1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2013, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Debug; use Debug;
28 with Einfo; use Einfo;
29 with Elists; use Elists;
30 with Errout; use Errout;
31 with Exp_Disp; use Exp_Disp;
32 with Fname; use Fname;
34 with Namet; use Namet;
35 with Nlists; use Nlists;
38 with Sem_Attr; use Sem_Attr;
39 with Sem_Aux; use Sem_Aux;
40 with Sem_Dist; use Sem_Dist;
41 with Sem_Eval; use Sem_Eval;
42 with Sem_Util; use Sem_Util;
43 with Sinfo; use Sinfo;
44 with Snames; use Snames;
45 with Stand; use Stand;
47 package body Sem_Cat is
49 -----------------------
50 -- Local Subprograms --
51 -----------------------
53 procedure Check_Categorization_Dependencies
54 (Unit_Entity : Entity_Id;
55 Depended_Entity : Entity_Id;
57 Is_Subunit : Boolean);
58 -- This procedure checks that the categorization of a lib unit and that
59 -- of the depended unit satisfy dependency restrictions.
60 -- The depended_entity can be the entity in a with_clause item, in which
61 -- case Info_Node denotes that item. The depended_entity can also be the
62 -- parent unit of a child unit, in which case Info_Node is the declaration
63 -- of the child unit. The error message is posted on Info_Node, and is
64 -- specialized if Is_Subunit is true.
66 procedure Check_Non_Static_Default_Expr
69 -- Iterate through the component list of a record definition, check
70 -- that no component is declared with a nonstatic default value.
71 -- If a nonstatic default exists, report an error on Obj_Decl.
73 function Has_Read_Write_Attributes (E : Entity_Id) return Boolean;
74 -- Return True if entity has attribute definition clauses for Read and
75 -- Write attributes that are visible at some place.
77 function Is_Non_Remote_Access_Type (E : Entity_Id) return Boolean;
78 -- Returns true if the entity is a type whose full view is a non-remote
79 -- access type, for the purpose of enforcing E.2.2(8) rules.
81 function Has_Non_Remote_Access (Typ : Entity_Id) return Boolean;
82 -- Return true if Typ or the type of any of its subcomponents is a non
83 -- remote access type and doesn't have user-defined stream attributes.
85 function No_External_Streaming (E : Entity_Id) return Boolean;
86 -- Return True if the entity or one of its subcomponents does not support
87 -- external streaming.
89 function In_RCI_Declaration (N : Node_Id) return Boolean;
90 -- Determines if a declaration is within the visible part of a Remote
91 -- Call Interface compilation unit, for semantic checking purposes only
92 -- (returns false within an instance and within the package body).
94 function In_RT_Declaration return Boolean;
95 -- Determines if current scope is within the declaration of a Remote Types
96 -- unit, for semantic checking purposes.
98 function In_Shared_Passive_Unit return Boolean;
99 -- Determines if current scope is within a Shared Passive compilation unit
101 function Static_Discriminant_Expr (L : List_Id) return Boolean;
102 -- Iterate through the list of discriminants to check if any of them
103 -- contains non-static default expression, which is a violation in
104 -- a preelaborated library unit.
106 procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id);
107 -- Check validity of declaration if RCI or RT unit. It should not contain
108 -- the declaration of an access-to-object type unless it is a general
109 -- access type that designates a class-wide limited private type. There are
110 -- also constraints about the primitive subprograms of the class-wide type.
111 -- RM E.2 (9, 13, 14)
113 procedure Validate_RACW_Primitive
116 -- Check legality of the declaration of primitive Subp of the designated
117 -- type of the given RACW type.
119 ---------------------------------------
120 -- Check_Categorization_Dependencies --
121 ---------------------------------------
123 procedure Check_Categorization_Dependencies
124 (Unit_Entity : Entity_Id;
125 Depended_Entity : Entity_Id;
127 Is_Subunit : Boolean)
129 N : constant Node_Id := Info_Node;
132 -- Here we define an enumeration type to represent categorization types,
133 -- ordered so that a unit with a given categorization can only WITH
134 -- units with lower or equal categorization type.
136 type Categorization is
140 Remote_Call_Interface,
143 function Get_Categorization (E : Entity_Id) return Categorization;
144 -- Check categorization flags from entity, and return in the form
145 -- of the lowest value of the Categorization type that applies to E.
147 ------------------------
148 -- Get_Categorization --
149 ------------------------
151 function Get_Categorization (E : Entity_Id) return Categorization is
153 -- Get the lowest categorization that corresponds to E. Note that
154 -- nothing prevents several (different) categorization pragmas
155 -- to apply to the same library unit, in which case the unit has
156 -- all associated categories, so we need to be careful here to
157 -- check pragmas in proper Categorization order in order to
158 -- return the lowest applicable value.
160 -- Ignore Pure specification if set by pragma Pure_Function
164 (Has_Pragma_Pure_Function (E) and not Has_Pragma_Pure (E))
168 elsif Is_Shared_Passive (E) then
169 return Shared_Passive;
171 elsif Is_Remote_Types (E) then
174 elsif Is_Remote_Call_Interface (E) then
175 return Remote_Call_Interface;
180 end Get_Categorization;
182 Unit_Category : Categorization;
183 With_Category : Categorization;
185 -- Start of processing for Check_Categorization_Dependencies
188 -- Intrinsic subprograms are preelaborated, so do not impose any
189 -- categorization dependencies.
191 if Is_Intrinsic_Subprogram (Depended_Entity) then
195 -- First check 10.2.1 (11/1) rules on preelaborate packages
197 if Is_Preelaborated (Unit_Entity)
198 and then not Is_Preelaborated (Depended_Entity)
199 and then not Is_Pure (Depended_Entity)
206 -- Check categorization rules of RM E.2(5)
208 Unit_Category := Get_Categorization (Unit_Entity);
209 With_Category := Get_Categorization (Depended_Entity);
211 if With_Category > Unit_Category then
213 -- Special case: Remote_Types and Remote_Call_Interface are allowed
214 -- to WITH anything in the package body, per (RM E.2(5)).
216 if (Unit_Category = Remote_Types
217 or else Unit_Category = Remote_Call_Interface)
218 and then In_Package_Body (Unit_Entity)
222 -- Special case: Remote_Types and Remote_Call_Interface declarations
223 -- can depend on a preelaborated unit via a private with_clause, per
226 elsif (Unit_Category = Remote_Types
228 Unit_Category = Remote_Call_Interface)
229 and then Nkind (N) = N_With_Clause
230 and then Private_Present (N)
231 and then Is_Preelaborated (Depended_Entity)
235 -- All other cases, we do have an error
242 -- Here if we have an error
246 -- These messages are warnings in GNAT mode or if the -gnateP switch
247 -- was set. Otherwise these are real errors for real illegalities.
249 -- The reason we suppress these errors in GNAT mode is that the run-
250 -- time has several instances of violations of the categorization
251 -- errors (e.g. Pure units withing Preelaborate units. All these
252 -- violations are harmless in the cases where we intend them, and
253 -- we suppress the warnings with Warnings (Off). In cases where we
254 -- do not intend the violation, warnings are errors in GNAT mode
255 -- anyway, so we will still get an error.
258 Treat_Categorization_Errors_As_Warnings or GNAT_Mode;
260 -- Don't give error if main unit is not an internal unit, and the
261 -- unit generating the message is an internal unit. This is the
262 -- situation in which such messages would be ignored in any case,
263 -- so it is convenient not to generate them (since it causes
264 -- annoying interference with debugging).
266 if Is_Internal_File_Name (Unit_File_Name (Current_Sem_Unit))
267 and then not Is_Internal_File_Name (Unit_File_Name (Main_Unit))
271 -- Dependence of Remote_Types or Remote_Call_Interface declaration
272 -- on a preelaborated unit with a normal with_clause.
