1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Ch7; use Exp_Ch7;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Lib.Xref; use Lib.Xref;
43 with Layout; use Layout;
44 with Namet; use Namet;
46 with Nlists; use Nlists;
47 with Nmake; use Nmake;
49 with Output; use Output;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Cat; use Sem_Cat;
56 with Sem_Ch3; use Sem_Ch3;
57 with Sem_Ch4; use Sem_Ch4;
58 with Sem_Ch5; use Sem_Ch5;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch10; use Sem_Ch10;
61 with Sem_Ch12; use Sem_Ch12;
62 with Sem_Ch13; use Sem_Ch13;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Prag; use Sem_Prag;
69 with Sem_Res; use Sem_Res;
70 with Sem_Util; use Sem_Util;
71 with Sem_Type; use Sem_Type;
72 with Sem_Warn; use Sem_Warn;
73 with Sinput; use Sinput;
74 with Stand; use Stand;
75 with Sinfo; use Sinfo;
76 with Sinfo.CN; use Sinfo.CN;
77 with Snames; use Snames;
78 with Stringt; use Stringt;
80 with Stylesw; use Stylesw;
81 with Tbuild; use Tbuild;
82 with Uintp; use Uintp;
83 with Urealp; use Urealp;
84 with Validsw; use Validsw;
86 package body Sem_Ch6 is
88 May_Hide_Profile : Boolean := False;
89 -- This flag is used to indicate that two formals in two subprograms being
90 -- checked for conformance differ only in that one is an access parameter
91 -- while the other is of a general access type with the same designated
92 -- type. In this case, if the rest of the signatures match, a call to
93 -- either subprogram may be ambiguous, which is worth a warning. The flag
94 -- is set in Compatible_Types, and the warning emitted in
95 -- New_Overloaded_Entity.
97 -----------------------
98 -- Local Subprograms --
99 -----------------------
101 procedure Analyze_Return_Statement (N : Node_Id);
102 -- Common processing for simple and extended return statements
104 procedure Analyze_Function_Return (N : Node_Id);
105 -- Subsidiary to Analyze_Return_Statement. Called when the return statement
106 -- applies to a [generic] function.
108 procedure Analyze_Return_Type (N : Node_Id);
109 -- Subsidiary to Process_Formals: analyze subtype mark in function
110 -- specification in a context where the formals are visible and hide
113 procedure Analyze_Subprogram_Body_Helper (N : Node_Id);
114 -- Does all the real work of Analyze_Subprogram_Body. This is split out so
115 -- that we can use RETURN but not skip the debug output at the end.
117 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
118 -- Analyze a generic subprogram body. N is the body to be analyzed, and
119 -- Gen_Id is the defining entity Id for the corresponding spec.
121 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id);
122 -- If a subprogram has pragma Inline and inlining is active, use generic
123 -- machinery to build an unexpanded body for the subprogram. This body is
124 -- subsequently used for inline expansions at call sites. If subprogram can
125 -- be inlined (depending on size and nature of local declarations) this
126 -- function returns true. Otherwise subprogram body is treated normally.
127 -- If proper warnings are enabled and the subprogram contains a construct
128 -- that cannot be inlined, the offending construct is flagged accordingly.
130 function Can_Override_Operator (Subp : Entity_Id) return Boolean;
131 -- Returns true if Subp can override a predefined operator.
133 procedure Check_Conformance
136 Ctype : Conformance_Type;
138 Conforms : out Boolean;
139 Err_Loc : Node_Id := Empty;
140 Get_Inst : Boolean := False;
141 Skip_Controlling_Formals : Boolean := False);
142 -- Given two entities, this procedure checks that the profiles associated
143 -- with these entities meet the conformance criterion given by the third
144 -- parameter. If they conform, Conforms is set True and control returns
145 -- to the caller. If they do not conform, Conforms is set to False, and
146 -- in addition, if Errmsg is True on the call, proper messages are output
147 -- to complain about the conformance failure. If Err_Loc is non_Empty
148 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
149 -- error messages are placed on the appropriate part of the construct
150 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
151 -- against a formal access-to-subprogram type so Get_Instance_Of must
154 procedure Check_Subprogram_Order (N : Node_Id);
155 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
156 -- the alpha ordering rule for N if this ordering requirement applicable.
158 procedure Check_Returns
162 Proc : Entity_Id := Empty);
163 -- Called to check for missing return statements in a function body, or for
164 -- returns present in a procedure body which has No_Return set. HSS is the
165 -- handled statement sequence for the subprogram body. This procedure
166 -- checks all flow paths to make sure they either have return (Mode = 'F',
167 -- used for functions) or do not have a return (Mode = 'P', used for
168 -- No_Return procedures). The flag Err is set if there are any control
169 -- paths not explicitly terminated by a return in the function case, and is
170 -- True otherwise. Proc is the entity for the procedure case and is used
171 -- in posting the warning message.
173 procedure Check_Untagged_Equality (Eq_Op : Entity_Id);
174 -- In Ada 2012, a primitive equality operator on an untagged record type
175 -- must appear before the type is frozen, and have the same visibility as
176 -- that of the type. This procedure checks that this rule is met, and
177 -- otherwise emits an error on the subprogram declaration and a warning
178 -- on the earlier freeze point if it is easy to locate.
180 procedure Enter_Overloaded_Entity (S : Entity_Id);
181 -- This procedure makes S, a new overloaded entity, into the first visible
182 -- entity with that name.
184 procedure Install_Entity (E : Entity_Id);
185 -- Make single entity visible (used for generic formals as well)
187 function Is_Non_Overriding_Operation
189 New_E : Entity_Id) return Boolean;
190 -- Enforce the rule given in 12.3(18): a private operation in an instance
191 -- overrides an inherited operation only if the corresponding operation
192 -- was overriding in the generic. This can happen for primitive operations
193 -- of types derived (in the generic unit) from formal private or formal
196 procedure Make_Inequality_Operator (S : Entity_Id);
197 -- Create the declaration for an inequality operator that is implicitly
198 -- created by a user-defined equality operator that yields a boolean.
200 procedure May_Need_Actuals (Fun : Entity_Id);
201 -- Flag functions that can be called without parameters, i.e. those that
202 -- have no parameters, or those for which defaults exist for all parameters
204 procedure Process_PPCs
207 Body_Id : Entity_Id);
208 -- Called from Analyze[_Generic]_Subprogram_Body to deal with scanning post
209 -- conditions for the body and assembling and inserting the _postconditions
210 -- procedure. N is the node for the subprogram body and Body_Id/Spec_Id are
211 -- the entities for the body and separate spec (if there is no separate
212 -- spec, Spec_Id is Empty). Note that invariants and predicates may also
213 -- provide postconditions, and are also handled in this procedure.
215 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
216 -- Formal_Id is an formal parameter entity. This procedure deals with
217 -- setting the proper validity status for this entity, which depends on
218 -- the kind of parameter and the validity checking mode.
220 ---------------------------------------------
221 -- Analyze_Abstract_Subprogram_Declaration --
222 ---------------------------------------------
224 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
225 Designator : constant Entity_Id :=
226 Analyze_Subprogram_Specification (Specification (N));
227 Scop : constant Entity_Id := Current_Scope;
230 Check_SPARK_Restriction ("abstract subprogram is not allowed", N);
232 Generate_Definition (Designator);
233 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
234 Set_Is_Abstract_Subprogram (Designator);
235 New_Overloaded_Entity (Designator);
236 Check_Delayed_Subprogram (Designator);
238 Set_Categorization_From_Scope (Designator, Scop);
240 if Ekind (Scope (Designator)) = E_Protected_Type then
242 ("abstract subprogram not allowed in protected type", N);
244 -- Issue a warning if the abstract subprogram is neither a dispatching
245 -- operation nor an operation that overrides an inherited subprogram or
246 -- predefined operator, since this most likely indicates a mistake.
248 elsif Warn_On_Redundant_Constructs
249 and then not Is_Dispatching_Operation (Designator)
250 and then not Present (Overridden_Operation (Designator))
251 and then (not Is_Operator_Symbol_Name (Chars (Designator))
252 or else Scop /= Scope (Etype (First_Formal (Designator))))
255 ("?abstract subprogram is not dispatching or overriding", N);
258 Generate_Reference_To_Formals (Designator);
259 Check_Eliminated (Designator);
261 if Has_Aspects (N) then
262 Analyze_Aspect_Specifications (N, Designator);
264 end Analyze_Abstract_Subprogram_Declaration;
266 ---------------------------------
267 -- Analyze_Expression_Function --
268 ---------------------------------
270 procedure Analyze_Expression_Function (N : Node_Id) is
271 Loc : constant Source_Ptr := Sloc (N);
272 LocX : constant Source_Ptr := Sloc (Expression (N));
273 Def_Id : constant Entity_Id := Defining_Entity (Specification (N));
277 Prev : constant Entity_Id := Current_Entity_In_Scope (Def_Id);
278 -- If the expression is a completion, Prev is the entity whose
279 -- declaration is completed.
282 -- This is one of the occasions on which we transform the tree during
283 -- semantic analysis. If this is a completion, transform the expression
284 -- function into an equivalent subprogram body, and analyze it.
286 -- Expression functions are inlined unconditionally. The back-end will
287 -- determine whether this is possible.
289 Inline_Processing_Required := True;
292 Make_Subprogram_Body (Loc,
293 Specification => Specification (N),
294 Declarations => Empty_List,
295 Handled_Statement_Sequence =>
296 Make_Handled_Sequence_Of_Statements (LocX,
297 Statements => New_List (
298 Make_Simple_Return_Statement (LocX,
299 Expression => Expression (N)))));
302 and then Ekind (Prev) = E_Generic_Function
304 -- If the expression completes a generic subprogram, we must create a
305 -- separate node for the body, because at instantiation the original
306 -- node of the generic copy must be a generic subprogram body, and
307 -- cannot be a expression function. Otherwise we just rewrite the
308 -- expression with the non-generic body.
310 Insert_After (N, New_Body);
311 Rewrite (N, Make_Null_Statement (Loc));
314 Set_Is_Inlined (Prev);
316 elsif Present (Prev) then
317 Rewrite (N, New_Body);
318 Set_Is_Inlined (Prev);
321 -- If this is not a completion, create both a declaration and a body,
322 -- so that the expression can be inlined whenever possible.
326 Make_Subprogram_Declaration (Loc,
327 Specification => Specification (N));
328 Rewrite (N, New_Decl);
330 Set_Is_Inlined (Defining_Entity (New_Decl));
332 -- Create new set of formals for specification in body.
334 Set_Specification (New_Body,
335 Make_Function_Specification (Loc,
336 Defining_Unit_Name =>
337 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))),
338 Parameter_Specifications =>
339 Copy_Parameter_List (Defining_Entity (New_Decl)),
341 New_Copy_Tree (Result_Definition (Specification (New_Decl)))));
343 Insert_After (N, New_Body);
346 end Analyze_Expression_Function;
348 ----------------------------------------
349 -- Analyze_Extended_Return_Statement --
350 ----------------------------------------
352 procedure Analyze_Extended_Return_Statement (N : Node_Id) is
354 Analyze_Return_Statement (N);
355 end Analyze_Extended_Return_Statement;
357 ----------------------------
358 -- Analyze_Function_Call --
359 ----------------------------
361 procedure Analyze_Function_Call (N : Node_Id) is
362 P : constant Node_Id := Name (N);
363 Actuals : constant List_Id := Parameter_Associations (N);
369 -- A call of the form A.B (X) may be an Ada05 call, which is rewritten
370 -- as B (A, X). If the rewriting is successful, the call has been
371 -- analyzed and we just return.
373 if Nkind (P) = N_Selected_Component
374 and then Name (N) /= P
375 and then Is_Rewrite_Substitution (N)
376 and then Present (Etype (N))
381 -- If error analyzing name, then set Any_Type as result type and return
383 if Etype (P) = Any_Type then
384 Set_Etype (N, Any_Type);
388 -- Otherwise analyze the parameters
390 if Present (Actuals) then
391 Actual := First (Actuals);
392 while Present (Actual) loop
394 Check_Parameterless_Call (Actual);
400 end Analyze_Function_Call;
402 -----------------------------
403 -- Analyze_Function_Return --
404 -----------------------------
406 procedure Analyze_Function_Return (N : Node_Id) is
407 Loc : constant Source_Ptr := Sloc (N);
408 Stm_Entity : constant Entity_Id := Return_Statement_Entity (N);
409 Scope_Id : constant Entity_Id := Return_Applies_To (Stm_Entity);
411 R_Type : constant Entity_Id := Etype (Scope_Id);
412 -- Function result subtype
414 procedure Check_Limited_Return (Expr : Node_Id);
415 -- Check the appropriate (Ada 95 or Ada 2005) rules for returning
416 -- limited types. Used only for simple return statements.
417 -- Expr is the expression returned.
419 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id);
420 -- Check that the return_subtype_indication properly matches the result
421 -- subtype of the function, as required by RM-6.5(5.1/2-5.3/2).
423 --------------------------
424 -- Check_Limited_Return --
425 --------------------------
427 procedure Check_Limited_Return (Expr : Node_Id) is
429 -- Ada 2005 (AI-318-02): Return-by-reference types have been
430 -- removed and replaced by anonymous access results. This is an
431 -- incompatibility with Ada 95. Not clear whether this should be
432 -- enforced yet or perhaps controllable with special switch. ???
434 if Is_Limited_Type (R_Type)
435 and then Comes_From_Source (N)
436 and then not In_Instance_Body
437 and then not OK_For_Limited_Init_In_05 (R_Type, Expr)
441 if Ada_Version >= Ada_2005
442 and then not Debug_Flag_Dot_L
443 and then not GNAT_Mode
446 ("(Ada 2005) cannot copy object of a limited type " &
447 "(RM-2005 6.5(5.5/2))", Expr);
449 if Is_Immutably_Limited_Type (R_Type) then
451 ("\return by reference not permitted in Ada 2005", Expr);
454 -- Warn in Ada 95 mode, to give folks a heads up about this
457 -- In GNAT mode, this is just a warning, to allow it to be
458 -- evilly turned off. Otherwise it is a real error.
460 -- In a generic context, simplify the warning because it makes
461 -- no sense to discuss pass-by-reference or copy.
463 elsif Warn_On_Ada_2005_Compatibility or GNAT_Mode then
464 if Inside_A_Generic then
466 ("return of limited object not permitted in Ada2005 "
467 & "(RM-2005 6.5(5.5/2))?", Expr);
469 elsif Is_Immutably_Limited_Type (R_Type) then
471 ("return by reference not permitted in Ada 2005 "
472 & "(RM-2005 6.5(5.5/2))?", Expr);
475 ("cannot copy object of a limited type in Ada 2005 "
476 & "(RM-2005 6.5(5.5/2))?", Expr);
479 -- Ada 95 mode, compatibility warnings disabled
482 return; -- skip continuation messages below
485 if not Inside_A_Generic then
487 ("\consider switching to return of access type", Expr);
488 Explain_Limited_Type (R_Type, Expr);
491 end Check_Limited_Return;
493 -------------------------------------
494 -- Check_Return_Subtype_Indication --
495 -------------------------------------
497 procedure Check_Return_Subtype_Indication (Obj_Decl : Node_Id) is
498 Return_Obj : constant Node_Id := Defining_Identifier (Obj_Decl);
500 R_Stm_Type : constant Entity_Id := Etype (Return_Obj);
501 -- Subtype given in the extended return statement (must match R_Type)
503 Subtype_Ind : constant Node_Id :=
504 Object_Definition (Original_Node (Obj_Decl));
506 R_Type_Is_Anon_Access :
508 Ekind (R_Type) = E_Anonymous_Access_Subprogram_Type
510 Ekind (R_Type) = E_Anonymous_Access_Protected_Subprogram_Type
512 Ekind (R_Type) = E_Anonymous_Access_Type;
513 -- True if return type of the function is an anonymous access type
514 -- Can't we make Is_Anonymous_Access_Type in einfo ???
516 R_Stm_Type_Is_Anon_Access :
518 Ekind (R_Stm_Type) = E_Anonymous_Access_Subprogram_Type
520 Ekind (R_Stm_Type) = E_Anonymous_Access_Protected_Subprogram_Type
522 Ekind (R_Stm_Type) = E_Anonymous_Access_Type;
523 -- True if type of the return object is an anonymous access type
526 -- First, avoid cascaded errors
528 if Error_Posted (Obj_Decl) or else Error_Posted (Subtype_Ind) then
532 -- "return access T" case; check that the return statement also has
533 -- "access T", and that the subtypes statically match:
534 -- if this is an access to subprogram the signatures must match.
536 if R_Type_Is_Anon_Access then
537 if R_Stm_Type_Is_Anon_Access then
539 Ekind (Designated_Type (R_Stm_Type)) /= E_Subprogram_Type
541 if Base_Type (Designated_Type (R_Stm_Type)) /=
542 Base_Type (Designated_Type (R_Type))
543 or else not Subtypes_Statically_Match (R_Stm_Type, R_Type)
546 ("subtype must statically match function result subtype",
547 Subtype_Mark (Subtype_Ind));
551 -- For two anonymous access to subprogram types, the
552 -- types themselves must be type conformant.
554 if not Conforming_Types
555 (R_Stm_Type, R_Type, Fully_Conformant)
558 ("subtype must statically match function result subtype",
564 Error_Msg_N ("must use anonymous access type", Subtype_Ind);
567 -- If the return object is of an anonymous access type, then report
568 -- an error if the function's result type is not also anonymous.
570 elsif R_Stm_Type_Is_Anon_Access
571 and then not R_Type_Is_Anon_Access
573 Error_Msg_N ("anonymous access not allowed for function with " &
574 "named access result", Subtype_Ind);
576 -- Subtype indication case: check that the return object's type is
577 -- covered by the result type, and that the subtypes statically match
578 -- when the result subtype is constrained. Also handle record types
579 -- with unknown discriminants for which we have built the underlying
580 -- record view. Coverage is needed to allow specific-type return
581 -- objects when the result type is class-wide (see AI05-32).
583 elsif Covers (Base_Type (R_Type), Base_Type (R_Stm_Type))
584 or else (Is_Underlying_Record_View (Base_Type (R_Stm_Type))
588 Underlying_Record_View (Base_Type (R_Stm_Type))))
590 -- A null exclusion may be present on the return type, on the
591 -- function specification, on the object declaration or on the
594 if Is_Access_Type (R_Type)
596 (Can_Never_Be_Null (R_Type)
597 or else Null_Exclusion_Present (Parent (Scope_Id))) /=
598 Can_Never_Be_Null (R_Stm_Type)
601 ("subtype must statically match function result subtype",
605 -- AI05-103: for elementary types, subtypes must statically match
607 if Is_Constrained (R_Type)
608 or else Is_Access_Type (R_Type)
610 if not Subtypes_Statically_Match (R_Stm_Type, R_Type) then
612 ("subtype must statically match function result subtype",
617 elsif Etype (Base_Type (R_Type)) = R_Stm_Type
618 and then Is_Null_Extension (Base_Type (R_Type))
624 ("wrong type for return_subtype_indication", Subtype_Ind);
626 end Check_Return_Subtype_Indication;
628 ---------------------
629 -- Local Variables --
630 ---------------------
634 -- Start of processing for Analyze_Function_Return
637 Set_Return_Present (Scope_Id);
639 if Nkind (N) = N_Simple_Return_Statement then
640 Expr := Expression (N);
642 -- Guard against a malformed expression. The parser may have tried to
643 -- recover but the node is not analyzable.
645 if Nkind (Expr) = N_Error then
646 Set_Etype (Expr, Any_Type);
647 Expander_Mode_Save_And_Set (False);
651 -- The resolution of a controlled [extension] aggregate associated
652 -- with a return statement creates a temporary which needs to be
653 -- finalized on function exit. Wrap the return statement inside a
654 -- block so that the finalization machinery can detect this case.
655 -- This early expansion is done only when the return statement is
656 -- not part of a handled sequence of statements.
658 if Nkind_In (Expr, N_Aggregate,
659 N_Extension_Aggregate)
660 and then Needs_Finalization (R_Type)
661 and then Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
664 Make_Block_Statement (Loc,
665 Handled_Statement_Sequence =>
666 Make_Handled_Sequence_Of_Statements (Loc,
667 Statements => New_List (Relocate_Node (N)))));
673 Analyze_And_Resolve (Expr, R_Type);
674 Check_Limited_Return (Expr);
677 -- RETURN only allowed in SPARK as the last statement in function
679 if Nkind (Parent (N)) /= N_Handled_Sequence_Of_Statements
681 (Nkind (Parent (Parent (N))) /= N_Subprogram_Body
682 or else Present (Next (N)))
684 Check_SPARK_Restriction
685 ("RETURN should be the last statement in function", N);
689 Check_SPARK_Restriction ("extended RETURN is not allowed", N);
691 -- Analyze parts specific to extended_return_statement:
694 Obj_Decl : constant Node_Id :=
695 Last (Return_Object_Declarations (N));
697 HSS : constant Node_Id := Handled_Statement_Sequence (N);
700 Expr := Expression (Obj_Decl);
702 -- Note: The check for OK_For_Limited_Init will happen in
703 -- Analyze_Object_Declaration; we treat it as a normal
704 -- object declaration.
706 Set_Is_Return_Object (Defining_Identifier (Obj_Decl));
709 Check_Return_Subtype_Indication (Obj_Decl);
711 if Present (HSS) then
714 if Present (Exception_Handlers (HSS)) then
716 -- ???Has_Nested_Block_With_Handler needs to be set.
717 -- Probably by creating an actual N_Block_Statement.
718 -- Probably in Expand.
724 -- Mark the return object as referenced, since the return is an
725 -- implicit reference of the object.
727 Set_Referenced (Defining_Identifier (Obj_Decl));
729 Check_References (Stm_Entity);
733 -- Case of Expr present
737 -- Defend against previous errors
739 and then Nkind (Expr) /= N_Empty
740 and then Present (Etype (Expr))
742 -- Apply constraint check. Note that this is done before the implicit
743 -- conversion of the expression done for anonymous access types to
744 -- ensure correct generation of the null-excluding check associated
745 -- with null-excluding expressions found in return statements.
747 Apply_Constraint_Check (Expr, R_Type);
749 -- Ada 2005 (AI-318-02): When the result type is an anonymous access
750 -- type, apply an implicit conversion of the expression to that type
751 -- to force appropriate static and run-time accessibility checks.
753 if Ada_Version >= Ada_2005
754 and then Ekind (R_Type) = E_Anonymous_Access_Type
756 Rewrite (Expr, Convert_To (R_Type, Relocate_Node (Expr)));
757 Analyze_And_Resolve (Expr, R_Type);
760 -- If the result type is class-wide, then check that the return
761 -- expression's type is not declared at a deeper level than the
762 -- function (RM05-6.5(5.6/2)).
764 if Ada_Version >= Ada_2005
765 and then Is_Class_Wide_Type (R_Type)
767 if Type_Access_Level (Etype (Expr)) >
768 Subprogram_Access_Level (Scope_Id)
771 ("level of return expression type is deeper than " &
772 "class-wide function!", Expr);
776 -- Check incorrect use of dynamically tagged expression
778 if Is_Tagged_Type (R_Type) then
779 Check_Dynamically_Tagged_Expression
785 -- ??? A real run-time accessibility check is needed in cases
786 -- involving dereferences of access parameters. For now we just
787 -- check the static cases.
789 if (Ada_Version < Ada_2005 or else Debug_Flag_Dot_L)
790 and then Is_Immutably_Limited_Type (Etype (Scope_Id))
791 and then Object_Access_Level (Expr) >
792 Subprogram_Access_Level (Scope_Id)
795 -- Suppress the message in a generic, where the rewriting
798 if Inside_A_Generic then
803 Make_Raise_Program_Error (Loc,
804 Reason => PE_Accessibility_Check_Failed));
808 ("cannot return a local value by reference?", N);
810 ("\& will be raised at run time?",
811 N, Standard_Program_Error);
816 and then Nkind (Parent (Scope_Id)) = N_Function_Specification
817 and then Null_Exclusion_Present (Parent (Scope_Id))
819 Apply_Compile_Time_Constraint_Error
821 Msg => "(Ada 2005) null not allowed for "
822 & "null-excluding return?",
823 Reason => CE_Null_Not_Allowed);
826 -- Apply checks suggested by AI05-0144 (dangerous order dependence)
828 Check_Order_Dependence;
830 end Analyze_Function_Return;
832 -------------------------------------
833 -- Analyze_Generic_Subprogram_Body --
834 -------------------------------------
836 procedure Analyze_Generic_Subprogram_Body
840 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
841 Kind : constant Entity_Kind := Ekind (Gen_Id);
847 -- Copy body and disable expansion while analyzing the generic For a
848 -- stub, do not copy the stub (which would load the proper body), this
849 -- will be done when the proper body is analyzed.
851 if Nkind (N) /= N_Subprogram_Body_Stub then
852 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
857 Spec := Specification (N);
859 -- Within the body of the generic, the subprogram is callable, and
860 -- behaves like the corresponding non-generic unit.
862 Body_Id := Defining_Entity (Spec);
864 if Kind = E_Generic_Procedure
865 and then Nkind (Spec) /= N_Procedure_Specification
867 Error_Msg_N ("invalid body for generic procedure ", Body_Id);
870 elsif Kind = E_Generic_Function
871 and then Nkind (Spec) /= N_Function_Specification
873 Error_Msg_N ("invalid body for generic function ", Body_Id);
877 Set_Corresponding_Body (Gen_Decl, Body_Id);
879 if Has_Completion (Gen_Id)
880 and then Nkind (Parent (N)) /= N_Subunit
882 Error_Msg_N ("duplicate generic body", N);
885 Set_Has_Completion (Gen_Id);
888 if Nkind (N) = N_Subprogram_Body_Stub then
889 Set_Ekind (Defining_Entity (Specification (N)), Kind);
891 Set_Corresponding_Spec (N, Gen_Id);
894 if Nkind (Parent (N)) = N_Compilation_Unit then
895 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
898 -- Make generic parameters immediately visible in the body. They are
899 -- needed to process the formals declarations. Then make the formals
900 -- visible in a separate step.
906 First_Ent : Entity_Id;
909 First_Ent := First_Entity (Gen_Id);
912 while Present (E) and then not Is_Formal (E) loop
917 Set_Use (Generic_Formal_Declarations (Gen_Decl));
919 -- Now generic formals are visible, and the specification can be
920 -- analyzed, for subsequent conformance check.
922 Body_Id := Analyze_Subprogram_Specification (Spec);
924 -- Make formal parameters visible
928 -- E is the first formal parameter, we loop through the formals
929 -- installing them so that they will be visible.
931 Set_First_Entity (Gen_Id, E);
932 while Present (E) loop
938 -- Visible generic entity is callable within its own body
940 Set_Ekind (Gen_Id, Ekind (Body_Id));
941 Set_Ekind (Body_Id, E_Subprogram_Body);
942 Set_Convention (Body_Id, Convention (Gen_Id));
943 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Gen_Id));
944 Set_Scope (Body_Id, Scope (Gen_Id));
945 Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id);
947 if Nkind (N) = N_Subprogram_Body_Stub then
949 -- No body to analyze, so restore state of generic unit
951 Set_Ekind (Gen_Id, Kind);
952 Set_Ekind (Body_Id, Kind);
954 if Present (First_Ent) then
955 Set_First_Entity (Gen_Id, First_Ent);
962 -- If this is a compilation unit, it must be made visible explicitly,
963 -- because the compilation of the declaration, unlike other library
964 -- unit declarations, does not. If it is not a unit, the following
965 -- is redundant but harmless.
967 Set_Is_Immediately_Visible (Gen_Id);
968 Reference_Body_Formals (Gen_Id, Body_Id);
970 if Is_Child_Unit (Gen_Id) then
971 Generate_Reference (Gen_Id, Scope (Gen_Id), 'k', False);
974 Set_Actual_Subtypes (N, Current_Scope);
976 -- Deal with preconditions and postconditions. In formal verification
977 -- mode, we keep pre- and postconditions attached to entities rather
978 -- than inserted in the code, in order to facilitate a distinct
979 -- treatment for them.
981 if not Alfa_Mode then
982 Process_PPCs (N, Gen_Id, Body_Id);
985 -- If the generic unit carries pre- or post-conditions, copy them
986 -- to the original generic tree, so that they are properly added
987 -- to any instantiation.
990 Orig : constant Node_Id := Original_Node (N);
994 Cond := First (Declarations (N));
995 while Present (Cond) loop
996 if Nkind (Cond) = N_Pragma
997 and then Pragma_Name (Cond) = Name_Check
999 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1001 elsif Nkind (Cond) = N_Pragma
1002 and then Pragma_Name (Cond) = Name_Postcondition
1004 Set_Ekind (Defining_Entity (Orig), Ekind (Gen_Id));
1005 Prepend (New_Copy_Tree (Cond), Declarations (Orig));
1014 Analyze_Declarations (Declarations (N));
1016 Analyze (Handled_Statement_Sequence (N));
1018 Save_Global_References (Original_Node (N));
1020 -- Prior to exiting the scope, include generic formals again (if any
1021 -- are present) in the set of local entities.
1023 if Present (First_Ent) then
1024 Set_First_Entity (Gen_Id, First_Ent);
1027 Check_References (Gen_Id);
1030 Process_End_Label (Handled_Statement_Sequence (N), 't', Current_Scope);
1032 Check_Subprogram_Order (N);
1034 -- Outside of its body, unit is generic again
1036 Set_Ekind (Gen_Id, Kind);
1037 Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False);
1040 Style.Check_Identifier (Body_Id, Gen_Id);
1044 end Analyze_Generic_Subprogram_Body;
1046 -----------------------------
1047 -- Analyze_Operator_Symbol --
1048 -----------------------------
1050 -- An operator symbol such as "+" or "and" may appear in context where the
1051 -- literal denotes an entity name, such as "+"(x, y) or in context when it
1052 -- is just a string, as in (conjunction = "or"). In these cases the parser
1053 -- generates this node, and the semantics does the disambiguation. Other
1054 -- such case are actuals in an instantiation, the generic unit in an
1055 -- instantiation, and pragma arguments.
1057 procedure Analyze_Operator_Symbol (N : Node_Id) is
1058 Par : constant Node_Id := Parent (N);
1061 if (Nkind (Par) = N_Function_Call
1062 and then N = Name (Par))
1063 or else Nkind (Par) = N_Function_Instantiation
1064 or else (Nkind (Par) = N_Indexed_Component
1065 and then N = Prefix (Par))
1066 or else (Nkind (Par) = N_Pragma_Argument_Association
1067 and then not Is_Pragma_String_Literal (Par))
1068 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
1069 or else (Nkind (Par) = N_Attribute_Reference
1070 and then Attribute_Name (Par) /= Name_Value)
1072 Find_Direct_Name (N);
1075 Change_Operator_Symbol_To_String_Literal (N);
1078 end Analyze_Operator_Symbol;
1080 -----------------------------------
1081 -- Analyze_Parameter_Association --
1082 -----------------------------------
1084 procedure Analyze_Parameter_Association (N : Node_Id) is
1086 Analyze (Explicit_Actual_Parameter (N));
1087 end Analyze_Parameter_Association;
1089 ----------------------------
1090 -- Analyze_Procedure_Call --
1091 ----------------------------
1093 procedure Analyze_Procedure_Call (N : Node_Id) is
1094 Loc : constant Source_Ptr := Sloc (N);
1095 P : constant Node_Id := Name (N);
1096 Actuals : constant List_Id := Parameter_Associations (N);
1100 procedure Analyze_Call_And_Resolve;
1101 -- Do Analyze and Resolve calls for procedure call
1102 -- At end, check illegal order dependence.
1104 ------------------------------
1105 -- Analyze_Call_And_Resolve --
1106 ------------------------------
1108 procedure Analyze_Call_And_Resolve is
1110 if Nkind (N) = N_Procedure_Call_Statement then
1112 Resolve (N, Standard_Void_Type);
1114 -- Apply checks suggested by AI05-0144
1116 Check_Order_Dependence;
1121 end Analyze_Call_And_Resolve;
1123 -- Start of processing for Analyze_Procedure_Call
1126 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
1127 -- a procedure call or an entry call. The prefix may denote an access
1128 -- to subprogram type, in which case an implicit dereference applies.
1129 -- If the prefix is an indexed component (without implicit dereference)
1130 -- then the construct denotes a call to a member of an entire family.
1131 -- If the prefix is a simple name, it may still denote a call to a
1132 -- parameterless member of an entry family. Resolution of these various
1133 -- interpretations is delicate.
1137 -- If this is a call of the form Obj.Op, the call may have been
1138 -- analyzed and possibly rewritten into a block, in which case
1141 if Analyzed (N) then
1145 -- If there is an error analyzing the name (which may have been
1146 -- rewritten if the original call was in prefix notation) then error
1147 -- has been emitted already, mark node and return.
1150 or else Etype (Name (N)) = Any_Type
1152 Set_Etype (N, Any_Type);
1156 -- Otherwise analyze the parameters
1158 if Present (Actuals) then
1159 Actual := First (Actuals);
1161 while Present (Actual) loop
1163 Check_Parameterless_Call (Actual);
1168 -- Special processing for Elab_Spec, Elab_Body and Elab_Subp_Body calls
1170 if Nkind (P) = N_Attribute_Reference
1171 and then (Attribute_Name (P) = Name_Elab_Spec
1172 or else Attribute_Name (P) = Name_Elab_Body
1173 or else Attribute_Name (P) = Name_Elab_Subp_Body)
1175 if Present (Actuals) then
1177 ("no parameters allowed for this call", First (Actuals));
1181 Set_Etype (N, Standard_Void_Type);
1184 elsif Is_Entity_Name (P)
1185 and then Is_Record_Type (Etype (Entity (P)))
1186 and then Remote_AST_I_Dereference (P)
1190 elsif Is_Entity_Name (P)
1191 and then Ekind (Entity (P)) /= E_Entry_Family
1193 if Is_Access_Type (Etype (P))
1194 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1195 and then No (Actuals)
1196 and then Comes_From_Source (N)
1198 Error_Msg_N ("missing explicit dereference in call", N);
1201 Analyze_Call_And_Resolve;
1203 -- If the prefix is the simple name of an entry family, this is
1204 -- a parameterless call from within the task body itself.
1206 elsif Is_Entity_Name (P)
1207 and then Nkind (P) = N_Identifier
1208 and then Ekind (Entity (P)) = E_Entry_Family
1209 and then Present (Actuals)
1210 and then No (Next (First (Actuals)))
1212 -- Can be call to parameterless entry family. What appears to be the
1213 -- sole argument is in fact the entry index. Rewrite prefix of node
1214 -- accordingly. Source representation is unchanged by this
1218 Make_Indexed_Component (Loc,
1220 Make_Selected_Component (Loc,
1221 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
1222 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
1223 Expressions => Actuals);
1224 Set_Name (N, New_N);
1225 Set_Etype (New_N, Standard_Void_Type);
1226 Set_Parameter_Associations (N, No_List);
1227 Analyze_Call_And_Resolve;
1229 elsif Nkind (P) = N_Explicit_Dereference then
1230 if Ekind (Etype (P)) = E_Subprogram_Type then
1231 Analyze_Call_And_Resolve;
1233 Error_Msg_N ("expect access to procedure in call", P);
1236 -- The name can be a selected component or an indexed component that
1237 -- yields an access to subprogram. Such a prefix is legal if the call
1238 -- has parameter associations.
