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 function Is_Non_Overriding_Operation
186 New_E : Entity_Id) return Boolean;
187 -- Enforce the rule given in 12.3(18): a private operation in an instance
188 -- overrides an inherited operation only if the corresponding operation
189 -- was overriding in the generic. This can happen for primitive operations
190 -- of types derived (in the generic unit) from formal private or formal
193 procedure Make_Inequality_Operator (S : Entity_Id);
194 -- Create the declaration for an inequality operator that is implicitly
195 -- created by a user-defined equality operator that yields a boolean.
197 procedure May_Need_Actuals (Fun : Entity_Id);
198 -- Flag functions that can be called without parameters, i.e. those that
199 -- have no parameters, or those for which defaults exist for all parameters
201 procedure Process_PPCs
204 Body_Id : Entity_Id);
205 -- Called from Analyze[_Generic]_Subprogram_Body to deal with scanning post
206 -- conditions for the body and assembling and inserting the _postconditions
207 -- procedure. N is the node for the subprogram body and Body_Id/Spec_Id are
208 -- the entities for the body and separate spec (if there is no separate
209 -- spec, Spec_Id is Empty). Note that invariants and predicates may also
210 -- provide postconditions, and are also handled in this procedure.
212 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
213 -- Formal_Id is an formal parameter entity. This procedure deals with
214 -- setting the proper validity status for this entity, which depends on
215 -- the kind of parameter and the validity checking mode.
217 ---------------------------------------------
218 -- Analyze_Abstract_Subprogram_Declaration --
219 ---------------------------------------------
221 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
222 Designator : constant Entity_Id :=
223 Analyze_Subprogram_Specification (Specification (N));
224 Scop : constant Entity_Id := Current_Scope;
227 Check_SPARK_Restriction ("abstract subprogram is not allowed", N);
229 Generate_Definition (Designator);
230 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
231 Set_Is_Abstract_Subprogram (Designator);
232 New_Overloaded_Entity (Designator);
233 Check_Delayed_Subprogram (Designator);
235 Set_Categorization_From_Scope (Designator, Scop);
237 if Ekind (Scope (Designator)) = E_Protected_Type then
239 ("abstract subprogram not allowed in protected type", N);
241 -- Issue a warning if the abstract subprogram is neither a dispatching
242 -- operation nor an operation that overrides an inherited subprogram or
243 -- predefined operator, since this most likely indicates a mistake.
245 elsif Warn_On_Redundant_Constructs
246 and then not Is_Dispatching_Operation (Designator)
247 and then not Present (Overridden_Operation (Designator))
248 and then (not Is_Operator_Symbol_Name (Chars (Designator))
249 or else Scop /= Scope (Etype (First_Formal (Designator))))
252 ("?abstract subprogram is not dispatching or overriding", N);
255 Generate_Reference_To_Formals (Designator);
256 Check_Eliminated (Designator);
258 if Has_Aspects (N) then
259 Analyze_Aspect_Specifications (N, Designator);
261 end Analyze_Abstract_Subprogram_Declaration;
263 ---------------------------------
264 -- Analyze_Expression_Function --
265 ---------------------------------
267 procedure Analyze_Expression_Function (N : Node_Id) is
268 Loc : constant Source_Ptr := Sloc (N);
269 LocX : constant Source_Ptr := Sloc (Expression (N));
270 Def_Id : constant Entity_Id := Defining_Entity (Specification (N));
271 Expr : constant Node_Id := Expression (N);
275 Prev : constant Entity_Id := Current_Entity_In_Scope (Def_Id);
276 -- If the expression is a completion, Prev is the entity whose
277 -- declaration is completed.
280 -- This is one of the occasions on which we transform the tree during
281 -- semantic analysis. If this is a completion, transform the expression
282 -- function into an equivalent subprogram body, and analyze it.
284 -- Expression functions are inlined unconditionally. The back-end will
285 -- determine whether this is possible.
287 Inline_Processing_Required := True;
290 Make_Subprogram_Body (Loc,
291 Specification => Copy_Separate_Tree (Specification (N)),
292 Declarations => Empty_List,
293 Handled_Statement_Sequence =>
294 Make_Handled_Sequence_Of_Statements (LocX,
295 Statements => New_List (
296 Make_Simple_Return_Statement (LocX,
297 Expression => Expression (N)))));
299 if Present (Prev) and then Ekind (Prev) = E_Generic_Function then
301 -- If the expression completes a generic subprogram, we must create a
302 -- separate node for the body, because at instantiation the original
303 -- node of the generic copy must be a generic subprogram body, and
304 -- cannot be a expression function. Otherwise we just rewrite the
305 -- expression with the non-generic body.
307 Insert_After (N, New_Body);
308 Rewrite (N, Make_Null_Statement (Loc));
311 Set_Is_Inlined (Prev);
314 and then Comes_From_Source (Prev)
316 Rewrite (N, New_Body);
319 -- Prev is the previous entity with the same name, but it is can
320 -- be an unrelated spec that is not completed by the expression
321 -- function. In that case the relevant entity is the one in the body.
322 -- Not clear that the backend can inline it in this case ???
324 if Has_Completion (Prev) then
325 Set_Is_Inlined (Prev);
327 Set_Is_Inlined (Defining_Entity (New_Body));
330 -- If this is not a completion, create both a declaration and a body, so
331 -- that the expression can be inlined whenever possible.
335 Make_Subprogram_Declaration (Loc,
336 Specification => Specification (N));
338 Rewrite (N, New_Decl);
340 Set_Is_Inlined (Defining_Entity (New_Decl));
342 -- To prevent premature freeze action, insert the new body at the end
343 -- of the current declarations, or at the end of the package spec.
346 Decls : List_Id := List_Containing (N);
347 Par : constant Node_Id := Parent (Decls);
350 if Nkind (Par) = N_Package_Specification
351 and then Decls = Visible_Declarations (Par)
352 and then Present (Private_Declarations (Par))
353 and then not Is_Empty_List (Private_Declarations (Par))
355 Decls := Private_Declarations (Par);
358 Insert_After (Last (Decls), New_Body);
362 -- If the return expression is a static constant, we suppress warning
363 -- messages on unused formals, which in most cases will be noise.
365 Set_Is_Trivial_Subprogram (Defining_Entity (New_Body),
366 Is_OK_Static_Expression (Expr));
367 end Analyze_Expression_Function;
369 ----------------------------------------
370 -- Analyze_Extended_Return_Statement --
371 ----------------------------------------
373 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
375 Analyze_Return_Statement (N);
376 end Analyze_Extended_Return_Statement;
378 ----------------------------
379 -- Analyze_Function_Call --
380 ----------------------------
382 procedure Analyze_Function_Call (N : Node_Id) is
383 P : constant Node_Id := Name (N);
384 Actuals : constant List_Id := Parameter_Associations (N);
390 -- A call of the form A.B (X) may be an Ada 05 call, which is rewritten
391 -- as B (A, X). If the rewriting is successful, the call has been
392 -- analyzed and we just return.
394 if Nkind (P) = N_Selected_Component
395 and then Name (N) /= P
396 and then Is_Rewrite_Substitution (N)
397 and then Present (Etype (N))
402 -- If error analyzing name, then set Any_Type as result type and return
404 if Etype (P) = Any_Type then
405 Set_Etype (N, Any_Type);
409 -- Otherwise analyze the parameters
411 if Present (Actuals) then
412 Actual := First (Actuals);
413 while Present (Actual) loop
415 Check_Parameterless_Call (Actual);
421 end Analyze_Function_Call;
423 -----------------------------
424 -- Analyze_Function_Return --
425 -----------------------------
427 procedure Analyze_Function_Return (N : Node_Id) is
428 Loc : constant Source_Ptr := Sloc (N);
429 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
430 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
432 R_Type : constant Entity_Id := Etype (Scope_Id);
433 -- Function result subtype
435 procedure Check_Limited_Return (Expr : Node_Id);
436 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
437 -- limited types. Used only for simple return statements.
438 -- Expr is the expression returned.
440 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
441 -- Check that the return_subtype_indication properly matches the result
442 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
444 --------------------------
445 -- Check_Limited_Return --
446 --------------------------
448 procedure Check_Limited_Return (Expr : Node_Id) is
450 -- Ada 2005 (AI-318-02): Return-by-reference types have been
451 -- removed and replaced by anonymous access results. This is an
452 -- incompatibility with Ada 95. Not clear whether this should be
453 -- enforced yet or perhaps controllable with special switch. ???
455 -- A limited interface that is not immutably limited is OK.
457 if Is_Limited_Interface (R_Type)
459 not (Is_Task_Interface (R_Type)
460 or else Is_Protected_Interface (R_Type)
461 or else Is_Synchronized_Interface (R_Type))
465 elsif Is_Limited_Type (R_Type)
466 and then not Is_Interface (R_Type)
467 and then Comes_From_Source (N)
468 and then not In_Instance_Body
469 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
473 if Ada_Version >= Ada_2005
474 and then not Debug_Flag_Dot_L
475 and then not GNAT_Mode
478 ("(Ada 2005) cannot copy object of a limited type " &
479 "(RM-2005 6.5(5.5/2))", Expr);
481 if Is_Immutably_Limited_Type (R_Type) then
483 ("\return by reference not permitted in Ada 2005", Expr);
486 -- Warn in Ada 95 mode, to give folks a heads up about this
489 -- In GNAT mode, this is just a warning, to allow it to be
490 -- evilly turned off. Otherwise it is a real error.
492 -- In a generic context, simplify the warning because it makes
493 -- no sense to discuss pass-by-reference or copy.
495 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
496 if Inside_A_Generic then
498 ("return of limited object not permitted in Ada 2005 "
499 & "(RM-2005 6.5(5.5/2))?", Expr);
501 elsif Is_Immutably_Limited_Type (R_Type) then
503 ("return by reference not permitted in Ada 2005 "
504 & "(RM-2005 6.5(5.5/2))?", Expr);
507 ("cannot copy object of a limited type in Ada 2005 "
508 & "(RM-2005 6.5(5.5/2))?", Expr);
511 -- Ada 95 mode, compatibility warnings disabled
514 return; -- skip continuation messages below
517 if not Inside_A_Generic then
519 ("\consider switching to return of access type", Expr);
520 Explain_Limited_Type (R_Type, Expr);
523 end Check_Limited_Return;
525 -------------------------------------
526 -- Check_Return_Subtype_Indication --
527 -------------------------------------
529 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
530 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
532 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
533 -- Subtype given in the extended return statement (must match R_Type)
535 Subtype_Ind : constant Node_Id :=
536 Object_Definition (Original_Node (Obj_Decl));
538 R_Type_Is_Anon_Access :
540 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
542 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
544 Ekind (R_Type) = E_Anonymous_Access_Type;
545 -- True if return type of the function is an anonymous access type
546 -- Can't we make Is_Anonymous_Access_Type in einfo ???
548 R_Stm_Type_Is_Anon_Access :
550 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
552 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
554 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
555 -- True if type of the return object is an anonymous access type
558 -- First, avoid cascaded errors
560 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
564 -- "return access T" case; check that the return statement also has
565 -- "access T", and that the subtypes statically match:
566 -- if this is an access to subprogram the signatures must match.
568 if R_Type_Is_Anon_Access then
569 if R_Stm_Type_Is_Anon_Access then
571 Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
573 if Base_Type (Designated_Type (R_Stm_Type)) /=
574 Base_Type (Designated_Type (R_Type))
575 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
578 ("subtype must statically match function result subtype",
579 Subtype_Mark (Subtype_Ind));
583 -- For two anonymous access to subprogram types, the
584 -- types themselves must be type conformant.
586 if not Conforming_Types
587 (R_Stm_Type, R_Type, Fully_Conformant)
590 ("subtype must statically match function result subtype",
596 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
599 -- If the return object is of an anonymous access type, then report
600 -- an error if the function's result type is not also anonymous.
602 elsif R_Stm_Type_Is_Anon_Access
603 and then not R_Type_Is_Anon_Access
605 Error_Msg_N ("anonymous access not allowed for function with " &
606 "named access result", Subtype_Ind);
608 -- Subtype indication case: check that the return object's type is
609 -- covered by the result type, and that the subtypes statically match
610 -- when the result subtype is constrained. Also handle record types
611 -- with unknown discriminants for which we have built the underlying
612 -- record view. Coverage is needed to allow specific-type return
613 -- objects when the result type is class-wide (see AI05-32).
615 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
616 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
620 Underlying_Record_View (Base_Type (R_Stm_Type))))
622 -- A null exclusion may be present on the return type, on the
623 -- function specification, on the object declaration or on the
626 if Is_Access_Type (R_Type)
628 (Can_Never_Be_Null (R_Type)
629 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
630 Can_Never_Be_Null (R_Stm_Type)
633 ("subtype must statically match function result subtype",
637 -- AI05-103: for elementary types, subtypes must statically match
639 if Is_Constrained (R_Type)
640 or else Is_Access_Type (R_Type)
642 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
644 ("subtype must statically match function result subtype",
649 elsif Etype (Base_Type (R_Type)) = R_Stm_Type
650 and then Is_Null_Extension (Base_Type (R_Type))
656 ("wrong type for return_subtype_indication", Subtype_Ind);
658 end Check_Return_Subtype_Indication;
660 ---------------------
661 -- Local Variables --
662 ---------------------
666 -- Start of processing for Analyze_Function_Return
669 Set_Return_Present (Scope_Id);
671 if Nkind (N) = N_Simple_Return_Statement then
672 Expr := Expression (N);
674 -- Guard against a malformed expression. The parser may have tried to
675 -- recover but the node is not analyzable.
677 if Nkind (Expr) = N_Error then
678 Set_Etype (Expr, Any_Type);
679 Expander_Mode_Save_And_Set (False);
683 -- The resolution of a controlled [extension] aggregate associated
684 -- with a return statement creates a temporary which needs to be
685 -- finalized on function exit. Wrap the return statement inside a
686 -- block so that the finalization machinery can detect this case.
687 -- This early expansion is done only when the return statement is
688 -- not part of a handled sequence of statements.
690 if Nkind_In (Expr, N_Aggregate,
691 N_Extension_Aggregate)
692 and then Needs_Finalization (R_Type)
693 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
696 Make_Block_Statement (Loc,
697 Handled_Statement_Sequence =>
698 Make_Handled_Sequence_Of_Statements (Loc,
699 Statements => New_List (Relocate_Node (N)))));
705 Analyze_And_Resolve (Expr, R_Type);
706 Check_Limited_Return (Expr);
709 -- RETURN only allowed in SPARK as the last statement in function
711 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
713 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
714 or else Present (Next (N)))
716 Check_SPARK_Restriction
717 ("RETURN should be the last statement in function", N);
721 Check_SPARK_Restriction ("extended RETURN is not allowed", N);
723 -- Analyze parts specific to extended_return_statement:
726 Obj_Decl : constant Node_Id :=
727 Last (Return_Object_Declarations (N));
729 HSS : constant Node_Id := Handled_Statement_Sequence (N);
732 Expr := Expression (Obj_Decl);
734 -- Note: The check for OK_For_Limited_Init will happen in
735 -- Analyze_Object_Declaration; we treat it as a normal
736 -- object declaration.
738 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
741 Check_Return_Subtype_Indication (Obj_Decl);
743 if Present (HSS) then
746 if Present (Exception_Handlers (HSS)) then
748 -- ???Has_Nested_Block_With_Handler needs to be set.
749 -- Probably by creating an actual N_Block_Statement.
750 -- Probably in Expand.
756 -- Mark the return object as referenced, since the return is an
757 -- implicit reference of the object.
759 Set_Referenced (Defining_Identifier (Obj_Decl));
761 Check_References (Stm_Entity);
765 -- Case of Expr present
769 -- Defend against previous errors
771 and then Nkind (Expr) /= N_Empty
772 and then Present (Etype (Expr))
774 -- Apply constraint check. Note that this is done before the implicit
775 -- conversion of the expression done for anonymous access types to
776 -- ensure correct generation of the null-excluding check associated
777 -- with null-excluding expressions found in return statements.
779 Apply_Constraint_Check (Expr, R_Type);
781 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
782 -- type, apply an implicit conversion of the expression to that type
783 -- to force appropriate static and run-time accessibility checks.
785 if Ada_Version >= Ada_2005
786 and then Ekind (R_Type) = E_Anonymous_Access_Type
788 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
789 Analyze_And_Resolve (Expr, R_Type);
792 -- If the result type is class-wide, then check that the return
793 -- expression's type is not declared at a deeper level than the
794 -- function (RM05-6.5(5.6/2)).
796 if Ada_Version >= Ada_2005
797 and then Is_Class_Wide_Type (R_Type)
799 if Type_Access_Level (Etype (Expr)) >
800 Subprogram_Access_Level (Scope_Id)
803 ("level of return expression type is deeper than " &
804 "class-wide function!", Expr);
808 -- Check incorrect use of dynamically tagged expression
810 if Is_Tagged_Type (R_Type) then
811 Check_Dynamically_Tagged_Expression
817 -- ??? A real run-time accessibility check is needed in cases
818 -- involving dereferences of access parameters. For now we just
819 -- check the static cases.
821 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
822 and then Is_Immutably_Limited_Type (Etype (Scope_Id))
823 and then Object_Access_Level (Expr) >
824 Subprogram_Access_Level (Scope_Id)
827 -- Suppress the message in a generic, where the rewriting
830 if Inside_A_Generic then
835 Make_Raise_Program_Error (Loc,
836 Reason => PE_Accessibility_Check_Failed));
840 ("cannot return a local value by reference?", N);
842 ("\& will be raised at run time?",
843 N, Standard_Program_Error);
848 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
849 and then Null_Exclusion_Present (Parent (Scope_Id))
851 Apply_Compile_Time_Constraint_Error
853 Msg => "(Ada 2005) null not allowed for "
854 & "null-excluding return?",
855 Reason => CE_Null_Not_Allowed);
858 -- Apply checks suggested by AI05-0144 (dangerous order dependence)
860 Check_Order_Dependence;
862 end Analyze_Function_Return;
864 -------------------------------------
865 -- Analyze_Generic_Subprogram_Body --
866 -------------------------------------
868 procedure Analyze_Generic_Subprogram_Body
872 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
873 Kind : constant Entity_Kind := Ekind (Gen_Id);
879 -- Copy body and disable expansion while analyzing the generic For a
880 -- stub, do not copy the stub (which would load the proper body), this
881 -- will be done when the proper body is analyzed.
883 if Nkind (N) /= N_Subprogram_Body_Stub then
884 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
889 Spec := Specification (N);
891 -- Within the body of the generic, the subprogram is callable, and
892 -- behaves like the corresponding non-generic unit.
894 Body_Id := Defining_Entity (Spec);
896 if Kind = E_Generic_Procedure
897 and then Nkind (Spec) /= N_Procedure_Specification
899 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
902 elsif Kind = E_Generic_Function
903 and then Nkind (Spec) /= N_Function_Specification
905 Error_Msg_N ("invalid body for generic function ", Body_Id);
909 Set_Corresponding_Body (Gen_Decl, Body_Id);
911 if Has_Completion (Gen_Id)
912 and then Nkind (Parent (N)) /= N_Subunit
914 Error_Msg_N ("duplicate generic body", N);
917 Set_Has_Completion (Gen_Id);
920 if Nkind (N) = N_Subprogram_Body_Stub then
921 Set_Ekind (Defining_Entity (Specification (N)), Kind);
923 Set_Corresponding_Spec (N, Gen_Id);
926 if Nkind (Parent (N)) = N_Compilation_Unit then
927 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
930 -- Make generic parameters immediately visible in the body. They are
931 -- needed to process the formals declarations. Then make the formals
932 -- visible in a separate step.
938 First_Ent : Entity_Id;
941 First_Ent := First_Entity (Gen_Id);
944 while Present (E) and then not Is_Formal (E) loop
949 Set_Use (Generic_Formal_Declarations (Gen_Decl));
951 -- Now generic formals are visible, and the specification can be
952 -- analyzed, for subsequent conformance check.
954 Body_Id := Analyze_Subprogram_Specification (Spec);
956 -- Make formal parameters visible
960 -- E is the first formal parameter, we loop through the formals
961 -- installing them so that they will be visible.
963 Set_First_Entity (Gen_Id, E);
964 while Present (E) loop
970 -- Visible generic entity is callable within its own body
972 Set_Ekind (Gen_Id, Ekind (Body_Id));
973 Set_Ekind (Body_Id, E_Subprogram_Body);
974 Set_Convention (Body_Id, Convention (Gen_Id));
975 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
976 Set_Scope (Body_Id, Scope (Gen_Id));
977 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
979 if Nkind (N) = N_Subprogram_Body_Stub then
981 -- No body to analyze, so restore state of generic unit
983 Set_Ekind (Gen_Id, Kind);
984 Set_Ekind (Body_Id, Kind);
986 if Present (First_Ent) then
987 Set_First_Entity (Gen_Id, First_Ent);
994 -- If this is a compilation unit, it must be made visible explicitly,
995 -- because the compilation of the declaration, unlike other library
996 -- unit declarations, does not. If it is not a unit, the following
997 -- is redundant but harmless.
999 Set_Is_Immediately_Visible (Gen_Id);
1000 Reference_Body_Formals (Gen_Id, Body_Id);
1002 if Is_Child_Unit (Gen_Id) then
1003 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
1006 Set_Actual_Subtypes (N, Current_Scope);
1008 -- Deal with preconditions and postconditions. In formal verification
1009 -- mode, we keep pre- and postconditions attached to entities rather
1010 -- than inserted in the code, in order to facilitate a distinct
1011 -- treatment for them.
1013 if not Alfa_Mode then
1014 Process_PPCs (N, Gen_Id, Body_Id);
1017 -- If the generic unit carries pre- or post-conditions, copy them
1018 -- to the original generic tree, so that they are properly added
1019 -- to any instantiation.
1022 Orig : constant Node_Id := Original_Node (N);
1026 Cond := First (Declarations (N));
1027 while Present (Cond) loop
1028 if Nkind (Cond) = N_Pragma
1029 and then Pragma_Name (Cond) = Name_Check
1031 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1033 elsif Nkind (Cond) = N_Pragma
1034 and then Pragma_Name (Cond) = Name_Postcondition
1036 Set_Ekind (Defining_Entity (Orig), Ekind (Gen_Id));
1037 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1046 Analyze_Declarations (Declarations (N));
1048 Analyze (Handled_Statement_Sequence (N));
1050 Save_Global_References (Original_Node (N));
1052 -- Prior to exiting the scope, include generic formals again (if any
1053 -- are present) in the set of local entities.
1055 if Present (First_Ent) then
1056 Set_First_Entity (Gen_Id, First_Ent);
1059 Check_References (Gen_Id);
1062 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1064 Check_Subprogram_Order (N);
1066 -- Outside of its body, unit is generic again
1068 Set_Ekind (Gen_Id, Kind);
1069 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1072 Style.Check_Identifier (Body_Id, Gen_Id);
1076 end Analyze_Generic_Subprogram_Body;
1078 -----------------------------
1079 -- Analyze_Operator_Symbol --
1080 -----------------------------
1082 -- An operator symbol such as "+" or "and" may appear in context where the
1083 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1084 -- is just a string, as in (conjunction = "or"). In these cases the parser
1085 -- generates this node, and the semantics does the disambiguation. Other
1086 -- such case are actuals in an instantiation, the generic unit in an
1087 -- instantiation, and pragma arguments.
1089 procedure Analyze_Operator_Symbol (N : Node_Id) is
1090 Par : constant Node_Id := Parent (N);
1093 if (Nkind (Par) = N_Function_Call
1094 and then N = Name (Par))
1095 or else Nkind (Par) = N_Function_Instantiation
1096 or else (Nkind (Par) = N_Indexed_Component
1097 and then N = Prefix (Par))
1098 or else (Nkind (Par) = N_Pragma_Argument_Association
1099 and then not Is_Pragma_String_Literal (Par))
1100 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1101 or else (Nkind (Par) = N_Attribute_Reference
1102 and then Attribute_Name (Par) /= Name_Value)
1104 Find_Direct_Name (N);
1107 Change_Operator_Symbol_To_String_Literal (N);
1110 end Analyze_Operator_Symbol;
1112 -----------------------------------
1113 -- Analyze_Parameter_Association --
1114 -----------------------------------
1116 procedure Analyze_Parameter_Association (N : Node_Id) is
1118 Analyze (Explicit_Actual_Parameter (N));
1119 end Analyze_Parameter_Association;
1121 ----------------------------
1122 -- Analyze_Procedure_Call --
1123 ----------------------------
1125 procedure Analyze_Procedure_Call (N : Node_Id) is
1126 Loc : constant Source_Ptr := Sloc (N);
1127 P : constant Node_Id := Name (N);
1128 Actuals : constant List_Id := Parameter_Associations (N);
1132 procedure Analyze_Call_And_Resolve;
1133 -- Do Analyze and Resolve calls for procedure call
1134 -- At end, check illegal order dependence.
1136 ------------------------------
1137 -- Analyze_Call_And_Resolve --
1138 ------------------------------
1140 procedure Analyze_Call_And_Resolve is
1142 if Nkind (N) = N_Procedure_Call_Statement then
1144 Resolve (N, Standard_Void_Type);
1146 -- Apply checks suggested by AI05-0144
1148 Check_Order_Dependence;
1153 end Analyze_Call_And_Resolve;
1155 -- Start of processing for Analyze_Procedure_Call
1158 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1159 -- a procedure call or an entry call. The prefix may denote an access
1160 -- to subprogram type, in which case an implicit dereference applies.
1161 -- If the prefix is an indexed component (without implicit dereference)
1162 -- then the construct denotes a call to a member of an entire family.
1163 -- If the prefix is a simple name, it may still denote a call to a
1164 -- parameterless member of an entry family. Resolution of these various
1165 -- interpretations is delicate.
1169 -- If this is a call of the form Obj.Op, the call may have been
1170 -- analyzed and possibly rewritten into a block, in which case
1173 if Analyzed (N) then
1177 -- If there is an error analyzing the name (which may have been
1178 -- rewritten if the original call was in prefix notation) then error
1179 -- has been emitted already, mark node and return.
1182 or else Etype (Name (N)) = Any_Type
1184 Set_Etype (N, Any_Type);
1188 -- Otherwise analyze the parameters
1190 if Present (Actuals) then
1191 Actual := First (Actuals);
1193 while Present (Actual) loop
1195 Check_Parameterless_Call (Actual);
1200 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1202 if Nkind (P) = N_Attribute_Reference
1203 and then (Attribute_Name (P) = Name_Elab_Spec
1204 or else Attribute_Name (P) = Name_Elab_Body
1205 or else Attribute_Name (P) = Name_Elab_Subp_Body)
1207 if Present (Actuals) then
1209 ("no parameters allowed for this call", First (Actuals));
1213 Set_Etype (N, Standard_Void_Type);
1216 elsif Is_Entity_Name (P)
1217 and then Is_Record_Type (Etype (Entity (P)))
1218 and then Remote_AST_I_Dereference (P)
1222 elsif Is_Entity_Name (P)
1223 and then Ekind (Entity (P)) /= E_Entry_Family
1225 if Is_Access_Type (Etype (P))
1226 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1227 and then No (Actuals)
1228 and then Comes_From_Source (N)
1230 Error_Msg_N ("missing explicit dereference in call", N);
1233 Analyze_Call_And_Resolve;
1235 -- If the prefix is the simple name of an entry family, this is
1236 -- a parameterless call from within the task body itself.
1238 elsif Is_Entity_Name (P)
1239 and then Nkind (P) = N_Identifier
1240 and then Ekind (Entity (P)) = E_Entry_Family
1241 and then Present (Actuals)
1242 and then No (Next (First (Actuals)))
1244 -- Can be call to parameterless entry family. What appears to be the
1245 -- sole argument is in fact the entry index. Rewrite prefix of node
1246 -- accordingly. Source representation is unchanged by this
1250 Make_Indexed_Component (Loc,
1252 Make_Selected_Component (Loc,
1253 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1254 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1255 Expressions => Actuals);
1256 Set_Name (N, New_N);
1257 Set_Etype (New_N, Standard_Void_Type);
1258 Set_Parameter_Associations (N, No_List);
1259 Analyze_Call_And_Resolve;
1261 elsif Nkind (P) = N_Explicit_Dereference then
1262 if Ekind (Etype (P)) = E_Subprogram_Type then
1263 Analyze_Call_And_Resolve;
1265 Error_Msg_N ("expect access to procedure in call", P);
1268 -- The name can be a selected component or an indexed component that
1269 -- yields an access to subprogram. Such a prefix is legal if the call
1270 -- has parameter associations.
1272 elsif Is_Access_Type (Etype (P))
1273 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1275 if Present (Actuals) then
1276 Analyze_Call_And_Resolve;
1278 Error_Msg_N ("missing explicit dereference in call ", N);
1281 -- If not an access to subprogram, then the prefix must resolve to the
1282 -- name of an entry, entry family, or protected operation.
1284 -- For the case of a simple entry call, P is a selected component where
1285 -- the prefix is the task and the selector name is the entry. A call to
1286 -- a protected procedure will have the same syntax. If the protected
1287 -- object contains overloaded operations, the entity may appear as a
1288 -- function, the context will select the operation whose type is Void.
1290 elsif Nkind (P) = N_Selected_Component
1291 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1293 Ekind (Entity (Selector_Name (P))) = E_Procedure
1295 Ekind (Entity (Selector_Name (P))) = E_Function)
1297 Analyze_Call_And_Resolve;
1299 elsif Nkind (P) = N_Selected_Component
1300 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1301 and then Present (Actuals)
1302 and then No (Next (First (Actuals)))
1304 -- Can be call to parameterless entry family. What appears to be the
1305 -- sole argument is in fact the entry index. Rewrite prefix of node
1306 -- accordingly. Source representation is unchanged by this
1310 Make_Indexed_Component (Loc,
1311 Prefix => New_Copy (P),
1312 Expressions => Actuals);
1313 Set_Name (N, New_N);
1314 Set_Etype (New_N, Standard_Void_Type);
1315 Set_Parameter_Associations (N, No_List);
1316 Analyze_Call_And_Resolve;
1318 -- For the case of a reference to an element of an entry family, P is
1319 -- an indexed component whose prefix is a selected component (task and
1320 -- entry family), and whose index is the entry family index.
1322 elsif Nkind (P) = N_Indexed_Component
1323 and then Nkind (Prefix (P)) = N_Selected_Component
1324 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1326 Analyze_Call_And_Resolve;
1328 -- If the prefix is the name of an entry family, it is a call from
1329 -- within the task body itself.
1331 elsif Nkind (P) = N_Indexed_Component
1332 and then Nkind (Prefix (P)) = N_Identifier
1333 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1336 Make_Selected_Component (Loc,
1337 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1338 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1339 Rewrite (Prefix (P), New_N);
1341 Analyze_Call_And_Resolve;
1343 -- In Ada 2012. a qualified expression is a name, but it cannot be a
1344 -- procedure name, so the construct can only be a qualified expression.
1346 elsif Nkind (P) = N_Qualified_Expression
1347 and then Ada_Version >= Ada_2012
1349 Rewrite (N, Make_Code_Statement (Loc, Expression => P));
1352 -- Anything else is an error
1355 Error_Msg_N ("invalid procedure or entry call", N);
1357 end Analyze_Procedure_Call;
1359 ------------------------------
1360 -- Analyze_Return_Statement --
1361 ------------------------------
1363 procedure Analyze_Return_Statement (N : Node_Id) is
1365 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
1366 N_Extended_Return_Statement));
1368 Returns_Object : constant Boolean :=
1369 Nkind (N) = N_Extended_Return_Statement
1371 (Nkind (N) = N_Simple_Return_Statement
1372 and then Present (Expression (N)));
1373 -- True if we're returning something; that is, "return <expression>;"
1374 -- or "return Result : T [:= ...]". False for "return;". Used for error
1375 -- checking: If Returns_Object is True, N should apply to a function
1376 -- body; otherwise N should apply to a procedure body, entry body,
1377 -- accept statement, or extended return statement.
1379 function Find_What_It_Applies_To return Entity_Id;
1380 -- Find the entity representing the innermost enclosing body, accept
1381 -- statement, or extended return statement. If the result is a callable
1382 -- construct or extended return statement, then this will be the value
1383 -- of the Return_Applies_To attribute. Otherwise, the program is
1384 -- illegal. See RM-6.5(4/2).
1386 -----------------------------
1387 -- Find_What_It_Applies_To --
1388 -----------------------------
1390 function Find_What_It_Applies_To return Entity_Id is
1391 Result : Entity_Id := Empty;
1394 -- Loop outward through the Scope_Stack, skipping blocks, loops,
1395 -- and postconditions.
1397 for J in reverse 0 .. Scope_Stack.Last loop
1398 Result := Scope_Stack.Table (J).Entity;
1399 exit when not Ekind_In (Result, E_Block, E_Loop)
1400 and then Chars (Result) /= Name_uPostconditions;
1403 pragma Assert (Present (Result));
1405 end Find_What_It_Applies_To;
1407 -- Local declarations
1409 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1410 Kind : constant Entity_Kind := Ekind (Scope_Id);
1411 Loc : constant Source_Ptr := Sloc (N);
1412 Stm_Entity : constant Entity_Id :=
1414 (E_Return_Statement, Current_Scope, Loc, 'R');
1416 -- Start of processing for Analyze_Return_Statement
1419 Set_Return_Statement_Entity (N, Stm_Entity);
1421 Set_Etype (Stm_Entity, Standard_Void_Type);
1422 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1424 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1425 -- (4/2): an inner return statement will apply to this extended return.
1427 if Nkind (N) = N_Extended_Return_Statement then
1428 Push_Scope (Stm_Entity);
1431 -- Check that pragma No_Return is obeyed. Don't complain about the
1432 -- implicitly-generated return that is placed at the end.
