subtype_Ind));
551 -- For two anonymous access to subprogram types, the
552 -- types themselves must be type conformant.
554 if not Conforming_Types
555 (R_Stm_Type, R_Type, Fully_Conformant)
558 ("subtype must statically match function result subtype",
564 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
567 -- If the return object is of an anonymous access type, then report
568 -- an error if the function's result type is not also anonymous.
570 elsif R_Stm_Type_Is_Anon_Access
571 and then not R_Type_Is_Anon_Access
573 Error_Msg_N ("anonymous access not allowed for function with " &
574 "named access result", Subtype_Ind);
576 -- Subtype indication case: check that the return object's type is
577 -- covered by the result type, and that the subtypes statically match
578 -- when the result subtype is constrained. Also handle record types
579 -- with unknown discriminants for which we have built the underlying
580 -- record view. Coverage is needed to allow specific-type return
581 -- objects when the result type is class-wide (see AI05-32).
583 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
584 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
588 Underlying_Record_View (Base_Type (R_Stm_Type))))
590 -- A null exclusion may be present on the return type, on the
591 -- function specification, on the object declaration or on the
594 if Is_Access_Type (R_Type)
596 (Can_Never_Be_Null (R_Type)
597 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
598 Can_Never_Be_Null (R_Stm_Type)
601 ("subtype must statically match function result subtype",
605 -- AI05-103: for elementary types, subtypes must statically match
607 if Is_Constrained (R_Type)
608 or else Is_Access_Type (R_Type)
610 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
612 ("subtype must statically match function result subtype",
617 elsif Etype (Base_Type (R_Type)) = R_Stm_Type
618 and then Is_Null_Extension (Base_Type (R_Type))
624 ("wrong type for return_subtype_indication", Subtype_Ind);
626 end Check_Return_Subtype_Indication;
628 ---------------------
629 -- Local Variables --
630 ---------------------
634 -- Start of processing for Analyze_Function_Return
637 Set_Return_Present (Scope_Id);
639 if Nkind (N) = N_Simple_Return_Statement then
640 Expr := Expression (N);
642 -- Guard against a malformed expression. The parser may have tried to
643 -- recover but the node is not analyzable.
645 if Nkind (Expr) = N_Error then
646 Set_Etype (Expr, Any_Type);
647 Expander_Mode_Save_And_Set (False);
651 -- The resolution of a controlled [extension] aggregate associated
652 -- with a return statement creates a temporary which needs to be
653 -- finalized on function exit. Wrap the return statement inside a
654 -- block so that the finalization machinery can detect this case.
655 -- This early expansion is done only when the return statement is
656 -- not part of a handled sequence of statements.
658 if Nkind_In (Expr, N_Aggregate,
659 N_Extension_Aggregate)
660 and then Needs_Finalization (R_Type)
661 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
664 Make_Block_Statement (Loc,
665 Handled_Statement_Sequence =>
666 Make_Handled_Sequence_Of_Statements (Loc,
667 Statements => New_List (Relocate_Node (N)))));
673 Analyze_And_Resolve (Expr, R_Type);
674 Check_Limited_Return (Expr);
677 -- RETURN only allowed in SPARK as the last statement in function
679 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
681 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
682 or else Present (Next (N)))
684 Check_SPARK_Restriction
685 ("RETURN should be the last statement in function", N);
689 Check_SPARK_Restriction ("extended RETURN is not allowed", N);
691 -- Analyze parts specific to extended_return_statement:
694 Obj_Decl : constant Node_Id :=
695 Last (Return_Object_Declarations (N));
697 HSS : constant Node_Id := Handled_Statement_Sequence (N);
700 Expr := Expression (Obj_Decl);
702 -- Note: The check for OK_For_Limited_Init will happen in
703 -- Analyze_Object_Declaration; we treat it as a normal
704 -- object declaration.
706 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
709 Check_Return_Subtype_Indication (Obj_Decl);
711 if Present (HSS) then
714 if Present (Exception_Handlers (HSS)) then
716 -- ???Has_Nested_Block_With_Handler needs to be set.
717 -- Probably by creating an actual N_Block_Statement.
718 -- Probably in Expand.
724 -- Mark the return object as referenced, since the return is an
725 -- implicit reference of the object.
727 Set_Referenced (Defining_Identifier (Obj_Decl));
729 Check_References (Stm_Entity);
733 -- Case of Expr present
737 -- Defend against previous errors
739 and then Nkind (Expr) /= N_Empty
740 and then Present (Etype (Expr))
742 -- Apply constraint check. Note that this is done before the implicit
743 -- conversion of the expression done for anonymous access types to
744 -- ensure correct generation of the null-excluding check associated
745 -- with null-excluding expressions found in return statements.
747 Apply_Constraint_Check (Expr, R_Type);
749 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
750 -- type, apply an implicit conversion of the expression to that type
751 -- to force appropriate static and run-time accessibility checks.
753 if Ada_Version >= Ada_2005
754 and then Ekind (R_Type) = E_Anonymous_Access_Type
756 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
757 Analyze_And_Resolve (Expr, R_Type);
760 -- If the result type is class-wide, then check that the return
761 -- expression's type is not declared at a deeper level than the
762 -- function (RM05-6.5(5.6/2)).
764 if Ada_Version >= Ada_2005
765 and then Is_Class_Wide_Type (R_Type)
767 if Type_Access_Level (Etype (Expr)) >
768 Subprogram_Access_Level (Scope_Id)
771 ("level of return expression type is deeper than " &
772 "class-wide function!", Expr);
776 -- Check incorrect use of dynamically tagged expression
778 if Is_Tagged_Type (R_Type) then
779 Check_Dynamically_Tagged_Expression
785 -- ??? A real run-time accessibility check is needed in cases
786 -- involving dereferences of access parameters. For now we just
787 -- check the static cases.
789 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
790 and then Is_Immutably_Limited_Type (Etype (Scope_Id))
791 and then Object_Access_Level (Expr) >
792 Subprogram_Access_Level (Scope_Id)
795 -- Suppress the message in a generic, where the rewriting
798 if Inside_A_Generic then
803 Make_Raise_Program_Error (Loc,
804 Reason => PE_Accessibility_Check_Failed));
808 ("cannot return a local value by reference?", N);
810 ("\& will be raised at run time?",
811 N, Standard_Program_Error);
816 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
817 and then Null_Exclusion_Present (Parent (Scope_Id))
819 Apply_Compile_Time_Constraint_Error
821 Msg => "(Ada 2005) null not allowed for "
822 & "null-excluding return?",
823 Reason => CE_Null_Not_Allowed);
826 -- Apply checks suggested by AI05-0144 (dangerous order dependence)
828 Check_Order_Dependence;
830 end Analyze_Function_Return;
832 -------------------------------------
833 -- Analyze_Generic_Subprogram_Body --
834 -------------------------------------
836 procedure Analyze_Generic_Subprogram_Body
840 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
841 Kind : constant Entity_Kind := Ekind (Gen_Id);
847 -- Copy body and disable expansion while analyzing the generic For a
848 -- stub, do not copy the stub (which would load the proper body), this
849 -- will be done when the proper body is analyzed.
851 if Nkind (N) /= N_Subprogram_Body_Stub then
852 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
857 Spec := Specification (N);
859 -- Within the body of the generic, the subprogram is callable, and
860 -- behaves like the corresponding non-generic unit.
862 Body_Id := Defining_Entity (Spec);
864 if Kind = E_Generic_Procedure
865 and then Nkind (Spec) /= N_Procedure_Specification
867 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
870 elsif Kind = E_Generic_Function
871 and then Nkind (Spec) /= N_Function_Specification
873 Error_Msg_N ("invalid body for generic function ", Body_Id);
877 Set_Corresponding_Body (Gen_Decl, Body_Id);
879 if Has_Completion (Gen_Id)
880 and then Nkind (Parent (N)) /= N_Subunit
882 Error_Msg_N ("duplicate generic body", N);
885 Set_Has_Completion (Gen_Id);
888 if Nkind (N) = N_Subprogram_Body_Stub then
889 Set_Ekind (Defining_Entity (Specification (N)), Kind);
891 Set_Corresponding_Spec (N, Gen_Id);
894 if Nkind (Parent (N)) = N_Compilation_Unit then
895 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
898 -- Make generic parameters immediately visible in the body. They are
899 -- needed to process the formals declarations. Then make the formals
900 -- visible in a separate step.
906 First_Ent : Entity_Id;
909 First_Ent := First_Entity (Gen_Id);
912 while Present (E) and then not Is_Formal (E) loop
917 Set_Use (Generic_Formal_Declarations (Gen_Decl));
919 -- Now generic formals are visible, and the specification can be
920 -- analyzed, for subsequent conformance check.
922 Body_Id := Analyze_Subprogram_Specification (Spec);
924 -- Make formal parameters visible
928 -- E is the first formal parameter, we loop through the formals
929 -- installing them so that they will be visible.
931 Set_First_Entity (Gen_Id, E);
932 while Present (E) loop
938 -- Visible generic entity is callable within its own body
940 Set_Ekind (Gen_Id, Ekind (Body_Id));
941 Set_Ekind (Body_Id, E_Subprogram_Body);
942 Set_Convention (Body_Id, Convention (Gen_Id));
943 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
944 Set_Scope (Body_Id, Scope (Gen_Id));
945 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
947 if Nkind (N) = N_Subprogram_Body_Stub then
949 -- No body to analyze, so restore state of generic unit
951 Set_Ekind (Gen_Id, Kind);
952 Set_Ekind (Body_Id, Kind);
954 if Present (First_Ent) then
955 Set_First_Entity (Gen_Id, First_Ent);
962 -- If this is a compilation unit, it must be made visible explicitly,
963 -- because the compilation of the declaration, unlike other library
964 -- unit declarations, does not. If it is not a unit, the following
965 -- is redundant but harmless.
967 Set_Is_Immediately_Visible (Gen_Id);
968 Reference_Body_Formals (Gen_Id, Body_Id);
970 if Is_Child_Unit (Gen_Id) then
971 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
974 Set_Actual_Subtypes (N, Current_Scope);
976 -- Deal with preconditions and postconditions. In formal verification
977 -- mode, we keep pre- and postconditions attached to entities rather
978 -- than inserted in the code, in order to facilitate a distinct
979 -- treatment for them.
981 if not Alfa_Mode then
982 Process_PPCs (N, Gen_Id, Body_Id);
985 -- If the generic unit carries pre- or post-conditions, copy them
986 -- to the original generic tree, so that they are properly added
987 -- to any instantiation.
990 Orig : constant Node_Id := Original_Node (N);
994 Cond := First (Declarations (N));
995 while Present (Cond) loop
996 if Nkind (Cond) = N_Pragma
997 and then Pragma_Name (Cond) = Name_Check
999 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1001 elsif Nkind (Cond) = N_Pragma
1002 and then Pragma_Name (Cond) = Name_Postcondition
1004 Set_Ekind (Defining_Entity (Orig), Ekind (Gen_Id));
1005 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1014 Analyze_Declarations (Declarations (N));
1016 Analyze (Handled_Statement_Sequence (N));
1018 Save_Global_References (Original_Node (N));
1020 -- Prior to exiting the scope, include generic formals again (if any
1021 -- are present) in the set of local entities.
1023 if Present (First_Ent) then
1024 Set_First_Entity (Gen_Id, First_Ent);
1027 Check_References (Gen_Id);
1030 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1032 Check_Subprogram_Order (N);
1034 -- Outside of its body, unit is generic again
1036 Set_Ekind (Gen_Id, Kind);
1037 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1040 Style.Check_Identifier (Body_Id, Gen_Id);
1044 end Analyze_Generic_Subprogram_Body;
1046 -----------------------------
1047 -- Analyze_Operator_Symbol --
1048 -----------------------------
1050 -- An operator symbol such as "+" or "and" may appear in context where the
1051 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1052 -- is just a string, as in (conjunction = "or"). In these cases the parser
1053 -- generates this node, and the semantics does the disambiguation. Other
1054 -- such case are actuals in an instantiation, the generic unit in an
1055 -- instantiation, and pragma arguments.
1057 procedure Analyze_Operator_Symbol (N : Node_Id) is
1058 Par : constant Node_Id := Parent (N);
1061 if (Nkind (Par) = N_Function_Call
1062 and then N = Name (Par))
1063 or else Nkind (Par) = N_Function_Instantiation
1064 or else (Nkind (Par) = N_Indexed_Component
1065 and then N = Prefix (Par))
1066 or else (Nkind (Par) = N_Pragma_Argument_Association
1067 and then not Is_Pragma_String_Literal (Par))
1068 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1069 or else (Nkind (Par) = N_Attribute_Reference
1070 and then Attribute_Name (Par) /= Name_Value)
1072 Find_Direct_Name (N);
1075 Change_Operator_Symbol_To_String_Literal (N);
1078 end Analyze_Operator_Symbol;
1080 -----------------------------------
1081 -- Analyze_Parameter_Association --
1082 -----------------------------------
1084 procedure Analyze_Parameter_Association (N : Node_Id) is
1086 Analyze (Explicit_Actual_Parameter (N));
1087 end Analyze_Parameter_Association;
1089 ----------------------------
1090 -- Analyze_Procedure_Call --
1091 ----------------------------
1093 procedure Analyze_Procedure_Call (N : Node_Id) is
1094 Loc : constant Source_Ptr := Sloc (N);
1095 P : constant Node_Id := Name (N);
1096 Actuals : constant List_Id := Parameter_Associations (N);
1100 procedure Analyze_Call_And_Resolve;
1101 -- Do Analyze and Resolve calls for procedure call
1102 -- At end, check illegal order dependence.
1104 ------------------------------
1105 -- Analyze_Call_And_Resolve --
1106 ------------------------------
1108 procedure Analyze_Call_And_Resolve is
1110 if Nkind (N) = N_Procedure_Call_Statement then
1112 Resolve (N, Standard_Void_Type);
1114 -- Apply checks suggested by AI05-0144
1116 Check_Order_Dependence;
1121 end Analyze_Call_And_Resolve;
1123 -- Start of processing for Analyze_Procedure_Call
1126 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1127 -- a procedure call or an entry call. The prefix may denote an access
1128 -- to subprogram type, in which case an implicit dereference applies.
1129 -- If the prefix is an indexed component (without implicit dereference)
1130 -- then the construct denotes a call to a member of an entire family.
1131 -- If the prefix is a simple name, it may still denote a call to a
1132 -- parameterless member of an entry family. Resolution of these various
1133 -- interpretations is delicate.
1137 -- If this is a call of the form Obj.Op, the call may have been
1138 -- analyzed and possibly rewritten into a block, in which case
1141 if Analyzed (N) then
1145 -- If there is an error analyzing the name (which may have been
1146 -- rewritten if the original call was in prefix notation) then error
1147 -- has been emitted already, mark node and return.
1150 or else Etype (Name (N)) = Any_Type
1152 Set_Etype (N, Any_Type);
1156 -- Otherwise analyze the parameters
1158 if Present (Actuals) then
1159 Actual := First (Actuals);
1161 while Present (Actual) loop
1163 Check_Parameterless_Call (Actual);
1168 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1170 if Nkind (P) = N_Attribute_Reference
1171 and then (Attribute_Name (P) = Name_Elab_Spec
1172 or else Attribute_Name (P) = Name_Elab_Body
1173 or else Attribute_Name (P) = Name_Elab_Subp_Body)
1175 if Present (Actuals) then
1177 ("no parameters allowed for this call", First (Actuals));
1181 Set_Etype (N, Standard_Void_Type);
1184 elsif Is_Entity_Name (P)
1185 and then Is_Record_Type (Etype (Entity (P)))
1186 and then Remote_AST_I_Dereference (P)
1190 elsif Is_Entity_Name (P)
1191 and then Ekind (Entity (P)) /= E_Entry_Family
1193 if Is_Access_Type (Etype (P))
1194 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1195 and then No (Actuals)
1196 and then Comes_From_Source (N)
1198 Error_Msg_N ("missing explicit dereference in call", N);
1201 Analyze_Call_And_Resolve;
1203 -- If the prefix is the simple name of an entry family, this is
1204 -- a parameterless call from within the task body itself.
1206 elsif Is_Entity_Name (P)
1207 and then Nkind (P) = N_Identifier
1208 and then Ekind (Entity (P)) = E_Entry_Family
1209 and then Present (Actuals)
1210 and then No (Next (First (Actuals)))
1212 -- Can be call to parameterless entry family. What appears to be the
1213 -- sole argument is in fact the entry index. Rewrite prefix of node
1214 -- accordingly. Source representation is unchanged by this
1218 Make_Indexed_Component (Loc,
1220 Make_Selected_Component (Loc,
1221 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1222 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1223 Expressions => Actuals);
1224 Set_Name (N, New_N);
1225 Set_Etype (New_N, Standard_Void_Type);
1226 Set_Parameter_Associations (N, No_List);
1227 Analyze_Call_And_Resolve;
1229 elsif Nkind (P) = N_Explicit_Dereference then
1230 if Ekind (Etype (P)) = E_Subprogram_Type then
1231 Analyze_Call_And_Resolve;
1233 Error_Msg_N ("expect access to procedure in call", P);
1236 -- The name can be a selected component or an indexed component that
1237 -- yields an access to subprogram. Such a prefix is legal if the call
1238 -- has parameter associations.
1240 elsif Is_Access_Type (Etype (P))
1241 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1243 if Present (Actuals) then
1244 Analyze_Call_And_Resolve;
1246 Error_Msg_N ("missing explicit dereference in call ", N);
1249 -- If not an access to subprogram, then the prefix must resolve to the
1250 -- name of an entry, entry family, or protected operation.
1252 -- For the case of a simple entry call, P is a selected component where
1253 -- the prefix is the task and the selector name is the entry. A call to
1254 -- a protected procedure will have the same syntax. If the protected
1255 -- object contains overloaded operations, the entity may appear as a
1256 -- function, the context will select the operation whose type is Void.
1258 elsif Nkind (P) = N_Selected_Component
1259 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1261 Ekind (Entity (Selector_Name (P))) = E_Procedure
1263 Ekind (Entity (Selector_Name (P))) = E_Function)
1265 Analyze_Call_And_Resolve;
1267 elsif Nkind (P) = N_Selected_Component
1268 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1269 and then Present (Actuals)
1270 and then No (Next (First (Actuals)))
1272 -- Can be call to parameterless entry family. What appears to be the
1273 -- sole argument is in fact the entry index. Rewrite prefix of node
1274 -- accordingly. Source representation is unchanged by this
1278 Make_Indexed_Component (Loc,
1279 Prefix => New_Copy (P),
1280 Expressions => Actuals);
1281 Set_Name (N, New_N);
1282 Set_Etype (New_N, Standard_Void_Type);
1283 Set_Parameter_Associations (N, No_List);
1284 Analyze_Call_And_Resolve;
1286 -- For the case of a reference to an element of an entry family, P is
1287 -- an indexed component whose prefix is a selected component (task and
1288 -- entry family), and whose index is the entry family index.
1290 elsif Nkind (P) = N_Indexed_Component
1291 and then Nkind (Prefix (P)) = N_Selected_Component
1292 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1294 Analyze_Call_And_Resolve;
1296 -- If the prefix is the name of an entry family, it is a call from
1297 -- within the task body itself.
1299 elsif Nkind (P) = N_Indexed_Component
1300 and then Nkind (Prefix (P)) = N_Identifier
1301 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1304 Make_Selected_Component (Loc,
1305 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1306 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1307 Rewrite (Prefix (P), New_N);
1309 Analyze_Call_And_Resolve;
1311 -- Anything else is an error
1314 Error_Msg_N ("invalid procedure or entry call", N);
1316 end Analyze_Procedure_Call;
1318 ------------------------------
1319 -- Analyze_Return_Statement --
1320 ------------------------------
1322 procedure Analyze_Return_Statement (N : Node_Id) is
1324 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
1325 N_Extended_Return_Statement));
1327 Returns_Object : constant Boolean :=
1328 Nkind (N) = N_Extended_Return_Statement
1330 (Nkind (N) = N_Simple_Return_Statement
1331 and then Present (Expression (N)));
1332 -- True if we're returning something; that is, "return <expression>;"
1333 -- or "return Result : T [:= ...]". False for "return;". Used for error
1334 -- checking: If Returns_Object is True, N should apply to a function
1335 -- body; otherwise N should apply to a procedure body, entry body,
1336 -- accept statement, or extended return statement.
1338 function Find_What_It_Applies_To return Entity_Id;
1339 -- Find the entity representing the innermost enclosing body, accept
1340 -- statement, or extended return statement. If the result is a callable
1341 -- construct or extended return statement, then this will be the value
1342 -- of the Return_Applies_To attribute. Otherwise, the program is
1343 -- illegal. See RM-6.5(4/2).
1345 -----------------------------
1346 -- Find_What_It_Applies_To --
1347 -----------------------------
1349 function Find_What_It_Applies_To return Entity_Id is
1350 Result : Entity_Id := Empty;
1353 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1354 -- and postconditions.
1356 for J in reverse 0 .. Scope_Stack.Last loop
1357 Result := Scope_Stack.Table (J).Entity;
1358 exit when not Ekind_In (Result, E_Block, E_Loop)
1359 and then Chars (Result) /= Name_uPostconditions;
1362 pragma Assert (Present (Result));
1364 end Find_What_It_Applies_To;
1366 -- Local declarations
1368 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1369 Kind : constant Entity_Kind := Ekind (Scope_Id);
1370 Loc : constant Source_Ptr := Sloc (N);
1371 Stm_Entity : constant Entity_Id :=
1373 (E_Return_Statement, Current_Scope, Loc, 'R');
1375 -- Start of processing for Analyze_Return_Statement
1378 Set_Return_Statement_Entity (N, Stm_Entity);
1380 Set_Etype (Stm_Entity, Standard_Void_Type);
1381 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1383 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1384 -- (4/2): an inner return statement will apply to this extended return.
1386 if Nkind (N) = N_Extended_Return_Statement then
1387 Push_Scope (Stm_Entity);
1390 -- Check that pragma No_Return is obeyed. Don't complain about the
1391 -- implicitly-generated return that is placed at the end.
1393 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1394 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1397 -- Warn on any unassigned OUT parameters if in procedure
1399 if Ekind (Scope_Id) = E_Procedure then
1400 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1403 -- Check that functions return objects, and other things do not
1405 if Kind = E_Function or else Kind = E_Generic_Function then
1406 if not Returns_Object then
1407 Error_Msg_N ("missing expression in return from function", N);
1410 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1411 if Returns_Object then
1412 Error_Msg_N ("procedure cannot return value (use function)", N);
1415 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1416 if Returns_Object then
1417 if Is_Protected_Type (Scope (Scope_Id)) then
1418 Error_Msg_N ("entry body cannot return value", N);
1420 Error_Msg_N ("accept statement cannot return value", N);
1424 elsif Kind = E_Return_Statement then
1426 -- We are nested within another return statement, which must be an
1427 -- extended_return_statement.
1429 if Returns_Object then
1431 ("extended_return_statement cannot return value; " &
1432 "use `""RETURN;""`", N);
1436 Error_Msg_N ("illegal context for return statement", N);
1439 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1440 Analyze_Function_Return (N);
1442 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1443 Set_Return_Present (Scope_Id);
1446 if Nkind (N) = N_Extended_Return_Statement then
1450 Kill_Current_Values (Last_Assignment_Only => True);
1451 Check_Unreachable_Code (N);
1452 end Analyze_Return_Statement;
1454 -------------------------------------
1455 -- Analyze_Simple_Return_Statement --
1456 -------------------------------------
1458 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1460 if Present (Expression (N)) then
1461 Mark_Coextensions (N, Expression (N));
1464 Analyze_Return_Statement (N);
1465 end Analyze_Simple_Return_Statement;
1467 -------------------------
1468 -- Analyze_Return_Type --
1469 -------------------------
1471 procedure Analyze_Return_Type (N : Node_Id) is
1472 Designator : constant Entity_Id := Defining_Entity (N);
1473 Typ : Entity_Id := Empty;
1476 -- Normal case where result definition does not indicate an error
1478 if Result_Definition (N) /= Error then
1479 if Nkind (Result_Definition (N)) = N_Access_Definition then
1480 Check_SPARK_Restriction
1481 ("access result is not allowed", Result_Definition (N));
1483 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1486 AD : constant Node_Id :=
1487 Access_To_Subprogram_Definition (Result_Definition (N));
1489 if Present (AD) and then Protected_Present (AD) then
1490 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1492 Typ := Access_Definition (N, Result_Definition (N));
1496 Set_Parent (Typ, Result_Definition (N));
1497 Set_Is_Local_Anonymous_Access (Typ);
1498 Set_Etype (Designator, Typ);
1500 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1502 Null_Exclusion_Static_Checks (N);
1504 -- Subtype_Mark case
1507 Find_Type (Result_Definition (N));
1508 Typ := Entity (Result_Definition (N));
1509 Set_Etype (Designator, Typ);
1511 -- Unconstrained array as result is not allowed in SPARK
1513 if Is_Array_Type (Typ)
1514 and then not Is_Constrained (Typ)
1516 Check_SPARK_Restriction
1517 ("returning an unconstrained array is not allowed",
1518 Result_Definition (N));
1521 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1523 Null_Exclusion_Static_Checks (N);
1525 -- If a null exclusion is imposed on the result type, then create
1526 -- a null-excluding itype (an access subtype) and use it as the
1527 -- function's Etype. Note that the null exclusion checks are done
1528 -- right before this, because they don't get applied to types that
1529 -- do not come from source.
1531 if Is_Access_Type (Typ)
1532 and then Null_Exclusion_Present (N)
1534 Set_Etype (Designator,
1535 Create_Null_Excluding_Itype
1538 Scope_Id => Scope (Current_Scope)));
1540 -- The new subtype must be elaborated before use because
1541 -- it is visible outside of the function. However its base
1542 -- type may not be frozen yet, so the reference that will
1543 -- force elaboration must be attached to the freezing of
1546 -- If the return specification appears on a proper body,
1547 -- the subtype will have been created already on the spec.
1549 if Is_Frozen (Typ) then
1550 if Nkind (Parent (N)) = N_Subprogram_Body
1551 and then Nkind (Parent (Parent (N))) = N_Subunit
1555 Build_Itype_Reference (Etype (Designator), Parent (N));
1559 Ensure_Freeze_Node (Typ);
1562 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
1564 Set_Itype (IR, Etype (Designator));
1565 Append_Freeze_Actions (Typ, New_List (IR));
1570 Set_Etype (Designator, Typ);
1573 if Ekind (Typ) = E_Incomplete_Type
1574 and then Is_Value_Type (Typ)
1578 elsif Ekind (Typ) = E_Incomplete_Type
1579 or else (Is_Class_Wide_Type (Typ)
1581 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1583 -- AI05-0151: Tagged incomplete types are allowed in all formal
1584 -- parts. Untagged incomplete types are not allowed in bodies.
1586 if Ada_Version >= Ada_2012 then
1587 if Is_Tagged_Type (Typ) then
1590 elsif Nkind_In (Parent (Parent (N)),
1596 ("invalid use of untagged incomplete type&",
1600 -- The type must be completed in the current package. This
1601 -- is checked at the end of the package declaraton, when
1602 -- Taft amemdment types are identified.
1604 if Ekind (Scope (Current_Scope)) = E_Package
1605 and then In_Private_Part (Scope (Current_Scope))
1607 Append_Elmt (Designator, Private_Dependents (Typ));
1612 ("invalid use of incomplete type&", Designator, Typ);
1617 -- Case where result definition does indicate an error
1620 Set_Etype (Designator, Any_Type);
1622 end Analyze_Return_Type;
1624 -----------------------------
1625 -- Analyze_Subprogram_Body --
1626 -----------------------------
1628 procedure Analyze_Subprogram_Body (N : Node_Id) is
1629 Loc : constant Source_Ptr := Sloc (N);
1630 Body_Spec : constant Node_Id := Specification (N);
1631 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
1634 if Debug_Flag_C then
1635 Write_Str ("==> subprogram body ");
1636 Write_Name (Chars (Body_Id));
1637 Write_Str (" from ");
1638 Write_Location (Loc);
1643 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1645 -- The real work is split out into the helper, so it can do "return;"
1646 -- without skipping the debug output:
1648 Analyze_Subprogram_Body_Helper (N);
1650 if Debug_Flag_C then
1652 Write_Str ("<== subprogram body ");
1653 Write_Name (Chars (Body_Id));
1654 Write_Str (" from ");
1655 Write_Location (Loc);
1658 end Analyze_Subprogram_Body;
1660 ------------------------------------
1661 -- Analyze_Subprogram_Body_Helper --
1662 ------------------------------------
1664 -- This procedure is called for regular subprogram bodies, generic bodies,
1665 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1666 -- specification matters, and is used to create a proper declaration for
1667 -- the subprogram, or to perform conformance checks.
1669 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
1670 Loc : constant Source_Ptr := Sloc (N);
1671 Body_Deleted : constant Boolean := False;
1672 Body_Spec : constant Node_Id := Specification (N);
1673 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1674 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1675 Conformant : Boolean;
1678 Prot_Typ : Entity_Id := Empty;
1679 Spec_Id : Entity_Id;
1680 Spec_Decl : Node_Id := Empty;
1682 Last_Real_Spec_Entity : Entity_Id := Empty;
1683 -- When we analyze a separate spec, the entity chain ends up containing
1684 -- the formals, as well as any itypes generated during analysis of the
1685 -- default expressions for parameters, or the arguments of associated
1686 -- precondition/postcondition pragmas (which are analyzed in the context
1687 -- of the spec since they have visibility on formals).
1689 -- These entities belong with the spec and not the body. However we do
1690 -- the analysis of the body in the context of the spec (again to obtain
1691 -- visibility to the formals), and all the entities generated during
1692 -- this analysis end up also chained to the entity chain of the spec.
1693 -- But they really belong to the body, and there is circuitry to move
1694 -- them from the spec to the body.
1696 -- However, when we do this move, we don't want to move the real spec
1697 -- entities (first para above) to the body. The Last_Real_Spec_Entity
1698 -- variable points to the last real spec entity, so we only move those
1699 -- chained beyond that point. It is initialized to Empty to deal with
1700 -- the case where there is no separate spec.
1702 procedure Check_Anonymous_Return;
1703 -- Ada 2005: if a function returns an access type that denotes a task,
1704 -- or a type that contains tasks, we must create a master entity for
1705 -- the anonymous type, which typically will be used in an allocator
1706 -- in the body of the function.
1708 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1709 -- Look ahead to recognize a pragma that may appear after the body.
1710 -- If there is a previous spec, check that it appears in the same
1711 -- declarative part. If the pragma is Inline_Always, perform inlining
1712 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1713 -- If the body acts as a spec, and inlining is required, we create a
1714 -- subprogram declaration for it, in order to attach the body to inline.
1715 -- If pragma does not appear after the body, check whether there is
1716 -- an inline pragma before any local declarations.
1718 procedure Check_Missing_Return;
1719 -- Checks for a function with a no return statements, and also performs
1720 -- the warning checks implemented by Check_Returns. In formal mode, also
1721 -- verify that a function ends with a RETURN and that a procedure does
1722 -- not contain any RETURN.
1724 function Disambiguate_Spec return Entity_Id;
1725 -- When a primitive is declared between the private view and the full
1726 -- view of a concurrent type which implements an interface, a special
1727 -- mechanism is used to find the corresponding spec of the primitive
1730 function Is_Private_Concurrent_Primitive
1731 (Subp_Id : Entity_Id) return Boolean;
1732 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
1733 -- type that implements an interface and has a private view.