1240 elsif Is_Access_Type (Etype (P))
1241 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
1243 if Present (Actuals) then
1244 Analyze_Call_And_Resolve;
1246 Error_Msg_N ("missing explicit dereference in call ", N);
1249 -- If not an access to subprogram, then the prefix must resolve to the
1250 -- name of an entry, entry family, or protected operation.
1252 -- For the case of a simple entry call, P is a selected component where
1253 -- the prefix is the task and the selector name is the entry. A call to
1254 -- a protected procedure will have the same syntax. If the protected
1255 -- object contains overloaded operations, the entity may appear as a
1256 -- function, the context will select the operation whose type is Void.
1258 elsif Nkind (P) = N_Selected_Component
1259 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
1261 Ekind (Entity (Selector_Name (P))) = E_Procedure
1263 Ekind (Entity (Selector_Name (P))) = E_Function)
1265 Analyze_Call_And_Resolve;
1267 elsif Nkind (P) = N_Selected_Component
1268 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
1269 and then Present (Actuals)
1270 and then No (Next (First (Actuals)))
1272 -- Can be call to parameterless entry family. What appears to be the
1273 -- sole argument is in fact the entry index. Rewrite prefix of node
1274 -- accordingly. Source representation is unchanged by this
1278 Make_Indexed_Component (Loc,
1279 Prefix => New_Copy (P),
1280 Expressions => Actuals);
1281 Set_Name (N, New_N);
1282 Set_Etype (New_N, Standard_Void_Type);
1283 Set_Parameter_Associations (N, No_List);
1284 Analyze_Call_And_Resolve;
1286 -- For the case of a reference to an element of an entry family, P is
1287 -- an indexed component whose prefix is a selected component (task and
1288 -- entry family), and whose index is the entry family index.
1290 elsif Nkind (P) = N_Indexed_Component
1291 and then Nkind (Prefix (P)) = N_Selected_Component
1292 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
1294 Analyze_Call_And_Resolve;
1296 -- If the prefix is the name of an entry family, it is a call from
1297 -- within the task body itself.
1299 elsif Nkind (P) = N_Indexed_Component
1300 and then Nkind (Prefix (P)) = N_Identifier
1301 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
1304 Make_Selected_Component (Loc,
1305 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
1306 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
1307 Rewrite (Prefix (P), New_N);
1309 Analyze_Call_And_Resolve;
1311 -- Anything else is an error
1314 Error_Msg_N ("invalid procedure or entry call", N);
1316 end Analyze_Procedure_Call;
1318 ------------------------------
1319 -- Analyze_Return_Statement --
1320 ------------------------------
1322 procedure Analyze_Return_Statement (N : Node_Id) is
1324 pragma Assert (Nkind_In (N, N_Simple_Return_Statement,
1325 N_Extended_Return_Statement));
1327 Returns_Object : constant Boolean :=
1328 Nkind (N) = N_Extended_Return_Statement
1330 (Nkind (N) = N_Simple_Return_Statement
1331 and then Present (Expression (N)));
1332 -- True if we're returning something; that is, "return <expression>;"
1333 -- or "return Result : T [:= ...]". False for "return;". Used for error
1334 -- checking: If Returns_Object is True, N should apply to a function
1335 -- body; otherwise N should apply to a procedure body, entry body,
1336 -- accept statement, or extended return statement.
1338 function Find_What_It_Applies_To return Entity_Id;
1339 -- Find the entity representing the innermost enclosing body, accept
1340 -- statement, or extended return statement. If the result is a callable
1341 -- construct or extended return statement, then this will be the value
1342 -- of the Return_Applies_To attribute. Otherwise, the program is
1343 -- illegal. See RM-6.5(4/2).
1345 -----------------------------
1346 -- Find_What_It_Applies_To --
1347 -----------------------------
1349 function Find_What_It_Applies_To return Entity_Id is
1350 Result : Entity_Id := Empty;
1353 -- Loop outward through the Scope_Stack, skipping blocks and loops
1355 for J in reverse 0 .. Scope_Stack.Last loop
1356 Result := Scope_Stack.Table (J).Entity;
1357 exit when Ekind (Result) /= E_Block and then
1358 Ekind (Result) /= E_Loop;
1361 pragma Assert (Present (Result));
1363 end Find_What_It_Applies_To;
1365 -- Local declarations
1367 Scope_Id : constant Entity_Id := Find_What_It_Applies_To;
1368 Kind : constant Entity_Kind := Ekind (Scope_Id);
1369 Loc : constant Source_Ptr := Sloc (N);
1370 Stm_Entity : constant Entity_Id :=
1372 (E_Return_Statement, Current_Scope, Loc, 'R');
1374 -- Start of processing for Analyze_Return_Statement
1377 Set_Return_Statement_Entity (N, Stm_Entity);
1379 Set_Etype (Stm_Entity, Standard_Void_Type);
1380 Set_Return_Applies_To (Stm_Entity, Scope_Id);
1382 -- Place Return entity on scope stack, to simplify enforcement of 6.5
1383 -- (4/2): an inner return statement will apply to this extended return.
1385 if Nkind (N) = N_Extended_Return_Statement then
1386 Push_Scope (Stm_Entity);
1389 -- Check that pragma No_Return is obeyed. Don't complain about the
1390 -- implicitly-generated return that is placed at the end.
1392 if No_Return (Scope_Id) and then Comes_From_Source (N) then
1393 Error_Msg_N ("RETURN statement not allowed (No_Return)", N);
1396 -- Warn on any unassigned OUT parameters if in procedure
1398 if Ekind (Scope_Id) = E_Procedure then
1399 Warn_On_Unassigned_Out_Parameter (N, Scope_Id);
1402 -- Check that functions return objects, and other things do not
1404 if Kind = E_Function or else Kind = E_Generic_Function then
1405 if not Returns_Object then
1406 Error_Msg_N ("missing expression in return from function", N);
1409 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
1410 if Returns_Object then
1411 Error_Msg_N ("procedure cannot return value (use function)", N);
1414 elsif Kind = E_Entry or else Kind = E_Entry_Family then
1415 if Returns_Object then
1416 if Is_Protected_Type (Scope (Scope_Id)) then
1417 Error_Msg_N ("entry body cannot return value", N);
1419 Error_Msg_N ("accept statement cannot return value", N);
1423 elsif Kind = E_Return_Statement then
1425 -- We are nested within another return statement, which must be an
1426 -- extended_return_statement.
1428 if Returns_Object then
1430 ("extended_return_statement cannot return value; " &
1431 "use `""RETURN;""`", N);
1435 Error_Msg_N ("illegal context for return statement", N);
1438 if Ekind_In (Kind, E_Function, E_Generic_Function) then
1439 Analyze_Function_Return (N);
1441 elsif Ekind_In (Kind, E_Procedure, E_Generic_Procedure) then
1442 Set_Return_Present (Scope_Id);
1445 if Nkind (N) = N_Extended_Return_Statement then
1449 Kill_Current_Values (Last_Assignment_Only => True);
1450 Check_Unreachable_Code (N);
1451 end Analyze_Return_Statement;
1453 -------------------------------------
1454 -- Analyze_Simple_Return_Statement --
1455 -------------------------------------
1457 procedure Analyze_Simple_Return_Statement (N : Node_Id) is
1459 if Present (Expression (N)) then
1460 Mark_Coextensions (N, Expression (N));
1463 Analyze_Return_Statement (N);
1464 end Analyze_Simple_Return_Statement;
1466 -------------------------
1467 -- Analyze_Return_Type --
1468 -------------------------
1470 procedure Analyze_Return_Type (N : Node_Id) is
1471 Designator : constant Entity_Id := Defining_Entity (N);
1472 Typ : Entity_Id := Empty;
1475 -- Normal case where result definition does not indicate an error
1477 if Result_Definition (N) /= Error then
1478 if Nkind (Result_Definition (N)) = N_Access_Definition then
1479 Check_SPARK_Restriction
1480 ("access result is not allowed", Result_Definition (N));
1482 -- Ada 2005 (AI-254): Handle anonymous access to subprograms
1485 AD : constant Node_Id :=
1486 Access_To_Subprogram_Definition (Result_Definition (N));
1488 if Present (AD) and then Protected_Present (AD) then
1489 Typ := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1491 Typ := Access_Definition (N, Result_Definition (N));
1495 Set_Parent (Typ, Result_Definition (N));
1496 Set_Is_Local_Anonymous_Access (Typ);
1497 Set_Etype (Designator, Typ);
1499 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1501 Null_Exclusion_Static_Checks (N);
1503 -- Subtype_Mark case
1506 Find_Type (Result_Definition (N));
1507 Typ := Entity (Result_Definition (N));
1508 Set_Etype (Designator, Typ);
1510 -- Unconstrained array as result is not allowed in SPARK
1512 if Is_Array_Type (Typ)
1513 and then not Is_Constrained (Typ)
1515 Check_SPARK_Restriction
1516 ("returning an unconstrained array is not allowed",
1517 Result_Definition (N));
1520 -- Ada 2005 (AI-231): Ensure proper usage of null exclusion
1522 Null_Exclusion_Static_Checks (N);
1524 -- If a null exclusion is imposed on the result type, then create
1525 -- a null-excluding itype (an access subtype) and use it as the
1526 -- function's Etype. Note that the null exclusion checks are done
1527 -- right before this, because they don't get applied to types that
1528 -- do not come from source.
1530 if Is_Access_Type (Typ)
1531 and then Null_Exclusion_Present (N)
1533 Set_Etype (Designator,
1534 Create_Null_Excluding_Itype
1537 Scope_Id => Scope (Current_Scope)));
1539 -- The new subtype must be elaborated before use because
1540 -- it is visible outside of the function. However its base
1541 -- type may not be frozen yet, so the reference that will
1542 -- force elaboration must be attached to the freezing of
1545 -- If the return specification appears on a proper body,
1546 -- the subtype will have been created already on the spec.
1548 if Is_Frozen (Typ) then
1549 if Nkind (Parent (N)) = N_Subprogram_Body
1550 and then Nkind (Parent (Parent (N))) = N_Subunit
1554 Build_Itype_Reference (Etype (Designator), Parent (N));
1558 Ensure_Freeze_Node (Typ);
1561 IR : constant Node_Id := Make_Itype_Reference (Sloc (N));
1563 Set_Itype (IR, Etype (Designator));
1564 Append_Freeze_Actions (Typ, New_List (IR));
1569 Set_Etype (Designator, Typ);
1572 if Ekind (Typ) = E_Incomplete_Type
1573 and then Is_Value_Type (Typ)
1577 elsif Ekind (Typ) = E_Incomplete_Type
1578 or else (Is_Class_Wide_Type (Typ)
1580 Ekind (Root_Type (Typ)) = E_Incomplete_Type)
1582 -- AI05-0151: Tagged incomplete types are allowed in all formal
1583 -- parts. Untagged incomplete types are not allowed in bodies.
1585 if Ada_Version >= Ada_2012 then
1586 if Is_Tagged_Type (Typ) then
1589 elsif Nkind_In (Parent (Parent (N)),
1595 ("invalid use of untagged incomplete type&",
1599 -- The type must be completed in the current package. This
1600 -- is checked at the end of the package declaraton, when
1601 -- Taft amemdment types are identified.
1603 if Ekind (Scope (Current_Scope)) = E_Package
1604 and then In_Private_Part (Scope (Current_Scope))
1606 Append_Elmt (Designator, Private_Dependents (Typ));
1611 ("invalid use of incomplete type&", Designator, Typ);
1616 -- Case where result definition does indicate an error
1619 Set_Etype (Designator, Any_Type);
1621 end Analyze_Return_Type;
1623 -----------------------------
1624 -- Analyze_Subprogram_Body --
1625 -----------------------------
1627 procedure Analyze_Subprogram_Body (N : Node_Id) is
1628 Loc : constant Source_Ptr := Sloc (N);
1629 Body_Spec : constant Node_Id := Specification (N);
1630 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
1633 if Debug_Flag_C then
1634 Write_Str ("==> subprogram body ");
1635 Write_Name (Chars (Body_Id));
1636 Write_Str (" from ");
1637 Write_Location (Loc);
1642 Trace_Scope (N, Body_Id, " Analyze subprogram: ");
1644 -- The real work is split out into the helper, so it can do "return;"
1645 -- without skipping the debug output:
1647 Analyze_Subprogram_Body_Helper (N);
1649 if Debug_Flag_C then
1651 Write_Str ("<== subprogram body ");
1652 Write_Name (Chars (Body_Id));
1653 Write_Str (" from ");
1654 Write_Location (Loc);
1657 end Analyze_Subprogram_Body;
1659 ------------------------------------
1660 -- Analyze_Subprogram_Body_Helper --
1661 ------------------------------------
1663 -- This procedure is called for regular subprogram bodies, generic bodies,
1664 -- and for subprogram stubs of both kinds. In the case of stubs, only the
1665 -- specification matters, and is used to create a proper declaration for
1666 -- the subprogram, or to perform conformance checks.
1668 procedure Analyze_Subprogram_Body_Helper (N : Node_Id) is
1669 Loc : constant Source_Ptr := Sloc (N);
1670 Body_Deleted : constant Boolean := False;
1671 Body_Spec : constant Node_Id := Specification (N);
1672 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
1673 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
1674 Conformant : Boolean;
1677 Prot_Typ : Entity_Id := Empty;
1678 Spec_Id : Entity_Id;
1679 Spec_Decl : Node_Id := Empty;
1681 Last_Real_Spec_Entity : Entity_Id := Empty;
1682 -- When we analyze a separate spec, the entity chain ends up containing
1683 -- the formals, as well as any itypes generated during analysis of the
1684 -- default expressions for parameters, or the arguments of associated
1685 -- precondition/postcondition pragmas (which are analyzed in the context
1686 -- of the spec since they have visibility on formals).
1688 -- These entities belong with the spec and not the body. However we do
1689 -- the analysis of the body in the context of the spec (again to obtain
1690 -- visibility to the formals), and all the entities generated during
1691 -- this analysis end up also chained to the entity chain of the spec.
1692 -- But they really belong to the body, and there is circuitry to move
1693 -- them from the spec to the body.
1695 -- However, when we do this move, we don't want to move the real spec
1696 -- entities (first para above) to the body. The Last_Real_Spec_Entity
1697 -- variable points to the last real spec entity, so we only move those
1698 -- chained beyond that point. It is initialized to Empty to deal with
1699 -- the case where there is no separate spec.
1701 procedure Check_Anonymous_Return;
1702 -- Ada 2005: if a function returns an access type that denotes a task,
1703 -- or a type that contains tasks, we must create a master entity for
1704 -- the anonymous type, which typically will be used in an allocator
1705 -- in the body of the function.
1707 procedure Check_Inline_Pragma (Spec : in out Node_Id);
1708 -- Look ahead to recognize a pragma that may appear after the body.
1709 -- If there is a previous spec, check that it appears in the same
1710 -- declarative part. If the pragma is Inline_Always, perform inlining
1711 -- unconditionally, otherwise only if Front_End_Inlining is requested.
1712 -- If the body acts as a spec, and inlining is required, we create a
1713 -- subprogram declaration for it, in order to attach the body to inline.
1714 -- If pragma does not appear after the body, check whether there is
1715 -- an inline pragma before any local declarations.
1717 procedure Check_Missing_Return;
1718 -- Checks for a function with a no return statements, and also performs
1719 -- the warning checks implemented by Check_Returns. In formal mode, also
1720 -- verify that a function ends with a RETURN and that a procedure does
1721 -- not contain any RETURN.
1723 function Disambiguate_Spec return Entity_Id;
1724 -- When a primitive is declared between the private view and the full
1725 -- view of a concurrent type which implements an interface, a special
1726 -- mechanism is used to find the corresponding spec of the primitive
1729 function Is_Private_Concurrent_Primitive
1730 (Subp_Id : Entity_Id) return Boolean;
1731 -- Determine whether subprogram Subp_Id is a primitive of a concurrent
1732 -- type that implements an interface and has a private view.
1734 procedure Set_Trivial_Subprogram (N : Node_Id);
1735 -- Sets the Is_Trivial_Subprogram flag in both spec and body of the
1736 -- subprogram whose body is being analyzed. N is the statement node
1737 -- causing the flag to be set, if the following statement is a return
1738 -- of an entity, we mark the entity as set in source to suppress any
1739 -- warning on the stylized use of function stubs with a dummy return.
1741 procedure Verify_Overriding_Indicator;
1742 -- If there was a previous spec, the entity has been entered in the
1743 -- current scope previously. If the body itself carries an overriding
1744 -- indicator, check that it is consistent with the known status of the
1747 ----------------------------
1748 -- Check_Anonymous_Return --
1749 ----------------------------
1751 procedure Check_Anonymous_Return is
1757 if Present (Spec_Id) then
1763 if Ekind (Scop) = E_Function
1764 and then Ekind (Etype (Scop)) = E_Anonymous_Access_Type
1765 and then not Is_Thunk (Scop)
1766 and then (Has_Task (Designated_Type (Etype (Scop)))
1768 (Is_Class_Wide_Type (Designated_Type (Etype (Scop)))
1770 Is_Limited_Record (Designated_Type (Etype (Scop)))))
1771 and then Expander_Active
1773 -- Avoid cases with no tasking support
1775 and then RTE_Available (RE_Current_Master)
1776 and then not Restriction_Active (No_Task_Hierarchy)
1779 Make_Object_Declaration (Loc,
1780 Defining_Identifier =>
1781 Make_Defining_Identifier (Loc, Name_uMaster),
1782 Constant_Present => True,
1783 Object_Definition =>
1784 New_Reference_To (RTE (RE_Master_Id), Loc),
1786 Make_Explicit_Dereference (Loc,
1787 New_Reference_To (RTE (RE_Current_Master), Loc)));
1789 if Present (Declarations (N)) then
1790 Prepend (Decl, Declarations (N));
1792 Set_Declarations (N, New_List (Decl));
1795 Set_Master_Id (Etype (Scop), Defining_Identifier (Decl));
1796 Set_Has_Master_Entity (Scop);
1798 -- Now mark the containing scope as a task master
1801 while Nkind (Par) /= N_Compilation_Unit loop
1802 Par := Parent (Par);
1803 pragma Assert (Present (Par));
1805 -- If we fall off the top, we are at the outer level, and
1806 -- the environment task is our effective master, so nothing
1810 (Par, N_Task_Body, N_Block_Statement, N_Subprogram_Body)
1812 Set_Is_Task_Master (Par, True);
1817 end Check_Anonymous_Return;
1819 -------------------------
1820 -- Check_Inline_Pragma --
1821 -------------------------
1823 procedure Check_Inline_Pragma (Spec : in out Node_Id) is
1827 function Is_Inline_Pragma (N : Node_Id) return Boolean;
1828 -- True when N is a pragma Inline or Inline_Always that applies
1829 -- to this subprogram.
1831 -----------------------
1832 -- Is_Inline_Pragma --
1833 -----------------------
1835 function Is_Inline_Pragma (N : Node_Id) return Boolean is
1838 Nkind (N) = N_Pragma
1840 (Pragma_Name (N) = Name_Inline_Always
1843 and then Pragma_Name (N) = Name_Inline))
1846 (Expression (First (Pragma_Argument_Associations (N))))
1848 end Is_Inline_Pragma;
1850 -- Start of processing for Check_Inline_Pragma
1853 if not Expander_Active then
1857 if Is_List_Member (N)
1858 and then Present (Next (N))
1859 and then Is_Inline_Pragma (Next (N))
1863 elsif Nkind (N) /= N_Subprogram_Body_Stub
1864 and then Present (Declarations (N))
1865 and then Is_Inline_Pragma (First (Declarations (N)))
1867 Prag := First (Declarations (N));
1873 if Present (Prag) then
1874 if Present (Spec_Id) then
1875 if In_Same_List (N, Unit_Declaration_Node (Spec_Id)) then
1880 -- Create a subprogram declaration, to make treatment uniform
1883 Subp : constant Entity_Id :=
1884 Make_Defining_Identifier (Loc, Chars (Body_Id));
1885 Decl : constant Node_Id :=
1886 Make_Subprogram_Declaration (Loc,
1888 New_Copy_Tree (Specification (N)));
1891 Set_Defining_Unit_Name (Specification (Decl), Subp);
1893 if Present (First_Formal (Body_Id)) then
1894 Plist := Copy_Parameter_List (Body_Id);
1895 Set_Parameter_Specifications
1896 (Specification (Decl), Plist);
1899 Insert_Before (N, Decl);
1902 Set_Has_Pragma_Inline (Subp);
1904 if Pragma_Name (Prag) = Name_Inline_Always then
1905 Set_Is_Inlined (Subp);
1906 Set_Has_Pragma_Inline_Always (Subp);
1913 end Check_Inline_Pragma;
1915 --------------------------
1916 -- Check_Missing_Return --
1917 --------------------------
1919 procedure Check_Missing_Return is
1921 Missing_Ret : Boolean;
1924 if Nkind (Body_Spec) = N_Function_Specification then
1925 if Present (Spec_Id) then
1931 if Return_Present (Id) then
1932 Check_Returns (HSS, 'F', Missing_Ret);
1935 Set_Has_Missing_Return (Id);
1938 elsif (Is_Generic_Subprogram (Id)
1939 or else not Is_Machine_Code_Subprogram (Id))
1940 and then not Body_Deleted
1942 Error_Msg_N ("missing RETURN statement in function body", N);
1945 -- If procedure with No_Return, check returns
1947 elsif Nkind (Body_Spec) = N_Procedure_Specification
1948 and then Present (Spec_Id)
1949 and then No_Return (Spec_Id)
1951 Check_Returns (HSS, 'P', Missing_Ret, Spec_Id);
1954 -- Special checks in SPARK mode
1956 if Nkind (Body_Spec) = N_Function_Specification then
1958 -- In SPARK mode, last statement of a function should be a return
1961 Stat : constant Node_Id := Last_Source_Statement (HSS);
1964 and then not Nkind_In (Stat, N_Simple_Return_Statement,
1965 N_Extended_Return_Statement)
1967 Check_SPARK_Restriction
1968 ("last statement in function should be RETURN", Stat);
1972 -- In SPARK mode, verify that a procedure has no return
1974 elsif Nkind (Body_Spec) = N_Procedure_Specification then
1975 if Present (Spec_Id) then
1981 -- Would be nice to point to return statement here, can we
1982 -- borrow the Check_Returns procedure here ???
1984 if Return_Present (Id) then
1985 Check_SPARK_Restriction
1986 ("procedure should not have RETURN", N);
1989 end Check_Missing_Return;
1991 -----------------------
1992 -- Disambiguate_Spec --
1993 -----------------------
1995 function Disambiguate_Spec return Entity_Id is
1996 Priv_Spec : Entity_Id;
1999 procedure Replace_Types (To_Corresponding : Boolean);
2000 -- Depending on the flag, replace the type of formal parameters of
2001 -- Body_Id if it is a concurrent type implementing interfaces with
2002 -- the corresponding record type or the other way around.
2004 procedure Replace_Types (To_Corresponding : Boolean) is
2006 Formal_Typ : Entity_Id;
2009 Formal := First_Formal (Body_Id);
2010 while Present (Formal) loop
2011 Formal_Typ := Etype (Formal);
2013 if Is_Class_Wide_Type (Formal_Typ) then
2014 Formal_Typ := Root_Type (Formal_Typ);
2017 -- From concurrent type to corresponding record
2019 if To_Corresponding then
2020 if Is_Concurrent_Type (Formal_Typ)
2021 and then Present (Corresponding_Record_Type (Formal_Typ))
2022 and then Present (Interfaces (
2023 Corresponding_Record_Type (Formal_Typ)))
2026 Corresponding_Record_Type (Formal_Typ));
2029 -- From corresponding record to concurrent type
2032 if Is_Concurrent_Record_Type (Formal_Typ)
2033 and then Present (Interfaces (Formal_Typ))
2036 Corresponding_Concurrent_Type (Formal_Typ));
2040 Next_Formal (Formal);
2044 -- Start of processing for Disambiguate_Spec
2047 -- Try to retrieve the specification of the body as is. All error
2048 -- messages are suppressed because the body may not have a spec in
2049 -- its current state.
2051 Spec_N := Find_Corresponding_Spec (N, False);
2053 -- It is possible that this is the body of a primitive declared
2054 -- between a private and a full view of a concurrent type. The
2055 -- controlling parameter of the spec carries the concurrent type,
2056 -- not the corresponding record type as transformed by Analyze_
2057 -- Subprogram_Specification. In such cases, we undo the change
2058 -- made by the analysis of the specification and try to find the
2061 -- Note that wrappers already have their corresponding specs and
2062 -- bodies set during their creation, so if the candidate spec is
2063 -- a wrapper, then we definitely need to swap all types to their
2064 -- original concurrent status.
2067 or else Is_Primitive_Wrapper (Spec_N)
2069 -- Restore all references of corresponding record types to the
2070 -- original concurrent types.
2072 Replace_Types (To_Corresponding => False);
2073 Priv_Spec := Find_Corresponding_Spec (N, False);
2075 -- The current body truly belongs to a primitive declared between
2076 -- a private and a full view. We leave the modified body as is,
2077 -- and return the true spec.
2079 if Present (Priv_Spec)
2080 and then Is_Private_Primitive (Priv_Spec)
2085 -- In case that this is some sort of error, restore the original
2086 -- state of the body.
2088 Replace_Types (To_Corresponding => True);
2092 end Disambiguate_Spec;
2094 -------------------------------------
2095 -- Is_Private_Concurrent_Primitive --
2096 -------------------------------------
2098 function Is_Private_Concurrent_Primitive
2099 (Subp_Id : Entity_Id) return Boolean
2101 Formal_Typ : Entity_Id;
2104 if Present (First_Formal (Subp_Id)) then
2105 Formal_Typ := Etype (First_Formal (Subp_Id));
2107 if Is_Concurrent_Record_Type (Formal_Typ) then
2108 if Is_Class_Wide_Type (Formal_Typ) then
2109 Formal_Typ := Root_Type (Formal_Typ);
2112 Formal_Typ := Corresponding_Concurrent_Type (Formal_Typ);
2115 -- The type of the first formal is a concurrent tagged type with
2119 Is_Concurrent_Type (Formal_Typ)
2120 and then Is_Tagged_Type (Formal_Typ)
2121 and then Has_Private_Declaration (Formal_Typ);
2125 end Is_Private_Concurrent_Primitive;
2127 ----------------------------
2128 -- Set_Trivial_Subprogram --
2129 ----------------------------
2131 procedure Set_Trivial_Subprogram (N : Node_Id) is
2132 Nxt : constant Node_Id := Next (N);
2135 Set_Is_Trivial_Subprogram (Body_Id);
2137 if Present (Spec_Id) then
2138 Set_Is_Trivial_Subprogram (Spec_Id);
2142 and then Nkind (Nxt) = N_Simple_Return_Statement
2143 and then No (Next (Nxt))
2144 and then Present (Expression (Nxt))
2145 and then Is_Entity_Name (Expression (Nxt))
2147 Set_Never_Set_In_Source (Entity (Expression (Nxt)), False);
2149 end Set_Trivial_Subprogram;
2151 ---------------------------------
2152 -- Verify_Overriding_Indicator --
2153 ---------------------------------
2155 procedure Verify_Overriding_Indicator is
2157 if Must_Override (Body_Spec) then
2158 if Nkind (Spec_Id) = N_Defining_Operator_Symbol
2159 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2163 elsif not Present (Overridden_Operation (Spec_Id)) then
2165 ("subprogram& is not overriding", Body_Spec, Spec_Id);
2168 elsif Must_Not_Override (Body_Spec) then
2169 if Present (Overridden_Operation (Spec_Id)) then
2171 ("subprogram& overrides inherited operation",
2172 Body_Spec, Spec_Id);
2174 elsif Nkind (Spec_Id) = N_Defining_Operator_Symbol
2175 and then Operator_Matches_Spec (Spec_Id, Spec_Id)
2178 ("subprogram & overrides predefined operator ",
2179 Body_Spec, Spec_Id);
2181 -- If this is not a primitive operation or protected subprogram,
2182 -- then the overriding indicator is altogether illegal.
2184 elsif not Is_Primitive (Spec_Id)
2185 and then Ekind (Scope (Spec_Id)) /= E_Protected_Type
2188 ("overriding indicator only allowed " &
2189 "if subprogram is primitive",
2194 and then Present (Overridden_Operation (Spec_Id))
2196 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2197 Style.Missing_Overriding (N, Body_Id);
2200 and then Can_Override_Operator (Spec_Id)
2201 and then not Is_Predefined_File_Name
2202 (Unit_File_Name (Get_Source_Unit (Spec_Id)))
2204 pragma Assert (Unit_Declaration_Node (Body_Id) = N);
2205 Style.Missing_Overriding (N, Body_Id);
2207 end Verify_Overriding_Indicator;
2209 -- Start of processing for Analyze_Subprogram_Body_Helper
2212 -- Generic subprograms are handled separately. They always have a
2213 -- generic specification. Determine whether current scope has a
2214 -- previous declaration.
2216 -- If the subprogram body is defined within an instance of the same
2217 -- name, the instance appears as a package renaming, and will be hidden
2218 -- within the subprogram.
2220 if Present (Prev_Id)
2221 and then not Is_Overloadable (Prev_Id)
2222 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
2223 or else Comes_From_Source (Prev_Id))
2225 if Is_Generic_Subprogram (Prev_Id) then
2227 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2228 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2230 Analyze_Generic_Subprogram_Body (N, Spec_Id);
2232 if Nkind (N) = N_Subprogram_Body then
2233 HSS := Handled_Statement_Sequence (N);
2234 Check_Missing_Return;
2240 -- Previous entity conflicts with subprogram name. Attempting to
2241 -- enter name will post error.
2243 Enter_Name (Body_Id);
2247 -- Non-generic case, find the subprogram declaration, if one was seen,
2248 -- or enter new overloaded entity in the current scope. If the
2249 -- Current_Entity is the Body_Id itself, the unit is being analyzed as
2250 -- part of the context of one of its subunits. No need to redo the
2253 elsif Prev_Id = Body_Id
2254 and then Has_Completion (Body_Id)
2259 Body_Id := Analyze_Subprogram_Specification (Body_Spec);
2261 if Nkind (N) = N_Subprogram_Body_Stub
2262 or else No (Corresponding_Spec (N))
2264 if Is_Private_Concurrent_Primitive (Body_Id) then
2265 Spec_Id := Disambiguate_Spec;
2267 Spec_Id := Find_Corresponding_Spec (N);
2270 -- If this is a duplicate body, no point in analyzing it
2272 if Error_Posted (N) then
2276 -- A subprogram body should cause freezing of its own declaration,
2277 -- but if there was no previous explicit declaration, then the
2278 -- subprogram will get frozen too late (there may be code within
2279 -- the body that depends on the subprogram having been frozen,
2280 -- such as uses of extra formals), so we force it to be frozen
2281 -- here. Same holds if the body and spec are compilation units.
2282 -- Finally, if the return type is an anonymous access to protected
2283 -- subprogram, it must be frozen before the body because its
2284 -- expansion has generated an equivalent type that is used when
2285 -- elaborating the body.
2287 if No (Spec_Id) then
2288 Freeze_Before (N, Body_Id);
2290 elsif Nkind (Parent (N)) = N_Compilation_Unit then
2291 Freeze_Before (N, Spec_Id);
2293 elsif Is_Access_Subprogram_Type (Etype (Body_Id)) then
2294 Freeze_Before (N, Etype (Body_Id));
2298 Spec_Id := Corresponding_Spec (N);
2302 -- Do not inline any subprogram that contains nested subprograms, since
2303 -- the backend inlining circuit seems to generate uninitialized
2304 -- references in this case. We know this happens in the case of front
2305 -- end ZCX support, but it also appears it can happen in other cases as
2306 -- well. The backend often rejects attempts to inline in the case of
2307 -- nested procedures anyway, so little if anything is lost by this.
2308 -- Note that this is test is for the benefit of the back-end. There is
2309 -- a separate test for front-end inlining that also rejects nested
2312 -- Do not do this test if errors have been detected, because in some
2313 -- error cases, this code blows up, and we don't need it anyway if
2314 -- there have been errors, since we won't get to the linker anyway.
2316 if Comes_From_Source (Body_Id)
2317 and then Serious_Errors_Detected = 0
2321 P_Ent := Scope (P_Ent);
2322 exit when No (P_Ent) or else P_Ent = Standard_Standard;
2324 if Is_Subprogram (P_Ent) then
2325 Set_Is_Inlined (P_Ent, False);
2327 if Comes_From_Source (P_Ent)
2328 and then Has_Pragma_Inline (P_Ent)
2331 ("cannot inline& (nested subprogram)?",
2338 Check_Inline_Pragma (Spec_Id);
2340 -- Deal with special case of a fully private operation in the body of
2341 -- the protected type. We must create a declaration for the subprogram,
2342 -- in order to attach the protected subprogram that will be used in
2343 -- internal calls. We exclude compiler generated bodies from the
2344 -- expander since the issue does not arise for those cases.
2347 and then Comes_From_Source (N)
2348 and then Is_Protected_Type (Current_Scope)
2350 Spec_Id := Build_Private_Protected_Declaration (N);
2353 -- If a separate spec is present, then deal with freezing issues
2355 if Present (Spec_Id) then
2356 Spec_Decl := Unit_Declaration_Node (Spec_Id);
2357 Verify_Overriding_Indicator;
2359 -- In general, the spec will be frozen when we start analyzing the
2360 -- body. However, for internally generated operations, such as
2361 -- wrapper functions for inherited operations with controlling
2362 -- results, the spec may not have been frozen by the time we expand
2363 -- the freeze actions that include the bodies. In particular, extra
2364 -- formals for accessibility or for return-in-place may need to be
2365 -- generated. Freeze nodes, if any, are inserted before the current
2366 -- body. These freeze actions are also needed in ASIS mode to enable
2367 -- the proper back-annotations.
2369 if not Is_Frozen (Spec_Id)
2370 and then (Expander_Active or ASIS_Mode)
2372 -- Force the generation of its freezing node to ensure proper
2373 -- management of access types in the backend.
2375 -- This is definitely needed for some cases, but it is not clear
2376 -- why, to be investigated further???
2378 Set_Has_Delayed_Freeze (Spec_Id);
2379 Freeze_Before (N, Spec_Id);
2383 -- Mark presence of postcondition procedure in current scope and mark
2384 -- the procedure itself as needing debug info. The latter is important
2385 -- when analyzing decision coverage (for example, for MC/DC coverage).