274 elsif (Unit_Category = Remote_Types
276 Unit_Category = Remote_Call_Interface)
277 and then Is_Preelaborated (Depended_Entity)
280 ("<must use private with clause for preelaborated unit& ",
285 elsif Is_Subunit then
287 ("<subunit cannot depend on& " &
288 "(parent has wrong categorization)", N, Depended_Entity);
290 -- Normal unit, not subunit
294 ("<cannot depend on& " &
295 "(wrong categorization)", N, Depended_Entity);
298 -- Add further explanation for Pure/Preelaborate common cases
300 if Unit_Category = Pure then
302 ("\<pure unit cannot depend on non-pure unit",
305 elsif Is_Preelaborated (Unit_Entity)
306 and then not Is_Preelaborated (Depended_Entity)
307 and then not Is_Pure (Depended_Entity)
310 ("\<preelaborated unit cannot depend on "
311 & "non-preelaborated unit",
315 end Check_Categorization_Dependencies;
317 -----------------------------------
318 -- Check_Non_Static_Default_Expr --
319 -----------------------------------
321 procedure Check_Non_Static_Default_Expr
326 Component_Decl : Node_Id;
329 if Nkind (Type_Def) = N_Derived_Type_Definition then
330 Recdef := Record_Extension_Part (Type_Def);
340 -- Check that component declarations do not involve:
342 -- a. a non-static default expression, where the object is
343 -- declared to be default initialized.
345 -- b. a dynamic Itype (discriminants and constraints)
347 if Null_Present (Recdef) then
350 Component_Decl := First (Component_Items (Component_List (Recdef)));
353 while Present (Component_Decl)
354 and then Nkind (Component_Decl) = N_Component_Declaration
356 if Present (Expression (Component_Decl))
357 and then Nkind (Expression (Component_Decl)) /= N_Null
358 and then not Is_Static_Expression (Expression (Component_Decl))
360 Error_Msg_Sloc := Sloc (Component_Decl);
362 ("object in preelaborated unit has non-static default#",
365 -- Fix this later ???
367 -- elsif Has_Dynamic_Itype (Component_Decl) then
369 -- ("dynamic type discriminant," &
370 -- " constraint in preelaborated unit",
374 Next (Component_Decl);
376 end Check_Non_Static_Default_Expr;
378 ---------------------------
379 -- Has_Non_Remote_Access --
380 ---------------------------
382 function Has_Non_Remote_Access (Typ : Entity_Id) return Boolean is
383 Component : Entity_Id;
384 Comp_Type : Entity_Id;
385 U_Typ : constant Entity_Id := Underlying_Type (Typ);
391 elsif Has_Read_Write_Attributes (Typ)
392 or else Has_Read_Write_Attributes (U_Typ)
396 elsif Is_Non_Remote_Access_Type (U_Typ) then
400 if Is_Record_Type (U_Typ) then
401 Component := First_Entity (U_Typ);
402 while Present (Component) loop
403 if not Is_Tag (Component) then
404 Comp_Type := Etype (Component);
406 if Has_Non_Remote_Access (Comp_Type) then
411 Next_Entity (Component);
414 elsif Is_Array_Type (U_Typ) then
415 return Has_Non_Remote_Access (Component_Type (U_Typ));
420 end Has_Non_Remote_Access;
422 -------------------------------
423 -- Has_Read_Write_Attributes --
424 -------------------------------
426 function Has_Read_Write_Attributes (E : Entity_Id) return Boolean is
429 and then Has_Stream_Attribute_Definition
430 (E, TSS_Stream_Read, At_Any_Place => True)
431 and then Has_Stream_Attribute_Definition
432 (E, TSS_Stream_Write, At_Any_Place => True);
433 end Has_Read_Write_Attributes;
435 -------------------------------------
436 -- Has_Stream_Attribute_Definition --
437 -------------------------------------
439 function Has_Stream_Attribute_Definition
442 At_Any_Place : Boolean := False) return Boolean
445 Full_Type : Entity_Id := Typ;
448 -- In the case of a type derived from a private view, any specified
449 -- stream attributes will be attached to the derived type's underlying
450 -- type rather the derived type entity itself (which is itself private).
452 if Is_Private_Type (Typ)
453 and then Is_Derived_Type (Typ)
454 and then Present (Full_View (Typ))
456 Full_Type := Underlying_Type (Typ);
459 -- We start from the declaration node and then loop until the end of
460 -- the list until we find the requested attribute definition clause.
461 -- In Ada 2005 mode, clauses are ignored if they are not currently
462 -- visible (this is tested using the corresponding Entity, which is
463 -- inserted by the expander at the point where the clause occurs),
464 -- unless At_Any_Place is true.
466 Rep_Item := First_Rep_Item (Full_Type);
467 while Present (Rep_Item) loop
468 if Nkind (Rep_Item) = N_Attribute_Definition_Clause then
469 case Chars (Rep_Item) is
471 exit when Nam = TSS_Stream_Read;
474 exit when Nam = TSS_Stream_Write;
477 exit when Nam = TSS_Stream_Input;
480 exit when Nam = TSS_Stream_Output;
488 Next_Rep_Item (Rep_Item);
491 -- If At_Any_Place is true, return True if the attribute is available
492 -- at any place; if it is false, return True only if the attribute is
493 -- currently visible.
495 return Present (Rep_Item)
496 and then (Ada_Version < Ada_2005
498 or else not Is_Hidden (Entity (Rep_Item)));
499 end Has_Stream_Attribute_Definition;
501 ---------------------------
502 -- In_Preelaborated_Unit --
503 ---------------------------
505 function In_Preelaborated_Unit return Boolean is
506 Unit_Entity : Entity_Id := Current_Scope;
507 Unit_Kind : constant Node_Kind :=
508 Nkind (Unit (Cunit (Current_Sem_Unit)));
511 -- If evaluating actuals for a child unit instantiation, then ignore
512 -- the preelaboration status of the parent; use the child instead.
514 if Is_Compilation_Unit (Unit_Entity)
515 and then Unit_Kind in N_Generic_Instantiation
516 and then not In_Same_Source_Unit (Unit_Entity,
517 Cunit (Current_Sem_Unit))
519 Unit_Entity := Cunit_Entity (Current_Sem_Unit);
522 -- There are no constraints on the body of Remote_Call_Interface or
523 -- Remote_Types packages.
525 return (Unit_Entity /= Standard_Standard)
526 and then (Is_Preelaborated (Unit_Entity)
527 or else Is_Pure (Unit_Entity)
528 or else Is_Shared_Passive (Unit_Entity)
530 ((Is_Remote_Types (Unit_Entity)
531 or else Is_Remote_Call_Interface (Unit_Entity))
532 and then Ekind (Unit_Entity) = E_Package
533 and then Unit_Kind /= N_Package_Body
534 and then not In_Package_Body (Unit_Entity)
535 and then not In_Instance));
536 end In_Preelaborated_Unit;
542 function In_Pure_Unit return Boolean is
544 return Is_Pure (Current_Scope);
547 ------------------------
548 -- In_RCI_Declaration --
549 ------------------------
551 function In_RCI_Declaration (N : Node_Id) return Boolean is
552 Unit_Entity : constant Entity_Id := Current_Scope;
553 Unit_Kind : constant Node_Kind :=
554 Nkind (Unit (Cunit (Current_Sem_Unit)));
557 -- There are no restrictions on the private part or body
560 return Is_Remote_Call_Interface (Unit_Entity)
561 and then Is_Package_Or_Generic_Package (Unit_Entity)
562 and then Unit_Kind /= N_Package_Body
563 and then List_Containing (N) =
564 Visible_Declarations (Package_Specification (Unit_Entity))
565 and then not In_Package_Body (Unit_Entity)
566 and then not In_Instance;
568 -- What about the case of a nested package in the visible part???