1434 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1435 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1438 -- Warn on any unassigned OUT parameters if in procedure
1440 if Ekind (Scope_Id) = E_Procedure then
1441 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1444 -- Check that functions return objects, and other things do not
1446 if Kind = E_Function or else Kind = E_Generic_Function then
1447 if not Returns_Object then
1448 Error_Msg_N ("missing expression in return from function", N);
1451 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1452 if Returns_Object then
1453 Error_Msg_N ("procedure cannot return value (use function)", N);
1456 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1457 if Returns_Object then
1458 if Is_Protected_Type (Scope (Scope_Id)) then
1459 Error_Msg_N ("entry body cannot return value", N);
1461 Error_Msg_N ("accept statement cannot return value", N);
1465 elsif Kind = E_Return_Statement then
1467 -- We are nested within another return statement, which must be an
1468 -- extended_return_statement.
1470 if Returns_Object then
1472 ("extended_return_statement cannot return value; " &
1473 "use `""RETURN;""`", N);
1477 Error_Msg_N ("illegal context for return statement", N);
1480 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1481 Analyze_Function_Return (N);
1483 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1484 Set_Return_Present (Scope_Id);
1487 if Nkind (N) = N_Extended_Return_Statement then
1491 Kill_Current_Values (Last_Assignment_Only => True);
1492 Check_Unreachable_Code (N);
1493 end Analyze_Return_Statement;
1495 -------------------------------------
1496 -- Analyze_Simple_Return_Statement --
1497 -------------------------------------
1499 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1501 if Present (Expression (N)) then
1502 Mark_Coextensions (N, Expression (N));
1505 Analyze_Return_Statement (N);
1506 end Analyze_Simple_Return_Statement;
1508 -------------------------
1509 -- Analyze_Return_Type --
1510 -------------------------
1512 procedure Analyze_Return_Type (N : Node_Id) is
1513 Designator : constant Entity_Id := Defining_Entity (N);
1514 Typ : Entity_Id := Empty;
1517 -- Normal case where result definition does not indicate an error
1519 if Result_Definition (N) /= Error then
1520 if Nkind (Result_Definition (N)) = N_Access_Definition then
1521 Check_SPARK_Restriction
1522 ("access result is not allowed", Result_Definition (N));
1524 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1527 AD : constant Node_Id :=
1528 Access_To_Subprogram_Definition (Result_Definition (N));
1530 if Present (AD) and then Protected_Present (AD) then
1531 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1533 Typ := Access_Definition (N, Result_Definition (N));
1537 Set_Parent (Typ, Result_Definition (N));
1538 Set_Is_Local_Anonymous_Access (Typ);
1539 Set_Etype (Designator, Typ);
1541 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1543 Null_Exclusion_Static_Checks (N);
1545 -- Subtype_Mark case
1548 Find_Type (Result_Definition (N));
1549 Typ := Entity (Result_Definition (N));
1550 Set_Etype (Designator, Typ);
1552 -- Unconstrained array as result is not allowed in SPARK
1554 if Is_Array_Type (Typ)
1555 and then not Is_Constrained (Typ)
1557 Check_SPARK_Restriction
1558 ("returning an unconstrained array is not allowed",
1559 Result_Definition (N));
1562 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1564 Null_Exclusion_Static_Checks (N);
1566 -- If a null exclusion is imposed on the result type, then create
1567 -- a null-excluding itype (an access subtype) and use it as the
1568 -- function's Etype. Note that the null exclusion checks are done
1569 -- right before this, because they don't get applied to types that
1570 -- do not come from source.
1572 if Is_Access_Type (Typ)
1573 and then Null_Exclusion_Present (N)
1575 Set_Etype (Designator,
1576 Create_Null_Excluding_Itype
1579 Scope_Id => Scope (Current_Scope)));
1581 -- The new subtype must be elaborated before use because
1582 -- it is visible outside of the function. However its base
1583 -- type may not be frozen yet, so the reference that will
1584 -- force elaboration must be attached to the freezing of
1587 -- If the return specification appears on a proper body,
1588 -- the subtype will have been created already on the spec.
1590 if Is_Frozen (Typ) then
1591 if Nkind (Parent (N)) = N_Subprogram_Body
1592 and then Nkind (Parent (Parent (N))) = N_Subunit
1596 Build_Itype_Reference (Etype (Designator), Parent (N));
1600 Ensure_Freeze_Node (Typ);
1603 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
1605 Set_Itype (IR, Etype (Designator));
1606 Append_Freeze_Actions (Typ, New_List (IR));
1611 Set_Etype (Designator, Typ);
1614 if Ekind (Typ) = E_Incomplete_Type
1615 and then Is_Value_Type (Typ)
1619 elsif Ekind (Typ) = E_Incomplete_Type
1620 or else (Is_Class_Wide_Type (Typ)
1622 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1624 -- AI05-0151: Tagged incomplete types are allowed in all formal
1625 -- parts. Untagged incomplete types are not allowed in bodies.
1627 if Ada_Version >= Ada_2012 then
1628 if Is_Tagged_Type (Typ) then
1631 elsif Nkind_In (Parent (Parent (N)),
1637 ("invalid use of untagged incomplete type&",
1641 -- The type must be completed in the current package. This
1642 -- is checked at the end of the package declaraton, when
1643 -- Taft amemdment types are identified.
1645 if Ekind (Scope (Current_Scope)) = E_Package
1646 and then In_Private_Part (Scope (Current_Scope))
1648 Append_Elmt (Designator, Private_Dependents (Typ));
1653 ("invalid use of incomplete type&", Designator, Typ);
1658 -- Case where result definition does indicate an error
1661 Set_Etype (Designator, Any_Type);
1663 end Analyze_Return_Type;
1665 -----------------------------
1666 -- Analyze_Subprogram_Body --
1667 -----------------------------
1669 procedure Analyze_Subprogram_Body (N : Node_Id) is
1670 Loc : constant Source_Ptr := Sloc (N);
1671 Body_Spec : constant Node_Id := Specification (N);
1672 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
1675 if Debug_Flag_C then
1676 Write_Str ("==> subprogram body ");
1677 Write_Name (Chars (Body_Id));
1678 Write_Str (" from ");
1679 Write_Location (Loc);
1684 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1686 -- The real work is split out into the helper, so it can do "return;"
1687 -- without skipping the debug output:
1689 Analyze_Subprogram_Body_Helper (N);
1691 if Debug_Flag_C then
1693 Write_Str ("<== subprogram body ");
1694 Write_Name (Chars (Body_Id));
1695 Write_Str (" from ");
1696 Write_Location (Loc);
1699 end Analyze_Subprogram_Body;
1701 ------------------------------------
1702 -- Analyze_Subprogram_Body_Helper --
1703 ------------------------------------
1705 -- This procedure is called for regular subprogram bodies, generic bodies,
1706 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1707 -- specification matters, and is used to create a proper declaration for
1708 -- the subprogram, or to perform conformance checks.
1710 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
1711 Loc : constant Source_Ptr := Sloc (N);
1712 Body_Deleted : constant Boolean := False;
1713 Body_Spec : constant Node_Id := Specification (N);
1714 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1715 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1716 Conformant : Boolean;
1719 Prot_Typ : Entity_Id := Empty;
1720 Spec_Id : Entity_Id;
1721 Spec_Decl : Node_Id := Empty;
1723 Last_Real_Spec_Entity : Entity_Id := Empty;
1724 -- When we analyze a separate spec, the entity chain ends up containing
1725 -- the formals, as well as any itypes generated during analysis of the
1726 -- default expressions for parameters, or the arguments of associated
1727 -- precondition/postcondition pragmas (which are analyzed in the context
1728 -- of the spec since they have visibility on formals).
1730 -- These entities belong with the spec and not the body. However we do
1731 -- the analysis of the body in the context of the spec (again to obtain
1732 -- visibility to the formals), and all the entities generated during
1733 -- this analysis end up also chained to the entity chain of the spec.
1734 -- But they really belong to the body, and there is circuitry to move
1735 -- them from the spec to the body.
1737 -- However, when we do this move, we don't want to move the real spec
1738 -- entities (first para above) to the body. The Last_Real_Spec_Entity
1739 -- variable points to the last real spec entity, so we only move those
1740 -- chained beyond that point. It is initialized to Empty to deal with
1741 -- the case where there is no separate spec.
1743 procedure Check_Anonymous_Return;
1744 -- Ada 2005: if a function returns an access type that denotes a task,
1745 -- or a type that contains tasks, we must create a master entity for
1746 -- the anonymous type, which typically will be used in an allocator
1747 -- in the body of the function.
1749 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1750 -- Look ahead to recognize a pragma that may appear after the body.
1751 -- If there is a previous spec, check that it appears in the same
1752 -- declarative part. If the pragma is Inline_Always, perform inlining
1753 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1754 -- If the body acts as a spec, and inlining is required, we create a
1755 -- subprogram declaration for it, in order to attach the body to inline.
1756 -- If pragma does not appear after the body, check whether there is
1757 -- an inline pragma before any local declarations.
1759 procedure Check_Missing_Return;
1760 -- Checks for a function with a no return statements, and also performs
1761 -- the warning checks implemented by Check_Returns. In formal mode, also
1762 -- verify that a function ends with a RETURN and that a procedure does
1763 -- not contain any RETURN.
1765 function Disambiguate_Spec return Entity_Id;
1766 -- When a primitive is declared between the private view and the full
1767 -- view of a concurrent type which implements an interface, a special
1768 -- mechanism is used to find the corresponding spec of the primitive
1771 procedure Exchange_Limited_Views (Subp_Id : Entity_Id);
1772 -- Ada 2012 (AI05-0151): Detect whether the profile of Subp_Id contains
1773 -- incomplete types coming from a limited context and swap their limited
1774 -- views with the non-limited ones.
1776 function Is_Private_Concurrent_Primitive
1777 (Subp_Id : Entity_Id) return Boolean;
1778 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
1779 -- type that implements an interface and has a private view.
1781 procedure Set_Trivial_Subprogram (N : Node_Id);
1782 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
1783 -- subprogram whose body is being analyzed. N is the statement node
1784 -- causing the flag to be set, if the following statement is a return
1785 -- of an entity, we mark the entity as set in source to suppress any
1786 -- warning on the stylized use of function stubs with a dummy return.
1788 procedure Verify_Overriding_Indicator;
1789 -- If there was a previous spec, the entity has been entered in the
1790 -- current scope previously. If the body itself carries an overriding
1791 -- indicator, check that it is consistent with the known status of the
1794 ----------------------------
1795 -- Check_Anonymous_Return --
1796 ----------------------------
1798 procedure Check_Anonymous_Return is
1804 if Present (Spec_Id) then
1810 if Ekind (Scop) = E_Function
1811 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1812 and then not Is_Thunk (Scop)
1813 and then (Has_Task (Designated_Type (Etype (Scop)))
1815 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
1817 Is_Limited_Record (Designated_Type (Etype (Scop)))))
1818 and then Expander_Active
1820 -- Avoid cases with no tasking support
1822 and then RTE_Available (RE_Current_Master)
1823 and then not Restriction_Active (No_Task_Hierarchy)
1826 Make_Object_Declaration (Loc,
1827 Defining_Identifier =>
1828 Make_Defining_Identifier (Loc, Name_uMaster),
1829 Constant_Present => True,
1830 Object_Definition =>
1831 New_Reference_To (RTE (RE_Master_Id), Loc),
1833 Make_Explicit_Dereference (Loc,
1834 New_Reference_To (RTE (RE_Current_Master), Loc)));
1836 if Present (Declarations (N)) then
1837 Prepend (Decl, Declarations (N));
1839 Set_Declarations (N, New_List (Decl));
1842 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1843 Set_Has_Master_Entity (Scop);
1845 -- Now mark the containing scope as a task master
1848 while Nkind (Par) /= N_Compilation_Unit loop
1849 Par := Parent (Par);
1850 pragma Assert (Present (Par));
1852 -- If we fall off the top, we are at the outer level, and
1853 -- the environment task is our effective master, so nothing
1857 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
1859 Set_Is_Task_Master (Par, True);
1864 end Check_Anonymous_Return;
1866 -------------------------
1867 -- Check_Inline_Pragma --
1868 -------------------------
1870 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1874 function Is_Inline_Pragma (N : Node_Id) return Boolean;
1875 -- True when N is a pragma Inline or Inline_Always that applies
1876 -- to this subprogram.
1878 -----------------------
1879 -- Is_Inline_Pragma --
1880 -----------------------
1882 function Is_Inline_Pragma (N : Node_Id) return Boolean is
1885 Nkind (N) = N_Pragma
1887 (Pragma_Name (N) = Name_Inline_Always
1890 and then Pragma_Name (N) = Name_Inline))
1893 (Expression (First (Pragma_Argument_Associations (N))))
1895 end Is_Inline_Pragma;
1897 -- Start of processing for Check_Inline_Pragma
1900 if not Expander_Active then
1904 if Is_List_Member (N)
1905 and then Present (Next (N))
1906 and then Is_Inline_Pragma (Next (N))
1910 elsif Nkind (N) /= N_Subprogram_Body_Stub
1911 and then Present (Declarations (N))
1912 and then Is_Inline_Pragma (First (Declarations (N)))
1914 Prag := First (Declarations (N));
1920 if Present (Prag) then
1921 if Present (Spec_Id) then
1922 if In_Same_List (N, Unit_Declaration_Node (Spec_Id)) then
1927 -- Create a subprogram declaration, to make treatment uniform
1930 Subp : constant Entity_Id :=
1931 Make_Defining_Identifier (Loc, Chars (Body_Id));
1932 Decl : constant Node_Id :=
1933 Make_Subprogram_Declaration (Loc,
1935 New_Copy_Tree (Specification (N)));
1938 Set_Defining_Unit_Name (Specification (Decl), Subp);
1940 if Present (First_Formal (Body_Id)) then
1941 Plist := Copy_Parameter_List (Body_Id);
1942 Set_Parameter_Specifications
1943 (Specification (Decl), Plist);
1946 Insert_Before (N, Decl);
1949 Set_Has_Pragma_Inline (Subp);
1951 if Pragma_Name (Prag) = Name_Inline_Always then
1952 Set_Is_Inlined (Subp);
1953 Set_Has_Pragma_Inline_Always (Subp);
1960 end Check_Inline_Pragma;
1962 --------------------------
1963 -- Check_Missing_Return --
1964 --------------------------
1966 procedure Check_Missing_Return is
1968 Missing_Ret : Boolean;
1971 if Nkind (Body_Spec) = N_Function_Specification then
1972 if Present (Spec_Id) then
1978 if Return_Present (Id) then
1979 Check_Returns (HSS, 'F', Missing_Ret);
1982 Set_Has_Missing_Return (Id);
1985 elsif (Is_Generic_Subprogram (Id)
1986 or else not Is_Machine_Code_Subprogram (Id))
1987 and then not Body_Deleted
1989 Error_Msg_N ("missing RETURN statement in function body", N);
1992 -- If procedure with No_Return, check returns
1994 elsif Nkind (Body_Spec) = N_Procedure_Specification
1995 and then Present (Spec_Id)
1996 and then No_Return (Spec_Id)
1998 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
2001 -- Special checks in SPARK mode
2003 if Nkind (Body_Spec) = N_Function_Specification then
2005 -- In SPARK mode, last statement of a function should be a return
2008 Stat : constant Node_Id := Last_Source_Statement (HSS);
2011 and then not Nkind_In (Stat, N_Simple_Return_Statement,
2012 N_Extended_Return_Statement)
2014 Check_SPARK_Restriction
2015 ("last statement in function should be RETURN", Stat);
2019 -- In SPARK mode, verify that a procedure has no return
2021 elsif Nkind (Body_Spec) = N_Procedure_Specification then
2022 if Present (Spec_Id) then
2028 -- Would be nice to point to return statement here, can we
2029 -- borrow the Check_Returns procedure here ???
2031 if Return_Present (Id) then
2032 Check_SPARK_Restriction
2033 ("procedure should not have RETURN", N);
2036 end Check_Missing_Return;
2038 -----------------------
2039 -- Disambiguate_Spec --
2040 -----------------------
2042 function Disambiguate_Spec return Entity_Id is
2043 Priv_Spec : Entity_Id;
2046 procedure Replace_Types (To_Corresponding : Boolean);
2047 -- Depending on the flag, replace the type of formal parameters of
2048 -- Body_Id if it is a concurrent type implementing interfaces with
2049 -- the corresponding record type or the other way around.
2051 procedure Replace_Types (To_Corresponding : Boolean) is
2053 Formal_Typ : Entity_Id;
2056 Formal := First_Formal (Body_Id);
2057 while Present (Formal) loop
2058 Formal_Typ := Etype (Formal);
2060 if Is_Class_Wide_Type (Formal_Typ) then
2061 Formal_Typ := Root_Type (Formal_Typ);
2064 -- From concurrent type to corresponding record
2066 if To_Corresponding then
2067 if Is_Concurrent_Type (Formal_Typ)
2068 and then Present (Corresponding_Record_Type (Formal_Typ))
2069 and then Present (Interfaces (
2070 Corresponding_Record_Type (Formal_Typ)))
2073 Corresponding_Record_Type (Formal_Typ));
2076 -- From corresponding record to concurrent type
2079 if Is_Concurrent_Record_Type (Formal_Typ)
2080 and then Present (Interfaces (Formal_Typ))
2083 Corresponding_Concurrent_Type (Formal_Typ));
2087 Next_Formal (Formal);
2091 -- Start of processing for Disambiguate_Spec
2094 -- Try to retrieve the specification of the body as is. All error
2095 -- messages are suppressed because the body may not have a spec in
2096 -- its current state.
2098 Spec_N := Find_Corresponding_Spec (N, False);
2100 -- It is possible that this is the body of a primitive declared
2101 -- between a private and a full view of a concurrent type. The
2102 -- controlling parameter of the spec carries the concurrent type,
2103 -- not the corresponding record type as transformed by Analyze_
2104 -- Subprogram_Specification. In such cases, we undo the change
2105 -- made by the analysis of the specification and try to find the
2108 -- Note that wrappers already have their corresponding specs and
2109 -- bodies set during their creation, so if the candidate spec is
2110 -- a wrapper, then we definitely need to swap all types to their
2111 -- original concurrent status.
2114 or else Is_Primitive_Wrapper (Spec_N)
2116 -- Restore all references of corresponding record types to the
2117 -- original concurrent types.
2119 Replace_Types (To_Corresponding => False);
2120 Priv_Spec := Find_Corresponding_Spec (N, False);
2122 -- The current body truly belongs to a primitive declared between
2123 -- a private and a full view. We leave the modified body as is,
2124 -- and return the true spec.
2126 if Present (Priv_Spec)
2127 and then Is_Private_Primitive (Priv_Spec)
2132 -- In case that this is some sort of error, restore the original
2133 -- state of the body.
2135 Replace_Types (To_Corresponding => True);
2139 end Disambiguate_Spec;
2141 ----------------------------
2142 -- Exchange_Limited_Views --
2143 ----------------------------
2145 procedure Exchange_Limited_Views (Subp_Id : Entity_Id) is
2146 procedure Detect_And_Exchange (Id : Entity_Id);
2147 -- Determine whether Id's type denotes an incomplete type associated
2148 -- with a limited with clause and exchange the limited view with the
2151 -------------------------
2152 -- Detect_And_Exchange --
2153 -------------------------
2155 procedure Detect_And_Exchange (Id : Entity_Id) is
2156 Typ : constant Entity_Id := Etype (Id);
2159 if Ekind (Typ) = E_Incomplete_Type
2160 and then From_With_Type (Typ)
2161 and then Present (Non_Limited_View (Typ))
2163 Set_Etype (Id, Non_Limited_View (Typ));
2165 end Detect_And_Exchange;
2171 -- Start of processing for Exchange_Limited_Views
2174 if No (Subp_Id) then
2177 -- Do not process subprogram bodies as they already use the non-
2178 -- limited view of types.
2180 elsif not Ekind_In (Subp_Id, E_Function, E_Procedure) then
2184 -- Examine all formals and swap views when applicable
2186 Formal := First_Formal (Subp_Id);
2187 while Present (Formal) loop
2188 Detect_And_Exchange (Formal);
2190 Next_Formal (Formal);
2193 -- Process the return type of a function
2195 if Ekind (Subp_Id) = E_Function then
2196 Detect_And_Exchange (Subp_Id);
2198 end Exchange_Limited_Views;
2200 -------------------------------------
2201 -- Is_Private_Concurrent_Primitive --
2202 -------------------------------------
2204 function Is_Private_Concurrent_Primitive
2205 (Subp_Id : Entity_Id) return Boolean
2207 Formal_Typ : Entity_Id;
2210 if Present (First_Formal (Subp_Id)) then
2211 Formal_Typ := Etype (First_Formal (Subp_Id));
2213 if Is_Concurrent_Record_Type (Formal_Typ) then
2214 if Is_Class_Wide_Type (Formal_Typ) then
2215 Formal_Typ := Root_Type (Formal_Typ);
2218 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
2221 -- The type of the first formal is a concurrent tagged type with
2225 Is_Concurrent_Type (Formal_Typ)
2226 and then Is_Tagged_Type (Formal_Typ)
2227 and then Has_Private_Declaration (Formal_Typ);
2231 end Is_Private_Concurrent_Primitive;
2233 ----------------------------
2234 -- Set_Trivial_Subprogram --
2235 ----------------------------
2237 procedure Set_Trivial_Subprogram (N : Node_Id) is
2238 Nxt : constant Node_Id := Next (N);
2241 Set_Is_Trivial_Subprogram (Body_Id);
2243 if Present (Spec_Id) then
2244 Set_Is_Trivial_Subprogram (Spec_Id);
2248 and then Nkind (Nxt) = N_Simple_Return_Statement
2249 and then No (Next (Nxt))
2250 and then Present (Expression (Nxt))
2251 and then Is_Entity_Name (Expression (Nxt))
2253 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
2255 end Set_Trivial_Subprogram;
2257 ---------------------------------
2258 -- Verify_Overriding_Indicator --
2259 ---------------------------------
2261 procedure Verify_Overriding_Indicator is
2263 if Must_Override (Body_Spec) then
2264 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
2265 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2269 elsif not Present (Overridden_Operation (Spec_Id)) then
2271 ("subprogram& is not overriding", Body_Spec, Spec_Id);
2274 elsif Must_Not_Override (Body_Spec) then
2275 if Present (Overridden_Operation (Spec_Id)) then
2277 ("subprogram& overrides inherited operation",
2278 Body_Spec, Spec_Id);
2280 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
2281 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2284 ("subprogram & overrides predefined operator ",
2285 Body_Spec, Spec_Id);
2287 -- If this is not a primitive operation or protected subprogram,
2288 -- then the overriding indicator is altogether illegal.
2290 elsif not Is_Primitive (Spec_Id)
2291 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
2294 ("overriding indicator only allowed " &
2295 "if subprogram is primitive",
2300 and then Present (Overridden_Operation (Spec_Id))
2302 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2303 Style.Missing_Overriding (N, Body_Id);
2306 and then Can_Override_Operator (Spec_Id)
2307 and then not Is_Predefined_File_Name
2308 (Unit_File_Name (Get_Source_Unit (Spec_Id)))
2310 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2311 Style.Missing_Overriding (N, Body_Id);
2313 end Verify_Overriding_Indicator;
2315 -- Start of processing for Analyze_Subprogram_Body_Helper
2318 -- Generic subprograms are handled separately. They always have a
2319 -- generic specification. Determine whether current scope has a
2320 -- previous declaration.
2322 -- If the subprogram body is defined within an instance of the same
2323 -- name, the instance appears as a package renaming, and will be hidden
2324 -- within the subprogram.
2326 if Present (Prev_Id)
2327 and then not Is_Overloadable (Prev_Id)
2328 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
2329 or else Comes_From_Source (Prev_Id))
2331 if Is_Generic_Subprogram (Prev_Id) then
2333 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2334 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2336 Analyze_Generic_Subprogram_Body (N, Spec_Id);
2338 if Nkind (N) = N_Subprogram_Body then
2339 HSS := Handled_Statement_Sequence (N);
2340 Check_Missing_Return;
2346 -- Previous entity conflicts with subprogram name. Attempting to
2347 -- enter name will post error.
2349 Enter_Name (Body_Id);
2353 -- Non-generic case, find the subprogram declaration, if one was seen,
2354 -- or enter new overloaded entity in the current scope. If the
2355 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
2356 -- part of the context of one of its subunits. No need to redo the
2359 elsif Prev_Id = Body_Id
2360 and then Has_Completion (Body_Id)
2365 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2367 if Nkind (N) = N_Subprogram_Body_Stub
2368 or else No (Corresponding_Spec (N))
2370 if Is_Private_Concurrent_Primitive (Body_Id) then
2371 Spec_Id := Disambiguate_Spec;
2373 Spec_Id := Find_Corresponding_Spec (N);
2376 -- If this is a duplicate body, no point in analyzing it
2378 if Error_Posted (N) then
2382 -- A subprogram body should cause freezing of its own declaration,
2383 -- but if there was no previous explicit declaration, then the
2384 -- subprogram will get frozen too late (there may be code within
2385 -- the body that depends on the subprogram having been frozen,
2386 -- such as uses of extra formals), so we force it to be frozen
2387 -- here. Same holds if the body and spec are compilation units.
2388 -- Finally, if the return type is an anonymous access to protected
2389 -- subprogram, it must be frozen before the body because its
2390 -- expansion has generated an equivalent type that is used when
2391 -- elaborating the body.
2393 -- An exception in the case of Ada 2012, AI05-177: The bodies
2394 -- created for expression functions do not freeze.
2397 and then Nkind (Original_Node (N)) /= N_Expression_Function
2399 Freeze_Before (N, Body_Id);
2401 elsif Nkind (Parent (N)) = N_Compilation_Unit then
2402 Freeze_Before (N, Spec_Id);
2404 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
2405 Freeze_Before (N, Etype (Body_Id));
2409 Spec_Id := Corresponding_Spec (N);
2413 -- Do not inline any subprogram that contains nested subprograms, since
2414 -- the backend inlining circuit seems to generate uninitialized
2415 -- references in this case. We know this happens in the case of front
2416 -- end ZCX support, but it also appears it can happen in other cases as
2417 -- well. The backend often rejects attempts to inline in the case of
2418 -- nested procedures anyway, so little if anything is lost by this.
2419 -- Note that this is test is for the benefit of the back-end. There is
2420 -- a separate test for front-end inlining that also rejects nested
2423 -- Do not do this test if errors have been detected, because in some
2424 -- error cases, this code blows up, and we don't need it anyway if
2425 -- there have been errors, since we won't get to the linker anyway.
2427 if Comes_From_Source (Body_Id)
2428 and then Serious_Errors_Detected = 0
2432 P_Ent := Scope (P_Ent);
2433 exit when No (P_Ent) or else P_Ent = Standard_Standard;
2435 if Is_Subprogram (P_Ent) then
2436 Set_Is_Inlined (P_Ent, False);
2438 if Comes_From_Source (P_Ent)
2439 and then Has_Pragma_Inline (P_Ent)
2442 ("cannot inline& (nested subprogram)?",
2449 Check_Inline_Pragma (Spec_Id);
2451 -- Deal with special case of a fully private operation in the body of
2452 -- the protected type. We must create a declaration for the subprogram,
2453 -- in order to attach the protected subprogram that will be used in
2454 -- internal calls. We exclude compiler generated bodies from the
2455 -- expander since the issue does not arise for those cases.
2458 and then Comes_From_Source (N)
2459 and then Is_Protected_Type (Current_Scope)
2461 Spec_Id := Build_Private_Protected_Declaration (N);
2464 -- If a separate spec is present, then deal with freezing issues
2466 if Present (Spec_Id) then
2467 Spec_Decl := Unit_Declaration_Node (Spec_Id);
2468 Verify_Overriding_Indicator;
2470 -- In general, the spec will be frozen when we start analyzing the
2471 -- body. However, for internally generated operations, such as
2472 -- wrapper functions for inherited operations with controlling
2473 -- results, the spec may not have been frozen by the time we expand
2474 -- the freeze actions that include the bodies. In particular, extra
2475 -- formals for accessibility or for return-in-place may need to be
2476 -- generated. Freeze nodes, if any, are inserted before the current
2477 -- body. These freeze actions are also needed in ASIS mode to enable
2478 -- the proper back-annotations.
2480 if not Is_Frozen (Spec_Id)
2481 and then (Expander_Active or ASIS_Mode)
2483 -- Force the generation of its freezing node to ensure proper
2484 -- management of access types in the backend.
2486 -- This is definitely needed for some cases, but it is not clear
2487 -- why, to be investigated further???
2489 Set_Has_Delayed_Freeze (Spec_Id);
2490 Freeze_Before (N, Spec_Id);
2494 -- Mark presence of postcondition procedure in current scope and mark
2495 -- the procedure itself as needing debug info. The latter is important
2496 -- when analyzing decision coverage (for example, for MC/DC coverage).
2498 if Chars (Body_Id) = Name_uPostconditions then
2499 Set_Has_Postconditions (Current_Scope);
2500 Set_Debug_Info_Needed (Body_Id);
2503 -- Place subprogram on scope stack, and make formals visible. If there
2504 -- is a spec, the visible entity remains that of the spec.
2506 if Present (Spec_Id) then
2507 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
2509 if Is_Child_Unit (Spec_Id) then
2510 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
2514 Style.Check_Identifier (Body_Id, Spec_Id);
2517 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2518 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2520 if Is_Abstract_Subprogram (Spec_Id) then
2521 Error_Msg_N ("an abstract subprogram cannot have a body", N);
2525 Set_Convention (Body_Id, Convention (Spec_Id));
2526 Set_Has_Completion (Spec_Id);
2528 if Is_Protected_Type (Scope (Spec_Id)) then
2529 Prot_Typ := Scope (Spec_Id);
2532 -- If this is a body generated for a renaming, do not check for
2533 -- full conformance. The check is redundant, because the spec of
2534 -- the body is a copy of the spec in the renaming declaration,
2535 -- and the test can lead to spurious errors on nested defaults.
2537 if Present (Spec_Decl)
2538 and then not Comes_From_Source (N)
2540 (Nkind (Original_Node (Spec_Decl)) =
2541 N_Subprogram_Renaming_Declaration
2542 or else (Present (Corresponding_Body (Spec_Decl))
2544 Nkind (Unit_Declaration_Node
2545 (Corresponding_Body (Spec_Decl))) =
2546 N_Subprogram_Renaming_Declaration))
2550 -- Conversely, the spec may have been generated for specless body
2551 -- with an inline pragma.
2553 elsif Comes_From_Source (N)
2554 and then not Comes_From_Source (Spec_Id)
2555 and then Has_Pragma_Inline (Spec_Id)
2562 Fully_Conformant, True, Conformant, Body_Id);
2565 -- If the body is not fully conformant, we have to decide if we
2566 -- should analyze it or not. If it has a really messed up profile
2567 -- then we probably should not analyze it, since we will get too
2568 -- many bogus messages.
2570 -- Our decision is to go ahead in the non-fully conformant case
2571 -- only if it is at least mode conformant with the spec. Note
2572 -- that the call to Check_Fully_Conformant has issued the proper
2573 -- error messages to complain about the lack of conformance.
2576 and then not Mode_Conformant (Body_Id, Spec_Id)
2582 if Spec_Id /= Body_Id then
2583 Reference_Body_Formals (Spec_Id, Body_Id);
2586 if Nkind (N) /= N_Subprogram_Body_Stub then
2587 Set_Corresponding_Spec (N, Spec_Id);
2589 -- Ada 2005 (AI-345): If the operation is a primitive operation
2590 -- of a concurrent type, the type of the first parameter has been
2591 -- replaced with the corresponding record, which is the proper
2592 -- run-time structure to use. However, within the body there may
2593 -- be uses of the formals that depend on primitive operations
2594 -- of the type (in particular calls in prefixed form) for which
2595 -- we need the original concurrent type. The operation may have
2596 -- several controlling formals, so the replacement must be done
2599 if Comes_From_Source (Spec_Id)
2600 and then Present (First_Entity (Spec_Id))
2601 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2602 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2604 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2607 (Corresponding_Concurrent_Type
2608 (Etype (First_Entity (Spec_Id))))
2611 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2615 Form := First_Formal (Spec_Id);
2616 while Present (Form) loop
2617 if Etype (Form) = Typ then
2618 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2626 -- Make the formals visible, and place subprogram on scope stack.
2627 -- This is also the point at which we set Last_Real_Spec_Entity
2628 -- to mark the entities which will not be moved to the body.
2630 Install_Formals (Spec_Id);
2631 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2632 Push_Scope (Spec_Id);
2634 -- Make sure that the subprogram is immediately visible. For
2635 -- child units that have no separate spec this is indispensable.
2636 -- Otherwise it is safe albeit redundant.
2638 Set_Is_Immediately_Visible (Spec_Id);
2641 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2642 Set_Ekind (Body_Id, E_Subprogram_Body);
2643 Set_Scope (Body_Id, Scope (Spec_Id));
2644 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2646 -- Case of subprogram body with no previous spec
2649 -- Check for style warning required
2653 -- Only apply check for source level subprograms for which checks
2654 -- have not been suppressed.
2656 and then Comes_From_Source (Body_Id)
2657 and then not Suppress_Style_Checks (Body_Id)
2659 -- No warnings within an instance
2661 and then not In_Instance
2663 -- No warnings for expression functions
2665 and then Nkind (Original_Node (N)) /= N_Expression_Function
2667 Style.Body_With_No_Spec (N);
2670 New_Overloaded_Entity (Body_Id);
2672 if Nkind (N) /= N_Subprogram_Body_Stub then
2673 Set_Acts_As_Spec (N);
2674 Generate_Definition (Body_Id);
2675 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
2677 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2678 Install_Formals (Body_Id);
2679 Push_Scope (Body_Id);
2682 -- For stubs and bodies with no previous spec, generate references to
2685 Generate_Reference_To_Formals (Body_Id);
2688 -- If the return type is an anonymous access type whose designated type
2689 -- is the limited view of a class-wide type and the non-limited view is
2690 -- available, update the return type accordingly.