2387 if Chars (Body_Id) = Name_uPostconditions then
2388 Set_Has_Postconditions (Current_Scope);
2389 Set_Debug_Info_Needed (Body_Id);
2392 -- Place subprogram on scope stack, and make formals visible. If there
2393 -- is a spec, the visible entity remains that of the spec.
2395 if Present (Spec_Id) then
2396 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
2398 if Is_Child_Unit (Spec_Id) then
2399 Generate_Reference (Spec_Id, Scope (Spec_Id), 'k', False);
2403 Style.Check_Identifier (Body_Id, Spec_Id);
2406 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
2407 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
2409 if Is_Abstract_Subprogram (Spec_Id) then
2410 Error_Msg_N ("an abstract subprogram cannot have a body", N);
2414 Set_Convention (Body_Id, Convention (Spec_Id));
2415 Set_Has_Completion (Spec_Id);
2417 if Is_Protected_Type (Scope (Spec_Id)) then
2418 Prot_Typ := Scope (Spec_Id);
2421 -- If this is a body generated for a renaming, do not check for
2422 -- full conformance. The check is redundant, because the spec of
2423 -- the body is a copy of the spec in the renaming declaration,
2424 -- and the test can lead to spurious errors on nested defaults.
2426 if Present (Spec_Decl)
2427 and then not Comes_From_Source (N)
2429 (Nkind (Original_Node (Spec_Decl)) =
2430 N_Subprogram_Renaming_Declaration
2431 or else (Present (Corresponding_Body (Spec_Decl))
2433 Nkind (Unit_Declaration_Node
2434 (Corresponding_Body (Spec_Decl))) =
2435 N_Subprogram_Renaming_Declaration))
2439 -- Conversely, the spec may have been generated for specless body
2440 -- with an inline pragma.
2442 elsif Comes_From_Source (N)
2443 and then not Comes_From_Source (Spec_Id)
2444 and then Has_Pragma_Inline (Spec_Id)
2451 Fully_Conformant, True, Conformant, Body_Id);
2454 -- If the body is not fully conformant, we have to decide if we
2455 -- should analyze it or not. If it has a really messed up profile
2456 -- then we probably should not analyze it, since we will get too
2457 -- many bogus messages.
2459 -- Our decision is to go ahead in the non-fully conformant case
2460 -- only if it is at least mode conformant with the spec. Note
2461 -- that the call to Check_Fully_Conformant has issued the proper
2462 -- error messages to complain about the lack of conformance.
2465 and then not Mode_Conformant (Body_Id, Spec_Id)
2471 if Spec_Id /= Body_Id then
2472 Reference_Body_Formals (Spec_Id, Body_Id);
2475 if Nkind (N) /= N_Subprogram_Body_Stub then
2476 Set_Corresponding_Spec (N, Spec_Id);
2478 -- Ada 2005 (AI-345): If the operation is a primitive operation
2479 -- of a concurrent type, the type of the first parameter has been
2480 -- replaced with the corresponding record, which is the proper
2481 -- run-time structure to use. However, within the body there may
2482 -- be uses of the formals that depend on primitive operations
2483 -- of the type (in particular calls in prefixed form) for which
2484 -- we need the original concurrent type. The operation may have
2485 -- several controlling formals, so the replacement must be done
2488 if Comes_From_Source (Spec_Id)
2489 and then Present (First_Entity (Spec_Id))
2490 and then Ekind (Etype (First_Entity (Spec_Id))) = E_Record_Type
2491 and then Is_Tagged_Type (Etype (First_Entity (Spec_Id)))
2493 Present (Interfaces (Etype (First_Entity (Spec_Id))))
2496 (Corresponding_Concurrent_Type
2497 (Etype (First_Entity (Spec_Id))))
2500 Typ : constant Entity_Id := Etype (First_Entity (Spec_Id));
2504 Form := First_Formal (Spec_Id);
2505 while Present (Form) loop
2506 if Etype (Form) = Typ then
2507 Set_Etype (Form, Corresponding_Concurrent_Type (Typ));
2515 -- Make the formals visible, and place subprogram on scope stack.
2516 -- This is also the point at which we set Last_Real_Spec_Entity
2517 -- to mark the entities which will not be moved to the body.
2519 Install_Formals (Spec_Id);
2520 Last_Real_Spec_Entity := Last_Entity (Spec_Id);
2521 Push_Scope (Spec_Id);
2523 -- Make sure that the subprogram is immediately visible. For
2524 -- child units that have no separate spec this is indispensable.
2525 -- Otherwise it is safe albeit redundant.
2527 Set_Is_Immediately_Visible (Spec_Id);
2530 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
2531 Set_Ekind (Body_Id, E_Subprogram_Body);
2532 Set_Scope (Body_Id, Scope (Spec_Id));
2533 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
2535 -- Case of subprogram body with no previous spec
2538 -- Check for style warning required
2542 -- Only apply check for source level subprograms for which checks
2543 -- have not been suppressed.
2545 and then Comes_From_Source (Body_Id)
2546 and then not Suppress_Style_Checks (Body_Id)
2548 -- No warnings within an instance
2550 and then not In_Instance
2552 -- No warnings for expression functions
2554 and then Nkind (Original_Node (N)) /= N_Expression_Function
2556 Style.Body_With_No_Spec (N);
2559 New_Overloaded_Entity (Body_Id);
2561 if Nkind (N) /= N_Subprogram_Body_Stub then
2562 Set_Acts_As_Spec (N);
2563 Generate_Definition (Body_Id);
2564 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
2566 (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True);
2567 Generate_Reference_To_Formals (Body_Id);
2568 Install_Formals (Body_Id);
2569 Push_Scope (Body_Id);
2573 -- If the return type is an anonymous access type whose designated type
2574 -- is the limited view of a class-wide type and the non-limited view is
2575 -- available, update the return type accordingly.
2577 if Ada_Version >= Ada_2005
2578 and then Comes_From_Source (N)
2585 Rtyp := Etype (Current_Scope);
2587 if Ekind (Rtyp) = E_Anonymous_Access_Type then
2588 Etyp := Directly_Designated_Type (Rtyp);
2590 if Is_Class_Wide_Type (Etyp)
2591 and then From_With_Type (Etyp)
2593 Set_Directly_Designated_Type
2594 (Etype (Current_Scope), Available_View (Etyp));
2600 -- If this is the proper body of a stub, we must verify that the stub
2601 -- conforms to the body, and to the previous spec if one was present.
2602 -- we know already that the body conforms to that spec. This test is
2603 -- only required for subprograms that come from source.
2605 if Nkind (Parent (N)) = N_Subunit
2606 and then Comes_From_Source (N)
2607 and then not Error_Posted (Body_Id)
2608 and then Nkind (Corresponding_Stub (Parent (N))) =
2609 N_Subprogram_Body_Stub
2612 Old_Id : constant Entity_Id :=
2614 (Specification (Corresponding_Stub (Parent (N))));
2616 Conformant : Boolean := False;
2619 if No (Spec_Id) then
2620 Check_Fully_Conformant (Body_Id, Old_Id);
2624 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
2626 if not Conformant then
2628 -- The stub was taken to be a new declaration. Indicate
2629 -- that it lacks a body.
2631 Set_Has_Completion (Old_Id, False);
2637 Set_Has_Completion (Body_Id);
2638 Check_Eliminated (Body_Id);
2640 if Nkind (N) = N_Subprogram_Body_Stub then
2643 elsif Present (Spec_Id)
2644 and then Expander_Active
2646 (Has_Pragma_Inline_Always (Spec_Id)
2647 or else (Has_Pragma_Inline (Spec_Id) and Front_End_Inlining))
2649 Build_Body_To_Inline (N, Spec_Id);
2652 -- Ada 2005 (AI-262): In library subprogram bodies, after the analysis
2653 -- if its specification we have to install the private withed units.
2654 -- This holds for child units as well.
2656 if Is_Compilation_Unit (Body_Id)
2657 or else Nkind (Parent (N)) = N_Compilation_Unit
2659 Install_Private_With_Clauses (Body_Id);
2662 Check_Anonymous_Return;
2664 -- Set the Protected_Formal field of each extra formal of the protected
2665 -- subprogram to reference the corresponding extra formal of the
2666 -- subprogram that implements it. For regular formals this occurs when
2667 -- the protected subprogram's declaration is expanded, but the extra
2668 -- formals don't get created until the subprogram is frozen. We need to
2669 -- do this before analyzing the protected subprogram's body so that any
2670 -- references to the original subprogram's extra formals will be changed
2671 -- refer to the implementing subprogram's formals (see Expand_Formal).
2673 if Present (Spec_Id)
2674 and then Is_Protected_Type (Scope (Spec_Id))
2675 and then Present (Protected_Body_Subprogram (Spec_Id))
2678 Impl_Subp : constant Entity_Id :=
2679 Protected_Body_Subprogram (Spec_Id);
2680 Prot_Ext_Formal : Entity_Id := Extra_Formals (Spec_Id);
2681 Impl_Ext_Formal : Entity_Id := Extra_Formals (Impl_Subp);
2683 while Present (Prot_Ext_Formal) loop
2684 pragma Assert (Present (Impl_Ext_Formal));
2685 Set_Protected_Formal (Prot_Ext_Formal, Impl_Ext_Formal);
2686 Next_Formal_With_Extras (Prot_Ext_Formal);
2687 Next_Formal_With_Extras (Impl_Ext_Formal);
2692 -- Now we can go on to analyze the body
2694 HSS := Handled_Statement_Sequence (N);
2695 Set_Actual_Subtypes (N, Current_Scope);
2697 -- Deal with preconditions and postconditions. In formal verification
2698 -- mode, we keep pre- and postconditions attached to entities rather
2699 -- than inserted in the code, in order to facilitate a distinct
2700 -- treatment for them.
2702 if not Alfa_Mode then
2703 Process_PPCs (N, Spec_Id, Body_Id);
2706 -- Add a declaration for the Protection object, renaming declarations
2707 -- for discriminals and privals and finally a declaration for the entry
2708 -- family index (if applicable). This form of early expansion is done
2709 -- when the Expander is active because Install_Private_Data_Declarations
2710 -- references entities which were created during regular expansion.
2712 if Full_Expander_Active
2713 and then Comes_From_Source (N)
2714 and then Present (Prot_Typ)
2715 and then Present (Spec_Id)
2716 and then not Is_Eliminated (Spec_Id)
2718 Install_Private_Data_Declarations
2719 (Sloc (N), Spec_Id, Prot_Typ, N, Declarations (N));
2722 -- Analyze the declarations (this call will analyze the precondition
2723 -- Check pragmas we prepended to the list, as well as the declaration
2724 -- of the _Postconditions procedure).
2726 Analyze_Declarations (Declarations (N));
2728 -- Check completion, and analyze the statements
2731 Inspect_Deferred_Constant_Completion (Declarations (N));
2734 -- Deal with end of scope processing for the body
2736 Process_End_Label (HSS, 't', Current_Scope);
2738 Check_Subprogram_Order (N);
2739 Set_Analyzed (Body_Id);
2741 -- If we have a separate spec, then the analysis of the declarations
2742 -- caused the entities in the body to be chained to the spec id, but
2743 -- we want them chained to the body id. Only the formal parameters
2744 -- end up chained to the spec id in this case.
2746 if Present (Spec_Id) then
2748 -- We must conform to the categorization of our spec
2750 Validate_Categorization_Dependency (N, Spec_Id);
2752 -- And if this is a child unit, the parent units must conform
2754 if Is_Child_Unit (Spec_Id) then
2755 Validate_Categorization_Dependency
2756 (Unit_Declaration_Node (Spec_Id), Spec_Id);
2759 -- Here is where we move entities from the spec to the body
2761 -- Case where there are entities that stay with the spec
2763 if Present (Last_Real_Spec_Entity) then
2765 -- No body entities (happens when the only real spec entities
2766 -- come from precondition and postcondition pragmas)
2768 if No (Last_Entity (Body_Id)) then
2770 (Body_Id, Next_Entity (Last_Real_Spec_Entity));
2772 -- Body entities present (formals), so chain stuff past them
2776 (Last_Entity (Body_Id), Next_Entity (Last_Real_Spec_Entity));
2779 Set_Next_Entity (Last_Real_Spec_Entity, Empty);
2780 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2781 Set_Last_Entity (Spec_Id, Last_Real_Spec_Entity);
2783 -- Case where there are no spec entities, in this case there can
2784 -- be no body entities either, so just move everything.
2787 pragma Assert (No (Last_Entity (Body_Id)));
2788 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
2789 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
2790 Set_First_Entity (Spec_Id, Empty);
2791 Set_Last_Entity (Spec_Id, Empty);
2795 Check_Missing_Return;
2797 -- Now we are going to check for variables that are never modified in
2798 -- the body of the procedure. But first we deal with a special case
2799 -- where we want to modify this check. If the body of the subprogram
2800 -- starts with a raise statement or its equivalent, or if the body
2801 -- consists entirely of a null statement, then it is pretty obvious
2802 -- that it is OK to not reference the parameters. For example, this
2803 -- might be the following common idiom for a stubbed function:
2804 -- statement of the procedure raises an exception. In particular this
2805 -- deals with the common idiom of a stubbed function, which might
2806 -- appear as something like
2808 -- function F (A : Integer) return Some_Type;
2811 -- raise Program_Error;
2815 -- Here the purpose of X is simply to satisfy the annoying requirement
2816 -- in Ada that there be at least one return, and we certainly do not
2817 -- want to go posting warnings on X that it is not initialized! On
2818 -- the other hand, if X is entirely unreferenced that should still
2821 -- What we do is to detect these cases, and if we find them, flag the
2822 -- subprogram as being Is_Trivial_Subprogram and then use that flag to
2823 -- suppress unwanted warnings. For the case of the function stub above
2824 -- we have a special test to set X as apparently assigned to suppress
2831 -- Skip initial labels (for one thing this occurs when we are in
2832 -- front end ZCX mode, but in any case it is irrelevant), and also
2833 -- initial Push_xxx_Error_Label nodes, which are also irrelevant.
2835 Stm := First (Statements (HSS));
2836 while Nkind (Stm) = N_Label
2837 or else Nkind (Stm) in N_Push_xxx_Label
2842 -- Do the test on the original statement before expansion
2845 Ostm : constant Node_Id := Original_Node (Stm);
2848 -- If explicit raise statement, turn on flag
2850 if Nkind (Ostm) = N_Raise_Statement then
2851 Set_Trivial_Subprogram (Stm);
2853 -- If null statement, and no following statements, turn on flag
2855 elsif Nkind (Stm) = N_Null_Statement
2856 and then Comes_From_Source (Stm)
2857 and then No (Next (Stm))
2859 Set_Trivial_Subprogram (Stm);
2861 -- Check for explicit call cases which likely raise an exception
2863 elsif Nkind (Ostm) = N_Procedure_Call_Statement then
2864 if Is_Entity_Name (Name (Ostm)) then
2866 Ent : constant Entity_Id := Entity (Name (Ostm));
2869 -- If the procedure is marked No_Return, then likely it
2870 -- raises an exception, but in any case it is not coming
2871 -- back here, so turn on the flag.
2874 and then Ekind (Ent) = E_Procedure
2875 and then No_Return (Ent)
2877 Set_Trivial_Subprogram (Stm);
2885 -- Check for variables that are never modified
2891 -- If there is a separate spec, then transfer Never_Set_In_Source
2892 -- flags from out parameters to the corresponding entities in the
2893 -- body. The reason we do that is we want to post error flags on
2894 -- the body entities, not the spec entities.
2896 if Present (Spec_Id) then
2897 E1 := First_Entity (Spec_Id);
2898 while Present (E1) loop
2899 if Ekind (E1) = E_Out_Parameter then
2900 E2 := First_Entity (Body_Id);
2901 while Present (E2) loop
2902 exit when Chars (E1) = Chars (E2);
2906 if Present (E2) then
2907 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
2915 -- Check references in body unless it was deleted. Note that the
2916 -- check of Body_Deleted here is not just for efficiency, it is
2917 -- necessary to avoid junk warnings on formal parameters.
2919 if not Body_Deleted then
2920 Check_References (Body_Id);
2923 end Analyze_Subprogram_Body_Helper;
2925 ------------------------------------
2926 -- Analyze_Subprogram_Declaration --
2927 ------------------------------------
2929 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
2930 Loc : constant Source_Ptr := Sloc (N);
2931 Scop : constant Entity_Id := Current_Scope;
2932 Designator : Entity_Id;
2934 Null_Body : Node_Id := Empty;
2936 -- Start of processing for Analyze_Subprogram_Declaration
2939 -- Null procedures are not allowed in SPARK
2941 if Nkind (Specification (N)) = N_Procedure_Specification
2942 and then Null_Present (Specification (N))
2944 Check_SPARK_Restriction ("null procedure is not allowed", N);
2947 -- For a null procedure, capture the profile before analysis, for
2948 -- expansion at the freeze point and at each point of call. The body
2949 -- will only be used if the procedure has preconditions. In that case
2950 -- the body is analyzed at the freeze point.
2952 if Nkind (Specification (N)) = N_Procedure_Specification
2953 and then Null_Present (Specification (N))
2954 and then Expander_Active
2957 Make_Subprogram_Body (Loc,
2959 New_Copy_Tree (Specification (N)),
2962 Handled_Statement_Sequence =>
2963 Make_Handled_Sequence_Of_Statements (Loc,
2964 Statements => New_List (Make_Null_Statement (Loc))));
2966 -- Create new entities for body and formals
2968 Set_Defining_Unit_Name (Specification (Null_Body),
2969 Make_Defining_Identifier (Loc, Chars (Defining_Entity (N))));
2970 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
2972 Form := First (Parameter_Specifications (Specification (Null_Body)));
2973 while Present (Form) loop
2974 Set_Defining_Identifier (Form,
2975 Make_Defining_Identifier (Loc,
2976 Chars (Defining_Identifier (Form))));
2978 -- Resolve the types of the formals now, because the freeze point
2979 -- may appear in a different context, e.g. an instantiation.
2981 if Nkind (Parameter_Type (Form)) /= N_Access_Definition then
2982 Find_Type (Parameter_Type (Form));
2985 No (Access_To_Subprogram_Definition (Parameter_Type (Form)))
2987 Find_Type (Subtype_Mark (Parameter_Type (Form)));
2991 -- the case of a null procedure with a formal that is an
2992 -- access_to_subprogram type, and that is used as an actual
2993 -- in an instantiation is left to the enthusiastic reader.
3001 if Is_Protected_Type (Current_Scope) then
3002 Error_Msg_N ("protected operation cannot be a null procedure", N);
3006 Designator := Analyze_Subprogram_Specification (Specification (N));
3007 Generate_Definition (Designator);
3008 -- ??? why this call, already in Analyze_Subprogram_Specification
3010 if Debug_Flag_C then
3011 Write_Str ("==> subprogram spec ");
3012 Write_Name (Chars (Designator));
3013 Write_Str (" from ");
3014 Write_Location (Sloc (N));
3019 if Nkind (Specification (N)) = N_Procedure_Specification
3020 and then Null_Present (Specification (N))
3022 Set_Has_Completion (Designator);
3024 if Present (Null_Body) then
3025 Set_Corresponding_Body (N, Defining_Entity (Null_Body));
3026 Set_Body_To_Inline (N, Null_Body);
3027 Set_Is_Inlined (Designator);
3031 Validate_RCI_Subprogram_Declaration (N);
3032 New_Overloaded_Entity (Designator);
3033 Check_Delayed_Subprogram (Designator);
3035 -- If the type of the first formal of the current subprogram is a
3036 -- nongeneric tagged private type, mark the subprogram as being a
3037 -- private primitive. Ditto if this is a function with controlling
3038 -- result, and the return type is currently private. In both cases,
3039 -- the type of the controlling argument or result must be in the
3040 -- current scope for the operation to be primitive.
3042 if Has_Controlling_Result (Designator)
3043 and then Is_Private_Type (Etype (Designator))
3044 and then Scope (Etype (Designator)) = Current_Scope
3045 and then not Is_Generic_Actual_Type (Etype (Designator))
3047 Set_Is_Private_Primitive (Designator);
3049 elsif Present (First_Formal (Designator)) then
3051 Formal_Typ : constant Entity_Id :=
3052 Etype (First_Formal (Designator));
3054 Set_Is_Private_Primitive (Designator,
3055 Is_Tagged_Type (Formal_Typ)
3056 and then Scope (Formal_Typ) = Current_Scope
3057 and then Is_Private_Type (Formal_Typ)
3058 and then not Is_Generic_Actual_Type (Formal_Typ));
3062 -- Ada 2005 (AI-251): Abstract interface primitives must be abstract
3065 if Ada_Version >= Ada_2005
3066 and then Comes_From_Source (N)
3067 and then Is_Dispatching_Operation (Designator)
3074 if Has_Controlling_Result (Designator) then
3075 Etyp := Etype (Designator);
3078 E := First_Entity (Designator);
3080 and then Is_Formal (E)
3081 and then not Is_Controlling_Formal (E)
3089 if Is_Access_Type (Etyp) then
3090 Etyp := Directly_Designated_Type (Etyp);
3093 if Is_Interface (Etyp)
3094 and then not Is_Abstract_Subprogram (Designator)
3095 and then not (Ekind (Designator) = E_Procedure
3096 and then Null_Present (Specification (N)))
3098 Error_Msg_Name_1 := Chars (Defining_Entity (N));
3100 ("(Ada 2005) interface subprogram % must be abstract or null",
3106 -- What is the following code for, it used to be
3108 -- ??? Set_Suppress_Elaboration_Checks
3109 -- ??? (Designator, Elaboration_Checks_Suppressed (Designator));
3111 -- The following seems equivalent, but a bit dubious
3113 if Elaboration_Checks_Suppressed (Designator) then
3114 Set_Kill_Elaboration_Checks (Designator);
3117 if Scop /= Standard_Standard
3118 and then not Is_Child_Unit (Designator)
3120 Set_Categorization_From_Scope (Designator, Scop);
3122 -- For a compilation unit, check for library-unit pragmas
3124 Push_Scope (Designator);
3125 Set_Categorization_From_Pragmas (N);
3126 Validate_Categorization_Dependency (N, Designator);
3130 -- For a compilation unit, set body required. This flag will only be
3131 -- reset if a valid Import or Interface pragma is processed later on.
3133 if Nkind (Parent (N)) = N_Compilation_Unit then
3134 Set_Body_Required (Parent (N), True);
3136 if Ada_Version >= Ada_2005
3137 and then Nkind (Specification (N)) = N_Procedure_Specification
3138 and then Null_Present (Specification (N))
3141 ("null procedure cannot be declared at library level", N);
3145 Generate_Reference_To_Formals (Designator);
3146 Check_Eliminated (Designator);
3148 if Debug_Flag_C then
3150 Write_Str ("<== subprogram spec ");
3151 Write_Name (Chars (Designator));
3152 Write_Str (" from ");
3153 Write_Location (Sloc (N));
3157 if Is_Protected_Type (Current_Scope) then
3159 -- Indicate that this is a protected operation, because it may be
3160 -- used in subsequent declarations within the protected type.
3162 Set_Convention (Designator, Convention_Protected);
3165 List_Inherited_Pre_Post_Aspects (Designator);
3167 if Has_Aspects (N) then
3168 Analyze_Aspect_Specifications (N, Designator);
3170 end Analyze_Subprogram_Declaration;
3172 --------------------------------------
3173 -- Analyze_Subprogram_Specification --
3174 --------------------------------------
3176 -- Reminder: N here really is a subprogram specification (not a subprogram
3177 -- declaration). This procedure is called to analyze the specification in
3178 -- both subprogram bodies and subprogram declarations (specs).
3180 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is
3181 Designator : constant Entity_Id := Defining_Entity (N);
3182 Formals : constant List_Id := Parameter_Specifications (N);
3184 -- Start of processing for Analyze_Subprogram_Specification
3187 -- User-defined operator is not allowed in SPARK, except as a renaming
3189 if Nkind (Defining_Unit_Name (N)) = N_Defining_Operator_Symbol
3190 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
3192 Check_SPARK_Restriction ("user-defined operator is not allowed", N);
3195 -- Proceed with analysis
3197 Generate_Definition (Designator);
3198 Set_Contract (Designator, Make_Contract (Sloc (Designator)));
3200 if Nkind (N) = N_Function_Specification then
3201 Set_Ekind (Designator, E_Function);
3202 Set_Mechanism (Designator, Default_Mechanism);
3204 Set_Ekind (Designator, E_Procedure);
3205 Set_Etype (Designator, Standard_Void_Type);
3208 -- Introduce new scope for analysis of the formals and the return type
3210 Set_Scope (Designator, Current_Scope);
3212 if Present (Formals) then
3213 Push_Scope (Designator);
3214 Process_Formals (Formals, N);
3216 -- Ada 2005 (AI-345): If this is an overriding operation of an
3217 -- inherited interface operation, and the controlling type is
3218 -- a synchronized type, replace the type with its corresponding
3219 -- record, to match the proper signature of an overriding operation.
3220 -- Same processing for an access parameter whose designated type is
3221 -- derived from a synchronized interface.
3223 if Ada_Version >= Ada_2005 then
3226 Formal_Typ : Entity_Id;
3227 Rec_Typ : Entity_Id;
3228 Desig_Typ : Entity_Id;
3231 Formal := First_Formal (Designator);
3232 while Present (Formal) loop
3233 Formal_Typ := Etype (Formal);
3235 if Is_Concurrent_Type (Formal_Typ)
3236 and then Present (Corresponding_Record_Type (Formal_Typ))
3238 Rec_Typ := Corresponding_Record_Type (Formal_Typ);
3240 if Present (Interfaces (Rec_Typ)) then
3241 Set_Etype (Formal, Rec_Typ);
3244 elsif Ekind (Formal_Typ) = E_Anonymous_Access_Type then
3245 Desig_Typ := Designated_Type (Formal_Typ);
3247 if Is_Concurrent_Type (Desig_Typ)
3248 and then Present (Corresponding_Record_Type (Desig_Typ))
3250 Rec_Typ := Corresponding_Record_Type (Desig_Typ);
3252 if Present (Interfaces (Rec_Typ)) then
3253 Set_Directly_Designated_Type (Formal_Typ, Rec_Typ);
3258 Next_Formal (Formal);
3265 -- The subprogram scope is pushed and popped around the processing of
3266 -- the return type for consistency with call above to Process_Formals
3267 -- (which itself can call Analyze_Return_Type), and to ensure that any
3268 -- itype created for the return type will be associated with the proper
3271 elsif Nkind (N) = N_Function_Specification then
3272 Push_Scope (Designator);
3273 Analyze_Return_Type (N);
3279 if Nkind (N) = N_Function_Specification then
3281 -- Deal with operator symbol case
3283 if Nkind (Designator) = N_Defining_Operator_Symbol then
3284 Valid_Operator_Definition (Designator);
3287 May_Need_Actuals (Designator);
3289 -- Ada 2005 (AI-251): If the return type is abstract, verify that
3290 -- the subprogram is abstract also. This does not apply to renaming
3291 -- declarations, where abstractness is inherited.
3293 -- In case of primitives associated with abstract interface types
3294 -- the check is applied later (see Analyze_Subprogram_Declaration).
3296 if not Nkind_In (Parent (N), N_Subprogram_Renaming_Declaration,
3297 N_Abstract_Subprogram_Declaration,
3298 N_Formal_Abstract_Subprogram_Declaration)
3300 if Is_Abstract_Type (Etype (Designator))
3301 and then not Is_Interface (Etype (Designator))
3304 ("function that returns abstract type must be abstract", N);
3306 -- Ada 2012 (AI-0073): Extend this test to subprograms with an
3307 -- access result whose designated type is abstract.
3309 elsif Nkind (Result_Definition (N)) = N_Access_Definition
3311 not Is_Class_Wide_Type (Designated_Type (Etype (Designator)))
3312 and then Is_Abstract_Type (Designated_Type (Etype (Designator)))
3313 and then Ada_Version >= Ada_2012
3315 Error_Msg_N ("function whose access result designates "
3316 & "abstract type must be abstract", N);
3322 end Analyze_Subprogram_Specification;
3324 --------------------------
3325 -- Build_Body_To_Inline --
3326 --------------------------
3328 procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is
3329 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
3330 Original_Body : Node_Id;
3331 Body_To_Analyze : Node_Id;
3332 Max_Size : constant := 10;
3333 Stat_Count : Integer := 0;
3335 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
3336 -- Check for declarations that make inlining not worthwhile
3338 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
3339 -- Check for statements that make inlining not worthwhile: any tasking
3340 -- statement, nested at any level. Keep track of total number of
3341 -- elementary statements, as a measure of acceptable size.
3343 function Has_Pending_Instantiation return Boolean;
3344 -- If some enclosing body contains instantiations that appear before the
3345 -- corresponding generic body, the enclosing body has a freeze node so
3346 -- that it can be elaborated after the generic itself. This might
3347 -- conflict with subsequent inlinings, so that it is unsafe to try to
3348 -- inline in such a case.
3350 function Has_Single_Return return Boolean;
3351 -- In general we cannot inline functions that return unconstrained type.
3352 -- However, we can handle such functions if all return statements return
3353 -- a local variable that is the only declaration in the body of the
3354 -- function. In that case the call can be replaced by that local
3355 -- variable as is done for other inlined calls.
3357 procedure Remove_Pragmas;
3358 -- A pragma Unreferenced or pragma Unmodified that mentions a formal
3359 -- parameter has no meaning when the body is inlined and the formals
3360 -- are rewritten. Remove it from body to inline. The analysis of the
3361 -- non-inlined body will handle the pragma properly.
3363 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean;
3364 -- If the body of the subprogram includes a call that returns an
3365 -- unconstrained type, the secondary stack is involved, and it
3366 -- is not worth inlining.
3368 ------------------------------
3369 -- Has_Excluded_Declaration --
3370 ------------------------------
3372 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
3375 function Is_Unchecked_Conversion (D : Node_Id) return Boolean;
3376 -- Nested subprograms make a given body ineligible for inlining, but
3377 -- we make an exception for instantiations of unchecked conversion.
3378 -- The body has not been analyzed yet, so check the name, and verify
3379 -- that the visible entity with that name is the predefined unit.
3381 -----------------------------
3382 -- Is_Unchecked_Conversion --
3383 -----------------------------
3385 function Is_Unchecked_Conversion (D : Node_Id) return Boolean is
3386 Id : constant Node_Id := Name (D);
3390 if Nkind (Id) = N_Identifier
3391 and then Chars (Id) = Name_Unchecked_Conversion
3393 Conv := Current_Entity (Id);
3395 elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name)
3396 and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion
3398 Conv := Current_Entity (Selector_Name (Id));
3403 return Present (Conv)
3404 and then Is_Predefined_File_Name
3405 (Unit_File_Name (Get_Source_Unit (Conv)))
3406 and then Is_Intrinsic_Subprogram (Conv);
3407 end Is_Unchecked_Conversion;
3409 -- Start of processing for Has_Excluded_Declaration
3413 while Present (D) loop
3414 if (Nkind (D) = N_Function_Instantiation
3415 and then not Is_Unchecked_Conversion (D))
3416 or else Nkind_In (D, N_Protected_Type_Declaration,
3417 N_Package_Declaration,
3418 N_Package_Instantiation,
3420 N_Procedure_Instantiation,
3421 N_Task_Type_Declaration)
3424 ("cannot inline & (non-allowed declaration)?", D, Subp);
3432 end Has_Excluded_Declaration;
3434 ----------------------------
3435 -- Has_Excluded_Statement --
3436 ----------------------------
3438 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
3444 while Present (S) loop
3445 Stat_Count := Stat_Count + 1;
3447 if Nkind_In (S, N_Abort_Statement,
3448 N_Asynchronous_Select,
3449 N_Conditional_Entry_Call,
3450 N_Delay_Relative_Statement,
3451 N_Delay_Until_Statement,
3456 ("cannot inline & (non-allowed statement)?", S, Subp);
3459 elsif Nkind (S) = N_Block_Statement then
3460 if Present (Declarations (S))
3461 and then Has_Excluded_Declaration (Declarations (S))
3465 elsif Present (Handled_Statement_Sequence (S))
3468 (Exception_Handlers (Handled_Statement_Sequence (S)))
3470 Has_Excluded_Statement
3471 (Statements (Handled_Statement_Sequence (S))))
3476 elsif Nkind (S) = N_Case_Statement then
3477 E := First (Alternatives (S));
3478 while Present (E) loop
3479 if Has_Excluded_Statement (Statements (E)) then
3486 elsif Nkind (S) = N_If_Statement then
3487 if Has_Excluded_Statement (Then_Statements (S)) then
3491 if Present (Elsif_Parts (S)) then
3492 E := First (Elsif_Parts (S));
3493 while Present (E) loop
3494 if Has_Excluded_Statement (Then_Statements (E)) then
3501 if Present (Else_Statements (S))
3502 and then Has_Excluded_Statement (Else_Statements (S))
3507 elsif Nkind (S) = N_Loop_Statement
3508 and then Has_Excluded_Statement (Statements (S))
3512 elsif Nkind (S) = N_Extended_Return_Statement then
3513 if Has_Excluded_Statement
3514 (Statements (Handled_Statement_Sequence (S)))
3516 (Exception_Handlers (Handled_Statement_Sequence (S)))
3526 end Has_Excluded_Statement;
3528 -------------------------------
3529 -- Has_Pending_Instantiation --
3530 -------------------------------
3532 function Has_Pending_Instantiation return Boolean is
3537 while Present (S) loop
3538 if Is_Compilation_Unit (S)
3539 or else Is_Child_Unit (S)
3543 elsif Ekind (S) = E_Package
3544 and then Has_Forward_Instantiation (S)
3553 end Has_Pending_Instantiation;
3555 ------------------------
3556 -- Has_Single_Return --
3557 ------------------------
3559 function Has_Single_Return return Boolean is
3560 Return_Statement : Node_Id := Empty;
3562 function Check_Return (N : Node_Id) return Traverse_Result;
3568 function Check_Return (N : Node_Id) return Traverse_Result is
3570 if Nkind (N) = N_Simple_Return_Statement then
3571 if Present (Expression (N))
3572 and then Is_Entity_Name (Expression (N))
3574 if No (Return_Statement) then
3575 Return_Statement := N;
3578 elsif Chars (Expression (N)) =
3579 Chars (Expression (Return_Statement))
3587 -- A return statement within an extended return is a noop
3590 elsif No (Expression (N))
3591 and then Nkind (Parent (Parent (N))) =
3592 N_Extended_Return_Statement
3597 -- Expression has wrong form
3602 -- We can only inline a build-in-place function if
3603 -- it has a single extended return.