569 -- This case is missed by the List_Containing check above???
570 end In_RCI_Declaration;
572 -----------------------
573 -- In_RT_Declaration --
574 -----------------------
576 function In_RT_Declaration return Boolean is
577 Unit_Entity : constant Entity_Id := Current_Scope;
578 Unit_Kind : constant Node_Kind :=
579 Nkind (Unit (Cunit (Current_Sem_Unit)));
582 -- There are no restrictions on the body of a Remote Types unit
584 return Is_Remote_Types (Unit_Entity)
585 and then Is_Package_Or_Generic_Package (Unit_Entity)
586 and then Unit_Kind /= N_Package_Body
587 and then not In_Package_Body (Unit_Entity)
588 and then not In_Instance;
589 end In_RT_Declaration;
591 ----------------------------
592 -- In_Shared_Passive_Unit --
593 ----------------------------
595 function In_Shared_Passive_Unit return Boolean is
596 Unit_Entity : constant Entity_Id := Current_Scope;
599 return Is_Shared_Passive (Unit_Entity);
600 end In_Shared_Passive_Unit;
602 ---------------------------------------
603 -- In_Subprogram_Task_Protected_Unit --
604 ---------------------------------------
606 function In_Subprogram_Task_Protected_Unit return Boolean is
610 -- The following is to verify that a declaration is inside
611 -- subprogram, generic subprogram, task unit, protected unit.
612 -- Used to validate if a lib. unit is Pure. RM 10.2.1(16).
614 -- Use scope chain to check successively outer scopes
620 Is_Generic_Subprogram (E)
622 Is_Concurrent_Type (E)
626 elsif E = Standard_Standard then
632 end In_Subprogram_Task_Protected_Unit;
634 -------------------------------
635 -- Is_Non_Remote_Access_Type --
636 -------------------------------
638 function Is_Non_Remote_Access_Type (E : Entity_Id) return Boolean is
639 U_E : constant Entity_Id := Underlying_Type (E);
643 -- This case arises for the case of a generic formal type, in which
644 -- case E.2.2(8) rules will be enforced at instantiation time.
649 return Is_Access_Type (U_E)
650 and then not Is_Remote_Access_To_Class_Wide_Type (U_E)
651 and then not Is_Remote_Access_To_Subprogram_Type (U_E);
652 end Is_Non_Remote_Access_Type;
654 ---------------------------
655 -- No_External_Streaming --
656 ---------------------------
658 function No_External_Streaming (E : Entity_Id) return Boolean is
659 U_E : constant Entity_Id := Underlying_Type (E);
665 elsif Has_Read_Write_Attributes (E) then
667 -- Note: availability of stream attributes is tested on E, not U_E.
668 -- There may be stream attributes defined on U_E that are not visible
669 -- at the place where support of external streaming is tested.
673 elsif Has_Non_Remote_Access (U_E) then
677 return Is_Limited_Type (E);
678 end No_External_Streaming;
680 -------------------------------------
681 -- Set_Categorization_From_Pragmas --
682 -------------------------------------
684 procedure Set_Categorization_From_Pragmas (N : Node_Id) is
685 P : constant Node_Id := Parent (N);
686 S : constant Entity_Id := Current_Scope;
688 procedure Set_Parents (Visibility : Boolean);
689 -- If this is a child instance, the parents are not immediately
690 -- visible during analysis. Make them momentarily visible so that
691 -- the argument of the pragma can be resolved properly, and reset
698 procedure Set_Parents (Visibility : Boolean) is
702 while Present (Par) and then Par /= Standard_Standard loop
703 Set_Is_Immediately_Visible (Par, Visibility);
708 -- Start of processing for Set_Categorization_From_Pragmas
711 -- Deal with categorization pragmas in Pragmas of Compilation_Unit.
712 -- The purpose is to set categorization flags before analyzing the
713 -- unit itself, so as to diagnose violations of categorization as
714 -- we process each declaration, even though the pragma appears after
717 if Nkind (P) /= N_Compilation_Unit then
725 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then
729 PN := First (Pragmas_After (Aux_Decls_Node (P)));
730 while Present (PN) loop
732 -- Skip implicit types that may have been introduced by
733 -- previous analysis.
735 if Nkind (PN) = N_Pragma then
736 case Get_Pragma_Id (PN) is
737 when Pragma_All_Calls_Remote |
738 Pragma_Preelaborate |
740 Pragma_Remote_Call_Interface |
741 Pragma_Remote_Types |
742 Pragma_Shared_Passive => Analyze (PN);
750 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then
754 end Set_Categorization_From_Pragmas;
756 -----------------------------------
757 -- Set_Categorization_From_Scope --
758 -----------------------------------
760 procedure Set_Categorization_From_Scope (E : Entity_Id; Scop : Entity_Id) is
761 Declaration : Node_Id := Empty;
762 Specification : Node_Id := Empty;
766 (E, Is_Pure (Scop) and then Is_Library_Level_Entity (E));
768 if not Is_Remote_Call_Interface (E) then
769 if Ekind (E) in Subprogram_Kind then
770 Declaration := Unit_Declaration_Node (E);
772 if Nkind_In (Declaration, N_Subprogram_Body,
773 N_Subprogram_Renaming_Declaration)
775 Specification := Corresponding_Spec (Declaration);
779 -- A subprogram body or renaming-as-body is a remote call interface
780 -- if it serves as the completion of a subprogram declaration that
781 -- is a remote call interface.
783 if Nkind (Specification) in N_Entity then
784 Set_Is_Remote_Call_Interface
785 (E, Is_Remote_Call_Interface (Specification));
787 -- A subprogram declaration is a remote call interface when it is
788 -- declared within the visible part of, or declared by, a library
789 -- unit declaration that is a remote call interface.
792 Set_Is_Remote_Call_Interface
793 (E, Is_Remote_Call_Interface (Scop)
794 and then not (In_Private_Part (Scop)
795 or else In_Package_Body (Scop)));
800 (E, Is_Remote_Types (Scop)
801 and then not (In_Private_Part (Scop)
802 or else In_Package_Body (Scop)));
803 end Set_Categorization_From_Scope;
805 ------------------------------
806 -- Static_Discriminant_Expr --
807 ------------------------------
809 -- We need to accommodate a Why_Not_Static call somehow here ???
811 function Static_Discriminant_Expr (L : List_Id) return Boolean is
812 Discriminant_Spec : Node_Id;
815 Discriminant_Spec := First (L);
816 while Present (Discriminant_Spec) loop
817 if Present (Expression (Discriminant_Spec))
818 and then not Is_Static_Expression (Expression (Discriminant_Spec))
823 Next (Discriminant_Spec);
827 end Static_Discriminant_Expr;
829 --------------------------------------
830 -- Validate_Access_Type_Declaration --
831 --------------------------------------
833 procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id) is
834 Def : constant Node_Id := Type_Definition (N);
839 -- Access to subprogram case
841 when N_Access_To_Subprogram_Definition =>
843 -- A pure library_item must not contain the declaration of a
844 -- named access type, except within a subprogram, generic
845 -- subprogram, task unit, or protected unit (RM 10.2.1(16)).
847 -- This test is skipped in Ada 2005 (see AI-366)
849 if Ada_Version < Ada_2005
850 and then Comes_From_Source (T)
851 and then In_Pure_Unit
852 and then not In_Subprogram_Task_Protected_Unit
854 Error_Msg_N ("named access type not allowed in pure unit", T);
857 -- Access to object case
859 when N_Access_To_Object_Definition =>
860 if Comes_From_Source (T)
861 and then In_Pure_Unit
862 and then not In_Subprogram_Task_Protected_Unit
864 -- We can't give the message yet, since the type is not frozen
865 -- and in Ada 2005 mode, access types are allowed in pure units
866 -- if the type has no storage pool (see AI-366). So we set a
867 -- flag which will be checked at freeze time.