2692 if Ada_Version >= Ada_2005
2693 and then Comes_From_Source (N)
2700 Rtyp := Etype (Current_Scope);
2702 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2703 Etyp := Directly_Designated_Type (Rtyp);
2705 if Is_Class_Wide_Type (Etyp)
2706 and then From_With_Type (Etyp)
2708 Set_Directly_Designated_Type
2709 (Etype (Current_Scope), Available_View (Etyp));
2715 -- If this is the proper body of a stub, we must verify that the stub
2716 -- conforms to the body, and to the previous spec if one was present.
2717 -- We know already that the body conforms to that spec. This test is
2718 -- only required for subprograms that come from source.
2720 if Nkind (Parent (N)) = N_Subunit
2721 and then Comes_From_Source (N)
2722 and then not Error_Posted (Body_Id)
2723 and then Nkind (Corresponding_Stub (Parent (N))) =
2724 N_Subprogram_Body_Stub
2727 Old_Id : constant Entity_Id :=
2729 (Specification (Corresponding_Stub (Parent (N))));
2731 Conformant : Boolean := False;
2734 if No (Spec_Id) then
2735 Check_Fully_Conformant (Body_Id, Old_Id);
2739 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2741 if not Conformant then
2743 -- The stub was taken to be a new declaration. Indicate that
2746 Set_Has_Completion (Old_Id, False);
2752 Set_Has_Completion (Body_Id);
2753 Check_Eliminated (Body_Id);
2755 if Nkind (N) = N_Subprogram_Body_Stub then
2758 elsif Present (Spec_Id)
2759 and then Expander_Active
2761 (Has_Pragma_Inline_Always (Spec_Id)
2762 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2764 Build_Body_To_Inline (N, Spec_Id);
2767 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2768 -- of the specification we have to install the private withed units.
2769 -- This holds for child units as well.
2771 if Is_Compilation_Unit (Body_Id)
2772 or else Nkind (Parent (N)) = N_Compilation_Unit
2774 Install_Private_With_Clauses (Body_Id);
2777 Check_Anonymous_Return;
2779 -- Set the Protected_Formal field of each extra formal of the protected
2780 -- subprogram to reference the corresponding extra formal of the
2781 -- subprogram that implements it. For regular formals this occurs when
2782 -- the protected subprogram's declaration is expanded, but the extra
2783 -- formals don't get created until the subprogram is frozen. We need to
2784 -- do this before analyzing the protected subprogram's body so that any
2785 -- references to the original subprogram's extra formals will be changed
2786 -- refer to the implementing subprogram's formals (see Expand_Formal).
2788 if Present (Spec_Id)
2789 and then Is_Protected_Type (Scope (Spec_Id))
2790 and then Present (Protected_Body_Subprogram (Spec_Id))
2793 Impl_Subp : constant Entity_Id :=
2794 Protected_Body_Subprogram (Spec_Id);
2795 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2796 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2798 while Present (Prot_Ext_Formal) loop
2799 pragma Assert (Present (Impl_Ext_Formal));
2800 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2801 Next_Formal_With_Extras (Prot_Ext_Formal);
2802 Next_Formal_With_Extras (Impl_Ext_Formal);
2807 -- Now we can go on to analyze the body
2809 HSS := Handled_Statement_Sequence (N);
2810 Set_Actual_Subtypes (N, Current_Scope);
2812 -- Deal with preconditions and postconditions. In formal verification
2813 -- mode, we keep pre- and postconditions attached to entities rather
2814 -- than inserted in the code, in order to facilitate a distinct
2815 -- treatment for them.
2817 if not Alfa_Mode then
2818 Process_PPCs (N, Spec_Id, Body_Id);
2821 -- Add a declaration for the Protection object, renaming declarations
2822 -- for discriminals and privals and finally a declaration for the entry
2823 -- family index (if applicable). This form of early expansion is done
2824 -- when the Expander is active because Install_Private_Data_Declarations
2825 -- references entities which were created during regular expansion. The
2826 -- body may be the rewritting of an expression function, and we need to
2827 -- verify that the original node is in the source.
2829 if Full_Expander_Active
2830 and then Comes_From_Source (Original_Node (N))
2831 and then Present (Prot_Typ)
2832 and then Present (Spec_Id)
2833 and then not Is_Eliminated (Spec_Id)
2835 Install_Private_Data_Declarations
2836 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2839 -- Ada 2012 (AI05-0151): Incomplete types coming from a limited context
2840 -- may now appear in parameter and result profiles. Since the analysis
2841 -- of a subprogram body may use the parameter and result profile of the
2842 -- spec, swap any limited views with their non-limited counterpart.
2844 if Ada_Version >= Ada_2012 then
2845 Exchange_Limited_Views (Spec_Id);
2848 -- Analyze the declarations (this call will analyze the precondition
2849 -- Check pragmas we prepended to the list, as well as the declaration
2850 -- of the _Postconditions procedure).
2852 Analyze_Declarations (Declarations (N));
2854 -- Check completion, and analyze the statements
2857 Inspect_Deferred_Constant_Completion (Declarations (N));
2860 -- Deal with end of scope processing for the body
2862 Process_End_Label (HSS, 't', Current_Scope);
2864 Check_Subprogram_Order (N);
2865 Set_Analyzed (Body_Id);
2867 -- If we have a separate spec, then the analysis of the declarations
2868 -- caused the entities in the body to be chained to the spec id, but
2869 -- we want them chained to the body id. Only the formal parameters
2870 -- end up chained to the spec id in this case.
2872 if Present (Spec_Id) then
2874 -- We must conform to the categorization of our spec
2876 Validate_Categorization_Dependency (N, Spec_Id);
2878 -- And if this is a child unit, the parent units must conform
2880 if Is_Child_Unit (Spec_Id) then
2881 Validate_Categorization_Dependency
2882 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2885 -- Here is where we move entities from the spec to the body
2887 -- Case where there are entities that stay with the spec
2889 if Present (Last_Real_Spec_Entity) then
2891 -- No body entities (happens when the only real spec entities come
2892 -- from precondition and postcondition pragmas).
2894 if No (Last_Entity (Body_Id)) then
2896 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2898 -- Body entities present (formals), so chain stuff past them
2902 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2905 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2906 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2907 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2909 -- Case where there are no spec entities, in this case there can be
2910 -- no body entities either, so just move everything.
2913 pragma Assert (No (Last_Entity (Body_Id)));
2914 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2915 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2916 Set_First_Entity (Spec_Id, Empty);
2917 Set_Last_Entity (Spec_Id, Empty);
2921 Check_Missing_Return;
2923 -- Now we are going to check for variables that are never modified in
2924 -- the body of the procedure. But first we deal with a special case
2925 -- where we want to modify this check. If the body of the subprogram
2926 -- starts with a raise statement or its equivalent, or if the body
2927 -- consists entirely of a null statement, then it is pretty obvious
2928 -- that it is OK to not reference the parameters. For example, this
2929 -- might be the following common idiom for a stubbed function:
2930 -- statement of the procedure raises an exception. In particular this
2931 -- deals with the common idiom of a stubbed function, which might
2932 -- appear as something like:
2934 -- function F (A : Integer) return Some_Type;
2937 -- raise Program_Error;
2941 -- Here the purpose of X is simply to satisfy the annoying requirement
2942 -- in Ada that there be at least one return, and we certainly do not
2943 -- want to go posting warnings on X that it is not initialized! On
2944 -- the other hand, if X is entirely unreferenced that should still
2947 -- What we do is to detect these cases, and if we find them, flag the
2948 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2949 -- suppress unwanted warnings. For the case of the function stub above
2950 -- we have a special test to set X as apparently assigned to suppress
2957 -- Skip initial labels (for one thing this occurs when we are in
2958 -- front end ZCX mode, but in any case it is irrelevant), and also
2959 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2961 Stm := First (Statements (HSS));
2962 while Nkind (Stm) = N_Label
2963 or else Nkind (Stm) in N_Push_xxx_Label
2968 -- Do the test on the original statement before expansion
2971 Ostm : constant Node_Id := Original_Node (Stm);
2974 -- If explicit raise statement, turn on flag
2976 if Nkind (Ostm) = N_Raise_Statement then
2977 Set_Trivial_Subprogram (Stm);
2979 -- If null statement, and no following statements, turn on flag
2981 elsif Nkind (Stm) = N_Null_Statement
2982 and then Comes_From_Source (Stm)
2983 and then No (Next (Stm))
2985 Set_Trivial_Subprogram (Stm);
2987 -- Check for explicit call cases which likely raise an exception
2989 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2990 if Is_Entity_Name (Name (Ostm)) then
2992 Ent : constant Entity_Id := Entity (Name (Ostm));
2995 -- If the procedure is marked No_Return, then likely it
2996 -- raises an exception, but in any case it is not coming
2997 -- back here, so turn on the flag.
3000 and then Ekind (Ent) = E_Procedure
3001 and then No_Return (Ent)
3003 Set_Trivial_Subprogram (Stm);
3011 -- Check for variables that are never modified
3017 -- If there is a separate spec, then transfer Never_Set_In_Source
3018 -- flags from out parameters to the corresponding entities in the
3019 -- body. The reason we do that is we want to post error flags on
3020 -- the body entities, not the spec entities.
3022 if Present (Spec_Id) then
3023 E1 := First_Entity (Spec_Id);
3024 while Present (E1) loop
3025 if Ekind (E1) = E_Out_Parameter then
3026 E2 := First_Entity (Body_Id);
3027 while Present (E2) loop
3028 exit when Chars (E1) = Chars (E2);
3032 if Present (E2) then
3033 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
3041 -- Check references in body unless it was deleted. Note that the
3042 -- check of Body_Deleted here is not just for efficiency, it is
3043 -- necessary to avoid junk warnings on formal parameters.
3045 if not Body_Deleted then
3046 Check_References (Body_Id);
3049 end Analyze_Subprogram_Body_Helper;
3051 ------------------------------------
3052 -- Analyze_Subprogram_Declaration --
3053 ------------------------------------
3055 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
3056 Loc : constant Source_Ptr := Sloc (N);
3057 Scop : constant Entity_Id := Current_Scope;
3058 Designator : Entity_Id;
3060 Null_Body : Node_Id := Empty;
3062 -- Start of processing for Analyze_Subprogram_Declaration
3065 -- Null procedures are not allowed in SPARK
3067 if Nkind (Specification (N)) = N_Procedure_Specification
3068 and then Null_Present (Specification (N))
3070 Check_SPARK_Restriction ("null procedure is not allowed", N);
3073 -- For a null procedure, capture the profile before analysis, for
3074 -- expansion at the freeze point and at each point of call. The body
3075 -- will only be used if the procedure has preconditions. In that case
3076 -- the body is analyzed at the freeze point.
3078 if Nkind (Specification (N)) = N_Procedure_Specification
3079 and then Null_Present (Specification (N))
3080 and then Expander_Active
3083 Make_Subprogram_Body (Loc,
3085 New_Copy_Tree (Specification (N)),
3088 Handled_Statement_Sequence =>
3089 Make_Handled_Sequence_Of_Statements (Loc,
3090 Statements => New_List (Make_Null_Statement (Loc))));
3092 -- Create new entities for body and formals
3094 Set_Defining_Unit_Name (Specification (Null_Body),
3095 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))));
3096 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
3098 Form := First (Parameter_Specifications (Specification (Null_Body)));
3099 while Present (Form) loop
3100 Set_Defining_Identifier (Form,
3101 Make_Defining_Identifier (Loc,
3102 Chars (Defining_Identifier (Form))));
3104 -- Resolve the types of the formals now, because the freeze point
3105 -- may appear in a different context, e.g. an instantiation.
3107 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
3108 Find_Type (Parameter_Type (Form));
3111 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
3113 Find_Type (Subtype_Mark (Parameter_Type (Form)));
3117 -- the case of a null procedure with a formal that is an
3118 -- access_to_subprogram type, and that is used as an actual
3119 -- in an instantiation is left to the enthusiastic reader.
3127 if Is_Protected_Type (Current_Scope) then
3128 Error_Msg_N ("protected operation cannot be a null procedure", N);
3132 Designator := Analyze_Subprogram_Specification (Specification (N));
3133 Generate_Definition (Designator);
3134 -- ??? why this call, already in Analyze_Subprogram_Specification
3136 if Debug_Flag_C then
3137 Write_Str ("==> subprogram spec ");
3138 Write_Name (Chars (Designator));
3139 Write_Str (" from ");
3140 Write_Location (Sloc (N));
3145 if Nkind (Specification (N)) = N_Procedure_Specification
3146 and then Null_Present (Specification (N))
3148 Set_Has_Completion (Designator);
3150 if Present (Null_Body) then
3151 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
3152 Set_Body_To_Inline (N, Null_Body);
3153 Set_Is_Inlined (Designator);
3157 Validate_RCI_Subprogram_Declaration (N);
3158 New_Overloaded_Entity (Designator);
3159 Check_Delayed_Subprogram (Designator);
3161 -- If the type of the first formal of the current subprogram is a
3162 -- nongeneric tagged private type, mark the subprogram as being a
3163 -- private primitive. Ditto if this is a function with controlling
3164 -- result, and the return type is currently private. In both cases,
3165 -- the type of the controlling argument or result must be in the
3166 -- current scope for the operation to be primitive.
3168 if Has_Controlling_Result (Designator)
3169 and then Is_Private_Type (Etype (Designator))
3170 and then Scope (Etype (Designator)) = Current_Scope
3171 and then not Is_Generic_Actual_Type (Etype (Designator))
3173 Set_Is_Private_Primitive (Designator);
3175 elsif Present (First_Formal (Designator)) then
3177 Formal_Typ : constant Entity_Id :=
3178 Etype (First_Formal (Designator));
3180 Set_Is_Private_Primitive (Designator,
3181 Is_Tagged_Type (Formal_Typ)
3182 and then Scope (Formal_Typ) = Current_Scope
3183 and then Is_Private_Type (Formal_Typ)
3184 and then not Is_Generic_Actual_Type (Formal_Typ));
3188 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
3191 if Ada_Version >= Ada_2005
3192 and then Comes_From_Source (N)
3193 and then Is_Dispatching_Operation (Designator)
3200 if Has_Controlling_Result (Designator) then
3201 Etyp := Etype (Designator);
3204 E := First_Entity (Designator);
3206 and then Is_Formal (E)
3207 and then not Is_Controlling_Formal (E)
3215 if Is_Access_Type (Etyp) then
3216 Etyp := Directly_Designated_Type (Etyp);
3219 if Is_Interface (Etyp)
3220 and then not Is_Abstract_Subprogram (Designator)
3221 and then not (Ekind (Designator) = E_Procedure
3222 and then Null_Present (Specification (N)))
3224 Error_Msg_Name_1 := Chars (Defining_Entity (N));
3226 ("(Ada 2005) interface subprogram % must be abstract or null",
3232 -- What is the following code for, it used to be
3234 -- ??? Set_Suppress_Elaboration_Checks
3235 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
3237 -- The following seems equivalent, but a bit dubious
3239 if Elaboration_Checks_Suppressed (Designator) then
3240 Set_Kill_Elaboration_Checks (Designator);
3243 if Scop /= Standard_Standard
3244 and then not Is_Child_Unit (Designator)
3246 Set_Categorization_From_Scope (Designator, Scop);
3248 -- For a compilation unit, check for library-unit pragmas
3250 Push_Scope (Designator);
3251 Set_Categorization_From_Pragmas (N);
3252 Validate_Categorization_Dependency (N, Designator);
3256 -- For a compilation unit, set body required. This flag will only be
3257 -- reset if a valid Import or Interface pragma is processed later on.
3259 if Nkind (Parent (N)) = N_Compilation_Unit then
3260 Set_Body_Required (Parent (N), True);
3262 if Ada_Version >= Ada_2005
3263 and then Nkind (Specification (N)) = N_Procedure_Specification
3264 and then Null_Present (Specification (N))
3267 ("null procedure cannot be declared at library level", N);
3271 Generate_Reference_To_Formals (Designator);
3272 Check_Eliminated (Designator);
3274 if Debug_Flag_C then
3276 Write_Str ("<== subprogram spec ");
3277 Write_Name (Chars (Designator));
3278 Write_Str (" from ");
3279 Write_Location (Sloc (N));
3283 if Is_Protected_Type (Current_Scope) then
3285 -- Indicate that this is a protected operation, because it may be
3286 -- used in subsequent declarations within the protected type.
3288 Set_Convention (Designator, Convention_Protected);
3291 List_Inherited_Pre_Post_Aspects (Designator);
3293 if Has_Aspects (N) then
3294 Analyze_Aspect_Specifications (N, Designator);
3296 end Analyze_Subprogram_Declaration;
3298 --------------------------------------
3299 -- Analyze_Subprogram_Specification --
3300 --------------------------------------
3302 -- Reminder: N here really is a subprogram specification (not a subprogram
3303 -- declaration). This procedure is called to analyze the specification in
3304 -- both subprogram bodies and subprogram declarations (specs).
3306 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
3307 Designator : constant Entity_Id := Defining_Entity (N);
3308 Formals : constant List_Id := Parameter_Specifications (N);
3310 -- Start of processing for Analyze_Subprogram_Specification
3313 -- User-defined operator is not allowed in SPARK, except as a renaming
3315 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
3316 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
3318 Check_SPARK_Restriction ("user-defined operator is not allowed", N);
3321 -- Proceed with analysis
3323 Generate_Definition (Designator);
3324 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
3326 if Nkind (N) = N_Function_Specification then
3327 Set_Ekind (Designator, E_Function);
3328 Set_Mechanism (Designator, Default_Mechanism);
3330 Set_Ekind (Designator, E_Procedure);
3331 Set_Etype (Designator, Standard_Void_Type);
3334 -- Introduce new scope for analysis of the formals and the return type
3336 Set_Scope (Designator, Current_Scope);
3338 if Present (Formals) then
3339 Push_Scope (Designator);
3340 Process_Formals (Formals, N);
3342 -- Ada 2005 (AI-345): If this is an overriding operation of an
3343 -- inherited interface operation, and the controlling type is
3344 -- a synchronized type, replace the type with its corresponding
3345 -- record, to match the proper signature of an overriding operation.
3346 -- Same processing for an access parameter whose designated type is
3347 -- derived from a synchronized interface.
3349 if Ada_Version >= Ada_2005 then
3352 Formal_Typ : Entity_Id;
3353 Rec_Typ : Entity_Id;
3354 Desig_Typ : Entity_Id;
3357 Formal := First_Formal (Designator);
3358 while Present (Formal) loop
3359 Formal_Typ := Etype (Formal);
3361 if Is_Concurrent_Type (Formal_Typ)
3362 and then Present (Corresponding_Record_Type (Formal_Typ))
3364 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
3366 if Present (Interfaces (Rec_Typ)) then
3367 Set_Etype (Formal, Rec_Typ);
3370 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
3371 Desig_Typ := Designated_Type (Formal_Typ);
3373 if Is_Concurrent_Type (Desig_Typ)
3374 and then Present (Corresponding_Record_Type (Desig_Typ))
3376 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
3378 if Present (Interfaces (Rec_Typ)) then
3379 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
3384 Next_Formal (Formal);
3391 -- The subprogram scope is pushed and popped around the processing of
3392 -- the return type for consistency with call above to Process_Formals
3393 -- (which itself can call Analyze_Return_Type), and to ensure that any
3394 -- itype created for the return type will be associated with the proper
3397 elsif Nkind (N) = N_Function_Specification then
3398 Push_Scope (Designator);
3399 Analyze_Return_Type (N);
3405 if Nkind (N) = N_Function_Specification then
3407 -- Deal with operator symbol case
3409 if Nkind (Designator) = N_Defining_Operator_Symbol then
3410 Valid_Operator_Definition (Designator);
3413 May_Need_Actuals (Designator);
3415 -- Ada 2005 (AI-251): If the return type is abstract, verify that
3416 -- the subprogram is abstract also. This does not apply to renaming
3417 -- declarations, where abstractness is inherited.
3419 -- In case of primitives associated with abstract interface types
3420 -- the check is applied later (see Analyze_Subprogram_Declaration).
3422 if not Nkind_In (Parent (N), N_Subprogram_Renaming_Declaration,
3423 N_Abstract_Subprogram_Declaration,
3424 N_Formal_Abstract_Subprogram_Declaration)
3426 if Is_Abstract_Type (Etype (Designator))
3427 and then not Is_Interface (Etype (Designator))
3430 ("function that returns abstract type must be abstract", N);
3432 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
3433 -- access result whose designated type is abstract.
3435 elsif Nkind (Result_Definition (N)) = N_Access_Definition
3437 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
3438 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
3439 and then Ada_Version >= Ada_2012
3441 Error_Msg_N ("function whose access result designates "
3442 & "abstract type must be abstract", N);
3448 end Analyze_Subprogram_Specification;
3450 --------------------------
3451 -- Build_Body_To_Inline --
3452 --------------------------
3454 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
3455 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
3456 Original_Body : Node_Id;
3457 Body_To_Analyze : Node_Id;
3458 Max_Size : constant := 10;
3459 Stat_Count : Integer := 0;
3461 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
3462 -- Check for declarations that make inlining not worthwhile
3464 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
3465 -- Check for statements that make inlining not worthwhile: any tasking
3466 -- statement, nested at any level. Keep track of total number of
3467 -- elementary statements, as a measure of acceptable size.
3469 function Has_Pending_Instantiation return Boolean;
3470 -- If some enclosing body contains instantiations that appear before the
3471 -- corresponding generic body, the enclosing body has a freeze node so
3472 -- that it can be elaborated after the generic itself. This might
3473 -- conflict with subsequent inlinings, so that it is unsafe to try to
3474 -- inline in such a case.
3476 function Has_Single_Return return Boolean;
3477 -- In general we cannot inline functions that return unconstrained type.
3478 -- However, we can handle such functions if all return statements return
3479 -- a local variable that is the only declaration in the body of the
3480 -- function. In that case the call can be replaced by that local
3481 -- variable as is done for other inlined calls.
3483 procedure Remove_Pragmas;
3484 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
3485 -- parameter has no meaning when the body is inlined and the formals
3486 -- are rewritten. Remove it from body to inline. The analysis of the
3487 -- non-inlined body will handle the pragma properly.
3489 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
3490 -- If the body of the subprogram includes a call that returns an
3491 -- unconstrained type, the secondary stack is involved, and it
3492 -- is not worth inlining.
3494 ------------------------------
3495 -- Has_Excluded_Declaration --
3496 ------------------------------
3498 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
3501 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
3502 -- Nested subprograms make a given body ineligible for inlining, but
3503 -- we make an exception for instantiations of unchecked conversion.
3504 -- The body has not been analyzed yet, so check the name, and verify
3505 -- that the visible entity with that name is the predefined unit.
3507 -----------------------------
3508 -- Is_Unchecked_Conversion --
3509 -----------------------------
3511 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
3512 Id : constant Node_Id := Name (D);
3516 if Nkind (Id) = N_Identifier
3517 and then Chars (Id) = Name_Unchecked_Conversion
3519 Conv := Current_Entity (Id);
3521 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
3522 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
3524 Conv := Current_Entity (Selector_Name (Id));
3529 return Present (Conv)
3530 and then Is_Predefined_File_Name
3531 (Unit_File_Name (Get_Source_Unit (Conv)))
3532 and then Is_Intrinsic_Subprogram (Conv);
3533 end Is_Unchecked_Conversion;
3535 -- Start of processing for Has_Excluded_Declaration
3539 while Present (D) loop
3540 if (Nkind (D) = N_Function_Instantiation
3541 and then not Is_Unchecked_Conversion (D))
3542 or else Nkind_In (D, N_Protected_Type_Declaration,
3543 N_Package_Declaration,
3544 N_Package_Instantiation,
3546 N_Procedure_Instantiation,
3547 N_Task_Type_Declaration)
3550 ("cannot inline & (non-allowed declaration)?", D, Subp);
3558 end Has_Excluded_Declaration;
3560 ----------------------------
3561 -- Has_Excluded_Statement --
3562 ----------------------------
3564 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
3570 while Present (S) loop
3571 Stat_Count := Stat_Count + 1;
3573 if Nkind_In (S, N_Abort_Statement,
3574 N_Asynchronous_Select,
3575 N_Conditional_Entry_Call,
3576 N_Delay_Relative_Statement,
3577 N_Delay_Until_Statement,
3582 ("cannot inline & (non-allowed statement)?", S, Subp);
3585 elsif Nkind (S) = N_Block_Statement then
3586 if Present (Declarations (S))
3587 and then Has_Excluded_Declaration (Declarations (S))
3591 elsif Present (Handled_Statement_Sequence (S))
3594 (Exception_Handlers (Handled_Statement_Sequence (S)))
3596 Has_Excluded_Statement
3597 (Statements (Handled_Statement_Sequence (S))))
3602 elsif Nkind (S) = N_Case_Statement then
3603 E := First (Alternatives (S));
3604 while Present (E) loop
3605 if Has_Excluded_Statement (Statements (E)) then
3612 elsif Nkind (S) = N_If_Statement then
3613 if Has_Excluded_Statement (Then_Statements (S)) then
3617 if Present (Elsif_Parts (S)) then
3618 E := First (Elsif_Parts (S));
3619 while Present (E) loop
3620 if Has_Excluded_Statement (Then_Statements (E)) then
3627 if Present (Else_Statements (S))
3628 and then Has_Excluded_Statement (Else_Statements (S))
3633 elsif Nkind (S) = N_Loop_Statement
3634 and then Has_Excluded_Statement (Statements (S))
3638 elsif Nkind (S) = N_Extended_Return_Statement then
3639 if Has_Excluded_Statement
3640 (Statements (Handled_Statement_Sequence (S)))
3642 (Exception_Handlers (Handled_Statement_Sequence (S)))
3652 end Has_Excluded_Statement;
3654 -------------------------------
3655 -- Has_Pending_Instantiation --
3656 -------------------------------
3658 function Has_Pending_Instantiation return Boolean is
3663 while Present (S) loop
3664 if Is_Compilation_Unit (S)
3665 or else Is_Child_Unit (S)
3669 elsif Ekind (S) = E_Package
3670 and then Has_Forward_Instantiation (S)
3679 end Has_Pending_Instantiation;
3681 ------------------------
3682 -- Has_Single_Return --
3683 ------------------------
3685 function Has_Single_Return return Boolean is
3686 Return_Statement : Node_Id := Empty;
3688 function Check_Return (N : Node_Id) return Traverse_Result;
3694 function Check_Return (N : Node_Id) return Traverse_Result is
3696 if Nkind (N) = N_Simple_Return_Statement then
3697 if Present (Expression (N))
3698 and then Is_Entity_Name (Expression (N))
3700 if No (Return_Statement) then
3701 Return_Statement := N;
3704 elsif Chars (Expression (N)) =
3705 Chars (Expression (Return_Statement))
3713 -- A return statement within an extended return is a noop
3716 elsif No (Expression (N))
3717 and then Nkind (Parent (Parent (N))) =
3718 N_Extended_Return_Statement
3723 -- Expression has wrong form
3728 -- We can only inline a build-in-place function if
3729 -- it has a single extended return.
3731 elsif Nkind (N) = N_Extended_Return_Statement then
3732 if No (Return_Statement) then
3733 Return_Statement := N;
3745 function Check_All_Returns is new Traverse_Func (Check_Return);
3747 -- Start of processing for Has_Single_Return
3750 if Check_All_Returns (N) /= OK then
3753 elsif Nkind (Return_Statement) = N_Extended_Return_Statement then
3757 return Present (Declarations (N))
3758 and then Present (First (Declarations (N)))
3759 and then Chars (Expression (Return_Statement)) =
3760 Chars (Defining_Identifier (First (Declarations (N))));
3762 end Has_Single_Return;
3764 --------------------
3765 -- Remove_Pragmas --
3766 --------------------
3768 procedure Remove_Pragmas is
3773 Decl := First (Declarations (Body_To_Analyze));
3774 while Present (Decl) loop
3777 if Nkind (Decl) = N_Pragma
3778 and then (Pragma_Name (Decl) = Name_Unreferenced
3780 Pragma_Name (Decl) = Name_Unmodified)
3789 --------------------------
3790 -- Uses_Secondary_Stack --
3791 --------------------------
3793 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3794 function Check_Call (N : Node_Id) return Traverse_Result;
3795 -- Look for function calls that return an unconstrained type
3801 function Check_Call (N : Node_Id) return Traverse_Result is
3803 if Nkind (N) = N_Function_Call
3804 and then Is_Entity_Name (Name (N))
3805 and then Is_Composite_Type (Etype (Entity (Name (N))))
3806 and then not Is_Constrained (Etype (Entity (Name (N))))
3809 ("cannot inline & (call returns unconstrained type)?",
3817 function Check_Calls is new Traverse_Func (Check_Call);
3820 return Check_Calls (Bod) = Abandon;
3821 end Uses_Secondary_Stack;
3823 -- Start of processing for Build_Body_To_Inline
3826 -- Return immediately if done already
3828 if Nkind (Decl) = N_Subprogram_Declaration
3829 and then Present (Body_To_Inline (Decl))
3833 -- Functions that return unconstrained composite types require
3834 -- secondary stack handling, and cannot currently be inlined, unless
3835 -- all return statements return a local variable that is the first
3836 -- local declaration in the body.
3838 elsif Ekind (Subp) = E_Function
3839 and then not Is_Scalar_Type (Etype (Subp))
3840 and then not Is_Access_Type (Etype (Subp))
3841 and then not Is_Constrained (Etype (Subp))
3843 if not Has_Single_Return then
3845 ("cannot inline & (unconstrained return type)?", N, Subp);
3849 -- Ditto for functions that return controlled types, where controlled
3850 -- actions interfere in complex ways with inlining.
3852 elsif Ekind (Subp) = E_Function
3853 and then Needs_Finalization (Etype (Subp))
3856 ("cannot inline & (controlled return type)?", N, Subp);
3860 if Present (Declarations (N))
3861 and then Has_Excluded_Declaration (Declarations (N))
3866 if Present (Handled_Statement_Sequence (N)) then
3867 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3869 ("cannot inline& (exception handler)?",
3870 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3874 Has_Excluded_Statement
3875 (Statements (Handled_Statement_Sequence (N)))
3881 -- We do not inline a subprogram that is too large, unless it is
3882 -- marked Inline_Always. This pragma does not suppress the other
3883 -- checks on inlining (forbidden declarations, handlers, etc).
3885 if Stat_Count > Max_Size
3886 and then not Has_Pragma_Inline_Always (Subp)
3888 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3892 if Has_Pending_Instantiation then
3894 ("cannot inline& (forward instance within enclosing body)?",
3899 -- Within an instance, the body to inline must be treated as a nested
3900 -- generic, so that the proper global references are preserved.
3902 -- Note that we do not do this at the library level, because it is not
3903 -- needed, and furthermore this causes trouble if front end inlining
3904 -- is activated (-gnatN).
3906 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3907 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3908 Original_Body := Copy_Generic_Node (N, Empty, True);
3910 Original_Body := Copy_Separate_Tree (N);
3913 -- We need to capture references to the formals in order to substitute
3914 -- the actuals at the point of inlining, i.e. instantiation. To treat
3915 -- the formals as globals to the body to inline, we nest it within
3916 -- a dummy parameterless subprogram, declared within the real one.
3917 -- To avoid generating an internal name (which is never public, and
3918 -- which affects serial numbers of other generated names), we use
3919 -- an internal symbol that cannot conflict with user declarations.
3921 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3922 Set_Defining_Unit_Name
3923 (Specification (Original_Body),
3924 Make_Defining_Identifier (Sloc (N), Name_uParent));
3925 Set_Corresponding_Spec (Original_Body, Empty);
3927 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3929 -- Set return type of function, which is also global and does not need
3932 if Ekind (Subp) = E_Function then
3933 Set_Result_Definition (Specification (Body_To_Analyze),
3934 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3937 if No (Declarations (N)) then
3938 Set_Declarations (N, New_List (Body_To_Analyze));
3940 Append (Body_To_Analyze, Declarations (N));
3943 Expander_Mode_Save_And_Set (False);
3946 Analyze (Body_To_Analyze);
3947 Push_Scope (Defining_Entity (Body_To_Analyze));
3948 Save_Global_References (Original_Body);
3950 Remove (Body_To_Analyze);
3952 Expander_Mode_Restore;
3954 -- Restore environment if previously saved
3956 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3960 -- If secondary stk used there is no point in inlining. We have
3961 -- already issued the warning in this case, so nothing to do.
3963 if Uses_Secondary_Stack (Body_To_Analyze) then
3967 Set_Body_To_Inline (Decl, Original_Body);
3968 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3969 Set_Is_Inlined (Subp);
3970 end Build_Body_To_Inline;
3976 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3978 -- Do not emit warning if this is a predefined unit which is not the
3979 -- main unit. With validity checks enabled, some predefined subprograms
3980 -- may contain nested subprograms and become ineligible for inlining.
3982 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3983 and then not In_Extended_Main_Source_Unit (Subp)
3987 elsif Has_Pragma_Inline_Always (Subp) then
3989 -- Remove last character (question mark) to make this into an error,
3990 -- because the Inline_Always pragma cannot be obeyed.