1735 procedure Set_Trivial_Subprogram (N : Node_Id);
1736 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
1737 -- subprogram whose body is being analyzed. N is the statement node
1738 -- causing the flag to be set, if the following statement is a return
1739 -- of an entity, we mark the entity as set in source to suppress any
1740 -- warning on the stylized use of function stubs with a dummy return.
1742 procedure Verify_Overriding_Indicator;
1743 -- If there was a previous spec, the entity has been entered in the
1744 -- current scope previously. If the body itself carries an overriding
1745 -- indicator, check that it is consistent with the known status of the
1748 ----------------------------
1749 -- Check_Anonymous_Return --
1750 ----------------------------
1752 procedure Check_Anonymous_Return is
1758 if Present (Spec_Id) then
1764 if Ekind (Scop) = E_Function
1765 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1766 and then not Is_Thunk (Scop)
1767 and then (Has_Task (Designated_Type (Etype (Scop)))
1769 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
1771 Is_Limited_Record (Designated_Type (Etype (Scop)))))
1772 and then Expander_Active
1774 -- Avoid cases with no tasking support
1776 and then RTE_Available (RE_Current_Master)
1777 and then not Restriction_Active (No_Task_Hierarchy)
1780 Make_Object_Declaration (Loc,
1781 Defining_Identifier =>
1782 Make_Defining_Identifier (Loc, Name_uMaster),
1783 Constant_Present => True,
1784 Object_Definition =>
1785 New_Reference_To (RTE (RE_Master_Id), Loc),
1787 Make_Explicit_Dereference (Loc,
1788 New_Reference_To (RTE (RE_Current_Master), Loc)));
1790 if Present (Declarations (N)) then
1791 Prepend (Decl, Declarations (N));
1793 Set_Declarations (N, New_List (Decl));
1796 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1797 Set_Has_Master_Entity (Scop);
1799 -- Now mark the containing scope as a task master
1802 while Nkind (Par) /= N_Compilation_Unit loop
1803 Par := Parent (Par);
1804 pragma Assert (Present (Par));
1806 -- If we fall off the top, we are at the outer level, and
1807 -- the environment task is our effective master, so nothing
1811 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
1813 Set_Is_Task_Master (Par, True);
1818 end Check_Anonymous_Return;
1820 -------------------------
1821 -- Check_Inline_Pragma --
1822 -------------------------
1824 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1828 function Is_Inline_Pragma (N : Node_Id) return Boolean;
1829 -- True when N is a pragma Inline or Inline_Always that applies
1830 -- to this subprogram.
1832 -----------------------
1833 -- Is_Inline_Pragma --
1834 -----------------------
1836 function Is_Inline_Pragma (N : Node_Id) return Boolean is
1839 Nkind (N) = N_Pragma
1841 (Pragma_Name (N) = Name_Inline_Always
1844 and then Pragma_Name (N) = Name_Inline))
1847 (Expression (First (Pragma_Argument_Associations (N))))
1849 end Is_Inline_Pragma;
1851 -- Start of processing for Check_Inline_Pragma
1854 if not Expander_Active then
1858 if Is_List_Member (N)
1859 and then Present (Next (N))
1860 and then Is_Inline_Pragma (Next (N))
1864 elsif Nkind (N) /= N_Subprogram_Body_Stub
1865 and then Present (Declarations (N))
1866 and then Is_Inline_Pragma (First (Declarations (N)))
1868 Prag := First (Declarations (N));
1874 if Present (Prag) then
1875 if Present (Spec_Id) then
1876 if In_Same_List (N, Unit_Declaration_Node (Spec_Id)) then
1881 -- Create a subprogram declaration, to make treatment uniform
1884 Subp : constant Entity_Id :=
1885 Make_Defining_Identifier (Loc, Chars (Body_Id));
1886 Decl : constant Node_Id :=
1887 Make_Subprogram_Declaration (Loc,
1889 New_Copy_Tree (Specification (N)));
1892 Set_Defining_Unit_Name (Specification (Decl), Subp);
1894 if Present (First_Formal (Body_Id)) then
1895 Plist := Copy_Parameter_List (Body_Id);
1896 Set_Parameter_Specifications
1897 (Specification (Decl), Plist);
1900 Insert_Before (N, Decl);
1903 Set_Has_Pragma_Inline (Subp);
1905 if Pragma_Name (Prag) = Name_Inline_Always then
1906 Set_Is_Inlined (Subp);
1907 Set_Has_Pragma_Inline_Always (Subp);
1914 end Check_Inline_Pragma;
1916 --------------------------
1917 -- Check_Missing_Return --
1918 --------------------------
1920 procedure Check_Missing_Return is
1922 Missing_Ret : Boolean;
1925 if Nkind (Body_Spec) = N_Function_Specification then
1926 if Present (Spec_Id) then
1932 if Return_Present (Id) then
1933 Check_Returns (HSS, 'F', Missing_Ret);
1936 Set_Has_Missing_Return (Id);
1939 elsif (Is_Generic_Subprogram (Id)
1940 or else not Is_Machine_Code_Subprogram (Id))
1941 and then not Body_Deleted
1943 Error_Msg_N ("missing RETURN statement in function body", N);
1946 -- If procedure with No_Return, check returns
1948 elsif Nkind (Body_Spec) = N_Procedure_Specification
1949 and then Present (Spec_Id)
1950 and then No_Return (Spec_Id)
1952 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
1955 -- Special checks in SPARK mode
1957 if Nkind (Body_Spec) = N_Function_Specification then
1959 -- In SPARK mode, last statement of a function should be a return
1962 Stat : constant Node_Id := Last_Source_Statement (HSS);
1965 and then not Nkind_In (Stat, N_Simple_Return_Statement,
1966 N_Extended_Return_Statement)
1968 Check_SPARK_Restriction
1969 ("last statement in function should be RETURN", Stat);
1973 -- In SPARK mode, verify that a procedure has no return
1975 elsif Nkind (Body_Spec) = N_Procedure_Specification then
1976 if Present (Spec_Id) then
1982 -- Would be nice to point to return statement here, can we
1983 -- borrow the Check_Returns procedure here ???
1985 if Return_Present (Id) then
1986 Check_SPARK_Restriction
1987 ("procedure should not have RETURN", N);
1990 end Check_Missing_Return;
1992 -----------------------
1993 -- Disambiguate_Spec --
1994 -----------------------
1996 function Disambiguate_Spec return Entity_Id is
1997 Priv_Spec : Entity_Id;
2000 procedure Replace_Types (To_Corresponding : Boolean);
2001 -- Depending on the flag, replace the type of formal parameters of
2002 -- Body_Id if it is a concurrent type implementing interfaces with
2003 -- the corresponding record type or the other way around.
2005 procedure Replace_Types (To_Corresponding : Boolean) is
2007 Formal_Typ : Entity_Id;
2010 Formal := First_Formal (Body_Id);
2011 while Present (Formal) loop
2012 Formal_Typ := Etype (Formal);
2014 if Is_Class_Wide_Type (Formal_Typ) then
2015 Formal_Typ := Root_Type (Formal_Typ);
2018 -- From concurrent type to corresponding record
2020 if To_Corresponding then
2021 if Is_Concurrent_Type (Formal_Typ)
2022 and then Present (Corresponding_Record_Type (Formal_Typ))
2023 and then Present (Interfaces (
2024 Corresponding_Record_Type (Formal_Typ)))
2027 Corresponding_Record_Type (Formal_Typ));
2030 -- From corresponding record to concurrent type
2033 if Is_Concurrent_Record_Type (Formal_Typ)
2034 and then Present (Interfaces (Formal_Typ))
2037 Corresponding_Concurrent_Type (Formal_Typ));
2041 Next_Formal (Formal);
2045 -- Start of processing for Disambiguate_Spec
2048 -- Try to retrieve the specification of the body as is. All error
2049 -- messages are suppressed because the body may not have a spec in
2050 -- its current state.
2052 Spec_N := Find_Corresponding_Spec (N, False);
2054 -- It is possible that this is the body of a primitive declared
2055 -- between a private and a full view of a concurrent type. The
2056 -- controlling parameter of the spec carries the concurrent type,
2057 -- not the corresponding record type as transformed by Analyze_
2058 -- Subprogram_Specification. In such cases, we undo the change
2059 -- made by the analysis of the specification and try to find the
2062 -- Note that wrappers already have their corresponding specs and
2063 -- bodies set during their creation, so if the candidate spec is
2064 -- a wrapper, then we definitely need to swap all types to their
2065 -- original concurrent status.
2068 or else Is_Primitive_Wrapper (Spec_N)
2070 -- Restore all references of corresponding record types to the
2071 -- original concurrent types.
2073 Replace_Types (To_Corresponding => False);
2074 Priv_Spec := Find_Corresponding_Spec (N, False);
2076 -- The current body truly belongs to a primitive declared between
2077 -- a private and a full view. We leave the modified body as is,
2078 -- and return the true spec.
2080 if Present (Priv_Spec)
2081 and then Is_Private_Primitive (Priv_Spec)
2086 -- In case that this is some sort of error, restore the original
2087 -- state of the body.
2089 Replace_Types (To_Corresponding => True);
2093 end Disambiguate_Spec;
2095 -------------------------------------
2096 -- Is_Private_Concurrent_Primitive --
2097 -------------------------------------
2099 function Is_Private_Concurrent_Primitive
2100 (Subp_Id : Entity_Id) return Boolean
2102 Formal_Typ : Entity_Id;
2105 if Present (First_Formal (Subp_Id)) then
2106 Formal_Typ := Etype (First_Formal (Subp_Id));
2108 if Is_Concurrent_Record_Type (Formal_Typ) then
2109 if Is_Class_Wide_Type (Formal_Typ) then
2110 Formal_Typ := Root_Type (Formal_Typ);
2113 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
2116 -- The type of the first formal is a concurrent tagged type with
2120 Is_Concurrent_Type (Formal_Typ)
2121 and then Is_Tagged_Type (Formal_Typ)
2122 and then Has_Private_Declaration (Formal_Typ);
2126 end Is_Private_Concurrent_Primitive;
2128 ----------------------------
2129 -- Set_Trivial_Subprogram --
2130 ----------------------------
2132 procedure Set_Trivial_Subprogram (N : Node_Id) is
2133 Nxt : constant Node_Id := Next (N);
2136 Set_Is_Trivial_Subprogram (Body_Id);
2138 if Present (Spec_Id) then
2139 Set_Is_Trivial_Subprogram (Spec_Id);
2143 and then Nkind (Nxt) = N_Simple_Return_Statement
2144 and then No (Next (Nxt))
2145 and then Present (Expression (Nxt))
2146 and then Is_Entity_Name (Expression (Nxt))
2148 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
2150 end Set_Trivial_Subprogram;
2152 ---------------------------------
2153 -- Verify_Overriding_Indicator --
2154 ---------------------------------
2156 procedure Verify_Overriding_Indicator is
2158 if Must_Override (Body_Spec) then
2159 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
2160 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2164 elsif not Present (Overridden_Operation (Spec_Id)) then
2166 ("subprogram& is not overriding", Body_Spec, Spec_Id);
2169 elsif Must_Not_Override (Body_Spec) then
2170 if Present (Overridden_Operation (Spec_Id)) then
2172 ("subprogram& overrides inherited operation",
2173 Body_Spec, Spec_Id);
2175 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
2176 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2179 ("subprogram & overrides predefined operator ",
2180 Body_Spec, Spec_Id);
2182 -- If this is not a primitive operation or protected subprogram,
2183 -- then the overriding indicator is altogether illegal.
2185 elsif not Is_Primitive (Spec_Id)
2186 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
2189 ("overriding indicator only allowed " &
2190 "if subprogram is primitive",
2195 and then Present (Overridden_Operation (Spec_Id))
2197 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2198 Style.Missing_Overriding (N, Body_Id);
2201 and then Can_Override_Operator (Spec_Id)
2202 and then not Is_Predefined_File_Name
2203 (Unit_File_Name (Get_Source_Unit (Spec_Id)))
2205 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2206 Style.Missing_Overriding (N, Body_Id);
2208 end Verify_Overriding_Indicator;
2210 -- Start of processing for Analyze_Subprogram_Body_Helper
2213 -- Generic subprograms are handled separately. They always have a
2214 -- generic specification. Determine whether current scope has a
2215 -- previous declaration.
2217 -- If the subprogram body is defined within an instance of the same
2218 -- name, the instance appears as a package renaming, and will be hidden
2219 -- within the subprogram.
2221 if Present (Prev_Id)
2222 and then not Is_Overloadable (Prev_Id)
2223 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
2224 or else Comes_From_Source (Prev_Id))
2226 if Is_Generic_Subprogram (Prev_Id) then
2228 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2229 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2231 Analyze_Generic_Subprogram_Body (N, Spec_Id);
2233 if Nkind (N) = N_Subprogram_Body then
2234 HSS := Handled_Statement_Sequence (N);
2235 Check_Missing_Return;
2241 -- Previous entity conflicts with subprogram name. Attempting to
2242 -- enter name will post error.
2244 Enter_Name (Body_Id);
2248 -- Non-generic case, find the subprogram declaration, if one was seen,
2249 -- or enter new overloaded entity in the current scope. If the
2250 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
2251 -- part of the context of one of its subunits. No need to redo the
2254 elsif Prev_Id = Body_Id
2255 and then Has_Completion (Body_Id)
2260 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2262 if Nkind (N) = N_Subprogram_Body_Stub
2263 or else No (Corresponding_Spec (N))
2265 if Is_Private_Concurrent_Primitive (Body_Id) then
2266 Spec_Id := Disambiguate_Spec;
2268 Spec_Id := Find_Corresponding_Spec (N);
2271 -- If this is a duplicate body, no point in analyzing it
2273 if Error_Posted (N) then
2277 -- A subprogram body should cause freezing of its own declaration,
2278 -- but if there was no previous explicit declaration, then the
2279 -- subprogram will get frozen too late (there may be code within
2280 -- the body that depends on the subprogram having been frozen,
2281 -- such as uses of extra formals), so we force it to be frozen
2282 -- here. Same holds if the body and spec are compilation units.
2283 -- Finally, if the return type is an anonymous access to protected
2284 -- subprogram, it must be frozen before the body because its
2285 -- expansion has generated an equivalent type that is used when
2286 -- elaborating the body.
2288 if No (Spec_Id) then
2289 Freeze_Before (N, Body_Id);
2291 elsif Nkind (Parent (N)) = N_Compilation_Unit then
2292 Freeze_Before (N, Spec_Id);
2294 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
2295 Freeze_Before (N, Etype (Body_Id));
2299 Spec_Id := Corresponding_Spec (N);
2303 -- Do not inline any subprogram that contains nested subprograms, since
2304 -- the backend inlining circuit seems to generate uninitialized
2305 -- references in this case. We know this happens in the case of front
2306 -- end ZCX support, but it also appears it can happen in other cases as
2307 -- well. The backend often rejects attempts to inline in the case of
2308 -- nested procedures anyway, so little if anything is lost by this.
2309 -- Note that this is test is for the benefit of the back-end. There is
2310 -- a separate test for front-end inlining that also rejects nested
2313 -- Do not do this test if errors have been detected, because in some
2314 -- error cases, this code blows up, and we don't need it anyway if
2315 -- there have been errors, since we won't get to the linker anyway.
2317 if Comes_From_Source (Body_Id)
2318 and then Serious_Errors_Detected = 0
2322 P_Ent := Scope (P_Ent);
2323 exit when No (P_Ent) or else P_Ent = Standard_Standard;
2325 if Is_Subprogram (P_Ent) then
2326 Set_Is_Inlined (P_Ent, False);
2328 if Comes_From_Source (P_Ent)
2329 and then Has_Pragma_Inline (P_Ent)
2332 ("cannot inline& (nested subprogram)?",
2339 Check_Inline_Pragma (Spec_Id);
2341 -- Deal with special case of a fully private operation in the body of
2342 -- the protected type. We must create a declaration for the subprogram,
2343 -- in order to attach the protected subprogram that will be used in
2344 -- internal calls. We exclude compiler generated bodies from the
2345 -- expander since the issue does not arise for those cases.
2348 and then Comes_From_Source (N)
2349 and then Is_Protected_Type (Current_Scope)
2351 Spec_Id := Build_Private_Protected_Declaration (N);
2354 -- If a separate spec is present, then deal with freezing issues
2356 if Present (Spec_Id) then
2357 Spec_Decl := Unit_Declaration_Node (Spec_Id);
2358 Verify_Overriding_Indicator;
2360 -- In general, the spec will be frozen when we start analyzing the
2361 -- body. However, for internally generated operations, such as
2362 -- wrapper functions for inherited operations with controlling
2363 -- results, the spec may not have been frozen by the time we expand
2364 -- the freeze actions that include the bodies. In particular, extra
2365 -- formals for accessibility or for return-in-place may need to be
2366 -- generated. Freeze nodes, if any, are inserted before the current
2367 -- body. These freeze actions are also needed in ASIS mode to enable
2368 -- the proper back-annotations.
2370 if not Is_Frozen (Spec_Id)
2371 and then (Expander_Active or ASIS_Mode)
2373 -- Force the generation of its freezing node to ensure proper
2374 -- management of access types in the backend.
2376 -- This is definitely needed for some cases, but it is not clear
2377 -- why, to be investigated further???
2379 Set_Has_Delayed_Freeze (Spec_Id);
2380 Freeze_Before (N, Spec_Id);
2384 -- Mark presence of postcondition procedure in current scope and mark
2385 -- the procedure itself as needing debug info. The latter is important
2386 -- when analyzing decision coverage (for example, for MC/DC coverage).
2388 if Chars (Body_Id) = Name_uPostconditions then
2389 Set_Has_Postconditions (Current_Scope);
2390 Set_Debug_Info_Needed (Body_Id);
2393 -- Place subprogram on scope stack, and make formals visible. If there
2394 -- is a spec, the visible entity remains that of the spec.
2396 if Present (Spec_Id) then
2397 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
2399 if Is_Child_Unit (Spec_Id) then
2400 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
2404 Style.Check_Identifier (Body_Id, Spec_Id);
2407 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2408 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2410 if Is_Abstract_Subprogram (Spec_Id) then
2411 Error_Msg_N ("an abstract subprogram cannot have a body", N);
2415 Set_Convention (Body_Id, Convention (Spec_Id));
2416 Set_Has_Completion (Spec_Id);
2418 if Is_Protected_Type (Scope (Spec_Id)) then
2419 Prot_Typ := Scope (Spec_Id);
2422 -- If this is a body generated for a renaming, do not check for
2423 -- full conformance. The check is redundant, because the spec of
2424 -- the body is a copy of the spec in the renaming declaration,
2425 -- and the test can lead to spurious errors on nested defaults.
2427 if Present (Spec_Decl)
2428 and then not Comes_From_Source (N)
2430 (Nkind (Original_Node (Spec_Decl)) =
2431 N_Subprogram_Renaming_Declaration
2432 or else (Present (Corresponding_Body (Spec_Decl))
2434 Nkind (Unit_Declaration_Node
2435 (Corresponding_Body (Spec_Decl))) =
2436 N_Subprogram_Renaming_Declaration))
2440 -- Conversely, the spec may have been generated for specless body
2441 -- with an inline pragma.
2443 elsif Comes_From_Source (N)
2444 and then not Comes_From_Source (Spec_Id)
2445 and then Has_Pragma_Inline (Spec_Id)
2452 Fully_Conformant, True, Conformant, Body_Id);
2455 -- If the body is not fully conformant, we have to decide if we
2456 -- should analyze it or not. If it has a really messed up profile
2457 -- then we probably should not analyze it, since we will get too
2458 -- many bogus messages.
2460 -- Our decision is to go ahead in the non-fully conformant case
2461 -- only if it is at least mode conformant with the spec. Note
2462 -- that the call to Check_Fully_Conformant has issued the proper
2463 -- error messages to complain about the lack of conformance.
2466 and then not Mode_Conformant (Body_Id, Spec_Id)
2472 if Spec_Id /= Body_Id then
2473 Reference_Body_Formals (Spec_Id, Body_Id);
2476 if Nkind (N) /= N_Subprogram_Body_Stub then
2477 Set_Corresponding_Spec (N, Spec_Id);
2479 -- Ada 2005 (AI-345): If the operation is a primitive operation
2480 -- of a concurrent type, the type of the first parameter has been
2481 -- replaced with the corresponding record, which is the proper
2482 -- run-time structure to use. However, within the body there may
2483 -- be uses of the formals that depend on primitive operations
2484 -- of the type (in particular calls in prefixed form) for which
2485 -- we need the original concurrent type. The operation may have
2486 -- several controlling formals, so the replacement must be done
2489 if Comes_From_Source (Spec_Id)
2490 and then Present (First_Entity (Spec_Id))
2491 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2492 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2494 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2497 (Corresponding_Concurrent_Type
2498 (Etype (First_Entity (Spec_Id))))
2501 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2505 Form := First_Formal (Spec_Id);
2506 while Present (Form) loop
2507 if Etype (Form) = Typ then
2508 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2516 -- Make the formals visible, and place subprogram on scope stack.
2517 -- This is also the point at which we set Last_Real_Spec_Entity
2518 -- to mark the entities which will not be moved to the body.
2520 Install_Formals (Spec_Id);
2521 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2522 Push_Scope (Spec_Id);
2524 -- Make sure that the subprogram is immediately visible. For
2525 -- child units that have no separate spec this is indispensable.
2526 -- Otherwise it is safe albeit redundant.
2528 Set_Is_Immediately_Visible (Spec_Id);
2531 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2532 Set_Ekind (Body_Id, E_Subprogram_Body);
2533 Set_Scope (Body_Id, Scope (Spec_Id));
2534 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2536 -- Case of subprogram body with no previous spec
2539 -- Check for style warning required
2543 -- Only apply check for source level subprograms for which checks
2544 -- have not been suppressed.
2546 and then Comes_From_Source (Body_Id)
2547 and then not Suppress_Style_Checks (Body_Id)
2549 -- No warnings within an instance
2551 and then not In_Instance
2553 -- No warnings for expression functions
2555 and then Nkind (Original_Node (N)) /= N_Expression_Function
2557 Style.Body_With_No_Spec (N);
2560 New_Overloaded_Entity (Body_Id);
2562 if Nkind (N) /= N_Subprogram_Body_Stub then
2563 Set_Acts_As_Spec (N);
2564 Generate_Definition (Body_Id);
2565 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
2567 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2568 Install_Formals (Body_Id);
2569 Push_Scope (Body_Id);
2572 -- For stubs and bodies with no previous spec, generate references to
2575 Generate_Reference_To_Formals (Body_Id);
2578 -- If the return type is an anonymous access type whose designated type
2579 -- is the limited view of a class-wide type and the non-limited view is
2580 -- available, update the return type accordingly.
2582 if Ada_Version >= Ada_2005
2583 and then Comes_From_Source (N)
2590 Rtyp := Etype (Current_Scope);
2592 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2593 Etyp := Directly_Designated_Type (Rtyp);
2595 if Is_Class_Wide_Type (Etyp)
2596 and then From_With_Type (Etyp)
2598 Set_Directly_Designated_Type
2599 (Etype (Current_Scope), Available_View (Etyp));
2605 -- If this is the proper body of a stub, we must verify that the stub
2606 -- conforms to the body, and to the previous spec if one was present.
2607 -- We know already that the body conforms to that spec. This test is
2608 -- only required for subprograms that come from source.
2610 if Nkind (Parent (N)) = N_Subunit
2611 and then Comes_From_Source (N)
2612 and then not Error_Posted (Body_Id)
2613 and then Nkind (Corresponding_Stub (Parent (N))) =
2614 N_Subprogram_Body_Stub
2617 Old_Id : constant Entity_Id :=
2619 (Specification (Corresponding_Stub (Parent (N))));
2621 Conformant : Boolean := False;
2624 if No (Spec_Id) then
2625 Check_Fully_Conformant (Body_Id, Old_Id);
2629 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2631 if not Conformant then
2633 -- The stub was taken to be a new declaration. Indicate that
2636 Set_Has_Completion (Old_Id, False);
2642 Set_Has_Completion (Body_Id);
2643 Check_Eliminated (Body_Id);
2645 if Nkind (N) = N_Subprogram_Body_Stub then
2648 elsif Present (Spec_Id)
2649 and then Expander_Active
2651 (Has_Pragma_Inline_Always (Spec_Id)
2652 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2654 Build_Body_To_Inline (N, Spec_Id);
2657 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2658 -- of the specification we have to install the private withed units.
2659 -- This holds for child units as well.
2661 if Is_Compilation_Unit (Body_Id)
2662 or else Nkind (Parent (N)) = N_Compilation_Unit
2664 Install_Private_With_Clauses (Body_Id);
2667 Check_Anonymous_Return;
2669 -- Set the Protected_Formal field of each extra formal of the protected
2670 -- subprogram to reference the corresponding extra formal of the
2671 -- subprogram that implements it. For regular formals this occurs when
2672 -- the protected subprogram's declaration is expanded, but the extra
2673 -- formals don't get created until the subprogram is frozen. We need to
2674 -- do this before analyzing the protected subprogram's body so that any
2675 -- references to the original subprogram's extra formals will be changed
2676 -- refer to the implementing subprogram's formals (see Expand_Formal).
2678 if Present (Spec_Id)
2679 and then Is_Protected_Type (Scope (Spec_Id))
2680 and then Present (Protected_Body_Subprogram (Spec_Id))
2683 Impl_Subp : constant Entity_Id :=
2684 Protected_Body_Subprogram (Spec_Id);
2685 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2686 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2688 while Present (Prot_Ext_Formal) loop
2689 pragma Assert (Present (Impl_Ext_Formal));
2690 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2691 Next_Formal_With_Extras (Prot_Ext_Formal);
2692 Next_Formal_With_Extras (Impl_Ext_Formal);
2697 -- Now we can go on to analyze the body
2699 HSS := Handled_Statement_Sequence (N);
2700 Set_Actual_Subtypes (N, Current_Scope);
2702 -- Deal with preconditions and postconditions. In formal verification
2703 -- mode, we keep pre- and postconditions attached to entities rather
2704 -- than inserted in the code, in order to facilitate a distinct
2705 -- treatment for them.
2707 if not Alfa_Mode then
2708 Process_PPCs (N, Spec_Id, Body_Id);
2711 -- Add a declaration for the Protection object, renaming declarations
2712 -- for discriminals and privals and finally a declaration for the entry
2713 -- family index (if applicable). This form of early expansion is done
2714 -- when the Expander is active because Install_Private_Data_Declarations
2715 -- references entities which were created during regular expansion.
2717 if Full_Expander_Active
2718 and then Comes_From_Source (N)
2719 and then Present (Prot_Typ)
2720 and then Present (Spec_Id)
2721 and then not Is_Eliminated (Spec_Id)
2723 Install_Private_Data_Declarations
2724 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2727 -- Analyze the declarations (this call will analyze the precondition
2728 -- Check pragmas we prepended to the list, as well as the declaration
2729 -- of the _Postconditions procedure).
2731 Analyze_Declarations (Declarations (N));
2733 -- Check completion, and analyze the statements
2736 Inspect_Deferred_Constant_Completion (Declarations (N));
2739 -- Deal with end of scope processing for the body
2741 Process_End_Label (HSS, 't', Current_Scope);
2743 Check_Subprogram_Order (N);
2744 Set_Analyzed (Body_Id);
2746 -- If we have a separate spec, then the analysis of the declarations
2747 -- caused the entities in the body to be chained to the spec id, but
2748 -- we want them chained to the body id. Only the formal parameters
2749 -- end up chained to the spec id in this case.
2751 if Present (Spec_Id) then
2753 -- We must conform to the categorization of our spec
2755 Validate_Categorization_Dependency (N, Spec_Id);
2757 -- And if this is a child unit, the parent units must conform
2759 if Is_Child_Unit (Spec_Id) then
2760 Validate_Categorization_Dependency
2761 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2764 -- Here is where we move entities from the spec to the body
2766 -- Case where there are entities that stay with the spec
2768 if Present (Last_Real_Spec_Entity) then
2770 -- No body entities (happens when the only real spec entities come
2771 -- from precondition and postcondition pragmas).
2773 if No (Last_Entity (Body_Id)) then
2775 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2777 -- Body entities present (formals), so chain stuff past them
2781 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2784 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2785 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2786 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2788 -- Case where there are no spec entities, in this case there can be
2789 -- no body entities either, so just move everything.
2792 pragma Assert (No (Last_Entity (Body_Id)));
2793 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2794 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2795 Set_First_Entity (Spec_Id, Empty);
2796 Set_Last_Entity (Spec_Id, Empty);
2800 Check_Missing_Return;
2802 -- Now we are going to check for variables that are never modified in
2803 -- the body of the procedure. But first we deal with a special case
2804 -- where we want to modify this check. If the body of the subprogram
2805 -- starts with a raise statement or its equivalent, or if the body
2806 -- consists entirely of a null statement, then it is pretty obvious
2807 -- that it is OK to not reference the parameters. For example, this
2808 -- might be the following common idiom for a stubbed function:
2809 -- statement of the procedure raises an exception. In particular this
2810 -- deals with the common idiom of a stubbed function, which might
2811 -- appear as something like:
2813 -- function F (A : Integer) return Some_Type;
2816 -- raise Program_Error;
2820 -- Here the purpose of X is simply to satisfy the annoying requirement
2821 -- in Ada that there be at least one return, and we certainly do not
2822 -- want to go posting warnings on X that it is not initialized! On
2823 -- the other hand, if X is entirely unreferenced that should still
2826 -- What we do is to detect these cases, and if we find them, flag the
2827 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2828 -- suppress unwanted warnings. For the case of the function stub above
2829 -- we have a special test to set X as apparently assigned to suppress
2836 -- Skip initial labels (for one thing this occurs when we are in
2837 -- front end ZCX mode, but in any case it is irrelevant), and also
2838 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2840 Stm := First (Statements (HSS));
2841 while Nkind (Stm) = N_Label
2842 or else Nkind (Stm) in N_Push_xxx_Label
2847 -- Do the test on the original statement before expansion
2850 Ostm : constant Node_Id := Original_Node (Stm);
2853 -- If explicit raise statement, turn on flag
2855 if Nkind (Ostm) = N_Raise_Statement then
2856 Set_Trivial_Subprogram (Stm);
2858 -- If null statement, and no following statements, turn on flag
2860 elsif Nkind (Stm) = N_Null_Statement
2861 and then Comes_From_Source (Stm)
2862 and then No (Next (Stm))
2864 Set_Trivial_Subprogram (Stm);
2866 -- Check for explicit call cases which likely raise an exception
2868 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2869 if Is_Entity_Name (Name (Ostm)) then
2871 Ent : constant Entity_Id := Entity (Name (Ostm));
2874 -- If the procedure is marked No_Return, then likely it
2875 -- raises an exception, but in any case it is not coming
2876 -- back here, so turn on the flag.
2879 and then Ekind (Ent) = E_Procedure
2880 and then No_Return (Ent)
2882 Set_Trivial_Subprogram (Stm);
2890 -- Check for variables that are never modified
2896 -- If there is a separate spec, then transfer Never_Set_In_Source
2897 -- flags from out parameters to the corresponding entities in the
2898 -- body. The reason we do that is we want to post error flags on
2899 -- the body entities, not the spec entities.
2901 if Present (Spec_Id) then
2902 E1 := First_Entity (Spec_Id);
2903 while Present (E1) loop
2904 if Ekind (E1) = E_Out_Parameter then
2905 E2 := First_Entity (Body_Id);
2906 while Present (E2) loop
2907 exit when Chars (E1) = Chars (E2);
2911 if Present (E2) then
2912 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2920 -- Check references in body unless it was deleted. Note that the
2921 -- check of Body_Deleted here is not just for efficiency, it is
2922 -- necessary to avoid junk warnings on formal parameters.