3605 elsif Nkind (N) = N_Extended_Return_Statement then
3606 if No (Return_Statement) then
3607 Return_Statement := N;
3619 function Check_All_Returns is new Traverse_Func (Check_Return);
3621 -- Start of processing for Has_Single_Return
3624 if Check_All_Returns (N) /= OK then
3627 elsif Nkind (Return_Statement) = N_Extended_Return_Statement then
3631 return Present (Declarations (N))
3632 and then Present (First (Declarations (N)))
3633 and then Chars (Expression (Return_Statement)) =
3634 Chars (Defining_Identifier (First (Declarations (N))));
3636 end Has_Single_Return;
3638 --------------------
3639 -- Remove_Pragmas --
3640 --------------------
3642 procedure Remove_Pragmas is
3647 Decl := First (Declarations (Body_To_Analyze));
3648 while Present (Decl) loop
3651 if Nkind (Decl) = N_Pragma
3652 and then (Pragma_Name (Decl) = Name_Unreferenced
3654 Pragma_Name (Decl) = Name_Unmodified)
3663 --------------------------
3664 -- Uses_Secondary_Stack --
3665 --------------------------
3667 function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is
3668 function Check_Call (N : Node_Id) return Traverse_Result;
3669 -- Look for function calls that return an unconstrained type
3675 function Check_Call (N : Node_Id) return Traverse_Result is
3677 if Nkind (N) = N_Function_Call
3678 and then Is_Entity_Name (Name (N))
3679 and then Is_Composite_Type (Etype (Entity (Name (N))))
3680 and then not Is_Constrained (Etype (Entity (Name (N))))
3683 ("cannot inline & (call returns unconstrained type)?",
3691 function Check_Calls is new Traverse_Func (Check_Call);
3694 return Check_Calls (Bod) = Abandon;
3695 end Uses_Secondary_Stack;
3697 -- Start of processing for Build_Body_To_Inline
3700 -- Return immediately if done already
3702 if Nkind (Decl) = N_Subprogram_Declaration
3703 and then Present (Body_To_Inline (Decl))
3707 -- Functions that return unconstrained composite types require
3708 -- secondary stack handling, and cannot currently be inlined, unless
3709 -- all return statements return a local variable that is the first
3710 -- local declaration in the body.
3712 elsif Ekind (Subp) = E_Function
3713 and then not Is_Scalar_Type (Etype (Subp))
3714 and then not Is_Access_Type (Etype (Subp))
3715 and then not Is_Constrained (Etype (Subp))
3717 if not Has_Single_Return then
3719 ("cannot inline & (unconstrained return type)?", N, Subp);
3723 -- Ditto for functions that return controlled types, where controlled
3724 -- actions interfere in complex ways with inlining.
3726 elsif Ekind (Subp) = E_Function
3727 and then Needs_Finalization (Etype (Subp))
3730 ("cannot inline & (controlled return type)?", N, Subp);
3734 if Present (Declarations (N))
3735 and then Has_Excluded_Declaration (Declarations (N))
3740 if Present (Handled_Statement_Sequence (N)) then
3741 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
3743 ("cannot inline& (exception handler)?",
3744 First (Exception_Handlers (Handled_Statement_Sequence (N))),
3748 Has_Excluded_Statement
3749 (Statements (Handled_Statement_Sequence (N)))
3755 -- We do not inline a subprogram that is too large, unless it is
3756 -- marked Inline_Always. This pragma does not suppress the other
3757 -- checks on inlining (forbidden declarations, handlers, etc).
3759 if Stat_Count > Max_Size
3760 and then not Has_Pragma_Inline_Always (Subp)
3762 Cannot_Inline ("cannot inline& (body too large)?", N, Subp);
3766 if Has_Pending_Instantiation then
3768 ("cannot inline& (forward instance within enclosing body)?",
3773 -- Within an instance, the body to inline must be treated as a nested
3774 -- generic, so that the proper global references are preserved.
3776 -- Note that we do not do this at the library level, because it is not
3777 -- needed, and furthermore this causes trouble if front end inlining
3778 -- is activated (-gnatN).
3780 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3781 Save_Env (Scope (Current_Scope), Scope (Current_Scope));
3782 Original_Body := Copy_Generic_Node (N, Empty, True);
3784 Original_Body := Copy_Separate_Tree (N);
3787 -- We need to capture references to the formals in order to substitute
3788 -- the actuals at the point of inlining, i.e. instantiation. To treat
3789 -- the formals as globals to the body to inline, we nest it within
3790 -- a dummy parameterless subprogram, declared within the real one.
3791 -- To avoid generating an internal name (which is never public, and
3792 -- which affects serial numbers of other generated names), we use
3793 -- an internal symbol that cannot conflict with user declarations.
3795 Set_Parameter_Specifications (Specification (Original_Body), No_List);
3796 Set_Defining_Unit_Name
3797 (Specification (Original_Body),
3798 Make_Defining_Identifier (Sloc (N), Name_uParent));
3799 Set_Corresponding_Spec (Original_Body, Empty);
3801 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
3803 -- Set return type of function, which is also global and does not need
3806 if Ekind (Subp) = E_Function then
3807 Set_Result_Definition (Specification (Body_To_Analyze),
3808 New_Occurrence_Of (Etype (Subp), Sloc (N)));
3811 if No (Declarations (N)) then
3812 Set_Declarations (N, New_List (Body_To_Analyze));
3814 Append (Body_To_Analyze, Declarations (N));
3817 Expander_Mode_Save_And_Set (False);
3820 Analyze (Body_To_Analyze);
3821 Push_Scope (Defining_Entity (Body_To_Analyze));
3822 Save_Global_References (Original_Body);
3824 Remove (Body_To_Analyze);
3826 Expander_Mode_Restore;
3828 -- Restore environment if previously saved
3830 if In_Instance and then Scope (Current_Scope) /= Standard_Standard then
3834 -- If secondary stk used there is no point in inlining. We have
3835 -- already issued the warning in this case, so nothing to do.
3837 if Uses_Secondary_Stack (Body_To_Analyze) then
3841 Set_Body_To_Inline (Decl, Original_Body);
3842 Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp));
3843 Set_Is_Inlined (Subp);
3844 end Build_Body_To_Inline;
3850 procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is
3852 -- Do not emit warning if this is a predefined unit which is not the
3853 -- main unit. With validity checks enabled, some predefined subprograms
3854 -- may contain nested subprograms and become ineligible for inlining.
3856 if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp)))
3857 and then not In_Extended_Main_Source_Unit (Subp)
3861 elsif Has_Pragma_Inline_Always (Subp) then
3863 -- Remove last character (question mark) to make this into an error,
3864 -- because the Inline_Always pragma cannot be obeyed.
3866 Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp);
3868 elsif Ineffective_Inline_Warnings then
3869 Error_Msg_NE (Msg, N, Subp);
3873 -----------------------
3874 -- Check_Conformance --
3875 -----------------------
3877 procedure Check_Conformance
3878 (New_Id : Entity_Id;
3880 Ctype : Conformance_Type;
3882 Conforms : out Boolean;
3883 Err_Loc : Node_Id := Empty;
3884 Get_Inst : Boolean := False;
3885 Skip_Controlling_Formals : Boolean := False)
3887 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
3888 -- Sets Conforms to False. If Errmsg is False, then that's all it does.
3889 -- If Errmsg is True, then processing continues to post an error message
3890 -- for conformance error on given node. Two messages are output. The
3891 -- first message points to the previous declaration with a general "no
3892 -- conformance" message. The second is the detailed reason, supplied as
3893 -- Msg. The parameter N provide information for a possible & insertion
3894 -- in the message, and also provides the location for posting the
3895 -- message in the absence of a specified Err_Loc location.
3897 -----------------------
3898 -- Conformance_Error --
3899 -----------------------
3901 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
3908 if No (Err_Loc) then
3914 Error_Msg_Sloc := Sloc (Old_Id);
3917 when Type_Conformant =>
3918 Error_Msg_N -- CODEFIX
3919 ("not type conformant with declaration#!", Enode);
3921 when Mode_Conformant =>
3922 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3924 ("not mode conformant with operation inherited#!",
3928 ("not mode conformant with declaration#!", Enode);
3931 when Subtype_Conformant =>
3932 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3934 ("not subtype conformant with operation inherited#!",
3938 ("not subtype conformant with declaration#!", Enode);
3941 when Fully_Conformant =>
3942 if Nkind (Parent (Old_Id)) = N_Full_Type_Declaration then
3943 Error_Msg_N -- CODEFIX
3944 ("not fully conformant with operation inherited#!",
3947 Error_Msg_N -- CODEFIX
3948 ("not fully conformant with declaration#!", Enode);
3952 Error_Msg_NE (Msg, Enode, N);
3954 end Conformance_Error;
3958 Old_Type : constant Entity_Id := Etype (Old_Id);
3959 New_Type : constant Entity_Id := Etype (New_Id);
3960 Old_Formal : Entity_Id;
3961 New_Formal : Entity_Id;
3962 Access_Types_Match : Boolean;
3963 Old_Formal_Base : Entity_Id;
3964 New_Formal_Base : Entity_Id;
3966 -- Start of processing for Check_Conformance
3971 -- We need a special case for operators, since they don't appear
3974 if Ctype = Type_Conformant then
3975 if Ekind (New_Id) = E_Operator
3976 and then Operator_Matches_Spec (New_Id, Old_Id)
3982 -- If both are functions/operators, check return types conform
3984 if Old_Type /= Standard_Void_Type
3985 and then New_Type /= Standard_Void_Type
3988 -- If we are checking interface conformance we omit controlling
3989 -- arguments and result, because we are only checking the conformance
3990 -- of the remaining parameters.
3992 if Has_Controlling_Result (Old_Id)
3993 and then Has_Controlling_Result (New_Id)
3994 and then Skip_Controlling_Formals
3998 elsif not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
3999 Conformance_Error ("\return type does not match!", New_Id);
4003 -- Ada 2005 (AI-231): In case of anonymous access types check the
4004 -- null-exclusion and access-to-constant attributes match.
4006 if Ada_Version >= Ada_2005
4007 and then Ekind (Etype (Old_Type)) = E_Anonymous_Access_Type
4009 (Can_Never_Be_Null (Old_Type)
4010 /= Can_Never_Be_Null (New_Type)
4011 or else Is_Access_Constant (Etype (Old_Type))
4012 /= Is_Access_Constant (Etype (New_Type)))
4014 Conformance_Error ("\return type does not match!", New_Id);
4018 -- If either is a function/operator and the other isn't, error
4020 elsif Old_Type /= Standard_Void_Type
4021 or else New_Type /= Standard_Void_Type
4023 Conformance_Error ("\functions can only match functions!", New_Id);
4027 -- In subtype conformant case, conventions must match (RM 6.3.1(16)).
4028 -- If this is a renaming as body, refine error message to indicate that
4029 -- the conflict is with the original declaration. If the entity is not
4030 -- frozen, the conventions don't have to match, the one of the renamed
4031 -- entity is inherited.
4033 if Ctype >= Subtype_Conformant then
4034 if Convention (Old_Id) /= Convention (New_Id) then
4036 if not Is_Frozen (New_Id) then
4039 elsif Present (Err_Loc)
4040 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
4041 and then Present (Corresponding_Spec (Err_Loc))
4043 Error_Msg_Name_1 := Chars (New_Id);
4045 Name_Ada + Convention_Id'Pos (Convention (New_Id));
4046 Conformance_Error ("\prior declaration for% has convention %!");
4049 Conformance_Error ("\calling conventions do not match!");
4054 elsif Is_Formal_Subprogram (Old_Id)
4055 or else Is_Formal_Subprogram (New_Id)
4057 Conformance_Error ("\formal subprograms not allowed!");
4062 -- Deal with parameters
4064 -- Note: we use the entity information, rather than going directly
4065 -- to the specification in the tree. This is not only simpler, but
4066 -- absolutely necessary for some cases of conformance tests between
4067 -- operators, where the declaration tree simply does not exist!
4069 Old_Formal := First_Formal (Old_Id);
4070 New_Formal := First_Formal (New_Id);
4071 while Present (Old_Formal) and then Present (New_Formal) loop
4072 if Is_Controlling_Formal (Old_Formal)
4073 and then Is_Controlling_Formal (New_Formal)
4074 and then Skip_Controlling_Formals
4076 -- The controlling formals will have different types when
4077 -- comparing an interface operation with its match, but both
4078 -- or neither must be access parameters.
4080 if Is_Access_Type (Etype (Old_Formal))
4082 Is_Access_Type (Etype (New_Formal))
4084 goto Skip_Controlling_Formal;
4087 ("\access parameter does not match!", New_Formal);
4091 if Ctype = Fully_Conformant then
4093 -- Names must match. Error message is more accurate if we do
4094 -- this before checking that the types of the formals match.
4096 if Chars (Old_Formal) /= Chars (New_Formal) then
4097 Conformance_Error ("\name & does not match!", New_Formal);
4099 -- Set error posted flag on new formal as well to stop
4100 -- junk cascaded messages in some cases.
4102 Set_Error_Posted (New_Formal);
4106 -- Null exclusion must match
4108 if Null_Exclusion_Present (Parent (Old_Formal))
4110 Null_Exclusion_Present (Parent (New_Formal))
4112 -- Only give error if both come from source. This should be
4113 -- investigated some time, since it should not be needed ???
4115 if Comes_From_Source (Old_Formal)
4117 Comes_From_Source (New_Formal)
4120 ("\null exclusion for & does not match", New_Formal);
4122 -- Mark error posted on the new formal to avoid duplicated
4123 -- complaint about types not matching.
4125 Set_Error_Posted (New_Formal);
4130 -- Ada 2005 (AI-423): Possible access [sub]type and itype match. This
4131 -- case occurs whenever a subprogram is being renamed and one of its
4132 -- parameters imposes a null exclusion. For example:
4134 -- type T is null record;
4135 -- type Acc_T is access T;
4136 -- subtype Acc_T_Sub is Acc_T;
4138 -- procedure P (Obj : not null Acc_T_Sub); -- itype
4139 -- procedure Ren_P (Obj : Acc_T_Sub) -- subtype
4142 Old_Formal_Base := Etype (Old_Formal);
4143 New_Formal_Base := Etype (New_Formal);
4146 Old_Formal_Base := Get_Instance_Of (Old_Formal_Base);
4147 New_Formal_Base := Get_Instance_Of (New_Formal_Base);
4150 Access_Types_Match := Ada_Version >= Ada_2005
4152 -- Ensure that this rule is only applied when New_Id is a
4153 -- renaming of Old_Id.
4155 and then Nkind (Parent (Parent (New_Id))) =
4156 N_Subprogram_Renaming_Declaration
4157 and then Nkind (Name (Parent (Parent (New_Id)))) in N_Has_Entity
4158 and then Present (Entity (Name (Parent (Parent (New_Id)))))
4159 and then Entity (Name (Parent (Parent (New_Id)))) = Old_Id
4161 -- Now handle the allowed access-type case
4163 and then Is_Access_Type (Old_Formal_Base)
4164 and then Is_Access_Type (New_Formal_Base)
4166 -- The type kinds must match. The only exception occurs with
4167 -- multiple generics of the form:
4170 -- type F is private; type A is private;
4171 -- type F_Ptr is access F; type A_Ptr is access A;
4172 -- with proc F_P (X : F_Ptr); with proc A_P (X : A_Ptr);
4173 -- package F_Pack is ... package A_Pack is
4174 -- package F_Inst is
4175 -- new F_Pack (A, A_Ptr, A_P);
4177 -- When checking for conformance between the parameters of A_P
4178 -- and F_P, the type kinds of F_Ptr and A_Ptr will not match
4179 -- because the compiler has transformed A_Ptr into a subtype of
4180 -- F_Ptr. We catch this case in the code below.
4182 and then (Ekind (Old_Formal_Base) = Ekind (New_Formal_Base)
4184 (Is_Generic_Type (Old_Formal_Base)
4185 and then Is_Generic_Type (New_Formal_Base)
4186 and then Is_Internal (New_Formal_Base)
4187 and then Etype (Etype (New_Formal_Base)) =
4189 and then Directly_Designated_Type (Old_Formal_Base) =
4190 Directly_Designated_Type (New_Formal_Base)
4191 and then ((Is_Itype (Old_Formal_Base)
4192 and then Can_Never_Be_Null (Old_Formal_Base))
4194 (Is_Itype (New_Formal_Base)
4195 and then Can_Never_Be_Null (New_Formal_Base)));
4197 -- Types must always match. In the visible part of an instance,
4198 -- usual overloading rules for dispatching operations apply, and
4199 -- we check base types (not the actual subtypes).
4201 if In_Instance_Visible_Part
4202 and then Is_Dispatching_Operation (New_Id)
4204 if not Conforming_Types
4205 (T1 => Base_Type (Etype (Old_Formal)),
4206 T2 => Base_Type (Etype (New_Formal)),
4208 Get_Inst => Get_Inst)
4209 and then not Access_Types_Match
4211 Conformance_Error ("\type of & does not match!", New_Formal);
4215 elsif not Conforming_Types
4216 (T1 => Old_Formal_Base,
4217 T2 => New_Formal_Base,
4219 Get_Inst => Get_Inst)
4220 and then not Access_Types_Match
4222 -- Don't give error message if old type is Any_Type. This test
4223 -- avoids some cascaded errors, e.g. in case of a bad spec.
4225 if Errmsg and then Old_Formal_Base = Any_Type then
4228 Conformance_Error ("\type of & does not match!", New_Formal);
4234 -- For mode conformance, mode must match
4236 if Ctype >= Mode_Conformant then
4237 if Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) then
4238 if not Ekind_In (New_Id, E_Function, E_Procedure)
4239 or else not Is_Primitive_Wrapper (New_Id)
4241 Conformance_Error ("\mode of & does not match!", New_Formal);
4245 T : constant Entity_Id := Find_Dispatching_Type (New_Id);
4247 if Is_Protected_Type
4248 (Corresponding_Concurrent_Type (T))
4250 Error_Msg_PT (T, New_Id);
4253 ("\mode of & does not match!", New_Formal);
4260 -- Part of mode conformance for access types is having the same
4261 -- constant modifier.
4263 elsif Access_Types_Match
4264 and then Is_Access_Constant (Old_Formal_Base) /=
4265 Is_Access_Constant (New_Formal_Base)
4268 ("\constant modifier does not match!", New_Formal);
4273 if Ctype >= Subtype_Conformant then
4275 -- Ada 2005 (AI-231): In case of anonymous access types check
4276 -- the null-exclusion and access-to-constant attributes must
4277 -- match. For null exclusion, we test the types rather than the
4278 -- formals themselves, since the attribute is only set reliably
4279 -- on the formals in the Ada 95 case, and we exclude the case
4280 -- where Old_Formal is marked as controlling, to avoid errors
4281 -- when matching completing bodies with dispatching declarations
4282 -- (access formals in the bodies aren't marked Can_Never_Be_Null).
4284 if Ada_Version >= Ada_2005
4285 and then Ekind (Etype (Old_Formal)) = E_Anonymous_Access_Type
4286 and then Ekind (Etype (New_Formal)) = E_Anonymous_Access_Type
4288 ((Can_Never_Be_Null (Etype (Old_Formal)) /=
4289 Can_Never_Be_Null (Etype (New_Formal))
4291 not Is_Controlling_Formal (Old_Formal))
4293 Is_Access_Constant (Etype (Old_Formal)) /=
4294 Is_Access_Constant (Etype (New_Formal)))
4296 -- Do not complain if error already posted on New_Formal. This
4297 -- avoids some redundant error messages.
4299 and then not Error_Posted (New_Formal)
4301 -- It is allowed to omit the null-exclusion in case of stream
4302 -- attribute subprograms. We recognize stream subprograms
4303 -- through their TSS-generated suffix.
4306 TSS_Name : constant TSS_Name_Type := Get_TSS_Name (New_Id);
4308 if TSS_Name /= TSS_Stream_Read
4309 and then TSS_Name /= TSS_Stream_Write
4310 and then TSS_Name /= TSS_Stream_Input
4311 and then TSS_Name /= TSS_Stream_Output
4314 ("\type of & does not match!", New_Formal);
4321 -- Full conformance checks
4323 if Ctype = Fully_Conformant then
4325 -- We have checked already that names match
4327 if Parameter_Mode (Old_Formal) = E_In_Parameter then
4329 -- Check default expressions for in parameters
4332 NewD : constant Boolean :=
4333 Present (Default_Value (New_Formal));
4334 OldD : constant Boolean :=
4335 Present (Default_Value (Old_Formal));
4337 if NewD or OldD then
4339 -- The old default value has been analyzed because the
4340 -- current full declaration will have frozen everything
4341 -- before. The new default value has not been analyzed,
4342 -- so analyze it now before we check for conformance.
4345 Push_Scope (New_Id);
4346 Preanalyze_Spec_Expression
4347 (Default_Value (New_Formal), Etype (New_Formal));
4351 if not (NewD and OldD)
4352 or else not Fully_Conformant_Expressions
4353 (Default_Value (Old_Formal),
4354 Default_Value (New_Formal))
4357 ("\default expression for & does not match!",
4366 -- A couple of special checks for Ada 83 mode. These checks are
4367 -- skipped if either entity is an operator in package Standard,
4368 -- or if either old or new instance is not from the source program.
4370 if Ada_Version = Ada_83
4371 and then Sloc (Old_Id) > Standard_Location
4372 and then Sloc (New_Id) > Standard_Location
4373 and then Comes_From_Source (Old_Id)
4374 and then Comes_From_Source (New_Id)
4377 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
4378 New_Param : constant Node_Id := Declaration_Node (New_Formal);
4381 -- Explicit IN must be present or absent in both cases. This
4382 -- test is required only in the full conformance case.
4384 if In_Present (Old_Param) /= In_Present (New_Param)
4385 and then Ctype = Fully_Conformant
4388 ("\(Ada 83) IN must appear in both declarations",
4393 -- Grouping (use of comma in param lists) must be the same
4394 -- This is where we catch a misconformance like:
4397 -- A : Integer; B : Integer
4399 -- which are represented identically in the tree except
4400 -- for the setting of the flags More_Ids and Prev_Ids.
4402 if More_Ids (Old_Param) /= More_Ids (New_Param)
4403 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
4406 ("\grouping of & does not match!", New_Formal);
4412 -- This label is required when skipping controlling formals
4414 <<Skip_Controlling_Formal>>
4416 Next_Formal (Old_Formal);
4417 Next_Formal (New_Formal);
4420 if Present (Old_Formal) then
4421 Conformance_Error ("\too few parameters!");
4424 elsif Present (New_Formal) then
4425 Conformance_Error ("\too many parameters!", New_Formal);
4428 end Check_Conformance;
4430 -----------------------
4431 -- Check_Conventions --
4432 -----------------------
4434 procedure Check_Conventions (Typ : Entity_Id) is
4435 Ifaces_List : Elist_Id;
4437 procedure Check_Convention (Op : Entity_Id);
4438 -- Verify that the convention of inherited dispatching operation Op is
4439 -- consistent among all subprograms it overrides. In order to minimize
4440 -- the search, Search_From is utilized to designate a specific point in
4441 -- the list rather than iterating over the whole list once more.
4443 ----------------------
4444 -- Check_Convention --
4445 ----------------------
4447 procedure Check_Convention (Op : Entity_Id) is
4448 Iface_Elmt : Elmt_Id;
4449 Iface_Prim_Elmt : Elmt_Id;
4450 Iface_Prim : Entity_Id;
4453 Iface_Elmt := First_Elmt (Ifaces_List);
4454 while Present (Iface_Elmt) loop
4456 First_Elmt (Primitive_Operations (Node (Iface_Elmt)));
4457 while Present (Iface_Prim_Elmt) loop
4458 Iface_Prim := Node (Iface_Prim_Elmt);
4460 if Is_Interface_Conformant (Typ, Iface_Prim, Op)
4461 and then Convention (Iface_Prim) /= Convention (Op)
4464 ("inconsistent conventions in primitive operations", Typ);
4466 Error_Msg_Name_1 := Chars (Op);
4467 Error_Msg_Name_2 := Get_Convention_Name (Convention (Op));
4468 Error_Msg_Sloc := Sloc (Op);
4470 if Comes_From_Source (Op) or else No (Alias (Op)) then
4471 if not Present (Overridden_Operation (Op)) then
4472 Error_Msg_N ("\\primitive % defined #", Typ);
4475 ("\\overriding operation % with " &
4476 "convention % defined #", Typ);
4479 else pragma Assert (Present (Alias (Op)));
4480 Error_Msg_Sloc := Sloc (Alias (Op));
4482 ("\\inherited operation % with " &
4483 "convention % defined #", Typ);
4486 Error_Msg_Name_1 := Chars (Op);
4488 Get_Convention_Name (Convention (Iface_Prim));
4489 Error_Msg_Sloc := Sloc (Iface_Prim);
4491 ("\\overridden operation % with " &
4492 "convention % defined #", Typ);
4494 -- Avoid cascading errors
4499 Next_Elmt (Iface_Prim_Elmt);
4502 Next_Elmt (Iface_Elmt);
4504 end Check_Convention;
4508 Prim_Op : Entity_Id;
4509 Prim_Op_Elmt : Elmt_Id;
4511 -- Start of processing for Check_Conventions
4514 if not Has_Interfaces (Typ) then
4518 Collect_Interfaces (Typ, Ifaces_List);
4520 -- The algorithm checks every overriding dispatching operation against
4521 -- all the corresponding overridden dispatching operations, detecting
4522 -- differences in conventions.
4524 Prim_Op_Elmt := First_Elmt (Primitive_Operations (Typ));
4525 while Present (Prim_Op_Elmt) loop
4526 Prim_Op := Node (Prim_Op_Elmt);
4528 -- A small optimization: skip the predefined dispatching operations
4529 -- since they always have the same convention.
4531 if not Is_Predefined_Dispatching_Operation (Prim_Op) then
4532 Check_Convention (Prim_Op);
4535 Next_Elmt (Prim_Op_Elmt);
4537 end Check_Conventions;
4539 ------------------------------
4540 -- Check_Delayed_Subprogram --
4541 ------------------------------
4543 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
4546 procedure Possible_Freeze (T : Entity_Id);
4547 -- T is the type of either a formal parameter or of the return type.
4548 -- If T is not yet frozen and needs a delayed freeze, then the
4549 -- subprogram itself must be delayed. If T is the limited view of an
4550 -- incomplete type the subprogram must be frozen as well, because
4551 -- T may depend on local types that have not been frozen yet.
4553 ---------------------
4554 -- Possible_Freeze --
4555 ---------------------
4557 procedure Possible_Freeze (T : Entity_Id) is
4559 if Has_Delayed_Freeze (T) and then not Is_Frozen (T) then
4560 Set_Has_Delayed_Freeze (Designator);
4562 elsif Is_Access_Type (T)
4563 and then Has_Delayed_Freeze (Designated_Type (T))
4564 and then not Is_Frozen (Designated_Type (T))
4566 Set_Has_Delayed_Freeze (Designator);
4568 elsif Ekind (T) = E_Incomplete_Type and then From_With_Type (T) then
4569 Set_Has_Delayed_Freeze (Designator);
4571 -- AI05-0151: In Ada 2012, Incomplete types can appear in the profile
4572 -- of a subprogram or entry declaration.
4574 elsif Ekind (T) = E_Incomplete_Type
4575 and then Ada_Version >= Ada_2012
4577 Set_Has_Delayed_Freeze (Designator);
4580 end Possible_Freeze;
4582 -- Start of processing for Check_Delayed_Subprogram
4585 -- All subprograms, including abstract subprograms, may need a freeze
4586 -- node if some formal type or the return type needs one.
4588 Possible_Freeze (Etype (Designator));
4589 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
4591 -- Need delayed freeze if any of the formal types themselves need
4592 -- a delayed freeze and are not yet frozen.
4594 F := First_Formal (Designator);
4595 while Present (F) loop
4596 Possible_Freeze (Etype (F));
4597 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
4601 -- Mark functions that return by reference. Note that it cannot be
4602 -- done for delayed_freeze subprograms because the underlying
4603 -- returned type may not be known yet (for private types)
4605 if not Has_Delayed_Freeze (Designator)
4606 and then Expander_Active
4609 Typ : constant Entity_Id := Etype (Designator);
4610 Utyp : constant Entity_Id := Underlying_Type (Typ);
4613 if Is_Immutably_Limited_Type (Typ) then
4614 Set_Returns_By_Ref (Designator);
4616 elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
4617 Set_Returns_By_Ref (Designator);
4621 end Check_Delayed_Subprogram;
4623 ------------------------------------
4624 -- Check_Discriminant_Conformance --
4625 ------------------------------------
4627 procedure Check_Discriminant_Conformance
4632 Old_Discr : Entity_Id := First_Discriminant (Prev);
4633 New_Discr : Node_Id := First (Discriminant_Specifications (N));
4634 New_Discr_Id : Entity_Id;
4635 New_Discr_Type : Entity_Id;
4637 procedure Conformance_Error (Msg : String; N : Node_Id);
4638 -- Post error message for conformance error on given node. Two messages
4639 -- are output. The first points to the previous declaration with a
4640 -- general "no conformance" message. The second is the detailed reason,
4641 -- supplied as Msg. The parameter N provide information for a possible
4642 -- & insertion in the message.
4644 -----------------------
4645 -- Conformance_Error --
4646 -----------------------
4648 procedure Conformance_Error (Msg : String; N : Node_Id) is
4650 Error_Msg_Sloc := Sloc (Prev_Loc);
4651 Error_Msg_N -- CODEFIX
4652 ("not fully conformant with declaration#!", N);
4653 Error_Msg_NE (Msg, N, N);
4654 end Conformance_Error;
4656 -- Start of processing for Check_Discriminant_Conformance
4659 while Present (Old_Discr) and then Present (New_Discr) loop
4661 New_Discr_Id := Defining_Identifier (New_Discr);
4663 -- The subtype mark of the discriminant on the full type has not
4664 -- been analyzed so we do it here. For an access discriminant a new
4667 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
4669 Access_Definition (N, Discriminant_Type (New_Discr));
4672 Analyze (Discriminant_Type (New_Discr));
4673 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
4675 -- Ada 2005: if the discriminant definition carries a null
4676 -- exclusion, create an itype to check properly for consistency
4677 -- with partial declaration.
4679 if Is_Access_Type (New_Discr_Type)
4680 and then Null_Exclusion_Present (New_Discr)
4683 Create_Null_Excluding_Itype
4684 (T => New_Discr_Type,
4685 Related_Nod => New_Discr,
4686 Scope_Id => Current_Scope);
4690 if not Conforming_Types
4691 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
4693 Conformance_Error ("type of & does not match!", New_Discr_Id);
4696 -- Treat the new discriminant as an occurrence of the old one,
4697 -- for navigation purposes, and fill in some semantic
4698 -- information, for completeness.
4700 Generate_Reference (Old_Discr, New_Discr_Id, 'r');
4701 Set_Etype (New_Discr_Id, Etype (Old_Discr));
4702 Set_Scope (New_Discr_Id, Scope (Old_Discr));
4707 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
4708 Conformance_Error ("name & does not match!", New_Discr_Id);
4712 -- Default expressions must match
4715 NewD : constant Boolean :=
4716 Present (Expression (New_Discr));
4717 OldD : constant Boolean :=
4718 Present (Expression (Parent (Old_Discr)));
4721 if NewD or OldD then
4723 -- The old default value has been analyzed and expanded,
4724 -- because the current full declaration will have frozen
4725 -- everything before. The new default values have not been
4726 -- expanded, so expand now to check conformance.
4729 Preanalyze_Spec_Expression
4730 (Expression (New_Discr), New_Discr_Type);
4733 if not (NewD and OldD)
4734 or else not Fully_Conformant_Expressions
4735 (Expression (Parent (Old_Discr)),
4736 Expression (New_Discr))
4740 ("default expression for & does not match!",
4747 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
4749 if Ada_Version = Ada_83 then
4751 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
4754 -- Grouping (use of comma in param lists) must be the same
4755 -- This is where we catch a misconformance like:
4758 -- A : Integer; B : Integer
4760 -- which are represented identically in the tree except
4761 -- for the setting of the flags More_Ids and Prev_Ids.
4763 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
4764 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
4767 ("grouping of & does not match!", New_Discr_Id);
4773 Next_Discriminant (Old_Discr);
4777 if Present (Old_Discr) then
4778 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
4781 elsif Present (New_Discr) then
4783 ("too many discriminants!", Defining_Identifier (New_Discr));
4786 end Check_Discriminant_Conformance;
4788 ----------------------------
4789 -- Check_Fully_Conformant --
4790 ----------------------------
4792 procedure Check_Fully_Conformant
4793 (New_Id : Entity_Id;
4795 Err_Loc : Node_Id := Empty)
4798 pragma Warnings (Off, Result);
4801 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
4802 end Check_Fully_Conformant;
4804 ---------------------------
4805 -- Check_Mode_Conformant --
4806 ---------------------------
4808 procedure Check_Mode_Conformant
4809 (New_Id : Entity_Id;
4811 Err_Loc : Node_Id := Empty;
4812 Get_Inst : Boolean := False)
4815 pragma Warnings (Off, Result);
4818 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
4819 end Check_Mode_Conformant;
4821 --------------------------------
4822 -- Check_Overriding_Indicator --
4823 --------------------------------
4825 procedure Check_Overriding_Indicator
4827 Overridden_Subp : Entity_Id;
4828 Is_Primitive : Boolean)
4834 -- No overriding indicator for literals
4836 if Ekind (Subp) = E_Enumeration_Literal then
4839 elsif Ekind (Subp) = E_Entry then
4840 Decl := Parent (Subp);
4842 -- No point in analyzing a malformed operator
4844 elsif Nkind (Subp) = N_Defining_Operator_Symbol
4845 and then Error_Posted (Subp)
4850 Decl := Unit_Declaration_Node (Subp);
4853 if Nkind_In (Decl, N_Subprogram_Body,
4854 N_Subprogram_Body_Stub,
4855 N_Subprogram_Declaration,
4856 N_Abstract_Subprogram_Declaration,
4857 N_Subprogram_Renaming_Declaration)
4859 Spec := Specification (Decl);
4861 elsif Nkind (Decl) = N_Entry_Declaration then
4868 -- The overriding operation is type conformant with the overridden one,
4869 -- but the names of the formals are not required to match. If the names
4870 -- appear permuted in the overriding operation, this is a possible
4871 -- source of confusion that is worth diagnosing. Controlling formals
4872 -- often carry names that reflect the type, and it is not worthwhile
4873 -- requiring that their names match.
4875 if Present (Overridden_Subp)
4876 and then Nkind (Subp) /= N_Defining_Operator_Symbol
4883 Form1 := First_Formal (Subp);
4884 Form2 := First_Formal (Overridden_Subp);
4886 -- If the overriding operation is a synchronized operation, skip
4887 -- the first parameter of the overridden operation, which is
4888 -- implicit in the new one. If the operation is declared in the
4889 -- body it is not primitive and all formals must match.