3992 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3994 elsif Ineffective_Inline_Warnings then
3995 Error_Msg_NE (Msg, N, Subp);
3999 -----------------------
4000 -- Check_Conformance --
4001 -----------------------
4003 procedure Check_Conformance
4004 (New_Id : Entity_Id;
4006 Ctype : Conformance_Type;
4008 Conforms : out Boolean;
4009 Err_Loc : Node_Id := Empty;
4010 Get_Inst : Boolean := False;
4011 Skip_Controlling_Formals : Boolean := False)
4013 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
4014 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
4015 -- If Errmsg is True, then processing continues to post an error message
4016 -- for conformance error on given node. Two messages are output. The
4017 -- first message points to the previous declaration with a general "no
4018 -- conformance" message. The second is the detailed reason, supplied as
4019 -- Msg. The parameter N provide information for a possible & insertion
4020 -- in the message, and also provides the location for posting the
4021 -- message in the absence of a specified Err_Loc location.
4023 -----------------------
4024 -- Conformance_Error --
4025 -----------------------
4027 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
4034 if No (Err_Loc) then
4040 Error_Msg_Sloc := Sloc (Old_Id);
4043 when Type_Conformant =>
4044 Error_Msg_N -- CODEFIX
4045 ("not type conformant with declaration#!", Enode);
4047 when Mode_Conformant =>
4048 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
4050 ("not mode conformant with operation inherited#!",
4054 ("not mode conformant with declaration#!", Enode);
4057 when Subtype_Conformant =>
4058 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
4060 ("not subtype conformant with operation inherited#!",
4064 ("not subtype conformant with declaration#!", Enode);
4067 when Fully_Conformant =>
4068 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
4069 Error_Msg_N -- CODEFIX
4070 ("not fully conformant with operation inherited#!",
4073 Error_Msg_N -- CODEFIX
4074 ("not fully conformant with declaration#!", Enode);
4078 Error_Msg_NE (Msg, Enode, N);
4080 end Conformance_Error;
4084 Old_Type : constant Entity_Id := Etype (Old_Id);
4085 New_Type : constant Entity_Id := Etype (New_Id);
4086 Old_Formal : Entity_Id;
4087 New_Formal : Entity_Id;
4088 Access_Types_Match : Boolean;
4089 Old_Formal_Base : Entity_Id;
4090 New_Formal_Base : Entity_Id;
4092 -- Start of processing for Check_Conformance
4097 -- We need a special case for operators, since they don't appear
4100 if Ctype = Type_Conformant then
4101 if Ekind (New_Id) = E_Operator
4102 and then Operator_Matches_Spec (New_Id, Old_Id)
4108 -- If both are functions/operators, check return types conform
4110 if Old_Type /= Standard_Void_Type
4111 and then New_Type /= Standard_Void_Type
4114 -- If we are checking interface conformance we omit controlling
4115 -- arguments and result, because we are only checking the conformance
4116 -- of the remaining parameters.
4118 if Has_Controlling_Result (Old_Id)
4119 and then Has_Controlling_Result (New_Id)
4120 and then Skip_Controlling_Formals
4124 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
4125 Conformance_Error ("\return type does not match!", New_Id);
4129 -- Ada 2005 (AI-231): In case of anonymous access types check the
4130 -- null-exclusion and access-to-constant attributes match.
4132 if Ada_Version >= Ada_2005
4133 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
4135 (Can_Never_Be_Null (Old_Type)
4136 /= Can_Never_Be_Null (New_Type)
4137 or else Is_Access_Constant (Etype (Old_Type))
4138 /= Is_Access_Constant (Etype (New_Type)))
4140 Conformance_Error ("\return type does not match!", New_Id);
4144 -- If either is a function/operator and the other isn't, error
4146 elsif Old_Type /= Standard_Void_Type
4147 or else New_Type /= Standard_Void_Type
4149 Conformance_Error ("\functions can only match functions!", New_Id);
4153 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
4154 -- If this is a renaming as body, refine error message to indicate that
4155 -- the conflict is with the original declaration. If the entity is not
4156 -- frozen, the conventions don't have to match, the one of the renamed
4157 -- entity is inherited.
4159 if Ctype >= Subtype_Conformant then
4160 if Convention (Old_Id) /= Convention (New_Id) then
4162 if not Is_Frozen (New_Id) then
4165 elsif Present (Err_Loc)
4166 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
4167 and then Present (Corresponding_Spec (Err_Loc))
4169 Error_Msg_Name_1 := Chars (New_Id);
4171 Name_Ada + Convention_Id'Pos (Convention (New_Id));
4172 Conformance_Error ("\prior declaration for% has convention %!");
4175 Conformance_Error ("\calling conventions do not match!");
4180 elsif Is_Formal_Subprogram (Old_Id)
4181 or else Is_Formal_Subprogram (New_Id)
4183 Conformance_Error ("\formal subprograms not allowed!");
4188 -- Deal with parameters
4190 -- Note: we use the entity information, rather than going directly
4191 -- to the specification in the tree. This is not only simpler, but
4192 -- absolutely necessary for some cases of conformance tests between
4193 -- operators, where the declaration tree simply does not exist!
4195 Old_Formal := First_Formal (Old_Id);
4196 New_Formal := First_Formal (New_Id);
4197 while Present (Old_Formal) and then Present (New_Formal) loop
4198 if Is_Controlling_Formal (Old_Formal)
4199 and then Is_Controlling_Formal (New_Formal)
4200 and then Skip_Controlling_Formals
4202 -- The controlling formals will have different types when
4203 -- comparing an interface operation with its match, but both
4204 -- or neither must be access parameters.
4206 if Is_Access_Type (Etype (Old_Formal))
4208 Is_Access_Type (Etype (New_Formal))
4210 goto Skip_Controlling_Formal;
4213 ("\access parameter does not match!", New_Formal);
4217 if Ctype = Fully_Conformant then
4219 -- Names must match. Error message is more accurate if we do
4220 -- this before checking that the types of the formals match.
4222 if Chars (Old_Formal) /= Chars (New_Formal) then
4223 Conformance_Error ("\name & does not match!", New_Formal);
4225 -- Set error posted flag on new formal as well to stop
4226 -- junk cascaded messages in some cases.
4228 Set_Error_Posted (New_Formal);
4232 -- Null exclusion must match
4234 if Null_Exclusion_Present (Parent (Old_Formal))
4236 Null_Exclusion_Present (Parent (New_Formal))
4238 -- Only give error if both come from source. This should be
4239 -- investigated some time, since it should not be needed ???
4241 if Comes_From_Source (Old_Formal)
4243 Comes_From_Source (New_Formal)
4246 ("\null exclusion for & does not match", New_Formal);
4248 -- Mark error posted on the new formal to avoid duplicated
4249 -- complaint about types not matching.
4251 Set_Error_Posted (New_Formal);
4256 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
4257 -- case occurs whenever a subprogram is being renamed and one of its
4258 -- parameters imposes a null exclusion. For example:
4260 -- type T is null record;
4261 -- type Acc_T is access T;
4262 -- subtype Acc_T_Sub is Acc_T;
4264 -- procedure P (Obj : not null Acc_T_Sub); -- itype
4265 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
4268 Old_Formal_Base := Etype (Old_Formal);
4269 New_Formal_Base := Etype (New_Formal);
4272 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
4273 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
4276 Access_Types_Match := Ada_Version >= Ada_2005
4278 -- Ensure that this rule is only applied when New_Id is a
4279 -- renaming of Old_Id.
4281 and then Nkind (Parent (Parent (New_Id))) =
4282 N_Subprogram_Renaming_Declaration
4283 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
4284 and then Present (Entity (Name (Parent (Parent (New_Id)))))
4285 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
4287 -- Now handle the allowed access-type case
4289 and then Is_Access_Type (Old_Formal_Base)
4290 and then Is_Access_Type (New_Formal_Base)
4292 -- The type kinds must match. The only exception occurs with
4293 -- multiple generics of the form:
4296 -- type F is private; type A is private;
4297 -- type F_Ptr is access F; type A_Ptr is access A;
4298 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
4299 -- package F_Pack is ... package A_Pack is
4300 -- package F_Inst is
4301 -- new F_Pack (A, A_Ptr, A_P);
4303 -- When checking for conformance between the parameters of A_P
4304 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
4305 -- because the compiler has transformed A_Ptr into a subtype of
4306 -- F_Ptr. We catch this case in the code below.
4308 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
4310 (Is_Generic_Type (Old_Formal_Base)
4311 and then Is_Generic_Type (New_Formal_Base)
4312 and then Is_Internal (New_Formal_Base)
4313 and then Etype (Etype (New_Formal_Base)) =
4315 and then Directly_Designated_Type (Old_Formal_Base) =
4316 Directly_Designated_Type (New_Formal_Base)
4317 and then ((Is_Itype (Old_Formal_Base)
4318 and then Can_Never_Be_Null (Old_Formal_Base))
4320 (Is_Itype (New_Formal_Base)
4321 and then Can_Never_Be_Null (New_Formal_Base)));
4323 -- Types must always match. In the visible part of an instance,
4324 -- usual overloading rules for dispatching operations apply, and
4325 -- we check base types (not the actual subtypes).
4327 if In_Instance_Visible_Part
4328 and then Is_Dispatching_Operation (New_Id)
4330 if not Conforming_Types
4331 (T1 => Base_Type (Etype (Old_Formal)),
4332 T2 => Base_Type (Etype (New_Formal)),
4334 Get_Inst => Get_Inst)
4335 and then not Access_Types_Match
4337 Conformance_Error ("\type of & does not match!", New_Formal);
4341 elsif not Conforming_Types
4342 (T1 => Old_Formal_Base,
4343 T2 => New_Formal_Base,
4345 Get_Inst => Get_Inst)
4346 and then not Access_Types_Match
4348 -- Don't give error message if old type is Any_Type. This test
4349 -- avoids some cascaded errors, e.g. in case of a bad spec.
4351 if Errmsg and then Old_Formal_Base = Any_Type then
4354 Conformance_Error ("\type of & does not match!", New_Formal);
4360 -- For mode conformance, mode must match
4362 if Ctype >= Mode_Conformant then
4363 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
4364 if not Ekind_In (New_Id, E_Function, E_Procedure)
4365 or else not Is_Primitive_Wrapper (New_Id)
4367 Conformance_Error ("\mode of & does not match!", New_Formal);
4371 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
4373 if Is_Protected_Type
4374 (Corresponding_Concurrent_Type (T))
4376 Error_Msg_PT (T, New_Id);
4379 ("\mode of & does not match!", New_Formal);
4386 -- Part of mode conformance for access types is having the same
4387 -- constant modifier.
4389 elsif Access_Types_Match
4390 and then Is_Access_Constant (Old_Formal_Base) /=
4391 Is_Access_Constant (New_Formal_Base)
4394 ("\constant modifier does not match!", New_Formal);
4399 if Ctype >= Subtype_Conformant then
4401 -- Ada 2005 (AI-231): In case of anonymous access types check
4402 -- the null-exclusion and access-to-constant attributes must
4403 -- match. For null exclusion, we test the types rather than the
4404 -- formals themselves, since the attribute is only set reliably
4405 -- on the formals in the Ada 95 case, and we exclude the case
4406 -- where Old_Formal is marked as controlling, to avoid errors
4407 -- when matching completing bodies with dispatching declarations
4408 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
4410 if Ada_Version >= Ada_2005
4411 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
4412 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
4414 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
4415 Can_Never_Be_Null (Etype (New_Formal))
4417 not Is_Controlling_Formal (Old_Formal))
4419 Is_Access_Constant (Etype (Old_Formal)) /=
4420 Is_Access_Constant (Etype (New_Formal)))
4422 -- Do not complain if error already posted on New_Formal. This
4423 -- avoids some redundant error messages.
4425 and then not Error_Posted (New_Formal)
4427 -- It is allowed to omit the null-exclusion in case of stream
4428 -- attribute subprograms. We recognize stream subprograms
4429 -- through their TSS-generated suffix.
4432 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
4434 if TSS_Name /= TSS_Stream_Read
4435 and then TSS_Name /= TSS_Stream_Write
4436 and then TSS_Name /= TSS_Stream_Input
4437 and then TSS_Name /= TSS_Stream_Output
4440 ("\type of & does not match!", New_Formal);
4447 -- Full conformance checks
4449 if Ctype = Fully_Conformant then
4451 -- We have checked already that names match
4453 if Parameter_Mode (Old_Formal) = E_In_Parameter then
4455 -- Check default expressions for in parameters
4458 NewD : constant Boolean :=
4459 Present (Default_Value (New_Formal));
4460 OldD : constant Boolean :=
4461 Present (Default_Value (Old_Formal));
4463 if NewD or OldD then
4465 -- The old default value has been analyzed because the
4466 -- current full declaration will have frozen everything
4467 -- before. The new default value has not been analyzed,
4468 -- so analyze it now before we check for conformance.
4471 Push_Scope (New_Id);
4472 Preanalyze_Spec_Expression
4473 (Default_Value (New_Formal), Etype (New_Formal));
4477 if not (NewD and OldD)
4478 or else not Fully_Conformant_Expressions
4479 (Default_Value (Old_Formal),
4480 Default_Value (New_Formal))
4483 ("\default expression for & does not match!",
4492 -- A couple of special checks for Ada 83 mode. These checks are
4493 -- skipped if either entity is an operator in package Standard,
4494 -- or if either old or new instance is not from the source program.
4496 if Ada_Version = Ada_83
4497 and then Sloc (Old_Id) > Standard_Location
4498 and then Sloc (New_Id) > Standard_Location
4499 and then Comes_From_Source (Old_Id)
4500 and then Comes_From_Source (New_Id)
4503 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
4504 New_Param : constant Node_Id := Declaration_Node (New_Formal);
4507 -- Explicit IN must be present or absent in both cases. This
4508 -- test is required only in the full conformance case.
4510 if In_Present (Old_Param) /= In_Present (New_Param)
4511 and then Ctype = Fully_Conformant
4514 ("\(Ada 83) IN must appear in both declarations",
4519 -- Grouping (use of comma in param lists) must be the same
4520 -- This is where we catch a misconformance like:
4523 -- A : Integer; B : Integer
4525 -- which are represented identically in the tree except
4526 -- for the setting of the flags More_Ids and Prev_Ids.
4528 if More_Ids (Old_Param) /= More_Ids (New_Param)
4529 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
4532 ("\grouping of & does not match!", New_Formal);
4538 -- This label is required when skipping controlling formals
4540 <<Skip_Controlling_Formal>>
4542 Next_Formal (Old_Formal);
4543 Next_Formal (New_Formal);
4546 if Present (Old_Formal) then
4547 Conformance_Error ("\too few parameters!");
4550 elsif Present (New_Formal) then
4551 Conformance_Error ("\too many parameters!", New_Formal);
4554 end Check_Conformance;
4556 -----------------------
4557 -- Check_Conventions --
4558 -----------------------
4560 procedure Check_Conventions (Typ : Entity_Id) is
4561 Ifaces_List : Elist_Id;
4563 procedure Check_Convention (Op : Entity_Id);
4564 -- Verify that the convention of inherited dispatching operation Op is
4565 -- consistent among all subprograms it overrides. In order to minimize
4566 -- the search, Search_From is utilized to designate a specific point in
4567 -- the list rather than iterating over the whole list once more.
4569 ----------------------
4570 -- Check_Convention --
4571 ----------------------
4573 procedure Check_Convention (Op : Entity_Id) is
4574 Iface_Elmt : Elmt_Id;
4575 Iface_Prim_Elmt : Elmt_Id;
4576 Iface_Prim : Entity_Id;
4579 Iface_Elmt := First_Elmt (Ifaces_List);
4580 while Present (Iface_Elmt) loop
4582 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
4583 while Present (Iface_Prim_Elmt) loop
4584 Iface_Prim := Node (Iface_Prim_Elmt);
4586 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
4587 and then Convention (Iface_Prim) /= Convention (Op)
4590 ("inconsistent conventions in primitive operations", Typ);
4592 Error_Msg_Name_1 := Chars (Op);
4593 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
4594 Error_Msg_Sloc := Sloc (Op);
4596 if Comes_From_Source (Op) or else No (Alias (Op)) then
4597 if not Present (Overridden_Operation (Op)) then
4598 Error_Msg_N ("\\primitive % defined #", Typ);
4601 ("\\overriding operation % with " &
4602 "convention % defined #", Typ);
4605 else pragma Assert (Present (Alias (Op)));
4606 Error_Msg_Sloc := Sloc (Alias (Op));
4608 ("\\inherited operation % with " &
4609 "convention % defined #", Typ);
4612 Error_Msg_Name_1 := Chars (Op);
4614 Get_Convention_Name (Convention (Iface_Prim));
4615 Error_Msg_Sloc := Sloc (Iface_Prim);
4617 ("\\overridden operation % with " &
4618 "convention % defined #", Typ);
4620 -- Avoid cascading errors
4625 Next_Elmt (Iface_Prim_Elmt);
4628 Next_Elmt (Iface_Elmt);
4630 end Check_Convention;
4634 Prim_Op : Entity_Id;
4635 Prim_Op_Elmt : Elmt_Id;
4637 -- Start of processing for Check_Conventions
4640 if not Has_Interfaces (Typ) then
4644 Collect_Interfaces (Typ, Ifaces_List);
4646 -- The algorithm checks every overriding dispatching operation against
4647 -- all the corresponding overridden dispatching operations, detecting
4648 -- differences in conventions.
4650 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
4651 while Present (Prim_Op_Elmt) loop
4652 Prim_Op := Node (Prim_Op_Elmt);
4654 -- A small optimization: skip the predefined dispatching operations
4655 -- since they always have the same convention.
4657 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
4658 Check_Convention (Prim_Op);
4661 Next_Elmt (Prim_Op_Elmt);
4663 end Check_Conventions;
4665 ------------------------------
4666 -- Check_Delayed_Subprogram --
4667 ------------------------------
4669 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
4672 procedure Possible_Freeze (T : Entity_Id);
4673 -- T is the type of either a formal parameter or of the return type.
4674 -- If T is not yet frozen and needs a delayed freeze, then the
4675 -- subprogram itself must be delayed. If T is the limited view of an
4676 -- incomplete type the subprogram must be frozen as well, because
4677 -- T may depend on local types that have not been frozen yet.
4679 ---------------------
4680 -- Possible_Freeze --
4681 ---------------------
4683 procedure Possible_Freeze (T : Entity_Id) is
4685 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
4686 Set_Has_Delayed_Freeze (Designator);
4688 elsif Is_Access_Type (T)
4689 and then Has_Delayed_Freeze (Designated_Type (T))
4690 and then not Is_Frozen (Designated_Type (T))
4692 Set_Has_Delayed_Freeze (Designator);
4694 elsif Ekind (T) = E_Incomplete_Type and then From_With_Type (T) then
4695 Set_Has_Delayed_Freeze (Designator);
4697 -- AI05-0151: In Ada 2012, Incomplete types can appear in the profile
4698 -- of a subprogram or entry declaration.
4700 elsif Ekind (T) = E_Incomplete_Type
4701 and then Ada_Version >= Ada_2012
4703 Set_Has_Delayed_Freeze (Designator);
4706 end Possible_Freeze;
4708 -- Start of processing for Check_Delayed_Subprogram
4711 -- All subprograms, including abstract subprograms, may need a freeze
4712 -- node if some formal type or the return type needs one.
4714 Possible_Freeze (Etype (Designator));
4715 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
4717 -- Need delayed freeze if any of the formal types themselves need
4718 -- a delayed freeze and are not yet frozen.
4720 F := First_Formal (Designator);
4721 while Present (F) loop
4722 Possible_Freeze (Etype (F));
4723 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
4727 -- Mark functions that return by reference. Note that it cannot be
4728 -- done for delayed_freeze subprograms because the underlying
4729 -- returned type may not be known yet (for private types)
4731 if not Has_Delayed_Freeze (Designator)
4732 and then Expander_Active
4735 Typ : constant Entity_Id := Etype (Designator);
4736 Utyp : constant Entity_Id := Underlying_Type (Typ);
4739 if Is_Immutably_Limited_Type (Typ) then
4740 Set_Returns_By_Ref (Designator);
4742 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
4743 Set_Returns_By_Ref (Designator);
4747 end Check_Delayed_Subprogram;
4749 ------------------------------------
4750 -- Check_Discriminant_Conformance --
4751 ------------------------------------
4753 procedure Check_Discriminant_Conformance
4758 Old_Discr : Entity_Id := First_Discriminant (Prev);
4759 New_Discr : Node_Id := First (Discriminant_Specifications (N));
4760 New_Discr_Id : Entity_Id;
4761 New_Discr_Type : Entity_Id;
4763 procedure Conformance_Error (Msg : String; N : Node_Id);
4764 -- Post error message for conformance error on given node. Two messages
4765 -- are output. The first points to the previous declaration with a
4766 -- general "no conformance" message. The second is the detailed reason,
4767 -- supplied as Msg. The parameter N provide information for a possible
4768 -- & insertion in the message.
4770 -----------------------
4771 -- Conformance_Error --
4772 -----------------------
4774 procedure Conformance_Error (Msg : String; N : Node_Id) is
4776 Error_Msg_Sloc := Sloc (Prev_Loc);
4777 Error_Msg_N -- CODEFIX
4778 ("not fully conformant with declaration#!", N);
4779 Error_Msg_NE (Msg, N, N);
4780 end Conformance_Error;
4782 -- Start of processing for Check_Discriminant_Conformance
4785 while Present (Old_Discr) and then Present (New_Discr) loop
4787 New_Discr_Id := Defining_Identifier (New_Discr);
4789 -- The subtype mark of the discriminant on the full type has not
4790 -- been analyzed so we do it here. For an access discriminant a new
4793 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
4795 Access_Definition (N, Discriminant_Type (New_Discr));
4798 Analyze (Discriminant_Type (New_Discr));
4799 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
4801 -- Ada 2005: if the discriminant definition carries a null
4802 -- exclusion, create an itype to check properly for consistency
4803 -- with partial declaration.
4805 if Is_Access_Type (New_Discr_Type)
4806 and then Null_Exclusion_Present (New_Discr)
4809 Create_Null_Excluding_Itype
4810 (T => New_Discr_Type,
4811 Related_Nod => New_Discr,
4812 Scope_Id => Current_Scope);
4816 if not Conforming_Types
4817 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
4819 Conformance_Error ("type of & does not match!", New_Discr_Id);
4822 -- Treat the new discriminant as an occurrence of the old one,
4823 -- for navigation purposes, and fill in some semantic
4824 -- information, for completeness.
4826 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
4827 Set_Etype (New_Discr_Id, Etype (Old_Discr));
4828 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4833 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4834 Conformance_Error ("name & does not match!", New_Discr_Id);
4838 -- Default expressions must match
4841 NewD : constant Boolean :=
4842 Present (Expression (New_Discr));
4843 OldD : constant Boolean :=
4844 Present (Expression (Parent (Old_Discr)));
4847 if NewD or OldD then
4849 -- The old default value has been analyzed and expanded,
4850 -- because the current full declaration will have frozen
4851 -- everything before. The new default values have not been
4852 -- expanded, so expand now to check conformance.
4855 Preanalyze_Spec_Expression
4856 (Expression (New_Discr), New_Discr_Type);
4859 if not (NewD and OldD)
4860 or else not Fully_Conformant_Expressions
4861 (Expression (Parent (Old_Discr)),
4862 Expression (New_Discr))
4866 ("default expression for & does not match!",
4873 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4875 if Ada_Version = Ada_83 then
4877 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4880 -- Grouping (use of comma in param lists) must be the same
4881 -- This is where we catch a misconformance like:
4884 -- A : Integer; B : Integer
4886 -- which are represented identically in the tree except
4887 -- for the setting of the flags More_Ids and Prev_Ids.
4889 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4890 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4893 ("grouping of & does not match!", New_Discr_Id);
4899 Next_Discriminant (Old_Discr);
4903 if Present (Old_Discr) then
4904 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4907 elsif Present (New_Discr) then
4909 ("too many discriminants!", Defining_Identifier (New_Discr));
4912 end Check_Discriminant_Conformance;
4914 ----------------------------
4915 -- Check_Fully_Conformant --
4916 ----------------------------
4918 procedure Check_Fully_Conformant
4919 (New_Id : Entity_Id;
4921 Err_Loc : Node_Id := Empty)
4924 pragma Warnings (Off, Result);
4927 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4928 end Check_Fully_Conformant;
4930 ---------------------------
4931 -- Check_Mode_Conformant --
4932 ---------------------------
4934 procedure Check_Mode_Conformant
4935 (New_Id : Entity_Id;
4937 Err_Loc : Node_Id := Empty;
4938 Get_Inst : Boolean := False)
4941 pragma Warnings (Off, Result);
4944 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4945 end Check_Mode_Conformant;
4947 --------------------------------
4948 -- Check_Overriding_Indicator --
4949 --------------------------------
4951 procedure Check_Overriding_Indicator
4953 Overridden_Subp : Entity_Id;
4954 Is_Primitive : Boolean)
4960 -- No overriding indicator for literals
4962 if Ekind (Subp) = E_Enumeration_Literal then
4965 elsif Ekind (Subp) = E_Entry then
4966 Decl := Parent (Subp);
4968 -- No point in analyzing a malformed operator
4970 elsif Nkind (Subp) = N_Defining_Operator_Symbol
4971 and then Error_Posted (Subp)
4976 Decl := Unit_Declaration_Node (Subp);
4979 if Nkind_In (Decl, N_Subprogram_Body,
4980 N_Subprogram_Body_Stub,
4981 N_Subprogram_Declaration,
4982 N_Abstract_Subprogram_Declaration,
4983 N_Subprogram_Renaming_Declaration)
4985 Spec := Specification (Decl);
4987 elsif Nkind (Decl) = N_Entry_Declaration then
4994 -- The overriding operation is type conformant with the overridden one,
4995 -- but the names of the formals are not required to match. If the names
4996 -- appear permuted in the overriding operation, this is a possible
4997 -- source of confusion that is worth diagnosing. Controlling formals
4998 -- often carry names that reflect the type, and it is not worthwhile
4999 -- requiring that their names match.
5001 if Present (Overridden_Subp)
5002 and then Nkind (Subp) /= N_Defining_Operator_Symbol
5009 Form1 := First_Formal (Subp);
5010 Form2 := First_Formal (Overridden_Subp);
5012 -- If the overriding operation is a synchronized operation, skip
5013 -- the first parameter of the overridden operation, which is
5014 -- implicit in the new one. If the operation is declared in the
5015 -- body it is not primitive and all formals must match.
5017 if Is_Concurrent_Type (Scope (Subp))
5018 and then Is_Tagged_Type (Scope (Subp))
5019 and then not Has_Completion (Scope (Subp))
5021 Form2 := Next_Formal (Form2);
5024 if Present (Form1) then
5025 Form1 := Next_Formal (Form1);
5026 Form2 := Next_Formal (Form2);
5029 while Present (Form1) loop
5030 if not Is_Controlling_Formal (Form1)
5031 and then Present (Next_Formal (Form2))
5032 and then Chars (Form1) = Chars (Next_Formal (Form2))
5034 Error_Msg_Node_2 := Alias (Overridden_Subp);
5035 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
5037 ("& does not match corresponding formal of&#",
5042 Next_Formal (Form1);
5043 Next_Formal (Form2);
5048 -- If there is an overridden subprogram, then check that there is no
5049 -- "not overriding" indicator, and mark the subprogram as overriding.
5050 -- This is not done if the overridden subprogram is marked as hidden,
5051 -- which can occur for the case of inherited controlled operations
5052 -- (see Derive_Subprogram), unless the inherited subprogram's parent
5053 -- subprogram is not itself hidden. (Note: This condition could probably
5054 -- be simplified, leaving out the testing for the specific controlled
5055 -- cases, but it seems safer and clearer this way, and echoes similar
5056 -- special-case tests of this kind in other places.)
5058 if Present (Overridden_Subp)
5059 and then (not Is_Hidden (Overridden_Subp)
5061 ((Chars (Overridden_Subp) = Name_Initialize
5063 Chars (Overridden_Subp) = Name_Adjust
5065 Chars (Overridden_Subp) = Name_Finalize)
5066 and then Present (Alias (Overridden_Subp))
5067 and then not Is_Hidden (Alias (Overridden_Subp))))
5069 if Must_Not_Override (Spec) then
5070 Error_Msg_Sloc := Sloc (Overridden_Subp);
5072 if Ekind (Subp) = E_Entry then
5074 ("entry & overrides inherited operation #", Spec, Subp);
5077 ("subprogram & overrides inherited operation #", Spec, Subp);
5080 -- Special-case to fix a GNAT oddity: Limited_Controlled is declared
5081 -- as an extension of Root_Controlled, and thus has a useless Adjust
5082 -- operation. This operation should not be inherited by other limited
5083 -- controlled types. An explicit Adjust for them is not overriding.
5085 elsif Must_Override (Spec)
5086 and then Chars (Overridden_Subp) = Name_Adjust
5087 and then Is_Limited_Type (Etype (First_Formal (Subp)))
5088 and then Present (Alias (Overridden_Subp))
5090 Is_Predefined_File_Name
5091 (Unit_File_Name (Get_Source_Unit (Alias (Overridden_Subp))))
5093 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5095 elsif Is_Subprogram (Subp) then
5096 if Is_Init_Proc (Subp) then
5099 elsif No (Overridden_Operation (Subp)) then
5101 -- For entities generated by Derive_Subprograms the overridden
5102 -- operation is the inherited primitive (which is available
5103 -- through the attribute alias)
5105 if (Is_Dispatching_Operation (Subp)
5106 or else Is_Dispatching_Operation (Overridden_Subp))
5107 and then not Comes_From_Source (Overridden_Subp)
5108 and then Find_Dispatching_Type (Overridden_Subp) =
5109 Find_Dispatching_Type (Subp)
5110 and then Present (Alias (Overridden_Subp))
5111 and then Comes_From_Source (Alias (Overridden_Subp))
5113 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
5116 Set_Overridden_Operation (Subp, Overridden_Subp);
5121 -- If primitive flag is set or this is a protected operation, then
5122 -- the operation is overriding at the point of its declaration, so
5123 -- warn if necessary. Otherwise it may have been declared before the
5124 -- operation it overrides and no check is required.
5127 and then not Must_Override (Spec)
5128 and then (Is_Primitive
5129 or else Ekind (Scope (Subp)) = E_Protected_Type)
5131 Style.Missing_Overriding (Decl, Subp);
5134 -- If Subp is an operator, it may override a predefined operation, if
5135 -- it is defined in the same scope as the type to which it applies.
5136 -- In that case Overridden_Subp is empty because of our implicit
5137 -- representation for predefined operators. We have to check whether the
5138 -- signature of Subp matches that of a predefined operator. Note that
5139 -- first argument provides the name of the operator, and the second
5140 -- argument the signature that may match that of a standard operation.
5141 -- If the indicator is overriding, then the operator must match a
5142 -- predefined signature, because we know already that there is no
5143 -- explicit overridden operation.
5145 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
5146 if Must_Not_Override (Spec) then
5148 -- If this is not a primitive or a protected subprogram, then
5149 -- "not overriding" is illegal.
5152 and then Ekind (Scope (Subp)) /= E_Protected_Type
5155 ("overriding indicator only allowed "
5156 & "if subprogram is primitive", Subp);
5158 elsif Can_Override_Operator (Subp) then
5160 ("subprogram& overrides predefined operator ", Spec, Subp);
5163 elsif Must_Override (Spec) then
5164 if No (Overridden_Operation (Subp))
5165 and then not Can_Override_Operator (Subp)
5167 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5170 elsif not Error_Posted (Subp)
5171 and then Style_Check
5172 and then Can_Override_Operator (Subp)
5174 not Is_Predefined_File_Name
5175 (Unit_File_Name (Get_Source_Unit (Subp)))
5177 -- If style checks are enabled, indicate that the indicator is
5178 -- missing. However, at the point of declaration, the type of
5179 -- which this is a primitive operation may be private, in which
5180 -- case the indicator would be premature.
5182 if Has_Private_Declaration (Etype (Subp))
5183 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
5187 Style.Missing_Overriding (Decl, Subp);
5191 elsif Must_Override (Spec) then
5192 if Ekind (Subp) = E_Entry then
5193 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
5195 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5198 -- If the operation is marked "not overriding" and it's not primitive
5199 -- then an error is issued, unless this is an operation of a task or
5200 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
5201 -- has been specified have already been checked above.
5203 elsif Must_Not_Override (Spec)
5204 and then not Is_Primitive
5205 and then Ekind (Subp) /= E_Entry
5206 and then Ekind (Scope (Subp)) /= E_Protected_Type
5209 ("overriding indicator only allowed if subprogram is primitive",
5213 end Check_Overriding_Indicator;
5219 -- Note: this procedure needs to know far too much about how the expander
5220 -- messes with exceptions. The use of the flag Exception_Junk and the
5221 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
5222 -- works, but is not very clean. It would be better if the expansion
5223 -- routines would leave Original_Node working nicely, and we could use
5224 -- Original_Node here to ignore all the peculiar expander messing ???
5226 procedure Check_Returns
5230 Proc : Entity_Id := Empty)
5234 procedure Check_Statement_Sequence (L : List_Id);
5235 -- Internal recursive procedure to check a list of statements for proper
5236 -- termination by a return statement (or a transfer of control or a
5237 -- compound statement that is itself internally properly terminated).
5239 ------------------------------
5240 -- Check_Statement_Sequence --
5241 ------------------------------
5243 procedure Check_Statement_Sequence (L : List_Id) is
5248 Raise_Exception_Call : Boolean;
5249 -- Set True if statement sequence terminated by Raise_Exception call
5250 -- or a Reraise_Occurrence call.
5253 Raise_Exception_Call := False;
5255 -- Get last real statement
5257 Last_Stm := Last (L);
5259 -- Deal with digging out exception handler statement sequences that
5260 -- have been transformed by the local raise to goto optimization.