869 Set_Is_Pure_Unit_Access_Type (T);
872 -- Check for RCI or RT unit type declaration: declaration of an
873 -- access-to-object type is illegal unless it is a general access
874 -- type that designates a class-wide limited private type.
875 -- Note that constraints on the primitive subprograms of the
876 -- designated tagged type are not enforced here but in
877 -- Validate_RACW_Primitives, which is done separately because the
878 -- designated type might not be frozen (and therefore its
879 -- primitive operations might not be completely known) at the
880 -- point of the RACW declaration.
882 Validate_Remote_Access_Object_Type_Declaration (T);
884 -- Check for shared passive unit type declaration. It should
885 -- not contain the declaration of access to class wide type,
886 -- access to task type and access to protected type with entry.
888 Validate_SP_Access_Object_Type_Decl (T);
894 -- Set categorization flag from package on entity as well, to allow
895 -- easy checks later on for required validations of RCI or RT units.
896 -- This is only done for entities that are in the original source.
898 if Comes_From_Source (T)
899 and then not (In_Package_Body (Scope (T))
900 or else In_Private_Part (Scope (T)))
902 Set_Is_Remote_Call_Interface
903 (T, Is_Remote_Call_Interface (Scope (T)));
905 (T, Is_Remote_Types (Scope (T)));
907 end Validate_Access_Type_Declaration;
909 ----------------------------
910 -- Validate_Ancestor_Part --
911 ----------------------------
913 procedure Validate_Ancestor_Part (N : Node_Id) is
914 A : constant Node_Id := Ancestor_Part (N);
915 T : constant Entity_Id := Entity (A);
918 if In_Preelaborated_Unit
919 and then not In_Subprogram_Or_Concurrent_Unit
920 and then (not Inside_A_Generic
921 or else Present (Enclosing_Generic_Body (N)))
923 -- If the type is private, it must have the Ada 2005 pragma
924 -- Has_Preelaborable_Initialization.
926 -- The check is omitted within predefined units. This is probably
927 -- obsolete code to fix the Ada 95 weakness in this area ???
929 if Is_Private_Type (T)
930 and then not Has_Pragma_Preelab_Init (T)
931 and then not Is_Internal_File_Name
932 (Unit_File_Name (Get_Source_Unit (N)))
935 ("private ancestor type not allowed in preelaborated unit", A);
937 elsif Is_Record_Type (T) then
938 if Nkind (Parent (T)) = N_Full_Type_Declaration then
939 Check_Non_Static_Default_Expr
940 (Type_Definition (Parent (T)), A);
944 end Validate_Ancestor_Part;
946 ----------------------------------------
947 -- Validate_Categorization_Dependency --
948 ----------------------------------------
950 procedure Validate_Categorization_Dependency
954 K : constant Node_Kind := Nkind (N);
955 P : Node_Id := Parent (N);
957 Is_Subunit : constant Boolean := Nkind (P) = N_Subunit;
960 -- Only validate library units and subunits. For subunits, checks
961 -- concerning withed units apply to the parent compilation unit.
968 and then not Is_Compilation_Unit (U)
969 and then not Is_Child_Unit (U)
975 if Nkind (P) /= N_Compilation_Unit then
979 -- Body of RCI unit does not need validation
981 if Is_Remote_Call_Interface (E)
982 and then Nkind_In (N, N_Package_Body, N_Subprogram_Body)
987 -- Ada 2005 (AI-50217): Process explicit non-limited with_clauses
991 Entity_Of_Withed : Entity_Id;
994 Item := First (Context_Items (P));
995 while Present (Item) loop
996 if Nkind (Item) = N_With_Clause
997 and then not (Implicit_With (Item)
998 or else Limited_Present (Item)
1000 -- Skip if error already posted on the WITH
1001 -- clause (in which case the Name attribute
1002 -- may be invalid). In particular, this fixes
1003 -- the problem of hanging in the presence of a
1004 -- WITH clause on a child that is an illegal
1005 -- generic instantiation.
1007 or else Error_Posted (Item))
1009 Entity_Of_Withed := Entity (Name (Item));
1010 Check_Categorization_Dependencies
1011 (U, Entity_Of_Withed, Item, Is_Subunit);
1018 -- Child depends on parent; therefore parent should also be categorized
1019 -- and satisfy the dependency hierarchy.
1021 -- Check if N is a child spec
1023 if (K in N_Generic_Declaration or else
1024 K in N_Generic_Instantiation or else
1025 K in N_Generic_Renaming_Declaration or else
1026 K = N_Package_Declaration or else
1027 K = N_Package_Renaming_Declaration or else
1028 K = N_Subprogram_Declaration or else
1029 K = N_Subprogram_Renaming_Declaration)
1030 and then Present (Parent_Spec (N))
1032 Check_Categorization_Dependencies (E, Scope (E), N, False);
1034 -- Verify that public child of an RCI library unit must also be an
1035 -- RCI library unit (RM E.2.3(15)).
1037 if Is_Remote_Call_Interface (Scope (E))
1038 and then not Private_Present (P)
1039 and then not Is_Remote_Call_Interface (E)
1041 Error_Msg_N ("public child of rci unit must also be rci unit", N);
1044 end Validate_Categorization_Dependency;
1046 --------------------------------
1047 -- Validate_Controlled_Object --
1048 --------------------------------
1050 procedure Validate_Controlled_Object (E : Entity_Id) is
1052 -- Don't need this check in Ada 2005 mode, where this is all taken
1053 -- care of by the mechanism for Preelaborable Initialization.
1055 if Ada_Version >= Ada_2005 then
1059 -- For now, never apply this check for internal GNAT units, since we
1060 -- have a number of cases in the library where we are stuck with objects
1061 -- of this type, and the RM requires Preelaborate.
1063 -- For similar reasons, we only do this check for source entities, since
1064 -- we generate entities of this type in some situations.
1066 -- Note that the 10.2.1(9) restrictions are not relevant to us anyway.
1067 -- We have to enforce them for RM compatibility, but we have no trouble
1068 -- accepting these objects and doing the right thing. Note that there is
1069 -- no requirement that Preelaborate not actually generate any code!
1071 if In_Preelaborated_Unit
1072 and then not Debug_Flag_PP
1073 and then Comes_From_Source (E)
1075 Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (E)))
1076 and then (not Inside_A_Generic
1077 or else Present (Enclosing_Generic_Body (E)))
1078 and then not Is_Protected_Type (Etype (E))
1081 ("library level controlled object not allowed in " &
1082 "preelaborated unit", E);
1084 end Validate_Controlled_Object;
1086 --------------------------------------
1087 -- Validate_Null_Statement_Sequence --
1088 --------------------------------------
1090 procedure Validate_Null_Statement_Sequence (N : Node_Id) is
1094 if In_Preelaborated_Unit then
1095 Item := First (Statements (Handled_Statement_Sequence (N)));
1096 while Present (Item) loop
1097 if Nkind (Item) /= N_Label
1098 and then Nkind (Item) /= N_Null_Statement
1100 -- In GNAT mode, this is a warning, allowing the run-time
1101 -- to judiciously bypass this error condition.
1103 Error_Msg_Warn := GNAT_Mode;
1105 ("<statements not allowed in preelaborated unit", Item);
1113 end Validate_Null_Statement_Sequence;
1115 ---------------------------------
1116 -- Validate_Object_Declaration --
1117 ---------------------------------
1119 procedure Validate_Object_Declaration (N : Node_Id) is
1120 Id : constant Entity_Id := Defining_Identifier (N);
1121 E : constant Node_Id := Expression (N);
1122 Odf : constant Node_Id := Object_Definition (N);
1123 T : constant Entity_Id := Etype (Id);
1126 -- Verify that any access to subprogram object does not have in its
1127 -- subprogram profile access type parameters or limited parameters
1128 -- without Read and Write attributes (E.2.3(13)).