4891 if Is_Concurrent_Type (Scope (Subp))
4892 and then Is_Tagged_Type (Scope (Subp))
4893 and then not Has_Completion (Scope (Subp))
4895 Form2 := Next_Formal (Form2);
4898 if Present (Form1) then
4899 Form1 := Next_Formal (Form1);
4900 Form2 := Next_Formal (Form2);
4903 while Present (Form1) loop
4904 if not Is_Controlling_Formal (Form1)
4905 and then Present (Next_Formal (Form2))
4906 and then Chars (Form1) = Chars (Next_Formal (Form2))
4908 Error_Msg_Node_2 := Alias (Overridden_Subp);
4909 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
4911 ("& does not match corresponding formal of&#",
4916 Next_Formal (Form1);
4917 Next_Formal (Form2);
4922 -- If there is an overridden subprogram, then check that there is no
4923 -- "not overriding" indicator, and mark the subprogram as overriding.
4924 -- This is not done if the overridden subprogram is marked as hidden,
4925 -- which can occur for the case of inherited controlled operations
4926 -- (see Derive_Subprogram), unless the inherited subprogram's parent
4927 -- subprogram is not itself hidden. (Note: This condition could probably
4928 -- be simplified, leaving out the testing for the specific controlled
4929 -- cases, but it seems safer and clearer this way, and echoes similar
4930 -- special-case tests of this kind in other places.)
4932 if Present (Overridden_Subp)
4933 and then (not Is_Hidden (Overridden_Subp)
4935 ((Chars (Overridden_Subp) = Name_Initialize
4937 Chars (Overridden_Subp) = Name_Adjust
4939 Chars (Overridden_Subp) = Name_Finalize)
4940 and then Present (Alias (Overridden_Subp))
4941 and then not Is_Hidden (Alias (Overridden_Subp))))
4943 if Must_Not_Override (Spec) then
4944 Error_Msg_Sloc := Sloc (Overridden_Subp);
4946 if Ekind (Subp) = E_Entry then
4948 ("entry & overrides inherited operation #", Spec, Subp);
4951 ("subprogram & overrides inherited operation #", Spec, Subp);
4954 elsif Is_Subprogram (Subp) then
4955 if Is_Init_Proc (Subp) then
4958 elsif No (Overridden_Operation (Subp)) then
4960 -- For entities generated by Derive_Subprograms the overridden
4961 -- operation is the inherited primitive (which is available
4962 -- through the attribute alias)
4964 if (Is_Dispatching_Operation (Subp)
4965 or else Is_Dispatching_Operation (Overridden_Subp))
4966 and then not Comes_From_Source (Overridden_Subp)
4967 and then Find_Dispatching_Type (Overridden_Subp) =
4968 Find_Dispatching_Type (Subp)
4969 and then Present (Alias (Overridden_Subp))
4970 and then Comes_From_Source (Alias (Overridden_Subp))
4972 Set_Overridden_Operation (Subp, Alias (Overridden_Subp));
4975 Set_Overridden_Operation (Subp, Overridden_Subp);
4980 -- If primitive flag is set or this is a protected operation, then
4981 -- the operation is overriding at the point of its declaration, so
4982 -- warn if necessary. Otherwise it may have been declared before the
4983 -- operation it overrides and no check is required.
4986 and then not Must_Override (Spec)
4987 and then (Is_Primitive
4988 or else Ekind (Scope (Subp)) = E_Protected_Type)
4990 Style.Missing_Overriding (Decl, Subp);
4993 -- If Subp is an operator, it may override a predefined operation, if
4994 -- it is defined in the same scope as the type to which it applies.
4995 -- In that case Overridden_Subp is empty because of our implicit
4996 -- representation for predefined operators. We have to check whether the
4997 -- signature of Subp matches that of a predefined operator. Note that
4998 -- first argument provides the name of the operator, and the second
4999 -- argument the signature that may match that of a standard operation.
5000 -- If the indicator is overriding, then the operator must match a
5001 -- predefined signature, because we know already that there is no
5002 -- explicit overridden operation.
5004 elsif Nkind (Subp) = N_Defining_Operator_Symbol then
5005 if Must_Not_Override (Spec) then
5007 -- If this is not a primitive or a protected subprogram, then
5008 -- "not overriding" is illegal.
5011 and then Ekind (Scope (Subp)) /= E_Protected_Type
5014 ("overriding indicator only allowed "
5015 & "if subprogram is primitive", Subp);
5017 elsif Can_Override_Operator (Subp) then
5019 ("subprogram& overrides predefined operator ", Spec, Subp);
5022 elsif Must_Override (Spec) then
5023 if No (Overridden_Operation (Subp))
5024 and then not Can_Override_Operator (Subp)
5026 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5029 elsif not Error_Posted (Subp)
5030 and then Style_Check
5031 and then Can_Override_Operator (Subp)
5033 not Is_Predefined_File_Name
5034 (Unit_File_Name (Get_Source_Unit (Subp)))
5036 -- If style checks are enabled, indicate that the indicator is
5037 -- missing. However, at the point of declaration, the type of
5038 -- which this is a primitive operation may be private, in which
5039 -- case the indicator would be premature.
5041 if Has_Private_Declaration (Etype (Subp))
5042 or else Has_Private_Declaration (Etype (First_Formal (Subp)))
5046 Style.Missing_Overriding (Decl, Subp);
5050 elsif Must_Override (Spec) then
5051 if Ekind (Subp) = E_Entry then
5052 Error_Msg_NE ("entry & is not overriding", Spec, Subp);
5054 Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
5057 -- If the operation is marked "not overriding" and it's not primitive
5058 -- then an error is issued, unless this is an operation of a task or
5059 -- protected type (RM05-8.3.1(3/2-4/2)). Error cases where "overriding"
5060 -- has been specified have already been checked above.
5062 elsif Must_Not_Override (Spec)
5063 and then not Is_Primitive
5064 and then Ekind (Subp) /= E_Entry
5065 and then Ekind (Scope (Subp)) /= E_Protected_Type
5068 ("overriding indicator only allowed if subprogram is primitive",
5072 end Check_Overriding_Indicator;
5078 -- Note: this procedure needs to know far too much about how the expander
5079 -- messes with exceptions. The use of the flag Exception_Junk and the
5080 -- incorporation of knowledge of Exp_Ch11.Expand_Local_Exception_Handlers
5081 -- works, but is not very clean. It would be better if the expansion
5082 -- routines would leave Original_Node working nicely, and we could use
5083 -- Original_Node here to ignore all the peculiar expander messing ???
5085 procedure Check_Returns
5089 Proc : Entity_Id := Empty)
5093 procedure Check_Statement_Sequence (L : List_Id);
5094 -- Internal recursive procedure to check a list of statements for proper
5095 -- termination by a return statement (or a transfer of control or a
5096 -- compound statement that is itself internally properly terminated).
5098 ------------------------------
5099 -- Check_Statement_Sequence --
5100 ------------------------------
5102 procedure Check_Statement_Sequence (L : List_Id) is
5107 Raise_Exception_Call : Boolean;
5108 -- Set True if statement sequence terminated by Raise_Exception call
5109 -- or a Reraise_Occurrence call.
5112 Raise_Exception_Call := False;
5114 -- Get last real statement
5116 Last_Stm := Last (L);
5118 -- Deal with digging out exception handler statement sequences that
5119 -- have been transformed by the local raise to goto optimization.
5120 -- See Exp_Ch11.Expand_Local_Exception_Handlers for details. If this
5121 -- optimization has occurred, we are looking at something like:
5124 -- original stmts in block
5128 -- goto L1; | omitted if No_Exception_Propagation
5133 -- goto L3; -- skip handler when exception not raised
5135 -- <<L1>> -- target label for local exception
5149 -- and what we have to do is to dig out the estmts1 and estmts2
5150 -- sequences (which were the original sequences of statements in
5151 -- the exception handlers) and check them.
5153 if Nkind (Last_Stm) = N_Label
5154 and then Exception_Junk (Last_Stm)
5160 exit when Nkind (Stm) /= N_Block_Statement;
5161 exit when not Exception_Junk (Stm);
5164 exit when Nkind (Stm) /= N_Label;
5165 exit when not Exception_Junk (Stm);
5166 Check_Statement_Sequence
5167 (Statements (Handled_Statement_Sequence (Next (Stm))));
5172 exit when Nkind (Stm) /= N_Goto_Statement;
5173 exit when not Exception_Junk (Stm);
5177 -- Don't count pragmas
5179 while Nkind (Last_Stm) = N_Pragma
5181 -- Don't count call to SS_Release (can happen after Raise_Exception)
5184 (Nkind (Last_Stm) = N_Procedure_Call_Statement
5186 Nkind (Name (Last_Stm)) = N_Identifier
5188 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
5190 -- Don't count exception junk
5193 (Nkind_In (Last_Stm, N_Goto_Statement,
5195 N_Object_Declaration)
5196 and then Exception_Junk (Last_Stm))
5197 or else Nkind (Last_Stm) in N_Push_xxx_Label
5198 or else Nkind (Last_Stm) in N_Pop_xxx_Label
5203 -- Here we have the "real" last statement
5205 Kind := Nkind (Last_Stm);
5207 -- Transfer of control, OK. Note that in the No_Return procedure
5208 -- case, we already diagnosed any explicit return statements, so
5209 -- we can treat them as OK in this context.
5211 if Is_Transfer (Last_Stm) then
5214 -- Check cases of explicit non-indirect procedure calls
5216 elsif Kind = N_Procedure_Call_Statement
5217 and then Is_Entity_Name (Name (Last_Stm))
5219 -- Check call to Raise_Exception procedure which is treated
5220 -- specially, as is a call to Reraise_Occurrence.
5222 -- We suppress the warning in these cases since it is likely that
5223 -- the programmer really does not expect to deal with the case
5224 -- of Null_Occurrence, and thus would find a warning about a
5225 -- missing return curious, and raising Program_Error does not
5226 -- seem such a bad behavior if this does occur.
5228 -- Note that in the Ada 2005 case for Raise_Exception, the actual
5229 -- behavior will be to raise Constraint_Error (see AI-329).
5231 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
5233 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
5235 Raise_Exception_Call := True;
5237 -- For Raise_Exception call, test first argument, if it is
5238 -- an attribute reference for a 'Identity call, then we know
5239 -- that the call cannot possibly return.
5242 Arg : constant Node_Id :=
5243 Original_Node (First_Actual (Last_Stm));
5245 if Nkind (Arg) = N_Attribute_Reference
5246 and then Attribute_Name (Arg) = Name_Identity
5253 -- If statement, need to look inside if there is an else and check
5254 -- each constituent statement sequence for proper termination.
5256 elsif Kind = N_If_Statement
5257 and then Present (Else_Statements (Last_Stm))
5259 Check_Statement_Sequence (Then_Statements (Last_Stm));
5260 Check_Statement_Sequence (Else_Statements (Last_Stm));
5262 if Present (Elsif_Parts (Last_Stm)) then
5264 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
5267 while Present (Elsif_Part) loop
5268 Check_Statement_Sequence (Then_Statements (Elsif_Part));
5276 -- Case statement, check each case for proper termination
5278 elsif Kind = N_Case_Statement then
5282 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
5283 while Present (Case_Alt) loop
5284 Check_Statement_Sequence (Statements (Case_Alt));
5285 Next_Non_Pragma (Case_Alt);
5291 -- Block statement, check its handled sequence of statements
5293 elsif Kind = N_Block_Statement then
5299 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
5308 -- Loop statement. If there is an iteration scheme, we can definitely
5309 -- fall out of the loop. Similarly if there is an exit statement, we
5310 -- can fall out. In either case we need a following return.
5312 elsif Kind = N_Loop_Statement then
5313 if Present (Iteration_Scheme (Last_Stm))
5314 or else Has_Exit (Entity (Identifier (Last_Stm)))
5318 -- A loop with no exit statement or iteration scheme is either
5319 -- an infinite loop, or it has some other exit (raise/return).
5320 -- In either case, no warning is required.
5326 -- Timed entry call, check entry call and delay alternatives
5328 -- Note: in expanded code, the timed entry call has been converted
5329 -- to a set of expanded statements on which the check will work
5330 -- correctly in any case.
5332 elsif Kind = N_Timed_Entry_Call then
5334 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5335 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
5338 -- If statement sequence of entry call alternative is missing,
5339 -- then we can definitely fall through, and we post the error
5340 -- message on the entry call alternative itself.
5342 if No (Statements (ECA)) then
5345 -- If statement sequence of delay alternative is missing, then
5346 -- we can definitely fall through, and we post the error
5347 -- message on the delay alternative itself.
5349 -- Note: if both ECA and DCA are missing the return, then we
5350 -- post only one message, should be enough to fix the bugs.
5351 -- If not we will get a message next time on the DCA when the
5354 elsif No (Statements (DCA)) then
5357 -- Else check both statement sequences
5360 Check_Statement_Sequence (Statements (ECA));
5361 Check_Statement_Sequence (Statements (DCA));
5366 -- Conditional entry call, check entry call and else part
5368 -- Note: in expanded code, the conditional entry call has been
5369 -- converted to a set of expanded statements on which the check
5370 -- will work correctly in any case.
5372 elsif Kind = N_Conditional_Entry_Call then
5374 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
5377 -- If statement sequence of entry call alternative is missing,
5378 -- then we can definitely fall through, and we post the error
5379 -- message on the entry call alternative itself.
5381 if No (Statements (ECA)) then
5384 -- Else check statement sequence and else part
5387 Check_Statement_Sequence (Statements (ECA));
5388 Check_Statement_Sequence (Else_Statements (Last_Stm));
5394 -- If we fall through, issue appropriate message
5397 if not Raise_Exception_Call then
5399 ("?RETURN statement missing following this statement!",
5402 ("\?Program_Error may be raised at run time!",
5406 -- Note: we set Err even though we have not issued a warning
5407 -- because we still have a case of a missing return. This is
5408 -- an extremely marginal case, probably will never be noticed
5409 -- but we might as well get it right.
5413 -- Otherwise we have the case of a procedure marked No_Return
5416 if not Raise_Exception_Call then
5418 ("?implied return after this statement " &
5419 "will raise Program_Error",
5422 ("\?procedure & is marked as No_Return!",
5427 RE : constant Node_Id :=
5428 Make_Raise_Program_Error (Sloc (Last_Stm),
5429 Reason => PE_Implicit_Return);
5431 Insert_After (Last_Stm, RE);
5435 end Check_Statement_Sequence;
5437 -- Start of processing for Check_Returns
5441 Check_Statement_Sequence (Statements (HSS));
5443 if Present (Exception_Handlers (HSS)) then
5444 Handler := First_Non_Pragma (Exception_Handlers (HSS));
5445 while Present (Handler) loop
5446 Check_Statement_Sequence (Statements (Handler));
5447 Next_Non_Pragma (Handler);
5452 ----------------------------
5453 -- Check_Subprogram_Order --
5454 ----------------------------
5456 procedure Check_Subprogram_Order (N : Node_Id) is
5458 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
5459 -- This is used to check if S1 > S2 in the sense required by this
5460 -- test, for example nameab < namec, but name2 < name10.
5462 -----------------------------
5463 -- Subprogram_Name_Greater --
5464 -----------------------------
5466 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
5471 -- Remove trailing numeric parts
5474 while S1 (L1) in '0' .. '9' loop
5479 while S2 (L2) in '0' .. '9' loop
5483 -- If non-numeric parts non-equal, that's decisive
5485 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
5488 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
5491 -- If non-numeric parts equal, compare suffixed numeric parts. Note
5492 -- that a missing suffix is treated as numeric zero in this test.
5496 while L1 < S1'Last loop
5498 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
5502 while L2 < S2'Last loop
5504 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
5509 end Subprogram_Name_Greater;
5511 -- Start of processing for Check_Subprogram_Order
5514 -- Check body in alpha order if this is option
5517 and then Style_Check_Order_Subprograms
5518 and then Nkind (N) = N_Subprogram_Body
5519 and then Comes_From_Source (N)
5520 and then In_Extended_Main_Source_Unit (N)
5524 renames Scope_Stack.Table
5525 (Scope_Stack.Last).Last_Subprogram_Name;
5527 Body_Id : constant Entity_Id :=
5528 Defining_Entity (Specification (N));
5531 Get_Decoded_Name_String (Chars (Body_Id));
5534 if Subprogram_Name_Greater
5535 (LSN.all, Name_Buffer (1 .. Name_Len))
5537 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
5543 LSN := new String'(Name_Buffer (1 .. Name_Len));
5546 end Check_Subprogram_Order;
5548 ------------------------------
5549 -- Check_Subtype_Conformant --
5550 ------------------------------
5552 procedure Check_Subtype_Conformant
5553 (New_Id : Entity_Id;
5555 Err_Loc : Node_Id := Empty;
5556 Skip_Controlling_Formals : Boolean := False)
5559 pragma Warnings (Off, Result);
5562 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc,
5563 Skip_Controlling_Formals => Skip_Controlling_Formals);
5564 end Check_Subtype_Conformant;
5566 ---------------------------
5567 -- Check_Type_Conformant --
5568 ---------------------------
5570 procedure Check_Type_Conformant
5571 (New_Id : Entity_Id;
5573 Err_Loc : Node_Id := Empty)
5576 pragma Warnings (Off, Result);
5579 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
5580 end Check_Type_Conformant;
5582 ---------------------------
5583 -- Can_Override_Operator --
5584 ---------------------------
5586 function Can_Override_Operator (Subp : Entity_Id) return Boolean is
5589 if Nkind (Subp) /= N_Defining_Operator_Symbol then
5593 Typ := Base_Type (Etype (First_Formal (Subp)));
5595 return Operator_Matches_Spec (Subp, Subp)
5596 and then Scope (Subp) = Scope (Typ)
5597 and then not Is_Class_Wide_Type (Typ);
5599 end Can_Override_Operator;
5601 ----------------------
5602 -- Conforming_Types --
5603 ----------------------
5605 function Conforming_Types
5608 Ctype : Conformance_Type;
5609 Get_Inst : Boolean := False) return Boolean
5611 Type_1 : Entity_Id := T1;
5612 Type_2 : Entity_Id := T2;
5613 Are_Anonymous_Access_To_Subprogram_Types : Boolean := False;
5615 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
5616 -- If neither T1 nor T2 are generic actual types, or if they are in
5617 -- different scopes (e.g. parent and child instances), then verify that
5618 -- the base types are equal. Otherwise T1 and T2 must be on the same
5619 -- subtype chain. The whole purpose of this procedure is to prevent
5620 -- spurious ambiguities in an instantiation that may arise if two
5621 -- distinct generic types are instantiated with the same actual.
5623 function Find_Designated_Type (T : Entity_Id) return Entity_Id;
5624 -- An access parameter can designate an incomplete type. If the
5625 -- incomplete type is the limited view of a type from a limited_
5626 -- with_clause, check whether the non-limited view is available. If
5627 -- it is a (non-limited) incomplete type, get the full view.
5629 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean;
5630 -- Returns True if and only if either T1 denotes a limited view of T2
5631 -- or T2 denotes a limited view of T1. This can arise when the limited
5632 -- with view of a type is used in a subprogram declaration and the
5633 -- subprogram body is in the scope of a regular with clause for the
5634 -- same unit. In such a case, the two type entities can be considered
5635 -- identical for purposes of conformance checking.
5637 ----------------------
5638 -- Base_Types_Match --
5639 ----------------------
5641 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
5646 elsif Base_Type (T1) = Base_Type (T2) then
5648 -- The following is too permissive. A more precise test should
5649 -- check that the generic actual is an ancestor subtype of the
5652 return not Is_Generic_Actual_Type (T1)
5653 or else not Is_Generic_Actual_Type (T2)
5654 or else Scope (T1) /= Scope (T2);
5659 end Base_Types_Match;
5661 --------------------------
5662 -- Find_Designated_Type --
5663 --------------------------
5665 function Find_Designated_Type (T : Entity_Id) return Entity_Id is
5669 Desig := Directly_Designated_Type (T);
5671 if Ekind (Desig) = E_Incomplete_Type then
5673 -- If regular incomplete type, get full view if available
5675 if Present (Full_View (Desig)) then
5676 Desig := Full_View (Desig);
5678 -- If limited view of a type, get non-limited view if available,
5679 -- and check again for a regular incomplete type.
5681 elsif Present (Non_Limited_View (Desig)) then
5682 Desig := Get_Full_View (Non_Limited_View (Desig));
5687 end Find_Designated_Type;
5689 -------------------------------
5690 -- Matches_Limited_With_View --
5691 -------------------------------
5693 function Matches_Limited_With_View (T1, T2 : Entity_Id) return Boolean is
5695 -- In some cases a type imported through a limited_with clause, and
5696 -- its nonlimited view are both visible, for example in an anonymous
5697 -- access-to-class-wide type in a formal. Both entities designate the
5700 if From_With_Type (T1)
5701 and then T2 = Available_View (T1)
5705 elsif From_With_Type (T2)
5706 and then T1 = Available_View (T2)
5710 elsif From_With_Type (T1)
5711 and then From_With_Type (T2)
5712 and then Available_View (T1) = Available_View (T2)
5719 end Matches_Limited_With_View;
5721 -- Start of processing for Conforming_Types
5724 -- The context is an instance association for a formal
5725 -- access-to-subprogram type; the formal parameter types require
5726 -- mapping because they may denote other formal parameters of the
5730 Type_1 := Get_Instance_Of (T1);
5731 Type_2 := Get_Instance_Of (T2);
5734 -- If one of the types is a view of the other introduced by a limited
5735 -- with clause, treat these as conforming for all purposes.
5737 if Matches_Limited_With_View (T1, T2) then
5740 elsif Base_Types_Match (Type_1, Type_2) then
5741 return Ctype <= Mode_Conformant
5742 or else Subtypes_Statically_Match (Type_1, Type_2);
5744 elsif Is_Incomplete_Or_Private_Type (Type_1)
5745 and then Present (Full_View (Type_1))
5746 and then Base_Types_Match (Full_View (Type_1), Type_2)
5748 return Ctype <= Mode_Conformant
5749 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
5751 elsif Ekind (Type_2) = E_Incomplete_Type
5752 and then Present (Full_View (Type_2))
5753 and then Base_Types_Match (Type_1, Full_View (Type_2))
5755 return Ctype <= Mode_Conformant
5756 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5758 elsif Is_Private_Type (Type_2)
5759 and then In_Instance
5760 and then Present (Full_View (Type_2))
5761 and then Base_Types_Match (Type_1, Full_View (Type_2))
5763 return Ctype <= Mode_Conformant
5764 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
5767 -- Ada 2005 (AI-254): Anonymous access-to-subprogram types must be
5768 -- treated recursively because they carry a signature.
5770 Are_Anonymous_Access_To_Subprogram_Types :=
5771 Ekind (Type_1) = Ekind (Type_2)
5773 (Ekind (Type_1) = E_Anonymous_Access_Subprogram_Type
5775 Ekind (Type_1) = E_Anonymous_Access_Protected_Subprogram_Type);
5777 -- Test anonymous access type case. For this case, static subtype
5778 -- matching is required for mode conformance (RM 6.3.1(15)). We check
5779 -- the base types because we may have built internal subtype entities
5780 -- to handle null-excluding types (see Process_Formals).
5782 if (Ekind (Base_Type (Type_1)) = E_Anonymous_Access_Type
5784 Ekind (Base_Type (Type_2)) = E_Anonymous_Access_Type)
5785 or else Are_Anonymous_Access_To_Subprogram_Types -- Ada 2005 (AI-254)
5788 Desig_1 : Entity_Id;
5789 Desig_2 : Entity_Id;
5792 -- In Ada2005, access constant indicators must match for
5793 -- subtype conformance.
5795 if Ada_Version >= Ada_2005
5796 and then Ctype >= Subtype_Conformant
5798 Is_Access_Constant (Type_1) /= Is_Access_Constant (Type_2)
5803 Desig_1 := Find_Designated_Type (Type_1);
5804 Desig_2 := Find_Designated_Type (Type_2);
5806 -- If the context is an instance association for a formal
5807 -- access-to-subprogram type; formal access parameter designated
5808 -- types require mapping because they may denote other formal
5809 -- parameters of the generic unit.
5812 Desig_1 := Get_Instance_Of (Desig_1);
5813 Desig_2 := Get_Instance_Of (Desig_2);
5816 -- It is possible for a Class_Wide_Type to be introduced for an
5817 -- incomplete type, in which case there is a separate class_ wide
5818 -- type for the full view. The types conform if their Etypes
5819 -- conform, i.e. one may be the full view of the other. This can
5820 -- only happen in the context of an access parameter, other uses
5821 -- of an incomplete Class_Wide_Type are illegal.
5823 if Is_Class_Wide_Type (Desig_1)
5825 Is_Class_Wide_Type (Desig_2)
5829 (Etype (Base_Type (Desig_1)),
5830 Etype (Base_Type (Desig_2)), Ctype);
5832 elsif Are_Anonymous_Access_To_Subprogram_Types then
5833 if Ada_Version < Ada_2005 then
5834 return Ctype = Type_Conformant
5836 Subtypes_Statically_Match (Desig_1, Desig_2);
5838 -- We must check the conformance of the signatures themselves
5842 Conformant : Boolean;
5845 (Desig_1, Desig_2, Ctype, False, Conformant);
5851 return Base_Type (Desig_1) = Base_Type (Desig_2)
5852 and then (Ctype = Type_Conformant
5854 Subtypes_Statically_Match (Desig_1, Desig_2));
5858 -- Otherwise definitely no match
5861 if ((Ekind (Type_1) = E_Anonymous_Access_Type
5862 and then Is_Access_Type (Type_2))
5863 or else (Ekind (Type_2) = E_Anonymous_Access_Type
5864 and then Is_Access_Type (Type_1)))
5867 (Designated_Type (Type_1), Designated_Type (Type_2), Ctype)
5869 May_Hide_Profile := True;
5874 end Conforming_Types;
5876 --------------------------
5877 -- Create_Extra_Formals --
5878 --------------------------
5880 procedure Create_Extra_Formals (E : Entity_Id) is
5882 First_Extra : Entity_Id := Empty;
5883 Last_Extra : Entity_Id;
5884 Formal_Type : Entity_Id;
5885 P_Formal : Entity_Id := Empty;
5887 function Add_Extra_Formal
5888 (Assoc_Entity : Entity_Id;
5891 Suffix : String) return Entity_Id;
5892 -- Add an extra formal to the current list of formals and extra formals.
5893 -- The extra formal is added to the end of the list of extra formals,
5894 -- and also returned as the result. These formals are always of mode IN.
5895 -- The new formal has the type Typ, is declared in Scope, and its name
5896 -- is given by a concatenation of the name of Assoc_Entity and Suffix.
5897 -- The following suffixes are currently used. They should not be changed
5898 -- without coordinating with CodePeer, which makes use of these to
5899 -- provide better messages.
5901 -- O denotes the Constrained bit.
5902 -- L denotes the accessibility level.
5903 -- BIP_xxx denotes an extra formal for a build-in-place function. See
5904 -- the full list in exp_ch6.BIP_Formal_Kind.
5906 ----------------------
5907 -- Add_Extra_Formal --
5908 ----------------------
5910 function Add_Extra_Formal
5911 (Assoc_Entity : Entity_Id;
5914 Suffix : String) return Entity_Id
5916 EF : constant Entity_Id :=
5917 Make_Defining_Identifier (Sloc (Assoc_Entity),
5918 Chars => New_External_Name (Chars (Assoc_Entity),
5922 -- A little optimization. Never generate an extra formal for the
5923 -- _init operand of an initialization procedure, since it could
5926 if Chars (Formal) = Name_uInit then
5930 Set_Ekind (EF, E_In_Parameter);
5931 Set_Actual_Subtype (EF, Typ);
5932 Set_Etype (EF, Typ);
5933 Set_Scope (EF, Scope);
5934 Set_Mechanism (EF, Default_Mechanism);
5935 Set_Formal_Validity (EF);
5937 if No (First_Extra) then
5939 Set_Extra_Formals (Scope, First_Extra);
5942 if Present (Last_Extra) then
5943 Set_Extra_Formal (Last_Extra, EF);
5949 end Add_Extra_Formal;
5951 -- Start of processing for Create_Extra_Formals
5954 -- We never generate extra formals if expansion is not active
5955 -- because we don't need them unless we are generating code.
5957 if not Expander_Active then
5961 -- If this is a derived subprogram then the subtypes of the parent
5962 -- subprogram's formal parameters will be used to determine the need
5963 -- for extra formals.
5965 if Is_Overloadable (E) and then Present (Alias (E)) then
5966 P_Formal := First_Formal (Alias (E));
5969 Last_Extra := Empty;
5970 Formal := First_Formal (E);
5971 while Present (Formal) loop
5972 Last_Extra := Formal;
5973 Next_Formal (Formal);
5976 -- If Extra_formals were already created, don't do it again. This
5977 -- situation may arise for subprogram types created as part of
5978 -- dispatching calls (see Expand_Dispatching_Call)
5980 if Present (Last_Extra) and then
5981 Present (Extra_Formal (Last_Extra))
5986 -- If the subprogram is a predefined dispatching subprogram then don't
5987 -- generate any extra constrained or accessibility level formals. In
5988 -- general we suppress these for internal subprograms (by not calling
5989 -- Freeze_Subprogram and Create_Extra_Formals at all), but internally
5990 -- generated stream attributes do get passed through because extra
5991 -- build-in-place formals are needed in some cases (limited 'Input).
5993 if Is_Predefined_Internal_Operation (E) then
5994 goto Test_For_BIP_Extras;
5997 Formal := First_Formal (E);
5998 while Present (Formal) loop
6000 -- Create extra formal for supporting the attribute 'Constrained.
6001 -- The case of a private type view without discriminants also
6002 -- requires the extra formal if the underlying type has defaulted
6005 if Ekind (Formal) /= E_In_Parameter then
6006 if Present (P_Formal) then
6007 Formal_Type := Etype (P_Formal);
6009 Formal_Type := Etype (Formal);
6012 -- Do not produce extra formals for Unchecked_Union parameters.
6013 -- Jump directly to the end of the loop.
6015 if Is_Unchecked_Union (Base_Type (Formal_Type)) then
6016 goto Skip_Extra_Formal_Generation;
6019 if not Has_Discriminants (Formal_Type)
6020 and then Ekind (Formal_Type) in Private_Kind
6021 and then Present (Underlying_Type (Formal_Type))
6023 Formal_Type := Underlying_Type (Formal_Type);
6026 -- Suppress the extra formal if formal's subtype is constrained or
6027 -- indefinite, or we're compiling for Ada 2012 and the underlying
6028 -- type is tagged and limited. In Ada 2012, a limited tagged type
6029 -- can have defaulted discriminants, but 'Constrained is required
6030 -- to return True, so the formal is never needed (see AI05-0214).
6031 -- Note that this ensures consistency of calling sequences for
6032 -- dispatching operations when some types in a class have defaults
6033 -- on discriminants and others do not (and requiring the extra
6034 -- formal would introduce distributed overhead).
6036 if Has_Discriminants (Formal_Type)
6037 and then not Is_Constrained (Formal_Type)
6038 and then not Is_Indefinite_Subtype (Formal_Type)
6039 and then (Ada_Version < Ada_2012
6041 not (Is_Tagged_Type (Underlying_Type (Formal_Type))
6042 and then Is_Limited_Type (Formal_Type)))
6044 Set_Extra_Constrained
6045 (Formal, Add_Extra_Formal (Formal, Standard_Boolean, E, "O"));
6049 -- Create extra formal for supporting accessibility checking. This
6050 -- is done for both anonymous access formals and formals of named
6051 -- access types that are marked as controlling formals. The latter
6052 -- case can occur when Expand_Dispatching_Call creates a subprogram
6053 -- type and substitutes the types of access-to-class-wide actuals
6054 -- for the anonymous access-to-specific-type of controlling formals.
6055 -- Base_Type is applied because in cases where there is a null
6056 -- exclusion the formal may have an access subtype.
6058 -- This is suppressed if we specifically suppress accessibility
6059 -- checks at the package level for either the subprogram, or the
6060 -- package in which it resides. However, we do not suppress it
6061 -- simply if the scope has accessibility checks suppressed, since
6062 -- this could cause trouble when clients are compiled with a
6063 -- different suppression setting. The explicit checks at the
6064 -- package level are safe from this point of view.
6066 if (Ekind (Base_Type (Etype (Formal))) = E_Anonymous_Access_Type
6067 or else (Is_Controlling_Formal (Formal)
6068 and then Is_Access_Type (Base_Type (Etype (Formal)))))
6070 (Explicit_Suppress (E, Accessibility_Check)
6072 Explicit_Suppress (Scope (E), Accessibility_Check))
6075 or else Present (Extra_Accessibility (P_Formal)))
6077 Set_Extra_Accessibility
6078 (Formal, Add_Extra_Formal (Formal, Standard_Natural, E, "L"));
6081 -- This label is required when skipping extra formal generation for
6082 -- Unchecked_Union parameters.
6084 <<Skip_Extra_Formal_Generation>>
6086 if Present (P_Formal) then
6087 Next_Formal (P_Formal);
6090 Next_Formal (Formal);
6093 <<Test_For_BIP_Extras>>
6095 -- Ada 2005 (AI-318-02): In the case of build-in-place functions, add
6096 -- appropriate extra formals. See type Exp_Ch6.BIP_Formal_Kind.
6098 if Ada_Version >= Ada_2005 and then Is_Build_In_Place_Function (E) then
6100 Result_Subt : constant Entity_Id := Etype (E);
6102 Discard : Entity_Id;
6103 pragma Warnings (Off, Discard);
6106 -- In the case of functions with unconstrained result subtypes,
6107 -- add a 4-state formal indicating whether the return object is
6108 -- allocated by the caller (1), or should be allocated by the
6109 -- callee on the secondary stack (2), in the global heap (3), or
6110 -- in a user-defined storage pool (4). For the moment we just use
6111 -- Natural for the type of this formal. Note that this formal
6112 -- isn't usually needed in the case where the result subtype is
6113 -- constrained, but it is needed when the function has a tagged
6114 -- result, because generally such functions can be called in a
6115 -- dispatching context and such calls must be handled like calls
6116 -- to a class-wide function.
6118 if not Is_Constrained (Underlying_Type (Result_Subt))
6119 or else Is_Tagged_Type (Underlying_Type (Result_Subt))
6123 (E, Standard_Natural,
6124 E, BIP_Formal_Suffix (BIP_Alloc_Form));
6127 -- In the case of functions whose result type needs finalization,
6128 -- add an extra formal which represents the finalization master.
6130 if Needs_BIP_Finalization_Master (E) then
6133 (E, RTE (RE_Finalization_Master_Ptr),
6134 E, BIP_Formal_Suffix (BIP_Finalization_Master));
6137 -- If the result type contains tasks, we have two extra formals:
6138 -- the master of the tasks to be created, and the caller's
6139 -- activation chain.
6141 if Has_Task (Result_Subt) then
6144 (E, RTE (RE_Master_Id),
6145 E, BIP_Formal_Suffix (BIP_Master));
6148 (E, RTE (RE_Activation_Chain_Access),
6149 E, BIP_Formal_Suffix (BIP_Activation_Chain));
6152 -- All build-in-place functions get an extra formal that will be
6153 -- passed the address of the return object within the caller.