5261 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
5262 -- optimization has occurred, we are looking at something like:
5265 -- original stmts in block
5269 -- goto L1; | omitted if No_Exception_Propagation
5274 -- goto L3; -- skip handler when exception not raised
5276 -- <<L1>> -- target label for local exception
5290 -- and what we have to do is to dig out the estmts1 and estmts2
5291 -- sequences (which were the original sequences of statements in
5292 -- the exception handlers) and check them.
5294 if Nkind (Last_Stm) = N_Label
5295 and then Exception_Junk (Last_Stm)
5301 exit when Nkind (Stm) /= N_Block_Statement;
5302 exit when not Exception_Junk (Stm);
5305 exit when Nkind (Stm) /= N_Label;
5306 exit when not Exception_Junk (Stm);
5307 Check_Statement_Sequence
5308 (Statements (Handled_Statement_Sequence (Next (Stm))));
5313 exit when Nkind (Stm) /= N_Goto_Statement;
5314 exit when not Exception_Junk (Stm);
5318 -- Don't count pragmas
5320 while Nkind (Last_Stm) = N_Pragma
5322 -- Don't count call to SS_Release (can happen after Raise_Exception)
5325 (Nkind (Last_Stm) = N_Procedure_Call_Statement
5327 Nkind (Name (Last_Stm)) = N_Identifier
5329 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
5331 -- Don't count exception junk
5334 (Nkind_In (Last_Stm, N_Goto_Statement,
5336 N_Object_Declaration)
5337 and then Exception_Junk (Last_Stm))
5338 or else Nkind (Last_Stm) in N_Push_xxx_Label
5339 or else Nkind (Last_Stm) in N_Pop_xxx_Label
5344 -- Here we have the "real" last statement
5346 Kind := Nkind (Last_Stm);
5348 -- Transfer of control, OK. Note that in the No_Return procedure
5349 -- case, we already diagnosed any explicit return statements, so
5350 -- we can treat them as OK in this context.
5352 if Is_Transfer (Last_Stm) then
5355 -- Check cases of explicit non-indirect procedure calls
5357 elsif Kind = N_Procedure_Call_Statement
5358 and then Is_Entity_Name (Name (Last_Stm))
5360 -- Check call to Raise_Exception procedure which is treated
5361 -- specially, as is a call to Reraise_Occurrence.
5363 -- We suppress the warning in these cases since it is likely that
5364 -- the programmer really does not expect to deal with the case
5365 -- of Null_Occurrence, and thus would find a warning about a
5366 -- missing return curious, and raising Program_Error does not
5367 -- seem such a bad behavior if this does occur.
5369 -- Note that in the Ada 2005 case for Raise_Exception, the actual
5370 -- behavior will be to raise Constraint_Error (see AI-329).
5372 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
5374 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
5376 Raise_Exception_Call := True;
5378 -- For Raise_Exception call, test first argument, if it is
5379 -- an attribute reference for a 'Identity call, then we know
5380 -- that the call cannot possibly return.
5383 Arg : constant Node_Id :=
5384 Original_Node (First_Actual (Last_Stm));
5386 if Nkind (Arg) = N_Attribute_Reference
5387 and then Attribute_Name (Arg) = Name_Identity
5394 -- If statement, need to look inside if there is an else and check
5395 -- each constituent statement sequence for proper termination.
5397 elsif Kind = N_If_Statement
5398 and then Present (Else_Statements (Last_Stm))
5400 Check_Statement_Sequence (Then_Statements (Last_Stm));
5401 Check_Statement_Sequence (Else_Statements (Last_Stm));
5403 if Present (Elsif_Parts (Last_Stm)) then
5405 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
5408 while Present (Elsif_Part) loop
5409 Check_Statement_Sequence (Then_Statements (Elsif_Part));
5417 -- Case statement, check each case for proper termination
5419 elsif Kind = N_Case_Statement then
5423 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
5424 while Present (Case_Alt) loop
5425 Check_Statement_Sequence (Statements (Case_Alt));
5426 Next_Non_Pragma (Case_Alt);
5432 -- Block statement, check its handled sequence of statements
5434 elsif Kind = N_Block_Statement then
5440 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
5449 -- Loop statement. If there is an iteration scheme, we can definitely
5450 -- fall out of the loop. Similarly if there is an exit statement, we
5451 -- can fall out. In either case we need a following return.
5453 elsif Kind = N_Loop_Statement then
5454 if Present (Iteration_Scheme (Last_Stm))
5455 or else Has_Exit (Entity (Identifier (Last_Stm)))
5459 -- A loop with no exit statement or iteration scheme is either
5460 -- an infinite loop, or it has some other exit (raise/return).
5461 -- In either case, no warning is required.
5467 -- Timed entry call, check entry call and delay alternatives
5469 -- Note: in expanded code, the timed entry call has been converted
5470 -- to a set of expanded statements on which the check will work
5471 -- correctly in any case.
5473 elsif Kind = N_Timed_Entry_Call then
5475 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5476 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
5479 -- If statement sequence of entry call alternative is missing,
5480 -- then we can definitely fall through, and we post the error
5481 -- message on the entry call alternative itself.
5483 if No (Statements (ECA)) then
5486 -- If statement sequence of delay alternative is missing, then
5487 -- we can definitely fall through, and we post the error
5488 -- message on the delay alternative itself.
5490 -- Note: if both ECA and DCA are missing the return, then we
5491 -- post only one message, should be enough to fix the bugs.
5492 -- If not we will get a message next time on the DCA when the
5495 elsif No (Statements (DCA)) then
5498 -- Else check both statement sequences
5501 Check_Statement_Sequence (Statements (ECA));
5502 Check_Statement_Sequence (Statements (DCA));
5507 -- Conditional entry call, check entry call and else part
5509 -- Note: in expanded code, the conditional entry call has been
5510 -- converted to a set of expanded statements on which the check
5511 -- will work correctly in any case.
5513 elsif Kind = N_Conditional_Entry_Call then
5515 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5518 -- If statement sequence of entry call alternative is missing,
5519 -- then we can definitely fall through, and we post the error
5520 -- message on the entry call alternative itself.
5522 if No (Statements (ECA)) then
5525 -- Else check statement sequence and else part
5528 Check_Statement_Sequence (Statements (ECA));
5529 Check_Statement_Sequence (Else_Statements (Last_Stm));
5535 -- If we fall through, issue appropriate message
5538 if not Raise_Exception_Call then
5540 ("?RETURN statement missing following this statement!",
5543 ("\?Program_Error may be raised at run time!",
5547 -- Note: we set Err even though we have not issued a warning
5548 -- because we still have a case of a missing return. This is
5549 -- an extremely marginal case, probably will never be noticed
5550 -- but we might as well get it right.
5554 -- Otherwise we have the case of a procedure marked No_Return
5557 if not Raise_Exception_Call then
5559 ("?implied return after this statement " &
5560 "will raise Program_Error",
5563 ("\?procedure & is marked as No_Return!",
5568 RE : constant Node_Id :=
5569 Make_Raise_Program_Error (Sloc (Last_Stm),
5570 Reason => PE_Implicit_Return);
5572 Insert_After (Last_Stm, RE);
5576 end Check_Statement_Sequence;
5578 -- Start of processing for Check_Returns
5582 Check_Statement_Sequence (Statements (HSS));
5584 if Present (Exception_Handlers (HSS)) then
5585 Handler := First_Non_Pragma (Exception_Handlers (HSS));
5586 while Present (Handler) loop
5587 Check_Statement_Sequence (Statements (Handler));
5588 Next_Non_Pragma (Handler);
5593 -------------------------------
5594 -- Check_Subprogram_Contract --
5595 -------------------------------
5597 procedure Check_Subprogram_Contract (Spec_Id : Entity_Id) is
5599 -- Code is currently commented out as, in some cases, it causes crashes
5600 -- because Direct_Primitive_Operations is not available for a private
5601 -- type. This may cause more warnings to be issued than necessary. See
5602 -- below for the intended use of this variable. ???
5604 -- Inherited : constant Subprogram_List :=
5605 -- Inherited_Subprograms (Spec_Id);
5606 -- -- List of subprograms inherited by this subprogram
5608 Last_Postcondition : Node_Id := Empty;
5609 -- Last postcondition on the subprogram, or else Empty if either no
5610 -- postcondition or only inherited postconditions.
5612 Attribute_Result_Mentioned : Boolean := False;
5613 -- Whether attribute 'Result is mentioned in a postcondition
5615 Post_State_Mentioned : Boolean := False;
5616 -- Whether some expression mentioned in a postcondition can have a
5617 -- different value in the post-state than in the pre-state.
5619 function Check_Attr_Result (N : Node_Id) return Traverse_Result;
5620 -- Check if N is a reference to the attribute 'Result, and if so set
5621 -- Attribute_Result_Mentioned and return Abandon. Otherwise return OK.
5623 function Check_Post_State (N : Node_Id) return Traverse_Result;
5624 -- Check whether the value of evaluating N can be different in the
5625 -- post-state, compared to the same evaluation in the pre-state, and
5626 -- if so set Post_State_Mentioned and return Abandon. Return Skip on
5627 -- reference to attribute 'Old, in order to ignore its prefix, which
5628 -- is precisely evaluated in the pre-state. Otherwise return OK.
5630 procedure Process_Post_Conditions (Spec : Node_Id; Class : Boolean);
5631 -- This processes the Spec_PPC_List from Spec, processing any
5632 -- postconditions from the list. If Class is True, then only
5633 -- postconditions marked with Class_Present are considered. The
5634 -- caller has checked that Spec_PPC_List is non-Empty.
5636 function Find_Attribute_Result is new Traverse_Func (Check_Attr_Result);
5638 function Find_Post_State is new Traverse_Func (Check_Post_State);
5640 -----------------------
5641 -- Check_Attr_Result --
5642 -----------------------
5644 function Check_Attr_Result (N : Node_Id) return Traverse_Result is
5646 if Nkind (N) = N_Attribute_Reference
5647 and then Get_Attribute_Id (Attribute_Name (N)) = Attribute_Result
5649 Attribute_Result_Mentioned := True;
5654 end Check_Attr_Result;
5656 ----------------------
5657 -- Check_Post_State --
5658 ----------------------
5660 function Check_Post_State (N : Node_Id) return Traverse_Result is
5661 Found : Boolean := False;
5665 when N_Function_Call |
5666 N_Explicit_Dereference =>
5673 E : constant Entity_Id := Entity (N);
5676 -- ???Quantified expressions get analyzed later, so E can
5677 -- be empty at this point. In this case, we suppress the
5678 -- warning, just in case E is assignable. It seems better to
5679 -- have false negatives than false positives. At some point,
5680 -- we should make the warning more accurate, either by
5681 -- analyzing quantified expressions earlier, or moving
5682 -- this processing later.
5687 and then Ekind (E) in Assignable_Kind)
5693 when N_Attribute_Reference =>
5694 case Get_Attribute_Id (Attribute_Name (N)) is
5695 when Attribute_Old =>
5697 when Attribute_Result =>
5708 Post_State_Mentioned := True;
5713 end Check_Post_State;
5715 -----------------------------
5716 -- Process_Post_Conditions --
5717 -----------------------------
5719 procedure Process_Post_Conditions
5725 Ignored : Traverse_Final_Result;
5726 pragma Unreferenced (Ignored);
5729 Prag := Spec_PPC_List (Contract (Spec));
5732 Arg := First (Pragma_Argument_Associations (Prag));
5734 -- Since pre- and post-conditions are listed in reverse order, the
5735 -- first postcondition in the list is the last in the source.
5737 if Pragma_Name (Prag) = Name_Postcondition
5739 and then No (Last_Postcondition)
5741 Last_Postcondition := Prag;
5744 -- For functions, look for presence of 'Result in postcondition
5746 if Ekind_In (Spec_Id, E_Function, E_Generic_Function) then
5747 Ignored := Find_Attribute_Result (Arg);
5750 -- For each individual non-inherited postcondition, look for
5751 -- presence of an expression that could be evaluated differently
5754 if Pragma_Name (Prag) = Name_Postcondition
5757 Post_State_Mentioned := False;
5758 Ignored := Find_Post_State (Arg);
5760 if not Post_State_Mentioned then
5761 Error_Msg_N ("?postcondition refers only to pre-state",
5766 Prag := Next_Pragma (Prag);
5767 exit when No (Prag);
5769 end Process_Post_Conditions;
5771 -- Start of processing for Check_Subprogram_Contract
5774 if not Warn_On_Suspicious_Contract then
5778 if Present (Spec_PPC_List (Contract (Spec_Id))) then
5779 Process_Post_Conditions (Spec_Id, Class => False);
5782 -- Process inherited postconditions
5784 -- Code is currently commented out as, in some cases, it causes crashes
5785 -- because Direct_Primitive_Operations is not available for a private
5786 -- type. This may cause more warnings to be issued than necessary. ???
5788 -- for J in Inherited'Range loop
5789 -- if Present (Spec_PPC_List (Contract (Inherited (J)))) then
5790 -- Process_Post_Conditions (Inherited (J), Class => True);
5794 -- Issue warning for functions whose postcondition does not mention
5795 -- 'Result after all postconditions have been processed.
5797 if Ekind_In (Spec_Id, E_Function, E_Generic_Function)
5798 and then Present (Last_Postcondition)
5799 and then not Attribute_Result_Mentioned
5801 Error_Msg_N ("?function postcondition does not mention result",
5802 Last_Postcondition);
5804 end Check_Subprogram_Contract;
5806 ----------------------------
5807 -- Check_Subprogram_Order --
5808 ----------------------------
5810 procedure Check_Subprogram_Order (N : Node_Id) is
5812 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
5813 -- This is used to check if S1 > S2 in the sense required by this test,
5814 -- for example nameab < namec, but name2 < name10.
5816 -----------------------------
5817 -- Subprogram_Name_Greater --
5818 -----------------------------
5820 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
5825 -- Remove trailing numeric parts
5828 while S1 (L1) in '0' .. '9' loop
5833 while S2 (L2) in '0' .. '9' loop
5837 -- If non-numeric parts non-equal, that's decisive
5839 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
5842 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
5845 -- If non-numeric parts equal, compare suffixed numeric parts. Note
5846 -- that a missing suffix is treated as numeric zero in this test.
5850 while L1 < S1'Last loop
5852 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
5856 while L2 < S2'Last loop
5858 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
5863 end Subprogram_Name_Greater;
5865 -- Start of processing for Check_Subprogram_Order
5868 -- Check body in alpha order if this is option
5871 and then Style_Check_Order_Subprograms
5872 and then Nkind (N) = N_Subprogram_Body
5873 and then Comes_From_Source (N)
5874 and then In_Extended_Main_Source_Unit (N)
5878 renames Scope_Stack.Table
5879 (Scope_Stack.Last).Last_Subprogram_Name;
5881 Body_Id : constant Entity_Id :=
5882 Defining_Entity (Specification (N));
5885 Get_Decoded_Name_String (Chars (Body_Id));
5888 if Subprogram_Name_Greater
5889 (LSN.all, Name_Buffer (1 .. Name_Len))
5891 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
5897 LSN := new String'(Name_Buffer (1 .. Name_Len));
5900 end Check_Subprogram_Order;
5902 ------------------------------
5903 -- Check_Subtype_Conformant --
5904 ------------------------------
5906 procedure Check_Subtype_Conformant
5907 (New_Id : Entity_Id;
5909 Err_Loc : Node_Id := Empty;
5910 Skip_Controlling_Formals : Boolean := False)
5913 pragma Warnings (Off, Result);
5916 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
5917 Skip_Controlling_Formals => Skip_Controlling_Formals);
5918 end Check_Subtype_Conformant;
5920 ---------------------------
5921 -- Check_Type_Conformant --
5922 ---------------------------
5924 procedure Check_Type_Conformant
5925 (New_Id : Entity_Id;
5927 Err_Loc : Node_Id := Empty)
5930 pragma Warnings (Off, Result);
5933 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
5934 end Check_Type_Conformant;
5936 ---------------------------
5937 -- Can_Override_Operator --
5938 ---------------------------
5940 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
5943 if Nkind (Subp) /= N_Defining_Operator_Symbol then
5947 Typ := Base_Type (Etype (First_Formal (Subp)));
5949 return Operator_Matches_Spec (Subp, Subp)
5950 and then Scope (Subp) = Scope (Typ)
5951 and then not Is_Class_Wide_Type (Typ);
5953 end Can_Override_Operator;
5955 ----------------------
5956 -- Conforming_Types --
5957 ----------------------
5959 function Conforming_Types
5962 Ctype : Conformance_Type;
5963 Get_Inst : Boolean := False) return Boolean
5965 Type_1 : Entity_Id := T1;
5966 Type_2 : Entity_Id := T2;
5967 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
5969 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
5970 -- If neither T1 nor T2 are generic actual types, or if they are in
5971 -- different scopes (e.g. parent and child instances), then verify that
5972 -- the base types are equal. Otherwise T1 and T2 must be on the same
5973 -- subtype chain. The whole purpose of this procedure is to prevent
5974 -- spurious ambiguities in an instantiation that may arise if two
5975 -- distinct generic types are instantiated with the same actual.
5977 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
5978 -- An access parameter can designate an incomplete type. If the
5979 -- incomplete type is the limited view of a type from a limited_
5980 -- with_clause, check whether the non-limited view is available. If
5981 -- it is a (non-limited) incomplete type, get the full view.
5983 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
5984 -- Returns True if and only if either T1 denotes a limited view of T2
5985 -- or T2 denotes a limited view of T1. This can arise when the limited
5986 -- with view of a type is used in a subprogram declaration and the
5987 -- subprogram body is in the scope of a regular with clause for the
5988 -- same unit. In such a case, the two type entities can be considered
5989 -- identical for purposes of conformance checking.
5991 ----------------------
5992 -- Base_Types_Match --
5993 ----------------------
5995 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
6000 elsif Base_Type (T1) = Base_Type (T2) then
6002 -- The following is too permissive. A more precise test should
6003 -- check that the generic actual is an ancestor subtype of the
6006 return not Is_Generic_Actual_Type (T1)
6007 or else not Is_Generic_Actual_Type (T2)
6008 or else Scope (T1) /= Scope (T2);
6013 end Base_Types_Match;
6015 --------------------------
6016 -- Find_Designated_Type --
6017 --------------------------
6019 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
6023 Desig := Directly_Designated_Type (T);
6025 if Ekind (Desig) = E_Incomplete_Type then
6027 -- If regular incomplete type, get full view if available
6029 if Present (Full_View (Desig)) then
6030 Desig := Full_View (Desig);
6032 -- If limited view of a type, get non-limited view if available,
6033 -- and check again for a regular incomplete type.
6035 elsif Present (Non_Limited_View (Desig)) then
6036 Desig := Get_Full_View (Non_Limited_View (Desig));
6041 end Find_Designated_Type;
6043 -------------------------------
6044 -- Matches_Limited_With_View --
6045 -------------------------------
6047 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
6049 -- In some cases a type imported through a limited_with clause, and
6050 -- its nonlimited view are both visible, for example in an anonymous
6051 -- access-to-class-wide type in a formal. Both entities designate the
6054 if From_With_Type (T1)
6055 and then T2 = Available_View (T1)
6059 elsif From_With_Type (T2)
6060 and then T1 = Available_View (T2)
6064 elsif From_With_Type (T1)
6065 and then From_With_Type (T2)
6066 and then Available_View (T1) = Available_View (T2)
6073 end Matches_Limited_With_View;
6075 -- Start of processing for Conforming_Types
6078 -- The context is an instance association for a formal
6079 -- access-to-subprogram type; the formal parameter types require
6080 -- mapping because they may denote other formal parameters of the
6084 Type_1 := Get_Instance_Of (T1);
6085 Type_2 := Get_Instance_Of (T2);
6088 -- If one of the types is a view of the other introduced by a limited
6089 -- with clause, treat these as conforming for all purposes.
6091 if Matches_Limited_With_View (T1, T2) then
6094 elsif Base_Types_Match (Type_1, Type_2) then
6095 return Ctype <= Mode_Conformant
6096 or else Subtypes_Statically_Match (Type_1, Type_2);
6098 elsif Is_Incomplete_Or_Private_Type (Type_1)
6099 and then Present (Full_View (Type_1))
6100 and then Base_Types_Match (Full_View (Type_1), Type_2)
6102 return Ctype <= Mode_Conformant
6103 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
6105 elsif Ekind (Type_2) = E_Incomplete_Type
6106 and then Present (Full_View (Type_2))
6107 and then Base_Types_Match (Type_1, Full_View (Type_2))
6109 return Ctype <= Mode_Conformant
6110 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
6112 elsif Is_Private_Type (Type_2)
6113 and then In_Instance
6114 and then Present (Full_View (Type_2))
6115 and then Base_Types_Match (Type_1, Full_View (Type_2))
6117 return Ctype <= Mode_Conformant
6118 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
6121 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
6122 -- treated recursively because they carry a signature.
6124 Are_Anonymous_Access_To_Subprogram_Types :=
6125 Ekind (Type_1) = Ekind (Type_2)
6127 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
6129 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
6131 -- Test anonymous access type case. For this case, static subtype
6132 -- matching is required for mode conformance (RM 6.3.1(15)). We check
6133 -- the base types because we may have built internal subtype entities
6134 -- to handle null-excluding types (see Process_Formals).
6136 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
6138 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
6139 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
6142 Desig_1 : Entity_Id;
6143 Desig_2 : Entity_Id;
6146 -- In Ada 2005, access constant indicators must match for
6147 -- subtype conformance.
6149 if Ada_Version >= Ada_2005
6150 and then Ctype >= Subtype_Conformant
6152 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
6157 Desig_1 := Find_Designated_Type (Type_1);
6158 Desig_2 := Find_Designated_Type (Type_2);
6160 -- If the context is an instance association for a formal
6161 -- access-to-subprogram type; formal access parameter designated
6162 -- types require mapping because they may denote other formal
6163 -- parameters of the generic unit.
6166 Desig_1 := Get_Instance_Of (Desig_1);
6167 Desig_2 := Get_Instance_Of (Desig_2);
6170 -- It is possible for a Class_Wide_Type to be introduced for an
6171 -- incomplete type, in which case there is a separate class_ wide
6172 -- type for the full view. The types conform if their Etypes
6173 -- conform, i.e. one may be the full view of the other. This can
6174 -- only happen in the context of an access parameter, other uses
6175 -- of an incomplete Class_Wide_Type are illegal.
6177 if Is_Class_Wide_Type (Desig_1)
6179 Is_Class_Wide_Type (Desig_2)
6183 (Etype (Base_Type (Desig_1)),
6184 Etype (Base_Type (Desig_2)), Ctype);
6186 elsif Are_Anonymous_Access_To_Subprogram_Types then
6187 if Ada_Version < Ada_2005 then
6188 return Ctype = Type_Conformant
6190 Subtypes_Statically_Match (Desig_1, Desig_2);
6192 -- We must check the conformance of the signatures themselves
6196 Conformant : Boolean;
6199 (Desig_1, Desig_2, Ctype, False, Conformant);
6205 return Base_Type (Desig_1) = Base_Type (Desig_2)
6206 and then (Ctype = Type_Conformant
6208 Subtypes_Statically_Match (Desig_1, Desig_2));
6212 -- Otherwise definitely no match
6215 if ((Ekind (Type_1) = E_Anonymous_Access_Type
6216 and then Is_Access_Type (Type_2))
6217 or else (Ekind (Type_2) = E_Anonymous_Access_Type
6218 and then Is_Access_Type (Type_1)))
6221 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
6223 May_Hide_Profile := True;
6228 end Conforming_Types;
6230 --------------------------
6231 -- Create_Extra_Formals --
6232 --------------------------
6234 procedure Create_Extra_Formals (E : Entity_Id) is
6236 First_Extra : Entity_Id := Empty;
6237 Last_Extra : Entity_Id;
6238 Formal_Type : Entity_Id;
6239 P_Formal : Entity_Id := Empty;
6241 function Add_Extra_Formal
6242 (Assoc_Entity : Entity_Id;
6245 Suffix : String) return Entity_Id;
6246 -- Add an extra formal to the current list of formals and extra formals.
6247 -- The extra formal is added to the end of the list of extra formals,
6248 -- and also returned as the result. These formals are always of mode IN.
6249 -- The new formal has the type Typ, is declared in Scope, and its name
6250 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
6251 -- The following suffixes are currently used. They should not be changed
6252 -- without coordinating with CodePeer, which makes use of these to
6253 -- provide better messages.
6255 -- O denotes the Constrained bit.
6256 -- L denotes the accessibility level.
6257 -- BIP_xxx denotes an extra formal for a build-in-place function. See
6258 -- the full list in exp_ch6.BIP_Formal_Kind.
6260 ----------------------
6261 -- Add_Extra_Formal --
6262 ----------------------
6264 function Add_Extra_Formal
6265 (Assoc_Entity : Entity_Id;
6268 Suffix : String) return Entity_Id
6270 EF : constant Entity_Id :=
6271 Make_Defining_Identifier (Sloc (Assoc_Entity),
6272 Chars => New_External_Name (Chars (Assoc_Entity),
6276 -- A little optimization. Never generate an extra formal for the
6277 -- _init operand of an initialization procedure, since it could
6280 if Chars (Formal) = Name_uInit then
6284 Set_Ekind (EF, E_In_Parameter);
6285 Set_Actual_Subtype (EF, Typ);
6286 Set_Etype (EF, Typ);
6287 Set_Scope (EF, Scope);
6288 Set_Mechanism (EF, Default_Mechanism);
6289 Set_Formal_Validity (EF);
6291 if No (First_Extra) then
6293 Set_Extra_Formals (Scope, First_Extra);
6296 if Present (Last_Extra) then
6297 Set_Extra_Formal (Last_Extra, EF);
6303 end Add_Extra_Formal;
6305 -- Start of processing for Create_Extra_Formals
6308 -- We never generate extra formals if expansion is not active
6309 -- because we don't need them unless we are generating code.
6311 if not Expander_Active then
6315 -- If this is a derived subprogram then the subtypes of the parent
6316 -- subprogram's formal parameters will be used to determine the need
6317 -- for extra formals.
6319 if Is_Overloadable (E) and then Present (Alias (E)) then
6320 P_Formal := First_Formal (Alias (E));
6323 Last_Extra := Empty;
6324 Formal := First_Formal (E);
6325 while Present (Formal) loop
6326 Last_Extra := Formal;
6327 Next_Formal (Formal);
6330 -- If Extra_formals were already created, don't do it again. This
6331 -- situation may arise for subprogram types created as part of
6332 -- dispatching calls (see Expand_Dispatching_Call)
6334 if Present (Last_Extra) and then
6335 Present (Extra_Formal (Last_Extra))
6340 -- If the subprogram is a predefined dispatching subprogram then don't
6341 -- generate any extra constrained or accessibility level formals. In
6342 -- general we suppress these for internal subprograms (by not calling
6343 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
6344 -- generated stream attributes do get passed through because extra
6345 -- build-in-place formals are needed in some cases (limited 'Input).
6347 if Is_Predefined_Internal_Operation (E) then
6348 goto Test_For_Func_Result_Extras;
6351 Formal := First_Formal (E);
6352 while Present (Formal) loop
6354 -- Create extra formal for supporting the attribute 'Constrained.
6355 -- The case of a private type view without discriminants also
6356 -- requires the extra formal if the underlying type has defaulted
6359 if Ekind (Formal) /= E_In_Parameter then
6360 if Present (P_Formal) then
6361 Formal_Type := Etype (P_Formal);
6363 Formal_Type := Etype (Formal);
6366 -- Do not produce extra formals for Unchecked_Union parameters.
6367 -- Jump directly to the end of the loop.
6369 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
6370 goto Skip_Extra_Formal_Generation;
6373 if not Has_Discriminants (Formal_Type)
6374 and then Ekind (Formal_Type) in Private_Kind
6375 and then Present (Underlying_Type (Formal_Type))
6377 Formal_Type := Underlying_Type (Formal_Type);
6380 -- Suppress the extra formal if formal's subtype is constrained or
6381 -- indefinite, or we're compiling for Ada 2012 and the underlying
6382 -- type is tagged and limited. In Ada 2012, a limited tagged type
6383 -- can have defaulted discriminants, but 'Constrained is required
6384 -- to return True, so the formal is never needed (see AI05-0214).
6385 -- Note that this ensures consistency of calling sequences for
6386 -- dispatching operations when some types in a class have defaults
6387 -- on discriminants and others do not (and requiring the extra
6388 -- formal would introduce distributed overhead).
6390 if Has_Discriminants (Formal_Type)
6391 and then not Is_Constrained (Formal_Type)
6392 and then not Is_Indefinite_Subtype (Formal_Type)
6393 and then (Ada_Version < Ada_2012
6395 not (Is_Tagged_Type (Underlying_Type (Formal_Type))
6396 and then Is_Limited_Type (Formal_Type)))
6398 Set_Extra_Constrained
6399 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
6403 -- Create extra formal for supporting accessibility checking. This
6404 -- is done for both anonymous access formals and formals of named
6405 -- access types that are marked as controlling formals. The latter
6406 -- case can occur when Expand_Dispatching_Call creates a subprogram
6407 -- type and substitutes the types of access-to-class-wide actuals
6408 -- for the anonymous access-to-specific-type of controlling formals.
6409 -- Base_Type is applied because in cases where there is a null
6410 -- exclusion the formal may have an access subtype.
6412 -- This is suppressed if we specifically suppress accessibility
6413 -- checks at the package level for either the subprogram, or the
6414 -- package in which it resides. However, we do not suppress it
6415 -- simply if the scope has accessibility checks suppressed, since
6416 -- this could cause trouble when clients are compiled with a
6417 -- different suppression setting. The explicit checks at the
6418 -- package level are safe from this point of view.
6420 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
6421 or else (Is_Controlling_Formal (Formal)
6422 and then Is_Access_Type (Base_Type (Etype (Formal)))))
6424 (Explicit_Suppress (E, Accessibility_Check)
6426 Explicit_Suppress (Scope (E), Accessibility_Check))
6429 or else Present (Extra_Accessibility (P_Formal)))
6431 Set_Extra_Accessibility
6432 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
6435 -- This label is required when skipping extra formal generation for
6436 -- Unchecked_Union parameters.
6438 <<Skip_Extra_Formal_Generation>>
6440 if Present (P_Formal) then
6441 Next_Formal (P_Formal);
6444 Next_Formal (Formal);
6447 <<Test_For_Func_Result_Extras>>
6449 -- Ada 2012 (AI05-234): "the accessibility level of the result of a
6450 -- function call is ... determined by the point of call ...".
6452 if Needs_Result_Accessibility_Level (E) then
6453 Set_Extra_Accessibility_Of_Result
6454 (E, Add_Extra_Formal (E, Standard_Natural, E, "L"));
6457 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
6458 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
6460 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
6462 Result_Subt : constant Entity_Id := Etype (E);
6464 Discard : Entity_Id;
6465 pragma Warnings (Off, Discard);
6468 -- In the case of functions with unconstrained result subtypes,
6469 -- add a 4-state formal indicating whether the return object is
6470 -- allocated by the caller (1), or should be allocated by the
6471 -- callee on the secondary stack (2), in the global heap (3), or
6472 -- in a user-defined storage pool (4). For the moment we just use
6473 -- Natural for the type of this formal. Note that this formal
6474 -- isn't usually needed in the case where the result subtype is
6475 -- constrained, but it is needed when the function has a tagged
6476 -- result, because generally such functions can be called in a
6477 -- dispatching context and such calls must be handled like calls
6478 -- to a class-wide function.
6480 if Needs_BIP_Alloc_Form (E) then
6483 (E, Standard_Natural,
6484 E, BIP_Formal_Suffix (BIP_Alloc_Form));
6486 -- Whenever we need BIP_Alloc_Form, we also need
6487 -- BIP_Storage_Pool, in case BIP_Alloc_Form indicates to use a
6488 -- user-defined pool.
6492 (E, RTE (RE_Root_Storage_Pool_Ptr),
6493 E, BIP_Formal_Suffix (BIP_Storage_Pool));
6496 -- In the case of functions whose result type needs finalization,
6497 -- add an extra formal which represents the finalization master.
6499 if Needs_BIP_Finalization_Master (E) then
6502 (E, RTE (RE_Finalization_Master_Ptr),
6503 E, BIP_Formal_Suffix (BIP_Finalization_Master));
6506 -- When the result type contains tasks, add two extra formals: the
6507 -- master of the tasks to be created, and the caller's activation
6510 if Has_Task (Available_View (Result_Subt)) then
6513 (E, RTE (RE_Master_Id),
6514 E, BIP_Formal_Suffix (BIP_Master));
6517 (E, RTE (RE_Activation_Chain_Access),
6518 E, BIP_Formal_Suffix (BIP_Activation_Chain));
6521 -- All build-in-place functions get an extra formal that will be
6522 -- passed the address of the return object within the caller.
6525 Formal_Type : constant Entity_Id :=
6527 (E_Anonymous_Access_Type, E,
6528 Scope_Id => Scope (E));
6530 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
6531 Set_Etype (Formal_Type, Formal_Type);
6532 Set_Depends_On_Private
6533 (Formal_Type, Has_Private_Component (Formal_Type));
6534 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
6535 Set_Is_Access_Constant (Formal_Type, False);
6537 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
6538 -- the designated type comes from the limited view (for
6539 -- back-end purposes).
6541 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
6543 Layout_Type (Formal_Type);
6547 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
6551 end Create_Extra_Formals;
6553 -----------------------------
6554 -- Enter_Overloaded_Entity --
6555 -----------------------------
6557 procedure Enter_Overloaded_Entity (S : Entity_Id) is
6558 E : Entity_Id := Current_Entity_In_Scope (S);
6559 C_E : Entity_Id := Current_Entity (S);
6563 Set_Has_Homonym (E);
6564 Set_Has_Homonym (S);
6567 Set_Is_Immediately_Visible (S);
6568 Set_Scope (S, Current_Scope);
6570 -- Chain new entity if front of homonym in current scope, so that
6571 -- homonyms are contiguous.