1130 Validate_RCI_Subprogram_Declaration (N);
1132 -- Check that if we are in preelaborated elaboration code, then we
1133 -- do not have an instance of a default initialized private, task or
1134 -- protected object declaration which would violate (RM 10.2.1(9)).
1135 -- Note that constants are never default initialized (and the test
1136 -- below also filters out deferred constants). A variable is default
1137 -- initialized if it does *not* have an initialization expression.
1139 -- Filter out cases that are not declaration of a variable from source
1141 if Nkind (N) /= N_Object_Declaration
1142 or else Constant_Present (N)
1143 or else not Comes_From_Source (Id)
1148 -- Exclude generic specs from the checks (this will get rechecked
1149 -- on instantiations).
1151 if Inside_A_Generic and then No (Enclosing_Generic_Body (Id)) then
1155 -- Required checks for declaration that is in a preelaborated package
1156 -- and is not within some subprogram.
1158 if In_Preelaborated_Unit
1159 and then not In_Subprogram_Or_Concurrent_Unit
1161 -- Check for default initialized variable case. Note that in
1162 -- accordance with (RM B.1(24)) imported objects are not subject to
1163 -- default initialization.
1164 -- If the initialization does not come from source and is an
1165 -- aggregate, it is a static initialization that replaces an
1166 -- implicit call, and must be treated as such.
1169 and then (Comes_From_Source (E) or else Nkind (E) /= N_Aggregate)
1173 elsif Is_Imported (Id) then
1178 Ent : Entity_Id := T;
1181 -- An array whose component type is a record with nonstatic
1182 -- default expressions is a violation, so we get the array's
1185 if Is_Array_Type (Ent) then
1187 Comp_Type : Entity_Id;
1190 Comp_Type := Component_Type (Ent);
1191 while Is_Array_Type (Comp_Type) loop
1192 Comp_Type := Component_Type (Comp_Type);
1199 -- Object decl. that is of record type and has no default expr.
1200 -- should check if there is any non-static default expression
1201 -- in component decl. of the record type decl.
1203 if Is_Record_Type (Ent) then
1204 if Nkind (Parent (Ent)) = N_Full_Type_Declaration then
1205 Check_Non_Static_Default_Expr
1206 (Type_Definition (Parent (Ent)), N);
1208 elsif Nkind (Odf) = N_Subtype_Indication
1209 and then not Is_Array_Type (T)
1210 and then not Is_Private_Type (T)
1212 Check_Non_Static_Default_Expr (Type_Definition
1213 (Parent (Entity (Subtype_Mark (Odf)))), N);
1217 -- Check for invalid use of private object. Note that Ada 2005
1218 -- AI-161 modifies the rules for Ada 2005, including the use of
1219 -- the new pragma Preelaborable_Initialization.
1221 if Is_Private_Type (Ent)
1222 or else Depends_On_Private (Ent)
1224 -- Case where type has preelaborable initialization which
1225 -- means that a pragma Preelaborable_Initialization was
1226 -- given for the private type.
1228 if Has_Preelaborable_Initialization (Ent) then
1230 -- But for the predefined units, we will ignore this
1231 -- status unless we are in Ada 2005 mode since we want
1232 -- Ada 95 compatible behavior, in which the entities
1233 -- marked with this pragma in the predefined library are
1234 -- not treated specially.
1236 if Ada_Version < Ada_2005 then
1238 ("private object not allowed in preelaborated unit",
1240 Error_Msg_N ("\(would be legal in Ada 2005 mode)", N);
1243 -- Type does not have preelaborable initialization
1246 -- We allow this when compiling in GNAT mode to make life
1247 -- easier for some cases where it would otherwise be hard
1248 -- to be exactly valid Ada.
1250 if not GNAT_Mode then
1252 ("private object not allowed in preelaborated unit",
1255 -- Add a message if it would help to provide a pragma
1256 -- Preelaborable_Initialization on the type of the
1257 -- object (which would make it legal in Ada 2005).
1259 -- If the type has no full view (generic type, or
1260 -- previous error), the warning does not apply.
1262 if Is_Private_Type (Ent)
1263 and then Present (Full_View (Ent))
1265 Has_Preelaborable_Initialization (Full_View (Ent))
1267 Error_Msg_Sloc := Sloc (Ent);
1269 if Ada_Version >= Ada_2005 then
1271 ("\would be legal if pragma Preelaborable_" &
1272 "Initialization given for & #", N, Ent);
1275 ("\would be legal in Ada 2005 if pragma " &
1276 "Preelaborable_Initialization given for & #",
1283 -- Access to Task or Protected type
1285 elsif Is_Entity_Name (Odf)
1286 and then Present (Etype (Odf))
1287 and then Is_Access_Type (Etype (Odf))
1289 Ent := Designated_Type (Etype (Odf));
1291 elsif Is_Entity_Name (Odf) then
1292 Ent := Entity (Odf);
1294 elsif Nkind (Odf) = N_Subtype_Indication then
1295 Ent := Etype (Subtype_Mark (Odf));
1297 elsif Nkind (Odf) = N_Constrained_Array_Definition then
1298 Ent := Component_Type (T);
1301 if Is_Task_Type (Ent)
1302 or else (Is_Protected_Type (Ent) and then Has_Entries (Ent))
1305 ("concurrent object not allowed in preelaborated unit",
1312 -- Non-static discriminants not allowed in preelaborated unit.
1313 -- Objects of a controlled type with a user-defined Initialize
1314 -- are forbidden as well.
1316 if Is_Record_Type (Etype (Id)) then
1318 ET : constant Entity_Id := Etype (Id);
1319 EE : constant Entity_Id := Etype (Etype (Id));
1323 if Has_Discriminants (ET) and then Present (EE) then
1326 if Nkind (PEE) = N_Full_Type_Declaration
1327 and then not Static_Discriminant_Expr
1328 (Discriminant_Specifications (PEE))
1331 ("non-static discriminant in preelaborated unit",
1336 -- For controlled type or type with controlled component, check
1337 -- preelaboration flag, as there may be a non-null Initialize
1338 -- primitive. For language versions earlier than Ada 2005,
1339 -- there is no notion of preelaborable initialization, and
1340 -- Validate_Controlled_Object is used to enforce rules for
1341 -- controlled objects.
1343 if (Is_Controlled (ET) or else Has_Controlled_Component (ET))
1344 and then Ada_Version >= Ada_2005
1345 and then not Has_Preelaborable_Initialization (ET)
1348 ("controlled type& does not have"
1349 & " preelaborable initialization", N, ET);
1356 -- A pure library_item must not contain the declaration of any variable
1357 -- except within a subprogram, generic subprogram, task unit, or
1358 -- protected unit (RM 10.2.1(16)).
1360 if In_Pure_Unit and then not In_Subprogram_Task_Protected_Unit then
1361 Error_Msg_N ("declaration of variable not allowed in pure unit", N);
1363 -- The visible part of an RCI library unit must not contain the
1364 -- declaration of a variable (RM E.1.3(9))
1366 elsif In_RCI_Declaration (N) then
1367 Error_Msg_N ("visible variable not allowed in 'R'C'I unit", N);
1369 -- The visible part of a Shared Passive library unit must not contain
1370 -- the declaration of a variable (RM E.2.2(7))
1372 elsif In_RT_Declaration and then not In_Private_Part (Id) then
1374 ("visible variable not allowed in remote types unit", N);
1377 end Validate_Object_Declaration;
1379 -----------------------------
1380 -- Validate_RACW_Primitive --
1381 -----------------------------
1383 procedure Validate_RACW_Primitive
1387 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id);
1388 -- Diagnose illegality on N. If RACW is present, report the error on it
1389 -- rather than on N.