6156 Formal_Type : constant Entity_Id :=
6158 (E_Anonymous_Access_Type, E,
6159 Scope_Id => Scope (E));
6161 Set_Directly_Designated_Type (Formal_Type, Result_Subt);
6162 Set_Etype (Formal_Type, Formal_Type);
6163 Set_Depends_On_Private
6164 (Formal_Type, Has_Private_Component (Formal_Type));
6165 Set_Is_Public (Formal_Type, Is_Public (Scope (Formal_Type)));
6166 Set_Is_Access_Constant (Formal_Type, False);
6168 -- Ada 2005 (AI-50217): Propagate the attribute that indicates
6169 -- the designated type comes from the limited view (for
6170 -- back-end purposes).
6172 Set_From_With_Type (Formal_Type, From_With_Type (Result_Subt));
6174 Layout_Type (Formal_Type);
6178 (E, Formal_Type, E, BIP_Formal_Suffix (BIP_Object_Access));
6182 end Create_Extra_Formals;
6184 -----------------------------
6185 -- Enter_Overloaded_Entity --
6186 -----------------------------
6188 procedure Enter_Overloaded_Entity (S : Entity_Id) is
6189 E : Entity_Id := Current_Entity_In_Scope (S);
6190 C_E : Entity_Id := Current_Entity (S);
6194 Set_Has_Homonym (E);
6195 Set_Has_Homonym (S);
6198 Set_Is_Immediately_Visible (S);
6199 Set_Scope (S, Current_Scope);
6201 -- Chain new entity if front of homonym in current scope, so that
6202 -- homonyms are contiguous.
6207 while Homonym (C_E) /= E loop
6208 C_E := Homonym (C_E);
6211 Set_Homonym (C_E, S);
6215 Set_Current_Entity (S);
6220 Append_Entity (S, Current_Scope);
6221 Set_Public_Status (S);
6223 if Debug_Flag_E then
6224 Write_Str ("New overloaded entity chain: ");
6225 Write_Name (Chars (S));
6228 while Present (E) loop
6229 Write_Str (" "); Write_Int (Int (E));
6236 -- Generate warning for hiding
6239 and then Comes_From_Source (S)
6240 and then In_Extended_Main_Source_Unit (S)
6247 -- Warn unless genuine overloading. Do not emit warning on
6248 -- hiding predefined operators in Standard (these are either an
6249 -- (artifact of our implicit declarations, or simple noise) but
6250 -- keep warning on a operator defined on a local subtype, because
6251 -- of the real danger that different operators may be applied in
6252 -- various parts of the program.
6254 -- Note that if E and S have the same scope, there is never any
6255 -- hiding. Either the two conflict, and the program is illegal,
6256 -- or S is overriding an implicit inherited subprogram.
6258 if Scope (E) /= Scope (S)
6259 and then (not Is_Overloadable (E)
6260 or else Subtype_Conformant (E, S))
6261 and then (Is_Immediately_Visible (E)
6263 Is_Potentially_Use_Visible (S))
6265 if Scope (E) /= Standard_Standard then
6266 Error_Msg_Sloc := Sloc (E);
6267 Error_Msg_N ("declaration of & hides one#?", S);
6269 elsif Nkind (S) = N_Defining_Operator_Symbol
6271 Scope (Base_Type (Etype (First_Formal (S)))) /= Scope (S)
6274 ("declaration of & hides predefined operator?", S);
6279 end Enter_Overloaded_Entity;
6281 -----------------------------
6282 -- Check_Untagged_Equality --
6283 -----------------------------
6285 procedure Check_Untagged_Equality (Eq_Op : Entity_Id) is
6286 Typ : constant Entity_Id := Etype (First_Formal (Eq_Op));
6287 Decl : constant Node_Id := Unit_Declaration_Node (Eq_Op);
6291 if Nkind (Decl) = N_Subprogram_Declaration
6292 and then Is_Record_Type (Typ)
6293 and then not Is_Tagged_Type (Typ)
6295 -- If the type is not declared in a package, or if we are in the
6296 -- body of the package or in some other scope, the new operation is
6297 -- not primitive, and therefore legal, though suspicious. If the
6298 -- type is a generic actual (sub)type, the operation is not primitive
6299 -- either because the base type is declared elsewhere.
6301 if Is_Frozen (Typ) then
6302 if Ekind (Scope (Typ)) /= E_Package
6303 or else Scope (Typ) /= Current_Scope
6307 elsif Is_Generic_Actual_Type (Typ) then
6310 elsif In_Package_Body (Scope (Typ)) then
6312 ("equality operator must be declared "
6313 & "before type& is frozen", Eq_Op, Typ);
6315 ("\move declaration to package spec", Eq_Op);
6319 ("equality operator must be declared "
6320 & "before type& is frozen", Eq_Op, Typ);
6322 Obj_Decl := Next (Parent (Typ));
6323 while Present (Obj_Decl)
6324 and then Obj_Decl /= Decl
6326 if Nkind (Obj_Decl) = N_Object_Declaration
6327 and then Etype (Defining_Identifier (Obj_Decl)) = Typ
6329 Error_Msg_NE ("type& is frozen by declaration?",
6332 ("\an equality operator cannot be declared after this "
6333 & "point (RM 4.5.2 (9.8)) (Ada 2012))?", Obj_Decl);
6341 elsif not In_Same_List (Parent (Typ), Decl)
6342 and then not Is_Limited_Type (Typ)
6345 -- This makes it illegal to have a primitive equality declared in
6346 -- the private part if the type is visible.
6348 Error_Msg_N ("equality operator appears too late", Eq_Op);
6351 end Check_Untagged_Equality;
6353 -----------------------------
6354 -- Find_Corresponding_Spec --
6355 -----------------------------
6357 function Find_Corresponding_Spec
6359 Post_Error : Boolean := True) return Entity_Id
6361 Spec : constant Node_Id := Specification (N);
6362 Designator : constant Entity_Id := Defining_Entity (Spec);
6367 E := Current_Entity (Designator);
6368 while Present (E) loop
6370 -- We are looking for a matching spec. It must have the same scope,
6371 -- and the same name, and either be type conformant, or be the case
6372 -- of a library procedure spec and its body (which belong to one
6373 -- another regardless of whether they are type conformant or not).
6375 if Scope (E) = Current_Scope then
6376 if Current_Scope = Standard_Standard
6377 or else (Ekind (E) = Ekind (Designator)
6378 and then Type_Conformant (E, Designator))
6380 -- Within an instantiation, we know that spec and body are
6381 -- subtype conformant, because they were subtype conformant
6382 -- in the generic. We choose the subtype-conformant entity
6383 -- here as well, to resolve spurious ambiguities in the
6384 -- instance that were not present in the generic (i.e. when
6385 -- two different types are given the same actual). If we are
6386 -- looking for a spec to match a body, full conformance is
6390 Set_Convention (Designator, Convention (E));
6392 -- Skip past subprogram bodies and subprogram renamings that
6393 -- may appear to have a matching spec, but that aren't fully
6394 -- conformant with it. That can occur in cases where an
6395 -- actual type causes unrelated homographs in the instance.
6397 if Nkind_In (N, N_Subprogram_Body,
6398 N_Subprogram_Renaming_Declaration)
6399 and then Present (Homonym (E))
6400 and then not Fully_Conformant (Designator, E)
6404 elsif not Subtype_Conformant (Designator, E) then
6409 -- Ada 2012 (AI05-0165): For internally generated bodies of
6410 -- null procedures locate the internally generated spec. We
6411 -- enforce mode conformance since a tagged type may inherit
6412 -- from interfaces several null primitives which differ only
6413 -- in the mode of the formals.
6415 if not (Comes_From_Source (E))
6416 and then Is_Null_Procedure (E)
6417 and then not Mode_Conformant (Designator, E)
6421 elsif not Has_Completion (E) then
6422 if Nkind (N) /= N_Subprogram_Body_Stub then
6423 Set_Corresponding_Spec (N, E);
6426 Set_Has_Completion (E);
6429 elsif Nkind (Parent (N)) = N_Subunit then
6431 -- If this is the proper body of a subunit, the completion
6432 -- flag is set when analyzing the stub.
6436 -- If E is an internal function with a controlling result
6437 -- that was created for an operation inherited by a null
6438 -- extension, it may be overridden by a body without a previous
6439 -- spec (one more reason why these should be shunned). In that
6440 -- case remove the generated body if present, because the
6441 -- current one is the explicit overriding.
6443 elsif Ekind (E) = E_Function
6444 and then Ada_Version >= Ada_2005
6445 and then not Comes_From_Source (E)
6446 and then Has_Controlling_Result (E)
6447 and then Is_Null_Extension (Etype (E))
6448 and then Comes_From_Source (Spec)
6450 Set_Has_Completion (E, False);
6453 and then Nkind (Parent (E)) = N_Function_Specification
6456 (Unit_Declaration_Node
6457 (Corresponding_Body (Unit_Declaration_Node (E))));
6461 -- If expansion is disabled, or if the wrapper function has
6462 -- not been generated yet, this a late body overriding an
6463 -- inherited operation, or it is an overriding by some other
6464 -- declaration before the controlling result is frozen. In
6465 -- either case this is a declaration of a new entity.
6471 -- If the body already exists, then this is an error unless
6472 -- the previous declaration is the implicit declaration of a
6473 -- derived subprogram. It is also legal for an instance to
6474 -- contain type conformant overloadable declarations (but the
6475 -- generic declaration may not), per 8.3(26/2).
6477 elsif No (Alias (E))
6478 and then not Is_Intrinsic_Subprogram (E)
6479 and then not In_Instance
6482 Error_Msg_Sloc := Sloc (E);
6484 if Is_Imported (E) then
6486 ("body not allowed for imported subprogram & declared#",
6489 Error_Msg_NE ("duplicate body for & declared#", N, E);
6493 -- Child units cannot be overloaded, so a conformance mismatch
6494 -- between body and a previous spec is an error.
6496 elsif Is_Child_Unit (E)
6498 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
6500 Nkind (Parent (Unit_Declaration_Node (Designator))) =
6505 ("body of child unit does not match previous declaration", N);
6513 -- On exit, we know that no previous declaration of subprogram exists
6516 end Find_Corresponding_Spec;
6518 ----------------------
6519 -- Fully_Conformant --
6520 ----------------------
6522 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
6525 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
6527 end Fully_Conformant;
6529 ----------------------------------
6530 -- Fully_Conformant_Expressions --
6531 ----------------------------------
6533 function Fully_Conformant_Expressions
6534 (Given_E1 : Node_Id;
6535 Given_E2 : Node_Id) return Boolean
6537 E1 : constant Node_Id := Original_Node (Given_E1);
6538 E2 : constant Node_Id := Original_Node (Given_E2);
6539 -- We always test conformance on original nodes, since it is possible
6540 -- for analysis and/or expansion to make things look as though they
6541 -- conform when they do not, e.g. by converting 1+2 into 3.
6543 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
6544 renames Fully_Conformant_Expressions;
6546 function FCL (L1, L2 : List_Id) return Boolean;
6547 -- Compare elements of two lists for conformance. Elements have to
6548 -- be conformant, and actuals inserted as default parameters do not
6549 -- match explicit actuals with the same value.
6551 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
6552 -- Compare an operator node with a function call
6558 function FCL (L1, L2 : List_Id) return Boolean is
6562 if L1 = No_List then
6568 if L2 = No_List then
6574 -- Compare two lists, skipping rewrite insertions (we want to
6575 -- compare the original trees, not the expanded versions!)
6578 if Is_Rewrite_Insertion (N1) then
6580 elsif Is_Rewrite_Insertion (N2) then
6586 elsif not FCE (N1, N2) then
6599 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
6600 Actuals : constant List_Id := Parameter_Associations (Call_Node);
6605 or else Entity (Op_Node) /= Entity (Name (Call_Node))
6610 Act := First (Actuals);
6612 if Nkind (Op_Node) in N_Binary_Op then
6613 if not FCE (Left_Opnd (Op_Node), Act) then
6620 return Present (Act)
6621 and then FCE (Right_Opnd (Op_Node), Act)
6622 and then No (Next (Act));
6626 -- Start of processing for Fully_Conformant_Expressions
6629 -- Non-conformant if paren count does not match. Note: if some idiot
6630 -- complains that we don't do this right for more than 3 levels of
6631 -- parentheses, they will be treated with the respect they deserve!
6633 if Paren_Count (E1) /= Paren_Count (E2) then
6636 -- If same entities are referenced, then they are conformant even if
6637 -- they have different forms (RM 8.3.1(19-20)).
6639 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
6640 if Present (Entity (E1)) then
6641 return Entity (E1) = Entity (E2)
6642 or else (Chars (Entity (E1)) = Chars (Entity (E2))
6643 and then Ekind (Entity (E1)) = E_Discriminant
6644 and then Ekind (Entity (E2)) = E_In_Parameter);
6646 elsif Nkind (E1) = N_Expanded_Name
6647 and then Nkind (E2) = N_Expanded_Name
6648 and then Nkind (Selector_Name (E1)) = N_Character_Literal
6649 and then Nkind (Selector_Name (E2)) = N_Character_Literal
6651 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
6654 -- Identifiers in component associations don't always have
6655 -- entities, but their names must conform.
6657 return Nkind (E1) = N_Identifier
6658 and then Nkind (E2) = N_Identifier
6659 and then Chars (E1) = Chars (E2);
6662 elsif Nkind (E1) = N_Character_Literal
6663 and then Nkind (E2) = N_Expanded_Name
6665 return Nkind (Selector_Name (E2)) = N_Character_Literal
6666 and then Chars (E1) = Chars (Selector_Name (E2));
6668 elsif Nkind (E2) = N_Character_Literal
6669 and then Nkind (E1) = N_Expanded_Name
6671 return Nkind (Selector_Name (E1)) = N_Character_Literal
6672 and then Chars (E2) = Chars (Selector_Name (E1));
6674 elsif Nkind (E1) in N_Op
6675 and then Nkind (E2) = N_Function_Call
6677 return FCO (E1, E2);
6679 elsif Nkind (E2) in N_Op
6680 and then Nkind (E1) = N_Function_Call
6682 return FCO (E2, E1);
6684 -- Otherwise we must have the same syntactic entity
6686 elsif Nkind (E1) /= Nkind (E2) then
6689 -- At this point, we specialize by node type
6696 FCL (Expressions (E1), Expressions (E2))
6698 FCL (Component_Associations (E1),
6699 Component_Associations (E2));
6702 if Nkind (Expression (E1)) = N_Qualified_Expression
6704 Nkind (Expression (E2)) = N_Qualified_Expression
6706 return FCE (Expression (E1), Expression (E2));
6708 -- Check that the subtype marks and any constraints
6713 Indic1 : constant Node_Id := Expression (E1);
6714 Indic2 : constant Node_Id := Expression (E2);
6719 if Nkind (Indic1) /= N_Subtype_Indication then
6721 Nkind (Indic2) /= N_Subtype_Indication
6722 and then Entity (Indic1) = Entity (Indic2);
6724 elsif Nkind (Indic2) /= N_Subtype_Indication then
6726 Nkind (Indic1) /= N_Subtype_Indication
6727 and then Entity (Indic1) = Entity (Indic2);
6730 if Entity (Subtype_Mark (Indic1)) /=
6731 Entity (Subtype_Mark (Indic2))
6736 Elt1 := First (Constraints (Constraint (Indic1)));
6737 Elt2 := First (Constraints (Constraint (Indic2)));
6738 while Present (Elt1) and then Present (Elt2) loop
6739 if not FCE (Elt1, Elt2) then
6752 when N_Attribute_Reference =>
6754 Attribute_Name (E1) = Attribute_Name (E2)
6755 and then FCL (Expressions (E1), Expressions (E2));
6759 Entity (E1) = Entity (E2)
6760 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
6761 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
6763 when N_Short_Circuit | N_Membership_Test =>
6765 FCE (Left_Opnd (E1), Left_Opnd (E2))
6767 FCE (Right_Opnd (E1), Right_Opnd (E2));
6769 when N_Case_Expression =>
6775 if not FCE (Expression (E1), Expression (E2)) then
6779 Alt1 := First (Alternatives (E1));
6780 Alt2 := First (Alternatives (E2));
6782 if Present (Alt1) /= Present (Alt2) then
6784 elsif No (Alt1) then
6788 if not FCE (Expression (Alt1), Expression (Alt2))
6789 or else not FCL (Discrete_Choices (Alt1),
6790 Discrete_Choices (Alt2))
6801 when N_Character_Literal =>
6803 Char_Literal_Value (E1) = Char_Literal_Value (E2);
6805 when N_Component_Association =>
6807 FCL (Choices (E1), Choices (E2))
6809 FCE (Expression (E1), Expression (E2));
6811 when N_Conditional_Expression =>
6813 FCL (Expressions (E1), Expressions (E2));
6815 when N_Explicit_Dereference =>
6817 FCE (Prefix (E1), Prefix (E2));
6819 when N_Extension_Aggregate =>
6821 FCL (Expressions (E1), Expressions (E2))
6822 and then Null_Record_Present (E1) =
6823 Null_Record_Present (E2)
6824 and then FCL (Component_Associations (E1),
6825 Component_Associations (E2));
6827 when N_Function_Call =>
6829 FCE (Name (E1), Name (E2))
6831 FCL (Parameter_Associations (E1),
6832 Parameter_Associations (E2));
6834 when N_Indexed_Component =>
6836 FCE (Prefix (E1), Prefix (E2))
6838 FCL (Expressions (E1), Expressions (E2));
6840 when N_Integer_Literal =>
6841 return (Intval (E1) = Intval (E2));
6846 when N_Operator_Symbol =>
6848 Chars (E1) = Chars (E2);
6850 when N_Others_Choice =>
6853 when N_Parameter_Association =>
6855 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
6856 and then FCE (Explicit_Actual_Parameter (E1),
6857 Explicit_Actual_Parameter (E2));
6859 when N_Qualified_Expression =>
6861 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6863 FCE (Expression (E1), Expression (E2));
6865 when N_Quantified_Expression =>
6866 if not FCE (Condition (E1), Condition (E2)) then
6870 if Present (Loop_Parameter_Specification (E1))
6871 and then Present (Loop_Parameter_Specification (E2))
6874 L1 : constant Node_Id :=
6875 Loop_Parameter_Specification (E1);
6876 L2 : constant Node_Id :=
6877 Loop_Parameter_Specification (E2);
6881 Reverse_Present (L1) = Reverse_Present (L2)
6883 FCE (Defining_Identifier (L1),
6884 Defining_Identifier (L2))
6886 FCE (Discrete_Subtype_Definition (L1),
6887 Discrete_Subtype_Definition (L2));
6890 else -- quantified expression with an iterator
6892 I1 : constant Node_Id := Iterator_Specification (E1);
6893 I2 : constant Node_Id := Iterator_Specification (E2);
6897 FCE (Defining_Identifier (I1),
6898 Defining_Identifier (I2))
6900 Of_Present (I1) = Of_Present (I2)
6902 Reverse_Present (I1) = Reverse_Present (I2)
6903 and then FCE (Name (I1), Name (I2))
6904 and then FCE (Subtype_Indication (I1),
6905 Subtype_Indication (I2));
6911 FCE (Low_Bound (E1), Low_Bound (E2))
6913 FCE (High_Bound (E1), High_Bound (E2));
6915 when N_Real_Literal =>
6916 return (Realval (E1) = Realval (E2));
6918 when N_Selected_Component =>
6920 FCE (Prefix (E1), Prefix (E2))
6922 FCE (Selector_Name (E1), Selector_Name (E2));
6926 FCE (Prefix (E1), Prefix (E2))
6928 FCE (Discrete_Range (E1), Discrete_Range (E2));
6930 when N_String_Literal =>
6932 S1 : constant String_Id := Strval (E1);
6933 S2 : constant String_Id := Strval (E2);
6934 L1 : constant Nat := String_Length (S1);
6935 L2 : constant Nat := String_Length (S2);
6942 for J in 1 .. L1 loop
6943 if Get_String_Char (S1, J) /=
6944 Get_String_Char (S2, J)
6954 when N_Type_Conversion =>
6956 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6958 FCE (Expression (E1), Expression (E2));
6962 Entity (E1) = Entity (E2)
6964 FCE (Right_Opnd (E1), Right_Opnd (E2));
6966 when N_Unchecked_Type_Conversion =>
6968 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
6970 FCE (Expression (E1), Expression (E2));
6972 -- All other node types cannot appear in this context. Strictly
6973 -- we should raise a fatal internal error. Instead we just ignore
6974 -- the nodes. This means that if anyone makes a mistake in the
6975 -- expander and mucks an expression tree irretrievably, the
6976 -- result will be a failure to detect a (probably very obscure)
6977 -- case of non-conformance, which is better than bombing on some
6978 -- case where two expressions do in fact conform.
6985 end Fully_Conformant_Expressions;
6987 ----------------------------------------
6988 -- Fully_Conformant_Discrete_Subtypes --
6989 ----------------------------------------
6991 function Fully_Conformant_Discrete_Subtypes
6992 (Given_S1 : Node_Id;
6993 Given_S2 : Node_Id) return Boolean
6995 S1 : constant Node_Id := Original_Node (Given_S1);
6996 S2 : constant Node_Id := Original_Node (Given_S2);
6998 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean;
6999 -- Special-case for a bound given by a discriminant, which in the body
7000 -- is replaced with the discriminal of the enclosing type.
7002 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean;
7003 -- Check both bounds
7005 -----------------------
7006 -- Conforming_Bounds --
7007 -----------------------
7009 function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is
7011 if Is_Entity_Name (B1)
7012 and then Is_Entity_Name (B2)
7013 and then Ekind (Entity (B1)) = E_Discriminant
7015 return Chars (B1) = Chars (B2);
7018 return Fully_Conformant_Expressions (B1, B2);
7020 end Conforming_Bounds;
7022 -----------------------
7023 -- Conforming_Ranges --
7024 -----------------------
7026 function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is
7029 Conforming_Bounds (Low_Bound (R1), Low_Bound (R2))
7031 Conforming_Bounds (High_Bound (R1), High_Bound (R2));
7032 end Conforming_Ranges;
7034 -- Start of processing for Fully_Conformant_Discrete_Subtypes
7037 if Nkind (S1) /= Nkind (S2) then
7040 elsif Is_Entity_Name (S1) then
7041 return Entity (S1) = Entity (S2);
7043 elsif Nkind (S1) = N_Range then
7044 return Conforming_Ranges (S1, S2);
7046 elsif Nkind (S1) = N_Subtype_Indication then
7048 Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2))
7051 (Range_Expression (Constraint (S1)),
7052 Range_Expression (Constraint (S2)));
7056 end Fully_Conformant_Discrete_Subtypes;
7058 --------------------
7059 -- Install_Entity --
7060 --------------------
7062 procedure Install_Entity (E : Entity_Id) is
7063 Prev : constant Entity_Id := Current_Entity (E);
7065 Set_Is_Immediately_Visible (E);
7066 Set_Current_Entity (E);
7067 Set_Homonym (E, Prev);
7070 ---------------------
7071 -- Install_Formals --
7072 ---------------------
7074 procedure Install_Formals (Id : Entity_Id) is
7077 F := First_Formal (Id);
7078 while Present (F) loop
7082 end Install_Formals;
7084 -----------------------------
7085 -- Is_Interface_Conformant --
7086 -----------------------------
7088 function Is_Interface_Conformant
7089 (Tagged_Type : Entity_Id;
7090 Iface_Prim : Entity_Id;
7091 Prim : Entity_Id) return Boolean
7093 Iface : constant Entity_Id := Find_Dispatching_Type (Iface_Prim);
7094 Typ : constant Entity_Id := Find_Dispatching_Type (Prim);
7096 function Controlling_Formal (Prim : Entity_Id) return Entity_Id;
7097 -- Return the controlling formal of Prim
7099 ------------------------
7100 -- Controlling_Formal --
7101 ------------------------
7103 function Controlling_Formal (Prim : Entity_Id) return Entity_Id is
7104 E : Entity_Id := First_Entity (Prim);
7107 while Present (E) loop
7108 if Is_Formal (E) and then Is_Controlling_Formal (E) then
7116 end Controlling_Formal;
7120 Iface_Ctrl_F : constant Entity_Id := Controlling_Formal (Iface_Prim);
7121 Prim_Ctrl_F : constant Entity_Id := Controlling_Formal (Prim);
7123 -- Start of processing for Is_Interface_Conformant
7126 pragma Assert (Is_Subprogram (Iface_Prim)
7127 and then Is_Subprogram (Prim)
7128 and then Is_Dispatching_Operation (Iface_Prim)
7129 and then Is_Dispatching_Operation (Prim));
7131 pragma Assert (Is_Interface (Iface)
7132 or else (Present (Alias (Iface_Prim))
7135 (Find_Dispatching_Type (Ultimate_Alias (Iface_Prim)))));
7137 if Prim = Iface_Prim
7138 or else not Is_Subprogram (Prim)
7139 or else Ekind (Prim) /= Ekind (Iface_Prim)
7140 or else not Is_Dispatching_Operation (Prim)
7141 or else Scope (Prim) /= Scope (Tagged_Type)
7143 or else Base_Type (Typ) /= Tagged_Type
7144 or else not Primitive_Names_Match (Iface_Prim, Prim)
7148 -- The mode of the controlling formals must match
7150 elsif Present (Iface_Ctrl_F)
7151 and then Present (Prim_Ctrl_F)
7152 and then Ekind (Iface_Ctrl_F) /= Ekind (Prim_Ctrl_F)
7156 -- Case of a procedure, or a function whose result type matches the
7157 -- result type of the interface primitive, or a function that has no
7158 -- controlling result (I or access I).
7160 elsif Ekind (Iface_Prim) = E_Procedure
7161 or else Etype (Prim) = Etype (Iface_Prim)
7162 or else not Has_Controlling_Result (Prim)
7164 return Type_Conformant
7165 (Iface_Prim, Prim, Skip_Controlling_Formals => True);
7167 -- Case of a function returning an interface, or an access to one.
7168 -- Check that the return types correspond.
7170 elsif Implements_Interface (Typ, Iface) then
7171 if (Ekind (Etype (Prim)) = E_Anonymous_Access_Type)
7173 (Ekind (Etype (Iface_Prim)) = E_Anonymous_Access_Type)
7178 Type_Conformant (Prim, Iface_Prim,
7179 Skip_Controlling_Formals => True);
7185 end Is_Interface_Conformant;
7187 ---------------------------------
7188 -- Is_Non_Overriding_Operation --
7189 ---------------------------------
7191 function Is_Non_Overriding_Operation
7192 (Prev_E : Entity_Id;
7193 New_E : Entity_Id) return Boolean
7197 G_Typ : Entity_Id := Empty;
7199 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
7200 -- If F_Type is a derived type associated with a generic actual subtype,
7201 -- then return its Generic_Parent_Type attribute, else return Empty.
7203 function Types_Correspond
7204 (P_Type : Entity_Id;
7205 N_Type : Entity_Id) return Boolean;
7206 -- Returns true if and only if the types (or designated types in the
7207 -- case of anonymous access types) are the same or N_Type is derived
7208 -- directly or indirectly from P_Type.
7210 -----------------------------
7211 -- Get_Generic_Parent_Type --
7212 -----------------------------
7214 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
7219 if Is_Derived_Type (F_Typ)
7220 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
7222 -- The tree must be traversed to determine the parent subtype in
7223 -- the generic unit, which unfortunately isn't always available
7224 -- via semantic attributes. ??? (Note: The use of Original_Node
7225 -- is needed for cases where a full derived type has been
7228 Indic := Subtype_Indication
7229 (Type_Definition (Original_Node (Parent (F_Typ))));
7231 if Nkind (Indic) = N_Subtype_Indication then
7232 G_Typ := Entity (Subtype_Mark (Indic));
7234 G_Typ := Entity (Indic);
7237 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
7238 and then Present (Generic_Parent_Type (Parent (G_Typ)))
7240 return Generic_Parent_Type (Parent (G_Typ));
7245 end Get_Generic_Parent_Type;
7247 ----------------------
7248 -- Types_Correspond --
7249 ----------------------
7251 function Types_Correspond
7252 (P_Type : Entity_Id;
7253 N_Type : Entity_Id) return Boolean
7255 Prev_Type : Entity_Id := Base_Type (P_Type);
7256 New_Type : Entity_Id := Base_Type (N_Type);
7259 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
7260 Prev_Type := Designated_Type (Prev_Type);
7263 if Ekind (New_Type) = E_Anonymous_Access_Type then
7264 New_Type := Designated_Type (New_Type);
7267 if Prev_Type = New_Type then
7270 elsif not Is_Class_Wide_Type (New_Type) then
7271 while Etype (New_Type) /= New_Type loop
7272 New_Type := Etype (New_Type);
7273 if New_Type = Prev_Type then
7279 end Types_Correspond;
7281 -- Start of processing for Is_Non_Overriding_Operation
7284 -- In the case where both operations are implicit derived subprograms
7285 -- then neither overrides the other. This can only occur in certain
7286 -- obscure cases (e.g., derivation from homographs created in a generic
7289 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
7292 elsif Ekind (Current_Scope) = E_Package
7293 and then Is_Generic_Instance (Current_Scope)
7294 and then In_Private_Part (Current_Scope)
7295 and then Comes_From_Source (New_E)
7297 -- We examine the formals and result subtype of the inherited
7298 -- operation, to determine whether their type is derived from (the
7299 -- instance of) a generic type.
7301 Formal := First_Formal (Prev_E);
7302 while Present (Formal) loop
7303 F_Typ := Base_Type (Etype (Formal));
7305 if Ekind (F_Typ) = E_Anonymous_Access_Type then
7306 F_Typ := Designated_Type (F_Typ);
7309 G_Typ := Get_Generic_Parent_Type (F_Typ);
7311 Next_Formal (Formal);
7314 if No (G_Typ) and then Ekind (Prev_E) = E_Function then
7315 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
7322 -- If the generic type is a private type, then the original operation
7323 -- was not overriding in the generic, because there was no primitive
7324 -- operation to override.
7326 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
7327 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
7328 N_Formal_Private_Type_Definition
7332 -- The generic parent type is the ancestor of a formal derived
7333 -- type declaration. We need to check whether it has a primitive
7334 -- operation that should be overridden by New_E in the generic.
7338 P_Formal : Entity_Id;
7339 N_Formal : Entity_Id;
7343 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
7346 while Present (Prim_Elt) loop
7347 P_Prim := Node (Prim_Elt);
7349 if Chars (P_Prim) = Chars (New_E)
7350 and then Ekind (P_Prim) = Ekind (New_E)
7352 P_Formal := First_Formal (P_Prim);
7353 N_Formal := First_Formal (New_E);
7354 while Present (P_Formal) and then Present (N_Formal) loop
7355 P_Typ := Etype (P_Formal);
7356 N_Typ := Etype (N_Formal);
7358 if not Types_Correspond (P_Typ, N_Typ) then
7362 Next_Entity (P_Formal);
7363 Next_Entity (N_Formal);
7366 -- Found a matching primitive operation belonging to the
7367 -- formal ancestor type, so the new subprogram is
7371 and then No (N_Formal)
7372 and then (Ekind (New_E) /= E_Function
7375 (Etype (P_Prim), Etype (New_E)))
7381 Next_Elmt (Prim_Elt);
7384 -- If no match found, then the new subprogram does not
7385 -- override in the generic (nor in the instance).
7393 end Is_Non_Overriding_Operation;
7395 -------------------------------------
7396 -- List_Inherited_Pre_Post_Aspects --
7397 -------------------------------------
7399 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id) is
7401 if Opt.List_Inherited_Aspects
7402 and then (Is_Subprogram (E) or else Is_Generic_Subprogram (E))
7405 Inherited : constant Subprogram_List :=
7406 Inherited_Subprograms (E);
7410 for J in Inherited'Range loop
7411 P := Spec_PPC_List (Contract (Inherited (J)));
7413 while Present (P) loop
7414 Error_Msg_Sloc := Sloc (P);
7416 if Class_Present (P) and then not Split_PPC (P) then
7417 if Pragma_Name (P) = Name_Precondition then
7419 ("?info: & inherits `Pre''Class` aspect from #", E);
7422 ("?info: & inherits `Post''Class` aspect from #", E);
7426 P := Next_Pragma (P);
7431 end List_Inherited_Pre_Post_Aspects;
7433 ------------------------------
7434 -- Make_Inequality_Operator --
7435 ------------------------------
7437 -- S is the defining identifier of an equality operator. We build a
7438 -- subprogram declaration with the right signature. This operation is
7439 -- intrinsic, because it is always expanded as the negation of the
7440 -- call to the equality function.
7442 procedure Make_Inequality_Operator (S : Entity_Id) is
7443 Loc : constant Source_Ptr := Sloc (S);
7446 Op_Name : Entity_Id;
7448 FF : constant Entity_Id := First_Formal (S);
7449 NF : constant Entity_Id := Next_Formal (FF);
7452 -- Check that equality was properly defined, ignore call if not
7459 A : constant Entity_Id :=
7460 Make_Defining_Identifier (Sloc (FF),
7461 Chars => Chars (FF));
7463 B : constant Entity_Id :=
7464 Make_Defining_Identifier (Sloc (NF),
7465 Chars => Chars (NF));
7468 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
7470 Formals := New_List (
7471 Make_Parameter_Specification (Loc,
7472 Defining_Identifier => A,
7474 New_Reference_To (Etype (First_Formal (S)),
7475 Sloc (Etype (First_Formal (S))))),
7477 Make_Parameter_Specification (Loc,
7478 Defining_Identifier => B,
7480 New_Reference_To (Etype (Next_Formal (First_Formal (S))),
7481 Sloc (Etype (Next_Formal (First_Formal (S)))))));
7484 Make_Subprogram_Declaration (Loc,
7486 Make_Function_Specification (Loc,
7487 Defining_Unit_Name => Op_Name,
7488 Parameter_Specifications => Formals,
7489 Result_Definition =>
7490 New_Reference_To (Standard_Boolean, Loc)));
7492 -- Insert inequality right after equality if it is explicit or after
7493 -- the derived type when implicit. These entities are created only
7494 -- for visibility purposes, and eventually replaced in the course of
7495 -- expansion, so they do not need to be attached to the tree and seen
7496 -- by the back-end. Keeping them internal also avoids spurious
7497 -- freezing problems. The declaration is inserted in the tree for
7498 -- analysis, and removed afterwards. If the equality operator comes
7499 -- from an explicit declaration, attach the inequality immediately
7500 -- after. Else the equality is inherited from a derived type
7501 -- declaration, so insert inequality after that declaration.