6576 while Homonym (C_E) /= E loop
6577 C_E := Homonym (C_E);
6580 Set_Homonym (C_E, S);
6584 Set_Current_Entity (S);
6589 Append_Entity (S, Current_Scope);
6590 Set_Public_Status (S);
6592 if Debug_Flag_E then
6593 Write_Str ("New overloaded entity chain: ");
6594 Write_Name (Chars (S));
6597 while Present (E) loop
6598 Write_Str (" "); Write_Int (Int (E));
6605 -- Generate warning for hiding
6608 and then Comes_From_Source (S)
6609 and then In_Extended_Main_Source_Unit (S)
6616 -- Warn unless genuine overloading. Do not emit warning on
6617 -- hiding predefined operators in Standard (these are either an
6618 -- (artifact of our implicit declarations, or simple noise) but
6619 -- keep warning on a operator defined on a local subtype, because
6620 -- of the real danger that different operators may be applied in
6621 -- various parts of the program.
6623 -- Note that if E and S have the same scope, there is never any
6624 -- hiding. Either the two conflict, and the program is illegal,
6625 -- or S is overriding an implicit inherited subprogram.
6627 if Scope (E) /= Scope (S)
6628 and then (not Is_Overloadable (E)
6629 or else Subtype_Conformant (E, S))
6630 and then (Is_Immediately_Visible (E)
6632 Is_Potentially_Use_Visible (S))
6634 if Scope (E) /= Standard_Standard then
6635 Error_Msg_Sloc := Sloc (E);
6636 Error_Msg_N ("declaration of & hides one#?", S);
6638 elsif Nkind (S) = N_Defining_Operator_Symbol
6640 Scope (Base_Type (Etype (First_Formal (S)))) /= Scope (S)
6643 ("declaration of & hides predefined operator?", S);
6648 end Enter_Overloaded_Entity;
6650 -----------------------------
6651 -- Check_Untagged_Equality --
6652 -----------------------------
6654 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
6655 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
6656 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
6660 if Nkind (Decl) = N_Subprogram_Declaration
6661 and then Is_Record_Type (Typ)
6662 and then not Is_Tagged_Type (Typ)
6664 -- If the type is not declared in a package, or if we are in the
6665 -- body of the package or in some other scope, the new operation is
6666 -- not primitive, and therefore legal, though suspicious. If the
6667 -- type is a generic actual (sub)type, the operation is not primitive
6668 -- either because the base type is declared elsewhere.
6670 if Is_Frozen (Typ) then
6671 if Ekind (Scope (Typ)) /= E_Package
6672 or else Scope (Typ) /= Current_Scope
6676 elsif Is_Generic_Actual_Type (Typ) then
6679 elsif In_Package_Body (Scope (Typ)) then
6681 ("equality operator must be declared "
6682 & "before type& is frozen", Eq_Op, Typ);
6684 ("\move declaration to package spec", Eq_Op);
6688 ("equality operator must be declared "
6689 & "before type& is frozen", Eq_Op, Typ);
6691 Obj_Decl := Next (Parent (Typ));
6692 while Present (Obj_Decl)
6693 and then Obj_Decl /= Decl
6695 if Nkind (Obj_Decl) = N_Object_Declaration
6696 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
6698 Error_Msg_NE ("type& is frozen by declaration?",
6701 ("\an equality operator cannot be declared after this "
6702 & "point (RM 4.5.2 (9.8)) (Ada 2012))?", Obj_Decl);
6710 elsif not In_Same_List (Parent (Typ), Decl)
6711 and then not Is_Limited_Type (Typ)
6714 -- This makes it illegal to have a primitive equality declared in
6715 -- the private part if the type is visible.
6717 Error_Msg_N ("equality operator appears too late", Eq_Op);
6720 end Check_Untagged_Equality;
6722 -----------------------------
6723 -- Find_Corresponding_Spec --
6724 -----------------------------
6726 function Find_Corresponding_Spec
6728 Post_Error : Boolean := True) return Entity_Id
6730 Spec : constant Node_Id := Specification (N);
6731 Designator : constant Entity_Id := Defining_Entity (Spec);
6736 E := Current_Entity (Designator);
6737 while Present (E) loop
6739 -- We are looking for a matching spec. It must have the same scope,
6740 -- and the same name, and either be type conformant, or be the case
6741 -- of a library procedure spec and its body (which belong to one
6742 -- another regardless of whether they are type conformant or not).
6744 if Scope (E) = Current_Scope then
6745 if Current_Scope = Standard_Standard
6746 or else (Ekind (E) = Ekind (Designator)
6747 and then Type_Conformant (E, Designator))
6749 -- Within an instantiation, we know that spec and body are
6750 -- subtype conformant, because they were subtype conformant
6751 -- in the generic. We choose the subtype-conformant entity
6752 -- here as well, to resolve spurious ambiguities in the
6753 -- instance that were not present in the generic (i.e. when
6754 -- two different types are given the same actual). If we are
6755 -- looking for a spec to match a body, full conformance is
6759 Set_Convention (Designator, Convention (E));
6761 -- Skip past subprogram bodies and subprogram renamings that
6762 -- may appear to have a matching spec, but that aren't fully
6763 -- conformant with it. That can occur in cases where an
6764 -- actual type causes unrelated homographs in the instance.
6766 if Nkind_In (N, N_Subprogram_Body,
6767 N_Subprogram_Renaming_Declaration)
6768 and then Present (Homonym (E))
6769 and then not Fully_Conformant (Designator, E)
6773 elsif not Subtype_Conformant (Designator, E) then
6778 -- Ada 2012 (AI05-0165): For internally generated bodies of
6779 -- null procedures locate the internally generated spec. We
6780 -- enforce mode conformance since a tagged type may inherit
6781 -- from interfaces several null primitives which differ only
6782 -- in the mode of the formals.
6784 if not (Comes_From_Source (E))
6785 and then Is_Null_Procedure (E)
6786 and then not Mode_Conformant (Designator, E)
6790 elsif not Has_Completion (E) then
6791 if Nkind (N) /= N_Subprogram_Body_Stub then
6792 Set_Corresponding_Spec (N, E);
6795 Set_Has_Completion (E);
6798 elsif Nkind (Parent (N)) = N_Subunit then
6800 -- If this is the proper body of a subunit, the completion
6801 -- flag is set when analyzing the stub.
6805 -- If E is an internal function with a controlling result
6806 -- that was created for an operation inherited by a null
6807 -- extension, it may be overridden by a body without a previous
6808 -- spec (one more reason why these should be shunned). In that
6809 -- case remove the generated body if present, because the
6810 -- current one is the explicit overriding.
6812 elsif Ekind (E) = E_Function
6813 and then Ada_Version >= Ada_2005
6814 and then not Comes_From_Source (E)
6815 and then Has_Controlling_Result (E)
6816 and then Is_Null_Extension (Etype (E))
6817 and then Comes_From_Source (Spec)
6819 Set_Has_Completion (E, False);
6822 and then Nkind (Parent (E)) = N_Function_Specification
6825 (Unit_Declaration_Node
6826 (Corresponding_Body (Unit_Declaration_Node (E))));
6830 -- If expansion is disabled, or if the wrapper function has
6831 -- not been generated yet, this a late body overriding an
6832 -- inherited operation, or it is an overriding by some other
6833 -- declaration before the controlling result is frozen. In
6834 -- either case this is a declaration of a new entity.
6840 -- If the body already exists, then this is an error unless
6841 -- the previous declaration is the implicit declaration of a
6842 -- derived subprogram. It is also legal for an instance to
6843 -- contain type conformant overloadable declarations (but the
6844 -- generic declaration may not), per 8.3(26/2).
6846 elsif No (Alias (E))
6847 and then not Is_Intrinsic_Subprogram (E)
6848 and then not In_Instance
6851 Error_Msg_Sloc := Sloc (E);
6853 if Is_Imported (E) then
6855 ("body not allowed for imported subprogram & declared#",
6858 Error_Msg_NE ("duplicate body for & declared#", N, E);
6862 -- Child units cannot be overloaded, so a conformance mismatch
6863 -- between body and a previous spec is an error.
6865 elsif Is_Child_Unit (E)
6867 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
6869 Nkind (Parent (Unit_Declaration_Node (Designator))) =
6874 ("body of child unit does not match previous declaration", N);
6882 -- On exit, we know that no previous declaration of subprogram exists
6885 end Find_Corresponding_Spec;
6887 ----------------------
6888 -- Fully_Conformant --
6889 ----------------------
6891 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6894 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
6896 end Fully_Conformant;
6898 ----------------------------------
6899 -- Fully_Conformant_Expressions --
6900 ----------------------------------
6902 function Fully_Conformant_Expressions
6903 (Given_E1 : Node_Id;
6904 Given_E2 : Node_Id) return Boolean
6906 E1 : constant Node_Id := Original_Node (Given_E1);
6907 E2 : constant Node_Id := Original_Node (Given_E2);
6908 -- We always test conformance on original nodes, since it is possible
6909 -- for analysis and/or expansion to make things look as though they
6910 -- conform when they do not, e.g. by converting 1+2 into 3.
6912 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
6913 renames Fully_Conformant_Expressions;
6915 function FCL (L1, L2 : List_Id) return Boolean;
6916 -- Compare elements of two lists for conformance. Elements have to
6917 -- be conformant, and actuals inserted as default parameters do not
6918 -- match explicit actuals with the same value.
6920 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
6921 -- Compare an operator node with a function call
6927 function FCL (L1, L2 : List_Id) return Boolean is
6931 if L1 = No_List then
6937 if L2 = No_List then
6943 -- Compare two lists, skipping rewrite insertions (we want to
6944 -- compare the original trees, not the expanded versions!)
6947 if Is_Rewrite_Insertion (N1) then
6949 elsif Is_Rewrite_Insertion (N2) then
6955 elsif not FCE (N1, N2) then
6968 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
6969 Actuals : constant List_Id := Parameter_Associations (Call_Node);
6974 or else Entity (Op_Node) /= Entity (Name (Call_Node))
6979 Act := First (Actuals);
6981 if Nkind (Op_Node) in N_Binary_Op then
6982 if not FCE (Left_Opnd (Op_Node), Act) then
6989 return Present (Act)
6990 and then FCE (Right_Opnd (Op_Node), Act)
6991 and then No (Next (Act));
6995 -- Start of processing for Fully_Conformant_Expressions
6998 -- Non-conformant if paren count does not match. Note: if some idiot
6999 -- complains that we don't do this right for more than 3 levels of
7000 -- parentheses, they will be treated with the respect they deserve!
7002 if Paren_Count (E1) /= Paren_Count (E2) then
7005 -- If same entities are referenced, then they are conformant even if
7006 -- they have different forms (RM 8.3.1(19-20)).
7008 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
7009 if Present (Entity (E1)) then
7010 return Entity (E1) = Entity (E2)
7011 or else (Chars (Entity (E1)) = Chars (Entity (E2))
7012 and then Ekind (Entity (E1)) = E_Discriminant
7013 and then Ekind (Entity (E2)) = E_In_Parameter);
7015 elsif Nkind (E1) = N_Expanded_Name
7016 and then Nkind (E2) = N_Expanded_Name
7017 and then Nkind (Selector_Name (E1)) = N_Character_Literal
7018 and then Nkind (Selector_Name (E2)) = N_Character_Literal
7020 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
7023 -- Identifiers in component associations don't always have
7024 -- entities, but their names must conform.
7026 return Nkind (E1) = N_Identifier
7027 and then Nkind (E2) = N_Identifier
7028 and then Chars (E1) = Chars (E2);
7031 elsif Nkind (E1) = N_Character_Literal
7032 and then Nkind (E2) = N_Expanded_Name
7034 return Nkind (Selector_Name (E2)) = N_Character_Literal
7035 and then Chars (E1) = Chars (Selector_Name (E2));
7037 elsif Nkind (E2) = N_Character_Literal
7038 and then Nkind (E1) = N_Expanded_Name
7040 return Nkind (Selector_Name (E1)) = N_Character_Literal
7041 and then Chars (E2) = Chars (Selector_Name (E1));
7043 elsif Nkind (E1) in N_Op
7044 and then Nkind (E2) = N_Function_Call
7046 return FCO (E1, E2);
7048 elsif Nkind (E2) in N_Op
7049 and then Nkind (E1) = N_Function_Call
7051 return FCO (E2, E1);
7053 -- Otherwise we must have the same syntactic entity
7055 elsif Nkind (E1) /= Nkind (E2) then
7058 -- At this point, we specialize by node type
7065 FCL (Expressions (E1), Expressions (E2))
7067 FCL (Component_Associations (E1),
7068 Component_Associations (E2));
7071 if Nkind (Expression (E1)) = N_Qualified_Expression
7073 Nkind (Expression (E2)) = N_Qualified_Expression
7075 return FCE (Expression (E1), Expression (E2));
7077 -- Check that the subtype marks and any constraints
7082 Indic1 : constant Node_Id := Expression (E1);
7083 Indic2 : constant Node_Id := Expression (E2);
7088 if Nkind (Indic1) /= N_Subtype_Indication then
7090 Nkind (Indic2) /= N_Subtype_Indication
7091 and then Entity (Indic1) = Entity (Indic2);
7093 elsif Nkind (Indic2) /= N_Subtype_Indication then
7095 Nkind (Indic1) /= N_Subtype_Indication
7096 and then Entity (Indic1) = Entity (Indic2);
7099 if Entity (Subtype_Mark (Indic1)) /=
7100 Entity (Subtype_Mark (Indic2))
7105 Elt1 := First (Constraints (Constraint (Indic1)));
7106 Elt2 := First (Constraints (Constraint (Indic2)));
7107 while Present (Elt1) and then Present (Elt2) loop
7108 if not FCE (Elt1, Elt2) then
7121 when N_Attribute_Reference =>
7123 Attribute_Name (E1) = Attribute_Name (E2)
7124 and then FCL (Expressions (E1), Expressions (E2));
7128 Entity (E1) = Entity (E2)
7129 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
7130 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
7132 when N_Short_Circuit | N_Membership_Test =>
7134 FCE (Left_Opnd (E1), Left_Opnd (E2))
7136 FCE (Right_Opnd (E1), Right_Opnd (E2));
7138 when N_Case_Expression =>
7144 if not FCE (Expression (E1), Expression (E2)) then
7148 Alt1 := First (Alternatives (E1));
7149 Alt2 := First (Alternatives (E2));
7151 if Present (Alt1) /= Present (Alt2) then
7153 elsif No (Alt1) then
7157 if not FCE (Expression (Alt1), Expression (Alt2))
7158 or else not FCL (Discrete_Choices (Alt1),
7159 Discrete_Choices (Alt2))
7170 when N_Character_Literal =>
7172 Char_Literal_Value (E1) = Char_Literal_Value (E2);
7174 when N_Component_Association =>
7176 FCL (Choices (E1), Choices (E2))
7178 FCE (Expression (E1), Expression (E2));
7180 when N_Conditional_Expression =>
7182 FCL (Expressions (E1), Expressions (E2));
7184 when N_Explicit_Dereference =>
7186 FCE (Prefix (E1), Prefix (E2));
7188 when N_Extension_Aggregate =>
7190 FCL (Expressions (E1), Expressions (E2))
7191 and then Null_Record_Present (E1) =
7192 Null_Record_Present (E2)
7193 and then FCL (Component_Associations (E1),
7194 Component_Associations (E2));
7196 when N_Function_Call =>
7198 FCE (Name (E1), Name (E2))
7200 FCL (Parameter_Associations (E1),
7201 Parameter_Associations (E2));
7203 when N_Indexed_Component =>
7205 FCE (Prefix (E1), Prefix (E2))
7207 FCL (Expressions (E1), Expressions (E2));
7209 when N_Integer_Literal =>
7210 return (Intval (E1) = Intval (E2));
7215 when N_Operator_Symbol =>
7217 Chars (E1) = Chars (E2);
7219 when N_Others_Choice =>
7222 when N_Parameter_Association =>
7224 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
7225 and then FCE (Explicit_Actual_Parameter (E1),
7226 Explicit_Actual_Parameter (E2));
7228 when N_Qualified_Expression =>
7230 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
7232 FCE (Expression (E1), Expression (E2));
7234 when N_Quantified_Expression =>
7235 if not FCE (Condition (E1), Condition (E2)) then
7239 if Present (Loop_Parameter_Specification (E1))
7240 and then Present (Loop_Parameter_Specification (E2))
7243 L1 : constant Node_Id :=
7244 Loop_Parameter_Specification (E1);
7245 L2 : constant Node_Id :=
7246 Loop_Parameter_Specification (E2);
7250 Reverse_Present (L1) = Reverse_Present (L2)
7252 FCE (Defining_Identifier (L1),
7253 Defining_Identifier (L2))
7255 FCE (Discrete_Subtype_Definition (L1),
7256 Discrete_Subtype_Definition (L2));
7259 else -- quantified expression with an iterator
7261 I1 : constant Node_Id := Iterator_Specification (E1);
7262 I2 : constant Node_Id := Iterator_Specification (E2);
7266 FCE (Defining_Identifier (I1),
7267 Defining_Identifier (I2))
7269 Of_Present (I1) = Of_Present (I2)
7271 Reverse_Present (I1) = Reverse_Present (I2)
7272 and then FCE (Name (I1), Name (I2))
7273 and then FCE (Subtype_Indication (I1),
7274 Subtype_Indication (I2));
7280 FCE (Low_Bound (E1), Low_Bound (E2))
7282 FCE (High_Bound (E1), High_Bound (E2));
7284 when N_Real_Literal =>
7285 return (Realval (E1) = Realval (E2));
7287 when N_Selected_Component =>
7289 FCE (Prefix (E1), Prefix (E2))
7291 FCE (Selector_Name (E1), Selector_Name (E2));
7295 FCE (Prefix (E1), Prefix (E2))
7297 FCE (Discrete_Range (E1), Discrete_Range (E2));
7299 when N_String_Literal =>
7301 S1 : constant String_Id := Strval (E1);
7302 S2 : constant String_Id := Strval (E2);
7303 L1 : constant Nat := String_Length (S1);
7304 L2 : constant Nat := String_Length (S2);
7311 for J in 1 .. L1 loop
7312 if Get_String_Char (S1, J) /=
7313 Get_String_Char (S2, J)
7323 when N_Type_Conversion =>
7325 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
7327 FCE (Expression (E1), Expression (E2));
7331 Entity (E1) = Entity (E2)
7333 FCE (Right_Opnd (E1), Right_Opnd (E2));
7335 when N_Unchecked_Type_Conversion =>
7337 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
7339 FCE (Expression (E1), Expression (E2));
7341 -- All other node types cannot appear in this context. Strictly
7342 -- we should raise a fatal internal error. Instead we just ignore
7343 -- the nodes. This means that if anyone makes a mistake in the
7344 -- expander and mucks an expression tree irretrievably, the
7345 -- result will be a failure to detect a (probably very obscure)
7346 -- case of non-conformance, which is better than bombing on some
7347 -- case where two expressions do in fact conform.
7354 end Fully_Conformant_Expressions;
7356 ----------------------------------------
7357 -- Fully_Conformant_Discrete_Subtypes --
7358 ----------------------------------------
7360 function Fully_Conformant_Discrete_Subtypes
7361 (Given_S1 : Node_Id;
7362 Given_S2 : Node_Id) return Boolean
7364 S1 : constant Node_Id := Original_Node (Given_S1);
7365 S2 : constant Node_Id := Original_Node (Given_S2);
7367 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
7368 -- Special-case for a bound given by a discriminant, which in the body
7369 -- is replaced with the discriminal of the enclosing type.
7371 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
7372 -- Check both bounds
7374 -----------------------
7375 -- Conforming_Bounds --
7376 -----------------------
7378 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
7380 if Is_Entity_Name (B1)
7381 and then Is_Entity_Name (B2)
7382 and then Ekind (Entity (B1)) = E_Discriminant
7384 return Chars (B1) = Chars (B2);
7387 return Fully_Conformant_Expressions (B1, B2);
7389 end Conforming_Bounds;
7391 -----------------------
7392 -- Conforming_Ranges --
7393 -----------------------
7395 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
7398 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
7400 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
7401 end Conforming_Ranges;
7403 -- Start of processing for Fully_Conformant_Discrete_Subtypes
7406 if Nkind (S1) /= Nkind (S2) then
7409 elsif Is_Entity_Name (S1) then
7410 return Entity (S1) = Entity (S2);
7412 elsif Nkind (S1) = N_Range then
7413 return Conforming_Ranges (S1, S2);
7415 elsif Nkind (S1) = N_Subtype_Indication then
7417 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
7420 (Range_Expression (Constraint (S1)),
7421 Range_Expression (Constraint (S2)));
7425 end Fully_Conformant_Discrete_Subtypes;
7427 --------------------
7428 -- Install_Entity --
7429 --------------------
7431 procedure Install_Entity (E : Entity_Id) is
7432 Prev : constant Entity_Id := Current_Entity (E);
7434 Set_Is_Immediately_Visible (E);
7435 Set_Current_Entity (E);
7436 Set_Homonym (E, Prev);
7439 ---------------------
7440 -- Install_Formals --
7441 ---------------------
7443 procedure Install_Formals (Id : Entity_Id) is
7446 F := First_Formal (Id);
7447 while Present (F) loop
7451 end Install_Formals;
7453 -----------------------------
7454 -- Is_Interface_Conformant --
7455 -----------------------------
7457 function Is_Interface_Conformant
7458 (Tagged_Type : Entity_Id;
7459 Iface_Prim : Entity_Id;
7460 Prim : Entity_Id) return Boolean
7462 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
7463 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
7465 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
7466 -- Return the controlling formal of Prim
7468 ------------------------
7469 -- Controlling_Formal --
7470 ------------------------
7472 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
7473 E : Entity_Id := First_Entity (Prim);
7476 while Present (E) loop
7477 if Is_Formal (E) and then Is_Controlling_Formal (E) then
7485 end Controlling_Formal;
7489 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
7490 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
7492 -- Start of processing for Is_Interface_Conformant
7495 pragma Assert (Is_Subprogram (Iface_Prim)
7496 and then Is_Subprogram (Prim)
7497 and then Is_Dispatching_Operation (Iface_Prim)
7498 and then Is_Dispatching_Operation (Prim));
7500 pragma Assert (Is_Interface (Iface)
7501 or else (Present (Alias (Iface_Prim))
7504 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
7506 if Prim = Iface_Prim
7507 or else not Is_Subprogram (Prim)
7508 or else Ekind (Prim) /= Ekind (Iface_Prim)
7509 or else not Is_Dispatching_Operation (Prim)
7510 or else Scope (Prim) /= Scope (Tagged_Type)
7512 or else Base_Type (Typ) /= Tagged_Type
7513 or else not Primitive_Names_Match (Iface_Prim, Prim)
7517 -- The mode of the controlling formals must match
7519 elsif Present (Iface_Ctrl_F)
7520 and then Present (Prim_Ctrl_F)
7521 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
7525 -- Case of a procedure, or a function whose result type matches the
7526 -- result type of the interface primitive, or a function that has no
7527 -- controlling result (I or access I).
7529 elsif Ekind (Iface_Prim) = E_Procedure
7530 or else Etype (Prim) = Etype (Iface_Prim)
7531 or else not Has_Controlling_Result (Prim)
7533 return Type_Conformant
7534 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
7536 -- Case of a function returning an interface, or an access to one.
7537 -- Check that the return types correspond.
7539 elsif Implements_Interface (Typ, Iface) then
7540 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
7542 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
7547 Type_Conformant (Prim, Iface_Prim,
7548 Skip_Controlling_Formals => True);
7554 end Is_Interface_Conformant;
7556 ---------------------------------
7557 -- Is_Non_Overriding_Operation --
7558 ---------------------------------
7560 function Is_Non_Overriding_Operation
7561 (Prev_E : Entity_Id;
7562 New_E : Entity_Id) return Boolean
7566 G_Typ : Entity_Id := Empty;
7568 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
7569 -- If F_Type is a derived type associated with a generic actual subtype,
7570 -- then return its Generic_Parent_Type attribute, else return Empty.
7572 function Types_Correspond
7573 (P_Type : Entity_Id;
7574 N_Type : Entity_Id) return Boolean;
7575 -- Returns true if and only if the types (or designated types in the
7576 -- case of anonymous access types) are the same or N_Type is derived
7577 -- directly or indirectly from P_Type.
7579 -----------------------------
7580 -- Get_Generic_Parent_Type --
7581 -----------------------------
7583 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
7589 if Is_Derived_Type (F_Typ)
7590 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
7592 -- The tree must be traversed to determine the parent subtype in
7593 -- the generic unit, which unfortunately isn't always available
7594 -- via semantic attributes. ??? (Note: The use of Original_Node
7595 -- is needed for cases where a full derived type has been
7598 Defn := Type_Definition (Original_Node (Parent (F_Typ)));
7599 if Nkind (Defn) = N_Derived_Type_Definition then
7600 Indic := Subtype_Indication (Defn);
7602 if Nkind (Indic) = N_Subtype_Indication then
7603 G_Typ := Entity (Subtype_Mark (Indic));
7605 G_Typ := Entity (Indic);
7608 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
7609 and then Present (Generic_Parent_Type (Parent (G_Typ)))
7611 return Generic_Parent_Type (Parent (G_Typ));
7617 end Get_Generic_Parent_Type;
7619 ----------------------
7620 -- Types_Correspond --
7621 ----------------------
7623 function Types_Correspond
7624 (P_Type : Entity_Id;
7625 N_Type : Entity_Id) return Boolean
7627 Prev_Type : Entity_Id := Base_Type (P_Type);
7628 New_Type : Entity_Id := Base_Type (N_Type);
7631 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
7632 Prev_Type := Designated_Type (Prev_Type);
7635 if Ekind (New_Type) = E_Anonymous_Access_Type then
7636 New_Type := Designated_Type (New_Type);
7639 if Prev_Type = New_Type then
7642 elsif not Is_Class_Wide_Type (New_Type) then
7643 while Etype (New_Type) /= New_Type loop
7644 New_Type := Etype (New_Type);
7645 if New_Type = Prev_Type then
7651 end Types_Correspond;
7653 -- Start of processing for Is_Non_Overriding_Operation
7656 -- In the case where both operations are implicit derived subprograms
7657 -- then neither overrides the other. This can only occur in certain
7658 -- obscure cases (e.g., derivation from homographs created in a generic
7661 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
7664 elsif Ekind (Current_Scope) = E_Package
7665 and then Is_Generic_Instance (Current_Scope)
7666 and then In_Private_Part (Current_Scope)
7667 and then Comes_From_Source (New_E)
7669 -- We examine the formals and result type of the inherited operation,
7670 -- to determine whether their type is derived from (the instance of)
7671 -- a generic type. The first such formal or result type is the one
7674 Formal := First_Formal (Prev_E);
7675 while Present (Formal) loop
7676 F_Typ := Base_Type (Etype (Formal));
7678 if Ekind (F_Typ) = E_Anonymous_Access_Type then
7679 F_Typ := Designated_Type (F_Typ);
7682 G_Typ := Get_Generic_Parent_Type (F_Typ);
7683 exit when Present (G_Typ);
7685 Next_Formal (Formal);
7688 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
7689 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
7696 -- If the generic type is a private type, then the original operation
7697 -- was not overriding in the generic, because there was no primitive
7698 -- operation to override.
7700 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
7701 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
7702 N_Formal_Private_Type_Definition
7706 -- The generic parent type is the ancestor of a formal derived
7707 -- type declaration. We need to check whether it has a primitive
7708 -- operation that should be overridden by New_E in the generic.
7712 P_Formal : Entity_Id;
7713 N_Formal : Entity_Id;
7717 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
7720 while Present (Prim_Elt) loop
7721 P_Prim := Node (Prim_Elt);
7723 if Chars (P_Prim) = Chars (New_E)
7724 and then Ekind (P_Prim) = Ekind (New_E)
7726 P_Formal := First_Formal (P_Prim);
7727 N_Formal := First_Formal (New_E);
7728 while Present (P_Formal) and then Present (N_Formal) loop
7729 P_Typ := Etype (P_Formal);
7730 N_Typ := Etype (N_Formal);
7732 if not Types_Correspond (P_Typ, N_Typ) then
7736 Next_Entity (P_Formal);
7737 Next_Entity (N_Formal);
7740 -- Found a matching primitive operation belonging to the
7741 -- formal ancestor type, so the new subprogram is
7745 and then No (N_Formal)
7746 and then (Ekind (New_E) /= E_Function
7749 (Etype (P_Prim), Etype (New_E)))
7755 Next_Elmt (Prim_Elt);
7758 -- If no match found, then the new subprogram does not
7759 -- override in the generic (nor in the instance).
7767 end Is_Non_Overriding_Operation;
7769 -------------------------------------
7770 -- List_Inherited_Pre_Post_Aspects --
7771 -------------------------------------
7773 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
7775 if Opt.List_Inherited_Aspects
7776 and then (Is_Subprogram (E) or else Is_Generic_Subprogram (E))
7779 Inherited : constant Subprogram_List :=
7780 Inherited_Subprograms (E);
7784 for J in Inherited'Range loop
7785 P := Spec_PPC_List (Contract (Inherited (J)));
7787 while Present (P) loop
7788 Error_Msg_Sloc := Sloc (P);
7790 if Class_Present (P) and then not Split_PPC (P) then
7791 if Pragma_Name (P) = Name_Precondition then
7793 ("?info: & inherits `Pre''Class` aspect from #", E);
7796 ("?info: & inherits `Post''Class` aspect from #", E);
7800 P := Next_Pragma (P);
7805 end List_Inherited_Pre_Post_Aspects;
7807 ------------------------------
7808 -- Make_Inequality_Operator --
7809 ------------------------------
7811 -- S is the defining identifier of an equality operator. We build a
7812 -- subprogram declaration with the right signature. This operation is
7813 -- intrinsic, because it is always expanded as the negation of the
7814 -- call to the equality function.
7816 procedure Make_Inequality_Operator (S : Entity_Id) is
7817 Loc : constant Source_Ptr := Sloc (S);
7820 Op_Name : Entity_Id;
7822 FF : constant Entity_Id := First_Formal (S);
7823 NF : constant Entity_Id := Next_Formal (FF);
7826 -- Check that equality was properly defined, ignore call if not
7833 A : constant Entity_Id :=
7834 Make_Defining_Identifier (Sloc (FF),
7835 Chars => Chars (FF));
7837 B : constant Entity_Id :=
7838 Make_Defining_Identifier (Sloc (NF),
7839 Chars => Chars (NF));
7842 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
7844 Formals := New_List (
7845 Make_Parameter_Specification (Loc,
7846 Defining_Identifier => A,
7848 New_Reference_To (Etype (First_Formal (S)),
7849 Sloc (Etype (First_Formal (S))))),
7851 Make_Parameter_Specification (Loc,
7852 Defining_Identifier => B,
7854 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
7855 Sloc (Etype (Next_Formal (First_Formal (S)))))));
7858 Make_Subprogram_Declaration (Loc,
7860 Make_Function_Specification (Loc,
7861 Defining_Unit_Name => Op_Name,
7862 Parameter_Specifications => Formals,
7863 Result_Definition =>
7864 New_Reference_To (Standard_Boolean, Loc)));
7866 -- Insert inequality right after equality if it is explicit or after
7867 -- the derived type when implicit. These entities are created only
7868 -- for visibility purposes, and eventually replaced in the course of
7869 -- expansion, so they do not need to be attached to the tree and seen
7870 -- by the back-end. Keeping them internal also avoids spurious
7871 -- freezing problems. The declaration is inserted in the tree for
7872 -- analysis, and removed afterwards. If the equality operator comes
7873 -- from an explicit declaration, attach the inequality immediately
7874 -- after. Else the equality is inherited from a derived type
7875 -- declaration, so insert inequality after that declaration.
7877 if No (Alias (S)) then
7878 Insert_After (Unit_Declaration_Node (S), Decl);
7879 elsif Is_List_Member (Parent (S)) then
7880 Insert_After (Parent (S), Decl);
7882 Insert_After (Parent (Etype (First_Formal (S))), Decl);
7885 Mark_Rewrite_Insertion (Decl);
7886 Set_Is_Intrinsic_Subprogram (Op_Name);
7889 Set_Has_Completion (Op_Name);
7890 Set_Corresponding_Equality (Op_Name, S);
7891 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
7893 end Make_Inequality_Operator;
7895 ----------------------
7896 -- May_Need_Actuals --
7897 ----------------------
7899 procedure May_Need_Actuals (Fun : Entity_Id) is
7904 F := First_Formal (Fun);
7906 while Present (F) loop
7907 if No (Default_Value (F)) then
7915 Set_Needs_No_Actuals (Fun, B);
7916 end May_Need_Actuals;
7918 ---------------------
7919 -- Mode_Conformant --
7920 ---------------------
7922 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7925 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
7927 end Mode_Conformant;
7929 ---------------------------
7930 -- New_Overloaded_Entity --
7931 ---------------------------
7933 procedure New_Overloaded_Entity
7935 Derived_Type : Entity_Id := Empty)
7937 Overridden_Subp : Entity_Id := Empty;
7938 -- Set if the current scope has an operation that is type-conformant
7939 -- with S, and becomes hidden by S.
7941 Is_Primitive_Subp : Boolean;
7942 -- Set to True if the new subprogram is primitive
7945 -- Entity that S overrides
7947 Prev_Vis : Entity_Id := Empty;
7948 -- Predecessor of E in Homonym chain
7950 procedure Check_For_Primitive_Subprogram
7951 (Is_Primitive : out Boolean;
7952 Is_Overriding : Boolean := False);
7953 -- If the subprogram being analyzed is a primitive operation of the type
7954 -- of a formal or result, set the Has_Primitive_Operations flag on the
7955 -- type, and set Is_Primitive to True (otherwise set to False). Set the
7956 -- corresponding flag on the entity itself for later use.