1391 -------------------------
1392 -- Illegal_Remote_Subp --
1393 -------------------------
1395 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id) is
1397 if Present (RACW) then
1398 if not Error_Posted (RACW) then
1400 ("illegal remote access to class-wide type&", RACW);
1403 Error_Msg_Sloc := Sloc (N);
1404 Error_Msg_NE ("\\" & Msg & " in primitive& #", RACW, Subp);
1407 Error_Msg_NE (Msg & " in remote subprogram&", N, Subp);
1409 end Illegal_Remote_Subp;
1413 Param_Spec : Node_Id;
1414 Param_Type : Entity_Id;
1416 -- Start of processing for Validate_RACW_Primitive
1419 -- Check return type
1421 if Ekind (Subp) = E_Function then
1422 Rtyp := Etype (Subp);
1424 -- AI05-0101 (Binding Interpretation): The result type of a remote
1425 -- function must either support external streaming or be a
1426 -- controlling access result type.
1428 if Has_Controlling_Result (Subp) then
1431 elsif Ekind (Rtyp) = E_Anonymous_Access_Type then
1432 Illegal_Remote_Subp ("anonymous access result", Rtyp);
1434 elsif Is_Limited_Type (Rtyp) then
1435 if No (TSS (Rtyp, TSS_Stream_Read))
1437 No (TSS (Rtyp, TSS_Stream_Write))
1440 ("limited return type must have Read and Write attributes",
1442 Explain_Limited_Type (Rtyp, Parent (Subp));
1445 -- Check that the return type supports external streaming
1447 elsif No_External_Streaming (Rtyp)
1448 and then not Error_Posted (Rtyp)
1450 Illegal_Remote_Subp ("return type containing non-remote access "
1451 & "must have Read and Write attributes",
1456 Param := First_Formal (Subp);
1457 while Present (Param) loop
1459 -- Now find out if this parameter is a controlling parameter
1461 Param_Spec := Parent (Param);
1462 Param_Type := Etype (Param);
1464 if Is_Controlling_Formal (Param) then
1466 -- It is a controlling parameter, so specific checks below do not
1471 elsif Ekind_In (Param_Type, E_Anonymous_Access_Type,
1472 E_Anonymous_Access_Subprogram_Type)
1474 -- From RM E.2.2(14), no anonymous access parameter other than
1475 -- controlling ones may be used (because an anonymous access
1476 -- type never supports external streaming).
1479 ("non-controlling access parameter", Param_Spec);
1481 elsif No_External_Streaming (Param_Type)
1482 and then not Error_Posted (Param_Type)
1484 Illegal_Remote_Subp ("formal parameter in remote subprogram must "
1485 & "support external streaming", Param_Spec);
1488 -- Check next parameter in this subprogram
1490 Next_Formal (Param);
1492 end Validate_RACW_Primitive;
1494 ------------------------------
1495 -- Validate_RACW_Primitives --
1496 ------------------------------
1498 procedure Validate_RACW_Primitives (T : Entity_Id) is
1499 Desig_Type : Entity_Id;
1500 Primitive_Subprograms : Elist_Id;
1501 Subprogram_Elmt : Elmt_Id;
1502 Subprogram : Entity_Id;
1505 Desig_Type := Etype (Designated_Type (T));
1507 -- No action needed for concurrent types
1509 if Is_Concurrent_Type (Desig_Type) then
1513 Primitive_Subprograms := Primitive_Operations (Desig_Type);
1515 Subprogram_Elmt := First_Elmt (Primitive_Subprograms);
1516 while Subprogram_Elmt /= No_Elmt loop
1517 Subprogram := Node (Subprogram_Elmt);
1519 if Is_Predefined_Dispatching_Operation (Subprogram)
1520 or else Is_Hidden (Subprogram)
1522 goto Next_Subprogram;
1525 Validate_RACW_Primitive (Subp => Subprogram, RACW => T);
1528 Next_Elmt (Subprogram_Elmt);
1530 end Validate_RACW_Primitives;
1532 -------------------------------
1533 -- Validate_RCI_Declarations --
1534 -------------------------------
1536 procedure Validate_RCI_Declarations (P : Entity_Id) is
1540 E := First_Entity (P);
1541 while Present (E) loop
1542 if Comes_From_Source (E) then
1543 if Is_Limited_Type (E) then
1545 ("limited type not allowed in rci unit", Parent (E));
1546 Explain_Limited_Type (E, Parent (E));
1548 elsif Ekind_In (E, E_Generic_Function,
1550 E_Generic_Procedure)
1552 Error_Msg_N ("generic declaration not allowed in rci unit",
1555 elsif (Ekind (E) = E_Function or else Ekind (E) = E_Procedure)
1556 and then Has_Pragma_Inline (E)
1559 ("inlined subprogram not allowed in rci unit", Parent (E));
1561 -- Inner packages that are renamings need not be checked. Generic
1562 -- RCI packages are subject to the checks, but entities that come
1563 -- from formal packages are not part of the visible declarations
1564 -- of the package and are not checked.
1566 elsif Ekind (E) = E_Package then
1567 if Present (Renamed_Entity (E)) then
1570 elsif Ekind (P) /= E_Generic_Package
1571 or else List_Containing (Unit_Declaration_Node (E)) /=
1572 Generic_Formal_Declarations
1573 (Unit_Declaration_Node (P))
1575 Validate_RCI_Declarations (E);
1582 end Validate_RCI_Declarations;
1584 -----------------------------------------
1585 -- Validate_RCI_Subprogram_Declaration --
1586 -----------------------------------------
1588 procedure Validate_RCI_Subprogram_Declaration (N : Node_Id) is
1589 K : constant Node_Kind := Nkind (N);
1592 Param_Spec : Node_Id;
1593 Param_Type : Entity_Id;
1594 Error_Node : Node_Id := N;
1597 -- This procedure enforces rules on subprogram and access to subprogram
1598 -- declarations in RCI units. These rules do not apply to expander
1599 -- generated routines, which are not remote subprograms. It is called:
1601 -- 1. from Analyze_Subprogram_Declaration.
1602 -- 2. from Validate_Object_Declaration (access to subprogram).
1604 if not (Comes_From_Source (N) and then In_RCI_Declaration (N)) then
1608 if K = N_Subprogram_Declaration then
1609 Id := Defining_Unit_Name (Specification (N));
1610 Profile := Parameter_Specifications (Specification (N));
1612 else pragma Assert (K = N_Object_Declaration);
1614 -- The above assertion is dubious, the visible declarations of an
1615 -- RCI unit never contain an object declaration, this should be an
1616 -- ACCESS-to-object declaration???
1618 Id := Defining_Identifier (N);
1620 if Nkind (Id) = N_Defining_Identifier
1621 and then Nkind (Parent (Etype (Id))) = N_Full_Type_Declaration
1622 and then Ekind (Etype (Id)) = E_Access_Subprogram_Type
1625 Parameter_Specifications (Type_Definition (Parent (Etype (Id))));
1631 -- Iterate through the parameter specification list, checking that
1632 -- no access parameter and no limited type parameter in the list.
1635 if Present (Profile) then
1636 Param_Spec := First (Profile);
1637 while Present (Param_Spec) loop
1638 Param_Type := Etype (Defining_Identifier (Param_Spec));
1640 if Ekind (Param_Type) = E_Anonymous_Access_Type then
1641 if K = N_Subprogram_Declaration then
1642 Error_Node := Param_Spec;
1645 -- Report error only if declaration is in source program
1647 if Comes_From_Source
1648 (Defining_Entity (Specification (N)))
1651 ("subprogram in 'R'C'I unit cannot have access parameter",
1655 -- For a limited private type parameter, we check only the private
1656 -- declaration and ignore full type declaration, unless this is
1657 -- the only declaration for the type, e.g., as a limited record.