2924 if not Body_Deleted then
2925 Check_References (Body_Id);
2928 end Analyze_Subprogram_Body_Helper;
2930 ------------------------------------
2931 -- Analyze_Subprogram_Declaration --
2932 ------------------------------------
2934 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2935 Loc : constant Source_Ptr := Sloc (N);
2936 Scop : constant Entity_Id := Current_Scope;
2937 Designator : Entity_Id;
2939 Null_Body : Node_Id := Empty;
2941 -- Start of processing for Analyze_Subprogram_Declaration
2944 -- Null procedures are not allowed in SPARK
2946 if Nkind (Specification (N)) = N_Procedure_Specification
2947 and then Null_Present (Specification (N))
2949 Check_SPARK_Restriction ("null procedure is not allowed", N);
2952 -- For a null procedure, capture the profile before analysis, for
2953 -- expansion at the freeze point and at each point of call. The body
2954 -- will only be used if the procedure has preconditions. In that case
2955 -- the body is analyzed at the freeze point.
2957 if Nkind (Specification (N)) = N_Procedure_Specification
2958 and then Null_Present (Specification (N))
2959 and then Expander_Active
2962 Make_Subprogram_Body (Loc,
2964 New_Copy_Tree (Specification (N)),
2967 Handled_Statement_Sequence =>
2968 Make_Handled_Sequence_Of_Statements (Loc,
2969 Statements => New_List (Make_Null_Statement (Loc))));
2971 -- Create new entities for body and formals
2973 Set_Defining_Unit_Name (Specification (Null_Body),
2974 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))));
2975 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
2977 Form := First (Parameter_Specifications (Specification (Null_Body)));
2978 while Present (Form) loop
2979 Set_Defining_Identifier (Form,
2980 Make_Defining_Identifier (Loc,
2981 Chars (Defining_Identifier (Form))));
2983 -- Resolve the types of the formals now, because the freeze point
2984 -- may appear in a different context, e.g. an instantiation.
2986 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
2987 Find_Type (Parameter_Type (Form));
2990 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
2992 Find_Type (Subtype_Mark (Parameter_Type (Form)));
2996 -- the case of a null procedure with a formal that is an
2997 -- access_to_subprogram type, and that is used as an actual
2998 -- in an instantiation is left to the enthusiastic reader.
3006 if Is_Protected_Type (Current_Scope) then
3007 Error_Msg_N ("protected operation cannot be a null procedure", N);
3011 Designator := Analyze_Subprogram_Specification (Specification (N));
3012 Generate_Definition (Designator);
3013 -- ??? why this call, already in Analyze_Subprogram_Specification
3015 if Debug_Flag_C then
3016 Write_Str ("==> subprogram spec ");
3017 Write_Name (Chars (Designator));
3018 Write_Str (" from ");
3019 Write_Location (Sloc (N));
3024 if Nkind (Specification (N)) = N_Procedure_Specification
3025 and then Null_Present (Specification (N))
3027 Set_Has_Completion (Designator);
3029 if Present (Null_Body) then
3030 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
3031 Set_Body_To_Inline (N, Null_Body);
3032 Set_Is_Inlined (Designator);
3036 Validate_RCI_Subprogram_Declaration (N);
3037 New_Overloaded_Entity (Designator);
3038 Check_Delayed_Subprogram (Designator);
3040 -- If the type of the first formal of the current subprogram is a
3041 -- nongeneric tagged private type, mark the subprogram as being a
3042 -- private primitive. Ditto if this is a function with controlling
3043 -- result, and the return type is currently private. In both cases,
3044 -- the type of the controlling argument or result must be in the
3045 -- current scope for the operation to be primitive.
3047 if Has_Controlling_Result (Designator)
3048 and then Is_Private_Type (Etype (Designator))
3049 and then Scope (Etype (Designator)) = Current_Scope
3050 and then not Is_Generic_Actual_Type (Etype (Designator))
3052 Set_Is_Private_Primitive (Designator);
3054 elsif Present (First_Formal (Designator)) then
3056 Formal_Typ : constant Entity_Id :=
3057 Etype (First_Formal (Designator));
3059 Set_Is_Private_Primitive (Designator,
3060 Is_Tagged_Type (Formal_Typ)
3061 and then Scope (Formal_Typ) = Current_Scope
3062 and then Is_Private_Type (Formal_Typ)
3063 and then not Is_Generic_Actual_Type (Formal_Typ));
3067 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
3070 if Ada_Version >= Ada_2005
3071 and then Comes_From_Source (N)
3072 and then Is_Dispatching_Operation (Designator)
3079 if Has_Controlling_Result (Designator) then
3080 Etyp := Etype (Designator);
3083 E := First_Entity (Designator);
3085 and then Is_Formal (E)
3086 and then not Is_Controlling_Formal (E)
3094 if Is_Access_Type (Etyp) then
3095 Etyp := Directly_Designated_Type (Etyp);
3098 if Is_Interface (Etyp)
3099 and then not Is_Abstract_Subprogram (Designator)
3100 and then not (Ekind (Designator) = E_Procedure
3101 and then Null_Present (Specification (N)))
3103 Error_Msg_Name_1 := Chars (Defining_Entity (N));
3105 ("(Ada 2005) interface subprogram % must be abstract or null",
3111 -- What is the following code for, it used to be
3113 -- ??? Set_Suppress_Elaboration_Checks
3114 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
3116 -- The following seems equivalent, but a bit dubious
3118 if Elaboration_Checks_Suppressed (Designator) then
3119 Set_Kill_Elaboration_Checks (Designator);
3122 if Scop /= Standard_Standard
3123 and then not Is_Child_Unit (Designator)
3125 Set_Categorization_From_Scope (Designator, Scop);
3127 -- For a compilation unit, check for library-unit pragmas
3129 Push_Scope (Designator);
3130 Set_Categorization_From_Pragmas (N);
3131 Validate_Categorization_Dependency (N, Designator);
3135 -- For a compilation unit, set body required. This flag will only be
3136 -- reset if a valid Import or Interface pragma is processed later on.
3138 if Nkind (Parent (N)) = N_Compilation_Unit then
3139 Set_Body_Required (Parent (N), True);
3141 if Ada_Version >= Ada_2005
3142 and then Nkind (Specification (N)) = N_Procedure_Specification
3143 and then Null_Present (Specification (N))
3146 ("null procedure cannot be declared at library level", N);
3150 Generate_Reference_To_Formals (Designator);
3151 Check_Eliminated (Designator);
3153 if Debug_Flag_C then
3155 Write_Str ("<== subprogram spec ");
3156 Write_Name (Chars (Designator));
3157 Write_Str (" from ");
3158 Write_Location (Sloc (N));
3162 if Is_Protected_Type (Current_Scope) then
3164 -- Indicate that this is a protected operation, because it may be
3165 -- used in subsequent declarations within the protected type.
3167 Set_Convention (Designator, Convention_Protected);
3170 List_Inherited_Pre_Post_Aspects (Designator);
3172 if Has_Aspects (N) then
3173 Analyze_Aspect_Specifications (N, Designator);
3175 end Analyze_Subprogram_Declaration;
3177 --------------------------------------
3178 -- Analyze_Subprogram_Specification --
3179 --------------------------------------
3181 -- Reminder: N here really is a subprogram specification (not a subprogram
3182 -- declaration). This procedure is called to analyze the specification in
3183 -- both subprogram bodies and subprogram declarations (specs).
3185 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
3186 Designator : constant Entity_Id := Defining_Entity (N);
3187 Formals : constant List_Id := Parameter_Specifications (N);
3189 -- Start of processing for Analyze_Subprogram_Specification
3192 -- User-defined operator is not allowed in SPARK, except as a renaming
3194 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
3195 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
3197 Check_SPARK_Restriction ("user-defined operator is not allowed", N);
3200 -- Proceed with analysis
3202 Generate_Definition (Designator);
3203 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
3205 if Nkind (N) = N_Function_Specification then
3206 Set_Ekind (Designator, E_Function);
3207 Set_Mechanism (Designator, Default_Mechanism);
3209 Set_Ekind (Designator, E_Procedure);
3210 Set_Etype (Designator, Standard_Void_Type);
3213 -- Introduce new scope for analysis of the formals and the return type
3215 Set_Scope (Designator, Current_Scope);
3217 if Present (Formals) then
3218 Push_Scope (Designator);
3219 Process_Formals (Formals, N);
3221 -- Ada 2005 (AI-345): If this is an overriding operation of an
3222 -- inherited interface operation, and the controlling type is
3223 -- a synchronized type, replace the type with its corresponding
3224 -- record, to match the proper signature of an overriding operation.
3225 -- Same processing for an access parameter whose designated type is
3226 -- derived from a synchronized interface.
3228 if Ada_Version >= Ada_2005 then
3231 Formal_Typ : Entity_Id;
3232 Rec_Typ : Entity_Id;
3233 Desig_Typ : Entity_Id;
3236 Formal := First_Formal (Designator);
3237 while Present (Formal) loop
3238 Formal_Typ := Etype (Formal);
3240 if Is_Concurrent_Type (Formal_Typ)
3241 and then Present (Corresponding_Record_Type (Formal_Typ))
3243 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
3245 if Present (Interfaces (Rec_Typ)) then
3246 Set_Etype (Formal, Rec_Typ);
3249 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
3250 Desig_Typ := Designated_Type (Formal_Typ);
3252 if Is_Concurrent_Type (Desig_Typ)
3253 and then Present (Corresponding_Record_Type (Desig_Typ))
3255 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
3257 if Present (Interfaces (Rec_Typ)) then
3258 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
3263 Next_Formal (Formal);
3270 -- The subprogram scope is pushed and popped around the processing of
3271 -- the return type for consistency with call above to Process_Formals
3272 -- (which itself can call Analyze_Return_Type), and to ensure that any
3273 -- itype created for the return type will be associated with the proper
3276 elsif Nkind (N) = N_Function_Specification then
3277 Push_Scope (Designator);
3278 Analyze_Return_Type (N);
3284 if Nkind (N) = N_Function_Specification then
3286 -- Deal with operator symbol case
3288 if Nkind (Designator) = N_Defining_Operator_Symbol then
3289 Valid_Operator_Definition (Designator);
3292 May_Need_Actuals (Designator);
3294 -- Ada 2005 (AI-251): If the return type is abstract, verify that
3295 -- the subprogram is abstract also. This does not apply to renaming
3296 -- declarations, where abstractness is inherited.
3298 -- In case of primitives associated with abstract interface types
3299 -- the check is applied later (see Analyze_Subprogram_Declaration).
3301 if not Nkind_In (Parent (N), N_Subprogram_Renaming_Declaration,
3302 N_Abstract_Subprogram_Declaration,
3303 N_Formal_Abstract_Subprogram_Declaration)
3305 if Is_Abstract_Type (Etype (Designator))
3306 and then not Is_Interface (Etype (Designator))
3309 ("function that returns abstract type must be abstract", N);
3311 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
3312 -- access result whose designated type is abstract.
3314 elsif Nkind (Result_Definition (N)) = N_Access_Definition
3316 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
3317 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
3318 and then Ada_Version >= Ada_2012
3320 Error_Msg_N ("function whose access result designates "
3321 & "abstract type must be abstract", N);
3327 end Analyze_Subprogram_Specification;
3329 --------------------------
3330 -- Build_Body_To_Inline --
3331 --------------------------
3333 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
3334 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
3335 Original_Body : Node_Id;
3336 Body_To_Analyze : Node_Id;
3337 Max_Size : constant := 10;
3338 Stat_Count : Integer := 0;
3340 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
3341 -- Check for declarations that make inlining not worthwhile
3343 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
3344 -- Check for statements that make inlining not worthwhile: any tasking
3345 -- statement, nested at any level. Keep track of total number of
3346 -- elementary statements, as a measure of acceptable size.
3348 function Has_Pending_Instantiation return Boolean;
3349 -- If some enclosing body contains instantiations that appear before the
3350 -- corresponding generic body, the enclosing body has a freeze node so
3351 -- that it can be elaborated after the generic itself. This might
3352 -- conflict with subsequent inlinings, so that it is unsafe to try to
3353 -- inline in such a case.
3355 function Has_Single_Return return Boolean;
3356 -- In general we cannot inline functions that return unconstrained type.
3357 -- However, we can handle such functions if all return statements return
3358 -- a local variable that is the only declaration in the body of the
3359 -- function. In that case the call can be replaced by that local
3360 -- variable as is done for other inlined calls.
3362 procedure Remove_Pragmas;
3363 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
3364 -- parameter has no meaning when the body is inlined and the formals
3365 -- are rewritten. Remove it from body to inline. The analysis of the
3366 -- non-inlined body will handle the pragma properly.
3368 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
3369 -- If the body of the subprogram includes a call that returns an
3370 -- unconstrained type, the secondary stack is involved, and it
3371 -- is not worth inlining.
3373 ------------------------------
3374 -- Has_Excluded_Declaration --
3375 ------------------------------
3377 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
3380 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
3381 -- Nested subprograms make a given body ineligible for inlining, but
3382 -- we make an exception for instantiations of unchecked conversion.
3383 -- The body has not been analyzed yet, so check the name, and verify
3384 -- that the visible entity with that name is the predefined unit.
3386 -----------------------------
3387 -- Is_Unchecked_Conversion --
3388 -----------------------------
3390 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
3391 Id : constant Node_Id := Name (D);
3395 if Nkind (Id) = N_Identifier
3396 and then Chars (Id) = Name_Unchecked_Conversion
3398 Conv := Current_Entity (Id);
3400 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
3401 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
3403 Conv := Current_Entity (Selector_Name (Id));
3408 return Present (Conv)
3409 and then Is_Predefined_File_Name
3410 (Unit_File_Name (Get_Source_Unit (Conv)))
3411 and then Is_Intrinsic_Subprogram (Conv);
3412 end Is_Unchecked_Conversion;
3414 -- Start of processing for Has_Excluded_Declaration
3418 while Present (D) loop
3419 if (Nkind (D) = N_Function_Instantiation
3420 and then not Is_Unchecked_Conversion (D))
3421 or else Nkind_In (D, N_Protected_Type_Declaration,
3422 N_Package_Declaration,
3423 N_Package_Instantiation,
3425 N_Procedure_Instantiation,
3426 N_Task_Type_Declaration)
3429 ("cannot inline & (non-allowed declaration)?", D, Subp);
3437 end Has_Excluded_Declaration;
3439 ----------------------------
3440 -- Has_Excluded_Statement --
3441 ----------------------------
3443 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
3449 while Present (S) loop
3450 Stat_Count := Stat_Count + 1;
3452 if Nkind_In (S, N_Abort_Statement,
3453 N_Asynchronous_Select,
3454 N_Conditional_Entry_Call,
3455 N_Delay_Relative_Statement,
3456 N_Delay_Until_Statement,
3461 ("cannot inline & (non-allowed statement)?", S, Subp);
3464 elsif Nkind (S) = N_Block_Statement then
3465 if Present (Declarations (S))
3466 and then Has_Excluded_Declaration (Declarations (S))
3470 elsif Present (Handled_Statement_Sequence (S))
3473 (Exception_Handlers (Handled_Statement_Sequence (S)))
3475 Has_Excluded_Statement
3476 (Statements (Handled_Statement_Sequence (S))))
3481 elsif Nkind (S) = N_Case_Statement then
3482 E := First (Alternatives (S));
3483 while Present (E) loop
3484 if Has_Excluded_Statement (Statements (E)) then
3491 elsif Nkind (S) = N_If_Statement then
3492 if Has_Excluded_Statement (Then_Statements (S)) then
3496 if Present (Elsif_Parts (S)) then
3497 E := First (Elsif_Parts (S));
3498 while Present (E) loop
3499 if Has_Excluded_Statement (Then_Statements (E)) then
3506 if Present (Else_Statements (S))
3507 and then Has_Excluded_Statement (Else_Statements (S))
3512 elsif Nkind (S) = N_Loop_Statement
3513 and then Has_Excluded_Statement (Statements (S))
3517 elsif Nkind (S) = N_Extended_Return_Statement then
3518 if Has_Excluded_Statement
3519 (Statements (Handled_Statement_Sequence (S)))
3521 (Exception_Handlers (Handled_Statement_Sequence (S)))
3531 end Has_Excluded_Statement;
3533 -------------------------------
3534 -- Has_Pending_Instantiation --
3535 -------------------------------
3537 function Has_Pending_Instantiation return Boolean is
3542 while Present (S) loop
3543 if Is_Compilation_Unit (S)
3544 or else Is_Child_Unit (S)
3548 elsif Ekind (S) = E_Package
3549 and then Has_Forward_Instantiation (S)
3558 end Has_Pending_Instantiation;
3560 ------------------------
3561 -- Has_Single_Return --
3562 ------------------------
3564 function Has_Single_Return return Boolean is
3565 Return_Statement : Node_Id := Empty;
3567 function Check_Return (N : Node_Id) return Traverse_Result;
3573 function Check_Return (N : Node_Id) return Traverse_Result is
3575 if Nkind (N) = N_Simple_Return_Statement then
3576 if Present (Expression (N))
3577 and then Is_Entity_Name (Expression (N))
3579 if No (Return_Statement) then
3580 Return_Statement := N;
3583 elsif Chars (Expression (N)) =
3584 Chars (Expression (Return_Statement))
3592 -- A return statement within an extended return is a noop
3595 elsif No (Expression (N))
3596 and then Nkind (Parent (Parent (N))) =
3597 N_Extended_Return_Statement
3602 -- Expression has wrong form
3607 -- We can only inline a build-in-place function if
3608 -- it has a single extended return.
3610 elsif Nkind (N) = N_Extended_Return_Statement then
3611 if No (Return_Statement) then
3612 Return_Statement := N;
3624 function Check_All_Returns is new Traverse_Func (Check_Return);
3626 -- Start of processing for Has_Single_Return
3629 if Check_All_Returns (N) /= OK then
3632 elsif Nkind (Return_Statement) = N_Extended_Return_Statement then
3636 return Present (Declarations (N))
3637 and then Present (First (Declarations (N)))
3638 and then Chars (Expression (Return_Statement)) =
3639 Chars (Defining_Identifier (First (Declarations (N))));
3641 end Has_Single_Return;
3643 --------------------
3644 -- Remove_Pragmas --
3645 --------------------
3647 procedure Remove_Pragmas is
3652 Decl := First (Declarations (Body_To_Analyze));
3653 while Present (Decl) loop
3656 if Nkind (Decl) = N_Pragma
3657 and then (Pragma_Name (Decl) = Name_Unreferenced
3659 Pragma_Name (Decl) = Name_Unmodified)
3668 --------------------------
3669 -- Uses_Secondary_Stack --
3670 --------------------------
3672 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3673 function Check_Call (N : Node_Id) return Traverse_Result;
3674 -- Look for function calls that return an unconstrained type
3680 function Check_Call (N : Node_Id) return Traverse_Result is
3682 if Nkind (N) = N_Function_Call
3683 and then Is_Entity_Name (Name (N))
3684 and then Is_Composite_Type (Etype (Entity (Name (N))))
3685 and then not Is_Constrained (Etype (Entity (Name (N))))
3688 ("cannot inline & (call returns unconstrained type)?",
3696 function Check_Calls is new Traverse_Func (Check_Call);
3699 return Check_Calls (Bod) = Abandon;
3700 end Uses_Secondary_Stack;
3702 -- Start of processing for Build_Body_To_Inline
3705 -- Return immediately if done already
3707 if Nkind (Decl) = N_Subprogram_Declaration
3708 and then Present (Body_To_Inline (Decl))
3712 -- Functions that return unconstrained composite types require
3713 -- secondary stack handling, and cannot currently be inlined, unless
3714 -- all return statements return a local variable that is the first
3715 -- local declaration in the body.
3717 elsif Ekind (Subp) = E_Function
3718 and then not Is_Scalar_Type (Etype (Subp))
3719 and then not Is_Access_Type (Etype (Subp))
3720 and then not Is_Constrained (Etype (Subp))
3722 if not Has_Single_Return then
3724 ("cannot inline & (unconstrained return type)?", N, Subp);
3728 -- Ditto for functions that return controlled types, where controlled
3729 -- actions interfere in complex ways with inlining.
3731 elsif Ekind (Subp) = E_Function
3732 and then Needs_Finalization (Etype (Subp))
3735 ("cannot inline & (controlled return type)?", N, Subp);
3739 if Present (Declarations (N))
3740 and then Has_Excluded_Declaration (Declarations (N))
3745 if Present (Handled_Statement_Sequence (N)) then
3746 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3748 ("cannot inline& (exception handler)?",
3749 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3753 Has_Excluded_Statement
3754 (Statements (Handled_Statement_Sequence (N)))
3760 -- We do not inline a subprogram that is too large, unless it is
3761 -- marked Inline_Always. This pragma does not suppress the other
3762 -- checks on inlining (forbidden declarations, handlers, etc).
3764 if Stat_Count > Max_Size
3765 and then not Has_Pragma_Inline_Always (Subp)
3767 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3771 if Has_Pending_Instantiation then
3773 ("cannot inline& (forward instance within enclosing body)?",
3778 -- Within an instance, the body to inline must be treated as a nested
3779 -- generic, so that the proper global references are preserved.
3781 -- Note that we do not do this at the library level, because it is not
3782 -- needed, and furthermore this causes trouble if front end inlining
3783 -- is activated (-gnatN).
3785 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3786 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3787 Original_Body := Copy_Generic_Node (N, Empty, True);
3789 Original_Body := Copy_Separate_Tree (N);
3792 -- We need to capture references to the formals in order to substitute
3793 -- the actuals at the point of inlining, i.e. instantiation. To treat
3794 -- the formals as globals to the body to inline, we nest it within
3795 -- a dummy parameterless subprogram, declared within the real one.
3796 -- To avoid generating an internal name (which is never public, and
3797 -- which affects serial numbers of other generated names), we use
3798 -- an internal symbol that cannot conflict with user declarations.
3800 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3801 Set_Defining_Unit_Name
3802 (Specification (Original_Body),
3803 Make_Defining_Identifier (Sloc (N), Name_uParent));
3804 Set_Corresponding_Spec (Original_Body, Empty);
3806 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3808 -- Set return type of function, which is also global and does not need
3811 if Ekind (Subp) = E_Function then
3812 Set_Result_Definition (Specification (Body_To_Analyze),
3813 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3816 if No (Declarations (N)) then
3817 Set_Declarations (N, New_List (Body_To_Analyze));
3819 Append (Body_To_Analyze, Declarations (N));
3822 Expander_Mode_Save_And_Set (False);
3825 Analyze (Body_To_Analyze);
3826 Push_Scope (Defining_Entity (Body_To_Analyze));
3827 Save_Global_References (Original_Body);
3829 Remove (Body_To_Analyze);
3831 Expander_Mode_Restore;
3833 -- Restore environment if previously saved
3835 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3839 -- If secondary stk used there is no point in inlining. We have
3840 -- already issued the warning in this case, so nothing to do.
3842 if Uses_Secondary_Stack (Body_To_Analyze) then
3846 Set_Body_To_Inline (Decl, Original_Body);
3847 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3848 Set_Is_Inlined (Subp);
3849 end Build_Body_To_Inline;
3855 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3857 -- Do not emit warning if this is a predefined unit which is not the
3858 -- main unit. With validity checks enabled, some predefined subprograms
3859 -- may contain nested subprograms and become ineligible for inlining.
3861 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3862 and then not In_Extended_Main_Source_Unit (Subp)
3866 elsif Has_Pragma_Inline_Always (Subp) then
3868 -- Remove last character (question mark) to make this into an error,
3869 -- because the Inline_Always pragma cannot be obeyed.
3871 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3873 elsif Ineffective_Inline_Warnings then
3874 Error_Msg_NE (Msg, N, Subp);
3878 -----------------------
3879 -- Check_Conformance --
3880 -----------------------
3882 procedure Check_Conformance
3883 (New_Id : Entity_Id;
3885 Ctype : Conformance_Type;
3887 Conforms : out Boolean;
3888 Err_Loc : Node_Id := Empty;
3889 Get_Inst : Boolean := False;
3890 Skip_Controlling_Formals : Boolean := False)
3892 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3893 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
3894 -- If Errmsg is True, then processing continues to post an error message
3895 -- for conformance error on given node. Two messages are output. The
3896 -- first message points to the previous declaration with a general "no
3897 -- conformance" message. The second is the detailed reason, supplied as
3898 -- Msg. The parameter N provide information for a possible & insertion
3899 -- in the message, and also provides the location for posting the
3900 -- message in the absence of a specified Err_Loc location.
3902 -----------------------
3903 -- Conformance_Error --
3904 -----------------------
3906 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3913 if No (Err_Loc) then
3919 Error_Msg_Sloc := Sloc (Old_Id);
3922 when Type_Conformant =>
3923 Error_Msg_N -- CODEFIX
3924 ("not type conformant with declaration#!", Enode);
3926 when Mode_Conformant =>
3927 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3929 ("not mode conformant with operation inherited#!",
3933 ("not mode conformant with declaration#!", Enode);
3936 when Subtype_Conformant =>
3937 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3939 ("not subtype conformant with operation inherited#!",
3943 ("not subtype conformant with declaration#!", Enode);
3946 when Fully_Conformant =>
3947 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3948 Error_Msg_N -- CODEFIX
3949 ("not fully conformant with operation inherited#!",
3952 Error_Msg_N -- CODEFIX
3953 ("not fully conformant with declaration#!", Enode);
3957 Error_Msg_NE (Msg, Enode, N);
3959 end Conformance_Error;
3963 Old_Type : constant Entity_Id := Etype (Old_Id);
3964 New_Type : constant Entity_Id := Etype (New_Id);
3965 Old_Formal : Entity_Id;
3966 New_Formal : Entity_Id;
3967 Access_Types_Match : Boolean;
3968 Old_Formal_Base : Entity_Id;
3969 New_Formal_Base : Entity_Id;
3971 -- Start of processing for Check_Conformance
3976 -- We need a special case for operators, since they don't appear
3979 if Ctype = Type_Conformant then
3980 if Ekind (New_Id) = E_Operator
3981 and then Operator_Matches_Spec (New_Id, Old_Id)
3987 -- If both are functions/operators, check return types conform
3989 if Old_Type /= Standard_Void_Type
3990 and then New_Type /= Standard_Void_Type
3993 -- If we are checking interface conformance we omit controlling
3994 -- arguments and result, because we are only checking the conformance
3995 -- of the remaining parameters.
3997 if Has_Controlling_Result (Old_Id)
3998 and then Has_Controlling_Result (New_Id)
3999 and then Skip_Controlling_Formals
4003 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
4004 Conformance_Error ("\return type does not match!", New_Id);
4008 -- Ada 2005 (AI-231): In case of anonymous access types check the
4009 -- null-exclusion and access-to-constant attributes match.
4011 if Ada_Version >= Ada_2005
4012 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
4014 (Can_Never_Be_Null (Old_Type)
4015 /= Can_Never_Be_Null (New_Type)
4016 or else Is_Access_Constant (Etype (Old_Type))
4017 /= Is_Access_Constant (Etype (New_Type)))
4019 Conformance_Error ("\return type does not match!", New_Id);
4023 -- If either is a function/operator and the other isn't, error
4025 elsif Old_Type /= Standard_Void_Type
4026 or else New_Type /= Standard_Void_Type
4028 Conformance_Error ("\functions can only match functions!", New_Id);
4032 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
4033 -- If this is a renaming as body, refine error message to indicate that
4034 -- the conflict is with the original declaration. If the entity is not
4035 -- frozen, the conventions don't have to match, the one of the renamed
4036 -- entity is inherited.
4038 if Ctype >= Subtype_Conformant then
4039 if Convention (Old_Id) /= Convention (New_Id) then
4041 if not Is_Frozen (New_Id) then
4044 elsif Present (Err_Loc)
4045 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
4046 and then Present (Corresponding_Spec (Err_Loc))
4048 Error_Msg_Name_1 := Chars (New_Id);
4050 Name_Ada + Convention_Id'Pos (Convention (New_Id));
4051 Conformance_Error ("\prior declaration for% has convention %!");
4054 Conformance_Error ("\calling conventions do not match!");
4059 elsif Is_Formal_Subprogram (Old_Id)
4060 or else Is_Formal_Subprogram (New_Id)
4062 Conformance_Error ("\formal subprograms not allowed!");
4067 -- Deal with parameters
4069 -- Note: we use the entity information, rather than going directly
4070 -- to the specification in the tree. This is not only simpler, but
4071 -- absolutely necessary for some cases of conformance tests between
4072 -- operators, where the declaration tree simply does not exist!
4074 Old_Formal := First_Formal (Old_Id);
4075 New_Formal := First_Formal (New_Id);
4076 while Present (Old_Formal) and then Present (New_Formal) loop
4077 if Is_Controlling_Formal (Old_Formal)
4078 and then Is_Controlling_Formal (New_Formal)
4079 and then Skip_Controlling_Formals
4081 -- The controlling formals will have different types when
4082 -- comparing an interface operation with its match, but both
4083 -- or neither must be access parameters.
4085 if Is_Access_Type (Etype (Old_Formal))
4087 Is_Access_Type (Etype (New_Formal))
4089 goto Skip_Controlling_Formal;
4092 ("\access parameter does not match!", New_Formal);
4096 if Ctype = Fully_Conformant then
4098 -- Names must match. Error message is more accurate if we do
4099 -- this before checking that the types of the formals match.
4101 if Chars (Old_Formal) /= Chars (New_Formal) then
4102 Conformance_Error ("\name & does not match!", New_Formal);
4104 -- Set error posted flag on new formal as well to stop
4105 -- junk cascaded messages in some cases.
4107 Set_Error_Posted (New_Formal);
4111 -- Null exclusion must match
4113 if Null_Exclusion_Present (Parent (Old_Formal))
4115 Null_Exclusion_Present (Parent (New_Formal))
4117 -- Only give error if both come from source. This should be
4118 -- investigated some time, since it should not be needed ???
4120 if Comes_From_Source (Old_Formal)
4122 Comes_From_Source (New_Formal)
4125 ("\null exclusion for & does not match", New_Formal);
4127 -- Mark error posted on the new formal to avoid duplicated
4128 -- complaint about types not matching.
4130 Set_Error_Posted (New_Formal);
4135 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
4136 -- case occurs whenever a subprogram is being renamed and one of its
4137 -- parameters imposes a null exclusion. For example:
4139 -- type T is null record;
4140 -- type Acc_T is access T;
4141 -- subtype Acc_T_Sub is Acc_T;
4143 -- procedure P (Obj : not null Acc_T_Sub); -- itype
4144 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
4147 Old_Formal_Base := Etype (Old_Formal);
4148 New_Formal_Base := Etype (New_Formal);
4151 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
4152 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
4155 Access_Types_Match := Ada_Version >= Ada_2005
4157 -- Ensure that this rule is only applied when New_Id is a
4158 -- renaming of Old_Id.
4160 and then Nkind (Parent (Parent (New_Id))) =
4161 N_Subprogram_Renaming_Declaration
4162 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
4163 and then Present (Entity (Name (Parent (Parent (New_Id)))))
4164 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
4166 -- Now handle the allowed access-type case
4168 and then Is_Access_Type (Old_Formal_Base)
4169 and then Is_Access_Type (New_Formal_Base)
4171 -- The type kinds must match. The only exception occurs with
4172 -- multiple generics of the form:
4175 -- type F is private; type A is private;
4176 -- type F_Ptr is access F; type A_Ptr is access A;
4177 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
4178 -- package F_Pack is ... package A_Pack is
4179 -- package F_Inst is
4180 -- new F_Pack (A, A_Ptr, A_P);
4182 -- When checking for conformance between the parameters of A_P
4183 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
4184 -- because the compiler has transformed A_Ptr into a subtype of
4185 -- F_Ptr. We catch this case in the code below.