7958 procedure Check_Synchronized_Overriding
7959 (Def_Id : Entity_Id;
7960 Overridden_Subp : out Entity_Id);
7961 -- First determine if Def_Id is an entry or a subprogram either defined
7962 -- in the scope of a task or protected type, or is a primitive of such
7963 -- a type. Check whether Def_Id overrides a subprogram of an interface
7964 -- implemented by the synchronized type, return the overridden entity
7967 function Is_Private_Declaration (E : Entity_Id) return Boolean;
7968 -- Check that E is declared in the private part of the current package,
7969 -- or in the package body, where it may hide a previous declaration.
7970 -- We can't use In_Private_Part by itself because this flag is also
7971 -- set when freezing entities, so we must examine the place of the
7972 -- declaration in the tree, and recognize wrapper packages as well.
7974 function Is_Overriding_Alias
7976 New_E : Entity_Id) return Boolean;
7977 -- Check whether new subprogram and old subprogram are both inherited
7978 -- from subprograms that have distinct dispatch table entries. This can
7979 -- occur with derivations from instances with accidental homonyms.
7980 -- The function is conservative given that the converse is only true
7981 -- within instances that contain accidental overloadings.
7983 ------------------------------------
7984 -- Check_For_Primitive_Subprogram --
7985 ------------------------------------
7987 procedure Check_For_Primitive_Subprogram
7988 (Is_Primitive : out Boolean;
7989 Is_Overriding : Boolean := False)
7995 function Visible_Part_Type (T : Entity_Id) return Boolean;
7996 -- Returns true if T is declared in the visible part of the current
7997 -- package scope; otherwise returns false. Assumes that T is declared
8000 procedure Check_Private_Overriding (T : Entity_Id);
8001 -- Checks that if a primitive abstract subprogram of a visible
8002 -- abstract type is declared in a private part, then it must override
8003 -- an abstract subprogram declared in the visible part. Also checks
8004 -- that if a primitive function with a controlling result is declared
8005 -- in a private part, then it must override a function declared in
8006 -- the visible part.
8008 ------------------------------
8009 -- Check_Private_Overriding --
8010 ------------------------------
8012 procedure Check_Private_Overriding (T : Entity_Id) is
8014 if Is_Package_Or_Generic_Package (Current_Scope)
8015 and then In_Private_Part (Current_Scope)
8016 and then Visible_Part_Type (T)
8017 and then not In_Instance
8019 if Is_Abstract_Type (T)
8020 and then Is_Abstract_Subprogram (S)
8021 and then (not Is_Overriding
8022 or else not Is_Abstract_Subprogram (E))
8025 ("abstract subprograms must be visible "
8026 & "(RM 3.9.3(10))!", S);
8028 elsif Ekind (S) = E_Function
8029 and then not Is_Overriding
8031 if Is_Tagged_Type (T)
8032 and then T = Base_Type (Etype (S))
8035 ("private function with tagged result must"
8036 & " override visible-part function", S);
8038 ("\move subprogram to the visible part"
8039 & " (RM 3.9.3(10))", S);
8041 -- AI05-0073: extend this test to the case of a function
8042 -- with a controlling access result.
8044 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
8045 and then Is_Tagged_Type (Designated_Type (Etype (S)))
8047 not Is_Class_Wide_Type (Designated_Type (Etype (S)))
8048 and then Ada_Version >= Ada_2012
8051 ("private function with controlling access result "
8052 & "must override visible-part function", S);
8054 ("\move subprogram to the visible part"
8055 & " (RM 3.9.3(10))", S);
8059 end Check_Private_Overriding;
8061 -----------------------
8062 -- Visible_Part_Type --
8063 -----------------------
8065 function Visible_Part_Type (T : Entity_Id) return Boolean is
8066 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
8070 -- If the entity is a private type, then it must be declared in a
8073 if Ekind (T) in Private_Kind then
8077 -- Otherwise, we traverse the visible part looking for its
8078 -- corresponding declaration. We cannot use the declaration
8079 -- node directly because in the private part the entity of a
8080 -- private type is the one in the full view, which does not
8081 -- indicate that it is the completion of something visible.
8083 N := First (Visible_Declarations (Specification (P)));
8084 while Present (N) loop
8085 if Nkind (N) = N_Full_Type_Declaration
8086 and then Present (Defining_Identifier (N))
8087 and then T = Defining_Identifier (N)
8091 elsif Nkind_In (N, N_Private_Type_Declaration,
8092 N_Private_Extension_Declaration)
8093 and then Present (Defining_Identifier (N))
8094 and then T = Full_View (Defining_Identifier (N))
8103 end Visible_Part_Type;
8105 -- Start of processing for Check_For_Primitive_Subprogram
8108 Is_Primitive := False;
8110 if not Comes_From_Source (S) then
8113 -- If subprogram is at library level, it is not primitive operation
8115 elsif Current_Scope = Standard_Standard then
8118 elsif (Is_Package_Or_Generic_Package (Current_Scope)
8119 and then not In_Package_Body (Current_Scope))
8120 or else Is_Overriding
8122 -- For function, check return type
8124 if Ekind (S) = E_Function then
8125 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
8126 F_Typ := Designated_Type (Etype (S));
8131 B_Typ := Base_Type (F_Typ);
8133 if Scope (B_Typ) = Current_Scope
8134 and then not Is_Class_Wide_Type (B_Typ)
8135 and then not Is_Generic_Type (B_Typ)
8137 Is_Primitive := True;
8138 Set_Has_Primitive_Operations (B_Typ);
8139 Set_Is_Primitive (S);
8140 Check_Private_Overriding (B_Typ);
8144 -- For all subprograms, check formals
8146 Formal := First_Formal (S);
8147 while Present (Formal) loop
8148 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
8149 F_Typ := Designated_Type (Etype (Formal));
8151 F_Typ := Etype (Formal);
8154 B_Typ := Base_Type (F_Typ);
8156 if Ekind (B_Typ) = E_Access_Subtype then
8157 B_Typ := Base_Type (B_Typ);
8160 if Scope (B_Typ) = Current_Scope
8161 and then not Is_Class_Wide_Type (B_Typ)
8162 and then not Is_Generic_Type (B_Typ)
8164 Is_Primitive := True;
8165 Set_Is_Primitive (S);
8166 Set_Has_Primitive_Operations (B_Typ);
8167 Check_Private_Overriding (B_Typ);
8170 Next_Formal (Formal);
8173 end Check_For_Primitive_Subprogram;
8175 -----------------------------------
8176 -- Check_Synchronized_Overriding --
8177 -----------------------------------
8179 procedure Check_Synchronized_Overriding
8180 (Def_Id : Entity_Id;
8181 Overridden_Subp : out Entity_Id)
8183 Ifaces_List : Elist_Id;
8187 function Matches_Prefixed_View_Profile
8188 (Prim_Params : List_Id;
8189 Iface_Params : List_Id) return Boolean;
8190 -- Determine whether a subprogram's parameter profile Prim_Params
8191 -- matches that of a potentially overridden interface subprogram
8192 -- Iface_Params. Also determine if the type of first parameter of
8193 -- Iface_Params is an implemented interface.
8195 -----------------------------------
8196 -- Matches_Prefixed_View_Profile --
8197 -----------------------------------
8199 function Matches_Prefixed_View_Profile
8200 (Prim_Params : List_Id;
8201 Iface_Params : List_Id) return Boolean
8203 Iface_Id : Entity_Id;
8204 Iface_Param : Node_Id;
8205 Iface_Typ : Entity_Id;
8206 Prim_Id : Entity_Id;
8207 Prim_Param : Node_Id;
8208 Prim_Typ : Entity_Id;
8210 function Is_Implemented
8211 (Ifaces_List : Elist_Id;
8212 Iface : Entity_Id) return Boolean;
8213 -- Determine if Iface is implemented by the current task or
8216 --------------------
8217 -- Is_Implemented --
8218 --------------------
8220 function Is_Implemented
8221 (Ifaces_List : Elist_Id;
8222 Iface : Entity_Id) return Boolean
8224 Iface_Elmt : Elmt_Id;
8227 Iface_Elmt := First_Elmt (Ifaces_List);
8228 while Present (Iface_Elmt) loop
8229 if Node (Iface_Elmt) = Iface then
8233 Next_Elmt (Iface_Elmt);
8239 -- Start of processing for Matches_Prefixed_View_Profile
8242 Iface_Param := First (Iface_Params);
8243 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
8245 if Is_Access_Type (Iface_Typ) then
8246 Iface_Typ := Designated_Type (Iface_Typ);
8249 Prim_Param := First (Prim_Params);
8251 -- The first parameter of the potentially overridden subprogram
8252 -- must be an interface implemented by Prim.
8254 if not Is_Interface (Iface_Typ)
8255 or else not Is_Implemented (Ifaces_List, Iface_Typ)
8260 -- The checks on the object parameters are done, move onto the
8261 -- rest of the parameters.
8263 if not In_Scope then
8264 Prim_Param := Next (Prim_Param);
8267 Iface_Param := Next (Iface_Param);
8268 while Present (Iface_Param) and then Present (Prim_Param) loop
8269 Iface_Id := Defining_Identifier (Iface_Param);
8270 Iface_Typ := Find_Parameter_Type (Iface_Param);
8272 Prim_Id := Defining_Identifier (Prim_Param);
8273 Prim_Typ := Find_Parameter_Type (Prim_Param);
8275 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
8276 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
8277 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
8279 Iface_Typ := Designated_Type (Iface_Typ);
8280 Prim_Typ := Designated_Type (Prim_Typ);
8283 -- Case of multiple interface types inside a parameter profile
8285 -- (Obj_Param : in out Iface; ...; Param : Iface)
8287 -- If the interface type is implemented, then the matching type
8288 -- in the primitive should be the implementing record type.
8290 if Ekind (Iface_Typ) = E_Record_Type
8291 and then Is_Interface (Iface_Typ)
8292 and then Is_Implemented (Ifaces_List, Iface_Typ)
8294 if Prim_Typ /= Typ then
8298 -- The two parameters must be both mode and subtype conformant
8300 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
8302 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
8311 -- One of the two lists contains more parameters than the other
8313 if Present (Iface_Param) or else Present (Prim_Param) then
8318 end Matches_Prefixed_View_Profile;
8320 -- Start of processing for Check_Synchronized_Overriding
8323 Overridden_Subp := Empty;
8325 -- Def_Id must be an entry or a subprogram. We should skip predefined
8326 -- primitives internally generated by the frontend; however at this
8327 -- stage predefined primitives are still not fully decorated. As a
8328 -- minor optimization we skip here internally generated subprograms.
8330 if (Ekind (Def_Id) /= E_Entry
8331 and then Ekind (Def_Id) /= E_Function
8332 and then Ekind (Def_Id) /= E_Procedure)
8333 or else not Comes_From_Source (Def_Id)
8338 -- Search for the concurrent declaration since it contains the list
8339 -- of all implemented interfaces. In this case, the subprogram is
8340 -- declared within the scope of a protected or a task type.
8342 if Present (Scope (Def_Id))
8343 and then Is_Concurrent_Type (Scope (Def_Id))
8344 and then not Is_Generic_Actual_Type (Scope (Def_Id))
8346 Typ := Scope (Def_Id);
8349 -- The enclosing scope is not a synchronized type and the subprogram
8352 elsif No (First_Formal (Def_Id)) then
8355 -- The subprogram has formals and hence it may be a primitive of a
8359 Typ := Etype (First_Formal (Def_Id));
8361 if Is_Access_Type (Typ) then
8362 Typ := Directly_Designated_Type (Typ);
8365 if Is_Concurrent_Type (Typ)
8366 and then not Is_Generic_Actual_Type (Typ)
8370 -- This case occurs when the concurrent type is declared within
8371 -- a generic unit. As a result the corresponding record has been
8372 -- built and used as the type of the first formal, we just have
8373 -- to retrieve the corresponding concurrent type.
8375 elsif Is_Concurrent_Record_Type (Typ)
8376 and then not Is_Class_Wide_Type (Typ)
8377 and then Present (Corresponding_Concurrent_Type (Typ))
8379 Typ := Corresponding_Concurrent_Type (Typ);
8387 -- There is no overriding to check if is an inherited operation in a
8388 -- type derivation on for a generic actual.
8390 Collect_Interfaces (Typ, Ifaces_List);
8392 if Is_Empty_Elmt_List (Ifaces_List) then
8396 -- Determine whether entry or subprogram Def_Id overrides a primitive
8397 -- operation that belongs to one of the interfaces in Ifaces_List.
8400 Candidate : Entity_Id := Empty;
8401 Hom : Entity_Id := Empty;
8402 Iface_Typ : Entity_Id;
8403 Subp : Entity_Id := Empty;
8406 -- Traverse the homonym chain, looking for a potentially
8407 -- overridden subprogram that belongs to an implemented
8410 Hom := Current_Entity_In_Scope (Def_Id);
8411 while Present (Hom) loop
8415 or else not Is_Overloadable (Subp)
8416 or else not Is_Primitive (Subp)
8417 or else not Is_Dispatching_Operation (Subp)
8418 or else not Present (Find_Dispatching_Type (Subp))
8419 or else not Is_Interface (Find_Dispatching_Type (Subp))
8423 -- Entries and procedures can override abstract or null
8424 -- interface procedures.
8426 elsif (Ekind (Def_Id) = E_Procedure
8427 or else Ekind (Def_Id) = E_Entry)
8428 and then Ekind (Subp) = E_Procedure
8429 and then Matches_Prefixed_View_Profile
8430 (Parameter_Specifications (Parent (Def_Id)),
8431 Parameter_Specifications (Parent (Subp)))
8435 -- For an overridden subprogram Subp, check whether the mode
8436 -- of its first parameter is correct depending on the kind
8437 -- of synchronized type.
8440 Formal : constant Node_Id := First_Formal (Candidate);
8443 -- In order for an entry or a protected procedure to
8444 -- override, the first parameter of the overridden
8445 -- routine must be of mode "out", "in out" or
8446 -- access-to-variable.
8448 if (Ekind (Candidate) = E_Entry
8449 or else Ekind (Candidate) = E_Procedure)
8450 and then Is_Protected_Type (Typ)
8451 and then Ekind (Formal) /= E_In_Out_Parameter
8452 and then Ekind (Formal) /= E_Out_Parameter
8453 and then Nkind (Parameter_Type (Parent (Formal)))
8454 /= N_Access_Definition
8458 -- All other cases are OK since a task entry or routine
8459 -- does not have a restriction on the mode of the first
8460 -- parameter of the overridden interface routine.
8463 Overridden_Subp := Candidate;
8468 -- Functions can override abstract interface functions
8470 elsif Ekind (Def_Id) = E_Function
8471 and then Ekind (Subp) = E_Function
8472 and then Matches_Prefixed_View_Profile
8473 (Parameter_Specifications (Parent (Def_Id)),
8474 Parameter_Specifications (Parent (Subp)))
8475 and then Etype (Result_Definition (Parent (Def_Id))) =
8476 Etype (Result_Definition (Parent (Subp)))
8478 Overridden_Subp := Subp;
8482 Hom := Homonym (Hom);
8485 -- After examining all candidates for overriding, we are left with
8486 -- the best match which is a mode incompatible interface routine.
8487 -- Do not emit an error if the Expander is active since this error
8488 -- will be detected later on after all concurrent types are
8489 -- expanded and all wrappers are built. This check is meant for
8490 -- spec-only compilations.
8492 if Present (Candidate) and then not Expander_Active then
8494 Find_Parameter_Type (Parent (First_Formal (Candidate)));
8496 -- Def_Id is primitive of a protected type, declared inside the
8497 -- type, and the candidate is primitive of a limited or
8498 -- synchronized interface.
8501 and then Is_Protected_Type (Typ)
8503 (Is_Limited_Interface (Iface_Typ)
8504 or else Is_Protected_Interface (Iface_Typ)
8505 or else Is_Synchronized_Interface (Iface_Typ)
8506 or else Is_Task_Interface (Iface_Typ))
8508 Error_Msg_PT (Parent (Typ), Candidate);
8512 Overridden_Subp := Candidate;
8515 end Check_Synchronized_Overriding;
8517 ----------------------------
8518 -- Is_Private_Declaration --
8519 ----------------------------
8521 function Is_Private_Declaration (E : Entity_Id) return Boolean is
8522 Priv_Decls : List_Id;
8523 Decl : constant Node_Id := Unit_Declaration_Node (E);
8526 if Is_Package_Or_Generic_Package (Current_Scope)
8527 and then In_Private_Part (Current_Scope)
8530 Private_Declarations (
8531 Specification (Unit_Declaration_Node (Current_Scope)));
8533 return In_Package_Body (Current_Scope)
8535 (Is_List_Member (Decl)
8536 and then List_Containing (Decl) = Priv_Decls)
8537 or else (Nkind (Parent (Decl)) = N_Package_Specification
8540 (Defining_Entity (Parent (Decl)))
8541 and then List_Containing (Parent (Parent (Decl)))
8546 end Is_Private_Declaration;
8548 --------------------------
8549 -- Is_Overriding_Alias --
8550 --------------------------
8552 function Is_Overriding_Alias
8554 New_E : Entity_Id) return Boolean
8556 AO : constant Entity_Id := Alias (Old_E);
8557 AN : constant Entity_Id := Alias (New_E);
8560 return Scope (AO) /= Scope (AN)
8561 or else No (DTC_Entity (AO))
8562 or else No (DTC_Entity (AN))
8563 or else DT_Position (AO) = DT_Position (AN);
8564 end Is_Overriding_Alias;
8566 -- Start of processing for New_Overloaded_Entity
8569 -- We need to look for an entity that S may override. This must be a
8570 -- homonym in the current scope, so we look for the first homonym of
8571 -- S in the current scope as the starting point for the search.
8573 E := Current_Entity_In_Scope (S);
8575 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
8576 -- They are directly added to the list of primitive operations of
8577 -- Derived_Type, unless this is a rederivation in the private part
8578 -- of an operation that was already derived in the visible part of
8579 -- the current package.
8581 if Ada_Version >= Ada_2005
8582 and then Present (Derived_Type)
8583 and then Present (Alias (S))
8584 and then Is_Dispatching_Operation (Alias (S))
8585 and then Present (Find_Dispatching_Type (Alias (S)))
8586 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
8588 -- For private types, when the full-view is processed we propagate to
8589 -- the full view the non-overridden entities whose attribute "alias"
8590 -- references an interface primitive. These entities were added by
8591 -- Derive_Subprograms to ensure that interface primitives are
8594 -- Inside_Freeze_Actions is non zero when S corresponds with an
8595 -- internal entity that links an interface primitive with its
8596 -- covering primitive through attribute Interface_Alias (see
8597 -- Add_Internal_Interface_Entities).
8599 if Inside_Freezing_Actions = 0
8600 and then Is_Package_Or_Generic_Package (Current_Scope)
8601 and then In_Private_Part (Current_Scope)
8602 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
8603 and then Nkind (Parent (S)) = N_Full_Type_Declaration
8604 and then Full_View (Defining_Identifier (Parent (E)))
8605 = Defining_Identifier (Parent (S))
8606 and then Alias (E) = Alias (S)
8608 Check_Operation_From_Private_View (S, E);
8609 Set_Is_Dispatching_Operation (S);
8614 Enter_Overloaded_Entity (S);
8615 Check_Dispatching_Operation (S, Empty);
8616 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8622 -- If there is no homonym then this is definitely not overriding
8625 Enter_Overloaded_Entity (S);
8626 Check_Dispatching_Operation (S, Empty);
8627 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8629 -- If subprogram has an explicit declaration, check whether it
8630 -- has an overriding indicator.
8632 if Comes_From_Source (S) then
8633 Check_Synchronized_Overriding (S, Overridden_Subp);
8635 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
8636 -- it may have overridden some hidden inherited primitive. Update
8637 -- Overridden_Subp to avoid spurious errors when checking the
8638 -- overriding indicator.
8640 if Ada_Version >= Ada_2012
8641 and then No (Overridden_Subp)
8642 and then Is_Dispatching_Operation (S)
8643 and then Present (Overridden_Operation (S))
8645 Overridden_Subp := Overridden_Operation (S);
8648 Check_Overriding_Indicator
8649 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8652 -- If there is a homonym that is not overloadable, then we have an
8653 -- error, except for the special cases checked explicitly below.
8655 elsif not Is_Overloadable (E) then
8657 -- Check for spurious conflict produced by a subprogram that has the
8658 -- same name as that of the enclosing generic package. The conflict
8659 -- occurs within an instance, between the subprogram and the renaming
8660 -- declaration for the package. After the subprogram, the package
8661 -- renaming declaration becomes hidden.
8663 if Ekind (E) = E_Package
8664 and then Present (Renamed_Object (E))
8665 and then Renamed_Object (E) = Current_Scope
8666 and then Nkind (Parent (Renamed_Object (E))) =
8667 N_Package_Specification
8668 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
8671 Set_Is_Immediately_Visible (E, False);
8672 Enter_Overloaded_Entity (S);
8673 Set_Homonym (S, Homonym (E));
8674 Check_Dispatching_Operation (S, Empty);
8675 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
8677 -- If the subprogram is implicit it is hidden by the previous
8678 -- declaration. However if it is dispatching, it must appear in the
8679 -- dispatch table anyway, because it can be dispatched to even if it
8680 -- cannot be called directly.
8682 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
8683 Set_Scope (S, Current_Scope);
8685 if Is_Dispatching_Operation (Alias (S)) then
8686 Check_Dispatching_Operation (S, Empty);
8692 Error_Msg_Sloc := Sloc (E);
8694 -- Generate message, with useful additional warning if in generic
8696 if Is_Generic_Unit (E) then
8697 Error_Msg_N ("previous generic unit cannot be overloaded", S);
8698 Error_Msg_N ("\& conflicts with declaration#", S);
8700 Error_Msg_N ("& conflicts with declaration#", S);
8706 -- E exists and is overloadable
8709 Check_Synchronized_Overriding (S, Overridden_Subp);
8711 -- Loop through E and its homonyms to determine if any of them is
8712 -- the candidate for overriding by S.
8714 while Present (E) loop
8716 -- Definitely not interesting if not in the current scope
8718 if Scope (E) /= Current_Scope then
8721 -- Ada 2012 (AI05-0165): For internally generated bodies of
8722 -- null procedures locate the internally generated spec. We
8723 -- enforce mode conformance since a tagged type may inherit
8724 -- from interfaces several null primitives which differ only
8725 -- in the mode of the formals.
8727 elsif not Comes_From_Source (S)
8728 and then Is_Null_Procedure (S)
8729 and then not Mode_Conformant (E, S)
8733 -- Check if we have type conformance
8735 elsif Type_Conformant (E, S) then
8737 -- If the old and new entities have the same profile and one
8738 -- is not the body of the other, then this is an error, unless
8739 -- one of them is implicitly declared.
8741 -- There are some cases when both can be implicit, for example
8742 -- when both a literal and a function that overrides it are
8743 -- inherited in a derivation, or when an inherited operation
8744 -- of a tagged full type overrides the inherited operation of
8745 -- a private extension. Ada 83 had a special rule for the
8746 -- literal case. In Ada 95, the later implicit operation hides
8747 -- the former, and the literal is always the former. In the
8748 -- odd case where both are derived operations declared at the
8749 -- same point, both operations should be declared, and in that
8750 -- case we bypass the following test and proceed to the next
8751 -- part. This can only occur for certain obscure cases in
8752 -- instances, when an operation on a type derived from a formal
8753 -- private type does not override a homograph inherited from
8754 -- the actual. In subsequent derivations of such a type, the
8755 -- DT positions of these operations remain distinct, if they
8758 if Present (Alias (S))
8759 and then (No (Alias (E))
8760 or else Comes_From_Source (E)
8761 or else Is_Abstract_Subprogram (S)
8763 (Is_Dispatching_Operation (E)
8764 and then Is_Overriding_Alias (E, S)))
8765 and then Ekind (E) /= E_Enumeration_Literal
8767 -- When an derived operation is overloaded it may be due to
8768 -- the fact that the full view of a private extension
8769 -- re-inherits. It has to be dealt with.
8771 if Is_Package_Or_Generic_Package (Current_Scope)
8772 and then In_Private_Part (Current_Scope)
8774 Check_Operation_From_Private_View (S, E);
8777 -- In any case the implicit operation remains hidden by the
8778 -- existing declaration, which is overriding. Indicate that
8779 -- E overrides the operation from which S is inherited.
8781 if Present (Alias (S)) then
8782 Set_Overridden_Operation (E, Alias (S));
8784 Set_Overridden_Operation (E, S);
8787 if Comes_From_Source (E) then
8788 Check_Overriding_Indicator (E, S, Is_Primitive => False);
8793 -- Within an instance, the renaming declarations for actual
8794 -- subprograms may become ambiguous, but they do not hide each
8797 elsif Ekind (E) /= E_Entry
8798 and then not Comes_From_Source (E)
8799 and then not Is_Generic_Instance (E)
8800 and then (Present (Alias (E))
8801 or else Is_Intrinsic_Subprogram (E))
8802 and then (not In_Instance
8803 or else No (Parent (E))
8804 or else Nkind (Unit_Declaration_Node (E)) /=
8805 N_Subprogram_Renaming_Declaration)
8807 -- A subprogram child unit is not allowed to override an
8808 -- inherited subprogram (10.1.1(20)).
8810 if Is_Child_Unit (S) then
8812 ("child unit overrides inherited subprogram in parent",
8817 if Is_Non_Overriding_Operation (E, S) then
8818 Enter_Overloaded_Entity (S);
8820 if No (Derived_Type)
8821 or else Is_Tagged_Type (Derived_Type)
8823 Check_Dispatching_Operation (S, Empty);
8829 -- E is a derived operation or an internal operator which
8830 -- is being overridden. Remove E from further visibility.
8831 -- Furthermore, if E is a dispatching operation, it must be
8832 -- replaced in the list of primitive operations of its type
8833 -- (see Override_Dispatching_Operation).
8835 Overridden_Subp := E;
8841 Prev := First_Entity (Current_Scope);
8842 while Present (Prev)
8843 and then Next_Entity (Prev) /= E
8848 -- It is possible for E to be in the current scope and
8849 -- yet not in the entity chain. This can only occur in a
8850 -- generic context where E is an implicit concatenation
8851 -- in the formal part, because in a generic body the
8852 -- entity chain starts with the formals.
8855 (Present (Prev) or else Chars (E) = Name_Op_Concat);
8857 -- E must be removed both from the entity_list of the
8858 -- current scope, and from the visibility chain
8860 if Debug_Flag_E then
8861 Write_Str ("Override implicit operation ");
8862 Write_Int (Int (E));
8866 -- If E is a predefined concatenation, it stands for four
8867 -- different operations. As a result, a single explicit
8868 -- declaration does not hide it. In a possible ambiguous
8869 -- situation, Disambiguate chooses the user-defined op,
8870 -- so it is correct to retain the previous internal one.
8872 if Chars (E) /= Name_Op_Concat
8873 or else Ekind (E) /= E_Operator
8875 -- For nondispatching derived operations that are
8876 -- overridden by a subprogram declared in the private
8877 -- part of a package, we retain the derived subprogram
8878 -- but mark it as not immediately visible. If the
8879 -- derived operation was declared in the visible part
8880 -- then this ensures that it will still be visible
8881 -- outside the package with the proper signature
8882 -- (calls from outside must also be directed to this
8883 -- version rather than the overriding one, unlike the
8884 -- dispatching case). Calls from inside the package
8885 -- will still resolve to the overriding subprogram
8886 -- since the derived one is marked as not visible
8887 -- within the package.
8889 -- If the private operation is dispatching, we achieve
8890 -- the overriding by keeping the implicit operation
8891 -- but setting its alias to be the overriding one. In
8892 -- this fashion the proper body is executed in all
8893 -- cases, but the original signature is used outside
8896 -- If the overriding is not in the private part, we
8897 -- remove the implicit operation altogether.
8899 if Is_Private_Declaration (S) then
8900 if not Is_Dispatching_Operation (E) then
8901 Set_Is_Immediately_Visible (E, False);
8903 -- Work done in Override_Dispatching_Operation,
8904 -- so nothing else need to be done here.
8910 -- Find predecessor of E in Homonym chain
8912 if E = Current_Entity (E) then
8915 Prev_Vis := Current_Entity (E);
8916 while Homonym (Prev_Vis) /= E loop
8917 Prev_Vis := Homonym (Prev_Vis);
8921 if Prev_Vis /= Empty then
8923 -- Skip E in the visibility chain
8925 Set_Homonym (Prev_Vis, Homonym (E));
8928 Set_Name_Entity_Id (Chars (E), Homonym (E));
8931 Set_Next_Entity (Prev, Next_Entity (E));
8933 if No (Next_Entity (Prev)) then
8934 Set_Last_Entity (Current_Scope, Prev);
8939 Enter_Overloaded_Entity (S);
8941 -- For entities generated by Derive_Subprograms the
8942 -- overridden operation is the inherited primitive
8943 -- (which is available through the attribute alias).
8945 if not (Comes_From_Source (E))
8946 and then Is_Dispatching_Operation (E)
8947 and then Find_Dispatching_Type (E) =
8948 Find_Dispatching_Type (S)
8949 and then Present (Alias (E))
8950 and then Comes_From_Source (Alias (E))
8952 Set_Overridden_Operation (S, Alias (E));
8954 -- Normal case of setting entity as overridden
8956 -- Note: Static_Initialization and Overridden_Operation
8957 -- attributes use the same field in subprogram entities.
8958 -- Static_Initialization is only defined for internal
8959 -- initialization procedures, where Overridden_Operation
8960 -- is irrelevant. Therefore the setting of this attribute
8961 -- must check whether the target is an init_proc.
8963 elsif not Is_Init_Proc (S) then
8964 Set_Overridden_Operation (S, E);
8967 Check_Overriding_Indicator (S, E, Is_Primitive => True);
8969 -- If S is a user-defined subprogram or a null procedure
8970 -- expanded to override an inherited null procedure, or a
8971 -- predefined dispatching primitive then indicate that E
8972 -- overrides the operation from which S is inherited.
8974 if Comes_From_Source (S)
8976 (Present (Parent (S))
8978 Nkind (Parent (S)) = N_Procedure_Specification
8980 Null_Present (Parent (S)))
8982 (Present (Alias (E))
8984 Is_Predefined_Dispatching_Operation (Alias (E)))
8986 if Present (Alias (E)) then
8987 Set_Overridden_Operation (S, Alias (E));
8991 if Is_Dispatching_Operation (E) then
8993 -- An overriding dispatching subprogram inherits the
8994 -- convention of the overridden subprogram (AI-117).
8996 Set_Convention (S, Convention (E));
8997 Check_Dispatching_Operation (S, E);
9000 Check_Dispatching_Operation (S, Empty);
9003 Check_For_Primitive_Subprogram
9004 (Is_Primitive_Subp, Is_Overriding => True);
9005 goto Check_Inequality;
9008 -- Apparent redeclarations in instances can occur when two
9009 -- formal types get the same actual type. The subprograms in
9010 -- in the instance are legal, even if not callable from the
9011 -- outside. Calls from within are disambiguated elsewhere.
9012 -- For dispatching operations in the visible part, the usual
9013 -- rules apply, and operations with the same profile are not
9016 elsif (In_Instance_Visible_Part
9017 and then not Is_Dispatching_Operation (E))
9018 or else In_Instance_Not_Visible
9022 -- Here we have a real error (identical profile)
9025 Error_Msg_Sloc := Sloc (E);
9027 -- Avoid cascaded errors if the entity appears in
9028 -- subsequent calls.
9030 Set_Scope (S, Current_Scope);
9032 -- Generate error, with extra useful warning for the case
9033 -- of a generic instance with no completion.
9035 if Is_Generic_Instance (S)
9036 and then not Has_Completion (E)
9039 ("instantiation cannot provide body for&", S);
9040 Error_Msg_N ("\& conflicts with declaration#", S);
9042 Error_Msg_N ("& conflicts with declaration#", S);
9049 -- If one subprogram has an access parameter and the other
9050 -- a parameter of an access type, calls to either might be
9051 -- ambiguous. Verify that parameters match except for the
9052 -- access parameter.
9054 if May_Hide_Profile then
9060 F1 := First_Formal (S);
9061 F2 := First_Formal (E);
9062 while Present (F1) and then Present (F2) loop
9063 if Is_Access_Type (Etype (F1)) then
9064 if not Is_Access_Type (Etype (F2))
9065 or else not Conforming_Types
9066 (Designated_Type (Etype (F1)),
9067 Designated_Type (Etype (F2)),
9070 May_Hide_Profile := False;
9074 not Conforming_Types
9075 (Etype (F1), Etype (F2), Type_Conformant)
9077 May_Hide_Profile := False;
9088 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
9097 -- On exit, we know that S is a new entity
9099 Enter_Overloaded_Entity (S);
9100 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
9101 Check_Overriding_Indicator
9102 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
9104 -- Overloading is not allowed in SPARK, except for operators
9106 if Nkind (S) /= N_Defining_Operator_Symbol then
9107 Error_Msg_Sloc := Sloc (Homonym (S));
9108 Check_SPARK_Restriction
9109 ("overloading not allowed with entity#", S);
9112 -- If S is a derived operation for an untagged type then by
9113 -- definition it's not a dispatching operation (even if the parent
9114 -- operation was dispatching), so Check_Dispatching_Operation is not
9115 -- called in that case.
9117 if No (Derived_Type)
9118 or else Is_Tagged_Type (Derived_Type)
9120 Check_Dispatching_Operation (S, Empty);
9124 -- If this is a user-defined equality operator that is not a derived
9125 -- subprogram, create the corresponding inequality. If the operation is
9126 -- dispatching, the expansion is done elsewhere, and we do not create
9127 -- an explicit inequality operation.