1659 elsif No_External_Streaming (Param_Type) then
1660 if K = N_Subprogram_Declaration then
1661 Error_Node := Param_Spec;
1665 ("formal of remote subprogram& "
1666 & "must support external streaming",
1668 if Is_Limited_Type (Param_Type) then
1669 Explain_Limited_Type (Param_Type, Error_Node);
1676 -- No check on return type???
1678 end Validate_RCI_Subprogram_Declaration;
1680 ----------------------------------------------------
1681 -- Validate_Remote_Access_Object_Type_Declaration --
1682 ----------------------------------------------------
1684 procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id) is
1685 Direct_Designated_Type : Entity_Id;
1686 Desig_Type : Entity_Id;
1689 -- We are called from Analyze_Full_Type_Declaration, and the Nkind of
1690 -- the given node is N_Access_To_Object_Definition.
1692 if not Comes_From_Source (T)
1693 or else (not In_RCI_Declaration (Parent (T))
1694 and then not In_RT_Declaration)
1699 -- An access definition in the private part of a Remote Types package
1700 -- may be legal if it has user-defined Read and Write attributes. This
1701 -- will be checked at the end of the package spec processing.
1703 if In_RT_Declaration and then In_Private_Part (Scope (T)) then
1707 -- Check RCI or RT unit type declaration. It may not contain the
1708 -- declaration of an access-to-object type unless it is a general access
1709 -- type that designates a class-wide limited private type or subtype.
1710 -- There are also constraints on the primitive subprograms of the
1711 -- class-wide type (RM E.2.2(14), see Validate_RACW_Primitives).
1713 if Ekind (T) /= E_General_Access_Type
1714 or else not Is_Class_Wide_Type (Designated_Type (T))
1716 if In_RCI_Declaration (Parent (T)) then
1718 ("error in access type in Remote_Call_Interface unit", T);
1721 ("error in access type in Remote_Types unit", T);
1724 Error_Msg_N ("\must be general access to class-wide type", T);
1728 Direct_Designated_Type := Designated_Type (T);
1729 Desig_Type := Etype (Direct_Designated_Type);
1731 -- Why is this check not in Validate_Remote_Access_To_Class_Wide_Type???
1733 if not Is_Valid_Remote_Object_Type (Desig_Type) then
1735 ("error in designated type of remote access to class-wide type", T);
1737 ("\must be tagged limited private or private extension", T);
1740 end Validate_Remote_Access_Object_Type_Declaration;
1742 -----------------------------------------------
1743 -- Validate_Remote_Access_To_Class_Wide_Type --
1744 -----------------------------------------------
1746 procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id) is
1747 K : constant Node_Kind := Nkind (N);
1748 PK : constant Node_Kind := Nkind (Parent (N));
1752 -- This subprogram enforces the checks in (RM E.2.2(8)) for certain uses
1753 -- of class-wide limited private types.
1755 -- Storage_Pool and Storage_Size are not defined for such types
1757 -- The expected type of allocator must not be such a type.
1759 -- The actual parameter of generic instantiation must not be such a
1760 -- type if the formal parameter is of an access type.
1762 -- On entry, there are several cases:
1764 -- 1. called from sem_attr Analyze_Attribute where attribute name is
1765 -- either Storage_Pool or Storage_Size.
1767 -- 2. called from exp_ch4 Expand_N_Allocator
1769 -- 3. called from sem_ch4 Analyze_Explicit_Dereference
1771 -- 4. called from sem_res Resolve_Actuals
1773 if K = N_Attribute_Reference then
1774 E := Etype (Prefix (N));
1776 if Is_Remote_Access_To_Class_Wide_Type (E) then
1777 Error_Msg_N ("incorrect attribute of remote operand", N);
1781 elsif K = N_Allocator then
1784 if Is_Remote_Access_To_Class_Wide_Type (E) then
1785 Error_Msg_N ("incorrect expected remote type of allocator", N);
1789 -- This subprogram also enforces the checks in E.2.2(13). A value of
1790 -- such type must not be dereferenced unless as controlling operand of
1791 -- a dispatching call. Explicit dereferences not coming from source are
1792 -- exempted from this checking because the expander produces them in
1793 -- some cases (such as for tag checks on dispatching calls with multiple
1794 -- controlling operands). However we do check in the case of an implicit
1795 -- dereference that is expanded to an explicit dereference (hence the
1796 -- test of whether Original_Node (N) comes from source).
1798 elsif K = N_Explicit_Dereference
1799 and then Comes_From_Source (Original_Node (N))
1801 E := Etype (Prefix (N));
1803 -- If the class-wide type is not a remote one, the restrictions
1806 if not Is_Remote_Access_To_Class_Wide_Type (E) then
1810 -- If we have a true dereference that comes from source and that
1811 -- is a controlling argument for a dispatching call, accept it.
1813 if Is_Actual_Parameter (N) and then Is_Controlling_Actual (N) then
1817 -- If we are just within a procedure or function call and the
1818 -- dereference has not been analyzed, return because this procedure
1819 -- will be called again from sem_res Resolve_Actuals. The same can
1820 -- apply in the case of dereference that is the prefix of a selected
1821 -- component, which can be a call given in prefixed form.
1823 if (Is_Actual_Parameter (N) or else PK = N_Selected_Component)
1824 and then not Analyzed (N)
1829 -- We must allow expanded code to generate a reference to the tag of
1830 -- the designated object (may be either the actual tag, or the stub
1831 -- tag in the case of a remote object).
1833 if PK = N_Selected_Component
1834 and then Is_Tag (Entity (Selector_Name (Parent (N))))
1840 ("invalid dereference of a remote access-to-class-wide value", N);
1842 end Validate_Remote_Access_To_Class_Wide_Type;
1844 ------------------------------------------
1845 -- Validate_Remote_Type_Type_Conversion --
1846 ------------------------------------------
1848 procedure Validate_Remote_Type_Type_Conversion (N : Node_Id) is
1849 S : constant Entity_Id := Etype (N);
1850 E : constant Entity_Id := Etype (Expression (N));
1853 -- This test is required in the case where a conversion appears inside a
1854 -- normal package, it does not necessarily have to be inside an RCI,
1855 -- Remote_Types unit (RM E.2.2(9,12)).
1857 if Is_Remote_Access_To_Subprogram_Type (E)
1858 and then not Is_Remote_Access_To_Subprogram_Type (S)
1861 ("incorrect conversion of remote operand to local type", N);
1864 elsif not Is_Remote_Access_To_Subprogram_Type (E)
1865 and then Is_Remote_Access_To_Subprogram_Type (S)
1868 ("incorrect conversion of local operand to remote type", N);
1871 elsif Is_Remote_Access_To_Class_Wide_Type (E)
1872 and then not Is_Remote_Access_To_Class_Wide_Type (S)
1875 ("incorrect conversion of remote operand to local type", N);
1879 -- If a local access type is converted into a RACW type, then the
1880 -- current unit has a pointer that may now be exported to another
1883 if Is_Remote_Access_To_Class_Wide_Type (S)
1884 and then not Is_Remote_Access_To_Class_Wide_Type (E)
1886 Set_Has_RACW (Current_Sem_Unit);
1888 end Validate_Remote_Type_Type_Conversion;
1890 -------------------------------
1891 -- Validate_RT_RAT_Component --
1892 -------------------------------
1894 procedure Validate_RT_RAT_Component (N : Node_Id) is
1895 Spec : constant Node_Id := Specification (N);
1896 Name_U : constant Entity_Id := Defining_Entity (Spec);
1899 First_Priv_Ent : constant Entity_Id := First_Private_Entity (Name_U);
1901 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean;
1902 -- True if any stream attribute is available for Typ
1904 ---------------------------------
1905 -- Stream_Attributes_Available --
1906 ---------------------------------
1908 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean
1911 return Stream_Attribute_Available (Typ, TSS_Stream_Read)
1913 Stream_Attribute_Available (Typ, TSS_Stream_Write)
1915 Stream_Attribute_Available (Typ, TSS_Stream_Input)
1917 Stream_Attribute_Available (Typ, TSS_Stream_Output);
1918 end Stream_Attributes_Available;
1920 -- Start of processing for Validate_RT_RAT_Component
1923 if not Is_Remote_Types (Name_U) then
1927 Typ := First_Entity (Name_U);
1928 while Present (Typ) and then Typ /= First_Priv_Ent loop
1929 U_Typ := Underlying_Type (Typ);
1935 if Comes_From_Source (Typ) and then Is_Type (Typ) then
1937 -- Check that the type can be meaningfully transmitted to another
1938 -- partition (E.2.2(8)).