4187 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
4189 (Is_Generic_Type (Old_Formal_Base)
4190 and then Is_Generic_Type (New_Formal_Base)
4191 and then Is_Internal (New_Formal_Base)
4192 and then Etype (Etype (New_Formal_Base)) =
4194 and then Directly_Designated_Type (Old_Formal_Base) =
4195 Directly_Designated_Type (New_Formal_Base)
4196 and then ((Is_Itype (Old_Formal_Base)
4197 and then Can_Never_Be_Null (Old_Formal_Base))
4199 (Is_Itype (New_Formal_Base)
4200 and then Can_Never_Be_Null (New_Formal_Base)));
4202 -- Types must always match. In the visible part of an instance,
4203 -- usual overloading rules for dispatching operations apply, and
4204 -- we check base types (not the actual subtypes).
4206 if In_Instance_Visible_Part
4207 and then Is_Dispatching_Operation (New_Id)
4209 if not Conforming_Types
4210 (T1 => Base_Type (Etype (Old_Formal)),
4211 T2 => Base_Type (Etype (New_Formal)),
4213 Get_Inst => Get_Inst)
4214 and then not Access_Types_Match
4216 Conformance_Error ("\type of & does not match!", New_Formal);
4220 elsif not Conforming_Types
4221 (T1 => Old_Formal_Base,
4222 T2 => New_Formal_Base,
4224 Get_Inst => Get_Inst)
4225 and then not Access_Types_Match
4227 -- Don't give error message if old type is Any_Type. This test
4228 -- avoids some cascaded errors, e.g. in case of a bad spec.
4230 if Errmsg and then Old_Formal_Base = Any_Type then
4233 Conformance_Error ("\type of & does not match!", New_Formal);
4239 -- For mode conformance, mode must match
4241 if Ctype >= Mode_Conformant then
4242 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
4243 if not Ekind_In (New_Id, E_Function, E_Procedure)
4244 or else not Is_Primitive_Wrapper (New_Id)
4246 Conformance_Error ("\mode of & does not match!", New_Formal);
4250 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
4252 if Is_Protected_Type
4253 (Corresponding_Concurrent_Type (T))
4255 Error_Msg_PT (T, New_Id);
4258 ("\mode of & does not match!", New_Formal);
4265 -- Part of mode conformance for access types is having the same
4266 -- constant modifier.
4268 elsif Access_Types_Match
4269 and then Is_Access_Constant (Old_Formal_Base) /=
4270 Is_Access_Constant (New_Formal_Base)
4273 ("\constant modifier does not match!", New_Formal);
4278 if Ctype >= Subtype_Conformant then
4280 -- Ada 2005 (AI-231): In case of anonymous access types check
4281 -- the null-exclusion and access-to-constant attributes must
4282 -- match. For null exclusion, we test the types rather than the
4283 -- formals themselves, since the attribute is only set reliably
4284 -- on the formals in the Ada 95 case, and we exclude the case
4285 -- where Old_Formal is marked as controlling, to avoid errors
4286 -- when matching completing bodies with dispatching declarations
4287 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
4289 if Ada_Version >= Ada_2005
4290 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
4291 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
4293 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
4294 Can_Never_Be_Null (Etype (New_Formal))
4296 not Is_Controlling_Formal (Old_Formal))
4298 Is_Access_Constant (Etype (Old_Formal)) /=
4299 Is_Access_Constant (Etype (New_Formal)))
4301 -- Do not complain if error already posted on New_Formal. This
4302 -- avoids some redundant error messages.
4304 and then not Error_Posted (New_Formal)
4306 -- It is allowed to omit the null-exclusion in case of stream
4307 -- attribute subprograms. We recognize stream subprograms
4308 -- through their TSS-generated suffix.
4311 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
4313 if TSS_Name /= TSS_Stream_Read
4314 and then TSS_Name /= TSS_Stream_Write
4315 and then TSS_Name /= TSS_Stream_Input
4316 and then TSS_Name /= TSS_Stream_Output
4319 ("\type of & does not match!", New_Formal);
4326 -- Full conformance checks
4328 if Ctype = Fully_Conformant then
4330 -- We have checked already that names match
4332 if Parameter_Mode (Old_Formal) = E_In_Parameter then
4334 -- Check default expressions for in parameters
4337 NewD : constant Boolean :=
4338 Present (Default_Value (New_Formal));
4339 OldD : constant Boolean :=
4340 Present (Default_Value (Old_Formal));
4342 if NewD or OldD then
4344 -- The old default value has been analyzed because the
4345 -- current full declaration will have frozen everything
4346 -- before. The new default value has not been analyzed,
4347 -- so analyze it now before we check for conformance.
4350 Push_Scope (New_Id);
4351 Preanalyze_Spec_Expression
4352 (Default_Value (New_Formal), Etype (New_Formal));
4356 if not (NewD and OldD)
4357 or else not Fully_Conformant_Expressions
4358 (Default_Value (Old_Formal),
4359 Default_Value (New_Formal))
4362 ("\default expression for & does not match!",
4371 -- A couple of special checks for Ada 83 mode. These checks are
4372 -- skipped if either entity is an operator in package Standard,
4373 -- or if either old or new instance is not from the source program.
4375 if Ada_Version = Ada_83
4376 and then Sloc (Old_Id) > Standard_Location
4377 and then Sloc (New_Id) > Standard_Location
4378 and then Comes_From_Source (Old_Id)
4379 and then Comes_From_Source (New_Id)
4382 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
4383 New_Param : constant Node_Id := Declaration_Node (New_Formal);
4386 -- Explicit IN must be present or absent in both cases. This
4387 -- test is required only in the full conformance case.
4389 if In_Present (Old_Param) /= In_Present (New_Param)
4390 and then Ctype = Fully_Conformant
4393 ("\(Ada 83) IN must appear in both declarations",
4398 -- Grouping (use of comma in param lists) must be the same
4399 -- This is where we catch a misconformance like:
4402 -- A : Integer; B : Integer
4404 -- which are represented identically in the tree except
4405 -- for the setting of the flags More_Ids and Prev_Ids.
4407 if More_Ids (Old_Param) /= More_Ids (New_Param)
4408 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
4411 ("\grouping of & does not match!", New_Formal);
4417 -- This label is required when skipping controlling formals
4419 <<Skip_Controlling_Formal>>
4421 Next_Formal (Old_Formal);
4422 Next_Formal (New_Formal);
4425 if Present (Old_Formal) then
4426 Conformance_Error ("\too few parameters!");
4429 elsif Present (New_Formal) then
4430 Conformance_Error ("\too many parameters!", New_Formal);
4433 end Check_Conformance;
4435 -----------------------
4436 -- Check_Conventions --
4437 -----------------------
4439 procedure Check_Conventions (Typ : Entity_Id) is
4440 Ifaces_List : Elist_Id;
4442 procedure Check_Convention (Op : Entity_Id);
4443 -- Verify that the convention of inherited dispatching operation Op is
4444 -- consistent among all subprograms it overrides. In order to minimize
4445 -- the search, Search_From is utilized to designate a specific point in
4446 -- the list rather than iterating over the whole list once more.
4448 ----------------------
4449 -- Check_Convention --
4450 ----------------------
4452 procedure Check_Convention (Op : Entity_Id) is
4453 Iface_Elmt : Elmt_Id;
4454 Iface_Prim_Elmt : Elmt_Id;
4455 Iface_Prim : Entity_Id;
4458 Iface_Elmt := First_Elmt (Ifaces_List);
4459 while Present (Iface_Elmt) loop
4461 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
4462 while Present (Iface_Prim_Elmt) loop
4463 Iface_Prim := Node (Iface_Prim_Elmt);
4465 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
4466 and then Convention (Iface_Prim) /= Convention (Op)
4469 ("inconsistent conventions in primitive operations", Typ);
4471 Error_Msg_Name_1 := Chars (Op);
4472 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
4473 Error_Msg_Sloc := Sloc (Op);
4475 if Comes_From_Source (Op) or else No (Alias (Op)) then
4476 if not Present (Overridden_Operation (Op)) then
4477 Error_Msg_N ("\\primitive % defined #", Typ);
4480 ("\\overriding operation % with " &
4481 "convention % defined #", Typ);
4484 else pragma Assert (Present (Alias (Op)));
4485 Error_Msg_Sloc := Sloc (Alias (Op));
4487 ("\\inherited operation % with " &
4488 "convention % defined #", Typ);
4491 Error_Msg_Name_1 := Chars (Op);
4493 Get_Convention_Name (Convention (Iface_Prim));
4494 Error_Msg_Sloc := Sloc (Iface_Prim);
4496 ("\\overridden operation % with " &
4497 "convention % defined #", Typ);
4499 -- Avoid cascading errors
4504 Next_Elmt (Iface_Prim_Elmt);
4507 Next_Elmt (Iface_Elmt);
4509 end Check_Convention;
4513 Prim_Op : Entity_Id;
4514 Prim_Op_Elmt : Elmt_Id;
4516 -- Start of processing for Check_Conventions
4519 if not Has_Interfaces (Typ) then
4523 Collect_Interfaces (Typ, Ifaces_List);
4525 -- The algorithm checks every overriding dispatching operation against
4526 -- all the corresponding overridden dispatching operations, detecting
4527 -- differences in conventions.
4529 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
4530 while Present (Prim_Op_Elmt) loop
4531 Prim_Op := Node (Prim_Op_Elmt);
4533 -- A small optimization: skip the predefined dispatching operations
4534 -- since they always have the same convention.
4536 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
4537 Check_Convention (Prim_Op);
4540 Next_Elmt (Prim_Op_Elmt);
4542 end Check_Conventions;
4544 ------------------------------
4545 -- Check_Delayed_Subprogram --
4546 ------------------------------
4548 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
4551 procedure Possible_Freeze (T : Entity_Id);
4552 -- T is the type of either a formal parameter or of the return type.
4553 -- If T is not yet frozen and needs a delayed freeze, then the
4554 -- subprogram itself must be delayed. If T is the limited view of an
4555 -- incomplete type the subprogram must be frozen as well, because
4556 -- T may depend on local types that have not been frozen yet.
4558 ---------------------
4559 -- Possible_Freeze --
4560 ---------------------
4562 procedure Possible_Freeze (T : Entity_Id) is
4564 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
4565 Set_Has_Delayed_Freeze (Designator);
4567 elsif Is_Access_Type (T)
4568 and then Has_Delayed_Freeze (Designated_Type (T))
4569 and then not Is_Frozen (Designated_Type (T))
4571 Set_Has_Delayed_Freeze (Designator);
4573 elsif Ekind (T) = E_Incomplete_Type and then From_With_Type (T) then
4574 Set_Has_Delayed_Freeze (Designator);
4576 -- AI05-0151: In Ada 2012, Incomplete types can appear in the profile
4577 -- of a subprogram or entry declaration.
4579 elsif Ekind (T) = E_Incomplete_Type
4580 and then Ada_Version >= Ada_2012
4582 Set_Has_Delayed_Freeze (Designator);
4585 end Possible_Freeze;
4587 -- Start of processing for Check_Delayed_Subprogram
4590 -- All subprograms, including abstract subprograms, may need a freeze
4591 -- node if some formal type or the return type needs one.
4593 Possible_Freeze (Etype (Designator));
4594 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
4596 -- Need delayed freeze if any of the formal types themselves need
4597 -- a delayed freeze and are not yet frozen.
4599 F := First_Formal (Designator);
4600 while Present (F) loop
4601 Possible_Freeze (Etype (F));
4602 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
4606 -- Mark functions that return by reference. Note that it cannot be
4607 -- done for delayed_freeze subprograms because the underlying
4608 -- returned type may not be known yet (for private types)
4610 if not Has_Delayed_Freeze (Designator)
4611 and then Expander_Active
4614 Typ : constant Entity_Id := Etype (Designator);
4615 Utyp : constant Entity_Id := Underlying_Type (Typ);
4618 if Is_Immutably_Limited_Type (Typ) then
4619 Set_Returns_By_Ref (Designator);
4621 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
4622 Set_Returns_By_Ref (Designator);
4626 end Check_Delayed_Subprogram;
4628 ------------------------------------
4629 -- Check_Discriminant_Conformance --
4630 ------------------------------------
4632 procedure Check_Discriminant_Conformance
4637 Old_Discr : Entity_Id := First_Discriminant (Prev);
4638 New_Discr : Node_Id := First (Discriminant_Specifications (N));
4639 New_Discr_Id : Entity_Id;
4640 New_Discr_Type : Entity_Id;
4642 procedure Conformance_Error (Msg : String; N : Node_Id);
4643 -- Post error message for conformance error on given node. Two messages
4644 -- are output. The first points to the previous declaration with a
4645 -- general "no conformance" message. The second is the detailed reason,
4646 -- supplied as Msg. The parameter N provide information for a possible
4647 -- & insertion in the message.
4649 -----------------------
4650 -- Conformance_Error --
4651 -----------------------
4653 procedure Conformance_Error (Msg : String; N : Node_Id) is
4655 Error_Msg_Sloc := Sloc (Prev_Loc);
4656 Error_Msg_N -- CODEFIX
4657 ("not fully conformant with declaration#!", N);
4658 Error_Msg_NE (Msg, N, N);
4659 end Conformance_Error;
4661 -- Start of processing for Check_Discriminant_Conformance
4664 while Present (Old_Discr) and then Present (New_Discr) loop
4666 New_Discr_Id := Defining_Identifier (New_Discr);
4668 -- The subtype mark of the discriminant on the full type has not
4669 -- been analyzed so we do it here. For an access discriminant a new
4672 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
4674 Access_Definition (N, Discriminant_Type (New_Discr));
4677 Analyze (Discriminant_Type (New_Discr));
4678 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
4680 -- Ada 2005: if the discriminant definition carries a null
4681 -- exclusion, create an itype to check properly for consistency
4682 -- with partial declaration.
4684 if Is_Access_Type (New_Discr_Type)
4685 and then Null_Exclusion_Present (New_Discr)
4688 Create_Null_Excluding_Itype
4689 (T => New_Discr_Type,
4690 Related_Nod => New_Discr,
4691 Scope_Id => Current_Scope);
4695 if not Conforming_Types
4696 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
4698 Conformance_Error ("type of & does not match!", New_Discr_Id);
4701 -- Treat the new discriminant as an occurrence of the old one,
4702 -- for navigation purposes, and fill in some semantic
4703 -- information, for completeness.
4705 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
4706 Set_Etype (New_Discr_Id, Etype (Old_Discr));
4707 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4712 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4713 Conformance_Error ("name & does not match!", New_Discr_Id);
4717 -- Default expressions must match
4720 NewD : constant Boolean :=
4721 Present (Expression (New_Discr));
4722 OldD : constant Boolean :=
4723 Present (Expression (Parent (Old_Discr)));
4726 if NewD or OldD then
4728 -- The old default value has been analyzed and expanded,
4729 -- because the current full declaration will have frozen
4730 -- everything before. The new default values have not been
4731 -- expanded, so expand now to check conformance.
4734 Preanalyze_Spec_Expression
4735 (Expression (New_Discr), New_Discr_Type);
4738 if not (NewD and OldD)
4739 or else not Fully_Conformant_Expressions
4740 (Expression (Parent (Old_Discr)),
4741 Expression (New_Discr))
4745 ("default expression for & does not match!",
4752 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4754 if Ada_Version = Ada_83 then
4756 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4759 -- Grouping (use of comma in param lists) must be the same
4760 -- This is where we catch a misconformance like:
4763 -- A : Integer; B : Integer
4765 -- which are represented identically in the tree except
4766 -- for the setting of the flags More_Ids and Prev_Ids.
4768 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4769 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4772 ("grouping of & does not match!", New_Discr_Id);
4778 Next_Discriminant (Old_Discr);
4782 if Present (Old_Discr) then
4783 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4786 elsif Present (New_Discr) then
4788 ("too many discriminants!", Defining_Identifier (New_Discr));
4791 end Check_Discriminant_Conformance;
4793 ----------------------------
4794 -- Check_Fully_Conformant --
4795 ----------------------------
4797 procedure Check_Fully_Conformant
4798 (New_Id : Entity_Id;
4800 Err_Loc : Node_Id := Empty)
4803 pragma Warnings (Off, Result);
4806 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4807 end Check_Fully_Conformant;
4809 ---------------------------
4810 -- Check_Mode_Conformant --
4811 ---------------------------
4813 procedure Check_Mode_Conformant
4814 (New_Id : Entity_Id;
4816 Err_Loc : Node_Id := Empty;
4817 Get_Inst : Boolean := False)
4820 pragma Warnings (Off, Result);
4823 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4824 end Check_Mode_Conformant;
4826 --------------------------------
4827 -- Check_Overriding_Indicator --
4828 --------------------------------
4830 procedure Check_Overriding_Indicator
4832 Overridden_Subp : Entity_Id;
4833 Is_Primitive : Boolean)
4839 -- No overriding indicator for literals
4841 if Ekind (Subp) = E_Enumeration_Literal then
4844 elsif Ekind (Subp) = E_Entry then
4845 Decl := Parent (Subp);
4847 -- No point in analyzing a malformed operator
4849 elsif Nkind (Subp) = N_Defining_Operator_Symbol
4850 and then Error_Posted (Subp)
4855 Decl := Unit_Declaration_Node (Subp);
4858 if Nkind_In (Decl, N_Subprogram_Body,
4859 N_Subprogram_Body_Stub,
4860 N_Subprogram_Declaration,
4861 N_Abstract_Subprogram_Declaration,
4862 N_Subprogram_Renaming_Declaration)
4864 Spec := Specification (Decl);
4866 elsif Nkind (Decl) = N_Entry_Declaration then
4873 -- The overriding operation is type conformant with the overridden one,
4874 -- but the names of the formals are not required to match. If the names
4875 -- appear permuted in the overriding operation, this is a possible
4876 -- source of confusion that is worth diagnosing. Controlling formals
4877 -- often carry names that reflect the type, and it is not worthwhile
4878 -- requiring that their names match.
4880 if Present (Overridden_Subp)
4881 and then Nkind (Subp) /= N_Defining_Operator_Symbol
4888 Form1 := First_Formal (Subp);
4889 Form2 := First_Formal (Overridden_Subp);
4891 -- If the overriding operation is a synchronized operation, skip
4892 -- the first parameter of the overridden operation, which is
4893 -- implicit in the new one. If the operation is declared in the
4894 -- body it is not primitive and all formals must match.
4896 if Is_Concurrent_Type (Scope (Subp))
4897 and then Is_Tagged_Type (Scope (Subp))
4898 and then not Has_Completion (Scope (Subp))
4900 Form2 := Next_Formal (Form2);
4903 if Present (Form1) then
4904 Form1 := Next_Formal (Form1);
4905 Form2 := Next_Formal (Form2);
4908 while Present (Form1) loop
4909 if not Is_Controlling_Formal (Form1)
4910 and then Present (Next_Formal (Form2))
4911 and then Chars (Form1) = Chars (Next_Formal (Form2))
4913 Error_Msg_Node_2 := Alias (Overridden_Subp);
4914 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
4916 ("& does not match corresponding formal of&#",
4921 Next_Formal (Form1);
4922 Next_Formal (Form2);
4927 -- If there is an overridden subprogram, then check that there is no
4928 -- "not overriding" indicator, and mark the subprogram as overriding.
4929 -- This is not done if the overridden subprogram is marked as hidden,
4930 -- which can occur for the case of inherited controlled operations
4931 -- (see Derive_Subprogram), unless the inherited subprogram's parent
4932 -- subprogram is not itself hidden. (Note: This condition could probably
4933 -- be simplified, leaving out the testing for the specific controlled
4934 -- cases, but it seems safer and clearer this way, and echoes similar
4935 -- special-case tests of this kind in other places.)
4937 if Present (Overridden_Subp)
4938 and then (not Is_Hidden (Overridden_Subp)
4940 ((Chars (Overridden_Subp) = Name_Initialize
4942 Chars (Overridden_Subp) = Name_Adjust
4944 Chars (Overridden_Subp) = Name_Finalize)
4945 and then Present (Alias (Overridden_Subp))
4946 and then not Is_Hidden (Alias (Overridden_Subp))))
4948 if Must_Not_Override (Spec) then
4949 Error_Msg_Sloc := Sloc (Overridden_Subp);
4951 if Ekind (Subp) = E_Entry then
4953 ("entry & overrides inherited operation #", Spec, Subp);
4956 ("subprogram & overrides inherited operation #", Spec, Subp);
4959 elsif Is_Subprogram (Subp) then
4960 if Is_Init_Proc (Subp) then
4963 elsif No (Overridden_Operation (Subp)) then
4965 -- For entities generated by Derive_Subprograms the overridden
4966 -- operation is the inherited primitive (which is available
4967 -- through the attribute alias)
4969 if (Is_Dispatching_Operation (Subp)
4970 or else Is_Dispatching_Operation (Overridden_Subp))
4971 and then not Comes_From_Source (Overridden_Subp)
4972 and then Find_Dispatching_Type (Overridden_Subp) =
4973 Find_Dispatching_Type (Subp)
4974 and then Present (Alias (Overridden_Subp))
4975 and then Comes_From_Source (Alias (Overridden_Subp))
4977 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
4980 Set_Overridden_Operation (Subp, Overridden_Subp);
4985 -- If primitive flag is set or this is a protected operation, then
4986 -- the operation is overriding at the point of its declaration, so
4987 -- warn if necessary. Otherwise it may have been declared before the
4988 -- operation it overrides and no check is required.
4991 and then not Must_Override (Spec)
4992 and then (Is_Primitive
4993 or else Ekind (Scope (Subp)) = E_Protected_Type)
4995 Style.Missing_Overriding (Decl, Subp);
4998 -- If Subp is an operator, it may override a predefined operation, if
4999 -- it is defined in the same scope as the type to which it applies.
5000 -- In that case Overridden_Subp is empty because of our implicit
5001 -- representation for predefined operators. We have to check whether the
5002 -- signature of Subp matches that of a predefined operator. Note that
5003 -- first argument provides the name of the operator, and the second
5004 -- argument the signature that may match that of a standard operation.
5005 -- If the indicator is overriding, then the operator must match a
5006 -- predefined signature, because we know already that there is no
5007 -- explicit overridden operation.
5009 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
5010 if Must_Not_Override (Spec) then
5012 -- If this is not a primitive or a protected subprogram, then
5013 -- "not overriding" is illegal.
5016 and then Ekind (Scope (Subp)) /= E_Protected_Type
5019 ("overriding indicator only allowed "
5020 & "if subprogram is primitive", Subp);
5022 elsif Can_Override_Operator (Subp) then
5024 ("subprogram& overrides predefined operator ", Spec, Subp);
5027 elsif Must_Override (Spec) then
5028 if No (Overridden_Operation (Subp))
5029 and then not Can_Override_Operator (Subp)
5031 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5034 elsif not Error_Posted (Subp)
5035 and then Style_Check
5036 and then Can_Override_Operator (Subp)
5038 not Is_Predefined_File_Name
5039 (Unit_File_Name (Get_Source_Unit (Subp)))
5041 -- If style checks are enabled, indicate that the indicator is
5042 -- missing. However, at the point of declaration, the type of
5043 -- which this is a primitive operation may be private, in which
5044 -- case the indicator would be premature.
5046 if Has_Private_Declaration (Etype (Subp))
5047 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
5051 Style.Missing_Overriding (Decl, Subp);
5055 elsif Must_Override (Spec) then
5056 if Ekind (Subp) = E_Entry then
5057 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
5059 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5062 -- If the operation is marked "not overriding" and it's not primitive
5063 -- then an error is issued, unless this is an operation of a task or
5064 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
5065 -- has been specified have already been checked above.
5067 elsif Must_Not_Override (Spec)
5068 and then not Is_Primitive
5069 and then Ekind (Subp) /= E_Entry
5070 and then Ekind (Scope (Subp)) /= E_Protected_Type
5073 ("overriding indicator only allowed if subprogram is primitive",
5077 end Check_Overriding_Indicator;
5083 -- Note: this procedure needs to know far too much about how the expander
5084 -- messes with exceptions. The use of the flag Exception_Junk and the
5085 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
5086 -- works, but is not very clean. It would be better if the expansion
5087 -- routines would leave Original_Node working nicely, and we could use
5088 -- Original_Node here to ignore all the peculiar expander messing ???
5090 procedure Check_Returns
5094 Proc : Entity_Id := Empty)
5098 procedure Check_Statement_Sequence (L : List_Id);
5099 -- Internal recursive procedure to check a list of statements for proper
5100 -- termination by a return statement (or a transfer of control or a
5101 -- compound statement that is itself internally properly terminated).
5103 ------------------------------
5104 -- Check_Statement_Sequence --
5105 ------------------------------
5107 procedure Check_Statement_Sequence (L : List_Id) is
5112 Raise_Exception_Call : Boolean;
5113 -- Set True if statement sequence terminated by Raise_Exception call
5114 -- or a Reraise_Occurrence call.
5117 Raise_Exception_Call := False;
5119 -- Get last real statement
5121 Last_Stm := Last (L);
5123 -- Deal with digging out exception handler statement sequences that
5124 -- have been transformed by the local raise to goto optimization.
5125 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
5126 -- optimization has occurred, we are looking at something like:
5129 -- original stmts in block
5133 -- goto L1; | omitted if No_Exception_Propagation
5138 -- goto L3; -- skip handler when exception not raised
5140 -- <<L1>> -- target label for local exception
5154 -- and what we have to do is to dig out the estmts1 and estmts2
5155 -- sequences (which were the original sequences of statements in
5156 -- the exception handlers) and check them.
5158 if Nkind (Last_Stm) = N_Label
5159 and then Exception_Junk (Last_Stm)
5165 exit when Nkind (Stm) /= N_Block_Statement;
5166 exit when not Exception_Junk (Stm);
5169 exit when Nkind (Stm) /= N_Label;
5170 exit when not Exception_Junk (Stm);
5171 Check_Statement_Sequence
5172 (Statements (Handled_Statement_Sequence (Next (Stm))));
5177 exit when Nkind (Stm) /= N_Goto_Statement;
5178 exit when not Exception_Junk (Stm);
5182 -- Don't count pragmas
5184 while Nkind (Last_Stm) = N_Pragma
5186 -- Don't count call to SS_Release (can happen after Raise_Exception)
5189 (Nkind (Last_Stm) = N_Procedure_Call_Statement
5191 Nkind (Name (Last_Stm)) = N_Identifier
5193 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
5195 -- Don't count exception junk
5198 (Nkind_In (Last_Stm, N_Goto_Statement,
5200 N_Object_Declaration)
5201 and then Exception_Junk (Last_Stm))
5202 or else Nkind (Last_Stm) in N_Push_xxx_Label
5203 or else Nkind (Last_Stm) in N_Pop_xxx_Label
5208 -- Here we have the "real" last statement
5210 Kind := Nkind (Last_Stm);
5212 -- Transfer of control, OK. Note that in the No_Return procedure
5213 -- case, we already diagnosed any explicit return statements, so
5214 -- we can treat them as OK in this context.
5216 if Is_Transfer (Last_Stm) then
5219 -- Check cases of explicit non-indirect procedure calls
5221 elsif Kind = N_Procedure_Call_Statement
5222 and then Is_Entity_Name (Name (Last_Stm))
5224 -- Check call to Raise_Exception procedure which is treated
5225 -- specially, as is a call to Reraise_Occurrence.
5227 -- We suppress the warning in these cases since it is likely that
5228 -- the programmer really does not expect to deal with the case
5229 -- of Null_Occurrence, and thus would find a warning about a
5230 -- missing return curious, and raising Program_Error does not
5231 -- seem such a bad behavior if this does occur.
5233 -- Note that in the Ada 2005 case for Raise_Exception, the actual
5234 -- behavior will be to raise Constraint_Error (see AI-329).
5236 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
5238 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
5240 Raise_Exception_Call := True;
5242 -- For Raise_Exception call, test first argument, if it is
5243 -- an attribute reference for a 'Identity call, then we know
5244 -- that the call cannot possibly return.
5247 Arg : constant Node_Id :=
5248 Original_Node (First_Actual (Last_Stm));
5250 if Nkind (Arg) = N_Attribute_Reference
5251 and then Attribute_Name (Arg) = Name_Identity
5258 -- If statement, need to look inside if there is an else and check
5259 -- each constituent statement sequence for proper termination.
5261 elsif Kind = N_If_Statement
5262 and then Present (Else_Statements (Last_Stm))
5264 Check_Statement_Sequence (Then_Statements (Last_Stm));
5265 Check_Statement_Sequence (Else_Statements (Last_Stm));
5267 if Present (Elsif_Parts (Last_Stm)) then
5269 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
5272 while Present (Elsif_Part) loop
5273 Check_Statement_Sequence (Then_Statements (Elsif_Part));
5281 -- Case statement, check each case for proper termination
5283 elsif Kind = N_Case_Statement then
5287 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
5288 while Present (Case_Alt) loop
5289 Check_Statement_Sequence (Statements (Case_Alt));
5290 Next_Non_Pragma (Case_Alt);
5296 -- Block statement, check its handled sequence of statements
5298 elsif Kind = N_Block_Statement then
5304 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
5313 -- Loop statement. If there is an iteration scheme, we can definitely
5314 -- fall out of the loop. Similarly if there is an exit statement, we
5315 -- can fall out. In either case we need a following return.
5317 elsif Kind = N_Loop_Statement then
5318 if Present (Iteration_Scheme (Last_Stm))
5319 or else Has_Exit (Entity (Identifier (Last_Stm)))
5323 -- A loop with no exit statement or iteration scheme is either
5324 -- an infinite loop, or it has some other exit (raise/return).
5325 -- In either case, no warning is required.
5331 -- Timed entry call, check entry call and delay alternatives
5333 -- Note: in expanded code, the timed entry call has been converted
5334 -- to a set of expanded statements on which the check will work
5335 -- correctly in any case.
5337 elsif Kind = N_Timed_Entry_Call then
5339 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5340 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
5343 -- If statement sequence of entry call alternative is missing,
5344 -- then we can definitely fall through, and we post the error
5345 -- message on the entry call alternative itself.
5347 if No (Statements (ECA)) then
5350 -- If statement sequence of delay alternative is missing, then
5351 -- we can definitely fall through, and we post the error
5352 -- message on the delay alternative itself.
5354 -- Note: if both ECA and DCA are missing the return, then we
5355 -- post only one message, should be enough to fix the bugs.
5356 -- If not we will get a message next time on the DCA when the
5359 elsif No (Statements (DCA)) then
5362 -- Else check both statement sequences
5365 Check_Statement_Sequence (Statements (ECA));
5366 Check_Statement_Sequence (Statements (DCA));
5371 -- Conditional entry call, check entry call and else part
5373 -- Note: in expanded code, the conditional entry call has been
5374 -- converted to a set of expanded statements on which the check
5375 -- will work correctly in any case.
5377 elsif Kind = N_Conditional_Entry_Call then
5379 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5382 -- If statement sequence of entry call alternative is missing,
5383 -- then we can definitely fall through, and we post the error
5384 -- message on the entry call alternative itself.
5386 if No (Statements (ECA)) then
5389 -- Else check statement sequence and else part
5392 Check_Statement_Sequence (Statements (ECA));
5393 Check_Statement_Sequence (Else_Statements (Last_Stm));
5399 -- If we fall through, issue appropriate message
5402 if not Raise_Exception_Call then
5404 ("?RETURN statement missing following this statement!",
5407 ("\?Program_Error may be raised at run time!",
5411 -- Note: we set Err even though we have not issued a warning
5412 -- because we still have a case of a missing return. This is
5413 -- an extremely marginal case, probably will never be noticed
5414 -- but we might as well get it right.