7503 if No (Alias (S)) then
7504 Insert_After (Unit_Declaration_Node (S), Decl);
7505 elsif Is_List_Member (Parent (S)) then
7506 Insert_After (Parent (S), Decl);
7508 Insert_After (Parent (Etype (First_Formal (S))), Decl);
7511 Mark_Rewrite_Insertion (Decl);
7512 Set_Is_Intrinsic_Subprogram (Op_Name);
7515 Set_Has_Completion (Op_Name);
7516 Set_Corresponding_Equality (Op_Name, S);
7517 Set_Is_Abstract_Subprogram (Op_Name, Is_Abstract_Subprogram (S));
7519 end Make_Inequality_Operator;
7521 ----------------------
7522 -- May_Need_Actuals --
7523 ----------------------
7525 procedure May_Need_Actuals (Fun : Entity_Id) is
7530 F := First_Formal (Fun);
7532 while Present (F) loop
7533 if No (Default_Value (F)) then
7541 Set_Needs_No_Actuals (Fun, B);
7542 end May_Need_Actuals;
7544 ---------------------
7545 -- Mode_Conformant --
7546 ---------------------
7548 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
7551 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
7553 end Mode_Conformant;
7555 ---------------------------
7556 -- New_Overloaded_Entity --
7557 ---------------------------
7559 procedure New_Overloaded_Entity
7561 Derived_Type : Entity_Id := Empty)
7563 Overridden_Subp : Entity_Id := Empty;
7564 -- Set if the current scope has an operation that is type-conformant
7565 -- with S, and becomes hidden by S.
7567 Is_Primitive_Subp : Boolean;
7568 -- Set to True if the new subprogram is primitive
7571 -- Entity that S overrides
7573 Prev_Vis : Entity_Id := Empty;
7574 -- Predecessor of E in Homonym chain
7576 procedure Check_For_Primitive_Subprogram
7577 (Is_Primitive : out Boolean;
7578 Is_Overriding : Boolean := False);
7579 -- If the subprogram being analyzed is a primitive operation of the type
7580 -- of a formal or result, set the Has_Primitive_Operations flag on the
7581 -- type, and set Is_Primitive to True (otherwise set to False). Set the
7582 -- corresponding flag on the entity itself for later use.
7584 procedure Check_Synchronized_Overriding
7585 (Def_Id : Entity_Id;
7586 Overridden_Subp : out Entity_Id);
7587 -- First determine if Def_Id is an entry or a subprogram either defined
7588 -- in the scope of a task or protected type, or is a primitive of such
7589 -- a type. Check whether Def_Id overrides a subprogram of an interface
7590 -- implemented by the synchronized type, return the overridden entity
7593 function Is_Private_Declaration (E : Entity_Id) return Boolean;
7594 -- Check that E is declared in the private part of the current package,
7595 -- or in the package body, where it may hide a previous declaration.
7596 -- We can't use In_Private_Part by itself because this flag is also
7597 -- set when freezing entities, so we must examine the place of the
7598 -- declaration in the tree, and recognize wrapper packages as well.
7600 function Is_Overriding_Alias
7602 New_E : Entity_Id) return Boolean;
7603 -- Check whether new subprogram and old subprogram are both inherited
7604 -- from subprograms that have distinct dispatch table entries. This can
7605 -- occur with derivations from instances with accidental homonyms.
7606 -- The function is conservative given that the converse is only true
7607 -- within instances that contain accidental overloadings.
7609 ------------------------------------
7610 -- Check_For_Primitive_Subprogram --
7611 ------------------------------------
7613 procedure Check_For_Primitive_Subprogram
7614 (Is_Primitive : out Boolean;
7615 Is_Overriding : Boolean := False)
7621 function Visible_Part_Type (T : Entity_Id) return Boolean;
7622 -- Returns true if T is declared in the visible part of the current
7623 -- package scope; otherwise returns false. Assumes that T is declared
7626 procedure Check_Private_Overriding (T : Entity_Id);
7627 -- Checks that if a primitive abstract subprogram of a visible
7628 -- abstract type is declared in a private part, then it must override
7629 -- an abstract subprogram declared in the visible part. Also checks
7630 -- that if a primitive function with a controlling result is declared
7631 -- in a private part, then it must override a function declared in
7632 -- the visible part.
7634 ------------------------------
7635 -- Check_Private_Overriding --
7636 ------------------------------
7638 procedure Check_Private_Overriding (T : Entity_Id) is
7640 if Is_Package_Or_Generic_Package (Current_Scope)
7641 and then In_Private_Part (Current_Scope)
7642 and then Visible_Part_Type (T)
7643 and then not In_Instance
7645 if Is_Abstract_Type (T)
7646 and then Is_Abstract_Subprogram (S)
7647 and then (not Is_Overriding
7648 or else not Is_Abstract_Subprogram (E))
7651 ("abstract subprograms must be visible "
7652 & "(RM 3.9.3(10))!", S);
7654 elsif Ekind (S) = E_Function
7655 and then not Is_Overriding
7657 if Is_Tagged_Type (T)
7658 and then T = Base_Type (Etype (S))
7661 ("private function with tagged result must"
7662 & " override visible-part function", S);
7664 ("\move subprogram to the visible part"
7665 & " (RM 3.9.3(10))", S);
7667 -- AI05-0073: extend this test to the case of a function
7668 -- with a controlling access result.
7670 elsif Ekind (Etype (S)) = E_Anonymous_Access_Type
7671 and then Is_Tagged_Type (Designated_Type (Etype (S)))
7673 not Is_Class_Wide_Type (Designated_Type (Etype (S)))
7674 and then Ada_Version >= Ada_2012
7677 ("private function with controlling access result "
7678 & "must override visible-part function", S);
7680 ("\move subprogram to the visible part"
7681 & " (RM 3.9.3(10))", S);
7685 end Check_Private_Overriding;
7687 -----------------------
7688 -- Visible_Part_Type --
7689 -----------------------
7691 function Visible_Part_Type (T : Entity_Id) return Boolean is
7692 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
7696 -- If the entity is a private type, then it must be declared in a
7699 if Ekind (T) in Private_Kind then
7703 -- Otherwise, we traverse the visible part looking for its
7704 -- corresponding declaration. We cannot use the declaration
7705 -- node directly because in the private part the entity of a
7706 -- private type is the one in the full view, which does not
7707 -- indicate that it is the completion of something visible.
7709 N := First (Visible_Declarations (Specification (P)));
7710 while Present (N) loop
7711 if Nkind (N) = N_Full_Type_Declaration
7712 and then Present (Defining_Identifier (N))
7713 and then T = Defining_Identifier (N)
7717 elsif Nkind_In (N, N_Private_Type_Declaration,
7718 N_Private_Extension_Declaration)
7719 and then Present (Defining_Identifier (N))
7720 and then T = Full_View (Defining_Identifier (N))
7729 end Visible_Part_Type;
7731 -- Start of processing for Check_For_Primitive_Subprogram
7734 Is_Primitive := False;
7736 if not Comes_From_Source (S) then
7739 -- If subprogram is at library level, it is not primitive operation
7741 elsif Current_Scope = Standard_Standard then
7744 elsif (Is_Package_Or_Generic_Package (Current_Scope)
7745 and then not In_Package_Body (Current_Scope))
7746 or else Is_Overriding
7748 -- For function, check return type
7750 if Ekind (S) = E_Function then
7751 if Ekind (Etype (S)) = E_Anonymous_Access_Type then
7752 F_Typ := Designated_Type (Etype (S));
7757 B_Typ := Base_Type (F_Typ);
7759 if Scope (B_Typ) = Current_Scope
7760 and then not Is_Class_Wide_Type (B_Typ)
7761 and then not Is_Generic_Type (B_Typ)
7763 Is_Primitive := True;
7764 Set_Has_Primitive_Operations (B_Typ);
7765 Set_Is_Primitive (S);
7766 Check_Private_Overriding (B_Typ);
7770 -- For all subprograms, check formals
7772 Formal := First_Formal (S);
7773 while Present (Formal) loop
7774 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
7775 F_Typ := Designated_Type (Etype (Formal));
7777 F_Typ := Etype (Formal);
7780 B_Typ := Base_Type (F_Typ);
7782 if Ekind (B_Typ) = E_Access_Subtype then
7783 B_Typ := Base_Type (B_Typ);
7786 if Scope (B_Typ) = Current_Scope
7787 and then not Is_Class_Wide_Type (B_Typ)
7788 and then not Is_Generic_Type (B_Typ)
7790 Is_Primitive := True;
7791 Set_Is_Primitive (S);
7792 Set_Has_Primitive_Operations (B_Typ);
7793 Check_Private_Overriding (B_Typ);
7796 Next_Formal (Formal);
7799 end Check_For_Primitive_Subprogram;
7801 -----------------------------------
7802 -- Check_Synchronized_Overriding --
7803 -----------------------------------
7805 procedure Check_Synchronized_Overriding
7806 (Def_Id : Entity_Id;
7807 Overridden_Subp : out Entity_Id)
7809 Ifaces_List : Elist_Id;
7813 function Matches_Prefixed_View_Profile
7814 (Prim_Params : List_Id;
7815 Iface_Params : List_Id) return Boolean;
7816 -- Determine whether a subprogram's parameter profile Prim_Params
7817 -- matches that of a potentially overridden interface subprogram
7818 -- Iface_Params. Also determine if the type of first parameter of
7819 -- Iface_Params is an implemented interface.
7821 -----------------------------------
7822 -- Matches_Prefixed_View_Profile --
7823 -----------------------------------
7825 function Matches_Prefixed_View_Profile
7826 (Prim_Params : List_Id;
7827 Iface_Params : List_Id) return Boolean
7829 Iface_Id : Entity_Id;
7830 Iface_Param : Node_Id;
7831 Iface_Typ : Entity_Id;
7832 Prim_Id : Entity_Id;
7833 Prim_Param : Node_Id;
7834 Prim_Typ : Entity_Id;
7836 function Is_Implemented
7837 (Ifaces_List : Elist_Id;
7838 Iface : Entity_Id) return Boolean;
7839 -- Determine if Iface is implemented by the current task or
7842 --------------------
7843 -- Is_Implemented --
7844 --------------------
7846 function Is_Implemented
7847 (Ifaces_List : Elist_Id;
7848 Iface : Entity_Id) return Boolean
7850 Iface_Elmt : Elmt_Id;
7853 Iface_Elmt := First_Elmt (Ifaces_List);
7854 while Present (Iface_Elmt) loop
7855 if Node (Iface_Elmt) = Iface then
7859 Next_Elmt (Iface_Elmt);
7865 -- Start of processing for Matches_Prefixed_View_Profile
7868 Iface_Param := First (Iface_Params);
7869 Iface_Typ := Etype (Defining_Identifier (Iface_Param));
7871 if Is_Access_Type (Iface_Typ) then
7872 Iface_Typ := Designated_Type (Iface_Typ);
7875 Prim_Param := First (Prim_Params);
7877 -- The first parameter of the potentially overridden subprogram
7878 -- must be an interface implemented by Prim.
7880 if not Is_Interface (Iface_Typ)
7881 or else not Is_Implemented (Ifaces_List, Iface_Typ)
7886 -- The checks on the object parameters are done, move onto the
7887 -- rest of the parameters.
7889 if not In_Scope then
7890 Prim_Param := Next (Prim_Param);
7893 Iface_Param := Next (Iface_Param);
7894 while Present (Iface_Param) and then Present (Prim_Param) loop
7895 Iface_Id := Defining_Identifier (Iface_Param);
7896 Iface_Typ := Find_Parameter_Type (Iface_Param);
7898 Prim_Id := Defining_Identifier (Prim_Param);
7899 Prim_Typ := Find_Parameter_Type (Prim_Param);
7901 if Ekind (Iface_Typ) = E_Anonymous_Access_Type
7902 and then Ekind (Prim_Typ) = E_Anonymous_Access_Type
7903 and then Is_Concurrent_Type (Designated_Type (Prim_Typ))
7905 Iface_Typ := Designated_Type (Iface_Typ);
7906 Prim_Typ := Designated_Type (Prim_Typ);
7909 -- Case of multiple interface types inside a parameter profile
7911 -- (Obj_Param : in out Iface; ...; Param : Iface)
7913 -- If the interface type is implemented, then the matching type
7914 -- in the primitive should be the implementing record type.
7916 if Ekind (Iface_Typ) = E_Record_Type
7917 and then Is_Interface (Iface_Typ)
7918 and then Is_Implemented (Ifaces_List, Iface_Typ)
7920 if Prim_Typ /= Typ then
7924 -- The two parameters must be both mode and subtype conformant
7926 elsif Ekind (Iface_Id) /= Ekind (Prim_Id)
7928 Conforming_Types (Iface_Typ, Prim_Typ, Subtype_Conformant)
7937 -- One of the two lists contains more parameters than the other
7939 if Present (Iface_Param) or else Present (Prim_Param) then
7944 end Matches_Prefixed_View_Profile;
7946 -- Start of processing for Check_Synchronized_Overriding
7949 Overridden_Subp := Empty;
7951 -- Def_Id must be an entry or a subprogram. We should skip predefined
7952 -- primitives internally generated by the frontend; however at this
7953 -- stage predefined primitives are still not fully decorated. As a
7954 -- minor optimization we skip here internally generated subprograms.
7956 if (Ekind (Def_Id) /= E_Entry
7957 and then Ekind (Def_Id) /= E_Function
7958 and then Ekind (Def_Id) /= E_Procedure)
7959 or else not Comes_From_Source (Def_Id)
7964 -- Search for the concurrent declaration since it contains the list
7965 -- of all implemented interfaces. In this case, the subprogram is
7966 -- declared within the scope of a protected or a task type.
7968 if Present (Scope (Def_Id))
7969 and then Is_Concurrent_Type (Scope (Def_Id))
7970 and then not Is_Generic_Actual_Type (Scope (Def_Id))
7972 Typ := Scope (Def_Id);
7975 -- The enclosing scope is not a synchronized type and the subprogram
7978 elsif No (First_Formal (Def_Id)) then
7981 -- The subprogram has formals and hence it may be a primitive of a
7985 Typ := Etype (First_Formal (Def_Id));
7987 if Is_Access_Type (Typ) then
7988 Typ := Directly_Designated_Type (Typ);
7991 if Is_Concurrent_Type (Typ)
7992 and then not Is_Generic_Actual_Type (Typ)
7996 -- This case occurs when the concurrent type is declared within
7997 -- a generic unit. As a result the corresponding record has been
7998 -- built and used as the type of the first formal, we just have
7999 -- to retrieve the corresponding concurrent type.
8001 elsif Is_Concurrent_Record_Type (Typ)
8002 and then not Is_Class_Wide_Type (Typ)
8003 and then Present (Corresponding_Concurrent_Type (Typ))
8005 Typ := Corresponding_Concurrent_Type (Typ);
8013 -- There is no overriding to check if is an inherited operation in a
8014 -- type derivation on for a generic actual.
8016 Collect_Interfaces (Typ, Ifaces_List);
8018 if Is_Empty_Elmt_List (Ifaces_List) then
8022 -- Determine whether entry or subprogram Def_Id overrides a primitive
8023 -- operation that belongs to one of the interfaces in Ifaces_List.
8026 Candidate : Entity_Id := Empty;
8027 Hom : Entity_Id := Empty;
8028 Iface_Typ : Entity_Id;
8029 Subp : Entity_Id := Empty;
8032 -- Traverse the homonym chain, looking for a potentially
8033 -- overridden subprogram that belongs to an implemented
8036 Hom := Current_Entity_In_Scope (Def_Id);
8037 while Present (Hom) loop
8041 or else not Is_Overloadable (Subp)
8042 or else not Is_Primitive (Subp)
8043 or else not Is_Dispatching_Operation (Subp)
8044 or else not Present (Find_Dispatching_Type (Subp))
8045 or else not Is_Interface (Find_Dispatching_Type (Subp))
8049 -- Entries and procedures can override abstract or null
8050 -- interface procedures.
8052 elsif (Ekind (Def_Id) = E_Procedure
8053 or else Ekind (Def_Id) = E_Entry)
8054 and then Ekind (Subp) = E_Procedure
8055 and then Matches_Prefixed_View_Profile
8056 (Parameter_Specifications (Parent (Def_Id)),
8057 Parameter_Specifications (Parent (Subp)))
8061 -- For an overridden subprogram Subp, check whether the mode
8062 -- of its first parameter is correct depending on the kind
8063 -- of synchronized type.
8066 Formal : constant Node_Id := First_Formal (Candidate);
8069 -- In order for an entry or a protected procedure to
8070 -- override, the first parameter of the overridden
8071 -- routine must be of mode "out", "in out" or
8072 -- access-to-variable.
8074 if (Ekind (Candidate) = E_Entry
8075 or else Ekind (Candidate) = E_Procedure)
8076 and then Is_Protected_Type (Typ)
8077 and then Ekind (Formal) /= E_In_Out_Parameter
8078 and then Ekind (Formal) /= E_Out_Parameter
8079 and then Nkind (Parameter_Type (Parent (Formal)))
8080 /= N_Access_Definition
8084 -- All other cases are OK since a task entry or routine
8085 -- does not have a restriction on the mode of the first
8086 -- parameter of the overridden interface routine.
8089 Overridden_Subp := Candidate;
8094 -- Functions can override abstract interface functions
8096 elsif Ekind (Def_Id) = E_Function
8097 and then Ekind (Subp) = E_Function
8098 and then Matches_Prefixed_View_Profile
8099 (Parameter_Specifications (Parent (Def_Id)),
8100 Parameter_Specifications (Parent (Subp)))
8101 and then Etype (Result_Definition (Parent (Def_Id))) =
8102 Etype (Result_Definition (Parent (Subp)))
8104 Overridden_Subp := Subp;
8108 Hom := Homonym (Hom);
8111 -- After examining all candidates for overriding, we are left with
8112 -- the best match which is a mode incompatible interface routine.
8113 -- Do not emit an error if the Expander is active since this error
8114 -- will be detected later on after all concurrent types are
8115 -- expanded and all wrappers are built. This check is meant for
8116 -- spec-only compilations.
8118 if Present (Candidate) and then not Expander_Active then
8120 Find_Parameter_Type (Parent (First_Formal (Candidate)));
8122 -- Def_Id is primitive of a protected type, declared inside the
8123 -- type, and the candidate is primitive of a limited or
8124 -- synchronized interface.
8127 and then Is_Protected_Type (Typ)
8129 (Is_Limited_Interface (Iface_Typ)
8130 or else Is_Protected_Interface (Iface_Typ)
8131 or else Is_Synchronized_Interface (Iface_Typ)
8132 or else Is_Task_Interface (Iface_Typ))
8134 Error_Msg_PT (Parent (Typ), Candidate);
8138 Overridden_Subp := Candidate;
8141 end Check_Synchronized_Overriding;
8143 ----------------------------
8144 -- Is_Private_Declaration --
8145 ----------------------------
8147 function Is_Private_Declaration (E : Entity_Id) return Boolean is
8148 Priv_Decls : List_Id;
8149 Decl : constant Node_Id := Unit_Declaration_Node (E);
8152 if Is_Package_Or_Generic_Package (Current_Scope)
8153 and then In_Private_Part (Current_Scope)
8156 Private_Declarations (
8157 Specification (Unit_Declaration_Node (Current_Scope)));
8159 return In_Package_Body (Current_Scope)
8161 (Is_List_Member (Decl)
8162 and then List_Containing (Decl) = Priv_Decls)
8163 or else (Nkind (Parent (Decl)) = N_Package_Specification
8166 (Defining_Entity (Parent (Decl)))
8167 and then List_Containing (Parent (Parent (Decl)))
8172 end Is_Private_Declaration;
8174 --------------------------
8175 -- Is_Overriding_Alias --
8176 --------------------------
8178 function Is_Overriding_Alias
8180 New_E : Entity_Id) return Boolean
8182 AO : constant Entity_Id := Alias (Old_E);
8183 AN : constant Entity_Id := Alias (New_E);
8186 return Scope (AO) /= Scope (AN)
8187 or else No (DTC_Entity (AO))
8188 or else No (DTC_Entity (AN))
8189 or else DT_Position (AO) = DT_Position (AN);
8190 end Is_Overriding_Alias;
8192 -- Start of processing for New_Overloaded_Entity
8195 -- We need to look for an entity that S may override. This must be a
8196 -- homonym in the current scope, so we look for the first homonym of
8197 -- S in the current scope as the starting point for the search.
8199 E := Current_Entity_In_Scope (S);
8201 -- Ada 2005 (AI-251): Derivation of abstract interface primitives.
8202 -- They are directly added to the list of primitive operations of
8203 -- Derived_Type, unless this is a rederivation in the private part
8204 -- of an operation that was already derived in the visible part of
8205 -- the current package.
8207 if Ada_Version >= Ada_2005
8208 and then Present (Derived_Type)
8209 and then Present (Alias (S))
8210 and then Is_Dispatching_Operation (Alias (S))
8211 and then Present (Find_Dispatching_Type (Alias (S)))
8212 and then Is_Interface (Find_Dispatching_Type (Alias (S)))
8214 -- For private types, when the full-view is processed we propagate to
8215 -- the full view the non-overridden entities whose attribute "alias"
8216 -- references an interface primitive. These entities were added by
8217 -- Derive_Subprograms to ensure that interface primitives are
8220 -- Inside_Freeze_Actions is non zero when S corresponds with an
8221 -- internal entity that links an interface primitive with its
8222 -- covering primitive through attribute Interface_Alias (see
8223 -- Add_Internal_Interface_Entities).
8225 if Inside_Freezing_Actions = 0
8226 and then Is_Package_Or_Generic_Package (Current_Scope)
8227 and then In_Private_Part (Current_Scope)
8228 and then Nkind (Parent (E)) = N_Private_Extension_Declaration
8229 and then Nkind (Parent (S)) = N_Full_Type_Declaration
8230 and then Full_View (Defining_Identifier (Parent (E)))
8231 = Defining_Identifier (Parent (S))
8232 and then Alias (E) = Alias (S)
8234 Check_Operation_From_Private_View (S, E);
8235 Set_Is_Dispatching_Operation (S);
8240 Enter_Overloaded_Entity (S);
8241 Check_Dispatching_Operation (S, Empty);
8242 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8248 -- If there is no homonym then this is definitely not overriding
8251 Enter_Overloaded_Entity (S);
8252 Check_Dispatching_Operation (S, Empty);
8253 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8255 -- If subprogram has an explicit declaration, check whether it
8256 -- has an overriding indicator.
8258 if Comes_From_Source (S) then
8259 Check_Synchronized_Overriding (S, Overridden_Subp);
8261 -- (Ada 2012: AI05-0125-1): If S is a dispatching operation then
8262 -- it may have overridden some hidden inherited primitive. Update
8263 -- Overridden_Subp to avoid spurious errors when checking the
8264 -- overriding indicator.
8266 if Ada_Version >= Ada_2012
8267 and then No (Overridden_Subp)
8268 and then Is_Dispatching_Operation (S)
8269 and then Present (Overridden_Operation (S))
8271 Overridden_Subp := Overridden_Operation (S);
8274 Check_Overriding_Indicator
8275 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8278 -- If there is a homonym that is not overloadable, then we have an
8279 -- error, except for the special cases checked explicitly below.
8281 elsif not Is_Overloadable (E) then
8283 -- Check for spurious conflict produced by a subprogram that has the
8284 -- same name as that of the enclosing generic package. The conflict
8285 -- occurs within an instance, between the subprogram and the renaming
8286 -- declaration for the package. After the subprogram, the package
8287 -- renaming declaration becomes hidden.
8289 if Ekind (E) = E_Package
8290 and then Present (Renamed_Object (E))
8291 and then Renamed_Object (E) = Current_Scope
8292 and then Nkind (Parent (Renamed_Object (E))) =
8293 N_Package_Specification
8294 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
8297 Set_Is_Immediately_Visible (E, False);
8298 Enter_Overloaded_Entity (S);
8299 Set_Homonym (S, Homonym (E));
8300 Check_Dispatching_Operation (S, Empty);
8301 Check_Overriding_Indicator (S, Empty, Is_Primitive => False);
8303 -- If the subprogram is implicit it is hidden by the previous
8304 -- declaration. However if it is dispatching, it must appear in the
8305 -- dispatch table anyway, because it can be dispatched to even if it
8306 -- cannot be called directly.
8308 elsif Present (Alias (S)) and then not Comes_From_Source (S) then
8309 Set_Scope (S, Current_Scope);
8311 if Is_Dispatching_Operation (Alias (S)) then
8312 Check_Dispatching_Operation (S, Empty);
8318 Error_Msg_Sloc := Sloc (E);
8320 -- Generate message, with useful additional warning if in generic
8322 if Is_Generic_Unit (E) then
8323 Error_Msg_N ("previous generic unit cannot be overloaded", S);
8324 Error_Msg_N ("\& conflicts with declaration#", S);
8326 Error_Msg_N ("& conflicts with declaration#", S);
8332 -- E exists and is overloadable
8335 Check_Synchronized_Overriding (S, Overridden_Subp);
8337 -- Loop through E and its homonyms to determine if any of them is
8338 -- the candidate for overriding by S.
8340 while Present (E) loop
8342 -- Definitely not interesting if not in the current scope
8344 if Scope (E) /= Current_Scope then
8347 -- Ada 2012 (AI05-0165): For internally generated bodies of
8348 -- null procedures locate the internally generated spec. We
8349 -- enforce mode conformance since a tagged type may inherit
8350 -- from interfaces several null primitives which differ only
8351 -- in the mode of the formals.
8353 elsif not Comes_From_Source (S)
8354 and then Is_Null_Procedure (S)
8355 and then not Mode_Conformant (E, S)
8359 -- Check if we have type conformance
8361 elsif Type_Conformant (E, S) then
8363 -- If the old and new entities have the same profile and one
8364 -- is not the body of the other, then this is an error, unless
8365 -- one of them is implicitly declared.
8367 -- There are some cases when both can be implicit, for example
8368 -- when both a literal and a function that overrides it are
8369 -- inherited in a derivation, or when an inherited operation
8370 -- of a tagged full type overrides the inherited operation of
8371 -- a private extension. Ada 83 had a special rule for the
8372 -- literal case. In Ada95, the later implicit operation hides
8373 -- the former, and the literal is always the former. In the
8374 -- odd case where both are derived operations declared at the
8375 -- same point, both operations should be declared, and in that
8376 -- case we bypass the following test and proceed to the next
8377 -- part. This can only occur for certain obscure cases in
8378 -- instances, when an operation on a type derived from a formal
8379 -- private type does not override a homograph inherited from
8380 -- the actual. In subsequent derivations of such a type, the
8381 -- DT positions of these operations remain distinct, if they
8384 if Present (Alias (S))
8385 and then (No (Alias (E))
8386 or else Comes_From_Source (E)
8387 or else Is_Abstract_Subprogram (S)
8389 (Is_Dispatching_Operation (E)
8390 and then Is_Overriding_Alias (E, S)))
8391 and then Ekind (E) /= E_Enumeration_Literal
8393 -- When an derived operation is overloaded it may be due to
8394 -- the fact that the full view of a private extension
8395 -- re-inherits. It has to be dealt with.
8397 if Is_Package_Or_Generic_Package (Current_Scope)
8398 and then In_Private_Part (Current_Scope)
8400 Check_Operation_From_Private_View (S, E);
8403 -- In any case the implicit operation remains hidden by the
8404 -- existing declaration, which is overriding. Indicate that
8405 -- E overrides the operation from which S is inherited.
8407 if Present (Alias (S)) then
8408 Set_Overridden_Operation (E, Alias (S));
8410 Set_Overridden_Operation (E, S);
8413 if Comes_From_Source (E) then
8414 Check_Overriding_Indicator (E, S, Is_Primitive => False);
8419 -- Within an instance, the renaming declarations for actual
8420 -- subprograms may become ambiguous, but they do not hide each
8423 elsif Ekind (E) /= E_Entry
8424 and then not Comes_From_Source (E)
8425 and then not Is_Generic_Instance (E)
8426 and then (Present (Alias (E))
8427 or else Is_Intrinsic_Subprogram (E))
8428 and then (not In_Instance
8429 or else No (Parent (E))
8430 or else Nkind (Unit_Declaration_Node (E)) /=
8431 N_Subprogram_Renaming_Declaration)
8433 -- A subprogram child unit is not allowed to override an
8434 -- inherited subprogram (10.1.1(20)).
8436 if Is_Child_Unit (S) then
8438 ("child unit overrides inherited subprogram in parent",
8443 if Is_Non_Overriding_Operation (E, S) then
8444 Enter_Overloaded_Entity (S);
8446 if No (Derived_Type)
8447 or else Is_Tagged_Type (Derived_Type)
8449 Check_Dispatching_Operation (S, Empty);
8455 -- E is a derived operation or an internal operator which
8456 -- is being overridden. Remove E from further visibility.
8457 -- Furthermore, if E is a dispatching operation, it must be
8458 -- replaced in the list of primitive operations of its type
8459 -- (see Override_Dispatching_Operation).
8461 Overridden_Subp := E;
8467 Prev := First_Entity (Current_Scope);
8468 while Present (Prev)
8469 and then Next_Entity (Prev) /= E
8474 -- It is possible for E to be in the current scope and
8475 -- yet not in the entity chain. This can only occur in a
8476 -- generic context where E is an implicit concatenation
8477 -- in the formal part, because in a generic body the
8478 -- entity chain starts with the formals.
8481 (Present (Prev) or else Chars (E) = Name_Op_Concat);
8483 -- E must be removed both from the entity_list of the
8484 -- current scope, and from the visibility chain
8486 if Debug_Flag_E then
8487 Write_Str ("Override implicit operation ");
8488 Write_Int (Int (E));
8492 -- If E is a predefined concatenation, it stands for four
8493 -- different operations. As a result, a single explicit
8494 -- declaration does not hide it. In a possible ambiguous
8495 -- situation, Disambiguate chooses the user-defined op,
8496 -- so it is correct to retain the previous internal one.
8498 if Chars (E) /= Name_Op_Concat
8499 or else Ekind (E) /= E_Operator
8501 -- For nondispatching derived operations that are
8502 -- overridden by a subprogram declared in the private
8503 -- part of a package, we retain the derived subprogram
8504 -- but mark it as not immediately visible. If the
8505 -- derived operation was declared in the visible part
8506 -- then this ensures that it will still be visible
8507 -- outside the package with the proper signature
8508 -- (calls from outside must also be directed to this
8509 -- version rather than the overriding one, unlike the
8510 -- dispatching case). Calls from inside the package
8511 -- will still resolve to the overriding subprogram
8512 -- since the derived one is marked as not visible
8513 -- within the package.
8515 -- If the private operation is dispatching, we achieve
8516 -- the overriding by keeping the implicit operation
8517 -- but setting its alias to be the overriding one. In
8518 -- this fashion the proper body is executed in all
8519 -- cases, but the original signature is used outside
8522 -- If the overriding is not in the private part, we
8523 -- remove the implicit operation altogether.
8525 if Is_Private_Declaration (S) then
8526 if not Is_Dispatching_Operation (E) then
8527 Set_Is_Immediately_Visible (E, False);
8529 -- Work done in Override_Dispatching_Operation,
8530 -- so nothing else need to be done here.
8536 -- Find predecessor of E in Homonym chain
8538 if E = Current_Entity (E) then
8541 Prev_Vis := Current_Entity (E);
8542 while Homonym (Prev_Vis) /= E loop
8543 Prev_Vis := Homonym (Prev_Vis);
8547 if Prev_Vis /= Empty then
8549 -- Skip E in the visibility chain
8551 Set_Homonym (Prev_Vis, Homonym (E));
8554 Set_Name_Entity_Id (Chars (E), Homonym (E));
8557 Set_Next_Entity (Prev, Next_Entity (E));
8559 if No (Next_Entity (Prev)) then
8560 Set_Last_Entity (Current_Scope, Prev);
8565 Enter_Overloaded_Entity (S);
8567 -- For entities generated by Derive_Subprograms the
8568 -- overridden operation is the inherited primitive
8569 -- (which is available through the attribute alias).
8571 if not (Comes_From_Source (E))
8572 and then Is_Dispatching_Operation (E)
8573 and then Find_Dispatching_Type (E) =
8574 Find_Dispatching_Type (S)
8575 and then Present (Alias (E))
8576 and then Comes_From_Source (Alias (E))
8578 Set_Overridden_Operation (S, Alias (E));
8580 -- Normal case of setting entity as overridden
8582 -- Note: Static_Initialization and Overridden_Operation
8583 -- attributes use the same field in subprogram entities.
8584 -- Static_Initialization is only defined for internal
8585 -- initialization procedures, where Overridden_Operation
8586 -- is irrelevant. Therefore the setting of this attribute
8587 -- must check whether the target is an init_proc.
8589 elsif not Is_Init_Proc (S) then
8590 Set_Overridden_Operation (S, E);
8593 Check_Overriding_Indicator (S, E, Is_Primitive => True);
8595 -- If S is a user-defined subprogram or a null procedure
8596 -- expanded to override an inherited null procedure, or a
8597 -- predefined dispatching primitive then indicate that E
8598 -- overrides the operation from which S is inherited.
8600 if Comes_From_Source (S)
8602 (Present (Parent (S))
8604 Nkind (Parent (S)) = N_Procedure_Specification
8606 Null_Present (Parent (S)))
8608 (Present (Alias (E))
8610 Is_Predefined_Dispatching_Operation (Alias (E)))
8612 if Present (Alias (E)) then
8613 Set_Overridden_Operation (S, Alias (E));
8617 if Is_Dispatching_Operation (E) then
8619 -- An overriding dispatching subprogram inherits the
8620 -- convention of the overridden subprogram (AI-117).
8622 Set_Convention (S, Convention (E));
8623 Check_Dispatching_Operation (S, E);
8626 Check_Dispatching_Operation (S, Empty);
8629 Check_For_Primitive_Subprogram
8630 (Is_Primitive_Subp, Is_Overriding => True);
8631 goto Check_Inequality;
8634 -- Apparent redeclarations in instances can occur when two
8635 -- formal types get the same actual type. The subprograms in
8636 -- in the instance are legal, even if not callable from the
8637 -- outside. Calls from within are disambiguated elsewhere.
8638 -- For dispatching operations in the visible part, the usual
8639 -- rules apply, and operations with the same profile are not
8642 elsif (In_Instance_Visible_Part
8643 and then not Is_Dispatching_Operation (E))
8644 or else In_Instance_Not_Visible
8648 -- Here we have a real error (identical profile)
8651 Error_Msg_Sloc := Sloc (E);
8653 -- Avoid cascaded errors if the entity appears in
8654 -- subsequent calls.
8656 Set_Scope (S, Current_Scope);
8658 -- Generate error, with extra useful warning for the case
8659 -- of a generic instance with no completion.
8661 if Is_Generic_Instance (S)
8662 and then not Has_Completion (E)
8665 ("instantiation cannot provide body for&", S);
8666 Error_Msg_N ("\& conflicts with declaration#", S);
8668 Error_Msg_N ("& conflicts with declaration#", S);
8675 -- If one subprogram has an access parameter and the other
8676 -- a parameter of an access type, calls to either might be
8677 -- ambiguous. Verify that parameters match except for the
8678 -- access parameter.