1940 if (Ada_Version < Ada_2005 and then Has_Non_Remote_Access (U_Typ))
1941 or else (Stream_Attributes_Available (Typ)
1942 and then No_External_Streaming (U_Typ))
1944 if Is_Non_Remote_Access_Type (Typ) then
1945 Error_Msg_N ("error in non-remote access type", U_Typ);
1948 ("error in record type containing a component of a " &
1949 "non-remote access type", U_Typ);
1952 if Ada_Version >= Ada_2005 then
1954 ("\must have visible Read and Write attribute " &
1955 "definition clauses (RM E.2.2(8))", U_Typ);
1958 ("\must have Read and Write attribute " &
1959 "definition clauses (RM E.2.2(8))", U_Typ);
1966 end Validate_RT_RAT_Component;
1968 -----------------------------------------
1969 -- Validate_SP_Access_Object_Type_Decl --
1970 -----------------------------------------
1972 procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id) is
1973 Direct_Designated_Type : Entity_Id;
1975 function Has_Entry_Declarations (E : Entity_Id) return Boolean;
1976 -- Return true if the protected type designated by T has entry
1979 ----------------------------
1980 -- Has_Entry_Declarations --
1981 ----------------------------
1983 function Has_Entry_Declarations (E : Entity_Id) return Boolean is
1987 if Nkind (Parent (E)) = N_Protected_Type_Declaration then
1988 Ety := First_Entity (E);
1989 while Present (Ety) loop
1990 if Ekind (Ety) = E_Entry then
1999 end Has_Entry_Declarations;
2001 -- Start of processing for Validate_SP_Access_Object_Type_Decl
2004 -- We are called from Sem_Ch3.Analyze_Full_Type_Declaration, and the
2005 -- Nkind of the given entity is N_Access_To_Object_Definition.
2007 if not Comes_From_Source (T)
2008 or else not In_Shared_Passive_Unit
2009 or else In_Subprogram_Task_Protected_Unit
2014 -- Check Shared Passive unit. It should not contain the declaration
2015 -- of an access-to-object type whose designated type is a class-wide
2016 -- type, task type or protected type with entry (RM E.2.1(7)).
2018 Direct_Designated_Type := Designated_Type (T);
2020 if Ekind (Direct_Designated_Type) = E_Class_Wide_Type then
2022 ("invalid access-to-class-wide type in shared passive unit", T);
2025 elsif Ekind (Direct_Designated_Type) in Task_Kind then
2027 ("invalid access-to-task type in shared passive unit", T);
2030 elsif Ekind (Direct_Designated_Type) in Protected_Kind
2031 and then Has_Entry_Declarations (Direct_Designated_Type)
2034 ("invalid access-to-protected type in shared passive unit", T);
2037 end Validate_SP_Access_Object_Type_Decl;
2039 ---------------------------------
2040 -- Validate_Static_Object_Name --
2041 ---------------------------------
2043 procedure Validate_Static_Object_Name (N : Node_Id) is
2046 function Is_Primary (N : Node_Id) return Boolean;
2047 -- Determine whether node is syntactically a primary in an expression
2048 -- This function should probably be somewhere else ???
2050 -- Also it does not do what it says, e.g if N is a binary operator
2051 -- whose parent is a binary operator, Is_Primary returns True ???
2057 function Is_Primary (N : Node_Id) return Boolean is
2058 K : constant Node_Kind := Nkind (Parent (N));
2062 when N_Op | N_Membership_Test =>
2066 | N_Component_Association
2067 | N_Index_Or_Discriminant_Constraint =>
2070 when N_Attribute_Reference =>
2071 return Attribute_Name (Parent (N)) /= Name_Address
2072 and then Attribute_Name (Parent (N)) /= Name_Access
2073 and then Attribute_Name (Parent (N)) /= Name_Unchecked_Access
2075 Attribute_Name (Parent (N)) /= Name_Unrestricted_Access;
2077 when N_Indexed_Component =>
2078 return (N /= Prefix (Parent (N))
2079 or else Is_Primary (Parent (N)));
2081 when N_Qualified_Expression | N_Type_Conversion =>
2082 return Is_Primary (Parent (N));
2084 when N_Assignment_Statement | N_Object_Declaration =>
2085 return (N = Expression (Parent (N)));
2087 when N_Selected_Component =>
2088 return Is_Primary (Parent (N));
2095 -- Start of processing for Validate_Static_Object_Name
2098 if not In_Preelaborated_Unit
2099 or else not Comes_From_Source (N)
2100 or else In_Subprogram_Or_Concurrent_Unit
2101 or else Ekind (Current_Scope) = E_Block
2105 -- Filter out cases where primary is default in a component declaration,
2106 -- discriminant specification, or actual in a record type initialization
2109 -- Initialization call of internal types
2111 elsif Nkind (Parent (N)) = N_Procedure_Call_Statement then
2113 if Present (Parent (Parent (N)))
2114 and then Nkind (Parent (Parent (N))) = N_Freeze_Entity
2119 if Nkind (Name (Parent (N))) = N_Identifier
2120 and then not Comes_From_Source (Entity (Name (Parent (N))))
2126 -- Error if the name is a primary in an expression. The parent must not
2127 -- be an operator, or a selected component or an indexed component that
2128 -- is itself a primary. Entities that are actuals do not need to be
2129 -- checked, because the call itself will be diagnosed.
2132 and then (not Inside_A_Generic
2133 or else Present (Enclosing_Generic_Body (N)))
2135 if Ekind (Entity (N)) = E_Variable
2136 or else Ekind (Entity (N)) in Formal_Object_Kind
2138 Flag_Non_Static_Expr
2139 ("non-static object name in preelaborated unit", N);
2141 -- Give an error for a reference to a nonstatic constant, unless the
2142 -- constant is in another GNAT library unit that is preelaborable.
2144 elsif Ekind (Entity (N)) = E_Constant
2145 and then not Is_Static_Expression (N)
2149 if Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2151 Enclosing_Comp_Unit_Node (N) /= Enclosing_Comp_Unit_Node (E)
2152 and then (Is_Preelaborated (Scope (E))
2153 or else Is_Pure (Scope (E))
2154 or else (Present (Renamed_Object (E))
2155 and then Is_Entity_Name (Renamed_Object (E))
2158 (Scope (Renamed_Object (E)))
2161 (Renamed_Object (E))))))
2165 -- This is the error case
2168 -- In GNAT mode, this is just a warning, to allow it to be
2169 -- judiciously turned off. Otherwise it is a real error.
2173 ("??non-static constant in preelaborated unit", N);
2175 Flag_Non_Static_Expr
2176 ("non-static constant in preelaborated unit", N);
2181 end Validate_Static_Object_Name;