5418 -- Otherwise we have the case of a procedure marked No_Return
5421 if not Raise_Exception_Call then
5423 ("?implied return after this statement " &
5424 "will raise Program_Error",
5427 ("\?procedure & is marked as No_Return!",
5432 RE : constant Node_Id :=
5433 Make_Raise_Program_Error (Sloc (Last_Stm),
5434 Reason => PE_Implicit_Return);
5436 Insert_After (Last_Stm, RE);
5440 end Check_Statement_Sequence;
5442 -- Start of processing for Check_Returns
5446 Check_Statement_Sequence (Statements (HSS));
5448 if Present (Exception_Handlers (HSS)) then
5449 Handler := First_Non_Pragma (Exception_Handlers (HSS));
5450 while Present (Handler) loop
5451 Check_Statement_Sequence (Statements (Handler));
5452 Next_Non_Pragma (Handler);
5457 -------------------------------
5458 -- Check_Subprogram_Contract --
5459 -------------------------------
5461 procedure Check_Subprogram_Contract (Spec_Id : Entity_Id) is
5463 -- Inherited : constant Subprogram_List :=
5464 -- Inherited_Subprograms (Spec_Id);
5465 -- List of subprograms inherited by this subprogram
5467 Last_Postcondition : Node_Id := Empty;
5468 -- Last postcondition on the subprogram, or else Empty if either no
5469 -- postcondition or only inherited postconditions.
5471 Attribute_Result_Mentioned : Boolean := False;
5472 -- Whether attribute 'Result is mentioned in a postcondition
5474 Post_State_Mentioned : Boolean := False;
5475 -- Whether some expression mentioned in a postcondition can have a
5476 -- different value in the post-state than in the pre-state.
5478 function Check_Attr_Result (N : Node_Id) return Traverse_Result;
5479 -- Check whether N is a reference to the attribute 'Result, and if so
5480 -- set Attribute_Result_Mentioned and return Abandon. Otherwise return
5483 function Check_Post_State (N : Node_Id) return Traverse_Result;
5484 -- Check whether the value of evaluating N can be different in the
5485 -- post-state, compared to the same evaluation in the pre-state, and
5486 -- if so set Post_State_Mentioned and return Abandon. Return Skip on
5487 -- reference to attribute 'Old, in order to ignore its prefix, which
5488 -- is precisely evaluated in the pre-state. Otherwise return OK.
5490 procedure Process_Post_Conditions
5493 -- This processes the Spec_PPC_List from Spec, processing any
5494 -- postconditions from the list. If Class is True, then only
5495 -- postconditions marked with Class_Present are considered. The
5496 -- caller has checked that Spec_PPC_List is non-Empty.
5498 function Find_Attribute_Result is new Traverse_Func (Check_Attr_Result);
5500 function Find_Post_State is new Traverse_Func (Check_Post_State);
5502 -----------------------
5503 -- Check_Attr_Result --
5504 -----------------------
5506 function Check_Attr_Result (N : Node_Id) return Traverse_Result is
5508 if Nkind (N) = N_Attribute_Reference
5510 Get_Attribute_Id (Attribute_Name (N)) = Attribute_Result
5512 Attribute_Result_Mentioned := True;
5517 end Check_Attr_Result;
5519 ----------------------
5520 -- Check_Post_State --
5521 ----------------------
5523 function Check_Post_State (N : Node_Id) return Traverse_Result is
5524 Found : Boolean := False;
5528 when N_Function_Call |
5529 N_Explicit_Dereference =>
5535 E : constant Entity_Id := Entity (N);
5537 if Is_Entity_Name (N)
5538 and then Present (E)
5539 and then Ekind (E) in Assignable_Kind
5545 when N_Attribute_Reference =>
5546 case Get_Attribute_Id (Attribute_Name (N)) is
5547 when Attribute_Old =>
5549 when Attribute_Result =>
5560 Post_State_Mentioned := True;
5565 end Check_Post_State;
5567 -----------------------------
5568 -- Process_Post_Conditions --
5569 -----------------------------
5571 procedure Process_Post_Conditions
5577 Ignored : Traverse_Final_Result;
5578 pragma Unreferenced (Ignored);
5581 Prag := Spec_PPC_List (Contract (Spec));
5584 Arg := First (Pragma_Argument_Associations (Prag));
5586 -- Since pre- and postconditions are listed in reverse order, the
5587 -- first postcondition in the list is the last in the source.
5589 if Pragma_Name (Prag) = Name_Postcondition
5591 and then No (Last_Postcondition)
5593 Last_Postcondition := Prag;
5596 -- For functions, look for presence of 'Result in postcondition
5598 if Ekind_In (Spec_Id, E_Function, E_Generic_Function) then
5599 Ignored := Find_Attribute_Result (Arg);
5602 -- For each individual non-inherited postcondition, look for
5603 -- presence of an expression that could be evaluated differently
5606 if Pragma_Name (Prag) = Name_Postcondition
5609 Post_State_Mentioned := False;
5610 Ignored := Find_Post_State (Arg);
5612 if not Post_State_Mentioned then
5613 Error_Msg_N ("?postcondition only refers to pre-state",
5618 Prag := Next_Pragma (Prag);
5619 exit when No (Prag);
5621 end Process_Post_Conditions;
5623 -- Start of processing for Check_Subprogram_Contract
5626 if not Warn_On_Suspicious_Contract then
5630 if Present (Spec_PPC_List (Contract (Spec_Id))) then
5631 Process_Post_Conditions (Spec_Id, Class => False);
5634 -- Process inherited postconditions
5636 -- Code is currently commented out as, in some cases, it causes crashes
5637 -- because Direct_Primitive_Operations is not available for a private
5638 -- type. This may cause more warnings to be issued than necessary.
5640 -- for J in Inherited'Range loop
5641 -- if Present (Spec_PPC_List (Contract (Inherited (J)))) then
5642 -- Process_Post_Conditions (Inherited (J), Class => True);
5646 -- Issue warning for functions whose postcondition does not mention
5647 -- 'Result after all postconditions have been processed.
5649 if Ekind_In (Spec_Id, E_Function, E_Generic_Function)
5650 and then Present (Last_Postcondition)
5651 and then not Attribute_Result_Mentioned
5653 Error_Msg_N ("?function postcondition does not mention result",
5654 Last_Postcondition);
5656 end Check_Subprogram_Contract;
5658 ----------------------------
5659 -- Check_Subprogram_Order --
5660 ----------------------------
5662 procedure Check_Subprogram_Order (N : Node_Id) is
5664 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
5665 -- This is used to check if S1 > S2 in the sense required by this
5666 -- test, for example nameab < namec, but name2 < name10.
5668 -----------------------------
5669 -- Subprogram_Name_Greater --
5670 -----------------------------
5672 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
5677 -- Remove trailing numeric parts
5680 while S1 (L1) in '0' .. '9' loop
5685 while S2 (L2) in '0' .. '9' loop
5689 -- If non-numeric parts non-equal, that's decisive
5691 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
5694 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
5697 -- If non-numeric parts equal, compare suffixed numeric parts. Note
5698 -- that a missing suffix is treated as numeric zero in this test.
5702 while L1 < S1'Last loop
5704 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
5708 while L2 < S2'Last loop
5710 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
5715 end Subprogram_Name_Greater;
5717 -- Start of processing for Check_Subprogram_Order
5720 -- Check body in alpha order if this is option
5723 and then Style_Check_Order_Subprograms
5724 and then Nkind (N) = N_Subprogram_Body
5725 and then Comes_From_Source (N)
5726 and then In_Extended_Main_Source_Unit (N)
5730 renames Scope_Stack.Table
5731 (Scope_Stack.Last).Last_Subprogram_Name;
5733 Body_Id : constant Entity_Id :=
5734 Defining_Entity (Specification (N));
5737 Get_Decoded_Name_String (Chars (Body_Id));
5740 if Subprogram_Name_Greater
5741 (LSN.all, Name_Buffer (1 .. Name_Len))
5743 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
5749 LSN := new String'(Name_Buffer (1 .. Name_Len));
5752 end Check_Subprogram_Order;
5754 ------------------------------
5755 -- Check_Subtype_Conformant --
5756 ------------------------------
5758 procedure Check_Subtype_Conformant
5759 (New_Id : Entity_Id;
5761 Err_Loc : Node_Id := Empty;
5762 Skip_Controlling_Formals : Boolean := False)
5765 pragma Warnings (Off, Result);
5768 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
5769 Skip_Controlling_Formals => Skip_Controlling_Formals);
5770 end Check_Subtype_Conformant;
5772 ---------------------------
5773 -- Check_Type_Conformant --
5774 ---------------------------
5776 procedure Check_Type_Conformant
5777 (New_Id : Entity_Id;
5779 Err_Loc : Node_Id := Empty)
5782 pragma Warnings (Off, Result);
5785 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
5786 end Check_Type_Conformant;
5788 ---------------------------
5789 -- Can_Override_Operator --
5790 ---------------------------
5792 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
5795 if Nkind (Subp) /= N_Defining_Operator_Symbol then
5799 Typ := Base_Type (Etype (First_Formal (Subp)));
5801 return Operator_Matches_Spec (Subp, Subp)
5802 and then Scope (Subp) = Scope (Typ)
5803 and then not Is_Class_Wide_Type (Typ);
5805 end Can_Override_Operator;
5807 ----------------------
5808 -- Conforming_Types --
5809 ----------------------
5811 function Conforming_Types
5814 Ctype : Conformance_Type;
5815 Get_Inst : Boolean := False) return Boolean
5817 Type_1 : Entity_Id := T1;
5818 Type_2 : Entity_Id := T2;
5819 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
5821 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
5822 -- If neither T1 nor T2 are generic actual types, or if they are in
5823 -- different scopes (e.g. parent and child instances), then verify that
5824 -- the base types are equal. Otherwise T1 and T2 must be on the same
5825 -- subtype chain. The whole purpose of this procedure is to prevent
5826 -- spurious ambiguities in an instantiation that may arise if two
5827 -- distinct generic types are instantiated with the same actual.
5829 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
5830 -- An access parameter can designate an incomplete type. If the
5831 -- incomplete type is the limited view of a type from a limited_
5832 -- with_clause, check whether the non-limited view is available. If
5833 -- it is a (non-limited) incomplete type, get the full view.
5835 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
5836 -- Returns True if and only if either T1 denotes a limited view of T2
5837 -- or T2 denotes a limited view of T1. This can arise when the limited
5838 -- with view of a type is used in a subprogram declaration and the
5839 -- subprogram body is in the scope of a regular with clause for the
5840 -- same unit. In such a case, the two type entities can be considered
5841 -- identical for purposes of conformance checking.
5843 ----------------------
5844 -- Base_Types_Match --
5845 ----------------------
5847 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
5852 elsif Base_Type (T1) = Base_Type (T2) then
5854 -- The following is too permissive. A more precise test should
5855 -- check that the generic actual is an ancestor subtype of the
5858 return not Is_Generic_Actual_Type (T1)
5859 or else not Is_Generic_Actual_Type (T2)
5860 or else Scope (T1) /= Scope (T2);
5865 end Base_Types_Match;
5867 --------------------------
5868 -- Find_Designated_Type --
5869 --------------------------
5871 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
5875 Desig := Directly_Designated_Type (T);
5877 if Ekind (Desig) = E_Incomplete_Type then
5879 -- If regular incomplete type, get full view if available
5881 if Present (Full_View (Desig)) then
5882 Desig := Full_View (Desig);
5884 -- If limited view of a type, get non-limited view if available,
5885 -- and check again for a regular incomplete type.
5887 elsif Present (Non_Limited_View (Desig)) then
5888 Desig := Get_Full_View (Non_Limited_View (Desig));
5893 end Find_Designated_Type;
5895 -------------------------------
5896 -- Matches_Limited_With_View --
5897 -------------------------------
5899 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
5901 -- In some cases a type imported through a limited_with clause, and
5902 -- its nonlimited view are both visible, for example in an anonymous
5903 -- access-to-class-wide type in a formal. Both entities designate the
5906 if From_With_Type (T1)
5907 and then T2 = Available_View (T1)
5911 elsif From_With_Type (T2)
5912 and then T1 = Available_View (T2)
5916 elsif From_With_Type (T1)
5917 and then From_With_Type (T2)
5918 and then Available_View (T1) = Available_View (T2)
5925 end Matches_Limited_With_View;
5927 -- Start of processing for Conforming_Types
5930 -- The context is an instance association for a formal
5931 -- access-to-subprogram type; the formal parameter types require
5932 -- mapping because they may denote other formal parameters of the
5936 Type_1 := Get_Instance_Of (T1);
5937 Type_2 := Get_Instance_Of (T2);
5940 -- If one of the types is a view of the other introduced by a limited
5941 -- with clause, treat these as conforming for all purposes.
5943 if Matches_Limited_With_View (T1, T2) then
5946 elsif Base_Types_Match (Type_1, Type_2) then
5947 return Ctype <= Mode_Conformant
5948 or else Subtypes_Statically_Match (Type_1, Type_2);
5950 elsif Is_Incomplete_Or_Private_Type (Type_1)
5951 and then Present (Full_View (Type_1))
5952 and then Base_Types_Match (Full_View (Type_1), Type_2)
5954 return Ctype <= Mode_Conformant
5955 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
5957 elsif Ekind (Type_2) = E_Incomplete_Type
5958 and then Present (Full_View (Type_2))
5959 and then Base_Types_Match (Type_1, Full_View (Type_2))
5961 return Ctype <= Mode_Conformant
5962 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5964 elsif Is_Private_Type (Type_2)
5965 and then In_Instance
5966 and then Present (Full_View (Type_2))
5967 and then Base_Types_Match (Type_1, Full_View (Type_2))
5969 return Ctype <= Mode_Conformant
5970 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5973 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
5974 -- treated recursively because they carry a signature.
5976 Are_Anonymous_Access_To_Subprogram_Types :=
5977 Ekind (Type_1) = Ekind (Type_2)
5979 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
5981 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
5983 -- Test anonymous access type case. For this case, static subtype
5984 -- matching is required for mode conformance (RM 6.3.1(15)). We check
5985 -- the base types because we may have built internal subtype entities
5986 -- to handle null-excluding types (see Process_Formals).
5988 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
5990 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
5991 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
5994 Desig_1 : Entity_Id;
5995 Desig_2 : Entity_Id;
5998 -- In Ada2005, access constant indicators must match for
5999 -- subtype conformance.
6001 if Ada_Version >= Ada_2005
6002 and then Ctype >= Subtype_Conformant
6004 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
6009 Desig_1 := Find_Designated_Type (Type_1);
6010 Desig_2 := Find_Designated_Type (Type_2);
6012 -- If the context is an instance association for a formal
6013 -- access-to-subprogram type; formal access parameter designated
6014 -- types require mapping because they may denote other formal
6015 -- parameters of the generic unit.
6018 Desig_1 := Get_Instance_Of (Desig_1);
6019 Desig_2 := Get_Instance_Of (Desig_2);
6022 -- It is possible for a Class_Wide_Type to be introduced for an
6023 -- incomplete type, in which case there is a separate class_ wide
6024 -- type for the full view. The types conform if their Etypes
6025 -- conform, i.e. one may be the full view of the other. This can
6026 -- only happen in the context of an access parameter, other uses
6027 -- of an incomplete Class_Wide_Type are illegal.
6029 if Is_Class_Wide_Type (Desig_1)
6031 Is_Class_Wide_Type (Desig_2)
6035 (Etype (Base_Type (Desig_1)),
6036 Etype (Base_Type (Desig_2)), Ctype);
6038 elsif Are_Anonymous_Access_To_Subprogram_Types then
6039 if Ada_Version < Ada_2005 then
6040 return Ctype = Type_Conformant
6042 Subtypes_Statically_Match (Desig_1, Desig_2);
6044 -- We must check the conformance of the signatures themselves
6048 Conformant : Boolean;
6051 (Desig_1, Desig_2, Ctype, False, Conformant);
6057 return Base_Type (Desig_1) = Base_Type (Desig_2)
6058 and then (Ctype = Type_Conformant
6060 Subtypes_Statically_Match (Desig_1, Desig_2));
6064 -- Otherwise definitely no match
6067 if ((Ekind (Type_1) = E_Anonymous_Access_Type
6068 and then Is_Access_Type (Type_2))
6069 or else (Ekind (Type_2) = E_Anonymous_Access_Type
6070 and then Is_Access_Type (Type_1)))
6073 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
6075 May_Hide_Profile := True;
6080 end Conforming_Types;
6082 --------------------------
6083 -- Create_Extra_Formals --
6084 --------------------------
6086 procedure Create_Extra_Formals (E : Entity_Id) is
6088 First_Extra : Entity_Id := Empty;
6089 Last_Extra : Entity_Id;
6090 Formal_Type : Entity_Id;
6091 P_Formal : Entity_Id := Empty;
6093 function Add_Extra_Formal
6094 (Assoc_Entity : Entity_Id;
6097 Suffix : String) return Entity_Id;
6098 -- Add an extra formal to the current list of formals and extra formals.
6099 -- The extra formal is added to the end of the list of extra formals,
6100 -- and also returned as the result. These formals are always of mode IN.
6101 -- The new formal has the type Typ, is declared in Scope, and its name
6102 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
6103 -- The following suffixes are currently used. They should not be changed
6104 -- without coordinating with CodePeer, which makes use of these to
6105 -- provide better messages.
6107 -- O denotes the Constrained bit.
6108 -- L denotes the accessibility level.
6109 -- BIP_xxx denotes an extra formal for a build-in-place function. See
6110 -- the full list in exp_ch6.BIP_Formal_Kind.
6112 ----------------------
6113 -- Add_Extra_Formal --
6114 ----------------------
6116 function Add_Extra_Formal
6117 (Assoc_Entity : Entity_Id;
6120 Suffix : String) return Entity_Id
6122 EF : constant Entity_Id :=
6123 Make_Defining_Identifier (Sloc (Assoc_Entity),
6124 Chars => New_External_Name (Chars (Assoc_Entity),
6128 -- A little optimization. Never generate an extra formal for the
6129 -- _init operand of an initialization procedure, since it could
6132 if Chars (Formal) = Name_uInit then
6136 Set_Ekind (EF, E_In_Parameter);
6137 Set_Actual_Subtype (EF, Typ);
6138 Set_Etype (EF, Typ);
6139 Set_Scope (EF, Scope);
6140 Set_Mechanism (EF, Default_Mechanism);
6141 Set_Formal_Validity (EF);
6143 if No (First_Extra) then
6145 Set_Extra_Formals (Scope, First_Extra);
6148 if Present (Last_Extra) then
6149 Set_Extra_Formal (Last_Extra, EF);
6155 end Add_Extra_Formal;
6157 -- Start of processing for Create_Extra_Formals
6160 -- We never generate extra formals if expansion is not active
6161 -- because we don't need them unless we are generating code.
6163 if not Expander_Active then
6167 -- If this is a derived subprogram then the subtypes of the parent
6168 -- subprogram's formal parameters will be used to determine the need
6169 -- for extra formals.
6171 if Is_Overloadable (E) and then Present (Alias (E)) then
6172 P_Formal := First_Formal (Alias (E));
6175 Last_Extra := Empty;
6176 Formal := First_Formal (E);
6177 while Present (Formal) loop
6178 Last_Extra := Formal;
6179 Next_Formal (Formal);
6182 -- If Extra_formals were already created, don't do it again. This
6183 -- situation may arise for subprogram types created as part of
6184 -- dispatching calls (see Expand_Dispatching_Call)
6186 if Present (Last_Extra) and then
6187 Present (Extra_Formal (Last_Extra))
6192 -- If the subprogram is a predefined dispatching subprogram then don't
6193 -- generate any extra constrained or accessibility level formals. In
6194 -- general we suppress these for internal subprograms (by not calling
6195 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
6196 -- generated stream attributes do get passed through because extra
6197 -- build-in-place formals are needed in some cases (limited 'Input).
6199 if Is_Predefined_Internal_Operation (E) then
6200 goto Test_For_BIP_Extras;
6203 Formal := First_Formal (E);
6204 while Present (Formal) loop
6206 -- Create extra formal for supporting the attribute 'Constrained.
6207 -- The case of a private type view without discriminants also
6208 -- requires the extra formal if the underlying type has defaulted
6211 if Ekind (Formal) /= E_In_Parameter then
6212 if Present (P_Formal) then
6213 Formal_Type := Etype (P_Formal);
6215 Formal_Type := Etype (Formal);
6218 -- Do not produce extra formals for Unchecked_Union parameters.
6219 -- Jump directly to the end of the loop.
6221 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
6222 goto Skip_Extra_Formal_Generation;
6225 if not Has_Discriminants (Formal_Type)
6226 and then Ekind (Formal_Type) in Private_Kind
6227 and then Present (Underlying_Type (Formal_Type))
6229 Formal_Type := Underlying_Type (Formal_Type);
6232 -- Suppress the extra formal if formal's subtype is constrained or
6233 -- indefinite, or we're compiling for Ada 2012 and the underlying
6234 -- type is tagged and limited. In Ada 2012, a limited tagged type
6235 -- can have defaulted discriminants, but 'Constrained is required
6236 -- to return True, so the formal is never needed (see AI05-0214).
6237 -- Note that this ensures consistency of calling sequences for
6238 -- dispatching operations when some types in a class have defaults
6239 -- on discriminants and others do not (and requiring the extra
6240 -- formal would introduce distributed overhead).
6242 if Has_Discriminants (Formal_Type)
6243 and then not Is_Constrained (Formal_Type)
6244 and then not Is_Indefinite_Subtype (Formal_Type)
6245 and then (Ada_Version < Ada_2012
6247 not (Is_Tagged_Type (Underlying_Type (Formal_Type))
6248 and then Is_Limited_Type (Formal_Type)))
6250 Set_Extra_Constrained
6251 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
6255 -- Create extra formal for supporting accessibility checking. This
6256 -- is done for both anonymous access formals and formals of named
6257 -- access types that are marked as controlling formals. The latter
6258 -- case can occur when Expand_Dispatching_Call creates a subprogram
6259 -- type and substitutes the types of access-to-class-wide actuals
6260 -- for the anonymous access-to-specific-type of controlling formals.
6261 -- Base_Type is applied because in cases where there is a null
6262 -- exclusion the formal may have an access subtype.
6264 -- This is suppressed if we specifically suppress accessibility
6265 -- checks at the package level for either the subprogram, or the
6266 -- package in which it resides. However, we do not suppress it
6267 -- simply if the scope has accessibility checks suppressed, since
6268 -- this could cause trouble when clients are compiled with a
6269 -- different suppression setting. The explicit checks at the
6270 -- package level are safe from this point of view.
6272 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
6273 or else (Is_Controlling_Formal (Formal)
6274 and then Is_Access_Type (Base_Type (Etype (Formal)))))
6276 (Explicit_Suppress (E, Accessibility_Check)
6278 Explicit_Suppress (Scope (E), Accessibility_Check))
6281 or else Present (Extra_Accessibility (P_Formal)))
6283 Set_Extra_Accessibility
6284 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
6287 -- This label is required when skipping extra formal generation for
6288 -- Unchecked_Union parameters.
6290 <<Skip_Extra_Formal_Generation>>
6292 if Present (P_Formal) then
6293 Next_Formal (P_Formal);
6296 Next_Formal (Formal);
6299 <<Test_For_BIP_Extras>>
6301 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
6302 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
6304 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
6306 Result_Subt : constant Entity_Id := Etype (E);
6308 Discard : Entity_Id;
6309 pragma Warnings (Off, Discard);
6312 -- In the case of functions with unconstrained result subtypes,
6313 -- add a 4-state formal indicating whether the return object is
6314 -- allocated by the caller (1), or should be allocated by the
6315 -- callee on the secondary stack (2), in the global heap (3), or
6316 -- in a user-defined storage pool (4). For the moment we just use
6317 -- Natural for the type of this formal. Note that this formal
6318 -- isn't usually needed in the case where the result subtype is
6319 -- constrained, but it is needed when the function has a tagged
6320 -- result, because generally such functions can be called in a
6321 -- dispatching context and such calls must be handled like calls
6322 -- to a class-wide function.
6324 if Needs_BIP_Alloc_Form (E) then
6327 (E, Standard_Natural,
6328 E, BIP_Formal_Suffix (BIP_Alloc_Form));
6331 -- In the case of functions whose result type needs finalization,
6332 -- add an extra formal which represents the finalization master.
6334 if Needs_BIP_Finalization_Master (E) then
6337 (E, RTE (RE_Finalization_Master_Ptr),
6338 E, BIP_Formal_Suffix (BIP_Finalization_Master));
6341 -- If the result type contains tasks, we have two extra formals:
6342 -- the master of the tasks to be created, and the caller's
6343 -- activation chain.
6345 if Has_Task (Result_Subt) then
6348 (E, RTE (RE_Master_Id),
6349 E, BIP_Formal_Suffix (BIP_Master));
6352 (E, RTE (RE_Activation_Chain_Access),
6353 E, BIP_Formal_Suffix (BIP_Activation_Chain));
6356 -- All build-in-place functions get an extra formal that will be
6357 -- passed the address of the return object within the caller.
6360 Formal_Type : constant Entity_Id :=
6362 (E_Anonymous_Access_Type, E,
6363 Scope_Id => Scope (E));
6365 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
6366 Set_Etype (Formal_Type, Formal_Type);
6367 Set_Depends_On_Private
6368 (Formal_Type, Has_Private_Component (Formal_Type));
6369 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
6370 Set_Is_Access_Constant (Formal_Type, False);
6372 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
6373 -- the designated type comes from the limited view (for
6374 -- back-end purposes).
6376 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
6378 Layout_Type (Formal_Type);
6382 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
6386 end Create_Extra_Formals;
6388 -----------------------------
6389 -- Enter_Overloaded_Entity --
6390 -----------------------------
6392 procedure Enter_Overloaded_Entity (S : Entity_Id) is
6393 E : Entity_Id := Current_Entity_In_Scope (S);
6394 C_E : Entity_Id := Current_Entity (S);
6398 Set_Has_Homonym (E);
6399 Set_Has_Homonym (S);
6402 Set_Is_Immediately_Visible (S);
6403 Set_Scope (S, Current_Scope);
6405 -- Chain new entity if front of homonym in current scope, so that
6406 -- homonyms are contiguous.
6411 while Homonym (C_E) /= E loop
6412 C_E := Homonym (C_E);
6415 Set_Homonym (C_E, S);
6419 Set_Current_Entity (S);
6424 Append_Entity (S, Current_Scope);
6425 Set_Public_Status (S);
6427 if Debug_Flag_E then
6428 Write_Str ("New overloaded entity chain: ");
6429 Write_Name (Chars (S));
6432 while Present (E) loop
6433 Write_Str (" "); Write_Int (Int (E));
6440 -- Generate warning for hiding
6443 and then Comes_From_Source (S)
6444 and then In_Extended_Main_Source_Unit (S)
6451 -- Warn unless genuine overloading. Do not emit warning on
6452 -- hiding predefined operators in Standard (these are either an
6453 -- (artifact of our implicit declarations, or simple noise) but
6454 -- keep warning on a operator defined on a local subtype, because
6455 -- of the real danger that different operators may be applied in
6456 -- various parts of the program.
6458 -- Note that if E and S have the same scope, there is never any
6459 -- hiding. Either the two conflict, and the program is illegal,
6460 -- or S is overriding an implicit inherited subprogram.
6462 if Scope (E) /= Scope (S)
6463 and then (not Is_Overloadable (E)
6464 or else Subtype_Conformant (E, S))
6465 and then (Is_Immediately_Visible (E)
6467 Is_Potentially_Use_Visible (S))
6469 if Scope (E) /= Standard_Standard then
6470 Error_Msg_Sloc := Sloc (E);
6471 Error_Msg_N ("declaration of & hides one#?", S);
6473 elsif Nkind (S) = N_Defining_Operator_Symbol
6475 Scope (Base_Type (Etype (First_Formal (S)))) /= Scope (S)
6478 ("declaration of & hides predefined operator?", S);
6483 end Enter_Overloaded_Entity;
6485 -----------------------------
6486 -- Check_Untagged_Equality --
6487 -----------------------------
6489 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
6490 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
6491 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
6495 if Nkind (Decl) = N_Subprogram_Declaration
6496 and then Is_Record_Type (Typ)
6497 and then not Is_Tagged_Type (Typ)
6499 -- If the type is not declared in a package, or if we are in the
6500 -- body of the package or in some other scope, the new operation is
6501 -- not primitive, and therefore legal, though suspicious. If the
6502 -- type is a generic actual (sub)type, the operation is not primitive
6503 -- either because the base type is declared elsewhere.
6505 if Is_Frozen (Typ) then
6506 if Ekind (Scope (Typ)) /= E_Package
6507 or else Scope (Typ) /= Current_Scope
6511 elsif Is_Generic_Actual_Type (Typ) then
6514 elsif In_Package_Body (Scope (Typ)) then
6516 ("equality operator must be declared "
6517 & "before type& is frozen", Eq_Op, Typ);
6519 ("\move declaration to package spec", Eq_Op);
6523 ("equality operator must be declared "
6524 & "before type& is frozen", Eq_Op, Typ);
6526 Obj_Decl := Next (Parent (Typ));
6527 while Present (Obj_Decl)
6528 and then Obj_Decl /= Decl
6530 if Nkind (Obj_Decl) = N_Object_Declaration
6531 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
6533 Error_Msg_NE ("type& is frozen by declaration?",
6536 ("\an equality operator cannot be declared after this "
6537 & "point (RM 4.5.2 (9.8)) (Ada 2012))?", Obj_Decl);
6545 elsif not In_Same_List (Parent (Typ), Decl)
6546 and then not Is_Limited_Type (Typ)
6549 -- This makes it illegal to have a primitive equality declared in
6550 -- the private part if the type is visible.
6552 Error_Msg_N ("equality operator appears too late", Eq_Op);
6555 end Check_Untagged_Equality;
6557 -----------------------------
6558 -- Find_Corresponding_Spec --
6559 -----------------------------
6561 function Find_Corresponding_Spec
6563 Post_Error : Boolean := True) return Entity_Id
6565 Spec : constant Node_Id := Specification (N);
6566 Designator : constant Entity_Id := Defining_Entity (Spec);
6571 E := Current_Entity (Designator);
6572 while Present (E) loop
6574 -- We are looking for a matching spec. It must have the same scope,
6575 -- and the same name, and either be type conformant, or be the case
6576 -- of a library procedure spec and its body (which belong to one
6577 -- another regardless of whether they are type conformant or not).
6579 if Scope (E) = Current_Scope then
6580 if Current_Scope = Standard_Standard
6581 or else (Ekind (E) = Ekind (Designator)
6582 and then Type_Conformant (E, Designator))
6584 -- Within an instantiation, we know that spec and body are
6585 -- subtype conformant, because they were subtype conformant
6586 -- in the generic. We choose the subtype-conformant entity
6587 -- here as well, to resolve spurious ambiguities in the
6588 -- instance that were not present in the generic (i.e. when
6589 -- two different types are given the same actual). If we are
6590 -- looking for a spec to match a body, full conformance is
6594 Set_Convention (Designator, Convention (E));
6596 -- Skip past subprogram bodies and subprogram renamings that
6597 -- may appear to have a matching spec, but that aren't fully
6598 -- conformant with it. That can occur in cases where an
6599 -- actual type causes unrelated homographs in the instance.
6601 if Nkind_In (N, N_Subprogram_Body,
6602 N_Subprogram_Renaming_Declaration)
6603 and then Present (Homonym (E))
6604 and then not Fully_Conformant (Designator, E)
6608 elsif not Subtype_Conformant (Designator, E) then
6613 -- Ada 2012 (AI05-0165): For internally generated bodies of
6614 -- null procedures locate the internally generated spec. We
6615 -- enforce mode conformance since a tagged type may inherit
6616 -- from interfaces several null primitives which differ only
6617 -- in the mode of the formals.