8680 if May_Hide_Profile then
8686 F1 := First_Formal (S);
8687 F2 := First_Formal (E);
8688 while Present (F1) and then Present (F2) loop
8689 if Is_Access_Type (Etype (F1)) then
8690 if not Is_Access_Type (Etype (F2))
8691 or else not Conforming_Types
8692 (Designated_Type (Etype (F1)),
8693 Designated_Type (Etype (F2)),
8696 May_Hide_Profile := False;
8700 not Conforming_Types
8701 (Etype (F1), Etype (F2), Type_Conformant)
8703 May_Hide_Profile := False;
8714 Error_Msg_NE ("calls to& may be ambiguous?", S, S);
8723 -- On exit, we know that S is a new entity
8725 Enter_Overloaded_Entity (S);
8726 Check_For_Primitive_Subprogram (Is_Primitive_Subp);
8727 Check_Overriding_Indicator
8728 (S, Overridden_Subp, Is_Primitive => Is_Primitive_Subp);
8730 -- Overloading is not allowed in SPARK, except for operators
8732 if Nkind (S) /= N_Defining_Operator_Symbol then
8733 Error_Msg_Sloc := Sloc (Homonym (S));
8734 Check_SPARK_Restriction
8735 ("overloading not allowed with entity#", S);
8738 -- If S is a derived operation for an untagged type then by
8739 -- definition it's not a dispatching operation (even if the parent
8740 -- operation was dispatching), so Check_Dispatching_Operation is not
8741 -- called in that case.
8743 if No (Derived_Type)
8744 or else Is_Tagged_Type (Derived_Type)
8746 Check_Dispatching_Operation (S, Empty);
8750 -- If this is a user-defined equality operator that is not a derived
8751 -- subprogram, create the corresponding inequality. If the operation is
8752 -- dispatching, the expansion is done elsewhere, and we do not create
8753 -- an explicit inequality operation.
8755 <<Check_Inequality>>
8756 if Chars (S) = Name_Op_Eq
8757 and then Etype (S) = Standard_Boolean
8758 and then Present (Parent (S))
8759 and then not Is_Dispatching_Operation (S)
8761 Make_Inequality_Operator (S);
8763 if Ada_Version >= Ada_2012 then
8764 Check_Untagged_Equality (S);
8767 end New_Overloaded_Entity;
8769 ---------------------
8770 -- Process_Formals --
8771 ---------------------
8773 procedure Process_Formals
8775 Related_Nod : Node_Id)
8777 Param_Spec : Node_Id;
8779 Formal_Type : Entity_Id;
8783 Num_Out_Params : Nat := 0;
8784 First_Out_Param : Entity_Id := Empty;
8785 -- Used for setting Is_Only_Out_Parameter
8787 function Designates_From_With_Type (Typ : Entity_Id) return Boolean;
8788 -- Determine whether an access type designates a type coming from a
8791 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
8792 -- Check whether the default has a class-wide type. After analysis the
8793 -- default has the type of the formal, so we must also check explicitly
8794 -- for an access attribute.
8796 -------------------------------
8797 -- Designates_From_With_Type --
8798 -------------------------------
8800 function Designates_From_With_Type (Typ : Entity_Id) return Boolean is
8801 Desig : Entity_Id := Typ;
8804 if Is_Access_Type (Desig) then
8805 Desig := Directly_Designated_Type (Desig);
8808 if Is_Class_Wide_Type (Desig) then
8809 Desig := Root_Type (Desig);
8813 Ekind (Desig) = E_Incomplete_Type
8814 and then From_With_Type (Desig);
8815 end Designates_From_With_Type;
8817 ---------------------------
8818 -- Is_Class_Wide_Default --
8819 ---------------------------
8821 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
8823 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
8824 or else (Nkind (D) = N_Attribute_Reference
8825 and then Attribute_Name (D) = Name_Access
8826 and then Is_Class_Wide_Type (Etype (Prefix (D))));
8827 end Is_Class_Wide_Default;
8829 -- Start of processing for Process_Formals
8832 -- In order to prevent premature use of the formals in the same formal
8833 -- part, the Ekind is left undefined until all default expressions are
8834 -- analyzed. The Ekind is established in a separate loop at the end.
8836 Param_Spec := First (T);
8837 while Present (Param_Spec) loop
8838 Formal := Defining_Identifier (Param_Spec);
8839 Set_Never_Set_In_Source (Formal, True);
8840 Enter_Name (Formal);
8842 -- Case of ordinary parameters
8844 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
8845 Find_Type (Parameter_Type (Param_Spec));
8846 Ptype := Parameter_Type (Param_Spec);
8848 if Ptype = Error then
8852 Formal_Type := Entity (Ptype);
8854 if Is_Incomplete_Type (Formal_Type)
8856 (Is_Class_Wide_Type (Formal_Type)
8857 and then Is_Incomplete_Type (Root_Type (Formal_Type)))
8859 -- Ada 2005 (AI-326): Tagged incomplete types allowed in
8860 -- primitive operations, as long as their completion is
8861 -- in the same declarative part. If in the private part
8862 -- this means that the type cannot be a Taft-amendment type.
8863 -- Check is done on package exit. For access to subprograms,
8864 -- the use is legal for Taft-amendment types.
8866 if Is_Tagged_Type (Formal_Type) then
8867 if Ekind (Scope (Current_Scope)) = E_Package
8868 and then not From_With_Type (Formal_Type)
8869 and then not Is_Class_Wide_Type (Formal_Type)
8872 (Parent (T), N_Access_Function_Definition,
8873 N_Access_Procedure_Definition)
8877 Private_Dependents (Base_Type (Formal_Type)));
8879 -- Freezing is delayed to ensure that Register_Prim
8880 -- will get called for this operation, which is needed
8881 -- in cases where static dispatch tables aren't built.
8882 -- (Note that the same is done for controlling access
8883 -- parameter cases in function Access_Definition.)
8885 Set_Has_Delayed_Freeze (Current_Scope);
8889 -- Special handling of Value_Type for CIL case
8891 elsif Is_Value_Type (Formal_Type) then
8894 elsif not Nkind_In (Parent (T), N_Access_Function_Definition,
8895 N_Access_Procedure_Definition)
8898 -- AI05-0151: Tagged incomplete types are allowed in all
8899 -- formal parts. Untagged incomplete types are not allowed
8902 if Ada_Version >= Ada_2012 then
8903 if Is_Tagged_Type (Formal_Type) then
8906 elsif Nkind_In (Parent (Parent (T)), N_Accept_Statement,
8911 ("invalid use of untagged incomplete type&",
8912 Ptype, Formal_Type);
8917 ("invalid use of incomplete type&",
8918 Param_Spec, Formal_Type);
8920 -- Further checks on the legality of incomplete types
8921 -- in formal parts are delayed until the freeze point
8922 -- of the enclosing subprogram or access to subprogram.
8926 elsif Ekind (Formal_Type) = E_Void then
8928 ("premature use of&",
8929 Parameter_Type (Param_Spec), Formal_Type);
8932 -- Ada 2005 (AI-231): Create and decorate an internal subtype
8933 -- declaration corresponding to the null-excluding type of the
8934 -- formal in the enclosing scope. Finally, replace the parameter
8935 -- type of the formal with the internal subtype.
8937 if Ada_Version >= Ada_2005
8938 and then Null_Exclusion_Present (Param_Spec)
8940 if not Is_Access_Type (Formal_Type) then
8942 ("`NOT NULL` allowed only for an access type", Param_Spec);
8945 if Can_Never_Be_Null (Formal_Type)
8946 and then Comes_From_Source (Related_Nod)
8949 ("`NOT NULL` not allowed (& already excludes null)",
8950 Param_Spec, Formal_Type);
8954 Create_Null_Excluding_Itype
8956 Related_Nod => Related_Nod,
8957 Scope_Id => Scope (Current_Scope));
8959 -- If the designated type of the itype is an itype we
8960 -- decorate it with the Has_Delayed_Freeze attribute to
8961 -- avoid problems with the backend.
8964 -- type T is access procedure;
8965 -- procedure Op (O : not null T);
8967 if Is_Itype (Directly_Designated_Type (Formal_Type)) then
8968 Set_Has_Delayed_Freeze (Formal_Type);
8973 -- An access formal type
8977 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
8979 -- No need to continue if we already notified errors
8981 if not Present (Formal_Type) then
8985 -- Ada 2005 (AI-254)
8988 AD : constant Node_Id :=
8989 Access_To_Subprogram_Definition
8990 (Parameter_Type (Param_Spec));
8992 if Present (AD) and then Protected_Present (AD) then
8994 Replace_Anonymous_Access_To_Protected_Subprogram
9000 Set_Etype (Formal, Formal_Type);
9002 Default := Expression (Param_Spec);
9004 if Present (Default) then
9005 Check_SPARK_Restriction
9006 ("default expression is not allowed", Default);
9008 if Out_Present (Param_Spec) then
9010 ("default initialization only allowed for IN parameters",
9014 -- Do the special preanalysis of the expression (see section on
9015 -- "Handling of Default Expressions" in the spec of package Sem).
9017 Preanalyze_Spec_Expression (Default, Formal_Type);
9019 -- An access to constant cannot be the default for
9020 -- an access parameter that is an access to variable.
9022 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9023 and then not Is_Access_Constant (Formal_Type)
9024 and then Is_Access_Type (Etype (Default))
9025 and then Is_Access_Constant (Etype (Default))
9028 ("formal that is access to variable cannot be initialized " &
9029 "with an access-to-constant expression", Default);
9032 -- Check that the designated type of an access parameter's default
9033 -- is not a class-wide type unless the parameter's designated type
9034 -- is also class-wide.
9036 if Ekind (Formal_Type) = E_Anonymous_Access_Type
9037 and then not Designates_From_With_Type (Formal_Type)
9038 and then Is_Class_Wide_Default (Default)
9039 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
9042 ("access to class-wide expression not allowed here", Default);
9045 -- Check incorrect use of dynamically tagged expressions
9047 if Is_Tagged_Type (Formal_Type) then
9048 Check_Dynamically_Tagged_Expression
9051 Related_Nod => Default);
9055 -- Ada 2005 (AI-231): Static checks
9057 if Ada_Version >= Ada_2005
9058 and then Is_Access_Type (Etype (Formal))
9059 and then Can_Never_Be_Null (Etype (Formal))
9061 Null_Exclusion_Static_Checks (Param_Spec);
9068 -- If this is the formal part of a function specification, analyze the
9069 -- subtype mark in the context where the formals are visible but not
9070 -- yet usable, and may hide outer homographs.
9072 if Nkind (Related_Nod) = N_Function_Specification then
9073 Analyze_Return_Type (Related_Nod);
9076 -- Now set the kind (mode) of each formal
9078 Param_Spec := First (T);
9079 while Present (Param_Spec) loop
9080 Formal := Defining_Identifier (Param_Spec);
9081 Set_Formal_Mode (Formal);
9083 if Ekind (Formal) = E_In_Parameter then
9084 Set_Default_Value (Formal, Expression (Param_Spec));
9086 if Present (Expression (Param_Spec)) then
9087 Default := Expression (Param_Spec);
9089 if Is_Scalar_Type (Etype (Default)) then
9091 (Parameter_Type (Param_Spec)) /= N_Access_Definition
9093 Formal_Type := Entity (Parameter_Type (Param_Spec));
9096 Formal_Type := Access_Definition
9097 (Related_Nod, Parameter_Type (Param_Spec));
9100 Apply_Scalar_Range_Check (Default, Formal_Type);
9104 elsif Ekind (Formal) = E_Out_Parameter then
9105 Num_Out_Params := Num_Out_Params + 1;
9107 if Num_Out_Params = 1 then
9108 First_Out_Param := Formal;
9111 elsif Ekind (Formal) = E_In_Out_Parameter then
9112 Num_Out_Params := Num_Out_Params + 1;
9118 if Present (First_Out_Param) and then Num_Out_Params = 1 then
9119 Set_Is_Only_Out_Parameter (First_Out_Param);
9121 end Process_Formals;
9127 procedure Process_PPCs
9129 Spec_Id : Entity_Id;
9130 Body_Id : Entity_Id)
9132 Loc : constant Source_Ptr := Sloc (N);
9136 Designator : Entity_Id;
9137 -- Subprogram designator, set from Spec_Id if present, else Body_Id
9139 Precond : Node_Id := Empty;
9140 -- Set non-Empty if we prepend precondition to the declarations. This
9141 -- is used to hook up inherited preconditions (adding the condition
9142 -- expression with OR ELSE, and adding the message).
9144 Inherited_Precond : Node_Id;
9145 -- Precondition inherited from parent subprogram
9147 Inherited : constant Subprogram_List :=
9148 Inherited_Subprograms (Spec_Id);
9149 -- List of subprograms inherited by this subprogram
9151 Plist : List_Id := No_List;
9152 -- List of generated postconditions
9154 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id;
9155 -- Prag contains an analyzed precondition or postcondition pragma. This
9156 -- function copies the pragma, changes it to the corresponding Check
9157 -- pragma and returns the Check pragma as the result. If Pspec is non-
9158 -- empty, this is the case of inheriting a PPC, where we must change
9159 -- references to parameters of the inherited subprogram to point to the
9160 -- corresponding parameters of the current subprogram.
9162 function Invariants_Or_Predicates_Present return Boolean;
9163 -- Determines if any invariants or predicates are present for any OUT
9164 -- or IN OUT parameters of the subprogram, or (for a function) if the
9165 -- return value has an invariant.
9171 function Grab_PPC (Pspec : Entity_Id := Empty) return Node_Id is
9172 Nam : constant Name_Id := Pragma_Name (Prag);
9177 -- Prepare map if this is the case where we have to map entities of
9178 -- arguments in the overridden subprogram to corresponding entities
9179 -- of the current subprogram.
9190 Map := New_Elmt_List;
9191 PF := First_Formal (Pspec);
9192 CF := First_Formal (Designator);
9193 while Present (PF) loop
9194 Append_Elmt (PF, Map);
9195 Append_Elmt (CF, Map);
9202 -- Now we can copy the tree, doing any required substitutions
9204 CP := New_Copy_Tree (Prag, Map => Map, New_Scope => Current_Scope);
9206 -- Set Analyzed to false, since we want to reanalyze the check
9207 -- procedure. Note that it is only at the outer level that we
9208 -- do this fiddling, for the spec cases, the already preanalyzed
9209 -- parameters are not affected.
9211 Set_Analyzed (CP, False);
9213 -- We also make sure Comes_From_Source is False for the copy
9215 Set_Comes_From_Source (CP, False);
9217 -- For a postcondition pragma within a generic, preserve the pragma
9218 -- for later expansion.
9220 if Nam = Name_Postcondition
9221 and then not Expander_Active
9226 -- Change copy of pragma into corresponding pragma Check
9228 Prepend_To (Pragma_Argument_Associations (CP),
9229 Make_Pragma_Argument_Association (Sloc (Prag),
9230 Expression => Make_Identifier (Loc, Nam)));
9231 Set_Pragma_Identifier (CP, Make_Identifier (Sloc (Prag), Name_Check));
9233 -- If this is inherited case and the current message starts with
9234 -- "failed p", we change it to "failed inherited p...".
9236 if Present (Pspec) then
9238 Msg : constant Node_Id :=
9239 Last (Pragma_Argument_Associations (CP));
9242 if Chars (Msg) = Name_Message then
9243 String_To_Name_Buffer (Strval (Expression (Msg)));
9245 if Name_Buffer (1 .. 8) = "failed p" then
9246 Insert_Str_In_Name_Buffer ("inherited ", 8);
9248 (Expression (Last (Pragma_Argument_Associations (CP))),
9249 String_From_Name_Buffer);
9255 -- Return the check pragma
9260 --------------------------------------
9261 -- Invariants_Or_Predicates_Present --
9262 --------------------------------------
9264 function Invariants_Or_Predicates_Present return Boolean is
9268 -- Check function return result
9270 if Ekind (Designator) /= E_Procedure
9271 and then Has_Invariants (Etype (Designator))
9278 Formal := First_Formal (Designator);
9279 while Present (Formal) loop
9280 if Ekind (Formal) /= E_In_Parameter
9282 (Has_Invariants (Etype (Formal))
9283 or else Present (Predicate_Function (Etype (Formal))))
9288 Next_Formal (Formal);
9292 end Invariants_Or_Predicates_Present;
9294 -- Start of processing for Process_PPCs
9297 -- Capture designator from spec if present, else from body
9299 if Present (Spec_Id) then
9300 Designator := Spec_Id;
9302 Designator := Body_Id;
9305 -- Grab preconditions from spec
9307 if Present (Spec_Id) then
9309 -- Loop through PPC pragmas from spec. Note that preconditions from
9310 -- the body will be analyzed and converted when we scan the body
9311 -- declarations below.
9313 Prag := Spec_PPC_List (Contract (Spec_Id));
9314 while Present (Prag) loop
9315 if Pragma_Name (Prag) = Name_Precondition then
9317 -- For Pre (or Precondition pragma), we simply prepend the
9318 -- pragma to the list of declarations right away so that it
9319 -- will be executed at the start of the procedure. Note that
9320 -- this processing reverses the order of the list, which is
9321 -- what we want since new entries were chained to the head of
9322 -- the list. There can be more than one precondition when we
9323 -- use pragma Precondition.
9325 if not Class_Present (Prag) then
9326 Prepend (Grab_PPC, Declarations (N));
9328 -- For Pre'Class there can only be one pragma, and we save
9329 -- it in Precond for now. We will add inherited Pre'Class
9330 -- stuff before inserting this pragma in the declarations.
9332 Precond := Grab_PPC;
9336 Prag := Next_Pragma (Prag);
9339 -- Now deal with inherited preconditions
9341 for J in Inherited'Range loop
9342 Prag := Spec_PPC_List (Contract (Inherited (J)));
9344 while Present (Prag) loop
9345 if Pragma_Name (Prag) = Name_Precondition
9346 and then Class_Present (Prag)
9348 Inherited_Precond := Grab_PPC (Inherited (J));
9350 -- No precondition so far, so establish this as the first
9352 if No (Precond) then
9353 Precond := Inherited_Precond;
9355 -- Here we already have a precondition, add inherited one
9358 -- Add new precondition to old one using OR ELSE
9361 New_Expr : constant Node_Id :=
9365 (Pragma_Argument_Associations
9366 (Inherited_Precond))));
9367 Old_Expr : constant Node_Id :=
9371 (Pragma_Argument_Associations
9375 if Paren_Count (Old_Expr) = 0 then
9376 Set_Paren_Count (Old_Expr, 1);
9379 if Paren_Count (New_Expr) = 0 then
9380 Set_Paren_Count (New_Expr, 1);
9384 Make_Or_Else (Sloc (Old_Expr),
9385 Left_Opnd => Relocate_Node (Old_Expr),
9386 Right_Opnd => New_Expr));
9389 -- Add new message in the form:
9391 -- failed precondition from bla
9392 -- also failed inherited precondition from bla
9395 -- Skip this if exception locations are suppressed
9397 if not Exception_Locations_Suppressed then
9399 New_Msg : constant Node_Id :=
9402 (Pragma_Argument_Associations
9403 (Inherited_Precond)));
9404 Old_Msg : constant Node_Id :=
9407 (Pragma_Argument_Associations
9410 Start_String (Strval (Old_Msg));
9411 Store_String_Chars (ASCII.LF & " also ");
9412 Store_String_Chars (Strval (New_Msg));
9413 Set_Strval (Old_Msg, End_String);
9419 Prag := Next_Pragma (Prag);
9423 -- If we have built a precondition for Pre'Class (including any
9424 -- Pre'Class aspects inherited from parent subprograms), then we
9425 -- insert this composite precondition at this stage.
9427 if Present (Precond) then
9428 Prepend (Precond, Declarations (N));
9432 -- Build postconditions procedure if needed and prepend the following
9433 -- declaration to the start of the declarations for the subprogram.
9435 -- procedure _postconditions [(_Result : resulttype)] is
9437 -- pragma Check (Postcondition, condition [,message]);
9438 -- pragma Check (Postcondition, condition [,message]);
9440 -- Invariant_Procedure (_Result) ...
9441 -- Invariant_Procedure (Arg1)
9445 -- First we deal with the postconditions in the body
9447 if Is_Non_Empty_List (Declarations (N)) then
9449 -- Loop through declarations
9451 Prag := First (Declarations (N));
9452 while Present (Prag) loop
9453 if Nkind (Prag) = N_Pragma then
9455 -- If pragma, capture if enabled postcondition, else ignore
9457 if Pragma_Name (Prag) = Name_Postcondition
9458 and then Check_Enabled (Name_Postcondition)
9460 if Plist = No_List then
9461 Plist := Empty_List;
9466 -- If expansion is disabled, as in a generic unit, save
9467 -- pragma for later expansion.
9469 if not Expander_Active then
9470 Prepend (Grab_PPC, Declarations (N));
9472 Append (Grab_PPC, Plist);
9478 -- Not a pragma, if comes from source, then end scan
9480 elsif Comes_From_Source (Prag) then
9483 -- Skip stuff not coming from source
9491 -- Now deal with any postconditions from the spec
9493 if Present (Spec_Id) then
9494 Spec_Postconditions : declare
9495 procedure Process_Post_Conditions
9498 -- This processes the Spec_PPC_List from Spec, processing any
9499 -- postconditions from the list. If Class is True, then only
9500 -- postconditions marked with Class_Present are considered.
9501 -- The caller has checked that Spec_PPC_List is non-Empty.
9503 -----------------------------
9504 -- Process_Post_Conditions --
9505 -----------------------------
9507 procedure Process_Post_Conditions
9520 -- Loop through PPC pragmas from spec
9522 Prag := Spec_PPC_List (Contract (Spec));
9524 if Pragma_Name (Prag) = Name_Postcondition
9525 and then (not Class or else Class_Present (Prag))
9527 if Plist = No_List then
9528 Plist := Empty_List;
9531 if not Expander_Active then
9533 (Grab_PPC (Pspec), Declarations (N));
9535 Append (Grab_PPC (Pspec), Plist);
9539 Prag := Next_Pragma (Prag);
9540 exit when No (Prag);
9542 end Process_Post_Conditions;
9544 -- Start of processing for Spec_Postconditions
9547 if Present (Spec_PPC_List (Contract (Spec_Id))) then
9548 Process_Post_Conditions (Spec_Id, Class => False);
9551 -- Process inherited postconditions
9553 for J in Inherited'Range loop
9554 if Present (Spec_PPC_List (Contract (Inherited (J)))) then
9555 Process_Post_Conditions (Inherited (J), Class => True);
9558 end Spec_Postconditions;
9561 -- If we had any postconditions and expansion is enabled, or if the
9562 -- procedure has invariants, then build the _Postconditions procedure.
9564 if (Present (Plist) or else Invariants_Or_Predicates_Present)
9565 and then Expander_Active
9568 Plist := Empty_List;
9571 -- Special processing for function case
9573 if Ekind (Designator) /= E_Procedure then
9575 Rent : constant Entity_Id :=
9576 Make_Defining_Identifier (Loc,
9577 Chars => Name_uResult);
9578 Ftyp : constant Entity_Id := Etype (Designator);
9581 Set_Etype (Rent, Ftyp);
9583 -- Add argument for return
9587 Make_Parameter_Specification (Loc,
9588 Parameter_Type => New_Occurrence_Of (Ftyp, Loc),
9589 Defining_Identifier => Rent));
9591 -- Add invariant call if returning type with invariants
9593 if Has_Invariants (Etype (Rent))
9594 and then Present (Invariant_Procedure (Etype (Rent)))
9597 Make_Invariant_Call (New_Occurrence_Of (Rent, Loc)));
9601 -- Procedure rather than a function
9607 -- Add invariant calls and predicate calls for parameters. Note that
9608 -- this is done for functions as well, since in Ada 2012 they can
9609 -- have IN OUT args.
9616 Formal := First_Formal (Designator);
9617 while Present (Formal) loop
9618 if Ekind (Formal) /= E_In_Parameter then
9619 Ftype := Etype (Formal);
9621 if Has_Invariants (Ftype)
9622 and then Present (Invariant_Procedure (Ftype))
9626 (New_Occurrence_Of (Formal, Loc)));
9629 if Present (Predicate_Function (Ftype)) then
9631 Make_Predicate_Check
9632 (Ftype, New_Occurrence_Of (Formal, Loc)));
9636 Next_Formal (Formal);
9640 -- Build and insert postcondition procedure
9643 Post_Proc : constant Entity_Id :=
9644 Make_Defining_Identifier (Loc,
9645 Chars => Name_uPostconditions);
9646 -- The entity for the _Postconditions procedure
9649 Prepend_To (Declarations (N),
9650 Make_Subprogram_Body (Loc,
9652 Make_Procedure_Specification (Loc,
9653 Defining_Unit_Name => Post_Proc,
9654 Parameter_Specifications => Parms),
9656 Declarations => Empty_List,
9658 Handled_Statement_Sequence =>
9659 Make_Handled_Sequence_Of_Statements (Loc,
9660 Statements => Plist)));
9662 Set_Ekind (Post_Proc, E_Procedure);
9664 -- If this is a procedure, set the Postcondition_Proc attribute on
9665 -- the proper defining entity for the subprogram.
9667 if Ekind (Designator) = E_Procedure then
9668 Set_Postcondition_Proc (Designator, Post_Proc);
9672 Set_Has_Postconditions (Designator);
9676 ----------------------------
9677 -- Reference_Body_Formals --
9678 ----------------------------
9680 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id) is
9685 if Error_Posted (Spec) then
9689 -- Iterate over both lists. They may be of different lengths if the two
9690 -- specs are not conformant.
9692 Fs := First_Formal (Spec);
9693 Fb := First_Formal (Bod);
9694 while Present (Fs) and then Present (Fb) loop
9695 Generate_Reference (Fs, Fb, 'b');
9698 Style.Check_Identifier (Fb, Fs);
9701 Set_Spec_Entity (Fb, Fs);
9702 Set_Referenced (Fs, False);
9706 end Reference_Body_Formals;
9708 -------------------------
9709 -- Set_Actual_Subtypes --
9710 -------------------------
9712 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
9716 First_Stmt : Node_Id := Empty;
9717 AS_Needed : Boolean;
9720 -- If this is an empty initialization procedure, no need to create
9721 -- actual subtypes (small optimization).
9723 if Ekind (Subp) = E_Procedure
9724 and then Is_Null_Init_Proc (Subp)
9729 Formal := First_Formal (Subp);
9730 while Present (Formal) loop
9731 T := Etype (Formal);
9733 -- We never need an actual subtype for a constrained formal
9735 if Is_Constrained (T) then
9738 -- If we have unknown discriminants, then we do not need an actual
9739 -- subtype, or more accurately we cannot figure it out! Note that
9740 -- all class-wide types have unknown discriminants.
9742 elsif Has_Unknown_Discriminants (T) then
9745 -- At this stage we have an unconstrained type that may need an
9746 -- actual subtype. For sure the actual subtype is needed if we have
9747 -- an unconstrained array type.
9749 elsif Is_Array_Type (T) then
9752 -- The only other case needing an actual subtype is an unconstrained
9753 -- record type which is an IN parameter (we cannot generate actual
9754 -- subtypes for the OUT or IN OUT case, since an assignment can
9755 -- change the discriminant values. However we exclude the case of
9756 -- initialization procedures, since discriminants are handled very
9757 -- specially in this context, see the section entitled "Handling of
9758 -- Discriminants" in Einfo.
9760 -- We also exclude the case of Discrim_SO_Functions (functions used
9761 -- in front end layout mode for size/offset values), since in such
9762 -- functions only discriminants are referenced, and not only are such
9763 -- subtypes not needed, but they cannot always be generated, because
9764 -- of order of elaboration issues.
9766 elsif Is_Record_Type (T)
9767 and then Ekind (Formal) = E_In_Parameter
9768 and then Chars (Formal) /= Name_uInit
9769 and then not Is_Unchecked_Union (T)
9770 and then not Is_Discrim_SO_Function (Subp)
9774 -- All other cases do not need an actual subtype
9780 -- Generate actual subtypes for unconstrained arrays and
9781 -- unconstrained discriminated records.
9784 if Nkind (N) = N_Accept_Statement then
9786 -- If expansion is active, the formal is replaced by a local
9787 -- variable that renames the corresponding entry of the
9788 -- parameter block, and it is this local variable that may
9789 -- require an actual subtype.
9791 if Full_Expander_Active then
9792 Decl := Build_Actual_Subtype (T, Renamed_Object (Formal));
9794 Decl := Build_Actual_Subtype (T, Formal);
9797 if Present (Handled_Statement_Sequence (N)) then
9799 First (Statements (Handled_Statement_Sequence (N)));
9800 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
9801 Mark_Rewrite_Insertion (Decl);
9803 -- If the accept statement has no body, there will be no
9804 -- reference to the actuals, so no need to compute actual
9811 Decl := Build_Actual_Subtype (T, Formal);
9812 Prepend (Decl, Declarations (N));
9813 Mark_Rewrite_Insertion (Decl);
9816 -- The declaration uses the bounds of an existing object, and
9817 -- therefore needs no constraint checks.
9819 Analyze (Decl, Suppress => All_Checks);
9821 -- We need to freeze manually the generated type when it is
9822 -- inserted anywhere else than in a declarative part.
9824 if Present (First_Stmt) then
9825 Insert_List_Before_And_Analyze (First_Stmt,
9826 Freeze_Entity (Defining_Identifier (Decl), N));
9829 if Nkind (N) = N_Accept_Statement
9830 and then Full_Expander_Active
9832 Set_Actual_Subtype (Renamed_Object (Formal),
9833 Defining_Identifier (Decl));
9835 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
9839 Next_Formal (Formal);
9841 end Set_Actual_Subtypes;
9843 ---------------------
9844 -- Set_Formal_Mode --
9845 ---------------------
9847 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
9848 Spec : constant Node_Id := Parent (Formal_Id);
9851 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
9852 -- since we ensure that corresponding actuals are always valid at the
9853 -- point of the call.
9855 if Out_Present (Spec) then
9856 if Ekind (Scope (Formal_Id)) = E_Function
9857 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
9859 -- [IN] OUT parameters allowed for functions in Ada 2012
9861 if Ada_Version >= Ada_2012 then
9862 if In_Present (Spec) then
9863 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9865 Set_Ekind (Formal_Id, E_Out_Parameter);
9868 -- But not in earlier versions of Ada
9871 Error_Msg_N ("functions can only have IN parameters", Spec);
9872 Set_Ekind (Formal_Id, E_In_Parameter);
9875 elsif In_Present (Spec) then
9876 Set_Ekind (Formal_Id, E_In_Out_Parameter);
9879 Set_Ekind (Formal_Id, E_Out_Parameter);
9880 Set_Never_Set_In_Source (Formal_Id, True);
9881 Set_Is_True_Constant (Formal_Id, False);
9882 Set_Current_Value (Formal_Id, Empty);
9886 Set_Ekind (Formal_Id, E_In_Parameter);
9889 -- Set Is_Known_Non_Null for access parameters since the language
9890 -- guarantees that access parameters are always non-null. We also set
9891 -- Can_Never_Be_Null, since there is no way to change the value.
9893 if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
9895 -- Ada 2005 (AI-231): In Ada95, access parameters are always non-
9896 -- null; In Ada 2005, only if then null_exclusion is explicit.
9898 if Ada_Version < Ada_2005
9899 or else Can_Never_Be_Null (Etype (Formal_Id))
9901 Set_Is_Known_Non_Null (Formal_Id);
9902 Set_Can_Never_Be_Null (Formal_Id);
9905 -- Ada 2005 (AI-231): Null-exclusion access subtype
9907 elsif Is_Access_Type (Etype (Formal_Id))
9908 and then Can_Never_Be_Null (Etype (Formal_Id))
9910 Set_Is_Known_Non_Null (Formal_Id);
9913 Set_Mechanism (Formal_Id, Default_Mechanism);
9914 Set_Formal_Validity (Formal_Id);
9915 end Set_Formal_Mode;
9917 -------------------------
9918 -- Set_Formal_Validity --
9919 -------------------------
9921 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
9923 -- If no validity checking, then we cannot assume anything about the
9924 -- validity of parameters, since we do not know there is any checking
9925 -- of the validity on the call side.
9927 if not Validity_Checks_On then
9930 -- If validity checking for parameters is enabled, this means we are
9931 -- not supposed to make any assumptions about argument values.
9933 elsif Validity_Check_Parameters then
9936 -- If we are checking in parameters, we will assume that the caller is
9937 -- also checking parameters, so we can assume the parameter is valid.
9939 elsif Ekind (Formal_Id) = E_In_Parameter
9940 and then Validity_Check_In_Params
9942 Set_Is_Known_Valid (Formal_Id, True);
9944 -- Similar treatment for IN OUT parameters
9946 elsif Ekind (Formal_Id) = E_In_Out_Parameter
9947 and then Validity_Check_In_Out_Params
9949 Set_Is_Known_Valid (Formal_Id, True);
9951 end Set_Formal_Validity;
9953 ------------------------
9954 -- Subtype_Conformant --
9955 ------------------------
9957 function Subtype_Conformant
9958 (New_Id : Entity_Id;
9960 Skip_Controlling_Formals : Boolean := False) return Boolean
9964 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result,
9965 Skip_Controlling_Formals => Skip_Controlling_Formals);
9967 end Subtype_Conformant;
9969 ---------------------
9970 -- Type_Conformant --
9971 ---------------------
9973 function Type_Conformant
9974 (New_Id : Entity_Id;
9976 Skip_Controlling_Formals : Boolean := False) return Boolean
9980 May_Hide_Profile := False;
9983 (New_Id, Old_Id, Type_Conformant, False, Result,
9984 Skip_Controlling_Formals => Skip_Controlling_Formals);
9986 end Type_Conformant;
9988 -------------------------------
9989 -- Valid_Operator_Definition --
9990 -------------------------------
9992 procedure Valid_Operator_Definition (Designator : Entity_Id) is
9995 Id : constant Name_Id := Chars (Designator);
9999 F := First_Formal (Designator);
10000 while Present (F) loop
10003 if Present (Default_Value (F)) then
10005 ("default values not allowed for operator parameters",
10012 -- Verify that user-defined operators have proper number of arguments
10013 -- First case of operators which can only be unary
10015 if Id = Name_Op_Not
10016 or else Id = Name_Op_Abs
10020 -- Case of operators which can be unary or binary
10022 elsif Id = Name_Op_Add
10023 or Id = Name_Op_Subtract
10025 N_OK := (N in 1 .. 2);
10027 -- All other operators can only be binary
10035 ("incorrect number of arguments for operator", Designator);
10039 and then Base_Type (Etype (Designator)) = Standard_Boolean
10040 and then not Is_Intrinsic_Subprogram (Designator)
10043 ("explicit definition of inequality not allowed", Designator);
10045 end Valid_Operator_Definition;
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