9129 <<Check_Inequality>>
9130 if Chars (S) = Name_Op_Eq
9131 and then Etype (S) = Standard_Boolean
9132 and then Present (Parent (S))
9133 and then not Is_Dispatching_Operation (S)
9135 Make_Inequality_Operator (S);
9137 if Ada_Version >= Ada_2012 then
9138 Check_Untagged_Equality (S);
9141 end New_Overloaded_Entity;
9143 ---------------------
9144 -- Process_Formals --
9145 ---------------------
9147 procedure Process_Formals
9149 Related_Nod : Node_Id)
9151 Param_Spec : Node_Id;
9153 Formal_Type : Entity_Id;
9157 Num_Out_Params : Nat := 0;
9158 First_Out_Param : Entity_Id := Empty;
9159 -- Used for setting Is_Only_Out_Parameter
9161 function Designates_From_With_Type (Typ : Entity_Id) return Boolean;
9162 -- Determine whether an access type designates a type coming from a
9165 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
9166 -- Check whether the default has a class-wide type. After analysis the
9167 -- default has the type of the formal, so we must also check explicitly
9168 -- for an access attribute.
9170 -------------------------------
9171 -- Designates_From_With_Type --
9172 -------------------------------
9174 function Designates_From_With_Type (Typ : Entity_Id) return Boolean is
9175 Desig : Entity_Id := Typ;
9178 if Is_Access_Type (Desig) then
9179 Desig := Directly_Designated_Type (Desig);
9182 if Is_Class_Wide_Type (Desig) then
9183 Desig := Root_Type (Desig);
9187 Ekind (Desig) = E_Incomplete_Type
9188 and then From_With_Type (Desig);
9189 end Designates_From_With_Type;
9191 ---------------------------
9192 -- Is_Class_Wide_Default --
9193 ---------------------------
9195 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
9197 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
9198 or else (Nkind (D) = N_Attribute_Reference
9199 and then Attribute_Name (D) = Name_Access
9200 and then Is_Class_Wide_Type (Etype (Prefix (D))));
9201 end Is_Class_Wide_Default;
9203 -- Start of processing for Process_Formals
9206 -- In order to prevent premature use of the formals in the same formal
9207 -- part, the Ekind is left undefined until all default expressions are
9208 -- analyzed. The Ekind is established in a separate loop at the end.
9210 Param_Spec := First (T);
9211 while Present (Param_Spec) loop
9212 Formal := Defining_Identifier (Param_Spec);
9213 Set_Never_Set_In_Source (Formal, True);
9214 Enter_Name (Formal);
9216 -- Case of ordinary parameters
9218 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
9219 Find_Type (Parameter_Type (Param_Spec));
9220 Ptype := Parameter_Type (Param_Spec);
9222 if Ptype = Error then
9226 Formal_Type := Entity (Ptype);
9228 if Is_Incomplete_Type (Formal_Type)
9230 (Is_Class_Wide_Type (Formal_Type)
9231 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
9233 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
9234 -- primitive operations, as long as their completion is
9235 -- in the same declarative part. If in the private part
9236 -- this means that the type cannot be a Taft-amendment type.
9237 -- Check is done on package exit. For access to subprograms,
9238 -- the use is legal for Taft-amendment types.
9240 if Is_Tagged_Type (Formal_Type) then
9241 if Ekind (Scope (Current_Scope)) = E_Package
9242 and then not From_With_Type (Formal_Type)
9243 and then not Is_Class_Wide_Type (Formal_Type)
9246 (Parent (T), N_Access_Function_Definition,
9247 N_Access_Procedure_Definition)
9251 Private_Dependents (Base_Type (Formal_Type)));
9253 -- Freezing is delayed to ensure that Register_Prim
9254 -- will get called for this operation, which is needed
9255 -- in cases where static dispatch tables aren't built.
9256 -- (Note that the same is done for controlling access
9257 -- parameter cases in function Access_Definition.)
9259 Set_Has_Delayed_Freeze (Current_Scope);
9263 -- Special handling of Value_Type for CIL case
9265 elsif Is_Value_Type (Formal_Type) then
9268 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
9269 N_Access_Procedure_Definition)
9271 -- AI05-0151: Tagged incomplete types are allowed in all
9272 -- formal parts. Untagged incomplete types are not allowed
9275 if Ada_Version >= Ada_2012 then
9276 if Is_Tagged_Type (Formal_Type) then
9279 elsif Nkind_In (Parent (Parent (T)), N_Accept_Statement,
9284 ("invalid use of untagged incomplete type&",
9285 Ptype, Formal_Type);
9290 ("invalid use of incomplete type&",
9291 Param_Spec, Formal_Type);
9293 -- Further checks on the legality of incomplete types
9294 -- in formal parts are delayed until the freeze point
9295 -- of the enclosing subprogram or access to subprogram.
9299 elsif Ekind (Formal_Type) = E_Void then
9301 ("premature use of&",
9302 Parameter_Type (Param_Spec), Formal_Type);
9305 -- Ada 2012 (AI-142): Handle aliased parameters
9307 if Ada_Version >= Ada_2012
9308 and then Aliased_Present (Param_Spec)
9310 Set_Is_Aliased (Formal);
9313 -- Ada 2005 (AI-231): Create and decorate an internal subtype
9314 -- declaration corresponding to the null-excluding type of the
9315 -- formal in the enclosing scope. Finally, replace the parameter
9316 -- type of the formal with the internal subtype.
9318 if Ada_Version >= Ada_2005
9319 and then Null_Exclusion_Present (Param_Spec)
9321 if not Is_Access_Type (Formal_Type) then
9323 ("`NOT NULL` allowed only for an access type", Param_Spec);
9326 if Can_Never_Be_Null (Formal_Type)
9327 and then Comes_From_Source (Related_Nod)
9330 ("`NOT NULL` not allowed (& already excludes null)",
9331 Param_Spec, Formal_Type);
9335 Create_Null_Excluding_Itype
9337 Related_Nod => Related_Nod,
9338 Scope_Id => Scope (Current_Scope));
9340 -- If the designated type of the itype is an itype we
9341 -- decorate it with the Has_Delayed_Freeze attribute to
9342 -- avoid problems with the backend.
9345 -- type T is access procedure;
9346 -- procedure Op (O : not null T);
9348 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
9349 Set_Has_Delayed_Freeze (Formal_Type);
9354 -- An access formal type
9358 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
9360 -- No need to continue if we already notified errors
9362 if not Present (Formal_Type) then
9366 -- Ada 2005 (AI-254)
9369 AD : constant Node_Id :=
9370 Access_To_Subprogram_Definition
9371 (Parameter_Type (Param_Spec));
9373 if Present (AD) and then Protected_Present (AD) then
9375 Replace_Anonymous_Access_To_Protected_Subprogram
9381 Set_Etype (Formal, Formal_Type);
9383 -- Deal with default expression if present
9385 Default := Expression (Param_Spec);
9387 if Present (Default) then
9388 Check_SPARK_Restriction
9389 ("default expression is not allowed", Default);
9391 if Out_Present (Param_Spec) then
9393 ("default initialization only allowed for IN parameters",
9397 -- Do the special preanalysis of the expression (see section on
9398 -- "Handling of Default Expressions" in the spec of package Sem).
9400 Preanalyze_Spec_Expression (Default, Formal_Type);
9402 -- An access to constant cannot be the default for
9403 -- an access parameter that is an access to variable.
9405 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9406 and then not Is_Access_Constant (Formal_Type)
9407 and then Is_Access_Type (Etype (Default))
9408 and then Is_Access_Constant (Etype (Default))
9411 ("formal that is access to variable cannot be initialized " &
9412 "with an access-to-constant expression", Default);
9415 -- Check that the designated type of an access parameter's default
9416 -- is not a class-wide type unless the parameter's designated type
9417 -- is also class-wide.
9419 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9420 and then not Designates_From_With_Type (Formal_Type)
9421 and then Is_Class_Wide_Default (Default)
9422 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
9425 ("access to class-wide expression not allowed here", Default);
9428 -- Check incorrect use of dynamically tagged expressions
9430 if Is_Tagged_Type (Formal_Type) then
9431 Check_Dynamically_Tagged_Expression
9434 Related_Nod => Default);
9438 -- Ada 2005 (AI-231): Static checks
9440 if Ada_Version >= Ada_2005
9441 and then Is_Access_Type (Etype (Formal))
9442 and then Can_Never_Be_Null (Etype (Formal))
9444 Null_Exclusion_Static_Checks (Param_Spec);
9451 -- If this is the formal part of a function specification, analyze the
9452 -- subtype mark in the context where the formals are visible but not
9453 -- yet usable, and may hide outer homographs.
9455 if Nkind (Related_Nod) = N_Function_Specification then
9456 Analyze_Return_Type (Related_Nod);
9459 -- Now set the kind (mode) of each formal
9461 Param_Spec := First (T);
9462 while Present (Param_Spec) loop
9463 Formal := Defining_Identifier (Param_Spec);
9464 Set_Formal_Mode (Formal);
9466 if Ekind (Formal) = E_In_Parameter then
9467 Set_Default_Value (Formal, Expression (Param_Spec));
9469 if Present (Expression (Param_Spec)) then
9470 Default := Expression (Param_Spec);
9472 if Is_Scalar_Type (Etype (Default)) then
9474 (Parameter_Type (Param_Spec)) /= N_Access_Definition
9476 Formal_Type := Entity (Parameter_Type (Param_Spec));
9479 Formal_Type := Access_Definition
9480 (Related_Nod, Parameter_Type (Param_Spec));
9483 Apply_Scalar_Range_Check (Default, Formal_Type);
9487 elsif Ekind (Formal) = E_Out_Parameter then
9488 Num_Out_Params := Num_Out_Params + 1;
9490 if Num_Out_Params = 1 then
9491 First_Out_Param := Formal;
9494 elsif Ekind (Formal) = E_In_Out_Parameter then
9495 Num_Out_Params := Num_Out_Params + 1;
9498 -- Force call by reference if aliased
9500 if Is_Aliased (Formal) then
9501 Set_Mechanism (Formal, By_Reference);
9507 if Present (First_Out_Param) and then Num_Out_Params = 1 then
9508 Set_Is_Only_Out_Parameter (First_Out_Param);
9510 end Process_Formals;
9516 procedure Process_PPCs
9518 Spec_Id : Entity_Id;
9519 Body_Id : Entity_Id)
9521 Loc : constant Source_Ptr := Sloc (N);
9525 Designator : Entity_Id;
9526 -- Subprogram designator, set from Spec_Id if present, else Body_Id
9528 Precond : Node_Id := Empty;
9529 -- Set non-Empty if we prepend precondition to the declarations. This
9530 -- is used to hook up inherited preconditions (adding the condition
9531 -- expression with OR ELSE, and adding the message).
9533 Inherited_Precond : Node_Id;
9534 -- Precondition inherited from parent subprogram
9536 Inherited : constant Subprogram_List :=
9537 Inherited_Subprograms (Spec_Id);
9538 -- List of subprograms inherited by this subprogram
9540 Plist : List_Id := No_List;
9541 -- List of generated postconditions
9543 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id;
9544 -- Prag contains an analyzed precondition or postcondition pragma. This
9545 -- function copies the pragma, changes it to the corresponding Check
9546 -- pragma and returns the Check pragma as the result. If Pspec is non-
9547 -- empty, this is the case of inheriting a PPC, where we must change
9548 -- references to parameters of the inherited subprogram to point to the
9549 -- corresponding parameters of the current subprogram.
9551 function Invariants_Or_Predicates_Present return Boolean;
9552 -- Determines if any invariants or predicates are present for any OUT
9553 -- or IN OUT parameters of the subprogram, or (for a function) if the
9554 -- return value has an invariant.
9560 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id is
9561 Nam : constant Name_Id := Pragma_Name (Prag);
9566 -- Prepare map if this is the case where we have to map entities of
9567 -- arguments in the overridden subprogram to corresponding entities
9568 -- of the current subprogram.
9579 Map := New_Elmt_List;
9580 PF := First_Formal (Pspec);
9581 CF := First_Formal (Designator);
9582 while Present (PF) loop
9583 Append_Elmt (PF, Map);
9584 Append_Elmt (CF, Map);
9591 -- Now we can copy the tree, doing any required substitutions
9593 CP := New_Copy_Tree (Prag, Map => Map, New_Scope => Current_Scope);
9595 -- Set Analyzed to false, since we want to reanalyze the check
9596 -- procedure. Note that it is only at the outer level that we
9597 -- do this fiddling, for the spec cases, the already preanalyzed
9598 -- parameters are not affected.
9600 Set_Analyzed (CP, False);
9602 -- We also make sure Comes_From_Source is False for the copy
9604 Set_Comes_From_Source (CP, False);
9606 -- For a postcondition pragma within a generic, preserve the pragma
9607 -- for later expansion.
9609 if Nam = Name_Postcondition
9610 and then not Expander_Active
9615 -- Change copy of pragma into corresponding pragma Check
9617 Prepend_To (Pragma_Argument_Associations (CP),
9618 Make_Pragma_Argument_Association (Sloc (Prag),
9619 Expression => Make_Identifier (Loc, Nam)));
9620 Set_Pragma_Identifier (CP, Make_Identifier (Sloc (Prag), Name_Check));
9622 -- If this is inherited case and the current message starts with
9623 -- "failed p", we change it to "failed inherited p...".
9625 if Present (Pspec) then
9627 Msg : constant Node_Id :=
9628 Last (Pragma_Argument_Associations (CP));
9631 if Chars (Msg) = Name_Message then
9632 String_To_Name_Buffer (Strval (Expression (Msg)));
9634 if Name_Buffer (1 .. 8) = "failed p" then
9635 Insert_Str_In_Name_Buffer ("inherited ", 8);
9637 (Expression (Last (Pragma_Argument_Associations (CP))),
9638 String_From_Name_Buffer);
9644 -- Return the check pragma
9649 --------------------------------------
9650 -- Invariants_Or_Predicates_Present --
9651 --------------------------------------
9653 function Invariants_Or_Predicates_Present return Boolean is
9657 -- Check function return result
9659 if Ekind (Designator) /= E_Procedure
9660 and then Has_Invariants (Etype (Designator))
9667 Formal := First_Formal (Designator);
9668 while Present (Formal) loop
9669 if Ekind (Formal) /= E_In_Parameter
9671 (Has_Invariants (Etype (Formal))
9672 or else Present (Predicate_Function (Etype (Formal))))
9677 Next_Formal (Formal);
9681 end Invariants_Or_Predicates_Present;
9683 -- Start of processing for Process_PPCs
9686 -- Capture designator from spec if present, else from body
9688 if Present (Spec_Id) then
9689 Designator := Spec_Id;
9691 Designator := Body_Id;
9694 -- Grab preconditions from spec
9696 if Present (Spec_Id) then
9698 -- Loop through PPC pragmas from spec. Note that preconditions from
9699 -- the body will be analyzed and converted when we scan the body
9700 -- declarations below.
9702 Prag := Spec_PPC_List (Contract (Spec_Id));
9703 while Present (Prag) loop
9704 if Pragma_Name (Prag) = Name_Precondition then
9706 -- For Pre (or Precondition pragma), we simply prepend the
9707 -- pragma to the list of declarations right away so that it
9708 -- will be executed at the start of the procedure. Note that
9709 -- this processing reverses the order of the list, which is
9710 -- what we want since new entries were chained to the head of
9711 -- the list. There can be more than one precondition when we
9712 -- use pragma Precondition.
9714 if not Class_Present (Prag) then
9715 Prepend (Grab_PPC, Declarations (N));
9717 -- For Pre'Class there can only be one pragma, and we save
9718 -- it in Precond for now. We will add inherited Pre'Class
9719 -- stuff before inserting this pragma in the declarations.
9721 Precond := Grab_PPC;
9725 Prag := Next_Pragma (Prag);
9728 -- Now deal with inherited preconditions
9730 for J in Inherited'Range loop
9731 Prag := Spec_PPC_List (Contract (Inherited (J)));
9733 while Present (Prag) loop
9734 if Pragma_Name (Prag) = Name_Precondition
9735 and then Class_Present (Prag)
9737 Inherited_Precond := Grab_PPC (Inherited (J));
9739 -- No precondition so far, so establish this as the first
9741 if No (Precond) then
9742 Precond := Inherited_Precond;
9744 -- Here we already have a precondition, add inherited one
9747 -- Add new precondition to old one using OR ELSE
9750 New_Expr : constant Node_Id :=
9754 (Pragma_Argument_Associations
9755 (Inherited_Precond))));
9756 Old_Expr : constant Node_Id :=
9760 (Pragma_Argument_Associations
9764 if Paren_Count (Old_Expr) = 0 then
9765 Set_Paren_Count (Old_Expr, 1);
9768 if Paren_Count (New_Expr) = 0 then
9769 Set_Paren_Count (New_Expr, 1);
9773 Make_Or_Else (Sloc (Old_Expr),
9774 Left_Opnd => Relocate_Node (Old_Expr),
9775 Right_Opnd => New_Expr));
9778 -- Add new message in the form:
9780 -- failed precondition from bla
9781 -- also failed inherited precondition from bla
9784 -- Skip this if exception locations are suppressed
9786 if not Exception_Locations_Suppressed then
9788 New_Msg : constant Node_Id :=
9791 (Pragma_Argument_Associations
9792 (Inherited_Precond)));
9793 Old_Msg : constant Node_Id :=
9796 (Pragma_Argument_Associations
9799 Start_String (Strval (Old_Msg));
9800 Store_String_Chars (ASCII.LF & " also ");
9801 Store_String_Chars (Strval (New_Msg));
9802 Set_Strval (Old_Msg, End_String);
9808 Prag := Next_Pragma (Prag);
9812 -- If we have built a precondition for Pre'Class (including any
9813 -- Pre'Class aspects inherited from parent subprograms), then we
9814 -- insert this composite precondition at this stage.
9816 if Present (Precond) then
9817 Prepend (Precond, Declarations (N));
9821 -- Build postconditions procedure if needed and prepend the following
9822 -- declaration to the start of the declarations for the subprogram.
9824 -- procedure _postconditions [(_Result : resulttype)] is
9826 -- pragma Check (Postcondition, condition [,message]);
9827 -- pragma Check (Postcondition, condition [,message]);
9829 -- Invariant_Procedure (_Result) ...
9830 -- Invariant_Procedure (Arg1)
9834 -- First we deal with the postconditions in the body
9836 if Is_Non_Empty_List (Declarations (N)) then
9838 -- Loop through declarations
9840 Prag := First (Declarations (N));
9841 while Present (Prag) loop
9842 if Nkind (Prag) = N_Pragma then
9844 -- If pragma, capture if enabled postcondition, else ignore
9846 if Pragma_Name (Prag) = Name_Postcondition
9847 and then Check_Enabled (Name_Postcondition)
9849 if Plist = No_List then
9850 Plist := Empty_List;
9855 -- If expansion is disabled, as in a generic unit, save
9856 -- pragma for later expansion.
9858 if not Expander_Active then
9859 Prepend (Grab_PPC, Declarations (N));
9861 Append (Grab_PPC, Plist);
9867 -- Not a pragma, if comes from source, then end scan
9869 elsif Comes_From_Source (Prag) then
9872 -- Skip stuff not coming from source
9880 -- Now deal with any postconditions from the spec
9882 if Present (Spec_Id) then
9883 Spec_Postconditions : declare
9884 procedure Process_Post_Conditions
9887 -- This processes the Spec_PPC_List from Spec, processing any
9888 -- postconditions from the list. If Class is True, then only
9889 -- postconditions marked with Class_Present are considered.
9890 -- The caller has checked that Spec_PPC_List is non-Empty.
9892 -----------------------------
9893 -- Process_Post_Conditions --
9894 -----------------------------
9896 procedure Process_Post_Conditions
9909 -- Loop through PPC pragmas from spec
9911 Prag := Spec_PPC_List (Contract (Spec));
9913 if Pragma_Name (Prag) = Name_Postcondition
9914 and then (not Class or else Class_Present (Prag))
9916 if Plist = No_List then
9917 Plist := Empty_List;
9920 if not Expander_Active then
9922 (Grab_PPC (Pspec), Declarations (N));
9924 Append (Grab_PPC (Pspec), Plist);
9928 Prag := Next_Pragma (Prag);
9929 exit when No (Prag);
9931 end Process_Post_Conditions;
9933 -- Start of processing for Spec_Postconditions
9936 if Present (Spec_PPC_List (Contract (Spec_Id))) then
9937 Process_Post_Conditions (Spec_Id, Class => False);
9940 -- Process inherited postconditions
9942 for J in Inherited'Range loop
9943 if Present (Spec_PPC_List (Contract (Inherited (J)))) then
9944 Process_Post_Conditions (Inherited (J), Class => True);
9947 end Spec_Postconditions;
9950 -- If we had any postconditions and expansion is enabled, or if the
9951 -- procedure has invariants, then build the _Postconditions procedure.
9953 if (Present (Plist) or else Invariants_Or_Predicates_Present)
9954 and then Expander_Active
9957 Plist := Empty_List;
9960 -- Special processing for function case
9962 if Ekind (Designator) /= E_Procedure then
9964 Rent : constant Entity_Id :=
9965 Make_Defining_Identifier (Loc, Name_uResult);
9966 Ftyp : constant Entity_Id := Etype (Designator);
9969 Set_Etype (Rent, Ftyp);
9971 -- Add argument for return
9975 Make_Parameter_Specification (Loc,
9976 Parameter_Type => New_Occurrence_Of (Ftyp, Loc),
9977 Defining_Identifier => Rent));
9979 -- Add invariant call if returning type with invariants
9981 if Has_Invariants (Etype (Rent))
9982 and then Present (Invariant_Procedure (Etype (Rent)))
9985 Make_Invariant_Call (New_Occurrence_Of (Rent, Loc)));
9989 -- Procedure rather than a function
9995 -- Add invariant calls and predicate calls for parameters. Note that
9996 -- this is done for functions as well, since in Ada 2012 they can
9997 -- have IN OUT args.
10000 Formal : Entity_Id;
10004 Formal := First_Formal (Designator);
10005 while Present (Formal) loop
10006 if Ekind (Formal) /= E_In_Parameter then
10007 Ftype := Etype (Formal);
10009 if Has_Invariants (Ftype)
10010 and then Present (Invariant_Procedure (Ftype))
10013 Make_Invariant_Call
10014 (New_Occurrence_Of (Formal, Loc)));
10017 if Present (Predicate_Function (Ftype)) then
10019 Make_Predicate_Check
10020 (Ftype, New_Occurrence_Of (Formal, Loc)));
10024 Next_Formal (Formal);
10028 -- Build and insert postcondition procedure
10031 Post_Proc : constant Entity_Id :=
10032 Make_Defining_Identifier (Loc,
10033 Chars => Name_uPostconditions);
10034 -- The entity for the _Postconditions procedure
10037 Prepend_To (Declarations (N),
10038 Make_Subprogram_Body (Loc,
10040 Make_Procedure_Specification (Loc,
10041 Defining_Unit_Name => Post_Proc,
10042 Parameter_Specifications => Parms),
10044 Declarations => Empty_List,
10046 Handled_Statement_Sequence =>
10047 Make_Handled_Sequence_Of_Statements (Loc,
10048 Statements => Plist)));
10050 Set_Ekind (Post_Proc, E_Procedure);
10052 -- If this is a procedure, set the Postcondition_Proc attribute on
10053 -- the proper defining entity for the subprogram.
10055 if Ekind (Designator) = E_Procedure then
10056 Set_Postcondition_Proc (Designator, Post_Proc);
10060 Set_Has_Postconditions (Designator);
10064 ----------------------------
10065 -- Reference_Body_Formals --
10066 ----------------------------
10068 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
10073 if Error_Posted (Spec) then
10077 -- Iterate over both lists. They may be of different lengths if the two
10078 -- specs are not conformant.
10080 Fs := First_Formal (Spec);
10081 Fb := First_Formal (Bod);
10082 while Present (Fs) and then Present (Fb) loop
10083 Generate_Reference (Fs, Fb, 'b');
10085 if Style_Check then
10086 Style.Check_Identifier (Fb, Fs);
10089 Set_Spec_Entity (Fb, Fs);
10090 Set_Referenced (Fs, False);
10094 end Reference_Body_Formals;
10096 -------------------------
10097 -- Set_Actual_Subtypes --
10098 -------------------------
10100 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
10102 Formal : Entity_Id;
10104 First_Stmt : Node_Id := Empty;
10105 AS_Needed : Boolean;
10108 -- If this is an empty initialization procedure, no need to create
10109 -- actual subtypes (small optimization).
10111 if Ekind (Subp) = E_Procedure
10112 and then Is_Null_Init_Proc (Subp)
10117 Formal := First_Formal (Subp);
10118 while Present (Formal) loop
10119 T := Etype (Formal);
10121 -- We never need an actual subtype for a constrained formal
10123 if Is_Constrained (T) then
10124 AS_Needed := False;
10126 -- If we have unknown discriminants, then we do not need an actual
10127 -- subtype, or more accurately we cannot figure it out! Note that
10128 -- all class-wide types have unknown discriminants.
10130 elsif Has_Unknown_Discriminants (T) then
10131 AS_Needed := False;
10133 -- At this stage we have an unconstrained type that may need an
10134 -- actual subtype. For sure the actual subtype is needed if we have
10135 -- an unconstrained array type.
10137 elsif Is_Array_Type (T) then
10140 -- The only other case needing an actual subtype is an unconstrained
10141 -- record type which is an IN parameter (we cannot generate actual
10142 -- subtypes for the OUT or IN OUT case, since an assignment can
10143 -- change the discriminant values. However we exclude the case of
10144 -- initialization procedures, since discriminants are handled very
10145 -- specially in this context, see the section entitled "Handling of
10146 -- Discriminants" in Einfo.
10148 -- We also exclude the case of Discrim_SO_Functions (functions used
10149 -- in front end layout mode for size/offset values), since in such
10150 -- functions only discriminants are referenced, and not only are such
10151 -- subtypes not needed, but they cannot always be generated, because
10152 -- of order of elaboration issues.
10154 elsif Is_Record_Type (T)
10155 and then Ekind (Formal) = E_In_Parameter
10156 and then Chars (Formal) /= Name_uInit
10157 and then not Is_Unchecked_Union (T)
10158 and then not Is_Discrim_SO_Function (Subp)
10162 -- All other cases do not need an actual subtype
10165 AS_Needed := False;
10168 -- Generate actual subtypes for unconstrained arrays and
10169 -- unconstrained discriminated records.
10172 if Nkind (N) = N_Accept_Statement then
10174 -- If expansion is active, the formal is replaced by a local
10175 -- variable that renames the corresponding entry of the
10176 -- parameter block, and it is this local variable that may
10177 -- require an actual subtype.
10179 if Full_Expander_Active then
10180 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
10182 Decl := Build_Actual_Subtype (T, Formal);
10185 if Present (Handled_Statement_Sequence (N)) then
10187 First (Statements (Handled_Statement_Sequence (N)));
10188 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
10189 Mark_Rewrite_Insertion (Decl);
10191 -- If the accept statement has no body, there will be no
10192 -- reference to the actuals, so no need to compute actual
10199 Decl := Build_Actual_Subtype (T, Formal);
10200 Prepend (Decl, Declarations (N));
10201 Mark_Rewrite_Insertion (Decl);
10204 -- The declaration uses the bounds of an existing object, and
10205 -- therefore needs no constraint checks.
10207 Analyze (Decl, Suppress => All_Checks);
10209 -- We need to freeze manually the generated type when it is
10210 -- inserted anywhere else than in a declarative part.
10212 if Present (First_Stmt) then
10213 Insert_List_Before_And_Analyze (First_Stmt,
10214 Freeze_Entity (Defining_Identifier (Decl), N));
10217 if Nkind (N) = N_Accept_Statement
10218 and then Full_Expander_Active
10220 Set_Actual_Subtype (Renamed_Object (Formal),
10221 Defining_Identifier (Decl));
10223 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
10227 Next_Formal (Formal);
10229 end Set_Actual_Subtypes;
10231 ---------------------
10232 -- Set_Formal_Mode --
10233 ---------------------
10235 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
10236 Spec : constant Node_Id := Parent (Formal_Id);
10239 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
10240 -- since we ensure that corresponding actuals are always valid at the
10241 -- point of the call.
10243 if Out_Present (Spec) then
10244 if Ekind (Scope (Formal_Id)) = E_Function
10245 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
10247 -- [IN] OUT parameters allowed for functions in Ada 2012
10249 if Ada_Version >= Ada_2012 then
10250 if In_Present (Spec) then
10251 Set_Ekind (Formal_Id, E_In_Out_Parameter);
10253 Set_Ekind (Formal_Id, E_Out_Parameter);
10256 -- But not in earlier versions of Ada
10259 Error_Msg_N ("functions can only have IN parameters", Spec);
10260 Set_Ekind (Formal_Id, E_In_Parameter);
10263 elsif In_Present (Spec) then
10264 Set_Ekind (Formal_Id, E_In_Out_Parameter);
10267 Set_Ekind (Formal_Id, E_Out_Parameter);
10268 Set_Never_Set_In_Source (Formal_Id, True);
10269 Set_Is_True_Constant (Formal_Id, False);
10270 Set_Current_Value (Formal_Id, Empty);
10274 Set_Ekind (Formal_Id, E_In_Parameter);
10277 -- Set Is_Known_Non_Null for access parameters since the language
10278 -- guarantees that access parameters are always non-null. We also set
10279 -- Can_Never_Be_Null, since there is no way to change the value.
10281 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
10283 -- Ada 2005 (AI-231): In Ada 95, access parameters are always non-
10284 -- null; In Ada 2005, only if then null_exclusion is explicit.
10286 if Ada_Version < Ada_2005
10287 or else Can_Never_Be_Null (Etype (Formal_Id))
10289 Set_Is_Known_Non_Null (Formal_Id);
10290 Set_Can_Never_Be_Null (Formal_Id);
10293 -- Ada 2005 (AI-231): Null-exclusion access subtype
10295 elsif Is_Access_Type (Etype (Formal_Id))
10296 and then Can_Never_Be_Null (Etype (Formal_Id))
10298 Set_Is_Known_Non_Null (Formal_Id);
10300 -- We can also set Can_Never_Be_Null (thus preventing some junk
10301 -- access checks) for the case of an IN parameter, which cannot
10302 -- be changed, or for an IN OUT parameter, which can be changed but
10303 -- not to a null value. But for an OUT parameter, the initial value
10304 -- passed in can be null, so we can't set this flag in that case.
10306 if Ekind (Formal_Id) /= E_Out_Parameter then
10307 Set_Can_Never_Be_Null (Formal_Id);
10311 Set_Mechanism (Formal_Id, Default_Mechanism);
10312 Set_Formal_Validity (Formal_Id);
10313 end Set_Formal_Mode;
10315 -------------------------
10316 -- Set_Formal_Validity --
10317 -------------------------
10319 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
10321 -- If no validity checking, then we cannot assume anything about the
10322 -- validity of parameters, since we do not know there is any checking
10323 -- of the validity on the call side.
10325 if not Validity_Checks_On then
10328 -- If validity checking for parameters is enabled, this means we are
10329 -- not supposed to make any assumptions about argument values.
10331 elsif Validity_Check_Parameters then
10334 -- If we are checking in parameters, we will assume that the caller is
10335 -- also checking parameters, so we can assume the parameter is valid.
10337 elsif Ekind (Formal_Id) = E_In_Parameter
10338 and then Validity_Check_In_Params
10340 Set_Is_Known_Valid (Formal_Id, True);
10342 -- Similar treatment for IN OUT parameters
10344 elsif Ekind (Formal_Id) = E_In_Out_Parameter
10345 and then Validity_Check_In_Out_Params
10347 Set_Is_Known_Valid (Formal_Id, True);
10349 end Set_Formal_Validity;
10351 ------------------------
10352 -- Subtype_Conformant --
10353 ------------------------
10355 function Subtype_Conformant
10356 (New_Id : Entity_Id;
10357 Old_Id : Entity_Id;
10358 Skip_Controlling_Formals : Boolean := False) return Boolean
10362 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
10363 Skip_Controlling_Formals => Skip_Controlling_Formals);
10365 end Subtype_Conformant;
10367 ---------------------
10368 -- Type_Conformant --
10369 ---------------------
10371 function Type_Conformant
10372 (New_Id : Entity_Id;
10373 Old_Id : Entity_Id;
10374 Skip_Controlling_Formals : Boolean := False) return Boolean
10378 May_Hide_Profile := False;
10381 (New_Id, Old_Id, Type_Conformant, False, Result,
10382 Skip_Controlling_Formals => Skip_Controlling_Formals);
10384 end Type_Conformant;
10386 -------------------------------
10387 -- Valid_Operator_Definition --
10388 -------------------------------
10390 procedure Valid_Operator_Definition (Designator : Entity_Id) is
10393 Id : constant Name_Id := Chars (Designator);
10397 F := First_Formal (Designator);
10398 while Present (F) loop
10401 if Present (Default_Value (F)) then
10403 ("default values not allowed for operator parameters",
10410 -- Verify that user-defined operators have proper number of arguments
10411 -- First case of operators which can only be unary
10413 if Id = Name_Op_Not
10414 or else Id = Name_Op_Abs
10418 -- Case of operators which can be unary or binary
10420 elsif Id = Name_Op_Add
10421 or Id = Name_Op_Subtract
10423 N_OK := (N in 1 .. 2);
10425 -- All other operators can only be binary
10433 ("incorrect number of arguments for operator", Designator);
10437 and then Base_Type (Etype (Designator)) = Standard_Boolean
10438 and then not Is_Intrinsic_Subprogram (Designator)
10441 ("explicit definition of inequality not allowed", Designator);
10443 end Valid_Operator_Definition;
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