6619 if not (Comes_From_Source (E))
6620 and then Is_Null_Procedure (E)
6621 and then not Mode_Conformant (Designator, E)
6625 elsif not Has_Completion (E) then
6626 if Nkind (N) /= N_Subprogram_Body_Stub then
6627 Set_Corresponding_Spec (N, E);
6630 Set_Has_Completion (E);
6633 elsif Nkind (Parent (N)) = N_Subunit then
6635 -- If this is the proper body of a subunit, the completion
6636 -- flag is set when analyzing the stub.
6640 -- If E is an internal function with a controlling result
6641 -- that was created for an operation inherited by a null
6642 -- extension, it may be overridden by a body without a previous
6643 -- spec (one more reason why these should be shunned). In that
6644 -- case remove the generated body if present, because the
6645 -- current one is the explicit overriding.
6647 elsif Ekind (E) = E_Function
6648 and then Ada_Version >= Ada_2005
6649 and then not Comes_From_Source (E)
6650 and then Has_Controlling_Result (E)
6651 and then Is_Null_Extension (Etype (E))
6652 and then Comes_From_Source (Spec)
6654 Set_Has_Completion (E, False);
6657 and then Nkind (Parent (E)) = N_Function_Specification
6660 (Unit_Declaration_Node
6661 (Corresponding_Body (Unit_Declaration_Node (E))));
6665 -- If expansion is disabled, or if the wrapper function has
6666 -- not been generated yet, this a late body overriding an
6667 -- inherited operation, or it is an overriding by some other
6668 -- declaration before the controlling result is frozen. In
6669 -- either case this is a declaration of a new entity.
6675 -- If the body already exists, then this is an error unless
6676 -- the previous declaration is the implicit declaration of a
6677 -- derived subprogram. It is also legal for an instance to
6678 -- contain type conformant overloadable declarations (but the
6679 -- generic declaration may not), per 8.3(26/2).
6681 elsif No (Alias (E))
6682 and then not Is_Intrinsic_Subprogram (E)
6683 and then not In_Instance
6686 Error_Msg_Sloc := Sloc (E);
6688 if Is_Imported (E) then
6690 ("body not allowed for imported subprogram & declared#",
6693 Error_Msg_NE ("duplicate body for & declared#", N, E);
6697 -- Child units cannot be overloaded, so a conformance mismatch
6698 -- between body and a previous spec is an error.
6700 elsif Is_Child_Unit (E)
6702 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
6704 Nkind (Parent (Unit_Declaration_Node (Designator))) =
6709 ("body of child unit does not match previous declaration", N);
6717 -- On exit, we know that no previous declaration of subprogram exists
6720 end Find_Corresponding_Spec;
6722 ----------------------
6723 -- Fully_Conformant --
6724 ----------------------
6726 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6729 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
6731 end Fully_Conformant;
6733 ----------------------------------
6734 -- Fully_Conformant_Expressions --
6735 ----------------------------------
6737 function Fully_Conformant_Expressions
6738 (Given_E1 : Node_Id;
6739 Given_E2 : Node_Id) return Boolean
6741 E1 : constant Node_Id := Original_Node (Given_E1);
6742 E2 : constant Node_Id := Original_Node (Given_E2);
6743 -- We always test conformance on original nodes, since it is possible
6744 -- for analysis and/or expansion to make things look as though they
6745 -- conform when they do not, e.g. by converting 1+2 into 3.
6747 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
6748 renames Fully_Conformant_Expressions;
6750 function FCL (L1, L2 : List_Id) return Boolean;
6751 -- Compare elements of two lists for conformance. Elements have to
6752 -- be conformant, and actuals inserted as default parameters do not
6753 -- match explicit actuals with the same value.
6755 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
6756 -- Compare an operator node with a function call
6762 function FCL (L1, L2 : List_Id) return Boolean is
6766 if L1 = No_List then
6772 if L2 = No_List then
6778 -- Compare two lists, skipping rewrite insertions (we want to
6779 -- compare the original trees, not the expanded versions!)
6782 if Is_Rewrite_Insertion (N1) then
6784 elsif Is_Rewrite_Insertion (N2) then
6790 elsif not FCE (N1, N2) then
6803 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
6804 Actuals : constant List_Id := Parameter_Associations (Call_Node);
6809 or else Entity (Op_Node) /= Entity (Name (Call_Node))
6814 Act := First (Actuals);
6816 if Nkind (Op_Node) in N_Binary_Op then
6817 if not FCE (Left_Opnd (Op_Node), Act) then
6824 return Present (Act)
6825 and then FCE (Right_Opnd (Op_Node), Act)
6826 and then No (Next (Act));
6830 -- Start of processing for Fully_Conformant_Expressions
6833 -- Non-conformant if paren count does not match. Note: if some idiot
6834 -- complains that we don't do this right for more than 3 levels of
6835 -- parentheses, they will be treated with the respect they deserve!
6837 if Paren_Count (E1) /= Paren_Count (E2) then
6840 -- If same entities are referenced, then they are conformant even if
6841 -- they have different forms (RM 8.3.1(19-20)).
6843 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
6844 if Present (Entity (E1)) then
6845 return Entity (E1) = Entity (E2)
6846 or else (Chars (Entity (E1)) = Chars (Entity (E2))
6847 and then Ekind (Entity (E1)) = E_Discriminant
6848 and then Ekind (Entity (E2)) = E_In_Parameter);
6850 elsif Nkind (E1) = N_Expanded_Name
6851 and then Nkind (E2) = N_Expanded_Name
6852 and then Nkind (Selector_Name (E1)) = N_Character_Literal
6853 and then Nkind (Selector_Name (E2)) = N_Character_Literal
6855 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
6858 -- Identifiers in component associations don't always have
6859 -- entities, but their names must conform.
6861 return Nkind (E1) = N_Identifier
6862 and then Nkind (E2) = N_Identifier
6863 and then Chars (E1) = Chars (E2);
6866 elsif Nkind (E1) = N_Character_Literal
6867 and then Nkind (E2) = N_Expanded_Name
6869 return Nkind (Selector_Name (E2)) = N_Character_Literal
6870 and then Chars (E1) = Chars (Selector_Name (E2));
6872 elsif Nkind (E2) = N_Character_Literal
6873 and then Nkind (E1) = N_Expanded_Name
6875 return Nkind (Selector_Name (E1)) = N_Character_Literal
6876 and then Chars (E2) = Chars (Selector_Name (E1));
6878 elsif Nkind (E1) in N_Op
6879 and then Nkind (E2) = N_Function_Call
6881 return FCO (E1, E2);
6883 elsif Nkind (E2) in N_Op
6884 and then Nkind (E1) = N_Function_Call
6886 return FCO (E2, E1);
6888 -- Otherwise we must have the same syntactic entity
6890 elsif Nkind (E1) /= Nkind (E2) then
6893 -- At this point, we specialize by node type
6900 FCL (Expressions (E1), Expressions (E2))
6902 FCL (Component_Associations (E1),
6903 Component_Associations (E2));
6906 if Nkind (Expression (E1)) = N_Qualified_Expression
6908 Nkind (Expression (E2)) = N_Qualified_Expression
6910 return FCE (Expression (E1), Expression (E2));
6912 -- Check that the subtype marks and any constraints
6917 Indic1 : constant Node_Id := Expression (E1);
6918 Indic2 : constant Node_Id := Expression (E2);
6923 if Nkind (Indic1) /= N_Subtype_Indication then
6925 Nkind (Indic2) /= N_Subtype_Indication
6926 and then Entity (Indic1) = Entity (Indic2);
6928 elsif Nkind (Indic2) /= N_Subtype_Indication then
6930 Nkind (Indic1) /= N_Subtype_Indication
6931 and then Entity (Indic1) = Entity (Indic2);
6934 if Entity (Subtype_Mark (Indic1)) /=
6935 Entity (Subtype_Mark (Indic2))
6940 Elt1 := First (Constraints (Constraint (Indic1)));
6941 Elt2 := First (Constraints (Constraint (Indic2)));
6942 while Present (Elt1) and then Present (Elt2) loop
6943 if not FCE (Elt1, Elt2) then
6956 when N_Attribute_Reference =>
6958 Attribute_Name (E1) = Attribute_Name (E2)
6959 and then FCL (Expressions (E1), Expressions (E2));
6963 Entity (E1) = Entity (E2)
6964 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
6965 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
6967 when N_Short_Circuit | N_Membership_Test =>
6969 FCE (Left_Opnd (E1), Left_Opnd (E2))
6971 FCE (Right_Opnd (E1), Right_Opnd (E2));
6973 when N_Case_Expression =>
6979 if not FCE (Expression (E1), Expression (E2)) then
6983 Alt1 := First (Alternatives (E1));
6984 Alt2 := First (Alternatives (E2));
6986 if Present (Alt1) /= Present (Alt2) then
6988 elsif No (Alt1) then
6992 if not FCE (Expression (Alt1), Expression (Alt2))
6993 or else not FCL (Discrete_Choices (Alt1),
6994 Discrete_Choices (Alt2))
7005 when N_Character_Literal =>
7007 Char_Literal_Value (E1) = Char_Literal_Value (E2);
7009 when N_Component_Association =>
7011 FCL (Choices (E1), Choices (E2))
7013 FCE (Expression (E1), Expression (E2));
7015 when N_Conditional_Expression =>
7017 FCL (Expressions (E1), Expressions (E2));
7019 when N_Explicit_Dereference =>
7021 FCE (Prefix (E1), Prefix (E2));
7023 when N_Extension_Aggregate =>
7025 FCL (Expressions (E1), Expressions (E2))
7026 and then Null_Record_Present (E1) =
7027 Null_Record_Present (E2)
7028 and then FCL (Component_Associations (E1),
7029 Component_Associations (E2));
7031 when N_Function_Call =>
7033 FCE (Name (E1), Name (E2))
7035 FCL (Parameter_Associations (E1),
7036 Parameter_Associations (E2));
7038 when N_Indexed_Component =>
7040 FCE (Prefix (E1), Prefix (E2))
7042 FCL (Expressions (E1), Expressions (E2));
7044 when N_Integer_Literal =>
7045 return (Intval (E1) = Intval (E2));
7050 when N_Operator_Symbol =>
7052 Chars (E1) = Chars (E2);
7054 when N_Others_Choice =>
7057 when N_Parameter_Association =>
7059 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
7060 and then FCE (Explicit_Actual_Parameter (E1),
7061 Explicit_Actual_Parameter (E2));
7063 when N_Qualified_Expression =>
7065 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
7067 FCE (Expression (E1), Expression (E2));
7069 when N_Quantified_Expression =>
7070 if not FCE (Condition (E1), Condition (E2)) then
7074 if Present (Loop_Parameter_Specification (E1))
7075 and then Present (Loop_Parameter_Specification (E2))
7078 L1 : constant Node_Id :=
7079 Loop_Parameter_Specification (E1);
7080 L2 : constant Node_Id :=
7081 Loop_Parameter_Specification (E2);
7085 Reverse_Present (L1) = Reverse_Present (L2)
7087 FCE (Defining_Identifier (L1),
7088 Defining_Identifier (L2))
7090 FCE (Discrete_Subtype_Definition (L1),
7091 Discrete_Subtype_Definition (L2));
7094 else -- quantified expression with an iterator
7096 I1 : constant Node_Id := Iterator_Specification (E1);
7097 I2 : constant Node_Id := Iterator_Specification (E2);
7101 FCE (Defining_Identifier (I1),
7102 Defining_Identifier (I2))
7104 Of_Present (I1) = Of_Present (I2)
7106 Reverse_Present (I1) = Reverse_Present (I2)
7107 and then FCE (Name (I1), Name (I2))
7108 and then FCE (Subtype_Indication (I1),
7109 Subtype_Indication (I2));
7115 FCE (Low_Bound (E1), Low_Bound (E2))
7117 FCE (High_Bound (E1), High_Bound (E2));
7119 when N_Real_Literal =>
7120 return (Realval (E1) = Realval (E2));
7122 when N_Selected_Component =>
7124 FCE (Prefix (E1), Prefix (E2))
7126 FCE (Selector_Name (E1), Selector_Name (E2));
7130 FCE (Prefix (E1), Prefix (E2))
7132 FCE (Discrete_Range (E1), Discrete_Range (E2));
7134 when N_String_Literal =>
7136 S1 : constant String_Id := Strval (E1);
7137 S2 : constant String_Id := Strval (E2);
7138 L1 : constant Nat := String_Length (S1);
7139 L2 : constant Nat := String_Length (S2);
7146 for J in 1 .. L1 loop
7147 if Get_String_Char (S1, J) /=
7148 Get_String_Char (S2, J)
7158 when N_Type_Conversion =>
7160 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
7162 FCE (Expression (E1), Expression (E2));
7166 Entity (E1) = Entity (E2)
7168 FCE (Right_Opnd (E1), Right_Opnd (E2));
7170 when N_Unchecked_Type_Conversion =>
7172 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
7174 FCE (Expression (E1), Expression (E2));
7176 -- All other node types cannot appear in this context. Strictly
7177 -- we should raise a fatal internal error. Instead we just ignore
7178 -- the nodes. This means that if anyone makes a mistake in the
7179 -- expander and mucks an expression tree irretrievably, the
7180 -- result will be a failure to detect a (probably very obscure)
7181 -- case of non-conformance, which is better than bombing on some
7182 -- case where two expressions do in fact conform.
7189 end Fully_Conformant_Expressions;
7191 ----------------------------------------
7192 -- Fully_Conformant_Discrete_Subtypes --
7193 ----------------------------------------
7195 function Fully_Conformant_Discrete_Subtypes
7196 (Given_S1 : Node_Id;
7197 Given_S2 : Node_Id) return Boolean
7199 S1 : constant Node_Id := Original_Node (Given_S1);
7200 S2 : constant Node_Id := Original_Node (Given_S2);
7202 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
7203 -- Special-case for a bound given by a discriminant, which in the body
7204 -- is replaced with the discriminal of the enclosing type.
7206 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
7207 -- Check both bounds
7209 -----------------------
7210 -- Conforming_Bounds --
7211 -----------------------
7213 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
7215 if Is_Entity_Name (B1)
7216 and then Is_Entity_Name (B2)
7217 and then Ekind (Entity (B1)) = E_Discriminant
7219 return Chars (B1) = Chars (B2);
7222 return Fully_Conformant_Expressions (B1, B2);
7224 end Conforming_Bounds;
7226 -----------------------
7227 -- Conforming_Ranges --
7228 -----------------------
7230 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
7233 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
7235 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
7236 end Conforming_Ranges;
7238 -- Start of processing for Fully_Conformant_Discrete_Subtypes
7241 if Nkind (S1) /= Nkind (S2) then
7244 elsif Is_Entity_Name (S1) then
7245 return Entity (S1) = Entity (S2);
7247 elsif Nkind (S1) = N_Range then
7248 return Conforming_Ranges (S1, S2);
7250 elsif Nkind (S1) = N_Subtype_Indication then
7252 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
7255 (Range_Expression (Constraint (S1)),
7256 Range_Expression (Constraint (S2)));
7260 end Fully_Conformant_Discrete_Subtypes;
7262 --------------------
7263 -- Install_Entity --
7264 --------------------
7266 procedure Install_Entity (E : Entity_Id) is
7267 Prev : constant Entity_Id := Current_Entity (E);
7269 Set_Is_Immediately_Visible (E);
7270 Set_Current_Entity (E);
7271 Set_Homonym (E, Prev);
7274 ---------------------
7275 -- Install_Formals --
7276 ---------------------
7278 procedure Install_Formals (Id : Entity_Id) is
7281 F := First_Formal (Id);
7282 while Present (F) loop
7286 end Install_Formals;
7288 -----------------------------
7289 -- Is_Interface_Conformant --
7290 -----------------------------
7292 function Is_Interface_Conformant
7293 (Tagged_Type : Entity_Id;
7294 Iface_Prim : Entity_Id;
7295 Prim : Entity_Id) return Boolean
7297 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
7298 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
7300 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
7301 -- Return the controlling formal of Prim
7303 ------------------------
7304 -- Controlling_Formal --
7305 ------------------------
7307 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
7308 E : Entity_Id := First_Entity (Prim);
7311 while Present (E) loop
7312 if Is_Formal (E) and then Is_Controlling_Formal (E) then
7320 end Controlling_Formal;
7324 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
7325 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
7327 -- Start of processing for Is_Interface_Conformant
7330 pragma Assert (Is_Subprogram (Iface_Prim)
7331 and then Is_Subprogram (Prim)
7332 and then Is_Dispatching_Operation (Iface_Prim)
7333 and then Is_Dispatching_Operation (Prim));
7335 pragma Assert (Is_Interface (Iface)
7336 or else (Present (Alias (Iface_Prim))
7339 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
7341 if Prim = Iface_Prim
7342 or else not Is_Subprogram (Prim)
7343 or else Ekind (Prim) /= Ekind (Iface_Prim)
7344 or else not Is_Dispatching_Operation (Prim)
7345 or else Scope (Prim) /= Scope (Tagged_Type)
7347 or else Base_Type (Typ) /= Tagged_Type
7348 or else not Primitive_Names_Match (Iface_Prim, Prim)
7352 -- The mode of the controlling formals must match
7354 elsif Present (Iface_Ctrl_F)
7355 and then Present (Prim_Ctrl_F)
7356 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
7360 -- Case of a procedure, or a function whose result type matches the
7361 -- result type of the interface primitive, or a function that has no
7362 -- controlling result (I or access I).
7364 elsif Ekind (Iface_Prim) = E_Procedure
7365 or else Etype (Prim) = Etype (Iface_Prim)
7366 or else not Has_Controlling_Result (Prim)
7368 return Type_Conformant
7369 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
7371 -- Case of a function returning an interface, or an access to one.
7372 -- Check that the return types correspond.
7374 elsif Implements_Interface (Typ, Iface) then
7375 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
7377 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
7382 Type_Conformant (Prim, Iface_Prim,
7383 Skip_Controlling_Formals => True);
7389 end Is_Interface_Conformant;
7391 ---------------------------------
7392 -- Is_Non_Overriding_Operation --
7393 ---------------------------------
7395 function Is_Non_Overriding_Operation
7396 (Prev_E : Entity_Id;
7397 New_E : Entity_Id) return Boolean
7401 G_Typ : Entity_Id := Empty;
7403 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
7404 -- If F_Type is a derived type associated with a generic actual subtype,
7405 -- then return its Generic_Parent_Type attribute, else return Empty.
7407 function Types_Correspond
7408 (P_Type : Entity_Id;
7409 N_Type : Entity_Id) return Boolean;
7410 -- Returns true if and only if the types (or designated types in the
7411 -- case of anonymous access types) are the same or N_Type is derived
7412 -- directly or indirectly from P_Type.
7414 -----------------------------
7415 -- Get_Generic_Parent_Type --
7416 -----------------------------
7418 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
7424 if Is_Derived_Type (F_Typ)
7425 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
7427 -- The tree must be traversed to determine the parent subtype in
7428 -- the generic unit, which unfortunately isn't always available
7429 -- via semantic attributes. ??? (Note: The use of Original_Node
7430 -- is needed for cases where a full derived type has been
7433 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
7434 if Nkind (Defn) = N_Derived_Type_Definition then
7435 Indic := Subtype_Indication (Defn);
7437 if Nkind (Indic) = N_Subtype_Indication then
7438 G_Typ := Entity (Subtype_Mark (Indic));
7440 G_Typ := Entity (Indic);
7443 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
7444 and then Present (Generic_Parent_Type (Parent (G_Typ)))
7446 return Generic_Parent_Type (Parent (G_Typ));
7452 end Get_Generic_Parent_Type;
7454 ----------------------
7455 -- Types_Correspond --
7456 ----------------------
7458 function Types_Correspond
7459 (P_Type : Entity_Id;
7460 N_Type : Entity_Id) return Boolean
7462 Prev_Type : Entity_Id := Base_Type (P_Type);
7463 New_Type : Entity_Id := Base_Type (N_Type);
7466 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
7467 Prev_Type := Designated_Type (Prev_Type);
7470 if Ekind (New_Type) = E_Anonymous_Access_Type then
7471 New_Type := Designated_Type (New_Type);
7474 if Prev_Type = New_Type then
7477 elsif not Is_Class_Wide_Type (New_Type) then
7478 while Etype (New_Type) /= New_Type loop
7479 New_Type := Etype (New_Type);
7480 if New_Type = Prev_Type then
7486 end Types_Correspond;
7488 -- Start of processing for Is_Non_Overriding_Operation
7491 -- In the case where both operations are implicit derived subprograms
7492 -- then neither overrides the other. This can only occur in certain
7493 -- obscure cases (e.g., derivation from homographs created in a generic
7496 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
7499 elsif Ekind (Current_Scope) = E_Package
7500 and then Is_Generic_Instance (Current_Scope)
7501 and then In_Private_Part (Current_Scope)
7502 and then Comes_From_Source (New_E)
7504 -- We examine the formals and result type of the inherited operation,
7505 -- to determine whether their type is derived from (the instance of)
7506 -- a generic type. The first such formal or result type is the one
7509 Formal := First_Formal (Prev_E);
7510 while Present (Formal) loop
7511 F_Typ := Base_Type (Etype (Formal));
7513 if Ekind (F_Typ) = E_Anonymous_Access_Type then
7514 F_Typ := Designated_Type (F_Typ);
7517 G_Typ := Get_Generic_Parent_Type (F_Typ);
7518 exit when Present (G_Typ);
7520 Next_Formal (Formal);
7523 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
7524 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
7531 -- If the generic type is a private type, then the original operation
7532 -- was not overriding in the generic, because there was no primitive
7533 -- operation to override.
7535 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
7536 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
7537 N_Formal_Private_Type_Definition
7541 -- The generic parent type is the ancestor of a formal derived
7542 -- type declaration. We need to check whether it has a primitive
7543 -- operation that should be overridden by New_E in the generic.
7547 P_Formal : Entity_Id;
7548 N_Formal : Entity_Id;
7552 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
7555 while Present (Prim_Elt) loop
7556 P_Prim := Node (Prim_Elt);
7558 if Chars (P_Prim) = Chars (New_E)
7559 and then Ekind (P_Prim) = Ekind (New_E)
7561 P_Formal := First_Formal (P_Prim);
7562 N_Formal := First_Formal (New_E);
7563 while Present (P_Formal) and then Present (N_Formal) loop
7564 P_Typ := Etype (P_Formal);
7565 N_Typ := Etype (N_Formal);
7567 if not Types_Correspond (P_Typ, N_Typ) then
7571 Next_Entity (P_Formal);
7572 Next_Entity (N_Formal);
7575 -- Found a matching primitive operation belonging to the
7576 -- formal ancestor type, so the new subprogram is
7580 and then No (N_Formal)
7581 and then (Ekind (New_E) /= E_Function
7584 (Etype (P_Prim), Etype (New_E)))
7590 Next_Elmt (Prim_Elt);
7593 -- If no match found, then the new subprogram does not
7594 -- override in the generic (nor in the instance).
7602 end Is_Non_Overriding_Operation;
7604 -------------------------------------
7605 -- List_Inherited_Pre_Post_Aspects --
7606 -------------------------------------
7608 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
7610 if Opt.List_Inherited_Aspects
7611 and then (Is_Subprogram (E) or else Is_Generic_Subprogram (E))
7614 Inherited : constant Subprogram_List :=
7615 Inherited_Subprograms (E);
7619 for J in Inherited'Range loop
7620 P := Spec_PPC_List (Contract (Inherited (J)));
7622 while Present (P) loop
7623 Error_Msg_Sloc := Sloc (P);
7625 if Class_Present (P) and then not Split_PPC (P) then
7626 if Pragma_Name (P) = Name_Precondition then
7628 ("?info: & inherits `Pre''Class` aspect from #", E);
7631 ("?info: & inherits `Post''Class` aspect from #", E);
7635 P := Next_Pragma (P);
7640 end List_Inherited_Pre_Post_Aspects;
7642 ------------------------------
7643 -- Make_Inequality_Operator --
7644 ------------------------------
7646 -- S is the defining identifier of an equality operator. We build a
7647 -- subprogram declaration with the right signature. This operation is
7648 -- intrinsic, because it is always expanded as the negation of the
7649 -- call to the equality function.
7651 procedure Make_Inequality_Operator (S : Entity_Id) is
7652 Loc : constant Source_Ptr := Sloc (S);
7655 Op_Name : Entity_Id;
7657 FF : constant Entity_Id := First_Formal (S);
7658 NF : constant Entity_Id := Next_Formal (FF);
7661 -- Check that equality was properly defined, ignore call if not
7668 A : constant Entity_Id :=
7669 Make_Defining_Identifier (Sloc (FF),
7670 Chars => Chars (FF));
7672 B : constant Entity_Id :=
7673 Make_Defining_Identifier (Sloc (NF),
7674 Chars => Chars (NF));
7677 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
7679 Formals := New_List (
7680 Make_Parameter_Specification (Loc,
7681 Defining_Identifier => A,
7683 New_Reference_To (Etype (First_Formal (S)),
7684 Sloc (Etype (First_Formal (S))))),
7686 Make_Parameter_Specification (Loc,
7687 Defining_Identifier => B,
7689 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
7690 Sloc (Etype (Next_Formal (First_Formal (S)))))));
7693 Make_Subprogram_Declaration (Loc,
7695 Make_Function_Specification (Loc,
7696 Defining_Unit_Name => Op_Name,
7697 Parameter_Specifications => Formals,
7698 Result_Definition =>
7699 New_Reference_To (Standard_Boolean, Loc)));
7701 -- Insert inequality right after equality if it is explicit or after
7702 -- the derived type when implicit. These entities are created only
7703 -- for visibility purposes, and eventually replaced in the course of
7704 -- expansion, so they do not need to be attached to the tree and seen
7705 -- by the back-end. Keeping them internal also avoids spurious
7706 -- freezing problems. The declaration is inserted in the tree for
7707 -- analysis, and removed afterwards. If the equality operator comes
7708 -- from an explicit declaration, attach the inequality immediately
7709 -- after. Else the equality is inherited from a derived type
7710 -- declaration, so insert inequality after that declaration.
7712 if No (Alias (S)) then
7713 Insert_After (Unit_Declaration_Node (S), Decl);
7714 elsif Is_List_Member (Parent (S)) then
7715 Insert_After (Parent (S), Decl);
7717 Insert_After (Parent (Etype (First_Formal (S))), Decl);
7720 Mark_Rewrite_Insertion (Decl);
7721 Set_Is_Intrinsic_Subprogram (Op_Name);
7724 Set_Has_Completion (Op_Name);
7725 Set_Corresponding_Equality (Op_Name, S);
7726 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
7728 end Make_Inequality_Operator;
7730 ----------------------
7731 -- May_Need_Actuals --
7732 ----------------------
7734 procedure May_Need_Actuals (Fun : Entity_Id) is
7739 F := First_Formal (Fun);
7741 while Present (F) loop
7742 if No (Default_Value (F)) then
7750 Set_Needs_No_Actuals (Fun, B);
7751 end May_Need_Actuals;
7753 ---------------------
7754 -- Mode_Conformant --
7755 ---------------------
7757 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7760 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
7762 end Mode_Conformant;
7764 ---------------------------
7765 -- New_Overloaded_Entity --
7766 ---------------------------
7768 procedure New_Overloaded_Entity
7770 Derived_Type : Entity_Id := Empty)
7772 Overridden_Subp : Entity_Id := Empty;
7773 -- Set if the current scope has an operation that is type-conformant
7774 -- with S, and becomes hidden by S.
7776 Is_Primitive_Subp : Boolean;
7777 -- Set to True if the new subprogram is primitive
7780 -- Entity that S overrides
7782 Prev_Vis : Entity_Id := Empty;
7783 -- Predecessor of E in Homonym chain
7785 procedure Check_For_Primitive_Subprogram
7786 (Is_Primitive : out Boolean;
7787 Is_Overriding : Boolean := False);
7788 -- If the subprogram being analyzed is a primitive operation of the type
7789 -- of a formal or result, set the Has_Primitive_Operations flag on the
7790 -- type, and set Is_Primitive to True (otherwise set to False). Set the
7791 -- corresponding flag on the entity itself for later use.
7793 procedure Check_Synchronized_Overriding
7794 (Def_Id : Entity_Id;
7795 Overridden_Subp : out Entity_Id);
7796 -- First determine if Def_Id is an entry or a subprogram either defined
7797 -- in the scope of a task or protected type, or is a primitive of such
7798 -- a type. Check whether Def_Id overrides a subprogram of an interface
7799 -- implemented by the synchronized type, return the overridden entity
7802 function Is_Private_Declaration (E : Entity_Id) return Boolean;
7803 -- Check that E is declared in the private part of the current package,
7804 -- or in the package body, where it may hide a previous declaration.
7805 -- We can't use In_Private_Part by itself because this flag is also
7806 -- set when freezing entities, so we must examine the place of the
7807 -- declaration in the tree, and recognize wrapper packages as well.
7809 function Is_Overriding_Alias
7811 New_E : Entity_Id) return Boolean;
7812 -- Check whether new subprogram and old subprogram are both inherited
7813 -- from subprograms that have distinct dispatch table entries. This can
7814 -- occur with derivations from instances with accidental homonyms.
7815 -- The function is conservative given that the converse is only true
7816 -- within instances that contain accidental overloadings.
7818 ------------------------------------
7819 -- Check_For_Primitive_Subprogram --
7820 ------------------------------------
7822 procedure Check_For_Primitive_Subprogram
7823 (Is_Primitive : out Boolean;
7824 Is_Overriding : Boolean := False)
7830 function Visible_Part_Type (T : Entity_Id) return Boolean;
7831 -- Returns true if T is declared in the visible part of the current
7832 -- package scope; otherwise returns false. Assumes that T is declared
7835 procedure Check_Private_Overriding (T : Entity_Id);
7836 -- Checks that if a primitive abstract subprogram of a visible
7837 -- abstract type is declared in a private part, then it must override
7838 -- an abstract subprogram declared in the visible part. Also checks
7839 -- that if a primitive function with a controlling result is declared
7840 -- in a private part, then it must override a function declared in
7841 -- the visible part.
7843 ------------------------------
7844 -- Check_Private_Overriding --
7845 ------------------------------
7847 procedure Check_Private_Overriding (T : Entity_Id) is
7849 if Is_Package_Or_Generic_Package (Current_Scope)
7850 and then In_Private_Part (Current_Scope)
7851 and then Visible_Part_Type (T)
7852 and then not In_Instance
7854 if Is_Abstract_Type (T)
7855 and then Is_Abstract_Subprogram (S)
7856 and then (not Is_Overriding
7857 or else not Is_Abstract_Subprogram (E))
7860 ("abstract subprograms must be visible "
7861 & "(RM 3.9.3(10))!", S);
7863 elsif Ekind (S) = E_Function
7864 and then not Is_Overriding
7866 if Is_Tagged_Type (T)
7867 and then T = Base_Type (Etype (S))
7870 ("private function with tagged result must"
7871 & " override visible-part function", S);
7873 ("\move subprogram to the visible part"
7874 & " (RM 3.9.3(10))", S);
7876 -- AI05-0073: extend this test to the case of a function
7877 -- with a controlling access result.
7879 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
7880 and then Is_Tagged_Type (Designated_Type (Etype (S)))
7882 not Is_Class_Wide_Type (Designated_Type (Etype (S)))
7883 and then Ada_Version >= Ada_2012
7886 ("private function with controlling access result "
7887 & "must override visible-part function", S);
7889 ("\move subprogram to the visible part"
7890 & " (RM 3.9.3(10))", S);
7894 end Check_Private_Overriding;
7896 -----------------------
7897 -- Visible_Part_Type --
7898 -----------------------
7900 function Visible_Part_Type (T : Entity_Id) return Boolean is
7901 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
7905 -- If the entity is a private type, then it must be declared in a
7908 if Ekind (T) in Private_Kind then
7912 -- Otherwise, we traverse the visible part looking for its
7913 -- corresponding declaration. We cannot use the declaration
7914 -- node directly because in the private part the entity of a
7915 -- private type is the one in the full view, which does not
7916 -- indicate that it is the completion of something visible.
7918 N := First (Visible_Declarations (Specification (P)));
7919 while Present (N) loop
7920 if Nkind (N) = N_Full_Type_Declaration
7921 and then Present (Defining_Identifier (N))
7922 and then T = Defining_Identifier (N)
7926 elsif Nkind_In (N, N_Private_Type_Declaration,
7927 N_Private_Extension_Declaration)
7928 and then Present (Defining_Identifier (N))
7929 and then T = Full_View (Defining_Identifier (N))
7938 end Visible_Part_Type;
7940 -- Start of processing for Check_For_Primitive_Subprogram
7943 Is_Primitive := False;
7945 if not Comes_From_Source (S) then
7948 -- If subprogram is at library level, it is not primitive operation
7950 elsif Current_Scope = Standard_Standard then
7953 elsif (Is_Package_Or_Generic_Package (Current_Scope)
7954 and then not In_Package_Body (Current_Scope))
7955 or else Is_Overriding
7957 -- For function, check return type
7959 if Ekind (S) = E_Function then
7960 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
7961 F_Typ := Designated_Type (Etype (S));
7966 B_Typ := Base_Type (F_Typ);
7968 if Scope (B_Typ) = Current_Scope
7969 and then not Is_Class_Wide_Type (B_Typ)
7970 and then not Is_Generic_Type (B_Typ)
7972 Is_Primitive := True;
7973 Set_Has_Primitive_Operations (B_Typ);
7974 Set_Is_Primitive (S);
7975 Check_Private_Overriding (B_Typ);
7979 -- For all subprograms, check formals
7981 Formal := First_Formal (S);
7982 while Present (Formal) loop
7983 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
7984 F_Typ := Designated_Type (Etype (Formal));
7986 F_Typ := Etype (Formal);
7989 B_Typ := Base_Type (F_Typ);
7991 if Ekind (B_Typ) = E_Access_Subtype then
7992 B_Typ := Base_Type (B_Typ);
7995 if Scope (B_Typ) = Current_Scope
7996 and then not Is_Class_Wide_Type (B_Typ)
7997 and then not Is_Generic_Type (B_Typ)
7999 Is_Primitive := True;
8000 Set_Is_Primitive (S);
8001 Set_Has_Primitive_Operations (B_Typ);
8002 Check_Private_Overriding (B_Typ);
8005 Next_Formal (Formal);
8008 end Check_For_Primitive_Subprogram;
8010 -----------------------------------
8011 -- Check_Synchronized_Overriding --
8012 -----------------------------------
8014 procedure Check_Synchronized_Overriding
8015 (Def_Id : Entity_Id;
8016 Overridden_Subp : out Entity_Id)
8018 Ifaces_List : Elist_Id;
8022 function Matches_Prefixed_View_Profile
8023 (Prim_Params : List_Id;
8024 Iface_Params : List_Id) return Boolean;
8025 -- Determine whether a subprogram's parameter profile Prim_Params
8026 -- matches that of a potentially overridden interface subprogram
8027 -- Iface_Params. Also determine if the type of first parameter of
8028 -- Iface_Params is an implemented interface.
8030 -----------------------------------
8031 -- Matches_Prefixed_View_Profile --
8032 -----------------------------------
8034 function Matches_Prefixed_View_Profile
8035 (Prim_Params : List_Id;
8036 Iface_Params : List_Id) return Boolean
8038 Iface_Id : Entity_Id;
8039 Iface_Param : Node_Id;
8040 Iface_Typ : Entity_Id;
8041 Prim_Id : Entity_Id;
8042 Prim_Param : Node_Id;
8043 Prim_Typ : Entity_Id;
8045 function Is_Implemented
8046 (Ifaces_List : Elist_Id;
8047 Iface : Entity_Id) return Boolean;
8048 -- Determine if Iface is implemented by the current task or
8051 --------------------
8052 -- Is_Implemented --
8053 --------------------
8055 function Is_Implemented
8056 (Ifaces_List : Elist_Id;
8057 Iface : Entity_Id) return Boolean
8059 Iface_Elmt : Elmt_Id;
8062 Iface_Elmt := First_Elmt (Ifaces_List);
8063 while Present (Iface_Elmt) loop
8064 if Node (Iface_Elmt) = Iface then
8068 Next_Elmt (Iface_Elmt);
8074 -- Start of processing for Matches_Prefixed_View_Profile
8077 Iface_Param := First (Iface_Params);
8078 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
8080 if Is_Access_Type (Iface_Typ) then
8081 Iface_Typ := Designated_Type (Iface_Typ);
8084 Prim_Param := First (Prim_Params);
8086 -- The first parameter of the potentially overridden subprogram
8087 -- must be an interface implemented by Prim.
8089 if not Is_Interface (Iface_Typ)
8090 or else not Is_Implemented (Ifaces_List, Iface_Typ)
8095 -- The checks on the object parameters are done, move onto the
8096 -- rest of the parameters.
8098 if not In_Scope then
8099 Prim_Param := Next (Prim_Param);
8102 Iface_Param := Next (Iface_Param);
8103 while Present (Iface_Param) and then Present (Prim_Param) loop
8104 Iface_Id := Defining_Identifier (Iface_Param);
8105 Iface_Typ := Find_Parameter_Type (Iface_Param);
8107 Prim_Id := Defining_Identifier (Prim_Param);
8108 Prim_Typ := Find_Parameter_Type (Prim_Param);
8110 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
8111 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
8112 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
8114 Iface_Typ := Designated_Type (Iface_Typ);
8115 Prim_Typ := Designated_Type (Prim_Typ);
8118 -- Case of multiple interface types inside a parameter profile
8120 -- (Obj_Param : in out Iface; ...; Param : Iface)
8122 -- If the interface type is implemented, then the matching type
8123 -- in the primitive should be the implementing record type.
8125 if Ekind (Iface_Typ) = E_Record_Type
8126 and then Is_Interface (Iface_Typ)
8127 and then Is_Implemented (Ifaces_List, Iface_Typ)
8129 if Prim_Typ /= Typ then
8133 -- The two parameters must be both mode and subtype conformant
8135 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
8137 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
8146 -- One of the two lists contains more parameters than the other
8148 if Present (Iface_Param) or else Present (Prim_Param) then
8153 end Matches_Prefixed_View_Profile;
8155 -- Start of processing for Check_Synchronized_Overriding
8158 Overridden_Subp := Empty;
8160 -- Def_Id must be an entry or a subprogram. We should skip predefined
8161 -- primitives internally generated by the frontend; however at this
8162 -- stage predefined primitives are still not fully decorated. As a
8163 -- minor optimization we skip here internally generated subprograms.
8165 if (Ekind (Def_Id) /= E_Entry
8166 and then Ekind (Def_Id) /= E_Function
8167 and then Ekind (Def_Id) /= E_Procedure)
8168 or else not Comes_From_Source (Def_Id)
8173 -- Search for the concurrent declaration since it contains the list
8174 -- of all implemented interfaces. In this case, the subprogram is
8175 -- declared within the scope of a protected or a task type.
8177 if Present (Scope (Def_Id))
8178 and then Is_Concurrent_Type (Scope (Def_Id))
8179 and then not Is_Generic_Actual_Type (Scope (Def_Id))
8181 Typ := Scope (Def_Id);
8184 -- The enclosing scope is not a synchronized type and the subprogram
8187 elsif No (First_Formal (Def_Id)) then
8190 -- The subprogram has formals and hence it may be a primitive of a
8194 Typ := Etype (First_Formal (Def_Id));
8196 if Is_Access_Type (Typ) then
8197 Typ := Directly_Designated_Type (Typ);
8200 if Is_Concurrent_Type (Typ)
8201 and then not Is_Generic_Actual_Type (Typ)
8205 -- This case occurs when the concurrent type is declared within
8206 -- a generic unit. As a result the corresponding record has been
8207 -- built and used as the type of the first formal, we just have
8208 -- to retrieve the corresponding concurrent type.
8210 elsif Is_Concurrent_Record_Type (Typ)
8211 and then not Is_Class_Wide_Type (Typ)
8212 and then Present (Corresponding_Concurrent_Type (Typ))
8214 Typ := Corresponding_Concurrent_Type (Typ);
8222 -- There is no overriding to check if is an inherited operation in a
8223 -- type derivation on for a generic actual.
8225 Collect_Interfaces (Typ, Ifaces_List);
8227 if Is_Empty_Elmt_List (Ifaces_List) then
8231 -- Determine whether entry or subprogram Def_Id overrides a primitive
8232 -- operation that belongs to one of the interfaces in Ifaces_List.
8235 Candidate : Entity_Id := Empty;
8236 Hom : Entity_Id := Empty;
8237 Iface_Typ : Entity_Id;
8238 Subp : Entity_Id := Empty;
8241 -- Traverse the homonym chain, looking for a potentially
8242 -- overridden subprogram that belongs to an implemented
8245 Hom := Current_Entity_In_Scope (Def_Id);
8246 while Present (Hom) loop
8250 or else not Is_Overloadable (Subp)
8251 or else not Is_Primitive (Subp)
8252 or else not Is_Dispatching_Operation (Subp)
8253 or else not Present (Find_Dispatching_Type (Subp))
8254 or else not Is_Interface (Find_Dispatching_Type (Subp))
8258 -- Entries and procedures can override abstract or null
8259 -- interface procedures.
8261 elsif (Ekind (Def_Id) = E_Procedure
8262 or else Ekind (Def_Id) = E_Entry)
8263 and then Ekind (Subp) = E_Procedure
8264 and then Matches_Prefixed_View_Profile
8265 (Parameter_Specifications (Parent (Def_Id)),
8266 Parameter_Specifications (Parent (Subp)))
8270 -- For an overridden subprogram Subp, check whether the mode
8271 -- of its first parameter is correct depending on the kind
8272 -- of synchronized type.
8275 Formal : constant Node_Id := First_Formal (Candidate);
8278 -- In order for an entry or a protected procedure to
8279 -- override, the first parameter of the overridden
8280 -- routine must be of mode "out", "in out" or
8281 -- access-to-variable.
8283 if (Ekind (Candidate) = E_Entry
8284 or else Ekind (Candidate) = E_Procedure)
8285 and then Is_Protected_Type (Typ)
8286 and then Ekind (Formal) /= E_In_Out_Parameter
8287 and then Ekind (Formal) /= E_Out_Parameter
8288 and then Nkind (Parameter_Type (Parent (Formal)))
8289 /= N_Access_Definition
8293 -- All other cases are OK since a task entry or routine
8294 -- does not have a restriction on the mode of the first
8295 -- parameter of the overridden interface routine.
8298 Overridden_Subp := Candidate;
8303 -- Functions can override abstract interface functions
8305 elsif Ekind (Def_Id) = E_Function
8306 and then Ekind (Subp) = E_Function
8307 and then Matches_Prefixed_View_Profile
8308 (Parameter_Specifications (Parent (Def_Id)),
8309 Parameter_Specifications (Parent (Subp)))
8310 and then Etype (Result_Definition (Parent (Def_Id))) =
8311 Etype (Result_Definition (Parent (Subp)))
8313 Overridden_Subp := Subp;
8317 Hom := Homonym (Hom);
8320 -- After examining all candidates for overriding, we are left with
8321 -- the best match which is a mode incompatible interface routine.
8322 -- Do not emit an error if the Expander is active since this error
8323 -- will be detected later on after all concurrent types are
8324 -- expanded and all wrappers are built. This check is meant for
8325 -- spec-only compilations.
8327 if Present (Candidate) and then not Expander_Active then
8329 Find_Parameter_Type (Parent (First_Formal (Candidate)));
8331 -- Def_Id is primitive of a protected type, declared inside the
8332 -- type, and the candidate is primitive of a limited or
8333 -- synchronized interface.
8336 and then Is_Protected_Type (Typ)
8338 (Is_Limited_Interface (Iface_Typ)
8339 or else Is_Protected_Interface (Iface_Typ)
8340 or else Is_Synchronized_Interface (Iface_Typ)
8341 or else Is_Task_Interface (Iface_Typ))
8343 Error_Msg_PT (Parent (Typ), Candidate);
8347 Overridden_Subp := Candidate;
8350 end Check_Synchronized_Overriding;
8352 ----------------------------
8353 -- Is_Private_Declaration --
8354 ----------------------------
8356 function Is_Private_Declaration (E : Entity_Id) return Boolean is
8357 Priv_Decls : List_Id;
8358 Decl : constant Node_Id := Unit_Declaration_Node (E);
8361 if Is_Package_Or_Generic_Package (Current_Scope)
8362 and then In_Private_Part (Current_Scope)
8365 Private_Declarations (
8366 Specification (Unit_Declaration_Node (Current_Scope)));
8368 return In_Package_Body (Current_Scope)
8370 (Is_List_Member (Decl)
8371 and then List_Containing (Decl) = Priv_Decls)
8372 or else (Nkind (Parent (Decl)) = N_Package_Specification
8375 (Defining_Entity (Parent (Decl)))
8376 and then List_Containing (Parent (Parent (Decl)))
8381 end Is_Private_Declaration;
8383 --------------------------
8384 -- Is_Overriding_Alias --
8385 --------------------------
8387 function Is_Overriding_Alias
8389 New_E : Entity_Id) return Boolean
8391 AO : constant Entity_Id := Alias (Old_E);
8392 AN : constant Entity_Id := Alias (New_E);
8395 return Scope (AO) /= Scope (AN)
8396 or else No (DTC_Entity (AO))
8397 or else No (DTC_Entity (AN))
8398 or else DT_Position (AO) = DT_Position (AN);
8399 end Is_Overriding_Alias;
8401 -- Start of processing for New_Overloaded_Entity
8404 -- We need to look for an entity that S may override. This must be a
8405 -- homonym in the current scope, so we look for the first homonym of
8406 -- S in the current scope as the starting point for the search.
8408 E := Current_Entity_In_Scope (S);
8410 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
8411 -- They are directly added to the list of primitive operations of
8412 -- Derived_Type, unless this is a rederivation in the private part
8413 -- of an operation that was already derived in the visible part of
8414 -- the current package.
8416 if Ada_Version >= Ada_2005
8417 and then Present (Derived_Type)
8418 and then Present (Alias (S))
8419 and then Is_Dispatching_Operation (Alias (S))
8420 and then Present (Find_Dispatching_Type (Alias (S)))
8421 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
8423 -- For private types, when the full-view is processed we propagate to
8424 -- the full view the non-overridden entities whose attribute "alias"
8425 -- references an interface primitive. These entities were added by
8426 -- Derive_Subprograms to ensure that interface primitives are
8429 -- Inside_Freeze_Actions is non zero when S corresponds with an
8430 -- internal entity that links an interface primitive with its
8431 -- covering primitive through attribute Interface_Alias (see
8432 -- Add_Internal_Interface_Entities).
8434 if Inside_Freezing_Actions = 0
8435 and then Is_Package_Or_Generic_Package (Current_Scope)
8436 and then In_Private_Part (Current_Scope)
8437 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
8438 and then Nkind (Parent (S)) = N_Full_Type_Declaration
8439 and then Full_View (Defining_Identifier (Parent (E)))
8440 = Defining_Identifier (Parent (S))
8441 and then Alias (E) = Alias (S)
8443 Check_Operation_From_Private_View (S, E);
8444 Set_Is_Dispatching_Operation (S);
8449 Enter_Overloaded_Entity (S);
8450 Check_Dispatching_Operation (S, Empty);
8451 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8457 -- If there is no homonym then this is definitely not overriding
8460 Enter_Overloaded_Entity (S);
8461 Check_Dispatching_Operation (S, Empty);
8462 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8464 -- If subprogram has an explicit declaration, check whether it
8465 -- has an overriding indicator.
8467 if Comes_From_Source (S) then
8468 Check_Synchronized_Overriding (S, Overridden_Subp);
8470 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
8471 -- it may have overridden some hidden inherited primitive. Update
8472 -- Overridden_Subp to avoid spurious errors when checking the
8473 -- overriding indicator.
8475 if Ada_Version >= Ada_2012
8476 and then No (Overridden_Subp)
8477 and then Is_Dispatching_Operation (S)
8478 and then Present (Overridden_Operation (S))
8480 Overridden_Subp := Overridden_Operation (S);
8483 Check_Overriding_Indicator
8484 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8487 -- If there is a homonym that is not overloadable, then we have an
8488 -- error, except for the special cases checked explicitly below.
8490 elsif not Is_Overloadable (E) then
8492 -- Check for spurious conflict produced by a subprogram that has the
8493 -- same name as that of the enclosing generic package. The conflict
8494 -- occurs within an instance, between the subprogram and the renaming
8495 -- declaration for the package. After the subprogram, the package
8496 -- renaming declaration becomes hidden.
8498 if Ekind (E) = E_Package
8499 and then Present (Renamed_Object (E))
8500 and then Renamed_Object (E) = Current_Scope
8501 and then Nkind (Parent (Renamed_Object (E))) =
8502 N_Package_Specification
8503 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
8506 Set_Is_Immediately_Visible (E, False);
8507 Enter_Overloaded_Entity (S);
8508 Set_Homonym (S, Homonym (E));
8509 Check_Dispatching_Operation (S, Empty);
8510 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
8512 -- If the subprogram is implicit it is hidden by the previous
8513 -- declaration. However if it is dispatching, it must appear in the
8514 -- dispatch table anyway, because it can be dispatched to even if it
8515 -- cannot be called directly.
8517 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
8518 Set_Scope (S, Current_Scope);
8520 if Is_Dispatching_Operation (Alias (S)) then
8521 Check_Dispatching_Operation (S, Empty);
8527 Error_Msg_Sloc := Sloc (E);
8529 -- Generate message, with useful additional warning if in generic
8531 if Is_Generic_Unit (E) then
8532 Error_Msg_N ("previous generic unit cannot be overloaded", S);
8533 Error_Msg_N ("\& conflicts with declaration#", S);
8535 Error_Msg_N ("& conflicts with declaration#", S);
8541 -- E exists and is overloadable
8544 Check_Synchronized_Overriding (S, Overridden_Subp);
8546 -- Loop through E and its homonyms to determine if any of them is
8547 -- the candidate for overriding by S.
8549 while Present (E) loop
8551 -- Definitely not interesting if not in the current scope
8553 if Scope (E) /= Current_Scope then
8556 -- Ada 2012 (AI05-0165): For internally generated bodies of
8557 -- null procedures locate the internally generated spec. We
8558 -- enforce mode conformance since a tagged type may inherit
8559 -- from interfaces several null primitives which differ only
8560 -- in the mode of the formals.
8562 elsif not Comes_From_Source (S)
8563 and then Is_Null_Procedure (S)
8564 and then not Mode_Conformant (E, S)
8568 -- Check if we have type conformance
8570 elsif Type_Conformant (E, S) then
8572 -- If the old and new entities have the same profile and one
8573 -- is not the body of the other, then this is an error, unless
8574 -- one of them is implicitly declared.
8576 -- There are some cases when both can be implicit, for example
8577 -- when both a literal and a function that overrides it are
8578 -- inherited in a derivation, or when an inherited operation
8579 -- of a tagged full type overrides the inherited operation of
8580 -- a private extension. Ada 83 had a special rule for the
8581 -- literal case. In Ada95, the later implicit operation hides
8582 -- the former, and the literal is always the former. In the
8583 -- odd case where both are derived operations declared at the
8584 -- same point, both operations should be declared, and in that
8585 -- case we bypass the following test and proceed to the next
8586 -- part. This can only occur for certain obscure cases in
8587 -- instances, when an operation on a type derived from a formal
8588 -- private type does not override a homograph inherited from
8589 -- the actual. In subsequent derivations of such a type, the
8590 -- DT positions of these operations remain distinct, if they
8593 if Present (Alias (S))
8594 and then (No (Alias (E))
8595 or else Comes_From_Source (E)
8596 or else Is_Abstract_Subprogram (S)
8598 (Is_Dispatching_Operation (E)
8599 and then Is_Overriding_Alias (E, S)))
8600 and then Ekind (E) /= E_Enumeration_Literal
8602 -- When an derived operation is overloaded it may be due to
8603 -- the fact that the full view of a private extension
8604 -- re-inherits. It has to be dealt with.
8606 if Is_Package_Or_Generic_Package (Current_Scope)
8607 and then In_Private_Part (Current_Scope)
8609 Check_Operation_From_Private_View (S, E);
8612 -- In any case the implicit operation remains hidden by the
8613 -- existing declaration, which is overriding. Indicate that
8614 -- E overrides the operation from which S is inherited.
8616 if Present (Alias (S)) then
8617 Set_Overridden_Operation (E, Alias (S));
8619 Set_Overridden_Operation (E, S);
8622 if Comes_From_Source (E) then
8623 Check_Overriding_Indicator (E, S, Is_Primitive => False);
8628 -- Within an instance, the renaming declarations for actual
8629 -- subprograms may become ambiguous, but they do not hide each
8632 elsif Ekind (E) /= E_Entry
8633 and then not Comes_From_Source (E)
8634 and then not Is_Generic_Instance (E)
8635 and then (Present (Alias (E))
8636 or else Is_Intrinsic_Subprogram (E))
8637 and then (not In_Instance
8638 or else No (Parent (E))
8639 or else Nkind (Unit_Declaration_Node (E)) /=
8640 N_Subprogram_Renaming_Declaration)
8642 -- A subprogram child unit is not allowed to override an
8643 -- inherited subprogram (10.1.1(20)).
8645 if Is_Child_Unit (S) then
8647 ("child unit overrides inherited subprogram in parent",
8652 if Is_Non_Overriding_Operation (E, S) then
8653 Enter_Overloaded_Entity (S);
8655 if No (Derived_Type)
8656 or else Is_Tagged_Type (Derived_Type)
8658 Check_Dispatching_Operation (S, Empty);
8664 -- E is a derived operation or an internal operator which
8665 -- is being overridden. Remove E from further visibility.
8666 -- Furthermore, if E is a dispatching operation, it must be
8667 -- replaced in the list of primitive operations of its type
8668 -- (see Override_Dispatching_Operation).
8670 Overridden_Subp := E;
8676 Prev := First_Entity (Current_Scope);
8677 while Present (Prev)
8678 and then Next_Entity (Prev) /= E
8683 -- It is possible for E to be in the current scope and
8684 -- yet not in the entity chain. This can only occur in a
8685 -- generic context where E is an implicit concatenation
8686 -- in the formal part, because in a generic body the
8687 -- entity chain starts with the formals.
8690 (Present (Prev) or else Chars (E) = Name_Op_Concat);
8692 -- E must be removed both from the entity_list of the
8693 -- current scope, and from the visibility chain
8695 if Debug_Flag_E then
8696 Write_Str ("Override implicit operation ");
8697 Write_Int (Int (E));
8701 -- If E is a predefined concatenation, it stands for four
8702 -- different operations. As a result, a single explicit
8703 -- declaration does not hide it. In a possible ambiguous
8704 -- situation, Disambiguate chooses the user-defined op,
8705 -- so it is correct to retain the previous internal one.
8707 if Chars (E) /= Name_Op_Concat
8708 or else Ekind (E) /= E_Operator
8710 -- For nondispatching derived operations that are
8711 -- overridden by a subprogram declared in the private
8712 -- part of a package, we retain the derived subprogram
8713 -- but mark it as not immediately visible. If the
8714 -- derived operation was declared in the visible part
8715 -- then this ensures that it will still be visible
8716 -- outside the package with the proper signature
8717 -- (calls from outside must also be directed to this
8718 -- version rather than the overriding one, unlike the
8719 -- dispatching case). Calls from inside the package
8720 -- will still resolve to the overriding subprogram
8721 -- since the derived one is marked as not visible
8722 -- within the package.
8724 -- If the private operation is dispatching, we achieve
8725 -- the overriding by keeping the implicit operation
8726 -- but setting its alias to be the overriding one. In
8727 -- this fashion the proper body is executed in all
8728 -- cases, but the original signature is used outside
8731 -- If the overriding is not in the private part, we
8732 -- remove the implicit operation altogether.
8734 if Is_Private_Declaration (S) then
8735 if not Is_Dispatching_Operation (E) then
8736 Set_Is_Immediately_Visible (E, False);
8738 -- Work done in Override_Dispatching_Operation,
8739 -- so nothing else need to be done here.
8745 -- Find predecessor of E in Homonym chain
8747 if E = Current_Entity (E) then
8750 Prev_Vis := Current_Entity (E);
8751 while Homonym (Prev_Vis) /= E loop
8752 Prev_Vis := Homonym (Prev_Vis);
8756 if Prev_Vis /= Empty then
8758 -- Skip E in the visibility chain
8760 Set_Homonym (Prev_Vis, Homonym (E));
8763 Set_Name_Entity_Id (Chars (E), Homonym (E));
8766 Set_Next_Entity (Prev, Next_Entity (E));
8768 if No (Next_Entity (Prev)) then
8769 Set_Last_Entity (Current_Scope, Prev);
8774 Enter_Overloaded_Entity (S);
8776 -- For entities generated by Derive_Subprograms the
8777 -- overridden operation is the inherited primitive
8778 -- (which is available through the attribute alias).
8780 if not (Comes_From_Source (E))
8781 and then Is_Dispatching_Operation (E)
8782 and then Find_Dispatching_Type (E) =
8783 Find_Dispatching_Type (S)
8784 and then Present (Alias (E))
8785 and then Comes_From_Source (Alias (E))
8787 Set_Overridden_Operation (S, Alias (E));
8789 -- Normal case of setting entity as overridden
8791 -- Note: Static_Initialization and Overridden_Operation
8792 -- attributes use the same field in subprogram entities.
8793 -- Static_Initialization is only defined for internal
8794 -- initialization procedures, where Overridden_Operation
8795 -- is irrelevant. Therefore the setting of this attribute
8796 -- must check whether the target is an init_proc.
8798 elsif not Is_Init_Proc (S) then
8799 Set_Overridden_Operation (S, E);
8802 Check_Overriding_Indicator (S, E, Is_Primitive => True);
8804 -- If S is a user-defined subprogram or a null procedure
8805 -- expanded to override an inherited null procedure, or a
8806 -- predefined dispatching primitive then indicate that E
8807 -- overrides the operation from which S is inherited.
8809 if Comes_From_Source (S)
8811 (Present (Parent (S))
8813 Nkind (Parent (S)) = N_Procedure_Specification
8815 Null_Present (Parent (S)))
8817 (Present (Alias (E))
8819 Is_Predefined_Dispatching_Operation (Alias (E)))
8821 if Present (Alias (E)) then
8822 Set_Overridden_Operation (S, Alias (E));
8826 if Is_Dispatching_Operation (E) then
8828 -- An overriding dispatching subprogram inherits the
8829 -- convention of the overridden subprogram (AI-117).
8831 Set_Convention (S, Convention (E));
8832 Check_Dispatching_Operation (S, E);
8835 Check_Dispatching_Operation (S, Empty);
8838 Check_For_Primitive_Subprogram
8839 (Is_Primitive_Subp, Is_Overriding => True);
8840 goto Check_Inequality;
8843 -- Apparent redeclarations in instances can occur when two
8844 -- formal types get the same actual type. The subprograms in
8845 -- in the instance are legal, even if not callable from the
8846 -- outside. Calls from within are disambiguated elsewhere.
8847 -- For dispatching operations in the visible part, the usual
8848 -- rules apply, and operations with the same profile are not
8851 elsif (In_Instance_Visible_Part
8852 and then not Is_Dispatching_Operation (E))
8853 or else In_Instance_Not_Visible
8857 -- Here we have a real error (identical profile)
8860 Error_Msg_Sloc := Sloc (E);
8862 -- Avoid cascaded errors if the entity appears in
8863 -- subsequent calls.
8865 Set_Scope (S, Current_Scope);
8867 -- Generate error, with extra useful warning for the case
8868 -- of a generic instance with no completion.
8870 if Is_Generic_Instance (S)
8871 and then not Has_Completion (E)
8874 ("instantiation cannot provide body for&", S);
8875 Error_Msg_N ("\& conflicts with declaration#", S);
8877 Error_Msg_N ("& conflicts with declaration#", S);
8884 -- If one subprogram has an access parameter and the other
8885 -- a parameter of an access type, calls to either might be
8886 -- ambiguous. Verify that parameters match except for the
8887 -- access parameter.
8889 if May_Hide_Profile then
8895 F1 := First_Formal (S);
8896 F2 := First_Formal (E);
8897 while Present (F1) and then Present (F2) loop
8898 if Is_Access_Type (Etype (F1)) then
8899 if not Is_Access_Type (Etype (F2))
8900 or else not Conforming_Types
8901 (Designated_Type (Etype (F1)),
8902 Designated_Type (Etype (F2)),
8905 May_Hide_Profile := False;
8909 not Conforming_Types
8910 (Etype (F1), Etype (F2), Type_Conformant)
8912 May_Hide_Profile := False;
8923 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
8932 -- On exit, we know that S is a new entity
8934 Enter_Overloaded_Entity (S);
8935 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8936 Check_Overriding_Indicator
8937 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8939 -- Overloading is not allowed in SPARK, except for operators
8941 if Nkind (S) /= N_Defining_Operator_Symbol then
8942 Error_Msg_Sloc := Sloc (Homonym (S));
8943 Check_SPARK_Restriction
8944 ("overloading not allowed with entity#", S);
8947 -- If S is a derived operation for an untagged type then by
8948 -- definition it's not a dispatching operation (even if the parent
8949 -- operation was dispatching), so Check_Dispatching_Operation is not
8950 -- called in that case.
8952 if No (Derived_Type)
8953 or else Is_Tagged_Type (Derived_Type)
8955 Check_Dispatching_Operation (S, Empty);
8959 -- If this is a user-defined equality operator that is not a derived
8960 -- subprogram, create the corresponding inequality. If the operation is
8961 -- dispatching, the expansion is done elsewhere, and we do not create
8962 -- an explicit inequality operation.
8964 <<Check_Inequality>>
8965 if Chars (S) = Name_Op_Eq
8966 and then Etype (S) = Standard_Boolean
8967 and then Present (Parent (S))
8968 and then not Is_Dispatching_Operation (S)
8970 Make_Inequality_Operator (S);
8972 if Ada_Version >= Ada_2012 then
8973 Check_Untagged_Equality (S);
8976 end New_Overloaded_Entity;
8978 ---------------------
8979 -- Process_Formals --
8980 ---------------------
8982 procedure Process_Formals
8984 Related_Nod : Node_Id)
8986 Param_Spec : Node_Id;
8988 Formal_Type : Entity_Id;
8992 Num_Out_Params : Nat := 0;
8993 First_Out_Param : Entity_Id := Empty;
8994 -- Used for setting Is_Only_Out_Parameter
8996 function Designates_From_With_Type (Typ : Entity_Id) return Boolean;
8997 -- Determine whether an access type designates a type coming from a
9000 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
9001 -- Check whether the default has a class-wide type. After analysis the
9002 -- default has the type of the formal, so we must also check explicitly
9003 -- for an access attribute.
9005 -------------------------------
9006 -- Designates_From_With_Type --
9007 -------------------------------
9009 function Designates_From_With_Type (Typ : Entity_Id) return Boolean is
9010 Desig : Entity_Id := Typ;
9013 if Is_Access_Type (Desig) then
9014 Desig := Directly_Designated_Type (Desig);
9017 if Is_Class_Wide_Type (Desig) then
9018 Desig := Root_Type (Desig);
9022 Ekind (Desig) = E_Incomplete_Type
9023 and then From_With_Type (Desig);
9024 end Designates_From_With_Type;
9026 ---------------------------
9027 -- Is_Class_Wide_Default --
9028 ---------------------------
9030 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
9032 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
9033 or else (Nkind (D) = N_Attribute_Reference
9034 and then Attribute_Name (D) = Name_Access
9035 and then Is_Class_Wide_Type (Etype (Prefix (D))));
9036 end Is_Class_Wide_Default;
9038 -- Start of processing for Process_Formals
9041 -- In order to prevent premature use of the formals in the same formal
9042 -- part, the Ekind is left undefined until all default expressions are
9043 -- analyzed. The Ekind is established in a separate loop at the end.
9045 Param_Spec := First (T);
9046 while Present (Param_Spec) loop
9047 Formal := Defining_Identifier (Param_Spec);
9048 Set_Never_Set_In_Source (Formal, True);
9049 Enter_Name (Formal);
9051 -- Case of ordinary parameters
9053 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
9054 Find_Type (Parameter_Type (Param_Spec));
9055 Ptype := Parameter_Type (Param_Spec);
9057 if Ptype = Error then
9061 Formal_Type := Entity (Ptype);
9063 if Is_Incomplete_Type (Formal_Type)
9065 (Is_Class_Wide_Type (Formal_Type)
9066 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
9068 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
9069 -- primitive operations, as long as their completion is
9070 -- in the same declarative part. If in the private part
9071 -- this means that the type cannot be a Taft-amendment type.
9072 -- Check is done on package exit. For access to subprograms,
9073 -- the use is legal for Taft-amendment types.
9075 if Is_Tagged_Type (Formal_Type) then
9076 if Ekind (Scope (Current_Scope)) = E_Package
9077 and then not From_With_Type (Formal_Type)
9078 and then not Is_Class_Wide_Type (Formal_Type)
9081 (Parent (T), N_Access_Function_Definition,
9082 N_Access_Procedure_Definition)
9086 Private_Dependents (Base_Type (Formal_Type)));
9088 -- Freezing is delayed to ensure that Register_Prim
9089 -- will get called for this operation, which is needed
9090 -- in cases where static dispatch tables aren't built.
9091 -- (Note that the same is done for controlling access
9092 -- parameter cases in function Access_Definition.)
9094 Set_Has_Delayed_Freeze (Current_Scope);
9098 -- Special handling of Value_Type for CIL case
9100 elsif Is_Value_Type (Formal_Type) then
9103 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
9104 N_Access_Procedure_Definition)
9106 -- AI05-0151: Tagged incomplete types are allowed in all
9107 -- formal parts. Untagged incomplete types are not allowed
9110 if Ada_Version >= Ada_2012 then
9111 if Is_Tagged_Type (Formal_Type) then
9114 elsif Nkind_In (Parent (Parent (T)), N_Accept_Statement,
9119 ("invalid use of untagged incomplete type&",
9120 Ptype, Formal_Type);
9125 ("invalid use of incomplete type&",
9126 Param_Spec, Formal_Type);
9128 -- Further checks on the legality of incomplete types
9129 -- in formal parts are delayed until the freeze point
9130 -- of the enclosing subprogram or access to subprogram.
9134 elsif Ekind (Formal_Type) = E_Void then
9136 ("premature use of&",
9137 Parameter_Type (Param_Spec), Formal_Type);
9140 -- Ada 2012 (AI-142): Handle aliased parameters
9142 if Ada_Version >= Ada_2012
9143 and then Aliased_Present (Param_Spec)
9145 Set_Is_Aliased (Formal);
9148 -- Ada 2005 (AI-231): Create and decorate an internal subtype
9149 -- declaration corresponding to the null-excluding type of the
9150 -- formal in the enclosing scope. Finally, replace the parameter
9151 -- type of the formal with the internal subtype.
9153 if Ada_Version >= Ada_2005
9154 and then Null_Exclusion_Present (Param_Spec)
9156 if not Is_Access_Type (Formal_Type) then
9158 ("`NOT NULL` allowed only for an access type", Param_Spec);
9161 if Can_Never_Be_Null (Formal_Type)
9162 and then Comes_From_Source (Related_Nod)
9165 ("`NOT NULL` not allowed (& already excludes null)",
9166 Param_Spec, Formal_Type);
9170 Create_Null_Excluding_Itype
9172 Related_Nod => Related_Nod,
9173 Scope_Id => Scope (Current_Scope));
9175 -- If the designated type of the itype is an itype we
9176 -- decorate it with the Has_Delayed_Freeze attribute to
9177 -- avoid problems with the backend.
9180 -- type T is access procedure;
9181 -- procedure Op (O : not null T);
9183 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
9184 Set_Has_Delayed_Freeze (Formal_Type);
9189 -- An access formal type
9193 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
9195 -- No need to continue if we already notified errors
9197 if not Present (Formal_Type) then
9201 -- Ada 2005 (AI-254)
9204 AD : constant Node_Id :=
9205 Access_To_Subprogram_Definition
9206 (Parameter_Type (Param_Spec));
9208 if Present (AD) and then Protected_Present (AD) then
9210 Replace_Anonymous_Access_To_Protected_Subprogram
9216 Set_Etype (Formal, Formal_Type);
9218 -- Deal with default expression if present
9220 Default := Expression (Param_Spec);
9222 if Present (Default) then
9223 Check_SPARK_Restriction
9224 ("default expression is not allowed", Default);
9226 if Out_Present (Param_Spec) then
9228 ("default initialization only allowed for IN parameters",
9232 -- Do the special preanalysis of the expression (see section on
9233 -- "Handling of Default Expressions" in the spec of package Sem).
9235 Preanalyze_Spec_Expression (Default, Formal_Type);
9237 -- An access to constant cannot be the default for
9238 -- an access parameter that is an access to variable.
9240 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9241 and then not Is_Access_Constant (Formal_Type)
9242 and then Is_Access_Type (Etype (Default))
9243 and then Is_Access_Constant (Etype (Default))
9246 ("formal that is access to variable cannot be initialized " &
9247 "with an access-to-constant expression", Default);
9250 -- Check that the designated type of an access parameter's default
9251 -- is not a class-wide type unless the parameter's designated type
9252 -- is also class-wide.
9254 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9255 and then not Designates_From_With_Type (Formal_Type)
9256 and then Is_Class_Wide_Default (Default)
9257 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
9260 ("access to class-wide expression not allowed here", Default);
9263 -- Check incorrect use of dynamically tagged expressions
9265 if Is_Tagged_Type (Formal_Type) then
9266 Check_Dynamically_Tagged_Expression
9269 Related_Nod => Default);
9273 -- Ada 2005 (AI-231): Static checks
9275 if Ada_Version >= Ada_2005
9276 and then Is_Access_Type (Etype (Formal))
9277 and then Can_Never_Be_Null (Etype (Formal))
9279 Null_Exclusion_Static_Checks (Param_Spec);
9286 -- If this is the formal part of a function specification, analyze the
9287 -- subtype mark in the context where the formals are visible but not
9288 -- yet usable, and may hide outer homographs.
9290 if Nkind (Related_Nod) = N_Function_Specification then
9291 Analyze_Return_Type (Related_Nod);
9294 -- Now set the kind (mode) of each formal
9296 Param_Spec := First (T);
9297 while Present (Param_Spec) loop
9298 Formal := Defining_Identifier (Param_Spec);
9299 Set_Formal_Mode (Formal);
9301 if Ekind (Formal) = E_In_Parameter then
9302 Set_Default_Value (Formal, Expression (Param_Spec));
9304 if Present (Expression (Param_Spec)) then
9305 Default := Expression (Param_Spec);
9307 if Is_Scalar_Type (Etype (Default)) then
9309 (Parameter_Type (Param_Spec)) /= N_Access_Definition
9311 Formal_Type := Entity (Parameter_Type (Param_Spec));
9314 Formal_Type := Access_Definition
9315 (Related_Nod, Parameter_Type (Param_Spec));
9318 Apply_Scalar_Range_Check (Default, Formal_Type);
9322 elsif Ekind (Formal) = E_Out_Parameter then
9323 Num_Out_Params := Num_Out_Params + 1;
9325 if Num_Out_Params = 1 then
9326 First_Out_Param := Formal;
9329 elsif Ekind (Formal) = E_In_Out_Parameter then
9330 Num_Out_Params := Num_Out_Params + 1;
9333 -- Force call by reference if aliased
9335 if Is_Aliased (Formal) then
9336 Set_Mechanism (Formal, By_Reference);
9342 if Present (First_Out_Param) and then Num_Out_Params = 1 then
9343 Set_Is_Only_Out_Parameter (First_Out_Param);
9345 end Process_Formals;
9351 procedure Process_PPCs
9353 Spec_Id : Entity_Id;
9354 Body_Id : Entity_Id)
9356 Loc : constant Source_Ptr := Sloc (N);
9360 Designator : Entity_Id;
9361 -- Subprogram designator, set from Spec_Id if present, else Body_Id
9363 Precond : Node_Id := Empty;
9364 -- Set non-Empty if we prepend precondition to the declarations. This
9365 -- is used to hook up inherited preconditions (adding the condition
9366 -- expression with OR ELSE, and adding the message).
9368 Inherited_Precond : Node_Id;
9369 -- Precondition inherited from parent subprogram
9371 Inherited : constant Subprogram_List :=
9372 Inherited_Subprograms (Spec_Id);
9373 -- List of subprograms inherited by this subprogram
9375 Plist : List_Id := No_List;
9376 -- List of generated postconditions
9378 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id;
9379 -- Prag contains an analyzed precondition or postcondition pragma. This
9380 -- function copies the pragma, changes it to the corresponding Check
9381 -- pragma and returns the Check pragma as the result. If Pspec is non-
9382 -- empty, this is the case of inheriting a PPC, where we must change
9383 -- references to parameters of the inherited subprogram to point to the
9384 -- corresponding parameters of the current subprogram.
9386 function Invariants_Or_Predicates_Present return Boolean;
9387 -- Determines if any invariants or predicates are present for any OUT
9388 -- or IN OUT parameters of the subprogram, or (for a function) if the
9389 -- return value has an invariant.
9395 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id is
9396 Nam : constant Name_Id := Pragma_Name (Prag);
9401 -- Prepare map if this is the case where we have to map entities of
9402 -- arguments in the overridden subprogram to corresponding entities
9403 -- of the current subprogram.
9414 Map := New_Elmt_List;
9415 PF := First_Formal (Pspec);
9416 CF := First_Formal (Designator);
9417 while Present (PF) loop
9418 Append_Elmt (PF, Map);
9419 Append_Elmt (CF, Map);
9426 -- Now we can copy the tree, doing any required substitutions
9428 CP := New_Copy_Tree (Prag, Map => Map, New_Scope => Current_Scope);
9430 -- Set Analyzed to false, since we want to reanalyze the check
9431 -- procedure. Note that it is only at the outer level that we
9432 -- do this fiddling, for the spec cases, the already preanalyzed
9433 -- parameters are not affected.
9435 Set_Analyzed (CP, False);
9437 -- We also make sure Comes_From_Source is False for the copy
9439 Set_Comes_From_Source (CP, False);
9441 -- For a postcondition pragma within a generic, preserve the pragma
9442 -- for later expansion.
9444 if Nam = Name_Postcondition
9445 and then not Expander_Active
9450 -- Change copy of pragma into corresponding pragma Check
9452 Prepend_To (Pragma_Argument_Associations (CP),
9453 Make_Pragma_Argument_Association (Sloc (Prag),
9454 Expression => Make_Identifier (Loc, Nam)));
9455 Set_Pragma_Identifier (CP, Make_Identifier (Sloc (Prag), Name_Check));
9457 -- If this is inherited case and the current message starts with
9458 -- "failed p", we change it to "failed inherited p...".
9460 if Present (Pspec) then
9462 Msg : constant Node_Id :=
9463 Last (Pragma_Argument_Associations (CP));
9466 if Chars (Msg) = Name_Message then
9467 String_To_Name_Buffer (Strval (Expression (Msg)));
9469 if Name_Buffer (1 .. 8) = "failed p" then
9470 Insert_Str_In_Name_Buffer ("inherited ", 8);
9472 (Expression (Last (Pragma_Argument_Associations (CP))),
9473 String_From_Name_Buffer);
9479 -- Return the check pragma
9484 --------------------------------------
9485 -- Invariants_Or_Predicates_Present --
9486 --------------------------------------
9488 function Invariants_Or_Predicates_Present return Boolean is
9492 -- Check function return result
9494 if Ekind (Designator) /= E_Procedure
9495 and then Has_Invariants (Etype (Designator))
9502 Formal := First_Formal (Designator);
9503 while Present (Formal) loop
9504 if Ekind (Formal) /= E_In_Parameter
9506 (Has_Invariants (Etype (Formal))
9507 or else Present (Predicate_Function (Etype (Formal))))
9512 Next_Formal (Formal);
9516 end Invariants_Or_Predicates_Present;
9518 -- Start of processing for Process_PPCs
9521 -- Capture designator from spec if present, else from body
9523 if Present (Spec_Id) then
9524 Designator := Spec_Id;
9526 Designator := Body_Id;
9529 -- Grab preconditions from spec
9531 if Present (Spec_Id) then
9533 -- Loop through PPC pragmas from spec. Note that preconditions from
9534 -- the body will be analyzed and converted when we scan the body
9535 -- declarations below.
9537 Prag := Spec_PPC_List (Contract (Spec_Id));
9538 while Present (Prag) loop
9539 if Pragma_Name (Prag) = Name_Precondition then
9541 -- For Pre (or Precondition pragma), we simply prepend the
9542 -- pragma to the list of declarations right away so that it
9543 -- will be executed at the start of the procedure. Note that
9544 -- this processing reverses the order of the list, which is
9545 -- what we want since new entries were chained to the head of
9546 -- the list. There can be more than one precondition when we
9547 -- use pragma Precondition.
9549 if not Class_Present (Prag) then
9550 Prepend (Grab_PPC, Declarations (N));
9552 -- For Pre'Class there can only be one pragma, and we save
9553 -- it in Precond for now. We will add inherited Pre'Class
9554 -- stuff before inserting this pragma in the declarations.
9556 Precond := Grab_PPC;
9560 Prag := Next_Pragma (Prag);
9563 -- Now deal with inherited preconditions
9565 for J in Inherited'Range loop
9566 Prag := Spec_PPC_List (Contract (Inherited (J)));
9568 while Present (Prag) loop
9569 if Pragma_Name (Prag) = Name_Precondition
9570 and then Class_Present (Prag)
9572 Inherited_Precond := Grab_PPC (Inherited (J));
9574 -- No precondition so far, so establish this as the first
9576 if No (Precond) then
9577 Precond := Inherited_Precond;
9579 -- Here we already have a precondition, add inherited one
9582 -- Add new precondition to old one using OR ELSE
9585 New_Expr : constant Node_Id :=
9589 (Pragma_Argument_Associations
9590 (Inherited_Precond))));
9591 Old_Expr : constant Node_Id :=
9595 (Pragma_Argument_Associations
9599 if Paren_Count (Old_Expr) = 0 then
9600 Set_Paren_Count (Old_Expr, 1);
9603 if Paren_Count (New_Expr) = 0 then
9604 Set_Paren_Count (New_Expr, 1);
9608 Make_Or_Else (Sloc (Old_Expr),
9609 Left_Opnd => Relocate_Node (Old_Expr),
9610 Right_Opnd => New_Expr));
9613 -- Add new message in the form:
9615 -- failed precondition from bla
9616 -- also failed inherited precondition from bla
9619 -- Skip this if exception locations are suppressed
9621 if not Exception_Locations_Suppressed then
9623 New_Msg : constant Node_Id :=
9626 (Pragma_Argument_Associations
9627 (Inherited_Precond)));
9628 Old_Msg : constant Node_Id :=
9631 (Pragma_Argument_Associations
9634 Start_String (Strval (Old_Msg));
9635 Store_String_Chars (ASCII.LF & " also ");
9636 Store_String_Chars (Strval (New_Msg));
9637 Set_Strval (Old_Msg, End_String);
9643 Prag := Next_Pragma (Prag);
9647 -- If we have built a precondition for Pre'Class (including any
9648 -- Pre'Class aspects inherited from parent subprograms), then we
9649 -- insert this composite precondition at this stage.
9651 if Present (Precond) then
9652 Prepend (Precond, Declarations (N));
9656 -- Build postconditions procedure if needed and prepend the following
9657 -- declaration to the start of the declarations for the subprogram.
9659 -- procedure _postconditions [(_Result : resulttype)] is
9661 -- pragma Check (Postcondition, condition [,message]);
9662 -- pragma Check (Postcondition, condition [,message]);
9664 -- Invariant_Procedure (_Result) ...
9665 -- Invariant_Procedure (Arg1)
9669 -- First we deal with the postconditions in the body
9671 if Is_Non_Empty_List (Declarations (N)) then
9673 -- Loop through declarations
9675 Prag := First (Declarations (N));
9676 while Present (Prag) loop
9677 if Nkind (Prag) = N_Pragma then
9679 -- If pragma, capture if enabled postcondition, else ignore
9681 if Pragma_Name (Prag) = Name_Postcondition
9682 and then Check_Enabled (Name_Postcondition)
9684 if Plist = No_List then
9685 Plist := Empty_List;
9690 -- If expansion is disabled, as in a generic unit, save
9691 -- pragma for later expansion.
9693 if not Expander_Active then
9694 Prepend (Grab_PPC, Declarations (N));
9696 Append (Grab_PPC, Plist);
9702 -- Not a pragma, if comes from source, then end scan
9704 elsif Comes_From_Source (Prag) then
9707 -- Skip stuff not coming from source
9715 -- Now deal with any postconditions from the spec
9717 if Present (Spec_Id) then
9718 Spec_Postconditions : declare
9719 procedure Process_Post_Conditions
9722 -- This processes the Spec_PPC_List from Spec, processing any
9723 -- postconditions from the list. If Class is True, then only
9724 -- postconditions marked with Class_Present are considered.
9725 -- The caller has checked that Spec_PPC_List is non-Empty.
9727 -----------------------------
9728 -- Process_Post_Conditions --
9729 -----------------------------
9731 procedure Process_Post_Conditions
9744 -- Loop through PPC pragmas from spec
9746 Prag := Spec_PPC_List (Contract (Spec));
9748 if Pragma_Name (Prag) = Name_Postcondition
9749 and then (not Class or else Class_Present (Prag))
9751 if Plist = No_List then
9752 Plist := Empty_List;
9755 if not Expander_Active then
9757 (Grab_PPC (Pspec), Declarations (N));
9759 Append (Grab_PPC (Pspec), Plist);
9763 Prag := Next_Pragma (Prag);
9764 exit when No (Prag);
9766 end Process_Post_Conditions;
9768 -- Start of processing for Spec_Postconditions
9771 if Present (Spec_PPC_List (Contract (Spec_Id))) then
9772 Process_Post_Conditions (Spec_Id, Class => False);
9775 -- Process inherited postconditions
9777 for J in Inherited'Range loop
9778 if Present (Spec_PPC_List (Contract (Inherited (J)))) then
9779 Process_Post_Conditions (Inherited (J), Class => True);
9782 end Spec_Postconditions;
9785 -- If we had any postconditions and expansion is enabled, or if the
9786 -- procedure has invariants, then build the _Postconditions procedure.
9788 if (Present (Plist) or else Invariants_Or_Predicates_Present)
9789 and then Expander_Active
9792 Plist := Empty_List;
9795 -- Special processing for function case
9797 if Ekind (Designator) /= E_Procedure then
9799 Rent : constant Entity_Id :=
9800 Make_Defining_Identifier (Loc, Name_uResult);
9801 Ftyp : constant Entity_Id := Etype (Designator);
9804 Set_Etype (Rent, Ftyp);
9806 -- Add argument for return
9810 Make_Parameter_Specification (Loc,
9811 Parameter_Type => New_Occurrence_Of (Ftyp, Loc),
9812 Defining_Identifier => Rent));
9814 -- Add invariant call if returning type with invariants
9816 if Has_Invariants (Etype (Rent))
9817 and then Present (Invariant_Procedure (Etype (Rent)))
9820 Make_Invariant_Call (New_Occurrence_Of (Rent, Loc)));
9824 -- Procedure rather than a function
9830 -- Add invariant calls and predicate calls for parameters. Note that
9831 -- this is done for functions as well, since in Ada 2012 they can
9832 -- have IN OUT args.
9839 Formal := First_Formal (Designator);
9840 while Present (Formal) loop
9841 if Ekind (Formal) /= E_In_Parameter then
9842 Ftype := Etype (Formal);
9844 if Has_Invariants (Ftype)
9845 and then Present (Invariant_Procedure (Ftype))
9849 (New_Occurrence_Of (Formal, Loc)));
9852 if Present (Predicate_Function (Ftype)) then
9854 Make_Predicate_Check
9855 (Ftype, New_Occurrence_Of (Formal, Loc)));
9859 Next_Formal (Formal);
9863 -- Build and insert postcondition procedure
9866 Post_Proc : constant Entity_Id :=
9867 Make_Defining_Identifier (Loc,
9868 Chars => Name_uPostconditions);
9869 -- The entity for the _Postconditions procedure
9872 Prepend_To (Declarations (N),
9873 Make_Subprogram_Body (Loc,
9875 Make_Procedure_Specification (Loc,
9876 Defining_Unit_Name => Post_Proc,
9877 Parameter_Specifications => Parms),
9879 Declarations => Empty_List,
9881 Handled_Statement_Sequence =>
9882 Make_Handled_Sequence_Of_Statements (Loc,
9883 Statements => Plist)));
9885 Set_Ekind (Post_Proc, E_Procedure);
9887 -- If this is a procedure, set the Postcondition_Proc attribute on
9888 -- the proper defining entity for the subprogram.
9890 if Ekind (Designator) = E_Procedure then
9891 Set_Postcondition_Proc (Designator, Post_Proc);
9895 Set_Has_Postconditions (Designator);
9899 ----------------------------
9900 -- Reference_Body_Formals --
9901 ----------------------------
9903 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
9908 if Error_Posted (Spec) then
9912 -- Iterate over both lists. They may be of different lengths if the two
9913 -- specs are not conformant.
9915 Fs := First_Formal (Spec);
9916 Fb := First_Formal (Bod);
9917 while Present (Fs) and then Present (Fb) loop
9918 Generate_Reference (Fs, Fb, 'b');
9921 Style.Check_Identifier (Fb, Fs);
9924 Set_Spec_Entity (Fb, Fs);
9925 Set_Referenced (Fs, False);
9929 end Reference_Body_Formals;
9931 -------------------------
9932 -- Set_Actual_Subtypes --
9933 -------------------------
9935 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
9939 First_Stmt : Node_Id := Empty;
9940 AS_Needed : Boolean;
9943 -- If this is an empty initialization procedure, no need to create
9944 -- actual subtypes (small optimization).
9946 if Ekind (Subp) = E_Procedure
9947 and then Is_Null_Init_Proc (Subp)
9952 Formal := First_Formal (Subp);
9953 while Present (Formal) loop
9954 T := Etype (Formal);
9956 -- We never need an actual subtype for a constrained formal
9958 if Is_Constrained (T) then
9961 -- If we have unknown discriminants, then we do not need an actual
9962 -- subtype, or more accurately we cannot figure it out! Note that
9963 -- all class-wide types have unknown discriminants.
9965 elsif Has_Unknown_Discriminants (T) then
9968 -- At this stage we have an unconstrained type that may need an
9969 -- actual subtype. For sure the actual subtype is needed if we have
9970 -- an unconstrained array type.
9972 elsif Is_Array_Type (T) then
9975 -- The only other case needing an actual subtype is an unconstrained
9976 -- record type which is an IN parameter (we cannot generate actual
9977 -- subtypes for the OUT or IN OUT case, since an assignment can
9978 -- change the discriminant values. However we exclude the case of
9979 -- initialization procedures, since discriminants are handled very
9980 -- specially in this context, see the section entitled "Handling of
9981 -- Discriminants" in Einfo.
9983 -- We also exclude the case of Discrim_SO_Functions (functions used
9984 -- in front end layout mode for size/offset values), since in such
9985 -- functions only discriminants are referenced, and not only are such
9986 -- subtypes not needed, but they cannot always be generated, because
9987 -- of order of elaboration issues.
9989 elsif Is_Record_Type (T)
9990 and then Ekind (Formal) = E_In_Parameter
9991 and then Chars (Formal) /= Name_uInit
9992 and then not Is_Unchecked_Union (T)
9993 and then not Is_Discrim_SO_Function (Subp)
9997 -- All other cases do not need an actual subtype
10000 AS_Needed := False;
10003 -- Generate actual subtypes for unconstrained arrays and
10004 -- unconstrained discriminated records.
10007 if Nkind (N) = N_Accept_Statement then
10009 -- If expansion is active, the formal is replaced by a local
10010 -- variable that renames the corresponding entry of the
10011 -- parameter block, and it is this local variable that may
10012 -- require an actual subtype.
10014 if Full_Expander_Active then
10015 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
10017 Decl := Build_Actual_Subtype (T, Formal);
10020 if Present (Handled_Statement_Sequence (N)) then
10022 First (Statements (Handled_Statement_Sequence (N)));
10023 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
10024 Mark_Rewrite_Insertion (Decl);
10026 -- If the accept statement has no body, there will be no
10027 -- reference to the actuals, so no need to compute actual
10034 Decl := Build_Actual_Subtype (T, Formal);
10035 Prepend (Decl, Declarations (N));
10036 Mark_Rewrite_Insertion (Decl);
10039 -- The declaration uses the bounds of an existing object, and
10040 -- therefore needs no constraint checks.
10042 Analyze (Decl, Suppress => All_Checks);
10044 -- We need to freeze manually the generated type when it is
10045 -- inserted anywhere else than in a declarative part.
10047 if Present (First_Stmt) then
10048 Insert_List_Before_And_Analyze (First_Stmt,
10049 Freeze_Entity (Defining_Identifier (Decl), N));
10052 if Nkind (N) = N_Accept_Statement
10053 and then Full_Expander_Active
10055 Set_Actual_Subtype (Renamed_Object (Formal),
10056 Defining_Identifier (Decl));
10058 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
10062 Next_Formal (Formal);
10064 end Set_Actual_Subtypes;
10066 ---------------------
10067 -- Set_Formal_Mode --
10068 ---------------------
10070 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
10071 Spec : constant Node_Id := Parent (Formal_Id);
10074 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
10075 -- since we ensure that corresponding actuals are always valid at the
10076 -- point of the call.
10078 if Out_Present (Spec) then
10079 if Ekind (Scope (Formal_Id)) = E_Function
10080 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
10082 -- [IN] OUT parameters allowed for functions in Ada 2012
10084 if Ada_Version >= Ada_2012 then
10085 if In_Present (Spec) then
10086 Set_Ekind (Formal_Id, E_In_Out_Parameter);
10088 Set_Ekind (Formal_Id, E_Out_Parameter);
10091 -- But not in earlier versions of Ada
10094 Error_Msg_N ("functions can only have IN parameters", Spec);
10095 Set_Ekind (Formal_Id, E_In_Parameter);
10098 elsif In_Present (Spec) then
10099 Set_Ekind (Formal_Id, E_In_Out_Parameter);
10102 Set_Ekind (Formal_Id, E_Out_Parameter);
10103 Set_Never_Set_In_Source (Formal_Id, True);
10104 Set_Is_True_Constant (Formal_Id, False);
10105 Set_Current_Value (Formal_Id, Empty);
10109 Set_Ekind (Formal_Id, E_In_Parameter);
10112 -- Set Is_Known_Non_Null for access parameters since the language
10113 -- guarantees that access parameters are always non-null. We also set
10114 -- Can_Never_Be_Null, since there is no way to change the value.
10116 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
10118 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
10119 -- null; In Ada 2005, only if then null_exclusion is explicit.
10121 if Ada_Version < Ada_2005
10122 or else Can_Never_Be_Null (Etype (Formal_Id))
10124 Set_Is_Known_Non_Null (Formal_Id);
10125 Set_Can_Never_Be_Null (Formal_Id);
10128 -- Ada 2005 (AI-231): Null-exclusion access subtype
10130 elsif Is_Access_Type (Etype (Formal_Id))
10131 and then Can_Never_Be_Null (Etype (Formal_Id))
10133 Set_Is_Known_Non_Null (Formal_Id);
10136 Set_Mechanism (Formal_Id, Default_Mechanism);
10137 Set_Formal_Validity (Formal_Id);
10138 end Set_Formal_Mode;
10140 -------------------------
10141 -- Set_Formal_Validity --
10142 -------------------------
10144 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
10146 -- If no validity checking, then we cannot assume anything about the
10147 -- validity of parameters, since we do not know there is any checking
10148 -- of the validity on the call side.
10150 if not Validity_Checks_On then
10153 -- If validity checking for parameters is enabled, this means we are
10154 -- not supposed to make any assumptions about argument values.
10156 elsif Validity_Check_Parameters then
10159 -- If we are checking in parameters, we will assume that the caller is
10160 -- also checking parameters, so we can assume the parameter is valid.
10162 elsif Ekind (Formal_Id) = E_In_Parameter
10163 and then Validity_Check_In_Params
10165 Set_Is_Known_Valid (Formal_Id, True);
10167 -- Similar treatment for IN OUT parameters
10169 elsif Ekind (Formal_Id) = E_In_Out_Parameter
10170 and then Validity_Check_In_Out_Params
10172 Set_Is_Known_Valid (Formal_Id, True);
10174 end Set_Formal_Validity;
10176 ------------------------
10177 -- Subtype_Conformant --
10178 ------------------------
10180 function Subtype_Conformant
10181 (New_Id : Entity_Id;
10182 Old_Id : Entity_Id;
10183 Skip_Controlling_Formals : Boolean := False) return Boolean
10187 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
10188 Skip_Controlling_Formals => Skip_Controlling_Formals);
10190 end Subtype_Conformant;
10192 ---------------------
10193 -- Type_Conformant --
10194 ---------------------
10196 function Type_Conformant
10197 (New_Id : Entity_Id;
10198 Old_Id : Entity_Id;
10199 Skip_Controlling_Formals : Boolean := False) return Boolean
10203 May_Hide_Profile := False;
10206 (New_Id, Old_Id, Type_Conformant, False, Result,
10207 Skip_Controlling_Formals => Skip_Controlling_Formals);
10209 end Type_Conformant;
10211 -------------------------------
10212 -- Valid_Operator_Definition --
10213 -------------------------------
10215 procedure Valid_Operator_Definition (Designator : Entity_Id) is
10218 Id : constant Name_Id := Chars (Designator);
10222 F := First_Formal (Designator);
10223 while Present (F) loop
10226 if Present (Default_Value (F)) then
10228 ("default values not allowed for operator parameters",
10235 -- Verify that user-defined operators have proper number of arguments
10236 -- First case of operators which can only be unary
10238 if Id = Name_Op_Not
10239 or else Id = Name_Op_Abs
10243 -- Case of operators which can be unary or binary
10245 elsif Id = Name_Op_Add
10246 or Id = Name_Op_Subtract
10248 N_OK := (N in 1 .. 2);
10250 -- All other operators can only be binary
10258 ("incorrect number of arguments for operator", Designator);
10262 and then Base_Type (Etype (Designator)) = Standard_Boolean
10263 and then not Is_Intrinsic_Subprogram (Designator)
10266 ("explicit definition of inequality not allowed", Designator);
10268 end Valid_Operator_Definition;
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